1 /* $NetBSD: zlib.c,v 1.39 2024/07/04 01:10:17 rin 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 1.39 2024/07/04 01:10:17 rin 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 1.39 2024/07/04 01:10:17 rin 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 1.39 2024/07/04 01:10:17 rin 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 # include <sys/types.h>
76 # include <sys/param.h>
77 #ifdef STDC
78 # include <stddef.h>
79 # include <string.h>
80 # include <stdlib.h>
81 #endif
82 #ifdef NO_ERRNO_H
83 extern int errno;
84 #else
85 # include <errno.h>
86 #endif
87 #endif /* __NetBSD__ && _STANDALONE */
88 #endif /* __KERNEL__ */
89 #endif /* _KERNEL || KERNEL */
90
91 #ifndef local
92 # define local static
93 #endif
94 /* compile with -Dlocal if your debugger can't find static symbols */
95
96 typedef unsigned char uch;
97 typedef uch FAR uchf;
98 typedef unsigned short ush;
99 typedef ush FAR ushf;
100 typedef unsigned long ulg;
101
102 extern const char *z_errmsg[10]; /* indexed by 2-zlib_error */
103 /* (size given to avoid silly warnings with Visual C++) */
104
105 #define ERR_MSG(err) z_errmsg[Z_NEED_DICT-(err)]
106
107 #define ERR_RETURN(strm,err) \
108 return (strm->msg = ERR_MSG(err), (err))
109 /* To be used only when the state is known to be valid */
110
111 /* common constants */
112
113 #ifndef DEF_WBITS
114 # define DEF_WBITS MAX_WBITS
115 #endif
116 /* default windowBits for decompression. MAX_WBITS is for compression only */
117
118 #if MAX_MEM_LEVEL >= 8
119 # define DEF_MEM_LEVEL 8
120 #else
121 # define DEF_MEM_LEVEL MAX_MEM_LEVEL
122 #endif
123 /* default memLevel */
124
125 #define STORED_BLOCK 0
126 #define STATIC_TREES 1
127 #define DYN_TREES 2
128 /* The three kinds of block type */
129
130 #define MIN_MATCH 3
131 #define MAX_MATCH 258
132 /* The minimum and maximum match lengths */
133
134 #define PRESET_DICT 0x20 /* preset dictionary flag in zlib header */
135
136 /* target dependencies */
137
138 #ifdef MSDOS
139 # define OS_CODE 0x00
140 # if defined(__TURBOC__) || defined(__BORLANDC__)
141 # if(__STDC__ == 1) && (defined(__LARGE__) || defined(__COMPACT__))
142 /* Allow compilation with ANSI keywords only enabled */
143 void _Cdecl farfree( void *block );
144 void *_Cdecl farmalloc( unsigned long nbytes );
145 # else
146 # include <alloc.h>
147 # endif
148 # else /* MSC or DJGPP */
149 # include <malloc.h>
150 # endif
151 #endif
152
153 #ifdef OS2
154 # define OS_CODE 0x06
155 #endif
156
157 #ifdef WIN32 /* Window 95 & Windows NT */
158 # define OS_CODE 0x0b
159 #endif
160
161 #if defined(VAXC) || defined(VMS)
162 # define OS_CODE 0x02
163 # define F_OPEN(name, mode) \
164 fopen((name), (mode), "mbc=60", "ctx=stm", "rfm=fix", "mrs=512")
165 #endif
166
167 #ifdef AMIGA
168 # define OS_CODE 0x01
169 #endif
170
171 #if defined(ATARI) || defined(atarist)
172 # define OS_CODE 0x05
173 #endif
174
175 #if defined(MACOS) || defined(TARGET_OS_MAC)
176 # define OS_CODE 0x07
177 # if defined(__MWERKS__) && __dest_os != __be_os && __dest_os != __win32_os
178 # include <unix.h> /* for fdopen */
179 # else
180 # ifndef fdopen
181 # define fdopen(fd,mode) NULL /* No fdopen() */
182 # endif
183 # endif
184 #endif
185
186 #ifdef __50SERIES /* Prime/PRIMOS */
187 # define OS_CODE 0x0F
188 #endif
189
190 #ifdef TOPS20
191 # define OS_CODE 0x0a
192 #endif
193
194 #if defined(_BEOS_) || defined(RISCOS)
195 # define fdopen(fd,mode) NULL /* No fdopen() */
196 #endif
197
198 #if (defined(_MSC_VER) && (_MSC_VER > 600))
199 # define fdopen(fd,type) _fdopen(fd,type)
200 #endif
201
202
203 /* Common defaults */
204
205 #ifndef OS_CODE
206 # define OS_CODE 0x03 /* assume Unix */
207 #endif
208
209 #ifndef F_OPEN
210 # define F_OPEN(name, mode) fopen((name), (mode))
211 #endif
212
213 /* functions */
214
215 #ifdef HAVE_STRERROR
216 extern char *strerror(int);
217 # define zstrerror(errnum) strerror(errnum)
218 #else
219 # define zstrerror(errnum) ""
220 #endif
221
222 #if defined(pyr)
223 # define NO_MEMCPY
224 #endif
225 #if defined(SMALL_MEDIUM) && !defined(_MSC_VER) && !defined(__SC__)
226 /* Use our own functions for small and medium model with MSC <= 5.0.
227 * You may have to use the same strategy for Borland C (untested).
228 * The __SC__ check is for Symantec.
229 */
230 # define NO_MEMCPY
231 #endif
232 #if defined(STDC) && !defined(HAVE_MEMCPY) && !defined(NO_MEMCPY)
233 # define HAVE_MEMCPY
234 #endif
235 #ifdef HAVE_MEMCPY
236 # ifdef SMALL_MEDIUM /* MSDOS small or medium model */
237 # define zmemcpy _fmemcpy
238 # define zmemcmp _fmemcmp
239 # define zmemzero(dest, len) _fmemset(dest, 0, len)
240 # else
241 # define zmemcpy memcpy
242 # define zmemcmp memcmp
243 # define zmemzero(dest, len) memset(dest, 0, len)
244 # endif
245 #else
246 extern void zmemcpy(Bytef* dest, const Bytef* source, uInt len);
247 extern int zmemcmp(const Bytef* s1, const Bytef* s2, uInt len);
248 extern void zmemzero(Bytef* dest, uInt len);
249 #endif
250
251 /* Diagnostic functions */
252 #if defined(DEBUG_ZLIB) && !defined(_KERNEL) && !defined(_STANDALONE)
253 # include <stdio.h>
254 extern int z_verbose;
255 extern void z_error(char *m);
256 # define Assert(cond,msg) {if(!(cond)) z_error(msg);}
257 # define Trace(x) {if (z_verbose>=0) fprintf x ;}
258 # define Tracev(x) {if (z_verbose>0) fprintf x ;}
259 # define Tracevv(x) {if (z_verbose>1) fprintf x ;}
260 # define Tracec(c,x) {if (z_verbose>0 && (c)) fprintf x ;}
261 # define Tracecv(c,x) {if (z_verbose>1 && (c)) fprintf x ;}
262 #else
263 # define Assert(cond,msg)
264 # define Trace(x)
265 # define Tracev(x)
266 # define Tracevv(x)
267 # define Tracec(c,x)
268 # define Tracecv(c,x)
269 #endif
270
271
272 typedef uLong (ZEXPORT *check_func)(uLong check, const Bytef *buf,
273 uInt len);
274 voidpf zcalloc(voidpf opaque, unsigned items, unsigned size);
275 void zcfree(voidpf opaque, voidpf ptr);
276
277 #define ZALLOC(strm, items, size) \
278 (*((strm)->zalloc))((strm)->opaque, (items), (size))
279 #define ZFREE(strm, addr) (*((strm)->zfree))((strm)->opaque, (voidpf)(addr))
280 #define TRY_FREE(s, p) {if (p) ZFREE(s, p);}
281
282 #endif /* _Z_UTIL_H */
283 /* --- zutil.h */
284
285 /* +++ deflate.h */
286
287 /* deflate.h -- internal compression state
288 * Copyright (C) 1995-2002 Jean-loup Gailly
289 * For conditions of distribution and use, see copyright notice in zlib.h
290 */
291
292 /* WARNING: this file should *not* be used by applications. It is
293 part of the implementation of the compression library and is
294 subject to change. Applications should only use zlib.h.
295 */
296
297 /* @(#) $Id: zlib.c,v 1.39 2024/07/04 01:10:17 rin Exp $ */
298
299 #ifndef _DEFLATE_H
300 #define _DEFLATE_H
301
302 /* #include "zutil.h" */
303
304 /* ===========================================================================
305 * Internal compression state.
306 */
307
308 #define LENGTH_CODES 29
309 /* number of length codes, not counting the special END_BLOCK code */
310
311 #define LITERALS 256
312 /* number of literal bytes 0..255 */
313
314 #define L_CODES (LITERALS+1+LENGTH_CODES)
315 /* number of Literal or Length codes, including the END_BLOCK code */
316
317 #define D_CODES 30
318 /* number of distance codes */
319
320 #define BL_CODES 19
321 /* number of codes used to transfer the bit lengths */
322
323 #define HEAP_SIZE (2*L_CODES+1)
324 /* maximum heap size */
325
326 #define MAX_BITS 15
327 /* All codes must not exceed MAX_BITS bits */
328
329 #define INIT_STATE 42
330 #define BUSY_STATE 113
331 #define FINISH_STATE 666
332 /* Stream status */
333
334
335 /* Data structure describing a single value and its code string. */
336 typedef struct ct_data_s {
337 union {
338 ush freq; /* frequency count */
339 ush code; /* bit string */
340 } fc;
341 union {
342 ush dad; /* father node in Huffman tree */
343 ush len; /* length of bit string */
344 } dl;
345 } FAR ct_data;
346
347 #define Freq fc.freq
348 #define Code fc.code
349 #define Dad dl.dad
350 #define Len dl.len
351
352 typedef struct static_tree_desc_s static_tree_desc;
353
354 typedef struct tree_desc_s {
355 ct_data *dyn_tree; /* the dynamic tree */
356 int max_code; /* largest code with non zero frequency */
357 static_tree_desc *stat_desc; /* the corresponding static tree */
358 } FAR tree_desc;
359
360 typedef ush Pos;
361 typedef Pos FAR Posf;
362 typedef unsigned IPos;
363
364 /* A Pos is an index in the character window. We use short instead of int to
365 * save space in the various tables. IPos is used only for parameter passing.
366 */
367
368 typedef struct deflate_state {
369 z_streamp strm; /* pointer back to this zlib stream */
370 int status; /* as the name implies */
371 Bytef *pending_buf; /* output still pending */
372 ulg pending_buf_size; /* size of pending_buf */
373 Bytef *pending_out; /* next pending byte to output to the stream */
374 int pending; /* nb of bytes in the pending buffer */
375 int noheader; /* suppress zlib header and adler32 */
376 Byte data_type; /* UNKNOWN, BINARY or ASCII */
377 Byte method; /* STORED (for zip only) or DEFLATED */
378 int last_flush; /* value of flush param for previous deflate call */
379
380 /* used by deflate.c: */
381
382 uInt w_size; /* LZ77 window size (32K by default) */
383 uInt w_bits; /* log2(w_size) (8..16) */
384 uInt w_mask; /* w_size - 1 */
385
386 Bytef *window;
387 /* Sliding window. Input bytes are read into the second half of the window,
388 * and move to the first half later to keep a dictionary of at least wSize
389 * bytes. With this organization, matches are limited to a distance of
390 * wSize-MAX_MATCH bytes, but this ensures that IO is always
391 * performed with a length multiple of the block size. Also, it limits
392 * the window size to 64K, which is quite useful on MSDOS.
393 * To do: use the user input buffer as sliding window.
394 */
395
396 ulg window_size;
397 /* Actual size of window: 2*wSize, except when the user input buffer
398 * is directly used as sliding window.
399 */
400
401 Posf *prev;
402 /* Link to older string with same hash index. To limit the size of this
403 * array to 64K, this link is maintained only for the last 32K strings.
404 * An index in this array is thus a window index modulo 32K.
405 */
406
407 Posf *head; /* Heads of the hash chains or NIL. */
408
409 uInt ins_h; /* hash index of string to be inserted */
410 uInt hash_size; /* number of elements in hash table */
411 uInt hash_bits; /* log2(hash_size) */
412 uInt hash_mask; /* hash_size-1 */
413
414 uInt hash_shift;
415 /* Number of bits by which ins_h must be shifted at each input
416 * step. It must be such that after MIN_MATCH steps, the oldest
417 * byte no longer takes part in the hash key, that is:
418 * hash_shift * MIN_MATCH >= hash_bits
419 */
420
421 long block_start;
422 /* Window position at the beginning of the current output block. Gets
423 * negative when the window is moved backwards.
424 */
425
426 uInt match_length; /* length of best match */
427 IPos prev_match; /* previous match */
428 int match_available; /* set if previous match exists */
429 uInt strstart; /* start of string to insert */
430 uInt match_start; /* start of matching string */
431 uInt lookahead; /* number of valid bytes ahead in window */
432
433 uInt prev_length;
434 /* Length of the best match at previous step. Matches not greater than this
435 * are discarded. This is used in the lazy match evaluation.
436 */
437
438 uInt max_chain_length;
439 /* To speed up deflation, hash chains are never searched beyond this
440 * length. A higher limit improves compression ratio but degrades the
441 * speed.
442 */
443
444 uInt max_lazy_match;
445 /* Attempt to find a better match only when the current match is strictly
446 * smaller than this value. This mechanism is used only for compression
447 * levels >= 4.
448 */
449 # define max_insert_length max_lazy_match
450 /* Insert new strings in the hash table only if the match length is not
451 * greater than this length. This saves time but degrades compression.
452 * max_insert_length is used only for compression levels <= 3.
453 */
454
455 int level; /* compression level (1..9) */
456 int strategy; /* favor or force Huffman coding*/
457
458 uInt good_match;
459 /* Use a faster search when the previous match is longer than this */
460
461 int nice_match; /* Stop searching when current match exceeds this */
462
463 /* used by trees.c: */
464 /* Didn't use ct_data typedef below to suppress compiler warning */
465 struct ct_data_s dyn_ltree[HEAP_SIZE]; /* literal and length tree */
466 struct ct_data_s dyn_dtree[2*D_CODES+1]; /* distance tree */
467 struct ct_data_s bl_tree[2*BL_CODES+1]; /* Huffman tree for bit lengths */
468
469 struct tree_desc_s l_desc; /* desc. for literal tree */
470 struct tree_desc_s d_desc; /* desc. for distance tree */
471 struct tree_desc_s bl_desc; /* desc. for bit length tree */
472
473 ush bl_count[MAX_BITS+1];
474 /* number of codes at each bit length for an optimal tree */
475
476 int heap[2*L_CODES+1]; /* heap used to build the Huffman trees */
477 int heap_len; /* number of elements in the heap */
478 int heap_max; /* element of largest frequency */
479 /* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used.
480 * The same heap array is used to build all trees.
481 */
482
483 uch depth[2*L_CODES+1];
484 /* Depth of each subtree used as tie breaker for trees of equal frequency
485 */
486
487 uchf *l_buf; /* buffer for literals or lengths */
488
489 uInt lit_bufsize;
490 /* Size of match buffer for literals/lengths. There are 4 reasons for
491 * limiting lit_bufsize to 64K:
492 * - frequencies can be kept in 16 bit counters
493 * - if compression is not successful for the first block, all input
494 * data is still in the window so we can still emit a stored block even
495 * when input comes from standard input. (This can also be done for
496 * all blocks if lit_bufsize is not greater than 32K.)
497 * - if compression is not successful for a file smaller than 64K, we can
498 * even emit a stored file instead of a stored block (saving 5 bytes).
499 * This is applicable only for zip (not gzip or zlib).
500 * - creating new Huffman trees less frequently may not provide fast
501 * adaptation to changes in the input data statistics. (Take for
502 * example a binary file with poorly compressible code followed by
503 * a highly compressible string table.) Smaller buffer sizes give
504 * fast adaptation but have of course the overhead of transmitting
505 * trees more frequently.
506 * - I can't count above 4
507 */
508
509 uInt last_lit; /* running index in l_buf */
510
511 ushf *d_buf;
512 /* Buffer for distances. To simplify the code, d_buf and l_buf have
513 * the same number of elements. To use different lengths, an extra flag
514 * array would be necessary.
515 */
516
517 ulg opt_len; /* bit length of current block with optimal trees */
518 ulg static_len; /* bit length of current block with static trees */
519 uInt matches; /* number of string matches in current block */
520 int last_eob_len; /* bit length of EOB code for last block */
521
522 #ifdef DEBUG_ZLIB
523 ulg compressed_len; /* total bit length of compressed file mod 2^32 */
524 ulg bits_sent; /* bit length of compressed data sent mod 2^32 */
525 #endif
526
527 ush bi_buf;
528 /* Output buffer. bits are inserted starting at the bottom (least
529 * significant bits).
530 */
531 int bi_valid;
532 /* Number of valid bits in bi_buf. All bits above the last valid bit
533 * are always zero.
534 */
535
536 } FAR deflate_state;
537
538 /* Output a byte on the stream.
539 * IN assertion: there is enough room in pending_buf.
540 */
541 #define put_byte(s, c) {s->pending_buf[s->pending++] = (c);}
542
543
544 #define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
545 /* Minimum amount of lookahead, except at the end of the input file.
546 * See deflate.c for comments about the MIN_MATCH+1.
547 */
548
549 #define MAX_DIST(s) ((s)->w_size-MIN_LOOKAHEAD)
550 /* In order to simplify the code, particularly on 16 bit machines, match
551 * distances are limited to MAX_DIST instead of WSIZE.
552 */
553
554 /* in trees.c */
555 void _tr_init(deflate_state *s);
556 int _tr_tally(deflate_state *s, unsigned dist, unsigned lc);
557 void _tr_flush_block(deflate_state *s, charf *buf, ulg stored_len,
558 int eof);
559 void _tr_align(deflate_state *s);
560 void _tr_stored_block(deflate_state *s, charf *buf, ulg stored_len,
561 int eof);
562 void _tr_stored_type_only(deflate_state *);
563
564 #define d_code(dist) \
565 ((dist) < 256 ? _dist_code[dist] : _dist_code[256+((dist)>>7)])
566 /* Mapping from a distance to a distance code. dist is the distance - 1 and
567 * must not have side effects. _dist_code[256] and _dist_code[257] are never
568 * used.
569 */
570
571 #ifndef DEBUG_ZLIB
572 /* Inline versions of _tr_tally for speed: */
573
574 #if defined(GEN_TREES_H) || !defined(STDC)
575 extern uch _length_code[];
576 extern uch _dist_code[];
577 #else
578 extern const uch _length_code[];
579 extern const uch _dist_code[];
580 #endif
581
582 # define _tr_tally_lit(s, c, flush) \
583 { uch cc = (c); \
584 s->d_buf[s->last_lit] = 0; \
585 s->l_buf[s->last_lit++] = cc; \
586 s->dyn_ltree[cc].Freq++; \
587 flush = (s->last_lit == s->lit_bufsize-1); \
588 }
589 # define _tr_tally_dist(s, distance, length, flush) \
590 { uch len = (length); \
591 ush dist = (distance); \
592 s->d_buf[s->last_lit] = dist; \
593 s->l_buf[s->last_lit++] = len; \
594 dist--; \
595 s->dyn_ltree[_length_code[len]+LITERALS+1].Freq++; \
596 s->dyn_dtree[d_code(dist)].Freq++; \
597 flush = (s->last_lit == s->lit_bufsize-1); \
598 }
599 #else
600 # define _tr_tally_lit(s, c, flush) flush = _tr_tally(s, 0, c)
601 # define _tr_tally_dist(s, distance, length, flush) \
602 flush = _tr_tally(s, distance, length)
603 #endif
604
605 #endif
606 /* --- deflate.h */
607
608 /* +++ deflate.c */
609
610 /* deflate.c -- compress data using the deflation algorithm
611 * Copyright (C) 1995-2002 Jean-loup Gailly.
612 * For conditions of distribution and use, see copyright notice in zlib.h
613 */
614
615 /*
616 * ALGORITHM
617 *
618 * The "deflation" process depends on being able to identify portions
619 * of the input text which are identical to earlier input (within a
620 * sliding window trailing behind the input currently being processed).
621 *
622 * The most straightforward technique turns out to be the fastest for
623 * most input files: try all possible matches and select the longest.
624 * The key feature of this algorithm is that insertions into the string
625 * dictionary are very simple and thus fast, and deletions are avoided
626 * completely. Insertions are performed at each input character, whereas
627 * string matches are performed only when the previous match ends. So it
628 * is preferable to spend more time in matches to allow very fast string
629 * insertions and avoid deletions. The matching algorithm for small
630 * strings is inspired from that of Rabin & Karp. A brute force approach
631 * is used to find longer strings when a small match has been found.
632 * A similar algorithm is used in comic (by Jan-Mark Wams) and freeze
633 * (by Leonid Broukhis).
634 * A previous version of this file used a more sophisticated algorithm
635 * (by Fiala and Greene) which is guaranteed to run in linear amortized
636 * time, but has a larger average cost, uses more memory and is patented.
637 * However the F&G algorithm may be faster for some highly redundant
638 * files if the parameter max_chain_length (described below) is too large.
639 *
640 * ACKNOWLEDGEMENTS
641 *
642 * The idea of lazy evaluation of matches is due to Jan-Mark Wams, and
643 * I found it in 'freeze' written by Leonid Broukhis.
644 * Thanks to many people for bug reports and testing.
645 *
646 * REFERENCES
647 *
648 * Deutsch, L.P.,"DEFLATE Compressed Data Format Specification".
649 * Available in ftp://ds.internic.net/rfc/rfc1951.txt
650 *
651 * A description of the Rabin and Karp algorithm is given in the book
652 * "Algorithms" by R. Sedgewick, Addison-Wesley, p252.
653 *
654 * Fiala,E.R., and Greene,D.H.
655 * Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595
656 *
657 */
658
659 /* @(#) $Id: zlib.c,v 1.39 2024/07/04 01:10:17 rin Exp $ */
660
661 /* #include "deflate.h" */
662
663 const char deflate_copyright[] =
664 " deflate 1.1.4 Copyright 1995-2002 Jean-loup Gailly ";
665 /*
666 If you use the zlib library in a product, an acknowledgment is welcome
667 in the documentation of your product. If for some reason you cannot
668 include such an acknowledgment, I would appreciate that you keep this
669 copyright string in the executable of your product.
670 */
671
672 /* ===========================================================================
673 * Function prototypes.
674 */
675 typedef enum {
676 need_more, /* block not completed, need more input or more output */
677 block_done, /* block flush performed */
678 finish_started, /* finish started, need only more output at next deflate */
679 finish_done /* finish done, accept no more input or output */
680 } block_state;
681
682 typedef block_state (*compress_func)(deflate_state *s, int flush);
683 /* Compression function. Returns the block state after the call. */
684
685 local void fill_window(deflate_state *s);
686 local block_state deflate_stored(deflate_state *s, int flush);
687 local block_state deflate_fast(deflate_state *s, int flush);
688 local block_state deflate_slow(deflate_state *s, int flush);
689 local void lm_init(deflate_state *s);
690 local void putShortMSB(deflate_state *s, uInt b);
691 local void flush_pending(z_streamp strm);
692 local int read_buf(z_streamp strm, Bytef *buf, unsigned size);
693 #ifdef ASMV
694 void match_init(void); /* asm code initialization */
695 uInt longest_match(deflate_state *s, IPos cur_match);
696 #else
697 local uInt longest_match(deflate_state *s, IPos cur_match);
698 #endif
699
700 #ifdef DEBUG_ZLIB
701 local void check_match(deflate_state *s, IPos start, IPos match,
702 int length);
703 #endif
704
705 /* ===========================================================================
706 * Local data
707 */
708
709 #define NIL 0
710 /* Tail of hash chains */
711
712 #ifndef TOO_FAR
713 # define TOO_FAR 4096
714 #endif
715 /* Matches of length 3 are discarded if their distance exceeds TOO_FAR */
716
717 #define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
718 /* Minimum amount of lookahead, except at the end of the input file.
719 * See deflate.c for comments about the MIN_MATCH+1.
720 */
721
722 /* Values for max_lazy_match, good_match and max_chain_length, depending on
723 * the desired pack level (0..9). The values given below have been tuned to
724 * exclude worst case performance for pathological files. Better values may be
725 * found for specific files.
726 */
727 typedef struct config_s {
728 ush good_length; /* reduce lazy search above this match length */
729 ush max_lazy; /* do not perform lazy search above this match length */
730 ush nice_length; /* quit search above this match length */
731 ush max_chain;
732 compress_func func;
733 } config;
734
735 local const config configuration_table[10] = {
736 /* good lazy nice chain */
737 /* 0 */ {0, 0, 0, 0, deflate_stored}, /* store only */
738 /* 1 */ {4, 4, 8, 4, deflate_fast}, /* maximum speed, no lazy matches */
739 /* 2 */ {4, 5, 16, 8, deflate_fast},
740 /* 3 */ {4, 6, 32, 32, deflate_fast},
741
742 /* 4 */ {4, 4, 16, 16, deflate_slow}, /* lazy matches */
743 /* 5 */ {8, 16, 32, 32, deflate_slow},
744 /* 6 */ {8, 16, 128, 128, deflate_slow},
745 /* 7 */ {8, 32, 128, 256, deflate_slow},
746 /* 8 */ {32, 128, 258, 1024, deflate_slow},
747 /* 9 */ {32, 258, 258, 4096, deflate_slow}}; /* maximum compression */
748
749 /* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4
750 * For deflate_fast() (levels <= 3) good is ignored and lazy has a different
751 * meaning.
752 */
753
754 #define EQUAL 0
755 /* result of memcmp for equal strings */
756
757 #ifndef NO_DUMMY_DECL
758 struct static_tree_desc_s {int dummy;}; /* for buggy compilers */
759 #endif
760
761 /* ===========================================================================
762 * Update a hash value with the given input byte
763 * IN assertion: all calls to to UPDATE_HASH are made with consecutive
764 * input characters, so that a running hash key can be computed from the
765 * previous key instead of complete recalculation each time.
766 */
767 #define UPDATE_HASH(s,h,c) (h = (((h)<<s->hash_shift) ^ (c)) & s->hash_mask)
768
769
770 /* ===========================================================================
771 * Insert string str in the dictionary and set match_head to the previous head
772 * of the hash chain (the most recent string with same hash key). Return
773 * the previous length of the hash chain.
774 * If this file is compiled with -DFASTEST, the compression level is forced
775 * to 1, and no hash chains are maintained.
776 * IN assertion: all calls to to INSERT_STRING are made with consecutive
777 * input characters and the first MIN_MATCH bytes of str are valid
778 * (except for the last MIN_MATCH-1 bytes of the input file).
779 */
780 #ifdef FASTEST
781 #define INSERT_STRING(s, str, match_head) \
782 (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \
783 match_head = s->head[s->ins_h], \
784 s->head[s->ins_h] = (Pos)(str))
785 #else
786 #define INSERT_STRING(s, str, match_head) \
787 (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \
788 s->prev[(str) & s->w_mask] = match_head = s->head[s->ins_h], \
789 s->head[s->ins_h] = (Pos)(str))
790 #endif
791
792 /* ===========================================================================
793 * Initialize the hash table (avoiding 64K overflow for 16 bit systems).
794 * prev[] will be initialized on the fly.
795 */
796 #define CLEAR_HASH(s) \
797 s->head[s->hash_size-1] = NIL; \
798 zmemzero((Bytef *)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head));
799
800 /* ========================================================================= */
801 #if 0
802 int ZEXPORT deflateInit_(z_streamp strm,
803 int level, const char *version, int stream_size)
804 {
805 return deflateInit2_(strm, level, Z_DEFLATED, MAX_WBITS, DEF_MEM_LEVEL,
806 Z_DEFAULT_STRATEGY, version, stream_size);
807 /* To do: ignore strm->next_in if we use it as window */
808 }
809 #endif
810
811 /* ========================================================================= */
deflateInit2_(z_streamp strm,int level,int method,int windowBits,int memLevel,int strategy,const char * vers,int stream_size)812 int ZEXPORT deflateInit2_(z_streamp strm,
813 int level, int method, int windowBits, int memLevel, int strategy,
814 const char *vers, int stream_size)
815 {
816 deflate_state *s;
817 int noheader = 0;
818 static const char* my_version = ZLIB_VERSION;
819
820 ushf *overlay;
821 /* We overlay pending_buf and d_buf+l_buf. This works since the average
822 * output size for (length,distance) codes is <= 24 bits.
823 */
824
825 if (vers == Z_NULL || vers[0] != my_version[0] ||
826 stream_size != sizeof(z_stream)) {
827 return Z_VERSION_ERROR;
828 }
829 if (strm == Z_NULL) return Z_STREAM_ERROR;
830
831 strm->msg = Z_NULL;
832 #ifndef NO_ZCFUNCS
833 if (strm->zalloc == Z_NULL) {
834 strm->zalloc = zcalloc;
835 strm->opaque = (voidpf)0;
836 }
837 if (strm->zfree == Z_NULL) strm->zfree = zcfree;
838 #endif
839
840 if (level == Z_DEFAULT_COMPRESSION) level = 6;
841 #ifdef FASTEST
842 level = 1;
843 #endif
844
845 if (windowBits < 0) { /* undocumented feature: suppress zlib header */
846 noheader = 1;
847 windowBits = -windowBits;
848 }
849 if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED ||
850 windowBits < 9 || windowBits > 15 || level < 0 || level > 9 ||
851 strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
852 return Z_STREAM_ERROR;
853 }
854 s = (deflate_state *) ZALLOC(strm, 1, sizeof(deflate_state));
855 if (s == Z_NULL) return Z_MEM_ERROR;
856 strm->state = (struct internal_state FAR *)s;
857 s->strm = strm;
858
859 s->noheader = noheader;
860 s->w_bits = windowBits;
861 s->w_size = 1 << s->w_bits;
862 s->w_mask = s->w_size - 1;
863
864 s->hash_bits = memLevel + 7;
865 s->hash_size = 1 << s->hash_bits;
866 s->hash_mask = s->hash_size - 1;
867 s->hash_shift = ((s->hash_bits+MIN_MATCH-1)/MIN_MATCH);
868
869 s->window = (Bytef *) ZALLOC(strm, s->w_size, 2*sizeof(Byte));
870 s->prev = (Posf *) ZALLOC(strm, s->w_size, sizeof(Pos));
871 s->head = (Posf *) ZALLOC(strm, s->hash_size, sizeof(Pos));
872
873 s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */
874
875 overlay = (ushf *) ZALLOC(strm, s->lit_bufsize, sizeof(ush)+2);
876 s->pending_buf = (uchf *) overlay;
877 s->pending_buf_size = (ulg)s->lit_bufsize * (sizeof(ush)+2L);
878
879 if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL ||
880 s->pending_buf == Z_NULL) {
881 strm->msg = ERR_MSG(Z_MEM_ERROR);
882 s->status = INIT_STATE;
883 deflateEnd (strm);
884 return Z_MEM_ERROR;
885 }
886 s->d_buf = overlay + s->lit_bufsize/sizeof(ush);
887 s->l_buf = s->pending_buf + (1+sizeof(ush))*s->lit_bufsize;
888
889 s->level = level;
890 s->strategy = strategy;
891 s->method = (Byte)method;
892
893 return deflateReset(strm);
894 }
895
896 /* ========================================================================= */
897 #if 0
898 int ZEXPORT deflateSetDictionary (z_streamp strm,
899 const Bytef *dictionary,
900 uInt dictLength)
901 {
902 deflate_state *s;
903 uInt length = dictLength;
904 uInt n;
905 IPos hash_head = 0;
906
907 if (strm == Z_NULL || strm->state == Z_NULL || dictionary == Z_NULL)
908 return Z_STREAM_ERROR;
909
910 s = (deflate_state *)strm->state;
911 if (s->status != INIT_STATE) return Z_STREAM_ERROR;
912
913 strm->adler = adler32(strm->adler, dictionary, dictLength);
914
915 if (length < MIN_MATCH) return Z_OK;
916 if (length > MAX_DIST(s)) {
917 length = MAX_DIST(s);
918 #ifndef USE_DICT_HEAD
919 dictionary += dictLength - length; /* use the tail of the dictionary */
920 #endif
921 }
922 zmemcpy(s->window, dictionary, length);
923 s->strstart = length;
924 s->block_start = (long)length;
925
926 /* Insert all strings in the hash table (except for the last two bytes).
927 * s->lookahead stays null, so s->ins_h will be recomputed at the next
928 * call of fill_window.
929 */
930 s->ins_h = s->window[0];
931 UPDATE_HASH(s, s->ins_h, s->window[1]);
932 for (n = 0; n <= length - MIN_MATCH; n++) {
933 INSERT_STRING(s, n, hash_head);
934 }
935 if (hash_head) hash_head = 0; /* to make compiler happy */
936 return Z_OK;
937 }
938 #endif
939
940 /* ========================================================================= */
deflateReset(z_streamp strm)941 int ZEXPORT deflateReset (z_streamp strm)
942 {
943 deflate_state *s;
944
945 if (strm == Z_NULL || strm->state == Z_NULL ||
946 strm->zalloc == Z_NULL || strm->zfree == Z_NULL) return Z_STREAM_ERROR;
947
948 strm->total_in = strm->total_out = 0;
949 strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */
950 strm->data_type = Z_UNKNOWN;
951
952 s = (deflate_state *)strm->state;
953 s->pending = 0;
954 s->pending_out = s->pending_buf;
955
956 if (s->noheader < 0) {
957 s->noheader = 0; /* was set to -1 by deflate(..., Z_FINISH); */
958 }
959 s->status = s->noheader ? BUSY_STATE : INIT_STATE;
960 strm->adler = 1;
961 s->last_flush = Z_NO_FLUSH;
962
963 _tr_init(s);
964 lm_init(s);
965
966 return Z_OK;
967 }
968
969 /* ========================================================================= */
970 #if 0
971 int ZEXPORT deflateParams(strm, level, strategy)
972 z_streamp strm;
973 int level;
974 int strategy;
975 {
976 deflate_state *s;
977 compress_func func;
978 int err = Z_OK;
979
980 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
981 s = (deflate_state *)strm->state;
982
983 if (level == Z_DEFAULT_COMPRESSION) {
984 level = 6;
985 }
986 if (level < 0 || level > 9 || strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
987 return Z_STREAM_ERROR;
988 }
989 func = configuration_table[s->level].func;
990
991 if (func != configuration_table[level].func && strm->total_in != 0) {
992 /* Flush the last buffer: */
993 err = deflate(strm, Z_PARTIAL_FLUSH);
994 }
995 if (s->level != level) {
996 s->level = level;
997 s->max_lazy_match = configuration_table[level].max_lazy;
998 s->good_match = configuration_table[level].good_length;
999 s->nice_match = configuration_table[level].nice_length;
1000 s->max_chain_length = configuration_table[level].max_chain;
1001 }
1002 s->strategy = strategy;
1003 return err;
1004 }
1005 #endif
1006
1007 /* =========================================================================
1008 * Put a short in the pending buffer. The 16-bit value is put in MSB order.
1009 * IN assertion: the stream state is correct and there is enough room in
1010 * pending_buf.
1011 */
putShortMSB(deflate_state * s,uInt b)1012 local void putShortMSB (deflate_state *s, uInt b)
1013 {
1014 put_byte(s, (Byte)(b >> 8));
1015 put_byte(s, (Byte)(b & 0xff));
1016 }
1017
1018 /* =========================================================================
1019 * Flush as much pending output as possible. All deflate() output goes
1020 * through this function so some applications may wish to modify it
1021 * to avoid allocating a large strm->next_out buffer and copying into it.
1022 * (See also read_buf()).
1023 */
flush_pending(z_streamp strm)1024 local void flush_pending(z_streamp strm)
1025 {
1026 deflate_state *s = (deflate_state *) strm->state;
1027 unsigned len = s->pending;
1028
1029 if (len > strm->avail_out) len = strm->avail_out;
1030 if (len == 0) return;
1031
1032 if (strm->next_out != Z_NULL) {
1033 zmemcpy(strm->next_out, s->pending_out, len);
1034 strm->next_out += len;
1035 }
1036 s->pending_out += len;
1037 strm->total_out += len;
1038 strm->avail_out -= len;
1039 s->pending -= len;
1040 if (s->pending == 0) {
1041 s->pending_out = s->pending_buf;
1042 }
1043 }
1044
1045 /* ========================================================================= */
deflate(z_streamp strm,int flush)1046 int ZEXPORT deflate (z_streamp strm, int flush)
1047 {
1048 int old_flush; /* value of flush param for previous deflate call */
1049 deflate_state *s;
1050
1051 if (strm == Z_NULL || strm->state == Z_NULL ||
1052 flush > Z_FINISH || flush < 0) {
1053 return Z_STREAM_ERROR;
1054 }
1055 s = (deflate_state *)strm->state;
1056
1057 if ((strm->next_in == Z_NULL && strm->avail_in != 0) ||
1058 (s->status == FINISH_STATE && flush != Z_FINISH)) {
1059 ERR_RETURN(strm, Z_STREAM_ERROR);
1060 }
1061 if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR);
1062
1063 s->strm = strm; /* just in case */
1064 old_flush = s->last_flush;
1065 s->last_flush = flush;
1066
1067 /* Write the zlib header */
1068 if (s->status == INIT_STATE) {
1069
1070 uInt header = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8;
1071 uInt level_flags = (s->level-1) >> 1;
1072
1073 if (level_flags > 3) level_flags = 3;
1074 header |= (level_flags << 6);
1075 if (s->strstart != 0) header |= PRESET_DICT;
1076 header += 31 - (header % 31);
1077
1078 s->status = BUSY_STATE;
1079 putShortMSB(s, header);
1080
1081 /* Save the adler32 of the preset dictionary: */
1082 if (s->strstart != 0) {
1083 putShortMSB(s, (uInt)(strm->adler >> 16));
1084 putShortMSB(s, (uInt)(strm->adler & 0xffff));
1085 }
1086 strm->adler = 1L;
1087 }
1088
1089 /* Flush as much pending output as possible */
1090 if (s->pending != 0) {
1091 flush_pending(strm);
1092 if (strm->avail_out == 0) {
1093 /* Since avail_out is 0, deflate will be called again with
1094 * more output space, but possibly with both pending and
1095 * avail_in equal to zero. There won't be anything to do,
1096 * but this is not an error situation so make sure we
1097 * return OK instead of BUF_ERROR at next call of deflate:
1098 */
1099 s->last_flush = -1;
1100 return Z_OK;
1101 }
1102
1103 /* Make sure there is something to do and avoid duplicate consecutive
1104 * flushes. For repeated and useless calls with Z_FINISH, we keep
1105 * returning Z_STREAM_END instead of Z_BUFF_ERROR.
1106 */
1107 } else if (strm->avail_in == 0 && flush <= old_flush &&
1108 flush != Z_FINISH) {
1109 ERR_RETURN(strm, Z_BUF_ERROR);
1110 }
1111
1112 /* User must not provide more input after the first FINISH: */
1113 if (s->status == FINISH_STATE && strm->avail_in != 0) {
1114 ERR_RETURN(strm, Z_BUF_ERROR);
1115 }
1116
1117 /* Start a new block or continue the current one.
1118 */
1119 if (strm->avail_in != 0 || s->lookahead != 0 ||
1120 (flush != Z_NO_FLUSH && s->status != FINISH_STATE)) {
1121 block_state bstate;
1122
1123 bstate = (*(configuration_table[s->level].func))(s, flush);
1124
1125 if (bstate == finish_started || bstate == finish_done) {
1126 s->status = FINISH_STATE;
1127 }
1128 if (bstate == need_more || bstate == finish_started) {
1129 if (strm->avail_out == 0) {
1130 s->last_flush = -1; /* avoid BUF_ERROR next call, see above */
1131 }
1132 return Z_OK;
1133 /* If flush != Z_NO_FLUSH && avail_out == 0, the next call
1134 * of deflate should use the same flush parameter to make sure
1135 * that the flush is complete. So we don't have to output an
1136 * empty block here, this will be done at next call. This also
1137 * ensures that for a very small output buffer, we emit at most
1138 * one empty block.
1139 */
1140 }
1141 if (bstate == block_done) {
1142 if (flush == Z_PARTIAL_FLUSH) {
1143 _tr_align(s);
1144 } else if (flush == Z_PACKET_FLUSH) {
1145 /* Output just the 3-bit `stored' block type value,
1146 but not a zero length. */
1147 _tr_stored_type_only(s);
1148 } else { /* FULL_FLUSH or SYNC_FLUSH */
1149 _tr_stored_block(s, (char*)0, 0L, 0);
1150 /* For a full flush, this empty block will be recognized
1151 * as a special marker by inflate_sync().
1152 */
1153 if (flush == Z_FULL_FLUSH) {
1154 CLEAR_HASH(s); /* forget history */
1155 }
1156 }
1157 flush_pending(strm);
1158 if (strm->avail_out == 0) {
1159 s->last_flush = -1; /* avoid BUF_ERROR at next call, see above */
1160 return Z_OK;
1161 }
1162 }
1163 }
1164 Assert(strm->avail_out > 0, "bug2");
1165
1166 if (flush != Z_FINISH) return Z_OK;
1167 if (s->noheader) return Z_STREAM_END;
1168
1169 /* Write the zlib trailer (adler32) */
1170 putShortMSB(s, (uInt)(strm->adler >> 16));
1171 putShortMSB(s, (uInt)(strm->adler & 0xffff));
1172 flush_pending(strm);
1173 /* If avail_out is zero, the application will call deflate again
1174 * to flush the rest.
1175 */
1176 s->noheader = -1; /* write the trailer only once! */
1177 return s->pending != 0 ? Z_OK : Z_STREAM_END;
1178 }
1179
1180 /* ========================================================================= */
deflateEnd(z_streamp strm)1181 int ZEXPORT deflateEnd (z_streamp strm)
1182 {
1183 int status;
1184 deflate_state *s;
1185
1186 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
1187 s = (deflate_state *) strm->state;
1188
1189 status = s->status;
1190 if (status != INIT_STATE && status != BUSY_STATE &&
1191 status != FINISH_STATE) {
1192 return Z_STREAM_ERROR;
1193 }
1194
1195 /* Deallocate in reverse order of allocations: */
1196 TRY_FREE(strm, s->pending_buf);
1197 TRY_FREE(strm, s->head);
1198 TRY_FREE(strm, s->prev);
1199 TRY_FREE(strm, s->window);
1200
1201 ZFREE(strm, s);
1202 strm->state = Z_NULL;
1203
1204 return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK;
1205 }
1206
1207 /* =========================================================================
1208 * Copy the source state to the destination state.
1209 * To simplify the source, this is not supported for 16-bit MSDOS (which
1210 * doesn't have enough memory anyway to duplicate compression states).
1211 */
1212 #if 0
1213 int ZEXPORT deflateCopy (z_streamp dest, z_streamp source)
1214 {
1215 #ifdef MAXSEG_64K
1216 return Z_STREAM_ERROR;
1217 #else
1218 deflate_state *ds;
1219 deflate_state *ss;
1220 ushf *overlay;
1221
1222
1223 if (source == Z_NULL || dest == Z_NULL || source->state == Z_NULL) {
1224 return Z_STREAM_ERROR;
1225 }
1226
1227 ss = (deflate_state *)source->state;
1228
1229 *dest = *source;
1230
1231 ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state));
1232 if (ds == Z_NULL) return Z_MEM_ERROR;
1233 dest->state = (void *) ds;
1234 *ds = *ss;
1235 ds->strm = dest;
1236
1237 ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte));
1238 ds->prev = (Posf *) ZALLOC(dest, ds->w_size, sizeof(Pos));
1239 ds->head = (Posf *) ZALLOC(dest, ds->hash_size, sizeof(Pos));
1240 overlay = (ushf *) ZALLOC(dest, ds->lit_bufsize, sizeof(ush)+2);
1241 ds->pending_buf = (uchf *) overlay;
1242
1243 if (ds->window == Z_NULL || ds->prev == Z_NULL || ds->head == Z_NULL ||
1244 ds->pending_buf == Z_NULL) {
1245 ds->status = INIT_STATE;
1246 deflateEnd (dest);
1247 return Z_MEM_ERROR;
1248 }
1249 /* following zmemcpy do not work for 16-bit MSDOS */
1250 zmemcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte));
1251 zmemcpy(ds->prev, ss->prev, ds->w_size * sizeof(Pos));
1252 zmemcpy(ds->head, ss->head, ds->hash_size * sizeof(Pos));
1253 zmemcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size);
1254
1255 ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf);
1256 ds->d_buf = overlay + ds->lit_bufsize/sizeof(ush);
1257 ds->l_buf = ds->pending_buf + (1+sizeof(ush))*ds->lit_bufsize;
1258
1259 ds->l_desc.dyn_tree = ds->dyn_ltree;
1260 ds->d_desc.dyn_tree = ds->dyn_dtree;
1261 ds->bl_desc.dyn_tree = ds->bl_tree;
1262
1263 return Z_OK;
1264 #endif
1265 }
1266 #endif
1267
1268 /* ===========================================================================
1269 * Return the number of bytes of output which are immediately available
1270 * for output from the decompressor.
1271 */
1272 #if 0
1273 int deflateOutputPending (z_streamp strm)
1274 {
1275 if (strm == Z_NULL || strm->state == Z_NULL) return 0;
1276
1277 return ((deflate_state *)(strm->state))->pending;
1278 }
1279 #endif
1280
1281 /* ===========================================================================
1282 * Read a new buffer from the current input stream, update the adler32
1283 * and total number of bytes read. All deflate() input goes through
1284 * this function so some applications may wish to modify it to avoid
1285 * allocating a large strm->next_in buffer and copying from it.
1286 * (See also flush_pending()).
1287 */
read_buf(z_streamp strm,Bytef * buf,unsigned size)1288 local int read_buf(z_streamp strm,
1289 Bytef *buf,
1290 unsigned size)
1291 {
1292 unsigned len = strm->avail_in;
1293
1294 if (len > size) len = size;
1295 if (len == 0) return 0;
1296
1297 strm->avail_in -= len;
1298
1299 if (!((deflate_state *)(strm->state))->noheader) {
1300 strm->adler = adler32(strm->adler, strm->next_in, len);
1301 }
1302 zmemcpy(buf, strm->next_in, len);
1303 strm->next_in += len;
1304 strm->total_in += len;
1305
1306 return (int)len;
1307 }
1308
1309 /* ===========================================================================
1310 * Initialize the "longest match" routines for a new zlib stream
1311 */
lm_init(deflate_state * s)1312 local void lm_init (deflate_state *s)
1313 {
1314 s->window_size = (ulg)2L*s->w_size;
1315
1316 CLEAR_HASH(s);
1317
1318 /* Set the default configuration parameters:
1319 */
1320 s->max_lazy_match = configuration_table[s->level].max_lazy;
1321 s->good_match = configuration_table[s->level].good_length;
1322 s->nice_match = configuration_table[s->level].nice_length;
1323 s->max_chain_length = configuration_table[s->level].max_chain;
1324
1325 s->strstart = 0;
1326 s->block_start = 0L;
1327 s->lookahead = 0;
1328 s->match_length = s->prev_length = MIN_MATCH-1;
1329 s->match_available = 0;
1330 s->ins_h = 0;
1331 #ifdef ASMV
1332 match_init(); /* initialize the asm code */
1333 #endif
1334 }
1335
1336 /* ===========================================================================
1337 * Set match_start to the longest match starting at the given string and
1338 * return its length. Matches shorter or equal to prev_length are discarded,
1339 * in which case the result is equal to prev_length and match_start is
1340 * garbage.
1341 * IN assertions: cur_match is the head of the hash chain for the current
1342 * string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1
1343 * OUT assertion: the match length is not greater than s->lookahead.
1344 */
1345 #ifndef ASMV
1346 /* For 80x86 and 680x0, an optimized version will be provided in match.asm or
1347 * match.S. The code will be functionally equivalent.
1348 */
1349 #ifndef FASTEST
longest_match(deflate_state * s,IPos cur_match)1350 local uInt longest_match(deflate_state *s,
1351 IPos cur_match) /* current match */
1352 {
1353 unsigned chain_length = s->max_chain_length;/* max hash chain length */
1354 Bytef *scan = s->window + s->strstart; /* current string */
1355 Bytef *match; /* matched string */
1356 int len; /* length of current match */
1357 int best_len = s->prev_length; /* best match length so far */
1358 int nice_match = s->nice_match; /* stop if match long enough */
1359 IPos limit = s->strstart > (IPos)MAX_DIST(s) ?
1360 s->strstart - (IPos)MAX_DIST(s) : NIL;
1361 /* Stop when cur_match becomes <= limit. To simplify the code,
1362 * we prevent matches with the string of window index 0.
1363 */
1364 Posf *prev = s->prev;
1365 uInt wmask = s->w_mask;
1366
1367 #ifdef UNALIGNED_OK
1368 /* Compare two bytes at a time. Note: this is not always beneficial.
1369 * Try with and without -DUNALIGNED_OK to check.
1370 */
1371 Bytef *strend = s->window + s->strstart + MAX_MATCH - 1;
1372 ush scan_start = *(ushf*)scan;
1373 ush scan_end = *(ushf*)(scan+best_len-1);
1374 #else
1375 Bytef *strend = s->window + s->strstart + MAX_MATCH;
1376 Byte scan_end1 = scan[best_len-1];
1377 Byte scan_end = scan[best_len];
1378 #endif
1379
1380 /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
1381 * It is easy to get rid of this optimization if necessary.
1382 */
1383 Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");
1384
1385 /* Do not waste too much time if we already have a good match: */
1386 if (s->prev_length >= s->good_match) {
1387 chain_length >>= 2;
1388 }
1389 /* Do not look for matches beyond the end of the input. This is necessary
1390 * to make deflate deterministic.
1391 */
1392 if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;
1393
1394 Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
1395
1396 do {
1397 Assert(cur_match < s->strstart, "no future");
1398 match = s->window + cur_match;
1399
1400 /* Skip to next match if the match length cannot increase
1401 * or if the match length is less than 2:
1402 */
1403 #if (defined(UNALIGNED_OK) && MAX_MATCH == 258)
1404 /* This code assumes sizeof(unsigned short) == 2. Do not use
1405 * UNALIGNED_OK if your compiler uses a different size.
1406 */
1407 if (*(ushf*)(match+best_len-1) != scan_end ||
1408 *(ushf*)match != scan_start) continue;
1409
1410 /* It is not necessary to compare scan[2] and match[2] since they are
1411 * always equal when the other bytes match, given that the hash keys
1412 * are equal and that HASH_BITS >= 8. Compare 2 bytes at a time at
1413 * strstart+3, +5, ... up to strstart+257. We check for insufficient
1414 * lookahead only every 4th comparison; the 128th check will be made
1415 * at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is
1416 * necessary to put more guard bytes at the end of the window, or
1417 * to check more often for insufficient lookahead.
1418 */
1419 Assert(scan[2] == match[2], "scan[2]?");
1420 scan++, match++;
1421 do {
1422 } while (*(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1423 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1424 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1425 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1426 scan < strend);
1427 /* The funny "do {}" generates better code on most compilers */
1428
1429 /* Here, scan <= window+strstart+257 */
1430 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1431 if (*scan == *match) scan++;
1432
1433 len = (MAX_MATCH - 1) - (int)(strend-scan);
1434 scan = strend - (MAX_MATCH-1);
1435
1436 #else /* UNALIGNED_OK */
1437
1438 if (match[best_len] != scan_end ||
1439 match[best_len-1] != scan_end1 ||
1440 *match != *scan ||
1441 *++match != scan[1]) continue;
1442
1443 /* The check at best_len-1 can be removed because it will be made
1444 * again later. (This heuristic is not always a win.)
1445 * It is not necessary to compare scan[2] and match[2] since they
1446 * are always equal when the other bytes match, given that
1447 * the hash keys are equal and that HASH_BITS >= 8.
1448 */
1449 scan += 2, match++;
1450 Assert(*scan == *match, "match[2]?");
1451
1452 /* We check for insufficient lookahead only every 8th comparison;
1453 * the 256th check will be made at strstart+258.
1454 */
1455 do {
1456 } while (*++scan == *++match && *++scan == *++match &&
1457 *++scan == *++match && *++scan == *++match &&
1458 *++scan == *++match && *++scan == *++match &&
1459 *++scan == *++match && *++scan == *++match &&
1460 scan < strend);
1461
1462 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1463
1464 len = MAX_MATCH - (int)(strend - scan);
1465 scan = strend - MAX_MATCH;
1466
1467 #endif /* UNALIGNED_OK */
1468
1469 if (len > best_len) {
1470 s->match_start = cur_match;
1471 best_len = len;
1472 if (len >= nice_match) break;
1473 #ifdef UNALIGNED_OK
1474 scan_end = *(ushf*)(scan+best_len-1);
1475 #else
1476 scan_end1 = scan[best_len-1];
1477 scan_end = scan[best_len];
1478 #endif
1479 }
1480 } while ((cur_match = prev[cur_match & wmask]) > limit
1481 && --chain_length != 0);
1482
1483 if ((uInt)best_len <= s->lookahead) return (uInt)best_len;
1484 return s->lookahead;
1485 }
1486
1487 #else /* FASTEST */
1488 /* ---------------------------------------------------------------------------
1489 * Optimized version for level == 1 only
1490 */
longest_match(s,cur_match)1491 local uInt longest_match(s, cur_match)
1492 deflate_state *s;
1493 IPos cur_match; /* current match */
1494 {
1495 register Bytef *scan = s->window + s->strstart; /* current string */
1496 register Bytef *match; /* matched string */
1497 register int len; /* length of current match */
1498 register Bytef *strend = s->window + s->strstart + MAX_MATCH;
1499
1500 /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
1501 * It is easy to get rid of this optimization if necessary.
1502 */
1503 Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");
1504
1505 Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
1506
1507 Assert(cur_match < s->strstart, "no future");
1508
1509 match = s->window + cur_match;
1510
1511 /* Return failure if the match length is less than 2:
1512 */
1513 if (match[0] != scan[0] || match[1] != scan[1]) return MIN_MATCH-1;
1514
1515 /* The check at best_len-1 can be removed because it will be made
1516 * again later. (This heuristic is not always a win.)
1517 * It is not necessary to compare scan[2] and match[2] since they
1518 * are always equal when the other bytes match, given that
1519 * the hash keys are equal and that HASH_BITS >= 8.
1520 */
1521 scan += 2, match += 2;
1522 Assert(*scan == *match, "match[2]?");
1523
1524 /* We check for insufficient lookahead only every 8th comparison;
1525 * the 256th check will be made at strstart+258.
1526 */
1527 do {
1528 } while (*++scan == *++match && *++scan == *++match &&
1529 *++scan == *++match && *++scan == *++match &&
1530 *++scan == *++match && *++scan == *++match &&
1531 *++scan == *++match && *++scan == *++match &&
1532 scan < strend);
1533
1534 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1535
1536 len = MAX_MATCH - (int)(strend - scan);
1537
1538 if (len < MIN_MATCH) return MIN_MATCH - 1;
1539
1540 s->match_start = cur_match;
1541 return len <= s->lookahead ? len : s->lookahead;
1542 }
1543 #endif /* FASTEST */
1544 #endif /* ASMV */
1545
1546 #ifdef DEBUG_ZLIB
1547 /* ===========================================================================
1548 * Check that the match at match_start is indeed a match.
1549 */
check_match(s,start,match,length)1550 local void check_match(s, start, match, length)
1551 deflate_state *s;
1552 IPos start, match;
1553 int length;
1554 {
1555 /* check that the match is indeed a match */
1556 if (zmemcmp(s->window + match,
1557 s->window + start, length) != EQUAL) {
1558 fprintf(stderr, " start %u, match %u, length %d\n",
1559 start, match, length);
1560 do {
1561 fprintf(stderr, "%c%c", s->window[match++], s->window[start++]);
1562 } while (--length != 0);
1563 z_error("invalid match");
1564 }
1565 if (z_verbose > 1) {
1566 fprintf(stderr,"\\[%d,%d]", start-match, length);
1567 do { putc(s->window[start++], stderr); } while (--length != 0);
1568 }
1569 }
1570 #else
1571 # define check_match(s, start, match, length)
1572 #endif
1573
1574 /* ===========================================================================
1575 * Fill the window when the lookahead becomes insufficient.
1576 * Updates strstart and lookahead.
1577 *
1578 * IN assertion: lookahead < MIN_LOOKAHEAD
1579 * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD
1580 * At least one byte has been read, or avail_in == 0; reads are
1581 * performed for at least two bytes (required for the zip translate_eol
1582 * option -- not supported here).
1583 */
fill_window(deflate_state * s)1584 local void fill_window(deflate_state *s)
1585 {
1586 unsigned n, m;
1587 Posf *p;
1588 unsigned more; /* Amount of free space at the end of the window. */
1589 uInt wsize = s->w_size;
1590
1591 do {
1592 more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart);
1593
1594 /* Deal with !@#$% 64K limit: */
1595 if (more == 0 && s->strstart == 0 && s->lookahead == 0) {
1596 more = wsize;
1597
1598 } else if (more == (unsigned)(-1)) {
1599 /* Very unlikely, but possible on 16 bit machine if strstart == 0
1600 * and lookahead == 1 (input done one byte at time)
1601 */
1602 more--;
1603
1604 /* If the window is almost full and there is insufficient lookahead,
1605 * move the upper half to the lower one to make room in the upper half.
1606 */
1607 } else if (s->strstart >= wsize+MAX_DIST(s)) {
1608
1609 zmemcpy(s->window, s->window+wsize, (unsigned)wsize);
1610 s->match_start -= wsize;
1611 s->strstart -= wsize; /* we now have strstart >= MAX_DIST */
1612 s->block_start -= (long) wsize;
1613
1614 /* Slide the hash table (could be avoided with 32 bit values
1615 at the expense of memory usage). We slide even when level == 0
1616 to keep the hash table consistent if we switch back to level > 0
1617 later. (Using level 0 permanently is not an optimal usage of
1618 zlib, so we don't care about this pathological case.)
1619 */
1620 n = s->hash_size;
1621 p = &s->head[n];
1622 do {
1623 m = *--p;
1624 *p = (Pos)(m >= wsize ? m-wsize : NIL);
1625 } while (--n);
1626
1627 n = wsize;
1628 #ifndef FASTEST
1629 p = &s->prev[n];
1630 do {
1631 m = *--p;
1632 *p = (Pos)(m >= wsize ? m-wsize : NIL);
1633 /* If n is not on any hash chain, prev[n] is garbage but
1634 * its value will never be used.
1635 */
1636 } while (--n);
1637 #endif
1638 more += wsize;
1639 }
1640 if (s->strm->avail_in == 0) return;
1641
1642 /* If there was no sliding:
1643 * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 &&
1644 * more == window_size - lookahead - strstart
1645 * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1)
1646 * => more >= window_size - 2*WSIZE + 2
1647 * In the BIG_MEM or MMAP case (not yet supported),
1648 * window_size == input_size + MIN_LOOKAHEAD &&
1649 * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD.
1650 * Otherwise, window_size == 2*WSIZE so more >= 2.
1651 * If there was sliding, more >= WSIZE. So in all cases, more >= 2.
1652 */
1653 Assert(more >= 2, "more < 2");
1654
1655 n = read_buf(s->strm, s->window + s->strstart + s->lookahead, more);
1656 s->lookahead += n;
1657
1658 /* Initialize the hash value now that we have some input: */
1659 if (s->lookahead >= MIN_MATCH) {
1660 s->ins_h = s->window[s->strstart];
1661 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
1662 #if MIN_MATCH != 3
1663 Call UPDATE_HASH() MIN_MATCH-3 more times
1664 #endif
1665 }
1666 /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage,
1667 * but this is not important since only literal bytes will be emitted.
1668 */
1669
1670 } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0);
1671 }
1672
1673 /* ===========================================================================
1674 * Flush the current block, with given end-of-file flag.
1675 * IN assertion: strstart is set to the end of the current match.
1676 */
1677 #define FLUSH_BLOCK_ONLY(s, eof) { \
1678 _tr_flush_block(s, (s->block_start >= 0L ? \
1679 (charf *)&s->window[(unsigned)s->block_start] : \
1680 (charf *)Z_NULL), \
1681 (ulg)((long)s->strstart - s->block_start), \
1682 (eof)); \
1683 s->block_start = s->strstart; \
1684 flush_pending(s->strm); \
1685 Tracev((stderr,"[FLUSH]")); \
1686 }
1687
1688 /* Same but force premature exit if necessary. */
1689 #define FLUSH_BLOCK(s, eof) { \
1690 FLUSH_BLOCK_ONLY(s, eof); \
1691 if (s->strm->avail_out == 0) return (eof) ? finish_started : need_more; \
1692 }
1693
1694 /* ===========================================================================
1695 * Copy without compression as much as possible from the input stream, return
1696 * the current block state.
1697 * This function does not insert new strings in the dictionary since
1698 * uncompressible data is probably not useful. This function is used
1699 * only for the level=0 compression option.
1700 * NOTE: this function should be optimized to avoid extra copying from
1701 * window to pending_buf.
1702 */
deflate_stored(deflate_state * s,int flush)1703 local block_state deflate_stored(deflate_state *s, int flush)
1704 {
1705 /* Stored blocks are limited to 0xffff bytes, pending_buf is limited
1706 * to pending_buf_size, and each stored block has a 5 byte header:
1707 */
1708 ulg max_block_size = 0xffff;
1709 ulg max_start;
1710
1711 if (max_block_size > s->pending_buf_size - 5) {
1712 max_block_size = s->pending_buf_size - 5;
1713 }
1714
1715 /* Copy as much as possible from input to output: */
1716 for (;;) {
1717 /* Fill the window as much as possible: */
1718 if (s->lookahead <= 1) {
1719
1720 Assert(s->strstart < s->w_size+MAX_DIST(s) ||
1721 s->block_start >= (long)s->w_size, "slide too late");
1722
1723 fill_window(s);
1724 if (s->lookahead == 0 && flush == Z_NO_FLUSH) return need_more;
1725
1726 if (s->lookahead == 0) break; /* flush the current block */
1727 }
1728 Assert(s->block_start >= 0L, "block gone");
1729
1730 s->strstart += s->lookahead;
1731 s->lookahead = 0;
1732
1733 /* Emit a stored block if pending_buf will be full: */
1734 max_start = s->block_start + max_block_size;
1735 if (s->strstart == 0 || (ulg)s->strstart >= max_start) {
1736 /* strstart == 0 is possible when wraparound on 16-bit machine */
1737 s->lookahead = (uInt)(s->strstart - max_start);
1738 s->strstart = (uInt)max_start;
1739 FLUSH_BLOCK(s, 0);
1740 }
1741 /* Flush if we may have to slide, otherwise block_start may become
1742 * negative and the data will be gone:
1743 */
1744 if (s->strstart - (uInt)s->block_start >= MAX_DIST(s)) {
1745 FLUSH_BLOCK(s, 0);
1746 }
1747 }
1748 FLUSH_BLOCK(s, flush == Z_FINISH);
1749 return flush == Z_FINISH ? finish_done : block_done;
1750 }
1751
1752 /* ===========================================================================
1753 * Compress as much as possible from the input stream, return the current
1754 * block state.
1755 * This function does not perform lazy evaluation of matches and inserts
1756 * new strings in the dictionary only for unmatched strings or for short
1757 * matches. It is used only for the fast compression options.
1758 */
deflate_fast(deflate_state * s,int flush)1759 local block_state deflate_fast(deflate_state *s, int flush)
1760 {
1761 IPos hash_head = NIL; /* head of the hash chain */
1762 int bflush; /* set if current block must be flushed */
1763
1764 for (;;) {
1765 /* Make sure that we always have enough lookahead, except
1766 * at the end of the input file. We need MAX_MATCH bytes
1767 * for the next match, plus MIN_MATCH bytes to insert the
1768 * string following the next match.
1769 */
1770 if (s->lookahead < MIN_LOOKAHEAD) {
1771 fill_window(s);
1772 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
1773 return need_more;
1774 }
1775 if (s->lookahead == 0) break; /* flush the current block */
1776 }
1777
1778 /* Insert the string window[strstart .. strstart+2] in the
1779 * dictionary, and set hash_head to the head of the hash chain:
1780 */
1781 if (s->lookahead >= MIN_MATCH) {
1782 INSERT_STRING(s, s->strstart, hash_head);
1783 }
1784
1785 /* Find the longest match, discarding those <= prev_length.
1786 * At this point we have always match_length < MIN_MATCH
1787 */
1788 if (hash_head != NIL && s->strstart - hash_head <= MAX_DIST(s)) {
1789 /* To simplify the code, we prevent matches with the string
1790 * of window index 0 (in particular we have to avoid a match
1791 * of the string with itself at the start of the input file).
1792 */
1793 if (s->strategy != Z_HUFFMAN_ONLY) {
1794 s->match_length = longest_match (s, hash_head);
1795 }
1796 /* longest_match() sets match_start */
1797 }
1798 if (s->match_length >= MIN_MATCH) {
1799 check_match(s, s->strstart, s->match_start, s->match_length);
1800
1801 _tr_tally_dist(s, s->strstart - s->match_start,
1802 s->match_length - MIN_MATCH, bflush);
1803
1804 s->lookahead -= s->match_length;
1805
1806 /* Insert new strings in the hash table only if the match length
1807 * is not too large. This saves time but degrades compression.
1808 */
1809 #ifndef FASTEST
1810 if (s->match_length <= s->max_insert_length &&
1811 s->lookahead >= MIN_MATCH) {
1812 s->match_length--; /* string at strstart already in hash table */
1813 do {
1814 s->strstart++;
1815 INSERT_STRING(s, s->strstart, hash_head);
1816 /* strstart never exceeds WSIZE-MAX_MATCH, so there are
1817 * always MIN_MATCH bytes ahead.
1818 */
1819 } while (--s->match_length != 0);
1820 s->strstart++;
1821 } else
1822 #endif
1823 {
1824 s->strstart += s->match_length;
1825 s->match_length = 0;
1826 s->ins_h = s->window[s->strstart];
1827 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
1828 #if MIN_MATCH != 3
1829 Call UPDATE_HASH() MIN_MATCH-3 more times
1830 #endif
1831 /* If lookahead < MIN_MATCH, ins_h is garbage, but it does not
1832 * matter since it will be recomputed at next deflate call.
1833 */
1834 }
1835 } else {
1836 /* No match, output a literal byte */
1837 Tracevv((stderr,"%c", s->window[s->strstart]));
1838 _tr_tally_lit (s, s->window[s->strstart], bflush);
1839 s->lookahead--;
1840 s->strstart++;
1841 }
1842 if (bflush) FLUSH_BLOCK(s, 0);
1843 }
1844 FLUSH_BLOCK(s, flush == Z_FINISH);
1845 return flush == Z_FINISH ? finish_done : block_done;
1846 }
1847
1848 /* ===========================================================================
1849 * Same as above, but achieves better compression. We use a lazy
1850 * evaluation for matches: a match is finally adopted only if there is
1851 * no better match at the next window position.
1852 */
deflate_slow(deflate_state * s,int flush)1853 local block_state deflate_slow(deflate_state *s, int flush)
1854 {
1855 IPos hash_head = NIL; /* head of hash chain */
1856 int bflush; /* set if current block must be flushed */
1857
1858 /* Process the input block. */
1859 for (;;) {
1860 /* Make sure that we always have enough lookahead, except
1861 * at the end of the input file. We need MAX_MATCH bytes
1862 * for the next match, plus MIN_MATCH bytes to insert the
1863 * string following the next match.
1864 */
1865 if (s->lookahead < MIN_LOOKAHEAD) {
1866 fill_window(s);
1867 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
1868 return need_more;
1869 }
1870 if (s->lookahead == 0) break; /* flush the current block */
1871 }
1872
1873 /* Insert the string window[strstart .. strstart+2] in the
1874 * dictionary, and set hash_head to the head of the hash chain:
1875 */
1876 if (s->lookahead >= MIN_MATCH) {
1877 INSERT_STRING(s, s->strstart, hash_head);
1878 }
1879
1880 /* Find the longest match, discarding those <= prev_length.
1881 */
1882 s->prev_length = s->match_length, s->prev_match = s->match_start;
1883 s->match_length = MIN_MATCH-1;
1884
1885 if (hash_head != NIL && s->prev_length < s->max_lazy_match &&
1886 s->strstart - hash_head <= MAX_DIST(s)) {
1887 /* To simplify the code, we prevent matches with the string
1888 * of window index 0 (in particular we have to avoid a match
1889 * of the string with itself at the start of the input file).
1890 */
1891 if (s->strategy != Z_HUFFMAN_ONLY) {
1892 s->match_length = longest_match (s, hash_head);
1893 }
1894 /* longest_match() sets match_start */
1895
1896 if (s->match_length <= 5 && (s->strategy == Z_FILTERED ||
1897 (s->match_length == MIN_MATCH &&
1898 s->strstart - s->match_start > TOO_FAR))) {
1899
1900 /* If prev_match is also MIN_MATCH, match_start is garbage
1901 * but we will ignore the current match anyway.
1902 */
1903 s->match_length = MIN_MATCH-1;
1904 }
1905 }
1906 /* If there was a match at the previous step and the current
1907 * match is not better, output the previous match:
1908 */
1909 if (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) {
1910 uInt max_insert = s->strstart + s->lookahead - MIN_MATCH;
1911 /* Do not insert strings in hash table beyond this. */
1912
1913 check_match(s, s->strstart-1, s->prev_match, s->prev_length);
1914
1915 _tr_tally_dist(s, s->strstart -1 - s->prev_match,
1916 s->prev_length - MIN_MATCH, bflush);
1917
1918 /* Insert in hash table all strings up to the end of the match.
1919 * strstart-1 and strstart are already inserted. If there is not
1920 * enough lookahead, the last two strings are not inserted in
1921 * the hash table.
1922 */
1923 s->lookahead -= s->prev_length-1;
1924 s->prev_length -= 2;
1925 do {
1926 if (++s->strstart <= max_insert) {
1927 INSERT_STRING(s, s->strstart, hash_head);
1928 }
1929 } while (--s->prev_length != 0);
1930 s->match_available = 0;
1931 s->match_length = MIN_MATCH-1;
1932 s->strstart++;
1933
1934 if (bflush) FLUSH_BLOCK(s, 0);
1935
1936 } else if (s->match_available) {
1937 /* If there was no match at the previous position, output a
1938 * single literal. If there was a match but the current match
1939 * is longer, truncate the previous match to a single literal.
1940 */
1941 Tracevv((stderr,"%c", s->window[s->strstart-1]));
1942 _tr_tally_lit(s, s->window[s->strstart-1], bflush);
1943 if (bflush) {
1944 FLUSH_BLOCK_ONLY(s, 0);
1945 }
1946 s->strstart++;
1947 s->lookahead--;
1948 if (s->strm->avail_out == 0) return need_more;
1949 } else {
1950 /* There is no previous match to compare with, wait for
1951 * the next step to decide.
1952 */
1953 s->match_available = 1;
1954 s->strstart++;
1955 s->lookahead--;
1956 }
1957 }
1958 Assert (flush != Z_NO_FLUSH, "no flush?");
1959 if (s->match_available) {
1960 Tracevv((stderr,"%c", s->window[s->strstart-1]));
1961 _tr_tally_lit(s, s->window[s->strstart-1], bflush);
1962 s->match_available = 0;
1963 }
1964 FLUSH_BLOCK(s, flush == Z_FINISH);
1965 return flush == Z_FINISH ? finish_done : block_done;
1966 }
1967 /* --- deflate.c */
1968
1969 /* +++ trees.c */
1970
1971 /* trees.c -- output deflated data using Huffman coding
1972 * Copyright (C) 1995-2002 Jean-loup Gailly
1973 * For conditions of distribution and use, see copyright notice in zlib.h
1974 */
1975
1976 /*
1977 * ALGORITHM
1978 *
1979 * The "deflation" process uses several Huffman trees. The more
1980 * common source values are represented by shorter bit sequences.
1981 *
1982 * Each code tree is stored in a compressed form which is itself
1983 * a Huffman encoding of the lengths of all the code strings (in
1984 * ascending order by source values). The actual code strings are
1985 * reconstructed from the lengths in the inflate process, as described
1986 * in the deflate specification.
1987 *
1988 * REFERENCES
1989 *
1990 * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification".
1991 * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc
1992 *
1993 * Storer, James A.
1994 * Data Compression: Methods and Theory, pp. 49-50.
1995 * Computer Science Press, 1988. ISBN 0-7167-8156-5.
1996 *
1997 * Sedgewick, R.
1998 * Algorithms, p290.
1999 * Addison-Wesley, 1983. ISBN 0-201-06672-6.
2000 */
2001
2002 /* @(#) $Id: zlib.c,v 1.39 2024/07/04 01:10:17 rin Exp $ */
2003
2004 /* #define GEN_TREES_H */
2005
2006 /* #include "deflate.h" */
2007
2008 #ifdef DEBUG_ZLIB
2009 # include <ctype.h>
2010 #endif
2011
2012 /* ===========================================================================
2013 * Constants
2014 */
2015
2016 #define MAX_BL_BITS 7
2017 /* Bit length codes must not exceed MAX_BL_BITS bits */
2018
2019 #define END_BLOCK 256
2020 /* end of block literal code */
2021
2022 #define REP_3_6 16
2023 /* repeat previous bit length 3-6 times (2 bits of repeat count) */
2024
2025 #define REPZ_3_10 17
2026 /* repeat a zero length 3-10 times (3 bits of repeat count) */
2027
2028 #define REPZ_11_138 18
2029 /* repeat a zero length 11-138 times (7 bits of repeat count) */
2030
2031 local const int extra_lbits[LENGTH_CODES] /* extra bits for each length code */
2032 = {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};
2033
2034 local const int extra_dbits[D_CODES] /* extra bits for each distance code */
2035 = {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};
2036
2037 local const int extra_blbits[BL_CODES]/* extra bits for each bit length code */
2038 = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7};
2039
2040 local const uch bl_order[BL_CODES]
2041 = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15};
2042 /* The lengths of the bit length codes are sent in order of decreasing
2043 * probability, to avoid transmitting the lengths for unused bit length codes.
2044 */
2045
2046 #define Buf_size (8 * 2*sizeof(char))
2047 /* Number of bits used within bi_buf. (bi_buf might be implemented on
2048 * more than 16 bits on some systems.)
2049 */
2050
2051 /* ===========================================================================
2052 * Local data. These are initialized only once.
2053 */
2054
2055 #define DIST_CODE_LEN 512 /* see definition of array dist_code below */
2056
2057 #if defined(GEN_TREES_H) || !defined(STDC)
2058 /* non ANSI compilers may not accept trees.h */
2059
2060 local ct_data static_ltree[L_CODES+2];
2061 /* The static literal tree. Since the bit lengths are imposed, there is no
2062 * need for the L_CODES extra codes used during heap construction. However
2063 * The codes 286 and 287 are needed to build a canonical tree (see _tr_init
2064 * below).
2065 */
2066
2067 local ct_data static_dtree[D_CODES];
2068 /* The static distance tree. (Actually a trivial tree since all codes use
2069 * 5 bits.)
2070 */
2071
2072 uch _dist_code[DIST_CODE_LEN];
2073 /* Distance codes. The first 256 values correspond to the distances
2074 * 3 .. 258, the last 256 values correspond to the top 8 bits of
2075 * the 15 bit distances.
2076 */
2077
2078 uch _length_code[MAX_MATCH-MIN_MATCH+1];
2079 /* length code for each normalized match length (0 == MIN_MATCH) */
2080
2081 local int base_length[LENGTH_CODES];
2082 /* First normalized length for each code (0 = MIN_MATCH) */
2083
2084 local int base_dist[D_CODES];
2085 /* First normalized distance for each code (0 = distance of 1) */
2086
2087 #else
2088 /* +++ trees.h */
2089
2090 /* header created automatically with -DGEN_TREES_H */
2091
2092 local const ct_data static_ltree[L_CODES+2] = {
2093 {{ 12},{ 8}}, {{140},{ 8}}, {{ 76},{ 8}}, {{204},{ 8}}, {{ 44},{ 8}},
2094 {{172},{ 8}}, {{108},{ 8}}, {{236},{ 8}}, {{ 28},{ 8}}, {{156},{ 8}},
2095 {{ 92},{ 8}}, {{220},{ 8}}, {{ 60},{ 8}}, {{188},{ 8}}, {{124},{ 8}},
2096 {{252},{ 8}}, {{ 2},{ 8}}, {{130},{ 8}}, {{ 66},{ 8}}, {{194},{ 8}},
2097 {{ 34},{ 8}}, {{162},{ 8}}, {{ 98},{ 8}}, {{226},{ 8}}, {{ 18},{ 8}},
2098 {{146},{ 8}}, {{ 82},{ 8}}, {{210},{ 8}}, {{ 50},{ 8}}, {{178},{ 8}},
2099 {{114},{ 8}}, {{242},{ 8}}, {{ 10},{ 8}}, {{138},{ 8}}, {{ 74},{ 8}},
2100 {{202},{ 8}}, {{ 42},{ 8}}, {{170},{ 8}}, {{106},{ 8}}, {{234},{ 8}},
2101 {{ 26},{ 8}}, {{154},{ 8}}, {{ 90},{ 8}}, {{218},{ 8}}, {{ 58},{ 8}},
2102 {{186},{ 8}}, {{122},{ 8}}, {{250},{ 8}}, {{ 6},{ 8}}, {{134},{ 8}},
2103 {{ 70},{ 8}}, {{198},{ 8}}, {{ 38},{ 8}}, {{166},{ 8}}, {{102},{ 8}},
2104 {{230},{ 8}}, {{ 22},{ 8}}, {{150},{ 8}}, {{ 86},{ 8}}, {{214},{ 8}},
2105 {{ 54},{ 8}}, {{182},{ 8}}, {{118},{ 8}}, {{246},{ 8}}, {{ 14},{ 8}},
2106 {{142},{ 8}}, {{ 78},{ 8}}, {{206},{ 8}}, {{ 46},{ 8}}, {{174},{ 8}},
2107 {{110},{ 8}}, {{238},{ 8}}, {{ 30},{ 8}}, {{158},{ 8}}, {{ 94},{ 8}},
2108 {{222},{ 8}}, {{ 62},{ 8}}, {{190},{ 8}}, {{126},{ 8}}, {{254},{ 8}},
2109 {{ 1},{ 8}}, {{129},{ 8}}, {{ 65},{ 8}}, {{193},{ 8}}, {{ 33},{ 8}},
2110 {{161},{ 8}}, {{ 97},{ 8}}, {{225},{ 8}}, {{ 17},{ 8}}, {{145},{ 8}},
2111 {{ 81},{ 8}}, {{209},{ 8}}, {{ 49},{ 8}}, {{177},{ 8}}, {{113},{ 8}},
2112 {{241},{ 8}}, {{ 9},{ 8}}, {{137},{ 8}}, {{ 73},{ 8}}, {{201},{ 8}},
2113 {{ 41},{ 8}}, {{169},{ 8}}, {{105},{ 8}}, {{233},{ 8}}, {{ 25},{ 8}},
2114 {{153},{ 8}}, {{ 89},{ 8}}, {{217},{ 8}}, {{ 57},{ 8}}, {{185},{ 8}},
2115 {{121},{ 8}}, {{249},{ 8}}, {{ 5},{ 8}}, {{133},{ 8}}, {{ 69},{ 8}},
2116 {{197},{ 8}}, {{ 37},{ 8}}, {{165},{ 8}}, {{101},{ 8}}, {{229},{ 8}},
2117 {{ 21},{ 8}}, {{149},{ 8}}, {{ 85},{ 8}}, {{213},{ 8}}, {{ 53},{ 8}},
2118 {{181},{ 8}}, {{117},{ 8}}, {{245},{ 8}}, {{ 13},{ 8}}, {{141},{ 8}},
2119 {{ 77},{ 8}}, {{205},{ 8}}, {{ 45},{ 8}}, {{173},{ 8}}, {{109},{ 8}},
2120 {{237},{ 8}}, {{ 29},{ 8}}, {{157},{ 8}}, {{ 93},{ 8}}, {{221},{ 8}},
2121 {{ 61},{ 8}}, {{189},{ 8}}, {{125},{ 8}}, {{253},{ 8}}, {{ 19},{ 9}},
2122 {{275},{ 9}}, {{147},{ 9}}, {{403},{ 9}}, {{ 83},{ 9}}, {{339},{ 9}},
2123 {{211},{ 9}}, {{467},{ 9}}, {{ 51},{ 9}}, {{307},{ 9}}, {{179},{ 9}},
2124 {{435},{ 9}}, {{115},{ 9}}, {{371},{ 9}}, {{243},{ 9}}, {{499},{ 9}},
2125 {{ 11},{ 9}}, {{267},{ 9}}, {{139},{ 9}}, {{395},{ 9}}, {{ 75},{ 9}},
2126 {{331},{ 9}}, {{203},{ 9}}, {{459},{ 9}}, {{ 43},{ 9}}, {{299},{ 9}},
2127 {{171},{ 9}}, {{427},{ 9}}, {{107},{ 9}}, {{363},{ 9}}, {{235},{ 9}},
2128 {{491},{ 9}}, {{ 27},{ 9}}, {{283},{ 9}}, {{155},{ 9}}, {{411},{ 9}},
2129 {{ 91},{ 9}}, {{347},{ 9}}, {{219},{ 9}}, {{475},{ 9}}, {{ 59},{ 9}},
2130 {{315},{ 9}}, {{187},{ 9}}, {{443},{ 9}}, {{123},{ 9}}, {{379},{ 9}},
2131 {{251},{ 9}}, {{507},{ 9}}, {{ 7},{ 9}}, {{263},{ 9}}, {{135},{ 9}},
2132 {{391},{ 9}}, {{ 71},{ 9}}, {{327},{ 9}}, {{199},{ 9}}, {{455},{ 9}},
2133 {{ 39},{ 9}}, {{295},{ 9}}, {{167},{ 9}}, {{423},{ 9}}, {{103},{ 9}},
2134 {{359},{ 9}}, {{231},{ 9}}, {{487},{ 9}}, {{ 23},{ 9}}, {{279},{ 9}},
2135 {{151},{ 9}}, {{407},{ 9}}, {{ 87},{ 9}}, {{343},{ 9}}, {{215},{ 9}},
2136 {{471},{ 9}}, {{ 55},{ 9}}, {{311},{ 9}}, {{183},{ 9}}, {{439},{ 9}},
2137 {{119},{ 9}}, {{375},{ 9}}, {{247},{ 9}}, {{503},{ 9}}, {{ 15},{ 9}},
2138 {{271},{ 9}}, {{143},{ 9}}, {{399},{ 9}}, {{ 79},{ 9}}, {{335},{ 9}},
2139 {{207},{ 9}}, {{463},{ 9}}, {{ 47},{ 9}}, {{303},{ 9}}, {{175},{ 9}},
2140 {{431},{ 9}}, {{111},{ 9}}, {{367},{ 9}}, {{239},{ 9}}, {{495},{ 9}},
2141 {{ 31},{ 9}}, {{287},{ 9}}, {{159},{ 9}}, {{415},{ 9}}, {{ 95},{ 9}},
2142 {{351},{ 9}}, {{223},{ 9}}, {{479},{ 9}}, {{ 63},{ 9}}, {{319},{ 9}},
2143 {{191},{ 9}}, {{447},{ 9}}, {{127},{ 9}}, {{383},{ 9}}, {{255},{ 9}},
2144 {{511},{ 9}}, {{ 0},{ 7}}, {{ 64},{ 7}}, {{ 32},{ 7}}, {{ 96},{ 7}},
2145 {{ 16},{ 7}}, {{ 80},{ 7}}, {{ 48},{ 7}}, {{112},{ 7}}, {{ 8},{ 7}},
2146 {{ 72},{ 7}}, {{ 40},{ 7}}, {{104},{ 7}}, {{ 24},{ 7}}, {{ 88},{ 7}},
2147 {{ 56},{ 7}}, {{120},{ 7}}, {{ 4},{ 7}}, {{ 68},{ 7}}, {{ 36},{ 7}},
2148 {{100},{ 7}}, {{ 20},{ 7}}, {{ 84},{ 7}}, {{ 52},{ 7}}, {{116},{ 7}},
2149 {{ 3},{ 8}}, {{131},{ 8}}, {{ 67},{ 8}}, {{195},{ 8}}, {{ 35},{ 8}},
2150 {{163},{ 8}}, {{ 99},{ 8}}, {{227},{ 8}}
2151 };
2152
2153 local const ct_data static_dtree[D_CODES] = {
2154 {{ 0},{ 5}}, {{16},{ 5}}, {{ 8},{ 5}}, {{24},{ 5}}, {{ 4},{ 5}},
2155 {{20},{ 5}}, {{12},{ 5}}, {{28},{ 5}}, {{ 2},{ 5}}, {{18},{ 5}},
2156 {{10},{ 5}}, {{26},{ 5}}, {{ 6},{ 5}}, {{22},{ 5}}, {{14},{ 5}},
2157 {{30},{ 5}}, {{ 1},{ 5}}, {{17},{ 5}}, {{ 9},{ 5}}, {{25},{ 5}},
2158 {{ 5},{ 5}}, {{21},{ 5}}, {{13},{ 5}}, {{29},{ 5}}, {{ 3},{ 5}},
2159 {{19},{ 5}}, {{11},{ 5}}, {{27},{ 5}}, {{ 7},{ 5}}, {{23},{ 5}}
2160 };
2161
2162 const uch _dist_code[DIST_CODE_LEN] = {
2163 0, 1, 2, 3, 4, 4, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8, 8,
2164 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 10,
2165 10, 10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11,
2166 11, 11, 11, 11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
2167 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 13, 13, 13, 13,
2168 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13,
2169 13, 13, 13, 13, 13, 13, 13, 13, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
2170 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
2171 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
2172 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 15, 15, 15, 15, 15, 15, 15, 15,
2173 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
2174 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
2175 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 0, 0, 16, 17,
2176 18, 18, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 22, 22, 22, 22, 22, 22, 22, 22,
2177 23, 23, 23, 23, 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
2178 24, 24, 24, 24, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
2179 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
2180 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 27, 27, 27, 27, 27, 27, 27, 27,
2181 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
2182 27, 27, 27, 27, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
2183 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
2184 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
2185 28, 28, 28, 28, 28, 28, 28, 28, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
2186 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
2187 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
2188 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29
2189 };
2190
2191 const uch _length_code[MAX_MATCH-MIN_MATCH+1]= {
2192 0, 1, 2, 3, 4, 5, 6, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 12, 12,
2193 13, 13, 13, 13, 14, 14, 14, 14, 15, 15, 15, 15, 16, 16, 16, 16, 16, 16, 16, 16,
2194 17, 17, 17, 17, 17, 17, 17, 17, 18, 18, 18, 18, 18, 18, 18, 18, 19, 19, 19, 19,
2195 19, 19, 19, 19, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20,
2196 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 22, 22, 22, 22,
2197 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 23, 23, 23, 23, 23, 23, 23, 23,
2198 23, 23, 23, 23, 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
2199 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
2200 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
2201 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 26, 26, 26, 26, 26, 26, 26, 26,
2202 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
2203 26, 26, 26, 26, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
2204 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 28
2205 };
2206
2207 local const int base_length[LENGTH_CODES] = {
2208 0, 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, 16, 20, 24, 28, 32, 40, 48, 56,
2209 64, 80, 96, 112, 128, 160, 192, 224, 0
2210 };
2211
2212 local const int base_dist[D_CODES] = {
2213 0, 1, 2, 3, 4, 6, 8, 12, 16, 24,
2214 32, 48, 64, 96, 128, 192, 256, 384, 512, 768,
2215 1024, 1536, 2048, 3072, 4096, 6144, 8192, 12288, 16384, 24576
2216 };
2217 /* --- trees.h */
2218
2219 #endif /* GEN_TREES_H */
2220
2221 struct static_tree_desc_s {
2222 const ct_data *static_tree; /* static tree or NULL */
2223 const intf *extra_bits; /* extra bits for each code or NULL */
2224 int extra_base; /* base index for extra_bits */
2225 int elems; /* max number of elements in the tree */
2226 int max_length; /* max bit length for the codes */
2227 };
2228
2229 local static_tree_desc static_l_desc =
2230 {static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS};
2231
2232 local static_tree_desc static_d_desc =
2233 {static_dtree, extra_dbits, 0, D_CODES, MAX_BITS};
2234
2235 local static_tree_desc static_bl_desc =
2236 {(const ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS};
2237
2238 /* ===========================================================================
2239 * Local (static) routines in this file.
2240 */
2241
2242 local void tr_static_init(void);
2243 local void init_block(deflate_state *s);
2244 local void pqdownheap(deflate_state *s, ct_data *tree, int k);
2245 local void gen_bitlen(deflate_state *s, tree_desc *desc);
2246 local void gen_codes(ct_data *tree, int max_code, ushf *bl_count);
2247 local void build_tree(deflate_state *s, tree_desc *desc);
2248 local void scan_tree(deflate_state *s, ct_data *tree, int max_code);
2249 local void send_tree(deflate_state *s, ct_data *tree, int max_code);
2250 local int build_bl_tree(deflate_state *s);
2251 local void send_all_trees(deflate_state *s, int lcodes, int dcodes,
2252 int blcodes);
2253 local void compress_block(deflate_state *s, const ct_data *ltree,
2254 const ct_data *dtree);
2255 local void set_data_type(deflate_state *s);
2256 local unsigned bi_reverse(unsigned value, int length);
2257 local void bi_windup(deflate_state *s);
2258 local void bi_flush(deflate_state *s);
2259 local void copy_block(deflate_state *s, charf *buf, unsigned len,
2260 int header);
2261
2262 #ifdef GEN_TREES_H
2263 local void gen_trees_header(void);
2264 #endif
2265
2266 #ifndef DEBUG_ZLIB
2267 # define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len)
2268 /* Send a code of the given tree. c and tree must not have side effects */
2269
2270 #else /* DEBUG_ZLIB */
2271 # define send_code(s, c, tree) \
2272 { if (z_verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \
2273 send_bits(s, tree[c].Code, tree[c].Len); }
2274 #endif
2275
2276 /* ===========================================================================
2277 * Output a short LSB first on the stream.
2278 * IN assertion: there is enough room in pendingBuf.
2279 */
2280 #define put_short(s, w) { \
2281 put_byte(s, (uch)((w) & 0xff)); \
2282 put_byte(s, (uch)((ush)(w) >> 8)); \
2283 }
2284
2285 /* ===========================================================================
2286 * Send a value on a given number of bits.
2287 * IN assertion: length <= 16 and value fits in length bits.
2288 */
2289 #ifdef DEBUG_ZLIB
2290 local void send_bits(deflate_state *s, int value, int length);
2291
send_bits(s,value,length)2292 local void send_bits(s, value, length)
2293 deflate_state *s;
2294 int value; /* value to send */
2295 int length; /* number of bits */
2296 {
2297 Tracevv((stderr," l %2d v %4x ", length, value));
2298 Assert(length > 0 && length <= 15, "invalid length");
2299 s->bits_sent += (ulg)length;
2300
2301 /* If not enough room in bi_buf, use (valid) bits from bi_buf and
2302 * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid))
2303 * unused bits in value.
2304 */
2305 if (s->bi_valid > (int)Buf_size - length) {
2306 s->bi_buf |= (value << s->bi_valid);
2307 put_short(s, s->bi_buf);
2308 s->bi_buf = (ush)value >> (Buf_size - s->bi_valid);
2309 s->bi_valid += length - Buf_size;
2310 } else {
2311 s->bi_buf |= value << s->bi_valid;
2312 s->bi_valid += length;
2313 }
2314 }
2315 #else /* !DEBUG_ZLIB */
2316
2317 #define send_bits(s, value, length) \
2318 { int len = length;\
2319 if (s->bi_valid > (int)Buf_size - len) {\
2320 int val = value;\
2321 s->bi_buf |= (val << s->bi_valid);\
2322 put_short(s, s->bi_buf);\
2323 s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\
2324 s->bi_valid += len - Buf_size;\
2325 } else {\
2326 s->bi_buf |= (value) << s->bi_valid;\
2327 s->bi_valid += len;\
2328 }\
2329 }
2330 #endif /* DEBUG_ZLIB */
2331
2332
2333 /* ===========================================================================
2334 * Initialize the various 'constant' tables.
2335 */
tr_static_init(void)2336 local void tr_static_init(void)
2337 {
2338 #if defined(GEN_TREES_H) || !defined(STDC)
2339 static int static_init_done = 0;
2340 int n; /* iterates over tree elements */
2341 int bits; /* bit counter */
2342 int length; /* length value */
2343 int code; /* code value */
2344 int dist; /* distance index */
2345 ush bl_count[MAX_BITS+1];
2346 /* number of codes at each bit length for an optimal tree */
2347
2348 if (static_init_done) return;
2349
2350 /* For some embedded targets, global variables are not initialized: */
2351 static_l_desc.static_tree = static_ltree;
2352 static_l_desc.extra_bits = extra_lbits;
2353 static_d_desc.static_tree = static_dtree;
2354 static_d_desc.extra_bits = extra_dbits;
2355 static_bl_desc.extra_bits = extra_blbits;
2356
2357 /* Initialize the mapping length (0..255) -> length code (0..28) */
2358 length = 0;
2359 for (code = 0; code < LENGTH_CODES-1; code++) {
2360 base_length[code] = length;
2361 for (n = 0; n < (1<<extra_lbits[code]); n++) {
2362 _length_code[length++] = (uch)code;
2363 }
2364 }
2365 Assert (length == 256, "tr_static_init: length != 256");
2366 /* Note that the length 255 (match length 258) can be represented
2367 * in two different ways: code 284 + 5 bits or code 285, so we
2368 * overwrite length_code[255] to use the best encoding:
2369 */
2370 _length_code[length-1] = (uch)code;
2371
2372 /* Initialize the mapping dist (0..32K) -> dist code (0..29) */
2373 dist = 0;
2374 for (code = 0 ; code < 16; code++) {
2375 base_dist[code] = dist;
2376 for (n = 0; n < (1<<extra_dbits[code]); n++) {
2377 _dist_code[dist++] = (uch)code;
2378 }
2379 }
2380 Assert (dist == 256, "tr_static_init: dist != 256");
2381 dist >>= 7; /* from now on, all distances are divided by 128 */
2382 for ( ; code < D_CODES; code++) {
2383 base_dist[code] = dist << 7;
2384 for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) {
2385 _dist_code[256 + dist++] = (uch)code;
2386 }
2387 }
2388 Assert (dist == 256, "tr_static_init: 256+dist != 512");
2389
2390 /* Construct the codes of the static literal tree */
2391 for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
2392 n = 0;
2393 while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++;
2394 while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++;
2395 while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++;
2396 while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++;
2397 /* Codes 286 and 287 do not exist, but we must include them in the
2398 * tree construction to get a canonical Huffman tree (longest code
2399 * all ones)
2400 */
2401 gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count);
2402
2403 /* The static distance tree is trivial: */
2404 for (n = 0; n < D_CODES; n++) {
2405 static_dtree[n].Len = 5;
2406 static_dtree[n].Code = bi_reverse((unsigned)n, 5);
2407 }
2408 static_init_done = 1;
2409
2410 # ifdef GEN_TREES_H
2411 gen_trees_header();
2412 # endif
2413 #endif /* defined(GEN_TREES_H) || !defined(STDC) */
2414 }
2415
2416 /* ===========================================================================
2417 * Genererate the file trees.h describing the static trees.
2418 */
2419 #ifdef GEN_TREES_H
2420 # ifndef DEBUG_ZLIB
2421 # include <stdio.h>
2422 # endif
2423
2424 # define SEPARATOR(i, last, width) \
2425 ((i) == (last)? "\n};\n\n" : \
2426 ((i) % (width) == (width)-1 ? ",\n" : ", "))
2427
gen_trees_header(void)2428 void gen_trees_header(void)
2429 {
2430 FILE *header = fopen("trees.h", "w");
2431 int i;
2432
2433 Assert (header != NULL, "Can't open trees.h");
2434 fprintf(header,
2435 "/* header created automatically with -DGEN_TREES_H */\n\n");
2436
2437 fprintf(header, "local const ct_data static_ltree[L_CODES+2] = {\n");
2438 for (i = 0; i < L_CODES+2; i++) {
2439 fprintf(header, "{{%3u},{%3u}}%s", static_ltree[i].Code,
2440 static_ltree[i].Len, SEPARATOR(i, L_CODES+1, 5));
2441 }
2442
2443 fprintf(header, "local const ct_data static_dtree[D_CODES] = {\n");
2444 for (i = 0; i < D_CODES; i++) {
2445 fprintf(header, "{{%2u},{%2u}}%s", static_dtree[i].Code,
2446 static_dtree[i].Len, SEPARATOR(i, D_CODES-1, 5));
2447 }
2448
2449 fprintf(header, "const uch _dist_code[DIST_CODE_LEN] = {\n");
2450 for (i = 0; i < DIST_CODE_LEN; i++) {
2451 fprintf(header, "%2u%s", _dist_code[i],
2452 SEPARATOR(i, DIST_CODE_LEN-1, 20));
2453 }
2454
2455 fprintf(header, "const uch _length_code[MAX_MATCH-MIN_MATCH+1]= {\n");
2456 for (i = 0; i < MAX_MATCH-MIN_MATCH+1; i++) {
2457 fprintf(header, "%2u%s", _length_code[i],
2458 SEPARATOR(i, MAX_MATCH-MIN_MATCH, 20));
2459 }
2460
2461 fprintf(header, "local const int base_length[LENGTH_CODES] = {\n");
2462 for (i = 0; i < LENGTH_CODES; i++) {
2463 fprintf(header, "%1u%s", base_length[i],
2464 SEPARATOR(i, LENGTH_CODES-1, 20));
2465 }
2466
2467 fprintf(header, "local const int base_dist[D_CODES] = {\n");
2468 for (i = 0; i < D_CODES; i++) {
2469 fprintf(header, "%5u%s", base_dist[i],
2470 SEPARATOR(i, D_CODES-1, 10));
2471 }
2472
2473 fclose(header);
2474 }
2475 #endif /* GEN_TREES_H */
2476
2477 /* ===========================================================================
2478 * Initialize the tree data structures for a new zlib stream.
2479 */
_tr_init(deflate_state * s)2480 void _tr_init(deflate_state *s)
2481 {
2482 tr_static_init();
2483
2484 s->l_desc.dyn_tree = s->dyn_ltree;
2485 s->l_desc.stat_desc = &static_l_desc;
2486
2487 s->d_desc.dyn_tree = s->dyn_dtree;
2488 s->d_desc.stat_desc = &static_d_desc;
2489
2490 s->bl_desc.dyn_tree = s->bl_tree;
2491 s->bl_desc.stat_desc = &static_bl_desc;
2492
2493 s->bi_buf = 0;
2494 s->bi_valid = 0;
2495 s->last_eob_len = 8; /* enough lookahead for inflate */
2496 #ifdef DEBUG_ZLIB
2497 s->compressed_len = 0L;
2498 s->bits_sent = 0L;
2499 #endif
2500
2501 /* Initialize the first block of the first file: */
2502 init_block(s);
2503 }
2504
2505 /* ===========================================================================
2506 * Initialize a new block.
2507 */
init_block(deflate_state * s)2508 local void init_block(deflate_state *s)
2509 {
2510 int n; /* iterates over tree elements */
2511
2512 /* Initialize the trees. */
2513 for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0;
2514 for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0;
2515 for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0;
2516
2517 s->dyn_ltree[END_BLOCK].Freq = 1;
2518 s->opt_len = s->static_len = 0L;
2519 s->last_lit = s->matches = 0;
2520 }
2521
2522 #define SMALLEST 1
2523 /* Index within the heap array of least frequent node in the Huffman tree */
2524
2525
2526 /* ===========================================================================
2527 * Remove the smallest element from the heap and recreate the heap with
2528 * one less element. Updates heap and heap_len.
2529 */
2530 #define pqremove(s, tree, top) \
2531 {\
2532 top = s->heap[SMALLEST]; \
2533 s->heap[SMALLEST] = s->heap[s->heap_len--]; \
2534 pqdownheap(s, tree, SMALLEST); \
2535 }
2536
2537 /* ===========================================================================
2538 * Compares to subtrees, using the tree depth as tie breaker when
2539 * the subtrees have equal frequency. This minimizes the worst case length.
2540 */
2541 #define smaller(tree, n, m, depth) \
2542 (tree[n].Freq < tree[m].Freq || \
2543 (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m]))
2544
2545 /* ===========================================================================
2546 * Restore the heap property by moving down the tree starting at node k,
2547 * exchanging a node with the smallest of its two sons if necessary, stopping
2548 * when the heap property is re-established (each father smaller than its
2549 * two sons).
2550 */
pqdownheap(deflate_state * s,ct_data * tree,int k)2551 local void pqdownheap(deflate_state *s,
2552 ct_data *tree, /* the tree to restore */
2553 int k) /* node to move down */
2554 {
2555 int v = s->heap[k];
2556 int j = k << 1; /* left son of k */
2557 while (j <= s->heap_len) {
2558 /* Set j to the smallest of the two sons: */
2559 if (j < s->heap_len &&
2560 smaller(tree, s->heap[j+1], s->heap[j], s->depth)) {
2561 j++;
2562 }
2563 /* Exit if v is smaller than both sons */
2564 if (smaller(tree, v, s->heap[j], s->depth)) break;
2565
2566 /* Exchange v with the smallest son */
2567 s->heap[k] = s->heap[j]; k = j;
2568
2569 /* And continue down the tree, setting j to the left son of k */
2570 j <<= 1;
2571 }
2572 s->heap[k] = v;
2573 }
2574
2575 /* ===========================================================================
2576 * Compute the optimal bit lengths for a tree and update the total bit length
2577 * for the current block.
2578 * IN assertion: the fields freq and dad are set, heap[heap_max] and
2579 * above are the tree nodes sorted by increasing frequency.
2580 * OUT assertions: the field len is set to the optimal bit length, the
2581 * array bl_count contains the frequencies for each bit length.
2582 * The length opt_len is updated; static_len is also updated if stree is
2583 * not null.
2584 */
gen_bitlen(deflate_state * s,tree_desc * desc)2585 local void gen_bitlen(deflate_state *s,
2586 tree_desc *desc) /* the tree descriptor */
2587 {
2588 ct_data *tree = desc->dyn_tree;
2589 int max_code = desc->max_code;
2590 const ct_data *stree = desc->stat_desc->static_tree;
2591 const intf *extra = desc->stat_desc->extra_bits;
2592 int base = desc->stat_desc->extra_base;
2593 int max_length = desc->stat_desc->max_length;
2594 int h; /* heap index */
2595 int n, m; /* iterate over the tree elements */
2596 int bits; /* bit length */
2597 int xbits; /* extra bits */
2598 ush f; /* frequency */
2599 int overflow = 0; /* number of elements with bit length too large */
2600
2601 for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0;
2602
2603 /* In a first pass, compute the optimal bit lengths (which may
2604 * overflow in the case of the bit length tree).
2605 */
2606 tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */
2607
2608 for (h = s->heap_max+1; h < HEAP_SIZE; h++) {
2609 n = s->heap[h];
2610 bits = tree[tree[n].Dad].Len + 1;
2611 if (bits > max_length) bits = max_length, overflow++;
2612 tree[n].Len = (ush)bits;
2613 /* We overwrite tree[n].Dad which is no longer needed */
2614
2615 if (n > max_code) continue; /* not a leaf node */
2616
2617 s->bl_count[bits]++;
2618 xbits = 0;
2619 if (n >= base) xbits = extra[n-base];
2620 f = tree[n].Freq;
2621 s->opt_len += (ulg)f * (bits + xbits);
2622 if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits);
2623 }
2624 if (overflow == 0) return;
2625
2626 Trace((stderr,"\nbit length overflow\n"));
2627 /* This happens for example on obj2 and pic of the Calgary corpus */
2628
2629 /* Find the first bit length which could increase: */
2630 do {
2631 bits = max_length-1;
2632 while (s->bl_count[bits] == 0) bits--;
2633 s->bl_count[bits]--; /* move one leaf down the tree */
2634 s->bl_count[bits+1] += 2; /* move one overflow item as its brother */
2635 s->bl_count[max_length]--;
2636 /* The brother of the overflow item also moves one step up,
2637 * but this does not affect bl_count[max_length]
2638 */
2639 overflow -= 2;
2640 } while (overflow > 0);
2641
2642 /* Now recompute all bit lengths, scanning in increasing frequency.
2643 * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
2644 * lengths instead of fixing only the wrong ones. This idea is taken
2645 * from 'ar' written by Haruhiko Okumura.)
2646 */
2647 for (bits = max_length; bits != 0; bits--) {
2648 n = s->bl_count[bits];
2649 while (n != 0) {
2650 m = s->heap[--h];
2651 if (m > max_code) continue;
2652 if (tree[m].Len != (unsigned) bits) {
2653 Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits));
2654 s->opt_len += ((long)bits - (long)tree[m].Len)
2655 *(long)tree[m].Freq;
2656 tree[m].Len = (ush)bits;
2657 }
2658 n--;
2659 }
2660 }
2661 }
2662
2663 /* ===========================================================================
2664 * Generate the codes for a given tree and bit counts (which need not be
2665 * optimal).
2666 * IN assertion: the array bl_count contains the bit length statistics for
2667 * the given tree and the field len is set for all tree elements.
2668 * OUT assertion: the field code is set for all tree elements of non
2669 * zero code length.
2670 */
gen_codes(ct_data * tree,int max_code,ushf * bl_count)2671 local void gen_codes (ct_data *tree, /* the tree to decorate */
2672 int max_code, /* largest code with non zero frequency */
2673 ushf *bl_count) /* number of codes at each bit length */
2674 {
2675 ush next_code[MAX_BITS+1]; /* next code value for each bit length */
2676 ush code = 0; /* running code value */
2677 int bits; /* bit index */
2678 int n; /* code index */
2679
2680 /* The distribution counts are first used to generate the code values
2681 * without bit reversal.
2682 */
2683 for (bits = 1; bits <= MAX_BITS; bits++) {
2684 next_code[bits] = code = (code + bl_count[bits-1]) << 1;
2685 }
2686 /* Check that the bit counts in bl_count are consistent. The last code
2687 * must be all ones.
2688 */
2689 Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1,
2690 "inconsistent bit counts");
2691 Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
2692
2693 for (n = 0; n <= max_code; n++) {
2694 int len = tree[n].Len;
2695 if (len == 0) continue;
2696 /* Now reverse the bits */
2697 tree[n].Code = bi_reverse(next_code[len]++, len);
2698
2699 Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
2700 n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1));
2701 }
2702 }
2703
2704 /* ===========================================================================
2705 * Construct one Huffman tree and assigns the code bit strings and lengths.
2706 * Update the total bit length for the current block.
2707 * IN assertion: the field freq is set for all tree elements.
2708 * OUT assertions: the fields len and code are set to the optimal bit length
2709 * and corresponding code. The length opt_len is updated; static_len is
2710 * also updated if stree is not null. The field max_code is set.
2711 */
build_tree(deflate_state * s,tree_desc * desc)2712 local void build_tree(deflate_state *s,
2713 tree_desc *desc) /* the tree descriptor */
2714 {
2715 ct_data *tree = desc->dyn_tree;
2716 const ct_data *stree = desc->stat_desc->static_tree;
2717 int elems = desc->stat_desc->elems;
2718 int n, m; /* iterate over heap elements */
2719 int max_code = -1; /* largest code with non zero frequency */
2720 int node; /* new node being created */
2721
2722 /* Construct the initial heap, with least frequent element in
2723 * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
2724 * heap[0] is not used.
2725 */
2726 s->heap_len = 0, s->heap_max = HEAP_SIZE;
2727
2728 for (n = 0; n < elems; n++) {
2729 if (tree[n].Freq != 0) {
2730 s->heap[++(s->heap_len)] = max_code = n;
2731 s->depth[n] = 0;
2732 } else {
2733 tree[n].Len = 0;
2734 }
2735 }
2736
2737 /* The pkzip format requires that at least one distance code exists,
2738 * and that at least one bit should be sent even if there is only one
2739 * possible code. So to avoid special checks later on we force at least
2740 * two codes of non zero frequency.
2741 */
2742 while (s->heap_len < 2) {
2743 node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0);
2744 tree[node].Freq = 1;
2745 s->depth[node] = 0;
2746 s->opt_len--; if (stree) s->static_len -= stree[node].Len;
2747 /* node is 0 or 1 so it does not have extra bits */
2748 }
2749 desc->max_code = max_code;
2750
2751 /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
2752 * establish sub-heaps of increasing lengths:
2753 */
2754 for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n);
2755
2756 /* Construct the Huffman tree by repeatedly combining the least two
2757 * frequent nodes.
2758 */
2759 node = elems; /* next internal node of the tree */
2760 do {
2761 pqremove(s, tree, n); /* n = node of least frequency */
2762 m = s->heap[SMALLEST]; /* m = node of next least frequency */
2763
2764 s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */
2765 s->heap[--(s->heap_max)] = m;
2766
2767 /* Create a new node father of n and m */
2768 tree[node].Freq = tree[n].Freq + tree[m].Freq;
2769 s->depth[node] = (uch) (MAX(s->depth[n], s->depth[m]) + 1);
2770 tree[n].Dad = tree[m].Dad = (ush)node;
2771 #ifdef DUMP_BL_TREE
2772 if (tree == s->bl_tree) {
2773 fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)",
2774 node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq);
2775 }
2776 #endif
2777 /* and insert the new node in the heap */
2778 s->heap[SMALLEST] = node++;
2779 pqdownheap(s, tree, SMALLEST);
2780
2781 } while (s->heap_len >= 2);
2782
2783 s->heap[--(s->heap_max)] = s->heap[SMALLEST];
2784
2785 /* At this point, the fields freq and dad are set. We can now
2786 * generate the bit lengths.
2787 */
2788 gen_bitlen(s, (tree_desc *)desc);
2789
2790 /* The field len is now set, we can generate the bit codes */
2791 gen_codes ((ct_data *)tree, max_code, s->bl_count);
2792 }
2793
2794 /* ===========================================================================
2795 * Scan a literal or distance tree to determine the frequencies of the codes
2796 * in the bit length tree.
2797 */
scan_tree(deflate_state * s,ct_data * tree,int max_code)2798 local void scan_tree (deflate_state *s,
2799 ct_data *tree, /* the tree to be scanned */
2800 int max_code) /* and its largest code of non zero frequency */
2801 {
2802 int n; /* iterates over all tree elements */
2803 int prevlen = -1; /* last emitted length */
2804 int curlen; /* length of current code */
2805 int nextlen = tree[0].Len; /* length of next code */
2806 int count = 0; /* repeat count of the current code */
2807 int max_count = 7; /* max repeat count */
2808 int min_count = 4; /* min repeat count */
2809
2810 if (nextlen == 0) max_count = 138, min_count = 3;
2811 tree[max_code+1].Len = (ush)0xffff; /* guard */
2812
2813 for (n = 0; n <= max_code; n++) {
2814 curlen = nextlen; nextlen = tree[n+1].Len;
2815 if (++count < max_count && curlen == nextlen) {
2816 continue;
2817 } else if (count < min_count) {
2818 s->bl_tree[curlen].Freq += count;
2819 } else if (curlen != 0) {
2820 if (curlen != prevlen) s->bl_tree[curlen].Freq++;
2821 s->bl_tree[REP_3_6].Freq++;
2822 } else if (count <= 10) {
2823 s->bl_tree[REPZ_3_10].Freq++;
2824 } else {
2825 s->bl_tree[REPZ_11_138].Freq++;
2826 }
2827 count = 0; prevlen = curlen;
2828 if (nextlen == 0) {
2829 max_count = 138, min_count = 3;
2830 } else if (curlen == nextlen) {
2831 max_count = 6, min_count = 3;
2832 } else {
2833 max_count = 7, min_count = 4;
2834 }
2835 }
2836 }
2837
2838 /* ===========================================================================
2839 * Send a literal or distance tree in compressed form, using the codes in
2840 * bl_tree.
2841 */
send_tree(deflate_state * s,ct_data * tree,int max_code)2842 local void send_tree (deflate_state *s,
2843 ct_data *tree, /* the tree to be scanned */
2844 int max_code) /* and its largest code of non zero frequency */
2845 {
2846 int n; /* iterates over all tree elements */
2847 int prevlen = -1; /* last emitted length */
2848 int curlen; /* length of current code */
2849 int nextlen = tree[0].Len; /* length of next code */
2850 int count = 0; /* repeat count of the current code */
2851 int max_count = 7; /* max repeat count */
2852 int min_count = 4; /* min repeat count */
2853
2854 /* tree[max_code+1].Len = -1; */ /* guard already set */
2855 if (nextlen == 0) max_count = 138, min_count = 3;
2856
2857 for (n = 0; n <= max_code; n++) {
2858 curlen = nextlen; nextlen = tree[n+1].Len;
2859 if (++count < max_count && curlen == nextlen) {
2860 continue;
2861 } else if (count < min_count) {
2862 do { send_code(s, curlen, s->bl_tree); } while (--count != 0);
2863
2864 } else if (curlen != 0) {
2865 if (curlen != prevlen) {
2866 send_code(s, curlen, s->bl_tree); count--;
2867 }
2868 Assert(count >= 3 && count <= 6, " 3_6?");
2869 send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2);
2870
2871 } else if (count <= 10) {
2872 send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3);
2873
2874 } else {
2875 send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7);
2876 }
2877 count = 0; prevlen = curlen;
2878 if (nextlen == 0) {
2879 max_count = 138, min_count = 3;
2880 } else if (curlen == nextlen) {
2881 max_count = 6, min_count = 3;
2882 } else {
2883 max_count = 7, min_count = 4;
2884 }
2885 }
2886 }
2887
2888 /* ===========================================================================
2889 * Construct the Huffman tree for the bit lengths and return the index in
2890 * bl_order of the last bit length code to send.
2891 */
build_bl_tree(deflate_state * s)2892 local int build_bl_tree(deflate_state *s)
2893 {
2894 int max_blindex; /* index of last bit length code of non zero freq */
2895
2896 /* Determine the bit length frequencies for literal and distance trees */
2897 scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code);
2898 scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code);
2899
2900 /* Build the bit length tree: */
2901 build_tree(s, (tree_desc *)(&(s->bl_desc)));
2902 /* opt_len now includes the length of the tree representations, except
2903 * the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
2904 */
2905
2906 /* Determine the number of bit length codes to send. The pkzip format
2907 * requires that at least 4 bit length codes be sent. (appnote.txt says
2908 * 3 but the actual value used is 4.)
2909 */
2910 for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) {
2911 if (s->bl_tree[bl_order[max_blindex]].Len != 0) break;
2912 }
2913 /* Update opt_len to include the bit length tree and counts */
2914 s->opt_len += 3*(max_blindex+1) + 5+5+4;
2915 Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld",
2916 s->opt_len, s->static_len));
2917
2918 return max_blindex;
2919 }
2920
2921 /* ===========================================================================
2922 * Send the header for a block using dynamic Huffman trees: the counts, the
2923 * lengths of the bit length codes, the literal tree and the distance tree.
2924 * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
2925 */
send_all_trees(deflate_state * s,int lcodes,int dcodes,int blcodes)2926 local void send_all_trees(deflate_state *s,
2927 int lcodes, int dcodes, int blcodes) /* number of codes for each tree */
2928 {
2929 int rank; /* index in bl_order */
2930
2931 Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
2932 Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
2933 "too many codes");
2934 Tracev((stderr, "\nbl counts: "));
2935 send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */
2936 send_bits(s, dcodes-1, 5);
2937 send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */
2938 for (rank = 0; rank < blcodes; rank++) {
2939 Tracev((stderr, "\nbl code %2d ", bl_order[rank]));
2940 send_bits(s, s->bl_tree[bl_order[rank]].Len, 3);
2941 }
2942 Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent));
2943
2944 send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */
2945 Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent));
2946
2947 send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */
2948 Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent));
2949 }
2950
2951 /* ===========================================================================
2952 * Send a stored block
2953 */
_tr_stored_block(deflate_state * s,charf * buf,ulg stored_len,int eof)2954 void _tr_stored_block(deflate_state *s,
2955 charf *buf, /* input block */
2956 ulg stored_len, /* length of input block */
2957 int eof) /* true if this is the last block for a file */
2958 {
2959 send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */
2960 #ifdef DEBUG_ZLIB
2961 s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L;
2962 s->compressed_len += (stored_len + 4) << 3;
2963 #endif
2964 copy_block(s, buf, (unsigned)stored_len, 1); /* with header */
2965 }
2966
2967 /* Send just the `stored block' type code without any length bytes or data.
2968 */
_tr_stored_type_only(deflate_state * s)2969 void _tr_stored_type_only(deflate_state *s)
2970 {
2971 send_bits(s, (STORED_BLOCK << 1), 3);
2972 bi_windup(s);
2973 #ifdef DEBUG_ZLIB
2974 s->compressed_len = (s->compressed_len + 3) & ~7L;
2975 #endif
2976 }
2977
2978 /* ===========================================================================
2979 * Send one empty static block to give enough lookahead for inflate.
2980 * This takes 10 bits, of which 7 may remain in the bit buffer.
2981 * The current inflate code requires 9 bits of lookahead. If the
2982 * last two codes for the previous block (real code plus EOB) were coded
2983 * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode
2984 * the last real code. In this case we send two empty static blocks instead
2985 * of one. (There are no problems if the previous block is stored or fixed.)
2986 * To simplify the code, we assume the worst case of last real code encoded
2987 * on one bit only.
2988 */
_tr_align(deflate_state * s)2989 void _tr_align(deflate_state *s)
2990 {
2991 send_bits(s, STATIC_TREES<<1, 3);
2992 send_code(s, END_BLOCK, static_ltree);
2993 #ifdef DEBUG_ZLIB
2994 s->compressed_len += 10L; /* 3 for block type, 7 for EOB */
2995 #endif
2996 bi_flush(s);
2997 /* Of the 10 bits for the empty block, we have already sent
2998 * (10 - bi_valid) bits. The lookahead for the last real code (before
2999 * the EOB of the previous block) was thus at least one plus the length
3000 * of the EOB plus what we have just sent of the empty static block.
3001 */
3002 if (1 + s->last_eob_len + 10 - s->bi_valid < 9) {
3003 send_bits(s, STATIC_TREES<<1, 3);
3004 send_code(s, END_BLOCK, static_ltree);
3005 #ifdef DEBUG_ZLIB
3006 s->compressed_len += 10L;
3007 #endif
3008 bi_flush(s);
3009 }
3010 s->last_eob_len = 7;
3011 }
3012
3013 /* ===========================================================================
3014 * Determine the best encoding for the current block: dynamic trees, static
3015 * trees or store, and output the encoded block to the zip file.
3016 */
_tr_flush_block(deflate_state * s,charf * buf,ulg stored_len,int eof)3017 void _tr_flush_block(deflate_state *s,
3018 charf *buf, /* input block, or NULL if too old */
3019 ulg stored_len, /* length of input block */
3020 int eof) /* true if this is the last block for a file */
3021 {
3022 ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
3023 int max_blindex = 0; /* index of last bit length code of non zero freq */
3024
3025 /* Build the Huffman trees unless a stored block is forced */
3026 if (s->level > 0) {
3027
3028 /* Check if the file is ascii or binary */
3029 if (s->data_type == Z_UNKNOWN) set_data_type(s);
3030
3031 /* Construct the literal and distance trees */
3032 build_tree(s, (tree_desc *)(&(s->l_desc)));
3033 Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len,
3034 s->static_len));
3035
3036 build_tree(s, (tree_desc *)(&(s->d_desc)));
3037 Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len,
3038 s->static_len));
3039 /* At this point, opt_len and static_len are the total bit lengths of
3040 * the compressed block data, excluding the tree representations.
3041 */
3042
3043 /* Build the bit length tree for the above two trees, and get the index
3044 * in bl_order of the last bit length code to send.
3045 */
3046 max_blindex = build_bl_tree(s);
3047
3048 /* Determine the best encoding. Compute first the block length in bytes*/
3049 opt_lenb = (s->opt_len+3+7)>>3;
3050 static_lenb = (s->static_len+3+7)>>3;
3051
3052 Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
3053 opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
3054 s->last_lit));
3055
3056 if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
3057
3058 } else {
3059 Assert(buf != (char*)0, "lost buf");
3060 opt_lenb = static_lenb = stored_len + 5; /* force a stored block */
3061 }
3062
3063 #ifdef FORCE_STORED
3064 if (buf != (char*)0) { /* force stored block */
3065 #else
3066 if (stored_len+4 <= opt_lenb && buf != (char*)0) {
3067 /* 4: two words for the lengths */
3068 #endif
3069 /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
3070 * Otherwise we can't have processed more than WSIZE input bytes since
3071 * the last block flush, because compression would have been
3072 * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
3073 * transform a block into a stored block.
3074 */
3075 _tr_stored_block(s, buf, stored_len, eof);
3076
3077 #ifdef FORCE_STATIC
3078 } else if (static_lenb >= 0) { /* force static trees */
3079 #else
3080 } else if (static_lenb == opt_lenb) {
3081 #endif
3082 send_bits(s, (STATIC_TREES<<1)+eof, 3);
3083 compress_block(s, (const ct_data *)static_ltree, (const ct_data *)static_dtree);
3084 #ifdef DEBUG_ZLIB
3085 s->compressed_len += 3 + s->static_len;
3086 #endif
3087 } else {
3088 send_bits(s, (DYN_TREES<<1)+eof, 3);
3089 send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1,
3090 max_blindex+1);
3091 compress_block(s, (const ct_data *)s->dyn_ltree, (const ct_data *)s->dyn_dtree);
3092 #ifdef DEBUG_ZLIB
3093 s->compressed_len += 3 + s->opt_len;
3094 #endif
3095 }
3096 Assert (s->compressed_len == s->bits_sent, "bad compressed size");
3097 /* The above check is made mod 2^32, for files larger than 512 MB
3098 * and uLong implemented on 32 bits.
3099 */
3100 init_block(s);
3101
3102 if (eof) {
3103 bi_windup(s);
3104 #ifdef DEBUG_ZLIB
3105 s->compressed_len += 7; /* align on byte boundary */
3106 #endif
3107 }
3108 Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3,
3109 s->compressed_len-7*eof));
3110 }
3111
3112 /* ===========================================================================
3113 * Save the match info and tally the frequency counts. Return true if
3114 * the current block must be flushed.
3115 */
3116 #if 0
3117 int _tr_tally (deflate_state *s,
3118 unsigned dist, /* distance of matched string */
3119 unsigned lc) /* match length-MIN_MATCH or unmatched char (if dist==0) */
3120 {
3121 s->d_buf[s->last_lit] = (ush)dist;
3122 s->l_buf[s->last_lit++] = (uch)lc;
3123 if (dist == 0) {
3124 /* lc is the unmatched char */
3125 s->dyn_ltree[lc].Freq++;
3126 } else {
3127 s->matches++;
3128 /* Here, lc is the match length - MIN_MATCH */
3129 dist--; /* dist = match distance - 1 */
3130 Assert((ush)dist < (ush)MAX_DIST(s) &&
3131 (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
3132 (ush)d_code(dist) < (ush)D_CODES, "_tr_tally: bad match");
3133
3134 s->dyn_ltree[_length_code[lc]+LITERALS+1].Freq++;
3135 s->dyn_dtree[d_code(dist)].Freq++;
3136 }
3137
3138 #ifdef TRUNCATE_BLOCK
3139 /* Try to guess if it is profitable to stop the current block here */
3140 if ((s->last_lit & 0x1fff) == 0 && s->level > 2) {
3141 /* Compute an upper bound for the compressed length */
3142 ulg out_length = (ulg)s->last_lit*8L;
3143 ulg in_length = (ulg)((long)s->strstart - s->block_start);
3144 int dcode;
3145 for (dcode = 0; dcode < D_CODES; dcode++) {
3146 out_length += (ulg)s->dyn_dtree[dcode].Freq *
3147 (5L+extra_dbits[dcode]);
3148 }
3149 out_length >>= 3;
3150 Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ",
3151 s->last_lit, in_length, out_length,
3152 100L - out_length*100L/in_length));
3153 if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1;
3154 }
3155 #endif
3156 return (s->last_lit == s->lit_bufsize-1);
3157 /* We avoid equality with lit_bufsize because of wraparound at 64K
3158 * on 16 bit machines and because stored blocks are restricted to
3159 * 64K-1 bytes.
3160 */
3161 }
3162 #endif
3163
3164 /* ===========================================================================
3165 * Send the block data compressed using the given Huffman trees
3166 */
3167 local void compress_block(deflate_state *s,
3168 const ct_data *ltree, /* literal tree */
3169 const ct_data *dtree) /* distance tree */
3170 {
3171 unsigned dist; /* distance of matched string */
3172 int lc; /* match length or unmatched char (if dist == 0) */
3173 unsigned lx = 0; /* running index in l_buf */
3174 unsigned code; /* the code to send */
3175 int extra; /* number of extra bits to send */
3176
3177 if (s->last_lit != 0) do {
3178 dist = s->d_buf[lx];
3179 lc = s->l_buf[lx++];
3180 if (dist == 0) {
3181 send_code(s, lc, ltree); /* send a literal byte */
3182 Tracecv(isgraph(lc), (stderr," '%c' ", lc));
3183 } else {
3184 /* Here, lc is the match length - MIN_MATCH */
3185 code = _length_code[lc];
3186 send_code(s, code+LITERALS+1, ltree); /* send the length code */
3187 extra = extra_lbits[code];
3188 if (extra != 0) {
3189 lc -= base_length[code];
3190 send_bits(s, lc, extra); /* send the extra length bits */
3191 }
3192 dist--; /* dist is now the match distance - 1 */
3193 code = d_code(dist);
3194 Assert (code < D_CODES, "bad d_code");
3195
3196 send_code(s, code, dtree); /* send the distance code */
3197 extra = extra_dbits[code];
3198 if (extra != 0) {
3199 dist -= base_dist[code];
3200 send_bits(s, dist, extra); /* send the extra distance bits */
3201 }
3202 } /* literal or match pair ? */
3203
3204 /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */
3205 Assert(s->pending < s->lit_bufsize + 2*lx, "pendingBuf overflow");
3206
3207 } while (lx < s->last_lit);
3208
3209 send_code(s, END_BLOCK, ltree);
3210 s->last_eob_len = ltree[END_BLOCK].Len;
3211 }
3212
3213 /* ===========================================================================
3214 * Set the data type to ASCII or BINARY, using a crude approximation:
3215 * binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise.
3216 * IN assertion: the fields freq of dyn_ltree are set and the total of all
3217 * frequencies does not exceed 64K (to fit in an int on 16 bit machines).
3218 */
3219 local void set_data_type(deflate_state *s)
3220 {
3221 int n = 0;
3222 unsigned ascii_freq = 0;
3223 unsigned bin_freq = 0;
3224 while (n < 7) bin_freq += s->dyn_ltree[n++].Freq;
3225 while (n < 128) ascii_freq += s->dyn_ltree[n++].Freq;
3226 while (n < LITERALS) bin_freq += s->dyn_ltree[n++].Freq;
3227 s->data_type = (Byte)(bin_freq > (ascii_freq >> 2) ? Z_BINARY : Z_ASCII);
3228 }
3229
3230 /* ===========================================================================
3231 * Reverse the first len bits of a code, using straightforward code (a faster
3232 * method would use a table)
3233 * IN assertion: 1 <= len <= 15
3234 */
3235 local unsigned bi_reverse(unsigned code, /* the value to invert */
3236 int len) /* its bit length */
3237 {
3238 unsigned res = 0;
3239 do {
3240 res |= code & 1;
3241 code >>= 1, res <<= 1;
3242 } while (--len > 0);
3243 return res >> 1;
3244 }
3245
3246 /* ===========================================================================
3247 * Flush the bit buffer, keeping at most 7 bits in it.
3248 */
3249 local void bi_flush(deflate_state *s)
3250 {
3251 if (s->bi_valid == 16) {
3252 put_short(s, s->bi_buf);
3253 s->bi_buf = 0;
3254 s->bi_valid = 0;
3255 } else if (s->bi_valid >= 8) {
3256 put_byte(s, (Byte)s->bi_buf);
3257 s->bi_buf >>= 8;
3258 s->bi_valid -= 8;
3259 }
3260 }
3261
3262 /* ===========================================================================
3263 * Flush the bit buffer and align the output on a byte boundary
3264 */
3265 local void bi_windup(deflate_state *s)
3266 {
3267 if (s->bi_valid > 8) {
3268 put_short(s, s->bi_buf);
3269 } else if (s->bi_valid > 0) {
3270 put_byte(s, (Byte)s->bi_buf);
3271 }
3272 s->bi_buf = 0;
3273 s->bi_valid = 0;
3274 #ifdef DEBUG_ZLIB
3275 s->bits_sent = (s->bits_sent+7) & ~7;
3276 #endif
3277 }
3278
3279 /* ===========================================================================
3280 * Copy a stored block, storing first the length and its
3281 * one's complement if requested.
3282 */
3283 local void copy_block(deflate_state *s,
3284 charf *buf, /* the input data */
3285 unsigned len, /* its length */
3286 int header) /* true if block header must be written */
3287 {
3288 bi_windup(s); /* align on byte boundary */
3289 s->last_eob_len = 8; /* enough lookahead for inflate */
3290
3291 if (header) {
3292 put_short(s, (ush)len);
3293 put_short(s, (ush)~len);
3294 #ifdef DEBUG_ZLIB
3295 s->bits_sent += 2*16;
3296 #endif
3297 }
3298 #ifdef DEBUG_ZLIB
3299 s->bits_sent += (ulg)len<<3;
3300 #endif
3301 /* bundle up the put_byte(s, *buf++) calls */
3302 zmemcpy(&s->pending_buf[s->pending], buf, len);
3303 s->pending += len;
3304 }
3305 /* --- trees.c */
3306
3307 /* +++ inflate.c */
3308
3309 /* inflate.c -- zlib interface to inflate modules
3310 * Copyright (C) 1995-2002 Mark Adler
3311 * For conditions of distribution and use, see copyright notice in zlib.h
3312 */
3313
3314 /* #include "zutil.h" */
3315
3316 /* +++ infblock.h */
3317
3318 /* infblock.h -- header to use infblock.c
3319 * Copyright (C) 1995-2002 Mark Adler
3320 * For conditions of distribution and use, see copyright notice in zlib.h
3321 */
3322
3323 /* WARNING: this file should *not* be used by applications. It is
3324 part of the implementation of the compression library and is
3325 subject to change. Applications should only use zlib.h.
3326 */
3327
3328 struct inflate_blocks_state;
3329 typedef struct inflate_blocks_state FAR inflate_blocks_statef;
3330
3331 extern inflate_blocks_statef * inflate_blocks_new(
3332 z_streamp z,
3333 check_func c, /* check function */
3334 uInt w); /* window size */
3335
3336 extern int inflate_blocks(
3337 inflate_blocks_statef *,
3338 z_streamp ,
3339 int); /* initial return code */
3340
3341 extern void inflate_blocks_reset(
3342 inflate_blocks_statef *,
3343 z_streamp ,
3344 uLongf *); /* check value on output */
3345
3346 extern int inflate_blocks_free(
3347 inflate_blocks_statef *,
3348 z_streamp);
3349
3350 extern void inflate_set_dictionary(
3351 inflate_blocks_statef *s,
3352 const Bytef *d, /* dictionary */
3353 uInt n); /* dictionary length */
3354
3355 extern int inflate_blocks_sync_point(
3356 inflate_blocks_statef *s);
3357 extern int inflate_addhistory(
3358 inflate_blocks_statef *,
3359 z_streamp);
3360
3361 extern int inflate_packet_flush(
3362 inflate_blocks_statef *);
3363
3364 /* --- infblock.h */
3365
3366 #ifndef NO_DUMMY_DECL
3367 struct inflate_blocks_state {int dummy;}; /* for buggy compilers */
3368 #endif
3369
3370 typedef enum {
3371 METHOD, /* waiting for method byte */
3372 FLAG, /* waiting for flag byte */
3373 DICT4, /* four dictionary check bytes to go */
3374 DICT3, /* three dictionary check bytes to go */
3375 DICT2, /* two dictionary check bytes to go */
3376 DICT1, /* one dictionary check byte to go */
3377 DICT0, /* waiting for inflateSetDictionary */
3378 BLOCKS, /* decompressing blocks */
3379 CHECK4, /* four check bytes to go */
3380 CHECK3, /* three check bytes to go */
3381 CHECK2, /* two check bytes to go */
3382 CHECK1, /* one check byte to go */
3383 DONE, /* finished check, done */
3384 BAD} /* got an error--stay here */
3385 inflate_mode;
3386
3387 /* inflate private state */
3388 struct internal_state {
3389
3390 /* mode */
3391 inflate_mode mode; /* current inflate mode */
3392
3393 /* mode dependent information */
3394 union {
3395 uInt method; /* if FLAGS, method byte */
3396 struct {
3397 uLong was; /* computed check value */
3398 uLong need; /* stream check value */
3399 } check; /* if CHECK, check values to compare */
3400 uInt marker; /* if BAD, inflateSync's marker bytes count */
3401 } sub; /* submode */
3402
3403 /* mode independent information */
3404 int nowrap; /* flag for no wrapper */
3405 uInt wbits; /* log2(window size) (8..15, defaults to 15) */
3406 inflate_blocks_statef
3407 *blocks; /* current inflate_blocks state */
3408
3409 };
3410
3411
3412 int ZEXPORT inflateReset(z_streamp z)
3413 {
3414 if (z == Z_NULL || z->state == Z_NULL)
3415 return Z_STREAM_ERROR;
3416 z->total_in = z->total_out = 0;
3417 z->msg = Z_NULL;
3418 z->state->mode = z->state->nowrap ? BLOCKS : METHOD;
3419 inflate_blocks_reset(z->state->blocks, z, Z_NULL);
3420 Tracev((stderr, "inflate: reset\n"));
3421 return Z_OK;
3422 }
3423
3424
3425 int ZEXPORT inflateEnd(z_streamp z)
3426 {
3427 if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL)
3428 return Z_STREAM_ERROR;
3429 if (z->state->blocks != Z_NULL)
3430 inflate_blocks_free(z->state->blocks, z);
3431 ZFREE(z, z->state);
3432 z->state = Z_NULL;
3433 Tracev((stderr, "inflate: end\n"));
3434 return Z_OK;
3435 }
3436
3437
3438 int ZEXPORT inflateInit2_(z_streamp z, int w, const char *vers, int stream_size)
3439 {
3440 if (vers == Z_NULL || vers[0] != ZLIB_VERSION[0] ||
3441 stream_size != sizeof(z_stream))
3442 return Z_VERSION_ERROR;
3443
3444 /* initialize state */
3445 if (z == Z_NULL)
3446 return Z_STREAM_ERROR;
3447 z->msg = Z_NULL;
3448 #ifndef NO_ZCFUNCS
3449 if (z->zalloc == Z_NULL)
3450 {
3451 z->zalloc = zcalloc;
3452 z->opaque = (voidpf)0;
3453 }
3454 if (z->zfree == Z_NULL) z->zfree = zcfree;
3455 #endif
3456 if ((z->state = (struct internal_state FAR *)
3457 ZALLOC(z,1,sizeof(struct internal_state))) == Z_NULL)
3458 return Z_MEM_ERROR;
3459 z->state->blocks = Z_NULL;
3460
3461 /* handle undocumented nowrap option (no zlib header or check) */
3462 z->state->nowrap = 0;
3463 if (w < 0)
3464 {
3465 w = - w;
3466 z->state->nowrap = 1;
3467 }
3468
3469 /* set window size */
3470 if (w < 8 || w > 15)
3471 {
3472 inflateEnd(z);
3473 return Z_STREAM_ERROR;
3474 }
3475 z->state->wbits = (uInt)w;
3476
3477 /* create inflate_blocks state */
3478 if ((z->state->blocks =
3479 inflate_blocks_new(z, z->state->nowrap ? Z_NULL : adler32, (uInt)1 << w))
3480 == Z_NULL)
3481 {
3482 inflateEnd(z);
3483 return Z_MEM_ERROR;
3484 }
3485 Tracev((stderr, "inflate: allocated\n"));
3486
3487 /* reset state */
3488 inflateReset(z);
3489 return Z_OK;
3490 }
3491
3492
3493 #if 0
3494 int ZEXPORT inflateInit_(z_streamp z, const char *vers, int stream_size)
3495 {
3496 return inflateInit2_(z, DEF_WBITS, vers, stream_size);
3497 }
3498 #endif
3499
3500
3501 #define NEEDBYTE {if(z->avail_in==0)goto empty;r=Z_OK;}
3502 #define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++)
3503
3504 int ZEXPORT inflate(z_streamp z, int f)
3505 {
3506 int r, r2;
3507 uInt b;
3508
3509 if (z == Z_NULL || z->state == Z_NULL || z->next_in == Z_NULL)
3510 return Z_STREAM_ERROR;
3511 r2 = f == Z_FINISH ? Z_BUF_ERROR : Z_OK;
3512 r = Z_BUF_ERROR;
3513 while (1) switch (z->state->mode)
3514 {
3515 case METHOD:
3516 NEEDBYTE
3517 if (((z->state->sub.method = NEXTBYTE) & 0xf) != Z_DEFLATED)
3518 {
3519 z->state->mode = BAD;
3520 z->msg = "unknown compression method";
3521 z->state->sub.marker = 5; /* can't try inflateSync */
3522 break;
3523 }
3524 if ((z->state->sub.method >> 4) + 8 > z->state->wbits)
3525 {
3526 z->state->mode = BAD;
3527 z->msg = "invalid window size";
3528 z->state->sub.marker = 5; /* can't try inflateSync */
3529 break;
3530 }
3531 z->state->mode = FLAG;
3532 /* FALLTHROUGH */
3533 case FLAG:
3534 NEEDBYTE
3535 b = NEXTBYTE;
3536 if (((z->state->sub.method << 8) + b) % 31)
3537 {
3538 z->state->mode = BAD;
3539 z->msg = "incorrect header check";
3540 z->state->sub.marker = 5; /* can't try inflateSync */
3541 break;
3542 }
3543 Tracev((stderr, "inflate: zlib header ok\n"));
3544 if (!(b & PRESET_DICT))
3545 {
3546 z->state->mode = BLOCKS;
3547 break;
3548 }
3549 z->state->mode = DICT4;
3550 /* FALLTHROUGH */
3551 case DICT4:
3552 NEEDBYTE
3553 z->state->sub.check.need = (uLong)NEXTBYTE << 24;
3554 z->state->mode = DICT3;
3555 /* FALLTHROUGH */
3556 case DICT3:
3557 NEEDBYTE
3558 z->state->sub.check.need += (uLong)NEXTBYTE << 16;
3559 z->state->mode = DICT2;
3560 /* FALLTHROUGH */
3561 case DICT2:
3562 NEEDBYTE
3563 z->state->sub.check.need += (uLong)NEXTBYTE << 8;
3564 z->state->mode = DICT1;
3565 /* FALLTHROUGH */
3566 case DICT1:
3567 NEEDBYTE
3568 z->state->sub.check.need += (uLong)NEXTBYTE;
3569 z->adler = z->state->sub.check.need;
3570 z->state->mode = DICT0;
3571 return Z_NEED_DICT;
3572 case DICT0:
3573 z->state->mode = BAD;
3574 z->msg = "need dictionary";
3575 z->state->sub.marker = 0; /* can try inflateSync */
3576 return Z_STREAM_ERROR;
3577 case BLOCKS:
3578 r = inflate_blocks(z->state->blocks, z, r);
3579 if (f == Z_PACKET_FLUSH && z->avail_in == 0 && z->avail_out != 0)
3580 r = inflate_packet_flush(z->state->blocks);
3581 if (r == Z_DATA_ERROR)
3582 {
3583 z->state->mode = BAD;
3584 z->state->sub.marker = 0; /* can try inflateSync */
3585 break;
3586 }
3587 if (r == Z_OK)
3588 r = r2;
3589 if (r != Z_STREAM_END)
3590 return r;
3591 r = r2;
3592 inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was);
3593 if (z->state->nowrap)
3594 {
3595 z->state->mode = DONE;
3596 break;
3597 }
3598 z->state->mode = CHECK4;
3599 /* FALLTHROUGH */
3600 case CHECK4:
3601 NEEDBYTE
3602 z->state->sub.check.need = (uLong)NEXTBYTE << 24;
3603 z->state->mode = CHECK3;
3604 /* FALLTHROUGH */
3605 case CHECK3:
3606 NEEDBYTE
3607 z->state->sub.check.need += (uLong)NEXTBYTE << 16;
3608 z->state->mode = CHECK2;
3609 /* FALLTHROUGH */
3610 case CHECK2:
3611 NEEDBYTE
3612 z->state->sub.check.need += (uLong)NEXTBYTE << 8;
3613 z->state->mode = CHECK1;
3614 /* FALLTHROUGH */
3615 case CHECK1:
3616 NEEDBYTE
3617 z->state->sub.check.need += (uLong)NEXTBYTE;
3618
3619 if (z->state->sub.check.was != z->state->sub.check.need)
3620 {
3621 z->state->mode = BAD;
3622 z->msg = "incorrect data check";
3623 z->state->sub.marker = 5; /* can't try inflateSync */
3624 break;
3625 }
3626 Tracev((stderr, "inflate: zlib check ok\n"));
3627 z->state->mode = DONE;
3628 /* FALLTHROUGH */
3629 case DONE:
3630 return Z_STREAM_END;
3631 case BAD:
3632 return Z_DATA_ERROR;
3633 default:
3634 return Z_STREAM_ERROR;
3635 }
3636 empty:
3637 if (f != Z_PACKET_FLUSH)
3638 return r;
3639 z->state->mode = BAD;
3640 z->msg = "need more for packet flush";
3641 z->state->sub.marker = 0;
3642 return Z_DATA_ERROR;
3643 }
3644
3645
3646 #if 0
3647 int ZEXPORT inflateSetDictionary(z_streamp z,
3648 const Bytef *dictionary,
3649 uInt dictLength)
3650 {
3651 uInt length = dictLength;
3652
3653 if (z == Z_NULL || z->state == Z_NULL || z->state->mode != DICT0)
3654 return Z_STREAM_ERROR;
3655
3656 if (adler32(1L, dictionary, dictLength) != z->adler) return Z_DATA_ERROR;
3657 z->adler = 1L;
3658
3659 if (length >= ((uInt)1<<z->state->wbits))
3660 {
3661 length = (1<<z->state->wbits)-1;
3662 dictionary += dictLength - length;
3663 }
3664 inflate_set_dictionary(z->state->blocks, dictionary, length);
3665 z->state->mode = BLOCKS;
3666 return Z_OK;
3667 }
3668 #endif
3669
3670 /*
3671 * This subroutine adds the data at next_in/avail_in to the output history
3672 * without performing any output. The output buffer must be "caught up";
3673 * i.e. no pending output (hence s->read equals s->write), and the state must
3674 * be BLOCKS (i.e. we should be willing to see the start of a series of
3675 * BLOCKS). On exit, the output will also be caught up, and the checksum
3676 * will have been updated if need be.
3677 */
3678
3679 int inflateIncomp(z_stream *z)
3680 {
3681 if (z->state->mode != BLOCKS)
3682 return Z_DATA_ERROR;
3683 return inflate_addhistory(z->state->blocks, z);
3684 }
3685
3686 #if 0
3687 int ZEXPORT inflateSync(z)
3688 z_streamp z;
3689 {
3690 uInt n; /* number of bytes to look at */
3691 Bytef *p; /* pointer to bytes */
3692 uInt m; /* number of marker bytes found in a row */
3693 uLong r, w; /* temporaries to save total_in and total_out */
3694
3695 /* set up */
3696 if (z == Z_NULL || z->state == Z_NULL)
3697 return Z_STREAM_ERROR;
3698 if (z->state->mode != BAD)
3699 {
3700 z->state->mode = BAD;
3701 z->state->sub.marker = 0;
3702 }
3703 if ((n = z->avail_in) == 0)
3704 return Z_BUF_ERROR;
3705 p = z->next_in;
3706 m = z->state->sub.marker;
3707
3708 /* search */
3709 while (n && m < 4)
3710 {
3711 static const Byte mark[4] = {0, 0, 0xff, 0xff};
3712 if (*p == mark[m])
3713 m++;
3714 else if (*p)
3715 m = 0;
3716 else
3717 m = 4 - m;
3718 p++, n--;
3719 }
3720
3721 /* restore */
3722 z->total_in += p - z->next_in;
3723 z->next_in = p;
3724 z->avail_in = n;
3725 z->state->sub.marker = m;
3726
3727 /* return no joy or set up to restart on a new block */
3728 if (m != 4)
3729 return Z_DATA_ERROR;
3730 r = z->total_in; w = z->total_out;
3731 inflateReset(z);
3732 z->total_in = r; z->total_out = w;
3733 z->state->mode = BLOCKS;
3734 return Z_OK;
3735 }
3736 #endif
3737
3738
3739 /* Returns true if inflate is currently at the end of a block generated
3740 * by Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
3741 * implementation to provide an additional safety check. PPP uses Z_SYNC_FLUSH
3742 * but removes the length bytes of the resulting empty stored block. When
3743 * decompressing, PPP checks that at the end of input packet, inflate is
3744 * waiting for these length bytes.
3745 */
3746 #if 0
3747 int ZEXPORT inflateSyncPoint(z)
3748 z_streamp z;
3749 {
3750 if (z == Z_NULL || z->state == Z_NULL || z->state->blocks == Z_NULL)
3751 return Z_STREAM_ERROR;
3752 return inflate_blocks_sync_point(z->state->blocks);
3753 }
3754 #endif
3755 #undef NEEDBYTE
3756 #undef NEXTBYTE
3757 /* --- inflate.c */
3758
3759 /* +++ infblock.c */
3760
3761 /* infblock.c -- interpret and process block types to last block
3762 * Copyright (C) 1995-2002 Mark Adler
3763 * For conditions of distribution and use, see copyright notice in zlib.h
3764 */
3765
3766 /* #include "zutil.h" */
3767 /* #include "infblock.h" */
3768
3769 /* +++ inftrees.h */
3770
3771 /* inftrees.h -- header to use inftrees.c
3772 * Copyright (C) 1995-2002 Mark Adler
3773 * For conditions of distribution and use, see copyright notice in zlib.h
3774 */
3775
3776 /* WARNING: this file should *not* be used by applications. It is
3777 part of the implementation of the compression library and is
3778 subject to change. Applications should only use zlib.h.
3779 */
3780
3781 /* Huffman code lookup table entry--this entry is four bytes for machines
3782 that have 16-bit pointers (e.g. PC's in the small or medium model). */
3783
3784 typedef struct inflate_huft_s FAR inflate_huft;
3785
3786 struct inflate_huft_s {
3787 union {
3788 struct {
3789 Byte Exop; /* number of extra bits or operation */
3790 Byte Bits; /* number of bits in this code or subcode */
3791 } what;
3792 uInt pad; /* pad structure to a power of 2 (4 bytes for */
3793 } word; /* 16-bit, 8 bytes for 32-bit int's) */
3794 uInt base; /* literal, length base, distance base,
3795 or table offset */
3796 };
3797
3798 /* Maximum size of dynamic tree. The maximum found in a long but non-
3799 exhaustive search was 1004 huft structures (850 for length/literals
3800 and 154 for distances, the latter actually the result of an
3801 exhaustive search). The actual maximum is not known, but the
3802 value below is more than safe. */
3803 #define MANY 1440
3804
3805 extern int inflate_trees_bits(
3806 uIntf *, /* 19 code lengths */
3807 uIntf *, /* bits tree desired/actual depth */
3808 inflate_huft * FAR *, /* bits tree result */
3809 inflate_huft *, /* space for trees */
3810 z_streamp); /* for messages */
3811
3812 extern int inflate_trees_dynamic(
3813 uInt, /* number of literal/length codes */
3814 uInt, /* number of distance codes */
3815 uIntf *, /* that many (total) code lengths */
3816 uIntf *, /* literal desired/actual bit depth */
3817 uIntf *, /* distance desired/actual bit depth */
3818 inflate_huft * FAR *, /* literal/length tree result */
3819 inflate_huft * FAR *, /* distance tree result */
3820 inflate_huft *, /* space for trees */
3821 z_streamp); /* for messages */
3822
3823 extern int inflate_trees_fixed(
3824 uIntf *, /* literal desired/actual bit depth */
3825 uIntf *, /* distance desired/actual bit depth */
3826 inflate_huft * FAR *, /* literal/length tree result */
3827 inflate_huft * FAR *, /* distance tree result */
3828 z_streamp); /* for memory allocation */
3829 /* --- inftrees.h */
3830
3831 /* +++ infcodes.h */
3832
3833 /* infcodes.h -- header to use infcodes.c
3834 * Copyright (C) 1995-2002 Mark Adler
3835 * For conditions of distribution and use, see copyright notice in zlib.h
3836 */
3837
3838 /* WARNING: this file should *not* be used by applications. It is
3839 part of the implementation of the compression library and is
3840 subject to change. Applications should only use zlib.h.
3841 */
3842
3843 struct inflate_codes_state;
3844 typedef struct inflate_codes_state FAR inflate_codes_statef;
3845
3846 extern inflate_codes_statef *inflate_codes_new(
3847 uInt, uInt,
3848 inflate_huft *, inflate_huft *,
3849 z_streamp );
3850
3851 extern int inflate_codes(
3852 inflate_blocks_statef *,
3853 z_streamp ,
3854 int);
3855
3856 extern void inflate_codes_free(
3857 inflate_codes_statef *,
3858 z_streamp );
3859
3860 /* --- infcodes.h */
3861
3862 /* +++ infutil.h */
3863
3864 /* infutil.h -- types and macros common to blocks and codes
3865 * Copyright (C) 1995-2002 Mark Adler
3866 * For conditions of distribution and use, see copyright notice in zlib.h
3867 */
3868
3869 /* WARNING: this file should *not* be used by applications. It is
3870 part of the implementation of the compression library and is
3871 subject to change. Applications should only use zlib.h.
3872 */
3873
3874 #ifndef _INFUTIL_H
3875 #define _INFUTIL_H
3876
3877 typedef enum {
3878 TYPE, /* get type bits (3, including end bit) */
3879 LENS, /* get lengths for stored */
3880 STORED, /* processing stored block */
3881 TABLE, /* get table lengths */
3882 BTREE, /* get bit lengths tree for a dynamic block */
3883 DTREE, /* get length, distance trees for a dynamic block */
3884 CODES, /* processing fixed or dynamic block */
3885 DRY, /* output remaining window bytes */
3886 DONEB, /* finished last block, done */
3887 BADB} /* got a data error--stuck here */
3888 inflate_block_mode;
3889
3890 /* inflate blocks semi-private state */
3891 struct inflate_blocks_state {
3892
3893 /* mode */
3894 inflate_block_mode mode; /* current inflate_block mode */
3895
3896 /* mode dependent information */
3897 union {
3898 uInt left; /* if STORED, bytes left to copy */
3899 struct {
3900 uInt table; /* table lengths (14 bits) */
3901 uInt index; /* index into blens (or border) */
3902 uIntf *blens; /* bit lengths of codes */
3903 uInt bb; /* bit length tree depth */
3904 inflate_huft *tb; /* bit length decoding tree */
3905 } trees; /* if DTREE, decoding info for trees */
3906 struct {
3907 inflate_codes_statef
3908 *codes;
3909 } decode; /* if CODES, current state */
3910 } sub; /* submode */
3911 uInt last; /* true if this block is the last block */
3912
3913 /* mode independent information */
3914 uInt bitk; /* bits in bit buffer */
3915 uLong bitb; /* bit buffer */
3916 inflate_huft *hufts; /* single malloc for tree space */
3917 Bytef *window; /* sliding window */
3918 Bytef *end; /* one byte after sliding window */
3919 Bytef *read; /* window read pointer */
3920 Bytef *write; /* window write pointer */
3921 check_func checkfn; /* check function */
3922 uLong check; /* check on output */
3923
3924 };
3925
3926
3927 /* defines for inflate input/output */
3928 /* update pointers and return */
3929 #define UPDBITS {s->bitb=b;s->bitk=k;}
3930 #define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;}
3931 #define UPDOUT {s->write=q;}
3932 #define UPDATE {UPDBITS UPDIN UPDOUT}
3933 #define LEAVE {UPDATE return inflate_flush(s,z,r);}
3934 /* get bytes and bits */
3935 #define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;}
3936 #define NEEDBYTE {if(n)r=Z_OK;else LEAVE}
3937 #define NEXTBYTE (n--,*p++)
3938 #define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}}
3939 #define DUMPBITS(j) {b>>=(j);k-=(j);}
3940 /* output bytes */
3941 #define WAVAIL (uInt)(q<s->read?s->read-q-1:s->end-q)
3942 #define LOADOUT {q=s->write;m=(uInt)WAVAIL;}
3943 #define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}}
3944 #define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT}
3945 #define NEEDOUT {if(m==0){WRAP if(m==0){FLUSH WRAP if(m==0) LEAVE}}r=Z_OK;}
3946 #define OUTBYTE(a) {*q++=(Byte)(a);m--;}
3947 /* load local pointers */
3948 #define LOAD {LOADIN LOADOUT}
3949
3950 /* masks for lower bits (size given to avoid silly warnings with Visual C++) */
3951 extern uInt inflate_mask[17];
3952
3953 /* copy as much as possible from the sliding window to the output area */
3954 extern int inflate_flush(
3955 inflate_blocks_statef *,
3956 z_streamp ,
3957 int);
3958
3959 #ifndef NO_DUMMY_DECL
3960 struct internal_state {int dummy;}; /* for buggy compilers */
3961 #endif
3962
3963 #endif
3964 /* --- infutil.h */
3965
3966 #ifndef NO_DUMMY_DECL
3967 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
3968 #endif
3969
3970 /* simplify the use of the inflate_huft type with some defines */
3971 #define exop word.what.Exop
3972 #define bits word.what.Bits
3973
3974 /* Table for deflate from PKZIP's appnote.txt. */
3975 local const uInt border[] = { /* Order of the bit length code lengths */
3976 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
3977
3978 /*
3979 Notes beyond the 1.93a appnote.txt:
3980
3981 1. Distance pointers never point before the beginning of the output
3982 stream.
3983 2. Distance pointers can point back across blocks, up to 32k away.
3984 3. There is an implied maximum of 7 bits for the bit length table and
3985 15 bits for the actual data.
3986 4. If only one code exists, then it is encoded using one bit. (Zero
3987 would be more efficient, but perhaps a little confusing.) If two
3988 codes exist, they are coded using one bit each (0 and 1).
3989 5. There is no way of sending zero distance codes--a dummy must be
3990 sent if there are none. (History: a pre 2.0 version of PKZIP would
3991 store blocks with no distance codes, but this was discovered to be
3992 too harsh a criterion.) Valid only for 1.93a. 2.04c does allow
3993 zero distance codes, which is sent as one code of zero bits in
3994 length.
3995 6. There are up to 286 literal/length codes. Code 256 represents the
3996 end-of-block. Note however that the static length tree defines
3997 288 codes just to fill out the Huffman codes. Codes 286 and 287
3998 cannot be used though, since there is no length base or extra bits
3999 defined for them. Similarly, there are up to 30 distance codes.
4000 However, static trees define 32 codes (all 5 bits) to fill out the
4001 Huffman codes, but the last two had better not show up in the data.
4002 7. Unzip can check dynamic Huffman blocks for complete code sets.
4003 The exception is that a single code would not be complete (see #4).
4004 8. The five bits following the block type is really the number of
4005 literal codes sent minus 257.
4006 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
4007 (1+6+6). Therefore, to output three times the length, you output
4008 three codes (1+1+1), whereas to output four times the same length,
4009 you only need two codes (1+3). Hmm.
4010 10. In the tree reconstruction algorithm, Code = Code + Increment
4011 only if BitLength(i) is not zero. (Pretty obvious.)
4012 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19)
4013 12. Note: length code 284 can represent 227-258, but length code 285
4014 really is 258. The last length deserves its own, short code
4015 since it gets used a lot in very redundant files. The length
4016 258 is special since 258 - 3 (the min match length) is 255.
4017 13. The literal/length and distance code bit lengths are read as a
4018 single stream of lengths. It is possible (and advantageous) for
4019 a repeat code (16, 17, or 18) to go across the boundary between
4020 the two sets of lengths.
4021 */
4022
4023
4024 void inflate_blocks_reset(inflate_blocks_statef *s, z_streamp z, uLongf *c)
4025 {
4026 if (c != Z_NULL)
4027 *c = s->check;
4028 if (s->mode == BTREE || s->mode == DTREE)
4029 ZFREE(z, s->sub.trees.blens);
4030 if (s->mode == CODES)
4031 inflate_codes_free(s->sub.decode.codes, z);
4032 s->mode = TYPE;
4033 s->bitk = 0;
4034 s->bitb = 0;
4035 s->read = s->write = s->window;
4036 if (s->checkfn != Z_NULL)
4037 z->adler = s->check = (*s->checkfn)(0L, (const Bytef *)Z_NULL, 0);
4038 Tracev((stderr, "inflate: blocks reset\n"));
4039 }
4040
4041
4042 inflate_blocks_statef *inflate_blocks_new(z_streamp z, check_func c, uInt w)
4043 {
4044 inflate_blocks_statef *s;
4045
4046 if ((s = (inflate_blocks_statef *)ZALLOC
4047 (z,1,sizeof(struct inflate_blocks_state))) == Z_NULL)
4048 return s;
4049 if ((s->hufts =
4050 (inflate_huft *)ZALLOC(z, sizeof(inflate_huft), MANY)) == Z_NULL)
4051 {
4052 ZFREE(z, s);
4053 return Z_NULL;
4054 }
4055 if ((s->window = (Bytef *)ZALLOC(z, 1, w)) == Z_NULL)
4056 {
4057 ZFREE(z, s->hufts);
4058 ZFREE(z, s);
4059 return Z_NULL;
4060 }
4061 s->end = s->window + w;
4062 s->checkfn = c;
4063 s->mode = TYPE;
4064 Tracev((stderr, "inflate: blocks allocated\n"));
4065 inflate_blocks_reset(s, z, Z_NULL);
4066 return s;
4067 }
4068
4069
4070 int inflate_blocks(inflate_blocks_statef *s, z_streamp z, int r)
4071 {
4072 uInt t; /* temporary storage */
4073 uLong b; /* bit buffer */
4074 uInt k; /* bits in bit buffer */
4075 Bytef *p; /* input data pointer */
4076 uInt n; /* bytes available there */
4077 Bytef *q; /* output window write pointer */
4078 uInt m; /* bytes to end of window or read pointer */
4079
4080 /* copy input/output information to locals (UPDATE macro restores) */
4081 LOAD
4082
4083 /* process input based on current state */
4084 while (1) switch (s->mode)
4085 {
4086 case TYPE:
4087 NEEDBITS(3)
4088 t = (uInt)b & 7;
4089 s->last = t & 1;
4090 switch (t >> 1)
4091 {
4092 case 0: /* stored */
4093 Tracev((stderr, "inflate: stored block%s\n",
4094 s->last ? " (last)" : ""));
4095 DUMPBITS(3)
4096 t = k & 7; /* go to byte boundary */
4097 DUMPBITS(t)
4098 s->mode = LENS; /* get length of stored block */
4099 break;
4100 case 1: /* fixed */
4101 Tracev((stderr, "inflate: fixed codes block%s\n",
4102 s->last ? " (last)" : ""));
4103 {
4104 uInt bl, bd;
4105 inflate_huft *tl, *td;
4106
4107 inflate_trees_fixed(&bl, &bd, &tl, &td, z);
4108 s->sub.decode.codes = inflate_codes_new(bl, bd, tl, td, z);
4109 if (s->sub.decode.codes == Z_NULL)
4110 {
4111 r = Z_MEM_ERROR;
4112 LEAVE
4113 }
4114 }
4115 DUMPBITS(3)
4116 s->mode = CODES;
4117 break;
4118 case 2: /* dynamic */
4119 Tracev((stderr, "inflate: dynamic codes block%s\n",
4120 s->last ? " (last)" : ""));
4121 DUMPBITS(3)
4122 s->mode = TABLE;
4123 break;
4124 case 3: /* illegal */
4125 DUMPBITS(3)
4126 s->mode = BADB;
4127 z->msg = "invalid block type";
4128 r = Z_DATA_ERROR;
4129 LEAVE
4130 }
4131 break;
4132 case LENS:
4133 NEEDBITS(32)
4134 if ((((~b) >> 16) & 0xffff) != (b & 0xffff))
4135 {
4136 s->mode = BADB;
4137 z->msg = "invalid stored block lengths";
4138 r = Z_DATA_ERROR;
4139 LEAVE
4140 }
4141 s->sub.left = (uInt)b & 0xffff;
4142 b = k = 0; /* dump bits */
4143 Tracev((stderr, "inflate: stored length %u\n", s->sub.left));
4144 s->mode = s->sub.left ? STORED : (s->last ? DRY : TYPE);
4145 break;
4146 case STORED:
4147 if (n == 0)
4148 LEAVE
4149 NEEDOUT
4150 t = s->sub.left;
4151 if (t > n) t = n;
4152 if (t > m) t = m;
4153 zmemcpy(q, p, t);
4154 p += t; n -= t;
4155 q += t; m -= t;
4156 if ((s->sub.left -= t) != 0)
4157 break;
4158 Tracev((stderr, "inflate: stored end, %lu total out\n",
4159 z->total_out + (q >= s->read ? q - s->read :
4160 (s->end - s->read) + (q - s->window))));
4161 s->mode = s->last ? DRY : TYPE;
4162 break;
4163 case TABLE:
4164 NEEDBITS(14)
4165 s->sub.trees.table = t = (uInt)b & 0x3fff;
4166 #ifndef PKZIP_BUG_WORKAROUND
4167 if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29)
4168 {
4169 s->mode = BADB;
4170 z->msg = "too many length or distance symbols";
4171 r = Z_DATA_ERROR;
4172 LEAVE
4173 }
4174 #endif
4175 t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
4176 if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL)
4177 {
4178 r = Z_MEM_ERROR;
4179 LEAVE
4180 }
4181 DUMPBITS(14)
4182 s->sub.trees.index = 0;
4183 Tracev((stderr, "inflate: table sizes ok\n"));
4184 s->mode = BTREE;
4185 case BTREE:
4186 while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10))
4187 {
4188 NEEDBITS(3)
4189 s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7;
4190 DUMPBITS(3)
4191 }
4192 while (s->sub.trees.index < 19)
4193 s->sub.trees.blens[border[s->sub.trees.index++]] = 0;
4194 s->sub.trees.bb = 7;
4195 t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb,
4196 &s->sub.trees.tb, s->hufts, z);
4197 if (t != Z_OK)
4198 {
4199 r = t;
4200 if (r == Z_DATA_ERROR)
4201 {
4202 ZFREE(z, s->sub.trees.blens);
4203 s->mode = BADB;
4204 }
4205 LEAVE
4206 }
4207 s->sub.trees.index = 0;
4208 Tracev((stderr, "inflate: bits tree ok\n"));
4209 s->mode = DTREE;
4210 case DTREE:
4211 while (t = s->sub.trees.table,
4212 s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f))
4213 {
4214 inflate_huft *h;
4215 uInt i, j, c;
4216
4217 t = s->sub.trees.bb;
4218 NEEDBITS(t)
4219 h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]);
4220 t = h->bits;
4221 c = h->base;
4222 if (c < 16)
4223 {
4224 DUMPBITS(t)
4225 s->sub.trees.blens[s->sub.trees.index++] = c;
4226 }
4227 else /* c == 16..18 */
4228 {
4229 i = c == 18 ? 7 : c - 14;
4230 j = c == 18 ? 11 : 3;
4231 NEEDBITS(t + i)
4232 DUMPBITS(t)
4233 j += (uInt)b & inflate_mask[i];
4234 DUMPBITS(i)
4235 i = s->sub.trees.index;
4236 t = s->sub.trees.table;
4237 if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) ||
4238 (c == 16 && i < 1))
4239 {
4240 ZFREE(z, s->sub.trees.blens);
4241 s->mode = BADB;
4242 z->msg = "invalid bit length repeat";
4243 r = Z_DATA_ERROR;
4244 LEAVE
4245 }
4246 c = c == 16 ? s->sub.trees.blens[i - 1] : 0;
4247 do {
4248 s->sub.trees.blens[i++] = c;
4249 } while (--j);
4250 s->sub.trees.index = i;
4251 }
4252 }
4253 s->sub.trees.tb = Z_NULL;
4254 {
4255 uInt bl, bd;
4256 inflate_huft *tl, *td;
4257 inflate_codes_statef *c;
4258
4259 bl = 9; /* must be <= 9 for lookahead assumptions */
4260 bd = 6; /* must be <= 9 for lookahead assumptions */
4261 t = s->sub.trees.table;
4262 t = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f),
4263 s->sub.trees.blens, &bl, &bd, &tl, &td,
4264 s->hufts, z);
4265 if (t != Z_OK)
4266 {
4267 if (t == (uInt)Z_DATA_ERROR)
4268 {
4269 ZFREE(z, s->sub.trees.blens);
4270 s->mode = BADB;
4271 }
4272 r = t;
4273 LEAVE
4274 }
4275 Tracev((stderr, "inflate: trees ok\n"));
4276 if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL)
4277 {
4278 r = Z_MEM_ERROR;
4279 LEAVE
4280 }
4281 s->sub.decode.codes = c;
4282 }
4283 ZFREE(z, s->sub.trees.blens);
4284 s->mode = CODES;
4285 /* FALLTHROUGH */
4286 case CODES:
4287 UPDATE
4288 if ((r = inflate_codes(s, z, r)) != Z_STREAM_END)
4289 return inflate_flush(s, z, r);
4290 r = Z_OK;
4291 inflate_codes_free(s->sub.decode.codes, z);
4292 LOAD
4293 Tracev((stderr, "inflate: codes end, %lu total out\n",
4294 z->total_out + (q >= s->read ? q - s->read :
4295 (s->end - s->read) + (q - s->window))));
4296 if (!s->last)
4297 {
4298 s->mode = TYPE;
4299 break;
4300 }
4301 s->mode = DRY;
4302 /* FALLTHROUGH */
4303 case DRY:
4304 FLUSH
4305 if (s->read != s->write)
4306 LEAVE
4307 s->mode = DONEB;
4308 /* FALLTHROUGH */
4309 case DONEB:
4310 r = Z_STREAM_END;
4311 LEAVE
4312 case BADB:
4313 r = Z_DATA_ERROR;
4314 LEAVE
4315 default:
4316 r = Z_STREAM_ERROR;
4317 LEAVE
4318 }
4319 }
4320
4321
4322 int inflate_blocks_free(inflate_blocks_statef *s, z_streamp z)
4323 {
4324 inflate_blocks_reset(s, z, Z_NULL);
4325 ZFREE(z, s->window);
4326 ZFREE(z, s->hufts);
4327 ZFREE(z, s);
4328 Tracev((stderr, "inflate: blocks freed\n"));
4329 return Z_OK;
4330 }
4331
4332
4333 #if 0
4334 void inflate_set_dictionary(inflate_blocks_statef *s, const Bytef *d, uInt n)
4335 {
4336 zmemcpy(s->window, d, n);
4337 s->read = s->write = s->window + n;
4338 }
4339 #endif
4340
4341 /*
4342 * This subroutine adds the data at next_in/avail_in to the output history
4343 * without performing any output. The output buffer must be "caught up";
4344 * i.e. no pending output (hence s->read equals s->write), and the state must
4345 * be BLOCKS (i.e. we should be willing to see the start of a series of
4346 * BLOCKS). On exit, the output will also be caught up, and the checksum
4347 * will have been updated if need be.
4348 */
4349 int inflate_addhistory(inflate_blocks_statef *s, z_stream *z)
4350 {
4351 uLong b; /* bit buffer */ /* NOT USED HERE */
4352 uInt k; /* bits in bit buffer */ /* NOT USED HERE */
4353 uInt t; /* temporary storage */
4354 Bytef *p; /* input data pointer */
4355 uInt n; /* bytes available there */
4356 Bytef *q; /* output window write pointer */
4357 uInt m; /* bytes to end of window or read pointer */
4358
4359 if (s->read != s->write)
4360 return Z_STREAM_ERROR;
4361 if (s->mode != TYPE)
4362 return Z_DATA_ERROR;
4363
4364 /* we're ready to rock */
4365 LOAD
4366 /* while there is input ready, copy to output buffer, moving
4367 * pointers as needed.
4368 */
4369 while (n) {
4370 t = n; /* how many to do */
4371 /* is there room until end of buffer? */
4372 if (t > m) t = m;
4373 /* update check information */
4374 if (s->checkfn != Z_NULL)
4375 s->check = (*s->checkfn)(s->check, q, t);
4376 zmemcpy(q, p, t);
4377 q += t;
4378 p += t;
4379 n -= t;
4380 z->total_out += t;
4381 s->read = q; /* drag read pointer forward */
4382 /* WWRAP */ /* expand WWRAP macro by hand to handle s->read */
4383 if (q == s->end) {
4384 s->read = q = s->window;
4385 m = WAVAIL;
4386 }
4387 }
4388 UPDATE
4389 return Z_OK;
4390 }
4391
4392
4393 /*
4394 * At the end of a Deflate-compressed PPP packet, we expect to have seen
4395 * a `stored' block type value but not the (zero) length bytes.
4396 */
4397 int inflate_packet_flush(inflate_blocks_statef *s)
4398 {
4399 if (s->mode != LENS)
4400 return Z_DATA_ERROR;
4401 s->mode = TYPE;
4402 return Z_OK;
4403 }
4404
4405 /* Returns true if inflate is currently at the end of a block generated
4406 * by Z_SYNC_FLUSH or Z_FULL_FLUSH.
4407 * IN assertion: s != Z_NULL
4408 */
4409 #if 0
4410 int inflate_blocks_sync_point(s)
4411 inflate_blocks_statef *s;
4412 {
4413 return s->mode == LENS;
4414 }
4415 #endif
4416 /* --- infblock.c */
4417
4418
4419 /* +++ inftrees.c */
4420
4421 /* inftrees.c -- generate Huffman trees for efficient decoding
4422 * Copyright (C) 1995-2002 Mark Adler
4423 * For conditions of distribution and use, see copyright notice in zlib.h
4424 */
4425
4426 /* #include "zutil.h" */
4427 /* #include "inftrees.h" */
4428
4429 #if !defined(BUILDFIXED) && !defined(STDC)
4430 # define BUILDFIXED /* non ANSI compilers may not accept inffixed.h */
4431 #endif
4432
4433 const char inflate_copyright[] =
4434 " inflate 1.1.4 Copyright 1995-2002 Mark Adler ";
4435 /*
4436 If you use the zlib library in a product, an acknowledgment is welcome
4437 in the documentation of your product. If for some reason you cannot
4438 include such an acknowledgment, I would appreciate that you keep this
4439 copyright string in the executable of your product.
4440 */
4441
4442 #ifndef NO_DUMMY_DECL
4443 struct internal_state {int dummy;}; /* for buggy compilers */
4444 #endif
4445
4446 /* simplify the use of the inflate_huft type with some defines */
4447 #define exop word.what.Exop
4448 #define bits word.what.Bits
4449
4450
4451 local int huft_build(
4452 uIntf *, /* code lengths in bits */
4453 uInt, /* number of codes */
4454 uInt, /* number of "simple" codes */
4455 const uIntf *, /* list of base values for non-simple codes */
4456 const uIntf *, /* list of extra bits for non-simple codes */
4457 inflate_huft * FAR*,/* result: starting table */
4458 uIntf *, /* maximum lookup bits (returns actual) */
4459 inflate_huft *, /* space for trees */
4460 uInt *, /* hufts used in space */
4461 uIntf * ); /* space for values */
4462
4463 /* Tables for deflate from PKZIP's appnote.txt. */
4464 local const uInt cplens[31] = { /* Copy lengths for literal codes 257..285 */
4465 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
4466 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
4467 /* see note #13 above about 258 */
4468 local const uInt cplext[31] = { /* Extra bits for literal codes 257..285 */
4469 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
4470 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 112, 112}; /* 112==invalid */
4471 local const uInt cpdist[30] = { /* Copy offsets for distance codes 0..29 */
4472 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
4473 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
4474 8193, 12289, 16385, 24577};
4475 local const uInt cpdext[30] = { /* Extra bits for distance codes */
4476 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
4477 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
4478 12, 12, 13, 13};
4479
4480 /*
4481 Huffman code decoding is performed using a multi-level table lookup.
4482 The fastest way to decode is to simply build a lookup table whose
4483 size is determined by the longest code. However, the time it takes
4484 to build this table can also be a factor if the data being decoded
4485 is not very long. The most common codes are necessarily the
4486 shortest codes, so those codes dominate the decoding time, and hence
4487 the speed. The idea is you can have a shorter table that decodes the
4488 shorter, more probable codes, and then point to subsidiary tables for
4489 the longer codes. The time it costs to decode the longer codes is
4490 then traded against the time it takes to make longer tables.
4491
4492 This results of this trade are in the variables lbits and dbits
4493 below. lbits is the number of bits the first level table for literal/
4494 length codes can decode in one step, and dbits is the same thing for
4495 the distance codes. Subsequent tables are also less than or equal to
4496 those sizes. These values may be adjusted either when all of the
4497 codes are shorter than that, in which case the longest code length in
4498 bits is used, or when the shortest code is *longer* than the requested
4499 table size, in which case the length of the shortest code in bits is
4500 used.
4501
4502 There are two different values for the two tables, since they code a
4503 different number of possibilities each. The literal/length table
4504 codes 286 possible values, or in a flat code, a little over eight
4505 bits. The distance table codes 30 possible values, or a little less
4506 than five bits, flat. The optimum values for speed end up being
4507 about one bit more than those, so lbits is 8+1 and dbits is 5+1.
4508 The optimum values may differ though from machine to machine, and
4509 possibly even between compilers. Your mileage may vary.
4510 */
4511
4512
4513 /* If BMAX needs to be larger than 16, then h and x[] should be uLong. */
4514 #define BMAX 15 /* maximum bit length of any code */
4515
4516 local int huft_build(uIntf *b, /* code lengths in bits (all assumed <= BMAX) */
4517 uInt n, /* number of codes (assumed <= 288) */
4518 uInt s, /* number of simple-valued codes (0..s-1) */
4519 const uIntf *d, /* list of base values for non-simple codes */
4520 const uIntf *e, /* list of extra bits for non-simple codes */
4521 inflate_huft * FAR *t, /* result: starting table */
4522 uIntf *m, /* maximum lookup bits, returns actual */
4523 inflate_huft *hp, /* space for trees */
4524 uInt *hn, /* hufts used in space */
4525 uIntf *v) /* working area: values in order of bit length */
4526
4527 /* Given a list of code lengths and a maximum table size, make a set of
4528 tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR
4529 if the given code set is incomplete (the tables are still built in this
4530 case), or Z_DATA_ERROR if the input is invalid. */
4531 {
4532
4533 uInt a; /* counter for codes of length k */
4534 uInt c[BMAX+1]; /* bit length count table */
4535 uInt f; /* i repeats in table every f entries */
4536 int g; /* maximum code length */
4537 int h; /* table level */
4538 uInt i; /* counter, current code */
4539 uInt j; /* counter */
4540 int k; /* number of bits in current code */
4541 int l; /* bits per table (returned in m) */
4542 uInt mask; /* (1 << w) - 1, to avoid cc -O bug on HP */
4543 uIntf *p; /* pointer into c[], b[], or v[] */
4544 inflate_huft *q; /* points to current table */
4545 struct inflate_huft_s r; /* table entry for structure assignment */
4546 inflate_huft *u[BMAX]; /* table stack */
4547 int w; /* bits before this table == (l * h) */
4548 uInt x[BMAX+1]; /* bit offsets, then code stack */
4549 uIntf *xp; /* pointer into x */
4550 int y; /* number of dummy codes added */
4551 uInt z; /* number of entries in current table */
4552
4553 r.base = 0; /* XXX gcc */
4554
4555 /* Generate counts for each bit length */
4556 p = c;
4557 #define C0 *p++ = 0;
4558 #define C2 C0 C0 C0 C0
4559 #define C4 C2 C2 C2 C2
4560 C4 /* clear c[]--assume BMAX+1 is 16 */
4561 p = b; i = n;
4562 do {
4563 c[*p++]++; /* assume all entries <= BMAX */
4564 } while (--i);
4565 if (c[0] == n) /* null input--all zero length codes */
4566 {
4567 *t = (inflate_huft *)Z_NULL;
4568 *m = 0;
4569 return Z_OK;
4570 }
4571
4572
4573 /* Find minimum and maximum length, bound *m by those */
4574 l = *m;
4575 for (j = 1; j <= BMAX; j++)
4576 if (c[j])
4577 break;
4578 k = j; /* minimum code length */
4579 if ((uInt)l < j)
4580 l = j;
4581 for (i = BMAX; i; i--)
4582 if (c[i])
4583 break;
4584 g = i; /* maximum code length */
4585 if ((uInt)l > i)
4586 l = i;
4587 *m = l;
4588
4589
4590 /* Adjust last length count to fill out codes, if needed */
4591 for (y = 1 << j; j < i; j++, y <<= 1)
4592 if ((y -= c[j]) < 0)
4593 return Z_DATA_ERROR;
4594 if ((y -= c[i]) < 0)
4595 return Z_DATA_ERROR;
4596 c[i] += y;
4597
4598
4599 /* Generate starting offsets into the value table for each length */
4600 x[1] = j = 0;
4601 p = c + 1; xp = x + 2;
4602 while (--i) { /* note that i == g from above */
4603 *xp++ = (j += *p++);
4604 }
4605
4606
4607 /* Make a table of values in order of bit lengths */
4608 p = b; i = 0;
4609 do {
4610 if ((j = *p++) != 0)
4611 v[x[j]++] = i;
4612 } while (++i < n);
4613 n = x[g]; /* set n to length of v */
4614
4615
4616 /* Generate the Huffman codes and for each, make the table entries */
4617 x[0] = i = 0; /* first Huffman code is zero */
4618 p = v; /* grab values in bit order */
4619 h = -1; /* no tables yet--level -1 */
4620 w = -l; /* bits decoded == (l * h) */
4621 u[0] = (inflate_huft *)Z_NULL; /* just to keep compilers happy */
4622 q = (inflate_huft *)Z_NULL; /* ditto */
4623 z = 0; /* ditto */
4624
4625 /* go through the bit lengths (k already is bits in shortest code) */
4626 for (; k <= g; k++)
4627 {
4628 a = c[k];
4629 while (a--)
4630 {
4631 /* here i is the Huffman code of length k bits for value *p */
4632 /* make tables up to required level */
4633 while (k > w + l)
4634 {
4635 h++;
4636 w += l; /* previous table always l bits */
4637
4638 /* compute minimum size table less than or equal to l bits */
4639 z = g - w;
4640 z = z > (uInt)l ? l : z; /* table size upper limit */
4641 if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */
4642 { /* too few codes for k-w bit table */
4643 f -= a + 1; /* deduct codes from patterns left */
4644 xp = c + k;
4645 if (j < z)
4646 while (++j < z) /* try smaller tables up to z bits */
4647 {
4648 if ((f <<= 1) <= *++xp)
4649 break; /* enough codes to use up j bits */
4650 f -= *xp; /* else deduct codes from patterns */
4651 }
4652 }
4653 z = 1 << j; /* table entries for j-bit table */
4654
4655 /* allocate new table */
4656 if (*hn + z > MANY) /* (note: doesn't matter for fixed) */
4657 return Z_DATA_ERROR; /* overflow of MANY */
4658 u[h] = q = hp + *hn;
4659 *hn += z;
4660
4661 /* connect to last table, if there is one */
4662 if (h)
4663 {
4664 x[h] = i; /* save pattern for backing up */
4665 r.bits = (Byte)l; /* bits to dump before this table */
4666 r.exop = (Byte)j; /* bits in this table */
4667 j = i >> (w - l);
4668 r.base = (uInt)(q - u[h-1] - j); /* offset to this table */
4669 u[h-1][j] = r; /* connect to last table */
4670 }
4671 else
4672 *t = q; /* first table is returned result */
4673 }
4674
4675 /* set up table entry in r */
4676 r.bits = (Byte)(k - w);
4677 if (p >= v + n)
4678 r.exop = 128 + 64; /* out of values--invalid code */
4679 else if (*p < s)
4680 {
4681 r.exop = (Byte)(*p < 256 ? 0 : 32 + 64); /* 256 is end-of-block */
4682 r.base = *p++; /* simple code is just the value */
4683 }
4684 else
4685 {
4686 r.exop = (Byte)(e[*p - s] + 16 + 64);/* non-simple--look up in lists */
4687 r.base = d[*p++ - s];
4688 }
4689
4690 /* fill code-like entries with r */
4691 f = 1 << (k - w);
4692 for (j = i >> w; j < z; j += f)
4693 q[j] = r;
4694
4695 /* backwards increment the k-bit code i */
4696 for (j = 1 << (k - 1); i & j; j >>= 1)
4697 i ^= j;
4698 i ^= j;
4699
4700 /* backup over finished tables */
4701 mask = (1 << w) - 1; /* needed on HP, cc -O bug */
4702 if (h == -1)
4703 return Z_BUF_ERROR;
4704 while ((i & mask) != x[h])
4705 {
4706 h--; /* don't need to update q */
4707 w -= l;
4708 mask = (1 << w) - 1;
4709 }
4710 }
4711 }
4712
4713
4714 /* Return Z_BUF_ERROR if we were given an incomplete table */
4715 return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK;
4716 }
4717
4718
4719 int inflate_trees_bits(uIntf *c, /* 19 code lengths */
4720 uIntf *bb, /* bits tree desired/actual depth */
4721 inflate_huft * FAR *tb, /* bits tree result */
4722 inflate_huft *hp, /* space for trees */
4723 z_streamp z) /* for message */
4724 {
4725 int r;
4726 uInt hn = 0; /* hufts used in space */
4727 uIntf *v; /* work area for huft_build */
4728
4729 if ((v = (uIntf*)ZALLOC(z, 19, sizeof(uInt))) == Z_NULL)
4730 return Z_MEM_ERROR;
4731 r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL,
4732 tb, bb, hp, &hn, v);
4733 if (r == Z_DATA_ERROR)
4734 z->msg = "oversubscribed dynamic bit lengths tree";
4735 else if (r == Z_BUF_ERROR || *bb == 0)
4736 {
4737 z->msg = "incomplete dynamic bit lengths tree";
4738 r = Z_DATA_ERROR;
4739 }
4740 ZFREE(z, v);
4741 return r;
4742 }
4743
4744
4745 int inflate_trees_dynamic(uInt nl,
4746 uInt nd, /* number of literal/length codes */
4747 uIntf *c, /* number of distance codes */
4748 uIntf *bl, /* that many (total) code lengths */
4749 uIntf *bd, /* literal desired/actual bit depth */
4750 inflate_huft * FAR *tl, /* literal/length tree result */
4751 inflate_huft * FAR *td, /* distance tree result */
4752 inflate_huft *hp, /* space for trees */
4753 z_streamp z) /* for message */
4754 {
4755 int r;
4756 uInt hn = 0; /* hufts used in space */
4757 uIntf *v; /* work area for huft_build */
4758
4759 /* allocate work area */
4760 if ((v = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
4761 return Z_MEM_ERROR;
4762
4763 /* build literal/length tree */
4764 r = huft_build(c, nl, 257, cplens, cplext, tl, bl, hp, &hn, v);
4765 if (r != Z_OK || *bl == 0)
4766 {
4767 if (r == Z_DATA_ERROR)
4768 z->msg = "oversubscribed literal/length tree";
4769 else if (r != Z_MEM_ERROR)
4770 {
4771 z->msg = "incomplete literal/length tree";
4772 r = Z_DATA_ERROR;
4773 }
4774 ZFREE(z, v);
4775 return r;
4776 }
4777
4778 /* build distance tree */
4779 r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, hp, &hn, v);
4780 if (r != Z_OK || (*bd == 0 && nl > 257))
4781 {
4782 if (r == Z_DATA_ERROR)
4783 z->msg = "oversubscribed distance tree";
4784 else if (r == Z_BUF_ERROR) {
4785 #ifdef PKZIP_BUG_WORKAROUND
4786 r = Z_OK;
4787 }
4788 #else
4789 z->msg = "incomplete distance tree";
4790 r = Z_DATA_ERROR;
4791 }
4792 else if (r != Z_MEM_ERROR)
4793 {
4794 z->msg = "empty distance tree with lengths";
4795 r = Z_DATA_ERROR;
4796 }
4797 ZFREE(z, v);
4798 return r;
4799 #endif
4800 }
4801
4802 /* done */
4803 ZFREE(z, v);
4804 return Z_OK;
4805 }
4806
4807
4808 /* build fixed tables only once--keep them here */
4809 #ifdef BUILDFIXED
4810 local int fixed_built = 0;
4811 #define FIXEDH 544 /* number of hufts used by fixed tables */
4812 local inflate_huft fixed_mem[FIXEDH];
4813 local uInt fixed_bl;
4814 local uInt fixed_bd;
4815 local inflate_huft *fixed_tl;
4816 local inflate_huft *fixed_td;
4817 #else
4818
4819 /* +++ inffixed.h */
4820 /* inffixed.h -- table for decoding fixed codes
4821 * Generated automatically by the maketree.c program
4822 */
4823
4824 /* WARNING: this file should *not* be used by applications. It is
4825 part of the implementation of the compression library and is
4826 subject to change. Applications should only use zlib.h.
4827 */
4828
4829 local uInt fixed_bl = 9;
4830 local uInt fixed_bd = 5;
4831 local inflate_huft fixed_tl[] = {
4832 {{{96,7}},256}, {{{0,8}},80}, {{{0,8}},16}, {{{84,8}},115},
4833 {{{82,7}},31}, {{{0,8}},112}, {{{0,8}},48}, {{{0,9}},192},
4834 {{{80,7}},10}, {{{0,8}},96}, {{{0,8}},32}, {{{0,9}},160},
4835 {{{0,8}},0}, {{{0,8}},128}, {{{0,8}},64}, {{{0,9}},224},
4836 {{{80,7}},6}, {{{0,8}},88}, {{{0,8}},24}, {{{0,9}},144},
4837 {{{83,7}},59}, {{{0,8}},120}, {{{0,8}},56}, {{{0,9}},208},
4838 {{{81,7}},17}, {{{0,8}},104}, {{{0,8}},40}, {{{0,9}},176},
4839 {{{0,8}},8}, {{{0,8}},136}, {{{0,8}},72}, {{{0,9}},240},
4840 {{{80,7}},4}, {{{0,8}},84}, {{{0,8}},20}, {{{85,8}},227},
4841 {{{83,7}},43}, {{{0,8}},116}, {{{0,8}},52}, {{{0,9}},200},
4842 {{{81,7}},13}, {{{0,8}},100}, {{{0,8}},36}, {{{0,9}},168},
4843 {{{0,8}},4}, {{{0,8}},132}, {{{0,8}},68}, {{{0,9}},232},
4844 {{{80,7}},8}, {{{0,8}},92}, {{{0,8}},28}, {{{0,9}},152},
4845 {{{84,7}},83}, {{{0,8}},124}, {{{0,8}},60}, {{{0,9}},216},
4846 {{{82,7}},23}, {{{0,8}},108}, {{{0,8}},44}, {{{0,9}},184},
4847 {{{0,8}},12}, {{{0,8}},140}, {{{0,8}},76}, {{{0,9}},248},
4848 {{{80,7}},3}, {{{0,8}},82}, {{{0,8}},18}, {{{85,8}},163},
4849 {{{83,7}},35}, {{{0,8}},114}, {{{0,8}},50}, {{{0,9}},196},
4850 {{{81,7}},11}, {{{0,8}},98}, {{{0,8}},34}, {{{0,9}},164},
4851 {{{0,8}},2}, {{{0,8}},130}, {{{0,8}},66}, {{{0,9}},228},
4852 {{{80,7}},7}, {{{0,8}},90}, {{{0,8}},26}, {{{0,9}},148},
4853 {{{84,7}},67}, {{{0,8}},122}, {{{0,8}},58}, {{{0,9}},212},
4854 {{{82,7}},19}, {{{0,8}},106}, {{{0,8}},42}, {{{0,9}},180},
4855 {{{0,8}},10}, {{{0,8}},138}, {{{0,8}},74}, {{{0,9}},244},
4856 {{{80,7}},5}, {{{0,8}},86}, {{{0,8}},22}, {{{192,8}},0},
4857 {{{83,7}},51}, {{{0,8}},118}, {{{0,8}},54}, {{{0,9}},204},
4858 {{{81,7}},15}, {{{0,8}},102}, {{{0,8}},38}, {{{0,9}},172},
4859 {{{0,8}},6}, {{{0,8}},134}, {{{0,8}},70}, {{{0,9}},236},
4860 {{{80,7}},9}, {{{0,8}},94}, {{{0,8}},30}, {{{0,9}},156},
4861 {{{84,7}},99}, {{{0,8}},126}, {{{0,8}},62}, {{{0,9}},220},
4862 {{{82,7}},27}, {{{0,8}},110}, {{{0,8}},46}, {{{0,9}},188},
4863 {{{0,8}},14}, {{{0,8}},142}, {{{0,8}},78}, {{{0,9}},252},
4864 {{{96,7}},256}, {{{0,8}},81}, {{{0,8}},17}, {{{85,8}},131},
4865 {{{82,7}},31}, {{{0,8}},113}, {{{0,8}},49}, {{{0,9}},194},
4866 {{{80,7}},10}, {{{0,8}},97}, {{{0,8}},33}, {{{0,9}},162},
4867 {{{0,8}},1}, {{{0,8}},129}, {{{0,8}},65}, {{{0,9}},226},
4868 {{{80,7}},6}, {{{0,8}},89}, {{{0,8}},25}, {{{0,9}},146},
4869 {{{83,7}},59}, {{{0,8}},121}, {{{0,8}},57}, {{{0,9}},210},
4870 {{{81,7}},17}, {{{0,8}},105}, {{{0,8}},41}, {{{0,9}},178},
4871 {{{0,8}},9}, {{{0,8}},137}, {{{0,8}},73}, {{{0,9}},242},
4872 {{{80,7}},4}, {{{0,8}},85}, {{{0,8}},21}, {{{80,8}},258},
4873 {{{83,7}},43}, {{{0,8}},117}, {{{0,8}},53}, {{{0,9}},202},
4874 {{{81,7}},13}, {{{0,8}},101}, {{{0,8}},37}, {{{0,9}},170},
4875 {{{0,8}},5}, {{{0,8}},133}, {{{0,8}},69}, {{{0,9}},234},
4876 {{{80,7}},8}, {{{0,8}},93}, {{{0,8}},29}, {{{0,9}},154},
4877 {{{84,7}},83}, {{{0,8}},125}, {{{0,8}},61}, {{{0,9}},218},
4878 {{{82,7}},23}, {{{0,8}},109}, {{{0,8}},45}, {{{0,9}},186},
4879 {{{0,8}},13}, {{{0,8}},141}, {{{0,8}},77}, {{{0,9}},250},
4880 {{{80,7}},3}, {{{0,8}},83}, {{{0,8}},19}, {{{85,8}},195},
4881 {{{83,7}},35}, {{{0,8}},115}, {{{0,8}},51}, {{{0,9}},198},
4882 {{{81,7}},11}, {{{0,8}},99}, {{{0,8}},35}, {{{0,9}},166},
4883 {{{0,8}},3}, {{{0,8}},131}, {{{0,8}},67}, {{{0,9}},230},
4884 {{{80,7}},7}, {{{0,8}},91}, {{{0,8}},27}, {{{0,9}},150},
4885 {{{84,7}},67}, {{{0,8}},123}, {{{0,8}},59}, {{{0,9}},214},
4886 {{{82,7}},19}, {{{0,8}},107}, {{{0,8}},43}, {{{0,9}},182},
4887 {{{0,8}},11}, {{{0,8}},139}, {{{0,8}},75}, {{{0,9}},246},
4888 {{{80,7}},5}, {{{0,8}},87}, {{{0,8}},23}, {{{192,8}},0},
4889 {{{83,7}},51}, {{{0,8}},119}, {{{0,8}},55}, {{{0,9}},206},
4890 {{{81,7}},15}, {{{0,8}},103}, {{{0,8}},39}, {{{0,9}},174},
4891 {{{0,8}},7}, {{{0,8}},135}, {{{0,8}},71}, {{{0,9}},238},
4892 {{{80,7}},9}, {{{0,8}},95}, {{{0,8}},31}, {{{0,9}},158},
4893 {{{84,7}},99}, {{{0,8}},127}, {{{0,8}},63}, {{{0,9}},222},
4894 {{{82,7}},27}, {{{0,8}},111}, {{{0,8}},47}, {{{0,9}},190},
4895 {{{0,8}},15}, {{{0,8}},143}, {{{0,8}},79}, {{{0,9}},254},
4896 {{{96,7}},256}, {{{0,8}},80}, {{{0,8}},16}, {{{84,8}},115},
4897 {{{82,7}},31}, {{{0,8}},112}, {{{0,8}},48}, {{{0,9}},193},
4898 {{{80,7}},10}, {{{0,8}},96}, {{{0,8}},32}, {{{0,9}},161},
4899 {{{0,8}},0}, {{{0,8}},128}, {{{0,8}},64}, {{{0,9}},225},
4900 {{{80,7}},6}, {{{0,8}},88}, {{{0,8}},24}, {{{0,9}},145},
4901 {{{83,7}},59}, {{{0,8}},120}, {{{0,8}},56}, {{{0,9}},209},
4902 {{{81,7}},17}, {{{0,8}},104}, {{{0,8}},40}, {{{0,9}},177},
4903 {{{0,8}},8}, {{{0,8}},136}, {{{0,8}},72}, {{{0,9}},241},
4904 {{{80,7}},4}, {{{0,8}},84}, {{{0,8}},20}, {{{85,8}},227},
4905 {{{83,7}},43}, {{{0,8}},116}, {{{0,8}},52}, {{{0,9}},201},
4906 {{{81,7}},13}, {{{0,8}},100}, {{{0,8}},36}, {{{0,9}},169},
4907 {{{0,8}},4}, {{{0,8}},132}, {{{0,8}},68}, {{{0,9}},233},
4908 {{{80,7}},8}, {{{0,8}},92}, {{{0,8}},28}, {{{0,9}},153},
4909 {{{84,7}},83}, {{{0,8}},124}, {{{0,8}},60}, {{{0,9}},217},
4910 {{{82,7}},23}, {{{0,8}},108}, {{{0,8}},44}, {{{0,9}},185},
4911 {{{0,8}},12}, {{{0,8}},140}, {{{0,8}},76}, {{{0,9}},249},
4912 {{{80,7}},3}, {{{0,8}},82}, {{{0,8}},18}, {{{85,8}},163},
4913 {{{83,7}},35}, {{{0,8}},114}, {{{0,8}},50}, {{{0,9}},197},
4914 {{{81,7}},11}, {{{0,8}},98}, {{{0,8}},34}, {{{0,9}},165},
4915 {{{0,8}},2}, {{{0,8}},130}, {{{0,8}},66}, {{{0,9}},229},
4916 {{{80,7}},7}, {{{0,8}},90}, {{{0,8}},26}, {{{0,9}},149},
4917 {{{84,7}},67}, {{{0,8}},122}, {{{0,8}},58}, {{{0,9}},213},
4918 {{{82,7}},19}, {{{0,8}},106}, {{{0,8}},42}, {{{0,9}},181},
4919 {{{0,8}},10}, {{{0,8}},138}, {{{0,8}},74}, {{{0,9}},245},
4920 {{{80,7}},5}, {{{0,8}},86}, {{{0,8}},22}, {{{192,8}},0},
4921 {{{83,7}},51}, {{{0,8}},118}, {{{0,8}},54}, {{{0,9}},205},
4922 {{{81,7}},15}, {{{0,8}},102}, {{{0,8}},38}, {{{0,9}},173},
4923 {{{0,8}},6}, {{{0,8}},134}, {{{0,8}},70}, {{{0,9}},237},
4924 {{{80,7}},9}, {{{0,8}},94}, {{{0,8}},30}, {{{0,9}},157},
4925 {{{84,7}},99}, {{{0,8}},126}, {{{0,8}},62}, {{{0,9}},221},
4926 {{{82,7}},27}, {{{0,8}},110}, {{{0,8}},46}, {{{0,9}},189},
4927 {{{0,8}},14}, {{{0,8}},142}, {{{0,8}},78}, {{{0,9}},253},
4928 {{{96,7}},256}, {{{0,8}},81}, {{{0,8}},17}, {{{85,8}},131},
4929 {{{82,7}},31}, {{{0,8}},113}, {{{0,8}},49}, {{{0,9}},195},
4930 {{{80,7}},10}, {{{0,8}},97}, {{{0,8}},33}, {{{0,9}},163},
4931 {{{0,8}},1}, {{{0,8}},129}, {{{0,8}},65}, {{{0,9}},227},
4932 {{{80,7}},6}, {{{0,8}},89}, {{{0,8}},25}, {{{0,9}},147},
4933 {{{83,7}},59}, {{{0,8}},121}, {{{0,8}},57}, {{{0,9}},211},
4934 {{{81,7}},17}, {{{0,8}},105}, {{{0,8}},41}, {{{0,9}},179},
4935 {{{0,8}},9}, {{{0,8}},137}, {{{0,8}},73}, {{{0,9}},243},
4936 {{{80,7}},4}, {{{0,8}},85}, {{{0,8}},21}, {{{80,8}},258},
4937 {{{83,7}},43}, {{{0,8}},117}, {{{0,8}},53}, {{{0,9}},203},
4938 {{{81,7}},13}, {{{0,8}},101}, {{{0,8}},37}, {{{0,9}},171},
4939 {{{0,8}},5}, {{{0,8}},133}, {{{0,8}},69}, {{{0,9}},235},
4940 {{{80,7}},8}, {{{0,8}},93}, {{{0,8}},29}, {{{0,9}},155},
4941 {{{84,7}},83}, {{{0,8}},125}, {{{0,8}},61}, {{{0,9}},219},
4942 {{{82,7}},23}, {{{0,8}},109}, {{{0,8}},45}, {{{0,9}},187},
4943 {{{0,8}},13}, {{{0,8}},141}, {{{0,8}},77}, {{{0,9}},251},
4944 {{{80,7}},3}, {{{0,8}},83}, {{{0,8}},19}, {{{85,8}},195},
4945 {{{83,7}},35}, {{{0,8}},115}, {{{0,8}},51}, {{{0,9}},199},
4946 {{{81,7}},11}, {{{0,8}},99}, {{{0,8}},35}, {{{0,9}},167},
4947 {{{0,8}},3}, {{{0,8}},131}, {{{0,8}},67}, {{{0,9}},231},
4948 {{{80,7}},7}, {{{0,8}},91}, {{{0,8}},27}, {{{0,9}},151},
4949 {{{84,7}},67}, {{{0,8}},123}, {{{0,8}},59}, {{{0,9}},215},
4950 {{{82,7}},19}, {{{0,8}},107}, {{{0,8}},43}, {{{0,9}},183},
4951 {{{0,8}},11}, {{{0,8}},139}, {{{0,8}},75}, {{{0,9}},247},
4952 {{{80,7}},5}, {{{0,8}},87}, {{{0,8}},23}, {{{192,8}},0},
4953 {{{83,7}},51}, {{{0,8}},119}, {{{0,8}},55}, {{{0,9}},207},
4954 {{{81,7}},15}, {{{0,8}},103}, {{{0,8}},39}, {{{0,9}},175},
4955 {{{0,8}},7}, {{{0,8}},135}, {{{0,8}},71}, {{{0,9}},239},
4956 {{{80,7}},9}, {{{0,8}},95}, {{{0,8}},31}, {{{0,9}},159},
4957 {{{84,7}},99}, {{{0,8}},127}, {{{0,8}},63}, {{{0,9}},223},
4958 {{{82,7}},27}, {{{0,8}},111}, {{{0,8}},47}, {{{0,9}},191},
4959 {{{0,8}},15}, {{{0,8}},143}, {{{0,8}},79}, {{{0,9}},255}
4960 };
4961 local inflate_huft fixed_td[] = {
4962 {{{80,5}},1}, {{{87,5}},257}, {{{83,5}},17}, {{{91,5}},4097},
4963 {{{81,5}},5}, {{{89,5}},1025}, {{{85,5}},65}, {{{93,5}},16385},
4964 {{{80,5}},3}, {{{88,5}},513}, {{{84,5}},33}, {{{92,5}},8193},
4965 {{{82,5}},9}, {{{90,5}},2049}, {{{86,5}},129}, {{{192,5}},24577},
4966 {{{80,5}},2}, {{{87,5}},385}, {{{83,5}},25}, {{{91,5}},6145},
4967 {{{81,5}},7}, {{{89,5}},1537}, {{{85,5}},97}, {{{93,5}},24577},
4968 {{{80,5}},4}, {{{88,5}},769}, {{{84,5}},49}, {{{92,5}},12289},
4969 {{{82,5}},13}, {{{90,5}},3073}, {{{86,5}},193}, {{{192,5}},24577}
4970 };
4971 /* --- inffixed.h */
4972
4973 #endif
4974
4975
inflate_trees_fixed(uIntf * bl,uIntf * bd,inflate_huft * FAR * tl,inflate_huft * FAR * td,z_streamp z)4976 int inflate_trees_fixed(
4977 uIntf *bl, /* literal desired/actual bit depth */
4978 uIntf *bd, /* distance desired/actual bit depth */
4979 inflate_huft * FAR *tl, /* literal/length tree result */
4980 inflate_huft * FAR *td, /* distance tree result */
4981 z_streamp z) /* for memory allocation */
4982 {
4983 #ifdef BUILDFIXED
4984 /* build fixed tables if not already */
4985 if (!fixed_built)
4986 {
4987 int k; /* temporary variable */
4988 uInt f = 0; /* number of hufts used in fixed_mem */
4989 uIntf *c; /* length list for huft_build */
4990 uIntf *v; /* work area for huft_build */
4991
4992 /* allocate memory */
4993 if ((c = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
4994 return Z_MEM_ERROR;
4995 if ((v = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
4996 {
4997 ZFREE(z, c);
4998 return Z_MEM_ERROR;
4999 }
5000
5001 /* literal table */
5002 for (k = 0; k < 144; k++)
5003 c[k] = 8;
5004 for (; k < 256; k++)
5005 c[k] = 9;
5006 for (; k < 280; k++)
5007 c[k] = 7;
5008 for (; k < 288; k++)
5009 c[k] = 8;
5010 fixed_bl = 9;
5011 huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl,
5012 fixed_mem, &f, v);
5013
5014 /* distance table */
5015 for (k = 0; k < 30; k++)
5016 c[k] = 5;
5017 fixed_bd = 5;
5018 huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd,
5019 fixed_mem, &f, v);
5020
5021 /* done */
5022 ZFREE(z, v);
5023 ZFREE(z, c);
5024 fixed_built = 1;
5025 }
5026 #endif
5027 *bl = fixed_bl;
5028 *bd = fixed_bd;
5029 *tl = fixed_tl;
5030 *td = fixed_td;
5031 return Z_OK;
5032 }
5033 /* --- inftrees.c */
5034
5035 /* +++ infcodes.c */
5036
5037 /* infcodes.c -- process literals and length/distance pairs
5038 * Copyright (C) 1995-2002 Mark Adler
5039 * For conditions of distribution and use, see copyright notice in zlib.h
5040 */
5041
5042 /* #include "zutil.h" */
5043 /* #include "inftrees.h" */
5044 /* #include "infblock.h" */
5045 /* #include "infcodes.h" */
5046 /* #include "infutil.h" */
5047
5048 /* +++ inffast.h */
5049
5050 /* inffast.h -- header to use inffast.c
5051 * Copyright (C) 1995-2002 Mark Adler
5052 * For conditions of distribution and use, see copyright notice in zlib.h
5053 */
5054
5055 /* WARNING: this file should *not* be used by applications. It is
5056 part of the implementation of the compression library and is
5057 subject to change. Applications should only use zlib.h.
5058 */
5059
5060 extern int inflate_fast(
5061 uInt,
5062 uInt,
5063 inflate_huft *,
5064 inflate_huft *,
5065 inflate_blocks_statef *,
5066 z_streamp );
5067 /* --- inffast.h */
5068
5069 /* simplify the use of the inflate_huft type with some defines */
5070 #define exop word.what.Exop
5071 #define bits word.what.Bits
5072
5073 typedef enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
5074 START, /* x: set up for LEN */
5075 LEN, /* i: get length/literal/eob next */
5076 LENEXT, /* i: getting length extra (have base) */
5077 DIST, /* i: get distance next */
5078 DISTEXT, /* i: getting distance extra */
5079 COPY, /* o: copying bytes in window, waiting for space */
5080 LIT, /* o: got literal, waiting for output space */
5081 WASH, /* o: got eob, possibly still output waiting */
5082 END, /* x: got eob and all data flushed */
5083 BADCODE} /* x: got error */
5084 inflate_codes_mode;
5085
5086 /* inflate codes private state */
5087 struct inflate_codes_state {
5088
5089 /* mode */
5090 inflate_codes_mode mode; /* current inflate_codes mode */
5091
5092 /* mode dependent information */
5093 uInt len;
5094 union {
5095 struct {
5096 inflate_huft *tree; /* pointer into tree */
5097 uInt need; /* bits needed */
5098 } code; /* if LEN or DIST, where in tree */
5099 uInt lit; /* if LIT, literal */
5100 struct {
5101 uInt get; /* bits to get for extra */
5102 uInt dist; /* distance back to copy from */
5103 } copy; /* if EXT or COPY, where and how much */
5104 } sub; /* submode */
5105
5106 /* mode independent information */
5107 Byte lbits; /* ltree bits decoded per branch */
5108 Byte dbits; /* dtree bits decoder per branch */
5109 inflate_huft *ltree; /* literal/length/eob tree */
5110 inflate_huft *dtree; /* distance tree */
5111
5112 };
5113
5114
inflate_codes_new(uInt bl,uInt bd,inflate_huft * tl,inflate_huft * td,z_streamp z)5115 inflate_codes_statef *inflate_codes_new(uInt bl, uInt bd,
5116 inflate_huft *tl, inflate_huft *td, z_streamp z)
5117 {
5118 inflate_codes_statef *c;
5119
5120 if ((c = (inflate_codes_statef *)
5121 ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL)
5122 {
5123 c->mode = START;
5124 c->lbits = (Byte)bl;
5125 c->dbits = (Byte)bd;
5126 c->ltree = tl;
5127 c->dtree = td;
5128 Tracev((stderr, "inflate: codes new\n"));
5129 }
5130 return c;
5131 }
5132
5133
inflate_codes(inflate_blocks_statef * s,z_streamp z,int r)5134 int inflate_codes(inflate_blocks_statef *s, z_streamp z, int r)
5135 {
5136 uInt j; /* temporary storage */
5137 inflate_huft *t; /* temporary pointer */
5138 uInt e; /* extra bits or operation */
5139 uLong b; /* bit buffer */
5140 uInt k; /* bits in bit buffer */
5141 Bytef *p; /* input data pointer */
5142 uInt n; /* bytes available there */
5143 Bytef *q; /* output window write pointer */
5144 uInt m; /* bytes to end of window or read pointer */
5145 Bytef *f; /* pointer to copy strings from */
5146 inflate_codes_statef *c = s->sub.decode.codes; /* codes state */
5147
5148 /* copy input/output information to locals (UPDATE macro restores) */
5149 LOAD
5150
5151 /* process input and output based on current state */
5152 while (1) switch (c->mode)
5153 { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
5154 case START: /* x: set up for LEN */
5155 #ifndef SLOW
5156 if (m >= 258 && n >= 10)
5157 {
5158 UPDATE
5159 r = inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z);
5160 LOAD
5161 if (r != Z_OK)
5162 {
5163 c->mode = r == Z_STREAM_END ? WASH : BADCODE;
5164 break;
5165 }
5166 }
5167 #endif /* !SLOW */
5168 c->sub.code.need = c->lbits;
5169 c->sub.code.tree = c->ltree;
5170 c->mode = LEN;
5171 /* FALLTHROUGH */
5172 case LEN: /* i: get length/literal/eob next */
5173 j = c->sub.code.need;
5174 NEEDBITS(j)
5175 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
5176 DUMPBITS(t->bits)
5177 e = (uInt)(t->exop);
5178 if (e == 0) /* literal */
5179 {
5180 c->sub.lit = t->base;
5181 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5182 "inflate: literal '%c'\n" :
5183 "inflate: literal 0x%02x\n", t->base));
5184 c->mode = LIT;
5185 break;
5186 }
5187 if (e & 16) /* length */
5188 {
5189 c->sub.copy.get = e & 15;
5190 c->len = t->base;
5191 c->mode = LENEXT;
5192 break;
5193 }
5194 if ((e & 64) == 0) /* next table */
5195 {
5196 c->sub.code.need = e;
5197 c->sub.code.tree = t + t->base;
5198 break;
5199 }
5200 if (e & 32) /* end of block */
5201 {
5202 Tracevv((stderr, "inflate: end of block\n"));
5203 c->mode = WASH;
5204 break;
5205 }
5206 c->mode = BADCODE; /* invalid code */
5207 z->msg = "invalid literal/length code";
5208 r = Z_DATA_ERROR;
5209 LEAVE
5210 case LENEXT: /* i: getting length extra (have base) */
5211 j = c->sub.copy.get;
5212 NEEDBITS(j)
5213 c->len += (uInt)b & inflate_mask[j];
5214 DUMPBITS(j)
5215 c->sub.code.need = c->dbits;
5216 c->sub.code.tree = c->dtree;
5217 Tracevv((stderr, "inflate: length %u\n", c->len));
5218 c->mode = DIST;
5219 /* FALLTHROUGH */
5220 case DIST: /* i: get distance next */
5221 j = c->sub.code.need;
5222 NEEDBITS(j)
5223 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
5224 DUMPBITS(t->bits)
5225 e = (uInt)(t->exop);
5226 if (e & 16) /* distance */
5227 {
5228 c->sub.copy.get = e & 15;
5229 c->sub.copy.dist = t->base;
5230 c->mode = DISTEXT;
5231 break;
5232 }
5233 if ((e & 64) == 0) /* next table */
5234 {
5235 c->sub.code.need = e;
5236 c->sub.code.tree = t + t->base;
5237 break;
5238 }
5239 c->mode = BADCODE; /* invalid code */
5240 z->msg = "invalid distance code";
5241 r = Z_DATA_ERROR;
5242 LEAVE
5243 case DISTEXT: /* i: getting distance extra */
5244 j = c->sub.copy.get;
5245 NEEDBITS(j)
5246 c->sub.copy.dist += (uInt)b & inflate_mask[j];
5247 DUMPBITS(j)
5248 Tracevv((stderr, "inflate: distance %u\n", c->sub.copy.dist));
5249 c->mode = COPY;
5250 /* FALLTHROUGH */
5251 case COPY: /* o: copying bytes in window, waiting for space */
5252 f = q - c->sub.copy.dist;
5253 while (f < s->window) /* modulo window size-"while" instead */
5254 f += s->end - s->window; /* of "if" handles invalid distances */
5255 while (c->len)
5256 {
5257 NEEDOUT
5258 OUTBYTE(*f++)
5259 if (f == s->end)
5260 f = s->window;
5261 c->len--;
5262 }
5263 c->mode = START;
5264 break;
5265 case LIT: /* o: got literal, waiting for output space */
5266 NEEDOUT
5267 OUTBYTE(c->sub.lit)
5268 c->mode = START;
5269 break;
5270 case WASH: /* o: got eob, possibly more output */
5271 if (k > 7) /* return unused byte, if any */
5272 {
5273 Assert(k < 16, "inflate_codes grabbed too many bytes")
5274 k -= 8;
5275 n++;
5276 p--; /* can always return one */
5277 }
5278 FLUSH
5279 if (s->read != s->write)
5280 LEAVE
5281 c->mode = END;
5282 /* FALLTHROUGH */
5283 case END:
5284 r = Z_STREAM_END;
5285 LEAVE
5286 case BADCODE: /* x: got error */
5287 r = Z_DATA_ERROR;
5288 LEAVE
5289 default:
5290 r = Z_STREAM_ERROR;
5291 LEAVE
5292 }
5293 #ifdef NEED_DUMMY_RETURN
5294 return Z_STREAM_ERROR; /* Some dumb compilers complain without this */
5295 #endif
5296 }
5297
5298
inflate_codes_free(inflate_codes_statef * c,z_streamp z)5299 void inflate_codes_free(inflate_codes_statef *c, z_streamp z)
5300 {
5301 ZFREE(z, c);
5302 Tracev((stderr, "inflate: codes free\n"));
5303 }
5304 /* --- infcodes.c */
5305
5306 /* +++ infutil.c */
5307
5308 /* inflate_util.c -- data and routines common to blocks and codes
5309 * Copyright (C) 1995-2002 Mark Adler
5310 * For conditions of distribution and use, see copyright notice in zlib.h
5311 */
5312
5313 /* #include "zutil.h" */
5314 /* #include "infblock.h" */
5315 /* #include "inftrees.h" */
5316 /* #include "infcodes.h" */
5317 /* #include "infutil.h" */
5318
5319 #ifndef NO_DUMMY_DECL
5320 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
5321 #endif
5322
5323 /* And'ing with mask[n] masks the lower n bits */
5324 uInt inflate_mask[17] = {
5325 0x0000,
5326 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
5327 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
5328 };
5329
5330
5331 /* copy as much as possible from the sliding window to the output area */
inflate_flush(inflate_blocks_statef * s,z_streamp z,int r)5332 int inflate_flush(inflate_blocks_statef *s, z_streamp z, int r)
5333 {
5334 uInt n;
5335 Bytef *p;
5336 Bytef *q;
5337
5338 /* local copies of source and destination pointers */
5339 p = z->next_out;
5340 q = s->read;
5341
5342 /* compute number of bytes to copy as far as end of window */
5343 n = (uInt)((q <= s->write ? s->write : s->end) - q);
5344 if (n > z->avail_out) n = z->avail_out;
5345 if (n && r == Z_BUF_ERROR) r = Z_OK;
5346
5347 /* update counters */
5348 z->avail_out -= n;
5349 z->total_out += n;
5350
5351 /* update check information */
5352 if (s->checkfn != Z_NULL)
5353 z->adler = s->check = (*s->checkfn)(s->check, q, n);
5354
5355 /* copy as far as end of window */
5356 if (p != Z_NULL) {
5357 zmemcpy(p, q, n);
5358 p += n;
5359 }
5360 q += n;
5361
5362 /* see if more to copy at beginning of window */
5363 if (q == s->end)
5364 {
5365 /* wrap pointers */
5366 q = s->window;
5367 if (s->write == s->end)
5368 s->write = s->window;
5369
5370 /* compute bytes to copy */
5371 n = (uInt)(s->write - q);
5372 if (n > z->avail_out) n = z->avail_out;
5373 if (n && r == Z_BUF_ERROR) r = Z_OK;
5374
5375 /* update counters */
5376 z->avail_out -= n;
5377 z->total_out += n;
5378
5379 /* update check information */
5380 if (s->checkfn != Z_NULL)
5381 z->adler = s->check = (*s->checkfn)(s->check, q, n);
5382
5383 /* copy */
5384 if (p != NULL) {
5385 zmemcpy(p, q, n);
5386 p += n;
5387 }
5388 q += n;
5389 }
5390
5391 /* update pointers */
5392 z->next_out = p;
5393 s->read = q;
5394
5395 /* done */
5396 return r;
5397 }
5398 /* --- infutil.c */
5399
5400 /* +++ inffast.c */
5401
5402 /* inffast.c -- process literals and length/distance pairs fast
5403 * Copyright (C) 1995-2002 Mark Adler
5404 * For conditions of distribution and use, see copyright notice in zlib.h
5405 */
5406
5407 /* #include "zutil.h" */
5408 /* #include "inftrees.h" */
5409 /* #include "infblock.h" */
5410 /* #include "infcodes.h" */
5411 /* #include "infutil.h" */
5412 /* #include "inffast.h" */
5413
5414 #ifndef NO_DUMMY_DECL
5415 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
5416 #endif
5417
5418 /* simplify the use of the inflate_huft type with some defines */
5419 #define exop word.what.Exop
5420 #define bits word.what.Bits
5421
5422 /* macros for bit input with no checking and for returning unused bytes */
5423 #define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}}
5424 #define UNGRAB {c=z->avail_in-n;c=(k>>3)<c?k>>3:c;n+=c;p-=c;k-=c<<3;}
5425
5426 /* Called with number of bytes left to write in window at least 258
5427 (the maximum string length) and number of input bytes available
5428 at least ten. The ten bytes are six bytes for the longest length/
5429 distance pair plus four bytes for overloading the bit buffer. */
5430
inflate_fast(uInt bl,uInt bd,inflate_huft * tl,inflate_huft * td,inflate_blocks_statef * s,z_streamp z)5431 int inflate_fast(uInt bl, uInt bd,
5432 inflate_huft *tl,
5433 inflate_huft *td,
5434 inflate_blocks_statef *s,
5435 z_streamp z)
5436 {
5437 inflate_huft *t; /* temporary pointer */
5438 uInt e; /* extra bits or operation */
5439 uLong b; /* bit buffer */
5440 uInt k; /* bits in bit buffer */
5441 Bytef *p; /* input data pointer */
5442 uInt n; /* bytes available there */
5443 Bytef *q; /* output window write pointer */
5444 uInt m; /* bytes to end of window or read pointer */
5445 uInt ml; /* mask for literal/length tree */
5446 uInt md; /* mask for distance tree */
5447 uInt c; /* bytes to copy */
5448 uInt d; /* distance back to copy from */
5449 Bytef *r; /* copy source pointer */
5450
5451 /* load input, output, bit values */
5452 LOAD
5453
5454 /* initialize masks */
5455 ml = inflate_mask[bl];
5456 md = inflate_mask[bd];
5457
5458 /* do until not enough input or output space for fast loop */
5459 do { /* assume called with m >= 258 && n >= 10 */
5460 /* get literal/length code */
5461 GRABBITS(20) /* max bits for literal/length code */
5462 if ((e = (t = tl + ((uInt)b & ml))->exop) == 0)
5463 {
5464 DUMPBITS(t->bits)
5465 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5466 "inflate: * literal '%c'\n" :
5467 "inflate: * literal 0x%02x\n", t->base));
5468 *q++ = (Byte)t->base;
5469 m--;
5470 continue;
5471 }
5472 do {
5473 DUMPBITS(t->bits)
5474 if (e & 16)
5475 {
5476 /* get extra bits for length */
5477 e &= 15;
5478 c = t->base + ((uInt)b & inflate_mask[e]);
5479 DUMPBITS(e)
5480 Tracevv((stderr, "inflate: * length %u\n", c));
5481
5482 /* decode distance base of block to copy */
5483 GRABBITS(15); /* max bits for distance code */
5484 e = (t = td + ((uInt)b & md))->exop;
5485 do {
5486 DUMPBITS(t->bits)
5487 if (e & 16)
5488 {
5489 /* get extra bits to add to distance base */
5490 e &= 15;
5491 GRABBITS(e) /* get extra bits (up to 13) */
5492 d = t->base + ((uInt)b & inflate_mask[e]);
5493 DUMPBITS(e)
5494 Tracevv((stderr, "inflate: * distance %u\n", d));
5495
5496 /* do the copy */
5497 m -= c;
5498 r = q - d;
5499 if (r < s->window) /* wrap if needed */
5500 {
5501 do {
5502 r += s->end - s->window; /* force pointer in window */
5503 } while (r < s->window); /* covers invalid distances */
5504 e = s->end - r;
5505 if (c > e)
5506 {
5507 c -= e; /* wrapped copy */
5508 do {
5509 *q++ = *r++;
5510 } while (--e);
5511 r = s->window;
5512 do {
5513 *q++ = *r++;
5514 } while (--c);
5515 }
5516 else /* normal copy */
5517 {
5518 *q++ = *r++; c--;
5519 *q++ = *r++; c--;
5520 do {
5521 *q++ = *r++;
5522 } while (--c);
5523 }
5524 }
5525 else /* normal copy */
5526 {
5527 *q++ = *r++; c--;
5528 *q++ = *r++; c--;
5529 do {
5530 *q++ = *r++;
5531 } while (--c);
5532 }
5533 break;
5534 }
5535 else if ((e & 64) == 0)
5536 {
5537 t += t->base;
5538 e = (t += ((uInt)b & inflate_mask[e]))->exop;
5539 }
5540 else
5541 {
5542 z->msg = "invalid distance code";
5543 UNGRAB
5544 UPDATE
5545 return Z_DATA_ERROR;
5546 }
5547 } while (1);
5548 break;
5549 }
5550 if ((e & 64) == 0)
5551 {
5552 t += t->base;
5553 if ((e = (t += ((uInt)b & inflate_mask[e]))->exop) == 0)
5554 {
5555 DUMPBITS(t->bits)
5556 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5557 "inflate: * literal '%c'\n" :
5558 "inflate: * literal 0x%02x\n", t->base));
5559 *q++ = (Byte)t->base;
5560 m--;
5561 break;
5562 }
5563 }
5564 else if (e & 32)
5565 {
5566 Tracevv((stderr, "inflate: * end of block\n"));
5567 UNGRAB
5568 UPDATE
5569 return Z_STREAM_END;
5570 }
5571 else
5572 {
5573 z->msg = "invalid literal/length code";
5574 UNGRAB
5575 UPDATE
5576 return Z_DATA_ERROR;
5577 }
5578 } while (1);
5579 } while (m >= 258 && n >= 10);
5580
5581 /* not enough input or output--restore pointers and return */
5582 UNGRAB
5583 UPDATE
5584 return Z_OK;
5585 }
5586 /* --- inffast.c */
5587
5588 /* +++ zutil.c */
5589
5590 /* zutil.c -- target dependent utility functions for the compression library
5591 * Copyright (C) 1995-2002 Jean-loup Gailly.
5592 * For conditions of distribution and use, see copyright notice in zlib.h
5593 */
5594
5595 /* @(#) Id */
5596
5597 #ifdef DEBUG_ZLIB
5598 #include <stdio.h>
5599 #endif
5600
5601 /* #include "zutil.h" */
5602
5603 #ifndef NO_DUMMY_DECL
5604 struct internal_state {int dummy;}; /* for buggy compilers */
5605 #endif
5606
5607 #ifndef STDC
5608 extern void exit(int);
5609 #endif
5610
5611 const char *z_errmsg[10] = {
5612 "need dictionary", /* Z_NEED_DICT 2 */
5613 "stream end", /* Z_STREAM_END 1 */
5614 "", /* Z_OK 0 */
5615 "file error", /* Z_ERRNO (-1) */
5616 "stream error", /* Z_STREAM_ERROR (-2) */
5617 "data error", /* Z_DATA_ERROR (-3) */
5618 "insufficient memory", /* Z_MEM_ERROR (-4) */
5619 "buffer error", /* Z_BUF_ERROR (-5) */
5620 "incompatible version",/* Z_VERSION_ERROR (-6) */
5621 ""};
5622
5623
5624 #if 0
5625 const char * ZEXPORT zlibVersion()
5626 {
5627 return ZLIB_VERSION;
5628 }
5629 #endif
5630
5631 #ifdef DEBUG_ZLIB
5632
5633 # ifndef verbose
5634 # define verbose 0
5635 # endif
5636 int z_verbose = verbose;
5637
z_error(m)5638 void z_error (m)
5639 char *m;
5640 {
5641 fprintf(stderr, "%s\n", m);
5642 exit(1);
5643 }
5644 #endif
5645
5646 /* exported to allow conversion of error code to string for compress() and
5647 * uncompress()
5648 */
5649 #if 0
5650 const char * ZEXPORT zError(err)
5651 int err;
5652 {
5653 return ERR_MSG(err);
5654 }
5655 #endif
5656
5657
5658 #ifndef HAVE_MEMCPY
5659
zmemcpy(dest,source,len)5660 void zmemcpy(dest, source, len)
5661 Bytef* dest;
5662 const Bytef* source;
5663 uInt len;
5664 {
5665 if (len == 0) return;
5666 do {
5667 *dest++ = *source++; /* ??? to be unrolled */
5668 } while (--len != 0);
5669 }
5670
zmemcmp(s1,s2,len)5671 int zmemcmp(s1, s2, len)
5672 const Bytef* s1;
5673 const Bytef* s2;
5674 uInt len;
5675 {
5676 uInt j;
5677
5678 for (j = 0; j < len; j++) {
5679 if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1;
5680 }
5681 return 0;
5682 }
5683
zmemzero(dest,len)5684 void zmemzero(dest, len)
5685 Bytef* dest;
5686 uInt len;
5687 {
5688 if (len == 0) return;
5689 do {
5690 *dest++ = 0; /* ??? to be unrolled */
5691 } while (--len != 0);
5692 }
5693 #endif
5694
5695 #ifdef __TURBOC__
5696 #if (defined( __BORLANDC__) || !defined(SMALL_MEDIUM)) && !defined(__32BIT__)
5697 /* Small and medium model in Turbo C are for now limited to near allocation
5698 * with reduced MAX_WBITS and MAX_MEM_LEVEL
5699 */
5700 # define MY_ZCALLOC
5701
5702 /* Turbo C malloc() does not allow dynamic allocation of 64K bytes
5703 * and farmalloc(64K) returns a pointer with an offset of 8, so we
5704 * must fix the pointer. Warning: the pointer must be put back to its
5705 * original form in order to free it, use zcfree().
5706 */
5707
5708 #define MAX_PTR 10
5709 /* 10*64K = 640K */
5710
5711 local int next_ptr = 0;
5712
5713 typedef struct ptr_table_s {
5714 voidpf org_ptr;
5715 voidpf new_ptr;
5716 } ptr_table;
5717
5718 local ptr_table table[MAX_PTR];
5719 /* This table is used to remember the original form of pointers
5720 * to large buffers (64K). Such pointers are normalized with a zero offset.
5721 * Since MSDOS is not a preemptive multitasking OS, this table is not
5722 * protected from concurrent access. This hack doesn't work anyway on
5723 * a protected system like OS/2. Use Microsoft C instead.
5724 */
5725
zcalloc(voidpf opaque,unsigned items,unsigned size)5726 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
5727 {
5728 voidpf buf = opaque; /* just to make some compilers happy */
5729 ulg bsize = (ulg)items*size;
5730
5731 /* If we allocate less than 65520 bytes, we assume that farmalloc
5732 * will return a usable pointer which doesn't have to be normalized.
5733 */
5734 if (bsize < 65520L) {
5735 buf = farmalloc(bsize);
5736 if (*(ush*)&buf != 0) return buf;
5737 } else {
5738 buf = farmalloc(bsize + 16L);
5739 }
5740 if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
5741 table[next_ptr].org_ptr = buf;
5742
5743 /* Normalize the pointer to seg:0 */
5744 *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
5745 *(ush*)&buf = 0;
5746 table[next_ptr++].new_ptr = buf;
5747 return buf;
5748 }
5749
zcfree(voidpf opaque,voidpf ptr)5750 void zcfree (voidpf opaque, voidpf ptr)
5751 {
5752 int n;
5753 if (*(ush*)&ptr != 0) { /* object < 64K */
5754 farfree(ptr);
5755 return;
5756 }
5757 /* Find the original pointer */
5758 for (n = 0; n < next_ptr; n++) {
5759 if (ptr != table[n].new_ptr) continue;
5760
5761 farfree(table[n].org_ptr);
5762 while (++n < next_ptr) {
5763 table[n-1] = table[n];
5764 }
5765 next_ptr--;
5766 return;
5767 }
5768 ptr = opaque; /* just to make some compilers happy */
5769 Assert(0, "zcfree: ptr not found");
5770 }
5771 #endif
5772 #endif /* __TURBOC__ */
5773
5774
5775 #if defined(M_I86) && !defined(__32BIT__)
5776 /* Microsoft C in 16-bit mode */
5777
5778 # define MY_ZCALLOC
5779
5780 #if (!defined(_MSC_VER) || (_MSC_VER <= 600))
5781 # define _halloc halloc
5782 # define _hfree hfree
5783 #endif
5784
zcalloc(voidpf opaque,unsigned items,unsigned size)5785 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
5786 {
5787 if (opaque) opaque = 0; /* to make compiler happy */
5788 return _halloc((long)items, size);
5789 }
5790
zcfree(voidpf opaque,voidpf ptr)5791 void zcfree (voidpf opaque, voidpf ptr)
5792 {
5793 if (opaque) opaque = 0; /* to make compiler happy */
5794 _hfree(ptr);
5795 }
5796
5797 #endif /* MSC */
5798
5799
5800 #ifndef MY_ZCALLOC /* Any system without a special alloc function */
5801
5802 #ifndef STDC
5803 extern voidp calloc(uInt items, uInt size);
5804 extern void free(voidpf ptr);
5805 #endif
5806
zcalloc(opaque,items,size)5807 voidpf zcalloc (opaque, items, size)
5808 voidpf opaque;
5809 unsigned items;
5810 unsigned size;
5811 {
5812 if (opaque) items += size - size; /* make compiler happy */
5813 return (voidpf)calloc(items, size);
5814 }
5815
zcfree(opaque,ptr)5816 void zcfree (opaque, ptr)
5817 voidpf opaque;
5818 voidpf ptr;
5819 {
5820 free(ptr);
5821 if (opaque) return; /* make compiler happy */
5822 }
5823
5824 #endif /* MY_ZCALLOC */
5825 /* --- zutil.c */
5826
5827 /* +++ adler32.c */
5828 /* adler32.c -- compute the Adler-32 checksum of a data stream
5829 * Copyright (C) 1995-2002 Mark Adler
5830 * For conditions of distribution and use, see copyright notice in zlib.h
5831 */
5832
5833 /* @(#) $Id: zlib.c,v 1.39 2024/07/04 01:10:17 rin Exp $ */
5834
5835 /* #include "zlib.h" */
5836
5837 #define BASE 65521L /* largest prime smaller than 65536 */
5838 #define NMAX 5552
5839 /* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
5840
5841 #define DO1(buf,i) {s1 += buf[i]; s2 += s1;}
5842 #define DO2(buf,i) DO1(buf,i); DO1(buf,i+1);
5843 #define DO4(buf,i) DO2(buf,i); DO2(buf,i+2);
5844 #define DO8(buf,i) DO4(buf,i); DO4(buf,i+4);
5845 #define DO16(buf) DO8(buf,0); DO8(buf,8);
5846
5847 /* ========================================================================= */
adler32(uLong adler,const Bytef * buf,uInt len)5848 uLong ZEXPORT adler32(uLong adler, const Bytef *buf, uInt len)
5849 {
5850 unsigned long s1 = adler & 0xffff;
5851 unsigned long s2 = (adler >> 16) & 0xffff;
5852 int k;
5853
5854 if (buf == Z_NULL) return 1L;
5855
5856 while (len > 0) {
5857 k = len < NMAX ? len : NMAX;
5858 len -= k;
5859 while (k >= 16) {
5860 DO16(buf);
5861 buf += 16;
5862 k -= 16;
5863 }
5864 if (k != 0) do {
5865 s1 += *buf++;
5866 s2 += s1;
5867 } while (--k);
5868 s1 %= BASE;
5869 s2 %= BASE;
5870 }
5871 return (s2 << 16) | s1;
5872 }
5873 /* --- adler32.c */
5874
5875 #if defined(_KERNEL)
5876
5877 /*
5878 * NetBSD module glue - this code is required for the vnd and swcrypto
5879 * pseudo-devices.
5880 */
5881 #include <sys/module.h>
5882
5883 static int zlib_modcmd(modcmd_t, void *);
5884
5885 MODULE(MODULE_CLASS_MISC, zlib, NULL);
5886
5887 static int
zlib_modcmd(modcmd_t cmd,void * arg)5888 zlib_modcmd(modcmd_t cmd, void *arg)
5889 {
5890
5891 switch (cmd) {
5892 case MODULE_CMD_INIT:
5893 case MODULE_CMD_FINI:
5894 return 0;
5895 case MODULE_CMD_STAT:
5896 case MODULE_CMD_AUTOUNLOAD:
5897 default:
5898 return ENOTTY;
5899 }
5900 }
5901
5902 #endif /* defined(_KERNEL) */
5903