zlib.c revision 1.27 1 1.27 christos /* $NetBSD: zlib.c,v 1.27 2006/10/12 01:32:30 christos Exp $ */
2 1.1 paulus /*
3 1.7 christos * This file is derived from various .h and .c files from the zlib-1.0.4
4 1.1 paulus * distribution by Jean-loup Gailly and Mark Adler, with some additions
5 1.1 paulus * by Paul Mackerras to aid in implementing Deflate compression and
6 1.1 paulus * decompression for PPP packets. See zlib.h for conditions of
7 1.1 paulus * distribution and use.
8 1.1 paulus *
9 1.1 paulus * Changes that have been made include:
10 1.1 paulus * - added Z_PACKET_FLUSH (see zlib.h for details)
11 1.7 christos * - added inflateIncomp and deflateOutputPending
12 1.7 christos * - allow strm->next_out to be NULL, meaning discard the output
13 1.4 christos *
14 1.27 christos * $Id: zlib.c,v 1.27 2006/10/12 01:32:30 christos Exp $
15 1.1 paulus */
16 1.1 paulus
17 1.20 perry /*
18 1.17 fvdl * ==FILEVERSION 020312==
19 1.4 christos *
20 1.4 christos * This marker is used by the Linux installation script to determine
21 1.4 christos * whether an up-to-date version of this file is already installed.
22 1.4 christos */
23 1.15 lukem
24 1.15 lukem #include <sys/cdefs.h>
25 1.27 christos __KERNEL_RCSID(0, "$NetBSD: zlib.c,v 1.27 2006/10/12 01:32:30 christos Exp $");
26 1.1 paulus
27 1.7 christos #define NO_DUMMY_DECL
28 1.7 christos #define NO_ZCFUNCS
29 1.7 christos #define MY_ZCALLOC
30 1.7 christos
31 1.7 christos #if defined(__FreeBSD__) && (defined(KERNEL) || defined(_KERNEL))
32 1.7 christos #define inflate inflate_ppp /* FreeBSD already has an inflate :-( */
33 1.7 christos #endif
34 1.7 christos
35 1.7 christos
36 1.7 christos /* +++ zutil.h */
37 1.17 fvdl
38 1.1 paulus /* zutil.h -- internal interface and configuration of the compression library
39 1.17 fvdl * Copyright (C) 1995-2002 Jean-loup Gailly.
40 1.1 paulus * For conditions of distribution and use, see copyright notice in zlib.h
41 1.1 paulus */
42 1.1 paulus
43 1.1 paulus /* WARNING: this file should *not* be used by applications. It is
44 1.1 paulus part of the implementation of the compression library and is
45 1.1 paulus subject to change. Applications should only use zlib.h.
46 1.1 paulus */
47 1.1 paulus
48 1.27 christos /* @(#) $Id: zlib.c,v 1.27 2006/10/12 01:32:30 christos Exp $ */
49 1.1 paulus
50 1.7 christos #ifndef _Z_UTIL_H
51 1.1 paulus #define _Z_UTIL_H
52 1.1 paulus
53 1.1 paulus #include "zlib.h"
54 1.1 paulus
55 1.7 christos #if defined(KERNEL) || defined(_KERNEL)
56 1.7 christos /* Assume this is a *BSD or SVR4 kernel */
57 1.9 ragge #include <sys/param.h>
58 1.7 christos #include <sys/time.h>
59 1.7 christos #include <sys/systm.h>
60 1.7 christos # define HAVE_MEMCPY
61 1.7 christos #else
62 1.7 christos #if defined(__KERNEL__)
63 1.7 christos /* Assume this is a Linux kernel */
64 1.7 christos #include <linux/string.h>
65 1.7 christos #define HAVE_MEMCPY
66 1.7 christos
67 1.7 christos #else /* not kernel */
68 1.7 christos
69 1.17 fvdl #if defined(__NetBSD__) && (defined(_KERNEL) || defined(_STANDALONE))
70 1.17 fvdl
71 1.17 fvdl /* XXX doesn't seem to need anything at all, but this is for consistency. */
72 1.17 fvdl # include <lib/libkern/libkern.h>
73 1.17 fvdl
74 1.7 christos #else
75 1.23 christos # include <sys/types.h>
76 1.23 christos # include <sys/param.h>
77 1.7 christos #ifdef STDC
78 1.17 fvdl # include <stddef.h>
79 1.7 christos # include <string.h>
80 1.7 christos # include <stdlib.h>
81 1.7 christos #endif
82 1.17 fvdl #ifdef NO_ERRNO_H
83 1.17 fvdl extern int errno;
84 1.17 fvdl #else
85 1.17 fvdl # include <errno.h>
86 1.17 fvdl #endif
87 1.17 fvdl #endif /* __NetBSD__ && _STANDALONE */
88 1.7 christos #endif /* __KERNEL__ */
89 1.7 christos #endif /* _KERNEL || KERNEL */
90 1.7 christos
91 1.1 paulus #ifndef local
92 1.1 paulus # define local static
93 1.1 paulus #endif
94 1.1 paulus /* compile with -Dlocal if your debugger can't find static symbols */
95 1.1 paulus
96 1.1 paulus typedef unsigned char uch;
97 1.1 paulus typedef uch FAR uchf;
98 1.1 paulus typedef unsigned short ush;
99 1.1 paulus typedef ush FAR ushf;
100 1.1 paulus typedef unsigned long ulg;
101 1.1 paulus
102 1.17 fvdl extern const char *z_errmsg[10]; /* indexed by 2-zlib_error */
103 1.7 christos /* (size given to avoid silly warnings with Visual C++) */
104 1.1 paulus
105 1.7 christos #define ERR_MSG(err) z_errmsg[Z_NEED_DICT-(err)]
106 1.7 christos
107 1.7 christos #define ERR_RETURN(strm,err) \
108 1.21 christos return (strm->msg = ERR_MSG(err), (err))
109 1.1 paulus /* To be used only when the state is known to be valid */
110 1.1 paulus
111 1.1 paulus /* common constants */
112 1.1 paulus
113 1.1 paulus #ifndef DEF_WBITS
114 1.1 paulus # define DEF_WBITS MAX_WBITS
115 1.1 paulus #endif
116 1.1 paulus /* default windowBits for decompression. MAX_WBITS is for compression only */
117 1.1 paulus
118 1.1 paulus #if MAX_MEM_LEVEL >= 8
119 1.1 paulus # define DEF_MEM_LEVEL 8
120 1.1 paulus #else
121 1.1 paulus # define DEF_MEM_LEVEL MAX_MEM_LEVEL
122 1.1 paulus #endif
123 1.1 paulus /* default memLevel */
124 1.1 paulus
125 1.1 paulus #define STORED_BLOCK 0
126 1.1 paulus #define STATIC_TREES 1
127 1.1 paulus #define DYN_TREES 2
128 1.1 paulus /* The three kinds of block type */
129 1.1 paulus
130 1.1 paulus #define MIN_MATCH 3
131 1.1 paulus #define MAX_MATCH 258
132 1.1 paulus /* The minimum and maximum match lengths */
133 1.1 paulus
134 1.7 christos #define PRESET_DICT 0x20 /* preset dictionary flag in zlib header */
135 1.7 christos
136 1.7 christos /* target dependencies */
137 1.7 christos
138 1.7 christos #ifdef MSDOS
139 1.7 christos # define OS_CODE 0x00
140 1.17 fvdl # if defined(__TURBOC__) || defined(__BORLANDC__)
141 1.17 fvdl # if(__STDC__ == 1) && (defined(__LARGE__) || defined(__COMPACT__))
142 1.17 fvdl /* Allow compilation with ANSI keywords only enabled */
143 1.17 fvdl void _Cdecl farfree( void *block );
144 1.17 fvdl void *_Cdecl farmalloc( unsigned long nbytes );
145 1.17 fvdl # else
146 1.17 fvdl # include <alloc.h>
147 1.17 fvdl # endif
148 1.7 christos # else /* MSC or DJGPP */
149 1.7 christos # include <malloc.h>
150 1.7 christos # endif
151 1.7 christos #endif
152 1.7 christos
153 1.7 christos #ifdef OS2
154 1.7 christos # define OS_CODE 0x06
155 1.7 christos #endif
156 1.7 christos
157 1.7 christos #ifdef WIN32 /* Window 95 & Windows NT */
158 1.7 christos # define OS_CODE 0x0b
159 1.7 christos #endif
160 1.7 christos
161 1.7 christos #if defined(VAXC) || defined(VMS)
162 1.7 christos # define OS_CODE 0x02
163 1.17 fvdl # define F_OPEN(name, mode) \
164 1.7 christos fopen((name), (mode), "mbc=60", "ctx=stm", "rfm=fix", "mrs=512")
165 1.7 christos #endif
166 1.7 christos
167 1.7 christos #ifdef AMIGA
168 1.7 christos # define OS_CODE 0x01
169 1.7 christos #endif
170 1.7 christos
171 1.7 christos #if defined(ATARI) || defined(atarist)
172 1.7 christos # define OS_CODE 0x05
173 1.7 christos #endif
174 1.7 christos
175 1.17 fvdl #if defined(MACOS) || defined(TARGET_OS_MAC)
176 1.7 christos # define OS_CODE 0x07
177 1.17 fvdl # if defined(__MWERKS__) && __dest_os != __be_os && __dest_os != __win32_os
178 1.17 fvdl # include <unix.h> /* for fdopen */
179 1.17 fvdl # else
180 1.17 fvdl # ifndef fdopen
181 1.17 fvdl # define fdopen(fd,mode) NULL /* No fdopen() */
182 1.17 fvdl # endif
183 1.17 fvdl # endif
184 1.7 christos #endif
185 1.7 christos
186 1.7 christos #ifdef __50SERIES /* Prime/PRIMOS */
187 1.7 christos # define OS_CODE 0x0F
188 1.7 christos #endif
189 1.7 christos
190 1.7 christos #ifdef TOPS20
191 1.7 christos # define OS_CODE 0x0a
192 1.7 christos #endif
193 1.7 christos
194 1.7 christos #if defined(_BEOS_) || defined(RISCOS)
195 1.7 christos # define fdopen(fd,mode) NULL /* No fdopen() */
196 1.7 christos #endif
197 1.7 christos
198 1.17 fvdl #if (defined(_MSC_VER) && (_MSC_VER > 600))
199 1.17 fvdl # define fdopen(fd,type) _fdopen(fd,type)
200 1.17 fvdl #endif
201 1.17 fvdl
202 1.17 fvdl
203 1.7 christos /* Common defaults */
204 1.7 christos
205 1.7 christos #ifndef OS_CODE
206 1.7 christos # define OS_CODE 0x03 /* assume Unix */
207 1.7 christos #endif
208 1.7 christos
209 1.17 fvdl #ifndef F_OPEN
210 1.17 fvdl # define F_OPEN(name, mode) fopen((name), (mode))
211 1.7 christos #endif
212 1.7 christos
213 1.1 paulus /* functions */
214 1.1 paulus
215 1.7 christos #ifdef HAVE_STRERROR
216 1.17 fvdl extern char *strerror __P((int));
217 1.7 christos # define zstrerror(errnum) strerror(errnum)
218 1.1 paulus #else
219 1.7 christos # define zstrerror(errnum) ""
220 1.7 christos #endif
221 1.4 christos
222 1.7 christos #if defined(pyr)
223 1.7 christos # define NO_MEMCPY
224 1.7 christos #endif
225 1.17 fvdl #if defined(SMALL_MEDIUM) && !defined(_MSC_VER) && !defined(__SC__)
226 1.7 christos /* Use our own functions for small and medium model with MSC <= 5.0.
227 1.7 christos * You may have to use the same strategy for Borland C (untested).
228 1.17 fvdl * The __SC__ check is for Symantec.
229 1.7 christos */
230 1.7 christos # define NO_MEMCPY
231 1.7 christos #endif
232 1.1 paulus #if defined(STDC) && !defined(HAVE_MEMCPY) && !defined(NO_MEMCPY)
233 1.1 paulus # define HAVE_MEMCPY
234 1.1 paulus #endif
235 1.1 paulus #ifdef HAVE_MEMCPY
236 1.7 christos # ifdef SMALL_MEDIUM /* MSDOS small or medium model */
237 1.7 christos # define zmemcpy _fmemcpy
238 1.7 christos # define zmemcmp _fmemcmp
239 1.7 christos # define zmemzero(dest, len) _fmemset(dest, 0, len)
240 1.7 christos # else
241 1.1 paulus # define zmemcpy memcpy
242 1.7 christos # define zmemcmp memcmp
243 1.1 paulus # define zmemzero(dest, len) memset(dest, 0, len)
244 1.7 christos # endif
245 1.1 paulus #else
246 1.17 fvdl extern void zmemcpy __P((Bytef* dest, const Bytef* source, uInt len));
247 1.17 fvdl extern int zmemcmp __P((const Bytef* s1, const Bytef* s2, uInt len));
248 1.17 fvdl extern void zmemzero __P((Bytef* dest, uInt len));
249 1.1 paulus #endif
250 1.1 paulus
251 1.1 paulus /* Diagnostic functions */
252 1.17 fvdl #if defined(DEBUG_ZLIB) && !defined(_KERNEL) && !defined(_STANDALONE)
253 1.1 paulus # include <stdio.h>
254 1.17 fvdl extern int z_verbose;
255 1.17 fvdl extern void z_error __P((char *m));
256 1.1 paulus # define Assert(cond,msg) {if(!(cond)) z_error(msg);}
257 1.17 fvdl # define Trace(x) {if (z_verbose>=0) fprintf x ;}
258 1.17 fvdl # define Tracev(x) {if (z_verbose>0) fprintf x ;}
259 1.17 fvdl # define Tracevv(x) {if (z_verbose>1) fprintf x ;}
260 1.17 fvdl # define Tracec(c,x) {if (z_verbose>0 && (c)) fprintf x ;}
261 1.17 fvdl # define Tracecv(c,x) {if (z_verbose>1 && (c)) fprintf x ;}
262 1.1 paulus #else
263 1.1 paulus # define Assert(cond,msg)
264 1.1 paulus # define Trace(x)
265 1.1 paulus # define Tracev(x)
266 1.1 paulus # define Tracevv(x)
267 1.1 paulus # define Tracec(c,x)
268 1.1 paulus # define Tracecv(c,x)
269 1.1 paulus #endif
270 1.1 paulus
271 1.1 paulus
272 1.17 fvdl typedef uLong (ZEXPORT *check_func) __P((uLong check, const Bytef *buf,
273 1.17 fvdl uInt len));
274 1.17 fvdl voidpf zcalloc __P((voidpf opaque, unsigned items, unsigned size));
275 1.17 fvdl void zcfree __P((voidpf opaque, voidpf ptr));
276 1.1 paulus
277 1.1 paulus #define ZALLOC(strm, items, size) \
278 1.1 paulus (*((strm)->zalloc))((strm)->opaque, (items), (size))
279 1.7 christos #define ZFREE(strm, addr) (*((strm)->zfree))((strm)->opaque, (voidpf)(addr))
280 1.7 christos #define TRY_FREE(s, p) {if (p) ZFREE(s, p);}
281 1.7 christos
282 1.7 christos #endif /* _Z_UTIL_H */
283 1.7 christos /* --- zutil.h */
284 1.1 paulus
285 1.7 christos /* +++ deflate.h */
286 1.17 fvdl
287 1.1 paulus /* deflate.h -- internal compression state
288 1.17 fvdl * Copyright (C) 1995-2002 Jean-loup Gailly
289 1.20 perry * For conditions of distribution and use, see copyright notice in zlib.h
290 1.1 paulus */
291 1.1 paulus
292 1.1 paulus /* WARNING: this file should *not* be used by applications. It is
293 1.1 paulus part of the implementation of the compression library and is
294 1.1 paulus subject to change. Applications should only use zlib.h.
295 1.1 paulus */
296 1.1 paulus
297 1.27 christos /* @(#) $Id: zlib.c,v 1.27 2006/10/12 01:32:30 christos Exp $ */
298 1.1 paulus
299 1.7 christos #ifndef _DEFLATE_H
300 1.7 christos #define _DEFLATE_H
301 1.7 christos
302 1.7 christos /* #include "zutil.h" */
303 1.1 paulus
304 1.1 paulus /* ===========================================================================
305 1.1 paulus * Internal compression state.
306 1.1 paulus */
307 1.1 paulus
308 1.1 paulus #define LENGTH_CODES 29
309 1.1 paulus /* number of length codes, not counting the special END_BLOCK code */
310 1.1 paulus
311 1.1 paulus #define LITERALS 256
312 1.1 paulus /* number of literal bytes 0..255 */
313 1.1 paulus
314 1.1 paulus #define L_CODES (LITERALS+1+LENGTH_CODES)
315 1.1 paulus /* number of Literal or Length codes, including the END_BLOCK code */
316 1.1 paulus
317 1.1 paulus #define D_CODES 30
318 1.1 paulus /* number of distance codes */
319 1.1 paulus
320 1.1 paulus #define BL_CODES 19
321 1.1 paulus /* number of codes used to transfer the bit lengths */
322 1.1 paulus
323 1.1 paulus #define HEAP_SIZE (2*L_CODES+1)
324 1.1 paulus /* maximum heap size */
325 1.1 paulus
326 1.1 paulus #define MAX_BITS 15
327 1.1 paulus /* All codes must not exceed MAX_BITS bits */
328 1.1 paulus
329 1.1 paulus #define INIT_STATE 42
330 1.1 paulus #define BUSY_STATE 113
331 1.1 paulus #define FINISH_STATE 666
332 1.1 paulus /* Stream status */
333 1.1 paulus
334 1.1 paulus
335 1.1 paulus /* Data structure describing a single value and its code string. */
336 1.1 paulus typedef struct ct_data_s {
337 1.1 paulus union {
338 1.1 paulus ush freq; /* frequency count */
339 1.1 paulus ush code; /* bit string */
340 1.1 paulus } fc;
341 1.1 paulus union {
342 1.1 paulus ush dad; /* father node in Huffman tree */
343 1.1 paulus ush len; /* length of bit string */
344 1.1 paulus } dl;
345 1.1 paulus } FAR ct_data;
346 1.1 paulus
347 1.1 paulus #define Freq fc.freq
348 1.1 paulus #define Code fc.code
349 1.1 paulus #define Dad dl.dad
350 1.1 paulus #define Len dl.len
351 1.1 paulus
352 1.1 paulus typedef struct static_tree_desc_s static_tree_desc;
353 1.1 paulus
354 1.1 paulus typedef struct tree_desc_s {
355 1.1 paulus ct_data *dyn_tree; /* the dynamic tree */
356 1.1 paulus int max_code; /* largest code with non zero frequency */
357 1.1 paulus static_tree_desc *stat_desc; /* the corresponding static tree */
358 1.1 paulus } FAR tree_desc;
359 1.1 paulus
360 1.1 paulus typedef ush Pos;
361 1.1 paulus typedef Pos FAR Posf;
362 1.1 paulus typedef unsigned IPos;
363 1.1 paulus
364 1.1 paulus /* A Pos is an index in the character window. We use short instead of int to
365 1.1 paulus * save space in the various tables. IPos is used only for parameter passing.
366 1.1 paulus */
367 1.1 paulus
368 1.1 paulus typedef struct deflate_state {
369 1.7 christos z_streamp strm; /* pointer back to this zlib stream */
370 1.1 paulus int status; /* as the name implies */
371 1.1 paulus Bytef *pending_buf; /* output still pending */
372 1.7 christos ulg pending_buf_size; /* size of pending_buf */
373 1.1 paulus Bytef *pending_out; /* next pending byte to output to the stream */
374 1.1 paulus int pending; /* nb of bytes in the pending buffer */
375 1.1 paulus int noheader; /* suppress zlib header and adler32 */
376 1.7 christos Byte data_type; /* UNKNOWN, BINARY or ASCII */
377 1.1 paulus Byte method; /* STORED (for zip only) or DEFLATED */
378 1.7 christos int last_flush; /* value of flush param for previous deflate call */
379 1.1 paulus
380 1.1 paulus /* used by deflate.c: */
381 1.1 paulus
382 1.1 paulus uInt w_size; /* LZ77 window size (32K by default) */
383 1.1 paulus uInt w_bits; /* log2(w_size) (8..16) */
384 1.1 paulus uInt w_mask; /* w_size - 1 */
385 1.1 paulus
386 1.1 paulus Bytef *window;
387 1.1 paulus /* Sliding window. Input bytes are read into the second half of the window,
388 1.1 paulus * and move to the first half later to keep a dictionary of at least wSize
389 1.1 paulus * bytes. With this organization, matches are limited to a distance of
390 1.1 paulus * wSize-MAX_MATCH bytes, but this ensures that IO is always
391 1.1 paulus * performed with a length multiple of the block size. Also, it limits
392 1.1 paulus * the window size to 64K, which is quite useful on MSDOS.
393 1.1 paulus * To do: use the user input buffer as sliding window.
394 1.1 paulus */
395 1.1 paulus
396 1.1 paulus ulg window_size;
397 1.1 paulus /* Actual size of window: 2*wSize, except when the user input buffer
398 1.1 paulus * is directly used as sliding window.
399 1.1 paulus */
400 1.1 paulus
401 1.1 paulus Posf *prev;
402 1.1 paulus /* Link to older string with same hash index. To limit the size of this
403 1.1 paulus * array to 64K, this link is maintained only for the last 32K strings.
404 1.1 paulus * An index in this array is thus a window index modulo 32K.
405 1.1 paulus */
406 1.1 paulus
407 1.1 paulus Posf *head; /* Heads of the hash chains or NIL. */
408 1.1 paulus
409 1.1 paulus uInt ins_h; /* hash index of string to be inserted */
410 1.1 paulus uInt hash_size; /* number of elements in hash table */
411 1.1 paulus uInt hash_bits; /* log2(hash_size) */
412 1.1 paulus uInt hash_mask; /* hash_size-1 */
413 1.1 paulus
414 1.1 paulus uInt hash_shift;
415 1.1 paulus /* Number of bits by which ins_h must be shifted at each input
416 1.1 paulus * step. It must be such that after MIN_MATCH steps, the oldest
417 1.1 paulus * byte no longer takes part in the hash key, that is:
418 1.1 paulus * hash_shift * MIN_MATCH >= hash_bits
419 1.1 paulus */
420 1.1 paulus
421 1.1 paulus long block_start;
422 1.1 paulus /* Window position at the beginning of the current output block. Gets
423 1.1 paulus * negative when the window is moved backwards.
424 1.1 paulus */
425 1.1 paulus
426 1.1 paulus uInt match_length; /* length of best match */
427 1.1 paulus IPos prev_match; /* previous match */
428 1.1 paulus int match_available; /* set if previous match exists */
429 1.1 paulus uInt strstart; /* start of string to insert */
430 1.1 paulus uInt match_start; /* start of matching string */
431 1.1 paulus uInt lookahead; /* number of valid bytes ahead in window */
432 1.1 paulus
433 1.1 paulus uInt prev_length;
434 1.1 paulus /* Length of the best match at previous step. Matches not greater than this
435 1.1 paulus * are discarded. This is used in the lazy match evaluation.
436 1.1 paulus */
437 1.1 paulus
438 1.1 paulus uInt max_chain_length;
439 1.1 paulus /* To speed up deflation, hash chains are never searched beyond this
440 1.1 paulus * length. A higher limit improves compression ratio but degrades the
441 1.1 paulus * speed.
442 1.1 paulus */
443 1.1 paulus
444 1.1 paulus uInt max_lazy_match;
445 1.1 paulus /* Attempt to find a better match only when the current match is strictly
446 1.1 paulus * smaller than this value. This mechanism is used only for compression
447 1.1 paulus * levels >= 4.
448 1.1 paulus */
449 1.1 paulus # define max_insert_length max_lazy_match
450 1.1 paulus /* Insert new strings in the hash table only if the match length is not
451 1.1 paulus * greater than this length. This saves time but degrades compression.
452 1.1 paulus * max_insert_length is used only for compression levels <= 3.
453 1.1 paulus */
454 1.1 paulus
455 1.1 paulus int level; /* compression level (1..9) */
456 1.1 paulus int strategy; /* favor or force Huffman coding*/
457 1.1 paulus
458 1.1 paulus uInt good_match;
459 1.1 paulus /* Use a faster search when the previous match is longer than this */
460 1.1 paulus
461 1.7 christos int nice_match; /* Stop searching when current match exceeds this */
462 1.1 paulus
463 1.1 paulus /* used by trees.c: */
464 1.1 paulus /* Didn't use ct_data typedef below to supress compiler warning */
465 1.1 paulus struct ct_data_s dyn_ltree[HEAP_SIZE]; /* literal and length tree */
466 1.1 paulus struct ct_data_s dyn_dtree[2*D_CODES+1]; /* distance tree */
467 1.1 paulus struct ct_data_s bl_tree[2*BL_CODES+1]; /* Huffman tree for bit lengths */
468 1.1 paulus
469 1.1 paulus struct tree_desc_s l_desc; /* desc. for literal tree */
470 1.1 paulus struct tree_desc_s d_desc; /* desc. for distance tree */
471 1.1 paulus struct tree_desc_s bl_desc; /* desc. for bit length tree */
472 1.1 paulus
473 1.1 paulus ush bl_count[MAX_BITS+1];
474 1.1 paulus /* number of codes at each bit length for an optimal tree */
475 1.1 paulus
476 1.1 paulus int heap[2*L_CODES+1]; /* heap used to build the Huffman trees */
477 1.1 paulus int heap_len; /* number of elements in the heap */
478 1.1 paulus int heap_max; /* element of largest frequency */
479 1.1 paulus /* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used.
480 1.1 paulus * The same heap array is used to build all trees.
481 1.1 paulus */
482 1.1 paulus
483 1.1 paulus uch depth[2*L_CODES+1];
484 1.1 paulus /* Depth of each subtree used as tie breaker for trees of equal frequency
485 1.1 paulus */
486 1.1 paulus
487 1.1 paulus uchf *l_buf; /* buffer for literals or lengths */
488 1.1 paulus
489 1.1 paulus uInt lit_bufsize;
490 1.1 paulus /* Size of match buffer for literals/lengths. There are 4 reasons for
491 1.1 paulus * limiting lit_bufsize to 64K:
492 1.1 paulus * - frequencies can be kept in 16 bit counters
493 1.1 paulus * - if compression is not successful for the first block, all input
494 1.1 paulus * data is still in the window so we can still emit a stored block even
495 1.1 paulus * when input comes from standard input. (This can also be done for
496 1.1 paulus * all blocks if lit_bufsize is not greater than 32K.)
497 1.1 paulus * - if compression is not successful for a file smaller than 64K, we can
498 1.1 paulus * even emit a stored file instead of a stored block (saving 5 bytes).
499 1.1 paulus * This is applicable only for zip (not gzip or zlib).
500 1.1 paulus * - creating new Huffman trees less frequently may not provide fast
501 1.1 paulus * adaptation to changes in the input data statistics. (Take for
502 1.1 paulus * example a binary file with poorly compressible code followed by
503 1.1 paulus * a highly compressible string table.) Smaller buffer sizes give
504 1.1 paulus * fast adaptation but have of course the overhead of transmitting
505 1.1 paulus * trees more frequently.
506 1.1 paulus * - I can't count above 4
507 1.1 paulus */
508 1.1 paulus
509 1.1 paulus uInt last_lit; /* running index in l_buf */
510 1.1 paulus
511 1.1 paulus ushf *d_buf;
512 1.1 paulus /* Buffer for distances. To simplify the code, d_buf and l_buf have
513 1.1 paulus * the same number of elements. To use different lengths, an extra flag
514 1.1 paulus * array would be necessary.
515 1.1 paulus */
516 1.1 paulus
517 1.1 paulus ulg opt_len; /* bit length of current block with optimal trees */
518 1.1 paulus ulg static_len; /* bit length of current block with static trees */
519 1.1 paulus uInt matches; /* number of string matches in current block */
520 1.1 paulus int last_eob_len; /* bit length of EOB code for last block */
521 1.1 paulus
522 1.1 paulus #ifdef DEBUG_ZLIB
523 1.17 fvdl ulg compressed_len; /* total bit length of compressed file mod 2^32 */
524 1.17 fvdl ulg bits_sent; /* bit length of compressed data sent mod 2^32 */
525 1.1 paulus #endif
526 1.1 paulus
527 1.1 paulus ush bi_buf;
528 1.1 paulus /* Output buffer. bits are inserted starting at the bottom (least
529 1.1 paulus * significant bits).
530 1.1 paulus */
531 1.1 paulus int bi_valid;
532 1.1 paulus /* Number of valid bits in bi_buf. All bits above the last valid bit
533 1.1 paulus * are always zero.
534 1.1 paulus */
535 1.1 paulus
536 1.1 paulus } FAR deflate_state;
537 1.1 paulus
538 1.1 paulus /* Output a byte on the stream.
539 1.1 paulus * IN assertion: there is enough room in pending_buf.
540 1.1 paulus */
541 1.1 paulus #define put_byte(s, c) {s->pending_buf[s->pending++] = (c);}
542 1.1 paulus
543 1.1 paulus
544 1.1 paulus #define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
545 1.1 paulus /* Minimum amount of lookahead, except at the end of the input file.
546 1.1 paulus * See deflate.c for comments about the MIN_MATCH+1.
547 1.1 paulus */
548 1.1 paulus
549 1.1 paulus #define MAX_DIST(s) ((s)->w_size-MIN_LOOKAHEAD)
550 1.1 paulus /* In order to simplify the code, particularly on 16 bit machines, match
551 1.1 paulus * distances are limited to MAX_DIST instead of WSIZE.
552 1.1 paulus */
553 1.1 paulus
554 1.1 paulus /* in trees.c */
555 1.17 fvdl void _tr_init __P((deflate_state *s));
556 1.17 fvdl int _tr_tally __P((deflate_state *s, unsigned dist, unsigned lc));
557 1.17 fvdl void _tr_flush_block __P((deflate_state *s, charf *buf, ulg stored_len,
558 1.7 christos int eof));
559 1.17 fvdl void _tr_align __P((deflate_state *s));
560 1.17 fvdl void _tr_stored_block __P((deflate_state *s, charf *buf, ulg stored_len,
561 1.1 paulus int eof));
562 1.17 fvdl void _tr_stored_type_only __P((deflate_state *));
563 1.17 fvdl
564 1.17 fvdl #define d_code(dist) \
565 1.17 fvdl ((dist) < 256 ? _dist_code[dist] : _dist_code[256+((dist)>>7)])
566 1.17 fvdl /* Mapping from a distance to a distance code. dist is the distance - 1 and
567 1.17 fvdl * must not have side effects. _dist_code[256] and _dist_code[257] are never
568 1.17 fvdl * used.
569 1.17 fvdl */
570 1.17 fvdl
571 1.17 fvdl #ifndef DEBUG_ZLIB
572 1.17 fvdl /* Inline versions of _tr_tally for speed: */
573 1.17 fvdl
574 1.17 fvdl #if defined(GEN_TREES_H) || !defined(STDC)
575 1.17 fvdl extern uch _length_code[];
576 1.17 fvdl extern uch _dist_code[];
577 1.17 fvdl #else
578 1.17 fvdl extern const uch _length_code[];
579 1.17 fvdl extern const uch _dist_code[];
580 1.17 fvdl #endif
581 1.17 fvdl
582 1.17 fvdl # define _tr_tally_lit(s, c, flush) \
583 1.17 fvdl { uch cc = (c); \
584 1.17 fvdl s->d_buf[s->last_lit] = 0; \
585 1.17 fvdl s->l_buf[s->last_lit++] = cc; \
586 1.17 fvdl s->dyn_ltree[cc].Freq++; \
587 1.17 fvdl flush = (s->last_lit == s->lit_bufsize-1); \
588 1.17 fvdl }
589 1.17 fvdl # define _tr_tally_dist(s, distance, length, flush) \
590 1.17 fvdl { uch len = (length); \
591 1.17 fvdl ush dist = (distance); \
592 1.17 fvdl s->d_buf[s->last_lit] = dist; \
593 1.17 fvdl s->l_buf[s->last_lit++] = len; \
594 1.17 fvdl dist--; \
595 1.17 fvdl s->dyn_ltree[_length_code[len]+LITERALS+1].Freq++; \
596 1.17 fvdl s->dyn_dtree[d_code(dist)].Freq++; \
597 1.17 fvdl flush = (s->last_lit == s->lit_bufsize-1); \
598 1.17 fvdl }
599 1.17 fvdl #else
600 1.17 fvdl # define _tr_tally_lit(s, c, flush) flush = _tr_tally(s, 0, c)
601 1.17 fvdl # define _tr_tally_dist(s, distance, length, flush) \
602 1.20 perry flush = _tr_tally(s, distance, length)
603 1.17 fvdl #endif
604 1.1 paulus
605 1.7 christos #endif
606 1.7 christos /* --- deflate.h */
607 1.1 paulus
608 1.7 christos /* +++ deflate.c */
609 1.17 fvdl
610 1.1 paulus /* deflate.c -- compress data using the deflation algorithm
611 1.17 fvdl * Copyright (C) 1995-2002 Jean-loup Gailly.
612 1.20 perry * For conditions of distribution and use, see copyright notice in zlib.h
613 1.1 paulus */
614 1.1 paulus
615 1.1 paulus /*
616 1.1 paulus * ALGORITHM
617 1.1 paulus *
618 1.1 paulus * The "deflation" process depends on being able to identify portions
619 1.1 paulus * of the input text which are identical to earlier input (within a
620 1.1 paulus * sliding window trailing behind the input currently being processed).
621 1.1 paulus *
622 1.1 paulus * The most straightforward technique turns out to be the fastest for
623 1.1 paulus * most input files: try all possible matches and select the longest.
624 1.1 paulus * The key feature of this algorithm is that insertions into the string
625 1.1 paulus * dictionary are very simple and thus fast, and deletions are avoided
626 1.1 paulus * completely. Insertions are performed at each input character, whereas
627 1.1 paulus * string matches are performed only when the previous match ends. So it
628 1.1 paulus * is preferable to spend more time in matches to allow very fast string
629 1.1 paulus * insertions and avoid deletions. The matching algorithm for small
630 1.1 paulus * strings is inspired from that of Rabin & Karp. A brute force approach
631 1.1 paulus * is used to find longer strings when a small match has been found.
632 1.1 paulus * A similar algorithm is used in comic (by Jan-Mark Wams) and freeze
633 1.1 paulus * (by Leonid Broukhis).
634 1.1 paulus * A previous version of this file used a more sophisticated algorithm
635 1.1 paulus * (by Fiala and Greene) which is guaranteed to run in linear amortized
636 1.1 paulus * time, but has a larger average cost, uses more memory and is patented.
637 1.1 paulus * However the F&G algorithm may be faster for some highly redundant
638 1.1 paulus * files if the parameter max_chain_length (described below) is too large.
639 1.1 paulus *
640 1.1 paulus * ACKNOWLEDGEMENTS
641 1.1 paulus *
642 1.1 paulus * The idea of lazy evaluation of matches is due to Jan-Mark Wams, and
643 1.1 paulus * I found it in 'freeze' written by Leonid Broukhis.
644 1.1 paulus * Thanks to many people for bug reports and testing.
645 1.1 paulus *
646 1.1 paulus * REFERENCES
647 1.1 paulus *
648 1.7 christos * Deutsch, L.P.,"DEFLATE Compressed Data Format Specification".
649 1.7 christos * Available in ftp://ds.internic.net/rfc/rfc1951.txt
650 1.1 paulus *
651 1.1 paulus * A description of the Rabin and Karp algorithm is given in the book
652 1.1 paulus * "Algorithms" by R. Sedgewick, Addison-Wesley, p252.
653 1.1 paulus *
654 1.1 paulus * Fiala,E.R., and Greene,D.H.
655 1.1 paulus * Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595
656 1.1 paulus *
657 1.1 paulus */
658 1.1 paulus
659 1.27 christos /* @(#) $Id: zlib.c,v 1.27 2006/10/12 01:32:30 christos Exp $ */
660 1.7 christos
661 1.7 christos /* #include "deflate.h" */
662 1.1 paulus
663 1.17 fvdl const char deflate_copyright[] =
664 1.17 fvdl " deflate 1.1.4 Copyright 1995-2002 Jean-loup Gailly ";
665 1.1 paulus /*
666 1.1 paulus If you use the zlib library in a product, an acknowledgment is welcome
667 1.1 paulus in the documentation of your product. If for some reason you cannot
668 1.1 paulus include such an acknowledgment, I would appreciate that you keep this
669 1.1 paulus copyright string in the executable of your product.
670 1.1 paulus */
671 1.1 paulus
672 1.7 christos /* ===========================================================================
673 1.7 christos * Function prototypes.
674 1.7 christos */
675 1.7 christos typedef enum {
676 1.7 christos need_more, /* block not completed, need more input or more output */
677 1.7 christos block_done, /* block flush performed */
678 1.7 christos finish_started, /* finish started, need only more output at next deflate */
679 1.7 christos finish_done /* finish done, accept no more input or output */
680 1.7 christos } block_state;
681 1.7 christos
682 1.17 fvdl typedef block_state (*compress_func) __P((deflate_state *s, int flush));
683 1.7 christos /* Compression function. Returns the block state after the call. */
684 1.7 christos
685 1.17 fvdl local void fill_window __P((deflate_state *s));
686 1.17 fvdl local block_state deflate_stored __P((deflate_state *s, int flush));
687 1.17 fvdl local block_state deflate_fast __P((deflate_state *s, int flush));
688 1.17 fvdl local block_state deflate_slow __P((deflate_state *s, int flush));
689 1.17 fvdl local void lm_init __P((deflate_state *s));
690 1.17 fvdl local void putShortMSB __P((deflate_state *s, uInt b));
691 1.17 fvdl local void flush_pending __P((z_streamp strm));
692 1.17 fvdl local int read_buf __P((z_streamp strm, Bytef *buf, unsigned size));
693 1.7 christos #ifdef ASMV
694 1.17 fvdl void match_init __P((void)); /* asm code initialization */
695 1.17 fvdl uInt longest_match __P((deflate_state *s, IPos cur_match));
696 1.7 christos #else
697 1.17 fvdl local uInt longest_match __P((deflate_state *s, IPos cur_match));
698 1.7 christos #endif
699 1.7 christos
700 1.7 christos #ifdef DEBUG_ZLIB
701 1.17 fvdl local void check_match __P((deflate_state *s, IPos start, IPos match,
702 1.7 christos int length));
703 1.7 christos #endif
704 1.7 christos
705 1.7 christos /* ===========================================================================
706 1.7 christos * Local data
707 1.7 christos */
708 1.7 christos
709 1.1 paulus #define NIL 0
710 1.1 paulus /* Tail of hash chains */
711 1.1 paulus
712 1.1 paulus #ifndef TOO_FAR
713 1.1 paulus # define TOO_FAR 4096
714 1.1 paulus #endif
715 1.1 paulus /* Matches of length 3 are discarded if their distance exceeds TOO_FAR */
716 1.1 paulus
717 1.1 paulus #define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
718 1.1 paulus /* Minimum amount of lookahead, except at the end of the input file.
719 1.1 paulus * See deflate.c for comments about the MIN_MATCH+1.
720 1.1 paulus */
721 1.1 paulus
722 1.1 paulus /* Values for max_lazy_match, good_match and max_chain_length, depending on
723 1.1 paulus * the desired pack level (0..9). The values given below have been tuned to
724 1.1 paulus * exclude worst case performance for pathological files. Better values may be
725 1.1 paulus * found for specific files.
726 1.1 paulus */
727 1.1 paulus typedef struct config_s {
728 1.1 paulus ush good_length; /* reduce lazy search above this match length */
729 1.1 paulus ush max_lazy; /* do not perform lazy search above this match length */
730 1.1 paulus ush nice_length; /* quit search above this match length */
731 1.1 paulus ush max_chain;
732 1.7 christos compress_func func;
733 1.1 paulus } config;
734 1.1 paulus
735 1.14 simonb local const config configuration_table[10] = {
736 1.1 paulus /* good lazy nice chain */
737 1.7 christos /* 0 */ {0, 0, 0, 0, deflate_stored}, /* store only */
738 1.7 christos /* 1 */ {4, 4, 8, 4, deflate_fast}, /* maximum speed, no lazy matches */
739 1.7 christos /* 2 */ {4, 5, 16, 8, deflate_fast},
740 1.7 christos /* 3 */ {4, 6, 32, 32, deflate_fast},
741 1.7 christos
742 1.7 christos /* 4 */ {4, 4, 16, 16, deflate_slow}, /* lazy matches */
743 1.7 christos /* 5 */ {8, 16, 32, 32, deflate_slow},
744 1.7 christos /* 6 */ {8, 16, 128, 128, deflate_slow},
745 1.7 christos /* 7 */ {8, 32, 128, 256, deflate_slow},
746 1.7 christos /* 8 */ {32, 128, 258, 1024, deflate_slow},
747 1.7 christos /* 9 */ {32, 258, 258, 4096, deflate_slow}}; /* maximum compression */
748 1.1 paulus
749 1.1 paulus /* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4
750 1.1 paulus * For deflate_fast() (levels <= 3) good is ignored and lazy has a different
751 1.1 paulus * meaning.
752 1.1 paulus */
753 1.1 paulus
754 1.1 paulus #define EQUAL 0
755 1.1 paulus /* result of memcmp for equal strings */
756 1.1 paulus
757 1.7 christos #ifndef NO_DUMMY_DECL
758 1.7 christos struct static_tree_desc_s {int dummy;}; /* for buggy compilers */
759 1.1 paulus #endif
760 1.1 paulus
761 1.1 paulus /* ===========================================================================
762 1.1 paulus * Update a hash value with the given input byte
763 1.1 paulus * IN assertion: all calls to to UPDATE_HASH are made with consecutive
764 1.1 paulus * input characters, so that a running hash key can be computed from the
765 1.1 paulus * previous key instead of complete recalculation each time.
766 1.1 paulus */
767 1.1 paulus #define UPDATE_HASH(s,h,c) (h = (((h)<<s->hash_shift) ^ (c)) & s->hash_mask)
768 1.1 paulus
769 1.1 paulus
770 1.1 paulus /* ===========================================================================
771 1.1 paulus * Insert string str in the dictionary and set match_head to the previous head
772 1.1 paulus * of the hash chain (the most recent string with same hash key). Return
773 1.1 paulus * the previous length of the hash chain.
774 1.17 fvdl * If this file is compiled with -DFASTEST, the compression level is forced
775 1.17 fvdl * to 1, and no hash chains are maintained.
776 1.1 paulus * IN assertion: all calls to to INSERT_STRING are made with consecutive
777 1.1 paulus * input characters and the first MIN_MATCH bytes of str are valid
778 1.1 paulus * (except for the last MIN_MATCH-1 bytes of the input file).
779 1.1 paulus */
780 1.17 fvdl #ifdef FASTEST
781 1.17 fvdl #define INSERT_STRING(s, str, match_head) \
782 1.17 fvdl (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \
783 1.17 fvdl match_head = s->head[s->ins_h], \
784 1.17 fvdl s->head[s->ins_h] = (Pos)(str))
785 1.17 fvdl #else
786 1.1 paulus #define INSERT_STRING(s, str, match_head) \
787 1.1 paulus (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \
788 1.1 paulus s->prev[(str) & s->w_mask] = match_head = s->head[s->ins_h], \
789 1.7 christos s->head[s->ins_h] = (Pos)(str))
790 1.17 fvdl #endif
791 1.1 paulus
792 1.1 paulus /* ===========================================================================
793 1.1 paulus * Initialize the hash table (avoiding 64K overflow for 16 bit systems).
794 1.1 paulus * prev[] will be initialized on the fly.
795 1.1 paulus */
796 1.1 paulus #define CLEAR_HASH(s) \
797 1.1 paulus s->head[s->hash_size-1] = NIL; \
798 1.17 fvdl zmemzero((Bytef *)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head));
799 1.1 paulus
800 1.1 paulus /* ========================================================================= */
801 1.19 kristerw #if 0
802 1.17 fvdl int ZEXPORT deflateInit_(strm, level, version, stream_size)
803 1.7 christos z_streamp strm;
804 1.1 paulus int level;
805 1.7 christos const char *version;
806 1.7 christos int stream_size;
807 1.1 paulus {
808 1.7 christos return deflateInit2_(strm, level, Z_DEFLATED, MAX_WBITS, DEF_MEM_LEVEL,
809 1.7 christos Z_DEFAULT_STRATEGY, version, stream_size);
810 1.1 paulus /* To do: ignore strm->next_in if we use it as window */
811 1.1 paulus }
812 1.19 kristerw #endif
813 1.1 paulus
814 1.1 paulus /* ========================================================================= */
815 1.17 fvdl int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
816 1.21 christos vers, stream_size)
817 1.7 christos z_streamp strm;
818 1.1 paulus int level;
819 1.1 paulus int method;
820 1.1 paulus int windowBits;
821 1.1 paulus int memLevel;
822 1.1 paulus int strategy;
823 1.21 christos const char *vers;
824 1.7 christos int stream_size;
825 1.1 paulus {
826 1.1 paulus deflate_state *s;
827 1.1 paulus int noheader = 0;
828 1.17 fvdl static const char* my_version = ZLIB_VERSION;
829 1.1 paulus
830 1.7 christos ushf *overlay;
831 1.7 christos /* We overlay pending_buf and d_buf+l_buf. This works since the average
832 1.7 christos * output size for (length,distance) codes is <= 24 bits.
833 1.7 christos */
834 1.7 christos
835 1.21 christos if (vers == Z_NULL || vers[0] != my_version[0] ||
836 1.7 christos stream_size != sizeof(z_stream)) {
837 1.7 christos return Z_VERSION_ERROR;
838 1.7 christos }
839 1.1 paulus if (strm == Z_NULL) return Z_STREAM_ERROR;
840 1.1 paulus
841 1.1 paulus strm->msg = Z_NULL;
842 1.7 christos #ifndef NO_ZCFUNCS
843 1.7 christos if (strm->zalloc == Z_NULL) {
844 1.7 christos strm->zalloc = zcalloc;
845 1.7 christos strm->opaque = (voidpf)0;
846 1.7 christos }
847 1.7 christos if (strm->zfree == Z_NULL) strm->zfree = zcfree;
848 1.7 christos #endif
849 1.1 paulus
850 1.1 paulus if (level == Z_DEFAULT_COMPRESSION) level = 6;
851 1.17 fvdl #ifdef FASTEST
852 1.17 fvdl level = 1;
853 1.17 fvdl #endif
854 1.1 paulus
855 1.1 paulus if (windowBits < 0) { /* undocumented feature: suppress zlib header */
856 1.1 paulus noheader = 1;
857 1.1 paulus windowBits = -windowBits;
858 1.1 paulus }
859 1.7 christos if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED ||
860 1.17 fvdl windowBits < 9 || windowBits > 15 || level < 0 || level > 9 ||
861 1.7 christos strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
862 1.1 paulus return Z_STREAM_ERROR;
863 1.1 paulus }
864 1.7 christos s = (deflate_state *) ZALLOC(strm, 1, sizeof(deflate_state));
865 1.1 paulus if (s == Z_NULL) return Z_MEM_ERROR;
866 1.1 paulus strm->state = (struct internal_state FAR *)s;
867 1.1 paulus s->strm = strm;
868 1.1 paulus
869 1.1 paulus s->noheader = noheader;
870 1.1 paulus s->w_bits = windowBits;
871 1.1 paulus s->w_size = 1 << s->w_bits;
872 1.1 paulus s->w_mask = s->w_size - 1;
873 1.1 paulus
874 1.1 paulus s->hash_bits = memLevel + 7;
875 1.1 paulus s->hash_size = 1 << s->hash_bits;
876 1.1 paulus s->hash_mask = s->hash_size - 1;
877 1.1 paulus s->hash_shift = ((s->hash_bits+MIN_MATCH-1)/MIN_MATCH);
878 1.1 paulus
879 1.7 christos s->window = (Bytef *) ZALLOC(strm, s->w_size, 2*sizeof(Byte));
880 1.7 christos s->prev = (Posf *) ZALLOC(strm, s->w_size, sizeof(Pos));
881 1.7 christos s->head = (Posf *) ZALLOC(strm, s->hash_size, sizeof(Pos));
882 1.1 paulus
883 1.1 paulus s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */
884 1.1 paulus
885 1.7 christos overlay = (ushf *) ZALLOC(strm, s->lit_bufsize, sizeof(ush)+2);
886 1.7 christos s->pending_buf = (uchf *) overlay;
887 1.7 christos s->pending_buf_size = (ulg)s->lit_bufsize * (sizeof(ush)+2L);
888 1.1 paulus
889 1.1 paulus if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL ||
890 1.1 paulus s->pending_buf == Z_NULL) {
891 1.21 christos strm->msg = ERR_MSG(Z_MEM_ERROR);
892 1.18 tron s->status = INIT_STATE;
893 1.1 paulus deflateEnd (strm);
894 1.1 paulus return Z_MEM_ERROR;
895 1.1 paulus }
896 1.7 christos s->d_buf = overlay + s->lit_bufsize/sizeof(ush);
897 1.7 christos s->l_buf = s->pending_buf + (1+sizeof(ush))*s->lit_bufsize;
898 1.1 paulus
899 1.1 paulus s->level = level;
900 1.1 paulus s->strategy = strategy;
901 1.1 paulus s->method = (Byte)method;
902 1.1 paulus
903 1.1 paulus return deflateReset(strm);
904 1.1 paulus }
905 1.1 paulus
906 1.1 paulus /* ========================================================================= */
907 1.19 kristerw #if 0
908 1.17 fvdl int ZEXPORT deflateSetDictionary (strm, dictionary, dictLength)
909 1.7 christos z_streamp strm;
910 1.7 christos const Bytef *dictionary;
911 1.7 christos uInt dictLength;
912 1.7 christos {
913 1.7 christos deflate_state *s;
914 1.7 christos uInt length = dictLength;
915 1.7 christos uInt n;
916 1.7 christos IPos hash_head = 0;
917 1.7 christos
918 1.7 christos if (strm == Z_NULL || strm->state == Z_NULL || dictionary == Z_NULL)
919 1.17 fvdl return Z_STREAM_ERROR;
920 1.7 christos
921 1.17 fvdl s = (deflate_state *)strm->state;
922 1.7 christos if (s->status != INIT_STATE) return Z_STREAM_ERROR;
923 1.7 christos
924 1.7 christos strm->adler = adler32(strm->adler, dictionary, dictLength);
925 1.7 christos
926 1.7 christos if (length < MIN_MATCH) return Z_OK;
927 1.7 christos if (length > MAX_DIST(s)) {
928 1.7 christos length = MAX_DIST(s);
929 1.7 christos #ifndef USE_DICT_HEAD
930 1.7 christos dictionary += dictLength - length; /* use the tail of the dictionary */
931 1.7 christos #endif
932 1.7 christos }
933 1.17 fvdl zmemcpy(s->window, dictionary, length);
934 1.7 christos s->strstart = length;
935 1.7 christos s->block_start = (long)length;
936 1.7 christos
937 1.7 christos /* Insert all strings in the hash table (except for the last two bytes).
938 1.7 christos * s->lookahead stays null, so s->ins_h will be recomputed at the next
939 1.7 christos * call of fill_window.
940 1.7 christos */
941 1.7 christos s->ins_h = s->window[0];
942 1.7 christos UPDATE_HASH(s, s->ins_h, s->window[1]);
943 1.7 christos for (n = 0; n <= length - MIN_MATCH; n++) {
944 1.7 christos INSERT_STRING(s, n, hash_head);
945 1.7 christos }
946 1.7 christos if (hash_head) hash_head = 0; /* to make compiler happy */
947 1.7 christos return Z_OK;
948 1.7 christos }
949 1.19 kristerw #endif
950 1.7 christos
951 1.7 christos /* ========================================================================= */
952 1.17 fvdl int ZEXPORT deflateReset (strm)
953 1.7 christos z_streamp strm;
954 1.1 paulus {
955 1.1 paulus deflate_state *s;
956 1.20 perry
957 1.1 paulus if (strm == Z_NULL || strm->state == Z_NULL ||
958 1.7 christos strm->zalloc == Z_NULL || strm->zfree == Z_NULL) return Z_STREAM_ERROR;
959 1.1 paulus
960 1.1 paulus strm->total_in = strm->total_out = 0;
961 1.1 paulus strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */
962 1.1 paulus strm->data_type = Z_UNKNOWN;
963 1.1 paulus
964 1.1 paulus s = (deflate_state *)strm->state;
965 1.1 paulus s->pending = 0;
966 1.1 paulus s->pending_out = s->pending_buf;
967 1.1 paulus
968 1.1 paulus if (s->noheader < 0) {
969 1.1 paulus s->noheader = 0; /* was set to -1 by deflate(..., Z_FINISH); */
970 1.1 paulus }
971 1.1 paulus s->status = s->noheader ? BUSY_STATE : INIT_STATE;
972 1.7 christos strm->adler = 1;
973 1.7 christos s->last_flush = Z_NO_FLUSH;
974 1.1 paulus
975 1.7 christos _tr_init(s);
976 1.1 paulus lm_init(s);
977 1.1 paulus
978 1.1 paulus return Z_OK;
979 1.1 paulus }
980 1.1 paulus
981 1.7 christos /* ========================================================================= */
982 1.19 kristerw #if 0
983 1.17 fvdl int ZEXPORT deflateParams(strm, level, strategy)
984 1.7 christos z_streamp strm;
985 1.7 christos int level;
986 1.7 christos int strategy;
987 1.7 christos {
988 1.7 christos deflate_state *s;
989 1.7 christos compress_func func;
990 1.7 christos int err = Z_OK;
991 1.7 christos
992 1.7 christos if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
993 1.17 fvdl s = (deflate_state *)strm->state;
994 1.7 christos
995 1.7 christos if (level == Z_DEFAULT_COMPRESSION) {
996 1.7 christos level = 6;
997 1.7 christos }
998 1.7 christos if (level < 0 || level > 9 || strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
999 1.7 christos return Z_STREAM_ERROR;
1000 1.7 christos }
1001 1.7 christos func = configuration_table[s->level].func;
1002 1.7 christos
1003 1.7 christos if (func != configuration_table[level].func && strm->total_in != 0) {
1004 1.7 christos /* Flush the last buffer: */
1005 1.7 christos err = deflate(strm, Z_PARTIAL_FLUSH);
1006 1.7 christos }
1007 1.7 christos if (s->level != level) {
1008 1.7 christos s->level = level;
1009 1.7 christos s->max_lazy_match = configuration_table[level].max_lazy;
1010 1.7 christos s->good_match = configuration_table[level].good_length;
1011 1.7 christos s->nice_match = configuration_table[level].nice_length;
1012 1.7 christos s->max_chain_length = configuration_table[level].max_chain;
1013 1.7 christos }
1014 1.7 christos s->strategy = strategy;
1015 1.7 christos return err;
1016 1.7 christos }
1017 1.19 kristerw #endif
1018 1.7 christos
1019 1.1 paulus /* =========================================================================
1020 1.1 paulus * Put a short in the pending buffer. The 16-bit value is put in MSB order.
1021 1.1 paulus * IN assertion: the stream state is correct and there is enough room in
1022 1.1 paulus * pending_buf.
1023 1.1 paulus */
1024 1.1 paulus local void putShortMSB (s, b)
1025 1.1 paulus deflate_state *s;
1026 1.1 paulus uInt b;
1027 1.1 paulus {
1028 1.1 paulus put_byte(s, (Byte)(b >> 8));
1029 1.1 paulus put_byte(s, (Byte)(b & 0xff));
1030 1.20 perry }
1031 1.1 paulus
1032 1.1 paulus /* =========================================================================
1033 1.7 christos * Flush as much pending output as possible. All deflate() output goes
1034 1.7 christos * through this function so some applications may wish to modify it
1035 1.7 christos * to avoid allocating a large strm->next_out buffer and copying into it.
1036 1.7 christos * (See also read_buf()).
1037 1.1 paulus */
1038 1.1 paulus local void flush_pending(strm)
1039 1.7 christos z_streamp strm;
1040 1.1 paulus {
1041 1.7 christos deflate_state *s = (deflate_state *) strm->state;
1042 1.7 christos unsigned len = s->pending;
1043 1.1 paulus
1044 1.1 paulus if (len > strm->avail_out) len = strm->avail_out;
1045 1.1 paulus if (len == 0) return;
1046 1.1 paulus
1047 1.7 christos if (strm->next_out != Z_NULL) {
1048 1.17 fvdl zmemcpy(strm->next_out, s->pending_out, len);
1049 1.17 fvdl strm->next_out += len;
1050 1.1 paulus }
1051 1.17 fvdl s->pending_out += len;
1052 1.1 paulus strm->total_out += len;
1053 1.7 christos strm->avail_out -= len;
1054 1.7 christos s->pending -= len;
1055 1.7 christos if (s->pending == 0) {
1056 1.7 christos s->pending_out = s->pending_buf;
1057 1.1 paulus }
1058 1.1 paulus }
1059 1.1 paulus
1060 1.1 paulus /* ========================================================================= */
1061 1.17 fvdl int ZEXPORT deflate (strm, flush)
1062 1.7 christos z_streamp strm;
1063 1.1 paulus int flush;
1064 1.1 paulus {
1065 1.7 christos int old_flush; /* value of flush param for previous deflate call */
1066 1.7 christos deflate_state *s;
1067 1.7 christos
1068 1.7 christos if (strm == Z_NULL || strm->state == Z_NULL ||
1069 1.7 christos flush > Z_FINISH || flush < 0) {
1070 1.7 christos return Z_STREAM_ERROR;
1071 1.7 christos }
1072 1.17 fvdl s = (deflate_state *)strm->state;
1073 1.1 paulus
1074 1.7 christos if ((strm->next_in == Z_NULL && strm->avail_in != 0) ||
1075 1.7 christos (s->status == FINISH_STATE && flush != Z_FINISH)) {
1076 1.1 paulus ERR_RETURN(strm, Z_STREAM_ERROR);
1077 1.1 paulus }
1078 1.1 paulus if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR);
1079 1.1 paulus
1080 1.7 christos s->strm = strm; /* just in case */
1081 1.7 christos old_flush = s->last_flush;
1082 1.7 christos s->last_flush = flush;
1083 1.1 paulus
1084 1.1 paulus /* Write the zlib header */
1085 1.7 christos if (s->status == INIT_STATE) {
1086 1.1 paulus
1087 1.7 christos uInt header = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8;
1088 1.7 christos uInt level_flags = (s->level-1) >> 1;
1089 1.1 paulus
1090 1.1 paulus if (level_flags > 3) level_flags = 3;
1091 1.1 paulus header |= (level_flags << 6);
1092 1.7 christos if (s->strstart != 0) header |= PRESET_DICT;
1093 1.1 paulus header += 31 - (header % 31);
1094 1.1 paulus
1095 1.7 christos s->status = BUSY_STATE;
1096 1.7 christos putShortMSB(s, header);
1097 1.7 christos
1098 1.7 christos /* Save the adler32 of the preset dictionary: */
1099 1.7 christos if (s->strstart != 0) {
1100 1.7 christos putShortMSB(s, (uInt)(strm->adler >> 16));
1101 1.7 christos putShortMSB(s, (uInt)(strm->adler & 0xffff));
1102 1.7 christos }
1103 1.7 christos strm->adler = 1L;
1104 1.1 paulus }
1105 1.1 paulus
1106 1.1 paulus /* Flush as much pending output as possible */
1107 1.7 christos if (s->pending != 0) {
1108 1.1 paulus flush_pending(strm);
1109 1.7 christos if (strm->avail_out == 0) {
1110 1.7 christos /* Since avail_out is 0, deflate will be called again with
1111 1.7 christos * more output space, but possibly with both pending and
1112 1.7 christos * avail_in equal to zero. There won't be anything to do,
1113 1.7 christos * but this is not an error situation so make sure we
1114 1.7 christos * return OK instead of BUF_ERROR at next call of deflate:
1115 1.7 christos */
1116 1.7 christos s->last_flush = -1;
1117 1.7 christos return Z_OK;
1118 1.7 christos }
1119 1.1 paulus
1120 1.7 christos /* Make sure there is something to do and avoid duplicate consecutive
1121 1.7 christos * flushes. For repeated and useless calls with Z_FINISH, we keep
1122 1.7 christos * returning Z_STREAM_END instead of Z_BUFF_ERROR.
1123 1.1 paulus */
1124 1.7 christos } else if (strm->avail_in == 0 && flush <= old_flush &&
1125 1.7 christos flush != Z_FINISH) {
1126 1.7 christos ERR_RETURN(strm, Z_BUF_ERROR);
1127 1.1 paulus }
1128 1.1 paulus
1129 1.1 paulus /* User must not provide more input after the first FINISH: */
1130 1.7 christos if (s->status == FINISH_STATE && strm->avail_in != 0) {
1131 1.1 paulus ERR_RETURN(strm, Z_BUF_ERROR);
1132 1.1 paulus }
1133 1.1 paulus
1134 1.1 paulus /* Start a new block or continue the current one.
1135 1.1 paulus */
1136 1.7 christos if (strm->avail_in != 0 || s->lookahead != 0 ||
1137 1.7 christos (flush != Z_NO_FLUSH && s->status != FINISH_STATE)) {
1138 1.7 christos block_state bstate;
1139 1.1 paulus
1140 1.7 christos bstate = (*(configuration_table[s->level].func))(s, flush);
1141 1.7 christos
1142 1.7 christos if (bstate == finish_started || bstate == finish_done) {
1143 1.7 christos s->status = FINISH_STATE;
1144 1.1 paulus }
1145 1.7 christos if (bstate == need_more || bstate == finish_started) {
1146 1.7 christos if (strm->avail_out == 0) {
1147 1.7 christos s->last_flush = -1; /* avoid BUF_ERROR next call, see above */
1148 1.7 christos }
1149 1.1 paulus return Z_OK;
1150 1.7 christos /* If flush != Z_NO_FLUSH && avail_out == 0, the next call
1151 1.7 christos * of deflate should use the same flush parameter to make sure
1152 1.7 christos * that the flush is complete. So we don't have to output an
1153 1.7 christos * empty block here, this will be done at next call. This also
1154 1.7 christos * ensures that for a very small output buffer, we emit at most
1155 1.7 christos * one empty block.
1156 1.1 paulus */
1157 1.7 christos }
1158 1.7 christos if (bstate == block_done) {
1159 1.7 christos if (flush == Z_PARTIAL_FLUSH) {
1160 1.7 christos _tr_align(s);
1161 1.7 christos } else if (flush == Z_PACKET_FLUSH) {
1162 1.7 christos /* Output just the 3-bit `stored' block type value,
1163 1.7 christos but not a zero length. */
1164 1.7 christos _tr_stored_type_only(s);
1165 1.7 christos } else { /* FULL_FLUSH or SYNC_FLUSH */
1166 1.7 christos _tr_stored_block(s, (char*)0, 0L, 0);
1167 1.7 christos /* For a full flush, this empty block will be recognized
1168 1.7 christos * as a special marker by inflate_sync().
1169 1.7 christos */
1170 1.7 christos if (flush == Z_FULL_FLUSH) {
1171 1.7 christos CLEAR_HASH(s); /* forget history */
1172 1.7 christos }
1173 1.7 christos }
1174 1.7 christos flush_pending(strm);
1175 1.7 christos if (strm->avail_out == 0) {
1176 1.7 christos s->last_flush = -1; /* avoid BUF_ERROR at next call, see above */
1177 1.7 christos return Z_OK;
1178 1.1 paulus }
1179 1.7 christos }
1180 1.1 paulus }
1181 1.1 paulus Assert(strm->avail_out > 0, "bug2");
1182 1.1 paulus
1183 1.1 paulus if (flush != Z_FINISH) return Z_OK;
1184 1.7 christos if (s->noheader) return Z_STREAM_END;
1185 1.1 paulus
1186 1.1 paulus /* Write the zlib trailer (adler32) */
1187 1.7 christos putShortMSB(s, (uInt)(strm->adler >> 16));
1188 1.7 christos putShortMSB(s, (uInt)(strm->adler & 0xffff));
1189 1.1 paulus flush_pending(strm);
1190 1.1 paulus /* If avail_out is zero, the application will call deflate again
1191 1.1 paulus * to flush the rest.
1192 1.1 paulus */
1193 1.7 christos s->noheader = -1; /* write the trailer only once! */
1194 1.7 christos return s->pending != 0 ? Z_OK : Z_STREAM_END;
1195 1.1 paulus }
1196 1.1 paulus
1197 1.1 paulus /* ========================================================================= */
1198 1.17 fvdl int ZEXPORT deflateEnd (strm)
1199 1.7 christos z_streamp strm;
1200 1.1 paulus {
1201 1.7 christos int status;
1202 1.7 christos deflate_state *s;
1203 1.1 paulus
1204 1.7 christos if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
1205 1.7 christos s = (deflate_state *) strm->state;
1206 1.1 paulus
1207 1.7 christos status = s->status;
1208 1.7 christos if (status != INIT_STATE && status != BUSY_STATE &&
1209 1.7 christos status != FINISH_STATE) {
1210 1.7 christos return Z_STREAM_ERROR;
1211 1.7 christos }
1212 1.1 paulus
1213 1.7 christos /* Deallocate in reverse order of allocations: */
1214 1.7 christos TRY_FREE(strm, s->pending_buf);
1215 1.7 christos TRY_FREE(strm, s->head);
1216 1.7 christos TRY_FREE(strm, s->prev);
1217 1.7 christos TRY_FREE(strm, s->window);
1218 1.7 christos
1219 1.7 christos ZFREE(strm, s);
1220 1.1 paulus strm->state = Z_NULL;
1221 1.1 paulus
1222 1.7 christos return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK;
1223 1.7 christos }
1224 1.7 christos
1225 1.7 christos /* =========================================================================
1226 1.7 christos * Copy the source state to the destination state.
1227 1.17 fvdl * To simplify the source, this is not supported for 16-bit MSDOS (which
1228 1.17 fvdl * doesn't have enough memory anyway to duplicate compression states).
1229 1.7 christos */
1230 1.19 kristerw #if 0
1231 1.17 fvdl int ZEXPORT deflateCopy (dest, source)
1232 1.7 christos z_streamp dest;
1233 1.7 christos z_streamp source;
1234 1.7 christos {
1235 1.17 fvdl #ifdef MAXSEG_64K
1236 1.17 fvdl return Z_STREAM_ERROR;
1237 1.17 fvdl #else
1238 1.7 christos deflate_state *ds;
1239 1.7 christos deflate_state *ss;
1240 1.7 christos ushf *overlay;
1241 1.7 christos
1242 1.17 fvdl
1243 1.17 fvdl if (source == Z_NULL || dest == Z_NULL || source->state == Z_NULL) {
1244 1.7 christos return Z_STREAM_ERROR;
1245 1.17 fvdl }
1246 1.7 christos
1247 1.17 fvdl ss = (deflate_state *)source->state;
1248 1.17 fvdl
1249 1.17 fvdl *dest = *source;
1250 1.7 christos
1251 1.7 christos ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state));
1252 1.7 christos if (ds == Z_NULL) return Z_MEM_ERROR;
1253 1.17 fvdl dest->state = (void *) ds;
1254 1.17 fvdl *ds = *ss;
1255 1.7 christos ds->strm = dest;
1256 1.7 christos
1257 1.7 christos ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte));
1258 1.7 christos ds->prev = (Posf *) ZALLOC(dest, ds->w_size, sizeof(Pos));
1259 1.7 christos ds->head = (Posf *) ZALLOC(dest, ds->hash_size, sizeof(Pos));
1260 1.7 christos overlay = (ushf *) ZALLOC(dest, ds->lit_bufsize, sizeof(ush)+2);
1261 1.7 christos ds->pending_buf = (uchf *) overlay;
1262 1.7 christos
1263 1.7 christos if (ds->window == Z_NULL || ds->prev == Z_NULL || ds->head == Z_NULL ||
1264 1.7 christos ds->pending_buf == Z_NULL) {
1265 1.18 tron ds->status = INIT_STATE;
1266 1.7 christos deflateEnd (dest);
1267 1.7 christos return Z_MEM_ERROR;
1268 1.7 christos }
1269 1.17 fvdl /* following zmemcpy do not work for 16-bit MSDOS */
1270 1.7 christos zmemcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte));
1271 1.7 christos zmemcpy(ds->prev, ss->prev, ds->w_size * sizeof(Pos));
1272 1.7 christos zmemcpy(ds->head, ss->head, ds->hash_size * sizeof(Pos));
1273 1.7 christos zmemcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size);
1274 1.7 christos
1275 1.7 christos ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf);
1276 1.7 christos ds->d_buf = overlay + ds->lit_bufsize/sizeof(ush);
1277 1.7 christos ds->l_buf = ds->pending_buf + (1+sizeof(ush))*ds->lit_bufsize;
1278 1.7 christos
1279 1.7 christos ds->l_desc.dyn_tree = ds->dyn_ltree;
1280 1.7 christos ds->d_desc.dyn_tree = ds->dyn_dtree;
1281 1.7 christos ds->bl_desc.dyn_tree = ds->bl_tree;
1282 1.7 christos
1283 1.1 paulus return Z_OK;
1284 1.17 fvdl #endif
1285 1.1 paulus }
1286 1.19 kristerw #endif
1287 1.1 paulus
1288 1.1 paulus /* ===========================================================================
1289 1.7 christos * Return the number of bytes of output which are immediately available
1290 1.7 christos * for output from the decompressor.
1291 1.7 christos */
1292 1.19 kristerw #if 0
1293 1.7 christos int deflateOutputPending (strm)
1294 1.7 christos z_streamp strm;
1295 1.7 christos {
1296 1.7 christos if (strm == Z_NULL || strm->state == Z_NULL) return 0;
1297 1.20 perry
1298 1.7 christos return ((deflate_state *)(strm->state))->pending;
1299 1.7 christos }
1300 1.19 kristerw #endif
1301 1.7 christos
1302 1.7 christos /* ===========================================================================
1303 1.1 paulus * Read a new buffer from the current input stream, update the adler32
1304 1.7 christos * and total number of bytes read. All deflate() input goes through
1305 1.7 christos * this function so some applications may wish to modify it to avoid
1306 1.7 christos * allocating a large strm->next_in buffer and copying from it.
1307 1.7 christos * (See also flush_pending()).
1308 1.1 paulus */
1309 1.1 paulus local int read_buf(strm, buf, size)
1310 1.7 christos z_streamp strm;
1311 1.17 fvdl Bytef *buf;
1312 1.1 paulus unsigned size;
1313 1.1 paulus {
1314 1.1 paulus unsigned len = strm->avail_in;
1315 1.1 paulus
1316 1.1 paulus if (len > size) len = size;
1317 1.1 paulus if (len == 0) return 0;
1318 1.1 paulus
1319 1.1 paulus strm->avail_in -= len;
1320 1.1 paulus
1321 1.7 christos if (!((deflate_state *)(strm->state))->noheader) {
1322 1.7 christos strm->adler = adler32(strm->adler, strm->next_in, len);
1323 1.1 paulus }
1324 1.1 paulus zmemcpy(buf, strm->next_in, len);
1325 1.1 paulus strm->next_in += len;
1326 1.1 paulus strm->total_in += len;
1327 1.1 paulus
1328 1.1 paulus return (int)len;
1329 1.1 paulus }
1330 1.1 paulus
1331 1.1 paulus /* ===========================================================================
1332 1.1 paulus * Initialize the "longest match" routines for a new zlib stream
1333 1.1 paulus */
1334 1.1 paulus local void lm_init (s)
1335 1.1 paulus deflate_state *s;
1336 1.1 paulus {
1337 1.1 paulus s->window_size = (ulg)2L*s->w_size;
1338 1.1 paulus
1339 1.1 paulus CLEAR_HASH(s);
1340 1.1 paulus
1341 1.1 paulus /* Set the default configuration parameters:
1342 1.1 paulus */
1343 1.1 paulus s->max_lazy_match = configuration_table[s->level].max_lazy;
1344 1.1 paulus s->good_match = configuration_table[s->level].good_length;
1345 1.1 paulus s->nice_match = configuration_table[s->level].nice_length;
1346 1.1 paulus s->max_chain_length = configuration_table[s->level].max_chain;
1347 1.1 paulus
1348 1.1 paulus s->strstart = 0;
1349 1.1 paulus s->block_start = 0L;
1350 1.1 paulus s->lookahead = 0;
1351 1.7 christos s->match_length = s->prev_length = MIN_MATCH-1;
1352 1.1 paulus s->match_available = 0;
1353 1.1 paulus s->ins_h = 0;
1354 1.1 paulus #ifdef ASMV
1355 1.1 paulus match_init(); /* initialize the asm code */
1356 1.1 paulus #endif
1357 1.1 paulus }
1358 1.1 paulus
1359 1.1 paulus /* ===========================================================================
1360 1.1 paulus * Set match_start to the longest match starting at the given string and
1361 1.1 paulus * return its length. Matches shorter or equal to prev_length are discarded,
1362 1.1 paulus * in which case the result is equal to prev_length and match_start is
1363 1.1 paulus * garbage.
1364 1.1 paulus * IN assertions: cur_match is the head of the hash chain for the current
1365 1.1 paulus * string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1
1366 1.7 christos * OUT assertion: the match length is not greater than s->lookahead.
1367 1.1 paulus */
1368 1.1 paulus #ifndef ASMV
1369 1.1 paulus /* For 80x86 and 680x0, an optimized version will be provided in match.asm or
1370 1.1 paulus * match.S. The code will be functionally equivalent.
1371 1.1 paulus */
1372 1.17 fvdl #ifndef FASTEST
1373 1.7 christos local uInt longest_match(s, cur_match)
1374 1.1 paulus deflate_state *s;
1375 1.1 paulus IPos cur_match; /* current match */
1376 1.1 paulus {
1377 1.1 paulus unsigned chain_length = s->max_chain_length;/* max hash chain length */
1378 1.17 fvdl Bytef *scan = s->window + s->strstart; /* current string */
1379 1.17 fvdl Bytef *match; /* matched string */
1380 1.17 fvdl int len; /* length of current match */
1381 1.1 paulus int best_len = s->prev_length; /* best match length so far */
1382 1.7 christos int nice_match = s->nice_match; /* stop if match long enough */
1383 1.1 paulus IPos limit = s->strstart > (IPos)MAX_DIST(s) ?
1384 1.1 paulus s->strstart - (IPos)MAX_DIST(s) : NIL;
1385 1.1 paulus /* Stop when cur_match becomes <= limit. To simplify the code,
1386 1.1 paulus * we prevent matches with the string of window index 0.
1387 1.1 paulus */
1388 1.1 paulus Posf *prev = s->prev;
1389 1.1 paulus uInt wmask = s->w_mask;
1390 1.1 paulus
1391 1.1 paulus #ifdef UNALIGNED_OK
1392 1.1 paulus /* Compare two bytes at a time. Note: this is not always beneficial.
1393 1.1 paulus * Try with and without -DUNALIGNED_OK to check.
1394 1.1 paulus */
1395 1.10 augustss Bytef *strend = s->window + s->strstart + MAX_MATCH - 1;
1396 1.10 augustss ush scan_start = *(ushf*)scan;
1397 1.10 augustss ush scan_end = *(ushf*)(scan+best_len-1);
1398 1.1 paulus #else
1399 1.10 augustss Bytef *strend = s->window + s->strstart + MAX_MATCH;
1400 1.10 augustss Byte scan_end1 = scan[best_len-1];
1401 1.10 augustss Byte scan_end = scan[best_len];
1402 1.1 paulus #endif
1403 1.1 paulus
1404 1.1 paulus /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
1405 1.1 paulus * It is easy to get rid of this optimization if necessary.
1406 1.1 paulus */
1407 1.1 paulus Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");
1408 1.1 paulus
1409 1.1 paulus /* Do not waste too much time if we already have a good match: */
1410 1.1 paulus if (s->prev_length >= s->good_match) {
1411 1.1 paulus chain_length >>= 2;
1412 1.1 paulus }
1413 1.7 christos /* Do not look for matches beyond the end of the input. This is necessary
1414 1.7 christos * to make deflate deterministic.
1415 1.7 christos */
1416 1.7 christos if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;
1417 1.7 christos
1418 1.1 paulus Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
1419 1.1 paulus
1420 1.1 paulus do {
1421 1.1 paulus Assert(cur_match < s->strstart, "no future");
1422 1.1 paulus match = s->window + cur_match;
1423 1.1 paulus
1424 1.1 paulus /* Skip to next match if the match length cannot increase
1425 1.1 paulus * or if the match length is less than 2:
1426 1.1 paulus */
1427 1.1 paulus #if (defined(UNALIGNED_OK) && MAX_MATCH == 258)
1428 1.1 paulus /* This code assumes sizeof(unsigned short) == 2. Do not use
1429 1.1 paulus * UNALIGNED_OK if your compiler uses a different size.
1430 1.1 paulus */
1431 1.1 paulus if (*(ushf*)(match+best_len-1) != scan_end ||
1432 1.1 paulus *(ushf*)match != scan_start) continue;
1433 1.1 paulus
1434 1.1 paulus /* It is not necessary to compare scan[2] and match[2] since they are
1435 1.1 paulus * always equal when the other bytes match, given that the hash keys
1436 1.1 paulus * are equal and that HASH_BITS >= 8. Compare 2 bytes at a time at
1437 1.1 paulus * strstart+3, +5, ... up to strstart+257. We check for insufficient
1438 1.1 paulus * lookahead only every 4th comparison; the 128th check will be made
1439 1.1 paulus * at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is
1440 1.1 paulus * necessary to put more guard bytes at the end of the window, or
1441 1.1 paulus * to check more often for insufficient lookahead.
1442 1.1 paulus */
1443 1.1 paulus Assert(scan[2] == match[2], "scan[2]?");
1444 1.1 paulus scan++, match++;
1445 1.1 paulus do {
1446 1.1 paulus } while (*(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1447 1.1 paulus *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1448 1.1 paulus *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1449 1.1 paulus *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1450 1.1 paulus scan < strend);
1451 1.1 paulus /* The funny "do {}" generates better code on most compilers */
1452 1.1 paulus
1453 1.1 paulus /* Here, scan <= window+strstart+257 */
1454 1.1 paulus Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1455 1.1 paulus if (*scan == *match) scan++;
1456 1.1 paulus
1457 1.1 paulus len = (MAX_MATCH - 1) - (int)(strend-scan);
1458 1.1 paulus scan = strend - (MAX_MATCH-1);
1459 1.1 paulus
1460 1.1 paulus #else /* UNALIGNED_OK */
1461 1.1 paulus
1462 1.1 paulus if (match[best_len] != scan_end ||
1463 1.1 paulus match[best_len-1] != scan_end1 ||
1464 1.1 paulus *match != *scan ||
1465 1.1 paulus *++match != scan[1]) continue;
1466 1.1 paulus
1467 1.1 paulus /* The check at best_len-1 can be removed because it will be made
1468 1.1 paulus * again later. (This heuristic is not always a win.)
1469 1.1 paulus * It is not necessary to compare scan[2] and match[2] since they
1470 1.1 paulus * are always equal when the other bytes match, given that
1471 1.1 paulus * the hash keys are equal and that HASH_BITS >= 8.
1472 1.1 paulus */
1473 1.1 paulus scan += 2, match++;
1474 1.1 paulus Assert(*scan == *match, "match[2]?");
1475 1.1 paulus
1476 1.1 paulus /* We check for insufficient lookahead only every 8th comparison;
1477 1.1 paulus * the 256th check will be made at strstart+258.
1478 1.1 paulus */
1479 1.1 paulus do {
1480 1.1 paulus } while (*++scan == *++match && *++scan == *++match &&
1481 1.1 paulus *++scan == *++match && *++scan == *++match &&
1482 1.1 paulus *++scan == *++match && *++scan == *++match &&
1483 1.1 paulus *++scan == *++match && *++scan == *++match &&
1484 1.1 paulus scan < strend);
1485 1.1 paulus
1486 1.1 paulus Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1487 1.1 paulus
1488 1.1 paulus len = MAX_MATCH - (int)(strend - scan);
1489 1.1 paulus scan = strend - MAX_MATCH;
1490 1.1 paulus
1491 1.1 paulus #endif /* UNALIGNED_OK */
1492 1.1 paulus
1493 1.1 paulus if (len > best_len) {
1494 1.1 paulus s->match_start = cur_match;
1495 1.1 paulus best_len = len;
1496 1.7 christos if (len >= nice_match) break;
1497 1.1 paulus #ifdef UNALIGNED_OK
1498 1.1 paulus scan_end = *(ushf*)(scan+best_len-1);
1499 1.1 paulus #else
1500 1.1 paulus scan_end1 = scan[best_len-1];
1501 1.1 paulus scan_end = scan[best_len];
1502 1.1 paulus #endif
1503 1.1 paulus }
1504 1.1 paulus } while ((cur_match = prev[cur_match & wmask]) > limit
1505 1.1 paulus && --chain_length != 0);
1506 1.1 paulus
1507 1.17 fvdl if ((uInt)best_len <= s->lookahead) return (uInt)best_len;
1508 1.7 christos return s->lookahead;
1509 1.1 paulus }
1510 1.17 fvdl
1511 1.17 fvdl #else /* FASTEST */
1512 1.17 fvdl /* ---------------------------------------------------------------------------
1513 1.17 fvdl * Optimized version for level == 1 only
1514 1.17 fvdl */
1515 1.17 fvdl local uInt longest_match(s, cur_match)
1516 1.17 fvdl deflate_state *s;
1517 1.17 fvdl IPos cur_match; /* current match */
1518 1.17 fvdl {
1519 1.17 fvdl register Bytef *scan = s->window + s->strstart; /* current string */
1520 1.17 fvdl register Bytef *match; /* matched string */
1521 1.17 fvdl register int len; /* length of current match */
1522 1.17 fvdl register Bytef *strend = s->window + s->strstart + MAX_MATCH;
1523 1.17 fvdl
1524 1.17 fvdl /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
1525 1.17 fvdl * It is easy to get rid of this optimization if necessary.
1526 1.17 fvdl */
1527 1.17 fvdl Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");
1528 1.17 fvdl
1529 1.17 fvdl Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
1530 1.17 fvdl
1531 1.17 fvdl Assert(cur_match < s->strstart, "no future");
1532 1.17 fvdl
1533 1.17 fvdl match = s->window + cur_match;
1534 1.17 fvdl
1535 1.17 fvdl /* Return failure if the match length is less than 2:
1536 1.17 fvdl */
1537 1.17 fvdl if (match[0] != scan[0] || match[1] != scan[1]) return MIN_MATCH-1;
1538 1.17 fvdl
1539 1.17 fvdl /* The check at best_len-1 can be removed because it will be made
1540 1.17 fvdl * again later. (This heuristic is not always a win.)
1541 1.17 fvdl * It is not necessary to compare scan[2] and match[2] since they
1542 1.17 fvdl * are always equal when the other bytes match, given that
1543 1.17 fvdl * the hash keys are equal and that HASH_BITS >= 8.
1544 1.17 fvdl */
1545 1.17 fvdl scan += 2, match += 2;
1546 1.17 fvdl Assert(*scan == *match, "match[2]?");
1547 1.17 fvdl
1548 1.17 fvdl /* We check for insufficient lookahead only every 8th comparison;
1549 1.17 fvdl * the 256th check will be made at strstart+258.
1550 1.17 fvdl */
1551 1.17 fvdl do {
1552 1.17 fvdl } while (*++scan == *++match && *++scan == *++match &&
1553 1.17 fvdl *++scan == *++match && *++scan == *++match &&
1554 1.17 fvdl *++scan == *++match && *++scan == *++match &&
1555 1.17 fvdl *++scan == *++match && *++scan == *++match &&
1556 1.17 fvdl scan < strend);
1557 1.17 fvdl
1558 1.17 fvdl Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1559 1.17 fvdl
1560 1.17 fvdl len = MAX_MATCH - (int)(strend - scan);
1561 1.17 fvdl
1562 1.17 fvdl if (len < MIN_MATCH) return MIN_MATCH - 1;
1563 1.17 fvdl
1564 1.17 fvdl s->match_start = cur_match;
1565 1.17 fvdl return len <= s->lookahead ? len : s->lookahead;
1566 1.17 fvdl }
1567 1.17 fvdl #endif /* FASTEST */
1568 1.1 paulus #endif /* ASMV */
1569 1.1 paulus
1570 1.1 paulus #ifdef DEBUG_ZLIB
1571 1.1 paulus /* ===========================================================================
1572 1.1 paulus * Check that the match at match_start is indeed a match.
1573 1.1 paulus */
1574 1.1 paulus local void check_match(s, start, match, length)
1575 1.1 paulus deflate_state *s;
1576 1.1 paulus IPos start, match;
1577 1.1 paulus int length;
1578 1.1 paulus {
1579 1.1 paulus /* check that the match is indeed a match */
1580 1.17 fvdl if (zmemcmp(s->window + match,
1581 1.17 fvdl s->window + start, length) != EQUAL) {
1582 1.7 christos fprintf(stderr, " start %u, match %u, length %d\n",
1583 1.7 christos start, match, length);
1584 1.7 christos do {
1585 1.7 christos fprintf(stderr, "%c%c", s->window[match++], s->window[start++]);
1586 1.7 christos } while (--length != 0);
1587 1.1 paulus z_error("invalid match");
1588 1.1 paulus }
1589 1.7 christos if (z_verbose > 1) {
1590 1.1 paulus fprintf(stderr,"\\[%d,%d]", start-match, length);
1591 1.1 paulus do { putc(s->window[start++], stderr); } while (--length != 0);
1592 1.1 paulus }
1593 1.1 paulus }
1594 1.1 paulus #else
1595 1.1 paulus # define check_match(s, start, match, length)
1596 1.1 paulus #endif
1597 1.1 paulus
1598 1.1 paulus /* ===========================================================================
1599 1.1 paulus * Fill the window when the lookahead becomes insufficient.
1600 1.1 paulus * Updates strstart and lookahead.
1601 1.1 paulus *
1602 1.1 paulus * IN assertion: lookahead < MIN_LOOKAHEAD
1603 1.1 paulus * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD
1604 1.1 paulus * At least one byte has been read, or avail_in == 0; reads are
1605 1.1 paulus * performed for at least two bytes (required for the zip translate_eol
1606 1.1 paulus * option -- not supported here).
1607 1.1 paulus */
1608 1.1 paulus local void fill_window(s)
1609 1.1 paulus deflate_state *s;
1610 1.1 paulus {
1611 1.10 augustss unsigned n, m;
1612 1.10 augustss Posf *p;
1613 1.1 paulus unsigned more; /* Amount of free space at the end of the window. */
1614 1.1 paulus uInt wsize = s->w_size;
1615 1.1 paulus
1616 1.1 paulus do {
1617 1.1 paulus more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart);
1618 1.1 paulus
1619 1.1 paulus /* Deal with !@#$% 64K limit: */
1620 1.1 paulus if (more == 0 && s->strstart == 0 && s->lookahead == 0) {
1621 1.1 paulus more = wsize;
1622 1.7 christos
1623 1.1 paulus } else if (more == (unsigned)(-1)) {
1624 1.1 paulus /* Very unlikely, but possible on 16 bit machine if strstart == 0
1625 1.1 paulus * and lookahead == 1 (input done one byte at time)
1626 1.1 paulus */
1627 1.1 paulus more--;
1628 1.1 paulus
1629 1.1 paulus /* If the window is almost full and there is insufficient lookahead,
1630 1.1 paulus * move the upper half to the lower one to make room in the upper half.
1631 1.1 paulus */
1632 1.1 paulus } else if (s->strstart >= wsize+MAX_DIST(s)) {
1633 1.1 paulus
1634 1.17 fvdl zmemcpy(s->window, s->window+wsize, (unsigned)wsize);
1635 1.1 paulus s->match_start -= wsize;
1636 1.1 paulus s->strstart -= wsize; /* we now have strstart >= MAX_DIST */
1637 1.1 paulus s->block_start -= (long) wsize;
1638 1.1 paulus
1639 1.1 paulus /* Slide the hash table (could be avoided with 32 bit values
1640 1.7 christos at the expense of memory usage). We slide even when level == 0
1641 1.7 christos to keep the hash table consistent if we switch back to level > 0
1642 1.7 christos later. (Using level 0 permanently is not an optimal usage of
1643 1.7 christos zlib, so we don't care about this pathological case.)
1644 1.1 paulus */
1645 1.17 fvdl n = s->hash_size;
1646 1.17 fvdl p = &s->head[n];
1647 1.17 fvdl do {
1648 1.17 fvdl m = *--p;
1649 1.17 fvdl *p = (Pos)(m >= wsize ? m-wsize : NIL);
1650 1.17 fvdl } while (--n);
1651 1.17 fvdl
1652 1.17 fvdl n = wsize;
1653 1.17 fvdl #ifndef FASTEST
1654 1.17 fvdl p = &s->prev[n];
1655 1.17 fvdl do {
1656 1.17 fvdl m = *--p;
1657 1.17 fvdl *p = (Pos)(m >= wsize ? m-wsize : NIL);
1658 1.17 fvdl /* If n is not on any hash chain, prev[n] is garbage but
1659 1.17 fvdl * its value will never be used.
1660 1.17 fvdl */
1661 1.17 fvdl } while (--n);
1662 1.17 fvdl #endif
1663 1.1 paulus more += wsize;
1664 1.1 paulus }
1665 1.1 paulus if (s->strm->avail_in == 0) return;
1666 1.1 paulus
1667 1.1 paulus /* If there was no sliding:
1668 1.1 paulus * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 &&
1669 1.1 paulus * more == window_size - lookahead - strstart
1670 1.1 paulus * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1)
1671 1.1 paulus * => more >= window_size - 2*WSIZE + 2
1672 1.1 paulus * In the BIG_MEM or MMAP case (not yet supported),
1673 1.1 paulus * window_size == input_size + MIN_LOOKAHEAD &&
1674 1.1 paulus * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD.
1675 1.1 paulus * Otherwise, window_size == 2*WSIZE so more >= 2.
1676 1.1 paulus * If there was sliding, more >= WSIZE. So in all cases, more >= 2.
1677 1.1 paulus */
1678 1.1 paulus Assert(more >= 2, "more < 2");
1679 1.1 paulus
1680 1.17 fvdl n = read_buf(s->strm, s->window + s->strstart + s->lookahead, more);
1681 1.1 paulus s->lookahead += n;
1682 1.1 paulus
1683 1.1 paulus /* Initialize the hash value now that we have some input: */
1684 1.1 paulus if (s->lookahead >= MIN_MATCH) {
1685 1.1 paulus s->ins_h = s->window[s->strstart];
1686 1.1 paulus UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
1687 1.1 paulus #if MIN_MATCH != 3
1688 1.1 paulus Call UPDATE_HASH() MIN_MATCH-3 more times
1689 1.1 paulus #endif
1690 1.1 paulus }
1691 1.1 paulus /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage,
1692 1.1 paulus * but this is not important since only literal bytes will be emitted.
1693 1.1 paulus */
1694 1.1 paulus
1695 1.1 paulus } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0);
1696 1.1 paulus }
1697 1.1 paulus
1698 1.1 paulus /* ===========================================================================
1699 1.1 paulus * Flush the current block, with given end-of-file flag.
1700 1.1 paulus * IN assertion: strstart is set to the end of the current match.
1701 1.1 paulus */
1702 1.7 christos #define FLUSH_BLOCK_ONLY(s, eof) { \
1703 1.7 christos _tr_flush_block(s, (s->block_start >= 0L ? \
1704 1.7 christos (charf *)&s->window[(unsigned)s->block_start] : \
1705 1.7 christos (charf *)Z_NULL), \
1706 1.7 christos (ulg)((long)s->strstart - s->block_start), \
1707 1.7 christos (eof)); \
1708 1.1 paulus s->block_start = s->strstart; \
1709 1.1 paulus flush_pending(s->strm); \
1710 1.1 paulus Tracev((stderr,"[FLUSH]")); \
1711 1.1 paulus }
1712 1.1 paulus
1713 1.1 paulus /* Same but force premature exit if necessary. */
1714 1.7 christos #define FLUSH_BLOCK(s, eof) { \
1715 1.7 christos FLUSH_BLOCK_ONLY(s, eof); \
1716 1.7 christos if (s->strm->avail_out == 0) return (eof) ? finish_started : need_more; \
1717 1.7 christos }
1718 1.7 christos
1719 1.7 christos /* ===========================================================================
1720 1.7 christos * Copy without compression as much as possible from the input stream, return
1721 1.7 christos * the current block state.
1722 1.7 christos * This function does not insert new strings in the dictionary since
1723 1.7 christos * uncompressible data is probably not useful. This function is used
1724 1.7 christos * only for the level=0 compression option.
1725 1.7 christos * NOTE: this function should be optimized to avoid extra copying from
1726 1.7 christos * window to pending_buf.
1727 1.7 christos */
1728 1.7 christos local block_state deflate_stored(s, flush)
1729 1.7 christos deflate_state *s;
1730 1.7 christos int flush;
1731 1.7 christos {
1732 1.7 christos /* Stored blocks are limited to 0xffff bytes, pending_buf is limited
1733 1.7 christos * to pending_buf_size, and each stored block has a 5 byte header:
1734 1.7 christos */
1735 1.7 christos ulg max_block_size = 0xffff;
1736 1.7 christos ulg max_start;
1737 1.7 christos
1738 1.7 christos if (max_block_size > s->pending_buf_size - 5) {
1739 1.7 christos max_block_size = s->pending_buf_size - 5;
1740 1.7 christos }
1741 1.7 christos
1742 1.7 christos /* Copy as much as possible from input to output: */
1743 1.7 christos for (;;) {
1744 1.7 christos /* Fill the window as much as possible: */
1745 1.7 christos if (s->lookahead <= 1) {
1746 1.7 christos
1747 1.7 christos Assert(s->strstart < s->w_size+MAX_DIST(s) ||
1748 1.7 christos s->block_start >= (long)s->w_size, "slide too late");
1749 1.7 christos
1750 1.7 christos fill_window(s);
1751 1.7 christos if (s->lookahead == 0 && flush == Z_NO_FLUSH) return need_more;
1752 1.7 christos
1753 1.7 christos if (s->lookahead == 0) break; /* flush the current block */
1754 1.7 christos }
1755 1.7 christos Assert(s->block_start >= 0L, "block gone");
1756 1.7 christos
1757 1.7 christos s->strstart += s->lookahead;
1758 1.7 christos s->lookahead = 0;
1759 1.7 christos
1760 1.7 christos /* Emit a stored block if pending_buf will be full: */
1761 1.7 christos max_start = s->block_start + max_block_size;
1762 1.7 christos if (s->strstart == 0 || (ulg)s->strstart >= max_start) {
1763 1.7 christos /* strstart == 0 is possible when wraparound on 16-bit machine */
1764 1.7 christos s->lookahead = (uInt)(s->strstart - max_start);
1765 1.7 christos s->strstart = (uInt)max_start;
1766 1.7 christos FLUSH_BLOCK(s, 0);
1767 1.7 christos }
1768 1.7 christos /* Flush if we may have to slide, otherwise block_start may become
1769 1.7 christos * negative and the data will be gone:
1770 1.7 christos */
1771 1.7 christos if (s->strstart - (uInt)s->block_start >= MAX_DIST(s)) {
1772 1.7 christos FLUSH_BLOCK(s, 0);
1773 1.7 christos }
1774 1.7 christos }
1775 1.7 christos FLUSH_BLOCK(s, flush == Z_FINISH);
1776 1.7 christos return flush == Z_FINISH ? finish_done : block_done;
1777 1.1 paulus }
1778 1.1 paulus
1779 1.1 paulus /* ===========================================================================
1780 1.7 christos * Compress as much as possible from the input stream, return the current
1781 1.7 christos * block state.
1782 1.7 christos * This function does not perform lazy evaluation of matches and inserts
1783 1.1 paulus * new strings in the dictionary only for unmatched strings or for short
1784 1.1 paulus * matches. It is used only for the fast compression options.
1785 1.1 paulus */
1786 1.7 christos local block_state deflate_fast(s, flush)
1787 1.1 paulus deflate_state *s;
1788 1.1 paulus int flush;
1789 1.1 paulus {
1790 1.1 paulus IPos hash_head = NIL; /* head of the hash chain */
1791 1.7 christos int bflush; /* set if current block must be flushed */
1792 1.1 paulus
1793 1.1 paulus for (;;) {
1794 1.1 paulus /* Make sure that we always have enough lookahead, except
1795 1.1 paulus * at the end of the input file. We need MAX_MATCH bytes
1796 1.1 paulus * for the next match, plus MIN_MATCH bytes to insert the
1797 1.1 paulus * string following the next match.
1798 1.1 paulus */
1799 1.1 paulus if (s->lookahead < MIN_LOOKAHEAD) {
1800 1.1 paulus fill_window(s);
1801 1.7 christos if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
1802 1.7 christos return need_more;
1803 1.7 christos }
1804 1.1 paulus if (s->lookahead == 0) break; /* flush the current block */
1805 1.1 paulus }
1806 1.1 paulus
1807 1.1 paulus /* Insert the string window[strstart .. strstart+2] in the
1808 1.1 paulus * dictionary, and set hash_head to the head of the hash chain:
1809 1.1 paulus */
1810 1.1 paulus if (s->lookahead >= MIN_MATCH) {
1811 1.1 paulus INSERT_STRING(s, s->strstart, hash_head);
1812 1.1 paulus }
1813 1.1 paulus
1814 1.1 paulus /* Find the longest match, discarding those <= prev_length.
1815 1.1 paulus * At this point we have always match_length < MIN_MATCH
1816 1.1 paulus */
1817 1.1 paulus if (hash_head != NIL && s->strstart - hash_head <= MAX_DIST(s)) {
1818 1.1 paulus /* To simplify the code, we prevent matches with the string
1819 1.1 paulus * of window index 0 (in particular we have to avoid a match
1820 1.1 paulus * of the string with itself at the start of the input file).
1821 1.1 paulus */
1822 1.1 paulus if (s->strategy != Z_HUFFMAN_ONLY) {
1823 1.1 paulus s->match_length = longest_match (s, hash_head);
1824 1.1 paulus }
1825 1.1 paulus /* longest_match() sets match_start */
1826 1.1 paulus }
1827 1.1 paulus if (s->match_length >= MIN_MATCH) {
1828 1.1 paulus check_match(s, s->strstart, s->match_start, s->match_length);
1829 1.1 paulus
1830 1.17 fvdl _tr_tally_dist(s, s->strstart - s->match_start,
1831 1.17 fvdl s->match_length - MIN_MATCH, bflush);
1832 1.1 paulus
1833 1.1 paulus s->lookahead -= s->match_length;
1834 1.1 paulus
1835 1.1 paulus /* Insert new strings in the hash table only if the match length
1836 1.1 paulus * is not too large. This saves time but degrades compression.
1837 1.1 paulus */
1838 1.17 fvdl #ifndef FASTEST
1839 1.1 paulus if (s->match_length <= s->max_insert_length &&
1840 1.1 paulus s->lookahead >= MIN_MATCH) {
1841 1.1 paulus s->match_length--; /* string at strstart already in hash table */
1842 1.1 paulus do {
1843 1.1 paulus s->strstart++;
1844 1.1 paulus INSERT_STRING(s, s->strstart, hash_head);
1845 1.1 paulus /* strstart never exceeds WSIZE-MAX_MATCH, so there are
1846 1.1 paulus * always MIN_MATCH bytes ahead.
1847 1.1 paulus */
1848 1.1 paulus } while (--s->match_length != 0);
1849 1.20 perry s->strstart++;
1850 1.17 fvdl } else
1851 1.17 fvdl #endif
1852 1.17 fvdl {
1853 1.1 paulus s->strstart += s->match_length;
1854 1.1 paulus s->match_length = 0;
1855 1.1 paulus s->ins_h = s->window[s->strstart];
1856 1.1 paulus UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
1857 1.1 paulus #if MIN_MATCH != 3
1858 1.1 paulus Call UPDATE_HASH() MIN_MATCH-3 more times
1859 1.1 paulus #endif
1860 1.1 paulus /* If lookahead < MIN_MATCH, ins_h is garbage, but it does not
1861 1.1 paulus * matter since it will be recomputed at next deflate call.
1862 1.1 paulus */
1863 1.1 paulus }
1864 1.1 paulus } else {
1865 1.1 paulus /* No match, output a literal byte */
1866 1.1 paulus Tracevv((stderr,"%c", s->window[s->strstart]));
1867 1.17 fvdl _tr_tally_lit (s, s->window[s->strstart], bflush);
1868 1.1 paulus s->lookahead--;
1869 1.20 perry s->strstart++;
1870 1.1 paulus }
1871 1.7 christos if (bflush) FLUSH_BLOCK(s, 0);
1872 1.1 paulus }
1873 1.7 christos FLUSH_BLOCK(s, flush == Z_FINISH);
1874 1.7 christos return flush == Z_FINISH ? finish_done : block_done;
1875 1.1 paulus }
1876 1.1 paulus
1877 1.1 paulus /* ===========================================================================
1878 1.1 paulus * Same as above, but achieves better compression. We use a lazy
1879 1.1 paulus * evaluation for matches: a match is finally adopted only if there is
1880 1.1 paulus * no better match at the next window position.
1881 1.1 paulus */
1882 1.7 christos local block_state deflate_slow(s, flush)
1883 1.1 paulus deflate_state *s;
1884 1.1 paulus int flush;
1885 1.1 paulus {
1886 1.1 paulus IPos hash_head = NIL; /* head of hash chain */
1887 1.1 paulus int bflush; /* set if current block must be flushed */
1888 1.1 paulus
1889 1.1 paulus /* Process the input block. */
1890 1.1 paulus for (;;) {
1891 1.1 paulus /* Make sure that we always have enough lookahead, except
1892 1.1 paulus * at the end of the input file. We need MAX_MATCH bytes
1893 1.1 paulus * for the next match, plus MIN_MATCH bytes to insert the
1894 1.1 paulus * string following the next match.
1895 1.1 paulus */
1896 1.1 paulus if (s->lookahead < MIN_LOOKAHEAD) {
1897 1.1 paulus fill_window(s);
1898 1.7 christos if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
1899 1.7 christos return need_more;
1900 1.7 christos }
1901 1.1 paulus if (s->lookahead == 0) break; /* flush the current block */
1902 1.1 paulus }
1903 1.1 paulus
1904 1.1 paulus /* Insert the string window[strstart .. strstart+2] in the
1905 1.1 paulus * dictionary, and set hash_head to the head of the hash chain:
1906 1.1 paulus */
1907 1.1 paulus if (s->lookahead >= MIN_MATCH) {
1908 1.1 paulus INSERT_STRING(s, s->strstart, hash_head);
1909 1.1 paulus }
1910 1.1 paulus
1911 1.1 paulus /* Find the longest match, discarding those <= prev_length.
1912 1.1 paulus */
1913 1.1 paulus s->prev_length = s->match_length, s->prev_match = s->match_start;
1914 1.1 paulus s->match_length = MIN_MATCH-1;
1915 1.1 paulus
1916 1.1 paulus if (hash_head != NIL && s->prev_length < s->max_lazy_match &&
1917 1.1 paulus s->strstart - hash_head <= MAX_DIST(s)) {
1918 1.1 paulus /* To simplify the code, we prevent matches with the string
1919 1.1 paulus * of window index 0 (in particular we have to avoid a match
1920 1.1 paulus * of the string with itself at the start of the input file).
1921 1.1 paulus */
1922 1.1 paulus if (s->strategy != Z_HUFFMAN_ONLY) {
1923 1.1 paulus s->match_length = longest_match (s, hash_head);
1924 1.1 paulus }
1925 1.1 paulus /* longest_match() sets match_start */
1926 1.1 paulus
1927 1.1 paulus if (s->match_length <= 5 && (s->strategy == Z_FILTERED ||
1928 1.1 paulus (s->match_length == MIN_MATCH &&
1929 1.1 paulus s->strstart - s->match_start > TOO_FAR))) {
1930 1.1 paulus
1931 1.1 paulus /* If prev_match is also MIN_MATCH, match_start is garbage
1932 1.1 paulus * but we will ignore the current match anyway.
1933 1.1 paulus */
1934 1.1 paulus s->match_length = MIN_MATCH-1;
1935 1.1 paulus }
1936 1.1 paulus }
1937 1.1 paulus /* If there was a match at the previous step and the current
1938 1.1 paulus * match is not better, output the previous match:
1939 1.1 paulus */
1940 1.1 paulus if (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) {
1941 1.1 paulus uInt max_insert = s->strstart + s->lookahead - MIN_MATCH;
1942 1.1 paulus /* Do not insert strings in hash table beyond this. */
1943 1.1 paulus
1944 1.1 paulus check_match(s, s->strstart-1, s->prev_match, s->prev_length);
1945 1.1 paulus
1946 1.17 fvdl _tr_tally_dist(s, s->strstart -1 - s->prev_match,
1947 1.17 fvdl s->prev_length - MIN_MATCH, bflush);
1948 1.1 paulus
1949 1.1 paulus /* Insert in hash table all strings up to the end of the match.
1950 1.1 paulus * strstart-1 and strstart are already inserted. If there is not
1951 1.1 paulus * enough lookahead, the last two strings are not inserted in
1952 1.1 paulus * the hash table.
1953 1.1 paulus */
1954 1.1 paulus s->lookahead -= s->prev_length-1;
1955 1.1 paulus s->prev_length -= 2;
1956 1.1 paulus do {
1957 1.1 paulus if (++s->strstart <= max_insert) {
1958 1.1 paulus INSERT_STRING(s, s->strstart, hash_head);
1959 1.1 paulus }
1960 1.1 paulus } while (--s->prev_length != 0);
1961 1.1 paulus s->match_available = 0;
1962 1.1 paulus s->match_length = MIN_MATCH-1;
1963 1.1 paulus s->strstart++;
1964 1.1 paulus
1965 1.7 christos if (bflush) FLUSH_BLOCK(s, 0);
1966 1.1 paulus
1967 1.1 paulus } else if (s->match_available) {
1968 1.1 paulus /* If there was no match at the previous position, output a
1969 1.1 paulus * single literal. If there was a match but the current match
1970 1.1 paulus * is longer, truncate the previous match to a single literal.
1971 1.1 paulus */
1972 1.1 paulus Tracevv((stderr,"%c", s->window[s->strstart-1]));
1973 1.17 fvdl _tr_tally_lit(s, s->window[s->strstart-1], bflush);
1974 1.17 fvdl if (bflush) {
1975 1.7 christos FLUSH_BLOCK_ONLY(s, 0);
1976 1.1 paulus }
1977 1.1 paulus s->strstart++;
1978 1.1 paulus s->lookahead--;
1979 1.7 christos if (s->strm->avail_out == 0) return need_more;
1980 1.1 paulus } else {
1981 1.1 paulus /* There is no previous match to compare with, wait for
1982 1.1 paulus * the next step to decide.
1983 1.1 paulus */
1984 1.1 paulus s->match_available = 1;
1985 1.1 paulus s->strstart++;
1986 1.1 paulus s->lookahead--;
1987 1.1 paulus }
1988 1.1 paulus }
1989 1.1 paulus Assert (flush != Z_NO_FLUSH, "no flush?");
1990 1.1 paulus if (s->match_available) {
1991 1.1 paulus Tracevv((stderr,"%c", s->window[s->strstart-1]));
1992 1.17 fvdl _tr_tally_lit(s, s->window[s->strstart-1], bflush);
1993 1.1 paulus s->match_available = 0;
1994 1.1 paulus }
1995 1.7 christos FLUSH_BLOCK(s, flush == Z_FINISH);
1996 1.7 christos return flush == Z_FINISH ? finish_done : block_done;
1997 1.1 paulus }
1998 1.7 christos /* --- deflate.c */
1999 1.1 paulus
2000 1.7 christos /* +++ trees.c */
2001 1.17 fvdl
2002 1.1 paulus /* trees.c -- output deflated data using Huffman coding
2003 1.17 fvdl * Copyright (C) 1995-2002 Jean-loup Gailly
2004 1.20 perry * For conditions of distribution and use, see copyright notice in zlib.h
2005 1.1 paulus */
2006 1.1 paulus
2007 1.1 paulus /*
2008 1.1 paulus * ALGORITHM
2009 1.1 paulus *
2010 1.1 paulus * The "deflation" process uses several Huffman trees. The more
2011 1.1 paulus * common source values are represented by shorter bit sequences.
2012 1.1 paulus *
2013 1.1 paulus * Each code tree is stored in a compressed form which is itself
2014 1.1 paulus * a Huffman encoding of the lengths of all the code strings (in
2015 1.1 paulus * ascending order by source values). The actual code strings are
2016 1.1 paulus * reconstructed from the lengths in the inflate process, as described
2017 1.1 paulus * in the deflate specification.
2018 1.1 paulus *
2019 1.1 paulus * REFERENCES
2020 1.1 paulus *
2021 1.1 paulus * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification".
2022 1.1 paulus * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc
2023 1.1 paulus *
2024 1.1 paulus * Storer, James A.
2025 1.1 paulus * Data Compression: Methods and Theory, pp. 49-50.
2026 1.1 paulus * Computer Science Press, 1988. ISBN 0-7167-8156-5.
2027 1.1 paulus *
2028 1.1 paulus * Sedgewick, R.
2029 1.1 paulus * Algorithms, p290.
2030 1.1 paulus * Addison-Wesley, 1983. ISBN 0-201-06672-6.
2031 1.1 paulus */
2032 1.1 paulus
2033 1.27 christos /* @(#) $Id: zlib.c,v 1.27 2006/10/12 01:32:30 christos Exp $ */
2034 1.17 fvdl
2035 1.17 fvdl /* #define GEN_TREES_H */
2036 1.7 christos
2037 1.7 christos /* #include "deflate.h" */
2038 1.1 paulus
2039 1.1 paulus #ifdef DEBUG_ZLIB
2040 1.1 paulus # include <ctype.h>
2041 1.1 paulus #endif
2042 1.1 paulus
2043 1.1 paulus /* ===========================================================================
2044 1.1 paulus * Constants
2045 1.1 paulus */
2046 1.1 paulus
2047 1.1 paulus #define MAX_BL_BITS 7
2048 1.1 paulus /* Bit length codes must not exceed MAX_BL_BITS bits */
2049 1.1 paulus
2050 1.1 paulus #define END_BLOCK 256
2051 1.1 paulus /* end of block literal code */
2052 1.1 paulus
2053 1.1 paulus #define REP_3_6 16
2054 1.1 paulus /* repeat previous bit length 3-6 times (2 bits of repeat count) */
2055 1.1 paulus
2056 1.1 paulus #define REPZ_3_10 17
2057 1.1 paulus /* repeat a zero length 3-10 times (3 bits of repeat count) */
2058 1.1 paulus
2059 1.1 paulus #define REPZ_11_138 18
2060 1.1 paulus /* repeat a zero length 11-138 times (7 bits of repeat count) */
2061 1.1 paulus
2062 1.12 jdolecek local const int extra_lbits[LENGTH_CODES] /* extra bits for each length code */
2063 1.1 paulus = {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};
2064 1.1 paulus
2065 1.12 jdolecek local const int extra_dbits[D_CODES] /* extra bits for each distance code */
2066 1.1 paulus = {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};
2067 1.1 paulus
2068 1.12 jdolecek local const int extra_blbits[BL_CODES]/* extra bits for each bit length code */
2069 1.1 paulus = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7};
2070 1.1 paulus
2071 1.12 jdolecek local const uch bl_order[BL_CODES]
2072 1.1 paulus = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15};
2073 1.1 paulus /* The lengths of the bit length codes are sent in order of decreasing
2074 1.1 paulus * probability, to avoid transmitting the lengths for unused bit length codes.
2075 1.1 paulus */
2076 1.1 paulus
2077 1.1 paulus #define Buf_size (8 * 2*sizeof(char))
2078 1.1 paulus /* Number of bits used within bi_buf. (bi_buf might be implemented on
2079 1.1 paulus * more than 16 bits on some systems.)
2080 1.1 paulus */
2081 1.1 paulus
2082 1.1 paulus /* ===========================================================================
2083 1.1 paulus * Local data. These are initialized only once.
2084 1.1 paulus */
2085 1.1 paulus
2086 1.17 fvdl #define DIST_CODE_LEN 512 /* see definition of array dist_code below */
2087 1.17 fvdl
2088 1.17 fvdl #if defined(GEN_TREES_H) || !defined(STDC)
2089 1.17 fvdl /* non ANSI compilers may not accept trees.h */
2090 1.17 fvdl
2091 1.1 paulus local ct_data static_ltree[L_CODES+2];
2092 1.1 paulus /* The static literal tree. Since the bit lengths are imposed, there is no
2093 1.1 paulus * need for the L_CODES extra codes used during heap construction. However
2094 1.7 christos * The codes 286 and 287 are needed to build a canonical tree (see _tr_init
2095 1.1 paulus * below).
2096 1.1 paulus */
2097 1.1 paulus
2098 1.1 paulus local ct_data static_dtree[D_CODES];
2099 1.1 paulus /* The static distance tree. (Actually a trivial tree since all codes use
2100 1.1 paulus * 5 bits.)
2101 1.1 paulus */
2102 1.1 paulus
2103 1.17 fvdl uch _dist_code[DIST_CODE_LEN];
2104 1.17 fvdl /* Distance codes. The first 256 values correspond to the distances
2105 1.1 paulus * 3 .. 258, the last 256 values correspond to the top 8 bits of
2106 1.1 paulus * the 15 bit distances.
2107 1.1 paulus */
2108 1.1 paulus
2109 1.17 fvdl uch _length_code[MAX_MATCH-MIN_MATCH+1];
2110 1.1 paulus /* length code for each normalized match length (0 == MIN_MATCH) */
2111 1.1 paulus
2112 1.1 paulus local int base_length[LENGTH_CODES];
2113 1.1 paulus /* First normalized length for each code (0 = MIN_MATCH) */
2114 1.1 paulus
2115 1.1 paulus local int base_dist[D_CODES];
2116 1.1 paulus /* First normalized distance for each code (0 = distance of 1) */
2117 1.1 paulus
2118 1.17 fvdl #else
2119 1.17 fvdl /* +++ trees.h */
2120 1.17 fvdl
2121 1.17 fvdl /* header created automatically with -DGEN_TREES_H */
2122 1.17 fvdl
2123 1.17 fvdl local const ct_data static_ltree[L_CODES+2] = {
2124 1.17 fvdl {{ 12},{ 8}}, {{140},{ 8}}, {{ 76},{ 8}}, {{204},{ 8}}, {{ 44},{ 8}},
2125 1.17 fvdl {{172},{ 8}}, {{108},{ 8}}, {{236},{ 8}}, {{ 28},{ 8}}, {{156},{ 8}},
2126 1.17 fvdl {{ 92},{ 8}}, {{220},{ 8}}, {{ 60},{ 8}}, {{188},{ 8}}, {{124},{ 8}},
2127 1.17 fvdl {{252},{ 8}}, {{ 2},{ 8}}, {{130},{ 8}}, {{ 66},{ 8}}, {{194},{ 8}},
2128 1.17 fvdl {{ 34},{ 8}}, {{162},{ 8}}, {{ 98},{ 8}}, {{226},{ 8}}, {{ 18},{ 8}},
2129 1.17 fvdl {{146},{ 8}}, {{ 82},{ 8}}, {{210},{ 8}}, {{ 50},{ 8}}, {{178},{ 8}},
2130 1.17 fvdl {{114},{ 8}}, {{242},{ 8}}, {{ 10},{ 8}}, {{138},{ 8}}, {{ 74},{ 8}},
2131 1.17 fvdl {{202},{ 8}}, {{ 42},{ 8}}, {{170},{ 8}}, {{106},{ 8}}, {{234},{ 8}},
2132 1.17 fvdl {{ 26},{ 8}}, {{154},{ 8}}, {{ 90},{ 8}}, {{218},{ 8}}, {{ 58},{ 8}},
2133 1.17 fvdl {{186},{ 8}}, {{122},{ 8}}, {{250},{ 8}}, {{ 6},{ 8}}, {{134},{ 8}},
2134 1.17 fvdl {{ 70},{ 8}}, {{198},{ 8}}, {{ 38},{ 8}}, {{166},{ 8}}, {{102},{ 8}},
2135 1.17 fvdl {{230},{ 8}}, {{ 22},{ 8}}, {{150},{ 8}}, {{ 86},{ 8}}, {{214},{ 8}},
2136 1.17 fvdl {{ 54},{ 8}}, {{182},{ 8}}, {{118},{ 8}}, {{246},{ 8}}, {{ 14},{ 8}},
2137 1.17 fvdl {{142},{ 8}}, {{ 78},{ 8}}, {{206},{ 8}}, {{ 46},{ 8}}, {{174},{ 8}},
2138 1.17 fvdl {{110},{ 8}}, {{238},{ 8}}, {{ 30},{ 8}}, {{158},{ 8}}, {{ 94},{ 8}},
2139 1.17 fvdl {{222},{ 8}}, {{ 62},{ 8}}, {{190},{ 8}}, {{126},{ 8}}, {{254},{ 8}},
2140 1.17 fvdl {{ 1},{ 8}}, {{129},{ 8}}, {{ 65},{ 8}}, {{193},{ 8}}, {{ 33},{ 8}},
2141 1.17 fvdl {{161},{ 8}}, {{ 97},{ 8}}, {{225},{ 8}}, {{ 17},{ 8}}, {{145},{ 8}},
2142 1.17 fvdl {{ 81},{ 8}}, {{209},{ 8}}, {{ 49},{ 8}}, {{177},{ 8}}, {{113},{ 8}},
2143 1.17 fvdl {{241},{ 8}}, {{ 9},{ 8}}, {{137},{ 8}}, {{ 73},{ 8}}, {{201},{ 8}},
2144 1.17 fvdl {{ 41},{ 8}}, {{169},{ 8}}, {{105},{ 8}}, {{233},{ 8}}, {{ 25},{ 8}},
2145 1.17 fvdl {{153},{ 8}}, {{ 89},{ 8}}, {{217},{ 8}}, {{ 57},{ 8}}, {{185},{ 8}},
2146 1.17 fvdl {{121},{ 8}}, {{249},{ 8}}, {{ 5},{ 8}}, {{133},{ 8}}, {{ 69},{ 8}},
2147 1.17 fvdl {{197},{ 8}}, {{ 37},{ 8}}, {{165},{ 8}}, {{101},{ 8}}, {{229},{ 8}},
2148 1.17 fvdl {{ 21},{ 8}}, {{149},{ 8}}, {{ 85},{ 8}}, {{213},{ 8}}, {{ 53},{ 8}},
2149 1.17 fvdl {{181},{ 8}}, {{117},{ 8}}, {{245},{ 8}}, {{ 13},{ 8}}, {{141},{ 8}},
2150 1.17 fvdl {{ 77},{ 8}}, {{205},{ 8}}, {{ 45},{ 8}}, {{173},{ 8}}, {{109},{ 8}},
2151 1.17 fvdl {{237},{ 8}}, {{ 29},{ 8}}, {{157},{ 8}}, {{ 93},{ 8}}, {{221},{ 8}},
2152 1.17 fvdl {{ 61},{ 8}}, {{189},{ 8}}, {{125},{ 8}}, {{253},{ 8}}, {{ 19},{ 9}},
2153 1.17 fvdl {{275},{ 9}}, {{147},{ 9}}, {{403},{ 9}}, {{ 83},{ 9}}, {{339},{ 9}},
2154 1.17 fvdl {{211},{ 9}}, {{467},{ 9}}, {{ 51},{ 9}}, {{307},{ 9}}, {{179},{ 9}},
2155 1.17 fvdl {{435},{ 9}}, {{115},{ 9}}, {{371},{ 9}}, {{243},{ 9}}, {{499},{ 9}},
2156 1.17 fvdl {{ 11},{ 9}}, {{267},{ 9}}, {{139},{ 9}}, {{395},{ 9}}, {{ 75},{ 9}},
2157 1.17 fvdl {{331},{ 9}}, {{203},{ 9}}, {{459},{ 9}}, {{ 43},{ 9}}, {{299},{ 9}},
2158 1.17 fvdl {{171},{ 9}}, {{427},{ 9}}, {{107},{ 9}}, {{363},{ 9}}, {{235},{ 9}},
2159 1.17 fvdl {{491},{ 9}}, {{ 27},{ 9}}, {{283},{ 9}}, {{155},{ 9}}, {{411},{ 9}},
2160 1.17 fvdl {{ 91},{ 9}}, {{347},{ 9}}, {{219},{ 9}}, {{475},{ 9}}, {{ 59},{ 9}},
2161 1.17 fvdl {{315},{ 9}}, {{187},{ 9}}, {{443},{ 9}}, {{123},{ 9}}, {{379},{ 9}},
2162 1.17 fvdl {{251},{ 9}}, {{507},{ 9}}, {{ 7},{ 9}}, {{263},{ 9}}, {{135},{ 9}},
2163 1.17 fvdl {{391},{ 9}}, {{ 71},{ 9}}, {{327},{ 9}}, {{199},{ 9}}, {{455},{ 9}},
2164 1.17 fvdl {{ 39},{ 9}}, {{295},{ 9}}, {{167},{ 9}}, {{423},{ 9}}, {{103},{ 9}},
2165 1.17 fvdl {{359},{ 9}}, {{231},{ 9}}, {{487},{ 9}}, {{ 23},{ 9}}, {{279},{ 9}},
2166 1.17 fvdl {{151},{ 9}}, {{407},{ 9}}, {{ 87},{ 9}}, {{343},{ 9}}, {{215},{ 9}},
2167 1.17 fvdl {{471},{ 9}}, {{ 55},{ 9}}, {{311},{ 9}}, {{183},{ 9}}, {{439},{ 9}},
2168 1.17 fvdl {{119},{ 9}}, {{375},{ 9}}, {{247},{ 9}}, {{503},{ 9}}, {{ 15},{ 9}},
2169 1.17 fvdl {{271},{ 9}}, {{143},{ 9}}, {{399},{ 9}}, {{ 79},{ 9}}, {{335},{ 9}},
2170 1.17 fvdl {{207},{ 9}}, {{463},{ 9}}, {{ 47},{ 9}}, {{303},{ 9}}, {{175},{ 9}},
2171 1.17 fvdl {{431},{ 9}}, {{111},{ 9}}, {{367},{ 9}}, {{239},{ 9}}, {{495},{ 9}},
2172 1.17 fvdl {{ 31},{ 9}}, {{287},{ 9}}, {{159},{ 9}}, {{415},{ 9}}, {{ 95},{ 9}},
2173 1.17 fvdl {{351},{ 9}}, {{223},{ 9}}, {{479},{ 9}}, {{ 63},{ 9}}, {{319},{ 9}},
2174 1.17 fvdl {{191},{ 9}}, {{447},{ 9}}, {{127},{ 9}}, {{383},{ 9}}, {{255},{ 9}},
2175 1.17 fvdl {{511},{ 9}}, {{ 0},{ 7}}, {{ 64},{ 7}}, {{ 32},{ 7}}, {{ 96},{ 7}},
2176 1.17 fvdl {{ 16},{ 7}}, {{ 80},{ 7}}, {{ 48},{ 7}}, {{112},{ 7}}, {{ 8},{ 7}},
2177 1.17 fvdl {{ 72},{ 7}}, {{ 40},{ 7}}, {{104},{ 7}}, {{ 24},{ 7}}, {{ 88},{ 7}},
2178 1.17 fvdl {{ 56},{ 7}}, {{120},{ 7}}, {{ 4},{ 7}}, {{ 68},{ 7}}, {{ 36},{ 7}},
2179 1.17 fvdl {{100},{ 7}}, {{ 20},{ 7}}, {{ 84},{ 7}}, {{ 52},{ 7}}, {{116},{ 7}},
2180 1.17 fvdl {{ 3},{ 8}}, {{131},{ 8}}, {{ 67},{ 8}}, {{195},{ 8}}, {{ 35},{ 8}},
2181 1.17 fvdl {{163},{ 8}}, {{ 99},{ 8}}, {{227},{ 8}}
2182 1.17 fvdl };
2183 1.17 fvdl
2184 1.17 fvdl local const ct_data static_dtree[D_CODES] = {
2185 1.17 fvdl {{ 0},{ 5}}, {{16},{ 5}}, {{ 8},{ 5}}, {{24},{ 5}}, {{ 4},{ 5}},
2186 1.17 fvdl {{20},{ 5}}, {{12},{ 5}}, {{28},{ 5}}, {{ 2},{ 5}}, {{18},{ 5}},
2187 1.17 fvdl {{10},{ 5}}, {{26},{ 5}}, {{ 6},{ 5}}, {{22},{ 5}}, {{14},{ 5}},
2188 1.17 fvdl {{30},{ 5}}, {{ 1},{ 5}}, {{17},{ 5}}, {{ 9},{ 5}}, {{25},{ 5}},
2189 1.17 fvdl {{ 5},{ 5}}, {{21},{ 5}}, {{13},{ 5}}, {{29},{ 5}}, {{ 3},{ 5}},
2190 1.17 fvdl {{19},{ 5}}, {{11},{ 5}}, {{27},{ 5}}, {{ 7},{ 5}}, {{23},{ 5}}
2191 1.17 fvdl };
2192 1.17 fvdl
2193 1.17 fvdl const uch _dist_code[DIST_CODE_LEN] = {
2194 1.17 fvdl 0, 1, 2, 3, 4, 4, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8, 8,
2195 1.17 fvdl 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 10,
2196 1.17 fvdl 10, 10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11,
2197 1.17 fvdl 11, 11, 11, 11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
2198 1.17 fvdl 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 13, 13, 13, 13,
2199 1.17 fvdl 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13,
2200 1.17 fvdl 13, 13, 13, 13, 13, 13, 13, 13, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
2201 1.17 fvdl 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
2202 1.17 fvdl 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
2203 1.17 fvdl 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 15, 15, 15, 15, 15, 15, 15, 15,
2204 1.17 fvdl 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
2205 1.17 fvdl 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
2206 1.17 fvdl 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 0, 0, 16, 17,
2207 1.17 fvdl 18, 18, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 22, 22, 22, 22, 22, 22, 22, 22,
2208 1.17 fvdl 23, 23, 23, 23, 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
2209 1.17 fvdl 24, 24, 24, 24, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
2210 1.17 fvdl 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
2211 1.17 fvdl 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 27, 27, 27, 27, 27, 27, 27, 27,
2212 1.17 fvdl 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
2213 1.17 fvdl 27, 27, 27, 27, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
2214 1.17 fvdl 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
2215 1.17 fvdl 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
2216 1.17 fvdl 28, 28, 28, 28, 28, 28, 28, 28, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
2217 1.17 fvdl 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
2218 1.17 fvdl 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
2219 1.17 fvdl 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29
2220 1.17 fvdl };
2221 1.17 fvdl
2222 1.17 fvdl const uch _length_code[MAX_MATCH-MIN_MATCH+1]= {
2223 1.17 fvdl 0, 1, 2, 3, 4, 5, 6, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 12, 12,
2224 1.17 fvdl 13, 13, 13, 13, 14, 14, 14, 14, 15, 15, 15, 15, 16, 16, 16, 16, 16, 16, 16, 16,
2225 1.17 fvdl 17, 17, 17, 17, 17, 17, 17, 17, 18, 18, 18, 18, 18, 18, 18, 18, 19, 19, 19, 19,
2226 1.17 fvdl 19, 19, 19, 19, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20,
2227 1.17 fvdl 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 22, 22, 22, 22,
2228 1.17 fvdl 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 23, 23, 23, 23, 23, 23, 23, 23,
2229 1.17 fvdl 23, 23, 23, 23, 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
2230 1.17 fvdl 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
2231 1.17 fvdl 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
2232 1.17 fvdl 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 26, 26, 26, 26, 26, 26, 26, 26,
2233 1.17 fvdl 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
2234 1.17 fvdl 26, 26, 26, 26, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
2235 1.17 fvdl 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 28
2236 1.17 fvdl };
2237 1.17 fvdl
2238 1.17 fvdl local const int base_length[LENGTH_CODES] = {
2239 1.17 fvdl 0, 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, 16, 20, 24, 28, 32, 40, 48, 56,
2240 1.17 fvdl 64, 80, 96, 112, 128, 160, 192, 224, 0
2241 1.17 fvdl };
2242 1.17 fvdl
2243 1.17 fvdl local const int base_dist[D_CODES] = {
2244 1.17 fvdl 0, 1, 2, 3, 4, 6, 8, 12, 16, 24,
2245 1.17 fvdl 32, 48, 64, 96, 128, 192, 256, 384, 512, 768,
2246 1.17 fvdl 1024, 1536, 2048, 3072, 4096, 6144, 8192, 12288, 16384, 24576
2247 1.17 fvdl };
2248 1.17 fvdl /* --- trees.h */
2249 1.17 fvdl
2250 1.17 fvdl #endif /* GEN_TREES_H */
2251 1.17 fvdl
2252 1.1 paulus struct static_tree_desc_s {
2253 1.17 fvdl const ct_data *static_tree; /* static tree or NULL */
2254 1.17 fvdl const intf *extra_bits; /* extra bits for each code or NULL */
2255 1.1 paulus int extra_base; /* base index for extra_bits */
2256 1.1 paulus int elems; /* max number of elements in the tree */
2257 1.1 paulus int max_length; /* max bit length for the codes */
2258 1.1 paulus };
2259 1.1 paulus
2260 1.1 paulus local static_tree_desc static_l_desc =
2261 1.1 paulus {static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS};
2262 1.1 paulus
2263 1.1 paulus local static_tree_desc static_d_desc =
2264 1.1 paulus {static_dtree, extra_dbits, 0, D_CODES, MAX_BITS};
2265 1.1 paulus
2266 1.1 paulus local static_tree_desc static_bl_desc =
2267 1.17 fvdl {(const ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS};
2268 1.1 paulus
2269 1.1 paulus /* ===========================================================================
2270 1.1 paulus * Local (static) routines in this file.
2271 1.1 paulus */
2272 1.1 paulus
2273 1.17 fvdl local void tr_static_init __P((void));
2274 1.17 fvdl local void init_block __P((deflate_state *s));
2275 1.17 fvdl local void pqdownheap __P((deflate_state *s, ct_data *tree, int k));
2276 1.17 fvdl local void gen_bitlen __P((deflate_state *s, tree_desc *desc));
2277 1.17 fvdl local void gen_codes __P((ct_data *tree, int max_code, ushf *bl_count));
2278 1.17 fvdl local void build_tree __P((deflate_state *s, tree_desc *desc));
2279 1.17 fvdl local void scan_tree __P((deflate_state *s, ct_data *tree, int max_code));
2280 1.17 fvdl local void send_tree __P((deflate_state *s, ct_data *tree, int max_code));
2281 1.17 fvdl local int build_bl_tree __P((deflate_state *s));
2282 1.17 fvdl local void send_all_trees __P((deflate_state *s, int lcodes, int dcodes,
2283 1.1 paulus int blcodes));
2284 1.21 christos local void compress_block __P((deflate_state *s, const ct_data *ltree,
2285 1.21 christos const ct_data *dtree));
2286 1.17 fvdl local void set_data_type __P((deflate_state *s));
2287 1.17 fvdl local unsigned bi_reverse __P((unsigned value, int length));
2288 1.17 fvdl local void bi_windup __P((deflate_state *s));
2289 1.17 fvdl local void bi_flush __P((deflate_state *s));
2290 1.17 fvdl local void copy_block __P((deflate_state *s, charf *buf, unsigned len,
2291 1.1 paulus int header));
2292 1.1 paulus
2293 1.17 fvdl #ifdef GEN_TREES_H
2294 1.17 fvdl local void gen_trees_header __P((void));
2295 1.17 fvdl #endif
2296 1.17 fvdl
2297 1.1 paulus #ifndef DEBUG_ZLIB
2298 1.1 paulus # define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len)
2299 1.1 paulus /* Send a code of the given tree. c and tree must not have side effects */
2300 1.1 paulus
2301 1.1 paulus #else /* DEBUG_ZLIB */
2302 1.1 paulus # define send_code(s, c, tree) \
2303 1.17 fvdl { if (z_verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \
2304 1.1 paulus send_bits(s, tree[c].Code, tree[c].Len); }
2305 1.1 paulus #endif
2306 1.1 paulus
2307 1.1 paulus /* ===========================================================================
2308 1.1 paulus * Output a short LSB first on the stream.
2309 1.1 paulus * IN assertion: there is enough room in pendingBuf.
2310 1.1 paulus */
2311 1.1 paulus #define put_short(s, w) { \
2312 1.1 paulus put_byte(s, (uch)((w) & 0xff)); \
2313 1.1 paulus put_byte(s, (uch)((ush)(w) >> 8)); \
2314 1.1 paulus }
2315 1.1 paulus
2316 1.1 paulus /* ===========================================================================
2317 1.1 paulus * Send a value on a given number of bits.
2318 1.1 paulus * IN assertion: length <= 16 and value fits in length bits.
2319 1.1 paulus */
2320 1.1 paulus #ifdef DEBUG_ZLIB
2321 1.17 fvdl local void send_bits __P((deflate_state *s, int value, int length));
2322 1.1 paulus
2323 1.1 paulus local void send_bits(s, value, length)
2324 1.1 paulus deflate_state *s;
2325 1.1 paulus int value; /* value to send */
2326 1.1 paulus int length; /* number of bits */
2327 1.1 paulus {
2328 1.7 christos Tracevv((stderr," l %2d v %4x ", length, value));
2329 1.1 paulus Assert(length > 0 && length <= 15, "invalid length");
2330 1.1 paulus s->bits_sent += (ulg)length;
2331 1.1 paulus
2332 1.1 paulus /* If not enough room in bi_buf, use (valid) bits from bi_buf and
2333 1.1 paulus * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid))
2334 1.1 paulus * unused bits in value.
2335 1.1 paulus */
2336 1.1 paulus if (s->bi_valid > (int)Buf_size - length) {
2337 1.1 paulus s->bi_buf |= (value << s->bi_valid);
2338 1.1 paulus put_short(s, s->bi_buf);
2339 1.1 paulus s->bi_buf = (ush)value >> (Buf_size - s->bi_valid);
2340 1.1 paulus s->bi_valid += length - Buf_size;
2341 1.1 paulus } else {
2342 1.1 paulus s->bi_buf |= value << s->bi_valid;
2343 1.1 paulus s->bi_valid += length;
2344 1.1 paulus }
2345 1.1 paulus }
2346 1.1 paulus #else /* !DEBUG_ZLIB */
2347 1.1 paulus
2348 1.1 paulus #define send_bits(s, value, length) \
2349 1.1 paulus { int len = length;\
2350 1.1 paulus if (s->bi_valid > (int)Buf_size - len) {\
2351 1.1 paulus int val = value;\
2352 1.1 paulus s->bi_buf |= (val << s->bi_valid);\
2353 1.1 paulus put_short(s, s->bi_buf);\
2354 1.1 paulus s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\
2355 1.1 paulus s->bi_valid += len - Buf_size;\
2356 1.1 paulus } else {\
2357 1.1 paulus s->bi_buf |= (value) << s->bi_valid;\
2358 1.1 paulus s->bi_valid += len;\
2359 1.1 paulus }\
2360 1.1 paulus }
2361 1.1 paulus #endif /* DEBUG_ZLIB */
2362 1.1 paulus
2363 1.17 fvdl
2364 1.1 paulus /* ===========================================================================
2365 1.17 fvdl * Initialize the various 'constant' tables.
2366 1.1 paulus */
2367 1.7 christos local void tr_static_init()
2368 1.1 paulus {
2369 1.17 fvdl #if defined(GEN_TREES_H) || !defined(STDC)
2370 1.7 christos static int static_init_done = 0;
2371 1.1 paulus int n; /* iterates over tree elements */
2372 1.1 paulus int bits; /* bit counter */
2373 1.1 paulus int length; /* length value */
2374 1.1 paulus int code; /* code value */
2375 1.1 paulus int dist; /* distance index */
2376 1.1 paulus ush bl_count[MAX_BITS+1];
2377 1.1 paulus /* number of codes at each bit length for an optimal tree */
2378 1.1 paulus
2379 1.7 christos if (static_init_done) return;
2380 1.7 christos
2381 1.17 fvdl /* For some embedded targets, global variables are not initialized: */
2382 1.17 fvdl static_l_desc.static_tree = static_ltree;
2383 1.17 fvdl static_l_desc.extra_bits = extra_lbits;
2384 1.17 fvdl static_d_desc.static_tree = static_dtree;
2385 1.17 fvdl static_d_desc.extra_bits = extra_dbits;
2386 1.17 fvdl static_bl_desc.extra_bits = extra_blbits;
2387 1.17 fvdl
2388 1.1 paulus /* Initialize the mapping length (0..255) -> length code (0..28) */
2389 1.1 paulus length = 0;
2390 1.1 paulus for (code = 0; code < LENGTH_CODES-1; code++) {
2391 1.1 paulus base_length[code] = length;
2392 1.1 paulus for (n = 0; n < (1<<extra_lbits[code]); n++) {
2393 1.17 fvdl _length_code[length++] = (uch)code;
2394 1.1 paulus }
2395 1.1 paulus }
2396 1.7 christos Assert (length == 256, "tr_static_init: length != 256");
2397 1.1 paulus /* Note that the length 255 (match length 258) can be represented
2398 1.1 paulus * in two different ways: code 284 + 5 bits or code 285, so we
2399 1.1 paulus * overwrite length_code[255] to use the best encoding:
2400 1.1 paulus */
2401 1.17 fvdl _length_code[length-1] = (uch)code;
2402 1.1 paulus
2403 1.1 paulus /* Initialize the mapping dist (0..32K) -> dist code (0..29) */
2404 1.1 paulus dist = 0;
2405 1.1 paulus for (code = 0 ; code < 16; code++) {
2406 1.1 paulus base_dist[code] = dist;
2407 1.1 paulus for (n = 0; n < (1<<extra_dbits[code]); n++) {
2408 1.17 fvdl _dist_code[dist++] = (uch)code;
2409 1.1 paulus }
2410 1.1 paulus }
2411 1.7 christos Assert (dist == 256, "tr_static_init: dist != 256");
2412 1.1 paulus dist >>= 7; /* from now on, all distances are divided by 128 */
2413 1.1 paulus for ( ; code < D_CODES; code++) {
2414 1.1 paulus base_dist[code] = dist << 7;
2415 1.1 paulus for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) {
2416 1.17 fvdl _dist_code[256 + dist++] = (uch)code;
2417 1.1 paulus }
2418 1.1 paulus }
2419 1.7 christos Assert (dist == 256, "tr_static_init: 256+dist != 512");
2420 1.1 paulus
2421 1.1 paulus /* Construct the codes of the static literal tree */
2422 1.1 paulus for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
2423 1.1 paulus n = 0;
2424 1.1 paulus while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++;
2425 1.1 paulus while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++;
2426 1.1 paulus while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++;
2427 1.1 paulus while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++;
2428 1.1 paulus /* Codes 286 and 287 do not exist, but we must include them in the
2429 1.1 paulus * tree construction to get a canonical Huffman tree (longest code
2430 1.1 paulus * all ones)
2431 1.1 paulus */
2432 1.1 paulus gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count);
2433 1.1 paulus
2434 1.1 paulus /* The static distance tree is trivial: */
2435 1.1 paulus for (n = 0; n < D_CODES; n++) {
2436 1.1 paulus static_dtree[n].Len = 5;
2437 1.7 christos static_dtree[n].Code = bi_reverse((unsigned)n, 5);
2438 1.1 paulus }
2439 1.7 christos static_init_done = 1;
2440 1.17 fvdl
2441 1.17 fvdl # ifdef GEN_TREES_H
2442 1.17 fvdl gen_trees_header();
2443 1.17 fvdl # endif
2444 1.17 fvdl #endif /* defined(GEN_TREES_H) || !defined(STDC) */
2445 1.1 paulus }
2446 1.1 paulus
2447 1.1 paulus /* ===========================================================================
2448 1.17 fvdl * Genererate the file trees.h describing the static trees.
2449 1.17 fvdl */
2450 1.17 fvdl #ifdef GEN_TREES_H
2451 1.17 fvdl # ifndef DEBUG_ZLIB
2452 1.17 fvdl # include <stdio.h>
2453 1.17 fvdl # endif
2454 1.17 fvdl
2455 1.17 fvdl # define SEPARATOR(i, last, width) \
2456 1.17 fvdl ((i) == (last)? "\n};\n\n" : \
2457 1.17 fvdl ((i) % (width) == (width)-1 ? ",\n" : ", "))
2458 1.17 fvdl
2459 1.17 fvdl void gen_trees_header()
2460 1.17 fvdl {
2461 1.17 fvdl FILE *header = fopen("trees.h", "w");
2462 1.17 fvdl int i;
2463 1.17 fvdl
2464 1.17 fvdl Assert (header != NULL, "Can't open trees.h");
2465 1.17 fvdl fprintf(header,
2466 1.17 fvdl "/* header created automatically with -DGEN_TREES_H */\n\n");
2467 1.17 fvdl
2468 1.17 fvdl fprintf(header, "local const ct_data static_ltree[L_CODES+2] = {\n");
2469 1.17 fvdl for (i = 0; i < L_CODES+2; i++) {
2470 1.17 fvdl fprintf(header, "{{%3u},{%3u}}%s", static_ltree[i].Code,
2471 1.17 fvdl static_ltree[i].Len, SEPARATOR(i, L_CODES+1, 5));
2472 1.17 fvdl }
2473 1.17 fvdl
2474 1.17 fvdl fprintf(header, "local const ct_data static_dtree[D_CODES] = {\n");
2475 1.17 fvdl for (i = 0; i < D_CODES; i++) {
2476 1.17 fvdl fprintf(header, "{{%2u},{%2u}}%s", static_dtree[i].Code,
2477 1.17 fvdl static_dtree[i].Len, SEPARATOR(i, D_CODES-1, 5));
2478 1.17 fvdl }
2479 1.17 fvdl
2480 1.17 fvdl fprintf(header, "const uch _dist_code[DIST_CODE_LEN] = {\n");
2481 1.17 fvdl for (i = 0; i < DIST_CODE_LEN; i++) {
2482 1.17 fvdl fprintf(header, "%2u%s", _dist_code[i],
2483 1.17 fvdl SEPARATOR(i, DIST_CODE_LEN-1, 20));
2484 1.17 fvdl }
2485 1.17 fvdl
2486 1.17 fvdl fprintf(header, "const uch _length_code[MAX_MATCH-MIN_MATCH+1]= {\n");
2487 1.17 fvdl for (i = 0; i < MAX_MATCH-MIN_MATCH+1; i++) {
2488 1.17 fvdl fprintf(header, "%2u%s", _length_code[i],
2489 1.17 fvdl SEPARATOR(i, MAX_MATCH-MIN_MATCH, 20));
2490 1.17 fvdl }
2491 1.17 fvdl
2492 1.17 fvdl fprintf(header, "local const int base_length[LENGTH_CODES] = {\n");
2493 1.17 fvdl for (i = 0; i < LENGTH_CODES; i++) {
2494 1.17 fvdl fprintf(header, "%1u%s", base_length[i],
2495 1.17 fvdl SEPARATOR(i, LENGTH_CODES-1, 20));
2496 1.17 fvdl }
2497 1.17 fvdl
2498 1.17 fvdl fprintf(header, "local const int base_dist[D_CODES] = {\n");
2499 1.17 fvdl for (i = 0; i < D_CODES; i++) {
2500 1.17 fvdl fprintf(header, "%5u%s", base_dist[i],
2501 1.17 fvdl SEPARATOR(i, D_CODES-1, 10));
2502 1.17 fvdl }
2503 1.17 fvdl
2504 1.17 fvdl fclose(header);
2505 1.17 fvdl }
2506 1.17 fvdl #endif /* GEN_TREES_H */
2507 1.17 fvdl
2508 1.17 fvdl /* ===========================================================================
2509 1.1 paulus * Initialize the tree data structures for a new zlib stream.
2510 1.1 paulus */
2511 1.7 christos void _tr_init(s)
2512 1.1 paulus deflate_state *s;
2513 1.1 paulus {
2514 1.7 christos tr_static_init();
2515 1.1 paulus
2516 1.1 paulus s->l_desc.dyn_tree = s->dyn_ltree;
2517 1.1 paulus s->l_desc.stat_desc = &static_l_desc;
2518 1.1 paulus
2519 1.1 paulus s->d_desc.dyn_tree = s->dyn_dtree;
2520 1.1 paulus s->d_desc.stat_desc = &static_d_desc;
2521 1.1 paulus
2522 1.1 paulus s->bl_desc.dyn_tree = s->bl_tree;
2523 1.1 paulus s->bl_desc.stat_desc = &static_bl_desc;
2524 1.1 paulus
2525 1.1 paulus s->bi_buf = 0;
2526 1.1 paulus s->bi_valid = 0;
2527 1.1 paulus s->last_eob_len = 8; /* enough lookahead for inflate */
2528 1.1 paulus #ifdef DEBUG_ZLIB
2529 1.17 fvdl s->compressed_len = 0L;
2530 1.1 paulus s->bits_sent = 0L;
2531 1.1 paulus #endif
2532 1.1 paulus
2533 1.1 paulus /* Initialize the first block of the first file: */
2534 1.1 paulus init_block(s);
2535 1.1 paulus }
2536 1.1 paulus
2537 1.1 paulus /* ===========================================================================
2538 1.1 paulus * Initialize a new block.
2539 1.1 paulus */
2540 1.1 paulus local void init_block(s)
2541 1.1 paulus deflate_state *s;
2542 1.1 paulus {
2543 1.1 paulus int n; /* iterates over tree elements */
2544 1.1 paulus
2545 1.1 paulus /* Initialize the trees. */
2546 1.1 paulus for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0;
2547 1.1 paulus for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0;
2548 1.1 paulus for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0;
2549 1.1 paulus
2550 1.1 paulus s->dyn_ltree[END_BLOCK].Freq = 1;
2551 1.1 paulus s->opt_len = s->static_len = 0L;
2552 1.1 paulus s->last_lit = s->matches = 0;
2553 1.1 paulus }
2554 1.1 paulus
2555 1.1 paulus #define SMALLEST 1
2556 1.1 paulus /* Index within the heap array of least frequent node in the Huffman tree */
2557 1.1 paulus
2558 1.1 paulus
2559 1.1 paulus /* ===========================================================================
2560 1.1 paulus * Remove the smallest element from the heap and recreate the heap with
2561 1.1 paulus * one less element. Updates heap and heap_len.
2562 1.1 paulus */
2563 1.1 paulus #define pqremove(s, tree, top) \
2564 1.1 paulus {\
2565 1.1 paulus top = s->heap[SMALLEST]; \
2566 1.1 paulus s->heap[SMALLEST] = s->heap[s->heap_len--]; \
2567 1.1 paulus pqdownheap(s, tree, SMALLEST); \
2568 1.1 paulus }
2569 1.1 paulus
2570 1.1 paulus /* ===========================================================================
2571 1.1 paulus * Compares to subtrees, using the tree depth as tie breaker when
2572 1.1 paulus * the subtrees have equal frequency. This minimizes the worst case length.
2573 1.1 paulus */
2574 1.1 paulus #define smaller(tree, n, m, depth) \
2575 1.1 paulus (tree[n].Freq < tree[m].Freq || \
2576 1.1 paulus (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m]))
2577 1.1 paulus
2578 1.1 paulus /* ===========================================================================
2579 1.1 paulus * Restore the heap property by moving down the tree starting at node k,
2580 1.1 paulus * exchanging a node with the smallest of its two sons if necessary, stopping
2581 1.1 paulus * when the heap property is re-established (each father smaller than its
2582 1.1 paulus * two sons).
2583 1.1 paulus */
2584 1.1 paulus local void pqdownheap(s, tree, k)
2585 1.1 paulus deflate_state *s;
2586 1.1 paulus ct_data *tree; /* the tree to restore */
2587 1.1 paulus int k; /* node to move down */
2588 1.1 paulus {
2589 1.1 paulus int v = s->heap[k];
2590 1.1 paulus int j = k << 1; /* left son of k */
2591 1.1 paulus while (j <= s->heap_len) {
2592 1.1 paulus /* Set j to the smallest of the two sons: */
2593 1.1 paulus if (j < s->heap_len &&
2594 1.1 paulus smaller(tree, s->heap[j+1], s->heap[j], s->depth)) {
2595 1.1 paulus j++;
2596 1.1 paulus }
2597 1.1 paulus /* Exit if v is smaller than both sons */
2598 1.1 paulus if (smaller(tree, v, s->heap[j], s->depth)) break;
2599 1.1 paulus
2600 1.1 paulus /* Exchange v with the smallest son */
2601 1.1 paulus s->heap[k] = s->heap[j]; k = j;
2602 1.1 paulus
2603 1.1 paulus /* And continue down the tree, setting j to the left son of k */
2604 1.1 paulus j <<= 1;
2605 1.1 paulus }
2606 1.1 paulus s->heap[k] = v;
2607 1.1 paulus }
2608 1.1 paulus
2609 1.1 paulus /* ===========================================================================
2610 1.1 paulus * Compute the optimal bit lengths for a tree and update the total bit length
2611 1.1 paulus * for the current block.
2612 1.1 paulus * IN assertion: the fields freq and dad are set, heap[heap_max] and
2613 1.1 paulus * above are the tree nodes sorted by increasing frequency.
2614 1.1 paulus * OUT assertions: the field len is set to the optimal bit length, the
2615 1.1 paulus * array bl_count contains the frequencies for each bit length.
2616 1.1 paulus * The length opt_len is updated; static_len is also updated if stree is
2617 1.1 paulus * not null.
2618 1.1 paulus */
2619 1.1 paulus local void gen_bitlen(s, desc)
2620 1.1 paulus deflate_state *s;
2621 1.1 paulus tree_desc *desc; /* the tree descriptor */
2622 1.1 paulus {
2623 1.17 fvdl ct_data *tree = desc->dyn_tree;
2624 1.17 fvdl int max_code = desc->max_code;
2625 1.17 fvdl const ct_data *stree = desc->stat_desc->static_tree;
2626 1.12 jdolecek const intf *extra = desc->stat_desc->extra_bits;
2627 1.17 fvdl int base = desc->stat_desc->extra_base;
2628 1.17 fvdl int max_length = desc->stat_desc->max_length;
2629 1.1 paulus int h; /* heap index */
2630 1.1 paulus int n, m; /* iterate over the tree elements */
2631 1.1 paulus int bits; /* bit length */
2632 1.1 paulus int xbits; /* extra bits */
2633 1.1 paulus ush f; /* frequency */
2634 1.1 paulus int overflow = 0; /* number of elements with bit length too large */
2635 1.1 paulus
2636 1.1 paulus for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0;
2637 1.1 paulus
2638 1.1 paulus /* In a first pass, compute the optimal bit lengths (which may
2639 1.1 paulus * overflow in the case of the bit length tree).
2640 1.1 paulus */
2641 1.1 paulus tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */
2642 1.1 paulus
2643 1.1 paulus for (h = s->heap_max+1; h < HEAP_SIZE; h++) {
2644 1.1 paulus n = s->heap[h];
2645 1.1 paulus bits = tree[tree[n].Dad].Len + 1;
2646 1.1 paulus if (bits > max_length) bits = max_length, overflow++;
2647 1.1 paulus tree[n].Len = (ush)bits;
2648 1.1 paulus /* We overwrite tree[n].Dad which is no longer needed */
2649 1.1 paulus
2650 1.1 paulus if (n > max_code) continue; /* not a leaf node */
2651 1.1 paulus
2652 1.1 paulus s->bl_count[bits]++;
2653 1.1 paulus xbits = 0;
2654 1.1 paulus if (n >= base) xbits = extra[n-base];
2655 1.1 paulus f = tree[n].Freq;
2656 1.1 paulus s->opt_len += (ulg)f * (bits + xbits);
2657 1.1 paulus if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits);
2658 1.1 paulus }
2659 1.1 paulus if (overflow == 0) return;
2660 1.1 paulus
2661 1.1 paulus Trace((stderr,"\nbit length overflow\n"));
2662 1.1 paulus /* This happens for example on obj2 and pic of the Calgary corpus */
2663 1.1 paulus
2664 1.1 paulus /* Find the first bit length which could increase: */
2665 1.1 paulus do {
2666 1.1 paulus bits = max_length-1;
2667 1.1 paulus while (s->bl_count[bits] == 0) bits--;
2668 1.1 paulus s->bl_count[bits]--; /* move one leaf down the tree */
2669 1.1 paulus s->bl_count[bits+1] += 2; /* move one overflow item as its brother */
2670 1.1 paulus s->bl_count[max_length]--;
2671 1.1 paulus /* The brother of the overflow item also moves one step up,
2672 1.1 paulus * but this does not affect bl_count[max_length]
2673 1.1 paulus */
2674 1.1 paulus overflow -= 2;
2675 1.1 paulus } while (overflow > 0);
2676 1.1 paulus
2677 1.1 paulus /* Now recompute all bit lengths, scanning in increasing frequency.
2678 1.1 paulus * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
2679 1.1 paulus * lengths instead of fixing only the wrong ones. This idea is taken
2680 1.1 paulus * from 'ar' written by Haruhiko Okumura.)
2681 1.1 paulus */
2682 1.1 paulus for (bits = max_length; bits != 0; bits--) {
2683 1.1 paulus n = s->bl_count[bits];
2684 1.1 paulus while (n != 0) {
2685 1.1 paulus m = s->heap[--h];
2686 1.1 paulus if (m > max_code) continue;
2687 1.1 paulus if (tree[m].Len != (unsigned) bits) {
2688 1.1 paulus Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits));
2689 1.1 paulus s->opt_len += ((long)bits - (long)tree[m].Len)
2690 1.1 paulus *(long)tree[m].Freq;
2691 1.1 paulus tree[m].Len = (ush)bits;
2692 1.1 paulus }
2693 1.1 paulus n--;
2694 1.1 paulus }
2695 1.1 paulus }
2696 1.1 paulus }
2697 1.1 paulus
2698 1.1 paulus /* ===========================================================================
2699 1.1 paulus * Generate the codes for a given tree and bit counts (which need not be
2700 1.1 paulus * optimal).
2701 1.1 paulus * IN assertion: the array bl_count contains the bit length statistics for
2702 1.1 paulus * the given tree and the field len is set for all tree elements.
2703 1.1 paulus * OUT assertion: the field code is set for all tree elements of non
2704 1.1 paulus * zero code length.
2705 1.1 paulus */
2706 1.1 paulus local void gen_codes (tree, max_code, bl_count)
2707 1.1 paulus ct_data *tree; /* the tree to decorate */
2708 1.1 paulus int max_code; /* largest code with non zero frequency */
2709 1.1 paulus ushf *bl_count; /* number of codes at each bit length */
2710 1.1 paulus {
2711 1.1 paulus ush next_code[MAX_BITS+1]; /* next code value for each bit length */
2712 1.1 paulus ush code = 0; /* running code value */
2713 1.1 paulus int bits; /* bit index */
2714 1.1 paulus int n; /* code index */
2715 1.1 paulus
2716 1.1 paulus /* The distribution counts are first used to generate the code values
2717 1.1 paulus * without bit reversal.
2718 1.1 paulus */
2719 1.1 paulus for (bits = 1; bits <= MAX_BITS; bits++) {
2720 1.1 paulus next_code[bits] = code = (code + bl_count[bits-1]) << 1;
2721 1.1 paulus }
2722 1.1 paulus /* Check that the bit counts in bl_count are consistent. The last code
2723 1.1 paulus * must be all ones.
2724 1.1 paulus */
2725 1.1 paulus Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1,
2726 1.1 paulus "inconsistent bit counts");
2727 1.1 paulus Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
2728 1.1 paulus
2729 1.1 paulus for (n = 0; n <= max_code; n++) {
2730 1.1 paulus int len = tree[n].Len;
2731 1.1 paulus if (len == 0) continue;
2732 1.1 paulus /* Now reverse the bits */
2733 1.1 paulus tree[n].Code = bi_reverse(next_code[len]++, len);
2734 1.1 paulus
2735 1.7 christos Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
2736 1.1 paulus n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1));
2737 1.1 paulus }
2738 1.1 paulus }
2739 1.1 paulus
2740 1.1 paulus /* ===========================================================================
2741 1.1 paulus * Construct one Huffman tree and assigns the code bit strings and lengths.
2742 1.1 paulus * Update the total bit length for the current block.
2743 1.1 paulus * IN assertion: the field freq is set for all tree elements.
2744 1.1 paulus * OUT assertions: the fields len and code are set to the optimal bit length
2745 1.1 paulus * and corresponding code. The length opt_len is updated; static_len is
2746 1.1 paulus * also updated if stree is not null. The field max_code is set.
2747 1.1 paulus */
2748 1.1 paulus local void build_tree(s, desc)
2749 1.1 paulus deflate_state *s;
2750 1.1 paulus tree_desc *desc; /* the tree descriptor */
2751 1.1 paulus {
2752 1.17 fvdl ct_data *tree = desc->dyn_tree;
2753 1.17 fvdl const ct_data *stree = desc->stat_desc->static_tree;
2754 1.17 fvdl int elems = desc->stat_desc->elems;
2755 1.1 paulus int n, m; /* iterate over heap elements */
2756 1.1 paulus int max_code = -1; /* largest code with non zero frequency */
2757 1.1 paulus int node; /* new node being created */
2758 1.1 paulus
2759 1.1 paulus /* Construct the initial heap, with least frequent element in
2760 1.1 paulus * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
2761 1.1 paulus * heap[0] is not used.
2762 1.1 paulus */
2763 1.1 paulus s->heap_len = 0, s->heap_max = HEAP_SIZE;
2764 1.1 paulus
2765 1.1 paulus for (n = 0; n < elems; n++) {
2766 1.1 paulus if (tree[n].Freq != 0) {
2767 1.1 paulus s->heap[++(s->heap_len)] = max_code = n;
2768 1.1 paulus s->depth[n] = 0;
2769 1.1 paulus } else {
2770 1.1 paulus tree[n].Len = 0;
2771 1.1 paulus }
2772 1.1 paulus }
2773 1.1 paulus
2774 1.1 paulus /* The pkzip format requires that at least one distance code exists,
2775 1.1 paulus * and that at least one bit should be sent even if there is only one
2776 1.1 paulus * possible code. So to avoid special checks later on we force at least
2777 1.1 paulus * two codes of non zero frequency.
2778 1.1 paulus */
2779 1.1 paulus while (s->heap_len < 2) {
2780 1.1 paulus node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0);
2781 1.1 paulus tree[node].Freq = 1;
2782 1.1 paulus s->depth[node] = 0;
2783 1.1 paulus s->opt_len--; if (stree) s->static_len -= stree[node].Len;
2784 1.1 paulus /* node is 0 or 1 so it does not have extra bits */
2785 1.1 paulus }
2786 1.1 paulus desc->max_code = max_code;
2787 1.1 paulus
2788 1.1 paulus /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
2789 1.1 paulus * establish sub-heaps of increasing lengths:
2790 1.1 paulus */
2791 1.1 paulus for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n);
2792 1.1 paulus
2793 1.1 paulus /* Construct the Huffman tree by repeatedly combining the least two
2794 1.1 paulus * frequent nodes.
2795 1.1 paulus */
2796 1.1 paulus node = elems; /* next internal node of the tree */
2797 1.1 paulus do {
2798 1.1 paulus pqremove(s, tree, n); /* n = node of least frequency */
2799 1.1 paulus m = s->heap[SMALLEST]; /* m = node of next least frequency */
2800 1.1 paulus
2801 1.1 paulus s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */
2802 1.1 paulus s->heap[--(s->heap_max)] = m;
2803 1.1 paulus
2804 1.1 paulus /* Create a new node father of n and m */
2805 1.1 paulus tree[node].Freq = tree[n].Freq + tree[m].Freq;
2806 1.1 paulus s->depth[node] = (uch) (MAX(s->depth[n], s->depth[m]) + 1);
2807 1.1 paulus tree[n].Dad = tree[m].Dad = (ush)node;
2808 1.1 paulus #ifdef DUMP_BL_TREE
2809 1.1 paulus if (tree == s->bl_tree) {
2810 1.1 paulus fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)",
2811 1.1 paulus node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq);
2812 1.1 paulus }
2813 1.1 paulus #endif
2814 1.1 paulus /* and insert the new node in the heap */
2815 1.1 paulus s->heap[SMALLEST] = node++;
2816 1.1 paulus pqdownheap(s, tree, SMALLEST);
2817 1.1 paulus
2818 1.1 paulus } while (s->heap_len >= 2);
2819 1.1 paulus
2820 1.1 paulus s->heap[--(s->heap_max)] = s->heap[SMALLEST];
2821 1.1 paulus
2822 1.1 paulus /* At this point, the fields freq and dad are set. We can now
2823 1.1 paulus * generate the bit lengths.
2824 1.1 paulus */
2825 1.1 paulus gen_bitlen(s, (tree_desc *)desc);
2826 1.1 paulus
2827 1.1 paulus /* The field len is now set, we can generate the bit codes */
2828 1.1 paulus gen_codes ((ct_data *)tree, max_code, s->bl_count);
2829 1.1 paulus }
2830 1.1 paulus
2831 1.1 paulus /* ===========================================================================
2832 1.1 paulus * Scan a literal or distance tree to determine the frequencies of the codes
2833 1.1 paulus * in the bit length tree.
2834 1.1 paulus */
2835 1.1 paulus local void scan_tree (s, tree, max_code)
2836 1.1 paulus deflate_state *s;
2837 1.1 paulus ct_data *tree; /* the tree to be scanned */
2838 1.1 paulus int max_code; /* and its largest code of non zero frequency */
2839 1.1 paulus {
2840 1.1 paulus int n; /* iterates over all tree elements */
2841 1.1 paulus int prevlen = -1; /* last emitted length */
2842 1.1 paulus int curlen; /* length of current code */
2843 1.1 paulus int nextlen = tree[0].Len; /* length of next code */
2844 1.1 paulus int count = 0; /* repeat count of the current code */
2845 1.1 paulus int max_count = 7; /* max repeat count */
2846 1.1 paulus int min_count = 4; /* min repeat count */
2847 1.1 paulus
2848 1.1 paulus if (nextlen == 0) max_count = 138, min_count = 3;
2849 1.1 paulus tree[max_code+1].Len = (ush)0xffff; /* guard */
2850 1.1 paulus
2851 1.1 paulus for (n = 0; n <= max_code; n++) {
2852 1.1 paulus curlen = nextlen; nextlen = tree[n+1].Len;
2853 1.1 paulus if (++count < max_count && curlen == nextlen) {
2854 1.1 paulus continue;
2855 1.1 paulus } else if (count < min_count) {
2856 1.1 paulus s->bl_tree[curlen].Freq += count;
2857 1.1 paulus } else if (curlen != 0) {
2858 1.1 paulus if (curlen != prevlen) s->bl_tree[curlen].Freq++;
2859 1.1 paulus s->bl_tree[REP_3_6].Freq++;
2860 1.1 paulus } else if (count <= 10) {
2861 1.1 paulus s->bl_tree[REPZ_3_10].Freq++;
2862 1.1 paulus } else {
2863 1.1 paulus s->bl_tree[REPZ_11_138].Freq++;
2864 1.1 paulus }
2865 1.1 paulus count = 0; prevlen = curlen;
2866 1.1 paulus if (nextlen == 0) {
2867 1.1 paulus max_count = 138, min_count = 3;
2868 1.1 paulus } else if (curlen == nextlen) {
2869 1.1 paulus max_count = 6, min_count = 3;
2870 1.1 paulus } else {
2871 1.1 paulus max_count = 7, min_count = 4;
2872 1.1 paulus }
2873 1.1 paulus }
2874 1.1 paulus }
2875 1.1 paulus
2876 1.1 paulus /* ===========================================================================
2877 1.1 paulus * Send a literal or distance tree in compressed form, using the codes in
2878 1.1 paulus * bl_tree.
2879 1.1 paulus */
2880 1.1 paulus local void send_tree (s, tree, max_code)
2881 1.1 paulus deflate_state *s;
2882 1.1 paulus ct_data *tree; /* the tree to be scanned */
2883 1.1 paulus int max_code; /* and its largest code of non zero frequency */
2884 1.1 paulus {
2885 1.1 paulus int n; /* iterates over all tree elements */
2886 1.1 paulus int prevlen = -1; /* last emitted length */
2887 1.1 paulus int curlen; /* length of current code */
2888 1.1 paulus int nextlen = tree[0].Len; /* length of next code */
2889 1.1 paulus int count = 0; /* repeat count of the current code */
2890 1.1 paulus int max_count = 7; /* max repeat count */
2891 1.1 paulus int min_count = 4; /* min repeat count */
2892 1.1 paulus
2893 1.1 paulus /* tree[max_code+1].Len = -1; */ /* guard already set */
2894 1.1 paulus if (nextlen == 0) max_count = 138, min_count = 3;
2895 1.1 paulus
2896 1.1 paulus for (n = 0; n <= max_code; n++) {
2897 1.1 paulus curlen = nextlen; nextlen = tree[n+1].Len;
2898 1.1 paulus if (++count < max_count && curlen == nextlen) {
2899 1.1 paulus continue;
2900 1.1 paulus } else if (count < min_count) {
2901 1.1 paulus do { send_code(s, curlen, s->bl_tree); } while (--count != 0);
2902 1.1 paulus
2903 1.1 paulus } else if (curlen != 0) {
2904 1.1 paulus if (curlen != prevlen) {
2905 1.1 paulus send_code(s, curlen, s->bl_tree); count--;
2906 1.1 paulus }
2907 1.1 paulus Assert(count >= 3 && count <= 6, " 3_6?");
2908 1.1 paulus send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2);
2909 1.1 paulus
2910 1.1 paulus } else if (count <= 10) {
2911 1.1 paulus send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3);
2912 1.1 paulus
2913 1.1 paulus } else {
2914 1.1 paulus send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7);
2915 1.1 paulus }
2916 1.1 paulus count = 0; prevlen = curlen;
2917 1.1 paulus if (nextlen == 0) {
2918 1.1 paulus max_count = 138, min_count = 3;
2919 1.1 paulus } else if (curlen == nextlen) {
2920 1.1 paulus max_count = 6, min_count = 3;
2921 1.1 paulus } else {
2922 1.1 paulus max_count = 7, min_count = 4;
2923 1.1 paulus }
2924 1.1 paulus }
2925 1.1 paulus }
2926 1.1 paulus
2927 1.1 paulus /* ===========================================================================
2928 1.1 paulus * Construct the Huffman tree for the bit lengths and return the index in
2929 1.1 paulus * bl_order of the last bit length code to send.
2930 1.1 paulus */
2931 1.1 paulus local int build_bl_tree(s)
2932 1.1 paulus deflate_state *s;
2933 1.1 paulus {
2934 1.1 paulus int max_blindex; /* index of last bit length code of non zero freq */
2935 1.1 paulus
2936 1.1 paulus /* Determine the bit length frequencies for literal and distance trees */
2937 1.1 paulus scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code);
2938 1.1 paulus scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code);
2939 1.1 paulus
2940 1.1 paulus /* Build the bit length tree: */
2941 1.1 paulus build_tree(s, (tree_desc *)(&(s->bl_desc)));
2942 1.1 paulus /* opt_len now includes the length of the tree representations, except
2943 1.1 paulus * the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
2944 1.1 paulus */
2945 1.1 paulus
2946 1.1 paulus /* Determine the number of bit length codes to send. The pkzip format
2947 1.1 paulus * requires that at least 4 bit length codes be sent. (appnote.txt says
2948 1.1 paulus * 3 but the actual value used is 4.)
2949 1.1 paulus */
2950 1.1 paulus for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) {
2951 1.1 paulus if (s->bl_tree[bl_order[max_blindex]].Len != 0) break;
2952 1.1 paulus }
2953 1.1 paulus /* Update opt_len to include the bit length tree and counts */
2954 1.1 paulus s->opt_len += 3*(max_blindex+1) + 5+5+4;
2955 1.1 paulus Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld",
2956 1.1 paulus s->opt_len, s->static_len));
2957 1.1 paulus
2958 1.1 paulus return max_blindex;
2959 1.1 paulus }
2960 1.1 paulus
2961 1.1 paulus /* ===========================================================================
2962 1.1 paulus * Send the header for a block using dynamic Huffman trees: the counts, the
2963 1.1 paulus * lengths of the bit length codes, the literal tree and the distance tree.
2964 1.1 paulus * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
2965 1.1 paulus */
2966 1.1 paulus local void send_all_trees(s, lcodes, dcodes, blcodes)
2967 1.1 paulus deflate_state *s;
2968 1.1 paulus int lcodes, dcodes, blcodes; /* number of codes for each tree */
2969 1.1 paulus {
2970 1.1 paulus int rank; /* index in bl_order */
2971 1.1 paulus
2972 1.1 paulus Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
2973 1.1 paulus Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
2974 1.1 paulus "too many codes");
2975 1.1 paulus Tracev((stderr, "\nbl counts: "));
2976 1.1 paulus send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */
2977 1.1 paulus send_bits(s, dcodes-1, 5);
2978 1.1 paulus send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */
2979 1.1 paulus for (rank = 0; rank < blcodes; rank++) {
2980 1.1 paulus Tracev((stderr, "\nbl code %2d ", bl_order[rank]));
2981 1.1 paulus send_bits(s, s->bl_tree[bl_order[rank]].Len, 3);
2982 1.1 paulus }
2983 1.1 paulus Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent));
2984 1.1 paulus
2985 1.1 paulus send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */
2986 1.1 paulus Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent));
2987 1.1 paulus
2988 1.1 paulus send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */
2989 1.1 paulus Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent));
2990 1.1 paulus }
2991 1.1 paulus
2992 1.1 paulus /* ===========================================================================
2993 1.1 paulus * Send a stored block
2994 1.1 paulus */
2995 1.7 christos void _tr_stored_block(s, buf, stored_len, eof)
2996 1.1 paulus deflate_state *s;
2997 1.1 paulus charf *buf; /* input block */
2998 1.1 paulus ulg stored_len; /* length of input block */
2999 1.1 paulus int eof; /* true if this is the last block for a file */
3000 1.1 paulus {
3001 1.1 paulus send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */
3002 1.17 fvdl #ifdef DEBUG_ZLIB
3003 1.7 christos s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L;
3004 1.1 paulus s->compressed_len += (stored_len + 4) << 3;
3005 1.17 fvdl #endif
3006 1.1 paulus copy_block(s, buf, (unsigned)stored_len, 1); /* with header */
3007 1.1 paulus }
3008 1.1 paulus
3009 1.1 paulus /* Send just the `stored block' type code without any length bytes or data.
3010 1.1 paulus */
3011 1.7 christos void _tr_stored_type_only(s)
3012 1.1 paulus deflate_state *s;
3013 1.1 paulus {
3014 1.1 paulus send_bits(s, (STORED_BLOCK << 1), 3);
3015 1.1 paulus bi_windup(s);
3016 1.17 fvdl #ifdef DEBUG_ZLIB
3017 1.1 paulus s->compressed_len = (s->compressed_len + 3) & ~7L;
3018 1.17 fvdl #endif
3019 1.1 paulus }
3020 1.1 paulus
3021 1.1 paulus /* ===========================================================================
3022 1.1 paulus * Send one empty static block to give enough lookahead for inflate.
3023 1.1 paulus * This takes 10 bits, of which 7 may remain in the bit buffer.
3024 1.7 christos * The current inflate code requires 9 bits of lookahead. If the
3025 1.7 christos * last two codes for the previous block (real code plus EOB) were coded
3026 1.7 christos * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode
3027 1.7 christos * the last real code. In this case we send two empty static blocks instead
3028 1.7 christos * of one. (There are no problems if the previous block is stored or fixed.)
3029 1.7 christos * To simplify the code, we assume the worst case of last real code encoded
3030 1.7 christos * on one bit only.
3031 1.1 paulus */
3032 1.7 christos void _tr_align(s)
3033 1.1 paulus deflate_state *s;
3034 1.1 paulus {
3035 1.1 paulus send_bits(s, STATIC_TREES<<1, 3);
3036 1.1 paulus send_code(s, END_BLOCK, static_ltree);
3037 1.17 fvdl #ifdef DEBUG_ZLIB
3038 1.1 paulus s->compressed_len += 10L; /* 3 for block type, 7 for EOB */
3039 1.17 fvdl #endif
3040 1.1 paulus bi_flush(s);
3041 1.1 paulus /* Of the 10 bits for the empty block, we have already sent
3042 1.7 christos * (10 - bi_valid) bits. The lookahead for the last real code (before
3043 1.7 christos * the EOB of the previous block) was thus at least one plus the length
3044 1.7 christos * of the EOB plus what we have just sent of the empty static block.
3045 1.1 paulus */
3046 1.7 christos if (1 + s->last_eob_len + 10 - s->bi_valid < 9) {
3047 1.1 paulus send_bits(s, STATIC_TREES<<1, 3);
3048 1.1 paulus send_code(s, END_BLOCK, static_ltree);
3049 1.17 fvdl #ifdef DEBUG_ZLIB
3050 1.1 paulus s->compressed_len += 10L;
3051 1.17 fvdl #endif
3052 1.1 paulus bi_flush(s);
3053 1.1 paulus }
3054 1.1 paulus s->last_eob_len = 7;
3055 1.1 paulus }
3056 1.1 paulus
3057 1.1 paulus /* ===========================================================================
3058 1.1 paulus * Determine the best encoding for the current block: dynamic trees, static
3059 1.17 fvdl * trees or store, and output the encoded block to the zip file.
3060 1.1 paulus */
3061 1.17 fvdl void _tr_flush_block(s, buf, stored_len, eof)
3062 1.1 paulus deflate_state *s;
3063 1.1 paulus charf *buf; /* input block, or NULL if too old */
3064 1.1 paulus ulg stored_len; /* length of input block */
3065 1.7 christos int eof; /* true if this is the last block for a file */
3066 1.1 paulus {
3067 1.1 paulus ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
3068 1.7 christos int max_blindex = 0; /* index of last bit length code of non zero freq */
3069 1.1 paulus
3070 1.7 christos /* Build the Huffman trees unless a stored block is forced */
3071 1.7 christos if (s->level > 0) {
3072 1.1 paulus
3073 1.7 christos /* Check if the file is ascii or binary */
3074 1.7 christos if (s->data_type == Z_UNKNOWN) set_data_type(s);
3075 1.1 paulus
3076 1.7 christos /* Construct the literal and distance trees */
3077 1.7 christos build_tree(s, (tree_desc *)(&(s->l_desc)));
3078 1.7 christos Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len,
3079 1.7 christos s->static_len));
3080 1.7 christos
3081 1.7 christos build_tree(s, (tree_desc *)(&(s->d_desc)));
3082 1.7 christos Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len,
3083 1.7 christos s->static_len));
3084 1.7 christos /* At this point, opt_len and static_len are the total bit lengths of
3085 1.7 christos * the compressed block data, excluding the tree representations.
3086 1.7 christos */
3087 1.7 christos
3088 1.7 christos /* Build the bit length tree for the above two trees, and get the index
3089 1.7 christos * in bl_order of the last bit length code to send.
3090 1.7 christos */
3091 1.7 christos max_blindex = build_bl_tree(s);
3092 1.7 christos
3093 1.7 christos /* Determine the best encoding. Compute first the block length in bytes*/
3094 1.7 christos opt_lenb = (s->opt_len+3+7)>>3;
3095 1.7 christos static_lenb = (s->static_len+3+7)>>3;
3096 1.7 christos
3097 1.7 christos Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
3098 1.7 christos opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
3099 1.7 christos s->last_lit));
3100 1.1 paulus
3101 1.7 christos if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
3102 1.1 paulus
3103 1.7 christos } else {
3104 1.7 christos Assert(buf != (char*)0, "lost buf");
3105 1.7 christos opt_lenb = static_lenb = stored_len + 5; /* force a stored block */
3106 1.7 christos }
3107 1.1 paulus
3108 1.1 paulus #ifdef FORCE_STORED
3109 1.7 christos if (buf != (char*)0) { /* force stored block */
3110 1.1 paulus #else
3111 1.7 christos if (stored_len+4 <= opt_lenb && buf != (char*)0) {
3112 1.1 paulus /* 4: two words for the lengths */
3113 1.1 paulus #endif
3114 1.1 paulus /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
3115 1.1 paulus * Otherwise we can't have processed more than WSIZE input bytes since
3116 1.1 paulus * the last block flush, because compression would have been
3117 1.1 paulus * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
3118 1.1 paulus * transform a block into a stored block.
3119 1.1 paulus */
3120 1.7 christos _tr_stored_block(s, buf, stored_len, eof);
3121 1.1 paulus
3122 1.1 paulus #ifdef FORCE_STATIC
3123 1.7 christos } else if (static_lenb >= 0) { /* force static trees */
3124 1.1 paulus #else
3125 1.7 christos } else if (static_lenb == opt_lenb) {
3126 1.1 paulus #endif
3127 1.1 paulus send_bits(s, (STATIC_TREES<<1)+eof, 3);
3128 1.21 christos compress_block(s, (const ct_data *)static_ltree, (const ct_data *)static_dtree);
3129 1.17 fvdl #ifdef DEBUG_ZLIB
3130 1.1 paulus s->compressed_len += 3 + s->static_len;
3131 1.17 fvdl #endif
3132 1.1 paulus } else {
3133 1.1 paulus send_bits(s, (DYN_TREES<<1)+eof, 3);
3134 1.1 paulus send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1,
3135 1.1 paulus max_blindex+1);
3136 1.21 christos compress_block(s, (const ct_data *)s->dyn_ltree, (const ct_data *)s->dyn_dtree);
3137 1.17 fvdl #ifdef DEBUG_ZLIB
3138 1.1 paulus s->compressed_len += 3 + s->opt_len;
3139 1.17 fvdl #endif
3140 1.1 paulus }
3141 1.1 paulus Assert (s->compressed_len == s->bits_sent, "bad compressed size");
3142 1.17 fvdl /* The above check is made mod 2^32, for files larger than 512 MB
3143 1.17 fvdl * and uLong implemented on 32 bits.
3144 1.17 fvdl */
3145 1.1 paulus init_block(s);
3146 1.1 paulus
3147 1.1 paulus if (eof) {
3148 1.1 paulus bi_windup(s);
3149 1.17 fvdl #ifdef DEBUG_ZLIB
3150 1.1 paulus s->compressed_len += 7; /* align on byte boundary */
3151 1.17 fvdl #endif
3152 1.1 paulus }
3153 1.1 paulus Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3,
3154 1.1 paulus s->compressed_len-7*eof));
3155 1.1 paulus }
3156 1.1 paulus
3157 1.1 paulus /* ===========================================================================
3158 1.1 paulus * Save the match info and tally the frequency counts. Return true if
3159 1.1 paulus * the current block must be flushed.
3160 1.1 paulus */
3161 1.19 kristerw #if 0
3162 1.7 christos int _tr_tally (s, dist, lc)
3163 1.1 paulus deflate_state *s;
3164 1.7 christos unsigned dist; /* distance of matched string */
3165 1.7 christos unsigned lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */
3166 1.1 paulus {
3167 1.1 paulus s->d_buf[s->last_lit] = (ush)dist;
3168 1.1 paulus s->l_buf[s->last_lit++] = (uch)lc;
3169 1.1 paulus if (dist == 0) {
3170 1.1 paulus /* lc is the unmatched char */
3171 1.1 paulus s->dyn_ltree[lc].Freq++;
3172 1.1 paulus } else {
3173 1.1 paulus s->matches++;
3174 1.1 paulus /* Here, lc is the match length - MIN_MATCH */
3175 1.1 paulus dist--; /* dist = match distance - 1 */
3176 1.1 paulus Assert((ush)dist < (ush)MAX_DIST(s) &&
3177 1.1 paulus (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
3178 1.7 christos (ush)d_code(dist) < (ush)D_CODES, "_tr_tally: bad match");
3179 1.1 paulus
3180 1.17 fvdl s->dyn_ltree[_length_code[lc]+LITERALS+1].Freq++;
3181 1.1 paulus s->dyn_dtree[d_code(dist)].Freq++;
3182 1.1 paulus }
3183 1.1 paulus
3184 1.17 fvdl #ifdef TRUNCATE_BLOCK
3185 1.1 paulus /* Try to guess if it is profitable to stop the current block here */
3186 1.17 fvdl if ((s->last_lit & 0x1fff) == 0 && s->level > 2) {
3187 1.1 paulus /* Compute an upper bound for the compressed length */
3188 1.1 paulus ulg out_length = (ulg)s->last_lit*8L;
3189 1.7 christos ulg in_length = (ulg)((long)s->strstart - s->block_start);
3190 1.1 paulus int dcode;
3191 1.1 paulus for (dcode = 0; dcode < D_CODES; dcode++) {
3192 1.1 paulus out_length += (ulg)s->dyn_dtree[dcode].Freq *
3193 1.1 paulus (5L+extra_dbits[dcode]);
3194 1.1 paulus }
3195 1.1 paulus out_length >>= 3;
3196 1.1 paulus Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ",
3197 1.1 paulus s->last_lit, in_length, out_length,
3198 1.1 paulus 100L - out_length*100L/in_length));
3199 1.1 paulus if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1;
3200 1.1 paulus }
3201 1.17 fvdl #endif
3202 1.1 paulus return (s->last_lit == s->lit_bufsize-1);
3203 1.1 paulus /* We avoid equality with lit_bufsize because of wraparound at 64K
3204 1.1 paulus * on 16 bit machines and because stored blocks are restricted to
3205 1.1 paulus * 64K-1 bytes.
3206 1.1 paulus */
3207 1.1 paulus }
3208 1.19 kristerw #endif
3209 1.1 paulus
3210 1.1 paulus /* ===========================================================================
3211 1.1 paulus * Send the block data compressed using the given Huffman trees
3212 1.1 paulus */
3213 1.1 paulus local void compress_block(s, ltree, dtree)
3214 1.1 paulus deflate_state *s;
3215 1.21 christos const ct_data *ltree; /* literal tree */
3216 1.21 christos const ct_data *dtree; /* distance tree */
3217 1.1 paulus {
3218 1.1 paulus unsigned dist; /* distance of matched string */
3219 1.1 paulus int lc; /* match length or unmatched char (if dist == 0) */
3220 1.1 paulus unsigned lx = 0; /* running index in l_buf */
3221 1.1 paulus unsigned code; /* the code to send */
3222 1.1 paulus int extra; /* number of extra bits to send */
3223 1.1 paulus
3224 1.1 paulus if (s->last_lit != 0) do {
3225 1.1 paulus dist = s->d_buf[lx];
3226 1.1 paulus lc = s->l_buf[lx++];
3227 1.1 paulus if (dist == 0) {
3228 1.1 paulus send_code(s, lc, ltree); /* send a literal byte */
3229 1.1 paulus Tracecv(isgraph(lc), (stderr," '%c' ", lc));
3230 1.1 paulus } else {
3231 1.1 paulus /* Here, lc is the match length - MIN_MATCH */
3232 1.17 fvdl code = _length_code[lc];
3233 1.1 paulus send_code(s, code+LITERALS+1, ltree); /* send the length code */
3234 1.1 paulus extra = extra_lbits[code];
3235 1.1 paulus if (extra != 0) {
3236 1.1 paulus lc -= base_length[code];
3237 1.1 paulus send_bits(s, lc, extra); /* send the extra length bits */
3238 1.1 paulus }
3239 1.1 paulus dist--; /* dist is now the match distance - 1 */
3240 1.1 paulus code = d_code(dist);
3241 1.1 paulus Assert (code < D_CODES, "bad d_code");
3242 1.1 paulus
3243 1.1 paulus send_code(s, code, dtree); /* send the distance code */
3244 1.1 paulus extra = extra_dbits[code];
3245 1.1 paulus if (extra != 0) {
3246 1.1 paulus dist -= base_dist[code];
3247 1.1 paulus send_bits(s, dist, extra); /* send the extra distance bits */
3248 1.1 paulus }
3249 1.1 paulus } /* literal or match pair ? */
3250 1.1 paulus
3251 1.1 paulus /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */
3252 1.1 paulus Assert(s->pending < s->lit_bufsize + 2*lx, "pendingBuf overflow");
3253 1.1 paulus
3254 1.1 paulus } while (lx < s->last_lit);
3255 1.1 paulus
3256 1.1 paulus send_code(s, END_BLOCK, ltree);
3257 1.1 paulus s->last_eob_len = ltree[END_BLOCK].Len;
3258 1.1 paulus }
3259 1.1 paulus
3260 1.1 paulus /* ===========================================================================
3261 1.7 christos * Set the data type to ASCII or BINARY, using a crude approximation:
3262 1.1 paulus * binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise.
3263 1.1 paulus * IN assertion: the fields freq of dyn_ltree are set and the total of all
3264 1.1 paulus * frequencies does not exceed 64K (to fit in an int on 16 bit machines).
3265 1.1 paulus */
3266 1.1 paulus local void set_data_type(s)
3267 1.1 paulus deflate_state *s;
3268 1.1 paulus {
3269 1.1 paulus int n = 0;
3270 1.1 paulus unsigned ascii_freq = 0;
3271 1.1 paulus unsigned bin_freq = 0;
3272 1.1 paulus while (n < 7) bin_freq += s->dyn_ltree[n++].Freq;
3273 1.1 paulus while (n < 128) ascii_freq += s->dyn_ltree[n++].Freq;
3274 1.1 paulus while (n < LITERALS) bin_freq += s->dyn_ltree[n++].Freq;
3275 1.7 christos s->data_type = (Byte)(bin_freq > (ascii_freq >> 2) ? Z_BINARY : Z_ASCII);
3276 1.1 paulus }
3277 1.1 paulus
3278 1.1 paulus /* ===========================================================================
3279 1.1 paulus * Reverse the first len bits of a code, using straightforward code (a faster
3280 1.1 paulus * method would use a table)
3281 1.1 paulus * IN assertion: 1 <= len <= 15
3282 1.1 paulus */
3283 1.1 paulus local unsigned bi_reverse(code, len)
3284 1.1 paulus unsigned code; /* the value to invert */
3285 1.1 paulus int len; /* its bit length */
3286 1.1 paulus {
3287 1.10 augustss unsigned res = 0;
3288 1.1 paulus do {
3289 1.1 paulus res |= code & 1;
3290 1.1 paulus code >>= 1, res <<= 1;
3291 1.1 paulus } while (--len > 0);
3292 1.1 paulus return res >> 1;
3293 1.1 paulus }
3294 1.1 paulus
3295 1.1 paulus /* ===========================================================================
3296 1.1 paulus * Flush the bit buffer, keeping at most 7 bits in it.
3297 1.1 paulus */
3298 1.1 paulus local void bi_flush(s)
3299 1.1 paulus deflate_state *s;
3300 1.1 paulus {
3301 1.1 paulus if (s->bi_valid == 16) {
3302 1.1 paulus put_short(s, s->bi_buf);
3303 1.1 paulus s->bi_buf = 0;
3304 1.1 paulus s->bi_valid = 0;
3305 1.1 paulus } else if (s->bi_valid >= 8) {
3306 1.1 paulus put_byte(s, (Byte)s->bi_buf);
3307 1.1 paulus s->bi_buf >>= 8;
3308 1.1 paulus s->bi_valid -= 8;
3309 1.1 paulus }
3310 1.1 paulus }
3311 1.1 paulus
3312 1.1 paulus /* ===========================================================================
3313 1.1 paulus * Flush the bit buffer and align the output on a byte boundary
3314 1.1 paulus */
3315 1.1 paulus local void bi_windup(s)
3316 1.1 paulus deflate_state *s;
3317 1.1 paulus {
3318 1.1 paulus if (s->bi_valid > 8) {
3319 1.1 paulus put_short(s, s->bi_buf);
3320 1.1 paulus } else if (s->bi_valid > 0) {
3321 1.1 paulus put_byte(s, (Byte)s->bi_buf);
3322 1.1 paulus }
3323 1.1 paulus s->bi_buf = 0;
3324 1.1 paulus s->bi_valid = 0;
3325 1.1 paulus #ifdef DEBUG_ZLIB
3326 1.1 paulus s->bits_sent = (s->bits_sent+7) & ~7;
3327 1.1 paulus #endif
3328 1.1 paulus }
3329 1.1 paulus
3330 1.1 paulus /* ===========================================================================
3331 1.1 paulus * Copy a stored block, storing first the length and its
3332 1.1 paulus * one's complement if requested.
3333 1.1 paulus */
3334 1.1 paulus local void copy_block(s, buf, len, header)
3335 1.1 paulus deflate_state *s;
3336 1.1 paulus charf *buf; /* the input data */
3337 1.1 paulus unsigned len; /* its length */
3338 1.1 paulus int header; /* true if block header must be written */
3339 1.1 paulus {
3340 1.1 paulus bi_windup(s); /* align on byte boundary */
3341 1.1 paulus s->last_eob_len = 8; /* enough lookahead for inflate */
3342 1.1 paulus
3343 1.1 paulus if (header) {
3344 1.20 perry put_short(s, (ush)len);
3345 1.1 paulus put_short(s, (ush)~len);
3346 1.1 paulus #ifdef DEBUG_ZLIB
3347 1.1 paulus s->bits_sent += 2*16;
3348 1.1 paulus #endif
3349 1.1 paulus }
3350 1.1 paulus #ifdef DEBUG_ZLIB
3351 1.1 paulus s->bits_sent += (ulg)len<<3;
3352 1.1 paulus #endif
3353 1.7 christos /* bundle up the put_byte(s, *buf++) calls */
3354 1.7 christos zmemcpy(&s->pending_buf[s->pending], buf, len);
3355 1.7 christos s->pending += len;
3356 1.1 paulus }
3357 1.7 christos /* --- trees.c */
3358 1.7 christos
3359 1.7 christos /* +++ inflate.c */
3360 1.17 fvdl
3361 1.7 christos /* inflate.c -- zlib interface to inflate modules
3362 1.17 fvdl * Copyright (C) 1995-2002 Mark Adler
3363 1.20 perry * For conditions of distribution and use, see copyright notice in zlib.h
3364 1.7 christos */
3365 1.1 paulus
3366 1.7 christos /* #include "zutil.h" */
3367 1.1 paulus
3368 1.7 christos /* +++ infblock.h */
3369 1.17 fvdl
3370 1.1 paulus /* infblock.h -- header to use infblock.c
3371 1.17 fvdl * Copyright (C) 1995-2002 Mark Adler
3372 1.20 perry * For conditions of distribution and use, see copyright notice in zlib.h
3373 1.1 paulus */
3374 1.1 paulus
3375 1.1 paulus /* WARNING: this file should *not* be used by applications. It is
3376 1.1 paulus part of the implementation of the compression library and is
3377 1.1 paulus subject to change. Applications should only use zlib.h.
3378 1.1 paulus */
3379 1.1 paulus
3380 1.1 paulus struct inflate_blocks_state;
3381 1.1 paulus typedef struct inflate_blocks_state FAR inflate_blocks_statef;
3382 1.1 paulus
3383 1.17 fvdl extern inflate_blocks_statef * inflate_blocks_new __P((
3384 1.7 christos z_streamp z,
3385 1.1 paulus check_func c, /* check function */
3386 1.1 paulus uInt w)); /* window size */
3387 1.1 paulus
3388 1.17 fvdl extern int inflate_blocks __P((
3389 1.1 paulus inflate_blocks_statef *,
3390 1.7 christos z_streamp ,
3391 1.1 paulus int)); /* initial return code */
3392 1.1 paulus
3393 1.17 fvdl extern void inflate_blocks_reset __P((
3394 1.1 paulus inflate_blocks_statef *,
3395 1.7 christos z_streamp ,
3396 1.1 paulus uLongf *)); /* check value on output */
3397 1.1 paulus
3398 1.17 fvdl extern int inflate_blocks_free __P((
3399 1.1 paulus inflate_blocks_statef *,
3400 1.17 fvdl z_streamp));
3401 1.1 paulus
3402 1.17 fvdl extern void inflate_set_dictionary __P((
3403 1.7 christos inflate_blocks_statef *s,
3404 1.7 christos const Bytef *d, /* dictionary */
3405 1.7 christos uInt n)); /* dictionary length */
3406 1.7 christos
3407 1.17 fvdl extern int inflate_blocks_sync_point __P((
3408 1.17 fvdl inflate_blocks_statef *s));
3409 1.17 fvdl extern int inflate_addhistory __P((
3410 1.1 paulus inflate_blocks_statef *,
3411 1.7 christos z_streamp));
3412 1.1 paulus
3413 1.17 fvdl extern int inflate_packet_flush __P((
3414 1.1 paulus inflate_blocks_statef *));
3415 1.17 fvdl
3416 1.7 christos /* --- infblock.h */
3417 1.1 paulus
3418 1.7 christos #ifndef NO_DUMMY_DECL
3419 1.7 christos struct inflate_blocks_state {int dummy;}; /* for buggy compilers */
3420 1.1 paulus #endif
3421 1.1 paulus
3422 1.17 fvdl typedef enum {
3423 1.1 paulus METHOD, /* waiting for method byte */
3424 1.1 paulus FLAG, /* waiting for flag byte */
3425 1.7 christos DICT4, /* four dictionary check bytes to go */
3426 1.7 christos DICT3, /* three dictionary check bytes to go */
3427 1.7 christos DICT2, /* two dictionary check bytes to go */
3428 1.7 christos DICT1, /* one dictionary check byte to go */
3429 1.7 christos DICT0, /* waiting for inflateSetDictionary */
3430 1.1 paulus BLOCKS, /* decompressing blocks */
3431 1.1 paulus CHECK4, /* four check bytes to go */
3432 1.1 paulus CHECK3, /* three check bytes to go */
3433 1.1 paulus CHECK2, /* two check bytes to go */
3434 1.1 paulus CHECK1, /* one check byte to go */
3435 1.1 paulus DONE, /* finished check, done */
3436 1.1 paulus BAD} /* got an error--stay here */
3437 1.17 fvdl inflate_mode;
3438 1.17 fvdl
3439 1.17 fvdl /* inflate private state */
3440 1.17 fvdl struct internal_state {
3441 1.17 fvdl
3442 1.17 fvdl /* mode */
3443 1.17 fvdl inflate_mode mode; /* current inflate mode */
3444 1.1 paulus
3445 1.1 paulus /* mode dependent information */
3446 1.1 paulus union {
3447 1.1 paulus uInt method; /* if FLAGS, method byte */
3448 1.1 paulus struct {
3449 1.1 paulus uLong was; /* computed check value */
3450 1.1 paulus uLong need; /* stream check value */
3451 1.1 paulus } check; /* if CHECK, check values to compare */
3452 1.1 paulus uInt marker; /* if BAD, inflateSync's marker bytes count */
3453 1.1 paulus } sub; /* submode */
3454 1.1 paulus
3455 1.1 paulus /* mode independent information */
3456 1.1 paulus int nowrap; /* flag for no wrapper */
3457 1.1 paulus uInt wbits; /* log2(window size) (8..15, defaults to 15) */
3458 1.20 perry inflate_blocks_statef
3459 1.1 paulus *blocks; /* current inflate_blocks state */
3460 1.1 paulus
3461 1.1 paulus };
3462 1.1 paulus
3463 1.1 paulus
3464 1.17 fvdl int ZEXPORT inflateReset(z)
3465 1.7 christos z_streamp z;
3466 1.1 paulus {
3467 1.1 paulus if (z == Z_NULL || z->state == Z_NULL)
3468 1.1 paulus return Z_STREAM_ERROR;
3469 1.1 paulus z->total_in = z->total_out = 0;
3470 1.1 paulus z->msg = Z_NULL;
3471 1.1 paulus z->state->mode = z->state->nowrap ? BLOCKS : METHOD;
3472 1.17 fvdl inflate_blocks_reset(z->state->blocks, z, Z_NULL);
3473 1.17 fvdl Tracev((stderr, "inflate: reset\n"));
3474 1.1 paulus return Z_OK;
3475 1.1 paulus }
3476 1.1 paulus
3477 1.1 paulus
3478 1.17 fvdl int ZEXPORT inflateEnd(z)
3479 1.7 christos z_streamp z;
3480 1.1 paulus {
3481 1.1 paulus if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL)
3482 1.1 paulus return Z_STREAM_ERROR;
3483 1.1 paulus if (z->state->blocks != Z_NULL)
3484 1.17 fvdl inflate_blocks_free(z->state->blocks, z);
3485 1.7 christos ZFREE(z, z->state);
3486 1.1 paulus z->state = Z_NULL;
3487 1.17 fvdl Tracev((stderr, "inflate: end\n"));
3488 1.1 paulus return Z_OK;
3489 1.1 paulus }
3490 1.1 paulus
3491 1.1 paulus
3492 1.21 christos int ZEXPORT inflateInit2_(z, w, vers, stream_size)
3493 1.7 christos z_streamp z;
3494 1.1 paulus int w;
3495 1.21 christos const char *vers;
3496 1.7 christos int stream_size;
3497 1.1 paulus {
3498 1.21 christos if (vers == Z_NULL || vers[0] != ZLIB_VERSION[0] ||
3499 1.7 christos stream_size != sizeof(z_stream))
3500 1.7 christos return Z_VERSION_ERROR;
3501 1.7 christos
3502 1.1 paulus /* initialize state */
3503 1.1 paulus if (z == Z_NULL)
3504 1.1 paulus return Z_STREAM_ERROR;
3505 1.7 christos z->msg = Z_NULL;
3506 1.7 christos #ifndef NO_ZCFUNCS
3507 1.7 christos if (z->zalloc == Z_NULL)
3508 1.7 christos {
3509 1.7 christos z->zalloc = zcalloc;
3510 1.7 christos z->opaque = (voidpf)0;
3511 1.7 christos }
3512 1.7 christos if (z->zfree == Z_NULL) z->zfree = zcfree;
3513 1.7 christos #endif
3514 1.1 paulus if ((z->state = (struct internal_state FAR *)
3515 1.7 christos ZALLOC(z,1,sizeof(struct internal_state))) == Z_NULL)
3516 1.1 paulus return Z_MEM_ERROR;
3517 1.1 paulus z->state->blocks = Z_NULL;
3518 1.1 paulus
3519 1.1 paulus /* handle undocumented nowrap option (no zlib header or check) */
3520 1.1 paulus z->state->nowrap = 0;
3521 1.1 paulus if (w < 0)
3522 1.1 paulus {
3523 1.1 paulus w = - w;
3524 1.1 paulus z->state->nowrap = 1;
3525 1.1 paulus }
3526 1.1 paulus
3527 1.1 paulus /* set window size */
3528 1.1 paulus if (w < 8 || w > 15)
3529 1.1 paulus {
3530 1.1 paulus inflateEnd(z);
3531 1.1 paulus return Z_STREAM_ERROR;
3532 1.1 paulus }
3533 1.1 paulus z->state->wbits = (uInt)w;
3534 1.1 paulus
3535 1.1 paulus /* create inflate_blocks state */
3536 1.1 paulus if ((z->state->blocks =
3537 1.7 christos inflate_blocks_new(z, z->state->nowrap ? Z_NULL : adler32, (uInt)1 << w))
3538 1.1 paulus == Z_NULL)
3539 1.1 paulus {
3540 1.1 paulus inflateEnd(z);
3541 1.1 paulus return Z_MEM_ERROR;
3542 1.1 paulus }
3543 1.17 fvdl Tracev((stderr, "inflate: allocated\n"));
3544 1.1 paulus
3545 1.1 paulus /* reset state */
3546 1.1 paulus inflateReset(z);
3547 1.1 paulus return Z_OK;
3548 1.1 paulus }
3549 1.1 paulus
3550 1.1 paulus
3551 1.19 kristerw #if 0
3552 1.21 christos int ZEXPORT inflateInit_(z, vers, stream_size)
3553 1.7 christos z_streamp z;
3554 1.21 christos const char *vers;
3555 1.7 christos int stream_size;
3556 1.1 paulus {
3557 1.21 christos return inflateInit2_(z, DEF_WBITS, vers, stream_size);
3558 1.1 paulus }
3559 1.19 kristerw #endif
3560 1.1 paulus
3561 1.1 paulus
3562 1.1 paulus #define NEEDBYTE {if(z->avail_in==0)goto empty;r=Z_OK;}
3563 1.1 paulus #define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++)
3564 1.1 paulus
3565 1.17 fvdl int ZEXPORT inflate(z, f)
3566 1.7 christos z_streamp z;
3567 1.1 paulus int f;
3568 1.1 paulus {
3569 1.17 fvdl int r, r2;
3570 1.1 paulus uInt b;
3571 1.1 paulus
3572 1.17 fvdl if (z == Z_NULL || z->state == Z_NULL || z->next_in == Z_NULL)
3573 1.1 paulus return Z_STREAM_ERROR;
3574 1.17 fvdl r2 = f == Z_FINISH ? Z_BUF_ERROR : Z_OK;
3575 1.1 paulus r = Z_BUF_ERROR;
3576 1.1 paulus while (1) switch (z->state->mode)
3577 1.1 paulus {
3578 1.1 paulus case METHOD:
3579 1.1 paulus NEEDBYTE
3580 1.7 christos if (((z->state->sub.method = NEXTBYTE) & 0xf) != Z_DEFLATED)
3581 1.1 paulus {
3582 1.1 paulus z->state->mode = BAD;
3583 1.21 christos z->msg = "unknown compression method";
3584 1.1 paulus z->state->sub.marker = 5; /* can't try inflateSync */
3585 1.1 paulus break;
3586 1.1 paulus }
3587 1.1 paulus if ((z->state->sub.method >> 4) + 8 > z->state->wbits)
3588 1.1 paulus {
3589 1.1 paulus z->state->mode = BAD;
3590 1.21 christos z->msg = "invalid window size";
3591 1.1 paulus z->state->sub.marker = 5; /* can't try inflateSync */
3592 1.1 paulus break;
3593 1.1 paulus }
3594 1.1 paulus z->state->mode = FLAG;
3595 1.1 paulus case FLAG:
3596 1.1 paulus NEEDBYTE
3597 1.7 christos b = NEXTBYTE;
3598 1.7 christos if (((z->state->sub.method << 8) + b) % 31)
3599 1.1 paulus {
3600 1.1 paulus z->state->mode = BAD;
3601 1.21 christos z->msg = "incorrect header check";
3602 1.1 paulus z->state->sub.marker = 5; /* can't try inflateSync */
3603 1.1 paulus break;
3604 1.1 paulus }
3605 1.17 fvdl Tracev((stderr, "inflate: zlib header ok\n"));
3606 1.7 christos if (!(b & PRESET_DICT))
3607 1.1 paulus {
3608 1.7 christos z->state->mode = BLOCKS;
3609 1.17 fvdl break;
3610 1.1 paulus }
3611 1.7 christos z->state->mode = DICT4;
3612 1.7 christos case DICT4:
3613 1.7 christos NEEDBYTE
3614 1.7 christos z->state->sub.check.need = (uLong)NEXTBYTE << 24;
3615 1.7 christos z->state->mode = DICT3;
3616 1.7 christos case DICT3:
3617 1.7 christos NEEDBYTE
3618 1.7 christos z->state->sub.check.need += (uLong)NEXTBYTE << 16;
3619 1.7 christos z->state->mode = DICT2;
3620 1.7 christos case DICT2:
3621 1.7 christos NEEDBYTE
3622 1.7 christos z->state->sub.check.need += (uLong)NEXTBYTE << 8;
3623 1.7 christos z->state->mode = DICT1;
3624 1.7 christos case DICT1:
3625 1.7 christos NEEDBYTE
3626 1.7 christos z->state->sub.check.need += (uLong)NEXTBYTE;
3627 1.7 christos z->adler = z->state->sub.check.need;
3628 1.7 christos z->state->mode = DICT0;
3629 1.7 christos return Z_NEED_DICT;
3630 1.7 christos case DICT0:
3631 1.7 christos z->state->mode = BAD;
3632 1.21 christos z->msg = "need dictionary";
3633 1.7 christos z->state->sub.marker = 0; /* can try inflateSync */
3634 1.7 christos return Z_STREAM_ERROR;
3635 1.1 paulus case BLOCKS:
3636 1.1 paulus r = inflate_blocks(z->state->blocks, z, r);
3637 1.1 paulus if (f == Z_PACKET_FLUSH && z->avail_in == 0 && z->avail_out != 0)
3638 1.17 fvdl r = inflate_packet_flush(z->state->blocks);
3639 1.1 paulus if (r == Z_DATA_ERROR)
3640 1.1 paulus {
3641 1.1 paulus z->state->mode = BAD;
3642 1.1 paulus z->state->sub.marker = 0; /* can try inflateSync */
3643 1.1 paulus break;
3644 1.1 paulus }
3645 1.17 fvdl if (r == Z_OK)
3646 1.17 fvdl r = r2;
3647 1.1 paulus if (r != Z_STREAM_END)
3648 1.1 paulus return r;
3649 1.17 fvdl r = r2;
3650 1.1 paulus inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was);
3651 1.1 paulus if (z->state->nowrap)
3652 1.1 paulus {
3653 1.1 paulus z->state->mode = DONE;
3654 1.1 paulus break;
3655 1.1 paulus }
3656 1.1 paulus z->state->mode = CHECK4;
3657 1.1 paulus case CHECK4:
3658 1.1 paulus NEEDBYTE
3659 1.1 paulus z->state->sub.check.need = (uLong)NEXTBYTE << 24;
3660 1.1 paulus z->state->mode = CHECK3;
3661 1.1 paulus case CHECK3:
3662 1.1 paulus NEEDBYTE
3663 1.1 paulus z->state->sub.check.need += (uLong)NEXTBYTE << 16;
3664 1.1 paulus z->state->mode = CHECK2;
3665 1.1 paulus case CHECK2:
3666 1.1 paulus NEEDBYTE
3667 1.1 paulus z->state->sub.check.need += (uLong)NEXTBYTE << 8;
3668 1.1 paulus z->state->mode = CHECK1;
3669 1.1 paulus case CHECK1:
3670 1.1 paulus NEEDBYTE
3671 1.1 paulus z->state->sub.check.need += (uLong)NEXTBYTE;
3672 1.1 paulus
3673 1.1 paulus if (z->state->sub.check.was != z->state->sub.check.need)
3674 1.1 paulus {
3675 1.1 paulus z->state->mode = BAD;
3676 1.21 christos z->msg = "incorrect data check";
3677 1.1 paulus z->state->sub.marker = 5; /* can't try inflateSync */
3678 1.1 paulus break;
3679 1.1 paulus }
3680 1.17 fvdl Tracev((stderr, "inflate: zlib check ok\n"));
3681 1.1 paulus z->state->mode = DONE;
3682 1.1 paulus case DONE:
3683 1.1 paulus return Z_STREAM_END;
3684 1.1 paulus case BAD:
3685 1.1 paulus return Z_DATA_ERROR;
3686 1.1 paulus default:
3687 1.1 paulus return Z_STREAM_ERROR;
3688 1.1 paulus }
3689 1.1 paulus empty:
3690 1.1 paulus if (f != Z_PACKET_FLUSH)
3691 1.1 paulus return r;
3692 1.1 paulus z->state->mode = BAD;
3693 1.21 christos z->msg = "need more for packet flush";
3694 1.17 fvdl z->state->sub.marker = 0;
3695 1.1 paulus return Z_DATA_ERROR;
3696 1.1 paulus }
3697 1.1 paulus
3698 1.7 christos
3699 1.19 kristerw #if 0
3700 1.17 fvdl int ZEXPORT inflateSetDictionary(z, dictionary, dictLength)
3701 1.7 christos z_streamp z;
3702 1.7 christos const Bytef *dictionary;
3703 1.7 christos uInt dictLength;
3704 1.7 christos {
3705 1.7 christos uInt length = dictLength;
3706 1.7 christos
3707 1.7 christos if (z == Z_NULL || z->state == Z_NULL || z->state->mode != DICT0)
3708 1.7 christos return Z_STREAM_ERROR;
3709 1.7 christos
3710 1.7 christos if (adler32(1L, dictionary, dictLength) != z->adler) return Z_DATA_ERROR;
3711 1.7 christos z->adler = 1L;
3712 1.7 christos
3713 1.7 christos if (length >= ((uInt)1<<z->state->wbits))
3714 1.7 christos {
3715 1.7 christos length = (1<<z->state->wbits)-1;
3716 1.7 christos dictionary += dictLength - length;
3717 1.7 christos }
3718 1.7 christos inflate_set_dictionary(z->state->blocks, dictionary, length);
3719 1.7 christos z->state->mode = BLOCKS;
3720 1.7 christos return Z_OK;
3721 1.7 christos }
3722 1.19 kristerw #endif
3723 1.7 christos
3724 1.1 paulus /*
3725 1.1 paulus * This subroutine adds the data at next_in/avail_in to the output history
3726 1.1 paulus * without performing any output. The output buffer must be "caught up";
3727 1.1 paulus * i.e. no pending output (hence s->read equals s->write), and the state must
3728 1.1 paulus * be BLOCKS (i.e. we should be willing to see the start of a series of
3729 1.1 paulus * BLOCKS). On exit, the output will also be caught up, and the checksum
3730 1.1 paulus * will have been updated if need be.
3731 1.1 paulus */
3732 1.1 paulus
3733 1.1 paulus int inflateIncomp(z)
3734 1.1 paulus z_stream *z;
3735 1.1 paulus {
3736 1.1 paulus if (z->state->mode != BLOCKS)
3737 1.1 paulus return Z_DATA_ERROR;
3738 1.1 paulus return inflate_addhistory(z->state->blocks, z);
3739 1.1 paulus }
3740 1.1 paulus
3741 1.19 kristerw #if 0
3742 1.17 fvdl int ZEXPORT inflateSync(z)
3743 1.7 christos z_streamp z;
3744 1.1 paulus {
3745 1.1 paulus uInt n; /* number of bytes to look at */
3746 1.1 paulus Bytef *p; /* pointer to bytes */
3747 1.1 paulus uInt m; /* number of marker bytes found in a row */
3748 1.1 paulus uLong r, w; /* temporaries to save total_in and total_out */
3749 1.1 paulus
3750 1.1 paulus /* set up */
3751 1.1 paulus if (z == Z_NULL || z->state == Z_NULL)
3752 1.1 paulus return Z_STREAM_ERROR;
3753 1.1 paulus if (z->state->mode != BAD)
3754 1.1 paulus {
3755 1.1 paulus z->state->mode = BAD;
3756 1.1 paulus z->state->sub.marker = 0;
3757 1.1 paulus }
3758 1.1 paulus if ((n = z->avail_in) == 0)
3759 1.1 paulus return Z_BUF_ERROR;
3760 1.1 paulus p = z->next_in;
3761 1.1 paulus m = z->state->sub.marker;
3762 1.1 paulus
3763 1.1 paulus /* search */
3764 1.1 paulus while (n && m < 4)
3765 1.1 paulus {
3766 1.17 fvdl static const Byte mark[4] = {0, 0, 0xff, 0xff};
3767 1.17 fvdl if (*p == mark[m])
3768 1.1 paulus m++;
3769 1.1 paulus else if (*p)
3770 1.1 paulus m = 0;
3771 1.1 paulus else
3772 1.1 paulus m = 4 - m;
3773 1.1 paulus p++, n--;
3774 1.1 paulus }
3775 1.1 paulus
3776 1.1 paulus /* restore */
3777 1.1 paulus z->total_in += p - z->next_in;
3778 1.1 paulus z->next_in = p;
3779 1.1 paulus z->avail_in = n;
3780 1.1 paulus z->state->sub.marker = m;
3781 1.1 paulus
3782 1.1 paulus /* return no joy or set up to restart on a new block */
3783 1.1 paulus if (m != 4)
3784 1.1 paulus return Z_DATA_ERROR;
3785 1.1 paulus r = z->total_in; w = z->total_out;
3786 1.1 paulus inflateReset(z);
3787 1.1 paulus z->total_in = r; z->total_out = w;
3788 1.1 paulus z->state->mode = BLOCKS;
3789 1.1 paulus return Z_OK;
3790 1.1 paulus }
3791 1.19 kristerw #endif
3792 1.1 paulus
3793 1.17 fvdl
3794 1.17 fvdl /* Returns true if inflate is currently at the end of a block generated
3795 1.17 fvdl * by Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
3796 1.17 fvdl * implementation to provide an additional safety check. PPP uses Z_SYNC_FLUSH
3797 1.17 fvdl * but removes the length bytes of the resulting empty stored block. When
3798 1.17 fvdl * decompressing, PPP checks that at the end of input packet, inflate is
3799 1.17 fvdl * waiting for these length bytes.
3800 1.17 fvdl */
3801 1.19 kristerw #if 0
3802 1.17 fvdl int ZEXPORT inflateSyncPoint(z)
3803 1.17 fvdl z_streamp z;
3804 1.17 fvdl {
3805 1.17 fvdl if (z == Z_NULL || z->state == Z_NULL || z->state->blocks == Z_NULL)
3806 1.17 fvdl return Z_STREAM_ERROR;
3807 1.17 fvdl return inflate_blocks_sync_point(z->state->blocks);
3808 1.17 fvdl }
3809 1.19 kristerw #endif
3810 1.1 paulus #undef NEEDBYTE
3811 1.1 paulus #undef NEXTBYTE
3812 1.7 christos /* --- inflate.c */
3813 1.7 christos
3814 1.7 christos /* +++ infblock.c */
3815 1.17 fvdl
3816 1.7 christos /* infblock.c -- interpret and process block types to last block
3817 1.17 fvdl * Copyright (C) 1995-2002 Mark Adler
3818 1.20 perry * For conditions of distribution and use, see copyright notice in zlib.h
3819 1.7 christos */
3820 1.7 christos
3821 1.7 christos /* #include "zutil.h" */
3822 1.7 christos /* #include "infblock.h" */
3823 1.7 christos
3824 1.7 christos /* +++ inftrees.h */
3825 1.17 fvdl
3826 1.7 christos /* inftrees.h -- header to use inftrees.c
3827 1.17 fvdl * Copyright (C) 1995-2002 Mark Adler
3828 1.20 perry * For conditions of distribution and use, see copyright notice in zlib.h
3829 1.7 christos */
3830 1.7 christos
3831 1.7 christos /* WARNING: this file should *not* be used by applications. It is
3832 1.7 christos part of the implementation of the compression library and is
3833 1.7 christos subject to change. Applications should only use zlib.h.
3834 1.7 christos */
3835 1.7 christos
3836 1.7 christos /* Huffman code lookup table entry--this entry is four bytes for machines
3837 1.7 christos that have 16-bit pointers (e.g. PC's in the small or medium model). */
3838 1.7 christos
3839 1.7 christos typedef struct inflate_huft_s FAR inflate_huft;
3840 1.7 christos
3841 1.7 christos struct inflate_huft_s {
3842 1.7 christos union {
3843 1.7 christos struct {
3844 1.7 christos Byte Exop; /* number of extra bits or operation */
3845 1.7 christos Byte Bits; /* number of bits in this code or subcode */
3846 1.7 christos } what;
3847 1.17 fvdl uInt pad; /* pad structure to a power of 2 (4 bytes for */
3848 1.17 fvdl } word; /* 16-bit, 8 bytes for 32-bit int's) */
3849 1.17 fvdl uInt base; /* literal, length base, distance base,
3850 1.17 fvdl or table offset */
3851 1.7 christos };
3852 1.7 christos
3853 1.17 fvdl /* Maximum size of dynamic tree. The maximum found in a long but non-
3854 1.17 fvdl exhaustive search was 1004 huft structures (850 for length/literals
3855 1.17 fvdl and 154 for distances, the latter actually the result of an
3856 1.17 fvdl exhaustive search). The actual maximum is not known, but the
3857 1.17 fvdl value below is more than safe. */
3858 1.17 fvdl #define MANY 1440
3859 1.7 christos
3860 1.17 fvdl extern int inflate_trees_bits __P((
3861 1.7 christos uIntf *, /* 19 code lengths */
3862 1.7 christos uIntf *, /* bits tree desired/actual depth */
3863 1.7 christos inflate_huft * FAR *, /* bits tree result */
3864 1.17 fvdl inflate_huft *, /* space for trees */
3865 1.17 fvdl z_streamp)); /* for messages */
3866 1.7 christos
3867 1.17 fvdl extern int inflate_trees_dynamic __P((
3868 1.7 christos uInt, /* number of literal/length codes */
3869 1.7 christos uInt, /* number of distance codes */
3870 1.7 christos uIntf *, /* that many (total) code lengths */
3871 1.7 christos uIntf *, /* literal desired/actual bit depth */
3872 1.7 christos uIntf *, /* distance desired/actual bit depth */
3873 1.7 christos inflate_huft * FAR *, /* literal/length tree result */
3874 1.7 christos inflate_huft * FAR *, /* distance tree result */
3875 1.17 fvdl inflate_huft *, /* space for trees */
3876 1.17 fvdl z_streamp)); /* for messages */
3877 1.7 christos
3878 1.17 fvdl extern int inflate_trees_fixed __P((
3879 1.7 christos uIntf *, /* literal desired/actual bit depth */
3880 1.7 christos uIntf *, /* distance desired/actual bit depth */
3881 1.7 christos inflate_huft * FAR *, /* literal/length tree result */
3882 1.17 fvdl inflate_huft * FAR *, /* distance tree result */
3883 1.17 fvdl z_streamp)); /* for memory allocation */
3884 1.7 christos /* --- inftrees.h */
3885 1.7 christos
3886 1.7 christos /* +++ infcodes.h */
3887 1.17 fvdl
3888 1.7 christos /* infcodes.h -- header to use infcodes.c
3889 1.17 fvdl * Copyright (C) 1995-2002 Mark Adler
3890 1.20 perry * For conditions of distribution and use, see copyright notice in zlib.h
3891 1.7 christos */
3892 1.7 christos
3893 1.7 christos /* WARNING: this file should *not* be used by applications. It is
3894 1.7 christos part of the implementation of the compression library and is
3895 1.7 christos subject to change. Applications should only use zlib.h.
3896 1.7 christos */
3897 1.7 christos
3898 1.7 christos struct inflate_codes_state;
3899 1.7 christos typedef struct inflate_codes_state FAR inflate_codes_statef;
3900 1.7 christos
3901 1.17 fvdl extern inflate_codes_statef *inflate_codes_new __P((
3902 1.7 christos uInt, uInt,
3903 1.7 christos inflate_huft *, inflate_huft *,
3904 1.7 christos z_streamp ));
3905 1.7 christos
3906 1.17 fvdl extern int inflate_codes __P((
3907 1.7 christos inflate_blocks_statef *,
3908 1.7 christos z_streamp ,
3909 1.7 christos int));
3910 1.7 christos
3911 1.17 fvdl extern void inflate_codes_free __P((
3912 1.7 christos inflate_codes_statef *,
3913 1.7 christos z_streamp ));
3914 1.1 paulus
3915 1.7 christos /* --- infcodes.h */
3916 1.7 christos
3917 1.7 christos /* +++ infutil.h */
3918 1.17 fvdl
3919 1.1 paulus /* infutil.h -- types and macros common to blocks and codes
3920 1.17 fvdl * Copyright (C) 1995-2002 Mark Adler
3921 1.20 perry * For conditions of distribution and use, see copyright notice in zlib.h
3922 1.1 paulus */
3923 1.1 paulus
3924 1.1 paulus /* WARNING: this file should *not* be used by applications. It is
3925 1.1 paulus part of the implementation of the compression library and is
3926 1.1 paulus subject to change. Applications should only use zlib.h.
3927 1.1 paulus */
3928 1.1 paulus
3929 1.7 christos #ifndef _INFUTIL_H
3930 1.7 christos #define _INFUTIL_H
3931 1.1 paulus
3932 1.7 christos typedef enum {
3933 1.1 paulus TYPE, /* get type bits (3, including end bit) */
3934 1.1 paulus LENS, /* get lengths for stored */
3935 1.1 paulus STORED, /* processing stored block */
3936 1.1 paulus TABLE, /* get table lengths */
3937 1.1 paulus BTREE, /* get bit lengths tree for a dynamic block */
3938 1.1 paulus DTREE, /* get length, distance trees for a dynamic block */
3939 1.1 paulus CODES, /* processing fixed or dynamic block */
3940 1.1 paulus DRY, /* output remaining window bytes */
3941 1.7 christos DONEB, /* finished last block, done */
3942 1.7 christos BADB} /* got a data error--stuck here */
3943 1.7 christos inflate_block_mode;
3944 1.7 christos
3945 1.7 christos /* inflate blocks semi-private state */
3946 1.7 christos struct inflate_blocks_state {
3947 1.7 christos
3948 1.7 christos /* mode */
3949 1.7 christos inflate_block_mode mode; /* current inflate_block mode */
3950 1.1 paulus
3951 1.1 paulus /* mode dependent information */
3952 1.1 paulus union {
3953 1.1 paulus uInt left; /* if STORED, bytes left to copy */
3954 1.1 paulus struct {
3955 1.1 paulus uInt table; /* table lengths (14 bits) */
3956 1.1 paulus uInt index; /* index into blens (or border) */
3957 1.1 paulus uIntf *blens; /* bit lengths of codes */
3958 1.1 paulus uInt bb; /* bit length tree depth */
3959 1.1 paulus inflate_huft *tb; /* bit length decoding tree */
3960 1.1 paulus } trees; /* if DTREE, decoding info for trees */
3961 1.1 paulus struct {
3962 1.20 perry inflate_codes_statef
3963 1.1 paulus *codes;
3964 1.1 paulus } decode; /* if CODES, current state */
3965 1.1 paulus } sub; /* submode */
3966 1.1 paulus uInt last; /* true if this block is the last block */
3967 1.1 paulus
3968 1.1 paulus /* mode independent information */
3969 1.1 paulus uInt bitk; /* bits in bit buffer */
3970 1.1 paulus uLong bitb; /* bit buffer */
3971 1.17 fvdl inflate_huft *hufts; /* single malloc for tree space */
3972 1.1 paulus Bytef *window; /* sliding window */
3973 1.1 paulus Bytef *end; /* one byte after sliding window */
3974 1.1 paulus Bytef *read; /* window read pointer */
3975 1.1 paulus Bytef *write; /* window write pointer */
3976 1.1 paulus check_func checkfn; /* check function */
3977 1.1 paulus uLong check; /* check on output */
3978 1.1 paulus
3979 1.1 paulus };
3980 1.1 paulus
3981 1.1 paulus
3982 1.1 paulus /* defines for inflate input/output */
3983 1.1 paulus /* update pointers and return */
3984 1.1 paulus #define UPDBITS {s->bitb=b;s->bitk=k;}
3985 1.1 paulus #define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;}
3986 1.1 paulus #define UPDOUT {s->write=q;}
3987 1.1 paulus #define UPDATE {UPDBITS UPDIN UPDOUT}
3988 1.1 paulus #define LEAVE {UPDATE return inflate_flush(s,z,r);}
3989 1.1 paulus /* get bytes and bits */
3990 1.1 paulus #define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;}
3991 1.1 paulus #define NEEDBYTE {if(n)r=Z_OK;else LEAVE}
3992 1.1 paulus #define NEXTBYTE (n--,*p++)
3993 1.1 paulus #define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}}
3994 1.1 paulus #define DUMPBITS(j) {b>>=(j);k-=(j);}
3995 1.1 paulus /* output bytes */
3996 1.7 christos #define WAVAIL (uInt)(q<s->read?s->read-q-1:s->end-q)
3997 1.7 christos #define LOADOUT {q=s->write;m=(uInt)WAVAIL;}
3998 1.17 fvdl #define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}}
3999 1.1 paulus #define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT}
4000 1.17 fvdl #define NEEDOUT {if(m==0){WRAP if(m==0){FLUSH WRAP if(m==0) LEAVE}}r=Z_OK;}
4001 1.1 paulus #define OUTBYTE(a) {*q++=(Byte)(a);m--;}
4002 1.1 paulus /* load local pointers */
4003 1.1 paulus #define LOAD {LOADIN LOADOUT}
4004 1.1 paulus
4005 1.7 christos /* masks for lower bits (size given to avoid silly warnings with Visual C++) */
4006 1.17 fvdl extern uInt inflate_mask[17];
4007 1.1 paulus
4008 1.1 paulus /* copy as much as possible from the sliding window to the output area */
4009 1.17 fvdl extern int inflate_flush __P((
4010 1.1 paulus inflate_blocks_statef *,
4011 1.7 christos z_streamp ,
4012 1.1 paulus int));
4013 1.1 paulus
4014 1.7 christos #ifndef NO_DUMMY_DECL
4015 1.7 christos struct internal_state {int dummy;}; /* for buggy compilers */
4016 1.7 christos #endif
4017 1.1 paulus
4018 1.7 christos #endif
4019 1.7 christos /* --- infutil.h */
4020 1.1 paulus
4021 1.7 christos #ifndef NO_DUMMY_DECL
4022 1.7 christos struct inflate_codes_state {int dummy;}; /* for buggy compilers */
4023 1.7 christos #endif
4024 1.1 paulus
4025 1.17 fvdl /* simplify the use of the inflate_huft type with some defines */
4026 1.17 fvdl #define exop word.what.Exop
4027 1.17 fvdl #define bits word.what.Bits
4028 1.17 fvdl
4029 1.1 paulus /* Table for deflate from PKZIP's appnote.txt. */
4030 1.7 christos local const uInt border[] = { /* Order of the bit length code lengths */
4031 1.1 paulus 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
4032 1.1 paulus
4033 1.1 paulus /*
4034 1.1 paulus Notes beyond the 1.93a appnote.txt:
4035 1.1 paulus
4036 1.1 paulus 1. Distance pointers never point before the beginning of the output
4037 1.1 paulus stream.
4038 1.1 paulus 2. Distance pointers can point back across blocks, up to 32k away.
4039 1.1 paulus 3. There is an implied maximum of 7 bits for the bit length table and
4040 1.1 paulus 15 bits for the actual data.
4041 1.1 paulus 4. If only one code exists, then it is encoded using one bit. (Zero
4042 1.1 paulus would be more efficient, but perhaps a little confusing.) If two
4043 1.1 paulus codes exist, they are coded using one bit each (0 and 1).
4044 1.1 paulus 5. There is no way of sending zero distance codes--a dummy must be
4045 1.1 paulus sent if there are none. (History: a pre 2.0 version of PKZIP would
4046 1.1 paulus store blocks with no distance codes, but this was discovered to be
4047 1.1 paulus too harsh a criterion.) Valid only for 1.93a. 2.04c does allow
4048 1.1 paulus zero distance codes, which is sent as one code of zero bits in
4049 1.1 paulus length.
4050 1.1 paulus 6. There are up to 286 literal/length codes. Code 256 represents the
4051 1.1 paulus end-of-block. Note however that the static length tree defines
4052 1.1 paulus 288 codes just to fill out the Huffman codes. Codes 286 and 287
4053 1.1 paulus cannot be used though, since there is no length base or extra bits
4054 1.1 paulus defined for them. Similarily, there are up to 30 distance codes.
4055 1.1 paulus However, static trees define 32 codes (all 5 bits) to fill out the
4056 1.1 paulus Huffman codes, but the last two had better not show up in the data.
4057 1.1 paulus 7. Unzip can check dynamic Huffman blocks for complete code sets.
4058 1.1 paulus The exception is that a single code would not be complete (see #4).
4059 1.1 paulus 8. The five bits following the block type is really the number of
4060 1.1 paulus literal codes sent minus 257.
4061 1.1 paulus 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
4062 1.1 paulus (1+6+6). Therefore, to output three times the length, you output
4063 1.1 paulus three codes (1+1+1), whereas to output four times the same length,
4064 1.1 paulus you only need two codes (1+3). Hmm.
4065 1.1 paulus 10. In the tree reconstruction algorithm, Code = Code + Increment
4066 1.1 paulus only if BitLength(i) is not zero. (Pretty obvious.)
4067 1.1 paulus 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19)
4068 1.1 paulus 12. Note: length code 284 can represent 227-258, but length code 285
4069 1.1 paulus really is 258. The last length deserves its own, short code
4070 1.1 paulus since it gets used a lot in very redundant files. The length
4071 1.1 paulus 258 is special since 258 - 3 (the min match length) is 255.
4072 1.1 paulus 13. The literal/length and distance code bit lengths are read as a
4073 1.1 paulus single stream of lengths. It is possible (and advantageous) for
4074 1.1 paulus a repeat code (16, 17, or 18) to go across the boundary between
4075 1.1 paulus the two sets of lengths.
4076 1.1 paulus */
4077 1.1 paulus
4078 1.1 paulus
4079 1.7 christos void inflate_blocks_reset(s, z, c)
4080 1.1 paulus inflate_blocks_statef *s;
4081 1.7 christos z_streamp z;
4082 1.1 paulus uLongf *c;
4083 1.1 paulus {
4084 1.17 fvdl if (c != Z_NULL)
4085 1.1 paulus *c = s->check;
4086 1.1 paulus if (s->mode == BTREE || s->mode == DTREE)
4087 1.7 christos ZFREE(z, s->sub.trees.blens);
4088 1.1 paulus if (s->mode == CODES)
4089 1.1 paulus inflate_codes_free(s->sub.decode.codes, z);
4090 1.1 paulus s->mode = TYPE;
4091 1.1 paulus s->bitk = 0;
4092 1.1 paulus s->bitb = 0;
4093 1.1 paulus s->read = s->write = s->window;
4094 1.1 paulus if (s->checkfn != Z_NULL)
4095 1.17 fvdl z->adler = s->check = (*s->checkfn)(0L, (const Bytef *)Z_NULL, 0);
4096 1.17 fvdl Tracev((stderr, "inflate: blocks reset\n"));
4097 1.1 paulus }
4098 1.1 paulus
4099 1.1 paulus
4100 1.7 christos inflate_blocks_statef *inflate_blocks_new(z, c, w)
4101 1.7 christos z_streamp z;
4102 1.1 paulus check_func c;
4103 1.1 paulus uInt w;
4104 1.1 paulus {
4105 1.1 paulus inflate_blocks_statef *s;
4106 1.1 paulus
4107 1.7 christos if ((s = (inflate_blocks_statef *)ZALLOC
4108 1.1 paulus (z,1,sizeof(struct inflate_blocks_state))) == Z_NULL)
4109 1.1 paulus return s;
4110 1.17 fvdl if ((s->hufts =
4111 1.17 fvdl (inflate_huft *)ZALLOC(z, sizeof(inflate_huft), MANY)) == Z_NULL)
4112 1.17 fvdl {
4113 1.17 fvdl ZFREE(z, s);
4114 1.17 fvdl return Z_NULL;
4115 1.17 fvdl }
4116 1.7 christos if ((s->window = (Bytef *)ZALLOC(z, 1, w)) == Z_NULL)
4117 1.1 paulus {
4118 1.17 fvdl ZFREE(z, s->hufts);
4119 1.7 christos ZFREE(z, s);
4120 1.1 paulus return Z_NULL;
4121 1.1 paulus }
4122 1.1 paulus s->end = s->window + w;
4123 1.1 paulus s->checkfn = c;
4124 1.1 paulus s->mode = TYPE;
4125 1.17 fvdl Tracev((stderr, "inflate: blocks allocated\n"));
4126 1.17 fvdl inflate_blocks_reset(s, z, Z_NULL);
4127 1.1 paulus return s;
4128 1.1 paulus }
4129 1.1 paulus
4130 1.1 paulus
4131 1.7 christos int inflate_blocks(s, z, r)
4132 1.1 paulus inflate_blocks_statef *s;
4133 1.7 christos z_streamp z;
4134 1.1 paulus int r;
4135 1.1 paulus {
4136 1.1 paulus uInt t; /* temporary storage */
4137 1.1 paulus uLong b; /* bit buffer */
4138 1.1 paulus uInt k; /* bits in bit buffer */
4139 1.1 paulus Bytef *p; /* input data pointer */
4140 1.1 paulus uInt n; /* bytes available there */
4141 1.1 paulus Bytef *q; /* output window write pointer */
4142 1.1 paulus uInt m; /* bytes to end of window or read pointer */
4143 1.1 paulus
4144 1.1 paulus /* copy input/output information to locals (UPDATE macro restores) */
4145 1.1 paulus LOAD
4146 1.1 paulus
4147 1.1 paulus /* process input based on current state */
4148 1.1 paulus while (1) switch (s->mode)
4149 1.1 paulus {
4150 1.1 paulus case TYPE:
4151 1.1 paulus NEEDBITS(3)
4152 1.1 paulus t = (uInt)b & 7;
4153 1.1 paulus s->last = t & 1;
4154 1.1 paulus switch (t >> 1)
4155 1.1 paulus {
4156 1.1 paulus case 0: /* stored */
4157 1.17 fvdl Tracev((stderr, "inflate: stored block%s\n",
4158 1.1 paulus s->last ? " (last)" : ""));
4159 1.1 paulus DUMPBITS(3)
4160 1.1 paulus t = k & 7; /* go to byte boundary */
4161 1.1 paulus DUMPBITS(t)
4162 1.1 paulus s->mode = LENS; /* get length of stored block */
4163 1.1 paulus break;
4164 1.1 paulus case 1: /* fixed */
4165 1.17 fvdl Tracev((stderr, "inflate: fixed codes block%s\n",
4166 1.1 paulus s->last ? " (last)" : ""));
4167 1.1 paulus {
4168 1.1 paulus uInt bl, bd;
4169 1.1 paulus inflate_huft *tl, *td;
4170 1.1 paulus
4171 1.17 fvdl inflate_trees_fixed(&bl, &bd, &tl, &td, z);
4172 1.1 paulus s->sub.decode.codes = inflate_codes_new(bl, bd, tl, td, z);
4173 1.1 paulus if (s->sub.decode.codes == Z_NULL)
4174 1.1 paulus {
4175 1.1 paulus r = Z_MEM_ERROR;
4176 1.1 paulus LEAVE
4177 1.1 paulus }
4178 1.1 paulus }
4179 1.1 paulus DUMPBITS(3)
4180 1.1 paulus s->mode = CODES;
4181 1.1 paulus break;
4182 1.1 paulus case 2: /* dynamic */
4183 1.17 fvdl Tracev((stderr, "inflate: dynamic codes block%s\n",
4184 1.1 paulus s->last ? " (last)" : ""));
4185 1.1 paulus DUMPBITS(3)
4186 1.1 paulus s->mode = TABLE;
4187 1.1 paulus break;
4188 1.1 paulus case 3: /* illegal */
4189 1.1 paulus DUMPBITS(3)
4190 1.1 paulus s->mode = BADB;
4191 1.21 christos z->msg = "invalid block type";
4192 1.1 paulus r = Z_DATA_ERROR;
4193 1.1 paulus LEAVE
4194 1.1 paulus }
4195 1.1 paulus break;
4196 1.1 paulus case LENS:
4197 1.1 paulus NEEDBITS(32)
4198 1.7 christos if ((((~b) >> 16) & 0xffff) != (b & 0xffff))
4199 1.1 paulus {
4200 1.1 paulus s->mode = BADB;
4201 1.21 christos z->msg = "invalid stored block lengths";
4202 1.1 paulus r = Z_DATA_ERROR;
4203 1.1 paulus LEAVE
4204 1.1 paulus }
4205 1.1 paulus s->sub.left = (uInt)b & 0xffff;
4206 1.1 paulus b = k = 0; /* dump bits */
4207 1.1 paulus Tracev((stderr, "inflate: stored length %u\n", s->sub.left));
4208 1.7 christos s->mode = s->sub.left ? STORED : (s->last ? DRY : TYPE);
4209 1.1 paulus break;
4210 1.1 paulus case STORED:
4211 1.1 paulus if (n == 0)
4212 1.1 paulus LEAVE
4213 1.1 paulus NEEDOUT
4214 1.1 paulus t = s->sub.left;
4215 1.1 paulus if (t > n) t = n;
4216 1.1 paulus if (t > m) t = m;
4217 1.1 paulus zmemcpy(q, p, t);
4218 1.1 paulus p += t; n -= t;
4219 1.1 paulus q += t; m -= t;
4220 1.1 paulus if ((s->sub.left -= t) != 0)
4221 1.1 paulus break;
4222 1.1 paulus Tracev((stderr, "inflate: stored end, %lu total out\n",
4223 1.1 paulus z->total_out + (q >= s->read ? q - s->read :
4224 1.1 paulus (s->end - s->read) + (q - s->window))));
4225 1.1 paulus s->mode = s->last ? DRY : TYPE;
4226 1.1 paulus break;
4227 1.1 paulus case TABLE:
4228 1.1 paulus NEEDBITS(14)
4229 1.1 paulus s->sub.trees.table = t = (uInt)b & 0x3fff;
4230 1.1 paulus #ifndef PKZIP_BUG_WORKAROUND
4231 1.1 paulus if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29)
4232 1.1 paulus {
4233 1.1 paulus s->mode = BADB;
4234 1.21 christos z->msg = "too many length or distance symbols";
4235 1.1 paulus r = Z_DATA_ERROR;
4236 1.1 paulus LEAVE
4237 1.1 paulus }
4238 1.1 paulus #endif
4239 1.1 paulus t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
4240 1.1 paulus if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL)
4241 1.1 paulus {
4242 1.1 paulus r = Z_MEM_ERROR;
4243 1.1 paulus LEAVE
4244 1.1 paulus }
4245 1.1 paulus DUMPBITS(14)
4246 1.1 paulus s->sub.trees.index = 0;
4247 1.1 paulus Tracev((stderr, "inflate: table sizes ok\n"));
4248 1.1 paulus s->mode = BTREE;
4249 1.1 paulus case BTREE:
4250 1.1 paulus while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10))
4251 1.1 paulus {
4252 1.1 paulus NEEDBITS(3)
4253 1.1 paulus s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7;
4254 1.1 paulus DUMPBITS(3)
4255 1.1 paulus }
4256 1.1 paulus while (s->sub.trees.index < 19)
4257 1.1 paulus s->sub.trees.blens[border[s->sub.trees.index++]] = 0;
4258 1.1 paulus s->sub.trees.bb = 7;
4259 1.1 paulus t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb,
4260 1.17 fvdl &s->sub.trees.tb, s->hufts, z);
4261 1.1 paulus if (t != Z_OK)
4262 1.1 paulus {
4263 1.1 paulus r = t;
4264 1.1 paulus if (r == Z_DATA_ERROR)
4265 1.17 fvdl {
4266 1.17 fvdl ZFREE(z, s->sub.trees.blens);
4267 1.1 paulus s->mode = BADB;
4268 1.17 fvdl }
4269 1.1 paulus LEAVE
4270 1.1 paulus }
4271 1.1 paulus s->sub.trees.index = 0;
4272 1.1 paulus Tracev((stderr, "inflate: bits tree ok\n"));
4273 1.1 paulus s->mode = DTREE;
4274 1.1 paulus case DTREE:
4275 1.1 paulus while (t = s->sub.trees.table,
4276 1.1 paulus s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f))
4277 1.1 paulus {
4278 1.1 paulus inflate_huft *h;
4279 1.1 paulus uInt i, j, c;
4280 1.1 paulus
4281 1.1 paulus t = s->sub.trees.bb;
4282 1.1 paulus NEEDBITS(t)
4283 1.1 paulus h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]);
4284 1.17 fvdl t = h->bits;
4285 1.17 fvdl c = h->base;
4286 1.1 paulus if (c < 16)
4287 1.1 paulus {
4288 1.1 paulus DUMPBITS(t)
4289 1.1 paulus s->sub.trees.blens[s->sub.trees.index++] = c;
4290 1.1 paulus }
4291 1.1 paulus else /* c == 16..18 */
4292 1.1 paulus {
4293 1.1 paulus i = c == 18 ? 7 : c - 14;
4294 1.1 paulus j = c == 18 ? 11 : 3;
4295 1.1 paulus NEEDBITS(t + i)
4296 1.1 paulus DUMPBITS(t)
4297 1.1 paulus j += (uInt)b & inflate_mask[i];
4298 1.1 paulus DUMPBITS(i)
4299 1.1 paulus i = s->sub.trees.index;
4300 1.1 paulus t = s->sub.trees.table;
4301 1.1 paulus if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) ||
4302 1.1 paulus (c == 16 && i < 1))
4303 1.1 paulus {
4304 1.7 christos ZFREE(z, s->sub.trees.blens);
4305 1.1 paulus s->mode = BADB;
4306 1.21 christos z->msg = "invalid bit length repeat";
4307 1.1 paulus r = Z_DATA_ERROR;
4308 1.1 paulus LEAVE
4309 1.1 paulus }
4310 1.1 paulus c = c == 16 ? s->sub.trees.blens[i - 1] : 0;
4311 1.1 paulus do {
4312 1.1 paulus s->sub.trees.blens[i++] = c;
4313 1.1 paulus } while (--j);
4314 1.1 paulus s->sub.trees.index = i;
4315 1.1 paulus }
4316 1.1 paulus }
4317 1.1 paulus s->sub.trees.tb = Z_NULL;
4318 1.1 paulus {
4319 1.1 paulus uInt bl, bd;
4320 1.1 paulus inflate_huft *tl, *td;
4321 1.1 paulus inflate_codes_statef *c;
4322 1.1 paulus
4323 1.1 paulus bl = 9; /* must be <= 9 for lookahead assumptions */
4324 1.1 paulus bd = 6; /* must be <= 9 for lookahead assumptions */
4325 1.1 paulus t = s->sub.trees.table;
4326 1.1 paulus t = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f),
4327 1.17 fvdl s->sub.trees.blens, &bl, &bd, &tl, &td,
4328 1.17 fvdl s->hufts, z);
4329 1.1 paulus if (t != Z_OK)
4330 1.1 paulus {
4331 1.1 paulus if (t == (uInt)Z_DATA_ERROR)
4332 1.17 fvdl {
4333 1.17 fvdl ZFREE(z, s->sub.trees.blens);
4334 1.1 paulus s->mode = BADB;
4335 1.17 fvdl }
4336 1.1 paulus r = t;
4337 1.1 paulus LEAVE
4338 1.1 paulus }
4339 1.17 fvdl Tracev((stderr, "inflate: trees ok\n"));
4340 1.1 paulus if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL)
4341 1.1 paulus {
4342 1.1 paulus r = Z_MEM_ERROR;
4343 1.1 paulus LEAVE
4344 1.1 paulus }
4345 1.1 paulus s->sub.decode.codes = c;
4346 1.1 paulus }
4347 1.17 fvdl ZFREE(z, s->sub.trees.blens);
4348 1.1 paulus s->mode = CODES;
4349 1.1 paulus case CODES:
4350 1.1 paulus UPDATE
4351 1.1 paulus if ((r = inflate_codes(s, z, r)) != Z_STREAM_END)
4352 1.1 paulus return inflate_flush(s, z, r);
4353 1.1 paulus r = Z_OK;
4354 1.1 paulus inflate_codes_free(s->sub.decode.codes, z);
4355 1.1 paulus LOAD
4356 1.1 paulus Tracev((stderr, "inflate: codes end, %lu total out\n",
4357 1.1 paulus z->total_out + (q >= s->read ? q - s->read :
4358 1.1 paulus (s->end - s->read) + (q - s->window))));
4359 1.1 paulus if (!s->last)
4360 1.1 paulus {
4361 1.1 paulus s->mode = TYPE;
4362 1.1 paulus break;
4363 1.1 paulus }
4364 1.1 paulus s->mode = DRY;
4365 1.1 paulus case DRY:
4366 1.1 paulus FLUSH
4367 1.1 paulus if (s->read != s->write)
4368 1.1 paulus LEAVE
4369 1.1 paulus s->mode = DONEB;
4370 1.1 paulus case DONEB:
4371 1.1 paulus r = Z_STREAM_END;
4372 1.1 paulus LEAVE
4373 1.1 paulus case BADB:
4374 1.1 paulus r = Z_DATA_ERROR;
4375 1.1 paulus LEAVE
4376 1.1 paulus default:
4377 1.1 paulus r = Z_STREAM_ERROR;
4378 1.1 paulus LEAVE
4379 1.1 paulus }
4380 1.1 paulus }
4381 1.1 paulus
4382 1.1 paulus
4383 1.17 fvdl int inflate_blocks_free(s, z)
4384 1.1 paulus inflate_blocks_statef *s;
4385 1.7 christos z_streamp z;
4386 1.1 paulus {
4387 1.17 fvdl inflate_blocks_reset(s, z, Z_NULL);
4388 1.7 christos ZFREE(z, s->window);
4389 1.17 fvdl ZFREE(z, s->hufts);
4390 1.7 christos ZFREE(z, s);
4391 1.17 fvdl Tracev((stderr, "inflate: blocks freed\n"));
4392 1.1 paulus return Z_OK;
4393 1.1 paulus }
4394 1.1 paulus
4395 1.7 christos
4396 1.19 kristerw #if 0
4397 1.7 christos void inflate_set_dictionary(s, d, n)
4398 1.7 christos inflate_blocks_statef *s;
4399 1.7 christos const Bytef *d;
4400 1.7 christos uInt n;
4401 1.7 christos {
4402 1.17 fvdl zmemcpy(s->window, d, n);
4403 1.7 christos s->read = s->write = s->window + n;
4404 1.7 christos }
4405 1.19 kristerw #endif
4406 1.7 christos
4407 1.1 paulus /*
4408 1.1 paulus * This subroutine adds the data at next_in/avail_in to the output history
4409 1.1 paulus * without performing any output. The output buffer must be "caught up";
4410 1.1 paulus * i.e. no pending output (hence s->read equals s->write), and the state must
4411 1.1 paulus * be BLOCKS (i.e. we should be willing to see the start of a series of
4412 1.1 paulus * BLOCKS). On exit, the output will also be caught up, and the checksum
4413 1.1 paulus * will have been updated if need be.
4414 1.1 paulus */
4415 1.7 christos int inflate_addhistory(s, z)
4416 1.1 paulus inflate_blocks_statef *s;
4417 1.1 paulus z_stream *z;
4418 1.1 paulus {
4419 1.1 paulus uLong b; /* bit buffer */ /* NOT USED HERE */
4420 1.1 paulus uInt k; /* bits in bit buffer */ /* NOT USED HERE */
4421 1.1 paulus uInt t; /* temporary storage */
4422 1.1 paulus Bytef *p; /* input data pointer */
4423 1.1 paulus uInt n; /* bytes available there */
4424 1.1 paulus Bytef *q; /* output window write pointer */
4425 1.1 paulus uInt m; /* bytes to end of window or read pointer */
4426 1.1 paulus
4427 1.1 paulus if (s->read != s->write)
4428 1.1 paulus return Z_STREAM_ERROR;
4429 1.1 paulus if (s->mode != TYPE)
4430 1.1 paulus return Z_DATA_ERROR;
4431 1.1 paulus
4432 1.1 paulus /* we're ready to rock */
4433 1.1 paulus LOAD
4434 1.1 paulus /* while there is input ready, copy to output buffer, moving
4435 1.1 paulus * pointers as needed.
4436 1.1 paulus */
4437 1.1 paulus while (n) {
4438 1.1 paulus t = n; /* how many to do */
4439 1.1 paulus /* is there room until end of buffer? */
4440 1.1 paulus if (t > m) t = m;
4441 1.1 paulus /* update check information */
4442 1.1 paulus if (s->checkfn != Z_NULL)
4443 1.1 paulus s->check = (*s->checkfn)(s->check, q, t);
4444 1.1 paulus zmemcpy(q, p, t);
4445 1.1 paulus q += t;
4446 1.1 paulus p += t;
4447 1.1 paulus n -= t;
4448 1.1 paulus z->total_out += t;
4449 1.1 paulus s->read = q; /* drag read pointer forward */
4450 1.7 christos /* WWRAP */ /* expand WWRAP macro by hand to handle s->read */
4451 1.1 paulus if (q == s->end) {
4452 1.1 paulus s->read = q = s->window;
4453 1.1 paulus m = WAVAIL;
4454 1.1 paulus }
4455 1.1 paulus }
4456 1.1 paulus UPDATE
4457 1.1 paulus return Z_OK;
4458 1.1 paulus }
4459 1.1 paulus
4460 1.1 paulus
4461 1.1 paulus /*
4462 1.1 paulus * At the end of a Deflate-compressed PPP packet, we expect to have seen
4463 1.1 paulus * a `stored' block type value but not the (zero) length bytes.
4464 1.1 paulus */
4465 1.7 christos int inflate_packet_flush(s)
4466 1.1 paulus inflate_blocks_statef *s;
4467 1.1 paulus {
4468 1.1 paulus if (s->mode != LENS)
4469 1.1 paulus return Z_DATA_ERROR;
4470 1.1 paulus s->mode = TYPE;
4471 1.1 paulus return Z_OK;
4472 1.1 paulus }
4473 1.17 fvdl
4474 1.17 fvdl /* Returns true if inflate is currently at the end of a block generated
4475 1.20 perry * by Z_SYNC_FLUSH or Z_FULL_FLUSH.
4476 1.17 fvdl * IN assertion: s != Z_NULL
4477 1.17 fvdl */
4478 1.19 kristerw #if 0
4479 1.17 fvdl int inflate_blocks_sync_point(s)
4480 1.17 fvdl inflate_blocks_statef *s;
4481 1.17 fvdl {
4482 1.17 fvdl return s->mode == LENS;
4483 1.17 fvdl }
4484 1.19 kristerw #endif
4485 1.7 christos /* --- infblock.c */
4486 1.1 paulus
4487 1.17 fvdl
4488 1.7 christos /* +++ inftrees.c */
4489 1.17 fvdl
4490 1.1 paulus /* inftrees.c -- generate Huffman trees for efficient decoding
4491 1.17 fvdl * Copyright (C) 1995-2002 Mark Adler
4492 1.20 perry * For conditions of distribution and use, see copyright notice in zlib.h
4493 1.1 paulus */
4494 1.1 paulus
4495 1.7 christos /* #include "zutil.h" */
4496 1.7 christos /* #include "inftrees.h" */
4497 1.7 christos
4498 1.17 fvdl #if !defined(BUILDFIXED) && !defined(STDC)
4499 1.17 fvdl # define BUILDFIXED /* non ANSI compilers may not accept inffixed.h */
4500 1.17 fvdl #endif
4501 1.17 fvdl
4502 1.17 fvdl const char inflate_copyright[] =
4503 1.17 fvdl " inflate 1.1.4 Copyright 1995-2002 Mark Adler ";
4504 1.7 christos /*
4505 1.7 christos If you use the zlib library in a product, an acknowledgment is welcome
4506 1.7 christos in the documentation of your product. If for some reason you cannot
4507 1.7 christos include such an acknowledgment, I would appreciate that you keep this
4508 1.7 christos copyright string in the executable of your product.
4509 1.7 christos */
4510 1.7 christos
4511 1.7 christos #ifndef NO_DUMMY_DECL
4512 1.7 christos struct internal_state {int dummy;}; /* for buggy compilers */
4513 1.7 christos #endif
4514 1.7 christos
4515 1.1 paulus /* simplify the use of the inflate_huft type with some defines */
4516 1.1 paulus #define exop word.what.Exop
4517 1.1 paulus #define bits word.what.Bits
4518 1.1 paulus
4519 1.1 paulus
4520 1.17 fvdl local int huft_build __P((
4521 1.1 paulus uIntf *, /* code lengths in bits */
4522 1.1 paulus uInt, /* number of codes */
4523 1.1 paulus uInt, /* number of "simple" codes */
4524 1.7 christos const uIntf *, /* list of base values for non-simple codes */
4525 1.7 christos const uIntf *, /* list of extra bits for non-simple codes */
4526 1.1 paulus inflate_huft * FAR*,/* result: starting table */
4527 1.1 paulus uIntf *, /* maximum lookup bits (returns actual) */
4528 1.17 fvdl inflate_huft *, /* space for trees */
4529 1.17 fvdl uInt *, /* hufts used in space */
4530 1.17 fvdl uIntf * )); /* space for values */
4531 1.1 paulus
4532 1.1 paulus /* Tables for deflate from PKZIP's appnote.txt. */
4533 1.7 christos local const uInt cplens[31] = { /* Copy lengths for literal codes 257..285 */
4534 1.1 paulus 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
4535 1.1 paulus 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
4536 1.7 christos /* see note #13 above about 258 */
4537 1.7 christos local const uInt cplext[31] = { /* Extra bits for literal codes 257..285 */
4538 1.1 paulus 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
4539 1.7 christos 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 112, 112}; /* 112==invalid */
4540 1.7 christos local const uInt cpdist[30] = { /* Copy offsets for distance codes 0..29 */
4541 1.1 paulus 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
4542 1.1 paulus 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
4543 1.1 paulus 8193, 12289, 16385, 24577};
4544 1.7 christos local const uInt cpdext[30] = { /* Extra bits for distance codes */
4545 1.1 paulus 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
4546 1.1 paulus 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
4547 1.1 paulus 12, 12, 13, 13};
4548 1.1 paulus
4549 1.1 paulus /*
4550 1.1 paulus Huffman code decoding is performed using a multi-level table lookup.
4551 1.1 paulus The fastest way to decode is to simply build a lookup table whose
4552 1.1 paulus size is determined by the longest code. However, the time it takes
4553 1.1 paulus to build this table can also be a factor if the data being decoded
4554 1.1 paulus is not very long. The most common codes are necessarily the
4555 1.1 paulus shortest codes, so those codes dominate the decoding time, and hence
4556 1.1 paulus the speed. The idea is you can have a shorter table that decodes the
4557 1.1 paulus shorter, more probable codes, and then point to subsidiary tables for
4558 1.1 paulus the longer codes. The time it costs to decode the longer codes is
4559 1.1 paulus then traded against the time it takes to make longer tables.
4560 1.1 paulus
4561 1.1 paulus This results of this trade are in the variables lbits and dbits
4562 1.1 paulus below. lbits is the number of bits the first level table for literal/
4563 1.1 paulus length codes can decode in one step, and dbits is the same thing for
4564 1.1 paulus the distance codes. Subsequent tables are also less than or equal to
4565 1.1 paulus those sizes. These values may be adjusted either when all of the
4566 1.1 paulus codes are shorter than that, in which case the longest code length in
4567 1.1 paulus bits is used, or when the shortest code is *longer* than the requested
4568 1.1 paulus table size, in which case the length of the shortest code in bits is
4569 1.1 paulus used.
4570 1.1 paulus
4571 1.1 paulus There are two different values for the two tables, since they code a
4572 1.1 paulus different number of possibilities each. The literal/length table
4573 1.1 paulus codes 286 possible values, or in a flat code, a little over eight
4574 1.1 paulus bits. The distance table codes 30 possible values, or a little less
4575 1.1 paulus than five bits, flat. The optimum values for speed end up being
4576 1.1 paulus about one bit more than those, so lbits is 8+1 and dbits is 5+1.
4577 1.1 paulus The optimum values may differ though from machine to machine, and
4578 1.1 paulus possibly even between compilers. Your mileage may vary.
4579 1.1 paulus */
4580 1.1 paulus
4581 1.1 paulus
4582 1.1 paulus /* If BMAX needs to be larger than 16, then h and x[] should be uLong. */
4583 1.1 paulus #define BMAX 15 /* maximum bit length of any code */
4584 1.1 paulus
4585 1.17 fvdl local int huft_build(b, n, s, d, e, t, m, hp, hn, v)
4586 1.1 paulus uIntf *b; /* code lengths in bits (all assumed <= BMAX) */
4587 1.17 fvdl uInt n; /* number of codes (assumed <= 288) */
4588 1.1 paulus uInt s; /* number of simple-valued codes (0..s-1) */
4589 1.7 christos const uIntf *d; /* list of base values for non-simple codes */
4590 1.7 christos const uIntf *e; /* list of extra bits for non-simple codes */
4591 1.1 paulus inflate_huft * FAR *t; /* result: starting table */
4592 1.1 paulus uIntf *m; /* maximum lookup bits, returns actual */
4593 1.17 fvdl inflate_huft *hp; /* space for trees */
4594 1.17 fvdl uInt *hn; /* hufts used in space */
4595 1.17 fvdl uIntf *v; /* working area: values in order of bit length */
4596 1.1 paulus /* Given a list of code lengths and a maximum table size, make a set of
4597 1.1 paulus tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR
4598 1.1 paulus if the given code set is incomplete (the tables are still built in this
4599 1.17 fvdl case), or Z_DATA_ERROR if the input is invalid. */
4600 1.1 paulus {
4601 1.1 paulus
4602 1.1 paulus uInt a; /* counter for codes of length k */
4603 1.1 paulus uInt c[BMAX+1]; /* bit length count table */
4604 1.1 paulus uInt f; /* i repeats in table every f entries */
4605 1.1 paulus int g; /* maximum code length */
4606 1.1 paulus int h; /* table level */
4607 1.17 fvdl uInt i; /* counter, current code */
4608 1.17 fvdl uInt j; /* counter */
4609 1.17 fvdl int k; /* number of bits in current code */
4610 1.1 paulus int l; /* bits per table (returned in m) */
4611 1.17 fvdl uInt mask; /* (1 << w) - 1, to avoid cc -O bug on HP */
4612 1.17 fvdl uIntf *p; /* pointer into c[], b[], or v[] */
4613 1.1 paulus inflate_huft *q; /* points to current table */
4614 1.1 paulus struct inflate_huft_s r; /* table entry for structure assignment */
4615 1.1 paulus inflate_huft *u[BMAX]; /* table stack */
4616 1.17 fvdl int w; /* bits before this table == (l * h) */
4617 1.1 paulus uInt x[BMAX+1]; /* bit offsets, then code stack */
4618 1.1 paulus uIntf *xp; /* pointer into x */
4619 1.1 paulus int y; /* number of dummy codes added */
4620 1.1 paulus uInt z; /* number of entries in current table */
4621 1.1 paulus
4622 1.26 mrg r.base = 0; /* XXX gcc */
4623 1.1 paulus
4624 1.1 paulus /* Generate counts for each bit length */
4625 1.1 paulus p = c;
4626 1.1 paulus #define C0 *p++ = 0;
4627 1.1 paulus #define C2 C0 C0 C0 C0
4628 1.1 paulus #define C4 C2 C2 C2 C2
4629 1.1 paulus C4 /* clear c[]--assume BMAX+1 is 16 */
4630 1.1 paulus p = b; i = n;
4631 1.1 paulus do {
4632 1.1 paulus c[*p++]++; /* assume all entries <= BMAX */
4633 1.1 paulus } while (--i);
4634 1.1 paulus if (c[0] == n) /* null input--all zero length codes */
4635 1.1 paulus {
4636 1.1 paulus *t = (inflate_huft *)Z_NULL;
4637 1.1 paulus *m = 0;
4638 1.1 paulus return Z_OK;
4639 1.1 paulus }
4640 1.1 paulus
4641 1.1 paulus
4642 1.1 paulus /* Find minimum and maximum length, bound *m by those */
4643 1.1 paulus l = *m;
4644 1.1 paulus for (j = 1; j <= BMAX; j++)
4645 1.1 paulus if (c[j])
4646 1.1 paulus break;
4647 1.1 paulus k = j; /* minimum code length */
4648 1.1 paulus if ((uInt)l < j)
4649 1.1 paulus l = j;
4650 1.1 paulus for (i = BMAX; i; i--)
4651 1.1 paulus if (c[i])
4652 1.1 paulus break;
4653 1.1 paulus g = i; /* maximum code length */
4654 1.1 paulus if ((uInt)l > i)
4655 1.1 paulus l = i;
4656 1.1 paulus *m = l;
4657 1.1 paulus
4658 1.1 paulus
4659 1.1 paulus /* Adjust last length count to fill out codes, if needed */
4660 1.1 paulus for (y = 1 << j; j < i; j++, y <<= 1)
4661 1.1 paulus if ((y -= c[j]) < 0)
4662 1.1 paulus return Z_DATA_ERROR;
4663 1.1 paulus if ((y -= c[i]) < 0)
4664 1.1 paulus return Z_DATA_ERROR;
4665 1.1 paulus c[i] += y;
4666 1.1 paulus
4667 1.1 paulus
4668 1.1 paulus /* Generate starting offsets into the value table for each length */
4669 1.1 paulus x[1] = j = 0;
4670 1.1 paulus p = c + 1; xp = x + 2;
4671 1.1 paulus while (--i) { /* note that i == g from above */
4672 1.1 paulus *xp++ = (j += *p++);
4673 1.1 paulus }
4674 1.1 paulus
4675 1.1 paulus
4676 1.1 paulus /* Make a table of values in order of bit lengths */
4677 1.1 paulus p = b; i = 0;
4678 1.1 paulus do {
4679 1.1 paulus if ((j = *p++) != 0)
4680 1.1 paulus v[x[j]++] = i;
4681 1.1 paulus } while (++i < n);
4682 1.17 fvdl n = x[g]; /* set n to length of v */
4683 1.1 paulus
4684 1.1 paulus
4685 1.1 paulus /* Generate the Huffman codes and for each, make the table entries */
4686 1.1 paulus x[0] = i = 0; /* first Huffman code is zero */
4687 1.1 paulus p = v; /* grab values in bit order */
4688 1.1 paulus h = -1; /* no tables yet--level -1 */
4689 1.1 paulus w = -l; /* bits decoded == (l * h) */
4690 1.1 paulus u[0] = (inflate_huft *)Z_NULL; /* just to keep compilers happy */
4691 1.1 paulus q = (inflate_huft *)Z_NULL; /* ditto */
4692 1.1 paulus z = 0; /* ditto */
4693 1.1 paulus
4694 1.1 paulus /* go through the bit lengths (k already is bits in shortest code) */
4695 1.1 paulus for (; k <= g; k++)
4696 1.1 paulus {
4697 1.1 paulus a = c[k];
4698 1.1 paulus while (a--)
4699 1.1 paulus {
4700 1.1 paulus /* here i is the Huffman code of length k bits for value *p */
4701 1.1 paulus /* make tables up to required level */
4702 1.1 paulus while (k > w + l)
4703 1.1 paulus {
4704 1.1 paulus h++;
4705 1.1 paulus w += l; /* previous table always l bits */
4706 1.1 paulus
4707 1.1 paulus /* compute minimum size table less than or equal to l bits */
4708 1.7 christos z = g - w;
4709 1.7 christos z = z > (uInt)l ? l : z; /* table size upper limit */
4710 1.1 paulus if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */
4711 1.1 paulus { /* too few codes for k-w bit table */
4712 1.1 paulus f -= a + 1; /* deduct codes from patterns left */
4713 1.1 paulus xp = c + k;
4714 1.1 paulus if (j < z)
4715 1.1 paulus while (++j < z) /* try smaller tables up to z bits */
4716 1.1 paulus {
4717 1.1 paulus if ((f <<= 1) <= *++xp)
4718 1.1 paulus break; /* enough codes to use up j bits */
4719 1.1 paulus f -= *xp; /* else deduct codes from patterns */
4720 1.1 paulus }
4721 1.1 paulus }
4722 1.1 paulus z = 1 << j; /* table entries for j-bit table */
4723 1.1 paulus
4724 1.17 fvdl /* allocate new table */
4725 1.17 fvdl if (*hn + z > MANY) /* (note: doesn't matter for fixed) */
4726 1.17 fvdl return Z_DATA_ERROR; /* overflow of MANY */
4727 1.17 fvdl u[h] = q = hp + *hn;
4728 1.17 fvdl *hn += z;
4729 1.1 paulus
4730 1.1 paulus /* connect to last table, if there is one */
4731 1.1 paulus if (h)
4732 1.1 paulus {
4733 1.1 paulus x[h] = i; /* save pattern for backing up */
4734 1.1 paulus r.bits = (Byte)l; /* bits to dump before this table */
4735 1.1 paulus r.exop = (Byte)j; /* bits in this table */
4736 1.17 fvdl j = i >> (w - l);
4737 1.17 fvdl r.base = (uInt)(q - u[h-1] - j); /* offset to this table */
4738 1.1 paulus u[h-1][j] = r; /* connect to last table */
4739 1.1 paulus }
4740 1.17 fvdl else
4741 1.17 fvdl *t = q; /* first table is returned result */
4742 1.1 paulus }
4743 1.1 paulus
4744 1.1 paulus /* set up table entry in r */
4745 1.1 paulus r.bits = (Byte)(k - w);
4746 1.1 paulus if (p >= v + n)
4747 1.1 paulus r.exop = 128 + 64; /* out of values--invalid code */
4748 1.1 paulus else if (*p < s)
4749 1.1 paulus {
4750 1.1 paulus r.exop = (Byte)(*p < 256 ? 0 : 32 + 64); /* 256 is end-of-block */
4751 1.1 paulus r.base = *p++; /* simple code is just the value */
4752 1.1 paulus }
4753 1.1 paulus else
4754 1.1 paulus {
4755 1.7 christos r.exop = (Byte)(e[*p - s] + 16 + 64);/* non-simple--look up in lists */
4756 1.1 paulus r.base = d[*p++ - s];
4757 1.1 paulus }
4758 1.1 paulus
4759 1.1 paulus /* fill code-like entries with r */
4760 1.1 paulus f = 1 << (k - w);
4761 1.1 paulus for (j = i >> w; j < z; j += f)
4762 1.1 paulus q[j] = r;
4763 1.1 paulus
4764 1.1 paulus /* backwards increment the k-bit code i */
4765 1.1 paulus for (j = 1 << (k - 1); i & j; j >>= 1)
4766 1.1 paulus i ^= j;
4767 1.1 paulus i ^= j;
4768 1.1 paulus
4769 1.1 paulus /* backup over finished tables */
4770 1.17 fvdl mask = (1 << w) - 1; /* needed on HP, cc -O bug */
4771 1.25 christos if (h == -1)
4772 1.25 christos return Z_BUF_ERROR;
4773 1.17 fvdl while ((i & mask) != x[h])
4774 1.1 paulus {
4775 1.1 paulus h--; /* don't need to update q */
4776 1.1 paulus w -= l;
4777 1.17 fvdl mask = (1 << w) - 1;
4778 1.1 paulus }
4779 1.1 paulus }
4780 1.1 paulus }
4781 1.1 paulus
4782 1.1 paulus
4783 1.1 paulus /* Return Z_BUF_ERROR if we were given an incomplete table */
4784 1.1 paulus return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK;
4785 1.1 paulus }
4786 1.1 paulus
4787 1.1 paulus
4788 1.17 fvdl int inflate_trees_bits(c, bb, tb, hp, z)
4789 1.1 paulus uIntf *c; /* 19 code lengths */
4790 1.1 paulus uIntf *bb; /* bits tree desired/actual depth */
4791 1.1 paulus inflate_huft * FAR *tb; /* bits tree result */
4792 1.17 fvdl inflate_huft *hp; /* space for trees */
4793 1.17 fvdl z_streamp z; /* for messages */
4794 1.1 paulus {
4795 1.1 paulus int r;
4796 1.17 fvdl uInt hn = 0; /* hufts used in space */
4797 1.17 fvdl uIntf *v; /* work area for huft_build */
4798 1.1 paulus
4799 1.17 fvdl if ((v = (uIntf*)ZALLOC(z, 19, sizeof(uInt))) == Z_NULL)
4800 1.17 fvdl return Z_MEM_ERROR;
4801 1.17 fvdl r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL,
4802 1.17 fvdl tb, bb, hp, &hn, v);
4803 1.1 paulus if (r == Z_DATA_ERROR)
4804 1.21 christos z->msg = "oversubscribed dynamic bit lengths tree";
4805 1.7 christos else if (r == Z_BUF_ERROR || *bb == 0)
4806 1.1 paulus {
4807 1.21 christos z->msg = "incomplete dynamic bit lengths tree";
4808 1.1 paulus r = Z_DATA_ERROR;
4809 1.1 paulus }
4810 1.17 fvdl ZFREE(z, v);
4811 1.1 paulus return r;
4812 1.1 paulus }
4813 1.1 paulus
4814 1.1 paulus
4815 1.17 fvdl int inflate_trees_dynamic(nl, nd, c, bl, bd, tl, td, hp, z)
4816 1.1 paulus uInt nl; /* number of literal/length codes */
4817 1.1 paulus uInt nd; /* number of distance codes */
4818 1.1 paulus uIntf *c; /* that many (total) code lengths */
4819 1.1 paulus uIntf *bl; /* literal desired/actual bit depth */
4820 1.1 paulus uIntf *bd; /* distance desired/actual bit depth */
4821 1.1 paulus inflate_huft * FAR *tl; /* literal/length tree result */
4822 1.1 paulus inflate_huft * FAR *td; /* distance tree result */
4823 1.17 fvdl inflate_huft *hp; /* space for trees */
4824 1.17 fvdl z_streamp z; /* for messages */
4825 1.1 paulus {
4826 1.1 paulus int r;
4827 1.17 fvdl uInt hn = 0; /* hufts used in space */
4828 1.17 fvdl uIntf *v; /* work area for huft_build */
4829 1.17 fvdl
4830 1.17 fvdl /* allocate work area */
4831 1.17 fvdl if ((v = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
4832 1.17 fvdl return Z_MEM_ERROR;
4833 1.1 paulus
4834 1.1 paulus /* build literal/length tree */
4835 1.17 fvdl r = huft_build(c, nl, 257, cplens, cplext, tl, bl, hp, &hn, v);
4836 1.7 christos if (r != Z_OK || *bl == 0)
4837 1.1 paulus {
4838 1.1 paulus if (r == Z_DATA_ERROR)
4839 1.21 christos z->msg = "oversubscribed literal/length tree";
4840 1.7 christos else if (r != Z_MEM_ERROR)
4841 1.1 paulus {
4842 1.21 christos z->msg = "incomplete literal/length tree";
4843 1.1 paulus r = Z_DATA_ERROR;
4844 1.1 paulus }
4845 1.17 fvdl ZFREE(z, v);
4846 1.1 paulus return r;
4847 1.1 paulus }
4848 1.1 paulus
4849 1.1 paulus /* build distance tree */
4850 1.17 fvdl r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, hp, &hn, v);
4851 1.7 christos if (r != Z_OK || (*bd == 0 && nl > 257))
4852 1.1 paulus {
4853 1.1 paulus if (r == Z_DATA_ERROR)
4854 1.21 christos z->msg = "oversubscribed distance tree";
4855 1.1 paulus else if (r == Z_BUF_ERROR) {
4856 1.1 paulus #ifdef PKZIP_BUG_WORKAROUND
4857 1.1 paulus r = Z_OK;
4858 1.1 paulus }
4859 1.1 paulus #else
4860 1.21 christos z->msg = "incomplete distance tree";
4861 1.7 christos r = Z_DATA_ERROR;
4862 1.7 christos }
4863 1.7 christos else if (r != Z_MEM_ERROR)
4864 1.7 christos {
4865 1.21 christos z->msg = "empty distance tree with lengths";
4866 1.1 paulus r = Z_DATA_ERROR;
4867 1.1 paulus }
4868 1.17 fvdl ZFREE(z, v);
4869 1.1 paulus return r;
4870 1.1 paulus #endif
4871 1.1 paulus }
4872 1.1 paulus
4873 1.1 paulus /* done */
4874 1.17 fvdl ZFREE(z, v);
4875 1.1 paulus return Z_OK;
4876 1.1 paulus }
4877 1.1 paulus
4878 1.1 paulus
4879 1.1 paulus /* build fixed tables only once--keep them here */
4880 1.17 fvdl #ifdef BUILDFIXED
4881 1.1 paulus local int fixed_built = 0;
4882 1.17 fvdl #define FIXEDH 544 /* number of hufts used by fixed tables */
4883 1.1 paulus local inflate_huft fixed_mem[FIXEDH];
4884 1.1 paulus local uInt fixed_bl;
4885 1.1 paulus local uInt fixed_bd;
4886 1.1 paulus local inflate_huft *fixed_tl;
4887 1.1 paulus local inflate_huft *fixed_td;
4888 1.17 fvdl #else
4889 1.17 fvdl
4890 1.17 fvdl /* +++ inffixed.h */
4891 1.17 fvdl /* inffixed.h -- table for decoding fixed codes
4892 1.17 fvdl * Generated automatically by the maketree.c program
4893 1.17 fvdl */
4894 1.17 fvdl
4895 1.17 fvdl /* WARNING: this file should *not* be used by applications. It is
4896 1.17 fvdl part of the implementation of the compression library and is
4897 1.17 fvdl subject to change. Applications should only use zlib.h.
4898 1.17 fvdl */
4899 1.1 paulus
4900 1.17 fvdl local uInt fixed_bl = 9;
4901 1.17 fvdl local uInt fixed_bd = 5;
4902 1.17 fvdl local inflate_huft fixed_tl[] = {
4903 1.17 fvdl {{{96,7}},256}, {{{0,8}},80}, {{{0,8}},16}, {{{84,8}},115},
4904 1.17 fvdl {{{82,7}},31}, {{{0,8}},112}, {{{0,8}},48}, {{{0,9}},192},
4905 1.17 fvdl {{{80,7}},10}, {{{0,8}},96}, {{{0,8}},32}, {{{0,9}},160},
4906 1.17 fvdl {{{0,8}},0}, {{{0,8}},128}, {{{0,8}},64}, {{{0,9}},224},
4907 1.17 fvdl {{{80,7}},6}, {{{0,8}},88}, {{{0,8}},24}, {{{0,9}},144},
4908 1.17 fvdl {{{83,7}},59}, {{{0,8}},120}, {{{0,8}},56}, {{{0,9}},208},
4909 1.17 fvdl {{{81,7}},17}, {{{0,8}},104}, {{{0,8}},40}, {{{0,9}},176},
4910 1.17 fvdl {{{0,8}},8}, {{{0,8}},136}, {{{0,8}},72}, {{{0,9}},240},
4911 1.17 fvdl {{{80,7}},4}, {{{0,8}},84}, {{{0,8}},20}, {{{85,8}},227},
4912 1.17 fvdl {{{83,7}},43}, {{{0,8}},116}, {{{0,8}},52}, {{{0,9}},200},
4913 1.17 fvdl {{{81,7}},13}, {{{0,8}},100}, {{{0,8}},36}, {{{0,9}},168},
4914 1.17 fvdl {{{0,8}},4}, {{{0,8}},132}, {{{0,8}},68}, {{{0,9}},232},
4915 1.17 fvdl {{{80,7}},8}, {{{0,8}},92}, {{{0,8}},28}, {{{0,9}},152},
4916 1.17 fvdl {{{84,7}},83}, {{{0,8}},124}, {{{0,8}},60}, {{{0,9}},216},
4917 1.17 fvdl {{{82,7}},23}, {{{0,8}},108}, {{{0,8}},44}, {{{0,9}},184},
4918 1.17 fvdl {{{0,8}},12}, {{{0,8}},140}, {{{0,8}},76}, {{{0,9}},248},
4919 1.17 fvdl {{{80,7}},3}, {{{0,8}},82}, {{{0,8}},18}, {{{85,8}},163},
4920 1.17 fvdl {{{83,7}},35}, {{{0,8}},114}, {{{0,8}},50}, {{{0,9}},196},
4921 1.17 fvdl {{{81,7}},11}, {{{0,8}},98}, {{{0,8}},34}, {{{0,9}},164},
4922 1.17 fvdl {{{0,8}},2}, {{{0,8}},130}, {{{0,8}},66}, {{{0,9}},228},
4923 1.17 fvdl {{{80,7}},7}, {{{0,8}},90}, {{{0,8}},26}, {{{0,9}},148},
4924 1.17 fvdl {{{84,7}},67}, {{{0,8}},122}, {{{0,8}},58}, {{{0,9}},212},
4925 1.17 fvdl {{{82,7}},19}, {{{0,8}},106}, {{{0,8}},42}, {{{0,9}},180},
4926 1.17 fvdl {{{0,8}},10}, {{{0,8}},138}, {{{0,8}},74}, {{{0,9}},244},
4927 1.17 fvdl {{{80,7}},5}, {{{0,8}},86}, {{{0,8}},22}, {{{192,8}},0},
4928 1.17 fvdl {{{83,7}},51}, {{{0,8}},118}, {{{0,8}},54}, {{{0,9}},204},
4929 1.17 fvdl {{{81,7}},15}, {{{0,8}},102}, {{{0,8}},38}, {{{0,9}},172},
4930 1.17 fvdl {{{0,8}},6}, {{{0,8}},134}, {{{0,8}},70}, {{{0,9}},236},
4931 1.17 fvdl {{{80,7}},9}, {{{0,8}},94}, {{{0,8}},30}, {{{0,9}},156},
4932 1.17 fvdl {{{84,7}},99}, {{{0,8}},126}, {{{0,8}},62}, {{{0,9}},220},
4933 1.17 fvdl {{{82,7}},27}, {{{0,8}},110}, {{{0,8}},46}, {{{0,9}},188},
4934 1.17 fvdl {{{0,8}},14}, {{{0,8}},142}, {{{0,8}},78}, {{{0,9}},252},
4935 1.17 fvdl {{{96,7}},256}, {{{0,8}},81}, {{{0,8}},17}, {{{85,8}},131},
4936 1.17 fvdl {{{82,7}},31}, {{{0,8}},113}, {{{0,8}},49}, {{{0,9}},194},
4937 1.17 fvdl {{{80,7}},10}, {{{0,8}},97}, {{{0,8}},33}, {{{0,9}},162},
4938 1.17 fvdl {{{0,8}},1}, {{{0,8}},129}, {{{0,8}},65}, {{{0,9}},226},
4939 1.17 fvdl {{{80,7}},6}, {{{0,8}},89}, {{{0,8}},25}, {{{0,9}},146},
4940 1.17 fvdl {{{83,7}},59}, {{{0,8}},121}, {{{0,8}},57}, {{{0,9}},210},
4941 1.17 fvdl {{{81,7}},17}, {{{0,8}},105}, {{{0,8}},41}, {{{0,9}},178},
4942 1.17 fvdl {{{0,8}},9}, {{{0,8}},137}, {{{0,8}},73}, {{{0,9}},242},
4943 1.17 fvdl {{{80,7}},4}, {{{0,8}},85}, {{{0,8}},21}, {{{80,8}},258},
4944 1.17 fvdl {{{83,7}},43}, {{{0,8}},117}, {{{0,8}},53}, {{{0,9}},202},
4945 1.17 fvdl {{{81,7}},13}, {{{0,8}},101}, {{{0,8}},37}, {{{0,9}},170},
4946 1.17 fvdl {{{0,8}},5}, {{{0,8}},133}, {{{0,8}},69}, {{{0,9}},234},
4947 1.17 fvdl {{{80,7}},8}, {{{0,8}},93}, {{{0,8}},29}, {{{0,9}},154},
4948 1.17 fvdl {{{84,7}},83}, {{{0,8}},125}, {{{0,8}},61}, {{{0,9}},218},
4949 1.17 fvdl {{{82,7}},23}, {{{0,8}},109}, {{{0,8}},45}, {{{0,9}},186},
4950 1.17 fvdl {{{0,8}},13}, {{{0,8}},141}, {{{0,8}},77}, {{{0,9}},250},
4951 1.17 fvdl {{{80,7}},3}, {{{0,8}},83}, {{{0,8}},19}, {{{85,8}},195},
4952 1.17 fvdl {{{83,7}},35}, {{{0,8}},115}, {{{0,8}},51}, {{{0,9}},198},
4953 1.17 fvdl {{{81,7}},11}, {{{0,8}},99}, {{{0,8}},35}, {{{0,9}},166},
4954 1.17 fvdl {{{0,8}},3}, {{{0,8}},131}, {{{0,8}},67}, {{{0,9}},230},
4955 1.17 fvdl {{{80,7}},7}, {{{0,8}},91}, {{{0,8}},27}, {{{0,9}},150},
4956 1.17 fvdl {{{84,7}},67}, {{{0,8}},123}, {{{0,8}},59}, {{{0,9}},214},
4957 1.17 fvdl {{{82,7}},19}, {{{0,8}},107}, {{{0,8}},43}, {{{0,9}},182},
4958 1.17 fvdl {{{0,8}},11}, {{{0,8}},139}, {{{0,8}},75}, {{{0,9}},246},
4959 1.17 fvdl {{{80,7}},5}, {{{0,8}},87}, {{{0,8}},23}, {{{192,8}},0},
4960 1.17 fvdl {{{83,7}},51}, {{{0,8}},119}, {{{0,8}},55}, {{{0,9}},206},
4961 1.17 fvdl {{{81,7}},15}, {{{0,8}},103}, {{{0,8}},39}, {{{0,9}},174},
4962 1.17 fvdl {{{0,8}},7}, {{{0,8}},135}, {{{0,8}},71}, {{{0,9}},238},
4963 1.17 fvdl {{{80,7}},9}, {{{0,8}},95}, {{{0,8}},31}, {{{0,9}},158},
4964 1.17 fvdl {{{84,7}},99}, {{{0,8}},127}, {{{0,8}},63}, {{{0,9}},222},
4965 1.17 fvdl {{{82,7}},27}, {{{0,8}},111}, {{{0,8}},47}, {{{0,9}},190},
4966 1.17 fvdl {{{0,8}},15}, {{{0,8}},143}, {{{0,8}},79}, {{{0,9}},254},
4967 1.17 fvdl {{{96,7}},256}, {{{0,8}},80}, {{{0,8}},16}, {{{84,8}},115},
4968 1.17 fvdl {{{82,7}},31}, {{{0,8}},112}, {{{0,8}},48}, {{{0,9}},193},
4969 1.17 fvdl {{{80,7}},10}, {{{0,8}},96}, {{{0,8}},32}, {{{0,9}},161},
4970 1.17 fvdl {{{0,8}},0}, {{{0,8}},128}, {{{0,8}},64}, {{{0,9}},225},
4971 1.17 fvdl {{{80,7}},6}, {{{0,8}},88}, {{{0,8}},24}, {{{0,9}},145},
4972 1.17 fvdl {{{83,7}},59}, {{{0,8}},120}, {{{0,8}},56}, {{{0,9}},209},
4973 1.17 fvdl {{{81,7}},17}, {{{0,8}},104}, {{{0,8}},40}, {{{0,9}},177},
4974 1.17 fvdl {{{0,8}},8}, {{{0,8}},136}, {{{0,8}},72}, {{{0,9}},241},
4975 1.17 fvdl {{{80,7}},4}, {{{0,8}},84}, {{{0,8}},20}, {{{85,8}},227},
4976 1.17 fvdl {{{83,7}},43}, {{{0,8}},116}, {{{0,8}},52}, {{{0,9}},201},
4977 1.17 fvdl {{{81,7}},13}, {{{0,8}},100}, {{{0,8}},36}, {{{0,9}},169},
4978 1.17 fvdl {{{0,8}},4}, {{{0,8}},132}, {{{0,8}},68}, {{{0,9}},233},
4979 1.17 fvdl {{{80,7}},8}, {{{0,8}},92}, {{{0,8}},28}, {{{0,9}},153},
4980 1.17 fvdl {{{84,7}},83}, {{{0,8}},124}, {{{0,8}},60}, {{{0,9}},217},
4981 1.17 fvdl {{{82,7}},23}, {{{0,8}},108}, {{{0,8}},44}, {{{0,9}},185},
4982 1.17 fvdl {{{0,8}},12}, {{{0,8}},140}, {{{0,8}},76}, {{{0,9}},249},
4983 1.17 fvdl {{{80,7}},3}, {{{0,8}},82}, {{{0,8}},18}, {{{85,8}},163},
4984 1.17 fvdl {{{83,7}},35}, {{{0,8}},114}, {{{0,8}},50}, {{{0,9}},197},
4985 1.17 fvdl {{{81,7}},11}, {{{0,8}},98}, {{{0,8}},34}, {{{0,9}},165},
4986 1.17 fvdl {{{0,8}},2}, {{{0,8}},130}, {{{0,8}},66}, {{{0,9}},229},
4987 1.17 fvdl {{{80,7}},7}, {{{0,8}},90}, {{{0,8}},26}, {{{0,9}},149},
4988 1.17 fvdl {{{84,7}},67}, {{{0,8}},122}, {{{0,8}},58}, {{{0,9}},213},
4989 1.17 fvdl {{{82,7}},19}, {{{0,8}},106}, {{{0,8}},42}, {{{0,9}},181},
4990 1.17 fvdl {{{0,8}},10}, {{{0,8}},138}, {{{0,8}},74}, {{{0,9}},245},
4991 1.17 fvdl {{{80,7}},5}, {{{0,8}},86}, {{{0,8}},22}, {{{192,8}},0},
4992 1.17 fvdl {{{83,7}},51}, {{{0,8}},118}, {{{0,8}},54}, {{{0,9}},205},
4993 1.17 fvdl {{{81,7}},15}, {{{0,8}},102}, {{{0,8}},38}, {{{0,9}},173},
4994 1.17 fvdl {{{0,8}},6}, {{{0,8}},134}, {{{0,8}},70}, {{{0,9}},237},
4995 1.17 fvdl {{{80,7}},9}, {{{0,8}},94}, {{{0,8}},30}, {{{0,9}},157},
4996 1.17 fvdl {{{84,7}},99}, {{{0,8}},126}, {{{0,8}},62}, {{{0,9}},221},
4997 1.17 fvdl {{{82,7}},27}, {{{0,8}},110}, {{{0,8}},46}, {{{0,9}},189},
4998 1.17 fvdl {{{0,8}},14}, {{{0,8}},142}, {{{0,8}},78}, {{{0,9}},253},
4999 1.17 fvdl {{{96,7}},256}, {{{0,8}},81}, {{{0,8}},17}, {{{85,8}},131},
5000 1.17 fvdl {{{82,7}},31}, {{{0,8}},113}, {{{0,8}},49}, {{{0,9}},195},
5001 1.17 fvdl {{{80,7}},10}, {{{0,8}},97}, {{{0,8}},33}, {{{0,9}},163},
5002 1.17 fvdl {{{0,8}},1}, {{{0,8}},129}, {{{0,8}},65}, {{{0,9}},227},
5003 1.17 fvdl {{{80,7}},6}, {{{0,8}},89}, {{{0,8}},25}, {{{0,9}},147},
5004 1.17 fvdl {{{83,7}},59}, {{{0,8}},121}, {{{0,8}},57}, {{{0,9}},211},
5005 1.17 fvdl {{{81,7}},17}, {{{0,8}},105}, {{{0,8}},41}, {{{0,9}},179},
5006 1.17 fvdl {{{0,8}},9}, {{{0,8}},137}, {{{0,8}},73}, {{{0,9}},243},
5007 1.17 fvdl {{{80,7}},4}, {{{0,8}},85}, {{{0,8}},21}, {{{80,8}},258},
5008 1.17 fvdl {{{83,7}},43}, {{{0,8}},117}, {{{0,8}},53}, {{{0,9}},203},
5009 1.17 fvdl {{{81,7}},13}, {{{0,8}},101}, {{{0,8}},37}, {{{0,9}},171},
5010 1.17 fvdl {{{0,8}},5}, {{{0,8}},133}, {{{0,8}},69}, {{{0,9}},235},
5011 1.17 fvdl {{{80,7}},8}, {{{0,8}},93}, {{{0,8}},29}, {{{0,9}},155},
5012 1.17 fvdl {{{84,7}},83}, {{{0,8}},125}, {{{0,8}},61}, {{{0,9}},219},
5013 1.17 fvdl {{{82,7}},23}, {{{0,8}},109}, {{{0,8}},45}, {{{0,9}},187},
5014 1.17 fvdl {{{0,8}},13}, {{{0,8}},141}, {{{0,8}},77}, {{{0,9}},251},
5015 1.17 fvdl {{{80,7}},3}, {{{0,8}},83}, {{{0,8}},19}, {{{85,8}},195},
5016 1.17 fvdl {{{83,7}},35}, {{{0,8}},115}, {{{0,8}},51}, {{{0,9}},199},
5017 1.17 fvdl {{{81,7}},11}, {{{0,8}},99}, {{{0,8}},35}, {{{0,9}},167},
5018 1.17 fvdl {{{0,8}},3}, {{{0,8}},131}, {{{0,8}},67}, {{{0,9}},231},
5019 1.17 fvdl {{{80,7}},7}, {{{0,8}},91}, {{{0,8}},27}, {{{0,9}},151},
5020 1.17 fvdl {{{84,7}},67}, {{{0,8}},123}, {{{0,8}},59}, {{{0,9}},215},
5021 1.17 fvdl {{{82,7}},19}, {{{0,8}},107}, {{{0,8}},43}, {{{0,9}},183},
5022 1.17 fvdl {{{0,8}},11}, {{{0,8}},139}, {{{0,8}},75}, {{{0,9}},247},
5023 1.17 fvdl {{{80,7}},5}, {{{0,8}},87}, {{{0,8}},23}, {{{192,8}},0},
5024 1.17 fvdl {{{83,7}},51}, {{{0,8}},119}, {{{0,8}},55}, {{{0,9}},207},
5025 1.17 fvdl {{{81,7}},15}, {{{0,8}},103}, {{{0,8}},39}, {{{0,9}},175},
5026 1.17 fvdl {{{0,8}},7}, {{{0,8}},135}, {{{0,8}},71}, {{{0,9}},239},
5027 1.17 fvdl {{{80,7}},9}, {{{0,8}},95}, {{{0,8}},31}, {{{0,9}},159},
5028 1.17 fvdl {{{84,7}},99}, {{{0,8}},127}, {{{0,8}},63}, {{{0,9}},223},
5029 1.17 fvdl {{{82,7}},27}, {{{0,8}},111}, {{{0,8}},47}, {{{0,9}},191},
5030 1.17 fvdl {{{0,8}},15}, {{{0,8}},143}, {{{0,8}},79}, {{{0,9}},255}
5031 1.17 fvdl };
5032 1.17 fvdl local inflate_huft fixed_td[] = {
5033 1.17 fvdl {{{80,5}},1}, {{{87,5}},257}, {{{83,5}},17}, {{{91,5}},4097},
5034 1.17 fvdl {{{81,5}},5}, {{{89,5}},1025}, {{{85,5}},65}, {{{93,5}},16385},
5035 1.17 fvdl {{{80,5}},3}, {{{88,5}},513}, {{{84,5}},33}, {{{92,5}},8193},
5036 1.17 fvdl {{{82,5}},9}, {{{90,5}},2049}, {{{86,5}},129}, {{{192,5}},24577},
5037 1.17 fvdl {{{80,5}},2}, {{{87,5}},385}, {{{83,5}},25}, {{{91,5}},6145},
5038 1.17 fvdl {{{81,5}},7}, {{{89,5}},1537}, {{{85,5}},97}, {{{93,5}},24577},
5039 1.17 fvdl {{{80,5}},4}, {{{88,5}},769}, {{{84,5}},49}, {{{92,5}},12289},
5040 1.17 fvdl {{{82,5}},13}, {{{90,5}},3073}, {{{86,5}},193}, {{{192,5}},24577}
5041 1.17 fvdl };
5042 1.17 fvdl /* --- inffixed.h */
5043 1.1 paulus
5044 1.17 fvdl #endif
5045 1.1 paulus
5046 1.1 paulus
5047 1.27 christos int inflate_trees_fixed(
5048 1.27 christos uIntf *bl, /* literal desired/actual bit depth */
5049 1.27 christos uIntf *bd, /* distance desired/actual bit depth */
5050 1.27 christos inflate_huft * FAR *tl, /* literal/length tree result */
5051 1.27 christos inflate_huft * FAR *td, /* distance tree result */
5052 1.27 christos z_streamp z __unused) /* for memory allocation */
5053 1.1 paulus {
5054 1.17 fvdl #ifdef BUILDFIXED
5055 1.17 fvdl /* build fixed tables if not already */
5056 1.1 paulus if (!fixed_built)
5057 1.1 paulus {
5058 1.1 paulus int k; /* temporary variable */
5059 1.17 fvdl uInt f = 0; /* number of hufts used in fixed_mem */
5060 1.17 fvdl uIntf *c; /* length list for huft_build */
5061 1.17 fvdl uIntf *v; /* work area for huft_build */
5062 1.17 fvdl
5063 1.17 fvdl /* allocate memory */
5064 1.17 fvdl if ((c = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
5065 1.17 fvdl return Z_MEM_ERROR;
5066 1.17 fvdl if ((v = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
5067 1.17 fvdl {
5068 1.17 fvdl ZFREE(z, c);
5069 1.17 fvdl return Z_MEM_ERROR;
5070 1.17 fvdl }
5071 1.1 paulus
5072 1.1 paulus /* literal table */
5073 1.1 paulus for (k = 0; k < 144; k++)
5074 1.1 paulus c[k] = 8;
5075 1.1 paulus for (; k < 256; k++)
5076 1.1 paulus c[k] = 9;
5077 1.1 paulus for (; k < 280; k++)
5078 1.1 paulus c[k] = 7;
5079 1.1 paulus for (; k < 288; k++)
5080 1.1 paulus c[k] = 8;
5081 1.17 fvdl fixed_bl = 9;
5082 1.17 fvdl huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl,
5083 1.17 fvdl fixed_mem, &f, v);
5084 1.1 paulus
5085 1.1 paulus /* distance table */
5086 1.1 paulus for (k = 0; k < 30; k++)
5087 1.1 paulus c[k] = 5;
5088 1.1 paulus fixed_bd = 5;
5089 1.17 fvdl huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd,
5090 1.17 fvdl fixed_mem, &f, v);
5091 1.1 paulus
5092 1.1 paulus /* done */
5093 1.17 fvdl ZFREE(z, v);
5094 1.17 fvdl ZFREE(z, c);
5095 1.1 paulus fixed_built = 1;
5096 1.1 paulus }
5097 1.17 fvdl #endif
5098 1.1 paulus *bl = fixed_bl;
5099 1.1 paulus *bd = fixed_bd;
5100 1.1 paulus *tl = fixed_tl;
5101 1.1 paulus *td = fixed_td;
5102 1.1 paulus return Z_OK;
5103 1.1 paulus }
5104 1.7 christos /* --- inftrees.c */
5105 1.1 paulus
5106 1.7 christos /* +++ infcodes.c */
5107 1.17 fvdl
5108 1.1 paulus /* infcodes.c -- process literals and length/distance pairs
5109 1.17 fvdl * Copyright (C) 1995-2002 Mark Adler
5110 1.20 perry * For conditions of distribution and use, see copyright notice in zlib.h
5111 1.1 paulus */
5112 1.1 paulus
5113 1.7 christos /* #include "zutil.h" */
5114 1.7 christos /* #include "inftrees.h" */
5115 1.7 christos /* #include "infblock.h" */
5116 1.7 christos /* #include "infcodes.h" */
5117 1.7 christos /* #include "infutil.h" */
5118 1.7 christos
5119 1.7 christos /* +++ inffast.h */
5120 1.17 fvdl
5121 1.7 christos /* inffast.h -- header to use inffast.c
5122 1.17 fvdl * Copyright (C) 1995-2002 Mark Adler
5123 1.20 perry * For conditions of distribution and use, see copyright notice in zlib.h
5124 1.7 christos */
5125 1.7 christos
5126 1.7 christos /* WARNING: this file should *not* be used by applications. It is
5127 1.7 christos part of the implementation of the compression library and is
5128 1.7 christos subject to change. Applications should only use zlib.h.
5129 1.7 christos */
5130 1.7 christos
5131 1.17 fvdl extern int inflate_fast __P((
5132 1.7 christos uInt,
5133 1.7 christos uInt,
5134 1.7 christos inflate_huft *,
5135 1.7 christos inflate_huft *,
5136 1.7 christos inflate_blocks_statef *,
5137 1.7 christos z_streamp ));
5138 1.7 christos /* --- inffast.h */
5139 1.7 christos
5140 1.1 paulus /* simplify the use of the inflate_huft type with some defines */
5141 1.1 paulus #define exop word.what.Exop
5142 1.1 paulus #define bits word.what.Bits
5143 1.1 paulus
5144 1.17 fvdl typedef enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
5145 1.1 paulus START, /* x: set up for LEN */
5146 1.1 paulus LEN, /* i: get length/literal/eob next */
5147 1.1 paulus LENEXT, /* i: getting length extra (have base) */
5148 1.1 paulus DIST, /* i: get distance next */
5149 1.1 paulus DISTEXT, /* i: getting distance extra */
5150 1.1 paulus COPY, /* o: copying bytes in window, waiting for space */
5151 1.1 paulus LIT, /* o: got literal, waiting for output space */
5152 1.1 paulus WASH, /* o: got eob, possibly still output waiting */
5153 1.1 paulus END, /* x: got eob and all data flushed */
5154 1.1 paulus BADCODE} /* x: got error */
5155 1.17 fvdl inflate_codes_mode;
5156 1.17 fvdl
5157 1.17 fvdl /* inflate codes private state */
5158 1.17 fvdl struct inflate_codes_state {
5159 1.17 fvdl
5160 1.17 fvdl /* mode */
5161 1.17 fvdl inflate_codes_mode mode; /* current inflate_codes mode */
5162 1.1 paulus
5163 1.1 paulus /* mode dependent information */
5164 1.1 paulus uInt len;
5165 1.1 paulus union {
5166 1.1 paulus struct {
5167 1.1 paulus inflate_huft *tree; /* pointer into tree */
5168 1.1 paulus uInt need; /* bits needed */
5169 1.1 paulus } code; /* if LEN or DIST, where in tree */
5170 1.1 paulus uInt lit; /* if LIT, literal */
5171 1.1 paulus struct {
5172 1.1 paulus uInt get; /* bits to get for extra */
5173 1.1 paulus uInt dist; /* distance back to copy from */
5174 1.1 paulus } copy; /* if EXT or COPY, where and how much */
5175 1.1 paulus } sub; /* submode */
5176 1.1 paulus
5177 1.1 paulus /* mode independent information */
5178 1.1 paulus Byte lbits; /* ltree bits decoded per branch */
5179 1.1 paulus Byte dbits; /* dtree bits decoder per branch */
5180 1.1 paulus inflate_huft *ltree; /* literal/length/eob tree */
5181 1.1 paulus inflate_huft *dtree; /* distance tree */
5182 1.1 paulus
5183 1.1 paulus };
5184 1.1 paulus
5185 1.1 paulus
5186 1.7 christos inflate_codes_statef *inflate_codes_new(bl, bd, tl, td, z)
5187 1.1 paulus uInt bl, bd;
5188 1.7 christos inflate_huft *tl;
5189 1.7 christos inflate_huft *td; /* need separate declaration for Borland C++ */
5190 1.7 christos z_streamp z;
5191 1.1 paulus {
5192 1.1 paulus inflate_codes_statef *c;
5193 1.1 paulus
5194 1.1 paulus if ((c = (inflate_codes_statef *)
5195 1.1 paulus ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL)
5196 1.1 paulus {
5197 1.1 paulus c->mode = START;
5198 1.1 paulus c->lbits = (Byte)bl;
5199 1.1 paulus c->dbits = (Byte)bd;
5200 1.1 paulus c->ltree = tl;
5201 1.1 paulus c->dtree = td;
5202 1.1 paulus Tracev((stderr, "inflate: codes new\n"));
5203 1.1 paulus }
5204 1.1 paulus return c;
5205 1.1 paulus }
5206 1.1 paulus
5207 1.1 paulus
5208 1.7 christos int inflate_codes(s, z, r)
5209 1.1 paulus inflate_blocks_statef *s;
5210 1.7 christos z_streamp z;
5211 1.1 paulus int r;
5212 1.1 paulus {
5213 1.1 paulus uInt j; /* temporary storage */
5214 1.1 paulus inflate_huft *t; /* temporary pointer */
5215 1.1 paulus uInt e; /* extra bits or operation */
5216 1.1 paulus uLong b; /* bit buffer */
5217 1.1 paulus uInt k; /* bits in bit buffer */
5218 1.1 paulus Bytef *p; /* input data pointer */
5219 1.1 paulus uInt n; /* bytes available there */
5220 1.1 paulus Bytef *q; /* output window write pointer */
5221 1.1 paulus uInt m; /* bytes to end of window or read pointer */
5222 1.1 paulus Bytef *f; /* pointer to copy strings from */
5223 1.1 paulus inflate_codes_statef *c = s->sub.decode.codes; /* codes state */
5224 1.1 paulus
5225 1.1 paulus /* copy input/output information to locals (UPDATE macro restores) */
5226 1.1 paulus LOAD
5227 1.1 paulus
5228 1.1 paulus /* process input and output based on current state */
5229 1.1 paulus while (1) switch (c->mode)
5230 1.1 paulus { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
5231 1.1 paulus case START: /* x: set up for LEN */
5232 1.1 paulus #ifndef SLOW
5233 1.1 paulus if (m >= 258 && n >= 10)
5234 1.1 paulus {
5235 1.1 paulus UPDATE
5236 1.1 paulus r = inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z);
5237 1.1 paulus LOAD
5238 1.1 paulus if (r != Z_OK)
5239 1.1 paulus {
5240 1.1 paulus c->mode = r == Z_STREAM_END ? WASH : BADCODE;
5241 1.1 paulus break;
5242 1.1 paulus }
5243 1.1 paulus }
5244 1.1 paulus #endif /* !SLOW */
5245 1.1 paulus c->sub.code.need = c->lbits;
5246 1.1 paulus c->sub.code.tree = c->ltree;
5247 1.1 paulus c->mode = LEN;
5248 1.1 paulus case LEN: /* i: get length/literal/eob next */
5249 1.1 paulus j = c->sub.code.need;
5250 1.1 paulus NEEDBITS(j)
5251 1.1 paulus t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
5252 1.1 paulus DUMPBITS(t->bits)
5253 1.1 paulus e = (uInt)(t->exop);
5254 1.1 paulus if (e == 0) /* literal */
5255 1.1 paulus {
5256 1.1 paulus c->sub.lit = t->base;
5257 1.1 paulus Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5258 1.1 paulus "inflate: literal '%c'\n" :
5259 1.1 paulus "inflate: literal 0x%02x\n", t->base));
5260 1.1 paulus c->mode = LIT;
5261 1.1 paulus break;
5262 1.1 paulus }
5263 1.1 paulus if (e & 16) /* length */
5264 1.1 paulus {
5265 1.1 paulus c->sub.copy.get = e & 15;
5266 1.1 paulus c->len = t->base;
5267 1.1 paulus c->mode = LENEXT;
5268 1.1 paulus break;
5269 1.1 paulus }
5270 1.1 paulus if ((e & 64) == 0) /* next table */
5271 1.1 paulus {
5272 1.1 paulus c->sub.code.need = e;
5273 1.17 fvdl c->sub.code.tree = t + t->base;
5274 1.1 paulus break;
5275 1.1 paulus }
5276 1.1 paulus if (e & 32) /* end of block */
5277 1.1 paulus {
5278 1.1 paulus Tracevv((stderr, "inflate: end of block\n"));
5279 1.1 paulus c->mode = WASH;
5280 1.1 paulus break;
5281 1.1 paulus }
5282 1.1 paulus c->mode = BADCODE; /* invalid code */
5283 1.21 christos z->msg = "invalid literal/length code";
5284 1.1 paulus r = Z_DATA_ERROR;
5285 1.1 paulus LEAVE
5286 1.1 paulus case LENEXT: /* i: getting length extra (have base) */
5287 1.1 paulus j = c->sub.copy.get;
5288 1.1 paulus NEEDBITS(j)
5289 1.1 paulus c->len += (uInt)b & inflate_mask[j];
5290 1.1 paulus DUMPBITS(j)
5291 1.1 paulus c->sub.code.need = c->dbits;
5292 1.1 paulus c->sub.code.tree = c->dtree;
5293 1.1 paulus Tracevv((stderr, "inflate: length %u\n", c->len));
5294 1.1 paulus c->mode = DIST;
5295 1.1 paulus case DIST: /* i: get distance next */
5296 1.1 paulus j = c->sub.code.need;
5297 1.1 paulus NEEDBITS(j)
5298 1.1 paulus t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
5299 1.1 paulus DUMPBITS(t->bits)
5300 1.1 paulus e = (uInt)(t->exop);
5301 1.1 paulus if (e & 16) /* distance */
5302 1.1 paulus {
5303 1.1 paulus c->sub.copy.get = e & 15;
5304 1.1 paulus c->sub.copy.dist = t->base;
5305 1.1 paulus c->mode = DISTEXT;
5306 1.1 paulus break;
5307 1.1 paulus }
5308 1.1 paulus if ((e & 64) == 0) /* next table */
5309 1.1 paulus {
5310 1.1 paulus c->sub.code.need = e;
5311 1.17 fvdl c->sub.code.tree = t + t->base;
5312 1.1 paulus break;
5313 1.1 paulus }
5314 1.1 paulus c->mode = BADCODE; /* invalid code */
5315 1.21 christos z->msg = "invalid distance code";
5316 1.1 paulus r = Z_DATA_ERROR;
5317 1.1 paulus LEAVE
5318 1.1 paulus case DISTEXT: /* i: getting distance extra */
5319 1.1 paulus j = c->sub.copy.get;
5320 1.1 paulus NEEDBITS(j)
5321 1.1 paulus c->sub.copy.dist += (uInt)b & inflate_mask[j];
5322 1.1 paulus DUMPBITS(j)
5323 1.1 paulus Tracevv((stderr, "inflate: distance %u\n", c->sub.copy.dist));
5324 1.1 paulus c->mode = COPY;
5325 1.1 paulus case COPY: /* o: copying bytes in window, waiting for space */
5326 1.1 paulus f = q - c->sub.copy.dist;
5327 1.17 fvdl while (f < s->window) /* modulo window size-"while" instead */
5328 1.17 fvdl f += s->end - s->window; /* of "if" handles invalid distances */
5329 1.1 paulus while (c->len)
5330 1.1 paulus {
5331 1.1 paulus NEEDOUT
5332 1.1 paulus OUTBYTE(*f++)
5333 1.1 paulus if (f == s->end)
5334 1.1 paulus f = s->window;
5335 1.1 paulus c->len--;
5336 1.1 paulus }
5337 1.1 paulus c->mode = START;
5338 1.1 paulus break;
5339 1.1 paulus case LIT: /* o: got literal, waiting for output space */
5340 1.1 paulus NEEDOUT
5341 1.1 paulus OUTBYTE(c->sub.lit)
5342 1.1 paulus c->mode = START;
5343 1.1 paulus break;
5344 1.1 paulus case WASH: /* o: got eob, possibly more output */
5345 1.17 fvdl if (k > 7) /* return unused byte, if any */
5346 1.17 fvdl {
5347 1.17 fvdl Assert(k < 16, "inflate_codes grabbed too many bytes")
5348 1.17 fvdl k -= 8;
5349 1.17 fvdl n++;
5350 1.17 fvdl p--; /* can always return one */
5351 1.17 fvdl }
5352 1.1 paulus FLUSH
5353 1.1 paulus if (s->read != s->write)
5354 1.1 paulus LEAVE
5355 1.1 paulus c->mode = END;
5356 1.1 paulus case END:
5357 1.1 paulus r = Z_STREAM_END;
5358 1.1 paulus LEAVE
5359 1.1 paulus case BADCODE: /* x: got error */
5360 1.1 paulus r = Z_DATA_ERROR;
5361 1.1 paulus LEAVE
5362 1.1 paulus default:
5363 1.1 paulus r = Z_STREAM_ERROR;
5364 1.1 paulus LEAVE
5365 1.1 paulus }
5366 1.17 fvdl #ifdef NEED_DUMMY_RETURN
5367 1.17 fvdl return Z_STREAM_ERROR; /* Some dumb compilers complain without this */
5368 1.17 fvdl #endif
5369 1.1 paulus }
5370 1.1 paulus
5371 1.1 paulus
5372 1.7 christos void inflate_codes_free(c, z)
5373 1.1 paulus inflate_codes_statef *c;
5374 1.7 christos z_streamp z;
5375 1.1 paulus {
5376 1.7 christos ZFREE(z, c);
5377 1.1 paulus Tracev((stderr, "inflate: codes free\n"));
5378 1.1 paulus }
5379 1.7 christos /* --- infcodes.c */
5380 1.1 paulus
5381 1.7 christos /* +++ infutil.c */
5382 1.17 fvdl
5383 1.1 paulus /* inflate_util.c -- data and routines common to blocks and codes
5384 1.17 fvdl * Copyright (C) 1995-2002 Mark Adler
5385 1.20 perry * For conditions of distribution and use, see copyright notice in zlib.h
5386 1.1 paulus */
5387 1.1 paulus
5388 1.7 christos /* #include "zutil.h" */
5389 1.7 christos /* #include "infblock.h" */
5390 1.7 christos /* #include "inftrees.h" */
5391 1.7 christos /* #include "infcodes.h" */
5392 1.7 christos /* #include "infutil.h" */
5393 1.7 christos
5394 1.7 christos #ifndef NO_DUMMY_DECL
5395 1.7 christos struct inflate_codes_state {int dummy;}; /* for buggy compilers */
5396 1.7 christos #endif
5397 1.7 christos
5398 1.7 christos /* And'ing with mask[n] masks the lower n bits */
5399 1.17 fvdl uInt inflate_mask[17] = {
5400 1.7 christos 0x0000,
5401 1.7 christos 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
5402 1.7 christos 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
5403 1.7 christos };
5404 1.7 christos
5405 1.7 christos
5406 1.1 paulus /* copy as much as possible from the sliding window to the output area */
5407 1.7 christos int inflate_flush(s, z, r)
5408 1.1 paulus inflate_blocks_statef *s;
5409 1.7 christos z_streamp z;
5410 1.1 paulus int r;
5411 1.1 paulus {
5412 1.1 paulus uInt n;
5413 1.7 christos Bytef *p;
5414 1.7 christos Bytef *q;
5415 1.1 paulus
5416 1.1 paulus /* local copies of source and destination pointers */
5417 1.1 paulus p = z->next_out;
5418 1.1 paulus q = s->read;
5419 1.1 paulus
5420 1.1 paulus /* compute number of bytes to copy as far as end of window */
5421 1.1 paulus n = (uInt)((q <= s->write ? s->write : s->end) - q);
5422 1.1 paulus if (n > z->avail_out) n = z->avail_out;
5423 1.1 paulus if (n && r == Z_BUF_ERROR) r = Z_OK;
5424 1.1 paulus
5425 1.1 paulus /* update counters */
5426 1.1 paulus z->avail_out -= n;
5427 1.1 paulus z->total_out += n;
5428 1.1 paulus
5429 1.1 paulus /* update check information */
5430 1.1 paulus if (s->checkfn != Z_NULL)
5431 1.7 christos z->adler = s->check = (*s->checkfn)(s->check, q, n);
5432 1.1 paulus
5433 1.1 paulus /* copy as far as end of window */
5434 1.7 christos if (p != Z_NULL) {
5435 1.1 paulus zmemcpy(p, q, n);
5436 1.1 paulus p += n;
5437 1.1 paulus }
5438 1.1 paulus q += n;
5439 1.1 paulus
5440 1.1 paulus /* see if more to copy at beginning of window */
5441 1.1 paulus if (q == s->end)
5442 1.1 paulus {
5443 1.1 paulus /* wrap pointers */
5444 1.1 paulus q = s->window;
5445 1.1 paulus if (s->write == s->end)
5446 1.1 paulus s->write = s->window;
5447 1.1 paulus
5448 1.1 paulus /* compute bytes to copy */
5449 1.1 paulus n = (uInt)(s->write - q);
5450 1.1 paulus if (n > z->avail_out) n = z->avail_out;
5451 1.1 paulus if (n && r == Z_BUF_ERROR) r = Z_OK;
5452 1.1 paulus
5453 1.1 paulus /* update counters */
5454 1.1 paulus z->avail_out -= n;
5455 1.1 paulus z->total_out += n;
5456 1.1 paulus
5457 1.1 paulus /* update check information */
5458 1.1 paulus if (s->checkfn != Z_NULL)
5459 1.7 christos z->adler = s->check = (*s->checkfn)(s->check, q, n);
5460 1.1 paulus
5461 1.1 paulus /* copy */
5462 1.17 fvdl if (p != NULL) {
5463 1.1 paulus zmemcpy(p, q, n);
5464 1.1 paulus p += n;
5465 1.1 paulus }
5466 1.1 paulus q += n;
5467 1.1 paulus }
5468 1.1 paulus
5469 1.1 paulus /* update pointers */
5470 1.1 paulus z->next_out = p;
5471 1.1 paulus s->read = q;
5472 1.1 paulus
5473 1.1 paulus /* done */
5474 1.1 paulus return r;
5475 1.1 paulus }
5476 1.7 christos /* --- infutil.c */
5477 1.1 paulus
5478 1.7 christos /* +++ inffast.c */
5479 1.17 fvdl
5480 1.1 paulus /* inffast.c -- process literals and length/distance pairs fast
5481 1.17 fvdl * Copyright (C) 1995-2002 Mark Adler
5482 1.20 perry * For conditions of distribution and use, see copyright notice in zlib.h
5483 1.1 paulus */
5484 1.1 paulus
5485 1.7 christos /* #include "zutil.h" */
5486 1.7 christos /* #include "inftrees.h" */
5487 1.7 christos /* #include "infblock.h" */
5488 1.7 christos /* #include "infcodes.h" */
5489 1.7 christos /* #include "infutil.h" */
5490 1.7 christos /* #include "inffast.h" */
5491 1.7 christos
5492 1.7 christos #ifndef NO_DUMMY_DECL
5493 1.7 christos struct inflate_codes_state {int dummy;}; /* for buggy compilers */
5494 1.7 christos #endif
5495 1.7 christos
5496 1.1 paulus /* simplify the use of the inflate_huft type with some defines */
5497 1.1 paulus #define exop word.what.Exop
5498 1.1 paulus #define bits word.what.Bits
5499 1.1 paulus
5500 1.1 paulus /* macros for bit input with no checking and for returning unused bytes */
5501 1.1 paulus #define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}}
5502 1.17 fvdl #define UNGRAB {c=z->avail_in-n;c=(k>>3)<c?k>>3:c;n+=c;p-=c;k-=c<<3;}
5503 1.1 paulus
5504 1.1 paulus /* Called with number of bytes left to write in window at least 258
5505 1.1 paulus (the maximum string length) and number of input bytes available
5506 1.1 paulus at least ten. The ten bytes are six bytes for the longest length/
5507 1.1 paulus distance pair plus four bytes for overloading the bit buffer. */
5508 1.1 paulus
5509 1.7 christos int inflate_fast(bl, bd, tl, td, s, z)
5510 1.1 paulus uInt bl, bd;
5511 1.7 christos inflate_huft *tl;
5512 1.7 christos inflate_huft *td; /* need separate declaration for Borland C++ */
5513 1.1 paulus inflate_blocks_statef *s;
5514 1.7 christos z_streamp z;
5515 1.1 paulus {
5516 1.1 paulus inflate_huft *t; /* temporary pointer */
5517 1.1 paulus uInt e; /* extra bits or operation */
5518 1.1 paulus uLong b; /* bit buffer */
5519 1.1 paulus uInt k; /* bits in bit buffer */
5520 1.1 paulus Bytef *p; /* input data pointer */
5521 1.1 paulus uInt n; /* bytes available there */
5522 1.1 paulus Bytef *q; /* output window write pointer */
5523 1.1 paulus uInt m; /* bytes to end of window or read pointer */
5524 1.1 paulus uInt ml; /* mask for literal/length tree */
5525 1.1 paulus uInt md; /* mask for distance tree */
5526 1.1 paulus uInt c; /* bytes to copy */
5527 1.1 paulus uInt d; /* distance back to copy from */
5528 1.1 paulus Bytef *r; /* copy source pointer */
5529 1.1 paulus
5530 1.1 paulus /* load input, output, bit values */
5531 1.1 paulus LOAD
5532 1.1 paulus
5533 1.1 paulus /* initialize masks */
5534 1.1 paulus ml = inflate_mask[bl];
5535 1.1 paulus md = inflate_mask[bd];
5536 1.1 paulus
5537 1.1 paulus /* do until not enough input or output space for fast loop */
5538 1.1 paulus do { /* assume called with m >= 258 && n >= 10 */
5539 1.1 paulus /* get literal/length code */
5540 1.1 paulus GRABBITS(20) /* max bits for literal/length code */
5541 1.1 paulus if ((e = (t = tl + ((uInt)b & ml))->exop) == 0)
5542 1.1 paulus {
5543 1.1 paulus DUMPBITS(t->bits)
5544 1.1 paulus Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5545 1.1 paulus "inflate: * literal '%c'\n" :
5546 1.1 paulus "inflate: * literal 0x%02x\n", t->base));
5547 1.1 paulus *q++ = (Byte)t->base;
5548 1.1 paulus m--;
5549 1.1 paulus continue;
5550 1.1 paulus }
5551 1.1 paulus do {
5552 1.1 paulus DUMPBITS(t->bits)
5553 1.1 paulus if (e & 16)
5554 1.1 paulus {
5555 1.1 paulus /* get extra bits for length */
5556 1.1 paulus e &= 15;
5557 1.1 paulus c = t->base + ((uInt)b & inflate_mask[e]);
5558 1.1 paulus DUMPBITS(e)
5559 1.1 paulus Tracevv((stderr, "inflate: * length %u\n", c));
5560 1.1 paulus
5561 1.1 paulus /* decode distance base of block to copy */
5562 1.1 paulus GRABBITS(15); /* max bits for distance code */
5563 1.1 paulus e = (t = td + ((uInt)b & md))->exop;
5564 1.1 paulus do {
5565 1.1 paulus DUMPBITS(t->bits)
5566 1.1 paulus if (e & 16)
5567 1.1 paulus {
5568 1.1 paulus /* get extra bits to add to distance base */
5569 1.1 paulus e &= 15;
5570 1.1 paulus GRABBITS(e) /* get extra bits (up to 13) */
5571 1.1 paulus d = t->base + ((uInt)b & inflate_mask[e]);
5572 1.1 paulus DUMPBITS(e)
5573 1.1 paulus Tracevv((stderr, "inflate: * distance %u\n", d));
5574 1.1 paulus
5575 1.1 paulus /* do the copy */
5576 1.1 paulus m -= c;
5577 1.17 fvdl r = q - d;
5578 1.17 fvdl if (r < s->window) /* wrap if needed */
5579 1.1 paulus {
5580 1.17 fvdl do {
5581 1.17 fvdl r += s->end - s->window; /* force pointer in window */
5582 1.17 fvdl } while (r < s->window); /* covers invalid distances */
5583 1.17 fvdl e = s->end - r;
5584 1.17 fvdl if (c > e)
5585 1.1 paulus {
5586 1.17 fvdl c -= e; /* wrapped copy */
5587 1.1 paulus do {
5588 1.17 fvdl *q++ = *r++;
5589 1.1 paulus } while (--e);
5590 1.17 fvdl r = s->window;
5591 1.17 fvdl do {
5592 1.17 fvdl *q++ = *r++;
5593 1.17 fvdl } while (--c);
5594 1.1 paulus }
5595 1.17 fvdl else /* normal copy */
5596 1.17 fvdl {
5597 1.17 fvdl *q++ = *r++; c--;
5598 1.17 fvdl *q++ = *r++; c--;
5599 1.17 fvdl do {
5600 1.17 fvdl *q++ = *r++;
5601 1.17 fvdl } while (--c);
5602 1.17 fvdl }
5603 1.17 fvdl }
5604 1.17 fvdl else /* normal copy */
5605 1.17 fvdl {
5606 1.17 fvdl *q++ = *r++; c--;
5607 1.17 fvdl *q++ = *r++; c--;
5608 1.17 fvdl do {
5609 1.17 fvdl *q++ = *r++;
5610 1.17 fvdl } while (--c);
5611 1.1 paulus }
5612 1.1 paulus break;
5613 1.1 paulus }
5614 1.1 paulus else if ((e & 64) == 0)
5615 1.17 fvdl {
5616 1.17 fvdl t += t->base;
5617 1.17 fvdl e = (t += ((uInt)b & inflate_mask[e]))->exop;
5618 1.17 fvdl }
5619 1.1 paulus else
5620 1.1 paulus {
5621 1.21 christos z->msg = "invalid distance code";
5622 1.1 paulus UNGRAB
5623 1.1 paulus UPDATE
5624 1.1 paulus return Z_DATA_ERROR;
5625 1.1 paulus }
5626 1.1 paulus } while (1);
5627 1.1 paulus break;
5628 1.1 paulus }
5629 1.1 paulus if ((e & 64) == 0)
5630 1.1 paulus {
5631 1.17 fvdl t += t->base;
5632 1.17 fvdl if ((e = (t += ((uInt)b & inflate_mask[e]))->exop) == 0)
5633 1.1 paulus {
5634 1.1 paulus DUMPBITS(t->bits)
5635 1.1 paulus Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5636 1.1 paulus "inflate: * literal '%c'\n" :
5637 1.1 paulus "inflate: * literal 0x%02x\n", t->base));
5638 1.1 paulus *q++ = (Byte)t->base;
5639 1.1 paulus m--;
5640 1.1 paulus break;
5641 1.1 paulus }
5642 1.1 paulus }
5643 1.1 paulus else if (e & 32)
5644 1.1 paulus {
5645 1.1 paulus Tracevv((stderr, "inflate: * end of block\n"));
5646 1.1 paulus UNGRAB
5647 1.1 paulus UPDATE
5648 1.1 paulus return Z_STREAM_END;
5649 1.1 paulus }
5650 1.1 paulus else
5651 1.1 paulus {
5652 1.21 christos z->msg = "invalid literal/length code";
5653 1.1 paulus UNGRAB
5654 1.1 paulus UPDATE
5655 1.1 paulus return Z_DATA_ERROR;
5656 1.1 paulus }
5657 1.1 paulus } while (1);
5658 1.1 paulus } while (m >= 258 && n >= 10);
5659 1.1 paulus
5660 1.1 paulus /* not enough input or output--restore pointers and return */
5661 1.1 paulus UNGRAB
5662 1.1 paulus UPDATE
5663 1.1 paulus return Z_OK;
5664 1.1 paulus }
5665 1.7 christos /* --- inffast.c */
5666 1.1 paulus
5667 1.7 christos /* +++ zutil.c */
5668 1.17 fvdl
5669 1.1 paulus /* zutil.c -- target dependent utility functions for the compression library
5670 1.17 fvdl * Copyright (C) 1995-2002 Jean-loup Gailly.
5671 1.20 perry * For conditions of distribution and use, see copyright notice in zlib.h
5672 1.1 paulus */
5673 1.1 paulus
5674 1.17 fvdl /* @(#) Id */
5675 1.7 christos
5676 1.7 christos #ifdef DEBUG_ZLIB
5677 1.7 christos #include <stdio.h>
5678 1.7 christos #endif
5679 1.7 christos
5680 1.7 christos /* #include "zutil.h" */
5681 1.1 paulus
5682 1.7 christos #ifndef NO_DUMMY_DECL
5683 1.7 christos struct internal_state {int dummy;}; /* for buggy compilers */
5684 1.7 christos #endif
5685 1.7 christos
5686 1.7 christos #ifndef STDC
5687 1.17 fvdl extern void exit __P((int));
5688 1.7 christos #endif
5689 1.1 paulus
5690 1.17 fvdl const char *z_errmsg[10] = {
5691 1.7 christos "need dictionary", /* Z_NEED_DICT 2 */
5692 1.7 christos "stream end", /* Z_STREAM_END 1 */
5693 1.7 christos "", /* Z_OK 0 */
5694 1.7 christos "file error", /* Z_ERRNO (-1) */
5695 1.7 christos "stream error", /* Z_STREAM_ERROR (-2) */
5696 1.7 christos "data error", /* Z_DATA_ERROR (-3) */
5697 1.7 christos "insufficient memory", /* Z_MEM_ERROR (-4) */
5698 1.7 christos "buffer error", /* Z_BUF_ERROR (-5) */
5699 1.7 christos "incompatible version",/* Z_VERSION_ERROR (-6) */
5700 1.1 paulus ""};
5701 1.1 paulus
5702 1.1 paulus
5703 1.19 kristerw #if 0
5704 1.17 fvdl const char * ZEXPORT zlibVersion()
5705 1.7 christos {
5706 1.7 christos return ZLIB_VERSION;
5707 1.7 christos }
5708 1.19 kristerw #endif
5709 1.7 christos
5710 1.7 christos #ifdef DEBUG_ZLIB
5711 1.17 fvdl
5712 1.17 fvdl # ifndef verbose
5713 1.17 fvdl # define verbose 0
5714 1.17 fvdl # endif
5715 1.17 fvdl int z_verbose = verbose;
5716 1.17 fvdl
5717 1.7 christos void z_error (m)
5718 1.7 christos char *m;
5719 1.7 christos {
5720 1.7 christos fprintf(stderr, "%s\n", m);
5721 1.7 christos exit(1);
5722 1.7 christos }
5723 1.7 christos #endif
5724 1.7 christos
5725 1.17 fvdl /* exported to allow conversion of error code to string for compress() and
5726 1.17 fvdl * uncompress()
5727 1.17 fvdl */
5728 1.19 kristerw #if 0
5729 1.17 fvdl const char * ZEXPORT zError(err)
5730 1.17 fvdl int err;
5731 1.17 fvdl {
5732 1.17 fvdl return ERR_MSG(err);
5733 1.17 fvdl }
5734 1.19 kristerw #endif
5735 1.17 fvdl
5736 1.17 fvdl
5737 1.7 christos #ifndef HAVE_MEMCPY
5738 1.7 christos
5739 1.7 christos void zmemcpy(dest, source, len)
5740 1.7 christos Bytef* dest;
5741 1.17 fvdl const Bytef* source;
5742 1.7 christos uInt len;
5743 1.7 christos {
5744 1.7 christos if (len == 0) return;
5745 1.7 christos do {
5746 1.7 christos *dest++ = *source++; /* ??? to be unrolled */
5747 1.7 christos } while (--len != 0);
5748 1.7 christos }
5749 1.7 christos
5750 1.7 christos int zmemcmp(s1, s2, len)
5751 1.17 fvdl const Bytef* s1;
5752 1.17 fvdl const Bytef* s2;
5753 1.7 christos uInt len;
5754 1.7 christos {
5755 1.7 christos uInt j;
5756 1.7 christos
5757 1.7 christos for (j = 0; j < len; j++) {
5758 1.7 christos if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1;
5759 1.7 christos }
5760 1.7 christos return 0;
5761 1.7 christos }
5762 1.7 christos
5763 1.7 christos void zmemzero(dest, len)
5764 1.7 christos Bytef* dest;
5765 1.7 christos uInt len;
5766 1.7 christos {
5767 1.7 christos if (len == 0) return;
5768 1.7 christos do {
5769 1.7 christos *dest++ = 0; /* ??? to be unrolled */
5770 1.7 christos } while (--len != 0);
5771 1.7 christos }
5772 1.7 christos #endif
5773 1.7 christos
5774 1.7 christos #ifdef __TURBOC__
5775 1.7 christos #if (defined( __BORLANDC__) || !defined(SMALL_MEDIUM)) && !defined(__32BIT__)
5776 1.7 christos /* Small and medium model in Turbo C are for now limited to near allocation
5777 1.7 christos * with reduced MAX_WBITS and MAX_MEM_LEVEL
5778 1.7 christos */
5779 1.7 christos # define MY_ZCALLOC
5780 1.7 christos
5781 1.7 christos /* Turbo C malloc() does not allow dynamic allocation of 64K bytes
5782 1.7 christos * and farmalloc(64K) returns a pointer with an offset of 8, so we
5783 1.7 christos * must fix the pointer. Warning: the pointer must be put back to its
5784 1.7 christos * original form in order to free it, use zcfree().
5785 1.7 christos */
5786 1.7 christos
5787 1.7 christos #define MAX_PTR 10
5788 1.7 christos /* 10*64K = 640K */
5789 1.7 christos
5790 1.7 christos local int next_ptr = 0;
5791 1.7 christos
5792 1.7 christos typedef struct ptr_table_s {
5793 1.7 christos voidpf org_ptr;
5794 1.7 christos voidpf new_ptr;
5795 1.7 christos } ptr_table;
5796 1.7 christos
5797 1.7 christos local ptr_table table[MAX_PTR];
5798 1.7 christos /* This table is used to remember the original form of pointers
5799 1.7 christos * to large buffers (64K). Such pointers are normalized with a zero offset.
5800 1.7 christos * Since MSDOS is not a preemptive multitasking OS, this table is not
5801 1.7 christos * protected from concurrent access. This hack doesn't work anyway on
5802 1.7 christos * a protected system like OS/2. Use Microsoft C instead.
5803 1.7 christos */
5804 1.7 christos
5805 1.7 christos voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
5806 1.7 christos {
5807 1.7 christos voidpf buf = opaque; /* just to make some compilers happy */
5808 1.7 christos ulg bsize = (ulg)items*size;
5809 1.7 christos
5810 1.7 christos /* If we allocate less than 65520 bytes, we assume that farmalloc
5811 1.7 christos * will return a usable pointer which doesn't have to be normalized.
5812 1.7 christos */
5813 1.7 christos if (bsize < 65520L) {
5814 1.7 christos buf = farmalloc(bsize);
5815 1.7 christos if (*(ush*)&buf != 0) return buf;
5816 1.7 christos } else {
5817 1.7 christos buf = farmalloc(bsize + 16L);
5818 1.7 christos }
5819 1.7 christos if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
5820 1.7 christos table[next_ptr].org_ptr = buf;
5821 1.7 christos
5822 1.7 christos /* Normalize the pointer to seg:0 */
5823 1.7 christos *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
5824 1.7 christos *(ush*)&buf = 0;
5825 1.7 christos table[next_ptr++].new_ptr = buf;
5826 1.7 christos return buf;
5827 1.7 christos }
5828 1.7 christos
5829 1.7 christos void zcfree (voidpf opaque, voidpf ptr)
5830 1.7 christos {
5831 1.7 christos int n;
5832 1.7 christos if (*(ush*)&ptr != 0) { /* object < 64K */
5833 1.7 christos farfree(ptr);
5834 1.7 christos return;
5835 1.7 christos }
5836 1.7 christos /* Find the original pointer */
5837 1.7 christos for (n = 0; n < next_ptr; n++) {
5838 1.7 christos if (ptr != table[n].new_ptr) continue;
5839 1.7 christos
5840 1.7 christos farfree(table[n].org_ptr);
5841 1.7 christos while (++n < next_ptr) {
5842 1.7 christos table[n-1] = table[n];
5843 1.7 christos }
5844 1.7 christos next_ptr--;
5845 1.7 christos return;
5846 1.7 christos }
5847 1.7 christos ptr = opaque; /* just to make some compilers happy */
5848 1.7 christos Assert(0, "zcfree: ptr not found");
5849 1.7 christos }
5850 1.7 christos #endif
5851 1.7 christos #endif /* __TURBOC__ */
5852 1.7 christos
5853 1.7 christos
5854 1.7 christos #if defined(M_I86) && !defined(__32BIT__)
5855 1.7 christos /* Microsoft C in 16-bit mode */
5856 1.7 christos
5857 1.7 christos # define MY_ZCALLOC
5858 1.7 christos
5859 1.17 fvdl #if (!defined(_MSC_VER) || (_MSC_VER <= 600))
5860 1.7 christos # define _halloc halloc
5861 1.7 christos # define _hfree hfree
5862 1.7 christos #endif
5863 1.7 christos
5864 1.7 christos voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
5865 1.7 christos {
5866 1.7 christos if (opaque) opaque = 0; /* to make compiler happy */
5867 1.7 christos return _halloc((long)items, size);
5868 1.7 christos }
5869 1.7 christos
5870 1.7 christos void zcfree (voidpf opaque, voidpf ptr)
5871 1.7 christos {
5872 1.7 christos if (opaque) opaque = 0; /* to make compiler happy */
5873 1.7 christos _hfree(ptr);
5874 1.7 christos }
5875 1.7 christos
5876 1.7 christos #endif /* MSC */
5877 1.7 christos
5878 1.7 christos
5879 1.7 christos #ifndef MY_ZCALLOC /* Any system without a special alloc function */
5880 1.7 christos
5881 1.7 christos #ifndef STDC
5882 1.17 fvdl extern voidp calloc __P((uInt items, uInt size));
5883 1.17 fvdl extern void free __P((voidpf ptr));
5884 1.7 christos #endif
5885 1.7 christos
5886 1.7 christos voidpf zcalloc (opaque, items, size)
5887 1.7 christos voidpf opaque;
5888 1.7 christos unsigned items;
5889 1.7 christos unsigned size;
5890 1.7 christos {
5891 1.7 christos if (opaque) items += size - size; /* make compiler happy */
5892 1.7 christos return (voidpf)calloc(items, size);
5893 1.7 christos }
5894 1.7 christos
5895 1.7 christos void zcfree (opaque, ptr)
5896 1.7 christos voidpf opaque;
5897 1.7 christos voidpf ptr;
5898 1.7 christos {
5899 1.7 christos free(ptr);
5900 1.7 christos if (opaque) return; /* make compiler happy */
5901 1.7 christos }
5902 1.7 christos
5903 1.7 christos #endif /* MY_ZCALLOC */
5904 1.7 christos /* --- zutil.c */
5905 1.7 christos
5906 1.7 christos /* +++ adler32.c */
5907 1.1 paulus /* adler32.c -- compute the Adler-32 checksum of a data stream
5908 1.17 fvdl * Copyright (C) 1995-2002 Mark Adler
5909 1.20 perry * For conditions of distribution and use, see copyright notice in zlib.h
5910 1.1 paulus */
5911 1.1 paulus
5912 1.27 christos /* @(#) $Id: zlib.c,v 1.27 2006/10/12 01:32:30 christos Exp $ */
5913 1.7 christos
5914 1.7 christos /* #include "zlib.h" */
5915 1.1 paulus
5916 1.1 paulus #define BASE 65521L /* largest prime smaller than 65536 */
5917 1.1 paulus #define NMAX 5552
5918 1.1 paulus /* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
5919 1.1 paulus
5920 1.7 christos #define DO1(buf,i) {s1 += buf[i]; s2 += s1;}
5921 1.7 christos #define DO2(buf,i) DO1(buf,i); DO1(buf,i+1);
5922 1.7 christos #define DO4(buf,i) DO2(buf,i); DO2(buf,i+2);
5923 1.7 christos #define DO8(buf,i) DO4(buf,i); DO4(buf,i+4);
5924 1.7 christos #define DO16(buf) DO8(buf,0); DO8(buf,8);
5925 1.1 paulus
5926 1.1 paulus /* ========================================================================= */
5927 1.17 fvdl uLong ZEXPORT adler32(adler, buf, len)
5928 1.1 paulus uLong adler;
5929 1.7 christos const Bytef *buf;
5930 1.1 paulus uInt len;
5931 1.1 paulus {
5932 1.1 paulus unsigned long s1 = adler & 0xffff;
5933 1.1 paulus unsigned long s2 = (adler >> 16) & 0xffff;
5934 1.1 paulus int k;
5935 1.1 paulus
5936 1.1 paulus if (buf == Z_NULL) return 1L;
5937 1.1 paulus
5938 1.1 paulus while (len > 0) {
5939 1.1 paulus k = len < NMAX ? len : NMAX;
5940 1.1 paulus len -= k;
5941 1.1 paulus while (k >= 16) {
5942 1.1 paulus DO16(buf);
5943 1.7 christos buf += 16;
5944 1.1 paulus k -= 16;
5945 1.1 paulus }
5946 1.1 paulus if (k != 0) do {
5947 1.7 christos s1 += *buf++;
5948 1.7 christos s2 += s1;
5949 1.1 paulus } while (--k);
5950 1.1 paulus s1 %= BASE;
5951 1.1 paulus s2 %= BASE;
5952 1.1 paulus }
5953 1.1 paulus return (s2 << 16) | s1;
5954 1.1 paulus }
5955 1.7 christos /* --- adler32.c */
5956 1.17 fvdl
5957