zlib.c revision 272461
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 * $FreeBSD: releng/10.1/sys/net/zlib.c 245102 2013-01-06 14:59:59Z peter $ 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) 28#define _tr_init _zlib104_tr_init 29#define _tr_align _zlib104_tr_align 30#define _tr_tally _zlib104_tr_tally 31#define _tr_flush_block _zlib104_tr_flush_block 32#define _tr_stored_block _zlib104_tr_stored_block 33#define inflate_fast _zlib104_inflate_fast 34#define inflate _zlib104_inflate 35#define zlibVersion _zlib104_Version 36#endif 37 38 39/* +++ zutil.h */ 40/*- 41 * zutil.h -- internal interface and configuration of the compression library 42 * Copyright (C) 1995-1996 Jean-loup Gailly. 43 * For conditions of distribution and use, see copyright notice in zlib.h 44 */ 45 46/* WARNING: this file should *not* be used by applications. It is 47 part of the implementation of the compression library and is 48 subject to change. Applications should only use zlib.h. 49 */ 50 51/* From: zutil.h,v 1.16 1996/07/24 13:41:13 me Exp $ */ 52 53#ifndef _Z_UTIL_H 54#define _Z_UTIL_H 55 56#ifdef _KERNEL 57#include <net/zlib.h> 58#else 59#include "zlib.h" 60#endif 61 62#ifdef _KERNEL 63/* Assume this is a *BSD or SVR4 kernel */ 64#include <sys/types.h> 65#include <sys/time.h> 66#include <sys/systm.h> 67#include <sys/param.h> 68#include <sys/kernel.h> 69#include <sys/module.h> 70# define HAVE_MEMCPY 71 72#else 73#if defined(__KERNEL__) 74/* Assume this is a Linux kernel */ 75#include <linux/string.h> 76#define HAVE_MEMCPY 77 78#else /* not kernel */ 79 80#if defined(MSDOS)||defined(VMS)||defined(CRAY)||defined(WIN32)||defined(RISCOS) 81# include <stddef.h> 82# include <errno.h> 83#else 84 extern int errno; 85#endif 86#ifdef STDC 87# include <string.h> 88# include <stdlib.h> 89#endif 90#endif /* __KERNEL__ */ 91#endif /* _KERNEL */ 92 93#ifndef local 94# define local static 95#endif 96/* compile with -Dlocal if your debugger can't find static symbols */ 97 98typedef unsigned char uch; 99typedef uch FAR uchf; 100typedef unsigned short ush; 101typedef ush FAR ushf; 102typedef unsigned long ulg; 103 104static const char *z_errmsg[10]; /* indexed by 2-zlib_error */ 105/* (size given to avoid silly warnings with Visual C++) */ 106 107#define ERR_MSG(err) z_errmsg[Z_NEED_DICT-(err)] 108 109#define ERR_RETURN(strm,err) \ 110 return (strm->msg = (const char*)ERR_MSG(err), (err)) 111/* To be used only when the state is known to be valid */ 112 113 /* common constants */ 114 115#ifndef DEF_WBITS 116# define DEF_WBITS MAX_WBITS 117#endif 118/* default windowBits for decompression. MAX_WBITS is for compression only */ 119 120#if MAX_MEM_LEVEL >= 8 121# define DEF_MEM_LEVEL 8 122#else 123# define DEF_MEM_LEVEL MAX_MEM_LEVEL 124#endif 125/* default memLevel */ 126 127#define STORED_BLOCK 0 128#define STATIC_TREES 1 129#define DYN_TREES 2 130/* The three kinds of block type */ 131 132#define MIN_MATCH 3 133#define MAX_MATCH 258 134/* The minimum and maximum match lengths */ 135 136#define PRESET_DICT 0x20 /* preset dictionary flag in zlib header */ 137 138 /* target dependencies */ 139 140#ifdef MSDOS 141# define OS_CODE 0x00 142# ifdef __TURBOC__ 143# include <alloc.h> 144# else /* MSC or DJGPP */ 145# include <malloc.h> 146# endif 147#endif 148 149#ifdef OS2 150# define OS_CODE 0x06 151#endif 152 153#ifdef WIN32 /* Window 95 & Windows NT */ 154# define OS_CODE 0x0b 155#endif 156 157#if defined(VAXC) || defined(VMS) 158# define OS_CODE 0x02 159# define FOPEN(name, mode) \ 160 fopen((name), (mode), "mbc=60", "ctx=stm", "rfm=fix", "mrs=512") 161#endif 162 163#ifdef AMIGA 164# define OS_CODE 0x01 165#endif 166 167#if defined(ATARI) || defined(atarist) 168# define OS_CODE 0x05 169#endif 170 171#ifdef MACOS 172# define OS_CODE 0x07 173#endif 174 175#ifdef __50SERIES /* Prime/PRIMOS */ 176# define OS_CODE 0x0F 177#endif 178 179#ifdef TOPS20 180# define OS_CODE 0x0a 181#endif 182 183#if defined(_BEOS_) || defined(RISCOS) 184# define fdopen(fd,mode) NULL /* No fdopen() */ 185#endif 186 187 /* Common defaults */ 188 189#ifndef OS_CODE 190# define OS_CODE 0x03 /* assume Unix */ 191#endif 192 193#ifndef FOPEN 194# define FOPEN(name, mode) fopen((name), (mode)) 195#endif 196 197 /* functions */ 198 199#ifdef HAVE_STRERROR 200 extern char *strerror OF((int)); 201# define zstrerror(errnum) strerror(errnum) 202#else 203# define zstrerror(errnum) "" 204#endif 205 206#if defined(pyr) 207# define NO_MEMCPY 208#endif 209#if (defined(M_I86SM) || defined(M_I86MM)) && !defined(_MSC_VER) 210 /* Use our own functions for small and medium model with MSC <= 5.0. 211 * You may have to use the same strategy for Borland C (untested). 212 */ 213# define NO_MEMCPY 214#endif 215#if defined(STDC) && !defined(HAVE_MEMCPY) && !defined(NO_MEMCPY) 216# define HAVE_MEMCPY 217#endif 218#ifdef HAVE_MEMCPY 219# ifdef SMALL_MEDIUM /* MSDOS small or medium model */ 220# define zmemcpy _fmemcpy 221# define zmemcmp _fmemcmp 222# define zmemzero(dest, len) _fmemset(dest, 0, len) 223# else 224# define zmemcpy memcpy 225# define zmemcmp memcmp 226# define zmemzero(dest, len) memset(dest, 0, len) 227# endif 228#else 229 extern void zmemcpy OF((Bytef* dest, Bytef* source, uInt len)); 230 extern int zmemcmp OF((Bytef* s1, Bytef* s2, uInt len)); 231 extern void zmemzero OF((Bytef* dest, uInt len)); 232#endif 233 234/* Diagnostic functions */ 235#ifdef DEBUG_ZLIB 236# include <stdio.h> 237# ifndef verbose 238# define verbose 0 239# endif 240 extern void z_error OF((char *m)); 241# define Assert(cond,msg) {if(!(cond)) z_error(msg);} 242# define Trace(x) fprintf x 243# define Tracev(x) {if (verbose) fprintf x ;} 244# define Tracevv(x) {if (verbose>1) fprintf x ;} 245# define Tracec(c,x) {if (verbose && (c)) fprintf x ;} 246# define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;} 247#else 248# define Assert(cond,msg) 249# define Trace(x) 250# define Tracev(x) 251# define Tracevv(x) 252# define Tracec(c,x) 253# define Tracecv(c,x) 254#endif 255 256 257typedef uLong (*check_func) OF((uLong check, const Bytef *buf, uInt len)); 258 259voidpf zcalloc OF((voidpf opaque, unsigned items, unsigned size)); 260void zcfree OF((voidpf opaque, voidpf ptr)); 261 262#define ZALLOC(strm, items, size) \ 263 (*((strm)->zalloc))((strm)->opaque, (items), (size)) 264#define ZFREE(strm, addr) (*((strm)->zfree))((strm)->opaque, (voidpf)(addr)) 265#define TRY_FREE(s, p) {if (p) ZFREE(s, p);} 266 267#endif /* _Z_UTIL_H */ 268/* --- zutil.h */ 269 270/* +++ deflate.h */ 271/* deflate.h -- internal compression state 272 * Copyright (C) 1995-1996 Jean-loup Gailly 273 * For conditions of distribution and use, see copyright notice in zlib.h 274 */ 275 276/* WARNING: this file should *not* be used by applications. It is 277 part of the implementation of the compression library and is 278 subject to change. Applications should only use zlib.h. 279 */ 280 281/* From: deflate.h,v 1.10 1996/07/02 12:41:00 me Exp $ */ 282 283#ifndef _DEFLATE_H 284#define _DEFLATE_H 285 286/* #include "zutil.h" */ 287 288/* =========================================================================== 289 * Internal compression state. 290 */ 291 292#define LENGTH_CODES 29 293/* number of length codes, not counting the special END_BLOCK code */ 294 295#define LITERALS 256 296/* number of literal bytes 0..255 */ 297 298#define L_CODES (LITERALS+1+LENGTH_CODES) 299/* number of Literal or Length codes, including the END_BLOCK code */ 300 301#define D_CODES 30 302/* number of distance codes */ 303 304#define BL_CODES 19 305/* number of codes used to transfer the bit lengths */ 306 307#define HEAP_SIZE (2*L_CODES+1) 308/* maximum heap size */ 309 310#define MAX_BITS 15 311/* All codes must not exceed MAX_BITS bits */ 312 313#define INIT_STATE 42 314#define BUSY_STATE 113 315#define FINISH_STATE 666 316/* Stream status */ 317 318 319/* Data structure describing a single value and its code string. */ 320typedef struct ct_data_s { 321 union { 322 ush freq; /* frequency count */ 323 ush code; /* bit string */ 324 } fc; 325 union { 326 ush dad; /* father node in Huffman tree */ 327 ush len; /* length of bit string */ 328 } dl; 329} FAR ct_data; 330 331#define Freq fc.freq 332#define Code fc.code 333#define Dad dl.dad 334#define Len dl.len 335 336typedef struct static_tree_desc_s static_tree_desc; 337 338typedef struct tree_desc_s { 339 ct_data *dyn_tree; /* the dynamic tree */ 340 int max_code; /* largest code with non zero frequency */ 341 static_tree_desc *stat_desc; /* the corresponding static tree */ 342} FAR tree_desc; 343 344typedef ush Pos; 345typedef Pos FAR Posf; 346typedef unsigned IPos; 347 348/* A Pos is an index in the character window. We use short instead of int to 349 * save space in the various tables. IPos is used only for parameter passing. 350 */ 351 352typedef struct deflate_state { 353 z_streamp strm; /* pointer back to this zlib stream */ 354 int status; /* as the name implies */ 355 Bytef *pending_buf; /* output still pending */ 356 ulg pending_buf_size; /* size of pending_buf */ 357 Bytef *pending_out; /* next pending byte to output to the stream */ 358 int pending; /* nb of bytes in the pending buffer */ 359 int noheader; /* suppress zlib header and adler32 */ 360 Byte data_type; /* UNKNOWN, BINARY or ASCII */ 361 Byte method; /* STORED (for zip only) or DEFLATED */ 362 int last_flush; /* value of flush param for previous deflate call */ 363 364 /* used by deflate.c: */ 365 366 uInt w_size; /* LZ77 window size (32K by default) */ 367 uInt w_bits; /* log2(w_size) (8..16) */ 368 uInt w_mask; /* w_size - 1 */ 369 370 Bytef *window; 371 /* Sliding window. Input bytes are read into the second half of the window, 372 * and move to the first half later to keep a dictionary of at least wSize 373 * bytes. With this organization, matches are limited to a distance of 374 * wSize-MAX_MATCH bytes, but this ensures that IO is always 375 * performed with a length multiple of the block size. Also, it limits 376 * the window size to 64K, which is quite useful on MSDOS. 377 * To do: use the user input buffer as sliding window. 378 */ 379 380 ulg window_size; 381 /* Actual size of window: 2*wSize, except when the user input buffer 382 * is directly used as sliding window. 383 */ 384 385 Posf *prev; 386 /* Link to older string with same hash index. To limit the size of this 387 * array to 64K, this link is maintained only for the last 32K strings. 388 * An index in this array is thus a window index modulo 32K. 389 */ 390 391 Posf *head; /* Heads of the hash chains or NIL. */ 392 393 uInt ins_h; /* hash index of string to be inserted */ 394 uInt hash_size; /* number of elements in hash table */ 395 uInt hash_bits; /* log2(hash_size) */ 396 uInt hash_mask; /* hash_size-1 */ 397 398 uInt hash_shift; 399 /* Number of bits by which ins_h must be shifted at each input 400 * step. It must be such that after MIN_MATCH steps, the oldest 401 * byte no longer takes part in the hash key, that is: 402 * hash_shift * MIN_MATCH >= hash_bits 403 */ 404 405 long block_start; 406 /* Window position at the beginning of the current output block. Gets 407 * negative when the window is moved backwards. 408 */ 409 410 uInt match_length; /* length of best match */ 411 IPos prev_match; /* previous match */ 412 int match_available; /* set if previous match exists */ 413 uInt strstart; /* start of string to insert */ 414 uInt match_start; /* start of matching string */ 415 uInt lookahead; /* number of valid bytes ahead in window */ 416 417 uInt prev_length; 418 /* Length of the best match at previous step. Matches not greater than this 419 * are discarded. This is used in the lazy match evaluation. 420 */ 421 422 uInt max_chain_length; 423 /* To speed up deflation, hash chains are never searched beyond this 424 * length. A higher limit improves compression ratio but degrades the 425 * speed. 426 */ 427 428 uInt max_lazy_match; 429 /* Attempt to find a better match only when the current match is strictly 430 * smaller than this value. This mechanism is used only for compression 431 * levels >= 4. 432 */ 433# define max_insert_length max_lazy_match 434 /* Insert new strings in the hash table only if the match length is not 435 * greater than this length. This saves time but degrades compression. 436 * max_insert_length is used only for compression levels <= 3. 437 */ 438 439 int level; /* compression level (1..9) */ 440 int strategy; /* favor or force Huffman coding*/ 441 442 uInt good_match; 443 /* Use a faster search when the previous match is longer than this */ 444 445 int nice_match; /* Stop searching when current match exceeds this */ 446 447 /* used by trees.c: */ 448 /* Didn't use ct_data typedef below to supress compiler warning */ 449 struct ct_data_s dyn_ltree[HEAP_SIZE]; /* literal and length tree */ 450 struct ct_data_s dyn_dtree[2*D_CODES+1]; /* distance tree */ 451 struct ct_data_s bl_tree[2*BL_CODES+1]; /* Huffman tree for bit lengths */ 452 453 struct tree_desc_s l_desc; /* desc. for literal tree */ 454 struct tree_desc_s d_desc; /* desc. for distance tree */ 455 struct tree_desc_s bl_desc; /* desc. for bit length tree */ 456 457 ush bl_count[MAX_BITS+1]; 458 /* number of codes at each bit length for an optimal tree */ 459 460 int heap[2*L_CODES+1]; /* heap used to build the Huffman trees */ 461 int heap_len; /* number of elements in the heap */ 462 int heap_max; /* element of largest frequency */ 463 /* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used. 464 * The same heap array is used to build all trees. 465 */ 466 467 uch depth[2*L_CODES+1]; 468 /* Depth of each subtree used as tie breaker for trees of equal frequency 469 */ 470 471 uchf *l_buf; /* buffer for literals or lengths */ 472 473 uInt lit_bufsize; 474 /* Size of match buffer for literals/lengths. There are 4 reasons for 475 * limiting lit_bufsize to 64K: 476 * - frequencies can be kept in 16 bit counters 477 * - if compression is not successful for the first block, all input 478 * data is still in the window so we can still emit a stored block even 479 * when input comes from standard input. (This can also be done for 480 * all blocks if lit_bufsize is not greater than 32K.) 481 * - if compression is not successful for a file smaller than 64K, we can 482 * even emit a stored file instead of a stored block (saving 5 bytes). 483 * This is applicable only for zip (not gzip or zlib). 484 * - creating new Huffman trees less frequently may not provide fast 485 * adaptation to changes in the input data statistics. (Take for 486 * example a binary file with poorly compressible code followed by 487 * a highly compressible string table.) Smaller buffer sizes give 488 * fast adaptation but have of course the overhead of transmitting 489 * trees more frequently. 490 * - I can't count above 4 491 */ 492 493 uInt last_lit; /* running index in l_buf */ 494 495 ushf *d_buf; 496 /* Buffer for distances. To simplify the code, d_buf and l_buf have 497 * the same number of elements. To use different lengths, an extra flag 498 * array would be necessary. 499 */ 500 501 ulg opt_len; /* bit length of current block with optimal trees */ 502 ulg static_len; /* bit length of current block with static trees */ 503 ulg compressed_len; /* total bit length of compressed file */ 504 uInt matches; /* number of string matches in current block */ 505 int last_eob_len; /* bit length of EOB code for last block */ 506 507#ifdef DEBUG_ZLIB 508 ulg bits_sent; /* bit length of the compressed data */ 509#endif 510 511 ush bi_buf; 512 /* Output buffer. bits are inserted starting at the bottom (least 513 * significant bits). 514 */ 515 int bi_valid; 516 /* Number of valid bits in bi_buf. All bits above the last valid bit 517 * are always zero. 518 */ 519 520} FAR deflate_state; 521 522/* Output a byte on the stream. 523 * IN assertion: there is enough room in pending_buf. 524 */ 525#define put_byte(s, c) {s->pending_buf[s->pending++] = (c);} 526 527 528#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1) 529/* Minimum amount of lookahead, except at the end of the input file. 530 * See deflate.c for comments about the MIN_MATCH+1. 531 */ 532 533#define MAX_DIST(s) ((s)->w_size-MIN_LOOKAHEAD) 534/* In order to simplify the code, particularly on 16 bit machines, match 535 * distances are limited to MAX_DIST instead of WSIZE. 536 */ 537 538 /* in trees.c */ 539void _tr_init OF((deflate_state *s)); 540int _tr_tally OF((deflate_state *s, unsigned dist, unsigned lc)); 541ulg _tr_flush_block OF((deflate_state *s, charf *buf, ulg stored_len, 542 int eof)); 543void _tr_align OF((deflate_state *s)); 544void _tr_stored_block OF((deflate_state *s, charf *buf, ulg stored_len, 545 int eof)); 546void _tr_stored_type_only OF((deflate_state *)); 547 548#endif 549/* --- deflate.h */ 550 551/* +++ deflate.c */ 552/* deflate.c -- compress data using the deflation algorithm 553 * Copyright (C) 1995-1996 Jean-loup Gailly. 554 * For conditions of distribution and use, see copyright notice in zlib.h 555 */ 556 557/* 558 * ALGORITHM 559 * 560 * The "deflation" process depends on being able to identify portions 561 * of the input text which are identical to earlier input (within a 562 * sliding window trailing behind the input currently being processed). 563 * 564 * The most straightforward technique turns out to be the fastest for 565 * most input files: try all possible matches and select the longest. 566 * The key feature of this algorithm is that insertions into the string 567 * dictionary are very simple and thus fast, and deletions are avoided 568 * completely. Insertions are performed at each input character, whereas 569 * string matches are performed only when the previous match ends. So it 570 * is preferable to spend more time in matches to allow very fast string 571 * insertions and avoid deletions. The matching algorithm for small 572 * strings is inspired from that of Rabin & Karp. A brute force approach 573 * is used to find longer strings when a small match has been found. 574 * A similar algorithm is used in comic (by Jan-Mark Wams) and freeze 575 * (by Leonid Broukhis). 576 * A previous version of this file used a more sophisticated algorithm 577 * (by Fiala and Greene) which is guaranteed to run in linear amortized 578 * time, but has a larger average cost, uses more memory and is patented. 579 * However the F&G algorithm may be faster for some highly redundant 580 * files if the parameter max_chain_length (described below) is too large. 581 * 582 * ACKNOWLEDGEMENTS 583 * 584 * The idea of lazy evaluation of matches is due to Jan-Mark Wams, and 585 * I found it in 'freeze' written by Leonid Broukhis. 586 * Thanks to many people for bug reports and testing. 587 * 588 * REFERENCES 589 * 590 * Deutsch, L.P.,"DEFLATE Compressed Data Format Specification". 591 * Available in ftp://ds.internic.net/rfc/rfc1951.txt 592 * 593 * A description of the Rabin and Karp algorithm is given in the book 594 * "Algorithms" by R. Sedgewick, Addison-Wesley, p252. 595 * 596 * Fiala,E.R., and Greene,D.H. 597 * Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595 598 * 599 */ 600 601/* From: deflate.c,v 1.15 1996/07/24 13:40:58 me Exp $ */ 602 603/* #include "deflate.h" */ 604 605char deflate_copyright[] = " deflate 1.0.4 Copyright 1995-1996 Jean-loup Gailly "; 606/* 607 If you use the zlib library in a product, an acknowledgment is welcome 608 in the documentation of your product. If for some reason you cannot 609 include such an acknowledgment, I would appreciate that you keep this 610 copyright string in the executable of your product. 611 */ 612 613/* =========================================================================== 614 * Function prototypes. 615 */ 616typedef enum { 617 need_more, /* block not completed, need more input or more output */ 618 block_done, /* block flush performed */ 619 finish_started, /* finish started, need only more output at next deflate */ 620 finish_done /* finish done, accept no more input or output */ 621} block_state; 622 623typedef block_state (*compress_func) OF((deflate_state *s, int flush)); 624/* Compression function. Returns the block state after the call. */ 625 626local void fill_window OF((deflate_state *s)); 627local block_state deflate_stored OF((deflate_state *s, int flush)); 628local block_state deflate_fast OF((deflate_state *s, int flush)); 629local block_state deflate_slow OF((deflate_state *s, int flush)); 630local void lm_init OF((deflate_state *s)); 631local void putShortMSB OF((deflate_state *s, uInt b)); 632local void flush_pending OF((z_streamp strm)); 633local int read_buf OF((z_streamp strm, charf *buf, unsigned size)); 634#ifdef ASMV 635 void match_init OF((void)); /* asm code initialization */ 636 uInt longest_match OF((deflate_state *s, IPos cur_match)); 637#else 638local uInt longest_match OF((deflate_state *s, IPos cur_match)); 639#endif 640 641#ifdef DEBUG_ZLIB 642local void check_match OF((deflate_state *s, IPos start, IPos match, 643 int length)); 644#endif 645 646/* =========================================================================== 647 * Local data 648 */ 649 650#define NIL 0 651/* Tail of hash chains */ 652 653#ifndef TOO_FAR 654# define TOO_FAR 4096 655#endif 656/* Matches of length 3 are discarded if their distance exceeds TOO_FAR */ 657 658#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1) 659/* Minimum amount of lookahead, except at the end of the input file. 660 * See deflate.c for comments about the MIN_MATCH+1. 661 */ 662 663/* Values for max_lazy_match, good_match and max_chain_length, depending on 664 * the desired pack level (0..9). The values given below have been tuned to 665 * exclude worst case performance for pathological files. Better values may be 666 * found for specific files. 667 */ 668typedef struct config_s { 669 ush good_length; /* reduce lazy search above this match length */ 670 ush max_lazy; /* do not perform lazy search above this match length */ 671 ush nice_length; /* quit search above this match length */ 672 ush max_chain; 673 compress_func func; 674} config; 675 676local config configuration_table[10] = { 677/* good lazy nice chain */ 678/* 0 */ {0, 0, 0, 0, deflate_stored}, /* store only */ 679/* 1 */ {4, 4, 8, 4, deflate_fast}, /* maximum speed, no lazy matches */ 680/* 2 */ {4, 5, 16, 8, deflate_fast}, 681/* 3 */ {4, 6, 32, 32, deflate_fast}, 682 683/* 4 */ {4, 4, 16, 16, deflate_slow}, /* lazy matches */ 684/* 5 */ {8, 16, 32, 32, deflate_slow}, 685/* 6 */ {8, 16, 128, 128, deflate_slow}, 686/* 7 */ {8, 32, 128, 256, deflate_slow}, 687/* 8 */ {32, 128, 258, 1024, deflate_slow}, 688/* 9 */ {32, 258, 258, 4096, deflate_slow}}; /* maximum compression */ 689 690/* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4 691 * For deflate_fast() (levels <= 3) good is ignored and lazy has a different 692 * meaning. 693 */ 694 695#define EQUAL 0 696/* result of memcmp for equal strings */ 697 698#ifndef NO_DUMMY_DECL 699struct static_tree_desc_s {int dummy;}; /* for buggy compilers */ 700#endif 701 702/* =========================================================================== 703 * Update a hash value with the given input byte 704 * IN assertion: all calls to to UPDATE_HASH are made with consecutive 705 * input characters, so that a running hash key can be computed from the 706 * previous key instead of complete recalculation each time. 707 */ 708#define UPDATE_HASH(s,h,c) (h = (((h)<<s->hash_shift) ^ (c)) & s->hash_mask) 709 710 711/* =========================================================================== 712 * Insert string str in the dictionary and set match_head to the previous head 713 * of the hash chain (the most recent string with same hash key). Return 714 * the previous length of the hash chain. 715 * IN assertion: all calls to to INSERT_STRING are made with consecutive 716 * input characters and the first MIN_MATCH bytes of str are valid 717 * (except for the last MIN_MATCH-1 bytes of the input file). 718 */ 719#define INSERT_STRING(s, str, match_head) \ 720 (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \ 721 s->prev[(str) & s->w_mask] = match_head = s->head[s->ins_h], \ 722 s->head[s->ins_h] = (Pos)(str)) 723 724/* =========================================================================== 725 * Initialize the hash table (avoiding 64K overflow for 16 bit systems). 726 * prev[] will be initialized on the fly. 727 */ 728#define CLEAR_HASH(s) \ 729 s->head[s->hash_size-1] = NIL; \ 730 zmemzero((charf *)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head)); 731 732/* ========================================================================= */ 733int deflateInit_(strm, level, version, stream_size) 734 z_streamp strm; 735 int level; 736 const char *version; 737 int stream_size; 738{ 739 return deflateInit2_(strm, level, Z_DEFLATED, MAX_WBITS, DEF_MEM_LEVEL, 740 Z_DEFAULT_STRATEGY, version, stream_size); 741 /* To do: ignore strm->next_in if we use it as window */ 742} 743 744/* ========================================================================= */ 745int deflateInit2_(strm, level, method, windowBits, memLevel, strategy, 746 version, stream_size) 747 z_streamp strm; 748 int level; 749 int method; 750 int windowBits; 751 int memLevel; 752 int strategy; 753 const char *version; 754 int stream_size; 755{ 756 deflate_state *s; 757 int noheader = 0; 758 static char* my_version = ZLIB_VERSION; 759 760 ushf *overlay; 761 /* We overlay pending_buf and d_buf+l_buf. This works since the average 762 * output size for (length,distance) codes is <= 24 bits. 763 */ 764 765 if (version == Z_NULL || version[0] != my_version[0] || 766 stream_size != sizeof(z_stream)) { 767 return Z_VERSION_ERROR; 768 } 769 if (strm == Z_NULL) return Z_STREAM_ERROR; 770 771 strm->msg = Z_NULL; 772#ifndef NO_ZCFUNCS 773 if (strm->zalloc == Z_NULL) { 774 strm->zalloc = zcalloc; 775 strm->opaque = (voidpf)0; 776 } 777 if (strm->zfree == Z_NULL) strm->zfree = zcfree; 778#endif 779 780 if (level == Z_DEFAULT_COMPRESSION) level = 6; 781 782 if (windowBits < 0) { /* undocumented feature: suppress zlib header */ 783 noheader = 1; 784 windowBits = -windowBits; 785 } 786 if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED || 787 windowBits < 9 || windowBits > 15 || level < 0 || level > 9 || 788 strategy < 0 || strategy > Z_HUFFMAN_ONLY) { 789 return Z_STREAM_ERROR; 790 } 791 s = (deflate_state *) ZALLOC(strm, 1, sizeof(deflate_state)); 792 if (s == Z_NULL) return Z_MEM_ERROR; 793 strm->state = (struct internal_state FAR *)s; 794 s->strm = strm; 795 796 s->noheader = noheader; 797 s->w_bits = windowBits; 798 s->w_size = 1 << s->w_bits; 799 s->w_mask = s->w_size - 1; 800 801 s->hash_bits = memLevel + 7; 802 s->hash_size = 1 << s->hash_bits; 803 s->hash_mask = s->hash_size - 1; 804 s->hash_shift = ((s->hash_bits+MIN_MATCH-1)/MIN_MATCH); 805 806 s->window = (Bytef *) ZALLOC(strm, s->w_size, 2*sizeof(Byte)); 807 s->prev = (Posf *) ZALLOC(strm, s->w_size, sizeof(Pos)); 808 s->head = (Posf *) ZALLOC(strm, s->hash_size, sizeof(Pos)); 809 810 s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */ 811 812 overlay = (ushf *) ZALLOC(strm, s->lit_bufsize, sizeof(ush)+2); 813 s->pending_buf = (uchf *) overlay; 814 s->pending_buf_size = (ulg)s->lit_bufsize * (sizeof(ush)+2L); 815 816 if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL || 817 s->pending_buf == Z_NULL) { 818 strm->msg = (const char*)ERR_MSG(Z_MEM_ERROR); 819 deflateEnd (strm); 820 return Z_MEM_ERROR; 821 } 822 s->d_buf = overlay + s->lit_bufsize/sizeof(ush); 823 s->l_buf = s->pending_buf + (1+sizeof(ush))*s->lit_bufsize; 824 825 s->level = level; 826 s->strategy = strategy; 827 s->method = (Byte)method; 828 829 return deflateReset(strm); 830} 831 832/* ========================================================================= */ 833int deflateSetDictionary (strm, dictionary, dictLength) 834 z_streamp strm; 835 const Bytef *dictionary; 836 uInt dictLength; 837{ 838 deflate_state *s; 839 uInt length = dictLength; 840 uInt n; 841 IPos hash_head = 0; 842 843 if (strm == Z_NULL || strm->state == Z_NULL || dictionary == Z_NULL) 844 return Z_STREAM_ERROR; 845 846 s = (deflate_state *) strm->state; 847 if (s->status != INIT_STATE) return Z_STREAM_ERROR; 848 849 strm->adler = adler32(strm->adler, dictionary, dictLength); 850 851 if (length < MIN_MATCH) return Z_OK; 852 if (length > MAX_DIST(s)) { 853 length = MAX_DIST(s); 854#ifndef USE_DICT_HEAD 855 dictionary += dictLength - length; /* use the tail of the dictionary */ 856#endif 857 } 858 zmemcpy((charf *)s->window, dictionary, length); 859 s->strstart = length; 860 s->block_start = (long)length; 861 862 /* Insert all strings in the hash table (except for the last two bytes). 863 * s->lookahead stays null, so s->ins_h will be recomputed at the next 864 * call of fill_window. 865 */ 866 s->ins_h = s->window[0]; 867 UPDATE_HASH(s, s->ins_h, s->window[1]); 868 for (n = 0; n <= length - MIN_MATCH; n++) { 869 INSERT_STRING(s, n, hash_head); 870 } 871 if (hash_head) hash_head = 0; /* to make compiler happy */ 872 return Z_OK; 873} 874 875/* ========================================================================= */ 876int deflateReset (strm) 877 z_streamp strm; 878{ 879 deflate_state *s; 880 881 if (strm == Z_NULL || strm->state == Z_NULL || 882 strm->zalloc == Z_NULL || strm->zfree == Z_NULL) return Z_STREAM_ERROR; 883 884 strm->total_in = strm->total_out = 0; 885 strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */ 886 strm->data_type = Z_UNKNOWN; 887 888 s = (deflate_state *)strm->state; 889 s->pending = 0; 890 s->pending_out = s->pending_buf; 891 892 if (s->noheader < 0) { 893 s->noheader = 0; /* was set to -1 by deflate(..., Z_FINISH); */ 894 } 895 s->status = s->noheader ? BUSY_STATE : INIT_STATE; 896 strm->adler = 1; 897 s->last_flush = Z_NO_FLUSH; 898 899 _tr_init(s); 900 lm_init(s); 901 902 return Z_OK; 903} 904 905/* ========================================================================= */ 906int deflateParams(strm, level, strategy) 907 z_streamp strm; 908 int level; 909 int strategy; 910{ 911 deflate_state *s; 912 compress_func func; 913 int err = Z_OK; 914 915 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; 916 s = (deflate_state *) strm->state; 917 918 if (level == Z_DEFAULT_COMPRESSION) { 919 level = 6; 920 } 921 if (level < 0 || level > 9 || strategy < 0 || strategy > Z_HUFFMAN_ONLY) { 922 return Z_STREAM_ERROR; 923 } 924 func = configuration_table[s->level].func; 925 926 if (func != configuration_table[level].func && strm->total_in != 0) { 927 /* Flush the last buffer: */ 928 err = deflate(strm, Z_PARTIAL_FLUSH); 929 } 930 if (s->level != level) { 931 s->level = level; 932 s->max_lazy_match = configuration_table[level].max_lazy; 933 s->good_match = configuration_table[level].good_length; 934 s->nice_match = configuration_table[level].nice_length; 935 s->max_chain_length = configuration_table[level].max_chain; 936 } 937 s->strategy = strategy; 938 return err; 939} 940 941/* ========================================================================= 942 * Put a short in the pending buffer. The 16-bit value is put in MSB order. 943 * IN assertion: the stream state is correct and there is enough room in 944 * pending_buf. 945 */ 946local void putShortMSB (s, b) 947 deflate_state *s; 948 uInt b; 949{ 950 put_byte(s, (Byte)(b >> 8)); 951 put_byte(s, (Byte)(b & 0xff)); 952} 953 954/* ========================================================================= 955 * Flush as much pending output as possible. All deflate() output goes 956 * through this function so some applications may wish to modify it 957 * to avoid allocating a large strm->next_out buffer and copying into it. 958 * (See also read_buf()). 959 */ 960local void flush_pending(strm) 961 z_streamp strm; 962{ 963 deflate_state *s = (deflate_state *) strm->state; 964 unsigned len = s->pending; 965 966 if (len > strm->avail_out) len = strm->avail_out; 967 if (len == 0) return; 968 969 if (strm->next_out != Z_NULL) { 970 zmemcpy(strm->next_out, s->pending_out, len); 971 strm->next_out += len; 972 } 973 s->pending_out += len; 974 strm->total_out += len; 975 strm->avail_out -= len; 976 s->pending -= len; 977 if (s->pending == 0) { 978 s->pending_out = s->pending_buf; 979 } 980} 981 982/* ========================================================================= */ 983int deflate (strm, flush) 984 z_streamp strm; 985 int flush; 986{ 987 int old_flush; /* value of flush param for previous deflate call */ 988 deflate_state *s; 989 990 if (strm == Z_NULL || strm->state == Z_NULL || 991 flush > Z_FINISH || flush < 0) { 992 return Z_STREAM_ERROR; 993 } 994 s = (deflate_state *) strm->state; 995 996 if ((strm->next_in == Z_NULL && strm->avail_in != 0) || 997 (s->status == FINISH_STATE && flush != Z_FINISH)) { 998 ERR_RETURN(strm, Z_STREAM_ERROR); 999 } 1000 if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR); 1001 1002 s->strm = strm; /* just in case */ 1003 old_flush = s->last_flush; 1004 s->last_flush = flush; 1005 1006 /* Write the zlib header */ 1007 if (s->status == INIT_STATE) { 1008 1009 uInt header = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8; 1010 uInt level_flags = (s->level-1) >> 1; 1011 1012 if (level_flags > 3) level_flags = 3; 1013 header |= (level_flags << 6); 1014 if (s->strstart != 0) header |= PRESET_DICT; 1015 header += 31 - (header % 31); 1016 1017 s->status = BUSY_STATE; 1018 putShortMSB(s, header); 1019 1020 /* Save the adler32 of the preset dictionary: */ 1021 if (s->strstart != 0) { 1022 putShortMSB(s, (uInt)(strm->adler >> 16)); 1023 putShortMSB(s, (uInt)(strm->adler & 0xffff)); 1024 } 1025 strm->adler = 1L; 1026 } 1027 1028 /* Flush as much pending output as possible */ 1029 if (s->pending != 0) { 1030 flush_pending(strm); 1031 if (strm->avail_out == 0) { 1032 /* Since avail_out is 0, deflate will be called again with 1033 * more output space, but possibly with both pending and 1034 * avail_in equal to zero. There won't be anything to do, 1035 * but this is not an error situation so make sure we 1036 * return OK instead of BUF_ERROR at next call of deflate: 1037 */ 1038 s->last_flush = -1; 1039 return Z_OK; 1040 } 1041 1042 /* Make sure there is something to do and avoid duplicate consecutive 1043 * flushes. For repeated and useless calls with Z_FINISH, we keep 1044 * returning Z_STREAM_END instead of Z_BUFF_ERROR. 1045 */ 1046 } else if (strm->avail_in == 0 && flush <= old_flush && 1047 flush != Z_FINISH) { 1048 ERR_RETURN(strm, Z_BUF_ERROR); 1049 } 1050 1051 /* User must not provide more input after the first FINISH: */ 1052 if (s->status == FINISH_STATE && strm->avail_in != 0) { 1053 ERR_RETURN(strm, Z_BUF_ERROR); 1054 } 1055 1056 /* Start a new block or continue the current one. 1057 */ 1058 if (strm->avail_in != 0 || s->lookahead != 0 || 1059 (flush != Z_NO_FLUSH && s->status != FINISH_STATE)) { 1060 block_state bstate; 1061 1062 bstate = (*(configuration_table[s->level].func))(s, flush); 1063 1064 if (bstate == finish_started || bstate == finish_done) { 1065 s->status = FINISH_STATE; 1066 } 1067 if (bstate == need_more || bstate == finish_started) { 1068 if (strm->avail_out == 0) { 1069 s->last_flush = -1; /* avoid BUF_ERROR next call, see above */ 1070 } 1071 return Z_OK; 1072 /* If flush != Z_NO_FLUSH && avail_out == 0, the next call 1073 * of deflate should use the same flush parameter to make sure 1074 * that the flush is complete. So we don't have to output an 1075 * empty block here, this will be done at next call. This also 1076 * ensures that for a very small output buffer, we emit at most 1077 * one empty block. 1078 */ 1079 } 1080 if (bstate == block_done) { 1081 if (flush == Z_PARTIAL_FLUSH) { 1082 _tr_align(s); 1083 } else if (flush == Z_PACKET_FLUSH) { 1084 /* Output just the 3-bit `stored' block type value, 1085 but not a zero length. */ 1086 _tr_stored_type_only(s); 1087 } else { /* FULL_FLUSH or SYNC_FLUSH */ 1088 _tr_stored_block(s, (char*)0, 0L, 0); 1089 /* For a full flush, this empty block will be recognized 1090 * as a special marker by inflate_sync(). 1091 */ 1092 if (flush == Z_FULL_FLUSH) { 1093 CLEAR_HASH(s); /* forget history */ 1094 } 1095 } 1096 flush_pending(strm); 1097 if (strm->avail_out == 0) { 1098 s->last_flush = -1; /* avoid BUF_ERROR at next call, see above */ 1099 return Z_OK; 1100 } 1101 } 1102 } 1103 Assert(strm->avail_out > 0, "bug2"); 1104 1105 if (flush != Z_FINISH) return Z_OK; 1106 if (s->noheader) return Z_STREAM_END; 1107 1108 /* Write the zlib trailer (adler32) */ 1109 putShortMSB(s, (uInt)(strm->adler >> 16)); 1110 putShortMSB(s, (uInt)(strm->adler & 0xffff)); 1111 flush_pending(strm); 1112 /* If avail_out is zero, the application will call deflate again 1113 * to flush the rest. 1114 */ 1115 s->noheader = -1; /* write the trailer only once! */ 1116 return s->pending != 0 ? Z_OK : Z_STREAM_END; 1117} 1118 1119/* ========================================================================= */ 1120int deflateEnd (strm) 1121 z_streamp strm; 1122{ 1123 int status; 1124 deflate_state *s; 1125 1126 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; 1127 s = (deflate_state *) strm->state; 1128 1129 status = s->status; 1130 if (status != INIT_STATE && status != BUSY_STATE && 1131 status != FINISH_STATE) { 1132 return Z_STREAM_ERROR; 1133 } 1134 1135 /* Deallocate in reverse order of allocations: */ 1136 TRY_FREE(strm, s->pending_buf); 1137 TRY_FREE(strm, s->head); 1138 TRY_FREE(strm, s->prev); 1139 TRY_FREE(strm, s->window); 1140 1141 ZFREE(strm, s); 1142 strm->state = Z_NULL; 1143 1144 return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK; 1145} 1146 1147/* ========================================================================= 1148 * Copy the source state to the destination state. 1149 */ 1150int deflateCopy (dest, source) 1151 z_streamp dest; 1152 z_streamp source; 1153{ 1154 deflate_state *ds; 1155 deflate_state *ss; 1156 ushf *overlay; 1157 1158 if (source == Z_NULL || dest == Z_NULL || source->state == Z_NULL) 1159 return Z_STREAM_ERROR; 1160 ss = (deflate_state *) source->state; 1161 1162 zmemcpy(dest, source, sizeof(*dest)); 1163 1164 ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state)); 1165 if (ds == Z_NULL) return Z_MEM_ERROR; 1166 dest->state = (struct internal_state FAR *) ds; 1167 zmemcpy(ds, ss, sizeof(*ds)); 1168 ds->strm = dest; 1169 1170 ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte)); 1171 ds->prev = (Posf *) ZALLOC(dest, ds->w_size, sizeof(Pos)); 1172 ds->head = (Posf *) ZALLOC(dest, ds->hash_size, sizeof(Pos)); 1173 overlay = (ushf *) ZALLOC(dest, ds->lit_bufsize, sizeof(ush)+2); 1174 ds->pending_buf = (uchf *) overlay; 1175 1176 if (ds->window == Z_NULL || ds->prev == Z_NULL || ds->head == Z_NULL || 1177 ds->pending_buf == Z_NULL) { 1178 deflateEnd (dest); 1179 return Z_MEM_ERROR; 1180 } 1181 /* ??? following zmemcpy doesn't work for 16-bit MSDOS */ 1182 zmemcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte)); 1183 zmemcpy(ds->prev, ss->prev, ds->w_size * sizeof(Pos)); 1184 zmemcpy(ds->head, ss->head, ds->hash_size * sizeof(Pos)); 1185 zmemcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size); 1186 1187 ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf); 1188 ds->d_buf = overlay + ds->lit_bufsize/sizeof(ush); 1189 ds->l_buf = ds->pending_buf + (1+sizeof(ush))*ds->lit_bufsize; 1190 1191 ds->l_desc.dyn_tree = ds->dyn_ltree; 1192 ds->d_desc.dyn_tree = ds->dyn_dtree; 1193 ds->bl_desc.dyn_tree = ds->bl_tree; 1194 1195 return Z_OK; 1196} 1197 1198/* =========================================================================== 1199 * Return the number of bytes of output which are immediately available 1200 * for output from the decompressor. 1201 */ 1202int deflateOutputPending (strm) 1203 z_streamp strm; 1204{ 1205 if (strm == Z_NULL || strm->state == Z_NULL) return 0; 1206 1207 return ((deflate_state *)(strm->state))->pending; 1208} 1209 1210/* =========================================================================== 1211 * Read a new buffer from the current input stream, update the adler32 1212 * and total number of bytes read. All deflate() input goes through 1213 * this function so some applications may wish to modify it to avoid 1214 * allocating a large strm->next_in buffer and copying from it. 1215 * (See also flush_pending()). 1216 */ 1217local int read_buf(strm, buf, size) 1218 z_streamp strm; 1219 charf *buf; 1220 unsigned size; 1221{ 1222 unsigned len = strm->avail_in; 1223 1224 if (len > size) len = size; 1225 if (len == 0) return 0; 1226 1227 strm->avail_in -= len; 1228 1229 if (!((deflate_state *)(strm->state))->noheader) { 1230 strm->adler = adler32(strm->adler, strm->next_in, len); 1231 } 1232 zmemcpy(buf, strm->next_in, len); 1233 strm->next_in += len; 1234 strm->total_in += len; 1235 1236 return (int)len; 1237} 1238 1239/* =========================================================================== 1240 * Initialize the "longest match" routines for a new zlib stream 1241 */ 1242local void lm_init (s) 1243 deflate_state *s; 1244{ 1245 s->window_size = (ulg)2L*s->w_size; 1246 1247 CLEAR_HASH(s); 1248 1249 /* Set the default configuration parameters: 1250 */ 1251 s->max_lazy_match = configuration_table[s->level].max_lazy; 1252 s->good_match = configuration_table[s->level].good_length; 1253 s->nice_match = configuration_table[s->level].nice_length; 1254 s->max_chain_length = configuration_table[s->level].max_chain; 1255 1256 s->strstart = 0; 1257 s->block_start = 0L; 1258 s->lookahead = 0; 1259 s->match_length = s->prev_length = MIN_MATCH-1; 1260 s->match_available = 0; 1261 s->ins_h = 0; 1262#ifdef ASMV 1263 match_init(); /* initialize the asm code */ 1264#endif 1265} 1266 1267/* =========================================================================== 1268 * Set match_start to the longest match starting at the given string and 1269 * return its length. Matches shorter or equal to prev_length are discarded, 1270 * in which case the result is equal to prev_length and match_start is 1271 * garbage. 1272 * IN assertions: cur_match is the head of the hash chain for the current 1273 * string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1 1274 * OUT assertion: the match length is not greater than s->lookahead. 1275 */ 1276#ifndef ASMV 1277/* For 80x86 and 680x0, an optimized version will be provided in match.asm or 1278 * match.S. The code will be functionally equivalent. 1279 */ 1280local uInt longest_match(s, cur_match) 1281 deflate_state *s; 1282 IPos cur_match; /* current match */ 1283{ 1284 unsigned chain_length = s->max_chain_length;/* max hash chain length */ 1285 register Bytef *scan = s->window + s->strstart; /* current string */ 1286 register Bytef *match; /* matched string */ 1287 register int len; /* length of current match */ 1288 int best_len = s->prev_length; /* best match length so far */ 1289 int nice_match = s->nice_match; /* stop if match long enough */ 1290 IPos limit = s->strstart > (IPos)MAX_DIST(s) ? 1291 s->strstart - (IPos)MAX_DIST(s) : NIL; 1292 /* Stop when cur_match becomes <= limit. To simplify the code, 1293 * we prevent matches with the string of window index 0. 1294 */ 1295 Posf *prev = s->prev; 1296 uInt wmask = s->w_mask; 1297 1298#ifdef UNALIGNED_OK 1299 /* Compare two bytes at a time. Note: this is not always beneficial. 1300 * Try with and without -DUNALIGNED_OK to check. 1301 */ 1302 register Bytef *strend = s->window + s->strstart + MAX_MATCH - 1; 1303 register ush scan_start = *(ushf*)scan; 1304 register ush scan_end = *(ushf*)(scan+best_len-1); 1305#else 1306 register Bytef *strend = s->window + s->strstart + MAX_MATCH; 1307 register Byte scan_end1 = scan[best_len-1]; 1308 register Byte scan_end = scan[best_len]; 1309#endif 1310 1311 /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16. 1312 * It is easy to get rid of this optimization if necessary. 1313 */ 1314 Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever"); 1315 1316 /* Do not waste too much time if we already have a good match: */ 1317 if (s->prev_length >= s->good_match) { 1318 chain_length >>= 2; 1319 } 1320 /* Do not look for matches beyond the end of the input. This is necessary 1321 * to make deflate deterministic. 1322 */ 1323 if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead; 1324 1325 Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead"); 1326 1327 do { 1328 Assert(cur_match < s->strstart, "no future"); 1329 match = s->window + cur_match; 1330 1331 /* Skip to next match if the match length cannot increase 1332 * or if the match length is less than 2: 1333 */ 1334#if (defined(UNALIGNED_OK) && MAX_MATCH == 258) 1335 /* This code assumes sizeof(unsigned short) == 2. Do not use 1336 * UNALIGNED_OK if your compiler uses a different size. 1337 */ 1338 if (*(ushf*)(match+best_len-1) != scan_end || 1339 *(ushf*)match != scan_start) continue; 1340 1341 /* It is not necessary to compare scan[2] and match[2] since they are 1342 * always equal when the other bytes match, given that the hash keys 1343 * are equal and that HASH_BITS >= 8. Compare 2 bytes at a time at 1344 * strstart+3, +5, ... up to strstart+257. We check for insufficient 1345 * lookahead only every 4th comparison; the 128th check will be made 1346 * at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is 1347 * necessary to put more guard bytes at the end of the window, or 1348 * to check more often for insufficient lookahead. 1349 */ 1350 Assert(scan[2] == match[2], "scan[2]?"); 1351 scan++, match++; 1352 do { 1353 } while (*(ushf*)(scan+=2) == *(ushf*)(match+=2) && 1354 *(ushf*)(scan+=2) == *(ushf*)(match+=2) && 1355 *(ushf*)(scan+=2) == *(ushf*)(match+=2) && 1356 *(ushf*)(scan+=2) == *(ushf*)(match+=2) && 1357 scan < strend); 1358 /* The funny "do {}" generates better code on most compilers */ 1359 1360 /* Here, scan <= window+strstart+257 */ 1361 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan"); 1362 if (*scan == *match) scan++; 1363 1364 len = (MAX_MATCH - 1) - (int)(strend-scan); 1365 scan = strend - (MAX_MATCH-1); 1366 1367#else /* UNALIGNED_OK */ 1368 1369 if (match[best_len] != scan_end || 1370 match[best_len-1] != scan_end1 || 1371 *match != *scan || 1372 *++match != scan[1]) continue; 1373 1374 /* The check at best_len-1 can be removed because it will be made 1375 * again later. (This heuristic is not always a win.) 1376 * It is not necessary to compare scan[2] and match[2] since they 1377 * are always equal when the other bytes match, given that 1378 * the hash keys are equal and that HASH_BITS >= 8. 1379 */ 1380 scan += 2, match++; 1381 Assert(*scan == *match, "match[2]?"); 1382 1383 /* We check for insufficient lookahead only every 8th comparison; 1384 * the 256th check will be made at strstart+258. 1385 */ 1386 do { 1387 } while (*++scan == *++match && *++scan == *++match && 1388 *++scan == *++match && *++scan == *++match && 1389 *++scan == *++match && *++scan == *++match && 1390 *++scan == *++match && *++scan == *++match && 1391 scan < strend); 1392 1393 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan"); 1394 1395 len = MAX_MATCH - (int)(strend - scan); 1396 scan = strend - MAX_MATCH; 1397 1398#endif /* UNALIGNED_OK */ 1399 1400 if (len > best_len) { 1401 s->match_start = cur_match; 1402 best_len = len; 1403 if (len >= nice_match) break; 1404#ifdef UNALIGNED_OK 1405 scan_end = *(ushf*)(scan+best_len-1); 1406#else 1407 scan_end1 = scan[best_len-1]; 1408 scan_end = scan[best_len]; 1409#endif 1410 } 1411 } while ((cur_match = prev[cur_match & wmask]) > limit 1412 && --chain_length != 0); 1413 1414 if ((uInt)best_len <= s->lookahead) return best_len; 1415 return s->lookahead; 1416} 1417#endif /* ASMV */ 1418 1419#ifdef DEBUG_ZLIB 1420/* =========================================================================== 1421 * Check that the match at match_start is indeed a match. 1422 */ 1423local void check_match(s, start, match, length) 1424 deflate_state *s; 1425 IPos start, match; 1426 int length; 1427{ 1428 /* check that the match is indeed a match */ 1429 if (zmemcmp((charf *)s->window + match, 1430 (charf *)s->window + start, length) != EQUAL) { 1431 fprintf(stderr, " start %u, match %u, length %d\n", 1432 start, match, length); 1433 do { 1434 fprintf(stderr, "%c%c", s->window[match++], s->window[start++]); 1435 } while (--length != 0); 1436 z_error("invalid match"); 1437 } 1438 if (z_verbose > 1) { 1439 fprintf(stderr,"\\[%d,%d]", start-match, length); 1440 do { putc(s->window[start++], stderr); } while (--length != 0); 1441 } 1442} 1443#else 1444# define check_match(s, start, match, length) 1445#endif 1446 1447/* =========================================================================== 1448 * Fill the window when the lookahead becomes insufficient. 1449 * Updates strstart and lookahead. 1450 * 1451 * IN assertion: lookahead < MIN_LOOKAHEAD 1452 * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD 1453 * At least one byte has been read, or avail_in == 0; reads are 1454 * performed for at least two bytes (required for the zip translate_eol 1455 * option -- not supported here). 1456 */ 1457local void fill_window(s) 1458 deflate_state *s; 1459{ 1460 register unsigned n, m; 1461 register Posf *p; 1462 unsigned more; /* Amount of free space at the end of the window. */ 1463 uInt wsize = s->w_size; 1464 1465 do { 1466 more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart); 1467 1468 /* Deal with !@#$% 64K limit: */ 1469 if (more == 0 && s->strstart == 0 && s->lookahead == 0) { 1470 more = wsize; 1471 1472 } else if (more == (unsigned)(-1)) { 1473 /* Very unlikely, but possible on 16 bit machine if strstart == 0 1474 * and lookahead == 1 (input done one byte at time) 1475 */ 1476 more--; 1477 1478 /* If the window is almost full and there is insufficient lookahead, 1479 * move the upper half to the lower one to make room in the upper half. 1480 */ 1481 } else if (s->strstart >= wsize+MAX_DIST(s)) { 1482 1483 zmemcpy((charf *)s->window, (charf *)s->window+wsize, 1484 (unsigned)wsize); 1485 s->match_start -= wsize; 1486 s->strstart -= wsize; /* we now have strstart >= MAX_DIST */ 1487 s->block_start -= (long) wsize; 1488 1489 /* Slide the hash table (could be avoided with 32 bit values 1490 at the expense of memory usage). We slide even when level == 0 1491 to keep the hash table consistent if we switch back to level > 0 1492 later. (Using level 0 permanently is not an optimal usage of 1493 zlib, so we don't care about this pathological case.) 1494 */ 1495 n = s->hash_size; 1496 p = &s->head[n]; 1497 do { 1498 m = *--p; 1499 *p = (Pos)(m >= wsize ? m-wsize : NIL); 1500 } while (--n); 1501 1502 n = wsize; 1503 p = &s->prev[n]; 1504 do { 1505 m = *--p; 1506 *p = (Pos)(m >= wsize ? m-wsize : NIL); 1507 /* If n is not on any hash chain, prev[n] is garbage but 1508 * its value will never be used. 1509 */ 1510 } while (--n); 1511 more += wsize; 1512 } 1513 if (s->strm->avail_in == 0) return; 1514 1515 /* If there was no sliding: 1516 * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 && 1517 * more == window_size - lookahead - strstart 1518 * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1) 1519 * => more >= window_size - 2*WSIZE + 2 1520 * In the BIG_MEM or MMAP case (not yet supported), 1521 * window_size == input_size + MIN_LOOKAHEAD && 1522 * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD. 1523 * Otherwise, window_size == 2*WSIZE so more >= 2. 1524 * If there was sliding, more >= WSIZE. So in all cases, more >= 2. 1525 */ 1526 Assert(more >= 2, "more < 2"); 1527 1528 n = read_buf(s->strm, (charf *)s->window + s->strstart + s->lookahead, 1529 more); 1530 s->lookahead += n; 1531 1532 /* Initialize the hash value now that we have some input: */ 1533 if (s->lookahead >= MIN_MATCH) { 1534 s->ins_h = s->window[s->strstart]; 1535 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]); 1536#if MIN_MATCH != 3 1537 Call UPDATE_HASH() MIN_MATCH-3 more times 1538#endif 1539 } 1540 /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage, 1541 * but this is not important since only literal bytes will be emitted. 1542 */ 1543 1544 } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0); 1545} 1546 1547/* =========================================================================== 1548 * Flush the current block, with given end-of-file flag. 1549 * IN assertion: strstart is set to the end of the current match. 1550 */ 1551#define FLUSH_BLOCK_ONLY(s, eof) { \ 1552 _tr_flush_block(s, (s->block_start >= 0L ? \ 1553 (charf *)&s->window[(unsigned)s->block_start] : \ 1554 (charf *)Z_NULL), \ 1555 (ulg)((long)s->strstart - s->block_start), \ 1556 (eof)); \ 1557 s->block_start = s->strstart; \ 1558 flush_pending(s->strm); \ 1559 Tracev((stderr,"[FLUSH]")); \ 1560} 1561 1562/* Same but force premature exit if necessary. */ 1563#define FLUSH_BLOCK(s, eof) { \ 1564 FLUSH_BLOCK_ONLY(s, eof); \ 1565 if (s->strm->avail_out == 0) return (eof) ? finish_started : need_more; \ 1566} 1567 1568/* =========================================================================== 1569 * Copy without compression as much as possible from the input stream, return 1570 * the current block state. 1571 * This function does not insert new strings in the dictionary since 1572 * uncompressible data is probably not useful. This function is used 1573 * only for the level=0 compression option. 1574 * NOTE: this function should be optimized to avoid extra copying from 1575 * window to pending_buf. 1576 */ 1577local block_state deflate_stored(s, flush) 1578 deflate_state *s; 1579 int flush; 1580{ 1581 /* Stored blocks are limited to 0xffff bytes, pending_buf is limited 1582 * to pending_buf_size, and each stored block has a 5 byte header: 1583 */ 1584 ulg max_block_size = 0xffff; 1585 ulg max_start; 1586 1587 if (max_block_size > s->pending_buf_size - 5) { 1588 max_block_size = s->pending_buf_size - 5; 1589 } 1590 1591 /* Copy as much as possible from input to output: */ 1592 for (;;) { 1593 /* Fill the window as much as possible: */ 1594 if (s->lookahead <= 1) { 1595 1596 Assert(s->strstart < s->w_size+MAX_DIST(s) || 1597 s->block_start >= (long)s->w_size, "slide too late"); 1598 1599 fill_window(s); 1600 if (s->lookahead == 0 && flush == Z_NO_FLUSH) return need_more; 1601 1602 if (s->lookahead == 0) break; /* flush the current block */ 1603 } 1604 Assert(s->block_start >= 0L, "block gone"); 1605 1606 s->strstart += s->lookahead; 1607 s->lookahead = 0; 1608 1609 /* Emit a stored block if pending_buf will be full: */ 1610 max_start = s->block_start + max_block_size; 1611 if (s->strstart == 0 || (ulg)s->strstart >= max_start) { 1612 /* strstart == 0 is possible when wraparound on 16-bit machine */ 1613 s->lookahead = (uInt)(s->strstart - max_start); 1614 s->strstart = (uInt)max_start; 1615 FLUSH_BLOCK(s, 0); 1616 } 1617 /* Flush if we may have to slide, otherwise block_start may become 1618 * negative and the data will be gone: 1619 */ 1620 if (s->strstart - (uInt)s->block_start >= MAX_DIST(s)) { 1621 FLUSH_BLOCK(s, 0); 1622 } 1623 } 1624 FLUSH_BLOCK(s, flush == Z_FINISH); 1625 return flush == Z_FINISH ? finish_done : block_done; 1626} 1627 1628/* =========================================================================== 1629 * Compress as much as possible from the input stream, return the current 1630 * block state. 1631 * This function does not perform lazy evaluation of matches and inserts 1632 * new strings in the dictionary only for unmatched strings or for short 1633 * matches. It is used only for the fast compression options. 1634 */ 1635local block_state deflate_fast(s, flush) 1636 deflate_state *s; 1637 int flush; 1638{ 1639 IPos hash_head = NIL; /* head of the hash chain */ 1640 int bflush; /* set if current block must be flushed */ 1641 1642 for (;;) { 1643 /* Make sure that we always have enough lookahead, except 1644 * at the end of the input file. We need MAX_MATCH bytes 1645 * for the next match, plus MIN_MATCH bytes to insert the 1646 * string following the next match. 1647 */ 1648 if (s->lookahead < MIN_LOOKAHEAD) { 1649 fill_window(s); 1650 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) { 1651 return need_more; 1652 } 1653 if (s->lookahead == 0) break; /* flush the current block */ 1654 } 1655 1656 /* Insert the string window[strstart .. strstart+2] in the 1657 * dictionary, and set hash_head to the head of the hash chain: 1658 */ 1659 if (s->lookahead >= MIN_MATCH) { 1660 INSERT_STRING(s, s->strstart, hash_head); 1661 } 1662 1663 /* Find the longest match, discarding those <= prev_length. 1664 * At this point we have always match_length < MIN_MATCH 1665 */ 1666 if (hash_head != NIL && s->strstart - hash_head <= MAX_DIST(s)) { 1667 /* To simplify the code, we prevent matches with the string 1668 * of window index 0 (in particular we have to avoid a match 1669 * of the string with itself at the start of the input file). 1670 */ 1671 if (s->strategy != Z_HUFFMAN_ONLY) { 1672 s->match_length = longest_match (s, hash_head); 1673 } 1674 /* longest_match() sets match_start */ 1675 } 1676 if (s->match_length >= MIN_MATCH) { 1677 check_match(s, s->strstart, s->match_start, s->match_length); 1678 1679 bflush = _tr_tally(s, s->strstart - s->match_start, 1680 s->match_length - MIN_MATCH); 1681 1682 s->lookahead -= s->match_length; 1683 1684 /* Insert new strings in the hash table only if the match length 1685 * is not too large. This saves time but degrades compression. 1686 */ 1687 if (s->match_length <= s->max_insert_length && 1688 s->lookahead >= MIN_MATCH) { 1689 s->match_length--; /* string at strstart already in hash table */ 1690 do { 1691 s->strstart++; 1692 INSERT_STRING(s, s->strstart, hash_head); 1693 /* strstart never exceeds WSIZE-MAX_MATCH, so there are 1694 * always MIN_MATCH bytes ahead. 1695 */ 1696 } while (--s->match_length != 0); 1697 s->strstart++; 1698 } else { 1699 s->strstart += s->match_length; 1700 s->match_length = 0; 1701 s->ins_h = s->window[s->strstart]; 1702 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]); 1703#if MIN_MATCH != 3 1704 Call UPDATE_HASH() MIN_MATCH-3 more times 1705#endif 1706 /* If lookahead < MIN_MATCH, ins_h is garbage, but it does not 1707 * matter since it will be recomputed at next deflate call. 1708 */ 1709 } 1710 } else { 1711 /* No match, output a literal byte */ 1712 Tracevv((stderr,"%c", s->window[s->strstart])); 1713 bflush = _tr_tally (s, 0, s->window[s->strstart]); 1714 s->lookahead--; 1715 s->strstart++; 1716 } 1717 if (bflush) FLUSH_BLOCK(s, 0); 1718 } 1719 FLUSH_BLOCK(s, flush == Z_FINISH); 1720 return flush == Z_FINISH ? finish_done : block_done; 1721} 1722 1723/* =========================================================================== 1724 * Same as above, but achieves better compression. We use a lazy 1725 * evaluation for matches: a match is finally adopted only if there is 1726 * no better match at the next window position. 1727 */ 1728local block_state deflate_slow(s, flush) 1729 deflate_state *s; 1730 int flush; 1731{ 1732 IPos hash_head = NIL; /* head of hash chain */ 1733 int bflush; /* set if current block must be flushed */ 1734 1735 /* Process the input block. */ 1736 for (;;) { 1737 /* Make sure that we always have enough lookahead, except 1738 * at the end of the input file. We need MAX_MATCH bytes 1739 * for the next match, plus MIN_MATCH bytes to insert the 1740 * string following the next match. 1741 */ 1742 if (s->lookahead < MIN_LOOKAHEAD) { 1743 fill_window(s); 1744 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) { 1745 return need_more; 1746 } 1747 if (s->lookahead == 0) break; /* flush the current block */ 1748 } 1749 1750 /* Insert the string window[strstart .. strstart+2] in the 1751 * dictionary, and set hash_head to the head of the hash chain: 1752 */ 1753 if (s->lookahead >= MIN_MATCH) { 1754 INSERT_STRING(s, s->strstart, hash_head); 1755 } 1756 1757 /* Find the longest match, discarding those <= prev_length. 1758 */ 1759 s->prev_length = s->match_length, s->prev_match = s->match_start; 1760 s->match_length = MIN_MATCH-1; 1761 1762 if (hash_head != NIL && s->prev_length < s->max_lazy_match && 1763 s->strstart - hash_head <= MAX_DIST(s)) { 1764 /* To simplify the code, we prevent matches with the string 1765 * of window index 0 (in particular we have to avoid a match 1766 * of the string with itself at the start of the input file). 1767 */ 1768 if (s->strategy != Z_HUFFMAN_ONLY) { 1769 s->match_length = longest_match (s, hash_head); 1770 } 1771 /* longest_match() sets match_start */ 1772 1773 if (s->match_length <= 5 && (s->strategy == Z_FILTERED || 1774 (s->match_length == MIN_MATCH && 1775 s->strstart - s->match_start > TOO_FAR))) { 1776 1777 /* If prev_match is also MIN_MATCH, match_start is garbage 1778 * but we will ignore the current match anyway. 1779 */ 1780 s->match_length = MIN_MATCH-1; 1781 } 1782 } 1783 /* If there was a match at the previous step and the current 1784 * match is not better, output the previous match: 1785 */ 1786 if (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) { 1787 uInt max_insert = s->strstart + s->lookahead - MIN_MATCH; 1788 /* Do not insert strings in hash table beyond this. */ 1789 1790 check_match(s, s->strstart-1, s->prev_match, s->prev_length); 1791 1792 bflush = _tr_tally(s, s->strstart -1 - s->prev_match, 1793 s->prev_length - MIN_MATCH); 1794 1795 /* Insert in hash table all strings up to the end of the match. 1796 * strstart-1 and strstart are already inserted. If there is not 1797 * enough lookahead, the last two strings are not inserted in 1798 * the hash table. 1799 */ 1800 s->lookahead -= s->prev_length-1; 1801 s->prev_length -= 2; 1802 do { 1803 if (++s->strstart <= max_insert) { 1804 INSERT_STRING(s, s->strstart, hash_head); 1805 } 1806 } while (--s->prev_length != 0); 1807 s->match_available = 0; 1808 s->match_length = MIN_MATCH-1; 1809 s->strstart++; 1810 1811 if (bflush) FLUSH_BLOCK(s, 0); 1812 1813 } else if (s->match_available) { 1814 /* If there was no match at the previous position, output a 1815 * single literal. If there was a match but the current match 1816 * is longer, truncate the previous match to a single literal. 1817 */ 1818 Tracevv((stderr,"%c", s->window[s->strstart-1])); 1819 if (_tr_tally (s, 0, s->window[s->strstart-1])) { 1820 FLUSH_BLOCK_ONLY(s, 0); 1821 } 1822 s->strstart++; 1823 s->lookahead--; 1824 if (s->strm->avail_out == 0) return need_more; 1825 } else { 1826 /* There is no previous match to compare with, wait for 1827 * the next step to decide. 1828 */ 1829 s->match_available = 1; 1830 s->strstart++; 1831 s->lookahead--; 1832 } 1833 } 1834 Assert (flush != Z_NO_FLUSH, "no flush?"); 1835 if (s->match_available) { 1836 Tracevv((stderr,"%c", s->window[s->strstart-1])); 1837 _tr_tally (s, 0, s->window[s->strstart-1]); 1838 s->match_available = 0; 1839 } 1840 FLUSH_BLOCK(s, flush == Z_FINISH); 1841 return flush == Z_FINISH ? finish_done : block_done; 1842} 1843/* --- deflate.c */ 1844 1845/* +++ trees.c */ 1846/* trees.c -- output deflated data using Huffman coding 1847 * Copyright (C) 1995-1996 Jean-loup Gailly 1848 * For conditions of distribution and use, see copyright notice in zlib.h 1849 */ 1850 1851/* 1852 * ALGORITHM 1853 * 1854 * The "deflation" process uses several Huffman trees. The more 1855 * common source values are represented by shorter bit sequences. 1856 * 1857 * Each code tree is stored in a compressed form which is itself 1858 * a Huffman encoding of the lengths of all the code strings (in 1859 * ascending order by source values). The actual code strings are 1860 * reconstructed from the lengths in the inflate process, as described 1861 * in the deflate specification. 1862 * 1863 * REFERENCES 1864 * 1865 * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification". 1866 * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc 1867 * 1868 * Storer, James A. 1869 * Data Compression: Methods and Theory, pp. 49-50. 1870 * Computer Science Press, 1988. ISBN 0-7167-8156-5. 1871 * 1872 * Sedgewick, R. 1873 * Algorithms, p290. 1874 * Addison-Wesley, 1983. ISBN 0-201-06672-6. 1875 */ 1876 1877/* From: trees.c,v 1.11 1996/07/24 13:41:06 me Exp $ */ 1878 1879/* #include "deflate.h" */ 1880 1881#ifdef DEBUG_ZLIB 1882# include <ctype.h> 1883#endif 1884 1885/* =========================================================================== 1886 * Constants 1887 */ 1888 1889#define MAX_BL_BITS 7 1890/* Bit length codes must not exceed MAX_BL_BITS bits */ 1891 1892#define END_BLOCK 256 1893/* end of block literal code */ 1894 1895#define REP_3_6 16 1896/* repeat previous bit length 3-6 times (2 bits of repeat count) */ 1897 1898#define REPZ_3_10 17 1899/* repeat a zero length 3-10 times (3 bits of repeat count) */ 1900 1901#define REPZ_11_138 18 1902/* repeat a zero length 11-138 times (7 bits of repeat count) */ 1903 1904local int extra_lbits[LENGTH_CODES] /* extra bits for each length code */ 1905 = {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}; 1906 1907local int extra_dbits[D_CODES] /* extra bits for each distance code */ 1908 = {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}; 1909 1910local int extra_blbits[BL_CODES]/* extra bits for each bit length code */ 1911 = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7}; 1912 1913local uch bl_order[BL_CODES] 1914 = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15}; 1915/* The lengths of the bit length codes are sent in order of decreasing 1916 * probability, to avoid transmitting the lengths for unused bit length codes. 1917 */ 1918 1919#define Buf_size (8 * 2*sizeof(char)) 1920/* Number of bits used within bi_buf. (bi_buf might be implemented on 1921 * more than 16 bits on some systems.) 1922 */ 1923 1924/* =========================================================================== 1925 * Local data. These are initialized only once. 1926 */ 1927 1928local ct_data static_ltree[L_CODES+2]; 1929/* The static literal tree. Since the bit lengths are imposed, there is no 1930 * need for the L_CODES extra codes used during heap construction. However 1931 * The codes 286 and 287 are needed to build a canonical tree (see _tr_init 1932 * below). 1933 */ 1934 1935local ct_data static_dtree[D_CODES]; 1936/* The static distance tree. (Actually a trivial tree since all codes use 1937 * 5 bits.) 1938 */ 1939 1940local uch dist_code[512]; 1941/* distance codes. The first 256 values correspond to the distances 1942 * 3 .. 258, the last 256 values correspond to the top 8 bits of 1943 * the 15 bit distances. 1944 */ 1945 1946local uch length_code[MAX_MATCH-MIN_MATCH+1]; 1947/* length code for each normalized match length (0 == MIN_MATCH) */ 1948 1949local int base_length[LENGTH_CODES]; 1950/* First normalized length for each code (0 = MIN_MATCH) */ 1951 1952local int base_dist[D_CODES]; 1953/* First normalized distance for each code (0 = distance of 1) */ 1954 1955struct static_tree_desc_s { 1956 ct_data *static_tree; /* static tree or NULL */ 1957 intf *extra_bits; /* extra bits for each code or NULL */ 1958 int extra_base; /* base index for extra_bits */ 1959 int elems; /* max number of elements in the tree */ 1960 int max_length; /* max bit length for the codes */ 1961}; 1962 1963local static_tree_desc static_l_desc = 1964{static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS}; 1965 1966local static_tree_desc static_d_desc = 1967{static_dtree, extra_dbits, 0, D_CODES, MAX_BITS}; 1968 1969local static_tree_desc static_bl_desc = 1970{(ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS}; 1971 1972/* =========================================================================== 1973 * Local (static) routines in this file. 1974 */ 1975 1976local void tr_static_init OF((void)); 1977local void init_block OF((deflate_state *s)); 1978local void pqdownheap OF((deflate_state *s, ct_data *tree, int k)); 1979local void gen_bitlen OF((deflate_state *s, tree_desc *desc)); 1980local void gen_codes OF((ct_data *tree, int max_code, ushf *bl_count)); 1981local void build_tree OF((deflate_state *s, tree_desc *desc)); 1982local void scan_tree OF((deflate_state *s, ct_data *tree, int max_code)); 1983local void send_tree OF((deflate_state *s, ct_data *tree, int max_code)); 1984local int build_bl_tree OF((deflate_state *s)); 1985local void send_all_trees OF((deflate_state *s, int lcodes, int dcodes, 1986 int blcodes)); 1987local void compress_block OF((deflate_state *s, ct_data *ltree, 1988 ct_data *dtree)); 1989local void set_data_type OF((deflate_state *s)); 1990local unsigned bi_reverse OF((unsigned value, int length)); 1991local void bi_windup OF((deflate_state *s)); 1992local void bi_flush OF((deflate_state *s)); 1993local void copy_block OF((deflate_state *s, charf *buf, unsigned len, 1994 int header)); 1995 1996#ifndef DEBUG_ZLIB 1997# define send_code(s, c, tree) send_bits(s, tree[(c)].Code, tree[(c)].Len) 1998 /* Send a code of the given tree. c and tree must not have side effects */ 1999 2000#else /* DEBUG_ZLIB */ 2001# define send_code(s, c, tree) \ 2002 { if (verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \ 2003 send_bits(s, tree[c].Code, tree[c].Len); } 2004#endif 2005 2006#define d_code(dist) \ 2007 ((dist) < 256 ? dist_code[dist] : dist_code[256+((dist)>>7)]) 2008/* Mapping from a distance to a distance code. dist is the distance - 1 and 2009 * must not have side effects. dist_code[256] and dist_code[257] are never 2010 * used. 2011 */ 2012 2013/* =========================================================================== 2014 * Output a short LSB first on the stream. 2015 * IN assertion: there is enough room in pendingBuf. 2016 */ 2017#define put_short(s, w) { \ 2018 put_byte(s, (uch)((w) & 0xff)); \ 2019 put_byte(s, (uch)((ush)(w) >> 8)); \ 2020} 2021 2022/* =========================================================================== 2023 * Send a value on a given number of bits. 2024 * IN assertion: length <= 16 and value fits in length bits. 2025 */ 2026#ifdef DEBUG_ZLIB 2027local void send_bits OF((deflate_state *s, int value, int length)); 2028 2029local void send_bits(s, value, length) 2030 deflate_state *s; 2031 int value; /* value to send */ 2032 int length; /* number of bits */ 2033{ 2034 Tracevv((stderr," l %2d v %4x ", length, value)); 2035 Assert(length > 0 && length <= 15, "invalid length"); 2036 s->bits_sent += (ulg)length; 2037 2038 /* If not enough room in bi_buf, use (valid) bits from bi_buf and 2039 * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid)) 2040 * unused bits in value. 2041 */ 2042 if (s->bi_valid > (int)Buf_size - length) { 2043 s->bi_buf |= (value << s->bi_valid); 2044 put_short(s, s->bi_buf); 2045 s->bi_buf = (ush)value >> (Buf_size - s->bi_valid); 2046 s->bi_valid += length - Buf_size; 2047 } else { 2048 s->bi_buf |= value << s->bi_valid; 2049 s->bi_valid += length; 2050 } 2051} 2052#else /* !DEBUG_ZLIB */ 2053 2054#define send_bits(s, value, length) \ 2055{ int len = (length);\ 2056 if ((s)->bi_valid > (int)Buf_size - len) {\ 2057 int val = (value);\ 2058 (s)->bi_buf |= (val << (s)->bi_valid);\ 2059 put_short((s), (s)->bi_buf);\ 2060 (s)->bi_buf = (ush)val >> (Buf_size - (s)->bi_valid);\ 2061 (s)->bi_valid += len - Buf_size;\ 2062 } else {\ 2063 (s)->bi_buf |= (value) << (s)->bi_valid;\ 2064 (s)->bi_valid += len;\ 2065 }\ 2066} 2067#endif /* DEBUG_ZLIB */ 2068 2069/* the arguments must not have side effects */ 2070 2071/* =========================================================================== 2072 * Initialize the various 'constant' tables. In a multi-threaded environment, 2073 * this function may be called by two threads concurrently, but this is 2074 * harmless since both invocations do exactly the same thing. 2075 */ 2076local void tr_static_init() 2077{ 2078 static int static_init_done = 0; 2079 int n; /* iterates over tree elements */ 2080 int bits; /* bit counter */ 2081 int length; /* length value */ 2082 int code; /* code value */ 2083 int dist; /* distance index */ 2084 ush bl_count[MAX_BITS+1]; 2085 /* number of codes at each bit length for an optimal tree */ 2086 2087 if (static_init_done) return; 2088 2089 /* Initialize the mapping length (0..255) -> length code (0..28) */ 2090 length = 0; 2091 for (code = 0; code < LENGTH_CODES-1; code++) { 2092 base_length[code] = length; 2093 for (n = 0; n < (1<<extra_lbits[code]); n++) { 2094 length_code[length++] = (uch)code; 2095 } 2096 } 2097 Assert (length == 256, "tr_static_init: length != 256"); 2098 /* Note that the length 255 (match length 258) can be represented 2099 * in two different ways: code 284 + 5 bits or code 285, so we 2100 * overwrite length_code[255] to use the best encoding: 2101 */ 2102 length_code[length-1] = (uch)code; 2103 2104 /* Initialize the mapping dist (0..32K) -> dist code (0..29) */ 2105 dist = 0; 2106 for (code = 0 ; code < 16; code++) { 2107 base_dist[code] = dist; 2108 for (n = 0; n < (1<<extra_dbits[code]); n++) { 2109 dist_code[dist++] = (uch)code; 2110 } 2111 } 2112 Assert (dist == 256, "tr_static_init: dist != 256"); 2113 dist >>= 7; /* from now on, all distances are divided by 128 */ 2114 for ( ; code < D_CODES; code++) { 2115 base_dist[code] = dist << 7; 2116 for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) { 2117 dist_code[256 + dist++] = (uch)code; 2118 } 2119 } 2120 Assert (dist == 256, "tr_static_init: 256+dist != 512"); 2121 2122 /* Construct the codes of the static literal tree */ 2123 for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0; 2124 n = 0; 2125 while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++; 2126 while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++; 2127 while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++; 2128 while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++; 2129 /* Codes 286 and 287 do not exist, but we must include them in the 2130 * tree construction to get a canonical Huffman tree (longest code 2131 * all ones) 2132 */ 2133 gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count); 2134 2135 /* The static distance tree is trivial: */ 2136 for (n = 0; n < D_CODES; n++) { 2137 static_dtree[n].Len = 5; 2138 static_dtree[n].Code = bi_reverse((unsigned)n, 5); 2139 } 2140 static_init_done = 1; 2141} 2142 2143/* =========================================================================== 2144 * Initialize the tree data structures for a new zlib stream. 2145 */ 2146void _tr_init(s) 2147 deflate_state *s; 2148{ 2149 tr_static_init(); 2150 2151 s->compressed_len = 0L; 2152 2153 s->l_desc.dyn_tree = s->dyn_ltree; 2154 s->l_desc.stat_desc = &static_l_desc; 2155 2156 s->d_desc.dyn_tree = s->dyn_dtree; 2157 s->d_desc.stat_desc = &static_d_desc; 2158 2159 s->bl_desc.dyn_tree = s->bl_tree; 2160 s->bl_desc.stat_desc = &static_bl_desc; 2161 2162 s->bi_buf = 0; 2163 s->bi_valid = 0; 2164 s->last_eob_len = 8; /* enough lookahead for inflate */ 2165#ifdef DEBUG_ZLIB 2166 s->bits_sent = 0L; 2167#endif 2168 2169 /* Initialize the first block of the first file: */ 2170 init_block(s); 2171} 2172 2173/* =========================================================================== 2174 * Initialize a new block. 2175 */ 2176local void init_block(s) 2177 deflate_state *s; 2178{ 2179 int n; /* iterates over tree elements */ 2180 2181 /* Initialize the trees. */ 2182 for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0; 2183 for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0; 2184 for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0; 2185 2186 s->dyn_ltree[END_BLOCK].Freq = 1; 2187 s->opt_len = s->static_len = 0L; 2188 s->last_lit = s->matches = 0; 2189} 2190 2191#define SMALLEST 1 2192/* Index within the heap array of least frequent node in the Huffman tree */ 2193 2194 2195/* =========================================================================== 2196 * Remove the smallest element from the heap and recreate the heap with 2197 * one less element. Updates heap and heap_len. 2198 */ 2199#define pqremove(s, tree, top) \ 2200{\ 2201 top = s->heap[SMALLEST]; \ 2202 s->heap[SMALLEST] = s->heap[s->heap_len--]; \ 2203 pqdownheap(s, tree, SMALLEST); \ 2204} 2205 2206/* =========================================================================== 2207 * Compares to subtrees, using the tree depth as tie breaker when 2208 * the subtrees have equal frequency. This minimizes the worst case length. 2209 */ 2210#define smaller(tree, n, m, depth) \ 2211 (tree[n].Freq < tree[m].Freq || \ 2212 (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m])) 2213 2214/* =========================================================================== 2215 * Restore the heap property by moving down the tree starting at node k, 2216 * exchanging a node with the smallest of its two sons if necessary, stopping 2217 * when the heap property is re-established (each father smaller than its 2218 * two sons). 2219 */ 2220local void pqdownheap(s, tree, k) 2221 deflate_state *s; 2222 ct_data *tree; /* the tree to restore */ 2223 int k; /* node to move down */ 2224{ 2225 int v = s->heap[k]; 2226 int j = k << 1; /* left son of k */ 2227 while (j <= s->heap_len) { 2228 /* Set j to the smallest of the two sons: */ 2229 if (j < s->heap_len && 2230 smaller(tree, s->heap[j+1], s->heap[j], s->depth)) { 2231 j++; 2232 } 2233 /* Exit if v is smaller than both sons */ 2234 if (smaller(tree, v, s->heap[j], s->depth)) break; 2235 2236 /* Exchange v with the smallest son */ 2237 s->heap[k] = s->heap[j]; k = j; 2238 2239 /* And continue down the tree, setting j to the left son of k */ 2240 j <<= 1; 2241 } 2242 s->heap[k] = v; 2243} 2244 2245/* =========================================================================== 2246 * Compute the optimal bit lengths for a tree and update the total bit length 2247 * for the current block. 2248 * IN assertion: the fields freq and dad are set, heap[heap_max] and 2249 * above are the tree nodes sorted by increasing frequency. 2250 * OUT assertions: the field len is set to the optimal bit length, the 2251 * array bl_count contains the frequencies for each bit length. 2252 * The length opt_len is updated; static_len is also updated if stree is 2253 * not null. 2254 */ 2255local void gen_bitlen(s, desc) 2256 deflate_state *s; 2257 tree_desc *desc; /* the tree descriptor */ 2258{ 2259 ct_data *tree = desc->dyn_tree; 2260 int max_code = desc->max_code; 2261 ct_data *stree = desc->stat_desc->static_tree; 2262 intf *extra = desc->stat_desc->extra_bits; 2263 int base = desc->stat_desc->extra_base; 2264 int max_length = desc->stat_desc->max_length; 2265 int h; /* heap index */ 2266 int n, m; /* iterate over the tree elements */ 2267 int bits; /* bit length */ 2268 int xbits; /* extra bits */ 2269 ush f; /* frequency */ 2270 int overflow = 0; /* number of elements with bit length too large */ 2271 2272 for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0; 2273 2274 /* In a first pass, compute the optimal bit lengths (which may 2275 * overflow in the case of the bit length tree). 2276 */ 2277 tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */ 2278 2279 for (h = s->heap_max+1; h < HEAP_SIZE; h++) { 2280 n = s->heap[h]; 2281 bits = tree[tree[n].Dad].Len + 1; 2282 if (bits > max_length) bits = max_length, overflow++; 2283 tree[n].Len = (ush)bits; 2284 /* We overwrite tree[n].Dad which is no longer needed */ 2285 2286 if (n > max_code) continue; /* not a leaf node */ 2287 2288 s->bl_count[bits]++; 2289 xbits = 0; 2290 if (n >= base) xbits = extra[n-base]; 2291 f = tree[n].Freq; 2292 s->opt_len += (ulg)f * (bits + xbits); 2293 if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits); 2294 } 2295 if (overflow == 0) return; 2296 2297 Trace((stderr,"\nbit length overflow\n")); 2298 /* This happens for example on obj2 and pic of the Calgary corpus */ 2299 2300 /* Find the first bit length which could increase: */ 2301 do { 2302 bits = max_length-1; 2303 while (s->bl_count[bits] == 0) bits--; 2304 s->bl_count[bits]--; /* move one leaf down the tree */ 2305 s->bl_count[bits+1] += 2; /* move one overflow item as its brother */ 2306 s->bl_count[max_length]--; 2307 /* The brother of the overflow item also moves one step up, 2308 * but this does not affect bl_count[max_length] 2309 */ 2310 overflow -= 2; 2311 } while (overflow > 0); 2312 2313 /* Now recompute all bit lengths, scanning in increasing frequency. 2314 * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all 2315 * lengths instead of fixing only the wrong ones. This idea is taken 2316 * from 'ar' written by Haruhiko Okumura.) 2317 */ 2318 for (bits = max_length; bits != 0; bits--) { 2319 n = s->bl_count[bits]; 2320 while (n != 0) { 2321 m = s->heap[--h]; 2322 if (m > max_code) continue; 2323 if (tree[m].Len != (unsigned) bits) { 2324 Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits)); 2325 s->opt_len += ((long)bits - (long)tree[m].Len) 2326 *(long)tree[m].Freq; 2327 tree[m].Len = (ush)bits; 2328 } 2329 n--; 2330 } 2331 } 2332} 2333 2334/* =========================================================================== 2335 * Generate the codes for a given tree and bit counts (which need not be 2336 * optimal). 2337 * IN assertion: the array bl_count contains the bit length statistics for 2338 * the given tree and the field len is set for all tree elements. 2339 * OUT assertion: the field code is set for all tree elements of non 2340 * zero code length. 2341 */ 2342local void gen_codes (tree, max_code, bl_count) 2343 ct_data *tree; /* the tree to decorate */ 2344 int max_code; /* largest code with non zero frequency */ 2345 ushf *bl_count; /* number of codes at each bit length */ 2346{ 2347 ush next_code[MAX_BITS+1]; /* next code value for each bit length */ 2348 ush code = 0; /* running code value */ 2349 int bits; /* bit index */ 2350 int n; /* code index */ 2351 2352 /* The distribution counts are first used to generate the code values 2353 * without bit reversal. 2354 */ 2355 for (bits = 1; bits <= MAX_BITS; bits++) { 2356 next_code[bits] = code = (code + bl_count[bits-1]) << 1; 2357 } 2358 /* Check that the bit counts in bl_count are consistent. The last code 2359 * must be all ones. 2360 */ 2361 Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1, 2362 "inconsistent bit counts"); 2363 Tracev((stderr,"\ngen_codes: max_code %d ", max_code)); 2364 2365 for (n = 0; n <= max_code; n++) { 2366 int len = tree[n].Len; 2367 if (len == 0) continue; 2368 /* Now reverse the bits */ 2369 tree[n].Code = bi_reverse(next_code[len]++, len); 2370 2371 Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ", 2372 n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1)); 2373 } 2374} 2375 2376/* =========================================================================== 2377 * Construct one Huffman tree and assigns the code bit strings and lengths. 2378 * Update the total bit length for the current block. 2379 * IN assertion: the field freq is set for all tree elements. 2380 * OUT assertions: the fields len and code are set to the optimal bit length 2381 * and corresponding code. The length opt_len is updated; static_len is 2382 * also updated if stree is not null. The field max_code is set. 2383 */ 2384local void build_tree(s, desc) 2385 deflate_state *s; 2386 tree_desc *desc; /* the tree descriptor */ 2387{ 2388 ct_data *tree = desc->dyn_tree; 2389 ct_data *stree = desc->stat_desc->static_tree; 2390 int elems = desc->stat_desc->elems; 2391 int n, m; /* iterate over heap elements */ 2392 int max_code = -1; /* largest code with non zero frequency */ 2393 int node; /* new node being created */ 2394 2395 /* Construct the initial heap, with least frequent element in 2396 * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1]. 2397 * heap[0] is not used. 2398 */ 2399 s->heap_len = 0, s->heap_max = HEAP_SIZE; 2400 2401 for (n = 0; n < elems; n++) { 2402 if (tree[n].Freq != 0) { 2403 s->heap[++(s->heap_len)] = max_code = n; 2404 s->depth[n] = 0; 2405 } else { 2406 tree[n].Len = 0; 2407 } 2408 } 2409 2410 /* The pkzip format requires that at least one distance code exists, 2411 * and that at least one bit should be sent even if there is only one 2412 * possible code. So to avoid special checks later on we force at least 2413 * two codes of non zero frequency. 2414 */ 2415 while (s->heap_len < 2) { 2416 node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0); 2417 tree[node].Freq = 1; 2418 s->depth[node] = 0; 2419 s->opt_len--; if (stree) s->static_len -= stree[node].Len; 2420 /* node is 0 or 1 so it does not have extra bits */ 2421 } 2422 desc->max_code = max_code; 2423 2424 /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree, 2425 * establish sub-heaps of increasing lengths: 2426 */ 2427 for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n); 2428 2429 /* Construct the Huffman tree by repeatedly combining the least two 2430 * frequent nodes. 2431 */ 2432 node = elems; /* next internal node of the tree */ 2433 do { 2434 pqremove(s, tree, n); /* n = node of least frequency */ 2435 m = s->heap[SMALLEST]; /* m = node of next least frequency */ 2436 2437 s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */ 2438 s->heap[--(s->heap_max)] = m; 2439 2440 /* Create a new node father of n and m */ 2441 tree[node].Freq = tree[n].Freq + tree[m].Freq; 2442 s->depth[node] = (uch) (MAX(s->depth[n], s->depth[m]) + 1); 2443 tree[n].Dad = tree[m].Dad = (ush)node; 2444#ifdef DUMP_BL_TREE 2445 if (tree == s->bl_tree) { 2446 fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)", 2447 node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq); 2448 } 2449#endif 2450 /* and insert the new node in the heap */ 2451 s->heap[SMALLEST] = node++; 2452 pqdownheap(s, tree, SMALLEST); 2453 2454 } while (s->heap_len >= 2); 2455 2456 s->heap[--(s->heap_max)] = s->heap[SMALLEST]; 2457 2458 /* At this point, the fields freq and dad are set. We can now 2459 * generate the bit lengths. 2460 */ 2461 gen_bitlen(s, (tree_desc *)desc); 2462 2463 /* The field len is now set, we can generate the bit codes */ 2464 gen_codes ((ct_data *)tree, max_code, s->bl_count); 2465} 2466 2467/* =========================================================================== 2468 * Scan a literal or distance tree to determine the frequencies of the codes 2469 * in the bit length tree. 2470 */ 2471local void scan_tree (s, tree, max_code) 2472 deflate_state *s; 2473 ct_data *tree; /* the tree to be scanned */ 2474 int max_code; /* and its largest code of non zero frequency */ 2475{ 2476 int n; /* iterates over all tree elements */ 2477 int prevlen = -1; /* last emitted length */ 2478 int curlen; /* length of current code */ 2479 int nextlen = tree[0].Len; /* length of next code */ 2480 int count = 0; /* repeat count of the current code */ 2481 int max_count = 7; /* max repeat count */ 2482 int min_count = 4; /* min repeat count */ 2483 2484 if (nextlen == 0) max_count = 138, min_count = 3; 2485 tree[max_code+1].Len = (ush)0xffff; /* guard */ 2486 2487 for (n = 0; n <= max_code; n++) { 2488 curlen = nextlen; nextlen = tree[n+1].Len; 2489 if (++count < max_count && curlen == nextlen) { 2490 continue; 2491 } else if (count < min_count) { 2492 s->bl_tree[curlen].Freq += count; 2493 } else if (curlen != 0) { 2494 if (curlen != prevlen) s->bl_tree[curlen].Freq++; 2495 s->bl_tree[REP_3_6].Freq++; 2496 } else if (count <= 10) { 2497 s->bl_tree[REPZ_3_10].Freq++; 2498 } else { 2499 s->bl_tree[REPZ_11_138].Freq++; 2500 } 2501 count = 0; prevlen = curlen; 2502 if (nextlen == 0) { 2503 max_count = 138, min_count = 3; 2504 } else if (curlen == nextlen) { 2505 max_count = 6, min_count = 3; 2506 } else { 2507 max_count = 7, min_count = 4; 2508 } 2509 } 2510} 2511 2512/* =========================================================================== 2513 * Send a literal or distance tree in compressed form, using the codes in 2514 * bl_tree. 2515 */ 2516local void send_tree (s, tree, max_code) 2517 deflate_state *s; 2518 ct_data *tree; /* the tree to be scanned */ 2519 int max_code; /* and its largest code of non zero frequency */ 2520{ 2521 int n; /* iterates over all tree elements */ 2522 int prevlen = -1; /* last emitted length */ 2523 int curlen; /* length of current code */ 2524 int nextlen = tree[0].Len; /* length of next code */ 2525 int count = 0; /* repeat count of the current code */ 2526 int max_count = 7; /* max repeat count */ 2527 int min_count = 4; /* min repeat count */ 2528 2529 /* tree[max_code+1].Len = -1; */ /* guard already set */ 2530 if (nextlen == 0) max_count = 138, min_count = 3; 2531 2532 for (n = 0; n <= max_code; n++) { 2533 curlen = nextlen; nextlen = tree[n+1].Len; 2534 if (++count < max_count && curlen == nextlen) { 2535 continue; 2536 } else if (count < min_count) { 2537 do { send_code(s, curlen, s->bl_tree); } while (--count != 0); 2538 2539 } else if (curlen != 0) { 2540 if (curlen != prevlen) { 2541 send_code(s, curlen, s->bl_tree); count--; 2542 } 2543 Assert(count >= 3 && count <= 6, " 3_6?"); 2544 send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2); 2545 2546 } else if (count <= 10) { 2547 send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3); 2548 2549 } else { 2550 send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7); 2551 } 2552 count = 0; prevlen = curlen; 2553 if (nextlen == 0) { 2554 max_count = 138, min_count = 3; 2555 } else if (curlen == nextlen) { 2556 max_count = 6, min_count = 3; 2557 } else { 2558 max_count = 7, min_count = 4; 2559 } 2560 } 2561} 2562 2563/* =========================================================================== 2564 * Construct the Huffman tree for the bit lengths and return the index in 2565 * bl_order of the last bit length code to send. 2566 */ 2567local int build_bl_tree(s) 2568 deflate_state *s; 2569{ 2570 int max_blindex; /* index of last bit length code of non zero freq */ 2571 2572 /* Determine the bit length frequencies for literal and distance trees */ 2573 scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code); 2574 scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code); 2575 2576 /* Build the bit length tree: */ 2577 build_tree(s, (tree_desc *)(&(s->bl_desc))); 2578 /* opt_len now includes the length of the tree representations, except 2579 * the lengths of the bit lengths codes and the 5+5+4 bits for the counts. 2580 */ 2581 2582 /* Determine the number of bit length codes to send. The pkzip format 2583 * requires that at least 4 bit length codes be sent. (appnote.txt says 2584 * 3 but the actual value used is 4.) 2585 */ 2586 for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) { 2587 if (s->bl_tree[bl_order[max_blindex]].Len != 0) break; 2588 } 2589 /* Update opt_len to include the bit length tree and counts */ 2590 s->opt_len += 3*(max_blindex+1) + 5+5+4; 2591 Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld", 2592 s->opt_len, s->static_len)); 2593 2594 return max_blindex; 2595} 2596 2597/* =========================================================================== 2598 * Send the header for a block using dynamic Huffman trees: the counts, the 2599 * lengths of the bit length codes, the literal tree and the distance tree. 2600 * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4. 2601 */ 2602local void send_all_trees(s, lcodes, dcodes, blcodes) 2603 deflate_state *s; 2604 int lcodes, dcodes, blcodes; /* number of codes for each tree */ 2605{ 2606 int rank; /* index in bl_order */ 2607 2608 Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes"); 2609 Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES, 2610 "too many codes"); 2611 Tracev((stderr, "\nbl counts: ")); 2612 send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */ 2613 send_bits(s, dcodes-1, 5); 2614 send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */ 2615 for (rank = 0; rank < blcodes; rank++) { 2616 Tracev((stderr, "\nbl code %2d ", bl_order[rank])); 2617 send_bits(s, s->bl_tree[bl_order[rank]].Len, 3); 2618 } 2619 Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent)); 2620 2621 send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */ 2622 Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent)); 2623 2624 send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */ 2625 Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent)); 2626} 2627 2628/* =========================================================================== 2629 * Send a stored block 2630 */ 2631void _tr_stored_block(s, buf, stored_len, eof) 2632 deflate_state *s; 2633 charf *buf; /* input block */ 2634 ulg stored_len; /* length of input block */ 2635 int eof; /* true if this is the last block for a file */ 2636{ 2637 send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */ 2638 s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L; 2639 s->compressed_len += (stored_len + 4) << 3; 2640 2641 copy_block(s, buf, (unsigned)stored_len, 1); /* with header */ 2642} 2643 2644/* Send just the `stored block' type code without any length bytes or data. 2645 */ 2646void _tr_stored_type_only(s) 2647 deflate_state *s; 2648{ 2649 send_bits(s, (STORED_BLOCK << 1), 3); 2650 bi_windup(s); 2651 s->compressed_len = (s->compressed_len + 3) & ~7L; 2652} 2653 2654 2655/* =========================================================================== 2656 * Send one empty static block to give enough lookahead for inflate. 2657 * This takes 10 bits, of which 7 may remain in the bit buffer. 2658 * The current inflate code requires 9 bits of lookahead. If the 2659 * last two codes for the previous block (real code plus EOB) were coded 2660 * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode 2661 * the last real code. In this case we send two empty static blocks instead 2662 * of one. (There are no problems if the previous block is stored or fixed.) 2663 * To simplify the code, we assume the worst case of last real code encoded 2664 * on one bit only. 2665 */ 2666void _tr_align(s) 2667 deflate_state *s; 2668{ 2669 send_bits(s, STATIC_TREES<<1, 3); 2670 send_code(s, END_BLOCK, static_ltree); 2671 s->compressed_len += 10L; /* 3 for block type, 7 for EOB */ 2672 bi_flush(s); 2673 /* Of the 10 bits for the empty block, we have already sent 2674 * (10 - bi_valid) bits. The lookahead for the last real code (before 2675 * the EOB of the previous block) was thus at least one plus the length 2676 * of the EOB plus what we have just sent of the empty static block. 2677 */ 2678 if (1 + s->last_eob_len + 10 - s->bi_valid < 9) { 2679 send_bits(s, STATIC_TREES<<1, 3); 2680 send_code(s, END_BLOCK, static_ltree); 2681 s->compressed_len += 10L; 2682 bi_flush(s); 2683 } 2684 s->last_eob_len = 7; 2685} 2686 2687/* =========================================================================== 2688 * Determine the best encoding for the current block: dynamic trees, static 2689 * trees or store, and output the encoded block to the zip file. This function 2690 * returns the total compressed length for the file so far. 2691 */ 2692ulg _tr_flush_block(s, buf, stored_len, eof) 2693 deflate_state *s; 2694 charf *buf; /* input block, or NULL if too old */ 2695 ulg stored_len; /* length of input block */ 2696 int eof; /* true if this is the last block for a file */ 2697{ 2698 ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */ 2699 int max_blindex = 0; /* index of last bit length code of non zero freq */ 2700 2701 /* Build the Huffman trees unless a stored block is forced */ 2702 if (s->level > 0) { 2703 2704 /* Check if the file is ascii or binary */ 2705 if (s->data_type == Z_UNKNOWN) set_data_type(s); 2706 2707 /* Construct the literal and distance trees */ 2708 build_tree(s, (tree_desc *)(&(s->l_desc))); 2709 Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len, 2710 s->static_len)); 2711 2712 build_tree(s, (tree_desc *)(&(s->d_desc))); 2713 Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len, 2714 s->static_len)); 2715 /* At this point, opt_len and static_len are the total bit lengths of 2716 * the compressed block data, excluding the tree representations. 2717 */ 2718 2719 /* Build the bit length tree for the above two trees, and get the index 2720 * in bl_order of the last bit length code to send. 2721 */ 2722 max_blindex = build_bl_tree(s); 2723 2724 /* Determine the best encoding. Compute first the block length in bytes*/ 2725 opt_lenb = (s->opt_len+3+7)>>3; 2726 static_lenb = (s->static_len+3+7)>>3; 2727 2728 Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ", 2729 opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len, 2730 s->last_lit)); 2731 2732 if (static_lenb <= opt_lenb) opt_lenb = static_lenb; 2733 2734 } else { 2735 Assert(buf != (char*)0, "lost buf"); 2736 opt_lenb = static_lenb = stored_len + 5; /* force a stored block */ 2737 } 2738 2739 /* If compression failed and this is the first and last block, 2740 * and if the .zip file can be seeked (to rewrite the local header), 2741 * the whole file is transformed into a stored file: 2742 */ 2743#ifdef STORED_FILE_OK 2744# ifdef FORCE_STORED_FILE 2745 if (eof && s->compressed_len == 0L) { /* force stored file */ 2746# else 2747 if (stored_len <= opt_lenb && eof && s->compressed_len==0L && seekable()) { 2748# endif 2749 /* Since LIT_BUFSIZE <= 2*WSIZE, the input data must be there: */ 2750 if (buf == (charf*)0) error ("block vanished"); 2751 2752 copy_block(s, buf, (unsigned)stored_len, 0); /* without header */ 2753 s->compressed_len = stored_len << 3; 2754 s->method = STORED; 2755 } else 2756#endif /* STORED_FILE_OK */ 2757 2758#ifdef FORCE_STORED 2759 if (buf != (char*)0) { /* force stored block */ 2760#else 2761 if (stored_len+4 <= opt_lenb && buf != (char*)0) { 2762 /* 4: two words for the lengths */ 2763#endif 2764 /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE. 2765 * Otherwise we can't have processed more than WSIZE input bytes since 2766 * the last block flush, because compression would have been 2767 * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to 2768 * transform a block into a stored block. 2769 */ 2770 _tr_stored_block(s, buf, stored_len, eof); 2771 2772#ifdef FORCE_STATIC 2773 } else if (static_lenb >= 0) { /* force static trees */ 2774#else 2775 } else if (static_lenb == opt_lenb) { 2776#endif 2777 send_bits(s, (STATIC_TREES<<1)+eof, 3); 2778 compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree); 2779 s->compressed_len += 3 + s->static_len; 2780 } else { 2781 send_bits(s, (DYN_TREES<<1)+eof, 3); 2782 send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1, 2783 max_blindex+1); 2784 compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree); 2785 s->compressed_len += 3 + s->opt_len; 2786 } 2787 Assert (s->compressed_len == s->bits_sent, "bad compressed size"); 2788 init_block(s); 2789 2790 if (eof) { 2791 bi_windup(s); 2792 s->compressed_len += 7; /* align on byte boundary */ 2793 } 2794 Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3, 2795 s->compressed_len-7*eof)); 2796 2797 return s->compressed_len >> 3; 2798} 2799 2800/* =========================================================================== 2801 * Save the match info and tally the frequency counts. Return true if 2802 * the current block must be flushed. 2803 */ 2804int _tr_tally (s, dist, lc) 2805 deflate_state *s; 2806 unsigned dist; /* distance of matched string */ 2807 unsigned lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */ 2808{ 2809 s->d_buf[s->last_lit] = (ush)dist; 2810 s->l_buf[s->last_lit++] = (uch)lc; 2811 if (dist == 0) { 2812 /* lc is the unmatched char */ 2813 s->dyn_ltree[lc].Freq++; 2814 } else { 2815 s->matches++; 2816 /* Here, lc is the match length - MIN_MATCH */ 2817 dist--; /* dist = match distance - 1 */ 2818 Assert((ush)dist < (ush)MAX_DIST(s) && 2819 (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) && 2820 (ush)d_code(dist) < (ush)D_CODES, "_tr_tally: bad match"); 2821 2822 s->dyn_ltree[length_code[lc]+LITERALS+1].Freq++; 2823 s->dyn_dtree[d_code(dist)].Freq++; 2824 } 2825 2826 /* Try to guess if it is profitable to stop the current block here */ 2827 if (s->level > 2 && (s->last_lit & 0xfff) == 0) { 2828 /* Compute an upper bound for the compressed length */ 2829 ulg out_length = (ulg)s->last_lit*8L; 2830 ulg in_length = (ulg)((long)s->strstart - s->block_start); 2831 int dcode; 2832 for (dcode = 0; dcode < D_CODES; dcode++) { 2833 out_length += (ulg)s->dyn_dtree[dcode].Freq * 2834 (5L+extra_dbits[dcode]); 2835 } 2836 out_length >>= 3; 2837 Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ", 2838 s->last_lit, in_length, out_length, 2839 100L - out_length*100L/in_length)); 2840 if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1; 2841 } 2842 return (s->last_lit == s->lit_bufsize-1); 2843 /* We avoid equality with lit_bufsize because of wraparound at 64K 2844 * on 16 bit machines and because stored blocks are restricted to 2845 * 64K-1 bytes. 2846 */ 2847} 2848 2849/* =========================================================================== 2850 * Send the block data compressed using the given Huffman trees 2851 */ 2852local void compress_block(s, ltree, dtree) 2853 deflate_state *s; 2854 ct_data *ltree; /* literal tree */ 2855 ct_data *dtree; /* distance tree */ 2856{ 2857 unsigned dist; /* distance of matched string */ 2858 int lc; /* match length or unmatched char (if dist == 0) */ 2859 unsigned lx = 0; /* running index in l_buf */ 2860 unsigned code; /* the code to send */ 2861 int extra; /* number of extra bits to send */ 2862 2863 if (s->last_lit != 0) do { 2864 dist = s->d_buf[lx]; 2865 lc = s->l_buf[lx++]; 2866 if (dist == 0) { 2867 send_code(s, lc, ltree); /* send a literal byte */ 2868 Tracecv(isgraph(lc), (stderr," '%c' ", lc)); 2869 } else { 2870 /* Here, lc is the match length - MIN_MATCH */ 2871 code = length_code[lc]; 2872 send_code(s, code+LITERALS+1, ltree); /* send the length code */ 2873 extra = extra_lbits[code]; 2874 if (extra != 0) { 2875 lc -= base_length[code]; 2876 send_bits(s, lc, extra); /* send the extra length bits */ 2877 } 2878 dist--; /* dist is now the match distance - 1 */ 2879 code = d_code(dist); 2880 Assert (code < D_CODES, "bad d_code"); 2881 2882 send_code(s, code, dtree); /* send the distance code */ 2883 extra = extra_dbits[code]; 2884 if (extra != 0) { 2885 dist -= base_dist[code]; 2886 send_bits(s, dist, extra); /* send the extra distance bits */ 2887 } 2888 } /* literal or match pair ? */ 2889 2890 /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */ 2891 Assert(s->pending < s->lit_bufsize + 2*lx, "pendingBuf overflow"); 2892 2893 } while (lx < s->last_lit); 2894 2895 send_code(s, END_BLOCK, ltree); 2896 s->last_eob_len = ltree[END_BLOCK].Len; 2897} 2898 2899/* =========================================================================== 2900 * Set the data type to ASCII or BINARY, using a crude approximation: 2901 * binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise. 2902 * IN assertion: the fields freq of dyn_ltree are set and the total of all 2903 * frequencies does not exceed 64K (to fit in an int on 16 bit machines). 2904 */ 2905local void set_data_type(s) 2906 deflate_state *s; 2907{ 2908 int n = 0; 2909 unsigned ascii_freq = 0; 2910 unsigned bin_freq = 0; 2911 while (n < 7) bin_freq += s->dyn_ltree[n++].Freq; 2912 while (n < 128) ascii_freq += s->dyn_ltree[n++].Freq; 2913 while (n < LITERALS) bin_freq += s->dyn_ltree[n++].Freq; 2914 s->data_type = (Byte)(bin_freq > (ascii_freq >> 2) ? Z_BINARY : Z_ASCII); 2915} 2916 2917/* =========================================================================== 2918 * Reverse the first len bits of a code, using straightforward code (a faster 2919 * method would use a table) 2920 * IN assertion: 1 <= len <= 15 2921 */ 2922local unsigned bi_reverse(code, len) 2923 unsigned code; /* the value to invert */ 2924 int len; /* its bit length */ 2925{ 2926 register unsigned res = 0; 2927 do { 2928 res |= code & 1; 2929 code >>= 1, res <<= 1; 2930 } while (--len > 0); 2931 return res >> 1; 2932} 2933 2934/* =========================================================================== 2935 * Flush the bit buffer, keeping at most 7 bits in it. 2936 */ 2937local void bi_flush(s) 2938 deflate_state *s; 2939{ 2940 if (s->bi_valid == 16) { 2941 put_short(s, s->bi_buf); 2942 s->bi_buf = 0; 2943 s->bi_valid = 0; 2944 } else if (s->bi_valid >= 8) { 2945 put_byte(s, (Byte)s->bi_buf); 2946 s->bi_buf >>= 8; 2947 s->bi_valid -= 8; 2948 } 2949} 2950 2951/* =========================================================================== 2952 * Flush the bit buffer and align the output on a byte boundary 2953 */ 2954local void bi_windup(s) 2955 deflate_state *s; 2956{ 2957 if (s->bi_valid > 8) { 2958 put_short(s, s->bi_buf); 2959 } else if (s->bi_valid > 0) { 2960 put_byte(s, (Byte)s->bi_buf); 2961 } 2962 s->bi_buf = 0; 2963 s->bi_valid = 0; 2964#ifdef DEBUG_ZLIB 2965 s->bits_sent = (s->bits_sent+7) & ~7; 2966#endif 2967} 2968 2969/* =========================================================================== 2970 * Copy a stored block, storing first the length and its 2971 * one's complement if requested. 2972 */ 2973local void copy_block(s, buf, len, header) 2974 deflate_state *s; 2975 charf *buf; /* the input data */ 2976 unsigned len; /* its length */ 2977 int header; /* true if block header must be written */ 2978{ 2979 bi_windup(s); /* align on byte boundary */ 2980 s->last_eob_len = 8; /* enough lookahead for inflate */ 2981 2982 if (header) { 2983 put_short(s, (ush)len); 2984 put_short(s, (ush)~len); 2985#ifdef DEBUG_ZLIB 2986 s->bits_sent += 2*16; 2987#endif 2988 } 2989#ifdef DEBUG_ZLIB 2990 s->bits_sent += (ulg)len<<3; 2991#endif 2992 /* bundle up the put_byte(s, *buf++) calls */ 2993 zmemcpy(&s->pending_buf[s->pending], buf, len); 2994 s->pending += len; 2995} 2996/* --- trees.c */ 2997 2998/* +++ inflate.c */ 2999/* inflate.c -- zlib interface to inflate modules 3000 * Copyright (C) 1995-1996 Mark Adler 3001 * For conditions of distribution and use, see copyright notice in zlib.h 3002 */ 3003 3004/* #include "zutil.h" */ 3005 3006/* +++ infblock.h */ 3007/* infblock.h -- header to use infblock.c 3008 * Copyright (C) 1995-1996 Mark Adler 3009 * For conditions of distribution and use, see copyright notice in zlib.h 3010 */ 3011 3012/* WARNING: this file should *not* be used by applications. It is 3013 part of the implementation of the compression library and is 3014 subject to change. Applications should only use zlib.h. 3015 */ 3016 3017struct inflate_blocks_state; 3018typedef struct inflate_blocks_state FAR inflate_blocks_statef; 3019 3020extern inflate_blocks_statef * inflate_blocks_new OF(( 3021 z_streamp z, 3022 check_func c, /* check function */ 3023 uInt w)); /* window size */ 3024 3025extern int inflate_blocks OF(( 3026 inflate_blocks_statef *, 3027 z_streamp , 3028 int)); /* initial return code */ 3029 3030extern void inflate_blocks_reset OF(( 3031 inflate_blocks_statef *, 3032 z_streamp , 3033 uLongf *)); /* check value on output */ 3034 3035extern int inflate_blocks_free OF(( 3036 inflate_blocks_statef *, 3037 z_streamp , 3038 uLongf *)); /* check value on output */ 3039 3040extern void inflate_set_dictionary OF(( 3041 inflate_blocks_statef *s, 3042 const Bytef *d, /* dictionary */ 3043 uInt n)); /* dictionary length */ 3044 3045extern int inflate_addhistory OF(( 3046 inflate_blocks_statef *, 3047 z_streamp)); 3048 3049extern int inflate_packet_flush OF(( 3050 inflate_blocks_statef *)); 3051/* --- infblock.h */ 3052 3053#ifndef NO_DUMMY_DECL 3054struct inflate_blocks_state {int dummy;}; /* for buggy compilers */ 3055#endif 3056 3057/* inflate private state */ 3058struct internal_state { 3059 3060 /* mode */ 3061 enum { 3062 METHOD, /* waiting for method byte */ 3063 FLAG, /* waiting for flag byte */ 3064 DICT4, /* four dictionary check bytes to go */ 3065 DICT3, /* three dictionary check bytes to go */ 3066 DICT2, /* two dictionary check bytes to go */ 3067 DICT1, /* one dictionary check byte to go */ 3068 DICT0, /* waiting for inflateSetDictionary */ 3069 BLOCKS, /* decompressing blocks */ 3070 CHECK4, /* four check bytes to go */ 3071 CHECK3, /* three check bytes to go */ 3072 CHECK2, /* two check bytes to go */ 3073 CHECK1, /* one check byte to go */ 3074 DONE, /* finished check, done */ 3075 BAD} /* got an error--stay here */ 3076 mode; /* current inflate mode */ 3077 3078 /* mode dependent information */ 3079 union { 3080 uInt method; /* if FLAGS, method byte */ 3081 struct { 3082 uLong was; /* computed check value */ 3083 uLong need; /* stream check value */ 3084 } check; /* if CHECK, check values to compare */ 3085 uInt marker; /* if BAD, inflateSync's marker bytes count */ 3086 } sub; /* submode */ 3087 3088 /* mode independent information */ 3089 int nowrap; /* flag for no wrapper */ 3090 uInt wbits; /* log2(window size) (8..15, defaults to 15) */ 3091 inflate_blocks_statef 3092 *blocks; /* current inflate_blocks state */ 3093 3094}; 3095 3096 3097int inflateReset(z) 3098z_streamp z; 3099{ 3100 uLong c; 3101 3102 if (z == Z_NULL || z->state == Z_NULL) 3103 return Z_STREAM_ERROR; 3104 z->total_in = z->total_out = 0; 3105 z->msg = Z_NULL; 3106 z->state->mode = z->state->nowrap ? BLOCKS : METHOD; 3107 inflate_blocks_reset(z->state->blocks, z, &c); 3108 Trace((stderr, "inflate: reset\n")); 3109 return Z_OK; 3110} 3111 3112 3113int inflateEnd(z) 3114z_streamp z; 3115{ 3116 uLong c; 3117 3118 if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL) 3119 return Z_STREAM_ERROR; 3120 if (z->state->blocks != Z_NULL) 3121 inflate_blocks_free(z->state->blocks, z, &c); 3122 ZFREE(z, z->state); 3123 z->state = Z_NULL; 3124 Trace((stderr, "inflate: end\n")); 3125 return Z_OK; 3126} 3127 3128 3129int inflateInit2_(z, w, version, stream_size) 3130z_streamp z; 3131int w; 3132const char *version; 3133int stream_size; 3134{ 3135 if (version == Z_NULL || version[0] != ZLIB_VERSION[0] || 3136 stream_size != sizeof(z_stream)) 3137 return Z_VERSION_ERROR; 3138 3139 /* initialize state */ 3140 if (z == Z_NULL) 3141 return Z_STREAM_ERROR; 3142 z->msg = Z_NULL; 3143#ifndef NO_ZCFUNCS 3144 if (z->zalloc == Z_NULL) 3145 { 3146 z->zalloc = zcalloc; 3147 z->opaque = (voidpf)0; 3148 } 3149 if (z->zfree == Z_NULL) z->zfree = zcfree; 3150#endif 3151 if ((z->state = (struct internal_state FAR *) 3152 ZALLOC(z,1,sizeof(struct internal_state))) == Z_NULL) 3153 return Z_MEM_ERROR; 3154 z->state->blocks = Z_NULL; 3155 3156 /* handle undocumented nowrap option (no zlib header or check) */ 3157 z->state->nowrap = 0; 3158 if (w < 0) 3159 { 3160 w = - w; 3161 z->state->nowrap = 1; 3162 } 3163 3164 /* set window size */ 3165 if (w < 8 || w > 15) 3166 { 3167 inflateEnd(z); 3168 return Z_STREAM_ERROR; 3169 } 3170 z->state->wbits = (uInt)w; 3171 3172 /* create inflate_blocks state */ 3173 if ((z->state->blocks = 3174 inflate_blocks_new(z, z->state->nowrap ? Z_NULL : adler32, (uInt)1 << w)) 3175 == Z_NULL) 3176 { 3177 inflateEnd(z); 3178 return Z_MEM_ERROR; 3179 } 3180 Trace((stderr, "inflate: allocated\n")); 3181 3182 /* reset state */ 3183 inflateReset(z); 3184 return Z_OK; 3185} 3186 3187 3188int inflateInit_(z, version, stream_size) 3189z_streamp z; 3190const char *version; 3191int stream_size; 3192{ 3193 return inflateInit2_(z, DEF_WBITS, version, stream_size); 3194} 3195 3196 3197#define NEEDBYTE {if(z->avail_in==0)goto empty;r=Z_OK;} 3198#define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++) 3199 3200int inflate(z, f) 3201z_streamp z; 3202int f; 3203{ 3204 int r; 3205 uInt b; 3206 3207 if (z == Z_NULL || z->state == Z_NULL || z->next_in == Z_NULL || f < 0) 3208 return Z_STREAM_ERROR; 3209 r = Z_BUF_ERROR; 3210 while (1) switch (z->state->mode) 3211 { 3212 case METHOD: 3213 NEEDBYTE 3214 if (((z->state->sub.method = NEXTBYTE) & 0xf) != Z_DEFLATED) 3215 { 3216 z->state->mode = BAD; 3217 z->msg = (char*)"unknown compression method"; 3218 z->state->sub.marker = 5; /* can't try inflateSync */ 3219 break; 3220 } 3221 if ((z->state->sub.method >> 4) + 8 > z->state->wbits) 3222 { 3223 z->state->mode = BAD; 3224 z->msg = (char*)"invalid window size"; 3225 z->state->sub.marker = 5; /* can't try inflateSync */ 3226 break; 3227 } 3228 z->state->mode = FLAG; 3229 case FLAG: 3230 NEEDBYTE 3231 b = NEXTBYTE; 3232 if (((z->state->sub.method << 8) + b) % 31) 3233 { 3234 z->state->mode = BAD; 3235 z->msg = (char*)"incorrect header check"; 3236 z->state->sub.marker = 5; /* can't try inflateSync */ 3237 break; 3238 } 3239 Trace((stderr, "inflate: zlib header ok\n")); 3240 if (!(b & PRESET_DICT)) 3241 { 3242 z->state->mode = BLOCKS; 3243 break; 3244 } 3245 z->state->mode = DICT4; 3246 case DICT4: 3247 NEEDBYTE 3248 z->state->sub.check.need = (uLong)NEXTBYTE << 24; 3249 z->state->mode = DICT3; 3250 case DICT3: 3251 NEEDBYTE 3252 z->state->sub.check.need += (uLong)NEXTBYTE << 16; 3253 z->state->mode = DICT2; 3254 case DICT2: 3255 NEEDBYTE 3256 z->state->sub.check.need += (uLong)NEXTBYTE << 8; 3257 z->state->mode = DICT1; 3258 case DICT1: 3259 NEEDBYTE 3260 z->state->sub.check.need += (uLong)NEXTBYTE; 3261 z->adler = z->state->sub.check.need; 3262 z->state->mode = DICT0; 3263 return Z_NEED_DICT; 3264 case DICT0: 3265 z->state->mode = BAD; 3266 z->msg = (char*)"need dictionary"; 3267 z->state->sub.marker = 0; /* can try inflateSync */ 3268 return Z_STREAM_ERROR; 3269 case BLOCKS: 3270 r = inflate_blocks(z->state->blocks, z, r); 3271 if (f == Z_PACKET_FLUSH && z->avail_in == 0 && z->avail_out != 0) 3272 r = inflate_packet_flush(z->state->blocks); 3273 if (r == Z_DATA_ERROR) 3274 { 3275 z->state->mode = BAD; 3276 z->state->sub.marker = 0; /* can try inflateSync */ 3277 break; 3278 } 3279 if (r != Z_STREAM_END) 3280 return r; 3281 r = Z_OK; 3282 inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was); 3283 if (z->state->nowrap) 3284 { 3285 z->state->mode = DONE; 3286 break; 3287 } 3288 z->state->mode = CHECK4; 3289 case CHECK4: 3290 NEEDBYTE 3291 z->state->sub.check.need = (uLong)NEXTBYTE << 24; 3292 z->state->mode = CHECK3; 3293 case CHECK3: 3294 NEEDBYTE 3295 z->state->sub.check.need += (uLong)NEXTBYTE << 16; 3296 z->state->mode = CHECK2; 3297 case CHECK2: 3298 NEEDBYTE 3299 z->state->sub.check.need += (uLong)NEXTBYTE << 8; 3300 z->state->mode = CHECK1; 3301 case CHECK1: 3302 NEEDBYTE 3303 z->state->sub.check.need += (uLong)NEXTBYTE; 3304 3305 if (z->state->sub.check.was != z->state->sub.check.need) 3306 { 3307 z->state->mode = BAD; 3308 z->msg = (char*)"incorrect data check"; 3309 z->state->sub.marker = 5; /* can't try inflateSync */ 3310 break; 3311 } 3312 Trace((stderr, "inflate: zlib check ok\n")); 3313 z->state->mode = DONE; 3314 case DONE: 3315 return Z_STREAM_END; 3316 case BAD: 3317 return Z_DATA_ERROR; 3318 default: 3319 return Z_STREAM_ERROR; 3320 } 3321 3322 empty: 3323 if (f != Z_PACKET_FLUSH) 3324 return r; 3325 z->state->mode = BAD; 3326 z->msg = (char *)"need more for packet flush"; 3327 z->state->sub.marker = 0; /* can try inflateSync */ 3328 return Z_DATA_ERROR; 3329} 3330 3331 3332int inflateSetDictionary(z, dictionary, dictLength) 3333z_streamp z; 3334const Bytef *dictionary; 3335uInt dictLength; 3336{ 3337 uInt length = dictLength; 3338 3339 if (z == Z_NULL || z->state == Z_NULL || z->state->mode != DICT0) 3340 return Z_STREAM_ERROR; 3341 3342 if (adler32(1L, dictionary, dictLength) != z->adler) return Z_DATA_ERROR; 3343 z->adler = 1L; 3344 3345 if (length >= ((uInt)1<<z->state->wbits)) 3346 { 3347 length = (1<<z->state->wbits)-1; 3348 dictionary += dictLength - length; 3349 } 3350 inflate_set_dictionary(z->state->blocks, dictionary, length); 3351 z->state->mode = BLOCKS; 3352 return Z_OK; 3353} 3354 3355/* 3356 * This subroutine adds the data at next_in/avail_in to the output history 3357 * without performing any output. The output buffer must be "caught up"; 3358 * i.e. no pending output (hence s->read equals s->write), and the state must 3359 * be BLOCKS (i.e. we should be willing to see the start of a series of 3360 * BLOCKS). On exit, the output will also be caught up, and the checksum 3361 * will have been updated if need be. 3362 */ 3363 3364int inflateIncomp(z) 3365z_stream *z; 3366{ 3367 if (z->state->mode != BLOCKS) 3368 return Z_DATA_ERROR; 3369 return inflate_addhistory(z->state->blocks, z); 3370} 3371 3372 3373int inflateSync(z) 3374z_streamp z; 3375{ 3376 uInt n; /* number of bytes to look at */ 3377 Bytef *p; /* pointer to bytes */ 3378 uInt m; /* number of marker bytes found in a row */ 3379 uLong r, w; /* temporaries to save total_in and total_out */ 3380 3381 /* set up */ 3382 if (z == Z_NULL || z->state == Z_NULL) 3383 return Z_STREAM_ERROR; 3384 if (z->state->mode != BAD) 3385 { 3386 z->state->mode = BAD; 3387 z->state->sub.marker = 0; 3388 } 3389 if ((n = z->avail_in) == 0) 3390 return Z_BUF_ERROR; 3391 p = z->next_in; 3392 m = z->state->sub.marker; 3393 3394 /* search */ 3395 while (n && m < 4) 3396 { 3397 if (*p == (Byte)(m < 2 ? 0 : 0xff)) 3398 m++; 3399 else if (*p) 3400 m = 0; 3401 else 3402 m = 4 - m; 3403 p++, n--; 3404 } 3405 3406 /* restore */ 3407 z->total_in += p - z->next_in; 3408 z->next_in = p; 3409 z->avail_in = n; 3410 z->state->sub.marker = m; 3411 3412 /* return no joy or set up to restart on a new block */ 3413 if (m != 4) 3414 return Z_DATA_ERROR; 3415 r = z->total_in; w = z->total_out; 3416 inflateReset(z); 3417 z->total_in = r; z->total_out = w; 3418 z->state->mode = BLOCKS; 3419 return Z_OK; 3420} 3421 3422#undef NEEDBYTE 3423#undef NEXTBYTE 3424/* --- inflate.c */ 3425 3426/* +++ infblock.c */ 3427/* infblock.c -- interpret and process block types to last block 3428 * Copyright (C) 1995-1996 Mark Adler 3429 * For conditions of distribution and use, see copyright notice in zlib.h 3430 */ 3431 3432/* #include "zutil.h" */ 3433/* #include "infblock.h" */ 3434 3435/* +++ inftrees.h */ 3436/* inftrees.h -- header to use inftrees.c 3437 * Copyright (C) 1995-1996 Mark Adler 3438 * For conditions of distribution and use, see copyright notice in zlib.h 3439 */ 3440 3441/* WARNING: this file should *not* be used by applications. It is 3442 part of the implementation of the compression library and is 3443 subject to change. Applications should only use zlib.h. 3444 */ 3445 3446/* Huffman code lookup table entry--this entry is four bytes for machines 3447 that have 16-bit pointers (e.g. PC's in the small or medium model). */ 3448 3449typedef struct inflate_huft_s FAR inflate_huft; 3450 3451struct inflate_huft_s { 3452 union { 3453 struct { 3454 Byte Exop; /* number of extra bits or operation */ 3455 Byte Bits; /* number of bits in this code or subcode */ 3456 } what; 3457 Bytef *pad; /* pad structure to a power of 2 (4 bytes for */ 3458 } word; /* 16-bit, 8 bytes for 32-bit machines) */ 3459 union { 3460 uInt Base; /* literal, length base, or distance base */ 3461 inflate_huft *Next; /* pointer to next level of table */ 3462 } more; 3463}; 3464 3465#ifdef DEBUG_ZLIB 3466 extern uInt inflate_hufts; 3467#endif 3468 3469extern int inflate_trees_bits OF(( 3470 uIntf *, /* 19 code lengths */ 3471 uIntf *, /* bits tree desired/actual depth */ 3472 inflate_huft * FAR *, /* bits tree result */ 3473 z_streamp )); /* for zalloc, zfree functions */ 3474 3475extern int inflate_trees_dynamic OF(( 3476 uInt, /* number of literal/length codes */ 3477 uInt, /* number of distance codes */ 3478 uIntf *, /* that many (total) code lengths */ 3479 uIntf *, /* literal desired/actual bit depth */ 3480 uIntf *, /* distance desired/actual bit depth */ 3481 inflate_huft * FAR *, /* literal/length tree result */ 3482 inflate_huft * FAR *, /* distance tree result */ 3483 z_streamp )); /* for zalloc, zfree functions */ 3484 3485extern int inflate_trees_fixed OF(( 3486 uIntf *, /* literal desired/actual bit depth */ 3487 uIntf *, /* distance desired/actual bit depth */ 3488 inflate_huft * FAR *, /* literal/length tree result */ 3489 inflate_huft * FAR *)); /* distance tree result */ 3490 3491extern int inflate_trees_free OF(( 3492 inflate_huft *, /* tables to free */ 3493 z_streamp )); /* for zfree function */ 3494 3495/* --- inftrees.h */ 3496 3497/* +++ infcodes.h */ 3498/* infcodes.h -- header to use infcodes.c 3499 * Copyright (C) 1995-1996 Mark Adler 3500 * For conditions of distribution and use, see copyright notice in zlib.h 3501 */ 3502 3503/* WARNING: this file should *not* be used by applications. It is 3504 part of the implementation of the compression library and is 3505 subject to change. Applications should only use zlib.h. 3506 */ 3507 3508struct inflate_codes_state; 3509typedef struct inflate_codes_state FAR inflate_codes_statef; 3510 3511extern inflate_codes_statef *inflate_codes_new OF(( 3512 uInt, uInt, 3513 inflate_huft *, inflate_huft *, 3514 z_streamp )); 3515 3516extern int inflate_codes OF(( 3517 inflate_blocks_statef *, 3518 z_streamp , 3519 int)); 3520 3521extern void inflate_codes_free OF(( 3522 inflate_codes_statef *, 3523 z_streamp )); 3524 3525/* --- infcodes.h */ 3526 3527/* +++ infutil.h */ 3528/* infutil.h -- types and macros common to blocks and codes 3529 * Copyright (C) 1995-1996 Mark Adler 3530 * For conditions of distribution and use, see copyright notice in zlib.h 3531 */ 3532 3533/* WARNING: this file should *not* be used by applications. It is 3534 part of the implementation of the compression library and is 3535 subject to change. Applications should only use zlib.h. 3536 */ 3537 3538#ifndef _INFUTIL_H 3539#define _INFUTIL_H 3540 3541typedef enum { 3542 TYPE, /* get type bits (3, including end bit) */ 3543 LENS, /* get lengths for stored */ 3544 STORED, /* processing stored block */ 3545 TABLE, /* get table lengths */ 3546 BTREE, /* get bit lengths tree for a dynamic block */ 3547 DTREE, /* get length, distance trees for a dynamic block */ 3548 CODES, /* processing fixed or dynamic block */ 3549 DRY, /* output remaining window bytes */ 3550 DONEB, /* finished last block, done */ 3551 BADB} /* got a data error--stuck here */ 3552inflate_block_mode; 3553 3554/* inflate blocks semi-private state */ 3555struct inflate_blocks_state { 3556 3557 /* mode */ 3558 inflate_block_mode mode; /* current inflate_block mode */ 3559 3560 /* mode dependent information */ 3561 union { 3562 uInt left; /* if STORED, bytes left to copy */ 3563 struct { 3564 uInt table; /* table lengths (14 bits) */ 3565 uInt index; /* index into blens (or border) */ 3566 uIntf *blens; /* bit lengths of codes */ 3567 uInt bb; /* bit length tree depth */ 3568 inflate_huft *tb; /* bit length decoding tree */ 3569 } trees; /* if DTREE, decoding info for trees */ 3570 struct { 3571 inflate_huft *tl; 3572 inflate_huft *td; /* trees to free */ 3573 inflate_codes_statef 3574 *codes; 3575 } decode; /* if CODES, current state */ 3576 } sub; /* submode */ 3577 uInt last; /* true if this block is the last block */ 3578 3579 /* mode independent information */ 3580 uInt bitk; /* bits in bit buffer */ 3581 uLong bitb; /* bit buffer */ 3582 Bytef *window; /* sliding window */ 3583 Bytef *end; /* one byte after sliding window */ 3584 Bytef *read; /* window read pointer */ 3585 Bytef *write; /* window write pointer */ 3586 check_func checkfn; /* check function */ 3587 uLong check; /* check on output */ 3588 3589}; 3590 3591 3592/* defines for inflate input/output */ 3593/* update pointers and return */ 3594#define UPDBITS {s->bitb=b;s->bitk=k;} 3595#define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;} 3596#define UPDOUT {s->write=q;} 3597#define UPDATE {UPDBITS UPDIN UPDOUT} 3598#define LEAVE {UPDATE return inflate_flush(s,z,r);} 3599/* get bytes and bits */ 3600#define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;} 3601#define NEEDBYTE {if(n)r=Z_OK;else LEAVE} 3602#define NEXTBYTE (n--,*p++) 3603#define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}} 3604#define DUMPBITS(j) {b>>=(j);k-=(j);} 3605/* output bytes */ 3606#define WAVAIL (uInt)(q<s->read?s->read-q-1:s->end-q) 3607#define LOADOUT {q=s->write;m=(uInt)WAVAIL;} 3608#define WWRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}} 3609#define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT} 3610#define NEEDOUT {if(m==0){WWRAP if(m==0){FLUSH WWRAP if(m==0) LEAVE}}r=Z_OK;} 3611#define OUTBYTE(a) {*q++=(Byte)(a);m--;} 3612/* load local pointers */ 3613#define LOAD {LOADIN LOADOUT} 3614 3615/* masks for lower bits (size given to avoid silly warnings with Visual C++) */ 3616extern uInt inflate_mask[17]; 3617 3618/* copy as much as possible from the sliding window to the output area */ 3619extern int inflate_flush OF(( 3620 inflate_blocks_statef *, 3621 z_streamp , 3622 int)); 3623 3624#ifndef NO_DUMMY_DECL 3625struct internal_state {int dummy;}; /* for buggy compilers */ 3626#endif 3627 3628#endif 3629/* --- infutil.h */ 3630 3631#ifndef NO_DUMMY_DECL 3632struct inflate_codes_state {int dummy;}; /* for buggy compilers */ 3633#endif 3634 3635/* Table for deflate from PKZIP's appnote.txt. */ 3636local const uInt border[] = { /* Order of the bit length code lengths */ 3637 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; 3638 3639/* 3640 Notes beyond the 1.93a appnote.txt: 3641 3642 1. Distance pointers never point before the beginning of the output 3643 stream. 3644 2. Distance pointers can point back across blocks, up to 32k away. 3645 3. There is an implied maximum of 7 bits for the bit length table and 3646 15 bits for the actual data. 3647 4. If only one code exists, then it is encoded using one bit. (Zero 3648 would be more efficient, but perhaps a little confusing.) If two 3649 codes exist, they are coded using one bit each (0 and 1). 3650 5. There is no way of sending zero distance codes--a dummy must be 3651 sent if there are none. (History: a pre 2.0 version of PKZIP would 3652 store blocks with no distance codes, but this was discovered to be 3653 too harsh a criterion.) Valid only for 1.93a. 2.04c does allow 3654 zero distance codes, which is sent as one code of zero bits in 3655 length. 3656 6. There are up to 286 literal/length codes. Code 256 represents the 3657 end-of-block. Note however that the static length tree defines 3658 288 codes just to fill out the Huffman codes. Codes 286 and 287 3659 cannot be used though, since there is no length base or extra bits 3660 defined for them. Similarily, there are up to 30 distance codes. 3661 However, static trees define 32 codes (all 5 bits) to fill out the 3662 Huffman codes, but the last two had better not show up in the data. 3663 7. Unzip can check dynamic Huffman blocks for complete code sets. 3664 The exception is that a single code would not be complete (see #4). 3665 8. The five bits following the block type is really the number of 3666 literal codes sent minus 257. 3667 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits 3668 (1+6+6). Therefore, to output three times the length, you output 3669 three codes (1+1+1), whereas to output four times the same length, 3670 you only need two codes (1+3). Hmm. 3671 10. In the tree reconstruction algorithm, Code = Code + Increment 3672 only if BitLength(i) is not zero. (Pretty obvious.) 3673 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19) 3674 12. Note: length code 284 can represent 227-258, but length code 285 3675 really is 258. The last length deserves its own, short code 3676 since it gets used a lot in very redundant files. The length 3677 258 is special since 258 - 3 (the min match length) is 255. 3678 13. The literal/length and distance code bit lengths are read as a 3679 single stream of lengths. It is possible (and advantageous) for 3680 a repeat code (16, 17, or 18) to go across the boundary between 3681 the two sets of lengths. 3682 */ 3683 3684 3685void inflate_blocks_reset(s, z, c) 3686inflate_blocks_statef *s; 3687z_streamp z; 3688uLongf *c; 3689{ 3690 if (s->checkfn != Z_NULL) 3691 *c = s->check; 3692 if (s->mode == BTREE || s->mode == DTREE) 3693 ZFREE(z, s->sub.trees.blens); 3694 if (s->mode == CODES) 3695 { 3696 inflate_codes_free(s->sub.decode.codes, z); 3697 inflate_trees_free(s->sub.decode.td, z); 3698 inflate_trees_free(s->sub.decode.tl, z); 3699 } 3700 s->mode = TYPE; 3701 s->bitk = 0; 3702 s->bitb = 0; 3703 s->read = s->write = s->window; 3704 if (s->checkfn != Z_NULL) 3705 z->adler = s->check = (*s->checkfn)(0L, Z_NULL, 0); 3706 Trace((stderr, "inflate: blocks reset\n")); 3707} 3708 3709 3710inflate_blocks_statef *inflate_blocks_new(z, c, w) 3711z_streamp z; 3712check_func c; 3713uInt w; 3714{ 3715 inflate_blocks_statef *s; 3716 3717 if ((s = (inflate_blocks_statef *)ZALLOC 3718 (z,1,sizeof(struct inflate_blocks_state))) == Z_NULL) 3719 return s; 3720 if ((s->window = (Bytef *)ZALLOC(z, 1, w)) == Z_NULL) 3721 { 3722 ZFREE(z, s); 3723 return Z_NULL; 3724 } 3725 s->end = s->window + w; 3726 s->checkfn = c; 3727 s->mode = TYPE; 3728 Trace((stderr, "inflate: blocks allocated\n")); 3729 inflate_blocks_reset(s, z, &s->check); 3730 return s; 3731} 3732 3733 3734#ifdef DEBUG_ZLIB 3735 extern uInt inflate_hufts; 3736#endif 3737int inflate_blocks(s, z, r) 3738inflate_blocks_statef *s; 3739z_streamp z; 3740int r; 3741{ 3742 uInt t; /* temporary storage */ 3743 uLong b; /* bit buffer */ 3744 uInt k; /* bits in bit buffer */ 3745 Bytef *p; /* input data pointer */ 3746 uInt n; /* bytes available there */ 3747 Bytef *q; /* output window write pointer */ 3748 uInt m; /* bytes to end of window or read pointer */ 3749 3750 /* copy input/output information to locals (UPDATE macro restores) */ 3751 LOAD 3752 3753 /* process input based on current state */ 3754 while (1) switch (s->mode) 3755 { 3756 case TYPE: 3757 NEEDBITS(3) 3758 t = (uInt)b & 7; 3759 s->last = t & 1; 3760 switch (t >> 1) 3761 { 3762 case 0: /* stored */ 3763 Trace((stderr, "inflate: stored block%s\n", 3764 s->last ? " (last)" : "")); 3765 DUMPBITS(3) 3766 t = k & 7; /* go to byte boundary */ 3767 DUMPBITS(t) 3768 s->mode = LENS; /* get length of stored block */ 3769 break; 3770 case 1: /* fixed */ 3771 Trace((stderr, "inflate: fixed codes block%s\n", 3772 s->last ? " (last)" : "")); 3773 { 3774 uInt bl, bd; 3775 inflate_huft *tl, *td; 3776 3777 inflate_trees_fixed(&bl, &bd, &tl, &td); 3778 s->sub.decode.codes = inflate_codes_new(bl, bd, tl, td, z); 3779 if (s->sub.decode.codes == Z_NULL) 3780 { 3781 r = Z_MEM_ERROR; 3782 LEAVE 3783 } 3784 s->sub.decode.tl = Z_NULL; /* don't try to free these */ 3785 s->sub.decode.td = Z_NULL; 3786 } 3787 DUMPBITS(3) 3788 s->mode = CODES; 3789 break; 3790 case 2: /* dynamic */ 3791 Trace((stderr, "inflate: dynamic codes block%s\n", 3792 s->last ? " (last)" : "")); 3793 DUMPBITS(3) 3794 s->mode = TABLE; 3795 break; 3796 case 3: /* illegal */ 3797 DUMPBITS(3) 3798 s->mode = BADB; 3799 z->msg = (char*)"invalid block type"; 3800 r = Z_DATA_ERROR; 3801 LEAVE 3802 } 3803 break; 3804 case LENS: 3805 NEEDBITS(32) 3806 if ((((~b) >> 16) & 0xffff) != (b & 0xffff)) 3807 { 3808 s->mode = BADB; 3809 z->msg = (char*)"invalid stored block lengths"; 3810 r = Z_DATA_ERROR; 3811 LEAVE 3812 } 3813 s->sub.left = (uInt)b & 0xffff; 3814 b = k = 0; /* dump bits */ 3815 Tracev((stderr, "inflate: stored length %u\n", s->sub.left)); 3816 s->mode = s->sub.left ? STORED : (s->last ? DRY : TYPE); 3817 break; 3818 case STORED: 3819 if (n == 0) 3820 LEAVE 3821 NEEDOUT 3822 t = s->sub.left; 3823 if (t > n) t = n; 3824 if (t > m) t = m; 3825 zmemcpy(q, p, t); 3826 p += t; n -= t; 3827 q += t; m -= t; 3828 if ((s->sub.left -= t) != 0) 3829 break; 3830 Tracev((stderr, "inflate: stored end, %lu total out\n", 3831 z->total_out + (q >= s->read ? q - s->read : 3832 (s->end - s->read) + (q - s->window)))); 3833 s->mode = s->last ? DRY : TYPE; 3834 break; 3835 case TABLE: 3836 NEEDBITS(14) 3837 s->sub.trees.table = t = (uInt)b & 0x3fff; 3838#ifndef PKZIP_BUG_WORKAROUND 3839 if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29) 3840 { 3841 s->mode = BADB; 3842 z->msg = (char*)"too many length or distance symbols"; 3843 r = Z_DATA_ERROR; 3844 LEAVE 3845 } 3846#endif 3847 t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f); 3848 if (t < 19) 3849 t = 19; 3850 if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL) 3851 { 3852 r = Z_MEM_ERROR; 3853 LEAVE 3854 } 3855 DUMPBITS(14) 3856 s->sub.trees.index = 0; 3857 Tracev((stderr, "inflate: table sizes ok\n")); 3858 s->mode = BTREE; 3859 case BTREE: 3860 while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10)) 3861 { 3862 NEEDBITS(3) 3863 s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7; 3864 DUMPBITS(3) 3865 } 3866 while (s->sub.trees.index < 19) 3867 s->sub.trees.blens[border[s->sub.trees.index++]] = 0; 3868 s->sub.trees.bb = 7; 3869 t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb, 3870 &s->sub.trees.tb, z); 3871 if (t != Z_OK) 3872 { 3873 r = t; 3874 if (r == Z_DATA_ERROR) { 3875 ZFREE(z, s->sub.trees.blens); 3876 s->mode = BADB; 3877 } 3878 LEAVE 3879 } 3880 s->sub.trees.index = 0; 3881 Tracev((stderr, "inflate: bits tree ok\n")); 3882 s->mode = DTREE; 3883 case DTREE: 3884 while (t = s->sub.trees.table, 3885 s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f)) 3886 { 3887 inflate_huft *h; 3888 uInt i, j, c; 3889 3890 t = s->sub.trees.bb; 3891 NEEDBITS(t) 3892 h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]); 3893 t = h->word.what.Bits; 3894 c = h->more.Base; 3895 if (c < 16) 3896 { 3897 DUMPBITS(t) 3898 s->sub.trees.blens[s->sub.trees.index++] = c; 3899 } 3900 else /* c == 16..18 */ 3901 { 3902 i = c == 18 ? 7 : c - 14; 3903 j = c == 18 ? 11 : 3; 3904 NEEDBITS(t + i) 3905 DUMPBITS(t) 3906 j += (uInt)b & inflate_mask[i]; 3907 DUMPBITS(i) 3908 i = s->sub.trees.index; 3909 t = s->sub.trees.table; 3910 if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) || 3911 (c == 16 && i < 1)) 3912 { 3913 inflate_trees_free(s->sub.trees.tb, z); 3914 ZFREE(z, s->sub.trees.blens); 3915 s->mode = BADB; 3916 z->msg = (char*)"invalid bit length repeat"; 3917 r = Z_DATA_ERROR; 3918 LEAVE 3919 } 3920 c = c == 16 ? s->sub.trees.blens[i - 1] : 0; 3921 do { 3922 s->sub.trees.blens[i++] = c; 3923 } while (--j); 3924 s->sub.trees.index = i; 3925 } 3926 } 3927 inflate_trees_free(s->sub.trees.tb, z); 3928 s->sub.trees.tb = Z_NULL; 3929 { 3930 uInt bl, bd; 3931 inflate_huft *tl, *td; 3932 inflate_codes_statef *c; 3933 3934 bl = 9; /* must be <= 9 for lookahead assumptions */ 3935 bd = 6; /* must be <= 9 for lookahead assumptions */ 3936 t = s->sub.trees.table; 3937#ifdef DEBUG_ZLIB 3938 inflate_hufts = 0; 3939#endif 3940 t = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f), 3941 s->sub.trees.blens, &bl, &bd, &tl, &td, z); 3942 if (t != Z_OK) 3943 { 3944 if (t == (uInt)Z_DATA_ERROR) { 3945 ZFREE(z, s->sub.trees.blens); 3946 s->mode = BADB; 3947 } 3948 r = t; 3949 LEAVE 3950 } 3951 Tracev((stderr, "inflate: trees ok, %d * %d bytes used\n", 3952 inflate_hufts, sizeof(inflate_huft))); 3953 if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL) 3954 { 3955 inflate_trees_free(td, z); 3956 inflate_trees_free(tl, z); 3957 r = Z_MEM_ERROR; 3958 LEAVE 3959 } 3960 /* 3961 * this ZFREE must occur *BEFORE* we mess with sub.decode, because 3962 * sub.trees is union'd with sub.decode. 3963 */ 3964 ZFREE(z, s->sub.trees.blens); 3965 s->sub.decode.codes = c; 3966 s->sub.decode.tl = tl; 3967 s->sub.decode.td = td; 3968 } 3969 s->mode = CODES; 3970 case CODES: 3971 UPDATE 3972 if ((r = inflate_codes(s, z, r)) != Z_STREAM_END) 3973 return inflate_flush(s, z, r); 3974 r = Z_OK; 3975 inflate_codes_free(s->sub.decode.codes, z); 3976 inflate_trees_free(s->sub.decode.td, z); 3977 inflate_trees_free(s->sub.decode.tl, z); 3978 LOAD 3979 Tracev((stderr, "inflate: codes end, %lu total out\n", 3980 z->total_out + (q >= s->read ? q - s->read : 3981 (s->end - s->read) + (q - s->window)))); 3982 if (!s->last) 3983 { 3984 s->mode = TYPE; 3985 break; 3986 } 3987 if (k > 7) /* return unused byte, if any */ 3988 { 3989 Assert(k < 16, "inflate_codes grabbed too many bytes") 3990 k -= 8; 3991 n++; 3992 p--; /* can always return one */ 3993 } 3994 s->mode = DRY; 3995 case DRY: 3996 FLUSH 3997 if (s->read != s->write) 3998 LEAVE 3999 s->mode = DONEB; 4000 case DONEB: 4001 r = Z_STREAM_END; 4002 LEAVE 4003 case BADB: 4004 r = Z_DATA_ERROR; 4005 LEAVE 4006 default: 4007 r = Z_STREAM_ERROR; 4008 LEAVE 4009 } 4010} 4011 4012 4013int inflate_blocks_free(s, z, c) 4014inflate_blocks_statef *s; 4015z_streamp z; 4016uLongf *c; 4017{ 4018 inflate_blocks_reset(s, z, c); 4019 ZFREE(z, s->window); 4020 ZFREE(z, s); 4021 Trace((stderr, "inflate: blocks freed\n")); 4022 return Z_OK; 4023} 4024 4025 4026void inflate_set_dictionary(s, d, n) 4027inflate_blocks_statef *s; 4028const Bytef *d; 4029uInt n; 4030{ 4031 zmemcpy((charf *)s->window, d, n); 4032 s->read = s->write = s->window + n; 4033} 4034 4035/* 4036 * This subroutine adds the data at next_in/avail_in to the output history 4037 * without performing any output. The output buffer must be "caught up"; 4038 * i.e. no pending output (hence s->read equals s->write), and the state must 4039 * be BLOCKS (i.e. we should be willing to see the start of a series of 4040 * BLOCKS). On exit, the output will also be caught up, and the checksum 4041 * will have been updated if need be. 4042 */ 4043int inflate_addhistory(s, z) 4044inflate_blocks_statef *s; 4045z_stream *z; 4046{ 4047 uLong b; /* bit buffer */ /* NOT USED HERE */ 4048 uInt k; /* bits in bit buffer */ /* NOT USED HERE */ 4049 uInt t; /* temporary storage */ 4050 Bytef *p; /* input data pointer */ 4051 uInt n; /* bytes available there */ 4052 Bytef *q; /* output window write pointer */ 4053 uInt m; /* bytes to end of window or read pointer */ 4054 4055 if (s->read != s->write) 4056 return Z_STREAM_ERROR; 4057 if (s->mode != TYPE) 4058 return Z_DATA_ERROR; 4059 4060 /* we're ready to rock */ 4061 LOAD 4062 /* while there is input ready, copy to output buffer, moving 4063 * pointers as needed. 4064 */ 4065 while (n) { 4066 t = n; /* how many to do */ 4067 /* is there room until end of buffer? */ 4068 if (t > m) t = m; 4069 /* update check information */ 4070 if (s->checkfn != Z_NULL) 4071 s->check = (*s->checkfn)(s->check, q, t); 4072 zmemcpy(q, p, t); 4073 q += t; 4074 p += t; 4075 n -= t; 4076 z->total_out += t; 4077 s->read = q; /* drag read pointer forward */ 4078/* WWRAP */ /* expand WWRAP macro by hand to handle s->read */ 4079 if (q == s->end) { 4080 s->read = q = s->window; 4081 m = WAVAIL; 4082 } 4083 } 4084 UPDATE 4085 return Z_OK; 4086} 4087 4088 4089/* 4090 * At the end of a Deflate-compressed PPP packet, we expect to have seen 4091 * a `stored' block type value but not the (zero) length bytes. 4092 */ 4093int inflate_packet_flush(s) 4094 inflate_blocks_statef *s; 4095{ 4096 if (s->mode != LENS) 4097 return Z_DATA_ERROR; 4098 s->mode = TYPE; 4099 return Z_OK; 4100} 4101/* --- infblock.c */ 4102 4103/* +++ inftrees.c */ 4104/* inftrees.c -- generate Huffman trees for efficient decoding 4105 * Copyright (C) 1995-1996 Mark Adler 4106 * For conditions of distribution and use, see copyright notice in zlib.h 4107 */ 4108 4109/* #include "zutil.h" */ 4110/* #include "inftrees.h" */ 4111 4112char inflate_copyright[] = " inflate 1.0.4 Copyright 1995-1996 Mark Adler "; 4113/* 4114 If you use the zlib library in a product, an acknowledgment is welcome 4115 in the documentation of your product. If for some reason you cannot 4116 include such an acknowledgment, I would appreciate that you keep this 4117 copyright string in the executable of your product. 4118 */ 4119 4120#ifndef NO_DUMMY_DECL 4121struct internal_state {int dummy;}; /* for buggy compilers */ 4122#endif 4123 4124/* simplify the use of the inflate_huft type with some defines */ 4125#define base more.Base 4126#define next more.Next 4127#define exop word.what.Exop 4128#define bits word.what.Bits 4129 4130 4131local int huft_build OF(( 4132 uIntf *, /* code lengths in bits */ 4133 uInt, /* number of codes */ 4134 uInt, /* number of "simple" codes */ 4135 const uIntf *, /* list of base values for non-simple codes */ 4136 const uIntf *, /* list of extra bits for non-simple codes */ 4137 inflate_huft * FAR*,/* result: starting table */ 4138 uIntf *, /* maximum lookup bits (returns actual) */ 4139 z_streamp )); /* for zalloc function */ 4140 4141local voidpf falloc OF(( 4142 voidpf, /* opaque pointer (not used) */ 4143 uInt, /* number of items */ 4144 uInt)); /* size of item */ 4145 4146/* Tables for deflate from PKZIP's appnote.txt. */ 4147local const uInt cplens[31] = { /* Copy lengths for literal codes 257..285 */ 4148 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, 4149 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0}; 4150 /* see note #13 above about 258 */ 4151local const uInt cplext[31] = { /* Extra bits for literal codes 257..285 */ 4152 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 4153 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 112, 112}; /* 112==invalid */ 4154local const uInt cpdist[30] = { /* Copy offsets for distance codes 0..29 */ 4155 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, 4156 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145, 4157 8193, 12289, 16385, 24577}; 4158local const uInt cpdext[30] = { /* Extra bits for distance codes */ 4159 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 4160 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 4161 12, 12, 13, 13}; 4162 4163/* 4164 Huffman code decoding is performed using a multi-level table lookup. 4165 The fastest way to decode is to simply build a lookup table whose 4166 size is determined by the longest code. However, the time it takes 4167 to build this table can also be a factor if the data being decoded 4168 is not very long. The most common codes are necessarily the 4169 shortest codes, so those codes dominate the decoding time, and hence 4170 the speed. The idea is you can have a shorter table that decodes the 4171 shorter, more probable codes, and then point to subsidiary tables for 4172 the longer codes. The time it costs to decode the longer codes is 4173 then traded against the time it takes to make longer tables. 4174 4175 This results of this trade are in the variables lbits and dbits 4176 below. lbits is the number of bits the first level table for literal/ 4177 length codes can decode in one step, and dbits is the same thing for 4178 the distance codes. Subsequent tables are also less than or equal to 4179 those sizes. These values may be adjusted either when all of the 4180 codes are shorter than that, in which case the longest code length in 4181 bits is used, or when the shortest code is *longer* than the requested 4182 table size, in which case the length of the shortest code in bits is 4183 used. 4184 4185 There are two different values for the two tables, since they code a 4186 different number of possibilities each. The literal/length table 4187 codes 286 possible values, or in a flat code, a little over eight 4188 bits. The distance table codes 30 possible values, or a little less 4189 than five bits, flat. The optimum values for speed end up being 4190 about one bit more than those, so lbits is 8+1 and dbits is 5+1. 4191 The optimum values may differ though from machine to machine, and 4192 possibly even between compilers. Your mileage may vary. 4193 */ 4194 4195 4196/* If BMAX needs to be larger than 16, then h and x[] should be uLong. */ 4197#define BMAX 15 /* maximum bit length of any code */ 4198#define N_MAX 288 /* maximum number of codes in any set */ 4199 4200#ifdef DEBUG_ZLIB 4201 uInt inflate_hufts; 4202#endif 4203 4204local int huft_build(b, n, s, d, e, t, m, zs) 4205uIntf *b; /* code lengths in bits (all assumed <= BMAX) */ 4206uInt n; /* number of codes (assumed <= N_MAX) */ 4207uInt s; /* number of simple-valued codes (0..s-1) */ 4208const uIntf *d; /* list of base values for non-simple codes */ 4209const uIntf *e; /* list of extra bits for non-simple codes */ 4210inflate_huft * FAR *t; /* result: starting table */ 4211uIntf *m; /* maximum lookup bits, returns actual */ 4212z_streamp zs; /* for zalloc function */ 4213/* Given a list of code lengths and a maximum table size, make a set of 4214 tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR 4215 if the given code set is incomplete (the tables are still built in this 4216 case), Z_DATA_ERROR if the input is invalid (an over-subscribed set of 4217 lengths), or Z_MEM_ERROR if not enough memory. */ 4218{ 4219 4220 uInt a; /* counter for codes of length k */ 4221 uInt c[BMAX+1]; /* bit length count table */ 4222 uInt f; /* i repeats in table every f entries */ 4223 int g; /* maximum code length */ 4224 int h; /* table level */ 4225 register uInt i; /* counter, current code */ 4226 register uInt j; /* counter */ 4227 register int k; /* number of bits in current code */ 4228 int l; /* bits per table (returned in m) */ 4229 register uIntf *p; /* pointer into c[], b[], or v[] */ 4230 inflate_huft *q; /* points to current table */ 4231 struct inflate_huft_s r; /* table entry for structure assignment */ 4232 inflate_huft *u[BMAX]; /* table stack */ 4233 uInt v[N_MAX]; /* values in order of bit length */ 4234 register int w; /* bits before this table == (l * h) */ 4235 uInt x[BMAX+1]; /* bit offsets, then code stack */ 4236 uIntf *xp; /* pointer into x */ 4237 int y; /* number of dummy codes added */ 4238 uInt z; /* number of entries in current table */ 4239 4240 4241 /* Generate counts for each bit length */ 4242 p = c; 4243#define C0 *p++ = 0; 4244#define C2 C0 C0 C0 C0 4245#define C4 C2 C2 C2 C2 4246 C4 /* clear c[]--assume BMAX+1 is 16 */ 4247 p = b; i = n; 4248 do { 4249 c[*p++]++; /* assume all entries <= BMAX */ 4250 } while (--i); 4251 if (c[0] == n) /* null input--all zero length codes */ 4252 { 4253 *t = (inflate_huft *)Z_NULL; 4254 *m = 0; 4255 return Z_OK; 4256 } 4257 4258 4259 /* Find minimum and maximum length, bound *m by those */ 4260 l = *m; 4261 for (j = 1; j <= BMAX; j++) 4262 if (c[j]) 4263 break; 4264 k = j; /* minimum code length */ 4265 if ((uInt)l < j) 4266 l = j; 4267 for (i = BMAX; i; i--) 4268 if (c[i]) 4269 break; 4270 g = i; /* maximum code length */ 4271 if ((uInt)l > i) 4272 l = i; 4273 *m = l; 4274 4275 4276 /* Adjust last length count to fill out codes, if needed */ 4277 for (y = 1 << j; j < i; j++, y <<= 1) 4278 if ((y -= c[j]) < 0) 4279 return Z_DATA_ERROR; 4280 if ((y -= c[i]) < 0) 4281 return Z_DATA_ERROR; 4282 c[i] += y; 4283 4284 4285 /* Generate starting offsets into the value table for each length */ 4286 x[1] = j = 0; 4287 p = c + 1; xp = x + 2; 4288 while (--i) { /* note that i == g from above */ 4289 *xp++ = (j += *p++); 4290 } 4291 4292 4293 /* Make a table of values in order of bit lengths */ 4294 p = b; i = 0; 4295 do { 4296 if ((j = *p++) != 0) 4297 v[x[j]++] = i; 4298 } while (++i < n); 4299 n = x[g]; /* set n to length of v */ 4300 4301 4302 /* Generate the Huffman codes and for each, make the table entries */ 4303 x[0] = i = 0; /* first Huffman code is zero */ 4304 p = v; /* grab values in bit order */ 4305 h = -1; /* no tables yet--level -1 */ 4306 w = -l; /* bits decoded == (l * h) */ 4307 u[0] = (inflate_huft *)Z_NULL; /* just to keep compilers happy */ 4308 q = (inflate_huft *)Z_NULL; /* ditto */ 4309 z = 0; /* ditto */ 4310 4311 /* go through the bit lengths (k already is bits in shortest code) */ 4312 for (; k <= g; k++) 4313 { 4314 a = c[k]; 4315 while (a--) 4316 { 4317 /* here i is the Huffman code of length k bits for value *p */ 4318 /* make tables up to required level */ 4319 while (k > w + l) 4320 { 4321 h++; 4322 w += l; /* previous table always l bits */ 4323 4324 /* compute minimum size table less than or equal to l bits */ 4325 z = g - w; 4326 z = z > (uInt)l ? l : z; /* table size upper limit */ 4327 if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */ 4328 { /* too few codes for k-w bit table */ 4329 f -= a + 1; /* deduct codes from patterns left */ 4330 xp = c + k; 4331 if (j < z) 4332 while (++j < z) /* try smaller tables up to z bits */ 4333 { 4334 if ((f <<= 1) <= *++xp) 4335 break; /* enough codes to use up j bits */ 4336 f -= *xp; /* else deduct codes from patterns */ 4337 } 4338 } 4339 z = 1 << j; /* table entries for j-bit table */ 4340 4341 /* allocate and link in new table */ 4342 if ((q = (inflate_huft *)ZALLOC 4343 (zs,z + 1,sizeof(inflate_huft))) == Z_NULL) 4344 { 4345 if (h) 4346 inflate_trees_free(u[0], zs); 4347 return Z_MEM_ERROR; /* not enough memory */ 4348 } 4349#ifdef DEBUG_ZLIB 4350 inflate_hufts += z + 1; 4351#endif 4352 *t = q + 1; /* link to list for huft_free() */ 4353 *(t = &(q->next)) = Z_NULL; 4354 u[h] = ++q; /* table starts after link */ 4355 4356 /* connect to last table, if there is one */ 4357 if (h) 4358 { 4359 x[h] = i; /* save pattern for backing up */ 4360 r.bits = (Byte)l; /* bits to dump before this table */ 4361 r.exop = (Byte)j; /* bits in this table */ 4362 r.next = q; /* pointer to this table */ 4363 j = i >> (w - l); /* (get around Turbo C bug) */ 4364 u[h-1][j] = r; /* connect to last table */ 4365 } 4366 } 4367 4368 /* set up table entry in r */ 4369 r.bits = (Byte)(k - w); 4370 if (p >= v + n) 4371 r.exop = 128 + 64; /* out of values--invalid code */ 4372 else if (*p < s) 4373 { 4374 r.exop = (Byte)(*p < 256 ? 0 : 32 + 64); /* 256 is end-of-block */ 4375 r.base = *p++; /* simple code is just the value */ 4376 } 4377 else 4378 { 4379 r.exop = (Byte)(e[*p - s] + 16 + 64);/* non-simple--look up in lists */ 4380 r.base = d[*p++ - s]; 4381 } 4382 4383 /* fill code-like entries with r */ 4384 f = 1 << (k - w); 4385 for (j = i >> w; j < z; j += f) 4386 q[j] = r; 4387 4388 /* backwards increment the k-bit code i */ 4389 for (j = 1 << (k - 1); i & j; j >>= 1) 4390 i ^= j; 4391 i ^= j; 4392 4393 /* backup over finished tables */ 4394 while ((i & ((1 << w) - 1)) != x[h]) 4395 { 4396 h--; /* don't need to update q */ 4397 w -= l; 4398 } 4399 } 4400 } 4401 4402 4403 /* Return Z_BUF_ERROR if we were given an incomplete table */ 4404 return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK; 4405} 4406 4407 4408int inflate_trees_bits(c, bb, tb, z) 4409uIntf *c; /* 19 code lengths */ 4410uIntf *bb; /* bits tree desired/actual depth */ 4411inflate_huft * FAR *tb; /* bits tree result */ 4412z_streamp z; /* for zfree function */ 4413{ 4414 int r; 4415 4416 r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL, tb, bb, z); 4417 if (r == Z_DATA_ERROR) 4418 z->msg = (char*)"oversubscribed dynamic bit lengths tree"; 4419 else if (r == Z_BUF_ERROR || *bb == 0) 4420 { 4421 inflate_trees_free(*tb, z); 4422 z->msg = (char*)"incomplete dynamic bit lengths tree"; 4423 r = Z_DATA_ERROR; 4424 } 4425 return r; 4426} 4427 4428 4429int inflate_trees_dynamic(nl, nd, c, bl, bd, tl, td, z) 4430uInt nl; /* number of literal/length codes */ 4431uInt nd; /* number of distance codes */ 4432uIntf *c; /* that many (total) code lengths */ 4433uIntf *bl; /* literal desired/actual bit depth */ 4434uIntf *bd; /* distance desired/actual bit depth */ 4435inflate_huft * FAR *tl; /* literal/length tree result */ 4436inflate_huft * FAR *td; /* distance tree result */ 4437z_streamp z; /* for zfree function */ 4438{ 4439 int r; 4440 4441 /* build literal/length tree */ 4442 r = huft_build(c, nl, 257, cplens, cplext, tl, bl, z); 4443 if (r != Z_OK || *bl == 0) 4444 { 4445 if (r == Z_DATA_ERROR) 4446 z->msg = (char*)"oversubscribed literal/length tree"; 4447 else if (r != Z_MEM_ERROR) 4448 { 4449 inflate_trees_free(*tl, z); 4450 z->msg = (char*)"incomplete literal/length tree"; 4451 r = Z_DATA_ERROR; 4452 } 4453 return r; 4454 } 4455 4456 /* build distance tree */ 4457 r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, z); 4458 if (r != Z_OK || (*bd == 0 && nl > 257)) 4459 { 4460 if (r == Z_DATA_ERROR) 4461 z->msg = (char*)"oversubscribed distance tree"; 4462 else if (r == Z_BUF_ERROR) { 4463#ifdef PKZIP_BUG_WORKAROUND 4464 r = Z_OK; 4465 } 4466#else 4467 inflate_trees_free(*td, z); 4468 z->msg = (char*)"incomplete distance tree"; 4469 r = Z_DATA_ERROR; 4470 } 4471 else if (r != Z_MEM_ERROR) 4472 { 4473 z->msg = (char*)"empty distance tree with lengths"; 4474 r = Z_DATA_ERROR; 4475 } 4476 inflate_trees_free(*tl, z); 4477 return r; 4478#endif 4479 } 4480 4481 /* done */ 4482 return Z_OK; 4483} 4484 4485 4486/* build fixed tables only once--keep them here */ 4487local int fixed_built = 0; 4488#define FIXEDH 530 /* number of hufts used by fixed tables */ 4489local inflate_huft fixed_mem[FIXEDH]; 4490local uInt fixed_bl; 4491local uInt fixed_bd; 4492local inflate_huft *fixed_tl; 4493local inflate_huft *fixed_td; 4494 4495 4496local voidpf falloc(q, n, s) 4497voidpf q; /* opaque pointer */ 4498uInt n; /* number of items */ 4499uInt s; /* size of item */ 4500{ 4501 Assert(s == sizeof(inflate_huft) && n <= *(intf *)q, 4502 "inflate_trees falloc overflow"); 4503 *(intf *)q -= n+s-s; /* s-s to avoid warning */ 4504 return (voidpf)(fixed_mem + *(intf *)q); 4505} 4506 4507 4508int inflate_trees_fixed(bl, bd, tl, td) 4509uIntf *bl; /* literal desired/actual bit depth */ 4510uIntf *bd; /* distance desired/actual bit depth */ 4511inflate_huft * FAR *tl; /* literal/length tree result */ 4512inflate_huft * FAR *td; /* distance tree result */ 4513{ 4514 /* build fixed tables if not already (multiple overlapped executions ok) */ 4515 if (!fixed_built) 4516 { 4517 int k; /* temporary variable */ 4518 unsigned c[288]; /* length list for huft_build */ 4519 z_stream z; /* for falloc function */ 4520 int f = FIXEDH; /* number of hufts left in fixed_mem */ 4521 4522 /* set up fake z_stream for memory routines */ 4523 z.zalloc = falloc; 4524 z.zfree = Z_NULL; 4525 z.opaque = (voidpf)&f; 4526 4527 /* literal table */ 4528 for (k = 0; k < 144; k++) 4529 c[k] = 8; 4530 for (; k < 256; k++) 4531 c[k] = 9; 4532 for (; k < 280; k++) 4533 c[k] = 7; 4534 for (; k < 288; k++) 4535 c[k] = 8; 4536 fixed_bl = 7; 4537 huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl, &z); 4538 4539 /* distance table */ 4540 for (k = 0; k < 30; k++) 4541 c[k] = 5; 4542 fixed_bd = 5; 4543 huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd, &z); 4544 4545 /* done */ 4546 Assert(f == 0, "invalid build of fixed tables"); 4547 fixed_built = 1; 4548 } 4549 *bl = fixed_bl; 4550 *bd = fixed_bd; 4551 *tl = fixed_tl; 4552 *td = fixed_td; 4553 return Z_OK; 4554} 4555 4556 4557int inflate_trees_free(t, z) 4558inflate_huft *t; /* table to free */ 4559z_streamp z; /* for zfree function */ 4560/* Free the malloc'ed tables built by huft_build(), which makes a linked 4561 list of the tables it made, with the links in a dummy first entry of 4562 each table. */ 4563{ 4564 register inflate_huft *p, *q, *r; 4565 4566 /* Reverse linked list */ 4567 p = Z_NULL; 4568 q = t; 4569 while (q != Z_NULL) 4570 { 4571 r = (q - 1)->next; 4572 (q - 1)->next = p; 4573 p = q; 4574 q = r; 4575 } 4576 /* Go through linked list, freeing from the malloced (t[-1]) address. */ 4577 while (p != Z_NULL) 4578 { 4579 q = (--p)->next; 4580 ZFREE(z,p); 4581 p = q; 4582 } 4583 return Z_OK; 4584} 4585/* --- inftrees.c */ 4586 4587/* +++ infcodes.c */ 4588/* infcodes.c -- process literals and length/distance pairs 4589 * Copyright (C) 1995-1996 Mark Adler 4590 * For conditions of distribution and use, see copyright notice in zlib.h 4591 */ 4592 4593/* #include "zutil.h" */ 4594/* #include "inftrees.h" */ 4595/* #include "infblock.h" */ 4596/* #include "infcodes.h" */ 4597/* #include "infutil.h" */ 4598 4599/* +++ inffast.h */ 4600/* inffast.h -- header to use inffast.c 4601 * Copyright (C) 1995-1996 Mark Adler 4602 * For conditions of distribution and use, see copyright notice in zlib.h 4603 */ 4604 4605/* WARNING: this file should *not* be used by applications. It is 4606 part of the implementation of the compression library and is 4607 subject to change. Applications should only use zlib.h. 4608 */ 4609 4610extern int inflate_fast OF(( 4611 uInt, 4612 uInt, 4613 inflate_huft *, 4614 inflate_huft *, 4615 inflate_blocks_statef *, 4616 z_streamp )); 4617/* --- inffast.h */ 4618 4619/* simplify the use of the inflate_huft type with some defines */ 4620#define base more.Base 4621#define next more.Next 4622#define exop word.what.Exop 4623#define bits word.what.Bits 4624 4625/* inflate codes private state */ 4626struct inflate_codes_state { 4627 4628 /* mode */ 4629 enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */ 4630 START, /* x: set up for LEN */ 4631 LEN, /* i: get length/literal/eob next */ 4632 LENEXT, /* i: getting length extra (have base) */ 4633 DIST, /* i: get distance next */ 4634 DISTEXT, /* i: getting distance extra */ 4635 COPY, /* o: copying bytes in window, waiting for space */ 4636 LIT, /* o: got literal, waiting for output space */ 4637 WASH, /* o: got eob, possibly still output waiting */ 4638 END, /* x: got eob and all data flushed */ 4639 BADCODE} /* x: got error */ 4640 mode; /* current inflate_codes mode */ 4641 4642 /* mode dependent information */ 4643 uInt len; 4644 union { 4645 struct { 4646 inflate_huft *tree; /* pointer into tree */ 4647 uInt need; /* bits needed */ 4648 } code; /* if LEN or DIST, where in tree */ 4649 uInt lit; /* if LIT, literal */ 4650 struct { 4651 uInt get; /* bits to get for extra */ 4652 uInt dist; /* distance back to copy from */ 4653 } copy; /* if EXT or COPY, where and how much */ 4654 } sub; /* submode */ 4655 4656 /* mode independent information */ 4657 Byte lbits; /* ltree bits decoded per branch */ 4658 Byte dbits; /* dtree bits decoder per branch */ 4659 inflate_huft *ltree; /* literal/length/eob tree */ 4660 inflate_huft *dtree; /* distance tree */ 4661 4662}; 4663 4664 4665inflate_codes_statef *inflate_codes_new(bl, bd, tl, td, z) 4666uInt bl, bd; 4667inflate_huft *tl; 4668inflate_huft *td; /* need separate declaration for Borland C++ */ 4669z_streamp z; 4670{ 4671 inflate_codes_statef *c; 4672 4673 if ((c = (inflate_codes_statef *) 4674 ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL) 4675 { 4676 c->mode = START; 4677 c->lbits = (Byte)bl; 4678 c->dbits = (Byte)bd; 4679 c->ltree = tl; 4680 c->dtree = td; 4681 Tracev((stderr, "inflate: codes new\n")); 4682 } 4683 return c; 4684} 4685 4686 4687int inflate_codes(s, z, r) 4688inflate_blocks_statef *s; 4689z_streamp z; 4690int r; 4691{ 4692 uInt j; /* temporary storage */ 4693 inflate_huft *t; /* temporary pointer */ 4694 uInt e; /* extra bits or operation */ 4695 uLong b; /* bit buffer */ 4696 uInt k; /* bits in bit buffer */ 4697 Bytef *p; /* input data pointer */ 4698 uInt n; /* bytes available there */ 4699 Bytef *q; /* output window write pointer */ 4700 uInt m; /* bytes to end of window or read pointer */ 4701 Bytef *f; /* pointer to copy strings from */ 4702 inflate_codes_statef *c = s->sub.decode.codes; /* codes state */ 4703 4704 /* copy input/output information to locals (UPDATE macro restores) */ 4705 LOAD 4706 4707 /* process input and output based on current state */ 4708 while (1) switch (c->mode) 4709 { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */ 4710 case START: /* x: set up for LEN */ 4711#ifndef SLOW 4712 if (m >= 258 && n >= 10) 4713 { 4714 UPDATE 4715 r = inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z); 4716 LOAD 4717 if (r != Z_OK) 4718 { 4719 c->mode = r == Z_STREAM_END ? WASH : BADCODE; 4720 break; 4721 } 4722 } 4723#endif /* !SLOW */ 4724 c->sub.code.need = c->lbits; 4725 c->sub.code.tree = c->ltree; 4726 c->mode = LEN; 4727 case LEN: /* i: get length/literal/eob next */ 4728 j = c->sub.code.need; 4729 NEEDBITS(j) 4730 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]); 4731 DUMPBITS(t->bits) 4732 e = (uInt)(t->exop); 4733 if (e == 0) /* literal */ 4734 { 4735 c->sub.lit = t->base; 4736 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ? 4737 "inflate: literal '%c'\n" : 4738 "inflate: literal 0x%02x\n", t->base)); 4739 c->mode = LIT; 4740 break; 4741 } 4742 if (e & 16) /* length */ 4743 { 4744 c->sub.copy.get = e & 15; 4745 c->len = t->base; 4746 c->mode = LENEXT; 4747 break; 4748 } 4749 if ((e & 64) == 0) /* next table */ 4750 { 4751 c->sub.code.need = e; 4752 c->sub.code.tree = t->next; 4753 break; 4754 } 4755 if (e & 32) /* end of block */ 4756 { 4757 Tracevv((stderr, "inflate: end of block\n")); 4758 c->mode = WASH; 4759 break; 4760 } 4761 c->mode = BADCODE; /* invalid code */ 4762 z->msg = (char*)"invalid literal/length code"; 4763 r = Z_DATA_ERROR; 4764 LEAVE 4765 case LENEXT: /* i: getting length extra (have base) */ 4766 j = c->sub.copy.get; 4767 NEEDBITS(j) 4768 c->len += (uInt)b & inflate_mask[j]; 4769 DUMPBITS(j) 4770 c->sub.code.need = c->dbits; 4771 c->sub.code.tree = c->dtree; 4772 Tracevv((stderr, "inflate: length %u\n", c->len)); 4773 c->mode = DIST; 4774 case DIST: /* i: get distance next */ 4775 j = c->sub.code.need; 4776 NEEDBITS(j) 4777 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]); 4778 DUMPBITS(t->bits) 4779 e = (uInt)(t->exop); 4780 if (e & 16) /* distance */ 4781 { 4782 c->sub.copy.get = e & 15; 4783 c->sub.copy.dist = t->base; 4784 c->mode = DISTEXT; 4785 break; 4786 } 4787 if ((e & 64) == 0) /* next table */ 4788 { 4789 c->sub.code.need = e; 4790 c->sub.code.tree = t->next; 4791 break; 4792 } 4793 c->mode = BADCODE; /* invalid code */ 4794 z->msg = (char*)"invalid distance code"; 4795 r = Z_DATA_ERROR; 4796 LEAVE 4797 case DISTEXT: /* i: getting distance extra */ 4798 j = c->sub.copy.get; 4799 NEEDBITS(j) 4800 c->sub.copy.dist += (uInt)b & inflate_mask[j]; 4801 DUMPBITS(j) 4802 Tracevv((stderr, "inflate: distance %u\n", c->sub.copy.dist)); 4803 c->mode = COPY; 4804 case COPY: /* o: copying bytes in window, waiting for space */ 4805#ifndef __TURBOC__ /* Turbo C bug for following expression */ 4806 f = (uInt)(q - s->window) < c->sub.copy.dist ? 4807 s->end - (c->sub.copy.dist - (q - s->window)) : 4808 q - c->sub.copy.dist; 4809#else 4810 f = q - c->sub.copy.dist; 4811 if ((uInt)(q - s->window) < c->sub.copy.dist) 4812 f = s->end - (c->sub.copy.dist - (uInt)(q - s->window)); 4813#endif 4814 while (c->len) 4815 { 4816 NEEDOUT 4817 OUTBYTE(*f++) 4818 if (f == s->end) 4819 f = s->window; 4820 c->len--; 4821 } 4822 c->mode = START; 4823 break; 4824 case LIT: /* o: got literal, waiting for output space */ 4825 NEEDOUT 4826 OUTBYTE(c->sub.lit) 4827 c->mode = START; 4828 break; 4829 case WASH: /* o: got eob, possibly more output */ 4830 FLUSH 4831 if (s->read != s->write) 4832 LEAVE 4833 c->mode = END; 4834 case END: 4835 r = Z_STREAM_END; 4836 LEAVE 4837 case BADCODE: /* x: got error */ 4838 r = Z_DATA_ERROR; 4839 LEAVE 4840 default: 4841 r = Z_STREAM_ERROR; 4842 LEAVE 4843 } 4844} 4845 4846 4847void inflate_codes_free(c, z) 4848inflate_codes_statef *c; 4849z_streamp z; 4850{ 4851 ZFREE(z, c); 4852 Tracev((stderr, "inflate: codes free\n")); 4853} 4854/* --- infcodes.c */ 4855 4856/* +++ infutil.c */ 4857/* inflate_util.c -- data and routines common to blocks and codes 4858 * Copyright (C) 1995-1996 Mark Adler 4859 * For conditions of distribution and use, see copyright notice in zlib.h 4860 */ 4861 4862/* #include "zutil.h" */ 4863/* #include "infblock.h" */ 4864/* #include "inftrees.h" */ 4865/* #include "infcodes.h" */ 4866/* #include "infutil.h" */ 4867 4868#ifndef NO_DUMMY_DECL 4869struct inflate_codes_state {int dummy;}; /* for buggy compilers */ 4870#endif 4871 4872/* And'ing with mask[n] masks the lower n bits */ 4873uInt inflate_mask[17] = { 4874 0x0000, 4875 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff, 4876 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff 4877}; 4878 4879 4880/* copy as much as possible from the sliding window to the output area */ 4881int inflate_flush(s, z, r) 4882inflate_blocks_statef *s; 4883z_streamp z; 4884int r; 4885{ 4886 uInt n; 4887 Bytef *p; 4888 Bytef *q; 4889 4890 /* local copies of source and destination pointers */ 4891 p = z->next_out; 4892 q = s->read; 4893 4894 /* compute number of bytes to copy as far as end of window */ 4895 n = (uInt)((q <= s->write ? s->write : s->end) - q); 4896 if (n > z->avail_out) n = z->avail_out; 4897 if (n && r == Z_BUF_ERROR) r = Z_OK; 4898 4899 /* update counters */ 4900 z->avail_out -= n; 4901 z->total_out += n; 4902 4903 /* update check information */ 4904 if (s->checkfn != Z_NULL) 4905 z->adler = s->check = (*s->checkfn)(s->check, q, n); 4906 4907 /* copy as far as end of window */ 4908 if (p != Z_NULL) { 4909 zmemcpy(p, q, n); 4910 p += n; 4911 } 4912 q += n; 4913 4914 /* see if more to copy at beginning of window */ 4915 if (q == s->end) 4916 { 4917 /* wrap pointers */ 4918 q = s->window; 4919 if (s->write == s->end) 4920 s->write = s->window; 4921 4922 /* compute bytes to copy */ 4923 n = (uInt)(s->write - q); 4924 if (n > z->avail_out) n = z->avail_out; 4925 if (n && r == Z_BUF_ERROR) r = Z_OK; 4926 4927 /* update counters */ 4928 z->avail_out -= n; 4929 z->total_out += n; 4930 4931 /* update check information */ 4932 if (s->checkfn != Z_NULL) 4933 z->adler = s->check = (*s->checkfn)(s->check, q, n); 4934 4935 /* copy */ 4936 if (p != Z_NULL) { 4937 zmemcpy(p, q, n); 4938 p += n; 4939 } 4940 q += n; 4941 } 4942 4943 /* update pointers */ 4944 z->next_out = p; 4945 s->read = q; 4946 4947 /* done */ 4948 return r; 4949} 4950/* --- infutil.c */ 4951 4952/* +++ inffast.c */ 4953/* inffast.c -- process literals and length/distance pairs fast 4954 * Copyright (C) 1995-1996 Mark Adler 4955 * For conditions of distribution and use, see copyright notice in zlib.h 4956 */ 4957 4958/* #include "zutil.h" */ 4959/* #include "inftrees.h" */ 4960/* #include "infblock.h" */ 4961/* #include "infcodes.h" */ 4962/* #include "infutil.h" */ 4963/* #include "inffast.h" */ 4964 4965#ifndef NO_DUMMY_DECL 4966struct inflate_codes_state {int dummy;}; /* for buggy compilers */ 4967#endif 4968 4969/* simplify the use of the inflate_huft type with some defines */ 4970#define base more.Base 4971#define next more.Next 4972#define exop word.what.Exop 4973#define bits word.what.Bits 4974 4975/* macros for bit input with no checking and for returning unused bytes */ 4976#define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}} 4977#define UNGRAB {n+=(c=k>>3);p-=c;k&=7;} 4978 4979/* Called with number of bytes left to write in window at least 258 4980 (the maximum string length) and number of input bytes available 4981 at least ten. The ten bytes are six bytes for the longest length/ 4982 distance pair plus four bytes for overloading the bit buffer. */ 4983 4984int inflate_fast(bl, bd, tl, td, s, z) 4985uInt bl, bd; 4986inflate_huft *tl; 4987inflate_huft *td; /* need separate declaration for Borland C++ */ 4988inflate_blocks_statef *s; 4989z_streamp z; 4990{ 4991 inflate_huft *t; /* temporary pointer */ 4992 uInt e; /* extra bits or operation */ 4993 uLong b; /* bit buffer */ 4994 uInt k; /* bits in bit buffer */ 4995 Bytef *p; /* input data pointer */ 4996 uInt n; /* bytes available there */ 4997 Bytef *q; /* output window write pointer */ 4998 uInt m; /* bytes to end of window or read pointer */ 4999 uInt ml; /* mask for literal/length tree */ 5000 uInt md; /* mask for distance tree */ 5001 uInt c; /* bytes to copy */ 5002 uInt d; /* distance back to copy from */ 5003 Bytef *r; /* copy source pointer */ 5004 5005 /* load input, output, bit values */ 5006 LOAD 5007 5008 /* initialize masks */ 5009 ml = inflate_mask[bl]; 5010 md = inflate_mask[bd]; 5011 5012 /* do until not enough input or output space for fast loop */ 5013 do { /* assume called with m >= 258 && n >= 10 */ 5014 /* get literal/length code */ 5015 GRABBITS(20) /* max bits for literal/length code */ 5016 if ((e = (t = tl + ((uInt)b & ml))->exop) == 0) 5017 { 5018 DUMPBITS(t->bits) 5019 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ? 5020 "inflate: * literal '%c'\n" : 5021 "inflate: * literal 0x%02x\n", t->base)); 5022 *q++ = (Byte)t->base; 5023 m--; 5024 continue; 5025 } 5026 do { 5027 DUMPBITS(t->bits) 5028 if (e & 16) 5029 { 5030 /* get extra bits for length */ 5031 e &= 15; 5032 c = t->base + ((uInt)b & inflate_mask[e]); 5033 DUMPBITS(e) 5034 Tracevv((stderr, "inflate: * length %u\n", c)); 5035 5036 /* decode distance base of block to copy */ 5037 GRABBITS(15); /* max bits for distance code */ 5038 e = (t = td + ((uInt)b & md))->exop; 5039 do { 5040 DUMPBITS(t->bits) 5041 if (e & 16) 5042 { 5043 /* get extra bits to add to distance base */ 5044 e &= 15; 5045 GRABBITS(e) /* get extra bits (up to 13) */ 5046 d = t->base + ((uInt)b & inflate_mask[e]); 5047 DUMPBITS(e) 5048 Tracevv((stderr, "inflate: * distance %u\n", d)); 5049 5050 /* do the copy */ 5051 m -= c; 5052 if ((uInt)(q - s->window) >= d) /* offset before dest */ 5053 { /* just copy */ 5054 r = q - d; 5055 *q++ = *r++; c--; /* minimum count is three, */ 5056 *q++ = *r++; c--; /* so unroll loop a little */ 5057 } 5058 else /* else offset after destination */ 5059 { 5060 e = d - (uInt)(q - s->window); /* bytes from offset to end */ 5061 r = s->end - e; /* pointer to offset */ 5062 if (c > e) /* if source crosses, */ 5063 { 5064 c -= e; /* copy to end of window */ 5065 do { 5066 *q++ = *r++; 5067 } while (--e); 5068 r = s->window; /* copy rest from start of window */ 5069 } 5070 } 5071 do { /* copy all or what's left */ 5072 *q++ = *r++; 5073 } while (--c); 5074 break; 5075 } 5076 else if ((e & 64) == 0) 5077 e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop; 5078 else 5079 { 5080 z->msg = (char*)"invalid distance code"; 5081 UNGRAB 5082 UPDATE 5083 return Z_DATA_ERROR; 5084 } 5085 } while (1); 5086 break; 5087 } 5088 if ((e & 64) == 0) 5089 { 5090 if ((e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop) == 0) 5091 { 5092 DUMPBITS(t->bits) 5093 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ? 5094 "inflate: * literal '%c'\n" : 5095 "inflate: * literal 0x%02x\n", t->base)); 5096 *q++ = (Byte)t->base; 5097 m--; 5098 break; 5099 } 5100 } 5101 else if (e & 32) 5102 { 5103 Tracevv((stderr, "inflate: * end of block\n")); 5104 UNGRAB 5105 UPDATE 5106 return Z_STREAM_END; 5107 } 5108 else 5109 { 5110 z->msg = (char*)"invalid literal/length code"; 5111 UNGRAB 5112 UPDATE 5113 return Z_DATA_ERROR; 5114 } 5115 } while (1); 5116 } while (m >= 258 && n >= 10); 5117 5118 /* not enough input or output--restore pointers and return */ 5119 UNGRAB 5120 UPDATE 5121 return Z_OK; 5122} 5123/* --- inffast.c */ 5124 5125/* +++ zutil.c */ 5126/* zutil.c -- target dependent utility functions for the compression library 5127 * Copyright (C) 1995-1996 Jean-loup Gailly. 5128 * For conditions of distribution and use, see copyright notice in zlib.h 5129 */ 5130 5131/* From: zutil.c,v 1.17 1996/07/24 13:41:12 me Exp $ */ 5132 5133#ifdef DEBUG_ZLIB 5134#include <stdio.h> 5135#endif 5136 5137/* #include "zutil.h" */ 5138 5139#ifndef NO_DUMMY_DECL 5140struct internal_state {int dummy;}; /* for buggy compilers */ 5141#endif 5142 5143#ifndef STDC 5144extern void exit OF((int)); 5145#endif 5146 5147static const char *z_errmsg[10] = { 5148"need dictionary", /* Z_NEED_DICT 2 */ 5149"stream end", /* Z_STREAM_END 1 */ 5150"", /* Z_OK 0 */ 5151"file error", /* Z_ERRNO (-1) */ 5152"stream error", /* Z_STREAM_ERROR (-2) */ 5153"data error", /* Z_DATA_ERROR (-3) */ 5154"insufficient memory", /* Z_MEM_ERROR (-4) */ 5155"buffer error", /* Z_BUF_ERROR (-5) */ 5156"incompatible version",/* Z_VERSION_ERROR (-6) */ 5157""}; 5158 5159 5160const char *zlibVersion() 5161{ 5162 return ZLIB_VERSION; 5163} 5164 5165#ifdef DEBUG_ZLIB 5166void z_error (m) 5167 char *m; 5168{ 5169 fprintf(stderr, "%s\n", m); 5170 exit(1); 5171} 5172#endif 5173 5174#ifndef HAVE_MEMCPY 5175 5176void zmemcpy(dest, source, len) 5177 Bytef* dest; 5178 Bytef* source; 5179 uInt len; 5180{ 5181 if (len == 0) return; 5182 do { 5183 *dest++ = *source++; /* ??? to be unrolled */ 5184 } while (--len != 0); 5185} 5186 5187int zmemcmp(s1, s2, len) 5188 Bytef* s1; 5189 Bytef* s2; 5190 uInt len; 5191{ 5192 uInt j; 5193 5194 for (j = 0; j < len; j++) { 5195 if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1; 5196 } 5197 return 0; 5198} 5199 5200void zmemzero(dest, len) 5201 Bytef* dest; 5202 uInt len; 5203{ 5204 if (len == 0) return; 5205 do { 5206 *dest++ = 0; /* ??? to be unrolled */ 5207 } while (--len != 0); 5208} 5209#endif 5210 5211#ifdef __TURBOC__ 5212#if (defined( __BORLANDC__) || !defined(SMALL_MEDIUM)) && !defined(__32BIT__) 5213/* Small and medium model in Turbo C are for now limited to near allocation 5214 * with reduced MAX_WBITS and MAX_MEM_LEVEL 5215 */ 5216# define MY_ZCALLOC 5217 5218/* Turbo C malloc() does not allow dynamic allocation of 64K bytes 5219 * and farmalloc(64K) returns a pointer with an offset of 8, so we 5220 * must fix the pointer. Warning: the pointer must be put back to its 5221 * original form in order to free it, use zcfree(). 5222 */ 5223 5224#define MAX_PTR 10 5225/* 10*64K = 640K */ 5226 5227local int next_ptr = 0; 5228 5229typedef struct ptr_table_s { 5230 voidpf org_ptr; 5231 voidpf new_ptr; 5232} ptr_table; 5233 5234local ptr_table table[MAX_PTR]; 5235/* This table is used to remember the original form of pointers 5236 * to large buffers (64K). Such pointers are normalized with a zero offset. 5237 * Since MSDOS is not a preemptive multitasking OS, this table is not 5238 * protected from concurrent access. This hack doesn't work anyway on 5239 * a protected system like OS/2. Use Microsoft C instead. 5240 */ 5241 5242voidpf zcalloc (voidpf opaque, unsigned items, unsigned size) 5243{ 5244 voidpf buf = opaque; /* just to make some compilers happy */ 5245 ulg bsize = (ulg)items*size; 5246 5247 /* If we allocate less than 65520 bytes, we assume that farmalloc 5248 * will return a usable pointer which doesn't have to be normalized. 5249 */ 5250 if (bsize < 65520L) { 5251 buf = farmalloc(bsize); 5252 if (*(ush*)&buf != 0) return buf; 5253 } else { 5254 buf = farmalloc(bsize + 16L); 5255 } 5256 if (buf == NULL || next_ptr >= MAX_PTR) return NULL; 5257 table[next_ptr].org_ptr = buf; 5258 5259 /* Normalize the pointer to seg:0 */ 5260 *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4; 5261 *(ush*)&buf = 0; 5262 table[next_ptr++].new_ptr = buf; 5263 return buf; 5264} 5265 5266void zcfree (voidpf opaque, voidpf ptr) 5267{ 5268 int n; 5269 if (*(ush*)&ptr != 0) { /* object < 64K */ 5270 farfree(ptr); 5271 return; 5272 } 5273 /* Find the original pointer */ 5274 for (n = 0; n < next_ptr; n++) { 5275 if (ptr != table[n].new_ptr) continue; 5276 5277 farfree(table[n].org_ptr); 5278 while (++n < next_ptr) { 5279 table[n-1] = table[n]; 5280 } 5281 next_ptr--; 5282 return; 5283 } 5284 ptr = opaque; /* just to make some compilers happy */ 5285 Assert(0, "zcfree: ptr not found"); 5286} 5287#endif 5288#endif /* __TURBOC__ */ 5289 5290 5291#if defined(M_I86) && !defined(__32BIT__) 5292/* Microsoft C in 16-bit mode */ 5293 5294# define MY_ZCALLOC 5295 5296#if (!defined(_MSC_VER) || (_MSC_VER < 600)) 5297# define _halloc halloc 5298# define _hfree hfree 5299#endif 5300 5301voidpf zcalloc (voidpf opaque, unsigned items, unsigned size) 5302{ 5303 if (opaque) opaque = 0; /* to make compiler happy */ 5304 return _halloc((long)items, size); 5305} 5306 5307void zcfree (voidpf opaque, voidpf ptr) 5308{ 5309 if (opaque) opaque = 0; /* to make compiler happy */ 5310 _hfree(ptr); 5311} 5312 5313#endif /* MSC */ 5314 5315 5316#ifndef MY_ZCALLOC /* Any system without a special alloc function */ 5317 5318#ifndef STDC 5319extern voidp calloc OF((uInt items, uInt size)); 5320extern void free OF((voidpf ptr)); 5321#endif 5322 5323voidpf zcalloc (opaque, items, size) 5324 voidpf opaque; 5325 unsigned items; 5326 unsigned size; 5327{ 5328 if (opaque) items += size - size; /* make compiler happy */ 5329 return (voidpf)calloc(items, size); 5330} 5331 5332void zcfree (opaque, ptr) 5333 voidpf opaque; 5334 voidpf ptr; 5335{ 5336 free(ptr); 5337 if (opaque) return; /* make compiler happy */ 5338} 5339 5340#endif /* MY_ZCALLOC */ 5341/* --- zutil.c */ 5342 5343/* +++ adler32.c */ 5344/* adler32.c -- compute the Adler-32 checksum of a data stream 5345 * Copyright (C) 1995-1996 Mark Adler 5346 * For conditions of distribution and use, see copyright notice in zlib.h 5347 */ 5348 5349/* From: adler32.c,v 1.10 1996/05/22 11:52:18 me Exp $ */ 5350 5351/* #include "zlib.h" */ 5352 5353#define BASE 65521L /* largest prime smaller than 65536 */ 5354#define NMAX 5552 5355/* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */ 5356 5357#define DO1(buf,i) {s1 += buf[(i)]; s2 += s1;} 5358#define DO2(buf,i) DO1(buf,i); DO1(buf,(i)+1); 5359#define DO4(buf,i) DO2(buf,i); DO2(buf,(i)+2); 5360#define DO8(buf,i) DO4(buf,i); DO4(buf,(i)+4); 5361#define DO16(buf) DO8(buf,0); DO8(buf,8); 5362 5363/* ========================================================================= */ 5364uLong adler32(adler, buf, len) 5365 uLong adler; 5366 const Bytef *buf; 5367 uInt len; 5368{ 5369 unsigned long s1 = adler & 0xffff; 5370 unsigned long s2 = (adler >> 16) & 0xffff; 5371 int k; 5372 5373 if (buf == Z_NULL) return 1L; 5374 5375 while (len > 0) { 5376 k = len < NMAX ? len : NMAX; 5377 len -= k; 5378 while (k >= 16) { 5379 DO16(buf); 5380 buf += 16; 5381 k -= 16; 5382 } 5383 if (k != 0) do { 5384 s1 += *buf++; 5385 s2 += s1; 5386 } while (--k); 5387 s1 %= BASE; 5388 s2 %= BASE; 5389 } 5390 return (s2 << 16) | s1; 5391} 5392/* --- adler32.c */ 5393 5394#ifdef _KERNEL 5395static int 5396zlib_modevent(module_t mod, int type, void *unused) 5397{ 5398 switch (type) { 5399 case MOD_LOAD: 5400 return 0; 5401 case MOD_UNLOAD: 5402 return 0; 5403 } 5404 return EINVAL; 5405} 5406 5407static moduledata_t zlib_mod = { 5408 "zlib", 5409 zlib_modevent, 5410 0 5411}; 5412DECLARE_MODULE(zlib, zlib_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST); 5413MODULE_VERSION(zlib, 1); 5414#endif /* _KERNEL */ 5415