Commit | Line | Data |
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25f0751f | 1 | /* inflate.c -- zlib decompression |
b864a746 | 2 | * Copyright (C) 1995-2022 Mark Adler |
25f0751f PM |
3 | * For conditions of distribution and use, see copyright notice in zlib.h |
4 | */ | |
5 | ||
6 | /* | |
7 | * Change history: | |
8 | * | |
9 | * 1.2.beta0 24 Nov 2002 | |
10 | * - First version -- complete rewrite of inflate to simplify code, avoid | |
11 | * creation of window when not needed, minimize use of window when it is | |
12 | * needed, make inffast.c even faster, implement gzip decoding, and to | |
13 | * improve code readability and style over the previous zlib inflate code | |
14 | * | |
15 | * 1.2.beta1 25 Nov 2002 | |
16 | * - Use pointers for available input and output checking in inffast.c | |
17 | * - Remove input and output counters in inffast.c | |
18 | * - Change inffast.c entry and loop from avail_in >= 7 to >= 6 | |
19 | * - Remove unnecessary second byte pull from length extra in inffast.c | |
20 | * - Unroll direct copy to three copies per loop in inffast.c | |
21 | * | |
22 | * 1.2.beta2 4 Dec 2002 | |
23 | * - Change external routine names to reduce potential conflicts | |
24 | * - Correct filename to inffixed.h for fixed tables in inflate.c | |
25 | * - Make hbuf[] unsigned char to match parameter type in inflate.c | |
26 | * - Change strm->next_out[-state->offset] to *(strm->next_out - state->offset) | |
27 | * to avoid negation problem on Alphas (64 bit) in inflate.c | |
28 | * | |
29 | * 1.2.beta3 22 Dec 2002 | |
30 | * - Add comments on state->bits assertion in inffast.c | |
31 | * - Add comments on op field in inftrees.h | |
32 | * - Fix bug in reuse of allocated window after inflateReset() | |
33 | * - Remove bit fields--back to byte structure for speed | |
34 | * - Remove distance extra == 0 check in inflate_fast()--only helps for lengths | |
35 | * - Change post-increments to pre-increments in inflate_fast(), PPC biased? | |
36 | * - Add compile time option, POSTINC, to use post-increments instead (Intel?) | |
37 | * - Make MATCH copy in inflate() much faster for when inflate_fast() not used | |
38 | * - Use local copies of stream next and avail values, as well as local bit | |
39 | * buffer and bit count in inflate()--for speed when inflate_fast() not used | |
40 | * | |
41 | * 1.2.beta4 1 Jan 2003 | |
42 | * - Split ptr - 257 statements in inflate_table() to avoid compiler warnings | |
43 | * - Move a comment on output buffer sizes from inffast.c to inflate.c | |
44 | * - Add comments in inffast.c to introduce the inflate_fast() routine | |
45 | * - Rearrange window copies in inflate_fast() for speed and simplification | |
46 | * - Unroll last copy for window match in inflate_fast() | |
47 | * - Use local copies of window variables in inflate_fast() for speed | |
f02c02ec | 48 | * - Pull out common wnext == 0 case for speed in inflate_fast() |
25f0751f PM |
49 | * - Make op and len in inflate_fast() unsigned for consistency |
50 | * - Add FAR to lcode and dcode declarations in inflate_fast() | |
51 | * - Simplified bad distance check in inflate_fast() | |
52 | * - Added inflateBackInit(), inflateBack(), and inflateBackEnd() in new | |
53 | * source file infback.c to provide a call-back interface to inflate for | |
54 | * programs like gzip and unzip -- uses window as output buffer to avoid | |
55 | * window copying | |
56 | * | |
57 | * 1.2.beta5 1 Jan 2003 | |
58 | * - Improved inflateBack() interface to allow the caller to provide initial | |
59 | * input in strm. | |
60 | * - Fixed stored blocks bug in inflateBack() | |
61 | * | |
62 | * 1.2.beta6 4 Jan 2003 | |
63 | * - Added comments in inffast.c on effectiveness of POSTINC | |
64 | * - Typecasting all around to reduce compiler warnings | |
65 | * - Changed loops from while (1) or do {} while (1) to for (;;), again to | |
66 | * make compilers happy | |
67 | * - Changed type of window in inflateBackInit() to unsigned char * | |
68 | * | |
69 | * 1.2.beta7 27 Jan 2003 | |
70 | * - Changed many types to unsigned or unsigned short to avoid warnings | |
71 | * - Added inflateCopy() function | |
72 | * | |
73 | * 1.2.0 9 Mar 2003 | |
74 | * - Changed inflateBack() interface to provide separate opaque descriptors | |
75 | * for the in() and out() functions | |
76 | * - Changed inflateBack() argument and in_func typedef to swap the length | |
77 | * and buffer address return values for the input function | |
78 | * - Check next_in and next_out for Z_NULL on entry to inflate() | |
79 | * | |
80 | * The history for versions after 1.2.0 are in ChangeLog in zlib distribution. | |
81 | */ | |
82 | ||
83 | #include "zutil.h" | |
84 | #include "inftrees.h" | |
85 | #include "inflate.h" | |
86 | #include "inffast.h" | |
87 | ||
88 | #ifdef MAKEFIXED | |
89 | # ifndef BUILDFIXED | |
90 | # define BUILDFIXED | |
91 | # endif | |
92 | #endif | |
93 | ||
94 | /* function prototypes */ | |
6b93e4bc | 95 | local int inflateStateCheck OF((z_streamp strm)); |
25f0751f | 96 | local void fixedtables OF((struct inflate_state FAR *state)); |
1cae2293 CBW |
97 | local int updatewindow OF((z_streamp strm, const unsigned char FAR *end, |
98 | unsigned copy)); | |
25f0751f PM |
99 | #ifdef BUILDFIXED |
100 | void makefixed OF((void)); | |
101 | #endif | |
1cae2293 | 102 | local unsigned syncsearch OF((unsigned FAR *have, const unsigned char FAR *buf, |
25f0751f PM |
103 | unsigned len)); |
104 | ||
6b93e4bc PM |
105 | local int inflateStateCheck( |
106 | z_streamp strm) | |
107 | { | |
108 | struct inflate_state FAR *state; | |
109 | if (strm == Z_NULL || | |
110 | strm->zalloc == (alloc_func)0 || strm->zfree == (free_func)0) | |
111 | return 1; | |
112 | state = (struct inflate_state FAR *)strm->state; | |
113 | if (state == Z_NULL || state->strm != strm || | |
114 | state->mode < HEAD || state->mode > SYNC) | |
115 | return 1; | |
116 | return 0; | |
117 | } | |
118 | ||
7c8257d9 | 119 | int ZEXPORT inflateResetKeep( |
a7026383 | 120 | z_streamp strm) |
25f0751f PM |
121 | { |
122 | struct inflate_state FAR *state; | |
123 | ||
6b93e4bc | 124 | if (inflateStateCheck(strm)) return Z_STREAM_ERROR; |
25f0751f PM |
125 | state = (struct inflate_state FAR *)strm->state; |
126 | strm->total_in = strm->total_out = state->total = 0; | |
127 | strm->msg = Z_NULL; | |
7c8257d9 CBW |
128 | if (state->wrap) /* to support ill-conceived Java test suite */ |
129 | strm->adler = state->wrap & 1; | |
25f0751f PM |
130 | state->mode = HEAD; |
131 | state->last = 0; | |
132 | state->havedict = 0; | |
b864a746 | 133 | state->flags = -1; |
25f0751f PM |
134 | state->dmax = 32768U; |
135 | state->head = Z_NULL; | |
25f0751f PM |
136 | state->hold = 0; |
137 | state->bits = 0; | |
138 | state->lencode = state->distcode = state->next = state->codes; | |
f02c02ec CBW |
139 | state->sane = 1; |
140 | state->back = -1; | |
25f0751f PM |
141 | Tracev((stderr, "inflate: reset\n")); |
142 | return Z_OK; | |
143 | } | |
144 | ||
7c8257d9 CBW |
145 | int ZEXPORT inflateReset( |
146 | z_streamp strm) | |
147 | { | |
148 | struct inflate_state FAR *state; | |
149 | ||
6b93e4bc | 150 | if (inflateStateCheck(strm)) return Z_STREAM_ERROR; |
7c8257d9 CBW |
151 | state = (struct inflate_state FAR *)strm->state; |
152 | state->wsize = 0; | |
153 | state->whave = 0; | |
154 | state->wnext = 0; | |
155 | return inflateResetKeep(strm); | |
156 | } | |
157 | ||
a7026383 CBW |
158 | int ZEXPORT inflateReset2( |
159 | z_streamp strm, | |
160 | int windowBits) | |
25f0751f | 161 | { |
f02c02ec | 162 | int wrap; |
25f0751f PM |
163 | struct inflate_state FAR *state; |
164 | ||
f02c02ec | 165 | /* get the state */ |
6b93e4bc | 166 | if (inflateStateCheck(strm)) return Z_STREAM_ERROR; |
25f0751f | 167 | state = (struct inflate_state FAR *)strm->state; |
f02c02ec CBW |
168 | |
169 | /* extract wrap request from windowBits parameter */ | |
170 | if (windowBits < 0) { | |
a98bbd4e YO |
171 | if (windowBits < -15) |
172 | return Z_STREAM_ERROR; | |
f02c02ec CBW |
173 | wrap = 0; |
174 | windowBits = -windowBits; | |
175 | } | |
176 | else { | |
6b93e4bc | 177 | wrap = (windowBits >> 4) + 5; |
f02c02ec CBW |
178 | #ifdef GUNZIP |
179 | if (windowBits < 48) | |
180 | windowBits &= 15; | |
181 | #endif | |
182 | } | |
183 | ||
184 | /* set number of window bits, free window if different */ | |
185 | if (windowBits && (windowBits < 8 || windowBits > 15)) | |
186 | return Z_STREAM_ERROR; | |
187 | if (state->window != Z_NULL && state->wbits != (unsigned)windowBits) { | |
188 | ZFREE(strm, state->window); | |
189 | state->window = Z_NULL; | |
190 | } | |
191 | ||
192 | /* update state and reset the rest of it */ | |
193 | state->wrap = wrap; | |
194 | state->wbits = (unsigned)windowBits; | |
195 | return inflateReset(strm); | |
25f0751f PM |
196 | } |
197 | ||
a7026383 CBW |
198 | int ZEXPORT inflateInit2_( |
199 | z_streamp strm, | |
200 | int windowBits, | |
201 | const char *version, | |
202 | int stream_size) | |
25f0751f | 203 | { |
f02c02ec | 204 | int ret; |
25f0751f PM |
205 | struct inflate_state FAR *state; |
206 | ||
207 | if (version == Z_NULL || version[0] != ZLIB_VERSION[0] || | |
208 | stream_size != (int)(sizeof(z_stream))) | |
209 | return Z_VERSION_ERROR; | |
210 | if (strm == Z_NULL) return Z_STREAM_ERROR; | |
211 | strm->msg = Z_NULL; /* in case we return an error */ | |
212 | if (strm->zalloc == (alloc_func)0) { | |
7c8257d9 CBW |
213 | #ifdef Z_SOLO |
214 | return Z_STREAM_ERROR; | |
215 | #else | |
25f0751f PM |
216 | strm->zalloc = zcalloc; |
217 | strm->opaque = (voidpf)0; | |
7c8257d9 | 218 | #endif |
25f0751f | 219 | } |
7c8257d9 CBW |
220 | if (strm->zfree == (free_func)0) |
221 | #ifdef Z_SOLO | |
222 | return Z_STREAM_ERROR; | |
223 | #else | |
224 | strm->zfree = zcfree; | |
225 | #endif | |
25f0751f PM |
226 | state = (struct inflate_state FAR *) |
227 | ZALLOC(strm, 1, sizeof(struct inflate_state)); | |
228 | if (state == Z_NULL) return Z_MEM_ERROR; | |
229 | Tracev((stderr, "inflate: allocated\n")); | |
230 | strm->state = (struct internal_state FAR *)state; | |
6b93e4bc | 231 | state->strm = strm; |
f02c02ec | 232 | state->window = Z_NULL; |
6b93e4bc | 233 | state->mode = HEAD; /* to pass state test in inflateReset2() */ |
f02c02ec CBW |
234 | ret = inflateReset2(strm, windowBits); |
235 | if (ret != Z_OK) { | |
25f0751f PM |
236 | ZFREE(strm, state); |
237 | strm->state = Z_NULL; | |
25f0751f | 238 | } |
f02c02ec | 239 | return ret; |
25f0751f PM |
240 | } |
241 | ||
a7026383 CBW |
242 | int ZEXPORT inflateInit_( |
243 | z_streamp strm, | |
244 | const char *version, | |
245 | int stream_size) | |
25f0751f PM |
246 | { |
247 | return inflateInit2_(strm, DEF_WBITS, version, stream_size); | |
248 | } | |
249 | ||
a7026383 CBW |
250 | int ZEXPORT inflatePrime( |
251 | z_streamp strm, | |
252 | int bits, | |
253 | int value) | |
f02c02ec CBW |
254 | { |
255 | struct inflate_state FAR *state; | |
256 | ||
6b93e4bc | 257 | if (inflateStateCheck(strm)) return Z_STREAM_ERROR; |
f02c02ec CBW |
258 | state = (struct inflate_state FAR *)strm->state; |
259 | if (bits < 0) { | |
260 | state->hold = 0; | |
261 | state->bits = 0; | |
262 | return Z_OK; | |
263 | } | |
6b93e4bc | 264 | if (bits > 16 || state->bits + (uInt)bits > 32) return Z_STREAM_ERROR; |
f02c02ec | 265 | value &= (1L << bits) - 1; |
6b93e4bc PM |
266 | state->hold += (unsigned)value << state->bits; |
267 | state->bits += (uInt)bits; | |
f02c02ec CBW |
268 | return Z_OK; |
269 | } | |
270 | ||
25f0751f PM |
271 | /* |
272 | Return state with length and distance decoding tables and index sizes set to | |
273 | fixed code decoding. Normally this returns fixed tables from inffixed.h. | |
274 | If BUILDFIXED is defined, then instead this routine builds the tables the | |
275 | first time it's called, and returns those tables the first time and | |
276 | thereafter. This reduces the size of the code by about 2K bytes, in | |
277 | exchange for a little execution time. However, BUILDFIXED should not be | |
278 | used for threaded applications, since the rewriting of the tables and virgin | |
279 | may not be thread-safe. | |
280 | */ | |
a7026383 CBW |
281 | local void fixedtables( |
282 | struct inflate_state FAR *state) | |
25f0751f PM |
283 | { |
284 | #ifdef BUILDFIXED | |
285 | static int virgin = 1; | |
286 | static code *lenfix, *distfix; | |
287 | static code fixed[544]; | |
288 | ||
289 | /* build fixed huffman tables if first call (may not be thread safe) */ | |
290 | if (virgin) { | |
291 | unsigned sym, bits; | |
292 | static code *next; | |
293 | ||
294 | /* literal/length table */ | |
295 | sym = 0; | |
296 | while (sym < 144) state->lens[sym++] = 8; | |
297 | while (sym < 256) state->lens[sym++] = 9; | |
298 | while (sym < 280) state->lens[sym++] = 7; | |
299 | while (sym < 288) state->lens[sym++] = 8; | |
300 | next = fixed; | |
301 | lenfix = next; | |
302 | bits = 9; | |
303 | inflate_table(LENS, state->lens, 288, &(next), &(bits), state->work); | |
304 | ||
305 | /* distance table */ | |
306 | sym = 0; | |
307 | while (sym < 32) state->lens[sym++] = 5; | |
308 | distfix = next; | |
309 | bits = 5; | |
310 | inflate_table(DISTS, state->lens, 32, &(next), &(bits), state->work); | |
311 | ||
312 | /* do this just once */ | |
313 | virgin = 0; | |
314 | } | |
315 | #else /* !BUILDFIXED */ | |
316 | # include "inffixed.h" | |
317 | #endif /* BUILDFIXED */ | |
318 | state->lencode = lenfix; | |
319 | state->lenbits = 9; | |
320 | state->distcode = distfix; | |
321 | state->distbits = 5; | |
322 | } | |
323 | ||
324 | #ifdef MAKEFIXED | |
325 | #include <stdio.h> | |
326 | ||
327 | /* | |
328 | Write out the inffixed.h that is #include'd above. Defining MAKEFIXED also | |
329 | defines BUILDFIXED, so the tables are built on the fly. makefixed() writes | |
330 | those tables to stdout, which would be piped to inffixed.h. A small program | |
331 | can simply call makefixed to do this: | |
332 | ||
333 | void makefixed(void); | |
334 | ||
335 | int main(void) | |
336 | { | |
337 | makefixed(); | |
338 | return 0; | |
339 | } | |
340 | ||
341 | Then that can be linked with zlib built with MAKEFIXED defined and run: | |
342 | ||
343 | a.out > inffixed.h | |
344 | */ | |
345 | void makefixed() | |
346 | { | |
347 | unsigned low, size; | |
348 | struct inflate_state state; | |
349 | ||
350 | fixedtables(&state); | |
351 | puts(" /* inffixed.h -- table for decoding fixed codes"); | |
352 | puts(" * Generated automatically by makefixed()."); | |
353 | puts(" */"); | |
354 | puts(""); | |
355 | puts(" /* WARNING: this file should *not* be used by applications."); | |
356 | puts(" It is part of the implementation of this library and is"); | |
357 | puts(" subject to change. Applications should only use zlib.h."); | |
358 | puts(" */"); | |
359 | puts(""); | |
360 | size = 1U << 9; | |
361 | printf(" static const code lenfix[%u] = {", size); | |
362 | low = 0; | |
363 | for (;;) { | |
364 | if ((low % 7) == 0) printf("\n "); | |
7c8257d9 CBW |
365 | printf("{%u,%u,%d}", (low & 127) == 99 ? 64 : state.lencode[low].op, |
366 | state.lencode[low].bits, state.lencode[low].val); | |
25f0751f PM |
367 | if (++low == size) break; |
368 | putchar(','); | |
369 | } | |
370 | puts("\n };"); | |
371 | size = 1U << 5; | |
372 | printf("\n static const code distfix[%u] = {", size); | |
373 | low = 0; | |
374 | for (;;) { | |
375 | if ((low % 6) == 0) printf("\n "); | |
376 | printf("{%u,%u,%d}", state.distcode[low].op, state.distcode[low].bits, | |
377 | state.distcode[low].val); | |
378 | if (++low == size) break; | |
379 | putchar(','); | |
380 | } | |
381 | puts("\n };"); | |
382 | } | |
383 | #endif /* MAKEFIXED */ | |
384 | ||
385 | /* | |
386 | Update the window with the last wsize (normally 32K) bytes written before | |
387 | returning. If window does not exist yet, create it. This is only called | |
388 | when a window is already in use, or when output has been written during this | |
389 | inflate call, but the end of the deflate stream has not been reached yet. | |
390 | It is also called to create a window for dictionary data when a dictionary | |
391 | is loaded. | |
392 | ||
393 | Providing output buffers larger than 32K to inflate() should provide a speed | |
394 | advantage, since only the last 32K of output is copied to the sliding window | |
395 | upon return from inflate(), and since all distances after the first 32K of | |
396 | output will fall in the output data, making match copies simpler and faster. | |
397 | The advantage may be dependent on the size of the processor's data caches. | |
398 | */ | |
a7026383 CBW |
399 | local int updatewindow( |
400 | z_streamp strm, | |
1cae2293 CBW |
401 | const Bytef *end, |
402 | unsigned copy) | |
25f0751f PM |
403 | { |
404 | struct inflate_state FAR *state; | |
1cae2293 | 405 | unsigned dist; |
25f0751f PM |
406 | |
407 | state = (struct inflate_state FAR *)strm->state; | |
408 | ||
409 | /* if it hasn't been done already, allocate space for the window */ | |
410 | if (state->window == Z_NULL) { | |
411 | state->window = (unsigned char FAR *) | |
412 | ZALLOC(strm, 1U << state->wbits, | |
413 | sizeof(unsigned char)); | |
414 | if (state->window == Z_NULL) return 1; | |
415 | } | |
416 | ||
417 | /* if window not in use yet, initialize */ | |
418 | if (state->wsize == 0) { | |
419 | state->wsize = 1U << state->wbits; | |
f02c02ec | 420 | state->wnext = 0; |
25f0751f PM |
421 | state->whave = 0; |
422 | } | |
423 | ||
424 | /* copy state->wsize or less output bytes into the circular window */ | |
25f0751f | 425 | if (copy >= state->wsize) { |
1cae2293 | 426 | zmemcpy(state->window, end - state->wsize, state->wsize); |
f02c02ec | 427 | state->wnext = 0; |
25f0751f PM |
428 | state->whave = state->wsize; |
429 | } | |
430 | else { | |
f02c02ec | 431 | dist = state->wsize - state->wnext; |
25f0751f | 432 | if (dist > copy) dist = copy; |
1cae2293 | 433 | zmemcpy(state->window + state->wnext, end - copy, dist); |
25f0751f PM |
434 | copy -= dist; |
435 | if (copy) { | |
1cae2293 | 436 | zmemcpy(state->window, end - copy, copy); |
f02c02ec | 437 | state->wnext = copy; |
25f0751f PM |
438 | state->whave = state->wsize; |
439 | } | |
440 | else { | |
f02c02ec CBW |
441 | state->wnext += dist; |
442 | if (state->wnext == state->wsize) state->wnext = 0; | |
25f0751f PM |
443 | if (state->whave < state->wsize) state->whave += dist; |
444 | } | |
445 | } | |
446 | return 0; | |
447 | } | |
448 | ||
449 | /* Macros for inflate(): */ | |
450 | ||
451 | /* check function to use adler32() for zlib or crc32() for gzip */ | |
452 | #ifdef GUNZIP | |
b864a746 | 453 | # define UPDATE_CHECK(check, buf, len) \ |
25f0751f PM |
454 | (state->flags ? crc32(check, buf, len) : adler32(check, buf, len)) |
455 | #else | |
b864a746 | 456 | # define UPDATE_CHECK(check, buf, len) adler32(check, buf, len) |
25f0751f PM |
457 | #endif |
458 | ||
459 | /* check macros for header crc */ | |
460 | #ifdef GUNZIP | |
461 | # define CRC2(check, word) \ | |
462 | do { \ | |
463 | hbuf[0] = (unsigned char)(word); \ | |
464 | hbuf[1] = (unsigned char)((word) >> 8); \ | |
465 | check = crc32(check, hbuf, 2); \ | |
466 | } while (0) | |
467 | ||
468 | # define CRC4(check, word) \ | |
469 | do { \ | |
470 | hbuf[0] = (unsigned char)(word); \ | |
471 | hbuf[1] = (unsigned char)((word) >> 8); \ | |
472 | hbuf[2] = (unsigned char)((word) >> 16); \ | |
473 | hbuf[3] = (unsigned char)((word) >> 24); \ | |
474 | check = crc32(check, hbuf, 4); \ | |
475 | } while (0) | |
476 | #endif | |
477 | ||
478 | /* Load registers with state in inflate() for speed */ | |
479 | #define LOAD() \ | |
480 | do { \ | |
481 | put = strm->next_out; \ | |
482 | left = strm->avail_out; \ | |
483 | next = strm->next_in; \ | |
484 | have = strm->avail_in; \ | |
485 | hold = state->hold; \ | |
486 | bits = state->bits; \ | |
487 | } while (0) | |
488 | ||
489 | /* Restore state from registers in inflate() */ | |
490 | #define RESTORE() \ | |
491 | do { \ | |
492 | strm->next_out = put; \ | |
493 | strm->avail_out = left; \ | |
494 | strm->next_in = next; \ | |
495 | strm->avail_in = have; \ | |
496 | state->hold = hold; \ | |
497 | state->bits = bits; \ | |
498 | } while (0) | |
499 | ||
500 | /* Clear the input bit accumulator */ | |
501 | #define INITBITS() \ | |
502 | do { \ | |
503 | hold = 0; \ | |
504 | bits = 0; \ | |
505 | } while (0) | |
506 | ||
507 | /* Get a byte of input into the bit accumulator, or return from inflate() | |
508 | if there is no input available. */ | |
509 | #define PULLBYTE() \ | |
510 | do { \ | |
511 | if (have == 0) goto inf_leave; \ | |
512 | have--; \ | |
513 | hold += (unsigned long)(*next++) << bits; \ | |
514 | bits += 8; \ | |
515 | } while (0) | |
516 | ||
517 | /* Assure that there are at least n bits in the bit accumulator. If there is | |
518 | not enough available input to do that, then return from inflate(). */ | |
519 | #define NEEDBITS(n) \ | |
520 | do { \ | |
521 | while (bits < (unsigned)(n)) \ | |
522 | PULLBYTE(); \ | |
523 | } while (0) | |
524 | ||
525 | /* Return the low n bits of the bit accumulator (n < 16) */ | |
526 | #define BITS(n) \ | |
527 | ((unsigned)hold & ((1U << (n)) - 1)) | |
528 | ||
529 | /* Remove n bits from the bit accumulator */ | |
530 | #define DROPBITS(n) \ | |
531 | do { \ | |
532 | hold >>= (n); \ | |
533 | bits -= (unsigned)(n); \ | |
534 | } while (0) | |
535 | ||
536 | /* Remove zero to seven bits as needed to go to a byte boundary */ | |
537 | #define BYTEBITS() \ | |
538 | do { \ | |
539 | hold >>= bits & 7; \ | |
540 | bits -= bits & 7; \ | |
541 | } while (0) | |
542 | ||
25f0751f PM |
543 | /* |
544 | inflate() uses a state machine to process as much input data and generate as | |
545 | much output data as possible before returning. The state machine is | |
546 | structured roughly as follows: | |
547 | ||
548 | for (;;) switch (state) { | |
549 | ... | |
550 | case STATEn: | |
551 | if (not enough input data or output space to make progress) | |
552 | return; | |
553 | ... make progress ... | |
554 | state = STATEm; | |
555 | break; | |
556 | ... | |
557 | } | |
558 | ||
559 | so when inflate() is called again, the same case is attempted again, and | |
560 | if the appropriate resources are provided, the machine proceeds to the | |
561 | next state. The NEEDBITS() macro is usually the way the state evaluates | |
562 | whether it can proceed or should return. NEEDBITS() does the return if | |
563 | the requested bits are not available. The typical use of the BITS macros | |
564 | is: | |
565 | ||
566 | NEEDBITS(n); | |
567 | ... do something with BITS(n) ... | |
568 | DROPBITS(n); | |
569 | ||
570 | where NEEDBITS(n) either returns from inflate() if there isn't enough | |
571 | input left to load n bits into the accumulator, or it continues. BITS(n) | |
572 | gives the low n bits in the accumulator. When done, DROPBITS(n) drops | |
573 | the low n bits off the accumulator. INITBITS() clears the accumulator | |
574 | and sets the number of available bits to zero. BYTEBITS() discards just | |
575 | enough bits to put the accumulator on a byte boundary. After BYTEBITS() | |
576 | and a NEEDBITS(8), then BITS(8) would return the next byte in the stream. | |
577 | ||
578 | NEEDBITS(n) uses PULLBYTE() to get an available byte of input, or to return | |
579 | if there is no input available. The decoding of variable length codes uses | |
580 | PULLBYTE() directly in order to pull just enough bytes to decode the next | |
581 | code, and no more. | |
582 | ||
583 | Some states loop until they get enough input, making sure that enough | |
584 | state information is maintained to continue the loop where it left off | |
585 | if NEEDBITS() returns in the loop. For example, want, need, and keep | |
586 | would all have to actually be part of the saved state in case NEEDBITS() | |
587 | returns: | |
588 | ||
589 | case STATEw: | |
590 | while (want < need) { | |
591 | NEEDBITS(n); | |
592 | keep[want++] = BITS(n); | |
593 | DROPBITS(n); | |
594 | } | |
595 | state = STATEx; | |
596 | case STATEx: | |
597 | ||
598 | As shown above, if the next state is also the next case, then the break | |
599 | is omitted. | |
600 | ||
601 | A state may also return if there is not enough output space available to | |
602 | complete that state. Those states are copying stored data, writing a | |
603 | literal byte, and copying a matching string. | |
604 | ||
605 | When returning, a "goto inf_leave" is used to update the total counters, | |
606 | update the check value, and determine whether any progress has been made | |
607 | during that inflate() call in order to return the proper return code. | |
608 | Progress is defined as a change in either strm->avail_in or strm->avail_out. | |
609 | When there is a window, goto inf_leave will update the window with the last | |
610 | output written. If a goto inf_leave occurs in the middle of decompression | |
611 | and there is no window currently, goto inf_leave will create one and copy | |
612 | output to the window for the next call of inflate(). | |
613 | ||
614 | In this implementation, the flush parameter of inflate() only affects the | |
615 | return code (per zlib.h). inflate() always writes as much as possible to | |
616 | strm->next_out, given the space available and the provided input--the effect | |
617 | documented in zlib.h of Z_SYNC_FLUSH. Furthermore, inflate() always defers | |
618 | the allocation of and copying into a sliding window until necessary, which | |
619 | provides the effect documented in zlib.h for Z_FINISH when the entire input | |
620 | stream available. So the only thing the flush parameter actually does is: | |
621 | when flush is set to Z_FINISH, inflate() cannot return Z_OK. Instead it | |
622 | will return Z_BUF_ERROR if it has not reached the end of the stream. | |
623 | */ | |
624 | ||
a7026383 CBW |
625 | int ZEXPORT inflate( |
626 | z_streamp strm, | |
627 | int flush) | |
25f0751f PM |
628 | { |
629 | struct inflate_state FAR *state; | |
1cae2293 | 630 | z_const unsigned char FAR *next; /* next input */ |
25f0751f PM |
631 | unsigned char FAR *put; /* next output */ |
632 | unsigned have, left; /* available input and output */ | |
633 | unsigned long hold; /* bit buffer */ | |
634 | unsigned bits; /* bits in bit buffer */ | |
635 | unsigned in, out; /* save starting available input and output */ | |
636 | unsigned copy; /* number of stored or match bytes to copy */ | |
637 | unsigned char FAR *from; /* where to copy match bytes from */ | |
e224ad29 | 638 | code here; /* current decoding table entry */ |
25f0751f PM |
639 | code last; /* parent table entry */ |
640 | unsigned len; /* length to copy for repeats, bits to drop */ | |
641 | int ret; /* return code */ | |
642 | #ifdef GUNZIP | |
643 | unsigned char hbuf[4]; /* buffer for gzip header crc calculation */ | |
644 | #endif | |
645 | static const unsigned short order[19] = /* permutation of code lengths */ | |
646 | {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; | |
647 | ||
6b93e4bc | 648 | if (inflateStateCheck(strm) || strm->next_out == Z_NULL || |
25f0751f PM |
649 | (strm->next_in == Z_NULL && strm->avail_in != 0)) |
650 | return Z_STREAM_ERROR; | |
651 | ||
652 | state = (struct inflate_state FAR *)strm->state; | |
653 | if (state->mode == TYPE) state->mode = TYPEDO; /* skip check */ | |
654 | LOAD(); | |
655 | in = have; | |
656 | out = left; | |
657 | ret = Z_OK; | |
658 | for (;;) | |
659 | switch (state->mode) { | |
660 | case HEAD: | |
661 | if (state->wrap == 0) { | |
662 | state->mode = TYPEDO; | |
663 | break; | |
664 | } | |
665 | NEEDBITS(16); | |
666 | #ifdef GUNZIP | |
667 | if ((state->wrap & 2) && hold == 0x8b1f) { /* gzip header */ | |
6b93e4bc PM |
668 | if (state->wbits == 0) |
669 | state->wbits = 15; | |
25f0751f PM |
670 | state->check = crc32(0L, Z_NULL, 0); |
671 | CRC2(state->check, hold); | |
672 | INITBITS(); | |
673 | state->mode = FLAGS; | |
674 | break; | |
675 | } | |
25f0751f PM |
676 | if (state->head != Z_NULL) |
677 | state->head->done = -1; | |
678 | if (!(state->wrap & 1) || /* check if zlib header allowed */ | |
679 | #else | |
680 | if ( | |
681 | #endif | |
682 | ((BITS(8) << 8) + (hold >> 8)) % 31) { | |
683 | strm->msg = (char *)"incorrect header check"; | |
684 | state->mode = BAD; | |
685 | break; | |
686 | } | |
687 | if (BITS(4) != Z_DEFLATED) { | |
688 | strm->msg = (char *)"unknown compression method"; | |
689 | state->mode = BAD; | |
690 | break; | |
691 | } | |
692 | DROPBITS(4); | |
693 | len = BITS(4) + 8; | |
f02c02ec CBW |
694 | if (state->wbits == 0) |
695 | state->wbits = len; | |
6b93e4bc | 696 | if (len > 15 || len > state->wbits) { |
25f0751f PM |
697 | strm->msg = (char *)"invalid window size"; |
698 | state->mode = BAD; | |
699 | break; | |
700 | } | |
701 | state->dmax = 1U << len; | |
b864a746 | 702 | state->flags = 0; /* indicate zlib header */ |
25f0751f PM |
703 | Tracev((stderr, "inflate: zlib header ok\n")); |
704 | strm->adler = state->check = adler32(0L, Z_NULL, 0); | |
705 | state->mode = hold & 0x200 ? DICTID : TYPE; | |
706 | INITBITS(); | |
707 | break; | |
708 | #ifdef GUNZIP | |
709 | case FLAGS: | |
710 | NEEDBITS(16); | |
711 | state->flags = (int)(hold); | |
712 | if ((state->flags & 0xff) != Z_DEFLATED) { | |
713 | strm->msg = (char *)"unknown compression method"; | |
714 | state->mode = BAD; | |
715 | break; | |
716 | } | |
717 | if (state->flags & 0xe000) { | |
718 | strm->msg = (char *)"unknown header flags set"; | |
719 | state->mode = BAD; | |
720 | break; | |
721 | } | |
722 | if (state->head != Z_NULL) | |
723 | state->head->text = (int)((hold >> 8) & 1); | |
6b93e4bc PM |
724 | if ((state->flags & 0x0200) && (state->wrap & 4)) |
725 | CRC2(state->check, hold); | |
25f0751f PM |
726 | INITBITS(); |
727 | state->mode = TIME; | |
b864a746 | 728 | /* fallthrough */ |
25f0751f PM |
729 | case TIME: |
730 | NEEDBITS(32); | |
731 | if (state->head != Z_NULL) | |
732 | state->head->time = hold; | |
6b93e4bc PM |
733 | if ((state->flags & 0x0200) && (state->wrap & 4)) |
734 | CRC4(state->check, hold); | |
25f0751f PM |
735 | INITBITS(); |
736 | state->mode = OS; | |
b864a746 | 737 | /* fallthrough */ |
25f0751f PM |
738 | case OS: |
739 | NEEDBITS(16); | |
740 | if (state->head != Z_NULL) { | |
741 | state->head->xflags = (int)(hold & 0xff); | |
742 | state->head->os = (int)(hold >> 8); | |
743 | } | |
6b93e4bc PM |
744 | if ((state->flags & 0x0200) && (state->wrap & 4)) |
745 | CRC2(state->check, hold); | |
25f0751f PM |
746 | INITBITS(); |
747 | state->mode = EXLEN; | |
b864a746 | 748 | /* fallthrough */ |
25f0751f PM |
749 | case EXLEN: |
750 | if (state->flags & 0x0400) { | |
751 | NEEDBITS(16); | |
752 | state->length = (unsigned)(hold); | |
753 | if (state->head != Z_NULL) | |
754 | state->head->extra_len = (unsigned)hold; | |
6b93e4bc PM |
755 | if ((state->flags & 0x0200) && (state->wrap & 4)) |
756 | CRC2(state->check, hold); | |
25f0751f PM |
757 | INITBITS(); |
758 | } | |
759 | else if (state->head != Z_NULL) | |
760 | state->head->extra = Z_NULL; | |
761 | state->mode = EXTRA; | |
b864a746 | 762 | /* fallthrough */ |
25f0751f PM |
763 | case EXTRA: |
764 | if (state->flags & 0x0400) { | |
765 | copy = state->length; | |
766 | if (copy > have) copy = have; | |
767 | if (copy) { | |
768 | if (state->head != Z_NULL && | |
a98bbd4e YO |
769 | state->head->extra != Z_NULL && |
770 | (len = state->head->extra_len - state->length) < | |
771 | state->head->extra_max) { | |
25f0751f PM |
772 | zmemcpy(state->head->extra + len, next, |
773 | len + copy > state->head->extra_max ? | |
774 | state->head->extra_max - len : copy); | |
775 | } | |
6b93e4bc | 776 | if ((state->flags & 0x0200) && (state->wrap & 4)) |
25f0751f PM |
777 | state->check = crc32(state->check, next, copy); |
778 | have -= copy; | |
779 | next += copy; | |
780 | state->length -= copy; | |
781 | } | |
782 | if (state->length) goto inf_leave; | |
783 | } | |
784 | state->length = 0; | |
785 | state->mode = NAME; | |
b864a746 | 786 | /* fallthrough */ |
25f0751f PM |
787 | case NAME: |
788 | if (state->flags & 0x0800) { | |
789 | if (have == 0) goto inf_leave; | |
790 | copy = 0; | |
791 | do { | |
792 | len = (unsigned)(next[copy++]); | |
793 | if (state->head != Z_NULL && | |
794 | state->head->name != Z_NULL && | |
795 | state->length < state->head->name_max) | |
6b93e4bc | 796 | state->head->name[state->length++] = (Bytef)len; |
25f0751f | 797 | } while (len && copy < have); |
6b93e4bc | 798 | if ((state->flags & 0x0200) && (state->wrap & 4)) |
25f0751f PM |
799 | state->check = crc32(state->check, next, copy); |
800 | have -= copy; | |
801 | next += copy; | |
802 | if (len) goto inf_leave; | |
803 | } | |
804 | else if (state->head != Z_NULL) | |
805 | state->head->name = Z_NULL; | |
806 | state->length = 0; | |
807 | state->mode = COMMENT; | |
b864a746 | 808 | /* fallthrough */ |
25f0751f PM |
809 | case COMMENT: |
810 | if (state->flags & 0x1000) { | |
811 | if (have == 0) goto inf_leave; | |
812 | copy = 0; | |
813 | do { | |
814 | len = (unsigned)(next[copy++]); | |
815 | if (state->head != Z_NULL && | |
816 | state->head->comment != Z_NULL && | |
817 | state->length < state->head->comm_max) | |
6b93e4bc | 818 | state->head->comment[state->length++] = (Bytef)len; |
25f0751f | 819 | } while (len && copy < have); |
6b93e4bc | 820 | if ((state->flags & 0x0200) && (state->wrap & 4)) |
25f0751f PM |
821 | state->check = crc32(state->check, next, copy); |
822 | have -= copy; | |
823 | next += copy; | |
824 | if (len) goto inf_leave; | |
825 | } | |
826 | else if (state->head != Z_NULL) | |
827 | state->head->comment = Z_NULL; | |
828 | state->mode = HCRC; | |
b864a746 | 829 | /* fallthrough */ |
25f0751f PM |
830 | case HCRC: |
831 | if (state->flags & 0x0200) { | |
832 | NEEDBITS(16); | |
6b93e4bc | 833 | if ((state->wrap & 4) && hold != (state->check & 0xffff)) { |
25f0751f PM |
834 | strm->msg = (char *)"header crc mismatch"; |
835 | state->mode = BAD; | |
836 | break; | |
837 | } | |
838 | INITBITS(); | |
839 | } | |
840 | if (state->head != Z_NULL) { | |
841 | state->head->hcrc = (int)((state->flags >> 9) & 1); | |
842 | state->head->done = 1; | |
843 | } | |
844 | strm->adler = state->check = crc32(0L, Z_NULL, 0); | |
845 | state->mode = TYPE; | |
846 | break; | |
847 | #endif | |
848 | case DICTID: | |
849 | NEEDBITS(32); | |
7c8257d9 | 850 | strm->adler = state->check = ZSWAP32(hold); |
25f0751f PM |
851 | INITBITS(); |
852 | state->mode = DICT; | |
b864a746 | 853 | /* fallthrough */ |
25f0751f PM |
854 | case DICT: |
855 | if (state->havedict == 0) { | |
856 | RESTORE(); | |
857 | return Z_NEED_DICT; | |
858 | } | |
859 | strm->adler = state->check = adler32(0L, Z_NULL, 0); | |
860 | state->mode = TYPE; | |
b864a746 | 861 | /* fallthrough */ |
25f0751f | 862 | case TYPE: |
f02c02ec | 863 | if (flush == Z_BLOCK || flush == Z_TREES) goto inf_leave; |
b864a746 | 864 | /* fallthrough */ |
25f0751f PM |
865 | case TYPEDO: |
866 | if (state->last) { | |
867 | BYTEBITS(); | |
868 | state->mode = CHECK; | |
869 | break; | |
870 | } | |
871 | NEEDBITS(3); | |
872 | state->last = BITS(1); | |
873 | DROPBITS(1); | |
874 | switch (BITS(2)) { | |
875 | case 0: /* stored block */ | |
876 | Tracev((stderr, "inflate: stored block%s\n", | |
877 | state->last ? " (last)" : "")); | |
878 | state->mode = STORED; | |
879 | break; | |
880 | case 1: /* fixed block */ | |
881 | fixedtables(state); | |
882 | Tracev((stderr, "inflate: fixed codes block%s\n", | |
883 | state->last ? " (last)" : "")); | |
f02c02ec CBW |
884 | state->mode = LEN_; /* decode codes */ |
885 | if (flush == Z_TREES) { | |
886 | DROPBITS(2); | |
887 | goto inf_leave; | |
888 | } | |
25f0751f PM |
889 | break; |
890 | case 2: /* dynamic block */ | |
891 | Tracev((stderr, "inflate: dynamic codes block%s\n", | |
892 | state->last ? " (last)" : "")); | |
893 | state->mode = TABLE; | |
894 | break; | |
895 | case 3: | |
896 | strm->msg = (char *)"invalid block type"; | |
897 | state->mode = BAD; | |
898 | } | |
899 | DROPBITS(2); | |
900 | break; | |
901 | case STORED: | |
902 | BYTEBITS(); /* go to byte boundary */ | |
903 | NEEDBITS(32); | |
904 | if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) { | |
905 | strm->msg = (char *)"invalid stored block lengths"; | |
906 | state->mode = BAD; | |
907 | break; | |
908 | } | |
909 | state->length = (unsigned)hold & 0xffff; | |
910 | Tracev((stderr, "inflate: stored length %u\n", | |
911 | state->length)); | |
912 | INITBITS(); | |
f02c02ec CBW |
913 | state->mode = COPY_; |
914 | if (flush == Z_TREES) goto inf_leave; | |
b864a746 | 915 | /* fallthrough */ |
f02c02ec | 916 | case COPY_: |
25f0751f | 917 | state->mode = COPY; |
b864a746 | 918 | /* fallthrough */ |
25f0751f PM |
919 | case COPY: |
920 | copy = state->length; | |
921 | if (copy) { | |
922 | if (copy > have) copy = have; | |
923 | if (copy > left) copy = left; | |
924 | if (copy == 0) goto inf_leave; | |
925 | zmemcpy(put, next, copy); | |
926 | have -= copy; | |
927 | next += copy; | |
928 | left -= copy; | |
929 | put += copy; | |
930 | state->length -= copy; | |
931 | break; | |
932 | } | |
933 | Tracev((stderr, "inflate: stored end\n")); | |
934 | state->mode = TYPE; | |
935 | break; | |
936 | case TABLE: | |
937 | NEEDBITS(14); | |
938 | state->nlen = BITS(5) + 257; | |
939 | DROPBITS(5); | |
940 | state->ndist = BITS(5) + 1; | |
941 | DROPBITS(5); | |
942 | state->ncode = BITS(4) + 4; | |
943 | DROPBITS(4); | |
944 | #ifndef PKZIP_BUG_WORKAROUND | |
945 | if (state->nlen > 286 || state->ndist > 30) { | |
946 | strm->msg = (char *)"too many length or distance symbols"; | |
947 | state->mode = BAD; | |
948 | break; | |
949 | } | |
950 | #endif | |
951 | Tracev((stderr, "inflate: table sizes ok\n")); | |
952 | state->have = 0; | |
953 | state->mode = LENLENS; | |
b864a746 | 954 | /* fallthrough */ |
25f0751f PM |
955 | case LENLENS: |
956 | while (state->have < state->ncode) { | |
957 | NEEDBITS(3); | |
958 | state->lens[order[state->have++]] = (unsigned short)BITS(3); | |
959 | DROPBITS(3); | |
960 | } | |
961 | while (state->have < 19) | |
962 | state->lens[order[state->have++]] = 0; | |
963 | state->next = state->codes; | |
1cae2293 | 964 | state->lencode = (const code FAR *)(state->next); |
25f0751f PM |
965 | state->lenbits = 7; |
966 | ret = inflate_table(CODES, state->lens, 19, &(state->next), | |
967 | &(state->lenbits), state->work); | |
968 | if (ret) { | |
969 | strm->msg = (char *)"invalid code lengths set"; | |
970 | state->mode = BAD; | |
971 | break; | |
972 | } | |
973 | Tracev((stderr, "inflate: code lengths ok\n")); | |
974 | state->have = 0; | |
975 | state->mode = CODELENS; | |
b864a746 | 976 | /* fallthrough */ |
25f0751f PM |
977 | case CODELENS: |
978 | while (state->have < state->nlen + state->ndist) { | |
979 | for (;;) { | |
e224ad29 PM |
980 | here = state->lencode[BITS(state->lenbits)]; |
981 | if ((unsigned)(here.bits) <= bits) break; | |
25f0751f PM |
982 | PULLBYTE(); |
983 | } | |
e224ad29 | 984 | if (here.val < 16) { |
e224ad29 PM |
985 | DROPBITS(here.bits); |
986 | state->lens[state->have++] = here.val; | |
25f0751f PM |
987 | } |
988 | else { | |
e224ad29 PM |
989 | if (here.val == 16) { |
990 | NEEDBITS(here.bits + 2); | |
991 | DROPBITS(here.bits); | |
25f0751f PM |
992 | if (state->have == 0) { |
993 | strm->msg = (char *)"invalid bit length repeat"; | |
994 | state->mode = BAD; | |
995 | break; | |
996 | } | |
997 | len = state->lens[state->have - 1]; | |
998 | copy = 3 + BITS(2); | |
999 | DROPBITS(2); | |
1000 | } | |
e224ad29 PM |
1001 | else if (here.val == 17) { |
1002 | NEEDBITS(here.bits + 3); | |
1003 | DROPBITS(here.bits); | |
25f0751f PM |
1004 | len = 0; |
1005 | copy = 3 + BITS(3); | |
1006 | DROPBITS(3); | |
1007 | } | |
1008 | else { | |
e224ad29 PM |
1009 | NEEDBITS(here.bits + 7); |
1010 | DROPBITS(here.bits); | |
25f0751f PM |
1011 | len = 0; |
1012 | copy = 11 + BITS(7); | |
1013 | DROPBITS(7); | |
1014 | } | |
1015 | if (state->have + copy > state->nlen + state->ndist) { | |
1016 | strm->msg = (char *)"invalid bit length repeat"; | |
1017 | state->mode = BAD; | |
1018 | break; | |
1019 | } | |
1020 | while (copy--) | |
1021 | state->lens[state->have++] = (unsigned short)len; | |
1022 | } | |
1023 | } | |
1024 | ||
1025 | /* handle error breaks in while */ | |
1026 | if (state->mode == BAD) break; | |
1027 | ||
f02c02ec CBW |
1028 | /* check for end-of-block code (better have one) */ |
1029 | if (state->lens[256] == 0) { | |
1030 | strm->msg = (char *)"invalid code -- missing end-of-block"; | |
1031 | state->mode = BAD; | |
1032 | break; | |
1033 | } | |
1034 | ||
1035 | /* build code tables -- note: do not change the lenbits or distbits | |
1036 | values here (9 and 6) without reading the comments in inftrees.h | |
1037 | concerning the ENOUGH constants, which depend on those values */ | |
25f0751f | 1038 | state->next = state->codes; |
1cae2293 | 1039 | state->lencode = (const code FAR *)(state->next); |
25f0751f PM |
1040 | state->lenbits = 9; |
1041 | ret = inflate_table(LENS, state->lens, state->nlen, &(state->next), | |
1042 | &(state->lenbits), state->work); | |
1043 | if (ret) { | |
1044 | strm->msg = (char *)"invalid literal/lengths set"; | |
1045 | state->mode = BAD; | |
1046 | break; | |
1047 | } | |
1cae2293 | 1048 | state->distcode = (const code FAR *)(state->next); |
25f0751f PM |
1049 | state->distbits = 6; |
1050 | ret = inflate_table(DISTS, state->lens + state->nlen, state->ndist, | |
1051 | &(state->next), &(state->distbits), state->work); | |
1052 | if (ret) { | |
1053 | strm->msg = (char *)"invalid distances set"; | |
1054 | state->mode = BAD; | |
1055 | break; | |
1056 | } | |
1057 | Tracev((stderr, "inflate: codes ok\n")); | |
f02c02ec CBW |
1058 | state->mode = LEN_; |
1059 | if (flush == Z_TREES) goto inf_leave; | |
b864a746 | 1060 | /* fallthrough */ |
f02c02ec | 1061 | case LEN_: |
25f0751f | 1062 | state->mode = LEN; |
b864a746 | 1063 | /* fallthrough */ |
25f0751f PM |
1064 | case LEN: |
1065 | if (have >= 6 && left >= 258) { | |
1066 | RESTORE(); | |
1067 | inflate_fast(strm, out); | |
1068 | LOAD(); | |
f02c02ec CBW |
1069 | if (state->mode == TYPE) |
1070 | state->back = -1; | |
25f0751f PM |
1071 | break; |
1072 | } | |
f02c02ec | 1073 | state->back = 0; |
25f0751f | 1074 | for (;;) { |
e224ad29 PM |
1075 | here = state->lencode[BITS(state->lenbits)]; |
1076 | if ((unsigned)(here.bits) <= bits) break; | |
25f0751f PM |
1077 | PULLBYTE(); |
1078 | } | |
e224ad29 PM |
1079 | if (here.op && (here.op & 0xf0) == 0) { |
1080 | last = here; | |
25f0751f | 1081 | for (;;) { |
e224ad29 | 1082 | here = state->lencode[last.val + |
25f0751f | 1083 | (BITS(last.bits + last.op) >> last.bits)]; |
e224ad29 | 1084 | if ((unsigned)(last.bits + here.bits) <= bits) break; |
25f0751f PM |
1085 | PULLBYTE(); |
1086 | } | |
1087 | DROPBITS(last.bits); | |
f02c02ec | 1088 | state->back += last.bits; |
25f0751f | 1089 | } |
e224ad29 | 1090 | DROPBITS(here.bits); |
f02c02ec | 1091 | state->back += here.bits; |
e224ad29 PM |
1092 | state->length = (unsigned)here.val; |
1093 | if ((int)(here.op) == 0) { | |
1094 | Tracevv((stderr, here.val >= 0x20 && here.val < 0x7f ? | |
25f0751f | 1095 | "inflate: literal '%c'\n" : |
e224ad29 | 1096 | "inflate: literal 0x%02x\n", here.val)); |
25f0751f PM |
1097 | state->mode = LIT; |
1098 | break; | |
1099 | } | |
e224ad29 | 1100 | if (here.op & 32) { |
25f0751f | 1101 | Tracevv((stderr, "inflate: end of block\n")); |
f02c02ec | 1102 | state->back = -1; |
25f0751f PM |
1103 | state->mode = TYPE; |
1104 | break; | |
1105 | } | |
e224ad29 | 1106 | if (here.op & 64) { |
25f0751f PM |
1107 | strm->msg = (char *)"invalid literal/length code"; |
1108 | state->mode = BAD; | |
1109 | break; | |
1110 | } | |
e224ad29 | 1111 | state->extra = (unsigned)(here.op) & 15; |
25f0751f | 1112 | state->mode = LENEXT; |
b864a746 | 1113 | /* fallthrough */ |
25f0751f PM |
1114 | case LENEXT: |
1115 | if (state->extra) { | |
1116 | NEEDBITS(state->extra); | |
1117 | state->length += BITS(state->extra); | |
1118 | DROPBITS(state->extra); | |
f02c02ec | 1119 | state->back += state->extra; |
25f0751f PM |
1120 | } |
1121 | Tracevv((stderr, "inflate: length %u\n", state->length)); | |
f02c02ec | 1122 | state->was = state->length; |
25f0751f | 1123 | state->mode = DIST; |
b864a746 | 1124 | /* fallthrough */ |
25f0751f PM |
1125 | case DIST: |
1126 | for (;;) { | |
e224ad29 PM |
1127 | here = state->distcode[BITS(state->distbits)]; |
1128 | if ((unsigned)(here.bits) <= bits) break; | |
25f0751f PM |
1129 | PULLBYTE(); |
1130 | } | |
e224ad29 PM |
1131 | if ((here.op & 0xf0) == 0) { |
1132 | last = here; | |
25f0751f | 1133 | for (;;) { |
e224ad29 | 1134 | here = state->distcode[last.val + |
25f0751f | 1135 | (BITS(last.bits + last.op) >> last.bits)]; |
e224ad29 | 1136 | if ((unsigned)(last.bits + here.bits) <= bits) break; |
25f0751f PM |
1137 | PULLBYTE(); |
1138 | } | |
1139 | DROPBITS(last.bits); | |
f02c02ec | 1140 | state->back += last.bits; |
25f0751f | 1141 | } |
e224ad29 | 1142 | DROPBITS(here.bits); |
f02c02ec | 1143 | state->back += here.bits; |
e224ad29 | 1144 | if (here.op & 64) { |
25f0751f PM |
1145 | strm->msg = (char *)"invalid distance code"; |
1146 | state->mode = BAD; | |
1147 | break; | |
1148 | } | |
e224ad29 PM |
1149 | state->offset = (unsigned)here.val; |
1150 | state->extra = (unsigned)(here.op) & 15; | |
25f0751f | 1151 | state->mode = DISTEXT; |
b864a746 | 1152 | /* fallthrough */ |
25f0751f PM |
1153 | case DISTEXT: |
1154 | if (state->extra) { | |
1155 | NEEDBITS(state->extra); | |
1156 | state->offset += BITS(state->extra); | |
1157 | DROPBITS(state->extra); | |
f02c02ec | 1158 | state->back += state->extra; |
25f0751f PM |
1159 | } |
1160 | #ifdef INFLATE_STRICT | |
1161 | if (state->offset > state->dmax) { | |
1162 | strm->msg = (char *)"invalid distance too far back"; | |
1163 | state->mode = BAD; | |
1164 | break; | |
1165 | } | |
1166 | #endif | |
25f0751f PM |
1167 | Tracevv((stderr, "inflate: distance %u\n", state->offset)); |
1168 | state->mode = MATCH; | |
b864a746 | 1169 | /* fallthrough */ |
25f0751f PM |
1170 | case MATCH: |
1171 | if (left == 0) goto inf_leave; | |
1172 | copy = out - left; | |
1173 | if (state->offset > copy) { /* copy from window */ | |
1174 | copy = state->offset - copy; | |
f02c02ec CBW |
1175 | if (copy > state->whave) { |
1176 | if (state->sane) { | |
1177 | strm->msg = (char *)"invalid distance too far back"; | |
1178 | state->mode = BAD; | |
1179 | break; | |
1180 | } | |
1181 | #ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR | |
1182 | Trace((stderr, "inflate.c too far\n")); | |
1183 | copy -= state->whave; | |
1184 | if (copy > state->length) copy = state->length; | |
1185 | if (copy > left) copy = left; | |
1186 | left -= copy; | |
1187 | state->length -= copy; | |
1188 | do { | |
1189 | *put++ = 0; | |
1190 | } while (--copy); | |
1191 | if (state->length == 0) state->mode = LEN; | |
1192 | break; | |
1193 | #endif | |
1194 | } | |
1195 | if (copy > state->wnext) { | |
1196 | copy -= state->wnext; | |
25f0751f PM |
1197 | from = state->window + (state->wsize - copy); |
1198 | } | |
1199 | else | |
f02c02ec | 1200 | from = state->window + (state->wnext - copy); |
25f0751f PM |
1201 | if (copy > state->length) copy = state->length; |
1202 | } | |
1203 | else { /* copy from output */ | |
1204 | from = put - state->offset; | |
1205 | copy = state->length; | |
1206 | } | |
1207 | if (copy > left) copy = left; | |
1208 | left -= copy; | |
1209 | state->length -= copy; | |
1210 | do { | |
1211 | *put++ = *from++; | |
1212 | } while (--copy); | |
1213 | if (state->length == 0) state->mode = LEN; | |
1214 | break; | |
1215 | case LIT: | |
1216 | if (left == 0) goto inf_leave; | |
1217 | *put++ = (unsigned char)(state->length); | |
1218 | left--; | |
1219 | state->mode = LEN; | |
1220 | break; | |
1221 | case CHECK: | |
1222 | if (state->wrap) { | |
1223 | NEEDBITS(32); | |
1224 | out -= left; | |
1225 | strm->total_out += out; | |
1226 | state->total += out; | |
6b93e4bc | 1227 | if ((state->wrap & 4) && out) |
25f0751f | 1228 | strm->adler = state->check = |
b864a746 | 1229 | UPDATE_CHECK(state->check, put - out, out); |
25f0751f | 1230 | out = left; |
6b93e4bc | 1231 | if ((state->wrap & 4) && ( |
25f0751f PM |
1232 | #ifdef GUNZIP |
1233 | state->flags ? hold : | |
1234 | #endif | |
7c8257d9 | 1235 | ZSWAP32(hold)) != state->check) { |
25f0751f PM |
1236 | strm->msg = (char *)"incorrect data check"; |
1237 | state->mode = BAD; | |
1238 | break; | |
1239 | } | |
1240 | INITBITS(); | |
1241 | Tracev((stderr, "inflate: check matches trailer\n")); | |
1242 | } | |
1243 | #ifdef GUNZIP | |
1244 | state->mode = LENGTH; | |
b864a746 | 1245 | /* fallthrough */ |
25f0751f PM |
1246 | case LENGTH: |
1247 | if (state->wrap && state->flags) { | |
1248 | NEEDBITS(32); | |
b864a746 | 1249 | if ((state->wrap & 4) && hold != (state->total & 0xffffffff)) { |
25f0751f PM |
1250 | strm->msg = (char *)"incorrect length check"; |
1251 | state->mode = BAD; | |
1252 | break; | |
1253 | } | |
1254 | INITBITS(); | |
1255 | Tracev((stderr, "inflate: length matches trailer\n")); | |
1256 | } | |
1257 | #endif | |
1258 | state->mode = DONE; | |
b864a746 | 1259 | /* fallthrough */ |
25f0751f PM |
1260 | case DONE: |
1261 | ret = Z_STREAM_END; | |
1262 | goto inf_leave; | |
1263 | case BAD: | |
1264 | ret = Z_DATA_ERROR; | |
1265 | goto inf_leave; | |
1266 | case MEM: | |
1267 | return Z_MEM_ERROR; | |
1268 | case SYNC: | |
b864a746 | 1269 | /* fallthrough */ |
25f0751f PM |
1270 | default: |
1271 | return Z_STREAM_ERROR; | |
1272 | } | |
1273 | ||
1274 | /* | |
1275 | Return from inflate(), updating the total counts and the check value. | |
1276 | If there was no progress during the inflate() call, return a buffer | |
1277 | error. Call updatewindow() to create and/or update the window state. | |
1278 | Note: a memory error from inflate() is non-recoverable. | |
1279 | */ | |
1280 | inf_leave: | |
1281 | RESTORE(); | |
7c8257d9 CBW |
1282 | if (state->wsize || (out != strm->avail_out && state->mode < BAD && |
1283 | (state->mode < CHECK || flush != Z_FINISH))) | |
1cae2293 | 1284 | if (updatewindow(strm, strm->next_out, out - strm->avail_out)) { |
25f0751f PM |
1285 | state->mode = MEM; |
1286 | return Z_MEM_ERROR; | |
1287 | } | |
1288 | in -= strm->avail_in; | |
1289 | out -= strm->avail_out; | |
1290 | strm->total_in += in; | |
1291 | strm->total_out += out; | |
1292 | state->total += out; | |
6b93e4bc | 1293 | if ((state->wrap & 4) && out) |
25f0751f | 1294 | strm->adler = state->check = |
b864a746 | 1295 | UPDATE_CHECK(state->check, strm->next_out - out, out); |
6b93e4bc | 1296 | strm->data_type = (int)state->bits + (state->last ? 64 : 0) + |
f02c02ec CBW |
1297 | (state->mode == TYPE ? 128 : 0) + |
1298 | (state->mode == LEN_ || state->mode == COPY_ ? 256 : 0); | |
25f0751f PM |
1299 | if (((in == 0 && out == 0) || flush == Z_FINISH) && ret == Z_OK) |
1300 | ret = Z_BUF_ERROR; | |
1301 | return ret; | |
1302 | } | |
1303 | ||
a7026383 CBW |
1304 | int ZEXPORT inflateEnd( |
1305 | z_streamp strm) | |
25f0751f PM |
1306 | { |
1307 | struct inflate_state FAR *state; | |
6b93e4bc | 1308 | if (inflateStateCheck(strm)) |
25f0751f PM |
1309 | return Z_STREAM_ERROR; |
1310 | state = (struct inflate_state FAR *)strm->state; | |
1311 | if (state->window != Z_NULL) ZFREE(strm, state->window); | |
1312 | ZFREE(strm, strm->state); | |
1313 | strm->state = Z_NULL; | |
1314 | Tracev((stderr, "inflate: end\n")); | |
1315 | return Z_OK; | |
1316 | } | |
1317 | ||
1cae2293 CBW |
1318 | int ZEXPORT inflateGetDictionary( |
1319 | z_streamp strm, | |
1320 | Bytef *dictionary, | |
1321 | uInt *dictLength) | |
1322 | { | |
1323 | struct inflate_state FAR *state; | |
1324 | ||
1325 | /* check state */ | |
6b93e4bc | 1326 | if (inflateStateCheck(strm)) return Z_STREAM_ERROR; |
1cae2293 CBW |
1327 | state = (struct inflate_state FAR *)strm->state; |
1328 | ||
1329 | /* copy dictionary */ | |
1330 | if (state->whave && dictionary != Z_NULL) { | |
1331 | zmemcpy(dictionary, state->window + state->wnext, | |
1332 | state->whave - state->wnext); | |
1333 | zmemcpy(dictionary + state->whave - state->wnext, | |
1334 | state->window, state->wnext); | |
1335 | } | |
1336 | if (dictLength != Z_NULL) | |
1337 | *dictLength = state->whave; | |
1338 | return Z_OK; | |
1339 | } | |
1340 | ||
a7026383 CBW |
1341 | int ZEXPORT inflateSetDictionary( |
1342 | z_streamp strm, | |
1343 | const Bytef *dictionary, | |
1344 | uInt dictLength) | |
25f0751f PM |
1345 | { |
1346 | struct inflate_state FAR *state; | |
7c8257d9 | 1347 | unsigned long dictid; |
7c8257d9 | 1348 | int ret; |
25f0751f PM |
1349 | |
1350 | /* check state */ | |
6b93e4bc | 1351 | if (inflateStateCheck(strm)) return Z_STREAM_ERROR; |
25f0751f PM |
1352 | state = (struct inflate_state FAR *)strm->state; |
1353 | if (state->wrap != 0 && state->mode != DICT) | |
1354 | return Z_STREAM_ERROR; | |
1355 | ||
7c8257d9 | 1356 | /* check for correct dictionary identifier */ |
25f0751f | 1357 | if (state->mode == DICT) { |
7c8257d9 CBW |
1358 | dictid = adler32(0L, Z_NULL, 0); |
1359 | dictid = adler32(dictid, dictionary, dictLength); | |
1360 | if (dictid != state->check) | |
25f0751f PM |
1361 | return Z_DATA_ERROR; |
1362 | } | |
1363 | ||
7c8257d9 CBW |
1364 | /* copy dictionary to window using updatewindow(), which will amend the |
1365 | existing dictionary if appropriate */ | |
1cae2293 | 1366 | ret = updatewindow(strm, dictionary + dictLength, dictLength); |
7c8257d9 | 1367 | if (ret) { |
25f0751f PM |
1368 | state->mode = MEM; |
1369 | return Z_MEM_ERROR; | |
1370 | } | |
25f0751f PM |
1371 | state->havedict = 1; |
1372 | Tracev((stderr, "inflate: dictionary set\n")); | |
1373 | return Z_OK; | |
1374 | } | |
1375 | ||
a7026383 CBW |
1376 | int ZEXPORT inflateGetHeader( |
1377 | z_streamp strm, | |
1378 | gz_headerp head) | |
25f0751f PM |
1379 | { |
1380 | struct inflate_state FAR *state; | |
1381 | ||
1382 | /* check state */ | |
6b93e4bc | 1383 | if (inflateStateCheck(strm)) return Z_STREAM_ERROR; |
25f0751f PM |
1384 | state = (struct inflate_state FAR *)strm->state; |
1385 | if ((state->wrap & 2) == 0) return Z_STREAM_ERROR; | |
1386 | ||
1387 | /* save header structure */ | |
1388 | state->head = head; | |
1389 | head->done = 0; | |
1390 | return Z_OK; | |
1391 | } | |
1392 | ||
1393 | /* | |
1394 | Search buf[0..len-1] for the pattern: 0, 0, 0xff, 0xff. Return when found | |
1395 | or when out of input. When called, *have is the number of pattern bytes | |
1396 | found in order so far, in 0..3. On return *have is updated to the new | |
1397 | state. If on return *have equals four, then the pattern was found and the | |
1398 | return value is how many bytes were read including the last byte of the | |
1399 | pattern. If *have is less than four, then the pattern has not been found | |
1400 | yet and the return value is len. In the latter case, syncsearch() can be | |
1401 | called again with more data and the *have state. *have is initialized to | |
1402 | zero for the first call. | |
1403 | */ | |
a7026383 CBW |
1404 | local unsigned syncsearch( |
1405 | unsigned FAR *have, | |
1cae2293 | 1406 | const unsigned char FAR *buf, |
a7026383 | 1407 | unsigned len) |
25f0751f PM |
1408 | { |
1409 | unsigned got; | |
1410 | unsigned next; | |
1411 | ||
1412 | got = *have; | |
1413 | next = 0; | |
1414 | while (next < len && got < 4) { | |
1415 | if ((int)(buf[next]) == (got < 2 ? 0 : 0xff)) | |
1416 | got++; | |
1417 | else if (buf[next]) | |
1418 | got = 0; | |
1419 | else | |
1420 | got = 4 - got; | |
1421 | next++; | |
1422 | } | |
1423 | *have = got; | |
1424 | return next; | |
1425 | } | |
1426 | ||
a7026383 CBW |
1427 | int ZEXPORT inflateSync( |
1428 | z_streamp strm) | |
25f0751f PM |
1429 | { |
1430 | unsigned len; /* number of bytes to look at or looked at */ | |
b864a746 | 1431 | int flags; /* temporary to save header status */ |
25f0751f PM |
1432 | unsigned long in, out; /* temporary to save total_in and total_out */ |
1433 | unsigned char buf[4]; /* to restore bit buffer to byte string */ | |
1434 | struct inflate_state FAR *state; | |
1435 | ||
1436 | /* check parameters */ | |
6b93e4bc | 1437 | if (inflateStateCheck(strm)) return Z_STREAM_ERROR; |
25f0751f PM |
1438 | state = (struct inflate_state FAR *)strm->state; |
1439 | if (strm->avail_in == 0 && state->bits < 8) return Z_BUF_ERROR; | |
1440 | ||
1441 | /* if first time, start search in bit buffer */ | |
1442 | if (state->mode != SYNC) { | |
1443 | state->mode = SYNC; | |
1444 | state->hold <<= state->bits & 7; | |
1445 | state->bits -= state->bits & 7; | |
1446 | len = 0; | |
1447 | while (state->bits >= 8) { | |
1448 | buf[len++] = (unsigned char)(state->hold); | |
1449 | state->hold >>= 8; | |
1450 | state->bits -= 8; | |
1451 | } | |
1452 | state->have = 0; | |
1453 | syncsearch(&(state->have), buf, len); | |
1454 | } | |
1455 | ||
1456 | /* search available input */ | |
1457 | len = syncsearch(&(state->have), strm->next_in, strm->avail_in); | |
1458 | strm->avail_in -= len; | |
1459 | strm->next_in += len; | |
1460 | strm->total_in += len; | |
1461 | ||
1462 | /* return no joy or set up to restart inflate() on a new block */ | |
1463 | if (state->have != 4) return Z_DATA_ERROR; | |
b864a746 PM |
1464 | if (state->flags == -1) |
1465 | state->wrap = 0; /* if no header yet, treat as raw */ | |
1466 | else | |
1467 | state->wrap &= ~4; /* no point in computing a check value now */ | |
1468 | flags = state->flags; | |
25f0751f PM |
1469 | in = strm->total_in; out = strm->total_out; |
1470 | inflateReset(strm); | |
1471 | strm->total_in = in; strm->total_out = out; | |
b864a746 | 1472 | state->flags = flags; |
25f0751f PM |
1473 | state->mode = TYPE; |
1474 | return Z_OK; | |
1475 | } | |
1476 | ||
1477 | /* | |
1478 | Returns true if inflate is currently at the end of a block generated by | |
1479 | Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP | |
1480 | implementation to provide an additional safety check. PPP uses | |
1481 | Z_SYNC_FLUSH but removes the length bytes of the resulting empty stored | |
1482 | block. When decompressing, PPP checks that at the end of input packet, | |
1483 | inflate is waiting for these length bytes. | |
1484 | */ | |
a7026383 CBW |
1485 | int ZEXPORT inflateSyncPoint( |
1486 | z_streamp strm) | |
25f0751f PM |
1487 | { |
1488 | struct inflate_state FAR *state; | |
1489 | ||
6b93e4bc | 1490 | if (inflateStateCheck(strm)) return Z_STREAM_ERROR; |
25f0751f PM |
1491 | state = (struct inflate_state FAR *)strm->state; |
1492 | return state->mode == STORED && state->bits == 0; | |
1493 | } | |
1494 | ||
a7026383 CBW |
1495 | int ZEXPORT inflateCopy( |
1496 | z_streamp dest, | |
1497 | z_streamp source) | |
25f0751f PM |
1498 | { |
1499 | struct inflate_state FAR *state; | |
1500 | struct inflate_state FAR *copy; | |
1501 | unsigned char FAR *window; | |
1502 | unsigned wsize; | |
1503 | ||
1504 | /* check input */ | |
6b93e4bc | 1505 | if (inflateStateCheck(source) || dest == Z_NULL) |
25f0751f PM |
1506 | return Z_STREAM_ERROR; |
1507 | state = (struct inflate_state FAR *)source->state; | |
1508 | ||
1509 | /* allocate space */ | |
1510 | copy = (struct inflate_state FAR *) | |
1511 | ZALLOC(source, 1, sizeof(struct inflate_state)); | |
1512 | if (copy == Z_NULL) return Z_MEM_ERROR; | |
1513 | window = Z_NULL; | |
1514 | if (state->window != Z_NULL) { | |
1515 | window = (unsigned char FAR *) | |
1516 | ZALLOC(source, 1U << state->wbits, sizeof(unsigned char)); | |
1517 | if (window == Z_NULL) { | |
1518 | ZFREE(source, copy); | |
1519 | return Z_MEM_ERROR; | |
1520 | } | |
1521 | } | |
1522 | ||
1523 | /* copy state */ | |
7c8257d9 CBW |
1524 | zmemcpy((Bytef*)dest, (Bytef*)source, sizeof(z_stream)); |
1525 | zmemcpy((Bytef*)copy, (Bytef*)state, sizeof(struct inflate_state)); | |
6b93e4bc | 1526 | copy->strm = dest; |
25f0751f PM |
1527 | if (state->lencode >= state->codes && |
1528 | state->lencode <= state->codes + ENOUGH - 1) { | |
1529 | copy->lencode = copy->codes + (state->lencode - state->codes); | |
1530 | copy->distcode = copy->codes + (state->distcode - state->codes); | |
1531 | } | |
1532 | copy->next = copy->codes + (state->next - state->codes); | |
1533 | if (window != Z_NULL) { | |
1534 | wsize = 1U << state->wbits; | |
1535 | zmemcpy(window, state->window, wsize); | |
1536 | } | |
1537 | copy->window = window; | |
1538 | dest->state = (struct internal_state FAR *)copy; | |
1539 | return Z_OK; | |
1540 | } | |
f02c02ec | 1541 | |
a7026383 CBW |
1542 | int ZEXPORT inflateUndermine( |
1543 | z_streamp strm, | |
1544 | int subvert) | |
f02c02ec CBW |
1545 | { |
1546 | struct inflate_state FAR *state; | |
1547 | ||
6b93e4bc | 1548 | if (inflateStateCheck(strm)) return Z_STREAM_ERROR; |
f02c02ec | 1549 | state = (struct inflate_state FAR *)strm->state; |
9d990278 | 1550 | #ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR |
70a3f1a0 | 1551 | state->sane = !subvert; |
f02c02ec CBW |
1552 | return Z_OK; |
1553 | #else | |
70a3f1a0 | 1554 | (void)subvert; |
f02c02ec CBW |
1555 | state->sane = 1; |
1556 | return Z_DATA_ERROR; | |
1557 | #endif | |
1558 | } | |
1559 | ||
6b93e4bc PM |
1560 | int ZEXPORT inflateValidate( |
1561 | z_streamp strm, | |
1562 | int check) | |
1563 | { | |
1564 | struct inflate_state FAR *state; | |
1565 | ||
1566 | if (inflateStateCheck(strm)) return Z_STREAM_ERROR; | |
1567 | state = (struct inflate_state FAR *)strm->state; | |
b864a746 | 1568 | if (check && state->wrap) |
6b93e4bc PM |
1569 | state->wrap |= 4; |
1570 | else | |
1571 | state->wrap &= ~4; | |
1572 | return Z_OK; | |
1573 | } | |
1574 | ||
a7026383 CBW |
1575 | long ZEXPORT inflateMark( |
1576 | z_streamp strm) | |
f02c02ec CBW |
1577 | { |
1578 | struct inflate_state FAR *state; | |
1579 | ||
6b93e4bc | 1580 | if (inflateStateCheck(strm)) |
70a3f1a0 | 1581 | return -(1L << 16); |
f02c02ec | 1582 | state = (struct inflate_state FAR *)strm->state; |
6b93e4bc | 1583 | return (long)(((unsigned long)((long)state->back)) << 16) + |
f02c02ec CBW |
1584 | (state->mode == COPY ? state->length : |
1585 | (state->mode == MATCH ? state->was - state->length : 0)); | |
1586 | } | |
6b93e4bc PM |
1587 | |
1588 | unsigned long ZEXPORT inflateCodesUsed( | |
1589 | z_streamp strm) | |
1590 | { | |
1591 | struct inflate_state FAR *state; | |
1592 | if (inflateStateCheck(strm)) return (unsigned long)-1; | |
1593 | state = (struct inflate_state FAR *)strm->state; | |
1594 | return (unsigned long)(state->next - state->codes); | |
1595 | } |