1/*
2 * This file is derived from various .h and .c files from the zlib-1.0.4
3 * distribution by Jean-loup Gailly and Mark Adler, with some additions
4 * by Paul Mackerras to aid in implementing Deflate compression and
5 * decompression for PPP packets. See zlib.h for conditions of
6 * distribution and use.
7 *
8 * Changes that have been made include:
9 * - added Z_PACKET_FLUSH (see zlib.h for details)
10 * - added inflateIncomp and deflateOutputPending
11 * - allow strm->next_out to be NULL, meaning discard the output
12 *
13 * $Id: zlib.c,v 1.6 1998/03/21 20:56:15 peter Exp $
14 */
15
16/*
17 * ==FILEVERSION 971210==
18 *
19 * This marker is used by the Linux installation script to determine
20 * whether an up-to-date version of this file is already installed.
21 */
22
23#define NO_DUMMY_DECL
24#define NO_ZCFUNCS
25#define MY_ZCALLOC
26
27#if defined(__FreeBSD__) && (defined(KERNEL) || defined(_KERNEL))
28#define inflate inflate_ppp /* FreeBSD already has an inflate :-( */
29#endif
30
31
32/* +++ zutil.h */
33/* zutil.h -- internal interface and configuration of the compression library
34 * Copyright (C) 1995-1996 Jean-loup Gailly.
35 * For conditions of distribution and use, see copyright notice in zlib.h
36 */
37
38/* WARNING: this file should *not* be used by applications. It is
39 part of the implementation of the compression library and is
40 subject to change. Applications should only use zlib.h.
41 */
42
43/* From: zutil.h,v 1.16 1996/07/24 13:41:13 me Exp $ */
44
45#ifndef _Z_UTIL_H
46#define _Z_UTIL_H
47
48#ifdef KERNEL
49#include <net/zlib.h>
50#else
51#include "zlib.h"
52#endif
53
54#if defined(KERNEL) || defined(_KERNEL)
55/* Assume this is a *BSD or SVR4 kernel */
56#include <sys/types.h>
57#include <sys/time.h>
58#include <sys/systm.h>
59# define HAVE_MEMCPY
60# define memcpy(d, s, n) bcopy((s), (d), (n))
61# define memset(d, v, n) bzero((d), (n))
62# define memcmp bcmp
63
64#else
65#if defined(__KERNEL__)
66/* Assume this is a Linux kernel */
67#include <linux/string.h>
68#define HAVE_MEMCPY
69
70#else /* not kernel */
71
72#if defined(MSDOS)||defined(VMS)||defined(CRAY)||defined(WIN32)||defined(RISCOS)
73# include <stddef.h>
74# include <errno.h>
75#else
76 extern int errno;
77#endif
78#ifdef STDC
79# include <string.h>
80# include <stdlib.h>
81#endif
82#endif /* __KERNEL__ */
83#endif /* _KERNEL || KERNEL */
84
85#ifndef local
86# define local static
87#endif
88/* compile with -Dlocal if your debugger can't find static symbols */
89
90typedef unsigned char uch;
91typedef uch FAR uchf;
92typedef unsigned short ush;
93typedef ush FAR ushf;
94typedef unsigned long ulg;
95
96extern const char *z_errmsg[10]; /* indexed by 2-zlib_error */
97/* (size given to avoid silly warnings with Visual C++) */
98
99#define ERR_MSG(err) z_errmsg[Z_NEED_DICT-(err)]
100
101#define ERR_RETURN(strm,err) \
102 return (strm->msg = (char*)ERR_MSG(err), (err))
103/* To be used only when the state is known to be valid */
104
105 /* common constants */
106
107#ifndef DEF_WBITS
108# define DEF_WBITS MAX_WBITS
109#endif
110/* default windowBits for decompression. MAX_WBITS is for compression only */
111
112#if MAX_MEM_LEVEL >= 8
113# define DEF_MEM_LEVEL 8
114#else
115# define DEF_MEM_LEVEL MAX_MEM_LEVEL
116#endif
117/* default memLevel */
118
119#define STORED_BLOCK 0
120#define STATIC_TREES 1
121#define DYN_TREES 2
122/* The three kinds of block type */
123
124#define MIN_MATCH 3
125#define MAX_MATCH 258
126/* The minimum and maximum match lengths */
127
128#define PRESET_DICT 0x20 /* preset dictionary flag in zlib header */
129
130 /* target dependencies */
131
132#ifdef MSDOS
133# define OS_CODE 0x00
134# ifdef __TURBOC__
135# include <alloc.h>
136# else /* MSC or DJGPP */
137# include <malloc.h>
138# endif
139#endif
140
141#ifdef OS2
142# define OS_CODE 0x06
143#endif
144
145#ifdef WIN32 /* Window 95 & Windows NT */
146# define OS_CODE 0x0b
147#endif
148
149#if defined(VAXC) || defined(VMS)
150# define OS_CODE 0x02
151# define FOPEN(name, mode) \
152 fopen((name), (mode), "mbc=60", "ctx=stm", "rfm=fix", "mrs=512")
153#endif
154
155#ifdef AMIGA
156# define OS_CODE 0x01
157#endif
158
159#if defined(ATARI) || defined(atarist)
160# define OS_CODE 0x05
161#endif
162
163#ifdef MACOS
164# define OS_CODE 0x07
165#endif
166
167#ifdef __50SERIES /* Prime/PRIMOS */
168# define OS_CODE 0x0F
169#endif
170
171#ifdef TOPS20
172# define OS_CODE 0x0a
173#endif
174
175#if defined(_BEOS_) || defined(RISCOS)
176# define fdopen(fd,mode) NULL /* No fdopen() */
177#endif
178
179 /* Common defaults */
180
181#ifndef OS_CODE
182# define OS_CODE 0x03 /* assume Unix */
183#endif
184
185#ifndef FOPEN
186# define FOPEN(name, mode) fopen((name), (mode))
187#endif
188
189 /* functions */
190
191#ifdef HAVE_STRERROR
192 extern char *strerror OF((int));
193# define zstrerror(errnum) strerror(errnum)
194#else
195# define zstrerror(errnum) ""
196#endif
197
198#if defined(pyr)
199# define NO_MEMCPY
200#endif
201#if (defined(M_I86SM) || defined(M_I86MM)) && !defined(_MSC_VER)
202 /* Use our own functions for small and medium model with MSC <= 5.0.
203 * You may have to use the same strategy for Borland C (untested).
204 */
205# define NO_MEMCPY
206#endif
207#if defined(STDC) && !defined(HAVE_MEMCPY) && !defined(NO_MEMCPY)
208# define HAVE_MEMCPY
209#endif
210#ifdef HAVE_MEMCPY
211# ifdef SMALL_MEDIUM /* MSDOS small or medium model */
212# define zmemcpy _fmemcpy
213# define zmemcmp _fmemcmp
214# define zmemzero(dest, len) _fmemset(dest, 0, len)
215# else
216# define zmemcpy memcpy
217# define zmemcmp memcmp
218# define zmemzero(dest, len) memset(dest, 0, len)
219# endif
220#else
221 extern void zmemcpy OF((Bytef* dest, Bytef* source, uInt len));
222 extern int zmemcmp OF((Bytef* s1, Bytef* s2, uInt len));
223 extern void zmemzero OF((Bytef* dest, uInt len));
224#endif
225
226/* Diagnostic functions */
227#ifdef DEBUG_ZLIB
228# include <stdio.h>
229# ifndef verbose
230# define verbose 0
231# endif
232 extern void z_error OF((char *m));
233# define Assert(cond,msg) {if(!(cond)) z_error(msg);}
234# define Trace(x) fprintf x
235# define Tracev(x) {if (verbose) fprintf x ;}
236# define Tracevv(x) {if (verbose>1) fprintf x ;}
237# define Tracec(c,x) {if (verbose && (c)) fprintf x ;}
238# define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;}
239#else
240# define Assert(cond,msg)
241# define Trace(x)
242# define Tracev(x)
243# define Tracevv(x)
244# define Tracec(c,x)
245# define Tracecv(c,x)
246#endif
247
248
249typedef uLong (*check_func) OF((uLong check, const Bytef *buf, uInt len));
250
251voidpf zcalloc OF((voidpf opaque, unsigned items, unsigned size));
252void zcfree OF((voidpf opaque, voidpf ptr));
253
254#define ZALLOC(strm, items, size) \
255 (*((strm)->zalloc))((strm)->opaque, (items), (size))
256#define ZFREE(strm, addr) (*((strm)->zfree))((strm)->opaque, (voidpf)(addr))
257#define TRY_FREE(s, p) {if (p) ZFREE(s, p);}
258
259#endif /* _Z_UTIL_H */
260/* --- zutil.h */
261
262/* +++ deflate.h */
263/* deflate.h -- internal compression state
264 * Copyright (C) 1995-1996 Jean-loup Gailly
265 * For conditions of distribution and use, see copyright notice in zlib.h
266 */
267
268/* WARNING: this file should *not* be used by applications. It is
269 part of the implementation of the compression library and is
270 subject to change. Applications should only use zlib.h.
271 */
272
273/* From: deflate.h,v 1.10 1996/07/02 12:41:00 me Exp $ */
274
275#ifndef _DEFLATE_H
276#define _DEFLATE_H
277
278/* #include "zutil.h" */
279
280/* ===========================================================================
281 * Internal compression state.
282 */
283
284#define LENGTH_CODES 29
285/* number of length codes, not counting the special END_BLOCK code */
286
287#define LITERALS 256
288/* number of literal bytes 0..255 */
289
290#define L_CODES (LITERALS+1+LENGTH_CODES)
291/* number of Literal or Length codes, including the END_BLOCK code */
292
293#define D_CODES 30
294/* number of distance codes */
295
296#define BL_CODES 19
297/* number of codes used to transfer the bit lengths */
298
299#define HEAP_SIZE (2*L_CODES+1)
300/* maximum heap size */
301
302#define MAX_BITS 15
303/* All codes must not exceed MAX_BITS bits */
304
305#define INIT_STATE 42
306#define BUSY_STATE 113
307#define FINISH_STATE 666
308/* Stream status */
309
310
311/* Data structure describing a single value and its code string. */
312typedef struct ct_data_s {
313 union {
314 ush freq; /* frequency count */
315 ush code; /* bit string */
316 } fc;
317 union {
318 ush dad; /* father node in Huffman tree */
319 ush len; /* length of bit string */
320 } dl;
321} FAR ct_data;
322
323#define Freq fc.freq
324#define Code fc.code
325#define Dad dl.dad
326#define Len dl.len
327
328typedef struct static_tree_desc_s static_tree_desc;
329
330typedef struct tree_desc_s {
331 ct_data *dyn_tree; /* the dynamic tree */
332 int max_code; /* largest code with non zero frequency */
333 static_tree_desc *stat_desc; /* the corresponding static tree */
334} FAR tree_desc;
335
336typedef ush Pos;
337typedef Pos FAR Posf;
338typedef unsigned IPos;
339
340/* A Pos is an index in the character window. We use short instead of int to
341 * save space in the various tables. IPos is used only for parameter passing.
342 */
343
344typedef struct deflate_state {
345 z_streamp strm; /* pointer back to this zlib stream */
346 int status; /* as the name implies */
347 Bytef *pending_buf; /* output still pending */
348 ulg pending_buf_size; /* size of pending_buf */
349 Bytef *pending_out; /* next pending byte to output to the stream */
350 int pending; /* nb of bytes in the pending buffer */
351 int noheader; /* suppress zlib header and adler32 */
352 Byte data_type; /* UNKNOWN, BINARY or ASCII */
353 Byte method; /* STORED (for zip only) or DEFLATED */
354 int last_flush; /* value of flush param for previous deflate call */
355
356 /* used by deflate.c: */
357
358 uInt w_size; /* LZ77 window size (32K by default) */
359 uInt w_bits; /* log2(w_size) (8..16) */
360 uInt w_mask; /* w_size - 1 */
361
362 Bytef *window;
363 /* Sliding window. Input bytes are read into the second half of the window,
364 * and move to the first half later to keep a dictionary of at least wSize
365 * bytes. With this organization, matches are limited to a distance of
366 * wSize-MAX_MATCH bytes, but this ensures that IO is always
367 * performed with a length multiple of the block size. Also, it limits
368 * the window size to 64K, which is quite useful on MSDOS.
369 * To do: use the user input buffer as sliding window.
370 */
371
372 ulg window_size;
373 /* Actual size of window: 2*wSize, except when the user input buffer
374 * is directly used as sliding window.
375 */
376
377 Posf *prev;
378 /* Link to older string with same hash index. To limit the size of this
379 * array to 64K, this link is maintained only for the last 32K strings.
380 * An index in this array is thus a window index modulo 32K.
381 */
382
383 Posf *head; /* Heads of the hash chains or NIL. */
384
385 uInt ins_h; /* hash index of string to be inserted */
386 uInt hash_size; /* number of elements in hash table */
387 uInt hash_bits; /* log2(hash_size) */
388 uInt hash_mask; /* hash_size-1 */
389
390 uInt hash_shift;
391 /* Number of bits by which ins_h must be shifted at each input
392 * step. It must be such that after MIN_MATCH steps, the oldest
393 * byte no longer takes part in the hash key, that is:
394 * hash_shift * MIN_MATCH >= hash_bits
395 */
396
397 long block_start;
398 /* Window position at the beginning of the current output block. Gets
399 * negative when the window is moved backwards.
400 */
401
402 uInt match_length; /* length of best match */
403 IPos prev_match; /* previous match */
404 int match_available; /* set if previous match exists */
405 uInt strstart; /* start of string to insert */
406 uInt match_start; /* start of matching string */
407 uInt lookahead; /* number of valid bytes ahead in window */
408
409 uInt prev_length;
410 /* Length of the best match at previous step. Matches not greater than this
411 * are discarded. This is used in the lazy match evaluation.
412 */
413
414 uInt max_chain_length;
415 /* To speed up deflation, hash chains are never searched beyond this
416 * length. A higher limit improves compression ratio but degrades the
417 * speed.
418 */
419
420 uInt max_lazy_match;
421 /* Attempt to find a better match only when the current match is strictly
422 * smaller than this value. This mechanism is used only for compression
423 * levels >= 4.
424 */
425# define max_insert_length max_lazy_match
426 /* Insert new strings in the hash table only if the match length is not
427 * greater than this length. This saves time but degrades compression.
428 * max_insert_length is used only for compression levels <= 3.
429 */
430
431 int level; /* compression level (1..9) */
432 int strategy; /* favor or force Huffman coding*/
433
434 uInt good_match;
435 /* Use a faster search when the previous match is longer than this */
436
437 int nice_match; /* Stop searching when current match exceeds this */
438
439 /* used by trees.c: */
440 /* Didn't use ct_data typedef below to supress compiler warning */
441 struct ct_data_s dyn_ltree[HEAP_SIZE]; /* literal and length tree */
442 struct ct_data_s dyn_dtree[2*D_CODES+1]; /* distance tree */
443 struct ct_data_s bl_tree[2*BL_CODES+1]; /* Huffman tree for bit lengths */
444
445 struct tree_desc_s l_desc; /* desc. for literal tree */
446 struct tree_desc_s d_desc; /* desc. for distance tree */
447 struct tree_desc_s bl_desc; /* desc. for bit length tree */
448
449 ush bl_count[MAX_BITS+1];
450 /* number of codes at each bit length for an optimal tree */
451
452 int heap[2*L_CODES+1]; /* heap used to build the Huffman trees */
453 int heap_len; /* number of elements in the heap */
454 int heap_max; /* element of largest frequency */
455 /* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used.
456 * The same heap array is used to build all trees.
457 */
458
459 uch depth[2*L_CODES+1];
460 /* Depth of each subtree used as tie breaker for trees of equal frequency
461 */
462
463 uchf *l_buf; /* buffer for literals or lengths */
464
465 uInt lit_bufsize;
466 /* Size of match buffer for literals/lengths. There are 4 reasons for
467 * limiting lit_bufsize to 64K:
468 * - frequencies can be kept in 16 bit counters
469 * - if compression is not successful for the first block, all input
470 * data is still in the window so we can still emit a stored block even
471 * when input comes from standard input. (This can also be done for
472 * all blocks if lit_bufsize is not greater than 32K.)
473 * - if compression is not successful for a file smaller than 64K, we can
474 * even emit a stored file instead of a stored block (saving 5 bytes).
475 * This is applicable only for zip (not gzip or zlib).
476 * - creating new Huffman trees less frequently may not provide fast
477 * adaptation to changes in the input data statistics. (Take for
478 * example a binary file with poorly compressible code followed by
479 * a highly compressible string table.) Smaller buffer sizes give
480 * fast adaptation but have of course the overhead of transmitting
481 * trees more frequently.
482 * - I can't count above 4
483 */
484
485 uInt last_lit; /* running index in l_buf */
486
487 ushf *d_buf;
488 /* Buffer for distances. To simplify the code, d_buf and l_buf have
489 * the same number of elements. To use different lengths, an extra flag
490 * array would be necessary.
491 */
492
493 ulg opt_len; /* bit length of current block with optimal trees */
494 ulg static_len; /* bit length of current block with static trees */
495 ulg compressed_len; /* total bit length of compressed file */
496 uInt matches; /* number of string matches in current block */
497 int last_eob_len; /* bit length of EOB code for last block */
498
499#ifdef DEBUG_ZLIB
500 ulg bits_sent; /* bit length of the compressed data */
501#endif
502
503 ush bi_buf;
504 /* Output buffer. bits are inserted starting at the bottom (least
505 * significant bits).
506 */
507 int bi_valid;
508 /* Number of valid bits in bi_buf. All bits above the last valid bit
509 * are always zero.
510 */
511
512} FAR deflate_state;
513
514/* Output a byte on the stream.
515 * IN assertion: there is enough room in pending_buf.
516 */
517#define put_byte(s, c) {s->pending_buf[s->pending++] = (c);}
518
519
520#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
521/* Minimum amount of lookahead, except at the end of the input file.
522 * See deflate.c for comments about the MIN_MATCH+1.
523 */
524
525#define MAX_DIST(s) ((s)->w_size-MIN_LOOKAHEAD)
526/* In order to simplify the code, particularly on 16 bit machines, match
527 * distances are limited to MAX_DIST instead of WSIZE.
528 */
529
530 /* in trees.c */
531void _tr_init OF((deflate_state *s));
532int _tr_tally OF((deflate_state *s, unsigned dist, unsigned lc));
533ulg _tr_flush_block OF((deflate_state *s, charf *buf, ulg stored_len,
534 int eof));
535void _tr_align OF((deflate_state *s));
536void _tr_stored_block OF((deflate_state *s, charf *buf, ulg stored_len,
537 int eof));
538void _tr_stored_type_only OF((deflate_state *));
539
540#endif
541/* --- deflate.h */
542
543/* +++ deflate.c */
544/* deflate.c -- compress data using the deflation algorithm
545 * Copyright (C) 1995-1996 Jean-loup Gailly.
546 * For conditions of distribution and use, see copyright notice in zlib.h
547 */
548
549/*
550 * ALGORITHM
551 *
552 * The "deflation" process depends on being able to identify portions
553 * of the input text which are identical to earlier input (within a
554 * sliding window trailing behind the input currently being processed).
555 *
556 * The most straightforward technique turns out to be the fastest for
557 * most input files: try all possible matches and select the longest.
558 * The key feature of this algorithm is that insertions into the string
559 * dictionary are very simple and thus fast, and deletions are avoided
560 * completely. Insertions are performed at each input character, whereas
561 * string matches are performed only when the previous match ends. So it
562 * is preferable to spend more time in matches to allow very fast string
563 * insertions and avoid deletions. The matching algorithm for small
564 * strings is inspired from that of Rabin & Karp. A brute force approach
565 * is used to find longer strings when a small match has been found.
566 * A similar algorithm is used in comic (by Jan-Mark Wams) and freeze
567 * (by Leonid Broukhis).
568 * A previous version of this file used a more sophisticated algorithm
569 * (by Fiala and Greene) which is guaranteed to run in linear amortized
570 * time, but has a larger average cost, uses more memory and is patented.
571 * However the F&G algorithm may be faster for some highly redundant
572 * files if the parameter max_chain_length (described below) is too large.
573 *
574 * ACKNOWLEDGEMENTS
575 *
576 * The idea of lazy evaluation of matches is due to Jan-Mark Wams, and
577 * I found it in 'freeze' written by Leonid Broukhis.
578 * Thanks to many people for bug reports and testing.
579 *
580 * REFERENCES
581 *
582 * Deutsch, L.P.,"DEFLATE Compressed Data Format Specification".
583 * Available in ftp://ds.internic.net/rfc/rfc1951.txt
584 *
585 * A description of the Rabin and Karp algorithm is given in the book
586 * "Algorithms" by R. Sedgewick, Addison-Wesley, p252.
587 *
588 * Fiala,E.R., and Greene,D.H.
589 * Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595
590 *
591 */
592
593/* From: deflate.c,v 1.15 1996/07/24 13:40:58 me Exp $ */
594
595/* #include "deflate.h" */
596
597char deflate_copyright[] = " deflate 1.0.4 Copyright 1995-1996 Jean-loup Gailly ";
598/*
599 If you use the zlib library in a product, an acknowledgment is welcome
600 in the documentation of your product. If for some reason you cannot
601 include such an acknowledgment, I would appreciate that you keep this
602 copyright string in the executable of your product.
603 */
604
605/* ===========================================================================
606 * Function prototypes.
607 */
608typedef enum {
609 need_more, /* block not completed, need more input or more output */
610 block_done, /* block flush performed */
611 finish_started, /* finish started, need only more output at next deflate */
612 finish_done /* finish done, accept no more input or output */
613} block_state;
614
615typedef block_state (*compress_func) OF((deflate_state *s, int flush));
616/* Compression function. Returns the block state after the call. */
617
618local void fill_window OF((deflate_state *s));
619local block_state deflate_stored OF((deflate_state *s, int flush));
620local block_state deflate_fast OF((deflate_state *s, int flush));
621local block_state deflate_slow OF((deflate_state *s, int flush));
622local void lm_init OF((deflate_state *s));
623local void putShortMSB OF((deflate_state *s, uInt b));
624local void flush_pending OF((z_streamp strm));
625local int read_buf OF((z_streamp strm, charf *buf, unsigned size));
626#ifdef ASMV
627 void match_init OF((void)); /* asm code initialization */
628 uInt longest_match OF((deflate_state *s, IPos cur_match));
629#else
630local uInt longest_match OF((deflate_state *s, IPos cur_match));
631#endif
632
633#ifdef DEBUG_ZLIB
634local void check_match OF((deflate_state *s, IPos start, IPos match,
635 int length));
636#endif
637
638/* ===========================================================================
639 * Local data
640 */
641
642#define NIL 0
643/* Tail of hash chains */
644
645#ifndef TOO_FAR
646# define TOO_FAR 4096
647#endif
648/* Matches of length 3 are discarded if their distance exceeds TOO_FAR */
649
650#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
651/* Minimum amount of lookahead, except at the end of the input file.
652 * See deflate.c for comments about the MIN_MATCH+1.
653 */
654
655/* Values for max_lazy_match, good_match and max_chain_length, depending on
656 * the desired pack level (0..9). The values given below have been tuned to
657 * exclude worst case performance for pathological files. Better values may be
658 * found for specific files.
659 */
660typedef struct config_s {
661 ush good_length; /* reduce lazy search above this match length */
662 ush max_lazy; /* do not perform lazy search above this match length */
663 ush nice_length; /* quit search above this match length */
664 ush max_chain;
665 compress_func func;
666} config;
667
668local config configuration_table[10] = {
669/* good lazy nice chain */
670/* 0 */ {0, 0, 0, 0, deflate_stored}, /* store only */
671/* 1 */ {4, 4, 8, 4, deflate_fast}, /* maximum speed, no lazy matches */
672/* 2 */ {4, 5, 16, 8, deflate_fast},
673/* 3 */ {4, 6, 32, 32, deflate_fast},
674
675/* 4 */ {4, 4, 16, 16, deflate_slow}, /* lazy matches */
676/* 5 */ {8, 16, 32, 32, deflate_slow},
677/* 6 */ {8, 16, 128, 128, deflate_slow},
678/* 7 */ {8, 32, 128, 256, deflate_slow},
679/* 8 */ {32, 128, 258, 1024, deflate_slow},
680/* 9 */ {32, 258, 258, 4096, deflate_slow}}; /* maximum compression */
681
682/* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4
683 * For deflate_fast() (levels <= 3) good is ignored and lazy has a different
684 * meaning.
685 */
686
687#define EQUAL 0
688/* result of memcmp for equal strings */
689
690#ifndef NO_DUMMY_DECL
691struct static_tree_desc_s {int dummy;}; /* for buggy compilers */
692#endif
693
694/* ===========================================================================
695 * Update a hash value with the given input byte
696 * IN assertion: all calls to to UPDATE_HASH are made with consecutive
697 * input characters, so that a running hash key can be computed from the
698 * previous key instead of complete recalculation each time.
699 */
700#define UPDATE_HASH(s,h,c) (h = (((h)<<s->hash_shift) ^ (c)) & s->hash_mask)
701
702
703/* ===========================================================================
704 * Insert string str in the dictionary and set match_head to the previous head
705 * of the hash chain (the most recent string with same hash key). Return
706 * the previous length of the hash chain.
707 * IN assertion: all calls to to INSERT_STRING are made with consecutive
708 * input characters and the first MIN_MATCH bytes of str are valid
709 * (except for the last MIN_MATCH-1 bytes of the input file).
710 */
711#define INSERT_STRING(s, str, match_head) \
712 (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \
713 s->prev[(str) & s->w_mask] = match_head = s->head[s->ins_h], \
714 s->head[s->ins_h] = (Pos)(str))
715
716/* ===========================================================================
717 * Initialize the hash table (avoiding 64K overflow for 16 bit systems).
718 * prev[] will be initialized on the fly.
719 */
720#define CLEAR_HASH(s) \
721 s->head[s->hash_size-1] = NIL; \
722 zmemzero((charf *)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head));
723
724/* ========================================================================= */
725int deflateInit_(strm, level, version, stream_size)
726 z_streamp strm;
727 int level;
728 const char *version;
729 int stream_size;
730{
731 return deflateInit2_(strm, level, Z_DEFLATED, MAX_WBITS, DEF_MEM_LEVEL,
732 Z_DEFAULT_STRATEGY, version, stream_size);
733 /* To do: ignore strm->next_in if we use it as window */
734}
735
736/* ========================================================================= */
737int deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
738 version, stream_size)
739 z_streamp strm;
740 int level;
741 int method;
742 int windowBits;
743 int memLevel;
744 int strategy;
745 const char *version;
746 int stream_size;
747{
748 deflate_state *s;
749 int noheader = 0;
750 static char* my_version = ZLIB_VERSION;
751
752 ushf *overlay;
753 /* We overlay pending_buf and d_buf+l_buf. This works since the average
754 * output size for (length,distance) codes is <= 24 bits.
755 */
756
757 if (version == Z_NULL || version[0] != my_version[0] ||
758 stream_size != sizeof(z_stream)) {
759 return Z_VERSION_ERROR;
760 }
761 if (strm == Z_NULL) return Z_STREAM_ERROR;
762
763 strm->msg = Z_NULL;
764#ifndef NO_ZCFUNCS
765 if (strm->zalloc == Z_NULL) {
766 strm->zalloc = zcalloc;
767 strm->opaque = (voidpf)0;
768 }
769 if (strm->zfree == Z_NULL) strm->zfree = zcfree;
770#endif
771
772 if (level == Z_DEFAULT_COMPRESSION) level = 6;
773
774 if (windowBits < 0) { /* undocumented feature: suppress zlib header */
775 noheader = 1;
776 windowBits = -windowBits;
777 }
778 if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED ||
779 windowBits < 8 || windowBits > 15 || level < 0 || level > 9 ||
780 strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
781 return Z_STREAM_ERROR;
782 }
783 s = (deflate_state *) ZALLOC(strm, 1, sizeof(deflate_state));
784 if (s == Z_NULL) return Z_MEM_ERROR;
785 strm->state = (struct internal_state FAR *)s;
786 s->strm = strm;
787
788 s->noheader = noheader;
789 s->w_bits = windowBits;
790 s->w_size = 1 << s->w_bits;
791 s->w_mask = s->w_size - 1;
792
793 s->hash_bits = memLevel + 7;
794 s->hash_size = 1 << s->hash_bits;
795 s->hash_mask = s->hash_size - 1;
796 s->hash_shift = ((s->hash_bits+MIN_MATCH-1)/MIN_MATCH);
797
798 s->window = (Bytef *) ZALLOC(strm, s->w_size, 2*sizeof(Byte));
799 s->prev = (Posf *) ZALLOC(strm, s->w_size, sizeof(Pos));
800 s->head = (Posf *) ZALLOC(strm, s->hash_size, sizeof(Pos));
801
802 s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */
803
804 overlay = (ushf *) ZALLOC(strm, s->lit_bufsize, sizeof(ush)+2);
805 s->pending_buf = (uchf *) overlay;
806 s->pending_buf_size = (ulg)s->lit_bufsize * (sizeof(ush)+2L);
807
808 if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL ||
809 s->pending_buf == Z_NULL) {
810 strm->msg = (char*)ERR_MSG(Z_MEM_ERROR);
811 deflateEnd (strm);
812 return Z_MEM_ERROR;
813 }
814 s->d_buf = overlay + s->lit_bufsize/sizeof(ush);
815 s->l_buf = s->pending_buf + (1+sizeof(ush))*s->lit_bufsize;
816
817 s->level = level;
818 s->strategy = strategy;
819 s->method = (Byte)method;
820
821 return deflateReset(strm);
822}
823
824/* ========================================================================= */
825int deflateSetDictionary (strm, dictionary, dictLength)
826 z_streamp strm;
827 const Bytef *dictionary;
828 uInt dictLength;
829{
830 deflate_state *s;
831 uInt length = dictLength;
832 uInt n;
833 IPos hash_head = 0;
834
835 if (strm == Z_NULL || strm->state == Z_NULL || dictionary == Z_NULL)
836 return Z_STREAM_ERROR;
837
838 s = (deflate_state *) strm->state;
839 if (s->status != INIT_STATE) return Z_STREAM_ERROR;
840
841 strm->adler = adler32(strm->adler, dictionary, dictLength);
842
843 if (length < MIN_MATCH) return Z_OK;
844 if (length > MAX_DIST(s)) {
845 length = MAX_DIST(s);
846#ifndef USE_DICT_HEAD
847 dictionary += dictLength - length; /* use the tail of the dictionary */
848#endif
849 }
850 zmemcpy((charf *)s->window, dictionary, length);
851 s->strstart = length;
852 s->block_start = (long)length;
853
854 /* Insert all strings in the hash table (except for the last two bytes).
855 * s->lookahead stays null, so s->ins_h will be recomputed at the next
856 * call of fill_window.
857 */
858 s->ins_h = s->window[0];
859 UPDATE_HASH(s, s->ins_h, s->window[1]);
860 for (n = 0; n <= length - MIN_MATCH; n++) {
861 INSERT_STRING(s, n, hash_head);
862 }
863 if (hash_head) hash_head = 0; /* to make compiler happy */
864 return Z_OK;
865}
866
867/* ========================================================================= */
868int deflateReset (strm)
869 z_streamp strm;
870{
871 deflate_state *s;
872
873 if (strm == Z_NULL || strm->state == Z_NULL ||
874 strm->zalloc == Z_NULL || strm->zfree == Z_NULL) return Z_STREAM_ERROR;
875
876 strm->total_in = strm->total_out = 0;
877 strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */
878 strm->data_type = Z_UNKNOWN;
879
880 s = (deflate_state *)strm->state;
881 s->pending = 0;
882 s->pending_out = s->pending_buf;
883
884 if (s->noheader < 0) {
885 s->noheader = 0; /* was set to -1 by deflate(..., Z_FINISH); */
886 }
887 s->status = s->noheader ? BUSY_STATE : INIT_STATE;
888 strm->adler = 1;
889 s->last_flush = Z_NO_FLUSH;
890
891 _tr_init(s);
892 lm_init(s);
893
894 return Z_OK;
895}
896
897/* ========================================================================= */
898int deflateParams(strm, level, strategy)
899 z_streamp strm;
900 int level;
901 int strategy;
902{
903 deflate_state *s;
904 compress_func func;
905 int err = Z_OK;
906
907 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
908 s = (deflate_state *) strm->state;
909
910 if (level == Z_DEFAULT_COMPRESSION) {
911 level = 6;
912 }
913 if (level < 0 || level > 9 || strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
914 return Z_STREAM_ERROR;
915 }
916 func = configuration_table[s->level].func;
917
918 if (func != configuration_table[level].func && strm->total_in != 0) {
919 /* Flush the last buffer: */
920 err = deflate(strm, Z_PARTIAL_FLUSH);
921 }
922 if (s->level != level) {
923 s->level = level;
924 s->max_lazy_match = configuration_table[level].max_lazy;
925 s->good_match = configuration_table[level].good_length;
926 s->nice_match = configuration_table[level].nice_length;
927 s->max_chain_length = configuration_table[level].max_chain;
928 }
929 s->strategy = strategy;
930 return err;
931}
932
933/* =========================================================================
934 * Put a short in the pending buffer. The 16-bit value is put in MSB order.
935 * IN assertion: the stream state is correct and there is enough room in
936 * pending_buf.
937 */
938local void putShortMSB (s, b)
939 deflate_state *s;
940 uInt b;
941{
942 put_byte(s, (Byte)(b >> 8));
943 put_byte(s, (Byte)(b & 0xff));
944}
945
946/* =========================================================================
947 * Flush as much pending output as possible. All deflate() output goes
948 * through this function so some applications may wish to modify it
949 * to avoid allocating a large strm->next_out buffer and copying into it.
950 * (See also read_buf()).
951 */
952local void flush_pending(strm)
953 z_streamp strm;
954{
955 deflate_state *s = (deflate_state *) strm->state;
956 unsigned len = s->pending;
957
958 if (len > strm->avail_out) len = strm->avail_out;
959 if (len == 0) return;
960
961 if (strm->next_out != Z_NULL) {
962 zmemcpy(strm->next_out, s->pending_out, len);
963 strm->next_out += len;
964 }
965 s->pending_out += len;
966 strm->total_out += len;
967 strm->avail_out -= len;
968 s->pending -= len;
969 if (s->pending == 0) {
970 s->pending_out = s->pending_buf;
971 }
972}
973
974/* ========================================================================= */
975int deflate (strm, flush)
976 z_streamp strm;
977 int flush;
978{
979 int old_flush; /* value of flush param for previous deflate call */
980 deflate_state *s;
981
982 if (strm == Z_NULL || strm->state == Z_NULL ||
983 flush > Z_FINISH || flush < 0) {
984 return Z_STREAM_ERROR;
985 }
986 s = (deflate_state *) strm->state;
987
988 if ((strm->next_in == Z_NULL && strm->avail_in != 0) ||
989 (s->status == FINISH_STATE && flush != Z_FINISH)) {
990 ERR_RETURN(strm, Z_STREAM_ERROR);
991 }
992 if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR);
993
994 s->strm = strm; /* just in case */
995 old_flush = s->last_flush;
996 s->last_flush = flush;
997
998 /* Write the zlib header */
999 if (s->status == INIT_STATE) {
1000
1001 uInt header = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8;
1002 uInt level_flags = (s->level-1) >> 1;
1003
1004 if (level_flags > 3) level_flags = 3;
1005 header |= (level_flags << 6);
1006 if (s->strstart != 0) header |= PRESET_DICT;
1007 header += 31 - (header % 31);
1008
1009 s->status = BUSY_STATE;
1010 putShortMSB(s, header);
1011
1012 /* Save the adler32 of the preset dictionary: */
1013 if (s->strstart != 0) {
1014 putShortMSB(s, (uInt)(strm->adler >> 16));
1015 putShortMSB(s, (uInt)(strm->adler & 0xffff));
1016 }
1017 strm->adler = 1L;
1018 }
1019
1020 /* Flush as much pending output as possible */
1021 if (s->pending != 0) {
1022 flush_pending(strm);
1023 if (strm->avail_out == 0) {
1024 /* Since avail_out is 0, deflate will be called again with
1025 * more output space, but possibly with both pending and
1026 * avail_in equal to zero. There won't be anything to do,
1027 * but this is not an error situation so make sure we
1028 * return OK instead of BUF_ERROR at next call of deflate:
1029 */
1030 s->last_flush = -1;
1031 return Z_OK;
1032 }
1033
1034 /* Make sure there is something to do and avoid duplicate consecutive
1035 * flushes. For repeated and useless calls with Z_FINISH, we keep
1036 * returning Z_STREAM_END instead of Z_BUFF_ERROR.
1037 */
1038 } else if (strm->avail_in == 0 && flush <= old_flush &&
1039 flush != Z_FINISH) {
1040 ERR_RETURN(strm, Z_BUF_ERROR);
1041 }
1042
1043 /* User must not provide more input after the first FINISH: */
1044 if (s->status == FINISH_STATE && strm->avail_in != 0) {
1045 ERR_RETURN(strm, Z_BUF_ERROR);
1046 }
1047
1048 /* Start a new block or continue the current one.
1049 */
1050 if (strm->avail_in != 0 || s->lookahead != 0 ||
1051 (flush != Z_NO_FLUSH && s->status != FINISH_STATE)) {
1052 block_state bstate;
1053
1054 bstate = (*(configuration_table[s->level].func))(s, flush);
1055
1056 if (bstate == finish_started || bstate == finish_done) {
1057 s->status = FINISH_STATE;
1058 }
1059 if (bstate == need_more || bstate == finish_started) {
1060 if (strm->avail_out == 0) {
1061 s->last_flush = -1; /* avoid BUF_ERROR next call, see above */
1062 }
1063 return Z_OK;
1064 /* If flush != Z_NO_FLUSH && avail_out == 0, the next call
1065 * of deflate should use the same flush parameter to make sure
1066 * that the flush is complete. So we don't have to output an
1067 * empty block here, this will be done at next call. This also
1068 * ensures that for a very small output buffer, we emit at most
1069 * one empty block.
1070 */
1071 }
1072 if (bstate == block_done) {
1073 if (flush == Z_PARTIAL_FLUSH) {
1074 _tr_align(s);
1075 } else if (flush == Z_PACKET_FLUSH) {
1076 /* Output just the 3-bit `stored' block type value,
1077 but not a zero length. */
1078 _tr_stored_type_only(s);
1079 } else { /* FULL_FLUSH or SYNC_FLUSH */
1080 _tr_stored_block(s, (char*)0, 0L, 0);
1081 /* For a full flush, this empty block will be recognized
1082 * as a special marker by inflate_sync().
1083 */
1084 if (flush == Z_FULL_FLUSH) {
1085 CLEAR_HASH(s); /* forget history */
1086 }
1087 }
1088 flush_pending(strm);
1089 if (strm->avail_out == 0) {
1090 s->last_flush = -1; /* avoid BUF_ERROR at next call, see above */
1091 return Z_OK;
1092 }
1093 }
1094 }
1095 Assert(strm->avail_out > 0, "bug2");
1096
1097 if (flush != Z_FINISH) return Z_OK;
1098 if (s->noheader) return Z_STREAM_END;
1099
1100 /* Write the zlib trailer (adler32) */
1101 putShortMSB(s, (uInt)(strm->adler >> 16));
1102 putShortMSB(s, (uInt)(strm->adler & 0xffff));
1103 flush_pending(strm);
1104 /* If avail_out is zero, the application will call deflate again
1105 * to flush the rest.
1106 */
1107 s->noheader = -1; /* write the trailer only once! */
1108 return s->pending != 0 ? Z_OK : Z_STREAM_END;
1109}
1110
1111/* ========================================================================= */
1112int deflateEnd (strm)
1113 z_streamp strm;
1114{
1115 int status;
1116 deflate_state *s;
1117
1118 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
1119 s = (deflate_state *) strm->state;
1120
1121 status = s->status;
1122 if (status != INIT_STATE && status != BUSY_STATE &&
1123 status != FINISH_STATE) {
1124 return Z_STREAM_ERROR;
1125 }
1126
1127 /* Deallocate in reverse order of allocations: */
1128 TRY_FREE(strm, s->pending_buf);
1129 TRY_FREE(strm, s->head);
1130 TRY_FREE(strm, s->prev);
1131 TRY_FREE(strm, s->window);
1132
1133 ZFREE(strm, s);
1134 strm->state = Z_NULL;
1135
1136 return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK;
1137}
1138
1139/* =========================================================================
1140 * Copy the source state to the destination state.
1141 */
1142int deflateCopy (dest, source)
1143 z_streamp dest;
1144 z_streamp source;
1145{
1146 deflate_state *ds;
1147 deflate_state *ss;
1148 ushf *overlay;
1149
1150 if (source == Z_NULL || dest == Z_NULL || source->state == Z_NULL)
1151 return Z_STREAM_ERROR;
1152 ss = (deflate_state *) source->state;
1153
1154 zmemcpy(dest, source, sizeof(*dest));
1155
1156 ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state));
1157 if (ds == Z_NULL) return Z_MEM_ERROR;
1158 dest->state = (struct internal_state FAR *) ds;
1159 zmemcpy(ds, ss, sizeof(*ds));
1160 ds->strm = dest;
1161
1162 ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte));
1163 ds->prev = (Posf *) ZALLOC(dest, ds->w_size, sizeof(Pos));
1164 ds->head = (Posf *) ZALLOC(dest, ds->hash_size, sizeof(Pos));
1165 overlay = (ushf *) ZALLOC(dest, ds->lit_bufsize, sizeof(ush)+2);
1166 ds->pending_buf = (uchf *) overlay;
1167
1168 if (ds->window == Z_NULL || ds->prev == Z_NULL || ds->head == Z_NULL ||
1169 ds->pending_buf == Z_NULL) {
1170 deflateEnd (dest);
1171 return Z_MEM_ERROR;
1172 }
1173 /* ??? following zmemcpy doesn't work for 16-bit MSDOS */
1174 zmemcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte));
1175 zmemcpy(ds->prev, ss->prev, ds->w_size * sizeof(Pos));
1176 zmemcpy(ds->head, ss->head, ds->hash_size * sizeof(Pos));
1177 zmemcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size);
1178
1179 ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf);
1180 ds->d_buf = overlay + ds->lit_bufsize/sizeof(ush);
1181 ds->l_buf = ds->pending_buf + (1+sizeof(ush))*ds->lit_bufsize;
1182
1183 ds->l_desc.dyn_tree = ds->dyn_ltree;
1184 ds->d_desc.dyn_tree = ds->dyn_dtree;
1185 ds->bl_desc.dyn_tree = ds->bl_tree;
1186
1187 return Z_OK;
1188}
1189
1190/* ===========================================================================
1191 * Return the number of bytes of output which are immediately available
1192 * for output from the decompressor.
1193 */
1194int deflateOutputPending (strm)
1195 z_streamp strm;
1196{
1197 if (strm == Z_NULL || strm->state == Z_NULL) return 0;
1198
1199 return ((deflate_state *)(strm->state))->pending;
1200}
1201
1202/* ===========================================================================
1203 * Read a new buffer from the current input stream, update the adler32
1204 * and total number of bytes read. All deflate() input goes through
1205 * this function so some applications may wish to modify it to avoid
1206 * allocating a large strm->next_in buffer and copying from it.
1207 * (See also flush_pending()).
1208 */
1209local int read_buf(strm, buf, size)
1210 z_streamp strm;
1211 charf *buf;
1212 unsigned size;
1213{
1214 unsigned len = strm->avail_in;
1215
1216 if (len > size) len = size;
1217 if (len == 0) return 0;
1218
1219 strm->avail_in -= len;
1220
1221 if (!((deflate_state *)(strm->state))->noheader) {
1222 strm->adler = adler32(strm->adler, strm->next_in, len);
1223 }
1224 zmemcpy(buf, strm->next_in, len);
1225 strm->next_in += len;
1226 strm->total_in += len;
1227
1228 return (int)len;
1229}
1230
1231/* ===========================================================================
1232 * Initialize the "longest match" routines for a new zlib stream
1233 */
1234local void lm_init (s)
1235 deflate_state *s;
1236{
1237 s->window_size = (ulg)2L*s->w_size;
1238
1239 CLEAR_HASH(s);
1240
1241 /* Set the default configuration parameters:
1242 */
1243 s->max_lazy_match = configuration_table[s->level].max_lazy;
1244 s->good_match = configuration_table[s->level].good_length;
1245 s->nice_match = configuration_table[s->level].nice_length;
1246 s->max_chain_length = configuration_table[s->level].max_chain;
1247
1248 s->strstart = 0;
1249 s->block_start = 0L;
1250 s->lookahead = 0;
1251 s->match_length = s->prev_length = MIN_MATCH-1;
1252 s->match_available = 0;
1253 s->ins_h = 0;
1254#ifdef ASMV
1255 match_init(); /* initialize the asm code */
1256#endif
1257}
1258
1259/* ===========================================================================
1260 * Set match_start to the longest match starting at the given string and
1261 * return its length. Matches shorter or equal to prev_length are discarded,
1262 * in which case the result is equal to prev_length and match_start is
1263 * garbage.
1264 * IN assertions: cur_match is the head of the hash chain for the current
1265 * string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1
1266 * OUT assertion: the match length is not greater than s->lookahead.
1267 */
1268#ifndef ASMV
1269/* For 80x86 and 680x0, an optimized version will be provided in match.asm or
1270 * match.S. The code will be functionally equivalent.
1271 */
1272local uInt longest_match(s, cur_match)
1273 deflate_state *s;
1274 IPos cur_match; /* current match */
1275{
1276 unsigned chain_length = s->max_chain_length;/* max hash chain length */
1277 register Bytef *scan = s->window + s->strstart; /* current string */
1278 register Bytef *match; /* matched string */
1279 register int len; /* length of current match */
1280 int best_len = s->prev_length; /* best match length so far */
1281 int nice_match = s->nice_match; /* stop if match long enough */
1282 IPos limit = s->strstart > (IPos)MAX_DIST(s) ?
1283 s->strstart - (IPos)MAX_DIST(s) : NIL;
1284 /* Stop when cur_match becomes <= limit. To simplify the code,
1285 * we prevent matches with the string of window index 0.
1286 */
1287 Posf *prev = s->prev;
1288 uInt wmask = s->w_mask;
1289
1290#ifdef UNALIGNED_OK
1291 /* Compare two bytes at a time. Note: this is not always beneficial.
1292 * Try with and without -DUNALIGNED_OK to check.
1293 */
1294 register Bytef *strend = s->window + s->strstart + MAX_MATCH - 1;
1295 register ush scan_start = *(ushf*)scan;
1296 register ush scan_end = *(ushf*)(scan+best_len-1);
1297#else
1298 register Bytef *strend = s->window + s->strstart + MAX_MATCH;
1299 register Byte scan_end1 = scan[best_len-1];
1300 register Byte scan_end = scan[best_len];
1301#endif
1302
1303 /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
1304 * It is easy to get rid of this optimization if necessary.
1305 */
1306 Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");
1307
1308 /* Do not waste too much time if we already have a good match: */
1309 if (s->prev_length >= s->good_match) {
1310 chain_length >>= 2;
1311 }
1312 /* Do not look for matches beyond the end of the input. This is necessary
1313 * to make deflate deterministic.
1314 */
1315 if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;
1316
1317 Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
1318
1319 do {
1320 Assert(cur_match < s->strstart, "no future");
1321 match = s->window + cur_match;
1322
1323 /* Skip to next match if the match length cannot increase
1324 * or if the match length is less than 2:
1325 */
1326#if (defined(UNALIGNED_OK) && MAX_MATCH == 258)
1327 /* This code assumes sizeof(unsigned short) == 2. Do not use
1328 * UNALIGNED_OK if your compiler uses a different size.
1329 */
1330 if (*(ushf*)(match+best_len-1) != scan_end ||
1331 *(ushf*)match != scan_start) continue;
1332
1333 /* It is not necessary to compare scan[2] and match[2] since they are
1334 * always equal when the other bytes match, given that the hash keys
1335 * are equal and that HASH_BITS >= 8. Compare 2 bytes at a time at
1336 * strstart+3, +5, ... up to strstart+257. We check for insufficient
1337 * lookahead only every 4th comparison; the 128th check will be made
1338 * at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is
1339 * necessary to put more guard bytes at the end of the window, or
1340 * to check more often for insufficient lookahead.
1341 */
1342 Assert(scan[2] == match[2], "scan[2]?");
1343 scan++, match++;
1344 do {
1345 } while (*(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1346 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1347 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1348 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1349 scan < strend);
1350 /* The funny "do {}" generates better code on most compilers */
1351
1352 /* Here, scan <= window+strstart+257 */
1353 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1354 if (*scan == *match) scan++;
1355
1356 len = (MAX_MATCH - 1) - (int)(strend-scan);
1357 scan = strend - (MAX_MATCH-1);
1358
1359#else /* UNALIGNED_OK */
1360
1361 if (match[best_len] != scan_end ||
1362 match[best_len-1] != scan_end1 ||
1363 *match != *scan ||
1364 *++match != scan[1]) continue;
1365
1366 /* The check at best_len-1 can be removed because it will be made
1367 * again later. (This heuristic is not always a win.)
1368 * It is not necessary to compare scan[2] and match[2] since they
1369 * are always equal when the other bytes match, given that
1370 * the hash keys are equal and that HASH_BITS >= 8.
1371 */
1372 scan += 2, match++;
1373 Assert(*scan == *match, "match[2]?");
1374
1375 /* We check for insufficient lookahead only every 8th comparison;
1376 * the 256th check will be made at strstart+258.
1377 */
1378 do {
1379 } while (*++scan == *++match && *++scan == *++match &&
1380 *++scan == *++match && *++scan == *++match &&
1381 *++scan == *++match && *++scan == *++match &&
1382 *++scan == *++match && *++scan == *++match &&
1383 scan < strend);
1384
1385 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1386
1387 len = MAX_MATCH - (int)(strend - scan);
1388 scan = strend - MAX_MATCH;
1389
1390#endif /* UNALIGNED_OK */
1391
1392 if (len > best_len) {
1393 s->match_start = cur_match;
1394 best_len = len;
1395 if (len >= nice_match) break;
1396#ifdef UNALIGNED_OK
1397 scan_end = *(ushf*)(scan+best_len-1);
1398#else
1399 scan_end1 = scan[best_len-1];
1400 scan_end = scan[best_len];
1401#endif
1402 }
1403 } while ((cur_match = prev[cur_match & wmask]) > limit
1404 && --chain_length != 0);
1405
1406 if ((uInt)best_len <= s->lookahead) return best_len;
1407 return s->lookahead;
1408}
1409#endif /* ASMV */
1410
1411#ifdef DEBUG_ZLIB
1412/* ===========================================================================
1413 * Check that the match at match_start is indeed a match.
1414 */
1415local void check_match(s, start, match, length)
1416 deflate_state *s;
1417 IPos start, match;
1418 int length;
1419{
1420 /* check that the match is indeed a match */
1421 if (zmemcmp((charf *)s->window + match,
1422 (charf *)s->window + start, length) != EQUAL) {
1423 fprintf(stderr, " start %u, match %u, length %d\n",
1424 start, match, length);
1425 do {
1426 fprintf(stderr, "%c%c", s->window[match++], s->window[start++]);
1427 } while (--length != 0);
1428 z_error("invalid match");
1429 }
1430 if (z_verbose > 1) {
1431 fprintf(stderr,"\\[%d,%d]", start-match, length);
1432 do { putc(s->window[start++], stderr); } while (--length != 0);
1433 }
1434}
1435#else
1436# define check_match(s, start, match, length)
1437#endif
1438
1439/* ===========================================================================
1440 * Fill the window when the lookahead becomes insufficient.
1441 * Updates strstart and lookahead.
1442 *
1443 * IN assertion: lookahead < MIN_LOOKAHEAD
1444 * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD
1445 * At least one byte has been read, or avail_in == 0; reads are
1446 * performed for at least two bytes (required for the zip translate_eol
1447 * option -- not supported here).
1448 */
1449local void fill_window(s)
1450 deflate_state *s;
1451{
1452 register unsigned n, m;
1453 register Posf *p;
1454 unsigned more; /* Amount of free space at the end of the window. */
1455 uInt wsize = s->w_size;
1456
1457 do {
1458 more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart);
1459
1460 /* Deal with !@#$% 64K limit: */
1461 if (more == 0 && s->strstart == 0 && s->lookahead == 0) {
1462 more = wsize;
1463
1464 } else if (more == (unsigned)(-1)) {
1465 /* Very unlikely, but possible on 16 bit machine if strstart == 0
1466 * and lookahead == 1 (input done one byte at time)
1467 */
1468 more--;
1469
1470 /* If the window is almost full and there is insufficient lookahead,
1471 * move the upper half to the lower one to make room in the upper half.
1472 */
1473 } else if (s->strstart >= wsize+MAX_DIST(s)) {
1474
1475 zmemcpy((charf *)s->window, (charf *)s->window+wsize,
1476 (unsigned)wsize);
1477 s->match_start -= wsize;
1478 s->strstart -= wsize; /* we now have strstart >= MAX_DIST */
1479 s->block_start -= (long) wsize;
1480
1481 /* Slide the hash table (could be avoided with 32 bit values
1482 at the expense of memory usage). We slide even when level == 0
1483 to keep the hash table consistent if we switch back to level > 0
1484 later. (Using level 0 permanently is not an optimal usage of
1485 zlib, so we don't care about this pathological case.)
1486 */
1487 n = s->hash_size;
1488 p = &s->head[n];
1489 do {
1490 m = *--p;
1491 *p = (Pos)(m >= wsize ? m-wsize : NIL);
1492 } while (--n);
1493
1494 n = wsize;
1495 p = &s->prev[n];
1496 do {
1497 m = *--p;
1498 *p = (Pos)(m >= wsize ? m-wsize : NIL);
1499 /* If n is not on any hash chain, prev[n] is garbage but
1500 * its value will never be used.
1501 */
1502 } while (--n);
1503 more += wsize;
1504 }
1505 if (s->strm->avail_in == 0) return;
1506
1507 /* If there was no sliding:
1508 * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 &&
1509 * more == window_size - lookahead - strstart
1510 * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1)
1511 * => more >= window_size - 2*WSIZE + 2
1512 * In the BIG_MEM or MMAP case (not yet supported),
1513 * window_size == input_size + MIN_LOOKAHEAD &&
1514 * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD.
1515 * Otherwise, window_size == 2*WSIZE so more >= 2.
1516 * If there was sliding, more >= WSIZE. So in all cases, more >= 2.
1517 */
1518 Assert(more >= 2, "more < 2");
1519
1520 n = read_buf(s->strm, (charf *)s->window + s->strstart + s->lookahead,
1521 more);
1522 s->lookahead += n;
1523
1524 /* Initialize the hash value now that we have some input: */
1525 if (s->lookahead >= MIN_MATCH) {
1526 s->ins_h = s->window[s->strstart];
1527 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
1528#if MIN_MATCH != 3
1529 Call UPDATE_HASH() MIN_MATCH-3 more times
1530#endif
1531 }
1532 /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage,
1533 * but this is not important since only literal bytes will be emitted.
1534 */
1535
1536 } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0);
1537}
1538
1539/* ===========================================================================
1540 * Flush the current block, with given end-of-file flag.
1541 * IN assertion: strstart is set to the end of the current match.
1542 */
1543#define FLUSH_BLOCK_ONLY(s, eof) { \
1544 _tr_flush_block(s, (s->block_start >= 0L ? \
1545 (charf *)&s->window[(unsigned)s->block_start] : \
1546 (charf *)Z_NULL), \
1547 (ulg)((long)s->strstart - s->block_start), \
1548 (eof)); \
1549 s->block_start = s->strstart; \
1550 flush_pending(s->strm); \
1551 Tracev((stderr,"[FLUSH]")); \
1552}
1553
1554/* Same but force premature exit if necessary. */
1555#define FLUSH_BLOCK(s, eof) { \
1556 FLUSH_BLOCK_ONLY(s, eof); \
1557 if (s->strm->avail_out == 0) return (eof) ? finish_started : need_more; \
1558}
1559
1560/* ===========================================================================
1561 * Copy without compression as much as possible from the input stream, return
1562 * the current block state.
1563 * This function does not insert new strings in the dictionary since
1564 * uncompressible data is probably not useful. This function is used
1565 * only for the level=0 compression option.
1566 * NOTE: this function should be optimized to avoid extra copying from
1567 * window to pending_buf.
1568 */
1569local block_state deflate_stored(s, flush)
1570 deflate_state *s;
1571 int flush;
1572{
1573 /* Stored blocks are limited to 0xffff bytes, pending_buf is limited
1574 * to pending_buf_size, and each stored block has a 5 byte header:
1575 */
1576 ulg max_block_size = 0xffff;
1577 ulg max_start;
1578
1579 if (max_block_size > s->pending_buf_size - 5) {
1580 max_block_size = s->pending_buf_size - 5;
1581 }
1582
1583 /* Copy as much as possible from input to output: */
1584 for (;;) {
1585 /* Fill the window as much as possible: */
1586 if (s->lookahead <= 1) {
1587
1588 Assert(s->strstart < s->w_size+MAX_DIST(s) ||
1589 s->block_start >= (long)s->w_size, "slide too late");
1590
1591 fill_window(s);
1592 if (s->lookahead == 0 && flush == Z_NO_FLUSH) return need_more;
1593
1594 if (s->lookahead == 0) break; /* flush the current block */
1595 }
1596 Assert(s->block_start >= 0L, "block gone");
1597
1598 s->strstart += s->lookahead;
1599 s->lookahead = 0;
1600
1601 /* Emit a stored block if pending_buf will be full: */
1602 max_start = s->block_start + max_block_size;
1603 if (s->strstart == 0 || (ulg)s->strstart >= max_start) {
1604 /* strstart == 0 is possible when wraparound on 16-bit machine */
1605 s->lookahead = (uInt)(s->strstart - max_start);
1606 s->strstart = (uInt)max_start;
1607 FLUSH_BLOCK(s, 0);
1608 }
1609 /* Flush if we may have to slide, otherwise block_start may become
1610 * negative and the data will be gone:
1611 */
1612 if (s->strstart - (uInt)s->block_start >= MAX_DIST(s)) {
1613 FLUSH_BLOCK(s, 0);
1614 }
1615 }
1616 FLUSH_BLOCK(s, flush == Z_FINISH);
1617 return flush == Z_FINISH ? finish_done : block_done;
1618}
1619
1620/* ===========================================================================
1621 * Compress as much as possible from the input stream, return the current
1622 * block state.
1623 * This function does not perform lazy evaluation of matches and inserts
1624 * new strings in the dictionary only for unmatched strings or for short
1625 * matches. It is used only for the fast compression options.
1626 */
1627local block_state deflate_fast(s, flush)
1628 deflate_state *s;
1629 int flush;
1630{
1631 IPos hash_head = NIL; /* head of the hash chain */
1632 int bflush; /* set if current block must be flushed */
1633
1634 for (;;) {
1635 /* Make sure that we always have enough lookahead, except
1636 * at the end of the input file. We need MAX_MATCH bytes
1637 * for the next match, plus MIN_MATCH bytes to insert the
1638 * string following the next match.
1639 */
1640 if (s->lookahead < MIN_LOOKAHEAD) {
1641 fill_window(s);
1642 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
1643 return need_more;
1644 }
1645 if (s->lookahead == 0) break; /* flush the current block */
1646 }
1647
1648 /* Insert the string window[strstart .. strstart+2] in the
1649 * dictionary, and set hash_head to the head of the hash chain:
1650 */
1651 if (s->lookahead >= MIN_MATCH) {
1652 INSERT_STRING(s, s->strstart, hash_head);
1653 }
1654
1655 /* Find the longest match, discarding those <= prev_length.
1656 * At this point we have always match_length < MIN_MATCH
1657 */
1658 if (hash_head != NIL && s->strstart - hash_head <= MAX_DIST(s)) {
1659 /* To simplify the code, we prevent matches with the string
1660 * of window index 0 (in particular we have to avoid a match
1661 * of the string with itself at the start of the input file).
1662 */
1663 if (s->strategy != Z_HUFFMAN_ONLY) {
1664 s->match_length = longest_match (s, hash_head);
1665 }
1666 /* longest_match() sets match_start */
1667 }
1668 if (s->match_length >= MIN_MATCH) {
1669 check_match(s, s->strstart, s->match_start, s->match_length);
1670
1671 bflush = _tr_tally(s, s->strstart - s->match_start,
1672 s->match_length - MIN_MATCH);
1673
1674 s->lookahead -= s->match_length;
1675
1676 /* Insert new strings in the hash table only if the match length
1677 * is not too large. This saves time but degrades compression.
1678 */
1679 if (s->match_length <= s->max_insert_length &&
1680 s->lookahead >= MIN_MATCH) {
1681 s->match_length--; /* string at strstart already in hash table */
1682 do {
1683 s->strstart++;
1684 INSERT_STRING(s, s->strstart, hash_head);
1685 /* strstart never exceeds WSIZE-MAX_MATCH, so there are
1686 * always MIN_MATCH bytes ahead.
1687 */
1688 } while (--s->match_length != 0);
1689 s->strstart++;
1690 } else {
1691 s->strstart += s->match_length;
1692 s->match_length = 0;
1693 s->ins_h = s->window[s->strstart];
1694 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
1695#if MIN_MATCH != 3
1696 Call UPDATE_HASH() MIN_MATCH-3 more times
1697#endif
1698 /* If lookahead < MIN_MATCH, ins_h is garbage, but it does not
1699 * matter since it will be recomputed at next deflate call.
1700 */
1701 }
1702 } else {
1703 /* No match, output a literal byte */
1704 Tracevv((stderr,"%c", s->window[s->strstart]));
1705 bflush = _tr_tally (s, 0, s->window[s->strstart]);
1706 s->lookahead--;
1707 s->strstart++;
1708 }
1709 if (bflush) FLUSH_BLOCK(s, 0);
1710 }
1711 FLUSH_BLOCK(s, flush == Z_FINISH);
1712 return flush == Z_FINISH ? finish_done : block_done;
1713}
1714
1715/* ===========================================================================
1716 * Same as above, but achieves better compression. We use a lazy
1717 * evaluation for matches: a match is finally adopted only if there is
1718 * no better match at the next window position.
1719 */
1720local block_state deflate_slow(s, flush)
1721 deflate_state *s;
1722 int flush;
1723{
1724 IPos hash_head = NIL; /* head of hash chain */
1725 int bflush; /* set if current block must be flushed */
1726
1727 /* Process the input block. */
1728 for (;;) {
1729 /* Make sure that we always have enough lookahead, except
1730 * at the end of the input file. We need MAX_MATCH bytes
1731 * for the next match, plus MIN_MATCH bytes to insert the
1732 * string following the next match.
1733 */
1734 if (s->lookahead < MIN_LOOKAHEAD) {
1735 fill_window(s);
1736 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
1737 return need_more;
1738 }
1739 if (s->lookahead == 0) break; /* flush the current block */
1740 }
1741
1742 /* Insert the string window[strstart .. strstart+2] in the
1743 * dictionary, and set hash_head to the head of the hash chain:
1744 */
1745 if (s->lookahead >= MIN_MATCH) {
1746 INSERT_STRING(s, s->strstart, hash_head);
1747 }
1748
1749 /* Find the longest match, discarding those <= prev_length.
1750 */
1751 s->prev_length = s->match_length, s->prev_match = s->match_start;
1752 s->match_length = MIN_MATCH-1;
1753
1754 if (hash_head != NIL && s->prev_length < s->max_lazy_match &&
1755 s->strstart - hash_head <= MAX_DIST(s)) {
1756 /* To simplify the code, we prevent matches with the string
1757 * of window index 0 (in particular we have to avoid a match
1758 * of the string with itself at the start of the input file).
1759 */
1760 if (s->strategy != Z_HUFFMAN_ONLY) {
1761 s->match_length = longest_match (s, hash_head);
1762 }
1763 /* longest_match() sets match_start */
1764
1765 if (s->match_length <= 5 && (s->strategy == Z_FILTERED ||
1766 (s->match_length == MIN_MATCH &&
1767 s->strstart - s->match_start > TOO_FAR))) {
1768
1769 /* If prev_match is also MIN_MATCH, match_start is garbage
1770 * but we will ignore the current match anyway.
1771 */
1772 s->match_length = MIN_MATCH-1;
1773 }
1774 }
1775 /* If there was a match at the previous step and the current
1776 * match is not better, output the previous match:
1777 */
1778 if (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) {
1779 uInt max_insert = s->strstart + s->lookahead - MIN_MATCH;
1780 /* Do not insert strings in hash table beyond this. */
1781
1782 check_match(s, s->strstart-1, s->prev_match, s->prev_length);
1783
1784 bflush = _tr_tally(s, s->strstart -1 - s->prev_match,
1785 s->prev_length - MIN_MATCH);
1786
1787 /* Insert in hash table all strings up to the end of the match.
1788 * strstart-1 and strstart are already inserted. If there is not
1789 * enough lookahead, the last two strings are not inserted in
1790 * the hash table.
1791 */
1792 s->lookahead -= s->prev_length-1;
1793 s->prev_length -= 2;
1794 do {
1795 if (++s->strstart <= max_insert) {
1796 INSERT_STRING(s, s->strstart, hash_head);
1797 }
1798 } while (--s->prev_length != 0);
1799 s->match_available = 0;
1800 s->match_length = MIN_MATCH-1;
1801 s->strstart++;
1802
1803 if (bflush) FLUSH_BLOCK(s, 0);
1804
1805 } else if (s->match_available) {
1806 /* If there was no match at the previous position, output a
1807 * single literal. If there was a match but the current match
1808 * is longer, truncate the previous match to a single literal.
1809 */
1810 Tracevv((stderr,"%c", s->window[s->strstart-1]));
1811 if (_tr_tally (s, 0, s->window[s->strstart-1])) {
1812 FLUSH_BLOCK_ONLY(s, 0);
1813 }
1814 s->strstart++;
1815 s->lookahead--;
1816 if (s->strm->avail_out == 0) return need_more;
1817 } else {
1818 /* There is no previous match to compare with, wait for
1819 * the next step to decide.
1820 */
1821 s->match_available = 1;
1822 s->strstart++;
1823 s->lookahead--;
1824 }
1825 }
1826 Assert (flush != Z_NO_FLUSH, "no flush?");
1827 if (s->match_available) {
1828 Tracevv((stderr,"%c", s->window[s->strstart-1]));
1829 _tr_tally (s, 0, s->window[s->strstart-1]);
1830 s->match_available = 0;
1831 }
1832 FLUSH_BLOCK(s, flush == Z_FINISH);
1833 return flush == Z_FINISH ? finish_done : block_done;
1834}
1835/* --- deflate.c */
1836
1837/* +++ trees.c */
1838/* trees.c -- output deflated data using Huffman coding
1839 * Copyright (C) 1995-1996 Jean-loup Gailly
1840 * For conditions of distribution and use, see copyright notice in zlib.h
1841 */
1842
1843/*
1844 * ALGORITHM
1845 *
1846 * The "deflation" process uses several Huffman trees. The more
1847 * common source values are represented by shorter bit sequences.
1848 *
1849 * Each code tree is stored in a compressed form which is itself
1850 * a Huffman encoding of the lengths of all the code strings (in
1851 * ascending order by source values). The actual code strings are
1852 * reconstructed from the lengths in the inflate process, as described
1853 * in the deflate specification.
1854 *
1855 * REFERENCES
1856 *
1857 * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification".
1858 * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc
1859 *
1860 * Storer, James A.
1861 * Data Compression: Methods and Theory, pp. 49-50.
1862 * Computer Science Press, 1988. ISBN 0-7167-8156-5.
1863 *
1864 * Sedgewick, R.
1865 * Algorithms, p290.
1866 * Addison-Wesley, 1983. ISBN 0-201-06672-6.
1867 */
1868
1869/* From: trees.c,v 1.11 1996/07/24 13:41:06 me Exp $ */
1870
1871/* #include "deflate.h" */
1872
1873#ifdef DEBUG_ZLIB
1874# include <ctype.h>
1875#endif
1876
1877/* ===========================================================================
1878 * Constants
1879 */
1880
1881#define MAX_BL_BITS 7
1882/* Bit length codes must not exceed MAX_BL_BITS bits */
1883
1884#define END_BLOCK 256
1885/* end of block literal code */
1886
1887#define REP_3_6 16
1888/* repeat previous bit length 3-6 times (2 bits of repeat count) */
1889
1890#define REPZ_3_10 17
1891/* repeat a zero length 3-10 times (3 bits of repeat count) */
1892
1893#define REPZ_11_138 18
1894/* repeat a zero length 11-138 times (7 bits of repeat count) */
1895
1896local int extra_lbits[LENGTH_CODES] /* extra bits for each length code */
1897 = {0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0};
1898
1899local int extra_dbits[D_CODES] /* extra bits for each distance code */
1900 = {0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13};
1901
1902local int extra_blbits[BL_CODES]/* extra bits for each bit length code */
1903 = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7};
1904
1905local uch bl_order[BL_CODES]
1906 = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15};
1907/* The lengths of the bit length codes are sent in order of decreasing
1908 * probability, to avoid transmitting the lengths for unused bit length codes.
1909 */
1910
1911#define Buf_size (8 * 2*sizeof(char))
1912/* Number of bits used within bi_buf. (bi_buf might be implemented on
1913 * more than 16 bits on some systems.)
1914 */
1915
1916/* ===========================================================================
1917 * Local data. These are initialized only once.
1918 */
1919
1920local ct_data static_ltree[L_CODES+2];
1921/* The static literal tree. Since the bit lengths are imposed, there is no
1922 * need for the L_CODES extra codes used during heap construction. However
1923 * The codes 286 and 287 are needed to build a canonical tree (see _tr_init
1924 * below).
1925 */
1926
1927local ct_data static_dtree[D_CODES];
1928/* The static distance tree. (Actually a trivial tree since all codes use
1929 * 5 bits.)
1930 */
1931
1932local uch dist_code[512];
1933/* distance codes. The first 256 values correspond to the distances
1934 * 3 .. 258, the last 256 values correspond to the top 8 bits of
1935 * the 15 bit distances.
1936 */
1937
1938local uch length_code[MAX_MATCH-MIN_MATCH+1];
1939/* length code for each normalized match length (0 == MIN_MATCH) */
1940
1941local int base_length[LENGTH_CODES];
1942/* First normalized length for each code (0 = MIN_MATCH) */
1943
1944local int base_dist[D_CODES];
1945/* First normalized distance for each code (0 = distance of 1) */
1946
1947struct static_tree_desc_s {
1948 ct_data *static_tree; /* static tree or NULL */
1949 intf *extra_bits; /* extra bits for each code or NULL */
1950 int extra_base; /* base index for extra_bits */
1951 int elems; /* max number of elements in the tree */
1952 int max_length; /* max bit length for the codes */
1953};
1954
1955local static_tree_desc static_l_desc =
1956{static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS};
1957
1958local static_tree_desc static_d_desc =
1959{static_dtree, extra_dbits, 0, D_CODES, MAX_BITS};
1960
1961local static_tree_desc static_bl_desc =
1962{(ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS};
1963
1964/* ===========================================================================
1965 * Local (static) routines in this file.
1966 */
1967
1968local void tr_static_init OF((void));
1969local void init_block OF((deflate_state *s));
1970local void pqdownheap OF((deflate_state *s, ct_data *tree, int k));
1971local void gen_bitlen OF((deflate_state *s, tree_desc *desc));
1972local void gen_codes OF((ct_data *tree, int max_code, ushf *bl_count));
1973local void build_tree OF((deflate_state *s, tree_desc *desc));
1974local void scan_tree OF((deflate_state *s, ct_data *tree, int max_code));
1975local void send_tree OF((deflate_state *s, ct_data *tree, int max_code));
1976local int build_bl_tree OF((deflate_state *s));
1977local void send_all_trees OF((deflate_state *s, int lcodes, int dcodes,
1978 int blcodes));
1979local void compress_block OF((deflate_state *s, ct_data *ltree,
1980 ct_data *dtree));
1981local void set_data_type OF((deflate_state *s));
1982local unsigned bi_reverse OF((unsigned value, int length));
1983local void bi_windup OF((deflate_state *s));
1984local void bi_flush OF((deflate_state *s));
1985local void copy_block OF((deflate_state *s, charf *buf, unsigned len,
1986 int header));
1987
1988#ifndef DEBUG_ZLIB
1989# define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len)
1990 /* Send a code of the given tree. c and tree must not have side effects */
1991
1992#else /* DEBUG_ZLIB */
1993# define send_code(s, c, tree) \
1994 { if (verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \
1995 send_bits(s, tree[c].Code, tree[c].Len); }
1996#endif
1997
1998#define d_code(dist) \
1999 ((dist) < 256 ? dist_code[dist] : dist_code[256+((dist)>>7)])
2000/* Mapping from a distance to a distance code. dist is the distance - 1 and
2001 * must not have side effects. dist_code[256] and dist_code[257] are never
2002 * used.
2003 */
2004
2005/* ===========================================================================
2006 * Output a short LSB first on the stream.
2007 * IN assertion: there is enough room in pendingBuf.
2008 */
2009#define put_short(s, w) { \
2010 put_byte(s, (uch)((w) & 0xff)); \
2011 put_byte(s, (uch)((ush)(w) >> 8)); \
2012}
2013
2014/* ===========================================================================
2015 * Send a value on a given number of bits.
2016 * IN assertion: length <= 16 and value fits in length bits.
2017 */
2018#ifdef DEBUG_ZLIB
2019local void send_bits OF((deflate_state *s, int value, int length));
2020
2021local void send_bits(s, value, length)
2022 deflate_state *s;
2023 int value; /* value to send */
2024 int length; /* number of bits */
2025{
2026 Tracevv((stderr," l %2d v %4x ", length, value));
2027 Assert(length > 0 && length <= 15, "invalid length");
2028 s->bits_sent += (ulg)length;
2029
2030 /* If not enough room in bi_buf, use (valid) bits from bi_buf and
2031 * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid))
2032 * unused bits in value.
2033 */
2034 if (s->bi_valid > (int)Buf_size - length) {
2035 s->bi_buf |= (value << s->bi_valid);
2036 put_short(s, s->bi_buf);
2037 s->bi_buf = (ush)value >> (Buf_size - s->bi_valid);
2038 s->bi_valid += length - Buf_size;
2039 } else {
2040 s->bi_buf |= value << s->bi_valid;
2041 s->bi_valid += length;
2042 }
2043}
2044#else /* !DEBUG_ZLIB */
2045
2046#define send_bits(s, value, length) \
2047{ int len = length;\
2048 if (s->bi_valid > (int)Buf_size - len) {\
2049 int val = value;\
2050 s->bi_buf |= (val << s->bi_valid);\
2051 put_short(s, s->bi_buf);\
2052 s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\
2053 s->bi_valid += len - Buf_size;\
2054 } else {\
2055 s->bi_buf |= (value) << s->bi_valid;\
2056 s->bi_valid += len;\
2057 }\
2058}
2059#endif /* DEBUG_ZLIB */
2060
2061
2062#define MAX(a,b) (a >= b ? a : b)
2063/* the arguments must not have side effects */
2064
2065/* ===========================================================================
2066 * Initialize the various 'constant' tables. In a multi-threaded environment,
2067 * this function may be called by two threads concurrently, but this is
2068 * harmless since both invocations do exactly the same thing.
2069 */
2070local void tr_static_init()
2071{
2072 static int static_init_done = 0;
2073 int n; /* iterates over tree elements */
2074 int bits; /* bit counter */
2075 int length; /* length value */
2076 int code; /* code value */
2077 int dist; /* distance index */
2078 ush bl_count[MAX_BITS+1];
2079 /* number of codes at each bit length for an optimal tree */
2080
2081 if (static_init_done) return;
2082
2083 /* Initialize the mapping length (0..255) -> length code (0..28) */
2084 length = 0;
2085 for (code = 0; code < LENGTH_CODES-1; code++) {
2086 base_length[code] = length;
2087 for (n = 0; n < (1<<extra_lbits[code]); n++) {
2088 length_code[length++] = (uch)code;
2089 }
2090 }
2091 Assert (length == 256, "tr_static_init: length != 256");
2092 /* Note that the length 255 (match length 258) can be represented
2093 * in two different ways: code 284 + 5 bits or code 285, so we
2094 * overwrite length_code[255] to use the best encoding:
2095 */
2096 length_code[length-1] = (uch)code;
2097
2098 /* Initialize the mapping dist (0..32K) -> dist code (0..29) */
2099 dist = 0;
2100 for (code = 0 ; code < 16; code++) {
2101 base_dist[code] = dist;
2102 for (n = 0; n < (1<<extra_dbits[code]); n++) {
2103 dist_code[dist++] = (uch)code;
2104 }
2105 }
2106 Assert (dist == 256, "tr_static_init: dist != 256");
2107 dist >>= 7; /* from now on, all distances are divided by 128 */
2108 for ( ; code < D_CODES; code++) {
2109 base_dist[code] = dist << 7;
2110 for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) {
2111 dist_code[256 + dist++] = (uch)code;
2112 }
2113 }
2114 Assert (dist == 256, "tr_static_init: 256+dist != 512");
2115
2116 /* Construct the codes of the static literal tree */
2117 for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
2118 n = 0;
2119 while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++;
2120 while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++;
2121 while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++;
2122 while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++;
2123 /* Codes 286 and 287 do not exist, but we must include them in the
2124 * tree construction to get a canonical Huffman tree (longest code
2125 * all ones)
2126 */
2127 gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count);
2128
2129 /* The static distance tree is trivial: */
2130 for (n = 0; n < D_CODES; n++) {
2131 static_dtree[n].Len = 5;
2132 static_dtree[n].Code = bi_reverse((unsigned)n, 5);
2133 }
2134 static_init_done = 1;
2135}
2136
2137/* ===========================================================================
2138 * Initialize the tree data structures for a new zlib stream.
2139 */
2140void _tr_init(s)
2141 deflate_state *s;
2142{
2143 tr_static_init();
2144
2145 s->compressed_len = 0L;
2146
2147 s->l_desc.dyn_tree = s->dyn_ltree;
2148 s->l_desc.stat_desc = &static_l_desc;
2149
2150 s->d_desc.dyn_tree = s->dyn_dtree;
2151 s->d_desc.stat_desc = &static_d_desc;
2152
2153 s->bl_desc.dyn_tree = s->bl_tree;
2154 s->bl_desc.stat_desc = &static_bl_desc;
2155
2156 s->bi_buf = 0;
2157 s->bi_valid = 0;
2158 s->last_eob_len = 8; /* enough lookahead for inflate */
2159#ifdef DEBUG_ZLIB
2160 s->bits_sent = 0L;
2161#endif
2162
2163 /* Initialize the first block of the first file: */
2164 init_block(s);
2165}
2166
2167/* ===========================================================================
2168 * Initialize a new block.
2169 */
2170local void init_block(s)
2171 deflate_state *s;
2172{
2173 int n; /* iterates over tree elements */
2174
2175 /* Initialize the trees. */
2176 for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0;
2177 for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0;
2178 for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0;
2179
2180 s->dyn_ltree[END_BLOCK].Freq = 1;
2181 s->opt_len = s->static_len = 0L;
2182 s->last_lit = s->matches = 0;
2183}
2184
2185#define SMALLEST 1
2186/* Index within the heap array of least frequent node in the Huffman tree */
2187
2188
2189/* ===========================================================================
2190 * Remove the smallest element from the heap and recreate the heap with
2191 * one less element. Updates heap and heap_len.
2192 */
2193#define pqremove(s, tree, top) \
2194{\
2195 top = s->heap[SMALLEST]; \
2196 s->heap[SMALLEST] = s->heap[s->heap_len--]; \
2197 pqdownheap(s, tree, SMALLEST); \
2198}
2199
2200/* ===========================================================================
2201 * Compares to subtrees, using the tree depth as tie breaker when
2202 * the subtrees have equal frequency. This minimizes the worst case length.
2203 */
2204#define smaller(tree, n, m, depth) \
2205 (tree[n].Freq < tree[m].Freq || \
2206 (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m]))
2207
2208/* ===========================================================================
2209 * Restore the heap property by moving down the tree starting at node k,
2210 * exchanging a node with the smallest of its two sons if necessary, stopping
2211 * when the heap property is re-established (each father smaller than its
2212 * two sons).
2213 */
2214local void pqdownheap(s, tree, k)
2215 deflate_state *s;
2216 ct_data *tree; /* the tree to restore */
2217 int k; /* node to move down */
2218{
2219 int v = s->heap[k];
2220 int j = k << 1; /* left son of k */
2221 while (j <= s->heap_len) {
2222 /* Set j to the smallest of the two sons: */
2223 if (j < s->heap_len &&
2224 smaller(tree, s->heap[j+1], s->heap[j], s->depth)) {
2225 j++;
2226 }
2227 /* Exit if v is smaller than both sons */
2228 if (smaller(tree, v, s->heap[j], s->depth)) break;
2229
2230 /* Exchange v with the smallest son */
2231 s->heap[k] = s->heap[j]; k = j;
2232
2233 /* And continue down the tree, setting j to the left son of k */
2234 j <<= 1;
2235 }
2236 s->heap[k] = v;
2237}
2238
2239/* ===========================================================================
2240 * Compute the optimal bit lengths for a tree and update the total bit length
2241 * for the current block.
2242 * IN assertion: the fields freq and dad are set, heap[heap_max] and
2243 * above are the tree nodes sorted by increasing frequency.
2244 * OUT assertions: the field len is set to the optimal bit length, the
2245 * array bl_count contains the frequencies for each bit length.
2246 * The length opt_len is updated; static_len is also updated if stree is
2247 * not null.
2248 */
2249local void gen_bitlen(s, desc)
2250 deflate_state *s;
2251 tree_desc *desc; /* the tree descriptor */
2252{
2253 ct_data *tree = desc->dyn_tree;
2254 int max_code = desc->max_code;
2255 ct_data *stree = desc->stat_desc->static_tree;
2256 intf *extra = desc->stat_desc->extra_bits;
2257 int base = desc->stat_desc->extra_base;
2258 int max_length = desc->stat_desc->max_length;
2259 int h; /* heap index */
2260 int n, m; /* iterate over the tree elements */
2261 int bits; /* bit length */
2262 int xbits; /* extra bits */
2263 ush f; /* frequency */
2264 int overflow = 0; /* number of elements with bit length too large */
2265
2266 for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0;
2267
2268 /* In a first pass, compute the optimal bit lengths (which may
2269 * overflow in the case of the bit length tree).
2270 */
2271 tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */
2272
2273 for (h = s->heap_max+1; h < HEAP_SIZE; h++) {
2274 n = s->heap[h];
2275 bits = tree[tree[n].Dad].Len + 1;
2276 if (bits > max_length) bits = max_length, overflow++;
2277 tree[n].Len = (ush)bits;
2278 /* We overwrite tree[n].Dad which is no longer needed */
2279
2280 if (n > max_code) continue; /* not a leaf node */
2281
2282 s->bl_count[bits]++;
2283 xbits = 0;
2284 if (n >= base) xbits = extra[n-base];
2285 f = tree[n].Freq;
2286 s->opt_len += (ulg)f * (bits + xbits);
2287 if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits);
2288 }
2289 if (overflow == 0) return;
2290
2291 Trace((stderr,"\nbit length overflow\n"));
2292 /* This happens for example on obj2 and pic of the Calgary corpus */
2293
2294 /* Find the first bit length which could increase: */
2295 do {
2296 bits = max_length-1;
2297 while (s->bl_count[bits] == 0) bits--;
2298 s->bl_count[bits]--; /* move one leaf down the tree */
2299 s->bl_count[bits+1] += 2; /* move one overflow item as its brother */
2300 s->bl_count[max_length]--;
2301 /* The brother of the overflow item also moves one step up,
2302 * but this does not affect bl_count[max_length]
2303 */
2304 overflow -= 2;
2305 } while (overflow > 0);
2306
2307 /* Now recompute all bit lengths, scanning in increasing frequency.
2308 * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
2309 * lengths instead of fixing only the wrong ones. This idea is taken
2310 * from 'ar' written by Haruhiko Okumura.)
2311 */
2312 for (bits = max_length; bits != 0; bits--) {
2313 n = s->bl_count[bits];
2314 while (n != 0) {
2315 m = s->heap[--h];
2316 if (m > max_code) continue;
2317 if (tree[m].Len != (unsigned) bits) {
2318 Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits));
2319 s->opt_len += ((long)bits - (long)tree[m].Len)
2320 *(long)tree[m].Freq;
2321 tree[m].Len = (ush)bits;
2322 }
2323 n--;
2324 }
2325 }
2326}
2327
2328/* ===========================================================================
2329 * Generate the codes for a given tree and bit counts (which need not be
2330 * optimal).
2331 * IN assertion: the array bl_count contains the bit length statistics for
2332 * the given tree and the field len is set for all tree elements.
2333 * OUT assertion: the field code is set for all tree elements of non
2334 * zero code length.
2335 */
2336local void gen_codes (tree, max_code, bl_count)
2337 ct_data *tree; /* the tree to decorate */
2338 int max_code; /* largest code with non zero frequency */
2339 ushf *bl_count; /* number of codes at each bit length */
2340{
2341 ush next_code[MAX_BITS+1]; /* next code value for each bit length */
2342 ush code = 0; /* running code value */
2343 int bits; /* bit index */
2344 int n; /* code index */
2345
2346 /* The distribution counts are first used to generate the code values
2347 * without bit reversal.
2348 */
2349 for (bits = 1; bits <= MAX_BITS; bits++) {
2350 next_code[bits] = code = (code + bl_count[bits-1]) << 1;
2351 }
2352 /* Check that the bit counts in bl_count are consistent. The last code
2353 * must be all ones.
2354 */
2355 Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1,
2356 "inconsistent bit counts");
2357 Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
2358
2359 for (n = 0; n <= max_code; n++) {
2360 int len = tree[n].Len;
2361 if (len == 0) continue;
2362 /* Now reverse the bits */
2363 tree[n].Code = bi_reverse(next_code[len]++, len);
2364
2365 Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
2366 n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1));
2367 }
2368}
2369
2370/* ===========================================================================
2371 * Construct one Huffman tree and assigns the code bit strings and lengths.
2372 * Update the total bit length for the current block.
2373 * IN assertion: the field freq is set for all tree elements.
2374 * OUT assertions: the fields len and code are set to the optimal bit length
2375 * and corresponding code. The length opt_len is updated; static_len is
2376 * also updated if stree is not null. The field max_code is set.
2377 */
2378local void build_tree(s, desc)
2379 deflate_state *s;
2380 tree_desc *desc; /* the tree descriptor */
2381{
2382 ct_data *tree = desc->dyn_tree;
2383 ct_data *stree = desc->stat_desc->static_tree;
2384 int elems = desc->stat_desc->elems;
2385 int n, m; /* iterate over heap elements */
2386 int max_code = -1; /* largest code with non zero frequency */
2387 int node; /* new node being created */
2388
2389 /* Construct the initial heap, with least frequent element in
2390 * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
2391 * heap[0] is not used.
2392 */
2393 s->heap_len = 0, s->heap_max = HEAP_SIZE;
2394
2395 for (n = 0; n < elems; n++) {
2396 if (tree[n].Freq != 0) {
2397 s->heap[++(s->heap_len)] = max_code = n;
2398 s->depth[n] = 0;
2399 } else {
2400 tree[n].Len = 0;
2401 }
2402 }
2403
2404 /* The pkzip format requires that at least one distance code exists,
2405 * and that at least one bit should be sent even if there is only one
2406 * possible code. So to avoid special checks later on we force at least
2407 * two codes of non zero frequency.
2408 */
2409 while (s->heap_len < 2) {
2410 node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0);
2411 tree[node].Freq = 1;
2412 s->depth[node] = 0;
2413 s->opt_len--; if (stree) s->static_len -= stree[node].Len;
2414 /* node is 0 or 1 so it does not have extra bits */
2415 }
2416 desc->max_code = max_code;
2417
2418 /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
2419 * establish sub-heaps of increasing lengths:
2420 */
2421 for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n);
2422
2423 /* Construct the Huffman tree by repeatedly combining the least two
2424 * frequent nodes.
2425 */
2426 node = elems; /* next internal node of the tree */
2427 do {
2428 pqremove(s, tree, n); /* n = node of least frequency */
2429 m = s->heap[SMALLEST]; /* m = node of next least frequency */
2430
2431 s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */
2432 s->heap[--(s->heap_max)] = m;
2433
2434 /* Create a new node father of n and m */
2435 tree[node].Freq = tree[n].Freq + tree[m].Freq;
2436 s->depth[node] = (uch) (MAX(s->depth[n], s->depth[m]) + 1);
2437 tree[n].Dad = tree[m].Dad = (ush)node;
2438#ifdef DUMP_BL_TREE
2439 if (tree == s->bl_tree) {
2440 fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)",
2441 node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq);
2442 }
2443#endif
2444 /* and insert the new node in the heap */
2445 s->heap[SMALLEST] = node++;
2446 pqdownheap(s, tree, SMALLEST);
2447
2448 } while (s->heap_len >= 2);
2449
2450 s->heap[--(s->heap_max)] = s->heap[SMALLEST];
2451
2452 /* At this point, the fields freq and dad are set. We can now
2453 * generate the bit lengths.
2454 */
2455 gen_bitlen(s, (tree_desc *)desc);
2456
2457 /* The field len is now set, we can generate the bit codes */
2458 gen_codes ((ct_data *)tree, max_code, s->bl_count);
2459}
2460
2461/* ===========================================================================
2462 * Scan a literal or distance tree to determine the frequencies of the codes
2463 * in the bit length tree.
2464 */
2465local void scan_tree (s, tree, max_code)
2466 deflate_state *s;
2467 ct_data *tree; /* the tree to be scanned */
2468 int max_code; /* and its largest code of non zero frequency */
2469{
2470 int n; /* iterates over all tree elements */
2471 int prevlen = -1; /* last emitted length */
2472 int curlen; /* length of current code */
2473 int nextlen = tree[0].Len; /* length of next code */
2474 int count = 0; /* repeat count of the current code */
2475 int max_count = 7; /* max repeat count */
2476 int min_count = 4; /* min repeat count */
2477
2478 if (nextlen == 0) max_count = 138, min_count = 3;
2479 tree[max_code+1].Len = (ush)0xffff; /* guard */
2480
2481 for (n = 0; n <= max_code; n++) {
2482 curlen = nextlen; nextlen = tree[n+1].Len;
2483 if (++count < max_count && curlen == nextlen) {
2484 continue;
2485 } else if (count < min_count) {
2486 s->bl_tree[curlen].Freq += count;
2487 } else if (curlen != 0) {
2488 if (curlen != prevlen) s->bl_tree[curlen].Freq++;
2489 s->bl_tree[REP_3_6].Freq++;
2490 } else if (count <= 10) {
2491 s->bl_tree[REPZ_3_10].Freq++;
2492 } else {
2493 s->bl_tree[REPZ_11_138].Freq++;
2494 }
2495 count = 0; prevlen = curlen;
2496 if (nextlen == 0) {
2497 max_count = 138, min_count = 3;
2498 } else if (curlen == nextlen) {
2499 max_count = 6, min_count = 3;
2500 } else {
2501 max_count = 7, min_count = 4;
2502 }
2503 }
2504}
2505
2506/* ===========================================================================
2507 * Send a literal or distance tree in compressed form, using the codes in
2508 * bl_tree.
2509 */
2510local void send_tree (s, tree, max_code)
2511 deflate_state *s;
2512 ct_data *tree; /* the tree to be scanned */
2513 int max_code; /* and its largest code of non zero frequency */
2514{
2515 int n; /* iterates over all tree elements */
2516 int prevlen = -1; /* last emitted length */
2517 int curlen; /* length of current code */
2518 int nextlen = tree[0].Len; /* length of next code */
2519 int count = 0; /* repeat count of the current code */
2520 int max_count = 7; /* max repeat count */
2521 int min_count = 4; /* min repeat count */
2522
2523 /* tree[max_code+1].Len = -1; */ /* guard already set */
2524 if (nextlen == 0) max_count = 138, min_count = 3;
2525
2526 for (n = 0; n <= max_code; n++) {
2527 curlen = nextlen; nextlen = tree[n+1].Len;
2528 if (++count < max_count && curlen == nextlen) {
2529 continue;
2530 } else if (count < min_count) {
2531 do { send_code(s, curlen, s->bl_tree); } while (--count != 0);
2532
2533 } else if (curlen != 0) {
2534 if (curlen != prevlen) {
2535 send_code(s, curlen, s->bl_tree); count--;
2536 }
2537 Assert(count >= 3 && count <= 6, " 3_6?");
2538 send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2);
2539
2540 } else if (count <= 10) {
2541 send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3);
2542
2543 } else {
2544 send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7);
2545 }
2546 count = 0; prevlen = curlen;
2547 if (nextlen == 0) {
2548 max_count = 138, min_count = 3;
2549 } else if (curlen == nextlen) {
2550 max_count = 6, min_count = 3;
2551 } else {
2552 max_count = 7, min_count = 4;
2553 }
2554 }
2555}
2556
2557/* ===========================================================================
2558 * Construct the Huffman tree for the bit lengths and return the index in
2559 * bl_order of the last bit length code to send.
2560 */
2561local int build_bl_tree(s)
2562 deflate_state *s;
2563{
2564 int max_blindex; /* index of last bit length code of non zero freq */
2565
2566 /* Determine the bit length frequencies for literal and distance trees */
2567 scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code);
2568 scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code);
2569
2570 /* Build the bit length tree: */
2571 build_tree(s, (tree_desc *)(&(s->bl_desc)));
2572 /* opt_len now includes the length of the tree representations, except
2573 * the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
2574 */
2575
2576 /* Determine the number of bit length codes to send. The pkzip format
2577 * requires that at least 4 bit length codes be sent. (appnote.txt says
2578 * 3 but the actual value used is 4.)
2579 */
2580 for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) {
2581 if (s->bl_tree[bl_order[max_blindex]].Len != 0) break;
2582 }
2583 /* Update opt_len to include the bit length tree and counts */
2584 s->opt_len += 3*(max_blindex+1) + 5+5+4;
2585 Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld",
2586 s->opt_len, s->static_len));
2587
2588 return max_blindex;
2589}
2590
2591/* ===========================================================================
2592 * Send the header for a block using dynamic Huffman trees: the counts, the
2593 * lengths of the bit length codes, the literal tree and the distance tree.
2594 * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
2595 */
2596local void send_all_trees(s, lcodes, dcodes, blcodes)
2597 deflate_state *s;
2598 int lcodes, dcodes, blcodes; /* number of codes for each tree */
2599{
2600 int rank; /* index in bl_order */
2601
2602 Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
2603 Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
2604 "too many codes");
2605 Tracev((stderr, "\nbl counts: "));
2606 send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */
2607 send_bits(s, dcodes-1, 5);
2608 send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */
2609 for (rank = 0; rank < blcodes; rank++) {
2610 Tracev((stderr, "\nbl code %2d ", bl_order[rank]));
2611 send_bits(s, s->bl_tree[bl_order[rank]].Len, 3);
2612 }
2613 Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent));
2614
2615 send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */
2616 Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent));
2617
2618 send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */
2619 Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent));
2620}
2621
2622/* ===========================================================================
2623 * Send a stored block
2624 */
2625void _tr_stored_block(s, buf, stored_len, eof)
2626 deflate_state *s;
2627 charf *buf; /* input block */
2628 ulg stored_len; /* length of input block */
2629 int eof; /* true if this is the last block for a file */
2630{
2631 send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */
2632 s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L;
2633 s->compressed_len += (stored_len + 4) << 3;
2634
2635 copy_block(s, buf, (unsigned)stored_len, 1); /* with header */
2636}
2637
2638/* Send just the `stored block' type code without any length bytes or data.
2639 */
2640void _tr_stored_type_only(s)
2641 deflate_state *s;
2642{
2643 send_bits(s, (STORED_BLOCK << 1), 3);
2644 bi_windup(s);
2645 s->compressed_len = (s->compressed_len + 3) & ~7L;
2646}
2647
2648
2649/* ===========================================================================
2650 * Send one empty static block to give enough lookahead for inflate.
2651 * This takes 10 bits, of which 7 may remain in the bit buffer.
2652 * The current inflate code requires 9 bits of lookahead. If the
2653 * last two codes for the previous block (real code plus EOB) were coded
2654 * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode
2655 * the last real code. In this case we send two empty static blocks instead
2656 * of one. (There are no problems if the previous block is stored or fixed.)
2657 * To simplify the code, we assume the worst case of last real code encoded
2658 * on one bit only.
2659 */
2660void _tr_align(s)
2661 deflate_state *s;
2662{
2663 send_bits(s, STATIC_TREES<<1, 3);
2664 send_code(s, END_BLOCK, static_ltree);
2665 s->compressed_len += 10L; /* 3 for block type, 7 for EOB */
2666 bi_flush(s);
2667 /* Of the 10 bits for the empty block, we have already sent
2668 * (10 - bi_valid) bits. The lookahead for the last real code (before
2669 * the EOB of the previous block) was thus at least one plus the length
2670 * of the EOB plus what we have just sent of the empty static block.
2671 */
2672 if (1 + s->last_eob_len + 10 - s->bi_valid < 9) {
2673 send_bits(s, STATIC_TREES<<1, 3);
2674 send_code(s, END_BLOCK, static_ltree);
2675 s->compressed_len += 10L;
2676 bi_flush(s);
2677 }
2678 s->last_eob_len = 7;
2679}
2680
2681/* ===========================================================================
2682 * Determine the best encoding for the current block: dynamic trees, static
2683 * trees or store, and output the encoded block to the zip file. This function
2684 * returns the total compressed length for the file so far.
2685 */
2686ulg _tr_flush_block(s, buf, stored_len, eof)
2687 deflate_state *s;
2688 charf *buf; /* input block, or NULL if too old */
2689 ulg stored_len; /* length of input block */
2690 int eof; /* true if this is the last block for a file */
2691{
2692 ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
2693 int max_blindex = 0; /* index of last bit length code of non zero freq */
2694
2695 /* Build the Huffman trees unless a stored block is forced */
2696 if (s->level > 0) {
2697
2698 /* Check if the file is ascii or binary */
2699 if (s->data_type == Z_UNKNOWN) set_data_type(s);
2700
2701 /* Construct the literal and distance trees */
2702 build_tree(s, (tree_desc *)(&(s->l_desc)));
2703 Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len,
2704 s->static_len));
2705
2706 build_tree(s, (tree_desc *)(&(s->d_desc)));
2707 Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len,
2708 s->static_len));
2709 /* At this point, opt_len and static_len are the total bit lengths of
2710 * the compressed block data, excluding the tree representations.
2711 */
2712
2713 /* Build the bit length tree for the above two trees, and get the index
2714 * in bl_order of the last bit length code to send.
2715 */
2716 max_blindex = build_bl_tree(s);
2717
2718 /* Determine the best encoding. Compute first the block length in bytes*/
2719 opt_lenb = (s->opt_len+3+7)>>3;
2720 static_lenb = (s->static_len+3+7)>>3;
2721
2722 Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
2723 opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
2724 s->last_lit));
2725
2726 if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
2727
2728 } else {
2729 Assert(buf != (char*)0, "lost buf");
2730 opt_lenb = static_lenb = stored_len + 5; /* force a stored block */
2731 }
2732
2733 /* If compression failed and this is the first and last block,
2734 * and if the .zip file can be seeked (to rewrite the local header),
2735 * the whole file is transformed into a stored file:
2736 */
2737#ifdef STORED_FILE_OK
2738# ifdef FORCE_STORED_FILE
2739 if (eof && s->compressed_len == 0L) { /* force stored file */
2740# else
2741 if (stored_len <= opt_lenb && eof && s->compressed_len==0L && seekable()) {
2742# endif
2743 /* Since LIT_BUFSIZE <= 2*WSIZE, the input data must be there: */
2744 if (buf == (charf*)0) error ("block vanished");
2745
2746 copy_block(s, buf, (unsigned)stored_len, 0); /* without header */
2747 s->compressed_len = stored_len << 3;
2748 s->method = STORED;
2749 } else
2750#endif /* STORED_FILE_OK */
2751
2752#ifdef FORCE_STORED
2753 if (buf != (char*)0) { /* force stored block */
2754#else
2755 if (stored_len+4 <= opt_lenb && buf != (char*)0) {
2756 /* 4: two words for the lengths */
2757#endif
2758 /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
2759 * Otherwise we can't have processed more than WSIZE input bytes since
2760 * the last block flush, because compression would have been
2761 * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
2762 * transform a block into a stored block.
2763 */
2764 _tr_stored_block(s, buf, stored_len, eof);
2765
2766#ifdef FORCE_STATIC
2767 } else if (static_lenb >= 0) { /* force static trees */
2768#else
2769 } else if (static_lenb == opt_lenb) {
2770#endif
2771 send_bits(s, (STATIC_TREES<<1)+eof, 3);
2772 compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree);
2773 s->compressed_len += 3 + s->static_len;
2774 } else {
2775 send_bits(s, (DYN_TREES<<1)+eof, 3);
2776 send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1,
2777 max_blindex+1);
2778 compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree);
2779 s->compressed_len += 3 + s->opt_len;
2780 }
2781 Assert (s->compressed_len == s->bits_sent, "bad compressed size");
2782 init_block(s);
2783
2784 if (eof) {
2785 bi_windup(s);
2786 s->compressed_len += 7; /* align on byte boundary */
2787 }
2788 Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3,
2789 s->compressed_len-7*eof));
2790
2791 return s->compressed_len >> 3;
2792}
2793
2794/* ===========================================================================
2795 * Save the match info and tally the frequency counts. Return true if
2796 * the current block must be flushed.
2797 */
2798int _tr_tally (s, dist, lc)
2799 deflate_state *s;
2800 unsigned dist; /* distance of matched string */
2801 unsigned lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */
2802{
2803 s->d_buf[s->last_lit] = (ush)dist;
2804 s->l_buf[s->last_lit++] = (uch)lc;
2805 if (dist == 0) {
2806 /* lc is the unmatched char */
2807 s->dyn_ltree[lc].Freq++;
2808 } else {
2809 s->matches++;
2810 /* Here, lc is the match length - MIN_MATCH */
2811 dist--; /* dist = match distance - 1 */
2812 Assert((ush)dist < (ush)MAX_DIST(s) &&
2813 (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
2814 (ush)d_code(dist) < (ush)D_CODES, "_tr_tally: bad match");
2815
2816 s->dyn_ltree[length_code[lc]+LITERALS+1].Freq++;
2817 s->dyn_dtree[d_code(dist)].Freq++;
2818 }
2819
2820 /* Try to guess if it is profitable to stop the current block here */
2821 if (s->level > 2 && (s->last_lit & 0xfff) == 0) {
2822 /* Compute an upper bound for the compressed length */
2823 ulg out_length = (ulg)s->last_lit*8L;
2824 ulg in_length = (ulg)((long)s->strstart - s->block_start);
2825 int dcode;
2826 for (dcode = 0; dcode < D_CODES; dcode++) {
2827 out_length += (ulg)s->dyn_dtree[dcode].Freq *
2828 (5L+extra_dbits[dcode]);
2829 }
2830 out_length >>= 3;
2831 Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ",
2832 s->last_lit, in_length, out_length,
2833 100L - out_length*100L/in_length));
2834 if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1;
2835 }
2836 return (s->last_lit == s->lit_bufsize-1);
2837 /* We avoid equality with lit_bufsize because of wraparound at 64K
2838 * on 16 bit machines and because stored blocks are restricted to
2839 * 64K-1 bytes.
2840 */
2841}
2842
2843/* ===========================================================================
2844 * Send the block data compressed using the given Huffman trees
2845 */
2846local void compress_block(s, ltree, dtree)
2847 deflate_state *s;
2848 ct_data *ltree; /* literal tree */
2849 ct_data *dtree; /* distance tree */
2850{
2851 unsigned dist; /* distance of matched string */
2852 int lc; /* match length or unmatched char (if dist == 0) */
2853 unsigned lx = 0; /* running index in l_buf */
2854 unsigned code; /* the code to send */
2855 int extra; /* number of extra bits to send */
2856
2857 if (s->last_lit != 0) do {
2858 dist = s->d_buf[lx];
2859 lc = s->l_buf[lx++];
2860 if (dist == 0) {
2861 send_code(s, lc, ltree); /* send a literal byte */
2862 Tracecv(isgraph(lc), (stderr," '%c' ", lc));
2863 } else {
2864 /* Here, lc is the match length - MIN_MATCH */
2865 code = length_code[lc];
2866 send_code(s, code+LITERALS+1, ltree); /* send the length code */
2867 extra = extra_lbits[code];
2868 if (extra != 0) {
2869 lc -= base_length[code];
2870 send_bits(s, lc, extra); /* send the extra length bits */
2871 }
2872 dist--; /* dist is now the match distance - 1 */
2873 code = d_code(dist);
2874 Assert (code < D_CODES, "bad d_code");
2875
2876 send_code(s, code, dtree); /* send the distance code */
2877 extra = extra_dbits[code];
2878 if (extra != 0) {
2879 dist -= base_dist[code];
2880 send_bits(s, dist, extra); /* send the extra distance bits */
2881 }
2882 } /* literal or match pair ? */
2883
2884 /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */
2885 Assert(s->pending < s->lit_bufsize + 2*lx, "pendingBuf overflow");
2886
2887 } while (lx < s->last_lit);
2888
2889 send_code(s, END_BLOCK, ltree);
2890 s->last_eob_len = ltree[END_BLOCK].Len;
2891}
2892
2893/* ===========================================================================
2894 * Set the data type to ASCII or BINARY, using a crude approximation:
2895 * binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise.
2896 * IN assertion: the fields freq of dyn_ltree are set and the total of all
2897 * frequencies does not exceed 64K (to fit in an int on 16 bit machines).
2898 */
2899local void set_data_type(s)
2900 deflate_state *s;
2901{
2902 int n = 0;
2903 unsigned ascii_freq = 0;
2904 unsigned bin_freq = 0;
2905 while (n < 7) bin_freq += s->dyn_ltree[n++].Freq;
2906 while (n < 128) ascii_freq += s->dyn_ltree[n++].Freq;
2907 while (n < LITERALS) bin_freq += s->dyn_ltree[n++].Freq;
2908 s->data_type = (Byte)(bin_freq > (ascii_freq >> 2) ? Z_BINARY : Z_ASCII);
2909}
2910
2911/* ===========================================================================
2912 * Reverse the first len bits of a code, using straightforward code (a faster
2913 * method would use a table)
2914 * IN assertion: 1 <= len <= 15
2915 */
2916local unsigned bi_reverse(code, len)
2917 unsigned code; /* the value to invert */
2918 int len; /* its bit length */
2919{
2920 register unsigned res = 0;
2921 do {
2922 res |= code & 1;
2923 code >>= 1, res <<= 1;
2924 } while (--len > 0);
2925 return res >> 1;
2926}
2927
2928/* ===========================================================================
2929 * Flush the bit buffer, keeping at most 7 bits in it.
2930 */
2931local void bi_flush(s)
2932 deflate_state *s;
2933{
2934 if (s->bi_valid == 16) {
2935 put_short(s, s->bi_buf);
2936 s->bi_buf = 0;
2937 s->bi_valid = 0;
2938 } else if (s->bi_valid >= 8) {
2939 put_byte(s, (Byte)s->bi_buf);
2940 s->bi_buf >>= 8;
2941 s->bi_valid -= 8;
2942 }
2943}
2944
2945/* ===========================================================================
2946 * Flush the bit buffer and align the output on a byte boundary
2947 */
2948local void bi_windup(s)
2949 deflate_state *s;
2950{
2951 if (s->bi_valid > 8) {
2952 put_short(s, s->bi_buf);
2953 } else if (s->bi_valid > 0) {
2954 put_byte(s, (Byte)s->bi_buf);
2955 }
2956 s->bi_buf = 0;
2957 s->bi_valid = 0;
2958#ifdef DEBUG_ZLIB
2959 s->bits_sent = (s->bits_sent+7) & ~7;
2960#endif
2961}
2962
2963/* ===========================================================================
2964 * Copy a stored block, storing first the length and its
2965 * one's complement if requested.
2966 */
2967local void copy_block(s, buf, len, header)
2968 deflate_state *s;
2969 charf *buf; /* the input data */
2970 unsigned len; /* its length */
2971 int header; /* true if block header must be written */
2972{
2973 bi_windup(s); /* align on byte boundary */
2974 s->last_eob_len = 8; /* enough lookahead for inflate */
2975
2976 if (header) {
2977 put_short(s, (ush)len);
2978 put_short(s, (ush)~len);
2979#ifdef DEBUG_ZLIB
2980 s->bits_sent += 2*16;
2981#endif
2982 }
2983#ifdef DEBUG_ZLIB
2984 s->bits_sent += (ulg)len<<3;
2985#endif
2986 /* bundle up the put_byte(s, *buf++) calls */
2987 zmemcpy(&s->pending_buf[s->pending], buf, len);
2988 s->pending += len;
2989}
2990/* --- trees.c */
2991
2992/* +++ inflate.c */
2993/* inflate.c -- zlib interface to inflate modules
2994 * Copyright (C) 1995-1996 Mark Adler
2995 * For conditions of distribution and use, see copyright notice in zlib.h
2996 */
2997
2998/* #include "zutil.h" */
2999
3000/* +++ infblock.h */
3001/* infblock.h -- header to use infblock.c
3002 * Copyright (C) 1995-1996 Mark Adler
3003 * For conditions of distribution and use, see copyright notice in zlib.h
3004 */
3005
3006/* WARNING: this file should *not* be used by applications. It is
3007 part of the implementation of the compression library and is
3008 subject to change. Applications should only use zlib.h.
3009 */
3010
3011struct inflate_blocks_state;
3012typedef struct inflate_blocks_state FAR inflate_blocks_statef;
3013
3014extern inflate_blocks_statef * inflate_blocks_new OF((
3015 z_streamp z,
3016 check_func c, /* check function */
3017 uInt w)); /* window size */
3018
3019extern int inflate_blocks OF((
3020 inflate_blocks_statef *,
3021 z_streamp ,
3022 int)); /* initial return code */
3023
3024extern void inflate_blocks_reset OF((
3025 inflate_blocks_statef *,
3026 z_streamp ,
3027 uLongf *)); /* check value on output */
3028
3029extern int inflate_blocks_free OF((
3030 inflate_blocks_statef *,
3031 z_streamp ,
3032 uLongf *)); /* check value on output */
3033
3034extern void inflate_set_dictionary OF((
3035 inflate_blocks_statef *s,
3036 const Bytef *d, /* dictionary */
3037 uInt n)); /* dictionary length */
3038
3039extern int inflate_addhistory OF((
3040 inflate_blocks_statef *,
3041 z_streamp));
3042
3043extern int inflate_packet_flush OF((
3044 inflate_blocks_statef *));
3045/* --- infblock.h */
3046
3047#ifndef NO_DUMMY_DECL
3048struct inflate_blocks_state {int dummy;}; /* for buggy compilers */
3049#endif
3050
3051/* inflate private state */
3052struct internal_state {
3053
3054 /* mode */
3055 enum {
3056 METHOD, /* waiting for method byte */
3057 FLAG, /* waiting for flag byte */
3058 DICT4, /* four dictionary check bytes to go */
3059 DICT3, /* three dictionary check bytes to go */
3060 DICT2, /* two dictionary check bytes to go */
3061 DICT1, /* one dictionary check byte to go */
3062 DICT0, /* waiting for inflateSetDictionary */
3063 BLOCKS, /* decompressing blocks */
3064 CHECK4, /* four check bytes to go */
3065 CHECK3, /* three check bytes to go */
3066 CHECK2, /* two check bytes to go */
3067 CHECK1, /* one check byte to go */
3068 DONE, /* finished check, done */
3069 BAD} /* got an error--stay here */
3070 mode; /* current inflate mode */
3071
3072 /* mode dependent information */
3073 union {
3074 uInt method; /* if FLAGS, method byte */
3075 struct {
3076 uLong was; /* computed check value */
3077 uLong need; /* stream check value */
3078 } check; /* if CHECK, check values to compare */
3079 uInt marker; /* if BAD, inflateSync's marker bytes count */
3080 } sub; /* submode */
3081
3082 /* mode independent information */
3083 int nowrap; /* flag for no wrapper */
3084 uInt wbits; /* log2(window size) (8..15, defaults to 15) */
3085 inflate_blocks_statef
3086 *blocks; /* current inflate_blocks state */
3087
3088};
3089
3090
3091int inflateReset(z)
3092z_streamp z;
3093{
3094 uLong c;
3095
3096 if (z == Z_NULL || z->state == Z_NULL)
3097 return Z_STREAM_ERROR;
3098 z->total_in = z->total_out = 0;
3099 z->msg = Z_NULL;
3100 z->state->mode = z->state->nowrap ? BLOCKS : METHOD;
3101 inflate_blocks_reset(z->state->blocks, z, &c);
3102 Trace((stderr, "inflate: reset\n"));
3103 return Z_OK;
3104}
3105
3106
3107int inflateEnd(z)
3108z_streamp z;
3109{
3110 uLong c;
3111
3112 if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL)
3113 return Z_STREAM_ERROR;
3114 if (z->state->blocks != Z_NULL)
3115 inflate_blocks_free(z->state->blocks, z, &c);
3116 ZFREE(z, z->state);
3117 z->state = Z_NULL;
3118 Trace((stderr, "inflate: end\n"));
3119 return Z_OK;
3120}
3121
3122
3123int inflateInit2_(z, w, version, stream_size)
3124z_streamp z;
3125int w;
3126const char *version;
3127int stream_size;
3128{
3129 if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
3130 stream_size != sizeof(z_stream))
3131 return Z_VERSION_ERROR;
3132
3133 /* initialize state */
3134 if (z == Z_NULL)
3135 return Z_STREAM_ERROR;
3136 z->msg = Z_NULL;
3137#ifndef NO_ZCFUNCS
3138 if (z->zalloc == Z_NULL)
3139 {
3140 z->zalloc = zcalloc;
3141 z->opaque = (voidpf)0;
3142 }
3143 if (z->zfree == Z_NULL) z->zfree = zcfree;
3144#endif
3145 if ((z->state = (struct internal_state FAR *)
3146 ZALLOC(z,1,sizeof(struct internal_state))) == Z_NULL)
3147 return Z_MEM_ERROR;
3148 z->state->blocks = Z_NULL;
3149
3150 /* handle undocumented nowrap option (no zlib header or check) */
3151 z->state->nowrap = 0;
3152 if (w < 0)
3153 {
3154 w = - w;
3155 z->state->nowrap = 1;
3156 }
3157
3158 /* set window size */
3159 if (w < 8 || w > 15)
3160 {
3161 inflateEnd(z);
3162 return Z_STREAM_ERROR;
3163 }
3164 z->state->wbits = (uInt)w;
3165
3166 /* create inflate_blocks state */
3167 if ((z->state->blocks =
3168 inflate_blocks_new(z, z->state->nowrap ? Z_NULL : adler32, (uInt)1 << w))
3169 == Z_NULL)
3170 {
3171 inflateEnd(z);
3172 return Z_MEM_ERROR;
3173 }
3174 Trace((stderr, "inflate: allocated\n"));
3175
3176 /* reset state */
3177 inflateReset(z);
3178 return Z_OK;
3179}
3180
3181
3182int inflateInit_(z, version, stream_size)
3183z_streamp z;
3184const char *version;
3185int stream_size;
3186{
3187 return inflateInit2_(z, DEF_WBITS, version, stream_size);
3188}
3189
3190
3191#define NEEDBYTE {if(z->avail_in==0)goto empty;r=Z_OK;}
3192#define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++)
3193
3194int inflate(z, f)
3195z_streamp z;
3196int f;
3197{
3198 int r;
3199 uInt b;
3200
3201 if (z == Z_NULL || z->state == Z_NULL || z->next_in == Z_NULL || f < 0)
3202 return Z_STREAM_ERROR;
3203 r = Z_BUF_ERROR;
3204 while (1) switch (z->state->mode)
3205 {
3206 case METHOD:
3207 NEEDBYTE
3208 if (((z->state->sub.method = NEXTBYTE) & 0xf) != Z_DEFLATED)
3209 {
3210 z->state->mode = BAD;
3211 z->msg = (char*)"unknown compression method";
3212 z->state->sub.marker = 5; /* can't try inflateSync */
3213 break;
3214 }
3215 if ((z->state->sub.method >> 4) + 8 > z->state->wbits)
3216 {
3217 z->state->mode = BAD;
3218 z->msg = (char*)"invalid window size";
3219 z->state->sub.marker = 5; /* can't try inflateSync */
3220 break;
3221 }
3222 z->state->mode = FLAG;
3223 case FLAG:
3224 NEEDBYTE
3225 b = NEXTBYTE;
3226 if (((z->state->sub.method << 8) + b) % 31)
3227 {
3228 z->state->mode = BAD;
3229 z->msg = (char*)"incorrect header check";
3230 z->state->sub.marker = 5; /* can't try inflateSync */
3231 break;
3232 }
3233 Trace((stderr, "inflate: zlib header ok\n"));
3234 if (!(b & PRESET_DICT))
3235 {
3236 z->state->mode = BLOCKS;
3237 break;
3238 }
3239 z->state->mode = DICT4;
3240 case DICT4:
3241 NEEDBYTE
3242 z->state->sub.check.need = (uLong)NEXTBYTE << 24;
3243 z->state->mode = DICT3;
3244 case DICT3:
3245 NEEDBYTE
3246 z->state->sub.check.need += (uLong)NEXTBYTE << 16;
3247 z->state->mode = DICT2;
3248 case DICT2:
3249 NEEDBYTE
3250 z->state->sub.check.need += (uLong)NEXTBYTE << 8;
3251 z->state->mode = DICT1;
3252 case DICT1:
3253 NEEDBYTE
3254 z->state->sub.check.need += (uLong)NEXTBYTE;
3255 z->adler = z->state->sub.check.need;
3256 z->state->mode = DICT0;
3257 return Z_NEED_DICT;
3258 case DICT0:
3259 z->state->mode = BAD;
3260 z->msg = (char*)"need dictionary";
3261 z->state->sub.marker = 0; /* can try inflateSync */
3262 return Z_STREAM_ERROR;
3263 case BLOCKS:
3264 r = inflate_blocks(z->state->blocks, z, r);
3265 if (f == Z_PACKET_FLUSH && z->avail_in == 0 && z->avail_out != 0)
3266 r = inflate_packet_flush(z->state->blocks);
3267 if (r == Z_DATA_ERROR)
3268 {
3269 z->state->mode = BAD;
3270 z->state->sub.marker = 0; /* can try inflateSync */
3271 break;
3272 }
3273 if (r != Z_STREAM_END)
3274 return r;
3275 r = Z_OK;
3276 inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was);
3277 if (z->state->nowrap)
3278 {
3279 z->state->mode = DONE;
3280 break;
3281 }
3282 z->state->mode = CHECK4;
3283 case CHECK4:
3284 NEEDBYTE
3285 z->state->sub.check.need = (uLong)NEXTBYTE << 24;
3286 z->state->mode = CHECK3;
3287 case CHECK3:
3288 NEEDBYTE
3289 z->state->sub.check.need += (uLong)NEXTBYTE << 16;
3290 z->state->mode = CHECK2;
3291 case CHECK2:
3292 NEEDBYTE
3293 z->state->sub.check.need += (uLong)NEXTBYTE << 8;
3294 z->state->mode = CHECK1;
3295 case CHECK1:
3296 NEEDBYTE
3297 z->state->sub.check.need += (uLong)NEXTBYTE;
3298
3299 if (z->state->sub.check.was != z->state->sub.check.need)
3300 {
3301 z->state->mode = BAD;
3302 z->msg = (char*)"incorrect data check";
3303 z->state->sub.marker = 5; /* can't try inflateSync */
3304 break;
3305 }
3306 Trace((stderr, "inflate: zlib check ok\n"));
3307 z->state->mode = DONE;
3308 case DONE:
3309 return Z_STREAM_END;
3310 case BAD:
3311 return Z_DATA_ERROR;
3312 default:
3313 return Z_STREAM_ERROR;
3314 }
3315
3316 empty:
3317 if (f != Z_PACKET_FLUSH)
3318 return r;
3319 z->state->mode = BAD;
3320 z->msg = (char *)"need more for packet flush";
3321 z->state->sub.marker = 0; /* can try inflateSync */
3322 return Z_DATA_ERROR;
3323}
3324
3325
3326int inflateSetDictionary(z, dictionary, dictLength)
3327z_streamp z;
3328const Bytef *dictionary;
3329uInt dictLength;
3330{
3331 uInt length = dictLength;
3332
3333 if (z == Z_NULL || z->state == Z_NULL || z->state->mode != DICT0)
3334 return Z_STREAM_ERROR;
3335
3336 if (adler32(1L, dictionary, dictLength) != z->adler) return Z_DATA_ERROR;
3337 z->adler = 1L;
3338
3339 if (length >= ((uInt)1<<z->state->wbits))
3340 {
3341 length = (1<<z->state->wbits)-1;
3342 dictionary += dictLength - length;
3343 }
3344 inflate_set_dictionary(z->state->blocks, dictionary, length);
3345 z->state->mode = BLOCKS;
3346 return Z_OK;
3347}
3348
3349/*
3350 * This subroutine adds the data at next_in/avail_in to the output history
3351 * without performing any output. The output buffer must be "caught up";
3352 * i.e. no pending output (hence s->read equals s->write), and the state must
3353 * be BLOCKS (i.e. we should be willing to see the start of a series of
3354 * BLOCKS). On exit, the output will also be caught up, and the checksum
3355 * will have been updated if need be.
3356 */
3357
3358int inflateIncomp(z)
3359z_stream *z;
3360{
3361 if (z->state->mode != BLOCKS)
3362 return Z_DATA_ERROR;
3363 return inflate_addhistory(z->state->blocks, z);
3364}
3365
3366
3367int inflateSync(z)
3368z_streamp z;
3369{
3370 uInt n; /* number of bytes to look at */
3371 Bytef *p; /* pointer to bytes */
3372 uInt m; /* number of marker bytes found in a row */
3373 uLong r, w; /* temporaries to save total_in and total_out */
3374
3375 /* set up */
3376 if (z == Z_NULL || z->state == Z_NULL)
3377 return Z_STREAM_ERROR;
3378 if (z->state->mode != BAD)
3379 {
3380 z->state->mode = BAD;
3381 z->state->sub.marker = 0;
3382 }
3383 if ((n = z->avail_in) == 0)
3384 return Z_BUF_ERROR;
3385 p = z->next_in;
3386 m = z->state->sub.marker;
3387
3388 /* search */
3389 while (n && m < 4)
3390 {
3391 if (*p == (Byte)(m < 2 ? 0 : 0xff))
3392 m++;
3393 else if (*p)
3394 m = 0;
3395 else
3396 m = 4 - m;
3397 p++, n--;
3398 }
3399
3400 /* restore */
3401 z->total_in += p - z->next_in;
3402 z->next_in = p;
3403 z->avail_in = n;
3404 z->state->sub.marker = m;
3405
3406 /* return no joy or set up to restart on a new block */
3407 if (m != 4)
3408 return Z_DATA_ERROR;
3409 r = z->total_in; w = z->total_out;
3410 inflateReset(z);
3411 z->total_in = r; z->total_out = w;
3412 z->state->mode = BLOCKS;
3413 return Z_OK;
3414}
3415
3416#undef NEEDBYTE
3417#undef NEXTBYTE
3418/* --- inflate.c */
3419
3420/* +++ infblock.c */
3421/* infblock.c -- interpret and process block types to last block
3422 * Copyright (C) 1995-1996 Mark Adler
3423 * For conditions of distribution and use, see copyright notice in zlib.h
3424 */
3425
3426/* #include "zutil.h" */
3427/* #include "infblock.h" */
3428
3429/* +++ inftrees.h */
3430/* inftrees.h -- header to use inftrees.c
3431 * Copyright (C) 1995-1996 Mark Adler
3432 * For conditions of distribution and use, see copyright notice in zlib.h
3433 */
3434
3435/* WARNING: this file should *not* be used by applications. It is
3436 part of the implementation of the compression library and is
3437 subject to change. Applications should only use zlib.h.
3438 */
3439
3440/* Huffman code lookup table entry--this entry is four bytes for machines
3441 that have 16-bit pointers (e.g. PC's in the small or medium model). */
3442
3443typedef struct inflate_huft_s FAR inflate_huft;
3444
3445struct inflate_huft_s {
3446 union {
3447 struct {
3448 Byte Exop; /* number of extra bits or operation */
3449 Byte Bits; /* number of bits in this code or subcode */
3450 } what;
3451 Bytef *pad; /* pad structure to a power of 2 (4 bytes for */
3452 } word; /* 16-bit, 8 bytes for 32-bit machines) */
3453 union {
3454 uInt Base; /* literal, length base, or distance base */
3455 inflate_huft *Next; /* pointer to next level of table */
3456 } more;
3457};
3458
3459#ifdef DEBUG_ZLIB
3460 extern uInt inflate_hufts;
3461#endif
3462
3463extern int inflate_trees_bits OF((
3464 uIntf *, /* 19 code lengths */
3465 uIntf *, /* bits tree desired/actual depth */
3466 inflate_huft * FAR *, /* bits tree result */
3467 z_streamp )); /* for zalloc, zfree functions */
3468
3469extern int inflate_trees_dynamic OF((
3470 uInt, /* number of literal/length codes */
3471 uInt, /* number of distance codes */
3472 uIntf *, /* that many (total) code lengths */
3473 uIntf *, /* literal desired/actual bit depth */
3474 uIntf *, /* distance desired/actual bit depth */
3475 inflate_huft * FAR *, /* literal/length tree result */
3476 inflate_huft * FAR *, /* distance tree result */
3477 z_streamp )); /* for zalloc, zfree functions */
3478
3479extern int inflate_trees_fixed OF((
3480 uIntf *, /* literal desired/actual bit depth */
3481 uIntf *, /* distance desired/actual bit depth */
3482 inflate_huft * FAR *, /* literal/length tree result */
3483 inflate_huft * FAR *)); /* distance tree result */
3484
3485extern int inflate_trees_free OF((
3486 inflate_huft *, /* tables to free */
3487 z_streamp )); /* for zfree function */
3488
3489/* --- inftrees.h */
3490
3491/* +++ infcodes.h */
3492/* infcodes.h -- header to use infcodes.c
3493 * Copyright (C) 1995-1996 Mark Adler
3494 * For conditions of distribution and use, see copyright notice in zlib.h
3495 */
3496
3497/* WARNING: this file should *not* be used by applications. It is
3498 part of the implementation of the compression library and is
3499 subject to change. Applications should only use zlib.h.
3500 */
3501
3502struct inflate_codes_state;
3503typedef struct inflate_codes_state FAR inflate_codes_statef;
3504
3505extern inflate_codes_statef *inflate_codes_new OF((
3506 uInt, uInt,
3507 inflate_huft *, inflate_huft *,
3508 z_streamp ));
3509
3510extern int inflate_codes OF((
3511 inflate_blocks_statef *,
3512 z_streamp ,
3513 int));
3514
3515extern void inflate_codes_free OF((
3516 inflate_codes_statef *,
3517 z_streamp ));
3518
3519/* --- infcodes.h */
3520
3521/* +++ infutil.h */
3522/* infutil.h -- types and macros common to blocks and codes
3523 * Copyright (C) 1995-1996 Mark Adler
3524 * For conditions of distribution and use, see copyright notice in zlib.h
3525 */
3526
3527/* WARNING: this file should *not* be used by applications. It is
3528 part of the implementation of the compression library and is
3529 subject to change. Applications should only use zlib.h.
3530 */
3531
3532#ifndef _INFUTIL_H
3533#define _INFUTIL_H
3534
3535typedef enum {
3536 TYPE, /* get type bits (3, including end bit) */
3537 LENS, /* get lengths for stored */
3538 STORED, /* processing stored block */
3539 TABLE, /* get table lengths */
3540 BTREE, /* get bit lengths tree for a dynamic block */
3541 DTREE, /* get length, distance trees for a dynamic block */
3542 CODES, /* processing fixed or dynamic block */
3543 DRY, /* output remaining window bytes */
3544 DONEB, /* finished last block, done */
3545 BADB} /* got a data error--stuck here */
3546inflate_block_mode;
3547
3548/* inflate blocks semi-private state */
3549struct inflate_blocks_state {
3550
3551 /* mode */
3552 inflate_block_mode mode; /* current inflate_block mode */
3553
3554 /* mode dependent information */
3555 union {
3556 uInt left; /* if STORED, bytes left to copy */
3557 struct {
3558 uInt table; /* table lengths (14 bits) */
3559 uInt index; /* index into blens (or border) */
3560 uIntf *blens; /* bit lengths of codes */
3561 uInt bb; /* bit length tree depth */
3562 inflate_huft *tb; /* bit length decoding tree */
3563 } trees; /* if DTREE, decoding info for trees */
3564 struct {
3565 inflate_huft *tl;
3566 inflate_huft *td; /* trees to free */
3567 inflate_codes_statef
3568 *codes;
3569 } decode; /* if CODES, current state */
3570 } sub; /* submode */
3571 uInt last; /* true if this block is the last block */
3572
3573 /* mode independent information */
3574 uInt bitk; /* bits in bit buffer */
3575 uLong bitb; /* bit buffer */
3576 Bytef *window; /* sliding window */
3577 Bytef *end; /* one byte after sliding window */
3578 Bytef *read; /* window read pointer */
3579 Bytef *write; /* window write pointer */
3580 check_func checkfn; /* check function */
3581 uLong check; /* check on output */
3582
3583};
3584
3585
3586/* defines for inflate input/output */
3587/* update pointers and return */
3588#define UPDBITS {s->bitb=b;s->bitk=k;}
3589#define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;}
3590#define UPDOUT {s->write=q;}
3591#define UPDATE {UPDBITS UPDIN UPDOUT}
3592#define LEAVE {UPDATE return inflate_flush(s,z,r);}
3593/* get bytes and bits */
3594#define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;}
3595#define NEEDBYTE {if(n)r=Z_OK;else LEAVE}
3596#define NEXTBYTE (n--,*p++)
3597#define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}}
3598#define DUMPBITS(j) {b>>=(j);k-=(j);}
3599/* output bytes */
3600#define WAVAIL (uInt)(q<s->read?s->read-q-1:s->end-q)
3601#define LOADOUT {q=s->write;m=(uInt)WAVAIL;}
3602#define WWRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}}
3603#define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT}
3604#define NEEDOUT {if(m==0){WWRAP if(m==0){FLUSH WWRAP if(m==0) LEAVE}}r=Z_OK;}
3605#define OUTBYTE(a) {*q++=(Byte)(a);m--;}
3606/* load local pointers */
3607#define LOAD {LOADIN LOADOUT}
3608
3609/* masks for lower bits (size given to avoid silly warnings with Visual C++) */
3610extern uInt inflate_mask[17];
3611
3612/* copy as much as possible from the sliding window to the output area */
3613extern int inflate_flush OF((
3614 inflate_blocks_statef *,
3615 z_streamp ,
3616 int));
3617
3618#ifndef NO_DUMMY_DECL
3619struct internal_state {int dummy;}; /* for buggy compilers */
3620#endif
3621
3622#endif
3623/* --- infutil.h */
3624
3625#ifndef NO_DUMMY_DECL
3626struct inflate_codes_state {int dummy;}; /* for buggy compilers */
3627#endif
3628
3629/* Table for deflate from PKZIP's appnote.txt. */
3630local const uInt border[] = { /* Order of the bit length code lengths */
3631 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
3632
3633/*
3634 Notes beyond the 1.93a appnote.txt:
3635
3636 1. Distance pointers never point before the beginning of the output
3637 stream.
3638 2. Distance pointers can point back across blocks, up to 32k away.
3639 3. There is an implied maximum of 7 bits for the bit length table and
3640 15 bits for the actual data.
3641 4. If only one code exists, then it is encoded using one bit. (Zero
3642 would be more efficient, but perhaps a little confusing.) If two
3643 codes exist, they are coded using one bit each (0 and 1).
3644 5. There is no way of sending zero distance codes--a dummy must be
3645 sent if there are none. (History: a pre 2.0 version of PKZIP would
3646 store blocks with no distance codes, but this was discovered to be
3647 too harsh a criterion.) Valid only for 1.93a. 2.04c does allow
3648 zero distance codes, which is sent as one code of zero bits in
3649 length.
3650 6. There are up to 286 literal/length codes. Code 256 represents the
3651 end-of-block. Note however that the static length tree defines
3652 288 codes just to fill out the Huffman codes. Codes 286 and 287
3653 cannot be used though, since there is no length base or extra bits
3654 defined for them. Similarily, there are up to 30 distance codes.
3655 However, static trees define 32 codes (all 5 bits) to fill out the
3656 Huffman codes, but the last two had better not show up in the data.
3657 7. Unzip can check dynamic Huffman blocks for complete code sets.
3658 The exception is that a single code would not be complete (see #4).
3659 8. The five bits following the block type is really the number of
3660 literal codes sent minus 257.
3661 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
3662 (1+6+6). Therefore, to output three times the length, you output
3663 three codes (1+1+1), whereas to output four times the same length,
3664 you only need two codes (1+3). Hmm.
3665 10. In the tree reconstruction algorithm, Code = Code + Increment
3666 only if BitLength(i) is not zero. (Pretty obvious.)
3667 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19)
3668 12. Note: length code 284 can represent 227-258, but length code 285
3669 really is 258. The last length deserves its own, short code
3670 since it gets used a lot in very redundant files. The length
3671 258 is special since 258 - 3 (the min match length) is 255.
3672 13. The literal/length and distance code bit lengths are read as a
3673 single stream of lengths. It is possible (and advantageous) for
3674 a repeat code (16, 17, or 18) to go across the boundary between
3675 the two sets of lengths.
3676 */
3677
3678
3679void inflate_blocks_reset(s, z, c)
3680inflate_blocks_statef *s;
3681z_streamp z;
3682uLongf *c;
3683{
3684 if (s->checkfn != Z_NULL)
3685 *c = s->check;
3686 if (s->mode == BTREE || s->mode == DTREE)
3687 ZFREE(z, s->sub.trees.blens);
3688 if (s->mode == CODES)
3689 {
3690 inflate_codes_free(s->sub.decode.codes, z);
3691 inflate_trees_free(s->sub.decode.td, z);
3692 inflate_trees_free(s->sub.decode.tl, z);
3693 }
3694 s->mode = TYPE;
3695 s->bitk = 0;
3696 s->bitb = 0;
3697 s->read = s->write = s->window;
3698 if (s->checkfn != Z_NULL)
3699 z->adler = s->check = (*s->checkfn)(0L, Z_NULL, 0);
3700 Trace((stderr, "inflate: blocks reset\n"));
3701}
3702
3703
3704inflate_blocks_statef *inflate_blocks_new(z, c, w)
3705z_streamp z;
3706check_func c;
3707uInt w;
3708{
3709 inflate_blocks_statef *s;
3710
3711 if ((s = (inflate_blocks_statef *)ZALLOC
3712 (z,1,sizeof(struct inflate_blocks_state))) == Z_NULL)
3713 return s;
3714 if ((s->window = (Bytef *)ZALLOC(z, 1, w)) == Z_NULL)
3715 {
3716 ZFREE(z, s);
3717 return Z_NULL;
3718 }
3719 s->end = s->window + w;
3720 s->checkfn = c;
3721 s->mode = TYPE;
3722 Trace((stderr, "inflate: blocks allocated\n"));
3723 inflate_blocks_reset(s, z, &s->check);
3724 return s;
3725}
3726
3727
3728#ifdef DEBUG_ZLIB
3729 extern uInt inflate_hufts;
3730#endif
3731int inflate_blocks(s, z, r)
3732inflate_blocks_statef *s;
3733z_streamp z;
3734int r;
3735{
3736 uInt t; /* temporary storage */
3737 uLong b; /* bit buffer */
3738 uInt k; /* bits in bit buffer */
3739 Bytef *p; /* input data pointer */
3740 uInt n; /* bytes available there */
3741 Bytef *q; /* output window write pointer */
3742 uInt m; /* bytes to end of window or read pointer */
3743
3744 /* copy input/output information to locals (UPDATE macro restores) */
3745 LOAD
3746
3747 /* process input based on current state */
3748 while (1) switch (s->mode)
3749 {
3750 case TYPE:
3751 NEEDBITS(3)
3752 t = (uInt)b & 7;
3753 s->last = t & 1;
3754 switch (t >> 1)
3755 {
3756 case 0: /* stored */
3757 Trace((stderr, "inflate: stored block%s\n",
3758 s->last ? " (last)" : ""));
3759 DUMPBITS(3)
3760 t = k & 7; /* go to byte boundary */
3761 DUMPBITS(t)
3762 s->mode = LENS; /* get length of stored block */
3763 break;
3764 case 1: /* fixed */
3765 Trace((stderr, "inflate: fixed codes block%s\n",
3766 s->last ? " (last)" : ""));
3767 {
3768 uInt bl, bd;
3769 inflate_huft *tl, *td;
3770
3771 inflate_trees_fixed(&bl, &bd, &tl, &td);
3772 s->sub.decode.codes = inflate_codes_new(bl, bd, tl, td, z);
3773 if (s->sub.decode.codes == Z_NULL)
3774 {
3775 r = Z_MEM_ERROR;
3776 LEAVE
3777 }
3778 s->sub.decode.tl = Z_NULL; /* don't try to free these */
3779 s->sub.decode.td = Z_NULL;
3780 }
3781 DUMPBITS(3)
3782 s->mode = CODES;
3783 break;
3784 case 2: /* dynamic */
3785 Trace((stderr, "inflate: dynamic codes block%s\n",
3786 s->last ? " (last)" : ""));
3787 DUMPBITS(3)
3788 s->mode = TABLE;
3789 break;
3790 case 3: /* illegal */
3791 DUMPBITS(3)
3792 s->mode = BADB;
3793 z->msg = (char*)"invalid block type";
3794 r = Z_DATA_ERROR;
3795 LEAVE
3796 }
3797 break;
3798 case LENS:
3799 NEEDBITS(32)
3800 if ((((~b) >> 16) & 0xffff) != (b & 0xffff))
3801 {
3802 s->mode = BADB;
3803 z->msg = (char*)"invalid stored block lengths";
3804 r = Z_DATA_ERROR;
3805 LEAVE
3806 }
3807 s->sub.left = (uInt)b & 0xffff;
3808 b = k = 0; /* dump bits */
3809 Tracev((stderr, "inflate: stored length %u\n", s->sub.left));
3810 s->mode = s->sub.left ? STORED : (s->last ? DRY : TYPE);
3811 break;
3812 case STORED:
3813 if (n == 0)
3814 LEAVE
3815 NEEDOUT
3816 t = s->sub.left;
3817 if (t > n) t = n;
3818 if (t > m) t = m;
3819 zmemcpy(q, p, t);
3820 p += t; n -= t;
3821 q += t; m -= t;
3822 if ((s->sub.left -= t) != 0)
3823 break;
3824 Tracev((stderr, "inflate: stored end, %lu total out\n",
3825 z->total_out + (q >= s->read ? q - s->read :
3826 (s->end - s->read) + (q - s->window))));
3827 s->mode = s->last ? DRY : TYPE;
3828 break;
3829 case TABLE:
3830 NEEDBITS(14)
3831 s->sub.trees.table = t = (uInt)b & 0x3fff;
3832#ifndef PKZIP_BUG_WORKAROUND
3833 if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29)
3834 {
3835 s->mode = BADB;
3836 z->msg = (char*)"too many length or distance symbols";
3837 r = Z_DATA_ERROR;
3838 LEAVE
3839 }
3840#endif
3841 t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
3842 if (t < 19)
3843 t = 19;
3844 if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL)
3845 {
3846 r = Z_MEM_ERROR;
3847 LEAVE
3848 }
3849 DUMPBITS(14)
3850 s->sub.trees.index = 0;
3851 Tracev((stderr, "inflate: table sizes ok\n"));
3852 s->mode = BTREE;
3853 case BTREE:
3854 while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10))
3855 {
3856 NEEDBITS(3)
3857 s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7;
3858 DUMPBITS(3)
3859 }
3860 while (s->sub.trees.index < 19)
3861 s->sub.trees.blens[border[s->sub.trees.index++]] = 0;
3862 s->sub.trees.bb = 7;
3863 t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb,
3864 &s->sub.trees.tb, z);
3865 if (t != Z_OK)
3866 {
3867 ZFREE(z, s->sub.trees.blens);
3868 r = t;
3869 if (r == Z_DATA_ERROR)
3870 s->mode = BADB;
3871 LEAVE
3872 }
3873 s->sub.trees.index = 0;
3874 Tracev((stderr, "inflate: bits tree ok\n"));
3875 s->mode = DTREE;
3876 case DTREE:
3877 while (t = s->sub.trees.table,
3878 s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f))
3879 {
3880 inflate_huft *h;
3881 uInt i, j, c;
3882
3883 t = s->sub.trees.bb;
3884 NEEDBITS(t)
3885 h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]);
3886 t = h->word.what.Bits;
3887 c = h->more.Base;
3888 if (c < 16)
3889 {
3890 DUMPBITS(t)
3891 s->sub.trees.blens[s->sub.trees.index++] = c;
3892 }
3893 else /* c == 16..18 */
3894 {
3895 i = c == 18 ? 7 : c - 14;
3896 j = c == 18 ? 11 : 3;
3897 NEEDBITS(t + i)
3898 DUMPBITS(t)
3899 j += (uInt)b & inflate_mask[i];
3900 DUMPBITS(i)
3901 i = s->sub.trees.index;
3902 t = s->sub.trees.table;
3903 if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) ||
3904 (c == 16 && i < 1))
3905 {
3906 inflate_trees_free(s->sub.trees.tb, z);
3907 ZFREE(z, s->sub.trees.blens);
3908 s->mode = BADB;
3909 z->msg = (char*)"invalid bit length repeat";
3910 r = Z_DATA_ERROR;
3911 LEAVE
3912 }
3913 c = c == 16 ? s->sub.trees.blens[i - 1] : 0;
3914 do {
3915 s->sub.trees.blens[i++] = c;
3916 } while (--j);
3917 s->sub.trees.index = i;
3918 }
3919 }
3920 inflate_trees_free(s->sub.trees.tb, z);
3921 s->sub.trees.tb = Z_NULL;
3922 {
3923 uInt bl, bd;
3924 inflate_huft *tl, *td;
3925 inflate_codes_statef *c;
3926
3927 bl = 9; /* must be <= 9 for lookahead assumptions */
3928 bd = 6; /* must be <= 9 for lookahead assumptions */
3929 t = s->sub.trees.table;
3930#ifdef DEBUG_ZLIB
3931 inflate_hufts = 0;
3932#endif
3933 t = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f),
3934 s->sub.trees.blens, &bl, &bd, &tl, &td, z);
3935 ZFREE(z, s->sub.trees.blens);
3936 if (t != Z_OK)
3937 {
3938 if (t == (uInt)Z_DATA_ERROR)
3939 s->mode = BADB;
3940 r = t;
3941 LEAVE
3942 }
3943 Tracev((stderr, "inflate: trees ok, %d * %d bytes used\n",
3944 inflate_hufts, sizeof(inflate_huft)));
3945 if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL)
3946 {
3947 inflate_trees_free(td, z);
3948 inflate_trees_free(tl, z);
3949 r = Z_MEM_ERROR;
3950 LEAVE
3951 }
3952 s->sub.decode.codes = c;
3953 s->sub.decode.tl = tl;
3954 s->sub.decode.td = td;
3955 }
3956 s->mode = CODES;
3957 case CODES:
3958 UPDATE
3959 if ((r = inflate_codes(s, z, r)) != Z_STREAM_END)
3960 return inflate_flush(s, z, r);
3961 r = Z_OK;
3962 inflate_codes_free(s->sub.decode.codes, z);
3963 inflate_trees_free(s->sub.decode.td, z);
3964 inflate_trees_free(s->sub.decode.tl, z);
3965 LOAD
3966 Tracev((stderr, "inflate: codes end, %lu total out\n",
3967 z->total_out + (q >= s->read ? q - s->read :
3968 (s->end - s->read) + (q - s->window))));
3969 if (!s->last)
3970 {
3971 s->mode = TYPE;
3972 break;
3973 }
3974 if (k > 7) /* return unused byte, if any */
3975 {
3976 Assert(k < 16, "inflate_codes grabbed too many bytes")
3977 k -= 8;
3978 n++;
3979 p--; /* can always return one */
3980 }
3981 s->mode = DRY;
3982 case DRY:
3983 FLUSH
3984 if (s->read != s->write)
3985 LEAVE
3986 s->mode = DONEB;
3987 case DONEB:
3988 r = Z_STREAM_END;
3989 LEAVE
3990 case BADB:
3991 r = Z_DATA_ERROR;
3992 LEAVE
3993 default:
3994 r = Z_STREAM_ERROR;
3995 LEAVE
3996 }
3997}
3998
3999
4000int inflate_blocks_free(s, z, c)
4001inflate_blocks_statef *s;
4002z_streamp z;
4003uLongf *c;
4004{
4005 inflate_blocks_reset(s, z, c);
4006 ZFREE(z, s->window);
4007 ZFREE(z, s);
4008 Trace((stderr, "inflate: blocks freed\n"));
4009 return Z_OK;
4010}
4011
4012
4013void inflate_set_dictionary(s, d, n)
4014inflate_blocks_statef *s;
4015const Bytef *d;
4016uInt n;
4017{
4018 zmemcpy((charf *)s->window, d, n);
4019 s->read = s->write = s->window + n;
4020}
4021
4022/*
4023 * This subroutine adds the data at next_in/avail_in to the output history
4024 * without performing any output. The output buffer must be "caught up";
4025 * i.e. no pending output (hence s->read equals s->write), and the state must
4026 * be BLOCKS (i.e. we should be willing to see the start of a series of
4027 * BLOCKS). On exit, the output will also be caught up, and the checksum
4028 * will have been updated if need be.
4029 */
4030int inflate_addhistory(s, z)
4031inflate_blocks_statef *s;
4032z_stream *z;
4033{
4034 uLong b; /* bit buffer */ /* NOT USED HERE */
4035 uInt k; /* bits in bit buffer */ /* NOT USED HERE */
4036 uInt t; /* temporary storage */
4037 Bytef *p; /* input data pointer */
4038 uInt n; /* bytes available there */
4039 Bytef *q; /* output window write pointer */
4040 uInt m; /* bytes to end of window or read pointer */
4041
4042 if (s->read != s->write)
4043 return Z_STREAM_ERROR;
4044 if (s->mode != TYPE)
4045 return Z_DATA_ERROR;
4046
4047 /* we're ready to rock */
4048 LOAD
4049 /* while there is input ready, copy to output buffer, moving
4050 * pointers as needed.
4051 */
4052 while (n) {
4053 t = n; /* how many to do */
4054 /* is there room until end of buffer? */
4055 if (t > m) t = m;
4056 /* update check information */
4057 if (s->checkfn != Z_NULL)
4058 s->check = (*s->checkfn)(s->check, q, t);
4059 zmemcpy(q, p, t);
4060 q += t;
4061 p += t;
4062 n -= t;
4063 z->total_out += t;
4064 s->read = q; /* drag read pointer forward */
4065/* WWRAP */ /* expand WWRAP macro by hand to handle s->read */
4066 if (q == s->end) {
4067 s->read = q = s->window;
4068 m = WAVAIL;
4069 }
4070 }
4071 UPDATE
4072 return Z_OK;
4073}
4074
4075
4076/*
4077 * At the end of a Deflate-compressed PPP packet, we expect to have seen
4078 * a `stored' block type value but not the (zero) length bytes.
4079 */
4080int inflate_packet_flush(s)
4081 inflate_blocks_statef *s;
4082{
4083 if (s->mode != LENS)
4084 return Z_DATA_ERROR;
4085 s->mode = TYPE;
4086 return Z_OK;
4087}
4088/* --- infblock.c */
4089
4090/* +++ inftrees.c */
4091/* inftrees.c -- generate Huffman trees for efficient decoding
4092 * Copyright (C) 1995-1996 Mark Adler
4093 * For conditions of distribution and use, see copyright notice in zlib.h
4094 */
4095
4096/* #include "zutil.h" */
4097/* #include "inftrees.h" */
4098
4099char inflate_copyright[] = " inflate 1.0.4 Copyright 1995-1996 Mark Adler ";
4100/*
4101 If you use the zlib library in a product, an acknowledgment is welcome
4102 in the documentation of your product. If for some reason you cannot
4103 include such an acknowledgment, I would appreciate that you keep this
4104 copyright string in the executable of your product.
4105 */
4106
4107#ifndef NO_DUMMY_DECL
4108struct internal_state {int dummy;}; /* for buggy compilers */
4109#endif
4110
4111/* simplify the use of the inflate_huft type with some defines */
4112#define base more.Base
4113#define next more.Next
4114#define exop word.what.Exop
4115#define bits word.what.Bits
4116
4117
4118local int huft_build OF((
4119 uIntf *, /* code lengths in bits */
4120 uInt, /* number of codes */
4121 uInt, /* number of "simple" codes */
4122 const uIntf *, /* list of base values for non-simple codes */
4123 const uIntf *, /* list of extra bits for non-simple codes */
4124 inflate_huft * FAR*,/* result: starting table */
4125 uIntf *, /* maximum lookup bits (returns actual) */
4126 z_streamp )); /* for zalloc function */
4127
4128local voidpf falloc OF((
4129 voidpf, /* opaque pointer (not used) */
4130 uInt, /* number of items */
4131 uInt)); /* size of item */
4132
4133/* Tables for deflate from PKZIP's appnote.txt. */
4134local const uInt cplens[31] = { /* Copy lengths for literal codes 257..285 */
4135 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
4136 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
4137 /* see note #13 above about 258 */
4138local const uInt cplext[31] = { /* Extra bits for literal codes 257..285 */
4139 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
4140 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 112, 112}; /* 112==invalid */
4141local const uInt cpdist[30] = { /* Copy offsets for distance codes 0..29 */
4142 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
4143 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
4144 8193, 12289, 16385, 24577};
4145local const uInt cpdext[30] = { /* Extra bits for distance codes */
4146 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
4147 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
4148 12, 12, 13, 13};
4149
4150/*
4151 Huffman code decoding is performed using a multi-level table lookup.
4152 The fastest way to decode is to simply build a lookup table whose
4153 size is determined by the longest code. However, the time it takes
4154 to build this table can also be a factor if the data being decoded
4155 is not very long. The most common codes are necessarily the
4156 shortest codes, so those codes dominate the decoding time, and hence
4157 the speed. The idea is you can have a shorter table that decodes the
4158 shorter, more probable codes, and then point to subsidiary tables for
4159 the longer codes. The time it costs to decode the longer codes is
4160 then traded against the time it takes to make longer tables.
4161
4162 This results of this trade are in the variables lbits and dbits
4163 below. lbits is the number of bits the first level table for literal/
4164 length codes can decode in one step, and dbits is the same thing for
4165 the distance codes. Subsequent tables are also less than or equal to
4166 those sizes. These values may be adjusted either when all of the
4167 codes are shorter than that, in which case the longest code length in
4168 bits is used, or when the shortest code is *longer* than the requested
4169 table size, in which case the length of the shortest code in bits is
4170 used.
4171
4172 There are two different values for the two tables, since they code a
4173 different number of possibilities each. The literal/length table
4174 codes 286 possible values, or in a flat code, a little over eight
4175 bits. The distance table codes 30 possible values, or a little less
4176 than five bits, flat. The optimum values for speed end up being
4177 about one bit more than those, so lbits is 8+1 and dbits is 5+1.
4178 The optimum values may differ though from machine to machine, and
4179 possibly even between compilers. Your mileage may vary.
4180 */
4181
4182
4183/* If BMAX needs to be larger than 16, then h and x[] should be uLong. */
4184#define BMAX 15 /* maximum bit length of any code */
4185#define N_MAX 288 /* maximum number of codes in any set */
4186
4187#ifdef DEBUG_ZLIB
4188 uInt inflate_hufts;
4189#endif
4190
4191local int huft_build(b, n, s, d, e, t, m, zs)
4192uIntf *b; /* code lengths in bits (all assumed <= BMAX) */
4193uInt n; /* number of codes (assumed <= N_MAX) */
4194uInt s; /* number of simple-valued codes (0..s-1) */
4195const uIntf *d; /* list of base values for non-simple codes */
4196const uIntf *e; /* list of extra bits for non-simple codes */
4197inflate_huft * FAR *t; /* result: starting table */
4198uIntf *m; /* maximum lookup bits, returns actual */
4199z_streamp zs; /* for zalloc function */
4200/* Given a list of code lengths and a maximum table size, make a set of
4201 tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR
4202 if the given code set is incomplete (the tables are still built in this
4203 case), Z_DATA_ERROR if the input is invalid (an over-subscribed set of
4204 lengths), or Z_MEM_ERROR if not enough memory. */
4205{
4206
4207 uInt a; /* counter for codes of length k */
4208 uInt c[BMAX+1]; /* bit length count table */
4209 uInt f; /* i repeats in table every f entries */
4210 int g; /* maximum code length */
4211 int h; /* table level */
4212 register uInt i; /* counter, current code */
4213 register uInt j; /* counter */
4214 register int k; /* number of bits in current code */
4215 int l; /* bits per table (returned in m) */
4216 register uIntf *p; /* pointer into c[], b[], or v[] */
4217 inflate_huft *q; /* points to current table */
4218 struct inflate_huft_s r; /* table entry for structure assignment */
4219 inflate_huft *u[BMAX]; /* table stack */
4220 uInt v[N_MAX]; /* values in order of bit length */
4221 register int w; /* bits before this table == (l * h) */
4222 uInt x[BMAX+1]; /* bit offsets, then code stack */
4223 uIntf *xp; /* pointer into x */
4224 int y; /* number of dummy codes added */
4225 uInt z; /* number of entries in current table */
4226
4227
4228 /* Generate counts for each bit length */
4229 p = c;
4230#define C0 *p++ = 0;
4231#define C2 C0 C0 C0 C0
4232#define C4 C2 C2 C2 C2
4233 C4 /* clear c[]--assume BMAX+1 is 16 */
4234 p = b; i = n;
4235 do {
4236 c[*p++]++; /* assume all entries <= BMAX */
4237 } while (--i);
4238 if (c[0] == n) /* null input--all zero length codes */
4239 {
4240 *t = (inflate_huft *)Z_NULL;
4241 *m = 0;
4242 return Z_OK;
4243 }
4244
4245
4246 /* Find minimum and maximum length, bound *m by those */
4247 l = *m;
4248 for (j = 1; j <= BMAX; j++)
4249 if (c[j])
4250 break;
4251 k = j; /* minimum code length */
4252 if ((uInt)l < j)
4253 l = j;
4254 for (i = BMAX; i; i--)
4255 if (c[i])
4256 break;
4257 g = i; /* maximum code length */
4258 if ((uInt)l > i)
4259 l = i;
4260 *m = l;
4261
4262
4263 /* Adjust last length count to fill out codes, if needed */
4264 for (y = 1 << j; j < i; j++, y <<= 1)
4265 if ((y -= c[j]) < 0)
4266 return Z_DATA_ERROR;
4267 if ((y -= c[i]) < 0)
4268 return Z_DATA_ERROR;
4269 c[i] += y;
4270
4271
4272 /* Generate starting offsets into the value table for each length */
4273 x[1] = j = 0;
4274 p = c + 1; xp = x + 2;
4275 while (--i) { /* note that i == g from above */
4276 *xp++ = (j += *p++);
4277 }
4278
4279
4280 /* Make a table of values in order of bit lengths */
4281 p = b; i = 0;
4282 do {
4283 if ((j = *p++) != 0)
4284 v[x[j]++] = i;
4285 } while (++i < n);
4286 n = x[g]; /* set n to length of v */
4287
4288
4289 /* Generate the Huffman codes and for each, make the table entries */
4290 x[0] = i = 0; /* first Huffman code is zero */
4291 p = v; /* grab values in bit order */
4292 h = -1; /* no tables yet--level -1 */
4293 w = -l; /* bits decoded == (l * h) */
4294 u[0] = (inflate_huft *)Z_NULL; /* just to keep compilers happy */
4295 q = (inflate_huft *)Z_NULL; /* ditto */
4296 z = 0; /* ditto */
4297
4298 /* go through the bit lengths (k already is bits in shortest code) */
4299 for (; k <= g; k++)
4300 {
4301 a = c[k];
4302 while (a--)
4303 {
4304 /* here i is the Huffman code of length k bits for value *p */
4305 /* make tables up to required level */
4306 while (k > w + l)
4307 {
4308 h++;
4309 w += l; /* previous table always l bits */
4310
4311 /* compute minimum size table less than or equal to l bits */
4312 z = g - w;
4313 z = z > (uInt)l ? l : z; /* table size upper limit */
4314 if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */
4315 { /* too few codes for k-w bit table */
4316 f -= a + 1; /* deduct codes from patterns left */
4317 xp = c + k;
4318 if (j < z)
4319 while (++j < z) /* try smaller tables up to z bits */
4320 {
4321 if ((f <<= 1) <= *++xp)
4322 break; /* enough codes to use up j bits */
4323 f -= *xp; /* else deduct codes from patterns */
4324 }
4325 }
4326 z = 1 << j; /* table entries for j-bit table */
4327
4328 /* allocate and link in new table */
4329 if ((q = (inflate_huft *)ZALLOC
4330 (zs,z + 1,sizeof(inflate_huft))) == Z_NULL)
4331 {
4332 if (h)
4333 inflate_trees_free(u[0], zs);
4334 return Z_MEM_ERROR; /* not enough memory */
4335 }
4336#ifdef DEBUG_ZLIB
4337 inflate_hufts += z + 1;
4338#endif
4339 *t = q + 1; /* link to list for huft_free() */
4340 *(t = &(q->next)) = Z_NULL;
4341 u[h] = ++q; /* table starts after link */
4342
4343 /* connect to last table, if there is one */
4344 if (h)
4345 {
4346 x[h] = i; /* save pattern for backing up */
4347 r.bits = (Byte)l; /* bits to dump before this table */
4348 r.exop = (Byte)j; /* bits in this table */
4349 r.next = q; /* pointer to this table */
4350 j = i >> (w - l); /* (get around Turbo C bug) */
4351 u[h-1][j] = r; /* connect to last table */
4352 }
4353 }
4354
4355 /* set up table entry in r */
4356 r.bits = (Byte)(k - w);
4357 if (p >= v + n)
4358 r.exop = 128 + 64; /* out of values--invalid code */
4359 else if (*p < s)
4360 {
4361 r.exop = (Byte)(*p < 256 ? 0 : 32 + 64); /* 256 is end-of-block */
4362 r.base = *p++; /* simple code is just the value */
4363 }
4364 else
4365 {
4366 r.exop = (Byte)(e[*p - s] + 16 + 64);/* non-simple--look up in lists */
4367 r.base = d[*p++ - s];
4368 }
4369
4370 /* fill code-like entries with r */
4371 f = 1 << (k - w);
4372 for (j = i >> w; j < z; j += f)
4373 q[j] = r;
4374
4375 /* backwards increment the k-bit code i */
4376 for (j = 1 << (k - 1); i & j; j >>= 1)
4377 i ^= j;
4378 i ^= j;
4379
4380 /* backup over finished tables */
4381 while ((i & ((1 << w) - 1)) != x[h])
4382 {
4383 h--; /* don't need to update q */
4384 w -= l;
4385 }
4386 }
4387 }
4388
4389
4390 /* Return Z_BUF_ERROR if we were given an incomplete table */
4391 return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK;
4392}
4393
4394
4395int inflate_trees_bits(c, bb, tb, z)
4396uIntf *c; /* 19 code lengths */
4397uIntf *bb; /* bits tree desired/actual depth */
4398inflate_huft * FAR *tb; /* bits tree result */
4399z_streamp z; /* for zfree function */
4400{
4401 int r;
4402
4403 r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL, tb, bb, z);
4404 if (r == Z_DATA_ERROR)
4405 z->msg = (char*)"oversubscribed dynamic bit lengths tree";
4406 else if (r == Z_BUF_ERROR || *bb == 0)
4407 {
4408 inflate_trees_free(*tb, z);
4409 z->msg = (char*)"incomplete dynamic bit lengths tree";
4410 r = Z_DATA_ERROR;
4411 }
4412 return r;
4413}
4414
4415
4416int inflate_trees_dynamic(nl, nd, c, bl, bd, tl, td, z)
4417uInt nl; /* number of literal/length codes */
4418uInt nd; /* number of distance codes */
4419uIntf *c; /* that many (total) code lengths */
4420uIntf *bl; /* literal desired/actual bit depth */
4421uIntf *bd; /* distance desired/actual bit depth */
4422inflate_huft * FAR *tl; /* literal/length tree result */
4423inflate_huft * FAR *td; /* distance tree result */
4424z_streamp z; /* for zfree function */
4425{
4426 int r;
4427
4428 /* build literal/length tree */
4429 r = huft_build(c, nl, 257, cplens, cplext, tl, bl, z);
4430 if (r != Z_OK || *bl == 0)
4431 {
4432 if (r == Z_DATA_ERROR)
4433 z->msg = (char*)"oversubscribed literal/length tree";
4434 else if (r != Z_MEM_ERROR)
4435 {
4436 inflate_trees_free(*tl, z);
4437 z->msg = (char*)"incomplete literal/length tree";
4438 r = Z_DATA_ERROR;
4439 }
4440 return r;
4441 }
4442
4443 /* build distance tree */
4444 r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, z);
4445 if (r != Z_OK || (*bd == 0 && nl > 257))
4446 {
4447 if (r == Z_DATA_ERROR)
4448 z->msg = (char*)"oversubscribed distance tree";
4449 else if (r == Z_BUF_ERROR) {
4450#ifdef PKZIP_BUG_WORKAROUND
4451 r = Z_OK;
4452 }
4453#else
4454 inflate_trees_free(*td, z);
4455 z->msg = (char*)"incomplete distance tree";
4456 r = Z_DATA_ERROR;
4457 }
4458 else if (r != Z_MEM_ERROR)
4459 {
4460 z->msg = (char*)"empty distance tree with lengths";
4461 r = Z_DATA_ERROR;
4462 }
4463 inflate_trees_free(*tl, z);
4464 return r;
4465#endif
4466 }
4467
4468 /* done */
4469 return Z_OK;
4470}
4471
4472
4473/* build fixed tables only once--keep them here */
4474local int fixed_built = 0;
4475#define FIXEDH 530 /* number of hufts used by fixed tables */
4476local inflate_huft fixed_mem[FIXEDH];
4477local uInt fixed_bl;
4478local uInt fixed_bd;
4479local inflate_huft *fixed_tl;
4480local inflate_huft *fixed_td;
4481
4482
4483local voidpf falloc(q, n, s)
4484voidpf q; /* opaque pointer */
4485uInt n; /* number of items */
4486uInt s; /* size of item */
4487{
4488 Assert(s == sizeof(inflate_huft) && n <= *(intf *)q,
4489 "inflate_trees falloc overflow");
4490 *(intf *)q -= n+s-s; /* s-s to avoid warning */
4491 return (voidpf)(fixed_mem + *(intf *)q);
4492}
4493
4494
4495int inflate_trees_fixed(bl, bd, tl, td)
4496uIntf *bl; /* literal desired/actual bit depth */
4497uIntf *bd; /* distance desired/actual bit depth */
4498inflate_huft * FAR *tl; /* literal/length tree result */
4499inflate_huft * FAR *td; /* distance tree result */
4500{
4501 /* build fixed tables if not already (multiple overlapped executions ok) */
4502 if (!fixed_built)
4503 {
4504 int k; /* temporary variable */
4505 unsigned c[288]; /* length list for huft_build */
4506 z_stream z; /* for falloc function */
4507 int f = FIXEDH; /* number of hufts left in fixed_mem */
4508
4509 /* set up fake z_stream for memory routines */
4510 z.zalloc = falloc;
4511 z.zfree = Z_NULL;
4512 z.opaque = (voidpf)&f;
4513
4514 /* literal table */
4515 for (k = 0; k < 144; k++)
4516 c[k] = 8;
4517 for (; k < 256; k++)
4518 c[k] = 9;
4519 for (; k < 280; k++)
4520 c[k] = 7;
4521 for (; k < 288; k++)
4522 c[k] = 8;
4523 fixed_bl = 7;
4524 huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl, &z);
4525
4526 /* distance table */
4527 for (k = 0; k < 30; k++)
4528 c[k] = 5;
4529 fixed_bd = 5;
4530 huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd, &z);
4531
4532 /* done */
4533 Assert(f == 0, "invalid build of fixed tables");
4534 fixed_built = 1;
4535 }
4536 *bl = fixed_bl;
4537 *bd = fixed_bd;
4538 *tl = fixed_tl;
4539 *td = fixed_td;
4540 return Z_OK;
4541}
4542
4543
4544int inflate_trees_free(t, z)
4545inflate_huft *t; /* table to free */
4546z_streamp z; /* for zfree function */
4547/* Free the malloc'ed tables built by huft_build(), which makes a linked
4548 list of the tables it made, with the links in a dummy first entry of
4549 each table. */
4550{
4551 register inflate_huft *p, *q, *r;
4552
4553 /* Reverse linked list */
4554 p = Z_NULL;
4555 q = t;
4556 while (q != Z_NULL)
4557 {
4558 r = (q - 1)->next;
4559 (q - 1)->next = p;
4560 p = q;
4561 q = r;
4562 }
4563 /* Go through linked list, freeing from the malloced (t[-1]) address. */
4564 while (p != Z_NULL)
4565 {
4566 q = (--p)->next;
4567 ZFREE(z,p);
4568 p = q;
4569 }
4570 return Z_OK;
4571}
4572/* --- inftrees.c */
4573
4574/* +++ infcodes.c */
4575/* infcodes.c -- process literals and length/distance pairs
4576 * Copyright (C) 1995-1996 Mark Adler
4577 * For conditions of distribution and use, see copyright notice in zlib.h
4578 */
4579
4580/* #include "zutil.h" */
4581/* #include "inftrees.h" */
4582/* #include "infblock.h" */
4583/* #include "infcodes.h" */
4584/* #include "infutil.h" */
4585
4586/* +++ inffast.h */
4587/* inffast.h -- header to use inffast.c
4588 * Copyright (C) 1995-1996 Mark Adler
4589 * For conditions of distribution and use, see copyright notice in zlib.h
4590 */
4591
4592/* WARNING: this file should *not* be used by applications. It is
4593 part of the implementation of the compression library and is
4594 subject to change. Applications should only use zlib.h.
4595 */
4596
4597extern int inflate_fast OF((
4598 uInt,
4599 uInt,
4600 inflate_huft *,
4601 inflate_huft *,
4602 inflate_blocks_statef *,
4603 z_streamp ));
4604/* --- inffast.h */
4605
4606/* simplify the use of the inflate_huft type with some defines */
4607#define base more.Base
4608#define next more.Next
4609#define exop word.what.Exop
4610#define bits word.what.Bits
4611
4612/* inflate codes private state */
4613struct inflate_codes_state {
4614
4615 /* mode */
4616 enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
4617 START, /* x: set up for LEN */
4618 LEN, /* i: get length/literal/eob next */
4619 LENEXT, /* i: getting length extra (have base) */
4620 DIST, /* i: get distance next */
4621 DISTEXT, /* i: getting distance extra */
4622 COPY, /* o: copying bytes in window, waiting for space */
4623 LIT, /* o: got literal, waiting for output space */
4624 WASH, /* o: got eob, possibly still output waiting */
4625 END, /* x: got eob and all data flushed */
4626 BADCODE} /* x: got error */
4627 mode; /* current inflate_codes mode */
4628
4629 /* mode dependent information */
4630 uInt len;
4631 union {
4632 struct {
4633 inflate_huft *tree; /* pointer into tree */
4634 uInt need; /* bits needed */
4635 } code; /* if LEN or DIST, where in tree */
4636 uInt lit; /* if LIT, literal */
4637 struct {
4638 uInt get; /* bits to get for extra */
4639 uInt dist; /* distance back to copy from */
4640 } copy; /* if EXT or COPY, where and how much */
4641 } sub; /* submode */
4642
4643 /* mode independent information */
4644 Byte lbits; /* ltree bits decoded per branch */
4645 Byte dbits; /* dtree bits decoder per branch */
4646 inflate_huft *ltree; /* literal/length/eob tree */
4647 inflate_huft *dtree; /* distance tree */
4648
4649};
4650
4651
4652inflate_codes_statef *inflate_codes_new(bl, bd, tl, td, z)
4653uInt bl, bd;
4654inflate_huft *tl;
4655inflate_huft *td; /* need separate declaration for Borland C++ */
4656z_streamp z;
4657{
4658 inflate_codes_statef *c;
4659
4660 if ((c = (inflate_codes_statef *)
4661 ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL)
4662 {
4663 c->mode = START;
4664 c->lbits = (Byte)bl;
4665 c->dbits = (Byte)bd;
4666 c->ltree = tl;
4667 c->dtree = td;
4668 Tracev((stderr, "inflate: codes new\n"));
4669 }
4670 return c;
4671}
4672
4673
4674int inflate_codes(s, z, r)
4675inflate_blocks_statef *s;
4676z_streamp z;
4677int r;
4678{
4679 uInt j; /* temporary storage */
4680 inflate_huft *t; /* temporary pointer */
4681 uInt e; /* extra bits or operation */
4682 uLong b; /* bit buffer */
4683 uInt k; /* bits in bit buffer */
4684 Bytef *p; /* input data pointer */
4685 uInt n; /* bytes available there */
4686 Bytef *q; /* output window write pointer */
4687 uInt m; /* bytes to end of window or read pointer */
4688 Bytef *f; /* pointer to copy strings from */
4689 inflate_codes_statef *c = s->sub.decode.codes; /* codes state */
4690
4691 /* copy input/output information to locals (UPDATE macro restores) */
4692 LOAD
4693
4694 /* process input and output based on current state */
4695 while (1) switch (c->mode)
4696 { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
4697 case START: /* x: set up for LEN */
4698#ifndef SLOW
4699 if (m >= 258 && n >= 10)
4700 {
4701 UPDATE
4702 r = inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z);
4703 LOAD
4704 if (r != Z_OK)
4705 {
4706 c->mode = r == Z_STREAM_END ? WASH : BADCODE;
4707 break;
4708 }
4709 }
4710#endif /* !SLOW */
4711 c->sub.code.need = c->lbits;
4712 c->sub.code.tree = c->ltree;
4713 c->mode = LEN;
4714 case LEN: /* i: get length/literal/eob next */
4715 j = c->sub.code.need;
4716 NEEDBITS(j)
4717 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
4718 DUMPBITS(t->bits)
4719 e = (uInt)(t->exop);
4720 if (e == 0) /* literal */
4721 {
4722 c->sub.lit = t->base;
4723 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
4724 "inflate: literal '%c'\n" :
4725 "inflate: literal 0x%02x\n", t->base));
4726 c->mode = LIT;
4727 break;
4728 }
4729 if (e & 16) /* length */
4730 {
4731 c->sub.copy.get = e & 15;
4732 c->len = t->base;
4733 c->mode = LENEXT;
4734 break;
4735 }
4736 if ((e & 64) == 0) /* next table */
4737 {
4738 c->sub.code.need = e;
4739 c->sub.code.tree = t->next;
4740 break;
4741 }
4742 if (e & 32) /* end of block */
4743 {
4744 Tracevv((stderr, "inflate: end of block\n"));
4745 c->mode = WASH;
4746 break;
4747 }
4748 c->mode = BADCODE; /* invalid code */
4749 z->msg = (char*)"invalid literal/length code";
4750 r = Z_DATA_ERROR;
4751 LEAVE
4752 case LENEXT: /* i: getting length extra (have base) */
4753 j = c->sub.copy.get;
4754 NEEDBITS(j)
4755 c->len += (uInt)b & inflate_mask[j];
4756 DUMPBITS(j)
4757 c->sub.code.need = c->dbits;
4758 c->sub.code.tree = c->dtree;
4759 Tracevv((stderr, "inflate: length %u\n", c->len));
4760 c->mode = DIST;
4761 case DIST: /* i: get distance next */
4762 j = c->sub.code.need;
4763 NEEDBITS(j)
4764 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
4765 DUMPBITS(t->bits)
4766 e = (uInt)(t->exop);
4767 if (e & 16) /* distance */
4768 {
4769 c->sub.copy.get = e & 15;
4770 c->sub.copy.dist = t->base;
4771 c->mode = DISTEXT;
4772 break;
4773 }
4774 if ((e & 64) == 0) /* next table */
4775 {
4776 c->sub.code.need = e;
4777 c->sub.code.tree = t->next;
4778 break;
4779 }
4780 c->mode = BADCODE; /* invalid code */
4781 z->msg = (char*)"invalid distance code";
4782 r = Z_DATA_ERROR;
4783 LEAVE
4784 case DISTEXT: /* i: getting distance extra */
4785 j = c->sub.copy.get;
4786 NEEDBITS(j)
4787 c->sub.copy.dist += (uInt)b & inflate_mask[j];
4788 DUMPBITS(j)
4789 Tracevv((stderr, "inflate: distance %u\n", c->sub.copy.dist));
4790 c->mode = COPY;
4791 case COPY: /* o: copying bytes in window, waiting for space */
4792#ifndef __TURBOC__ /* Turbo C bug for following expression */
4793 f = (uInt)(q - s->window) < c->sub.copy.dist ?
4794 s->end - (c->sub.copy.dist - (q - s->window)) :
4795 q - c->sub.copy.dist;
4796#else
4797 f = q - c->sub.copy.dist;
4798 if ((uInt)(q - s->window) < c->sub.copy.dist)
4799 f = s->end - (c->sub.copy.dist - (uInt)(q - s->window));
4800#endif
4801 while (c->len)
4802 {
4803 NEEDOUT
4804 OUTBYTE(*f++)
4805 if (f == s->end)
4806 f = s->window;
4807 c->len--;
4808 }
4809 c->mode = START;
4810 break;
4811 case LIT: /* o: got literal, waiting for output space */
4812 NEEDOUT
4813 OUTBYTE(c->sub.lit)
4814 c->mode = START;
4815 break;
4816 case WASH: /* o: got eob, possibly more output */
4817 FLUSH
4818 if (s->read != s->write)
4819 LEAVE
4820 c->mode = END;
4821 case END:
4822 r = Z_STREAM_END;
4823 LEAVE
4824 case BADCODE: /* x: got error */
4825 r = Z_DATA_ERROR;
4826 LEAVE
4827 default:
4828 r = Z_STREAM_ERROR;
4829 LEAVE
4830 }
4831}
4832
4833
4834void inflate_codes_free(c, z)
4835inflate_codes_statef *c;
4836z_streamp z;
4837{
4838 ZFREE(z, c);
4839 Tracev((stderr, "inflate: codes free\n"));
4840}
4841/* --- infcodes.c */
4842
4843/* +++ infutil.c */
4844/* inflate_util.c -- data and routines common to blocks and codes
4845 * Copyright (C) 1995-1996 Mark Adler
4846 * For conditions of distribution and use, see copyright notice in zlib.h
4847 */
4848
4849/* #include "zutil.h" */
4850/* #include "infblock.h" */
4851/* #include "inftrees.h" */
4852/* #include "infcodes.h" */
4853/* #include "infutil.h" */
4854
4855#ifndef NO_DUMMY_DECL
4856struct inflate_codes_state {int dummy;}; /* for buggy compilers */
4857#endif
4858
4859/* And'ing with mask[n] masks the lower n bits */
4860uInt inflate_mask[17] = {
4861 0x0000,
4862 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
4863 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
4864};
4865
4866
4867/* copy as much as possible from the sliding window to the output area */
4868int inflate_flush(s, z, r)
4869inflate_blocks_statef *s;
4870z_streamp z;
4871int r;
4872{
4873 uInt n;
4874 Bytef *p;
4875 Bytef *q;
4876
4877 /* local copies of source and destination pointers */
4878 p = z->next_out;
4879 q = s->read;
4880
4881 /* compute number of bytes to copy as far as end of window */
4882 n = (uInt)((q <= s->write ? s->write : s->end) - q);
4883 if (n > z->avail_out) n = z->avail_out;
4884 if (n && r == Z_BUF_ERROR) r = Z_OK;
4885
4886 /* update counters */
4887 z->avail_out -= n;
4888 z->total_out += n;
4889
4890 /* update check information */
4891 if (s->checkfn != Z_NULL)
4892 z->adler = s->check = (*s->checkfn)(s->check, q, n);
4893
4894 /* copy as far as end of window */
4895 if (p != Z_NULL) {
4896 zmemcpy(p, q, n);
4897 p += n;
4898 }
4899 q += n;
4900
4901 /* see if more to copy at beginning of window */
4902 if (q == s->end)
4903 {
4904 /* wrap pointers */
4905 q = s->window;
4906 if (s->write == s->end)
4907 s->write = s->window;
4908
4909 /* compute bytes to copy */
4910 n = (uInt)(s->write - q);
4911 if (n > z->avail_out) n = z->avail_out;
4912 if (n && r == Z_BUF_ERROR) r = Z_OK;
4913
4914 /* update counters */
4915 z->avail_out -= n;
4916 z->total_out += n;
4917
4918 /* update check information */
4919 if (s->checkfn != Z_NULL)
4920 z->adler = s->check = (*s->checkfn)(s->check, q, n);
4921
4922 /* copy */
4923 if (p != Z_NULL) {
4924 zmemcpy(p, q, n);
4925 p += n;
4926 }
4927 q += n;
4928 }
4929
4930 /* update pointers */
4931 z->next_out = p;
4932 s->read = q;
4933
4934 /* done */
4935 return r;
4936}
4937/* --- infutil.c */
4938
4939/* +++ inffast.c */
4940/* inffast.c -- process literals and length/distance pairs fast
4941 * Copyright (C) 1995-1996 Mark Adler
4942 * For conditions of distribution and use, see copyright notice in zlib.h
4943 */
4944
4945/* #include "zutil.h" */
4946/* #include "inftrees.h" */
4947/* #include "infblock.h" */
4948/* #include "infcodes.h" */
4949/* #include "infutil.h" */
4950/* #include "inffast.h" */
4951
4952#ifndef NO_DUMMY_DECL
4953struct inflate_codes_state {int dummy;}; /* for buggy compilers */
4954#endif
4955
4956/* simplify the use of the inflate_huft type with some defines */
4957#define base more.Base
4958#define next more.Next
4959#define exop word.what.Exop
4960#define bits word.what.Bits
4961
4962/* macros for bit input with no checking and for returning unused bytes */
4963#define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}}
4964#define UNGRAB {n+=(c=k>>3);p-=c;k&=7;}
4965
4966/* Called with number of bytes left to write in window at least 258
4967 (the maximum string length) and number of input bytes available
4968 at least ten. The ten bytes are six bytes for the longest length/
4969 distance pair plus four bytes for overloading the bit buffer. */
4970
4971int inflate_fast(bl, bd, tl, td, s, z)
4972uInt bl, bd;
4973inflate_huft *tl;
4974inflate_huft *td; /* need separate declaration for Borland C++ */
4975inflate_blocks_statef *s;
4976z_streamp z;
4977{
4978 inflate_huft *t; /* temporary pointer */
4979 uInt e; /* extra bits or operation */
4980 uLong b; /* bit buffer */
4981 uInt k; /* bits in bit buffer */
4982 Bytef *p; /* input data pointer */
4983 uInt n; /* bytes available there */
4984 Bytef *q; /* output window write pointer */
4985 uInt m; /* bytes to end of window or read pointer */
4986 uInt ml; /* mask for literal/length tree */
4987 uInt md; /* mask for distance tree */
4988 uInt c; /* bytes to copy */
4989 uInt d; /* distance back to copy from */
4990 Bytef *r; /* copy source pointer */
4991
4992 /* load input, output, bit values */
4993 LOAD
4994
4995 /* initialize masks */
4996 ml = inflate_mask[bl];
4997 md = inflate_mask[bd];
4998
4999 /* do until not enough input or output space for fast loop */
5000 do { /* assume called with m >= 258 && n >= 10 */
5001 /* get literal/length code */
5002 GRABBITS(20) /* max bits for literal/length code */
5003 if ((e = (t = tl + ((uInt)b & ml))->exop) == 0)
5004 {
5005 DUMPBITS(t->bits)
5006 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5007 "inflate: * literal '%c'\n" :
5008 "inflate: * literal 0x%02x\n", t->base));
5009 *q++ = (Byte)t->base;
5010 m--;
5011 continue;
5012 }
5013 do {
5014 DUMPBITS(t->bits)
5015 if (e & 16)
5016 {
5017 /* get extra bits for length */
5018 e &= 15;
5019 c = t->base + ((uInt)b & inflate_mask[e]);
5020 DUMPBITS(e)
5021 Tracevv((stderr, "inflate: * length %u\n", c));
5022
5023 /* decode distance base of block to copy */
5024 GRABBITS(15); /* max bits for distance code */
5025 e = (t = td + ((uInt)b & md))->exop;
5026 do {
5027 DUMPBITS(t->bits)
5028 if (e & 16)
5029 {
5030 /* get extra bits to add to distance base */
5031 e &= 15;
5032 GRABBITS(e) /* get extra bits (up to 13) */
5033 d = t->base + ((uInt)b & inflate_mask[e]);
5034 DUMPBITS(e)
5035 Tracevv((stderr, "inflate: * distance %u\n", d));
5036
5037 /* do the copy */
5038 m -= c;
5039 if ((uInt)(q - s->window) >= d) /* offset before dest */
5040 { /* just copy */
5041 r = q - d;
5042 *q++ = *r++; c--; /* minimum count is three, */
5043 *q++ = *r++; c--; /* so unroll loop a little */
5044 }
5045 else /* else offset after destination */
5046 {
5047 e = d - (uInt)(q - s->window); /* bytes from offset to end */
5048 r = s->end - e; /* pointer to offset */
5049 if (c > e) /* if source crosses, */
5050 {
5051 c -= e; /* copy to end of window */
5052 do {
5053 *q++ = *r++;
5054 } while (--e);
5055 r = s->window; /* copy rest from start of window */
5056 }
5057 }
5058 do { /* copy all or what's left */
5059 *q++ = *r++;
5060 } while (--c);
5061 break;
5062 }
5063 else if ((e & 64) == 0)
5064 e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop;
5065 else
5066 {
5067 z->msg = (char*)"invalid distance code";
5068 UNGRAB
5069 UPDATE
5070 return Z_DATA_ERROR;
5071 }
5072 } while (1);
5073 break;
5074 }
5075 if ((e & 64) == 0)
5076 {
5077 if ((e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop) == 0)
5078 {
5079 DUMPBITS(t->bits)
5080 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5081 "inflate: * literal '%c'\n" :
5082 "inflate: * literal 0x%02x\n", t->base));
5083 *q++ = (Byte)t->base;
5084 m--;
5085 break;
5086 }
5087 }
5088 else if (e & 32)
5089 {
5090 Tracevv((stderr, "inflate: * end of block\n"));
5091 UNGRAB
5092 UPDATE
5093 return Z_STREAM_END;
5094 }
5095 else
5096 {
5097 z->msg = (char*)"invalid literal/length code";
5098 UNGRAB
5099 UPDATE
5100 return Z_DATA_ERROR;
5101 }
5102 } while (1);
5103 } while (m >= 258 && n >= 10);
5104
5105 /* not enough input or output--restore pointers and return */
5106 UNGRAB
5107 UPDATE
5108 return Z_OK;
5109}
5110/* --- inffast.c */
5111
5112/* +++ zutil.c */
5113/* zutil.c -- target dependent utility functions for the compression library
5114 * Copyright (C) 1995-1996 Jean-loup Gailly.
5115 * For conditions of distribution and use, see copyright notice in zlib.h
5116 */
5117
5118/* From: zutil.c,v 1.17 1996/07/24 13:41:12 me Exp $ */
5119
5120#ifdef DEBUG_ZLIB
5121#include <stdio.h>
5122#endif
5123
5124/* #include "zutil.h" */
5125
5126#ifndef NO_DUMMY_DECL
5127struct internal_state {int dummy;}; /* for buggy compilers */
5128#endif
5129
5130#ifndef STDC
5131extern void exit OF((int));
5132#endif
5133
5134static const char *z_errmsg[10] = {
5135"need dictionary", /* Z_NEED_DICT 2 */
5136"stream end", /* Z_STREAM_END 1 */
5137"", /* Z_OK 0 */
5138"file error", /* Z_ERRNO (-1) */
5139"stream error", /* Z_STREAM_ERROR (-2) */
5140"data error", /* Z_DATA_ERROR (-3) */
5141"insufficient memory", /* Z_MEM_ERROR (-4) */
5142"buffer error", /* Z_BUF_ERROR (-5) */
5143"incompatible version",/* Z_VERSION_ERROR (-6) */
5144""};
5145
5146
5147const char *zlibVersion()
5148{
5149 return ZLIB_VERSION;
5150}
5151
5152#ifdef DEBUG_ZLIB
5153void z_error (m)
5154 char *m;
5155{
5156 fprintf(stderr, "%s\n", m);
5157 exit(1);
5158}
5159#endif
5160
5161#ifndef HAVE_MEMCPY
5162
5163void zmemcpy(dest, source, len)
5164 Bytef* dest;
5165 Bytef* source;
5166 uInt len;
5167{
5168 if (len == 0) return;
5169 do {
5170 *dest++ = *source++; /* ??? to be unrolled */
5171 } while (--len != 0);
5172}
5173
5174int zmemcmp(s1, s2, len)
5175 Bytef* s1;
5176 Bytef* s2;
5177 uInt len;
5178{
5179 uInt j;
5180
5181 for (j = 0; j < len; j++) {
5182 if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1;
5183 }
5184 return 0;
5185}
5186
5187void zmemzero(dest, len)
5188 Bytef* dest;
5189 uInt len;
5190{
5191 if (len == 0) return;
5192 do {
5193 *dest++ = 0; /* ??? to be unrolled */
5194 } while (--len != 0);
5195}
5196#endif
5197
5198#ifdef __TURBOC__
5199#if (defined( __BORLANDC__) || !defined(SMALL_MEDIUM)) && !defined(__32BIT__)
5200/* Small and medium model in Turbo C are for now limited to near allocation
5201 * with reduced MAX_WBITS and MAX_MEM_LEVEL
5202 */
5203# define MY_ZCALLOC
5204
5205/* Turbo C malloc() does not allow dynamic allocation of 64K bytes
5206 * and farmalloc(64K) returns a pointer with an offset of 8, so we
5207 * must fix the pointer. Warning: the pointer must be put back to its
5208 * original form in order to free it, use zcfree().
5209 */
5210
5211#define MAX_PTR 10
5212/* 10*64K = 640K */
5213
5214local int next_ptr = 0;
5215
5216typedef struct ptr_table_s {
5217 voidpf org_ptr;
5218 voidpf new_ptr;
5219} ptr_table;
5220
5221local ptr_table table[MAX_PTR];
5222/* This table is used to remember the original form of pointers
5223 * to large buffers (64K). Such pointers are normalized with a zero offset.
5224 * Since MSDOS is not a preemptive multitasking OS, this table is not
5225 * protected from concurrent access. This hack doesn't work anyway on
5226 * a protected system like OS/2. Use Microsoft C instead.
5227 */
5228
5229voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
5230{
5231 voidpf buf = opaque; /* just to make some compilers happy */
5232 ulg bsize = (ulg)items*size;
5233
5234 /* If we allocate less than 65520 bytes, we assume that farmalloc
5235 * will return a usable pointer which doesn't have to be normalized.
5236 */
5237 if (bsize < 65520L) {
5238 buf = farmalloc(bsize);
5239 if (*(ush*)&buf != 0) return buf;
5240 } else {
5241 buf = farmalloc(bsize + 16L);
5242 }
5243 if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
5244 table[next_ptr].org_ptr = buf;
5245
5246 /* Normalize the pointer to seg:0 */
5247 *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
5248 *(ush*)&buf = 0;
5249 table[next_ptr++].new_ptr = buf;
5250 return buf;
5251}
5252
5253void zcfree (voidpf opaque, voidpf ptr)
5254{
5255 int n;
5256 if (*(ush*)&ptr != 0) { /* object < 64K */
5257 farfree(ptr);
5258 return;
5259 }
5260 /* Find the original pointer */
5261 for (n = 0; n < next_ptr; n++) {
5262 if (ptr != table[n].new_ptr) continue;
5263
5264 farfree(table[n].org_ptr);
5265 while (++n < next_ptr) {
5266 table[n-1] = table[n];
5267 }
5268 next_ptr--;
5269 return;
5270 }
5271 ptr = opaque; /* just to make some compilers happy */
5272 Assert(0, "zcfree: ptr not found");
5273}
5274#endif
5275#endif /* __TURBOC__ */
5276
5277
5278#if defined(M_I86) && !defined(__32BIT__)
5279/* Microsoft C in 16-bit mode */
5280
5281# define MY_ZCALLOC
5282
5283#if (!defined(_MSC_VER) || (_MSC_VER < 600))
5284# define _halloc halloc
5285# define _hfree hfree
5286#endif
5287
5288voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
5289{
5290 if (opaque) opaque = 0; /* to make compiler happy */
5291 return _halloc((long)items, size);
5292}
5293
5294void zcfree (voidpf opaque, voidpf ptr)
5295{
5296 if (opaque) opaque = 0; /* to make compiler happy */
5297 _hfree(ptr);
5298}
5299
5300#endif /* MSC */
5301
5302
5303#ifndef MY_ZCALLOC /* Any system without a special alloc function */
5304
5305#ifndef STDC
5306extern voidp calloc OF((uInt items, uInt size));
5307extern void free OF((voidpf ptr));
5308#endif
5309
5310voidpf zcalloc (opaque, items, size)
5311 voidpf opaque;
5312 unsigned items;
5313 unsigned size;
5314{
5315 if (opaque) items += size - size; /* make compiler happy */
5316 return (voidpf)calloc(items, size);
5317}
5318
5319void zcfree (opaque, ptr)
5320 voidpf opaque;
5321 voidpf ptr;
5322{
5323 free(ptr);
5324 if (opaque) return; /* make compiler happy */
5325}
5326
5327#endif /* MY_ZCALLOC */
5328/* --- zutil.c */
5329
5330/* +++ adler32.c */
5331/* adler32.c -- compute the Adler-32 checksum of a data stream
5332 * Copyright (C) 1995-1996 Mark Adler
5333 * For conditions of distribution and use, see copyright notice in zlib.h
5334 */
5335
5336/* From: adler32.c,v 1.10 1996/05/22 11:52:18 me Exp $ */
5337
5338/* #include "zlib.h" */
5339
5340#define BASE 65521L /* largest prime smaller than 65536 */
5341#define NMAX 5552
5342/* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
5343
5344#define DO1(buf,i) {s1 += buf[i]; s2 += s1;}
5345#define DO2(buf,i) DO1(buf,i); DO1(buf,i+1);
5346#define DO4(buf,i) DO2(buf,i); DO2(buf,i+2);
5347#define DO8(buf,i) DO4(buf,i); DO4(buf,i+4);
5348#define DO16(buf) DO8(buf,0); DO8(buf,8);
5349
5350/* ========================================================================= */
5351uLong adler32(adler, buf, len)
5352 uLong adler;
5353 const Bytef *buf;
5354 uInt len;
5355{
5356 unsigned long s1 = adler & 0xffff;
5357 unsigned long s2 = (adler >> 16) & 0xffff;
5358 int k;
5359
5360 if (buf == Z_NULL) return 1L;
5361
5362 while (len > 0) {
5363 k = len < NMAX ? len : NMAX;
5364 len -= k;
5365 while (k >= 16) {
5366 DO16(buf);
5367 buf += 16;
5368 k -= 16;
5369 }
5370 if (k != 0) do {
5371 s1 += *buf++;
5372 s2 += s1;
5373 } while (--k);
5374 s1 %= BASE;
5375 s2 %= BASE;
5376 }
5377 return (s2 << 16) | s1;
5378}
5379/* --- adler32.c */
2 * This file is derived from various .h and .c files from the zlib-1.0.4
3 * distribution by Jean-loup Gailly and Mark Adler, with some additions
4 * by Paul Mackerras to aid in implementing Deflate compression and
5 * decompression for PPP packets. See zlib.h for conditions of
6 * distribution and use.
7 *
8 * Changes that have been made include:
9 * - added Z_PACKET_FLUSH (see zlib.h for details)
10 * - added inflateIncomp and deflateOutputPending
11 * - allow strm->next_out to be NULL, meaning discard the output
12 *
13 * $Id: zlib.c,v 1.6 1998/03/21 20:56:15 peter Exp $
14 */
15
16/*
17 * ==FILEVERSION 971210==
18 *
19 * This marker is used by the Linux installation script to determine
20 * whether an up-to-date version of this file is already installed.
21 */
22
23#define NO_DUMMY_DECL
24#define NO_ZCFUNCS
25#define MY_ZCALLOC
26
27#if defined(__FreeBSD__) && (defined(KERNEL) || defined(_KERNEL))
28#define inflate inflate_ppp /* FreeBSD already has an inflate :-( */
29#endif
30
31
32/* +++ zutil.h */
33/* zutil.h -- internal interface and configuration of the compression library
34 * Copyright (C) 1995-1996 Jean-loup Gailly.
35 * For conditions of distribution and use, see copyright notice in zlib.h
36 */
37
38/* WARNING: this file should *not* be used by applications. It is
39 part of the implementation of the compression library and is
40 subject to change. Applications should only use zlib.h.
41 */
42
43/* From: zutil.h,v 1.16 1996/07/24 13:41:13 me Exp $ */
44
45#ifndef _Z_UTIL_H
46#define _Z_UTIL_H
47
48#ifdef KERNEL
49#include <net/zlib.h>
50#else
51#include "zlib.h"
52#endif
53
54#if defined(KERNEL) || defined(_KERNEL)
55/* Assume this is a *BSD or SVR4 kernel */
56#include <sys/types.h>
57#include <sys/time.h>
58#include <sys/systm.h>
59# define HAVE_MEMCPY
60# define memcpy(d, s, n) bcopy((s), (d), (n))
61# define memset(d, v, n) bzero((d), (n))
62# define memcmp bcmp
63
64#else
65#if defined(__KERNEL__)
66/* Assume this is a Linux kernel */
67#include <linux/string.h>
68#define HAVE_MEMCPY
69
70#else /* not kernel */
71
72#if defined(MSDOS)||defined(VMS)||defined(CRAY)||defined(WIN32)||defined(RISCOS)
73# include <stddef.h>
74# include <errno.h>
75#else
76 extern int errno;
77#endif
78#ifdef STDC
79# include <string.h>
80# include <stdlib.h>
81#endif
82#endif /* __KERNEL__ */
83#endif /* _KERNEL || KERNEL */
84
85#ifndef local
86# define local static
87#endif
88/* compile with -Dlocal if your debugger can't find static symbols */
89
90typedef unsigned char uch;
91typedef uch FAR uchf;
92typedef unsigned short ush;
93typedef ush FAR ushf;
94typedef unsigned long ulg;
95
96extern const char *z_errmsg[10]; /* indexed by 2-zlib_error */
97/* (size given to avoid silly warnings with Visual C++) */
98
99#define ERR_MSG(err) z_errmsg[Z_NEED_DICT-(err)]
100
101#define ERR_RETURN(strm,err) \
102 return (strm->msg = (char*)ERR_MSG(err), (err))
103/* To be used only when the state is known to be valid */
104
105 /* common constants */
106
107#ifndef DEF_WBITS
108# define DEF_WBITS MAX_WBITS
109#endif
110/* default windowBits for decompression. MAX_WBITS is for compression only */
111
112#if MAX_MEM_LEVEL >= 8
113# define DEF_MEM_LEVEL 8
114#else
115# define DEF_MEM_LEVEL MAX_MEM_LEVEL
116#endif
117/* default memLevel */
118
119#define STORED_BLOCK 0
120#define STATIC_TREES 1
121#define DYN_TREES 2
122/* The three kinds of block type */
123
124#define MIN_MATCH 3
125#define MAX_MATCH 258
126/* The minimum and maximum match lengths */
127
128#define PRESET_DICT 0x20 /* preset dictionary flag in zlib header */
129
130 /* target dependencies */
131
132#ifdef MSDOS
133# define OS_CODE 0x00
134# ifdef __TURBOC__
135# include <alloc.h>
136# else /* MSC or DJGPP */
137# include <malloc.h>
138# endif
139#endif
140
141#ifdef OS2
142# define OS_CODE 0x06
143#endif
144
145#ifdef WIN32 /* Window 95 & Windows NT */
146# define OS_CODE 0x0b
147#endif
148
149#if defined(VAXC) || defined(VMS)
150# define OS_CODE 0x02
151# define FOPEN(name, mode) \
152 fopen((name), (mode), "mbc=60", "ctx=stm", "rfm=fix", "mrs=512")
153#endif
154
155#ifdef AMIGA
156# define OS_CODE 0x01
157#endif
158
159#if defined(ATARI) || defined(atarist)
160# define OS_CODE 0x05
161#endif
162
163#ifdef MACOS
164# define OS_CODE 0x07
165#endif
166
167#ifdef __50SERIES /* Prime/PRIMOS */
168# define OS_CODE 0x0F
169#endif
170
171#ifdef TOPS20
172# define OS_CODE 0x0a
173#endif
174
175#if defined(_BEOS_) || defined(RISCOS)
176# define fdopen(fd,mode) NULL /* No fdopen() */
177#endif
178
179 /* Common defaults */
180
181#ifndef OS_CODE
182# define OS_CODE 0x03 /* assume Unix */
183#endif
184
185#ifndef FOPEN
186# define FOPEN(name, mode) fopen((name), (mode))
187#endif
188
189 /* functions */
190
191#ifdef HAVE_STRERROR
192 extern char *strerror OF((int));
193# define zstrerror(errnum) strerror(errnum)
194#else
195# define zstrerror(errnum) ""
196#endif
197
198#if defined(pyr)
199# define NO_MEMCPY
200#endif
201#if (defined(M_I86SM) || defined(M_I86MM)) && !defined(_MSC_VER)
202 /* Use our own functions for small and medium model with MSC <= 5.0.
203 * You may have to use the same strategy for Borland C (untested).
204 */
205# define NO_MEMCPY
206#endif
207#if defined(STDC) && !defined(HAVE_MEMCPY) && !defined(NO_MEMCPY)
208# define HAVE_MEMCPY
209#endif
210#ifdef HAVE_MEMCPY
211# ifdef SMALL_MEDIUM /* MSDOS small or medium model */
212# define zmemcpy _fmemcpy
213# define zmemcmp _fmemcmp
214# define zmemzero(dest, len) _fmemset(dest, 0, len)
215# else
216# define zmemcpy memcpy
217# define zmemcmp memcmp
218# define zmemzero(dest, len) memset(dest, 0, len)
219# endif
220#else
221 extern void zmemcpy OF((Bytef* dest, Bytef* source, uInt len));
222 extern int zmemcmp OF((Bytef* s1, Bytef* s2, uInt len));
223 extern void zmemzero OF((Bytef* dest, uInt len));
224#endif
225
226/* Diagnostic functions */
227#ifdef DEBUG_ZLIB
228# include <stdio.h>
229# ifndef verbose
230# define verbose 0
231# endif
232 extern void z_error OF((char *m));
233# define Assert(cond,msg) {if(!(cond)) z_error(msg);}
234# define Trace(x) fprintf x
235# define Tracev(x) {if (verbose) fprintf x ;}
236# define Tracevv(x) {if (verbose>1) fprintf x ;}
237# define Tracec(c,x) {if (verbose && (c)) fprintf x ;}
238# define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;}
239#else
240# define Assert(cond,msg)
241# define Trace(x)
242# define Tracev(x)
243# define Tracevv(x)
244# define Tracec(c,x)
245# define Tracecv(c,x)
246#endif
247
248
249typedef uLong (*check_func) OF((uLong check, const Bytef *buf, uInt len));
250
251voidpf zcalloc OF((voidpf opaque, unsigned items, unsigned size));
252void zcfree OF((voidpf opaque, voidpf ptr));
253
254#define ZALLOC(strm, items, size) \
255 (*((strm)->zalloc))((strm)->opaque, (items), (size))
256#define ZFREE(strm, addr) (*((strm)->zfree))((strm)->opaque, (voidpf)(addr))
257#define TRY_FREE(s, p) {if (p) ZFREE(s, p);}
258
259#endif /* _Z_UTIL_H */
260/* --- zutil.h */
261
262/* +++ deflate.h */
263/* deflate.h -- internal compression state
264 * Copyright (C) 1995-1996 Jean-loup Gailly
265 * For conditions of distribution and use, see copyright notice in zlib.h
266 */
267
268/* WARNING: this file should *not* be used by applications. It is
269 part of the implementation of the compression library and is
270 subject to change. Applications should only use zlib.h.
271 */
272
273/* From: deflate.h,v 1.10 1996/07/02 12:41:00 me Exp $ */
274
275#ifndef _DEFLATE_H
276#define _DEFLATE_H
277
278/* #include "zutil.h" */
279
280/* ===========================================================================
281 * Internal compression state.
282 */
283
284#define LENGTH_CODES 29
285/* number of length codes, not counting the special END_BLOCK code */
286
287#define LITERALS 256
288/* number of literal bytes 0..255 */
289
290#define L_CODES (LITERALS+1+LENGTH_CODES)
291/* number of Literal or Length codes, including the END_BLOCK code */
292
293#define D_CODES 30
294/* number of distance codes */
295
296#define BL_CODES 19
297/* number of codes used to transfer the bit lengths */
298
299#define HEAP_SIZE (2*L_CODES+1)
300/* maximum heap size */
301
302#define MAX_BITS 15
303/* All codes must not exceed MAX_BITS bits */
304
305#define INIT_STATE 42
306#define BUSY_STATE 113
307#define FINISH_STATE 666
308/* Stream status */
309
310
311/* Data structure describing a single value and its code string. */
312typedef struct ct_data_s {
313 union {
314 ush freq; /* frequency count */
315 ush code; /* bit string */
316 } fc;
317 union {
318 ush dad; /* father node in Huffman tree */
319 ush len; /* length of bit string */
320 } dl;
321} FAR ct_data;
322
323#define Freq fc.freq
324#define Code fc.code
325#define Dad dl.dad
326#define Len dl.len
327
328typedef struct static_tree_desc_s static_tree_desc;
329
330typedef struct tree_desc_s {
331 ct_data *dyn_tree; /* the dynamic tree */
332 int max_code; /* largest code with non zero frequency */
333 static_tree_desc *stat_desc; /* the corresponding static tree */
334} FAR tree_desc;
335
336typedef ush Pos;
337typedef Pos FAR Posf;
338typedef unsigned IPos;
339
340/* A Pos is an index in the character window. We use short instead of int to
341 * save space in the various tables. IPos is used only for parameter passing.
342 */
343
344typedef struct deflate_state {
345 z_streamp strm; /* pointer back to this zlib stream */
346 int status; /* as the name implies */
347 Bytef *pending_buf; /* output still pending */
348 ulg pending_buf_size; /* size of pending_buf */
349 Bytef *pending_out; /* next pending byte to output to the stream */
350 int pending; /* nb of bytes in the pending buffer */
351 int noheader; /* suppress zlib header and adler32 */
352 Byte data_type; /* UNKNOWN, BINARY or ASCII */
353 Byte method; /* STORED (for zip only) or DEFLATED */
354 int last_flush; /* value of flush param for previous deflate call */
355
356 /* used by deflate.c: */
357
358 uInt w_size; /* LZ77 window size (32K by default) */
359 uInt w_bits; /* log2(w_size) (8..16) */
360 uInt w_mask; /* w_size - 1 */
361
362 Bytef *window;
363 /* Sliding window. Input bytes are read into the second half of the window,
364 * and move to the first half later to keep a dictionary of at least wSize
365 * bytes. With this organization, matches are limited to a distance of
366 * wSize-MAX_MATCH bytes, but this ensures that IO is always
367 * performed with a length multiple of the block size. Also, it limits
368 * the window size to 64K, which is quite useful on MSDOS.
369 * To do: use the user input buffer as sliding window.
370 */
371
372 ulg window_size;
373 /* Actual size of window: 2*wSize, except when the user input buffer
374 * is directly used as sliding window.
375 */
376
377 Posf *prev;
378 /* Link to older string with same hash index. To limit the size of this
379 * array to 64K, this link is maintained only for the last 32K strings.
380 * An index in this array is thus a window index modulo 32K.
381 */
382
383 Posf *head; /* Heads of the hash chains or NIL. */
384
385 uInt ins_h; /* hash index of string to be inserted */
386 uInt hash_size; /* number of elements in hash table */
387 uInt hash_bits; /* log2(hash_size) */
388 uInt hash_mask; /* hash_size-1 */
389
390 uInt hash_shift;
391 /* Number of bits by which ins_h must be shifted at each input
392 * step. It must be such that after MIN_MATCH steps, the oldest
393 * byte no longer takes part in the hash key, that is:
394 * hash_shift * MIN_MATCH >= hash_bits
395 */
396
397 long block_start;
398 /* Window position at the beginning of the current output block. Gets
399 * negative when the window is moved backwards.
400 */
401
402 uInt match_length; /* length of best match */
403 IPos prev_match; /* previous match */
404 int match_available; /* set if previous match exists */
405 uInt strstart; /* start of string to insert */
406 uInt match_start; /* start of matching string */
407 uInt lookahead; /* number of valid bytes ahead in window */
408
409 uInt prev_length;
410 /* Length of the best match at previous step. Matches not greater than this
411 * are discarded. This is used in the lazy match evaluation.
412 */
413
414 uInt max_chain_length;
415 /* To speed up deflation, hash chains are never searched beyond this
416 * length. A higher limit improves compression ratio but degrades the
417 * speed.
418 */
419
420 uInt max_lazy_match;
421 /* Attempt to find a better match only when the current match is strictly
422 * smaller than this value. This mechanism is used only for compression
423 * levels >= 4.
424 */
425# define max_insert_length max_lazy_match
426 /* Insert new strings in the hash table only if the match length is not
427 * greater than this length. This saves time but degrades compression.
428 * max_insert_length is used only for compression levels <= 3.
429 */
430
431 int level; /* compression level (1..9) */
432 int strategy; /* favor or force Huffman coding*/
433
434 uInt good_match;
435 /* Use a faster search when the previous match is longer than this */
436
437 int nice_match; /* Stop searching when current match exceeds this */
438
439 /* used by trees.c: */
440 /* Didn't use ct_data typedef below to supress compiler warning */
441 struct ct_data_s dyn_ltree[HEAP_SIZE]; /* literal and length tree */
442 struct ct_data_s dyn_dtree[2*D_CODES+1]; /* distance tree */
443 struct ct_data_s bl_tree[2*BL_CODES+1]; /* Huffman tree for bit lengths */
444
445 struct tree_desc_s l_desc; /* desc. for literal tree */
446 struct tree_desc_s d_desc; /* desc. for distance tree */
447 struct tree_desc_s bl_desc; /* desc. for bit length tree */
448
449 ush bl_count[MAX_BITS+1];
450 /* number of codes at each bit length for an optimal tree */
451
452 int heap[2*L_CODES+1]; /* heap used to build the Huffman trees */
453 int heap_len; /* number of elements in the heap */
454 int heap_max; /* element of largest frequency */
455 /* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used.
456 * The same heap array is used to build all trees.
457 */
458
459 uch depth[2*L_CODES+1];
460 /* Depth of each subtree used as tie breaker for trees of equal frequency
461 */
462
463 uchf *l_buf; /* buffer for literals or lengths */
464
465 uInt lit_bufsize;
466 /* Size of match buffer for literals/lengths. There are 4 reasons for
467 * limiting lit_bufsize to 64K:
468 * - frequencies can be kept in 16 bit counters
469 * - if compression is not successful for the first block, all input
470 * data is still in the window so we can still emit a stored block even
471 * when input comes from standard input. (This can also be done for
472 * all blocks if lit_bufsize is not greater than 32K.)
473 * - if compression is not successful for a file smaller than 64K, we can
474 * even emit a stored file instead of a stored block (saving 5 bytes).
475 * This is applicable only for zip (not gzip or zlib).
476 * - creating new Huffman trees less frequently may not provide fast
477 * adaptation to changes in the input data statistics. (Take for
478 * example a binary file with poorly compressible code followed by
479 * a highly compressible string table.) Smaller buffer sizes give
480 * fast adaptation but have of course the overhead of transmitting
481 * trees more frequently.
482 * - I can't count above 4
483 */
484
485 uInt last_lit; /* running index in l_buf */
486
487 ushf *d_buf;
488 /* Buffer for distances. To simplify the code, d_buf and l_buf have
489 * the same number of elements. To use different lengths, an extra flag
490 * array would be necessary.
491 */
492
493 ulg opt_len; /* bit length of current block with optimal trees */
494 ulg static_len; /* bit length of current block with static trees */
495 ulg compressed_len; /* total bit length of compressed file */
496 uInt matches; /* number of string matches in current block */
497 int last_eob_len; /* bit length of EOB code for last block */
498
499#ifdef DEBUG_ZLIB
500 ulg bits_sent; /* bit length of the compressed data */
501#endif
502
503 ush bi_buf;
504 /* Output buffer. bits are inserted starting at the bottom (least
505 * significant bits).
506 */
507 int bi_valid;
508 /* Number of valid bits in bi_buf. All bits above the last valid bit
509 * are always zero.
510 */
511
512} FAR deflate_state;
513
514/* Output a byte on the stream.
515 * IN assertion: there is enough room in pending_buf.
516 */
517#define put_byte(s, c) {s->pending_buf[s->pending++] = (c);}
518
519
520#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
521/* Minimum amount of lookahead, except at the end of the input file.
522 * See deflate.c for comments about the MIN_MATCH+1.
523 */
524
525#define MAX_DIST(s) ((s)->w_size-MIN_LOOKAHEAD)
526/* In order to simplify the code, particularly on 16 bit machines, match
527 * distances are limited to MAX_DIST instead of WSIZE.
528 */
529
530 /* in trees.c */
531void _tr_init OF((deflate_state *s));
532int _tr_tally OF((deflate_state *s, unsigned dist, unsigned lc));
533ulg _tr_flush_block OF((deflate_state *s, charf *buf, ulg stored_len,
534 int eof));
535void _tr_align OF((deflate_state *s));
536void _tr_stored_block OF((deflate_state *s, charf *buf, ulg stored_len,
537 int eof));
538void _tr_stored_type_only OF((deflate_state *));
539
540#endif
541/* --- deflate.h */
542
543/* +++ deflate.c */
544/* deflate.c -- compress data using the deflation algorithm
545 * Copyright (C) 1995-1996 Jean-loup Gailly.
546 * For conditions of distribution and use, see copyright notice in zlib.h
547 */
548
549/*
550 * ALGORITHM
551 *
552 * The "deflation" process depends on being able to identify portions
553 * of the input text which are identical to earlier input (within a
554 * sliding window trailing behind the input currently being processed).
555 *
556 * The most straightforward technique turns out to be the fastest for
557 * most input files: try all possible matches and select the longest.
558 * The key feature of this algorithm is that insertions into the string
559 * dictionary are very simple and thus fast, and deletions are avoided
560 * completely. Insertions are performed at each input character, whereas
561 * string matches are performed only when the previous match ends. So it
562 * is preferable to spend more time in matches to allow very fast string
563 * insertions and avoid deletions. The matching algorithm for small
564 * strings is inspired from that of Rabin & Karp. A brute force approach
565 * is used to find longer strings when a small match has been found.
566 * A similar algorithm is used in comic (by Jan-Mark Wams) and freeze
567 * (by Leonid Broukhis).
568 * A previous version of this file used a more sophisticated algorithm
569 * (by Fiala and Greene) which is guaranteed to run in linear amortized
570 * time, but has a larger average cost, uses more memory and is patented.
571 * However the F&G algorithm may be faster for some highly redundant
572 * files if the parameter max_chain_length (described below) is too large.
573 *
574 * ACKNOWLEDGEMENTS
575 *
576 * The idea of lazy evaluation of matches is due to Jan-Mark Wams, and
577 * I found it in 'freeze' written by Leonid Broukhis.
578 * Thanks to many people for bug reports and testing.
579 *
580 * REFERENCES
581 *
582 * Deutsch, L.P.,"DEFLATE Compressed Data Format Specification".
583 * Available in ftp://ds.internic.net/rfc/rfc1951.txt
584 *
585 * A description of the Rabin and Karp algorithm is given in the book
586 * "Algorithms" by R. Sedgewick, Addison-Wesley, p252.
587 *
588 * Fiala,E.R., and Greene,D.H.
589 * Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595
590 *
591 */
592
593/* From: deflate.c,v 1.15 1996/07/24 13:40:58 me Exp $ */
594
595/* #include "deflate.h" */
596
597char deflate_copyright[] = " deflate 1.0.4 Copyright 1995-1996 Jean-loup Gailly ";
598/*
599 If you use the zlib library in a product, an acknowledgment is welcome
600 in the documentation of your product. If for some reason you cannot
601 include such an acknowledgment, I would appreciate that you keep this
602 copyright string in the executable of your product.
603 */
604
605/* ===========================================================================
606 * Function prototypes.
607 */
608typedef enum {
609 need_more, /* block not completed, need more input or more output */
610 block_done, /* block flush performed */
611 finish_started, /* finish started, need only more output at next deflate */
612 finish_done /* finish done, accept no more input or output */
613} block_state;
614
615typedef block_state (*compress_func) OF((deflate_state *s, int flush));
616/* Compression function. Returns the block state after the call. */
617
618local void fill_window OF((deflate_state *s));
619local block_state deflate_stored OF((deflate_state *s, int flush));
620local block_state deflate_fast OF((deflate_state *s, int flush));
621local block_state deflate_slow OF((deflate_state *s, int flush));
622local void lm_init OF((deflate_state *s));
623local void putShortMSB OF((deflate_state *s, uInt b));
624local void flush_pending OF((z_streamp strm));
625local int read_buf OF((z_streamp strm, charf *buf, unsigned size));
626#ifdef ASMV
627 void match_init OF((void)); /* asm code initialization */
628 uInt longest_match OF((deflate_state *s, IPos cur_match));
629#else
630local uInt longest_match OF((deflate_state *s, IPos cur_match));
631#endif
632
633#ifdef DEBUG_ZLIB
634local void check_match OF((deflate_state *s, IPos start, IPos match,
635 int length));
636#endif
637
638/* ===========================================================================
639 * Local data
640 */
641
642#define NIL 0
643/* Tail of hash chains */
644
645#ifndef TOO_FAR
646# define TOO_FAR 4096
647#endif
648/* Matches of length 3 are discarded if their distance exceeds TOO_FAR */
649
650#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
651/* Minimum amount of lookahead, except at the end of the input file.
652 * See deflate.c for comments about the MIN_MATCH+1.
653 */
654
655/* Values for max_lazy_match, good_match and max_chain_length, depending on
656 * the desired pack level (0..9). The values given below have been tuned to
657 * exclude worst case performance for pathological files. Better values may be
658 * found for specific files.
659 */
660typedef struct config_s {
661 ush good_length; /* reduce lazy search above this match length */
662 ush max_lazy; /* do not perform lazy search above this match length */
663 ush nice_length; /* quit search above this match length */
664 ush max_chain;
665 compress_func func;
666} config;
667
668local config configuration_table[10] = {
669/* good lazy nice chain */
670/* 0 */ {0, 0, 0, 0, deflate_stored}, /* store only */
671/* 1 */ {4, 4, 8, 4, deflate_fast}, /* maximum speed, no lazy matches */
672/* 2 */ {4, 5, 16, 8, deflate_fast},
673/* 3 */ {4, 6, 32, 32, deflate_fast},
674
675/* 4 */ {4, 4, 16, 16, deflate_slow}, /* lazy matches */
676/* 5 */ {8, 16, 32, 32, deflate_slow},
677/* 6 */ {8, 16, 128, 128, deflate_slow},
678/* 7 */ {8, 32, 128, 256, deflate_slow},
679/* 8 */ {32, 128, 258, 1024, deflate_slow},
680/* 9 */ {32, 258, 258, 4096, deflate_slow}}; /* maximum compression */
681
682/* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4
683 * For deflate_fast() (levels <= 3) good is ignored and lazy has a different
684 * meaning.
685 */
686
687#define EQUAL 0
688/* result of memcmp for equal strings */
689
690#ifndef NO_DUMMY_DECL
691struct static_tree_desc_s {int dummy;}; /* for buggy compilers */
692#endif
693
694/* ===========================================================================
695 * Update a hash value with the given input byte
696 * IN assertion: all calls to to UPDATE_HASH are made with consecutive
697 * input characters, so that a running hash key can be computed from the
698 * previous key instead of complete recalculation each time.
699 */
700#define UPDATE_HASH(s,h,c) (h = (((h)<<s->hash_shift) ^ (c)) & s->hash_mask)
701
702
703/* ===========================================================================
704 * Insert string str in the dictionary and set match_head to the previous head
705 * of the hash chain (the most recent string with same hash key). Return
706 * the previous length of the hash chain.
707 * IN assertion: all calls to to INSERT_STRING are made with consecutive
708 * input characters and the first MIN_MATCH bytes of str are valid
709 * (except for the last MIN_MATCH-1 bytes of the input file).
710 */
711#define INSERT_STRING(s, str, match_head) \
712 (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \
713 s->prev[(str) & s->w_mask] = match_head = s->head[s->ins_h], \
714 s->head[s->ins_h] = (Pos)(str))
715
716/* ===========================================================================
717 * Initialize the hash table (avoiding 64K overflow for 16 bit systems).
718 * prev[] will be initialized on the fly.
719 */
720#define CLEAR_HASH(s) \
721 s->head[s->hash_size-1] = NIL; \
722 zmemzero((charf *)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head));
723
724/* ========================================================================= */
725int deflateInit_(strm, level, version, stream_size)
726 z_streamp strm;
727 int level;
728 const char *version;
729 int stream_size;
730{
731 return deflateInit2_(strm, level, Z_DEFLATED, MAX_WBITS, DEF_MEM_LEVEL,
732 Z_DEFAULT_STRATEGY, version, stream_size);
733 /* To do: ignore strm->next_in if we use it as window */
734}
735
736/* ========================================================================= */
737int deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
738 version, stream_size)
739 z_streamp strm;
740 int level;
741 int method;
742 int windowBits;
743 int memLevel;
744 int strategy;
745 const char *version;
746 int stream_size;
747{
748 deflate_state *s;
749 int noheader = 0;
750 static char* my_version = ZLIB_VERSION;
751
752 ushf *overlay;
753 /* We overlay pending_buf and d_buf+l_buf. This works since the average
754 * output size for (length,distance) codes is <= 24 bits.
755 */
756
757 if (version == Z_NULL || version[0] != my_version[0] ||
758 stream_size != sizeof(z_stream)) {
759 return Z_VERSION_ERROR;
760 }
761 if (strm == Z_NULL) return Z_STREAM_ERROR;
762
763 strm->msg = Z_NULL;
764#ifndef NO_ZCFUNCS
765 if (strm->zalloc == Z_NULL) {
766 strm->zalloc = zcalloc;
767 strm->opaque = (voidpf)0;
768 }
769 if (strm->zfree == Z_NULL) strm->zfree = zcfree;
770#endif
771
772 if (level == Z_DEFAULT_COMPRESSION) level = 6;
773
774 if (windowBits < 0) { /* undocumented feature: suppress zlib header */
775 noheader = 1;
776 windowBits = -windowBits;
777 }
778 if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED ||
779 windowBits < 8 || windowBits > 15 || level < 0 || level > 9 ||
780 strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
781 return Z_STREAM_ERROR;
782 }
783 s = (deflate_state *) ZALLOC(strm, 1, sizeof(deflate_state));
784 if (s == Z_NULL) return Z_MEM_ERROR;
785 strm->state = (struct internal_state FAR *)s;
786 s->strm = strm;
787
788 s->noheader = noheader;
789 s->w_bits = windowBits;
790 s->w_size = 1 << s->w_bits;
791 s->w_mask = s->w_size - 1;
792
793 s->hash_bits = memLevel + 7;
794 s->hash_size = 1 << s->hash_bits;
795 s->hash_mask = s->hash_size - 1;
796 s->hash_shift = ((s->hash_bits+MIN_MATCH-1)/MIN_MATCH);
797
798 s->window = (Bytef *) ZALLOC(strm, s->w_size, 2*sizeof(Byte));
799 s->prev = (Posf *) ZALLOC(strm, s->w_size, sizeof(Pos));
800 s->head = (Posf *) ZALLOC(strm, s->hash_size, sizeof(Pos));
801
802 s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */
803
804 overlay = (ushf *) ZALLOC(strm, s->lit_bufsize, sizeof(ush)+2);
805 s->pending_buf = (uchf *) overlay;
806 s->pending_buf_size = (ulg)s->lit_bufsize * (sizeof(ush)+2L);
807
808 if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL ||
809 s->pending_buf == Z_NULL) {
810 strm->msg = (char*)ERR_MSG(Z_MEM_ERROR);
811 deflateEnd (strm);
812 return Z_MEM_ERROR;
813 }
814 s->d_buf = overlay + s->lit_bufsize/sizeof(ush);
815 s->l_buf = s->pending_buf + (1+sizeof(ush))*s->lit_bufsize;
816
817 s->level = level;
818 s->strategy = strategy;
819 s->method = (Byte)method;
820
821 return deflateReset(strm);
822}
823
824/* ========================================================================= */
825int deflateSetDictionary (strm, dictionary, dictLength)
826 z_streamp strm;
827 const Bytef *dictionary;
828 uInt dictLength;
829{
830 deflate_state *s;
831 uInt length = dictLength;
832 uInt n;
833 IPos hash_head = 0;
834
835 if (strm == Z_NULL || strm->state == Z_NULL || dictionary == Z_NULL)
836 return Z_STREAM_ERROR;
837
838 s = (deflate_state *) strm->state;
839 if (s->status != INIT_STATE) return Z_STREAM_ERROR;
840
841 strm->adler = adler32(strm->adler, dictionary, dictLength);
842
843 if (length < MIN_MATCH) return Z_OK;
844 if (length > MAX_DIST(s)) {
845 length = MAX_DIST(s);
846#ifndef USE_DICT_HEAD
847 dictionary += dictLength - length; /* use the tail of the dictionary */
848#endif
849 }
850 zmemcpy((charf *)s->window, dictionary, length);
851 s->strstart = length;
852 s->block_start = (long)length;
853
854 /* Insert all strings in the hash table (except for the last two bytes).
855 * s->lookahead stays null, so s->ins_h will be recomputed at the next
856 * call of fill_window.
857 */
858 s->ins_h = s->window[0];
859 UPDATE_HASH(s, s->ins_h, s->window[1]);
860 for (n = 0; n <= length - MIN_MATCH; n++) {
861 INSERT_STRING(s, n, hash_head);
862 }
863 if (hash_head) hash_head = 0; /* to make compiler happy */
864 return Z_OK;
865}
866
867/* ========================================================================= */
868int deflateReset (strm)
869 z_streamp strm;
870{
871 deflate_state *s;
872
873 if (strm == Z_NULL || strm->state == Z_NULL ||
874 strm->zalloc == Z_NULL || strm->zfree == Z_NULL) return Z_STREAM_ERROR;
875
876 strm->total_in = strm->total_out = 0;
877 strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */
878 strm->data_type = Z_UNKNOWN;
879
880 s = (deflate_state *)strm->state;
881 s->pending = 0;
882 s->pending_out = s->pending_buf;
883
884 if (s->noheader < 0) {
885 s->noheader = 0; /* was set to -1 by deflate(..., Z_FINISH); */
886 }
887 s->status = s->noheader ? BUSY_STATE : INIT_STATE;
888 strm->adler = 1;
889 s->last_flush = Z_NO_FLUSH;
890
891 _tr_init(s);
892 lm_init(s);
893
894 return Z_OK;
895}
896
897/* ========================================================================= */
898int deflateParams(strm, level, strategy)
899 z_streamp strm;
900 int level;
901 int strategy;
902{
903 deflate_state *s;
904 compress_func func;
905 int err = Z_OK;
906
907 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
908 s = (deflate_state *) strm->state;
909
910 if (level == Z_DEFAULT_COMPRESSION) {
911 level = 6;
912 }
913 if (level < 0 || level > 9 || strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
914 return Z_STREAM_ERROR;
915 }
916 func = configuration_table[s->level].func;
917
918 if (func != configuration_table[level].func && strm->total_in != 0) {
919 /* Flush the last buffer: */
920 err = deflate(strm, Z_PARTIAL_FLUSH);
921 }
922 if (s->level != level) {
923 s->level = level;
924 s->max_lazy_match = configuration_table[level].max_lazy;
925 s->good_match = configuration_table[level].good_length;
926 s->nice_match = configuration_table[level].nice_length;
927 s->max_chain_length = configuration_table[level].max_chain;
928 }
929 s->strategy = strategy;
930 return err;
931}
932
933/* =========================================================================
934 * Put a short in the pending buffer. The 16-bit value is put in MSB order.
935 * IN assertion: the stream state is correct and there is enough room in
936 * pending_buf.
937 */
938local void putShortMSB (s, b)
939 deflate_state *s;
940 uInt b;
941{
942 put_byte(s, (Byte)(b >> 8));
943 put_byte(s, (Byte)(b & 0xff));
944}
945
946/* =========================================================================
947 * Flush as much pending output as possible. All deflate() output goes
948 * through this function so some applications may wish to modify it
949 * to avoid allocating a large strm->next_out buffer and copying into it.
950 * (See also read_buf()).
951 */
952local void flush_pending(strm)
953 z_streamp strm;
954{
955 deflate_state *s = (deflate_state *) strm->state;
956 unsigned len = s->pending;
957
958 if (len > strm->avail_out) len = strm->avail_out;
959 if (len == 0) return;
960
961 if (strm->next_out != Z_NULL) {
962 zmemcpy(strm->next_out, s->pending_out, len);
963 strm->next_out += len;
964 }
965 s->pending_out += len;
966 strm->total_out += len;
967 strm->avail_out -= len;
968 s->pending -= len;
969 if (s->pending == 0) {
970 s->pending_out = s->pending_buf;
971 }
972}
973
974/* ========================================================================= */
975int deflate (strm, flush)
976 z_streamp strm;
977 int flush;
978{
979 int old_flush; /* value of flush param for previous deflate call */
980 deflate_state *s;
981
982 if (strm == Z_NULL || strm->state == Z_NULL ||
983 flush > Z_FINISH || flush < 0) {
984 return Z_STREAM_ERROR;
985 }
986 s = (deflate_state *) strm->state;
987
988 if ((strm->next_in == Z_NULL && strm->avail_in != 0) ||
989 (s->status == FINISH_STATE && flush != Z_FINISH)) {
990 ERR_RETURN(strm, Z_STREAM_ERROR);
991 }
992 if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR);
993
994 s->strm = strm; /* just in case */
995 old_flush = s->last_flush;
996 s->last_flush = flush;
997
998 /* Write the zlib header */
999 if (s->status == INIT_STATE) {
1000
1001 uInt header = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8;
1002 uInt level_flags = (s->level-1) >> 1;
1003
1004 if (level_flags > 3) level_flags = 3;
1005 header |= (level_flags << 6);
1006 if (s->strstart != 0) header |= PRESET_DICT;
1007 header += 31 - (header % 31);
1008
1009 s->status = BUSY_STATE;
1010 putShortMSB(s, header);
1011
1012 /* Save the adler32 of the preset dictionary: */
1013 if (s->strstart != 0) {
1014 putShortMSB(s, (uInt)(strm->adler >> 16));
1015 putShortMSB(s, (uInt)(strm->adler & 0xffff));
1016 }
1017 strm->adler = 1L;
1018 }
1019
1020 /* Flush as much pending output as possible */
1021 if (s->pending != 0) {
1022 flush_pending(strm);
1023 if (strm->avail_out == 0) {
1024 /* Since avail_out is 0, deflate will be called again with
1025 * more output space, but possibly with both pending and
1026 * avail_in equal to zero. There won't be anything to do,
1027 * but this is not an error situation so make sure we
1028 * return OK instead of BUF_ERROR at next call of deflate:
1029 */
1030 s->last_flush = -1;
1031 return Z_OK;
1032 }
1033
1034 /* Make sure there is something to do and avoid duplicate consecutive
1035 * flushes. For repeated and useless calls with Z_FINISH, we keep
1036 * returning Z_STREAM_END instead of Z_BUFF_ERROR.
1037 */
1038 } else if (strm->avail_in == 0 && flush <= old_flush &&
1039 flush != Z_FINISH) {
1040 ERR_RETURN(strm, Z_BUF_ERROR);
1041 }
1042
1043 /* User must not provide more input after the first FINISH: */
1044 if (s->status == FINISH_STATE && strm->avail_in != 0) {
1045 ERR_RETURN(strm, Z_BUF_ERROR);
1046 }
1047
1048 /* Start a new block or continue the current one.
1049 */
1050 if (strm->avail_in != 0 || s->lookahead != 0 ||
1051 (flush != Z_NO_FLUSH && s->status != FINISH_STATE)) {
1052 block_state bstate;
1053
1054 bstate = (*(configuration_table[s->level].func))(s, flush);
1055
1056 if (bstate == finish_started || bstate == finish_done) {
1057 s->status = FINISH_STATE;
1058 }
1059 if (bstate == need_more || bstate == finish_started) {
1060 if (strm->avail_out == 0) {
1061 s->last_flush = -1; /* avoid BUF_ERROR next call, see above */
1062 }
1063 return Z_OK;
1064 /* If flush != Z_NO_FLUSH && avail_out == 0, the next call
1065 * of deflate should use the same flush parameter to make sure
1066 * that the flush is complete. So we don't have to output an
1067 * empty block here, this will be done at next call. This also
1068 * ensures that for a very small output buffer, we emit at most
1069 * one empty block.
1070 */
1071 }
1072 if (bstate == block_done) {
1073 if (flush == Z_PARTIAL_FLUSH) {
1074 _tr_align(s);
1075 } else if (flush == Z_PACKET_FLUSH) {
1076 /* Output just the 3-bit `stored' block type value,
1077 but not a zero length. */
1078 _tr_stored_type_only(s);
1079 } else { /* FULL_FLUSH or SYNC_FLUSH */
1080 _tr_stored_block(s, (char*)0, 0L, 0);
1081 /* For a full flush, this empty block will be recognized
1082 * as a special marker by inflate_sync().
1083 */
1084 if (flush == Z_FULL_FLUSH) {
1085 CLEAR_HASH(s); /* forget history */
1086 }
1087 }
1088 flush_pending(strm);
1089 if (strm->avail_out == 0) {
1090 s->last_flush = -1; /* avoid BUF_ERROR at next call, see above */
1091 return Z_OK;
1092 }
1093 }
1094 }
1095 Assert(strm->avail_out > 0, "bug2");
1096
1097 if (flush != Z_FINISH) return Z_OK;
1098 if (s->noheader) return Z_STREAM_END;
1099
1100 /* Write the zlib trailer (adler32) */
1101 putShortMSB(s, (uInt)(strm->adler >> 16));
1102 putShortMSB(s, (uInt)(strm->adler & 0xffff));
1103 flush_pending(strm);
1104 /* If avail_out is zero, the application will call deflate again
1105 * to flush the rest.
1106 */
1107 s->noheader = -1; /* write the trailer only once! */
1108 return s->pending != 0 ? Z_OK : Z_STREAM_END;
1109}
1110
1111/* ========================================================================= */
1112int deflateEnd (strm)
1113 z_streamp strm;
1114{
1115 int status;
1116 deflate_state *s;
1117
1118 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
1119 s = (deflate_state *) strm->state;
1120
1121 status = s->status;
1122 if (status != INIT_STATE && status != BUSY_STATE &&
1123 status != FINISH_STATE) {
1124 return Z_STREAM_ERROR;
1125 }
1126
1127 /* Deallocate in reverse order of allocations: */
1128 TRY_FREE(strm, s->pending_buf);
1129 TRY_FREE(strm, s->head);
1130 TRY_FREE(strm, s->prev);
1131 TRY_FREE(strm, s->window);
1132
1133 ZFREE(strm, s);
1134 strm->state = Z_NULL;
1135
1136 return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK;
1137}
1138
1139/* =========================================================================
1140 * Copy the source state to the destination state.
1141 */
1142int deflateCopy (dest, source)
1143 z_streamp dest;
1144 z_streamp source;
1145{
1146 deflate_state *ds;
1147 deflate_state *ss;
1148 ushf *overlay;
1149
1150 if (source == Z_NULL || dest == Z_NULL || source->state == Z_NULL)
1151 return Z_STREAM_ERROR;
1152 ss = (deflate_state *) source->state;
1153
1154 zmemcpy(dest, source, sizeof(*dest));
1155
1156 ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state));
1157 if (ds == Z_NULL) return Z_MEM_ERROR;
1158 dest->state = (struct internal_state FAR *) ds;
1159 zmemcpy(ds, ss, sizeof(*ds));
1160 ds->strm = dest;
1161
1162 ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte));
1163 ds->prev = (Posf *) ZALLOC(dest, ds->w_size, sizeof(Pos));
1164 ds->head = (Posf *) ZALLOC(dest, ds->hash_size, sizeof(Pos));
1165 overlay = (ushf *) ZALLOC(dest, ds->lit_bufsize, sizeof(ush)+2);
1166 ds->pending_buf = (uchf *) overlay;
1167
1168 if (ds->window == Z_NULL || ds->prev == Z_NULL || ds->head == Z_NULL ||
1169 ds->pending_buf == Z_NULL) {
1170 deflateEnd (dest);
1171 return Z_MEM_ERROR;
1172 }
1173 /* ??? following zmemcpy doesn't work for 16-bit MSDOS */
1174 zmemcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte));
1175 zmemcpy(ds->prev, ss->prev, ds->w_size * sizeof(Pos));
1176 zmemcpy(ds->head, ss->head, ds->hash_size * sizeof(Pos));
1177 zmemcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size);
1178
1179 ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf);
1180 ds->d_buf = overlay + ds->lit_bufsize/sizeof(ush);
1181 ds->l_buf = ds->pending_buf + (1+sizeof(ush))*ds->lit_bufsize;
1182
1183 ds->l_desc.dyn_tree = ds->dyn_ltree;
1184 ds->d_desc.dyn_tree = ds->dyn_dtree;
1185 ds->bl_desc.dyn_tree = ds->bl_tree;
1186
1187 return Z_OK;
1188}
1189
1190/* ===========================================================================
1191 * Return the number of bytes of output which are immediately available
1192 * for output from the decompressor.
1193 */
1194int deflateOutputPending (strm)
1195 z_streamp strm;
1196{
1197 if (strm == Z_NULL || strm->state == Z_NULL) return 0;
1198
1199 return ((deflate_state *)(strm->state))->pending;
1200}
1201
1202/* ===========================================================================
1203 * Read a new buffer from the current input stream, update the adler32
1204 * and total number of bytes read. All deflate() input goes through
1205 * this function so some applications may wish to modify it to avoid
1206 * allocating a large strm->next_in buffer and copying from it.
1207 * (See also flush_pending()).
1208 */
1209local int read_buf(strm, buf, size)
1210 z_streamp strm;
1211 charf *buf;
1212 unsigned size;
1213{
1214 unsigned len = strm->avail_in;
1215
1216 if (len > size) len = size;
1217 if (len == 0) return 0;
1218
1219 strm->avail_in -= len;
1220
1221 if (!((deflate_state *)(strm->state))->noheader) {
1222 strm->adler = adler32(strm->adler, strm->next_in, len);
1223 }
1224 zmemcpy(buf, strm->next_in, len);
1225 strm->next_in += len;
1226 strm->total_in += len;
1227
1228 return (int)len;
1229}
1230
1231/* ===========================================================================
1232 * Initialize the "longest match" routines for a new zlib stream
1233 */
1234local void lm_init (s)
1235 deflate_state *s;
1236{
1237 s->window_size = (ulg)2L*s->w_size;
1238
1239 CLEAR_HASH(s);
1240
1241 /* Set the default configuration parameters:
1242 */
1243 s->max_lazy_match = configuration_table[s->level].max_lazy;
1244 s->good_match = configuration_table[s->level].good_length;
1245 s->nice_match = configuration_table[s->level].nice_length;
1246 s->max_chain_length = configuration_table[s->level].max_chain;
1247
1248 s->strstart = 0;
1249 s->block_start = 0L;
1250 s->lookahead = 0;
1251 s->match_length = s->prev_length = MIN_MATCH-1;
1252 s->match_available = 0;
1253 s->ins_h = 0;
1254#ifdef ASMV
1255 match_init(); /* initialize the asm code */
1256#endif
1257}
1258
1259/* ===========================================================================
1260 * Set match_start to the longest match starting at the given string and
1261 * return its length. Matches shorter or equal to prev_length are discarded,
1262 * in which case the result is equal to prev_length and match_start is
1263 * garbage.
1264 * IN assertions: cur_match is the head of the hash chain for the current
1265 * string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1
1266 * OUT assertion: the match length is not greater than s->lookahead.
1267 */
1268#ifndef ASMV
1269/* For 80x86 and 680x0, an optimized version will be provided in match.asm or
1270 * match.S. The code will be functionally equivalent.
1271 */
1272local uInt longest_match(s, cur_match)
1273 deflate_state *s;
1274 IPos cur_match; /* current match */
1275{
1276 unsigned chain_length = s->max_chain_length;/* max hash chain length */
1277 register Bytef *scan = s->window + s->strstart; /* current string */
1278 register Bytef *match; /* matched string */
1279 register int len; /* length of current match */
1280 int best_len = s->prev_length; /* best match length so far */
1281 int nice_match = s->nice_match; /* stop if match long enough */
1282 IPos limit = s->strstart > (IPos)MAX_DIST(s) ?
1283 s->strstart - (IPos)MAX_DIST(s) : NIL;
1284 /* Stop when cur_match becomes <= limit. To simplify the code,
1285 * we prevent matches with the string of window index 0.
1286 */
1287 Posf *prev = s->prev;
1288 uInt wmask = s->w_mask;
1289
1290#ifdef UNALIGNED_OK
1291 /* Compare two bytes at a time. Note: this is not always beneficial.
1292 * Try with and without -DUNALIGNED_OK to check.
1293 */
1294 register Bytef *strend = s->window + s->strstart + MAX_MATCH - 1;
1295 register ush scan_start = *(ushf*)scan;
1296 register ush scan_end = *(ushf*)(scan+best_len-1);
1297#else
1298 register Bytef *strend = s->window + s->strstart + MAX_MATCH;
1299 register Byte scan_end1 = scan[best_len-1];
1300 register Byte scan_end = scan[best_len];
1301#endif
1302
1303 /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
1304 * It is easy to get rid of this optimization if necessary.
1305 */
1306 Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");
1307
1308 /* Do not waste too much time if we already have a good match: */
1309 if (s->prev_length >= s->good_match) {
1310 chain_length >>= 2;
1311 }
1312 /* Do not look for matches beyond the end of the input. This is necessary
1313 * to make deflate deterministic.
1314 */
1315 if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;
1316
1317 Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
1318
1319 do {
1320 Assert(cur_match < s->strstart, "no future");
1321 match = s->window + cur_match;
1322
1323 /* Skip to next match if the match length cannot increase
1324 * or if the match length is less than 2:
1325 */
1326#if (defined(UNALIGNED_OK) && MAX_MATCH == 258)
1327 /* This code assumes sizeof(unsigned short) == 2. Do not use
1328 * UNALIGNED_OK if your compiler uses a different size.
1329 */
1330 if (*(ushf*)(match+best_len-1) != scan_end ||
1331 *(ushf*)match != scan_start) continue;
1332
1333 /* It is not necessary to compare scan[2] and match[2] since they are
1334 * always equal when the other bytes match, given that the hash keys
1335 * are equal and that HASH_BITS >= 8. Compare 2 bytes at a time at
1336 * strstart+3, +5, ... up to strstart+257. We check for insufficient
1337 * lookahead only every 4th comparison; the 128th check will be made
1338 * at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is
1339 * necessary to put more guard bytes at the end of the window, or
1340 * to check more often for insufficient lookahead.
1341 */
1342 Assert(scan[2] == match[2], "scan[2]?");
1343 scan++, match++;
1344 do {
1345 } while (*(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1346 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1347 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1348 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1349 scan < strend);
1350 /* The funny "do {}" generates better code on most compilers */
1351
1352 /* Here, scan <= window+strstart+257 */
1353 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1354 if (*scan == *match) scan++;
1355
1356 len = (MAX_MATCH - 1) - (int)(strend-scan);
1357 scan = strend - (MAX_MATCH-1);
1358
1359#else /* UNALIGNED_OK */
1360
1361 if (match[best_len] != scan_end ||
1362 match[best_len-1] != scan_end1 ||
1363 *match != *scan ||
1364 *++match != scan[1]) continue;
1365
1366 /* The check at best_len-1 can be removed because it will be made
1367 * again later. (This heuristic is not always a win.)
1368 * It is not necessary to compare scan[2] and match[2] since they
1369 * are always equal when the other bytes match, given that
1370 * the hash keys are equal and that HASH_BITS >= 8.
1371 */
1372 scan += 2, match++;
1373 Assert(*scan == *match, "match[2]?");
1374
1375 /* We check for insufficient lookahead only every 8th comparison;
1376 * the 256th check will be made at strstart+258.
1377 */
1378 do {
1379 } while (*++scan == *++match && *++scan == *++match &&
1380 *++scan == *++match && *++scan == *++match &&
1381 *++scan == *++match && *++scan == *++match &&
1382 *++scan == *++match && *++scan == *++match &&
1383 scan < strend);
1384
1385 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1386
1387 len = MAX_MATCH - (int)(strend - scan);
1388 scan = strend - MAX_MATCH;
1389
1390#endif /* UNALIGNED_OK */
1391
1392 if (len > best_len) {
1393 s->match_start = cur_match;
1394 best_len = len;
1395 if (len >= nice_match) break;
1396#ifdef UNALIGNED_OK
1397 scan_end = *(ushf*)(scan+best_len-1);
1398#else
1399 scan_end1 = scan[best_len-1];
1400 scan_end = scan[best_len];
1401#endif
1402 }
1403 } while ((cur_match = prev[cur_match & wmask]) > limit
1404 && --chain_length != 0);
1405
1406 if ((uInt)best_len <= s->lookahead) return best_len;
1407 return s->lookahead;
1408}
1409#endif /* ASMV */
1410
1411#ifdef DEBUG_ZLIB
1412/* ===========================================================================
1413 * Check that the match at match_start is indeed a match.
1414 */
1415local void check_match(s, start, match, length)
1416 deflate_state *s;
1417 IPos start, match;
1418 int length;
1419{
1420 /* check that the match is indeed a match */
1421 if (zmemcmp((charf *)s->window + match,
1422 (charf *)s->window + start, length) != EQUAL) {
1423 fprintf(stderr, " start %u, match %u, length %d\n",
1424 start, match, length);
1425 do {
1426 fprintf(stderr, "%c%c", s->window[match++], s->window[start++]);
1427 } while (--length != 0);
1428 z_error("invalid match");
1429 }
1430 if (z_verbose > 1) {
1431 fprintf(stderr,"\\[%d,%d]", start-match, length);
1432 do { putc(s->window[start++], stderr); } while (--length != 0);
1433 }
1434}
1435#else
1436# define check_match(s, start, match, length)
1437#endif
1438
1439/* ===========================================================================
1440 * Fill the window when the lookahead becomes insufficient.
1441 * Updates strstart and lookahead.
1442 *
1443 * IN assertion: lookahead < MIN_LOOKAHEAD
1444 * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD
1445 * At least one byte has been read, or avail_in == 0; reads are
1446 * performed for at least two bytes (required for the zip translate_eol
1447 * option -- not supported here).
1448 */
1449local void fill_window(s)
1450 deflate_state *s;
1451{
1452 register unsigned n, m;
1453 register Posf *p;
1454 unsigned more; /* Amount of free space at the end of the window. */
1455 uInt wsize = s->w_size;
1456
1457 do {
1458 more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart);
1459
1460 /* Deal with !@#$% 64K limit: */
1461 if (more == 0 && s->strstart == 0 && s->lookahead == 0) {
1462 more = wsize;
1463
1464 } else if (more == (unsigned)(-1)) {
1465 /* Very unlikely, but possible on 16 bit machine if strstart == 0
1466 * and lookahead == 1 (input done one byte at time)
1467 */
1468 more--;
1469
1470 /* If the window is almost full and there is insufficient lookahead,
1471 * move the upper half to the lower one to make room in the upper half.
1472 */
1473 } else if (s->strstart >= wsize+MAX_DIST(s)) {
1474
1475 zmemcpy((charf *)s->window, (charf *)s->window+wsize,
1476 (unsigned)wsize);
1477 s->match_start -= wsize;
1478 s->strstart -= wsize; /* we now have strstart >= MAX_DIST */
1479 s->block_start -= (long) wsize;
1480
1481 /* Slide the hash table (could be avoided with 32 bit values
1482 at the expense of memory usage). We slide even when level == 0
1483 to keep the hash table consistent if we switch back to level > 0
1484 later. (Using level 0 permanently is not an optimal usage of
1485 zlib, so we don't care about this pathological case.)
1486 */
1487 n = s->hash_size;
1488 p = &s->head[n];
1489 do {
1490 m = *--p;
1491 *p = (Pos)(m >= wsize ? m-wsize : NIL);
1492 } while (--n);
1493
1494 n = wsize;
1495 p = &s->prev[n];
1496 do {
1497 m = *--p;
1498 *p = (Pos)(m >= wsize ? m-wsize : NIL);
1499 /* If n is not on any hash chain, prev[n] is garbage but
1500 * its value will never be used.
1501 */
1502 } while (--n);
1503 more += wsize;
1504 }
1505 if (s->strm->avail_in == 0) return;
1506
1507 /* If there was no sliding:
1508 * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 &&
1509 * more == window_size - lookahead - strstart
1510 * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1)
1511 * => more >= window_size - 2*WSIZE + 2
1512 * In the BIG_MEM or MMAP case (not yet supported),
1513 * window_size == input_size + MIN_LOOKAHEAD &&
1514 * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD.
1515 * Otherwise, window_size == 2*WSIZE so more >= 2.
1516 * If there was sliding, more >= WSIZE. So in all cases, more >= 2.
1517 */
1518 Assert(more >= 2, "more < 2");
1519
1520 n = read_buf(s->strm, (charf *)s->window + s->strstart + s->lookahead,
1521 more);
1522 s->lookahead += n;
1523
1524 /* Initialize the hash value now that we have some input: */
1525 if (s->lookahead >= MIN_MATCH) {
1526 s->ins_h = s->window[s->strstart];
1527 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
1528#if MIN_MATCH != 3
1529 Call UPDATE_HASH() MIN_MATCH-3 more times
1530#endif
1531 }
1532 /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage,
1533 * but this is not important since only literal bytes will be emitted.
1534 */
1535
1536 } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0);
1537}
1538
1539/* ===========================================================================
1540 * Flush the current block, with given end-of-file flag.
1541 * IN assertion: strstart is set to the end of the current match.
1542 */
1543#define FLUSH_BLOCK_ONLY(s, eof) { \
1544 _tr_flush_block(s, (s->block_start >= 0L ? \
1545 (charf *)&s->window[(unsigned)s->block_start] : \
1546 (charf *)Z_NULL), \
1547 (ulg)((long)s->strstart - s->block_start), \
1548 (eof)); \
1549 s->block_start = s->strstart; \
1550 flush_pending(s->strm); \
1551 Tracev((stderr,"[FLUSH]")); \
1552}
1553
1554/* Same but force premature exit if necessary. */
1555#define FLUSH_BLOCK(s, eof) { \
1556 FLUSH_BLOCK_ONLY(s, eof); \
1557 if (s->strm->avail_out == 0) return (eof) ? finish_started : need_more; \
1558}
1559
1560/* ===========================================================================
1561 * Copy without compression as much as possible from the input stream, return
1562 * the current block state.
1563 * This function does not insert new strings in the dictionary since
1564 * uncompressible data is probably not useful. This function is used
1565 * only for the level=0 compression option.
1566 * NOTE: this function should be optimized to avoid extra copying from
1567 * window to pending_buf.
1568 */
1569local block_state deflate_stored(s, flush)
1570 deflate_state *s;
1571 int flush;
1572{
1573 /* Stored blocks are limited to 0xffff bytes, pending_buf is limited
1574 * to pending_buf_size, and each stored block has a 5 byte header:
1575 */
1576 ulg max_block_size = 0xffff;
1577 ulg max_start;
1578
1579 if (max_block_size > s->pending_buf_size - 5) {
1580 max_block_size = s->pending_buf_size - 5;
1581 }
1582
1583 /* Copy as much as possible from input to output: */
1584 for (;;) {
1585 /* Fill the window as much as possible: */
1586 if (s->lookahead <= 1) {
1587
1588 Assert(s->strstart < s->w_size+MAX_DIST(s) ||
1589 s->block_start >= (long)s->w_size, "slide too late");
1590
1591 fill_window(s);
1592 if (s->lookahead == 0 && flush == Z_NO_FLUSH) return need_more;
1593
1594 if (s->lookahead == 0) break; /* flush the current block */
1595 }
1596 Assert(s->block_start >= 0L, "block gone");
1597
1598 s->strstart += s->lookahead;
1599 s->lookahead = 0;
1600
1601 /* Emit a stored block if pending_buf will be full: */
1602 max_start = s->block_start + max_block_size;
1603 if (s->strstart == 0 || (ulg)s->strstart >= max_start) {
1604 /* strstart == 0 is possible when wraparound on 16-bit machine */
1605 s->lookahead = (uInt)(s->strstart - max_start);
1606 s->strstart = (uInt)max_start;
1607 FLUSH_BLOCK(s, 0);
1608 }
1609 /* Flush if we may have to slide, otherwise block_start may become
1610 * negative and the data will be gone:
1611 */
1612 if (s->strstart - (uInt)s->block_start >= MAX_DIST(s)) {
1613 FLUSH_BLOCK(s, 0);
1614 }
1615 }
1616 FLUSH_BLOCK(s, flush == Z_FINISH);
1617 return flush == Z_FINISH ? finish_done : block_done;
1618}
1619
1620/* ===========================================================================
1621 * Compress as much as possible from the input stream, return the current
1622 * block state.
1623 * This function does not perform lazy evaluation of matches and inserts
1624 * new strings in the dictionary only for unmatched strings or for short
1625 * matches. It is used only for the fast compression options.
1626 */
1627local block_state deflate_fast(s, flush)
1628 deflate_state *s;
1629 int flush;
1630{
1631 IPos hash_head = NIL; /* head of the hash chain */
1632 int bflush; /* set if current block must be flushed */
1633
1634 for (;;) {
1635 /* Make sure that we always have enough lookahead, except
1636 * at the end of the input file. We need MAX_MATCH bytes
1637 * for the next match, plus MIN_MATCH bytes to insert the
1638 * string following the next match.
1639 */
1640 if (s->lookahead < MIN_LOOKAHEAD) {
1641 fill_window(s);
1642 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
1643 return need_more;
1644 }
1645 if (s->lookahead == 0) break; /* flush the current block */
1646 }
1647
1648 /* Insert the string window[strstart .. strstart+2] in the
1649 * dictionary, and set hash_head to the head of the hash chain:
1650 */
1651 if (s->lookahead >= MIN_MATCH) {
1652 INSERT_STRING(s, s->strstart, hash_head);
1653 }
1654
1655 /* Find the longest match, discarding those <= prev_length.
1656 * At this point we have always match_length < MIN_MATCH
1657 */
1658 if (hash_head != NIL && s->strstart - hash_head <= MAX_DIST(s)) {
1659 /* To simplify the code, we prevent matches with the string
1660 * of window index 0 (in particular we have to avoid a match
1661 * of the string with itself at the start of the input file).
1662 */
1663 if (s->strategy != Z_HUFFMAN_ONLY) {
1664 s->match_length = longest_match (s, hash_head);
1665 }
1666 /* longest_match() sets match_start */
1667 }
1668 if (s->match_length >= MIN_MATCH) {
1669 check_match(s, s->strstart, s->match_start, s->match_length);
1670
1671 bflush = _tr_tally(s, s->strstart - s->match_start,
1672 s->match_length - MIN_MATCH);
1673
1674 s->lookahead -= s->match_length;
1675
1676 /* Insert new strings in the hash table only if the match length
1677 * is not too large. This saves time but degrades compression.
1678 */
1679 if (s->match_length <= s->max_insert_length &&
1680 s->lookahead >= MIN_MATCH) {
1681 s->match_length--; /* string at strstart already in hash table */
1682 do {
1683 s->strstart++;
1684 INSERT_STRING(s, s->strstart, hash_head);
1685 /* strstart never exceeds WSIZE-MAX_MATCH, so there are
1686 * always MIN_MATCH bytes ahead.
1687 */
1688 } while (--s->match_length != 0);
1689 s->strstart++;
1690 } else {
1691 s->strstart += s->match_length;
1692 s->match_length = 0;
1693 s->ins_h = s->window[s->strstart];
1694 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
1695#if MIN_MATCH != 3
1696 Call UPDATE_HASH() MIN_MATCH-3 more times
1697#endif
1698 /* If lookahead < MIN_MATCH, ins_h is garbage, but it does not
1699 * matter since it will be recomputed at next deflate call.
1700 */
1701 }
1702 } else {
1703 /* No match, output a literal byte */
1704 Tracevv((stderr,"%c", s->window[s->strstart]));
1705 bflush = _tr_tally (s, 0, s->window[s->strstart]);
1706 s->lookahead--;
1707 s->strstart++;
1708 }
1709 if (bflush) FLUSH_BLOCK(s, 0);
1710 }
1711 FLUSH_BLOCK(s, flush == Z_FINISH);
1712 return flush == Z_FINISH ? finish_done : block_done;
1713}
1714
1715/* ===========================================================================
1716 * Same as above, but achieves better compression. We use a lazy
1717 * evaluation for matches: a match is finally adopted only if there is
1718 * no better match at the next window position.
1719 */
1720local block_state deflate_slow(s, flush)
1721 deflate_state *s;
1722 int flush;
1723{
1724 IPos hash_head = NIL; /* head of hash chain */
1725 int bflush; /* set if current block must be flushed */
1726
1727 /* Process the input block. */
1728 for (;;) {
1729 /* Make sure that we always have enough lookahead, except
1730 * at the end of the input file. We need MAX_MATCH bytes
1731 * for the next match, plus MIN_MATCH bytes to insert the
1732 * string following the next match.
1733 */
1734 if (s->lookahead < MIN_LOOKAHEAD) {
1735 fill_window(s);
1736 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
1737 return need_more;
1738 }
1739 if (s->lookahead == 0) break; /* flush the current block */
1740 }
1741
1742 /* Insert the string window[strstart .. strstart+2] in the
1743 * dictionary, and set hash_head to the head of the hash chain:
1744 */
1745 if (s->lookahead >= MIN_MATCH) {
1746 INSERT_STRING(s, s->strstart, hash_head);
1747 }
1748
1749 /* Find the longest match, discarding those <= prev_length.
1750 */
1751 s->prev_length = s->match_length, s->prev_match = s->match_start;
1752 s->match_length = MIN_MATCH-1;
1753
1754 if (hash_head != NIL && s->prev_length < s->max_lazy_match &&
1755 s->strstart - hash_head <= MAX_DIST(s)) {
1756 /* To simplify the code, we prevent matches with the string
1757 * of window index 0 (in particular we have to avoid a match
1758 * of the string with itself at the start of the input file).
1759 */
1760 if (s->strategy != Z_HUFFMAN_ONLY) {
1761 s->match_length = longest_match (s, hash_head);
1762 }
1763 /* longest_match() sets match_start */
1764
1765 if (s->match_length <= 5 && (s->strategy == Z_FILTERED ||
1766 (s->match_length == MIN_MATCH &&
1767 s->strstart - s->match_start > TOO_FAR))) {
1768
1769 /* If prev_match is also MIN_MATCH, match_start is garbage
1770 * but we will ignore the current match anyway.
1771 */
1772 s->match_length = MIN_MATCH-1;
1773 }
1774 }
1775 /* If there was a match at the previous step and the current
1776 * match is not better, output the previous match:
1777 */
1778 if (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) {
1779 uInt max_insert = s->strstart + s->lookahead - MIN_MATCH;
1780 /* Do not insert strings in hash table beyond this. */
1781
1782 check_match(s, s->strstart-1, s->prev_match, s->prev_length);
1783
1784 bflush = _tr_tally(s, s->strstart -1 - s->prev_match,
1785 s->prev_length - MIN_MATCH);
1786
1787 /* Insert in hash table all strings up to the end of the match.
1788 * strstart-1 and strstart are already inserted. If there is not
1789 * enough lookahead, the last two strings are not inserted in
1790 * the hash table.
1791 */
1792 s->lookahead -= s->prev_length-1;
1793 s->prev_length -= 2;
1794 do {
1795 if (++s->strstart <= max_insert) {
1796 INSERT_STRING(s, s->strstart, hash_head);
1797 }
1798 } while (--s->prev_length != 0);
1799 s->match_available = 0;
1800 s->match_length = MIN_MATCH-1;
1801 s->strstart++;
1802
1803 if (bflush) FLUSH_BLOCK(s, 0);
1804
1805 } else if (s->match_available) {
1806 /* If there was no match at the previous position, output a
1807 * single literal. If there was a match but the current match
1808 * is longer, truncate the previous match to a single literal.
1809 */
1810 Tracevv((stderr,"%c", s->window[s->strstart-1]));
1811 if (_tr_tally (s, 0, s->window[s->strstart-1])) {
1812 FLUSH_BLOCK_ONLY(s, 0);
1813 }
1814 s->strstart++;
1815 s->lookahead--;
1816 if (s->strm->avail_out == 0) return need_more;
1817 } else {
1818 /* There is no previous match to compare with, wait for
1819 * the next step to decide.
1820 */
1821 s->match_available = 1;
1822 s->strstart++;
1823 s->lookahead--;
1824 }
1825 }
1826 Assert (flush != Z_NO_FLUSH, "no flush?");
1827 if (s->match_available) {
1828 Tracevv((stderr,"%c", s->window[s->strstart-1]));
1829 _tr_tally (s, 0, s->window[s->strstart-1]);
1830 s->match_available = 0;
1831 }
1832 FLUSH_BLOCK(s, flush == Z_FINISH);
1833 return flush == Z_FINISH ? finish_done : block_done;
1834}
1835/* --- deflate.c */
1836
1837/* +++ trees.c */
1838/* trees.c -- output deflated data using Huffman coding
1839 * Copyright (C) 1995-1996 Jean-loup Gailly
1840 * For conditions of distribution and use, see copyright notice in zlib.h
1841 */
1842
1843/*
1844 * ALGORITHM
1845 *
1846 * The "deflation" process uses several Huffman trees. The more
1847 * common source values are represented by shorter bit sequences.
1848 *
1849 * Each code tree is stored in a compressed form which is itself
1850 * a Huffman encoding of the lengths of all the code strings (in
1851 * ascending order by source values). The actual code strings are
1852 * reconstructed from the lengths in the inflate process, as described
1853 * in the deflate specification.
1854 *
1855 * REFERENCES
1856 *
1857 * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification".
1858 * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc
1859 *
1860 * Storer, James A.
1861 * Data Compression: Methods and Theory, pp. 49-50.
1862 * Computer Science Press, 1988. ISBN 0-7167-8156-5.
1863 *
1864 * Sedgewick, R.
1865 * Algorithms, p290.
1866 * Addison-Wesley, 1983. ISBN 0-201-06672-6.
1867 */
1868
1869/* From: trees.c,v 1.11 1996/07/24 13:41:06 me Exp $ */
1870
1871/* #include "deflate.h" */
1872
1873#ifdef DEBUG_ZLIB
1874# include <ctype.h>
1875#endif
1876
1877/* ===========================================================================
1878 * Constants
1879 */
1880
1881#define MAX_BL_BITS 7
1882/* Bit length codes must not exceed MAX_BL_BITS bits */
1883
1884#define END_BLOCK 256
1885/* end of block literal code */
1886
1887#define REP_3_6 16
1888/* repeat previous bit length 3-6 times (2 bits of repeat count) */
1889
1890#define REPZ_3_10 17
1891/* repeat a zero length 3-10 times (3 bits of repeat count) */
1892
1893#define REPZ_11_138 18
1894/* repeat a zero length 11-138 times (7 bits of repeat count) */
1895
1896local int extra_lbits[LENGTH_CODES] /* extra bits for each length code */
1897 = {0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0};
1898
1899local int extra_dbits[D_CODES] /* extra bits for each distance code */
1900 = {0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13};
1901
1902local int extra_blbits[BL_CODES]/* extra bits for each bit length code */
1903 = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7};
1904
1905local uch bl_order[BL_CODES]
1906 = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15};
1907/* The lengths of the bit length codes are sent in order of decreasing
1908 * probability, to avoid transmitting the lengths for unused bit length codes.
1909 */
1910
1911#define Buf_size (8 * 2*sizeof(char))
1912/* Number of bits used within bi_buf. (bi_buf might be implemented on
1913 * more than 16 bits on some systems.)
1914 */
1915
1916/* ===========================================================================
1917 * Local data. These are initialized only once.
1918 */
1919
1920local ct_data static_ltree[L_CODES+2];
1921/* The static literal tree. Since the bit lengths are imposed, there is no
1922 * need for the L_CODES extra codes used during heap construction. However
1923 * The codes 286 and 287 are needed to build a canonical tree (see _tr_init
1924 * below).
1925 */
1926
1927local ct_data static_dtree[D_CODES];
1928/* The static distance tree. (Actually a trivial tree since all codes use
1929 * 5 bits.)
1930 */
1931
1932local uch dist_code[512];
1933/* distance codes. The first 256 values correspond to the distances
1934 * 3 .. 258, the last 256 values correspond to the top 8 bits of
1935 * the 15 bit distances.
1936 */
1937
1938local uch length_code[MAX_MATCH-MIN_MATCH+1];
1939/* length code for each normalized match length (0 == MIN_MATCH) */
1940
1941local int base_length[LENGTH_CODES];
1942/* First normalized length for each code (0 = MIN_MATCH) */
1943
1944local int base_dist[D_CODES];
1945/* First normalized distance for each code (0 = distance of 1) */
1946
1947struct static_tree_desc_s {
1948 ct_data *static_tree; /* static tree or NULL */
1949 intf *extra_bits; /* extra bits for each code or NULL */
1950 int extra_base; /* base index for extra_bits */
1951 int elems; /* max number of elements in the tree */
1952 int max_length; /* max bit length for the codes */
1953};
1954
1955local static_tree_desc static_l_desc =
1956{static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS};
1957
1958local static_tree_desc static_d_desc =
1959{static_dtree, extra_dbits, 0, D_CODES, MAX_BITS};
1960
1961local static_tree_desc static_bl_desc =
1962{(ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS};
1963
1964/* ===========================================================================
1965 * Local (static) routines in this file.
1966 */
1967
1968local void tr_static_init OF((void));
1969local void init_block OF((deflate_state *s));
1970local void pqdownheap OF((deflate_state *s, ct_data *tree, int k));
1971local void gen_bitlen OF((deflate_state *s, tree_desc *desc));
1972local void gen_codes OF((ct_data *tree, int max_code, ushf *bl_count));
1973local void build_tree OF((deflate_state *s, tree_desc *desc));
1974local void scan_tree OF((deflate_state *s, ct_data *tree, int max_code));
1975local void send_tree OF((deflate_state *s, ct_data *tree, int max_code));
1976local int build_bl_tree OF((deflate_state *s));
1977local void send_all_trees OF((deflate_state *s, int lcodes, int dcodes,
1978 int blcodes));
1979local void compress_block OF((deflate_state *s, ct_data *ltree,
1980 ct_data *dtree));
1981local void set_data_type OF((deflate_state *s));
1982local unsigned bi_reverse OF((unsigned value, int length));
1983local void bi_windup OF((deflate_state *s));
1984local void bi_flush OF((deflate_state *s));
1985local void copy_block OF((deflate_state *s, charf *buf, unsigned len,
1986 int header));
1987
1988#ifndef DEBUG_ZLIB
1989# define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len)
1990 /* Send a code of the given tree. c and tree must not have side effects */
1991
1992#else /* DEBUG_ZLIB */
1993# define send_code(s, c, tree) \
1994 { if (verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \
1995 send_bits(s, tree[c].Code, tree[c].Len); }
1996#endif
1997
1998#define d_code(dist) \
1999 ((dist) < 256 ? dist_code[dist] : dist_code[256+((dist)>>7)])
2000/* Mapping from a distance to a distance code. dist is the distance - 1 and
2001 * must not have side effects. dist_code[256] and dist_code[257] are never
2002 * used.
2003 */
2004
2005/* ===========================================================================
2006 * Output a short LSB first on the stream.
2007 * IN assertion: there is enough room in pendingBuf.
2008 */
2009#define put_short(s, w) { \
2010 put_byte(s, (uch)((w) & 0xff)); \
2011 put_byte(s, (uch)((ush)(w) >> 8)); \
2012}
2013
2014/* ===========================================================================
2015 * Send a value on a given number of bits.
2016 * IN assertion: length <= 16 and value fits in length bits.
2017 */
2018#ifdef DEBUG_ZLIB
2019local void send_bits OF((deflate_state *s, int value, int length));
2020
2021local void send_bits(s, value, length)
2022 deflate_state *s;
2023 int value; /* value to send */
2024 int length; /* number of bits */
2025{
2026 Tracevv((stderr," l %2d v %4x ", length, value));
2027 Assert(length > 0 && length <= 15, "invalid length");
2028 s->bits_sent += (ulg)length;
2029
2030 /* If not enough room in bi_buf, use (valid) bits from bi_buf and
2031 * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid))
2032 * unused bits in value.
2033 */
2034 if (s->bi_valid > (int)Buf_size - length) {
2035 s->bi_buf |= (value << s->bi_valid);
2036 put_short(s, s->bi_buf);
2037 s->bi_buf = (ush)value >> (Buf_size - s->bi_valid);
2038 s->bi_valid += length - Buf_size;
2039 } else {
2040 s->bi_buf |= value << s->bi_valid;
2041 s->bi_valid += length;
2042 }
2043}
2044#else /* !DEBUG_ZLIB */
2045
2046#define send_bits(s, value, length) \
2047{ int len = length;\
2048 if (s->bi_valid > (int)Buf_size - len) {\
2049 int val = value;\
2050 s->bi_buf |= (val << s->bi_valid);\
2051 put_short(s, s->bi_buf);\
2052 s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\
2053 s->bi_valid += len - Buf_size;\
2054 } else {\
2055 s->bi_buf |= (value) << s->bi_valid;\
2056 s->bi_valid += len;\
2057 }\
2058}
2059#endif /* DEBUG_ZLIB */
2060
2061
2062#define MAX(a,b) (a >= b ? a : b)
2063/* the arguments must not have side effects */
2064
2065/* ===========================================================================
2066 * Initialize the various 'constant' tables. In a multi-threaded environment,
2067 * this function may be called by two threads concurrently, but this is
2068 * harmless since both invocations do exactly the same thing.
2069 */
2070local void tr_static_init()
2071{
2072 static int static_init_done = 0;
2073 int n; /* iterates over tree elements */
2074 int bits; /* bit counter */
2075 int length; /* length value */
2076 int code; /* code value */
2077 int dist; /* distance index */
2078 ush bl_count[MAX_BITS+1];
2079 /* number of codes at each bit length for an optimal tree */
2080
2081 if (static_init_done) return;
2082
2083 /* Initialize the mapping length (0..255) -> length code (0..28) */
2084 length = 0;
2085 for (code = 0; code < LENGTH_CODES-1; code++) {
2086 base_length[code] = length;
2087 for (n = 0; n < (1<<extra_lbits[code]); n++) {
2088 length_code[length++] = (uch)code;
2089 }
2090 }
2091 Assert (length == 256, "tr_static_init: length != 256");
2092 /* Note that the length 255 (match length 258) can be represented
2093 * in two different ways: code 284 + 5 bits or code 285, so we
2094 * overwrite length_code[255] to use the best encoding:
2095 */
2096 length_code[length-1] = (uch)code;
2097
2098 /* Initialize the mapping dist (0..32K) -> dist code (0..29) */
2099 dist = 0;
2100 for (code = 0 ; code < 16; code++) {
2101 base_dist[code] = dist;
2102 for (n = 0; n < (1<<extra_dbits[code]); n++) {
2103 dist_code[dist++] = (uch)code;
2104 }
2105 }
2106 Assert (dist == 256, "tr_static_init: dist != 256");
2107 dist >>= 7; /* from now on, all distances are divided by 128 */
2108 for ( ; code < D_CODES; code++) {
2109 base_dist[code] = dist << 7;
2110 for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) {
2111 dist_code[256 + dist++] = (uch)code;
2112 }
2113 }
2114 Assert (dist == 256, "tr_static_init: 256+dist != 512");
2115
2116 /* Construct the codes of the static literal tree */
2117 for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
2118 n = 0;
2119 while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++;
2120 while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++;
2121 while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++;
2122 while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++;
2123 /* Codes 286 and 287 do not exist, but we must include them in the
2124 * tree construction to get a canonical Huffman tree (longest code
2125 * all ones)
2126 */
2127 gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count);
2128
2129 /* The static distance tree is trivial: */
2130 for (n = 0; n < D_CODES; n++) {
2131 static_dtree[n].Len = 5;
2132 static_dtree[n].Code = bi_reverse((unsigned)n, 5);
2133 }
2134 static_init_done = 1;
2135}
2136
2137/* ===========================================================================
2138 * Initialize the tree data structures for a new zlib stream.
2139 */
2140void _tr_init(s)
2141 deflate_state *s;
2142{
2143 tr_static_init();
2144
2145 s->compressed_len = 0L;
2146
2147 s->l_desc.dyn_tree = s->dyn_ltree;
2148 s->l_desc.stat_desc = &static_l_desc;
2149
2150 s->d_desc.dyn_tree = s->dyn_dtree;
2151 s->d_desc.stat_desc = &static_d_desc;
2152
2153 s->bl_desc.dyn_tree = s->bl_tree;
2154 s->bl_desc.stat_desc = &static_bl_desc;
2155
2156 s->bi_buf = 0;
2157 s->bi_valid = 0;
2158 s->last_eob_len = 8; /* enough lookahead for inflate */
2159#ifdef DEBUG_ZLIB
2160 s->bits_sent = 0L;
2161#endif
2162
2163 /* Initialize the first block of the first file: */
2164 init_block(s);
2165}
2166
2167/* ===========================================================================
2168 * Initialize a new block.
2169 */
2170local void init_block(s)
2171 deflate_state *s;
2172{
2173 int n; /* iterates over tree elements */
2174
2175 /* Initialize the trees. */
2176 for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0;
2177 for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0;
2178 for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0;
2179
2180 s->dyn_ltree[END_BLOCK].Freq = 1;
2181 s->opt_len = s->static_len = 0L;
2182 s->last_lit = s->matches = 0;
2183}
2184
2185#define SMALLEST 1
2186/* Index within the heap array of least frequent node in the Huffman tree */
2187
2188
2189/* ===========================================================================
2190 * Remove the smallest element from the heap and recreate the heap with
2191 * one less element. Updates heap and heap_len.
2192 */
2193#define pqremove(s, tree, top) \
2194{\
2195 top = s->heap[SMALLEST]; \
2196 s->heap[SMALLEST] = s->heap[s->heap_len--]; \
2197 pqdownheap(s, tree, SMALLEST); \
2198}
2199
2200/* ===========================================================================
2201 * Compares to subtrees, using the tree depth as tie breaker when
2202 * the subtrees have equal frequency. This minimizes the worst case length.
2203 */
2204#define smaller(tree, n, m, depth) \
2205 (tree[n].Freq < tree[m].Freq || \
2206 (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m]))
2207
2208/* ===========================================================================
2209 * Restore the heap property by moving down the tree starting at node k,
2210 * exchanging a node with the smallest of its two sons if necessary, stopping
2211 * when the heap property is re-established (each father smaller than its
2212 * two sons).
2213 */
2214local void pqdownheap(s, tree, k)
2215 deflate_state *s;
2216 ct_data *tree; /* the tree to restore */
2217 int k; /* node to move down */
2218{
2219 int v = s->heap[k];
2220 int j = k << 1; /* left son of k */
2221 while (j <= s->heap_len) {
2222 /* Set j to the smallest of the two sons: */
2223 if (j < s->heap_len &&
2224 smaller(tree, s->heap[j+1], s->heap[j], s->depth)) {
2225 j++;
2226 }
2227 /* Exit if v is smaller than both sons */
2228 if (smaller(tree, v, s->heap[j], s->depth)) break;
2229
2230 /* Exchange v with the smallest son */
2231 s->heap[k] = s->heap[j]; k = j;
2232
2233 /* And continue down the tree, setting j to the left son of k */
2234 j <<= 1;
2235 }
2236 s->heap[k] = v;
2237}
2238
2239/* ===========================================================================
2240 * Compute the optimal bit lengths for a tree and update the total bit length
2241 * for the current block.
2242 * IN assertion: the fields freq and dad are set, heap[heap_max] and
2243 * above are the tree nodes sorted by increasing frequency.
2244 * OUT assertions: the field len is set to the optimal bit length, the
2245 * array bl_count contains the frequencies for each bit length.
2246 * The length opt_len is updated; static_len is also updated if stree is
2247 * not null.
2248 */
2249local void gen_bitlen(s, desc)
2250 deflate_state *s;
2251 tree_desc *desc; /* the tree descriptor */
2252{
2253 ct_data *tree = desc->dyn_tree;
2254 int max_code = desc->max_code;
2255 ct_data *stree = desc->stat_desc->static_tree;
2256 intf *extra = desc->stat_desc->extra_bits;
2257 int base = desc->stat_desc->extra_base;
2258 int max_length = desc->stat_desc->max_length;
2259 int h; /* heap index */
2260 int n, m; /* iterate over the tree elements */
2261 int bits; /* bit length */
2262 int xbits; /* extra bits */
2263 ush f; /* frequency */
2264 int overflow = 0; /* number of elements with bit length too large */
2265
2266 for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0;
2267
2268 /* In a first pass, compute the optimal bit lengths (which may
2269 * overflow in the case of the bit length tree).
2270 */
2271 tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */
2272
2273 for (h = s->heap_max+1; h < HEAP_SIZE; h++) {
2274 n = s->heap[h];
2275 bits = tree[tree[n].Dad].Len + 1;
2276 if (bits > max_length) bits = max_length, overflow++;
2277 tree[n].Len = (ush)bits;
2278 /* We overwrite tree[n].Dad which is no longer needed */
2279
2280 if (n > max_code) continue; /* not a leaf node */
2281
2282 s->bl_count[bits]++;
2283 xbits = 0;
2284 if (n >= base) xbits = extra[n-base];
2285 f = tree[n].Freq;
2286 s->opt_len += (ulg)f * (bits + xbits);
2287 if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits);
2288 }
2289 if (overflow == 0) return;
2290
2291 Trace((stderr,"\nbit length overflow\n"));
2292 /* This happens for example on obj2 and pic of the Calgary corpus */
2293
2294 /* Find the first bit length which could increase: */
2295 do {
2296 bits = max_length-1;
2297 while (s->bl_count[bits] == 0) bits--;
2298 s->bl_count[bits]--; /* move one leaf down the tree */
2299 s->bl_count[bits+1] += 2; /* move one overflow item as its brother */
2300 s->bl_count[max_length]--;
2301 /* The brother of the overflow item also moves one step up,
2302 * but this does not affect bl_count[max_length]
2303 */
2304 overflow -= 2;
2305 } while (overflow > 0);
2306
2307 /* Now recompute all bit lengths, scanning in increasing frequency.
2308 * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
2309 * lengths instead of fixing only the wrong ones. This idea is taken
2310 * from 'ar' written by Haruhiko Okumura.)
2311 */
2312 for (bits = max_length; bits != 0; bits--) {
2313 n = s->bl_count[bits];
2314 while (n != 0) {
2315 m = s->heap[--h];
2316 if (m > max_code) continue;
2317 if (tree[m].Len != (unsigned) bits) {
2318 Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits));
2319 s->opt_len += ((long)bits - (long)tree[m].Len)
2320 *(long)tree[m].Freq;
2321 tree[m].Len = (ush)bits;
2322 }
2323 n--;
2324 }
2325 }
2326}
2327
2328/* ===========================================================================
2329 * Generate the codes for a given tree and bit counts (which need not be
2330 * optimal).
2331 * IN assertion: the array bl_count contains the bit length statistics for
2332 * the given tree and the field len is set for all tree elements.
2333 * OUT assertion: the field code is set for all tree elements of non
2334 * zero code length.
2335 */
2336local void gen_codes (tree, max_code, bl_count)
2337 ct_data *tree; /* the tree to decorate */
2338 int max_code; /* largest code with non zero frequency */
2339 ushf *bl_count; /* number of codes at each bit length */
2340{
2341 ush next_code[MAX_BITS+1]; /* next code value for each bit length */
2342 ush code = 0; /* running code value */
2343 int bits; /* bit index */
2344 int n; /* code index */
2345
2346 /* The distribution counts are first used to generate the code values
2347 * without bit reversal.
2348 */
2349 for (bits = 1; bits <= MAX_BITS; bits++) {
2350 next_code[bits] = code = (code + bl_count[bits-1]) << 1;
2351 }
2352 /* Check that the bit counts in bl_count are consistent. The last code
2353 * must be all ones.
2354 */
2355 Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1,
2356 "inconsistent bit counts");
2357 Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
2358
2359 for (n = 0; n <= max_code; n++) {
2360 int len = tree[n].Len;
2361 if (len == 0) continue;
2362 /* Now reverse the bits */
2363 tree[n].Code = bi_reverse(next_code[len]++, len);
2364
2365 Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
2366 n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1));
2367 }
2368}
2369
2370/* ===========================================================================
2371 * Construct one Huffman tree and assigns the code bit strings and lengths.
2372 * Update the total bit length for the current block.
2373 * IN assertion: the field freq is set for all tree elements.
2374 * OUT assertions: the fields len and code are set to the optimal bit length
2375 * and corresponding code. The length opt_len is updated; static_len is
2376 * also updated if stree is not null. The field max_code is set.
2377 */
2378local void build_tree(s, desc)
2379 deflate_state *s;
2380 tree_desc *desc; /* the tree descriptor */
2381{
2382 ct_data *tree = desc->dyn_tree;
2383 ct_data *stree = desc->stat_desc->static_tree;
2384 int elems = desc->stat_desc->elems;
2385 int n, m; /* iterate over heap elements */
2386 int max_code = -1; /* largest code with non zero frequency */
2387 int node; /* new node being created */
2388
2389 /* Construct the initial heap, with least frequent element in
2390 * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
2391 * heap[0] is not used.
2392 */
2393 s->heap_len = 0, s->heap_max = HEAP_SIZE;
2394
2395 for (n = 0; n < elems; n++) {
2396 if (tree[n].Freq != 0) {
2397 s->heap[++(s->heap_len)] = max_code = n;
2398 s->depth[n] = 0;
2399 } else {
2400 tree[n].Len = 0;
2401 }
2402 }
2403
2404 /* The pkzip format requires that at least one distance code exists,
2405 * and that at least one bit should be sent even if there is only one
2406 * possible code. So to avoid special checks later on we force at least
2407 * two codes of non zero frequency.
2408 */
2409 while (s->heap_len < 2) {
2410 node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0);
2411 tree[node].Freq = 1;
2412 s->depth[node] = 0;
2413 s->opt_len--; if (stree) s->static_len -= stree[node].Len;
2414 /* node is 0 or 1 so it does not have extra bits */
2415 }
2416 desc->max_code = max_code;
2417
2418 /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
2419 * establish sub-heaps of increasing lengths:
2420 */
2421 for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n);
2422
2423 /* Construct the Huffman tree by repeatedly combining the least two
2424 * frequent nodes.
2425 */
2426 node = elems; /* next internal node of the tree */
2427 do {
2428 pqremove(s, tree, n); /* n = node of least frequency */
2429 m = s->heap[SMALLEST]; /* m = node of next least frequency */
2430
2431 s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */
2432 s->heap[--(s->heap_max)] = m;
2433
2434 /* Create a new node father of n and m */
2435 tree[node].Freq = tree[n].Freq + tree[m].Freq;
2436 s->depth[node] = (uch) (MAX(s->depth[n], s->depth[m]) + 1);
2437 tree[n].Dad = tree[m].Dad = (ush)node;
2438#ifdef DUMP_BL_TREE
2439 if (tree == s->bl_tree) {
2440 fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)",
2441 node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq);
2442 }
2443#endif
2444 /* and insert the new node in the heap */
2445 s->heap[SMALLEST] = node++;
2446 pqdownheap(s, tree, SMALLEST);
2447
2448 } while (s->heap_len >= 2);
2449
2450 s->heap[--(s->heap_max)] = s->heap[SMALLEST];
2451
2452 /* At this point, the fields freq and dad are set. We can now
2453 * generate the bit lengths.
2454 */
2455 gen_bitlen(s, (tree_desc *)desc);
2456
2457 /* The field len is now set, we can generate the bit codes */
2458 gen_codes ((ct_data *)tree, max_code, s->bl_count);
2459}
2460
2461/* ===========================================================================
2462 * Scan a literal or distance tree to determine the frequencies of the codes
2463 * in the bit length tree.
2464 */
2465local void scan_tree (s, tree, max_code)
2466 deflate_state *s;
2467 ct_data *tree; /* the tree to be scanned */
2468 int max_code; /* and its largest code of non zero frequency */
2469{
2470 int n; /* iterates over all tree elements */
2471 int prevlen = -1; /* last emitted length */
2472 int curlen; /* length of current code */
2473 int nextlen = tree[0].Len; /* length of next code */
2474 int count = 0; /* repeat count of the current code */
2475 int max_count = 7; /* max repeat count */
2476 int min_count = 4; /* min repeat count */
2477
2478 if (nextlen == 0) max_count = 138, min_count = 3;
2479 tree[max_code+1].Len = (ush)0xffff; /* guard */
2480
2481 for (n = 0; n <= max_code; n++) {
2482 curlen = nextlen; nextlen = tree[n+1].Len;
2483 if (++count < max_count && curlen == nextlen) {
2484 continue;
2485 } else if (count < min_count) {
2486 s->bl_tree[curlen].Freq += count;
2487 } else if (curlen != 0) {
2488 if (curlen != prevlen) s->bl_tree[curlen].Freq++;
2489 s->bl_tree[REP_3_6].Freq++;
2490 } else if (count <= 10) {
2491 s->bl_tree[REPZ_3_10].Freq++;
2492 } else {
2493 s->bl_tree[REPZ_11_138].Freq++;
2494 }
2495 count = 0; prevlen = curlen;
2496 if (nextlen == 0) {
2497 max_count = 138, min_count = 3;
2498 } else if (curlen == nextlen) {
2499 max_count = 6, min_count = 3;
2500 } else {
2501 max_count = 7, min_count = 4;
2502 }
2503 }
2504}
2505
2506/* ===========================================================================
2507 * Send a literal or distance tree in compressed form, using the codes in
2508 * bl_tree.
2509 */
2510local void send_tree (s, tree, max_code)
2511 deflate_state *s;
2512 ct_data *tree; /* the tree to be scanned */
2513 int max_code; /* and its largest code of non zero frequency */
2514{
2515 int n; /* iterates over all tree elements */
2516 int prevlen = -1; /* last emitted length */
2517 int curlen; /* length of current code */
2518 int nextlen = tree[0].Len; /* length of next code */
2519 int count = 0; /* repeat count of the current code */
2520 int max_count = 7; /* max repeat count */
2521 int min_count = 4; /* min repeat count */
2522
2523 /* tree[max_code+1].Len = -1; */ /* guard already set */
2524 if (nextlen == 0) max_count = 138, min_count = 3;
2525
2526 for (n = 0; n <= max_code; n++) {
2527 curlen = nextlen; nextlen = tree[n+1].Len;
2528 if (++count < max_count && curlen == nextlen) {
2529 continue;
2530 } else if (count < min_count) {
2531 do { send_code(s, curlen, s->bl_tree); } while (--count != 0);
2532
2533 } else if (curlen != 0) {
2534 if (curlen != prevlen) {
2535 send_code(s, curlen, s->bl_tree); count--;
2536 }
2537 Assert(count >= 3 && count <= 6, " 3_6?");
2538 send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2);
2539
2540 } else if (count <= 10) {
2541 send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3);
2542
2543 } else {
2544 send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7);
2545 }
2546 count = 0; prevlen = curlen;
2547 if (nextlen == 0) {
2548 max_count = 138, min_count = 3;
2549 } else if (curlen == nextlen) {
2550 max_count = 6, min_count = 3;
2551 } else {
2552 max_count = 7, min_count = 4;
2553 }
2554 }
2555}
2556
2557/* ===========================================================================
2558 * Construct the Huffman tree for the bit lengths and return the index in
2559 * bl_order of the last bit length code to send.
2560 */
2561local int build_bl_tree(s)
2562 deflate_state *s;
2563{
2564 int max_blindex; /* index of last bit length code of non zero freq */
2565
2566 /* Determine the bit length frequencies for literal and distance trees */
2567 scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code);
2568 scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code);
2569
2570 /* Build the bit length tree: */
2571 build_tree(s, (tree_desc *)(&(s->bl_desc)));
2572 /* opt_len now includes the length of the tree representations, except
2573 * the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
2574 */
2575
2576 /* Determine the number of bit length codes to send. The pkzip format
2577 * requires that at least 4 bit length codes be sent. (appnote.txt says
2578 * 3 but the actual value used is 4.)
2579 */
2580 for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) {
2581 if (s->bl_tree[bl_order[max_blindex]].Len != 0) break;
2582 }
2583 /* Update opt_len to include the bit length tree and counts */
2584 s->opt_len += 3*(max_blindex+1) + 5+5+4;
2585 Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld",
2586 s->opt_len, s->static_len));
2587
2588 return max_blindex;
2589}
2590
2591/* ===========================================================================
2592 * Send the header for a block using dynamic Huffman trees: the counts, the
2593 * lengths of the bit length codes, the literal tree and the distance tree.
2594 * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
2595 */
2596local void send_all_trees(s, lcodes, dcodes, blcodes)
2597 deflate_state *s;
2598 int lcodes, dcodes, blcodes; /* number of codes for each tree */
2599{
2600 int rank; /* index in bl_order */
2601
2602 Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
2603 Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
2604 "too many codes");
2605 Tracev((stderr, "\nbl counts: "));
2606 send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */
2607 send_bits(s, dcodes-1, 5);
2608 send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */
2609 for (rank = 0; rank < blcodes; rank++) {
2610 Tracev((stderr, "\nbl code %2d ", bl_order[rank]));
2611 send_bits(s, s->bl_tree[bl_order[rank]].Len, 3);
2612 }
2613 Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent));
2614
2615 send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */
2616 Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent));
2617
2618 send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */
2619 Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent));
2620}
2621
2622/* ===========================================================================
2623 * Send a stored block
2624 */
2625void _tr_stored_block(s, buf, stored_len, eof)
2626 deflate_state *s;
2627 charf *buf; /* input block */
2628 ulg stored_len; /* length of input block */
2629 int eof; /* true if this is the last block for a file */
2630{
2631 send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */
2632 s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L;
2633 s->compressed_len += (stored_len + 4) << 3;
2634
2635 copy_block(s, buf, (unsigned)stored_len, 1); /* with header */
2636}
2637
2638/* Send just the `stored block' type code without any length bytes or data.
2639 */
2640void _tr_stored_type_only(s)
2641 deflate_state *s;
2642{
2643 send_bits(s, (STORED_BLOCK << 1), 3);
2644 bi_windup(s);
2645 s->compressed_len = (s->compressed_len + 3) & ~7L;
2646}
2647
2648
2649/* ===========================================================================
2650 * Send one empty static block to give enough lookahead for inflate.
2651 * This takes 10 bits, of which 7 may remain in the bit buffer.
2652 * The current inflate code requires 9 bits of lookahead. If the
2653 * last two codes for the previous block (real code plus EOB) were coded
2654 * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode
2655 * the last real code. In this case we send two empty static blocks instead
2656 * of one. (There are no problems if the previous block is stored or fixed.)
2657 * To simplify the code, we assume the worst case of last real code encoded
2658 * on one bit only.
2659 */
2660void _tr_align(s)
2661 deflate_state *s;
2662{
2663 send_bits(s, STATIC_TREES<<1, 3);
2664 send_code(s, END_BLOCK, static_ltree);
2665 s->compressed_len += 10L; /* 3 for block type, 7 for EOB */
2666 bi_flush(s);
2667 /* Of the 10 bits for the empty block, we have already sent
2668 * (10 - bi_valid) bits. The lookahead for the last real code (before
2669 * the EOB of the previous block) was thus at least one plus the length
2670 * of the EOB plus what we have just sent of the empty static block.
2671 */
2672 if (1 + s->last_eob_len + 10 - s->bi_valid < 9) {
2673 send_bits(s, STATIC_TREES<<1, 3);
2674 send_code(s, END_BLOCK, static_ltree);
2675 s->compressed_len += 10L;
2676 bi_flush(s);
2677 }
2678 s->last_eob_len = 7;
2679}
2680
2681/* ===========================================================================
2682 * Determine the best encoding for the current block: dynamic trees, static
2683 * trees or store, and output the encoded block to the zip file. This function
2684 * returns the total compressed length for the file so far.
2685 */
2686ulg _tr_flush_block(s, buf, stored_len, eof)
2687 deflate_state *s;
2688 charf *buf; /* input block, or NULL if too old */
2689 ulg stored_len; /* length of input block */
2690 int eof; /* true if this is the last block for a file */
2691{
2692 ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
2693 int max_blindex = 0; /* index of last bit length code of non zero freq */
2694
2695 /* Build the Huffman trees unless a stored block is forced */
2696 if (s->level > 0) {
2697
2698 /* Check if the file is ascii or binary */
2699 if (s->data_type == Z_UNKNOWN) set_data_type(s);
2700
2701 /* Construct the literal and distance trees */
2702 build_tree(s, (tree_desc *)(&(s->l_desc)));
2703 Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len,
2704 s->static_len));
2705
2706 build_tree(s, (tree_desc *)(&(s->d_desc)));
2707 Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len,
2708 s->static_len));
2709 /* At this point, opt_len and static_len are the total bit lengths of
2710 * the compressed block data, excluding the tree representations.
2711 */
2712
2713 /* Build the bit length tree for the above two trees, and get the index
2714 * in bl_order of the last bit length code to send.
2715 */
2716 max_blindex = build_bl_tree(s);
2717
2718 /* Determine the best encoding. Compute first the block length in bytes*/
2719 opt_lenb = (s->opt_len+3+7)>>3;
2720 static_lenb = (s->static_len+3+7)>>3;
2721
2722 Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
2723 opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
2724 s->last_lit));
2725
2726 if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
2727
2728 } else {
2729 Assert(buf != (char*)0, "lost buf");
2730 opt_lenb = static_lenb = stored_len + 5; /* force a stored block */
2731 }
2732
2733 /* If compression failed and this is the first and last block,
2734 * and if the .zip file can be seeked (to rewrite the local header),
2735 * the whole file is transformed into a stored file:
2736 */
2737#ifdef STORED_FILE_OK
2738# ifdef FORCE_STORED_FILE
2739 if (eof && s->compressed_len == 0L) { /* force stored file */
2740# else
2741 if (stored_len <= opt_lenb && eof && s->compressed_len==0L && seekable()) {
2742# endif
2743 /* Since LIT_BUFSIZE <= 2*WSIZE, the input data must be there: */
2744 if (buf == (charf*)0) error ("block vanished");
2745
2746 copy_block(s, buf, (unsigned)stored_len, 0); /* without header */
2747 s->compressed_len = stored_len << 3;
2748 s->method = STORED;
2749 } else
2750#endif /* STORED_FILE_OK */
2751
2752#ifdef FORCE_STORED
2753 if (buf != (char*)0) { /* force stored block */
2754#else
2755 if (stored_len+4 <= opt_lenb && buf != (char*)0) {
2756 /* 4: two words for the lengths */
2757#endif
2758 /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
2759 * Otherwise we can't have processed more than WSIZE input bytes since
2760 * the last block flush, because compression would have been
2761 * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
2762 * transform a block into a stored block.
2763 */
2764 _tr_stored_block(s, buf, stored_len, eof);
2765
2766#ifdef FORCE_STATIC
2767 } else if (static_lenb >= 0) { /* force static trees */
2768#else
2769 } else if (static_lenb == opt_lenb) {
2770#endif
2771 send_bits(s, (STATIC_TREES<<1)+eof, 3);
2772 compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree);
2773 s->compressed_len += 3 + s->static_len;
2774 } else {
2775 send_bits(s, (DYN_TREES<<1)+eof, 3);
2776 send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1,
2777 max_blindex+1);
2778 compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree);
2779 s->compressed_len += 3 + s->opt_len;
2780 }
2781 Assert (s->compressed_len == s->bits_sent, "bad compressed size");
2782 init_block(s);
2783
2784 if (eof) {
2785 bi_windup(s);
2786 s->compressed_len += 7; /* align on byte boundary */
2787 }
2788 Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3,
2789 s->compressed_len-7*eof));
2790
2791 return s->compressed_len >> 3;
2792}
2793
2794/* ===========================================================================
2795 * Save the match info and tally the frequency counts. Return true if
2796 * the current block must be flushed.
2797 */
2798int _tr_tally (s, dist, lc)
2799 deflate_state *s;
2800 unsigned dist; /* distance of matched string */
2801 unsigned lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */
2802{
2803 s->d_buf[s->last_lit] = (ush)dist;
2804 s->l_buf[s->last_lit++] = (uch)lc;
2805 if (dist == 0) {
2806 /* lc is the unmatched char */
2807 s->dyn_ltree[lc].Freq++;
2808 } else {
2809 s->matches++;
2810 /* Here, lc is the match length - MIN_MATCH */
2811 dist--; /* dist = match distance - 1 */
2812 Assert((ush)dist < (ush)MAX_DIST(s) &&
2813 (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
2814 (ush)d_code(dist) < (ush)D_CODES, "_tr_tally: bad match");
2815
2816 s->dyn_ltree[length_code[lc]+LITERALS+1].Freq++;
2817 s->dyn_dtree[d_code(dist)].Freq++;
2818 }
2819
2820 /* Try to guess if it is profitable to stop the current block here */
2821 if (s->level > 2 && (s->last_lit & 0xfff) == 0) {
2822 /* Compute an upper bound for the compressed length */
2823 ulg out_length = (ulg)s->last_lit*8L;
2824 ulg in_length = (ulg)((long)s->strstart - s->block_start);
2825 int dcode;
2826 for (dcode = 0; dcode < D_CODES; dcode++) {
2827 out_length += (ulg)s->dyn_dtree[dcode].Freq *
2828 (5L+extra_dbits[dcode]);
2829 }
2830 out_length >>= 3;
2831 Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ",
2832 s->last_lit, in_length, out_length,
2833 100L - out_length*100L/in_length));
2834 if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1;
2835 }
2836 return (s->last_lit == s->lit_bufsize-1);
2837 /* We avoid equality with lit_bufsize because of wraparound at 64K
2838 * on 16 bit machines and because stored blocks are restricted to
2839 * 64K-1 bytes.
2840 */
2841}
2842
2843/* ===========================================================================
2844 * Send the block data compressed using the given Huffman trees
2845 */
2846local void compress_block(s, ltree, dtree)
2847 deflate_state *s;
2848 ct_data *ltree; /* literal tree */
2849 ct_data *dtree; /* distance tree */
2850{
2851 unsigned dist; /* distance of matched string */
2852 int lc; /* match length or unmatched char (if dist == 0) */
2853 unsigned lx = 0; /* running index in l_buf */
2854 unsigned code; /* the code to send */
2855 int extra; /* number of extra bits to send */
2856
2857 if (s->last_lit != 0) do {
2858 dist = s->d_buf[lx];
2859 lc = s->l_buf[lx++];
2860 if (dist == 0) {
2861 send_code(s, lc, ltree); /* send a literal byte */
2862 Tracecv(isgraph(lc), (stderr," '%c' ", lc));
2863 } else {
2864 /* Here, lc is the match length - MIN_MATCH */
2865 code = length_code[lc];
2866 send_code(s, code+LITERALS+1, ltree); /* send the length code */
2867 extra = extra_lbits[code];
2868 if (extra != 0) {
2869 lc -= base_length[code];
2870 send_bits(s, lc, extra); /* send the extra length bits */
2871 }
2872 dist--; /* dist is now the match distance - 1 */
2873 code = d_code(dist);
2874 Assert (code < D_CODES, "bad d_code");
2875
2876 send_code(s, code, dtree); /* send the distance code */
2877 extra = extra_dbits[code];
2878 if (extra != 0) {
2879 dist -= base_dist[code];
2880 send_bits(s, dist, extra); /* send the extra distance bits */
2881 }
2882 } /* literal or match pair ? */
2883
2884 /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */
2885 Assert(s->pending < s->lit_bufsize + 2*lx, "pendingBuf overflow");
2886
2887 } while (lx < s->last_lit);
2888
2889 send_code(s, END_BLOCK, ltree);
2890 s->last_eob_len = ltree[END_BLOCK].Len;
2891}
2892
2893/* ===========================================================================
2894 * Set the data type to ASCII or BINARY, using a crude approximation:
2895 * binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise.
2896 * IN assertion: the fields freq of dyn_ltree are set and the total of all
2897 * frequencies does not exceed 64K (to fit in an int on 16 bit machines).
2898 */
2899local void set_data_type(s)
2900 deflate_state *s;
2901{
2902 int n = 0;
2903 unsigned ascii_freq = 0;
2904 unsigned bin_freq = 0;
2905 while (n < 7) bin_freq += s->dyn_ltree[n++].Freq;
2906 while (n < 128) ascii_freq += s->dyn_ltree[n++].Freq;
2907 while (n < LITERALS) bin_freq += s->dyn_ltree[n++].Freq;
2908 s->data_type = (Byte)(bin_freq > (ascii_freq >> 2) ? Z_BINARY : Z_ASCII);
2909}
2910
2911/* ===========================================================================
2912 * Reverse the first len bits of a code, using straightforward code (a faster
2913 * method would use a table)
2914 * IN assertion: 1 <= len <= 15
2915 */
2916local unsigned bi_reverse(code, len)
2917 unsigned code; /* the value to invert */
2918 int len; /* its bit length */
2919{
2920 register unsigned res = 0;
2921 do {
2922 res |= code & 1;
2923 code >>= 1, res <<= 1;
2924 } while (--len > 0);
2925 return res >> 1;
2926}
2927
2928/* ===========================================================================
2929 * Flush the bit buffer, keeping at most 7 bits in it.
2930 */
2931local void bi_flush(s)
2932 deflate_state *s;
2933{
2934 if (s->bi_valid == 16) {
2935 put_short(s, s->bi_buf);
2936 s->bi_buf = 0;
2937 s->bi_valid = 0;
2938 } else if (s->bi_valid >= 8) {
2939 put_byte(s, (Byte)s->bi_buf);
2940 s->bi_buf >>= 8;
2941 s->bi_valid -= 8;
2942 }
2943}
2944
2945/* ===========================================================================
2946 * Flush the bit buffer and align the output on a byte boundary
2947 */
2948local void bi_windup(s)
2949 deflate_state *s;
2950{
2951 if (s->bi_valid > 8) {
2952 put_short(s, s->bi_buf);
2953 } else if (s->bi_valid > 0) {
2954 put_byte(s, (Byte)s->bi_buf);
2955 }
2956 s->bi_buf = 0;
2957 s->bi_valid = 0;
2958#ifdef DEBUG_ZLIB
2959 s->bits_sent = (s->bits_sent+7) & ~7;
2960#endif
2961}
2962
2963/* ===========================================================================
2964 * Copy a stored block, storing first the length and its
2965 * one's complement if requested.
2966 */
2967local void copy_block(s, buf, len, header)
2968 deflate_state *s;
2969 charf *buf; /* the input data */
2970 unsigned len; /* its length */
2971 int header; /* true if block header must be written */
2972{
2973 bi_windup(s); /* align on byte boundary */
2974 s->last_eob_len = 8; /* enough lookahead for inflate */
2975
2976 if (header) {
2977 put_short(s, (ush)len);
2978 put_short(s, (ush)~len);
2979#ifdef DEBUG_ZLIB
2980 s->bits_sent += 2*16;
2981#endif
2982 }
2983#ifdef DEBUG_ZLIB
2984 s->bits_sent += (ulg)len<<3;
2985#endif
2986 /* bundle up the put_byte(s, *buf++) calls */
2987 zmemcpy(&s->pending_buf[s->pending], buf, len);
2988 s->pending += len;
2989}
2990/* --- trees.c */
2991
2992/* +++ inflate.c */
2993/* inflate.c -- zlib interface to inflate modules
2994 * Copyright (C) 1995-1996 Mark Adler
2995 * For conditions of distribution and use, see copyright notice in zlib.h
2996 */
2997
2998/* #include "zutil.h" */
2999
3000/* +++ infblock.h */
3001/* infblock.h -- header to use infblock.c
3002 * Copyright (C) 1995-1996 Mark Adler
3003 * For conditions of distribution and use, see copyright notice in zlib.h
3004 */
3005
3006/* WARNING: this file should *not* be used by applications. It is
3007 part of the implementation of the compression library and is
3008 subject to change. Applications should only use zlib.h.
3009 */
3010
3011struct inflate_blocks_state;
3012typedef struct inflate_blocks_state FAR inflate_blocks_statef;
3013
3014extern inflate_blocks_statef * inflate_blocks_new OF((
3015 z_streamp z,
3016 check_func c, /* check function */
3017 uInt w)); /* window size */
3018
3019extern int inflate_blocks OF((
3020 inflate_blocks_statef *,
3021 z_streamp ,
3022 int)); /* initial return code */
3023
3024extern void inflate_blocks_reset OF((
3025 inflate_blocks_statef *,
3026 z_streamp ,
3027 uLongf *)); /* check value on output */
3028
3029extern int inflate_blocks_free OF((
3030 inflate_blocks_statef *,
3031 z_streamp ,
3032 uLongf *)); /* check value on output */
3033
3034extern void inflate_set_dictionary OF((
3035 inflate_blocks_statef *s,
3036 const Bytef *d, /* dictionary */
3037 uInt n)); /* dictionary length */
3038
3039extern int inflate_addhistory OF((
3040 inflate_blocks_statef *,
3041 z_streamp));
3042
3043extern int inflate_packet_flush OF((
3044 inflate_blocks_statef *));
3045/* --- infblock.h */
3046
3047#ifndef NO_DUMMY_DECL
3048struct inflate_blocks_state {int dummy;}; /* for buggy compilers */
3049#endif
3050
3051/* inflate private state */
3052struct internal_state {
3053
3054 /* mode */
3055 enum {
3056 METHOD, /* waiting for method byte */
3057 FLAG, /* waiting for flag byte */
3058 DICT4, /* four dictionary check bytes to go */
3059 DICT3, /* three dictionary check bytes to go */
3060 DICT2, /* two dictionary check bytes to go */
3061 DICT1, /* one dictionary check byte to go */
3062 DICT0, /* waiting for inflateSetDictionary */
3063 BLOCKS, /* decompressing blocks */
3064 CHECK4, /* four check bytes to go */
3065 CHECK3, /* three check bytes to go */
3066 CHECK2, /* two check bytes to go */
3067 CHECK1, /* one check byte to go */
3068 DONE, /* finished check, done */
3069 BAD} /* got an error--stay here */
3070 mode; /* current inflate mode */
3071
3072 /* mode dependent information */
3073 union {
3074 uInt method; /* if FLAGS, method byte */
3075 struct {
3076 uLong was; /* computed check value */
3077 uLong need; /* stream check value */
3078 } check; /* if CHECK, check values to compare */
3079 uInt marker; /* if BAD, inflateSync's marker bytes count */
3080 } sub; /* submode */
3081
3082 /* mode independent information */
3083 int nowrap; /* flag for no wrapper */
3084 uInt wbits; /* log2(window size) (8..15, defaults to 15) */
3085 inflate_blocks_statef
3086 *blocks; /* current inflate_blocks state */
3087
3088};
3089
3090
3091int inflateReset(z)
3092z_streamp z;
3093{
3094 uLong c;
3095
3096 if (z == Z_NULL || z->state == Z_NULL)
3097 return Z_STREAM_ERROR;
3098 z->total_in = z->total_out = 0;
3099 z->msg = Z_NULL;
3100 z->state->mode = z->state->nowrap ? BLOCKS : METHOD;
3101 inflate_blocks_reset(z->state->blocks, z, &c);
3102 Trace((stderr, "inflate: reset\n"));
3103 return Z_OK;
3104}
3105
3106
3107int inflateEnd(z)
3108z_streamp z;
3109{
3110 uLong c;
3111
3112 if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL)
3113 return Z_STREAM_ERROR;
3114 if (z->state->blocks != Z_NULL)
3115 inflate_blocks_free(z->state->blocks, z, &c);
3116 ZFREE(z, z->state);
3117 z->state = Z_NULL;
3118 Trace((stderr, "inflate: end\n"));
3119 return Z_OK;
3120}
3121
3122
3123int inflateInit2_(z, w, version, stream_size)
3124z_streamp z;
3125int w;
3126const char *version;
3127int stream_size;
3128{
3129 if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
3130 stream_size != sizeof(z_stream))
3131 return Z_VERSION_ERROR;
3132
3133 /* initialize state */
3134 if (z == Z_NULL)
3135 return Z_STREAM_ERROR;
3136 z->msg = Z_NULL;
3137#ifndef NO_ZCFUNCS
3138 if (z->zalloc == Z_NULL)
3139 {
3140 z->zalloc = zcalloc;
3141 z->opaque = (voidpf)0;
3142 }
3143 if (z->zfree == Z_NULL) z->zfree = zcfree;
3144#endif
3145 if ((z->state = (struct internal_state FAR *)
3146 ZALLOC(z,1,sizeof(struct internal_state))) == Z_NULL)
3147 return Z_MEM_ERROR;
3148 z->state->blocks = Z_NULL;
3149
3150 /* handle undocumented nowrap option (no zlib header or check) */
3151 z->state->nowrap = 0;
3152 if (w < 0)
3153 {
3154 w = - w;
3155 z->state->nowrap = 1;
3156 }
3157
3158 /* set window size */
3159 if (w < 8 || w > 15)
3160 {
3161 inflateEnd(z);
3162 return Z_STREAM_ERROR;
3163 }
3164 z->state->wbits = (uInt)w;
3165
3166 /* create inflate_blocks state */
3167 if ((z->state->blocks =
3168 inflate_blocks_new(z, z->state->nowrap ? Z_NULL : adler32, (uInt)1 << w))
3169 == Z_NULL)
3170 {
3171 inflateEnd(z);
3172 return Z_MEM_ERROR;
3173 }
3174 Trace((stderr, "inflate: allocated\n"));
3175
3176 /* reset state */
3177 inflateReset(z);
3178 return Z_OK;
3179}
3180
3181
3182int inflateInit_(z, version, stream_size)
3183z_streamp z;
3184const char *version;
3185int stream_size;
3186{
3187 return inflateInit2_(z, DEF_WBITS, version, stream_size);
3188}
3189
3190
3191#define NEEDBYTE {if(z->avail_in==0)goto empty;r=Z_OK;}
3192#define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++)
3193
3194int inflate(z, f)
3195z_streamp z;
3196int f;
3197{
3198 int r;
3199 uInt b;
3200
3201 if (z == Z_NULL || z->state == Z_NULL || z->next_in == Z_NULL || f < 0)
3202 return Z_STREAM_ERROR;
3203 r = Z_BUF_ERROR;
3204 while (1) switch (z->state->mode)
3205 {
3206 case METHOD:
3207 NEEDBYTE
3208 if (((z->state->sub.method = NEXTBYTE) & 0xf) != Z_DEFLATED)
3209 {
3210 z->state->mode = BAD;
3211 z->msg = (char*)"unknown compression method";
3212 z->state->sub.marker = 5; /* can't try inflateSync */
3213 break;
3214 }
3215 if ((z->state->sub.method >> 4) + 8 > z->state->wbits)
3216 {
3217 z->state->mode = BAD;
3218 z->msg = (char*)"invalid window size";
3219 z->state->sub.marker = 5; /* can't try inflateSync */
3220 break;
3221 }
3222 z->state->mode = FLAG;
3223 case FLAG:
3224 NEEDBYTE
3225 b = NEXTBYTE;
3226 if (((z->state->sub.method << 8) + b) % 31)
3227 {
3228 z->state->mode = BAD;
3229 z->msg = (char*)"incorrect header check";
3230 z->state->sub.marker = 5; /* can't try inflateSync */
3231 break;
3232 }
3233 Trace((stderr, "inflate: zlib header ok\n"));
3234 if (!(b & PRESET_DICT))
3235 {
3236 z->state->mode = BLOCKS;
3237 break;
3238 }
3239 z->state->mode = DICT4;
3240 case DICT4:
3241 NEEDBYTE
3242 z->state->sub.check.need = (uLong)NEXTBYTE << 24;
3243 z->state->mode = DICT3;
3244 case DICT3:
3245 NEEDBYTE
3246 z->state->sub.check.need += (uLong)NEXTBYTE << 16;
3247 z->state->mode = DICT2;
3248 case DICT2:
3249 NEEDBYTE
3250 z->state->sub.check.need += (uLong)NEXTBYTE << 8;
3251 z->state->mode = DICT1;
3252 case DICT1:
3253 NEEDBYTE
3254 z->state->sub.check.need += (uLong)NEXTBYTE;
3255 z->adler = z->state->sub.check.need;
3256 z->state->mode = DICT0;
3257 return Z_NEED_DICT;
3258 case DICT0:
3259 z->state->mode = BAD;
3260 z->msg = (char*)"need dictionary";
3261 z->state->sub.marker = 0; /* can try inflateSync */
3262 return Z_STREAM_ERROR;
3263 case BLOCKS:
3264 r = inflate_blocks(z->state->blocks, z, r);
3265 if (f == Z_PACKET_FLUSH && z->avail_in == 0 && z->avail_out != 0)
3266 r = inflate_packet_flush(z->state->blocks);
3267 if (r == Z_DATA_ERROR)
3268 {
3269 z->state->mode = BAD;
3270 z->state->sub.marker = 0; /* can try inflateSync */
3271 break;
3272 }
3273 if (r != Z_STREAM_END)
3274 return r;
3275 r = Z_OK;
3276 inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was);
3277 if (z->state->nowrap)
3278 {
3279 z->state->mode = DONE;
3280 break;
3281 }
3282 z->state->mode = CHECK4;
3283 case CHECK4:
3284 NEEDBYTE
3285 z->state->sub.check.need = (uLong)NEXTBYTE << 24;
3286 z->state->mode = CHECK3;
3287 case CHECK3:
3288 NEEDBYTE
3289 z->state->sub.check.need += (uLong)NEXTBYTE << 16;
3290 z->state->mode = CHECK2;
3291 case CHECK2:
3292 NEEDBYTE
3293 z->state->sub.check.need += (uLong)NEXTBYTE << 8;
3294 z->state->mode = CHECK1;
3295 case CHECK1:
3296 NEEDBYTE
3297 z->state->sub.check.need += (uLong)NEXTBYTE;
3298
3299 if (z->state->sub.check.was != z->state->sub.check.need)
3300 {
3301 z->state->mode = BAD;
3302 z->msg = (char*)"incorrect data check";
3303 z->state->sub.marker = 5; /* can't try inflateSync */
3304 break;
3305 }
3306 Trace((stderr, "inflate: zlib check ok\n"));
3307 z->state->mode = DONE;
3308 case DONE:
3309 return Z_STREAM_END;
3310 case BAD:
3311 return Z_DATA_ERROR;
3312 default:
3313 return Z_STREAM_ERROR;
3314 }
3315
3316 empty:
3317 if (f != Z_PACKET_FLUSH)
3318 return r;
3319 z->state->mode = BAD;
3320 z->msg = (char *)"need more for packet flush";
3321 z->state->sub.marker = 0; /* can try inflateSync */
3322 return Z_DATA_ERROR;
3323}
3324
3325
3326int inflateSetDictionary(z, dictionary, dictLength)
3327z_streamp z;
3328const Bytef *dictionary;
3329uInt dictLength;
3330{
3331 uInt length = dictLength;
3332
3333 if (z == Z_NULL || z->state == Z_NULL || z->state->mode != DICT0)
3334 return Z_STREAM_ERROR;
3335
3336 if (adler32(1L, dictionary, dictLength) != z->adler) return Z_DATA_ERROR;
3337 z->adler = 1L;
3338
3339 if (length >= ((uInt)1<<z->state->wbits))
3340 {
3341 length = (1<<z->state->wbits)-1;
3342 dictionary += dictLength - length;
3343 }
3344 inflate_set_dictionary(z->state->blocks, dictionary, length);
3345 z->state->mode = BLOCKS;
3346 return Z_OK;
3347}
3348
3349/*
3350 * This subroutine adds the data at next_in/avail_in to the output history
3351 * without performing any output. The output buffer must be "caught up";
3352 * i.e. no pending output (hence s->read equals s->write), and the state must
3353 * be BLOCKS (i.e. we should be willing to see the start of a series of
3354 * BLOCKS). On exit, the output will also be caught up, and the checksum
3355 * will have been updated if need be.
3356 */
3357
3358int inflateIncomp(z)
3359z_stream *z;
3360{
3361 if (z->state->mode != BLOCKS)
3362 return Z_DATA_ERROR;
3363 return inflate_addhistory(z->state->blocks, z);
3364}
3365
3366
3367int inflateSync(z)
3368z_streamp z;
3369{
3370 uInt n; /* number of bytes to look at */
3371 Bytef *p; /* pointer to bytes */
3372 uInt m; /* number of marker bytes found in a row */
3373 uLong r, w; /* temporaries to save total_in and total_out */
3374
3375 /* set up */
3376 if (z == Z_NULL || z->state == Z_NULL)
3377 return Z_STREAM_ERROR;
3378 if (z->state->mode != BAD)
3379 {
3380 z->state->mode = BAD;
3381 z->state->sub.marker = 0;
3382 }
3383 if ((n = z->avail_in) == 0)
3384 return Z_BUF_ERROR;
3385 p = z->next_in;
3386 m = z->state->sub.marker;
3387
3388 /* search */
3389 while (n && m < 4)
3390 {
3391 if (*p == (Byte)(m < 2 ? 0 : 0xff))
3392 m++;
3393 else if (*p)
3394 m = 0;
3395 else
3396 m = 4 - m;
3397 p++, n--;
3398 }
3399
3400 /* restore */
3401 z->total_in += p - z->next_in;
3402 z->next_in = p;
3403 z->avail_in = n;
3404 z->state->sub.marker = m;
3405
3406 /* return no joy or set up to restart on a new block */
3407 if (m != 4)
3408 return Z_DATA_ERROR;
3409 r = z->total_in; w = z->total_out;
3410 inflateReset(z);
3411 z->total_in = r; z->total_out = w;
3412 z->state->mode = BLOCKS;
3413 return Z_OK;
3414}
3415
3416#undef NEEDBYTE
3417#undef NEXTBYTE
3418/* --- inflate.c */
3419
3420/* +++ infblock.c */
3421/* infblock.c -- interpret and process block types to last block
3422 * Copyright (C) 1995-1996 Mark Adler
3423 * For conditions of distribution and use, see copyright notice in zlib.h
3424 */
3425
3426/* #include "zutil.h" */
3427/* #include "infblock.h" */
3428
3429/* +++ inftrees.h */
3430/* inftrees.h -- header to use inftrees.c
3431 * Copyright (C) 1995-1996 Mark Adler
3432 * For conditions of distribution and use, see copyright notice in zlib.h
3433 */
3434
3435/* WARNING: this file should *not* be used by applications. It is
3436 part of the implementation of the compression library and is
3437 subject to change. Applications should only use zlib.h.
3438 */
3439
3440/* Huffman code lookup table entry--this entry is four bytes for machines
3441 that have 16-bit pointers (e.g. PC's in the small or medium model). */
3442
3443typedef struct inflate_huft_s FAR inflate_huft;
3444
3445struct inflate_huft_s {
3446 union {
3447 struct {
3448 Byte Exop; /* number of extra bits or operation */
3449 Byte Bits; /* number of bits in this code or subcode */
3450 } what;
3451 Bytef *pad; /* pad structure to a power of 2 (4 bytes for */
3452 } word; /* 16-bit, 8 bytes for 32-bit machines) */
3453 union {
3454 uInt Base; /* literal, length base, or distance base */
3455 inflate_huft *Next; /* pointer to next level of table */
3456 } more;
3457};
3458
3459#ifdef DEBUG_ZLIB
3460 extern uInt inflate_hufts;
3461#endif
3462
3463extern int inflate_trees_bits OF((
3464 uIntf *, /* 19 code lengths */
3465 uIntf *, /* bits tree desired/actual depth */
3466 inflate_huft * FAR *, /* bits tree result */
3467 z_streamp )); /* for zalloc, zfree functions */
3468
3469extern int inflate_trees_dynamic OF((
3470 uInt, /* number of literal/length codes */
3471 uInt, /* number of distance codes */
3472 uIntf *, /* that many (total) code lengths */
3473 uIntf *, /* literal desired/actual bit depth */
3474 uIntf *, /* distance desired/actual bit depth */
3475 inflate_huft * FAR *, /* literal/length tree result */
3476 inflate_huft * FAR *, /* distance tree result */
3477 z_streamp )); /* for zalloc, zfree functions */
3478
3479extern int inflate_trees_fixed OF((
3480 uIntf *, /* literal desired/actual bit depth */
3481 uIntf *, /* distance desired/actual bit depth */
3482 inflate_huft * FAR *, /* literal/length tree result */
3483 inflate_huft * FAR *)); /* distance tree result */
3484
3485extern int inflate_trees_free OF((
3486 inflate_huft *, /* tables to free */
3487 z_streamp )); /* for zfree function */
3488
3489/* --- inftrees.h */
3490
3491/* +++ infcodes.h */
3492/* infcodes.h -- header to use infcodes.c
3493 * Copyright (C) 1995-1996 Mark Adler
3494 * For conditions of distribution and use, see copyright notice in zlib.h
3495 */
3496
3497/* WARNING: this file should *not* be used by applications. It is
3498 part of the implementation of the compression library and is
3499 subject to change. Applications should only use zlib.h.
3500 */
3501
3502struct inflate_codes_state;
3503typedef struct inflate_codes_state FAR inflate_codes_statef;
3504
3505extern inflate_codes_statef *inflate_codes_new OF((
3506 uInt, uInt,
3507 inflate_huft *, inflate_huft *,
3508 z_streamp ));
3509
3510extern int inflate_codes OF((
3511 inflate_blocks_statef *,
3512 z_streamp ,
3513 int));
3514
3515extern void inflate_codes_free OF((
3516 inflate_codes_statef *,
3517 z_streamp ));
3518
3519/* --- infcodes.h */
3520
3521/* +++ infutil.h */
3522/* infutil.h -- types and macros common to blocks and codes
3523 * Copyright (C) 1995-1996 Mark Adler
3524 * For conditions of distribution and use, see copyright notice in zlib.h
3525 */
3526
3527/* WARNING: this file should *not* be used by applications. It is
3528 part of the implementation of the compression library and is
3529 subject to change. Applications should only use zlib.h.
3530 */
3531
3532#ifndef _INFUTIL_H
3533#define _INFUTIL_H
3534
3535typedef enum {
3536 TYPE, /* get type bits (3, including end bit) */
3537 LENS, /* get lengths for stored */
3538 STORED, /* processing stored block */
3539 TABLE, /* get table lengths */
3540 BTREE, /* get bit lengths tree for a dynamic block */
3541 DTREE, /* get length, distance trees for a dynamic block */
3542 CODES, /* processing fixed or dynamic block */
3543 DRY, /* output remaining window bytes */
3544 DONEB, /* finished last block, done */
3545 BADB} /* got a data error--stuck here */
3546inflate_block_mode;
3547
3548/* inflate blocks semi-private state */
3549struct inflate_blocks_state {
3550
3551 /* mode */
3552 inflate_block_mode mode; /* current inflate_block mode */
3553
3554 /* mode dependent information */
3555 union {
3556 uInt left; /* if STORED, bytes left to copy */
3557 struct {
3558 uInt table; /* table lengths (14 bits) */
3559 uInt index; /* index into blens (or border) */
3560 uIntf *blens; /* bit lengths of codes */
3561 uInt bb; /* bit length tree depth */
3562 inflate_huft *tb; /* bit length decoding tree */
3563 } trees; /* if DTREE, decoding info for trees */
3564 struct {
3565 inflate_huft *tl;
3566 inflate_huft *td; /* trees to free */
3567 inflate_codes_statef
3568 *codes;
3569 } decode; /* if CODES, current state */
3570 } sub; /* submode */
3571 uInt last; /* true if this block is the last block */
3572
3573 /* mode independent information */
3574 uInt bitk; /* bits in bit buffer */
3575 uLong bitb; /* bit buffer */
3576 Bytef *window; /* sliding window */
3577 Bytef *end; /* one byte after sliding window */
3578 Bytef *read; /* window read pointer */
3579 Bytef *write; /* window write pointer */
3580 check_func checkfn; /* check function */
3581 uLong check; /* check on output */
3582
3583};
3584
3585
3586/* defines for inflate input/output */
3587/* update pointers and return */
3588#define UPDBITS {s->bitb=b;s->bitk=k;}
3589#define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;}
3590#define UPDOUT {s->write=q;}
3591#define UPDATE {UPDBITS UPDIN UPDOUT}
3592#define LEAVE {UPDATE return inflate_flush(s,z,r);}
3593/* get bytes and bits */
3594#define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;}
3595#define NEEDBYTE {if(n)r=Z_OK;else LEAVE}
3596#define NEXTBYTE (n--,*p++)
3597#define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}}
3598#define DUMPBITS(j) {b>>=(j);k-=(j);}
3599/* output bytes */
3600#define WAVAIL (uInt)(q<s->read?s->read-q-1:s->end-q)
3601#define LOADOUT {q=s->write;m=(uInt)WAVAIL;}
3602#define WWRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}}
3603#define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT}
3604#define NEEDOUT {if(m==0){WWRAP if(m==0){FLUSH WWRAP if(m==0) LEAVE}}r=Z_OK;}
3605#define OUTBYTE(a) {*q++=(Byte)(a);m--;}
3606/* load local pointers */
3607#define LOAD {LOADIN LOADOUT}
3608
3609/* masks for lower bits (size given to avoid silly warnings with Visual C++) */
3610extern uInt inflate_mask[17];
3611
3612/* copy as much as possible from the sliding window to the output area */
3613extern int inflate_flush OF((
3614 inflate_blocks_statef *,
3615 z_streamp ,
3616 int));
3617
3618#ifndef NO_DUMMY_DECL
3619struct internal_state {int dummy;}; /* for buggy compilers */
3620#endif
3621
3622#endif
3623/* --- infutil.h */
3624
3625#ifndef NO_DUMMY_DECL
3626struct inflate_codes_state {int dummy;}; /* for buggy compilers */
3627#endif
3628
3629/* Table for deflate from PKZIP's appnote.txt. */
3630local const uInt border[] = { /* Order of the bit length code lengths */
3631 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
3632
3633/*
3634 Notes beyond the 1.93a appnote.txt:
3635
3636 1. Distance pointers never point before the beginning of the output
3637 stream.
3638 2. Distance pointers can point back across blocks, up to 32k away.
3639 3. There is an implied maximum of 7 bits for the bit length table and
3640 15 bits for the actual data.
3641 4. If only one code exists, then it is encoded using one bit. (Zero
3642 would be more efficient, but perhaps a little confusing.) If two
3643 codes exist, they are coded using one bit each (0 and 1).
3644 5. There is no way of sending zero distance codes--a dummy must be
3645 sent if there are none. (History: a pre 2.0 version of PKZIP would
3646 store blocks with no distance codes, but this was discovered to be
3647 too harsh a criterion.) Valid only for 1.93a. 2.04c does allow
3648 zero distance codes, which is sent as one code of zero bits in
3649 length.
3650 6. There are up to 286 literal/length codes. Code 256 represents the
3651 end-of-block. Note however that the static length tree defines
3652 288 codes just to fill out the Huffman codes. Codes 286 and 287
3653 cannot be used though, since there is no length base or extra bits
3654 defined for them. Similarily, there are up to 30 distance codes.
3655 However, static trees define 32 codes (all 5 bits) to fill out the
3656 Huffman codes, but the last two had better not show up in the data.
3657 7. Unzip can check dynamic Huffman blocks for complete code sets.
3658 The exception is that a single code would not be complete (see #4).
3659 8. The five bits following the block type is really the number of
3660 literal codes sent minus 257.
3661 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
3662 (1+6+6). Therefore, to output three times the length, you output
3663 three codes (1+1+1), whereas to output four times the same length,
3664 you only need two codes (1+3). Hmm.
3665 10. In the tree reconstruction algorithm, Code = Code + Increment
3666 only if BitLength(i) is not zero. (Pretty obvious.)
3667 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19)
3668 12. Note: length code 284 can represent 227-258, but length code 285
3669 really is 258. The last length deserves its own, short code
3670 since it gets used a lot in very redundant files. The length
3671 258 is special since 258 - 3 (the min match length) is 255.
3672 13. The literal/length and distance code bit lengths are read as a
3673 single stream of lengths. It is possible (and advantageous) for
3674 a repeat code (16, 17, or 18) to go across the boundary between
3675 the two sets of lengths.
3676 */
3677
3678
3679void inflate_blocks_reset(s, z, c)
3680inflate_blocks_statef *s;
3681z_streamp z;
3682uLongf *c;
3683{
3684 if (s->checkfn != Z_NULL)
3685 *c = s->check;
3686 if (s->mode == BTREE || s->mode == DTREE)
3687 ZFREE(z, s->sub.trees.blens);
3688 if (s->mode == CODES)
3689 {
3690 inflate_codes_free(s->sub.decode.codes, z);
3691 inflate_trees_free(s->sub.decode.td, z);
3692 inflate_trees_free(s->sub.decode.tl, z);
3693 }
3694 s->mode = TYPE;
3695 s->bitk = 0;
3696 s->bitb = 0;
3697 s->read = s->write = s->window;
3698 if (s->checkfn != Z_NULL)
3699 z->adler = s->check = (*s->checkfn)(0L, Z_NULL, 0);
3700 Trace((stderr, "inflate: blocks reset\n"));
3701}
3702
3703
3704inflate_blocks_statef *inflate_blocks_new(z, c, w)
3705z_streamp z;
3706check_func c;
3707uInt w;
3708{
3709 inflate_blocks_statef *s;
3710
3711 if ((s = (inflate_blocks_statef *)ZALLOC
3712 (z,1,sizeof(struct inflate_blocks_state))) == Z_NULL)
3713 return s;
3714 if ((s->window = (Bytef *)ZALLOC(z, 1, w)) == Z_NULL)
3715 {
3716 ZFREE(z, s);
3717 return Z_NULL;
3718 }
3719 s->end = s->window + w;
3720 s->checkfn = c;
3721 s->mode = TYPE;
3722 Trace((stderr, "inflate: blocks allocated\n"));
3723 inflate_blocks_reset(s, z, &s->check);
3724 return s;
3725}
3726
3727
3728#ifdef DEBUG_ZLIB
3729 extern uInt inflate_hufts;
3730#endif
3731int inflate_blocks(s, z, r)
3732inflate_blocks_statef *s;
3733z_streamp z;
3734int r;
3735{
3736 uInt t; /* temporary storage */
3737 uLong b; /* bit buffer */
3738 uInt k; /* bits in bit buffer */
3739 Bytef *p; /* input data pointer */
3740 uInt n; /* bytes available there */
3741 Bytef *q; /* output window write pointer */
3742 uInt m; /* bytes to end of window or read pointer */
3743
3744 /* copy input/output information to locals (UPDATE macro restores) */
3745 LOAD
3746
3747 /* process input based on current state */
3748 while (1) switch (s->mode)
3749 {
3750 case TYPE:
3751 NEEDBITS(3)
3752 t = (uInt)b & 7;
3753 s->last = t & 1;
3754 switch (t >> 1)
3755 {
3756 case 0: /* stored */
3757 Trace((stderr, "inflate: stored block%s\n",
3758 s->last ? " (last)" : ""));
3759 DUMPBITS(3)
3760 t = k & 7; /* go to byte boundary */
3761 DUMPBITS(t)
3762 s->mode = LENS; /* get length of stored block */
3763 break;
3764 case 1: /* fixed */
3765 Trace((stderr, "inflate: fixed codes block%s\n",
3766 s->last ? " (last)" : ""));
3767 {
3768 uInt bl, bd;
3769 inflate_huft *tl, *td;
3770
3771 inflate_trees_fixed(&bl, &bd, &tl, &td);
3772 s->sub.decode.codes = inflate_codes_new(bl, bd, tl, td, z);
3773 if (s->sub.decode.codes == Z_NULL)
3774 {
3775 r = Z_MEM_ERROR;
3776 LEAVE
3777 }
3778 s->sub.decode.tl = Z_NULL; /* don't try to free these */
3779 s->sub.decode.td = Z_NULL;
3780 }
3781 DUMPBITS(3)
3782 s->mode = CODES;
3783 break;
3784 case 2: /* dynamic */
3785 Trace((stderr, "inflate: dynamic codes block%s\n",
3786 s->last ? " (last)" : ""));
3787 DUMPBITS(3)
3788 s->mode = TABLE;
3789 break;
3790 case 3: /* illegal */
3791 DUMPBITS(3)
3792 s->mode = BADB;
3793 z->msg = (char*)"invalid block type";
3794 r = Z_DATA_ERROR;
3795 LEAVE
3796 }
3797 break;
3798 case LENS:
3799 NEEDBITS(32)
3800 if ((((~b) >> 16) & 0xffff) != (b & 0xffff))
3801 {
3802 s->mode = BADB;
3803 z->msg = (char*)"invalid stored block lengths";
3804 r = Z_DATA_ERROR;
3805 LEAVE
3806 }
3807 s->sub.left = (uInt)b & 0xffff;
3808 b = k = 0; /* dump bits */
3809 Tracev((stderr, "inflate: stored length %u\n", s->sub.left));
3810 s->mode = s->sub.left ? STORED : (s->last ? DRY : TYPE);
3811 break;
3812 case STORED:
3813 if (n == 0)
3814 LEAVE
3815 NEEDOUT
3816 t = s->sub.left;
3817 if (t > n) t = n;
3818 if (t > m) t = m;
3819 zmemcpy(q, p, t);
3820 p += t; n -= t;
3821 q += t; m -= t;
3822 if ((s->sub.left -= t) != 0)
3823 break;
3824 Tracev((stderr, "inflate: stored end, %lu total out\n",
3825 z->total_out + (q >= s->read ? q - s->read :
3826 (s->end - s->read) + (q - s->window))));
3827 s->mode = s->last ? DRY : TYPE;
3828 break;
3829 case TABLE:
3830 NEEDBITS(14)
3831 s->sub.trees.table = t = (uInt)b & 0x3fff;
3832#ifndef PKZIP_BUG_WORKAROUND
3833 if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29)
3834 {
3835 s->mode = BADB;
3836 z->msg = (char*)"too many length or distance symbols";
3837 r = Z_DATA_ERROR;
3838 LEAVE
3839 }
3840#endif
3841 t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
3842 if (t < 19)
3843 t = 19;
3844 if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL)
3845 {
3846 r = Z_MEM_ERROR;
3847 LEAVE
3848 }
3849 DUMPBITS(14)
3850 s->sub.trees.index = 0;
3851 Tracev((stderr, "inflate: table sizes ok\n"));
3852 s->mode = BTREE;
3853 case BTREE:
3854 while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10))
3855 {
3856 NEEDBITS(3)
3857 s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7;
3858 DUMPBITS(3)
3859 }
3860 while (s->sub.trees.index < 19)
3861 s->sub.trees.blens[border[s->sub.trees.index++]] = 0;
3862 s->sub.trees.bb = 7;
3863 t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb,
3864 &s->sub.trees.tb, z);
3865 if (t != Z_OK)
3866 {
3867 ZFREE(z, s->sub.trees.blens);
3868 r = t;
3869 if (r == Z_DATA_ERROR)
3870 s->mode = BADB;
3871 LEAVE
3872 }
3873 s->sub.trees.index = 0;
3874 Tracev((stderr, "inflate: bits tree ok\n"));
3875 s->mode = DTREE;
3876 case DTREE:
3877 while (t = s->sub.trees.table,
3878 s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f))
3879 {
3880 inflate_huft *h;
3881 uInt i, j, c;
3882
3883 t = s->sub.trees.bb;
3884 NEEDBITS(t)
3885 h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]);
3886 t = h->word.what.Bits;
3887 c = h->more.Base;
3888 if (c < 16)
3889 {
3890 DUMPBITS(t)
3891 s->sub.trees.blens[s->sub.trees.index++] = c;
3892 }
3893 else /* c == 16..18 */
3894 {
3895 i = c == 18 ? 7 : c - 14;
3896 j = c == 18 ? 11 : 3;
3897 NEEDBITS(t + i)
3898 DUMPBITS(t)
3899 j += (uInt)b & inflate_mask[i];
3900 DUMPBITS(i)
3901 i = s->sub.trees.index;
3902 t = s->sub.trees.table;
3903 if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) ||
3904 (c == 16 && i < 1))
3905 {
3906 inflate_trees_free(s->sub.trees.tb, z);
3907 ZFREE(z, s->sub.trees.blens);
3908 s->mode = BADB;
3909 z->msg = (char*)"invalid bit length repeat";
3910 r = Z_DATA_ERROR;
3911 LEAVE
3912 }
3913 c = c == 16 ? s->sub.trees.blens[i - 1] : 0;
3914 do {
3915 s->sub.trees.blens[i++] = c;
3916 } while (--j);
3917 s->sub.trees.index = i;
3918 }
3919 }
3920 inflate_trees_free(s->sub.trees.tb, z);
3921 s->sub.trees.tb = Z_NULL;
3922 {
3923 uInt bl, bd;
3924 inflate_huft *tl, *td;
3925 inflate_codes_statef *c;
3926
3927 bl = 9; /* must be <= 9 for lookahead assumptions */
3928 bd = 6; /* must be <= 9 for lookahead assumptions */
3929 t = s->sub.trees.table;
3930#ifdef DEBUG_ZLIB
3931 inflate_hufts = 0;
3932#endif
3933 t = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f),
3934 s->sub.trees.blens, &bl, &bd, &tl, &td, z);
3935 ZFREE(z, s->sub.trees.blens);
3936 if (t != Z_OK)
3937 {
3938 if (t == (uInt)Z_DATA_ERROR)
3939 s->mode = BADB;
3940 r = t;
3941 LEAVE
3942 }
3943 Tracev((stderr, "inflate: trees ok, %d * %d bytes used\n",
3944 inflate_hufts, sizeof(inflate_huft)));
3945 if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL)
3946 {
3947 inflate_trees_free(td, z);
3948 inflate_trees_free(tl, z);
3949 r = Z_MEM_ERROR;
3950 LEAVE
3951 }
3952 s->sub.decode.codes = c;
3953 s->sub.decode.tl = tl;
3954 s->sub.decode.td = td;
3955 }
3956 s->mode = CODES;
3957 case CODES:
3958 UPDATE
3959 if ((r = inflate_codes(s, z, r)) != Z_STREAM_END)
3960 return inflate_flush(s, z, r);
3961 r = Z_OK;
3962 inflate_codes_free(s->sub.decode.codes, z);
3963 inflate_trees_free(s->sub.decode.td, z);
3964 inflate_trees_free(s->sub.decode.tl, z);
3965 LOAD
3966 Tracev((stderr, "inflate: codes end, %lu total out\n",
3967 z->total_out + (q >= s->read ? q - s->read :
3968 (s->end - s->read) + (q - s->window))));
3969 if (!s->last)
3970 {
3971 s->mode = TYPE;
3972 break;
3973 }
3974 if (k > 7) /* return unused byte, if any */
3975 {
3976 Assert(k < 16, "inflate_codes grabbed too many bytes")
3977 k -= 8;
3978 n++;
3979 p--; /* can always return one */
3980 }
3981 s->mode = DRY;
3982 case DRY:
3983 FLUSH
3984 if (s->read != s->write)
3985 LEAVE
3986 s->mode = DONEB;
3987 case DONEB:
3988 r = Z_STREAM_END;
3989 LEAVE
3990 case BADB:
3991 r = Z_DATA_ERROR;
3992 LEAVE
3993 default:
3994 r = Z_STREAM_ERROR;
3995 LEAVE
3996 }
3997}
3998
3999
4000int inflate_blocks_free(s, z, c)
4001inflate_blocks_statef *s;
4002z_streamp z;
4003uLongf *c;
4004{
4005 inflate_blocks_reset(s, z, c);
4006 ZFREE(z, s->window);
4007 ZFREE(z, s);
4008 Trace((stderr, "inflate: blocks freed\n"));
4009 return Z_OK;
4010}
4011
4012
4013void inflate_set_dictionary(s, d, n)
4014inflate_blocks_statef *s;
4015const Bytef *d;
4016uInt n;
4017{
4018 zmemcpy((charf *)s->window, d, n);
4019 s->read = s->write = s->window + n;
4020}
4021
4022/*
4023 * This subroutine adds the data at next_in/avail_in to the output history
4024 * without performing any output. The output buffer must be "caught up";
4025 * i.e. no pending output (hence s->read equals s->write), and the state must
4026 * be BLOCKS (i.e. we should be willing to see the start of a series of
4027 * BLOCKS). On exit, the output will also be caught up, and the checksum
4028 * will have been updated if need be.
4029 */
4030int inflate_addhistory(s, z)
4031inflate_blocks_statef *s;
4032z_stream *z;
4033{
4034 uLong b; /* bit buffer */ /* NOT USED HERE */
4035 uInt k; /* bits in bit buffer */ /* NOT USED HERE */
4036 uInt t; /* temporary storage */
4037 Bytef *p; /* input data pointer */
4038 uInt n; /* bytes available there */
4039 Bytef *q; /* output window write pointer */
4040 uInt m; /* bytes to end of window or read pointer */
4041
4042 if (s->read != s->write)
4043 return Z_STREAM_ERROR;
4044 if (s->mode != TYPE)
4045 return Z_DATA_ERROR;
4046
4047 /* we're ready to rock */
4048 LOAD
4049 /* while there is input ready, copy to output buffer, moving
4050 * pointers as needed.
4051 */
4052 while (n) {
4053 t = n; /* how many to do */
4054 /* is there room until end of buffer? */
4055 if (t > m) t = m;
4056 /* update check information */
4057 if (s->checkfn != Z_NULL)
4058 s->check = (*s->checkfn)(s->check, q, t);
4059 zmemcpy(q, p, t);
4060 q += t;
4061 p += t;
4062 n -= t;
4063 z->total_out += t;
4064 s->read = q; /* drag read pointer forward */
4065/* WWRAP */ /* expand WWRAP macro by hand to handle s->read */
4066 if (q == s->end) {
4067 s->read = q = s->window;
4068 m = WAVAIL;
4069 }
4070 }
4071 UPDATE
4072 return Z_OK;
4073}
4074
4075
4076/*
4077 * At the end of a Deflate-compressed PPP packet, we expect to have seen
4078 * a `stored' block type value but not the (zero) length bytes.
4079 */
4080int inflate_packet_flush(s)
4081 inflate_blocks_statef *s;
4082{
4083 if (s->mode != LENS)
4084 return Z_DATA_ERROR;
4085 s->mode = TYPE;
4086 return Z_OK;
4087}
4088/* --- infblock.c */
4089
4090/* +++ inftrees.c */
4091/* inftrees.c -- generate Huffman trees for efficient decoding
4092 * Copyright (C) 1995-1996 Mark Adler
4093 * For conditions of distribution and use, see copyright notice in zlib.h
4094 */
4095
4096/* #include "zutil.h" */
4097/* #include "inftrees.h" */
4098
4099char inflate_copyright[] = " inflate 1.0.4 Copyright 1995-1996 Mark Adler ";
4100/*
4101 If you use the zlib library in a product, an acknowledgment is welcome
4102 in the documentation of your product. If for some reason you cannot
4103 include such an acknowledgment, I would appreciate that you keep this
4104 copyright string in the executable of your product.
4105 */
4106
4107#ifndef NO_DUMMY_DECL
4108struct internal_state {int dummy;}; /* for buggy compilers */
4109#endif
4110
4111/* simplify the use of the inflate_huft type with some defines */
4112#define base more.Base
4113#define next more.Next
4114#define exop word.what.Exop
4115#define bits word.what.Bits
4116
4117
4118local int huft_build OF((
4119 uIntf *, /* code lengths in bits */
4120 uInt, /* number of codes */
4121 uInt, /* number of "simple" codes */
4122 const uIntf *, /* list of base values for non-simple codes */
4123 const uIntf *, /* list of extra bits for non-simple codes */
4124 inflate_huft * FAR*,/* result: starting table */
4125 uIntf *, /* maximum lookup bits (returns actual) */
4126 z_streamp )); /* for zalloc function */
4127
4128local voidpf falloc OF((
4129 voidpf, /* opaque pointer (not used) */
4130 uInt, /* number of items */
4131 uInt)); /* size of item */
4132
4133/* Tables for deflate from PKZIP's appnote.txt. */
4134local const uInt cplens[31] = { /* Copy lengths for literal codes 257..285 */
4135 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
4136 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
4137 /* see note #13 above about 258 */
4138local const uInt cplext[31] = { /* Extra bits for literal codes 257..285 */
4139 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
4140 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 112, 112}; /* 112==invalid */
4141local const uInt cpdist[30] = { /* Copy offsets for distance codes 0..29 */
4142 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
4143 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
4144 8193, 12289, 16385, 24577};
4145local const uInt cpdext[30] = { /* Extra bits for distance codes */
4146 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
4147 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
4148 12, 12, 13, 13};
4149
4150/*
4151 Huffman code decoding is performed using a multi-level table lookup.
4152 The fastest way to decode is to simply build a lookup table whose
4153 size is determined by the longest code. However, the time it takes
4154 to build this table can also be a factor if the data being decoded
4155 is not very long. The most common codes are necessarily the
4156 shortest codes, so those codes dominate the decoding time, and hence
4157 the speed. The idea is you can have a shorter table that decodes the
4158 shorter, more probable codes, and then point to subsidiary tables for
4159 the longer codes. The time it costs to decode the longer codes is
4160 then traded against the time it takes to make longer tables.
4161
4162 This results of this trade are in the variables lbits and dbits
4163 below. lbits is the number of bits the first level table for literal/
4164 length codes can decode in one step, and dbits is the same thing for
4165 the distance codes. Subsequent tables are also less than or equal to
4166 those sizes. These values may be adjusted either when all of the
4167 codes are shorter than that, in which case the longest code length in
4168 bits is used, or when the shortest code is *longer* than the requested
4169 table size, in which case the length of the shortest code in bits is
4170 used.
4171
4172 There are two different values for the two tables, since they code a
4173 different number of possibilities each. The literal/length table
4174 codes 286 possible values, or in a flat code, a little over eight
4175 bits. The distance table codes 30 possible values, or a little less
4176 than five bits, flat. The optimum values for speed end up being
4177 about one bit more than those, so lbits is 8+1 and dbits is 5+1.
4178 The optimum values may differ though from machine to machine, and
4179 possibly even between compilers. Your mileage may vary.
4180 */
4181
4182
4183/* If BMAX needs to be larger than 16, then h and x[] should be uLong. */
4184#define BMAX 15 /* maximum bit length of any code */
4185#define N_MAX 288 /* maximum number of codes in any set */
4186
4187#ifdef DEBUG_ZLIB
4188 uInt inflate_hufts;
4189#endif
4190
4191local int huft_build(b, n, s, d, e, t, m, zs)
4192uIntf *b; /* code lengths in bits (all assumed <= BMAX) */
4193uInt n; /* number of codes (assumed <= N_MAX) */
4194uInt s; /* number of simple-valued codes (0..s-1) */
4195const uIntf *d; /* list of base values for non-simple codes */
4196const uIntf *e; /* list of extra bits for non-simple codes */
4197inflate_huft * FAR *t; /* result: starting table */
4198uIntf *m; /* maximum lookup bits, returns actual */
4199z_streamp zs; /* for zalloc function */
4200/* Given a list of code lengths and a maximum table size, make a set of
4201 tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR
4202 if the given code set is incomplete (the tables are still built in this
4203 case), Z_DATA_ERROR if the input is invalid (an over-subscribed set of
4204 lengths), or Z_MEM_ERROR if not enough memory. */
4205{
4206
4207 uInt a; /* counter for codes of length k */
4208 uInt c[BMAX+1]; /* bit length count table */
4209 uInt f; /* i repeats in table every f entries */
4210 int g; /* maximum code length */
4211 int h; /* table level */
4212 register uInt i; /* counter, current code */
4213 register uInt j; /* counter */
4214 register int k; /* number of bits in current code */
4215 int l; /* bits per table (returned in m) */
4216 register uIntf *p; /* pointer into c[], b[], or v[] */
4217 inflate_huft *q; /* points to current table */
4218 struct inflate_huft_s r; /* table entry for structure assignment */
4219 inflate_huft *u[BMAX]; /* table stack */
4220 uInt v[N_MAX]; /* values in order of bit length */
4221 register int w; /* bits before this table == (l * h) */
4222 uInt x[BMAX+1]; /* bit offsets, then code stack */
4223 uIntf *xp; /* pointer into x */
4224 int y; /* number of dummy codes added */
4225 uInt z; /* number of entries in current table */
4226
4227
4228 /* Generate counts for each bit length */
4229 p = c;
4230#define C0 *p++ = 0;
4231#define C2 C0 C0 C0 C0
4232#define C4 C2 C2 C2 C2
4233 C4 /* clear c[]--assume BMAX+1 is 16 */
4234 p = b; i = n;
4235 do {
4236 c[*p++]++; /* assume all entries <= BMAX */
4237 } while (--i);
4238 if (c[0] == n) /* null input--all zero length codes */
4239 {
4240 *t = (inflate_huft *)Z_NULL;
4241 *m = 0;
4242 return Z_OK;
4243 }
4244
4245
4246 /* Find minimum and maximum length, bound *m by those */
4247 l = *m;
4248 for (j = 1; j <= BMAX; j++)
4249 if (c[j])
4250 break;
4251 k = j; /* minimum code length */
4252 if ((uInt)l < j)
4253 l = j;
4254 for (i = BMAX; i; i--)
4255 if (c[i])
4256 break;
4257 g = i; /* maximum code length */
4258 if ((uInt)l > i)
4259 l = i;
4260 *m = l;
4261
4262
4263 /* Adjust last length count to fill out codes, if needed */
4264 for (y = 1 << j; j < i; j++, y <<= 1)
4265 if ((y -= c[j]) < 0)
4266 return Z_DATA_ERROR;
4267 if ((y -= c[i]) < 0)
4268 return Z_DATA_ERROR;
4269 c[i] += y;
4270
4271
4272 /* Generate starting offsets into the value table for each length */
4273 x[1] = j = 0;
4274 p = c + 1; xp = x + 2;
4275 while (--i) { /* note that i == g from above */
4276 *xp++ = (j += *p++);
4277 }
4278
4279
4280 /* Make a table of values in order of bit lengths */
4281 p = b; i = 0;
4282 do {
4283 if ((j = *p++) != 0)
4284 v[x[j]++] = i;
4285 } while (++i < n);
4286 n = x[g]; /* set n to length of v */
4287
4288
4289 /* Generate the Huffman codes and for each, make the table entries */
4290 x[0] = i = 0; /* first Huffman code is zero */
4291 p = v; /* grab values in bit order */
4292 h = -1; /* no tables yet--level -1 */
4293 w = -l; /* bits decoded == (l * h) */
4294 u[0] = (inflate_huft *)Z_NULL; /* just to keep compilers happy */
4295 q = (inflate_huft *)Z_NULL; /* ditto */
4296 z = 0; /* ditto */
4297
4298 /* go through the bit lengths (k already is bits in shortest code) */
4299 for (; k <= g; k++)
4300 {
4301 a = c[k];
4302 while (a--)
4303 {
4304 /* here i is the Huffman code of length k bits for value *p */
4305 /* make tables up to required level */
4306 while (k > w + l)
4307 {
4308 h++;
4309 w += l; /* previous table always l bits */
4310
4311 /* compute minimum size table less than or equal to l bits */
4312 z = g - w;
4313 z = z > (uInt)l ? l : z; /* table size upper limit */
4314 if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */
4315 { /* too few codes for k-w bit table */
4316 f -= a + 1; /* deduct codes from patterns left */
4317 xp = c + k;
4318 if (j < z)
4319 while (++j < z) /* try smaller tables up to z bits */
4320 {
4321 if ((f <<= 1) <= *++xp)
4322 break; /* enough codes to use up j bits */
4323 f -= *xp; /* else deduct codes from patterns */
4324 }
4325 }
4326 z = 1 << j; /* table entries for j-bit table */
4327
4328 /* allocate and link in new table */
4329 if ((q = (inflate_huft *)ZALLOC
4330 (zs,z + 1,sizeof(inflate_huft))) == Z_NULL)
4331 {
4332 if (h)
4333 inflate_trees_free(u[0], zs);
4334 return Z_MEM_ERROR; /* not enough memory */
4335 }
4336#ifdef DEBUG_ZLIB
4337 inflate_hufts += z + 1;
4338#endif
4339 *t = q + 1; /* link to list for huft_free() */
4340 *(t = &(q->next)) = Z_NULL;
4341 u[h] = ++q; /* table starts after link */
4342
4343 /* connect to last table, if there is one */
4344 if (h)
4345 {
4346 x[h] = i; /* save pattern for backing up */
4347 r.bits = (Byte)l; /* bits to dump before this table */
4348 r.exop = (Byte)j; /* bits in this table */
4349 r.next = q; /* pointer to this table */
4350 j = i >> (w - l); /* (get around Turbo C bug) */
4351 u[h-1][j] = r; /* connect to last table */
4352 }
4353 }
4354
4355 /* set up table entry in r */
4356 r.bits = (Byte)(k - w);
4357 if (p >= v + n)
4358 r.exop = 128 + 64; /* out of values--invalid code */
4359 else if (*p < s)
4360 {
4361 r.exop = (Byte)(*p < 256 ? 0 : 32 + 64); /* 256 is end-of-block */
4362 r.base = *p++; /* simple code is just the value */
4363 }
4364 else
4365 {
4366 r.exop = (Byte)(e[*p - s] + 16 + 64);/* non-simple--look up in lists */
4367 r.base = d[*p++ - s];
4368 }
4369
4370 /* fill code-like entries with r */
4371 f = 1 << (k - w);
4372 for (j = i >> w; j < z; j += f)
4373 q[j] = r;
4374
4375 /* backwards increment the k-bit code i */
4376 for (j = 1 << (k - 1); i & j; j >>= 1)
4377 i ^= j;
4378 i ^= j;
4379
4380 /* backup over finished tables */
4381 while ((i & ((1 << w) - 1)) != x[h])
4382 {
4383 h--; /* don't need to update q */
4384 w -= l;
4385 }
4386 }
4387 }
4388
4389
4390 /* Return Z_BUF_ERROR if we were given an incomplete table */
4391 return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK;
4392}
4393
4394
4395int inflate_trees_bits(c, bb, tb, z)
4396uIntf *c; /* 19 code lengths */
4397uIntf *bb; /* bits tree desired/actual depth */
4398inflate_huft * FAR *tb; /* bits tree result */
4399z_streamp z; /* for zfree function */
4400{
4401 int r;
4402
4403 r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL, tb, bb, z);
4404 if (r == Z_DATA_ERROR)
4405 z->msg = (char*)"oversubscribed dynamic bit lengths tree";
4406 else if (r == Z_BUF_ERROR || *bb == 0)
4407 {
4408 inflate_trees_free(*tb, z);
4409 z->msg = (char*)"incomplete dynamic bit lengths tree";
4410 r = Z_DATA_ERROR;
4411 }
4412 return r;
4413}
4414
4415
4416int inflate_trees_dynamic(nl, nd, c, bl, bd, tl, td, z)
4417uInt nl; /* number of literal/length codes */
4418uInt nd; /* number of distance codes */
4419uIntf *c; /* that many (total) code lengths */
4420uIntf *bl; /* literal desired/actual bit depth */
4421uIntf *bd; /* distance desired/actual bit depth */
4422inflate_huft * FAR *tl; /* literal/length tree result */
4423inflate_huft * FAR *td; /* distance tree result */
4424z_streamp z; /* for zfree function */
4425{
4426 int r;
4427
4428 /* build literal/length tree */
4429 r = huft_build(c, nl, 257, cplens, cplext, tl, bl, z);
4430 if (r != Z_OK || *bl == 0)
4431 {
4432 if (r == Z_DATA_ERROR)
4433 z->msg = (char*)"oversubscribed literal/length tree";
4434 else if (r != Z_MEM_ERROR)
4435 {
4436 inflate_trees_free(*tl, z);
4437 z->msg = (char*)"incomplete literal/length tree";
4438 r = Z_DATA_ERROR;
4439 }
4440 return r;
4441 }
4442
4443 /* build distance tree */
4444 r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, z);
4445 if (r != Z_OK || (*bd == 0 && nl > 257))
4446 {
4447 if (r == Z_DATA_ERROR)
4448 z->msg = (char*)"oversubscribed distance tree";
4449 else if (r == Z_BUF_ERROR) {
4450#ifdef PKZIP_BUG_WORKAROUND
4451 r = Z_OK;
4452 }
4453#else
4454 inflate_trees_free(*td, z);
4455 z->msg = (char*)"incomplete distance tree";
4456 r = Z_DATA_ERROR;
4457 }
4458 else if (r != Z_MEM_ERROR)
4459 {
4460 z->msg = (char*)"empty distance tree with lengths";
4461 r = Z_DATA_ERROR;
4462 }
4463 inflate_trees_free(*tl, z);
4464 return r;
4465#endif
4466 }
4467
4468 /* done */
4469 return Z_OK;
4470}
4471
4472
4473/* build fixed tables only once--keep them here */
4474local int fixed_built = 0;
4475#define FIXEDH 530 /* number of hufts used by fixed tables */
4476local inflate_huft fixed_mem[FIXEDH];
4477local uInt fixed_bl;
4478local uInt fixed_bd;
4479local inflate_huft *fixed_tl;
4480local inflate_huft *fixed_td;
4481
4482
4483local voidpf falloc(q, n, s)
4484voidpf q; /* opaque pointer */
4485uInt n; /* number of items */
4486uInt s; /* size of item */
4487{
4488 Assert(s == sizeof(inflate_huft) && n <= *(intf *)q,
4489 "inflate_trees falloc overflow");
4490 *(intf *)q -= n+s-s; /* s-s to avoid warning */
4491 return (voidpf)(fixed_mem + *(intf *)q);
4492}
4493
4494
4495int inflate_trees_fixed(bl, bd, tl, td)
4496uIntf *bl; /* literal desired/actual bit depth */
4497uIntf *bd; /* distance desired/actual bit depth */
4498inflate_huft * FAR *tl; /* literal/length tree result */
4499inflate_huft * FAR *td; /* distance tree result */
4500{
4501 /* build fixed tables if not already (multiple overlapped executions ok) */
4502 if (!fixed_built)
4503 {
4504 int k; /* temporary variable */
4505 unsigned c[288]; /* length list for huft_build */
4506 z_stream z; /* for falloc function */
4507 int f = FIXEDH; /* number of hufts left in fixed_mem */
4508
4509 /* set up fake z_stream for memory routines */
4510 z.zalloc = falloc;
4511 z.zfree = Z_NULL;
4512 z.opaque = (voidpf)&f;
4513
4514 /* literal table */
4515 for (k = 0; k < 144; k++)
4516 c[k] = 8;
4517 for (; k < 256; k++)
4518 c[k] = 9;
4519 for (; k < 280; k++)
4520 c[k] = 7;
4521 for (; k < 288; k++)
4522 c[k] = 8;
4523 fixed_bl = 7;
4524 huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl, &z);
4525
4526 /* distance table */
4527 for (k = 0; k < 30; k++)
4528 c[k] = 5;
4529 fixed_bd = 5;
4530 huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd, &z);
4531
4532 /* done */
4533 Assert(f == 0, "invalid build of fixed tables");
4534 fixed_built = 1;
4535 }
4536 *bl = fixed_bl;
4537 *bd = fixed_bd;
4538 *tl = fixed_tl;
4539 *td = fixed_td;
4540 return Z_OK;
4541}
4542
4543
4544int inflate_trees_free(t, z)
4545inflate_huft *t; /* table to free */
4546z_streamp z; /* for zfree function */
4547/* Free the malloc'ed tables built by huft_build(), which makes a linked
4548 list of the tables it made, with the links in a dummy first entry of
4549 each table. */
4550{
4551 register inflate_huft *p, *q, *r;
4552
4553 /* Reverse linked list */
4554 p = Z_NULL;
4555 q = t;
4556 while (q != Z_NULL)
4557 {
4558 r = (q - 1)->next;
4559 (q - 1)->next = p;
4560 p = q;
4561 q = r;
4562 }
4563 /* Go through linked list, freeing from the malloced (t[-1]) address. */
4564 while (p != Z_NULL)
4565 {
4566 q = (--p)->next;
4567 ZFREE(z,p);
4568 p = q;
4569 }
4570 return Z_OK;
4571}
4572/* --- inftrees.c */
4573
4574/* +++ infcodes.c */
4575/* infcodes.c -- process literals and length/distance pairs
4576 * Copyright (C) 1995-1996 Mark Adler
4577 * For conditions of distribution and use, see copyright notice in zlib.h
4578 */
4579
4580/* #include "zutil.h" */
4581/* #include "inftrees.h" */
4582/* #include "infblock.h" */
4583/* #include "infcodes.h" */
4584/* #include "infutil.h" */
4585
4586/* +++ inffast.h */
4587/* inffast.h -- header to use inffast.c
4588 * Copyright (C) 1995-1996 Mark Adler
4589 * For conditions of distribution and use, see copyright notice in zlib.h
4590 */
4591
4592/* WARNING: this file should *not* be used by applications. It is
4593 part of the implementation of the compression library and is
4594 subject to change. Applications should only use zlib.h.
4595 */
4596
4597extern int inflate_fast OF((
4598 uInt,
4599 uInt,
4600 inflate_huft *,
4601 inflate_huft *,
4602 inflate_blocks_statef *,
4603 z_streamp ));
4604/* --- inffast.h */
4605
4606/* simplify the use of the inflate_huft type with some defines */
4607#define base more.Base
4608#define next more.Next
4609#define exop word.what.Exop
4610#define bits word.what.Bits
4611
4612/* inflate codes private state */
4613struct inflate_codes_state {
4614
4615 /* mode */
4616 enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
4617 START, /* x: set up for LEN */
4618 LEN, /* i: get length/literal/eob next */
4619 LENEXT, /* i: getting length extra (have base) */
4620 DIST, /* i: get distance next */
4621 DISTEXT, /* i: getting distance extra */
4622 COPY, /* o: copying bytes in window, waiting for space */
4623 LIT, /* o: got literal, waiting for output space */
4624 WASH, /* o: got eob, possibly still output waiting */
4625 END, /* x: got eob and all data flushed */
4626 BADCODE} /* x: got error */
4627 mode; /* current inflate_codes mode */
4628
4629 /* mode dependent information */
4630 uInt len;
4631 union {
4632 struct {
4633 inflate_huft *tree; /* pointer into tree */
4634 uInt need; /* bits needed */
4635 } code; /* if LEN or DIST, where in tree */
4636 uInt lit; /* if LIT, literal */
4637 struct {
4638 uInt get; /* bits to get for extra */
4639 uInt dist; /* distance back to copy from */
4640 } copy; /* if EXT or COPY, where and how much */
4641 } sub; /* submode */
4642
4643 /* mode independent information */
4644 Byte lbits; /* ltree bits decoded per branch */
4645 Byte dbits; /* dtree bits decoder per branch */
4646 inflate_huft *ltree; /* literal/length/eob tree */
4647 inflate_huft *dtree; /* distance tree */
4648
4649};
4650
4651
4652inflate_codes_statef *inflate_codes_new(bl, bd, tl, td, z)
4653uInt bl, bd;
4654inflate_huft *tl;
4655inflate_huft *td; /* need separate declaration for Borland C++ */
4656z_streamp z;
4657{
4658 inflate_codes_statef *c;
4659
4660 if ((c = (inflate_codes_statef *)
4661 ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL)
4662 {
4663 c->mode = START;
4664 c->lbits = (Byte)bl;
4665 c->dbits = (Byte)bd;
4666 c->ltree = tl;
4667 c->dtree = td;
4668 Tracev((stderr, "inflate: codes new\n"));
4669 }
4670 return c;
4671}
4672
4673
4674int inflate_codes(s, z, r)
4675inflate_blocks_statef *s;
4676z_streamp z;
4677int r;
4678{
4679 uInt j; /* temporary storage */
4680 inflate_huft *t; /* temporary pointer */
4681 uInt e; /* extra bits or operation */
4682 uLong b; /* bit buffer */
4683 uInt k; /* bits in bit buffer */
4684 Bytef *p; /* input data pointer */
4685 uInt n; /* bytes available there */
4686 Bytef *q; /* output window write pointer */
4687 uInt m; /* bytes to end of window or read pointer */
4688 Bytef *f; /* pointer to copy strings from */
4689 inflate_codes_statef *c = s->sub.decode.codes; /* codes state */
4690
4691 /* copy input/output information to locals (UPDATE macro restores) */
4692 LOAD
4693
4694 /* process input and output based on current state */
4695 while (1) switch (c->mode)
4696 { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
4697 case START: /* x: set up for LEN */
4698#ifndef SLOW
4699 if (m >= 258 && n >= 10)
4700 {
4701 UPDATE
4702 r = inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z);
4703 LOAD
4704 if (r != Z_OK)
4705 {
4706 c->mode = r == Z_STREAM_END ? WASH : BADCODE;
4707 break;
4708 }
4709 }
4710#endif /* !SLOW */
4711 c->sub.code.need = c->lbits;
4712 c->sub.code.tree = c->ltree;
4713 c->mode = LEN;
4714 case LEN: /* i: get length/literal/eob next */
4715 j = c->sub.code.need;
4716 NEEDBITS(j)
4717 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
4718 DUMPBITS(t->bits)
4719 e = (uInt)(t->exop);
4720 if (e == 0) /* literal */
4721 {
4722 c->sub.lit = t->base;
4723 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
4724 "inflate: literal '%c'\n" :
4725 "inflate: literal 0x%02x\n", t->base));
4726 c->mode = LIT;
4727 break;
4728 }
4729 if (e & 16) /* length */
4730 {
4731 c->sub.copy.get = e & 15;
4732 c->len = t->base;
4733 c->mode = LENEXT;
4734 break;
4735 }
4736 if ((e & 64) == 0) /* next table */
4737 {
4738 c->sub.code.need = e;
4739 c->sub.code.tree = t->next;
4740 break;
4741 }
4742 if (e & 32) /* end of block */
4743 {
4744 Tracevv((stderr, "inflate: end of block\n"));
4745 c->mode = WASH;
4746 break;
4747 }
4748 c->mode = BADCODE; /* invalid code */
4749 z->msg = (char*)"invalid literal/length code";
4750 r = Z_DATA_ERROR;
4751 LEAVE
4752 case LENEXT: /* i: getting length extra (have base) */
4753 j = c->sub.copy.get;
4754 NEEDBITS(j)
4755 c->len += (uInt)b & inflate_mask[j];
4756 DUMPBITS(j)
4757 c->sub.code.need = c->dbits;
4758 c->sub.code.tree = c->dtree;
4759 Tracevv((stderr, "inflate: length %u\n", c->len));
4760 c->mode = DIST;
4761 case DIST: /* i: get distance next */
4762 j = c->sub.code.need;
4763 NEEDBITS(j)
4764 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
4765 DUMPBITS(t->bits)
4766 e = (uInt)(t->exop);
4767 if (e & 16) /* distance */
4768 {
4769 c->sub.copy.get = e & 15;
4770 c->sub.copy.dist = t->base;
4771 c->mode = DISTEXT;
4772 break;
4773 }
4774 if ((e & 64) == 0) /* next table */
4775 {
4776 c->sub.code.need = e;
4777 c->sub.code.tree = t->next;
4778 break;
4779 }
4780 c->mode = BADCODE; /* invalid code */
4781 z->msg = (char*)"invalid distance code";
4782 r = Z_DATA_ERROR;
4783 LEAVE
4784 case DISTEXT: /* i: getting distance extra */
4785 j = c->sub.copy.get;
4786 NEEDBITS(j)
4787 c->sub.copy.dist += (uInt)b & inflate_mask[j];
4788 DUMPBITS(j)
4789 Tracevv((stderr, "inflate: distance %u\n", c->sub.copy.dist));
4790 c->mode = COPY;
4791 case COPY: /* o: copying bytes in window, waiting for space */
4792#ifndef __TURBOC__ /* Turbo C bug for following expression */
4793 f = (uInt)(q - s->window) < c->sub.copy.dist ?
4794 s->end - (c->sub.copy.dist - (q - s->window)) :
4795 q - c->sub.copy.dist;
4796#else
4797 f = q - c->sub.copy.dist;
4798 if ((uInt)(q - s->window) < c->sub.copy.dist)
4799 f = s->end - (c->sub.copy.dist - (uInt)(q - s->window));
4800#endif
4801 while (c->len)
4802 {
4803 NEEDOUT
4804 OUTBYTE(*f++)
4805 if (f == s->end)
4806 f = s->window;
4807 c->len--;
4808 }
4809 c->mode = START;
4810 break;
4811 case LIT: /* o: got literal, waiting for output space */
4812 NEEDOUT
4813 OUTBYTE(c->sub.lit)
4814 c->mode = START;
4815 break;
4816 case WASH: /* o: got eob, possibly more output */
4817 FLUSH
4818 if (s->read != s->write)
4819 LEAVE
4820 c->mode = END;
4821 case END:
4822 r = Z_STREAM_END;
4823 LEAVE
4824 case BADCODE: /* x: got error */
4825 r = Z_DATA_ERROR;
4826 LEAVE
4827 default:
4828 r = Z_STREAM_ERROR;
4829 LEAVE
4830 }
4831}
4832
4833
4834void inflate_codes_free(c, z)
4835inflate_codes_statef *c;
4836z_streamp z;
4837{
4838 ZFREE(z, c);
4839 Tracev((stderr, "inflate: codes free\n"));
4840}
4841/* --- infcodes.c */
4842
4843/* +++ infutil.c */
4844/* inflate_util.c -- data and routines common to blocks and codes
4845 * Copyright (C) 1995-1996 Mark Adler
4846 * For conditions of distribution and use, see copyright notice in zlib.h
4847 */
4848
4849/* #include "zutil.h" */
4850/* #include "infblock.h" */
4851/* #include "inftrees.h" */
4852/* #include "infcodes.h" */
4853/* #include "infutil.h" */
4854
4855#ifndef NO_DUMMY_DECL
4856struct inflate_codes_state {int dummy;}; /* for buggy compilers */
4857#endif
4858
4859/* And'ing with mask[n] masks the lower n bits */
4860uInt inflate_mask[17] = {
4861 0x0000,
4862 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
4863 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
4864};
4865
4866
4867/* copy as much as possible from the sliding window to the output area */
4868int inflate_flush(s, z, r)
4869inflate_blocks_statef *s;
4870z_streamp z;
4871int r;
4872{
4873 uInt n;
4874 Bytef *p;
4875 Bytef *q;
4876
4877 /* local copies of source and destination pointers */
4878 p = z->next_out;
4879 q = s->read;
4880
4881 /* compute number of bytes to copy as far as end of window */
4882 n = (uInt)((q <= s->write ? s->write : s->end) - q);
4883 if (n > z->avail_out) n = z->avail_out;
4884 if (n && r == Z_BUF_ERROR) r = Z_OK;
4885
4886 /* update counters */
4887 z->avail_out -= n;
4888 z->total_out += n;
4889
4890 /* update check information */
4891 if (s->checkfn != Z_NULL)
4892 z->adler = s->check = (*s->checkfn)(s->check, q, n);
4893
4894 /* copy as far as end of window */
4895 if (p != Z_NULL) {
4896 zmemcpy(p, q, n);
4897 p += n;
4898 }
4899 q += n;
4900
4901 /* see if more to copy at beginning of window */
4902 if (q == s->end)
4903 {
4904 /* wrap pointers */
4905 q = s->window;
4906 if (s->write == s->end)
4907 s->write = s->window;
4908
4909 /* compute bytes to copy */
4910 n = (uInt)(s->write - q);
4911 if (n > z->avail_out) n = z->avail_out;
4912 if (n && r == Z_BUF_ERROR) r = Z_OK;
4913
4914 /* update counters */
4915 z->avail_out -= n;
4916 z->total_out += n;
4917
4918 /* update check information */
4919 if (s->checkfn != Z_NULL)
4920 z->adler = s->check = (*s->checkfn)(s->check, q, n);
4921
4922 /* copy */
4923 if (p != Z_NULL) {
4924 zmemcpy(p, q, n);
4925 p += n;
4926 }
4927 q += n;
4928 }
4929
4930 /* update pointers */
4931 z->next_out = p;
4932 s->read = q;
4933
4934 /* done */
4935 return r;
4936}
4937/* --- infutil.c */
4938
4939/* +++ inffast.c */
4940/* inffast.c -- process literals and length/distance pairs fast
4941 * Copyright (C) 1995-1996 Mark Adler
4942 * For conditions of distribution and use, see copyright notice in zlib.h
4943 */
4944
4945/* #include "zutil.h" */
4946/* #include "inftrees.h" */
4947/* #include "infblock.h" */
4948/* #include "infcodes.h" */
4949/* #include "infutil.h" */
4950/* #include "inffast.h" */
4951
4952#ifndef NO_DUMMY_DECL
4953struct inflate_codes_state {int dummy;}; /* for buggy compilers */
4954#endif
4955
4956/* simplify the use of the inflate_huft type with some defines */
4957#define base more.Base
4958#define next more.Next
4959#define exop word.what.Exop
4960#define bits word.what.Bits
4961
4962/* macros for bit input with no checking and for returning unused bytes */
4963#define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}}
4964#define UNGRAB {n+=(c=k>>3);p-=c;k&=7;}
4965
4966/* Called with number of bytes left to write in window at least 258
4967 (the maximum string length) and number of input bytes available
4968 at least ten. The ten bytes are six bytes for the longest length/
4969 distance pair plus four bytes for overloading the bit buffer. */
4970
4971int inflate_fast(bl, bd, tl, td, s, z)
4972uInt bl, bd;
4973inflate_huft *tl;
4974inflate_huft *td; /* need separate declaration for Borland C++ */
4975inflate_blocks_statef *s;
4976z_streamp z;
4977{
4978 inflate_huft *t; /* temporary pointer */
4979 uInt e; /* extra bits or operation */
4980 uLong b; /* bit buffer */
4981 uInt k; /* bits in bit buffer */
4982 Bytef *p; /* input data pointer */
4983 uInt n; /* bytes available there */
4984 Bytef *q; /* output window write pointer */
4985 uInt m; /* bytes to end of window or read pointer */
4986 uInt ml; /* mask for literal/length tree */
4987 uInt md; /* mask for distance tree */
4988 uInt c; /* bytes to copy */
4989 uInt d; /* distance back to copy from */
4990 Bytef *r; /* copy source pointer */
4991
4992 /* load input, output, bit values */
4993 LOAD
4994
4995 /* initialize masks */
4996 ml = inflate_mask[bl];
4997 md = inflate_mask[bd];
4998
4999 /* do until not enough input or output space for fast loop */
5000 do { /* assume called with m >= 258 && n >= 10 */
5001 /* get literal/length code */
5002 GRABBITS(20) /* max bits for literal/length code */
5003 if ((e = (t = tl + ((uInt)b & ml))->exop) == 0)
5004 {
5005 DUMPBITS(t->bits)
5006 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5007 "inflate: * literal '%c'\n" :
5008 "inflate: * literal 0x%02x\n", t->base));
5009 *q++ = (Byte)t->base;
5010 m--;
5011 continue;
5012 }
5013 do {
5014 DUMPBITS(t->bits)
5015 if (e & 16)
5016 {
5017 /* get extra bits for length */
5018 e &= 15;
5019 c = t->base + ((uInt)b & inflate_mask[e]);
5020 DUMPBITS(e)
5021 Tracevv((stderr, "inflate: * length %u\n", c));
5022
5023 /* decode distance base of block to copy */
5024 GRABBITS(15); /* max bits for distance code */
5025 e = (t = td + ((uInt)b & md))->exop;
5026 do {
5027 DUMPBITS(t->bits)
5028 if (e & 16)
5029 {
5030 /* get extra bits to add to distance base */
5031 e &= 15;
5032 GRABBITS(e) /* get extra bits (up to 13) */
5033 d = t->base + ((uInt)b & inflate_mask[e]);
5034 DUMPBITS(e)
5035 Tracevv((stderr, "inflate: * distance %u\n", d));
5036
5037 /* do the copy */
5038 m -= c;
5039 if ((uInt)(q - s->window) >= d) /* offset before dest */
5040 { /* just copy */
5041 r = q - d;
5042 *q++ = *r++; c--; /* minimum count is three, */
5043 *q++ = *r++; c--; /* so unroll loop a little */
5044 }
5045 else /* else offset after destination */
5046 {
5047 e = d - (uInt)(q - s->window); /* bytes from offset to end */
5048 r = s->end - e; /* pointer to offset */
5049 if (c > e) /* if source crosses, */
5050 {
5051 c -= e; /* copy to end of window */
5052 do {
5053 *q++ = *r++;
5054 } while (--e);
5055 r = s->window; /* copy rest from start of window */
5056 }
5057 }
5058 do { /* copy all or what's left */
5059 *q++ = *r++;
5060 } while (--c);
5061 break;
5062 }
5063 else if ((e & 64) == 0)
5064 e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop;
5065 else
5066 {
5067 z->msg = (char*)"invalid distance code";
5068 UNGRAB
5069 UPDATE
5070 return Z_DATA_ERROR;
5071 }
5072 } while (1);
5073 break;
5074 }
5075 if ((e & 64) == 0)
5076 {
5077 if ((e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop) == 0)
5078 {
5079 DUMPBITS(t->bits)
5080 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5081 "inflate: * literal '%c'\n" :
5082 "inflate: * literal 0x%02x\n", t->base));
5083 *q++ = (Byte)t->base;
5084 m--;
5085 break;
5086 }
5087 }
5088 else if (e & 32)
5089 {
5090 Tracevv((stderr, "inflate: * end of block\n"));
5091 UNGRAB
5092 UPDATE
5093 return Z_STREAM_END;
5094 }
5095 else
5096 {
5097 z->msg = (char*)"invalid literal/length code";
5098 UNGRAB
5099 UPDATE
5100 return Z_DATA_ERROR;
5101 }
5102 } while (1);
5103 } while (m >= 258 && n >= 10);
5104
5105 /* not enough input or output--restore pointers and return */
5106 UNGRAB
5107 UPDATE
5108 return Z_OK;
5109}
5110/* --- inffast.c */
5111
5112/* +++ zutil.c */
5113/* zutil.c -- target dependent utility functions for the compression library
5114 * Copyright (C) 1995-1996 Jean-loup Gailly.
5115 * For conditions of distribution and use, see copyright notice in zlib.h
5116 */
5117
5118/* From: zutil.c,v 1.17 1996/07/24 13:41:12 me Exp $ */
5119
5120#ifdef DEBUG_ZLIB
5121#include <stdio.h>
5122#endif
5123
5124/* #include "zutil.h" */
5125
5126#ifndef NO_DUMMY_DECL
5127struct internal_state {int dummy;}; /* for buggy compilers */
5128#endif
5129
5130#ifndef STDC
5131extern void exit OF((int));
5132#endif
5133
5134static const char *z_errmsg[10] = {
5135"need dictionary", /* Z_NEED_DICT 2 */
5136"stream end", /* Z_STREAM_END 1 */
5137"", /* Z_OK 0 */
5138"file error", /* Z_ERRNO (-1) */
5139"stream error", /* Z_STREAM_ERROR (-2) */
5140"data error", /* Z_DATA_ERROR (-3) */
5141"insufficient memory", /* Z_MEM_ERROR (-4) */
5142"buffer error", /* Z_BUF_ERROR (-5) */
5143"incompatible version",/* Z_VERSION_ERROR (-6) */
5144""};
5145
5146
5147const char *zlibVersion()
5148{
5149 return ZLIB_VERSION;
5150}
5151
5152#ifdef DEBUG_ZLIB
5153void z_error (m)
5154 char *m;
5155{
5156 fprintf(stderr, "%s\n", m);
5157 exit(1);
5158}
5159#endif
5160
5161#ifndef HAVE_MEMCPY
5162
5163void zmemcpy(dest, source, len)
5164 Bytef* dest;
5165 Bytef* source;
5166 uInt len;
5167{
5168 if (len == 0) return;
5169 do {
5170 *dest++ = *source++; /* ??? to be unrolled */
5171 } while (--len != 0);
5172}
5173
5174int zmemcmp(s1, s2, len)
5175 Bytef* s1;
5176 Bytef* s2;
5177 uInt len;
5178{
5179 uInt j;
5180
5181 for (j = 0; j < len; j++) {
5182 if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1;
5183 }
5184 return 0;
5185}
5186
5187void zmemzero(dest, len)
5188 Bytef* dest;
5189 uInt len;
5190{
5191 if (len == 0) return;
5192 do {
5193 *dest++ = 0; /* ??? to be unrolled */
5194 } while (--len != 0);
5195}
5196#endif
5197
5198#ifdef __TURBOC__
5199#if (defined( __BORLANDC__) || !defined(SMALL_MEDIUM)) && !defined(__32BIT__)
5200/* Small and medium model in Turbo C are for now limited to near allocation
5201 * with reduced MAX_WBITS and MAX_MEM_LEVEL
5202 */
5203# define MY_ZCALLOC
5204
5205/* Turbo C malloc() does not allow dynamic allocation of 64K bytes
5206 * and farmalloc(64K) returns a pointer with an offset of 8, so we
5207 * must fix the pointer. Warning: the pointer must be put back to its
5208 * original form in order to free it, use zcfree().
5209 */
5210
5211#define MAX_PTR 10
5212/* 10*64K = 640K */
5213
5214local int next_ptr = 0;
5215
5216typedef struct ptr_table_s {
5217 voidpf org_ptr;
5218 voidpf new_ptr;
5219} ptr_table;
5220
5221local ptr_table table[MAX_PTR];
5222/* This table is used to remember the original form of pointers
5223 * to large buffers (64K). Such pointers are normalized with a zero offset.
5224 * Since MSDOS is not a preemptive multitasking OS, this table is not
5225 * protected from concurrent access. This hack doesn't work anyway on
5226 * a protected system like OS/2. Use Microsoft C instead.
5227 */
5228
5229voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
5230{
5231 voidpf buf = opaque; /* just to make some compilers happy */
5232 ulg bsize = (ulg)items*size;
5233
5234 /* If we allocate less than 65520 bytes, we assume that farmalloc
5235 * will return a usable pointer which doesn't have to be normalized.
5236 */
5237 if (bsize < 65520L) {
5238 buf = farmalloc(bsize);
5239 if (*(ush*)&buf != 0) return buf;
5240 } else {
5241 buf = farmalloc(bsize + 16L);
5242 }
5243 if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
5244 table[next_ptr].org_ptr = buf;
5245
5246 /* Normalize the pointer to seg:0 */
5247 *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
5248 *(ush*)&buf = 0;
5249 table[next_ptr++].new_ptr = buf;
5250 return buf;
5251}
5252
5253void zcfree (voidpf opaque, voidpf ptr)
5254{
5255 int n;
5256 if (*(ush*)&ptr != 0) { /* object < 64K */
5257 farfree(ptr);
5258 return;
5259 }
5260 /* Find the original pointer */
5261 for (n = 0; n < next_ptr; n++) {
5262 if (ptr != table[n].new_ptr) continue;
5263
5264 farfree(table[n].org_ptr);
5265 while (++n < next_ptr) {
5266 table[n-1] = table[n];
5267 }
5268 next_ptr--;
5269 return;
5270 }
5271 ptr = opaque; /* just to make some compilers happy */
5272 Assert(0, "zcfree: ptr not found");
5273}
5274#endif
5275#endif /* __TURBOC__ */
5276
5277
5278#if defined(M_I86) && !defined(__32BIT__)
5279/* Microsoft C in 16-bit mode */
5280
5281# define MY_ZCALLOC
5282
5283#if (!defined(_MSC_VER) || (_MSC_VER < 600))
5284# define _halloc halloc
5285# define _hfree hfree
5286#endif
5287
5288voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
5289{
5290 if (opaque) opaque = 0; /* to make compiler happy */
5291 return _halloc((long)items, size);
5292}
5293
5294void zcfree (voidpf opaque, voidpf ptr)
5295{
5296 if (opaque) opaque = 0; /* to make compiler happy */
5297 _hfree(ptr);
5298}
5299
5300#endif /* MSC */
5301
5302
5303#ifndef MY_ZCALLOC /* Any system without a special alloc function */
5304
5305#ifndef STDC
5306extern voidp calloc OF((uInt items, uInt size));
5307extern void free OF((voidpf ptr));
5308#endif
5309
5310voidpf zcalloc (opaque, items, size)
5311 voidpf opaque;
5312 unsigned items;
5313 unsigned size;
5314{
5315 if (opaque) items += size - size; /* make compiler happy */
5316 return (voidpf)calloc(items, size);
5317}
5318
5319void zcfree (opaque, ptr)
5320 voidpf opaque;
5321 voidpf ptr;
5322{
5323 free(ptr);
5324 if (opaque) return; /* make compiler happy */
5325}
5326
5327#endif /* MY_ZCALLOC */
5328/* --- zutil.c */
5329
5330/* +++ adler32.c */
5331/* adler32.c -- compute the Adler-32 checksum of a data stream
5332 * Copyright (C) 1995-1996 Mark Adler
5333 * For conditions of distribution and use, see copyright notice in zlib.h
5334 */
5335
5336/* From: adler32.c,v 1.10 1996/05/22 11:52:18 me Exp $ */
5337
5338/* #include "zlib.h" */
5339
5340#define BASE 65521L /* largest prime smaller than 65536 */
5341#define NMAX 5552
5342/* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
5343
5344#define DO1(buf,i) {s1 += buf[i]; s2 += s1;}
5345#define DO2(buf,i) DO1(buf,i); DO1(buf,i+1);
5346#define DO4(buf,i) DO2(buf,i); DO2(buf,i+2);
5347#define DO8(buf,i) DO4(buf,i); DO4(buf,i+4);
5348#define DO16(buf) DO8(buf,0); DO8(buf,8);
5349
5350/* ========================================================================= */
5351uLong adler32(adler, buf, len)
5352 uLong adler;
5353 const Bytef *buf;
5354 uInt len;
5355{
5356 unsigned long s1 = adler & 0xffff;
5357 unsigned long s2 = (adler >> 16) & 0xffff;
5358 int k;
5359
5360 if (buf == Z_NULL) return 1L;
5361
5362 while (len > 0) {
5363 k = len < NMAX ? len : NMAX;
5364 len -= k;
5365 while (k >= 16) {
5366 DO16(buf);
5367 buf += 16;
5368 k -= 16;
5369 }
5370 if (k != 0) do {
5371 s1 += *buf++;
5372 s2 += s1;
5373 } while (--k);
5374 s1 %= BASE;
5375 s2 %= BASE;
5376 }
5377 return (s2 << 16) | s1;
5378}
5379/* --- adler32.c */