FreeBSD/Linux Kernel Cross Reference
sys/net/zlib.c
1 /* $NetBSD: zlib.c,v 1.19 2002/08/20 03:52:26 kristerw 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 1.19 2002/08/20 03:52:26 kristerw 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 1.19 2002/08/20 03:52:26 kristerw 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 1.19 2002/08/20 03:52:26 kristerw 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 1.19 2002/08/20 03:52:26 kristerw 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 1.19 2002/08/20 03:52:26 kristerw 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 #if 0
801 int ZEXPORT deflateInit_(strm, level, version, stream_size)
802 z_streamp strm;
803 int level;
804 const char *version;
805 int stream_size;
806 {
807 return deflateInit2_(strm, level, Z_DEFLATED, MAX_WBITS, DEF_MEM_LEVEL,
808 Z_DEFAULT_STRATEGY, version, stream_size);
809 /* To do: ignore strm->next_in if we use it as window */
810 }
811 #endif
812
813 /* ========================================================================= */
814 int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
815 version, stream_size)
816 z_streamp strm;
817 int level;
818 int method;
819 int windowBits;
820 int memLevel;
821 int strategy;
822 const char *version;
823 int stream_size;
824 {
825 deflate_state *s;
826 int noheader = 0;
827 static const char* my_version = ZLIB_VERSION;
828
829 ushf *overlay;
830 /* We overlay pending_buf and d_buf+l_buf. This works since the average
831 * output size for (length,distance) codes is <= 24 bits.
832 */
833
834 if (version == Z_NULL || version[0] != my_version[0] ||
835 stream_size != sizeof(z_stream)) {
836 return Z_VERSION_ERROR;
837 }
838 if (strm == Z_NULL) return Z_STREAM_ERROR;
839
840 strm->msg = Z_NULL;
841 #ifndef NO_ZCFUNCS
842 if (strm->zalloc == Z_NULL) {
843 strm->zalloc = zcalloc;
844 strm->opaque = (voidpf)0;
845 }
846 if (strm->zfree == Z_NULL) strm->zfree = zcfree;
847 #endif
848
849 if (level == Z_DEFAULT_COMPRESSION) level = 6;
850 #ifdef FASTEST
851 level = 1;
852 #endif
853
854 if (windowBits < 0) { /* undocumented feature: suppress zlib header */
855 noheader = 1;
856 windowBits = -windowBits;
857 }
858 if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED ||
859 windowBits < 9 || windowBits > 15 || level < 0 || level > 9 ||
860 strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
861 return Z_STREAM_ERROR;
862 }
863 s = (deflate_state *) ZALLOC(strm, 1, sizeof(deflate_state));
864 if (s == Z_NULL) return Z_MEM_ERROR;
865 strm->state = (struct internal_state FAR *)s;
866 s->strm = strm;
867
868 s->noheader = noheader;
869 s->w_bits = windowBits;
870 s->w_size = 1 << s->w_bits;
871 s->w_mask = s->w_size - 1;
872
873 s->hash_bits = memLevel + 7;
874 s->hash_size = 1 << s->hash_bits;
875 s->hash_mask = s->hash_size - 1;
876 s->hash_shift = ((s->hash_bits+MIN_MATCH-1)/MIN_MATCH);
877
878 s->window = (Bytef *) ZALLOC(strm, s->w_size, 2*sizeof(Byte));
879 s->prev = (Posf *) ZALLOC(strm, s->w_size, sizeof(Pos));
880 s->head = (Posf *) ZALLOC(strm, s->hash_size, sizeof(Pos));
881
882 s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */
883
884 overlay = (ushf *) ZALLOC(strm, s->lit_bufsize, sizeof(ush)+2);
885 s->pending_buf = (uchf *) overlay;
886 s->pending_buf_size = (ulg)s->lit_bufsize * (sizeof(ush)+2L);
887
888 if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL ||
889 s->pending_buf == Z_NULL) {
890 strm->msg = (char*)ERR_MSG(Z_MEM_ERROR);
891 s->status = INIT_STATE;
892 deflateEnd (strm);
893 return Z_MEM_ERROR;
894 }
895 s->d_buf = overlay + s->lit_bufsize/sizeof(ush);
896 s->l_buf = s->pending_buf + (1+sizeof(ush))*s->lit_bufsize;
897
898 s->level = level;
899 s->strategy = strategy;
900 s->method = (Byte)method;
901
902 return deflateReset(strm);
903 }
904
905 /* ========================================================================= */
906 #if 0
907 int ZEXPORT deflateSetDictionary (strm, dictionary, dictLength)
908 z_streamp strm;
909 const Bytef *dictionary;
910 uInt dictLength;
911 {
912 deflate_state *s;
913 uInt length = dictLength;
914 uInt n;
915 IPos hash_head = 0;
916
917 if (strm == Z_NULL || strm->state == Z_NULL || dictionary == Z_NULL)
918 return Z_STREAM_ERROR;
919
920 s = (deflate_state *)strm->state;
921 if (s->status != INIT_STATE) return Z_STREAM_ERROR;
922
923 strm->adler = adler32(strm->adler, dictionary, dictLength);
924
925 if (length < MIN_MATCH) return Z_OK;
926 if (length > MAX_DIST(s)) {
927 length = MAX_DIST(s);
928 #ifndef USE_DICT_HEAD
929 dictionary += dictLength - length; /* use the tail of the dictionary */
930 #endif
931 }
932 zmemcpy(s->window, dictionary, length);
933 s->strstart = length;
934 s->block_start = (long)length;
935
936 /* Insert all strings in the hash table (except for the last two bytes).
937 * s->lookahead stays null, so s->ins_h will be recomputed at the next
938 * call of fill_window.
939 */
940 s->ins_h = s->window[0];
941 UPDATE_HASH(s, s->ins_h, s->window[1]);
942 for (n = 0; n <= length - MIN_MATCH; n++) {
943 INSERT_STRING(s, n, hash_head);
944 }
945 if (hash_head) hash_head = 0; /* to make compiler happy */
946 return Z_OK;
947 }
948 #endif
949
950 /* ========================================================================= */
951 int ZEXPORT deflateReset (strm)
952 z_streamp strm;
953 {
954 deflate_state *s;
955
956 if (strm == Z_NULL || strm->state == Z_NULL ||
957 strm->zalloc == Z_NULL || strm->zfree == Z_NULL) return Z_STREAM_ERROR;
958
959 strm->total_in = strm->total_out = 0;
960 strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */
961 strm->data_type = Z_UNKNOWN;
962
963 s = (deflate_state *)strm->state;
964 s->pending = 0;
965 s->pending_out = s->pending_buf;
966
967 if (s->noheader < 0) {
968 s->noheader = 0; /* was set to -1 by deflate(..., Z_FINISH); */
969 }
970 s->status = s->noheader ? BUSY_STATE : INIT_STATE;
971 strm->adler = 1;
972 s->last_flush = Z_NO_FLUSH;
973
974 _tr_init(s);
975 lm_init(s);
976
977 return Z_OK;
978 }
979
980 /* ========================================================================= */
981 #if 0
982 int ZEXPORT deflateParams(strm, level, strategy)
983 z_streamp strm;
984 int level;
985 int strategy;
986 {
987 deflate_state *s;
988 compress_func func;
989 int err = Z_OK;
990
991 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
992 s = (deflate_state *)strm->state;
993
994 if (level == Z_DEFAULT_COMPRESSION) {
995 level = 6;
996 }
997 if (level < 0 || level > 9 || strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
998 return Z_STREAM_ERROR;
999 }
1000 func = configuration_table[s->level].func;
1001
1002 if (func != configuration_table[level].func && strm->total_in != 0) {
1003 /* Flush the last buffer: */
1004 err = deflate(strm, Z_PARTIAL_FLUSH);
1005 }
1006 if (s->level != level) {
1007 s->level = level;
1008 s->max_lazy_match = configuration_table[level].max_lazy;
1009 s->good_match = configuration_table[level].good_length;
1010 s->nice_match = configuration_table[level].nice_length;
1011 s->max_chain_length = configuration_table[level].max_chain;
1012 }
1013 s->strategy = strategy;
1014 return err;
1015 }
1016 #endif
1017
1018 /* =========================================================================
1019 * Put a short in the pending buffer. The 16-bit value is put in MSB order.
1020 * IN assertion: the stream state is correct and there is enough room in
1021 * pending_buf.
1022 */
1023 local void putShortMSB (s, b)
1024 deflate_state *s;
1025 uInt b;
1026 {
1027 put_byte(s, (Byte)(b >> 8));
1028 put_byte(s, (Byte)(b & 0xff));
1029 }
1030
1031 /* =========================================================================
1032 * Flush as much pending output as possible. All deflate() output goes
1033 * through this function so some applications may wish to modify it
1034 * to avoid allocating a large strm->next_out buffer and copying into it.
1035 * (See also read_buf()).
1036 */
1037 local void flush_pending(strm)
1038 z_streamp strm;
1039 {
1040 deflate_state *s = (deflate_state *) strm->state;
1041 unsigned len = s->pending;
1042
1043 if (len > strm->avail_out) len = strm->avail_out;
1044 if (len == 0) return;
1045
1046 if (strm->next_out != Z_NULL) {
1047 zmemcpy(strm->next_out, s->pending_out, len);
1048 strm->next_out += len;
1049 }
1050 s->pending_out += len;
1051 strm->total_out += len;
1052 strm->avail_out -= len;
1053 s->pending -= len;
1054 if (s->pending == 0) {
1055 s->pending_out = s->pending_buf;
1056 }
1057 }
1058
1059 /* ========================================================================= */
1060 int ZEXPORT deflate (strm, flush)
1061 z_streamp strm;
1062 int flush;
1063 {
1064 int old_flush; /* value of flush param for previous deflate call */
1065 deflate_state *s;
1066
1067 if (strm == Z_NULL || strm->state == Z_NULL ||
1068 flush > Z_FINISH || flush < 0) {
1069 return Z_STREAM_ERROR;
1070 }
1071 s = (deflate_state *)strm->state;
1072
1073 if ((strm->next_in == Z_NULL && strm->avail_in != 0) ||
1074 (s->status == FINISH_STATE && flush != Z_FINISH)) {
1075 ERR_RETURN(strm, Z_STREAM_ERROR);
1076 }
1077 if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR);
1078
1079 s->strm = strm; /* just in case */
1080 old_flush = s->last_flush;
1081 s->last_flush = flush;
1082
1083 /* Write the zlib header */
1084 if (s->status == INIT_STATE) {
1085
1086 uInt header = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8;
1087 uInt level_flags = (s->level-1) >> 1;
1088
1089 if (level_flags > 3) level_flags = 3;
1090 header |= (level_flags << 6);
1091 if (s->strstart != 0) header |= PRESET_DICT;
1092 header += 31 - (header % 31);
1093
1094 s->status = BUSY_STATE;
1095 putShortMSB(s, header);
1096
1097 /* Save the adler32 of the preset dictionary: */
1098 if (s->strstart != 0) {
1099 putShortMSB(s, (uInt)(strm->adler >> 16));
1100 putShortMSB(s, (uInt)(strm->adler & 0xffff));
1101 }
1102 strm->adler = 1L;
1103 }
1104
1105 /* Flush as much pending output as possible */
1106 if (s->pending != 0) {
1107 flush_pending(strm);
1108 if (strm->avail_out == 0) {
1109 /* Since avail_out is 0, deflate will be called again with
1110 * more output space, but possibly with both pending and
1111 * avail_in equal to zero. There won't be anything to do,
1112 * but this is not an error situation so make sure we
1113 * return OK instead of BUF_ERROR at next call of deflate:
1114 */
1115 s->last_flush = -1;
1116 return Z_OK;
1117 }
1118
1119 /* Make sure there is something to do and avoid duplicate consecutive
1120 * flushes. For repeated and useless calls with Z_FINISH, we keep
1121 * returning Z_STREAM_END instead of Z_BUFF_ERROR.
1122 */
1123 } else if (strm->avail_in == 0 && flush <= old_flush &&
1124 flush != Z_FINISH) {
1125 ERR_RETURN(strm, Z_BUF_ERROR);
1126 }
1127
1128 /* User must not provide more input after the first FINISH: */
1129 if (s->status == FINISH_STATE && strm->avail_in != 0) {
1130 ERR_RETURN(strm, Z_BUF_ERROR);
1131 }
1132
1133 /* Start a new block or continue the current one.
1134 */
1135 if (strm->avail_in != 0 || s->lookahead != 0 ||
1136 (flush != Z_NO_FLUSH && s->status != FINISH_STATE)) {
1137 block_state bstate;
1138
1139 bstate = (*(configuration_table[s->level].func))(s, flush);
1140
1141 if (bstate == finish_started || bstate == finish_done) {
1142 s->status = FINISH_STATE;
1143 }
1144 if (bstate == need_more || bstate == finish_started) {
1145 if (strm->avail_out == 0) {
1146 s->last_flush = -1; /* avoid BUF_ERROR next call, see above */
1147 }
1148 return Z_OK;
1149 /* If flush != Z_NO_FLUSH && avail_out == 0, the next call
1150 * of deflate should use the same flush parameter to make sure
1151 * that the flush is complete. So we don't have to output an
1152 * empty block here, this will be done at next call. This also
1153 * ensures that for a very small output buffer, we emit at most
1154 * one empty block.
1155 */
1156 }
1157 if (bstate == block_done) {
1158 if (flush == Z_PARTIAL_FLUSH) {
1159 _tr_align(s);
1160 } else if (flush == Z_PACKET_FLUSH) {
1161 /* Output just the 3-bit `stored' block type value,
1162 but not a zero length. */
1163 _tr_stored_type_only(s);
1164 } else { /* FULL_FLUSH or SYNC_FLUSH */
1165 _tr_stored_block(s, (char*)0, 0L, 0);
1166 /* For a full flush, this empty block will be recognized
1167 * as a special marker by inflate_sync().
1168 */
1169 if (flush == Z_FULL_FLUSH) {
1170 CLEAR_HASH(s); /* forget history */
1171 }
1172 }
1173 flush_pending(strm);
1174 if (strm->avail_out == 0) {
1175 s->last_flush = -1; /* avoid BUF_ERROR at next call, see above */
1176 return Z_OK;
1177 }
1178 }
1179 }
1180 Assert(strm->avail_out > 0, "bug2");
1181
1182 if (flush != Z_FINISH) return Z_OK;
1183 if (s->noheader) return Z_STREAM_END;
1184
1185 /* Write the zlib trailer (adler32) */
1186 putShortMSB(s, (uInt)(strm->adler >> 16));
1187 putShortMSB(s, (uInt)(strm->adler & 0xffff));
1188 flush_pending(strm);
1189 /* If avail_out is zero, the application will call deflate again
1190 * to flush the rest.
1191 */
1192 s->noheader = -1; /* write the trailer only once! */
1193 return s->pending != 0 ? Z_OK : Z_STREAM_END;
1194 }
1195
1196 /* ========================================================================= */
1197 int ZEXPORT deflateEnd (strm)
1198 z_streamp strm;
1199 {
1200 int status;
1201 deflate_state *s;
1202
1203 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
1204 s = (deflate_state *) strm->state;
1205
1206 status = s->status;
1207 if (status != INIT_STATE && status != BUSY_STATE &&
1208 status != FINISH_STATE) {
1209 return Z_STREAM_ERROR;
1210 }
1211
1212 /* Deallocate in reverse order of allocations: */
1213 TRY_FREE(strm, s->pending_buf);
1214 TRY_FREE(strm, s->head);
1215 TRY_FREE(strm, s->prev);
1216 TRY_FREE(strm, s->window);
1217
1218 ZFREE(strm, s);
1219 strm->state = Z_NULL;
1220
1221 return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK;
1222 }
1223
1224 /* =========================================================================
1225 * Copy the source state to the destination state.
1226 * To simplify the source, this is not supported for 16-bit MSDOS (which
1227 * doesn't have enough memory anyway to duplicate compression states).
1228 */
1229 #if 0
1230 int ZEXPORT deflateCopy (dest, source)
1231 z_streamp dest;
1232 z_streamp source;
1233 {
1234 #ifdef MAXSEG_64K
1235 return Z_STREAM_ERROR;
1236 #else
1237 deflate_state *ds;
1238 deflate_state *ss;
1239 ushf *overlay;
1240
1241
1242 if (source == Z_NULL || dest == Z_NULL || source->state == Z_NULL) {
1243 return Z_STREAM_ERROR;
1244 }
1245
1246 ss = (deflate_state *)source->state;
1247
1248 *dest = *source;
1249
1250 ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state));
1251 if (ds == Z_NULL) return Z_MEM_ERROR;
1252 dest->state = (void *) ds;
1253 *ds = *ss;
1254 ds->strm = dest;
1255
1256 ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte));
1257 ds->prev = (Posf *) ZALLOC(dest, ds->w_size, sizeof(Pos));
1258 ds->head = (Posf *) ZALLOC(dest, ds->hash_size, sizeof(Pos));
1259 overlay = (ushf *) ZALLOC(dest, ds->lit_bufsize, sizeof(ush)+2);
1260 ds->pending_buf = (uchf *) overlay;
1261
1262 if (ds->window == Z_NULL || ds->prev == Z_NULL || ds->head == Z_NULL ||
1263 ds->pending_buf == Z_NULL) {
1264 ds->status = INIT_STATE;
1265 deflateEnd (dest);
1266 return Z_MEM_ERROR;
1267 }
1268 /* following zmemcpy do not work for 16-bit MSDOS */
1269 zmemcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte));
1270 zmemcpy(ds->prev, ss->prev, ds->w_size * sizeof(Pos));
1271 zmemcpy(ds->head, ss->head, ds->hash_size * sizeof(Pos));
1272 zmemcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size);
1273
1274 ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf);
1275 ds->d_buf = overlay + ds->lit_bufsize/sizeof(ush);
1276 ds->l_buf = ds->pending_buf + (1+sizeof(ush))*ds->lit_bufsize;
1277
1278 ds->l_desc.dyn_tree = ds->dyn_ltree;
1279 ds->d_desc.dyn_tree = ds->dyn_dtree;
1280 ds->bl_desc.dyn_tree = ds->bl_tree;
1281
1282 return Z_OK;
1283 #endif
1284 }
1285 #endif
1286
1287 /* ===========================================================================
1288 * Return the number of bytes of output which are immediately available
1289 * for output from the decompressor.
1290 */
1291 #if 0
1292 int deflateOutputPending (strm)
1293 z_streamp strm;
1294 {
1295 if (strm == Z_NULL || strm->state == Z_NULL) return 0;
1296
1297 return ((deflate_state *)(strm->state))->pending;
1298 }
1299 #endif
1300
1301 /* ===========================================================================
1302 * Read a new buffer from the current input stream, update the adler32
1303 * and total number of bytes read. All deflate() input goes through
1304 * this function so some applications may wish to modify it to avoid
1305 * allocating a large strm->next_in buffer and copying from it.
1306 * (See also flush_pending()).
1307 */
1308 local int read_buf(strm, buf, size)
1309 z_streamp strm;
1310 Bytef *buf;
1311 unsigned size;
1312 {
1313 unsigned len = strm->avail_in;
1314
1315 if (len > size) len = size;
1316 if (len == 0) return 0;
1317
1318 strm->avail_in -= len;
1319
1320 if (!((deflate_state *)(strm->state))->noheader) {
1321 strm->adler = adler32(strm->adler, strm->next_in, len);
1322 }
1323 zmemcpy(buf, strm->next_in, len);
1324 strm->next_in += len;
1325 strm->total_in += len;
1326
1327 return (int)len;
1328 }
1329
1330 /* ===========================================================================
1331 * Initialize the "longest match" routines for a new zlib stream
1332 */
1333 local void lm_init (s)
1334 deflate_state *s;
1335 {
1336 s->window_size = (ulg)2L*s->w_size;
1337
1338 CLEAR_HASH(s);
1339
1340 /* Set the default configuration parameters:
1341 */
1342 s->max_lazy_match = configuration_table[s->level].max_lazy;
1343 s->good_match = configuration_table[s->level].good_length;
1344 s->nice_match = configuration_table[s->level].nice_length;
1345 s->max_chain_length = configuration_table[s->level].max_chain;
1346
1347 s->strstart = 0;
1348 s->block_start = 0L;
1349 s->lookahead = 0;
1350 s->match_length = s->prev_length = MIN_MATCH-1;
1351 s->match_available = 0;
1352 s->ins_h = 0;
1353 #ifdef ASMV
1354 match_init(); /* initialize the asm code */
1355 #endif
1356 }
1357
1358 /* ===========================================================================
1359 * Set match_start to the longest match starting at the given string and
1360 * return its length. Matches shorter or equal to prev_length are discarded,
1361 * in which case the result is equal to prev_length and match_start is
1362 * garbage.
1363 * IN assertions: cur_match is the head of the hash chain for the current
1364 * string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1
1365 * OUT assertion: the match length is not greater than s->lookahead.
1366 */
1367 #ifndef ASMV
1368 /* For 80x86 and 680x0, an optimized version will be provided in match.asm or
1369 * match.S. The code will be functionally equivalent.
1370 */
1371 #ifndef FASTEST
1372 local uInt longest_match(s, cur_match)
1373 deflate_state *s;
1374 IPos cur_match; /* current match */
1375 {
1376 unsigned chain_length = s->max_chain_length;/* max hash chain length */
1377 Bytef *scan = s->window + s->strstart; /* current string */
1378 Bytef *match; /* matched string */
1379 int len; /* length of current match */
1380 int best_len = s->prev_length; /* best match length so far */
1381 int nice_match = s->nice_match; /* stop if match long enough */
1382 IPos limit = s->strstart > (IPos)MAX_DIST(s) ?
1383 s->strstart - (IPos)MAX_DIST(s) : NIL;
1384 /* Stop when cur_match becomes <= limit. To simplify the code,
1385 * we prevent matches with the string of window index 0.
1386 */
1387 Posf *prev = s->prev;
1388 uInt wmask = s->w_mask;
1389
1390 #ifdef UNALIGNED_OK
1391 /* Compare two bytes at a time. Note: this is not always beneficial.
1392 * Try with and without -DUNALIGNED_OK to check.
1393 */
1394 Bytef *strend = s->window + s->strstart + MAX_MATCH - 1;
1395 ush scan_start = *(ushf*)scan;
1396 ush scan_end = *(ushf*)(scan+best_len-1);
1397 #else
1398 Bytef *strend = s->window + s->strstart + MAX_MATCH;
1399 Byte scan_end1 = scan[best_len-1];
1400 Byte scan_end = scan[best_len];
1401 #endif
1402
1403 /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
1404 * It is easy to get rid of this optimization if necessary.
1405 */
1406 Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");
1407
1408 /* Do not waste too much time if we already have a good match: */
1409 if (s->prev_length >= s->good_match) {
1410 chain_length >>= 2;
1411 }
1412 /* Do not look for matches beyond the end of the input. This is necessary
1413 * to make deflate deterministic.
1414 */
1415 if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;
1416
1417 Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
1418
1419 do {
1420 Assert(cur_match < s->strstart, "no future");
1421 match = s->window + cur_match;
1422
1423 /* Skip to next match if the match length cannot increase
1424 * or if the match length is less than 2:
1425 */
1426 #if (defined(UNALIGNED_OK) && MAX_MATCH == 258)
1427 /* This code assumes sizeof(unsigned short) == 2. Do not use
1428 * UNALIGNED_OK if your compiler uses a different size.
1429 */
1430 if (*(ushf*)(match+best_len-1) != scan_end ||
1431 *(ushf*)match != scan_start) continue;
1432
1433 /* It is not necessary to compare scan[2] and match[2] since they are
1434 * always equal when the other bytes match, given that the hash keys
1435 * are equal and that HASH_BITS >= 8. Compare 2 bytes at a time at
1436 * strstart+3, +5, ... up to strstart+257. We check for insufficient
1437 * lookahead only every 4th comparison; the 128th check will be made
1438 * at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is
1439 * necessary to put more guard bytes at the end of the window, or
1440 * to check more often for insufficient lookahead.
1441 */
1442 Assert(scan[2] == match[2], "scan[2]?");
1443 scan++, match++;
1444 do {
1445 } while (*(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1446 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1447 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1448 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1449 scan < strend);
1450 /* The funny "do {}" generates better code on most compilers */
1451
1452 /* Here, scan <= window+strstart+257 */
1453 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1454 if (*scan == *match) scan++;
1455
1456 len = (MAX_MATCH - 1) - (int)(strend-scan);
1457 scan = strend - (MAX_MATCH-1);
1458
1459 #else /* UNALIGNED_OK */
1460
1461 if (match[best_len] != scan_end ||
1462 match[best_len-1] != scan_end1 ||
1463 *match != *scan ||
1464 *++match != scan[1]) continue;
1465
1466 /* The check at best_len-1 can be removed because it will be made
1467 * again later. (This heuristic is not always a win.)
1468 * It is not necessary to compare scan[2] and match[2] since they
1469 * are always equal when the other bytes match, given that
1470 * the hash keys are equal and that HASH_BITS >= 8.
1471 */
1472 scan += 2, match++;
1473 Assert(*scan == *match, "match[2]?");
1474
1475 /* We check for insufficient lookahead only every 8th comparison;
1476 * the 256th check will be made at strstart+258.
1477 */
1478 do {
1479 } while (*++scan == *++match && *++scan == *++match &&
1480 *++scan == *++match && *++scan == *++match &&
1481 *++scan == *++match && *++scan == *++match &&
1482 *++scan == *++match && *++scan == *++match &&
1483 scan < strend);
1484
1485 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1486
1487 len = MAX_MATCH - (int)(strend - scan);
1488 scan = strend - MAX_MATCH;
1489
1490 #endif /* UNALIGNED_OK */
1491
1492 if (len > best_len) {
1493 s->match_start = cur_match;
1494 best_len = len;
1495 if (len >= nice_match) break;
1496 #ifdef UNALIGNED_OK
1497 scan_end = *(ushf*)(scan+best_len-1);
1498 #else
1499 scan_end1 = scan[best_len-1];
1500 scan_end = scan[best_len];
1501 #endif
1502 }
1503 } while ((cur_match = prev[cur_match & wmask]) > limit
1504 && --chain_length != 0);
1505
1506 if ((uInt)best_len <= s->lookahead) return (uInt)best_len;
1507 return s->lookahead;
1508 }
1509
1510 #else /* FASTEST */
1511 /* ---------------------------------------------------------------------------
1512 * Optimized version for level == 1 only
1513 */
1514 local uInt longest_match(s, cur_match)
1515 deflate_state *s;
1516 IPos cur_match; /* current match */
1517 {
1518 register Bytef *scan = s->window + s->strstart; /* current string */
1519 register Bytef *match; /* matched string */
1520 register int len; /* length of current match */
1521 register Bytef *strend = s->window + s->strstart + MAX_MATCH;
1522
1523 /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
1524 * It is easy to get rid of this optimization if necessary.
1525 */
1526 Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");
1527
1528 Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
1529
1530 Assert(cur_match < s->strstart, "no future");
1531
1532 match = s->window + cur_match;
1533
1534 /* Return failure if the match length is less than 2:
1535 */
1536 if (match[0] != scan[0] || match[1] != scan[1]) return MIN_MATCH-1;
1537
1538 /* The check at best_len-1 can be removed because it will be made
1539 * again later. (This heuristic is not always a win.)
1540 * It is not necessary to compare scan[2] and match[2] since they
1541 * are always equal when the other bytes match, given that
1542 * the hash keys are equal and that HASH_BITS >= 8.
1543 */
1544 scan += 2, match += 2;
1545 Assert(*scan == *match, "match[2]?");
1546
1547 /* We check for insufficient lookahead only every 8th comparison;
1548 * the 256th check will be made at strstart+258.
1549 */
1550 do {
1551 } while (*++scan == *++match && *++scan == *++match &&
1552 *++scan == *++match && *++scan == *++match &&
1553 *++scan == *++match && *++scan == *++match &&
1554 *++scan == *++match && *++scan == *++match &&
1555 scan < strend);
1556
1557 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1558
1559 len = MAX_MATCH - (int)(strend - scan);
1560
1561 if (len < MIN_MATCH) return MIN_MATCH - 1;
1562
1563 s->match_start = cur_match;
1564 return len <= s->lookahead ? len : s->lookahead;
1565 }
1566 #endif /* FASTEST */
1567 #endif /* ASMV */
1568
1569 #ifdef DEBUG_ZLIB
1570 /* ===========================================================================
1571 * Check that the match at match_start is indeed a match.
1572 */
1573 local void check_match(s, start, match, length)
1574 deflate_state *s;
1575 IPos start, match;
1576 int length;
1577 {
1578 /* check that the match is indeed a match */
1579 if (zmemcmp(s->window + match,
1580 s->window + start, length) != EQUAL) {
1581 fprintf(stderr, " start %u, match %u, length %d\n",
1582 start, match, length);
1583 do {
1584 fprintf(stderr, "%c%c", s->window[match++], s->window[start++]);
1585 } while (--length != 0);
1586 z_error("invalid match");
1587 }
1588 if (z_verbose > 1) {
1589 fprintf(stderr,"\\[%d,%d]", start-match, length);
1590 do { putc(s->window[start++], stderr); } while (--length != 0);
1591 }
1592 }
1593 #else
1594 # define check_match(s, start, match, length)
1595 #endif
1596
1597 /* ===========================================================================
1598 * Fill the window when the lookahead becomes insufficient.
1599 * Updates strstart and lookahead.
1600 *
1601 * IN assertion: lookahead < MIN_LOOKAHEAD
1602 * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD
1603 * At least one byte has been read, or avail_in == 0; reads are
1604 * performed for at least two bytes (required for the zip translate_eol
1605 * option -- not supported here).
1606 */
1607 local void fill_window(s)
1608 deflate_state *s;
1609 {
1610 unsigned n, m;
1611 Posf *p;
1612 unsigned more; /* Amount of free space at the end of the window. */
1613 uInt wsize = s->w_size;
1614
1615 do {
1616 more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart);
1617
1618 /* Deal with !@#$% 64K limit: */
1619 if (more == 0 && s->strstart == 0 && s->lookahead == 0) {
1620 more = wsize;
1621
1622 } else if (more == (unsigned)(-1)) {
1623 /* Very unlikely, but possible on 16 bit machine if strstart == 0
1624 * and lookahead == 1 (input done one byte at time)
1625 */
1626 more--;
1627
1628 /* If the window is almost full and there is insufficient lookahead,
1629 * move the upper half to the lower one to make room in the upper half.
1630 */
1631 } else if (s->strstart >= wsize+MAX_DIST(s)) {
1632
1633 zmemcpy(s->window, s->window+wsize, (unsigned)wsize);
1634 s->match_start -= wsize;
1635 s->strstart -= wsize; /* we now have strstart >= MAX_DIST */
1636 s->block_start -= (long) wsize;
1637
1638 /* Slide the hash table (could be avoided with 32 bit values
1639 at the expense of memory usage). We slide even when level == 0
1640 to keep the hash table consistent if we switch back to level > 0
1641 later. (Using level 0 permanently is not an optimal usage of
1642 zlib, so we don't care about this pathological case.)
1643 */
1644 n = s->hash_size;
1645 p = &s->head[n];
1646 do {
1647 m = *--p;
1648 *p = (Pos)(m >= wsize ? m-wsize : NIL);
1649 } while (--n);
1650
1651 n = wsize;
1652 #ifndef FASTEST
1653 p = &s->prev[n];
1654 do {
1655 m = *--p;
1656 *p = (Pos)(m >= wsize ? m-wsize : NIL);
1657 /* If n is not on any hash chain, prev[n] is garbage but
1658 * its value will never be used.
1659 */
1660 } while (--n);
1661 #endif
1662 more += wsize;
1663 }
1664 if (s->strm->avail_in == 0) return;
1665
1666 /* If there was no sliding:
1667 * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 &&
1668 * more == window_size - lookahead - strstart
1669 * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1)
1670 * => more >= window_size - 2*WSIZE + 2
1671 * In the BIG_MEM or MMAP case (not yet supported),
1672 * window_size == input_size + MIN_LOOKAHEAD &&
1673 * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD.
1674 * Otherwise, window_size == 2*WSIZE so more >= 2.
1675 * If there was sliding, more >= WSIZE. So in all cases, more >= 2.
1676 */
1677 Assert(more >= 2, "more < 2");
1678
1679 n = read_buf(s->strm, s->window + s->strstart + s->lookahead, more);
1680 s->lookahead += n;
1681
1682 /* Initialize the hash value now that we have some input: */
1683 if (s->lookahead >= MIN_MATCH) {
1684 s->ins_h = s->window[s->strstart];
1685 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
1686 #if MIN_MATCH != 3
1687 Call UPDATE_HASH() MIN_MATCH-3 more times
1688 #endif
1689 }
1690 /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage,
1691 * but this is not important since only literal bytes will be emitted.
1692 */
1693
1694 } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0);
1695 }
1696
1697 /* ===========================================================================
1698 * Flush the current block, with given end-of-file flag.
1699 * IN assertion: strstart is set to the end of the current match.
1700 */
1701 #define FLUSH_BLOCK_ONLY(s, eof) { \
1702 _tr_flush_block(s, (s->block_start >= 0L ? \
1703 (charf *)&s->window[(unsigned)s->block_start] : \
1704 (charf *)Z_NULL), \
1705 (ulg)((long)s->strstart - s->block_start), \
1706 (eof)); \
1707 s->block_start = s->strstart; \
1708 flush_pending(s->strm); \
1709 Tracev((stderr,"[FLUSH]")); \
1710 }
1711
1712 /* Same but force premature exit if necessary. */
1713 #define FLUSH_BLOCK(s, eof) { \
1714 FLUSH_BLOCK_ONLY(s, eof); \
1715 if (s->strm->avail_out == 0) return (eof) ? finish_started : need_more; \
1716 }
1717
1718 /* ===========================================================================
1719 * Copy without compression as much as possible from the input stream, return
1720 * the current block state.
1721 * This function does not insert new strings in the dictionary since
1722 * uncompressible data is probably not useful. This function is used
1723 * only for the level=0 compression option.
1724 * NOTE: this function should be optimized to avoid extra copying from
1725 * window to pending_buf.
1726 */
1727 local block_state deflate_stored(s, flush)
1728 deflate_state *s;
1729 int flush;
1730 {
1731 /* Stored blocks are limited to 0xffff bytes, pending_buf is limited
1732 * to pending_buf_size, and each stored block has a 5 byte header:
1733 */
1734 ulg max_block_size = 0xffff;
1735 ulg max_start;
1736
1737 if (max_block_size > s->pending_buf_size - 5) {
1738 max_block_size = s->pending_buf_size - 5;
1739 }
1740
1741 /* Copy as much as possible from input to output: */
1742 for (;;) {
1743 /* Fill the window as much as possible: */
1744 if (s->lookahead <= 1) {
1745
1746 Assert(s->strstart < s->w_size+MAX_DIST(s) ||
1747 s->block_start >= (long)s->w_size, "slide too late");
1748
1749 fill_window(s);
1750 if (s->lookahead == 0 && flush == Z_NO_FLUSH) return need_more;
1751
1752 if (s->lookahead == 0) break; /* flush the current block */
1753 }
1754 Assert(s->block_start >= 0L, "block gone");
1755
1756 s->strstart += s->lookahead;
1757 s->lookahead = 0;
1758
1759 /* Emit a stored block if pending_buf will be full: */
1760 max_start = s->block_start + max_block_size;
1761 if (s->strstart == 0 || (ulg)s->strstart >= max_start) {
1762 /* strstart == 0 is possible when wraparound on 16-bit machine */
1763 s->lookahead = (uInt)(s->strstart - max_start);
1764 s->strstart = (uInt)max_start;
1765 FLUSH_BLOCK(s, 0);
1766 }
1767 /* Flush if we may have to slide, otherwise block_start may become
1768 * negative and the data will be gone:
1769 */
1770 if (s->strstart - (uInt)s->block_start >= MAX_DIST(s)) {
1771 FLUSH_BLOCK(s, 0);
1772 }
1773 }
1774 FLUSH_BLOCK(s, flush == Z_FINISH);
1775 return flush == Z_FINISH ? finish_done : block_done;
1776 }
1777
1778 /* ===========================================================================
1779 * Compress as much as possible from the input stream, return the current
1780 * block state.
1781 * This function does not perform lazy evaluation of matches and inserts
1782 * new strings in the dictionary only for unmatched strings or for short
1783 * matches. It is used only for the fast compression options.
1784 */
1785 local block_state deflate_fast(s, flush)
1786 deflate_state *s;
1787 int flush;
1788 {
1789 IPos hash_head = NIL; /* head of the hash chain */
1790 int bflush; /* set if current block must be flushed */
1791
1792 for (;;) {
1793 /* Make sure that we always have enough lookahead, except
1794 * at the end of the input file. We need MAX_MATCH bytes
1795 * for the next match, plus MIN_MATCH bytes to insert the
1796 * string following the next match.
1797 */
1798 if (s->lookahead < MIN_LOOKAHEAD) {
1799 fill_window(s);
1800 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
1801 return need_more;
1802 }
1803 if (s->lookahead == 0) break; /* flush the current block */
1804 }
1805
1806 /* Insert the string window[strstart .. strstart+2] in the
1807 * dictionary, and set hash_head to the head of the hash chain:
1808 */
1809 if (s->lookahead >= MIN_MATCH) {
1810 INSERT_STRING(s, s->strstart, hash_head);
1811 }
1812
1813 /* Find the longest match, discarding those <= prev_length.
1814 * At this point we have always match_length < MIN_MATCH
1815 */
1816 if (hash_head != NIL && s->strstart - hash_head <= MAX_DIST(s)) {
1817 /* To simplify the code, we prevent matches with the string
1818 * of window index 0 (in particular we have to avoid a match
1819 * of the string with itself at the start of the input file).
1820 */
1821 if (s->strategy != Z_HUFFMAN_ONLY) {
1822 s->match_length = longest_match (s, hash_head);
1823 }
1824 /* longest_match() sets match_start */
1825 }
1826 if (s->match_length >= MIN_MATCH) {
1827 check_match(s, s->strstart, s->match_start, s->match_length);
1828
1829 _tr_tally_dist(s, s->strstart - s->match_start,
1830 s->match_length - MIN_MATCH, bflush);
1831
1832 s->lookahead -= s->match_length;
1833
1834 /* Insert new strings in the hash table only if the match length
1835 * is not too large. This saves time but degrades compression.
1836 */
1837 #ifndef FASTEST
1838 if (s->match_length <= s->max_insert_length &&
1839 s->lookahead >= MIN_MATCH) {
1840 s->match_length--; /* string at strstart already in hash table */
1841 do {
1842 s->strstart++;
1843 INSERT_STRING(s, s->strstart, hash_head);
1844 /* strstart never exceeds WSIZE-MAX_MATCH, so there are
1845 * always MIN_MATCH bytes ahead.
1846 */
1847 } while (--s->match_length != 0);
1848 s->strstart++;
1849 } else
1850 #endif
1851 {
1852 s->strstart += s->match_length;
1853 s->match_length = 0;
1854 s->ins_h = s->window[s->strstart];
1855 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
1856 #if MIN_MATCH != 3
1857 Call UPDATE_HASH() MIN_MATCH-3 more times
1858 #endif
1859 /* If lookahead < MIN_MATCH, ins_h is garbage, but it does not
1860 * matter since it will be recomputed at next deflate call.
1861 */
1862 }
1863 } else {
1864 /* No match, output a literal byte */
1865 Tracevv((stderr,"%c", s->window[s->strstart]));
1866 _tr_tally_lit (s, s->window[s->strstart], bflush);
1867 s->lookahead--;
1868 s->strstart++;
1869 }
1870 if (bflush) FLUSH_BLOCK(s, 0);
1871 }
1872 FLUSH_BLOCK(s, flush == Z_FINISH);
1873 return flush == Z_FINISH ? finish_done : block_done;
1874 }
1875
1876 /* ===========================================================================
1877 * Same as above, but achieves better compression. We use a lazy
1878 * evaluation for matches: a match is finally adopted only if there is
1879 * no better match at the next window position.
1880 */
1881 local block_state deflate_slow(s, flush)
1882 deflate_state *s;
1883 int flush;
1884 {
1885 IPos hash_head = NIL; /* head of hash chain */
1886 int bflush; /* set if current block must be flushed */
1887
1888 /* Process the input block. */
1889 for (;;) {
1890 /* Make sure that we always have enough lookahead, except
1891 * at the end of the input file. We need MAX_MATCH bytes
1892 * for the next match, plus MIN_MATCH bytes to insert the
1893 * string following the next match.
1894 */
1895 if (s->lookahead < MIN_LOOKAHEAD) {
1896 fill_window(s);
1897 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
1898 return need_more;
1899 }
1900 if (s->lookahead == 0) break; /* flush the current block */
1901 }
1902
1903 /* Insert the string window[strstart .. strstart+2] in the
1904 * dictionary, and set hash_head to the head of the hash chain:
1905 */
1906 if (s->lookahead >= MIN_MATCH) {
1907 INSERT_STRING(s, s->strstart, hash_head);
1908 }
1909
1910 /* Find the longest match, discarding those <= prev_length.
1911 */
1912 s->prev_length = s->match_length, s->prev_match = s->match_start;
1913 s->match_length = MIN_MATCH-1;
1914
1915 if (hash_head != NIL && s->prev_length < s->max_lazy_match &&
1916 s->strstart - hash_head <= MAX_DIST(s)) {
1917 /* To simplify the code, we prevent matches with the string
1918 * of window index 0 (in particular we have to avoid a match
1919 * of the string with itself at the start of the input file).
1920 */
1921 if (s->strategy != Z_HUFFMAN_ONLY) {
1922 s->match_length = longest_match (s, hash_head);
1923 }
1924 /* longest_match() sets match_start */
1925
1926 if (s->match_length <= 5 && (s->strategy == Z_FILTERED ||
1927 (s->match_length == MIN_MATCH &&
1928 s->strstart - s->match_start > TOO_FAR))) {
1929
1930 /* If prev_match is also MIN_MATCH, match_start is garbage
1931 * but we will ignore the current match anyway.
1932 */
1933 s->match_length = MIN_MATCH-1;
1934 }
1935 }
1936 /* If there was a match at the previous step and the current
1937 * match is not better, output the previous match:
1938 */
1939 if (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) {
1940 uInt max_insert = s->strstart + s->lookahead - MIN_MATCH;
1941 /* Do not insert strings in hash table beyond this. */
1942
1943 check_match(s, s->strstart-1, s->prev_match, s->prev_length);
1944
1945 _tr_tally_dist(s, s->strstart -1 - s->prev_match,
1946 s->prev_length - MIN_MATCH, bflush);
1947
1948 /* Insert in hash table all strings up to the end of the match.
1949 * strstart-1 and strstart are already inserted. If there is not
1950 * enough lookahead, the last two strings are not inserted in
1951 * the hash table.
1952 */
1953 s->lookahead -= s->prev_length-1;
1954 s->prev_length -= 2;
1955 do {
1956 if (++s->strstart <= max_insert) {
1957 INSERT_STRING(s, s->strstart, hash_head);
1958 }
1959 } while (--s->prev_length != 0);
1960 s->match_available = 0;
1961 s->match_length = MIN_MATCH-1;
1962 s->strstart++;
1963
1964 if (bflush) FLUSH_BLOCK(s, 0);
1965
1966 } else if (s->match_available) {
1967 /* If there was no match at the previous position, output a
1968 * single literal. If there was a match but the current match
1969 * is longer, truncate the previous match to a single literal.
1970 */
1971 Tracevv((stderr,"%c", s->window[s->strstart-1]));
1972 _tr_tally_lit(s, s->window[s->strstart-1], bflush);
1973 if (bflush) {
1974 FLUSH_BLOCK_ONLY(s, 0);
1975 }
1976 s->strstart++;
1977 s->lookahead--;
1978 if (s->strm->avail_out == 0) return need_more;
1979 } else {
1980 /* There is no previous match to compare with, wait for
1981 * the next step to decide.
1982 */
1983 s->match_available = 1;
1984 s->strstart++;
1985 s->lookahead--;
1986 }
1987 }
1988 Assert (flush != Z_NO_FLUSH, "no flush?");
1989 if (s->match_available) {
1990 Tracevv((stderr,"%c", s->window[s->strstart-1]));
1991 _tr_tally_lit(s, s->window[s->strstart-1], bflush);
1992 s->match_available = 0;
1993 }
1994 FLUSH_BLOCK(s, flush == Z_FINISH);
1995 return flush == Z_FINISH ? finish_done : block_done;
1996 }
1997 /* --- deflate.c */
1998
1999 /* +++ trees.c */
2000
2001 /* trees.c -- output deflated data using Huffman coding
2002 * Copyright (C) 1995-2002 Jean-loup Gailly
2003 * For conditions of distribution and use, see copyright notice in zlib.h
2004 */
2005
2006 /*
2007 * ALGORITHM
2008 *
2009 * The "deflation" process uses several Huffman trees. The more
2010 * common source values are represented by shorter bit sequences.
2011 *
2012 * Each code tree is stored in a compressed form which is itself
2013 * a Huffman encoding of the lengths of all the code strings (in
2014 * ascending order by source values). The actual code strings are
2015 * reconstructed from the lengths in the inflate process, as described
2016 * in the deflate specification.
2017 *
2018 * REFERENCES
2019 *
2020 * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification".
2021 * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc
2022 *
2023 * Storer, James A.
2024 * Data Compression: Methods and Theory, pp. 49-50.
2025 * Computer Science Press, 1988. ISBN 0-7167-8156-5.
2026 *
2027 * Sedgewick, R.
2028 * Algorithms, p290.
2029 * Addison-Wesley, 1983. ISBN 0-201-06672-6.
2030 */
2031
2032 /* @(#) $Id: zlib.c,v 1.19 2002/08/20 03:52:26 kristerw Exp $ */
2033
2034 /* #define GEN_TREES_H */
2035
2036 /* #include "deflate.h" */
2037
2038 #ifdef DEBUG_ZLIB
2039 # include <ctype.h>
2040 #endif
2041
2042 /* ===========================================================================
2043 * Constants
2044 */
2045
2046 #define MAX_BL_BITS 7
2047 /* Bit length codes must not exceed MAX_BL_BITS bits */
2048
2049 #define END_BLOCK 256
2050 /* end of block literal code */
2051
2052 #define REP_3_6 16
2053 /* repeat previous bit length 3-6 times (2 bits of repeat count) */
2054
2055 #define REPZ_3_10 17
2056 /* repeat a zero length 3-10 times (3 bits of repeat count) */
2057
2058 #define REPZ_11_138 18
2059 /* repeat a zero length 11-138 times (7 bits of repeat count) */
2060
2061 local const int extra_lbits[LENGTH_CODES] /* extra bits for each length code */
2062 = {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};
2063
2064 local const int extra_dbits[D_CODES] /* extra bits for each distance code */
2065 = {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};
2066
2067 local const int extra_blbits[BL_CODES]/* extra bits for each bit length code */
2068 = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7};
2069
2070 local const uch bl_order[BL_CODES]
2071 = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15};
2072 /* The lengths of the bit length codes are sent in order of decreasing
2073 * probability, to avoid transmitting the lengths for unused bit length codes.
2074 */
2075
2076 #define Buf_size (8 * 2*sizeof(char))
2077 /* Number of bits used within bi_buf. (bi_buf might be implemented on
2078 * more than 16 bits on some systems.)
2079 */
2080
2081 /* ===========================================================================
2082 * Local data. These are initialized only once.
2083 */
2084
2085 #define DIST_CODE_LEN 512 /* see definition of array dist_code below */
2086
2087 #if defined(GEN_TREES_H) || !defined(STDC)
2088 /* non ANSI compilers may not accept trees.h */
2089
2090 local ct_data static_ltree[L_CODES+2];
2091 /* The static literal tree. Since the bit lengths are imposed, there is no
2092 * need for the L_CODES extra codes used during heap construction. However
2093 * The codes 286 and 287 are needed to build a canonical tree (see _tr_init
2094 * below).
2095 */
2096
2097 local ct_data static_dtree[D_CODES];
2098 /* The static distance tree. (Actually a trivial tree since all codes use
2099 * 5 bits.)
2100 */
2101
2102 uch _dist_code[DIST_CODE_LEN];
2103 /* Distance codes. The first 256 values correspond to the distances
2104 * 3 .. 258, the last 256 values correspond to the top 8 bits of
2105 * the 15 bit distances.
2106 */
2107
2108 uch _length_code[MAX_MATCH-MIN_MATCH+1];
2109 /* length code for each normalized match length (0 == MIN_MATCH) */
2110
2111 local int base_length[LENGTH_CODES];
2112 /* First normalized length for each code (0 = MIN_MATCH) */
2113
2114 local int base_dist[D_CODES];
2115 /* First normalized distance for each code (0 = distance of 1) */
2116
2117 #else
2118 /* +++ trees.h */
2119
2120 /* header created automatically with -DGEN_TREES_H */
2121
2122 local const ct_data static_ltree[L_CODES+2] = {
2123 {{ 12},{ 8}}, {{140},{ 8}}, {{ 76},{ 8}}, {{204},{ 8}}, {{ 44},{ 8}},
2124 {{172},{ 8}}, {{108},{ 8}}, {{236},{ 8}}, {{ 28},{ 8}}, {{156},{ 8}},
2125 {{ 92},{ 8}}, {{220},{ 8}}, {{ 60},{ 8}}, {{188},{ 8}}, {{124},{ 8}},
2126 {{252},{ 8}}, {{ 2},{ 8}}, {{130},{ 8}}, {{ 66},{ 8}}, {{194},{ 8}},
2127 {{ 34},{ 8}}, {{162},{ 8}}, {{ 98},{ 8}}, {{226},{ 8}}, {{ 18},{ 8}},
2128 {{146},{ 8}}, {{ 82},{ 8}}, {{210},{ 8}}, {{ 50},{ 8}}, {{178},{ 8}},
2129 {{114},{ 8}}, {{242},{ 8}}, {{ 10},{ 8}}, {{138},{ 8}}, {{ 74},{ 8}},
2130 {{202},{ 8}}, {{ 42},{ 8}}, {{170},{ 8}}, {{106},{ 8}}, {{234},{ 8}},
2131 {{ 26},{ 8}}, {{154},{ 8}}, {{ 90},{ 8}}, {{218},{ 8}}, {{ 58},{ 8}},
2132 {{186},{ 8}}, {{122},{ 8}}, {{250},{ 8}}, {{ 6},{ 8}}, {{134},{ 8}},
2133 {{ 70},{ 8}}, {{198},{ 8}}, {{ 38},{ 8}}, {{166},{ 8}}, {{102},{ 8}},
2134 {{230},{ 8}}, {{ 22},{ 8}}, {{150},{ 8}}, {{ 86},{ 8}}, {{214},{ 8}},
2135 {{ 54},{ 8}}, {{182},{ 8}}, {{118},{ 8}}, {{246},{ 8}}, {{ 14},{ 8}},
2136 {{142},{ 8}}, {{ 78},{ 8}}, {{206},{ 8}}, {{ 46},{ 8}}, {{174},{ 8}},
2137 {{110},{ 8}}, {{238},{ 8}}, {{ 30},{ 8}}, {{158},{ 8}}, {{ 94},{ 8}},
2138 {{222},{ 8}}, {{ 62},{ 8}}, {{190},{ 8}}, {{126},{ 8}}, {{254},{ 8}},
2139 {{ 1},{ 8}}, {{129},{ 8}}, {{ 65},{ 8}}, {{193},{ 8}}, {{ 33},{ 8}},
2140 {{161},{ 8}}, {{ 97},{ 8}}, {{225},{ 8}}, {{ 17},{ 8}}, {{145},{ 8}},
2141 {{ 81},{ 8}}, {{209},{ 8}}, {{ 49},{ 8}}, {{177},{ 8}}, {{113},{ 8}},
2142 {{241},{ 8}}, {{ 9},{ 8}}, {{137},{ 8}}, {{ 73},{ 8}}, {{201},{ 8}},
2143 {{ 41},{ 8}}, {{169},{ 8}}, {{105},{ 8}}, {{233},{ 8}}, {{ 25},{ 8}},
2144 {{153},{ 8}}, {{ 89},{ 8}}, {{217},{ 8}}, {{ 57},{ 8}}, {{185},{ 8}},
2145 {{121},{ 8}}, {{249},{ 8}}, {{ 5},{ 8}}, {{133},{ 8}}, {{ 69},{ 8}},
2146 {{197},{ 8}}, {{ 37},{ 8}}, {{165},{ 8}}, {{101},{ 8}}, {{229},{ 8}},
2147 {{ 21},{ 8}}, {{149},{ 8}}, {{ 85},{ 8}}, {{213},{ 8}}, {{ 53},{ 8}},
2148 {{181},{ 8}}, {{117},{ 8}}, {{245},{ 8}}, {{ 13},{ 8}}, {{141},{ 8}},
2149 {{ 77},{ 8}}, {{205},{ 8}}, {{ 45},{ 8}}, {{173},{ 8}}, {{109},{ 8}},
2150 {{237},{ 8}}, {{ 29},{ 8}}, {{157},{ 8}}, {{ 93},{ 8}}, {{221},{ 8}},
2151 {{ 61},{ 8}}, {{189},{ 8}}, {{125},{ 8}}, {{253},{ 8}}, {{ 19},{ 9}},
2152 {{275},{ 9}}, {{147},{ 9}}, {{403},{ 9}}, {{ 83},{ 9}}, {{339},{ 9}},
2153 {{211},{ 9}}, {{467},{ 9}}, {{ 51},{ 9}}, {{307},{ 9}}, {{179},{ 9}},
2154 {{435},{ 9}}, {{115},{ 9}}, {{371},{ 9}}, {{243},{ 9}}, {{499},{ 9}},
2155 {{ 11},{ 9}}, {{267},{ 9}}, {{139},{ 9}}, {{395},{ 9}}, {{ 75},{ 9}},
2156 {{331},{ 9}}, {{203},{ 9}}, {{459},{ 9}}, {{ 43},{ 9}}, {{299},{ 9}},
2157 {{171},{ 9}}, {{427},{ 9}}, {{107},{ 9}}, {{363},{ 9}}, {{235},{ 9}},
2158 {{491},{ 9}}, {{ 27},{ 9}}, {{283},{ 9}}, {{155},{ 9}}, {{411},{ 9}},
2159 {{ 91},{ 9}}, {{347},{ 9}}, {{219},{ 9}}, {{475},{ 9}}, {{ 59},{ 9}},
2160 {{315},{ 9}}, {{187},{ 9}}, {{443},{ 9}}, {{123},{ 9}}, {{379},{ 9}},
2161 {{251},{ 9}}, {{507},{ 9}}, {{ 7},{ 9}}, {{263},{ 9}}, {{135},{ 9}},
2162 {{391},{ 9}}, {{ 71},{ 9}}, {{327},{ 9}}, {{199},{ 9}}, {{455},{ 9}},
2163 {{ 39},{ 9}}, {{295},{ 9}}, {{167},{ 9}}, {{423},{ 9}}, {{103},{ 9}},
2164 {{359},{ 9}}, {{231},{ 9}}, {{487},{ 9}}, {{ 23},{ 9}}, {{279},{ 9}},
2165 {{151},{ 9}}, {{407},{ 9}}, {{ 87},{ 9}}, {{343},{ 9}}, {{215},{ 9}},
2166 {{471},{ 9}}, {{ 55},{ 9}}, {{311},{ 9}}, {{183},{ 9}}, {{439},{ 9}},
2167 {{119},{ 9}}, {{375},{ 9}}, {{247},{ 9}}, {{503},{ 9}}, {{ 15},{ 9}},
2168 {{271},{ 9}}, {{143},{ 9}}, {{399},{ 9}}, {{ 79},{ 9}}, {{335},{ 9}},
2169 {{207},{ 9}}, {{463},{ 9}}, {{ 47},{ 9}}, {{303},{ 9}}, {{175},{ 9}},
2170 {{431},{ 9}}, {{111},{ 9}}, {{367},{ 9}}, {{239},{ 9}}, {{495},{ 9}},
2171 {{ 31},{ 9}}, {{287},{ 9}}, {{159},{ 9}}, {{415},{ 9}}, {{ 95},{ 9}},
2172 {{351},{ 9}}, {{223},{ 9}}, {{479},{ 9}}, {{ 63},{ 9}}, {{319},{ 9}},
2173 {{191},{ 9}}, {{447},{ 9}}, {{127},{ 9}}, {{383},{ 9}}, {{255},{ 9}},
2174 {{511},{ 9}}, {{ 0},{ 7}}, {{ 64},{ 7}}, {{ 32},{ 7}}, {{ 96},{ 7}},
2175 {{ 16},{ 7}}, {{ 80},{ 7}}, {{ 48},{ 7}}, {{112},{ 7}}, {{ 8},{ 7}},
2176 {{ 72},{ 7}}, {{ 40},{ 7}}, {{104},{ 7}}, {{ 24},{ 7}}, {{ 88},{ 7}},
2177 {{ 56},{ 7}}, {{120},{ 7}}, {{ 4},{ 7}}, {{ 68},{ 7}}, {{ 36},{ 7}},
2178 {{100},{ 7}}, {{ 20},{ 7}}, {{ 84},{ 7}}, {{ 52},{ 7}}, {{116},{ 7}},
2179 {{ 3},{ 8}}, {{131},{ 8}}, {{ 67},{ 8}}, {{195},{ 8}}, {{ 35},{ 8}},
2180 {{163},{ 8}}, {{ 99},{ 8}}, {{227},{ 8}}
2181 };
2182
2183 local const ct_data static_dtree[D_CODES] = {
2184 {{ 0},{ 5}}, {{16},{ 5}}, {{ 8},{ 5}}, {{24},{ 5}}, {{ 4},{ 5}},
2185 {{20},{ 5}}, {{12},{ 5}}, {{28},{ 5}}, {{ 2},{ 5}}, {{18},{ 5}},
2186 {{10},{ 5}}, {{26},{ 5}}, {{ 6},{ 5}}, {{22},{ 5}}, {{14},{ 5}},
2187 {{30},{ 5}}, {{ 1},{ 5}}, {{17},{ 5}}, {{ 9},{ 5}}, {{25},{ 5}},
2188 {{ 5},{ 5}}, {{21},{ 5}}, {{13},{ 5}}, {{29},{ 5}}, {{ 3},{ 5}},
2189 {{19},{ 5}}, {{11},{ 5}}, {{27},{ 5}}, {{ 7},{ 5}}, {{23},{ 5}}
2190 };
2191
2192 const uch _dist_code[DIST_CODE_LEN] = {
2193 0, 1, 2, 3, 4, 4, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8, 8,
2194 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 10,
2195 10, 10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11,
2196 11, 11, 11, 11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
2197 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 13, 13, 13, 13,
2198 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13,
2199 13, 13, 13, 13, 13, 13, 13, 13, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
2200 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
2201 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
2202 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 15, 15, 15, 15, 15, 15, 15, 15,
2203 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
2204 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
2205 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 0, 0, 16, 17,
2206 18, 18, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 22, 22, 22, 22, 22, 22, 22, 22,
2207 23, 23, 23, 23, 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
2208 24, 24, 24, 24, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
2209 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
2210 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 27, 27, 27, 27, 27, 27, 27, 27,
2211 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
2212 27, 27, 27, 27, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
2213 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
2214 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
2215 28, 28, 28, 28, 28, 28, 28, 28, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
2216 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
2217 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
2218 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29
2219 };
2220
2221 const uch _length_code[MAX_MATCH-MIN_MATCH+1]= {
2222 0, 1, 2, 3, 4, 5, 6, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 12, 12,
2223 13, 13, 13, 13, 14, 14, 14, 14, 15, 15, 15, 15, 16, 16, 16, 16, 16, 16, 16, 16,
2224 17, 17, 17, 17, 17, 17, 17, 17, 18, 18, 18, 18, 18, 18, 18, 18, 19, 19, 19, 19,
2225 19, 19, 19, 19, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20,
2226 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 22, 22, 22, 22,
2227 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 23, 23, 23, 23, 23, 23, 23, 23,
2228 23, 23, 23, 23, 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
2229 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
2230 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
2231 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 26, 26, 26, 26, 26, 26, 26, 26,
2232 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
2233 26, 26, 26, 26, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
2234 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 28
2235 };
2236
2237 local const int base_length[LENGTH_CODES] = {
2238 0, 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, 16, 20, 24, 28, 32, 40, 48, 56,
2239 64, 80, 96, 112, 128, 160, 192, 224, 0
2240 };
2241
2242 local const int base_dist[D_CODES] = {
2243 0, 1, 2, 3, 4, 6, 8, 12, 16, 24,
2244 32, 48, 64, 96, 128, 192, 256, 384, 512, 768,
2245 1024, 1536, 2048, 3072, 4096, 6144, 8192, 12288, 16384, 24576
2246 };
2247 /* --- trees.h */
2248
2249 #endif /* GEN_TREES_H */
2250
2251 struct static_tree_desc_s {
2252 const ct_data *static_tree; /* static tree or NULL */
2253 const intf *extra_bits; /* extra bits for each code or NULL */
2254 int extra_base; /* base index for extra_bits */
2255 int elems; /* max number of elements in the tree */
2256 int max_length; /* max bit length for the codes */
2257 };
2258
2259 local static_tree_desc static_l_desc =
2260 {static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS};
2261
2262 local static_tree_desc static_d_desc =
2263 {static_dtree, extra_dbits, 0, D_CODES, MAX_BITS};
2264
2265 local static_tree_desc static_bl_desc =
2266 {(const ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS};
2267
2268 /* ===========================================================================
2269 * Local (static) routines in this file.
2270 */
2271
2272 local void tr_static_init __P((void));
2273 local void init_block __P((deflate_state *s));
2274 local void pqdownheap __P((deflate_state *s, ct_data *tree, int k));
2275 local void gen_bitlen __P((deflate_state *s, tree_desc *desc));
2276 local void gen_codes __P((ct_data *tree, int max_code, ushf *bl_count));
2277 local void build_tree __P((deflate_state *s, tree_desc *desc));
2278 local void scan_tree __P((deflate_state *s, ct_data *tree, int max_code));
2279 local void send_tree __P((deflate_state *s, ct_data *tree, int max_code));
2280 local int build_bl_tree __P((deflate_state *s));
2281 local void send_all_trees __P((deflate_state *s, int lcodes, int dcodes,
2282 int blcodes));
2283 local void compress_block __P((deflate_state *s, ct_data *ltree,
2284 ct_data *dtree));
2285 local void set_data_type __P((deflate_state *s));
2286 local unsigned bi_reverse __P((unsigned value, int length));
2287 local void bi_windup __P((deflate_state *s));
2288 local void bi_flush __P((deflate_state *s));
2289 local void copy_block __P((deflate_state *s, charf *buf, unsigned len,
2290 int header));
2291
2292 #ifdef GEN_TREES_H
2293 local void gen_trees_header __P((void));
2294 #endif
2295
2296 #ifndef DEBUG_ZLIB
2297 # define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len)
2298 /* Send a code of the given tree. c and tree must not have side effects */
2299
2300 #else /* DEBUG_ZLIB */
2301 # define send_code(s, c, tree) \
2302 { if (z_verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \
2303 send_bits(s, tree[c].Code, tree[c].Len); }
2304 #endif
2305
2306 /* ===========================================================================
2307 * Output a short LSB first on the stream.
2308 * IN assertion: there is enough room in pendingBuf.
2309 */
2310 #define put_short(s, w) { \
2311 put_byte(s, (uch)((w) & 0xff)); \
2312 put_byte(s, (uch)((ush)(w) >> 8)); \
2313 }
2314
2315 /* ===========================================================================
2316 * Send a value on a given number of bits.
2317 * IN assertion: length <= 16 and value fits in length bits.
2318 */
2319 #ifdef DEBUG_ZLIB
2320 local void send_bits __P((deflate_state *s, int value, int length));
2321
2322 local void send_bits(s, value, length)
2323 deflate_state *s;
2324 int value; /* value to send */
2325 int length; /* number of bits */
2326 {
2327 Tracevv((stderr," l %2d v %4x ", length, value));
2328 Assert(length > 0 && length <= 15, "invalid length");
2329 s->bits_sent += (ulg)length;
2330
2331 /* If not enough room in bi_buf, use (valid) bits from bi_buf and
2332 * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid))
2333 * unused bits in value.
2334 */
2335 if (s->bi_valid > (int)Buf_size - length) {
2336 s->bi_buf |= (value << s->bi_valid);
2337 put_short(s, s->bi_buf);
2338 s->bi_buf = (ush)value >> (Buf_size - s->bi_valid);
2339 s->bi_valid += length - Buf_size;
2340 } else {
2341 s->bi_buf |= value << s->bi_valid;
2342 s->bi_valid += length;
2343 }
2344 }
2345 #else /* !DEBUG_ZLIB */
2346
2347 #define send_bits(s, value, length) \
2348 { int len = length;\
2349 if (s->bi_valid > (int)Buf_size - len) {\
2350 int val = value;\
2351 s->bi_buf |= (val << s->bi_valid);\
2352 put_short(s, s->bi_buf);\
2353 s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\
2354 s->bi_valid += len - Buf_size;\
2355 } else {\
2356 s->bi_buf |= (value) << s->bi_valid;\
2357 s->bi_valid += len;\
2358 }\
2359 }
2360 #endif /* DEBUG_ZLIB */
2361
2362
2363 /* ===========================================================================
2364 * Initialize the various 'constant' tables.
2365 */
2366 local void tr_static_init()
2367 {
2368 #if defined(GEN_TREES_H) || !defined(STDC)
2369 static int static_init_done = 0;
2370 int n; /* iterates over tree elements */
2371 int bits; /* bit counter */
2372 int length; /* length value */
2373 int code; /* code value */
2374 int dist; /* distance index */
2375 ush bl_count[MAX_BITS+1];
2376 /* number of codes at each bit length for an optimal tree */
2377
2378 if (static_init_done) return;
2379
2380 /* For some embedded targets, global variables are not initialized: */
2381 static_l_desc.static_tree = static_ltree;
2382 static_l_desc.extra_bits = extra_lbits;
2383 static_d_desc.static_tree = static_dtree;
2384 static_d_desc.extra_bits = extra_dbits;
2385 static_bl_desc.extra_bits = extra_blbits;
2386
2387 /* Initialize the mapping length (0..255) -> length code (0..28) */
2388 length = 0;
2389 for (code = 0; code < LENGTH_CODES-1; code++) {
2390 base_length[code] = length;
2391 for (n = 0; n < (1<<extra_lbits[code]); n++) {
2392 _length_code[length++] = (uch)code;
2393 }
2394 }
2395 Assert (length == 256, "tr_static_init: length != 256");
2396 /* Note that the length 255 (match length 258) can be represented
2397 * in two different ways: code 284 + 5 bits or code 285, so we
2398 * overwrite length_code[255] to use the best encoding:
2399 */
2400 _length_code[length-1] = (uch)code;
2401
2402 /* Initialize the mapping dist (0..32K) -> dist code (0..29) */
2403 dist = 0;
2404 for (code = 0 ; code < 16; code++) {
2405 base_dist[code] = dist;
2406 for (n = 0; n < (1<<extra_dbits[code]); n++) {
2407 _dist_code[dist++] = (uch)code;
2408 }
2409 }
2410 Assert (dist == 256, "tr_static_init: dist != 256");
2411 dist >>= 7; /* from now on, all distances are divided by 128 */
2412 for ( ; code < D_CODES; code++) {
2413 base_dist[code] = dist << 7;
2414 for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) {
2415 _dist_code[256 + dist++] = (uch)code;
2416 }
2417 }
2418 Assert (dist == 256, "tr_static_init: 256+dist != 512");
2419
2420 /* Construct the codes of the static literal tree */
2421 for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
2422 n = 0;
2423 while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++;
2424 while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++;
2425 while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++;
2426 while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++;
2427 /* Codes 286 and 287 do not exist, but we must include them in the
2428 * tree construction to get a canonical Huffman tree (longest code
2429 * all ones)
2430 */
2431 gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count);
2432
2433 /* The static distance tree is trivial: */
2434 for (n = 0; n < D_CODES; n++) {
2435 static_dtree[n].Len = 5;
2436 static_dtree[n].Code = bi_reverse((unsigned)n, 5);
2437 }
2438 static_init_done = 1;
2439
2440 # ifdef GEN_TREES_H
2441 gen_trees_header();
2442 # endif
2443 #endif /* defined(GEN_TREES_H) || !defined(STDC) */
2444 }
2445
2446 /* ===========================================================================
2447 * Genererate the file trees.h describing the static trees.
2448 */
2449 #ifdef GEN_TREES_H
2450 # ifndef DEBUG_ZLIB
2451 # include <stdio.h>
2452 # endif
2453
2454 # define SEPARATOR(i, last, width) \
2455 ((i) == (last)? "\n};\n\n" : \
2456 ((i) % (width) == (width)-1 ? ",\n" : ", "))
2457
2458 void gen_trees_header()
2459 {
2460 FILE *header = fopen("trees.h", "w");
2461 int i;
2462
2463 Assert (header != NULL, "Can't open trees.h");
2464 fprintf(header,
2465 "/* header created automatically with -DGEN_TREES_H */\n\n");
2466
2467 fprintf(header, "local const ct_data static_ltree[L_CODES+2] = {\n");
2468 for (i = 0; i < L_CODES+2; i++) {
2469 fprintf(header, "{{%3u},{%3u}}%s", static_ltree[i].Code,
2470 static_ltree[i].Len, SEPARATOR(i, L_CODES+1, 5));
2471 }
2472
2473 fprintf(header, "local const ct_data static_dtree[D_CODES] = {\n");
2474 for (i = 0; i < D_CODES; i++) {
2475 fprintf(header, "{{%2u},{%2u}}%s", static_dtree[i].Code,
2476 static_dtree[i].Len, SEPARATOR(i, D_CODES-1, 5));
2477 }
2478
2479 fprintf(header, "const uch _dist_code[DIST_CODE_LEN] = {\n");
2480 for (i = 0; i < DIST_CODE_LEN; i++) {
2481 fprintf(header, "%2u%s", _dist_code[i],
2482 SEPARATOR(i, DIST_CODE_LEN-1, 20));
2483 }
2484
2485 fprintf(header, "const uch _length_code[MAX_MATCH-MIN_MATCH+1]= {\n");
2486 for (i = 0; i < MAX_MATCH-MIN_MATCH+1; i++) {
2487 fprintf(header, "%2u%s", _length_code[i],
2488 SEPARATOR(i, MAX_MATCH-MIN_MATCH, 20));
2489 }
2490
2491 fprintf(header, "local const int base_length[LENGTH_CODES] = {\n");
2492 for (i = 0; i < LENGTH_CODES; i++) {
2493 fprintf(header, "%1u%s", base_length[i],
2494 SEPARATOR(i, LENGTH_CODES-1, 20));
2495 }
2496
2497 fprintf(header, "local const int base_dist[D_CODES] = {\n");
2498 for (i = 0; i < D_CODES; i++) {
2499 fprintf(header, "%5u%s", base_dist[i],
2500 SEPARATOR(i, D_CODES-1, 10));
2501 }
2502
2503 fclose(header);
2504 }
2505 #endif /* GEN_TREES_H */
2506
2507 /* ===========================================================================
2508 * Initialize the tree data structures for a new zlib stream.
2509 */
2510 void _tr_init(s)
2511 deflate_state *s;
2512 {
2513 tr_static_init();
2514
2515 s->l_desc.dyn_tree = s->dyn_ltree;
2516 s->l_desc.stat_desc = &static_l_desc;
2517
2518 s->d_desc.dyn_tree = s->dyn_dtree;
2519 s->d_desc.stat_desc = &static_d_desc;
2520
2521 s->bl_desc.dyn_tree = s->bl_tree;
2522 s->bl_desc.stat_desc = &static_bl_desc;
2523
2524 s->bi_buf = 0;
2525 s->bi_valid = 0;
2526 s->last_eob_len = 8; /* enough lookahead for inflate */
2527 #ifdef DEBUG_ZLIB
2528 s->compressed_len = 0L;
2529 s->bits_sent = 0L;
2530 #endif
2531
2532 /* Initialize the first block of the first file: */
2533 init_block(s);
2534 }
2535
2536 /* ===========================================================================
2537 * Initialize a new block.
2538 */
2539 local void init_block(s)
2540 deflate_state *s;
2541 {
2542 int n; /* iterates over tree elements */
2543
2544 /* Initialize the trees. */
2545 for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0;
2546 for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0;
2547 for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0;
2548
2549 s->dyn_ltree[END_BLOCK].Freq = 1;
2550 s->opt_len = s->static_len = 0L;
2551 s->last_lit = s->matches = 0;
2552 }
2553
2554 #define SMALLEST 1
2555 /* Index within the heap array of least frequent node in the Huffman tree */
2556
2557
2558 /* ===========================================================================
2559 * Remove the smallest element from the heap and recreate the heap with
2560 * one less element. Updates heap and heap_len.
2561 */
2562 #define pqremove(s, tree, top) \
2563 {\
2564 top = s->heap[SMALLEST]; \
2565 s->heap[SMALLEST] = s->heap[s->heap_len--]; \
2566 pqdownheap(s, tree, SMALLEST); \
2567 }
2568
2569 /* ===========================================================================
2570 * Compares to subtrees, using the tree depth as tie breaker when
2571 * the subtrees have equal frequency. This minimizes the worst case length.
2572 */
2573 #define smaller(tree, n, m, depth) \
2574 (tree[n].Freq < tree[m].Freq || \
2575 (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m]))
2576
2577 /* ===========================================================================
2578 * Restore the heap property by moving down the tree starting at node k,
2579 * exchanging a node with the smallest of its two sons if necessary, stopping
2580 * when the heap property is re-established (each father smaller than its
2581 * two sons).
2582 */
2583 local void pqdownheap(s, tree, k)
2584 deflate_state *s;
2585 ct_data *tree; /* the tree to restore */
2586 int k; /* node to move down */
2587 {
2588 int v = s->heap[k];
2589 int j = k << 1; /* left son of k */
2590 while (j <= s->heap_len) {
2591 /* Set j to the smallest of the two sons: */
2592 if (j < s->heap_len &&
2593 smaller(tree, s->heap[j+1], s->heap[j], s->depth)) {
2594 j++;
2595 }
2596 /* Exit if v is smaller than both sons */
2597 if (smaller(tree, v, s->heap[j], s->depth)) break;
2598
2599 /* Exchange v with the smallest son */
2600 s->heap[k] = s->heap[j]; k = j;
2601
2602 /* And continue down the tree, setting j to the left son of k */
2603 j <<= 1;
2604 }
2605 s->heap[k] = v;
2606 }
2607
2608 /* ===========================================================================
2609 * Compute the optimal bit lengths for a tree and update the total bit length
2610 * for the current block.
2611 * IN assertion: the fields freq and dad are set, heap[heap_max] and
2612 * above are the tree nodes sorted by increasing frequency.
2613 * OUT assertions: the field len is set to the optimal bit length, the
2614 * array bl_count contains the frequencies for each bit length.
2615 * The length opt_len is updated; static_len is also updated if stree is
2616 * not null.
2617 */
2618 local void gen_bitlen(s, desc)
2619 deflate_state *s;
2620 tree_desc *desc; /* the tree descriptor */
2621 {
2622 ct_data *tree = desc->dyn_tree;
2623 int max_code = desc->max_code;
2624 const ct_data *stree = desc->stat_desc->static_tree;
2625 const intf *extra = desc->stat_desc->extra_bits;
2626 int base = desc->stat_desc->extra_base;
2627 int max_length = desc->stat_desc->max_length;
2628 int h; /* heap index */
2629 int n, m; /* iterate over the tree elements */
2630 int bits; /* bit length */
2631 int xbits; /* extra bits */
2632 ush f; /* frequency */
2633 int overflow = 0; /* number of elements with bit length too large */
2634
2635 for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0;
2636
2637 /* In a first pass, compute the optimal bit lengths (which may
2638 * overflow in the case of the bit length tree).
2639 */
2640 tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */
2641
2642 for (h = s->heap_max+1; h < HEAP_SIZE; h++) {
2643 n = s->heap[h];
2644 bits = tree[tree[n].Dad].Len + 1;
2645 if (bits > max_length) bits = max_length, overflow++;
2646 tree[n].Len = (ush)bits;
2647 /* We overwrite tree[n].Dad which is no longer needed */
2648
2649 if (n > max_code) continue; /* not a leaf node */
2650
2651 s->bl_count[bits]++;
2652 xbits = 0;
2653 if (n >= base) xbits = extra[n-base];
2654 f = tree[n].Freq;
2655 s->opt_len += (ulg)f * (bits + xbits);
2656 if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits);
2657 }
2658 if (overflow == 0) return;
2659
2660 Trace((stderr,"\nbit length overflow\n"));
2661 /* This happens for example on obj2 and pic of the Calgary corpus */
2662
2663 /* Find the first bit length which could increase: */
2664 do {
2665 bits = max_length-1;
2666 while (s->bl_count[bits] == 0) bits--;
2667 s->bl_count[bits]--; /* move one leaf down the tree */
2668 s->bl_count[bits+1] += 2; /* move one overflow item as its brother */
2669 s->bl_count[max_length]--;
2670 /* The brother of the overflow item also moves one step up,
2671 * but this does not affect bl_count[max_length]
2672 */
2673 overflow -= 2;
2674 } while (overflow > 0);
2675
2676 /* Now recompute all bit lengths, scanning in increasing frequency.
2677 * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
2678 * lengths instead of fixing only the wrong ones. This idea is taken
2679 * from 'ar' written by Haruhiko Okumura.)
2680 */
2681 for (bits = max_length; bits != 0; bits--) {
2682 n = s->bl_count[bits];
2683 while (n != 0) {
2684 m = s->heap[--h];
2685 if (m > max_code) continue;
2686 if (tree[m].Len != (unsigned) bits) {
2687 Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits));
2688 s->opt_len += ((long)bits - (long)tree[m].Len)
2689 *(long)tree[m].Freq;
2690 tree[m].Len = (ush)bits;
2691 }
2692 n--;
2693 }
2694 }
2695 }
2696
2697 /* ===========================================================================
2698 * Generate the codes for a given tree and bit counts (which need not be
2699 * optimal).
2700 * IN assertion: the array bl_count contains the bit length statistics for
2701 * the given tree and the field len is set for all tree elements.
2702 * OUT assertion: the field code is set for all tree elements of non
2703 * zero code length.
2704 */
2705 local void gen_codes (tree, max_code, bl_count)
2706 ct_data *tree; /* the tree to decorate */
2707 int max_code; /* largest code with non zero frequency */
2708 ushf *bl_count; /* number of codes at each bit length */
2709 {
2710 ush next_code[MAX_BITS+1]; /* next code value for each bit length */
2711 ush code = 0; /* running code value */
2712 int bits; /* bit index */
2713 int n; /* code index */
2714
2715 /* The distribution counts are first used to generate the code values
2716 * without bit reversal.
2717 */
2718 for (bits = 1; bits <= MAX_BITS; bits++) {
2719 next_code[bits] = code = (code + bl_count[bits-1]) << 1;
2720 }
2721 /* Check that the bit counts in bl_count are consistent. The last code
2722 * must be all ones.
2723 */
2724 Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1,
2725 "inconsistent bit counts");
2726 Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
2727
2728 for (n = 0; n <= max_code; n++) {
2729 int len = tree[n].Len;
2730 if (len == 0) continue;
2731 /* Now reverse the bits */
2732 tree[n].Code = bi_reverse(next_code[len]++, len);
2733
2734 Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
2735 n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1));
2736 }
2737 }
2738
2739 /* ===========================================================================
2740 * Construct one Huffman tree and assigns the code bit strings and lengths.
2741 * Update the total bit length for the current block.
2742 * IN assertion: the field freq is set for all tree elements.
2743 * OUT assertions: the fields len and code are set to the optimal bit length
2744 * and corresponding code. The length opt_len is updated; static_len is
2745 * also updated if stree is not null. The field max_code is set.
2746 */
2747 local void build_tree(s, desc)
2748 deflate_state *s;
2749 tree_desc *desc; /* the tree descriptor */
2750 {
2751 ct_data *tree = desc->dyn_tree;
2752 const ct_data *stree = desc->stat_desc->static_tree;
2753 int elems = desc->stat_desc->elems;
2754 int n, m; /* iterate over heap elements */
2755 int max_code = -1; /* largest code with non zero frequency */
2756 int node; /* new node being created */
2757
2758 /* Construct the initial heap, with least frequent element in
2759 * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
2760 * heap[0] is not used.
2761 */
2762 s->heap_len = 0, s->heap_max = HEAP_SIZE;
2763
2764 for (n = 0; n < elems; n++) {
2765 if (tree[n].Freq != 0) {
2766 s->heap[++(s->heap_len)] = max_code = n;
2767 s->depth[n] = 0;
2768 } else {
2769 tree[n].Len = 0;
2770 }
2771 }
2772
2773 /* The pkzip format requires that at least one distance code exists,
2774 * and that at least one bit should be sent even if there is only one
2775 * possible code. So to avoid special checks later on we force at least
2776 * two codes of non zero frequency.
2777 */
2778 while (s->heap_len < 2) {
2779 node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0);
2780 tree[node].Freq = 1;
2781 s->depth[node] = 0;
2782 s->opt_len--; if (stree) s->static_len -= stree[node].Len;
2783 /* node is 0 or 1 so it does not have extra bits */
2784 }
2785 desc->max_code = max_code;
2786
2787 /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
2788 * establish sub-heaps of increasing lengths:
2789 */
2790 for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n);
2791
2792 /* Construct the Huffman tree by repeatedly combining the least two
2793 * frequent nodes.
2794 */
2795 node = elems; /* next internal node of the tree */
2796 do {
2797 pqremove(s, tree, n); /* n = node of least frequency */
2798 m = s->heap[SMALLEST]; /* m = node of next least frequency */
2799
2800 s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */
2801 s->heap[--(s->heap_max)] = m;
2802
2803 /* Create a new node father of n and m */
2804 tree[node].Freq = tree[n].Freq + tree[m].Freq;
2805 s->depth[node] = (uch) (MAX(s->depth[n], s->depth[m]) + 1);
2806 tree[n].Dad = tree[m].Dad = (ush)node;
2807 #ifdef DUMP_BL_TREE
2808 if (tree == s->bl_tree) {
2809 fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)",
2810 node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq);
2811 }
2812 #endif
2813 /* and insert the new node in the heap */
2814 s->heap[SMALLEST] = node++;
2815 pqdownheap(s, tree, SMALLEST);
2816
2817 } while (s->heap_len >= 2);
2818
2819 s->heap[--(s->heap_max)] = s->heap[SMALLEST];
2820
2821 /* At this point, the fields freq and dad are set. We can now
2822 * generate the bit lengths.
2823 */
2824 gen_bitlen(s, (tree_desc *)desc);
2825
2826 /* The field len is now set, we can generate the bit codes */
2827 gen_codes ((ct_data *)tree, max_code, s->bl_count);
2828 }
2829
2830 /* ===========================================================================
2831 * Scan a literal or distance tree to determine the frequencies of the codes
2832 * in the bit length tree.
2833 */
2834 local void scan_tree (s, tree, max_code)
2835 deflate_state *s;
2836 ct_data *tree; /* the tree to be scanned */
2837 int max_code; /* and its largest code of non zero frequency */
2838 {
2839 int n; /* iterates over all tree elements */
2840 int prevlen = -1; /* last emitted length */
2841 int curlen; /* length of current code */
2842 int nextlen = tree[0].Len; /* length of next code */
2843 int count = 0; /* repeat count of the current code */
2844 int max_count = 7; /* max repeat count */
2845 int min_count = 4; /* min repeat count */
2846
2847 if (nextlen == 0) max_count = 138, min_count = 3;
2848 tree[max_code+1].Len = (ush)0xffff; /* guard */
2849
2850 for (n = 0; n <= max_code; n++) {
2851 curlen = nextlen; nextlen = tree[n+1].Len;
2852 if (++count < max_count && curlen == nextlen) {
2853 continue;
2854 } else if (count < min_count) {
2855 s->bl_tree[curlen].Freq += count;
2856 } else if (curlen != 0) {
2857 if (curlen != prevlen) s->bl_tree[curlen].Freq++;
2858 s->bl_tree[REP_3_6].Freq++;
2859 } else if (count <= 10) {
2860 s->bl_tree[REPZ_3_10].Freq++;
2861 } else {
2862 s->bl_tree[REPZ_11_138].Freq++;
2863 }
2864 count = 0; prevlen = curlen;
2865 if (nextlen == 0) {
2866 max_count = 138, min_count = 3;
2867 } else if (curlen == nextlen) {
2868 max_count = 6, min_count = 3;
2869 } else {
2870 max_count = 7, min_count = 4;
2871 }
2872 }
2873 }
2874
2875 /* ===========================================================================
2876 * Send a literal or distance tree in compressed form, using the codes in
2877 * bl_tree.
2878 */
2879 local void send_tree (s, tree, max_code)
2880 deflate_state *s;
2881 ct_data *tree; /* the tree to be scanned */
2882 int max_code; /* and its largest code of non zero frequency */
2883 {
2884 int n; /* iterates over all tree elements */
2885 int prevlen = -1; /* last emitted length */
2886 int curlen; /* length of current code */
2887 int nextlen = tree[0].Len; /* length of next code */
2888 int count = 0; /* repeat count of the current code */
2889 int max_count = 7; /* max repeat count */
2890 int min_count = 4; /* min repeat count */
2891
2892 /* tree[max_code+1].Len = -1; */ /* guard already set */
2893 if (nextlen == 0) max_count = 138, min_count = 3;
2894
2895 for (n = 0; n <= max_code; n++) {
2896 curlen = nextlen; nextlen = tree[n+1].Len;
2897 if (++count < max_count && curlen == nextlen) {
2898 continue;
2899 } else if (count < min_count) {
2900 do { send_code(s, curlen, s->bl_tree); } while (--count != 0);
2901
2902 } else if (curlen != 0) {
2903 if (curlen != prevlen) {
2904 send_code(s, curlen, s->bl_tree); count--;
2905 }
2906 Assert(count >= 3 && count <= 6, " 3_6?");
2907 send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2);
2908
2909 } else if (count <= 10) {
2910 send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3);
2911
2912 } else {
2913 send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7);
2914 }
2915 count = 0; prevlen = curlen;
2916 if (nextlen == 0) {
2917 max_count = 138, min_count = 3;
2918 } else if (curlen == nextlen) {
2919 max_count = 6, min_count = 3;
2920 } else {
2921 max_count = 7, min_count = 4;
2922 }
2923 }
2924 }
2925
2926 /* ===========================================================================
2927 * Construct the Huffman tree for the bit lengths and return the index in
2928 * bl_order of the last bit length code to send.
2929 */
2930 local int build_bl_tree(s)
2931 deflate_state *s;
2932 {
2933 int max_blindex; /* index of last bit length code of non zero freq */
2934
2935 /* Determine the bit length frequencies for literal and distance trees */
2936 scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code);
2937 scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code);
2938
2939 /* Build the bit length tree: */
2940 build_tree(s, (tree_desc *)(&(s->bl_desc)));
2941 /* opt_len now includes the length of the tree representations, except
2942 * the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
2943 */
2944
2945 /* Determine the number of bit length codes to send. The pkzip format
2946 * requires that at least 4 bit length codes be sent. (appnote.txt says
2947 * 3 but the actual value used is 4.)
2948 */
2949 for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) {
2950 if (s->bl_tree[bl_order[max_blindex]].Len != 0) break;
2951 }
2952 /* Update opt_len to include the bit length tree and counts */
2953 s->opt_len += 3*(max_blindex+1) + 5+5+4;
2954 Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld",
2955 s->opt_len, s->static_len));
2956
2957 return max_blindex;
2958 }
2959
2960 /* ===========================================================================
2961 * Send the header for a block using dynamic Huffman trees: the counts, the
2962 * lengths of the bit length codes, the literal tree and the distance tree.
2963 * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
2964 */
2965 local void send_all_trees(s, lcodes, dcodes, blcodes)
2966 deflate_state *s;
2967 int lcodes, dcodes, blcodes; /* number of codes for each tree */
2968 {
2969 int rank; /* index in bl_order */
2970
2971 Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
2972 Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
2973 "too many codes");
2974 Tracev((stderr, "\nbl counts: "));
2975 send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */
2976 send_bits(s, dcodes-1, 5);
2977 send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */
2978 for (rank = 0; rank < blcodes; rank++) {
2979 Tracev((stderr, "\nbl code %2d ", bl_order[rank]));
2980 send_bits(s, s->bl_tree[bl_order[rank]].Len, 3);
2981 }
2982 Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent));
2983
2984 send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */
2985 Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent));
2986
2987 send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */
2988 Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent));
2989 }
2990
2991 /* ===========================================================================
2992 * Send a stored block
2993 */
2994 void _tr_stored_block(s, buf, stored_len, eof)
2995 deflate_state *s;
2996 charf *buf; /* input block */
2997 ulg stored_len; /* length of input block */
2998 int eof; /* true if this is the last block for a file */
2999 {
3000 send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */
3001 #ifdef DEBUG_ZLIB
3002 s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L;
3003 s->compressed_len += (stored_len + 4) << 3;
3004 #endif
3005 copy_block(s, buf, (unsigned)stored_len, 1); /* with header */
3006 }
3007
3008 /* Send just the `stored block' type code without any length bytes or data.
3009 */
3010 void _tr_stored_type_only(s)
3011 deflate_state *s;
3012 {
3013 send_bits(s, (STORED_BLOCK << 1), 3);
3014 bi_windup(s);
3015 #ifdef DEBUG_ZLIB
3016 s->compressed_len = (s->compressed_len + 3) & ~7L;
3017 #endif
3018 }
3019
3020 /* ===========================================================================
3021 * Send one empty static block to give enough lookahead for inflate.
3022 * This takes 10 bits, of which 7 may remain in the bit buffer.
3023 * The current inflate code requires 9 bits of lookahead. If the
3024 * last two codes for the previous block (real code plus EOB) were coded
3025 * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode
3026 * the last real code. In this case we send two empty static blocks instead
3027 * of one. (There are no problems if the previous block is stored or fixed.)
3028 * To simplify the code, we assume the worst case of last real code encoded
3029 * on one bit only.
3030 */
3031 void _tr_align(s)
3032 deflate_state *s;
3033 {
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; /* 3 for block type, 7 for EOB */
3038 #endif
3039 bi_flush(s);
3040 /* Of the 10 bits for the empty block, we have already sent
3041 * (10 - bi_valid) bits. The lookahead for the last real code (before
3042 * the EOB of the previous block) was thus at least one plus the length
3043 * of the EOB plus what we have just sent of the empty static block.
3044 */
3045 if (1 + s->last_eob_len + 10 - s->bi_valid < 9) {
3046 send_bits(s, STATIC_TREES<<1, 3);
3047 send_code(s, END_BLOCK, static_ltree);
3048 #ifdef DEBUG_ZLIB
3049 s->compressed_len += 10L;
3050 #endif
3051 bi_flush(s);
3052 }
3053 s->last_eob_len = 7;
3054 }
3055
3056 /* ===========================================================================
3057 * Determine the best encoding for the current block: dynamic trees, static
3058 * trees or store, and output the encoded block to the zip file.
3059 */
3060 void _tr_flush_block(s, buf, stored_len, eof)
3061 deflate_state *s;
3062 charf *buf; /* input block, or NULL if too old */
3063 ulg stored_len; /* length of input block */
3064 int eof; /* true if this is the last block for a file */
3065 {
3066 ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
3067 int max_blindex = 0; /* index of last bit length code of non zero freq */
3068
3069 /* Build the Huffman trees unless a stored block is forced */
3070 if (s->level > 0) {
3071
3072 /* Check if the file is ascii or binary */
3073 if (s->data_type == Z_UNKNOWN) set_data_type(s);
3074
3075 /* Construct the literal and distance trees */
3076 build_tree(s, (tree_desc *)(&(s->l_desc)));
3077 Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len,
3078 s->static_len));
3079
3080 build_tree(s, (tree_desc *)(&(s->d_desc)));
3081 Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len,
3082 s->static_len));
3083 /* At this point, opt_len and static_len are the total bit lengths of
3084 * the compressed block data, excluding the tree representations.
3085 */
3086
3087 /* Build the bit length tree for the above two trees, and get the index
3088 * in bl_order of the last bit length code to send.
3089 */
3090 max_blindex = build_bl_tree(s);
3091
3092 /* Determine the best encoding. Compute first the block length in bytes*/
3093 opt_lenb = (s->opt_len+3+7)>>3;
3094 static_lenb = (s->static_len+3+7)>>3;
3095
3096 Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
3097 opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
3098 s->last_lit));
3099
3100 if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
3101
3102 } else {
3103 Assert(buf != (char*)0, "lost buf");
3104 opt_lenb = static_lenb = stored_len + 5; /* force a stored block */
3105 }
3106
3107 #ifdef FORCE_STORED
3108 if (buf != (char*)0) { /* force stored block */
3109 #else
3110 if (stored_len+4 <= opt_lenb && buf != (char*)0) {
3111 /* 4: two words for the lengths */
3112 #endif
3113 /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
3114 * Otherwise we can't have processed more than WSIZE input bytes since
3115 * the last block flush, because compression would have been
3116 * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
3117 * transform a block into a stored block.
3118 */
3119 _tr_stored_block(s, buf, stored_len, eof);
3120
3121 #ifdef FORCE_STATIC
3122 } else if (static_lenb >= 0) { /* force static trees */
3123 #else
3124 } else if (static_lenb == opt_lenb) {
3125 #endif
3126 send_bits(s, (STATIC_TREES<<1)+eof, 3);
3127 compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree);
3128 #ifdef DEBUG_ZLIB
3129 s->compressed_len += 3 + s->static_len;
3130 #endif
3131 } else {
3132 send_bits(s, (DYN_TREES<<1)+eof, 3);
3133 send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1,
3134 max_blindex+1);
3135 compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree);
3136 #ifdef DEBUG_ZLIB
3137 s->compressed_len += 3 + s->opt_len;
3138 #endif
3139 }
3140 Assert (s->compressed_len == s->bits_sent, "bad compressed size");
3141 /* The above check is made mod 2^32, for files larger than 512 MB
3142 * and uLong implemented on 32 bits.
3143 */
3144 init_block(s);
3145
3146 if (eof) {
3147 bi_windup(s);
3148 #ifdef DEBUG_ZLIB
3149 s->compressed_len += 7; /* align on byte boundary */
3150 #endif
3151 }
3152 Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3,
3153 s->compressed_len-7*eof));
3154 }
3155
3156 /* ===========================================================================
3157 * Save the match info and tally the frequency counts. Return true if
3158 * the current block must be flushed.
3159 */
3160 #if 0
3161 int _tr_tally (s, dist, lc)
3162 deflate_state *s;
3163 unsigned dist; /* distance of matched string */
3164 unsigned lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */
3165 {
3166 s->d_buf[s->last_lit] = (ush)dist;
3167 s->l_buf[s->last_lit++] = (uch)lc;
3168 if (dist == 0) {
3169 /* lc is the unmatched char */
3170 s->dyn_ltree[lc].Freq++;
3171 } else {
3172 s->matches++;
3173 /* Here, lc is the match length - MIN_MATCH */
3174 dist--; /* dist = match distance - 1 */
3175 Assert((ush)dist < (ush)MAX_DIST(s) &&
3176 (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
3177 (ush)d_code(dist) < (ush)D_CODES, "_tr_tally: bad match");
3178
3179 s->dyn_ltree[_length_code[lc]+LITERALS+1].Freq++;
3180 s->dyn_dtree[d_code(dist)].Freq++;
3181 }
3182
3183 #ifdef TRUNCATE_BLOCK
3184 /* Try to guess if it is profitable to stop the current block here */
3185 if ((s->last_lit & 0x1fff) == 0 && s->level > 2) {
3186 /* Compute an upper bound for the compressed length */
3187 ulg out_length = (ulg)s->last_lit*8L;
3188 ulg in_length = (ulg)((long)s->strstart - s->block_start);
3189 int dcode;
3190 for (dcode = 0; dcode < D_CODES; dcode++) {
3191 out_length += (ulg)s->dyn_dtree[dcode].Freq *
3192 (5L+extra_dbits[dcode]);
3193 }
3194 out_length >>= 3;
3195 Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ",
3196 s->last_lit, in_length, out_length,
3197 100L - out_length*100L/in_length));
3198 if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1;
3199 }
3200 #endif
3201 return (s->last_lit == s->lit_bufsize-1);
3202 /* We avoid equality with lit_bufsize because of wraparound at 64K
3203 * on 16 bit machines and because stored blocks are restricted to
3204 * 64K-1 bytes.
3205 */
3206 }
3207 #endif
3208
3209 /* ===========================================================================
3210 * Send the block data compressed using the given Huffman trees
3211 */
3212 local void compress_block(s, ltree, dtree)
3213 deflate_state *s;
3214 ct_data *ltree; /* literal tree */
3215 ct_data *dtree; /* distance tree */
3216 {
3217 unsigned dist; /* distance of matched string */
3218 int lc; /* match length or unmatched char (if dist == 0) */
3219 unsigned lx = 0; /* running index in l_buf */
3220 unsigned code; /* the code to send */
3221 int extra; /* number of extra bits to send */
3222
3223 if (s->last_lit != 0) do {
3224 dist = s->d_buf[lx];
3225 lc = s->l_buf[lx++];
3226 if (dist == 0) {
3227 send_code(s, lc, ltree); /* send a literal byte */
3228 Tracecv(isgraph(lc), (stderr," '%c' ", lc));
3229 } else {
3230 /* Here, lc is the match length - MIN_MATCH */
3231 code = _length_code[lc];
3232 send_code(s, code+LITERALS+1, ltree); /* send the length code */
3233 extra = extra_lbits[code];
3234 if (extra != 0) {
3235 lc -= base_length[code];
3236 send_bits(s, lc, extra); /* send the extra length bits */
3237 }
3238 dist--; /* dist is now the match distance - 1 */
3239 code = d_code(dist);
3240 Assert (code < D_CODES, "bad d_code");
3241
3242 send_code(s, code, dtree); /* send the distance code */
3243 extra = extra_dbits[code];
3244 if (extra != 0) {
3245 dist -= base_dist[code];
3246 send_bits(s, dist, extra); /* send the extra distance bits */
3247 }
3248 } /* literal or match pair ? */
3249
3250 /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */
3251 Assert(s->pending < s->lit_bufsize + 2*lx, "pendingBuf overflow");
3252
3253 } while (lx < s->last_lit);
3254
3255 send_code(s, END_BLOCK, ltree);
3256 s->last_eob_len = ltree[END_BLOCK].Len;
3257 }
3258
3259 /* ===========================================================================
3260 * Set the data type to ASCII or BINARY, using a crude approximation:
3261 * binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise.
3262 * IN assertion: the fields freq of dyn_ltree are set and the total of all
3263 * frequencies does not exceed 64K (to fit in an int on 16 bit machines).
3264 */
3265 local void set_data_type(s)
3266 deflate_state *s;
3267 {
3268 int n = 0;
3269 unsigned ascii_freq = 0;
3270 unsigned bin_freq = 0;
3271 while (n < 7) bin_freq += s->dyn_ltree[n++].Freq;
3272 while (n < 128) ascii_freq += s->dyn_ltree[n++].Freq;
3273 while (n < LITERALS) bin_freq += s->dyn_ltree[n++].Freq;
3274 s->data_type = (Byte)(bin_freq > (ascii_freq >> 2) ? Z_BINARY : Z_ASCII);
3275 }
3276
3277 /* ===========================================================================
3278 * Reverse the first len bits of a code, using straightforward code (a faster
3279 * method would use a table)
3280 * IN assertion: 1 <= len <= 15
3281 */
3282 local unsigned bi_reverse(code, len)
3283 unsigned code; /* the value to invert */
3284 int len; /* its bit length */
3285 {
3286 unsigned res = 0;
3287 do {
3288 res |= code & 1;
3289 code >>= 1, res <<= 1;
3290 } while (--len > 0);
3291 return res >> 1;
3292 }
3293
3294 /* ===========================================================================
3295 * Flush the bit buffer, keeping at most 7 bits in it.
3296 */
3297 local void bi_flush(s)
3298 deflate_state *s;
3299 {
3300 if (s->bi_valid == 16) {
3301 put_short(s, s->bi_buf);
3302 s->bi_buf = 0;
3303 s->bi_valid = 0;
3304 } else if (s->bi_valid >= 8) {
3305 put_byte(s, (Byte)s->bi_buf);
3306 s->bi_buf >>= 8;
3307 s->bi_valid -= 8;
3308 }
3309 }
3310
3311 /* ===========================================================================
3312 * Flush the bit buffer and align the output on a byte boundary
3313 */
3314 local void bi_windup(s)
3315 deflate_state *s;
3316 {
3317 if (s->bi_valid > 8) {
3318 put_short(s, s->bi_buf);
3319 } else if (s->bi_valid > 0) {
3320 put_byte(s, (Byte)s->bi_buf);
3321 }
3322 s->bi_buf = 0;
3323 s->bi_valid = 0;
3324 #ifdef DEBUG_ZLIB
3325 s->bits_sent = (s->bits_sent+7) & ~7;
3326 #endif
3327 }
3328
3329 /* ===========================================================================
3330 * Copy a stored block, storing first the length and its
3331 * one's complement if requested.
3332 */
3333 local void copy_block(s, buf, len, header)
3334 deflate_state *s;
3335 charf *buf; /* the input data */
3336 unsigned len; /* its length */
3337 int header; /* true if block header must be written */
3338 {
3339 bi_windup(s); /* align on byte boundary */
3340 s->last_eob_len = 8; /* enough lookahead for inflate */
3341
3342 if (header) {
3343 put_short(s, (ush)len);
3344 put_short(s, (ush)~len);
3345 #ifdef DEBUG_ZLIB
3346 s->bits_sent += 2*16;
3347 #endif
3348 }
3349 #ifdef DEBUG_ZLIB
3350 s->bits_sent += (ulg)len<<3;
3351 #endif
3352 /* bundle up the put_byte(s, *buf++) calls */
3353 zmemcpy(&s->pending_buf[s->pending], buf, len);
3354 s->pending += len;
3355 }
3356 /* --- trees.c */
3357
3358 /* +++ inflate.c */
3359
3360 /* inflate.c -- zlib interface to inflate modules
3361 * Copyright (C) 1995-2002 Mark Adler
3362 * For conditions of distribution and use, see copyright notice in zlib.h
3363 */
3364
3365 /* #include "zutil.h" */
3366
3367 /* +++ infblock.h */
3368
3369 /* infblock.h -- header to use infblock.c
3370 * Copyright (C) 1995-2002 Mark Adler
3371 * For conditions of distribution and use, see copyright notice in zlib.h
3372 */
3373
3374 /* WARNING: this file should *not* be used by applications. It is
3375 part of the implementation of the compression library and is
3376 subject to change. Applications should only use zlib.h.
3377 */
3378
3379 struct inflate_blocks_state;
3380 typedef struct inflate_blocks_state FAR inflate_blocks_statef;
3381
3382 extern inflate_blocks_statef * inflate_blocks_new __P((
3383 z_streamp z,
3384 check_func c, /* check function */
3385 uInt w)); /* window size */
3386
3387 extern int inflate_blocks __P((
3388 inflate_blocks_statef *,
3389 z_streamp ,
3390 int)); /* initial return code */
3391
3392 extern void inflate_blocks_reset __P((
3393 inflate_blocks_statef *,
3394 z_streamp ,
3395 uLongf *)); /* check value on output */
3396
3397 extern int inflate_blocks_free __P((
3398 inflate_blocks_statef *,
3399 z_streamp));
3400
3401 extern void inflate_set_dictionary __P((
3402 inflate_blocks_statef *s,
3403 const Bytef *d, /* dictionary */
3404 uInt n)); /* dictionary length */
3405
3406 extern int inflate_blocks_sync_point __P((
3407 inflate_blocks_statef *s));
3408 extern int inflate_addhistory __P((
3409 inflate_blocks_statef *,
3410 z_streamp));
3411
3412 extern int inflate_packet_flush __P((
3413 inflate_blocks_statef *));
3414
3415 /* --- infblock.h */
3416
3417 #ifndef NO_DUMMY_DECL
3418 struct inflate_blocks_state {int dummy;}; /* for buggy compilers */
3419 #endif
3420
3421 typedef enum {
3422 METHOD, /* waiting for method byte */
3423 FLAG, /* waiting for flag byte */
3424 DICT4, /* four dictionary check bytes to go */
3425 DICT3, /* three dictionary check bytes to go */
3426 DICT2, /* two dictionary check bytes to go */
3427 DICT1, /* one dictionary check byte to go */
3428 DICT0, /* waiting for inflateSetDictionary */
3429 BLOCKS, /* decompressing blocks */
3430 CHECK4, /* four check bytes to go */
3431 CHECK3, /* three check bytes to go */
3432 CHECK2, /* two check bytes to go */
3433 CHECK1, /* one check byte to go */
3434 DONE, /* finished check, done */
3435 BAD} /* got an error--stay here */
3436 inflate_mode;
3437
3438 /* inflate private state */
3439 struct internal_state {
3440
3441 /* mode */
3442 inflate_mode mode; /* current inflate mode */
3443
3444 /* mode dependent information */
3445 union {
3446 uInt method; /* if FLAGS, method byte */
3447 struct {
3448 uLong was; /* computed check value */
3449 uLong need; /* stream check value */
3450 } check; /* if CHECK, check values to compare */
3451 uInt marker; /* if BAD, inflateSync's marker bytes count */
3452 } sub; /* submode */
3453
3454 /* mode independent information */
3455 int nowrap; /* flag for no wrapper */
3456 uInt wbits; /* log2(window size) (8..15, defaults to 15) */
3457 inflate_blocks_statef
3458 *blocks; /* current inflate_blocks state */
3459
3460 };
3461
3462
3463 int ZEXPORT inflateReset(z)
3464 z_streamp z;
3465 {
3466 if (z == Z_NULL || z->state == Z_NULL)
3467 return Z_STREAM_ERROR;
3468 z->total_in = z->total_out = 0;
3469 z->msg = Z_NULL;
3470 z->state->mode = z->state->nowrap ? BLOCKS : METHOD;
3471 inflate_blocks_reset(z->state->blocks, z, Z_NULL);
3472 Tracev((stderr, "inflate: reset\n"));
3473 return Z_OK;
3474 }
3475
3476
3477 int ZEXPORT inflateEnd(z)
3478 z_streamp z;
3479 {
3480 if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL)
3481 return Z_STREAM_ERROR;
3482 if (z->state->blocks != Z_NULL)
3483 inflate_blocks_free(z->state->blocks, z);
3484 ZFREE(z, z->state);
3485 z->state = Z_NULL;
3486 Tracev((stderr, "inflate: end\n"));
3487 return Z_OK;
3488 }
3489
3490
3491 int ZEXPORT inflateInit2_(z, w, version, stream_size)
3492 z_streamp z;
3493 int w;
3494 const char *version;
3495 int stream_size;
3496 {
3497 if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
3498 stream_size != sizeof(z_stream))
3499 return Z_VERSION_ERROR;
3500
3501 /* initialize state */
3502 if (z == Z_NULL)
3503 return Z_STREAM_ERROR;
3504 z->msg = Z_NULL;
3505 #ifndef NO_ZCFUNCS
3506 if (z->zalloc == Z_NULL)
3507 {
3508 z->zalloc = zcalloc;
3509 z->opaque = (voidpf)0;
3510 }
3511 if (z->zfree == Z_NULL) z->zfree = zcfree;
3512 #endif
3513 if ((z->state = (struct internal_state FAR *)
3514 ZALLOC(z,1,sizeof(struct internal_state))) == Z_NULL)
3515 return Z_MEM_ERROR;
3516 z->state->blocks = Z_NULL;
3517
3518 /* handle undocumented nowrap option (no zlib header or check) */
3519 z->state->nowrap = 0;
3520 if (w < 0)
3521 {
3522 w = - w;
3523 z->state->nowrap = 1;
3524 }
3525
3526 /* set window size */
3527 if (w < 8 || w > 15)
3528 {
3529 inflateEnd(z);
3530 return Z_STREAM_ERROR;
3531 }
3532 z->state->wbits = (uInt)w;
3533
3534 /* create inflate_blocks state */
3535 if ((z->state->blocks =
3536 inflate_blocks_new(z, z->state->nowrap ? Z_NULL : adler32, (uInt)1 << w))
3537 == Z_NULL)
3538 {
3539 inflateEnd(z);
3540 return Z_MEM_ERROR;
3541 }
3542 Tracev((stderr, "inflate: allocated\n"));
3543
3544 /* reset state */
3545 inflateReset(z);
3546 return Z_OK;
3547 }
3548
3549
3550 #if 0
3551 int ZEXPORT inflateInit_(z, version, stream_size)
3552 z_streamp z;
3553 const char *version;
3554 int stream_size;
3555 {
3556 return inflateInit2_(z, DEF_WBITS, version, stream_size);
3557 }
3558 #endif
3559
3560
3561 #define NEEDBYTE {if(z->avail_in==0)goto empty;r=Z_OK;}
3562 #define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++)
3563
3564 int ZEXPORT inflate(z, f)
3565 z_streamp z;
3566 int f;
3567 {
3568 int r, r2;
3569 uInt b;
3570
3571 if (z == Z_NULL || z->state == Z_NULL || z->next_in == Z_NULL)
3572 return Z_STREAM_ERROR;
3573 r2 = f == Z_FINISH ? Z_BUF_ERROR : Z_OK;
3574 r = Z_BUF_ERROR;
3575 while (1) switch (z->state->mode)
3576 {
3577 case METHOD:
3578 NEEDBYTE
3579 if (((z->state->sub.method = NEXTBYTE) & 0xf) != Z_DEFLATED)
3580 {
3581 z->state->mode = BAD;
3582 z->msg = (char*)"unknown compression method";
3583 z->state->sub.marker = 5; /* can't try inflateSync */
3584 break;
3585 }
3586 if ((z->state->sub.method >> 4) + 8 > z->state->wbits)
3587 {
3588 z->state->mode = BAD;
3589 z->msg = (char*)"invalid window size";
3590 z->state->sub.marker = 5; /* can't try inflateSync */
3591 break;
3592 }
3593 z->state->mode = FLAG;
3594 case FLAG:
3595 NEEDBYTE
3596 b = NEXTBYTE;
3597 if (((z->state->sub.method << 8) + b) % 31)
3598 {
3599 z->state->mode = BAD;
3600 z->msg = (char*)"incorrect header check";
3601 z->state->sub.marker = 5; /* can't try inflateSync */
3602 break;
3603 }
3604 Tracev((stderr, "inflate: zlib header ok\n"));
3605 if (!(b & PRESET_DICT))
3606 {
3607 z->state->mode = BLOCKS;
3608 break;
3609 }
3610 z->state->mode = DICT4;
3611 case DICT4:
3612 NEEDBYTE
3613 z->state->sub.check.need = (uLong)NEXTBYTE << 24;
3614 z->state->mode = DICT3;
3615 case DICT3:
3616 NEEDBYTE
3617 z->state->sub.check.need += (uLong)NEXTBYTE << 16;
3618 z->state->mode = DICT2;
3619 case DICT2:
3620 NEEDBYTE
3621 z->state->sub.check.need += (uLong)NEXTBYTE << 8;
3622 z->state->mode = DICT1;
3623 case DICT1:
3624 NEEDBYTE
3625 z->state->sub.check.need += (uLong)NEXTBYTE;
3626 z->adler = z->state->sub.check.need;
3627 z->state->mode = DICT0;
3628 return Z_NEED_DICT;
3629 case DICT0:
3630 z->state->mode = BAD;
3631 z->msg = (char*)"need dictionary";
3632 z->state->sub.marker = 0; /* can try inflateSync */
3633 return Z_STREAM_ERROR;
3634 case BLOCKS:
3635 r = inflate_blocks(z->state->blocks, z, r);
3636 if (f == Z_PACKET_FLUSH && z->avail_in == 0 && z->avail_out != 0)
3637 r = inflate_packet_flush(z->state->blocks);
3638 if (r == Z_DATA_ERROR)
3639 {
3640 z->state->mode = BAD;
3641 z->state->sub.marker = 0; /* can try inflateSync */
3642 break;
3643 }
3644 if (r == Z_OK)
3645 r = r2;
3646 if (r != Z_STREAM_END)
3647 return r;
3648 r = r2;
3649 inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was);
3650 if (z->state->nowrap)
3651 {
3652 z->state->mode = DONE;
3653 break;
3654 }
3655 z->state->mode = CHECK4;
3656 case CHECK4:
3657 NEEDBYTE
3658 z->state->sub.check.need = (uLong)NEXTBYTE << 24;
3659 z->state->mode = CHECK3;
3660 case CHECK3:
3661 NEEDBYTE
3662 z->state->sub.check.need += (uLong)NEXTBYTE << 16;
3663 z->state->mode = CHECK2;
3664 case CHECK2:
3665 NEEDBYTE
3666 z->state->sub.check.need += (uLong)NEXTBYTE << 8;
3667 z->state->mode = CHECK1;
3668 case CHECK1:
3669 NEEDBYTE
3670 z->state->sub.check.need += (uLong)NEXTBYTE;
3671
3672 if (z->state->sub.check.was != z->state->sub.check.need)
3673 {
3674 z->state->mode = BAD;
3675 z->msg = (char*)"incorrect data check";
3676 z->state->sub.marker = 5; /* can't try inflateSync */
3677 break;
3678 }
3679 Tracev((stderr, "inflate: zlib check ok\n"));
3680 z->state->mode = DONE;
3681 case DONE:
3682 return Z_STREAM_END;
3683 case BAD:
3684 return Z_DATA_ERROR;
3685 default:
3686 return Z_STREAM_ERROR;
3687 }
3688 empty:
3689 if (f != Z_PACKET_FLUSH)
3690 return r;
3691 z->state->mode = BAD;
3692 z->msg = (char *)"need more for packet flush";
3693 z->state->sub.marker = 0;
3694 return Z_DATA_ERROR;
3695 }
3696
3697
3698 #if 0
3699 int ZEXPORT inflateSetDictionary(z, dictionary, dictLength)
3700 z_streamp z;
3701 const Bytef *dictionary;
3702 uInt dictLength;
3703 {
3704 uInt length = dictLength;
3705
3706 if (z == Z_NULL || z->state == Z_NULL || z->state->mode != DICT0)
3707 return Z_STREAM_ERROR;
3708
3709 if (adler32(1L, dictionary, dictLength) != z->adler) return Z_DATA_ERROR;
3710 z->adler = 1L;
3711
3712 if (length >= ((uInt)1<<z->state->wbits))
3713 {
3714 length = (1<<z->state->wbits)-1;
3715 dictionary += dictLength - length;
3716 }
3717 inflate_set_dictionary(z->state->blocks, dictionary, length);
3718 z->state->mode = BLOCKS;
3719 return Z_OK;
3720 }
3721 #endif
3722
3723 /*
3724 * This subroutine adds the data at next_in/avail_in to the output history
3725 * without performing any output. The output buffer must be "caught up";
3726 * i.e. no pending output (hence s->read equals s->write), and the state must
3727 * be BLOCKS (i.e. we should be willing to see the start of a series of
3728 * BLOCKS). On exit, the output will also be caught up, and the checksum
3729 * will have been updated if need be.
3730 */
3731
3732 int inflateIncomp(z)
3733 z_stream *z;
3734 {
3735 if (z->state->mode != BLOCKS)
3736 return Z_DATA_ERROR;
3737 return inflate_addhistory(z->state->blocks, z);
3738 }
3739
3740 #if 0
3741 int ZEXPORT inflateSync(z)
3742 z_streamp z;
3743 {
3744 uInt n; /* number of bytes to look at */
3745 Bytef *p; /* pointer to bytes */
3746 uInt m; /* number of marker bytes found in a row */
3747 uLong r, w; /* temporaries to save total_in and total_out */
3748
3749 /* set up */
3750 if (z == Z_NULL || z->state == Z_NULL)
3751 return Z_STREAM_ERROR;
3752 if (z->state->mode != BAD)
3753 {
3754 z->state->mode = BAD;
3755 z->state->sub.marker = 0;
3756 }
3757 if ((n = z->avail_in) == 0)
3758 return Z_BUF_ERROR;
3759 p = z->next_in;
3760 m = z->state->sub.marker;
3761
3762 /* search */
3763 while (n && m < 4)
3764 {
3765 static const Byte mark[4] = {0, 0, 0xff, 0xff};
3766 if (*p == mark[m])
3767 m++;
3768 else if (*p)
3769 m = 0;
3770 else
3771 m = 4 - m;
3772 p++, n--;
3773 }
3774
3775 /* restore */
3776 z->total_in += p - z->next_in;
3777 z->next_in = p;
3778 z->avail_in = n;
3779 z->state->sub.marker = m;
3780
3781 /* return no joy or set up to restart on a new block */
3782 if (m != 4)
3783 return Z_DATA_ERROR;
3784 r = z->total_in; w = z->total_out;
3785 inflateReset(z);
3786 z->total_in = r; z->total_out = w;
3787 z->state->mode = BLOCKS;
3788 return Z_OK;
3789 }
3790 #endif
3791
3792
3793 /* Returns true if inflate is currently at the end of a block generated
3794 * by Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
3795 * implementation to provide an additional safety check. PPP uses Z_SYNC_FLUSH
3796 * but removes the length bytes of the resulting empty stored block. When
3797 * decompressing, PPP checks that at the end of input packet, inflate is
3798 * waiting for these length bytes.
3799 */
3800 #if 0
3801 int ZEXPORT inflateSyncPoint(z)
3802 z_streamp z;
3803 {
3804 if (z == Z_NULL || z->state == Z_NULL || z->state->blocks == Z_NULL)
3805 return Z_STREAM_ERROR;
3806 return inflate_blocks_sync_point(z->state->blocks);
3807 }
3808 #endif
3809 #undef NEEDBYTE
3810 #undef NEXTBYTE
3811 /* --- inflate.c */
3812
3813 /* +++ infblock.c */
3814
3815 /* infblock.c -- interpret and process block types to last block
3816 * Copyright (C) 1995-2002 Mark Adler
3817 * For conditions of distribution and use, see copyright notice in zlib.h
3818 */
3819
3820 /* #include "zutil.h" */
3821 /* #include "infblock.h" */
3822
3823 /* +++ inftrees.h */
3824
3825 /* inftrees.h -- header to use inftrees.c
3826 * Copyright (C) 1995-2002 Mark Adler
3827 * For conditions of distribution and use, see copyright notice in zlib.h
3828 */
3829
3830 /* WARNING: this file should *not* be used by applications. It is
3831 part of the implementation of the compression library and is
3832 subject to change. Applications should only use zlib.h.
3833 */
3834
3835 /* Huffman code lookup table entry--this entry is four bytes for machines
3836 that have 16-bit pointers (e.g. PC's in the small or medium model). */
3837
3838 typedef struct inflate_huft_s FAR inflate_huft;
3839
3840 struct inflate_huft_s {
3841 union {
3842 struct {
3843 Byte Exop; /* number of extra bits or operation */
3844 Byte Bits; /* number of bits in this code or subcode */
3845 } what;
3846 uInt pad; /* pad structure to a power of 2 (4 bytes for */
3847 } word; /* 16-bit, 8 bytes for 32-bit int's) */
3848 uInt base; /* literal, length base, distance base,
3849 or table offset */
3850 };
3851
3852 /* Maximum size of dynamic tree. The maximum found in a long but non-
3853 exhaustive search was 1004 huft structures (850 for length/literals
3854 and 154 for distances, the latter actually the result of an
3855 exhaustive search). The actual maximum is not known, but the
3856 value below is more than safe. */
3857 #define MANY 1440
3858
3859 extern int inflate_trees_bits __P((
3860 uIntf *, /* 19 code lengths */
3861 uIntf *, /* bits tree desired/actual depth */
3862 inflate_huft * FAR *, /* bits tree result */
3863 inflate_huft *, /* space for trees */
3864 z_streamp)); /* for messages */
3865
3866 extern int inflate_trees_dynamic __P((
3867 uInt, /* number of literal/length codes */
3868 uInt, /* number of distance codes */
3869 uIntf *, /* that many (total) code lengths */
3870 uIntf *, /* literal desired/actual bit depth */
3871 uIntf *, /* distance desired/actual bit depth */
3872 inflate_huft * FAR *, /* literal/length tree result */
3873 inflate_huft * FAR *, /* distance tree result */
3874 inflate_huft *, /* space for trees */
3875 z_streamp)); /* for messages */
3876
3877 extern int inflate_trees_fixed __P((
3878 uIntf *, /* literal desired/actual bit depth */
3879 uIntf *, /* distance desired/actual bit depth */
3880 inflate_huft * FAR *, /* literal/length tree result */
3881 inflate_huft * FAR *, /* distance tree result */
3882 z_streamp)); /* for memory allocation */
3883 /* --- inftrees.h */
3884
3885 /* +++ infcodes.h */
3886
3887 /* infcodes.h -- header to use infcodes.c
3888 * Copyright (C) 1995-2002 Mark Adler
3889 * For conditions of distribution and use, see copyright notice in zlib.h
3890 */
3891
3892 /* WARNING: this file should *not* be used by applications. It is
3893 part of the implementation of the compression library and is
3894 subject to change. Applications should only use zlib.h.
3895 */
3896
3897 struct inflate_codes_state;
3898 typedef struct inflate_codes_state FAR inflate_codes_statef;
3899
3900 extern inflate_codes_statef *inflate_codes_new __P((
3901 uInt, uInt,
3902 inflate_huft *, inflate_huft *,
3903 z_streamp ));
3904
3905 extern int inflate_codes __P((
3906 inflate_blocks_statef *,
3907 z_streamp ,
3908 int));
3909
3910 extern void inflate_codes_free __P((
3911 inflate_codes_statef *,
3912 z_streamp ));
3913
3914 /* --- infcodes.h */
3915
3916 /* +++ infutil.h */
3917
3918 /* infutil.h -- types and macros common to blocks and codes
3919 * Copyright (C) 1995-2002 Mark Adler
3920 * For conditions of distribution and use, see copyright notice in zlib.h
3921 */
3922
3923 /* WARNING: this file should *not* be used by applications. It is
3924 part of the implementation of the compression library and is
3925 subject to change. Applications should only use zlib.h.
3926 */
3927
3928 #ifndef _INFUTIL_H
3929 #define _INFUTIL_H
3930
3931 typedef enum {
3932 TYPE, /* get type bits (3, including end bit) */
3933 LENS, /* get lengths for stored */
3934 STORED, /* processing stored block */
3935 TABLE, /* get table lengths */
3936 BTREE, /* get bit lengths tree for a dynamic block */
3937 DTREE, /* get length, distance trees for a dynamic block */
3938 CODES, /* processing fixed or dynamic block */
3939 DRY, /* output remaining window bytes */
3940 DONEB, /* finished last block, done */
3941 BADB} /* got a data error--stuck here */
3942 inflate_block_mode;
3943
3944 /* inflate blocks semi-private state */
3945 struct inflate_blocks_state {
3946
3947 /* mode */
3948 inflate_block_mode mode; /* current inflate_block mode */
3949
3950 /* mode dependent information */
3951 union {
3952 uInt left; /* if STORED, bytes left to copy */
3953 struct {
3954 uInt table; /* table lengths (14 bits) */
3955 uInt index; /* index into blens (or border) */
3956 uIntf *blens; /* bit lengths of codes */
3957 uInt bb; /* bit length tree depth */
3958 inflate_huft *tb; /* bit length decoding tree */
3959 } trees; /* if DTREE, decoding info for trees */
3960 struct {
3961 inflate_codes_statef
3962 *codes;
3963 } decode; /* if CODES, current state */
3964 } sub; /* submode */
3965 uInt last; /* true if this block is the last block */
3966
3967 /* mode independent information */
3968 uInt bitk; /* bits in bit buffer */
3969 uLong bitb; /* bit buffer */
3970 inflate_huft *hufts; /* single malloc for tree space */
3971 Bytef *window; /* sliding window */
3972 Bytef *end; /* one byte after sliding window */
3973 Bytef *read; /* window read pointer */
3974 Bytef *write; /* window write pointer */
3975 check_func checkfn; /* check function */
3976 uLong check; /* check on output */
3977
3978 };
3979
3980
3981 /* defines for inflate input/output */
3982 /* update pointers and return */
3983 #define UPDBITS {s->bitb=b;s->bitk=k;}
3984 #define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;}
3985 #define UPDOUT {s->write=q;}
3986 #define UPDATE {UPDBITS UPDIN UPDOUT}
3987 #define LEAVE {UPDATE return inflate_flush(s,z,r);}
3988 /* get bytes and bits */
3989 #define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;}
3990 #define NEEDBYTE {if(n)r=Z_OK;else LEAVE}
3991 #define NEXTBYTE (n--,*p++)
3992 #define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}}
3993 #define DUMPBITS(j) {b>>=(j);k-=(j);}
3994 /* output bytes */
3995 #define WAVAIL (uInt)(q<s->read?s->read-q-1:s->end-q)
3996 #define LOADOUT {q=s->write;m=(uInt)WAVAIL;}
3997 #define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}}
3998 #define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT}
3999 #define NEEDOUT {if(m==0){WRAP if(m==0){FLUSH WRAP if(m==0) LEAVE}}r=Z_OK;}
4000 #define OUTBYTE(a) {*q++=(Byte)(a);m--;}
4001 /* load local pointers */
4002 #define LOAD {LOADIN LOADOUT}
4003
4004 /* masks for lower bits (size given to avoid silly warnings with Visual C++) */
4005 extern uInt inflate_mask[17];
4006
4007 /* copy as much as possible from the sliding window to the output area */
4008 extern int inflate_flush __P((
4009 inflate_blocks_statef *,
4010 z_streamp ,
4011 int));
4012
4013 #ifndef NO_DUMMY_DECL
4014 struct internal_state {int dummy;}; /* for buggy compilers */
4015 #endif
4016
4017 #endif
4018 /* --- infutil.h */
4019
4020 #ifndef NO_DUMMY_DECL
4021 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
4022 #endif
4023
4024 /* simplify the use of the inflate_huft type with some defines */
4025 #define exop word.what.Exop
4026 #define bits word.what.Bits
4027
4028 /* Table for deflate from PKZIP's appnote.txt. */
4029 local const uInt border[] = { /* Order of the bit length code lengths */
4030 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
4031
4032 /*
4033 Notes beyond the 1.93a appnote.txt:
4034
4035 1. Distance pointers never point before the beginning of the output
4036 stream.
4037 2. Distance pointers can point back across blocks, up to 32k away.
4038 3. There is an implied maximum of 7 bits for the bit length table and
4039 15 bits for the actual data.
4040 4. If only one code exists, then it is encoded using one bit. (Zero
4041 would be more efficient, but perhaps a little confusing.) If two
4042 codes exist, they are coded using one bit each (0 and 1).
4043 5. There is no way of sending zero distance codes--a dummy must be
4044 sent if there are none. (History: a pre 2.0 version of PKZIP would
4045 store blocks with no distance codes, but this was discovered to be
4046 too harsh a criterion.) Valid only for 1.93a. 2.04c does allow
4047 zero distance codes, which is sent as one code of zero bits in
4048 length.
4049 6. There are up to 286 literal/length codes. Code 256 represents the
4050 end-of-block. Note however that the static length tree defines
4051 288 codes just to fill out the Huffman codes. Codes 286 and 287
4052 cannot be used though, since there is no length base or extra bits
4053 defined for them. Similarily, there are up to 30 distance codes.
4054 However, static trees define 32 codes (all 5 bits) to fill out the
4055 Huffman codes, but the last two had better not show up in the data.
4056 7. Unzip can check dynamic Huffman blocks for complete code sets.
4057 The exception is that a single code would not be complete (see #4).
4058 8. The five bits following the block type is really the number of
4059 literal codes sent minus 257.
4060 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
4061 (1+6+6). Therefore, to output three times the length, you output
4062 three codes (1+1+1), whereas to output four times the same length,
4063 you only need two codes (1+3). Hmm.
4064 10. In the tree reconstruction algorithm, Code = Code + Increment
4065 only if BitLength(i) is not zero. (Pretty obvious.)
4066 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19)
4067 12. Note: length code 284 can represent 227-258, but length code 285
4068 really is 258. The last length deserves its own, short code
4069 since it gets used a lot in very redundant files. The length
4070 258 is special since 258 - 3 (the min match length) is 255.
4071 13. The literal/length and distance code bit lengths are read as a
4072 single stream of lengths. It is possible (and advantageous) for
4073 a repeat code (16, 17, or 18) to go across the boundary between
4074 the two sets of lengths.
4075 */
4076
4077
4078 void inflate_blocks_reset(s, z, c)
4079 inflate_blocks_statef *s;
4080 z_streamp z;
4081 uLongf *c;
4082 {
4083 if (c != Z_NULL)
4084 *c = s->check;
4085 if (s->mode == BTREE || s->mode == DTREE)
4086 ZFREE(z, s->sub.trees.blens);
4087 if (s->mode == CODES)
4088 inflate_codes_free(s->sub.decode.codes, z);
4089 s->mode = TYPE;
4090 s->bitk = 0;
4091 s->bitb = 0;
4092 s->read = s->write = s->window;
4093 if (s->checkfn != Z_NULL)
4094 z->adler = s->check = (*s->checkfn)(0L, (const Bytef *)Z_NULL, 0);
4095 Tracev((stderr, "inflate: blocks reset\n"));
4096 }
4097
4098
4099 inflate_blocks_statef *inflate_blocks_new(z, c, w)
4100 z_streamp z;
4101 check_func c;
4102 uInt w;
4103 {
4104 inflate_blocks_statef *s;
4105
4106 if ((s = (inflate_blocks_statef *)ZALLOC
4107 (z,1,sizeof(struct inflate_blocks_state))) == Z_NULL)
4108 return s;
4109 if ((s->hufts =
4110 (inflate_huft *)ZALLOC(z, sizeof(inflate_huft), MANY)) == Z_NULL)
4111 {
4112 ZFREE(z, s);
4113 return Z_NULL;
4114 }
4115 if ((s->window = (Bytef *)ZALLOC(z, 1, w)) == Z_NULL)
4116 {
4117 ZFREE(z, s->hufts);
4118 ZFREE(z, s);
4119 return Z_NULL;
4120 }
4121 s->end = s->window + w;
4122 s->checkfn = c;
4123 s->mode = TYPE;
4124 Tracev((stderr, "inflate: blocks allocated\n"));
4125 inflate_blocks_reset(s, z, Z_NULL);
4126 return s;
4127 }
4128
4129
4130 int inflate_blocks(s, z, r)
4131 inflate_blocks_statef *s;
4132 z_streamp z;
4133 int r;
4134 {
4135 uInt t; /* temporary storage */
4136 uLong b; /* bit buffer */
4137 uInt k; /* bits in bit buffer */
4138 Bytef *p; /* input data pointer */
4139 uInt n; /* bytes available there */
4140 Bytef *q; /* output window write pointer */
4141 uInt m; /* bytes to end of window or read pointer */
4142
4143 /* copy input/output information to locals (UPDATE macro restores) */
4144 LOAD
4145
4146 /* process input based on current state */
4147 while (1) switch (s->mode)
4148 {
4149 case TYPE:
4150 NEEDBITS(3)
4151 t = (uInt)b & 7;
4152 s->last = t & 1;
4153 switch (t >> 1)
4154 {
4155 case 0: /* stored */
4156 Tracev((stderr, "inflate: stored block%s\n",
4157 s->last ? " (last)" : ""));
4158 DUMPBITS(3)
4159 t = k & 7; /* go to byte boundary */
4160 DUMPBITS(t)
4161 s->mode = LENS; /* get length of stored block */
4162 break;
4163 case 1: /* fixed */
4164 Tracev((stderr, "inflate: fixed codes block%s\n",
4165 s->last ? " (last)" : ""));
4166 {
4167 uInt bl, bd;
4168 inflate_huft *tl, *td;
4169
4170 inflate_trees_fixed(&bl, &bd, &tl, &td, z);
4171 s->sub.decode.codes = inflate_codes_new(bl, bd, tl, td, z);
4172 if (s->sub.decode.codes == Z_NULL)
4173 {
4174 r = Z_MEM_ERROR;
4175 LEAVE
4176 }
4177 }
4178 DUMPBITS(3)
4179 s->mode = CODES;
4180 break;
4181 case 2: /* dynamic */
4182 Tracev((stderr, "inflate: dynamic codes block%s\n",
4183 s->last ? " (last)" : ""));
4184 DUMPBITS(3)
4185 s->mode = TABLE;
4186 break;
4187 case 3: /* illegal */
4188 DUMPBITS(3)
4189 s->mode = BADB;
4190 z->msg = (char*)"invalid block type";
4191 r = Z_DATA_ERROR;
4192 LEAVE
4193 }
4194 break;
4195 case LENS:
4196 NEEDBITS(32)
4197 if ((((~b) >> 16) & 0xffff) != (b & 0xffff))
4198 {
4199 s->mode = BADB;
4200 z->msg = (char*)"invalid stored block lengths";
4201 r = Z_DATA_ERROR;
4202 LEAVE
4203 }
4204 s->sub.left = (uInt)b & 0xffff;
4205 b = k = 0; /* dump bits */
4206 Tracev((stderr, "inflate: stored length %u\n", s->sub.left));
4207 s->mode = s->sub.left ? STORED : (s->last ? DRY : TYPE);
4208 break;
4209 case STORED:
4210 if (n == 0)
4211 LEAVE
4212 NEEDOUT
4213 t = s->sub.left;
4214 if (t > n) t = n;
4215 if (t > m) t = m;
4216 zmemcpy(q, p, t);
4217 p += t; n -= t;
4218 q += t; m -= t;
4219 if ((s->sub.left -= t) != 0)
4220 break;
4221 Tracev((stderr, "inflate: stored end, %lu total out\n",
4222 z->total_out + (q >= s->read ? q - s->read :
4223 (s->end - s->read) + (q - s->window))));
4224 s->mode = s->last ? DRY : TYPE;
4225 break;
4226 case TABLE:
4227 NEEDBITS(14)
4228 s->sub.trees.table = t = (uInt)b & 0x3fff;
4229 #ifndef PKZIP_BUG_WORKAROUND
4230 if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29)
4231 {
4232 s->mode = BADB;
4233 z->msg = (char*)"too many length or distance symbols";
4234 r = Z_DATA_ERROR;
4235 LEAVE
4236 }
4237 #endif
4238 t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
4239 if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL)
4240 {
4241 r = Z_MEM_ERROR;
4242 LEAVE
4243 }
4244 DUMPBITS(14)
4245 s->sub.trees.index = 0;
4246 Tracev((stderr, "inflate: table sizes ok\n"));
4247 s->mode = BTREE;
4248 case BTREE:
4249 while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10))
4250 {
4251 NEEDBITS(3)
4252 s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7;
4253 DUMPBITS(3)
4254 }
4255 while (s->sub.trees.index < 19)
4256 s->sub.trees.blens[border[s->sub.trees.index++]] = 0;
4257 s->sub.trees.bb = 7;
4258 t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb,
4259 &s->sub.trees.tb, s->hufts, z);
4260 if (t != Z_OK)
4261 {
4262 r = t;
4263 if (r == Z_DATA_ERROR)
4264 {
4265 ZFREE(z, s->sub.trees.blens);
4266 s->mode = BADB;
4267 }
4268 LEAVE
4269 }
4270 s->sub.trees.index = 0;
4271 Tracev((stderr, "inflate: bits tree ok\n"));
4272 s->mode = DTREE;
4273 case DTREE:
4274 while (t = s->sub.trees.table,
4275 s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f))
4276 {
4277 inflate_huft *h;
4278 uInt i, j, c;
4279
4280 t = s->sub.trees.bb;
4281 NEEDBITS(t)
4282 h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]);
4283 t = h->bits;
4284 c = h->base;
4285 if (c < 16)
4286 {
4287 DUMPBITS(t)
4288 s->sub.trees.blens[s->sub.trees.index++] = c;
4289 }
4290 else /* c == 16..18 */
4291 {
4292 i = c == 18 ? 7 : c - 14;
4293 j = c == 18 ? 11 : 3;
4294 NEEDBITS(t + i)
4295 DUMPBITS(t)
4296 j += (uInt)b & inflate_mask[i];
4297 DUMPBITS(i)
4298 i = s->sub.trees.index;
4299 t = s->sub.trees.table;
4300 if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) ||
4301 (c == 16 && i < 1))
4302 {
4303 ZFREE(z, s->sub.trees.blens);
4304 s->mode = BADB;
4305 z->msg = (char*)"invalid bit length repeat";
4306 r = Z_DATA_ERROR;
4307 LEAVE
4308 }
4309 c = c == 16 ? s->sub.trees.blens[i - 1] : 0;
4310 do {
4311 s->sub.trees.blens[i++] = c;
4312 } while (--j);
4313 s->sub.trees.index = i;
4314 }
4315 }
4316 s->sub.trees.tb = Z_NULL;
4317 {
4318 uInt bl, bd;
4319 inflate_huft *tl, *td;
4320 inflate_codes_statef *c;
4321
4322 bl = 9; /* must be <= 9 for lookahead assumptions */
4323 bd = 6; /* must be <= 9 for lookahead assumptions */
4324 t = s->sub.trees.table;
4325 t = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f),
4326 s->sub.trees.blens, &bl, &bd, &tl, &td,
4327 s->hufts, z);
4328 if (t != Z_OK)
4329 {
4330 if (t == (uInt)Z_DATA_ERROR)
4331 {
4332 ZFREE(z, s->sub.trees.blens);
4333 s->mode = BADB;
4334 }
4335 r = t;
4336 LEAVE
4337 }
4338 Tracev((stderr, "inflate: trees ok\n"));
4339 if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL)
4340 {
4341 r = Z_MEM_ERROR;
4342 LEAVE
4343 }
4344 s->sub.decode.codes = c;
4345 }
4346 ZFREE(z, s->sub.trees.blens);
4347 s->mode = CODES;
4348 case CODES:
4349 UPDATE
4350 if ((r = inflate_codes(s, z, r)) != Z_STREAM_END)
4351 return inflate_flush(s, z, r);
4352 r = Z_OK;
4353 inflate_codes_free(s->sub.decode.codes, z);
4354 LOAD
4355 Tracev((stderr, "inflate: codes end, %lu total out\n",
4356 z->total_out + (q >= s->read ? q - s->read :
4357 (s->end - s->read) + (q - s->window))));
4358 if (!s->last)
4359 {
4360 s->mode = TYPE;
4361 break;
4362 }
4363 s->mode = DRY;
4364 case DRY:
4365 FLUSH
4366 if (s->read != s->write)
4367 LEAVE
4368 s->mode = DONEB;
4369 case DONEB:
4370 r = Z_STREAM_END;
4371 LEAVE
4372 case BADB:
4373 r = Z_DATA_ERROR;
4374 LEAVE
4375 default:
4376 r = Z_STREAM_ERROR;
4377 LEAVE
4378 }
4379 }
4380
4381
4382 int inflate_blocks_free(s, z)
4383 inflate_blocks_statef *s;
4384 z_streamp z;
4385 {
4386 inflate_blocks_reset(s, z, Z_NULL);
4387 ZFREE(z, s->window);
4388 ZFREE(z, s->hufts);
4389 ZFREE(z, s);
4390 Tracev((stderr, "inflate: blocks freed\n"));
4391 return Z_OK;
4392 }
4393
4394
4395 #if 0
4396 void inflate_set_dictionary(s, d, n)
4397 inflate_blocks_statef *s;
4398 const Bytef *d;
4399 uInt n;
4400 {
4401 zmemcpy(s->window, d, n);
4402 s->read = s->write = s->window + n;
4403 }
4404 #endif
4405
4406 /*
4407 * This subroutine adds the data at next_in/avail_in to the output history
4408 * without performing any output. The output buffer must be "caught up";
4409 * i.e. no pending output (hence s->read equals s->write), and the state must
4410 * be BLOCKS (i.e. we should be willing to see the start of a series of
4411 * BLOCKS). On exit, the output will also be caught up, and the checksum
4412 * will have been updated if need be.
4413 */
4414 int inflate_addhistory(s, z)
4415 inflate_blocks_statef *s;
4416 z_stream *z;
4417 {
4418 uLong b; /* bit buffer */ /* NOT USED HERE */
4419 uInt k; /* bits in bit buffer */ /* NOT USED HERE */
4420 uInt t; /* temporary storage */
4421 Bytef *p; /* input data pointer */
4422 uInt n; /* bytes available there */
4423 Bytef *q; /* output window write pointer */
4424 uInt m; /* bytes to end of window or read pointer */
4425
4426 if (s->read != s->write)
4427 return Z_STREAM_ERROR;
4428 if (s->mode != TYPE)
4429 return Z_DATA_ERROR;
4430
4431 /* we're ready to rock */
4432 LOAD
4433 /* while there is input ready, copy to output buffer, moving
4434 * pointers as needed.
4435 */
4436 while (n) {
4437 t = n; /* how many to do */
4438 /* is there room until end of buffer? */
4439 if (t > m) t = m;
4440 /* update check information */
4441 if (s->checkfn != Z_NULL)
4442 s->check = (*s->checkfn)(s->check, q, t);
4443 zmemcpy(q, p, t);
4444 q += t;
4445 p += t;
4446 n -= t;
4447 z->total_out += t;
4448 s->read = q; /* drag read pointer forward */
4449 /* WWRAP */ /* expand WWRAP macro by hand to handle s->read */
4450 if (q == s->end) {
4451 s->read = q = s->window;
4452 m = WAVAIL;
4453 }
4454 }
4455 UPDATE
4456 return Z_OK;
4457 }
4458
4459
4460 /*
4461 * At the end of a Deflate-compressed PPP packet, we expect to have seen
4462 * a `stored' block type value but not the (zero) length bytes.
4463 */
4464 int inflate_packet_flush(s)
4465 inflate_blocks_statef *s;
4466 {
4467 if (s->mode != LENS)
4468 return Z_DATA_ERROR;
4469 s->mode = TYPE;
4470 return Z_OK;
4471 }
4472
4473 /* Returns true if inflate is currently at the end of a block generated
4474 * by Z_SYNC_FLUSH or Z_FULL_FLUSH.
4475 * IN assertion: s != Z_NULL
4476 */
4477 #if 0
4478 int inflate_blocks_sync_point(s)
4479 inflate_blocks_statef *s;
4480 {
4481 return s->mode == LENS;
4482 }
4483 #endif
4484 /* --- infblock.c */
4485
4486
4487 /* +++ inftrees.c */
4488
4489 /* inftrees.c -- generate Huffman trees for efficient decoding
4490 * Copyright (C) 1995-2002 Mark Adler
4491 * For conditions of distribution and use, see copyright notice in zlib.h
4492 */
4493
4494 /* #include "zutil.h" */
4495 /* #include "inftrees.h" */
4496
4497 #if !defined(BUILDFIXED) && !defined(STDC)
4498 # define BUILDFIXED /* non ANSI compilers may not accept inffixed.h */
4499 #endif
4500
4501 const char inflate_copyright[] =
4502 " inflate 1.1.4 Copyright 1995-2002 Mark Adler ";
4503 /*
4504 If you use the zlib library in a product, an acknowledgment is welcome
4505 in the documentation of your product. If for some reason you cannot
4506 include such an acknowledgment, I would appreciate that you keep this
4507 copyright string in the executable of your product.
4508 */
4509
4510 #ifndef NO_DUMMY_DECL
4511 struct internal_state {int dummy;}; /* for buggy compilers */
4512 #endif
4513
4514 /* simplify the use of the inflate_huft type with some defines */
4515 #define exop word.what.Exop
4516 #define bits word.what.Bits
4517
4518
4519 local int huft_build __P((
4520 uIntf *, /* code lengths in bits */
4521 uInt, /* number of codes */
4522 uInt, /* number of "simple" codes */
4523 const uIntf *, /* list of base values for non-simple codes */
4524 const uIntf *, /* list of extra bits for non-simple codes */
4525 inflate_huft * FAR*,/* result: starting table */
4526 uIntf *, /* maximum lookup bits (returns actual) */
4527 inflate_huft *, /* space for trees */
4528 uInt *, /* hufts used in space */
4529 uIntf * )); /* space for values */
4530
4531 /* Tables for deflate from PKZIP's appnote.txt. */
4532 local const uInt cplens[31] = { /* Copy lengths for literal codes 257..285 */
4533 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
4534 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
4535 /* see note #13 above about 258 */
4536 local const uInt cplext[31] = { /* Extra bits for literal codes 257..285 */
4537 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
4538 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 112, 112}; /* 112==invalid */
4539 local const uInt cpdist[30] = { /* Copy offsets for distance codes 0..29 */
4540 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
4541 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
4542 8193, 12289, 16385, 24577};
4543 local const uInt cpdext[30] = { /* Extra bits for distance codes */
4544 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
4545 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
4546 12, 12, 13, 13};
4547
4548 /*
4549 Huffman code decoding is performed using a multi-level table lookup.
4550 The fastest way to decode is to simply build a lookup table whose
4551 size is determined by the longest code. However, the time it takes
4552 to build this table can also be a factor if the data being decoded
4553 is not very long. The most common codes are necessarily the
4554 shortest codes, so those codes dominate the decoding time, and hence
4555 the speed. The idea is you can have a shorter table that decodes the
4556 shorter, more probable codes, and then point to subsidiary tables for
4557 the longer codes. The time it costs to decode the longer codes is
4558 then traded against the time it takes to make longer tables.
4559
4560 This results of this trade are in the variables lbits and dbits
4561 below. lbits is the number of bits the first level table for literal/
4562 length codes can decode in one step, and dbits is the same thing for
4563 the distance codes. Subsequent tables are also less than or equal to
4564 those sizes. These values may be adjusted either when all of the
4565 codes are shorter than that, in which case the longest code length in
4566 bits is used, or when the shortest code is *longer* than the requested
4567 table size, in which case the length of the shortest code in bits is
4568 used.
4569
4570 There are two different values for the two tables, since they code a
4571 different number of possibilities each. The literal/length table
4572 codes 286 possible values, or in a flat code, a little over eight
4573 bits. The distance table codes 30 possible values, or a little less
4574 than five bits, flat. The optimum values for speed end up being
4575 about one bit more than those, so lbits is 8+1 and dbits is 5+1.
4576 The optimum values may differ though from machine to machine, and
4577 possibly even between compilers. Your mileage may vary.
4578 */
4579
4580
4581 /* If BMAX needs to be larger than 16, then h and x[] should be uLong. */
4582 #define BMAX 15 /* maximum bit length of any code */
4583
4584 local int huft_build(b, n, s, d, e, t, m, hp, hn, v)
4585 uIntf *b; /* code lengths in bits (all assumed <= BMAX) */
4586 uInt n; /* number of codes (assumed <= 288) */
4587 uInt s; /* number of simple-valued codes (0..s-1) */
4588 const uIntf *d; /* list of base values for non-simple codes */
4589 const uIntf *e; /* list of extra bits for non-simple codes */
4590 inflate_huft * FAR *t; /* result: starting table */
4591 uIntf *m; /* maximum lookup bits, returns actual */
4592 inflate_huft *hp; /* space for trees */
4593 uInt *hn; /* hufts used in space */
4594 uIntf *v; /* working area: values in order of bit length */
4595 /* Given a list of code lengths and a maximum table size, make a set of
4596 tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR
4597 if the given code set is incomplete (the tables are still built in this
4598 case), or Z_DATA_ERROR if the input is invalid. */
4599 {
4600
4601 uInt a; /* counter for codes of length k */
4602 uInt c[BMAX+1]; /* bit length count table */
4603 uInt f; /* i repeats in table every f entries */
4604 int g; /* maximum code length */
4605 int h; /* table level */
4606 uInt i; /* counter, current code */
4607 uInt j; /* counter */
4608 int k; /* number of bits in current code */
4609 int l; /* bits per table (returned in m) */
4610 uInt mask; /* (1 << w) - 1, to avoid cc -O bug on HP */
4611 uIntf *p; /* pointer into c[], b[], or v[] */
4612 inflate_huft *q; /* points to current table */
4613 struct inflate_huft_s r; /* table entry for structure assignment */
4614 inflate_huft *u[BMAX]; /* table stack */
4615 int w; /* bits before this table == (l * h) */
4616 uInt x[BMAX+1]; /* bit offsets, then code stack */
4617 uIntf *xp; /* pointer into x */
4618 int y; /* number of dummy codes added */
4619 uInt z; /* number of entries in current table */
4620
4621
4622 /* Generate counts for each bit length */
4623 p = c;
4624 #define C0 *p++ = 0;
4625 #define C2 C0 C0 C0 C0
4626 #define C4 C2 C2 C2 C2
4627 C4 /* clear c[]--assume BMAX+1 is 16 */
4628 p = b; i = n;
4629 do {
4630 c[*p++]++; /* assume all entries <= BMAX */
4631 } while (--i);
4632 if (c[0] == n) /* null input--all zero length codes */
4633 {
4634 *t = (inflate_huft *)Z_NULL;
4635 *m = 0;
4636 return Z_OK;
4637 }
4638
4639
4640 /* Find minimum and maximum length, bound *m by those */
4641 l = *m;
4642 for (j = 1; j <= BMAX; j++)
4643 if (c[j])
4644 break;
4645 k = j; /* minimum code length */
4646 if ((uInt)l < j)
4647 l = j;
4648 for (i = BMAX; i; i--)
4649 if (c[i])
4650 break;
4651 g = i; /* maximum code length */
4652 if ((uInt)l > i)
4653 l = i;
4654 *m = l;
4655
4656
4657 /* Adjust last length count to fill out codes, if needed */
4658 for (y = 1 << j; j < i; j++, y <<= 1)
4659 if ((y -= c[j]) < 0)
4660 return Z_DATA_ERROR;
4661 if ((y -= c[i]) < 0)
4662 return Z_DATA_ERROR;
4663 c[i] += y;
4664
4665
4666 /* Generate starting offsets into the value table for each length */
4667 x[1] = j = 0;
4668 p = c + 1; xp = x + 2;
4669 while (--i) { /* note that i == g from above */
4670 *xp++ = (j += *p++);
4671 }
4672
4673
4674 /* Make a table of values in order of bit lengths */
4675 p = b; i = 0;
4676 do {
4677 if ((j = *p++) != 0)
4678 v[x[j]++] = i;
4679 } while (++i < n);
4680 n = x[g]; /* set n to length of v */
4681
4682
4683 /* Generate the Huffman codes and for each, make the table entries */
4684 x[0] = i = 0; /* first Huffman code is zero */
4685 p = v; /* grab values in bit order */
4686 h = -1; /* no tables yet--level -1 */
4687 w = -l; /* bits decoded == (l * h) */
4688 u[0] = (inflate_huft *)Z_NULL; /* just to keep compilers happy */
4689 q = (inflate_huft *)Z_NULL; /* ditto */
4690 z = 0; /* ditto */
4691
4692 /* go through the bit lengths (k already is bits in shortest code) */
4693 for (; k <= g; k++)
4694 {
4695 a = c[k];
4696 while (a--)
4697 {
4698 /* here i is the Huffman code of length k bits for value *p */
4699 /* make tables up to required level */
4700 while (k > w + l)
4701 {
4702 h++;
4703 w += l; /* previous table always l bits */
4704
4705 /* compute minimum size table less than or equal to l bits */
4706 z = g - w;
4707 z = z > (uInt)l ? l : z; /* table size upper limit */
4708 if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */
4709 { /* too few codes for k-w bit table */
4710 f -= a + 1; /* deduct codes from patterns left */
4711 xp = c + k;
4712 if (j < z)
4713 while (++j < z) /* try smaller tables up to z bits */
4714 {
4715 if ((f <<= 1) <= *++xp)
4716 break; /* enough codes to use up j bits */
4717 f -= *xp; /* else deduct codes from patterns */
4718 }
4719 }
4720 z = 1 << j; /* table entries for j-bit table */
4721
4722 /* allocate new table */
4723 if (*hn + z > MANY) /* (note: doesn't matter for fixed) */
4724 return Z_DATA_ERROR; /* overflow of MANY */
4725 u[h] = q = hp + *hn;
4726 *hn += z;
4727
4728 /* connect to last table, if there is one */
4729 if (h)
4730 {
4731 x[h] = i; /* save pattern for backing up */
4732 r.bits = (Byte)l; /* bits to dump before this table */
4733 r.exop = (Byte)j; /* bits in this table */
4734 j = i >> (w - l);
4735 r.base = (uInt)(q - u[h-1] - j); /* offset to this table */
4736 u[h-1][j] = r; /* connect to last table */
4737 }
4738 else
4739 *t = q; /* first table is returned result */
4740 }
4741
4742 /* set up table entry in r */
4743 r.bits = (Byte)(k - w);
4744 if (p >= v + n)
4745 r.exop = 128 + 64; /* out of values--invalid code */
4746 else if (*p < s)
4747 {
4748 r.exop = (Byte)(*p < 256 ? 0 : 32 + 64); /* 256 is end-of-block */
4749 r.base = *p++; /* simple code is just the value */
4750 }
4751 else
4752 {
4753 r.exop = (Byte)(e[*p - s] + 16 + 64);/* non-simple--look up in lists */
4754 r.base = d[*p++ - s];
4755 }
4756
4757 /* fill code-like entries with r */
4758 f = 1 << (k - w);
4759 for (j = i >> w; j < z; j += f)
4760 q[j] = r;
4761
4762 /* backwards increment the k-bit code i */
4763 for (j = 1 << (k - 1); i & j; j >>= 1)
4764 i ^= j;
4765 i ^= j;
4766
4767 /* backup over finished tables */
4768 mask = (1 << w) - 1; /* needed on HP, cc -O bug */
4769 while ((i & mask) != x[h])
4770 {
4771 h--; /* don't need to update q */
4772 w -= l;
4773 mask = (1 << w) - 1;
4774 }
4775 }
4776 }
4777
4778
4779 /* Return Z_BUF_ERROR if we were given an incomplete table */
4780 return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK;
4781 }
4782
4783
4784 int inflate_trees_bits(c, bb, tb, hp, z)
4785 uIntf *c; /* 19 code lengths */
4786 uIntf *bb; /* bits tree desired/actual depth */
4787 inflate_huft * FAR *tb; /* bits tree result */
4788 inflate_huft *hp; /* space for trees */
4789 z_streamp z; /* for messages */
4790 {
4791 int r;
4792 uInt hn = 0; /* hufts used in space */
4793 uIntf *v; /* work area for huft_build */
4794
4795 if ((v = (uIntf*)ZALLOC(z, 19, sizeof(uInt))) == Z_NULL)
4796 return Z_MEM_ERROR;
4797 r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL,
4798 tb, bb, hp, &hn, v);
4799 if (r == Z_DATA_ERROR)
4800 z->msg = (char*)"oversubscribed dynamic bit lengths tree";
4801 else if (r == Z_BUF_ERROR || *bb == 0)
4802 {
4803 z->msg = (char*)"incomplete dynamic bit lengths tree";
4804 r = Z_DATA_ERROR;
4805 }
4806 ZFREE(z, v);
4807 return r;
4808 }
4809
4810
4811 int inflate_trees_dynamic(nl, nd, c, bl, bd, tl, td, hp, z)
4812 uInt nl; /* number of literal/length codes */
4813 uInt nd; /* number of distance codes */
4814 uIntf *c; /* that many (total) code lengths */
4815 uIntf *bl; /* literal desired/actual bit depth */
4816 uIntf *bd; /* distance desired/actual bit depth */
4817 inflate_huft * FAR *tl; /* literal/length tree result */
4818 inflate_huft * FAR *td; /* distance tree result */
4819 inflate_huft *hp; /* space for trees */
4820 z_streamp z; /* for messages */
4821 {
4822 int r;
4823 uInt hn = 0; /* hufts used in space */
4824 uIntf *v; /* work area for huft_build */
4825
4826 /* allocate work area */
4827 if ((v = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
4828 return Z_MEM_ERROR;
4829
4830 /* build literal/length tree */
4831 r = huft_build(c, nl, 257, cplens, cplext, tl, bl, hp, &hn, v);
4832 if (r != Z_OK || *bl == 0)
4833 {
4834 if (r == Z_DATA_ERROR)
4835 z->msg = (char*)"oversubscribed literal/length tree";
4836 else if (r != Z_MEM_ERROR)
4837 {
4838 z->msg = (char*)"incomplete literal/length tree";
4839 r = Z_DATA_ERROR;
4840 }
4841 ZFREE(z, v);
4842 return r;
4843 }
4844
4845 /* build distance tree */
4846 r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, hp, &hn, v);
4847 if (r != Z_OK || (*bd == 0 && nl > 257))
4848 {
4849 if (r == Z_DATA_ERROR)
4850 z->msg = (char*)"oversubscribed distance tree";
4851 else if (r == Z_BUF_ERROR) {
4852 #ifdef PKZIP_BUG_WORKAROUND
4853 r = Z_OK;
4854 }
4855 #else
4856 z->msg = (char*)"incomplete distance tree";
4857 r = Z_DATA_ERROR;
4858 }
4859 else if (r != Z_MEM_ERROR)
4860 {
4861 z->msg = (char*)"empty distance tree with lengths";
4862 r = Z_DATA_ERROR;
4863 }
4864 ZFREE(z, v);
4865 return r;
4866 #endif
4867 }
4868
4869 /* done */
4870 ZFREE(z, v);
4871 return Z_OK;
4872 }
4873
4874
4875 /* build fixed tables only once--keep them here */
4876 #ifdef BUILDFIXED
4877 local int fixed_built = 0;
4878 #define FIXEDH 544 /* number of hufts used by fixed tables */
4879 local inflate_huft fixed_mem[FIXEDH];
4880 local uInt fixed_bl;
4881 local uInt fixed_bd;
4882 local inflate_huft *fixed_tl;
4883 local inflate_huft *fixed_td;
4884 #else
4885
4886 /* +++ inffixed.h */
4887 /* inffixed.h -- table for decoding fixed codes
4888 * Generated automatically by the maketree.c program
4889 */
4890
4891 /* WARNING: this file should *not* be used by applications. It is
4892 part of the implementation of the compression library and is
4893 subject to change. Applications should only use zlib.h.
4894 */
4895
4896 local uInt fixed_bl = 9;
4897 local uInt fixed_bd = 5;
4898 local inflate_huft fixed_tl[] = {
4899 {{{96,7}},256}, {{{0,8}},80}, {{{0,8}},16}, {{{84,8}},115},
4900 {{{82,7}},31}, {{{0,8}},112}, {{{0,8}},48}, {{{0,9}},192},
4901 {{{80,7}},10}, {{{0,8}},96}, {{{0,8}},32}, {{{0,9}},160},
4902 {{{0,8}},0}, {{{0,8}},128}, {{{0,8}},64}, {{{0,9}},224},
4903 {{{80,7}},6}, {{{0,8}},88}, {{{0,8}},24}, {{{0,9}},144},
4904 {{{83,7}},59}, {{{0,8}},120}, {{{0,8}},56}, {{{0,9}},208},
4905 {{{81,7}},17}, {{{0,8}},104}, {{{0,8}},40}, {{{0,9}},176},
4906 {{{0,8}},8}, {{{0,8}},136}, {{{0,8}},72}, {{{0,9}},240},
4907 {{{80,7}},4}, {{{0,8}},84}, {{{0,8}},20}, {{{85,8}},227},
4908 {{{83,7}},43}, {{{0,8}},116}, {{{0,8}},52}, {{{0,9}},200},
4909 {{{81,7}},13}, {{{0,8}},100}, {{{0,8}},36}, {{{0,9}},168},
4910 {{{0,8}},4}, {{{0,8}},132}, {{{0,8}},68}, {{{0,9}},232},
4911 {{{80,7}},8}, {{{0,8}},92}, {{{0,8}},28}, {{{0,9}},152},
4912 {{{84,7}},83}, {{{0,8}},124}, {{{0,8}},60}, {{{0,9}},216},
4913 {{{82,7}},23}, {{{0,8}},108}, {{{0,8}},44}, {{{0,9}},184},
4914 {{{0,8}},12}, {{{0,8}},140}, {{{0,8}},76}, {{{0,9}},248},
4915 {{{80,7}},3}, {{{0,8}},82}, {{{0,8}},18}, {{{85,8}},163},
4916 {{{83,7}},35}, {{{0,8}},114}, {{{0,8}},50}, {{{0,9}},196},
4917 {{{81,7}},11}, {{{0,8}},98}, {{{0,8}},34}, {{{0,9}},164},
4918 {{{0,8}},2}, {{{0,8}},130}, {{{0,8}},66}, {{{0,9}},228},
4919 {{{80,7}},7}, {{{0,8}},90}, {{{0,8}},26}, {{{0,9}},148},
4920 {{{84,7}},67}, {{{0,8}},122}, {{{0,8}},58}, {{{0,9}},212},
4921 {{{82,7}},19}, {{{0,8}},106}, {{{0,8}},42}, {{{0,9}},180},
4922 {{{0,8}},10}, {{{0,8}},138}, {{{0,8}},74}, {{{0,9}},244},
4923 {{{80,7}},5}, {{{0,8}},86}, {{{0,8}},22}, {{{192,8}},0},
4924 {{{83,7}},51}, {{{0,8}},118}, {{{0,8}},54}, {{{0,9}},204},
4925 {{{81,7}},15}, {{{0,8}},102}, {{{0,8}},38}, {{{0,9}},172},
4926 {{{0,8}},6}, {{{0,8}},134}, {{{0,8}},70}, {{{0,9}},236},
4927 {{{80,7}},9}, {{{0,8}},94}, {{{0,8}},30}, {{{0,9}},156},
4928 {{{84,7}},99}, {{{0,8}},126}, {{{0,8}},62}, {{{0,9}},220},
4929 {{{82,7}},27}, {{{0,8}},110}, {{{0,8}},46}, {{{0,9}},188},
4930 {{{0,8}},14}, {{{0,8}},142}, {{{0,8}},78}, {{{0,9}},252},
4931 {{{96,7}},256}, {{{0,8}},81}, {{{0,8}},17}, {{{85,8}},131},
4932 {{{82,7}},31}, {{{0,8}},113}, {{{0,8}},49}, {{{0,9}},194},
4933 {{{80,7}},10}, {{{0,8}},97}, {{{0,8}},33}, {{{0,9}},162},
4934 {{{0,8}},1}, {{{0,8}},129}, {{{0,8}},65}, {{{0,9}},226},
4935 {{{80,7}},6}, {{{0,8}},89}, {{{0,8}},25}, {{{0,9}},146},
4936 {{{83,7}},59}, {{{0,8}},121}, {{{0,8}},57}, {{{0,9}},210},
4937 {{{81,7}},17}, {{{0,8}},105}, {{{0,8}},41}, {{{0,9}},178},
4938 {{{0,8}},9}, {{{0,8}},137}, {{{0,8}},73}, {{{0,9}},242},
4939 {{{80,7}},4}, {{{0,8}},85}, {{{0,8}},21}, {{{80,8}},258},
4940 {{{83,7}},43}, {{{0,8}},117}, {{{0,8}},53}, {{{0,9}},202},
4941 {{{81,7}},13}, {{{0,8}},101}, {{{0,8}},37}, {{{0,9}},170},
4942 {{{0,8}},5}, {{{0,8}},133}, {{{0,8}},69}, {{{0,9}},234},
4943 {{{80,7}},8}, {{{0,8}},93}, {{{0,8}},29}, {{{0,9}},154},
4944 {{{84,7}},83}, {{{0,8}},125}, {{{0,8}},61}, {{{0,9}},218},
4945 {{{82,7}},23}, {{{0,8}},109}, {{{0,8}},45}, {{{0,9}},186},
4946 {{{0,8}},13}, {{{0,8}},141}, {{{0,8}},77}, {{{0,9}},250},
4947 {{{80,7}},3}, {{{0,8}},83}, {{{0,8}},19}, {{{85,8}},195},
4948 {{{83,7}},35}, {{{0,8}},115}, {{{0,8}},51}, {{{0,9}},198},
4949 {{{81,7}},11}, {{{0,8}},99}, {{{0,8}},35}, {{{0,9}},166},
4950 {{{0,8}},3}, {{{0,8}},131}, {{{0,8}},67}, {{{0,9}},230},
4951 {{{80,7}},7}, {{{0,8}},91}, {{{0,8}},27}, {{{0,9}},150},
4952 {{{84,7}},67}, {{{0,8}},123}, {{{0,8}},59}, {{{0,9}},214},
4953 {{{82,7}},19}, {{{0,8}},107}, {{{0,8}},43}, {{{0,9}},182},
4954 {{{0,8}},11}, {{{0,8}},139}, {{{0,8}},75}, {{{0,9}},246},
4955 {{{80,7}},5}, {{{0,8}},87}, {{{0,8}},23}, {{{192,8}},0},
4956 {{{83,7}},51}, {{{0,8}},119}, {{{0,8}},55}, {{{0,9}},206},
4957 {{{81,7}},15}, {{{0,8}},103}, {{{0,8}},39}, {{{0,9}},174},
4958 {{{0,8}},7}, {{{0,8}},135}, {{{0,8}},71}, {{{0,9}},238},
4959 {{{80,7}},9}, {{{0,8}},95}, {{{0,8}},31}, {{{0,9}},158},
4960 {{{84,7}},99}, {{{0,8}},127}, {{{0,8}},63}, {{{0,9}},222},
4961 {{{82,7}},27}, {{{0,8}},111}, {{{0,8}},47}, {{{0,9}},190},
4962 {{{0,8}},15}, {{{0,8}},143}, {{{0,8}},79}, {{{0,9}},254},
4963 {{{96,7}},256}, {{{0,8}},80}, {{{0,8}},16}, {{{84,8}},115},
4964 {{{82,7}},31}, {{{0,8}},112}, {{{0,8}},48}, {{{0,9}},193},
4965 {{{80,7}},10}, {{{0,8}},96}, {{{0,8}},32}, {{{0,9}},161},
4966 {{{0,8}},0}, {{{0,8}},128}, {{{0,8}},64}, {{{0,9}},225},
4967 {{{80,7}},6}, {{{0,8}},88}, {{{0,8}},24}, {{{0,9}},145},
4968 {{{83,7}},59}, {{{0,8}},120}, {{{0,8}},56}, {{{0,9}},209},
4969 {{{81,7}},17}, {{{0,8}},104}, {{{0,8}},40}, {{{0,9}},177},
4970 {{{0,8}},8}, {{{0,8}},136}, {{{0,8}},72}, {{{0,9}},241},
4971 {{{80,7}},4}, {{{0,8}},84}, {{{0,8}},20}, {{{85,8}},227},
4972 {{{83,7}},43}, {{{0,8}},116}, {{{0,8}},52}, {{{0,9}},201},
4973 {{{81,7}},13}, {{{0,8}},100}, {{{0,8}},36}, {{{0,9}},169},
4974 {{{0,8}},4}, {{{0,8}},132}, {{{0,8}},68}, {{{0,9}},233},
4975 {{{80,7}},8}, {{{0,8}},92}, {{{0,8}},28}, {{{0,9}},153},
4976 {{{84,7}},83}, {{{0,8}},124}, {{{0,8}},60}, {{{0,9}},217},
4977 {{{82,7}},23}, {{{0,8}},108}, {{{0,8}},44}, {{{0,9}},185},
4978 {{{0,8}},12}, {{{0,8}},140}, {{{0,8}},76}, {{{0,9}},249},
4979 {{{80,7}},3}, {{{0,8}},82}, {{{0,8}},18}, {{{85,8}},163},
4980 {{{83,7}},35}, {{{0,8}},114}, {{{0,8}},50}, {{{0,9}},197},
4981 {{{81,7}},11}, {{{0,8}},98}, {{{0,8}},34}, {{{0,9}},165},
4982 {{{0,8}},2}, {{{0,8}},130}, {{{0,8}},66}, {{{0,9}},229},
4983 {{{80,7}},7}, {{{0,8}},90}, {{{0,8}},26}, {{{0,9}},149},
4984 {{{84,7}},67}, {{{0,8}},122}, {{{0,8}},58}, {{{0,9}},213},
4985 {{{82,7}},19}, {{{0,8}},106}, {{{0,8}},42}, {{{0,9}},181},
4986 {{{0,8}},10}, {{{0,8}},138}, {{{0,8}},74}, {{{0,9}},245},
4987 {{{80,7}},5}, {{{0,8}},86}, {{{0,8}},22}, {{{192,8}},0},
4988 {{{83,7}},51}, {{{0,8}},118}, {{{0,8}},54}, {{{0,9}},205},
4989 {{{81,7}},15}, {{{0,8}},102}, {{{0,8}},38}, {{{0,9}},173},
4990 {{{0,8}},6}, {{{0,8}},134}, {{{0,8}},70}, {{{0,9}},237},
4991 {{{80,7}},9}, {{{0,8}},94}, {{{0,8}},30}, {{{0,9}},157},
4992 {{{84,7}},99}, {{{0,8}},126}, {{{0,8}},62}, {{{0,9}},221},
4993 {{{82,7}},27}, {{{0,8}},110}, {{{0,8}},46}, {{{0,9}},189},
4994 {{{0,8}},14}, {{{0,8}},142}, {{{0,8}},78}, {{{0,9}},253},
4995 {{{96,7}},256}, {{{0,8}},81}, {{{0,8}},17}, {{{85,8}},131},
4996 {{{82,7}},31}, {{{0,8}},113}, {{{0,8}},49}, {{{0,9}},195},
4997 {{{80,7}},10}, {{{0,8}},97}, {{{0,8}},33}, {{{0,9}},163},
4998 {{{0,8}},1}, {{{0,8}},129}, {{{0,8}},65}, {{{0,9}},227},
4999 {{{80,7}},6}, {{{0,8}},89}, {{{0,8}},25}, {{{0,9}},147},
5000 {{{83,7}},59}, {{{0,8}},121}, {{{0,8}},57}, {{{0,9}},211},
5001 {{{81,7}},17}, {{{0,8}},105}, {{{0,8}},41}, {{{0,9}},179},
5002 {{{0,8}},9}, {{{0,8}},137}, {{{0,8}},73}, {{{0,9}},243},
5003 {{{80,7}},4}, {{{0,8}},85}, {{{0,8}},21}, {{{80,8}},258},
5004 {{{83,7}},43}, {{{0,8}},117}, {{{0,8}},53}, {{{0,9}},203},
5005 {{{81,7}},13}, {{{0,8}},101}, {{{0,8}},37}, {{{0,9}},171},
5006 {{{0,8}},5}, {{{0,8}},133}, {{{0,8}},69}, {{{0,9}},235},
5007 {{{80,7}},8}, {{{0,8}},93}, {{{0,8}},29}, {{{0,9}},155},
5008 {{{84,7}},83}, {{{0,8}},125}, {{{0,8}},61}, {{{0,9}},219},
5009 {{{82,7}},23}, {{{0,8}},109}, {{{0,8}},45}, {{{0,9}},187},
5010 {{{0,8}},13}, {{{0,8}},141}, {{{0,8}},77}, {{{0,9}},251},
5011 {{{80,7}},3}, {{{0,8}},83}, {{{0,8}},19}, {{{85,8}},195},
5012 {{{83,7}},35}, {{{0,8}},115}, {{{0,8}},51}, {{{0,9}},199},
5013 {{{81,7}},11}, {{{0,8}},99}, {{{0,8}},35}, {{{0,9}},167},
5014 {{{0,8}},3}, {{{0,8}},131}, {{{0,8}},67}, {{{0,9}},231},
5015 {{{80,7}},7}, {{{0,8}},91}, {{{0,8}},27}, {{{0,9}},151},
5016 {{{84,7}},67}, {{{0,8}},123}, {{{0,8}},59}, {{{0,9}},215},
5017 {{{82,7}},19}, {{{0,8}},107}, {{{0,8}},43}, {{{0,9}},183},
5018 {{{0,8}},11}, {{{0,8}},139}, {{{0,8}},75}, {{{0,9}},247},
5019 {{{80,7}},5}, {{{0,8}},87}, {{{0,8}},23}, {{{192,8}},0},
5020 {{{83,7}},51}, {{{0,8}},119}, {{{0,8}},55}, {{{0,9}},207},
5021 {{{81,7}},15}, {{{0,8}},103}, {{{0,8}},39}, {{{0,9}},175},
5022 {{{0,8}},7}, {{{0,8}},135}, {{{0,8}},71}, {{{0,9}},239},
5023 {{{80,7}},9}, {{{0,8}},95}, {{{0,8}},31}, {{{0,9}},159},
5024 {{{84,7}},99}, {{{0,8}},127}, {{{0,8}},63}, {{{0,9}},223},
5025 {{{82,7}},27}, {{{0,8}},111}, {{{0,8}},47}, {{{0,9}},191},
5026 {{{0,8}},15}, {{{0,8}},143}, {{{0,8}},79}, {{{0,9}},255}
5027 };
5028 local inflate_huft fixed_td[] = {
5029 {{{80,5}},1}, {{{87,5}},257}, {{{83,5}},17}, {{{91,5}},4097},
5030 {{{81,5}},5}, {{{89,5}},1025}, {{{85,5}},65}, {{{93,5}},16385},
5031 {{{80,5}},3}, {{{88,5}},513}, {{{84,5}},33}, {{{92,5}},8193},
5032 {{{82,5}},9}, {{{90,5}},2049}, {{{86,5}},129}, {{{192,5}},24577},
5033 {{{80,5}},2}, {{{87,5}},385}, {{{83,5}},25}, {{{91,5}},6145},
5034 {{{81,5}},7}, {{{89,5}},1537}, {{{85,5}},97}, {{{93,5}},24577},
5035 {{{80,5}},4}, {{{88,5}},769}, {{{84,5}},49}, {{{92,5}},12289},
5036 {{{82,5}},13}, {{{90,5}},3073}, {{{86,5}},193}, {{{192,5}},24577}
5037 };
5038 /* --- inffixed.h */
5039
5040 #endif
5041
5042
5043 int inflate_trees_fixed(bl, bd, tl, td, z)
5044 uIntf *bl; /* literal desired/actual bit depth */
5045 uIntf *bd; /* distance desired/actual bit depth */
5046 inflate_huft * FAR *tl; /* literal/length tree result */
5047 inflate_huft * FAR *td; /* distance tree result */
5048 z_streamp z; /* for memory allocation */
5049 {
5050 #ifdef BUILDFIXED
5051 /* build fixed tables if not already */
5052 if (!fixed_built)
5053 {
5054 int k; /* temporary variable */
5055 uInt f = 0; /* number of hufts used in fixed_mem */
5056 uIntf *c; /* length list for huft_build */
5057 uIntf *v; /* work area for huft_build */
5058
5059 /* allocate memory */
5060 if ((c = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
5061 return Z_MEM_ERROR;
5062 if ((v = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
5063 {
5064 ZFREE(z, c);
5065 return Z_MEM_ERROR;
5066 }
5067
5068 /* literal table */
5069 for (k = 0; k < 144; k++)
5070 c[k] = 8;
5071 for (; k < 256; k++)
5072 c[k] = 9;
5073 for (; k < 280; k++)
5074 c[k] = 7;
5075 for (; k < 288; k++)
5076 c[k] = 8;
5077 fixed_bl = 9;
5078 huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl,
5079 fixed_mem, &f, v);
5080
5081 /* distance table */
5082 for (k = 0; k < 30; k++)
5083 c[k] = 5;
5084 fixed_bd = 5;
5085 huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd,
5086 fixed_mem, &f, v);
5087
5088 /* done */
5089 ZFREE(z, v);
5090 ZFREE(z, c);
5091 fixed_built = 1;
5092 }
5093 #endif
5094 *bl = fixed_bl;
5095 *bd = fixed_bd;
5096 *tl = fixed_tl;
5097 *td = fixed_td;
5098 return Z_OK;
5099 }
5100 /* --- inftrees.c */
5101
5102 /* +++ infcodes.c */
5103
5104 /* infcodes.c -- process literals and length/distance pairs
5105 * Copyright (C) 1995-2002 Mark Adler
5106 * For conditions of distribution and use, see copyright notice in zlib.h
5107 */
5108
5109 /* #include "zutil.h" */
5110 /* #include "inftrees.h" */
5111 /* #include "infblock.h" */
5112 /* #include "infcodes.h" */
5113 /* #include "infutil.h" */
5114
5115 /* +++ inffast.h */
5116
5117 /* inffast.h -- header to use inffast.c
5118 * Copyright (C) 1995-2002 Mark Adler
5119 * For conditions of distribution and use, see copyright notice in zlib.h
5120 */
5121
5122 /* WARNING: this file should *not* be used by applications. It is
5123 part of the implementation of the compression library and is
5124 subject to change. Applications should only use zlib.h.
5125 */
5126
5127 extern int inflate_fast __P((
5128 uInt,
5129 uInt,
5130 inflate_huft *,
5131 inflate_huft *,
5132 inflate_blocks_statef *,
5133 z_streamp ));
5134 /* --- inffast.h */
5135
5136 /* simplify the use of the inflate_huft type with some defines */
5137 #define exop word.what.Exop
5138 #define bits word.what.Bits
5139
5140 typedef enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
5141 START, /* x: set up for LEN */
5142 LEN, /* i: get length/literal/eob next */
5143 LENEXT, /* i: getting length extra (have base) */
5144 DIST, /* i: get distance next */
5145 DISTEXT, /* i: getting distance extra */
5146 COPY, /* o: copying bytes in window, waiting for space */
5147 LIT, /* o: got literal, waiting for output space */
5148 WASH, /* o: got eob, possibly still output waiting */
5149 END, /* x: got eob and all data flushed */
5150 BADCODE} /* x: got error */
5151 inflate_codes_mode;
5152
5153 /* inflate codes private state */
5154 struct inflate_codes_state {
5155
5156 /* mode */
5157 inflate_codes_mode mode; /* current inflate_codes mode */
5158
5159 /* mode dependent information */
5160 uInt len;
5161 union {
5162 struct {
5163 inflate_huft *tree; /* pointer into tree */
5164 uInt need; /* bits needed */
5165 } code; /* if LEN or DIST, where in tree */
5166 uInt lit; /* if LIT, literal */
5167 struct {
5168 uInt get; /* bits to get for extra */
5169 uInt dist; /* distance back to copy from */
5170 } copy; /* if EXT or COPY, where and how much */
5171 } sub; /* submode */
5172
5173 /* mode independent information */
5174 Byte lbits; /* ltree bits decoded per branch */
5175 Byte dbits; /* dtree bits decoder per branch */
5176 inflate_huft *ltree; /* literal/length/eob tree */
5177 inflate_huft *dtree; /* distance tree */
5178
5179 };
5180
5181
5182 inflate_codes_statef *inflate_codes_new(bl, bd, tl, td, z)
5183 uInt bl, bd;
5184 inflate_huft *tl;
5185 inflate_huft *td; /* need separate declaration for Borland C++ */
5186 z_streamp z;
5187 {
5188 inflate_codes_statef *c;
5189
5190 if ((c = (inflate_codes_statef *)
5191 ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL)
5192 {
5193 c->mode = START;
5194 c->lbits = (Byte)bl;
5195 c->dbits = (Byte)bd;
5196 c->ltree = tl;
5197 c->dtree = td;
5198 Tracev((stderr, "inflate: codes new\n"));
5199 }
5200 return c;
5201 }
5202
5203
5204 int inflate_codes(s, z, r)
5205 inflate_blocks_statef *s;
5206 z_streamp z;
5207 int r;
5208 {
5209 uInt j; /* temporary storage */
5210 inflate_huft *t; /* temporary pointer */
5211 uInt e; /* extra bits or operation */
5212 uLong b; /* bit buffer */
5213 uInt k; /* bits in bit buffer */
5214 Bytef *p; /* input data pointer */
5215 uInt n; /* bytes available there */
5216 Bytef *q; /* output window write pointer */
5217 uInt m; /* bytes to end of window or read pointer */
5218 Bytef *f; /* pointer to copy strings from */
5219 inflate_codes_statef *c = s->sub.decode.codes; /* codes state */
5220
5221 /* copy input/output information to locals (UPDATE macro restores) */
5222 LOAD
5223
5224 /* process input and output based on current state */
5225 while (1) switch (c->mode)
5226 { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
5227 case START: /* x: set up for LEN */
5228 #ifndef SLOW
5229 if (m >= 258 && n >= 10)
5230 {
5231 UPDATE
5232 r = inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z);
5233 LOAD
5234 if (r != Z_OK)
5235 {
5236 c->mode = r == Z_STREAM_END ? WASH : BADCODE;
5237 break;
5238 }
5239 }
5240 #endif /* !SLOW */
5241 c->sub.code.need = c->lbits;
5242 c->sub.code.tree = c->ltree;
5243 c->mode = LEN;
5244 case LEN: /* i: get length/literal/eob next */
5245 j = c->sub.code.need;
5246 NEEDBITS(j)
5247 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
5248 DUMPBITS(t->bits)
5249 e = (uInt)(t->exop);
5250 if (e == 0) /* literal */
5251 {
5252 c->sub.lit = t->base;
5253 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5254 "inflate: literal '%c'\n" :
5255 "inflate: literal 0x%02x\n", t->base));
5256 c->mode = LIT;
5257 break;
5258 }
5259 if (e & 16) /* length */
5260 {
5261 c->sub.copy.get = e & 15;
5262 c->len = t->base;
5263 c->mode = LENEXT;
5264 break;
5265 }
5266 if ((e & 64) == 0) /* next table */
5267 {
5268 c->sub.code.need = e;
5269 c->sub.code.tree = t + t->base;
5270 break;
5271 }
5272 if (e & 32) /* end of block */
5273 {
5274 Tracevv((stderr, "inflate: end of block\n"));
5275 c->mode = WASH;
5276 break;
5277 }
5278 c->mode = BADCODE; /* invalid code */
5279 z->msg = (char*)"invalid literal/length code";
5280 r = Z_DATA_ERROR;
5281 LEAVE
5282 case LENEXT: /* i: getting length extra (have base) */
5283 j = c->sub.copy.get;
5284 NEEDBITS(j)
5285 c->len += (uInt)b & inflate_mask[j];
5286 DUMPBITS(j)
5287 c->sub.code.need = c->dbits;
5288 c->sub.code.tree = c->dtree;
5289 Tracevv((stderr, "inflate: length %u\n", c->len));
5290 c->mode = DIST;
5291 case DIST: /* i: get distance next */
5292 j = c->sub.code.need;
5293 NEEDBITS(j)
5294 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
5295 DUMPBITS(t->bits)
5296 e = (uInt)(t->exop);
5297 if (e & 16) /* distance */
5298 {
5299 c->sub.copy.get = e & 15;
5300 c->sub.copy.dist = t->base;
5301 c->mode = DISTEXT;
5302 break;
5303 }
5304 if ((e & 64) == 0) /* next table */
5305 {
5306 c->sub.code.need = e;
5307 c->sub.code.tree = t + t->base;
5308 break;
5309 }
5310 c->mode = BADCODE; /* invalid code */
5311 z->msg = (char*)"invalid distance code";
5312 r = Z_DATA_ERROR;
5313 LEAVE
5314 case DISTEXT: /* i: getting distance extra */
5315 j = c->sub.copy.get;
5316 NEEDBITS(j)
5317 c->sub.copy.dist += (uInt)b & inflate_mask[j];
5318 DUMPBITS(j)
5319 Tracevv((stderr, "inflate: distance %u\n", c->sub.copy.dist));
5320 c->mode = COPY;
5321 case COPY: /* o: copying bytes in window, waiting for space */
5322 f = q - c->sub.copy.dist;
5323 while (f < s->window) /* modulo window size-"while" instead */
5324 f += s->end - s->window; /* of "if" handles invalid distances */
5325 while (c->len)
5326 {
5327 NEEDOUT
5328 OUTBYTE(*f++)
5329 if (f == s->end)
5330 f = s->window;
5331 c->len--;
5332 }
5333 c->mode = START;
5334 break;
5335 case LIT: /* o: got literal, waiting for output space */
5336 NEEDOUT
5337 OUTBYTE(c->sub.lit)
5338 c->mode = START;
5339 break;
5340 case WASH: /* o: got eob, possibly more output */
5341 if (k > 7) /* return unused byte, if any */
5342 {
5343 Assert(k < 16, "inflate_codes grabbed too many bytes")
5344 k -= 8;
5345 n++;
5346 p--; /* can always return one */
5347 }
5348 FLUSH
5349 if (s->read != s->write)
5350 LEAVE
5351 c->mode = END;
5352 case END:
5353 r = Z_STREAM_END;
5354 LEAVE
5355 case BADCODE: /* x: got error */
5356 r = Z_DATA_ERROR;
5357 LEAVE
5358 default:
5359 r = Z_STREAM_ERROR;
5360 LEAVE
5361 }
5362 #ifdef NEED_DUMMY_RETURN
5363 return Z_STREAM_ERROR; /* Some dumb compilers complain without this */
5364 #endif
5365 }
5366
5367
5368 void inflate_codes_free(c, z)
5369 inflate_codes_statef *c;
5370 z_streamp z;
5371 {
5372 ZFREE(z, c);
5373 Tracev((stderr, "inflate: codes free\n"));
5374 }
5375 /* --- infcodes.c */
5376
5377 /* +++ infutil.c */
5378
5379 /* inflate_util.c -- data and routines common to blocks and codes
5380 * Copyright (C) 1995-2002 Mark Adler
5381 * For conditions of distribution and use, see copyright notice in zlib.h
5382 */
5383
5384 /* #include "zutil.h" */
5385 /* #include "infblock.h" */
5386 /* #include "inftrees.h" */
5387 /* #include "infcodes.h" */
5388 /* #include "infutil.h" */
5389
5390 #ifndef NO_DUMMY_DECL
5391 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
5392 #endif
5393
5394 /* And'ing with mask[n] masks the lower n bits */
5395 uInt inflate_mask[17] = {
5396 0x0000,
5397 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
5398 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
5399 };
5400
5401
5402 /* copy as much as possible from the sliding window to the output area */
5403 int inflate_flush(s, z, r)
5404 inflate_blocks_statef *s;
5405 z_streamp z;
5406 int r;
5407 {
5408 uInt n;
5409 Bytef *p;
5410 Bytef *q;
5411
5412 /* local copies of source and destination pointers */
5413 p = z->next_out;
5414 q = s->read;
5415
5416 /* compute number of bytes to copy as far as end of window */
5417 n = (uInt)((q <= s->write ? s->write : s->end) - q);
5418 if (n > z->avail_out) n = z->avail_out;
5419 if (n && r == Z_BUF_ERROR) r = Z_OK;
5420
5421 /* update counters */
5422 z->avail_out -= n;
5423 z->total_out += n;
5424
5425 /* update check information */
5426 if (s->checkfn != Z_NULL)
5427 z->adler = s->check = (*s->checkfn)(s->check, q, n);
5428
5429 /* copy as far as end of window */
5430 if (p != Z_NULL) {
5431 zmemcpy(p, q, n);
5432 p += n;
5433 }
5434 q += n;
5435
5436 /* see if more to copy at beginning of window */
5437 if (q == s->end)
5438 {
5439 /* wrap pointers */
5440 q = s->window;
5441 if (s->write == s->end)
5442 s->write = s->window;
5443
5444 /* compute bytes to copy */
5445 n = (uInt)(s->write - q);
5446 if (n > z->avail_out) n = z->avail_out;
5447 if (n && r == Z_BUF_ERROR) r = Z_OK;
5448
5449 /* update counters */
5450 z->avail_out -= n;
5451 z->total_out += n;
5452
5453 /* update check information */
5454 if (s->checkfn != Z_NULL)
5455 z->adler = s->check = (*s->checkfn)(s->check, q, n);
5456
5457 /* copy */
5458 if (p != NULL) {
5459 zmemcpy(p, q, n);
5460 p += n;
5461 }
5462 q += n;
5463 }
5464
5465 /* update pointers */
5466 z->next_out = p;
5467 s->read = q;
5468
5469 /* done */
5470 return r;
5471 }
5472 /* --- infutil.c */
5473
5474 /* +++ inffast.c */
5475
5476 /* inffast.c -- process literals and length/distance pairs fast
5477 * Copyright (C) 1995-2002 Mark Adler
5478 * For conditions of distribution and use, see copyright notice in zlib.h
5479 */
5480
5481 /* #include "zutil.h" */
5482 /* #include "inftrees.h" */
5483 /* #include "infblock.h" */
5484 /* #include "infcodes.h" */
5485 /* #include "infutil.h" */
5486 /* #include "inffast.h" */
5487
5488 #ifndef NO_DUMMY_DECL
5489 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
5490 #endif
5491
5492 /* simplify the use of the inflate_huft type with some defines */
5493 #define exop word.what.Exop
5494 #define bits word.what.Bits
5495
5496 /* macros for bit input with no checking and for returning unused bytes */
5497 #define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}}
5498 #define UNGRAB {c=z->avail_in-n;c=(k>>3)<c?k>>3:c;n+=c;p-=c;k-=c<<3;}
5499
5500 /* Called with number of bytes left to write in window at least 258
5501 (the maximum string length) and number of input bytes available
5502 at least ten. The ten bytes are six bytes for the longest length/
5503 distance pair plus four bytes for overloading the bit buffer. */
5504
5505 int inflate_fast(bl, bd, tl, td, s, z)
5506 uInt bl, bd;
5507 inflate_huft *tl;
5508 inflate_huft *td; /* need separate declaration for Borland C++ */
5509 inflate_blocks_statef *s;
5510 z_streamp z;
5511 {
5512 inflate_huft *t; /* temporary pointer */
5513 uInt e; /* extra bits or operation */
5514 uLong b; /* bit buffer */
5515 uInt k; /* bits in bit buffer */
5516 Bytef *p; /* input data pointer */
5517 uInt n; /* bytes available there */
5518 Bytef *q; /* output window write pointer */
5519 uInt m; /* bytes to end of window or read pointer */
5520 uInt ml; /* mask for literal/length tree */
5521 uInt md; /* mask for distance tree */
5522 uInt c; /* bytes to copy */
5523 uInt d; /* distance back to copy from */
5524 Bytef *r; /* copy source pointer */
5525
5526 /* load input, output, bit values */
5527 LOAD
5528
5529 /* initialize masks */
5530 ml = inflate_mask[bl];
5531 md = inflate_mask[bd];
5532
5533 /* do until not enough input or output space for fast loop */
5534 do { /* assume called with m >= 258 && n >= 10 */
5535 /* get literal/length code */
5536 GRABBITS(20) /* max bits for literal/length code */
5537 if ((e = (t = tl + ((uInt)b & ml))->exop) == 0)
5538 {
5539 DUMPBITS(t->bits)
5540 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5541 "inflate: * literal '%c'\n" :
5542 "inflate: * literal 0x%02x\n", t->base));
5543 *q++ = (Byte)t->base;
5544 m--;
5545 continue;
5546 }
5547 do {
5548 DUMPBITS(t->bits)
5549 if (e & 16)
5550 {
5551 /* get extra bits for length */
5552 e &= 15;
5553 c = t->base + ((uInt)b & inflate_mask[e]);
5554 DUMPBITS(e)
5555 Tracevv((stderr, "inflate: * length %u\n", c));
5556
5557 /* decode distance base of block to copy */
5558 GRABBITS(15); /* max bits for distance code */
5559 e = (t = td + ((uInt)b & md))->exop;
5560 do {
5561 DUMPBITS(t->bits)
5562 if (e & 16)
5563 {
5564 /* get extra bits to add to distance base */
5565 e &= 15;
5566 GRABBITS(e) /* get extra bits (up to 13) */
5567 d = t->base + ((uInt)b & inflate_mask[e]);
5568 DUMPBITS(e)
5569 Tracevv((stderr, "inflate: * distance %u\n", d));
5570
5571 /* do the copy */
5572 m -= c;
5573 r = q - d;
5574 if (r < s->window) /* wrap if needed */
5575 {
5576 do {
5577 r += s->end - s->window; /* force pointer in window */
5578 } while (r < s->window); /* covers invalid distances */
5579 e = s->end - r;
5580 if (c > e)
5581 {
5582 c -= e; /* wrapped copy */
5583 do {
5584 *q++ = *r++;
5585 } while (--e);
5586 r = s->window;
5587 do {
5588 *q++ = *r++;
5589 } while (--c);
5590 }
5591 else /* normal copy */
5592 {
5593 *q++ = *r++; c--;
5594 *q++ = *r++; c--;
5595 do {
5596 *q++ = *r++;
5597 } while (--c);
5598 }
5599 }
5600 else /* normal copy */
5601 {
5602 *q++ = *r++; c--;
5603 *q++ = *r++; c--;
5604 do {
5605 *q++ = *r++;
5606 } while (--c);
5607 }
5608 break;
5609 }
5610 else if ((e & 64) == 0)
5611 {
5612 t += t->base;
5613 e = (t += ((uInt)b & inflate_mask[e]))->exop;
5614 }
5615 else
5616 {
5617 z->msg = (char*)"invalid distance code";
5618 UNGRAB
5619 UPDATE
5620 return Z_DATA_ERROR;
5621 }
5622 } while (1);
5623 break;
5624 }
5625 if ((e & 64) == 0)
5626 {
5627 t += t->base;
5628 if ((e = (t += ((uInt)b & inflate_mask[e]))->exop) == 0)
5629 {
5630 DUMPBITS(t->bits)
5631 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5632 "inflate: * literal '%c'\n" :
5633 "inflate: * literal 0x%02x\n", t->base));
5634 *q++ = (Byte)t->base;
5635 m--;
5636 break;
5637 }
5638 }
5639 else if (e & 32)
5640 {
5641 Tracevv((stderr, "inflate: * end of block\n"));
5642 UNGRAB
5643 UPDATE
5644 return Z_STREAM_END;
5645 }
5646 else
5647 {
5648 z->msg = (char*)"invalid literal/length code";
5649 UNGRAB
5650 UPDATE
5651 return Z_DATA_ERROR;
5652 }
5653 } while (1);
5654 } while (m >= 258 && n >= 10);
5655
5656 /* not enough input or output--restore pointers and return */
5657 UNGRAB
5658 UPDATE
5659 return Z_OK;
5660 }
5661 /* --- inffast.c */
5662
5663 /* +++ zutil.c */
5664
5665 /* zutil.c -- target dependent utility functions for the compression library
5666 * Copyright (C) 1995-2002 Jean-loup Gailly.
5667 * For conditions of distribution and use, see copyright notice in zlib.h
5668 */
5669
5670 /* @(#) Id */
5671
5672 #ifdef DEBUG_ZLIB
5673 #include <stdio.h>
5674 #endif
5675
5676 /* #include "zutil.h" */
5677
5678 #ifndef NO_DUMMY_DECL
5679 struct internal_state {int dummy;}; /* for buggy compilers */
5680 #endif
5681
5682 #ifndef STDC
5683 extern void exit __P((int));
5684 #endif
5685
5686 const char *z_errmsg[10] = {
5687 "need dictionary", /* Z_NEED_DICT 2 */
5688 "stream end", /* Z_STREAM_END 1 */
5689 "", /* Z_OK 0 */
5690 "file error", /* Z_ERRNO (-1) */
5691 "stream error", /* Z_STREAM_ERROR (-2) */
5692 "data error", /* Z_DATA_ERROR (-3) */
5693 "insufficient memory", /* Z_MEM_ERROR (-4) */
5694 "buffer error", /* Z_BUF_ERROR (-5) */
5695 "incompatible version",/* Z_VERSION_ERROR (-6) */
5696 ""};
5697
5698
5699 #if 0
5700 const char * ZEXPORT zlibVersion()
5701 {
5702 return ZLIB_VERSION;
5703 }
5704 #endif
5705
5706 #ifdef DEBUG_ZLIB
5707
5708 # ifndef verbose
5709 # define verbose 0
5710 # endif
5711 int z_verbose = verbose;
5712
5713 void z_error (m)
5714 char *m;
5715 {
5716 fprintf(stderr, "%s\n", m);
5717 exit(1);
5718 }
5719 #endif
5720
5721 /* exported to allow conversion of error code to string for compress() and
5722 * uncompress()
5723 */
5724 #if 0
5725 const char * ZEXPORT zError(err)
5726 int err;
5727 {
5728 return ERR_MSG(err);
5729 }
5730 #endif
5731
5732
5733 #ifndef HAVE_MEMCPY
5734
5735 void zmemcpy(dest, source, len)
5736 Bytef* dest;
5737 const Bytef* source;
5738 uInt len;
5739 {
5740 if (len == 0) return;
5741 do {
5742 *dest++ = *source++; /* ??? to be unrolled */
5743 } while (--len != 0);
5744 }
5745
5746 int zmemcmp(s1, s2, len)
5747 const Bytef* s1;
5748 const Bytef* s2;
5749 uInt len;
5750 {
5751 uInt j;
5752
5753 for (j = 0; j < len; j++) {
5754 if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1;
5755 }
5756 return 0;
5757 }
5758
5759 void zmemzero(dest, len)
5760 Bytef* dest;
5761 uInt len;
5762 {
5763 if (len == 0) return;
5764 do {
5765 *dest++ = 0; /* ??? to be unrolled */
5766 } while (--len != 0);
5767 }
5768 #endif
5769
5770 #ifdef __TURBOC__
5771 #if (defined( __BORLANDC__) || !defined(SMALL_MEDIUM)) && !defined(__32BIT__)
5772 /* Small and medium model in Turbo C are for now limited to near allocation
5773 * with reduced MAX_WBITS and MAX_MEM_LEVEL
5774 */
5775 # define MY_ZCALLOC
5776
5777 /* Turbo C malloc() does not allow dynamic allocation of 64K bytes
5778 * and farmalloc(64K) returns a pointer with an offset of 8, so we
5779 * must fix the pointer. Warning: the pointer must be put back to its
5780 * original form in order to free it, use zcfree().
5781 */
5782
5783 #define MAX_PTR 10
5784 /* 10*64K = 640K */
5785
5786 local int next_ptr = 0;
5787
5788 typedef struct ptr_table_s {
5789 voidpf org_ptr;
5790 voidpf new_ptr;
5791 } ptr_table;
5792
5793 local ptr_table table[MAX_PTR];
5794 /* This table is used to remember the original form of pointers
5795 * to large buffers (64K). Such pointers are normalized with a zero offset.
5796 * Since MSDOS is not a preemptive multitasking OS, this table is not
5797 * protected from concurrent access. This hack doesn't work anyway on
5798 * a protected system like OS/2. Use Microsoft C instead.
5799 */
5800
5801 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
5802 {
5803 voidpf buf = opaque; /* just to make some compilers happy */
5804 ulg bsize = (ulg)items*size;
5805
5806 /* If we allocate less than 65520 bytes, we assume that farmalloc
5807 * will return a usable pointer which doesn't have to be normalized.
5808 */
5809 if (bsize < 65520L) {
5810 buf = farmalloc(bsize);
5811 if (*(ush*)&buf != 0) return buf;
5812 } else {
5813 buf = farmalloc(bsize + 16L);
5814 }
5815 if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
5816 table[next_ptr].org_ptr = buf;
5817
5818 /* Normalize the pointer to seg:0 */
5819 *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
5820 *(ush*)&buf = 0;
5821 table[next_ptr++].new_ptr = buf;
5822 return buf;
5823 }
5824
5825 void zcfree (voidpf opaque, voidpf ptr)
5826 {
5827 int n;
5828 if (*(ush*)&ptr != 0) { /* object < 64K */
5829 farfree(ptr);
5830 return;
5831 }
5832 /* Find the original pointer */
5833 for (n = 0; n < next_ptr; n++) {
5834 if (ptr != table[n].new_ptr) continue;
5835
5836 farfree(table[n].org_ptr);
5837 while (++n < next_ptr) {
5838 table[n-1] = table[n];
5839 }
5840 next_ptr--;
5841 return;
5842 }
5843 ptr = opaque; /* just to make some compilers happy */
5844 Assert(0, "zcfree: ptr not found");
5845 }
5846 #endif
5847 #endif /* __TURBOC__ */
5848
5849
5850 #if defined(M_I86) && !defined(__32BIT__)
5851 /* Microsoft C in 16-bit mode */
5852
5853 # define MY_ZCALLOC
5854
5855 #if (!defined(_MSC_VER) || (_MSC_VER <= 600))
5856 # define _halloc halloc
5857 # define _hfree hfree
5858 #endif
5859
5860 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
5861 {
5862 if (opaque) opaque = 0; /* to make compiler happy */
5863 return _halloc((long)items, size);
5864 }
5865
5866 void zcfree (voidpf opaque, voidpf ptr)
5867 {
5868 if (opaque) opaque = 0; /* to make compiler happy */
5869 _hfree(ptr);
5870 }
5871
5872 #endif /* MSC */
5873
5874
5875 #ifndef MY_ZCALLOC /* Any system without a special alloc function */
5876
5877 #ifndef STDC
5878 extern voidp calloc __P((uInt items, uInt size));
5879 extern void free __P((voidpf ptr));
5880 #endif
5881
5882 voidpf zcalloc (opaque, items, size)
5883 voidpf opaque;
5884 unsigned items;
5885 unsigned size;
5886 {
5887 if (opaque) items += size - size; /* make compiler happy */
5888 return (voidpf)calloc(items, size);
5889 }
5890
5891 void zcfree (opaque, ptr)
5892 voidpf opaque;
5893 voidpf ptr;
5894 {
5895 free(ptr);
5896 if (opaque) return; /* make compiler happy */
5897 }
5898
5899 #endif /* MY_ZCALLOC */
5900 /* --- zutil.c */
5901
5902 /* +++ adler32.c */
5903 /* adler32.c -- compute the Adler-32 checksum of a data stream
5904 * Copyright (C) 1995-2002 Mark Adler
5905 * For conditions of distribution and use, see copyright notice in zlib.h
5906 */
5907
5908 /* @(#) $Id: zlib.c,v 1.19 2002/08/20 03:52:26 kristerw Exp $ */
5909
5910 /* #include "zlib.h" */
5911
5912 #define BASE 65521L /* largest prime smaller than 65536 */
5913 #define NMAX 5552
5914 /* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
5915
5916 #define DO1(buf,i) {s1 += buf[i]; s2 += s1;}
5917 #define DO2(buf,i) DO1(buf,i); DO1(buf,i+1);
5918 #define DO4(buf,i) DO2(buf,i); DO2(buf,i+2);
5919 #define DO8(buf,i) DO4(buf,i); DO4(buf,i+4);
5920 #define DO16(buf) DO8(buf,0); DO8(buf,8);
5921
5922 /* ========================================================================= */
5923 uLong ZEXPORT adler32(adler, buf, len)
5924 uLong adler;
5925 const Bytef *buf;
5926 uInt len;
5927 {
5928 unsigned long s1 = adler & 0xffff;
5929 unsigned long s2 = (adler >> 16) & 0xffff;
5930 int k;
5931
5932 if (buf == Z_NULL) return 1L;
5933
5934 while (len > 0) {
5935 k = len < NMAX ? len : NMAX;
5936 len -= k;
5937 while (k >= 16) {
5938 DO16(buf);
5939 buf += 16;
5940 k -= 16;
5941 }
5942 if (k != 0) do {
5943 s1 += *buf++;
5944 s2 += s1;
5945 } while (--k);
5946 s1 %= BASE;
5947 s2 %= BASE;
5948 }
5949 return (s2 << 16) | s1;
5950 }
5951 /* --- adler32.c */
5952
Cache object: ba567174d23106fcf4d6423fffce4cd6
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