1 /* $NetBSD: zlib.c,v 1.33 2009/03/18 10:22:42 cegger Exp $ */ 2 /* 3 * This file is derived from various .h and .c files from the zlib-1.0.4 4 * distribution by Jean-loup Gailly and Mark Adler, with some additions 5 * by Paul Mackerras to aid in implementing Deflate compression and 6 * decompression for PPP packets. See zlib.h for conditions of 7 * distribution and use. 8 * 9 * Changes that have been made include: 10 * - added Z_PACKET_FLUSH (see zlib.h for details) 11 * - added inflateIncomp and deflateOutputPending 12 * - allow strm->next_out to be NULL, meaning discard the output 13 * 14 * $Id: zlib.c,v 1.33 2009/03/18 10:22:42 cegger Exp $ 15 */ 16 17 /* 18 * ==FILEVERSION 020312== 19 * 20 * This marker is used by the Linux installation script to determine 21 * whether an up-to-date version of this file is already installed. 22 */ 23 24 #include <sys/cdefs.h> 25 __KERNEL_RCSID(0, "$NetBSD: zlib.c,v 1.33 2009/03/18 10:22:42 cegger Exp $"); 26 27 #define NO_DUMMY_DECL 28 #define NO_ZCFUNCS 29 #define MY_ZCALLOC 30 31 #if defined(__FreeBSD__) && (defined(KERNEL) || defined(_KERNEL)) 32 #define inflate inflate_ppp /* FreeBSD already has an inflate :-( */ 33 #endif 34 35 36 /* +++ zutil.h */ 37 38 /* zutil.h -- internal interface and configuration of the compression library 39 * Copyright (C) 1995-2002 Jean-loup Gailly. 40 * For conditions of distribution and use, see copyright notice in zlib.h 41 */ 42 43 /* WARNING: this file should *not* be used by applications. It is 44 part of the implementation of the compression library and is 45 subject to change. Applications should only use zlib.h. 46 */ 47 48 /* @(#) $Id: zlib.c,v 1.33 2009/03/18 10:22:42 cegger Exp $ */ 49 50 #ifndef _Z_UTIL_H 51 #define _Z_UTIL_H 52 53 #include "zlib.h" 54 55 #if defined(KERNEL) || defined(_KERNEL) 56 /* Assume this is a *BSD or SVR4 kernel */ 57 #include <sys/param.h> 58 #include <sys/time.h> 59 #include <sys/systm.h> 60 # define HAVE_MEMCPY 61 #else 62 #if defined(__KERNEL__) 63 /* Assume this is a Linux kernel */ 64 #include <linux/string.h> 65 #define HAVE_MEMCPY 66 67 #else /* not kernel */ 68 69 #if defined(__NetBSD__) && (defined(_KERNEL) || defined(_STANDALONE)) 70 71 /* XXX doesn't seem to need anything at all, but this is for consistency. */ 72 # include <lib/libkern/libkern.h> 73 74 #else 75 # include <sys/types.h> 76 # include <sys/param.h> 77 #ifdef STDC 78 # include <stddef.h> 79 # include <string.h> 80 # include <stdlib.h> 81 #endif 82 #ifdef NO_ERRNO_H 83 extern int errno; 84 #else 85 # include <errno.h> 86 #endif 87 #endif /* __NetBSD__ && _STANDALONE */ 88 #endif /* __KERNEL__ */ 89 #endif /* _KERNEL || KERNEL */ 90 91 #ifndef local 92 # define local static 93 #endif 94 /* compile with -Dlocal if your debugger can't find static symbols */ 95 96 typedef unsigned char uch; 97 typedef uch FAR uchf; 98 typedef unsigned short ush; 99 typedef ush FAR ushf; 100 typedef unsigned long ulg; 101 102 extern const char *z_errmsg[10]; /* indexed by 2-zlib_error */ 103 /* (size given to avoid silly warnings with Visual C++) */ 104 105 #define ERR_MSG(err) z_errmsg[Z_NEED_DICT-(err)] 106 107 #define ERR_RETURN(strm,err) \ 108 return (strm->msg = ERR_MSG(err), (err)) 109 /* To be used only when the state is known to be valid */ 110 111 /* common constants */ 112 113 #ifndef DEF_WBITS 114 # define DEF_WBITS MAX_WBITS 115 #endif 116 /* default windowBits for decompression. MAX_WBITS is for compression only */ 117 118 #if MAX_MEM_LEVEL >= 8 119 # define DEF_MEM_LEVEL 8 120 #else 121 # define DEF_MEM_LEVEL MAX_MEM_LEVEL 122 #endif 123 /* default memLevel */ 124 125 #define STORED_BLOCK 0 126 #define STATIC_TREES 1 127 #define DYN_TREES 2 128 /* The three kinds of block type */ 129 130 #define MIN_MATCH 3 131 #define MAX_MATCH 258 132 /* The minimum and maximum match lengths */ 133 134 #define PRESET_DICT 0x20 /* preset dictionary flag in zlib header */ 135 136 /* target dependencies */ 137 138 #ifdef MSDOS 139 # define OS_CODE 0x00 140 # if defined(__TURBOC__) || defined(__BORLANDC__) 141 # if(__STDC__ == 1) && (defined(__LARGE__) || defined(__COMPACT__)) 142 /* Allow compilation with ANSI keywords only enabled */ 143 void _Cdecl farfree( void *block ); 144 void *_Cdecl farmalloc( unsigned long nbytes ); 145 # else 146 # include <alloc.h> 147 # endif 148 # else /* MSC or DJGPP */ 149 # include <malloc.h> 150 # endif 151 #endif 152 153 #ifdef OS2 154 # define OS_CODE 0x06 155 #endif 156 157 #ifdef WIN32 /* Window 95 & Windows NT */ 158 # define OS_CODE 0x0b 159 #endif 160 161 #if defined(VAXC) || defined(VMS) 162 # define OS_CODE 0x02 163 # define F_OPEN(name, mode) \ 164 fopen((name), (mode), "mbc=60", "ctx=stm", "rfm=fix", "mrs=512") 165 #endif 166 167 #ifdef AMIGA 168 # define OS_CODE 0x01 169 #endif 170 171 #if defined(ATARI) || defined(atarist) 172 # define OS_CODE 0x05 173 #endif 174 175 #if defined(MACOS) || defined(TARGET_OS_MAC) 176 # define OS_CODE 0x07 177 # if defined(__MWERKS__) && __dest_os != __be_os && __dest_os != __win32_os 178 # include <unix.h> /* for fdopen */ 179 # else 180 # ifndef fdopen 181 # define fdopen(fd,mode) NULL /* No fdopen() */ 182 # endif 183 # endif 184 #endif 185 186 #ifdef __50SERIES /* Prime/PRIMOS */ 187 # define OS_CODE 0x0F 188 #endif 189 190 #ifdef TOPS20 191 # define OS_CODE 0x0a 192 #endif 193 194 #if defined(_BEOS_) || defined(RISCOS) 195 # define fdopen(fd,mode) NULL /* No fdopen() */ 196 #endif 197 198 #if (defined(_MSC_VER) && (_MSC_VER > 600)) 199 # define fdopen(fd,type) _fdopen(fd,type) 200 #endif 201 202 203 /* Common defaults */ 204 205 #ifndef OS_CODE 206 # define OS_CODE 0x03 /* assume Unix */ 207 #endif 208 209 #ifndef F_OPEN 210 # define F_OPEN(name, mode) fopen((name), (mode)) 211 #endif 212 213 /* functions */ 214 215 #ifdef HAVE_STRERROR 216 extern char *strerror(int); 217 # define zstrerror(errnum) strerror(errnum) 218 #else 219 # define zstrerror(errnum) "" 220 #endif 221 222 #if defined(pyr) 223 # define NO_MEMCPY 224 #endif 225 #if defined(SMALL_MEDIUM) && !defined(_MSC_VER) && !defined(__SC__) 226 /* Use our own functions for small and medium model with MSC <= 5.0. 227 * You may have to use the same strategy for Borland C (untested). 228 * The __SC__ check is for Symantec. 229 */ 230 # define NO_MEMCPY 231 #endif 232 #if defined(STDC) && !defined(HAVE_MEMCPY) && !defined(NO_MEMCPY) 233 # define HAVE_MEMCPY 234 #endif 235 #ifdef HAVE_MEMCPY 236 # ifdef SMALL_MEDIUM /* MSDOS small or medium model */ 237 # define zmemcpy _fmemcpy 238 # define zmemcmp _fmemcmp 239 # define zmemzero(dest, len) _fmemset(dest, 0, len) 240 # else 241 # define zmemcpy memcpy 242 # define zmemcmp memcmp 243 # define zmemzero(dest, len) memset(dest, 0, len) 244 # endif 245 #else 246 extern void zmemcpy(Bytef* dest, const Bytef* source, uInt len); 247 extern int zmemcmp(const Bytef* s1, const Bytef* s2, uInt len); 248 extern void zmemzero(Bytef* dest, uInt len); 249 #endif 250 251 /* Diagnostic functions */ 252 #if defined(DEBUG_ZLIB) && !defined(_KERNEL) && !defined(_STANDALONE) 253 # include <stdio.h> 254 extern int z_verbose; 255 extern void z_error(char *m); 256 # define Assert(cond,msg) {if(!(cond)) z_error(msg);} 257 # define Trace(x) {if (z_verbose>=0) fprintf x ;} 258 # define Tracev(x) {if (z_verbose>0) fprintf x ;} 259 # define Tracevv(x) {if (z_verbose>1) fprintf x ;} 260 # define Tracec(c,x) {if (z_verbose>0 && (c)) fprintf x ;} 261 # define Tracecv(c,x) {if (z_verbose>1 && (c)) fprintf x ;} 262 #else 263 # define Assert(cond,msg) 264 # define Trace(x) 265 # define Tracev(x) 266 # define Tracevv(x) 267 # define Tracec(c,x) 268 # define Tracecv(c,x) 269 #endif 270 271 272 typedef uLong (ZEXPORT *check_func)(uLong check, const Bytef *buf, 273 uInt len); 274 voidpf zcalloc(voidpf opaque, unsigned items, unsigned size); 275 void zcfree(voidpf opaque, voidpf ptr); 276 277 #define ZALLOC(strm, items, size) \ 278 (*((strm)->zalloc))((strm)->opaque, (items), (size)) 279 #define ZFREE(strm, addr) (*((strm)->zfree))((strm)->opaque, (voidpf)(addr)) 280 #define TRY_FREE(s, p) {if (p) ZFREE(s, p);} 281 282 #endif /* _Z_UTIL_H */ 283 /* --- zutil.h */ 284 285 /* +++ deflate.h */ 286 287 /* deflate.h -- internal compression state 288 * Copyright (C) 1995-2002 Jean-loup Gailly 289 * For conditions of distribution and use, see copyright notice in zlib.h 290 */ 291 292 /* WARNING: this file should *not* be used by applications. It is 293 part of the implementation of the compression library and is 294 subject to change. Applications should only use zlib.h. 295 */ 296 297 /* @(#) $Id: zlib.c,v 1.33 2009/03/18 10:22:42 cegger Exp $ */ 298 299 #ifndef _DEFLATE_H 300 #define _DEFLATE_H 301 302 /* #include "zutil.h" */ 303 304 /* =========================================================================== 305 * Internal compression state. 306 */ 307 308 #define LENGTH_CODES 29 309 /* number of length codes, not counting the special END_BLOCK code */ 310 311 #define LITERALS 256 312 /* number of literal bytes 0..255 */ 313 314 #define L_CODES (LITERALS+1+LENGTH_CODES) 315 /* number of Literal or Length codes, including the END_BLOCK code */ 316 317 #define D_CODES 30 318 /* number of distance codes */ 319 320 #define BL_CODES 19 321 /* number of codes used to transfer the bit lengths */ 322 323 #define HEAP_SIZE (2*L_CODES+1) 324 /* maximum heap size */ 325 326 #define MAX_BITS 15 327 /* All codes must not exceed MAX_BITS bits */ 328 329 #define INIT_STATE 42 330 #define BUSY_STATE 113 331 #define FINISH_STATE 666 332 /* Stream status */ 333 334 335 /* Data structure describing a single value and its code string. */ 336 typedef struct ct_data_s { 337 union { 338 ush freq; /* frequency count */ 339 ush code; /* bit string */ 340 } fc; 341 union { 342 ush dad; /* father node in Huffman tree */ 343 ush len; /* length of bit string */ 344 } dl; 345 } FAR ct_data; 346 347 #define Freq fc.freq 348 #define Code fc.code 349 #define Dad dl.dad 350 #define Len dl.len 351 352 typedef struct static_tree_desc_s static_tree_desc; 353 354 typedef struct tree_desc_s { 355 ct_data *dyn_tree; /* the dynamic tree */ 356 int max_code; /* largest code with non zero frequency */ 357 static_tree_desc *stat_desc; /* the corresponding static tree */ 358 } FAR tree_desc; 359 360 typedef ush Pos; 361 typedef Pos FAR Posf; 362 typedef unsigned IPos; 363 364 /* A Pos is an index in the character window. We use short instead of int to 365 * save space in the various tables. IPos is used only for parameter passing. 366 */ 367 368 typedef struct deflate_state { 369 z_streamp strm; /* pointer back to this zlib stream */ 370 int status; /* as the name implies */ 371 Bytef *pending_buf; /* output still pending */ 372 ulg pending_buf_size; /* size of pending_buf */ 373 Bytef *pending_out; /* next pending byte to output to the stream */ 374 int pending; /* nb of bytes in the pending buffer */ 375 int noheader; /* suppress zlib header and adler32 */ 376 Byte data_type; /* UNKNOWN, BINARY or ASCII */ 377 Byte method; /* STORED (for zip only) or DEFLATED */ 378 int last_flush; /* value of flush param for previous deflate call */ 379 380 /* used by deflate.c: */ 381 382 uInt w_size; /* LZ77 window size (32K by default) */ 383 uInt w_bits; /* log2(w_size) (8..16) */ 384 uInt w_mask; /* w_size - 1 */ 385 386 Bytef *window; 387 /* Sliding window. Input bytes are read into the second half of the window, 388 * and move to the first half later to keep a dictionary of at least wSize 389 * bytes. With this organization, matches are limited to a distance of 390 * wSize-MAX_MATCH bytes, but this ensures that IO is always 391 * performed with a length multiple of the block size. Also, it limits 392 * the window size to 64K, which is quite useful on MSDOS. 393 * To do: use the user input buffer as sliding window. 394 */ 395 396 ulg window_size; 397 /* Actual size of window: 2*wSize, except when the user input buffer 398 * is directly used as sliding window. 399 */ 400 401 Posf *prev; 402 /* Link to older string with same hash index. To limit the size of this 403 * array to 64K, this link is maintained only for the last 32K strings. 404 * An index in this array is thus a window index modulo 32K. 405 */ 406 407 Posf *head; /* Heads of the hash chains or NIL. */ 408 409 uInt ins_h; /* hash index of string to be inserted */ 410 uInt hash_size; /* number of elements in hash table */ 411 uInt hash_bits; /* log2(hash_size) */ 412 uInt hash_mask; /* hash_size-1 */ 413 414 uInt hash_shift; 415 /* Number of bits by which ins_h must be shifted at each input 416 * step. It must be such that after MIN_MATCH steps, the oldest 417 * byte no longer takes part in the hash key, that is: 418 * hash_shift * MIN_MATCH >= hash_bits 419 */ 420 421 long block_start; 422 /* Window position at the beginning of the current output block. Gets 423 * negative when the window is moved backwards. 424 */ 425 426 uInt match_length; /* length of best match */ 427 IPos prev_match; /* previous match */ 428 int match_available; /* set if previous match exists */ 429 uInt strstart; /* start of string to insert */ 430 uInt match_start; /* start of matching string */ 431 uInt lookahead; /* number of valid bytes ahead in window */ 432 433 uInt prev_length; 434 /* Length of the best match at previous step. Matches not greater than this 435 * are discarded. This is used in the lazy match evaluation. 436 */ 437 438 uInt max_chain_length; 439 /* To speed up deflation, hash chains are never searched beyond this 440 * length. A higher limit improves compression ratio but degrades the 441 * speed. 442 */ 443 444 uInt max_lazy_match; 445 /* Attempt to find a better match only when the current match is strictly 446 * smaller than this value. This mechanism is used only for compression 447 * levels >= 4. 448 */ 449 # define max_insert_length max_lazy_match 450 /* Insert new strings in the hash table only if the match length is not 451 * greater than this length. This saves time but degrades compression. 452 * max_insert_length is used only for compression levels <= 3. 453 */ 454 455 int level; /* compression level (1..9) */ 456 int strategy; /* favor or force Huffman coding*/ 457 458 uInt good_match; 459 /* Use a faster search when the previous match is longer than this */ 460 461 int nice_match; /* Stop searching when current match exceeds this */ 462 463 /* used by trees.c: */ 464 /* Didn't use ct_data typedef below to supress compiler warning */ 465 struct ct_data_s dyn_ltree[HEAP_SIZE]; /* literal and length tree */ 466 struct ct_data_s dyn_dtree[2*D_CODES+1]; /* distance tree */ 467 struct ct_data_s bl_tree[2*BL_CODES+1]; /* Huffman tree for bit lengths */ 468 469 struct tree_desc_s l_desc; /* desc. for literal tree */ 470 struct tree_desc_s d_desc; /* desc. for distance tree */ 471 struct tree_desc_s bl_desc; /* desc. for bit length tree */ 472 473 ush bl_count[MAX_BITS+1]; 474 /* number of codes at each bit length for an optimal tree */ 475 476 int heap[2*L_CODES+1]; /* heap used to build the Huffman trees */ 477 int heap_len; /* number of elements in the heap */ 478 int heap_max; /* element of largest frequency */ 479 /* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used. 480 * The same heap array is used to build all trees. 481 */ 482 483 uch depth[2*L_CODES+1]; 484 /* Depth of each subtree used as tie breaker for trees of equal frequency 485 */ 486 487 uchf *l_buf; /* buffer for literals or lengths */ 488 489 uInt lit_bufsize; 490 /* Size of match buffer for literals/lengths. There are 4 reasons for 491 * limiting lit_bufsize to 64K: 492 * - frequencies can be kept in 16 bit counters 493 * - if compression is not successful for the first block, all input 494 * data is still in the window so we can still emit a stored block even 495 * when input comes from standard input. (This can also be done for 496 * all blocks if lit_bufsize is not greater than 32K.) 497 * - if compression is not successful for a file smaller than 64K, we can 498 * even emit a stored file instead of a stored block (saving 5 bytes). 499 * This is applicable only for zip (not gzip or zlib). 500 * - creating new Huffman trees less frequently may not provide fast 501 * adaptation to changes in the input data statistics. (Take for 502 * example a binary file with poorly compressible code followed by 503 * a highly compressible string table.) Smaller buffer sizes give 504 * fast adaptation but have of course the overhead of transmitting 505 * trees more frequently. 506 * - I can't count above 4 507 */ 508 509 uInt last_lit; /* running index in l_buf */ 510 511 ushf *d_buf; 512 /* Buffer for distances. To simplify the code, d_buf and l_buf have 513 * the same number of elements. To use different lengths, an extra flag 514 * array would be necessary. 515 */ 516 517 ulg opt_len; /* bit length of current block with optimal trees */ 518 ulg static_len; /* bit length of current block with static trees */ 519 uInt matches; /* number of string matches in current block */ 520 int last_eob_len; /* bit length of EOB code for last block */ 521 522 #ifdef DEBUG_ZLIB 523 ulg compressed_len; /* total bit length of compressed file mod 2^32 */ 524 ulg bits_sent; /* bit length of compressed data sent mod 2^32 */ 525 #endif 526 527 ush bi_buf; 528 /* Output buffer. bits are inserted starting at the bottom (least 529 * significant bits). 530 */ 531 int bi_valid; 532 /* Number of valid bits in bi_buf. All bits above the last valid bit 533 * are always zero. 534 */ 535 536 } FAR deflate_state; 537 538 /* Output a byte on the stream. 539 * IN assertion: there is enough room in pending_buf. 540 */ 541 #define put_byte(s, c) {s->pending_buf[s->pending++] = (c);} 542 543 544 #define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1) 545 /* Minimum amount of lookahead, except at the end of the input file. 546 * See deflate.c for comments about the MIN_MATCH+1. 547 */ 548 549 #define MAX_DIST(s) ((s)->w_size-MIN_LOOKAHEAD) 550 /* In order to simplify the code, particularly on 16 bit machines, match 551 * distances are limited to MAX_DIST instead of WSIZE. 552 */ 553 554 /* in trees.c */ 555 void _tr_init(deflate_state *s); 556 int _tr_tally(deflate_state *s, unsigned dist, unsigned lc); 557 void _tr_flush_block(deflate_state *s, charf *buf, ulg stored_len, 558 int eof); 559 void _tr_align(deflate_state *s); 560 void _tr_stored_block(deflate_state *s, charf *buf, ulg stored_len, 561 int eof); 562 void _tr_stored_type_only(deflate_state *); 563 564 #define d_code(dist) \ 565 ((dist) < 256 ? _dist_code[dist] : _dist_code[256+((dist)>>7)]) 566 /* Mapping from a distance to a distance code. dist is the distance - 1 and 567 * must not have side effects. _dist_code[256] and _dist_code[257] are never 568 * used. 569 */ 570 571 #ifndef DEBUG_ZLIB 572 /* Inline versions of _tr_tally for speed: */ 573 574 #if defined(GEN_TREES_H) || !defined(STDC) 575 extern uch _length_code[]; 576 extern uch _dist_code[]; 577 #else 578 extern const uch _length_code[]; 579 extern const uch _dist_code[]; 580 #endif 581 582 # define _tr_tally_lit(s, c, flush) \ 583 { uch cc = (c); \ 584 s->d_buf[s->last_lit] = 0; \ 585 s->l_buf[s->last_lit++] = cc; \ 586 s->dyn_ltree[cc].Freq++; \ 587 flush = (s->last_lit == s->lit_bufsize-1); \ 588 } 589 # define _tr_tally_dist(s, distance, length, flush) \ 590 { uch len = (length); \ 591 ush dist = (distance); \ 592 s->d_buf[s->last_lit] = dist; \ 593 s->l_buf[s->last_lit++] = len; \ 594 dist--; \ 595 s->dyn_ltree[_length_code[len]+LITERALS+1].Freq++; \ 596 s->dyn_dtree[d_code(dist)].Freq++; \ 597 flush = (s->last_lit == s->lit_bufsize-1); \ 598 } 599 #else 600 # define _tr_tally_lit(s, c, flush) flush = _tr_tally(s, 0, c) 601 # define _tr_tally_dist(s, distance, length, flush) \ 602 flush = _tr_tally(s, distance, length) 603 #endif 604 605 #endif 606 /* --- deflate.h */ 607 608 /* +++ deflate.c */ 609 610 /* deflate.c -- compress data using the deflation algorithm 611 * Copyright (C) 1995-2002 Jean-loup Gailly. 612 * For conditions of distribution and use, see copyright notice in zlib.h 613 */ 614 615 /* 616 * ALGORITHM 617 * 618 * The "deflation" process depends on being able to identify portions 619 * of the input text which are identical to earlier input (within a 620 * sliding window trailing behind the input currently being processed). 621 * 622 * The most straightforward technique turns out to be the fastest for 623 * most input files: try all possible matches and select the longest. 624 * The key feature of this algorithm is that insertions into the string 625 * dictionary are very simple and thus fast, and deletions are avoided 626 * completely. Insertions are performed at each input character, whereas 627 * string matches are performed only when the previous match ends. So it 628 * is preferable to spend more time in matches to allow very fast string 629 * insertions and avoid deletions. The matching algorithm for small 630 * strings is inspired from that of Rabin & Karp. A brute force approach 631 * is used to find longer strings when a small match has been found. 632 * A similar algorithm is used in comic (by Jan-Mark Wams) and freeze 633 * (by Leonid Broukhis). 634 * A previous version of this file used a more sophisticated algorithm 635 * (by Fiala and Greene) which is guaranteed to run in linear amortized 636 * time, but has a larger average cost, uses more memory and is patented. 637 * However the F&G algorithm may be faster for some highly redundant 638 * files if the parameter max_chain_length (described below) is too large. 639 * 640 * ACKNOWLEDGEMENTS 641 * 642 * The idea of lazy evaluation of matches is due to Jan-Mark Wams, and 643 * I found it in 'freeze' written by Leonid Broukhis. 644 * Thanks to many people for bug reports and testing. 645 * 646 * REFERENCES 647 * 648 * Deutsch, L.P.,"DEFLATE Compressed Data Format Specification". 649 * Available in ftp://ds.internic.net/rfc/rfc1951.txt 650 * 651 * A description of the Rabin and Karp algorithm is given in the book 652 * "Algorithms" by R. Sedgewick, Addison-Wesley, p252. 653 * 654 * Fiala,E.R., and Greene,D.H. 655 * Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595 656 * 657 */ 658 659 /* @(#) $Id: zlib.c,v 1.33 2009/03/18 10:22:42 cegger Exp $ */ 660 661 /* #include "deflate.h" */ 662 663 const char deflate_copyright[] = 664 " deflate 1.1.4 Copyright 1995-2002 Jean-loup Gailly "; 665 /* 666 If you use the zlib library in a product, an acknowledgment is welcome 667 in the documentation of your product. If for some reason you cannot 668 include such an acknowledgment, I would appreciate that you keep this 669 copyright string in the executable of your product. 670 */ 671 672 /* =========================================================================== 673 * Function prototypes. 674 */ 675 typedef enum { 676 need_more, /* block not completed, need more input or more output */ 677 block_done, /* block flush performed */ 678 finish_started, /* finish started, need only more output at next deflate */ 679 finish_done /* finish done, accept no more input or output */ 680 } block_state; 681 682 typedef block_state (*compress_func)(deflate_state *s, int flush); 683 /* Compression function. Returns the block state after the call. */ 684 685 local void fill_window(deflate_state *s); 686 local block_state deflate_stored(deflate_state *s, int flush); 687 local block_state deflate_fast(deflate_state *s, int flush); 688 local block_state deflate_slow(deflate_state *s, int flush); 689 local void lm_init(deflate_state *s); 690 local void putShortMSB(deflate_state *s, uInt b); 691 local void flush_pending(z_streamp strm); 692 local int read_buf(z_streamp strm, Bytef *buf, unsigned size); 693 #ifdef ASMV 694 void match_init(void); /* asm code initialization */ 695 uInt longest_match(deflate_state *s, IPos cur_match); 696 #else 697 local uInt longest_match(deflate_state *s, IPos cur_match); 698 #endif 699 700 #ifdef DEBUG_ZLIB 701 local void check_match(deflate_state *s, IPos start, IPos match, 702 int length); 703 #endif 704 705 /* =========================================================================== 706 * Local data 707 */ 708 709 #define NIL 0 710 /* Tail of hash chains */ 711 712 #ifndef TOO_FAR 713 # define TOO_FAR 4096 714 #endif 715 /* Matches of length 3 are discarded if their distance exceeds TOO_FAR */ 716 717 #define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1) 718 /* Minimum amount of lookahead, except at the end of the input file. 719 * See deflate.c for comments about the MIN_MATCH+1. 720 */ 721 722 /* Values for max_lazy_match, good_match and max_chain_length, depending on 723 * the desired pack level (0..9). The values given below have been tuned to 724 * exclude worst case performance for pathological files. Better values may be 725 * found for specific files. 726 */ 727 typedef struct config_s { 728 ush good_length; /* reduce lazy search above this match length */ 729 ush max_lazy; /* do not perform lazy search above this match length */ 730 ush nice_length; /* quit search above this match length */ 731 ush max_chain; 732 compress_func func; 733 } config; 734 735 local const config configuration_table[10] = { 736 /* good lazy nice chain */ 737 /* 0 */ {0, 0, 0, 0, deflate_stored}, /* store only */ 738 /* 1 */ {4, 4, 8, 4, deflate_fast}, /* maximum speed, no lazy matches */ 739 /* 2 */ {4, 5, 16, 8, deflate_fast}, 740 /* 3 */ {4, 6, 32, 32, deflate_fast}, 741 742 /* 4 */ {4, 4, 16, 16, deflate_slow}, /* lazy matches */ 743 /* 5 */ {8, 16, 32, 32, deflate_slow}, 744 /* 6 */ {8, 16, 128, 128, deflate_slow}, 745 /* 7 */ {8, 32, 128, 256, deflate_slow}, 746 /* 8 */ {32, 128, 258, 1024, deflate_slow}, 747 /* 9 */ {32, 258, 258, 4096, deflate_slow}}; /* maximum compression */ 748 749 /* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4 750 * For deflate_fast() (levels <= 3) good is ignored and lazy has a different 751 * meaning. 752 */ 753 754 #define EQUAL 0 755 /* result of memcmp for equal strings */ 756 757 #ifndef NO_DUMMY_DECL 758 struct static_tree_desc_s {int dummy;}; /* for buggy compilers */ 759 #endif 760 761 /* =========================================================================== 762 * Update a hash value with the given input byte 763 * IN assertion: all calls to to UPDATE_HASH are made with consecutive 764 * input characters, so that a running hash key can be computed from the 765 * previous key instead of complete recalculation each time. 766 */ 767 #define UPDATE_HASH(s,h,c) (h = (((h)<<s->hash_shift) ^ (c)) & s->hash_mask) 768 769 770 /* =========================================================================== 771 * Insert string str in the dictionary and set match_head to the previous head 772 * of the hash chain (the most recent string with same hash key). Return 773 * the previous length of the hash chain. 774 * If this file is compiled with -DFASTEST, the compression level is forced 775 * to 1, and no hash chains are maintained. 776 * IN assertion: all calls to to INSERT_STRING are made with consecutive 777 * input characters and the first MIN_MATCH bytes of str are valid 778 * (except for the last MIN_MATCH-1 bytes of the input file). 779 */ 780 #ifdef FASTEST 781 #define INSERT_STRING(s, str, match_head) \ 782 (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \ 783 match_head = s->head[s->ins_h], \ 784 s->head[s->ins_h] = (Pos)(str)) 785 #else 786 #define INSERT_STRING(s, str, match_head) \ 787 (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \ 788 s->prev[(str) & s->w_mask] = match_head = s->head[s->ins_h], \ 789 s->head[s->ins_h] = (Pos)(str)) 790 #endif 791 792 /* =========================================================================== 793 * Initialize the hash table (avoiding 64K overflow for 16 bit systems). 794 * prev[] will be initialized on the fly. 795 */ 796 #define CLEAR_HASH(s) \ 797 s->head[s->hash_size-1] = NIL; \ 798 zmemzero((Bytef *)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head)); 799 800 /* ========================================================================= */ 801 #if 0 802 int ZEXPORT deflateInit_(z_streamp strm, 803 int level, const char *version, int stream_size) 804 { 805 return deflateInit2_(strm, level, Z_DEFLATED, MAX_WBITS, DEF_MEM_LEVEL, 806 Z_DEFAULT_STRATEGY, version, stream_size); 807 /* To do: ignore strm->next_in if we use it as window */ 808 } 809 #endif 810 811 /* ========================================================================= */ 812 int ZEXPORT deflateInit2_(z_streamp strm, 813 int level, int method, int windowBits, int memLevel, int strategy, 814 const char *vers, int stream_size) 815 { 816 deflate_state *s; 817 int noheader = 0; 818 static const char* my_version = ZLIB_VERSION; 819 820 ushf *overlay; 821 /* We overlay pending_buf and d_buf+l_buf. This works since the average 822 * output size for (length,distance) codes is <= 24 bits. 823 */ 824 825 if (vers == Z_NULL || vers[0] != my_version[0] || 826 stream_size != sizeof(z_stream)) { 827 return Z_VERSION_ERROR; 828 } 829 if (strm == Z_NULL) return Z_STREAM_ERROR; 830 831 strm->msg = Z_NULL; 832 #ifndef NO_ZCFUNCS 833 if (strm->zalloc == Z_NULL) { 834 strm->zalloc = zcalloc; 835 strm->opaque = (voidpf)0; 836 } 837 if (strm->zfree == Z_NULL) strm->zfree = zcfree; 838 #endif 839 840 if (level == Z_DEFAULT_COMPRESSION) level = 6; 841 #ifdef FASTEST 842 level = 1; 843 #endif 844 845 if (windowBits < 0) { /* undocumented feature: suppress zlib header */ 846 noheader = 1; 847 windowBits = -windowBits; 848 } 849 if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED || 850 windowBits < 9 || windowBits > 15 || level < 0 || level > 9 || 851 strategy < 0 || strategy > Z_HUFFMAN_ONLY) { 852 return Z_STREAM_ERROR; 853 } 854 s = (deflate_state *) ZALLOC(strm, 1, sizeof(deflate_state)); 855 if (s == Z_NULL) return Z_MEM_ERROR; 856 strm->state = (struct internal_state FAR *)s; 857 s->strm = strm; 858 859 s->noheader = noheader; 860 s->w_bits = windowBits; 861 s->w_size = 1 << s->w_bits; 862 s->w_mask = s->w_size - 1; 863 864 s->hash_bits = memLevel + 7; 865 s->hash_size = 1 << s->hash_bits; 866 s->hash_mask = s->hash_size - 1; 867 s->hash_shift = ((s->hash_bits+MIN_MATCH-1)/MIN_MATCH); 868 869 s->window = (Bytef *) ZALLOC(strm, s->w_size, 2*sizeof(Byte)); 870 s->prev = (Posf *) ZALLOC(strm, s->w_size, sizeof(Pos)); 871 s->head = (Posf *) ZALLOC(strm, s->hash_size, sizeof(Pos)); 872 873 s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */ 874 875 overlay = (ushf *) ZALLOC(strm, s->lit_bufsize, sizeof(ush)+2); 876 s->pending_buf = (uchf *) overlay; 877 s->pending_buf_size = (ulg)s->lit_bufsize * (sizeof(ush)+2L); 878 879 if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL || 880 s->pending_buf == Z_NULL) { 881 strm->msg = ERR_MSG(Z_MEM_ERROR); 882 s->status = INIT_STATE; 883 deflateEnd (strm); 884 return Z_MEM_ERROR; 885 } 886 s->d_buf = overlay + s->lit_bufsize/sizeof(ush); 887 s->l_buf = s->pending_buf + (1+sizeof(ush))*s->lit_bufsize; 888 889 s->level = level; 890 s->strategy = strategy; 891 s->method = (Byte)method; 892 893 return deflateReset(strm); 894 } 895 896 /* ========================================================================= */ 897 #if 0 898 int ZEXPORT deflateSetDictionary (z_streamp strm, 899 const Bytef *dictionary, 900 uInt dictLength) 901 { 902 deflate_state *s; 903 uInt length = dictLength; 904 uInt n; 905 IPos hash_head = 0; 906 907 if (strm == Z_NULL || strm->state == Z_NULL || dictionary == Z_NULL) 908 return Z_STREAM_ERROR; 909 910 s = (deflate_state *)strm->state; 911 if (s->status != INIT_STATE) return Z_STREAM_ERROR; 912 913 strm->adler = adler32(strm->adler, dictionary, dictLength); 914 915 if (length < MIN_MATCH) return Z_OK; 916 if (length > MAX_DIST(s)) { 917 length = MAX_DIST(s); 918 #ifndef USE_DICT_HEAD 919 dictionary += dictLength - length; /* use the tail of the dictionary */ 920 #endif 921 } 922 zmemcpy(s->window, dictionary, length); 923 s->strstart = length; 924 s->block_start = (long)length; 925 926 /* Insert all strings in the hash table (except for the last two bytes). 927 * s->lookahead stays null, so s->ins_h will be recomputed at the next 928 * call of fill_window. 929 */ 930 s->ins_h = s->window[0]; 931 UPDATE_HASH(s, s->ins_h, s->window[1]); 932 for (n = 0; n <= length - MIN_MATCH; n++) { 933 INSERT_STRING(s, n, hash_head); 934 } 935 if (hash_head) hash_head = 0; /* to make compiler happy */ 936 return Z_OK; 937 } 938 #endif 939 940 /* ========================================================================= */ 941 int ZEXPORT deflateReset (z_streamp strm) 942 { 943 deflate_state *s; 944 945 if (strm == Z_NULL || strm->state == Z_NULL || 946 strm->zalloc == Z_NULL || strm->zfree == Z_NULL) return Z_STREAM_ERROR; 947 948 strm->total_in = strm->total_out = 0; 949 strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */ 950 strm->data_type = Z_UNKNOWN; 951 952 s = (deflate_state *)strm->state; 953 s->pending = 0; 954 s->pending_out = s->pending_buf; 955 956 if (s->noheader < 0) { 957 s->noheader = 0; /* was set to -1 by deflate(..., Z_FINISH); */ 958 } 959 s->status = s->noheader ? BUSY_STATE : INIT_STATE; 960 strm->adler = 1; 961 s->last_flush = Z_NO_FLUSH; 962 963 _tr_init(s); 964 lm_init(s); 965 966 return Z_OK; 967 } 968 969 /* ========================================================================= */ 970 #if 0 971 int ZEXPORT deflateParams(strm, level, strategy) 972 z_streamp strm; 973 int level; 974 int strategy; 975 { 976 deflate_state *s; 977 compress_func func; 978 int err = Z_OK; 979 980 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; 981 s = (deflate_state *)strm->state; 982 983 if (level == Z_DEFAULT_COMPRESSION) { 984 level = 6; 985 } 986 if (level < 0 || level > 9 || strategy < 0 || strategy > Z_HUFFMAN_ONLY) { 987 return Z_STREAM_ERROR; 988 } 989 func = configuration_table[s->level].func; 990 991 if (func != configuration_table[level].func && strm->total_in != 0) { 992 /* Flush the last buffer: */ 993 err = deflate(strm, Z_PARTIAL_FLUSH); 994 } 995 if (s->level != level) { 996 s->level = level; 997 s->max_lazy_match = configuration_table[level].max_lazy; 998 s->good_match = configuration_table[level].good_length; 999 s->nice_match = configuration_table[level].nice_length; 1000 s->max_chain_length = configuration_table[level].max_chain; 1001 } 1002 s->strategy = strategy; 1003 return err; 1004 } 1005 #endif 1006 1007 /* ========================================================================= 1008 * Put a short in the pending buffer. The 16-bit value is put in MSB order. 1009 * IN assertion: the stream state is correct and there is enough room in 1010 * pending_buf. 1011 */ 1012 local void putShortMSB (deflate_state *s, uInt b) 1013 { 1014 put_byte(s, (Byte)(b >> 8)); 1015 put_byte(s, (Byte)(b & 0xff)); 1016 } 1017 1018 /* ========================================================================= 1019 * Flush as much pending output as possible. All deflate() output goes 1020 * through this function so some applications may wish to modify it 1021 * to avoid allocating a large strm->next_out buffer and copying into it. 1022 * (See also read_buf()). 1023 */ 1024 local void flush_pending(z_streamp strm) 1025 { 1026 deflate_state *s = (deflate_state *) strm->state; 1027 unsigned len = s->pending; 1028 1029 if (len > strm->avail_out) len = strm->avail_out; 1030 if (len == 0) return; 1031 1032 if (strm->next_out != Z_NULL) { 1033 zmemcpy(strm->next_out, s->pending_out, len); 1034 strm->next_out += len; 1035 } 1036 s->pending_out += len; 1037 strm->total_out += len; 1038 strm->avail_out -= len; 1039 s->pending -= len; 1040 if (s->pending == 0) { 1041 s->pending_out = s->pending_buf; 1042 } 1043 } 1044 1045 /* ========================================================================= */ 1046 int ZEXPORT deflate (z_streamp strm, int flush) 1047 { 1048 int old_flush; /* value of flush param for previous deflate call */ 1049 deflate_state *s; 1050 1051 if (strm == Z_NULL || strm->state == Z_NULL || 1052 flush > Z_FINISH || flush < 0) { 1053 return Z_STREAM_ERROR; 1054 } 1055 s = (deflate_state *)strm->state; 1056 1057 if ((strm->next_in == Z_NULL && strm->avail_in != 0) || 1058 (s->status == FINISH_STATE && flush != Z_FINISH)) { 1059 ERR_RETURN(strm, Z_STREAM_ERROR); 1060 } 1061 if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR); 1062 1063 s->strm = strm; /* just in case */ 1064 old_flush = s->last_flush; 1065 s->last_flush = flush; 1066 1067 /* Write the zlib header */ 1068 if (s->status == INIT_STATE) { 1069 1070 uInt header = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8; 1071 uInt level_flags = (s->level-1) >> 1; 1072 1073 if (level_flags > 3) level_flags = 3; 1074 header |= (level_flags << 6); 1075 if (s->strstart != 0) header |= PRESET_DICT; 1076 header += 31 - (header % 31); 1077 1078 s->status = BUSY_STATE; 1079 putShortMSB(s, header); 1080 1081 /* Save the adler32 of the preset dictionary: */ 1082 if (s->strstart != 0) { 1083 putShortMSB(s, (uInt)(strm->adler >> 16)); 1084 putShortMSB(s, (uInt)(strm->adler & 0xffff)); 1085 } 1086 strm->adler = 1L; 1087 } 1088 1089 /* Flush as much pending output as possible */ 1090 if (s->pending != 0) { 1091 flush_pending(strm); 1092 if (strm->avail_out == 0) { 1093 /* Since avail_out is 0, deflate will be called again with 1094 * more output space, but possibly with both pending and 1095 * avail_in equal to zero. There won't be anything to do, 1096 * but this is not an error situation so make sure we 1097 * return OK instead of BUF_ERROR at next call of deflate: 1098 */ 1099 s->last_flush = -1; 1100 return Z_OK; 1101 } 1102 1103 /* Make sure there is something to do and avoid duplicate consecutive 1104 * flushes. For repeated and useless calls with Z_FINISH, we keep 1105 * returning Z_STREAM_END instead of Z_BUFF_ERROR. 1106 */ 1107 } else if (strm->avail_in == 0 && flush <= old_flush && 1108 flush != Z_FINISH) { 1109 ERR_RETURN(strm, Z_BUF_ERROR); 1110 } 1111 1112 /* User must not provide more input after the first FINISH: */ 1113 if (s->status == FINISH_STATE && strm->avail_in != 0) { 1114 ERR_RETURN(strm, Z_BUF_ERROR); 1115 } 1116 1117 /* Start a new block or continue the current one. 1118 */ 1119 if (strm->avail_in != 0 || s->lookahead != 0 || 1120 (flush != Z_NO_FLUSH && s->status != FINISH_STATE)) { 1121 block_state bstate; 1122 1123 bstate = (*(configuration_table[s->level].func))(s, flush); 1124 1125 if (bstate == finish_started || bstate == finish_done) { 1126 s->status = FINISH_STATE; 1127 } 1128 if (bstate == need_more || bstate == finish_started) { 1129 if (strm->avail_out == 0) { 1130 s->last_flush = -1; /* avoid BUF_ERROR next call, see above */ 1131 } 1132 return Z_OK; 1133 /* If flush != Z_NO_FLUSH && avail_out == 0, the next call 1134 * of deflate should use the same flush parameter to make sure 1135 * that the flush is complete. So we don't have to output an 1136 * empty block here, this will be done at next call. This also 1137 * ensures that for a very small output buffer, we emit at most 1138 * one empty block. 1139 */ 1140 } 1141 if (bstate == block_done) { 1142 if (flush == Z_PARTIAL_FLUSH) { 1143 _tr_align(s); 1144 } else if (flush == Z_PACKET_FLUSH) { 1145 /* Output just the 3-bit `stored' block type value, 1146 but not a zero length. */ 1147 _tr_stored_type_only(s); 1148 } else { /* FULL_FLUSH or SYNC_FLUSH */ 1149 _tr_stored_block(s, (char*)0, 0L, 0); 1150 /* For a full flush, this empty block will be recognized 1151 * as a special marker by inflate_sync(). 1152 */ 1153 if (flush == Z_FULL_FLUSH) { 1154 CLEAR_HASH(s); /* forget history */ 1155 } 1156 } 1157 flush_pending(strm); 1158 if (strm->avail_out == 0) { 1159 s->last_flush = -1; /* avoid BUF_ERROR at next call, see above */ 1160 return Z_OK; 1161 } 1162 } 1163 } 1164 Assert(strm->avail_out > 0, "bug2"); 1165 1166 if (flush != Z_FINISH) return Z_OK; 1167 if (s->noheader) return Z_STREAM_END; 1168 1169 /* Write the zlib trailer (adler32) */ 1170 putShortMSB(s, (uInt)(strm->adler >> 16)); 1171 putShortMSB(s, (uInt)(strm->adler & 0xffff)); 1172 flush_pending(strm); 1173 /* If avail_out is zero, the application will call deflate again 1174 * to flush the rest. 1175 */ 1176 s->noheader = -1; /* write the trailer only once! */ 1177 return s->pending != 0 ? Z_OK : Z_STREAM_END; 1178 } 1179 1180 /* ========================================================================= */ 1181 int ZEXPORT deflateEnd (z_streamp strm) 1182 { 1183 int status; 1184 deflate_state *s; 1185 1186 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; 1187 s = (deflate_state *) strm->state; 1188 1189 status = s->status; 1190 if (status != INIT_STATE && status != BUSY_STATE && 1191 status != FINISH_STATE) { 1192 return Z_STREAM_ERROR; 1193 } 1194 1195 /* Deallocate in reverse order of allocations: */ 1196 TRY_FREE(strm, s->pending_buf); 1197 TRY_FREE(strm, s->head); 1198 TRY_FREE(strm, s->prev); 1199 TRY_FREE(strm, s->window); 1200 1201 ZFREE(strm, s); 1202 strm->state = Z_NULL; 1203 1204 return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK; 1205 } 1206 1207 /* ========================================================================= 1208 * Copy the source state to the destination state. 1209 * To simplify the source, this is not supported for 16-bit MSDOS (which 1210 * doesn't have enough memory anyway to duplicate compression states). 1211 */ 1212 #if 0 1213 int ZEXPORT deflateCopy (z_streamp dest, z_streamp source) 1214 { 1215 #ifdef MAXSEG_64K 1216 return Z_STREAM_ERROR; 1217 #else 1218 deflate_state *ds; 1219 deflate_state *ss; 1220 ushf *overlay; 1221 1222 1223 if (source == Z_NULL || dest == Z_NULL || source->state == Z_NULL) { 1224 return Z_STREAM_ERROR; 1225 } 1226 1227 ss = (deflate_state *)source->state; 1228 1229 *dest = *source; 1230 1231 ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state)); 1232 if (ds == Z_NULL) return Z_MEM_ERROR; 1233 dest->state = (void *) ds; 1234 *ds = *ss; 1235 ds->strm = dest; 1236 1237 ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte)); 1238 ds->prev = (Posf *) ZALLOC(dest, ds->w_size, sizeof(Pos)); 1239 ds->head = (Posf *) ZALLOC(dest, ds->hash_size, sizeof(Pos)); 1240 overlay = (ushf *) ZALLOC(dest, ds->lit_bufsize, sizeof(ush)+2); 1241 ds->pending_buf = (uchf *) overlay; 1242 1243 if (ds->window == Z_NULL || ds->prev == Z_NULL || ds->head == Z_NULL || 1244 ds->pending_buf == Z_NULL) { 1245 ds->status = INIT_STATE; 1246 deflateEnd (dest); 1247 return Z_MEM_ERROR; 1248 } 1249 /* following zmemcpy do not work for 16-bit MSDOS */ 1250 zmemcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte)); 1251 zmemcpy(ds->prev, ss->prev, ds->w_size * sizeof(Pos)); 1252 zmemcpy(ds->head, ss->head, ds->hash_size * sizeof(Pos)); 1253 zmemcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size); 1254 1255 ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf); 1256 ds->d_buf = overlay + ds->lit_bufsize/sizeof(ush); 1257 ds->l_buf = ds->pending_buf + (1+sizeof(ush))*ds->lit_bufsize; 1258 1259 ds->l_desc.dyn_tree = ds->dyn_ltree; 1260 ds->d_desc.dyn_tree = ds->dyn_dtree; 1261 ds->bl_desc.dyn_tree = ds->bl_tree; 1262 1263 return Z_OK; 1264 #endif 1265 } 1266 #endif 1267 1268 /* =========================================================================== 1269 * Return the number of bytes of output which are immediately available 1270 * for output from the decompressor. 1271 */ 1272 #if 0 1273 int deflateOutputPending (z_streamp strm) 1274 { 1275 if (strm == Z_NULL || strm->state == Z_NULL) return 0; 1276 1277 return ((deflate_state *)(strm->state))->pending; 1278 } 1279 #endif 1280 1281 /* =========================================================================== 1282 * Read a new buffer from the current input stream, update the adler32 1283 * and total number of bytes read. All deflate() input goes through 1284 * this function so some applications may wish to modify it to avoid 1285 * allocating a large strm->next_in buffer and copying from it. 1286 * (See also flush_pending()). 1287 */ 1288 local int read_buf(z_streamp strm, 1289 Bytef *buf, 1290 unsigned size) 1291 { 1292 unsigned len = strm->avail_in; 1293 1294 if (len > size) len = size; 1295 if (len == 0) return 0; 1296 1297 strm->avail_in -= len; 1298 1299 if (!((deflate_state *)(strm->state))->noheader) { 1300 strm->adler = adler32(strm->adler, strm->next_in, len); 1301 } 1302 zmemcpy(buf, strm->next_in, len); 1303 strm->next_in += len; 1304 strm->total_in += len; 1305 1306 return (int)len; 1307 } 1308 1309 /* =========================================================================== 1310 * Initialize the "longest match" routines for a new zlib stream 1311 */ 1312 local void lm_init (deflate_state *s) 1313 { 1314 s->window_size = (ulg)2L*s->w_size; 1315 1316 CLEAR_HASH(s); 1317 1318 /* Set the default configuration parameters: 1319 */ 1320 s->max_lazy_match = configuration_table[s->level].max_lazy; 1321 s->good_match = configuration_table[s->level].good_length; 1322 s->nice_match = configuration_table[s->level].nice_length; 1323 s->max_chain_length = configuration_table[s->level].max_chain; 1324 1325 s->strstart = 0; 1326 s->block_start = 0L; 1327 s->lookahead = 0; 1328 s->match_length = s->prev_length = MIN_MATCH-1; 1329 s->match_available = 0; 1330 s->ins_h = 0; 1331 #ifdef ASMV 1332 match_init(); /* initialize the asm code */ 1333 #endif 1334 } 1335 1336 /* =========================================================================== 1337 * Set match_start to the longest match starting at the given string and 1338 * return its length. Matches shorter or equal to prev_length are discarded, 1339 * in which case the result is equal to prev_length and match_start is 1340 * garbage. 1341 * IN assertions: cur_match is the head of the hash chain for the current 1342 * string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1 1343 * OUT assertion: the match length is not greater than s->lookahead. 1344 */ 1345 #ifndef ASMV 1346 /* For 80x86 and 680x0, an optimized version will be provided in match.asm or 1347 * match.S. The code will be functionally equivalent. 1348 */ 1349 #ifndef FASTEST 1350 local uInt longest_match(deflate_state *s, 1351 IPos cur_match) /* current match */ 1352 { 1353 unsigned chain_length = s->max_chain_length;/* max hash chain length */ 1354 Bytef *scan = s->window + s->strstart; /* current string */ 1355 Bytef *match; /* matched string */ 1356 int len; /* length of current match */ 1357 int best_len = s->prev_length; /* best match length so far */ 1358 int nice_match = s->nice_match; /* stop if match long enough */ 1359 IPos limit = s->strstart > (IPos)MAX_DIST(s) ? 1360 s->strstart - (IPos)MAX_DIST(s) : NIL; 1361 /* Stop when cur_match becomes <= limit. To simplify the code, 1362 * we prevent matches with the string of window index 0. 1363 */ 1364 Posf *prev = s->prev; 1365 uInt wmask = s->w_mask; 1366 1367 #ifdef UNALIGNED_OK 1368 /* Compare two bytes at a time. Note: this is not always beneficial. 1369 * Try with and without -DUNALIGNED_OK to check. 1370 */ 1371 Bytef *strend = s->window + s->strstart + MAX_MATCH - 1; 1372 ush scan_start = *(ushf*)scan; 1373 ush scan_end = *(ushf*)(scan+best_len-1); 1374 #else 1375 Bytef *strend = s->window + s->strstart + MAX_MATCH; 1376 Byte scan_end1 = scan[best_len-1]; 1377 Byte scan_end = scan[best_len]; 1378 #endif 1379 1380 /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16. 1381 * It is easy to get rid of this optimization if necessary. 1382 */ 1383 Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever"); 1384 1385 /* Do not waste too much time if we already have a good match: */ 1386 if (s->prev_length >= s->good_match) { 1387 chain_length >>= 2; 1388 } 1389 /* Do not look for matches beyond the end of the input. This is necessary 1390 * to make deflate deterministic. 1391 */ 1392 if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead; 1393 1394 Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead"); 1395 1396 do { 1397 Assert(cur_match < s->strstart, "no future"); 1398 match = s->window + cur_match; 1399 1400 /* Skip to next match if the match length cannot increase 1401 * or if the match length is less than 2: 1402 */ 1403 #if (defined(UNALIGNED_OK) && MAX_MATCH == 258) 1404 /* This code assumes sizeof(unsigned short) == 2. Do not use 1405 * UNALIGNED_OK if your compiler uses a different size. 1406 */ 1407 if (*(ushf*)(match+best_len-1) != scan_end || 1408 *(ushf*)match != scan_start) continue; 1409 1410 /* It is not necessary to compare scan[2] and match[2] since they are 1411 * always equal when the other bytes match, given that the hash keys 1412 * are equal and that HASH_BITS >= 8. Compare 2 bytes at a time at 1413 * strstart+3, +5, ... up to strstart+257. We check for insufficient 1414 * lookahead only every 4th comparison; the 128th check will be made 1415 * at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is 1416 * necessary to put more guard bytes at the end of the window, or 1417 * to check more often for insufficient lookahead. 1418 */ 1419 Assert(scan[2] == match[2], "scan[2]?"); 1420 scan++, match++; 1421 do { 1422 } while (*(ushf*)(scan+=2) == *(ushf*)(match+=2) && 1423 *(ushf*)(scan+=2) == *(ushf*)(match+=2) && 1424 *(ushf*)(scan+=2) == *(ushf*)(match+=2) && 1425 *(ushf*)(scan+=2) == *(ushf*)(match+=2) && 1426 scan < strend); 1427 /* The funny "do {}" generates better code on most compilers */ 1428 1429 /* Here, scan <= window+strstart+257 */ 1430 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan"); 1431 if (*scan == *match) scan++; 1432 1433 len = (MAX_MATCH - 1) - (int)(strend-scan); 1434 scan = strend - (MAX_MATCH-1); 1435 1436 #else /* UNALIGNED_OK */ 1437 1438 if (match[best_len] != scan_end || 1439 match[best_len-1] != scan_end1 || 1440 *match != *scan || 1441 *++match != scan[1]) continue; 1442 1443 /* The check at best_len-1 can be removed because it will be made 1444 * again later. (This heuristic is not always a win.) 1445 * It is not necessary to compare scan[2] and match[2] since they 1446 * are always equal when the other bytes match, given that 1447 * the hash keys are equal and that HASH_BITS >= 8. 1448 */ 1449 scan += 2, match++; 1450 Assert(*scan == *match, "match[2]?"); 1451 1452 /* We check for insufficient lookahead only every 8th comparison; 1453 * the 256th check will be made at strstart+258. 1454 */ 1455 do { 1456 } while (*++scan == *++match && *++scan == *++match && 1457 *++scan == *++match && *++scan == *++match && 1458 *++scan == *++match && *++scan == *++match && 1459 *++scan == *++match && *++scan == *++match && 1460 scan < strend); 1461 1462 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan"); 1463 1464 len = MAX_MATCH - (int)(strend - scan); 1465 scan = strend - MAX_MATCH; 1466 1467 #endif /* UNALIGNED_OK */ 1468 1469 if (len > best_len) { 1470 s->match_start = cur_match; 1471 best_len = len; 1472 if (len >= nice_match) break; 1473 #ifdef UNALIGNED_OK 1474 scan_end = *(ushf*)(scan+best_len-1); 1475 #else 1476 scan_end1 = scan[best_len-1]; 1477 scan_end = scan[best_len]; 1478 #endif 1479 } 1480 } while ((cur_match = prev[cur_match & wmask]) > limit 1481 && --chain_length != 0); 1482 1483 if ((uInt)best_len <= s->lookahead) return (uInt)best_len; 1484 return s->lookahead; 1485 } 1486 1487 #else /* FASTEST */ 1488 /* --------------------------------------------------------------------------- 1489 * Optimized version for level == 1 only 1490 */ 1491 local uInt longest_match(s, cur_match) 1492 deflate_state *s; 1493 IPos cur_match; /* current match */ 1494 { 1495 register Bytef *scan = s->window + s->strstart; /* current string */ 1496 register Bytef *match; /* matched string */ 1497 register int len; /* length of current match */ 1498 register Bytef *strend = s->window + s->strstart + MAX_MATCH; 1499 1500 /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16. 1501 * It is easy to get rid of this optimization if necessary. 1502 */ 1503 Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever"); 1504 1505 Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead"); 1506 1507 Assert(cur_match < s->strstart, "no future"); 1508 1509 match = s->window + cur_match; 1510 1511 /* Return failure if the match length is less than 2: 1512 */ 1513 if (match[0] != scan[0] || match[1] != scan[1]) return MIN_MATCH-1; 1514 1515 /* The check at best_len-1 can be removed because it will be made 1516 * again later. (This heuristic is not always a win.) 1517 * It is not necessary to compare scan[2] and match[2] since they 1518 * are always equal when the other bytes match, given that 1519 * the hash keys are equal and that HASH_BITS >= 8. 1520 */ 1521 scan += 2, match += 2; 1522 Assert(*scan == *match, "match[2]?"); 1523 1524 /* We check for insufficient lookahead only every 8th comparison; 1525 * the 256th check will be made at strstart+258. 1526 */ 1527 do { 1528 } while (*++scan == *++match && *++scan == *++match && 1529 *++scan == *++match && *++scan == *++match && 1530 *++scan == *++match && *++scan == *++match && 1531 *++scan == *++match && *++scan == *++match && 1532 scan < strend); 1533 1534 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan"); 1535 1536 len = MAX_MATCH - (int)(strend - scan); 1537 1538 if (len < MIN_MATCH) return MIN_MATCH - 1; 1539 1540 s->match_start = cur_match; 1541 return len <= s->lookahead ? len : s->lookahead; 1542 } 1543 #endif /* FASTEST */ 1544 #endif /* ASMV */ 1545 1546 #ifdef DEBUG_ZLIB 1547 /* =========================================================================== 1548 * Check that the match at match_start is indeed a match. 1549 */ 1550 local void check_match(s, start, match, length) 1551 deflate_state *s; 1552 IPos start, match; 1553 int length; 1554 { 1555 /* check that the match is indeed a match */ 1556 if (zmemcmp(s->window + match, 1557 s->window + start, length) != EQUAL) { 1558 fprintf(stderr, " start %u, match %u, length %d\n", 1559 start, match, length); 1560 do { 1561 fprintf(stderr, "%c%c", s->window[match++], s->window[start++]); 1562 } while (--length != 0); 1563 z_error("invalid match"); 1564 } 1565 if (z_verbose > 1) { 1566 fprintf(stderr,"\\[%d,%d]", start-match, length); 1567 do { putc(s->window[start++], stderr); } while (--length != 0); 1568 } 1569 } 1570 #else 1571 # define check_match(s, start, match, length) 1572 #endif 1573 1574 /* =========================================================================== 1575 * Fill the window when the lookahead becomes insufficient. 1576 * Updates strstart and lookahead. 1577 * 1578 * IN assertion: lookahead < MIN_LOOKAHEAD 1579 * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD 1580 * At least one byte has been read, or avail_in == 0; reads are 1581 * performed for at least two bytes (required for the zip translate_eol 1582 * option -- not supported here). 1583 */ 1584 local void fill_window(deflate_state *s) 1585 { 1586 unsigned n, m; 1587 Posf *p; 1588 unsigned more; /* Amount of free space at the end of the window. */ 1589 uInt wsize = s->w_size; 1590 1591 do { 1592 more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart); 1593 1594 /* Deal with !@#$% 64K limit: */ 1595 if (more == 0 && s->strstart == 0 && s->lookahead == 0) { 1596 more = wsize; 1597 1598 } else if (more == (unsigned)(-1)) { 1599 /* Very unlikely, but possible on 16 bit machine if strstart == 0 1600 * and lookahead == 1 (input done one byte at time) 1601 */ 1602 more--; 1603 1604 /* If the window is almost full and there is insufficient lookahead, 1605 * move the upper half to the lower one to make room in the upper half. 1606 */ 1607 } else if (s->strstart >= wsize+MAX_DIST(s)) { 1608 1609 zmemcpy(s->window, s->window+wsize, (unsigned)wsize); 1610 s->match_start -= wsize; 1611 s->strstart -= wsize; /* we now have strstart >= MAX_DIST */ 1612 s->block_start -= (long) wsize; 1613 1614 /* Slide the hash table (could be avoided with 32 bit values 1615 at the expense of memory usage). We slide even when level == 0 1616 to keep the hash table consistent if we switch back to level > 0 1617 later. (Using level 0 permanently is not an optimal usage of 1618 zlib, so we don't care about this pathological case.) 1619 */ 1620 n = s->hash_size; 1621 p = &s->head[n]; 1622 do { 1623 m = *--p; 1624 *p = (Pos)(m >= wsize ? m-wsize : NIL); 1625 } while (--n); 1626 1627 n = wsize; 1628 #ifndef FASTEST 1629 p = &s->prev[n]; 1630 do { 1631 m = *--p; 1632 *p = (Pos)(m >= wsize ? m-wsize : NIL); 1633 /* If n is not on any hash chain, prev[n] is garbage but 1634 * its value will never be used. 1635 */ 1636 } while (--n); 1637 #endif 1638 more += wsize; 1639 } 1640 if (s->strm->avail_in == 0) return; 1641 1642 /* If there was no sliding: 1643 * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 && 1644 * more == window_size - lookahead - strstart 1645 * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1) 1646 * => more >= window_size - 2*WSIZE + 2 1647 * In the BIG_MEM or MMAP case (not yet supported), 1648 * window_size == input_size + MIN_LOOKAHEAD && 1649 * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD. 1650 * Otherwise, window_size == 2*WSIZE so more >= 2. 1651 * If there was sliding, more >= WSIZE. So in all cases, more >= 2. 1652 */ 1653 Assert(more >= 2, "more < 2"); 1654 1655 n = read_buf(s->strm, s->window + s->strstart + s->lookahead, more); 1656 s->lookahead += n; 1657 1658 /* Initialize the hash value now that we have some input: */ 1659 if (s->lookahead >= MIN_MATCH) { 1660 s->ins_h = s->window[s->strstart]; 1661 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]); 1662 #if MIN_MATCH != 3 1663 Call UPDATE_HASH() MIN_MATCH-3 more times 1664 #endif 1665 } 1666 /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage, 1667 * but this is not important since only literal bytes will be emitted. 1668 */ 1669 1670 } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0); 1671 } 1672 1673 /* =========================================================================== 1674 * Flush the current block, with given end-of-file flag. 1675 * IN assertion: strstart is set to the end of the current match. 1676 */ 1677 #define FLUSH_BLOCK_ONLY(s, eof) { \ 1678 _tr_flush_block(s, (s->block_start >= 0L ? \ 1679 (charf *)&s->window[(unsigned)s->block_start] : \ 1680 (charf *)Z_NULL), \ 1681 (ulg)((long)s->strstart - s->block_start), \ 1682 (eof)); \ 1683 s->block_start = s->strstart; \ 1684 flush_pending(s->strm); \ 1685 Tracev((stderr,"[FLUSH]")); \ 1686 } 1687 1688 /* Same but force premature exit if necessary. */ 1689 #define FLUSH_BLOCK(s, eof) { \ 1690 FLUSH_BLOCK_ONLY(s, eof); \ 1691 if (s->strm->avail_out == 0) return (eof) ? finish_started : need_more; \ 1692 } 1693 1694 /* =========================================================================== 1695 * Copy without compression as much as possible from the input stream, return 1696 * the current block state. 1697 * This function does not insert new strings in the dictionary since 1698 * uncompressible data is probably not useful. This function is used 1699 * only for the level=0 compression option. 1700 * NOTE: this function should be optimized to avoid extra copying from 1701 * window to pending_buf. 1702 */ 1703 local block_state deflate_stored(deflate_state *s, int flush) 1704 { 1705 /* Stored blocks are limited to 0xffff bytes, pending_buf is limited 1706 * to pending_buf_size, and each stored block has a 5 byte header: 1707 */ 1708 ulg max_block_size = 0xffff; 1709 ulg max_start; 1710 1711 if (max_block_size > s->pending_buf_size - 5) { 1712 max_block_size = s->pending_buf_size - 5; 1713 } 1714 1715 /* Copy as much as possible from input to output: */ 1716 for (;;) { 1717 /* Fill the window as much as possible: */ 1718 if (s->lookahead <= 1) { 1719 1720 Assert(s->strstart < s->w_size+MAX_DIST(s) || 1721 s->block_start >= (long)s->w_size, "slide too late"); 1722 1723 fill_window(s); 1724 if (s->lookahead == 0 && flush == Z_NO_FLUSH) return need_more; 1725 1726 if (s->lookahead == 0) break; /* flush the current block */ 1727 } 1728 Assert(s->block_start >= 0L, "block gone"); 1729 1730 s->strstart += s->lookahead; 1731 s->lookahead = 0; 1732 1733 /* Emit a stored block if pending_buf will be full: */ 1734 max_start = s->block_start + max_block_size; 1735 if (s->strstart == 0 || (ulg)s->strstart >= max_start) { 1736 /* strstart == 0 is possible when wraparound on 16-bit machine */ 1737 s->lookahead = (uInt)(s->strstart - max_start); 1738 s->strstart = (uInt)max_start; 1739 FLUSH_BLOCK(s, 0); 1740 } 1741 /* Flush if we may have to slide, otherwise block_start may become 1742 * negative and the data will be gone: 1743 */ 1744 if (s->strstart - (uInt)s->block_start >= MAX_DIST(s)) { 1745 FLUSH_BLOCK(s, 0); 1746 } 1747 } 1748 FLUSH_BLOCK(s, flush == Z_FINISH); 1749 return flush == Z_FINISH ? finish_done : block_done; 1750 } 1751 1752 /* =========================================================================== 1753 * Compress as much as possible from the input stream, return the current 1754 * block state. 1755 * This function does not perform lazy evaluation of matches and inserts 1756 * new strings in the dictionary only for unmatched strings or for short 1757 * matches. It is used only for the fast compression options. 1758 */ 1759 local block_state deflate_fast(deflate_state *s, int flush) 1760 { 1761 IPos hash_head = NIL; /* head of the hash chain */ 1762 int bflush; /* set if current block must be flushed */ 1763 1764 for (;;) { 1765 /* Make sure that we always have enough lookahead, except 1766 * at the end of the input file. We need MAX_MATCH bytes 1767 * for the next match, plus MIN_MATCH bytes to insert the 1768 * string following the next match. 1769 */ 1770 if (s->lookahead < MIN_LOOKAHEAD) { 1771 fill_window(s); 1772 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) { 1773 return need_more; 1774 } 1775 if (s->lookahead == 0) break; /* flush the current block */ 1776 } 1777 1778 /* Insert the string window[strstart .. strstart+2] in the 1779 * dictionary, and set hash_head to the head of the hash chain: 1780 */ 1781 if (s->lookahead >= MIN_MATCH) { 1782 INSERT_STRING(s, s->strstart, hash_head); 1783 } 1784 1785 /* Find the longest match, discarding those <= prev_length. 1786 * At this point we have always match_length < MIN_MATCH 1787 */ 1788 if (hash_head != NIL && s->strstart - hash_head <= MAX_DIST(s)) { 1789 /* To simplify the code, we prevent matches with the string 1790 * of window index 0 (in particular we have to avoid a match 1791 * of the string with itself at the start of the input file). 1792 */ 1793 if (s->strategy != Z_HUFFMAN_ONLY) { 1794 s->match_length = longest_match (s, hash_head); 1795 } 1796 /* longest_match() sets match_start */ 1797 } 1798 if (s->match_length >= MIN_MATCH) { 1799 check_match(s, s->strstart, s->match_start, s->match_length); 1800 1801 _tr_tally_dist(s, s->strstart - s->match_start, 1802 s->match_length - MIN_MATCH, bflush); 1803 1804 s->lookahead -= s->match_length; 1805 1806 /* Insert new strings in the hash table only if the match length 1807 * is not too large. This saves time but degrades compression. 1808 */ 1809 #ifndef FASTEST 1810 if (s->match_length <= s->max_insert_length && 1811 s->lookahead >= MIN_MATCH) { 1812 s->match_length--; /* string at strstart already in hash table */ 1813 do { 1814 s->strstart++; 1815 INSERT_STRING(s, s->strstart, hash_head); 1816 /* strstart never exceeds WSIZE-MAX_MATCH, so there are 1817 * always MIN_MATCH bytes ahead. 1818 */ 1819 } while (--s->match_length != 0); 1820 s->strstart++; 1821 } else 1822 #endif 1823 { 1824 s->strstart += s->match_length; 1825 s->match_length = 0; 1826 s->ins_h = s->window[s->strstart]; 1827 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]); 1828 #if MIN_MATCH != 3 1829 Call UPDATE_HASH() MIN_MATCH-3 more times 1830 #endif 1831 /* If lookahead < MIN_MATCH, ins_h is garbage, but it does not 1832 * matter since it will be recomputed at next deflate call. 1833 */ 1834 } 1835 } else { 1836 /* No match, output a literal byte */ 1837 Tracevv((stderr,"%c", s->window[s->strstart])); 1838 _tr_tally_lit (s, s->window[s->strstart], bflush); 1839 s->lookahead--; 1840 s->strstart++; 1841 } 1842 if (bflush) FLUSH_BLOCK(s, 0); 1843 } 1844 FLUSH_BLOCK(s, flush == Z_FINISH); 1845 return flush == Z_FINISH ? finish_done : block_done; 1846 } 1847 1848 /* =========================================================================== 1849 * Same as above, but achieves better compression. We use a lazy 1850 * evaluation for matches: a match is finally adopted only if there is 1851 * no better match at the next window position. 1852 */ 1853 local block_state deflate_slow(deflate_state *s, int flush) 1854 { 1855 IPos hash_head = NIL; /* head of hash chain */ 1856 int bflush; /* set if current block must be flushed */ 1857 1858 /* Process the input block. */ 1859 for (;;) { 1860 /* Make sure that we always have enough lookahead, except 1861 * at the end of the input file. We need MAX_MATCH bytes 1862 * for the next match, plus MIN_MATCH bytes to insert the 1863 * string following the next match. 1864 */ 1865 if (s->lookahead < MIN_LOOKAHEAD) { 1866 fill_window(s); 1867 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) { 1868 return need_more; 1869 } 1870 if (s->lookahead == 0) break; /* flush the current block */ 1871 } 1872 1873 /* Insert the string window[strstart .. strstart+2] in the 1874 * dictionary, and set hash_head to the head of the hash chain: 1875 */ 1876 if (s->lookahead >= MIN_MATCH) { 1877 INSERT_STRING(s, s->strstart, hash_head); 1878 } 1879 1880 /* Find the longest match, discarding those <= prev_length. 1881 */ 1882 s->prev_length = s->match_length, s->prev_match = s->match_start; 1883 s->match_length = MIN_MATCH-1; 1884 1885 if (hash_head != NIL && s->prev_length < s->max_lazy_match && 1886 s->strstart - hash_head <= MAX_DIST(s)) { 1887 /* To simplify the code, we prevent matches with the string 1888 * of window index 0 (in particular we have to avoid a match 1889 * of the string with itself at the start of the input file). 1890 */ 1891 if (s->strategy != Z_HUFFMAN_ONLY) { 1892 s->match_length = longest_match (s, hash_head); 1893 } 1894 /* longest_match() sets match_start */ 1895 1896 if (s->match_length <= 5 && (s->strategy == Z_FILTERED || 1897 (s->match_length == MIN_MATCH && 1898 s->strstart - s->match_start > TOO_FAR))) { 1899 1900 /* If prev_match is also MIN_MATCH, match_start is garbage 1901 * but we will ignore the current match anyway. 1902 */ 1903 s->match_length = MIN_MATCH-1; 1904 } 1905 } 1906 /* If there was a match at the previous step and the current 1907 * match is not better, output the previous match: 1908 */ 1909 if (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) { 1910 uInt max_insert = s->strstart + s->lookahead - MIN_MATCH; 1911 /* Do not insert strings in hash table beyond this. */ 1912 1913 check_match(s, s->strstart-1, s->prev_match, s->prev_length); 1914 1915 _tr_tally_dist(s, s->strstart -1 - s->prev_match, 1916 s->prev_length - MIN_MATCH, bflush); 1917 1918 /* Insert in hash table all strings up to the end of the match. 1919 * strstart-1 and strstart are already inserted. If there is not 1920 * enough lookahead, the last two strings are not inserted in 1921 * the hash table. 1922 */ 1923 s->lookahead -= s->prev_length-1; 1924 s->prev_length -= 2; 1925 do { 1926 if (++s->strstart <= max_insert) { 1927 INSERT_STRING(s, s->strstart, hash_head); 1928 } 1929 } while (--s->prev_length != 0); 1930 s->match_available = 0; 1931 s->match_length = MIN_MATCH-1; 1932 s->strstart++; 1933 1934 if (bflush) FLUSH_BLOCK(s, 0); 1935 1936 } else if (s->match_available) { 1937 /* If there was no match at the previous position, output a 1938 * single literal. If there was a match but the current match 1939 * is longer, truncate the previous match to a single literal. 1940 */ 1941 Tracevv((stderr,"%c", s->window[s->strstart-1])); 1942 _tr_tally_lit(s, s->window[s->strstart-1], bflush); 1943 if (bflush) { 1944 FLUSH_BLOCK_ONLY(s, 0); 1945 } 1946 s->strstart++; 1947 s->lookahead--; 1948 if (s->strm->avail_out == 0) return need_more; 1949 } else { 1950 /* There is no previous match to compare with, wait for 1951 * the next step to decide. 1952 */ 1953 s->match_available = 1; 1954 s->strstart++; 1955 s->lookahead--; 1956 } 1957 } 1958 Assert (flush != Z_NO_FLUSH, "no flush?"); 1959 if (s->match_available) { 1960 Tracevv((stderr,"%c", s->window[s->strstart-1])); 1961 _tr_tally_lit(s, s->window[s->strstart-1], bflush); 1962 s->match_available = 0; 1963 } 1964 FLUSH_BLOCK(s, flush == Z_FINISH); 1965 return flush == Z_FINISH ? finish_done : block_done; 1966 } 1967 /* --- deflate.c */ 1968 1969 /* +++ trees.c */ 1970 1971 /* trees.c -- output deflated data using Huffman coding 1972 * Copyright (C) 1995-2002 Jean-loup Gailly 1973 * For conditions of distribution and use, see copyright notice in zlib.h 1974 */ 1975 1976 /* 1977 * ALGORITHM 1978 * 1979 * The "deflation" process uses several Huffman trees. The more 1980 * common source values are represented by shorter bit sequences. 1981 * 1982 * Each code tree is stored in a compressed form which is itself 1983 * a Huffman encoding of the lengths of all the code strings (in 1984 * ascending order by source values). The actual code strings are 1985 * reconstructed from the lengths in the inflate process, as described 1986 * in the deflate specification. 1987 * 1988 * REFERENCES 1989 * 1990 * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification". 1991 * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc 1992 * 1993 * Storer, James A. 1994 * Data Compression: Methods and Theory, pp. 49-50. 1995 * Computer Science Press, 1988. ISBN 0-7167-8156-5. 1996 * 1997 * Sedgewick, R. 1998 * Algorithms, p290. 1999 * Addison-Wesley, 1983. ISBN 0-201-06672-6. 2000 */ 2001 2002 /* @(#) $Id: zlib.c,v 1.33 2009/03/18 10:22:42 cegger Exp $ */ 2003 2004 /* #define GEN_TREES_H */ 2005 2006 /* #include "deflate.h" */ 2007 2008 #ifdef DEBUG_ZLIB 2009 # include <ctype.h> 2010 #endif 2011 2012 /* =========================================================================== 2013 * Constants 2014 */ 2015 2016 #define MAX_BL_BITS 7 2017 /* Bit length codes must not exceed MAX_BL_BITS bits */ 2018 2019 #define END_BLOCK 256 2020 /* end of block literal code */ 2021 2022 #define REP_3_6 16 2023 /* repeat previous bit length 3-6 times (2 bits of repeat count) */ 2024 2025 #define REPZ_3_10 17 2026 /* repeat a zero length 3-10 times (3 bits of repeat count) */ 2027 2028 #define REPZ_11_138 18 2029 /* repeat a zero length 11-138 times (7 bits of repeat count) */ 2030 2031 local const int extra_lbits[LENGTH_CODES] /* extra bits for each length code */ 2032 = {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}; 2033 2034 local const int extra_dbits[D_CODES] /* extra bits for each distance code */ 2035 = {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}; 2036 2037 local const int extra_blbits[BL_CODES]/* extra bits for each bit length code */ 2038 = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7}; 2039 2040 local const uch bl_order[BL_CODES] 2041 = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15}; 2042 /* The lengths of the bit length codes are sent in order of decreasing 2043 * probability, to avoid transmitting the lengths for unused bit length codes. 2044 */ 2045 2046 #define Buf_size (8 * 2*sizeof(char)) 2047 /* Number of bits used within bi_buf. (bi_buf might be implemented on 2048 * more than 16 bits on some systems.) 2049 */ 2050 2051 /* =========================================================================== 2052 * Local data. These are initialized only once. 2053 */ 2054 2055 #define DIST_CODE_LEN 512 /* see definition of array dist_code below */ 2056 2057 #if defined(GEN_TREES_H) || !defined(STDC) 2058 /* non ANSI compilers may not accept trees.h */ 2059 2060 local ct_data static_ltree[L_CODES+2]; 2061 /* The static literal tree. Since the bit lengths are imposed, there is no 2062 * need for the L_CODES extra codes used during heap construction. However 2063 * The codes 286 and 287 are needed to build a canonical tree (see _tr_init 2064 * below). 2065 */ 2066 2067 local ct_data static_dtree[D_CODES]; 2068 /* The static distance tree. (Actually a trivial tree since all codes use 2069 * 5 bits.) 2070 */ 2071 2072 uch _dist_code[DIST_CODE_LEN]; 2073 /* Distance codes. The first 256 values correspond to the distances 2074 * 3 .. 258, the last 256 values correspond to the top 8 bits of 2075 * the 15 bit distances. 2076 */ 2077 2078 uch _length_code[MAX_MATCH-MIN_MATCH+1]; 2079 /* length code for each normalized match length (0 == MIN_MATCH) */ 2080 2081 local int base_length[LENGTH_CODES]; 2082 /* First normalized length for each code (0 = MIN_MATCH) */ 2083 2084 local int base_dist[D_CODES]; 2085 /* First normalized distance for each code (0 = distance of 1) */ 2086 2087 #else 2088 /* +++ trees.h */ 2089 2090 /* header created automatically with -DGEN_TREES_H */ 2091 2092 local const ct_data static_ltree[L_CODES+2] = { 2093 {{ 12},{ 8}}, {{140},{ 8}}, {{ 76},{ 8}}, {{204},{ 8}}, {{ 44},{ 8}}, 2094 {{172},{ 8}}, {{108},{ 8}}, {{236},{ 8}}, {{ 28},{ 8}}, {{156},{ 8}}, 2095 {{ 92},{ 8}}, {{220},{ 8}}, {{ 60},{ 8}}, {{188},{ 8}}, {{124},{ 8}}, 2096 {{252},{ 8}}, {{ 2},{ 8}}, {{130},{ 8}}, {{ 66},{ 8}}, {{194},{ 8}}, 2097 {{ 34},{ 8}}, {{162},{ 8}}, {{ 98},{ 8}}, {{226},{ 8}}, {{ 18},{ 8}}, 2098 {{146},{ 8}}, {{ 82},{ 8}}, {{210},{ 8}}, {{ 50},{ 8}}, {{178},{ 8}}, 2099 {{114},{ 8}}, {{242},{ 8}}, {{ 10},{ 8}}, {{138},{ 8}}, {{ 74},{ 8}}, 2100 {{202},{ 8}}, {{ 42},{ 8}}, {{170},{ 8}}, {{106},{ 8}}, {{234},{ 8}}, 2101 {{ 26},{ 8}}, {{154},{ 8}}, {{ 90},{ 8}}, {{218},{ 8}}, {{ 58},{ 8}}, 2102 {{186},{ 8}}, {{122},{ 8}}, {{250},{ 8}}, {{ 6},{ 8}}, {{134},{ 8}}, 2103 {{ 70},{ 8}}, {{198},{ 8}}, {{ 38},{ 8}}, {{166},{ 8}}, {{102},{ 8}}, 2104 {{230},{ 8}}, {{ 22},{ 8}}, {{150},{ 8}}, {{ 86},{ 8}}, {{214},{ 8}}, 2105 {{ 54},{ 8}}, {{182},{ 8}}, {{118},{ 8}}, {{246},{ 8}}, {{ 14},{ 8}}, 2106 {{142},{ 8}}, {{ 78},{ 8}}, {{206},{ 8}}, {{ 46},{ 8}}, {{174},{ 8}}, 2107 {{110},{ 8}}, {{238},{ 8}}, {{ 30},{ 8}}, {{158},{ 8}}, {{ 94},{ 8}}, 2108 {{222},{ 8}}, {{ 62},{ 8}}, {{190},{ 8}}, {{126},{ 8}}, {{254},{ 8}}, 2109 {{ 1},{ 8}}, {{129},{ 8}}, {{ 65},{ 8}}, {{193},{ 8}}, {{ 33},{ 8}}, 2110 {{161},{ 8}}, {{ 97},{ 8}}, {{225},{ 8}}, {{ 17},{ 8}}, {{145},{ 8}}, 2111 {{ 81},{ 8}}, {{209},{ 8}}, {{ 49},{ 8}}, {{177},{ 8}}, {{113},{ 8}}, 2112 {{241},{ 8}}, {{ 9},{ 8}}, {{137},{ 8}}, {{ 73},{ 8}}, {{201},{ 8}}, 2113 {{ 41},{ 8}}, {{169},{ 8}}, {{105},{ 8}}, {{233},{ 8}}, {{ 25},{ 8}}, 2114 {{153},{ 8}}, {{ 89},{ 8}}, {{217},{ 8}}, {{ 57},{ 8}}, {{185},{ 8}}, 2115 {{121},{ 8}}, {{249},{ 8}}, {{ 5},{ 8}}, {{133},{ 8}}, {{ 69},{ 8}}, 2116 {{197},{ 8}}, {{ 37},{ 8}}, {{165},{ 8}}, {{101},{ 8}}, {{229},{ 8}}, 2117 {{ 21},{ 8}}, {{149},{ 8}}, {{ 85},{ 8}}, {{213},{ 8}}, {{ 53},{ 8}}, 2118 {{181},{ 8}}, {{117},{ 8}}, {{245},{ 8}}, {{ 13},{ 8}}, {{141},{ 8}}, 2119 {{ 77},{ 8}}, {{205},{ 8}}, {{ 45},{ 8}}, {{173},{ 8}}, {{109},{ 8}}, 2120 {{237},{ 8}}, {{ 29},{ 8}}, {{157},{ 8}}, {{ 93},{ 8}}, {{221},{ 8}}, 2121 {{ 61},{ 8}}, {{189},{ 8}}, {{125},{ 8}}, {{253},{ 8}}, {{ 19},{ 9}}, 2122 {{275},{ 9}}, {{147},{ 9}}, {{403},{ 9}}, {{ 83},{ 9}}, {{339},{ 9}}, 2123 {{211},{ 9}}, {{467},{ 9}}, {{ 51},{ 9}}, {{307},{ 9}}, {{179},{ 9}}, 2124 {{435},{ 9}}, {{115},{ 9}}, {{371},{ 9}}, {{243},{ 9}}, {{499},{ 9}}, 2125 {{ 11},{ 9}}, {{267},{ 9}}, {{139},{ 9}}, {{395},{ 9}}, {{ 75},{ 9}}, 2126 {{331},{ 9}}, {{203},{ 9}}, {{459},{ 9}}, {{ 43},{ 9}}, {{299},{ 9}}, 2127 {{171},{ 9}}, {{427},{ 9}}, {{107},{ 9}}, {{363},{ 9}}, {{235},{ 9}}, 2128 {{491},{ 9}}, {{ 27},{ 9}}, {{283},{ 9}}, {{155},{ 9}}, {{411},{ 9}}, 2129 {{ 91},{ 9}}, {{347},{ 9}}, {{219},{ 9}}, {{475},{ 9}}, {{ 59},{ 9}}, 2130 {{315},{ 9}}, {{187},{ 9}}, {{443},{ 9}}, {{123},{ 9}}, {{379},{ 9}}, 2131 {{251},{ 9}}, {{507},{ 9}}, {{ 7},{ 9}}, {{263},{ 9}}, {{135},{ 9}}, 2132 {{391},{ 9}}, {{ 71},{ 9}}, {{327},{ 9}}, {{199},{ 9}}, {{455},{ 9}}, 2133 {{ 39},{ 9}}, {{295},{ 9}}, {{167},{ 9}}, {{423},{ 9}}, {{103},{ 9}}, 2134 {{359},{ 9}}, {{231},{ 9}}, {{487},{ 9}}, {{ 23},{ 9}}, {{279},{ 9}}, 2135 {{151},{ 9}}, {{407},{ 9}}, {{ 87},{ 9}}, {{343},{ 9}}, {{215},{ 9}}, 2136 {{471},{ 9}}, {{ 55},{ 9}}, {{311},{ 9}}, {{183},{ 9}}, {{439},{ 9}}, 2137 {{119},{ 9}}, {{375},{ 9}}, {{247},{ 9}}, {{503},{ 9}}, {{ 15},{ 9}}, 2138 {{271},{ 9}}, {{143},{ 9}}, {{399},{ 9}}, {{ 79},{ 9}}, {{335},{ 9}}, 2139 {{207},{ 9}}, {{463},{ 9}}, {{ 47},{ 9}}, {{303},{ 9}}, {{175},{ 9}}, 2140 {{431},{ 9}}, {{111},{ 9}}, {{367},{ 9}}, {{239},{ 9}}, {{495},{ 9}}, 2141 {{ 31},{ 9}}, {{287},{ 9}}, {{159},{ 9}}, {{415},{ 9}}, {{ 95},{ 9}}, 2142 {{351},{ 9}}, {{223},{ 9}}, {{479},{ 9}}, {{ 63},{ 9}}, {{319},{ 9}}, 2143 {{191},{ 9}}, {{447},{ 9}}, {{127},{ 9}}, {{383},{ 9}}, {{255},{ 9}}, 2144 {{511},{ 9}}, {{ 0},{ 7}}, {{ 64},{ 7}}, {{ 32},{ 7}}, {{ 96},{ 7}}, 2145 {{ 16},{ 7}}, {{ 80},{ 7}}, {{ 48},{ 7}}, {{112},{ 7}}, {{ 8},{ 7}}, 2146 {{ 72},{ 7}}, {{ 40},{ 7}}, {{104},{ 7}}, {{ 24},{ 7}}, {{ 88},{ 7}}, 2147 {{ 56},{ 7}}, {{120},{ 7}}, {{ 4},{ 7}}, {{ 68},{ 7}}, {{ 36},{ 7}}, 2148 {{100},{ 7}}, {{ 20},{ 7}}, {{ 84},{ 7}}, {{ 52},{ 7}}, {{116},{ 7}}, 2149 {{ 3},{ 8}}, {{131},{ 8}}, {{ 67},{ 8}}, {{195},{ 8}}, {{ 35},{ 8}}, 2150 {{163},{ 8}}, {{ 99},{ 8}}, {{227},{ 8}} 2151 }; 2152 2153 local const ct_data static_dtree[D_CODES] = { 2154 {{ 0},{ 5}}, {{16},{ 5}}, {{ 8},{ 5}}, {{24},{ 5}}, {{ 4},{ 5}}, 2155 {{20},{ 5}}, {{12},{ 5}}, {{28},{ 5}}, {{ 2},{ 5}}, {{18},{ 5}}, 2156 {{10},{ 5}}, {{26},{ 5}}, {{ 6},{ 5}}, {{22},{ 5}}, {{14},{ 5}}, 2157 {{30},{ 5}}, {{ 1},{ 5}}, {{17},{ 5}}, {{ 9},{ 5}}, {{25},{ 5}}, 2158 {{ 5},{ 5}}, {{21},{ 5}}, {{13},{ 5}}, {{29},{ 5}}, {{ 3},{ 5}}, 2159 {{19},{ 5}}, {{11},{ 5}}, {{27},{ 5}}, {{ 7},{ 5}}, {{23},{ 5}} 2160 }; 2161 2162 const uch _dist_code[DIST_CODE_LEN] = { 2163 0, 1, 2, 3, 4, 4, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8, 8, 2164 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 10, 2165 10, 10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 2166 11, 11, 11, 11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 2167 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 13, 13, 13, 13, 2168 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 2169 13, 13, 13, 13, 13, 13, 13, 13, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 2170 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 2171 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 2172 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 15, 15, 15, 15, 15, 15, 15, 15, 2173 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 2174 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 2175 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 0, 0, 16, 17, 2176 18, 18, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 22, 22, 22, 22, 22, 22, 22, 22, 2177 23, 23, 23, 23, 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 2178 24, 24, 24, 24, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 2179 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 2180 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 27, 27, 27, 27, 27, 27, 27, 27, 2181 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 2182 27, 27, 27, 27, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 2183 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 2184 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 2185 28, 28, 28, 28, 28, 28, 28, 28, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 2186 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 2187 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 2188 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29 2189 }; 2190 2191 const uch _length_code[MAX_MATCH-MIN_MATCH+1]= { 2192 0, 1, 2, 3, 4, 5, 6, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 12, 12, 2193 13, 13, 13, 13, 14, 14, 14, 14, 15, 15, 15, 15, 16, 16, 16, 16, 16, 16, 16, 16, 2194 17, 17, 17, 17, 17, 17, 17, 17, 18, 18, 18, 18, 18, 18, 18, 18, 19, 19, 19, 19, 2195 19, 19, 19, 19, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 2196 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 22, 22, 22, 22, 2197 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 23, 23, 23, 23, 23, 23, 23, 23, 2198 23, 23, 23, 23, 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 2199 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 2200 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 2201 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 26, 26, 26, 26, 26, 26, 26, 26, 2202 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 2203 26, 26, 26, 26, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 2204 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 28 2205 }; 2206 2207 local const int base_length[LENGTH_CODES] = { 2208 0, 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, 16, 20, 24, 28, 32, 40, 48, 56, 2209 64, 80, 96, 112, 128, 160, 192, 224, 0 2210 }; 2211 2212 local const int base_dist[D_CODES] = { 2213 0, 1, 2, 3, 4, 6, 8, 12, 16, 24, 2214 32, 48, 64, 96, 128, 192, 256, 384, 512, 768, 2215 1024, 1536, 2048, 3072, 4096, 6144, 8192, 12288, 16384, 24576 2216 }; 2217 /* --- trees.h */ 2218 2219 #endif /* GEN_TREES_H */ 2220 2221 struct static_tree_desc_s { 2222 const ct_data *static_tree; /* static tree or NULL */ 2223 const intf *extra_bits; /* extra bits for each code or NULL */ 2224 int extra_base; /* base index for extra_bits */ 2225 int elems; /* max number of elements in the tree */ 2226 int max_length; /* max bit length for the codes */ 2227 }; 2228 2229 local static_tree_desc static_l_desc = 2230 {static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS}; 2231 2232 local static_tree_desc static_d_desc = 2233 {static_dtree, extra_dbits, 0, D_CODES, MAX_BITS}; 2234 2235 local static_tree_desc static_bl_desc = 2236 {(const ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS}; 2237 2238 /* =========================================================================== 2239 * Local (static) routines in this file. 2240 */ 2241 2242 local void tr_static_init(void); 2243 local void init_block(deflate_state *s); 2244 local void pqdownheap(deflate_state *s, ct_data *tree, int k); 2245 local void gen_bitlen(deflate_state *s, tree_desc *desc); 2246 local void gen_codes(ct_data *tree, int max_code, ushf *bl_count); 2247 local void build_tree(deflate_state *s, tree_desc *desc); 2248 local void scan_tree(deflate_state *s, ct_data *tree, int max_code); 2249 local void send_tree(deflate_state *s, ct_data *tree, int max_code); 2250 local int build_bl_tree(deflate_state *s); 2251 local void send_all_trees(deflate_state *s, int lcodes, int dcodes, 2252 int blcodes); 2253 local void compress_block(deflate_state *s, const ct_data *ltree, 2254 const ct_data *dtree); 2255 local void set_data_type(deflate_state *s); 2256 local unsigned bi_reverse(unsigned value, int length); 2257 local void bi_windup(deflate_state *s); 2258 local void bi_flush(deflate_state *s); 2259 local void copy_block(deflate_state *s, charf *buf, unsigned len, 2260 int header); 2261 2262 #ifdef GEN_TREES_H 2263 local void gen_trees_header(void); 2264 #endif 2265 2266 #ifndef DEBUG_ZLIB 2267 # define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len) 2268 /* Send a code of the given tree. c and tree must not have side effects */ 2269 2270 #else /* DEBUG_ZLIB */ 2271 # define send_code(s, c, tree) \ 2272 { if (z_verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \ 2273 send_bits(s, tree[c].Code, tree[c].Len); } 2274 #endif 2275 2276 /* =========================================================================== 2277 * Output a short LSB first on the stream. 2278 * IN assertion: there is enough room in pendingBuf. 2279 */ 2280 #define put_short(s, w) { \ 2281 put_byte(s, (uch)((w) & 0xff)); \ 2282 put_byte(s, (uch)((ush)(w) >> 8)); \ 2283 } 2284 2285 /* =========================================================================== 2286 * Send a value on a given number of bits. 2287 * IN assertion: length <= 16 and value fits in length bits. 2288 */ 2289 #ifdef DEBUG_ZLIB 2290 local void send_bits(deflate_state *s, int value, int length); 2291 2292 local void send_bits(s, value, length) 2293 deflate_state *s; 2294 int value; /* value to send */ 2295 int length; /* number of bits */ 2296 { 2297 Tracevv((stderr," l %2d v %4x ", length, value)); 2298 Assert(length > 0 && length <= 15, "invalid length"); 2299 s->bits_sent += (ulg)length; 2300 2301 /* If not enough room in bi_buf, use (valid) bits from bi_buf and 2302 * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid)) 2303 * unused bits in value. 2304 */ 2305 if (s->bi_valid > (int)Buf_size - length) { 2306 s->bi_buf |= (value << s->bi_valid); 2307 put_short(s, s->bi_buf); 2308 s->bi_buf = (ush)value >> (Buf_size - s->bi_valid); 2309 s->bi_valid += length - Buf_size; 2310 } else { 2311 s->bi_buf |= value << s->bi_valid; 2312 s->bi_valid += length; 2313 } 2314 } 2315 #else /* !DEBUG_ZLIB */ 2316 2317 #define send_bits(s, value, length) \ 2318 { int len = length;\ 2319 if (s->bi_valid > (int)Buf_size - len) {\ 2320 int val = value;\ 2321 s->bi_buf |= (val << s->bi_valid);\ 2322 put_short(s, s->bi_buf);\ 2323 s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\ 2324 s->bi_valid += len - Buf_size;\ 2325 } else {\ 2326 s->bi_buf |= (value) << s->bi_valid;\ 2327 s->bi_valid += len;\ 2328 }\ 2329 } 2330 #endif /* DEBUG_ZLIB */ 2331 2332 2333 /* =========================================================================== 2334 * Initialize the various 'constant' tables. 2335 */ 2336 local void tr_static_init(void) 2337 { 2338 #if defined(GEN_TREES_H) || !defined(STDC) 2339 static int static_init_done = 0; 2340 int n; /* iterates over tree elements */ 2341 int bits; /* bit counter */ 2342 int length; /* length value */ 2343 int code; /* code value */ 2344 int dist; /* distance index */ 2345 ush bl_count[MAX_BITS+1]; 2346 /* number of codes at each bit length for an optimal tree */ 2347 2348 if (static_init_done) return; 2349 2350 /* For some embedded targets, global variables are not initialized: */ 2351 static_l_desc.static_tree = static_ltree; 2352 static_l_desc.extra_bits = extra_lbits; 2353 static_d_desc.static_tree = static_dtree; 2354 static_d_desc.extra_bits = extra_dbits; 2355 static_bl_desc.extra_bits = extra_blbits; 2356 2357 /* Initialize the mapping length (0..255) -> length code (0..28) */ 2358 length = 0; 2359 for (code = 0; code < LENGTH_CODES-1; code++) { 2360 base_length[code] = length; 2361 for (n = 0; n < (1<<extra_lbits[code]); n++) { 2362 _length_code[length++] = (uch)code; 2363 } 2364 } 2365 Assert (length == 256, "tr_static_init: length != 256"); 2366 /* Note that the length 255 (match length 258) can be represented 2367 * in two different ways: code 284 + 5 bits or code 285, so we 2368 * overwrite length_code[255] to use the best encoding: 2369 */ 2370 _length_code[length-1] = (uch)code; 2371 2372 /* Initialize the mapping dist (0..32K) -> dist code (0..29) */ 2373 dist = 0; 2374 for (code = 0 ; code < 16; code++) { 2375 base_dist[code] = dist; 2376 for (n = 0; n < (1<<extra_dbits[code]); n++) { 2377 _dist_code[dist++] = (uch)code; 2378 } 2379 } 2380 Assert (dist == 256, "tr_static_init: dist != 256"); 2381 dist >>= 7; /* from now on, all distances are divided by 128 */ 2382 for ( ; code < D_CODES; code++) { 2383 base_dist[code] = dist << 7; 2384 for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) { 2385 _dist_code[256 + dist++] = (uch)code; 2386 } 2387 } 2388 Assert (dist == 256, "tr_static_init: 256+dist != 512"); 2389 2390 /* Construct the codes of the static literal tree */ 2391 for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0; 2392 n = 0; 2393 while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++; 2394 while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++; 2395 while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++; 2396 while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++; 2397 /* Codes 286 and 287 do not exist, but we must include them in the 2398 * tree construction to get a canonical Huffman tree (longest code 2399 * all ones) 2400 */ 2401 gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count); 2402 2403 /* The static distance tree is trivial: */ 2404 for (n = 0; n < D_CODES; n++) { 2405 static_dtree[n].Len = 5; 2406 static_dtree[n].Code = bi_reverse((unsigned)n, 5); 2407 } 2408 static_init_done = 1; 2409 2410 # ifdef GEN_TREES_H 2411 gen_trees_header(); 2412 # endif 2413 #endif /* defined(GEN_TREES_H) || !defined(STDC) */ 2414 } 2415 2416 /* =========================================================================== 2417 * Genererate the file trees.h describing the static trees. 2418 */ 2419 #ifdef GEN_TREES_H 2420 # ifndef DEBUG_ZLIB 2421 # include <stdio.h> 2422 # endif 2423 2424 # define SEPARATOR(i, last, width) \ 2425 ((i) == (last)? "\n};\n\n" : \ 2426 ((i) % (width) == (width)-1 ? ",\n" : ", ")) 2427 2428 void gen_trees_header(void) 2429 { 2430 FILE *header = fopen("trees.h", "w"); 2431 int i; 2432 2433 Assert (header != NULL, "Can't open trees.h"); 2434 fprintf(header, 2435 "/* header created automatically with -DGEN_TREES_H */\n\n"); 2436 2437 fprintf(header, "local const ct_data static_ltree[L_CODES+2] = {\n"); 2438 for (i = 0; i < L_CODES+2; i++) { 2439 fprintf(header, "{{%3u},{%3u}}%s", static_ltree[i].Code, 2440 static_ltree[i].Len, SEPARATOR(i, L_CODES+1, 5)); 2441 } 2442 2443 fprintf(header, "local const ct_data static_dtree[D_CODES] = {\n"); 2444 for (i = 0; i < D_CODES; i++) { 2445 fprintf(header, "{{%2u},{%2u}}%s", static_dtree[i].Code, 2446 static_dtree[i].Len, SEPARATOR(i, D_CODES-1, 5)); 2447 } 2448 2449 fprintf(header, "const uch _dist_code[DIST_CODE_LEN] = {\n"); 2450 for (i = 0; i < DIST_CODE_LEN; i++) { 2451 fprintf(header, "%2u%s", _dist_code[i], 2452 SEPARATOR(i, DIST_CODE_LEN-1, 20)); 2453 } 2454 2455 fprintf(header, "const uch _length_code[MAX_MATCH-MIN_MATCH+1]= {\n"); 2456 for (i = 0; i < MAX_MATCH-MIN_MATCH+1; i++) { 2457 fprintf(header, "%2u%s", _length_code[i], 2458 SEPARATOR(i, MAX_MATCH-MIN_MATCH, 20)); 2459 } 2460 2461 fprintf(header, "local const int base_length[LENGTH_CODES] = {\n"); 2462 for (i = 0; i < LENGTH_CODES; i++) { 2463 fprintf(header, "%1u%s", base_length[i], 2464 SEPARATOR(i, LENGTH_CODES-1, 20)); 2465 } 2466 2467 fprintf(header, "local const int base_dist[D_CODES] = {\n"); 2468 for (i = 0; i < D_CODES; i++) { 2469 fprintf(header, "%5u%s", base_dist[i], 2470 SEPARATOR(i, D_CODES-1, 10)); 2471 } 2472 2473 fclose(header); 2474 } 2475 #endif /* GEN_TREES_H */ 2476 2477 /* =========================================================================== 2478 * Initialize the tree data structures for a new zlib stream. 2479 */ 2480 void _tr_init(deflate_state *s) 2481 { 2482 tr_static_init(); 2483 2484 s->l_desc.dyn_tree = s->dyn_ltree; 2485 s->l_desc.stat_desc = &static_l_desc; 2486 2487 s->d_desc.dyn_tree = s->dyn_dtree; 2488 s->d_desc.stat_desc = &static_d_desc; 2489 2490 s->bl_desc.dyn_tree = s->bl_tree; 2491 s->bl_desc.stat_desc = &static_bl_desc; 2492 2493 s->bi_buf = 0; 2494 s->bi_valid = 0; 2495 s->last_eob_len = 8; /* enough lookahead for inflate */ 2496 #ifdef DEBUG_ZLIB 2497 s->compressed_len = 0L; 2498 s->bits_sent = 0L; 2499 #endif 2500 2501 /* Initialize the first block of the first file: */ 2502 init_block(s); 2503 } 2504 2505 /* =========================================================================== 2506 * Initialize a new block. 2507 */ 2508 local void init_block(deflate_state *s) 2509 { 2510 int n; /* iterates over tree elements */ 2511 2512 /* Initialize the trees. */ 2513 for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0; 2514 for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0; 2515 for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0; 2516 2517 s->dyn_ltree[END_BLOCK].Freq = 1; 2518 s->opt_len = s->static_len = 0L; 2519 s->last_lit = s->matches = 0; 2520 } 2521 2522 #define SMALLEST 1 2523 /* Index within the heap array of least frequent node in the Huffman tree */ 2524 2525 2526 /* =========================================================================== 2527 * Remove the smallest element from the heap and recreate the heap with 2528 * one less element. Updates heap and heap_len. 2529 */ 2530 #define pqremove(s, tree, top) \ 2531 {\ 2532 top = s->heap[SMALLEST]; \ 2533 s->heap[SMALLEST] = s->heap[s->heap_len--]; \ 2534 pqdownheap(s, tree, SMALLEST); \ 2535 } 2536 2537 /* =========================================================================== 2538 * Compares to subtrees, using the tree depth as tie breaker when 2539 * the subtrees have equal frequency. This minimizes the worst case length. 2540 */ 2541 #define smaller(tree, n, m, depth) \ 2542 (tree[n].Freq < tree[m].Freq || \ 2543 (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m])) 2544 2545 /* =========================================================================== 2546 * Restore the heap property by moving down the tree starting at node k, 2547 * exchanging a node with the smallest of its two sons if necessary, stopping 2548 * when the heap property is re-established (each father smaller than its 2549 * two sons). 2550 */ 2551 local void pqdownheap(deflate_state *s, 2552 ct_data *tree, /* the tree to restore */ 2553 int k) /* node to move down */ 2554 { 2555 int v = s->heap[k]; 2556 int j = k << 1; /* left son of k */ 2557 while (j <= s->heap_len) { 2558 /* Set j to the smallest of the two sons: */ 2559 if (j < s->heap_len && 2560 smaller(tree, s->heap[j+1], s->heap[j], s->depth)) { 2561 j++; 2562 } 2563 /* Exit if v is smaller than both sons */ 2564 if (smaller(tree, v, s->heap[j], s->depth)) break; 2565 2566 /* Exchange v with the smallest son */ 2567 s->heap[k] = s->heap[j]; k = j; 2568 2569 /* And continue down the tree, setting j to the left son of k */ 2570 j <<= 1; 2571 } 2572 s->heap[k] = v; 2573 } 2574 2575 /* =========================================================================== 2576 * Compute the optimal bit lengths for a tree and update the total bit length 2577 * for the current block. 2578 * IN assertion: the fields freq and dad are set, heap[heap_max] and 2579 * above are the tree nodes sorted by increasing frequency. 2580 * OUT assertions: the field len is set to the optimal bit length, the 2581 * array bl_count contains the frequencies for each bit length. 2582 * The length opt_len is updated; static_len is also updated if stree is 2583 * not null. 2584 */ 2585 local void gen_bitlen(deflate_state *s, 2586 tree_desc *desc) /* the tree descriptor */ 2587 { 2588 ct_data *tree = desc->dyn_tree; 2589 int max_code = desc->max_code; 2590 const ct_data *stree = desc->stat_desc->static_tree; 2591 const intf *extra = desc->stat_desc->extra_bits; 2592 int base = desc->stat_desc->extra_base; 2593 int max_length = desc->stat_desc->max_length; 2594 int h; /* heap index */ 2595 int n, m; /* iterate over the tree elements */ 2596 int bits; /* bit length */ 2597 int xbits; /* extra bits */ 2598 ush f; /* frequency */ 2599 int overflow = 0; /* number of elements with bit length too large */ 2600 2601 for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0; 2602 2603 /* In a first pass, compute the optimal bit lengths (which may 2604 * overflow in the case of the bit length tree). 2605 */ 2606 tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */ 2607 2608 for (h = s->heap_max+1; h < HEAP_SIZE; h++) { 2609 n = s->heap[h]; 2610 bits = tree[tree[n].Dad].Len + 1; 2611 if (bits > max_length) bits = max_length, overflow++; 2612 tree[n].Len = (ush)bits; 2613 /* We overwrite tree[n].Dad which is no longer needed */ 2614 2615 if (n > max_code) continue; /* not a leaf node */ 2616 2617 s->bl_count[bits]++; 2618 xbits = 0; 2619 if (n >= base) xbits = extra[n-base]; 2620 f = tree[n].Freq; 2621 s->opt_len += (ulg)f * (bits + xbits); 2622 if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits); 2623 } 2624 if (overflow == 0) return; 2625 2626 Trace((stderr,"\nbit length overflow\n")); 2627 /* This happens for example on obj2 and pic of the Calgary corpus */ 2628 2629 /* Find the first bit length which could increase: */ 2630 do { 2631 bits = max_length-1; 2632 while (s->bl_count[bits] == 0) bits--; 2633 s->bl_count[bits]--; /* move one leaf down the tree */ 2634 s->bl_count[bits+1] += 2; /* move one overflow item as its brother */ 2635 s->bl_count[max_length]--; 2636 /* The brother of the overflow item also moves one step up, 2637 * but this does not affect bl_count[max_length] 2638 */ 2639 overflow -= 2; 2640 } while (overflow > 0); 2641 2642 /* Now recompute all bit lengths, scanning in increasing frequency. 2643 * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all 2644 * lengths instead of fixing only the wrong ones. This idea is taken 2645 * from 'ar' written by Haruhiko Okumura.) 2646 */ 2647 for (bits = max_length; bits != 0; bits--) { 2648 n = s->bl_count[bits]; 2649 while (n != 0) { 2650 m = s->heap[--h]; 2651 if (m > max_code) continue; 2652 if (tree[m].Len != (unsigned) bits) { 2653 Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits)); 2654 s->opt_len += ((long)bits - (long)tree[m].Len) 2655 *(long)tree[m].Freq; 2656 tree[m].Len = (ush)bits; 2657 } 2658 n--; 2659 } 2660 } 2661 } 2662 2663 /* =========================================================================== 2664 * Generate the codes for a given tree and bit counts (which need not be 2665 * optimal). 2666 * IN assertion: the array bl_count contains the bit length statistics for 2667 * the given tree and the field len is set for all tree elements. 2668 * OUT assertion: the field code is set for all tree elements of non 2669 * zero code length. 2670 */ 2671 local void gen_codes (ct_data *tree, /* the tree to decorate */ 2672 int max_code, /* largest code with non zero frequency */ 2673 ushf *bl_count) /* number of codes at each bit length */ 2674 { 2675 ush next_code[MAX_BITS+1]; /* next code value for each bit length */ 2676 ush code = 0; /* running code value */ 2677 int bits; /* bit index */ 2678 int n; /* code index */ 2679 2680 /* The distribution counts are first used to generate the code values 2681 * without bit reversal. 2682 */ 2683 for (bits = 1; bits <= MAX_BITS; bits++) { 2684 next_code[bits] = code = (code + bl_count[bits-1]) << 1; 2685 } 2686 /* Check that the bit counts in bl_count are consistent. The last code 2687 * must be all ones. 2688 */ 2689 Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1, 2690 "inconsistent bit counts"); 2691 Tracev((stderr,"\ngen_codes: max_code %d ", max_code)); 2692 2693 for (n = 0; n <= max_code; n++) { 2694 int len = tree[n].Len; 2695 if (len == 0) continue; 2696 /* Now reverse the bits */ 2697 tree[n].Code = bi_reverse(next_code[len]++, len); 2698 2699 Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ", 2700 n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1)); 2701 } 2702 } 2703 2704 /* =========================================================================== 2705 * Construct one Huffman tree and assigns the code bit strings and lengths. 2706 * Update the total bit length for the current block. 2707 * IN assertion: the field freq is set for all tree elements. 2708 * OUT assertions: the fields len and code are set to the optimal bit length 2709 * and corresponding code. The length opt_len is updated; static_len is 2710 * also updated if stree is not null. The field max_code is set. 2711 */ 2712 local void build_tree(deflate_state *s, 2713 tree_desc *desc) /* the tree descriptor */ 2714 { 2715 ct_data *tree = desc->dyn_tree; 2716 const ct_data *stree = desc->stat_desc->static_tree; 2717 int elems = desc->stat_desc->elems; 2718 int n, m; /* iterate over heap elements */ 2719 int max_code = -1; /* largest code with non zero frequency */ 2720 int node; /* new node being created */ 2721 2722 /* Construct the initial heap, with least frequent element in 2723 * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1]. 2724 * heap[0] is not used. 2725 */ 2726 s->heap_len = 0, s->heap_max = HEAP_SIZE; 2727 2728 for (n = 0; n < elems; n++) { 2729 if (tree[n].Freq != 0) { 2730 s->heap[++(s->heap_len)] = max_code = n; 2731 s->depth[n] = 0; 2732 } else { 2733 tree[n].Len = 0; 2734 } 2735 } 2736 2737 /* The pkzip format requires that at least one distance code exists, 2738 * and that at least one bit should be sent even if there is only one 2739 * possible code. So to avoid special checks later on we force at least 2740 * two codes of non zero frequency. 2741 */ 2742 while (s->heap_len < 2) { 2743 node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0); 2744 tree[node].Freq = 1; 2745 s->depth[node] = 0; 2746 s->opt_len--; if (stree) s->static_len -= stree[node].Len; 2747 /* node is 0 or 1 so it does not have extra bits */ 2748 } 2749 desc->max_code = max_code; 2750 2751 /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree, 2752 * establish sub-heaps of increasing lengths: 2753 */ 2754 for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n); 2755 2756 /* Construct the Huffman tree by repeatedly combining the least two 2757 * frequent nodes. 2758 */ 2759 node = elems; /* next internal node of the tree */ 2760 do { 2761 pqremove(s, tree, n); /* n = node of least frequency */ 2762 m = s->heap[SMALLEST]; /* m = node of next least frequency */ 2763 2764 s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */ 2765 s->heap[--(s->heap_max)] = m; 2766 2767 /* Create a new node father of n and m */ 2768 tree[node].Freq = tree[n].Freq + tree[m].Freq; 2769 s->depth[node] = (uch) (MAX(s->depth[n], s->depth[m]) + 1); 2770 tree[n].Dad = tree[m].Dad = (ush)node; 2771 #ifdef DUMP_BL_TREE 2772 if (tree == s->bl_tree) { 2773 fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)", 2774 node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq); 2775 } 2776 #endif 2777 /* and insert the new node in the heap */ 2778 s->heap[SMALLEST] = node++; 2779 pqdownheap(s, tree, SMALLEST); 2780 2781 } while (s->heap_len >= 2); 2782 2783 s->heap[--(s->heap_max)] = s->heap[SMALLEST]; 2784 2785 /* At this point, the fields freq and dad are set. We can now 2786 * generate the bit lengths. 2787 */ 2788 gen_bitlen(s, (tree_desc *)desc); 2789 2790 /* The field len is now set, we can generate the bit codes */ 2791 gen_codes ((ct_data *)tree, max_code, s->bl_count); 2792 } 2793 2794 /* =========================================================================== 2795 * Scan a literal or distance tree to determine the frequencies of the codes 2796 * in the bit length tree. 2797 */ 2798 local void scan_tree (deflate_state *s, 2799 ct_data *tree, /* the tree to be scanned */ 2800 int max_code) /* and its largest code of non zero frequency */ 2801 { 2802 int n; /* iterates over all tree elements */ 2803 int prevlen = -1; /* last emitted length */ 2804 int curlen; /* length of current code */ 2805 int nextlen = tree[0].Len; /* length of next code */ 2806 int count = 0; /* repeat count of the current code */ 2807 int max_count = 7; /* max repeat count */ 2808 int min_count = 4; /* min repeat count */ 2809 2810 if (nextlen == 0) max_count = 138, min_count = 3; 2811 tree[max_code+1].Len = (ush)0xffff; /* guard */ 2812 2813 for (n = 0; n <= max_code; n++) { 2814 curlen = nextlen; nextlen = tree[n+1].Len; 2815 if (++count < max_count && curlen == nextlen) { 2816 continue; 2817 } else if (count < min_count) { 2818 s->bl_tree[curlen].Freq += count; 2819 } else if (curlen != 0) { 2820 if (curlen != prevlen) s->bl_tree[curlen].Freq++; 2821 s->bl_tree[REP_3_6].Freq++; 2822 } else if (count <= 10) { 2823 s->bl_tree[REPZ_3_10].Freq++; 2824 } else { 2825 s->bl_tree[REPZ_11_138].Freq++; 2826 } 2827 count = 0; prevlen = curlen; 2828 if (nextlen == 0) { 2829 max_count = 138, min_count = 3; 2830 } else if (curlen == nextlen) { 2831 max_count = 6, min_count = 3; 2832 } else { 2833 max_count = 7, min_count = 4; 2834 } 2835 } 2836 } 2837 2838 /* =========================================================================== 2839 * Send a literal or distance tree in compressed form, using the codes in 2840 * bl_tree. 2841 */ 2842 local void send_tree (deflate_state *s, 2843 ct_data *tree, /* the tree to be scanned */ 2844 int max_code) /* and its largest code of non zero frequency */ 2845 { 2846 int n; /* iterates over all tree elements */ 2847 int prevlen = -1; /* last emitted length */ 2848 int curlen; /* length of current code */ 2849 int nextlen = tree[0].Len; /* length of next code */ 2850 int count = 0; /* repeat count of the current code */ 2851 int max_count = 7; /* max repeat count */ 2852 int min_count = 4; /* min repeat count */ 2853 2854 /* tree[max_code+1].Len = -1; */ /* guard already set */ 2855 if (nextlen == 0) max_count = 138, min_count = 3; 2856 2857 for (n = 0; n <= max_code; n++) { 2858 curlen = nextlen; nextlen = tree[n+1].Len; 2859 if (++count < max_count && curlen == nextlen) { 2860 continue; 2861 } else if (count < min_count) { 2862 do { send_code(s, curlen, s->bl_tree); } while (--count != 0); 2863 2864 } else if (curlen != 0) { 2865 if (curlen != prevlen) { 2866 send_code(s, curlen, s->bl_tree); count--; 2867 } 2868 Assert(count >= 3 && count <= 6, " 3_6?"); 2869 send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2); 2870 2871 } else if (count <= 10) { 2872 send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3); 2873 2874 } else { 2875 send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7); 2876 } 2877 count = 0; prevlen = curlen; 2878 if (nextlen == 0) { 2879 max_count = 138, min_count = 3; 2880 } else if (curlen == nextlen) { 2881 max_count = 6, min_count = 3; 2882 } else { 2883 max_count = 7, min_count = 4; 2884 } 2885 } 2886 } 2887 2888 /* =========================================================================== 2889 * Construct the Huffman tree for the bit lengths and return the index in 2890 * bl_order of the last bit length code to send. 2891 */ 2892 local int build_bl_tree(deflate_state *s) 2893 { 2894 int max_blindex; /* index of last bit length code of non zero freq */ 2895 2896 /* Determine the bit length frequencies for literal and distance trees */ 2897 scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code); 2898 scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code); 2899 2900 /* Build the bit length tree: */ 2901 build_tree(s, (tree_desc *)(&(s->bl_desc))); 2902 /* opt_len now includes the length of the tree representations, except 2903 * the lengths of the bit lengths codes and the 5+5+4 bits for the counts. 2904 */ 2905 2906 /* Determine the number of bit length codes to send. The pkzip format 2907 * requires that at least 4 bit length codes be sent. (appnote.txt says 2908 * 3 but the actual value used is 4.) 2909 */ 2910 for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) { 2911 if (s->bl_tree[bl_order[max_blindex]].Len != 0) break; 2912 } 2913 /* Update opt_len to include the bit length tree and counts */ 2914 s->opt_len += 3*(max_blindex+1) + 5+5+4; 2915 Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld", 2916 s->opt_len, s->static_len)); 2917 2918 return max_blindex; 2919 } 2920 2921 /* =========================================================================== 2922 * Send the header for a block using dynamic Huffman trees: the counts, the 2923 * lengths of the bit length codes, the literal tree and the distance tree. 2924 * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4. 2925 */ 2926 local void send_all_trees(deflate_state *s, 2927 int lcodes, int dcodes, int blcodes) /* number of codes for each tree */ 2928 { 2929 int rank; /* index in bl_order */ 2930 2931 Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes"); 2932 Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES, 2933 "too many codes"); 2934 Tracev((stderr, "\nbl counts: ")); 2935 send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */ 2936 send_bits(s, dcodes-1, 5); 2937 send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */ 2938 for (rank = 0; rank < blcodes; rank++) { 2939 Tracev((stderr, "\nbl code %2d ", bl_order[rank])); 2940 send_bits(s, s->bl_tree[bl_order[rank]].Len, 3); 2941 } 2942 Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent)); 2943 2944 send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */ 2945 Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent)); 2946 2947 send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */ 2948 Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent)); 2949 } 2950 2951 /* =========================================================================== 2952 * Send a stored block 2953 */ 2954 void _tr_stored_block(deflate_state *s, 2955 charf *buf, /* input block */ 2956 ulg stored_len, /* length of input block */ 2957 int eof) /* true if this is the last block for a file */ 2958 { 2959 send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */ 2960 #ifdef DEBUG_ZLIB 2961 s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L; 2962 s->compressed_len += (stored_len + 4) << 3; 2963 #endif 2964 copy_block(s, buf, (unsigned)stored_len, 1); /* with header */ 2965 } 2966 2967 /* Send just the `stored block' type code without any length bytes or data. 2968 */ 2969 void _tr_stored_type_only(deflate_state *s) 2970 { 2971 send_bits(s, (STORED_BLOCK << 1), 3); 2972 bi_windup(s); 2973 #ifdef DEBUG_ZLIB 2974 s->compressed_len = (s->compressed_len + 3) & ~7L; 2975 #endif 2976 } 2977 2978 /* =========================================================================== 2979 * Send one empty static block to give enough lookahead for inflate. 2980 * This takes 10 bits, of which 7 may remain in the bit buffer. 2981 * The current inflate code requires 9 bits of lookahead. If the 2982 * last two codes for the previous block (real code plus EOB) were coded 2983 * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode 2984 * the last real code. In this case we send two empty static blocks instead 2985 * of one. (There are no problems if the previous block is stored or fixed.) 2986 * To simplify the code, we assume the worst case of last real code encoded 2987 * on one bit only. 2988 */ 2989 void _tr_align(deflate_state *s) 2990 { 2991 send_bits(s, STATIC_TREES<<1, 3); 2992 send_code(s, END_BLOCK, static_ltree); 2993 #ifdef DEBUG_ZLIB 2994 s->compressed_len += 10L; /* 3 for block type, 7 for EOB */ 2995 #endif 2996 bi_flush(s); 2997 /* Of the 10 bits for the empty block, we have already sent 2998 * (10 - bi_valid) bits. The lookahead for the last real code (before 2999 * the EOB of the previous block) was thus at least one plus the length 3000 * of the EOB plus what we have just sent of the empty static block. 3001 */ 3002 if (1 + s->last_eob_len + 10 - s->bi_valid < 9) { 3003 send_bits(s, STATIC_TREES<<1, 3); 3004 send_code(s, END_BLOCK, static_ltree); 3005 #ifdef DEBUG_ZLIB 3006 s->compressed_len += 10L; 3007 #endif 3008 bi_flush(s); 3009 } 3010 s->last_eob_len = 7; 3011 } 3012 3013 /* =========================================================================== 3014 * Determine the best encoding for the current block: dynamic trees, static 3015 * trees or store, and output the encoded block to the zip file. 3016 */ 3017 void _tr_flush_block(deflate_state *s, 3018 charf *buf, /* input block, or NULL if too old */ 3019 ulg stored_len, /* length of input block */ 3020 int eof) /* true if this is the last block for a file */ 3021 { 3022 ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */ 3023 int max_blindex = 0; /* index of last bit length code of non zero freq */ 3024 3025 /* Build the Huffman trees unless a stored block is forced */ 3026 if (s->level > 0) { 3027 3028 /* Check if the file is ascii or binary */ 3029 if (s->data_type == Z_UNKNOWN) set_data_type(s); 3030 3031 /* Construct the literal and distance trees */ 3032 build_tree(s, (tree_desc *)(&(s->l_desc))); 3033 Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len, 3034 s->static_len)); 3035 3036 build_tree(s, (tree_desc *)(&(s->d_desc))); 3037 Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len, 3038 s->static_len)); 3039 /* At this point, opt_len and static_len are the total bit lengths of 3040 * the compressed block data, excluding the tree representations. 3041 */ 3042 3043 /* Build the bit length tree for the above two trees, and get the index 3044 * in bl_order of the last bit length code to send. 3045 */ 3046 max_blindex = build_bl_tree(s); 3047 3048 /* Determine the best encoding. Compute first the block length in bytes*/ 3049 opt_lenb = (s->opt_len+3+7)>>3; 3050 static_lenb = (s->static_len+3+7)>>3; 3051 3052 Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ", 3053 opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len, 3054 s->last_lit)); 3055 3056 if (static_lenb <= opt_lenb) opt_lenb = static_lenb; 3057 3058 } else { 3059 Assert(buf != (char*)0, "lost buf"); 3060 opt_lenb = static_lenb = stored_len + 5; /* force a stored block */ 3061 } 3062 3063 #ifdef FORCE_STORED 3064 if (buf != (char*)0) { /* force stored block */ 3065 #else 3066 if (stored_len+4 <= opt_lenb && buf != (char*)0) { 3067 /* 4: two words for the lengths */ 3068 #endif 3069 /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE. 3070 * Otherwise we can't have processed more than WSIZE input bytes since 3071 * the last block flush, because compression would have been 3072 * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to 3073 * transform a block into a stored block. 3074 */ 3075 _tr_stored_block(s, buf, stored_len, eof); 3076 3077 #ifdef FORCE_STATIC 3078 } else if (static_lenb >= 0) { /* force static trees */ 3079 #else 3080 } else if (static_lenb == opt_lenb) { 3081 #endif 3082 send_bits(s, (STATIC_TREES<<1)+eof, 3); 3083 compress_block(s, (const ct_data *)static_ltree, (const ct_data *)static_dtree); 3084 #ifdef DEBUG_ZLIB 3085 s->compressed_len += 3 + s->static_len; 3086 #endif 3087 } else { 3088 send_bits(s, (DYN_TREES<<1)+eof, 3); 3089 send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1, 3090 max_blindex+1); 3091 compress_block(s, (const ct_data *)s->dyn_ltree, (const ct_data *)s->dyn_dtree); 3092 #ifdef DEBUG_ZLIB 3093 s->compressed_len += 3 + s->opt_len; 3094 #endif 3095 } 3096 Assert (s->compressed_len == s->bits_sent, "bad compressed size"); 3097 /* The above check is made mod 2^32, for files larger than 512 MB 3098 * and uLong implemented on 32 bits. 3099 */ 3100 init_block(s); 3101 3102 if (eof) { 3103 bi_windup(s); 3104 #ifdef DEBUG_ZLIB 3105 s->compressed_len += 7; /* align on byte boundary */ 3106 #endif 3107 } 3108 Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3, 3109 s->compressed_len-7*eof)); 3110 } 3111 3112 /* =========================================================================== 3113 * Save the match info and tally the frequency counts. Return true if 3114 * the current block must be flushed. 3115 */ 3116 #if 0 3117 int _tr_tally (deflate_state *s, 3118 unsigned dist, /* distance of matched string */ 3119 unsigned lc) /* match length-MIN_MATCH or unmatched char (if dist==0) */ 3120 { 3121 s->d_buf[s->last_lit] = (ush)dist; 3122 s->l_buf[s->last_lit++] = (uch)lc; 3123 if (dist == 0) { 3124 /* lc is the unmatched char */ 3125 s->dyn_ltree[lc].Freq++; 3126 } else { 3127 s->matches++; 3128 /* Here, lc is the match length - MIN_MATCH */ 3129 dist--; /* dist = match distance - 1 */ 3130 Assert((ush)dist < (ush)MAX_DIST(s) && 3131 (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) && 3132 (ush)d_code(dist) < (ush)D_CODES, "_tr_tally: bad match"); 3133 3134 s->dyn_ltree[_length_code[lc]+LITERALS+1].Freq++; 3135 s->dyn_dtree[d_code(dist)].Freq++; 3136 } 3137 3138 #ifdef TRUNCATE_BLOCK 3139 /* Try to guess if it is profitable to stop the current block here */ 3140 if ((s->last_lit & 0x1fff) == 0 && s->level > 2) { 3141 /* Compute an upper bound for the compressed length */ 3142 ulg out_length = (ulg)s->last_lit*8L; 3143 ulg in_length = (ulg)((long)s->strstart - s->block_start); 3144 int dcode; 3145 for (dcode = 0; dcode < D_CODES; dcode++) { 3146 out_length += (ulg)s->dyn_dtree[dcode].Freq * 3147 (5L+extra_dbits[dcode]); 3148 } 3149 out_length >>= 3; 3150 Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ", 3151 s->last_lit, in_length, out_length, 3152 100L - out_length*100L/in_length)); 3153 if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1; 3154 } 3155 #endif 3156 return (s->last_lit == s->lit_bufsize-1); 3157 /* We avoid equality with lit_bufsize because of wraparound at 64K 3158 * on 16 bit machines and because stored blocks are restricted to 3159 * 64K-1 bytes. 3160 */ 3161 } 3162 #endif 3163 3164 /* =========================================================================== 3165 * Send the block data compressed using the given Huffman trees 3166 */ 3167 local void compress_block(deflate_state *s, 3168 const ct_data *ltree, /* literal tree */ 3169 const ct_data *dtree) /* distance tree */ 3170 { 3171 unsigned dist; /* distance of matched string */ 3172 int lc; /* match length or unmatched char (if dist == 0) */ 3173 unsigned lx = 0; /* running index in l_buf */ 3174 unsigned code; /* the code to send */ 3175 int extra; /* number of extra bits to send */ 3176 3177 if (s->last_lit != 0) do { 3178 dist = s->d_buf[lx]; 3179 lc = s->l_buf[lx++]; 3180 if (dist == 0) { 3181 send_code(s, lc, ltree); /* send a literal byte */ 3182 Tracecv(isgraph(lc), (stderr," '%c' ", lc)); 3183 } else { 3184 /* Here, lc is the match length - MIN_MATCH */ 3185 code = _length_code[lc]; 3186 send_code(s, code+LITERALS+1, ltree); /* send the length code */ 3187 extra = extra_lbits[code]; 3188 if (extra != 0) { 3189 lc -= base_length[code]; 3190 send_bits(s, lc, extra); /* send the extra length bits */ 3191 } 3192 dist--; /* dist is now the match distance - 1 */ 3193 code = d_code(dist); 3194 Assert (code < D_CODES, "bad d_code"); 3195 3196 send_code(s, code, dtree); /* send the distance code */ 3197 extra = extra_dbits[code]; 3198 if (extra != 0) { 3199 dist -= base_dist[code]; 3200 send_bits(s, dist, extra); /* send the extra distance bits */ 3201 } 3202 } /* literal or match pair ? */ 3203 3204 /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */ 3205 Assert(s->pending < s->lit_bufsize + 2*lx, "pendingBuf overflow"); 3206 3207 } while (lx < s->last_lit); 3208 3209 send_code(s, END_BLOCK, ltree); 3210 s->last_eob_len = ltree[END_BLOCK].Len; 3211 } 3212 3213 /* =========================================================================== 3214 * Set the data type to ASCII or BINARY, using a crude approximation: 3215 * binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise. 3216 * IN assertion: the fields freq of dyn_ltree are set and the total of all 3217 * frequencies does not exceed 64K (to fit in an int on 16 bit machines). 3218 */ 3219 local void set_data_type(deflate_state *s) 3220 { 3221 int n = 0; 3222 unsigned ascii_freq = 0; 3223 unsigned bin_freq = 0; 3224 while (n < 7) bin_freq += s->dyn_ltree[n++].Freq; 3225 while (n < 128) ascii_freq += s->dyn_ltree[n++].Freq; 3226 while (n < LITERALS) bin_freq += s->dyn_ltree[n++].Freq; 3227 s->data_type = (Byte)(bin_freq > (ascii_freq >> 2) ? Z_BINARY : Z_ASCII); 3228 } 3229 3230 /* =========================================================================== 3231 * Reverse the first len bits of a code, using straightforward code (a faster 3232 * method would use a table) 3233 * IN assertion: 1 <= len <= 15 3234 */ 3235 local unsigned bi_reverse(unsigned code, /* the value to invert */ 3236 int len) /* its bit length */ 3237 { 3238 unsigned res = 0; 3239 do { 3240 res |= code & 1; 3241 code >>= 1, res <<= 1; 3242 } while (--len > 0); 3243 return res >> 1; 3244 } 3245 3246 /* =========================================================================== 3247 * Flush the bit buffer, keeping at most 7 bits in it. 3248 */ 3249 local void bi_flush(deflate_state *s) 3250 { 3251 if (s->bi_valid == 16) { 3252 put_short(s, s->bi_buf); 3253 s->bi_buf = 0; 3254 s->bi_valid = 0; 3255 } else if (s->bi_valid >= 8) { 3256 put_byte(s, (Byte)s->bi_buf); 3257 s->bi_buf >>= 8; 3258 s->bi_valid -= 8; 3259 } 3260 } 3261 3262 /* =========================================================================== 3263 * Flush the bit buffer and align the output on a byte boundary 3264 */ 3265 local void bi_windup(deflate_state *s) 3266 { 3267 if (s->bi_valid > 8) { 3268 put_short(s, s->bi_buf); 3269 } else if (s->bi_valid > 0) { 3270 put_byte(s, (Byte)s->bi_buf); 3271 } 3272 s->bi_buf = 0; 3273 s->bi_valid = 0; 3274 #ifdef DEBUG_ZLIB 3275 s->bits_sent = (s->bits_sent+7) & ~7; 3276 #endif 3277 } 3278 3279 /* =========================================================================== 3280 * Copy a stored block, storing first the length and its 3281 * one's complement if requested. 3282 */ 3283 local void copy_block(deflate_state *s, 3284 charf *buf, /* the input data */ 3285 unsigned len, /* its length */ 3286 int header) /* true if block header must be written */ 3287 { 3288 bi_windup(s); /* align on byte boundary */ 3289 s->last_eob_len = 8; /* enough lookahead for inflate */ 3290 3291 if (header) { 3292 put_short(s, (ush)len); 3293 put_short(s, (ush)~len); 3294 #ifdef DEBUG_ZLIB 3295 s->bits_sent += 2*16; 3296 #endif 3297 } 3298 #ifdef DEBUG_ZLIB 3299 s->bits_sent += (ulg)len<<3; 3300 #endif 3301 /* bundle up the put_byte(s, *buf++) calls */ 3302 zmemcpy(&s->pending_buf[s->pending], buf, len); 3303 s->pending += len; 3304 } 3305 /* --- trees.c */ 3306 3307 /* +++ inflate.c */ 3308 3309 /* inflate.c -- zlib interface to inflate modules 3310 * Copyright (C) 1995-2002 Mark Adler 3311 * For conditions of distribution and use, see copyright notice in zlib.h 3312 */ 3313 3314 /* #include "zutil.h" */ 3315 3316 /* +++ infblock.h */ 3317 3318 /* infblock.h -- header to use infblock.c 3319 * Copyright (C) 1995-2002 Mark Adler 3320 * For conditions of distribution and use, see copyright notice in zlib.h 3321 */ 3322 3323 /* WARNING: this file should *not* be used by applications. It is 3324 part of the implementation of the compression library and is 3325 subject to change. Applications should only use zlib.h. 3326 */ 3327 3328 struct inflate_blocks_state; 3329 typedef struct inflate_blocks_state FAR inflate_blocks_statef; 3330 3331 extern inflate_blocks_statef * inflate_blocks_new( 3332 z_streamp z, 3333 check_func c, /* check function */ 3334 uInt w); /* window size */ 3335 3336 extern int inflate_blocks( 3337 inflate_blocks_statef *, 3338 z_streamp , 3339 int); /* initial return code */ 3340 3341 extern void inflate_blocks_reset( 3342 inflate_blocks_statef *, 3343 z_streamp , 3344 uLongf *); /* check value on output */ 3345 3346 extern int inflate_blocks_free( 3347 inflate_blocks_statef *, 3348 z_streamp); 3349 3350 extern void inflate_set_dictionary( 3351 inflate_blocks_statef *s, 3352 const Bytef *d, /* dictionary */ 3353 uInt n); /* dictionary length */ 3354 3355 extern int inflate_blocks_sync_point( 3356 inflate_blocks_statef *s); 3357 extern int inflate_addhistory( 3358 inflate_blocks_statef *, 3359 z_streamp); 3360 3361 extern int inflate_packet_flush( 3362 inflate_blocks_statef *); 3363 3364 /* --- infblock.h */ 3365 3366 #ifndef NO_DUMMY_DECL 3367 struct inflate_blocks_state {int dummy;}; /* for buggy compilers */ 3368 #endif 3369 3370 typedef enum { 3371 METHOD, /* waiting for method byte */ 3372 FLAG, /* waiting for flag byte */ 3373 DICT4, /* four dictionary check bytes to go */ 3374 DICT3, /* three dictionary check bytes to go */ 3375 DICT2, /* two dictionary check bytes to go */ 3376 DICT1, /* one dictionary check byte to go */ 3377 DICT0, /* waiting for inflateSetDictionary */ 3378 BLOCKS, /* decompressing blocks */ 3379 CHECK4, /* four check bytes to go */ 3380 CHECK3, /* three check bytes to go */ 3381 CHECK2, /* two check bytes to go */ 3382 CHECK1, /* one check byte to go */ 3383 DONE, /* finished check, done */ 3384 BAD} /* got an error--stay here */ 3385 inflate_mode; 3386 3387 /* inflate private state */ 3388 struct internal_state { 3389 3390 /* mode */ 3391 inflate_mode mode; /* current inflate mode */ 3392 3393 /* mode dependent information */ 3394 union { 3395 uInt method; /* if FLAGS, method byte */ 3396 struct { 3397 uLong was; /* computed check value */ 3398 uLong need; /* stream check value */ 3399 } check; /* if CHECK, check values to compare */ 3400 uInt marker; /* if BAD, inflateSync's marker bytes count */ 3401 } sub; /* submode */ 3402 3403 /* mode independent information */ 3404 int nowrap; /* flag for no wrapper */ 3405 uInt wbits; /* log2(window size) (8..15, defaults to 15) */ 3406 inflate_blocks_statef 3407 *blocks; /* current inflate_blocks state */ 3408 3409 }; 3410 3411 3412 int ZEXPORT inflateReset(z_streamp z) 3413 { 3414 if (z == Z_NULL || z->state == Z_NULL) 3415 return Z_STREAM_ERROR; 3416 z->total_in = z->total_out = 0; 3417 z->msg = Z_NULL; 3418 z->state->mode = z->state->nowrap ? BLOCKS : METHOD; 3419 inflate_blocks_reset(z->state->blocks, z, Z_NULL); 3420 Tracev((stderr, "inflate: reset\n")); 3421 return Z_OK; 3422 } 3423 3424 3425 int ZEXPORT inflateEnd(z_streamp z) 3426 { 3427 if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL) 3428 return Z_STREAM_ERROR; 3429 if (z->state->blocks != Z_NULL) 3430 inflate_blocks_free(z->state->blocks, z); 3431 ZFREE(z, z->state); 3432 z->state = Z_NULL; 3433 Tracev((stderr, "inflate: end\n")); 3434 return Z_OK; 3435 } 3436 3437 3438 int ZEXPORT inflateInit2_(z_streamp z, int w, const char *vers, int stream_size) 3439 { 3440 if (vers == Z_NULL || vers[0] != ZLIB_VERSION[0] || 3441 stream_size != sizeof(z_stream)) 3442 return Z_VERSION_ERROR; 3443 3444 /* initialize state */ 3445 if (z == Z_NULL) 3446 return Z_STREAM_ERROR; 3447 z->msg = Z_NULL; 3448 #ifndef NO_ZCFUNCS 3449 if (z->zalloc == Z_NULL) 3450 { 3451 z->zalloc = zcalloc; 3452 z->opaque = (voidpf)0; 3453 } 3454 if (z->zfree == Z_NULL) z->zfree = zcfree; 3455 #endif 3456 if ((z->state = (struct internal_state FAR *) 3457 ZALLOC(z,1,sizeof(struct internal_state))) == Z_NULL) 3458 return Z_MEM_ERROR; 3459 z->state->blocks = Z_NULL; 3460 3461 /* handle undocumented nowrap option (no zlib header or check) */ 3462 z->state->nowrap = 0; 3463 if (w < 0) 3464 { 3465 w = - w; 3466 z->state->nowrap = 1; 3467 } 3468 3469 /* set window size */ 3470 if (w < 8 || w > 15) 3471 { 3472 inflateEnd(z); 3473 return Z_STREAM_ERROR; 3474 } 3475 z->state->wbits = (uInt)w; 3476 3477 /* create inflate_blocks state */ 3478 if ((z->state->blocks = 3479 inflate_blocks_new(z, z->state->nowrap ? Z_NULL : adler32, (uInt)1 << w)) 3480 == Z_NULL) 3481 { 3482 inflateEnd(z); 3483 return Z_MEM_ERROR; 3484 } 3485 Tracev((stderr, "inflate: allocated\n")); 3486 3487 /* reset state */ 3488 inflateReset(z); 3489 return Z_OK; 3490 } 3491 3492 3493 #if 0 3494 int ZEXPORT inflateInit_(z_streamp z, const char *vers, int stream_size) 3495 { 3496 return inflateInit2_(z, DEF_WBITS, vers, stream_size); 3497 } 3498 #endif 3499 3500 3501 #define NEEDBYTE {if(z->avail_in==0)goto empty;r=Z_OK;} 3502 #define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++) 3503 3504 int ZEXPORT inflate(z_streamp z, int f) 3505 { 3506 int r, r2; 3507 uInt b; 3508 3509 if (z == Z_NULL || z->state == Z_NULL || z->next_in == Z_NULL) 3510 return Z_STREAM_ERROR; 3511 r2 = f == Z_FINISH ? Z_BUF_ERROR : Z_OK; 3512 r = Z_BUF_ERROR; 3513 while (1) switch (z->state->mode) 3514 { 3515 case METHOD: 3516 NEEDBYTE 3517 if (((z->state->sub.method = NEXTBYTE) & 0xf) != Z_DEFLATED) 3518 { 3519 z->state->mode = BAD; 3520 z->msg = "unknown compression method"; 3521 z->state->sub.marker = 5; /* can't try inflateSync */ 3522 break; 3523 } 3524 if ((z->state->sub.method >> 4) + 8 > z->state->wbits) 3525 { 3526 z->state->mode = BAD; 3527 z->msg = "invalid window size"; 3528 z->state->sub.marker = 5; /* can't try inflateSync */ 3529 break; 3530 } 3531 z->state->mode = FLAG; 3532 case FLAG: 3533 NEEDBYTE 3534 b = NEXTBYTE; 3535 if (((z->state->sub.method << 8) + b) % 31) 3536 { 3537 z->state->mode = BAD; 3538 z->msg = "incorrect header check"; 3539 z->state->sub.marker = 5; /* can't try inflateSync */ 3540 break; 3541 } 3542 Tracev((stderr, "inflate: zlib header ok\n")); 3543 if (!(b & PRESET_DICT)) 3544 { 3545 z->state->mode = BLOCKS; 3546 break; 3547 } 3548 z->state->mode = DICT4; 3549 case DICT4: 3550 NEEDBYTE 3551 z->state->sub.check.need = (uLong)NEXTBYTE << 24; 3552 z->state->mode = DICT3; 3553 case DICT3: 3554 NEEDBYTE 3555 z->state->sub.check.need += (uLong)NEXTBYTE << 16; 3556 z->state->mode = DICT2; 3557 case DICT2: 3558 NEEDBYTE 3559 z->state->sub.check.need += (uLong)NEXTBYTE << 8; 3560 z->state->mode = DICT1; 3561 case DICT1: 3562 NEEDBYTE 3563 z->state->sub.check.need += (uLong)NEXTBYTE; 3564 z->adler = z->state->sub.check.need; 3565 z->state->mode = DICT0; 3566 return Z_NEED_DICT; 3567 case DICT0: 3568 z->state->mode = BAD; 3569 z->msg = "need dictionary"; 3570 z->state->sub.marker = 0; /* can try inflateSync */ 3571 return Z_STREAM_ERROR; 3572 case BLOCKS: 3573 r = inflate_blocks(z->state->blocks, z, r); 3574 if (f == Z_PACKET_FLUSH && z->avail_in == 0 && z->avail_out != 0) 3575 r = inflate_packet_flush(z->state->blocks); 3576 if (r == Z_DATA_ERROR) 3577 { 3578 z->state->mode = BAD; 3579 z->state->sub.marker = 0; /* can try inflateSync */ 3580 break; 3581 } 3582 if (r == Z_OK) 3583 r = r2; 3584 if (r != Z_STREAM_END) 3585 return r; 3586 r = r2; 3587 inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was); 3588 if (z->state->nowrap) 3589 { 3590 z->state->mode = DONE; 3591 break; 3592 } 3593 z->state->mode = CHECK4; 3594 case CHECK4: 3595 NEEDBYTE 3596 z->state->sub.check.need = (uLong)NEXTBYTE << 24; 3597 z->state->mode = CHECK3; 3598 case CHECK3: 3599 NEEDBYTE 3600 z->state->sub.check.need += (uLong)NEXTBYTE << 16; 3601 z->state->mode = CHECK2; 3602 case CHECK2: 3603 NEEDBYTE 3604 z->state->sub.check.need += (uLong)NEXTBYTE << 8; 3605 z->state->mode = CHECK1; 3606 case CHECK1: 3607 NEEDBYTE 3608 z->state->sub.check.need += (uLong)NEXTBYTE; 3609 3610 if (z->state->sub.check.was != z->state->sub.check.need) 3611 { 3612 z->state->mode = BAD; 3613 z->msg = "incorrect data check"; 3614 z->state->sub.marker = 5; /* can't try inflateSync */ 3615 break; 3616 } 3617 Tracev((stderr, "inflate: zlib check ok\n")); 3618 z->state->mode = DONE; 3619 case DONE: 3620 return Z_STREAM_END; 3621 case BAD: 3622 return Z_DATA_ERROR; 3623 default: 3624 return Z_STREAM_ERROR; 3625 } 3626 empty: 3627 if (f != Z_PACKET_FLUSH) 3628 return r; 3629 z->state->mode = BAD; 3630 z->msg = "need more for packet flush"; 3631 z->state->sub.marker = 0; 3632 return Z_DATA_ERROR; 3633 } 3634 3635 3636 #if 0 3637 int ZEXPORT inflateSetDictionary(z_streamp z, 3638 const Bytef *dictionary, 3639 uInt dictLength) 3640 { 3641 uInt length = dictLength; 3642 3643 if (z == Z_NULL || z->state == Z_NULL || z->state->mode != DICT0) 3644 return Z_STREAM_ERROR; 3645 3646 if (adler32(1L, dictionary, dictLength) != z->adler) return Z_DATA_ERROR; 3647 z->adler = 1L; 3648 3649 if (length >= ((uInt)1<<z->state->wbits)) 3650 { 3651 length = (1<<z->state->wbits)-1; 3652 dictionary += dictLength - length; 3653 } 3654 inflate_set_dictionary(z->state->blocks, dictionary, length); 3655 z->state->mode = BLOCKS; 3656 return Z_OK; 3657 } 3658 #endif 3659 3660 /* 3661 * This subroutine adds the data at next_in/avail_in to the output history 3662 * without performing any output. The output buffer must be "caught up"; 3663 * i.e. no pending output (hence s->read equals s->write), and the state must 3664 * be BLOCKS (i.e. we should be willing to see the start of a series of 3665 * BLOCKS). On exit, the output will also be caught up, and the checksum 3666 * will have been updated if need be. 3667 */ 3668 3669 int inflateIncomp(z_stream *z) 3670 { 3671 if (z->state->mode != BLOCKS) 3672 return Z_DATA_ERROR; 3673 return inflate_addhistory(z->state->blocks, z); 3674 } 3675 3676 #if 0 3677 int ZEXPORT inflateSync(z) 3678 z_streamp z; 3679 { 3680 uInt n; /* number of bytes to look at */ 3681 Bytef *p; /* pointer to bytes */ 3682 uInt m; /* number of marker bytes found in a row */ 3683 uLong r, w; /* temporaries to save total_in and total_out */ 3684 3685 /* set up */ 3686 if (z == Z_NULL || z->state == Z_NULL) 3687 return Z_STREAM_ERROR; 3688 if (z->state->mode != BAD) 3689 { 3690 z->state->mode = BAD; 3691 z->state->sub.marker = 0; 3692 } 3693 if ((n = z->avail_in) == 0) 3694 return Z_BUF_ERROR; 3695 p = z->next_in; 3696 m = z->state->sub.marker; 3697 3698 /* search */ 3699 while (n && m < 4) 3700 { 3701 static const Byte mark[4] = {0, 0, 0xff, 0xff}; 3702 if (*p == mark[m]) 3703 m++; 3704 else if (*p) 3705 m = 0; 3706 else 3707 m = 4 - m; 3708 p++, n--; 3709 } 3710 3711 /* restore */ 3712 z->total_in += p - z->next_in; 3713 z->next_in = p; 3714 z->avail_in = n; 3715 z->state->sub.marker = m; 3716 3717 /* return no joy or set up to restart on a new block */ 3718 if (m != 4) 3719 return Z_DATA_ERROR; 3720 r = z->total_in; w = z->total_out; 3721 inflateReset(z); 3722 z->total_in = r; z->total_out = w; 3723 z->state->mode = BLOCKS; 3724 return Z_OK; 3725 } 3726 #endif 3727 3728 3729 /* Returns true if inflate is currently at the end of a block generated 3730 * by Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP 3731 * implementation to provide an additional safety check. PPP uses Z_SYNC_FLUSH 3732 * but removes the length bytes of the resulting empty stored block. When 3733 * decompressing, PPP checks that at the end of input packet, inflate is 3734 * waiting for these length bytes. 3735 */ 3736 #if 0 3737 int ZEXPORT inflateSyncPoint(z) 3738 z_streamp z; 3739 { 3740 if (z == Z_NULL || z->state == Z_NULL || z->state->blocks == Z_NULL) 3741 return Z_STREAM_ERROR; 3742 return inflate_blocks_sync_point(z->state->blocks); 3743 } 3744 #endif 3745 #undef NEEDBYTE 3746 #undef NEXTBYTE 3747 /* --- inflate.c */ 3748 3749 /* +++ infblock.c */ 3750 3751 /* infblock.c -- interpret and process block types to last block 3752 * Copyright (C) 1995-2002 Mark Adler 3753 * For conditions of distribution and use, see copyright notice in zlib.h 3754 */ 3755 3756 /* #include "zutil.h" */ 3757 /* #include "infblock.h" */ 3758 3759 /* +++ inftrees.h */ 3760 3761 /* inftrees.h -- header to use inftrees.c 3762 * Copyright (C) 1995-2002 Mark Adler 3763 * For conditions of distribution and use, see copyright notice in zlib.h 3764 */ 3765 3766 /* WARNING: this file should *not* be used by applications. It is 3767 part of the implementation of the compression library and is 3768 subject to change. Applications should only use zlib.h. 3769 */ 3770 3771 /* Huffman code lookup table entry--this entry is four bytes for machines 3772 that have 16-bit pointers (e.g. PC's in the small or medium model). */ 3773 3774 typedef struct inflate_huft_s FAR inflate_huft; 3775 3776 struct inflate_huft_s { 3777 union { 3778 struct { 3779 Byte Exop; /* number of extra bits or operation */ 3780 Byte Bits; /* number of bits in this code or subcode */ 3781 } what; 3782 uInt pad; /* pad structure to a power of 2 (4 bytes for */ 3783 } word; /* 16-bit, 8 bytes for 32-bit int's) */ 3784 uInt base; /* literal, length base, distance base, 3785 or table offset */ 3786 }; 3787 3788 /* Maximum size of dynamic tree. The maximum found in a long but non- 3789 exhaustive search was 1004 huft structures (850 for length/literals 3790 and 154 for distances, the latter actually the result of an 3791 exhaustive search). The actual maximum is not known, but the 3792 value below is more than safe. */ 3793 #define MANY 1440 3794 3795 extern int inflate_trees_bits( 3796 uIntf *, /* 19 code lengths */ 3797 uIntf *, /* bits tree desired/actual depth */ 3798 inflate_huft * FAR *, /* bits tree result */ 3799 inflate_huft *, /* space for trees */ 3800 z_streamp); /* for messages */ 3801 3802 extern int inflate_trees_dynamic( 3803 uInt, /* number of literal/length codes */ 3804 uInt, /* number of distance codes */ 3805 uIntf *, /* that many (total) code lengths */ 3806 uIntf *, /* literal desired/actual bit depth */ 3807 uIntf *, /* distance desired/actual bit depth */ 3808 inflate_huft * FAR *, /* literal/length tree result */ 3809 inflate_huft * FAR *, /* distance tree result */ 3810 inflate_huft *, /* space for trees */ 3811 z_streamp); /* for messages */ 3812 3813 extern int inflate_trees_fixed( 3814 uIntf *, /* literal desired/actual bit depth */ 3815 uIntf *, /* distance desired/actual bit depth */ 3816 inflate_huft * FAR *, /* literal/length tree result */ 3817 inflate_huft * FAR *, /* distance tree result */ 3818 z_streamp); /* for memory allocation */ 3819 /* --- inftrees.h */ 3820 3821 /* +++ infcodes.h */ 3822 3823 /* infcodes.h -- header to use infcodes.c 3824 * Copyright (C) 1995-2002 Mark Adler 3825 * For conditions of distribution and use, see copyright notice in zlib.h 3826 */ 3827 3828 /* WARNING: this file should *not* be used by applications. It is 3829 part of the implementation of the compression library and is 3830 subject to change. Applications should only use zlib.h. 3831 */ 3832 3833 struct inflate_codes_state; 3834 typedef struct inflate_codes_state FAR inflate_codes_statef; 3835 3836 extern inflate_codes_statef *inflate_codes_new( 3837 uInt, uInt, 3838 inflate_huft *, inflate_huft *, 3839 z_streamp ); 3840 3841 extern int inflate_codes( 3842 inflate_blocks_statef *, 3843 z_streamp , 3844 int); 3845 3846 extern void inflate_codes_free( 3847 inflate_codes_statef *, 3848 z_streamp ); 3849 3850 /* --- infcodes.h */ 3851 3852 /* +++ infutil.h */ 3853 3854 /* infutil.h -- types and macros common to blocks and codes 3855 * Copyright (C) 1995-2002 Mark Adler 3856 * For conditions of distribution and use, see copyright notice in zlib.h 3857 */ 3858 3859 /* WARNING: this file should *not* be used by applications. It is 3860 part of the implementation of the compression library and is 3861 subject to change. Applications should only use zlib.h. 3862 */ 3863 3864 #ifndef _INFUTIL_H 3865 #define _INFUTIL_H 3866 3867 typedef enum { 3868 TYPE, /* get type bits (3, including end bit) */ 3869 LENS, /* get lengths for stored */ 3870 STORED, /* processing stored block */ 3871 TABLE, /* get table lengths */ 3872 BTREE, /* get bit lengths tree for a dynamic block */ 3873 DTREE, /* get length, distance trees for a dynamic block */ 3874 CODES, /* processing fixed or dynamic block */ 3875 DRY, /* output remaining window bytes */ 3876 DONEB, /* finished last block, done */ 3877 BADB} /* got a data error--stuck here */ 3878 inflate_block_mode; 3879 3880 /* inflate blocks semi-private state */ 3881 struct inflate_blocks_state { 3882 3883 /* mode */ 3884 inflate_block_mode mode; /* current inflate_block mode */ 3885 3886 /* mode dependent information */ 3887 union { 3888 uInt left; /* if STORED, bytes left to copy */ 3889 struct { 3890 uInt table; /* table lengths (14 bits) */ 3891 uInt index; /* index into blens (or border) */ 3892 uIntf *blens; /* bit lengths of codes */ 3893 uInt bb; /* bit length tree depth */ 3894 inflate_huft *tb; /* bit length decoding tree */ 3895 } trees; /* if DTREE, decoding info for trees */ 3896 struct { 3897 inflate_codes_statef 3898 *codes; 3899 } decode; /* if CODES, current state */ 3900 } sub; /* submode */ 3901 uInt last; /* true if this block is the last block */ 3902 3903 /* mode independent information */ 3904 uInt bitk; /* bits in bit buffer */ 3905 uLong bitb; /* bit buffer */ 3906 inflate_huft *hufts; /* single malloc for tree space */ 3907 Bytef *window; /* sliding window */ 3908 Bytef *end; /* one byte after sliding window */ 3909 Bytef *read; /* window read pointer */ 3910 Bytef *write; /* window write pointer */ 3911 check_func checkfn; /* check function */ 3912 uLong check; /* check on output */ 3913 3914 }; 3915 3916 3917 /* defines for inflate input/output */ 3918 /* update pointers and return */ 3919 #define UPDBITS {s->bitb=b;s->bitk=k;} 3920 #define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;} 3921 #define UPDOUT {s->write=q;} 3922 #define UPDATE {UPDBITS UPDIN UPDOUT} 3923 #define LEAVE {UPDATE return inflate_flush(s,z,r);} 3924 /* get bytes and bits */ 3925 #define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;} 3926 #define NEEDBYTE {if(n)r=Z_OK;else LEAVE} 3927 #define NEXTBYTE (n--,*p++) 3928 #define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}} 3929 #define DUMPBITS(j) {b>>=(j);k-=(j);} 3930 /* output bytes */ 3931 #define WAVAIL (uInt)(q<s->read?s->read-q-1:s->end-q) 3932 #define LOADOUT {q=s->write;m=(uInt)WAVAIL;} 3933 #define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}} 3934 #define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT} 3935 #define NEEDOUT {if(m==0){WRAP if(m==0){FLUSH WRAP if(m==0) LEAVE}}r=Z_OK;} 3936 #define OUTBYTE(a) {*q++=(Byte)(a);m--;} 3937 /* load local pointers */ 3938 #define LOAD {LOADIN LOADOUT} 3939 3940 /* masks for lower bits (size given to avoid silly warnings with Visual C++) */ 3941 extern uInt inflate_mask[17]; 3942 3943 /* copy as much as possible from the sliding window to the output area */ 3944 extern int inflate_flush( 3945 inflate_blocks_statef *, 3946 z_streamp , 3947 int); 3948 3949 #ifndef NO_DUMMY_DECL 3950 struct internal_state {int dummy;}; /* for buggy compilers */ 3951 #endif 3952 3953 #endif 3954 /* --- infutil.h */ 3955 3956 #ifndef NO_DUMMY_DECL 3957 struct inflate_codes_state {int dummy;}; /* for buggy compilers */ 3958 #endif 3959 3960 /* simplify the use of the inflate_huft type with some defines */ 3961 #define exop word.what.Exop 3962 #define bits word.what.Bits 3963 3964 /* Table for deflate from PKZIP's appnote.txt. */ 3965 local const uInt border[] = { /* Order of the bit length code lengths */ 3966 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; 3967 3968 /* 3969 Notes beyond the 1.93a appnote.txt: 3970 3971 1. Distance pointers never point before the beginning of the output 3972 stream. 3973 2. Distance pointers can point back across blocks, up to 32k away. 3974 3. There is an implied maximum of 7 bits for the bit length table and 3975 15 bits for the actual data. 3976 4. If only one code exists, then it is encoded using one bit. (Zero 3977 would be more efficient, but perhaps a little confusing.) If two 3978 codes exist, they are coded using one bit each (0 and 1). 3979 5. There is no way of sending zero distance codes--a dummy must be 3980 sent if there are none. (History: a pre 2.0 version of PKZIP would 3981 store blocks with no distance codes, but this was discovered to be 3982 too harsh a criterion.) Valid only for 1.93a. 2.04c does allow 3983 zero distance codes, which is sent as one code of zero bits in 3984 length. 3985 6. There are up to 286 literal/length codes. Code 256 represents the 3986 end-of-block. Note however that the static length tree defines 3987 288 codes just to fill out the Huffman codes. Codes 286 and 287 3988 cannot be used though, since there is no length base or extra bits 3989 defined for them. Similarily, there are up to 30 distance codes. 3990 However, static trees define 32 codes (all 5 bits) to fill out the 3991 Huffman codes, but the last two had better not show up in the data. 3992 7. Unzip can check dynamic Huffman blocks for complete code sets. 3993 The exception is that a single code would not be complete (see #4). 3994 8. The five bits following the block type is really the number of 3995 literal codes sent minus 257. 3996 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits 3997 (1+6+6). Therefore, to output three times the length, you output 3998 three codes (1+1+1), whereas to output four times the same length, 3999 you only need two codes (1+3). Hmm. 4000 10. In the tree reconstruction algorithm, Code = Code + Increment 4001 only if BitLength(i) is not zero. (Pretty obvious.) 4002 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19) 4003 12. Note: length code 284 can represent 227-258, but length code 285 4004 really is 258. The last length deserves its own, short code 4005 since it gets used a lot in very redundant files. The length 4006 258 is special since 258 - 3 (the min match length) is 255. 4007 13. The literal/length and distance code bit lengths are read as a 4008 single stream of lengths. It is possible (and advantageous) for 4009 a repeat code (16, 17, or 18) to go across the boundary between 4010 the two sets of lengths. 4011 */ 4012 4013 4014 void inflate_blocks_reset(inflate_blocks_statef *s, z_streamp z, uLongf *c) 4015 { 4016 if (c != Z_NULL) 4017 *c = s->check; 4018 if (s->mode == BTREE || s->mode == DTREE) 4019 ZFREE(z, s->sub.trees.blens); 4020 if (s->mode == CODES) 4021 inflate_codes_free(s->sub.decode.codes, z); 4022 s->mode = TYPE; 4023 s->bitk = 0; 4024 s->bitb = 0; 4025 s->read = s->write = s->window; 4026 if (s->checkfn != Z_NULL) 4027 z->adler = s->check = (*s->checkfn)(0L, (const Bytef *)Z_NULL, 0); 4028 Tracev((stderr, "inflate: blocks reset\n")); 4029 } 4030 4031 4032 inflate_blocks_statef *inflate_blocks_new(z_streamp z, check_func c, uInt w) 4033 { 4034 inflate_blocks_statef *s; 4035 4036 if ((s = (inflate_blocks_statef *)ZALLOC 4037 (z,1,sizeof(struct inflate_blocks_state))) == Z_NULL) 4038 return s; 4039 if ((s->hufts = 4040 (inflate_huft *)ZALLOC(z, sizeof(inflate_huft), MANY)) == Z_NULL) 4041 { 4042 ZFREE(z, s); 4043 return Z_NULL; 4044 } 4045 if ((s->window = (Bytef *)ZALLOC(z, 1, w)) == Z_NULL) 4046 { 4047 ZFREE(z, s->hufts); 4048 ZFREE(z, s); 4049 return Z_NULL; 4050 } 4051 s->end = s->window + w; 4052 s->checkfn = c; 4053 s->mode = TYPE; 4054 Tracev((stderr, "inflate: blocks allocated\n")); 4055 inflate_blocks_reset(s, z, Z_NULL); 4056 return s; 4057 } 4058 4059 4060 int inflate_blocks(inflate_blocks_statef *s, z_streamp z, int r) 4061 { 4062 uInt t; /* temporary storage */ 4063 uLong b; /* bit buffer */ 4064 uInt k; /* bits in bit buffer */ 4065 Bytef *p; /* input data pointer */ 4066 uInt n; /* bytes available there */ 4067 Bytef *q; /* output window write pointer */ 4068 uInt m; /* bytes to end of window or read pointer */ 4069 4070 /* copy input/output information to locals (UPDATE macro restores) */ 4071 LOAD 4072 4073 /* process input based on current state */ 4074 while (1) switch (s->mode) 4075 { 4076 case TYPE: 4077 NEEDBITS(3) 4078 t = (uInt)b & 7; 4079 s->last = t & 1; 4080 switch (t >> 1) 4081 { 4082 case 0: /* stored */ 4083 Tracev((stderr, "inflate: stored block%s\n", 4084 s->last ? " (last)" : "")); 4085 DUMPBITS(3) 4086 t = k & 7; /* go to byte boundary */ 4087 DUMPBITS(t) 4088 s->mode = LENS; /* get length of stored block */ 4089 break; 4090 case 1: /* fixed */ 4091 Tracev((stderr, "inflate: fixed codes block%s\n", 4092 s->last ? " (last)" : "")); 4093 { 4094 uInt bl, bd; 4095 inflate_huft *tl, *td; 4096 4097 inflate_trees_fixed(&bl, &bd, &tl, &td, z); 4098 s->sub.decode.codes = inflate_codes_new(bl, bd, tl, td, z); 4099 if (s->sub.decode.codes == Z_NULL) 4100 { 4101 r = Z_MEM_ERROR; 4102 LEAVE 4103 } 4104 } 4105 DUMPBITS(3) 4106 s->mode = CODES; 4107 break; 4108 case 2: /* dynamic */ 4109 Tracev((stderr, "inflate: dynamic codes block%s\n", 4110 s->last ? " (last)" : "")); 4111 DUMPBITS(3) 4112 s->mode = TABLE; 4113 break; 4114 case 3: /* illegal */ 4115 DUMPBITS(3) 4116 s->mode = BADB; 4117 z->msg = "invalid block type"; 4118 r = Z_DATA_ERROR; 4119 LEAVE 4120 } 4121 break; 4122 case LENS: 4123 NEEDBITS(32) 4124 if ((((~b) >> 16) & 0xffff) != (b & 0xffff)) 4125 { 4126 s->mode = BADB; 4127 z->msg = "invalid stored block lengths"; 4128 r = Z_DATA_ERROR; 4129 LEAVE 4130 } 4131 s->sub.left = (uInt)b & 0xffff; 4132 b = k = 0; /* dump bits */ 4133 Tracev((stderr, "inflate: stored length %u\n", s->sub.left)); 4134 s->mode = s->sub.left ? STORED : (s->last ? DRY : TYPE); 4135 break; 4136 case STORED: 4137 if (n == 0) 4138 LEAVE 4139 NEEDOUT 4140 t = s->sub.left; 4141 if (t > n) t = n; 4142 if (t > m) t = m; 4143 zmemcpy(q, p, t); 4144 p += t; n -= t; 4145 q += t; m -= t; 4146 if ((s->sub.left -= t) != 0) 4147 break; 4148 Tracev((stderr, "inflate: stored end, %lu total out\n", 4149 z->total_out + (q >= s->read ? q - s->read : 4150 (s->end - s->read) + (q - s->window)))); 4151 s->mode = s->last ? DRY : TYPE; 4152 break; 4153 case TABLE: 4154 NEEDBITS(14) 4155 s->sub.trees.table = t = (uInt)b & 0x3fff; 4156 #ifndef PKZIP_BUG_WORKAROUND 4157 if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29) 4158 { 4159 s->mode = BADB; 4160 z->msg = "too many length or distance symbols"; 4161 r = Z_DATA_ERROR; 4162 LEAVE 4163 } 4164 #endif 4165 t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f); 4166 if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL) 4167 { 4168 r = Z_MEM_ERROR; 4169 LEAVE 4170 } 4171 DUMPBITS(14) 4172 s->sub.trees.index = 0; 4173 Tracev((stderr, "inflate: table sizes ok\n")); 4174 s->mode = BTREE; 4175 case BTREE: 4176 while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10)) 4177 { 4178 NEEDBITS(3) 4179 s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7; 4180 DUMPBITS(3) 4181 } 4182 while (s->sub.trees.index < 19) 4183 s->sub.trees.blens[border[s->sub.trees.index++]] = 0; 4184 s->sub.trees.bb = 7; 4185 t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb, 4186 &s->sub.trees.tb, s->hufts, z); 4187 if (t != Z_OK) 4188 { 4189 r = t; 4190 if (r == Z_DATA_ERROR) 4191 { 4192 ZFREE(z, s->sub.trees.blens); 4193 s->mode = BADB; 4194 } 4195 LEAVE 4196 } 4197 s->sub.trees.index = 0; 4198 Tracev((stderr, "inflate: bits tree ok\n")); 4199 s->mode = DTREE; 4200 case DTREE: 4201 while (t = s->sub.trees.table, 4202 s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f)) 4203 { 4204 inflate_huft *h; 4205 uInt i, j, c; 4206 4207 t = s->sub.trees.bb; 4208 NEEDBITS(t) 4209 h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]); 4210 t = h->bits; 4211 c = h->base; 4212 if (c < 16) 4213 { 4214 DUMPBITS(t) 4215 s->sub.trees.blens[s->sub.trees.index++] = c; 4216 } 4217 else /* c == 16..18 */ 4218 { 4219 i = c == 18 ? 7 : c - 14; 4220 j = c == 18 ? 11 : 3; 4221 NEEDBITS(t + i) 4222 DUMPBITS(t) 4223 j += (uInt)b & inflate_mask[i]; 4224 DUMPBITS(i) 4225 i = s->sub.trees.index; 4226 t = s->sub.trees.table; 4227 if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) || 4228 (c == 16 && i < 1)) 4229 { 4230 ZFREE(z, s->sub.trees.blens); 4231 s->mode = BADB; 4232 z->msg = "invalid bit length repeat"; 4233 r = Z_DATA_ERROR; 4234 LEAVE 4235 } 4236 c = c == 16 ? s->sub.trees.blens[i - 1] : 0; 4237 do { 4238 s->sub.trees.blens[i++] = c; 4239 } while (--j); 4240 s->sub.trees.index = i; 4241 } 4242 } 4243 s->sub.trees.tb = Z_NULL; 4244 { 4245 uInt bl, bd; 4246 inflate_huft *tl, *td; 4247 inflate_codes_statef *c; 4248 4249 bl = 9; /* must be <= 9 for lookahead assumptions */ 4250 bd = 6; /* must be <= 9 for lookahead assumptions */ 4251 t = s->sub.trees.table; 4252 t = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f), 4253 s->sub.trees.blens, &bl, &bd, &tl, &td, 4254 s->hufts, z); 4255 if (t != Z_OK) 4256 { 4257 if (t == (uInt)Z_DATA_ERROR) 4258 { 4259 ZFREE(z, s->sub.trees.blens); 4260 s->mode = BADB; 4261 } 4262 r = t; 4263 LEAVE 4264 } 4265 Tracev((stderr, "inflate: trees ok\n")); 4266 if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL) 4267 { 4268 r = Z_MEM_ERROR; 4269 LEAVE 4270 } 4271 s->sub.decode.codes = c; 4272 } 4273 ZFREE(z, s->sub.trees.blens); 4274 s->mode = CODES; 4275 case CODES: 4276 UPDATE 4277 if ((r = inflate_codes(s, z, r)) != Z_STREAM_END) 4278 return inflate_flush(s, z, r); 4279 r = Z_OK; 4280 inflate_codes_free(s->sub.decode.codes, z); 4281 LOAD 4282 Tracev((stderr, "inflate: codes end, %lu total out\n", 4283 z->total_out + (q >= s->read ? q - s->read : 4284 (s->end - s->read) + (q - s->window)))); 4285 if (!s->last) 4286 { 4287 s->mode = TYPE; 4288 break; 4289 } 4290 s->mode = DRY; 4291 case DRY: 4292 FLUSH 4293 if (s->read != s->write) 4294 LEAVE 4295 s->mode = DONEB; 4296 case DONEB: 4297 r = Z_STREAM_END; 4298 LEAVE 4299 case BADB: 4300 r = Z_DATA_ERROR; 4301 LEAVE 4302 default: 4303 r = Z_STREAM_ERROR; 4304 LEAVE 4305 } 4306 } 4307 4308 4309 int inflate_blocks_free(inflate_blocks_statef *s, z_streamp z) 4310 { 4311 inflate_blocks_reset(s, z, Z_NULL); 4312 ZFREE(z, s->window); 4313 ZFREE(z, s->hufts); 4314 ZFREE(z, s); 4315 Tracev((stderr, "inflate: blocks freed\n")); 4316 return Z_OK; 4317 } 4318 4319 4320 #if 0 4321 void inflate_set_dictionary(inflate_blocks_statef *s, const Bytef *d, uInt n) 4322 { 4323 zmemcpy(s->window, d, n); 4324 s->read = s->write = s->window + n; 4325 } 4326 #endif 4327 4328 /* 4329 * This subroutine adds the data at next_in/avail_in to the output history 4330 * without performing any output. The output buffer must be "caught up"; 4331 * i.e. no pending output (hence s->read equals s->write), and the state must 4332 * be BLOCKS (i.e. we should be willing to see the start of a series of 4333 * BLOCKS). On exit, the output will also be caught up, and the checksum 4334 * will have been updated if need be. 4335 */ 4336 int inflate_addhistory(inflate_blocks_statef *s, z_stream *z) 4337 { 4338 uLong b; /* bit buffer */ /* NOT USED HERE */ 4339 uInt k; /* bits in bit buffer */ /* NOT USED HERE */ 4340 uInt t; /* temporary storage */ 4341 Bytef *p; /* input data pointer */ 4342 uInt n; /* bytes available there */ 4343 Bytef *q; /* output window write pointer */ 4344 uInt m; /* bytes to end of window or read pointer */ 4345 4346 if (s->read != s->write) 4347 return Z_STREAM_ERROR; 4348 if (s->mode != TYPE) 4349 return Z_DATA_ERROR; 4350 4351 /* we're ready to rock */ 4352 LOAD 4353 /* while there is input ready, copy to output buffer, moving 4354 * pointers as needed. 4355 */ 4356 while (n) { 4357 t = n; /* how many to do */ 4358 /* is there room until end of buffer? */ 4359 if (t > m) t = m; 4360 /* update check information */ 4361 if (s->checkfn != Z_NULL) 4362 s->check = (*s->checkfn)(s->check, q, t); 4363 zmemcpy(q, p, t); 4364 q += t; 4365 p += t; 4366 n -= t; 4367 z->total_out += t; 4368 s->read = q; /* drag read pointer forward */ 4369 /* WWRAP */ /* expand WWRAP macro by hand to handle s->read */ 4370 if (q == s->end) { 4371 s->read = q = s->window; 4372 m = WAVAIL; 4373 } 4374 } 4375 UPDATE 4376 return Z_OK; 4377 } 4378 4379 4380 /* 4381 * At the end of a Deflate-compressed PPP packet, we expect to have seen 4382 * a `stored' block type value but not the (zero) length bytes. 4383 */ 4384 int inflate_packet_flush(inflate_blocks_statef *s) 4385 { 4386 if (s->mode != LENS) 4387 return Z_DATA_ERROR; 4388 s->mode = TYPE; 4389 return Z_OK; 4390 } 4391 4392 /* Returns true if inflate is currently at the end of a block generated 4393 * by Z_SYNC_FLUSH or Z_FULL_FLUSH. 4394 * IN assertion: s != Z_NULL 4395 */ 4396 #if 0 4397 int inflate_blocks_sync_point(s) 4398 inflate_blocks_statef *s; 4399 { 4400 return s->mode == LENS; 4401 } 4402 #endif 4403 /* --- infblock.c */ 4404 4405 4406 /* +++ inftrees.c */ 4407 4408 /* inftrees.c -- generate Huffman trees for efficient decoding 4409 * Copyright (C) 1995-2002 Mark Adler 4410 * For conditions of distribution and use, see copyright notice in zlib.h 4411 */ 4412 4413 /* #include "zutil.h" */ 4414 /* #include "inftrees.h" */ 4415 4416 #if !defined(BUILDFIXED) && !defined(STDC) 4417 # define BUILDFIXED /* non ANSI compilers may not accept inffixed.h */ 4418 #endif 4419 4420 const char inflate_copyright[] = 4421 " inflate 1.1.4 Copyright 1995-2002 Mark Adler "; 4422 /* 4423 If you use the zlib library in a product, an acknowledgment is welcome 4424 in the documentation of your product. If for some reason you cannot 4425 include such an acknowledgment, I would appreciate that you keep this 4426 copyright string in the executable of your product. 4427 */ 4428 4429 #ifndef NO_DUMMY_DECL 4430 struct internal_state {int dummy;}; /* for buggy compilers */ 4431 #endif 4432 4433 /* simplify the use of the inflate_huft type with some defines */ 4434 #define exop word.what.Exop 4435 #define bits word.what.Bits 4436 4437 4438 local int huft_build( 4439 uIntf *, /* code lengths in bits */ 4440 uInt, /* number of codes */ 4441 uInt, /* number of "simple" codes */ 4442 const uIntf *, /* list of base values for non-simple codes */ 4443 const uIntf *, /* list of extra bits for non-simple codes */ 4444 inflate_huft * FAR*,/* result: starting table */ 4445 uIntf *, /* maximum lookup bits (returns actual) */ 4446 inflate_huft *, /* space for trees */ 4447 uInt *, /* hufts used in space */ 4448 uIntf * ); /* space for values */ 4449 4450 /* Tables for deflate from PKZIP's appnote.txt. */ 4451 local const uInt cplens[31] = { /* Copy lengths for literal codes 257..285 */ 4452 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, 4453 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0}; 4454 /* see note #13 above about 258 */ 4455 local const uInt cplext[31] = { /* Extra bits for literal codes 257..285 */ 4456 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 4457 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 112, 112}; /* 112==invalid */ 4458 local const uInt cpdist[30] = { /* Copy offsets for distance codes 0..29 */ 4459 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, 4460 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145, 4461 8193, 12289, 16385, 24577}; 4462 local const uInt cpdext[30] = { /* Extra bits for distance codes */ 4463 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 4464 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 4465 12, 12, 13, 13}; 4466 4467 /* 4468 Huffman code decoding is performed using a multi-level table lookup. 4469 The fastest way to decode is to simply build a lookup table whose 4470 size is determined by the longest code. However, the time it takes 4471 to build this table can also be a factor if the data being decoded 4472 is not very long. The most common codes are necessarily the 4473 shortest codes, so those codes dominate the decoding time, and hence 4474 the speed. The idea is you can have a shorter table that decodes the 4475 shorter, more probable codes, and then point to subsidiary tables for 4476 the longer codes. The time it costs to decode the longer codes is 4477 then traded against the time it takes to make longer tables. 4478 4479 This results of this trade are in the variables lbits and dbits 4480 below. lbits is the number of bits the first level table for literal/ 4481 length codes can decode in one step, and dbits is the same thing for 4482 the distance codes. Subsequent tables are also less than or equal to 4483 those sizes. These values may be adjusted either when all of the 4484 codes are shorter than that, in which case the longest code length in 4485 bits is used, or when the shortest code is *longer* than the requested 4486 table size, in which case the length of the shortest code in bits is 4487 used. 4488 4489 There are two different values for the two tables, since they code a 4490 different number of possibilities each. The literal/length table 4491 codes 286 possible values, or in a flat code, a little over eight 4492 bits. The distance table codes 30 possible values, or a little less 4493 than five bits, flat. The optimum values for speed end up being 4494 about one bit more than those, so lbits is 8+1 and dbits is 5+1. 4495 The optimum values may differ though from machine to machine, and 4496 possibly even between compilers. Your mileage may vary. 4497 */ 4498 4499 4500 /* If BMAX needs to be larger than 16, then h and x[] should be uLong. */ 4501 #define BMAX 15 /* maximum bit length of any code */ 4502 4503 local int huft_build(uIntf *b, /* code lengths in bits (all assumed <= BMAX) */ 4504 uInt n, /* number of codes (assumed <= 288) */ 4505 uInt s, /* number of simple-valued codes (0..s-1) */ 4506 const uIntf *d, /* list of base values for non-simple codes */ 4507 const uIntf *e, /* list of extra bits for non-simple codes */ 4508 inflate_huft * FAR *t, /* result: starting table */ 4509 uIntf *m, /* maximum lookup bits, returns actual */ 4510 inflate_huft *hp, /* space for trees */ 4511 uInt *hn, /* hufts used in space */ 4512 uIntf *v) /* working area: values in order of bit length */ 4513 4514 /* Given a list of code lengths and a maximum table size, make a set of 4515 tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR 4516 if the given code set is incomplete (the tables are still built in this 4517 case), or Z_DATA_ERROR if the input is invalid. */ 4518 { 4519 4520 uInt a; /* counter for codes of length k */ 4521 uInt c[BMAX+1]; /* bit length count table */ 4522 uInt f; /* i repeats in table every f entries */ 4523 int g; /* maximum code length */ 4524 int h; /* table level */ 4525 uInt i; /* counter, current code */ 4526 uInt j; /* counter */ 4527 int k; /* number of bits in current code */ 4528 int l; /* bits per table (returned in m) */ 4529 uInt mask; /* (1 << w) - 1, to avoid cc -O bug on HP */ 4530 uIntf *p; /* pointer into c[], b[], or v[] */ 4531 inflate_huft *q; /* points to current table */ 4532 struct inflate_huft_s r; /* table entry for structure assignment */ 4533 inflate_huft *u[BMAX]; /* table stack */ 4534 int w; /* bits before this table == (l * h) */ 4535 uInt x[BMAX+1]; /* bit offsets, then code stack */ 4536 uIntf *xp; /* pointer into x */ 4537 int y; /* number of dummy codes added */ 4538 uInt z; /* number of entries in current table */ 4539 4540 r.base = 0; /* XXX gcc */ 4541 4542 /* Generate counts for each bit length */ 4543 p = c; 4544 #define C0 *p++ = 0; 4545 #define C2 C0 C0 C0 C0 4546 #define C4 C2 C2 C2 C2 4547 C4 /* clear c[]--assume BMAX+1 is 16 */ 4548 p = b; i = n; 4549 do { 4550 c[*p++]++; /* assume all entries <= BMAX */ 4551 } while (--i); 4552 if (c[0] == n) /* null input--all zero length codes */ 4553 { 4554 *t = (inflate_huft *)Z_NULL; 4555 *m = 0; 4556 return Z_OK; 4557 } 4558 4559 4560 /* Find minimum and maximum length, bound *m by those */ 4561 l = *m; 4562 for (j = 1; j <= BMAX; j++) 4563 if (c[j]) 4564 break; 4565 k = j; /* minimum code length */ 4566 if ((uInt)l < j) 4567 l = j; 4568 for (i = BMAX; i; i--) 4569 if (c[i]) 4570 break; 4571 g = i; /* maximum code length */ 4572 if ((uInt)l > i) 4573 l = i; 4574 *m = l; 4575 4576 4577 /* Adjust last length count to fill out codes, if needed */ 4578 for (y = 1 << j; j < i; j++, y <<= 1) 4579 if ((y -= c[j]) < 0) 4580 return Z_DATA_ERROR; 4581 if ((y -= c[i]) < 0) 4582 return Z_DATA_ERROR; 4583 c[i] += y; 4584 4585 4586 /* Generate starting offsets into the value table for each length */ 4587 x[1] = j = 0; 4588 p = c + 1; xp = x + 2; 4589 while (--i) { /* note that i == g from above */ 4590 *xp++ = (j += *p++); 4591 } 4592 4593 4594 /* Make a table of values in order of bit lengths */ 4595 p = b; i = 0; 4596 do { 4597 if ((j = *p++) != 0) 4598 v[x[j]++] = i; 4599 } while (++i < n); 4600 n = x[g]; /* set n to length of v */ 4601 4602 4603 /* Generate the Huffman codes and for each, make the table entries */ 4604 x[0] = i = 0; /* first Huffman code is zero */ 4605 p = v; /* grab values in bit order */ 4606 h = -1; /* no tables yet--level -1 */ 4607 w = -l; /* bits decoded == (l * h) */ 4608 u[0] = (inflate_huft *)Z_NULL; /* just to keep compilers happy */ 4609 q = (inflate_huft *)Z_NULL; /* ditto */ 4610 z = 0; /* ditto */ 4611 4612 /* go through the bit lengths (k already is bits in shortest code) */ 4613 for (; k <= g; k++) 4614 { 4615 a = c[k]; 4616 while (a--) 4617 { 4618 /* here i is the Huffman code of length k bits for value *p */ 4619 /* make tables up to required level */ 4620 while (k > w + l) 4621 { 4622 h++; 4623 w += l; /* previous table always l bits */ 4624 4625 /* compute minimum size table less than or equal to l bits */ 4626 z = g - w; 4627 z = z > (uInt)l ? l : z; /* table size upper limit */ 4628 if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */ 4629 { /* too few codes for k-w bit table */ 4630 f -= a + 1; /* deduct codes from patterns left */ 4631 xp = c + k; 4632 if (j < z) 4633 while (++j < z) /* try smaller tables up to z bits */ 4634 { 4635 if ((f <<= 1) <= *++xp) 4636 break; /* enough codes to use up j bits */ 4637 f -= *xp; /* else deduct codes from patterns */ 4638 } 4639 } 4640 z = 1 << j; /* table entries for j-bit table */ 4641 4642 /* allocate new table */ 4643 if (*hn + z > MANY) /* (note: doesn't matter for fixed) */ 4644 return Z_DATA_ERROR; /* overflow of MANY */ 4645 u[h] = q = hp + *hn; 4646 *hn += z; 4647 4648 /* connect to last table, if there is one */ 4649 if (h) 4650 { 4651 x[h] = i; /* save pattern for backing up */ 4652 r.bits = (Byte)l; /* bits to dump before this table */ 4653 r.exop = (Byte)j; /* bits in this table */ 4654 j = i >> (w - l); 4655 r.base = (uInt)(q - u[h-1] - j); /* offset to this table */ 4656 u[h-1][j] = r; /* connect to last table */ 4657 } 4658 else 4659 *t = q; /* first table is returned result */ 4660 } 4661 4662 /* set up table entry in r */ 4663 r.bits = (Byte)(k - w); 4664 if (p >= v + n) 4665 r.exop = 128 + 64; /* out of values--invalid code */ 4666 else if (*p < s) 4667 { 4668 r.exop = (Byte)(*p < 256 ? 0 : 32 + 64); /* 256 is end-of-block */ 4669 r.base = *p++; /* simple code is just the value */ 4670 } 4671 else 4672 { 4673 r.exop = (Byte)(e[*p - s] + 16 + 64);/* non-simple--look up in lists */ 4674 r.base = d[*p++ - s]; 4675 } 4676 4677 /* fill code-like entries with r */ 4678 f = 1 << (k - w); 4679 for (j = i >> w; j < z; j += f) 4680 q[j] = r; 4681 4682 /* backwards increment the k-bit code i */ 4683 for (j = 1 << (k - 1); i & j; j >>= 1) 4684 i ^= j; 4685 i ^= j; 4686 4687 /* backup over finished tables */ 4688 mask = (1 << w) - 1; /* needed on HP, cc -O bug */ 4689 if (h == -1) 4690 return Z_BUF_ERROR; 4691 while ((i & mask) != x[h]) 4692 { 4693 h--; /* don't need to update q */ 4694 w -= l; 4695 mask = (1 << w) - 1; 4696 } 4697 } 4698 } 4699 4700 4701 /* Return Z_BUF_ERROR if we were given an incomplete table */ 4702 return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK; 4703 } 4704 4705 4706 int inflate_trees_bits(uIntf *c, /* 19 code lengths */ 4707 uIntf *bb, /* bits tree desired/actual depth */ 4708 inflate_huft * FAR *tb, /* bits tree result */ 4709 inflate_huft *hp, /* space for trees */ 4710 z_streamp z) /* for message */ 4711 { 4712 int r; 4713 uInt hn = 0; /* hufts used in space */ 4714 uIntf *v; /* work area for huft_build */ 4715 4716 if ((v = (uIntf*)ZALLOC(z, 19, sizeof(uInt))) == Z_NULL) 4717 return Z_MEM_ERROR; 4718 r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL, 4719 tb, bb, hp, &hn, v); 4720 if (r == Z_DATA_ERROR) 4721 z->msg = "oversubscribed dynamic bit lengths tree"; 4722 else if (r == Z_BUF_ERROR || *bb == 0) 4723 { 4724 z->msg = "incomplete dynamic bit lengths tree"; 4725 r = Z_DATA_ERROR; 4726 } 4727 ZFREE(z, v); 4728 return r; 4729 } 4730 4731 4732 int inflate_trees_dynamic(uInt nl, 4733 uInt nd, /* number of literal/length codes */ 4734 uIntf *c, /* number of distance codes */ 4735 uIntf *bl, /* that many (total) code lengths */ 4736 uIntf *bd, /* literal desired/actual bit depth */ 4737 inflate_huft * FAR *tl, /* literal/length tree result */ 4738 inflate_huft * FAR *td, /* distance tree result */ 4739 inflate_huft *hp, /* space for trees */ 4740 z_streamp z) /* for message */ 4741 { 4742 int r; 4743 uInt hn = 0; /* hufts used in space */ 4744 uIntf *v; /* work area for huft_build */ 4745 4746 /* allocate work area */ 4747 if ((v = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL) 4748 return Z_MEM_ERROR; 4749 4750 /* build literal/length tree */ 4751 r = huft_build(c, nl, 257, cplens, cplext, tl, bl, hp, &hn, v); 4752 if (r != Z_OK || *bl == 0) 4753 { 4754 if (r == Z_DATA_ERROR) 4755 z->msg = "oversubscribed literal/length tree"; 4756 else if (r != Z_MEM_ERROR) 4757 { 4758 z->msg = "incomplete literal/length tree"; 4759 r = Z_DATA_ERROR; 4760 } 4761 ZFREE(z, v); 4762 return r; 4763 } 4764 4765 /* build distance tree */ 4766 r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, hp, &hn, v); 4767 if (r != Z_OK || (*bd == 0 && nl > 257)) 4768 { 4769 if (r == Z_DATA_ERROR) 4770 z->msg = "oversubscribed distance tree"; 4771 else if (r == Z_BUF_ERROR) { 4772 #ifdef PKZIP_BUG_WORKAROUND 4773 r = Z_OK; 4774 } 4775 #else 4776 z->msg = "incomplete distance tree"; 4777 r = Z_DATA_ERROR; 4778 } 4779 else if (r != Z_MEM_ERROR) 4780 { 4781 z->msg = "empty distance tree with lengths"; 4782 r = Z_DATA_ERROR; 4783 } 4784 ZFREE(z, v); 4785 return r; 4786 #endif 4787 } 4788 4789 /* done */ 4790 ZFREE(z, v); 4791 return Z_OK; 4792 } 4793 4794 4795 /* build fixed tables only once--keep them here */ 4796 #ifdef BUILDFIXED 4797 local int fixed_built = 0; 4798 #define FIXEDH 544 /* number of hufts used by fixed tables */ 4799 local inflate_huft fixed_mem[FIXEDH]; 4800 local uInt fixed_bl; 4801 local uInt fixed_bd; 4802 local inflate_huft *fixed_tl; 4803 local inflate_huft *fixed_td; 4804 #else 4805 4806 /* +++ inffixed.h */ 4807 /* inffixed.h -- table for decoding fixed codes 4808 * Generated automatically by the maketree.c program 4809 */ 4810 4811 /* WARNING: this file should *not* be used by applications. It is 4812 part of the implementation of the compression library and is 4813 subject to change. Applications should only use zlib.h. 4814 */ 4815 4816 local uInt fixed_bl = 9; 4817 local uInt fixed_bd = 5; 4818 local inflate_huft fixed_tl[] = { 4819 {{{96,7}},256}, {{{0,8}},80}, {{{0,8}},16}, {{{84,8}},115}, 4820 {{{82,7}},31}, {{{0,8}},112}, {{{0,8}},48}, {{{0,9}},192}, 4821 {{{80,7}},10}, {{{0,8}},96}, {{{0,8}},32}, {{{0,9}},160}, 4822 {{{0,8}},0}, {{{0,8}},128}, {{{0,8}},64}, {{{0,9}},224}, 4823 {{{80,7}},6}, {{{0,8}},88}, {{{0,8}},24}, {{{0,9}},144}, 4824 {{{83,7}},59}, {{{0,8}},120}, {{{0,8}},56}, {{{0,9}},208}, 4825 {{{81,7}},17}, {{{0,8}},104}, {{{0,8}},40}, {{{0,9}},176}, 4826 {{{0,8}},8}, {{{0,8}},136}, {{{0,8}},72}, {{{0,9}},240}, 4827 {{{80,7}},4}, {{{0,8}},84}, {{{0,8}},20}, {{{85,8}},227}, 4828 {{{83,7}},43}, {{{0,8}},116}, {{{0,8}},52}, {{{0,9}},200}, 4829 {{{81,7}},13}, {{{0,8}},100}, {{{0,8}},36}, {{{0,9}},168}, 4830 {{{0,8}},4}, {{{0,8}},132}, {{{0,8}},68}, {{{0,9}},232}, 4831 {{{80,7}},8}, {{{0,8}},92}, {{{0,8}},28}, {{{0,9}},152}, 4832 {{{84,7}},83}, {{{0,8}},124}, {{{0,8}},60}, {{{0,9}},216}, 4833 {{{82,7}},23}, {{{0,8}},108}, {{{0,8}},44}, {{{0,9}},184}, 4834 {{{0,8}},12}, {{{0,8}},140}, {{{0,8}},76}, {{{0,9}},248}, 4835 {{{80,7}},3}, {{{0,8}},82}, {{{0,8}},18}, {{{85,8}},163}, 4836 {{{83,7}},35}, {{{0,8}},114}, {{{0,8}},50}, {{{0,9}},196}, 4837 {{{81,7}},11}, {{{0,8}},98}, {{{0,8}},34}, {{{0,9}},164}, 4838 {{{0,8}},2}, {{{0,8}},130}, {{{0,8}},66}, {{{0,9}},228}, 4839 {{{80,7}},7}, {{{0,8}},90}, {{{0,8}},26}, {{{0,9}},148}, 4840 {{{84,7}},67}, {{{0,8}},122}, {{{0,8}},58}, {{{0,9}},212}, 4841 {{{82,7}},19}, {{{0,8}},106}, {{{0,8}},42}, {{{0,9}},180}, 4842 {{{0,8}},10}, {{{0,8}},138}, {{{0,8}},74}, {{{0,9}},244}, 4843 {{{80,7}},5}, {{{0,8}},86}, {{{0,8}},22}, {{{192,8}},0}, 4844 {{{83,7}},51}, {{{0,8}},118}, {{{0,8}},54}, {{{0,9}},204}, 4845 {{{81,7}},15}, {{{0,8}},102}, {{{0,8}},38}, {{{0,9}},172}, 4846 {{{0,8}},6}, {{{0,8}},134}, {{{0,8}},70}, {{{0,9}},236}, 4847 {{{80,7}},9}, {{{0,8}},94}, {{{0,8}},30}, {{{0,9}},156}, 4848 {{{84,7}},99}, {{{0,8}},126}, {{{0,8}},62}, {{{0,9}},220}, 4849 {{{82,7}},27}, {{{0,8}},110}, {{{0,8}},46}, {{{0,9}},188}, 4850 {{{0,8}},14}, {{{0,8}},142}, {{{0,8}},78}, {{{0,9}},252}, 4851 {{{96,7}},256}, {{{0,8}},81}, {{{0,8}},17}, {{{85,8}},131}, 4852 {{{82,7}},31}, {{{0,8}},113}, {{{0,8}},49}, {{{0,9}},194}, 4853 {{{80,7}},10}, {{{0,8}},97}, {{{0,8}},33}, {{{0,9}},162}, 4854 {{{0,8}},1}, {{{0,8}},129}, {{{0,8}},65}, {{{0,9}},226}, 4855 {{{80,7}},6}, {{{0,8}},89}, {{{0,8}},25}, {{{0,9}},146}, 4856 {{{83,7}},59}, {{{0,8}},121}, {{{0,8}},57}, {{{0,9}},210}, 4857 {{{81,7}},17}, {{{0,8}},105}, {{{0,8}},41}, {{{0,9}},178}, 4858 {{{0,8}},9}, {{{0,8}},137}, {{{0,8}},73}, {{{0,9}},242}, 4859 {{{80,7}},4}, {{{0,8}},85}, {{{0,8}},21}, {{{80,8}},258}, 4860 {{{83,7}},43}, {{{0,8}},117}, {{{0,8}},53}, {{{0,9}},202}, 4861 {{{81,7}},13}, {{{0,8}},101}, {{{0,8}},37}, {{{0,9}},170}, 4862 {{{0,8}},5}, {{{0,8}},133}, {{{0,8}},69}, {{{0,9}},234}, 4863 {{{80,7}},8}, {{{0,8}},93}, {{{0,8}},29}, {{{0,9}},154}, 4864 {{{84,7}},83}, {{{0,8}},125}, {{{0,8}},61}, {{{0,9}},218}, 4865 {{{82,7}},23}, {{{0,8}},109}, {{{0,8}},45}, {{{0,9}},186}, 4866 {{{0,8}},13}, {{{0,8}},141}, {{{0,8}},77}, {{{0,9}},250}, 4867 {{{80,7}},3}, {{{0,8}},83}, {{{0,8}},19}, {{{85,8}},195}, 4868 {{{83,7}},35}, {{{0,8}},115}, {{{0,8}},51}, {{{0,9}},198}, 4869 {{{81,7}},11}, {{{0,8}},99}, {{{0,8}},35}, {{{0,9}},166}, 4870 {{{0,8}},3}, {{{0,8}},131}, {{{0,8}},67}, {{{0,9}},230}, 4871 {{{80,7}},7}, {{{0,8}},91}, {{{0,8}},27}, {{{0,9}},150}, 4872 {{{84,7}},67}, {{{0,8}},123}, {{{0,8}},59}, {{{0,9}},214}, 4873 {{{82,7}},19}, {{{0,8}},107}, {{{0,8}},43}, {{{0,9}},182}, 4874 {{{0,8}},11}, {{{0,8}},139}, {{{0,8}},75}, {{{0,9}},246}, 4875 {{{80,7}},5}, {{{0,8}},87}, {{{0,8}},23}, {{{192,8}},0}, 4876 {{{83,7}},51}, {{{0,8}},119}, {{{0,8}},55}, {{{0,9}},206}, 4877 {{{81,7}},15}, {{{0,8}},103}, {{{0,8}},39}, {{{0,9}},174}, 4878 {{{0,8}},7}, {{{0,8}},135}, {{{0,8}},71}, {{{0,9}},238}, 4879 {{{80,7}},9}, {{{0,8}},95}, {{{0,8}},31}, {{{0,9}},158}, 4880 {{{84,7}},99}, {{{0,8}},127}, {{{0,8}},63}, {{{0,9}},222}, 4881 {{{82,7}},27}, {{{0,8}},111}, {{{0,8}},47}, {{{0,9}},190}, 4882 {{{0,8}},15}, {{{0,8}},143}, {{{0,8}},79}, {{{0,9}},254}, 4883 {{{96,7}},256}, {{{0,8}},80}, {{{0,8}},16}, {{{84,8}},115}, 4884 {{{82,7}},31}, {{{0,8}},112}, {{{0,8}},48}, {{{0,9}},193}, 4885 {{{80,7}},10}, {{{0,8}},96}, {{{0,8}},32}, {{{0,9}},161}, 4886 {{{0,8}},0}, {{{0,8}},128}, {{{0,8}},64}, {{{0,9}},225}, 4887 {{{80,7}},6}, {{{0,8}},88}, {{{0,8}},24}, {{{0,9}},145}, 4888 {{{83,7}},59}, {{{0,8}},120}, {{{0,8}},56}, {{{0,9}},209}, 4889 {{{81,7}},17}, {{{0,8}},104}, {{{0,8}},40}, {{{0,9}},177}, 4890 {{{0,8}},8}, {{{0,8}},136}, {{{0,8}},72}, {{{0,9}},241}, 4891 {{{80,7}},4}, {{{0,8}},84}, {{{0,8}},20}, {{{85,8}},227}, 4892 {{{83,7}},43}, {{{0,8}},116}, {{{0,8}},52}, {{{0,9}},201}, 4893 {{{81,7}},13}, {{{0,8}},100}, {{{0,8}},36}, {{{0,9}},169}, 4894 {{{0,8}},4}, {{{0,8}},132}, {{{0,8}},68}, {{{0,9}},233}, 4895 {{{80,7}},8}, {{{0,8}},92}, {{{0,8}},28}, {{{0,9}},153}, 4896 {{{84,7}},83}, {{{0,8}},124}, {{{0,8}},60}, {{{0,9}},217}, 4897 {{{82,7}},23}, {{{0,8}},108}, {{{0,8}},44}, {{{0,9}},185}, 4898 {{{0,8}},12}, {{{0,8}},140}, {{{0,8}},76}, {{{0,9}},249}, 4899 {{{80,7}},3}, {{{0,8}},82}, {{{0,8}},18}, {{{85,8}},163}, 4900 {{{83,7}},35}, {{{0,8}},114}, {{{0,8}},50}, {{{0,9}},197}, 4901 {{{81,7}},11}, {{{0,8}},98}, {{{0,8}},34}, {{{0,9}},165}, 4902 {{{0,8}},2}, {{{0,8}},130}, {{{0,8}},66}, {{{0,9}},229}, 4903 {{{80,7}},7}, {{{0,8}},90}, {{{0,8}},26}, {{{0,9}},149}, 4904 {{{84,7}},67}, {{{0,8}},122}, {{{0,8}},58}, {{{0,9}},213}, 4905 {{{82,7}},19}, {{{0,8}},106}, {{{0,8}},42}, {{{0,9}},181}, 4906 {{{0,8}},10}, {{{0,8}},138}, {{{0,8}},74}, {{{0,9}},245}, 4907 {{{80,7}},5}, {{{0,8}},86}, {{{0,8}},22}, {{{192,8}},0}, 4908 {{{83,7}},51}, {{{0,8}},118}, {{{0,8}},54}, {{{0,9}},205}, 4909 {{{81,7}},15}, {{{0,8}},102}, {{{0,8}},38}, {{{0,9}},173}, 4910 {{{0,8}},6}, {{{0,8}},134}, {{{0,8}},70}, {{{0,9}},237}, 4911 {{{80,7}},9}, {{{0,8}},94}, {{{0,8}},30}, {{{0,9}},157}, 4912 {{{84,7}},99}, {{{0,8}},126}, {{{0,8}},62}, {{{0,9}},221}, 4913 {{{82,7}},27}, {{{0,8}},110}, {{{0,8}},46}, {{{0,9}},189}, 4914 {{{0,8}},14}, {{{0,8}},142}, {{{0,8}},78}, {{{0,9}},253}, 4915 {{{96,7}},256}, {{{0,8}},81}, {{{0,8}},17}, {{{85,8}},131}, 4916 {{{82,7}},31}, {{{0,8}},113}, {{{0,8}},49}, {{{0,9}},195}, 4917 {{{80,7}},10}, {{{0,8}},97}, {{{0,8}},33}, {{{0,9}},163}, 4918 {{{0,8}},1}, {{{0,8}},129}, {{{0,8}},65}, {{{0,9}},227}, 4919 {{{80,7}},6}, {{{0,8}},89}, {{{0,8}},25}, {{{0,9}},147}, 4920 {{{83,7}},59}, {{{0,8}},121}, {{{0,8}},57}, {{{0,9}},211}, 4921 {{{81,7}},17}, {{{0,8}},105}, {{{0,8}},41}, {{{0,9}},179}, 4922 {{{0,8}},9}, {{{0,8}},137}, {{{0,8}},73}, {{{0,9}},243}, 4923 {{{80,7}},4}, {{{0,8}},85}, {{{0,8}},21}, {{{80,8}},258}, 4924 {{{83,7}},43}, {{{0,8}},117}, {{{0,8}},53}, {{{0,9}},203}, 4925 {{{81,7}},13}, {{{0,8}},101}, {{{0,8}},37}, {{{0,9}},171}, 4926 {{{0,8}},5}, {{{0,8}},133}, {{{0,8}},69}, {{{0,9}},235}, 4927 {{{80,7}},8}, {{{0,8}},93}, {{{0,8}},29}, {{{0,9}},155}, 4928 {{{84,7}},83}, {{{0,8}},125}, {{{0,8}},61}, {{{0,9}},219}, 4929 {{{82,7}},23}, {{{0,8}},109}, {{{0,8}},45}, {{{0,9}},187}, 4930 {{{0,8}},13}, {{{0,8}},141}, {{{0,8}},77}, {{{0,9}},251}, 4931 {{{80,7}},3}, {{{0,8}},83}, {{{0,8}},19}, {{{85,8}},195}, 4932 {{{83,7}},35}, {{{0,8}},115}, {{{0,8}},51}, {{{0,9}},199}, 4933 {{{81,7}},11}, {{{0,8}},99}, {{{0,8}},35}, {{{0,9}},167}, 4934 {{{0,8}},3}, {{{0,8}},131}, {{{0,8}},67}, {{{0,9}},231}, 4935 {{{80,7}},7}, {{{0,8}},91}, {{{0,8}},27}, {{{0,9}},151}, 4936 {{{84,7}},67}, {{{0,8}},123}, {{{0,8}},59}, {{{0,9}},215}, 4937 {{{82,7}},19}, {{{0,8}},107}, {{{0,8}},43}, {{{0,9}},183}, 4938 {{{0,8}},11}, {{{0,8}},139}, {{{0,8}},75}, {{{0,9}},247}, 4939 {{{80,7}},5}, {{{0,8}},87}, {{{0,8}},23}, {{{192,8}},0}, 4940 {{{83,7}},51}, {{{0,8}},119}, {{{0,8}},55}, {{{0,9}},207}, 4941 {{{81,7}},15}, {{{0,8}},103}, {{{0,8}},39}, {{{0,9}},175}, 4942 {{{0,8}},7}, {{{0,8}},135}, {{{0,8}},71}, {{{0,9}},239}, 4943 {{{80,7}},9}, {{{0,8}},95}, {{{0,8}},31}, {{{0,9}},159}, 4944 {{{84,7}},99}, {{{0,8}},127}, {{{0,8}},63}, {{{0,9}},223}, 4945 {{{82,7}},27}, {{{0,8}},111}, {{{0,8}},47}, {{{0,9}},191}, 4946 {{{0,8}},15}, {{{0,8}},143}, {{{0,8}},79}, {{{0,9}},255} 4947 }; 4948 local inflate_huft fixed_td[] = { 4949 {{{80,5}},1}, {{{87,5}},257}, {{{83,5}},17}, {{{91,5}},4097}, 4950 {{{81,5}},5}, {{{89,5}},1025}, {{{85,5}},65}, {{{93,5}},16385}, 4951 {{{80,5}},3}, {{{88,5}},513}, {{{84,5}},33}, {{{92,5}},8193}, 4952 {{{82,5}},9}, {{{90,5}},2049}, {{{86,5}},129}, {{{192,5}},24577}, 4953 {{{80,5}},2}, {{{87,5}},385}, {{{83,5}},25}, {{{91,5}},6145}, 4954 {{{81,5}},7}, {{{89,5}},1537}, {{{85,5}},97}, {{{93,5}},24577}, 4955 {{{80,5}},4}, {{{88,5}},769}, {{{84,5}},49}, {{{92,5}},12289}, 4956 {{{82,5}},13}, {{{90,5}},3073}, {{{86,5}},193}, {{{192,5}},24577} 4957 }; 4958 /* --- inffixed.h */ 4959 4960 #endif 4961 4962 4963 int inflate_trees_fixed( 4964 uIntf *bl, /* literal desired/actual bit depth */ 4965 uIntf *bd, /* distance desired/actual bit depth */ 4966 inflate_huft * FAR *tl, /* literal/length tree result */ 4967 inflate_huft * FAR *td, /* distance tree result */ 4968 z_streamp z) /* for memory allocation */ 4969 { 4970 #ifdef BUILDFIXED 4971 /* build fixed tables if not already */ 4972 if (!fixed_built) 4973 { 4974 int k; /* temporary variable */ 4975 uInt f = 0; /* number of hufts used in fixed_mem */ 4976 uIntf *c; /* length list for huft_build */ 4977 uIntf *v; /* work area for huft_build */ 4978 4979 /* allocate memory */ 4980 if ((c = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL) 4981 return Z_MEM_ERROR; 4982 if ((v = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL) 4983 { 4984 ZFREE(z, c); 4985 return Z_MEM_ERROR; 4986 } 4987 4988 /* literal table */ 4989 for (k = 0; k < 144; k++) 4990 c[k] = 8; 4991 for (; k < 256; k++) 4992 c[k] = 9; 4993 for (; k < 280; k++) 4994 c[k] = 7; 4995 for (; k < 288; k++) 4996 c[k] = 8; 4997 fixed_bl = 9; 4998 huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl, 4999 fixed_mem, &f, v); 5000 5001 /* distance table */ 5002 for (k = 0; k < 30; k++) 5003 c[k] = 5; 5004 fixed_bd = 5; 5005 huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd, 5006 fixed_mem, &f, v); 5007 5008 /* done */ 5009 ZFREE(z, v); 5010 ZFREE(z, c); 5011 fixed_built = 1; 5012 } 5013 #endif 5014 *bl = fixed_bl; 5015 *bd = fixed_bd; 5016 *tl = fixed_tl; 5017 *td = fixed_td; 5018 return Z_OK; 5019 } 5020 /* --- inftrees.c */ 5021 5022 /* +++ infcodes.c */ 5023 5024 /* infcodes.c -- process literals and length/distance pairs 5025 * Copyright (C) 1995-2002 Mark Adler 5026 * For conditions of distribution and use, see copyright notice in zlib.h 5027 */ 5028 5029 /* #include "zutil.h" */ 5030 /* #include "inftrees.h" */ 5031 /* #include "infblock.h" */ 5032 /* #include "infcodes.h" */ 5033 /* #include "infutil.h" */ 5034 5035 /* +++ inffast.h */ 5036 5037 /* inffast.h -- header to use inffast.c 5038 * Copyright (C) 1995-2002 Mark Adler 5039 * For conditions of distribution and use, see copyright notice in zlib.h 5040 */ 5041 5042 /* WARNING: this file should *not* be used by applications. It is 5043 part of the implementation of the compression library and is 5044 subject to change. Applications should only use zlib.h. 5045 */ 5046 5047 extern int inflate_fast( 5048 uInt, 5049 uInt, 5050 inflate_huft *, 5051 inflate_huft *, 5052 inflate_blocks_statef *, 5053 z_streamp ); 5054 /* --- inffast.h */ 5055 5056 /* simplify the use of the inflate_huft type with some defines */ 5057 #define exop word.what.Exop 5058 #define bits word.what.Bits 5059 5060 typedef enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */ 5061 START, /* x: set up for LEN */ 5062 LEN, /* i: get length/literal/eob next */ 5063 LENEXT, /* i: getting length extra (have base) */ 5064 DIST, /* i: get distance next */ 5065 DISTEXT, /* i: getting distance extra */ 5066 COPY, /* o: copying bytes in window, waiting for space */ 5067 LIT, /* o: got literal, waiting for output space */ 5068 WASH, /* o: got eob, possibly still output waiting */ 5069 END, /* x: got eob and all data flushed */ 5070 BADCODE} /* x: got error */ 5071 inflate_codes_mode; 5072 5073 /* inflate codes private state */ 5074 struct inflate_codes_state { 5075 5076 /* mode */ 5077 inflate_codes_mode mode; /* current inflate_codes mode */ 5078 5079 /* mode dependent information */ 5080 uInt len; 5081 union { 5082 struct { 5083 inflate_huft *tree; /* pointer into tree */ 5084 uInt need; /* bits needed */ 5085 } code; /* if LEN or DIST, where in tree */ 5086 uInt lit; /* if LIT, literal */ 5087 struct { 5088 uInt get; /* bits to get for extra */ 5089 uInt dist; /* distance back to copy from */ 5090 } copy; /* if EXT or COPY, where and how much */ 5091 } sub; /* submode */ 5092 5093 /* mode independent information */ 5094 Byte lbits; /* ltree bits decoded per branch */ 5095 Byte dbits; /* dtree bits decoder per branch */ 5096 inflate_huft *ltree; /* literal/length/eob tree */ 5097 inflate_huft *dtree; /* distance tree */ 5098 5099 }; 5100 5101 5102 inflate_codes_statef *inflate_codes_new(uInt bl, uInt bd, 5103 inflate_huft *tl, inflate_huft *td, z_streamp z) 5104 { 5105 inflate_codes_statef *c; 5106 5107 if ((c = (inflate_codes_statef *) 5108 ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL) 5109 { 5110 c->mode = START; 5111 c->lbits = (Byte)bl; 5112 c->dbits = (Byte)bd; 5113 c->ltree = tl; 5114 c->dtree = td; 5115 Tracev((stderr, "inflate: codes new\n")); 5116 } 5117 return c; 5118 } 5119 5120 5121 int inflate_codes(inflate_blocks_statef *s, z_streamp z, int r) 5122 { 5123 uInt j; /* temporary storage */ 5124 inflate_huft *t; /* temporary pointer */ 5125 uInt e; /* extra bits or operation */ 5126 uLong b; /* bit buffer */ 5127 uInt k; /* bits in bit buffer */ 5128 Bytef *p; /* input data pointer */ 5129 uInt n; /* bytes available there */ 5130 Bytef *q; /* output window write pointer */ 5131 uInt m; /* bytes to end of window or read pointer */ 5132 Bytef *f; /* pointer to copy strings from */ 5133 inflate_codes_statef *c = s->sub.decode.codes; /* codes state */ 5134 5135 /* copy input/output information to locals (UPDATE macro restores) */ 5136 LOAD 5137 5138 /* process input and output based on current state */ 5139 while (1) switch (c->mode) 5140 { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */ 5141 case START: /* x: set up for LEN */ 5142 #ifndef SLOW 5143 if (m >= 258 && n >= 10) 5144 { 5145 UPDATE 5146 r = inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z); 5147 LOAD 5148 if (r != Z_OK) 5149 { 5150 c->mode = r == Z_STREAM_END ? WASH : BADCODE; 5151 break; 5152 } 5153 } 5154 #endif /* !SLOW */ 5155 c->sub.code.need = c->lbits; 5156 c->sub.code.tree = c->ltree; 5157 c->mode = LEN; 5158 case LEN: /* i: get length/literal/eob next */ 5159 j = c->sub.code.need; 5160 NEEDBITS(j) 5161 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]); 5162 DUMPBITS(t->bits) 5163 e = (uInt)(t->exop); 5164 if (e == 0) /* literal */ 5165 { 5166 c->sub.lit = t->base; 5167 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ? 5168 "inflate: literal '%c'\n" : 5169 "inflate: literal 0x%02x\n", t->base)); 5170 c->mode = LIT; 5171 break; 5172 } 5173 if (e & 16) /* length */ 5174 { 5175 c->sub.copy.get = e & 15; 5176 c->len = t->base; 5177 c->mode = LENEXT; 5178 break; 5179 } 5180 if ((e & 64) == 0) /* next table */ 5181 { 5182 c->sub.code.need = e; 5183 c->sub.code.tree = t + t->base; 5184 break; 5185 } 5186 if (e & 32) /* end of block */ 5187 { 5188 Tracevv((stderr, "inflate: end of block\n")); 5189 c->mode = WASH; 5190 break; 5191 } 5192 c->mode = BADCODE; /* invalid code */ 5193 z->msg = "invalid literal/length code"; 5194 r = Z_DATA_ERROR; 5195 LEAVE 5196 case LENEXT: /* i: getting length extra (have base) */ 5197 j = c->sub.copy.get; 5198 NEEDBITS(j) 5199 c->len += (uInt)b & inflate_mask[j]; 5200 DUMPBITS(j) 5201 c->sub.code.need = c->dbits; 5202 c->sub.code.tree = c->dtree; 5203 Tracevv((stderr, "inflate: length %u\n", c->len)); 5204 c->mode = DIST; 5205 case DIST: /* i: get distance next */ 5206 j = c->sub.code.need; 5207 NEEDBITS(j) 5208 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]); 5209 DUMPBITS(t->bits) 5210 e = (uInt)(t->exop); 5211 if (e & 16) /* distance */ 5212 { 5213 c->sub.copy.get = e & 15; 5214 c->sub.copy.dist = t->base; 5215 c->mode = DISTEXT; 5216 break; 5217 } 5218 if ((e & 64) == 0) /* next table */ 5219 { 5220 c->sub.code.need = e; 5221 c->sub.code.tree = t + t->base; 5222 break; 5223 } 5224 c->mode = BADCODE; /* invalid code */ 5225 z->msg = "invalid distance code"; 5226 r = Z_DATA_ERROR; 5227 LEAVE 5228 case DISTEXT: /* i: getting distance extra */ 5229 j = c->sub.copy.get; 5230 NEEDBITS(j) 5231 c->sub.copy.dist += (uInt)b & inflate_mask[j]; 5232 DUMPBITS(j) 5233 Tracevv((stderr, "inflate: distance %u\n", c->sub.copy.dist)); 5234 c->mode = COPY; 5235 case COPY: /* o: copying bytes in window, waiting for space */ 5236 f = q - c->sub.copy.dist; 5237 while (f < s->window) /* modulo window size-"while" instead */ 5238 f += s->end - s->window; /* of "if" handles invalid distances */ 5239 while (c->len) 5240 { 5241 NEEDOUT 5242 OUTBYTE(*f++) 5243 if (f == s->end) 5244 f = s->window; 5245 c->len--; 5246 } 5247 c->mode = START; 5248 break; 5249 case LIT: /* o: got literal, waiting for output space */ 5250 NEEDOUT 5251 OUTBYTE(c->sub.lit) 5252 c->mode = START; 5253 break; 5254 case WASH: /* o: got eob, possibly more output */ 5255 if (k > 7) /* return unused byte, if any */ 5256 { 5257 Assert(k < 16, "inflate_codes grabbed too many bytes") 5258 k -= 8; 5259 n++; 5260 p--; /* can always return one */ 5261 } 5262 FLUSH 5263 if (s->read != s->write) 5264 LEAVE 5265 c->mode = END; 5266 case END: 5267 r = Z_STREAM_END; 5268 LEAVE 5269 case BADCODE: /* x: got error */ 5270 r = Z_DATA_ERROR; 5271 LEAVE 5272 default: 5273 r = Z_STREAM_ERROR; 5274 LEAVE 5275 } 5276 #ifdef NEED_DUMMY_RETURN 5277 return Z_STREAM_ERROR; /* Some dumb compilers complain without this */ 5278 #endif 5279 } 5280 5281 5282 void inflate_codes_free(inflate_codes_statef *c, z_streamp z) 5283 { 5284 ZFREE(z, c); 5285 Tracev((stderr, "inflate: codes free\n")); 5286 } 5287 /* --- infcodes.c */ 5288 5289 /* +++ infutil.c */ 5290 5291 /* inflate_util.c -- data and routines common to blocks and codes 5292 * Copyright (C) 1995-2002 Mark Adler 5293 * For conditions of distribution and use, see copyright notice in zlib.h 5294 */ 5295 5296 /* #include "zutil.h" */ 5297 /* #include "infblock.h" */ 5298 /* #include "inftrees.h" */ 5299 /* #include "infcodes.h" */ 5300 /* #include "infutil.h" */ 5301 5302 #ifndef NO_DUMMY_DECL 5303 struct inflate_codes_state {int dummy;}; /* for buggy compilers */ 5304 #endif 5305 5306 /* And'ing with mask[n] masks the lower n bits */ 5307 uInt inflate_mask[17] = { 5308 0x0000, 5309 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff, 5310 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff 5311 }; 5312 5313 5314 /* copy as much as possible from the sliding window to the output area */ 5315 int inflate_flush(inflate_blocks_statef *s, z_streamp z, int r) 5316 { 5317 uInt n; 5318 Bytef *p; 5319 Bytef *q; 5320 5321 /* local copies of source and destination pointers */ 5322 p = z->next_out; 5323 q = s->read; 5324 5325 /* compute number of bytes to copy as far as end of window */ 5326 n = (uInt)((q <= s->write ? s->write : s->end) - q); 5327 if (n > z->avail_out) n = z->avail_out; 5328 if (n && r == Z_BUF_ERROR) r = Z_OK; 5329 5330 /* update counters */ 5331 z->avail_out -= n; 5332 z->total_out += n; 5333 5334 /* update check information */ 5335 if (s->checkfn != Z_NULL) 5336 z->adler = s->check = (*s->checkfn)(s->check, q, n); 5337 5338 /* copy as far as end of window */ 5339 if (p != Z_NULL) { 5340 zmemcpy(p, q, n); 5341 p += n; 5342 } 5343 q += n; 5344 5345 /* see if more to copy at beginning of window */ 5346 if (q == s->end) 5347 { 5348 /* wrap pointers */ 5349 q = s->window; 5350 if (s->write == s->end) 5351 s->write = s->window; 5352 5353 /* compute bytes to copy */ 5354 n = (uInt)(s->write - q); 5355 if (n > z->avail_out) n = z->avail_out; 5356 if (n && r == Z_BUF_ERROR) r = Z_OK; 5357 5358 /* update counters */ 5359 z->avail_out -= n; 5360 z->total_out += n; 5361 5362 /* update check information */ 5363 if (s->checkfn != Z_NULL) 5364 z->adler = s->check = (*s->checkfn)(s->check, q, n); 5365 5366 /* copy */ 5367 if (p != NULL) { 5368 zmemcpy(p, q, n); 5369 p += n; 5370 } 5371 q += n; 5372 } 5373 5374 /* update pointers */ 5375 z->next_out = p; 5376 s->read = q; 5377 5378 /* done */ 5379 return r; 5380 } 5381 /* --- infutil.c */ 5382 5383 /* +++ inffast.c */ 5384 5385 /* inffast.c -- process literals and length/distance pairs fast 5386 * Copyright (C) 1995-2002 Mark Adler 5387 * For conditions of distribution and use, see copyright notice in zlib.h 5388 */ 5389 5390 /* #include "zutil.h" */ 5391 /* #include "inftrees.h" */ 5392 /* #include "infblock.h" */ 5393 /* #include "infcodes.h" */ 5394 /* #include "infutil.h" */ 5395 /* #include "inffast.h" */ 5396 5397 #ifndef NO_DUMMY_DECL 5398 struct inflate_codes_state {int dummy;}; /* for buggy compilers */ 5399 #endif 5400 5401 /* simplify the use of the inflate_huft type with some defines */ 5402 #define exop word.what.Exop 5403 #define bits word.what.Bits 5404 5405 /* macros for bit input with no checking and for returning unused bytes */ 5406 #define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}} 5407 #define UNGRAB {c=z->avail_in-n;c=(k>>3)<c?k>>3:c;n+=c;p-=c;k-=c<<3;} 5408 5409 /* Called with number of bytes left to write in window at least 258 5410 (the maximum string length) and number of input bytes available 5411 at least ten. The ten bytes are six bytes for the longest length/ 5412 distance pair plus four bytes for overloading the bit buffer. */ 5413 5414 int inflate_fast(uInt bl, uInt bd, 5415 inflate_huft *tl, 5416 inflate_huft *td, 5417 inflate_blocks_statef *s, 5418 z_streamp z) 5419 { 5420 inflate_huft *t; /* temporary pointer */ 5421 uInt e; /* extra bits or operation */ 5422 uLong b; /* bit buffer */ 5423 uInt k; /* bits in bit buffer */ 5424 Bytef *p; /* input data pointer */ 5425 uInt n; /* bytes available there */ 5426 Bytef *q; /* output window write pointer */ 5427 uInt m; /* bytes to end of window or read pointer */ 5428 uInt ml; /* mask for literal/length tree */ 5429 uInt md; /* mask for distance tree */ 5430 uInt c; /* bytes to copy */ 5431 uInt d; /* distance back to copy from */ 5432 Bytef *r; /* copy source pointer */ 5433 5434 /* load input, output, bit values */ 5435 LOAD 5436 5437 /* initialize masks */ 5438 ml = inflate_mask[bl]; 5439 md = inflate_mask[bd]; 5440 5441 /* do until not enough input or output space for fast loop */ 5442 do { /* assume called with m >= 258 && n >= 10 */ 5443 /* get literal/length code */ 5444 GRABBITS(20) /* max bits for literal/length code */ 5445 if ((e = (t = tl + ((uInt)b & ml))->exop) == 0) 5446 { 5447 DUMPBITS(t->bits) 5448 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ? 5449 "inflate: * literal '%c'\n" : 5450 "inflate: * literal 0x%02x\n", t->base)); 5451 *q++ = (Byte)t->base; 5452 m--; 5453 continue; 5454 } 5455 do { 5456 DUMPBITS(t->bits) 5457 if (e & 16) 5458 { 5459 /* get extra bits for length */ 5460 e &= 15; 5461 c = t->base + ((uInt)b & inflate_mask[e]); 5462 DUMPBITS(e) 5463 Tracevv((stderr, "inflate: * length %u\n", c)); 5464 5465 /* decode distance base of block to copy */ 5466 GRABBITS(15); /* max bits for distance code */ 5467 e = (t = td + ((uInt)b & md))->exop; 5468 do { 5469 DUMPBITS(t->bits) 5470 if (e & 16) 5471 { 5472 /* get extra bits to add to distance base */ 5473 e &= 15; 5474 GRABBITS(e) /* get extra bits (up to 13) */ 5475 d = t->base + ((uInt)b & inflate_mask[e]); 5476 DUMPBITS(e) 5477 Tracevv((stderr, "inflate: * distance %u\n", d)); 5478 5479 /* do the copy */ 5480 m -= c; 5481 r = q - d; 5482 if (r < s->window) /* wrap if needed */ 5483 { 5484 do { 5485 r += s->end - s->window; /* force pointer in window */ 5486 } while (r < s->window); /* covers invalid distances */ 5487 e = s->end - r; 5488 if (c > e) 5489 { 5490 c -= e; /* wrapped copy */ 5491 do { 5492 *q++ = *r++; 5493 } while (--e); 5494 r = s->window; 5495 do { 5496 *q++ = *r++; 5497 } while (--c); 5498 } 5499 else /* normal copy */ 5500 { 5501 *q++ = *r++; c--; 5502 *q++ = *r++; c--; 5503 do { 5504 *q++ = *r++; 5505 } while (--c); 5506 } 5507 } 5508 else /* normal copy */ 5509 { 5510 *q++ = *r++; c--; 5511 *q++ = *r++; c--; 5512 do { 5513 *q++ = *r++; 5514 } while (--c); 5515 } 5516 break; 5517 } 5518 else if ((e & 64) == 0) 5519 { 5520 t += t->base; 5521 e = (t += ((uInt)b & inflate_mask[e]))->exop; 5522 } 5523 else 5524 { 5525 z->msg = "invalid distance code"; 5526 UNGRAB 5527 UPDATE 5528 return Z_DATA_ERROR; 5529 } 5530 } while (1); 5531 break; 5532 } 5533 if ((e & 64) == 0) 5534 { 5535 t += t->base; 5536 if ((e = (t += ((uInt)b & inflate_mask[e]))->exop) == 0) 5537 { 5538 DUMPBITS(t->bits) 5539 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ? 5540 "inflate: * literal '%c'\n" : 5541 "inflate: * literal 0x%02x\n", t->base)); 5542 *q++ = (Byte)t->base; 5543 m--; 5544 break; 5545 } 5546 } 5547 else if (e & 32) 5548 { 5549 Tracevv((stderr, "inflate: * end of block\n")); 5550 UNGRAB 5551 UPDATE 5552 return Z_STREAM_END; 5553 } 5554 else 5555 { 5556 z->msg = "invalid literal/length code"; 5557 UNGRAB 5558 UPDATE 5559 return Z_DATA_ERROR; 5560 } 5561 } while (1); 5562 } while (m >= 258 && n >= 10); 5563 5564 /* not enough input or output--restore pointers and return */ 5565 UNGRAB 5566 UPDATE 5567 return Z_OK; 5568 } 5569 /* --- inffast.c */ 5570 5571 /* +++ zutil.c */ 5572 5573 /* zutil.c -- target dependent utility functions for the compression library 5574 * Copyright (C) 1995-2002 Jean-loup Gailly. 5575 * For conditions of distribution and use, see copyright notice in zlib.h 5576 */ 5577 5578 /* @(#) Id */ 5579 5580 #ifdef DEBUG_ZLIB 5581 #include <stdio.h> 5582 #endif 5583 5584 /* #include "zutil.h" */ 5585 5586 #ifndef NO_DUMMY_DECL 5587 struct internal_state {int dummy;}; /* for buggy compilers */ 5588 #endif 5589 5590 #ifndef STDC 5591 extern void exit(int); 5592 #endif 5593 5594 const char *z_errmsg[10] = { 5595 "need dictionary", /* Z_NEED_DICT 2 */ 5596 "stream end", /* Z_STREAM_END 1 */ 5597 "", /* Z_OK 0 */ 5598 "file error", /* Z_ERRNO (-1) */ 5599 "stream error", /* Z_STREAM_ERROR (-2) */ 5600 "data error", /* Z_DATA_ERROR (-3) */ 5601 "insufficient memory", /* Z_MEM_ERROR (-4) */ 5602 "buffer error", /* Z_BUF_ERROR (-5) */ 5603 "incompatible version",/* Z_VERSION_ERROR (-6) */ 5604 ""}; 5605 5606 5607 #if 0 5608 const char * ZEXPORT zlibVersion() 5609 { 5610 return ZLIB_VERSION; 5611 } 5612 #endif 5613 5614 #ifdef DEBUG_ZLIB 5615 5616 # ifndef verbose 5617 # define verbose 0 5618 # endif 5619 int z_verbose = verbose; 5620 5621 void z_error (m) 5622 char *m; 5623 { 5624 fprintf(stderr, "%s\n", m); 5625 exit(1); 5626 } 5627 #endif 5628 5629 /* exported to allow conversion of error code to string for compress() and 5630 * uncompress() 5631 */ 5632 #if 0 5633 const char * ZEXPORT zError(err) 5634 int err; 5635 { 5636 return ERR_MSG(err); 5637 } 5638 #endif 5639 5640 5641 #ifndef HAVE_MEMCPY 5642 5643 void zmemcpy(dest, source, len) 5644 Bytef* dest; 5645 const Bytef* source; 5646 uInt len; 5647 { 5648 if (len == 0) return; 5649 do { 5650 *dest++ = *source++; /* ??? to be unrolled */ 5651 } while (--len != 0); 5652 } 5653 5654 int zmemcmp(s1, s2, len) 5655 const Bytef* s1; 5656 const Bytef* s2; 5657 uInt len; 5658 { 5659 uInt j; 5660 5661 for (j = 0; j < len; j++) { 5662 if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1; 5663 } 5664 return 0; 5665 } 5666 5667 void zmemzero(dest, len) 5668 Bytef* dest; 5669 uInt len; 5670 { 5671 if (len == 0) return; 5672 do { 5673 *dest++ = 0; /* ??? to be unrolled */ 5674 } while (--len != 0); 5675 } 5676 #endif 5677 5678 #ifdef __TURBOC__ 5679 #if (defined( __BORLANDC__) || !defined(SMALL_MEDIUM)) && !defined(__32BIT__) 5680 /* Small and medium model in Turbo C are for now limited to near allocation 5681 * with reduced MAX_WBITS and MAX_MEM_LEVEL 5682 */ 5683 # define MY_ZCALLOC 5684 5685 /* Turbo C malloc() does not allow dynamic allocation of 64K bytes 5686 * and farmalloc(64K) returns a pointer with an offset of 8, so we 5687 * must fix the pointer. Warning: the pointer must be put back to its 5688 * original form in order to free it, use zcfree(). 5689 */ 5690 5691 #define MAX_PTR 10 5692 /* 10*64K = 640K */ 5693 5694 local int next_ptr = 0; 5695 5696 typedef struct ptr_table_s { 5697 voidpf org_ptr; 5698 voidpf new_ptr; 5699 } ptr_table; 5700 5701 local ptr_table table[MAX_PTR]; 5702 /* This table is used to remember the original form of pointers 5703 * to large buffers (64K). Such pointers are normalized with a zero offset. 5704 * Since MSDOS is not a preemptive multitasking OS, this table is not 5705 * protected from concurrent access. This hack doesn't work anyway on 5706 * a protected system like OS/2. Use Microsoft C instead. 5707 */ 5708 5709 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size) 5710 { 5711 voidpf buf = opaque; /* just to make some compilers happy */ 5712 ulg bsize = (ulg)items*size; 5713 5714 /* If we allocate less than 65520 bytes, we assume that farmalloc 5715 * will return a usable pointer which doesn't have to be normalized. 5716 */ 5717 if (bsize < 65520L) { 5718 buf = farmalloc(bsize); 5719 if (*(ush*)&buf != 0) return buf; 5720 } else { 5721 buf = farmalloc(bsize + 16L); 5722 } 5723 if (buf == NULL || next_ptr >= MAX_PTR) return NULL; 5724 table[next_ptr].org_ptr = buf; 5725 5726 /* Normalize the pointer to seg:0 */ 5727 *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4; 5728 *(ush*)&buf = 0; 5729 table[next_ptr++].new_ptr = buf; 5730 return buf; 5731 } 5732 5733 void zcfree (voidpf opaque, voidpf ptr) 5734 { 5735 int n; 5736 if (*(ush*)&ptr != 0) { /* object < 64K */ 5737 farfree(ptr); 5738 return; 5739 } 5740 /* Find the original pointer */ 5741 for (n = 0; n < next_ptr; n++) { 5742 if (ptr != table[n].new_ptr) continue; 5743 5744 farfree(table[n].org_ptr); 5745 while (++n < next_ptr) { 5746 table[n-1] = table[n]; 5747 } 5748 next_ptr--; 5749 return; 5750 } 5751 ptr = opaque; /* just to make some compilers happy */ 5752 Assert(0, "zcfree: ptr not found"); 5753 } 5754 #endif 5755 #endif /* __TURBOC__ */ 5756 5757 5758 #if defined(M_I86) && !defined(__32BIT__) 5759 /* Microsoft C in 16-bit mode */ 5760 5761 # define MY_ZCALLOC 5762 5763 #if (!defined(_MSC_VER) || (_MSC_VER <= 600)) 5764 # define _halloc halloc 5765 # define _hfree hfree 5766 #endif 5767 5768 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size) 5769 { 5770 if (opaque) opaque = 0; /* to make compiler happy */ 5771 return _halloc((long)items, size); 5772 } 5773 5774 void zcfree (voidpf opaque, voidpf ptr) 5775 { 5776 if (opaque) opaque = 0; /* to make compiler happy */ 5777 _hfree(ptr); 5778 } 5779 5780 #endif /* MSC */ 5781 5782 5783 #ifndef MY_ZCALLOC /* Any system without a special alloc function */ 5784 5785 #ifndef STDC 5786 extern voidp calloc(uInt items, uInt size); 5787 extern void free(voidpf ptr); 5788 #endif 5789 5790 voidpf zcalloc (opaque, items, size) 5791 voidpf opaque; 5792 unsigned items; 5793 unsigned size; 5794 { 5795 if (opaque) items += size - size; /* make compiler happy */ 5796 return (voidpf)calloc(items, size); 5797 } 5798 5799 void zcfree (opaque, ptr) 5800 voidpf opaque; 5801 voidpf ptr; 5802 { 5803 free(ptr); 5804 if (opaque) return; /* make compiler happy */ 5805 } 5806 5807 #endif /* MY_ZCALLOC */ 5808 /* --- zutil.c */ 5809 5810 /* +++ adler32.c */ 5811 /* adler32.c -- compute the Adler-32 checksum of a data stream 5812 * Copyright (C) 1995-2002 Mark Adler 5813 * For conditions of distribution and use, see copyright notice in zlib.h 5814 */ 5815 5816 /* @(#) $Id: zlib.c,v 1.33 2009/03/18 10:22:42 cegger Exp $ */ 5817 5818 /* #include "zlib.h" */ 5819 5820 #define BASE 65521L /* largest prime smaller than 65536 */ 5821 #define NMAX 5552 5822 /* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */ 5823 5824 #define DO1(buf,i) {s1 += buf[i]; s2 += s1;} 5825 #define DO2(buf,i) DO1(buf,i); DO1(buf,i+1); 5826 #define DO4(buf,i) DO2(buf,i); DO2(buf,i+2); 5827 #define DO8(buf,i) DO4(buf,i); DO4(buf,i+4); 5828 #define DO16(buf) DO8(buf,0); DO8(buf,8); 5829 5830 /* ========================================================================= */ 5831 uLong ZEXPORT adler32(uLong adler, const Bytef *buf, uInt len) 5832 { 5833 unsigned long s1 = adler & 0xffff; 5834 unsigned long s2 = (adler >> 16) & 0xffff; 5835 int k; 5836 5837 if (buf == Z_NULL) return 1L; 5838 5839 while (len > 0) { 5840 k = len < NMAX ? len : NMAX; 5841 len -= k; 5842 while (k >= 16) { 5843 DO16(buf); 5844 buf += 16; 5845 k -= 16; 5846 } 5847 if (k != 0) do { 5848 s1 += *buf++; 5849 s2 += s1; 5850 } while (--k); 5851 s1 %= BASE; 5852 s2 %= BASE; 5853 } 5854 return (s2 << 16) | s1; 5855 } 5856 /* --- adler32.c */ 5857 5858