zlib.c revision 1.13.4.2 1 /* $NetBSD: zlib.c,v 1.13.4.2 2002/03/16 16:02:09 jdolecek Exp $ */
2 /*
3 * This file is derived from various .h and .c files from the zlib-1.0.4
4 * distribution by Jean-loup Gailly and Mark Adler, with some additions
5 * by Paul Mackerras to aid in implementing Deflate compression and
6 * decompression for PPP packets. See zlib.h for conditions of
7 * distribution and use.
8 *
9 * Changes that have been made include:
10 * - added Z_PACKET_FLUSH (see zlib.h for details)
11 * - added inflateIncomp and deflateOutputPending
12 * - allow strm->next_out to be NULL, meaning discard the output
13 *
14 * $Id: zlib.c,v 1.13.4.2 2002/03/16 16:02:09 jdolecek Exp $
15 */
16
17 /*
18 * ==FILEVERSION 020312==
19 *
20 * This marker is used by the Linux installation script to determine
21 * whether an up-to-date version of this file is already installed.
22 */
23
24 #include <sys/cdefs.h>
25 __KERNEL_RCSID(0, "$NetBSD: zlib.c,v 1.13.4.2 2002/03/16 16:02:09 jdolecek Exp $");
26
27 #define NO_DUMMY_DECL
28 #define NO_ZCFUNCS
29 #define MY_ZCALLOC
30
31 #if defined(__FreeBSD__) && (defined(KERNEL) || defined(_KERNEL))
32 #define inflate inflate_ppp /* FreeBSD already has an inflate :-( */
33 #endif
34
35
36 /* +++ zutil.h */
37
38 /* zutil.h -- internal interface and configuration of the compression library
39 * Copyright (C) 1995-2002 Jean-loup Gailly.
40 * For conditions of distribution and use, see copyright notice in zlib.h
41 */
42
43 /* WARNING: this file should *not* be used by applications. It is
44 part of the implementation of the compression library and is
45 subject to change. Applications should only use zlib.h.
46 */
47
48 /* @(#) $Id: zlib.c,v 1.13.4.2 2002/03/16 16:02:09 jdolecek Exp $ */
49
50 #ifndef _Z_UTIL_H
51 #define _Z_UTIL_H
52
53 #include "zlib.h"
54
55 #if defined(KERNEL) || defined(_KERNEL)
56 /* Assume this is a *BSD or SVR4 kernel */
57 #include <sys/param.h>
58 #include <sys/time.h>
59 #include <sys/systm.h>
60 # define HAVE_MEMCPY
61 #else
62 #if defined(__KERNEL__)
63 /* Assume this is a Linux kernel */
64 #include <linux/string.h>
65 #define HAVE_MEMCPY
66
67 #else /* not kernel */
68
69 #if defined(__NetBSD__) && (defined(_KERNEL) || defined(_STANDALONE))
70
71 /* XXX doesn't seem to need anything at all, but this is for consistency. */
72 # include <lib/libkern/libkern.h>
73
74 #else
75 #ifdef STDC
76 # include <stddef.h>
77 # include <string.h>
78 # include <stdlib.h>
79 #endif
80 #ifdef NO_ERRNO_H
81 extern int errno;
82 #else
83 # include <errno.h>
84 #endif
85 #endif /* __NetBSD__ && _STANDALONE */
86 #endif /* __KERNEL__ */
87 #endif /* _KERNEL || KERNEL */
88
89
90 #ifndef local
91 # define local static
92 #endif
93 /* compile with -Dlocal if your debugger can't find static symbols */
94
95 typedef unsigned char uch;
96 typedef uch FAR uchf;
97 typedef unsigned short ush;
98 typedef ush FAR ushf;
99 typedef unsigned long ulg;
100
101 extern const char *z_errmsg[10]; /* indexed by 2-zlib_error */
102 /* (size given to avoid silly warnings with Visual C++) */
103
104 #define ERR_MSG(err) z_errmsg[Z_NEED_DICT-(err)]
105
106 #define ERR_RETURN(strm,err) \
107 return (strm->msg = (char*)ERR_MSG(err), (err))
108 /* To be used only when the state is known to be valid */
109
110 /* common constants */
111
112 #ifndef DEF_WBITS
113 # define DEF_WBITS MAX_WBITS
114 #endif
115 /* default windowBits for decompression. MAX_WBITS is for compression only */
116
117 #if MAX_MEM_LEVEL >= 8
118 # define DEF_MEM_LEVEL 8
119 #else
120 # define DEF_MEM_LEVEL MAX_MEM_LEVEL
121 #endif
122 /* default memLevel */
123
124 #define STORED_BLOCK 0
125 #define STATIC_TREES 1
126 #define DYN_TREES 2
127 /* The three kinds of block type */
128
129 #define MIN_MATCH 3
130 #define MAX_MATCH 258
131 /* The minimum and maximum match lengths */
132
133 #define PRESET_DICT 0x20 /* preset dictionary flag in zlib header */
134
135 /* target dependencies */
136
137 #ifdef MSDOS
138 # define OS_CODE 0x00
139 # if defined(__TURBOC__) || defined(__BORLANDC__)
140 # if(__STDC__ == 1) && (defined(__LARGE__) || defined(__COMPACT__))
141 /* Allow compilation with ANSI keywords only enabled */
142 void _Cdecl farfree( void *block );
143 void *_Cdecl farmalloc( unsigned long nbytes );
144 # else
145 # include <alloc.h>
146 # endif
147 # else /* MSC or DJGPP */
148 # include <malloc.h>
149 # endif
150 #endif
151
152 #ifdef OS2
153 # define OS_CODE 0x06
154 #endif
155
156 #ifdef WIN32 /* Window 95 & Windows NT */
157 # define OS_CODE 0x0b
158 #endif
159
160 #if defined(VAXC) || defined(VMS)
161 # define OS_CODE 0x02
162 # define F_OPEN(name, mode) \
163 fopen((name), (mode), "mbc=60", "ctx=stm", "rfm=fix", "mrs=512")
164 #endif
165
166 #ifdef AMIGA
167 # define OS_CODE 0x01
168 #endif
169
170 #if defined(ATARI) || defined(atarist)
171 # define OS_CODE 0x05
172 #endif
173
174 #if defined(MACOS) || defined(TARGET_OS_MAC)
175 # define OS_CODE 0x07
176 # if defined(__MWERKS__) && __dest_os != __be_os && __dest_os != __win32_os
177 # include <unix.h> /* for fdopen */
178 # else
179 # ifndef fdopen
180 # define fdopen(fd,mode) NULL /* No fdopen() */
181 # endif
182 # endif
183 #endif
184
185 #ifdef __50SERIES /* Prime/PRIMOS */
186 # define OS_CODE 0x0F
187 #endif
188
189 #ifdef TOPS20
190 # define OS_CODE 0x0a
191 #endif
192
193 #if defined(_BEOS_) || defined(RISCOS)
194 # define fdopen(fd,mode) NULL /* No fdopen() */
195 #endif
196
197 #if (defined(_MSC_VER) && (_MSC_VER > 600))
198 # define fdopen(fd,type) _fdopen(fd,type)
199 #endif
200
201
202 /* Common defaults */
203
204 #ifndef OS_CODE
205 # define OS_CODE 0x03 /* assume Unix */
206 #endif
207
208 #ifndef F_OPEN
209 # define F_OPEN(name, mode) fopen((name), (mode))
210 #endif
211
212 /* functions */
213
214 #ifdef HAVE_STRERROR
215 extern char *strerror __P((int));
216 # define zstrerror(errnum) strerror(errnum)
217 #else
218 # define zstrerror(errnum) ""
219 #endif
220
221 #if defined(pyr)
222 # define NO_MEMCPY
223 #endif
224 #if defined(SMALL_MEDIUM) && !defined(_MSC_VER) && !defined(__SC__)
225 /* Use our own functions for small and medium model with MSC <= 5.0.
226 * You may have to use the same strategy for Borland C (untested).
227 * The __SC__ check is for Symantec.
228 */
229 # define NO_MEMCPY
230 #endif
231 #if defined(STDC) && !defined(HAVE_MEMCPY) && !defined(NO_MEMCPY)
232 # define HAVE_MEMCPY
233 #endif
234 #ifdef HAVE_MEMCPY
235 # ifdef SMALL_MEDIUM /* MSDOS small or medium model */
236 # define zmemcpy _fmemcpy
237 # define zmemcmp _fmemcmp
238 # define zmemzero(dest, len) _fmemset(dest, 0, len)
239 # else
240 # define zmemcpy memcpy
241 # define zmemcmp memcmp
242 # define zmemzero(dest, len) memset(dest, 0, len)
243 # endif
244 #else
245 extern void zmemcpy __P((Bytef* dest, const Bytef* source, uInt len));
246 extern int zmemcmp __P((const Bytef* s1, const Bytef* s2, uInt len));
247 extern void zmemzero __P((Bytef* dest, uInt len));
248 #endif
249
250 /* Diagnostic functions */
251 #if defined(DEBUG_ZLIB) && !defined(_KERNEL) && !defined(_STANDALONE)
252 # include <stdio.h>
253 extern int z_verbose;
254 extern void z_error __P((char *m));
255 # define Assert(cond,msg) {if(!(cond)) z_error(msg);}
256 # define Trace(x) {if (z_verbose>=0) fprintf x ;}
257 # define Tracev(x) {if (z_verbose>0) fprintf x ;}
258 # define Tracevv(x) {if (z_verbose>1) fprintf x ;}
259 # define Tracec(c,x) {if (z_verbose>0 && (c)) fprintf x ;}
260 # define Tracecv(c,x) {if (z_verbose>1 && (c)) fprintf x ;}
261 #else
262 # define Assert(cond,msg)
263 # define Trace(x)
264 # define Tracev(x)
265 # define Tracevv(x)
266 # define Tracec(c,x)
267 # define Tracecv(c,x)
268 #endif
269
270
271 typedef uLong (ZEXPORT *check_func) __P((uLong check, const Bytef *buf,
272 uInt len));
273 voidpf zcalloc __P((voidpf opaque, unsigned items, unsigned size));
274 void zcfree __P((voidpf opaque, voidpf ptr));
275
276 #define ZALLOC(strm, items, size) \
277 (*((strm)->zalloc))((strm)->opaque, (items), (size))
278 #define ZFREE(strm, addr) (*((strm)->zfree))((strm)->opaque, (voidpf)(addr))
279 #define TRY_FREE(s, p) {if (p) ZFREE(s, p);}
280
281 #endif /* _Z_UTIL_H */
282 /* --- zutil.h */
283
284 /* +++ deflate.h */
285
286 /* deflate.h -- internal compression state
287 * Copyright (C) 1995-2002 Jean-loup Gailly
288 * For conditions of distribution and use, see copyright notice in zlib.h
289 */
290
291 /* WARNING: this file should *not* be used by applications. It is
292 part of the implementation of the compression library and is
293 subject to change. Applications should only use zlib.h.
294 */
295
296 /* @(#) $Id: zlib.c,v 1.13.4.2 2002/03/16 16:02:09 jdolecek Exp $ */
297
298 #ifndef _DEFLATE_H
299 #define _DEFLATE_H
300
301 /* #include "zutil.h" */
302
303 /* ===========================================================================
304 * Internal compression state.
305 */
306
307 #define LENGTH_CODES 29
308 /* number of length codes, not counting the special END_BLOCK code */
309
310 #define LITERALS 256
311 /* number of literal bytes 0..255 */
312
313 #define L_CODES (LITERALS+1+LENGTH_CODES)
314 /* number of Literal or Length codes, including the END_BLOCK code */
315
316 #define D_CODES 30
317 /* number of distance codes */
318
319 #define BL_CODES 19
320 /* number of codes used to transfer the bit lengths */
321
322 #define HEAP_SIZE (2*L_CODES+1)
323 /* maximum heap size */
324
325 #define MAX_BITS 15
326 /* All codes must not exceed MAX_BITS bits */
327
328 #define INIT_STATE 42
329 #define BUSY_STATE 113
330 #define FINISH_STATE 666
331 /* Stream status */
332
333
334 /* Data structure describing a single value and its code string. */
335 typedef struct ct_data_s {
336 union {
337 ush freq; /* frequency count */
338 ush code; /* bit string */
339 } fc;
340 union {
341 ush dad; /* father node in Huffman tree */
342 ush len; /* length of bit string */
343 } dl;
344 } FAR ct_data;
345
346 #define Freq fc.freq
347 #define Code fc.code
348 #define Dad dl.dad
349 #define Len dl.len
350
351 typedef struct static_tree_desc_s static_tree_desc;
352
353 typedef struct tree_desc_s {
354 ct_data *dyn_tree; /* the dynamic tree */
355 int max_code; /* largest code with non zero frequency */
356 static_tree_desc *stat_desc; /* the corresponding static tree */
357 } FAR tree_desc;
358
359 typedef ush Pos;
360 typedef Pos FAR Posf;
361 typedef unsigned IPos;
362
363 /* A Pos is an index in the character window. We use short instead of int to
364 * save space in the various tables. IPos is used only for parameter passing.
365 */
366
367 typedef struct deflate_state {
368 z_streamp strm; /* pointer back to this zlib stream */
369 int status; /* as the name implies */
370 Bytef *pending_buf; /* output still pending */
371 ulg pending_buf_size; /* size of pending_buf */
372 Bytef *pending_out; /* next pending byte to output to the stream */
373 int pending; /* nb of bytes in the pending buffer */
374 int noheader; /* suppress zlib header and adler32 */
375 Byte data_type; /* UNKNOWN, BINARY or ASCII */
376 Byte method; /* STORED (for zip only) or DEFLATED */
377 int last_flush; /* value of flush param for previous deflate call */
378
379 /* used by deflate.c: */
380
381 uInt w_size; /* LZ77 window size (32K by default) */
382 uInt w_bits; /* log2(w_size) (8..16) */
383 uInt w_mask; /* w_size - 1 */
384
385 Bytef *window;
386 /* Sliding window. Input bytes are read into the second half of the window,
387 * and move to the first half later to keep a dictionary of at least wSize
388 * bytes. With this organization, matches are limited to a distance of
389 * wSize-MAX_MATCH bytes, but this ensures that IO is always
390 * performed with a length multiple of the block size. Also, it limits
391 * the window size to 64K, which is quite useful on MSDOS.
392 * To do: use the user input buffer as sliding window.
393 */
394
395 ulg window_size;
396 /* Actual size of window: 2*wSize, except when the user input buffer
397 * is directly used as sliding window.
398 */
399
400 Posf *prev;
401 /* Link to older string with same hash index. To limit the size of this
402 * array to 64K, this link is maintained only for the last 32K strings.
403 * An index in this array is thus a window index modulo 32K.
404 */
405
406 Posf *head; /* Heads of the hash chains or NIL. */
407
408 uInt ins_h; /* hash index of string to be inserted */
409 uInt hash_size; /* number of elements in hash table */
410 uInt hash_bits; /* log2(hash_size) */
411 uInt hash_mask; /* hash_size-1 */
412
413 uInt hash_shift;
414 /* Number of bits by which ins_h must be shifted at each input
415 * step. It must be such that after MIN_MATCH steps, the oldest
416 * byte no longer takes part in the hash key, that is:
417 * hash_shift * MIN_MATCH >= hash_bits
418 */
419
420 long block_start;
421 /* Window position at the beginning of the current output block. Gets
422 * negative when the window is moved backwards.
423 */
424
425 uInt match_length; /* length of best match */
426 IPos prev_match; /* previous match */
427 int match_available; /* set if previous match exists */
428 uInt strstart; /* start of string to insert */
429 uInt match_start; /* start of matching string */
430 uInt lookahead; /* number of valid bytes ahead in window */
431
432 uInt prev_length;
433 /* Length of the best match at previous step. Matches not greater than this
434 * are discarded. This is used in the lazy match evaluation.
435 */
436
437 uInt max_chain_length;
438 /* To speed up deflation, hash chains are never searched beyond this
439 * length. A higher limit improves compression ratio but degrades the
440 * speed.
441 */
442
443 uInt max_lazy_match;
444 /* Attempt to find a better match only when the current match is strictly
445 * smaller than this value. This mechanism is used only for compression
446 * levels >= 4.
447 */
448 # define max_insert_length max_lazy_match
449 /* Insert new strings in the hash table only if the match length is not
450 * greater than this length. This saves time but degrades compression.
451 * max_insert_length is used only for compression levels <= 3.
452 */
453
454 int level; /* compression level (1..9) */
455 int strategy; /* favor or force Huffman coding*/
456
457 uInt good_match;
458 /* Use a faster search when the previous match is longer than this */
459
460 int nice_match; /* Stop searching when current match exceeds this */
461
462 /* used by trees.c: */
463 /* Didn't use ct_data typedef below to supress compiler warning */
464 struct ct_data_s dyn_ltree[HEAP_SIZE]; /* literal and length tree */
465 struct ct_data_s dyn_dtree[2*D_CODES+1]; /* distance tree */
466 struct ct_data_s bl_tree[2*BL_CODES+1]; /* Huffman tree for bit lengths */
467
468 struct tree_desc_s l_desc; /* desc. for literal tree */
469 struct tree_desc_s d_desc; /* desc. for distance tree */
470 struct tree_desc_s bl_desc; /* desc. for bit length tree */
471
472 ush bl_count[MAX_BITS+1];
473 /* number of codes at each bit length for an optimal tree */
474
475 int heap[2*L_CODES+1]; /* heap used to build the Huffman trees */
476 int heap_len; /* number of elements in the heap */
477 int heap_max; /* element of largest frequency */
478 /* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used.
479 * The same heap array is used to build all trees.
480 */
481
482 uch depth[2*L_CODES+1];
483 /* Depth of each subtree used as tie breaker for trees of equal frequency
484 */
485
486 uchf *l_buf; /* buffer for literals or lengths */
487
488 uInt lit_bufsize;
489 /* Size of match buffer for literals/lengths. There are 4 reasons for
490 * limiting lit_bufsize to 64K:
491 * - frequencies can be kept in 16 bit counters
492 * - if compression is not successful for the first block, all input
493 * data is still in the window so we can still emit a stored block even
494 * when input comes from standard input. (This can also be done for
495 * all blocks if lit_bufsize is not greater than 32K.)
496 * - if compression is not successful for a file smaller than 64K, we can
497 * even emit a stored file instead of a stored block (saving 5 bytes).
498 * This is applicable only for zip (not gzip or zlib).
499 * - creating new Huffman trees less frequently may not provide fast
500 * adaptation to changes in the input data statistics. (Take for
501 * example a binary file with poorly compressible code followed by
502 * a highly compressible string table.) Smaller buffer sizes give
503 * fast adaptation but have of course the overhead of transmitting
504 * trees more frequently.
505 * - I can't count above 4
506 */
507
508 uInt last_lit; /* running index in l_buf */
509
510 ushf *d_buf;
511 /* Buffer for distances. To simplify the code, d_buf and l_buf have
512 * the same number of elements. To use different lengths, an extra flag
513 * array would be necessary.
514 */
515
516 ulg opt_len; /* bit length of current block with optimal trees */
517 ulg static_len; /* bit length of current block with static trees */
518 uInt matches; /* number of string matches in current block */
519 int last_eob_len; /* bit length of EOB code for last block */
520
521 #ifdef DEBUG_ZLIB
522 ulg compressed_len; /* total bit length of compressed file mod 2^32 */
523 ulg bits_sent; /* bit length of compressed data sent mod 2^32 */
524 #endif
525
526 ush bi_buf;
527 /* Output buffer. bits are inserted starting at the bottom (least
528 * significant bits).
529 */
530 int bi_valid;
531 /* Number of valid bits in bi_buf. All bits above the last valid bit
532 * are always zero.
533 */
534
535 } FAR deflate_state;
536
537 /* Output a byte on the stream.
538 * IN assertion: there is enough room in pending_buf.
539 */
540 #define put_byte(s, c) {s->pending_buf[s->pending++] = (c);}
541
542
543 #define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
544 /* Minimum amount of lookahead, except at the end of the input file.
545 * See deflate.c for comments about the MIN_MATCH+1.
546 */
547
548 #define MAX_DIST(s) ((s)->w_size-MIN_LOOKAHEAD)
549 /* In order to simplify the code, particularly on 16 bit machines, match
550 * distances are limited to MAX_DIST instead of WSIZE.
551 */
552
553 /* in trees.c */
554 void _tr_init __P((deflate_state *s));
555 int _tr_tally __P((deflate_state *s, unsigned dist, unsigned lc));
556 void _tr_flush_block __P((deflate_state *s, charf *buf, ulg stored_len,
557 int eof));
558 void _tr_align __P((deflate_state *s));
559 void _tr_stored_block __P((deflate_state *s, charf *buf, ulg stored_len,
560 int eof));
561 void _tr_stored_type_only __P((deflate_state *));
562
563 #define d_code(dist) \
564 ((dist) < 256 ? _dist_code[dist] : _dist_code[256+((dist)>>7)])
565 /* Mapping from a distance to a distance code. dist is the distance - 1 and
566 * must not have side effects. _dist_code[256] and _dist_code[257] are never
567 * used.
568 */
569
570 #ifndef DEBUG_ZLIB
571 /* Inline versions of _tr_tally for speed: */
572
573 #if defined(GEN_TREES_H) || !defined(STDC)
574 extern uch _length_code[];
575 extern uch _dist_code[];
576 #else
577 extern const uch _length_code[];
578 extern const uch _dist_code[];
579 #endif
580
581 # define _tr_tally_lit(s, c, flush) \
582 { uch cc = (c); \
583 s->d_buf[s->last_lit] = 0; \
584 s->l_buf[s->last_lit++] = cc; \
585 s->dyn_ltree[cc].Freq++; \
586 flush = (s->last_lit == s->lit_bufsize-1); \
587 }
588 # define _tr_tally_dist(s, distance, length, flush) \
589 { uch len = (length); \
590 ush dist = (distance); \
591 s->d_buf[s->last_lit] = dist; \
592 s->l_buf[s->last_lit++] = len; \
593 dist--; \
594 s->dyn_ltree[_length_code[len]+LITERALS+1].Freq++; \
595 s->dyn_dtree[d_code(dist)].Freq++; \
596 flush = (s->last_lit == s->lit_bufsize-1); \
597 }
598 #else
599 # define _tr_tally_lit(s, c, flush) flush = _tr_tally(s, 0, c)
600 # define _tr_tally_dist(s, distance, length, flush) \
601 flush = _tr_tally(s, distance, length)
602 #endif
603
604 #endif
605 /* --- deflate.h */
606
607 /* +++ deflate.c */
608
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 1.13.4.2 2002/03/16 16:02:09 jdolecek 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) __P((deflate_state *s, int flush));
682 /* Compression function. Returns the block state after the call. */
683
684 local void fill_window __P((deflate_state *s));
685 local block_state deflate_stored __P((deflate_state *s, int flush));
686 local block_state deflate_fast __P((deflate_state *s, int flush));
687 local block_state deflate_slow __P((deflate_state *s, int flush));
688 local void lm_init __P((deflate_state *s));
689 local void putShortMSB __P((deflate_state *s, uInt b));
690 local void flush_pending __P((z_streamp strm));
691 local int read_buf __P((z_streamp strm, Bytef *buf, unsigned size));
692 #ifdef ASMV
693 void match_init __P((void)); /* asm code initialization */
694 uInt longest_match __P((deflate_state *s, IPos cur_match));
695 #else
696 local uInt longest_match __P((deflate_state *s, IPos cur_match));
697 #endif
698
699 #ifdef DEBUG_ZLIB
700 local void check_match __P((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 return Z_STREAM_ERROR;
915
916 s = (deflate_state *)strm->state;
917 if (s->status != INIT_STATE) return Z_STREAM_ERROR;
918
919 strm->adler = adler32(strm->adler, dictionary, dictLength);
920
921 if (length < MIN_MATCH) return Z_OK;
922 if (length > MAX_DIST(s)) {
923 length = MAX_DIST(s);
924 #ifndef USE_DICT_HEAD
925 dictionary += dictLength - length; /* use the tail of the dictionary */
926 #endif
927 }
928 zmemcpy(s->window, dictionary, length);
929 s->strstart = length;
930 s->block_start = (long)length;
931
932 /* Insert all strings in the hash table (except for the last two bytes).
933 * s->lookahead stays null, so s->ins_h will be recomputed at the next
934 * call of fill_window.
935 */
936 s->ins_h = s->window[0];
937 UPDATE_HASH(s, s->ins_h, s->window[1]);
938 for (n = 0; n <= length - MIN_MATCH; n++) {
939 INSERT_STRING(s, n, hash_head);
940 }
941 if (hash_head) hash_head = 0; /* to make compiler happy */
942 return Z_OK;
943 }
944
945 /* ========================================================================= */
946 int ZEXPORT deflateReset (strm)
947 z_streamp strm;
948 {
949 deflate_state *s;
950
951 if (strm == Z_NULL || strm->state == Z_NULL ||
952 strm->zalloc == Z_NULL || strm->zfree == Z_NULL) return Z_STREAM_ERROR;
953
954 strm->total_in = strm->total_out = 0;
955 strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */
956 strm->data_type = Z_UNKNOWN;
957
958 s = (deflate_state *)strm->state;
959 s->pending = 0;
960 s->pending_out = s->pending_buf;
961
962 if (s->noheader < 0) {
963 s->noheader = 0; /* was set to -1 by deflate(..., Z_FINISH); */
964 }
965 s->status = s->noheader ? BUSY_STATE : INIT_STATE;
966 strm->adler = 1;
967 s->last_flush = Z_NO_FLUSH;
968
969 _tr_init(s);
970 lm_init(s);
971
972 return Z_OK;
973 }
974
975 /* ========================================================================= */
976 int ZEXPORT deflateParams(strm, level, strategy)
977 z_streamp strm;
978 int level;
979 int strategy;
980 {
981 deflate_state *s;
982 compress_func func;
983 int err = Z_OK;
984
985 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
986 s = (deflate_state *)strm->state;
987
988 if (level == Z_DEFAULT_COMPRESSION) {
989 level = 6;
990 }
991 if (level < 0 || level > 9 || strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
992 return Z_STREAM_ERROR;
993 }
994 func = configuration_table[s->level].func;
995
996 if (func != configuration_table[level].func && strm->total_in != 0) {
997 /* Flush the last buffer: */
998 err = deflate(strm, Z_PARTIAL_FLUSH);
999 }
1000 if (s->level != level) {
1001 s->level = level;
1002 s->max_lazy_match = configuration_table[level].max_lazy;
1003 s->good_match = configuration_table[level].good_length;
1004 s->nice_match = configuration_table[level].nice_length;
1005 s->max_chain_length = configuration_table[level].max_chain;
1006 }
1007 s->strategy = strategy;
1008 return err;
1009 }
1010
1011 /* =========================================================================
1012 * Put a short in the pending buffer. The 16-bit value is put in MSB order.
1013 * IN assertion: the stream state is correct and there is enough room in
1014 * pending_buf.
1015 */
1016 local void putShortMSB (s, b)
1017 deflate_state *s;
1018 uInt b;
1019 {
1020 put_byte(s, (Byte)(b >> 8));
1021 put_byte(s, (Byte)(b & 0xff));
1022 }
1023
1024 /* =========================================================================
1025 * Flush as much pending output as possible. All deflate() output goes
1026 * through this function so some applications may wish to modify it
1027 * to avoid allocating a large strm->next_out buffer and copying into it.
1028 * (See also read_buf()).
1029 */
1030 local void flush_pending(strm)
1031 z_streamp strm;
1032 {
1033 deflate_state *s = (deflate_state *) strm->state;
1034 unsigned len = s->pending;
1035
1036 if (len > strm->avail_out) len = strm->avail_out;
1037 if (len == 0) return;
1038
1039 if (strm->next_out != Z_NULL) {
1040 zmemcpy(strm->next_out, s->pending_out, len);
1041 strm->next_out += len;
1042 }
1043 s->pending_out += len;
1044 strm->total_out += len;
1045 strm->avail_out -= len;
1046 s->pending -= len;
1047 if (s->pending == 0) {
1048 s->pending_out = s->pending_buf;
1049 }
1050 }
1051
1052 /* ========================================================================= */
1053 int ZEXPORT deflate (strm, flush)
1054 z_streamp strm;
1055 int flush;
1056 {
1057 int old_flush; /* value of flush param for previous deflate call */
1058 deflate_state *s;
1059
1060 if (strm == Z_NULL || strm->state == Z_NULL ||
1061 flush > Z_FINISH || flush < 0) {
1062 return Z_STREAM_ERROR;
1063 }
1064 s = (deflate_state *)strm->state;
1065
1066 if ((strm->next_in == Z_NULL && strm->avail_in != 0) ||
1067 (s->status == FINISH_STATE && flush != Z_FINISH)) {
1068 ERR_RETURN(strm, Z_STREAM_ERROR);
1069 }
1070 if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR);
1071
1072 s->strm = strm; /* just in case */
1073 old_flush = s->last_flush;
1074 s->last_flush = flush;
1075
1076 /* Write the zlib header */
1077 if (s->status == INIT_STATE) {
1078
1079 uInt header = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8;
1080 uInt level_flags = (s->level-1) >> 1;
1081
1082 if (level_flags > 3) level_flags = 3;
1083 header |= (level_flags << 6);
1084 if (s->strstart != 0) header |= PRESET_DICT;
1085 header += 31 - (header % 31);
1086
1087 s->status = BUSY_STATE;
1088 putShortMSB(s, header);
1089
1090 /* Save the adler32 of the preset dictionary: */
1091 if (s->strstart != 0) {
1092 putShortMSB(s, (uInt)(strm->adler >> 16));
1093 putShortMSB(s, (uInt)(strm->adler & 0xffff));
1094 }
1095 strm->adler = 1L;
1096 }
1097
1098 /* Flush as much pending output as possible */
1099 if (s->pending != 0) {
1100 flush_pending(strm);
1101 if (strm->avail_out == 0) {
1102 /* Since avail_out is 0, deflate will be called again with
1103 * more output space, but possibly with both pending and
1104 * avail_in equal to zero. There won't be anything to do,
1105 * but this is not an error situation so make sure we
1106 * return OK instead of BUF_ERROR at next call of deflate:
1107 */
1108 s->last_flush = -1;
1109 return Z_OK;
1110 }
1111
1112 /* Make sure there is something to do and avoid duplicate consecutive
1113 * flushes. For repeated and useless calls with Z_FINISH, we keep
1114 * returning Z_STREAM_END instead of Z_BUFF_ERROR.
1115 */
1116 } else if (strm->avail_in == 0 && flush <= old_flush &&
1117 flush != Z_FINISH) {
1118 ERR_RETURN(strm, Z_BUF_ERROR);
1119 }
1120
1121 /* User must not provide more input after the first FINISH: */
1122 if (s->status == FINISH_STATE && strm->avail_in != 0) {
1123 ERR_RETURN(strm, Z_BUF_ERROR);
1124 }
1125
1126 /* Start a new block or continue the current one.
1127 */
1128 if (strm->avail_in != 0 || s->lookahead != 0 ||
1129 (flush != Z_NO_FLUSH && s->status != FINISH_STATE)) {
1130 block_state bstate;
1131
1132 bstate = (*(configuration_table[s->level].func))(s, flush);
1133
1134 if (bstate == finish_started || bstate == finish_done) {
1135 s->status = FINISH_STATE;
1136 }
1137 if (bstate == need_more || bstate == finish_started) {
1138 if (strm->avail_out == 0) {
1139 s->last_flush = -1; /* avoid BUF_ERROR next call, see above */
1140 }
1141 return Z_OK;
1142 /* If flush != Z_NO_FLUSH && avail_out == 0, the next call
1143 * of deflate should use the same flush parameter to make sure
1144 * that the flush is complete. So we don't have to output an
1145 * empty block here, this will be done at next call. This also
1146 * ensures that for a very small output buffer, we emit at most
1147 * one empty block.
1148 */
1149 }
1150 if (bstate == block_done) {
1151 if (flush == Z_PARTIAL_FLUSH) {
1152 _tr_align(s);
1153 } else if (flush == Z_PACKET_FLUSH) {
1154 /* Output just the 3-bit `stored' block type value,
1155 but not a zero length. */
1156 _tr_stored_type_only(s);
1157 } else { /* FULL_FLUSH or SYNC_FLUSH */
1158 _tr_stored_block(s, (char*)0, 0L, 0);
1159 /* For a full flush, this empty block will be recognized
1160 * as a special marker by inflate_sync().
1161 */
1162 if (flush == Z_FULL_FLUSH) {
1163 CLEAR_HASH(s); /* forget history */
1164 }
1165 }
1166 flush_pending(strm);
1167 if (strm->avail_out == 0) {
1168 s->last_flush = -1; /* avoid BUF_ERROR at next call, see above */
1169 return Z_OK;
1170 }
1171 }
1172 }
1173 Assert(strm->avail_out > 0, "bug2");
1174
1175 if (flush != Z_FINISH) return Z_OK;
1176 if (s->noheader) return Z_STREAM_END;
1177
1178 /* Write the zlib trailer (adler32) */
1179 putShortMSB(s, (uInt)(strm->adler >> 16));
1180 putShortMSB(s, (uInt)(strm->adler & 0xffff));
1181 flush_pending(strm);
1182 /* If avail_out is zero, the application will call deflate again
1183 * to flush the rest.
1184 */
1185 s->noheader = -1; /* write the trailer only once! */
1186 return s->pending != 0 ? Z_OK : Z_STREAM_END;
1187 }
1188
1189 /* ========================================================================= */
1190 int ZEXPORT deflateEnd (strm)
1191 z_streamp strm;
1192 {
1193 int status;
1194 deflate_state *s;
1195
1196 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
1197 s = (deflate_state *) strm->state;
1198
1199 status = s->status;
1200 if (status != INIT_STATE && status != BUSY_STATE &&
1201 status != FINISH_STATE) {
1202 return Z_STREAM_ERROR;
1203 }
1204
1205 /* Deallocate in reverse order of allocations: */
1206 TRY_FREE(strm, s->pending_buf);
1207 TRY_FREE(strm, s->head);
1208 TRY_FREE(strm, s->prev);
1209 TRY_FREE(strm, s->window);
1210
1211 ZFREE(strm, s);
1212 strm->state = Z_NULL;
1213
1214 return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK;
1215 }
1216
1217 /* =========================================================================
1218 * Copy the source state to the destination state.
1219 * To simplify the source, this is not supported for 16-bit MSDOS (which
1220 * doesn't have enough memory anyway to duplicate compression states).
1221 */
1222 int ZEXPORT deflateCopy (dest, source)
1223 z_streamp dest;
1224 z_streamp source;
1225 {
1226 #ifdef MAXSEG_64K
1227 return Z_STREAM_ERROR;
1228 #else
1229 deflate_state *ds;
1230 deflate_state *ss;
1231 ushf *overlay;
1232
1233
1234 if (source == Z_NULL || dest == Z_NULL || source->state == Z_NULL) {
1235 return Z_STREAM_ERROR;
1236 }
1237
1238 ss = (deflate_state *)source->state;
1239
1240 *dest = *source;
1241
1242 ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state));
1243 if (ds == Z_NULL) return Z_MEM_ERROR;
1244 dest->state = (void *) ds;
1245 *ds = *ss;
1246 ds->strm = dest;
1247
1248 ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte));
1249 ds->prev = (Posf *) ZALLOC(dest, ds->w_size, sizeof(Pos));
1250 ds->head = (Posf *) ZALLOC(dest, ds->hash_size, sizeof(Pos));
1251 overlay = (ushf *) ZALLOC(dest, ds->lit_bufsize, sizeof(ush)+2);
1252 ds->pending_buf = (uchf *) overlay;
1253
1254 if (ds->window == Z_NULL || ds->prev == Z_NULL || ds->head == Z_NULL ||
1255 ds->pending_buf == Z_NULL) {
1256 deflateEnd (dest);
1257 return Z_MEM_ERROR;
1258 }
1259 /* following zmemcpy do not work for 16-bit MSDOS */
1260 zmemcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte));
1261 zmemcpy(ds->prev, ss->prev, ds->w_size * sizeof(Pos));
1262 zmemcpy(ds->head, ss->head, ds->hash_size * sizeof(Pos));
1263 zmemcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size);
1264
1265 ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf);
1266 ds->d_buf = overlay + ds->lit_bufsize/sizeof(ush);
1267 ds->l_buf = ds->pending_buf + (1+sizeof(ush))*ds->lit_bufsize;
1268
1269 ds->l_desc.dyn_tree = ds->dyn_ltree;
1270 ds->d_desc.dyn_tree = ds->dyn_dtree;
1271 ds->bl_desc.dyn_tree = ds->bl_tree;
1272
1273 return Z_OK;
1274 #endif
1275 }
1276
1277 /* ===========================================================================
1278 * Return the number of bytes of output which are immediately available
1279 * for output from the decompressor.
1280 */
1281 int deflateOutputPending (strm)
1282 z_streamp strm;
1283 {
1284 if (strm == Z_NULL || strm->state == Z_NULL) return 0;
1285
1286 return ((deflate_state *)(strm->state))->pending;
1287 }
1288
1289 /* ===========================================================================
1290 * Read a new buffer from the current input stream, update the adler32
1291 * and total number of bytes read. All deflate() input goes through
1292 * this function so some applications may wish to modify it to avoid
1293 * allocating a large strm->next_in buffer and copying from it.
1294 * (See also flush_pending()).
1295 */
1296 local int read_buf(strm, buf, size)
1297 z_streamp strm;
1298 Bytef *buf;
1299 unsigned size;
1300 {
1301 unsigned len = strm->avail_in;
1302
1303 if (len > size) len = size;
1304 if (len == 0) return 0;
1305
1306 strm->avail_in -= len;
1307
1308 if (!((deflate_state *)(strm->state))->noheader) {
1309 strm->adler = adler32(strm->adler, strm->next_in, len);
1310 }
1311 zmemcpy(buf, strm->next_in, len);
1312 strm->next_in += len;
1313 strm->total_in += len;
1314
1315 return (int)len;
1316 }
1317
1318 /* ===========================================================================
1319 * Initialize the "longest match" routines for a new zlib stream
1320 */
1321 local void lm_init (s)
1322 deflate_state *s;
1323 {
1324 s->window_size = (ulg)2L*s->w_size;
1325
1326 CLEAR_HASH(s);
1327
1328 /* Set the default configuration parameters:
1329 */
1330 s->max_lazy_match = configuration_table[s->level].max_lazy;
1331 s->good_match = configuration_table[s->level].good_length;
1332 s->nice_match = configuration_table[s->level].nice_length;
1333 s->max_chain_length = configuration_table[s->level].max_chain;
1334
1335 s->strstart = 0;
1336 s->block_start = 0L;
1337 s->lookahead = 0;
1338 s->match_length = s->prev_length = MIN_MATCH-1;
1339 s->match_available = 0;
1340 s->ins_h = 0;
1341 #ifdef ASMV
1342 match_init(); /* initialize the asm code */
1343 #endif
1344 }
1345
1346 /* ===========================================================================
1347 * Set match_start to the longest match starting at the given string and
1348 * return its length. Matches shorter or equal to prev_length are discarded,
1349 * in which case the result is equal to prev_length and match_start is
1350 * garbage.
1351 * IN assertions: cur_match is the head of the hash chain for the current
1352 * string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1
1353 * OUT assertion: the match length is not greater than s->lookahead.
1354 */
1355 #ifndef ASMV
1356 /* For 80x86 and 680x0, an optimized version will be provided in match.asm or
1357 * match.S. The code will be functionally equivalent.
1358 */
1359 #ifndef FASTEST
1360 local uInt longest_match(s, cur_match)
1361 deflate_state *s;
1362 IPos cur_match; /* current match */
1363 {
1364 unsigned chain_length = s->max_chain_length;/* max hash chain length */
1365 Bytef *scan = s->window + s->strstart; /* current string */
1366 Bytef *match; /* matched string */
1367 int len; /* length of current match */
1368 int best_len = s->prev_length; /* best match length so far */
1369 int nice_match = s->nice_match; /* stop if match long enough */
1370 IPos limit = s->strstart > (IPos)MAX_DIST(s) ?
1371 s->strstart - (IPos)MAX_DIST(s) : NIL;
1372 /* Stop when cur_match becomes <= limit. To simplify the code,
1373 * we prevent matches with the string of window index 0.
1374 */
1375 Posf *prev = s->prev;
1376 uInt wmask = s->w_mask;
1377
1378 #ifdef UNALIGNED_OK
1379 /* Compare two bytes at a time. Note: this is not always beneficial.
1380 * Try with and without -DUNALIGNED_OK to check.
1381 */
1382 Bytef *strend = s->window + s->strstart + MAX_MATCH - 1;
1383 ush scan_start = *(ushf*)scan;
1384 ush scan_end = *(ushf*)(scan+best_len-1);
1385 #else
1386 Bytef *strend = s->window + s->strstart + MAX_MATCH;
1387 Byte scan_end1 = scan[best_len-1];
1388 Byte scan_end = scan[best_len];
1389 #endif
1390
1391 /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
1392 * It is easy to get rid of this optimization if necessary.
1393 */
1394 Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");
1395
1396 /* Do not waste too much time if we already have a good match: */
1397 if (s->prev_length >= s->good_match) {
1398 chain_length >>= 2;
1399 }
1400 /* Do not look for matches beyond the end of the input. This is necessary
1401 * to make deflate deterministic.
1402 */
1403 if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;
1404
1405 Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
1406
1407 do {
1408 Assert(cur_match < s->strstart, "no future");
1409 match = s->window + cur_match;
1410
1411 /* Skip to next match if the match length cannot increase
1412 * or if the match length is less than 2:
1413 */
1414 #if (defined(UNALIGNED_OK) && MAX_MATCH == 258)
1415 /* This code assumes sizeof(unsigned short) == 2. Do not use
1416 * UNALIGNED_OK if your compiler uses a different size.
1417 */
1418 if (*(ushf*)(match+best_len-1) != scan_end ||
1419 *(ushf*)match != scan_start) continue;
1420
1421 /* It is not necessary to compare scan[2] and match[2] since they are
1422 * always equal when the other bytes match, given that the hash keys
1423 * are equal and that HASH_BITS >= 8. Compare 2 bytes at a time at
1424 * strstart+3, +5, ... up to strstart+257. We check for insufficient
1425 * lookahead only every 4th comparison; the 128th check will be made
1426 * at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is
1427 * necessary to put more guard bytes at the end of the window, or
1428 * to check more often for insufficient lookahead.
1429 */
1430 Assert(scan[2] == match[2], "scan[2]?");
1431 scan++, match++;
1432 do {
1433 } while (*(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1434 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1435 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1436 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1437 scan < strend);
1438 /* The funny "do {}" generates better code on most compilers */
1439
1440 /* Here, scan <= window+strstart+257 */
1441 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1442 if (*scan == *match) scan++;
1443
1444 len = (MAX_MATCH - 1) - (int)(strend-scan);
1445 scan = strend - (MAX_MATCH-1);
1446
1447 #else /* UNALIGNED_OK */
1448
1449 if (match[best_len] != scan_end ||
1450 match[best_len-1] != scan_end1 ||
1451 *match != *scan ||
1452 *++match != scan[1]) continue;
1453
1454 /* The check at best_len-1 can be removed because it will be made
1455 * again later. (This heuristic is not always a win.)
1456 * It is not necessary to compare scan[2] and match[2] since they
1457 * are always equal when the other bytes match, given that
1458 * the hash keys are equal and that HASH_BITS >= 8.
1459 */
1460 scan += 2, match++;
1461 Assert(*scan == *match, "match[2]?");
1462
1463 /* We check for insufficient lookahead only every 8th comparison;
1464 * the 256th check will be made at strstart+258.
1465 */
1466 do {
1467 } while (*++scan == *++match && *++scan == *++match &&
1468 *++scan == *++match && *++scan == *++match &&
1469 *++scan == *++match && *++scan == *++match &&
1470 *++scan == *++match && *++scan == *++match &&
1471 scan < strend);
1472
1473 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1474
1475 len = MAX_MATCH - (int)(strend - scan);
1476 scan = strend - MAX_MATCH;
1477
1478 #endif /* UNALIGNED_OK */
1479
1480 if (len > best_len) {
1481 s->match_start = cur_match;
1482 best_len = len;
1483 if (len >= nice_match) break;
1484 #ifdef UNALIGNED_OK
1485 scan_end = *(ushf*)(scan+best_len-1);
1486 #else
1487 scan_end1 = scan[best_len-1];
1488 scan_end = scan[best_len];
1489 #endif
1490 }
1491 } while ((cur_match = prev[cur_match & wmask]) > limit
1492 && --chain_length != 0);
1493
1494 if ((uInt)best_len <= s->lookahead) return (uInt)best_len;
1495 return s->lookahead;
1496 }
1497
1498 #else /* FASTEST */
1499 /* ---------------------------------------------------------------------------
1500 * Optimized version for level == 1 only
1501 */
1502 local uInt longest_match(s, cur_match)
1503 deflate_state *s;
1504 IPos cur_match; /* current match */
1505 {
1506 register Bytef *scan = s->window + s->strstart; /* current string */
1507 register Bytef *match; /* matched string */
1508 register int len; /* length of current match */
1509 register Bytef *strend = s->window + s->strstart + MAX_MATCH;
1510
1511 /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
1512 * It is easy to get rid of this optimization if necessary.
1513 */
1514 Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");
1515
1516 Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
1517
1518 Assert(cur_match < s->strstart, "no future");
1519
1520 match = s->window + cur_match;
1521
1522 /* Return failure if the match length is less than 2:
1523 */
1524 if (match[0] != scan[0] || match[1] != scan[1]) return MIN_MATCH-1;
1525
1526 /* The check at best_len-1 can be removed because it will be made
1527 * again later. (This heuristic is not always a win.)
1528 * It is not necessary to compare scan[2] and match[2] since they
1529 * are always equal when the other bytes match, given that
1530 * the hash keys are equal and that HASH_BITS >= 8.
1531 */
1532 scan += 2, match += 2;
1533 Assert(*scan == *match, "match[2]?");
1534
1535 /* We check for insufficient lookahead only every 8th comparison;
1536 * the 256th check will be made at strstart+258.
1537 */
1538 do {
1539 } while (*++scan == *++match && *++scan == *++match &&
1540 *++scan == *++match && *++scan == *++match &&
1541 *++scan == *++match && *++scan == *++match &&
1542 *++scan == *++match && *++scan == *++match &&
1543 scan < strend);
1544
1545 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1546
1547 len = MAX_MATCH - (int)(strend - scan);
1548
1549 if (len < MIN_MATCH) return MIN_MATCH - 1;
1550
1551 s->match_start = cur_match;
1552 return len <= s->lookahead ? len : s->lookahead;
1553 }
1554 #endif /* FASTEST */
1555 #endif /* ASMV */
1556
1557 #ifdef DEBUG_ZLIB
1558 /* ===========================================================================
1559 * Check that the match at match_start is indeed a match.
1560 */
1561 local void check_match(s, start, match, length)
1562 deflate_state *s;
1563 IPos start, match;
1564 int length;
1565 {
1566 /* check that the match is indeed a match */
1567 if (zmemcmp(s->window + match,
1568 s->window + start, length) != EQUAL) {
1569 fprintf(stderr, " start %u, match %u, length %d\n",
1570 start, match, length);
1571 do {
1572 fprintf(stderr, "%c%c", s->window[match++], s->window[start++]);
1573 } while (--length != 0);
1574 z_error("invalid match");
1575 }
1576 if (z_verbose > 1) {
1577 fprintf(stderr,"\\[%d,%d]", start-match, length);
1578 do { putc(s->window[start++], stderr); } while (--length != 0);
1579 }
1580 }
1581 #else
1582 # define check_match(s, start, match, length)
1583 #endif
1584
1585 /* ===========================================================================
1586 * Fill the window when the lookahead becomes insufficient.
1587 * Updates strstart and lookahead.
1588 *
1589 * IN assertion: lookahead < MIN_LOOKAHEAD
1590 * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD
1591 * At least one byte has been read, or avail_in == 0; reads are
1592 * performed for at least two bytes (required for the zip translate_eol
1593 * option -- not supported here).
1594 */
1595 local void fill_window(s)
1596 deflate_state *s;
1597 {
1598 unsigned n, m;
1599 Posf *p;
1600 unsigned more; /* Amount of free space at the end of the window. */
1601 uInt wsize = s->w_size;
1602
1603 do {
1604 more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart);
1605
1606 /* Deal with !@#$% 64K limit: */
1607 if (more == 0 && s->strstart == 0 && s->lookahead == 0) {
1608 more = wsize;
1609
1610 } else if (more == (unsigned)(-1)) {
1611 /* Very unlikely, but possible on 16 bit machine if strstart == 0
1612 * and lookahead == 1 (input done one byte at time)
1613 */
1614 more--;
1615
1616 /* If the window is almost full and there is insufficient lookahead,
1617 * move the upper half to the lower one to make room in the upper half.
1618 */
1619 } else if (s->strstart >= wsize+MAX_DIST(s)) {
1620
1621 zmemcpy(s->window, s->window+wsize, (unsigned)wsize);
1622 s->match_start -= wsize;
1623 s->strstart -= wsize; /* we now have strstart >= MAX_DIST */
1624 s->block_start -= (long) wsize;
1625
1626 /* Slide the hash table (could be avoided with 32 bit values
1627 at the expense of memory usage). We slide even when level == 0
1628 to keep the hash table consistent if we switch back to level > 0
1629 later. (Using level 0 permanently is not an optimal usage of
1630 zlib, so we don't care about this pathological case.)
1631 */
1632 n = s->hash_size;
1633 p = &s->head[n];
1634 do {
1635 m = *--p;
1636 *p = (Pos)(m >= wsize ? m-wsize : NIL);
1637 } while (--n);
1638
1639 n = wsize;
1640 #ifndef FASTEST
1641 p = &s->prev[n];
1642 do {
1643 m = *--p;
1644 *p = (Pos)(m >= wsize ? m-wsize : NIL);
1645 /* If n is not on any hash chain, prev[n] is garbage but
1646 * its value will never be used.
1647 */
1648 } while (--n);
1649 #endif
1650 more += wsize;
1651 }
1652 if (s->strm->avail_in == 0) return;
1653
1654 /* If there was no sliding:
1655 * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 &&
1656 * more == window_size - lookahead - strstart
1657 * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1)
1658 * => more >= window_size - 2*WSIZE + 2
1659 * In the BIG_MEM or MMAP case (not yet supported),
1660 * window_size == input_size + MIN_LOOKAHEAD &&
1661 * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD.
1662 * Otherwise, window_size == 2*WSIZE so more >= 2.
1663 * If there was sliding, more >= WSIZE. So in all cases, more >= 2.
1664 */
1665 Assert(more >= 2, "more < 2");
1666
1667 n = read_buf(s->strm, s->window + s->strstart + s->lookahead, more);
1668 s->lookahead += n;
1669
1670 /* Initialize the hash value now that we have some input: */
1671 if (s->lookahead >= MIN_MATCH) {
1672 s->ins_h = s->window[s->strstart];
1673 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
1674 #if MIN_MATCH != 3
1675 Call UPDATE_HASH() MIN_MATCH-3 more times
1676 #endif
1677 }
1678 /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage,
1679 * but this is not important since only literal bytes will be emitted.
1680 */
1681
1682 } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0);
1683 }
1684
1685 /* ===========================================================================
1686 * Flush the current block, with given end-of-file flag.
1687 * IN assertion: strstart is set to the end of the current match.
1688 */
1689 #define FLUSH_BLOCK_ONLY(s, eof) { \
1690 _tr_flush_block(s, (s->block_start >= 0L ? \
1691 (charf *)&s->window[(unsigned)s->block_start] : \
1692 (charf *)Z_NULL), \
1693 (ulg)((long)s->strstart - s->block_start), \
1694 (eof)); \
1695 s->block_start = s->strstart; \
1696 flush_pending(s->strm); \
1697 Tracev((stderr,"[FLUSH]")); \
1698 }
1699
1700 /* Same but force premature exit if necessary. */
1701 #define FLUSH_BLOCK(s, eof) { \
1702 FLUSH_BLOCK_ONLY(s, eof); \
1703 if (s->strm->avail_out == 0) return (eof) ? finish_started : need_more; \
1704 }
1705
1706 /* ===========================================================================
1707 * Copy without compression as much as possible from the input stream, return
1708 * the current block state.
1709 * This function does not insert new strings in the dictionary since
1710 * uncompressible data is probably not useful. This function is used
1711 * only for the level=0 compression option.
1712 * NOTE: this function should be optimized to avoid extra copying from
1713 * window to pending_buf.
1714 */
1715 local block_state deflate_stored(s, flush)
1716 deflate_state *s;
1717 int flush;
1718 {
1719 /* Stored blocks are limited to 0xffff bytes, pending_buf is limited
1720 * to pending_buf_size, and each stored block has a 5 byte header:
1721 */
1722 ulg max_block_size = 0xffff;
1723 ulg max_start;
1724
1725 if (max_block_size > s->pending_buf_size - 5) {
1726 max_block_size = s->pending_buf_size - 5;
1727 }
1728
1729 /* Copy as much as possible from input to output: */
1730 for (;;) {
1731 /* Fill the window as much as possible: */
1732 if (s->lookahead <= 1) {
1733
1734 Assert(s->strstart < s->w_size+MAX_DIST(s) ||
1735 s->block_start >= (long)s->w_size, "slide too late");
1736
1737 fill_window(s);
1738 if (s->lookahead == 0 && flush == Z_NO_FLUSH) return need_more;
1739
1740 if (s->lookahead == 0) break; /* flush the current block */
1741 }
1742 Assert(s->block_start >= 0L, "block gone");
1743
1744 s->strstart += s->lookahead;
1745 s->lookahead = 0;
1746
1747 /* Emit a stored block if pending_buf will be full: */
1748 max_start = s->block_start + max_block_size;
1749 if (s->strstart == 0 || (ulg)s->strstart >= max_start) {
1750 /* strstart == 0 is possible when wraparound on 16-bit machine */
1751 s->lookahead = (uInt)(s->strstart - max_start);
1752 s->strstart = (uInt)max_start;
1753 FLUSH_BLOCK(s, 0);
1754 }
1755 /* Flush if we may have to slide, otherwise block_start may become
1756 * negative and the data will be gone:
1757 */
1758 if (s->strstart - (uInt)s->block_start >= MAX_DIST(s)) {
1759 FLUSH_BLOCK(s, 0);
1760 }
1761 }
1762 FLUSH_BLOCK(s, flush == Z_FINISH);
1763 return flush == Z_FINISH ? finish_done : block_done;
1764 }
1765
1766 /* ===========================================================================
1767 * Compress as much as possible from the input stream, return the current
1768 * block state.
1769 * This function does not perform lazy evaluation of matches and inserts
1770 * new strings in the dictionary only for unmatched strings or for short
1771 * matches. It is used only for the fast compression options.
1772 */
1773 local block_state deflate_fast(s, flush)
1774 deflate_state *s;
1775 int flush;
1776 {
1777 IPos hash_head = NIL; /* head of the hash chain */
1778 int bflush; /* set if current block must be flushed */
1779
1780 for (;;) {
1781 /* Make sure that we always have enough lookahead, except
1782 * at the end of the input file. We need MAX_MATCH bytes
1783 * for the next match, plus MIN_MATCH bytes to insert the
1784 * string following the next match.
1785 */
1786 if (s->lookahead < MIN_LOOKAHEAD) {
1787 fill_window(s);
1788 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
1789 return need_more;
1790 }
1791 if (s->lookahead == 0) break; /* flush the current block */
1792 }
1793
1794 /* Insert the string window[strstart .. strstart+2] in the
1795 * dictionary, and set hash_head to the head of the hash chain:
1796 */
1797 if (s->lookahead >= MIN_MATCH) {
1798 INSERT_STRING(s, s->strstart, hash_head);
1799 }
1800
1801 /* Find the longest match, discarding those <= prev_length.
1802 * At this point we have always match_length < MIN_MATCH
1803 */
1804 if (hash_head != NIL && s->strstart - hash_head <= MAX_DIST(s)) {
1805 /* To simplify the code, we prevent matches with the string
1806 * of window index 0 (in particular we have to avoid a match
1807 * of the string with itself at the start of the input file).
1808 */
1809 if (s->strategy != Z_HUFFMAN_ONLY) {
1810 s->match_length = longest_match (s, hash_head);
1811 }
1812 /* longest_match() sets match_start */
1813 }
1814 if (s->match_length >= MIN_MATCH) {
1815 check_match(s, s->strstart, s->match_start, s->match_length);
1816
1817 _tr_tally_dist(s, s->strstart - s->match_start,
1818 s->match_length - MIN_MATCH, bflush);
1819
1820 s->lookahead -= s->match_length;
1821
1822 /* Insert new strings in the hash table only if the match length
1823 * is not too large. This saves time but degrades compression.
1824 */
1825 #ifndef FASTEST
1826 if (s->match_length <= s->max_insert_length &&
1827 s->lookahead >= MIN_MATCH) {
1828 s->match_length--; /* string at strstart already in hash table */
1829 do {
1830 s->strstart++;
1831 INSERT_STRING(s, s->strstart, hash_head);
1832 /* strstart never exceeds WSIZE-MAX_MATCH, so there are
1833 * always MIN_MATCH bytes ahead.
1834 */
1835 } while (--s->match_length != 0);
1836 s->strstart++;
1837 } else
1838 #endif
1839 {
1840 s->strstart += s->match_length;
1841 s->match_length = 0;
1842 s->ins_h = s->window[s->strstart];
1843 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
1844 #if MIN_MATCH != 3
1845 Call UPDATE_HASH() MIN_MATCH-3 more times
1846 #endif
1847 /* If lookahead < MIN_MATCH, ins_h is garbage, but it does not
1848 * matter since it will be recomputed at next deflate call.
1849 */
1850 }
1851 } else {
1852 /* No match, output a literal byte */
1853 Tracevv((stderr,"%c", s->window[s->strstart]));
1854 _tr_tally_lit (s, s->window[s->strstart], bflush);
1855 s->lookahead--;
1856 s->strstart++;
1857 }
1858 if (bflush) FLUSH_BLOCK(s, 0);
1859 }
1860 FLUSH_BLOCK(s, flush == Z_FINISH);
1861 return flush == Z_FINISH ? finish_done : block_done;
1862 }
1863
1864 /* ===========================================================================
1865 * Same as above, but achieves better compression. We use a lazy
1866 * evaluation for matches: a match is finally adopted only if there is
1867 * no better match at the next window position.
1868 */
1869 local block_state deflate_slow(s, flush)
1870 deflate_state *s;
1871 int flush;
1872 {
1873 IPos hash_head = NIL; /* head of hash chain */
1874 int bflush; /* set if current block must be flushed */
1875
1876 /* Process the input block. */
1877 for (;;) {
1878 /* Make sure that we always have enough lookahead, except
1879 * at the end of the input file. We need MAX_MATCH bytes
1880 * for the next match, plus MIN_MATCH bytes to insert the
1881 * string following the next match.
1882 */
1883 if (s->lookahead < MIN_LOOKAHEAD) {
1884 fill_window(s);
1885 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
1886 return need_more;
1887 }
1888 if (s->lookahead == 0) break; /* flush the current block */
1889 }
1890
1891 /* Insert the string window[strstart .. strstart+2] in the
1892 * dictionary, and set hash_head to the head of the hash chain:
1893 */
1894 if (s->lookahead >= MIN_MATCH) {
1895 INSERT_STRING(s, s->strstart, hash_head);
1896 }
1897
1898 /* Find the longest match, discarding those <= prev_length.
1899 */
1900 s->prev_length = s->match_length, s->prev_match = s->match_start;
1901 s->match_length = MIN_MATCH-1;
1902
1903 if (hash_head != NIL && s->prev_length < s->max_lazy_match &&
1904 s->strstart - hash_head <= MAX_DIST(s)) {
1905 /* To simplify the code, we prevent matches with the string
1906 * of window index 0 (in particular we have to avoid a match
1907 * of the string with itself at the start of the input file).
1908 */
1909 if (s->strategy != Z_HUFFMAN_ONLY) {
1910 s->match_length = longest_match (s, hash_head);
1911 }
1912 /* longest_match() sets match_start */
1913
1914 if (s->match_length <= 5 && (s->strategy == Z_FILTERED ||
1915 (s->match_length == MIN_MATCH &&
1916 s->strstart - s->match_start > TOO_FAR))) {
1917
1918 /* If prev_match is also MIN_MATCH, match_start is garbage
1919 * but we will ignore the current match anyway.
1920 */
1921 s->match_length = MIN_MATCH-1;
1922 }
1923 }
1924 /* If there was a match at the previous step and the current
1925 * match is not better, output the previous match:
1926 */
1927 if (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) {
1928 uInt max_insert = s->strstart + s->lookahead - MIN_MATCH;
1929 /* Do not insert strings in hash table beyond this. */
1930
1931 check_match(s, s->strstart-1, s->prev_match, s->prev_length);
1932
1933 _tr_tally_dist(s, s->strstart -1 - s->prev_match,
1934 s->prev_length - MIN_MATCH, bflush);
1935
1936 /* Insert in hash table all strings up to the end of the match.
1937 * strstart-1 and strstart are already inserted. If there is not
1938 * enough lookahead, the last two strings are not inserted in
1939 * the hash table.
1940 */
1941 s->lookahead -= s->prev_length-1;
1942 s->prev_length -= 2;
1943 do {
1944 if (++s->strstart <= max_insert) {
1945 INSERT_STRING(s, s->strstart, hash_head);
1946 }
1947 } while (--s->prev_length != 0);
1948 s->match_available = 0;
1949 s->match_length = MIN_MATCH-1;
1950 s->strstart++;
1951
1952 if (bflush) FLUSH_BLOCK(s, 0);
1953
1954 } else if (s->match_available) {
1955 /* If there was no match at the previous position, output a
1956 * single literal. If there was a match but the current match
1957 * is longer, truncate the previous match to a single literal.
1958 */
1959 Tracevv((stderr,"%c", s->window[s->strstart-1]));
1960 _tr_tally_lit(s, s->window[s->strstart-1], bflush);
1961 if (bflush) {
1962 FLUSH_BLOCK_ONLY(s, 0);
1963 }
1964 s->strstart++;
1965 s->lookahead--;
1966 if (s->strm->avail_out == 0) return need_more;
1967 } else {
1968 /* There is no previous match to compare with, wait for
1969 * the next step to decide.
1970 */
1971 s->match_available = 1;
1972 s->strstart++;
1973 s->lookahead--;
1974 }
1975 }
1976 Assert (flush != Z_NO_FLUSH, "no flush?");
1977 if (s->match_available) {
1978 Tracevv((stderr,"%c", s->window[s->strstart-1]));
1979 _tr_tally_lit(s, s->window[s->strstart-1], bflush);
1980 s->match_available = 0;
1981 }
1982 FLUSH_BLOCK(s, flush == Z_FINISH);
1983 return flush == Z_FINISH ? finish_done : block_done;
1984 }
1985 /* --- deflate.c */
1986
1987 /* +++ trees.c */
1988
1989 /* trees.c -- output deflated data using Huffman coding
1990 * Copyright (C) 1995-2002 Jean-loup Gailly
1991 * For conditions of distribution and use, see copyright notice in zlib.h
1992 */
1993
1994 /*
1995 * ALGORITHM
1996 *
1997 * The "deflation" process uses several Huffman trees. The more
1998 * common source values are represented by shorter bit sequences.
1999 *
2000 * Each code tree is stored in a compressed form which is itself
2001 * a Huffman encoding of the lengths of all the code strings (in
2002 * ascending order by source values). The actual code strings are
2003 * reconstructed from the lengths in the inflate process, as described
2004 * in the deflate specification.
2005 *
2006 * REFERENCES
2007 *
2008 * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification".
2009 * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc
2010 *
2011 * Storer, James A.
2012 * Data Compression: Methods and Theory, pp. 49-50.
2013 * Computer Science Press, 1988. ISBN 0-7167-8156-5.
2014 *
2015 * Sedgewick, R.
2016 * Algorithms, p290.
2017 * Addison-Wesley, 1983. ISBN 0-201-06672-6.
2018 */
2019
2020 /* @(#) $Id: zlib.c,v 1.13.4.2 2002/03/16 16:02:09 jdolecek Exp $ */
2021
2022 /* #define GEN_TREES_H */
2023
2024 /* #include "deflate.h" */
2025
2026 #ifdef DEBUG_ZLIB
2027 # include <ctype.h>
2028 #endif
2029
2030 /* ===========================================================================
2031 * Constants
2032 */
2033
2034 #define MAX_BL_BITS 7
2035 /* Bit length codes must not exceed MAX_BL_BITS bits */
2036
2037 #define END_BLOCK 256
2038 /* end of block literal code */
2039
2040 #define REP_3_6 16
2041 /* repeat previous bit length 3-6 times (2 bits of repeat count) */
2042
2043 #define REPZ_3_10 17
2044 /* repeat a zero length 3-10 times (3 bits of repeat count) */
2045
2046 #define REPZ_11_138 18
2047 /* repeat a zero length 11-138 times (7 bits of repeat count) */
2048
2049 local const int extra_lbits[LENGTH_CODES] /* extra bits for each length code */
2050 = {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};
2051
2052 local const int extra_dbits[D_CODES] /* extra bits for each distance code */
2053 = {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};
2054
2055 local const int extra_blbits[BL_CODES]/* extra bits for each bit length code */
2056 = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7};
2057
2058 local const uch bl_order[BL_CODES]
2059 = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15};
2060 /* The lengths of the bit length codes are sent in order of decreasing
2061 * probability, to avoid transmitting the lengths for unused bit length codes.
2062 */
2063
2064 #define Buf_size (8 * 2*sizeof(char))
2065 /* Number of bits used within bi_buf. (bi_buf might be implemented on
2066 * more than 16 bits on some systems.)
2067 */
2068
2069 /* ===========================================================================
2070 * Local data. These are initialized only once.
2071 */
2072
2073 #define DIST_CODE_LEN 512 /* see definition of array dist_code below */
2074
2075 #if defined(GEN_TREES_H) || !defined(STDC)
2076 /* non ANSI compilers may not accept trees.h */
2077
2078 local ct_data static_ltree[L_CODES+2];
2079 /* The static literal tree. Since the bit lengths are imposed, there is no
2080 * need for the L_CODES extra codes used during heap construction. However
2081 * The codes 286 and 287 are needed to build a canonical tree (see _tr_init
2082 * below).
2083 */
2084
2085 local ct_data static_dtree[D_CODES];
2086 /* The static distance tree. (Actually a trivial tree since all codes use
2087 * 5 bits.)
2088 */
2089
2090 uch _dist_code[DIST_CODE_LEN];
2091 /* Distance codes. The first 256 values correspond to the distances
2092 * 3 .. 258, the last 256 values correspond to the top 8 bits of
2093 * the 15 bit distances.
2094 */
2095
2096 uch _length_code[MAX_MATCH-MIN_MATCH+1];
2097 /* length code for each normalized match length (0 == MIN_MATCH) */
2098
2099 local int base_length[LENGTH_CODES];
2100 /* First normalized length for each code (0 = MIN_MATCH) */
2101
2102 local int base_dist[D_CODES];
2103 /* First normalized distance for each code (0 = distance of 1) */
2104
2105 #else
2106 /* +++ trees.h */
2107
2108 /* header created automatically with -DGEN_TREES_H */
2109
2110 local const ct_data static_ltree[L_CODES+2] = {
2111 {{ 12},{ 8}}, {{140},{ 8}}, {{ 76},{ 8}}, {{204},{ 8}}, {{ 44},{ 8}},
2112 {{172},{ 8}}, {{108},{ 8}}, {{236},{ 8}}, {{ 28},{ 8}}, {{156},{ 8}},
2113 {{ 92},{ 8}}, {{220},{ 8}}, {{ 60},{ 8}}, {{188},{ 8}}, {{124},{ 8}},
2114 {{252},{ 8}}, {{ 2},{ 8}}, {{130},{ 8}}, {{ 66},{ 8}}, {{194},{ 8}},
2115 {{ 34},{ 8}}, {{162},{ 8}}, {{ 98},{ 8}}, {{226},{ 8}}, {{ 18},{ 8}},
2116 {{146},{ 8}}, {{ 82},{ 8}}, {{210},{ 8}}, {{ 50},{ 8}}, {{178},{ 8}},
2117 {{114},{ 8}}, {{242},{ 8}}, {{ 10},{ 8}}, {{138},{ 8}}, {{ 74},{ 8}},
2118 {{202},{ 8}}, {{ 42},{ 8}}, {{170},{ 8}}, {{106},{ 8}}, {{234},{ 8}},
2119 {{ 26},{ 8}}, {{154},{ 8}}, {{ 90},{ 8}}, {{218},{ 8}}, {{ 58},{ 8}},
2120 {{186},{ 8}}, {{122},{ 8}}, {{250},{ 8}}, {{ 6},{ 8}}, {{134},{ 8}},
2121 {{ 70},{ 8}}, {{198},{ 8}}, {{ 38},{ 8}}, {{166},{ 8}}, {{102},{ 8}},
2122 {{230},{ 8}}, {{ 22},{ 8}}, {{150},{ 8}}, {{ 86},{ 8}}, {{214},{ 8}},
2123 {{ 54},{ 8}}, {{182},{ 8}}, {{118},{ 8}}, {{246},{ 8}}, {{ 14},{ 8}},
2124 {{142},{ 8}}, {{ 78},{ 8}}, {{206},{ 8}}, {{ 46},{ 8}}, {{174},{ 8}},
2125 {{110},{ 8}}, {{238},{ 8}}, {{ 30},{ 8}}, {{158},{ 8}}, {{ 94},{ 8}},
2126 {{222},{ 8}}, {{ 62},{ 8}}, {{190},{ 8}}, {{126},{ 8}}, {{254},{ 8}},
2127 {{ 1},{ 8}}, {{129},{ 8}}, {{ 65},{ 8}}, {{193},{ 8}}, {{ 33},{ 8}},
2128 {{161},{ 8}}, {{ 97},{ 8}}, {{225},{ 8}}, {{ 17},{ 8}}, {{145},{ 8}},
2129 {{ 81},{ 8}}, {{209},{ 8}}, {{ 49},{ 8}}, {{177},{ 8}}, {{113},{ 8}},
2130 {{241},{ 8}}, {{ 9},{ 8}}, {{137},{ 8}}, {{ 73},{ 8}}, {{201},{ 8}},
2131 {{ 41},{ 8}}, {{169},{ 8}}, {{105},{ 8}}, {{233},{ 8}}, {{ 25},{ 8}},
2132 {{153},{ 8}}, {{ 89},{ 8}}, {{217},{ 8}}, {{ 57},{ 8}}, {{185},{ 8}},
2133 {{121},{ 8}}, {{249},{ 8}}, {{ 5},{ 8}}, {{133},{ 8}}, {{ 69},{ 8}},
2134 {{197},{ 8}}, {{ 37},{ 8}}, {{165},{ 8}}, {{101},{ 8}}, {{229},{ 8}},
2135 {{ 21},{ 8}}, {{149},{ 8}}, {{ 85},{ 8}}, {{213},{ 8}}, {{ 53},{ 8}},
2136 {{181},{ 8}}, {{117},{ 8}}, {{245},{ 8}}, {{ 13},{ 8}}, {{141},{ 8}},
2137 {{ 77},{ 8}}, {{205},{ 8}}, {{ 45},{ 8}}, {{173},{ 8}}, {{109},{ 8}},
2138 {{237},{ 8}}, {{ 29},{ 8}}, {{157},{ 8}}, {{ 93},{ 8}}, {{221},{ 8}},
2139 {{ 61},{ 8}}, {{189},{ 8}}, {{125},{ 8}}, {{253},{ 8}}, {{ 19},{ 9}},
2140 {{275},{ 9}}, {{147},{ 9}}, {{403},{ 9}}, {{ 83},{ 9}}, {{339},{ 9}},
2141 {{211},{ 9}}, {{467},{ 9}}, {{ 51},{ 9}}, {{307},{ 9}}, {{179},{ 9}},
2142 {{435},{ 9}}, {{115},{ 9}}, {{371},{ 9}}, {{243},{ 9}}, {{499},{ 9}},
2143 {{ 11},{ 9}}, {{267},{ 9}}, {{139},{ 9}}, {{395},{ 9}}, {{ 75},{ 9}},
2144 {{331},{ 9}}, {{203},{ 9}}, {{459},{ 9}}, {{ 43},{ 9}}, {{299},{ 9}},
2145 {{171},{ 9}}, {{427},{ 9}}, {{107},{ 9}}, {{363},{ 9}}, {{235},{ 9}},
2146 {{491},{ 9}}, {{ 27},{ 9}}, {{283},{ 9}}, {{155},{ 9}}, {{411},{ 9}},
2147 {{ 91},{ 9}}, {{347},{ 9}}, {{219},{ 9}}, {{475},{ 9}}, {{ 59},{ 9}},
2148 {{315},{ 9}}, {{187},{ 9}}, {{443},{ 9}}, {{123},{ 9}}, {{379},{ 9}},
2149 {{251},{ 9}}, {{507},{ 9}}, {{ 7},{ 9}}, {{263},{ 9}}, {{135},{ 9}},
2150 {{391},{ 9}}, {{ 71},{ 9}}, {{327},{ 9}}, {{199},{ 9}}, {{455},{ 9}},
2151 {{ 39},{ 9}}, {{295},{ 9}}, {{167},{ 9}}, {{423},{ 9}}, {{103},{ 9}},
2152 {{359},{ 9}}, {{231},{ 9}}, {{487},{ 9}}, {{ 23},{ 9}}, {{279},{ 9}},
2153 {{151},{ 9}}, {{407},{ 9}}, {{ 87},{ 9}}, {{343},{ 9}}, {{215},{ 9}},
2154 {{471},{ 9}}, {{ 55},{ 9}}, {{311},{ 9}}, {{183},{ 9}}, {{439},{ 9}},
2155 {{119},{ 9}}, {{375},{ 9}}, {{247},{ 9}}, {{503},{ 9}}, {{ 15},{ 9}},
2156 {{271},{ 9}}, {{143},{ 9}}, {{399},{ 9}}, {{ 79},{ 9}}, {{335},{ 9}},
2157 {{207},{ 9}}, {{463},{ 9}}, {{ 47},{ 9}}, {{303},{ 9}}, {{175},{ 9}},
2158 {{431},{ 9}}, {{111},{ 9}}, {{367},{ 9}}, {{239},{ 9}}, {{495},{ 9}},
2159 {{ 31},{ 9}}, {{287},{ 9}}, {{159},{ 9}}, {{415},{ 9}}, {{ 95},{ 9}},
2160 {{351},{ 9}}, {{223},{ 9}}, {{479},{ 9}}, {{ 63},{ 9}}, {{319},{ 9}},
2161 {{191},{ 9}}, {{447},{ 9}}, {{127},{ 9}}, {{383},{ 9}}, {{255},{ 9}},
2162 {{511},{ 9}}, {{ 0},{ 7}}, {{ 64},{ 7}}, {{ 32},{ 7}}, {{ 96},{ 7}},
2163 {{ 16},{ 7}}, {{ 80},{ 7}}, {{ 48},{ 7}}, {{112},{ 7}}, {{ 8},{ 7}},
2164 {{ 72},{ 7}}, {{ 40},{ 7}}, {{104},{ 7}}, {{ 24},{ 7}}, {{ 88},{ 7}},
2165 {{ 56},{ 7}}, {{120},{ 7}}, {{ 4},{ 7}}, {{ 68},{ 7}}, {{ 36},{ 7}},
2166 {{100},{ 7}}, {{ 20},{ 7}}, {{ 84},{ 7}}, {{ 52},{ 7}}, {{116},{ 7}},
2167 {{ 3},{ 8}}, {{131},{ 8}}, {{ 67},{ 8}}, {{195},{ 8}}, {{ 35},{ 8}},
2168 {{163},{ 8}}, {{ 99},{ 8}}, {{227},{ 8}}
2169 };
2170
2171 local const ct_data static_dtree[D_CODES] = {
2172 {{ 0},{ 5}}, {{16},{ 5}}, {{ 8},{ 5}}, {{24},{ 5}}, {{ 4},{ 5}},
2173 {{20},{ 5}}, {{12},{ 5}}, {{28},{ 5}}, {{ 2},{ 5}}, {{18},{ 5}},
2174 {{10},{ 5}}, {{26},{ 5}}, {{ 6},{ 5}}, {{22},{ 5}}, {{14},{ 5}},
2175 {{30},{ 5}}, {{ 1},{ 5}}, {{17},{ 5}}, {{ 9},{ 5}}, {{25},{ 5}},
2176 {{ 5},{ 5}}, {{21},{ 5}}, {{13},{ 5}}, {{29},{ 5}}, {{ 3},{ 5}},
2177 {{19},{ 5}}, {{11},{ 5}}, {{27},{ 5}}, {{ 7},{ 5}}, {{23},{ 5}}
2178 };
2179
2180 const uch _dist_code[DIST_CODE_LEN] = {
2181 0, 1, 2, 3, 4, 4, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8, 8,
2182 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 10,
2183 10, 10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11,
2184 11, 11, 11, 11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
2185 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 13, 13, 13, 13,
2186 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13,
2187 13, 13, 13, 13, 13, 13, 13, 13, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
2188 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
2189 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
2190 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 15, 15, 15, 15, 15, 15, 15, 15,
2191 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
2192 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
2193 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 0, 0, 16, 17,
2194 18, 18, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 22, 22, 22, 22, 22, 22, 22, 22,
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, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
2197 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
2198 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 27, 27, 27, 27, 27, 27, 27, 27,
2199 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
2200 27, 27, 27, 27, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
2201 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
2202 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
2203 28, 28, 28, 28, 28, 28, 28, 28, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
2204 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
2205 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
2206 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29
2207 };
2208
2209 const uch _length_code[MAX_MATCH-MIN_MATCH+1]= {
2210 0, 1, 2, 3, 4, 5, 6, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 12, 12,
2211 13, 13, 13, 13, 14, 14, 14, 14, 15, 15, 15, 15, 16, 16, 16, 16, 16, 16, 16, 16,
2212 17, 17, 17, 17, 17, 17, 17, 17, 18, 18, 18, 18, 18, 18, 18, 18, 19, 19, 19, 19,
2213 19, 19, 19, 19, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20,
2214 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 22, 22, 22, 22,
2215 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 23, 23, 23, 23, 23, 23, 23, 23,
2216 23, 23, 23, 23, 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
2217 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
2218 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
2219 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 26, 26, 26, 26, 26, 26, 26, 26,
2220 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
2221 26, 26, 26, 26, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
2222 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 28
2223 };
2224
2225 local const int base_length[LENGTH_CODES] = {
2226 0, 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, 16, 20, 24, 28, 32, 40, 48, 56,
2227 64, 80, 96, 112, 128, 160, 192, 224, 0
2228 };
2229
2230 local const int base_dist[D_CODES] = {
2231 0, 1, 2, 3, 4, 6, 8, 12, 16, 24,
2232 32, 48, 64, 96, 128, 192, 256, 384, 512, 768,
2233 1024, 1536, 2048, 3072, 4096, 6144, 8192, 12288, 16384, 24576
2234 };
2235 /* --- trees.h */
2236
2237 #endif /* GEN_TREES_H */
2238
2239 struct static_tree_desc_s {
2240 const ct_data *static_tree; /* static tree or NULL */
2241 const intf *extra_bits; /* extra bits for each code or NULL */
2242 int extra_base; /* base index for extra_bits */
2243 int elems; /* max number of elements in the tree */
2244 int max_length; /* max bit length for the codes */
2245 };
2246
2247 local static_tree_desc static_l_desc =
2248 {static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS};
2249
2250 local static_tree_desc static_d_desc =
2251 {static_dtree, extra_dbits, 0, D_CODES, MAX_BITS};
2252
2253 local static_tree_desc static_bl_desc =
2254 {(const ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS};
2255
2256 /* ===========================================================================
2257 * Local (static) routines in this file.
2258 */
2259
2260 local void tr_static_init __P((void));
2261 local void init_block __P((deflate_state *s));
2262 local void pqdownheap __P((deflate_state *s, ct_data *tree, int k));
2263 local void gen_bitlen __P((deflate_state *s, tree_desc *desc));
2264 local void gen_codes __P((ct_data *tree, int max_code, ushf *bl_count));
2265 local void build_tree __P((deflate_state *s, tree_desc *desc));
2266 local void scan_tree __P((deflate_state *s, ct_data *tree, int max_code));
2267 local void send_tree __P((deflate_state *s, ct_data *tree, int max_code));
2268 local int build_bl_tree __P((deflate_state *s));
2269 local void send_all_trees __P((deflate_state *s, int lcodes, int dcodes,
2270 int blcodes));
2271 local void compress_block __P((deflate_state *s, ct_data *ltree,
2272 ct_data *dtree));
2273 local void set_data_type __P((deflate_state *s));
2274 local unsigned bi_reverse __P((unsigned value, int length));
2275 local void bi_windup __P((deflate_state *s));
2276 local void bi_flush __P((deflate_state *s));
2277 local void copy_block __P((deflate_state *s, charf *buf, unsigned len,
2278 int header));
2279
2280 #ifdef GEN_TREES_H
2281 local void gen_trees_header __P((void));
2282 #endif
2283
2284 #ifndef DEBUG_ZLIB
2285 # define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len)
2286 /* Send a code of the given tree. c and tree must not have side effects */
2287
2288 #else /* DEBUG_ZLIB */
2289 # define send_code(s, c, tree) \
2290 { if (z_verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \
2291 send_bits(s, tree[c].Code, tree[c].Len); }
2292 #endif
2293
2294 /* ===========================================================================
2295 * Output a short LSB first on the stream.
2296 * IN assertion: there is enough room in pendingBuf.
2297 */
2298 #define put_short(s, w) { \
2299 put_byte(s, (uch)((w) & 0xff)); \
2300 put_byte(s, (uch)((ush)(w) >> 8)); \
2301 }
2302
2303 /* ===========================================================================
2304 * Send a value on a given number of bits.
2305 * IN assertion: length <= 16 and value fits in length bits.
2306 */
2307 #ifdef DEBUG_ZLIB
2308 local void send_bits __P((deflate_state *s, int value, int length));
2309
2310 local void send_bits(s, value, length)
2311 deflate_state *s;
2312 int value; /* value to send */
2313 int length; /* number of bits */
2314 {
2315 Tracevv((stderr," l %2d v %4x ", length, value));
2316 Assert(length > 0 && length <= 15, "invalid length");
2317 s->bits_sent += (ulg)length;
2318
2319 /* If not enough room in bi_buf, use (valid) bits from bi_buf and
2320 * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid))
2321 * unused bits in value.
2322 */
2323 if (s->bi_valid > (int)Buf_size - length) {
2324 s->bi_buf |= (value << s->bi_valid);
2325 put_short(s, s->bi_buf);
2326 s->bi_buf = (ush)value >> (Buf_size - s->bi_valid);
2327 s->bi_valid += length - Buf_size;
2328 } else {
2329 s->bi_buf |= value << s->bi_valid;
2330 s->bi_valid += length;
2331 }
2332 }
2333 #else /* !DEBUG_ZLIB */
2334
2335 #define send_bits(s, value, length) \
2336 { int len = length;\
2337 if (s->bi_valid > (int)Buf_size - len) {\
2338 int val = value;\
2339 s->bi_buf |= (val << s->bi_valid);\
2340 put_short(s, s->bi_buf);\
2341 s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\
2342 s->bi_valid += len - Buf_size;\
2343 } else {\
2344 s->bi_buf |= (value) << s->bi_valid;\
2345 s->bi_valid += len;\
2346 }\
2347 }
2348 #endif /* DEBUG_ZLIB */
2349
2350
2351 /* ===========================================================================
2352 * Initialize the various 'constant' tables.
2353 */
2354 local void tr_static_init()
2355 {
2356 #if defined(GEN_TREES_H) || !defined(STDC)
2357 static int static_init_done = 0;
2358 int n; /* iterates over tree elements */
2359 int bits; /* bit counter */
2360 int length; /* length value */
2361 int code; /* code value */
2362 int dist; /* distance index */
2363 ush bl_count[MAX_BITS+1];
2364 /* number of codes at each bit length for an optimal tree */
2365
2366 if (static_init_done) return;
2367
2368 /* For some embedded targets, global variables are not initialized: */
2369 static_l_desc.static_tree = static_ltree;
2370 static_l_desc.extra_bits = extra_lbits;
2371 static_d_desc.static_tree = static_dtree;
2372 static_d_desc.extra_bits = extra_dbits;
2373 static_bl_desc.extra_bits = extra_blbits;
2374
2375 /* Initialize the mapping length (0..255) -> length code (0..28) */
2376 length = 0;
2377 for (code = 0; code < LENGTH_CODES-1; code++) {
2378 base_length[code] = length;
2379 for (n = 0; n < (1<<extra_lbits[code]); n++) {
2380 _length_code[length++] = (uch)code;
2381 }
2382 }
2383 Assert (length == 256, "tr_static_init: length != 256");
2384 /* Note that the length 255 (match length 258) can be represented
2385 * in two different ways: code 284 + 5 bits or code 285, so we
2386 * overwrite length_code[255] to use the best encoding:
2387 */
2388 _length_code[length-1] = (uch)code;
2389
2390 /* Initialize the mapping dist (0..32K) -> dist code (0..29) */
2391 dist = 0;
2392 for (code = 0 ; code < 16; code++) {
2393 base_dist[code] = dist;
2394 for (n = 0; n < (1<<extra_dbits[code]); n++) {
2395 _dist_code[dist++] = (uch)code;
2396 }
2397 }
2398 Assert (dist == 256, "tr_static_init: dist != 256");
2399 dist >>= 7; /* from now on, all distances are divided by 128 */
2400 for ( ; code < D_CODES; code++) {
2401 base_dist[code] = dist << 7;
2402 for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) {
2403 _dist_code[256 + dist++] = (uch)code;
2404 }
2405 }
2406 Assert (dist == 256, "tr_static_init: 256+dist != 512");
2407
2408 /* Construct the codes of the static literal tree */
2409 for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
2410 n = 0;
2411 while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++;
2412 while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++;
2413 while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++;
2414 while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++;
2415 /* Codes 286 and 287 do not exist, but we must include them in the
2416 * tree construction to get a canonical Huffman tree (longest code
2417 * all ones)
2418 */
2419 gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count);
2420
2421 /* The static distance tree is trivial: */
2422 for (n = 0; n < D_CODES; n++) {
2423 static_dtree[n].Len = 5;
2424 static_dtree[n].Code = bi_reverse((unsigned)n, 5);
2425 }
2426 static_init_done = 1;
2427
2428 # ifdef GEN_TREES_H
2429 gen_trees_header();
2430 # endif
2431 #endif /* defined(GEN_TREES_H) || !defined(STDC) */
2432 }
2433
2434 /* ===========================================================================
2435 * Genererate the file trees.h describing the static trees.
2436 */
2437 #ifdef GEN_TREES_H
2438 # ifndef DEBUG_ZLIB
2439 # include <stdio.h>
2440 # endif
2441
2442 # define SEPARATOR(i, last, width) \
2443 ((i) == (last)? "\n};\n\n" : \
2444 ((i) % (width) == (width)-1 ? ",\n" : ", "))
2445
2446 void gen_trees_header()
2447 {
2448 FILE *header = fopen("trees.h", "w");
2449 int i;
2450
2451 Assert (header != NULL, "Can't open trees.h");
2452 fprintf(header,
2453 "/* header created automatically with -DGEN_TREES_H */\n\n");
2454
2455 fprintf(header, "local const ct_data static_ltree[L_CODES+2] = {\n");
2456 for (i = 0; i < L_CODES+2; i++) {
2457 fprintf(header, "{{%3u},{%3u}}%s", static_ltree[i].Code,
2458 static_ltree[i].Len, SEPARATOR(i, L_CODES+1, 5));
2459 }
2460
2461 fprintf(header, "local const ct_data static_dtree[D_CODES] = {\n");
2462 for (i = 0; i < D_CODES; i++) {
2463 fprintf(header, "{{%2u},{%2u}}%s", static_dtree[i].Code,
2464 static_dtree[i].Len, SEPARATOR(i, D_CODES-1, 5));
2465 }
2466
2467 fprintf(header, "const uch _dist_code[DIST_CODE_LEN] = {\n");
2468 for (i = 0; i < DIST_CODE_LEN; i++) {
2469 fprintf(header, "%2u%s", _dist_code[i],
2470 SEPARATOR(i, DIST_CODE_LEN-1, 20));
2471 }
2472
2473 fprintf(header, "const uch _length_code[MAX_MATCH-MIN_MATCH+1]= {\n");
2474 for (i = 0; i < MAX_MATCH-MIN_MATCH+1; i++) {
2475 fprintf(header, "%2u%s", _length_code[i],
2476 SEPARATOR(i, MAX_MATCH-MIN_MATCH, 20));
2477 }
2478
2479 fprintf(header, "local const int base_length[LENGTH_CODES] = {\n");
2480 for (i = 0; i < LENGTH_CODES; i++) {
2481 fprintf(header, "%1u%s", base_length[i],
2482 SEPARATOR(i, LENGTH_CODES-1, 20));
2483 }
2484
2485 fprintf(header, "local const int base_dist[D_CODES] = {\n");
2486 for (i = 0; i < D_CODES; i++) {
2487 fprintf(header, "%5u%s", base_dist[i],
2488 SEPARATOR(i, D_CODES-1, 10));
2489 }
2490
2491 fclose(header);
2492 }
2493 #endif /* GEN_TREES_H */
2494
2495 /* ===========================================================================
2496 * Initialize the tree data structures for a new zlib stream.
2497 */
2498 void _tr_init(s)
2499 deflate_state *s;
2500 {
2501 tr_static_init();
2502
2503 s->l_desc.dyn_tree = s->dyn_ltree;
2504 s->l_desc.stat_desc = &static_l_desc;
2505
2506 s->d_desc.dyn_tree = s->dyn_dtree;
2507 s->d_desc.stat_desc = &static_d_desc;
2508
2509 s->bl_desc.dyn_tree = s->bl_tree;
2510 s->bl_desc.stat_desc = &static_bl_desc;
2511
2512 s->bi_buf = 0;
2513 s->bi_valid = 0;
2514 s->last_eob_len = 8; /* enough lookahead for inflate */
2515 #ifdef DEBUG_ZLIB
2516 s->compressed_len = 0L;
2517 s->bits_sent = 0L;
2518 #endif
2519
2520 /* Initialize the first block of the first file: */
2521 init_block(s);
2522 }
2523
2524 /* ===========================================================================
2525 * Initialize a new block.
2526 */
2527 local void init_block(s)
2528 deflate_state *s;
2529 {
2530 int n; /* iterates over tree elements */
2531
2532 /* Initialize the trees. */
2533 for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0;
2534 for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0;
2535 for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0;
2536
2537 s->dyn_ltree[END_BLOCK].Freq = 1;
2538 s->opt_len = s->static_len = 0L;
2539 s->last_lit = s->matches = 0;
2540 }
2541
2542 #define SMALLEST 1
2543 /* Index within the heap array of least frequent node in the Huffman tree */
2544
2545
2546 /* ===========================================================================
2547 * Remove the smallest element from the heap and recreate the heap with
2548 * one less element. Updates heap and heap_len.
2549 */
2550 #define pqremove(s, tree, top) \
2551 {\
2552 top = s->heap[SMALLEST]; \
2553 s->heap[SMALLEST] = s->heap[s->heap_len--]; \
2554 pqdownheap(s, tree, SMALLEST); \
2555 }
2556
2557 /* ===========================================================================
2558 * Compares to subtrees, using the tree depth as tie breaker when
2559 * the subtrees have equal frequency. This minimizes the worst case length.
2560 */
2561 #define smaller(tree, n, m, depth) \
2562 (tree[n].Freq < tree[m].Freq || \
2563 (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m]))
2564
2565 /* ===========================================================================
2566 * Restore the heap property by moving down the tree starting at node k,
2567 * exchanging a node with the smallest of its two sons if necessary, stopping
2568 * when the heap property is re-established (each father smaller than its
2569 * two sons).
2570 */
2571 local void pqdownheap(s, tree, k)
2572 deflate_state *s;
2573 ct_data *tree; /* the tree to restore */
2574 int k; /* node to move down */
2575 {
2576 int v = s->heap[k];
2577 int j = k << 1; /* left son of k */
2578 while (j <= s->heap_len) {
2579 /* Set j to the smallest of the two sons: */
2580 if (j < s->heap_len &&
2581 smaller(tree, s->heap[j+1], s->heap[j], s->depth)) {
2582 j++;
2583 }
2584 /* Exit if v is smaller than both sons */
2585 if (smaller(tree, v, s->heap[j], s->depth)) break;
2586
2587 /* Exchange v with the smallest son */
2588 s->heap[k] = s->heap[j]; k = j;
2589
2590 /* And continue down the tree, setting j to the left son of k */
2591 j <<= 1;
2592 }
2593 s->heap[k] = v;
2594 }
2595
2596 /* ===========================================================================
2597 * Compute the optimal bit lengths for a tree and update the total bit length
2598 * for the current block.
2599 * IN assertion: the fields freq and dad are set, heap[heap_max] and
2600 * above are the tree nodes sorted by increasing frequency.
2601 * OUT assertions: the field len is set to the optimal bit length, the
2602 * array bl_count contains the frequencies for each bit length.
2603 * The length opt_len is updated; static_len is also updated if stree is
2604 * not null.
2605 */
2606 local void gen_bitlen(s, desc)
2607 deflate_state *s;
2608 tree_desc *desc; /* the tree descriptor */
2609 {
2610 ct_data *tree = desc->dyn_tree;
2611 int max_code = desc->max_code;
2612 const ct_data *stree = desc->stat_desc->static_tree;
2613 const intf *extra = desc->stat_desc->extra_bits;
2614 int base = desc->stat_desc->extra_base;
2615 int max_length = desc->stat_desc->max_length;
2616 int h; /* heap index */
2617 int n, m; /* iterate over the tree elements */
2618 int bits; /* bit length */
2619 int xbits; /* extra bits */
2620 ush f; /* frequency */
2621 int overflow = 0; /* number of elements with bit length too large */
2622
2623 for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0;
2624
2625 /* In a first pass, compute the optimal bit lengths (which may
2626 * overflow in the case of the bit length tree).
2627 */
2628 tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */
2629
2630 for (h = s->heap_max+1; h < HEAP_SIZE; h++) {
2631 n = s->heap[h];
2632 bits = tree[tree[n].Dad].Len + 1;
2633 if (bits > max_length) bits = max_length, overflow++;
2634 tree[n].Len = (ush)bits;
2635 /* We overwrite tree[n].Dad which is no longer needed */
2636
2637 if (n > max_code) continue; /* not a leaf node */
2638
2639 s->bl_count[bits]++;
2640 xbits = 0;
2641 if (n >= base) xbits = extra[n-base];
2642 f = tree[n].Freq;
2643 s->opt_len += (ulg)f * (bits + xbits);
2644 if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits);
2645 }
2646 if (overflow == 0) return;
2647
2648 Trace((stderr,"\nbit length overflow\n"));
2649 /* This happens for example on obj2 and pic of the Calgary corpus */
2650
2651 /* Find the first bit length which could increase: */
2652 do {
2653 bits = max_length-1;
2654 while (s->bl_count[bits] == 0) bits--;
2655 s->bl_count[bits]--; /* move one leaf down the tree */
2656 s->bl_count[bits+1] += 2; /* move one overflow item as its brother */
2657 s->bl_count[max_length]--;
2658 /* The brother of the overflow item also moves one step up,
2659 * but this does not affect bl_count[max_length]
2660 */
2661 overflow -= 2;
2662 } while (overflow > 0);
2663
2664 /* Now recompute all bit lengths, scanning in increasing frequency.
2665 * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
2666 * lengths instead of fixing only the wrong ones. This idea is taken
2667 * from 'ar' written by Haruhiko Okumura.)
2668 */
2669 for (bits = max_length; bits != 0; bits--) {
2670 n = s->bl_count[bits];
2671 while (n != 0) {
2672 m = s->heap[--h];
2673 if (m > max_code) continue;
2674 if (tree[m].Len != (unsigned) bits) {
2675 Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits));
2676 s->opt_len += ((long)bits - (long)tree[m].Len)
2677 *(long)tree[m].Freq;
2678 tree[m].Len = (ush)bits;
2679 }
2680 n--;
2681 }
2682 }
2683 }
2684
2685 /* ===========================================================================
2686 * Generate the codes for a given tree and bit counts (which need not be
2687 * optimal).
2688 * IN assertion: the array bl_count contains the bit length statistics for
2689 * the given tree and the field len is set for all tree elements.
2690 * OUT assertion: the field code is set for all tree elements of non
2691 * zero code length.
2692 */
2693 local void gen_codes (tree, max_code, bl_count)
2694 ct_data *tree; /* the tree to decorate */
2695 int max_code; /* largest code with non zero frequency */
2696 ushf *bl_count; /* number of codes at each bit length */
2697 {
2698 ush next_code[MAX_BITS+1]; /* next code value for each bit length */
2699 ush code = 0; /* running code value */
2700 int bits; /* bit index */
2701 int n; /* code index */
2702
2703 /* The distribution counts are first used to generate the code values
2704 * without bit reversal.
2705 */
2706 for (bits = 1; bits <= MAX_BITS; bits++) {
2707 next_code[bits] = code = (code + bl_count[bits-1]) << 1;
2708 }
2709 /* Check that the bit counts in bl_count are consistent. The last code
2710 * must be all ones.
2711 */
2712 Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1,
2713 "inconsistent bit counts");
2714 Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
2715
2716 for (n = 0; n <= max_code; n++) {
2717 int len = tree[n].Len;
2718 if (len == 0) continue;
2719 /* Now reverse the bits */
2720 tree[n].Code = bi_reverse(next_code[len]++, len);
2721
2722 Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
2723 n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1));
2724 }
2725 }
2726
2727 /* ===========================================================================
2728 * Construct one Huffman tree and assigns the code bit strings and lengths.
2729 * Update the total bit length for the current block.
2730 * IN assertion: the field freq is set for all tree elements.
2731 * OUT assertions: the fields len and code are set to the optimal bit length
2732 * and corresponding code. The length opt_len is updated; static_len is
2733 * also updated if stree is not null. The field max_code is set.
2734 */
2735 local void build_tree(s, desc)
2736 deflate_state *s;
2737 tree_desc *desc; /* the tree descriptor */
2738 {
2739 ct_data *tree = desc->dyn_tree;
2740 const ct_data *stree = desc->stat_desc->static_tree;
2741 int elems = desc->stat_desc->elems;
2742 int n, m; /* iterate over heap elements */
2743 int max_code = -1; /* largest code with non zero frequency */
2744 int node; /* new node being created */
2745
2746 /* Construct the initial heap, with least frequent element in
2747 * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
2748 * heap[0] is not used.
2749 */
2750 s->heap_len = 0, s->heap_max = HEAP_SIZE;
2751
2752 for (n = 0; n < elems; n++) {
2753 if (tree[n].Freq != 0) {
2754 s->heap[++(s->heap_len)] = max_code = n;
2755 s->depth[n] = 0;
2756 } else {
2757 tree[n].Len = 0;
2758 }
2759 }
2760
2761 /* The pkzip format requires that at least one distance code exists,
2762 * and that at least one bit should be sent even if there is only one
2763 * possible code. So to avoid special checks later on we force at least
2764 * two codes of non zero frequency.
2765 */
2766 while (s->heap_len < 2) {
2767 node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0);
2768 tree[node].Freq = 1;
2769 s->depth[node] = 0;
2770 s->opt_len--; if (stree) s->static_len -= stree[node].Len;
2771 /* node is 0 or 1 so it does not have extra bits */
2772 }
2773 desc->max_code = max_code;
2774
2775 /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
2776 * establish sub-heaps of increasing lengths:
2777 */
2778 for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n);
2779
2780 /* Construct the Huffman tree by repeatedly combining the least two
2781 * frequent nodes.
2782 */
2783 node = elems; /* next internal node of the tree */
2784 do {
2785 pqremove(s, tree, n); /* n = node of least frequency */
2786 m = s->heap[SMALLEST]; /* m = node of next least frequency */
2787
2788 s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */
2789 s->heap[--(s->heap_max)] = m;
2790
2791 /* Create a new node father of n and m */
2792 tree[node].Freq = tree[n].Freq + tree[m].Freq;
2793 s->depth[node] = (uch) (MAX(s->depth[n], s->depth[m]) + 1);
2794 tree[n].Dad = tree[m].Dad = (ush)node;
2795 #ifdef DUMP_BL_TREE
2796 if (tree == s->bl_tree) {
2797 fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)",
2798 node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq);
2799 }
2800 #endif
2801 /* and insert the new node in the heap */
2802 s->heap[SMALLEST] = node++;
2803 pqdownheap(s, tree, SMALLEST);
2804
2805 } while (s->heap_len >= 2);
2806
2807 s->heap[--(s->heap_max)] = s->heap[SMALLEST];
2808
2809 /* At this point, the fields freq and dad are set. We can now
2810 * generate the bit lengths.
2811 */
2812 gen_bitlen(s, (tree_desc *)desc);
2813
2814 /* The field len is now set, we can generate the bit codes */
2815 gen_codes ((ct_data *)tree, max_code, s->bl_count);
2816 }
2817
2818 /* ===========================================================================
2819 * Scan a literal or distance tree to determine the frequencies of the codes
2820 * in the bit length tree.
2821 */
2822 local void scan_tree (s, tree, max_code)
2823 deflate_state *s;
2824 ct_data *tree; /* the tree to be scanned */
2825 int max_code; /* and its largest code of non zero frequency */
2826 {
2827 int n; /* iterates over all tree elements */
2828 int prevlen = -1; /* last emitted length */
2829 int curlen; /* length of current code */
2830 int nextlen = tree[0].Len; /* length of next code */
2831 int count = 0; /* repeat count of the current code */
2832 int max_count = 7; /* max repeat count */
2833 int min_count = 4; /* min repeat count */
2834
2835 if (nextlen == 0) max_count = 138, min_count = 3;
2836 tree[max_code+1].Len = (ush)0xffff; /* guard */
2837
2838 for (n = 0; n <= max_code; n++) {
2839 curlen = nextlen; nextlen = tree[n+1].Len;
2840 if (++count < max_count && curlen == nextlen) {
2841 continue;
2842 } else if (count < min_count) {
2843 s->bl_tree[curlen].Freq += count;
2844 } else if (curlen != 0) {
2845 if (curlen != prevlen) s->bl_tree[curlen].Freq++;
2846 s->bl_tree[REP_3_6].Freq++;
2847 } else if (count <= 10) {
2848 s->bl_tree[REPZ_3_10].Freq++;
2849 } else {
2850 s->bl_tree[REPZ_11_138].Freq++;
2851 }
2852 count = 0; prevlen = curlen;
2853 if (nextlen == 0) {
2854 max_count = 138, min_count = 3;
2855 } else if (curlen == nextlen) {
2856 max_count = 6, min_count = 3;
2857 } else {
2858 max_count = 7, min_count = 4;
2859 }
2860 }
2861 }
2862
2863 /* ===========================================================================
2864 * Send a literal or distance tree in compressed form, using the codes in
2865 * bl_tree.
2866 */
2867 local void send_tree (s, tree, max_code)
2868 deflate_state *s;
2869 ct_data *tree; /* the tree to be scanned */
2870 int max_code; /* and its largest code of non zero frequency */
2871 {
2872 int n; /* iterates over all tree elements */
2873 int prevlen = -1; /* last emitted length */
2874 int curlen; /* length of current code */
2875 int nextlen = tree[0].Len; /* length of next code */
2876 int count = 0; /* repeat count of the current code */
2877 int max_count = 7; /* max repeat count */
2878 int min_count = 4; /* min repeat count */
2879
2880 /* tree[max_code+1].Len = -1; */ /* guard already set */
2881 if (nextlen == 0) max_count = 138, min_count = 3;
2882
2883 for (n = 0; n <= max_code; n++) {
2884 curlen = nextlen; nextlen = tree[n+1].Len;
2885 if (++count < max_count && curlen == nextlen) {
2886 continue;
2887 } else if (count < min_count) {
2888 do { send_code(s, curlen, s->bl_tree); } while (--count != 0);
2889
2890 } else if (curlen != 0) {
2891 if (curlen != prevlen) {
2892 send_code(s, curlen, s->bl_tree); count--;
2893 }
2894 Assert(count >= 3 && count <= 6, " 3_6?");
2895 send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2);
2896
2897 } else if (count <= 10) {
2898 send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3);
2899
2900 } else {
2901 send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7);
2902 }
2903 count = 0; prevlen = curlen;
2904 if (nextlen == 0) {
2905 max_count = 138, min_count = 3;
2906 } else if (curlen == nextlen) {
2907 max_count = 6, min_count = 3;
2908 } else {
2909 max_count = 7, min_count = 4;
2910 }
2911 }
2912 }
2913
2914 /* ===========================================================================
2915 * Construct the Huffman tree for the bit lengths and return the index in
2916 * bl_order of the last bit length code to send.
2917 */
2918 local int build_bl_tree(s)
2919 deflate_state *s;
2920 {
2921 int max_blindex; /* index of last bit length code of non zero freq */
2922
2923 /* Determine the bit length frequencies for literal and distance trees */
2924 scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code);
2925 scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code);
2926
2927 /* Build the bit length tree: */
2928 build_tree(s, (tree_desc *)(&(s->bl_desc)));
2929 /* opt_len now includes the length of the tree representations, except
2930 * the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
2931 */
2932
2933 /* Determine the number of bit length codes to send. The pkzip format
2934 * requires that at least 4 bit length codes be sent. (appnote.txt says
2935 * 3 but the actual value used is 4.)
2936 */
2937 for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) {
2938 if (s->bl_tree[bl_order[max_blindex]].Len != 0) break;
2939 }
2940 /* Update opt_len to include the bit length tree and counts */
2941 s->opt_len += 3*(max_blindex+1) + 5+5+4;
2942 Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld",
2943 s->opt_len, s->static_len));
2944
2945 return max_blindex;
2946 }
2947
2948 /* ===========================================================================
2949 * Send the header for a block using dynamic Huffman trees: the counts, the
2950 * lengths of the bit length codes, the literal tree and the distance tree.
2951 * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
2952 */
2953 local void send_all_trees(s, lcodes, dcodes, blcodes)
2954 deflate_state *s;
2955 int lcodes, dcodes, blcodes; /* number of codes for each tree */
2956 {
2957 int rank; /* index in bl_order */
2958
2959 Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
2960 Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
2961 "too many codes");
2962 Tracev((stderr, "\nbl counts: "));
2963 send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */
2964 send_bits(s, dcodes-1, 5);
2965 send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */
2966 for (rank = 0; rank < blcodes; rank++) {
2967 Tracev((stderr, "\nbl code %2d ", bl_order[rank]));
2968 send_bits(s, s->bl_tree[bl_order[rank]].Len, 3);
2969 }
2970 Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent));
2971
2972 send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */
2973 Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent));
2974
2975 send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */
2976 Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent));
2977 }
2978
2979 /* ===========================================================================
2980 * Send a stored block
2981 */
2982 void _tr_stored_block(s, buf, stored_len, eof)
2983 deflate_state *s;
2984 charf *buf; /* input block */
2985 ulg stored_len; /* length of input block */
2986 int eof; /* true if this is the last block for a file */
2987 {
2988 send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */
2989 #ifdef DEBUG_ZLIB
2990 s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L;
2991 s->compressed_len += (stored_len + 4) << 3;
2992 #endif
2993 copy_block(s, buf, (unsigned)stored_len, 1); /* with header */
2994 }
2995
2996 /* Send just the `stored block' type code without any length bytes or data.
2997 */
2998 void _tr_stored_type_only(s)
2999 deflate_state *s;
3000 {
3001 send_bits(s, (STORED_BLOCK << 1), 3);
3002 bi_windup(s);
3003 #ifdef DEBUG_ZLIB
3004 s->compressed_len = (s->compressed_len + 3) & ~7L;
3005 #endif
3006 }
3007
3008 /* ===========================================================================
3009 * Send one empty static block to give enough lookahead for inflate.
3010 * This takes 10 bits, of which 7 may remain in the bit buffer.
3011 * The current inflate code requires 9 bits of lookahead. If the
3012 * last two codes for the previous block (real code plus EOB) were coded
3013 * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode
3014 * the last real code. In this case we send two empty static blocks instead
3015 * of one. (There are no problems if the previous block is stored or fixed.)
3016 * To simplify the code, we assume the worst case of last real code encoded
3017 * on one bit only.
3018 */
3019 void _tr_align(s)
3020 deflate_state *s;
3021 {
3022 send_bits(s, STATIC_TREES<<1, 3);
3023 send_code(s, END_BLOCK, static_ltree);
3024 #ifdef DEBUG_ZLIB
3025 s->compressed_len += 10L; /* 3 for block type, 7 for EOB */
3026 #endif
3027 bi_flush(s);
3028 /* Of the 10 bits for the empty block, we have already sent
3029 * (10 - bi_valid) bits. The lookahead for the last real code (before
3030 * the EOB of the previous block) was thus at least one plus the length
3031 * of the EOB plus what we have just sent of the empty static block.
3032 */
3033 if (1 + s->last_eob_len + 10 - s->bi_valid < 9) {
3034 send_bits(s, STATIC_TREES<<1, 3);
3035 send_code(s, END_BLOCK, static_ltree);
3036 #ifdef DEBUG_ZLIB
3037 s->compressed_len += 10L;
3038 #endif
3039 bi_flush(s);
3040 }
3041 s->last_eob_len = 7;
3042 }
3043
3044 /* ===========================================================================
3045 * Determine the best encoding for the current block: dynamic trees, static
3046 * trees or store, and output the encoded block to the zip file.
3047 */
3048 void _tr_flush_block(s, buf, stored_len, eof)
3049 deflate_state *s;
3050 charf *buf; /* input block, or NULL if too old */
3051 ulg stored_len; /* length of input block */
3052 int eof; /* true if this is the last block for a file */
3053 {
3054 ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
3055 int max_blindex = 0; /* index of last bit length code of non zero freq */
3056
3057 /* Build the Huffman trees unless a stored block is forced */
3058 if (s->level > 0) {
3059
3060 /* Check if the file is ascii or binary */
3061 if (s->data_type == Z_UNKNOWN) set_data_type(s);
3062
3063 /* Construct the literal and distance trees */
3064 build_tree(s, (tree_desc *)(&(s->l_desc)));
3065 Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len,
3066 s->static_len));
3067
3068 build_tree(s, (tree_desc *)(&(s->d_desc)));
3069 Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len,
3070 s->static_len));
3071 /* At this point, opt_len and static_len are the total bit lengths of
3072 * the compressed block data, excluding the tree representations.
3073 */
3074
3075 /* Build the bit length tree for the above two trees, and get the index
3076 * in bl_order of the last bit length code to send.
3077 */
3078 max_blindex = build_bl_tree(s);
3079
3080 /* Determine the best encoding. Compute first the block length in bytes*/
3081 opt_lenb = (s->opt_len+3+7)>>3;
3082 static_lenb = (s->static_len+3+7)>>3;
3083
3084 Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
3085 opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
3086 s->last_lit));
3087
3088 if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
3089
3090 } else {
3091 Assert(buf != (char*)0, "lost buf");
3092 opt_lenb = static_lenb = stored_len + 5; /* force a stored block */
3093 }
3094
3095 #ifdef FORCE_STORED
3096 if (buf != (char*)0) { /* force stored block */
3097 #else
3098 if (stored_len+4 <= opt_lenb && buf != (char*)0) {
3099 /* 4: two words for the lengths */
3100 #endif
3101 /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
3102 * Otherwise we can't have processed more than WSIZE input bytes since
3103 * the last block flush, because compression would have been
3104 * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
3105 * transform a block into a stored block.
3106 */
3107 _tr_stored_block(s, buf, stored_len, eof);
3108
3109 #ifdef FORCE_STATIC
3110 } else if (static_lenb >= 0) { /* force static trees */
3111 #else
3112 } else if (static_lenb == opt_lenb) {
3113 #endif
3114 send_bits(s, (STATIC_TREES<<1)+eof, 3);
3115 compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree);
3116 #ifdef DEBUG_ZLIB
3117 s->compressed_len += 3 + s->static_len;
3118 #endif
3119 } else {
3120 send_bits(s, (DYN_TREES<<1)+eof, 3);
3121 send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1,
3122 max_blindex+1);
3123 compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree);
3124 #ifdef DEBUG_ZLIB
3125 s->compressed_len += 3 + s->opt_len;
3126 #endif
3127 }
3128 Assert (s->compressed_len == s->bits_sent, "bad compressed size");
3129 /* The above check is made mod 2^32, for files larger than 512 MB
3130 * and uLong implemented on 32 bits.
3131 */
3132 init_block(s);
3133
3134 if (eof) {
3135 bi_windup(s);
3136 #ifdef DEBUG_ZLIB
3137 s->compressed_len += 7; /* align on byte boundary */
3138 #endif
3139 }
3140 Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3,
3141 s->compressed_len-7*eof));
3142 }
3143
3144 /* ===========================================================================
3145 * Save the match info and tally the frequency counts. Return true if
3146 * the current block must be flushed.
3147 */
3148 int _tr_tally (s, dist, lc)
3149 deflate_state *s;
3150 unsigned dist; /* distance of matched string */
3151 unsigned lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */
3152 {
3153 s->d_buf[s->last_lit] = (ush)dist;
3154 s->l_buf[s->last_lit++] = (uch)lc;
3155 if (dist == 0) {
3156 /* lc is the unmatched char */
3157 s->dyn_ltree[lc].Freq++;
3158 } else {
3159 s->matches++;
3160 /* Here, lc is the match length - MIN_MATCH */
3161 dist--; /* dist = match distance - 1 */
3162 Assert((ush)dist < (ush)MAX_DIST(s) &&
3163 (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
3164 (ush)d_code(dist) < (ush)D_CODES, "_tr_tally: bad match");
3165
3166 s->dyn_ltree[_length_code[lc]+LITERALS+1].Freq++;
3167 s->dyn_dtree[d_code(dist)].Freq++;
3168 }
3169
3170 #ifdef TRUNCATE_BLOCK
3171 /* Try to guess if it is profitable to stop the current block here */
3172 if ((s->last_lit & 0x1fff) == 0 && s->level > 2) {
3173 /* Compute an upper bound for the compressed length */
3174 ulg out_length = (ulg)s->last_lit*8L;
3175 ulg in_length = (ulg)((long)s->strstart - s->block_start);
3176 int dcode;
3177 for (dcode = 0; dcode < D_CODES; dcode++) {
3178 out_length += (ulg)s->dyn_dtree[dcode].Freq *
3179 (5L+extra_dbits[dcode]);
3180 }
3181 out_length >>= 3;
3182 Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ",
3183 s->last_lit, in_length, out_length,
3184 100L - out_length*100L/in_length));
3185 if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1;
3186 }
3187 #endif
3188 return (s->last_lit == s->lit_bufsize-1);
3189 /* We avoid equality with lit_bufsize because of wraparound at 64K
3190 * on 16 bit machines and because stored blocks are restricted to
3191 * 64K-1 bytes.
3192 */
3193 }
3194
3195 /* ===========================================================================
3196 * Send the block data compressed using the given Huffman trees
3197 */
3198 local void compress_block(s, ltree, dtree)
3199 deflate_state *s;
3200 ct_data *ltree; /* literal tree */
3201 ct_data *dtree; /* distance tree */
3202 {
3203 unsigned dist; /* distance of matched string */
3204 int lc; /* match length or unmatched char (if dist == 0) */
3205 unsigned lx = 0; /* running index in l_buf */
3206 unsigned code; /* the code to send */
3207 int extra; /* number of extra bits to send */
3208
3209 if (s->last_lit != 0) do {
3210 dist = s->d_buf[lx];
3211 lc = s->l_buf[lx++];
3212 if (dist == 0) {
3213 send_code(s, lc, ltree); /* send a literal byte */
3214 Tracecv(isgraph(lc), (stderr," '%c' ", lc));
3215 } else {
3216 /* Here, lc is the match length - MIN_MATCH */
3217 code = _length_code[lc];
3218 send_code(s, code+LITERALS+1, ltree); /* send the length code */
3219 extra = extra_lbits[code];
3220 if (extra != 0) {
3221 lc -= base_length[code];
3222 send_bits(s, lc, extra); /* send the extra length bits */
3223 }
3224 dist--; /* dist is now the match distance - 1 */
3225 code = d_code(dist);
3226 Assert (code < D_CODES, "bad d_code");
3227
3228 send_code(s, code, dtree); /* send the distance code */
3229 extra = extra_dbits[code];
3230 if (extra != 0) {
3231 dist -= base_dist[code];
3232 send_bits(s, dist, extra); /* send the extra distance bits */
3233 }
3234 } /* literal or match pair ? */
3235
3236 /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */
3237 Assert(s->pending < s->lit_bufsize + 2*lx, "pendingBuf overflow");
3238
3239 } while (lx < s->last_lit);
3240
3241 send_code(s, END_BLOCK, ltree);
3242 s->last_eob_len = ltree[END_BLOCK].Len;
3243 }
3244
3245 /* ===========================================================================
3246 * Set the data type to ASCII or BINARY, using a crude approximation:
3247 * binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise.
3248 * IN assertion: the fields freq of dyn_ltree are set and the total of all
3249 * frequencies does not exceed 64K (to fit in an int on 16 bit machines).
3250 */
3251 local void set_data_type(s)
3252 deflate_state *s;
3253 {
3254 int n = 0;
3255 unsigned ascii_freq = 0;
3256 unsigned bin_freq = 0;
3257 while (n < 7) bin_freq += s->dyn_ltree[n++].Freq;
3258 while (n < 128) ascii_freq += s->dyn_ltree[n++].Freq;
3259 while (n < LITERALS) bin_freq += s->dyn_ltree[n++].Freq;
3260 s->data_type = (Byte)(bin_freq > (ascii_freq >> 2) ? Z_BINARY : Z_ASCII);
3261 }
3262
3263 /* ===========================================================================
3264 * Reverse the first len bits of a code, using straightforward code (a faster
3265 * method would use a table)
3266 * IN assertion: 1 <= len <= 15
3267 */
3268 local unsigned bi_reverse(code, len)
3269 unsigned code; /* the value to invert */
3270 int len; /* its bit length */
3271 {
3272 unsigned res = 0;
3273 do {
3274 res |= code & 1;
3275 code >>= 1, res <<= 1;
3276 } while (--len > 0);
3277 return res >> 1;
3278 }
3279
3280 /* ===========================================================================
3281 * Flush the bit buffer, keeping at most 7 bits in it.
3282 */
3283 local void bi_flush(s)
3284 deflate_state *s;
3285 {
3286 if (s->bi_valid == 16) {
3287 put_short(s, s->bi_buf);
3288 s->bi_buf = 0;
3289 s->bi_valid = 0;
3290 } else if (s->bi_valid >= 8) {
3291 put_byte(s, (Byte)s->bi_buf);
3292 s->bi_buf >>= 8;
3293 s->bi_valid -= 8;
3294 }
3295 }
3296
3297 /* ===========================================================================
3298 * Flush the bit buffer and align the output on a byte boundary
3299 */
3300 local void bi_windup(s)
3301 deflate_state *s;
3302 {
3303 if (s->bi_valid > 8) {
3304 put_short(s, s->bi_buf);
3305 } else if (s->bi_valid > 0) {
3306 put_byte(s, (Byte)s->bi_buf);
3307 }
3308 s->bi_buf = 0;
3309 s->bi_valid = 0;
3310 #ifdef DEBUG_ZLIB
3311 s->bits_sent = (s->bits_sent+7) & ~7;
3312 #endif
3313 }
3314
3315 /* ===========================================================================
3316 * Copy a stored block, storing first the length and its
3317 * one's complement if requested.
3318 */
3319 local void copy_block(s, buf, len, header)
3320 deflate_state *s;
3321 charf *buf; /* the input data */
3322 unsigned len; /* its length */
3323 int header; /* true if block header must be written */
3324 {
3325 bi_windup(s); /* align on byte boundary */
3326 s->last_eob_len = 8; /* enough lookahead for inflate */
3327
3328 if (header) {
3329 put_short(s, (ush)len);
3330 put_short(s, (ush)~len);
3331 #ifdef DEBUG_ZLIB
3332 s->bits_sent += 2*16;
3333 #endif
3334 }
3335 #ifdef DEBUG_ZLIB
3336 s->bits_sent += (ulg)len<<3;
3337 #endif
3338 /* bundle up the put_byte(s, *buf++) calls */
3339 zmemcpy(&s->pending_buf[s->pending], buf, len);
3340 s->pending += len;
3341 }
3342 /* --- trees.c */
3343
3344 /* +++ inflate.c */
3345
3346 /* inflate.c -- zlib interface to inflate modules
3347 * Copyright (C) 1995-2002 Mark Adler
3348 * For conditions of distribution and use, see copyright notice in zlib.h
3349 */
3350
3351 /* #include "zutil.h" */
3352
3353 /* +++ infblock.h */
3354
3355 /* infblock.h -- header to use infblock.c
3356 * Copyright (C) 1995-2002 Mark Adler
3357 * For conditions of distribution and use, see copyright notice in zlib.h
3358 */
3359
3360 /* WARNING: this file should *not* be used by applications. It is
3361 part of the implementation of the compression library and is
3362 subject to change. Applications should only use zlib.h.
3363 */
3364
3365 struct inflate_blocks_state;
3366 typedef struct inflate_blocks_state FAR inflate_blocks_statef;
3367
3368 extern inflate_blocks_statef * inflate_blocks_new __P((
3369 z_streamp z,
3370 check_func c, /* check function */
3371 uInt w)); /* window size */
3372
3373 extern int inflate_blocks __P((
3374 inflate_blocks_statef *,
3375 z_streamp ,
3376 int)); /* initial return code */
3377
3378 extern void inflate_blocks_reset __P((
3379 inflate_blocks_statef *,
3380 z_streamp ,
3381 uLongf *)); /* check value on output */
3382
3383 extern int inflate_blocks_free __P((
3384 inflate_blocks_statef *,
3385 z_streamp));
3386
3387 extern void inflate_set_dictionary __P((
3388 inflate_blocks_statef *s,
3389 const Bytef *d, /* dictionary */
3390 uInt n)); /* dictionary length */
3391
3392 extern int inflate_blocks_sync_point __P((
3393 inflate_blocks_statef *s));
3394 extern int inflate_addhistory __P((
3395 inflate_blocks_statef *,
3396 z_streamp));
3397
3398 extern int inflate_packet_flush __P((
3399 inflate_blocks_statef *));
3400
3401 /* --- infblock.h */
3402
3403 #ifndef NO_DUMMY_DECL
3404 struct inflate_blocks_state {int dummy;}; /* for buggy compilers */
3405 #endif
3406
3407 typedef enum {
3408 METHOD, /* waiting for method byte */
3409 FLAG, /* waiting for flag byte */
3410 DICT4, /* four dictionary check bytes to go */
3411 DICT3, /* three dictionary check bytes to go */
3412 DICT2, /* two dictionary check bytes to go */
3413 DICT1, /* one dictionary check byte to go */
3414 DICT0, /* waiting for inflateSetDictionary */
3415 BLOCKS, /* decompressing blocks */
3416 CHECK4, /* four check bytes to go */
3417 CHECK3, /* three check bytes to go */
3418 CHECK2, /* two check bytes to go */
3419 CHECK1, /* one check byte to go */
3420 DONE, /* finished check, done */
3421 BAD} /* got an error--stay here */
3422 inflate_mode;
3423
3424 /* inflate private state */
3425 struct internal_state {
3426
3427 /* mode */
3428 inflate_mode mode; /* current inflate mode */
3429
3430 /* mode dependent information */
3431 union {
3432 uInt method; /* if FLAGS, method byte */
3433 struct {
3434 uLong was; /* computed check value */
3435 uLong need; /* stream check value */
3436 } check; /* if CHECK, check values to compare */
3437 uInt marker; /* if BAD, inflateSync's marker bytes count */
3438 } sub; /* submode */
3439
3440 /* mode independent information */
3441 int nowrap; /* flag for no wrapper */
3442 uInt wbits; /* log2(window size) (8..15, defaults to 15) */
3443 inflate_blocks_statef
3444 *blocks; /* current inflate_blocks state */
3445
3446 };
3447
3448
3449 int ZEXPORT inflateReset(z)
3450 z_streamp z;
3451 {
3452 if (z == Z_NULL || z->state == Z_NULL)
3453 return Z_STREAM_ERROR;
3454 z->total_in = z->total_out = 0;
3455 z->msg = Z_NULL;
3456 z->state->mode = z->state->nowrap ? BLOCKS : METHOD;
3457 inflate_blocks_reset(z->state->blocks, z, Z_NULL);
3458 Tracev((stderr, "inflate: reset\n"));
3459 return Z_OK;
3460 }
3461
3462
3463 int ZEXPORT inflateEnd(z)
3464 z_streamp z;
3465 {
3466 if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL)
3467 return Z_STREAM_ERROR;
3468 if (z->state->blocks != Z_NULL)
3469 inflate_blocks_free(z->state->blocks, z);
3470 ZFREE(z, z->state);
3471 z->state = Z_NULL;
3472 Tracev((stderr, "inflate: end\n"));
3473 return Z_OK;
3474 }
3475
3476
3477 int ZEXPORT inflateInit2_(z, w, version, stream_size)
3478 z_streamp z;
3479 int w;
3480 const char *version;
3481 int stream_size;
3482 {
3483 if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
3484 stream_size != sizeof(z_stream))
3485 return Z_VERSION_ERROR;
3486
3487 /* initialize state */
3488 if (z == Z_NULL)
3489 return Z_STREAM_ERROR;
3490 z->msg = Z_NULL;
3491 #ifndef NO_ZCFUNCS
3492 if (z->zalloc == Z_NULL)
3493 {
3494 z->zalloc = zcalloc;
3495 z->opaque = (voidpf)0;
3496 }
3497 if (z->zfree == Z_NULL) z->zfree = zcfree;
3498 #endif
3499 if ((z->state = (struct internal_state FAR *)
3500 ZALLOC(z,1,sizeof(struct internal_state))) == Z_NULL)
3501 return Z_MEM_ERROR;
3502 z->state->blocks = Z_NULL;
3503
3504 /* handle undocumented nowrap option (no zlib header or check) */
3505 z->state->nowrap = 0;
3506 if (w < 0)
3507 {
3508 w = - w;
3509 z->state->nowrap = 1;
3510 }
3511
3512 /* set window size */
3513 if (w < 8 || w > 15)
3514 {
3515 inflateEnd(z);
3516 return Z_STREAM_ERROR;
3517 }
3518 z->state->wbits = (uInt)w;
3519
3520 /* create inflate_blocks state */
3521 if ((z->state->blocks =
3522 inflate_blocks_new(z, z->state->nowrap ? Z_NULL : adler32, (uInt)1 << w))
3523 == Z_NULL)
3524 {
3525 inflateEnd(z);
3526 return Z_MEM_ERROR;
3527 }
3528 Tracev((stderr, "inflate: allocated\n"));
3529
3530 /* reset state */
3531 inflateReset(z);
3532 return Z_OK;
3533 }
3534
3535
3536 int ZEXPORT inflateInit_(z, version, stream_size)
3537 z_streamp z;
3538 const char *version;
3539 int stream_size;
3540 {
3541 return inflateInit2_(z, DEF_WBITS, version, stream_size);
3542 }
3543
3544
3545 #define NEEDBYTE {if(z->avail_in==0)goto empty;r=Z_OK;}
3546 #define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++)
3547
3548 int ZEXPORT inflate(z, f)
3549 z_streamp z;
3550 int f;
3551 {
3552 int r, r2;
3553 uInt b;
3554
3555 if (z == Z_NULL || z->state == Z_NULL || z->next_in == Z_NULL)
3556 return Z_STREAM_ERROR;
3557 r2 = f == Z_FINISH ? Z_BUF_ERROR : Z_OK;
3558 r = Z_BUF_ERROR;
3559 while (1) switch (z->state->mode)
3560 {
3561 case METHOD:
3562 NEEDBYTE
3563 if (((z->state->sub.method = NEXTBYTE) & 0xf) != Z_DEFLATED)
3564 {
3565 z->state->mode = BAD;
3566 z->msg = (char*)"unknown compression method";
3567 z->state->sub.marker = 5; /* can't try inflateSync */
3568 break;
3569 }
3570 if ((z->state->sub.method >> 4) + 8 > z->state->wbits)
3571 {
3572 z->state->mode = BAD;
3573 z->msg = (char*)"invalid window size";
3574 z->state->sub.marker = 5; /* can't try inflateSync */
3575 break;
3576 }
3577 z->state->mode = FLAG;
3578 case FLAG:
3579 NEEDBYTE
3580 b = NEXTBYTE;
3581 if (((z->state->sub.method << 8) + b) % 31)
3582 {
3583 z->state->mode = BAD;
3584 z->msg = (char*)"incorrect header check";
3585 z->state->sub.marker = 5; /* can't try inflateSync */
3586 break;
3587 }
3588 Tracev((stderr, "inflate: zlib header ok\n"));
3589 if (!(b & PRESET_DICT))
3590 {
3591 z->state->mode = BLOCKS;
3592 break;
3593 }
3594 z->state->mode = DICT4;
3595 case DICT4:
3596 NEEDBYTE
3597 z->state->sub.check.need = (uLong)NEXTBYTE << 24;
3598 z->state->mode = DICT3;
3599 case DICT3:
3600 NEEDBYTE
3601 z->state->sub.check.need += (uLong)NEXTBYTE << 16;
3602 z->state->mode = DICT2;
3603 case DICT2:
3604 NEEDBYTE
3605 z->state->sub.check.need += (uLong)NEXTBYTE << 8;
3606 z->state->mode = DICT1;
3607 case DICT1:
3608 NEEDBYTE
3609 z->state->sub.check.need += (uLong)NEXTBYTE;
3610 z->adler = z->state->sub.check.need;
3611 z->state->mode = DICT0;
3612 return Z_NEED_DICT;
3613 case DICT0:
3614 z->state->mode = BAD;
3615 z->msg = (char*)"need dictionary";
3616 z->state->sub.marker = 0; /* can try inflateSync */
3617 return Z_STREAM_ERROR;
3618 case BLOCKS:
3619 r = inflate_blocks(z->state->blocks, z, r);
3620 if (f == Z_PACKET_FLUSH && z->avail_in == 0 && z->avail_out != 0)
3621 r = inflate_packet_flush(z->state->blocks);
3622 if (r == Z_DATA_ERROR)
3623 {
3624 z->state->mode = BAD;
3625 z->state->sub.marker = 0; /* can try inflateSync */
3626 break;
3627 }
3628 if (r == Z_OK)
3629 r = r2;
3630 if (r != Z_STREAM_END)
3631 return r;
3632 r = r2;
3633 inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was);
3634 if (z->state->nowrap)
3635 {
3636 z->state->mode = DONE;
3637 break;
3638 }
3639 z->state->mode = CHECK4;
3640 case CHECK4:
3641 NEEDBYTE
3642 z->state->sub.check.need = (uLong)NEXTBYTE << 24;
3643 z->state->mode = CHECK3;
3644 case CHECK3:
3645 NEEDBYTE
3646 z->state->sub.check.need += (uLong)NEXTBYTE << 16;
3647 z->state->mode = CHECK2;
3648 case CHECK2:
3649 NEEDBYTE
3650 z->state->sub.check.need += (uLong)NEXTBYTE << 8;
3651 z->state->mode = CHECK1;
3652 case CHECK1:
3653 NEEDBYTE
3654 z->state->sub.check.need += (uLong)NEXTBYTE;
3655
3656 if (z->state->sub.check.was != z->state->sub.check.need)
3657 {
3658 z->state->mode = BAD;
3659 z->msg = (char*)"incorrect data check";
3660 z->state->sub.marker = 5; /* can't try inflateSync */
3661 break;
3662 }
3663 Tracev((stderr, "inflate: zlib check ok\n"));
3664 z->state->mode = DONE;
3665 case DONE:
3666 return Z_STREAM_END;
3667 case BAD:
3668 return Z_DATA_ERROR;
3669 default:
3670 return Z_STREAM_ERROR;
3671 }
3672 empty:
3673 if (f != Z_PACKET_FLUSH)
3674 return r;
3675 z->state->mode = BAD;
3676 z->msg = (char *)"need more for packet flush";
3677 z->state->sub.marker = 0;
3678 return Z_DATA_ERROR;
3679 }
3680
3681
3682 int ZEXPORT inflateSetDictionary(z, dictionary, dictLength)
3683 z_streamp z;
3684 const Bytef *dictionary;
3685 uInt dictLength;
3686 {
3687 uInt length = dictLength;
3688
3689 if (z == Z_NULL || z->state == Z_NULL || z->state->mode != DICT0)
3690 return Z_STREAM_ERROR;
3691
3692 if (adler32(1L, dictionary, dictLength) != z->adler) return Z_DATA_ERROR;
3693 z->adler = 1L;
3694
3695 if (length >= ((uInt)1<<z->state->wbits))
3696 {
3697 length = (1<<z->state->wbits)-1;
3698 dictionary += dictLength - length;
3699 }
3700 inflate_set_dictionary(z->state->blocks, dictionary, length);
3701 z->state->mode = BLOCKS;
3702 return Z_OK;
3703 }
3704
3705 /*
3706 * This subroutine adds the data at next_in/avail_in to the output history
3707 * without performing any output. The output buffer must be "caught up";
3708 * i.e. no pending output (hence s->read equals s->write), and the state must
3709 * be BLOCKS (i.e. we should be willing to see the start of a series of
3710 * BLOCKS). On exit, the output will also be caught up, and the checksum
3711 * will have been updated if need be.
3712 */
3713
3714 int inflateIncomp(z)
3715 z_stream *z;
3716 {
3717 if (z->state->mode != BLOCKS)
3718 return Z_DATA_ERROR;
3719 return inflate_addhistory(z->state->blocks, z);
3720 }
3721
3722 int ZEXPORT inflateSync(z)
3723 z_streamp z;
3724 {
3725 uInt n; /* number of bytes to look at */
3726 Bytef *p; /* pointer to bytes */
3727 uInt m; /* number of marker bytes found in a row */
3728 uLong r, w; /* temporaries to save total_in and total_out */
3729
3730 /* set up */
3731 if (z == Z_NULL || z->state == Z_NULL)
3732 return Z_STREAM_ERROR;
3733 if (z->state->mode != BAD)
3734 {
3735 z->state->mode = BAD;
3736 z->state->sub.marker = 0;
3737 }
3738 if ((n = z->avail_in) == 0)
3739 return Z_BUF_ERROR;
3740 p = z->next_in;
3741 m = z->state->sub.marker;
3742
3743 /* search */
3744 while (n && m < 4)
3745 {
3746 static const Byte mark[4] = {0, 0, 0xff, 0xff};
3747 if (*p == mark[m])
3748 m++;
3749 else if (*p)
3750 m = 0;
3751 else
3752 m = 4 - m;
3753 p++, n--;
3754 }
3755
3756 /* restore */
3757 z->total_in += p - z->next_in;
3758 z->next_in = p;
3759 z->avail_in = n;
3760 z->state->sub.marker = m;
3761
3762 /* return no joy or set up to restart on a new block */
3763 if (m != 4)
3764 return Z_DATA_ERROR;
3765 r = z->total_in; w = z->total_out;
3766 inflateReset(z);
3767 z->total_in = r; z->total_out = w;
3768 z->state->mode = BLOCKS;
3769 return Z_OK;
3770 }
3771
3772
3773 /* Returns true if inflate is currently at the end of a block generated
3774 * by Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
3775 * implementation to provide an additional safety check. PPP uses Z_SYNC_FLUSH
3776 * but removes the length bytes of the resulting empty stored block. When
3777 * decompressing, PPP checks that at the end of input packet, inflate is
3778 * waiting for these length bytes.
3779 */
3780 int ZEXPORT inflateSyncPoint(z)
3781 z_streamp z;
3782 {
3783 if (z == Z_NULL || z->state == Z_NULL || z->state->blocks == Z_NULL)
3784 return Z_STREAM_ERROR;
3785 return inflate_blocks_sync_point(z->state->blocks);
3786 }
3787 #undef NEEDBYTE
3788 #undef NEXTBYTE
3789 /* --- inflate.c */
3790
3791 /* +++ infblock.c */
3792
3793 /* infblock.c -- interpret and process block types to last block
3794 * Copyright (C) 1995-2002 Mark Adler
3795 * For conditions of distribution and use, see copyright notice in zlib.h
3796 */
3797
3798 /* #include "zutil.h" */
3799 /* #include "infblock.h" */
3800
3801 /* +++ inftrees.h */
3802
3803 /* inftrees.h -- header to use inftrees.c
3804 * Copyright (C) 1995-2002 Mark Adler
3805 * For conditions of distribution and use, see copyright notice in zlib.h
3806 */
3807
3808 /* WARNING: this file should *not* be used by applications. It is
3809 part of the implementation of the compression library and is
3810 subject to change. Applications should only use zlib.h.
3811 */
3812
3813 /* Huffman code lookup table entry--this entry is four bytes for machines
3814 that have 16-bit pointers (e.g. PC's in the small or medium model). */
3815
3816 typedef struct inflate_huft_s FAR inflate_huft;
3817
3818 struct inflate_huft_s {
3819 union {
3820 struct {
3821 Byte Exop; /* number of extra bits or operation */
3822 Byte Bits; /* number of bits in this code or subcode */
3823 } what;
3824 uInt pad; /* pad structure to a power of 2 (4 bytes for */
3825 } word; /* 16-bit, 8 bytes for 32-bit int's) */
3826 uInt base; /* literal, length base, distance base,
3827 or table offset */
3828 };
3829
3830 /* Maximum size of dynamic tree. The maximum found in a long but non-
3831 exhaustive search was 1004 huft structures (850 for length/literals
3832 and 154 for distances, the latter actually the result of an
3833 exhaustive search). The actual maximum is not known, but the
3834 value below is more than safe. */
3835 #define MANY 1440
3836
3837 extern int inflate_trees_bits __P((
3838 uIntf *, /* 19 code lengths */
3839 uIntf *, /* bits tree desired/actual depth */
3840 inflate_huft * FAR *, /* bits tree result */
3841 inflate_huft *, /* space for trees */
3842 z_streamp)); /* for messages */
3843
3844 extern int inflate_trees_dynamic __P((
3845 uInt, /* number of literal/length codes */
3846 uInt, /* number of distance codes */
3847 uIntf *, /* that many (total) code lengths */
3848 uIntf *, /* literal desired/actual bit depth */
3849 uIntf *, /* distance desired/actual bit depth */
3850 inflate_huft * FAR *, /* literal/length tree result */
3851 inflate_huft * FAR *, /* distance tree result */
3852 inflate_huft *, /* space for trees */
3853 z_streamp)); /* for messages */
3854
3855 extern int inflate_trees_fixed __P((
3856 uIntf *, /* literal desired/actual bit depth */
3857 uIntf *, /* distance desired/actual bit depth */
3858 inflate_huft * FAR *, /* literal/length tree result */
3859 inflate_huft * FAR *, /* distance tree result */
3860 z_streamp)); /* for memory allocation */
3861 /* --- inftrees.h */
3862
3863 /* +++ infcodes.h */
3864
3865 /* infcodes.h -- header to use infcodes.c
3866 * Copyright (C) 1995-2002 Mark Adler
3867 * For conditions of distribution and use, see copyright notice in zlib.h
3868 */
3869
3870 /* WARNING: this file should *not* be used by applications. It is
3871 part of the implementation of the compression library and is
3872 subject to change. Applications should only use zlib.h.
3873 */
3874
3875 struct inflate_codes_state;
3876 typedef struct inflate_codes_state FAR inflate_codes_statef;
3877
3878 extern inflate_codes_statef *inflate_codes_new __P((
3879 uInt, uInt,
3880 inflate_huft *, inflate_huft *,
3881 z_streamp ));
3882
3883 extern int inflate_codes __P((
3884 inflate_blocks_statef *,
3885 z_streamp ,
3886 int));
3887
3888 extern void inflate_codes_free __P((
3889 inflate_codes_statef *,
3890 z_streamp ));
3891
3892 /* --- infcodes.h */
3893
3894 /* +++ infutil.h */
3895
3896 /* infutil.h -- types and macros common to blocks and codes
3897 * Copyright (C) 1995-2002 Mark Adler
3898 * For conditions of distribution and use, see copyright notice in zlib.h
3899 */
3900
3901 /* WARNING: this file should *not* be used by applications. It is
3902 part of the implementation of the compression library and is
3903 subject to change. Applications should only use zlib.h.
3904 */
3905
3906 #ifndef _INFUTIL_H
3907 #define _INFUTIL_H
3908
3909 typedef enum {
3910 TYPE, /* get type bits (3, including end bit) */
3911 LENS, /* get lengths for stored */
3912 STORED, /* processing stored block */
3913 TABLE, /* get table lengths */
3914 BTREE, /* get bit lengths tree for a dynamic block */
3915 DTREE, /* get length, distance trees for a dynamic block */
3916 CODES, /* processing fixed or dynamic block */
3917 DRY, /* output remaining window bytes */
3918 DONEB, /* finished last block, done */
3919 BADB} /* got a data error--stuck here */
3920 inflate_block_mode;
3921
3922 /* inflate blocks semi-private state */
3923 struct inflate_blocks_state {
3924
3925 /* mode */
3926 inflate_block_mode mode; /* current inflate_block mode */
3927
3928 /* mode dependent information */
3929 union {
3930 uInt left; /* if STORED, bytes left to copy */
3931 struct {
3932 uInt table; /* table lengths (14 bits) */
3933 uInt index; /* index into blens (or border) */
3934 uIntf *blens; /* bit lengths of codes */
3935 uInt bb; /* bit length tree depth */
3936 inflate_huft *tb; /* bit length decoding tree */
3937 } trees; /* if DTREE, decoding info for trees */
3938 struct {
3939 inflate_codes_statef
3940 *codes;
3941 } decode; /* if CODES, current state */
3942 } sub; /* submode */
3943 uInt last; /* true if this block is the last block */
3944
3945 /* mode independent information */
3946 uInt bitk; /* bits in bit buffer */
3947 uLong bitb; /* bit buffer */
3948 inflate_huft *hufts; /* single malloc for tree space */
3949 Bytef *window; /* sliding window */
3950 Bytef *end; /* one byte after sliding window */
3951 Bytef *read; /* window read pointer */
3952 Bytef *write; /* window write pointer */
3953 check_func checkfn; /* check function */
3954 uLong check; /* check on output */
3955
3956 };
3957
3958
3959 /* defines for inflate input/output */
3960 /* update pointers and return */
3961 #define UPDBITS {s->bitb=b;s->bitk=k;}
3962 #define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;}
3963 #define UPDOUT {s->write=q;}
3964 #define UPDATE {UPDBITS UPDIN UPDOUT}
3965 #define LEAVE {UPDATE return inflate_flush(s,z,r);}
3966 /* get bytes and bits */
3967 #define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;}
3968 #define NEEDBYTE {if(n)r=Z_OK;else LEAVE}
3969 #define NEXTBYTE (n--,*p++)
3970 #define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}}
3971 #define DUMPBITS(j) {b>>=(j);k-=(j);}
3972 /* output bytes */
3973 #define WAVAIL (uInt)(q<s->read?s->read-q-1:s->end-q)
3974 #define LOADOUT {q=s->write;m=(uInt)WAVAIL;}
3975 #define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}}
3976 #define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT}
3977 #define NEEDOUT {if(m==0){WRAP if(m==0){FLUSH WRAP if(m==0) LEAVE}}r=Z_OK;}
3978 #define OUTBYTE(a) {*q++=(Byte)(a);m--;}
3979 /* load local pointers */
3980 #define LOAD {LOADIN LOADOUT}
3981
3982 /* masks for lower bits (size given to avoid silly warnings with Visual C++) */
3983 extern uInt inflate_mask[17];
3984
3985 /* copy as much as possible from the sliding window to the output area */
3986 extern int inflate_flush __P((
3987 inflate_blocks_statef *,
3988 z_streamp ,
3989 int));
3990
3991 #ifndef NO_DUMMY_DECL
3992 struct internal_state {int dummy;}; /* for buggy compilers */
3993 #endif
3994
3995 #endif
3996 /* --- infutil.h */
3997
3998 #ifndef NO_DUMMY_DECL
3999 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
4000 #endif
4001
4002 /* simplify the use of the inflate_huft type with some defines */
4003 #define exop word.what.Exop
4004 #define bits word.what.Bits
4005
4006 /* Table for deflate from PKZIP's appnote.txt. */
4007 local const uInt border[] = { /* Order of the bit length code lengths */
4008 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
4009
4010 /*
4011 Notes beyond the 1.93a appnote.txt:
4012
4013 1. Distance pointers never point before the beginning of the output
4014 stream.
4015 2. Distance pointers can point back across blocks, up to 32k away.
4016 3. There is an implied maximum of 7 bits for the bit length table and
4017 15 bits for the actual data.
4018 4. If only one code exists, then it is encoded using one bit. (Zero
4019 would be more efficient, but perhaps a little confusing.) If two
4020 codes exist, they are coded using one bit each (0 and 1).
4021 5. There is no way of sending zero distance codes--a dummy must be
4022 sent if there are none. (History: a pre 2.0 version of PKZIP would
4023 store blocks with no distance codes, but this was discovered to be
4024 too harsh a criterion.) Valid only for 1.93a. 2.04c does allow
4025 zero distance codes, which is sent as one code of zero bits in
4026 length.
4027 6. There are up to 286 literal/length codes. Code 256 represents the
4028 end-of-block. Note however that the static length tree defines
4029 288 codes just to fill out the Huffman codes. Codes 286 and 287
4030 cannot be used though, since there is no length base or extra bits
4031 defined for them. Similarily, there are up to 30 distance codes.
4032 However, static trees define 32 codes (all 5 bits) to fill out the
4033 Huffman codes, but the last two had better not show up in the data.
4034 7. Unzip can check dynamic Huffman blocks for complete code sets.
4035 The exception is that a single code would not be complete (see #4).
4036 8. The five bits following the block type is really the number of
4037 literal codes sent minus 257.
4038 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
4039 (1+6+6). Therefore, to output three times the length, you output
4040 three codes (1+1+1), whereas to output four times the same length,
4041 you only need two codes (1+3). Hmm.
4042 10. In the tree reconstruction algorithm, Code = Code + Increment
4043 only if BitLength(i) is not zero. (Pretty obvious.)
4044 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19)
4045 12. Note: length code 284 can represent 227-258, but length code 285
4046 really is 258. The last length deserves its own, short code
4047 since it gets used a lot in very redundant files. The length
4048 258 is special since 258 - 3 (the min match length) is 255.
4049 13. The literal/length and distance code bit lengths are read as a
4050 single stream of lengths. It is possible (and advantageous) for
4051 a repeat code (16, 17, or 18) to go across the boundary between
4052 the two sets of lengths.
4053 */
4054
4055
4056 void inflate_blocks_reset(s, z, c)
4057 inflate_blocks_statef *s;
4058 z_streamp z;
4059 uLongf *c;
4060 {
4061 if (c != Z_NULL)
4062 *c = s->check;
4063 if (s->mode == BTREE || s->mode == DTREE)
4064 ZFREE(z, s->sub.trees.blens);
4065 if (s->mode == CODES)
4066 inflate_codes_free(s->sub.decode.codes, z);
4067 s->mode = TYPE;
4068 s->bitk = 0;
4069 s->bitb = 0;
4070 s->read = s->write = s->window;
4071 if (s->checkfn != Z_NULL)
4072 z->adler = s->check = (*s->checkfn)(0L, (const Bytef *)Z_NULL, 0);
4073 Tracev((stderr, "inflate: blocks reset\n"));
4074 }
4075
4076
4077 inflate_blocks_statef *inflate_blocks_new(z, c, w)
4078 z_streamp z;
4079 check_func c;
4080 uInt w;
4081 {
4082 inflate_blocks_statef *s;
4083
4084 if ((s = (inflate_blocks_statef *)ZALLOC
4085 (z,1,sizeof(struct inflate_blocks_state))) == Z_NULL)
4086 return s;
4087 if ((s->hufts =
4088 (inflate_huft *)ZALLOC(z, sizeof(inflate_huft), MANY)) == Z_NULL)
4089 {
4090 ZFREE(z, s);
4091 return Z_NULL;
4092 }
4093 if ((s->window = (Bytef *)ZALLOC(z, 1, w)) == Z_NULL)
4094 {
4095 ZFREE(z, s->hufts);
4096 ZFREE(z, s);
4097 return Z_NULL;
4098 }
4099 s->end = s->window + w;
4100 s->checkfn = c;
4101 s->mode = TYPE;
4102 Tracev((stderr, "inflate: blocks allocated\n"));
4103 inflate_blocks_reset(s, z, Z_NULL);
4104 return s;
4105 }
4106
4107
4108 int inflate_blocks(s, z, r)
4109 inflate_blocks_statef *s;
4110 z_streamp z;
4111 int r;
4112 {
4113 uInt t; /* temporary storage */
4114 uLong b; /* bit buffer */
4115 uInt k; /* bits in bit buffer */
4116 Bytef *p; /* input data pointer */
4117 uInt n; /* bytes available there */
4118 Bytef *q; /* output window write pointer */
4119 uInt m; /* bytes to end of window or read pointer */
4120
4121 /* copy input/output information to locals (UPDATE macro restores) */
4122 LOAD
4123
4124 /* process input based on current state */
4125 while (1) switch (s->mode)
4126 {
4127 case TYPE:
4128 NEEDBITS(3)
4129 t = (uInt)b & 7;
4130 s->last = t & 1;
4131 switch (t >> 1)
4132 {
4133 case 0: /* stored */
4134 Tracev((stderr, "inflate: stored block%s\n",
4135 s->last ? " (last)" : ""));
4136 DUMPBITS(3)
4137 t = k & 7; /* go to byte boundary */
4138 DUMPBITS(t)
4139 s->mode = LENS; /* get length of stored block */
4140 break;
4141 case 1: /* fixed */
4142 Tracev((stderr, "inflate: fixed codes block%s\n",
4143 s->last ? " (last)" : ""));
4144 {
4145 uInt bl, bd;
4146 inflate_huft *tl, *td;
4147
4148 inflate_trees_fixed(&bl, &bd, &tl, &td, z);
4149 s->sub.decode.codes = inflate_codes_new(bl, bd, tl, td, z);
4150 if (s->sub.decode.codes == Z_NULL)
4151 {
4152 r = Z_MEM_ERROR;
4153 LEAVE
4154 }
4155 }
4156 DUMPBITS(3)
4157 s->mode = CODES;
4158 break;
4159 case 2: /* dynamic */
4160 Tracev((stderr, "inflate: dynamic codes block%s\n",
4161 s->last ? " (last)" : ""));
4162 DUMPBITS(3)
4163 s->mode = TABLE;
4164 break;
4165 case 3: /* illegal */
4166 DUMPBITS(3)
4167 s->mode = BADB;
4168 z->msg = (char*)"invalid block type";
4169 r = Z_DATA_ERROR;
4170 LEAVE
4171 }
4172 break;
4173 case LENS:
4174 NEEDBITS(32)
4175 if ((((~b) >> 16) & 0xffff) != (b & 0xffff))
4176 {
4177 s->mode = BADB;
4178 z->msg = (char*)"invalid stored block lengths";
4179 r = Z_DATA_ERROR;
4180 LEAVE
4181 }
4182 s->sub.left = (uInt)b & 0xffff;
4183 b = k = 0; /* dump bits */
4184 Tracev((stderr, "inflate: stored length %u\n", s->sub.left));
4185 s->mode = s->sub.left ? STORED : (s->last ? DRY : TYPE);
4186 break;
4187 case STORED:
4188 if (n == 0)
4189 LEAVE
4190 NEEDOUT
4191 t = s->sub.left;
4192 if (t > n) t = n;
4193 if (t > m) t = m;
4194 zmemcpy(q, p, t);
4195 p += t; n -= t;
4196 q += t; m -= t;
4197 if ((s->sub.left -= t) != 0)
4198 break;
4199 Tracev((stderr, "inflate: stored end, %lu total out\n",
4200 z->total_out + (q >= s->read ? q - s->read :
4201 (s->end - s->read) + (q - s->window))));
4202 s->mode = s->last ? DRY : TYPE;
4203 break;
4204 case TABLE:
4205 NEEDBITS(14)
4206 s->sub.trees.table = t = (uInt)b & 0x3fff;
4207 #ifndef PKZIP_BUG_WORKAROUND
4208 if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29)
4209 {
4210 s->mode = BADB;
4211 z->msg = (char*)"too many length or distance symbols";
4212 r = Z_DATA_ERROR;
4213 LEAVE
4214 }
4215 #endif
4216 t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
4217 if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL)
4218 {
4219 r = Z_MEM_ERROR;
4220 LEAVE
4221 }
4222 DUMPBITS(14)
4223 s->sub.trees.index = 0;
4224 Tracev((stderr, "inflate: table sizes ok\n"));
4225 s->mode = BTREE;
4226 case BTREE:
4227 while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10))
4228 {
4229 NEEDBITS(3)
4230 s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7;
4231 DUMPBITS(3)
4232 }
4233 while (s->sub.trees.index < 19)
4234 s->sub.trees.blens[border[s->sub.trees.index++]] = 0;
4235 s->sub.trees.bb = 7;
4236 t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb,
4237 &s->sub.trees.tb, s->hufts, z);
4238 if (t != Z_OK)
4239 {
4240 r = t;
4241 if (r == Z_DATA_ERROR)
4242 {
4243 ZFREE(z, s->sub.trees.blens);
4244 s->mode = BADB;
4245 }
4246 LEAVE
4247 }
4248 s->sub.trees.index = 0;
4249 Tracev((stderr, "inflate: bits tree ok\n"));
4250 s->mode = DTREE;
4251 case DTREE:
4252 while (t = s->sub.trees.table,
4253 s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f))
4254 {
4255 inflate_huft *h;
4256 uInt i, j, c;
4257
4258 t = s->sub.trees.bb;
4259 NEEDBITS(t)
4260 h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]);
4261 t = h->bits;
4262 c = h->base;
4263 if (c < 16)
4264 {
4265 DUMPBITS(t)
4266 s->sub.trees.blens[s->sub.trees.index++] = c;
4267 }
4268 else /* c == 16..18 */
4269 {
4270 i = c == 18 ? 7 : c - 14;
4271 j = c == 18 ? 11 : 3;
4272 NEEDBITS(t + i)
4273 DUMPBITS(t)
4274 j += (uInt)b & inflate_mask[i];
4275 DUMPBITS(i)
4276 i = s->sub.trees.index;
4277 t = s->sub.trees.table;
4278 if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) ||
4279 (c == 16 && i < 1))
4280 {
4281 ZFREE(z, s->sub.trees.blens);
4282 s->mode = BADB;
4283 z->msg = (char*)"invalid bit length repeat";
4284 r = Z_DATA_ERROR;
4285 LEAVE
4286 }
4287 c = c == 16 ? s->sub.trees.blens[i - 1] : 0;
4288 do {
4289 s->sub.trees.blens[i++] = c;
4290 } while (--j);
4291 s->sub.trees.index = i;
4292 }
4293 }
4294 s->sub.trees.tb = Z_NULL;
4295 {
4296 uInt bl, bd;
4297 inflate_huft *tl, *td;
4298 inflate_codes_statef *c;
4299
4300 bl = 9; /* must be <= 9 for lookahead assumptions */
4301 bd = 6; /* must be <= 9 for lookahead assumptions */
4302 t = s->sub.trees.table;
4303 t = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f),
4304 s->sub.trees.blens, &bl, &bd, &tl, &td,
4305 s->hufts, z);
4306 if (t != Z_OK)
4307 {
4308 if (t == (uInt)Z_DATA_ERROR)
4309 {
4310 ZFREE(z, s->sub.trees.blens);
4311 s->mode = BADB;
4312 }
4313 r = t;
4314 LEAVE
4315 }
4316 Tracev((stderr, "inflate: trees ok\n"));
4317 if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL)
4318 {
4319 r = Z_MEM_ERROR;
4320 LEAVE
4321 }
4322 s->sub.decode.codes = c;
4323 }
4324 ZFREE(z, s->sub.trees.blens);
4325 s->mode = CODES;
4326 case CODES:
4327 UPDATE
4328 if ((r = inflate_codes(s, z, r)) != Z_STREAM_END)
4329 return inflate_flush(s, z, r);
4330 r = Z_OK;
4331 inflate_codes_free(s->sub.decode.codes, z);
4332 LOAD
4333 Tracev((stderr, "inflate: codes end, %lu total out\n",
4334 z->total_out + (q >= s->read ? q - s->read :
4335 (s->end - s->read) + (q - s->window))));
4336 if (!s->last)
4337 {
4338 s->mode = TYPE;
4339 break;
4340 }
4341 s->mode = DRY;
4342 case DRY:
4343 FLUSH
4344 if (s->read != s->write)
4345 LEAVE
4346 s->mode = DONEB;
4347 case DONEB:
4348 r = Z_STREAM_END;
4349 LEAVE
4350 case BADB:
4351 r = Z_DATA_ERROR;
4352 LEAVE
4353 default:
4354 r = Z_STREAM_ERROR;
4355 LEAVE
4356 }
4357 }
4358
4359
4360 int inflate_blocks_free(s, z)
4361 inflate_blocks_statef *s;
4362 z_streamp z;
4363 {
4364 inflate_blocks_reset(s, z, Z_NULL);
4365 ZFREE(z, s->window);
4366 ZFREE(z, s->hufts);
4367 ZFREE(z, s);
4368 Tracev((stderr, "inflate: blocks freed\n"));
4369 return Z_OK;
4370 }
4371
4372
4373 void inflate_set_dictionary(s, d, n)
4374 inflate_blocks_statef *s;
4375 const Bytef *d;
4376 uInt n;
4377 {
4378 zmemcpy(s->window, d, n);
4379 s->read = s->write = s->window + n;
4380 }
4381
4382 /*
4383 * This subroutine adds the data at next_in/avail_in to the output history
4384 * without performing any output. The output buffer must be "caught up";
4385 * i.e. no pending output (hence s->read equals s->write), and the state must
4386 * be BLOCKS (i.e. we should be willing to see the start of a series of
4387 * BLOCKS). On exit, the output will also be caught up, and the checksum
4388 * will have been updated if need be.
4389 */
4390 int inflate_addhistory(s, z)
4391 inflate_blocks_statef *s;
4392 z_stream *z;
4393 {
4394 uLong b; /* bit buffer */ /* NOT USED HERE */
4395 uInt k; /* bits in bit buffer */ /* NOT USED HERE */
4396 uInt t; /* temporary storage */
4397 Bytef *p; /* input data pointer */
4398 uInt n; /* bytes available there */
4399 Bytef *q; /* output window write pointer */
4400 uInt m; /* bytes to end of window or read pointer */
4401
4402 if (s->read != s->write)
4403 return Z_STREAM_ERROR;
4404 if (s->mode != TYPE)
4405 return Z_DATA_ERROR;
4406
4407 /* we're ready to rock */
4408 LOAD
4409 /* while there is input ready, copy to output buffer, moving
4410 * pointers as needed.
4411 */
4412 while (n) {
4413 t = n; /* how many to do */
4414 /* is there room until end of buffer? */
4415 if (t > m) t = m;
4416 /* update check information */
4417 if (s->checkfn != Z_NULL)
4418 s->check = (*s->checkfn)(s->check, q, t);
4419 zmemcpy(q, p, t);
4420 q += t;
4421 p += t;
4422 n -= t;
4423 z->total_out += t;
4424 s->read = q; /* drag read pointer forward */
4425 /* WWRAP */ /* expand WWRAP macro by hand to handle s->read */
4426 if (q == s->end) {
4427 s->read = q = s->window;
4428 m = WAVAIL;
4429 }
4430 }
4431 UPDATE
4432 return Z_OK;
4433 }
4434
4435
4436 /*
4437 * At the end of a Deflate-compressed PPP packet, we expect to have seen
4438 * a `stored' block type value but not the (zero) length bytes.
4439 */
4440 int inflate_packet_flush(s)
4441 inflate_blocks_statef *s;
4442 {
4443 if (s->mode != LENS)
4444 return Z_DATA_ERROR;
4445 s->mode = TYPE;
4446 return Z_OK;
4447 }
4448
4449 /* Returns true if inflate is currently at the end of a block generated
4450 * by Z_SYNC_FLUSH or Z_FULL_FLUSH.
4451 * IN assertion: s != Z_NULL
4452 */
4453 int inflate_blocks_sync_point(s)
4454 inflate_blocks_statef *s;
4455 {
4456 return s->mode == LENS;
4457 }
4458 /* --- infblock.c */
4459
4460
4461 /* +++ inftrees.c */
4462
4463 /* inftrees.c -- generate Huffman trees for efficient decoding
4464 * Copyright (C) 1995-2002 Mark Adler
4465 * For conditions of distribution and use, see copyright notice in zlib.h
4466 */
4467
4468 /* #include "zutil.h" */
4469 /* #include "inftrees.h" */
4470
4471 #if !defined(BUILDFIXED) && !defined(STDC)
4472 # define BUILDFIXED /* non ANSI compilers may not accept inffixed.h */
4473 #endif
4474
4475 const char inflate_copyright[] =
4476 " inflate 1.1.4 Copyright 1995-2002 Mark Adler ";
4477 /*
4478 If you use the zlib library in a product, an acknowledgment is welcome
4479 in the documentation of your product. If for some reason you cannot
4480 include such an acknowledgment, I would appreciate that you keep this
4481 copyright string in the executable of your product.
4482 */
4483
4484 #ifndef NO_DUMMY_DECL
4485 struct internal_state {int dummy;}; /* for buggy compilers */
4486 #endif
4487
4488 /* simplify the use of the inflate_huft type with some defines */
4489 #define exop word.what.Exop
4490 #define bits word.what.Bits
4491
4492
4493 local int huft_build __P((
4494 uIntf *, /* code lengths in bits */
4495 uInt, /* number of codes */
4496 uInt, /* number of "simple" codes */
4497 const uIntf *, /* list of base values for non-simple codes */
4498 const uIntf *, /* list of extra bits for non-simple codes */
4499 inflate_huft * FAR*,/* result: starting table */
4500 uIntf *, /* maximum lookup bits (returns actual) */
4501 inflate_huft *, /* space for trees */
4502 uInt *, /* hufts used in space */
4503 uIntf * )); /* space for values */
4504
4505 /* Tables for deflate from PKZIP's appnote.txt. */
4506 local const uInt cplens[31] = { /* Copy lengths for literal codes 257..285 */
4507 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
4508 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
4509 /* see note #13 above about 258 */
4510 local const uInt cplext[31] = { /* Extra bits for literal codes 257..285 */
4511 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
4512 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 112, 112}; /* 112==invalid */
4513 local const uInt cpdist[30] = { /* Copy offsets for distance codes 0..29 */
4514 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
4515 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
4516 8193, 12289, 16385, 24577};
4517 local const uInt cpdext[30] = { /* Extra bits for distance codes */
4518 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
4519 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
4520 12, 12, 13, 13};
4521
4522 /*
4523 Huffman code decoding is performed using a multi-level table lookup.
4524 The fastest way to decode is to simply build a lookup table whose
4525 size is determined by the longest code. However, the time it takes
4526 to build this table can also be a factor if the data being decoded
4527 is not very long. The most common codes are necessarily the
4528 shortest codes, so those codes dominate the decoding time, and hence
4529 the speed. The idea is you can have a shorter table that decodes the
4530 shorter, more probable codes, and then point to subsidiary tables for
4531 the longer codes. The time it costs to decode the longer codes is
4532 then traded against the time it takes to make longer tables.
4533
4534 This results of this trade are in the variables lbits and dbits
4535 below. lbits is the number of bits the first level table for literal/
4536 length codes can decode in one step, and dbits is the same thing for
4537 the distance codes. Subsequent tables are also less than or equal to
4538 those sizes. These values may be adjusted either when all of the
4539 codes are shorter than that, in which case the longest code length in
4540 bits is used, or when the shortest code is *longer* than the requested
4541 table size, in which case the length of the shortest code in bits is
4542 used.
4543
4544 There are two different values for the two tables, since they code a
4545 different number of possibilities each. The literal/length table
4546 codes 286 possible values, or in a flat code, a little over eight
4547 bits. The distance table codes 30 possible values, or a little less
4548 than five bits, flat. The optimum values for speed end up being
4549 about one bit more than those, so lbits is 8+1 and dbits is 5+1.
4550 The optimum values may differ though from machine to machine, and
4551 possibly even between compilers. Your mileage may vary.
4552 */
4553
4554
4555 /* If BMAX needs to be larger than 16, then h and x[] should be uLong. */
4556 #define BMAX 15 /* maximum bit length of any code */
4557
4558 local int huft_build(b, n, s, d, e, t, m, hp, hn, v)
4559 uIntf *b; /* code lengths in bits (all assumed <= BMAX) */
4560 uInt n; /* number of codes (assumed <= 288) */
4561 uInt s; /* number of simple-valued codes (0..s-1) */
4562 const uIntf *d; /* list of base values for non-simple codes */
4563 const uIntf *e; /* list of extra bits for non-simple codes */
4564 inflate_huft * FAR *t; /* result: starting table */
4565 uIntf *m; /* maximum lookup bits, returns actual */
4566 inflate_huft *hp; /* space for trees */
4567 uInt *hn; /* hufts used in space */
4568 uIntf *v; /* working area: values in order of bit length */
4569 /* Given a list of code lengths and a maximum table size, make a set of
4570 tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR
4571 if the given code set is incomplete (the tables are still built in this
4572 case), or Z_DATA_ERROR if the input is invalid. */
4573 {
4574
4575 uInt a; /* counter for codes of length k */
4576 uInt c[BMAX+1]; /* bit length count table */
4577 uInt f; /* i repeats in table every f entries */
4578 int g; /* maximum code length */
4579 int h; /* table level */
4580 uInt i; /* counter, current code */
4581 uInt j; /* counter */
4582 int k; /* number of bits in current code */
4583 int l; /* bits per table (returned in m) */
4584 uInt mask; /* (1 << w) - 1, to avoid cc -O bug on HP */
4585 uIntf *p; /* pointer into c[], b[], or v[] */
4586 inflate_huft *q; /* points to current table */
4587 struct inflate_huft_s r; /* table entry for structure assignment */
4588 inflate_huft *u[BMAX]; /* table stack */
4589 int w; /* bits before this table == (l * h) */
4590 uInt x[BMAX+1]; /* bit offsets, then code stack */
4591 uIntf *xp; /* pointer into x */
4592 int y; /* number of dummy codes added */
4593 uInt z; /* number of entries in current table */
4594
4595
4596 /* Generate counts for each bit length */
4597 p = c;
4598 #define C0 *p++ = 0;
4599 #define C2 C0 C0 C0 C0
4600 #define C4 C2 C2 C2 C2
4601 C4 /* clear c[]--assume BMAX+1 is 16 */
4602 p = b; i = n;
4603 do {
4604 c[*p++]++; /* assume all entries <= BMAX */
4605 } while (--i);
4606 if (c[0] == n) /* null input--all zero length codes */
4607 {
4608 *t = (inflate_huft *)Z_NULL;
4609 *m = 0;
4610 return Z_OK;
4611 }
4612
4613
4614 /* Find minimum and maximum length, bound *m by those */
4615 l = *m;
4616 for (j = 1; j <= BMAX; j++)
4617 if (c[j])
4618 break;
4619 k = j; /* minimum code length */
4620 if ((uInt)l < j)
4621 l = j;
4622 for (i = BMAX; i; i--)
4623 if (c[i])
4624 break;
4625 g = i; /* maximum code length */
4626 if ((uInt)l > i)
4627 l = i;
4628 *m = l;
4629
4630
4631 /* Adjust last length count to fill out codes, if needed */
4632 for (y = 1 << j; j < i; j++, y <<= 1)
4633 if ((y -= c[j]) < 0)
4634 return Z_DATA_ERROR;
4635 if ((y -= c[i]) < 0)
4636 return Z_DATA_ERROR;
4637 c[i] += y;
4638
4639
4640 /* Generate starting offsets into the value table for each length */
4641 x[1] = j = 0;
4642 p = c + 1; xp = x + 2;
4643 while (--i) { /* note that i == g from above */
4644 *xp++ = (j += *p++);
4645 }
4646
4647
4648 /* Make a table of values in order of bit lengths */
4649 p = b; i = 0;
4650 do {
4651 if ((j = *p++) != 0)
4652 v[x[j]++] = i;
4653 } while (++i < n);
4654 n = x[g]; /* set n to length of v */
4655
4656
4657 /* Generate the Huffman codes and for each, make the table entries */
4658 x[0] = i = 0; /* first Huffman code is zero */
4659 p = v; /* grab values in bit order */
4660 h = -1; /* no tables yet--level -1 */
4661 w = -l; /* bits decoded == (l * h) */
4662 u[0] = (inflate_huft *)Z_NULL; /* just to keep compilers happy */
4663 q = (inflate_huft *)Z_NULL; /* ditto */
4664 z = 0; /* ditto */
4665
4666 /* go through the bit lengths (k already is bits in shortest code) */
4667 for (; k <= g; k++)
4668 {
4669 a = c[k];
4670 while (a--)
4671 {
4672 /* here i is the Huffman code of length k bits for value *p */
4673 /* make tables up to required level */
4674 while (k > w + l)
4675 {
4676 h++;
4677 w += l; /* previous table always l bits */
4678
4679 /* compute minimum size table less than or equal to l bits */
4680 z = g - w;
4681 z = z > (uInt)l ? l : z; /* table size upper limit */
4682 if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */
4683 { /* too few codes for k-w bit table */
4684 f -= a + 1; /* deduct codes from patterns left */
4685 xp = c + k;
4686 if (j < z)
4687 while (++j < z) /* try smaller tables up to z bits */
4688 {
4689 if ((f <<= 1) <= *++xp)
4690 break; /* enough codes to use up j bits */
4691 f -= *xp; /* else deduct codes from patterns */
4692 }
4693 }
4694 z = 1 << j; /* table entries for j-bit table */
4695
4696 /* allocate new table */
4697 if (*hn + z > MANY) /* (note: doesn't matter for fixed) */
4698 return Z_DATA_ERROR; /* overflow of MANY */
4699 u[h] = q = hp + *hn;
4700 *hn += z;
4701
4702 /* connect to last table, if there is one */
4703 if (h)
4704 {
4705 x[h] = i; /* save pattern for backing up */
4706 r.bits = (Byte)l; /* bits to dump before this table */
4707 r.exop = (Byte)j; /* bits in this table */
4708 j = i >> (w - l);
4709 r.base = (uInt)(q - u[h-1] - j); /* offset to this table */
4710 u[h-1][j] = r; /* connect to last table */
4711 }
4712 else
4713 *t = q; /* first table is returned result */
4714 }
4715
4716 /* set up table entry in r */
4717 r.bits = (Byte)(k - w);
4718 if (p >= v + n)
4719 r.exop = 128 + 64; /* out of values--invalid code */
4720 else if (*p < s)
4721 {
4722 r.exop = (Byte)(*p < 256 ? 0 : 32 + 64); /* 256 is end-of-block */
4723 r.base = *p++; /* simple code is just the value */
4724 }
4725 else
4726 {
4727 r.exop = (Byte)(e[*p - s] + 16 + 64);/* non-simple--look up in lists */
4728 r.base = d[*p++ - s];
4729 }
4730
4731 /* fill code-like entries with r */
4732 f = 1 << (k - w);
4733 for (j = i >> w; j < z; j += f)
4734 q[j] = r;
4735
4736 /* backwards increment the k-bit code i */
4737 for (j = 1 << (k - 1); i & j; j >>= 1)
4738 i ^= j;
4739 i ^= j;
4740
4741 /* backup over finished tables */
4742 mask = (1 << w) - 1; /* needed on HP, cc -O bug */
4743 while ((i & mask) != x[h])
4744 {
4745 h--; /* don't need to update q */
4746 w -= l;
4747 mask = (1 << w) - 1;
4748 }
4749 }
4750 }
4751
4752
4753 /* Return Z_BUF_ERROR if we were given an incomplete table */
4754 return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK;
4755 }
4756
4757
4758 int inflate_trees_bits(c, bb, tb, hp, z)
4759 uIntf *c; /* 19 code lengths */
4760 uIntf *bb; /* bits tree desired/actual depth */
4761 inflate_huft * FAR *tb; /* bits tree result */
4762 inflate_huft *hp; /* space for trees */
4763 z_streamp z; /* for messages */
4764 {
4765 int r;
4766 uInt hn = 0; /* hufts used in space */
4767 uIntf *v; /* work area for huft_build */
4768
4769 if ((v = (uIntf*)ZALLOC(z, 19, sizeof(uInt))) == Z_NULL)
4770 return Z_MEM_ERROR;
4771 r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL,
4772 tb, bb, hp, &hn, v);
4773 if (r == Z_DATA_ERROR)
4774 z->msg = (char*)"oversubscribed dynamic bit lengths tree";
4775 else if (r == Z_BUF_ERROR || *bb == 0)
4776 {
4777 z->msg = (char*)"incomplete dynamic bit lengths tree";
4778 r = Z_DATA_ERROR;
4779 }
4780 ZFREE(z, v);
4781 return r;
4782 }
4783
4784
4785 int inflate_trees_dynamic(nl, nd, c, bl, bd, tl, td, hp, z)
4786 uInt nl; /* number of literal/length codes */
4787 uInt nd; /* number of distance codes */
4788 uIntf *c; /* that many (total) code lengths */
4789 uIntf *bl; /* literal desired/actual bit depth */
4790 uIntf *bd; /* distance desired/actual bit depth */
4791 inflate_huft * FAR *tl; /* literal/length tree result */
4792 inflate_huft * FAR *td; /* distance tree result */
4793 inflate_huft *hp; /* space for trees */
4794 z_streamp z; /* for messages */
4795 {
4796 int r;
4797 uInt hn = 0; /* hufts used in space */
4798 uIntf *v; /* work area for huft_build */
4799
4800 /* allocate work area */
4801 if ((v = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
4802 return Z_MEM_ERROR;
4803
4804 /* build literal/length tree */
4805 r = huft_build(c, nl, 257, cplens, cplext, tl, bl, hp, &hn, v);
4806 if (r != Z_OK || *bl == 0)
4807 {
4808 if (r == Z_DATA_ERROR)
4809 z->msg = (char*)"oversubscribed literal/length tree";
4810 else if (r != Z_MEM_ERROR)
4811 {
4812 z->msg = (char*)"incomplete literal/length tree";
4813 r = Z_DATA_ERROR;
4814 }
4815 ZFREE(z, v);
4816 return r;
4817 }
4818
4819 /* build distance tree */
4820 r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, hp, &hn, v);
4821 if (r != Z_OK || (*bd == 0 && nl > 257))
4822 {
4823 if (r == Z_DATA_ERROR)
4824 z->msg = (char*)"oversubscribed distance tree";
4825 else if (r == Z_BUF_ERROR) {
4826 #ifdef PKZIP_BUG_WORKAROUND
4827 r = Z_OK;
4828 }
4829 #else
4830 z->msg = (char*)"incomplete distance tree";
4831 r = Z_DATA_ERROR;
4832 }
4833 else if (r != Z_MEM_ERROR)
4834 {
4835 z->msg = (char*)"empty distance tree with lengths";
4836 r = Z_DATA_ERROR;
4837 }
4838 ZFREE(z, v);
4839 return r;
4840 #endif
4841 }
4842
4843 /* done */
4844 ZFREE(z, v);
4845 return Z_OK;
4846 }
4847
4848
4849 /* build fixed tables only once--keep them here */
4850 #ifdef BUILDFIXED
4851 local int fixed_built = 0;
4852 #define FIXEDH 544 /* number of hufts used by fixed tables */
4853 local inflate_huft fixed_mem[FIXEDH];
4854 local uInt fixed_bl;
4855 local uInt fixed_bd;
4856 local inflate_huft *fixed_tl;
4857 local inflate_huft *fixed_td;
4858 #else
4859
4860 /* +++ inffixed.h */
4861 /* inffixed.h -- table for decoding fixed codes
4862 * Generated automatically by the maketree.c program
4863 */
4864
4865 /* WARNING: this file should *not* be used by applications. It is
4866 part of the implementation of the compression library and is
4867 subject to change. Applications should only use zlib.h.
4868 */
4869
4870 local uInt fixed_bl = 9;
4871 local uInt fixed_bd = 5;
4872 local inflate_huft fixed_tl[] = {
4873 {{{96,7}},256}, {{{0,8}},80}, {{{0,8}},16}, {{{84,8}},115},
4874 {{{82,7}},31}, {{{0,8}},112}, {{{0,8}},48}, {{{0,9}},192},
4875 {{{80,7}},10}, {{{0,8}},96}, {{{0,8}},32}, {{{0,9}},160},
4876 {{{0,8}},0}, {{{0,8}},128}, {{{0,8}},64}, {{{0,9}},224},
4877 {{{80,7}},6}, {{{0,8}},88}, {{{0,8}},24}, {{{0,9}},144},
4878 {{{83,7}},59}, {{{0,8}},120}, {{{0,8}},56}, {{{0,9}},208},
4879 {{{81,7}},17}, {{{0,8}},104}, {{{0,8}},40}, {{{0,9}},176},
4880 {{{0,8}},8}, {{{0,8}},136}, {{{0,8}},72}, {{{0,9}},240},
4881 {{{80,7}},4}, {{{0,8}},84}, {{{0,8}},20}, {{{85,8}},227},
4882 {{{83,7}},43}, {{{0,8}},116}, {{{0,8}},52}, {{{0,9}},200},
4883 {{{81,7}},13}, {{{0,8}},100}, {{{0,8}},36}, {{{0,9}},168},
4884 {{{0,8}},4}, {{{0,8}},132}, {{{0,8}},68}, {{{0,9}},232},
4885 {{{80,7}},8}, {{{0,8}},92}, {{{0,8}},28}, {{{0,9}},152},
4886 {{{84,7}},83}, {{{0,8}},124}, {{{0,8}},60}, {{{0,9}},216},
4887 {{{82,7}},23}, {{{0,8}},108}, {{{0,8}},44}, {{{0,9}},184},
4888 {{{0,8}},12}, {{{0,8}},140}, {{{0,8}},76}, {{{0,9}},248},
4889 {{{80,7}},3}, {{{0,8}},82}, {{{0,8}},18}, {{{85,8}},163},
4890 {{{83,7}},35}, {{{0,8}},114}, {{{0,8}},50}, {{{0,9}},196},
4891 {{{81,7}},11}, {{{0,8}},98}, {{{0,8}},34}, {{{0,9}},164},
4892 {{{0,8}},2}, {{{0,8}},130}, {{{0,8}},66}, {{{0,9}},228},
4893 {{{80,7}},7}, {{{0,8}},90}, {{{0,8}},26}, {{{0,9}},148},
4894 {{{84,7}},67}, {{{0,8}},122}, {{{0,8}},58}, {{{0,9}},212},
4895 {{{82,7}},19}, {{{0,8}},106}, {{{0,8}},42}, {{{0,9}},180},
4896 {{{0,8}},10}, {{{0,8}},138}, {{{0,8}},74}, {{{0,9}},244},
4897 {{{80,7}},5}, {{{0,8}},86}, {{{0,8}},22}, {{{192,8}},0},
4898 {{{83,7}},51}, {{{0,8}},118}, {{{0,8}},54}, {{{0,9}},204},
4899 {{{81,7}},15}, {{{0,8}},102}, {{{0,8}},38}, {{{0,9}},172},
4900 {{{0,8}},6}, {{{0,8}},134}, {{{0,8}},70}, {{{0,9}},236},
4901 {{{80,7}},9}, {{{0,8}},94}, {{{0,8}},30}, {{{0,9}},156},
4902 {{{84,7}},99}, {{{0,8}},126}, {{{0,8}},62}, {{{0,9}},220},
4903 {{{82,7}},27}, {{{0,8}},110}, {{{0,8}},46}, {{{0,9}},188},
4904 {{{0,8}},14}, {{{0,8}},142}, {{{0,8}},78}, {{{0,9}},252},
4905 {{{96,7}},256}, {{{0,8}},81}, {{{0,8}},17}, {{{85,8}},131},
4906 {{{82,7}},31}, {{{0,8}},113}, {{{0,8}},49}, {{{0,9}},194},
4907 {{{80,7}},10}, {{{0,8}},97}, {{{0,8}},33}, {{{0,9}},162},
4908 {{{0,8}},1}, {{{0,8}},129}, {{{0,8}},65}, {{{0,9}},226},
4909 {{{80,7}},6}, {{{0,8}},89}, {{{0,8}},25}, {{{0,9}},146},
4910 {{{83,7}},59}, {{{0,8}},121}, {{{0,8}},57}, {{{0,9}},210},
4911 {{{81,7}},17}, {{{0,8}},105}, {{{0,8}},41}, {{{0,9}},178},
4912 {{{0,8}},9}, {{{0,8}},137}, {{{0,8}},73}, {{{0,9}},242},
4913 {{{80,7}},4}, {{{0,8}},85}, {{{0,8}},21}, {{{80,8}},258},
4914 {{{83,7}},43}, {{{0,8}},117}, {{{0,8}},53}, {{{0,9}},202},
4915 {{{81,7}},13}, {{{0,8}},101}, {{{0,8}},37}, {{{0,9}},170},
4916 {{{0,8}},5}, {{{0,8}},133}, {{{0,8}},69}, {{{0,9}},234},
4917 {{{80,7}},8}, {{{0,8}},93}, {{{0,8}},29}, {{{0,9}},154},
4918 {{{84,7}},83}, {{{0,8}},125}, {{{0,8}},61}, {{{0,9}},218},
4919 {{{82,7}},23}, {{{0,8}},109}, {{{0,8}},45}, {{{0,9}},186},
4920 {{{0,8}},13}, {{{0,8}},141}, {{{0,8}},77}, {{{0,9}},250},
4921 {{{80,7}},3}, {{{0,8}},83}, {{{0,8}},19}, {{{85,8}},195},
4922 {{{83,7}},35}, {{{0,8}},115}, {{{0,8}},51}, {{{0,9}},198},
4923 {{{81,7}},11}, {{{0,8}},99}, {{{0,8}},35}, {{{0,9}},166},
4924 {{{0,8}},3}, {{{0,8}},131}, {{{0,8}},67}, {{{0,9}},230},
4925 {{{80,7}},7}, {{{0,8}},91}, {{{0,8}},27}, {{{0,9}},150},
4926 {{{84,7}},67}, {{{0,8}},123}, {{{0,8}},59}, {{{0,9}},214},
4927 {{{82,7}},19}, {{{0,8}},107}, {{{0,8}},43}, {{{0,9}},182},
4928 {{{0,8}},11}, {{{0,8}},139}, {{{0,8}},75}, {{{0,9}},246},
4929 {{{80,7}},5}, {{{0,8}},87}, {{{0,8}},23}, {{{192,8}},0},
4930 {{{83,7}},51}, {{{0,8}},119}, {{{0,8}},55}, {{{0,9}},206},
4931 {{{81,7}},15}, {{{0,8}},103}, {{{0,8}},39}, {{{0,9}},174},
4932 {{{0,8}},7}, {{{0,8}},135}, {{{0,8}},71}, {{{0,9}},238},
4933 {{{80,7}},9}, {{{0,8}},95}, {{{0,8}},31}, {{{0,9}},158},
4934 {{{84,7}},99}, {{{0,8}},127}, {{{0,8}},63}, {{{0,9}},222},
4935 {{{82,7}},27}, {{{0,8}},111}, {{{0,8}},47}, {{{0,9}},190},
4936 {{{0,8}},15}, {{{0,8}},143}, {{{0,8}},79}, {{{0,9}},254},
4937 {{{96,7}},256}, {{{0,8}},80}, {{{0,8}},16}, {{{84,8}},115},
4938 {{{82,7}},31}, {{{0,8}},112}, {{{0,8}},48}, {{{0,9}},193},
4939 {{{80,7}},10}, {{{0,8}},96}, {{{0,8}},32}, {{{0,9}},161},
4940 {{{0,8}},0}, {{{0,8}},128}, {{{0,8}},64}, {{{0,9}},225},
4941 {{{80,7}},6}, {{{0,8}},88}, {{{0,8}},24}, {{{0,9}},145},
4942 {{{83,7}},59}, {{{0,8}},120}, {{{0,8}},56}, {{{0,9}},209},
4943 {{{81,7}},17}, {{{0,8}},104}, {{{0,8}},40}, {{{0,9}},177},
4944 {{{0,8}},8}, {{{0,8}},136}, {{{0,8}},72}, {{{0,9}},241},
4945 {{{80,7}},4}, {{{0,8}},84}, {{{0,8}},20}, {{{85,8}},227},
4946 {{{83,7}},43}, {{{0,8}},116}, {{{0,8}},52}, {{{0,9}},201},
4947 {{{81,7}},13}, {{{0,8}},100}, {{{0,8}},36}, {{{0,9}},169},
4948 {{{0,8}},4}, {{{0,8}},132}, {{{0,8}},68}, {{{0,9}},233},
4949 {{{80,7}},8}, {{{0,8}},92}, {{{0,8}},28}, {{{0,9}},153},
4950 {{{84,7}},83}, {{{0,8}},124}, {{{0,8}},60}, {{{0,9}},217},
4951 {{{82,7}},23}, {{{0,8}},108}, {{{0,8}},44}, {{{0,9}},185},
4952 {{{0,8}},12}, {{{0,8}},140}, {{{0,8}},76}, {{{0,9}},249},
4953 {{{80,7}},3}, {{{0,8}},82}, {{{0,8}},18}, {{{85,8}},163},
4954 {{{83,7}},35}, {{{0,8}},114}, {{{0,8}},50}, {{{0,9}},197},
4955 {{{81,7}},11}, {{{0,8}},98}, {{{0,8}},34}, {{{0,9}},165},
4956 {{{0,8}},2}, {{{0,8}},130}, {{{0,8}},66}, {{{0,9}},229},
4957 {{{80,7}},7}, {{{0,8}},90}, {{{0,8}},26}, {{{0,9}},149},
4958 {{{84,7}},67}, {{{0,8}},122}, {{{0,8}},58}, {{{0,9}},213},
4959 {{{82,7}},19}, {{{0,8}},106}, {{{0,8}},42}, {{{0,9}},181},
4960 {{{0,8}},10}, {{{0,8}},138}, {{{0,8}},74}, {{{0,9}},245},
4961 {{{80,7}},5}, {{{0,8}},86}, {{{0,8}},22}, {{{192,8}},0},
4962 {{{83,7}},51}, {{{0,8}},118}, {{{0,8}},54}, {{{0,9}},205},
4963 {{{81,7}},15}, {{{0,8}},102}, {{{0,8}},38}, {{{0,9}},173},
4964 {{{0,8}},6}, {{{0,8}},134}, {{{0,8}},70}, {{{0,9}},237},
4965 {{{80,7}},9}, {{{0,8}},94}, {{{0,8}},30}, {{{0,9}},157},
4966 {{{84,7}},99}, {{{0,8}},126}, {{{0,8}},62}, {{{0,9}},221},
4967 {{{82,7}},27}, {{{0,8}},110}, {{{0,8}},46}, {{{0,9}},189},
4968 {{{0,8}},14}, {{{0,8}},142}, {{{0,8}},78}, {{{0,9}},253},
4969 {{{96,7}},256}, {{{0,8}},81}, {{{0,8}},17}, {{{85,8}},131},
4970 {{{82,7}},31}, {{{0,8}},113}, {{{0,8}},49}, {{{0,9}},195},
4971 {{{80,7}},10}, {{{0,8}},97}, {{{0,8}},33}, {{{0,9}},163},
4972 {{{0,8}},1}, {{{0,8}},129}, {{{0,8}},65}, {{{0,9}},227},
4973 {{{80,7}},6}, {{{0,8}},89}, {{{0,8}},25}, {{{0,9}},147},
4974 {{{83,7}},59}, {{{0,8}},121}, {{{0,8}},57}, {{{0,9}},211},
4975 {{{81,7}},17}, {{{0,8}},105}, {{{0,8}},41}, {{{0,9}},179},
4976 {{{0,8}},9}, {{{0,8}},137}, {{{0,8}},73}, {{{0,9}},243},
4977 {{{80,7}},4}, {{{0,8}},85}, {{{0,8}},21}, {{{80,8}},258},
4978 {{{83,7}},43}, {{{0,8}},117}, {{{0,8}},53}, {{{0,9}},203},
4979 {{{81,7}},13}, {{{0,8}},101}, {{{0,8}},37}, {{{0,9}},171},
4980 {{{0,8}},5}, {{{0,8}},133}, {{{0,8}},69}, {{{0,9}},235},
4981 {{{80,7}},8}, {{{0,8}},93}, {{{0,8}},29}, {{{0,9}},155},
4982 {{{84,7}},83}, {{{0,8}},125}, {{{0,8}},61}, {{{0,9}},219},
4983 {{{82,7}},23}, {{{0,8}},109}, {{{0,8}},45}, {{{0,9}},187},
4984 {{{0,8}},13}, {{{0,8}},141}, {{{0,8}},77}, {{{0,9}},251},
4985 {{{80,7}},3}, {{{0,8}},83}, {{{0,8}},19}, {{{85,8}},195},
4986 {{{83,7}},35}, {{{0,8}},115}, {{{0,8}},51}, {{{0,9}},199},
4987 {{{81,7}},11}, {{{0,8}},99}, {{{0,8}},35}, {{{0,9}},167},
4988 {{{0,8}},3}, {{{0,8}},131}, {{{0,8}},67}, {{{0,9}},231},
4989 {{{80,7}},7}, {{{0,8}},91}, {{{0,8}},27}, {{{0,9}},151},
4990 {{{84,7}},67}, {{{0,8}},123}, {{{0,8}},59}, {{{0,9}},215},
4991 {{{82,7}},19}, {{{0,8}},107}, {{{0,8}},43}, {{{0,9}},183},
4992 {{{0,8}},11}, {{{0,8}},139}, {{{0,8}},75}, {{{0,9}},247},
4993 {{{80,7}},5}, {{{0,8}},87}, {{{0,8}},23}, {{{192,8}},0},
4994 {{{83,7}},51}, {{{0,8}},119}, {{{0,8}},55}, {{{0,9}},207},
4995 {{{81,7}},15}, {{{0,8}},103}, {{{0,8}},39}, {{{0,9}},175},
4996 {{{0,8}},7}, {{{0,8}},135}, {{{0,8}},71}, {{{0,9}},239},
4997 {{{80,7}},9}, {{{0,8}},95}, {{{0,8}},31}, {{{0,9}},159},
4998 {{{84,7}},99}, {{{0,8}},127}, {{{0,8}},63}, {{{0,9}},223},
4999 {{{82,7}},27}, {{{0,8}},111}, {{{0,8}},47}, {{{0,9}},191},
5000 {{{0,8}},15}, {{{0,8}},143}, {{{0,8}},79}, {{{0,9}},255}
5001 };
5002 local inflate_huft fixed_td[] = {
5003 {{{80,5}},1}, {{{87,5}},257}, {{{83,5}},17}, {{{91,5}},4097},
5004 {{{81,5}},5}, {{{89,5}},1025}, {{{85,5}},65}, {{{93,5}},16385},
5005 {{{80,5}},3}, {{{88,5}},513}, {{{84,5}},33}, {{{92,5}},8193},
5006 {{{82,5}},9}, {{{90,5}},2049}, {{{86,5}},129}, {{{192,5}},24577},
5007 {{{80,5}},2}, {{{87,5}},385}, {{{83,5}},25}, {{{91,5}},6145},
5008 {{{81,5}},7}, {{{89,5}},1537}, {{{85,5}},97}, {{{93,5}},24577},
5009 {{{80,5}},4}, {{{88,5}},769}, {{{84,5}},49}, {{{92,5}},12289},
5010 {{{82,5}},13}, {{{90,5}},3073}, {{{86,5}},193}, {{{192,5}},24577}
5011 };
5012 /* --- inffixed.h */
5013
5014 #endif
5015
5016
5017 int inflate_trees_fixed(bl, bd, tl, td, z)
5018 uIntf *bl; /* literal desired/actual bit depth */
5019 uIntf *bd; /* distance desired/actual bit depth */
5020 inflate_huft * FAR *tl; /* literal/length tree result */
5021 inflate_huft * FAR *td; /* distance tree result */
5022 z_streamp z; /* for memory allocation */
5023 {
5024 #ifdef BUILDFIXED
5025 /* build fixed tables if not already */
5026 if (!fixed_built)
5027 {
5028 int k; /* temporary variable */
5029 uInt f = 0; /* number of hufts used in fixed_mem */
5030 uIntf *c; /* length list for huft_build */
5031 uIntf *v; /* work area for huft_build */
5032
5033 /* allocate memory */
5034 if ((c = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
5035 return Z_MEM_ERROR;
5036 if ((v = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
5037 {
5038 ZFREE(z, c);
5039 return Z_MEM_ERROR;
5040 }
5041
5042 /* literal table */
5043 for (k = 0; k < 144; k++)
5044 c[k] = 8;
5045 for (; k < 256; k++)
5046 c[k] = 9;
5047 for (; k < 280; k++)
5048 c[k] = 7;
5049 for (; k < 288; k++)
5050 c[k] = 8;
5051 fixed_bl = 9;
5052 huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl,
5053 fixed_mem, &f, v);
5054
5055 /* distance table */
5056 for (k = 0; k < 30; k++)
5057 c[k] = 5;
5058 fixed_bd = 5;
5059 huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd,
5060 fixed_mem, &f, v);
5061
5062 /* done */
5063 ZFREE(z, v);
5064 ZFREE(z, c);
5065 fixed_built = 1;
5066 }
5067 #endif
5068 *bl = fixed_bl;
5069 *bd = fixed_bd;
5070 *tl = fixed_tl;
5071 *td = fixed_td;
5072 return Z_OK;
5073 }
5074 /* --- inftrees.c */
5075
5076 /* +++ infcodes.c */
5077
5078 /* infcodes.c -- process literals and length/distance pairs
5079 * Copyright (C) 1995-2002 Mark Adler
5080 * For conditions of distribution and use, see copyright notice in zlib.h
5081 */
5082
5083 /* #include "zutil.h" */
5084 /* #include "inftrees.h" */
5085 /* #include "infblock.h" */
5086 /* #include "infcodes.h" */
5087 /* #include "infutil.h" */
5088
5089 /* +++ inffast.h */
5090
5091 /* inffast.h -- header to use inffast.c
5092 * Copyright (C) 1995-2002 Mark Adler
5093 * For conditions of distribution and use, see copyright notice in zlib.h
5094 */
5095
5096 /* WARNING: this file should *not* be used by applications. It is
5097 part of the implementation of the compression library and is
5098 subject to change. Applications should only use zlib.h.
5099 */
5100
5101 extern int inflate_fast __P((
5102 uInt,
5103 uInt,
5104 inflate_huft *,
5105 inflate_huft *,
5106 inflate_blocks_statef *,
5107 z_streamp ));
5108 /* --- inffast.h */
5109
5110 /* simplify the use of the inflate_huft type with some defines */
5111 #define exop word.what.Exop
5112 #define bits word.what.Bits
5113
5114 typedef enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
5115 START, /* x: set up for LEN */
5116 LEN, /* i: get length/literal/eob next */
5117 LENEXT, /* i: getting length extra (have base) */
5118 DIST, /* i: get distance next */
5119 DISTEXT, /* i: getting distance extra */
5120 COPY, /* o: copying bytes in window, waiting for space */
5121 LIT, /* o: got literal, waiting for output space */
5122 WASH, /* o: got eob, possibly still output waiting */
5123 END, /* x: got eob and all data flushed */
5124 BADCODE} /* x: got error */
5125 inflate_codes_mode;
5126
5127 /* inflate codes private state */
5128 struct inflate_codes_state {
5129
5130 /* mode */
5131 inflate_codes_mode mode; /* current inflate_codes mode */
5132
5133 /* mode dependent information */
5134 uInt len;
5135 union {
5136 struct {
5137 inflate_huft *tree; /* pointer into tree */
5138 uInt need; /* bits needed */
5139 } code; /* if LEN or DIST, where in tree */
5140 uInt lit; /* if LIT, literal */
5141 struct {
5142 uInt get; /* bits to get for extra */
5143 uInt dist; /* distance back to copy from */
5144 } copy; /* if EXT or COPY, where and how much */
5145 } sub; /* submode */
5146
5147 /* mode independent information */
5148 Byte lbits; /* ltree bits decoded per branch */
5149 Byte dbits; /* dtree bits decoder per branch */
5150 inflate_huft *ltree; /* literal/length/eob tree */
5151 inflate_huft *dtree; /* distance tree */
5152
5153 };
5154
5155
5156 inflate_codes_statef *inflate_codes_new(bl, bd, tl, td, z)
5157 uInt bl, bd;
5158 inflate_huft *tl;
5159 inflate_huft *td; /* need separate declaration for Borland C++ */
5160 z_streamp z;
5161 {
5162 inflate_codes_statef *c;
5163
5164 if ((c = (inflate_codes_statef *)
5165 ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL)
5166 {
5167 c->mode = START;
5168 c->lbits = (Byte)bl;
5169 c->dbits = (Byte)bd;
5170 c->ltree = tl;
5171 c->dtree = td;
5172 Tracev((stderr, "inflate: codes new\n"));
5173 }
5174 return c;
5175 }
5176
5177
5178 int inflate_codes(s, z, r)
5179 inflate_blocks_statef *s;
5180 z_streamp z;
5181 int r;
5182 {
5183 uInt j; /* temporary storage */
5184 inflate_huft *t; /* temporary pointer */
5185 uInt e; /* extra bits or operation */
5186 uLong b; /* bit buffer */
5187 uInt k; /* bits in bit buffer */
5188 Bytef *p; /* input data pointer */
5189 uInt n; /* bytes available there */
5190 Bytef *q; /* output window write pointer */
5191 uInt m; /* bytes to end of window or read pointer */
5192 Bytef *f; /* pointer to copy strings from */
5193 inflate_codes_statef *c = s->sub.decode.codes; /* codes state */
5194
5195 /* copy input/output information to locals (UPDATE macro restores) */
5196 LOAD
5197
5198 /* process input and output based on current state */
5199 while (1) switch (c->mode)
5200 { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
5201 case START: /* x: set up for LEN */
5202 #ifndef SLOW
5203 if (m >= 258 && n >= 10)
5204 {
5205 UPDATE
5206 r = inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z);
5207 LOAD
5208 if (r != Z_OK)
5209 {
5210 c->mode = r == Z_STREAM_END ? WASH : BADCODE;
5211 break;
5212 }
5213 }
5214 #endif /* !SLOW */
5215 c->sub.code.need = c->lbits;
5216 c->sub.code.tree = c->ltree;
5217 c->mode = LEN;
5218 case LEN: /* i: get length/literal/eob next */
5219 j = c->sub.code.need;
5220 NEEDBITS(j)
5221 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
5222 DUMPBITS(t->bits)
5223 e = (uInt)(t->exop);
5224 if (e == 0) /* literal */
5225 {
5226 c->sub.lit = t->base;
5227 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5228 "inflate: literal '%c'\n" :
5229 "inflate: literal 0x%02x\n", t->base));
5230 c->mode = LIT;
5231 break;
5232 }
5233 if (e & 16) /* length */
5234 {
5235 c->sub.copy.get = e & 15;
5236 c->len = t->base;
5237 c->mode = LENEXT;
5238 break;
5239 }
5240 if ((e & 64) == 0) /* next table */
5241 {
5242 c->sub.code.need = e;
5243 c->sub.code.tree = t + t->base;
5244 break;
5245 }
5246 if (e & 32) /* end of block */
5247 {
5248 Tracevv((stderr, "inflate: end of block\n"));
5249 c->mode = WASH;
5250 break;
5251 }
5252 c->mode = BADCODE; /* invalid code */
5253 z->msg = (char*)"invalid literal/length code";
5254 r = Z_DATA_ERROR;
5255 LEAVE
5256 case LENEXT: /* i: getting length extra (have base) */
5257 j = c->sub.copy.get;
5258 NEEDBITS(j)
5259 c->len += (uInt)b & inflate_mask[j];
5260 DUMPBITS(j)
5261 c->sub.code.need = c->dbits;
5262 c->sub.code.tree = c->dtree;
5263 Tracevv((stderr, "inflate: length %u\n", c->len));
5264 c->mode = DIST;
5265 case DIST: /* i: get distance next */
5266 j = c->sub.code.need;
5267 NEEDBITS(j)
5268 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
5269 DUMPBITS(t->bits)
5270 e = (uInt)(t->exop);
5271 if (e & 16) /* distance */
5272 {
5273 c->sub.copy.get = e & 15;
5274 c->sub.copy.dist = t->base;
5275 c->mode = DISTEXT;
5276 break;
5277 }
5278 if ((e & 64) == 0) /* next table */
5279 {
5280 c->sub.code.need = e;
5281 c->sub.code.tree = t + t->base;
5282 break;
5283 }
5284 c->mode = BADCODE; /* invalid code */
5285 z->msg = (char*)"invalid distance code";
5286 r = Z_DATA_ERROR;
5287 LEAVE
5288 case DISTEXT: /* i: getting distance extra */
5289 j = c->sub.copy.get;
5290 NEEDBITS(j)
5291 c->sub.copy.dist += (uInt)b & inflate_mask[j];
5292 DUMPBITS(j)
5293 Tracevv((stderr, "inflate: distance %u\n", c->sub.copy.dist));
5294 c->mode = COPY;
5295 case COPY: /* o: copying bytes in window, waiting for space */
5296 f = q - c->sub.copy.dist;
5297 while (f < s->window) /* modulo window size-"while" instead */
5298 f += s->end - s->window; /* of "if" handles invalid distances */
5299 while (c->len)
5300 {
5301 NEEDOUT
5302 OUTBYTE(*f++)
5303 if (f == s->end)
5304 f = s->window;
5305 c->len--;
5306 }
5307 c->mode = START;
5308 break;
5309 case LIT: /* o: got literal, waiting for output space */
5310 NEEDOUT
5311 OUTBYTE(c->sub.lit)
5312 c->mode = START;
5313 break;
5314 case WASH: /* o: got eob, possibly more output */
5315 if (k > 7) /* return unused byte, if any */
5316 {
5317 Assert(k < 16, "inflate_codes grabbed too many bytes")
5318 k -= 8;
5319 n++;
5320 p--; /* can always return one */
5321 }
5322 FLUSH
5323 if (s->read != s->write)
5324 LEAVE
5325 c->mode = END;
5326 case END:
5327 r = Z_STREAM_END;
5328 LEAVE
5329 case BADCODE: /* x: got error */
5330 r = Z_DATA_ERROR;
5331 LEAVE
5332 default:
5333 r = Z_STREAM_ERROR;
5334 LEAVE
5335 }
5336 #ifdef NEED_DUMMY_RETURN
5337 return Z_STREAM_ERROR; /* Some dumb compilers complain without this */
5338 #endif
5339 }
5340
5341
5342 void inflate_codes_free(c, z)
5343 inflate_codes_statef *c;
5344 z_streamp z;
5345 {
5346 ZFREE(z, c);
5347 Tracev((stderr, "inflate: codes free\n"));
5348 }
5349 /* --- infcodes.c */
5350
5351 /* +++ infutil.c */
5352
5353 /* inflate_util.c -- data and routines common to blocks and codes
5354 * Copyright (C) 1995-2002 Mark Adler
5355 * For conditions of distribution and use, see copyright notice in zlib.h
5356 */
5357
5358 /* #include "zutil.h" */
5359 /* #include "infblock.h" */
5360 /* #include "inftrees.h" */
5361 /* #include "infcodes.h" */
5362 /* #include "infutil.h" */
5363
5364 #ifndef NO_DUMMY_DECL
5365 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
5366 #endif
5367
5368 /* And'ing with mask[n] masks the lower n bits */
5369 uInt inflate_mask[17] = {
5370 0x0000,
5371 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
5372 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
5373 };
5374
5375
5376 /* copy as much as possible from the sliding window to the output area */
5377 int inflate_flush(s, z, r)
5378 inflate_blocks_statef *s;
5379 z_streamp z;
5380 int r;
5381 {
5382 uInt n;
5383 Bytef *p;
5384 Bytef *q;
5385
5386 /* local copies of source and destination pointers */
5387 p = z->next_out;
5388 q = s->read;
5389
5390 /* compute number of bytes to copy as far as end of window */
5391 n = (uInt)((q <= s->write ? s->write : s->end) - q);
5392 if (n > z->avail_out) n = z->avail_out;
5393 if (n && r == Z_BUF_ERROR) r = Z_OK;
5394
5395 /* update counters */
5396 z->avail_out -= n;
5397 z->total_out += n;
5398
5399 /* update check information */
5400 if (s->checkfn != Z_NULL)
5401 z->adler = s->check = (*s->checkfn)(s->check, q, n);
5402
5403 /* copy as far as end of window */
5404 if (p != Z_NULL) {
5405 zmemcpy(p, q, n);
5406 p += n;
5407 }
5408 q += n;
5409
5410 /* see if more to copy at beginning of window */
5411 if (q == s->end)
5412 {
5413 /* wrap pointers */
5414 q = s->window;
5415 if (s->write == s->end)
5416 s->write = s->window;
5417
5418 /* compute bytes to copy */
5419 n = (uInt)(s->write - q);
5420 if (n > z->avail_out) n = z->avail_out;
5421 if (n && r == Z_BUF_ERROR) r = Z_OK;
5422
5423 /* update counters */
5424 z->avail_out -= n;
5425 z->total_out += n;
5426
5427 /* update check information */
5428 if (s->checkfn != Z_NULL)
5429 z->adler = s->check = (*s->checkfn)(s->check, q, n);
5430
5431 /* copy */
5432 if (p != NULL) {
5433 zmemcpy(p, q, n);
5434 p += n;
5435 }
5436 q += n;
5437 }
5438
5439 /* update pointers */
5440 z->next_out = p;
5441 s->read = q;
5442
5443 /* done */
5444 return r;
5445 }
5446 /* --- infutil.c */
5447
5448 /* +++ inffast.c */
5449
5450 /* inffast.c -- process literals and length/distance pairs fast
5451 * Copyright (C) 1995-2002 Mark Adler
5452 * For conditions of distribution and use, see copyright notice in zlib.h
5453 */
5454
5455 /* #include "zutil.h" */
5456 /* #include "inftrees.h" */
5457 /* #include "infblock.h" */
5458 /* #include "infcodes.h" */
5459 /* #include "infutil.h" */
5460 /* #include "inffast.h" */
5461
5462 #ifndef NO_DUMMY_DECL
5463 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
5464 #endif
5465
5466 /* simplify the use of the inflate_huft type with some defines */
5467 #define exop word.what.Exop
5468 #define bits word.what.Bits
5469
5470 /* macros for bit input with no checking and for returning unused bytes */
5471 #define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}}
5472 #define UNGRAB {c=z->avail_in-n;c=(k>>3)<c?k>>3:c;n+=c;p-=c;k-=c<<3;}
5473
5474 /* Called with number of bytes left to write in window at least 258
5475 (the maximum string length) and number of input bytes available
5476 at least ten. The ten bytes are six bytes for the longest length/
5477 distance pair plus four bytes for overloading the bit buffer. */
5478
5479 int inflate_fast(bl, bd, tl, td, s, z)
5480 uInt bl, bd;
5481 inflate_huft *tl;
5482 inflate_huft *td; /* need separate declaration for Borland C++ */
5483 inflate_blocks_statef *s;
5484 z_streamp z;
5485 {
5486 inflate_huft *t; /* temporary pointer */
5487 uInt e; /* extra bits or operation */
5488 uLong b; /* bit buffer */
5489 uInt k; /* bits in bit buffer */
5490 Bytef *p; /* input data pointer */
5491 uInt n; /* bytes available there */
5492 Bytef *q; /* output window write pointer */
5493 uInt m; /* bytes to end of window or read pointer */
5494 uInt ml; /* mask for literal/length tree */
5495 uInt md; /* mask for distance tree */
5496 uInt c; /* bytes to copy */
5497 uInt d; /* distance back to copy from */
5498 Bytef *r; /* copy source pointer */
5499
5500 /* load input, output, bit values */
5501 LOAD
5502
5503 /* initialize masks */
5504 ml = inflate_mask[bl];
5505 md = inflate_mask[bd];
5506
5507 /* do until not enough input or output space for fast loop */
5508 do { /* assume called with m >= 258 && n >= 10 */
5509 /* get literal/length code */
5510 GRABBITS(20) /* max bits for literal/length code */
5511 if ((e = (t = tl + ((uInt)b & ml))->exop) == 0)
5512 {
5513 DUMPBITS(t->bits)
5514 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5515 "inflate: * literal '%c'\n" :
5516 "inflate: * literal 0x%02x\n", t->base));
5517 *q++ = (Byte)t->base;
5518 m--;
5519 continue;
5520 }
5521 do {
5522 DUMPBITS(t->bits)
5523 if (e & 16)
5524 {
5525 /* get extra bits for length */
5526 e &= 15;
5527 c = t->base + ((uInt)b & inflate_mask[e]);
5528 DUMPBITS(e)
5529 Tracevv((stderr, "inflate: * length %u\n", c));
5530
5531 /* decode distance base of block to copy */
5532 GRABBITS(15); /* max bits for distance code */
5533 e = (t = td + ((uInt)b & md))->exop;
5534 do {
5535 DUMPBITS(t->bits)
5536 if (e & 16)
5537 {
5538 /* get extra bits to add to distance base */
5539 e &= 15;
5540 GRABBITS(e) /* get extra bits (up to 13) */
5541 d = t->base + ((uInt)b & inflate_mask[e]);
5542 DUMPBITS(e)
5543 Tracevv((stderr, "inflate: * distance %u\n", d));
5544
5545 /* do the copy */
5546 m -= c;
5547 r = q - d;
5548 if (r < s->window) /* wrap if needed */
5549 {
5550 do {
5551 r += s->end - s->window; /* force pointer in window */
5552 } while (r < s->window); /* covers invalid distances */
5553 e = s->end - r;
5554 if (c > e)
5555 {
5556 c -= e; /* wrapped copy */
5557 do {
5558 *q++ = *r++;
5559 } while (--e);
5560 r = s->window;
5561 do {
5562 *q++ = *r++;
5563 } while (--c);
5564 }
5565 else /* normal copy */
5566 {
5567 *q++ = *r++; c--;
5568 *q++ = *r++; c--;
5569 do {
5570 *q++ = *r++;
5571 } while (--c);
5572 }
5573 }
5574 else /* normal copy */
5575 {
5576 *q++ = *r++; c--;
5577 *q++ = *r++; c--;
5578 do {
5579 *q++ = *r++;
5580 } while (--c);
5581 }
5582 break;
5583 }
5584 else if ((e & 64) == 0)
5585 {
5586 t += t->base;
5587 e = (t += ((uInt)b & inflate_mask[e]))->exop;
5588 }
5589 else
5590 {
5591 z->msg = (char*)"invalid distance code";
5592 UNGRAB
5593 UPDATE
5594 return Z_DATA_ERROR;
5595 }
5596 } while (1);
5597 break;
5598 }
5599 if ((e & 64) == 0)
5600 {
5601 t += t->base;
5602 if ((e = (t += ((uInt)b & inflate_mask[e]))->exop) == 0)
5603 {
5604 DUMPBITS(t->bits)
5605 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5606 "inflate: * literal '%c'\n" :
5607 "inflate: * literal 0x%02x\n", t->base));
5608 *q++ = (Byte)t->base;
5609 m--;
5610 break;
5611 }
5612 }
5613 else if (e & 32)
5614 {
5615 Tracevv((stderr, "inflate: * end of block\n"));
5616 UNGRAB
5617 UPDATE
5618 return Z_STREAM_END;
5619 }
5620 else
5621 {
5622 z->msg = (char*)"invalid literal/length code";
5623 UNGRAB
5624 UPDATE
5625 return Z_DATA_ERROR;
5626 }
5627 } while (1);
5628 } while (m >= 258 && n >= 10);
5629
5630 /* not enough input or output--restore pointers and return */
5631 UNGRAB
5632 UPDATE
5633 return Z_OK;
5634 }
5635 /* --- inffast.c */
5636
5637 /* +++ zutil.c */
5638
5639 /* zutil.c -- target dependent utility functions for the compression library
5640 * Copyright (C) 1995-2002 Jean-loup Gailly.
5641 * For conditions of distribution and use, see copyright notice in zlib.h
5642 */
5643
5644 /* @(#) Id */
5645
5646 #ifdef DEBUG_ZLIB
5647 #include <stdio.h>
5648 #endif
5649
5650 /* #include "zutil.h" */
5651
5652 #ifndef NO_DUMMY_DECL
5653 struct internal_state {int dummy;}; /* for buggy compilers */
5654 #endif
5655
5656 #ifndef STDC
5657 extern void exit __P((int));
5658 #endif
5659
5660 const char *z_errmsg[10] = {
5661 "need dictionary", /* Z_NEED_DICT 2 */
5662 "stream end", /* Z_STREAM_END 1 */
5663 "", /* Z_OK 0 */
5664 "file error", /* Z_ERRNO (-1) */
5665 "stream error", /* Z_STREAM_ERROR (-2) */
5666 "data error", /* Z_DATA_ERROR (-3) */
5667 "insufficient memory", /* Z_MEM_ERROR (-4) */
5668 "buffer error", /* Z_BUF_ERROR (-5) */
5669 "incompatible version",/* Z_VERSION_ERROR (-6) */
5670 ""};
5671
5672
5673 const char * ZEXPORT zlibVersion()
5674 {
5675 return ZLIB_VERSION;
5676 }
5677
5678 #ifdef DEBUG_ZLIB
5679
5680 # ifndef verbose
5681 # define verbose 0
5682 # endif
5683 int z_verbose = verbose;
5684
5685 void z_error (m)
5686 char *m;
5687 {
5688 fprintf(stderr, "%s\n", m);
5689 exit(1);
5690 }
5691 #endif
5692
5693 /* exported to allow conversion of error code to string for compress() and
5694 * uncompress()
5695 */
5696 const char * ZEXPORT zError(err)
5697 int err;
5698 {
5699 return ERR_MSG(err);
5700 }
5701
5702
5703 #ifndef HAVE_MEMCPY
5704
5705 void zmemcpy(dest, source, len)
5706 Bytef* dest;
5707 const Bytef* source;
5708 uInt len;
5709 {
5710 if (len == 0) return;
5711 do {
5712 *dest++ = *source++; /* ??? to be unrolled */
5713 } while (--len != 0);
5714 }
5715
5716 int zmemcmp(s1, s2, len)
5717 const Bytef* s1;
5718 const Bytef* s2;
5719 uInt len;
5720 {
5721 uInt j;
5722
5723 for (j = 0; j < len; j++) {
5724 if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1;
5725 }
5726 return 0;
5727 }
5728
5729 void zmemzero(dest, len)
5730 Bytef* dest;
5731 uInt len;
5732 {
5733 if (len == 0) return;
5734 do {
5735 *dest++ = 0; /* ??? to be unrolled */
5736 } while (--len != 0);
5737 }
5738 #endif
5739
5740 #ifdef __TURBOC__
5741 #if (defined( __BORLANDC__) || !defined(SMALL_MEDIUM)) && !defined(__32BIT__)
5742 /* Small and medium model in Turbo C are for now limited to near allocation
5743 * with reduced MAX_WBITS and MAX_MEM_LEVEL
5744 */
5745 # define MY_ZCALLOC
5746
5747 /* Turbo C malloc() does not allow dynamic allocation of 64K bytes
5748 * and farmalloc(64K) returns a pointer with an offset of 8, so we
5749 * must fix the pointer. Warning: the pointer must be put back to its
5750 * original form in order to free it, use zcfree().
5751 */
5752
5753 #define MAX_PTR 10
5754 /* 10*64K = 640K */
5755
5756 local int next_ptr = 0;
5757
5758 typedef struct ptr_table_s {
5759 voidpf org_ptr;
5760 voidpf new_ptr;
5761 } ptr_table;
5762
5763 local ptr_table table[MAX_PTR];
5764 /* This table is used to remember the original form of pointers
5765 * to large buffers (64K). Such pointers are normalized with a zero offset.
5766 * Since MSDOS is not a preemptive multitasking OS, this table is not
5767 * protected from concurrent access. This hack doesn't work anyway on
5768 * a protected system like OS/2. Use Microsoft C instead.
5769 */
5770
5771 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
5772 {
5773 voidpf buf = opaque; /* just to make some compilers happy */
5774 ulg bsize = (ulg)items*size;
5775
5776 /* If we allocate less than 65520 bytes, we assume that farmalloc
5777 * will return a usable pointer which doesn't have to be normalized.
5778 */
5779 if (bsize < 65520L) {
5780 buf = farmalloc(bsize);
5781 if (*(ush*)&buf != 0) return buf;
5782 } else {
5783 buf = farmalloc(bsize + 16L);
5784 }
5785 if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
5786 table[next_ptr].org_ptr = buf;
5787
5788 /* Normalize the pointer to seg:0 */
5789 *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
5790 *(ush*)&buf = 0;
5791 table[next_ptr++].new_ptr = buf;
5792 return buf;
5793 }
5794
5795 void zcfree (voidpf opaque, voidpf ptr)
5796 {
5797 int n;
5798 if (*(ush*)&ptr != 0) { /* object < 64K */
5799 farfree(ptr);
5800 return;
5801 }
5802 /* Find the original pointer */
5803 for (n = 0; n < next_ptr; n++) {
5804 if (ptr != table[n].new_ptr) continue;
5805
5806 farfree(table[n].org_ptr);
5807 while (++n < next_ptr) {
5808 table[n-1] = table[n];
5809 }
5810 next_ptr--;
5811 return;
5812 }
5813 ptr = opaque; /* just to make some compilers happy */
5814 Assert(0, "zcfree: ptr not found");
5815 }
5816 #endif
5817 #endif /* __TURBOC__ */
5818
5819
5820 #if defined(M_I86) && !defined(__32BIT__)
5821 /* Microsoft C in 16-bit mode */
5822
5823 # define MY_ZCALLOC
5824
5825 #if (!defined(_MSC_VER) || (_MSC_VER <= 600))
5826 # define _halloc halloc
5827 # define _hfree hfree
5828 #endif
5829
5830 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
5831 {
5832 if (opaque) opaque = 0; /* to make compiler happy */
5833 return _halloc((long)items, size);
5834 }
5835
5836 void zcfree (voidpf opaque, voidpf ptr)
5837 {
5838 if (opaque) opaque = 0; /* to make compiler happy */
5839 _hfree(ptr);
5840 }
5841
5842 #endif /* MSC */
5843
5844
5845 #ifndef MY_ZCALLOC /* Any system without a special alloc function */
5846
5847 #ifndef STDC
5848 extern voidp calloc __P((uInt items, uInt size));
5849 extern void free __P((voidpf ptr));
5850 #endif
5851
5852 voidpf zcalloc (opaque, items, size)
5853 voidpf opaque;
5854 unsigned items;
5855 unsigned size;
5856 {
5857 if (opaque) items += size - size; /* make compiler happy */
5858 return (voidpf)calloc(items, size);
5859 }
5860
5861 void zcfree (opaque, ptr)
5862 voidpf opaque;
5863 voidpf ptr;
5864 {
5865 free(ptr);
5866 if (opaque) return; /* make compiler happy */
5867 }
5868
5869 #endif /* MY_ZCALLOC */
5870 /* --- zutil.c */
5871
5872 /* +++ adler32.c */
5873 /* adler32.c -- compute the Adler-32 checksum of a data stream
5874 * Copyright (C) 1995-2002 Mark Adler
5875 * For conditions of distribution and use, see copyright notice in zlib.h
5876 */
5877
5878 /* @(#) $Id: zlib.c,v 1.13.4.2 2002/03/16 16:02:09 jdolecek Exp $ */
5879
5880 /* #include "zlib.h" */
5881
5882 #define BASE 65521L /* largest prime smaller than 65536 */
5883 #define NMAX 5552
5884 /* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
5885
5886 #define DO1(buf,i) {s1 += buf[i]; s2 += s1;}
5887 #define DO2(buf,i) DO1(buf,i); DO1(buf,i+1);
5888 #define DO4(buf,i) DO2(buf,i); DO2(buf,i+2);
5889 #define DO8(buf,i) DO4(buf,i); DO4(buf,i+4);
5890 #define DO16(buf) DO8(buf,0); DO8(buf,8);
5891
5892 /* ========================================================================= */
5893 uLong ZEXPORT adler32(adler, buf, len)
5894 uLong adler;
5895 const Bytef *buf;
5896 uInt len;
5897 {
5898 unsigned long s1 = adler & 0xffff;
5899 unsigned long s2 = (adler >> 16) & 0xffff;
5900 int k;
5901
5902 if (buf == Z_NULL) return 1L;
5903
5904 while (len > 0) {
5905 k = len < NMAX ? len : NMAX;
5906 len -= k;
5907 while (k >= 16) {
5908 DO16(buf);
5909 buf += 16;
5910 k -= 16;
5911 }
5912 if (k != 0) do {
5913 s1 += *buf++;
5914 s2 += s1;
5915 } while (--k);
5916 s1 %= BASE;
5917 s2 %= BASE;
5918 }
5919 return (s2 << 16) | s1;
5920 }
5921 /* --- adler32.c */
5922
5923