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1 /*
2 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
6 * Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
7 *
8 * This file contains Original Code and/or Modifications of Original Code
9 * as defined in and that are subject to the Apple Public Source License
10 * Version 2.0 (the 'License'). You may not use this file except in
11 * compliance with the License. Please obtain a copy of the License at
12 * http://www.opensource.apple.com/apsl/ and read it before using this
13 * file.
14 *
15 * The Original Code and all software distributed under the License are
16 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
17 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
18 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
20 * Please see the License for the specific language governing rights and
21 * limitations under the License.
22 *
23 * @APPLE_LICENSE_HEADER_END@
24 */
25 /*
26 * This file is derived from various .h and .c files from the zlib-1.0.4
27 * distribution by Jean-loup Gailly and Mark Adler, with some additions
28 * by Paul Mackerras to aid in implementing Deflate compression and
29 * decompression for PPP packets. See zlib.h for conditions of
30 * distribution and use.
31 *
32 * Changes that have been made include:
33 * - added Z_PACKET_FLUSH (see zlib.h for details)
34 * - added inflateIncomp and deflateOutputPending
35 * - allow strm->next_out to be NULL, meaning discard the output
36 *
37 * $FreeBSD: src/sys/net/zlib.c,v 1.10 1999/12/29 04:38:38 peter Exp $
38 */
39
40 #define NO_DUMMY_DECL
41 #define NO_ZCFUNCS
42 #define MY_ZCALLOC
43
44 /* +++ zutil.h */
45 /* zutil.h -- internal interface and configuration of the compression library
46 * Copyright (C) 1995-2002 Jean-loup Gailly.
47 * For conditions of distribution and use, see copyright notice in zlib.h
48 */
49
50 /* WARNING: this file should *not* be used by applications. It is
51 part of the implementation of the compression library and is
52 subject to change. Applications should only use zlib.h.
53 */
54
55 /* @(#) $Id: zlib.c,v 1.9 2002/11/28 00:56:55 lindak Exp $ */
56
57 #ifndef _Z_UTIL_H
58 #define _Z_UTIL_H
59
60 #ifdef KERNEL
61 #include <net/zlib.h>
62 #else
63 #include "zlib.h"
64 #endif
65
66 #ifdef KERNEL
67 /* Assume this is a *BSD or SVR4 kernel */
68 #include <sys/types.h>
69 #include <sys/time.h>
70 #include <sys/systm.h>
71 # define HAVE_MEMCPY
72 # define memcpy(d, s, n) bcopy((s), (d), (n))
73 # define memset(d, v, n) bzero((d), (n))
74 # define memcmp bcmp
75
76 #else
77 #if defined(__KERNEL__)
78 /* Assume this is a Linux kernel */
79 #include <linux/string.h>
80 #define HAVE_MEMCPY
81
82 #else /* not kernel */
83 #ifdef STDC
84 # include <stddef.h>
85 # include <string.h>
86 # include <stdlib.h>
87 #endif
88 #ifdef NO_ERRNO_H
89 extern int errno;
90 #else
91 # include <errno.h>
92 #endif
93 #endif /* __KERNEL__ */
94 #endif /* KERNEL */
95
96 #ifndef local
97 # define local static
98 #endif
99 /* compile with -Dlocal if your debugger can't find static symbols */
100
101 typedef unsigned char uch;
102 typedef uch FAR uchf;
103 typedef unsigned short ush;
104 typedef ush FAR ushf;
105 typedef unsigned long ulg;
106
107 extern const char *z_errmsg[10]; /* indexed by 2-zlib_error */
108 /* (size given to avoid silly warnings with Visual C++) */
109
110 #define ERR_MSG(err) z_errmsg[Z_NEED_DICT-(err)]
111
112 #define ERR_RETURN(strm,err) \
113 return (strm->msg = (char*)ERR_MSG(err), (err))
114 /* To be used only when the state is known to be valid */
115
116 /* common constants */
117
118 #ifndef DEF_WBITS
119 # define DEF_WBITS MAX_WBITS
120 #endif
121 /* default windowBits for decompression. MAX_WBITS is for compression only */
122
123 #if MAX_MEM_LEVEL >= 8
124 # define DEF_MEM_LEVEL 8
125 #else
126 # define DEF_MEM_LEVEL MAX_MEM_LEVEL
127 #endif
128 /* default memLevel */
129
130 #define STORED_BLOCK 0
131 #define STATIC_TREES 1
132 #define DYN_TREES 2
133 /* The three kinds of block type */
134
135 #define MIN_MATCH 3
136 #define MAX_MATCH 258
137 /* The minimum and maximum match lengths */
138
139 #define PRESET_DICT 0x20 /* preset dictionary flag in zlib header */
140
141 /* target dependencies */
142
143 #ifdef MSDOS
144 # define OS_CODE 0x00
145 # if defined(__TURBOC__) || defined(__BORLANDC__)
146 # if(__STDC__ == 1) && (defined(__LARGE__) || defined(__COMPACT__))
147 /* Allow compilation with ANSI keywords only enabled */
148 void _Cdecl farfree( void *block );
149 void *_Cdecl farmalloc( unsigned long nbytes );
150 # else
151 # include <alloc.h>
152 # endif
153 # else /* MSC or DJGPP */
154 # include <malloc.h>
155 # endif
156 #endif
157
158 #ifdef OS2
159 # define OS_CODE 0x06
160 #endif
161
162 #ifdef WIN32 /* Window 95 & Windows NT */
163 # define OS_CODE 0x0b
164 #endif
165
166 #if defined(VAXC) || defined(VMS)
167 # define OS_CODE 0x02
168 # define F_OPEN(name, mode) \
169 fopen((name), (mode), "mbc=60", "ctx=stm", "rfm=fix", "mrs=512")
170 #endif
171
172 #ifdef AMIGA
173 # define OS_CODE 0x01
174 #endif
175
176 #if defined(ATARI) || defined(atarist)
177 # define OS_CODE 0x05
178 #endif
179
180 #if defined(MACOS) || defined(TARGET_OS_MAC)
181 # define OS_CODE 0x07
182 # if defined(__MWERKS__) && __dest_os != __be_os && __dest_os != __win32_os
183 # include <unix.h> /* for fdopen */
184 # else
185 # ifndef fdopen
186 # define fdopen(fd,mode) NULL /* No fdopen() */
187 # endif
188 # endif
189 #endif
190
191 #ifdef __50SERIES /* Prime/PRIMOS */
192 # define OS_CODE 0x0F
193 #endif
194
195 #ifdef TOPS20
196 # define OS_CODE 0x0a
197 #endif
198
199 #if defined(_BEOS_) || defined(RISCOS)
200 # define fdopen(fd,mode) NULL /* No fdopen() */
201 #endif
202
203 #if (defined(_MSC_VER) && (_MSC_VER > 600))
204 # define fdopen(fd,type) _fdopen(fd,type)
205 #endif
206
207
208 /* Common defaults */
209
210 #ifndef OS_CODE
211 # define OS_CODE 0x03 /* assume Unix */
212 #endif
213
214 #ifndef F_OPEN
215 # define F_OPEN(name, mode) fopen((name), (mode))
216 #endif
217
218 /* functions */
219
220 #ifdef HAVE_STRERROR
221 extern char *strerror OF((int));
222 # define zstrerror(errnum) strerror(errnum)
223 #else
224 # define zstrerror(errnum) ""
225 #endif
226
227 #if defined(pyr)
228 # define NO_MEMCPY
229 #endif
230 #if defined(SMALL_MEDIUM) && !defined(_MSC_VER) && !defined(__SC__)
231 /* Use our own functions for small and medium model with MSC <= 5.0.
232 * You may have to use the same strategy for Borland C (untested).
233 * The __SC__ check is for Symantec.
234 */
235 # define NO_MEMCPY
236 #endif
237 #if defined(STDC) && !defined(HAVE_MEMCPY) && !defined(NO_MEMCPY)
238 # define HAVE_MEMCPY
239 #endif
240 #ifdef HAVE_MEMCPY
241 # ifdef SMALL_MEDIUM /* MSDOS small or medium model */
242 # define zmemcpy _fmemcpy
243 # define zmemcmp _fmemcmp
244 # define zmemzero(dest, len) _fmemset(dest, 0, len)
245 # else
246 # define zmemcpy memcpy
247 # define zmemcmp memcmp
248 # define zmemzero(dest, len) memset(dest, 0, len)
249 # endif
250 #else
251 extern void zmemcpy OF((Bytef* dest, const Bytef* source, uInt len));
252 extern int zmemcmp OF((const Bytef* s1, const Bytef* s2, uInt len));
253 extern void zmemzero OF((Bytef* dest, uInt len));
254 #endif
255
256 /* Diagnostic functions */
257 #ifdef DEBUG_ZLIB
258 # include <stdio.h>
259 extern int z_verbose;
260 extern void z_error OF((char *m));
261 # define Assert(cond,msg) {if(!(cond)) z_error(msg);}
262 # define Trace(x) {if (z_verbose>=0) fprintf x ;}
263 # define Tracev(x) {if (z_verbose>0) fprintf x ;}
264 # define Tracevv(x) {if (z_verbose>1) fprintf x ;}
265 # define Tracec(c,x) {if (z_verbose>0 && (c)) fprintf x ;}
266 # define Tracecv(c,x) {if (z_verbose>1 && (c)) fprintf x ;}
267 #else
268 # define Assert(cond,msg)
269 # define Trace(x)
270 # define Tracev(x)
271 # define Tracevv(x)
272 # define Tracec(c,x)
273 # define Tracecv(c,x)
274 #endif
275
276
277 typedef uLong (ZEXPORT *check_func) OF((uLong check, const Bytef *buf,
278 uInt len));
279 voidpf zcalloc OF((voidpf opaque, unsigned items, unsigned size));
280 void zcfree OF((voidpf opaque, voidpf ptr));
281
282 #define ZALLOC(strm, items, size) \
283 (*((strm)->zalloc))((strm)->opaque, (items), (size))
284 #define ZFREE(strm, addr) (*((strm)->zfree))((strm)->opaque, (voidpf)(addr))
285 #define TRY_FREE(s, p) {if (p) ZFREE(s, p);}
286
287 #endif /* _Z_UTIL_H */
288 /* --- zutil.h */
289
290 /* +++ deflate.h */
291 /* deflate.h -- internal compression state
292 * Copyright (C) 1995-2002 Jean-loup Gailly
293 * For conditions of distribution and use, see copyright notice in zlib.h
294 */
295
296 /* WARNING: this file should *not* be used by applications. It is
297 part of the implementation of the compression library and is
298 subject to change. Applications should only use zlib.h.
299 */
300
301 /* @(#) $Id: zlib.c,v 1.9 2002/11/28 00:56:55 lindak Exp $ */
302
303 #ifndef _DEFLATE_H
304 #define _DEFLATE_H
305
306 /* #include "zutil.h" */
307
308 /* ===========================================================================
309 * Internal compression state.
310 */
311
312 #define LENGTH_CODES 29
313 /* number of length codes, not counting the special END_BLOCK code */
314
315 #define LITERALS 256
316 /* number of literal bytes 0..255 */
317
318 #define L_CODES (LITERALS+1+LENGTH_CODES)
319 /* number of Literal or Length codes, including the END_BLOCK code */
320
321 #define D_CODES 30
322 /* number of distance codes */
323
324 #define BL_CODES 19
325 /* number of codes used to transfer the bit lengths */
326
327 #define HEAP_SIZE (2*L_CODES+1)
328 /* maximum heap size */
329
330 #define MAX_BITS 15
331 /* All codes must not exceed MAX_BITS bits */
332
333 #define INIT_STATE 42
334 #define BUSY_STATE 113
335 #define FINISH_STATE 666
336 /* Stream status */
337
338
339 /* Data structure describing a single value and its code string. */
340 typedef struct ct_data_s {
341 union {
342 ush freq; /* frequency count */
343 ush code; /* bit string */
344 } fc;
345 union {
346 ush dad; /* father node in Huffman tree */
347 ush len; /* length of bit string */
348 } dl;
349 } FAR ct_data;
350
351 #define Freq fc.freq
352 #define Code fc.code
353 #define Dad dl.dad
354 #define Len dl.len
355
356 typedef struct static_tree_desc_s static_tree_desc;
357
358 typedef struct tree_desc_s {
359 ct_data *dyn_tree; /* the dynamic tree */
360 int max_code; /* largest code with non zero frequency */
361 static_tree_desc *stat_desc; /* the corresponding static tree */
362 } FAR tree_desc;
363
364 typedef ush Pos;
365 typedef Pos FAR Posf;
366 typedef unsigned IPos;
367
368 /* A Pos is an index in the character window. We use short instead of int to
369 * save space in the various tables. IPos is used only for parameter passing.
370 */
371
372 typedef struct deflate_state {
373 z_streamp strm; /* pointer back to this zlib stream */
374 int status; /* as the name implies */
375 Bytef *pending_buf; /* output still pending */
376 ulg pending_buf_size; /* size of pending_buf */
377 Bytef *pending_out; /* next pending byte to output to the stream */
378 int pending; /* nb of bytes in the pending buffer */
379 int noheader; /* suppress zlib header and adler32 */
380 Byte data_type; /* UNKNOWN, BINARY or ASCII */
381 Byte method; /* STORED (for zip only) or DEFLATED */
382 int last_flush; /* value of flush param for previous deflate call */
383
384 /* used by deflate.c: */
385
386 uInt w_size; /* LZ77 window size (32K by default) */
387 uInt w_bits; /* log2(w_size) (8..16) */
388 uInt w_mask; /* w_size - 1 */
389
390 Bytef *window;
391 /* Sliding window. Input bytes are read into the second half of the window,
392 * and move to the first half later to keep a dictionary of at least wSize
393 * bytes. With this organization, matches are limited to a distance of
394 * wSize-MAX_MATCH bytes, but this ensures that IO is always
395 * performed with a length multiple of the block size. Also, it limits
396 * the window size to 64K, which is quite useful on MSDOS.
397 * To do: use the user input buffer as sliding window.
398 */
399
400 ulg window_size;
401 /* Actual size of window: 2*wSize, except when the user input buffer
402 * is directly used as sliding window.
403 */
404
405 Posf *prev;
406 /* Link to older string with same hash index. To limit the size of this
407 * array to 64K, this link is maintained only for the last 32K strings.
408 * An index in this array is thus a window index modulo 32K.
409 */
410
411 Posf *head; /* Heads of the hash chains or NIL. */
412
413 uInt ins_h; /* hash index of string to be inserted */
414 uInt hash_size; /* number of elements in hash table */
415 uInt hash_bits; /* log2(hash_size) */
416 uInt hash_mask; /* hash_size-1 */
417
418 uInt hash_shift;
419 /* Number of bits by which ins_h must be shifted at each input
420 * step. It must be such that after MIN_MATCH steps, the oldest
421 * byte no longer takes part in the hash key, that is:
422 * hash_shift * MIN_MATCH >= hash_bits
423 */
424
425 long block_start;
426 /* Window position at the beginning of the current output block. Gets
427 * negative when the window is moved backwards.
428 */
429
430 uInt match_length; /* length of best match */
431 IPos prev_match; /* previous match */
432 int match_available; /* set if previous match exists */
433 uInt strstart; /* start of string to insert */
434 uInt match_start; /* start of matching string */
435 uInt lookahead; /* number of valid bytes ahead in window */
436
437 uInt prev_length;
438 /* Length of the best match at previous step. Matches not greater than this
439 * are discarded. This is used in the lazy match evaluation.
440 */
441
442 uInt max_chain_length;
443 /* To speed up deflation, hash chains are never searched beyond this
444 * length. A higher limit improves compression ratio but degrades the
445 * speed.
446 */
447
448 uInt max_lazy_match;
449 /* Attempt to find a better match only when the current match is strictly
450 * smaller than this value. This mechanism is used only for compression
451 * levels >= 4.
452 */
453 # define max_insert_length max_lazy_match
454 /* Insert new strings in the hash table only if the match length is not
455 * greater than this length. This saves time but degrades compression.
456 * max_insert_length is used only for compression levels <= 3.
457 */
458
459 int level; /* compression level (1..9) */
460 int strategy; /* favor or force Huffman coding*/
461
462 uInt good_match;
463 /* Use a faster search when the previous match is longer than this */
464
465 int nice_match; /* Stop searching when current match exceeds this */
466
467 /* used by trees.c: */
468 /* Didn't use ct_data typedef below to supress compiler warning */
469 struct ct_data_s dyn_ltree[HEAP_SIZE]; /* literal and length tree */
470 struct ct_data_s dyn_dtree[2*D_CODES+1]; /* distance tree */
471 struct ct_data_s bl_tree[2*BL_CODES+1]; /* Huffman tree for bit lengths */
472
473 struct tree_desc_s l_desc; /* desc. for literal tree */
474 struct tree_desc_s d_desc; /* desc. for distance tree */
475 struct tree_desc_s bl_desc; /* desc. for bit length tree */
476
477 ush bl_count[MAX_BITS+1];
478 /* number of codes at each bit length for an optimal tree */
479
480 int heap[2*L_CODES+1]; /* heap used to build the Huffman trees */
481 int heap_len; /* number of elements in the heap */
482 int heap_max; /* element of largest frequency */
483 /* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used.
484 * The same heap array is used to build all trees.
485 */
486
487 uch depth[2*L_CODES+1];
488 /* Depth of each subtree used as tie breaker for trees of equal frequency
489 */
490
491 uchf *l_buf; /* buffer for literals or lengths */
492
493 uInt lit_bufsize;
494 /* Size of match buffer for literals/lengths. There are 4 reasons for
495 * limiting lit_bufsize to 64K:
496 * - frequencies can be kept in 16 bit counters
497 * - if compression is not successful for the first block, all input
498 * data is still in the window so we can still emit a stored block even
499 * when input comes from standard input. (This can also be done for
500 * all blocks if lit_bufsize is not greater than 32K.)
501 * - if compression is not successful for a file smaller than 64K, we can
502 * even emit a stored file instead of a stored block (saving 5 bytes).
503 * This is applicable only for zip (not gzip or zlib).
504 * - creating new Huffman trees less frequently may not provide fast
505 * adaptation to changes in the input data statistics. (Take for
506 * example a binary file with poorly compressible code followed by
507 * a highly compressible string table.) Smaller buffer sizes give
508 * fast adaptation but have of course the overhead of transmitting
509 * trees more frequently.
510 * - I can't count above 4
511 */
512
513 uInt last_lit; /* running index in l_buf */
514
515 ushf *d_buf;
516 /* Buffer for distances. To simplify the code, d_buf and l_buf have
517 * the same number of elements. To use different lengths, an extra flag
518 * array would be necessary.
519 */
520
521 ulg opt_len; /* bit length of current block with optimal trees */
522 ulg static_len; /* bit length of current block with static trees */
523 uInt matches; /* number of string matches in current block */
524 int last_eob_len; /* bit length of EOB code for last block */
525
526 #ifdef DEBUG_ZLIB
527 ulg compressed_len; /* total bit length of compressed file mod 2^32 */
528 ulg bits_sent; /* bit length of compressed data sent mod 2^32 */
529 #endif
530
531 ush bi_buf;
532 /* Output buffer. bits are inserted starting at the bottom (least
533 * significant bits).
534 */
535 int bi_valid;
536 /* Number of valid bits in bi_buf. All bits above the last valid bit
537 * are always zero.
538 */
539
540 } FAR deflate_state;
541
542 /* Output a byte on the stream.
543 * IN assertion: there is enough room in pending_buf.
544 */
545 #define put_byte(s, c) {s->pending_buf[s->pending++] = (c);}
546
547
548 #define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
549 /* Minimum amount of lookahead, except at the end of the input file.
550 * See deflate.c for comments about the MIN_MATCH+1.
551 */
552
553 #define MAX_DIST(s) ((s)->w_size-MIN_LOOKAHEAD)
554 /* In order to simplify the code, particularly on 16 bit machines, match
555 * distances are limited to MAX_DIST instead of WSIZE.
556 */
557
558 /* in trees.c */
559 void _tr_init OF((deflate_state *s));
560 int _tr_tally OF((deflate_state *s, unsigned dist, unsigned lc));
561 void _tr_flush_block OF((deflate_state *s, charf *buf, ulg stored_len,
562 int eof));
563 void _tr_align OF((deflate_state *s));
564 void _tr_stored_block OF((deflate_state *s, charf *buf, ulg stored_len,
565 int eof));
566
567 #define d_code(dist) \
568 ((dist) < 256 ? _dist_code[dist] : _dist_code[256+((dist)>>7)])
569 /* Mapping from a distance to a distance code. dist is the distance - 1 and
570 * must not have side effects. _dist_code[256] and _dist_code[257] are never
571 * used.
572 */
573
574 #ifndef DEBUG_ZLIB
575 /* Inline versions of _tr_tally for speed: */
576
577 #if defined(GEN_TREES_H) || !defined(STDC)
578 extern uch _length_code[];
579 extern uch _dist_code[];
580 #else
581 extern const uch _length_code[];
582 extern const uch _dist_code[];
583 #endif
584
585 # define _tr_tally_lit(s, c, flush) \
586 { uch cc = (c); \
587 s->d_buf[s->last_lit] = 0; \
588 s->l_buf[s->last_lit++] = cc; \
589 s->dyn_ltree[cc].Freq++; \
590 flush = (s->last_lit == s->lit_bufsize-1); \
591 }
592 # define _tr_tally_dist(s, distance, length, flush) \
593 { uch len = (length); \
594 ush dist = (distance); \
595 s->d_buf[s->last_lit] = dist; \
596 s->l_buf[s->last_lit++] = len; \
597 dist--; \
598 s->dyn_ltree[_length_code[len]+LITERALS+1].Freq++; \
599 s->dyn_dtree[d_code(dist)].Freq++; \
600 flush = (s->last_lit == s->lit_bufsize-1); \
601 }
602 #else
603 # define _tr_tally_lit(s, c, flush) flush = _tr_tally(s, 0, c)
604 # define _tr_tally_dist(s, distance, length, flush) \
605 flush = _tr_tally(s, distance, length)
606 #endif
607
608 #endif
609 /* --- deflate.h */
610
611 /* +++ deflate.c */
612 /* deflate.c -- compress data using the deflation algorithm
613 * Copyright (C) 1995-2002 Jean-loup Gailly.
614 * For conditions of distribution and use, see copyright notice in zlib.h
615 */
616
617 /*
618 * ALGORITHM
619 *
620 * The "deflation" process depends on being able to identify portions
621 * of the input text which are identical to earlier input (within a
622 * sliding window trailing behind the input currently being processed).
623 *
624 * The most straightforward technique turns out to be the fastest for
625 * most input files: try all possible matches and select the longest.
626 * The key feature of this algorithm is that insertions into the string
627 * dictionary are very simple and thus fast, and deletions are avoided
628 * completely. Insertions are performed at each input character, whereas
629 * string matches are performed only when the previous match ends. So it
630 * is preferable to spend more time in matches to allow very fast string
631 * insertions and avoid deletions. The matching algorithm for small
632 * strings is inspired from that of Rabin & Karp. A brute force approach
633 * is used to find longer strings when a small match has been found.
634 * A similar algorithm is used in comic (by Jan-Mark Wams) and freeze
635 * (by Leonid Broukhis).
636 * A previous version of this file used a more sophisticated algorithm
637 * (by Fiala and Greene) which is guaranteed to run in linear amortized
638 * time, but has a larger average cost, uses more memory and is patented.
639 * However the F&G algorithm may be faster for some highly redundant
640 * files if the parameter max_chain_length (described below) is too large.
641 *
642 * ACKNOWLEDGEMENTS
643 *
644 * The idea of lazy evaluation of matches is due to Jan-Mark Wams, and
645 * I found it in 'freeze' written by Leonid Broukhis.
646 * Thanks to many people for bug reports and testing.
647 *
648 * REFERENCES
649 *
650 * Deutsch, L.P.,"DEFLATE Compressed Data Format Specification".
651 * Available in ftp://ds.internic.net/rfc/rfc1951.txt
652 *
653 * A description of the Rabin and Karp algorithm is given in the book
654 * "Algorithms" by R. Sedgewick, Addison-Wesley, p252.
655 *
656 * Fiala,E.R., and Greene,D.H.
657 * Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595
658 *
659 */
660
661 /* @(#) $Id: zlib.c,v 1.9 2002/11/28 00:56:55 lindak Exp $ */
662
663 /* #include "deflate.h" */
664
665 const char deflate_copyright[] =
666 " deflate 1.1.4 Copyright 1995-2002 Jean-loup Gailly ";
667 /*
668 If you use the zlib library in a product, an acknowledgment is welcome
669 in the documentation of your product. If for some reason you cannot
670 include such an acknowledgment, I would appreciate that you keep this
671 copyright string in the executable of your product.
672 */
673
674 /* ===========================================================================
675 * Function prototypes.
676 */
677 typedef enum {
678 need_more, /* block not completed, need more input or more output */
679 block_done, /* block flush performed */
680 finish_started, /* finish started, need only more output at next deflate */
681 finish_done /* finish done, accept no more input or output */
682 } block_state;
683
684 typedef block_state (*compress_func) OF((deflate_state *s, int flush));
685 /* Compression function. Returns the block state after the call. */
686
687 local void fill_window OF((deflate_state *s));
688 local block_state deflate_stored OF((deflate_state *s, int flush));
689 local block_state deflate_fast OF((deflate_state *s, int flush));
690 local block_state deflate_slow OF((deflate_state *s, int flush));
691 local void lm_init OF((deflate_state *s));
692 local void putShortMSB OF((deflate_state *s, uInt b));
693 local void flush_pending OF((z_streamp strm));
694 local int read_buf OF((z_streamp strm, Bytef *buf, unsigned size));
695 #ifdef ASMV
696 void match_init OF((void)); /* asm code initialization */
697 uInt longest_match OF((deflate_state *s, IPos cur_match));
698 #else
699 local uInt longest_match OF((deflate_state *s, IPos cur_match));
700 #endif
701
702 #ifdef DEBUG_ZLIB
703 local void check_match OF((deflate_state *s, IPos start, IPos match,
704 int length));
705 #endif
706
707 /* ===========================================================================
708 * Local data
709 */
710
711 #define NIL 0
712 /* Tail of hash chains */
713
714 #ifndef TOO_FAR
715 # define TOO_FAR 4096
716 #endif
717 /* Matches of length 3 are discarded if their distance exceeds TOO_FAR */
718
719 #define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
720 /* Minimum amount of lookahead, except at the end of the input file.
721 * See deflate.c for comments about the MIN_MATCH+1.
722 */
723
724 /* Values for max_lazy_match, good_match and max_chain_length, depending on
725 * the desired pack level (0..9). The values given below have been tuned to
726 * exclude worst case performance for pathological files. Better values may be
727 * found for specific files.
728 */
729 typedef struct config_s {
730 ush good_length; /* reduce lazy search above this match length */
731 ush max_lazy; /* do not perform lazy search above this match length */
732 ush nice_length; /* quit search above this match length */
733 ush max_chain;
734 compress_func func;
735 } config;
736
737 local const config configuration_table[10] = {
738 /* good lazy nice chain */
739 /* 0 */ {0, 0, 0, 0, deflate_stored}, /* store only */
740 /* 1 */ {4, 4, 8, 4, deflate_fast}, /* maximum speed, no lazy matches */
741 /* 2 */ {4, 5, 16, 8, deflate_fast},
742 /* 3 */ {4, 6, 32, 32, deflate_fast},
743
744 /* 4 */ {4, 4, 16, 16, deflate_slow}, /* lazy matches */
745 /* 5 */ {8, 16, 32, 32, deflate_slow},
746 /* 6 */ {8, 16, 128, 128, deflate_slow},
747 /* 7 */ {8, 32, 128, 256, deflate_slow},
748 /* 8 */ {32, 128, 258, 1024, deflate_slow},
749 /* 9 */ {32, 258, 258, 4096, deflate_slow}}; /* maximum compression */
750
751 /* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4
752 * For deflate_fast() (levels <= 3) good is ignored and lazy has a different
753 * meaning.
754 */
755
756 #define EQUAL 0
757 /* result of memcmp for equal strings */
758
759 #ifndef NO_DUMMY_DECL
760 struct static_tree_desc_s {int dummy;}; /* for buggy compilers */
761 #endif
762
763 /* ===========================================================================
764 * Update a hash value with the given input byte
765 * IN assertion: all calls to to UPDATE_HASH are made with consecutive
766 * input characters, so that a running hash key can be computed from the
767 * previous key instead of complete recalculation each time.
768 */
769 #define UPDATE_HASH(s,h,c) (h = (((h)<<s->hash_shift) ^ (c)) & s->hash_mask)
770
771
772 /* ===========================================================================
773 * Insert string str in the dictionary and set match_head to the previous head
774 * of the hash chain (the most recent string with same hash key). Return
775 * the previous length of the hash chain.
776 * If this file is compiled with -DFASTEST, the compression level is forced
777 * to 1, and no hash chains are maintained.
778 * IN assertion: all calls to to INSERT_STRING are made with consecutive
779 * input characters and the first MIN_MATCH bytes of str are valid
780 * (except for the last MIN_MATCH-1 bytes of the input file).
781 */
782 #ifdef FASTEST
783 #define INSERT_STRING(s, str, match_head) \
784 (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \
785 match_head = s->head[s->ins_h], \
786 s->head[s->ins_h] = (Pos)(str))
787 #else
788 #define INSERT_STRING(s, str, match_head) \
789 (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \
790 s->prev[(str) & s->w_mask] = match_head = s->head[s->ins_h], \
791 s->head[s->ins_h] = (Pos)(str))
792 #endif
793
794 /* ===========================================================================
795 * Initialize the hash table (avoiding 64K overflow for 16 bit systems).
796 * prev[] will be initialized on the fly.
797 */
798 #define CLEAR_HASH(s) \
799 s->head[s->hash_size-1] = NIL; \
800 zmemzero((Bytef *)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head));
801
802 /* ========================================================================= */
803 int ZEXPORT deflateInit_(strm, level, version, stream_size)
804 z_streamp strm;
805 int level;
806 const char *version;
807 int stream_size;
808 {
809 return deflateInit2_(strm, level, Z_DEFLATED, MAX_WBITS, DEF_MEM_LEVEL,
810 Z_DEFAULT_STRATEGY, version, stream_size);
811 /* To do: ignore strm->next_in if we use it as window */
812 }
813
814 /* ========================================================================= */
815 int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
816 version, stream_size)
817 z_streamp strm;
818 int level;
819 int method;
820 int windowBits;
821 int memLevel;
822 int strategy;
823 const char *version;
824 int stream_size;
825 {
826 deflate_state *s;
827 int noheader = 0;
828 static const char* my_version = ZLIB_VERSION;
829
830 ushf *overlay;
831 /* We overlay pending_buf and d_buf+l_buf. This works since the average
832 * output size for (length,distance) codes is <= 24 bits.
833 */
834
835 if (version == Z_NULL || version[0] != my_version[0] ||
836 stream_size != sizeof(z_stream)) {
837 return Z_VERSION_ERROR;
838 }
839 if (strm == Z_NULL) return Z_STREAM_ERROR;
840
841 strm->msg = Z_NULL;
842 #ifndef NO_ZCFUNCS
843 if (strm->zalloc == Z_NULL) {
844 strm->zalloc = zcalloc;
845 strm->opaque = (voidpf)0;
846 }
847 if (strm->zfree == Z_NULL) strm->zfree = zcfree;
848 #endif
849
850 if (level == Z_DEFAULT_COMPRESSION) level = 6;
851 #ifdef FASTEST
852 level = 1;
853 #endif
854
855 if (windowBits < 0) { /* undocumented feature: suppress zlib header */
856 noheader = 1;
857 windowBits = -windowBits;
858 }
859 if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED ||
860 windowBits < 9 || windowBits > 15 || level < 0 || level > 9 ||
861 strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
862 return Z_STREAM_ERROR;
863 }
864 s = (deflate_state *) ZALLOC(strm, 1, sizeof(deflate_state));
865 if (s == Z_NULL) return Z_MEM_ERROR;
866 strm->state = (struct internal_state FAR *)s;
867 s->strm = strm;
868
869 s->noheader = noheader;
870 s->w_bits = windowBits;
871 s->w_size = 1 << s->w_bits;
872 s->w_mask = s->w_size - 1;
873
874 s->hash_bits = memLevel + 7;
875 s->hash_size = 1 << s->hash_bits;
876 s->hash_mask = s->hash_size - 1;
877 s->hash_shift = ((s->hash_bits+MIN_MATCH-1)/MIN_MATCH);
878
879 s->window = (Bytef *) ZALLOC(strm, s->w_size, 2*sizeof(Byte));
880 s->prev = (Posf *) ZALLOC(strm, s->w_size, sizeof(Pos));
881 s->head = (Posf *) ZALLOC(strm, s->hash_size, sizeof(Pos));
882
883 s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */
884
885 overlay = (ushf *) ZALLOC(strm, s->lit_bufsize, sizeof(ush)+2);
886 s->pending_buf = (uchf *) overlay;
887 s->pending_buf_size = (ulg)s->lit_bufsize * (sizeof(ush)+2L);
888
889 if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL ||
890 s->pending_buf == Z_NULL) {
891 strm->msg = (char*)ERR_MSG(Z_MEM_ERROR);
892 deflateEnd (strm);
893 return Z_MEM_ERROR;
894 }
895 s->d_buf = overlay + s->lit_bufsize/sizeof(ush);
896 s->l_buf = s->pending_buf + (1+sizeof(ush))*s->lit_bufsize;
897
898 s->level = level;
899 s->strategy = strategy;
900 s->method = (Byte)method;
901
902 return deflateReset(strm);
903 }
904
905 /* ========================================================================= */
906 int ZEXPORT deflateSetDictionary (strm, dictionary, dictLength)
907 z_streamp strm;
908 const Bytef *dictionary;
909 uInt dictLength;
910 {
911 deflate_state *s;
912 uInt length = dictLength;
913 uInt n;
914 IPos hash_head = 0;
915
916 if (strm == Z_NULL || strm->state == Z_NULL || dictionary == Z_NULL ||
917 ((deflate_state*)strm->state)->status != INIT_STATE) return Z_STREAM_ERROR;
918
919 s = (deflate_state*)strm->state;
920 strm->adler = adler32(strm->adler, dictionary, dictLength);
921
922 if (length < MIN_MATCH) return Z_OK;
923 if (length > MAX_DIST(s)) {
924 length = MAX_DIST(s);
925 #ifndef USE_DICT_HEAD
926 dictionary += dictLength - length; /* use the tail of the dictionary */
927 #endif
928 }
929 zmemcpy(s->window, dictionary, length);
930 s->strstart = length;
931 s->block_start = (long)length;
932
933 /* Insert all strings in the hash table (except for the last two bytes).
934 * s->lookahead stays null, so s->ins_h will be recomputed at the next
935 * call of fill_window.
936 */
937 s->ins_h = s->window[0];
938 UPDATE_HASH(s, s->ins_h, s->window[1]);
939 for (n = 0; n <= length - MIN_MATCH; n++) {
940 INSERT_STRING(s, n, hash_head);
941 }
942 if (hash_head) hash_head = 0; /* to make compiler happy */
943 return Z_OK;
944 }
945
946 /* ========================================================================= */
947 int ZEXPORT deflateReset (strm)
948 z_streamp strm;
949 {
950 deflate_state *s;
951
952 if (strm == Z_NULL || strm->state == Z_NULL ||
953 strm->zalloc == Z_NULL || strm->zfree == Z_NULL) return Z_STREAM_ERROR;
954
955 strm->total_in = strm->total_out = 0;
956 strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */
957 strm->data_type = Z_UNKNOWN;
958
959 s = (deflate_state *)strm->state;
960 s->pending = 0;
961 s->pending_out = s->pending_buf;
962
963 if (s->noheader < 0) {
964 s->noheader = 0; /* was set to -1 by deflate(..., Z_FINISH); */
965 }
966 s->status = s->noheader ? BUSY_STATE : INIT_STATE;
967 strm->adler = 1;
968 s->last_flush = Z_NO_FLUSH;
969
970 _tr_init(s);
971 lm_init(s);
972
973 return Z_OK;
974 }
975
976 /* ========================================================================= */
977 int ZEXPORT deflateParams(strm, level, strategy)
978 z_streamp strm;
979 int level;
980 int strategy;
981 {
982 deflate_state *s;
983 compress_func func;
984 int err = Z_OK;
985
986 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
987 s = (deflate_state*)strm->state;
988
989 if (level == Z_DEFAULT_COMPRESSION) {
990 level = 6;
991 }
992 if (level < 0 || level > 9 || strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
993 return Z_STREAM_ERROR;
994 }
995 func = configuration_table[s->level].func;
996
997 if (func != configuration_table[level].func && strm->total_in != 0) {
998 /* Flush the last buffer: */
999 err = deflate(strm, Z_PARTIAL_FLUSH);
1000 }
1001 if (s->level != level) {
1002 s->level = level;
1003 s->max_lazy_match = configuration_table[level].max_lazy;
1004 s->good_match = configuration_table[level].good_length;
1005 s->nice_match = configuration_table[level].nice_length;
1006 s->max_chain_length = configuration_table[level].max_chain;
1007 }
1008 s->strategy = strategy;
1009 return err;
1010 }
1011
1012 /* =========================================================================
1013 * Put a short in the pending buffer. The 16-bit value is put in MSB order.
1014 * IN assertion: the stream state is correct and there is enough room in
1015 * pending_buf.
1016 */
1017 local void putShortMSB (s, b)
1018 deflate_state *s;
1019 uInt b;
1020 {
1021 put_byte(s, (Byte)(b >> 8));
1022 put_byte(s, (Byte)(b & 0xff));
1023 }
1024
1025 /* =========================================================================
1026 * Flush as much pending output as possible. All deflate() output goes
1027 * through this function so some applications may wish to modify it
1028 * to avoid allocating a large strm->next_out buffer and copying into it.
1029 * (See also read_buf()).
1030 */
1031 local void flush_pending(strm)
1032 z_streamp strm;
1033 {
1034 deflate_state* s = (deflate_state*)strm->state;
1035 unsigned len = s->pending;
1036
1037 if (len > strm->avail_out) len = strm->avail_out;
1038 if (len == 0) return;
1039
1040 zmemcpy(strm->next_out, s->pending_out, len);
1041 strm->next_out += len;
1042 s->pending_out += len;
1043 strm->total_out += len;
1044 strm->avail_out -= len;
1045 s->pending -= len;
1046 if (s->pending == 0) {
1047 s->pending_out = s->pending_buf;
1048 }
1049 }
1050
1051 /* ========================================================================= */
1052 int ZEXPORT deflate (strm, flush)
1053 z_streamp strm;
1054 int flush;
1055 {
1056 int old_flush; /* value of flush param for previous deflate call */
1057 deflate_state *s;
1058
1059 if (strm == Z_NULL || strm->state == Z_NULL ||
1060 flush > Z_FINISH || flush < 0) {
1061 return Z_STREAM_ERROR;
1062 }
1063 s = (deflate_state*)strm->state;
1064
1065 if (strm->next_out == Z_NULL ||
1066 (strm->next_in == Z_NULL && strm->avail_in != 0) ||
1067 (s->status == FINISH_STATE && flush != Z_FINISH)) {
1068 ERR_RETURN(strm, Z_STREAM_ERROR);
1069 }
1070 if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR);
1071
1072 s->strm = strm; /* just in case */
1073 old_flush = s->last_flush;
1074 s->last_flush = flush;
1075
1076 /* Write the zlib header */
1077 if (s->status == INIT_STATE) {
1078
1079 uInt header = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8;
1080 uInt level_flags = (s->level-1) >> 1;
1081
1082 if (level_flags > 3) level_flags = 3;
1083 header |= (level_flags << 6);
1084 if (s->strstart != 0) header |= PRESET_DICT;
1085 header += 31 - (header % 31);
1086
1087 s->status = BUSY_STATE;
1088 putShortMSB(s, header);
1089
1090 /* Save the adler32 of the preset dictionary: */
1091 if (s->strstart != 0) {
1092 putShortMSB(s, (uInt)(strm->adler >> 16));
1093 putShortMSB(s, (uInt)(strm->adler & 0xffff));
1094 }
1095 strm->adler = 1L;
1096 }
1097
1098 /* Flush as much pending output as possible */
1099 if (s->pending != 0) {
1100 flush_pending(strm);
1101 if (strm->avail_out == 0) {
1102 /* Since avail_out is 0, deflate will be called again with
1103 * more output space, but possibly with both pending and
1104 * avail_in equal to zero. There won't be anything to do,
1105 * but this is not an error situation so make sure we
1106 * return OK instead of BUF_ERROR at next call of deflate:
1107 */
1108 s->last_flush = -1;
1109 return Z_OK;
1110 }
1111
1112 /* Make sure there is something to do and avoid duplicate consecutive
1113 * flushes. For repeated and useless calls with Z_FINISH, we keep
1114 * returning Z_STREAM_END instead of Z_BUFF_ERROR.
1115 */
1116 } else if (strm->avail_in == 0 && flush <= old_flush &&
1117 flush != Z_FINISH) {
1118 ERR_RETURN(strm, Z_BUF_ERROR);
1119 }
1120
1121 /* User must not provide more input after the first FINISH: */
1122 if (s->status == FINISH_STATE && strm->avail_in != 0) {
1123 ERR_RETURN(strm, Z_BUF_ERROR);
1124 }
1125
1126 /* Start a new block or continue the current one.
1127 */
1128 if (strm->avail_in != 0 || s->lookahead != 0 ||
1129 (flush != Z_NO_FLUSH && s->status != FINISH_STATE)) {
1130 block_state bstate;
1131
1132 bstate = (*(configuration_table[s->level].func))(s, flush);
1133
1134 if (bstate == finish_started || bstate == finish_done) {
1135 s->status = FINISH_STATE;
1136 }
1137 if (bstate == need_more || bstate == finish_started) {
1138 if (strm->avail_out == 0) {
1139 s->last_flush = -1; /* avoid BUF_ERROR next call, see above */
1140 }
1141 return Z_OK;
1142 /* If flush != Z_NO_FLUSH && avail_out == 0, the next call
1143 * of deflate should use the same flush parameter to make sure
1144 * that the flush is complete. So we don't have to output an
1145 * empty block here, this will be done at next call. This also
1146 * ensures that for a very small output buffer, we emit at most
1147 * one empty block.
1148 */
1149 }
1150 if (bstate == block_done) {
1151 if (flush == Z_PARTIAL_FLUSH) {
1152 _tr_align(s);
1153 } else { /* FULL_FLUSH or SYNC_FLUSH */
1154 _tr_stored_block(s, (char*)0, 0L, 0);
1155 /* For a full flush, this empty block will be recognized
1156 * as a special marker by inflate_sync().
1157 */
1158 if (flush == Z_FULL_FLUSH) {
1159 CLEAR_HASH(s); /* forget history */
1160 }
1161 }
1162 flush_pending(strm);
1163 if (strm->avail_out == 0) {
1164 s->last_flush = -1; /* avoid BUF_ERROR at next call, see above */
1165 return Z_OK;
1166 }
1167 }
1168 }
1169 Assert(strm->avail_out > 0, "bug2");
1170
1171 if (flush != Z_FINISH) return Z_OK;
1172 if (s->noheader) return Z_STREAM_END;
1173
1174 /* Write the zlib trailer (adler32) */
1175 putShortMSB(s, (uInt)(strm->adler >> 16));
1176 putShortMSB(s, (uInt)(strm->adler & 0xffff));
1177 flush_pending(strm);
1178 /* If avail_out is zero, the application will call deflate again
1179 * to flush the rest.
1180 */
1181 s->noheader = -1; /* write the trailer only once! */
1182 return s->pending != 0 ? Z_OK : Z_STREAM_END;
1183 }
1184
1185 /* ========================================================================= */
1186 int ZEXPORT deflateEnd (strm)
1187 z_streamp strm;
1188 {
1189 deflate_state* s;
1190 int status;
1191
1192 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
1193
1194 s = (deflate_state*)strm->state;
1195 status = s->status;
1196 if (status != INIT_STATE && status != BUSY_STATE &&
1197 status != FINISH_STATE) {
1198 return Z_STREAM_ERROR;
1199 }
1200
1201 /* Deallocate in reverse order of allocations: */
1202 TRY_FREE(strm, s->pending_buf);
1203 TRY_FREE(strm, s->head);
1204 TRY_FREE(strm, s->prev);
1205 TRY_FREE(strm, s->window);
1206
1207 ZFREE(strm, s);
1208 strm->state = Z_NULL;
1209
1210 return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK;
1211 }
1212
1213 /* =========================================================================
1214 * Copy the source state to the destination state.
1215 * To simplify the source, this is not supported for 16-bit MSDOS (which
1216 * doesn't have enough memory anyway to duplicate compression states).
1217 */
1218 int ZEXPORT deflateCopy (dest, source)
1219 z_streamp dest;
1220 z_streamp source;
1221 {
1222 #ifdef MAXSEG_64K
1223 return Z_STREAM_ERROR;
1224 #else
1225 deflate_state *ds;
1226 deflate_state *ss;
1227 ushf *overlay;
1228
1229
1230 if (source == Z_NULL || dest == Z_NULL || source->state == Z_NULL) {
1231 return Z_STREAM_ERROR;
1232 }
1233
1234 ss = (deflate_state*)source->state;
1235
1236 *dest = *source;
1237
1238 ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state));
1239 if (ds == Z_NULL) return Z_MEM_ERROR;
1240 dest->state = (struct internal_state FAR *) ds;
1241 *ds = *ss;
1242 ds->strm = dest;
1243
1244 ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte));
1245 ds->prev = (Posf *) ZALLOC(dest, ds->w_size, sizeof(Pos));
1246 ds->head = (Posf *) ZALLOC(dest, ds->hash_size, sizeof(Pos));
1247 overlay = (ushf *) ZALLOC(dest, ds->lit_bufsize, sizeof(ush)+2);
1248 ds->pending_buf = (uchf *) overlay;
1249
1250 if (ds->window == Z_NULL || ds->prev == Z_NULL || ds->head == Z_NULL ||
1251 ds->pending_buf == Z_NULL) {
1252 deflateEnd (dest);
1253 return Z_MEM_ERROR;
1254 }
1255 /* following zmemcpy do not work for 16-bit MSDOS */
1256 zmemcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte));
1257 zmemcpy(ds->prev, ss->prev, ds->w_size * sizeof(Pos));
1258 zmemcpy(ds->head, ss->head, ds->hash_size * sizeof(Pos));
1259 zmemcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size);
1260
1261 ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf);
1262 ds->d_buf = overlay + ds->lit_bufsize/sizeof(ush);
1263 ds->l_buf = ds->pending_buf + (1+sizeof(ush))*ds->lit_bufsize;
1264
1265 ds->l_desc.dyn_tree = ds->dyn_ltree;
1266 ds->d_desc.dyn_tree = ds->dyn_dtree;
1267 ds->bl_desc.dyn_tree = ds->bl_tree;
1268
1269 return Z_OK;
1270 #endif
1271 }
1272
1273 /* ===========================================================================
1274 * Read a new buffer from the current input stream, update the adler32
1275 * and total number of bytes read. All deflate() input goes through
1276 * this function so some applications may wish to modify it to avoid
1277 * allocating a large strm->next_in buffer and copying from it.
1278 * (See also flush_pending()).
1279 */
1280 local int read_buf(strm, buf, size)
1281 z_streamp strm;
1282 Bytef *buf;
1283 unsigned size;
1284 {
1285 unsigned len = strm->avail_in;
1286
1287 if (len > size) len = size;
1288 if (len == 0) return 0;
1289
1290 strm->avail_in -= len;
1291
1292 if (!((deflate_state*)strm->state)->noheader) {
1293 strm->adler = adler32(strm->adler, strm->next_in, len);
1294 }
1295 zmemcpy(buf, strm->next_in, len);
1296 strm->next_in += len;
1297 strm->total_in += len;
1298
1299 return (int)len;
1300 }
1301
1302 /* ===========================================================================
1303 * Initialize the "longest match" routines for a new zlib stream
1304 */
1305 local void lm_init (s)
1306 deflate_state *s;
1307 {
1308 s->window_size = (ulg)2L*s->w_size;
1309
1310 CLEAR_HASH(s);
1311
1312 /* Set the default configuration parameters:
1313 */
1314 s->max_lazy_match = configuration_table[s->level].max_lazy;
1315 s->good_match = configuration_table[s->level].good_length;
1316 s->nice_match = configuration_table[s->level].nice_length;
1317 s->max_chain_length = configuration_table[s->level].max_chain;
1318
1319 s->strstart = 0;
1320 s->block_start = 0L;
1321 s->lookahead = 0;
1322 s->match_length = s->prev_length = MIN_MATCH-1;
1323 s->match_available = 0;
1324 s->ins_h = 0;
1325 #ifdef ASMV
1326 match_init(); /* initialize the asm code */
1327 #endif
1328 }
1329
1330 /* ===========================================================================
1331 * Set match_start to the longest match starting at the given string and
1332 * return its length. Matches shorter or equal to prev_length are discarded,
1333 * in which case the result is equal to prev_length and match_start is
1334 * garbage.
1335 * IN assertions: cur_match is the head of the hash chain for the current
1336 * string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1
1337 * OUT assertion: the match length is not greater than s->lookahead.
1338 */
1339 #ifndef ASMV
1340 /* For 80x86 and 680x0, an optimized version will be provided in match.asm or
1341 * match.S. The code will be functionally equivalent.
1342 */
1343 #ifndef FASTEST
1344 local uInt longest_match(s, cur_match)
1345 deflate_state *s;
1346 IPos cur_match; /* current match */
1347 {
1348 unsigned chain_length = s->max_chain_length;/* max hash chain length */
1349 register Bytef *scan = s->window + s->strstart; /* current string */
1350 register Bytef *match; /* matched string */
1351 register int len; /* length of current match */
1352 int best_len = s->prev_length; /* best match length so far */
1353 int nice_match = s->nice_match; /* stop if match long enough */
1354 IPos limit = s->strstart > (IPos)MAX_DIST(s) ?
1355 s->strstart - (IPos)MAX_DIST(s) : NIL;
1356 /* Stop when cur_match becomes <= limit. To simplify the code,
1357 * we prevent matches with the string of window index 0.
1358 */
1359 Posf *prev = s->prev;
1360 uInt wmask = s->w_mask;
1361
1362 #ifdef UNALIGNED_OK
1363 /* Compare two bytes at a time. Note: this is not always beneficial.
1364 * Try with and without -DUNALIGNED_OK to check.
1365 */
1366 register Bytef *strend = s->window + s->strstart + MAX_MATCH - 1;
1367 register ush scan_start = *(ushf*)scan;
1368 register ush scan_end = *(ushf*)(scan+best_len-1);
1369 #else
1370 register Bytef *strend = s->window + s->strstart + MAX_MATCH;
1371 register Byte scan_end1 = scan[best_len-1];
1372 register Byte scan_end = scan[best_len];
1373 #endif
1374
1375 /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
1376 * It is easy to get rid of this optimization if necessary.
1377 */
1378 Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");
1379
1380 /* Do not waste too much time if we already have a good match: */
1381 if (s->prev_length >= s->good_match) {
1382 chain_length >>= 2;
1383 }
1384 /* Do not look for matches beyond the end of the input. This is necessary
1385 * to make deflate deterministic.
1386 */
1387 if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;
1388
1389 Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
1390
1391 do {
1392 Assert(cur_match < s->strstart, "no future");
1393 match = s->window + cur_match;
1394
1395 /* Skip to next match if the match length cannot increase
1396 * or if the match length is less than 2:
1397 */
1398 #if (defined(UNALIGNED_OK) && MAX_MATCH == 258)
1399 /* This code assumes sizeof(unsigned short) == 2. Do not use
1400 * UNALIGNED_OK if your compiler uses a different size.
1401 */
1402 if (*(ushf*)(match+best_len-1) != scan_end ||
1403 *(ushf*)match != scan_start) continue;
1404
1405 /* It is not necessary to compare scan[2] and match[2] since they are
1406 * always equal when the other bytes match, given that the hash keys
1407 * are equal and that HASH_BITS >= 8. Compare 2 bytes at a time at
1408 * strstart+3, +5, ... up to strstart+257. We check for insufficient
1409 * lookahead only every 4th comparison; the 128th check will be made
1410 * at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is
1411 * necessary to put more guard bytes at the end of the window, or
1412 * to check more often for insufficient lookahead.
1413 */
1414 Assert(scan[2] == match[2], "scan[2]?");
1415 scan++, match++;
1416 do {
1417 } while (*(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1418 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1419 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1420 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1421 scan < strend);
1422 /* The funny "do {}" generates better code on most compilers */
1423
1424 /* Here, scan <= window+strstart+257 */
1425 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1426 if (*scan == *match) scan++;
1427
1428 len = (MAX_MATCH - 1) - (int)(strend-scan);
1429 scan = strend - (MAX_MATCH-1);
1430
1431 #else /* UNALIGNED_OK */
1432
1433 if (match[best_len] != scan_end ||
1434 match[best_len-1] != scan_end1 ||
1435 *match != *scan ||
1436 *++match != scan[1]) continue;
1437
1438 /* The check at best_len-1 can be removed because it will be made
1439 * again later. (This heuristic is not always a win.)
1440 * It is not necessary to compare scan[2] and match[2] since they
1441 * are always equal when the other bytes match, given that
1442 * the hash keys are equal and that HASH_BITS >= 8.
1443 */
1444 scan += 2, match++;
1445 Assert(*scan == *match, "match[2]?");
1446
1447 /* We check for insufficient lookahead only every 8th comparison;
1448 * the 256th check will be made at strstart+258.
1449 */
1450 do {
1451 } while (*++scan == *++match && *++scan == *++match &&
1452 *++scan == *++match && *++scan == *++match &&
1453 *++scan == *++match && *++scan == *++match &&
1454 *++scan == *++match && *++scan == *++match &&
1455 scan < strend);
1456
1457 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1458
1459 len = MAX_MATCH - (int)(strend - scan);
1460 scan = strend - MAX_MATCH;
1461
1462 #endif /* UNALIGNED_OK */
1463
1464 if (len > best_len) {
1465 s->match_start = cur_match;
1466 best_len = len;
1467 if (len >= nice_match) break;
1468 #ifdef UNALIGNED_OK
1469 scan_end = *(ushf*)(scan+best_len-1);
1470 #else
1471 scan_end1 = scan[best_len-1];
1472 scan_end = scan[best_len];
1473 #endif
1474 }
1475 } while ((cur_match = prev[cur_match & wmask]) > limit
1476 && --chain_length != 0);
1477
1478 if ((uInt)best_len <= s->lookahead) return (uInt)best_len;
1479 return s->lookahead;
1480 }
1481
1482 #else /* FASTEST */
1483 /* ---------------------------------------------------------------------------
1484 * Optimized version for level == 1 only
1485 */
1486 local uInt longest_match(s, cur_match)
1487 deflate_state *s;
1488 IPos cur_match; /* current match */
1489 {
1490 register Bytef *scan = s->window + s->strstart; /* current string */
1491 register Bytef *match; /* matched string */
1492 register int len; /* length of current match */
1493 register Bytef *strend = s->window + s->strstart + MAX_MATCH;
1494
1495 /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
1496 * It is easy to get rid of this optimization if necessary.
1497 */
1498 Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");
1499
1500 Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
1501
1502 Assert(cur_match < s->strstart, "no future");
1503
1504 match = s->window + cur_match;
1505
1506 /* Return failure if the match length is less than 2:
1507 */
1508 if (match[0] != scan[0] || match[1] != scan[1]) return MIN_MATCH-1;
1509
1510 /* The check at best_len-1 can be removed because it will be made
1511 * again later. (This heuristic is not always a win.)
1512 * It is not necessary to compare scan[2] and match[2] since they
1513 * are always equal when the other bytes match, given that
1514 * the hash keys are equal and that HASH_BITS >= 8.
1515 */
1516 scan += 2, match += 2;
1517 Assert(*scan == *match, "match[2]?");
1518
1519 /* We check for insufficient lookahead only every 8th comparison;
1520 * the 256th check will be made at strstart+258.
1521 */
1522 do {
1523 } while (*++scan == *++match && *++scan == *++match &&
1524 *++scan == *++match && *++scan == *++match &&
1525 *++scan == *++match && *++scan == *++match &&
1526 *++scan == *++match && *++scan == *++match &&
1527 scan < strend);
1528
1529 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1530
1531 len = MAX_MATCH - (int)(strend - scan);
1532
1533 if (len < MIN_MATCH) return MIN_MATCH - 1;
1534
1535 s->match_start = cur_match;
1536 return len <= s->lookahead ? len : s->lookahead;
1537 }
1538 #endif /* FASTEST */
1539 #endif /* ASMV */
1540
1541 #ifdef DEBUG_ZLIB
1542 /* ===========================================================================
1543 * Check that the match at match_start is indeed a match.
1544 */
1545 local void check_match(s, start, match, length)
1546 deflate_state *s;
1547 IPos start, match;
1548 int length;
1549 {
1550 /* check that the match is indeed a match */
1551 if (zmemcmp(s->window + match,
1552 s->window + start, length) != EQUAL) {
1553 fprintf(stderr, " start %u, match %u, length %d\n",
1554 start, match, length);
1555 do {
1556 fprintf(stderr, "%c%c", s->window[match++], s->window[start++]);
1557 } while (--length != 0);
1558 z_error("invalid match");
1559 }
1560 if (z_verbose > 1) {
1561 fprintf(stderr,"\\[%d,%d]", start-match, length);
1562 do { putc(s->window[start++], stderr); } while (--length != 0);
1563 }
1564 }
1565 #else
1566 # define check_match(s, start, match, length)
1567 #endif
1568
1569 /* ===========================================================================
1570 * Fill the window when the lookahead becomes insufficient.
1571 * Updates strstart and lookahead.
1572 *
1573 * IN assertion: lookahead < MIN_LOOKAHEAD
1574 * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD
1575 * At least one byte has been read, or avail_in == 0; reads are
1576 * performed for at least two bytes (required for the zip translate_eol
1577 * option -- not supported here).
1578 */
1579 local void fill_window(s)
1580 deflate_state *s;
1581 {
1582 register unsigned n, m;
1583 register Posf *p;
1584 unsigned more; /* Amount of free space at the end of the window. */
1585 uInt wsize = s->w_size;
1586
1587 do {
1588 more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart);
1589
1590 /* Deal with !@#$% 64K limit: */
1591 if (more == 0 && s->strstart == 0 && s->lookahead == 0) {
1592 more = wsize;
1593
1594 } else if (more == (unsigned)(-1)) {
1595 /* Very unlikely, but possible on 16 bit machine if strstart == 0
1596 * and lookahead == 1 (input done one byte at time)
1597 */
1598 more--;
1599
1600 /* If the window is almost full and there is insufficient lookahead,
1601 * move the upper half to the lower one to make room in the upper half.
1602 */
1603 } else if (s->strstart >= wsize+MAX_DIST(s)) {
1604
1605 zmemcpy(s->window, s->window+wsize, (unsigned)wsize);
1606 s->match_start -= wsize;
1607 s->strstart -= wsize; /* we now have strstart >= MAX_DIST */
1608 s->block_start -= (long) wsize;
1609
1610 /* Slide the hash table (could be avoided with 32 bit values
1611 at the expense of memory usage). We slide even when level == 0
1612 to keep the hash table consistent if we switch back to level > 0
1613 later. (Using level 0 permanently is not an optimal usage of
1614 zlib, so we don't care about this pathological case.)
1615 */
1616 n = s->hash_size;
1617 p = &s->head[n];
1618 do {
1619 m = *--p;
1620 *p = (Pos)(m >= wsize ? m-wsize : NIL);
1621 } while (--n);
1622
1623 n = wsize;
1624 #ifndef FASTEST
1625 p = &s->prev[n];
1626 do {
1627 m = *--p;
1628 *p = (Pos)(m >= wsize ? m-wsize : NIL);
1629 /* If n is not on any hash chain, prev[n] is garbage but
1630 * its value will never be used.
1631 */
1632 } while (--n);
1633 #endif
1634 more += wsize;
1635 }
1636 if (s->strm->avail_in == 0) return;
1637
1638 /* If there was no sliding:
1639 * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 &&
1640 * more == window_size - lookahead - strstart
1641 * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1)
1642 * => more >= window_size - 2*WSIZE + 2
1643 * In the BIG_MEM or MMAP case (not yet supported),
1644 * window_size == input_size + MIN_LOOKAHEAD &&
1645 * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD.
1646 * Otherwise, window_size == 2*WSIZE so more >= 2.
1647 * If there was sliding, more >= WSIZE. So in all cases, more >= 2.
1648 */
1649 Assert(more >= 2, "more < 2");
1650
1651 n = read_buf(s->strm, s->window + s->strstart + s->lookahead, more);
1652 s->lookahead += n;
1653
1654 /* Initialize the hash value now that we have some input: */
1655 if (s->lookahead >= MIN_MATCH) {
1656 s->ins_h = s->window[s->strstart];
1657 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
1658 #if MIN_MATCH != 3
1659 Call UPDATE_HASH() MIN_MATCH-3 more times
1660 #endif
1661 }
1662 /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage,
1663 * but this is not important since only literal bytes will be emitted.
1664 */
1665
1666 } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0);
1667 }
1668
1669 /* ===========================================================================
1670 * Flush the current block, with given end-of-file flag.
1671 * IN assertion: strstart is set to the end of the current match.
1672 */
1673 #define FLUSH_BLOCK_ONLY(s, eof) { \
1674 _tr_flush_block(s, (s->block_start >= 0L ? \
1675 (charf *)&s->window[(unsigned)s->block_start] : \
1676 (charf *)Z_NULL), \
1677 (ulg)((long)s->strstart - s->block_start), \
1678 (eof)); \
1679 s->block_start = s->strstart; \
1680 flush_pending(s->strm); \
1681 Tracev((stderr,"[FLUSH]")); \
1682 }
1683
1684 /* Same but force premature exit if necessary. */
1685 #define FLUSH_BLOCK(s, eof) { \
1686 FLUSH_BLOCK_ONLY(s, eof); \
1687 if (s->strm->avail_out == 0) return (eof) ? finish_started : need_more; \
1688 }
1689
1690 /* ===========================================================================
1691 * Copy without compression as much as possible from the input stream, return
1692 * the current block state.
1693 * This function does not insert new strings in the dictionary since
1694 * uncompressible data is probably not useful. This function is used
1695 * only for the level=0 compression option.
1696 * NOTE: this function should be optimized to avoid extra copying from
1697 * window to pending_buf.
1698 */
1699 local block_state deflate_stored(s, flush)
1700 deflate_state *s;
1701 int flush;
1702 {
1703 /* Stored blocks are limited to 0xffff bytes, pending_buf is limited
1704 * to pending_buf_size, and each stored block has a 5 byte header:
1705 */
1706 ulg max_block_size = 0xffff;
1707 ulg max_start;
1708
1709 if (max_block_size > s->pending_buf_size - 5) {
1710 max_block_size = s->pending_buf_size - 5;
1711 }
1712
1713 /* Copy as much as possible from input to output: */
1714 for (;;) {
1715 /* Fill the window as much as possible: */
1716 if (s->lookahead <= 1) {
1717
1718 Assert(s->strstart < s->w_size+MAX_DIST(s) ||
1719 s->block_start >= (long)s->w_size, "slide too late");
1720
1721 fill_window(s);
1722 if (s->lookahead == 0 && flush == Z_NO_FLUSH) return need_more;
1723
1724 if (s->lookahead == 0) break; /* flush the current block */
1725 }
1726 Assert(s->block_start >= 0L, "block gone");
1727
1728 s->strstart += s->lookahead;
1729 s->lookahead = 0;
1730
1731 /* Emit a stored block if pending_buf will be full: */
1732 max_start = s->block_start + max_block_size;
1733 if (s->strstart == 0 || (ulg)s->strstart >= max_start) {
1734 /* strstart == 0 is possible when wraparound on 16-bit machine */
1735 s->lookahead = (uInt)(s->strstart - max_start);
1736 s->strstart = (uInt)max_start;
1737 FLUSH_BLOCK(s, 0);
1738 }
1739 /* Flush if we may have to slide, otherwise block_start may become
1740 * negative and the data will be gone:
1741 */
1742 if (s->strstart - (uInt)s->block_start >= MAX_DIST(s)) {
1743 FLUSH_BLOCK(s, 0);
1744 }
1745 }
1746 FLUSH_BLOCK(s, flush == Z_FINISH);
1747 return flush == Z_FINISH ? finish_done : block_done;
1748 }
1749
1750 /* ===========================================================================
1751 * Compress as much as possible from the input stream, return the current
1752 * block state.
1753 * This function does not perform lazy evaluation of matches and inserts
1754 * new strings in the dictionary only for unmatched strings or for short
1755 * matches. It is used only for the fast compression options.
1756 */
1757 local block_state deflate_fast(s, flush)
1758 deflate_state *s;
1759 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(s, flush)
1854 deflate_state *s;
1855 int flush;
1856 {
1857 IPos hash_head = NIL; /* head of hash chain */
1858 int bflush; /* set if current block must be flushed */
1859
1860 /* Process the input block. */
1861 for (;;) {
1862 /* Make sure that we always have enough lookahead, except
1863 * at the end of the input file. We need MAX_MATCH bytes
1864 * for the next match, plus MIN_MATCH bytes to insert the
1865 * string following the next match.
1866 */
1867 if (s->lookahead < MIN_LOOKAHEAD) {
1868 fill_window(s);
1869 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
1870 return need_more;
1871 }
1872 if (s->lookahead == 0) break; /* flush the current block */
1873 }
1874
1875 /* Insert the string window[strstart .. strstart+2] in the
1876 * dictionary, and set hash_head to the head of the hash chain:
1877 */
1878 if (s->lookahead >= MIN_MATCH) {
1879 INSERT_STRING(s, s->strstart, hash_head);
1880 }
1881
1882 /* Find the longest match, discarding those <= prev_length.
1883 */
1884 s->prev_length = s->match_length, s->prev_match = s->match_start;
1885 s->match_length = MIN_MATCH-1;
1886
1887 if (hash_head != NIL && s->prev_length < s->max_lazy_match &&
1888 s->strstart - hash_head <= MAX_DIST(s)) {
1889 /* To simplify the code, we prevent matches with the string
1890 * of window index 0 (in particular we have to avoid a match
1891 * of the string with itself at the start of the input file).
1892 */
1893 if (s->strategy != Z_HUFFMAN_ONLY) {
1894 s->match_length = longest_match (s, hash_head);
1895 }
1896 /* longest_match() sets match_start */
1897
1898 if (s->match_length <= 5 && (s->strategy == Z_FILTERED ||
1899 (s->match_length == MIN_MATCH &&
1900 s->strstart - s->match_start > TOO_FAR))) {
1901
1902 /* If prev_match is also MIN_MATCH, match_start is garbage
1903 * but we will ignore the current match anyway.
1904 */
1905 s->match_length = MIN_MATCH-1;
1906 }
1907 }
1908 /* If there was a match at the previous step and the current
1909 * match is not better, output the previous match:
1910 */
1911 if (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) {
1912 uInt max_insert = s->strstart + s->lookahead - MIN_MATCH;
1913 /* Do not insert strings in hash table beyond this. */
1914
1915 check_match(s, s->strstart-1, s->prev_match, s->prev_length);
1916
1917 _tr_tally_dist(s, s->strstart -1 - s->prev_match,
1918 s->prev_length - MIN_MATCH, bflush);
1919
1920 /* Insert in hash table all strings up to the end of the match.
1921 * strstart-1 and strstart are already inserted. If there is not
1922 * enough lookahead, the last two strings are not inserted in
1923 * the hash table.
1924 */
1925 s->lookahead -= s->prev_length-1;
1926 s->prev_length -= 2;
1927 do {
1928 if (++s->strstart <= max_insert) {
1929 INSERT_STRING(s, s->strstart, hash_head);
1930 }
1931 } while (--s->prev_length != 0);
1932 s->match_available = 0;
1933 s->match_length = MIN_MATCH-1;
1934 s->strstart++;
1935
1936 if (bflush) FLUSH_BLOCK(s, 0);
1937
1938 } else if (s->match_available) {
1939 /* If there was no match at the previous position, output a
1940 * single literal. If there was a match but the current match
1941 * is longer, truncate the previous match to a single literal.
1942 */
1943 Tracevv((stderr,"%c", s->window[s->strstart-1]));
1944 _tr_tally_lit(s, s->window[s->strstart-1], bflush);
1945 if (bflush) {
1946 FLUSH_BLOCK_ONLY(s, 0);
1947 }
1948 s->strstart++;
1949 s->lookahead--;
1950 if (s->strm->avail_out == 0) return need_more;
1951 } else {
1952 /* There is no previous match to compare with, wait for
1953 * the next step to decide.
1954 */
1955 s->match_available = 1;
1956 s->strstart++;
1957 s->lookahead--;
1958 }
1959 }
1960 Assert (flush != Z_NO_FLUSH, "no flush?");
1961 if (s->match_available) {
1962 Tracevv((stderr,"%c", s->window[s->strstart-1]));
1963 _tr_tally_lit(s, s->window[s->strstart-1], bflush);
1964 s->match_available = 0;
1965 }
1966 FLUSH_BLOCK(s, flush == Z_FINISH);
1967 return flush == Z_FINISH ? finish_done : block_done;
1968 }
1969 /* --- deflate.c */
1970
1971 /* +++ trees.c */
1972 /* trees.c -- output deflated data using Huffman coding
1973 * Copyright (C) 1995-2002 Jean-loup Gailly
1974 * For conditions of distribution and use, see copyright notice in zlib.h
1975 */
1976
1977 /*
1978 * ALGORITHM
1979 *
1980 * The "deflation" process uses several Huffman trees. The more
1981 * common source values are represented by shorter bit sequences.
1982 *
1983 * Each code tree is stored in a compressed form which is itself
1984 * a Huffman encoding of the lengths of all the code strings (in
1985 * ascending order by source values). The actual code strings are
1986 * reconstructed from the lengths in the inflate process, as described
1987 * in the deflate specification.
1988 *
1989 * REFERENCES
1990 *
1991 * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification".
1992 * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc
1993 *
1994 * Storer, James A.
1995 * Data Compression: Methods and Theory, pp. 49-50.
1996 * Computer Science Press, 1988. ISBN 0-7167-8156-5.
1997 *
1998 * Sedgewick, R.
1999 * Algorithms, p290.
2000 * Addison-Wesley, 1983. ISBN 0-201-06672-6.
2001 */
2002
2003 /* @(#) $Id: zlib.c,v 1.9 2002/11/28 00:56:55 lindak Exp $ */
2004
2005 /* #define GEN_TREES_H */
2006
2007 /* #include "deflate.h" */
2008
2009 #ifdef DEBUG_ZLIB
2010 # include <ctype.h>
2011 #endif
2012
2013 /* ===========================================================================
2014 * Constants
2015 */
2016
2017 #define MAX_BL_BITS 7
2018 /* Bit length codes must not exceed MAX_BL_BITS bits */
2019
2020 #define END_BLOCK 256
2021 /* end of block literal code */
2022
2023 #define REP_3_6 16
2024 /* repeat previous bit length 3-6 times (2 bits of repeat count) */
2025
2026 #define REPZ_3_10 17
2027 /* repeat a zero length 3-10 times (3 bits of repeat count) */
2028
2029 #define REPZ_11_138 18
2030 /* repeat a zero length 11-138 times (7 bits of repeat count) */
2031
2032 local const int extra_lbits[LENGTH_CODES] /* extra bits for each length code */
2033 = {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};
2034
2035 local const int extra_dbits[D_CODES] /* extra bits for each distance code */
2036 = {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};
2037
2038 local const int extra_blbits[BL_CODES]/* extra bits for each bit length code */
2039 = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7};
2040
2041 local const uch bl_order[BL_CODES]
2042 = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15};
2043 /* The lengths of the bit length codes are sent in order of decreasing
2044 * probability, to avoid transmitting the lengths for unused bit length codes.
2045 */
2046
2047 #define Buf_size (8 * 2*sizeof(char))
2048 /* Number of bits used within bi_buf. (bi_buf might be implemented on
2049 * more than 16 bits on some systems.)
2050 */
2051
2052 /* ===========================================================================
2053 * Local data. These are initialized only once.
2054 */
2055
2056 #define DIST_CODE_LEN 512 /* see definition of array dist_code below */
2057
2058 #if defined(GEN_TREES_H) || !defined(STDC)
2059 /* non ANSI compilers may not accept trees.h */
2060
2061 local ct_data *static_ltree = Z_NULL;
2062 /* The static literal tree. Since the bit lengths are imposed, there is no
2063 * need for the L_CODES extra codes used during heap construction. However
2064 * The codes 286 and 287 are needed to build a canonical tree (see _tr_init
2065 * below).
2066 */
2067
2068 local ct_data *static_dtree = Z_NULL;
2069 /* The static distance tree. (Actually a trivial tree since all codes use
2070 * 5 bits.)
2071 */
2072
2073 uch *_dist_code = Z_NULL;
2074 /* Distance codes. The first 256 values correspond to the distances
2075 * 3 .. 258, the last 256 values correspond to the top 8 bits of
2076 * the 15 bit distances.
2077 */
2078
2079 uch *_length_code = Z_NULL;
2080 /* length code for each normalized match length (0 == MIN_MATCH) */
2081
2082 local int *base_length = Z_NULL;
2083 /* First normalized length for each code (0 = MIN_MATCH) */
2084
2085 local int *base_dist = Z_NULL;
2086 /* First normalized distance for each code (0 = distance of 1) */
2087
2088 #else
2089 /* +++ trees.h */
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
2218 /* --- trees.h */
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 {NULL, extra_lbits, LITERALS+1, L_CODES, MAX_BITS};
2231
2232 local static_tree_desc static_d_desc =
2233 {NULL, 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 int tr_static_init OF((z_streamp z));
2243 local void init_block OF((deflate_state *s));
2244 local void pqdownheap OF((deflate_state *s, ct_data *tree, int k));
2245 local void gen_bitlen OF((deflate_state *s, tree_desc *desc));
2246 local void gen_codes OF((ct_data *tree, int max_code, ushf *bl_count));
2247 local void build_tree OF((deflate_state *s, tree_desc *desc));
2248 local void scan_tree OF((deflate_state *s, ct_data *tree, int max_code));
2249 local void send_tree OF((deflate_state *s, ct_data *tree, int max_code));
2250 local int build_bl_tree OF((deflate_state *s));
2251 local void send_all_trees OF((deflate_state *s, int lcodes, int dcodes,
2252 int blcodes));
2253 local void compress_block OF((deflate_state *s, ct_data *ltree,
2254 ct_data *dtree));
2255 local void set_data_type OF((deflate_state *s));
2256 local unsigned bi_reverse OF((unsigned value, int length));
2257 local void bi_windup OF((deflate_state *s));
2258 local void bi_flush OF((deflate_state *s));
2259 local void copy_block OF((deflate_state *s, charf *buf, unsigned len,
2260 int header));
2261
2262 #ifdef GEN_TREES_H
2263 local void gen_trees_header OF((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 OF((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 #ifndef MAX
2334 #define MAX(a,b) (a >= b ? a : b)
2335 #endif
2336 /* the arguments must not have side effects */
2337
2338 typedef struct {
2339 ct_data static_ltree[L_CODES+2];
2340 ct_data static_dtree[D_CODES];
2341 uch _dist_code[DIST_CODE_LEN];
2342 uch _length_code[MAX_MATCH-MIN_MATCH+1];
2343 int base_length[LENGTH_CODES];
2344 int base_dist[D_CODES];
2345 } __used_to_be_static;
2346
2347 static __used_to_be_static *static_storage = Z_NULL;
2348
2349 /* ===========================================================================
2350 * Initialize the various 'constant' tables.
2351 */
2352 local int tr_static_init(
2353 z_streamp z)
2354 {
2355 #if defined(GEN_TREES_H) || !defined(STDC)
2356 static int static_init_done = 0;
2357 int n; /* iterates over tree elements */
2358 int bits; /* bit counter */
2359 int length; /* length value */
2360 int code; /* code value */
2361 int dist; /* distance index */
2362 ush bl_count[MAX_BITS+1];
2363 /* number of codes at each bit length for an optimal tree */
2364
2365 if (static_init_done) return;
2366
2367 /* allocate storage for static structures */
2368 if (static_storage == Z_NULL) {
2369 static_storage = (__used_to_be_static*)ZALLOC(z, 1, sizeof(__used_to_be_static));
2370 if (static_storage == Z_NULL)
2371 return Z_MEM_ERROR;
2372 }
2373
2374 static_ltree = static_storage->static_ltree;
2375 static_dtree = static_storage->static_dtree;
2376 _dist_code = static_storage->_dist_code;
2377 _length_code = static_storage->_length_code;
2378 base_length = static_storage->base_length;
2379 base_dist = static_storage->base_dist;
2380
2381 /* For some embedded targets, global variables are not initialized: */
2382 static_l_desc.static_tree = static_ltree;
2383 static_l_desc.extra_bits = extra_lbits;
2384 static_d_desc.static_tree = static_dtree;
2385 static_d_desc.extra_bits = extra_dbits;
2386 static_bl_desc.extra_bits = extra_blbits;
2387
2388 /* Initialize the mapping length (0..255) -> length code (0..28) */
2389 length = 0;
2390 for (code = 0; code < LENGTH_CODES-1; code++) {
2391 base_length[code] = length;
2392 for (n = 0; n < (1<<extra_lbits[code]); n++) {
2393 _length_code[length++] = (uch)code;
2394 }
2395 }
2396 Assert (length == 256, "tr_static_init: length != 256");
2397 /* Note that the length 255 (match length 258) can be represented
2398 * in two different ways: code 284 + 5 bits or code 285, so we
2399 * overwrite length_code[255] to use the best encoding:
2400 */
2401 _length_code[length-1] = (uch)code;
2402
2403 /* Initialize the mapping dist (0..32K) -> dist code (0..29) */
2404 dist = 0;
2405 for (code = 0 ; code < 16; code++) {
2406 base_dist[code] = dist;
2407 for (n = 0; n < (1<<extra_dbits[code]); n++) {
2408 _dist_code[dist++] = (uch)code;
2409 }
2410 }
2411 Assert (dist == 256, "tr_static_init: dist != 256");
2412 dist >>= 7; /* from now on, all distances are divided by 128 */
2413 for ( ; code < D_CODES; code++) {
2414 base_dist[code] = dist << 7;
2415 for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) {
2416 _dist_code[256 + dist++] = (uch)code;
2417 }
2418 }
2419 Assert (dist == 256, "tr_static_init: 256+dist != 512");
2420
2421 /* Construct the codes of the static literal tree */
2422 for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
2423 n = 0;
2424 while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++;
2425 while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++;
2426 while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++;
2427 while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++;
2428 /* Codes 286 and 287 do not exist, but we must include them in the
2429 * tree construction to get a canonical Huffman tree (longest code
2430 * all ones)
2431 */
2432 gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count);
2433
2434 /* The static distance tree is trivial: */
2435 for (n = 0; n < D_CODES; n++) {
2436 static_dtree[n].Len = 5;
2437 static_dtree[n].Code = bi_reverse((unsigned)n, 5);
2438 }
2439 static_init_done = 1;
2440
2441 # ifdef GEN_TREES_H
2442 gen_trees_header();
2443 # endif
2444 #endif /* defined(GEN_TREES_H) || !defined(STDC) */
2445 }
2446
2447 /* ===========================================================================
2448 * Genererate the file trees.h describing the static trees.
2449 */
2450 #ifdef GEN_TREES_H
2451 # ifndef DEBUG_ZLIB
2452 # include <stdio.h>
2453 # endif
2454
2455 # define SEPARATOR(i, last, width) \
2456 ((i) == (last)? "\n};\n\n" : \
2457 ((i) % (width) == (width)-1 ? ",\n" : ", "))
2458
2459 void gen_trees_header()
2460 {
2461 FILE *header = fopen("trees.h", "w");
2462 int i;
2463
2464 Assert (header != NULL, "Can't open trees.h");
2465 fprintf(header,
2466 "/* header created automatically with -DGEN_TREES_H */\n\n");
2467
2468 fprintf(header, "local const ct_data static_ltree[L_CODES+2] = {\n");
2469 for (i = 0; i < L_CODES+2; i++) {
2470 fprintf(header, "{{%3u},{%3u}}%s", static_ltree[i].Code,
2471 static_ltree[i].Len, SEPARATOR(i, L_CODES+1, 5));
2472 }
2473
2474 fprintf(header, "local const ct_data static_dtree[D_CODES] = {\n");
2475 for (i = 0; i < D_CODES; i++) {
2476 fprintf(header, "{{%2u},{%2u}}%s", static_dtree[i].Code,
2477 static_dtree[i].Len, SEPARATOR(i, D_CODES-1, 5));
2478 }
2479
2480 fprintf(header, "const uch _dist_code[DIST_CODE_LEN] = {\n");
2481 for (i = 0; i < DIST_CODE_LEN; i++) {
2482 fprintf(header, "%2u%s", _dist_code[i],
2483 SEPARATOR(i, DIST_CODE_LEN-1, 20));
2484 }
2485
2486 fprintf(header, "const uch _length_code[MAX_MATCH-MIN_MATCH+1]= {\n");
2487 for (i = 0; i < MAX_MATCH-MIN_MATCH+1; i++) {
2488 fprintf(header, "%2u%s", _length_code[i],
2489 SEPARATOR(i, MAX_MATCH-MIN_MATCH, 20));
2490 }
2491
2492 fprintf(header, "local const int base_length[LENGTH_CODES] = {\n");
2493 for (i = 0; i < LENGTH_CODES; i++) {
2494 fprintf(header, "%1u%s", base_length[i],
2495 SEPARATOR(i, LENGTH_CODES-1, 20));
2496 }
2497
2498 fprintf(header, "local const int base_dist[D_CODES] = {\n");
2499 for (i = 0; i < D_CODES; i++) {
2500 fprintf(header, "%5u%s", base_dist[i],
2501 SEPARATOR(i, D_CODES-1, 10));
2502 }
2503
2504 fclose(header);
2505 }
2506 #endif /* GEN_TREES_H */
2507
2508 /* ===========================================================================
2509 * Initialize the tree data structures for a new zlib stream.
2510 */
2511 void _tr_init(s)
2512 deflate_state *s;
2513 {
2514 tr_static_init(s->strm);
2515
2516 s->l_desc.dyn_tree = s->dyn_ltree;
2517 s->l_desc.stat_desc = &static_l_desc;
2518
2519 s->d_desc.dyn_tree = s->dyn_dtree;
2520 s->d_desc.stat_desc = &static_d_desc;
2521
2522 s->bl_desc.dyn_tree = s->bl_tree;
2523 s->bl_desc.stat_desc = &static_bl_desc;
2524
2525 s->bi_buf = 0;
2526 s->bi_valid = 0;
2527 s->last_eob_len = 8; /* enough lookahead for inflate */
2528 #ifdef DEBUG_ZLIB
2529 s->compressed_len = 0L;
2530 s->bits_sent = 0L;
2531 #endif
2532
2533 /* Initialize the first block of the first file: */
2534 init_block(s);
2535 }
2536
2537 /* ===========================================================================
2538 * Initialize a new block.
2539 */
2540 local void init_block(s)
2541 deflate_state *s;
2542 {
2543 int n; /* iterates over tree elements */
2544
2545 /* Initialize the trees. */
2546 for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0;
2547 for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0;
2548 for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0;
2549
2550 s->dyn_ltree[END_BLOCK].Freq = 1;
2551 s->opt_len = s->static_len = 0L;
2552 s->last_lit = s->matches = 0;
2553 }
2554
2555 #define SMALLEST 1
2556 /* Index within the heap array of least frequent node in the Huffman tree */
2557
2558
2559 /* ===========================================================================
2560 * Remove the smallest element from the heap and recreate the heap with
2561 * one less element. Updates heap and heap_len.
2562 */
2563 #define pqremove(s, tree, top) \
2564 {\
2565 top = s->heap[SMALLEST]; \
2566 s->heap[SMALLEST] = s->heap[s->heap_len--]; \
2567 pqdownheap(s, tree, SMALLEST); \
2568 }
2569
2570 /* ===========================================================================
2571 * Compares to subtrees, using the tree depth as tie breaker when
2572 * the subtrees have equal frequency. This minimizes the worst case length.
2573 */
2574 #define smaller(tree, n, m, depth) \
2575 (tree[n].Freq < tree[m].Freq || \
2576 (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m]))
2577
2578 /* ===========================================================================
2579 * Restore the heap property by moving down the tree starting at node k,
2580 * exchanging a node with the smallest of its two sons if necessary, stopping
2581 * when the heap property is re-established (each father smaller than its
2582 * two sons).
2583 */
2584 local void pqdownheap(s, tree, k)
2585 deflate_state *s;
2586 ct_data *tree; /* the tree to restore */
2587 int k; /* node to move down */
2588 {
2589 int v = s->heap[k];
2590 int j = k << 1; /* left son of k */
2591 while (j <= s->heap_len) {
2592 /* Set j to the smallest of the two sons: */
2593 if (j < s->heap_len &&
2594 smaller(tree, s->heap[j+1], s->heap[j], s->depth)) {
2595 j++;
2596 }
2597 /* Exit if v is smaller than both sons */
2598 if (smaller(tree, v, s->heap[j], s->depth)) break;
2599
2600 /* Exchange v with the smallest son */
2601 s->heap[k] = s->heap[j]; k = j;
2602
2603 /* And continue down the tree, setting j to the left son of k */
2604 j <<= 1;
2605 }
2606 s->heap[k] = v;
2607 }
2608
2609 /* ===========================================================================
2610 * Compute the optimal bit lengths for a tree and update the total bit length
2611 * for the current block.
2612 * IN assertion: the fields freq and dad are set, heap[heap_max] and
2613 * above are the tree nodes sorted by increasing frequency.
2614 * OUT assertions: the field len is set to the optimal bit length, the
2615 * array bl_count contains the frequencies for each bit length.
2616 * The length opt_len is updated; static_len is also updated if stree is
2617 * not null.
2618 */
2619 local void gen_bitlen(s, desc)
2620 deflate_state *s;
2621 tree_desc *desc; /* the tree descriptor */
2622 {
2623 ct_data *tree = desc->dyn_tree;
2624 int max_code = desc->max_code;
2625 const ct_data *stree = desc->stat_desc->static_tree;
2626 const intf *extra = desc->stat_desc->extra_bits;
2627 int base = desc->stat_desc->extra_base;
2628 int max_length = desc->stat_desc->max_length;
2629 int h; /* heap index */
2630 int n, m; /* iterate over the tree elements */
2631 int bits; /* bit length */
2632 int xbits; /* extra bits */
2633 ush f; /* frequency */
2634 int overflow = 0; /* number of elements with bit length too large */
2635
2636 for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0;
2637
2638 /* In a first pass, compute the optimal bit lengths (which may
2639 * overflow in the case of the bit length tree).
2640 */
2641 tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */
2642
2643 for (h = s->heap_max+1; h < HEAP_SIZE; h++) {
2644 n = s->heap[h];
2645 bits = tree[tree[n].Dad].Len + 1;
2646 if (bits > max_length) bits = max_length, overflow++;
2647 tree[n].Len = (ush)bits;
2648 /* We overwrite tree[n].Dad which is no longer needed */
2649
2650 if (n > max_code) continue; /* not a leaf node */
2651
2652 s->bl_count[bits]++;
2653 xbits = 0;
2654 if (n >= base) xbits = extra[n-base];
2655 f = tree[n].Freq;
2656 s->opt_len += (ulg)f * (bits + xbits);
2657 if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits);
2658 }
2659 if (overflow == 0) return;
2660
2661 Trace((stderr,"\nbit length overflow\n"));
2662 /* This happens for example on obj2 and pic of the Calgary corpus */
2663
2664 /* Find the first bit length which could increase: */
2665 do {
2666 bits = max_length-1;
2667 while (s->bl_count[bits] == 0) bits--;
2668 s->bl_count[bits]--; /* move one leaf down the tree */
2669 s->bl_count[bits+1] += 2; /* move one overflow item as its brother */
2670 s->bl_count[max_length]--;
2671 /* The brother of the overflow item also moves one step up,
2672 * but this does not affect bl_count[max_length]
2673 */
2674 overflow -= 2;
2675 } while (overflow > 0);
2676
2677 /* Now recompute all bit lengths, scanning in increasing frequency.
2678 * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
2679 * lengths instead of fixing only the wrong ones. This idea is taken
2680 * from 'ar' written by Haruhiko Okumura.)
2681 */
2682 for (bits = max_length; bits != 0; bits--) {
2683 n = s->bl_count[bits];
2684 while (n != 0) {
2685 m = s->heap[--h];
2686 if (m > max_code) continue;
2687 if (tree[m].Len != (unsigned) bits) {
2688 Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits));
2689 s->opt_len += ((long)bits - (long)tree[m].Len)
2690 *(long)tree[m].Freq;
2691 tree[m].Len = (ush)bits;
2692 }
2693 n--;
2694 }
2695 }
2696 }
2697
2698 /* ===========================================================================
2699 * Generate the codes for a given tree and bit counts (which need not be
2700 * optimal).
2701 * IN assertion: the array bl_count contains the bit length statistics for
2702 * the given tree and the field len is set for all tree elements.
2703 * OUT assertion: the field code is set for all tree elements of non
2704 * zero code length.
2705 */
2706 local void gen_codes (tree, max_code, bl_count)
2707 ct_data *tree; /* the tree to decorate */
2708 int max_code; /* largest code with non zero frequency */
2709 ushf *bl_count; /* number of codes at each bit length */
2710 {
2711 ush next_code[MAX_BITS+1]; /* next code value for each bit length */
2712 ush code = 0; /* running code value */
2713 int bits; /* bit index */
2714 int n; /* code index */
2715
2716 /* The distribution counts are first used to generate the code values
2717 * without bit reversal.
2718 */
2719 for (bits = 1; bits <= MAX_BITS; bits++) {
2720 next_code[bits] = code = (code + bl_count[bits-1]) << 1;
2721 }
2722 /* Check that the bit counts in bl_count are consistent. The last code
2723 * must be all ones.
2724 */
2725 Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1,
2726 "inconsistent bit counts");
2727 Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
2728
2729 for (n = 0; n <= max_code; n++) {
2730 int len = tree[n].Len;
2731 if (len == 0) continue;
2732 /* Now reverse the bits */
2733 tree[n].Code = bi_reverse(next_code[len]++, len);
2734
2735 Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
2736 n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1));
2737 }
2738 }
2739
2740 /* ===========================================================================
2741 * Construct one Huffman tree and assigns the code bit strings and lengths.
2742 * Update the total bit length for the current block.
2743 * IN assertion: the field freq is set for all tree elements.
2744 * OUT assertions: the fields len and code are set to the optimal bit length
2745 * and corresponding code. The length opt_len is updated; static_len is
2746 * also updated if stree is not null. The field max_code is set.
2747 */
2748 local void build_tree(s, desc)
2749 deflate_state *s;
2750 tree_desc *desc; /* the tree descriptor */
2751 {
2752 ct_data *tree = desc->dyn_tree;
2753 const ct_data *stree = desc->stat_desc->static_tree;
2754 int elems = desc->stat_desc->elems;
2755 int n, m; /* iterate over heap elements */
2756 int max_code = -1; /* largest code with non zero frequency */
2757 int node; /* new node being created */
2758
2759 /* Construct the initial heap, with least frequent element in
2760 * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
2761 * heap[0] is not used.
2762 */
2763 s->heap_len = 0, s->heap_max = HEAP_SIZE;
2764
2765 for (n = 0; n < elems; n++) {
2766 if (tree[n].Freq != 0) {
2767 s->heap[++(s->heap_len)] = max_code = n;
2768 s->depth[n] = 0;
2769 } else {
2770 tree[n].Len = 0;
2771 }
2772 }
2773
2774 /* The pkzip format requires that at least one distance code exists,
2775 * and that at least one bit should be sent even if there is only one
2776 * possible code. So to avoid special checks later on we force at least
2777 * two codes of non zero frequency.
2778 */
2779 while (s->heap_len < 2) {
2780 node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0);
2781 tree[node].Freq = 1;
2782 s->depth[node] = 0;
2783 s->opt_len--; if (stree) s->static_len -= stree[node].Len;
2784 /* node is 0 or 1 so it does not have extra bits */
2785 }
2786 desc->max_code = max_code;
2787
2788 /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
2789 * establish sub-heaps of increasing lengths:
2790 */
2791 for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n);
2792
2793 /* Construct the Huffman tree by repeatedly combining the least two
2794 * frequent nodes.
2795 */
2796 node = elems; /* next internal node of the tree */
2797 do {
2798 pqremove(s, tree, n); /* n = node of least frequency */
2799 m = s->heap[SMALLEST]; /* m = node of next least frequency */
2800
2801 s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */
2802 s->heap[--(s->heap_max)] = m;
2803
2804 /* Create a new node father of n and m */
2805 tree[node].Freq = tree[n].Freq + tree[m].Freq;
2806 s->depth[node] = (uch) (MAX(s->depth[n], s->depth[m]) + 1);
2807 tree[n].Dad = tree[m].Dad = (ush)node;
2808 #ifdef DUMP_BL_TREE
2809 if (tree == s->bl_tree) {
2810 fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)",
2811 node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq);
2812 }
2813 #endif
2814 /* and insert the new node in the heap */
2815 s->heap[SMALLEST] = node++;
2816 pqdownheap(s, tree, SMALLEST);
2817
2818 } while (s->heap_len >= 2);
2819
2820 s->heap[--(s->heap_max)] = s->heap[SMALLEST];
2821
2822 /* At this point, the fields freq and dad are set. We can now
2823 * generate the bit lengths.
2824 */
2825 gen_bitlen(s, (tree_desc *)desc);
2826
2827 /* The field len is now set, we can generate the bit codes */
2828 gen_codes ((ct_data *)tree, max_code, s->bl_count);
2829 }
2830
2831 /* ===========================================================================
2832 * Scan a literal or distance tree to determine the frequencies of the codes
2833 * in the bit length tree.
2834 */
2835 local void scan_tree (s, tree, max_code)
2836 deflate_state *s;
2837 ct_data *tree; /* the tree to be scanned */
2838 int max_code; /* and its largest code of non zero frequency */
2839 {
2840 int n; /* iterates over all tree elements */
2841 int prevlen = -1; /* last emitted length */
2842 int curlen; /* length of current code */
2843 int nextlen = tree[0].Len; /* length of next code */
2844 int count = 0; /* repeat count of the current code */
2845 int max_count = 7; /* max repeat count */
2846 int min_count = 4; /* min repeat count */
2847
2848 if (nextlen == 0) max_count = 138, min_count = 3;
2849 tree[max_code+1].Len = (ush)0xffff; /* guard */
2850
2851 for (n = 0; n <= max_code; n++) {
2852 curlen = nextlen; nextlen = tree[n+1].Len;
2853 if (++count < max_count && curlen == nextlen) {
2854 continue;
2855 } else if (count < min_count) {
2856 s->bl_tree[curlen].Freq += count;
2857 } else if (curlen != 0) {
2858 if (curlen != prevlen) s->bl_tree[curlen].Freq++;
2859 s->bl_tree[REP_3_6].Freq++;
2860 } else if (count <= 10) {
2861 s->bl_tree[REPZ_3_10].Freq++;
2862 } else {
2863 s->bl_tree[REPZ_11_138].Freq++;
2864 }
2865 count = 0; prevlen = curlen;
2866 if (nextlen == 0) {
2867 max_count = 138, min_count = 3;
2868 } else if (curlen == nextlen) {
2869 max_count = 6, min_count = 3;
2870 } else {
2871 max_count = 7, min_count = 4;
2872 }
2873 }
2874 }
2875
2876 /* ===========================================================================
2877 * Send a literal or distance tree in compressed form, using the codes in
2878 * bl_tree.
2879 */
2880 local void send_tree (s, tree, max_code)
2881 deflate_state *s;
2882 ct_data *tree; /* the tree to be scanned */
2883 int max_code; /* and its largest code of non zero frequency */
2884 {
2885 int n; /* iterates over all tree elements */
2886 int prevlen = -1; /* last emitted length */
2887 int curlen; /* length of current code */
2888 int nextlen = tree[0].Len; /* length of next code */
2889 int count = 0; /* repeat count of the current code */
2890 int max_count = 7; /* max repeat count */
2891 int min_count = 4; /* min repeat count */
2892
2893 /* tree[max_code+1].Len = -1; */ /* guard already set */
2894 if (nextlen == 0) max_count = 138, min_count = 3;
2895
2896 for (n = 0; n <= max_code; n++) {
2897 curlen = nextlen; nextlen = tree[n+1].Len;
2898 if (++count < max_count && curlen == nextlen) {
2899 continue;
2900 } else if (count < min_count) {
2901 do { send_code(s, curlen, s->bl_tree); } while (--count != 0);
2902
2903 } else if (curlen != 0) {
2904 if (curlen != prevlen) {
2905 send_code(s, curlen, s->bl_tree); count--;
2906 }
2907 Assert(count >= 3 && count <= 6, " 3_6?");
2908 send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2);
2909
2910 } else if (count <= 10) {
2911 send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3);
2912
2913 } else {
2914 send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7);
2915 }
2916 count = 0; prevlen = curlen;
2917 if (nextlen == 0) {
2918 max_count = 138, min_count = 3;
2919 } else if (curlen == nextlen) {
2920 max_count = 6, min_count = 3;
2921 } else {
2922 max_count = 7, min_count = 4;
2923 }
2924 }
2925 }
2926
2927 /* ===========================================================================
2928 * Construct the Huffman tree for the bit lengths and return the index in
2929 * bl_order of the last bit length code to send.
2930 */
2931 local int build_bl_tree(s)
2932 deflate_state *s;
2933 {
2934 int max_blindex; /* index of last bit length code of non zero freq */
2935
2936 /* Determine the bit length frequencies for literal and distance trees */
2937 scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code);
2938 scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code);
2939
2940 /* Build the bit length tree: */
2941 build_tree(s, (tree_desc *)(&(s->bl_desc)));
2942 /* opt_len now includes the length of the tree representations, except
2943 * the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
2944 */
2945
2946 /* Determine the number of bit length codes to send. The pkzip format
2947 * requires that at least 4 bit length codes be sent. (appnote.txt says
2948 * 3 but the actual value used is 4.)
2949 */
2950 for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) {
2951 if (s->bl_tree[bl_order[max_blindex]].Len != 0) break;
2952 }
2953 /* Update opt_len to include the bit length tree and counts */
2954 s->opt_len += 3*(max_blindex+1) + 5+5+4;
2955 Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld",
2956 s->opt_len, s->static_len));
2957
2958 return max_blindex;
2959 }
2960
2961 /* ===========================================================================
2962 * Send the header for a block using dynamic Huffman trees: the counts, the
2963 * lengths of the bit length codes, the literal tree and the distance tree.
2964 * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
2965 */
2966 local void send_all_trees(s, lcodes, dcodes, blcodes)
2967 deflate_state *s;
2968 int lcodes, dcodes, blcodes; /* number of codes for each tree */
2969 {
2970 int rank; /* index in bl_order */
2971
2972 Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
2973 Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
2974 "too many codes");
2975 Tracev((stderr, "\nbl counts: "));
2976 send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */
2977 send_bits(s, dcodes-1, 5);
2978 send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */
2979 for (rank = 0; rank < blcodes; rank++) {
2980 Tracev((stderr, "\nbl code %2d ", bl_order[rank]));
2981 send_bits(s, s->bl_tree[bl_order[rank]].Len, 3);
2982 }
2983 Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent));
2984
2985 send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */
2986 Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent));
2987
2988 send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */
2989 Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent));
2990 }
2991
2992 /* ===========================================================================
2993 * Send a stored block
2994 */
2995 void _tr_stored_block(s, buf, stored_len, eof)
2996 deflate_state *s;
2997 charf *buf; /* input block */
2998 ulg stored_len; /* length of input block */
2999 int eof; /* true if this is the last block for a file */
3000 {
3001 send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */
3002 #ifdef DEBUG_ZLIB
3003 s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L;
3004 s->compressed_len += (stored_len + 4) << 3;
3005 #endif
3006 copy_block(s, buf, (unsigned)stored_len, 1); /* with header */
3007 }
3008
3009 /* ===========================================================================
3010 * Send one empty static block to give enough lookahead for inflate.
3011 * This takes 10 bits, of which 7 may remain in the bit buffer.
3012 * The current inflate code requires 9 bits of lookahead. If the
3013 * last two codes for the previous block (real code plus EOB) were coded
3014 * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode
3015 * the last real code. In this case we send two empty static blocks instead
3016 * of one. (There are no problems if the previous block is stored or fixed.)
3017 * To simplify the code, we assume the worst case of last real code encoded
3018 * on one bit only.
3019 */
3020 void _tr_align(s)
3021 deflate_state *s;
3022 {
3023 send_bits(s, STATIC_TREES<<1, 3);
3024 send_code(s, END_BLOCK, static_ltree);
3025 #ifdef DEBUG_ZLIB
3026 s->compressed_len += 10L; /* 3 for block type, 7 for EOB */
3027 #endif
3028 bi_flush(s);
3029 /* Of the 10 bits for the empty block, we have already sent
3030 * (10 - bi_valid) bits. The lookahead for the last real code (before
3031 * the EOB of the previous block) was thus at least one plus the length
3032 * of the EOB plus what we have just sent of the empty static block.
3033 */
3034 if (1 + s->last_eob_len + 10 - s->bi_valid < 9) {
3035 send_bits(s, STATIC_TREES<<1, 3);
3036 send_code(s, END_BLOCK, static_ltree);
3037 #ifdef DEBUG_ZLIB
3038 s->compressed_len += 10L;
3039 #endif
3040 bi_flush(s);
3041 }
3042 s->last_eob_len = 7;
3043 }
3044
3045 /* ===========================================================================
3046 * Determine the best encoding for the current block: dynamic trees, static
3047 * trees or store, and output the encoded block to the zip file.
3048 */
3049 void _tr_flush_block(s, buf, stored_len, eof)
3050 deflate_state *s;
3051 charf *buf; /* input block, or NULL if too old */
3052 ulg stored_len; /* length of input block */
3053 int eof; /* true if this is the last block for a file */
3054 {
3055 ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
3056 int max_blindex = 0; /* index of last bit length code of non zero freq */
3057
3058 /* Build the Huffman trees unless a stored block is forced */
3059 if (s->level > 0) {
3060
3061 /* Check if the file is ascii or binary */
3062 if (s->data_type == Z_UNKNOWN) set_data_type(s);
3063
3064 /* Construct the literal and distance trees */
3065 build_tree(s, (tree_desc *)(&(s->l_desc)));
3066 Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len,
3067 s->static_len));
3068
3069 build_tree(s, (tree_desc *)(&(s->d_desc)));
3070 Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len,
3071 s->static_len));
3072 /* At this point, opt_len and static_len are the total bit lengths of
3073 * the compressed block data, excluding the tree representations.
3074 */
3075
3076 /* Build the bit length tree for the above two trees, and get the index
3077 * in bl_order of the last bit length code to send.
3078 */
3079 max_blindex = build_bl_tree(s);
3080
3081 /* Determine the best encoding. Compute first the block length in bytes*/
3082 opt_lenb = (s->opt_len+3+7)>>3;
3083 static_lenb = (s->static_len+3+7)>>3;
3084
3085 Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
3086 opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
3087 s->last_lit));
3088
3089 if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
3090
3091 } else {
3092 Assert(buf != (char*)0, "lost buf");
3093 opt_lenb = static_lenb = stored_len + 5; /* force a stored block */
3094 }
3095
3096 #ifdef FORCE_STORED
3097 if (buf != (char*)0) { /* force stored block */
3098 #else
3099 if (stored_len+4 <= opt_lenb && buf != (char*)0) {
3100 /* 4: two words for the lengths */
3101 #endif
3102 /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
3103 * Otherwise we can't have processed more than WSIZE input bytes since
3104 * the last block flush, because compression would have been
3105 * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
3106 * transform a block into a stored block.
3107 */
3108 _tr_stored_block(s, buf, stored_len, eof);
3109
3110 #ifdef FORCE_STATIC
3111 } else if (static_lenb >= 0) { /* force static trees */
3112 #else
3113 } else if (static_lenb == opt_lenb) {
3114 #endif
3115 send_bits(s, (STATIC_TREES<<1)+eof, 3);
3116 compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree);
3117 #ifdef DEBUG_ZLIB
3118 s->compressed_len += 3 + s->static_len;
3119 #endif
3120 } else {
3121 send_bits(s, (DYN_TREES<<1)+eof, 3);
3122 send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1,
3123 max_blindex+1);
3124 compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree);
3125 #ifdef DEBUG_ZLIB
3126 s->compressed_len += 3 + s->opt_len;
3127 #endif
3128 }
3129 Assert (s->compressed_len == s->bits_sent, "bad compressed size");
3130 /* The above check is made mod 2^32, for files larger than 512 MB
3131 * and uLong implemented on 32 bits.
3132 */
3133 init_block(s);
3134
3135 if (eof) {
3136 bi_windup(s);
3137 #ifdef DEBUG_ZLIB
3138 s->compressed_len += 7; /* align on byte boundary */
3139 #endif
3140 }
3141 Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3,
3142 s->compressed_len-7*eof));
3143 }
3144
3145 /* ===========================================================================
3146 * Save the match info and tally the frequency counts. Return true if
3147 * the current block must be flushed.
3148 */
3149 int _tr_tally (s, dist, lc)
3150 deflate_state *s;
3151 unsigned dist; /* distance of matched string */
3152 unsigned lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */
3153 {
3154 s->d_buf[s->last_lit] = (ush)dist;
3155 s->l_buf[s->last_lit++] = (uch)lc;
3156 if (dist == 0) {
3157 /* lc is the unmatched char */
3158 s->dyn_ltree[lc].Freq++;
3159 } else {
3160 s->matches++;
3161 /* Here, lc is the match length - MIN_MATCH */
3162 dist--; /* dist = match distance - 1 */
3163 Assert((ush)dist < (ush)MAX_DIST(s) &&
3164 (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
3165 (ush)d_code(dist) < (ush)D_CODES, "_tr_tally: bad match");
3166
3167 s->dyn_ltree[_length_code[lc]+LITERALS+1].Freq++;
3168 s->dyn_dtree[d_code(dist)].Freq++;
3169 }
3170
3171 #ifdef TRUNCATE_BLOCK
3172 /* Try to guess if it is profitable to stop the current block here */
3173 if ((s->last_lit & 0x1fff) == 0 && s->level > 2) {
3174 /* Compute an upper bound for the compressed length */
3175 ulg out_length = (ulg)s->last_lit*8L;
3176 ulg in_length = (ulg)((long)s->strstart - s->block_start);
3177 int dcode;
3178 for (dcode = 0; dcode < D_CODES; dcode++) {
3179 out_length += (ulg)s->dyn_dtree[dcode].Freq *
3180 (5L+extra_dbits[dcode]);
3181 }
3182 out_length >>= 3;
3183 Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ",
3184 s->last_lit, in_length, out_length,
3185 100L - out_length*100L/in_length));
3186 if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1;
3187 }
3188 #endif
3189 return (s->last_lit == s->lit_bufsize-1);
3190 /* We avoid equality with lit_bufsize because of wraparound at 64K
3191 * on 16 bit machines and because stored blocks are restricted to
3192 * 64K-1 bytes.
3193 */
3194 }
3195
3196 /* ===========================================================================
3197 * Send the block data compressed using the given Huffman trees
3198 */
3199 local void compress_block(s, ltree, dtree)
3200 deflate_state *s;
3201 ct_data *ltree; /* literal tree */
3202 ct_data *dtree; /* distance tree */
3203 {
3204 unsigned dist; /* distance of matched string */
3205 int lc; /* match length or unmatched char (if dist == 0) */
3206 unsigned lx = 0; /* running index in l_buf */
3207 unsigned code; /* the code to send */
3208 int extra; /* number of extra bits to send */
3209
3210 if (s->last_lit != 0) do {
3211 dist = s->d_buf[lx];
3212 lc = s->l_buf[lx++];
3213 if (dist == 0) {
3214 send_code(s, lc, ltree); /* send a literal byte */
3215 Tracecv(isgraph(lc), (stderr," '%c' ", lc));
3216 } else {
3217 /* Here, lc is the match length - MIN_MATCH */
3218 code = _length_code[lc];
3219 send_code(s, code+LITERALS+1, ltree); /* send the length code */
3220 extra = extra_lbits[code];
3221 if (extra != 0) {
3222 lc -= base_length[code];
3223 send_bits(s, lc, extra); /* send the extra length bits */
3224 }
3225 dist--; /* dist is now the match distance - 1 */
3226 code = d_code(dist);
3227 Assert (code < D_CODES, "bad d_code");
3228
3229 send_code(s, code, dtree); /* send the distance code */
3230 extra = extra_dbits[code];
3231 if (extra != 0) {
3232 dist -= base_dist[code];
3233 send_bits(s, dist, extra); /* send the extra distance bits */
3234 }
3235 } /* literal or match pair ? */
3236
3237 /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */
3238 Assert(s->pending < s->lit_bufsize + 2*lx, "pendingBuf overflow");
3239
3240 } while (lx < s->last_lit);
3241
3242 send_code(s, END_BLOCK, ltree);
3243 s->last_eob_len = ltree[END_BLOCK].Len;
3244 }
3245
3246 /* ===========================================================================
3247 * Set the data type to ASCII or BINARY, using a crude approximation:
3248 * binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise.
3249 * IN assertion: the fields freq of dyn_ltree are set and the total of all
3250 * frequencies does not exceed 64K (to fit in an int on 16 bit machines).
3251 */
3252 local void set_data_type(s)
3253 deflate_state *s;
3254 {
3255 int n = 0;
3256 unsigned ascii_freq = 0;
3257 unsigned bin_freq = 0;
3258 while (n < 7) bin_freq += s->dyn_ltree[n++].Freq;
3259 while (n < 128) ascii_freq += s->dyn_ltree[n++].Freq;
3260 while (n < LITERALS) bin_freq += s->dyn_ltree[n++].Freq;
3261 s->data_type = (Byte)(bin_freq > (ascii_freq >> 2) ? Z_BINARY : Z_ASCII);
3262 }
3263
3264 /* ===========================================================================
3265 * Reverse the first len bits of a code, using straightforward code (a faster
3266 * method would use a table)
3267 * IN assertion: 1 <= len <= 15
3268 */
3269 local unsigned bi_reverse(code, len)
3270 unsigned code; /* the value to invert */
3271 int len; /* its bit length */
3272 {
3273 register unsigned res = 0;
3274 do {
3275 res |= code & 1;
3276 code >>= 1, res <<= 1;
3277 } while (--len > 0);
3278 return res >> 1;
3279 }
3280
3281 /* ===========================================================================
3282 * Flush the bit buffer, keeping at most 7 bits in it.
3283 */
3284 local void bi_flush(s)
3285 deflate_state *s;
3286 {
3287 if (s->bi_valid == 16) {
3288 put_short(s, s->bi_buf);
3289 s->bi_buf = 0;
3290 s->bi_valid = 0;
3291 } else if (s->bi_valid >= 8) {
3292 put_byte(s, (Byte)s->bi_buf);
3293 s->bi_buf >>= 8;
3294 s->bi_valid -= 8;
3295 }
3296 }
3297
3298 /* ===========================================================================
3299 * Flush the bit buffer and align the output on a byte boundary
3300 */
3301 local void bi_windup(s)
3302 deflate_state *s;
3303 {
3304 if (s->bi_valid > 8) {
3305 put_short(s, s->bi_buf);
3306 } else if (s->bi_valid > 0) {
3307 put_byte(s, (Byte)s->bi_buf);
3308 }
3309 s->bi_buf = 0;
3310 s->bi_valid = 0;
3311 #ifdef DEBUG_ZLIB
3312 s->bits_sent = (s->bits_sent+7) & ~7;
3313 #endif
3314 }
3315
3316 /* ===========================================================================
3317 * Copy a stored block, storing first the length and its
3318 * one's complement if requested.
3319 */
3320 local void copy_block(s, buf, len, header)
3321 deflate_state *s;
3322 charf *buf; /* the input data */
3323 unsigned len; /* its length */
3324 int header; /* true if block header must be written */
3325 {
3326 bi_windup(s); /* align on byte boundary */
3327 s->last_eob_len = 8; /* enough lookahead for inflate */
3328
3329 if (header) {
3330 put_short(s, (ush)len);
3331 put_short(s, (ush)~len);
3332 #ifdef DEBUG_ZLIB
3333 s->bits_sent += 2*16;
3334 #endif
3335 }
3336 #ifdef DEBUG_ZLIB
3337 s->bits_sent += (ulg)len<<3;
3338 #endif
3339 while (len--) {
3340 put_byte(s, *buf++);
3341 }
3342 }
3343 /* --- trees.c */
3344
3345 /* +++ inflate.c */
3346 /* inflate.c -- zlib interface to inflate modules
3347 * Copyright (C) 1995-2002 Mark Adler
3348 * For conditions of distribution and use, see copyright notice in zlib.h
3349 */
3350
3351 /* #include "zutil.h" */
3352
3353 /* +++ infblock.h */
3354 /* infblock.h -- header to use infblock.c
3355 * Copyright (C) 1995-2002 Mark Adler
3356 * For conditions of distribution and use, see copyright notice in zlib.h
3357 */
3358
3359 /* WARNING: this file should *not* be used by applications. It is
3360 part of the implementation of the compression library and is
3361 subject to change. Applications should only use zlib.h.
3362 */
3363
3364 struct inflate_blocks_state;
3365 typedef struct inflate_blocks_state FAR inflate_blocks_statef;
3366
3367 extern inflate_blocks_statef * inflate_blocks_new OF((
3368 z_streamp z,
3369 check_func c, /* check function */
3370 uInt w)); /* window size */
3371
3372 extern int inflate_blocks OF((
3373 inflate_blocks_statef *,
3374 z_streamp ,
3375 int)); /* initial return code */
3376
3377 extern void inflate_blocks_reset OF((
3378 inflate_blocks_statef *,
3379 z_streamp ,
3380 uLongf *)); /* check value on output */
3381
3382 extern int inflate_blocks_free OF((
3383 inflate_blocks_statef *,
3384 z_streamp));
3385
3386 extern void inflate_set_dictionary OF((
3387 inflate_blocks_statef *s,
3388 const Bytef *d, /* dictionary */
3389 uInt n)); /* dictionary length */
3390
3391 extern int inflate_blocks_sync_point OF((
3392 inflate_blocks_statef *s));
3393 /* --- infblock.h */
3394
3395 #ifndef NO_DUMMY_DECL
3396 struct inflate_blocks_state {int dummy;}; /* for buggy compilers */
3397 #endif
3398
3399 /* inflate private state */
3400 typedef struct inflate_state {
3401
3402 /* mode */
3403 enum {
3404 METHOD, /* waiting for method byte */
3405 FLAG, /* waiting for flag byte */
3406 DICT4, /* four dictionary check bytes to go */
3407 DICT3, /* three dictionary check bytes to go */
3408 DICT2, /* two dictionary check bytes to go */
3409 DICT1, /* one dictionary check byte to go */
3410 DICT0, /* waiting for inflateSetDictionary */
3411 BLOCKS, /* decompressing blocks */
3412 CHECK4, /* four check bytes to go */
3413 CHECK3, /* three check bytes to go */
3414 CHECK2, /* two check bytes to go */
3415 CHECK1, /* one check byte to go */
3416 DONE, /* finished check, done */
3417 BAD} /* got an error--stay here */
3418 mode; /* current inflate mode */
3419
3420 /* mode dependent information */
3421 union {
3422 uInt method; /* if FLAGS, method byte */
3423 struct {
3424 uLong was; /* computed check value */
3425 uLong need; /* stream check value */
3426 } check; /* if CHECK, check values to compare */
3427 uInt marker; /* if BAD, inflateSync's marker bytes count */
3428 } sub; /* submode */
3429
3430 /* mode independent information */
3431 int nowrap; /* flag for no wrapper */
3432 uInt wbits; /* log2(window size) (8..15, defaults to 15) */
3433 inflate_blocks_statef
3434 *blocks; /* current inflate_blocks state */
3435
3436 }inflate_state;
3437
3438
3439 int ZEXPORT inflateReset(z)
3440 z_streamp z;
3441 {
3442 inflate_state* s;
3443 if (z == Z_NULL || z->state == Z_NULL)
3444 return Z_STREAM_ERROR;
3445
3446 s = (inflate_state*)z->state;
3447 z->total_in = z->total_out = 0;
3448 z->msg = Z_NULL;
3449 s->mode = s->nowrap ? BLOCKS : METHOD;
3450 inflate_blocks_reset(s->blocks, z, Z_NULL);
3451 Tracev((stderr, "inflate: reset\n"));
3452 return Z_OK;
3453 }
3454
3455
3456 int ZEXPORT inflateEnd(z)
3457 z_streamp z;
3458 {
3459 if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL)
3460 return Z_STREAM_ERROR;
3461 if (((inflate_state*)z->state)->blocks != Z_NULL)
3462 inflate_blocks_free(((inflate_state*)z->state)->blocks, z);
3463 ZFREE(z, z->state);
3464 z->state = Z_NULL;
3465 Tracev((stderr, "inflate: end\n"));
3466 return Z_OK;
3467 }
3468
3469
3470 int ZEXPORT inflateInit2_(z, w, version, stream_size)
3471 z_streamp z;
3472 int w;
3473 const char *version;
3474 int stream_size;
3475 {
3476 inflate_state* s;
3477 if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
3478 stream_size != sizeof(z_stream))
3479 return Z_VERSION_ERROR;
3480
3481 /* initialize state */
3482 if (z == Z_NULL)
3483 return Z_STREAM_ERROR;
3484 z->msg = Z_NULL;
3485 #ifndef NO_ZCFUNCS
3486 if (z->zalloc == Z_NULL)
3487 {
3488 z->zalloc = zcalloc;
3489 z->opaque = (voidpf)0;
3490 }
3491 if (z->zfree == Z_NULL) z->zfree = zcfree;
3492 #endif
3493 if ((z->state = (struct internal_state FAR *)
3494 ZALLOC(z,1,sizeof(struct inflate_state))) == Z_NULL)
3495 return Z_MEM_ERROR;
3496 s = (inflate_state*)z->state;
3497 s->blocks = Z_NULL;
3498
3499 /* handle undocumented nowrap option (no zlib header or check) */
3500 s->nowrap = 0;
3501 if (w < 0)
3502 {
3503 w = - w;
3504 s->nowrap = 1;
3505 }
3506
3507 /* set window size */
3508 if (w < 8 || w > 15)
3509 {
3510 inflateEnd(z);
3511 return Z_STREAM_ERROR;
3512 }
3513 s->wbits = (uInt)w;
3514
3515 /* create inflate_blocks state */
3516 if ((s->blocks =
3517 inflate_blocks_new(z, s->nowrap ? Z_NULL : adler32, (uInt)1 << w))
3518 == Z_NULL)
3519 {
3520 inflateEnd(z);
3521 return Z_MEM_ERROR;
3522 }
3523 Tracev((stderr, "inflate: allocated\n"));
3524
3525 /* reset state */
3526 inflateReset(z);
3527 return Z_OK;
3528 }
3529
3530
3531 int ZEXPORT inflateInit_(z, version, stream_size)
3532 z_streamp z;
3533 const char *version;
3534 int stream_size;
3535 {
3536 return inflateInit2_(z, DEF_WBITS, version, stream_size);
3537 }
3538
3539
3540 #define NEEDBYTE {if(z->avail_in==0)return r;r=f;}
3541 #define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++)
3542
3543 int ZEXPORT inflate(z, f)
3544 z_streamp z;
3545 int f;
3546 {
3547 int r;
3548 uInt b;
3549 inflate_state* s;
3550
3551 if (z == Z_NULL || z->state == Z_NULL || z->next_in == Z_NULL)
3552 return Z_STREAM_ERROR;
3553 f = f == Z_FINISH ? Z_BUF_ERROR : Z_OK;
3554 r = Z_BUF_ERROR;
3555 s = (inflate_state*)z->state;
3556 while (1) switch (s->mode)
3557 {
3558 case METHOD:
3559 NEEDBYTE
3560 if (((s->sub.method = NEXTBYTE) & 0xf) != Z_DEFLATED)
3561 {
3562 s->mode = BAD;
3563 z->msg = (char*)"unknown compression method";
3564 s->sub.marker = 5; /* can't try inflateSync */
3565 break;
3566 }
3567 if ((s->sub.method >> 4) + 8 > s->wbits)
3568 {
3569 s->mode = BAD;
3570 z->msg = (char*)"invalid window size";
3571 s->sub.marker = 5; /* can't try inflateSync */
3572 break;
3573 }
3574 s->mode = FLAG;
3575 case FLAG:
3576 NEEDBYTE
3577 b = NEXTBYTE;
3578 if (((s->sub.method << 8) + b) % 31)
3579 {
3580 s->mode = BAD;
3581 z->msg = (char*)"incorrect header check";
3582 s->sub.marker = 5; /* can't try inflateSync */
3583 break;
3584 }
3585 Tracev((stderr, "inflate: zlib header ok\n"));
3586 if (!(b & PRESET_DICT))
3587 {
3588 s->mode = BLOCKS;
3589 break;
3590 }
3591 s->mode = DICT4;
3592 case DICT4:
3593 NEEDBYTE
3594 s->sub.check.need = (uLong)NEXTBYTE << 24;
3595 s->mode = DICT3;
3596 case DICT3:
3597 NEEDBYTE
3598 s->sub.check.need += (uLong)NEXTBYTE << 16;
3599 s->mode = DICT2;
3600 case DICT2:
3601 NEEDBYTE
3602 s->sub.check.need += (uLong)NEXTBYTE << 8;
3603 s->mode = DICT1;
3604 case DICT1:
3605 NEEDBYTE
3606 s->sub.check.need += (uLong)NEXTBYTE;
3607 z->adler = s->sub.check.need;
3608 s->mode = DICT0;
3609 return Z_NEED_DICT;
3610 case DICT0:
3611 s->mode = BAD;
3612 z->msg = (char*)"need dictionary";
3613 s->sub.marker = 0; /* can try inflateSync */
3614 return Z_STREAM_ERROR;
3615 case BLOCKS:
3616 r = inflate_blocks(s->blocks, z, r);
3617 if (r == Z_DATA_ERROR)
3618 {
3619 s->mode = BAD;
3620 s->sub.marker = 0; /* can try inflateSync */
3621 break;
3622 }
3623 if (r == Z_OK)
3624 r = f;
3625 if (r != Z_STREAM_END)
3626 return r;
3627 r = f;
3628 inflate_blocks_reset(s->blocks, z, &s->sub.check.was);
3629 if (s->nowrap)
3630 {
3631 s->mode = DONE;
3632 break;
3633 }
3634 s->mode = CHECK4;
3635 case CHECK4:
3636 NEEDBYTE
3637 s->sub.check.need = (uLong)NEXTBYTE << 24;
3638 s->mode = CHECK3;
3639 case CHECK3:
3640 NEEDBYTE
3641 s->sub.check.need += (uLong)NEXTBYTE << 16;
3642 s->mode = CHECK2;
3643 case CHECK2:
3644 NEEDBYTE
3645 s->sub.check.need += (uLong)NEXTBYTE << 8;
3646 s->mode = CHECK1;
3647 case CHECK1:
3648 NEEDBYTE
3649 s->sub.check.need += (uLong)NEXTBYTE;
3650
3651 if (s->sub.check.was != s->sub.check.need)
3652 {
3653 s->mode = BAD;
3654 z->msg = (char*)"incorrect data check";
3655 s->sub.marker = 5; /* can't try inflateSync */
3656 break;
3657 }
3658 Tracev((stderr, "inflate: zlib check ok\n"));
3659 s->mode = DONE;
3660 case DONE:
3661 return Z_STREAM_END;
3662 case BAD:
3663 return Z_DATA_ERROR;
3664 default:
3665 return Z_STREAM_ERROR;
3666 }
3667 #ifdef NEED_DUMMY_RETURN
3668 return Z_STREAM_ERROR; /* Some dumb compilers complain without this */
3669 #endif
3670 }
3671
3672
3673 int ZEXPORT inflateSetDictionary(z, dictionary, dictLength)
3674 z_streamp z;
3675 const Bytef *dictionary;
3676 uInt dictLength;
3677 {
3678 uInt length = dictLength;
3679 inflate_state* s;
3680
3681 if (z == Z_NULL || z->state == Z_NULL || ((inflate_state*)z->state)->mode != DICT0)
3682 return Z_STREAM_ERROR;
3683 s = (inflate_state*)z->state;
3684
3685 if (adler32(1L, dictionary, dictLength) != z->adler) return Z_DATA_ERROR;
3686 z->adler = 1L;
3687
3688 if (length >= ((uInt)1<<s->wbits))
3689 {
3690 length = (1<<s->wbits)-1;
3691 dictionary += dictLength - length;
3692 }
3693 inflate_set_dictionary(s->blocks, dictionary, length);
3694 s->mode = BLOCKS;
3695 return Z_OK;
3696 }
3697
3698
3699 int ZEXPORT inflateSync(z)
3700 z_streamp z;
3701 {
3702 uInt n; /* number of bytes to look at */
3703 Bytef *p; /* pointer to bytes */
3704 uInt m; /* number of marker bytes found in a row */
3705 uLong r, w; /* temporaries to save total_in and total_out */
3706 inflate_state* s;
3707
3708 /* set up */
3709 if (z == Z_NULL || z->state == Z_NULL)
3710 return Z_STREAM_ERROR;
3711 s = (inflate_state*)z->state;
3712 if (s->mode != BAD)
3713 {
3714 s->mode = BAD;
3715 s->sub.marker = 0;
3716 }
3717 if ((n = z->avail_in) == 0)
3718 return Z_BUF_ERROR;
3719 p = z->next_in;
3720 m = s->sub.marker;
3721
3722 /* search */
3723 while (n && m < 4)
3724 {
3725 static const Byte mark[4] = {0, 0, 0xff, 0xff};
3726 if (*p == mark[m])
3727 m++;
3728 else if (*p)
3729 m = 0;
3730 else
3731 m = 4 - m;
3732 p++, n--;
3733 }
3734
3735 /* restore */
3736 z->total_in += p - z->next_in;
3737 z->next_in = p;
3738 z->avail_in = n;
3739 s->sub.marker = m;
3740
3741 /* return no joy or set up to restart on a new block */
3742 if (m != 4)
3743 return Z_DATA_ERROR;
3744 r = z->total_in; w = z->total_out;
3745 inflateReset(z);
3746 z->total_in = r; z->total_out = w;
3747 s->mode = BLOCKS;
3748 return Z_OK;
3749 }
3750
3751
3752 /* Returns true if inflate is currently at the end of a block generated
3753 * by Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
3754 * implementation to provide an additional safety check. PPP uses Z_SYNC_FLUSH
3755 * but removes the length bytes of the resulting empty stored block. When
3756 * decompressing, PPP checks that at the end of input packet, inflate is
3757 * waiting for these length bytes.
3758 */
3759 int ZEXPORT inflateSyncPoint(z)
3760 z_streamp z;
3761 {
3762 if (z == Z_NULL || z->state == Z_NULL || ((inflate_state*)z->state)->blocks == Z_NULL)
3763 return Z_STREAM_ERROR;
3764 return inflate_blocks_sync_point(((inflate_state*)z->state)->blocks);
3765 }
3766 #undef NEEDBYTE
3767 #undef NEXTBYTE
3768 /* --- inflate.c */
3769
3770 /* +++ infblock.c */
3771 /* infblock.c -- interpret and process block types to last block
3772 * Copyright (C) 1995-2002 Mark Adler
3773 * For conditions of distribution and use, see copyright notice in zlib.h
3774 */
3775
3776 /* #include "zutil.h" */
3777 /* #include "infblock.h" */
3778
3779 /* +++ inftrees.h */
3780 /* inftrees.h -- header to use inftrees.c
3781 * Copyright (C) 1995-2002 Mark Adler
3782 * For conditions of distribution and use, see copyright notice in zlib.h
3783 */
3784
3785 /* WARNING: this file should *not* be used by applications. It is
3786 part of the implementation of the compression library and is
3787 subject to change. Applications should only use zlib.h.
3788 */
3789
3790 /* Huffman code lookup table entry--this entry is four bytes for machines
3791 that have 16-bit pointers (e.g. PC's in the small or medium model). */
3792
3793 typedef struct inflate_huft_s FAR inflate_huft;
3794
3795 struct inflate_huft_s {
3796 union {
3797 struct {
3798 Byte Exop; /* number of extra bits or operation */
3799 Byte Bits; /* number of bits in this code or subcode */
3800 } what;
3801 uInt pad; /* pad structure to a power of 2 (4 bytes for */
3802 } word; /* 16-bit, 8 bytes for 32-bit int's) */
3803 uInt base; /* literal, length base, distance base,
3804 or table offset */
3805 };
3806
3807 /* Maximum size of dynamic tree. The maximum found in a long but non-
3808 exhaustive search was 1004 huft structures (850 for length/literals
3809 and 154 for distances, the latter actually the result of an
3810 exhaustive search). The actual maximum is not known, but the
3811 value below is more than safe. */
3812 #define MANY 1440
3813
3814 extern int inflate_trees_bits OF((
3815 uIntf *, /* 19 code lengths */
3816 uIntf *, /* bits tree desired/actual depth */
3817 inflate_huft * FAR *, /* bits tree result */
3818 inflate_huft *, /* space for trees */
3819 z_streamp)); /* for messages */
3820
3821 extern int inflate_trees_dynamic OF((
3822 uInt, /* number of literal/length codes */
3823 uInt, /* number of distance codes */
3824 uIntf *, /* that many (total) code lengths */
3825 uIntf *, /* literal desired/actual bit depth */
3826 uIntf *, /* distance desired/actual bit depth */
3827 inflate_huft * FAR *, /* literal/length tree result */
3828 inflate_huft * FAR *, /* distance tree result */
3829 inflate_huft *, /* space for trees */
3830 z_streamp)); /* for messages */
3831
3832 extern int inflate_trees_fixed OF((
3833 uIntf *, /* literal desired/actual bit depth */
3834 uIntf *, /* distance desired/actual bit depth */
3835 inflate_huft * FAR *, /* literal/length tree result */
3836 inflate_huft * FAR *, /* distance tree result */
3837 z_streamp)); /* for memory allocation */
3838 /* --- inftrees.h */
3839
3840 /* +++ infcodes.h */
3841 /* infcodes.h -- header to use infcodes.c
3842 * Copyright (C) 1995-2002 Mark Adler
3843 * For conditions of distribution and use, see copyright notice in zlib.h
3844 */
3845
3846 /* WARNING: this file should *not* be used by applications. It is
3847 part of the implementation of the compression library and is
3848 subject to change. Applications should only use zlib.h.
3849 */
3850
3851 struct inflate_codes_state;
3852 typedef struct inflate_codes_state FAR inflate_codes_statef;
3853
3854 extern inflate_codes_statef *inflate_codes_new OF((
3855 uInt, uInt,
3856 inflate_huft *, inflate_huft *,
3857 z_streamp ));
3858
3859 extern int inflate_codes OF((
3860 inflate_blocks_statef *,
3861 z_streamp ,
3862 int));
3863
3864 extern void inflate_codes_free OF((
3865 inflate_codes_statef *,
3866 z_streamp ));
3867
3868 /* --- infcodes.h */
3869
3870 /* +++ infutil.h */
3871 /* infutil.h -- types and macros common to blocks and codes
3872 * Copyright (C) 1995-2002 Mark Adler
3873 * For conditions of distribution and use, see copyright notice in zlib.h
3874 */
3875
3876 /* WARNING: this file should *not* be used by applications. It is
3877 part of the implementation of the compression library and is
3878 subject to change. Applications should only use zlib.h.
3879 */
3880
3881 #ifndef _INFUTIL_H
3882 #define _INFUTIL_H
3883
3884 typedef enum {
3885 TYPE, /* get type bits (3, including end bit) */
3886 LENS, /* get lengths for stored */
3887 STORED, /* processing stored block */
3888 TABLE, /* get table lengths */
3889 BTREE, /* get bit lengths tree for a dynamic block */
3890 DTREE, /* get length, distance trees for a dynamic block */
3891 CODES, /* processing fixed or dynamic block */
3892 DRY, /* output remaining window bytes */
3893 DONEB, /* finished last block, done */
3894 BADB} /* got a data error--stuck here */
3895 inflate_block_mode;
3896
3897 /* inflate blocks semi-private state */
3898 struct inflate_blocks_state {
3899
3900 /* mode */
3901 inflate_block_mode mode; /* current inflate_block mode */
3902
3903 /* mode dependent information */
3904 union {
3905 uInt left; /* if STORED, bytes left to copy */
3906 struct {
3907 uInt table; /* table lengths (14 bits) */
3908 uInt index; /* index into blens (or border) */
3909 uIntf *blens; /* bit lengths of codes */
3910 uInt bb; /* bit length tree depth */
3911 inflate_huft *tb; /* bit length decoding tree */
3912 } trees; /* if DTREE, decoding info for trees */
3913 struct {
3914 inflate_codes_statef
3915 *codes;
3916 } decode; /* if CODES, current state */
3917 } sub; /* submode */
3918 uInt last; /* true if this block is the last block */
3919
3920 /* mode independent information */
3921 uInt bitk; /* bits in bit buffer */
3922 uLong bitb; /* bit buffer */
3923 inflate_huft *hufts; /* single malloc for tree space */
3924 Bytef *window; /* sliding window */
3925 Bytef *end; /* one byte after sliding window */
3926 Bytef *read; /* window read pointer */
3927 Bytef *write; /* window write pointer */
3928 check_func checkfn; /* check function */
3929 uLong check; /* check on output */
3930
3931 };
3932
3933
3934 /* defines for inflate input/output */
3935 /* update pointers and return */
3936 #define UPDBITS {s->bitb=b;s->bitk=k;}
3937 #define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;}
3938 #define UPDOUT {s->write=q;}
3939 #define UPDATE {UPDBITS UPDIN UPDOUT}
3940 #define LEAVE {UPDATE return inflate_flush(s,z,r);}
3941 /* get bytes and bits */
3942 #define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;}
3943 #define NEEDBYTE {if(n)r=Z_OK;else LEAVE}
3944 #define NEXTBYTE (n--,*p++)
3945 #define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}}
3946 #define DUMPBITS(j) {b>>=(j);k-=(j);}
3947 /* output bytes */
3948 #define WAVAIL (uInt)(q<s->read?s->read-q-1:s->end-q)
3949 #define LOADOUT {q=s->write;m=(uInt)WAVAIL;}
3950 #define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}}
3951 #define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT}
3952 #define NEEDOUT {if(m==0){WRAP if(m==0){FLUSH WRAP if(m==0) LEAVE}}r=Z_OK;}
3953 #define OUTBYTE(a) {*q++=(Byte)(a);m--;}
3954 /* load local pointers */
3955 #define LOAD {LOADIN LOADOUT}
3956
3957 /* masks for lower bits (size given to avoid silly warnings with Visual C++) */
3958 extern uInt inflate_mask[17];
3959
3960 /* copy as much as possible from the sliding window to the output area */
3961 extern int inflate_flush OF((
3962 inflate_blocks_statef *,
3963 z_streamp ,
3964 int));
3965
3966 #ifndef NO_DUMMY_DECL
3967 struct internal_state {int dummy;}; /* for buggy compilers */
3968 #endif
3969
3970 #endif
3971 /* --- infutil.h */
3972
3973 #ifndef NO_DUMMY_DECL
3974 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
3975 #endif
3976
3977 /* simplify the use of the inflate_huft type with some defines */
3978 #define exop word.what.Exop
3979 #define bits word.what.Bits
3980
3981 /* Table for deflate from PKZIP's appnote.txt. */
3982 local const uInt border[] = { /* Order of the bit length code lengths */
3983 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
3984
3985 /*
3986 Notes beyond the 1.93a appnote.txt:
3987
3988 1. Distance pointers never point before the beginning of the output
3989 stream.
3990 2. Distance pointers can point back across blocks, up to 32k away.
3991 3. There is an implied maximum of 7 bits for the bit length table and
3992 15 bits for the actual data.
3993 4. If only one code exists, then it is encoded using one bit. (Zero
3994 would be more efficient, but perhaps a little confusing.) If two
3995 codes exist, they are coded using one bit each (0 and 1).
3996 5. There is no way of sending zero distance codes--a dummy must be
3997 sent if there are none. (History: a pre 2.0 version of PKZIP would
3998 store blocks with no distance codes, but this was discovered to be
3999 too harsh a criterion.) Valid only for 1.93a. 2.04c does allow
4000 zero distance codes, which is sent as one code of zero bits in
4001 length.
4002 6. There are up to 286 literal/length codes. Code 256 represents the
4003 end-of-block. Note however that the static length tree defines
4004 288 codes just to fill out the Huffman codes. Codes 286 and 287
4005 cannot be used though, since there is no length base or extra bits
4006 defined for them. Similarily, there are up to 30 distance codes.
4007 However, static trees define 32 codes (all 5 bits) to fill out the
4008 Huffman codes, but the last two had better not show up in the data.
4009 7. Unzip can check dynamic Huffman blocks for complete code sets.
4010 The exception is that a single code would not be complete (see #4).
4011 8. The five bits following the block type is really the number of
4012 literal codes sent minus 257.
4013 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
4014 (1+6+6). Therefore, to output three times the length, you output
4015 three codes (1+1+1), whereas to output four times the same length,
4016 you only need two codes (1+3). Hmm.
4017 10. In the tree reconstruction algorithm, Code = Code + Increment
4018 only if BitLength(i) is not zero. (Pretty obvious.)
4019 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19)
4020 12. Note: length code 284 can represent 227-258, but length code 285
4021 really is 258. The last length deserves its own, short code
4022 since it gets used a lot in very redundant files. The length
4023 258 is special since 258 - 3 (the min match length) is 255.
4024 13. The literal/length and distance code bit lengths are read as a
4025 single stream of lengths. It is possible (and advantageous) for
4026 a repeat code (16, 17, or 18) to go across the boundary between
4027 the two sets of lengths.
4028 */
4029
4030
4031 void inflate_blocks_reset(s, z, c)
4032 inflate_blocks_statef *s;
4033 z_streamp z;
4034 uLongf *c;
4035 {
4036 if (c != Z_NULL)
4037 *c = s->check;
4038 if (s->mode == BTREE || s->mode == DTREE)
4039 ZFREE(z, s->sub.trees.blens);
4040 if (s->mode == CODES)
4041 inflate_codes_free(s->sub.decode.codes, z);
4042 s->mode = TYPE;
4043 s->bitk = 0;
4044 s->bitb = 0;
4045 s->read = s->write = s->window;
4046 if (s->checkfn != Z_NULL)
4047 z->adler = s->check = (*s->checkfn)(0L, (const Bytef *)Z_NULL, 0);
4048 Tracev((stderr, "inflate: blocks reset\n"));
4049 }
4050
4051
4052 inflate_blocks_statef *inflate_blocks_new(z, c, w)
4053 z_streamp z;
4054 check_func c;
4055 uInt w;
4056 {
4057 inflate_blocks_statef *s;
4058
4059 if ((s = (inflate_blocks_statef *)ZALLOC
4060 (z,1,sizeof(struct inflate_blocks_state))) == Z_NULL)
4061 return s;
4062 if ((s->hufts =
4063 (inflate_huft *)ZALLOC(z, sizeof(inflate_huft), MANY)) == Z_NULL)
4064 {
4065 ZFREE(z, s);
4066 return Z_NULL;
4067 }
4068 if ((s->window = (Bytef *)ZALLOC(z, 1, w)) == Z_NULL)
4069 {
4070 ZFREE(z, s->hufts);
4071 ZFREE(z, s);
4072 return Z_NULL;
4073 }
4074 s->end = s->window + w;
4075 s->checkfn = c;
4076 s->mode = TYPE;
4077 Tracev((stderr, "inflate: blocks allocated\n"));
4078 inflate_blocks_reset(s, z, Z_NULL);
4079 return s;
4080 }
4081
4082
4083 int inflate_blocks(s, z, r)
4084 inflate_blocks_statef *s;
4085 z_streamp z;
4086 int r;
4087 {
4088 uInt t; /* temporary storage */
4089 uLong b; /* bit buffer */
4090 uInt k; /* bits in bit buffer */
4091 Bytef *p; /* input data pointer */
4092 uInt n; /* bytes available there */
4093 Bytef *q; /* output window write pointer */
4094 uInt m; /* bytes to end of window or read pointer */
4095
4096 /* copy input/output information to locals (UPDATE macro restores) */
4097 LOAD
4098
4099 /* process input based on current state */
4100 while (1) switch (s->mode)
4101 {
4102 case TYPE:
4103 NEEDBITS(3)
4104 t = (uInt)b & 7;
4105 s->last = t & 1;
4106 switch (t >> 1)
4107 {
4108 case 0: /* stored */
4109 Tracev((stderr, "inflate: stored block%s\n",
4110 s->last ? " (last)" : ""));
4111 DUMPBITS(3)
4112 t = k & 7; /* go to byte boundary */
4113 DUMPBITS(t)
4114 s->mode = LENS; /* get length of stored block */
4115 break;
4116 case 1: /* fixed */
4117 Tracev((stderr, "inflate: fixed codes block%s\n",
4118 s->last ? " (last)" : ""));
4119 {
4120 uInt bl, bd;
4121 inflate_huft *tl, *td;
4122
4123 inflate_trees_fixed(&bl, &bd, &tl, &td, z);
4124 s->sub.decode.codes = inflate_codes_new(bl, bd, tl, td, z);
4125 if (s->sub.decode.codes == Z_NULL)
4126 {
4127 r = Z_MEM_ERROR;
4128 LEAVE
4129 }
4130 }
4131 DUMPBITS(3)
4132 s->mode = CODES;
4133 break;
4134 case 2: /* dynamic */
4135 Tracev((stderr, "inflate: dynamic codes block%s\n",
4136 s->last ? " (last)" : ""));
4137 DUMPBITS(3)
4138 s->mode = TABLE;
4139 break;
4140 case 3: /* illegal */
4141 DUMPBITS(3)
4142 s->mode = BADB;
4143 z->msg = (char*)"invalid block type";
4144 r = Z_DATA_ERROR;
4145 LEAVE
4146 }
4147 break;
4148 case LENS:
4149 NEEDBITS(32)
4150 if ((((~b) >> 16) & 0xffff) != (b & 0xffff))
4151 {
4152 s->mode = BADB;
4153 z->msg = (char*)"invalid stored block lengths";
4154 r = Z_DATA_ERROR;
4155 LEAVE
4156 }
4157 s->sub.left = (uInt)b & 0xffff;
4158 b = k = 0; /* dump bits */
4159 Tracev((stderr, "inflate: stored length %u\n", s->sub.left));
4160 s->mode = s->sub.left ? STORED : (s->last ? DRY : TYPE);
4161 break;
4162 case STORED:
4163 if (n == 0)
4164 LEAVE
4165 NEEDOUT
4166 t = s->sub.left;
4167 if (t > n) t = n;
4168 if (t > m) t = m;
4169 zmemcpy(q, p, t);
4170 p += t; n -= t;
4171 q += t; m -= t;
4172 if ((s->sub.left -= t) != 0)
4173 break;
4174 Tracev((stderr, "inflate: stored end, %lu total out\n",
4175 z->total_out + (q >= s->read ? q - s->read :
4176 (s->end - s->read) + (q - s->window))));
4177 s->mode = s->last ? DRY : TYPE;
4178 break;
4179 case TABLE:
4180 NEEDBITS(14)
4181 s->sub.trees.table = t = (uInt)b & 0x3fff;
4182 #ifndef PKZIP_BUG_WORKAROUND
4183 if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29)
4184 {
4185 s->mode = BADB;
4186 z->msg = (char*)"too many length or distance symbols";
4187 r = Z_DATA_ERROR;
4188 LEAVE
4189 }
4190 #endif
4191 t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
4192 if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL)
4193 {
4194 r = Z_MEM_ERROR;
4195 LEAVE
4196 }
4197 DUMPBITS(14)
4198 s->sub.trees.index = 0;
4199 Tracev((stderr, "inflate: table sizes ok\n"));
4200 s->mode = BTREE;
4201 case BTREE:
4202 while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10))
4203 {
4204 NEEDBITS(3)
4205 s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7;
4206 DUMPBITS(3)
4207 }
4208 while (s->sub.trees.index < 19)
4209 s->sub.trees.blens[border[s->sub.trees.index++]] = 0;
4210 s->sub.trees.bb = 7;
4211 t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb,
4212 &s->sub.trees.tb, s->hufts, z);
4213 if (t != Z_OK)
4214 {
4215 r = t;
4216 if (r == Z_DATA_ERROR)
4217 {
4218 ZFREE(z, s->sub.trees.blens);
4219 s->mode = BADB;
4220 }
4221 LEAVE
4222 }
4223 s->sub.trees.index = 0;
4224 Tracev((stderr, "inflate: bits tree ok\n"));
4225 s->mode = DTREE;
4226 case DTREE:
4227 while (t = s->sub.trees.table,
4228 s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f))
4229 {
4230 inflate_huft *h;
4231 uInt i, j, c;
4232
4233 t = s->sub.trees.bb;
4234 NEEDBITS(t)
4235 h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]);
4236 t = h->bits;
4237 c = h->base;
4238 if (c < 16)
4239 {
4240 DUMPBITS(t)
4241 s->sub.trees.blens[s->sub.trees.index++] = c;
4242 }
4243 else /* c == 16..18 */
4244 {
4245 i = c == 18 ? 7 : c - 14;
4246 j = c == 18 ? 11 : 3;
4247 NEEDBITS(t + i)
4248 DUMPBITS(t)
4249 j += (uInt)b & inflate_mask[i];
4250 DUMPBITS(i)
4251 i = s->sub.trees.index;
4252 t = s->sub.trees.table;
4253 if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) ||
4254 (c == 16 && i < 1))
4255 {
4256 ZFREE(z, s->sub.trees.blens);
4257 s->mode = BADB;
4258 z->msg = (char*)"invalid bit length repeat";
4259 r = Z_DATA_ERROR;
4260 LEAVE
4261 }
4262 c = c == 16 ? s->sub.trees.blens[i - 1] : 0;
4263 do {
4264 s->sub.trees.blens[i++] = c;
4265 } while (--j);
4266 s->sub.trees.index = i;
4267 }
4268 }
4269 s->sub.trees.tb = Z_NULL;
4270 {
4271 uInt bl, bd;
4272 inflate_huft *tl, *td;
4273 inflate_codes_statef *c;
4274
4275 bl = 9; /* must be <= 9 for lookahead assumptions */
4276 bd = 6; /* must be <= 9 for lookahead assumptions */
4277 t = s->sub.trees.table;
4278 t = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f),
4279 s->sub.trees.blens, &bl, &bd, &tl, &td,
4280 s->hufts, z);
4281 if (t != Z_OK)
4282 {
4283 if (t == (uInt)Z_DATA_ERROR)
4284 {
4285 ZFREE(z, s->sub.trees.blens);
4286 s->mode = BADB;
4287 }
4288 r = t;
4289 LEAVE
4290 }
4291 Tracev((stderr, "inflate: trees ok\n"));
4292 if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL)
4293 {
4294 r = Z_MEM_ERROR;
4295 LEAVE
4296 }
4297 s->sub.decode.codes = c;
4298 }
4299 ZFREE(z, s->sub.trees.blens);
4300 s->mode = CODES;
4301 case CODES:
4302 UPDATE
4303 if ((r = inflate_codes(s, z, r)) != Z_STREAM_END)
4304 return inflate_flush(s, z, r);
4305 r = Z_OK;
4306 inflate_codes_free(s->sub.decode.codes, z);
4307 LOAD
4308 Tracev((stderr, "inflate: codes end, %lu total out\n",
4309 z->total_out + (q >= s->read ? q - s->read :
4310 (s->end - s->read) + (q - s->window))));
4311 if (!s->last)
4312 {
4313 s->mode = TYPE;
4314 break;
4315 }
4316 s->mode = DRY;
4317 case DRY:
4318 FLUSH
4319 if (s->read != s->write)
4320 LEAVE
4321 s->mode = DONEB;
4322 case DONEB:
4323 r = Z_STREAM_END;
4324 LEAVE
4325 case BADB:
4326 r = Z_DATA_ERROR;
4327 LEAVE
4328 default:
4329 r = Z_STREAM_ERROR;
4330 LEAVE
4331 }
4332 }
4333
4334
4335 int inflate_blocks_free(s, z)
4336 inflate_blocks_statef *s;
4337 z_streamp z;
4338 {
4339 inflate_blocks_reset(s, z, Z_NULL);
4340 ZFREE(z, s->window);
4341 ZFREE(z, s->hufts);
4342 ZFREE(z, s);
4343 Tracev((stderr, "inflate: blocks freed\n"));
4344 return Z_OK;
4345 }
4346
4347
4348 void inflate_set_dictionary(s, d, n)
4349 inflate_blocks_statef *s;
4350 const Bytef *d;
4351 uInt n;
4352 {
4353 zmemcpy(s->window, d, n);
4354 s->read = s->write = s->window + n;
4355 }
4356
4357
4358 /* Returns true if inflate is currently at the end of a block generated
4359 * by Z_SYNC_FLUSH or Z_FULL_FLUSH.
4360 * IN assertion: s != Z_NULL
4361 */
4362 int inflate_blocks_sync_point(s)
4363 inflate_blocks_statef *s;
4364 {
4365 return s->mode == LENS;
4366 }
4367 /* --- infblock.c */
4368
4369 /* +++ inftrees.c */
4370 /* inftrees.c -- generate Huffman trees for efficient decoding
4371 * Copyright (C) 1995-2002 Mark Adler
4372 * For conditions of distribution and use, see copyright notice in zlib.h
4373 */
4374
4375 /* #include "zutil.h" */
4376 /* #include "inftrees.h" */
4377
4378 #if !defined(BUILDFIXED) && !defined(STDC)
4379 # define BUILDFIXED /* non ANSI compilers may not accept inffixed.h */
4380 #endif
4381
4382 const char inflate_copyright[] =
4383 " inflate 1.1.4 Copyright 1995-2002 Mark Adler ";
4384 /*
4385 If you use the zlib library in a product, an acknowledgment is welcome
4386 in the documentation of your product. If for some reason you cannot
4387 include such an acknowledgment, I would appreciate that you keep this
4388 copyright string in the executable of your product.
4389 */
4390
4391 #ifndef NO_DUMMY_DECL
4392 struct internal_state {int dummy;}; /* for buggy compilers */
4393 #endif
4394
4395 /* simplify the use of the inflate_huft type with some defines */
4396 #define exop word.what.Exop
4397 #define bits word.what.Bits
4398
4399
4400 local int huft_build OF((
4401 uIntf *, /* code lengths in bits */
4402 uInt, /* number of codes */
4403 uInt, /* number of "simple" codes */
4404 const uIntf *, /* list of base values for non-simple codes */
4405 const uIntf *, /* list of extra bits for non-simple codes */
4406 inflate_huft * FAR*,/* result: starting table */
4407 uIntf *, /* maximum lookup bits (returns actual) */
4408 inflate_huft *, /* space for trees */
4409 uInt *, /* hufts used in space */
4410 uIntf * )); /* space for values */
4411
4412 /* Tables for deflate from PKZIP's appnote.txt. */
4413 local const uInt cplens[31] = { /* Copy lengths for literal codes 257..285 */
4414 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
4415 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
4416 /* see note #13 above about 258 */
4417 local const uInt cplext[31] = { /* Extra bits for literal codes 257..285 */
4418 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
4419 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 112, 112}; /* 112==invalid */
4420 local const uInt cpdist[30] = { /* Copy offsets for distance codes 0..29 */
4421 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
4422 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
4423 8193, 12289, 16385, 24577};
4424 local const uInt cpdext[30] = { /* Extra bits for distance codes */
4425 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
4426 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
4427 12, 12, 13, 13};
4428
4429 /*
4430 Huffman code decoding is performed using a multi-level table lookup.
4431 The fastest way to decode is to simply build a lookup table whose
4432 size is determined by the longest code. However, the time it takes
4433 to build this table can also be a factor if the data being decoded
4434 is not very long. The most common codes are necessarily the
4435 shortest codes, so those codes dominate the decoding time, and hence
4436 the speed. The idea is you can have a shorter table that decodes the
4437 shorter, more probable codes, and then point to subsidiary tables for
4438 the longer codes. The time it costs to decode the longer codes is
4439 then traded against the time it takes to make longer tables.
4440
4441 This results of this trade are in the variables lbits and dbits
4442 below. lbits is the number of bits the first level table for literal/
4443 length codes can decode in one step, and dbits is the same thing for
4444 the distance codes. Subsequent tables are also less than or equal to
4445 those sizes. These values may be adjusted either when all of the
4446 codes are shorter than that, in which case the longest code length in
4447 bits is used, or when the shortest code is *longer* than the requested
4448 table size, in which case the length of the shortest code in bits is
4449 used.
4450
4451 There are two different values for the two tables, since they code a
4452 different number of possibilities each. The literal/length table
4453 codes 286 possible values, or in a flat code, a little over eight
4454 bits. The distance table codes 30 possible values, or a little less
4455 than five bits, flat. The optimum values for speed end up being
4456 about one bit more than those, so lbits is 8+1 and dbits is 5+1.
4457 The optimum values may differ though from machine to machine, and
4458 possibly even between compilers. Your mileage may vary.
4459 */
4460
4461
4462 /* If BMAX needs to be larger than 16, then h and x[] should be uLong. */
4463 #define BMAX 15 /* maximum bit length of any code */
4464
4465 local int huft_build(b, n, s, d, e, t, m, hp, hn, v)
4466 uIntf *b; /* code lengths in bits (all assumed <= BMAX) */
4467 uInt n; /* number of codes (assumed <= 288) */
4468 uInt s; /* number of simple-valued codes (0..s-1) */
4469 const uIntf *d; /* list of base values for non-simple codes */
4470 const uIntf *e; /* list of extra bits for non-simple codes */
4471 inflate_huft * FAR *t; /* result: starting table */
4472 uIntf *m; /* maximum lookup bits, returns actual */
4473 inflate_huft *hp; /* space for trees */
4474 uInt *hn; /* hufts used in space */
4475 uIntf *v; /* working area: values in order of bit length */
4476 /* Given a list of code lengths and a maximum table size, make a set of
4477 tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR
4478 if the given code set is incomplete (the tables are still built in this
4479 case), or Z_DATA_ERROR if the input is invalid. */
4480 {
4481
4482 uInt a; /* counter for codes of length k */
4483 uInt c[BMAX+1]; /* bit length count table */
4484 uInt f; /* i repeats in table every f entries */
4485 int g; /* maximum code length */
4486 int h; /* table level */
4487 register uInt i; /* counter, current code */
4488 register uInt j; /* counter */
4489 register int k; /* number of bits in current code */
4490 int l; /* bits per table (returned in m) */
4491 uInt mask; /* (1 << w) - 1, to avoid cc -O bug on HP */
4492 register uIntf *p; /* pointer into c[], b[], or v[] */
4493 inflate_huft *q; /* points to current table */
4494 struct inflate_huft_s r; /* table entry for structure assignment */
4495 inflate_huft *u[BMAX]; /* table stack */
4496 register int w; /* bits before this table == (l * h) */
4497 uInt x[BMAX+1]; /* bit offsets, then code stack */
4498 uIntf *xp; /* pointer into x */
4499 int y; /* number of dummy codes added */
4500 uInt z; /* number of entries in current table */
4501
4502
4503 /* Generate counts for each bit length */
4504 p = c;
4505 #define C0 *p++ = 0;
4506 #define C2 C0 C0 C0 C0
4507 #define C4 C2 C2 C2 C2
4508 C4 /* clear c[]--assume BMAX+1 is 16 */
4509 p = b; i = n;
4510 do {
4511 c[*p++]++; /* assume all entries <= BMAX */
4512 } while (--i);
4513 if (c[0] == n) /* null input--all zero length codes */
4514 {
4515 *t = (inflate_huft *)Z_NULL;
4516 *m = 0;
4517 return Z_OK;
4518 }
4519
4520
4521 /* Find minimum and maximum length, bound *m by those */
4522 l = *m;
4523 for (j = 1; j <= BMAX; j++)
4524 if (c[j])
4525 break;
4526 k = j; /* minimum code length */
4527 if ((uInt)l < j)
4528 l = j;
4529 for (i = BMAX; i; i--)
4530 if (c[i])
4531 break;
4532 g = i; /* maximum code length */
4533 if ((uInt)l > i)
4534 l = i;
4535 *m = l;
4536
4537
4538 /* Adjust last length count to fill out codes, if needed */
4539 for (y = 1 << j; j < i; j++, y <<= 1)
4540 if ((y -= c[j]) < 0)
4541 return Z_DATA_ERROR;
4542 if ((y -= c[i]) < 0)
4543 return Z_DATA_ERROR;
4544 c[i] += y;
4545
4546
4547 /* Generate starting offsets into the value table for each length */
4548 x[1] = j = 0;
4549 p = c + 1; xp = x + 2;
4550 while (--i) { /* note that i == g from above */
4551 *xp++ = (j += *p++);
4552 }
4553
4554
4555 /* Make a table of values in order of bit lengths */
4556 p = b; i = 0;
4557 do {
4558 if ((j = *p++) != 0)
4559 v[x[j]++] = i;
4560 } while (++i < n);
4561 n = x[g]; /* set n to length of v */
4562
4563
4564 /* Generate the Huffman codes and for each, make the table entries */
4565 x[0] = i = 0; /* first Huffman code is zero */
4566 p = v; /* grab values in bit order */
4567 h = -1; /* no tables yet--level -1 */
4568 w = -l; /* bits decoded == (l * h) */
4569 u[0] = (inflate_huft *)Z_NULL; /* just to keep compilers happy */
4570 q = (inflate_huft *)Z_NULL; /* ditto */
4571 z = 0; /* ditto */
4572
4573 /* go through the bit lengths (k already is bits in shortest code) */
4574 for (; k <= g; k++)
4575 {
4576 a = c[k];
4577 while (a--)
4578 {
4579 /* here i is the Huffman code of length k bits for value *p */
4580 /* make tables up to required level */
4581 while (k > w + l)
4582 {
4583 h++;
4584 w += l; /* previous table always l bits */
4585
4586 /* compute minimum size table less than or equal to l bits */
4587 z = g - w;
4588 z = z > (uInt)l ? l : z; /* table size upper limit */
4589 if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */
4590 { /* too few codes for k-w bit table */
4591 f -= a + 1; /* deduct codes from patterns left */
4592 xp = c + k;
4593 if (j < z)
4594 while (++j < z) /* try smaller tables up to z bits */
4595 {
4596 if ((f <<= 1) <= *++xp)
4597 break; /* enough codes to use up j bits */
4598 f -= *xp; /* else deduct codes from patterns */
4599 }
4600 }
4601 z = 1 << j; /* table entries for j-bit table */
4602
4603 /* allocate new table */
4604 if (*hn + z > MANY) /* (note: doesn't matter for fixed) */
4605 return Z_DATA_ERROR; /* overflow of MANY */
4606 u[h] = q = hp + *hn;
4607 *hn += z;
4608
4609 /* connect to last table, if there is one */
4610 if (h)
4611 {
4612 x[h] = i; /* save pattern for backing up */
4613 r.bits = (Byte)l; /* bits to dump before this table */
4614 r.exop = (Byte)j; /* bits in this table */
4615 j = i >> (w - l);
4616 r.base = (uInt)(q - u[h-1] - j); /* offset to this table */
4617 u[h-1][j] = r; /* connect to last table */
4618 }
4619 else
4620 *t = q; /* first table is returned result */
4621 }
4622
4623 /* set up table entry in r */
4624 r.bits = (Byte)(k - w);
4625 if (p >= v + n)
4626 r.exop = 128 + 64; /* out of values--invalid code */
4627 else if (*p < s)
4628 {
4629 r.exop = (Byte)(*p < 256 ? 0 : 32 + 64); /* 256 is end-of-block */
4630 r.base = *p++; /* simple code is just the value */
4631 }
4632 else
4633 {
4634 r.exop = (Byte)(e[*p - s] + 16 + 64);/* non-simple--look up in lists */
4635 r.base = d[*p++ - s];
4636 }
4637
4638 /* fill code-like entries with r */
4639 f = 1 << (k - w);
4640 for (j = i >> w; j < z; j += f)
4641 q[j] = r;
4642
4643 /* backwards increment the k-bit code i */
4644 for (j = 1 << (k - 1); i & j; j >>= 1)
4645 i ^= j;
4646 i ^= j;
4647
4648 /* backup over finished tables */
4649 mask = (1 << w) - 1; /* needed on HP, cc -O bug */
4650 while ((i & mask) != x[h])
4651 {
4652 h--; /* don't need to update q */
4653 w -= l;
4654 mask = (1 << w) - 1;
4655 }
4656 }
4657 }
4658
4659
4660 /* Return Z_BUF_ERROR if we were given an incomplete table */
4661 return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK;
4662 }
4663
4664
4665 int inflate_trees_bits(c, bb, tb, hp, z)
4666 uIntf *c; /* 19 code lengths */
4667 uIntf *bb; /* bits tree desired/actual depth */
4668 inflate_huft * FAR *tb; /* bits tree result */
4669 inflate_huft *hp; /* space for trees */
4670 z_streamp z; /* for messages */
4671 {
4672 int r;
4673 uInt hn = 0; /* hufts used in space */
4674 uIntf *v; /* work area for huft_build */
4675
4676 if ((v = (uIntf*)ZALLOC(z, 19, sizeof(uInt))) == Z_NULL)
4677 return Z_MEM_ERROR;
4678 r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL,
4679 tb, bb, hp, &hn, v);
4680 if (r == Z_DATA_ERROR)
4681 z->msg = (char*)"oversubscribed dynamic bit lengths tree";
4682 else if (r == Z_BUF_ERROR || *bb == 0)
4683 {
4684 z->msg = (char*)"incomplete dynamic bit lengths tree";
4685 r = Z_DATA_ERROR;
4686 }
4687 ZFREE(z, v);
4688 return r;
4689 }
4690
4691
4692 int inflate_trees_dynamic(nl, nd, c, bl, bd, tl, td, hp, z)
4693 uInt nl; /* number of literal/length codes */
4694 uInt nd; /* number of distance codes */
4695 uIntf *c; /* that many (total) code lengths */
4696 uIntf *bl; /* literal desired/actual bit depth */
4697 uIntf *bd; /* distance desired/actual bit depth */
4698 inflate_huft * FAR *tl; /* literal/length tree result */
4699 inflate_huft * FAR *td; /* distance tree result */
4700 inflate_huft *hp; /* space for trees */
4701 z_streamp z; /* for messages */
4702 {
4703 int r;
4704 uInt hn = 0; /* hufts used in space */
4705 uIntf *v; /* work area for huft_build */
4706
4707 /* allocate work area */
4708 if ((v = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
4709 return Z_MEM_ERROR;
4710
4711 /* build literal/length tree */
4712 r = huft_build(c, nl, 257, cplens, cplext, tl, bl, hp, &hn, v);
4713 if (r != Z_OK || *bl == 0)
4714 {
4715 if (r == Z_DATA_ERROR)
4716 z->msg = (char*)"oversubscribed literal/length tree";
4717 else if (r != Z_MEM_ERROR)
4718 {
4719 z->msg = (char*)"incomplete literal/length tree";
4720 r = Z_DATA_ERROR;
4721 }
4722 ZFREE(z, v);
4723 return r;
4724 }
4725
4726 /* build distance tree */
4727 r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, hp, &hn, v);
4728 if (r != Z_OK || (*bd == 0 && nl > 257))
4729 {
4730 if (r == Z_DATA_ERROR)
4731 z->msg = (char*)"oversubscribed distance tree";
4732 else if (r == Z_BUF_ERROR) {
4733 #ifdef PKZIP_BUG_WORKAROUND
4734 r = Z_OK;
4735 }
4736 #else
4737 z->msg = (char*)"incomplete distance tree";
4738 r = Z_DATA_ERROR;
4739 }
4740 else if (r != Z_MEM_ERROR)
4741 {
4742 z->msg = (char*)"empty distance tree with lengths";
4743 r = Z_DATA_ERROR;
4744 }
4745 ZFREE(z, v);
4746 return r;
4747 #endif
4748 }
4749
4750 /* done */
4751 ZFREE(z, v);
4752 return Z_OK;
4753 }
4754
4755
4756 /* build fixed tables only once--keep them here */
4757 #ifdef BUILDFIXED
4758 local int fixed_built = 0;
4759 #define FIXEDH 544 /* number of hufts used by fixed tables */
4760 local inflate_huft *fixed_mem = NULL;
4761 local uInt fixed_bl;
4762 local uInt fixed_bd;
4763 local inflate_huft *fixed_tl;
4764 local inflate_huft *fixed_td;
4765 #else
4766 /* +++ inffixed.h */
4767 /* inffixed.h -- table for decoding fixed codes
4768 * Generated automatically by the maketree.c program
4769 */
4770
4771 /* WARNING: this file should *not* be used by applications. It is
4772 part of the implementation of the compression library and is
4773 subject to change. Applications should only use zlib.h.
4774 */
4775
4776 local uInt fixed_bl = 9;
4777 local uInt fixed_bd = 5;
4778 local inflate_huft fixed_tl[] = {
4779 {{{96,7}},256}, {{{0,8}},80}, {{{0,8}},16}, {{{84,8}},115},
4780 {{{82,7}},31}, {{{0,8}},112}, {{{0,8}},48}, {{{0,9}},192},
4781 {{{80,7}},10}, {{{0,8}},96}, {{{0,8}},32}, {{{0,9}},160},
4782 {{{0,8}},0}, {{{0,8}},128}, {{{0,8}},64}, {{{0,9}},224},
4783 {{{80,7}},6}, {{{0,8}},88}, {{{0,8}},24}, {{{0,9}},144},
4784 {{{83,7}},59}, {{{0,8}},120}, {{{0,8}},56}, {{{0,9}},208},
4785 {{{81,7}},17}, {{{0,8}},104}, {{{0,8}},40}, {{{0,9}},176},
4786 {{{0,8}},8}, {{{0,8}},136}, {{{0,8}},72}, {{{0,9}},240},
4787 {{{80,7}},4}, {{{0,8}},84}, {{{0,8}},20}, {{{85,8}},227},
4788 {{{83,7}},43}, {{{0,8}},116}, {{{0,8}},52}, {{{0,9}},200},
4789 {{{81,7}},13}, {{{0,8}},100}, {{{0,8}},36}, {{{0,9}},168},
4790 {{{0,8}},4}, {{{0,8}},132}, {{{0,8}},68}, {{{0,9}},232},
4791 {{{80,7}},8}, {{{0,8}},92}, {{{0,8}},28}, {{{0,9}},152},
4792 {{{84,7}},83}, {{{0,8}},124}, {{{0,8}},60}, {{{0,9}},216},
4793 {{{82,7}},23}, {{{0,8}},108}, {{{0,8}},44}, {{{0,9}},184},
4794 {{{0,8}},12}, {{{0,8}},140}, {{{0,8}},76}, {{{0,9}},248},
4795 {{{80,7}},3}, {{{0,8}},82}, {{{0,8}},18}, {{{85,8}},163},
4796 {{{83,7}},35}, {{{0,8}},114}, {{{0,8}},50}, {{{0,9}},196},
4797 {{{81,7}},11}, {{{0,8}},98}, {{{0,8}},34}, {{{0,9}},164},
4798 {{{0,8}},2}, {{{0,8}},130}, {{{0,8}},66}, {{{0,9}},228},
4799 {{{80,7}},7}, {{{0,8}},90}, {{{0,8}},26}, {{{0,9}},148},
4800 {{{84,7}},67}, {{{0,8}},122}, {{{0,8}},58}, {{{0,9}},212},
4801 {{{82,7}},19}, {{{0,8}},106}, {{{0,8}},42}, {{{0,9}},180},
4802 {{{0,8}},10}, {{{0,8}},138}, {{{0,8}},74}, {{{0,9}},244},
4803 {{{80,7}},5}, {{{0,8}},86}, {{{0,8}},22}, {{{192,8}},0},
4804 {{{83,7}},51}, {{{0,8}},118}, {{{0,8}},54}, {{{0,9}},204},
4805 {{{81,7}},15}, {{{0,8}},102}, {{{0,8}},38}, {{{0,9}},172},
4806 {{{0,8}},6}, {{{0,8}},134}, {{{0,8}},70}, {{{0,9}},236},
4807 {{{80,7}},9}, {{{0,8}},94}, {{{0,8}},30}, {{{0,9}},156},
4808 {{{84,7}},99}, {{{0,8}},126}, {{{0,8}},62}, {{{0,9}},220},
4809 {{{82,7}},27}, {{{0,8}},110}, {{{0,8}},46}, {{{0,9}},188},
4810 {{{0,8}},14}, {{{0,8}},142}, {{{0,8}},78}, {{{0,9}},252},
4811 {{{96,7}},256}, {{{0,8}},81}, {{{0,8}},17}, {{{85,8}},131},
4812 {{{82,7}},31}, {{{0,8}},113}, {{{0,8}},49}, {{{0,9}},194},
4813 {{{80,7}},10}, {{{0,8}},97}, {{{0,8}},33}, {{{0,9}},162},
4814 {{{0,8}},1}, {{{0,8}},129}, {{{0,8}},65}, {{{0,9}},226},
4815 {{{80,7}},6}, {{{0,8}},89}, {{{0,8}},25}, {{{0,9}},146},
4816 {{{83,7}},59}, {{{0,8}},121}, {{{0,8}},57}, {{{0,9}},210},
4817 {{{81,7}},17}, {{{0,8}},105}, {{{0,8}},41}, {{{0,9}},178},
4818 {{{0,8}},9}, {{{0,8}},137}, {{{0,8}},73}, {{{0,9}},242},
4819 {{{80,7}},4}, {{{0,8}},85}, {{{0,8}},21}, {{{80,8}},258},
4820 {{{83,7}},43}, {{{0,8}},117}, {{{0,8}},53}, {{{0,9}},202},
4821 {{{81,7}},13}, {{{0,8}},101}, {{{0,8}},37}, {{{0,9}},170},
4822 {{{0,8}},5}, {{{0,8}},133}, {{{0,8}},69}, {{{0,9}},234},
4823 {{{80,7}},8}, {{{0,8}},93}, {{{0,8}},29}, {{{0,9}},154},
4824 {{{84,7}},83}, {{{0,8}},125}, {{{0,8}},61}, {{{0,9}},218},
4825 {{{82,7}},23}, {{{0,8}},109}, {{{0,8}},45}, {{{0,9}},186},
4826 {{{0,8}},13}, {{{0,8}},141}, {{{0,8}},77}, {{{0,9}},250},
4827 {{{80,7}},3}, {{{0,8}},83}, {{{0,8}},19}, {{{85,8}},195},
4828 {{{83,7}},35}, {{{0,8}},115}, {{{0,8}},51}, {{{0,9}},198},
4829 {{{81,7}},11}, {{{0,8}},99}, {{{0,8}},35}, {{{0,9}},166},
4830 {{{0,8}},3}, {{{0,8}},131}, {{{0,8}},67}, {{{0,9}},230},
4831 {{{80,7}},7}, {{{0,8}},91}, {{{0,8}},27}, {{{0,9}},150},
4832 {{{84,7}},67}, {{{0,8}},123}, {{{0,8}},59}, {{{0,9}},214},
4833 {{{82,7}},19}, {{{0,8}},107}, {{{0,8}},43}, {{{0,9}},182},
4834 {{{0,8}},11}, {{{0,8}},139}, {{{0,8}},75}, {{{0,9}},246},
4835 {{{80,7}},5}, {{{0,8}},87}, {{{0,8}},23}, {{{192,8}},0},
4836 {{{83,7}},51}, {{{0,8}},119}, {{{0,8}},55}, {{{0,9}},206},
4837 {{{81,7}},15}, {{{0,8}},103}, {{{0,8}},39}, {{{0,9}},174},
4838 {{{0,8}},7}, {{{0,8}},135}, {{{0,8}},71}, {{{0,9}},238},
4839 {{{80,7}},9}, {{{0,8}},95}, {{{0,8}},31}, {{{0,9}},158},
4840 {{{84,7}},99}, {{{0,8}},127}, {{{0,8}},63}, {{{0,9}},222},
4841 {{{82,7}},27}, {{{0,8}},111}, {{{0,8}},47}, {{{0,9}},190},
4842 {{{0,8}},15}, {{{0,8}},143}, {{{0,8}},79}, {{{0,9}},254},
4843 {{{96,7}},256}, {{{0,8}},80}, {{{0,8}},16}, {{{84,8}},115},
4844 {{{82,7}},31}, {{{0,8}},112}, {{{0,8}},48}, {{{0,9}},193},
4845 {{{80,7}},10}, {{{0,8}},96}, {{{0,8}},32}, {{{0,9}},161},
4846 {{{0,8}},0}, {{{0,8}},128}, {{{0,8}},64}, {{{0,9}},225},
4847 {{{80,7}},6}, {{{0,8}},88}, {{{0,8}},24}, {{{0,9}},145},
4848 {{{83,7}},59}, {{{0,8}},120}, {{{0,8}},56}, {{{0,9}},209},
4849 {{{81,7}},17}, {{{0,8}},104}, {{{0,8}},40}, {{{0,9}},177},
4850 {{{0,8}},8}, {{{0,8}},136}, {{{0,8}},72}, {{{0,9}},241},
4851 {{{80,7}},4}, {{{0,8}},84}, {{{0,8}},20}, {{{85,8}},227},
4852 {{{83,7}},43}, {{{0,8}},116}, {{{0,8}},52}, {{{0,9}},201},
4853 {{{81,7}},13}, {{{0,8}},100}, {{{0,8}},36}, {{{0,9}},169},
4854 {{{0,8}},4}, {{{0,8}},132}, {{{0,8}},68}, {{{0,9}},233},
4855 {{{80,7}},8}, {{{0,8}},92}, {{{0,8}},28}, {{{0,9}},153},
4856 {{{84,7}},83}, {{{0,8}},124}, {{{0,8}},60}, {{{0,9}},217},
4857 {{{82,7}},23}, {{{0,8}},108}, {{{0,8}},44}, {{{0,9}},185},
4858 {{{0,8}},12}, {{{0,8}},140}, {{{0,8}},76}, {{{0,9}},249},
4859 {{{80,7}},3}, {{{0,8}},82}, {{{0,8}},18}, {{{85,8}},163},
4860 {{{83,7}},35}, {{{0,8}},114}, {{{0,8}},50}, {{{0,9}},197},
4861 {{{81,7}},11}, {{{0,8}},98}, {{{0,8}},34}, {{{0,9}},165},
4862 {{{0,8}},2}, {{{0,8}},130}, {{{0,8}},66}, {{{0,9}},229},
4863 {{{80,7}},7}, {{{0,8}},90}, {{{0,8}},26}, {{{0,9}},149},
4864 {{{84,7}},67}, {{{0,8}},122}, {{{0,8}},58}, {{{0,9}},213},
4865 {{{82,7}},19}, {{{0,8}},106}, {{{0,8}},42}, {{{0,9}},181},
4866 {{{0,8}},10}, {{{0,8}},138}, {{{0,8}},74}, {{{0,9}},245},
4867 {{{80,7}},5}, {{{0,8}},86}, {{{0,8}},22}, {{{192,8}},0},
4868 {{{83,7}},51}, {{{0,8}},118}, {{{0,8}},54}, {{{0,9}},205},
4869 {{{81,7}},15}, {{{0,8}},102}, {{{0,8}},38}, {{{0,9}},173},
4870 {{{0,8}},6}, {{{0,8}},134}, {{{0,8}},70}, {{{0,9}},237},
4871 {{{80,7}},9}, {{{0,8}},94}, {{{0,8}},30}, {{{0,9}},157},
4872 {{{84,7}},99}, {{{0,8}},126}, {{{0,8}},62}, {{{0,9}},221},
4873 {{{82,7}},27}, {{{0,8}},110}, {{{0,8}},46}, {{{0,9}},189},
4874 {{{0,8}},14}, {{{0,8}},142}, {{{0,8}},78}, {{{0,9}},253},
4875 {{{96,7}},256}, {{{0,8}},81}, {{{0,8}},17}, {{{85,8}},131},
4876 {{{82,7}},31}, {{{0,8}},113}, {{{0,8}},49}, {{{0,9}},195},
4877 {{{80,7}},10}, {{{0,8}},97}, {{{0,8}},33}, {{{0,9}},163},
4878 {{{0,8}},1}, {{{0,8}},129}, {{{0,8}},65}, {{{0,9}},227},
4879 {{{80,7}},6}, {{{0,8}},89}, {{{0,8}},25}, {{{0,9}},147},
4880 {{{83,7}},59}, {{{0,8}},121}, {{{0,8}},57}, {{{0,9}},211},
4881 {{{81,7}},17}, {{{0,8}},105}, {{{0,8}},41}, {{{0,9}},179},
4882 {{{0,8}},9}, {{{0,8}},137}, {{{0,8}},73}, {{{0,9}},243},
4883 {{{80,7}},4}, {{{0,8}},85}, {{{0,8}},21}, {{{80,8}},258},
4884 {{{83,7}},43}, {{{0,8}},117}, {{{0,8}},53}, {{{0,9}},203},
4885 {{{81,7}},13}, {{{0,8}},101}, {{{0,8}},37}, {{{0,9}},171},
4886 {{{0,8}},5}, {{{0,8}},133}, {{{0,8}},69}, {{{0,9}},235},
4887 {{{80,7}},8}, {{{0,8}},93}, {{{0,8}},29}, {{{0,9}},155},
4888 {{{84,7}},83}, {{{0,8}},125}, {{{0,8}},61}, {{{0,9}},219},
4889 {{{82,7}},23}, {{{0,8}},109}, {{{0,8}},45}, {{{0,9}},187},
4890 {{{0,8}},13}, {{{0,8}},141}, {{{0,8}},77}, {{{0,9}},251},
4891 {{{80,7}},3}, {{{0,8}},83}, {{{0,8}},19}, {{{85,8}},195},
4892 {{{83,7}},35}, {{{0,8}},115}, {{{0,8}},51}, {{{0,9}},199},
4893 {{{81,7}},11}, {{{0,8}},99}, {{{0,8}},35}, {{{0,9}},167},
4894 {{{0,8}},3}, {{{0,8}},131}, {{{0,8}},67}, {{{0,9}},231},
4895 {{{80,7}},7}, {{{0,8}},91}, {{{0,8}},27}, {{{0,9}},151},
4896 {{{84,7}},67}, {{{0,8}},123}, {{{0,8}},59}, {{{0,9}},215},
4897 {{{82,7}},19}, {{{0,8}},107}, {{{0,8}},43}, {{{0,9}},183},
4898 {{{0,8}},11}, {{{0,8}},139}, {{{0,8}},75}, {{{0,9}},247},
4899 {{{80,7}},5}, {{{0,8}},87}, {{{0,8}},23}, {{{192,8}},0},
4900 {{{83,7}},51}, {{{0,8}},119}, {{{0,8}},55}, {{{0,9}},207},
4901 {{{81,7}},15}, {{{0,8}},103}, {{{0,8}},39}, {{{0,9}},175},
4902 {{{0,8}},7}, {{{0,8}},135}, {{{0,8}},71}, {{{0,9}},239},
4903 {{{80,7}},9}, {{{0,8}},95}, {{{0,8}},31}, {{{0,9}},159},
4904 {{{84,7}},99}, {{{0,8}},127}, {{{0,8}},63}, {{{0,9}},223},
4905 {{{82,7}},27}, {{{0,8}},111}, {{{0,8}},47}, {{{0,9}},191},
4906 {{{0,8}},15}, {{{0,8}},143}, {{{0,8}},79}, {{{0,9}},255}
4907 };
4908 local inflate_huft fixed_td[] = {
4909 {{{80,5}},1}, {{{87,5}},257}, {{{83,5}},17}, {{{91,5}},4097},
4910 {{{81,5}},5}, {{{89,5}},1025}, {{{85,5}},65}, {{{93,5}},16385},
4911 {{{80,5}},3}, {{{88,5}},513}, {{{84,5}},33}, {{{92,5}},8193},
4912 {{{82,5}},9}, {{{90,5}},2049}, {{{86,5}},129}, {{{192,5}},24577},
4913 {{{80,5}},2}, {{{87,5}},385}, {{{83,5}},25}, {{{91,5}},6145},
4914 {{{81,5}},7}, {{{89,5}},1537}, {{{85,5}},97}, {{{93,5}},24577},
4915 {{{80,5}},4}, {{{88,5}},769}, {{{84,5}},49}, {{{92,5}},12289},
4916 {{{82,5}},13}, {{{90,5}},3073}, {{{86,5}},193}, {{{192,5}},24577}
4917 };
4918 /* --- inffixed.h */
4919 #endif
4920
4921
4922 int inflate_trees_fixed(bl, bd, tl, td, z)
4923 uIntf *bl; /* literal desired/actual bit depth */
4924 uIntf *bd; /* distance desired/actual bit depth */
4925 inflate_huft * FAR *tl; /* literal/length tree result */
4926 inflate_huft * FAR *td; /* distance tree result */
4927 z_streamp z; /* for memory allocation */
4928 {
4929 #ifdef BUILDFIXED
4930 /* build fixed tables if not already */
4931 if (!fixed_built)
4932 {
4933 int k; /* temporary variable */
4934 uInt f = 0; /* number of hufts used in fixed_mem */
4935 uIntf *c; /* length list for huft_build */
4936 uIntf *v; /* work area for huft_build */
4937
4938 /* allocate memory */
4939 if ((c = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
4940 return Z_MEM_ERROR;
4941 if ((v = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
4942 {
4943 ZFREE(z, c);
4944 return Z_MEM_ERROR;
4945 }
4946
4947 if ((fixed_mem = (inflate_huft*)ZALLOC(z, FIXEDH, sizeof(inflate_huft))) == Z_NULL)
4948 {
4949 ZFREE(z, c);
4950 ZFREE(z, v);
4951 return Z_MEM_ERROR;
4952 }
4953
4954 /* literal table */
4955 for (k = 0; k < 144; k++)
4956 c[k] = 8;
4957 for (; k < 256; k++)
4958 c[k] = 9;
4959 for (; k < 280; k++)
4960 c[k] = 7;
4961 for (; k < 288; k++)
4962 c[k] = 8;
4963 fixed_bl = 9;
4964 huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl,
4965 fixed_mem, &f, v);
4966
4967 /* distance table */
4968 for (k = 0; k < 30; k++)
4969 c[k] = 5;
4970 fixed_bd = 5;
4971 huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd,
4972 fixed_mem, &f, v);
4973
4974 /* done */
4975 ZFREE(z, v);
4976 ZFREE(z, c);
4977 fixed_built = 1;
4978 }
4979 #endif
4980 *bl = fixed_bl;
4981 *bd = fixed_bd;
4982 *tl = fixed_tl;
4983 *td = fixed_td;
4984 return Z_OK;
4985 }
4986 /* --- inftrees.c */
4987
4988 /* +++ infcodes.c */
4989 /* infcodes.c -- process literals and length/distance pairs
4990 * Copyright (C) 1995-2002 Mark Adler
4991 * For conditions of distribution and use, see copyright notice in zlib.h
4992 */
4993
4994 /* #include "zutil.h" */
4995 /* #include "inftrees.h" */
4996 /* #include "infblock.h" */
4997 /* #include "infcodes.h" */
4998 /* #include "infutil.h" */
4999
5000 /* +++ inffast.h */
5001 /* inffast.h -- header to use inffast.c
5002 * Copyright (C) 1995-2002 Mark Adler
5003 * For conditions of distribution and use, see copyright notice in zlib.h
5004 */
5005
5006 /* WARNING: this file should *not* be used by applications. It is
5007 part of the implementation of the compression library and is
5008 subject to change. Applications should only use zlib.h.
5009 */
5010
5011 extern int inflate_fast OF((
5012 uInt,
5013 uInt,
5014 inflate_huft *,
5015 inflate_huft *,
5016 inflate_blocks_statef *,
5017 z_streamp ));
5018 /* --- inffast.h */
5019
5020 /* simplify the use of the inflate_huft type with some defines */
5021 #define exop word.what.Exop
5022 #define bits word.what.Bits
5023
5024 typedef enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
5025 START, /* x: set up for LEN */
5026 LEN, /* i: get length/literal/eob next */
5027 LENEXT, /* i: getting length extra (have base) */
5028 DIST, /* i: get distance next */
5029 DISTEXT, /* i: getting distance extra */
5030 COPY, /* o: copying bytes in window, waiting for space */
5031 LIT, /* o: got literal, waiting for output space */
5032 WASH, /* o: got eob, possibly still output waiting */
5033 END, /* x: got eob and all data flushed */
5034 BADCODE} /* x: got error */
5035 inflate_codes_mode;
5036
5037 /* inflate codes private state */
5038 struct inflate_codes_state {
5039
5040 /* mode */
5041 inflate_codes_mode mode; /* current inflate_codes mode */
5042
5043 /* mode dependent information */
5044 uInt len;
5045 union {
5046 struct {
5047 inflate_huft *tree; /* pointer into tree */
5048 uInt need; /* bits needed */
5049 } code; /* if LEN or DIST, where in tree */
5050 uInt lit; /* if LIT, literal */
5051 struct {
5052 uInt get; /* bits to get for extra */
5053 uInt dist; /* distance back to copy from */
5054 } copy; /* if EXT or COPY, where and how much */
5055 } sub; /* submode */
5056
5057 /* mode independent information */
5058 Byte lbits; /* ltree bits decoded per branch */
5059 Byte dbits; /* dtree bits decoder per branch */
5060 inflate_huft *ltree; /* literal/length/eob tree */
5061 inflate_huft *dtree; /* distance tree */
5062
5063 };
5064
5065
5066 inflate_codes_statef *inflate_codes_new(bl, bd, tl, td, z)
5067 uInt bl, bd;
5068 inflate_huft *tl;
5069 inflate_huft *td; /* need separate declaration for Borland C++ */
5070 z_streamp z;
5071 {
5072 inflate_codes_statef *c;
5073
5074 if ((c = (inflate_codes_statef *)
5075 ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL)
5076 {
5077 c->mode = START;
5078 c->lbits = (Byte)bl;
5079 c->dbits = (Byte)bd;
5080 c->ltree = tl;
5081 c->dtree = td;
5082 Tracev((stderr, "inflate: codes new\n"));
5083 }
5084 return c;
5085 }
5086
5087
5088 int inflate_codes(s, z, r)
5089 inflate_blocks_statef *s;
5090 z_streamp z;
5091 int r;
5092 {
5093 uInt j; /* temporary storage */
5094 inflate_huft *t; /* temporary pointer */
5095 uInt e; /* extra bits or operation */
5096 uLong b; /* bit buffer */
5097 uInt k; /* bits in bit buffer */
5098 Bytef *p; /* input data pointer */
5099 uInt n; /* bytes available there */
5100 Bytef *q; /* output window write pointer */
5101 uInt m; /* bytes to end of window or read pointer */
5102 Bytef *f; /* pointer to copy strings from */
5103 inflate_codes_statef *c = s->sub.decode.codes; /* codes state */
5104
5105 /* copy input/output information to locals (UPDATE macro restores) */
5106 LOAD
5107
5108 /* process input and output based on current state */
5109 while (1) switch (c->mode)
5110 { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
5111 case START: /* x: set up for LEN */
5112 #ifndef SLOW
5113 if (m >= 258 && n >= 10)
5114 {
5115 UPDATE
5116 r = inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z);
5117 LOAD
5118 if (r != Z_OK)
5119 {
5120 c->mode = r == Z_STREAM_END ? WASH : BADCODE;
5121 break;
5122 }
5123 }
5124 #endif /* !SLOW */
5125 c->sub.code.need = c->lbits;
5126 c->sub.code.tree = c->ltree;
5127 c->mode = LEN;
5128 case LEN: /* i: get length/literal/eob next */
5129 j = c->sub.code.need;
5130 NEEDBITS(j)
5131 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
5132 DUMPBITS(t->bits)
5133 e = (uInt)(t->exop);
5134 if (e == 0) /* literal */
5135 {
5136 c->sub.lit = t->base;
5137 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5138 "inflate: literal '%c'\n" :
5139 "inflate: literal 0x%02x\n", t->base));
5140 c->mode = LIT;
5141 break;
5142 }
5143 if (e & 16) /* length */
5144 {
5145 c->sub.copy.get = e & 15;
5146 c->len = t->base;
5147 c->mode = LENEXT;
5148 break;
5149 }
5150 if ((e & 64) == 0) /* next table */
5151 {
5152 c->sub.code.need = e;
5153 c->sub.code.tree = t + t->base;
5154 break;
5155 }
5156 if (e & 32) /* end of block */
5157 {
5158 Tracevv((stderr, "inflate: end of block\n"));
5159 c->mode = WASH;
5160 break;
5161 }
5162 c->mode = BADCODE; /* invalid code */
5163 z->msg = (char*)"invalid literal/length code";
5164 r = Z_DATA_ERROR;
5165 LEAVE
5166 case LENEXT: /* i: getting length extra (have base) */
5167 j = c->sub.copy.get;
5168 NEEDBITS(j)
5169 c->len += (uInt)b & inflate_mask[j];
5170 DUMPBITS(j)
5171 c->sub.code.need = c->dbits;
5172 c->sub.code.tree = c->dtree;
5173 Tracevv((stderr, "inflate: length %u\n", c->len));
5174 c->mode = DIST;
5175 case DIST: /* i: get distance next */
5176 j = c->sub.code.need;
5177 NEEDBITS(j)
5178 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
5179 DUMPBITS(t->bits)
5180 e = (uInt)(t->exop);
5181 if (e & 16) /* distance */
5182 {
5183 c->sub.copy.get = e & 15;
5184 c->sub.copy.dist = t->base;
5185 c->mode = DISTEXT;
5186 break;
5187 }
5188 if ((e & 64) == 0) /* next table */
5189 {
5190 c->sub.code.need = e;
5191 c->sub.code.tree = t + t->base;
5192 break;
5193 }
5194 c->mode = BADCODE; /* invalid code */
5195 z->msg = (char*)"invalid distance code";
5196 r = Z_DATA_ERROR;
5197 LEAVE
5198 case DISTEXT: /* i: getting distance extra */
5199 j = c->sub.copy.get;
5200 NEEDBITS(j)
5201 c->sub.copy.dist += (uInt)b & inflate_mask[j];
5202 DUMPBITS(j)
5203 Tracevv((stderr, "inflate: distance %u\n", c->sub.copy.dist));
5204 c->mode = COPY;
5205 case COPY: /* o: copying bytes in window, waiting for space */
5206 f = q - c->sub.copy.dist;
5207 while (f < s->window) /* modulo window size-"while" instead */
5208 f += s->end - s->window; /* of "if" handles invalid distances */
5209 while (c->len)
5210 {
5211 NEEDOUT
5212 OUTBYTE(*f++)
5213 if (f == s->end)
5214 f = s->window;
5215 c->len--;
5216 }
5217 c->mode = START;
5218 break;
5219 case LIT: /* o: got literal, waiting for output space */
5220 NEEDOUT
5221 OUTBYTE(c->sub.lit)
5222 c->mode = START;
5223 break;
5224 case WASH: /* o: got eob, possibly more output */
5225 if (k > 7) /* return unused byte, if any */
5226 {
5227 Assert(k < 16, "inflate_codes grabbed too many bytes")
5228 k -= 8;
5229 n++;
5230 p--; /* can always return one */
5231 }
5232 FLUSH
5233 if (s->read != s->write)
5234 LEAVE
5235 c->mode = END;
5236 case END:
5237 r = Z_STREAM_END;
5238 LEAVE
5239 case BADCODE: /* x: got error */
5240 r = Z_DATA_ERROR;
5241 LEAVE
5242 default:
5243 r = Z_STREAM_ERROR;
5244 LEAVE
5245 }
5246 #ifdef NEED_DUMMY_RETURN
5247 return Z_STREAM_ERROR; /* Some dumb compilers complain without this */
5248 #endif
5249 }
5250
5251
5252 void inflate_codes_free(c, z)
5253 inflate_codes_statef *c;
5254 z_streamp z;
5255 {
5256 ZFREE(z, c);
5257 Tracev((stderr, "inflate: codes free\n"));
5258 }
5259 /* --- infcodes.c */
5260
5261 /* +++ infutil.c */
5262 /* inflate_util.c -- data and routines common to blocks and codes
5263 * Copyright (C) 1995-2002 Mark Adler
5264 * For conditions of distribution and use, see copyright notice in zlib.h
5265 */
5266
5267 /* #include "zutil.h" */
5268 /* #include "infblock.h" */
5269 /* #include "inftrees.h" */
5270 /* #include "infcodes.h" */
5271 /* #include "infutil.h" */
5272
5273 #ifndef NO_DUMMY_DECL
5274 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
5275 #endif
5276
5277 /* And'ing with mask[n] masks the lower n bits */
5278 uInt inflate_mask[17] = {
5279 0x0000,
5280 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
5281 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
5282 };
5283
5284
5285 /* copy as much as possible from the sliding window to the output area */
5286 int inflate_flush(s, z, r)
5287 inflate_blocks_statef *s;
5288 z_streamp z;
5289 int r;
5290 {
5291 uInt n;
5292 Bytef *p;
5293 Bytef *q;
5294
5295 /* local copies of source and destination pointers */
5296 p = z->next_out;
5297 q = s->read;
5298
5299 /* compute number of bytes to copy as far as end of window */
5300 n = (uInt)((q <= s->write ? s->write : s->end) - q);
5301 if (n > z->avail_out) n = z->avail_out;
5302 if (n && r == Z_BUF_ERROR) r = Z_OK;
5303
5304 /* update counters */
5305 z->avail_out -= n;
5306 z->total_out += n;
5307
5308 /* update check information */
5309 if (s->checkfn != Z_NULL)
5310 z->adler = s->check = (*s->checkfn)(s->check, q, n);
5311
5312 /* copy as far as end of window */
5313 zmemcpy(p, q, n);
5314 p += n;
5315 q += n;
5316
5317 /* see if more to copy at beginning of window */
5318 if (q == s->end)
5319 {
5320 /* wrap pointers */
5321 q = s->window;
5322 if (s->write == s->end)
5323 s->write = s->window;
5324
5325 /* compute bytes to copy */
5326 n = (uInt)(s->write - 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 */
5339 zmemcpy(p, q, n);
5340 p += n;
5341 q += n;
5342 }
5343
5344 /* update pointers */
5345 z->next_out = p;
5346 s->read = q;
5347
5348 /* done */
5349 return r;
5350 }
5351 /* --- infutil.c */
5352
5353 /* +++ inffast.c */
5354 /* inffast.c -- process literals and length/distance pairs fast
5355 * Copyright (C) 1995-2002 Mark Adler
5356 * For conditions of distribution and use, see copyright notice in zlib.h
5357 */
5358
5359 /* #include "zutil.h" */
5360 /* #include "inftrees.h" */
5361 /* #include "infblock.h" */
5362 /* #include "infcodes.h" */
5363 /* #include "infutil.h" */
5364 /* #include "inffast.h" */
5365
5366 #ifndef NO_DUMMY_DECL
5367 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
5368 #endif
5369
5370 /* simplify the use of the inflate_huft type with some defines */
5371 #define exop word.what.Exop
5372 #define bits word.what.Bits
5373
5374 /* macros for bit input with no checking and for returning unused bytes */
5375 #define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}}
5376 #define UNGRAB {c=z->avail_in-n;c=(k>>3)<c?k>>3:c;n+=c;p-=c;k-=c<<3;}
5377
5378 /* Called with number of bytes left to write in window at least 258
5379 (the maximum string length) and number of input bytes available
5380 at least ten. The ten bytes are six bytes for the longest length/
5381 distance pair plus four bytes for overloading the bit buffer. */
5382
5383 int inflate_fast(bl, bd, tl, td, s, z)
5384 uInt bl, bd;
5385 inflate_huft *tl;
5386 inflate_huft *td; /* need separate declaration for Borland C++ */
5387 inflate_blocks_statef *s;
5388 z_streamp z;
5389 {
5390 inflate_huft *t; /* temporary pointer */
5391 uInt e; /* extra bits or operation */
5392 uLong b; /* bit buffer */
5393 uInt k; /* bits in bit buffer */
5394 Bytef *p; /* input data pointer */
5395 uInt n; /* bytes available there */
5396 Bytef *q; /* output window write pointer */
5397 uInt m; /* bytes to end of window or read pointer */
5398 uInt ml; /* mask for literal/length tree */
5399 uInt md; /* mask for distance tree */
5400 uInt c; /* bytes to copy */
5401 uInt d; /* distance back to copy from */
5402 Bytef *r; /* copy source pointer */
5403
5404 /* load input, output, bit values */
5405 LOAD
5406
5407 /* initialize masks */
5408 ml = inflate_mask[bl];
5409 md = inflate_mask[bd];
5410
5411 /* do until not enough input or output space for fast loop */
5412 do { /* assume called with m >= 258 && n >= 10 */
5413 /* get literal/length code */
5414 GRABBITS(20) /* max bits for literal/length code */
5415 if ((e = (t = tl + ((uInt)b & ml))->exop) == 0)
5416 {
5417 DUMPBITS(t->bits)
5418 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5419 "inflate: * literal '%c'\n" :
5420 "inflate: * literal 0x%02x\n", t->base));
5421 *q++ = (Byte)t->base;
5422 m--;
5423 continue;
5424 }
5425 do {
5426 DUMPBITS(t->bits)
5427 if (e & 16)
5428 {
5429 /* get extra bits for length */
5430 e &= 15;
5431 c = t->base + ((uInt)b & inflate_mask[e]);
5432 DUMPBITS(e)
5433 Tracevv((stderr, "inflate: * length %u\n", c));
5434
5435 /* decode distance base of block to copy */
5436 GRABBITS(15); /* max bits for distance code */
5437 e = (t = td + ((uInt)b & md))->exop;
5438 do {
5439 DUMPBITS(t->bits)
5440 if (e & 16)
5441 {
5442 /* get extra bits to add to distance base */
5443 e &= 15;
5444 GRABBITS(e) /* get extra bits (up to 13) */
5445 d = t->base + ((uInt)b & inflate_mask[e]);
5446 DUMPBITS(e)
5447 Tracevv((stderr, "inflate: * distance %u\n", d));
5448
5449 /* do the copy */
5450 m -= c;
5451 r = q - d;
5452 if (r < s->window) /* wrap if needed */
5453 {
5454 do {
5455 r += s->end - s->window; /* force pointer in window */
5456 } while (r < s->window); /* covers invalid distances */
5457 e = s->end - r;
5458 if (c > e)
5459 {
5460 c -= e; /* wrapped copy */
5461 do {
5462 *q++ = *r++;
5463 } while (--e);
5464 r = s->window;
5465 do {
5466 *q++ = *r++;
5467 } while (--c);
5468 }
5469 else /* normal copy */
5470 {
5471 *q++ = *r++; c--;
5472 *q++ = *r++; c--;
5473 do {
5474 *q++ = *r++;
5475 } while (--c);
5476 }
5477 }
5478 else /* normal copy */
5479 {
5480 *q++ = *r++; c--;
5481 *q++ = *r++; c--;
5482 do {
5483 *q++ = *r++;
5484 } while (--c);
5485 }
5486 break;
5487 }
5488 else if ((e & 64) == 0)
5489 {
5490 t += t->base;
5491 e = (t += ((uInt)b & inflate_mask[e]))->exop;
5492 }
5493 else
5494 {
5495 z->msg = (char*)"invalid distance code";
5496 UNGRAB
5497 UPDATE
5498 return Z_DATA_ERROR;
5499 }
5500 } while (1);
5501 break;
5502 }
5503 if ((e & 64) == 0)
5504 {
5505 t += t->base;
5506 if ((e = (t += ((uInt)b & inflate_mask[e]))->exop) == 0)
5507 {
5508 DUMPBITS(t->bits)
5509 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5510 "inflate: * literal '%c'\n" :
5511 "inflate: * literal 0x%02x\n", t->base));
5512 *q++ = (Byte)t->base;
5513 m--;
5514 break;
5515 }
5516 }
5517 else if (e & 32)
5518 {
5519 Tracevv((stderr, "inflate: * end of block\n"));
5520 UNGRAB
5521 UPDATE
5522 return Z_STREAM_END;
5523 }
5524 else
5525 {
5526 z->msg = (char*)"invalid literal/length code";
5527 UNGRAB
5528 UPDATE
5529 return Z_DATA_ERROR;
5530 }
5531 } while (1);
5532 } while (m >= 258 && n >= 10);
5533
5534 /* not enough input or output--restore pointers and return */
5535 UNGRAB
5536 UPDATE
5537 return Z_OK;
5538 }
5539 /* --- inffast.c */
5540
5541 /* +++ zutil.c */
5542 /* zutil.c -- target dependent utility functions for the compression library
5543 * Copyright (C) 1995-2002 Jean-loup Gailly.
5544 * For conditions of distribution and use, see copyright notice in zlib.h
5545 */
5546
5547 /* @(#) $Id: zlib.c,v 1.9 2002/11/28 00:56:55 lindak Exp $ */
5548
5549 /* #include "zutil.h" */
5550
5551 #ifndef NO_DUMMY_DECL
5552 struct internal_state {int dummy;}; /* for buggy compilers */
5553 #endif
5554
5555 #ifndef STDC
5556 extern void exit OF((int));
5557 #endif
5558
5559 const char *z_errmsg[10] = {
5560 "need dictionary", /* Z_NEED_DICT 2 */
5561 "stream end", /* Z_STREAM_END 1 */
5562 "", /* Z_OK 0 */
5563 "file error", /* Z_ERRNO (-1) */
5564 "stream error", /* Z_STREAM_ERROR (-2) */
5565 "data error", /* Z_DATA_ERROR (-3) */
5566 "insufficient memory", /* Z_MEM_ERROR (-4) */
5567 "buffer error", /* Z_BUF_ERROR (-5) */
5568 "incompatible version",/* Z_VERSION_ERROR (-6) */
5569 ""};
5570
5571
5572 const char * ZEXPORT zlibVersion()
5573 {
5574 return ZLIB_VERSION;
5575 }
5576
5577 #ifdef DEBUG_ZLIB
5578
5579 # ifndef verbose
5580 # define verbose 0
5581 # endif
5582 int z_verbose = verbose;
5583
5584 void z_error (m)
5585 char *m;
5586 {
5587 fprintf(stderr, "%s\n", m);
5588 exit(1);
5589 }
5590 #endif
5591
5592 /* exported to allow conversion of error code to string for compress() and
5593 * uncompress()
5594 */
5595 const char * ZEXPORT zError(err)
5596 int err;
5597 {
5598 return ERR_MSG(err);
5599 }
5600
5601
5602 #ifndef HAVE_MEMCPY
5603
5604 void zmemcpy(dest, source, len)
5605 Bytef* dest;
5606 const Bytef* source;
5607 uInt len;
5608 {
5609 if (len == 0) return;
5610 do {
5611 *dest++ = *source++; /* ??? to be unrolled */
5612 } while (--len != 0);
5613 }
5614
5615 int zmemcmp(s1, s2, len)
5616 const Bytef* s1;
5617 const Bytef* s2;
5618 uInt len;
5619 {
5620 uInt j;
5621
5622 for (j = 0; j < len; j++) {
5623 if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1;
5624 }
5625 return 0;
5626 }
5627
5628 void zmemzero(dest, len)
5629 Bytef* dest;
5630 uInt len;
5631 {
5632 if (len == 0) return;
5633 do {
5634 *dest++ = 0; /* ??? to be unrolled */
5635 } while (--len != 0);
5636 }
5637 #endif
5638
5639 #ifdef __TURBOC__
5640 #if (defined( __BORLANDC__) || !defined(SMALL_MEDIUM)) && !defined(__32BIT__)
5641 /* Small and medium model in Turbo C are for now limited to near allocation
5642 * with reduced MAX_WBITS and MAX_MEM_LEVEL
5643 */
5644 # define MY_ZCALLOC
5645
5646 /* Turbo C malloc() does not allow dynamic allocation of 64K bytes
5647 * and farmalloc(64K) returns a pointer with an offset of 8, so we
5648 * must fix the pointer. Warning: the pointer must be put back to its
5649 * original form in order to free it, use zcfree().
5650 */
5651
5652 #define MAX_PTR 10
5653 /* 10*64K = 640K */
5654
5655 local int next_ptr = 0;
5656
5657 typedef struct ptr_table_s {
5658 voidpf org_ptr;
5659 voidpf new_ptr;
5660 } ptr_table;
5661
5662 local ptr_table table[MAX_PTR];
5663 /* This table is used to remember the original form of pointers
5664 * to large buffers (64K). Such pointers are normalized with a zero offset.
5665 * Since MSDOS is not a preemptive multitasking OS, this table is not
5666 * protected from concurrent access. This hack doesn't work anyway on
5667 * a protected system like OS/2. Use Microsoft C instead.
5668 */
5669
5670 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
5671 {
5672 voidpf buf = opaque; /* just to make some compilers happy */
5673 ulg bsize = (ulg)items*size;
5674
5675 /* If we allocate less than 65520 bytes, we assume that farmalloc
5676 * will return a usable pointer which doesn't have to be normalized.
5677 */
5678 if (bsize < 65520L) {
5679 buf = farmalloc(bsize);
5680 if (*(ush*)&buf != 0) return buf;
5681 } else {
5682 buf = farmalloc(bsize + 16L);
5683 }
5684 if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
5685 table[next_ptr].org_ptr = buf;
5686
5687 /* Normalize the pointer to seg:0 */
5688 *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
5689 *(ush*)&buf = 0;
5690 table[next_ptr++].new_ptr = buf;
5691 return buf;
5692 }
5693
5694 void zcfree (voidpf opaque, voidpf ptr)
5695 {
5696 int n;
5697 if (*(ush*)&ptr != 0) { /* object < 64K */
5698 farfree(ptr);
5699 return;
5700 }
5701 /* Find the original pointer */
5702 for (n = 0; n < next_ptr; n++) {
5703 if (ptr != table[n].new_ptr) continue;
5704
5705 farfree(table[n].org_ptr);
5706 while (++n < next_ptr) {
5707 table[n-1] = table[n];
5708 }
5709 next_ptr--;
5710 return;
5711 }
5712 ptr = opaque; /* just to make some compilers happy */
5713 Assert(0, "zcfree: ptr not found");
5714 }
5715 #endif
5716 #endif /* __TURBOC__ */
5717
5718
5719 #if defined(M_I86) && !defined(__32BIT__)
5720 /* Microsoft C in 16-bit mode */
5721
5722 # define MY_ZCALLOC
5723
5724 #if (!defined(_MSC_VER) || (_MSC_VER <= 600))
5725 # define _halloc halloc
5726 # define _hfree hfree
5727 #endif
5728
5729 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
5730 {
5731 if (opaque) opaque = 0; /* to make compiler happy */
5732 return _halloc((long)items, size);
5733 }
5734
5735 void zcfree (voidpf opaque, voidpf ptr)
5736 {
5737 if (opaque) opaque = 0; /* to make compiler happy */
5738 _hfree(ptr);
5739 }
5740
5741 #endif /* MSC */
5742
5743
5744 #ifndef MY_ZCALLOC /* Any system without a special alloc function */
5745
5746 #ifndef STDC
5747 extern voidp calloc OF((uInt items, uInt size));
5748 extern void free OF((voidpf ptr));
5749 #endif
5750
5751 voidpf zcalloc (opaque, items, size)
5752 voidpf opaque;
5753 unsigned items;
5754 unsigned size;
5755 {
5756 if (opaque) items += size - size; /* make compiler happy */
5757 return (voidpf)calloc(items, size);
5758 }
5759
5760 void zcfree (opaque, ptr)
5761 voidpf opaque;
5762 voidpf ptr;
5763 {
5764 _FREE(ptr);
5765 if (opaque) return; /* make compiler happy */
5766 }
5767
5768 #endif /* MY_ZCALLOC */
5769 /* --- zutil.c */
5770
5771 /* +++ adler32.c */
5772 /* adler32.c -- compute the Adler-32 checksum of a data stream
5773 * Copyright (C) 1995-2002 Mark Adler
5774 * For conditions of distribution and use, see copyright notice in zlib.h
5775 */
5776
5777 /* @(#) $Id: zlib.c,v 1.9 2002/11/28 00:56:55 lindak Exp $ */
5778
5779 /* #include "zlib.h" */
5780
5781 #define BASE 65521L /* largest prime smaller than 65536 */
5782 #define NMAX 5552
5783 /* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
5784
5785 #define DO1(buf,i) {s1 += buf[i]; s2 += s1;}
5786 #define DO2(buf,i) DO1(buf,i); DO1(buf,i+1);
5787 #define DO4(buf,i) DO2(buf,i); DO2(buf,i+2);
5788 #define DO8(buf,i) DO4(buf,i); DO4(buf,i+4);
5789 #define DO16(buf) DO8(buf,0); DO8(buf,8);
5790
5791 /* ========================================================================= */
5792 uLong ZEXPORT adler32(adler, buf, len)
5793 uLong adler;
5794 const Bytef *buf;
5795 uInt len;
5796 {
5797 unsigned long s1 = adler & 0xffff;
5798 unsigned long s2 = (adler >> 16) & 0xffff;
5799 int k;
5800
5801 if (buf == Z_NULL) return 1L;
5802
5803 while (len > 0) {
5804 k = len < NMAX ? len : NMAX;
5805 len -= k;
5806 while (k >= 16) {
5807 DO16(buf);
5808 buf += 16;
5809 k -= 16;
5810 }
5811 if (k != 0) do {
5812 s1 += *buf++;
5813 s2 += s1;
5814 } while (--k);
5815 s1 %= BASE;
5816 s2 %= BASE;
5817 }
5818 return (s2 << 16) | s1;
5819 }
5820 /* --- adler32.c */