1/* 2 Copyright (c) 1990-2002 Info-ZIP. All rights reserved. 3 4 See the accompanying file LICENSE, version 2000-Apr-09 or later 5 (the contents of which are also included in unzip.h) for terms of use. 6 If, for some reason, all these files are missing, the Info-ZIP license 7 also may be found at: ftp://ftp.info-zip.org/pub/infozip/license.html 8*/ 9/* inflate.c -- by Mark Adler 10 version c17a, 04 Feb 2001 */ 11 12 13/* Copyright history: 14 - Starting with UnZip 5.41 of 16-April-2000, this source file 15 is covered by the Info-Zip LICENSE cited above. 16 - Prior versions of this source file, found in UnZip source packages 17 up to UnZip 5.40, were put in the public domain. 18 The original copyright note by Mark Adler was: 19 "You can do whatever you like with this source file, 20 though I would prefer that if you modify it and 21 redistribute it that you include comments to that effect 22 with your name and the date. Thank you." 23 24 History: 25 vers date who what 26 ---- --------- -------------- ------------------------------------ 27 a ~~ Feb 92 M. Adler used full (large, one-step) lookup table 28 b1 21 Mar 92 M. Adler first version with partial lookup tables 29 b2 21 Mar 92 M. Adler fixed bug in fixed-code blocks 30 b3 22 Mar 92 M. Adler sped up match copies, cleaned up some 31 b4 25 Mar 92 M. Adler added prototypes; removed window[] (now 32 is the responsibility of unzip.h--also 33 changed name to slide[]), so needs diffs 34 for unzip.c and unzip.h (this allows 35 compiling in the small model on MSDOS); 36 fixed cast of q in huft_build(); 37 b5 26 Mar 92 M. Adler got rid of unintended macro recursion. 38 b6 27 Mar 92 M. Adler got rid of nextbyte() routine. fixed 39 bug in inflate_fixed(). 40 c1 30 Mar 92 M. Adler removed lbits, dbits environment variables. 41 changed BMAX to 16 for explode. Removed 42 OUTB usage, and replaced it with flush()-- 43 this was a 20% speed improvement! Added 44 an explode.c (to replace unimplod.c) that 45 uses the huft routines here. Removed 46 register union. 47 c2 4 Apr 92 M. Adler fixed bug for file sizes a multiple of 32k. 48 c3 10 Apr 92 M. Adler reduced memory of code tables made by 49 huft_build significantly (factor of two to 50 three). 51 c4 15 Apr 92 M. Adler added NOMEMCPY do kill use of memcpy(). 52 worked around a Turbo C optimization bug. 53 c5 21 Apr 92 M. Adler added the WSIZE #define to allow reducing 54 the 32K window size for specialized 55 applications. 56 c6 31 May 92 M. Adler added some typecasts to eliminate warnings 57 c7 27 Jun 92 G. Roelofs added some more typecasts (444: MSC bug). 58 c8 5 Oct 92 J-l. Gailly added ifdef'd code to deal with PKZIP bug. 59 c9 9 Oct 92 M. Adler removed a memory error message (~line 416). 60 c10 17 Oct 92 G. Roelofs changed ULONG/UWORD/byte to ulg/ush/uch, 61 removed old inflate, renamed inflate_entry 62 to inflate, added Mark's fix to a comment. 63 c10.5 14 Dec 92 M. Adler fix up error messages for incomplete trees. 64 c11 2 Jan 93 M. Adler fixed bug in detection of incomplete 65 tables, and removed assumption that EOB is 66 the longest code (bad assumption). 67 c12 3 Jan 93 M. Adler make tables for fixed blocks only once. 68 c13 5 Jan 93 M. Adler allow all zero length codes (pkzip 2.04c 69 outputs one zero length code for an empty 70 distance tree). 71 c14 12 Mar 93 M. Adler made inflate.c standalone with the 72 introduction of inflate.h. 73 c14b 16 Jul 93 G. Roelofs added (unsigned) typecast to w at 470. 74 c14c 19 Jul 93 J. Bush changed v[N_MAX], l[288], ll[28x+3x] arrays 75 to static for Amiga. 76 c14d 13 Aug 93 J-l. Gailly de-complicatified Mark's c[*p++]++ thing. 77 c14e 8 Oct 93 G. Roelofs changed memset() to memzero(). 78 c14f 22 Oct 93 G. Roelofs renamed quietflg to qflag; made Trace() 79 conditional; added inflate_free(). 80 c14g 28 Oct 93 G. Roelofs changed l/(lx+1) macro to pointer (Cray bug) 81 c14h 7 Dec 93 C. Ghisler huft_build() optimizations. 82 c14i 9 Jan 94 A. Verheijen set fixed_t{d,l} to NULL after freeing; 83 G. Roelofs check NEXTBYTE macro for EOF. 84 c14j 23 Jan 94 G. Roelofs removed Ghisler "optimizations"; ifdef'd 85 EOF check. 86 c14k 27 Feb 94 G. Roelofs added some typecasts to avoid warnings. 87 c14l 9 Apr 94 G. Roelofs fixed split comments on preprocessor lines 88 to avoid bug in Encore compiler. 89 c14m 7 Jul 94 P. Kienitz modified to allow assembler version of 90 inflate_codes() (define ASM_INFLATECODES) 91 c14n 22 Jul 94 G. Roelofs changed fprintf to macro for DLL versions 92 c14o 23 Aug 94 C. Spieler added a newline to a debug statement; 93 G. Roelofs added another typecast to avoid MSC warning 94 c14p 4 Oct 94 G. Roelofs added (voidp *) cast to free() argument 95 c14q 30 Oct 94 G. Roelofs changed fprintf macro to MESSAGE() 96 c14r 1 Nov 94 G. Roelofs fixed possible redefinition of CHECK_EOF 97 c14s 7 May 95 S. Maxwell OS/2 DLL globals stuff incorporated; 98 P. Kienitz "fixed" ASM_INFLATECODES macro/prototype 99 c14t 18 Aug 95 G. Roelofs added UZinflate() to use zlib functions; 100 changed voidp to zvoid; moved huft_build() 101 and huft_free() to end of file 102 c14u 1 Oct 95 G. Roelofs moved G into definition of MESSAGE macro 103 c14v 8 Nov 95 P. Kienitz changed ASM_INFLATECODES to use a regular 104 call with __G__ instead of a macro 105 c15 3 Aug 96 M. Adler fixed bomb-bug on random input data (Adobe) 106 c15b 24 Aug 96 M. Adler more fixes for random input data 107 c15c 28 Mar 97 G. Roelofs changed USE_ZLIB fatal exit code from 108 PK_MEM2 to PK_MEM3 109 c16 20 Apr 97 J. Altman added memzero(v[]) in huft_build() 110 c16b 29 Mar 98 C. Spieler modified DLL code for slide redirection 111 c16c 04 Apr 99 C. Spieler fixed memory leaks when processing gets 112 stopped because of input data errors 113 c16d 05 Jul 99 C. Spieler take care of FLUSH() return values and 114 stop processing in case of errors 115 c17 31 Dec 00 C. Spieler added preliminary support for Deflate64 116 c17a 04 Feb 01 C. Spieler complete integration of Deflate64 support 117 c17b 16 Feb 02 C. Spieler changed type of "extra bits" arrays and 118 corresponding huft_buid() parameter e from 119 ush into uch, to save space 120 */ 121 122 123/* 124 Inflate deflated (PKZIP's method 8 compressed) data. The compression 125 method searches for as much of the current string of bytes (up to a 126 length of 258) in the previous 32K bytes. If it doesn't find any 127 matches (of at least length 3), it codes the next byte. Otherwise, it 128 codes the length of the matched string and its distance backwards from 129 the current position. There is a single Huffman code that codes both 130 single bytes (called "literals") and match lengths. A second Huffman 131 code codes the distance information, which follows a length code. Each 132 length or distance code actually represents a base value and a number 133 of "extra" (sometimes zero) bits to get to add to the base value. At 134 the end of each deflated block is a special end-of-block (EOB) literal/ 135 length code. The decoding process is basically: get a literal/length 136 code; if EOB then done; if a literal, emit the decoded byte; if a 137 length then get the distance and emit the referred-to bytes from the 138 sliding window of previously emitted data. 139 140 There are (currently) three kinds of inflate blocks: stored, fixed, and 141 dynamic. The compressor outputs a chunk of data at a time and decides 142 which method to use on a chunk-by-chunk basis. A chunk might typically 143 be 32K to 64K, uncompressed. If the chunk is uncompressible, then the 144 "stored" method is used. In this case, the bytes are simply stored as 145 is, eight bits per byte, with none of the above coding. The bytes are 146 preceded by a count, since there is no longer an EOB code. 147 148 If the data are compressible, then either the fixed or dynamic methods 149 are used. In the dynamic method, the compressed data are preceded by 150 an encoding of the literal/length and distance Huffman codes that are 151 to be used to decode this block. The representation is itself Huffman 152 coded, and so is preceded by a description of that code. These code 153 descriptions take up a little space, and so for small blocks, there is 154 a predefined set of codes, called the fixed codes. The fixed method is 155 used if the block ends up smaller that way (usually for quite small 156 chunks); otherwise the dynamic method is used. In the latter case, the 157 codes are customized to the probabilities in the current block and so 158 can code it much better than the pre-determined fixed codes can. 159 160 The Huffman codes themselves are decoded using a multi-level table 161 lookup, in order to maximize the speed of decoding plus the speed of 162 building the decoding tables. See the comments below that precede the 163 lbits and dbits tuning parameters. 164 165 GRR: return values(?) 166 0 OK 167 1 incomplete table 168 2 bad input 169 3 not enough memory 170 the following return codes are passed through from FLUSH() errors 171 50 (PK_DISK) "overflow of output space" 172 80 (IZ_CTRLC) "canceled by user's request" 173 */ 174 175 176/* 177 Notes beyond the 1.93a appnote.txt: 178 179 1. Distance pointers never point before the beginning of the output 180 stream. 181 2. Distance pointers can point back across blocks, up to 32k away. 182 3. There is an implied maximum of 7 bits for the bit length table and 183 15 bits for the actual data. 184 4. If only one code exists, then it is encoded using one bit. (Zero 185 would be more efficient, but perhaps a little confusing.) If two 186 codes exist, they are coded using one bit each (0 and 1). 187 5. There is no way of sending zero distance codes--a dummy must be 188 sent if there are none. (History: a pre 2.0 version of PKZIP would 189 store blocks with no distance codes, but this was discovered to be 190 too harsh a criterion.) Valid only for 1.93a. 2.04c does allow 191 zero distance codes, which is sent as one code of zero bits in 192 length. 193 6. There are up to 286 literal/length codes. Code 256 represents the 194 end-of-block. Note however that the static length tree defines 195 288 codes just to fill out the Huffman codes. Codes 286 and 287 196 cannot be used though, since there is no length base or extra bits 197 defined for them. Similarily, there are up to 30 distance codes. 198 However, static trees define 32 codes (all 5 bits) to fill out the 199 Huffman codes, but the last two had better not show up in the data. 200 7. Unzip can check dynamic Huffman blocks for complete code sets. 201 The exception is that a single code would not be complete (see #4). 202 8. The five bits following the block type is really the number of 203 literal codes sent minus 257. 204 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits 205 (1+6+6). Therefore, to output three times the length, you output 206 three codes (1+1+1), whereas to output four times the same length, 207 you only need two codes (1+3). Hmm. 208 10. In the tree reconstruction algorithm, Code = Code + Increment 209 only if BitLength(i) is not zero. (Pretty obvious.) 210 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19) 211 12. Note: length code 284 can represent 227-258, but length code 285 212 really is 258. The last length deserves its own, short code 213 since it gets used a lot in very redundant files. The length 214 258 is special since 258 - 3 (the min match length) is 255. 215 13. The literal/length and distance code bit lengths are read as a 216 single stream of lengths. It is possible (and advantageous) for 217 a repeat code (16, 17, or 18) to go across the boundary between 218 the two sets of lengths. 219 14. The Deflate64 (PKZIP method 9) variant of the compression algorithm 220 differs from "classic" deflate in the following 3 aspect: 221 a) The size of the sliding history window is expanded to 64 kByte. 222 b) The previously unused distance codes #30 and #31 code distances 223 from 32769 to 49152 and 49153 to 65536. Both codes take 14 bits 224 of extra data to determine the exact position in their 16 kByte 225 range. 226 c) The last lit/length code #285 gets a different meaning. Instead 227 of coding a fixed maximum match length of 258, it is used as a 228 "generic" match length code, capable of coding any length from 229 3 (min match length + 0) to 65538 (min match length + 65535). 230 This means that the length code #285 takes 16 bits (!) of uncoded 231 extra data, added to a fixed min length of 3. 232 Changes a) and b) would have been transparent for valid deflated 233 data, but change c) requires to switch decoder configurations between 234 Deflate and Deflate64 modes. 235 */ 236 237 238#define PKZIP_BUG_WORKAROUND /* PKZIP 1.93a problem--live with it */ 239 240/* 241 inflate.h must supply the uch slide[WSIZE] array, the zvoid typedef 242 (void if (void *) is accepted, else char) and the NEXTBYTE, 243 FLUSH() and memzero macros. If the window size is not 32K, it 244 should also define WSIZE. If INFMOD is defined, it can include 245 compiled functions to support the NEXTBYTE and/or FLUSH() macros. 246 There are defaults for NEXTBYTE and FLUSH() below for use as 247 examples of what those functions need to do. Normally, you would 248 also want FLUSH() to compute a crc on the data. inflate.h also 249 needs to provide these typedefs: 250 251 typedef unsigned char uch; 252 typedef unsigned short ush; 253 typedef unsigned long ulg; 254 255 This module uses the external functions malloc() and free() (and 256 probably memset() or bzero() in the memzero() macro). Their 257 prototypes are normally found in <string.h> and <stdlib.h>. 258 */ 259 260#define __INFLATE_C /* identifies this source module */ 261 262/* #define DEBUG */ 263#define INFMOD /* tell inflate.h to include code to be compiled */ 264#include "inflate.h" 265 266 267/* marker for "unused" huft code, and corresponding check macro */ 268#define INVALID_CODE 99 269#define IS_INVALID_CODE(c) ((c) == INVALID_CODE) 270 271#ifndef WSIZE /* default is 32K resp. 64K */ 272# ifdef USE_DEFLATE64 273# define WSIZE 65536L /* window size--must be a power of two, and */ 274# else /* at least 64K for PKZip's deflate64 method */ 275# define WSIZE 0x8000 /* window size--must be a power of two, and */ 276# endif /* at least 32K for zip's deflate method */ 277#endif 278 279/* some buffer counters must be capable of holding 64k for Deflate64 */ 280#if (defined(USE_DEFLATE64) && defined(INT_16BIT)) 281# define UINT_D64 ulg 282#else 283# define UINT_D64 unsigned 284#endif 285 286#if (defined(DLL) && !defined(NO_SLIDE_REDIR)) 287# define wsize G._wsize /* wsize is a variable */ 288#else 289# define wsize WSIZE /* wsize is a constant */ 290#endif 291 292 293#ifndef NEXTBYTE /* default is to simply get a byte from stdin */ 294# define NEXTBYTE getchar() 295#endif 296 297#ifndef MESSAGE /* only used twice, for fixed strings--NOT general-purpose */ 298# define MESSAGE(str,len,flag) fprintf(stderr,(char *)(str)) 299#endif 300 301#ifndef FLUSH /* default is to simply write the buffer to stdout */ 302# define FLUSH(n) \ 303 (((extent)fwrite(redirSlide, 1, (extent)(n), stdout) == (extent)(n)) ? \ 304 0 : PKDISK) 305#endif 306/* Warning: the fwrite above might not work on 16-bit compilers, since 307 0x8000 might be interpreted as -32,768 by the library function. When 308 support for Deflate64 is enabled, the window size is 64K and the 309 simple fwrite statement is definitely broken for 16-bit compilers. */ 310 311#ifndef Trace 312# ifdef DEBUG 313# define Trace(x) fprintf x 314# else 315# define Trace(x) 316# endif 317#endif 318 319 320/*---------------------------------------------------------------------------*/ 321#ifdef USE_ZLIB 322 323 324/* 325 GRR: return values for both original inflate() and UZinflate() 326 0 OK 327 1 incomplete table(?) 328 2 bad input 329 3 not enough memory 330 */ 331 332/**************************/ 333/* Function UZinflate() */ 334/**************************/ 335 336int UZinflate(__G__ is_defl64) 337 __GDEF 338 int is_defl64; 339/* decompress an inflated entry using the zlib routines */ 340{ 341 int retval = 0; /* return code: 0 = "no error" */ 342 int err=Z_OK; 343 344#if (defined(DLL) && !defined(NO_SLIDE_REDIR)) 345 if (G.redirect_slide) 346 wsize = G.redirect_size, redirSlide = G.redirect_buffer; 347 else 348 wsize = WSIZE, redirSlide = slide; 349#endif 350 351 G.dstrm.next_out = redirSlide; 352 G.dstrm.avail_out = wsize; 353 354 G.dstrm.next_in = G.inptr; 355 G.dstrm.avail_in = G.incnt; 356 357 if (!G.inflInit) { 358 unsigned i; 359 int windowBits; 360 361 /* only need to test this stuff once */ 362 if (zlib_version[0] != ZLIB_VERSION[0]) { 363 Info(slide, 0x21, ((char *)slide, 364 "error: incompatible zlib version (expected %s, found %s)\n", 365 ZLIB_VERSION, zlib_version)); 366 return 3; 367 } else if (strcmp(zlib_version, ZLIB_VERSION) != 0) 368 Info(slide, 0x21, ((char *)slide, 369 "warning: different zlib version (expected %s, using %s)\n", 370 ZLIB_VERSION, zlib_version)); 371 372 /* windowBits = log2(wsize) */ 373 for (i = (unsigned)wsize, windowBits = 0; 374 !(i & 1); i >>= 1, ++windowBits); 375 if ((unsigned)windowBits > (unsigned)15) 376 windowBits = 15; 377 else if (windowBits < 8) 378 windowBits = 8; 379 380 G.dstrm.zalloc = (alloc_func)Z_NULL; 381 G.dstrm.zfree = (free_func)Z_NULL; 382 383 Trace((stderr, "initializing inflate()\n")); 384 err = inflateInit2(&G.dstrm, -windowBits); 385 386 if (err == Z_MEM_ERROR) 387 return 3; 388 else if (err != Z_OK) 389 Trace((stderr, "oops! (inflateInit2() err = %d)\n", err)); 390 G.inflInit = 1; 391 } 392 393#ifdef FUNZIP 394 while (err != Z_STREAM_END) { 395#else /* !FUNZIP */ 396 while (G.csize > 0) { 397 Trace((stderr, "first loop: G.csize = %ld\n", G.csize)); 398#endif /* ?FUNZIP */ 399 while (G.dstrm.avail_out > 0) { 400 err = inflate(&G.dstrm, Z_PARTIAL_FLUSH); 401 402 if (err == Z_DATA_ERROR) { 403 retval = 2; goto uzinflate_cleanup_exit; 404 } else if (err == Z_MEM_ERROR) { 405 retval = 3; goto uzinflate_cleanup_exit; 406 } else if (err != Z_OK && err != Z_STREAM_END) 407 Trace((stderr, "oops! (inflate(first loop) err = %d)\n", err)); 408 409#ifdef FUNZIP 410 if (err == Z_STREAM_END) /* "END-of-entry-condition" ? */ 411#else /* !FUNZIP */ 412 if (G.csize <= 0L) /* "END-of-entry-condition" ? */ 413#endif /* ?FUNZIP */ 414 break; 415 416 if (G.dstrm.avail_in <= 0) { 417 if (fillinbuf(__G) == 0) { 418 /* no "END-condition" yet, but no more data */ 419 retval = 2; goto uzinflate_cleanup_exit; 420 } 421 422 G.dstrm.next_in = G.inptr; 423 G.dstrm.avail_in = G.incnt; 424 } 425 Trace((stderr, " avail_in = %d\n", G.dstrm.avail_in)); 426 } 427 /* flush slide[] */ 428 if ((retval = FLUSH(wsize - G.dstrm.avail_out)) != 0) 429 goto uzinflate_cleanup_exit; 430 Trace((stderr, "inside loop: flushing %ld bytes (ptr diff = %ld)\n", 431 (long)(wsize - G.dstrm.avail_out), 432 (long)(G.dstrm.next_out-(Bytef *)redirSlide))); 433 G.dstrm.next_out = redirSlide; 434 G.dstrm.avail_out = wsize; 435 } 436 437 /* no more input, so loop until we have all output */ 438 Trace((stderr, "beginning final loop: err = %d\n", err)); 439 while (err != Z_STREAM_END) { 440 err = inflate(&G.dstrm, Z_PARTIAL_FLUSH); 441 if (err == Z_DATA_ERROR) { 442 retval = 2; goto uzinflate_cleanup_exit; 443 } else if (err == Z_MEM_ERROR) { 444 retval = 3; goto uzinflate_cleanup_exit; 445 } else if (err == Z_BUF_ERROR) { /* DEBUG */ 446 Trace((stderr, 447 "zlib inflate() did not detect stream end (%s, %s)\n", 448 G.zipfn, G.filename)); 449 break; 450 } else if (err != Z_OK && err != Z_STREAM_END) { 451 Trace((stderr, "oops! (inflate(final loop) err = %d)\n", err)); 452 DESTROYGLOBALS(); 453 EXIT(PK_MEM3); 454 } 455 /* final flush of slide[] */ 456 if ((retval = FLUSH(wsize - G.dstrm.avail_out)) != 0) 457 goto uzinflate_cleanup_exit; 458 Trace((stderr, "final loop: flushing %ld bytes (ptr diff = %ld)\n", 459 (long)(wsize - G.dstrm.avail_out), 460 (long)(G.dstrm.next_out-(Bytef *)redirSlide))); 461 G.dstrm.next_out = redirSlide; 462 G.dstrm.avail_out = wsize; 463 } 464 Trace((stderr, "total in = %ld, total out = %ld\n", G.dstrm.total_in, 465 G.dstrm.total_out)); 466 467 G.inptr = (uch *)G.dstrm.next_in; 468 G.incnt = (G.inbuf + INBUFSIZ) - G.inptr; /* reset for other routines */ 469 470uzinflate_cleanup_exit: 471 err = inflateReset(&G.dstrm); 472 if (err != Z_OK) 473 Trace((stderr, "oops! (inflateReset() err = %d)\n", err)); 474 475 return retval; 476} 477 478 479/*---------------------------------------------------------------------------*/ 480#else /* !USE_ZLIB */ 481 482 483/* Function prototypes */ 484#ifndef OF 485# ifdef __STDC__ 486# define OF(a) a 487# else 488# define OF(a) () 489# endif 490#endif /* !OF */ 491int inflate_codes OF((__GPRO__ struct huft *tl, struct huft *td, 492 int bl, int bd)); 493static int inflate_stored OF((__GPRO)); 494static int inflate_fixed OF((__GPRO)); 495static int inflate_dynamic OF((__GPRO)); 496static int inflate_block OF((__GPRO__ int *e)); 497 498 499/* The inflate algorithm uses a sliding 32K byte window on the uncompressed 500 stream to find repeated byte strings. This is implemented here as a 501 circular buffer. The index is updated simply by incrementing and then 502 and'ing with 0x7fff (32K-1). */ 503/* It is left to other modules to supply the 32K area. It is assumed 504 to be usable as if it were declared "uch slide[32768];" or as just 505 "uch *slide;" and then malloc'ed in the latter case. The definition 506 must be in unzip.h, included above. */ 507 508 509/* unsigned wp; moved to globals.h */ /* current position in slide */ 510 511/* Tables for deflate from PKZIP's appnote.txt. */ 512/* - Order of the bit length code lengths */ 513static ZCONST unsigned border[] = { 514 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; 515 516/* - Copy lengths for literal codes 257..285 */ 517#ifdef USE_DEFLATE64 518static ZCONST ush cplens64[] = { 519 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, 520 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 3, 0, 0}; 521 /* For Deflate64, the code 285 is defined differently. */ 522#else 523# define cplens32 cplens 524#endif 525static ZCONST ush cplens32[] = { 526 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, 527 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0}; 528 /* note: see note #13 above about the 258 in this list. */ 529/* - Extra bits for literal codes 257..285 */ 530#ifdef USE_DEFLATE64 531static ZCONST uch cplext64[] = { 532 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 533 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 16, INVALID_CODE, INVALID_CODE}; 534#else 535# define cplext32 cplext 536#endif 537static ZCONST uch cplext32[] = { 538 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 539 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, INVALID_CODE, INVALID_CODE}; 540 541/* - Copy offsets for distance codes 0..29 (0..31 for Deflate64) */ 542static ZCONST ush cpdist[] = { 543 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, 544 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145, 545#if (defined(USE_DEFLATE64) || defined(PKZIP_BUG_WORKAROUND)) 546 8193, 12289, 16385, 24577, 32769, 49153}; 547#else 548 8193, 12289, 16385, 24577}; 549#endif 550 551/* - Extra bits for distance codes 0..29 (0..31 for Deflate64) */ 552#ifdef USE_DEFLATE64 553static ZCONST uch cpdext64[] = { 554 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 555 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 556 12, 12, 13, 13, 14, 14}; 557#else 558# define cpdext32 cpdext 559#endif 560static ZCONST uch cpdext32[] = { 561 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 562 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 563#ifdef PKZIP_BUG_WORKAROUND 564 12, 12, 13, 13, INVALID_CODE, INVALID_CODE}; 565#else 566 12, 12, 13, 13}; 567#endif 568 569#ifdef PKZIP_BUG_WORKAROUND 570# define MAXLITLENS 288 571#else 572# define MAXLITLENS 286 573#endif 574#if (defined(USE_DEFLATE64) || defined(PKZIP_BUG_WORKAROUND)) 575# define MAXDISTS 32 576#else 577# define MAXDISTS 30 578#endif 579 580 581/* moved to consts.h (included in unzip.c), resp. funzip.c */ 582#if 0 583/* And'ing with mask_bits[n] masks the lower n bits */ 584ZCONST ush near mask_bits[] = { 585 0x0000, 586 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff, 587 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff 588}; 589#endif /* 0 */ 590 591 592/* Macros for inflate() bit peeking and grabbing. 593 The usage is: 594 595 NEEDBITS(j) 596 x = b & mask_bits[j]; 597 DUMPBITS(j) 598 599 where NEEDBITS makes sure that b has at least j bits in it, and 600 DUMPBITS removes the bits from b. The macros use the variable k 601 for the number of bits in b. Normally, b and k are register 602 variables for speed and are initialized at the begining of a 603 routine that uses these macros from a global bit buffer and count. 604 605 In order to not ask for more bits than there are in the compressed 606 stream, the Huffman tables are constructed to only ask for just 607 enough bits to make up the end-of-block code (value 256). Then no 608 bytes need to be "returned" to the buffer at the end of the last 609 block. See the huft_build() routine. 610 */ 611 612/* These have been moved to globals.h */ 613#if 0 614ulg bb; /* bit buffer */ 615unsigned bk; /* bits in bit buffer */ 616#endif 617 618#ifndef CHECK_EOF 619# define CHECK_EOF /* default as of 5.13/5.2 */ 620#endif 621 622#ifndef CHECK_EOF 623# define NEEDBITS(n) {while(k<(n)){b|=((ulg)NEXTBYTE)<<k;k+=8;}} 624#else 625# define NEEDBITS(n) {while(k<(n)){int c=NEXTBYTE;\ 626 if(c==EOF){retval=1;goto cleanup_and_exit;}\ 627 b|=((ulg)c)<<k;k+=8;}} 628#endif 629 630#define DUMPBITS(n) {b>>=(n);k-=(n);} 631 632 633/* 634 Huffman code decoding is performed using a multi-level table lookup. 635 The fastest way to decode is to simply build a lookup table whose 636 size is determined by the longest code. However, the time it takes 637 to build this table can also be a factor if the data being decoded 638 are not very long. The most common codes are necessarily the 639 shortest codes, so those codes dominate the decoding time, and hence 640 the speed. The idea is you can have a shorter table that decodes the 641 shorter, more probable codes, and then point to subsidiary tables for 642 the longer codes. The time it costs to decode the longer codes is 643 then traded against the time it takes to make longer tables. 644 645 This results of this trade are in the variables lbits and dbits 646 below. lbits is the number of bits the first level table for literal/ 647 length codes can decode in one step, and dbits is the same thing for 648 the distance codes. Subsequent tables are also less than or equal to 649 those sizes. These values may be adjusted either when all of the 650 codes are shorter than that, in which case the longest code length in 651 bits is used, or when the shortest code is *longer* than the requested 652 table size, in which case the length of the shortest code in bits is 653 used. 654 655 There are two different values for the two tables, since they code a 656 different number of possibilities each. The literal/length table 657 codes 286 possible values, or in a flat code, a little over eight 658 bits. The distance table codes 30 possible values, or a little less 659 than five bits, flat. The optimum values for speed end up being 660 about one bit more than those, so lbits is 8+1 and dbits is 5+1. 661 The optimum values may differ though from machine to machine, and 662 possibly even between compilers. Your mileage may vary. 663 */ 664 665 666static ZCONST int lbits = 9; /* bits in base literal/length lookup table */ 667static ZCONST int dbits = 6; /* bits in base distance lookup table */ 668 669 670#ifndef ASM_INFLATECODES 671 672int inflate_codes(__G__ tl, td, bl, bd) 673 __GDEF 674struct huft *tl, *td; /* literal/length and distance decoder tables */ 675int bl, bd; /* number of bits decoded by tl[] and td[] */ 676/* inflate (decompress) the codes in a deflated (compressed) block. 677 Return an error code or zero if it all goes ok. */ 678{ 679 register unsigned e; /* table entry flag/number of extra bits */ 680 unsigned d; /* index for copy */ 681 UINT_D64 n; /* length for copy (deflate64: might be 64k+2) */ 682 UINT_D64 w; /* current window position (deflate64: up to 64k) */ 683 struct huft *t; /* pointer to table entry */ 684 unsigned ml, md; /* masks for bl and bd bits */ 685 register ulg b; /* bit buffer */ 686 register unsigned k; /* number of bits in bit buffer */ 687 int retval = 0; /* error code returned: initialized to "no error" */ 688 689 690 /* make local copies of globals */ 691 b = G.bb; /* initialize bit buffer */ 692 k = G.bk; 693 w = G.wp; /* initialize window position */ 694 695 696 /* inflate the coded data */ 697 ml = mask_bits[bl]; /* precompute masks for speed */ 698 md = mask_bits[bd]; 699 while (1) /* do until end of block */ 700 { 701 NEEDBITS((unsigned)bl) 702 t = tl + ((unsigned)b & ml); 703 while (1) { 704 DUMPBITS(t->b) 705 706 if ((e = t->e) == 32) /* then it's a literal */ 707 { 708 redirSlide[w++] = (uch)t->v.n; 709 if (w == wsize) 710 { 711 if ((retval = FLUSH(w)) != 0) goto cleanup_and_exit; 712 w = 0; 713 } 714 break; 715 } 716 717 if (e < 31) /* then it's a length */ 718 { 719 /* get length of block to copy */ 720 NEEDBITS(e) 721 n = t->v.n + ((unsigned)b & mask_bits[e]); 722 DUMPBITS(e) 723 724 /* decode distance of block to copy */ 725 NEEDBITS((unsigned)bd) 726 t = td + ((unsigned)b & md); 727 while (1) { 728 DUMPBITS(t->b) 729 if ((e = t->e) < 32) 730 break; 731 if (IS_INVALID_CODE(e)) 732 return 1; 733 e &= 31; 734 NEEDBITS(e) 735 t = t->v.t + ((unsigned)b & mask_bits[e]); 736 } 737 NEEDBITS(e) 738 d = (unsigned)w - t->v.n - ((unsigned)b & mask_bits[e]); 739 DUMPBITS(e) 740 741 /* do the copy */ 742 do { 743#if (defined(DLL) && !defined(NO_SLIDE_REDIR)) 744 if (G.redirect_slide) { 745 /* &= w/ wsize unnecessary & wrong if redirect */ 746 if ((UINT_D64)d >= wsize) 747 return 1; /* invalid compressed data */ 748 e = (unsigned)(wsize - (d > (unsigned)w ? (UINT_D64)d : w)); 749 } 750 else 751#endif 752 e = (unsigned)(wsize - 753 ((d &= (unsigned)(wsize-1)) > (unsigned)w ? 754 (UINT_D64)d : w)); 755 if ((UINT_D64)e > n) e = (unsigned)n; 756 n -= e; 757#ifndef NOMEMCPY 758 if ((unsigned)w - d >= e) 759 /* (this test assumes unsigned comparison) */ 760 { 761 memcpy(redirSlide + (unsigned)w, redirSlide + d, e); 762 w += e; 763 d += e; 764 } 765 else /* do it slowly to avoid memcpy() overlap */ 766#endif /* !NOMEMCPY */ 767 do { 768 redirSlide[w++] = redirSlide[d++]; 769 } while (--e); 770 if (w == wsize) 771 { 772 if ((retval = FLUSH(w)) != 0) goto cleanup_and_exit; 773 w = 0; 774 } 775 } while (n); 776 break; 777 } 778 779 if (e == 31) /* it's the EOB signal */ 780 { 781 /* sorry for this goto, but we have to exit two loops at once */ 782 goto cleanup_decode; 783 } 784 785 if (IS_INVALID_CODE(e)) 786 return 1; 787 788 e &= 31; 789 NEEDBITS(e) 790 t = t->v.t + ((unsigned)b & mask_bits[e]); 791 } 792 } 793cleanup_decode: 794 795 /* restore the globals from the locals */ 796 G.wp = (unsigned)w; /* restore global window pointer */ 797 G.bb = b; /* restore global bit buffer */ 798 G.bk = k; 799 800 801cleanup_and_exit: 802 /* done */ 803 return retval; 804} 805 806#endif /* ASM_INFLATECODES */ 807 808 809 810static int inflate_stored(__G) 811 __GDEF 812/* "decompress" an inflated type 0 (stored) block. */ 813{ 814 UINT_D64 w; /* current window position (deflate64: up to 64k!) */ 815 unsigned n; /* number of bytes in block */ 816 register ulg b; /* bit buffer */ 817 register unsigned k; /* number of bits in bit buffer */ 818 int retval = 0; /* error code returned: initialized to "no error" */ 819 820 821 /* make local copies of globals */ 822 Trace((stderr, "\nstored block")); 823 b = G.bb; /* initialize bit buffer */ 824 k = G.bk; 825 w = G.wp; /* initialize window position */ 826 827 828 /* go to byte boundary */ 829 n = k & 7; 830 DUMPBITS(n); 831 832 833 /* get the length and its complement */ 834 NEEDBITS(16) 835 n = ((unsigned)b & 0xffff); 836 DUMPBITS(16) 837 NEEDBITS(16) 838 if (n != (unsigned)((~b) & 0xffff)) 839 return 1; /* error in compressed data */ 840 DUMPBITS(16) 841 842 843 /* read and output the compressed data */ 844 while (n--) 845 { 846 NEEDBITS(8) 847 redirSlide[w++] = (uch)b; 848 if (w == wsize) 849 { 850 if ((retval = FLUSH(w)) != 0) goto cleanup_and_exit; 851 w = 0; 852 } 853 DUMPBITS(8) 854 } 855 856 857 /* restore the globals from the locals */ 858 G.wp = (unsigned)w; /* restore global window pointer */ 859 G.bb = b; /* restore global bit buffer */ 860 G.bk = k; 861 862cleanup_and_exit: 863 return retval; 864} 865 866 867/* Globals for literal tables (built once) */ 868/* Moved to globals.h */ 869#if 0 870struct huft *fixed_tl = (struct huft *)NULL; 871struct huft *fixed_td; 872int fixed_bl, fixed_bd; 873#endif 874 875static int inflate_fixed(__G) 876 __GDEF 877/* decompress an inflated type 1 (fixed Huffman codes) block. We should 878 either replace this with a custom decoder, or at least precompute the 879 Huffman tables. */ 880{ 881 /* if first time, set up tables for fixed blocks */ 882 Trace((stderr, "\nliteral block")); 883 if (G.fixed_tl == (struct huft *)NULL) 884 { 885 int i; /* temporary variable */ 886 unsigned l[288]; /* length list for huft_build */ 887 888 /* literal table */ 889 for (i = 0; i < 144; i++) 890 l[i] = 8; 891 for (; i < 256; i++) 892 l[i] = 9; 893 for (; i < 280; i++) 894 l[i] = 7; 895 for (; i < 288; i++) /* make a complete, but wrong code set */ 896 l[i] = 8; 897 G.fixed_bl = 7; 898#ifdef USE_DEFLATE64 899 if ((i = huft_build(__G__ l, 288, 257, G.cplens, G.cplext, 900 &G.fixed_tl, &G.fixed_bl)) != 0) 901#else 902 if ((i = huft_build(__G__ l, 288, 257, cplens, cplext, 903 &G.fixed_tl, &G.fixed_bl)) != 0) 904#endif 905 { 906 G.fixed_tl = (struct huft *)NULL; 907 return i; 908 } 909 910 /* distance table */ 911 for (i = 0; i < MAXDISTS; i++) /* make an incomplete code set */ 912 l[i] = 5; 913 G.fixed_bd = 5; 914#ifdef USE_DEFLATE64 915 if ((i = huft_build(__G__ l, MAXDISTS, 0, cpdist, G.cpdext, 916 &G.fixed_td, &G.fixed_bd)) > 1) 917#else 918 if ((i = huft_build(__G__ l, MAXDISTS, 0, cpdist, cpdext, 919 &G.fixed_td, &G.fixed_bd)) > 1) 920#endif 921 { 922 huft_free(G.fixed_tl); 923 G.fixed_td = G.fixed_tl = (struct huft *)NULL; 924 return i; 925 } 926 } 927 928 /* decompress until an end-of-block code */ 929 return inflate_codes(__G__ G.fixed_tl, G.fixed_td, 930 G.fixed_bl, G.fixed_bd); 931} 932 933 934 935static int inflate_dynamic(__G) 936 __GDEF 937/* decompress an inflated type 2 (dynamic Huffman codes) block. */ 938{ 939 int i; /* temporary variables */ 940 unsigned j; 941 unsigned l; /* last length */ 942 unsigned m; /* mask for bit lengths table */ 943 unsigned n; /* number of lengths to get */ 944 struct huft *tl; /* literal/length code table */ 945 struct huft *td; /* distance code table */ 946 int bl; /* lookup bits for tl */ 947 int bd; /* lookup bits for td */ 948 unsigned nb; /* number of bit length codes */ 949 unsigned nl; /* number of literal/length codes */ 950 unsigned nd; /* number of distance codes */ 951 unsigned ll[MAXLITLENS+MAXDISTS]; /* lit./length and distance code lengths */ 952 register ulg b; /* bit buffer */ 953 register unsigned k; /* number of bits in bit buffer */ 954 int retval = 0; /* error code returned: initialized to "no error" */ 955 956 957 /* make local bit buffer */ 958 Trace((stderr, "\ndynamic block")); 959 b = G.bb; 960 k = G.bk; 961 962 963 /* read in table lengths */ 964 NEEDBITS(5) 965 nl = 257 + ((unsigned)b & 0x1f); /* number of literal/length codes */ 966 DUMPBITS(5) 967 NEEDBITS(5) 968 nd = 1 + ((unsigned)b & 0x1f); /* number of distance codes */ 969 DUMPBITS(5) 970 NEEDBITS(4) 971 nb = 4 + ((unsigned)b & 0xf); /* number of bit length codes */ 972 DUMPBITS(4) 973 if (nl > MAXLITLENS || nd > MAXDISTS) 974 return 1; /* bad lengths */ 975 976 977 /* read in bit-length-code lengths */ 978 for (j = 0; j < nb; j++) 979 { 980 NEEDBITS(3) 981 ll[border[j]] = (unsigned)b & 7; 982 DUMPBITS(3) 983 } 984 for (; j < 19; j++) 985 ll[border[j]] = 0; 986 987 988 /* build decoding table for trees--single level, 7 bit lookup */ 989 bl = 7; 990 retval = huft_build(__G__ ll, 19, 19, NULL, NULL, &tl, &bl); 991 if (bl == 0) /* no bit lengths */ 992 retval = 1; 993 if (retval) 994 { 995 if (retval == 1) 996 huft_free(tl); 997 return retval; /* incomplete code set */ 998 } 999 1000 1001 /* read in literal and distance code lengths */ 1002 n = nl + nd; 1003 m = mask_bits[bl]; 1004 i = l = 0; 1005 while ((unsigned)i < n) 1006 { 1007 NEEDBITS((unsigned)bl) 1008 j = (td = tl + ((unsigned)b & m))->b; 1009 DUMPBITS(j) 1010 j = td->v.n; 1011 if (j < 16) /* length of code in bits (0..15) */ 1012 ll[i++] = l = j; /* save last length in l */ 1013 else if (j == 16) /* repeat last length 3 to 6 times */ 1014 { 1015 NEEDBITS(2) 1016 j = 3 + ((unsigned)b & 3); 1017 DUMPBITS(2) 1018 if ((unsigned)i + j > n) 1019 return 1; 1020 while (j--) 1021 ll[i++] = l; 1022 } 1023 else if (j == 17) /* 3 to 10 zero length codes */ 1024 { 1025 NEEDBITS(3) 1026 j = 3 + ((unsigned)b & 7); 1027 DUMPBITS(3) 1028 if ((unsigned)i + j > n) 1029 return 1; 1030 while (j--) 1031 ll[i++] = 0; 1032 l = 0; 1033 } 1034 else /* j == 18: 11 to 138 zero length codes */ 1035 { 1036 NEEDBITS(7) 1037 j = 11 + ((unsigned)b & 0x7f); 1038 DUMPBITS(7) 1039 if ((unsigned)i + j > n) 1040 return 1; 1041 while (j--) 1042 ll[i++] = 0; 1043 l = 0; 1044 } 1045 } 1046 1047 1048 /* free decoding table for trees */ 1049 huft_free(tl); 1050 1051 1052 /* restore the global bit buffer */ 1053 G.bb = b; 1054 G.bk = k; 1055 1056 1057 /* build the decoding tables for literal/length and distance codes */ 1058 bl = lbits; 1059#ifdef USE_DEFLATE64 1060 retval = huft_build(__G__ ll, nl, 257, G.cplens, G.cplext, &tl, &bl); 1061#else 1062 retval = huft_build(__G__ ll, nl, 257, cplens, cplext, &tl, &bl); 1063#endif 1064 if (bl == 0) /* no literals or lengths */ 1065 retval = 1; 1066 if (retval) 1067 { 1068 if (retval == 1) { 1069 if (!uO.qflag) 1070 MESSAGE((uch *)"(incomplete l-tree) ", 21L, 1); 1071 huft_free(tl); 1072 } 1073 return retval; /* incomplete code set */ 1074 } 1075 bd = dbits; 1076#ifdef USE_DEFLATE64 1077 retval = huft_build(__G__ ll + nl, nd, 0, cpdist, G.cpdext, &td, &bd); 1078#else 1079 retval = huft_build(__G__ ll + nl, nd, 0, cpdist, cpdext, &td, &bd); 1080#endif 1081#ifdef PKZIP_BUG_WORKAROUND 1082 if (retval == 1) 1083 retval = 0; 1084#endif 1085 if (bd == 0 && nl > 257) /* lengths but no distances */ 1086 retval = 1; 1087 if (retval) 1088 { 1089 if (retval == 1) { 1090 if (!uO.qflag) 1091 MESSAGE((uch *)"(incomplete d-tree) ", 21L, 1); 1092 huft_free(td); 1093 } 1094 huft_free(tl); 1095 return retval; 1096 } 1097 1098 /* decompress until an end-of-block code */ 1099 retval = inflate_codes(__G__ tl, td, bl, bd); 1100 1101cleanup_and_exit: 1102 /* free the decoding tables, return */ 1103 huft_free(tl); 1104 huft_free(td); 1105 return retval; 1106} 1107 1108 1109 1110static int inflate_block(__G__ e) 1111 __GDEF 1112 int *e; /* last block flag */ 1113/* decompress an inflated block */ 1114{ 1115 unsigned t; /* block type */ 1116 register ulg b; /* bit buffer */ 1117 register unsigned k; /* number of bits in bit buffer */ 1118 int retval = 0; /* error code returned: initialized to "no error" */ 1119 1120 1121 /* make local bit buffer */ 1122 b = G.bb; 1123 k = G.bk; 1124 1125 1126 /* read in last block bit */ 1127 NEEDBITS(1) 1128 *e = (int)b & 1; 1129 DUMPBITS(1) 1130 1131 1132 /* read in block type */ 1133 NEEDBITS(2) 1134 t = (unsigned)b & 3; 1135 DUMPBITS(2) 1136 1137 1138 /* restore the global bit buffer */ 1139 G.bb = b; 1140 G.bk = k; 1141 1142 1143 /* inflate that block type */ 1144 if (t == 2) 1145 return inflate_dynamic(__G); 1146 if (t == 0) 1147 return inflate_stored(__G); 1148 if (t == 1) 1149 return inflate_fixed(__G); 1150 1151 1152 /* bad block type */ 1153 retval = 2; 1154 1155cleanup_and_exit: 1156 return retval; 1157} 1158 1159 1160 1161int inflate(__G__ is_defl64) 1162 __GDEF 1163 int is_defl64; 1164/* decompress an inflated entry */ 1165{ 1166 int e; /* last block flag */ 1167 int r; /* result code */ 1168#ifdef DEBUG 1169 unsigned h = 0; /* maximum struct huft's malloc'ed */ 1170#endif 1171 1172#if (defined(DLL) && !defined(NO_SLIDE_REDIR)) 1173 if (G.redirect_slide) 1174 wsize = G.redirect_size, redirSlide = G.redirect_buffer; 1175 else 1176 wsize = WSIZE, redirSlide = slide; /* how they're #defined if !DLL */ 1177#endif 1178 1179 /* initialize window, bit buffer */ 1180 G.wp = 0; 1181 G.bk = 0; 1182 G.bb = 0; 1183 1184#ifdef USE_DEFLATE64 1185 if (is_defl64) { 1186 G.cplens = cplens64; 1187 G.cplext = cplext64; 1188 G.cpdext = cpdext64; 1189 G.fixed_tl = G.fixed_tl64; 1190 G.fixed_bl = G.fixed_bl64; 1191 G.fixed_td = G.fixed_td64; 1192 G.fixed_bd = G.fixed_bd64; 1193 } else { 1194 G.cplens = cplens32; 1195 G.cplext = cplext32; 1196 G.cpdext = cpdext32; 1197 G.fixed_tl = G.fixed_tl32; 1198 G.fixed_bl = G.fixed_bl32; 1199 G.fixed_td = G.fixed_td32; 1200 G.fixed_bd = G.fixed_bd32; 1201 } 1202#else /* !USE_DEFLATE64 */ 1203 if (is_defl64) { 1204 /* This should not happen unless UnZip is built from object files 1205 * compiled with inconsistent option setting. Handle this by 1206 * returning with "bad input" error code. 1207 */ 1208 Trace((stderr, "\nThis inflate() cannot handle Deflate64!\n")); 1209 return 2; 1210 } 1211#endif /* ?USE_DEFLATE64 */ 1212 1213 /* decompress until the last block */ 1214 do { 1215#ifdef DEBUG 1216 G.hufts = 0; 1217#endif 1218 if ((r = inflate_block(__G__ &e)) != 0) 1219 return r; 1220#ifdef DEBUG 1221 if (G.hufts > h) 1222 h = G.hufts; 1223#endif 1224 } while (!e); 1225 1226 Trace((stderr, "\n%u bytes in Huffman tables (%u/entry)\n", 1227 h * (unsigned)sizeof(struct huft), (unsigned)sizeof(struct huft))); 1228 1229#ifdef USE_DEFLATE64 1230 if (is_defl64) { 1231 G.fixed_tl64 = G.fixed_tl; 1232 G.fixed_bl64 = G.fixed_bl; 1233 G.fixed_td64 = G.fixed_td; 1234 G.fixed_bd64 = G.fixed_bd; 1235 } else { 1236 G.fixed_tl32 = G.fixed_tl; 1237 G.fixed_bl32 = G.fixed_bl; 1238 G.fixed_td32 = G.fixed_td; 1239 G.fixed_bd32 = G.fixed_bd; 1240 } 1241#endif 1242 1243 /* flush out redirSlide and return (success, unless final FLUSH failed) */ 1244 return (FLUSH(G.wp)); 1245} 1246 1247 1248 1249int inflate_free(__G) 1250 __GDEF 1251{ 1252 if (G.fixed_tl != (struct huft *)NULL) 1253 { 1254 huft_free(G.fixed_td); 1255 huft_free(G.fixed_tl); 1256 G.fixed_td = G.fixed_tl = (struct huft *)NULL; 1257 } 1258 return 0; 1259} 1260 1261#endif /* ?USE_ZLIB */ 1262 1263 1264/* 1265 * GRR: moved huft_build() and huft_free() down here; used by explode() 1266 * and fUnZip regardless of whether USE_ZLIB defined or not 1267 */ 1268 1269 1270/* If BMAX needs to be larger than 16, then h and x[] should be ulg. */ 1271#define BMAX 16 /* maximum bit length of any code (16 for explode) */ 1272#define N_MAX 288 /* maximum number of codes in any set */ 1273 1274 1275int huft_build(__G__ b, n, s, d, e, t, m) 1276 __GDEF 1277 ZCONST unsigned *b; /* code lengths in bits (all assumed <= BMAX) */ 1278 unsigned n; /* number of codes (assumed <= N_MAX) */ 1279 unsigned s; /* number of simple-valued codes (0..s-1) */ 1280 ZCONST ush *d; /* list of base values for non-simple codes */ 1281 ZCONST uch *e; /* list of extra bits for non-simple codes */ 1282 struct huft **t; /* result: starting table */ 1283 int *m; /* maximum lookup bits, returns actual */ 1284/* Given a list of code lengths and a maximum table size, make a set of 1285 tables to decode that set of codes. Return zero on success, one if 1286 the given code set is incomplete (the tables are still built in this 1287 case), two if the input is invalid (all zero length codes or an 1288 oversubscribed set of lengths), and three if not enough memory. 1289 The code with value 256 is special, and the tables are constructed 1290 so that no bits beyond that code are fetched when that code is 1291 decoded. */ 1292{ 1293 unsigned a; /* counter for codes of length k */ 1294 unsigned c[BMAX+1]; /* bit length count table */ 1295 unsigned el; /* length of EOB code (value 256) */ 1296 unsigned f; /* i repeats in table every f entries */ 1297 int g; /* maximum code length */ 1298 int h; /* table level */ 1299 register unsigned i; /* counter, current code */ 1300 register unsigned j; /* counter */ 1301 register int k; /* number of bits in current code */ 1302 int lx[BMAX+1]; /* memory for l[-1..BMAX-1] */ 1303 int *l = lx+1; /* stack of bits per table */ 1304 register unsigned *p; /* pointer into c[], b[], or v[] */ 1305 register struct huft *q; /* points to current table */ 1306 struct huft r; /* table entry for structure assignment */ 1307 struct huft *u[BMAX]; /* table stack */ 1308 unsigned v[N_MAX]; /* values in order of bit length */ 1309 register int w; /* bits before this table == (l * h) */ 1310 unsigned x[BMAX+1]; /* bit offsets, then code stack */ 1311 unsigned *xp; /* pointer into x */ 1312 int y; /* number of dummy codes added */ 1313 unsigned z; /* number of entries in current table */ 1314 1315 1316 /* Generate counts for each bit length */ 1317 el = n > 256 ? b[256] : BMAX; /* set length of EOB code, if any */ 1318 memzero((char *)c, sizeof(c)); 1319 p = (unsigned *)b; i = n; 1320 do { 1321 c[*p]++; p++; /* assume all entries <= BMAX */ 1322 } while (--i); 1323 if (c[0] == n) /* null input--all zero length codes */ 1324 { 1325 *t = (struct huft *)NULL; 1326 *m = 0; 1327 return 0; 1328 } 1329 1330 1331 /* Find minimum and maximum length, bound *m by those */ 1332 for (j = 1; j <= BMAX; j++) 1333 if (c[j]) 1334 break; 1335 k = j; /* minimum code length */ 1336 if ((unsigned)*m < j) 1337 *m = j; 1338 for (i = BMAX; i; i--) 1339 if (c[i]) 1340 break; 1341 g = i; /* maximum code length */ 1342 if ((unsigned)*m > i) 1343 *m = i; 1344 1345 1346 /* Adjust last length count to fill out codes, if needed */ 1347 for (y = 1 << j; j < i; j++, y <<= 1) 1348 if ((y -= c[j]) < 0) 1349 return 2; /* bad input: more codes than bits */ 1350 if ((y -= c[i]) < 0) 1351 return 2; 1352 c[i] += y; 1353 1354 1355 /* Generate starting offsets into the value table for each length */ 1356 x[1] = j = 0; 1357 p = c + 1; xp = x + 2; 1358 while (--i) { /* note that i == g from above */ 1359 *xp++ = (j += *p++); 1360 } 1361 1362 1363 /* Make a table of values in order of bit lengths */ 1364 memzero((char *)v, sizeof(v)); 1365 p = (unsigned *)b; i = 0; 1366 do { 1367 if ((j = *p++) != 0) 1368 v[x[j]++] = i; 1369 } while (++i < n); 1370 n = x[g]; /* set n to length of v */ 1371 1372 1373 /* Generate the Huffman codes and for each, make the table entries */ 1374 x[0] = i = 0; /* first Huffman code is zero */ 1375 p = v; /* grab values in bit order */ 1376 h = -1; /* no tables yet--level -1 */ 1377 w = l[-1] = 0; /* no bits decoded yet */ 1378 u[0] = (struct huft *)NULL; /* just to keep compilers happy */ 1379 q = (struct huft *)NULL; /* ditto */ 1380 z = 0; /* ditto */ 1381 1382 /* go through the bit lengths (k already is bits in shortest code) */ 1383 for (; k <= g; k++) 1384 { 1385 a = c[k]; 1386 while (a--) 1387 { 1388 /* here i is the Huffman code of length k bits for value *p */ 1389 /* make tables up to required level */ 1390 while (k > w + l[h]) 1391 { 1392 w += l[h++]; /* add bits already decoded */ 1393 1394 /* compute minimum size table less than or equal to *m bits */ 1395 z = (z = g - w) > (unsigned)*m ? *m : z; /* upper limit */ 1396 if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */ 1397 { /* too few codes for k-w bit table */ 1398 f -= a + 1; /* deduct codes from patterns left */ 1399 xp = c + k; 1400 while (++j < z) /* try smaller tables up to z bits */ 1401 { 1402 if ((f <<= 1) <= *++xp) 1403 break; /* enough codes to use up j bits */ 1404 f -= *xp; /* else deduct codes from patterns */ 1405 } 1406 } 1407 if ((unsigned)w + j > el && (unsigned)w < el) 1408 j = el - w; /* make EOB code end at table */ 1409 z = 1 << j; /* table entries for j-bit table */ 1410 l[h] = j; /* set table size in stack */ 1411 1412 /* allocate and link in new table */ 1413 if ((q = (struct huft *)malloc((z + 1)*sizeof(struct huft))) == 1414 (struct huft *)NULL) 1415 { 1416 if (h) 1417 huft_free(u[0]); 1418 return 3; /* not enough memory */ 1419 } 1420#ifdef DEBUG 1421 G.hufts += z + 1; /* track memory usage */ 1422#endif 1423 *t = q + 1; /* link to list for huft_free() */ 1424 *(t = &(q->v.t)) = (struct huft *)NULL; 1425 u[h] = ++q; /* table starts after link */ 1426 1427 /* connect to last table, if there is one */ 1428 if (h) 1429 { 1430 x[h] = i; /* save pattern for backing up */ 1431 r.b = (uch)l[h-1]; /* bits to dump before this table */ 1432 r.e = (uch)(32 + j); /* bits in this table */ 1433 r.v.t = q; /* pointer to this table */ 1434 j = (i & ((1 << w) - 1)) >> (w - l[h-1]); 1435 u[h-1][j] = r; /* connect to last table */ 1436 } 1437 } 1438 1439 /* set up table entry in r */ 1440 r.b = (uch)(k - w); 1441 if (p >= v + n) 1442 r.e = INVALID_CODE; /* out of values--invalid code */ 1443 else if (*p < s) 1444 { 1445 r.e = (uch)(*p < 256 ? 32 : 31); /* 256 is end-of-block code */ 1446 r.v.n = (ush)*p++; /* simple code is just the value */ 1447 } 1448 else 1449 { 1450 r.e = e[*p - s]; /* non-simple--look up in lists */ 1451 r.v.n = d[*p++ - s]; 1452 } 1453 1454 /* fill code-like entries with r */ 1455 f = 1 << (k - w); 1456 for (j = i >> w; j < z; j += f) 1457 q[j] = r; 1458 1459 /* backwards increment the k-bit code i */ 1460 for (j = 1 << (k - 1); i & j; j >>= 1) 1461 i ^= j; 1462 i ^= j; 1463 1464 /* backup over finished tables */ 1465 while ((i & ((1 << w) - 1)) != x[h]) 1466 w -= l[--h]; /* don't need to update q */ 1467 } 1468 } 1469 1470 1471 /* return actual size of base table */ 1472 *m = l[0]; 1473 1474 1475 /* Return true (1) if we were given an incomplete table */ 1476 return y != 0 && g != 1; 1477} 1478 1479 1480 1481int huft_free(t) 1482struct huft *t; /* table to free */ 1483/* Free the malloc'ed tables built by huft_build(), which makes a linked 1484 list of the tables it made, with the links in a dummy first entry of 1485 each table. */ 1486{ 1487 register struct huft *p, *q; 1488 1489 1490 /* Go through linked list, freeing from the malloced (t[-1]) address. */ 1491 p = t; 1492 while (p != (struct huft *)NULL) 1493 { 1494 q = (--p)->v.t; 1495 free((zvoid *)p); 1496 p = q; 1497 } 1498 return 0; 1499} 1500