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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 1.8 2002/03/29 03:16:07 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 1.8 2002/03/29 03:16:07 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 1.8 2002/03/29 03:16:07 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 1.8 2002/03/29 03:16:07 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[L_CODES+2];
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[D_CODES];
2069 /* The static distance tree. (Actually a trivial tree since all codes use
2070 * 5 bits.)
2071 */
2072
2073 uch _dist_code[DIST_CODE_LEN];
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[MAX_MATCH-MIN_MATCH+1];
2080 /* length code for each normalized match length (0 == MIN_MATCH) */
2081
2082 local int base_length[LENGTH_CODES];
2083 /* First normalized length for each code (0 = MIN_MATCH) */
2084
2085 local int base_dist[D_CODES];
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 {static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS};
2231
2232 local static_tree_desc static_d_desc =
2233 {static_dtree, extra_dbits, 0, D_CODES, MAX_BITS};
2234
2235 local static_tree_desc static_bl_desc =
2236 {(const ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS};
2237
2238 /* ===========================================================================
2239 * Local (static) routines in this file.
2240 */
2241
2242 local void tr_static_init OF((void));
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 /* ===========================================================================
2339 * Initialize the various 'constant' tables.
2340 */
2341 local void tr_static_init()
2342 {
2343 #if defined(GEN_TREES_H) || !defined(STDC)
2344 static int static_init_done = 0;
2345 int n; /* iterates over tree elements */
2346 int bits; /* bit counter */
2347 int length; /* length value */
2348 int code; /* code value */
2349 int dist; /* distance index */
2350 ush bl_count[MAX_BITS+1];
2351 /* number of codes at each bit length for an optimal tree */
2352
2353 if (static_init_done) return;
2354
2355 /* For some embedded targets, global variables are not initialized: */
2356 static_l_desc.static_tree = static_ltree;
2357 static_l_desc.extra_bits = extra_lbits;
2358 static_d_desc.static_tree = static_dtree;
2359 static_d_desc.extra_bits = extra_dbits;
2360 static_bl_desc.extra_bits = extra_blbits;
2361
2362 /* Initialize the mapping length (0..255) -> length code (0..28) */
2363 length = 0;
2364 for (code = 0; code < LENGTH_CODES-1; code++) {
2365 base_length[code] = length;
2366 for (n = 0; n < (1<<extra_lbits[code]); n++) {
2367 _length_code[length++] = (uch)code;
2368 }
2369 }
2370 Assert (length == 256, "tr_static_init: length != 256");
2371 /* Note that the length 255 (match length 258) can be represented
2372 * in two different ways: code 284 + 5 bits or code 285, so we
2373 * overwrite length_code[255] to use the best encoding:
2374 */
2375 _length_code[length-1] = (uch)code;
2376
2377 /* Initialize the mapping dist (0..32K) -> dist code (0..29) */
2378 dist = 0;
2379 for (code = 0 ; code < 16; code++) {
2380 base_dist[code] = dist;
2381 for (n = 0; n < (1<<extra_dbits[code]); n++) {
2382 _dist_code[dist++] = (uch)code;
2383 }
2384 }
2385 Assert (dist == 256, "tr_static_init: dist != 256");
2386 dist >>= 7; /* from now on, all distances are divided by 128 */
2387 for ( ; code < D_CODES; code++) {
2388 base_dist[code] = dist << 7;
2389 for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) {
2390 _dist_code[256 + dist++] = (uch)code;
2391 }
2392 }
2393 Assert (dist == 256, "tr_static_init: 256+dist != 512");
2394
2395 /* Construct the codes of the static literal tree */
2396 for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
2397 n = 0;
2398 while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++;
2399 while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++;
2400 while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++;
2401 while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++;
2402 /* Codes 286 and 287 do not exist, but we must include them in the
2403 * tree construction to get a canonical Huffman tree (longest code
2404 * all ones)
2405 */
2406 gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count);
2407
2408 /* The static distance tree is trivial: */
2409 for (n = 0; n < D_CODES; n++) {
2410 static_dtree[n].Len = 5;
2411 static_dtree[n].Code = bi_reverse((unsigned)n, 5);
2412 }
2413 static_init_done = 1;
2414
2415 # ifdef GEN_TREES_H
2416 gen_trees_header();
2417 # endif
2418 #endif /* defined(GEN_TREES_H) || !defined(STDC) */
2419 }
2420
2421 /* ===========================================================================
2422 * Genererate the file trees.h describing the static trees.
2423 */
2424 #ifdef GEN_TREES_H
2425 # ifndef DEBUG_ZLIB
2426 # include <stdio.h>
2427 # endif
2428
2429 # define SEPARATOR(i, last, width) \
2430 ((i) == (last)? "\n};\n\n" : \
2431 ((i) % (width) == (width)-1 ? ",\n" : ", "))
2432
2433 void gen_trees_header()
2434 {
2435 FILE *header = fopen("trees.h", "w");
2436 int i;
2437
2438 Assert (header != NULL, "Can't open trees.h");
2439 fprintf(header,
2440 "/* header created automatically with -DGEN_TREES_H */\n\n");
2441
2442 fprintf(header, "local const ct_data static_ltree[L_CODES+2] = {\n");
2443 for (i = 0; i < L_CODES+2; i++) {
2444 fprintf(header, "{{%3u},{%3u}}%s", static_ltree[i].Code,
2445 static_ltree[i].Len, SEPARATOR(i, L_CODES+1, 5));
2446 }
2447
2448 fprintf(header, "local const ct_data static_dtree[D_CODES] = {\n");
2449 for (i = 0; i < D_CODES; i++) {
2450 fprintf(header, "{{%2u},{%2u}}%s", static_dtree[i].Code,
2451 static_dtree[i].Len, SEPARATOR(i, D_CODES-1, 5));
2452 }
2453
2454 fprintf(header, "const uch _dist_code[DIST_CODE_LEN] = {\n");
2455 for (i = 0; i < DIST_CODE_LEN; i++) {
2456 fprintf(header, "%2u%s", _dist_code[i],
2457 SEPARATOR(i, DIST_CODE_LEN-1, 20));
2458 }
2459
2460 fprintf(header, "const uch _length_code[MAX_MATCH-MIN_MATCH+1]= {\n");
2461 for (i = 0; i < MAX_MATCH-MIN_MATCH+1; i++) {
2462 fprintf(header, "%2u%s", _length_code[i],
2463 SEPARATOR(i, MAX_MATCH-MIN_MATCH, 20));
2464 }
2465
2466 fprintf(header, "local const int base_length[LENGTH_CODES] = {\n");
2467 for (i = 0; i < LENGTH_CODES; i++) {
2468 fprintf(header, "%1u%s", base_length[i],
2469 SEPARATOR(i, LENGTH_CODES-1, 20));
2470 }
2471
2472 fprintf(header, "local const int base_dist[D_CODES] = {\n");
2473 for (i = 0; i < D_CODES; i++) {
2474 fprintf(header, "%5u%s", base_dist[i],
2475 SEPARATOR(i, D_CODES-1, 10));
2476 }
2477
2478 fclose(header);
2479 }
2480 #endif /* GEN_TREES_H */
2481
2482 /* ===========================================================================
2483 * Initialize the tree data structures for a new zlib stream.
2484 */
2485 void _tr_init(s)
2486 deflate_state *s;
2487 {
2488 tr_static_init();
2489
2490 s->l_desc.dyn_tree = s->dyn_ltree;
2491 s->l_desc.stat_desc = &static_l_desc;
2492
2493 s->d_desc.dyn_tree = s->dyn_dtree;
2494 s->d_desc.stat_desc = &static_d_desc;
2495
2496 s->bl_desc.dyn_tree = s->bl_tree;
2497 s->bl_desc.stat_desc = &static_bl_desc;
2498
2499 s->bi_buf = 0;
2500 s->bi_valid = 0;
2501 s->last_eob_len = 8; /* enough lookahead for inflate */
2502 #ifdef DEBUG_ZLIB
2503 s->compressed_len = 0L;
2504 s->bits_sent = 0L;
2505 #endif
2506
2507 /* Initialize the first block of the first file: */
2508 init_block(s);
2509 }
2510
2511 /* ===========================================================================
2512 * Initialize a new block.
2513 */
2514 local void init_block(s)
2515 deflate_state *s;
2516 {
2517 int n; /* iterates over tree elements */
2518
2519 /* Initialize the trees. */
2520 for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0;
2521 for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0;
2522 for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0;
2523
2524 s->dyn_ltree[END_BLOCK].Freq = 1;
2525 s->opt_len = s->static_len = 0L;
2526 s->last_lit = s->matches = 0;
2527 }
2528
2529 #define SMALLEST 1
2530 /* Index within the heap array of least frequent node in the Huffman tree */
2531
2532
2533 /* ===========================================================================
2534 * Remove the smallest element from the heap and recreate the heap with
2535 * one less element. Updates heap and heap_len.
2536 */
2537 #define pqremove(s, tree, top) \
2538 {\
2539 top = s->heap[SMALLEST]; \
2540 s->heap[SMALLEST] = s->heap[s->heap_len--]; \
2541 pqdownheap(s, tree, SMALLEST); \
2542 }
2543
2544 /* ===========================================================================
2545 * Compares to subtrees, using the tree depth as tie breaker when
2546 * the subtrees have equal frequency. This minimizes the worst case length.
2547 */
2548 #define smaller(tree, n, m, depth) \
2549 (tree[n].Freq < tree[m].Freq || \
2550 (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m]))
2551
2552 /* ===========================================================================
2553 * Restore the heap property by moving down the tree starting at node k,
2554 * exchanging a node with the smallest of its two sons if necessary, stopping
2555 * when the heap property is re-established (each father smaller than its
2556 * two sons).
2557 */
2558 local void pqdownheap(s, tree, k)
2559 deflate_state *s;
2560 ct_data *tree; /* the tree to restore */
2561 int k; /* node to move down */
2562 {
2563 int v = s->heap[k];
2564 int j = k << 1; /* left son of k */
2565 while (j <= s->heap_len) {
2566 /* Set j to the smallest of the two sons: */
2567 if (j < s->heap_len &&
2568 smaller(tree, s->heap[j+1], s->heap[j], s->depth)) {
2569 j++;
2570 }
2571 /* Exit if v is smaller than both sons */
2572 if (smaller(tree, v, s->heap[j], s->depth)) break;
2573
2574 /* Exchange v with the smallest son */
2575 s->heap[k] = s->heap[j]; k = j;
2576
2577 /* And continue down the tree, setting j to the left son of k */
2578 j <<= 1;
2579 }
2580 s->heap[k] = v;
2581 }
2582
2583 /* ===========================================================================
2584 * Compute the optimal bit lengths for a tree and update the total bit length
2585 * for the current block.
2586 * IN assertion: the fields freq and dad are set, heap[heap_max] and
2587 * above are the tree nodes sorted by increasing frequency.
2588 * OUT assertions: the field len is set to the optimal bit length, the
2589 * array bl_count contains the frequencies for each bit length.
2590 * The length opt_len is updated; static_len is also updated if stree is
2591 * not null.
2592 */
2593 local void gen_bitlen(s, desc)
2594 deflate_state *s;
2595 tree_desc *desc; /* the tree descriptor */
2596 {
2597 ct_data *tree = desc->dyn_tree;
2598 int max_code = desc->max_code;
2599 const ct_data *stree = desc->stat_desc->static_tree;
2600 const intf *extra = desc->stat_desc->extra_bits;
2601 int base = desc->stat_desc->extra_base;
2602 int max_length = desc->stat_desc->max_length;
2603 int h; /* heap index */
2604 int n, m; /* iterate over the tree elements */
2605 int bits; /* bit length */
2606 int xbits; /* extra bits */
2607 ush f; /* frequency */
2608 int overflow = 0; /* number of elements with bit length too large */
2609
2610 for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0;
2611
2612 /* In a first pass, compute the optimal bit lengths (which may
2613 * overflow in the case of the bit length tree).
2614 */
2615 tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */
2616
2617 for (h = s->heap_max+1; h < HEAP_SIZE; h++) {
2618 n = s->heap[h];
2619 bits = tree[tree[n].Dad].Len + 1;
2620 if (bits > max_length) bits = max_length, overflow++;
2621 tree[n].Len = (ush)bits;
2622 /* We overwrite tree[n].Dad which is no longer needed */
2623
2624 if (n > max_code) continue; /* not a leaf node */
2625
2626 s->bl_count[bits]++;
2627 xbits = 0;
2628 if (n >= base) xbits = extra[n-base];
2629 f = tree[n].Freq;
2630 s->opt_len += (ulg)f * (bits + xbits);
2631 if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits);
2632 }
2633 if (overflow == 0) return;
2634
2635 Trace((stderr,"\nbit length overflow\n"));
2636 /* This happens for example on obj2 and pic of the Calgary corpus */
2637
2638 /* Find the first bit length which could increase: */
2639 do {
2640 bits = max_length-1;
2641 while (s->bl_count[bits] == 0) bits--;
2642 s->bl_count[bits]--; /* move one leaf down the tree */
2643 s->bl_count[bits+1] += 2; /* move one overflow item as its brother */
2644 s->bl_count[max_length]--;
2645 /* The brother of the overflow item also moves one step up,
2646 * but this does not affect bl_count[max_length]
2647 */
2648 overflow -= 2;
2649 } while (overflow > 0);
2650
2651 /* Now recompute all bit lengths, scanning in increasing frequency.
2652 * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
2653 * lengths instead of fixing only the wrong ones. This idea is taken
2654 * from 'ar' written by Haruhiko Okumura.)
2655 */
2656 for (bits = max_length; bits != 0; bits--) {
2657 n = s->bl_count[bits];
2658 while (n != 0) {
2659 m = s->heap[--h];
2660 if (m > max_code) continue;
2661 if (tree[m].Len != (unsigned) bits) {
2662 Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits));
2663 s->opt_len += ((long)bits - (long)tree[m].Len)
2664 *(long)tree[m].Freq;
2665 tree[m].Len = (ush)bits;
2666 }
2667 n--;
2668 }
2669 }
2670 }
2671
2672 /* ===========================================================================
2673 * Generate the codes for a given tree and bit counts (which need not be
2674 * optimal).
2675 * IN assertion: the array bl_count contains the bit length statistics for
2676 * the given tree and the field len is set for all tree elements.
2677 * OUT assertion: the field code is set for all tree elements of non
2678 * zero code length.
2679 */
2680 local void gen_codes (tree, max_code, bl_count)
2681 ct_data *tree; /* the tree to decorate */
2682 int max_code; /* largest code with non zero frequency */
2683 ushf *bl_count; /* number of codes at each bit length */
2684 {
2685 ush next_code[MAX_BITS+1]; /* next code value for each bit length */
2686 ush code = 0; /* running code value */
2687 int bits; /* bit index */
2688 int n; /* code index */
2689
2690 /* The distribution counts are first used to generate the code values
2691 * without bit reversal.
2692 */
2693 for (bits = 1; bits <= MAX_BITS; bits++) {
2694 next_code[bits] = code = (code + bl_count[bits-1]) << 1;
2695 }
2696 /* Check that the bit counts in bl_count are consistent. The last code
2697 * must be all ones.
2698 */
2699 Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1,
2700 "inconsistent bit counts");
2701 Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
2702
2703 for (n = 0; n <= max_code; n++) {
2704 int len = tree[n].Len;
2705 if (len == 0) continue;
2706 /* Now reverse the bits */
2707 tree[n].Code = bi_reverse(next_code[len]++, len);
2708
2709 Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
2710 n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1));
2711 }
2712 }
2713
2714 /* ===========================================================================
2715 * Construct one Huffman tree and assigns the code bit strings and lengths.
2716 * Update the total bit length for the current block.
2717 * IN assertion: the field freq is set for all tree elements.
2718 * OUT assertions: the fields len and code are set to the optimal bit length
2719 * and corresponding code. The length opt_len is updated; static_len is
2720 * also updated if stree is not null. The field max_code is set.
2721 */
2722 local void build_tree(s, desc)
2723 deflate_state *s;
2724 tree_desc *desc; /* the tree descriptor */
2725 {
2726 ct_data *tree = desc->dyn_tree;
2727 const ct_data *stree = desc->stat_desc->static_tree;
2728 int elems = desc->stat_desc->elems;
2729 int n, m; /* iterate over heap elements */
2730 int max_code = -1; /* largest code with non zero frequency */
2731 int node; /* new node being created */
2732
2733 /* Construct the initial heap, with least frequent element in
2734 * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
2735 * heap[0] is not used.
2736 */
2737 s->heap_len = 0, s->heap_max = HEAP_SIZE;
2738
2739 for (n = 0; n < elems; n++) {
2740 if (tree[n].Freq != 0) {
2741 s->heap[++(s->heap_len)] = max_code = n;
2742 s->depth[n] = 0;
2743 } else {
2744 tree[n].Len = 0;
2745 }
2746 }
2747
2748 /* The pkzip format requires that at least one distance code exists,
2749 * and that at least one bit should be sent even if there is only one
2750 * possible code. So to avoid special checks later on we force at least
2751 * two codes of non zero frequency.
2752 */
2753 while (s->heap_len < 2) {
2754 node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0);
2755 tree[node].Freq = 1;
2756 s->depth[node] = 0;
2757 s->opt_len--; if (stree) s->static_len -= stree[node].Len;
2758 /* node is 0 or 1 so it does not have extra bits */
2759 }
2760 desc->max_code = max_code;
2761
2762 /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
2763 * establish sub-heaps of increasing lengths:
2764 */
2765 for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n);
2766
2767 /* Construct the Huffman tree by repeatedly combining the least two
2768 * frequent nodes.
2769 */
2770 node = elems; /* next internal node of the tree */
2771 do {
2772 pqremove(s, tree, n); /* n = node of least frequency */
2773 m = s->heap[SMALLEST]; /* m = node of next least frequency */
2774
2775 s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */
2776 s->heap[--(s->heap_max)] = m;
2777
2778 /* Create a new node father of n and m */
2779 tree[node].Freq = tree[n].Freq + tree[m].Freq;
2780 s->depth[node] = (uch) (MAX(s->depth[n], s->depth[m]) + 1);
2781 tree[n].Dad = tree[m].Dad = (ush)node;
2782 #ifdef DUMP_BL_TREE
2783 if (tree == s->bl_tree) {
2784 fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)",
2785 node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq);
2786 }
2787 #endif
2788 /* and insert the new node in the heap */
2789 s->heap[SMALLEST] = node++;
2790 pqdownheap(s, tree, SMALLEST);
2791
2792 } while (s->heap_len >= 2);
2793
2794 s->heap[--(s->heap_max)] = s->heap[SMALLEST];
2795
2796 /* At this point, the fields freq and dad are set. We can now
2797 * generate the bit lengths.
2798 */
2799 gen_bitlen(s, (tree_desc *)desc);
2800
2801 /* The field len is now set, we can generate the bit codes */
2802 gen_codes ((ct_data *)tree, max_code, s->bl_count);
2803 }
2804
2805 /* ===========================================================================
2806 * Scan a literal or distance tree to determine the frequencies of the codes
2807 * in the bit length tree.
2808 */
2809 local void scan_tree (s, tree, max_code)
2810 deflate_state *s;
2811 ct_data *tree; /* the tree to be scanned */
2812 int max_code; /* and its largest code of non zero frequency */
2813 {
2814 int n; /* iterates over all tree elements */
2815 int prevlen = -1; /* last emitted length */
2816 int curlen; /* length of current code */
2817 int nextlen = tree[0].Len; /* length of next code */
2818 int count = 0; /* repeat count of the current code */
2819 int max_count = 7; /* max repeat count */
2820 int min_count = 4; /* min repeat count */
2821
2822 if (nextlen == 0) max_count = 138, min_count = 3;
2823 tree[max_code+1].Len = (ush)0xffff; /* guard */
2824
2825 for (n = 0; n <= max_code; n++) {
2826 curlen = nextlen; nextlen = tree[n+1].Len;
2827 if (++count < max_count && curlen == nextlen) {
2828 continue;
2829 } else if (count < min_count) {
2830 s->bl_tree[curlen].Freq += count;
2831 } else if (curlen != 0) {
2832 if (curlen != prevlen) s->bl_tree[curlen].Freq++;
2833 s->bl_tree[REP_3_6].Freq++;
2834 } else if (count <= 10) {
2835 s->bl_tree[REPZ_3_10].Freq++;
2836 } else {
2837 s->bl_tree[REPZ_11_138].Freq++;
2838 }
2839 count = 0; prevlen = curlen;
2840 if (nextlen == 0) {
2841 max_count = 138, min_count = 3;
2842 } else if (curlen == nextlen) {
2843 max_count = 6, min_count = 3;
2844 } else {
2845 max_count = 7, min_count = 4;
2846 }
2847 }
2848 }
2849
2850 /* ===========================================================================
2851 * Send a literal or distance tree in compressed form, using the codes in
2852 * bl_tree.
2853 */
2854 local void send_tree (s, tree, max_code)
2855 deflate_state *s;
2856 ct_data *tree; /* the tree to be scanned */
2857 int max_code; /* and its largest code of non zero frequency */
2858 {
2859 int n; /* iterates over all tree elements */
2860 int prevlen = -1; /* last emitted length */
2861 int curlen; /* length of current code */
2862 int nextlen = tree[0].Len; /* length of next code */
2863 int count = 0; /* repeat count of the current code */
2864 int max_count = 7; /* max repeat count */
2865 int min_count = 4; /* min repeat count */
2866
2867 /* tree[max_code+1].Len = -1; */ /* guard already set */
2868 if (nextlen == 0) max_count = 138, min_count = 3;
2869
2870 for (n = 0; n <= max_code; n++) {
2871 curlen = nextlen; nextlen = tree[n+1].Len;
2872 if (++count < max_count && curlen == nextlen) {
2873 continue;
2874 } else if (count < min_count) {
2875 do { send_code(s, curlen, s->bl_tree); } while (--count != 0);
2876
2877 } else if (curlen != 0) {
2878 if (curlen != prevlen) {
2879 send_code(s, curlen, s->bl_tree); count--;
2880 }
2881 Assert(count >= 3 && count <= 6, " 3_6?");
2882 send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2);
2883
2884 } else if (count <= 10) {
2885 send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3);
2886
2887 } else {
2888 send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7);
2889 }
2890 count = 0; prevlen = curlen;
2891 if (nextlen == 0) {
2892 max_count = 138, min_count = 3;
2893 } else if (curlen == nextlen) {
2894 max_count = 6, min_count = 3;
2895 } else {
2896 max_count = 7, min_count = 4;
2897 }
2898 }
2899 }
2900
2901 /* ===========================================================================
2902 * Construct the Huffman tree for the bit lengths and return the index in
2903 * bl_order of the last bit length code to send.
2904 */
2905 local int build_bl_tree(s)
2906 deflate_state *s;
2907 {
2908 int max_blindex; /* index of last bit length code of non zero freq */
2909
2910 /* Determine the bit length frequencies for literal and distance trees */
2911 scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code);
2912 scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code);
2913
2914 /* Build the bit length tree: */
2915 build_tree(s, (tree_desc *)(&(s->bl_desc)));
2916 /* opt_len now includes the length of the tree representations, except
2917 * the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
2918 */
2919
2920 /* Determine the number of bit length codes to send. The pkzip format
2921 * requires that at least 4 bit length codes be sent. (appnote.txt says
2922 * 3 but the actual value used is 4.)
2923 */
2924 for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) {
2925 if (s->bl_tree[bl_order[max_blindex]].Len != 0) break;
2926 }
2927 /* Update opt_len to include the bit length tree and counts */
2928 s->opt_len += 3*(max_blindex+1) + 5+5+4;
2929 Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld",
2930 s->opt_len, s->static_len));
2931
2932 return max_blindex;
2933 }
2934
2935 /* ===========================================================================
2936 * Send the header for a block using dynamic Huffman trees: the counts, the
2937 * lengths of the bit length codes, the literal tree and the distance tree.
2938 * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
2939 */
2940 local void send_all_trees(s, lcodes, dcodes, blcodes)
2941 deflate_state *s;
2942 int lcodes, dcodes, blcodes; /* number of codes for each tree */
2943 {
2944 int rank; /* index in bl_order */
2945
2946 Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
2947 Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
2948 "too many codes");
2949 Tracev((stderr, "\nbl counts: "));
2950 send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */
2951 send_bits(s, dcodes-1, 5);
2952 send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */
2953 for (rank = 0; rank < blcodes; rank++) {
2954 Tracev((stderr, "\nbl code %2d ", bl_order[rank]));
2955 send_bits(s, s->bl_tree[bl_order[rank]].Len, 3);
2956 }
2957 Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent));
2958
2959 send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */
2960 Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent));
2961
2962 send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */
2963 Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent));
2964 }
2965
2966 /* ===========================================================================
2967 * Send a stored block
2968 */
2969 void _tr_stored_block(s, buf, stored_len, eof)
2970 deflate_state *s;
2971 charf *buf; /* input block */
2972 ulg stored_len; /* length of input block */
2973 int eof; /* true if this is the last block for a file */
2974 {
2975 send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */
2976 #ifdef DEBUG_ZLIB
2977 s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L;
2978 s->compressed_len += (stored_len + 4) << 3;
2979 #endif
2980 copy_block(s, buf, (unsigned)stored_len, 1); /* with header */
2981 }
2982
2983 /* ===========================================================================
2984 * Send one empty static block to give enough lookahead for inflate.
2985 * This takes 10 bits, of which 7 may remain in the bit buffer.
2986 * The current inflate code requires 9 bits of lookahead. If the
2987 * last two codes for the previous block (real code plus EOB) were coded
2988 * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode
2989 * the last real code. In this case we send two empty static blocks instead
2990 * of one. (There are no problems if the previous block is stored or fixed.)
2991 * To simplify the code, we assume the worst case of last real code encoded
2992 * on one bit only.
2993 */
2994 void _tr_align(s)
2995 deflate_state *s;
2996 {
2997 send_bits(s, STATIC_TREES<<1, 3);
2998 send_code(s, END_BLOCK, static_ltree);
2999 #ifdef DEBUG_ZLIB
3000 s->compressed_len += 10L; /* 3 for block type, 7 for EOB */
3001 #endif
3002 bi_flush(s);
3003 /* Of the 10 bits for the empty block, we have already sent
3004 * (10 - bi_valid) bits. The lookahead for the last real code (before
3005 * the EOB of the previous block) was thus at least one plus the length
3006 * of the EOB plus what we have just sent of the empty static block.
3007 */
3008 if (1 + s->last_eob_len + 10 - s->bi_valid < 9) {
3009 send_bits(s, STATIC_TREES<<1, 3);
3010 send_code(s, END_BLOCK, static_ltree);
3011 #ifdef DEBUG_ZLIB
3012 s->compressed_len += 10L;
3013 #endif
3014 bi_flush(s);
3015 }
3016 s->last_eob_len = 7;
3017 }
3018
3019 /* ===========================================================================
3020 * Determine the best encoding for the current block: dynamic trees, static
3021 * trees or store, and output the encoded block to the zip file.
3022 */
3023 void _tr_flush_block(s, buf, stored_len, eof)
3024 deflate_state *s;
3025 charf *buf; /* input block, or NULL if too old */
3026 ulg stored_len; /* length of input block */
3027 int eof; /* true if this is the last block for a file */
3028 {
3029 ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
3030 int max_blindex = 0; /* index of last bit length code of non zero freq */
3031
3032 /* Build the Huffman trees unless a stored block is forced */
3033 if (s->level > 0) {
3034
3035 /* Check if the file is ascii or binary */
3036 if (s->data_type == Z_UNKNOWN) set_data_type(s);
3037
3038 /* Construct the literal and distance trees */
3039 build_tree(s, (tree_desc *)(&(s->l_desc)));
3040 Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len,
3041 s->static_len));
3042
3043 build_tree(s, (tree_desc *)(&(s->d_desc)));
3044 Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len,
3045 s->static_len));
3046 /* At this point, opt_len and static_len are the total bit lengths of
3047 * the compressed block data, excluding the tree representations.
3048 */
3049
3050 /* Build the bit length tree for the above two trees, and get the index
3051 * in bl_order of the last bit length code to send.
3052 */
3053 max_blindex = build_bl_tree(s);
3054
3055 /* Determine the best encoding. Compute first the block length in bytes*/
3056 opt_lenb = (s->opt_len+3+7)>>3;
3057 static_lenb = (s->static_len+3+7)>>3;
3058
3059 Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
3060 opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
3061 s->last_lit));
3062
3063 if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
3064
3065 } else {
3066 Assert(buf != (char*)0, "lost buf");
3067 opt_lenb = static_lenb = stored_len + 5; /* force a stored block */
3068 }
3069
3070 #ifdef FORCE_STORED
3071 if (buf != (char*)0) { /* force stored block */
3072 #else
3073 if (stored_len+4 <= opt_lenb && buf != (char*)0) {
3074 /* 4: two words for the lengths */
3075 #endif
3076 /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
3077 * Otherwise we can't have processed more than WSIZE input bytes since
3078 * the last block flush, because compression would have been
3079 * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
3080 * transform a block into a stored block.
3081 */
3082 _tr_stored_block(s, buf, stored_len, eof);
3083
3084 #ifdef FORCE_STATIC
3085 } else if (static_lenb >= 0) { /* force static trees */
3086 #else
3087 } else if (static_lenb == opt_lenb) {
3088 #endif
3089 send_bits(s, (STATIC_TREES<<1)+eof, 3);
3090 compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree);
3091 #ifdef DEBUG_ZLIB
3092 s->compressed_len += 3 + s->static_len;
3093 #endif
3094 } else {
3095 send_bits(s, (DYN_TREES<<1)+eof, 3);
3096 send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1,
3097 max_blindex+1);
3098 compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree);
3099 #ifdef DEBUG_ZLIB
3100 s->compressed_len += 3 + s->opt_len;
3101 #endif
3102 }
3103 Assert (s->compressed_len == s->bits_sent, "bad compressed size");
3104 /* The above check is made mod 2^32, for files larger than 512 MB
3105 * and uLong implemented on 32 bits.
3106 */
3107 init_block(s);
3108
3109 if (eof) {
3110 bi_windup(s);
3111 #ifdef DEBUG_ZLIB
3112 s->compressed_len += 7; /* align on byte boundary */
3113 #endif
3114 }
3115 Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3,
3116 s->compressed_len-7*eof));
3117 }
3118
3119 /* ===========================================================================
3120 * Save the match info and tally the frequency counts. Return true if
3121 * the current block must be flushed.
3122 */
3123 int _tr_tally (s, dist, lc)
3124 deflate_state *s;
3125 unsigned dist; /* distance of matched string */
3126 unsigned lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */
3127 {
3128 s->d_buf[s->last_lit] = (ush)dist;
3129 s->l_buf[s->last_lit++] = (uch)lc;
3130 if (dist == 0) {
3131 /* lc is the unmatched char */
3132 s->dyn_ltree[lc].Freq++;
3133 } else {
3134 s->matches++;
3135 /* Here, lc is the match length - MIN_MATCH */
3136 dist--; /* dist = match distance - 1 */
3137 Assert((ush)dist < (ush)MAX_DIST(s) &&
3138 (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
3139 (ush)d_code(dist) < (ush)D_CODES, "_tr_tally: bad match");
3140
3141 s->dyn_ltree[_length_code[lc]+LITERALS+1].Freq++;
3142 s->dyn_dtree[d_code(dist)].Freq++;
3143 }
3144
3145 #ifdef TRUNCATE_BLOCK
3146 /* Try to guess if it is profitable to stop the current block here */
3147 if ((s->last_lit & 0x1fff) == 0 && s->level > 2) {
3148 /* Compute an upper bound for the compressed length */
3149 ulg out_length = (ulg)s->last_lit*8L;
3150 ulg in_length = (ulg)((long)s->strstart - s->block_start);
3151 int dcode;
3152 for (dcode = 0; dcode < D_CODES; dcode++) {
3153 out_length += (ulg)s->dyn_dtree[dcode].Freq *
3154 (5L+extra_dbits[dcode]);
3155 }
3156 out_length >>= 3;
3157 Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ",
3158 s->last_lit, in_length, out_length,
3159 100L - out_length*100L/in_length));
3160 if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1;
3161 }
3162 #endif
3163 return (s->last_lit == s->lit_bufsize-1);
3164 /* We avoid equality with lit_bufsize because of wraparound at 64K
3165 * on 16 bit machines and because stored blocks are restricted to
3166 * 64K-1 bytes.
3167 */
3168 }
3169
3170 /* ===========================================================================
3171 * Send the block data compressed using the given Huffman trees
3172 */
3173 local void compress_block(s, ltree, dtree)
3174 deflate_state *s;
3175 ct_data *ltree; /* literal tree */
3176 ct_data *dtree; /* distance tree */
3177 {
3178 unsigned dist; /* distance of matched string */
3179 int lc; /* match length or unmatched char (if dist == 0) */
3180 unsigned lx = 0; /* running index in l_buf */
3181 unsigned code; /* the code to send */
3182 int extra; /* number of extra bits to send */
3183
3184 if (s->last_lit != 0) do {
3185 dist = s->d_buf[lx];
3186 lc = s->l_buf[lx++];
3187 if (dist == 0) {
3188 send_code(s, lc, ltree); /* send a literal byte */
3189 Tracecv(isgraph(lc), (stderr," '%c' ", lc));
3190 } else {
3191 /* Here, lc is the match length - MIN_MATCH */
3192 code = _length_code[lc];
3193 send_code(s, code+LITERALS+1, ltree); /* send the length code */
3194 extra = extra_lbits[code];
3195 if (extra != 0) {
3196 lc -= base_length[code];
3197 send_bits(s, lc, extra); /* send the extra length bits */
3198 }
3199 dist--; /* dist is now the match distance - 1 */
3200 code = d_code(dist);
3201 Assert (code < D_CODES, "bad d_code");
3202
3203 send_code(s, code, dtree); /* send the distance code */
3204 extra = extra_dbits[code];
3205 if (extra != 0) {
3206 dist -= base_dist[code];
3207 send_bits(s, dist, extra); /* send the extra distance bits */
3208 }
3209 } /* literal or match pair ? */
3210
3211 /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */
3212 Assert(s->pending < s->lit_bufsize + 2*lx, "pendingBuf overflow");
3213
3214 } while (lx < s->last_lit);
3215
3216 send_code(s, END_BLOCK, ltree);
3217 s->last_eob_len = ltree[END_BLOCK].Len;
3218 }
3219
3220 /* ===========================================================================
3221 * Set the data type to ASCII or BINARY, using a crude approximation:
3222 * binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise.
3223 * IN assertion: the fields freq of dyn_ltree are set and the total of all
3224 * frequencies does not exceed 64K (to fit in an int on 16 bit machines).
3225 */
3226 local void set_data_type(s)
3227 deflate_state *s;
3228 {
3229 int n = 0;
3230 unsigned ascii_freq = 0;
3231 unsigned bin_freq = 0;
3232 while (n < 7) bin_freq += s->dyn_ltree[n++].Freq;
3233 while (n < 128) ascii_freq += s->dyn_ltree[n++].Freq;
3234 while (n < LITERALS) bin_freq += s->dyn_ltree[n++].Freq;
3235 s->data_type = (Byte)(bin_freq > (ascii_freq >> 2) ? Z_BINARY : Z_ASCII);
3236 }
3237
3238 /* ===========================================================================
3239 * Reverse the first len bits of a code, using straightforward code (a faster
3240 * method would use a table)
3241 * IN assertion: 1 <= len <= 15
3242 */
3243 local unsigned bi_reverse(code, len)
3244 unsigned code; /* the value to invert */
3245 int len; /* its bit length */
3246 {
3247 register unsigned res = 0;
3248 do {
3249 res |= code & 1;
3250 code >>= 1, res <<= 1;
3251 } while (--len > 0);
3252 return res >> 1;
3253 }
3254
3255 /* ===========================================================================
3256 * Flush the bit buffer, keeping at most 7 bits in it.
3257 */
3258 local void bi_flush(s)
3259 deflate_state *s;
3260 {
3261 if (s->bi_valid == 16) {
3262 put_short(s, s->bi_buf);
3263 s->bi_buf = 0;
3264 s->bi_valid = 0;
3265 } else if (s->bi_valid >= 8) {
3266 put_byte(s, (Byte)s->bi_buf);
3267 s->bi_buf >>= 8;
3268 s->bi_valid -= 8;
3269 }
3270 }
3271
3272 /* ===========================================================================
3273 * Flush the bit buffer and align the output on a byte boundary
3274 */
3275 local void bi_windup(s)
3276 deflate_state *s;
3277 {
3278 if (s->bi_valid > 8) {
3279 put_short(s, s->bi_buf);
3280 } else if (s->bi_valid > 0) {
3281 put_byte(s, (Byte)s->bi_buf);
3282 }
3283 s->bi_buf = 0;
3284 s->bi_valid = 0;
3285 #ifdef DEBUG_ZLIB
3286 s->bits_sent = (s->bits_sent+7) & ~7;
3287 #endif
3288 }
3289
3290 /* ===========================================================================
3291 * Copy a stored block, storing first the length and its
3292 * one's complement if requested.
3293 */
3294 local void copy_block(s, buf, len, header)
3295 deflate_state *s;
3296 charf *buf; /* the input data */
3297 unsigned len; /* its length */
3298 int header; /* true if block header must be written */
3299 {
3300 bi_windup(s); /* align on byte boundary */
3301 s->last_eob_len = 8; /* enough lookahead for inflate */
3302
3303 if (header) {
3304 put_short(s, (ush)len);
3305 put_short(s, (ush)~len);
3306 #ifdef DEBUG_ZLIB
3307 s->bits_sent += 2*16;
3308 #endif
3309 }
3310 #ifdef DEBUG_ZLIB
3311 s->bits_sent += (ulg)len<<3;
3312 #endif
3313 while (len--) {
3314 put_byte(s, *buf++);
3315 }
3316 }
3317 /* --- trees.c */
3318
3319 /* +++ inflate.c */
3320 /* inflate.c -- zlib interface to inflate modules
3321 * Copyright (C) 1995-2002 Mark Adler
3322 * For conditions of distribution and use, see copyright notice in zlib.h
3323 */
3324
3325 /* #include "zutil.h" */
3326
3327 /* +++ infblock.h */
3328 /* infblock.h -- header to use infblock.c
3329 * Copyright (C) 1995-2002 Mark Adler
3330 * For conditions of distribution and use, see copyright notice in zlib.h
3331 */
3332
3333 /* WARNING: this file should *not* be used by applications. It is
3334 part of the implementation of the compression library and is
3335 subject to change. Applications should only use zlib.h.
3336 */
3337
3338 struct inflate_blocks_state;
3339 typedef struct inflate_blocks_state FAR inflate_blocks_statef;
3340
3341 extern inflate_blocks_statef * inflate_blocks_new OF((
3342 z_streamp z,
3343 check_func c, /* check function */
3344 uInt w)); /* window size */
3345
3346 extern int inflate_blocks OF((
3347 inflate_blocks_statef *,
3348 z_streamp ,
3349 int)); /* initial return code */
3350
3351 extern void inflate_blocks_reset OF((
3352 inflate_blocks_statef *,
3353 z_streamp ,
3354 uLongf *)); /* check value on output */
3355
3356 extern int inflate_blocks_free OF((
3357 inflate_blocks_statef *,
3358 z_streamp));
3359
3360 extern void inflate_set_dictionary OF((
3361 inflate_blocks_statef *s,
3362 const Bytef *d, /* dictionary */
3363 uInt n)); /* dictionary length */
3364
3365 extern int inflate_blocks_sync_point OF((
3366 inflate_blocks_statef *s));
3367 /* --- infblock.h */
3368
3369 #ifndef NO_DUMMY_DECL
3370 struct inflate_blocks_state {int dummy;}; /* for buggy compilers */
3371 #endif
3372
3373 /* inflate private state */
3374 typedef struct inflate_state {
3375
3376 /* mode */
3377 enum {
3378 METHOD, /* waiting for method byte */
3379 FLAG, /* waiting for flag byte */
3380 DICT4, /* four dictionary check bytes to go */
3381 DICT3, /* three dictionary check bytes to go */
3382 DICT2, /* two dictionary check bytes to go */
3383 DICT1, /* one dictionary check byte to go */
3384 DICT0, /* waiting for inflateSetDictionary */
3385 BLOCKS, /* decompressing blocks */
3386 CHECK4, /* four check bytes to go */
3387 CHECK3, /* three check bytes to go */
3388 CHECK2, /* two check bytes to go */
3389 CHECK1, /* one check byte to go */
3390 DONE, /* finished check, done */
3391 BAD} /* got an error--stay here */
3392 mode; /* current inflate mode */
3393
3394 /* mode dependent information */
3395 union {
3396 uInt method; /* if FLAGS, method byte */
3397 struct {
3398 uLong was; /* computed check value */
3399 uLong need; /* stream check value */
3400 } check; /* if CHECK, check values to compare */
3401 uInt marker; /* if BAD, inflateSync's marker bytes count */
3402 } sub; /* submode */
3403
3404 /* mode independent information */
3405 int nowrap; /* flag for no wrapper */
3406 uInt wbits; /* log2(window size) (8..15, defaults to 15) */
3407 inflate_blocks_statef
3408 *blocks; /* current inflate_blocks state */
3409
3410 }inflate_state;
3411
3412
3413 int ZEXPORT inflateReset(z)
3414 z_streamp z;
3415 {
3416 inflate_state* s;
3417 if (z == Z_NULL || z->state == Z_NULL)
3418 return Z_STREAM_ERROR;
3419
3420 s = (inflate_state*)z->state;
3421 z->total_in = z->total_out = 0;
3422 z->msg = Z_NULL;
3423 s->mode = s->nowrap ? BLOCKS : METHOD;
3424 inflate_blocks_reset(s->blocks, z, Z_NULL);
3425 Tracev((stderr, "inflate: reset\n"));
3426 return Z_OK;
3427 }
3428
3429
3430 int ZEXPORT inflateEnd(z)
3431 z_streamp z;
3432 {
3433 if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL)
3434 return Z_STREAM_ERROR;
3435 if (((inflate_state*)z->state)->blocks != Z_NULL)
3436 inflate_blocks_free(((inflate_state*)z->state)->blocks, z);
3437 ZFREE(z, z->state);
3438 z->state = Z_NULL;
3439 Tracev((stderr, "inflate: end\n"));
3440 return Z_OK;
3441 }
3442
3443
3444 int ZEXPORT inflateInit2_(z, w, version, stream_size)
3445 z_streamp z;
3446 int w;
3447 const char *version;
3448 int stream_size;
3449 {
3450 inflate_state* s;
3451 if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
3452 stream_size != sizeof(z_stream))
3453 return Z_VERSION_ERROR;
3454
3455 /* initialize state */
3456 if (z == Z_NULL)
3457 return Z_STREAM_ERROR;
3458 z->msg = Z_NULL;
3459 #ifndef NO_ZCFUNCS
3460 if (z->zalloc == Z_NULL)
3461 {
3462 z->zalloc = zcalloc;
3463 z->opaque = (voidpf)0;
3464 }
3465 if (z->zfree == Z_NULL) z->zfree = zcfree;
3466 #endif
3467 if ((z->state = (struct internal_state FAR *)
3468 ZALLOC(z,1,sizeof(struct inflate_state))) == Z_NULL)
3469 return Z_MEM_ERROR;
3470 s = (inflate_state*)z->state;
3471 s->blocks = Z_NULL;
3472
3473 /* handle undocumented nowrap option (no zlib header or check) */
3474 s->nowrap = 0;
3475 if (w < 0)
3476 {
3477 w = - w;
3478 s->nowrap = 1;
3479 }
3480
3481 /* set window size */
3482 if (w < 8 || w > 15)
3483 {
3484 inflateEnd(z);
3485 return Z_STREAM_ERROR;
3486 }
3487 s->wbits = (uInt)w;
3488
3489 /* create inflate_blocks state */
3490 if ((s->blocks =
3491 inflate_blocks_new(z, s->nowrap ? Z_NULL : adler32, (uInt)1 << w))
3492 == Z_NULL)
3493 {
3494 inflateEnd(z);
3495 return Z_MEM_ERROR;
3496 }
3497 Tracev((stderr, "inflate: allocated\n"));
3498
3499 /* reset state */
3500 inflateReset(z);
3501 return Z_OK;
3502 }
3503
3504
3505 int ZEXPORT inflateInit_(z, version, stream_size)
3506 z_streamp z;
3507 const char *version;
3508 int stream_size;
3509 {
3510 return inflateInit2_(z, DEF_WBITS, version, stream_size);
3511 }
3512
3513
3514 #define NEEDBYTE {if(z->avail_in==0)return r;r=f;}
3515 #define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++)
3516
3517 int ZEXPORT inflate(z, f)
3518 z_streamp z;
3519 int f;
3520 {
3521 int r;
3522 uInt b;
3523 inflate_state* s;
3524
3525 if (z == Z_NULL || z->state == Z_NULL || z->next_in == Z_NULL)
3526 return Z_STREAM_ERROR;
3527 f = f == Z_FINISH ? Z_BUF_ERROR : Z_OK;
3528 r = Z_BUF_ERROR;
3529 s = (inflate_state*)z->state;
3530 while (1) switch (s->mode)
3531 {
3532 case METHOD:
3533 NEEDBYTE
3534 if (((s->sub.method = NEXTBYTE) & 0xf) != Z_DEFLATED)
3535 {
3536 s->mode = BAD;
3537 z->msg = (char*)"unknown compression method";
3538 s->sub.marker = 5; /* can't try inflateSync */
3539 break;
3540 }
3541 if ((s->sub.method >> 4) + 8 > s->wbits)
3542 {
3543 s->mode = BAD;
3544 z->msg = (char*)"invalid window size";
3545 s->sub.marker = 5; /* can't try inflateSync */
3546 break;
3547 }
3548 s->mode = FLAG;
3549 case FLAG:
3550 NEEDBYTE
3551 b = NEXTBYTE;
3552 if (((s->sub.method << 8) + b) % 31)
3553 {
3554 s->mode = BAD;
3555 z->msg = (char*)"incorrect header check";
3556 s->sub.marker = 5; /* can't try inflateSync */
3557 break;
3558 }
3559 Tracev((stderr, "inflate: zlib header ok\n"));
3560 if (!(b & PRESET_DICT))
3561 {
3562 s->mode = BLOCKS;
3563 break;
3564 }
3565 s->mode = DICT4;
3566 case DICT4:
3567 NEEDBYTE
3568 s->sub.check.need = (uLong)NEXTBYTE << 24;
3569 s->mode = DICT3;
3570 case DICT3:
3571 NEEDBYTE
3572 s->sub.check.need += (uLong)NEXTBYTE << 16;
3573 s->mode = DICT2;
3574 case DICT2:
3575 NEEDBYTE
3576 s->sub.check.need += (uLong)NEXTBYTE << 8;
3577 s->mode = DICT1;
3578 case DICT1:
3579 NEEDBYTE
3580 s->sub.check.need += (uLong)NEXTBYTE;
3581 z->adler = s->sub.check.need;
3582 s->mode = DICT0;
3583 return Z_NEED_DICT;
3584 case DICT0:
3585 s->mode = BAD;
3586 z->msg = (char*)"need dictionary";
3587 s->sub.marker = 0; /* can try inflateSync */
3588 return Z_STREAM_ERROR;
3589 case BLOCKS:
3590 r = inflate_blocks(s->blocks, z, r);
3591 if (r == Z_DATA_ERROR)
3592 {
3593 s->mode = BAD;
3594 s->sub.marker = 0; /* can try inflateSync */
3595 break;
3596 }
3597 if (r == Z_OK)
3598 r = f;
3599 if (r != Z_STREAM_END)
3600 return r;
3601 r = f;
3602 inflate_blocks_reset(s->blocks, z, &s->sub.check.was);
3603 if (s->nowrap)
3604 {
3605 s->mode = DONE;
3606 break;
3607 }
3608 s->mode = CHECK4;
3609 case CHECK4:
3610 NEEDBYTE
3611 s->sub.check.need = (uLong)NEXTBYTE << 24;
3612 s->mode = CHECK3;
3613 case CHECK3:
3614 NEEDBYTE
3615 s->sub.check.need += (uLong)NEXTBYTE << 16;
3616 s->mode = CHECK2;
3617 case CHECK2:
3618 NEEDBYTE
3619 s->sub.check.need += (uLong)NEXTBYTE << 8;
3620 s->mode = CHECK1;
3621 case CHECK1:
3622 NEEDBYTE
3623 s->sub.check.need += (uLong)NEXTBYTE;
3624
3625 if (s->sub.check.was != s->sub.check.need)
3626 {
3627 s->mode = BAD;
3628 z->msg = (char*)"incorrect data check";
3629 s->sub.marker = 5; /* can't try inflateSync */
3630 break;
3631 }
3632 Tracev((stderr, "inflate: zlib check ok\n"));
3633 s->mode = DONE;
3634 case DONE:
3635 return Z_STREAM_END;
3636 case BAD:
3637 return Z_DATA_ERROR;
3638 default:
3639 return Z_STREAM_ERROR;
3640 }
3641 #ifdef NEED_DUMMY_RETURN
3642 return Z_STREAM_ERROR; /* Some dumb compilers complain without this */
3643 #endif
3644 }
3645
3646
3647 int ZEXPORT inflateSetDictionary(z, dictionary, dictLength)
3648 z_streamp z;
3649 const Bytef *dictionary;
3650 uInt dictLength;
3651 {
3652 uInt length = dictLength;
3653 inflate_state* s;
3654
3655 if (z == Z_NULL || z->state == Z_NULL || ((inflate_state*)z->state)->mode != DICT0)
3656 return Z_STREAM_ERROR;
3657 s = (inflate_state*)z->state;
3658
3659 if (adler32(1L, dictionary, dictLength) != z->adler) return Z_DATA_ERROR;
3660 z->adler = 1L;
3661
3662 if (length >= ((uInt)1<<s->wbits))
3663 {
3664 length = (1<<s->wbits)-1;
3665 dictionary += dictLength - length;
3666 }
3667 inflate_set_dictionary(s->blocks, dictionary, length);
3668 s->mode = BLOCKS;
3669 return Z_OK;
3670 }
3671
3672
3673 int ZEXPORT inflateSync(z)
3674 z_streamp z;
3675 {
3676 uInt n; /* number of bytes to look at */
3677 Bytef *p; /* pointer to bytes */
3678 uInt m; /* number of marker bytes found in a row */
3679 uLong r, w; /* temporaries to save total_in and total_out */
3680 inflate_state* s;
3681
3682 /* set up */
3683 if (z == Z_NULL || z->state == Z_NULL)
3684 return Z_STREAM_ERROR;
3685 s = (inflate_state*)z->state;
3686 if (s->mode != BAD)
3687 {
3688 s->mode = BAD;
3689 s->sub.marker = 0;
3690 }
3691 if ((n = z->avail_in) == 0)
3692 return Z_BUF_ERROR;
3693 p = z->next_in;
3694 m = s->sub.marker;
3695
3696 /* search */
3697 while (n && m < 4)
3698 {
3699 static const Byte mark[4] = {0, 0, 0xff, 0xff};
3700 if (*p == mark[m])
3701 m++;
3702 else if (*p)
3703 m = 0;
3704 else
3705 m = 4 - m;
3706 p++, n--;
3707 }
3708
3709 /* restore */
3710 z->total_in += p - z->next_in;
3711 z->next_in = p;
3712 z->avail_in = n;
3713 s->sub.marker = m;
3714
3715 /* return no joy or set up to restart on a new block */
3716 if (m != 4)
3717 return Z_DATA_ERROR;
3718 r = z->total_in; w = z->total_out;
3719 inflateReset(z);
3720 z->total_in = r; z->total_out = w;
3721 s->mode = BLOCKS;
3722 return Z_OK;
3723 }
3724
3725
3726 /* Returns true if inflate is currently at the end of a block generated
3727 * by Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
3728 * implementation to provide an additional safety check. PPP uses Z_SYNC_FLUSH
3729 * but removes the length bytes of the resulting empty stored block. When
3730 * decompressing, PPP checks that at the end of input packet, inflate is
3731 * waiting for these length bytes.
3732 */
3733 int ZEXPORT inflateSyncPoint(z)
3734 z_streamp z;
3735 {
3736 if (z == Z_NULL || z->state == Z_NULL || ((inflate_state*)z->state)->blocks == Z_NULL)
3737 return Z_STREAM_ERROR;
3738 return inflate_blocks_sync_point(((inflate_state*)z->state)->blocks);
3739 }
3740 #undef NEEDBYTE
3741 #undef NEXTBYTE
3742 /* --- inflate.c */
3743
3744 /* +++ infblock.c */
3745 /* infblock.c -- interpret and process block types to last block
3746 * Copyright (C) 1995-2002 Mark Adler
3747 * For conditions of distribution and use, see copyright notice in zlib.h
3748 */
3749
3750 /* #include "zutil.h" */
3751 /* #include "infblock.h" */
3752
3753 /* +++ inftrees.h */
3754 /* inftrees.h -- header to use inftrees.c
3755 * Copyright (C) 1995-2002 Mark Adler
3756 * For conditions of distribution and use, see copyright notice in zlib.h
3757 */
3758
3759 /* WARNING: this file should *not* be used by applications. It is
3760 part of the implementation of the compression library and is
3761 subject to change. Applications should only use zlib.h.
3762 */
3763
3764 /* Huffman code lookup table entry--this entry is four bytes for machines
3765 that have 16-bit pointers (e.g. PC's in the small or medium model). */
3766
3767 typedef struct inflate_huft_s FAR inflate_huft;
3768
3769 struct inflate_huft_s {
3770 union {
3771 struct {
3772 Byte Exop; /* number of extra bits or operation */
3773 Byte Bits; /* number of bits in this code or subcode */
3774 } what;
3775 uInt pad; /* pad structure to a power of 2 (4 bytes for */
3776 } word; /* 16-bit, 8 bytes for 32-bit int's) */
3777 uInt base; /* literal, length base, distance base,
3778 or table offset */
3779 };
3780
3781 /* Maximum size of dynamic tree. The maximum found in a long but non-
3782 exhaustive search was 1004 huft structures (850 for length/literals
3783 and 154 for distances, the latter actually the result of an
3784 exhaustive search). The actual maximum is not known, but the
3785 value below is more than safe. */
3786 #define MANY 1440
3787
3788 extern int inflate_trees_bits OF((
3789 uIntf *, /* 19 code lengths */
3790 uIntf *, /* bits tree desired/actual depth */
3791 inflate_huft * FAR *, /* bits tree result */
3792 inflate_huft *, /* space for trees */
3793 z_streamp)); /* for messages */
3794
3795 extern int inflate_trees_dynamic OF((
3796 uInt, /* number of literal/length codes */
3797 uInt, /* number of distance codes */
3798 uIntf *, /* that many (total) code lengths */
3799 uIntf *, /* literal desired/actual bit depth */
3800 uIntf *, /* distance desired/actual bit depth */
3801 inflate_huft * FAR *, /* literal/length tree result */
3802 inflate_huft * FAR *, /* distance tree result */
3803 inflate_huft *, /* space for trees */
3804 z_streamp)); /* for messages */
3805
3806 extern int inflate_trees_fixed OF((
3807 uIntf *, /* literal desired/actual bit depth */
3808 uIntf *, /* distance desired/actual bit depth */
3809 inflate_huft * FAR *, /* literal/length tree result */
3810 inflate_huft * FAR *, /* distance tree result */
3811 z_streamp)); /* for memory allocation */
3812 /* --- inftrees.h */
3813
3814 /* +++ infcodes.h */
3815 /* infcodes.h -- header to use infcodes.c
3816 * Copyright (C) 1995-2002 Mark Adler
3817 * For conditions of distribution and use, see copyright notice in zlib.h
3818 */
3819
3820 /* WARNING: this file should *not* be used by applications. It is
3821 part of the implementation of the compression library and is
3822 subject to change. Applications should only use zlib.h.
3823 */
3824
3825 struct inflate_codes_state;
3826 typedef struct inflate_codes_state FAR inflate_codes_statef;
3827
3828 extern inflate_codes_statef *inflate_codes_new OF((
3829 uInt, uInt,
3830 inflate_huft *, inflate_huft *,
3831 z_streamp ));
3832
3833 extern int inflate_codes OF((
3834 inflate_blocks_statef *,
3835 z_streamp ,
3836 int));
3837
3838 extern void inflate_codes_free OF((
3839 inflate_codes_statef *,
3840 z_streamp ));
3841
3842 /* --- infcodes.h */
3843
3844 /* +++ infutil.h */
3845 /* infutil.h -- types and macros common to blocks and codes
3846 * Copyright (C) 1995-2002 Mark Adler
3847 * For conditions of distribution and use, see copyright notice in zlib.h
3848 */
3849
3850 /* WARNING: this file should *not* be used by applications. It is
3851 part of the implementation of the compression library and is
3852 subject to change. Applications should only use zlib.h.
3853 */
3854
3855 #ifndef _INFUTIL_H
3856 #define _INFUTIL_H
3857
3858 typedef enum {
3859 TYPE, /* get type bits (3, including end bit) */
3860 LENS, /* get lengths for stored */
3861 STORED, /* processing stored block */
3862 TABLE, /* get table lengths */
3863 BTREE, /* get bit lengths tree for a dynamic block */
3864 DTREE, /* get length, distance trees for a dynamic block */
3865 CODES, /* processing fixed or dynamic block */
3866 DRY, /* output remaining window bytes */
3867 DONEB, /* finished last block, done */
3868 BADB} /* got a data error--stuck here */
3869 inflate_block_mode;
3870
3871 /* inflate blocks semi-private state */
3872 struct inflate_blocks_state {
3873
3874 /* mode */
3875 inflate_block_mode mode; /* current inflate_block mode */
3876
3877 /* mode dependent information */
3878 union {
3879 uInt left; /* if STORED, bytes left to copy */
3880 struct {
3881 uInt table; /* table lengths (14 bits) */
3882 uInt index; /* index into blens (or border) */
3883 uIntf *blens; /* bit lengths of codes */
3884 uInt bb; /* bit length tree depth */
3885 inflate_huft *tb; /* bit length decoding tree */
3886 } trees; /* if DTREE, decoding info for trees */
3887 struct {
3888 inflate_codes_statef
3889 *codes;
3890 } decode; /* if CODES, current state */
3891 } sub; /* submode */
3892 uInt last; /* true if this block is the last block */
3893
3894 /* mode independent information */
3895 uInt bitk; /* bits in bit buffer */
3896 uLong bitb; /* bit buffer */
3897 inflate_huft *hufts; /* single malloc for tree space */
3898 Bytef *window; /* sliding window */
3899 Bytef *end; /* one byte after sliding window */
3900 Bytef *read; /* window read pointer */
3901 Bytef *write; /* window write pointer */
3902 check_func checkfn; /* check function */
3903 uLong check; /* check on output */
3904
3905 };
3906
3907
3908 /* defines for inflate input/output */
3909 /* update pointers and return */
3910 #define UPDBITS {s->bitb=b;s->bitk=k;}
3911 #define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;}
3912 #define UPDOUT {s->write=q;}
3913 #define UPDATE {UPDBITS UPDIN UPDOUT}
3914 #define LEAVE {UPDATE return inflate_flush(s,z,r);}
3915 /* get bytes and bits */
3916 #define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;}
3917 #define NEEDBYTE {if(n)r=Z_OK;else LEAVE}
3918 #define NEXTBYTE (n--,*p++)
3919 #define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}}
3920 #define DUMPBITS(j) {b>>=(j);k-=(j);}
3921 /* output bytes */
3922 #define WAVAIL (uInt)(q<s->read?s->read-q-1:s->end-q)
3923 #define LOADOUT {q=s->write;m=(uInt)WAVAIL;}
3924 #define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}}
3925 #define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT}
3926 #define NEEDOUT {if(m==0){WRAP if(m==0){FLUSH WRAP if(m==0) LEAVE}}r=Z_OK;}
3927 #define OUTBYTE(a) {*q++=(Byte)(a);m--;}
3928 /* load local pointers */
3929 #define LOAD {LOADIN LOADOUT}
3930
3931 /* masks for lower bits (size given to avoid silly warnings with Visual C++) */
3932 extern uInt inflate_mask[17];
3933
3934 /* copy as much as possible from the sliding window to the output area */
3935 extern int inflate_flush OF((
3936 inflate_blocks_statef *,
3937 z_streamp ,
3938 int));
3939
3940 #ifndef NO_DUMMY_DECL
3941 struct internal_state {int dummy;}; /* for buggy compilers */
3942 #endif
3943
3944 #endif
3945 /* --- infutil.h */
3946
3947 #ifndef NO_DUMMY_DECL
3948 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
3949 #endif
3950
3951 /* simplify the use of the inflate_huft type with some defines */
3952 #define exop word.what.Exop
3953 #define bits word.what.Bits
3954
3955 /* Table for deflate from PKZIP's appnote.txt. */
3956 local const uInt border[] = { /* Order of the bit length code lengths */
3957 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
3958
3959 /*
3960 Notes beyond the 1.93a appnote.txt:
3961
3962 1. Distance pointers never point before the beginning of the output
3963 stream.
3964 2. Distance pointers can point back across blocks, up to 32k away.
3965 3. There is an implied maximum of 7 bits for the bit length table and
3966 15 bits for the actual data.
3967 4. If only one code exists, then it is encoded using one bit. (Zero
3968 would be more efficient, but perhaps a little confusing.) If two
3969 codes exist, they are coded using one bit each (0 and 1).
3970 5. There is no way of sending zero distance codes--a dummy must be
3971 sent if there are none. (History: a pre 2.0 version of PKZIP would
3972 store blocks with no distance codes, but this was discovered to be
3973 too harsh a criterion.) Valid only for 1.93a. 2.04c does allow
3974 zero distance codes, which is sent as one code of zero bits in
3975 length.
3976 6. There are up to 286 literal/length codes. Code 256 represents the
3977 end-of-block. Note however that the static length tree defines
3978 288 codes just to fill out the Huffman codes. Codes 286 and 287
3979 cannot be used though, since there is no length base or extra bits
3980 defined for them. Similarily, there are up to 30 distance codes.
3981 However, static trees define 32 codes (all 5 bits) to fill out the
3982 Huffman codes, but the last two had better not show up in the data.
3983 7. Unzip can check dynamic Huffman blocks for complete code sets.
3984 The exception is that a single code would not be complete (see #4).
3985 8. The five bits following the block type is really the number of
3986 literal codes sent minus 257.
3987 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
3988 (1+6+6). Therefore, to output three times the length, you output
3989 three codes (1+1+1), whereas to output four times the same length,
3990 you only need two codes (1+3). Hmm.
3991 10. In the tree reconstruction algorithm, Code = Code + Increment
3992 only if BitLength(i) is not zero. (Pretty obvious.)
3993 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19)
3994 12. Note: length code 284 can represent 227-258, but length code 285
3995 really is 258. The last length deserves its own, short code
3996 since it gets used a lot in very redundant files. The length
3997 258 is special since 258 - 3 (the min match length) is 255.
3998 13. The literal/length and distance code bit lengths are read as a
3999 single stream of lengths. It is possible (and advantageous) for
4000 a repeat code (16, 17, or 18) to go across the boundary between
4001 the two sets of lengths.
4002 */
4003
4004
4005 void inflate_blocks_reset(s, z, c)
4006 inflate_blocks_statef *s;
4007 z_streamp z;
4008 uLongf *c;
4009 {
4010 if (c != Z_NULL)
4011 *c = s->check;
4012 if (s->mode == BTREE || s->mode == DTREE)
4013 ZFREE(z, s->sub.trees.blens);
4014 if (s->mode == CODES)
4015 inflate_codes_free(s->sub.decode.codes, z);
4016 s->mode = TYPE;
4017 s->bitk = 0;
4018 s->bitb = 0;
4019 s->read = s->write = s->window;
4020 if (s->checkfn != Z_NULL)
4021 z->adler = s->check = (*s->checkfn)(0L, (const Bytef *)Z_NULL, 0);
4022 Tracev((stderr, "inflate: blocks reset\n"));
4023 }
4024
4025
4026 inflate_blocks_statef *inflate_blocks_new(z, c, w)
4027 z_streamp z;
4028 check_func c;
4029 uInt w;
4030 {
4031 inflate_blocks_statef *s;
4032
4033 if ((s = (inflate_blocks_statef *)ZALLOC
4034 (z,1,sizeof(struct inflate_blocks_state))) == Z_NULL)
4035 return s;
4036 if ((s->hufts =
4037 (inflate_huft *)ZALLOC(z, sizeof(inflate_huft), MANY)) == Z_NULL)
4038 {
4039 ZFREE(z, s);
4040 return Z_NULL;
4041 }
4042 if ((s->window = (Bytef *)ZALLOC(z, 1, w)) == Z_NULL)
4043 {
4044 ZFREE(z, s->hufts);
4045 ZFREE(z, s);
4046 return Z_NULL;
4047 }
4048 s->end = s->window + w;
4049 s->checkfn = c;
4050 s->mode = TYPE;
4051 Tracev((stderr, "inflate: blocks allocated\n"));
4052 inflate_blocks_reset(s, z, Z_NULL);
4053 return s;
4054 }
4055
4056
4057 int inflate_blocks(s, z, r)
4058 inflate_blocks_statef *s;
4059 z_streamp z;
4060 int r;
4061 {
4062 uInt t; /* temporary storage */
4063 uLong b; /* bit buffer */
4064 uInt k; /* bits in bit buffer */
4065 Bytef *p; /* input data pointer */
4066 uInt n; /* bytes available there */
4067 Bytef *q; /* output window write pointer */
4068 uInt m; /* bytes to end of window or read pointer */
4069
4070 /* copy input/output information to locals (UPDATE macro restores) */
4071 LOAD
4072
4073 /* process input based on current state */
4074 while (1) switch (s->mode)
4075 {
4076 case TYPE:
4077 NEEDBITS(3)
4078 t = (uInt)b & 7;
4079 s->last = t & 1;
4080 switch (t >> 1)
4081 {
4082 case 0: /* stored */
4083 Tracev((stderr, "inflate: stored block%s\n",
4084 s->last ? " (last)" : ""));
4085 DUMPBITS(3)
4086 t = k & 7; /* go to byte boundary */
4087 DUMPBITS(t)
4088 s->mode = LENS; /* get length of stored block */
4089 break;
4090 case 1: /* fixed */
4091 Tracev((stderr, "inflate: fixed codes block%s\n",
4092 s->last ? " (last)" : ""));
4093 {
4094 uInt bl, bd;
4095 inflate_huft *tl, *td;
4096
4097 inflate_trees_fixed(&bl, &bd, &tl, &td, z);
4098 s->sub.decode.codes = inflate_codes_new(bl, bd, tl, td, z);
4099 if (s->sub.decode.codes == Z_NULL)
4100 {
4101 r = Z_MEM_ERROR;
4102 LEAVE
4103 }
4104 }
4105 DUMPBITS(3)
4106 s->mode = CODES;
4107 break;
4108 case 2: /* dynamic */
4109 Tracev((stderr, "inflate: dynamic codes block%s\n",
4110 s->last ? " (last)" : ""));
4111 DUMPBITS(3)
4112 s->mode = TABLE;
4113 break;
4114 case 3: /* illegal */
4115 DUMPBITS(3)
4116 s->mode = BADB;
4117 z->msg = (char*)"invalid block type";
4118 r = Z_DATA_ERROR;
4119 LEAVE
4120 }
4121 break;
4122 case LENS:
4123 NEEDBITS(32)
4124 if ((((~b) >> 16) & 0xffff) != (b & 0xffff))
4125 {
4126 s->mode = BADB;
4127 z->msg = (char*)"invalid stored block lengths";
4128 r = Z_DATA_ERROR;
4129 LEAVE
4130 }
4131 s->sub.left = (uInt)b & 0xffff;
4132 b = k = 0; /* dump bits */
4133 Tracev((stderr, "inflate: stored length %u\n", s->sub.left));
4134 s->mode = s->sub.left ? STORED : (s->last ? DRY : TYPE);
4135 break;
4136 case STORED:
4137 if (n == 0)
4138 LEAVE
4139 NEEDOUT
4140 t = s->sub.left;
4141 if (t > n) t = n;
4142 if (t > m) t = m;
4143 zmemcpy(q, p, t);
4144 p += t; n -= t;
4145 q += t; m -= t;
4146 if ((s->sub.left -= t) != 0)
4147 break;
4148 Tracev((stderr, "inflate: stored end, %lu total out\n",
4149 z->total_out + (q >= s->read ? q - s->read :
4150 (s->end - s->read) + (q - s->window))));
4151 s->mode = s->last ? DRY : TYPE;
4152 break;
4153 case TABLE:
4154 NEEDBITS(14)
4155 s->sub.trees.table = t = (uInt)b & 0x3fff;
4156 #ifndef PKZIP_BUG_WORKAROUND
4157 if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29)
4158 {
4159 s->mode = BADB;
4160 z->msg = (char*)"too many length or distance symbols";
4161 r = Z_DATA_ERROR;
4162 LEAVE
4163 }
4164 #endif
4165 t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
4166 if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL)
4167 {
4168 r = Z_MEM_ERROR;
4169 LEAVE
4170 }
4171 DUMPBITS(14)
4172 s->sub.trees.index = 0;
4173 Tracev((stderr, "inflate: table sizes ok\n"));
4174 s->mode = BTREE;
4175 case BTREE:
4176 while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10))
4177 {
4178 NEEDBITS(3)
4179 s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7;
4180 DUMPBITS(3)
4181 }
4182 while (s->sub.trees.index < 19)
4183 s->sub.trees.blens[border[s->sub.trees.index++]] = 0;
4184 s->sub.trees.bb = 7;
4185 t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb,
4186 &s->sub.trees.tb, s->hufts, z);
4187 if (t != Z_OK)
4188 {
4189 r = t;
4190 if (r == Z_DATA_ERROR)
4191 {
4192 ZFREE(z, s->sub.trees.blens);
4193 s->mode = BADB;
4194 }
4195 LEAVE
4196 }
4197 s->sub.trees.index = 0;
4198 Tracev((stderr, "inflate: bits tree ok\n"));
4199 s->mode = DTREE;
4200 case DTREE:
4201 while (t = s->sub.trees.table,
4202 s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f))
4203 {
4204 inflate_huft *h;
4205 uInt i, j, c;
4206
4207 t = s->sub.trees.bb;
4208 NEEDBITS(t)
4209 h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]);
4210 t = h->bits;
4211 c = h->base;
4212 if (c < 16)
4213 {
4214 DUMPBITS(t)
4215 s->sub.trees.blens[s->sub.trees.index++] = c;
4216 }
4217 else /* c == 16..18 */
4218 {
4219 i = c == 18 ? 7 : c - 14;
4220 j = c == 18 ? 11 : 3;
4221 NEEDBITS(t + i)
4222 DUMPBITS(t)
4223 j += (uInt)b & inflate_mask[i];
4224 DUMPBITS(i)
4225 i = s->sub.trees.index;
4226 t = s->sub.trees.table;
4227 if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) ||
4228 (c == 16 && i < 1))
4229 {
4230 ZFREE(z, s->sub.trees.blens);
4231 s->mode = BADB;
4232 z->msg = (char*)"invalid bit length repeat";
4233 r = Z_DATA_ERROR;
4234 LEAVE
4235 }
4236 c = c == 16 ? s->sub.trees.blens[i - 1] : 0;
4237 do {
4238 s->sub.trees.blens[i++] = c;
4239 } while (--j);
4240 s->sub.trees.index = i;
4241 }
4242 }
4243 s->sub.trees.tb = Z_NULL;
4244 {
4245 uInt bl, bd;
4246 inflate_huft *tl, *td;
4247 inflate_codes_statef *c;
4248
4249 bl = 9; /* must be <= 9 for lookahead assumptions */
4250 bd = 6; /* must be <= 9 for lookahead assumptions */
4251 t = s->sub.trees.table;
4252 t = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f),
4253 s->sub.trees.blens, &bl, &bd, &tl, &td,
4254 s->hufts, z);
4255 if (t != Z_OK)
4256 {
4257 if (t == (uInt)Z_DATA_ERROR)
4258 {
4259 ZFREE(z, s->sub.trees.blens);
4260 s->mode = BADB;
4261 }
4262 r = t;
4263 LEAVE
4264 }
4265 Tracev((stderr, "inflate: trees ok\n"));
4266 if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL)
4267 {
4268 r = Z_MEM_ERROR;
4269 LEAVE
4270 }
4271 s->sub.decode.codes = c;
4272 }
4273 ZFREE(z, s->sub.trees.blens);
4274 s->mode = CODES;
4275 case CODES:
4276 UPDATE
4277 if ((r = inflate_codes(s, z, r)) != Z_STREAM_END)
4278 return inflate_flush(s, z, r);
4279 r = Z_OK;
4280 inflate_codes_free(s->sub.decode.codes, z);
4281 LOAD
4282 Tracev((stderr, "inflate: codes end, %lu total out\n",
4283 z->total_out + (q >= s->read ? q - s->read :
4284 (s->end - s->read) + (q - s->window))));
4285 if (!s->last)
4286 {
4287 s->mode = TYPE;
4288 break;
4289 }
4290 s->mode = DRY;
4291 case DRY:
4292 FLUSH
4293 if (s->read != s->write)
4294 LEAVE
4295 s->mode = DONEB;
4296 case DONEB:
4297 r = Z_STREAM_END;
4298 LEAVE
4299 case BADB:
4300 r = Z_DATA_ERROR;
4301 LEAVE
4302 default:
4303 r = Z_STREAM_ERROR;
4304 LEAVE
4305 }
4306 }
4307
4308
4309 int inflate_blocks_free(s, z)
4310 inflate_blocks_statef *s;
4311 z_streamp z;
4312 {
4313 inflate_blocks_reset(s, z, Z_NULL);
4314 ZFREE(z, s->window);
4315 ZFREE(z, s->hufts);
4316 ZFREE(z, s);
4317 Tracev((stderr, "inflate: blocks freed\n"));
4318 return Z_OK;
4319 }
4320
4321
4322 void inflate_set_dictionary(s, d, n)
4323 inflate_blocks_statef *s;
4324 const Bytef *d;
4325 uInt n;
4326 {
4327 zmemcpy(s->window, d, n);
4328 s->read = s->write = s->window + n;
4329 }
4330
4331
4332 /* Returns true if inflate is currently at the end of a block generated
4333 * by Z_SYNC_FLUSH or Z_FULL_FLUSH.
4334 * IN assertion: s != Z_NULL
4335 */
4336 int inflate_blocks_sync_point(s)
4337 inflate_blocks_statef *s;
4338 {
4339 return s->mode == LENS;
4340 }
4341 /* --- infblock.c */
4342
4343 /* +++ inftrees.c */
4344 /* inftrees.c -- generate Huffman trees for efficient decoding
4345 * Copyright (C) 1995-2002 Mark Adler
4346 * For conditions of distribution and use, see copyright notice in zlib.h
4347 */
4348
4349 /* #include "zutil.h" */
4350 /* #include "inftrees.h" */
4351
4352 #if !defined(BUILDFIXED) && !defined(STDC)
4353 # define BUILDFIXED /* non ANSI compilers may not accept inffixed.h */
4354 #endif
4355
4356 const char inflate_copyright[] =
4357 " inflate 1.1.4 Copyright 1995-2002 Mark Adler ";
4358 /*
4359 If you use the zlib library in a product, an acknowledgment is welcome
4360 in the documentation of your product. If for some reason you cannot
4361 include such an acknowledgment, I would appreciate that you keep this
4362 copyright string in the executable of your product.
4363 */
4364
4365 #ifndef NO_DUMMY_DECL
4366 struct internal_state {int dummy;}; /* for buggy compilers */
4367 #endif
4368
4369 /* simplify the use of the inflate_huft type with some defines */
4370 #define exop word.what.Exop
4371 #define bits word.what.Bits
4372
4373
4374 local int huft_build OF((
4375 uIntf *, /* code lengths in bits */
4376 uInt, /* number of codes */
4377 uInt, /* number of "simple" codes */
4378 const uIntf *, /* list of base values for non-simple codes */
4379 const uIntf *, /* list of extra bits for non-simple codes */
4380 inflate_huft * FAR*,/* result: starting table */
4381 uIntf *, /* maximum lookup bits (returns actual) */
4382 inflate_huft *, /* space for trees */
4383 uInt *, /* hufts used in space */
4384 uIntf * )); /* space for values */
4385
4386 /* Tables for deflate from PKZIP's appnote.txt. */
4387 local const uInt cplens[31] = { /* Copy lengths for literal codes 257..285 */
4388 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
4389 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
4390 /* see note #13 above about 258 */
4391 local const uInt cplext[31] = { /* Extra bits for literal codes 257..285 */
4392 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
4393 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 112, 112}; /* 112==invalid */
4394 local const uInt cpdist[30] = { /* Copy offsets for distance codes 0..29 */
4395 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
4396 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
4397 8193, 12289, 16385, 24577};
4398 local const uInt cpdext[30] = { /* Extra bits for distance codes */
4399 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
4400 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
4401 12, 12, 13, 13};
4402
4403 /*
4404 Huffman code decoding is performed using a multi-level table lookup.
4405 The fastest way to decode is to simply build a lookup table whose
4406 size is determined by the longest code. However, the time it takes
4407 to build this table can also be a factor if the data being decoded
4408 is not very long. The most common codes are necessarily the
4409 shortest codes, so those codes dominate the decoding time, and hence
4410 the speed. The idea is you can have a shorter table that decodes the
4411 shorter, more probable codes, and then point to subsidiary tables for
4412 the longer codes. The time it costs to decode the longer codes is
4413 then traded against the time it takes to make longer tables.
4414
4415 This results of this trade are in the variables lbits and dbits
4416 below. lbits is the number of bits the first level table for literal/
4417 length codes can decode in one step, and dbits is the same thing for
4418 the distance codes. Subsequent tables are also less than or equal to
4419 those sizes. These values may be adjusted either when all of the
4420 codes are shorter than that, in which case the longest code length in
4421 bits is used, or when the shortest code is *longer* than the requested
4422 table size, in which case the length of the shortest code in bits is
4423 used.
4424
4425 There are two different values for the two tables, since they code a
4426 different number of possibilities each. The literal/length table
4427 codes 286 possible values, or in a flat code, a little over eight
4428 bits. The distance table codes 30 possible values, or a little less
4429 than five bits, flat. The optimum values for speed end up being
4430 about one bit more than those, so lbits is 8+1 and dbits is 5+1.
4431 The optimum values may differ though from machine to machine, and
4432 possibly even between compilers. Your mileage may vary.
4433 */
4434
4435
4436 /* If BMAX needs to be larger than 16, then h and x[] should be uLong. */
4437 #define BMAX 15 /* maximum bit length of any code */
4438
4439 local int huft_build(b, n, s, d, e, t, m, hp, hn, v)
4440 uIntf *b; /* code lengths in bits (all assumed <= BMAX) */
4441 uInt n; /* number of codes (assumed <= 288) */
4442 uInt s; /* number of simple-valued codes (0..s-1) */
4443 const uIntf *d; /* list of base values for non-simple codes */
4444 const uIntf *e; /* list of extra bits for non-simple codes */
4445 inflate_huft * FAR *t; /* result: starting table */
4446 uIntf *m; /* maximum lookup bits, returns actual */
4447 inflate_huft *hp; /* space for trees */
4448 uInt *hn; /* hufts used in space */
4449 uIntf *v; /* working area: values in order of bit length */
4450 /* Given a list of code lengths and a maximum table size, make a set of
4451 tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR
4452 if the given code set is incomplete (the tables are still built in this
4453 case), or Z_DATA_ERROR if the input is invalid. */
4454 {
4455
4456 uInt a; /* counter for codes of length k */
4457 uInt c[BMAX+1]; /* bit length count table */
4458 uInt f; /* i repeats in table every f entries */
4459 int g; /* maximum code length */
4460 int h; /* table level */
4461 register uInt i; /* counter, current code */
4462 register uInt j; /* counter */
4463 register int k; /* number of bits in current code */
4464 int l; /* bits per table (returned in m) */
4465 uInt mask; /* (1 << w) - 1, to avoid cc -O bug on HP */
4466 register uIntf *p; /* pointer into c[], b[], or v[] */
4467 inflate_huft *q; /* points to current table */
4468 struct inflate_huft_s r; /* table entry for structure assignment */
4469 inflate_huft *u[BMAX]; /* table stack */
4470 register int w; /* bits before this table == (l * h) */
4471 uInt x[BMAX+1]; /* bit offsets, then code stack */
4472 uIntf *xp; /* pointer into x */
4473 int y; /* number of dummy codes added */
4474 uInt z; /* number of entries in current table */
4475
4476
4477 /* Generate counts for each bit length */
4478 p = c;
4479 #define C0 *p++ = 0;
4480 #define C2 C0 C0 C0 C0
4481 #define C4 C2 C2 C2 C2
4482 C4 /* clear c[]--assume BMAX+1 is 16 */
4483 p = b; i = n;
4484 do {
4485 c[*p++]++; /* assume all entries <= BMAX */
4486 } while (--i);
4487 if (c[0] == n) /* null input--all zero length codes */
4488 {
4489 *t = (inflate_huft *)Z_NULL;
4490 *m = 0;
4491 return Z_OK;
4492 }
4493
4494
4495 /* Find minimum and maximum length, bound *m by those */
4496 l = *m;
4497 for (j = 1; j <= BMAX; j++)
4498 if (c[j])
4499 break;
4500 k = j; /* minimum code length */
4501 if ((uInt)l < j)
4502 l = j;
4503 for (i = BMAX; i; i--)
4504 if (c[i])
4505 break;
4506 g = i; /* maximum code length */
4507 if ((uInt)l > i)
4508 l = i;
4509 *m = l;
4510
4511
4512 /* Adjust last length count to fill out codes, if needed */
4513 for (y = 1 << j; j < i; j++, y <<= 1)
4514 if ((y -= c[j]) < 0)
4515 return Z_DATA_ERROR;
4516 if ((y -= c[i]) < 0)
4517 return Z_DATA_ERROR;
4518 c[i] += y;
4519
4520
4521 /* Generate starting offsets into the value table for each length */
4522 x[1] = j = 0;
4523 p = c + 1; xp = x + 2;
4524 while (--i) { /* note that i == g from above */
4525 *xp++ = (j += *p++);
4526 }
4527
4528
4529 /* Make a table of values in order of bit lengths */
4530 p = b; i = 0;
4531 do {
4532 if ((j = *p++) != 0)
4533 v[x[j]++] = i;
4534 } while (++i < n);
4535 n = x[g]; /* set n to length of v */
4536
4537
4538 /* Generate the Huffman codes and for each, make the table entries */
4539 x[0] = i = 0; /* first Huffman code is zero */
4540 p = v; /* grab values in bit order */
4541 h = -1; /* no tables yet--level -1 */
4542 w = -l; /* bits decoded == (l * h) */
4543 u[0] = (inflate_huft *)Z_NULL; /* just to keep compilers happy */
4544 q = (inflate_huft *)Z_NULL; /* ditto */
4545 z = 0; /* ditto */
4546
4547 /* go through the bit lengths (k already is bits in shortest code) */
4548 for (; k <= g; k++)
4549 {
4550 a = c[k];
4551 while (a--)
4552 {
4553 /* here i is the Huffman code of length k bits for value *p */
4554 /* make tables up to required level */
4555 while (k > w + l)
4556 {
4557 h++;
4558 w += l; /* previous table always l bits */
4559
4560 /* compute minimum size table less than or equal to l bits */
4561 z = g - w;
4562 z = z > (uInt)l ? l : z; /* table size upper limit */
4563 if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */
4564 { /* too few codes for k-w bit table */
4565 f -= a + 1; /* deduct codes from patterns left */
4566 xp = c + k;
4567 if (j < z)
4568 while (++j < z) /* try smaller tables up to z bits */
4569 {
4570 if ((f <<= 1) <= *++xp)
4571 break; /* enough codes to use up j bits */
4572 f -= *xp; /* else deduct codes from patterns */
4573 }
4574 }
4575 z = 1 << j; /* table entries for j-bit table */
4576
4577 /* allocate new table */
4578 if (*hn + z > MANY) /* (note: doesn't matter for fixed) */
4579 return Z_DATA_ERROR; /* overflow of MANY */
4580 u[h] = q = hp + *hn;
4581 *hn += z;
4582
4583 /* connect to last table, if there is one */
4584 if (h)
4585 {
4586 x[h] = i; /* save pattern for backing up */
4587 r.bits = (Byte)l; /* bits to dump before this table */
4588 r.exop = (Byte)j; /* bits in this table */
4589 j = i >> (w - l);
4590 r.base = (uInt)(q - u[h-1] - j); /* offset to this table */
4591 u[h-1][j] = r; /* connect to last table */
4592 }
4593 else
4594 *t = q; /* first table is returned result */
4595 }
4596
4597 /* set up table entry in r */
4598 r.bits = (Byte)(k - w);
4599 if (p >= v + n)
4600 r.exop = 128 + 64; /* out of values--invalid code */
4601 else if (*p < s)
4602 {
4603 r.exop = (Byte)(*p < 256 ? 0 : 32 + 64); /* 256 is end-of-block */
4604 r.base = *p++; /* simple code is just the value */
4605 }
4606 else
4607 {
4608 r.exop = (Byte)(e[*p - s] + 16 + 64);/* non-simple--look up in lists */
4609 r.base = d[*p++ - s];
4610 }
4611
4612 /* fill code-like entries with r */
4613 f = 1 << (k - w);
4614 for (j = i >> w; j < z; j += f)
4615 q[j] = r;
4616
4617 /* backwards increment the k-bit code i */
4618 for (j = 1 << (k - 1); i & j; j >>= 1)
4619 i ^= j;
4620 i ^= j;
4621
4622 /* backup over finished tables */
4623 mask = (1 << w) - 1; /* needed on HP, cc -O bug */
4624 while ((i & mask) != x[h])
4625 {
4626 h--; /* don't need to update q */
4627 w -= l;
4628 mask = (1 << w) - 1;
4629 }
4630 }
4631 }
4632
4633
4634 /* Return Z_BUF_ERROR if we were given an incomplete table */
4635 return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK;
4636 }
4637
4638
4639 int inflate_trees_bits(c, bb, tb, hp, z)
4640 uIntf *c; /* 19 code lengths */
4641 uIntf *bb; /* bits tree desired/actual depth */
4642 inflate_huft * FAR *tb; /* bits tree result */
4643 inflate_huft *hp; /* space for trees */
4644 z_streamp z; /* for messages */
4645 {
4646 int r;
4647 uInt hn = 0; /* hufts used in space */
4648 uIntf *v; /* work area for huft_build */
4649
4650 if ((v = (uIntf*)ZALLOC(z, 19, sizeof(uInt))) == Z_NULL)
4651 return Z_MEM_ERROR;
4652 r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL,
4653 tb, bb, hp, &hn, v);
4654 if (r == Z_DATA_ERROR)
4655 z->msg = (char*)"oversubscribed dynamic bit lengths tree";
4656 else if (r == Z_BUF_ERROR || *bb == 0)
4657 {
4658 z->msg = (char*)"incomplete dynamic bit lengths tree";
4659 r = Z_DATA_ERROR;
4660 }
4661 ZFREE(z, v);
4662 return r;
4663 }
4664
4665
4666 int inflate_trees_dynamic(nl, nd, c, bl, bd, tl, td, hp, z)
4667 uInt nl; /* number of literal/length codes */
4668 uInt nd; /* number of distance codes */
4669 uIntf *c; /* that many (total) code lengths */
4670 uIntf *bl; /* literal desired/actual bit depth */
4671 uIntf *bd; /* distance desired/actual bit depth */
4672 inflate_huft * FAR *tl; /* literal/length tree result */
4673 inflate_huft * FAR *td; /* distance tree result */
4674 inflate_huft *hp; /* space for trees */
4675 z_streamp z; /* for messages */
4676 {
4677 int r;
4678 uInt hn = 0; /* hufts used in space */
4679 uIntf *v; /* work area for huft_build */
4680
4681 /* allocate work area */
4682 if ((v = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
4683 return Z_MEM_ERROR;
4684
4685 /* build literal/length tree */
4686 r = huft_build(c, nl, 257, cplens, cplext, tl, bl, hp, &hn, v);
4687 if (r != Z_OK || *bl == 0)
4688 {
4689 if (r == Z_DATA_ERROR)
4690 z->msg = (char*)"oversubscribed literal/length tree";
4691 else if (r != Z_MEM_ERROR)
4692 {
4693 z->msg = (char*)"incomplete literal/length tree";
4694 r = Z_DATA_ERROR;
4695 }
4696 ZFREE(z, v);
4697 return r;
4698 }
4699
4700 /* build distance tree */
4701 r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, hp, &hn, v);
4702 if (r != Z_OK || (*bd == 0 && nl > 257))
4703 {
4704 if (r == Z_DATA_ERROR)
4705 z->msg = (char*)"oversubscribed distance tree";
4706 else if (r == Z_BUF_ERROR) {
4707 #ifdef PKZIP_BUG_WORKAROUND
4708 r = Z_OK;
4709 }
4710 #else
4711 z->msg = (char*)"incomplete distance tree";
4712 r = Z_DATA_ERROR;
4713 }
4714 else if (r != Z_MEM_ERROR)
4715 {
4716 z->msg = (char*)"empty distance tree with lengths";
4717 r = Z_DATA_ERROR;
4718 }
4719 ZFREE(z, v);
4720 return r;
4721 #endif
4722 }
4723
4724 /* done */
4725 ZFREE(z, v);
4726 return Z_OK;
4727 }
4728
4729
4730 /* build fixed tables only once--keep them here */
4731 #ifdef BUILDFIXED
4732 local int fixed_built = 0;
4733 #define FIXEDH 544 /* number of hufts used by fixed tables */
4734 local inflate_huft fixed_mem[FIXEDH];
4735 local uInt fixed_bl;
4736 local uInt fixed_bd;
4737 local inflate_huft *fixed_tl;
4738 local inflate_huft *fixed_td;
4739 #else
4740 /* +++ inffixed.h */
4741 /* inffixed.h -- table for decoding fixed codes
4742 * Generated automatically by the maketree.c program
4743 */
4744
4745 /* WARNING: this file should *not* be used by applications. It is
4746 part of the implementation of the compression library and is
4747 subject to change. Applications should only use zlib.h.
4748 */
4749
4750 local uInt fixed_bl = 9;
4751 local uInt fixed_bd = 5;
4752 local inflate_huft fixed_tl[] = {
4753 {{{96,7}},256}, {{{0,8}},80}, {{{0,8}},16}, {{{84,8}},115},
4754 {{{82,7}},31}, {{{0,8}},112}, {{{0,8}},48}, {{{0,9}},192},
4755 {{{80,7}},10}, {{{0,8}},96}, {{{0,8}},32}, {{{0,9}},160},
4756 {{{0,8}},0}, {{{0,8}},128}, {{{0,8}},64}, {{{0,9}},224},
4757 {{{80,7}},6}, {{{0,8}},88}, {{{0,8}},24}, {{{0,9}},144},
4758 {{{83,7}},59}, {{{0,8}},120}, {{{0,8}},56}, {{{0,9}},208},
4759 {{{81,7}},17}, {{{0,8}},104}, {{{0,8}},40}, {{{0,9}},176},
4760 {{{0,8}},8}, {{{0,8}},136}, {{{0,8}},72}, {{{0,9}},240},
4761 {{{80,7}},4}, {{{0,8}},84}, {{{0,8}},20}, {{{85,8}},227},
4762 {{{83,7}},43}, {{{0,8}},116}, {{{0,8}},52}, {{{0,9}},200},
4763 {{{81,7}},13}, {{{0,8}},100}, {{{0,8}},36}, {{{0,9}},168},
4764 {{{0,8}},4}, {{{0,8}},132}, {{{0,8}},68}, {{{0,9}},232},
4765 {{{80,7}},8}, {{{0,8}},92}, {{{0,8}},28}, {{{0,9}},152},
4766 {{{84,7}},83}, {{{0,8}},124}, {{{0,8}},60}, {{{0,9}},216},
4767 {{{82,7}},23}, {{{0,8}},108}, {{{0,8}},44}, {{{0,9}},184},
4768 {{{0,8}},12}, {{{0,8}},140}, {{{0,8}},76}, {{{0,9}},248},
4769 {{{80,7}},3}, {{{0,8}},82}, {{{0,8}},18}, {{{85,8}},163},
4770 {{{83,7}},35}, {{{0,8}},114}, {{{0,8}},50}, {{{0,9}},196},
4771 {{{81,7}},11}, {{{0,8}},98}, {{{0,8}},34}, {{{0,9}},164},
4772 {{{0,8}},2}, {{{0,8}},130}, {{{0,8}},66}, {{{0,9}},228},
4773 {{{80,7}},7}, {{{0,8}},90}, {{{0,8}},26}, {{{0,9}},148},
4774 {{{84,7}},67}, {{{0,8}},122}, {{{0,8}},58}, {{{0,9}},212},
4775 {{{82,7}},19}, {{{0,8}},106}, {{{0,8}},42}, {{{0,9}},180},
4776 {{{0,8}},10}, {{{0,8}},138}, {{{0,8}},74}, {{{0,9}},244},
4777 {{{80,7}},5}, {{{0,8}},86}, {{{0,8}},22}, {{{192,8}},0},
4778 {{{83,7}},51}, {{{0,8}},118}, {{{0,8}},54}, {{{0,9}},204},
4779 {{{81,7}},15}, {{{0,8}},102}, {{{0,8}},38}, {{{0,9}},172},
4780 {{{0,8}},6}, {{{0,8}},134}, {{{0,8}},70}, {{{0,9}},236},
4781 {{{80,7}},9}, {{{0,8}},94}, {{{0,8}},30}, {{{0,9}},156},
4782 {{{84,7}},99}, {{{0,8}},126}, {{{0,8}},62}, {{{0,9}},220},
4783 {{{82,7}},27}, {{{0,8}},110}, {{{0,8}},46}, {{{0,9}},188},
4784 {{{0,8}},14}, {{{0,8}},142}, {{{0,8}},78}, {{{0,9}},252},
4785 {{{96,7}},256}, {{{0,8}},81}, {{{0,8}},17}, {{{85,8}},131},
4786 {{{82,7}},31}, {{{0,8}},113}, {{{0,8}},49}, {{{0,9}},194},
4787 {{{80,7}},10}, {{{0,8}},97}, {{{0,8}},33}, {{{0,9}},162},
4788 {{{0,8}},1}, {{{0,8}},129}, {{{0,8}},65}, {{{0,9}},226},
4789 {{{80,7}},6}, {{{0,8}},89}, {{{0,8}},25}, {{{0,9}},146},
4790 {{{83,7}},59}, {{{0,8}},121}, {{{0,8}},57}, {{{0,9}},210},
4791 {{{81,7}},17}, {{{0,8}},105}, {{{0,8}},41}, {{{0,9}},178},
4792 {{{0,8}},9}, {{{0,8}},137}, {{{0,8}},73}, {{{0,9}},242},
4793 {{{80,7}},4}, {{{0,8}},85}, {{{0,8}},21}, {{{80,8}},258},
4794 {{{83,7}},43}, {{{0,8}},117}, {{{0,8}},53}, {{{0,9}},202},
4795 {{{81,7}},13}, {{{0,8}},101}, {{{0,8}},37}, {{{0,9}},170},
4796 {{{0,8}},5}, {{{0,8}},133}, {{{0,8}},69}, {{{0,9}},234},
4797 {{{80,7}},8}, {{{0,8}},93}, {{{0,8}},29}, {{{0,9}},154},
4798 {{{84,7}},83}, {{{0,8}},125}, {{{0,8}},61}, {{{0,9}},218},
4799 {{{82,7}},23}, {{{0,8}},109}, {{{0,8}},45}, {{{0,9}},186},
4800 {{{0,8}},13}, {{{0,8}},141}, {{{0,8}},77}, {{{0,9}},250},
4801 {{{80,7}},3}, {{{0,8}},83}, {{{0,8}},19}, {{{85,8}},195},
4802 {{{83,7}},35}, {{{0,8}},115}, {{{0,8}},51}, {{{0,9}},198},
4803 {{{81,7}},11}, {{{0,8}},99}, {{{0,8}},35}, {{{0,9}},166},
4804 {{{0,8}},3}, {{{0,8}},131}, {{{0,8}},67}, {{{0,9}},230},
4805 {{{80,7}},7}, {{{0,8}},91}, {{{0,8}},27}, {{{0,9}},150},
4806 {{{84,7}},67}, {{{0,8}},123}, {{{0,8}},59}, {{{0,9}},214},
4807 {{{82,7}},19}, {{{0,8}},107}, {{{0,8}},43}, {{{0,9}},182},
4808 {{{0,8}},11}, {{{0,8}},139}, {{{0,8}},75}, {{{0,9}},246},
4809 {{{80,7}},5}, {{{0,8}},87}, {{{0,8}},23}, {{{192,8}},0},
4810 {{{83,7}},51}, {{{0,8}},119}, {{{0,8}},55}, {{{0,9}},206},
4811 {{{81,7}},15}, {{{0,8}},103}, {{{0,8}},39}, {{{0,9}},174},
4812 {{{0,8}},7}, {{{0,8}},135}, {{{0,8}},71}, {{{0,9}},238},
4813 {{{80,7}},9}, {{{0,8}},95}, {{{0,8}},31}, {{{0,9}},158},
4814 {{{84,7}},99}, {{{0,8}},127}, {{{0,8}},63}, {{{0,9}},222},
4815 {{{82,7}},27}, {{{0,8}},111}, {{{0,8}},47}, {{{0,9}},190},
4816 {{{0,8}},15}, {{{0,8}},143}, {{{0,8}},79}, {{{0,9}},254},
4817 {{{96,7}},256}, {{{0,8}},80}, {{{0,8}},16}, {{{84,8}},115},
4818 {{{82,7}},31}, {{{0,8}},112}, {{{0,8}},48}, {{{0,9}},193},
4819 {{{80,7}},10}, {{{0,8}},96}, {{{0,8}},32}, {{{0,9}},161},
4820 {{{0,8}},0}, {{{0,8}},128}, {{{0,8}},64}, {{{0,9}},225},
4821 {{{80,7}},6}, {{{0,8}},88}, {{{0,8}},24}, {{{0,9}},145},
4822 {{{83,7}},59}, {{{0,8}},120}, {{{0,8}},56}, {{{0,9}},209},
4823 {{{81,7}},17}, {{{0,8}},104}, {{{0,8}},40}, {{{0,9}},177},
4824 {{{0,8}},8}, {{{0,8}},136}, {{{0,8}},72}, {{{0,9}},241},
4825 {{{80,7}},4}, {{{0,8}},84}, {{{0,8}},20}, {{{85,8}},227},
4826 {{{83,7}},43}, {{{0,8}},116}, {{{0,8}},52}, {{{0,9}},201},
4827 {{{81,7}},13}, {{{0,8}},100}, {{{0,8}},36}, {{{0,9}},169},
4828 {{{0,8}},4}, {{{0,8}},132}, {{{0,8}},68}, {{{0,9}},233},
4829 {{{80,7}},8}, {{{0,8}},92}, {{{0,8}},28}, {{{0,9}},153},
4830 {{{84,7}},83}, {{{0,8}},124}, {{{0,8}},60}, {{{0,9}},217},
4831 {{{82,7}},23}, {{{0,8}},108}, {{{0,8}},44}, {{{0,9}},185},
4832 {{{0,8}},12}, {{{0,8}},140}, {{{0,8}},76}, {{{0,9}},249},
4833 {{{80,7}},3}, {{{0,8}},82}, {{{0,8}},18}, {{{85,8}},163},
4834 {{{83,7}},35}, {{{0,8}},114}, {{{0,8}},50}, {{{0,9}},197},
4835 {{{81,7}},11}, {{{0,8}},98}, {{{0,8}},34}, {{{0,9}},165},
4836 {{{0,8}},2}, {{{0,8}},130}, {{{0,8}},66}, {{{0,9}},229},
4837 {{{80,7}},7}, {{{0,8}},90}, {{{0,8}},26}, {{{0,9}},149},
4838 {{{84,7}},67}, {{{0,8}},122}, {{{0,8}},58}, {{{0,9}},213},
4839 {{{82,7}},19}, {{{0,8}},106}, {{{0,8}},42}, {{{0,9}},181},
4840 {{{0,8}},10}, {{{0,8}},138}, {{{0,8}},74}, {{{0,9}},245},
4841 {{{80,7}},5}, {{{0,8}},86}, {{{0,8}},22}, {{{192,8}},0},
4842 {{{83,7}},51}, {{{0,8}},118}, {{{0,8}},54}, {{{0,9}},205},
4843 {{{81,7}},15}, {{{0,8}},102}, {{{0,8}},38}, {{{0,9}},173},
4844 {{{0,8}},6}, {{{0,8}},134}, {{{0,8}},70}, {{{0,9}},237},
4845 {{{80,7}},9}, {{{0,8}},94}, {{{0,8}},30}, {{{0,9}},157},
4846 {{{84,7}},99}, {{{0,8}},126}, {{{0,8}},62}, {{{0,9}},221},
4847 {{{82,7}},27}, {{{0,8}},110}, {{{0,8}},46}, {{{0,9}},189},
4848 {{{0,8}},14}, {{{0,8}},142}, {{{0,8}},78}, {{{0,9}},253},
4849 {{{96,7}},256}, {{{0,8}},81}, {{{0,8}},17}, {{{85,8}},131},
4850 {{{82,7}},31}, {{{0,8}},113}, {{{0,8}},49}, {{{0,9}},195},
4851 {{{80,7}},10}, {{{0,8}},97}, {{{0,8}},33}, {{{0,9}},163},
4852 {{{0,8}},1}, {{{0,8}},129}, {{{0,8}},65}, {{{0,9}},227},
4853 {{{80,7}},6}, {{{0,8}},89}, {{{0,8}},25}, {{{0,9}},147},
4854 {{{83,7}},59}, {{{0,8}},121}, {{{0,8}},57}, {{{0,9}},211},
4855 {{{81,7}},17}, {{{0,8}},105}, {{{0,8}},41}, {{{0,9}},179},
4856 {{{0,8}},9}, {{{0,8}},137}, {{{0,8}},73}, {{{0,9}},243},
4857 {{{80,7}},4}, {{{0,8}},85}, {{{0,8}},21}, {{{80,8}},258},
4858 {{{83,7}},43}, {{{0,8}},117}, {{{0,8}},53}, {{{0,9}},203},
4859 {{{81,7}},13}, {{{0,8}},101}, {{{0,8}},37}, {{{0,9}},171},
4860 {{{0,8}},5}, {{{0,8}},133}, {{{0,8}},69}, {{{0,9}},235},
4861 {{{80,7}},8}, {{{0,8}},93}, {{{0,8}},29}, {{{0,9}},155},
4862 {{{84,7}},83}, {{{0,8}},125}, {{{0,8}},61}, {{{0,9}},219},
4863 {{{82,7}},23}, {{{0,8}},109}, {{{0,8}},45}, {{{0,9}},187},
4864 {{{0,8}},13}, {{{0,8}},141}, {{{0,8}},77}, {{{0,9}},251},
4865 {{{80,7}},3}, {{{0,8}},83}, {{{0,8}},19}, {{{85,8}},195},
4866 {{{83,7}},35}, {{{0,8}},115}, {{{0,8}},51}, {{{0,9}},199},
4867 {{{81,7}},11}, {{{0,8}},99}, {{{0,8}},35}, {{{0,9}},167},
4868 {{{0,8}},3}, {{{0,8}},131}, {{{0,8}},67}, {{{0,9}},231},
4869 {{{80,7}},7}, {{{0,8}},91}, {{{0,8}},27}, {{{0,9}},151},
4870 {{{84,7}},67}, {{{0,8}},123}, {{{0,8}},59}, {{{0,9}},215},
4871 {{{82,7}},19}, {{{0,8}},107}, {{{0,8}},43}, {{{0,9}},183},
4872 {{{0,8}},11}, {{{0,8}},139}, {{{0,8}},75}, {{{0,9}},247},
4873 {{{80,7}},5}, {{{0,8}},87}, {{{0,8}},23}, {{{192,8}},0},
4874 {{{83,7}},51}, {{{0,8}},119}, {{{0,8}},55}, {{{0,9}},207},
4875 {{{81,7}},15}, {{{0,8}},103}, {{{0,8}},39}, {{{0,9}},175},
4876 {{{0,8}},7}, {{{0,8}},135}, {{{0,8}},71}, {{{0,9}},239},
4877 {{{80,7}},9}, {{{0,8}},95}, {{{0,8}},31}, {{{0,9}},159},
4878 {{{84,7}},99}, {{{0,8}},127}, {{{0,8}},63}, {{{0,9}},223},
4879 {{{82,7}},27}, {{{0,8}},111}, {{{0,8}},47}, {{{0,9}},191},
4880 {{{0,8}},15}, {{{0,8}},143}, {{{0,8}},79}, {{{0,9}},255}
4881 };
4882 local inflate_huft fixed_td[] = {
4883 {{{80,5}},1}, {{{87,5}},257}, {{{83,5}},17}, {{{91,5}},4097},
4884 {{{81,5}},5}, {{{89,5}},1025}, {{{85,5}},65}, {{{93,5}},16385},
4885 {{{80,5}},3}, {{{88,5}},513}, {{{84,5}},33}, {{{92,5}},8193},
4886 {{{82,5}},9}, {{{90,5}},2049}, {{{86,5}},129}, {{{192,5}},24577},
4887 {{{80,5}},2}, {{{87,5}},385}, {{{83,5}},25}, {{{91,5}},6145},
4888 {{{81,5}},7}, {{{89,5}},1537}, {{{85,5}},97}, {{{93,5}},24577},
4889 {{{80,5}},4}, {{{88,5}},769}, {{{84,5}},49}, {{{92,5}},12289},
4890 {{{82,5}},13}, {{{90,5}},3073}, {{{86,5}},193}, {{{192,5}},24577}
4891 };
4892 /* --- inffixed.h */
4893 #endif
4894
4895
4896 int inflate_trees_fixed(bl, bd, tl, td, z)
4897 uIntf *bl; /* literal desired/actual bit depth */
4898 uIntf *bd; /* distance desired/actual bit depth */
4899 inflate_huft * FAR *tl; /* literal/length tree result */
4900 inflate_huft * FAR *td; /* distance tree result */
4901 z_streamp z; /* for memory allocation */
4902 {
4903 #ifdef BUILDFIXED
4904 /* build fixed tables if not already */
4905 if (!fixed_built)
4906 {
4907 int k; /* temporary variable */
4908 uInt f = 0; /* number of hufts used in fixed_mem */
4909 uIntf *c; /* length list for huft_build */
4910 uIntf *v; /* work area for huft_build */
4911
4912 /* allocate memory */
4913 if ((c = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
4914 return Z_MEM_ERROR;
4915 if ((v = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
4916 {
4917 ZFREE(z, c);
4918 return Z_MEM_ERROR;
4919 }
4920
4921 /* literal table */
4922 for (k = 0; k < 144; k++)
4923 c[k] = 8;
4924 for (; k < 256; k++)
4925 c[k] = 9;
4926 for (; k < 280; k++)
4927 c[k] = 7;
4928 for (; k < 288; k++)
4929 c[k] = 8;
4930 fixed_bl = 9;
4931 huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl,
4932 fixed_mem, &f, v);
4933
4934 /* distance table */
4935 for (k = 0; k < 30; k++)
4936 c[k] = 5;
4937 fixed_bd = 5;
4938 huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd,
4939 fixed_mem, &f, v);
4940
4941 /* done */
4942 ZFREE(z, v);
4943 ZFREE(z, c);
4944 fixed_built = 1;
4945 }
4946 #endif
4947 *bl = fixed_bl;
4948 *bd = fixed_bd;
4949 *tl = fixed_tl;
4950 *td = fixed_td;
4951 return Z_OK;
4952 }
4953 /* --- inftrees.c */
4954
4955 /* +++ infcodes.c */
4956 /* infcodes.c -- process literals and length/distance pairs
4957 * Copyright (C) 1995-2002 Mark Adler
4958 * For conditions of distribution and use, see copyright notice in zlib.h
4959 */
4960
4961 /* #include "zutil.h" */
4962 /* #include "inftrees.h" */
4963 /* #include "infblock.h" */
4964 /* #include "infcodes.h" */
4965 /* #include "infutil.h" */
4966
4967 /* +++ inffast.h */
4968 /* inffast.h -- header to use inffast.c
4969 * Copyright (C) 1995-2002 Mark Adler
4970 * For conditions of distribution and use, see copyright notice in zlib.h
4971 */
4972
4973 /* WARNING: this file should *not* be used by applications. It is
4974 part of the implementation of the compression library and is
4975 subject to change. Applications should only use zlib.h.
4976 */
4977
4978 extern int inflate_fast OF((
4979 uInt,
4980 uInt,
4981 inflate_huft *,
4982 inflate_huft *,
4983 inflate_blocks_statef *,
4984 z_streamp ));
4985 /* --- inffast.h */
4986
4987 /* simplify the use of the inflate_huft type with some defines */
4988 #define exop word.what.Exop
4989 #define bits word.what.Bits
4990
4991 typedef enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
4992 START, /* x: set up for LEN */
4993 LEN, /* i: get length/literal/eob next */
4994 LENEXT, /* i: getting length extra (have base) */
4995 DIST, /* i: get distance next */
4996 DISTEXT, /* i: getting distance extra */
4997 COPY, /* o: copying bytes in window, waiting for space */
4998 LIT, /* o: got literal, waiting for output space */
4999 WASH, /* o: got eob, possibly still output waiting */
5000 END, /* x: got eob and all data flushed */
5001 BADCODE} /* x: got error */
5002 inflate_codes_mode;
5003
5004 /* inflate codes private state */
5005 struct inflate_codes_state {
5006
5007 /* mode */
5008 inflate_codes_mode mode; /* current inflate_codes mode */
5009
5010 /* mode dependent information */
5011 uInt len;
5012 union {
5013 struct {
5014 inflate_huft *tree; /* pointer into tree */
5015 uInt need; /* bits needed */
5016 } code; /* if LEN or DIST, where in tree */
5017 uInt lit; /* if LIT, literal */
5018 struct {
5019 uInt get; /* bits to get for extra */
5020 uInt dist; /* distance back to copy from */
5021 } copy; /* if EXT or COPY, where and how much */
5022 } sub; /* submode */
5023
5024 /* mode independent information */
5025 Byte lbits; /* ltree bits decoded per branch */
5026 Byte dbits; /* dtree bits decoder per branch */
5027 inflate_huft *ltree; /* literal/length/eob tree */
5028 inflate_huft *dtree; /* distance tree */
5029
5030 };
5031
5032
5033 inflate_codes_statef *inflate_codes_new(bl, bd, tl, td, z)
5034 uInt bl, bd;
5035 inflate_huft *tl;
5036 inflate_huft *td; /* need separate declaration for Borland C++ */
5037 z_streamp z;
5038 {
5039 inflate_codes_statef *c;
5040
5041 if ((c = (inflate_codes_statef *)
5042 ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL)
5043 {
5044 c->mode = START;
5045 c->lbits = (Byte)bl;
5046 c->dbits = (Byte)bd;
5047 c->ltree = tl;
5048 c->dtree = td;
5049 Tracev((stderr, "inflate: codes new\n"));
5050 }
5051 return c;
5052 }
5053
5054
5055 int inflate_codes(s, z, r)
5056 inflate_blocks_statef *s;
5057 z_streamp z;
5058 int r;
5059 {
5060 uInt j; /* temporary storage */
5061 inflate_huft *t; /* temporary pointer */
5062 uInt e; /* extra bits or operation */
5063 uLong b; /* bit buffer */
5064 uInt k; /* bits in bit buffer */
5065 Bytef *p; /* input data pointer */
5066 uInt n; /* bytes available there */
5067 Bytef *q; /* output window write pointer */
5068 uInt m; /* bytes to end of window or read pointer */
5069 Bytef *f; /* pointer to copy strings from */
5070 inflate_codes_statef *c = s->sub.decode.codes; /* codes state */
5071
5072 /* copy input/output information to locals (UPDATE macro restores) */
5073 LOAD
5074
5075 /* process input and output based on current state */
5076 while (1) switch (c->mode)
5077 { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
5078 case START: /* x: set up for LEN */
5079 #ifndef SLOW
5080 if (m >= 258 && n >= 10)
5081 {
5082 UPDATE
5083 r = inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z);
5084 LOAD
5085 if (r != Z_OK)
5086 {
5087 c->mode = r == Z_STREAM_END ? WASH : BADCODE;
5088 break;
5089 }
5090 }
5091 #endif /* !SLOW */
5092 c->sub.code.need = c->lbits;
5093 c->sub.code.tree = c->ltree;
5094 c->mode = LEN;
5095 case LEN: /* i: get length/literal/eob next */
5096 j = c->sub.code.need;
5097 NEEDBITS(j)
5098 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
5099 DUMPBITS(t->bits)
5100 e = (uInt)(t->exop);
5101 if (e == 0) /* literal */
5102 {
5103 c->sub.lit = t->base;
5104 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5105 "inflate: literal '%c'\n" :
5106 "inflate: literal 0x%02x\n", t->base));
5107 c->mode = LIT;
5108 break;
5109 }
5110 if (e & 16) /* length */
5111 {
5112 c->sub.copy.get = e & 15;
5113 c->len = t->base;
5114 c->mode = LENEXT;
5115 break;
5116 }
5117 if ((e & 64) == 0) /* next table */
5118 {
5119 c->sub.code.need = e;
5120 c->sub.code.tree = t + t->base;
5121 break;
5122 }
5123 if (e & 32) /* end of block */
5124 {
5125 Tracevv((stderr, "inflate: end of block\n"));
5126 c->mode = WASH;
5127 break;
5128 }
5129 c->mode = BADCODE; /* invalid code */
5130 z->msg = (char*)"invalid literal/length code";
5131 r = Z_DATA_ERROR;
5132 LEAVE
5133 case LENEXT: /* i: getting length extra (have base) */
5134 j = c->sub.copy.get;
5135 NEEDBITS(j)
5136 c->len += (uInt)b & inflate_mask[j];
5137 DUMPBITS(j)
5138 c->sub.code.need = c->dbits;
5139 c->sub.code.tree = c->dtree;
5140 Tracevv((stderr, "inflate: length %u\n", c->len));
5141 c->mode = DIST;
5142 case DIST: /* i: get distance next */
5143 j = c->sub.code.need;
5144 NEEDBITS(j)
5145 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
5146 DUMPBITS(t->bits)
5147 e = (uInt)(t->exop);
5148 if (e & 16) /* distance */
5149 {
5150 c->sub.copy.get = e & 15;
5151 c->sub.copy.dist = t->base;
5152 c->mode = DISTEXT;
5153 break;
5154 }
5155 if ((e & 64) == 0) /* next table */
5156 {
5157 c->sub.code.need = e;
5158 c->sub.code.tree = t + t->base;
5159 break;
5160 }
5161 c->mode = BADCODE; /* invalid code */
5162 z->msg = (char*)"invalid distance code";
5163 r = Z_DATA_ERROR;
5164 LEAVE
5165 case DISTEXT: /* i: getting distance extra */
5166 j = c->sub.copy.get;
5167 NEEDBITS(j)
5168 c->sub.copy.dist += (uInt)b & inflate_mask[j];
5169 DUMPBITS(j)
5170 Tracevv((stderr, "inflate: distance %u\n", c->sub.copy.dist));
5171 c->mode = COPY;
5172 case COPY: /* o: copying bytes in window, waiting for space */
5173 f = q - c->sub.copy.dist;
5174 while (f < s->window) /* modulo window size-"while" instead */
5175 f += s->end - s->window; /* of "if" handles invalid distances */
5176 while (c->len)
5177 {
5178 NEEDOUT
5179 OUTBYTE(*f++)
5180 if (f == s->end)
5181 f = s->window;
5182 c->len--;
5183 }
5184 c->mode = START;
5185 break;
5186 case LIT: /* o: got literal, waiting for output space */
5187 NEEDOUT
5188 OUTBYTE(c->sub.lit)
5189 c->mode = START;
5190 break;
5191 case WASH: /* o: got eob, possibly more output */
5192 if (k > 7) /* return unused byte, if any */
5193 {
5194 Assert(k < 16, "inflate_codes grabbed too many bytes")
5195 k -= 8;
5196 n++;
5197 p--; /* can always return one */
5198 }
5199 FLUSH
5200 if (s->read != s->write)
5201 LEAVE
5202 c->mode = END;
5203 case END:
5204 r = Z_STREAM_END;
5205 LEAVE
5206 case BADCODE: /* x: got error */
5207 r = Z_DATA_ERROR;
5208 LEAVE
5209 default:
5210 r = Z_STREAM_ERROR;
5211 LEAVE
5212 }
5213 #ifdef NEED_DUMMY_RETURN
5214 return Z_STREAM_ERROR; /* Some dumb compilers complain without this */
5215 #endif
5216 }
5217
5218
5219 void inflate_codes_free(c, z)
5220 inflate_codes_statef *c;
5221 z_streamp z;
5222 {
5223 ZFREE(z, c);
5224 Tracev((stderr, "inflate: codes free\n"));
5225 }
5226 /* --- infcodes.c */
5227
5228 /* +++ infutil.c */
5229 /* inflate_util.c -- data and routines common to blocks and codes
5230 * Copyright (C) 1995-2002 Mark Adler
5231 * For conditions of distribution and use, see copyright notice in zlib.h
5232 */
5233
5234 /* #include "zutil.h" */
5235 /* #include "infblock.h" */
5236 /* #include "inftrees.h" */
5237 /* #include "infcodes.h" */
5238 /* #include "infutil.h" */
5239
5240 #ifndef NO_DUMMY_DECL
5241 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
5242 #endif
5243
5244 /* And'ing with mask[n] masks the lower n bits */
5245 uInt inflate_mask[17] = {
5246 0x0000,
5247 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
5248 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
5249 };
5250
5251
5252 /* copy as much as possible from the sliding window to the output area */
5253 int inflate_flush(s, z, r)
5254 inflate_blocks_statef *s;
5255 z_streamp z;
5256 int r;
5257 {
5258 uInt n;
5259 Bytef *p;
5260 Bytef *q;
5261
5262 /* local copies of source and destination pointers */
5263 p = z->next_out;
5264 q = s->read;
5265
5266 /* compute number of bytes to copy as far as end of window */
5267 n = (uInt)((q <= s->write ? s->write : s->end) - q);
5268 if (n > z->avail_out) n = z->avail_out;
5269 if (n && r == Z_BUF_ERROR) r = Z_OK;
5270
5271 /* update counters */
5272 z->avail_out -= n;
5273 z->total_out += n;
5274
5275 /* update check information */
5276 if (s->checkfn != Z_NULL)
5277 z->adler = s->check = (*s->checkfn)(s->check, q, n);
5278
5279 /* copy as far as end of window */
5280 zmemcpy(p, q, n);
5281 p += n;
5282 q += n;
5283
5284 /* see if more to copy at beginning of window */
5285 if (q == s->end)
5286 {
5287 /* wrap pointers */
5288 q = s->window;
5289 if (s->write == s->end)
5290 s->write = s->window;
5291
5292 /* compute bytes to copy */
5293 n = (uInt)(s->write - q);
5294 if (n > z->avail_out) n = z->avail_out;
5295 if (n && r == Z_BUF_ERROR) r = Z_OK;
5296
5297 /* update counters */
5298 z->avail_out -= n;
5299 z->total_out += n;
5300
5301 /* update check information */
5302 if (s->checkfn != Z_NULL)
5303 z->adler = s->check = (*s->checkfn)(s->check, q, n);
5304
5305 /* copy */
5306 zmemcpy(p, q, n);
5307 p += n;
5308 q += n;
5309 }
5310
5311 /* update pointers */
5312 z->next_out = p;
5313 s->read = q;
5314
5315 /* done */
5316 return r;
5317 }
5318 /* --- infutil.c */
5319
5320 /* +++ inffast.c */
5321 /* inffast.c -- process literals and length/distance pairs fast
5322 * Copyright (C) 1995-2002 Mark Adler
5323 * For conditions of distribution and use, see copyright notice in zlib.h
5324 */
5325
5326 /* #include "zutil.h" */
5327 /* #include "inftrees.h" */
5328 /* #include "infblock.h" */
5329 /* #include "infcodes.h" */
5330 /* #include "infutil.h" */
5331 /* #include "inffast.h" */
5332
5333 #ifndef NO_DUMMY_DECL
5334 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
5335 #endif
5336
5337 /* simplify the use of the inflate_huft type with some defines */
5338 #define exop word.what.Exop
5339 #define bits word.what.Bits
5340
5341 /* macros for bit input with no checking and for returning unused bytes */
5342 #define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}}
5343 #define UNGRAB {c=z->avail_in-n;c=(k>>3)<c?k>>3:c;n+=c;p-=c;k-=c<<3;}
5344
5345 /* Called with number of bytes left to write in window at least 258
5346 (the maximum string length) and number of input bytes available
5347 at least ten. The ten bytes are six bytes for the longest length/
5348 distance pair plus four bytes for overloading the bit buffer. */
5349
5350 int inflate_fast(bl, bd, tl, td, s, z)
5351 uInt bl, bd;
5352 inflate_huft *tl;
5353 inflate_huft *td; /* need separate declaration for Borland C++ */
5354 inflate_blocks_statef *s;
5355 z_streamp z;
5356 {
5357 inflate_huft *t; /* temporary pointer */
5358 uInt e; /* extra bits or operation */
5359 uLong b; /* bit buffer */
5360 uInt k; /* bits in bit buffer */
5361 Bytef *p; /* input data pointer */
5362 uInt n; /* bytes available there */
5363 Bytef *q; /* output window write pointer */
5364 uInt m; /* bytes to end of window or read pointer */
5365 uInt ml; /* mask for literal/length tree */
5366 uInt md; /* mask for distance tree */
5367 uInt c; /* bytes to copy */
5368 uInt d; /* distance back to copy from */
5369 Bytef *r; /* copy source pointer */
5370
5371 /* load input, output, bit values */
5372 LOAD
5373
5374 /* initialize masks */
5375 ml = inflate_mask[bl];
5376 md = inflate_mask[bd];
5377
5378 /* do until not enough input or output space for fast loop */
5379 do { /* assume called with m >= 258 && n >= 10 */
5380 /* get literal/length code */
5381 GRABBITS(20) /* max bits for literal/length code */
5382 if ((e = (t = tl + ((uInt)b & ml))->exop) == 0)
5383 {
5384 DUMPBITS(t->bits)
5385 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5386 "inflate: * literal '%c'\n" :
5387 "inflate: * literal 0x%02x\n", t->base));
5388 *q++ = (Byte)t->base;
5389 m--;
5390 continue;
5391 }
5392 do {
5393 DUMPBITS(t->bits)
5394 if (e & 16)
5395 {
5396 /* get extra bits for length */
5397 e &= 15;
5398 c = t->base + ((uInt)b & inflate_mask[e]);
5399 DUMPBITS(e)
5400 Tracevv((stderr, "inflate: * length %u\n", c));
5401
5402 /* decode distance base of block to copy */
5403 GRABBITS(15); /* max bits for distance code */
5404 e = (t = td + ((uInt)b & md))->exop;
5405 do {
5406 DUMPBITS(t->bits)
5407 if (e & 16)
5408 {
5409 /* get extra bits to add to distance base */
5410 e &= 15;
5411 GRABBITS(e) /* get extra bits (up to 13) */
5412 d = t->base + ((uInt)b & inflate_mask[e]);
5413 DUMPBITS(e)
5414 Tracevv((stderr, "inflate: * distance %u\n", d));
5415
5416 /* do the copy */
5417 m -= c;
5418 r = q - d;
5419 if (r < s->window) /* wrap if needed */
5420 {
5421 do {
5422 r += s->end - s->window; /* force pointer in window */
5423 } while (r < s->window); /* covers invalid distances */
5424 e = s->end - r;
5425 if (c > e)
5426 {
5427 c -= e; /* wrapped copy */
5428 do {
5429 *q++ = *r++;
5430 } while (--e);
5431 r = s->window;
5432 do {
5433 *q++ = *r++;
5434 } while (--c);
5435 }
5436 else /* normal copy */
5437 {
5438 *q++ = *r++; c--;
5439 *q++ = *r++; c--;
5440 do {
5441 *q++ = *r++;
5442 } while (--c);
5443 }
5444 }
5445 else /* normal copy */
5446 {
5447 *q++ = *r++; c--;
5448 *q++ = *r++; c--;
5449 do {
5450 *q++ = *r++;
5451 } while (--c);
5452 }
5453 break;
5454 }
5455 else if ((e & 64) == 0)
5456 {
5457 t += t->base;
5458 e = (t += ((uInt)b & inflate_mask[e]))->exop;
5459 }
5460 else
5461 {
5462 z->msg = (char*)"invalid distance code";
5463 UNGRAB
5464 UPDATE
5465 return Z_DATA_ERROR;
5466 }
5467 } while (1);
5468 break;
5469 }
5470 if ((e & 64) == 0)
5471 {
5472 t += t->base;
5473 if ((e = (t += ((uInt)b & inflate_mask[e]))->exop) == 0)
5474 {
5475 DUMPBITS(t->bits)
5476 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5477 "inflate: * literal '%c'\n" :
5478 "inflate: * literal 0x%02x\n", t->base));
5479 *q++ = (Byte)t->base;
5480 m--;
5481 break;
5482 }
5483 }
5484 else if (e & 32)
5485 {
5486 Tracevv((stderr, "inflate: * end of block\n"));
5487 UNGRAB
5488 UPDATE
5489 return Z_STREAM_END;
5490 }
5491 else
5492 {
5493 z->msg = (char*)"invalid literal/length code";
5494 UNGRAB
5495 UPDATE
5496 return Z_DATA_ERROR;
5497 }
5498 } while (1);
5499 } while (m >= 258 && n >= 10);
5500
5501 /* not enough input or output--restore pointers and return */
5502 UNGRAB
5503 UPDATE
5504 return Z_OK;
5505 }
5506 /* --- inffast.c */
5507
5508 /* +++ zutil.c */
5509 /* zutil.c -- target dependent utility functions for the compression library
5510 * Copyright (C) 1995-2002 Jean-loup Gailly.
5511 * For conditions of distribution and use, see copyright notice in zlib.h
5512 */
5513
5514 /* @(#) $Id: zlib.c,v 1.8 2002/03/29 03:16:07 lindak Exp $ */
5515
5516 /* #include "zutil.h" */
5517
5518 #ifndef NO_DUMMY_DECL
5519 struct internal_state {int dummy;}; /* for buggy compilers */
5520 #endif
5521
5522 #ifndef STDC
5523 extern void exit OF((int));
5524 #endif
5525
5526 const char *z_errmsg[10] = {
5527 "need dictionary", /* Z_NEED_DICT 2 */
5528 "stream end", /* Z_STREAM_END 1 */
5529 "", /* Z_OK 0 */
5530 "file error", /* Z_ERRNO (-1) */
5531 "stream error", /* Z_STREAM_ERROR (-2) */
5532 "data error", /* Z_DATA_ERROR (-3) */
5533 "insufficient memory", /* Z_MEM_ERROR (-4) */
5534 "buffer error", /* Z_BUF_ERROR (-5) */
5535 "incompatible version",/* Z_VERSION_ERROR (-6) */
5536 ""};
5537
5538
5539 const char * ZEXPORT zlibVersion()
5540 {
5541 return ZLIB_VERSION;
5542 }
5543
5544 #ifdef DEBUG_ZLIB
5545
5546 # ifndef verbose
5547 # define verbose 0
5548 # endif
5549 int z_verbose = verbose;
5550
5551 void z_error (m)
5552 char *m;
5553 {
5554 fprintf(stderr, "%s\n", m);
5555 exit(1);
5556 }
5557 #endif
5558
5559 /* exported to allow conversion of error code to string for compress() and
5560 * uncompress()
5561 */
5562 const char * ZEXPORT zError(err)
5563 int err;
5564 {
5565 return ERR_MSG(err);
5566 }
5567
5568
5569 #ifndef HAVE_MEMCPY
5570
5571 void zmemcpy(dest, source, len)
5572 Bytef* dest;
5573 const Bytef* source;
5574 uInt len;
5575 {
5576 if (len == 0) return;
5577 do {
5578 *dest++ = *source++; /* ??? to be unrolled */
5579 } while (--len != 0);
5580 }
5581
5582 int zmemcmp(s1, s2, len)
5583 const Bytef* s1;
5584 const Bytef* s2;
5585 uInt len;
5586 {
5587 uInt j;
5588
5589 for (j = 0; j < len; j++) {
5590 if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1;
5591 }
5592 return 0;
5593 }
5594
5595 void zmemzero(dest, len)
5596 Bytef* dest;
5597 uInt len;
5598 {
5599 if (len == 0) return;
5600 do {
5601 *dest++ = 0; /* ??? to be unrolled */
5602 } while (--len != 0);
5603 }
5604 #endif
5605
5606 #ifdef __TURBOC__
5607 #if (defined( __BORLANDC__) || !defined(SMALL_MEDIUM)) && !defined(__32BIT__)
5608 /* Small and medium model in Turbo C are for now limited to near allocation
5609 * with reduced MAX_WBITS and MAX_MEM_LEVEL
5610 */
5611 # define MY_ZCALLOC
5612
5613 /* Turbo C malloc() does not allow dynamic allocation of 64K bytes
5614 * and farmalloc(64K) returns a pointer with an offset of 8, so we
5615 * must fix the pointer. Warning: the pointer must be put back to its
5616 * original form in order to free it, use zcfree().
5617 */
5618
5619 #define MAX_PTR 10
5620 /* 10*64K = 640K */
5621
5622 local int next_ptr = 0;
5623
5624 typedef struct ptr_table_s {
5625 voidpf org_ptr;
5626 voidpf new_ptr;
5627 } ptr_table;
5628
5629 local ptr_table table[MAX_PTR];
5630 /* This table is used to remember the original form of pointers
5631 * to large buffers (64K). Such pointers are normalized with a zero offset.
5632 * Since MSDOS is not a preemptive multitasking OS, this table is not
5633 * protected from concurrent access. This hack doesn't work anyway on
5634 * a protected system like OS/2. Use Microsoft C instead.
5635 */
5636
5637 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
5638 {
5639 voidpf buf = opaque; /* just to make some compilers happy */
5640 ulg bsize = (ulg)items*size;
5641
5642 /* If we allocate less than 65520 bytes, we assume that farmalloc
5643 * will return a usable pointer which doesn't have to be normalized.
5644 */
5645 if (bsize < 65520L) {
5646 buf = farmalloc(bsize);
5647 if (*(ush*)&buf != 0) return buf;
5648 } else {
5649 buf = farmalloc(bsize + 16L);
5650 }
5651 if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
5652 table[next_ptr].org_ptr = buf;
5653
5654 /* Normalize the pointer to seg:0 */
5655 *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
5656 *(ush*)&buf = 0;
5657 table[next_ptr++].new_ptr = buf;
5658 return buf;
5659 }
5660
5661 void zcfree (voidpf opaque, voidpf ptr)
5662 {
5663 int n;
5664 if (*(ush*)&ptr != 0) { /* object < 64K */
5665 farfree(ptr);
5666 return;
5667 }
5668 /* Find the original pointer */
5669 for (n = 0; n < next_ptr; n++) {
5670 if (ptr != table[n].new_ptr) continue;
5671
5672 farfree(table[n].org_ptr);
5673 while (++n < next_ptr) {
5674 table[n-1] = table[n];
5675 }
5676 next_ptr--;
5677 return;
5678 }
5679 ptr = opaque; /* just to make some compilers happy */
5680 Assert(0, "zcfree: ptr not found");
5681 }
5682 #endif
5683 #endif /* __TURBOC__ */
5684
5685
5686 #if defined(M_I86) && !defined(__32BIT__)
5687 /* Microsoft C in 16-bit mode */
5688
5689 # define MY_ZCALLOC
5690
5691 #if (!defined(_MSC_VER) || (_MSC_VER <= 600))
5692 # define _halloc halloc
5693 # define _hfree hfree
5694 #endif
5695
5696 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
5697 {
5698 if (opaque) opaque = 0; /* to make compiler happy */
5699 return _halloc((long)items, size);
5700 }
5701
5702 void zcfree (voidpf opaque, voidpf ptr)
5703 {
5704 if (opaque) opaque = 0; /* to make compiler happy */
5705 _hfree(ptr);
5706 }
5707
5708 #endif /* MSC */
5709
5710
5711 #ifndef MY_ZCALLOC /* Any system without a special alloc function */
5712
5713 #ifndef STDC
5714 extern voidp calloc OF((uInt items, uInt size));
5715 extern void free OF((voidpf ptr));
5716 #endif
5717
5718 voidpf zcalloc (opaque, items, size)
5719 voidpf opaque;
5720 unsigned items;
5721 unsigned size;
5722 {
5723 if (opaque) items += size - size; /* make compiler happy */
5724 return (voidpf)calloc(items, size);
5725 }
5726
5727 void zcfree (opaque, ptr)
5728 voidpf opaque;
5729 voidpf ptr;
5730 {
5731 _FREE(ptr);
5732 if (opaque) return; /* make compiler happy */
5733 }
5734
5735 #endif /* MY_ZCALLOC */
5736 /* --- zutil.c */
5737
5738 /* +++ adler32.c */
5739 /* adler32.c -- compute the Adler-32 checksum of a data stream
5740 * Copyright (C) 1995-2002 Mark Adler
5741 * For conditions of distribution and use, see copyright notice in zlib.h
5742 */
5743
5744 /* @(#) $Id: zlib.c,v 1.8 2002/03/29 03:16:07 lindak Exp $ */
5745
5746 /* #include "zlib.h" */
5747
5748 #define BASE 65521L /* largest prime smaller than 65536 */
5749 #define NMAX 5552
5750 /* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
5751
5752 #define DO1(buf,i) {s1 += buf[i]; s2 += s1;}
5753 #define DO2(buf,i) DO1(buf,i); DO1(buf,i+1);
5754 #define DO4(buf,i) DO2(buf,i); DO2(buf,i+2);
5755 #define DO8(buf,i) DO4(buf,i); DO4(buf,i+4);
5756 #define DO16(buf) DO8(buf,0); DO8(buf,8);
5757
5758 /* ========================================================================= */
5759 uLong ZEXPORT adler32(adler, buf, len)
5760 uLong adler;
5761 const Bytef *buf;
5762 uInt len;
5763 {
5764 unsigned long s1 = adler & 0xffff;
5765 unsigned long s2 = (adler >> 16) & 0xffff;
5766 int k;
5767
5768 if (buf == Z_NULL) return 1L;
5769
5770 while (len > 0) {
5771 k = len < NMAX ? len : NMAX;
5772 len -= k;
5773 while (k >= 16) {
5774 DO16(buf);
5775 buf += 16;
5776 k -= 16;
5777 }
5778 if (k != 0) do {
5779 s1 += *buf++;
5780 s2 += s1;
5781 } while (--k);
5782 s1 %= BASE;
5783 s2 %= BASE;
5784 }
5785 return (s2 << 16) | s1;
5786 }
5787 /* --- adler32.c */