Line data Source code
1 : /* $OpenBSD: inflate.c,v 1.14 2016/03/23 19:39:48 natano Exp $ */
2 : /* inflate.c -- zlib decompression
3 : * Copyright (C) 1995-2005 Mark Adler
4 : * For conditions of distribution and use, see copyright notice in zlib.h
5 : */
6 :
7 : /*
8 : * Change history:
9 : *
10 : * 1.2.beta0 24 Nov 2002
11 : * - First version -- complete rewrite of inflate to simplify code, avoid
12 : * creation of window when not needed, minimize use of window when it is
13 : * needed, make inffast.c even faster, implement gzip decoding, and to
14 : * improve code readability and style over the previous zlib inflate code
15 : *
16 : * 1.2.beta1 25 Nov 2002
17 : * - Use pointers for available input and output checking in inffast.c
18 : * - Remove input and output counters in inffast.c
19 : * - Change inffast.c entry and loop from avail_in >= 7 to >= 6
20 : * - Remove unnecessary second byte pull from length extra in inffast.c
21 : * - Unroll direct copy to three copies per loop in inffast.c
22 : *
23 : * 1.2.beta2 4 Dec 2002
24 : * - Change external routine names to reduce potential conflicts
25 : * - Correct filename to inffixed.h for fixed tables in inflate.c
26 : * - Make hbuf[] unsigned char to match parameter type in inflate.c
27 : * - Change strm->next_out[-state->offset] to *(strm->next_out - state->offset)
28 : * to avoid negation problem on Alphas (64 bit) in inflate.c
29 : *
30 : * 1.2.beta3 22 Dec 2002
31 : * - Add comments on state->bits assertion in inffast.c
32 : * - Add comments on op field in inftrees.h
33 : * - Fix bug in reuse of allocated window after inflateReset()
34 : * - Remove bit fields--back to byte structure for speed
35 : * - Remove distance extra == 0 check in inflate_fast()--only helps for lengths
36 : * - Change post-increments to pre-increments in inflate_fast(), PPC biased?
37 : * - Add compile time option, POSTINC, to use post-increments instead (Intel?)
38 : * - Make MATCH copy in inflate() much faster for when inflate_fast() not used
39 : * - Use local copies of stream next and avail values, as well as local bit
40 : * buffer and bit count in inflate()--for speed when inflate_fast() not used
41 : *
42 : * 1.2.beta4 1 Jan 2003
43 : * - Split ptr - 257 statements in inflate_table() to avoid compiler warnings
44 : * - Move a comment on output buffer sizes from inffast.c to inflate.c
45 : * - Add comments in inffast.c to introduce the inflate_fast() routine
46 : * - Rearrange window copies in inflate_fast() for speed and simplification
47 : * - Unroll last copy for window match in inflate_fast()
48 : * - Use local copies of window variables in inflate_fast() for speed
49 : * - Pull out common write == 0 case for speed in inflate_fast()
50 : * - Make op and len in inflate_fast() unsigned for consistency
51 : * - Add FAR to lcode and dcode declarations in inflate_fast()
52 : * - Simplified bad distance check in inflate_fast()
53 : * - Added inflateBackInit(), inflateBack(), and inflateBackEnd() in new
54 : * source file infback.c to provide a call-back interface to inflate for
55 : * programs like gzip and unzip -- uses window as output buffer to avoid
56 : * window copying
57 : *
58 : * 1.2.beta5 1 Jan 2003
59 : * - Improved inflateBack() interface to allow the caller to provide initial
60 : * input in strm.
61 : * - Fixed stored blocks bug in inflateBack()
62 : *
63 : * 1.2.beta6 4 Jan 2003
64 : * - Added comments in inffast.c on effectiveness of POSTINC
65 : * - Typecasting all around to reduce compiler warnings
66 : * - Changed loops from while (1) or do {} while (1) to for (;;), again to
67 : * make compilers happy
68 : * - Changed type of window in inflateBackInit() to unsigned char *
69 : *
70 : * 1.2.beta7 27 Jan 2003
71 : * - Changed many types to unsigned or unsigned short to avoid warnings
72 : * - Added inflateCopy() function
73 : *
74 : * 1.2.0 9 Mar 2003
75 : * - Changed inflateBack() interface to provide separate opaque descriptors
76 : * for the in() and out() functions
77 : * - Changed inflateBack() argument and in_func typedef to swap the length
78 : * and buffer address return values for the input function
79 : * - Check next_in and next_out for Z_NULL on entry to inflate()
80 : *
81 : * The history for versions after 1.2.0 are in ChangeLog in zlib distribution.
82 : */
83 :
84 : #include "zutil.h"
85 : #include "inftrees.h"
86 : #include "inflate.h"
87 : #include "inffast.h"
88 :
89 : #ifdef MAKEFIXED
90 : # ifndef BUILDFIXED
91 : # define BUILDFIXED
92 : # endif
93 : #endif
94 :
95 : /* function prototypes */
96 : local void fixedtables OF((struct inflate_state FAR *state));
97 : local int updatewindow OF((z_streamp strm, unsigned out));
98 : #ifdef BUILDFIXED
99 : void makefixed OF((void));
100 : #endif
101 : local unsigned syncsearch OF((unsigned FAR *have, unsigned char FAR *buf,
102 : unsigned len));
103 :
104 0 : int ZEXPORT inflateReset(strm)
105 : z_streamp strm;
106 : {
107 : struct inflate_state FAR *state;
108 :
109 0 : if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
110 0 : state = (struct inflate_state FAR *)strm->state;
111 0 : strm->total_in = strm->total_out = state->total = 0;
112 0 : strm->msg = Z_NULL;
113 0 : strm->adler = 1; /* to support ill-conceived Java test suite */
114 0 : state->mode = HEAD;
115 0 : state->last = 0;
116 0 : state->havedict = 0;
117 0 : state->dmax = 32768U;
118 0 : state->head = Z_NULL;
119 0 : state->wsize = 0;
120 0 : state->whave = 0;
121 0 : state->write = 0;
122 0 : state->hold = 0;
123 0 : state->bits = 0;
124 0 : state->lencode = state->distcode = state->next = state->codes;
125 : Tracev((stderr, "inflate: reset\n"));
126 0 : return Z_OK;
127 0 : }
128 :
129 0 : int ZEXPORT inflatePrime(strm, bits, value)
130 : z_streamp strm;
131 : int bits;
132 : int value;
133 : {
134 : struct inflate_state FAR *state;
135 :
136 0 : if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
137 0 : state = (struct inflate_state FAR *)strm->state;
138 0 : if (bits > 16 || state->bits + bits > 32) return Z_STREAM_ERROR;
139 0 : value &= (1L << bits) - 1;
140 0 : state->hold += value << state->bits;
141 0 : state->bits += bits;
142 0 : return Z_OK;
143 0 : }
144 :
145 0 : int ZEXPORT inflateInit2_(strm, windowBits, version, stream_size)
146 : z_streamp strm;
147 : int windowBits;
148 : const char *version;
149 : int stream_size;
150 : {
151 : struct inflate_state FAR *state;
152 :
153 0 : if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
154 0 : stream_size != (int)(sizeof(z_stream)))
155 0 : return Z_VERSION_ERROR;
156 0 : if (strm == Z_NULL) return Z_STREAM_ERROR;
157 0 : strm->msg = Z_NULL; /* in case we return an error */
158 0 : if (strm->zalloc == (alloc_func)0) {
159 0 : strm->zalloc = zcalloc;
160 0 : strm->opaque = (voidpf)0;
161 0 : }
162 0 : if (strm->zfree == (free_func)0) strm->zfree = zcfree;
163 0 : state = (struct inflate_state FAR *)
164 0 : ZALLOC(strm, 1, sizeof(struct inflate_state));
165 0 : if (state == Z_NULL) return Z_MEM_ERROR;
166 : Tracev((stderr, "inflate: allocated\n"));
167 0 : strm->state = (struct internal_state FAR *)state;
168 0 : if (windowBits < 0) {
169 0 : state->wrap = 0;
170 0 : windowBits = -windowBits;
171 0 : }
172 : else {
173 0 : state->wrap = (windowBits >> 4) + 1;
174 : #ifdef GUNZIP
175 0 : if (windowBits < 48) windowBits &= 15;
176 : #endif
177 : }
178 0 : if (windowBits < 8 || windowBits > 15) {
179 0 : ZFREE(strm, state);
180 0 : strm->state = Z_NULL;
181 0 : return Z_STREAM_ERROR;
182 : }
183 0 : state->wbits = (unsigned)windowBits;
184 0 : state->window = Z_NULL;
185 0 : return inflateReset(strm);
186 0 : }
187 :
188 0 : int ZEXPORT inflateInit_(strm, version, stream_size)
189 : z_streamp strm;
190 : const char *version;
191 : int stream_size;
192 : {
193 0 : return inflateInit2_(strm, DEF_WBITS, version, stream_size);
194 : }
195 :
196 : /*
197 : Return state with length and distance decoding tables and index sizes set to
198 : fixed code decoding. Normally this returns fixed tables from inffixed.h.
199 : If BUILDFIXED is defined, then instead this routine builds the tables the
200 : first time it's called, and returns those tables the first time and
201 : thereafter. This reduces the size of the code by about 2K bytes, in
202 : exchange for a little execution time. However, BUILDFIXED should not be
203 : used for threaded applications, since the rewriting of the tables and virgin
204 : may not be thread-safe.
205 : */
206 0 : local void fixedtables(state)
207 : struct inflate_state FAR *state;
208 : {
209 : #ifdef BUILDFIXED
210 : static int virgin = 1;
211 : static code *lenfix, *distfix;
212 : static code fixed[544];
213 :
214 : /* build fixed huffman tables if first call (may not be thread safe) */
215 : if (virgin) {
216 : unsigned sym, bits;
217 : static code *next;
218 :
219 : /* literal/length table */
220 : sym = 0;
221 : while (sym < 144) state->lens[sym++] = 8;
222 : while (sym < 256) state->lens[sym++] = 9;
223 : while (sym < 280) state->lens[sym++] = 7;
224 : while (sym < 288) state->lens[sym++] = 8;
225 : next = fixed;
226 : lenfix = next;
227 : bits = 9;
228 : inflate_table(LENS, state->lens, 288, &(next), &(bits), state->work);
229 :
230 : /* distance table */
231 : sym = 0;
232 : while (sym < 32) state->lens[sym++] = 5;
233 : distfix = next;
234 : bits = 5;
235 : inflate_table(DISTS, state->lens, 32, &(next), &(bits), state->work);
236 :
237 : /* do this just once */
238 : virgin = 0;
239 : }
240 : #else /* !BUILDFIXED */
241 : # include "inffixed.h"
242 : #endif /* BUILDFIXED */
243 0 : state->lencode = lenfix;
244 0 : state->lenbits = 9;
245 0 : state->distcode = distfix;
246 0 : state->distbits = 5;
247 0 : }
248 :
249 : #ifdef MAKEFIXED
250 : #include <stdio.h>
251 :
252 : /*
253 : Write out the inffixed.h that is #include'd above. Defining MAKEFIXED also
254 : defines BUILDFIXED, so the tables are built on the fly. makefixed() writes
255 : those tables to stdout, which would be piped to inffixed.h. A small program
256 : can simply call makefixed to do this:
257 :
258 : void makefixed(void);
259 :
260 : int main(void)
261 : {
262 : makefixed();
263 : return 0;
264 : }
265 :
266 : Then that can be linked with zlib built with MAKEFIXED defined and run:
267 :
268 : a.out > inffixed.h
269 : */
270 : void makefixed()
271 : {
272 : unsigned low, size;
273 : struct inflate_state state;
274 :
275 : fixedtables(&state);
276 : puts(" /* inffixed.h -- table for decoding fixed codes");
277 : puts(" * Generated automatically by makefixed().");
278 : puts(" */");
279 : puts("");
280 : puts(" /* WARNING: this file should *not* be used by applications.");
281 : puts(" It is part of the implementation of this library and is");
282 : puts(" subject to change. Applications should only use zlib.h.");
283 : puts(" */");
284 : puts("");
285 : size = 1U << 9;
286 : printf(" static const code lenfix[%u] = {", size);
287 : low = 0;
288 : for (;;) {
289 : if ((low % 7) == 0) printf("\n ");
290 : printf("{%u,%u,%d}", state.lencode[low].op, state.lencode[low].bits,
291 : state.lencode[low].val);
292 : if (++low == size) break;
293 : putchar(',');
294 : }
295 : puts("\n };");
296 : size = 1U << 5;
297 : printf("\n static const code distfix[%u] = {", size);
298 : low = 0;
299 : for (;;) {
300 : if ((low % 6) == 0) printf("\n ");
301 : printf("{%u,%u,%d}", state.distcode[low].op, state.distcode[low].bits,
302 : state.distcode[low].val);
303 : if (++low == size) break;
304 : putchar(',');
305 : }
306 : puts("\n };");
307 : }
308 : #endif /* MAKEFIXED */
309 :
310 : /*
311 : Update the window with the last wsize (normally 32K) bytes written before
312 : returning. If window does not exist yet, create it. This is only called
313 : when a window is already in use, or when output has been written during this
314 : inflate call, but the end of the deflate stream has not been reached yet.
315 : It is also called to create a window for dictionary data when a dictionary
316 : is loaded.
317 :
318 : Providing output buffers larger than 32K to inflate() should provide a speed
319 : advantage, since only the last 32K of output is copied to the sliding window
320 : upon return from inflate(), and since all distances after the first 32K of
321 : output will fall in the output data, making match copies simpler and faster.
322 : The advantage may be dependent on the size of the processor's data caches.
323 : */
324 0 : local int updatewindow(strm, out)
325 : z_streamp strm;
326 : unsigned out;
327 : {
328 : struct inflate_state FAR *state;
329 : unsigned copy, dist;
330 :
331 0 : state = (struct inflate_state FAR *)strm->state;
332 :
333 : /* if it hasn't been done already, allocate space for the window */
334 0 : if (state->window == Z_NULL) {
335 0 : state->window = (unsigned char FAR *)
336 0 : ZALLOC(strm, 1U << state->wbits,
337 : sizeof(unsigned char));
338 0 : if (state->window == Z_NULL) return 1;
339 : }
340 :
341 : /* if window not in use yet, initialize */
342 0 : if (state->wsize == 0) {
343 0 : state->wsize = 1U << state->wbits;
344 0 : state->write = 0;
345 0 : state->whave = 0;
346 0 : }
347 :
348 : /* copy state->wsize or less output bytes into the circular window */
349 0 : copy = out - strm->avail_out;
350 0 : if (copy >= state->wsize) {
351 0 : zmemcpy(state->window, strm->next_out - state->wsize, state->wsize);
352 0 : state->write = 0;
353 0 : state->whave = state->wsize;
354 0 : }
355 : else {
356 0 : dist = state->wsize - state->write;
357 0 : if (dist > copy) dist = copy;
358 0 : zmemcpy(state->window + state->write, strm->next_out - copy, dist);
359 0 : copy -= dist;
360 0 : if (copy) {
361 0 : zmemcpy(state->window, strm->next_out - copy, copy);
362 0 : state->write = copy;
363 0 : state->whave = state->wsize;
364 0 : }
365 : else {
366 0 : state->write += dist;
367 0 : if (state->write == state->wsize) state->write = 0;
368 0 : if (state->whave < state->wsize) state->whave += dist;
369 : }
370 : }
371 0 : return 0;
372 0 : }
373 :
374 : /* Macros for inflate(): */
375 :
376 : /* check function to use adler32() for zlib or crc32() for gzip */
377 : #ifdef GUNZIP
378 : # define UPDATE(check, buf, len) \
379 : (state->flags ? crc32(check, buf, len) : adler32(check, buf, len))
380 : #else
381 : # define UPDATE(check, buf, len) adler32(check, buf, len)
382 : #endif
383 :
384 : /* check macros for header crc */
385 : #ifdef GUNZIP
386 : # define CRC2(check, word) \
387 : do { \
388 : hbuf[0] = (unsigned char)(word); \
389 : hbuf[1] = (unsigned char)((word) >> 8); \
390 : check = crc32(check, hbuf, 2); \
391 : } while (0)
392 :
393 : # define CRC4(check, word) \
394 : do { \
395 : hbuf[0] = (unsigned char)(word); \
396 : hbuf[1] = (unsigned char)((word) >> 8); \
397 : hbuf[2] = (unsigned char)((word) >> 16); \
398 : hbuf[3] = (unsigned char)((word) >> 24); \
399 : check = crc32(check, hbuf, 4); \
400 : } while (0)
401 : #endif
402 :
403 : /* Load registers with state in inflate() for speed */
404 : #define LOAD() \
405 : do { \
406 : put = strm->next_out; \
407 : left = strm->avail_out; \
408 : next = strm->next_in; \
409 : have = strm->avail_in; \
410 : hold = state->hold; \
411 : bits = state->bits; \
412 : } while (0)
413 :
414 : /* Restore state from registers in inflate() */
415 : #define RESTORE() \
416 : do { \
417 : strm->next_out = put; \
418 : strm->avail_out = left; \
419 : strm->next_in = next; \
420 : strm->avail_in = have; \
421 : state->hold = hold; \
422 : state->bits = bits; \
423 : } while (0)
424 :
425 : /* Clear the input bit accumulator */
426 : #define INITBITS() \
427 : do { \
428 : hold = 0; \
429 : bits = 0; \
430 : } while (0)
431 :
432 : /* Get a byte of input into the bit accumulator, or return from inflate()
433 : if there is no input available. */
434 : #define PULLBYTE() \
435 : do { \
436 : if (have == 0) goto inf_leave; \
437 : have--; \
438 : hold += (unsigned long)(*next++) << bits; \
439 : bits += 8; \
440 : } while (0)
441 :
442 : /* Assure that there are at least n bits in the bit accumulator. If there is
443 : not enough available input to do that, then return from inflate(). */
444 : #define NEEDBITS(n) \
445 : do { \
446 : while (bits < (unsigned)(n)) \
447 : PULLBYTE(); \
448 : } while (0)
449 :
450 : /* Return the low n bits of the bit accumulator (n < 16) */
451 : #define BITS(n) \
452 : ((unsigned)hold & ((1U << (n)) - 1))
453 :
454 : /* Remove n bits from the bit accumulator */
455 : #define DROPBITS(n) \
456 : do { \
457 : hold >>= (n); \
458 : bits -= (unsigned)(n); \
459 : } while (0)
460 :
461 : /* Remove zero to seven bits as needed to go to a byte boundary */
462 : #define BYTEBITS() \
463 : do { \
464 : hold >>= bits & 7; \
465 : bits -= bits & 7; \
466 : } while (0)
467 :
468 : /* Reverse the bytes in a 32-bit value */
469 : #define REVERSE(q) \
470 : ((((q) >> 24) & 0xff) + (((q) >> 8) & 0xff00) + \
471 : (((q) & 0xff00) << 8) + (((q) & 0xff) << 24))
472 :
473 : /*
474 : inflate() uses a state machine to process as much input data and generate as
475 : much output data as possible before returning. The state machine is
476 : structured roughly as follows:
477 :
478 : for (;;) switch (state) {
479 : ...
480 : case STATEn:
481 : if (not enough input data or output space to make progress)
482 : return;
483 : ... make progress ...
484 : state = STATEm;
485 : break;
486 : ...
487 : }
488 :
489 : so when inflate() is called again, the same case is attempted again, and
490 : if the appropriate resources are provided, the machine proceeds to the
491 : next state. The NEEDBITS() macro is usually the way the state evaluates
492 : whether it can proceed or should return. NEEDBITS() does the return if
493 : the requested bits are not available. The typical use of the BITS macros
494 : is:
495 :
496 : NEEDBITS(n);
497 : ... do something with BITS(n) ...
498 : DROPBITS(n);
499 :
500 : where NEEDBITS(n) either returns from inflate() if there isn't enough
501 : input left to load n bits into the accumulator, or it continues. BITS(n)
502 : gives the low n bits in the accumulator. When done, DROPBITS(n) drops
503 : the low n bits off the accumulator. INITBITS() clears the accumulator
504 : and sets the number of available bits to zero. BYTEBITS() discards just
505 : enough bits to put the accumulator on a byte boundary. After BYTEBITS()
506 : and a NEEDBITS(8), then BITS(8) would return the next byte in the stream.
507 :
508 : NEEDBITS(n) uses PULLBYTE() to get an available byte of input, or to return
509 : if there is no input available. The decoding of variable length codes uses
510 : PULLBYTE() directly in order to pull just enough bytes to decode the next
511 : code, and no more.
512 :
513 : Some states loop until they get enough input, making sure that enough
514 : state information is maintained to continue the loop where it left off
515 : if NEEDBITS() returns in the loop. For example, want, need, and keep
516 : would all have to actually be part of the saved state in case NEEDBITS()
517 : returns:
518 :
519 : case STATEw:
520 : while (want < need) {
521 : NEEDBITS(n);
522 : keep[want++] = BITS(n);
523 : DROPBITS(n);
524 : }
525 : state = STATEx;
526 : case STATEx:
527 :
528 : As shown above, if the next state is also the next case, then the break
529 : is omitted.
530 :
531 : A state may also return if there is not enough output space available to
532 : complete that state. Those states are copying stored data, writing a
533 : literal byte, and copying a matching string.
534 :
535 : When returning, a "goto inf_leave" is used to update the total counters,
536 : update the check value, and determine whether any progress has been made
537 : during that inflate() call in order to return the proper return code.
538 : Progress is defined as a change in either strm->avail_in or strm->avail_out.
539 : When there is a window, goto inf_leave will update the window with the last
540 : output written. If a goto inf_leave occurs in the middle of decompression
541 : and there is no window currently, goto inf_leave will create one and copy
542 : output to the window for the next call of inflate().
543 :
544 : In this implementation, the flush parameter of inflate() only affects the
545 : return code (per zlib.h). inflate() always writes as much as possible to
546 : strm->next_out, given the space available and the provided input--the effect
547 : documented in zlib.h of Z_SYNC_FLUSH. Furthermore, inflate() always defers
548 : the allocation of and copying into a sliding window until necessary, which
549 : provides the effect documented in zlib.h for Z_FINISH when the entire input
550 : stream available. So the only thing the flush parameter actually does is:
551 : when flush is set to Z_FINISH, inflate() cannot return Z_OK. Instead it
552 : will return Z_BUF_ERROR if it has not reached the end of the stream.
553 : */
554 :
555 0 : int ZEXPORT inflate(strm, flush)
556 : z_streamp strm;
557 : int flush;
558 : {
559 : struct inflate_state FAR *state;
560 : unsigned char FAR *next; /* next input */
561 : unsigned char FAR *put; /* next output */
562 : unsigned have, left; /* available input and output */
563 : unsigned long hold; /* bit buffer */
564 : unsigned bits; /* bits in bit buffer */
565 : unsigned in, out; /* save starting available input and output */
566 : unsigned copy; /* number of stored or match bytes to copy */
567 : unsigned char FAR *from; /* where to copy match bytes from */
568 : code this; /* current decoding table entry */
569 : code last; /* parent table entry */
570 : unsigned len; /* length to copy for repeats, bits to drop */
571 : int ret; /* return code */
572 : #ifdef GUNZIP
573 0 : unsigned char hbuf[4]; /* buffer for gzip header crc calculation */
574 : #endif
575 : static const unsigned short order[19] = /* permutation of code lengths */
576 : {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
577 :
578 0 : if (strm == Z_NULL || strm->state == Z_NULL || strm->next_out == Z_NULL ||
579 0 : (strm->next_in == Z_NULL && strm->avail_in != 0))
580 0 : return Z_STREAM_ERROR;
581 :
582 0 : state = (struct inflate_state FAR *)strm->state;
583 0 : if (state->mode == TYPE) state->mode = TYPEDO; /* skip check */
584 0 : LOAD();
585 : in = have;
586 : out = left;
587 : ret = Z_OK;
588 0 : for (;;)
589 0 : switch (state->mode) {
590 : case HEAD:
591 0 : if (state->wrap == 0) {
592 0 : state->mode = TYPEDO;
593 0 : break;
594 : }
595 0 : NEEDBITS(16);
596 : #ifdef GUNZIP
597 0 : if ((state->wrap & 2) && hold == 0x8b1f) { /* gzip header */
598 0 : state->check = crc32(0L, Z_NULL, 0);
599 0 : CRC2(state->check, hold);
600 : INITBITS();
601 0 : state->mode = FLAGS;
602 0 : break;
603 : }
604 0 : state->flags = 0; /* expect zlib header */
605 0 : if (state->head != Z_NULL)
606 0 : state->head->done = -1;
607 0 : if (!(state->wrap & 1) || /* check if zlib header allowed */
608 : #else
609 : if (
610 : #endif
611 0 : ((BITS(8) << 8) + (hold >> 8)) % 31) {
612 : #ifdef SMALL
613 : strm->msg = "error";
614 : #else
615 0 : strm->msg = (char *)"incorrect header check";
616 : #endif
617 0 : state->mode = BAD;
618 0 : break;
619 : }
620 0 : if (BITS(4) != Z_DEFLATED) {
621 : #ifdef SMALL
622 : strm->msg = "error";
623 : #else
624 0 : strm->msg = (char *)"unknown compression method";
625 : #endif
626 0 : state->mode = BAD;
627 0 : break;
628 : }
629 0 : DROPBITS(4);
630 0 : len = BITS(4) + 8;
631 0 : if (len > state->wbits) {
632 : #ifdef SMALL
633 : strm->msg = "error";
634 : #else
635 0 : strm->msg = (char *)"invalid window size";
636 : #endif
637 0 : state->mode = BAD;
638 0 : break;
639 : }
640 0 : state->dmax = 1U << len;
641 : Tracev((stderr, "inflate: zlib header ok\n"));
642 0 : strm->adler = state->check = adler32(0L, Z_NULL, 0);
643 0 : state->mode = hold & 0x200 ? DICTID : TYPE;
644 : INITBITS();
645 0 : break;
646 : #ifdef GUNZIP
647 : case FLAGS:
648 0 : NEEDBITS(16);
649 0 : state->flags = (int)(hold);
650 0 : if ((state->flags & 0xff) != Z_DEFLATED) {
651 : #ifdef SMALL
652 : strm->msg = "error";
653 : #else
654 0 : strm->msg = (char *)"unknown compression method";
655 : #endif
656 0 : state->mode = BAD;
657 0 : break;
658 : }
659 0 : if (state->flags & 0xe000) {
660 : #ifdef SMALL
661 : strm->msg = "error";
662 : #else
663 0 : strm->msg = (char *)"unknown header flags set";
664 : #endif
665 0 : state->mode = BAD;
666 0 : break;
667 : }
668 0 : if (state->head != Z_NULL)
669 0 : state->head->text = (int)((hold >> 8) & 1);
670 0 : if (state->flags & 0x0200) CRC2(state->check, hold);
671 : INITBITS();
672 0 : state->mode = TIME;
673 : case TIME:
674 0 : NEEDBITS(32);
675 0 : if (state->head != Z_NULL)
676 0 : state->head->time = hold;
677 0 : if (state->flags & 0x0200) CRC4(state->check, hold);
678 : INITBITS();
679 0 : state->mode = OS;
680 : case OS:
681 0 : NEEDBITS(16);
682 0 : if (state->head != Z_NULL) {
683 0 : state->head->xflags = (int)(hold & 0xff);
684 0 : state->head->os = (int)(hold >> 8);
685 0 : }
686 0 : if (state->flags & 0x0200) CRC2(state->check, hold);
687 : INITBITS();
688 0 : state->mode = EXLEN;
689 : case EXLEN:
690 0 : if (state->flags & 0x0400) {
691 0 : NEEDBITS(16);
692 0 : state->length = (unsigned)(hold);
693 0 : if (state->head != Z_NULL)
694 0 : state->head->extra_len = (unsigned)hold;
695 0 : if (state->flags & 0x0200) CRC2(state->check, hold);
696 : INITBITS();
697 0 : }
698 0 : else if (state->head != Z_NULL)
699 0 : state->head->extra = Z_NULL;
700 0 : state->mode = EXTRA;
701 : case EXTRA:
702 0 : if (state->flags & 0x0400) {
703 0 : copy = state->length;
704 0 : if (copy > have) copy = have;
705 0 : if (copy) {
706 0 : if (state->head != Z_NULL &&
707 0 : state->head->extra != Z_NULL) {
708 0 : len = state->head->extra_len - state->length;
709 0 : zmemcpy(state->head->extra + len, next,
710 : len + copy > state->head->extra_max ?
711 : state->head->extra_max - len : copy);
712 0 : }
713 0 : if (state->flags & 0x0200)
714 0 : state->check = crc32(state->check, next, copy);
715 0 : have -= copy;
716 0 : next += copy;
717 0 : state->length -= copy;
718 0 : }
719 0 : if (state->length) goto inf_leave;
720 : }
721 0 : state->length = 0;
722 0 : state->mode = NAME;
723 : case NAME:
724 0 : if (state->flags & 0x0800) {
725 0 : if (have == 0) goto inf_leave;
726 : copy = 0;
727 0 : do {
728 0 : len = (unsigned)(next[copy++]);
729 0 : if (state->head != Z_NULL &&
730 0 : state->head->name != Z_NULL &&
731 0 : state->length < state->head->name_max)
732 0 : state->head->name[state->length++] = len;
733 0 : } while (len && copy < have);
734 0 : if (state->flags & 0x0200)
735 0 : state->check = crc32(state->check, next, copy);
736 0 : have -= copy;
737 0 : next += copy;
738 0 : if (len) goto inf_leave;
739 : }
740 0 : else if (state->head != Z_NULL)
741 0 : state->head->name = Z_NULL;
742 0 : state->length = 0;
743 0 : state->mode = COMMENT;
744 : case COMMENT:
745 0 : if (state->flags & 0x1000) {
746 0 : if (have == 0) goto inf_leave;
747 : copy = 0;
748 0 : do {
749 0 : len = (unsigned)(next[copy++]);
750 0 : if (state->head != Z_NULL &&
751 0 : state->head->comment != Z_NULL &&
752 0 : state->length < state->head->comm_max)
753 0 : state->head->comment[state->length++] = len;
754 0 : } while (len && copy < have);
755 0 : if (state->flags & 0x0200)
756 0 : state->check = crc32(state->check, next, copy);
757 0 : have -= copy;
758 0 : next += copy;
759 0 : if (len) goto inf_leave;
760 : }
761 0 : else if (state->head != Z_NULL)
762 0 : state->head->comment = Z_NULL;
763 0 : state->mode = HCRC;
764 : case HCRC:
765 0 : if (state->flags & 0x0200) {
766 0 : NEEDBITS(16);
767 0 : if (hold != (state->check & 0xffff)) {
768 : #ifdef SMALL
769 : strm->msg = "error";
770 : #else
771 0 : strm->msg = (char *)"header crc mismatch";
772 : #endif
773 0 : state->mode = BAD;
774 0 : break;
775 : }
776 : INITBITS();
777 0 : }
778 0 : if (state->head != Z_NULL) {
779 0 : state->head->hcrc = (int)((state->flags >> 9) & 1);
780 0 : state->head->done = 1;
781 0 : }
782 0 : strm->adler = state->check = crc32(0L, Z_NULL, 0);
783 0 : state->mode = TYPE;
784 0 : break;
785 : #endif
786 : case DICTID:
787 0 : NEEDBITS(32);
788 0 : strm->adler = state->check = REVERSE(hold);
789 : INITBITS();
790 0 : state->mode = DICT;
791 : case DICT:
792 0 : if (state->havedict == 0) {
793 0 : RESTORE();
794 0 : return Z_NEED_DICT;
795 : }
796 0 : strm->adler = state->check = adler32(0L, Z_NULL, 0);
797 0 : state->mode = TYPE;
798 : case TYPE:
799 0 : if (flush == Z_BLOCK) goto inf_leave;
800 : case TYPEDO:
801 0 : if (state->last) {
802 0 : BYTEBITS();
803 0 : state->mode = CHECK;
804 0 : break;
805 : }
806 0 : NEEDBITS(3);
807 0 : state->last = BITS(1);
808 0 : DROPBITS(1);
809 0 : switch (BITS(2)) {
810 : case 0: /* stored block */
811 : Tracev((stderr, "inflate: stored block%s\n",
812 : state->last ? " (last)" : ""));
813 0 : state->mode = STORED;
814 0 : break;
815 : case 1: /* fixed block */
816 0 : fixedtables(state);
817 : Tracev((stderr, "inflate: fixed codes block%s\n",
818 : state->last ? " (last)" : ""));
819 0 : state->mode = LEN; /* decode codes */
820 0 : break;
821 : case 2: /* dynamic block */
822 : Tracev((stderr, "inflate: dynamic codes block%s\n",
823 : state->last ? " (last)" : ""));
824 0 : state->mode = TABLE;
825 0 : break;
826 : case 3:
827 : #ifdef SMALL
828 : strm->msg = "error";
829 : #else
830 0 : strm->msg = (char *)"invalid block type";
831 : #endif
832 0 : state->mode = BAD;
833 0 : }
834 0 : DROPBITS(2);
835 0 : break;
836 : case STORED:
837 0 : BYTEBITS(); /* go to byte boundary */
838 0 : NEEDBITS(32);
839 0 : if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) {
840 : #ifdef SMALL
841 : strm->msg = "error";
842 : #else
843 0 : strm->msg = (char *)"invalid stored block lengths";
844 : #endif
845 0 : state->mode = BAD;
846 0 : break;
847 : }
848 0 : state->length = (unsigned)hold & 0xffff;
849 : Tracev((stderr, "inflate: stored length %u\n",
850 : state->length));
851 : INITBITS();
852 0 : state->mode = COPY;
853 : case COPY:
854 0 : copy = state->length;
855 0 : if (copy) {
856 0 : if (copy > have) copy = have;
857 0 : if (copy > left) copy = left;
858 0 : if (copy == 0) goto inf_leave;
859 0 : zmemcpy(put, next, copy);
860 0 : have -= copy;
861 0 : next += copy;
862 0 : left -= copy;
863 0 : put += copy;
864 0 : state->length -= copy;
865 0 : break;
866 : }
867 : Tracev((stderr, "inflate: stored end\n"));
868 0 : state->mode = TYPE;
869 0 : break;
870 : case TABLE:
871 0 : NEEDBITS(14);
872 0 : state->nlen = BITS(5) + 257;
873 0 : DROPBITS(5);
874 0 : state->ndist = BITS(5) + 1;
875 0 : DROPBITS(5);
876 0 : state->ncode = BITS(4) + 4;
877 0 : DROPBITS(4);
878 : #ifndef PKZIP_BUG_WORKAROUND
879 0 : if (state->nlen > 286 || state->ndist > 30) {
880 : #ifdef SMALL
881 : strm->msg = "error";
882 : #else
883 0 : strm->msg = (char *)"too many length or distance symbols";
884 : #endif
885 0 : state->mode = BAD;
886 0 : break;
887 : }
888 : #endif
889 : Tracev((stderr, "inflate: table sizes ok\n"));
890 0 : state->have = 0;
891 0 : state->mode = LENLENS;
892 : case LENLENS:
893 0 : while (state->have < state->ncode) {
894 0 : NEEDBITS(3);
895 0 : state->lens[order[state->have++]] = (unsigned short)BITS(3);
896 0 : DROPBITS(3);
897 : }
898 0 : while (state->have < 19)
899 0 : state->lens[order[state->have++]] = 0;
900 0 : state->next = state->codes;
901 0 : state->lencode = (code const FAR *)(state->next);
902 0 : state->lenbits = 7;
903 0 : ret = inflate_table(CODES, state->lens, 19, &(state->next),
904 0 : &(state->lenbits), state->work);
905 0 : if (ret) {
906 : #ifdef SMALL
907 : strm->msg = "error";
908 : #else
909 0 : strm->msg = (char *)"invalid code lengths set";
910 : #endif
911 0 : state->mode = BAD;
912 0 : break;
913 : }
914 : Tracev((stderr, "inflate: code lengths ok\n"));
915 0 : state->have = 0;
916 0 : state->mode = CODELENS;
917 : case CODELENS:
918 0 : while (state->have < state->nlen + state->ndist) {
919 0 : for (;;) {
920 0 : this = state->lencode[BITS(state->lenbits)];
921 0 : if ((unsigned)(this.bits) <= bits) break;
922 0 : PULLBYTE();
923 : }
924 0 : if (this.val < 16) {
925 0 : NEEDBITS(this.bits);
926 0 : DROPBITS(this.bits);
927 0 : state->lens[state->have++] = this.val;
928 0 : }
929 : else {
930 0 : if (this.val == 16) {
931 0 : NEEDBITS(this.bits + 2);
932 0 : DROPBITS(this.bits);
933 0 : if (state->have == 0) {
934 : #ifdef SMALL
935 : strm->msg = "error";
936 : #else
937 0 : strm->msg = (char *)"invalid bit length repeat";
938 : #endif
939 0 : state->mode = BAD;
940 0 : break;
941 : }
942 0 : len = state->lens[state->have - 1];
943 0 : copy = 3 + BITS(2);
944 0 : DROPBITS(2);
945 0 : }
946 0 : else if (this.val == 17) {
947 0 : NEEDBITS(this.bits + 3);
948 0 : DROPBITS(this.bits);
949 : len = 0;
950 0 : copy = 3 + BITS(3);
951 0 : DROPBITS(3);
952 0 : }
953 : else {
954 0 : NEEDBITS(this.bits + 7);
955 0 : DROPBITS(this.bits);
956 : len = 0;
957 0 : copy = 11 + BITS(7);
958 0 : DROPBITS(7);
959 : }
960 0 : if (state->have + copy > state->nlen + state->ndist) {
961 : #ifdef SMALL
962 : strm->msg = "error";
963 : #else
964 0 : strm->msg = (char *)"invalid bit length repeat";
965 : #endif
966 0 : state->mode = BAD;
967 0 : break;
968 : }
969 0 : while (copy--)
970 0 : state->lens[state->have++] = (unsigned short)len;
971 : }
972 : }
973 :
974 : /* handle error breaks in while */
975 0 : if (state->mode == BAD) break;
976 :
977 : /* build code tables */
978 0 : state->next = state->codes;
979 0 : state->lencode = (code const FAR *)(state->next);
980 0 : state->lenbits = 9;
981 0 : ret = inflate_table(LENS, state->lens, state->nlen, &(state->next),
982 0 : &(state->lenbits), state->work);
983 0 : if (ret) {
984 : #ifdef SMALL
985 : strm->msg = "error";
986 : #else
987 0 : strm->msg = (char *)"invalid literal/lengths set";
988 : #endif
989 0 : state->mode = BAD;
990 0 : break;
991 : }
992 0 : state->distcode = (code const FAR *)(state->next);
993 0 : state->distbits = 6;
994 0 : ret = inflate_table(DISTS, state->lens + state->nlen, state->ndist,
995 : &(state->next), &(state->distbits), state->work);
996 0 : if (ret) {
997 : #ifdef SMALL
998 : strm->msg = "error";
999 : #else
1000 0 : strm->msg = (char *)"invalid distances set";
1001 : #endif
1002 0 : state->mode = BAD;
1003 0 : break;
1004 : }
1005 : Tracev((stderr, "inflate: codes ok\n"));
1006 0 : state->mode = LEN;
1007 : case LEN:
1008 : #ifndef SLOW
1009 0 : if (have >= 6 && left >= 258) {
1010 0 : RESTORE();
1011 0 : inflate_fast(strm, out);
1012 0 : LOAD();
1013 0 : break;
1014 : }
1015 : #endif
1016 0 : for (;;) {
1017 0 : this = state->lencode[BITS(state->lenbits)];
1018 0 : if ((unsigned)(this.bits) <= bits) break;
1019 0 : PULLBYTE();
1020 : }
1021 0 : if (this.op && (this.op & 0xf0) == 0) {
1022 : last = this;
1023 0 : for (;;) {
1024 0 : this = state->lencode[last.val +
1025 0 : (BITS(last.bits + last.op) >> last.bits)];
1026 0 : if ((unsigned)(last.bits + this.bits) <= bits) break;
1027 0 : PULLBYTE();
1028 : }
1029 0 : DROPBITS(last.bits);
1030 0 : }
1031 0 : DROPBITS(this.bits);
1032 0 : state->length = (unsigned)this.val;
1033 0 : if ((int)(this.op) == 0) {
1034 : Tracevv((stderr, this.val >= 0x20 && this.val < 0x7f ?
1035 : "inflate: literal '%c'\n" :
1036 : "inflate: literal 0x%02x\n", this.val));
1037 0 : state->mode = LIT;
1038 0 : break;
1039 : }
1040 0 : if (this.op & 32) {
1041 : Tracevv((stderr, "inflate: end of block\n"));
1042 0 : state->mode = TYPE;
1043 0 : break;
1044 : }
1045 0 : if (this.op & 64) {
1046 : #ifdef SMALL
1047 : strm->msg = "error";
1048 : #else
1049 0 : strm->msg = (char *)"invalid literal/length code";
1050 : #endif
1051 0 : state->mode = BAD;
1052 0 : break;
1053 : }
1054 0 : state->extra = (unsigned)(this.op) & 15;
1055 0 : state->mode = LENEXT;
1056 : case LENEXT:
1057 0 : if (state->extra) {
1058 0 : NEEDBITS(state->extra);
1059 0 : state->length += BITS(state->extra);
1060 0 : DROPBITS(state->extra);
1061 0 : }
1062 : Tracevv((stderr, "inflate: length %u\n", state->length));
1063 0 : state->mode = DIST;
1064 : case DIST:
1065 0 : for (;;) {
1066 0 : this = state->distcode[BITS(state->distbits)];
1067 0 : if ((unsigned)(this.bits) <= bits) break;
1068 0 : PULLBYTE();
1069 : }
1070 0 : if ((this.op & 0xf0) == 0) {
1071 : last = this;
1072 0 : for (;;) {
1073 0 : this = state->distcode[last.val +
1074 0 : (BITS(last.bits + last.op) >> last.bits)];
1075 0 : if ((unsigned)(last.bits + this.bits) <= bits) break;
1076 0 : PULLBYTE();
1077 : }
1078 0 : DROPBITS(last.bits);
1079 0 : }
1080 0 : DROPBITS(this.bits);
1081 0 : if (this.op & 64) {
1082 : #ifdef SMALL
1083 : strm->msg = "error";
1084 : #else
1085 0 : strm->msg = (char *)"invalid distance code";
1086 : #endif
1087 0 : state->mode = BAD;
1088 0 : break;
1089 : }
1090 0 : state->offset = (unsigned)this.val;
1091 0 : state->extra = (unsigned)(this.op) & 15;
1092 0 : state->mode = DISTEXT;
1093 : case DISTEXT:
1094 0 : if (state->extra) {
1095 0 : NEEDBITS(state->extra);
1096 0 : state->offset += BITS(state->extra);
1097 0 : DROPBITS(state->extra);
1098 0 : }
1099 : #ifdef INFLATE_STRICT
1100 : if (state->offset > state->dmax) {
1101 : strm->msg = (char *)"invalid distance too far back";
1102 : state->mode = BAD;
1103 : break;
1104 : }
1105 : #endif
1106 0 : if (state->offset > state->whave + out - left) {
1107 : #ifdef SMALL
1108 : strm->msg = "error";
1109 : #else
1110 0 : strm->msg = (char *)"invalid distance too far back";
1111 : #endif
1112 0 : state->mode = BAD;
1113 0 : break;
1114 : }
1115 : Tracevv((stderr, "inflate: distance %u\n", state->offset));
1116 0 : state->mode = MATCH;
1117 : case MATCH:
1118 0 : if (left == 0) goto inf_leave;
1119 0 : copy = out - left;
1120 0 : if (state->offset > copy) { /* copy from window */
1121 0 : copy = state->offset - copy;
1122 0 : if (copy > state->write) {
1123 0 : copy -= state->write;
1124 0 : from = state->window + (state->wsize - copy);
1125 0 : }
1126 : else
1127 0 : from = state->window + (state->write - copy);
1128 0 : if (copy > state->length) copy = state->length;
1129 : }
1130 : else { /* copy from output */
1131 0 : from = put - state->offset;
1132 0 : copy = state->length;
1133 : }
1134 0 : if (copy > left) copy = left;
1135 0 : left -= copy;
1136 0 : state->length -= copy;
1137 0 : do {
1138 0 : *put++ = *from++;
1139 0 : } while (--copy);
1140 0 : if (state->length == 0) state->mode = LEN;
1141 : break;
1142 : case LIT:
1143 0 : if (left == 0) goto inf_leave;
1144 0 : *put++ = (unsigned char)(state->length);
1145 0 : left--;
1146 0 : state->mode = LEN;
1147 0 : break;
1148 : case CHECK:
1149 0 : if (state->wrap) {
1150 0 : NEEDBITS(32);
1151 0 : out -= left;
1152 0 : strm->total_out += out;
1153 0 : state->total += out;
1154 0 : if (out)
1155 0 : strm->adler = state->check =
1156 0 : UPDATE(state->check, put - out, out);
1157 : out = left;
1158 0 : if ((
1159 : #ifdef GUNZIP
1160 0 : state->flags ? hold :
1161 : #endif
1162 0 : REVERSE(hold)) != state->check) {
1163 : #ifdef SMALL
1164 : strm->msg = "error";
1165 : #else
1166 0 : strm->msg = (char *)"incorrect data check";
1167 : #endif
1168 0 : state->mode = BAD;
1169 0 : break;
1170 : }
1171 : INITBITS();
1172 : Tracev((stderr, "inflate: check matches trailer\n"));
1173 0 : }
1174 : #ifdef GUNZIP
1175 0 : state->mode = LENGTH;
1176 : case LENGTH:
1177 0 : if (state->wrap && state->flags) {
1178 0 : NEEDBITS(32);
1179 0 : if (hold != (state->total & 0xffffffffUL)) {
1180 : #ifdef SMALL
1181 : strm->msg = "error";
1182 : #else
1183 0 : strm->msg = (char *)"incorrect length check";
1184 : #endif
1185 0 : state->mode = BAD;
1186 0 : break;
1187 : }
1188 : INITBITS();
1189 : Tracev((stderr, "inflate: length matches trailer\n"));
1190 0 : }
1191 : #endif
1192 0 : state->mode = DONE;
1193 : case DONE:
1194 : ret = Z_STREAM_END;
1195 0 : goto inf_leave;
1196 : case BAD:
1197 : ret = Z_DATA_ERROR;
1198 0 : goto inf_leave;
1199 : case MEM:
1200 0 : return Z_MEM_ERROR;
1201 : case SYNC:
1202 : default:
1203 0 : return Z_STREAM_ERROR;
1204 : }
1205 :
1206 : /*
1207 : Return from inflate(), updating the total counts and the check value.
1208 : If there was no progress during the inflate() call, return a buffer
1209 : error. Call updatewindow() to create and/or update the window state.
1210 : Note: a memory error from inflate() is non-recoverable.
1211 : */
1212 : inf_leave:
1213 0 : RESTORE();
1214 0 : if (state->wsize || (state->mode < CHECK && out != strm->avail_out))
1215 0 : if (updatewindow(strm, out)) {
1216 0 : state->mode = MEM;
1217 0 : return Z_MEM_ERROR;
1218 : }
1219 0 : in -= strm->avail_in;
1220 0 : out -= strm->avail_out;
1221 0 : strm->total_in += in;
1222 0 : strm->total_out += out;
1223 0 : state->total += out;
1224 0 : if (state->wrap && out)
1225 0 : strm->adler = state->check =
1226 0 : UPDATE(state->check, strm->next_out - out, out);
1227 0 : strm->data_type = state->bits + (state->last ? 64 : 0) +
1228 0 : (state->mode == TYPE ? 128 : 0);
1229 0 : if (((in == 0 && out == 0) || flush == Z_FINISH) && ret == Z_OK)
1230 0 : ret = Z_BUF_ERROR;
1231 0 : return ret;
1232 0 : }
1233 :
1234 0 : int ZEXPORT inflateEnd(strm)
1235 : z_streamp strm;
1236 : {
1237 : struct inflate_state FAR *state;
1238 0 : if (strm == Z_NULL || strm->state == Z_NULL || strm->zfree == (free_func)0)
1239 0 : return Z_STREAM_ERROR;
1240 0 : state = (struct inflate_state FAR *)strm->state;
1241 0 : if (state->window != Z_NULL) ZFREE(strm, state->window);
1242 0 : ZFREE(strm, strm->state);
1243 0 : strm->state = Z_NULL;
1244 : Tracev((stderr, "inflate: end\n"));
1245 0 : return Z_OK;
1246 0 : }
1247 :
1248 0 : int ZEXPORT inflateSetDictionary(strm, dictionary, dictLength)
1249 : z_streamp strm;
1250 : const Bytef *dictionary;
1251 : uInt dictLength;
1252 : {
1253 : struct inflate_state FAR *state;
1254 : unsigned long id;
1255 :
1256 : /* check state */
1257 0 : if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
1258 0 : state = (struct inflate_state FAR *)strm->state;
1259 0 : if (state->wrap != 0 && state->mode != DICT)
1260 0 : return Z_STREAM_ERROR;
1261 :
1262 : /* check for correct dictionary id */
1263 0 : if (state->mode == DICT) {
1264 0 : id = adler32(0L, Z_NULL, 0);
1265 0 : id = adler32(id, dictionary, dictLength);
1266 0 : if (id != state->check)
1267 0 : return Z_DATA_ERROR;
1268 : }
1269 :
1270 : /* copy dictionary to window */
1271 0 : if (updatewindow(strm, strm->avail_out)) {
1272 0 : state->mode = MEM;
1273 0 : return Z_MEM_ERROR;
1274 : }
1275 0 : if (dictLength > state->wsize) {
1276 0 : zmemcpy(state->window, dictionary + dictLength - state->wsize,
1277 : state->wsize);
1278 0 : state->whave = state->wsize;
1279 0 : }
1280 : else {
1281 0 : zmemcpy(state->window + state->wsize - dictLength, dictionary,
1282 : dictLength);
1283 0 : state->whave = dictLength;
1284 : }
1285 0 : state->havedict = 1;
1286 : Tracev((stderr, "inflate: dictionary set\n"));
1287 0 : return Z_OK;
1288 0 : }
1289 :
1290 0 : int ZEXPORT inflateGetHeader(strm, head)
1291 : z_streamp strm;
1292 : gz_headerp head;
1293 : {
1294 : struct inflate_state FAR *state;
1295 :
1296 : /* check state */
1297 0 : if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
1298 0 : state = (struct inflate_state FAR *)strm->state;
1299 0 : if ((state->wrap & 2) == 0) return Z_STREAM_ERROR;
1300 :
1301 : /* save header structure */
1302 0 : state->head = head;
1303 0 : head->done = 0;
1304 0 : return Z_OK;
1305 0 : }
1306 :
1307 : /*
1308 : Search buf[0..len-1] for the pattern: 0, 0, 0xff, 0xff. Return when found
1309 : or when out of input. When called, *have is the number of pattern bytes
1310 : found in order so far, in 0..3. On return *have is updated to the new
1311 : state. If on return *have equals four, then the pattern was found and the
1312 : return value is how many bytes were read including the last byte of the
1313 : pattern. If *have is less than four, then the pattern has not been found
1314 : yet and the return value is len. In the latter case, syncsearch() can be
1315 : called again with more data and the *have state. *have is initialized to
1316 : zero for the first call.
1317 : */
1318 0 : local unsigned syncsearch(have, buf, len)
1319 : unsigned FAR *have;
1320 : unsigned char FAR *buf;
1321 : unsigned len;
1322 : {
1323 : unsigned got;
1324 : unsigned next;
1325 :
1326 0 : got = *have;
1327 : next = 0;
1328 0 : while (next < len && got < 4) {
1329 0 : if ((int)(buf[next]) == (got < 2 ? 0 : 0xff))
1330 0 : got++;
1331 0 : else if (buf[next])
1332 0 : got = 0;
1333 : else
1334 0 : got = 4 - got;
1335 0 : next++;
1336 : }
1337 0 : *have = got;
1338 0 : return next;
1339 : }
1340 :
1341 0 : int ZEXPORT inflateSync(strm)
1342 : z_streamp strm;
1343 : {
1344 : unsigned len; /* number of bytes to look at or looked at */
1345 : unsigned long in, out; /* temporary to save total_in and total_out */
1346 0 : unsigned char buf[4]; /* to restore bit buffer to byte string */
1347 : struct inflate_state FAR *state;
1348 :
1349 : /* check parameters */
1350 0 : if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
1351 0 : state = (struct inflate_state FAR *)strm->state;
1352 0 : if (strm->avail_in == 0 && state->bits < 8) return Z_BUF_ERROR;
1353 :
1354 : /* if first time, start search in bit buffer */
1355 0 : if (state->mode != SYNC) {
1356 0 : state->mode = SYNC;
1357 0 : state->hold <<= state->bits & 7;
1358 0 : state->bits -= state->bits & 7;
1359 : len = 0;
1360 0 : while (state->bits >= 8) {
1361 0 : buf[len++] = (unsigned char)(state->hold);
1362 0 : state->hold >>= 8;
1363 0 : state->bits -= 8;
1364 : }
1365 0 : state->have = 0;
1366 0 : syncsearch(&(state->have), buf, len);
1367 0 : }
1368 :
1369 : /* search available input */
1370 0 : len = syncsearch(&(state->have), strm->next_in, strm->avail_in);
1371 0 : strm->avail_in -= len;
1372 0 : strm->next_in += len;
1373 0 : strm->total_in += len;
1374 :
1375 : /* return no joy or set up to restart inflate() on a new block */
1376 0 : if (state->have != 4) return Z_DATA_ERROR;
1377 0 : in = strm->total_in; out = strm->total_out;
1378 0 : inflateReset(strm);
1379 0 : strm->total_in = in; strm->total_out = out;
1380 0 : state->mode = TYPE;
1381 0 : return Z_OK;
1382 0 : }
1383 :
1384 : /*
1385 : Returns true if inflate is currently at the end of a block generated by
1386 : Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
1387 : implementation to provide an additional safety check. PPP uses
1388 : Z_SYNC_FLUSH but removes the length bytes of the resulting empty stored
1389 : block. When decompressing, PPP checks that at the end of input packet,
1390 : inflate is waiting for these length bytes.
1391 : */
1392 0 : int ZEXPORT inflateSyncPoint(strm)
1393 : z_streamp strm;
1394 : {
1395 : struct inflate_state FAR *state;
1396 :
1397 0 : if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
1398 0 : state = (struct inflate_state FAR *)strm->state;
1399 0 : return state->mode == STORED && state->bits == 0;
1400 0 : }
1401 :
1402 0 : int ZEXPORT inflateCopy(dest, source)
1403 : z_streamp dest;
1404 : z_streamp source;
1405 : {
1406 : struct inflate_state FAR *state;
1407 : struct inflate_state FAR *copy;
1408 : unsigned char FAR *window;
1409 : unsigned wsize;
1410 :
1411 : /* check input */
1412 0 : if (dest == Z_NULL || source == Z_NULL || source->state == Z_NULL ||
1413 0 : source->zalloc == (alloc_func)0 || source->zfree == (free_func)0)
1414 0 : return Z_STREAM_ERROR;
1415 0 : state = (struct inflate_state FAR *)source->state;
1416 :
1417 : /* allocate space */
1418 0 : copy = (struct inflate_state FAR *)
1419 0 : ZALLOC(source, 1, sizeof(struct inflate_state));
1420 0 : if (copy == Z_NULL) return Z_MEM_ERROR;
1421 : window = Z_NULL;
1422 0 : if (state->window != Z_NULL) {
1423 : window = (unsigned char FAR *)
1424 0 : ZALLOC(source, 1U << state->wbits, sizeof(unsigned char));
1425 0 : if (window == Z_NULL) {
1426 0 : ZFREE(source, copy);
1427 0 : return Z_MEM_ERROR;
1428 : }
1429 : }
1430 :
1431 : /* copy state */
1432 0 : zmemcpy(dest, source, sizeof(z_stream));
1433 0 : zmemcpy(copy, state, sizeof(struct inflate_state));
1434 0 : if (state->lencode >= state->codes &&
1435 0 : state->lencode <= state->codes + ENOUGH - 1) {
1436 0 : copy->lencode = copy->codes + (state->lencode - state->codes);
1437 0 : copy->distcode = copy->codes + (state->distcode - state->codes);
1438 0 : }
1439 0 : copy->next = copy->codes + (state->next - state->codes);
1440 0 : if (window != Z_NULL) {
1441 0 : wsize = 1U << state->wbits;
1442 0 : zmemcpy(window, state->window, wsize);
1443 0 : }
1444 0 : copy->window = window;
1445 0 : dest->state = (struct internal_state FAR *)copy;
1446 0 : return Z_OK;
1447 0 : }
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