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1 /*
2 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
6 * The contents of this file constitute Original Code as defined in and
7 * are subject to the Apple Public Source License Version 1.1 (the
8 * "License"). You may not use this file except in compliance with the
9 * License. Please obtain a copy of the License at
10 * http://www.apple.com/publicsource and read it before using this file.
11 *
12 * This Original Code and all software distributed under the License are
13 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
14 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
15 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
17 * License for the specific language governing rights and limitations
18 * under the License.
19 *
20 * @APPLE_LICENSE_HEADER_END@
21 */
22 /*
23 * This file is derived from various .h and .c files from the zlib-1.0.4
24 * distribution by Jean-loup Gailly and Mark Adler, with some additions
25 * by Paul Mackerras to aid in implementing Deflate compression and
26 * decompression for PPP packets. See zlib.h for conditions of
27 * distribution and use.
28 *
29 * Changes that have been made include:
30 * - added Z_PACKET_FLUSH (see zlib.h for details)
31 * - added inflateIncomp and deflateOutputPending
32 * - allow strm->next_out to be NULL, meaning discard the output
33 *
34 * $FreeBSD: src/sys/net/zlib.c,v 1.10 1999/12/29 04:38:38 peter Exp $
35 */
36
37 #define NO_DUMMY_DECL
38 #define NO_ZCFUNCS
39 #define MY_ZCALLOC
40
41 /* +++ zutil.h */
42 /* zutil.h -- internal interface and configuration of the compression library
43 * Copyright (C) 1995-2002 Jean-loup Gailly.
44 * For conditions of distribution and use, see copyright notice in zlib.h
45 */
46
47 /* WARNING: this file should *not* be used by applications. It is
48 part of the implementation of the compression library and is
49 subject to change. Applications should only use zlib.h.
50 */
51
52 /* @(#) $Id: zlib.c,v 1.10 2004/07/29 19:17:20 lindak Exp $ */
53
54 #ifndef _Z_UTIL_H
55 #define _Z_UTIL_H
56
57 #ifdef KERNEL
58 #include <net/zlib.h>
59 #else
60 #include "zlib.h"
61 #endif
62
63 #ifdef KERNEL
64 /* Assume this is a *BSD or SVR4 kernel */
65 #include <sys/types.h>
66 #include <sys/time.h>
67 #include <sys/systm.h>
68 # define HAVE_MEMCPY
69 # define memcpy(d, s, n) bcopy((s), (d), (n))
70 # define memset(d, v, n) bzero((d), (n))
71 # define memcmp bcmp
72
73 #else
74 #if defined(__KERNEL__)
75 /* Assume this is a Linux kernel */
76 #include <linux/string.h>
77 #define HAVE_MEMCPY
78
79 #else /* not kernel */
80 #ifdef STDC
81 # include <stddef.h>
82 # include <string.h>
83 # include <stdlib.h>
84 #endif
85 #ifdef NO_ERRNO_H
86 extern int errno;
87 #else
88 # include <errno.h>
89 #endif
90 #endif /* __KERNEL__ */
91 #endif /* KERNEL */
92
93 #ifndef local
94 # define local static
95 #endif
96 /* compile with -Dlocal if your debugger can't find static symbols */
97
98 typedef unsigned char uch;
99 typedef uch FAR uchf;
100 typedef unsigned short ush;
101 typedef ush FAR ushf;
102 typedef unsigned long ulg;
103
104 extern const char *z_errmsg[10]; /* indexed by 2-zlib_error */
105 /* (size given to avoid silly warnings with Visual C++) */
106
107 #define ERR_MSG(err) z_errmsg[Z_NEED_DICT-(err)]
108
109 #define ERR_RETURN(strm,err) \
110 return (strm->msg = (char*)ERR_MSG(err), (err))
111 /* To be used only when the state is known to be valid */
112
113 /* common constants */
114
115 #ifndef DEF_WBITS
116 # define DEF_WBITS MAX_WBITS
117 #endif
118 /* default windowBits for decompression. MAX_WBITS is for compression only */
119
120 #if MAX_MEM_LEVEL >= 8
121 # define DEF_MEM_LEVEL 8
122 #else
123 # define DEF_MEM_LEVEL MAX_MEM_LEVEL
124 #endif
125 /* default memLevel */
126
127 #define STORED_BLOCK 0
128 #define STATIC_TREES 1
129 #define DYN_TREES 2
130 /* The three kinds of block type */
131
132 #define MIN_MATCH 3
133 #define MAX_MATCH 258
134 /* The minimum and maximum match lengths */
135
136 #define PRESET_DICT 0x20 /* preset dictionary flag in zlib header */
137
138 /* target dependencies */
139
140 #ifdef MSDOS
141 # define OS_CODE 0x00
142 # if defined(__TURBOC__) || defined(__BORLANDC__)
143 # if(__STDC__ == 1) && (defined(__LARGE__) || defined(__COMPACT__))
144 /* Allow compilation with ANSI keywords only enabled */
145 void _Cdecl farfree( void *block );
146 void *_Cdecl farmalloc( unsigned long nbytes );
147 # else
148 # include <alloc.h>
149 # endif
150 # else /* MSC or DJGPP */
151 # include <malloc.h>
152 # endif
153 #endif
154
155 #ifdef OS2
156 # define OS_CODE 0x06
157 #endif
158
159 #ifdef WIN32 /* Window 95 & Windows NT */
160 # define OS_CODE 0x0b
161 #endif
162
163 #if defined(VAXC) || defined(VMS)
164 # define OS_CODE 0x02
165 # define F_OPEN(name, mode) \
166 fopen((name), (mode), "mbc=60", "ctx=stm", "rfm=fix", "mrs=512")
167 #endif
168
169 #ifdef AMIGA
170 # define OS_CODE 0x01
171 #endif
172
173 #if defined(ATARI) || defined(atarist)
174 # define OS_CODE 0x05
175 #endif
176
177 #if defined(MACOS) || defined(TARGET_OS_MAC)
178 # define OS_CODE 0x07
179 # if defined(__MWERKS__) && __dest_os != __be_os && __dest_os != __win32_os
180 # include <unix.h> /* for fdopen */
181 # else
182 # ifndef fdopen
183 # define fdopen(fd,mode) NULL /* No fdopen() */
184 # endif
185 # endif
186 #endif
187
188 #ifdef __50SERIES /* Prime/PRIMOS */
189 # define OS_CODE 0x0F
190 #endif
191
192 #ifdef TOPS20
193 # define OS_CODE 0x0a
194 #endif
195
196 #if defined(_BEOS_) || defined(RISCOS)
197 # define fdopen(fd,mode) NULL /* No fdopen() */
198 #endif
199
200 #if (defined(_MSC_VER) && (_MSC_VER > 600))
201 # define fdopen(fd,type) _fdopen(fd,type)
202 #endif
203
204
205 /* Common defaults */
206
207 #ifndef OS_CODE
208 # define OS_CODE 0x03 /* assume Unix */
209 #endif
210
211 #ifndef F_OPEN
212 # define F_OPEN(name, mode) fopen((name), (mode))
213 #endif
214
215 /* functions */
216
217 #ifdef HAVE_STRERROR
218 extern char *strerror OF((int));
219 # define zstrerror(errnum) strerror(errnum)
220 #else
221 # define zstrerror(errnum) ""
222 #endif
223
224 #if defined(pyr)
225 # define NO_MEMCPY
226 #endif
227 #if defined(SMALL_MEDIUM) && !defined(_MSC_VER) && !defined(__SC__)
228 /* Use our own functions for small and medium model with MSC <= 5.0.
229 * You may have to use the same strategy for Borland C (untested).
230 * The __SC__ check is for Symantec.
231 */
232 # define NO_MEMCPY
233 #endif
234 #if defined(STDC) && !defined(HAVE_MEMCPY) && !defined(NO_MEMCPY)
235 # define HAVE_MEMCPY
236 #endif
237 #ifdef HAVE_MEMCPY
238 # ifdef SMALL_MEDIUM /* MSDOS small or medium model */
239 # define zmemcpy _fmemcpy
240 # define zmemcmp _fmemcmp
241 # define zmemzero(dest, len) _fmemset(dest, 0, len)
242 # else
243 # define zmemcpy memcpy
244 # define zmemcmp memcmp
245 # define zmemzero(dest, len) memset(dest, 0, len)
246 # endif
247 #else
248 extern void zmemcpy OF((Bytef* dest, const Bytef* source, uInt len));
249 extern int zmemcmp OF((const Bytef* s1, const Bytef* s2, uInt len));
250 extern void zmemzero OF((Bytef* dest, uInt len));
251 #endif
252
253 /* Diagnostic functions */
254 #ifdef DEBUG_ZLIB
255 # include <stdio.h>
256 extern int z_verbose;
257 extern void z_error OF((char *m));
258 # define Assert(cond,msg) {if(!(cond)) z_error(msg);}
259 # define Trace(x) {if (z_verbose>=0) fprintf x ;}
260 # define Tracev(x) {if (z_verbose>0) fprintf x ;}
261 # define Tracevv(x) {if (z_verbose>1) fprintf x ;}
262 # define Tracec(c,x) {if (z_verbose>0 && (c)) fprintf x ;}
263 # define Tracecv(c,x) {if (z_verbose>1 && (c)) fprintf x ;}
264 #else
265 # define Assert(cond,msg)
266 # define Trace(x)
267 # define Tracev(x)
268 # define Tracevv(x)
269 # define Tracec(c,x)
270 # define Tracecv(c,x)
271 #endif
272
273
274 typedef uLong (ZEXPORT *check_func) OF((uLong check, const Bytef *buf,
275 uInt len));
276 voidpf zcalloc OF((voidpf opaque, unsigned items, unsigned size));
277 void zcfree OF((voidpf opaque, voidpf ptr));
278
279 #define ZALLOC(strm, items, size) \
280 (*((strm)->zalloc))((strm)->opaque, (items), (size))
281 #define ZFREE(strm, addr) (*((strm)->zfree))((strm)->opaque, (voidpf)(addr))
282 #define TRY_FREE(s, p) {if (p) ZFREE(s, p);}
283
284 #endif /* _Z_UTIL_H */
285 /* --- zutil.h */
286
287 /* +++ deflate.h */
288 /* deflate.h -- internal compression state
289 * Copyright (C) 1995-2002 Jean-loup Gailly
290 * For conditions of distribution and use, see copyright notice in zlib.h
291 */
292
293 /* WARNING: this file should *not* be used by applications. It is
294 part of the implementation of the compression library and is
295 subject to change. Applications should only use zlib.h.
296 */
297
298 /* @(#) $Id: zlib.c,v 1.10 2004/07/29 19:17:20 lindak Exp $ */
299
300 #ifndef _DEFLATE_H
301 #define _DEFLATE_H
302
303 /* #include "zutil.h" */
304
305 /* ===========================================================================
306 * Internal compression state.
307 */
308
309 #define LENGTH_CODES 29
310 /* number of length codes, not counting the special END_BLOCK code */
311
312 #define LITERALS 256
313 /* number of literal bytes 0..255 */
314
315 #define L_CODES (LITERALS+1+LENGTH_CODES)
316 /* number of Literal or Length codes, including the END_BLOCK code */
317
318 #define D_CODES 30
319 /* number of distance codes */
320
321 #define BL_CODES 19
322 /* number of codes used to transfer the bit lengths */
323
324 #define HEAP_SIZE (2*L_CODES+1)
325 /* maximum heap size */
326
327 #define MAX_BITS 15
328 /* All codes must not exceed MAX_BITS bits */
329
330 #define INIT_STATE 42
331 #define BUSY_STATE 113
332 #define FINISH_STATE 666
333 /* Stream status */
334
335
336 /* Data structure describing a single value and its code string. */
337 typedef struct ct_data_s {
338 union {
339 ush freq; /* frequency count */
340 ush code; /* bit string */
341 } fc;
342 union {
343 ush dad; /* father node in Huffman tree */
344 ush len; /* length of bit string */
345 } dl;
346 } FAR ct_data;
347
348 #define Freq fc.freq
349 #define Code fc.code
350 #define Dad dl.dad
351 #define Len dl.len
352
353 typedef struct static_tree_desc_s static_tree_desc;
354
355 typedef struct tree_desc_s {
356 ct_data *dyn_tree; /* the dynamic tree */
357 int max_code; /* largest code with non zero frequency */
358 static_tree_desc *stat_desc; /* the corresponding static tree */
359 } FAR tree_desc;
360
361 typedef ush Pos;
362 typedef Pos FAR Posf;
363 typedef unsigned IPos;
364
365 /* A Pos is an index in the character window. We use short instead of int to
366 * save space in the various tables. IPos is used only for parameter passing.
367 */
368
369 typedef struct deflate_state {
370 z_streamp strm; /* pointer back to this zlib stream */
371 int status; /* as the name implies */
372 Bytef *pending_buf; /* output still pending */
373 ulg pending_buf_size; /* size of pending_buf */
374 Bytef *pending_out; /* next pending byte to output to the stream */
375 int pending; /* nb of bytes in the pending buffer */
376 int noheader; /* suppress zlib header and adler32 */
377 Byte data_type; /* UNKNOWN, BINARY or ASCII */
378 Byte method; /* STORED (for zip only) or DEFLATED */
379 int last_flush; /* value of flush param for previous deflate call */
380
381 /* used by deflate.c: */
382
383 uInt w_size; /* LZ77 window size (32K by default) */
384 uInt w_bits; /* log2(w_size) (8..16) */
385 uInt w_mask; /* w_size - 1 */
386
387 Bytef *window;
388 /* Sliding window. Input bytes are read into the second half of the window,
389 * and move to the first half later to keep a dictionary of at least wSize
390 * bytes. With this organization, matches are limited to a distance of
391 * wSize-MAX_MATCH bytes, but this ensures that IO is always
392 * performed with a length multiple of the block size. Also, it limits
393 * the window size to 64K, which is quite useful on MSDOS.
394 * To do: use the user input buffer as sliding window.
395 */
396
397 ulg window_size;
398 /* Actual size of window: 2*wSize, except when the user input buffer
399 * is directly used as sliding window.
400 */
401
402 Posf *prev;
403 /* Link to older string with same hash index. To limit the size of this
404 * array to 64K, this link is maintained only for the last 32K strings.
405 * An index in this array is thus a window index modulo 32K.
406 */
407
408 Posf *head; /* Heads of the hash chains or NIL. */
409
410 uInt ins_h; /* hash index of string to be inserted */
411 uInt hash_size; /* number of elements in hash table */
412 uInt hash_bits; /* log2(hash_size) */
413 uInt hash_mask; /* hash_size-1 */
414
415 uInt hash_shift;
416 /* Number of bits by which ins_h must be shifted at each input
417 * step. It must be such that after MIN_MATCH steps, the oldest
418 * byte no longer takes part in the hash key, that is:
419 * hash_shift * MIN_MATCH >= hash_bits
420 */
421
422 long block_start;
423 /* Window position at the beginning of the current output block. Gets
424 * negative when the window is moved backwards.
425 */
426
427 uInt match_length; /* length of best match */
428 IPos prev_match; /* previous match */
429 int match_available; /* set if previous match exists */
430 uInt strstart; /* start of string to insert */
431 uInt match_start; /* start of matching string */
432 uInt lookahead; /* number of valid bytes ahead in window */
433
434 uInt prev_length;
435 /* Length of the best match at previous step. Matches not greater than this
436 * are discarded. This is used in the lazy match evaluation.
437 */
438
439 uInt max_chain_length;
440 /* To speed up deflation, hash chains are never searched beyond this
441 * length. A higher limit improves compression ratio but degrades the
442 * speed.
443 */
444
445 uInt max_lazy_match;
446 /* Attempt to find a better match only when the current match is strictly
447 * smaller than this value. This mechanism is used only for compression
448 * levels >= 4.
449 */
450 # define max_insert_length max_lazy_match
451 /* Insert new strings in the hash table only if the match length is not
452 * greater than this length. This saves time but degrades compression.
453 * max_insert_length is used only for compression levels <= 3.
454 */
455
456 int level; /* compression level (1..9) */
457 int strategy; /* favor or force Huffman coding*/
458
459 uInt good_match;
460 /* Use a faster search when the previous match is longer than this */
461
462 int nice_match; /* Stop searching when current match exceeds this */
463
464 /* used by trees.c: */
465 /* Didn't use ct_data typedef below to supress compiler warning */
466 struct ct_data_s dyn_ltree[HEAP_SIZE]; /* literal and length tree */
467 struct ct_data_s dyn_dtree[2*D_CODES+1]; /* distance tree */
468 struct ct_data_s bl_tree[2*BL_CODES+1]; /* Huffman tree for bit lengths */
469
470 struct tree_desc_s l_desc; /* desc. for literal tree */
471 struct tree_desc_s d_desc; /* desc. for distance tree */
472 struct tree_desc_s bl_desc; /* desc. for bit length tree */
473
474 ush bl_count[MAX_BITS+1];
475 /* number of codes at each bit length for an optimal tree */
476
477 int heap[2*L_CODES+1]; /* heap used to build the Huffman trees */
478 int heap_len; /* number of elements in the heap */
479 int heap_max; /* element of largest frequency */
480 /* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used.
481 * The same heap array is used to build all trees.
482 */
483
484 uch depth[2*L_CODES+1];
485 /* Depth of each subtree used as tie breaker for trees of equal frequency
486 */
487
488 uchf *l_buf; /* buffer for literals or lengths */
489
490 uInt lit_bufsize;
491 /* Size of match buffer for literals/lengths. There are 4 reasons for
492 * limiting lit_bufsize to 64K:
493 * - frequencies can be kept in 16 bit counters
494 * - if compression is not successful for the first block, all input
495 * data is still in the window so we can still emit a stored block even
496 * when input comes from standard input. (This can also be done for
497 * all blocks if lit_bufsize is not greater than 32K.)
498 * - if compression is not successful for a file smaller than 64K, we can
499 * even emit a stored file instead of a stored block (saving 5 bytes).
500 * This is applicable only for zip (not gzip or zlib).
501 * - creating new Huffman trees less frequently may not provide fast
502 * adaptation to changes in the input data statistics. (Take for
503 * example a binary file with poorly compressible code followed by
504 * a highly compressible string table.) Smaller buffer sizes give
505 * fast adaptation but have of course the overhead of transmitting
506 * trees more frequently.
507 * - I can't count above 4
508 */
509
510 uInt last_lit; /* running index in l_buf */
511
512 ushf *d_buf;
513 /* Buffer for distances. To simplify the code, d_buf and l_buf have
514 * the same number of elements. To use different lengths, an extra flag
515 * array would be necessary.
516 */
517
518 ulg opt_len; /* bit length of current block with optimal trees */
519 ulg static_len; /* bit length of current block with static trees */
520 uInt matches; /* number of string matches in current block */
521 int last_eob_len; /* bit length of EOB code for last block */
522
523 #ifdef DEBUG_ZLIB
524 ulg compressed_len; /* total bit length of compressed file mod 2^32 */
525 ulg bits_sent; /* bit length of compressed data sent mod 2^32 */
526 #endif
527
528 ush bi_buf;
529 /* Output buffer. bits are inserted starting at the bottom (least
530 * significant bits).
531 */
532 int bi_valid;
533 /* Number of valid bits in bi_buf. All bits above the last valid bit
534 * are always zero.
535 */
536
537 } FAR deflate_state;
538
539 /* Output a byte on the stream.
540 * IN assertion: there is enough room in pending_buf.
541 */
542 #define put_byte(s, c) {s->pending_buf[s->pending++] = (c);}
543
544
545 #define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
546 /* Minimum amount of lookahead, except at the end of the input file.
547 * See deflate.c for comments about the MIN_MATCH+1.
548 */
549
550 #define MAX_DIST(s) ((s)->w_size-MIN_LOOKAHEAD)
551 /* In order to simplify the code, particularly on 16 bit machines, match
552 * distances are limited to MAX_DIST instead of WSIZE.
553 */
554
555 /* in trees.c */
556 void _tr_init OF((deflate_state *s));
557 int _tr_tally OF((deflate_state *s, unsigned dist, unsigned lc));
558 void _tr_flush_block OF((deflate_state *s, charf *buf, ulg stored_len,
559 int eof));
560 void _tr_align OF((deflate_state *s));
561 void _tr_stored_block OF((deflate_state *s, charf *buf, ulg stored_len,
562 int eof));
563
564 #define d_code(dist) \
565 ((dist) < 256 ? _dist_code[dist] : _dist_code[256+((dist)>>7)])
566 /* Mapping from a distance to a distance code. dist is the distance - 1 and
567 * must not have side effects. _dist_code[256] and _dist_code[257] are never
568 * used.
569 */
570
571 #ifndef DEBUG_ZLIB
572 /* Inline versions of _tr_tally for speed: */
573
574 #if defined(GEN_TREES_H) || !defined(STDC)
575 extern uch _length_code[];
576 extern uch _dist_code[];
577 #else
578 extern const uch _length_code[];
579 extern const uch _dist_code[];
580 #endif
581
582 # define _tr_tally_lit(s, c, flush) \
583 { uch cc = (c); \
584 s->d_buf[s->last_lit] = 0; \
585 s->l_buf[s->last_lit++] = cc; \
586 s->dyn_ltree[cc].Freq++; \
587 flush = (s->last_lit == s->lit_bufsize-1); \
588 }
589 # define _tr_tally_dist(s, distance, length, flush) \
590 { uch len = (length); \
591 ush dist = (distance); \
592 s->d_buf[s->last_lit] = dist; \
593 s->l_buf[s->last_lit++] = len; \
594 dist--; \
595 s->dyn_ltree[_length_code[len]+LITERALS+1].Freq++; \
596 s->dyn_dtree[d_code(dist)].Freq++; \
597 flush = (s->last_lit == s->lit_bufsize-1); \
598 }
599 #else
600 # define _tr_tally_lit(s, c, flush) flush = _tr_tally(s, 0, c)
601 # define _tr_tally_dist(s, distance, length, flush) \
602 flush = _tr_tally(s, distance, length)
603 #endif
604
605 #endif
606 /* --- deflate.h */
607
608 /* +++ deflate.c */
609 /* deflate.c -- compress data using the deflation algorithm
610 * Copyright (C) 1995-2002 Jean-loup Gailly.
611 * For conditions of distribution and use, see copyright notice in zlib.h
612 */
613
614 /*
615 * ALGORITHM
616 *
617 * The "deflation" process depends on being able to identify portions
618 * of the input text which are identical to earlier input (within a
619 * sliding window trailing behind the input currently being processed).
620 *
621 * The most straightforward technique turns out to be the fastest for
622 * most input files: try all possible matches and select the longest.
623 * The key feature of this algorithm is that insertions into the string
624 * dictionary are very simple and thus fast, and deletions are avoided
625 * completely. Insertions are performed at each input character, whereas
626 * string matches are performed only when the previous match ends. So it
627 * is preferable to spend more time in matches to allow very fast string
628 * insertions and avoid deletions. The matching algorithm for small
629 * strings is inspired from that of Rabin & Karp. A brute force approach
630 * is used to find longer strings when a small match has been found.
631 * A similar algorithm is used in comic (by Jan-Mark Wams) and freeze
632 * (by Leonid Broukhis).
633 * A previous version of this file used a more sophisticated algorithm
634 * (by Fiala and Greene) which is guaranteed to run in linear amortized
635 * time, but has a larger average cost, uses more memory and is patented.
636 * However the F&G algorithm may be faster for some highly redundant
637 * files if the parameter max_chain_length (described below) is too large.
638 *
639 * ACKNOWLEDGEMENTS
640 *
641 * The idea of lazy evaluation of matches is due to Jan-Mark Wams, and
642 * I found it in 'freeze' written by Leonid Broukhis.
643 * Thanks to many people for bug reports and testing.
644 *
645 * REFERENCES
646 *
647 * Deutsch, L.P.,"DEFLATE Compressed Data Format Specification".
648 * Available in ftp://ds.internic.net/rfc/rfc1951.txt
649 *
650 * A description of the Rabin and Karp algorithm is given in the book
651 * "Algorithms" by R. Sedgewick, Addison-Wesley, p252.
652 *
653 * Fiala,E.R., and Greene,D.H.
654 * Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595
655 *
656 */
657
658 /* @(#) $Id: zlib.c,v 1.10 2004/07/29 19:17:20 lindak Exp $ */
659
660 /* #include "deflate.h" */
661
662 const char deflate_copyright[] =
663 " deflate 1.1.4 Copyright 1995-2002 Jean-loup Gailly ";
664 /*
665 If you use the zlib library in a product, an acknowledgment is welcome
666 in the documentation of your product. If for some reason you cannot
667 include such an acknowledgment, I would appreciate that you keep this
668 copyright string in the executable of your product.
669 */
670
671 /* ===========================================================================
672 * Function prototypes.
673 */
674 typedef enum {
675 need_more, /* block not completed, need more input or more output */
676 block_done, /* block flush performed */
677 finish_started, /* finish started, need only more output at next deflate */
678 finish_done /* finish done, accept no more input or output */
679 } block_state;
680
681 typedef block_state (*compress_func) OF((deflate_state *s, int flush));
682 /* Compression function. Returns the block state after the call. */
683
684 local void fill_window OF((deflate_state *s));
685 local block_state deflate_stored OF((deflate_state *s, int flush));
686 local block_state deflate_fast OF((deflate_state *s, int flush));
687 local block_state deflate_slow OF((deflate_state *s, int flush));
688 local void lm_init OF((deflate_state *s));
689 local void putShortMSB OF((deflate_state *s, uInt b));
690 local void flush_pending OF((z_streamp strm));
691 local int read_buf OF((z_streamp strm, Bytef *buf, unsigned size));
692 #ifdef ASMV
693 void match_init OF((void)); /* asm code initialization */
694 uInt longest_match OF((deflate_state *s, IPos cur_match));
695 #else
696 local uInt longest_match OF((deflate_state *s, IPos cur_match));
697 #endif
698
699 #ifdef DEBUG_ZLIB
700 local void check_match OF((deflate_state *s, IPos start, IPos match,
701 int length));
702 #endif
703
704 /* ===========================================================================
705 * Local data
706 */
707
708 #define NIL 0
709 /* Tail of hash chains */
710
711 #ifndef TOO_FAR
712 # define TOO_FAR 4096
713 #endif
714 /* Matches of length 3 are discarded if their distance exceeds TOO_FAR */
715
716 #define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
717 /* Minimum amount of lookahead, except at the end of the input file.
718 * See deflate.c for comments about the MIN_MATCH+1.
719 */
720
721 /* Values for max_lazy_match, good_match and max_chain_length, depending on
722 * the desired pack level (0..9). The values given below have been tuned to
723 * exclude worst case performance for pathological files. Better values may be
724 * found for specific files.
725 */
726 typedef struct config_s {
727 ush good_length; /* reduce lazy search above this match length */
728 ush max_lazy; /* do not perform lazy search above this match length */
729 ush nice_length; /* quit search above this match length */
730 ush max_chain;
731 compress_func func;
732 } config;
733
734 local const config configuration_table[10] = {
735 /* good lazy nice chain */
736 /* 0 */ {0, 0, 0, 0, deflate_stored}, /* store only */
737 /* 1 */ {4, 4, 8, 4, deflate_fast}, /* maximum speed, no lazy matches */
738 /* 2 */ {4, 5, 16, 8, deflate_fast},
739 /* 3 */ {4, 6, 32, 32, deflate_fast},
740
741 /* 4 */ {4, 4, 16, 16, deflate_slow}, /* lazy matches */
742 /* 5 */ {8, 16, 32, 32, deflate_slow},
743 /* 6 */ {8, 16, 128, 128, deflate_slow},
744 /* 7 */ {8, 32, 128, 256, deflate_slow},
745 /* 8 */ {32, 128, 258, 1024, deflate_slow},
746 /* 9 */ {32, 258, 258, 4096, deflate_slow}}; /* maximum compression */
747
748 /* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4
749 * For deflate_fast() (levels <= 3) good is ignored and lazy has a different
750 * meaning.
751 */
752
753 #define EQUAL 0
754 /* result of memcmp for equal strings */
755
756 #ifndef NO_DUMMY_DECL
757 struct static_tree_desc_s {int dummy;}; /* for buggy compilers */
758 #endif
759
760 /* ===========================================================================
761 * Update a hash value with the given input byte
762 * IN assertion: all calls to to UPDATE_HASH are made with consecutive
763 * input characters, so that a running hash key can be computed from the
764 * previous key instead of complete recalculation each time.
765 */
766 #define UPDATE_HASH(s,h,c) (h = (((h)<<s->hash_shift) ^ (c)) & s->hash_mask)
767
768
769 /* ===========================================================================
770 * Insert string str in the dictionary and set match_head to the previous head
771 * of the hash chain (the most recent string with same hash key). Return
772 * the previous length of the hash chain.
773 * If this file is compiled with -DFASTEST, the compression level is forced
774 * to 1, and no hash chains are maintained.
775 * IN assertion: all calls to to INSERT_STRING are made with consecutive
776 * input characters and the first MIN_MATCH bytes of str are valid
777 * (except for the last MIN_MATCH-1 bytes of the input file).
778 */
779 #ifdef FASTEST
780 #define INSERT_STRING(s, str, match_head) \
781 (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \
782 match_head = s->head[s->ins_h], \
783 s->head[s->ins_h] = (Pos)(str))
784 #else
785 #define INSERT_STRING(s, str, match_head) \
786 (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \
787 s->prev[(str) & s->w_mask] = match_head = s->head[s->ins_h], \
788 s->head[s->ins_h] = (Pos)(str))
789 #endif
790
791 /* ===========================================================================
792 * Initialize the hash table (avoiding 64K overflow for 16 bit systems).
793 * prev[] will be initialized on the fly.
794 */
795 #define CLEAR_HASH(s) \
796 s->head[s->hash_size-1] = NIL; \
797 zmemzero((Bytef *)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head));
798
799 /* ========================================================================= */
800 int ZEXPORT deflateInit_(strm, level, version, stream_size)
801 z_streamp strm;
802 int level;
803 const char *version;
804 int stream_size;
805 {
806 return deflateInit2_(strm, level, Z_DEFLATED, MAX_WBITS, DEF_MEM_LEVEL,
807 Z_DEFAULT_STRATEGY, version, stream_size);
808 /* To do: ignore strm->next_in if we use it as window */
809 }
810
811 /* ========================================================================= */
812 int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
813 version, stream_size)
814 z_streamp strm;
815 int level;
816 int method;
817 int windowBits;
818 int memLevel;
819 int strategy;
820 const char *version;
821 int stream_size;
822 {
823 deflate_state *s;
824 int noheader = 0;
825 static const char* my_version = ZLIB_VERSION;
826
827 ushf *overlay;
828 /* We overlay pending_buf and d_buf+l_buf. This works since the average
829 * output size for (length,distance) codes is <= 24 bits.
830 */
831
832 if (version == Z_NULL || version[0] != my_version[0] ||
833 stream_size != sizeof(z_stream)) {
834 return Z_VERSION_ERROR;
835 }
836 if (strm == Z_NULL) return Z_STREAM_ERROR;
837
838 strm->msg = Z_NULL;
839 #ifndef NO_ZCFUNCS
840 if (strm->zalloc == Z_NULL) {
841 strm->zalloc = zcalloc;
842 strm->opaque = (voidpf)0;
843 }
844 if (strm->zfree == Z_NULL) strm->zfree = zcfree;
845 #endif
846
847 if (level == Z_DEFAULT_COMPRESSION) level = 6;
848 #ifdef FASTEST
849 level = 1;
850 #endif
851
852 if (windowBits < 0) { /* undocumented feature: suppress zlib header */
853 noheader = 1;
854 windowBits = -windowBits;
855 }
856 if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED ||
857 windowBits < 9 || windowBits > 15 || level < 0 || level > 9 ||
858 strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
859 return Z_STREAM_ERROR;
860 }
861 s = (deflate_state *) ZALLOC(strm, 1, sizeof(deflate_state));
862 if (s == Z_NULL) return Z_MEM_ERROR;
863 strm->state = (struct internal_state FAR *)s;
864 s->strm = strm;
865
866 s->noheader = noheader;
867 s->w_bits = windowBits;
868 s->w_size = 1 << s->w_bits;
869 s->w_mask = s->w_size - 1;
870
871 s->hash_bits = memLevel + 7;
872 s->hash_size = 1 << s->hash_bits;
873 s->hash_mask = s->hash_size - 1;
874 s->hash_shift = ((s->hash_bits+MIN_MATCH-1)/MIN_MATCH);
875
876 s->window = (Bytef *) ZALLOC(strm, s->w_size, 2*sizeof(Byte));
877 s->prev = (Posf *) ZALLOC(strm, s->w_size, sizeof(Pos));
878 s->head = (Posf *) ZALLOC(strm, s->hash_size, sizeof(Pos));
879
880 s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */
881
882 overlay = (ushf *) ZALLOC(strm, s->lit_bufsize, sizeof(ush)+2);
883 s->pending_buf = (uchf *) overlay;
884 s->pending_buf_size = (ulg)s->lit_bufsize * (sizeof(ush)+2L);
885
886 if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL ||
887 s->pending_buf == Z_NULL) {
888 strm->msg = (char*)ERR_MSG(Z_MEM_ERROR);
889 deflateEnd (strm);
890 return Z_MEM_ERROR;
891 }
892 s->d_buf = overlay + s->lit_bufsize/sizeof(ush);
893 s->l_buf = s->pending_buf + (1+sizeof(ush))*s->lit_bufsize;
894
895 s->level = level;
896 s->strategy = strategy;
897 s->method = (Byte)method;
898
899 return deflateReset(strm);
900 }
901
902 /* ========================================================================= */
903 int ZEXPORT deflateSetDictionary (strm, dictionary, dictLength)
904 z_streamp strm;
905 const Bytef *dictionary;
906 uInt dictLength;
907 {
908 deflate_state *s;
909 uInt length = dictLength;
910 uInt n;
911 IPos hash_head = 0;
912
913 if (strm == Z_NULL || strm->state == Z_NULL || dictionary == Z_NULL ||
914 ((deflate_state*)strm->state)->status != INIT_STATE) return Z_STREAM_ERROR;
915
916 s = (deflate_state*)strm->state;
917 strm->adler = adler32(strm->adler, dictionary, dictLength);
918
919 if (length < MIN_MATCH) return Z_OK;
920 if (length > MAX_DIST(s)) {
921 length = MAX_DIST(s);
922 #ifndef USE_DICT_HEAD
923 dictionary += dictLength - length; /* use the tail of the dictionary */
924 #endif
925 }
926 zmemcpy(s->window, dictionary, length);
927 s->strstart = length;
928 s->block_start = (long)length;
929
930 /* Insert all strings in the hash table (except for the last two bytes).
931 * s->lookahead stays null, so s->ins_h will be recomputed at the next
932 * call of fill_window.
933 */
934 s->ins_h = s->window[0];
935 UPDATE_HASH(s, s->ins_h, s->window[1]);
936 for (n = 0; n <= length - MIN_MATCH; n++) {
937 INSERT_STRING(s, n, hash_head);
938 }
939 if (hash_head) hash_head = 0; /* to make compiler happy */
940 return Z_OK;
941 }
942
943 /* ========================================================================= */
944 int ZEXPORT deflateReset (strm)
945 z_streamp strm;
946 {
947 deflate_state *s;
948
949 if (strm == Z_NULL || strm->state == Z_NULL ||
950 strm->zalloc == Z_NULL || strm->zfree == Z_NULL) return Z_STREAM_ERROR;
951
952 strm->total_in = strm->total_out = 0;
953 strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */
954 strm->data_type = Z_UNKNOWN;
955
956 s = (deflate_state *)strm->state;
957 s->pending = 0;
958 s->pending_out = s->pending_buf;
959
960 if (s->noheader < 0) {
961 s->noheader = 0; /* was set to -1 by deflate(..., Z_FINISH); */
962 }
963 s->status = s->noheader ? BUSY_STATE : INIT_STATE;
964 strm->adler = 1;
965 s->last_flush = Z_NO_FLUSH;
966
967 _tr_init(s);
968 lm_init(s);
969
970 return Z_OK;
971 }
972
973 /* ========================================================================= */
974 int ZEXPORT deflateParams(strm, level, strategy)
975 z_streamp strm;
976 int level;
977 int strategy;
978 {
979 deflate_state *s;
980 compress_func func;
981 int err = Z_OK;
982
983 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
984 s = (deflate_state*)strm->state;
985
986 if (level == Z_DEFAULT_COMPRESSION) {
987 level = 6;
988 }
989 if (level < 0 || level > 9 || strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
990 return Z_STREAM_ERROR;
991 }
992 func = configuration_table[s->level].func;
993
994 if (func != configuration_table[level].func && strm->total_in != 0) {
995 /* Flush the last buffer: */
996 err = deflate(strm, Z_PARTIAL_FLUSH);
997 }
998 if (s->level != level) {
999 s->level = level;
1000 s->max_lazy_match = configuration_table[level].max_lazy;
1001 s->good_match = configuration_table[level].good_length;
1002 s->nice_match = configuration_table[level].nice_length;
1003 s->max_chain_length = configuration_table[level].max_chain;
1004 }
1005 s->strategy = strategy;
1006 return err;
1007 }
1008
1009 /* =========================================================================
1010 * Put a short in the pending buffer. The 16-bit value is put in MSB order.
1011 * IN assertion: the stream state is correct and there is enough room in
1012 * pending_buf.
1013 */
1014 local void putShortMSB (s, b)
1015 deflate_state *s;
1016 uInt b;
1017 {
1018 put_byte(s, (Byte)(b >> 8));
1019 put_byte(s, (Byte)(b & 0xff));
1020 }
1021
1022 /* =========================================================================
1023 * Flush as much pending output as possible. All deflate() output goes
1024 * through this function so some applications may wish to modify it
1025 * to avoid allocating a large strm->next_out buffer and copying into it.
1026 * (See also read_buf()).
1027 */
1028 local void flush_pending(strm)
1029 z_streamp strm;
1030 {
1031 deflate_state* s = (deflate_state*)strm->state;
1032 unsigned len = s->pending;
1033
1034 if (len > strm->avail_out) len = strm->avail_out;
1035 if (len == 0) return;
1036
1037 zmemcpy(strm->next_out, s->pending_out, len);
1038 strm->next_out += len;
1039 s->pending_out += len;
1040 strm->total_out += len;
1041 strm->avail_out -= len;
1042 s->pending -= len;
1043 if (s->pending == 0) {
1044 s->pending_out = s->pending_buf;
1045 }
1046 }
1047
1048 /* ========================================================================= */
1049 int ZEXPORT deflate (strm, flush)
1050 z_streamp strm;
1051 int flush;
1052 {
1053 int old_flush; /* value of flush param for previous deflate call */
1054 deflate_state *s;
1055
1056 if (strm == Z_NULL || strm->state == Z_NULL ||
1057 flush > Z_FINISH || flush < 0) {
1058 return Z_STREAM_ERROR;
1059 }
1060 s = (deflate_state*)strm->state;
1061
1062 if (strm->next_out == Z_NULL ||
1063 (strm->next_in == Z_NULL && strm->avail_in != 0) ||
1064 (s->status == FINISH_STATE && flush != Z_FINISH)) {
1065 ERR_RETURN(strm, Z_STREAM_ERROR);
1066 }
1067 if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR);
1068
1069 s->strm = strm; /* just in case */
1070 old_flush = s->last_flush;
1071 s->last_flush = flush;
1072
1073 /* Write the zlib header */
1074 if (s->status == INIT_STATE) {
1075
1076 uInt header = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8;
1077 uInt level_flags = (s->level-1) >> 1;
1078
1079 if (level_flags > 3) level_flags = 3;
1080 header |= (level_flags << 6);
1081 if (s->strstart != 0) header |= PRESET_DICT;
1082 header += 31 - (header % 31);
1083
1084 s->status = BUSY_STATE;
1085 putShortMSB(s, header);
1086
1087 /* Save the adler32 of the preset dictionary: */
1088 if (s->strstart != 0) {
1089 putShortMSB(s, (uInt)(strm->adler >> 16));
1090 putShortMSB(s, (uInt)(strm->adler & 0xffff));
1091 }
1092 strm->adler = 1L;
1093 }
1094
1095 /* Flush as much pending output as possible */
1096 if (s->pending != 0) {
1097 flush_pending(strm);
1098 if (strm->avail_out == 0) {
1099 /* Since avail_out is 0, deflate will be called again with
1100 * more output space, but possibly with both pending and
1101 * avail_in equal to zero. There won't be anything to do,
1102 * but this is not an error situation so make sure we
1103 * return OK instead of BUF_ERROR at next call of deflate:
1104 */
1105 s->last_flush = -1;
1106 return Z_OK;
1107 }
1108
1109 /* Make sure there is something to do and avoid duplicate consecutive
1110 * flushes. For repeated and useless calls with Z_FINISH, we keep
1111 * returning Z_STREAM_END instead of Z_BUFF_ERROR.
1112 */
1113 } else if (strm->avail_in == 0 && flush <= old_flush &&
1114 flush != Z_FINISH) {
1115 ERR_RETURN(strm, Z_BUF_ERROR);
1116 }
1117
1118 /* User must not provide more input after the first FINISH: */
1119 if (s->status == FINISH_STATE && strm->avail_in != 0) {
1120 ERR_RETURN(strm, Z_BUF_ERROR);
1121 }
1122
1123 /* Start a new block or continue the current one.
1124 */
1125 if (strm->avail_in != 0 || s->lookahead != 0 ||
1126 (flush != Z_NO_FLUSH && s->status != FINISH_STATE)) {
1127 block_state bstate;
1128
1129 bstate = (*(configuration_table[s->level].func))(s, flush);
1130
1131 if (bstate == finish_started || bstate == finish_done) {
1132 s->status = FINISH_STATE;
1133 }
1134 if (bstate == need_more || bstate == finish_started) {
1135 if (strm->avail_out == 0) {
1136 s->last_flush = -1; /* avoid BUF_ERROR next call, see above */
1137 }
1138 return Z_OK;
1139 /* If flush != Z_NO_FLUSH && avail_out == 0, the next call
1140 * of deflate should use the same flush parameter to make sure
1141 * that the flush is complete. So we don't have to output an
1142 * empty block here, this will be done at next call. This also
1143 * ensures that for a very small output buffer, we emit at most
1144 * one empty block.
1145 */
1146 }
1147 if (bstate == block_done) {
1148 if (flush == Z_PARTIAL_FLUSH) {
1149 _tr_align(s);
1150 } else { /* FULL_FLUSH or SYNC_FLUSH */
1151 _tr_stored_block(s, (char*)0, 0L, 0);
1152 /* For a full flush, this empty block will be recognized
1153 * as a special marker by inflate_sync().
1154 */
1155 if (flush == Z_FULL_FLUSH) {
1156 CLEAR_HASH(s); /* forget history */
1157 }
1158 }
1159 flush_pending(strm);
1160 if (strm->avail_out == 0) {
1161 s->last_flush = -1; /* avoid BUF_ERROR at next call, see above */
1162 return Z_OK;
1163 }
1164 }
1165 }
1166 Assert(strm->avail_out > 0, "bug2");
1167
1168 if (flush != Z_FINISH) return Z_OK;
1169 if (s->noheader) return Z_STREAM_END;
1170
1171 /* Write the zlib trailer (adler32) */
1172 putShortMSB(s, (uInt)(strm->adler >> 16));
1173 putShortMSB(s, (uInt)(strm->adler & 0xffff));
1174 flush_pending(strm);
1175 /* If avail_out is zero, the application will call deflate again
1176 * to flush the rest.
1177 */
1178 s->noheader = -1; /* write the trailer only once! */
1179 return s->pending != 0 ? Z_OK : Z_STREAM_END;
1180 }
1181
1182 /* ========================================================================= */
1183 int ZEXPORT deflateEnd (strm)
1184 z_streamp strm;
1185 {
1186 deflate_state* s;
1187 int status;
1188
1189 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
1190
1191 s = (deflate_state*)strm->state;
1192 status = s->status;
1193 if (status != INIT_STATE && status != BUSY_STATE &&
1194 status != FINISH_STATE) {
1195 return Z_STREAM_ERROR;
1196 }
1197
1198 /* Deallocate in reverse order of allocations: */
1199 TRY_FREE(strm, s->pending_buf);
1200 TRY_FREE(strm, s->head);
1201 TRY_FREE(strm, s->prev);
1202 TRY_FREE(strm, s->window);
1203
1204 ZFREE(strm, s);
1205 strm->state = Z_NULL;
1206
1207 return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK;
1208 }
1209
1210 /* =========================================================================
1211 * Copy the source state to the destination state.
1212 * To simplify the source, this is not supported for 16-bit MSDOS (which
1213 * doesn't have enough memory anyway to duplicate compression states).
1214 */
1215 int ZEXPORT deflateCopy (dest, source)
1216 z_streamp dest;
1217 z_streamp source;
1218 {
1219 #ifdef MAXSEG_64K
1220 return Z_STREAM_ERROR;
1221 #else
1222 deflate_state *ds;
1223 deflate_state *ss;
1224 ushf *overlay;
1225
1226
1227 if (source == Z_NULL || dest == Z_NULL || source->state == Z_NULL) {
1228 return Z_STREAM_ERROR;
1229 }
1230
1231 ss = (deflate_state*)source->state;
1232
1233 *dest = *source;
1234
1235 ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state));
1236 if (ds == Z_NULL) return Z_MEM_ERROR;
1237 dest->state = (struct internal_state FAR *) ds;
1238 *ds = *ss;
1239 ds->strm = dest;
1240
1241 ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte));
1242 ds->prev = (Posf *) ZALLOC(dest, ds->w_size, sizeof(Pos));
1243 ds->head = (Posf *) ZALLOC(dest, ds->hash_size, sizeof(Pos));
1244 overlay = (ushf *) ZALLOC(dest, ds->lit_bufsize, sizeof(ush)+2);
1245 ds->pending_buf = (uchf *) overlay;
1246
1247 if (ds->window == Z_NULL || ds->prev == Z_NULL || ds->head == Z_NULL ||
1248 ds->pending_buf == Z_NULL) {
1249 deflateEnd (dest);
1250 return Z_MEM_ERROR;
1251 }
1252 /* following zmemcpy do not work for 16-bit MSDOS */
1253 zmemcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte));
1254 zmemcpy(ds->prev, ss->prev, ds->w_size * sizeof(Pos));
1255 zmemcpy(ds->head, ss->head, ds->hash_size * sizeof(Pos));
1256 zmemcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size);
1257
1258 ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf);
1259 ds->d_buf = overlay + ds->lit_bufsize/sizeof(ush);
1260 ds->l_buf = ds->pending_buf + (1+sizeof(ush))*ds->lit_bufsize;
1261
1262 ds->l_desc.dyn_tree = ds->dyn_ltree;
1263 ds->d_desc.dyn_tree = ds->dyn_dtree;
1264 ds->bl_desc.dyn_tree = ds->bl_tree;
1265
1266 return Z_OK;
1267 #endif
1268 }
1269
1270 /* ===========================================================================
1271 * Read a new buffer from the current input stream, update the adler32
1272 * and total number of bytes read. All deflate() input goes through
1273 * this function so some applications may wish to modify it to avoid
1274 * allocating a large strm->next_in buffer and copying from it.
1275 * (See also flush_pending()).
1276 */
1277 local int read_buf(strm, buf, size)
1278 z_streamp strm;
1279 Bytef *buf;
1280 unsigned size;
1281 {
1282 unsigned len = strm->avail_in;
1283
1284 if (len > size) len = size;
1285 if (len == 0) return 0;
1286
1287 strm->avail_in -= len;
1288
1289 if (!((deflate_state*)strm->state)->noheader) {
1290 strm->adler = adler32(strm->adler, strm->next_in, len);
1291 }
1292 zmemcpy(buf, strm->next_in, len);
1293 strm->next_in += len;
1294 strm->total_in += len;
1295
1296 return (int)len;
1297 }
1298
1299 /* ===========================================================================
1300 * Initialize the "longest match" routines for a new zlib stream
1301 */
1302 local void lm_init (s)
1303 deflate_state *s;
1304 {
1305 s->window_size = (ulg)2L*s->w_size;
1306
1307 CLEAR_HASH(s);
1308
1309 /* Set the default configuration parameters:
1310 */
1311 s->max_lazy_match = configuration_table[s->level].max_lazy;
1312 s->good_match = configuration_table[s->level].good_length;
1313 s->nice_match = configuration_table[s->level].nice_length;
1314 s->max_chain_length = configuration_table[s->level].max_chain;
1315
1316 s->strstart = 0;
1317 s->block_start = 0L;
1318 s->lookahead = 0;
1319 s->match_length = s->prev_length = MIN_MATCH-1;
1320 s->match_available = 0;
1321 s->ins_h = 0;
1322 #ifdef ASMV
1323 match_init(); /* initialize the asm code */
1324 #endif
1325 }
1326
1327 /* ===========================================================================
1328 * Set match_start to the longest match starting at the given string and
1329 * return its length. Matches shorter or equal to prev_length are discarded,
1330 * in which case the result is equal to prev_length and match_start is
1331 * garbage.
1332 * IN assertions: cur_match is the head of the hash chain for the current
1333 * string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1
1334 * OUT assertion: the match length is not greater than s->lookahead.
1335 */
1336 #ifndef ASMV
1337 /* For 80x86 and 680x0, an optimized version will be provided in match.asm or
1338 * match.S. The code will be functionally equivalent.
1339 */
1340 #ifndef FASTEST
1341 local uInt longest_match(s, cur_match)
1342 deflate_state *s;
1343 IPos cur_match; /* current match */
1344 {
1345 unsigned chain_length = s->max_chain_length;/* max hash chain length */
1346 register Bytef *scan = s->window + s->strstart; /* current string */
1347 register Bytef *match; /* matched string */
1348 register int len; /* length of current match */
1349 int best_len = s->prev_length; /* best match length so far */
1350 int nice_match = s->nice_match; /* stop if match long enough */
1351 IPos limit = s->strstart > (IPos)MAX_DIST(s) ?
1352 s->strstart - (IPos)MAX_DIST(s) : NIL;
1353 /* Stop when cur_match becomes <= limit. To simplify the code,
1354 * we prevent matches with the string of window index 0.
1355 */
1356 Posf *prev = s->prev;
1357 uInt wmask = s->w_mask;
1358
1359 #ifdef UNALIGNED_OK
1360 /* Compare two bytes at a time. Note: this is not always beneficial.
1361 * Try with and without -DUNALIGNED_OK to check.
1362 */
1363 register Bytef *strend = s->window + s->strstart + MAX_MATCH - 1;
1364 register ush scan_start = *(ushf*)scan;
1365 register ush scan_end = *(ushf*)(scan+best_len-1);
1366 #else
1367 register Bytef *strend = s->window + s->strstart + MAX_MATCH;
1368 register Byte scan_end1 = scan[best_len-1];
1369 register Byte scan_end = scan[best_len];
1370 #endif
1371
1372 /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
1373 * It is easy to get rid of this optimization if necessary.
1374 */
1375 Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");
1376
1377 /* Do not waste too much time if we already have a good match: */
1378 if (s->prev_length >= s->good_match) {
1379 chain_length >>= 2;
1380 }
1381 /* Do not look for matches beyond the end of the input. This is necessary
1382 * to make deflate deterministic.
1383 */
1384 if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;
1385
1386 Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
1387
1388 do {
1389 Assert(cur_match < s->strstart, "no future");
1390 match = s->window + cur_match;
1391
1392 /* Skip to next match if the match length cannot increase
1393 * or if the match length is less than 2:
1394 */
1395 #if (defined(UNALIGNED_OK) && MAX_MATCH == 258)
1396 /* This code assumes sizeof(unsigned short) == 2. Do not use
1397 * UNALIGNED_OK if your compiler uses a different size.
1398 */
1399 if (*(ushf*)(match+best_len-1) != scan_end ||
1400 *(ushf*)match != scan_start) continue;
1401
1402 /* It is not necessary to compare scan[2] and match[2] since they are
1403 * always equal when the other bytes match, given that the hash keys
1404 * are equal and that HASH_BITS >= 8. Compare 2 bytes at a time at
1405 * strstart+3, +5, ... up to strstart+257. We check for insufficient
1406 * lookahead only every 4th comparison; the 128th check will be made
1407 * at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is
1408 * necessary to put more guard bytes at the end of the window, or
1409 * to check more often for insufficient lookahead.
1410 */
1411 Assert(scan[2] == match[2], "scan[2]?");
1412 scan++, match++;
1413 do {
1414 } while (*(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1415 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1416 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1417 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1418 scan < strend);
1419 /* The funny "do {}" generates better code on most compilers */
1420
1421 /* Here, scan <= window+strstart+257 */
1422 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1423 if (*scan == *match) scan++;
1424
1425 len = (MAX_MATCH - 1) - (int)(strend-scan);
1426 scan = strend - (MAX_MATCH-1);
1427
1428 #else /* UNALIGNED_OK */
1429
1430 if (match[best_len] != scan_end ||
1431 match[best_len-1] != scan_end1 ||
1432 *match != *scan ||
1433 *++match != scan[1]) continue;
1434
1435 /* The check at best_len-1 can be removed because it will be made
1436 * again later. (This heuristic is not always a win.)
1437 * It is not necessary to compare scan[2] and match[2] since they
1438 * are always equal when the other bytes match, given that
1439 * the hash keys are equal and that HASH_BITS >= 8.
1440 */
1441 scan += 2, match++;
1442 Assert(*scan == *match, "match[2]?");
1443
1444 /* We check for insufficient lookahead only every 8th comparison;
1445 * the 256th check will be made at strstart+258.
1446 */
1447 do {
1448 } while (*++scan == *++match && *++scan == *++match &&
1449 *++scan == *++match && *++scan == *++match &&
1450 *++scan == *++match && *++scan == *++match &&
1451 *++scan == *++match && *++scan == *++match &&
1452 scan < strend);
1453
1454 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1455
1456 len = MAX_MATCH - (int)(strend - scan);
1457 scan = strend - MAX_MATCH;
1458
1459 #endif /* UNALIGNED_OK */
1460
1461 if (len > best_len) {
1462 s->match_start = cur_match;
1463 best_len = len;
1464 if (len >= nice_match) break;
1465 #ifdef UNALIGNED_OK
1466 scan_end = *(ushf*)(scan+best_len-1);
1467 #else
1468 scan_end1 = scan[best_len-1];
1469 scan_end = scan[best_len];
1470 #endif
1471 }
1472 } while ((cur_match = prev[cur_match & wmask]) > limit
1473 && --chain_length != 0);
1474
1475 if ((uInt)best_len <= s->lookahead) return (uInt)best_len;
1476 return s->lookahead;
1477 }
1478
1479 #else /* FASTEST */
1480 /* ---------------------------------------------------------------------------
1481 * Optimized version for level == 1 only
1482 */
1483 local uInt longest_match(s, cur_match)
1484 deflate_state *s;
1485 IPos cur_match; /* current match */
1486 {
1487 register Bytef *scan = s->window + s->strstart; /* current string */
1488 register Bytef *match; /* matched string */
1489 register int len; /* length of current match */
1490 register Bytef *strend = s->window + s->strstart + MAX_MATCH;
1491
1492 /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
1493 * It is easy to get rid of this optimization if necessary.
1494 */
1495 Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");
1496
1497 Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
1498
1499 Assert(cur_match < s->strstart, "no future");
1500
1501 match = s->window + cur_match;
1502
1503 /* Return failure if the match length is less than 2:
1504 */
1505 if (match[0] != scan[0] || match[1] != scan[1]) return MIN_MATCH-1;
1506
1507 /* The check at best_len-1 can be removed because it will be made
1508 * again later. (This heuristic is not always a win.)
1509 * It is not necessary to compare scan[2] and match[2] since they
1510 * are always equal when the other bytes match, given that
1511 * the hash keys are equal and that HASH_BITS >= 8.
1512 */
1513 scan += 2, match += 2;
1514 Assert(*scan == *match, "match[2]?");
1515
1516 /* We check for insufficient lookahead only every 8th comparison;
1517 * the 256th check will be made at strstart+258.
1518 */
1519 do {
1520 } while (*++scan == *++match && *++scan == *++match &&
1521 *++scan == *++match && *++scan == *++match &&
1522 *++scan == *++match && *++scan == *++match &&
1523 *++scan == *++match && *++scan == *++match &&
1524 scan < strend);
1525
1526 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1527
1528 len = MAX_MATCH - (int)(strend - scan);
1529
1530 if (len < MIN_MATCH) return MIN_MATCH - 1;
1531
1532 s->match_start = cur_match;
1533 return len <= s->lookahead ? len : s->lookahead;
1534 }
1535 #endif /* FASTEST */
1536 #endif /* ASMV */
1537
1538 #ifdef DEBUG_ZLIB
1539 /* ===========================================================================
1540 * Check that the match at match_start is indeed a match.
1541 */
1542 local void check_match(s, start, match, length)
1543 deflate_state *s;
1544 IPos start, match;
1545 int length;
1546 {
1547 /* check that the match is indeed a match */
1548 if (zmemcmp(s->window + match,
1549 s->window + start, length) != EQUAL) {
1550 fprintf(stderr, " start %u, match %u, length %d\n",
1551 start, match, length);
1552 do {
1553 fprintf(stderr, "%c%c", s->window[match++], s->window[start++]);
1554 } while (--length != 0);
1555 z_error("invalid match");
1556 }
1557 if (z_verbose > 1) {
1558 fprintf(stderr,"\\[%d,%d]", start-match, length);
1559 do { putc(s->window[start++], stderr); } while (--length != 0);
1560 }
1561 }
1562 #else
1563 # define check_match(s, start, match, length)
1564 #endif
1565
1566 /* ===========================================================================
1567 * Fill the window when the lookahead becomes insufficient.
1568 * Updates strstart and lookahead.
1569 *
1570 * IN assertion: lookahead < MIN_LOOKAHEAD
1571 * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD
1572 * At least one byte has been read, or avail_in == 0; reads are
1573 * performed for at least two bytes (required for the zip translate_eol
1574 * option -- not supported here).
1575 */
1576 local void fill_window(s)
1577 deflate_state *s;
1578 {
1579 register unsigned n, m;
1580 register Posf *p;
1581 unsigned more; /* Amount of free space at the end of the window. */
1582 uInt wsize = s->w_size;
1583
1584 do {
1585 more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart);
1586
1587 /* Deal with !@#$% 64K limit: */
1588 if (more == 0 && s->strstart == 0 && s->lookahead == 0) {
1589 more = wsize;
1590
1591 } else if (more == (unsigned)(-1)) {
1592 /* Very unlikely, but possible on 16 bit machine if strstart == 0
1593 * and lookahead == 1 (input done one byte at time)
1594 */
1595 more--;
1596
1597 /* If the window is almost full and there is insufficient lookahead,
1598 * move the upper half to the lower one to make room in the upper half.
1599 */
1600 } else if (s->strstart >= wsize+MAX_DIST(s)) {
1601
1602 zmemcpy(s->window, s->window+wsize, (unsigned)wsize);
1603 s->match_start -= wsize;
1604 s->strstart -= wsize; /* we now have strstart >= MAX_DIST */
1605 s->block_start -= (long) wsize;
1606
1607 /* Slide the hash table (could be avoided with 32 bit values
1608 at the expense of memory usage). We slide even when level == 0
1609 to keep the hash table consistent if we switch back to level > 0
1610 later. (Using level 0 permanently is not an optimal usage of
1611 zlib, so we don't care about this pathological case.)
1612 */
1613 n = s->hash_size;
1614 p = &s->head[n];
1615 do {
1616 m = *--p;
1617 *p = (Pos)(m >= wsize ? m-wsize : NIL);
1618 } while (--n);
1619
1620 n = wsize;
1621 #ifndef FASTEST
1622 p = &s->prev[n];
1623 do {
1624 m = *--p;
1625 *p = (Pos)(m >= wsize ? m-wsize : NIL);
1626 /* If n is not on any hash chain, prev[n] is garbage but
1627 * its value will never be used.
1628 */
1629 } while (--n);
1630 #endif
1631 more += wsize;
1632 }
1633 if (s->strm->avail_in == 0) return;
1634
1635 /* If there was no sliding:
1636 * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 &&
1637 * more == window_size - lookahead - strstart
1638 * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1)
1639 * => more >= window_size - 2*WSIZE + 2
1640 * In the BIG_MEM or MMAP case (not yet supported),
1641 * window_size == input_size + MIN_LOOKAHEAD &&
1642 * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD.
1643 * Otherwise, window_size == 2*WSIZE so more >= 2.
1644 * If there was sliding, more >= WSIZE. So in all cases, more >= 2.
1645 */
1646 Assert(more >= 2, "more < 2");
1647
1648 n = read_buf(s->strm, s->window + s->strstart + s->lookahead, more);
1649 s->lookahead += n;
1650
1651 /* Initialize the hash value now that we have some input: */
1652 if (s->lookahead >= MIN_MATCH) {
1653 s->ins_h = s->window[s->strstart];
1654 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
1655 #if MIN_MATCH != 3
1656 Call UPDATE_HASH() MIN_MATCH-3 more times
1657 #endif
1658 }
1659 /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage,
1660 * but this is not important since only literal bytes will be emitted.
1661 */
1662
1663 } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0);
1664 }
1665
1666 /* ===========================================================================
1667 * Flush the current block, with given end-of-file flag.
1668 * IN assertion: strstart is set to the end of the current match.
1669 */
1670 #define FLUSH_BLOCK_ONLY(s, eof) { \
1671 _tr_flush_block(s, (s->block_start >= 0L ? \
1672 (charf *)&s->window[(unsigned)s->block_start] : \
1673 (charf *)Z_NULL), \
1674 (ulg)((long)s->strstart - s->block_start), \
1675 (eof)); \
1676 s->block_start = s->strstart; \
1677 flush_pending(s->strm); \
1678 Tracev((stderr,"[FLUSH]")); \
1679 }
1680
1681 /* Same but force premature exit if necessary. */
1682 #define FLUSH_BLOCK(s, eof) { \
1683 FLUSH_BLOCK_ONLY(s, eof); \
1684 if (s->strm->avail_out == 0) return (eof) ? finish_started : need_more; \
1685 }
1686
1687 /* ===========================================================================
1688 * Copy without compression as much as possible from the input stream, return
1689 * the current block state.
1690 * This function does not insert new strings in the dictionary since
1691 * uncompressible data is probably not useful. This function is used
1692 * only for the level=0 compression option.
1693 * NOTE: this function should be optimized to avoid extra copying from
1694 * window to pending_buf.
1695 */
1696 local block_state deflate_stored(s, flush)
1697 deflate_state *s;
1698 int flush;
1699 {
1700 /* Stored blocks are limited to 0xffff bytes, pending_buf is limited
1701 * to pending_buf_size, and each stored block has a 5 byte header:
1702 */
1703 ulg max_block_size = 0xffff;
1704 ulg max_start;
1705
1706 if (max_block_size > s->pending_buf_size - 5) {
1707 max_block_size = s->pending_buf_size - 5;
1708 }
1709
1710 /* Copy as much as possible from input to output: */
1711 for (;;) {
1712 /* Fill the window as much as possible: */
1713 if (s->lookahead <= 1) {
1714
1715 Assert(s->strstart < s->w_size+MAX_DIST(s) ||
1716 s->block_start >= (long)s->w_size, "slide too late");
1717
1718 fill_window(s);
1719 if (s->lookahead == 0 && flush == Z_NO_FLUSH) return need_more;
1720
1721 if (s->lookahead == 0) break; /* flush the current block */
1722 }
1723 Assert(s->block_start >= 0L, "block gone");
1724
1725 s->strstart += s->lookahead;
1726 s->lookahead = 0;
1727
1728 /* Emit a stored block if pending_buf will be full: */
1729 max_start = s->block_start + max_block_size;
1730 if (s->strstart == 0 || (ulg)s->strstart >= max_start) {
1731 /* strstart == 0 is possible when wraparound on 16-bit machine */
1732 s->lookahead = (uInt)(s->strstart - max_start);
1733 s->strstart = (uInt)max_start;
1734 FLUSH_BLOCK(s, 0);
1735 }
1736 /* Flush if we may have to slide, otherwise block_start may become
1737 * negative and the data will be gone:
1738 */
1739 if (s->strstart - (uInt)s->block_start >= MAX_DIST(s)) {
1740 FLUSH_BLOCK(s, 0);
1741 }
1742 }
1743 FLUSH_BLOCK(s, flush == Z_FINISH);
1744 return flush == Z_FINISH ? finish_done : block_done;
1745 }
1746
1747 /* ===========================================================================
1748 * Compress as much as possible from the input stream, return the current
1749 * block state.
1750 * This function does not perform lazy evaluation of matches and inserts
1751 * new strings in the dictionary only for unmatched strings or for short
1752 * matches. It is used only for the fast compression options.
1753 */
1754 local block_state deflate_fast(s, flush)
1755 deflate_state *s;
1756 int flush;
1757 {
1758 IPos hash_head = NIL; /* head of the hash chain */
1759 int bflush; /* set if current block must be flushed */
1760
1761 for (;;) {
1762 /* Make sure that we always have enough lookahead, except
1763 * at the end of the input file. We need MAX_MATCH bytes
1764 * for the next match, plus MIN_MATCH bytes to insert the
1765 * string following the next match.
1766 */
1767 if (s->lookahead < MIN_LOOKAHEAD) {
1768 fill_window(s);
1769 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
1770 return need_more;
1771 }
1772 if (s->lookahead == 0) break; /* flush the current block */
1773 }
1774
1775 /* Insert the string window[strstart .. strstart+2] in the
1776 * dictionary, and set hash_head to the head of the hash chain:
1777 */
1778 if (s->lookahead >= MIN_MATCH) {
1779 INSERT_STRING(s, s->strstart, hash_head);
1780 }
1781
1782 /* Find the longest match, discarding those <= prev_length.
1783 * At this point we have always match_length < MIN_MATCH
1784 */
1785 if (hash_head != NIL && s->strstart - hash_head <= MAX_DIST(s)) {
1786 /* To simplify the code, we prevent matches with the string
1787 * of window index 0 (in particular we have to avoid a match
1788 * of the string with itself at the start of the input file).
1789 */
1790 if (s->strategy != Z_HUFFMAN_ONLY) {
1791 s->match_length = longest_match (s, hash_head);
1792 }
1793 /* longest_match() sets match_start */
1794 }
1795 if (s->match_length >= MIN_MATCH) {
1796 check_match(s, s->strstart, s->match_start, s->match_length);
1797
1798 _tr_tally_dist(s, s->strstart - s->match_start,
1799 s->match_length - MIN_MATCH, bflush);
1800
1801 s->lookahead -= s->match_length;
1802
1803 /* Insert new strings in the hash table only if the match length
1804 * is not too large. This saves time but degrades compression.
1805 */
1806 #ifndef FASTEST
1807 if (s->match_length <= s->max_insert_length &&
1808 s->lookahead >= MIN_MATCH) {
1809 s->match_length--; /* string at strstart already in hash table */
1810 do {
1811 s->strstart++;
1812 INSERT_STRING(s, s->strstart, hash_head);
1813 /* strstart never exceeds WSIZE-MAX_MATCH, so there are
1814 * always MIN_MATCH bytes ahead.
1815 */
1816 } while (--s->match_length != 0);
1817 s->strstart++;
1818 } else
1819 #endif
1820 {
1821 s->strstart += s->match_length;
1822 s->match_length = 0;
1823 s->ins_h = s->window[s->strstart];
1824 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
1825 #if MIN_MATCH != 3
1826 Call UPDATE_HASH() MIN_MATCH-3 more times
1827 #endif
1828 /* If lookahead < MIN_MATCH, ins_h is garbage, but it does not
1829 * matter since it will be recomputed at next deflate call.
1830 */
1831 }
1832 } else {
1833 /* No match, output a literal byte */
1834 Tracevv((stderr,"%c", s->window[s->strstart]));
1835 _tr_tally_lit (s, s->window[s->strstart], bflush);
1836 s->lookahead--;
1837 s->strstart++;
1838 }
1839 if (bflush) FLUSH_BLOCK(s, 0);
1840 }
1841 FLUSH_BLOCK(s, flush == Z_FINISH);
1842 return flush == Z_FINISH ? finish_done : block_done;
1843 }
1844
1845 /* ===========================================================================
1846 * Same as above, but achieves better compression. We use a lazy
1847 * evaluation for matches: a match is finally adopted only if there is
1848 * no better match at the next window position.
1849 */
1850 local block_state deflate_slow(s, flush)
1851 deflate_state *s;
1852 int flush;
1853 {
1854 IPos hash_head = NIL; /* head of hash chain */
1855 int bflush; /* set if current block must be flushed */
1856
1857 /* Process the input block. */
1858 for (;;) {
1859 /* Make sure that we always have enough lookahead, except
1860 * at the end of the input file. We need MAX_MATCH bytes
1861 * for the next match, plus MIN_MATCH bytes to insert the
1862 * string following the next match.
1863 */
1864 if (s->lookahead < MIN_LOOKAHEAD) {
1865 fill_window(s);
1866 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
1867 return need_more;
1868 }
1869 if (s->lookahead == 0) break; /* flush the current block */
1870 }
1871
1872 /* Insert the string window[strstart .. strstart+2] in the
1873 * dictionary, and set hash_head to the head of the hash chain:
1874 */
1875 if (s->lookahead >= MIN_MATCH) {
1876 INSERT_STRING(s, s->strstart, hash_head);
1877 }
1878
1879 /* Find the longest match, discarding those <= prev_length.
1880 */
1881 s->prev_length = s->match_length, s->prev_match = s->match_start;
1882 s->match_length = MIN_MATCH-1;
1883
1884 if (hash_head != NIL && s->prev_length < s->max_lazy_match &&
1885 s->strstart - hash_head <= MAX_DIST(s)) {
1886 /* To simplify the code, we prevent matches with the string
1887 * of window index 0 (in particular we have to avoid a match
1888 * of the string with itself at the start of the input file).
1889 */
1890 if (s->strategy != Z_HUFFMAN_ONLY) {
1891 s->match_length = longest_match (s, hash_head);
1892 }
1893 /* longest_match() sets match_start */
1894
1895 if (s->match_length <= 5 && (s->strategy == Z_FILTERED ||
1896 (s->match_length == MIN_MATCH &&
1897 s->strstart - s->match_start > TOO_FAR))) {
1898
1899 /* If prev_match is also MIN_MATCH, match_start is garbage
1900 * but we will ignore the current match anyway.
1901 */
1902 s->match_length = MIN_MATCH-1;
1903 }
1904 }
1905 /* If there was a match at the previous step and the current
1906 * match is not better, output the previous match:
1907 */
1908 if (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) {
1909 uInt max_insert = s->strstart + s->lookahead - MIN_MATCH;
1910 /* Do not insert strings in hash table beyond this. */
1911
1912 check_match(s, s->strstart-1, s->prev_match, s->prev_length);
1913
1914 _tr_tally_dist(s, s->strstart -1 - s->prev_match,
1915 s->prev_length - MIN_MATCH, bflush);
1916
1917 /* Insert in hash table all strings up to the end of the match.
1918 * strstart-1 and strstart are already inserted. If there is not
1919 * enough lookahead, the last two strings are not inserted in
1920 * the hash table.
1921 */
1922 s->lookahead -= s->prev_length-1;
1923 s->prev_length -= 2;
1924 do {
1925 if (++s->strstart <= max_insert) {
1926 INSERT_STRING(s, s->strstart, hash_head);
1927 }
1928 } while (--s->prev_length != 0);
1929 s->match_available = 0;
1930 s->match_length = MIN_MATCH-1;
1931 s->strstart++;
1932
1933 if (bflush) FLUSH_BLOCK(s, 0);
1934
1935 } else if (s->match_available) {
1936 /* If there was no match at the previous position, output a
1937 * single literal. If there was a match but the current match
1938 * is longer, truncate the previous match to a single literal.
1939 */
1940 Tracevv((stderr,"%c", s->window[s->strstart-1]));
1941 _tr_tally_lit(s, s->window[s->strstart-1], bflush);
1942 if (bflush) {
1943 FLUSH_BLOCK_ONLY(s, 0);
1944 }
1945 s->strstart++;
1946 s->lookahead--;
1947 if (s->strm->avail_out == 0) return need_more;
1948 } else {
1949 /* There is no previous match to compare with, wait for
1950 * the next step to decide.
1951 */
1952 s->match_available = 1;
1953 s->strstart++;
1954 s->lookahead--;
1955 }
1956 }
1957 Assert (flush != Z_NO_FLUSH, "no flush?");
1958 if (s->match_available) {
1959 Tracevv((stderr,"%c", s->window[s->strstart-1]));
1960 _tr_tally_lit(s, s->window[s->strstart-1], bflush);
1961 s->match_available = 0;
1962 }
1963 FLUSH_BLOCK(s, flush == Z_FINISH);
1964 return flush == Z_FINISH ? finish_done : block_done;
1965 }
1966 /* --- deflate.c */
1967
1968 /* +++ trees.c */
1969 /* trees.c -- output deflated data using Huffman coding
1970 * Copyright (C) 1995-2002 Jean-loup Gailly
1971 * For conditions of distribution and use, see copyright notice in zlib.h
1972 */
1973
1974 /*
1975 * ALGORITHM
1976 *
1977 * The "deflation" process uses several Huffman trees. The more
1978 * common source values are represented by shorter bit sequences.
1979 *
1980 * Each code tree is stored in a compressed form which is itself
1981 * a Huffman encoding of the lengths of all the code strings (in
1982 * ascending order by source values). The actual code strings are
1983 * reconstructed from the lengths in the inflate process, as described
1984 * in the deflate specification.
1985 *
1986 * REFERENCES
1987 *
1988 * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification".
1989 * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc
1990 *
1991 * Storer, James A.
1992 * Data Compression: Methods and Theory, pp. 49-50.
1993 * Computer Science Press, 1988. ISBN 0-7167-8156-5.
1994 *
1995 * Sedgewick, R.
1996 * Algorithms, p290.
1997 * Addison-Wesley, 1983. ISBN 0-201-06672-6.
1998 */
1999
2000 /* @(#) $Id: zlib.c,v 1.10 2004/07/29 19:17:20 lindak Exp $ */
2001
2002 /* #define GEN_TREES_H */
2003
2004 /* #include "deflate.h" */
2005
2006 #ifdef DEBUG_ZLIB
2007 # include <ctype.h>
2008 #endif
2009
2010 /* ===========================================================================
2011 * Constants
2012 */
2013
2014 #define MAX_BL_BITS 7
2015 /* Bit length codes must not exceed MAX_BL_BITS bits */
2016
2017 #define END_BLOCK 256
2018 /* end of block literal code */
2019
2020 #define REP_3_6 16
2021 /* repeat previous bit length 3-6 times (2 bits of repeat count) */
2022
2023 #define REPZ_3_10 17
2024 /* repeat a zero length 3-10 times (3 bits of repeat count) */
2025
2026 #define REPZ_11_138 18
2027 /* repeat a zero length 11-138 times (7 bits of repeat count) */
2028
2029 local const int extra_lbits[LENGTH_CODES] /* extra bits for each length code */
2030 = {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};
2031
2032 local const int extra_dbits[D_CODES] /* extra bits for each distance code */
2033 = {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};
2034
2035 local const int extra_blbits[BL_CODES]/* extra bits for each bit length code */
2036 = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7};
2037
2038 local const uch bl_order[BL_CODES]
2039 = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15};
2040 /* The lengths of the bit length codes are sent in order of decreasing
2041 * probability, to avoid transmitting the lengths for unused bit length codes.
2042 */
2043
2044 #define Buf_size (8 * 2*sizeof(char))
2045 /* Number of bits used within bi_buf. (bi_buf might be implemented on
2046 * more than 16 bits on some systems.)
2047 */
2048
2049 /* ===========================================================================
2050 * Local data. These are initialized only once.
2051 */
2052
2053 #define DIST_CODE_LEN 512 /* see definition of array dist_code below */
2054
2055 #if defined(GEN_TREES_H) || !defined(STDC)
2056 /* non ANSI compilers may not accept trees.h */
2057
2058 local ct_data *static_ltree = Z_NULL;
2059 /* The static literal tree. Since the bit lengths are imposed, there is no
2060 * need for the L_CODES extra codes used during heap construction. However
2061 * The codes 286 and 287 are needed to build a canonical tree (see _tr_init
2062 * below).
2063 */
2064
2065 local ct_data *static_dtree = Z_NULL;
2066 /* The static distance tree. (Actually a trivial tree since all codes use
2067 * 5 bits.)
2068 */
2069
2070 uch *_dist_code = Z_NULL;
2071 /* Distance codes. The first 256 values correspond to the distances
2072 * 3 .. 258, the last 256 values correspond to the top 8 bits of
2073 * the 15 bit distances.
2074 */
2075
2076 uch *_length_code = Z_NULL;
2077 /* length code for each normalized match length (0 == MIN_MATCH) */
2078
2079 local int *base_length = Z_NULL;
2080 /* First normalized length for each code (0 = MIN_MATCH) */
2081
2082 local int *base_dist = Z_NULL;
2083 /* First normalized distance for each code (0 = distance of 1) */
2084
2085 #else
2086 /* +++ trees.h */
2087 /* header created automatically with -DGEN_TREES_H */
2088
2089 local const ct_data static_ltree[L_CODES+2] = {
2090 {{ 12},{ 8}}, {{140},{ 8}}, {{ 76},{ 8}}, {{204},{ 8}}, {{ 44},{ 8}},
2091 {{172},{ 8}}, {{108},{ 8}}, {{236},{ 8}}, {{ 28},{ 8}}, {{156},{ 8}},
2092 {{ 92},{ 8}}, {{220},{ 8}}, {{ 60},{ 8}}, {{188},{ 8}}, {{124},{ 8}},
2093 {{252},{ 8}}, {{ 2},{ 8}}, {{130},{ 8}}, {{ 66},{ 8}}, {{194},{ 8}},
2094 {{ 34},{ 8}}, {{162},{ 8}}, {{ 98},{ 8}}, {{226},{ 8}}, {{ 18},{ 8}},
2095 {{146},{ 8}}, {{ 82},{ 8}}, {{210},{ 8}}, {{ 50},{ 8}}, {{178},{ 8}},
2096 {{114},{ 8}}, {{242},{ 8}}, {{ 10},{ 8}}, {{138},{ 8}}, {{ 74},{ 8}},
2097 {{202},{ 8}}, {{ 42},{ 8}}, {{170},{ 8}}, {{106},{ 8}}, {{234},{ 8}},
2098 {{ 26},{ 8}}, {{154},{ 8}}, {{ 90},{ 8}}, {{218},{ 8}}, {{ 58},{ 8}},
2099 {{186},{ 8}}, {{122},{ 8}}, {{250},{ 8}}, {{ 6},{ 8}}, {{134},{ 8}},
2100 {{ 70},{ 8}}, {{198},{ 8}}, {{ 38},{ 8}}, {{166},{ 8}}, {{102},{ 8}},
2101 {{230},{ 8}}, {{ 22},{ 8}}, {{150},{ 8}}, {{ 86},{ 8}}, {{214},{ 8}},
2102 {{ 54},{ 8}}, {{182},{ 8}}, {{118},{ 8}}, {{246},{ 8}}, {{ 14},{ 8}},
2103 {{142},{ 8}}, {{ 78},{ 8}}, {{206},{ 8}}, {{ 46},{ 8}}, {{174},{ 8}},
2104 {{110},{ 8}}, {{238},{ 8}}, {{ 30},{ 8}}, {{158},{ 8}}, {{ 94},{ 8}},
2105 {{222},{ 8}}, {{ 62},{ 8}}, {{190},{ 8}}, {{126},{ 8}}, {{254},{ 8}},
2106 {{ 1},{ 8}}, {{129},{ 8}}, {{ 65},{ 8}}, {{193},{ 8}}, {{ 33},{ 8}},
2107 {{161},{ 8}}, {{ 97},{ 8}}, {{225},{ 8}}, {{ 17},{ 8}}, {{145},{ 8}},
2108 {{ 81},{ 8}}, {{209},{ 8}}, {{ 49},{ 8}}, {{177},{ 8}}, {{113},{ 8}},
2109 {{241},{ 8}}, {{ 9},{ 8}}, {{137},{ 8}}, {{ 73},{ 8}}, {{201},{ 8}},
2110 {{ 41},{ 8}}, {{169},{ 8}}, {{105},{ 8}}, {{233},{ 8}}, {{ 25},{ 8}},
2111 {{153},{ 8}}, {{ 89},{ 8}}, {{217},{ 8}}, {{ 57},{ 8}}, {{185},{ 8}},
2112 {{121},{ 8}}, {{249},{ 8}}, {{ 5},{ 8}}, {{133},{ 8}}, {{ 69},{ 8}},
2113 {{197},{ 8}}, {{ 37},{ 8}}, {{165},{ 8}}, {{101},{ 8}}, {{229},{ 8}},
2114 {{ 21},{ 8}}, {{149},{ 8}}, {{ 85},{ 8}}, {{213},{ 8}}, {{ 53},{ 8}},
2115 {{181},{ 8}}, {{117},{ 8}}, {{245},{ 8}}, {{ 13},{ 8}}, {{141},{ 8}},
2116 {{ 77},{ 8}}, {{205},{ 8}}, {{ 45},{ 8}}, {{173},{ 8}}, {{109},{ 8}},
2117 {{237},{ 8}}, {{ 29},{ 8}}, {{157},{ 8}}, {{ 93},{ 8}}, {{221},{ 8}},
2118 {{ 61},{ 8}}, {{189},{ 8}}, {{125},{ 8}}, {{253},{ 8}}, {{ 19},{ 9}},
2119 {{275},{ 9}}, {{147},{ 9}}, {{403},{ 9}}, {{ 83},{ 9}}, {{339},{ 9}},
2120 {{211},{ 9}}, {{467},{ 9}}, {{ 51},{ 9}}, {{307},{ 9}}, {{179},{ 9}},
2121 {{435},{ 9}}, {{115},{ 9}}, {{371},{ 9}}, {{243},{ 9}}, {{499},{ 9}},
2122 {{ 11},{ 9}}, {{267},{ 9}}, {{139},{ 9}}, {{395},{ 9}}, {{ 75},{ 9}},
2123 {{331},{ 9}}, {{203},{ 9}}, {{459},{ 9}}, {{ 43},{ 9}}, {{299},{ 9}},
2124 {{171},{ 9}}, {{427},{ 9}}, {{107},{ 9}}, {{363},{ 9}}, {{235},{ 9}},
2125 {{491},{ 9}}, {{ 27},{ 9}}, {{283},{ 9}}, {{155},{ 9}}, {{411},{ 9}},
2126 {{ 91},{ 9}}, {{347},{ 9}}, {{219},{ 9}}, {{475},{ 9}}, {{ 59},{ 9}},
2127 {{315},{ 9}}, {{187},{ 9}}, {{443},{ 9}}, {{123},{ 9}}, {{379},{ 9}},
2128 {{251},{ 9}}, {{507},{ 9}}, {{ 7},{ 9}}, {{263},{ 9}}, {{135},{ 9}},
2129 {{391},{ 9}}, {{ 71},{ 9}}, {{327},{ 9}}, {{199},{ 9}}, {{455},{ 9}},
2130 {{ 39},{ 9}}, {{295},{ 9}}, {{167},{ 9}}, {{423},{ 9}}, {{103},{ 9}},
2131 {{359},{ 9}}, {{231},{ 9}}, {{487},{ 9}}, {{ 23},{ 9}}, {{279},{ 9}},
2132 {{151},{ 9}}, {{407},{ 9}}, {{ 87},{ 9}}, {{343},{ 9}}, {{215},{ 9}},
2133 {{471},{ 9}}, {{ 55},{ 9}}, {{311},{ 9}}, {{183},{ 9}}, {{439},{ 9}},
2134 {{119},{ 9}}, {{375},{ 9}}, {{247},{ 9}}, {{503},{ 9}}, {{ 15},{ 9}},
2135 {{271},{ 9}}, {{143},{ 9}}, {{399},{ 9}}, {{ 79},{ 9}}, {{335},{ 9}},
2136 {{207},{ 9}}, {{463},{ 9}}, {{ 47},{ 9}}, {{303},{ 9}}, {{175},{ 9}},
2137 {{431},{ 9}}, {{111},{ 9}}, {{367},{ 9}}, {{239},{ 9}}, {{495},{ 9}},
2138 {{ 31},{ 9}}, {{287},{ 9}}, {{159},{ 9}}, {{415},{ 9}}, {{ 95},{ 9}},
2139 {{351},{ 9}}, {{223},{ 9}}, {{479},{ 9}}, {{ 63},{ 9}}, {{319},{ 9}},
2140 {{191},{ 9}}, {{447},{ 9}}, {{127},{ 9}}, {{383},{ 9}}, {{255},{ 9}},
2141 {{511},{ 9}}, {{ 0},{ 7}}, {{ 64},{ 7}}, {{ 32},{ 7}}, {{ 96},{ 7}},
2142 {{ 16},{ 7}}, {{ 80},{ 7}}, {{ 48},{ 7}}, {{112},{ 7}}, {{ 8},{ 7}},
2143 {{ 72},{ 7}}, {{ 40},{ 7}}, {{104},{ 7}}, {{ 24},{ 7}}, {{ 88},{ 7}},
2144 {{ 56},{ 7}}, {{120},{ 7}}, {{ 4},{ 7}}, {{ 68},{ 7}}, {{ 36},{ 7}},
2145 {{100},{ 7}}, {{ 20},{ 7}}, {{ 84},{ 7}}, {{ 52},{ 7}}, {{116},{ 7}},
2146 {{ 3},{ 8}}, {{131},{ 8}}, {{ 67},{ 8}}, {{195},{ 8}}, {{ 35},{ 8}},
2147 {{163},{ 8}}, {{ 99},{ 8}}, {{227},{ 8}}
2148 };
2149
2150 local const ct_data static_dtree[D_CODES] = {
2151 {{ 0},{ 5}}, {{16},{ 5}}, {{ 8},{ 5}}, {{24},{ 5}}, {{ 4},{ 5}},
2152 {{20},{ 5}}, {{12},{ 5}}, {{28},{ 5}}, {{ 2},{ 5}}, {{18},{ 5}},
2153 {{10},{ 5}}, {{26},{ 5}}, {{ 6},{ 5}}, {{22},{ 5}}, {{14},{ 5}},
2154 {{30},{ 5}}, {{ 1},{ 5}}, {{17},{ 5}}, {{ 9},{ 5}}, {{25},{ 5}},
2155 {{ 5},{ 5}}, {{21},{ 5}}, {{13},{ 5}}, {{29},{ 5}}, {{ 3},{ 5}},
2156 {{19},{ 5}}, {{11},{ 5}}, {{27},{ 5}}, {{ 7},{ 5}}, {{23},{ 5}}
2157 };
2158
2159 const uch _dist_code[DIST_CODE_LEN] = {
2160 0, 1, 2, 3, 4, 4, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8, 8,
2161 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 10,
2162 10, 10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11,
2163 11, 11, 11, 11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
2164 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 13, 13, 13, 13,
2165 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13,
2166 13, 13, 13, 13, 13, 13, 13, 13, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
2167 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
2168 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
2169 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 15, 15, 15, 15, 15, 15, 15, 15,
2170 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
2171 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
2172 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 0, 0, 16, 17,
2173 18, 18, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 22, 22, 22, 22, 22, 22, 22, 22,
2174 23, 23, 23, 23, 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
2175 24, 24, 24, 24, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
2176 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
2177 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 27, 27, 27, 27, 27, 27, 27, 27,
2178 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
2179 27, 27, 27, 27, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
2180 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
2181 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
2182 28, 28, 28, 28, 28, 28, 28, 28, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
2183 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
2184 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
2185 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29
2186 };
2187
2188 const uch _length_code[MAX_MATCH-MIN_MATCH+1]= {
2189 0, 1, 2, 3, 4, 5, 6, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 12, 12,
2190 13, 13, 13, 13, 14, 14, 14, 14, 15, 15, 15, 15, 16, 16, 16, 16, 16, 16, 16, 16,
2191 17, 17, 17, 17, 17, 17, 17, 17, 18, 18, 18, 18, 18, 18, 18, 18, 19, 19, 19, 19,
2192 19, 19, 19, 19, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20,
2193 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 22, 22, 22, 22,
2194 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 23, 23, 23, 23, 23, 23, 23, 23,
2195 23, 23, 23, 23, 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
2196 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
2197 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
2198 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 26, 26, 26, 26, 26, 26, 26, 26,
2199 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
2200 26, 26, 26, 26, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
2201 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 28
2202 };
2203
2204 local const int base_length[LENGTH_CODES] = {
2205 0, 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, 16, 20, 24, 28, 32, 40, 48, 56,
2206 64, 80, 96, 112, 128, 160, 192, 224, 0
2207 };
2208
2209 local const int base_dist[D_CODES] = {
2210 0, 1, 2, 3, 4, 6, 8, 12, 16, 24,
2211 32, 48, 64, 96, 128, 192, 256, 384, 512, 768,
2212 1024, 1536, 2048, 3072, 4096, 6144, 8192, 12288, 16384, 24576
2213 };
2214
2215 /* --- trees.h */
2216 #endif /* GEN_TREES_H */
2217
2218 struct static_tree_desc_s {
2219 const ct_data *static_tree; /* static tree or NULL */
2220 const intf *extra_bits; /* extra bits for each code or NULL */
2221 int extra_base; /* base index for extra_bits */
2222 int elems; /* max number of elements in the tree */
2223 int max_length; /* max bit length for the codes */
2224 };
2225
2226 local static_tree_desc static_l_desc =
2227 {NULL, extra_lbits, LITERALS+1, L_CODES, MAX_BITS};
2228
2229 local static_tree_desc static_d_desc =
2230 {NULL, extra_dbits, 0, D_CODES, MAX_BITS};
2231
2232 local static_tree_desc static_bl_desc =
2233 {(const ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS};
2234
2235 /* ===========================================================================
2236 * Local (static) routines in this file.
2237 */
2238
2239 local int tr_static_init OF((z_streamp z));
2240 local void init_block OF((deflate_state *s));
2241 local void pqdownheap OF((deflate_state *s, ct_data *tree, int k));
2242 local void gen_bitlen OF((deflate_state *s, tree_desc *desc));
2243 local void gen_codes OF((ct_data *tree, int max_code, ushf *bl_count));
2244 local void build_tree OF((deflate_state *s, tree_desc *desc));
2245 local void scan_tree OF((deflate_state *s, ct_data *tree, int max_code));
2246 local void send_tree OF((deflate_state *s, ct_data *tree, int max_code));
2247 local int build_bl_tree OF((deflate_state *s));
2248 local void send_all_trees OF((deflate_state *s, int lcodes, int dcodes,
2249 int blcodes));
2250 local void compress_block OF((deflate_state *s, ct_data *ltree,
2251 ct_data *dtree));
2252 local void set_data_type OF((deflate_state *s));
2253 local unsigned bi_reverse OF((unsigned value, int length));
2254 local void bi_windup OF((deflate_state *s));
2255 local void bi_flush OF((deflate_state *s));
2256 local void copy_block OF((deflate_state *s, charf *buf, unsigned len,
2257 int header));
2258
2259 #ifdef GEN_TREES_H
2260 local void gen_trees_header OF((void));
2261 #endif
2262
2263 #ifndef DEBUG_ZLIB
2264 # define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len)
2265 /* Send a code of the given tree. c and tree must not have side effects */
2266
2267 #else /* DEBUG_ZLIB */
2268 # define send_code(s, c, tree) \
2269 { if (z_verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \
2270 send_bits(s, tree[c].Code, tree[c].Len); }
2271 #endif
2272
2273 /* ===========================================================================
2274 * Output a short LSB first on the stream.
2275 * IN assertion: there is enough room in pendingBuf.
2276 */
2277 #define put_short(s, w) { \
2278 put_byte(s, (uch)((w) & 0xff)); \
2279 put_byte(s, (uch)((ush)(w) >> 8)); \
2280 }
2281
2282 /* ===========================================================================
2283 * Send a value on a given number of bits.
2284 * IN assertion: length <= 16 and value fits in length bits.
2285 */
2286 #ifdef DEBUG_ZLIB
2287 local void send_bits OF((deflate_state *s, int value, int length));
2288
2289 local void send_bits(s, value, length)
2290 deflate_state *s;
2291 int value; /* value to send */
2292 int length; /* number of bits */
2293 {
2294 Tracevv((stderr," l %2d v %4x ", length, value));
2295 Assert(length > 0 && length <= 15, "invalid length");
2296 s->bits_sent += (ulg)length;
2297
2298 /* If not enough room in bi_buf, use (valid) bits from bi_buf and
2299 * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid))
2300 * unused bits in value.
2301 */
2302 if (s->bi_valid > (int)Buf_size - length) {
2303 s->bi_buf |= (value << s->bi_valid);
2304 put_short(s, s->bi_buf);
2305 s->bi_buf = (ush)value >> (Buf_size - s->bi_valid);
2306 s->bi_valid += length - Buf_size;
2307 } else {
2308 s->bi_buf |= value << s->bi_valid;
2309 s->bi_valid += length;
2310 }
2311 }
2312 #else /* !DEBUG_ZLIB */
2313
2314 #define send_bits(s, value, length) \
2315 { int len = length;\
2316 if (s->bi_valid > (int)Buf_size - len) {\
2317 int val = value;\
2318 s->bi_buf |= (val << s->bi_valid);\
2319 put_short(s, s->bi_buf);\
2320 s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\
2321 s->bi_valid += len - Buf_size;\
2322 } else {\
2323 s->bi_buf |= (value) << s->bi_valid;\
2324 s->bi_valid += len;\
2325 }\
2326 }
2327 #endif /* DEBUG_ZLIB */
2328
2329
2330 #ifndef MAX
2331 #define MAX(a,b) (a >= b ? a : b)
2332 #endif
2333 /* the arguments must not have side effects */
2334
2335 typedef struct {
2336 ct_data static_ltree[L_CODES+2];
2337 ct_data static_dtree[D_CODES];
2338 uch _dist_code[DIST_CODE_LEN];
2339 uch _length_code[MAX_MATCH-MIN_MATCH+1];
2340 int base_length[LENGTH_CODES];
2341 int base_dist[D_CODES];
2342 } __used_to_be_static;
2343
2344 static __used_to_be_static *static_storage = Z_NULL;
2345
2346 /* ===========================================================================
2347 * Initialize the various 'constant' tables.
2348 */
2349 local int tr_static_init(
2350 z_streamp z)
2351 {
2352 #if defined(GEN_TREES_H) || !defined(STDC)
2353 static int static_init_done = 0;
2354 int n; /* iterates over tree elements */
2355 int bits; /* bit counter */
2356 int length; /* length value */
2357 int code; /* code value */
2358 int dist; /* distance index */
2359 ush bl_count[MAX_BITS+1];
2360 /* number of codes at each bit length for an optimal tree */
2361
2362 if (static_init_done) return Z_OK;
2363
2364 /* allocate storage for static structures */
2365 if (static_storage == Z_NULL) {
2366 static_storage = (__used_to_be_static*)ZALLOC(z, 1, sizeof(__used_to_be_static));
2367 if (static_storage == Z_NULL)
2368 return Z_MEM_ERROR;
2369 }
2370
2371 static_ltree = static_storage->static_ltree;
2372 static_dtree = static_storage->static_dtree;
2373 _dist_code = static_storage->_dist_code;
2374 _length_code = static_storage->_length_code;
2375 base_length = static_storage->base_length;
2376 base_dist = static_storage->base_dist;
2377
2378 /* For some embedded targets, global variables are not initialized: */
2379 static_l_desc.static_tree = static_ltree;
2380 static_l_desc.extra_bits = extra_lbits;
2381 static_d_desc.static_tree = static_dtree;
2382 static_d_desc.extra_bits = extra_dbits;
2383 static_bl_desc.extra_bits = extra_blbits;
2384
2385 /* Initialize the mapping length (0..255) -> length code (0..28) */
2386 length = 0;
2387 for (code = 0; code < LENGTH_CODES-1; code++) {
2388 base_length[code] = length;
2389 for (n = 0; n < (1<<extra_lbits[code]); n++) {
2390 _length_code[length++] = (uch)code;
2391 }
2392 }
2393 Assert (length == 256, "tr_static_init: length != 256");
2394 /* Note that the length 255 (match length 258) can be represented
2395 * in two different ways: code 284 + 5 bits or code 285, so we
2396 * overwrite length_code[255] to use the best encoding:
2397 */
2398 _length_code[length-1] = (uch)code;
2399
2400 /* Initialize the mapping dist (0..32K) -> dist code (0..29) */
2401 dist = 0;
2402 for (code = 0 ; code < 16; code++) {
2403 base_dist[code] = dist;
2404 for (n = 0; n < (1<<extra_dbits[code]); n++) {
2405 _dist_code[dist++] = (uch)code;
2406 }
2407 }
2408 Assert (dist == 256, "tr_static_init: dist != 256");
2409 dist >>= 7; /* from now on, all distances are divided by 128 */
2410 for ( ; code < D_CODES; code++) {
2411 base_dist[code] = dist << 7;
2412 for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) {
2413 _dist_code[256 + dist++] = (uch)code;
2414 }
2415 }
2416 Assert (dist == 256, "tr_static_init: 256+dist != 512");
2417
2418 /* Construct the codes of the static literal tree */
2419 for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
2420 n = 0;
2421 while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++;
2422 while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++;
2423 while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++;
2424 while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++;
2425 /* Codes 286 and 287 do not exist, but we must include them in the
2426 * tree construction to get a canonical Huffman tree (longest code
2427 * all ones)
2428 */
2429 gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count);
2430
2431 /* The static distance tree is trivial: */
2432 for (n = 0; n < D_CODES; n++) {
2433 static_dtree[n].Len = 5;
2434 static_dtree[n].Code = bi_reverse((unsigned)n, 5);
2435 }
2436 static_init_done = 1;
2437
2438 # ifdef GEN_TREES_H
2439 gen_trees_header();
2440 # endif
2441 #endif /* defined(GEN_TREES_H) || !defined(STDC) */
2442 return Z_OK;
2443 }
2444
2445 /* ===========================================================================
2446 * Genererate the file trees.h describing the static trees.
2447 */
2448 #ifdef GEN_TREES_H
2449 # ifndef DEBUG_ZLIB
2450 # include <stdio.h>
2451 # endif
2452
2453 # define SEPARATOR(i, last, width) \
2454 ((i) == (last)? "\n};\n\n" : \
2455 ((i) % (width) == (width)-1 ? ",\n" : ", "))
2456
2457 void gen_trees_header()
2458 {
2459 FILE *header = fopen("trees.h", "w");
2460 int i;
2461
2462 Assert (header != NULL, "Can't open trees.h");
2463 fprintf(header,
2464 "/* header created automatically with -DGEN_TREES_H */\n\n");
2465
2466 fprintf(header, "local const ct_data static_ltree[L_CODES+2] = {\n");
2467 for (i = 0; i < L_CODES+2; i++) {
2468 fprintf(header, "{{%3u},{%3u}}%s", static_ltree[i].Code,
2469 static_ltree[i].Len, SEPARATOR(i, L_CODES+1, 5));
2470 }
2471
2472 fprintf(header, "local const ct_data static_dtree[D_CODES] = {\n");
2473 for (i = 0; i < D_CODES; i++) {
2474 fprintf(header, "{{%2u},{%2u}}%s", static_dtree[i].Code,
2475 static_dtree[i].Len, SEPARATOR(i, D_CODES-1, 5));
2476 }
2477
2478 fprintf(header, "const uch _dist_code[DIST_CODE_LEN] = {\n");
2479 for (i = 0; i < DIST_CODE_LEN; i++) {
2480 fprintf(header, "%2u%s", _dist_code[i],
2481 SEPARATOR(i, DIST_CODE_LEN-1, 20));
2482 }
2483
2484 fprintf(header, "const uch _length_code[MAX_MATCH-MIN_MATCH+1]= {\n");
2485 for (i = 0; i < MAX_MATCH-MIN_MATCH+1; i++) {
2486 fprintf(header, "%2u%s", _length_code[i],
2487 SEPARATOR(i, MAX_MATCH-MIN_MATCH, 20));
2488 }
2489
2490 fprintf(header, "local const int base_length[LENGTH_CODES] = {\n");
2491 for (i = 0; i < LENGTH_CODES; i++) {
2492 fprintf(header, "%1u%s", base_length[i],
2493 SEPARATOR(i, LENGTH_CODES-1, 20));
2494 }
2495
2496 fprintf(header, "local const int base_dist[D_CODES] = {\n");
2497 for (i = 0; i < D_CODES; i++) {
2498 fprintf(header, "%5u%s", base_dist[i],
2499 SEPARATOR(i, D_CODES-1, 10));
2500 }
2501
2502 fclose(header);
2503 }
2504 #endif /* GEN_TREES_H */
2505
2506 /* ===========================================================================
2507 * Initialize the tree data structures for a new zlib stream.
2508 */
2509 void _tr_init(s)
2510 deflate_state *s;
2511 {
2512 tr_static_init(s->strm);
2513
2514 s->l_desc.dyn_tree = s->dyn_ltree;
2515 s->l_desc.stat_desc = &static_l_desc;
2516
2517 s->d_desc.dyn_tree = s->dyn_dtree;
2518 s->d_desc.stat_desc = &static_d_desc;
2519
2520 s->bl_desc.dyn_tree = s->bl_tree;
2521 s->bl_desc.stat_desc = &static_bl_desc;
2522
2523 s->bi_buf = 0;
2524 s->bi_valid = 0;
2525 s->last_eob_len = 8; /* enough lookahead for inflate */
2526 #ifdef DEBUG_ZLIB
2527 s->compressed_len = 0L;
2528 s->bits_sent = 0L;
2529 #endif
2530
2531 /* Initialize the first block of the first file: */
2532 init_block(s);
2533 }
2534
2535 /* ===========================================================================
2536 * Initialize a new block.
2537 */
2538 local void init_block(s)
2539 deflate_state *s;
2540 {
2541 int n; /* iterates over tree elements */
2542
2543 /* Initialize the trees. */
2544 for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0;
2545 for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0;
2546 for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0;
2547
2548 s->dyn_ltree[END_BLOCK].Freq = 1;
2549 s->opt_len = s->static_len = 0L;
2550 s->last_lit = s->matches = 0;
2551 }
2552
2553 #define SMALLEST 1
2554 /* Index within the heap array of least frequent node in the Huffman tree */
2555
2556
2557 /* ===========================================================================
2558 * Remove the smallest element from the heap and recreate the heap with
2559 * one less element. Updates heap and heap_len.
2560 */
2561 #define pqremove(s, tree, top) \
2562 {\
2563 top = s->heap[SMALLEST]; \
2564 s->heap[SMALLEST] = s->heap[s->heap_len--]; \
2565 pqdownheap(s, tree, SMALLEST); \
2566 }
2567
2568 /* ===========================================================================
2569 * Compares to subtrees, using the tree depth as tie breaker when
2570 * the subtrees have equal frequency. This minimizes the worst case length.
2571 */
2572 #define smaller(tree, n, m, depth) \
2573 (tree[n].Freq < tree[m].Freq || \
2574 (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m]))
2575
2576 /* ===========================================================================
2577 * Restore the heap property by moving down the tree starting at node k,
2578 * exchanging a node with the smallest of its two sons if necessary, stopping
2579 * when the heap property is re-established (each father smaller than its
2580 * two sons).
2581 */
2582 local void pqdownheap(s, tree, k)
2583 deflate_state *s;
2584 ct_data *tree; /* the tree to restore */
2585 int k; /* node to move down */
2586 {
2587 int v = s->heap[k];
2588 int j = k << 1; /* left son of k */
2589 while (j <= s->heap_len) {
2590 /* Set j to the smallest of the two sons: */
2591 if (j < s->heap_len &&
2592 smaller(tree, s->heap[j+1], s->heap[j], s->depth)) {
2593 j++;
2594 }
2595 /* Exit if v is smaller than both sons */
2596 if (smaller(tree, v, s->heap[j], s->depth)) break;
2597
2598 /* Exchange v with the smallest son */
2599 s->heap[k] = s->heap[j]; k = j;
2600
2601 /* And continue down the tree, setting j to the left son of k */
2602 j <<= 1;
2603 }
2604 s->heap[k] = v;
2605 }
2606
2607 /* ===========================================================================
2608 * Compute the optimal bit lengths for a tree and update the total bit length
2609 * for the current block.
2610 * IN assertion: the fields freq and dad are set, heap[heap_max] and
2611 * above are the tree nodes sorted by increasing frequency.
2612 * OUT assertions: the field len is set to the optimal bit length, the
2613 * array bl_count contains the frequencies for each bit length.
2614 * The length opt_len is updated; static_len is also updated if stree is
2615 * not null.
2616 */
2617 local void gen_bitlen(s, desc)
2618 deflate_state *s;
2619 tree_desc *desc; /* the tree descriptor */
2620 {
2621 ct_data *tree = desc->dyn_tree;
2622 int max_code = desc->max_code;
2623 const ct_data *stree = desc->stat_desc->static_tree;
2624 const intf *extra = desc->stat_desc->extra_bits;
2625 int base = desc->stat_desc->extra_base;
2626 int max_length = desc->stat_desc->max_length;
2627 int h; /* heap index */
2628 int n, m; /* iterate over the tree elements */
2629 int bits; /* bit length */
2630 int xbits; /* extra bits */
2631 ush f; /* frequency */
2632 int overflow = 0; /* number of elements with bit length too large */
2633
2634 for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0;
2635
2636 /* In a first pass, compute the optimal bit lengths (which may
2637 * overflow in the case of the bit length tree).
2638 */
2639 tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */
2640
2641 for (h = s->heap_max+1; h < HEAP_SIZE; h++) {
2642 n = s->heap[h];
2643 bits = tree[tree[n].Dad].Len + 1;
2644 if (bits > max_length) bits = max_length, overflow++;
2645 tree[n].Len = (ush)bits;
2646 /* We overwrite tree[n].Dad which is no longer needed */
2647
2648 if (n > max_code) continue; /* not a leaf node */
2649
2650 s->bl_count[bits]++;
2651 xbits = 0;
2652 if (n >= base) xbits = extra[n-base];
2653 f = tree[n].Freq;
2654 s->opt_len += (ulg)f * (bits + xbits);
2655 if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits);
2656 }
2657 if (overflow == 0) return;
2658
2659 Trace((stderr,"\nbit length overflow\n"));
2660 /* This happens for example on obj2 and pic of the Calgary corpus */
2661
2662 /* Find the first bit length which could increase: */
2663 do {
2664 bits = max_length-1;
2665 while (s->bl_count[bits] == 0) bits--;
2666 s->bl_count[bits]--; /* move one leaf down the tree */
2667 s->bl_count[bits+1] += 2; /* move one overflow item as its brother */
2668 s->bl_count[max_length]--;
2669 /* The brother of the overflow item also moves one step up,
2670 * but this does not affect bl_count[max_length]
2671 */
2672 overflow -= 2;
2673 } while (overflow > 0);
2674
2675 /* Now recompute all bit lengths, scanning in increasing frequency.
2676 * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
2677 * lengths instead of fixing only the wrong ones. This idea is taken
2678 * from 'ar' written by Haruhiko Okumura.)
2679 */
2680 for (bits = max_length; bits != 0; bits--) {
2681 n = s->bl_count[bits];
2682 while (n != 0) {
2683 m = s->heap[--h];
2684 if (m > max_code) continue;
2685 if (tree[m].Len != (unsigned) bits) {
2686 Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits));
2687 s->opt_len += ((long)bits - (long)tree[m].Len)
2688 *(long)tree[m].Freq;
2689 tree[m].Len = (ush)bits;
2690 }
2691 n--;
2692 }
2693 }
2694 }
2695
2696 /* ===========================================================================
2697 * Generate the codes for a given tree and bit counts (which need not be
2698 * optimal).
2699 * IN assertion: the array bl_count contains the bit length statistics for
2700 * the given tree and the field len is set for all tree elements.
2701 * OUT assertion: the field code is set for all tree elements of non
2702 * zero code length.
2703 */
2704 local void gen_codes (tree, max_code, bl_count)
2705 ct_data *tree; /* the tree to decorate */
2706 int max_code; /* largest code with non zero frequency */
2707 ushf *bl_count; /* number of codes at each bit length */
2708 {
2709 ush next_code[MAX_BITS+1]; /* next code value for each bit length */
2710 ush code = 0; /* running code value */
2711 int bits; /* bit index */
2712 int n; /* code index */
2713
2714 /* The distribution counts are first used to generate the code values
2715 * without bit reversal.
2716 */
2717 for (bits = 1; bits <= MAX_BITS; bits++) {
2718 next_code[bits] = code = (code + bl_count[bits-1]) << 1;
2719 }
2720 /* Check that the bit counts in bl_count are consistent. The last code
2721 * must be all ones.
2722 */
2723 Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1,
2724 "inconsistent bit counts");
2725 Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
2726
2727 for (n = 0; n <= max_code; n++) {
2728 int len = tree[n].Len;
2729 if (len == 0) continue;
2730 /* Now reverse the bits */
2731 tree[n].Code = bi_reverse(next_code[len]++, len);
2732
2733 Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
2734 n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1));
2735 }
2736 }
2737
2738 /* ===========================================================================
2739 * Construct one Huffman tree and assigns the code bit strings and lengths.
2740 * Update the total bit length for the current block.
2741 * IN assertion: the field freq is set for all tree elements.
2742 * OUT assertions: the fields len and code are set to the optimal bit length
2743 * and corresponding code. The length opt_len is updated; static_len is
2744 * also updated if stree is not null. The field max_code is set.
2745 */
2746 local void build_tree(s, desc)
2747 deflate_state *s;
2748 tree_desc *desc; /* the tree descriptor */
2749 {
2750 ct_data *tree = desc->dyn_tree;
2751 const ct_data *stree = desc->stat_desc->static_tree;
2752 int elems = desc->stat_desc->elems;
2753 int n, m; /* iterate over heap elements */
2754 int max_code = -1; /* largest code with non zero frequency */
2755 int node; /* new node being created */
2756
2757 /* Construct the initial heap, with least frequent element in
2758 * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
2759 * heap[0] is not used.
2760 */
2761 s->heap_len = 0, s->heap_max = HEAP_SIZE;
2762
2763 for (n = 0; n < elems; n++) {
2764 if (tree[n].Freq != 0) {
2765 s->heap[++(s->heap_len)] = max_code = n;
2766 s->depth[n] = 0;
2767 } else {
2768 tree[n].Len = 0;
2769 }
2770 }
2771
2772 /* The pkzip format requires that at least one distance code exists,
2773 * and that at least one bit should be sent even if there is only one
2774 * possible code. So to avoid special checks later on we force at least
2775 * two codes of non zero frequency.
2776 */
2777 while (s->heap_len < 2) {
2778 node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0);
2779 tree[node].Freq = 1;
2780 s->depth[node] = 0;
2781 s->opt_len--; if (stree) s->static_len -= stree[node].Len;
2782 /* node is 0 or 1 so it does not have extra bits */
2783 }
2784 desc->max_code = max_code;
2785
2786 /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
2787 * establish sub-heaps of increasing lengths:
2788 */
2789 for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n);
2790
2791 /* Construct the Huffman tree by repeatedly combining the least two
2792 * frequent nodes.
2793 */
2794 node = elems; /* next internal node of the tree */
2795 do {
2796 pqremove(s, tree, n); /* n = node of least frequency */
2797 m = s->heap[SMALLEST]; /* m = node of next least frequency */
2798
2799 s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */
2800 s->heap[--(s->heap_max)] = m;
2801
2802 /* Create a new node father of n and m */
2803 tree[node].Freq = tree[n].Freq + tree[m].Freq;
2804 s->depth[node] = (uch) (MAX(s->depth[n], s->depth[m]) + 1);
2805 tree[n].Dad = tree[m].Dad = (ush)node;
2806 #ifdef DUMP_BL_TREE
2807 if (tree == s->bl_tree) {
2808 fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)",
2809 node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq);
2810 }
2811 #endif
2812 /* and insert the new node in the heap */
2813 s->heap[SMALLEST] = node++;
2814 pqdownheap(s, tree, SMALLEST);
2815
2816 } while (s->heap_len >= 2);
2817
2818 s->heap[--(s->heap_max)] = s->heap[SMALLEST];
2819
2820 /* At this point, the fields freq and dad are set. We can now
2821 * generate the bit lengths.
2822 */
2823 gen_bitlen(s, (tree_desc *)desc);
2824
2825 /* The field len is now set, we can generate the bit codes */
2826 gen_codes ((ct_data *)tree, max_code, s->bl_count);
2827 }
2828
2829 /* ===========================================================================
2830 * Scan a literal or distance tree to determine the frequencies of the codes
2831 * in the bit length tree.
2832 */
2833 local void scan_tree (s, tree, max_code)
2834 deflate_state *s;
2835 ct_data *tree; /* the tree to be scanned */
2836 int max_code; /* and its largest code of non zero frequency */
2837 {
2838 int n; /* iterates over all tree elements */
2839 int prevlen = -1; /* last emitted length */
2840 int curlen; /* length of current code */
2841 int nextlen = tree[0].Len; /* length of next code */
2842 int count = 0; /* repeat count of the current code */
2843 int max_count = 7; /* max repeat count */
2844 int min_count = 4; /* min repeat count */
2845
2846 if (nextlen == 0) max_count = 138, min_count = 3;
2847 tree[max_code+1].Len = (ush)0xffff; /* guard */
2848
2849 for (n = 0; n <= max_code; n++) {
2850 curlen = nextlen; nextlen = tree[n+1].Len;
2851 if (++count < max_count && curlen == nextlen) {
2852 continue;
2853 } else if (count < min_count) {
2854 s->bl_tree[curlen].Freq += count;
2855 } else if (curlen != 0) {
2856 if (curlen != prevlen) s->bl_tree[curlen].Freq++;
2857 s->bl_tree[REP_3_6].Freq++;
2858 } else if (count <= 10) {
2859 s->bl_tree[REPZ_3_10].Freq++;
2860 } else {
2861 s->bl_tree[REPZ_11_138].Freq++;
2862 }
2863 count = 0; prevlen = curlen;
2864 if (nextlen == 0) {
2865 max_count = 138, min_count = 3;
2866 } else if (curlen == nextlen) {
2867 max_count = 6, min_count = 3;
2868 } else {
2869 max_count = 7, min_count = 4;
2870 }
2871 }
2872 }
2873
2874 /* ===========================================================================
2875 * Send a literal or distance tree in compressed form, using the codes in
2876 * bl_tree.
2877 */
2878 local void send_tree (s, tree, max_code)
2879 deflate_state *s;
2880 ct_data *tree; /* the tree to be scanned */
2881 int max_code; /* and its largest code of non zero frequency */
2882 {
2883 int n; /* iterates over all tree elements */
2884 int prevlen = -1; /* last emitted length */
2885 int curlen; /* length of current code */
2886 int nextlen = tree[0].Len; /* length of next code */
2887 int count = 0; /* repeat count of the current code */
2888 int max_count = 7; /* max repeat count */
2889 int min_count = 4; /* min repeat count */
2890
2891 /* tree[max_code+1].Len = -1; */ /* guard already set */
2892 if (nextlen == 0) max_count = 138, min_count = 3;
2893
2894 for (n = 0; n <= max_code; n++) {
2895 curlen = nextlen; nextlen = tree[n+1].Len;
2896 if (++count < max_count && curlen == nextlen) {
2897 continue;
2898 } else if (count < min_count) {
2899 do { send_code(s, curlen, s->bl_tree); } while (--count != 0);
2900
2901 } else if (curlen != 0) {
2902 if (curlen != prevlen) {
2903 send_code(s, curlen, s->bl_tree); count--;
2904 }
2905 Assert(count >= 3 && count <= 6, " 3_6?");
2906 send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2);
2907
2908 } else if (count <= 10) {
2909 send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3);
2910
2911 } else {
2912 send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7);
2913 }
2914 count = 0; prevlen = curlen;
2915 if (nextlen == 0) {
2916 max_count = 138, min_count = 3;
2917 } else if (curlen == nextlen) {
2918 max_count = 6, min_count = 3;
2919 } else {
2920 max_count = 7, min_count = 4;
2921 }
2922 }
2923 }
2924
2925 /* ===========================================================================
2926 * Construct the Huffman tree for the bit lengths and return the index in
2927 * bl_order of the last bit length code to send.
2928 */
2929 local int build_bl_tree(s)
2930 deflate_state *s;
2931 {
2932 int max_blindex; /* index of last bit length code of non zero freq */
2933
2934 /* Determine the bit length frequencies for literal and distance trees */
2935 scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code);
2936 scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code);
2937
2938 /* Build the bit length tree: */
2939 build_tree(s, (tree_desc *)(&(s->bl_desc)));
2940 /* opt_len now includes the length of the tree representations, except
2941 * the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
2942 */
2943
2944 /* Determine the number of bit length codes to send. The pkzip format
2945 * requires that at least 4 bit length codes be sent. (appnote.txt says
2946 * 3 but the actual value used is 4.)
2947 */
2948 for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) {
2949 if (s->bl_tree[bl_order[max_blindex]].Len != 0) break;
2950 }
2951 /* Update opt_len to include the bit length tree and counts */
2952 s->opt_len += 3*(max_blindex+1) + 5+5+4;
2953 Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld",
2954 s->opt_len, s->static_len));
2955
2956 return max_blindex;
2957 }
2958
2959 /* ===========================================================================
2960 * Send the header for a block using dynamic Huffman trees: the counts, the
2961 * lengths of the bit length codes, the literal tree and the distance tree.
2962 * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
2963 */
2964 local void send_all_trees(s, lcodes, dcodes, blcodes)
2965 deflate_state *s;
2966 int lcodes, dcodes, blcodes; /* number of codes for each tree */
2967 {
2968 int rank; /* index in bl_order */
2969
2970 Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
2971 Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
2972 "too many codes");
2973 Tracev((stderr, "\nbl counts: "));
2974 send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */
2975 send_bits(s, dcodes-1, 5);
2976 send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */
2977 for (rank = 0; rank < blcodes; rank++) {
2978 Tracev((stderr, "\nbl code %2d ", bl_order[rank]));
2979 send_bits(s, s->bl_tree[bl_order[rank]].Len, 3);
2980 }
2981 Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent));
2982
2983 send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */
2984 Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent));
2985
2986 send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */
2987 Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent));
2988 }
2989
2990 /* ===========================================================================
2991 * Send a stored block
2992 */
2993 void _tr_stored_block(s, buf, stored_len, eof)
2994 deflate_state *s;
2995 charf *buf; /* input block */
2996 ulg stored_len; /* length of input block */
2997 int eof; /* true if this is the last block for a file */
2998 {
2999 send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */
3000 #ifdef DEBUG_ZLIB
3001 s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L;
3002 s->compressed_len += (stored_len + 4) << 3;
3003 #endif
3004 copy_block(s, buf, (unsigned)stored_len, 1); /* with header */
3005 }
3006
3007 /* ===========================================================================
3008 * Send one empty static block to give enough lookahead for inflate.
3009 * This takes 10 bits, of which 7 may remain in the bit buffer.
3010 * The current inflate code requires 9 bits of lookahead. If the
3011 * last two codes for the previous block (real code plus EOB) were coded
3012 * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode
3013 * the last real code. In this case we send two empty static blocks instead
3014 * of one. (There are no problems if the previous block is stored or fixed.)
3015 * To simplify the code, we assume the worst case of last real code encoded
3016 * on one bit only.
3017 */
3018 void _tr_align(s)
3019 deflate_state *s;
3020 {
3021 send_bits(s, STATIC_TREES<<1, 3);
3022 send_code(s, END_BLOCK, static_ltree);
3023 #ifdef DEBUG_ZLIB
3024 s->compressed_len += 10L; /* 3 for block type, 7 for EOB */
3025 #endif
3026 bi_flush(s);
3027 /* Of the 10 bits for the empty block, we have already sent
3028 * (10 - bi_valid) bits. The lookahead for the last real code (before
3029 * the EOB of the previous block) was thus at least one plus the length
3030 * of the EOB plus what we have just sent of the empty static block.
3031 */
3032 if (1 + s->last_eob_len + 10 - s->bi_valid < 9) {
3033 send_bits(s, STATIC_TREES<<1, 3);
3034 send_code(s, END_BLOCK, static_ltree);
3035 #ifdef DEBUG_ZLIB
3036 s->compressed_len += 10L;
3037 #endif
3038 bi_flush(s);
3039 }
3040 s->last_eob_len = 7;
3041 }
3042
3043 /* ===========================================================================
3044 * Determine the best encoding for the current block: dynamic trees, static
3045 * trees or store, and output the encoded block to the zip file.
3046 */
3047 void _tr_flush_block(s, buf, stored_len, eof)
3048 deflate_state *s;
3049 charf *buf; /* input block, or NULL if too old */
3050 ulg stored_len; /* length of input block */
3051 int eof; /* true if this is the last block for a file */
3052 {
3053 ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
3054 int max_blindex = 0; /* index of last bit length code of non zero freq */
3055
3056 /* Build the Huffman trees unless a stored block is forced */
3057 if (s->level > 0) {
3058
3059 /* Check if the file is ascii or binary */
3060 if (s->data_type == Z_UNKNOWN) set_data_type(s);
3061
3062 /* Construct the literal and distance trees */
3063 build_tree(s, (tree_desc *)(&(s->l_desc)));
3064 Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len,
3065 s->static_len));
3066
3067 build_tree(s, (tree_desc *)(&(s->d_desc)));
3068 Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len,
3069 s->static_len));
3070 /* At this point, opt_len and static_len are the total bit lengths of
3071 * the compressed block data, excluding the tree representations.
3072 */
3073
3074 /* Build the bit length tree for the above two trees, and get the index
3075 * in bl_order of the last bit length code to send.
3076 */
3077 max_blindex = build_bl_tree(s);
3078
3079 /* Determine the best encoding. Compute first the block length in bytes*/
3080 opt_lenb = (s->opt_len+3+7)>>3;
3081 static_lenb = (s->static_len+3+7)>>3;
3082
3083 Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
3084 opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
3085 s->last_lit));
3086
3087 if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
3088
3089 } else {
3090 Assert(buf != (char*)0, "lost buf");
3091 opt_lenb = static_lenb = stored_len + 5; /* force a stored block */
3092 }
3093
3094 #ifdef FORCE_STORED
3095 if (buf != (char*)0) { /* force stored block */
3096 #else
3097 if (stored_len+4 <= opt_lenb && buf != (char*)0) {
3098 /* 4: two words for the lengths */
3099 #endif
3100 /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
3101 * Otherwise we can't have processed more than WSIZE input bytes since
3102 * the last block flush, because compression would have been
3103 * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
3104 * transform a block into a stored block.
3105 */
3106 _tr_stored_block(s, buf, stored_len, eof);
3107
3108 #ifdef FORCE_STATIC
3109 } else if (static_lenb >= 0) { /* force static trees */
3110 #else
3111 } else if (static_lenb == opt_lenb) {
3112 #endif
3113 send_bits(s, (STATIC_TREES<<1)+eof, 3);
3114 compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree);
3115 #ifdef DEBUG_ZLIB
3116 s->compressed_len += 3 + s->static_len;
3117 #endif
3118 } else {
3119 send_bits(s, (DYN_TREES<<1)+eof, 3);
3120 send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1,
3121 max_blindex+1);
3122 compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree);
3123 #ifdef DEBUG_ZLIB
3124 s->compressed_len += 3 + s->opt_len;
3125 #endif
3126 }
3127 Assert (s->compressed_len == s->bits_sent, "bad compressed size");
3128 /* The above check is made mod 2^32, for files larger than 512 MB
3129 * and uLong implemented on 32 bits.
3130 */
3131 init_block(s);
3132
3133 if (eof) {
3134 bi_windup(s);
3135 #ifdef DEBUG_ZLIB
3136 s->compressed_len += 7; /* align on byte boundary */
3137 #endif
3138 }
3139 Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3,
3140 s->compressed_len-7*eof));
3141 }
3142
3143 /* ===========================================================================
3144 * Save the match info and tally the frequency counts. Return true if
3145 * the current block must be flushed.
3146 */
3147 int _tr_tally (s, dist, lc)
3148 deflate_state *s;
3149 unsigned dist; /* distance of matched string */
3150 unsigned lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */
3151 {
3152 s->d_buf[s->last_lit] = (ush)dist;
3153 s->l_buf[s->last_lit++] = (uch)lc;
3154 if (dist == 0) {
3155 /* lc is the unmatched char */
3156 s->dyn_ltree[lc].Freq++;
3157 } else {
3158 s->matches++;
3159 /* Here, lc is the match length - MIN_MATCH */
3160 dist--; /* dist = match distance - 1 */
3161 Assert((ush)dist < (ush)MAX_DIST(s) &&
3162 (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
3163 (ush)d_code(dist) < (ush)D_CODES, "_tr_tally: bad match");
3164
3165 s->dyn_ltree[_length_code[lc]+LITERALS+1].Freq++;
3166 s->dyn_dtree[d_code(dist)].Freq++;
3167 }
3168
3169 #ifdef TRUNCATE_BLOCK
3170 /* Try to guess if it is profitable to stop the current block here */
3171 if ((s->last_lit & 0x1fff) == 0 && s->level > 2) {
3172 /* Compute an upper bound for the compressed length */
3173 ulg out_length = (ulg)s->last_lit*8L;
3174 ulg in_length = (ulg)((long)s->strstart - s->block_start);
3175 int dcode;
3176 for (dcode = 0; dcode < D_CODES; dcode++) {
3177 out_length += (ulg)s->dyn_dtree[dcode].Freq *
3178 (5L+extra_dbits[dcode]);
3179 }
3180 out_length >>= 3;
3181 Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ",
3182 s->last_lit, in_length, out_length,
3183 100L - out_length*100L/in_length));
3184 if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1;
3185 }
3186 #endif
3187 return (s->last_lit == s->lit_bufsize-1);
3188 /* We avoid equality with lit_bufsize because of wraparound at 64K
3189 * on 16 bit machines and because stored blocks are restricted to
3190 * 64K-1 bytes.
3191 */
3192 }
3193
3194 /* ===========================================================================
3195 * Send the block data compressed using the given Huffman trees
3196 */
3197 local void compress_block(s, ltree, dtree)
3198 deflate_state *s;
3199 ct_data *ltree; /* literal tree */
3200 ct_data *dtree; /* distance tree */
3201 {
3202 unsigned dist; /* distance of matched string */
3203 int lc; /* match length or unmatched char (if dist == 0) */
3204 unsigned lx = 0; /* running index in l_buf */
3205 unsigned code; /* the code to send */
3206 int extra; /* number of extra bits to send */
3207
3208 if (s->last_lit != 0) do {
3209 dist = s->d_buf[lx];
3210 lc = s->l_buf[lx++];
3211 if (dist == 0) {
3212 send_code(s, lc, ltree); /* send a literal byte */
3213 Tracecv(isgraph(lc), (stderr," '%c' ", lc));
3214 } else {
3215 /* Here, lc is the match length - MIN_MATCH */
3216 code = _length_code[lc];
3217 send_code(s, code+LITERALS+1, ltree); /* send the length code */
3218 extra = extra_lbits[code];
3219 if (extra != 0) {
3220 lc -= base_length[code];
3221 send_bits(s, lc, extra); /* send the extra length bits */
3222 }
3223 dist--; /* dist is now the match distance - 1 */
3224 code = d_code(dist);
3225 Assert (code < D_CODES, "bad d_code");
3226
3227 send_code(s, code, dtree); /* send the distance code */
3228 extra = extra_dbits[code];
3229 if (extra != 0) {
3230 dist -= base_dist[code];
3231 send_bits(s, dist, extra); /* send the extra distance bits */
3232 }
3233 } /* literal or match pair ? */
3234
3235 /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */
3236 Assert(s->pending < s->lit_bufsize + 2*lx, "pendingBuf overflow");
3237
3238 } while (lx < s->last_lit);
3239
3240 send_code(s, END_BLOCK, ltree);
3241 s->last_eob_len = ltree[END_BLOCK].Len;
3242 }
3243
3244 /* ===========================================================================
3245 * Set the data type to ASCII or BINARY, using a crude approximation:
3246 * binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise.
3247 * IN assertion: the fields freq of dyn_ltree are set and the total of all
3248 * frequencies does not exceed 64K (to fit in an int on 16 bit machines).
3249 */
3250 local void set_data_type(s)
3251 deflate_state *s;
3252 {
3253 int n = 0;
3254 unsigned ascii_freq = 0;
3255 unsigned bin_freq = 0;
3256 while (n < 7) bin_freq += s->dyn_ltree[n++].Freq;
3257 while (n < 128) ascii_freq += s->dyn_ltree[n++].Freq;
3258 while (n < LITERALS) bin_freq += s->dyn_ltree[n++].Freq;
3259 s->data_type = (Byte)(bin_freq > (ascii_freq >> 2) ? Z_BINARY : Z_ASCII);
3260 }
3261
3262 /* ===========================================================================
3263 * Reverse the first len bits of a code, using straightforward code (a faster
3264 * method would use a table)
3265 * IN assertion: 1 <= len <= 15
3266 */
3267 local unsigned bi_reverse(code, len)
3268 unsigned code; /* the value to invert */
3269 int len; /* its bit length */
3270 {
3271 register unsigned res = 0;
3272 do {
3273 res |= code & 1;
3274 code >>= 1, res <<= 1;
3275 } while (--len > 0);
3276 return res >> 1;
3277 }
3278
3279 /* ===========================================================================
3280 * Flush the bit buffer, keeping at most 7 bits in it.
3281 */
3282 local void bi_flush(s)
3283 deflate_state *s;
3284 {
3285 if (s->bi_valid == 16) {
3286 put_short(s, s->bi_buf);
3287 s->bi_buf = 0;
3288 s->bi_valid = 0;
3289 } else if (s->bi_valid >= 8) {
3290 put_byte(s, (Byte)s->bi_buf);
3291 s->bi_buf >>= 8;
3292 s->bi_valid -= 8;
3293 }
3294 }
3295
3296 /* ===========================================================================
3297 * Flush the bit buffer and align the output on a byte boundary
3298 */
3299 local void bi_windup(s)
3300 deflate_state *s;
3301 {
3302 if (s->bi_valid > 8) {
3303 put_short(s, s->bi_buf);
3304 } else if (s->bi_valid > 0) {
3305 put_byte(s, (Byte)s->bi_buf);
3306 }
3307 s->bi_buf = 0;
3308 s->bi_valid = 0;
3309 #ifdef DEBUG_ZLIB
3310 s->bits_sent = (s->bits_sent+7) & ~7;
3311 #endif
3312 }
3313
3314 /* ===========================================================================
3315 * Copy a stored block, storing first the length and its
3316 * one's complement if requested.
3317 */
3318 local void copy_block(s, buf, len, header)
3319 deflate_state *s;
3320 charf *buf; /* the input data */
3321 unsigned len; /* its length */
3322 int header; /* true if block header must be written */
3323 {
3324 bi_windup(s); /* align on byte boundary */
3325 s->last_eob_len = 8; /* enough lookahead for inflate */
3326
3327 if (header) {
3328 put_short(s, (ush)len);
3329 put_short(s, (ush)~len);
3330 #ifdef DEBUG_ZLIB
3331 s->bits_sent += 2*16;
3332 #endif
3333 }
3334 #ifdef DEBUG_ZLIB
3335 s->bits_sent += (ulg)len<<3;
3336 #endif
3337 while (len--) {
3338 put_byte(s, *buf++);
3339 }
3340 }
3341 /* --- trees.c */
3342
3343 /* +++ inflate.c */
3344 /* inflate.c -- zlib interface to inflate modules
3345 * Copyright (C) 1995-2002 Mark Adler
3346 * For conditions of distribution and use, see copyright notice in zlib.h
3347 */
3348
3349 /* #include "zutil.h" */
3350
3351 /* +++ infblock.h */
3352 /* infblock.h -- header to use infblock.c
3353 * Copyright (C) 1995-2002 Mark Adler
3354 * For conditions of distribution and use, see copyright notice in zlib.h
3355 */
3356
3357 /* WARNING: this file should *not* be used by applications. It is
3358 part of the implementation of the compression library and is
3359 subject to change. Applications should only use zlib.h.
3360 */
3361
3362 struct inflate_blocks_state;
3363 typedef struct inflate_blocks_state FAR inflate_blocks_statef;
3364
3365 extern inflate_blocks_statef * inflate_blocks_new OF((
3366 z_streamp z,
3367 check_func c, /* check function */
3368 uInt w)); /* window size */
3369
3370 extern int inflate_blocks OF((
3371 inflate_blocks_statef *,
3372 z_streamp ,
3373 int)); /* initial return code */
3374
3375 extern void inflate_blocks_reset OF((
3376 inflate_blocks_statef *,
3377 z_streamp ,
3378 uLongf *)); /* check value on output */
3379
3380 extern int inflate_blocks_free OF((
3381 inflate_blocks_statef *,
3382 z_streamp));
3383
3384 extern void inflate_set_dictionary OF((
3385 inflate_blocks_statef *s,
3386 const Bytef *d, /* dictionary */
3387 uInt n)); /* dictionary length */
3388
3389 extern int inflate_blocks_sync_point OF((
3390 inflate_blocks_statef *s));
3391 /* --- infblock.h */
3392
3393 #ifndef NO_DUMMY_DECL
3394 struct inflate_blocks_state {int dummy;}; /* for buggy compilers */
3395 #endif
3396
3397 /* inflate private state */
3398 typedef struct inflate_state {
3399
3400 /* mode */
3401 enum {
3402 METHOD, /* waiting for method byte */
3403 FLAG, /* waiting for flag byte */
3404 DICT4, /* four dictionary check bytes to go */
3405 DICT3, /* three dictionary check bytes to go */
3406 DICT2, /* two dictionary check bytes to go */
3407 DICT1, /* one dictionary check byte to go */
3408 DICT0, /* waiting for inflateSetDictionary */
3409 BLOCKS, /* decompressing blocks */
3410 CHECK4, /* four check bytes to go */
3411 CHECK3, /* three check bytes to go */
3412 CHECK2, /* two check bytes to go */
3413 CHECK1, /* one check byte to go */
3414 DONE, /* finished check, done */
3415 BAD} /* got an error--stay here */
3416 mode; /* current inflate mode */
3417
3418 /* mode dependent information */
3419 union {
3420 uInt method; /* if FLAGS, method byte */
3421 struct {
3422 uLong was; /* computed check value */
3423 uLong need; /* stream check value */
3424 } check; /* if CHECK, check values to compare */
3425 uInt marker; /* if BAD, inflateSync's marker bytes count */
3426 } sub; /* submode */
3427
3428 /* mode independent information */
3429 int nowrap; /* flag for no wrapper */
3430 uInt wbits; /* log2(window size) (8..15, defaults to 15) */
3431 inflate_blocks_statef
3432 *blocks; /* current inflate_blocks state */
3433
3434 }inflate_state;
3435
3436
3437 int ZEXPORT inflateReset(z)
3438 z_streamp z;
3439 {
3440 inflate_state* s;
3441 if (z == Z_NULL || z->state == Z_NULL)
3442 return Z_STREAM_ERROR;
3443
3444 s = (inflate_state*)z->state;
3445 z->total_in = z->total_out = 0;
3446 z->msg = Z_NULL;
3447 s->mode = s->nowrap ? BLOCKS : METHOD;
3448 inflate_blocks_reset(s->blocks, z, Z_NULL);
3449 Tracev((stderr, "inflate: reset\n"));
3450 return Z_OK;
3451 }
3452
3453
3454 int ZEXPORT inflateEnd(z)
3455 z_streamp z;
3456 {
3457 if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL)
3458 return Z_STREAM_ERROR;
3459 if (((inflate_state*)z->state)->blocks != Z_NULL)
3460 inflate_blocks_free(((inflate_state*)z->state)->blocks, z);
3461 ZFREE(z, z->state);
3462 z->state = Z_NULL;
3463 Tracev((stderr, "inflate: end\n"));
3464 return Z_OK;
3465 }
3466
3467
3468 int ZEXPORT inflateInit2_(z, w, version, stream_size)
3469 z_streamp z;
3470 int w;
3471 const char *version;
3472 int stream_size;
3473 {
3474 inflate_state* s;
3475 if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
3476 stream_size != sizeof(z_stream))
3477 return Z_VERSION_ERROR;
3478
3479 /* initialize state */
3480 if (z == Z_NULL)
3481 return Z_STREAM_ERROR;
3482 z->msg = Z_NULL;
3483 #ifndef NO_ZCFUNCS
3484 if (z->zalloc == Z_NULL)
3485 {
3486 z->zalloc = zcalloc;
3487 z->opaque = (voidpf)0;
3488 }
3489 if (z->zfree == Z_NULL) z->zfree = zcfree;
3490 #endif
3491 if ((z->state = (struct internal_state FAR *)
3492 ZALLOC(z,1,sizeof(struct inflate_state))) == Z_NULL)
3493 return Z_MEM_ERROR;
3494 s = (inflate_state*)z->state;
3495 s->blocks = Z_NULL;
3496
3497 /* handle undocumented nowrap option (no zlib header or check) */
3498 s->nowrap = 0;
3499 if (w < 0)
3500 {
3501 w = - w;
3502 s->nowrap = 1;
3503 }
3504
3505 /* set window size */
3506 if (w < 8 || w > 15)
3507 {
3508 inflateEnd(z);
3509 return Z_STREAM_ERROR;
3510 }
3511 s->wbits = (uInt)w;
3512
3513 /* create inflate_blocks state */
3514 if ((s->blocks =
3515 inflate_blocks_new(z, s->nowrap ? Z_NULL : adler32, (uInt)1 << w))
3516 == Z_NULL)
3517 {
3518 inflateEnd(z);
3519 return Z_MEM_ERROR;
3520 }
3521 Tracev((stderr, "inflate: allocated\n"));
3522
3523 /* reset state */
3524 inflateReset(z);
3525 return Z_OK;
3526 }
3527
3528
3529 int ZEXPORT inflateInit_(z, version, stream_size)
3530 z_streamp z;
3531 const char *version;
3532 int stream_size;
3533 {
3534 return inflateInit2_(z, DEF_WBITS, version, stream_size);
3535 }
3536
3537
3538 #define NEEDBYTE {if(z->avail_in==0)return r;r=f;}
3539 #define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++)
3540
3541 int ZEXPORT inflate(z, f)
3542 z_streamp z;
3543 int f;
3544 {
3545 int r;
3546 uInt b;
3547 inflate_state* s;
3548
3549 if (z == Z_NULL || z->state == Z_NULL || z->next_in == Z_NULL)
3550 return Z_STREAM_ERROR;
3551 f = f == Z_FINISH ? Z_BUF_ERROR : Z_OK;
3552 r = Z_BUF_ERROR;
3553 s = (inflate_state*)z->state;
3554 while (1) switch (s->mode)
3555 {
3556 case METHOD:
3557 NEEDBYTE
3558 if (((s->sub.method = NEXTBYTE) & 0xf) != Z_DEFLATED)
3559 {
3560 s->mode = BAD;
3561 z->msg = (char*)"unknown compression method";
3562 s->sub.marker = 5; /* can't try inflateSync */
3563 break;
3564 }
3565 if ((s->sub.method >> 4) + 8 > s->wbits)
3566 {
3567 s->mode = BAD;
3568 z->msg = (char*)"invalid window size";
3569 s->sub.marker = 5; /* can't try inflateSync */
3570 break;
3571 }
3572 s->mode = FLAG;
3573 case FLAG:
3574 NEEDBYTE
3575 b = NEXTBYTE;
3576 if (((s->sub.method << 8) + b) % 31)
3577 {
3578 s->mode = BAD;
3579 z->msg = (char*)"incorrect header check";
3580 s->sub.marker = 5; /* can't try inflateSync */
3581 break;
3582 }
3583 Tracev((stderr, "inflate: zlib header ok\n"));
3584 if (!(b & PRESET_DICT))
3585 {
3586 s->mode = BLOCKS;
3587 break;
3588 }
3589 s->mode = DICT4;
3590 case DICT4:
3591 NEEDBYTE
3592 s->sub.check.need = (uLong)NEXTBYTE << 24;
3593 s->mode = DICT3;
3594 case DICT3:
3595 NEEDBYTE
3596 s->sub.check.need += (uLong)NEXTBYTE << 16;
3597 s->mode = DICT2;
3598 case DICT2:
3599 NEEDBYTE
3600 s->sub.check.need += (uLong)NEXTBYTE << 8;
3601 s->mode = DICT1;
3602 case DICT1:
3603 NEEDBYTE
3604 s->sub.check.need += (uLong)NEXTBYTE;
3605 z->adler = s->sub.check.need;
3606 s->mode = DICT0;
3607 return Z_NEED_DICT;
3608 case DICT0:
3609 s->mode = BAD;
3610 z->msg = (char*)"need dictionary";
3611 s->sub.marker = 0; /* can try inflateSync */
3612 return Z_STREAM_ERROR;
3613 case BLOCKS:
3614 r = inflate_blocks(s->blocks, z, r);
3615 if (r == Z_DATA_ERROR)
3616 {
3617 s->mode = BAD;
3618 s->sub.marker = 0; /* can try inflateSync */
3619 break;
3620 }
3621 if (r == Z_OK)
3622 r = f;
3623 if (r != Z_STREAM_END)
3624 return r;
3625 r = f;
3626 inflate_blocks_reset(s->blocks, z, &s->sub.check.was);
3627 if (s->nowrap)
3628 {
3629 s->mode = DONE;
3630 break;
3631 }
3632 s->mode = CHECK4;
3633 case CHECK4:
3634 NEEDBYTE
3635 s->sub.check.need = (uLong)NEXTBYTE << 24;
3636 s->mode = CHECK3;
3637 case CHECK3:
3638 NEEDBYTE
3639 s->sub.check.need += (uLong)NEXTBYTE << 16;
3640 s->mode = CHECK2;
3641 case CHECK2:
3642 NEEDBYTE
3643 s->sub.check.need += (uLong)NEXTBYTE << 8;
3644 s->mode = CHECK1;
3645 case CHECK1:
3646 NEEDBYTE
3647 s->sub.check.need += (uLong)NEXTBYTE;
3648
3649 if (s->sub.check.was != s->sub.check.need)
3650 {
3651 s->mode = BAD;
3652 z->msg = (char*)"incorrect data check";
3653 s->sub.marker = 5; /* can't try inflateSync */
3654 break;
3655 }
3656 Tracev((stderr, "inflate: zlib check ok\n"));
3657 s->mode = DONE;
3658 case DONE:
3659 return Z_STREAM_END;
3660 case BAD:
3661 return Z_DATA_ERROR;
3662 default:
3663 return Z_STREAM_ERROR;
3664 }
3665 #ifdef NEED_DUMMY_RETURN
3666 return Z_STREAM_ERROR; /* Some dumb compilers complain without this */
3667 #endif
3668 }
3669
3670
3671 int ZEXPORT inflateSetDictionary(z, dictionary, dictLength)
3672 z_streamp z;
3673 const Bytef *dictionary;
3674 uInt dictLength;
3675 {
3676 uInt length = dictLength;
3677 inflate_state* s;
3678
3679 if (z == Z_NULL || z->state == Z_NULL || ((inflate_state*)z->state)->mode != DICT0)
3680 return Z_STREAM_ERROR;
3681 s = (inflate_state*)z->state;
3682
3683 if (adler32(1L, dictionary, dictLength) != z->adler) return Z_DATA_ERROR;
3684 z->adler = 1L;
3685
3686 if (length >= ((uInt)1<<s->wbits))
3687 {
3688 length = (1<<s->wbits)-1;
3689 dictionary += dictLength - length;
3690 }
3691 inflate_set_dictionary(s->blocks, dictionary, length);
3692 s->mode = BLOCKS;
3693 return Z_OK;
3694 }
3695
3696
3697 int ZEXPORT inflateSync(z)
3698 z_streamp z;
3699 {
3700 uInt n; /* number of bytes to look at */
3701 Bytef *p; /* pointer to bytes */
3702 uInt m; /* number of marker bytes found in a row */
3703 uLong r, w; /* temporaries to save total_in and total_out */
3704 inflate_state* s;
3705
3706 /* set up */
3707 if (z == Z_NULL || z->state == Z_NULL)
3708 return Z_STREAM_ERROR;
3709 s = (inflate_state*)z->state;
3710 if (s->mode != BAD)
3711 {
3712 s->mode = BAD;
3713 s->sub.marker = 0;
3714 }
3715 if ((n = z->avail_in) == 0)
3716 return Z_BUF_ERROR;
3717 p = z->next_in;
3718 m = s->sub.marker;
3719
3720 /* search */
3721 while (n && m < 4)
3722 {
3723 static const Byte mark[4] = {0, 0, 0xff, 0xff};
3724 if (*p == mark[m])
3725 m++;
3726 else if (*p)
3727 m = 0;
3728 else
3729 m = 4 - m;
3730 p++, n--;
3731 }
3732
3733 /* restore */
3734 z->total_in += p - z->next_in;
3735 z->next_in = p;
3736 z->avail_in = n;
3737 s->sub.marker = m;
3738
3739 /* return no joy or set up to restart on a new block */
3740 if (m != 4)
3741 return Z_DATA_ERROR;
3742 r = z->total_in; w = z->total_out;
3743 inflateReset(z);
3744 z->total_in = r; z->total_out = w;
3745 s->mode = BLOCKS;
3746 return Z_OK;
3747 }
3748
3749
3750 /* Returns true if inflate is currently at the end of a block generated
3751 * by Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
3752 * implementation to provide an additional safety check. PPP uses Z_SYNC_FLUSH
3753 * but removes the length bytes of the resulting empty stored block. When
3754 * decompressing, PPP checks that at the end of input packet, inflate is
3755 * waiting for these length bytes.
3756 */
3757 int ZEXPORT inflateSyncPoint(z)
3758 z_streamp z;
3759 {
3760 if (z == Z_NULL || z->state == Z_NULL || ((inflate_state*)z->state)->blocks == Z_NULL)
3761 return Z_STREAM_ERROR;
3762 return inflate_blocks_sync_point(((inflate_state*)z->state)->blocks);
3763 }
3764 #undef NEEDBYTE
3765 #undef NEXTBYTE
3766 /* --- inflate.c */
3767
3768 /* +++ infblock.c */
3769 /* infblock.c -- interpret and process block types to last block
3770 * Copyright (C) 1995-2002 Mark Adler
3771 * For conditions of distribution and use, see copyright notice in zlib.h
3772 */
3773
3774 /* #include "zutil.h" */
3775 /* #include "infblock.h" */
3776
3777 /* +++ inftrees.h */
3778 /* inftrees.h -- header to use inftrees.c
3779 * Copyright (C) 1995-2002 Mark Adler
3780 * For conditions of distribution and use, see copyright notice in zlib.h
3781 */
3782
3783 /* WARNING: this file should *not* be used by applications. It is
3784 part of the implementation of the compression library and is
3785 subject to change. Applications should only use zlib.h.
3786 */
3787
3788 /* Huffman code lookup table entry--this entry is four bytes for machines
3789 that have 16-bit pointers (e.g. PC's in the small or medium model). */
3790
3791 typedef struct inflate_huft_s FAR inflate_huft;
3792
3793 struct inflate_huft_s {
3794 union {
3795 struct {
3796 Byte Exop; /* number of extra bits or operation */
3797 Byte Bits; /* number of bits in this code or subcode */
3798 } what;
3799 uInt pad; /* pad structure to a power of 2 (4 bytes for */
3800 } word; /* 16-bit, 8 bytes for 32-bit int's) */
3801 uInt base; /* literal, length base, distance base,
3802 or table offset */
3803 };
3804
3805 /* Maximum size of dynamic tree. The maximum found in a long but non-
3806 exhaustive search was 1004 huft structures (850 for length/literals
3807 and 154 for distances, the latter actually the result of an
3808 exhaustive search). The actual maximum is not known, but the
3809 value below is more than safe. */
3810 #define MANY 1440
3811
3812 extern int inflate_trees_bits OF((
3813 uIntf *, /* 19 code lengths */
3814 uIntf *, /* bits tree desired/actual depth */
3815 inflate_huft * FAR *, /* bits tree result */
3816 inflate_huft *, /* space for trees */
3817 z_streamp)); /* for messages */
3818
3819 extern int inflate_trees_dynamic OF((
3820 uInt, /* number of literal/length codes */
3821 uInt, /* number of distance codes */
3822 uIntf *, /* that many (total) code lengths */
3823 uIntf *, /* literal desired/actual bit depth */
3824 uIntf *, /* distance desired/actual bit depth */
3825 inflate_huft * FAR *, /* literal/length tree result */
3826 inflate_huft * FAR *, /* distance tree result */
3827 inflate_huft *, /* space for trees */
3828 z_streamp)); /* for messages */
3829
3830 extern int inflate_trees_fixed OF((
3831 uIntf *, /* literal desired/actual bit depth */
3832 uIntf *, /* distance desired/actual bit depth */
3833 inflate_huft * FAR *, /* literal/length tree result */
3834 inflate_huft * FAR *, /* distance tree result */
3835 z_streamp)); /* for memory allocation */
3836 /* --- inftrees.h */
3837
3838 /* +++ infcodes.h */
3839 /* infcodes.h -- header to use infcodes.c
3840 * Copyright (C) 1995-2002 Mark Adler
3841 * For conditions of distribution and use, see copyright notice in zlib.h
3842 */
3843
3844 /* WARNING: this file should *not* be used by applications. It is
3845 part of the implementation of the compression library and is
3846 subject to change. Applications should only use zlib.h.
3847 */
3848
3849 struct inflate_codes_state;
3850 typedef struct inflate_codes_state FAR inflate_codes_statef;
3851
3852 extern inflate_codes_statef *inflate_codes_new OF((
3853 uInt, uInt,
3854 inflate_huft *, inflate_huft *,
3855 z_streamp ));
3856
3857 extern int inflate_codes OF((
3858 inflate_blocks_statef *,
3859 z_streamp ,
3860 int));
3861
3862 extern void inflate_codes_free OF((
3863 inflate_codes_statef *,
3864 z_streamp ));
3865
3866 /* --- infcodes.h */
3867
3868 /* +++ infutil.h */
3869 /* infutil.h -- types and macros common to blocks and codes
3870 * Copyright (C) 1995-2002 Mark Adler
3871 * For conditions of distribution and use, see copyright notice in zlib.h
3872 */
3873
3874 /* WARNING: this file should *not* be used by applications. It is
3875 part of the implementation of the compression library and is
3876 subject to change. Applications should only use zlib.h.
3877 */
3878
3879 #ifndef _INFUTIL_H
3880 #define _INFUTIL_H
3881
3882 typedef enum {
3883 TYPE, /* get type bits (3, including end bit) */
3884 LENS, /* get lengths for stored */
3885 STORED, /* processing stored block */
3886 TABLE, /* get table lengths */
3887 BTREE, /* get bit lengths tree for a dynamic block */
3888 DTREE, /* get length, distance trees for a dynamic block */
3889 CODES, /* processing fixed or dynamic block */
3890 DRY, /* output remaining window bytes */
3891 DONEB, /* finished last block, done */
3892 BADB} /* got a data error--stuck here */
3893 inflate_block_mode;
3894
3895 /* inflate blocks semi-private state */
3896 struct inflate_blocks_state {
3897
3898 /* mode */
3899 inflate_block_mode mode; /* current inflate_block mode */
3900
3901 /* mode dependent information */
3902 union {
3903 uInt left; /* if STORED, bytes left to copy */
3904 struct {
3905 uInt table; /* table lengths (14 bits) */
3906 uInt index; /* index into blens (or border) */
3907 uIntf *blens; /* bit lengths of codes */
3908 uInt bb; /* bit length tree depth */
3909 inflate_huft *tb; /* bit length decoding tree */
3910 } trees; /* if DTREE, decoding info for trees */
3911 struct {
3912 inflate_codes_statef
3913 *codes;
3914 } decode; /* if CODES, current state */
3915 } sub; /* submode */
3916 uInt last; /* true if this block is the last block */
3917
3918 /* mode independent information */
3919 uInt bitk; /* bits in bit buffer */
3920 uLong bitb; /* bit buffer */
3921 inflate_huft *hufts; /* single malloc for tree space */
3922 Bytef *window; /* sliding window */
3923 Bytef *end; /* one byte after sliding window */
3924 Bytef *read; /* window read pointer */
3925 Bytef *write; /* window write pointer */
3926 check_func checkfn; /* check function */
3927 uLong check; /* check on output */
3928
3929 };
3930
3931
3932 /* defines for inflate input/output */
3933 /* update pointers and return */
3934 #define UPDBITS {s->bitb=b;s->bitk=k;}
3935 #define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;}
3936 #define UPDOUT {s->write=q;}
3937 #define UPDATE {UPDBITS UPDIN UPDOUT}
3938 #define LEAVE {UPDATE return inflate_flush(s,z,r);}
3939 /* get bytes and bits */
3940 #define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;}
3941 #define NEEDBYTE {if(n)r=Z_OK;else LEAVE}
3942 #define NEXTBYTE (n--,*p++)
3943 #define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}}
3944 #define DUMPBITS(j) {b>>=(j);k-=(j);}
3945 /* output bytes */
3946 #define WAVAIL (uInt)(q<s->read?s->read-q-1:s->end-q)
3947 #define LOADOUT {q=s->write;m=(uInt)WAVAIL;}
3948 #define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}}
3949 #define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT}
3950 #define NEEDOUT {if(m==0){WRAP if(m==0){FLUSH WRAP if(m==0) LEAVE}}r=Z_OK;}
3951 #define OUTBYTE(a) {*q++=(Byte)(a);m--;}
3952 /* load local pointers */
3953 #define LOAD {LOADIN LOADOUT}
3954
3955 /* masks for lower bits (size given to avoid silly warnings with Visual C++) */
3956 extern uInt inflate_mask[17];
3957
3958 /* copy as much as possible from the sliding window to the output area */
3959 extern int inflate_flush OF((
3960 inflate_blocks_statef *,
3961 z_streamp ,
3962 int));
3963
3964 #ifndef NO_DUMMY_DECL
3965 struct internal_state {int dummy;}; /* for buggy compilers */
3966 #endif
3967
3968 #endif
3969 /* --- infutil.h */
3970
3971 #ifndef NO_DUMMY_DECL
3972 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
3973 #endif
3974
3975 /* simplify the use of the inflate_huft type with some defines */
3976 #define exop word.what.Exop
3977 #define bits word.what.Bits
3978
3979 /* Table for deflate from PKZIP's appnote.txt. */
3980 local const uInt border[] = { /* Order of the bit length code lengths */
3981 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
3982
3983 /*
3984 Notes beyond the 1.93a appnote.txt:
3985
3986 1. Distance pointers never point before the beginning of the output
3987 stream.
3988 2. Distance pointers can point back across blocks, up to 32k away.
3989 3. There is an implied maximum of 7 bits for the bit length table and
3990 15 bits for the actual data.
3991 4. If only one code exists, then it is encoded using one bit. (Zero
3992 would be more efficient, but perhaps a little confusing.) If two
3993 codes exist, they are coded using one bit each (0 and 1).
3994 5. There is no way of sending zero distance codes--a dummy must be
3995 sent if there are none. (History: a pre 2.0 version of PKZIP would
3996 store blocks with no distance codes, but this was discovered to be
3997 too harsh a criterion.) Valid only for 1.93a. 2.04c does allow
3998 zero distance codes, which is sent as one code of zero bits in
3999 length.
4000 6. There are up to 286 literal/length codes. Code 256 represents the
4001 end-of-block. Note however that the static length tree defines
4002 288 codes just to fill out the Huffman codes. Codes 286 and 287
4003 cannot be used though, since there is no length base or extra bits
4004 defined for them. Similarily, there are up to 30 distance codes.
4005 However, static trees define 32 codes (all 5 bits) to fill out the
4006 Huffman codes, but the last two had better not show up in the data.
4007 7. Unzip can check dynamic Huffman blocks for complete code sets.
4008 The exception is that a single code would not be complete (see #4).
4009 8. The five bits following the block type is really the number of
4010 literal codes sent minus 257.
4011 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
4012 (1+6+6). Therefore, to output three times the length, you output
4013 three codes (1+1+1), whereas to output four times the same length,
4014 you only need two codes (1+3). Hmm.
4015 10. In the tree reconstruction algorithm, Code = Code + Increment
4016 only if BitLength(i) is not zero. (Pretty obvious.)
4017 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19)
4018 12. Note: length code 284 can represent 227-258, but length code 285
4019 really is 258. The last length deserves its own, short code
4020 since it gets used a lot in very redundant files. The length
4021 258 is special since 258 - 3 (the min match length) is 255.
4022 13. The literal/length and distance code bit lengths are read as a
4023 single stream of lengths. It is possible (and advantageous) for
4024 a repeat code (16, 17, or 18) to go across the boundary between
4025 the two sets of lengths.
4026 */
4027
4028
4029 void inflate_blocks_reset(s, z, c)
4030 inflate_blocks_statef *s;
4031 z_streamp z;
4032 uLongf *c;
4033 {
4034 if (c != Z_NULL)
4035 *c = s->check;
4036 if (s->mode == BTREE || s->mode == DTREE)
4037 ZFREE(z, s->sub.trees.blens);
4038 if (s->mode == CODES)
4039 inflate_codes_free(s->sub.decode.codes, z);
4040 s->mode = TYPE;
4041 s->bitk = 0;
4042 s->bitb = 0;
4043 s->read = s->write = s->window;
4044 if (s->checkfn != Z_NULL)
4045 z->adler = s->check = (*s->checkfn)(0L, (const Bytef *)Z_NULL, 0);
4046 Tracev((stderr, "inflate: blocks reset\n"));
4047 }
4048
4049
4050 inflate_blocks_statef *inflate_blocks_new(z, c, w)
4051 z_streamp z;
4052 check_func c;
4053 uInt w;
4054 {
4055 inflate_blocks_statef *s;
4056
4057 if ((s = (inflate_blocks_statef *)ZALLOC
4058 (z,1,sizeof(struct inflate_blocks_state))) == Z_NULL)
4059 return s;
4060 if ((s->hufts =
4061 (inflate_huft *)ZALLOC(z, sizeof(inflate_huft), MANY)) == Z_NULL)
4062 {
4063 ZFREE(z, s);
4064 return Z_NULL;
4065 }
4066 if ((s->window = (Bytef *)ZALLOC(z, 1, w)) == Z_NULL)
4067 {
4068 ZFREE(z, s->hufts);
4069 ZFREE(z, s);
4070 return Z_NULL;
4071 }
4072 s->end = s->window + w;
4073 s->checkfn = c;
4074 s->mode = TYPE;
4075 Tracev((stderr, "inflate: blocks allocated\n"));
4076 inflate_blocks_reset(s, z, Z_NULL);
4077 return s;
4078 }
4079
4080
4081 int inflate_blocks(s, z, r)
4082 inflate_blocks_statef *s;
4083 z_streamp z;
4084 int r;
4085 {
4086 uInt t; /* temporary storage */
4087 uLong b; /* bit buffer */
4088 uInt k; /* bits in bit buffer */
4089 Bytef *p; /* input data pointer */
4090 uInt n; /* bytes available there */
4091 Bytef *q; /* output window write pointer */
4092 uInt m; /* bytes to end of window or read pointer */
4093
4094 /* copy input/output information to locals (UPDATE macro restores) */
4095 LOAD
4096
4097 /* process input based on current state */
4098 while (1) switch (s->mode)
4099 {
4100 case TYPE:
4101 NEEDBITS(3)
4102 t = (uInt)b & 7;
4103 s->last = t & 1;
4104 switch (t >> 1)
4105 {
4106 case 0: /* stored */
4107 Tracev((stderr, "inflate: stored block%s\n",
4108 s->last ? " (last)" : ""));
4109 DUMPBITS(3)
4110 t = k & 7; /* go to byte boundary */
4111 DUMPBITS(t)
4112 s->mode = LENS; /* get length of stored block */
4113 break;
4114 case 1: /* fixed */
4115 Tracev((stderr, "inflate: fixed codes block%s\n",
4116 s->last ? " (last)" : ""));
4117 {
4118 uInt bl, bd;
4119 inflate_huft *tl, *td;
4120
4121 inflate_trees_fixed(&bl, &bd, &tl, &td, z);
4122 s->sub.decode.codes = inflate_codes_new(bl, bd, tl, td, z);
4123 if (s->sub.decode.codes == Z_NULL)
4124 {
4125 r = Z_MEM_ERROR;
4126 LEAVE
4127 }
4128 }
4129 DUMPBITS(3)
4130 s->mode = CODES;
4131 break;
4132 case 2: /* dynamic */
4133 Tracev((stderr, "inflate: dynamic codes block%s\n",
4134 s->last ? " (last)" : ""));
4135 DUMPBITS(3)
4136 s->mode = TABLE;
4137 break;
4138 case 3: /* illegal */
4139 DUMPBITS(3)
4140 s->mode = BADB;
4141 z->msg = (char*)"invalid block type";
4142 r = Z_DATA_ERROR;
4143 LEAVE
4144 }
4145 break;
4146 case LENS:
4147 NEEDBITS(32)
4148 if ((((~b) >> 16) & 0xffff) != (b & 0xffff))
4149 {
4150 s->mode = BADB;
4151 z->msg = (char*)"invalid stored block lengths";
4152 r = Z_DATA_ERROR;
4153 LEAVE
4154 }
4155 s->sub.left = (uInt)b & 0xffff;
4156 b = k = 0; /* dump bits */
4157 Tracev((stderr, "inflate: stored length %u\n", s->sub.left));
4158 s->mode = s->sub.left ? STORED : (s->last ? DRY : TYPE);
4159 break;
4160 case STORED:
4161 if (n == 0)
4162 LEAVE
4163 NEEDOUT
4164 t = s->sub.left;
4165 if (t > n) t = n;
4166 if (t > m) t = m;
4167 zmemcpy(q, p, t);
4168 p += t; n -= t;
4169 q += t; m -= t;
4170 if ((s->sub.left -= t) != 0)
4171 break;
4172 Tracev((stderr, "inflate: stored end, %lu total out\n",
4173 z->total_out + (q >= s->read ? q - s->read :
4174 (s->end - s->read) + (q - s->window))));
4175 s->mode = s->last ? DRY : TYPE;
4176 break;
4177 case TABLE:
4178 NEEDBITS(14)
4179 s->sub.trees.table = t = (uInt)b & 0x3fff;
4180 #ifndef PKZIP_BUG_WORKAROUND
4181 if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29)
4182 {
4183 s->mode = BADB;
4184 z->msg = (char*)"too many length or distance symbols";
4185 r = Z_DATA_ERROR;
4186 LEAVE
4187 }
4188 #endif
4189 t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
4190 if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL)
4191 {
4192 r = Z_MEM_ERROR;
4193 LEAVE
4194 }
4195 DUMPBITS(14)
4196 s->sub.trees.index = 0;
4197 Tracev((stderr, "inflate: table sizes ok\n"));
4198 s->mode = BTREE;
4199 case BTREE:
4200 while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10))
4201 {
4202 NEEDBITS(3)
4203 s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7;
4204 DUMPBITS(3)
4205 }
4206 while (s->sub.trees.index < 19)
4207 s->sub.trees.blens[border[s->sub.trees.index++]] = 0;
4208 s->sub.trees.bb = 7;
4209 t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb,
4210 &s->sub.trees.tb, s->hufts, z);
4211 if (t != Z_OK)
4212 {
4213 r = t;
4214 if (r == Z_DATA_ERROR)
4215 {
4216 ZFREE(z, s->sub.trees.blens);
4217 s->mode = BADB;
4218 }
4219 LEAVE
4220 }
4221 s->sub.trees.index = 0;
4222 Tracev((stderr, "inflate: bits tree ok\n"));
4223 s->mode = DTREE;
4224 case DTREE:
4225 while (t = s->sub.trees.table,
4226 s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f))
4227 {
4228 inflate_huft *h;
4229 uInt i, j, c;
4230
4231 t = s->sub.trees.bb;
4232 NEEDBITS(t)
4233 h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]);
4234 t = h->bits;
4235 c = h->base;
4236 if (c < 16)
4237 {
4238 DUMPBITS(t)
4239 s->sub.trees.blens[s->sub.trees.index++] = c;
4240 }
4241 else /* c == 16..18 */
4242 {
4243 i = c == 18 ? 7 : c - 14;
4244 j = c == 18 ? 11 : 3;
4245 NEEDBITS(t + i)
4246 DUMPBITS(t)
4247 j += (uInt)b & inflate_mask[i];
4248 DUMPBITS(i)
4249 i = s->sub.trees.index;
4250 t = s->sub.trees.table;
4251 if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) ||
4252 (c == 16 && i < 1))
4253 {
4254 ZFREE(z, s->sub.trees.blens);
4255 s->mode = BADB;
4256 z->msg = (char*)"invalid bit length repeat";
4257 r = Z_DATA_ERROR;
4258 LEAVE
4259 }
4260 c = c == 16 ? s->sub.trees.blens[i - 1] : 0;
4261 do {
4262 s->sub.trees.blens[i++] = c;
4263 } while (--j);
4264 s->sub.trees.index = i;
4265 }
4266 }
4267 s->sub.trees.tb = Z_NULL;
4268 {
4269 uInt bl, bd;
4270 inflate_huft *tl, *td;
4271 inflate_codes_statef *c;
4272
4273 bl = 9; /* must be <= 9 for lookahead assumptions */
4274 bd = 6; /* must be <= 9 for lookahead assumptions */
4275 t = s->sub.trees.table;
4276 t = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f),
4277 s->sub.trees.blens, &bl, &bd, &tl, &td,
4278 s->hufts, z);
4279 if (t != Z_OK)
4280 {
4281 if (t == (uInt)Z_DATA_ERROR)
4282 {
4283 ZFREE(z, s->sub.trees.blens);
4284 s->mode = BADB;
4285 }
4286 r = t;
4287 LEAVE
4288 }
4289 Tracev((stderr, "inflate: trees ok\n"));
4290 if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL)
4291 {
4292 r = Z_MEM_ERROR;
4293 LEAVE
4294 }
4295 s->sub.decode.codes = c;
4296 }
4297 ZFREE(z, s->sub.trees.blens);
4298 s->mode = CODES;
4299 case CODES:
4300 UPDATE
4301 if ((r = inflate_codes(s, z, r)) != Z_STREAM_END)
4302 return inflate_flush(s, z, r);
4303 r = Z_OK;
4304 inflate_codes_free(s->sub.decode.codes, z);
4305 LOAD
4306 Tracev((stderr, "inflate: codes end, %lu total out\n",
4307 z->total_out + (q >= s->read ? q - s->read :
4308 (s->end - s->read) + (q - s->window))));
4309 if (!s->last)
4310 {
4311 s->mode = TYPE;
4312 break;
4313 }
4314 s->mode = DRY;
4315 case DRY:
4316 FLUSH
4317 if (s->read != s->write)
4318 LEAVE
4319 s->mode = DONEB;
4320 case DONEB:
4321 r = Z_STREAM_END;
4322 LEAVE
4323 case BADB:
4324 r = Z_DATA_ERROR;
4325 LEAVE
4326 default:
4327 r = Z_STREAM_ERROR;
4328 LEAVE
4329 }
4330 }
4331
4332
4333 int inflate_blocks_free(s, z)
4334 inflate_blocks_statef *s;
4335 z_streamp z;
4336 {
4337 inflate_blocks_reset(s, z, Z_NULL);
4338 ZFREE(z, s->window);
4339 ZFREE(z, s->hufts);
4340 ZFREE(z, s);
4341 Tracev((stderr, "inflate: blocks freed\n"));
4342 return Z_OK;
4343 }
4344
4345
4346 void inflate_set_dictionary(s, d, n)
4347 inflate_blocks_statef *s;
4348 const Bytef *d;
4349 uInt n;
4350 {
4351 zmemcpy(s->window, d, n);
4352 s->read = s->write = s->window + n;
4353 }
4354
4355
4356 /* Returns true if inflate is currently at the end of a block generated
4357 * by Z_SYNC_FLUSH or Z_FULL_FLUSH.
4358 * IN assertion: s != Z_NULL
4359 */
4360 int inflate_blocks_sync_point(s)
4361 inflate_blocks_statef *s;
4362 {
4363 return s->mode == LENS;
4364 }
4365 /* --- infblock.c */
4366
4367 /* +++ inftrees.c */
4368 /* inftrees.c -- generate Huffman trees for efficient decoding
4369 * Copyright (C) 1995-2002 Mark Adler
4370 * For conditions of distribution and use, see copyright notice in zlib.h
4371 */
4372
4373 /* #include "zutil.h" */
4374 /* #include "inftrees.h" */
4375
4376 #if !defined(BUILDFIXED) && !defined(STDC)
4377 # define BUILDFIXED /* non ANSI compilers may not accept inffixed.h */
4378 #endif
4379
4380 const char inflate_copyright[] =
4381 " inflate 1.1.4 Copyright 1995-2002 Mark Adler ";
4382 /*
4383 If you use the zlib library in a product, an acknowledgment is welcome
4384 in the documentation of your product. If for some reason you cannot
4385 include such an acknowledgment, I would appreciate that you keep this
4386 copyright string in the executable of your product.
4387 */
4388
4389 #ifndef NO_DUMMY_DECL
4390 struct internal_state {int dummy;}; /* for buggy compilers */
4391 #endif
4392
4393 /* simplify the use of the inflate_huft type with some defines */
4394 #define exop word.what.Exop
4395 #define bits word.what.Bits
4396
4397
4398 local int huft_build OF((
4399 uIntf *, /* code lengths in bits */
4400 uInt, /* number of codes */
4401 uInt, /* number of "simple" codes */
4402 const uIntf *, /* list of base values for non-simple codes */
4403 const uIntf *, /* list of extra bits for non-simple codes */
4404 inflate_huft * FAR*,/* result: starting table */
4405 uIntf *, /* maximum lookup bits (returns actual) */
4406 inflate_huft *, /* space for trees */
4407 uInt *, /* hufts used in space */
4408 uIntf * )); /* space for values */
4409
4410 /* Tables for deflate from PKZIP's appnote.txt. */
4411 local const uInt cplens[31] = { /* Copy lengths for literal codes 257..285 */
4412 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
4413 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
4414 /* see note #13 above about 258 */
4415 local const uInt cplext[31] = { /* Extra bits for literal codes 257..285 */
4416 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
4417 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 112, 112}; /* 112==invalid */
4418 local const uInt cpdist[30] = { /* Copy offsets for distance codes 0..29 */
4419 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
4420 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
4421 8193, 12289, 16385, 24577};
4422 local const uInt cpdext[30] = { /* Extra bits for distance codes */
4423 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
4424 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
4425 12, 12, 13, 13};
4426
4427 /*
4428 Huffman code decoding is performed using a multi-level table lookup.
4429 The fastest way to decode is to simply build a lookup table whose
4430 size is determined by the longest code. However, the time it takes
4431 to build this table can also be a factor if the data being decoded
4432 is not very long. The most common codes are necessarily the
4433 shortest codes, so those codes dominate the decoding time, and hence
4434 the speed. The idea is you can have a shorter table that decodes the
4435 shorter, more probable codes, and then point to subsidiary tables for
4436 the longer codes. The time it costs to decode the longer codes is
4437 then traded against the time it takes to make longer tables.
4438
4439 This results of this trade are in the variables lbits and dbits
4440 below. lbits is the number of bits the first level table for literal/
4441 length codes can decode in one step, and dbits is the same thing for
4442 the distance codes. Subsequent tables are also less than or equal to
4443 those sizes. These values may be adjusted either when all of the
4444 codes are shorter than that, in which case the longest code length in
4445 bits is used, or when the shortest code is *longer* than the requested
4446 table size, in which case the length of the shortest code in bits is
4447 used.
4448
4449 There are two different values for the two tables, since they code a
4450 different number of possibilities each. The literal/length table
4451 codes 286 possible values, or in a flat code, a little over eight
4452 bits. The distance table codes 30 possible values, or a little less
4453 than five bits, flat. The optimum values for speed end up being
4454 about one bit more than those, so lbits is 8+1 and dbits is 5+1.
4455 The optimum values may differ though from machine to machine, and
4456 possibly even between compilers. Your mileage may vary.
4457 */
4458
4459
4460 /* If BMAX needs to be larger than 16, then h and x[] should be uLong. */
4461 #define BMAX 15 /* maximum bit length of any code */
4462
4463 local int huft_build(b, n, s, d, e, t, m, hp, hn, v)
4464 uIntf *b; /* code lengths in bits (all assumed <= BMAX) */
4465 uInt n; /* number of codes (assumed <= 288) */
4466 uInt s; /* number of simple-valued codes (0..s-1) */
4467 const uIntf *d; /* list of base values for non-simple codes */
4468 const uIntf *e; /* list of extra bits for non-simple codes */
4469 inflate_huft * FAR *t; /* result: starting table */
4470 uIntf *m; /* maximum lookup bits, returns actual */
4471 inflate_huft *hp; /* space for trees */
4472 uInt *hn; /* hufts used in space */
4473 uIntf *v; /* working area: values in order of bit length */
4474 /* Given a list of code lengths and a maximum table size, make a set of
4475 tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR
4476 if the given code set is incomplete (the tables are still built in this
4477 case), or Z_DATA_ERROR if the input is invalid. */
4478 {
4479
4480 uInt a; /* counter for codes of length k */
4481 uInt c[BMAX+1]; /* bit length count table */
4482 uInt f; /* i repeats in table every f entries */
4483 int g; /* maximum code length */
4484 int h; /* table level */
4485 register uInt i; /* counter, current code */
4486 register uInt j; /* counter */
4487 register int k; /* number of bits in current code */
4488 int l; /* bits per table (returned in m) */
4489 uInt mask; /* (1 << w) - 1, to avoid cc -O bug on HP */
4490 register uIntf *p; /* pointer into c[], b[], or v[] */
4491 inflate_huft *q; /* points to current table */
4492 struct inflate_huft_s r; /* table entry for structure assignment */
4493 inflate_huft *u[BMAX]; /* table stack */
4494 register int w; /* bits before this table == (l * h) */
4495 uInt x[BMAX+1]; /* bit offsets, then code stack */
4496 uIntf *xp; /* pointer into x */
4497 int y; /* number of dummy codes added */
4498 uInt z; /* number of entries in current table */
4499
4500
4501 /* Generate counts for each bit length */
4502 p = c;
4503 #define C0 *p++ = 0;
4504 #define C2 C0 C0 C0 C0
4505 #define C4 C2 C2 C2 C2
4506 C4 /* clear c[]--assume BMAX+1 is 16 */
4507 p = b; i = n;
4508 do {
4509 c[*p++]++; /* assume all entries <= BMAX */
4510 } while (--i);
4511 if (c[0] == n) /* null input--all zero length codes */
4512 {
4513 *t = (inflate_huft *)Z_NULL;
4514 *m = 0;
4515 return Z_OK;
4516 }
4517
4518
4519 /* Find minimum and maximum length, bound *m by those */
4520 l = *m;
4521 for (j = 1; j <= BMAX; j++)
4522 if (c[j])
4523 break;
4524 k = j; /* minimum code length */
4525 if ((uInt)l < j)
4526 l = j;
4527 for (i = BMAX; i; i--)
4528 if (c[i])
4529 break;
4530 g = i; /* maximum code length */
4531 if ((uInt)l > i)
4532 l = i;
4533 *m = l;
4534
4535
4536 /* Adjust last length count to fill out codes, if needed */
4537 for (y = 1 << j; j < i; j++, y <<= 1)
4538 if ((y -= c[j]) < 0)
4539 return Z_DATA_ERROR;
4540 if ((y -= c[i]) < 0)
4541 return Z_DATA_ERROR;
4542 c[i] += y;
4543
4544
4545 /* Generate starting offsets into the value table for each length */
4546 x[1] = j = 0;
4547 p = c + 1; xp = x + 2;
4548 while (--i) { /* note that i == g from above */
4549 *xp++ = (j += *p++);
4550 }
4551
4552
4553 /* Make a table of values in order of bit lengths */
4554 p = b; i = 0;
4555 do {
4556 if ((j = *p++) != 0)
4557 v[x[j]++] = i;
4558 } while (++i < n);
4559 n = x[g]; /* set n to length of v */
4560
4561
4562 /* Generate the Huffman codes and for each, make the table entries */
4563 x[0] = i = 0; /* first Huffman code is zero */
4564 p = v; /* grab values in bit order */
4565 h = -1; /* no tables yet--level -1 */
4566 w = -l; /* bits decoded == (l * h) */
4567 u[0] = (inflate_huft *)Z_NULL; /* just to keep compilers happy */
4568 q = (inflate_huft *)Z_NULL; /* ditto */
4569 z = 0; /* ditto */
4570
4571 /* go through the bit lengths (k already is bits in shortest code) */
4572 for (; k <= g; k++)
4573 {
4574 a = c[k];
4575 while (a--)
4576 {
4577 /* here i is the Huffman code of length k bits for value *p */
4578 /* make tables up to required level */
4579 while (k > w + l)
4580 {
4581 h++;
4582 w += l; /* previous table always l bits */
4583
4584 /* compute minimum size table less than or equal to l bits */
4585 z = g - w;
4586 z = z > (uInt)l ? l : z; /* table size upper limit */
4587 if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */
4588 { /* too few codes for k-w bit table */
4589 f -= a + 1; /* deduct codes from patterns left */
4590 xp = c + k;
4591 if (j < z)
4592 while (++j < z) /* try smaller tables up to z bits */
4593 {
4594 if ((f <<= 1) <= *++xp)
4595 break; /* enough codes to use up j bits */
4596 f -= *xp; /* else deduct codes from patterns */
4597 }
4598 }
4599 z = 1 << j; /* table entries for j-bit table */
4600
4601 /* allocate new table */
4602 if (*hn + z > MANY) /* (note: doesn't matter for fixed) */
4603 return Z_DATA_ERROR; /* overflow of MANY */
4604 u[h] = q = hp + *hn;
4605 *hn += z;
4606
4607 /* connect to last table, if there is one */
4608 if (h)
4609 {
4610 x[h] = i; /* save pattern for backing up */
4611 r.bits = (Byte)l; /* bits to dump before this table */
4612 r.exop = (Byte)j; /* bits in this table */
4613 j = i >> (w - l);
4614 r.base = (uInt)(q - u[h-1] - j); /* offset to this table */
4615 u[h-1][j] = r; /* connect to last table */
4616 }
4617 else
4618 *t = q; /* first table is returned result */
4619 }
4620
4621 /* set up table entry in r */
4622 r.bits = (Byte)(k - w);
4623 if (p >= v + n)
4624 r.exop = 128 + 64; /* out of values--invalid code */
4625 else if (*p < s)
4626 {
4627 r.exop = (Byte)(*p < 256 ? 0 : 32 + 64); /* 256 is end-of-block */
4628 r.base = *p++; /* simple code is just the value */
4629 }
4630 else
4631 {
4632 r.exop = (Byte)(e[*p - s] + 16 + 64);/* non-simple--look up in lists */
4633 r.base = d[*p++ - s];
4634 }
4635
4636 /* fill code-like entries with r */
4637 f = 1 << (k - w);
4638 for (j = i >> w; j < z; j += f)
4639 q[j] = r;
4640
4641 /* backwards increment the k-bit code i */
4642 for (j = 1 << (k - 1); i & j; j >>= 1)
4643 i ^= j;
4644 i ^= j;
4645
4646 /* backup over finished tables */
4647 mask = (1 << w) - 1; /* needed on HP, cc -O bug */
4648 while ((i & mask) != x[h])
4649 {
4650 h--; /* don't need to update q */
4651 w -= l;
4652 mask = (1 << w) - 1;
4653 }
4654 }
4655 }
4656
4657
4658 /* Return Z_BUF_ERROR if we were given an incomplete table */
4659 return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK;
4660 }
4661
4662
4663 int inflate_trees_bits(c, bb, tb, hp, z)
4664 uIntf *c; /* 19 code lengths */
4665 uIntf *bb; /* bits tree desired/actual depth */
4666 inflate_huft * FAR *tb; /* bits tree result */
4667 inflate_huft *hp; /* space for trees */
4668 z_streamp z; /* for messages */
4669 {
4670 int r;
4671 uInt hn = 0; /* hufts used in space */
4672 uIntf *v; /* work area for huft_build */
4673
4674 if ((v = (uIntf*)ZALLOC(z, 19, sizeof(uInt))) == Z_NULL)
4675 return Z_MEM_ERROR;
4676 r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL,
4677 tb, bb, hp, &hn, v);
4678 if (r == Z_DATA_ERROR)
4679 z->msg = (char*)"oversubscribed dynamic bit lengths tree";
4680 else if (r == Z_BUF_ERROR || *bb == 0)
4681 {
4682 z->msg = (char*)"incomplete dynamic bit lengths tree";
4683 r = Z_DATA_ERROR;
4684 }
4685 ZFREE(z, v);
4686 return r;
4687 }
4688
4689
4690 int inflate_trees_dynamic(nl, nd, c, bl, bd, tl, td, hp, z)
4691 uInt nl; /* number of literal/length codes */
4692 uInt nd; /* number of distance codes */
4693 uIntf *c; /* that many (total) code lengths */
4694 uIntf *bl; /* literal desired/actual bit depth */
4695 uIntf *bd; /* distance desired/actual bit depth */
4696 inflate_huft * FAR *tl; /* literal/length tree result */
4697 inflate_huft * FAR *td; /* distance tree result */
4698 inflate_huft *hp; /* space for trees */
4699 z_streamp z; /* for messages */
4700 {
4701 int r;
4702 uInt hn = 0; /* hufts used in space */
4703 uIntf *v; /* work area for huft_build */
4704
4705 /* allocate work area */
4706 if ((v = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
4707 return Z_MEM_ERROR;
4708
4709 /* build literal/length tree */
4710 r = huft_build(c, nl, 257, cplens, cplext, tl, bl, hp, &hn, v);
4711 if (r != Z_OK || *bl == 0)
4712 {
4713 if (r == Z_DATA_ERROR)
4714 z->msg = (char*)"oversubscribed literal/length tree";
4715 else if (r != Z_MEM_ERROR)
4716 {
4717 z->msg = (char*)"incomplete literal/length tree";
4718 r = Z_DATA_ERROR;
4719 }
4720 ZFREE(z, v);
4721 return r;
4722 }
4723
4724 /* build distance tree */
4725 r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, hp, &hn, v);
4726 if (r != Z_OK || (*bd == 0 && nl > 257))
4727 {
4728 if (r == Z_DATA_ERROR)
4729 z->msg = (char*)"oversubscribed distance tree";
4730 else if (r == Z_BUF_ERROR) {
4731 #ifdef PKZIP_BUG_WORKAROUND
4732 r = Z_OK;
4733 }
4734 #else
4735 z->msg = (char*)"incomplete distance tree";
4736 r = Z_DATA_ERROR;
4737 }
4738 else if (r != Z_MEM_ERROR)
4739 {
4740 z->msg = (char*)"empty distance tree with lengths";
4741 r = Z_DATA_ERROR;
4742 }
4743 ZFREE(z, v);
4744 return r;
4745 #endif
4746 }
4747
4748 /* done */
4749 ZFREE(z, v);
4750 return Z_OK;
4751 }
4752
4753
4754 /* build fixed tables only once--keep them here */
4755 #ifdef BUILDFIXED
4756 local int fixed_built = 0;
4757 #define FIXEDH 544 /* number of hufts used by fixed tables */
4758 local inflate_huft *fixed_mem = NULL;
4759 local uInt fixed_bl;
4760 local uInt fixed_bd;
4761 local inflate_huft *fixed_tl;
4762 local inflate_huft *fixed_td;
4763 #else
4764 /* +++ inffixed.h */
4765 /* inffixed.h -- table for decoding fixed codes
4766 * Generated automatically by the maketree.c program
4767 */
4768
4769 /* WARNING: this file should *not* be used by applications. It is
4770 part of the implementation of the compression library and is
4771 subject to change. Applications should only use zlib.h.
4772 */
4773
4774 local uInt fixed_bl = 9;
4775 local uInt fixed_bd = 5;
4776 local inflate_huft fixed_tl[] = {
4777 {{{96,7}},256}, {{{0,8}},80}, {{{0,8}},16}, {{{84,8}},115},
4778 {{{82,7}},31}, {{{0,8}},112}, {{{0,8}},48}, {{{0,9}},192},
4779 {{{80,7}},10}, {{{0,8}},96}, {{{0,8}},32}, {{{0,9}},160},
4780 {{{0,8}},0}, {{{0,8}},128}, {{{0,8}},64}, {{{0,9}},224},
4781 {{{80,7}},6}, {{{0,8}},88}, {{{0,8}},24}, {{{0,9}},144},
4782 {{{83,7}},59}, {{{0,8}},120}, {{{0,8}},56}, {{{0,9}},208},
4783 {{{81,7}},17}, {{{0,8}},104}, {{{0,8}},40}, {{{0,9}},176},
4784 {{{0,8}},8}, {{{0,8}},136}, {{{0,8}},72}, {{{0,9}},240},
4785 {{{80,7}},4}, {{{0,8}},84}, {{{0,8}},20}, {{{85,8}},227},
4786 {{{83,7}},43}, {{{0,8}},116}, {{{0,8}},52}, {{{0,9}},200},
4787 {{{81,7}},13}, {{{0,8}},100}, {{{0,8}},36}, {{{0,9}},168},
4788 {{{0,8}},4}, {{{0,8}},132}, {{{0,8}},68}, {{{0,9}},232},
4789 {{{80,7}},8}, {{{0,8}},92}, {{{0,8}},28}, {{{0,9}},152},
4790 {{{84,7}},83}, {{{0,8}},124}, {{{0,8}},60}, {{{0,9}},216},
4791 {{{82,7}},23}, {{{0,8}},108}, {{{0,8}},44}, {{{0,9}},184},
4792 {{{0,8}},12}, {{{0,8}},140}, {{{0,8}},76}, {{{0,9}},248},
4793 {{{80,7}},3}, {{{0,8}},82}, {{{0,8}},18}, {{{85,8}},163},
4794 {{{83,7}},35}, {{{0,8}},114}, {{{0,8}},50}, {{{0,9}},196},
4795 {{{81,7}},11}, {{{0,8}},98}, {{{0,8}},34}, {{{0,9}},164},
4796 {{{0,8}},2}, {{{0,8}},130}, {{{0,8}},66}, {{{0,9}},228},
4797 {{{80,7}},7}, {{{0,8}},90}, {{{0,8}},26}, {{{0,9}},148},
4798 {{{84,7}},67}, {{{0,8}},122}, {{{0,8}},58}, {{{0,9}},212},
4799 {{{82,7}},19}, {{{0,8}},106}, {{{0,8}},42}, {{{0,9}},180},
4800 {{{0,8}},10}, {{{0,8}},138}, {{{0,8}},74}, {{{0,9}},244},
4801 {{{80,7}},5}, {{{0,8}},86}, {{{0,8}},22}, {{{192,8}},0},
4802 {{{83,7}},51}, {{{0,8}},118}, {{{0,8}},54}, {{{0,9}},204},
4803 {{{81,7}},15}, {{{0,8}},102}, {{{0,8}},38}, {{{0,9}},172},
4804 {{{0,8}},6}, {{{0,8}},134}, {{{0,8}},70}, {{{0,9}},236},
4805 {{{80,7}},9}, {{{0,8}},94}, {{{0,8}},30}, {{{0,9}},156},
4806 {{{84,7}},99}, {{{0,8}},126}, {{{0,8}},62}, {{{0,9}},220},
4807 {{{82,7}},27}, {{{0,8}},110}, {{{0,8}},46}, {{{0,9}},188},
4808 {{{0,8}},14}, {{{0,8}},142}, {{{0,8}},78}, {{{0,9}},252},
4809 {{{96,7}},256}, {{{0,8}},81}, {{{0,8}},17}, {{{85,8}},131},
4810 {{{82,7}},31}, {{{0,8}},113}, {{{0,8}},49}, {{{0,9}},194},
4811 {{{80,7}},10}, {{{0,8}},97}, {{{0,8}},33}, {{{0,9}},162},
4812 {{{0,8}},1}, {{{0,8}},129}, {{{0,8}},65}, {{{0,9}},226},
4813 {{{80,7}},6}, {{{0,8}},89}, {{{0,8}},25}, {{{0,9}},146},
4814 {{{83,7}},59}, {{{0,8}},121}, {{{0,8}},57}, {{{0,9}},210},
4815 {{{81,7}},17}, {{{0,8}},105}, {{{0,8}},41}, {{{0,9}},178},
4816 {{{0,8}},9}, {{{0,8}},137}, {{{0,8}},73}, {{{0,9}},242},
4817 {{{80,7}},4}, {{{0,8}},85}, {{{0,8}},21}, {{{80,8}},258},
4818 {{{83,7}},43}, {{{0,8}},117}, {{{0,8}},53}, {{{0,9}},202},
4819 {{{81,7}},13}, {{{0,8}},101}, {{{0,8}},37}, {{{0,9}},170},
4820 {{{0,8}},5}, {{{0,8}},133}, {{{0,8}},69}, {{{0,9}},234},
4821 {{{80,7}},8}, {{{0,8}},93}, {{{0,8}},29}, {{{0,9}},154},
4822 {{{84,7}},83}, {{{0,8}},125}, {{{0,8}},61}, {{{0,9}},218},
4823 {{{82,7}},23}, {{{0,8}},109}, {{{0,8}},45}, {{{0,9}},186},
4824 {{{0,8}},13}, {{{0,8}},141}, {{{0,8}},77}, {{{0,9}},250},
4825 {{{80,7}},3}, {{{0,8}},83}, {{{0,8}},19}, {{{85,8}},195},
4826 {{{83,7}},35}, {{{0,8}},115}, {{{0,8}},51}, {{{0,9}},198},
4827 {{{81,7}},11}, {{{0,8}},99}, {{{0,8}},35}, {{{0,9}},166},
4828 {{{0,8}},3}, {{{0,8}},131}, {{{0,8}},67}, {{{0,9}},230},
4829 {{{80,7}},7}, {{{0,8}},91}, {{{0,8}},27}, {{{0,9}},150},
4830 {{{84,7}},67}, {{{0,8}},123}, {{{0,8}},59}, {{{0,9}},214},
4831 {{{82,7}},19}, {{{0,8}},107}, {{{0,8}},43}, {{{0,9}},182},
4832 {{{0,8}},11}, {{{0,8}},139}, {{{0,8}},75}, {{{0,9}},246},
4833 {{{80,7}},5}, {{{0,8}},87}, {{{0,8}},23}, {{{192,8}},0},
4834 {{{83,7}},51}, {{{0,8}},119}, {{{0,8}},55}, {{{0,9}},206},
4835 {{{81,7}},15}, {{{0,8}},103}, {{{0,8}},39}, {{{0,9}},174},
4836 {{{0,8}},7}, {{{0,8}},135}, {{{0,8}},71}, {{{0,9}},238},
4837 {{{80,7}},9}, {{{0,8}},95}, {{{0,8}},31}, {{{0,9}},158},
4838 {{{84,7}},99}, {{{0,8}},127}, {{{0,8}},63}, {{{0,9}},222},
4839 {{{82,7}},27}, {{{0,8}},111}, {{{0,8}},47}, {{{0,9}},190},
4840 {{{0,8}},15}, {{{0,8}},143}, {{{0,8}},79}, {{{0,9}},254},
4841 {{{96,7}},256}, {{{0,8}},80}, {{{0,8}},16}, {{{84,8}},115},
4842 {{{82,7}},31}, {{{0,8}},112}, {{{0,8}},48}, {{{0,9}},193},
4843 {{{80,7}},10}, {{{0,8}},96}, {{{0,8}},32}, {{{0,9}},161},
4844 {{{0,8}},0}, {{{0,8}},128}, {{{0,8}},64}, {{{0,9}},225},
4845 {{{80,7}},6}, {{{0,8}},88}, {{{0,8}},24}, {{{0,9}},145},
4846 {{{83,7}},59}, {{{0,8}},120}, {{{0,8}},56}, {{{0,9}},209},
4847 {{{81,7}},17}, {{{0,8}},104}, {{{0,8}},40}, {{{0,9}},177},
4848 {{{0,8}},8}, {{{0,8}},136}, {{{0,8}},72}, {{{0,9}},241},
4849 {{{80,7}},4}, {{{0,8}},84}, {{{0,8}},20}, {{{85,8}},227},
4850 {{{83,7}},43}, {{{0,8}},116}, {{{0,8}},52}, {{{0,9}},201},
4851 {{{81,7}},13}, {{{0,8}},100}, {{{0,8}},36}, {{{0,9}},169},
4852 {{{0,8}},4}, {{{0,8}},132}, {{{0,8}},68}, {{{0,9}},233},
4853 {{{80,7}},8}, {{{0,8}},92}, {{{0,8}},28}, {{{0,9}},153},
4854 {{{84,7}},83}, {{{0,8}},124}, {{{0,8}},60}, {{{0,9}},217},
4855 {{{82,7}},23}, {{{0,8}},108}, {{{0,8}},44}, {{{0,9}},185},
4856 {{{0,8}},12}, {{{0,8}},140}, {{{0,8}},76}, {{{0,9}},249},
4857 {{{80,7}},3}, {{{0,8}},82}, {{{0,8}},18}, {{{85,8}},163},
4858 {{{83,7}},35}, {{{0,8}},114}, {{{0,8}},50}, {{{0,9}},197},
4859 {{{81,7}},11}, {{{0,8}},98}, {{{0,8}},34}, {{{0,9}},165},
4860 {{{0,8}},2}, {{{0,8}},130}, {{{0,8}},66}, {{{0,9}},229},
4861 {{{80,7}},7}, {{{0,8}},90}, {{{0,8}},26}, {{{0,9}},149},
4862 {{{84,7}},67}, {{{0,8}},122}, {{{0,8}},58}, {{{0,9}},213},
4863 {{{82,7}},19}, {{{0,8}},106}, {{{0,8}},42}, {{{0,9}},181},
4864 {{{0,8}},10}, {{{0,8}},138}, {{{0,8}},74}, {{{0,9}},245},
4865 {{{80,7}},5}, {{{0,8}},86}, {{{0,8}},22}, {{{192,8}},0},
4866 {{{83,7}},51}, {{{0,8}},118}, {{{0,8}},54}, {{{0,9}},205},
4867 {{{81,7}},15}, {{{0,8}},102}, {{{0,8}},38}, {{{0,9}},173},
4868 {{{0,8}},6}, {{{0,8}},134}, {{{0,8}},70}, {{{0,9}},237},
4869 {{{80,7}},9}, {{{0,8}},94}, {{{0,8}},30}, {{{0,9}},157},
4870 {{{84,7}},99}, {{{0,8}},126}, {{{0,8}},62}, {{{0,9}},221},
4871 {{{82,7}},27}, {{{0,8}},110}, {{{0,8}},46}, {{{0,9}},189},
4872 {{{0,8}},14}, {{{0,8}},142}, {{{0,8}},78}, {{{0,9}},253},
4873 {{{96,7}},256}, {{{0,8}},81}, {{{0,8}},17}, {{{85,8}},131},
4874 {{{82,7}},31}, {{{0,8}},113}, {{{0,8}},49}, {{{0,9}},195},
4875 {{{80,7}},10}, {{{0,8}},97}, {{{0,8}},33}, {{{0,9}},163},
4876 {{{0,8}},1}, {{{0,8}},129}, {{{0,8}},65}, {{{0,9}},227},
4877 {{{80,7}},6}, {{{0,8}},89}, {{{0,8}},25}, {{{0,9}},147},
4878 {{{83,7}},59}, {{{0,8}},121}, {{{0,8}},57}, {{{0,9}},211},
4879 {{{81,7}},17}, {{{0,8}},105}, {{{0,8}},41}, {{{0,9}},179},
4880 {{{0,8}},9}, {{{0,8}},137}, {{{0,8}},73}, {{{0,9}},243},
4881 {{{80,7}},4}, {{{0,8}},85}, {{{0,8}},21}, {{{80,8}},258},
4882 {{{83,7}},43}, {{{0,8}},117}, {{{0,8}},53}, {{{0,9}},203},
4883 {{{81,7}},13}, {{{0,8}},101}, {{{0,8}},37}, {{{0,9}},171},
4884 {{{0,8}},5}, {{{0,8}},133}, {{{0,8}},69}, {{{0,9}},235},
4885 {{{80,7}},8}, {{{0,8}},93}, {{{0,8}},29}, {{{0,9}},155},
4886 {{{84,7}},83}, {{{0,8}},125}, {{{0,8}},61}, {{{0,9}},219},
4887 {{{82,7}},23}, {{{0,8}},109}, {{{0,8}},45}, {{{0,9}},187},
4888 {{{0,8}},13}, {{{0,8}},141}, {{{0,8}},77}, {{{0,9}},251},
4889 {{{80,7}},3}, {{{0,8}},83}, {{{0,8}},19}, {{{85,8}},195},
4890 {{{83,7}},35}, {{{0,8}},115}, {{{0,8}},51}, {{{0,9}},199},
4891 {{{81,7}},11}, {{{0,8}},99}, {{{0,8}},35}, {{{0,9}},167},
4892 {{{0,8}},3}, {{{0,8}},131}, {{{0,8}},67}, {{{0,9}},231},
4893 {{{80,7}},7}, {{{0,8}},91}, {{{0,8}},27}, {{{0,9}},151},
4894 {{{84,7}},67}, {{{0,8}},123}, {{{0,8}},59}, {{{0,9}},215},
4895 {{{82,7}},19}, {{{0,8}},107}, {{{0,8}},43}, {{{0,9}},183},
4896 {{{0,8}},11}, {{{0,8}},139}, {{{0,8}},75}, {{{0,9}},247},
4897 {{{80,7}},5}, {{{0,8}},87}, {{{0,8}},23}, {{{192,8}},0},
4898 {{{83,7}},51}, {{{0,8}},119}, {{{0,8}},55}, {{{0,9}},207},
4899 {{{81,7}},15}, {{{0,8}},103}, {{{0,8}},39}, {{{0,9}},175},
4900 {{{0,8}},7}, {{{0,8}},135}, {{{0,8}},71}, {{{0,9}},239},
4901 {{{80,7}},9}, {{{0,8}},95}, {{{0,8}},31}, {{{0,9}},159},
4902 {{{84,7}},99}, {{{0,8}},127}, {{{0,8}},63}, {{{0,9}},223},
4903 {{{82,7}},27}, {{{0,8}},111}, {{{0,8}},47}, {{{0,9}},191},
4904 {{{0,8}},15}, {{{0,8}},143}, {{{0,8}},79}, {{{0,9}},255}
4905 };
4906 local inflate_huft fixed_td[] = {
4907 {{{80,5}},1}, {{{87,5}},257}, {{{83,5}},17}, {{{91,5}},4097},
4908 {{{81,5}},5}, {{{89,5}},1025}, {{{85,5}},65}, {{{93,5}},16385},
4909 {{{80,5}},3}, {{{88,5}},513}, {{{84,5}},33}, {{{92,5}},8193},
4910 {{{82,5}},9}, {{{90,5}},2049}, {{{86,5}},129}, {{{192,5}},24577},
4911 {{{80,5}},2}, {{{87,5}},385}, {{{83,5}},25}, {{{91,5}},6145},
4912 {{{81,5}},7}, {{{89,5}},1537}, {{{85,5}},97}, {{{93,5}},24577},
4913 {{{80,5}},4}, {{{88,5}},769}, {{{84,5}},49}, {{{92,5}},12289},
4914 {{{82,5}},13}, {{{90,5}},3073}, {{{86,5}},193}, {{{192,5}},24577}
4915 };
4916 /* --- inffixed.h */
4917 #endif
4918
4919
4920 int inflate_trees_fixed(bl, bd, tl, td, z)
4921 uIntf *bl; /* literal desired/actual bit depth */
4922 uIntf *bd; /* distance desired/actual bit depth */
4923 inflate_huft * FAR *tl; /* literal/length tree result */
4924 inflate_huft * FAR *td; /* distance tree result */
4925 z_streamp z; /* for memory allocation */
4926 {
4927 #ifdef BUILDFIXED
4928 /* build fixed tables if not already */
4929 if (!fixed_built)
4930 {
4931 int k; /* temporary variable */
4932 uInt f = 0; /* number of hufts used in fixed_mem */
4933 uIntf *c; /* length list for huft_build */
4934 uIntf *v; /* work area for huft_build */
4935
4936 /* allocate memory */
4937 if ((c = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
4938 return Z_MEM_ERROR;
4939 if ((v = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
4940 {
4941 ZFREE(z, c);
4942 return Z_MEM_ERROR;
4943 }
4944
4945 if ((fixed_mem = (inflate_huft*)ZALLOC(z, FIXEDH, sizeof(inflate_huft))) == Z_NULL)
4946 {
4947 ZFREE(z, c);
4948 ZFREE(z, v);
4949 return Z_MEM_ERROR;
4950 }
4951
4952 /* literal table */
4953 for (k = 0; k < 144; k++)
4954 c[k] = 8;
4955 for (; k < 256; k++)
4956 c[k] = 9;
4957 for (; k < 280; k++)
4958 c[k] = 7;
4959 for (; k < 288; k++)
4960 c[k] = 8;
4961 fixed_bl = 9;
4962 huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl,
4963 fixed_mem, &f, v);
4964
4965 /* distance table */
4966 for (k = 0; k < 30; k++)
4967 c[k] = 5;
4968 fixed_bd = 5;
4969 huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd,
4970 fixed_mem, &f, v);
4971
4972 /* done */
4973 ZFREE(z, v);
4974 ZFREE(z, c);
4975 fixed_built = 1;
4976 }
4977 #endif
4978 *bl = fixed_bl;
4979 *bd = fixed_bd;
4980 *tl = fixed_tl;
4981 *td = fixed_td;
4982 return Z_OK;
4983 }
4984 /* --- inftrees.c */
4985
4986 /* +++ infcodes.c */
4987 /* infcodes.c -- process literals and length/distance pairs
4988 * Copyright (C) 1995-2002 Mark Adler
4989 * For conditions of distribution and use, see copyright notice in zlib.h
4990 */
4991
4992 /* #include "zutil.h" */
4993 /* #include "inftrees.h" */
4994 /* #include "infblock.h" */
4995 /* #include "infcodes.h" */
4996 /* #include "infutil.h" */
4997
4998 /* +++ inffast.h */
4999 /* inffast.h -- header to use inffast.c
5000 * Copyright (C) 1995-2002 Mark Adler
5001 * For conditions of distribution and use, see copyright notice in zlib.h
5002 */
5003
5004 /* WARNING: this file should *not* be used by applications. It is
5005 part of the implementation of the compression library and is
5006 subject to change. Applications should only use zlib.h.
5007 */
5008
5009 extern int inflate_fast OF((
5010 uInt,
5011 uInt,
5012 inflate_huft *,
5013 inflate_huft *,
5014 inflate_blocks_statef *,
5015 z_streamp ));
5016 /* --- inffast.h */
5017
5018 /* simplify the use of the inflate_huft type with some defines */
5019 #define exop word.what.Exop
5020 #define bits word.what.Bits
5021
5022 typedef enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
5023 START, /* x: set up for LEN */
5024 LEN, /* i: get length/literal/eob next */
5025 LENEXT, /* i: getting length extra (have base) */
5026 DIST, /* i: get distance next */
5027 DISTEXT, /* i: getting distance extra */
5028 COPY, /* o: copying bytes in window, waiting for space */
5029 LIT, /* o: got literal, waiting for output space */
5030 WASH, /* o: got eob, possibly still output waiting */
5031 END, /* x: got eob and all data flushed */
5032 BADCODE} /* x: got error */
5033 inflate_codes_mode;
5034
5035 /* inflate codes private state */
5036 struct inflate_codes_state {
5037
5038 /* mode */
5039 inflate_codes_mode mode; /* current inflate_codes mode */
5040
5041 /* mode dependent information */
5042 uInt len;
5043 union {
5044 struct {
5045 inflate_huft *tree; /* pointer into tree */
5046 uInt need; /* bits needed */
5047 } code; /* if LEN or DIST, where in tree */
5048 uInt lit; /* if LIT, literal */
5049 struct {
5050 uInt get; /* bits to get for extra */
5051 uInt dist; /* distance back to copy from */
5052 } copy; /* if EXT or COPY, where and how much */
5053 } sub; /* submode */
5054
5055 /* mode independent information */
5056 Byte lbits; /* ltree bits decoded per branch */
5057 Byte dbits; /* dtree bits decoder per branch */
5058 inflate_huft *ltree; /* literal/length/eob tree */
5059 inflate_huft *dtree; /* distance tree */
5060
5061 };
5062
5063
5064 inflate_codes_statef *inflate_codes_new(bl, bd, tl, td, z)
5065 uInt bl, bd;
5066 inflate_huft *tl;
5067 inflate_huft *td; /* need separate declaration for Borland C++ */
5068 z_streamp z;
5069 {
5070 inflate_codes_statef *c;
5071
5072 if ((c = (inflate_codes_statef *)
5073 ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL)
5074 {
5075 c->mode = START;
5076 c->lbits = (Byte)bl;
5077 c->dbits = (Byte)bd;
5078 c->ltree = tl;
5079 c->dtree = td;
5080 Tracev((stderr, "inflate: codes new\n"));
5081 }
5082 return c;
5083 }
5084
5085
5086 int inflate_codes(s, z, r)
5087 inflate_blocks_statef *s;
5088 z_streamp z;
5089 int r;
5090 {
5091 uInt j; /* temporary storage */
5092 inflate_huft *t; /* temporary pointer */
5093 uInt e; /* extra bits or operation */
5094 uLong b; /* bit buffer */
5095 uInt k; /* bits in bit buffer */
5096 Bytef *p; /* input data pointer */
5097 uInt n; /* bytes available there */
5098 Bytef *q; /* output window write pointer */
5099 uInt m; /* bytes to end of window or read pointer */
5100 Bytef *f; /* pointer to copy strings from */
5101 inflate_codes_statef *c = s->sub.decode.codes; /* codes state */
5102
5103 /* copy input/output information to locals (UPDATE macro restores) */
5104 LOAD
5105
5106 /* process input and output based on current state */
5107 while (1) switch (c->mode)
5108 { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
5109 case START: /* x: set up for LEN */
5110 #ifndef SLOW
5111 if (m >= 258 && n >= 10)
5112 {
5113 UPDATE
5114 r = inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z);
5115 LOAD
5116 if (r != Z_OK)
5117 {
5118 c->mode = r == Z_STREAM_END ? WASH : BADCODE;
5119 break;
5120 }
5121 }
5122 #endif /* !SLOW */
5123 c->sub.code.need = c->lbits;
5124 c->sub.code.tree = c->ltree;
5125 c->mode = LEN;
5126 case LEN: /* i: get length/literal/eob next */
5127 j = c->sub.code.need;
5128 NEEDBITS(j)
5129 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
5130 DUMPBITS(t->bits)
5131 e = (uInt)(t->exop);
5132 if (e == 0) /* literal */
5133 {
5134 c->sub.lit = t->base;
5135 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5136 "inflate: literal '%c'\n" :
5137 "inflate: literal 0x%02x\n", t->base));
5138 c->mode = LIT;
5139 break;
5140 }
5141 if (e & 16) /* length */
5142 {
5143 c->sub.copy.get = e & 15;
5144 c->len = t->base;
5145 c->mode = LENEXT;
5146 break;
5147 }
5148 if ((e & 64) == 0) /* next table */
5149 {
5150 c->sub.code.need = e;
5151 c->sub.code.tree = t + t->base;
5152 break;
5153 }
5154 if (e & 32) /* end of block */
5155 {
5156 Tracevv((stderr, "inflate: end of block\n"));
5157 c->mode = WASH;
5158 break;
5159 }
5160 c->mode = BADCODE; /* invalid code */
5161 z->msg = (char*)"invalid literal/length code";
5162 r = Z_DATA_ERROR;
5163 LEAVE
5164 case LENEXT: /* i: getting length extra (have base) */
5165 j = c->sub.copy.get;
5166 NEEDBITS(j)
5167 c->len += (uInt)b & inflate_mask[j];
5168 DUMPBITS(j)
5169 c->sub.code.need = c->dbits;
5170 c->sub.code.tree = c->dtree;
5171 Tracevv((stderr, "inflate: length %u\n", c->len));
5172 c->mode = DIST;
5173 case DIST: /* i: get distance next */
5174 j = c->sub.code.need;
5175 NEEDBITS(j)
5176 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
5177 DUMPBITS(t->bits)
5178 e = (uInt)(t->exop);
5179 if (e & 16) /* distance */
5180 {
5181 c->sub.copy.get = e & 15;
5182 c->sub.copy.dist = t->base;
5183 c->mode = DISTEXT;
5184 break;
5185 }
5186 if ((e & 64) == 0) /* next table */
5187 {
5188 c->sub.code.need = e;
5189 c->sub.code.tree = t + t->base;
5190 break;
5191 }
5192 c->mode = BADCODE; /* invalid code */
5193 z->msg = (char*)"invalid distance code";
5194 r = Z_DATA_ERROR;
5195 LEAVE
5196 case DISTEXT: /* i: getting distance extra */
5197 j = c->sub.copy.get;
5198 NEEDBITS(j)
5199 c->sub.copy.dist += (uInt)b & inflate_mask[j];
5200 DUMPBITS(j)
5201 Tracevv((stderr, "inflate: distance %u\n", c->sub.copy.dist));
5202 c->mode = COPY;
5203 case COPY: /* o: copying bytes in window, waiting for space */
5204 f = q - c->sub.copy.dist;
5205 while (f < s->window) /* modulo window size-"while" instead */
5206 f += s->end - s->window; /* of "if" handles invalid distances */
5207 while (c->len)
5208 {
5209 NEEDOUT
5210 OUTBYTE(*f++)
5211 if (f == s->end)
5212 f = s->window;
5213 c->len--;
5214 }
5215 c->mode = START;
5216 break;
5217 case LIT: /* o: got literal, waiting for output space */
5218 NEEDOUT
5219 OUTBYTE(c->sub.lit)
5220 c->mode = START;
5221 break;
5222 case WASH: /* o: got eob, possibly more output */
5223 if (k > 7) /* return unused byte, if any */
5224 {
5225 Assert(k < 16, "inflate_codes grabbed too many bytes")
5226 k -= 8;
5227 n++;
5228 p--; /* can always return one */
5229 }
5230 FLUSH
5231 if (s->read != s->write)
5232 LEAVE
5233 c->mode = END;
5234 case END:
5235 r = Z_STREAM_END;
5236 LEAVE
5237 case BADCODE: /* x: got error */
5238 r = Z_DATA_ERROR;
5239 LEAVE
5240 default:
5241 r = Z_STREAM_ERROR;
5242 LEAVE
5243 }
5244 #ifdef NEED_DUMMY_RETURN
5245 return Z_STREAM_ERROR; /* Some dumb compilers complain without this */
5246 #endif
5247 }
5248
5249
5250 void inflate_codes_free(c, z)
5251 inflate_codes_statef *c;
5252 z_streamp z;
5253 {
5254 ZFREE(z, c);
5255 Tracev((stderr, "inflate: codes free\n"));
5256 }
5257 /* --- infcodes.c */
5258
5259 /* +++ infutil.c */
5260 /* inflate_util.c -- data and routines common to blocks and codes
5261 * Copyright (C) 1995-2002 Mark Adler
5262 * For conditions of distribution and use, see copyright notice in zlib.h
5263 */
5264
5265 /* #include "zutil.h" */
5266 /* #include "infblock.h" */
5267 /* #include "inftrees.h" */
5268 /* #include "infcodes.h" */
5269 /* #include "infutil.h" */
5270
5271 #ifndef NO_DUMMY_DECL
5272 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
5273 #endif
5274
5275 /* And'ing with mask[n] masks the lower n bits */
5276 uInt inflate_mask[17] = {
5277 0x0000,
5278 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
5279 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
5280 };
5281
5282
5283 /* copy as much as possible from the sliding window to the output area */
5284 int inflate_flush(s, z, r)
5285 inflate_blocks_statef *s;
5286 z_streamp z;
5287 int r;
5288 {
5289 uInt n;
5290 Bytef *p;
5291 Bytef *q;
5292
5293 /* local copies of source and destination pointers */
5294 p = z->next_out;
5295 q = s->read;
5296
5297 /* compute number of bytes to copy as far as end of window */
5298 n = (uInt)((q <= s->write ? s->write : s->end) - q);
5299 if (n > z->avail_out) n = z->avail_out;
5300 if (n && r == Z_BUF_ERROR) r = Z_OK;
5301
5302 /* update counters */
5303 z->avail_out -= n;
5304 z->total_out += n;
5305
5306 /* update check information */
5307 if (s->checkfn != Z_NULL)
5308 z->adler = s->check = (*s->checkfn)(s->check, q, n);
5309
5310 /* copy as far as end of window */
5311 zmemcpy(p, q, n);
5312 p += n;
5313 q += n;
5314
5315 /* see if more to copy at beginning of window */
5316 if (q == s->end)
5317 {
5318 /* wrap pointers */
5319 q = s->window;
5320 if (s->write == s->end)
5321 s->write = s->window;
5322
5323 /* compute bytes to copy */
5324 n = (uInt)(s->write - q);
5325 if (n > z->avail_out) n = z->avail_out;
5326 if (n && r == Z_BUF_ERROR) r = Z_OK;
5327
5328 /* update counters */
5329 z->avail_out -= n;
5330 z->total_out += n;
5331
5332 /* update check information */
5333 if (s->checkfn != Z_NULL)
5334 z->adler = s->check = (*s->checkfn)(s->check, q, n);
5335
5336 /* copy */
5337 zmemcpy(p, q, n);
5338 p += n;
5339 q += n;
5340 }
5341
5342 /* update pointers */
5343 z->next_out = p;
5344 s->read = q;
5345
5346 /* done */
5347 return r;
5348 }
5349 /* --- infutil.c */
5350
5351 /* +++ inffast.c */
5352 /* inffast.c -- process literals and length/distance pairs fast
5353 * Copyright (C) 1995-2002 Mark Adler
5354 * For conditions of distribution and use, see copyright notice in zlib.h
5355 */
5356
5357 /* #include "zutil.h" */
5358 /* #include "inftrees.h" */
5359 /* #include "infblock.h" */
5360 /* #include "infcodes.h" */
5361 /* #include "infutil.h" */
5362 /* #include "inffast.h" */
5363
5364 #ifndef NO_DUMMY_DECL
5365 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
5366 #endif
5367
5368 /* simplify the use of the inflate_huft type with some defines */
5369 #define exop word.what.Exop
5370 #define bits word.what.Bits
5371
5372 /* macros for bit input with no checking and for returning unused bytes */
5373 #define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}}
5374 #define UNGRAB {c=z->avail_in-n;c=(k>>3)<c?k>>3:c;n+=c;p-=c;k-=c<<3;}
5375
5376 /* Called with number of bytes left to write in window at least 258
5377 (the maximum string length) and number of input bytes available
5378 at least ten. The ten bytes are six bytes for the longest length/
5379 distance pair plus four bytes for overloading the bit buffer. */
5380
5381 int inflate_fast(bl, bd, tl, td, s, z)
5382 uInt bl, bd;
5383 inflate_huft *tl;
5384 inflate_huft *td; /* need separate declaration for Borland C++ */
5385 inflate_blocks_statef *s;
5386 z_streamp z;
5387 {
5388 inflate_huft *t; /* temporary pointer */
5389 uInt e; /* extra bits or operation */
5390 uLong b; /* bit buffer */
5391 uInt k; /* bits in bit buffer */
5392 Bytef *p; /* input data pointer */
5393 uInt n; /* bytes available there */
5394 Bytef *q; /* output window write pointer */
5395 uInt m; /* bytes to end of window or read pointer */
5396 uInt ml; /* mask for literal/length tree */
5397 uInt md; /* mask for distance tree */
5398 uInt c; /* bytes to copy */
5399 uInt d; /* distance back to copy from */
5400 Bytef *r; /* copy source pointer */
5401
5402 /* load input, output, bit values */
5403 LOAD
5404
5405 /* initialize masks */
5406 ml = inflate_mask[bl];
5407 md = inflate_mask[bd];
5408
5409 /* do until not enough input or output space for fast loop */
5410 do { /* assume called with m >= 258 && n >= 10 */
5411 /* get literal/length code */
5412 GRABBITS(20) /* max bits for literal/length code */
5413 if ((e = (t = tl + ((uInt)b & ml))->exop) == 0)
5414 {
5415 DUMPBITS(t->bits)
5416 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5417 "inflate: * literal '%c'\n" :
5418 "inflate: * literal 0x%02x\n", t->base));
5419 *q++ = (Byte)t->base;
5420 m--;
5421 continue;
5422 }
5423 do {
5424 DUMPBITS(t->bits)
5425 if (e & 16)
5426 {
5427 /* get extra bits for length */
5428 e &= 15;
5429 c = t->base + ((uInt)b & inflate_mask[e]);
5430 DUMPBITS(e)
5431 Tracevv((stderr, "inflate: * length %u\n", c));
5432
5433 /* decode distance base of block to copy */
5434 GRABBITS(15); /* max bits for distance code */
5435 e = (t = td + ((uInt)b & md))->exop;
5436 do {
5437 DUMPBITS(t->bits)
5438 if (e & 16)
5439 {
5440 /* get extra bits to add to distance base */
5441 e &= 15;
5442 GRABBITS(e) /* get extra bits (up to 13) */
5443 d = t->base + ((uInt)b & inflate_mask[e]);
5444 DUMPBITS(e)
5445 Tracevv((stderr, "inflate: * distance %u\n", d));
5446
5447 /* do the copy */
5448 m -= c;
5449 r = q - d;
5450 if (r < s->window) /* wrap if needed */
5451 {
5452 do {
5453 r += s->end - s->window; /* force pointer in window */
5454 } while (r < s->window); /* covers invalid distances */
5455 e = s->end - r;
5456 if (c > e)
5457 {
5458 c -= e; /* wrapped copy */
5459 do {
5460 *q++ = *r++;
5461 } while (--e);
5462 r = s->window;
5463 do {
5464 *q++ = *r++;
5465 } while (--c);
5466 }
5467 else /* normal copy */
5468 {
5469 *q++ = *r++; c--;
5470 *q++ = *r++; c--;
5471 do {
5472 *q++ = *r++;
5473 } while (--c);
5474 }
5475 }
5476 else /* normal copy */
5477 {
5478 *q++ = *r++; c--;
5479 *q++ = *r++; c--;
5480 do {
5481 *q++ = *r++;
5482 } while (--c);
5483 }
5484 break;
5485 }
5486 else if ((e & 64) == 0)
5487 {
5488 t += t->base;
5489 e = (t += ((uInt)b & inflate_mask[e]))->exop;
5490 }
5491 else
5492 {
5493 z->msg = (char*)"invalid distance code";
5494 UNGRAB
5495 UPDATE
5496 return Z_DATA_ERROR;
5497 }
5498 } while (1);
5499 break;
5500 }
5501 if ((e & 64) == 0)
5502 {
5503 t += t->base;
5504 if ((e = (t += ((uInt)b & inflate_mask[e]))->exop) == 0)
5505 {
5506 DUMPBITS(t->bits)
5507 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5508 "inflate: * literal '%c'\n" :
5509 "inflate: * literal 0x%02x\n", t->base));
5510 *q++ = (Byte)t->base;
5511 m--;
5512 break;
5513 }
5514 }
5515 else if (e & 32)
5516 {
5517 Tracevv((stderr, "inflate: * end of block\n"));
5518 UNGRAB
5519 UPDATE
5520 return Z_STREAM_END;
5521 }
5522 else
5523 {
5524 z->msg = (char*)"invalid literal/length code";
5525 UNGRAB
5526 UPDATE
5527 return Z_DATA_ERROR;
5528 }
5529 } while (1);
5530 } while (m >= 258 && n >= 10);
5531
5532 /* not enough input or output--restore pointers and return */
5533 UNGRAB
5534 UPDATE
5535 return Z_OK;
5536 }
5537 /* --- inffast.c */
5538
5539 /* +++ zutil.c */
5540 /* zutil.c -- target dependent utility functions for the compression library
5541 * Copyright (C) 1995-2002 Jean-loup Gailly.
5542 * For conditions of distribution and use, see copyright notice in zlib.h
5543 */
5544
5545 /* @(#) $Id: zlib.c,v 1.10 2004/07/29 19:17:20 lindak Exp $ */
5546
5547 /* #include "zutil.h" */
5548
5549 #ifndef NO_DUMMY_DECL
5550 struct internal_state {int dummy;}; /* for buggy compilers */
5551 #endif
5552
5553 #ifndef STDC
5554 extern void exit OF((int));
5555 #endif
5556
5557 const char *z_errmsg[10] = {
5558 "need dictionary", /* Z_NEED_DICT 2 */
5559 "stream end", /* Z_STREAM_END 1 */
5560 "", /* Z_OK 0 */
5561 "file error", /* Z_ERRNO (-1) */
5562 "stream error", /* Z_STREAM_ERROR (-2) */
5563 "data error", /* Z_DATA_ERROR (-3) */
5564 "insufficient memory", /* Z_MEM_ERROR (-4) */
5565 "buffer error", /* Z_BUF_ERROR (-5) */
5566 "incompatible version",/* Z_VERSION_ERROR (-6) */
5567 ""};
5568
5569
5570 const char * ZEXPORT zlibVersion()
5571 {
5572 return ZLIB_VERSION;
5573 }
5574
5575 #ifdef DEBUG_ZLIB
5576
5577 # ifndef verbose
5578 # define verbose 0
5579 # endif
5580 int z_verbose = verbose;
5581
5582 void z_error (m)
5583 char *m;
5584 {
5585 fprintf(stderr, "%s\n", m);
5586 exit(1);
5587 }
5588 #endif
5589
5590 /* exported to allow conversion of error code to string for compress() and
5591 * uncompress()
5592 */
5593 const char * ZEXPORT zError(err)
5594 int err;
5595 {
5596 return ERR_MSG(err);
5597 }
5598
5599
5600 #ifndef HAVE_MEMCPY
5601
5602 void zmemcpy(dest, source, len)
5603 Bytef* dest;
5604 const Bytef* source;
5605 uInt len;
5606 {
5607 if (len == 0) return;
5608 do {
5609 *dest++ = *source++; /* ??? to be unrolled */
5610 } while (--len != 0);
5611 }
5612
5613 int zmemcmp(s1, s2, len)
5614 const Bytef* s1;
5615 const Bytef* s2;
5616 uInt len;
5617 {
5618 uInt j;
5619
5620 for (j = 0; j < len; j++) {
5621 if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1;
5622 }
5623 return 0;
5624 }
5625
5626 void zmemzero(dest, len)
5627 Bytef* dest;
5628 uInt len;
5629 {
5630 if (len == 0) return;
5631 do {
5632 *dest++ = 0; /* ??? to be unrolled */
5633 } while (--len != 0);
5634 }
5635 #endif
5636
5637 #ifdef __TURBOC__
5638 #if (defined( __BORLANDC__) || !defined(SMALL_MEDIUM)) && !defined(__32BIT__)
5639 /* Small and medium model in Turbo C are for now limited to near allocation
5640 * with reduced MAX_WBITS and MAX_MEM_LEVEL
5641 */
5642 # define MY_ZCALLOC
5643
5644 /* Turbo C malloc() does not allow dynamic allocation of 64K bytes
5645 * and farmalloc(64K) returns a pointer with an offset of 8, so we
5646 * must fix the pointer. Warning: the pointer must be put back to its
5647 * original form in order to free it, use zcfree().
5648 */
5649
5650 #define MAX_PTR 10
5651 /* 10*64K = 640K */
5652
5653 local int next_ptr = 0;
5654
5655 typedef struct ptr_table_s {
5656 voidpf org_ptr;
5657 voidpf new_ptr;
5658 } ptr_table;
5659
5660 local ptr_table table[MAX_PTR];
5661 /* This table is used to remember the original form of pointers
5662 * to large buffers (64K). Such pointers are normalized with a zero offset.
5663 * Since MSDOS is not a preemptive multitasking OS, this table is not
5664 * protected from concurrent access. This hack doesn't work anyway on
5665 * a protected system like OS/2. Use Microsoft C instead.
5666 */
5667
5668 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
5669 {
5670 voidpf buf = opaque; /* just to make some compilers happy */
5671 ulg bsize = (ulg)items*size;
5672
5673 /* If we allocate less than 65520 bytes, we assume that farmalloc
5674 * will return a usable pointer which doesn't have to be normalized.
5675 */
5676 if (bsize < 65520L) {
5677 buf = farmalloc(bsize);
5678 if (*(ush*)&buf != 0) return buf;
5679 } else {
5680 buf = farmalloc(bsize + 16L);
5681 }
5682 if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
5683 table[next_ptr].org_ptr = buf;
5684
5685 /* Normalize the pointer to seg:0 */
5686 *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
5687 *(ush*)&buf = 0;
5688 table[next_ptr++].new_ptr = buf;
5689 return buf;
5690 }
5691
5692 void zcfree (voidpf opaque, voidpf ptr)
5693 {
5694 int n;
5695 if (*(ush*)&ptr != 0) { /* object < 64K */
5696 farfree(ptr);
5697 return;
5698 }
5699 /* Find the original pointer */
5700 for (n = 0; n < next_ptr; n++) {
5701 if (ptr != table[n].new_ptr) continue;
5702
5703 farfree(table[n].org_ptr);
5704 while (++n < next_ptr) {
5705 table[n-1] = table[n];
5706 }
5707 next_ptr--;
5708 return;
5709 }
5710 ptr = opaque; /* just to make some compilers happy */
5711 Assert(0, "zcfree: ptr not found");
5712 }
5713 #endif
5714 #endif /* __TURBOC__ */
5715
5716
5717 #if defined(M_I86) && !defined(__32BIT__)
5718 /* Microsoft C in 16-bit mode */
5719
5720 # define MY_ZCALLOC
5721
5722 #if (!defined(_MSC_VER) || (_MSC_VER <= 600))
5723 # define _halloc halloc
5724 # define _hfree hfree
5725 #endif
5726
5727 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
5728 {
5729 if (opaque) opaque = 0; /* to make compiler happy */
5730 return _halloc((long)items, size);
5731 }
5732
5733 void zcfree (voidpf opaque, voidpf ptr)
5734 {
5735 if (opaque) opaque = 0; /* to make compiler happy */
5736 _hfree(ptr);
5737 }
5738
5739 #endif /* MSC */
5740
5741
5742 #ifndef MY_ZCALLOC /* Any system without a special alloc function */
5743
5744 #ifndef STDC
5745 extern voidp calloc OF((uInt items, uInt size));
5746 extern void free OF((voidpf ptr));
5747 #endif
5748
5749 voidpf zcalloc (opaque, items, size)
5750 voidpf opaque;
5751 unsigned items;
5752 unsigned size;
5753 {
5754 if (opaque) items += size - size; /* make compiler happy */
5755 return (voidpf)calloc(items, size);
5756 }
5757
5758 void zcfree (opaque, ptr)
5759 voidpf opaque;
5760 voidpf ptr;
5761 {
5762 _FREE(ptr);
5763 if (opaque) return; /* make compiler happy */
5764 }
5765
5766 #endif /* MY_ZCALLOC */
5767 /* --- zutil.c */
5768
5769 /* +++ adler32.c */
5770 /* adler32.c -- compute the Adler-32 checksum of a data stream
5771 * Copyright (C) 1995-2002 Mark Adler
5772 * For conditions of distribution and use, see copyright notice in zlib.h
5773 */
5774
5775 /* @(#) $Id: zlib.c,v 1.10 2004/07/29 19:17:20 lindak Exp $ */
5776
5777 /* #include "zlib.h" */
5778
5779 #define BASE 65521L /* largest prime smaller than 65536 */
5780 #define NMAX 5552
5781 /* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
5782
5783 #define DO1(buf,i) {s1 += buf[i]; s2 += s1;}
5784 #define DO2(buf,i) DO1(buf,i); DO1(buf,i+1);
5785 #define DO4(buf,i) DO2(buf,i); DO2(buf,i+2);
5786 #define DO8(buf,i) DO4(buf,i); DO4(buf,i+4);
5787 #define DO16(buf) DO8(buf,0); DO8(buf,8);
5788
5789 /* ========================================================================= */
5790 uLong ZEXPORT adler32(adler, buf, len)
5791 uLong adler;
5792 const Bytef *buf;
5793 uInt len;
5794 {
5795 unsigned long s1 = adler & 0xffff;
5796 unsigned long s2 = (adler >> 16) & 0xffff;
5797 int k;
5798
5799 if (buf == Z_NULL) return 1L;
5800
5801 while (len > 0) {
5802 k = len < NMAX ? len : NMAX;
5803 len -= k;
5804 while (k >= 16) {
5805 DO16(buf);
5806 buf += 16;
5807 k -= 16;
5808 }
5809 if (k != 0) do {
5810 s1 += *buf++;
5811 s2 += s1;
5812 } while (--k);
5813 s1 %= BASE;
5814 s2 %= BASE;
5815 }
5816 return (s2 << 16) | s1;
5817 }
5818 /* --- adler32.c */