Line data Source code
1 : /* inflate.c -- zlib decompression
2 : * Copyright (C) 1995-2016 Mark Adler
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
48 : * - Pull out common wnext == 0 case for speed in inflate_fast()
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 */
95 : local int inflateStateCheck OF((z_streamp strm));
96 : local void fixedtables OF((struct inflate_state FAR *state));
97 : local int updatewindow OF((z_streamp strm, const unsigned char FAR *end,
98 : unsigned copy));
99 : #ifdef BUILDFIXED
100 : void makefixed OF((void));
101 : #endif
102 : local unsigned syncsearch OF((unsigned FAR *have, const unsigned char FAR *buf,
103 : unsigned len));
104 :
105 2606 : local int inflateStateCheck(strm)
106 : z_streamp strm;
107 : {
108 : struct inflate_state FAR *state;
109 5212 : if (strm == Z_NULL ||
110 5212 : strm->zalloc == (alloc_func)0 || strm->zfree == (free_func)0)
111 0 : return 1;
112 2606 : state = (struct inflate_state FAR *)strm->state;
113 5212 : if (state == Z_NULL || state->strm != strm ||
114 5212 : state->mode < HEAD || state->mode > SYNC)
115 0 : return 1;
116 2606 : return 0;
117 : }
118 :
119 240 : int ZEXPORT inflateResetKeep(strm)
120 : z_streamp strm;
121 : {
122 : struct inflate_state FAR *state;
123 :
124 240 : if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
125 240 : state = (struct inflate_state FAR *)strm->state;
126 240 : strm->total_in = strm->total_out = state->total = 0;
127 240 : strm->msg = Z_NULL;
128 240 : if (state->wrap) /* to support ill-conceived Java test suite */
129 140 : strm->adler = state->wrap & 1;
130 240 : state->mode = HEAD;
131 240 : state->last = 0;
132 240 : state->havedict = 0;
133 240 : state->dmax = 32768U;
134 240 : state->head = Z_NULL;
135 240 : state->hold = 0;
136 240 : state->bits = 0;
137 240 : state->lencode = state->distcode = state->next = state->codes;
138 240 : state->sane = 1;
139 240 : state->back = -1;
140 : Tracev((stderr, "inflate: reset\n"));
141 240 : return Z_OK;
142 : }
143 :
144 240 : int ZEXPORT inflateReset(strm)
145 : z_streamp strm;
146 : {
147 : struct inflate_state FAR *state;
148 :
149 240 : if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
150 240 : state = (struct inflate_state FAR *)strm->state;
151 240 : state->wsize = 0;
152 240 : state->whave = 0;
153 240 : state->wnext = 0;
154 240 : return inflateResetKeep(strm);
155 : }
156 :
157 206 : int ZEXPORT inflateReset2(strm, windowBits)
158 : z_streamp strm;
159 : int windowBits;
160 : {
161 : int wrap;
162 : struct inflate_state FAR *state;
163 :
164 : /* get the state */
165 206 : if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
166 206 : state = (struct inflate_state FAR *)strm->state;
167 :
168 : /* extract wrap request from windowBits parameter */
169 206 : if (windowBits < 0) {
170 100 : wrap = 0;
171 100 : windowBits = -windowBits;
172 : }
173 : else {
174 106 : wrap = (windowBits >> 4) + 5;
175 : #ifdef GUNZIP
176 106 : if (windowBits < 48)
177 106 : windowBits &= 15;
178 : #endif
179 : }
180 :
181 : /* set number of window bits, free window if different */
182 206 : if (windowBits && (windowBits < 8 || windowBits > 15))
183 0 : return Z_STREAM_ERROR;
184 206 : if (state->window != Z_NULL && state->wbits != (unsigned)windowBits) {
185 0 : ZFREE(strm, state->window);
186 0 : state->window = Z_NULL;
187 : }
188 :
189 : /* update state and reset the rest of it */
190 206 : state->wrap = wrap;
191 206 : state->wbits = (unsigned)windowBits;
192 206 : return inflateReset(strm);
193 : }
194 :
195 206 : int ZEXPORT inflateInit2_(strm, windowBits, version, stream_size)
196 : z_streamp strm;
197 : int windowBits;
198 : const char *version;
199 : int stream_size;
200 : {
201 : int ret;
202 : struct inflate_state FAR *state;
203 :
204 206 : if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
205 : stream_size != (int)(sizeof(z_stream)))
206 0 : return Z_VERSION_ERROR;
207 206 : if (strm == Z_NULL) return Z_STREAM_ERROR;
208 206 : strm->msg = Z_NULL; /* in case we return an error */
209 206 : if (strm->zalloc == (alloc_func)0) {
210 : #ifdef Z_SOLO
211 : return Z_STREAM_ERROR;
212 : #else
213 172 : strm->zalloc = zcalloc;
214 172 : strm->opaque = (voidpf)0;
215 : #endif
216 : }
217 206 : if (strm->zfree == (free_func)0)
218 : #ifdef Z_SOLO
219 : return Z_STREAM_ERROR;
220 : #else
221 172 : strm->zfree = zcfree;
222 : #endif
223 206 : state = (struct inflate_state FAR *)
224 206 : ZALLOC(strm, 1, sizeof(struct inflate_state));
225 206 : if (state == Z_NULL) return Z_MEM_ERROR;
226 : Tracev((stderr, "inflate: allocated\n"));
227 206 : strm->state = (struct internal_state FAR *)state;
228 206 : state->strm = strm;
229 206 : state->window = Z_NULL;
230 206 : state->mode = HEAD; /* to pass state test in inflateReset2() */
231 206 : ret = inflateReset2(strm, windowBits);
232 206 : if (ret != Z_OK) {
233 0 : ZFREE(strm, state);
234 0 : strm->state = Z_NULL;
235 : }
236 206 : return ret;
237 : }
238 :
239 75 : int ZEXPORT inflateInit_(strm, version, stream_size)
240 : z_streamp strm;
241 : const char *version;
242 : int stream_size;
243 : {
244 75 : return inflateInit2_(strm, DEF_WBITS, version, stream_size);
245 : }
246 :
247 0 : int ZEXPORT inflatePrime(strm, bits, value)
248 : z_streamp strm;
249 : int bits;
250 : int value;
251 : {
252 : struct inflate_state FAR *state;
253 :
254 0 : if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
255 0 : state = (struct inflate_state FAR *)strm->state;
256 0 : if (bits < 0) {
257 0 : state->hold = 0;
258 0 : state->bits = 0;
259 0 : return Z_OK;
260 : }
261 0 : if (bits > 16 || state->bits + (uInt)bits > 32) return Z_STREAM_ERROR;
262 0 : value &= (1L << bits) - 1;
263 0 : state->hold += (unsigned)value << state->bits;
264 0 : state->bits += (uInt)bits;
265 0 : return Z_OK;
266 : }
267 :
268 : /*
269 : Return state with length and distance decoding tables and index sizes set to
270 : fixed code decoding. Normally this returns fixed tables from inffixed.h.
271 : If BUILDFIXED is defined, then instead this routine builds the tables the
272 : first time it's called, and returns those tables the first time and
273 : thereafter. This reduces the size of the code by about 2K bytes, in
274 : exchange for a little execution time. However, BUILDFIXED should not be
275 : used for threaded applications, since the rewriting of the tables and virgin
276 : may not be thread-safe.
277 : */
278 149 : local void fixedtables(state)
279 : struct inflate_state FAR *state;
280 : {
281 : #ifdef BUILDFIXED
282 : static int virgin = 1;
283 : static code *lenfix, *distfix;
284 : static code fixed[544];
285 :
286 : /* build fixed huffman tables if first call (may not be thread safe) */
287 : if (virgin) {
288 : unsigned sym, bits;
289 : static code *next;
290 :
291 : /* literal/length table */
292 : sym = 0;
293 : while (sym < 144) state->lens[sym++] = 8;
294 : while (sym < 256) state->lens[sym++] = 9;
295 : while (sym < 280) state->lens[sym++] = 7;
296 : while (sym < 288) state->lens[sym++] = 8;
297 : next = fixed;
298 : lenfix = next;
299 : bits = 9;
300 : inflate_table(LENS, state->lens, 288, &(next), &(bits), state->work);
301 :
302 : /* distance table */
303 : sym = 0;
304 : while (sym < 32) state->lens[sym++] = 5;
305 : distfix = next;
306 : bits = 5;
307 : inflate_table(DISTS, state->lens, 32, &(next), &(bits), state->work);
308 :
309 : /* do this just once */
310 : virgin = 0;
311 : }
312 : #else /* !BUILDFIXED */
313 : # include "inffixed.h"
314 : #endif /* BUILDFIXED */
315 149 : state->lencode = lenfix;
316 149 : state->lenbits = 9;
317 149 : state->distcode = distfix;
318 149 : state->distbits = 5;
319 149 : }
320 :
321 : #ifdef MAKEFIXED
322 : #include <stdio.h>
323 :
324 : /*
325 : Write out the inffixed.h that is #include'd above. Defining MAKEFIXED also
326 : defines BUILDFIXED, so the tables are built on the fly. makefixed() writes
327 : those tables to stdout, which would be piped to inffixed.h. A small program
328 : can simply call makefixed to do this:
329 :
330 : void makefixed(void);
331 :
332 : int main(void)
333 : {
334 : makefixed();
335 : return 0;
336 : }
337 :
338 : Then that can be linked with zlib built with MAKEFIXED defined and run:
339 :
340 : a.out > inffixed.h
341 : */
342 : void makefixed()
343 : {
344 : unsigned low, size;
345 : struct inflate_state state;
346 :
347 : fixedtables(&state);
348 : puts(" /* inffixed.h -- table for decoding fixed codes");
349 : puts(" * Generated automatically by makefixed().");
350 : puts(" */");
351 : puts("");
352 : puts(" /* WARNING: this file should *not* be used by applications.");
353 : puts(" It is part of the implementation of this library and is");
354 : puts(" subject to change. Applications should only use zlib.h.");
355 : puts(" */");
356 : puts("");
357 : size = 1U << 9;
358 : printf(" static const code lenfix[%u] = {", size);
359 : low = 0;
360 : for (;;) {
361 : if ((low % 7) == 0) printf("\n ");
362 : printf("{%u,%u,%d}", (low & 127) == 99 ? 64 : state.lencode[low].op,
363 : state.lencode[low].bits, state.lencode[low].val);
364 : if (++low == size) break;
365 : putchar(',');
366 : }
367 : puts("\n };");
368 : size = 1U << 5;
369 : printf("\n static const code distfix[%u] = {", size);
370 : low = 0;
371 : for (;;) {
372 : if ((low % 6) == 0) printf("\n ");
373 : printf("{%u,%u,%d}", state.distcode[low].op, state.distcode[low].bits,
374 : state.distcode[low].val);
375 : if (++low == size) break;
376 : putchar(',');
377 : }
378 : puts("\n };");
379 : }
380 : #endif /* MAKEFIXED */
381 :
382 : /*
383 : Update the window with the last wsize (normally 32K) bytes written before
384 : returning. If window does not exist yet, create it. This is only called
385 : when a window is already in use, or when output has been written during this
386 : inflate call, but the end of the deflate stream has not been reached yet.
387 : It is also called to create a window for dictionary data when a dictionary
388 : is loaded.
389 :
390 : Providing output buffers larger than 32K to inflate() should provide a speed
391 : advantage, since only the last 32K of output is copied to the sliding window
392 : upon return from inflate(), and since all distances after the first 32K of
393 : output will fall in the output data, making match copies simpler and faster.
394 : The advantage may be dependent on the size of the processor's data caches.
395 : */
396 1639 : local int updatewindow(strm, end, copy)
397 : z_streamp strm;
398 : const Bytef *end;
399 : unsigned copy;
400 : {
401 : struct inflate_state FAR *state;
402 : unsigned dist;
403 :
404 1639 : state = (struct inflate_state FAR *)strm->state;
405 :
406 : /* if it hasn't been done already, allocate space for the window */
407 1639 : if (state->window == Z_NULL) {
408 113 : state->window = (unsigned char FAR *)
409 113 : ZALLOC(strm, 1U << state->wbits,
410 : sizeof(unsigned char));
411 113 : if (state->window == Z_NULL) return 1;
412 : }
413 :
414 : /* if window not in use yet, initialize */
415 1639 : if (state->wsize == 0) {
416 147 : state->wsize = 1U << state->wbits;
417 147 : state->wnext = 0;
418 147 : state->whave = 0;
419 : }
420 :
421 : /* copy state->wsize or less output bytes into the circular window */
422 1639 : if (copy >= state->wsize) {
423 37 : zmemcpy(state->window, end - state->wsize, state->wsize);
424 37 : state->wnext = 0;
425 37 : state->whave = state->wsize;
426 : }
427 : else {
428 1602 : dist = state->wsize - state->wnext;
429 1602 : if (dist > copy) dist = copy;
430 1602 : zmemcpy(state->window + state->wnext, end - copy, dist);
431 1602 : copy -= dist;
432 1602 : if (copy) {
433 0 : zmemcpy(state->window, end - copy, copy);
434 0 : state->wnext = copy;
435 0 : state->whave = state->wsize;
436 : }
437 : else {
438 1602 : state->wnext += dist;
439 1602 : if (state->wnext == state->wsize) state->wnext = 0;
440 1602 : if (state->whave < state->wsize) state->whave += dist;
441 : }
442 : }
443 1639 : return 0;
444 : }
445 :
446 : /* Macros for inflate(): */
447 :
448 : /* check function to use adler32() for zlib or crc32() for gzip */
449 : #ifdef GUNZIP
450 : # define UPDATE(check, buf, len) \
451 : (state->flags ? crc32(check, buf, len) : adler32(check, buf, len))
452 : #else
453 : # define UPDATE(check, buf, len) adler32(check, buf, len)
454 : #endif
455 :
456 : /* check macros for header crc */
457 : #ifdef GUNZIP
458 : # define CRC2(check, word) \
459 : do { \
460 : hbuf[0] = (unsigned char)(word); \
461 : hbuf[1] = (unsigned char)((word) >> 8); \
462 : check = crc32(check, hbuf, 2); \
463 : } while (0)
464 :
465 : # define CRC4(check, word) \
466 : do { \
467 : hbuf[0] = (unsigned char)(word); \
468 : hbuf[1] = (unsigned char)((word) >> 8); \
469 : hbuf[2] = (unsigned char)((word) >> 16); \
470 : hbuf[3] = (unsigned char)((word) >> 24); \
471 : check = crc32(check, hbuf, 4); \
472 : } while (0)
473 : #endif
474 :
475 : /* Load registers with state in inflate() for speed */
476 : #define LOAD() \
477 : do { \
478 : put = strm->next_out; \
479 : left = strm->avail_out; \
480 : next = strm->next_in; \
481 : have = strm->avail_in; \
482 : hold = state->hold; \
483 : bits = state->bits; \
484 : } while (0)
485 :
486 : /* Restore state from registers in inflate() */
487 : #define RESTORE() \
488 : do { \
489 : strm->next_out = put; \
490 : strm->avail_out = left; \
491 : strm->next_in = next; \
492 : strm->avail_in = have; \
493 : state->hold = hold; \
494 : state->bits = bits; \
495 : } while (0)
496 :
497 : /* Clear the input bit accumulator */
498 : #define INITBITS() \
499 : do { \
500 : hold = 0; \
501 : bits = 0; \
502 : } while (0)
503 :
504 : /* Get a byte of input into the bit accumulator, or return from inflate()
505 : if there is no input available. */
506 : #define PULLBYTE() \
507 : do { \
508 : if (have == 0) goto inf_leave; \
509 : have--; \
510 : hold += (unsigned long)(*next++) << bits; \
511 : bits += 8; \
512 : } while (0)
513 :
514 : /* Assure that there are at least n bits in the bit accumulator. If there is
515 : not enough available input to do that, then return from inflate(). */
516 : #define NEEDBITS(n) \
517 : do { \
518 : while (bits < (unsigned)(n)) \
519 : PULLBYTE(); \
520 : } while (0)
521 :
522 : /* Return the low n bits of the bit accumulator (n < 16) */
523 : #define BITS(n) \
524 : ((unsigned)hold & ((1U << (n)) - 1))
525 :
526 : /* Remove n bits from the bit accumulator */
527 : #define DROPBITS(n) \
528 : do { \
529 : hold >>= (n); \
530 : bits -= (unsigned)(n); \
531 : } while (0)
532 :
533 : /* Remove zero to seven bits as needed to go to a byte boundary */
534 : #define BYTEBITS() \
535 : do { \
536 : hold >>= bits & 7; \
537 : bits -= bits & 7; \
538 : } while (0)
539 :
540 : /*
541 : inflate() uses a state machine to process as much input data and generate as
542 : much output data as possible before returning. The state machine is
543 : structured roughly as follows:
544 :
545 : for (;;) switch (state) {
546 : ...
547 : case STATEn:
548 : if (not enough input data or output space to make progress)
549 : return;
550 : ... make progress ...
551 : state = STATEm;
552 : break;
553 : ...
554 : }
555 :
556 : so when inflate() is called again, the same case is attempted again, and
557 : if the appropriate resources are provided, the machine proceeds to the
558 : next state. The NEEDBITS() macro is usually the way the state evaluates
559 : whether it can proceed or should return. NEEDBITS() does the return if
560 : the requested bits are not available. The typical use of the BITS macros
561 : is:
562 :
563 : NEEDBITS(n);
564 : ... do something with BITS(n) ...
565 : DROPBITS(n);
566 :
567 : where NEEDBITS(n) either returns from inflate() if there isn't enough
568 : input left to load n bits into the accumulator, or it continues. BITS(n)
569 : gives the low n bits in the accumulator. When done, DROPBITS(n) drops
570 : the low n bits off the accumulator. INITBITS() clears the accumulator
571 : and sets the number of available bits to zero. BYTEBITS() discards just
572 : enough bits to put the accumulator on a byte boundary. After BYTEBITS()
573 : and a NEEDBITS(8), then BITS(8) would return the next byte in the stream.
574 :
575 : NEEDBITS(n) uses PULLBYTE() to get an available byte of input, or to return
576 : if there is no input available. The decoding of variable length codes uses
577 : PULLBYTE() directly in order to pull just enough bytes to decode the next
578 : code, and no more.
579 :
580 : Some states loop until they get enough input, making sure that enough
581 : state information is maintained to continue the loop where it left off
582 : if NEEDBITS() returns in the loop. For example, want, need, and keep
583 : would all have to actually be part of the saved state in case NEEDBITS()
584 : returns:
585 :
586 : case STATEw:
587 : while (want < need) {
588 : NEEDBITS(n);
589 : keep[want++] = BITS(n);
590 : DROPBITS(n);
591 : }
592 : state = STATEx;
593 : case STATEx:
594 :
595 : As shown above, if the next state is also the next case, then the break
596 : is omitted.
597 :
598 : A state may also return if there is not enough output space available to
599 : complete that state. Those states are copying stored data, writing a
600 : literal byte, and copying a matching string.
601 :
602 : When returning, a "goto inf_leave" is used to update the total counters,
603 : update the check value, and determine whether any progress has been made
604 : during that inflate() call in order to return the proper return code.
605 : Progress is defined as a change in either strm->avail_in or strm->avail_out.
606 : When there is a window, goto inf_leave will update the window with the last
607 : output written. If a goto inf_leave occurs in the middle of decompression
608 : and there is no window currently, goto inf_leave will create one and copy
609 : output to the window for the next call of inflate().
610 :
611 : In this implementation, the flush parameter of inflate() only affects the
612 : return code (per zlib.h). inflate() always writes as much as possible to
613 : strm->next_out, given the space available and the provided input--the effect
614 : documented in zlib.h of Z_SYNC_FLUSH. Furthermore, inflate() always defers
615 : the allocation of and copying into a sliding window until necessary, which
616 : provides the effect documented in zlib.h for Z_FINISH when the entire input
617 : stream available. So the only thing the flush parameter actually does is:
618 : when flush is set to Z_FINISH, inflate() cannot return Z_OK. Instead it
619 : will return Z_BUF_ERROR if it has not reached the end of the stream.
620 : */
621 :
622 1714 : int ZEXPORT inflate(strm, flush)
623 : z_streamp strm;
624 : int flush;
625 : {
626 : struct inflate_state FAR *state;
627 : z_const unsigned char FAR *next; /* next input */
628 : unsigned char FAR *put; /* next output */
629 : unsigned have, left; /* available input and output */
630 : unsigned long hold; /* bit buffer */
631 : unsigned bits; /* bits in bit buffer */
632 : unsigned in, out; /* save starting available input and output */
633 : unsigned copy; /* number of stored or match bytes to copy */
634 : unsigned char FAR *from; /* where to copy match bytes from */
635 : code here; /* current decoding table entry */
636 : code last; /* parent table entry */
637 : unsigned len; /* length to copy for repeats, bits to drop */
638 : int ret; /* return code */
639 : #ifdef GUNZIP
640 : unsigned char hbuf[4]; /* buffer for gzip header crc calculation */
641 : #endif
642 : static const unsigned short order[19] = /* permutation of code lengths */
643 : {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
644 :
645 3428 : if (inflateStateCheck(strm) || strm->next_out == Z_NULL ||
646 1714 : (strm->next_in == Z_NULL && strm->avail_in != 0))
647 0 : return Z_STREAM_ERROR;
648 :
649 1714 : state = (struct inflate_state FAR *)strm->state;
650 1714 : if (state->mode == TYPE) state->mode = TYPEDO; /* skip check */
651 1714 : LOAD();
652 1714 : in = have;
653 1714 : out = left;
654 1714 : ret = Z_OK;
655 : for (;;)
656 223480 : switch (state->mode) {
657 : case HEAD:
658 213 : if (state->wrap == 0) {
659 91 : state->mode = TYPEDO;
660 91 : break;
661 : }
662 122 : NEEDBITS(16);
663 : #ifdef GUNZIP
664 122 : if ((state->wrap & 2) && hold == 0x8b1f) { /* gzip header */
665 0 : if (state->wbits == 0)
666 0 : state->wbits = 15;
667 0 : state->check = crc32(0L, Z_NULL, 0);
668 0 : CRC2(state->check, hold);
669 0 : INITBITS();
670 0 : state->mode = FLAGS;
671 0 : break;
672 : }
673 122 : state->flags = 0; /* expect zlib header */
674 122 : if (state->head != Z_NULL)
675 0 : state->head->done = -1;
676 244 : if (!(state->wrap & 1) || /* check if zlib header allowed */
677 : #else
678 : if (
679 : #endif
680 122 : ((BITS(8) << 8) + (hold >> 8)) % 31) {
681 0 : strm->msg = (char *)"incorrect header check";
682 0 : state->mode = BAD;
683 0 : break;
684 : }
685 122 : if (BITS(4) != Z_DEFLATED) {
686 0 : strm->msg = (char *)"unknown compression method";
687 0 : state->mode = BAD;
688 0 : break;
689 : }
690 122 : DROPBITS(4);
691 122 : len = BITS(4) + 8;
692 122 : if (state->wbits == 0)
693 0 : state->wbits = len;
694 122 : if (len > 15 || len > state->wbits) {
695 0 : strm->msg = (char *)"invalid window size";
696 0 : state->mode = BAD;
697 0 : break;
698 : }
699 122 : state->dmax = 1U << len;
700 : Tracev((stderr, "inflate: zlib header ok\n"));
701 122 : strm->adler = state->check = adler32(0L, Z_NULL, 0);
702 122 : state->mode = hold & 0x200 ? DICTID : TYPE;
703 122 : INITBITS();
704 122 : break;
705 : #ifdef GUNZIP
706 : case FLAGS:
707 0 : NEEDBITS(16);
708 0 : state->flags = (int)(hold);
709 0 : if ((state->flags & 0xff) != Z_DEFLATED) {
710 0 : strm->msg = (char *)"unknown compression method";
711 0 : state->mode = BAD;
712 0 : break;
713 : }
714 0 : if (state->flags & 0xe000) {
715 0 : strm->msg = (char *)"unknown header flags set";
716 0 : state->mode = BAD;
717 0 : break;
718 : }
719 0 : if (state->head != Z_NULL)
720 0 : state->head->text = (int)((hold >> 8) & 1);
721 0 : if ((state->flags & 0x0200) && (state->wrap & 4))
722 0 : CRC2(state->check, hold);
723 0 : INITBITS();
724 0 : state->mode = TIME;
725 : case TIME:
726 0 : NEEDBITS(32);
727 0 : if (state->head != Z_NULL)
728 0 : state->head->time = hold;
729 0 : if ((state->flags & 0x0200) && (state->wrap & 4))
730 0 : CRC4(state->check, hold);
731 0 : INITBITS();
732 0 : state->mode = OS;
733 : case OS:
734 0 : NEEDBITS(16);
735 0 : if (state->head != Z_NULL) {
736 0 : state->head->xflags = (int)(hold & 0xff);
737 0 : state->head->os = (int)(hold >> 8);
738 : }
739 0 : if ((state->flags & 0x0200) && (state->wrap & 4))
740 0 : CRC2(state->check, hold);
741 0 : INITBITS();
742 0 : state->mode = EXLEN;
743 : case EXLEN:
744 0 : if (state->flags & 0x0400) {
745 0 : NEEDBITS(16);
746 0 : state->length = (unsigned)(hold);
747 0 : if (state->head != Z_NULL)
748 0 : state->head->extra_len = (unsigned)hold;
749 0 : if ((state->flags & 0x0200) && (state->wrap & 4))
750 0 : CRC2(state->check, hold);
751 0 : INITBITS();
752 : }
753 0 : else if (state->head != Z_NULL)
754 0 : state->head->extra = Z_NULL;
755 0 : state->mode = EXTRA;
756 : case EXTRA:
757 0 : if (state->flags & 0x0400) {
758 0 : copy = state->length;
759 0 : if (copy > have) copy = have;
760 0 : if (copy) {
761 0 : if (state->head != Z_NULL &&
762 0 : state->head->extra != Z_NULL) {
763 0 : len = state->head->extra_len - state->length;
764 0 : zmemcpy(state->head->extra + len, next,
765 0 : len + copy > state->head->extra_max ?
766 0 : state->head->extra_max - len : copy);
767 : }
768 0 : if ((state->flags & 0x0200) && (state->wrap & 4))
769 0 : state->check = crc32(state->check, next, copy);
770 0 : have -= copy;
771 0 : next += copy;
772 0 : state->length -= copy;
773 : }
774 0 : if (state->length) goto inf_leave;
775 : }
776 0 : state->length = 0;
777 0 : state->mode = NAME;
778 : case NAME:
779 0 : if (state->flags & 0x0800) {
780 0 : if (have == 0) goto inf_leave;
781 0 : copy = 0;
782 : do {
783 0 : len = (unsigned)(next[copy++]);
784 0 : if (state->head != Z_NULL &&
785 0 : state->head->name != Z_NULL &&
786 0 : state->length < state->head->name_max)
787 0 : state->head->name[state->length++] = (Bytef)len;
788 0 : } while (len && copy < have);
789 0 : if ((state->flags & 0x0200) && (state->wrap & 4))
790 0 : state->check = crc32(state->check, next, copy);
791 0 : have -= copy;
792 0 : next += copy;
793 0 : if (len) goto inf_leave;
794 : }
795 0 : else if (state->head != Z_NULL)
796 0 : state->head->name = Z_NULL;
797 0 : state->length = 0;
798 0 : state->mode = COMMENT;
799 : case COMMENT:
800 0 : if (state->flags & 0x1000) {
801 0 : if (have == 0) goto inf_leave;
802 0 : copy = 0;
803 : do {
804 0 : len = (unsigned)(next[copy++]);
805 0 : if (state->head != Z_NULL &&
806 0 : state->head->comment != Z_NULL &&
807 0 : state->length < state->head->comm_max)
808 0 : state->head->comment[state->length++] = (Bytef)len;
809 0 : } while (len && copy < have);
810 0 : if ((state->flags & 0x0200) && (state->wrap & 4))
811 0 : state->check = crc32(state->check, next, copy);
812 0 : have -= copy;
813 0 : next += copy;
814 0 : if (len) goto inf_leave;
815 : }
816 0 : else if (state->head != Z_NULL)
817 0 : state->head->comment = Z_NULL;
818 0 : state->mode = HCRC;
819 : case HCRC:
820 0 : if (state->flags & 0x0200) {
821 0 : NEEDBITS(16);
822 0 : if ((state->wrap & 4) && hold != (state->check & 0xffff)) {
823 0 : strm->msg = (char *)"header crc mismatch";
824 0 : state->mode = BAD;
825 0 : break;
826 : }
827 0 : INITBITS();
828 : }
829 0 : if (state->head != Z_NULL) {
830 0 : state->head->hcrc = (int)((state->flags >> 9) & 1);
831 0 : state->head->done = 1;
832 : }
833 0 : strm->adler = state->check = crc32(0L, Z_NULL, 0);
834 0 : state->mode = TYPE;
835 0 : break;
836 : #endif
837 : case DICTID:
838 0 : NEEDBITS(32);
839 0 : strm->adler = state->check = ZSWAP32(hold);
840 0 : INITBITS();
841 0 : state->mode = DICT;
842 : case DICT:
843 0 : if (state->havedict == 0) {
844 0 : RESTORE();
845 0 : return Z_NEED_DICT;
846 : }
847 0 : strm->adler = state->check = adler32(0L, Z_NULL, 0);
848 0 : state->mode = TYPE;
849 : case TYPE:
850 445 : if (flush == Z_BLOCK || flush == Z_TREES) goto inf_leave;
851 : case TYPEDO:
852 546 : if (state->last) {
853 222 : BYTEBITS();
854 222 : state->mode = CHECK;
855 222 : break;
856 : }
857 324 : NEEDBITS(3);
858 324 : state->last = BITS(1);
859 324 : DROPBITS(1);
860 324 : switch (BITS(2)) {
861 : case 0: /* stored block */
862 : Tracev((stderr, "inflate: stored block%s\n",
863 : state->last ? " (last)" : ""));
864 0 : state->mode = STORED;
865 0 : break;
866 : case 1: /* fixed block */
867 149 : fixedtables(state);
868 : Tracev((stderr, "inflate: fixed codes block%s\n",
869 : state->last ? " (last)" : ""));
870 149 : state->mode = LEN_; /* decode codes */
871 149 : if (flush == Z_TREES) {
872 0 : DROPBITS(2);
873 0 : goto inf_leave;
874 : }
875 149 : break;
876 : case 2: /* dynamic block */
877 : Tracev((stderr, "inflate: dynamic codes block%s\n",
878 : state->last ? " (last)" : ""));
879 175 : state->mode = TABLE;
880 175 : break;
881 : case 3:
882 0 : strm->msg = (char *)"invalid block type";
883 0 : state->mode = BAD;
884 : }
885 324 : DROPBITS(2);
886 324 : break;
887 : case STORED:
888 0 : BYTEBITS(); /* go to byte boundary */
889 0 : NEEDBITS(32);
890 0 : if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) {
891 0 : strm->msg = (char *)"invalid stored block lengths";
892 0 : state->mode = BAD;
893 0 : break;
894 : }
895 0 : state->length = (unsigned)hold & 0xffff;
896 : Tracev((stderr, "inflate: stored length %u\n",
897 : state->length));
898 0 : INITBITS();
899 0 : state->mode = COPY_;
900 0 : if (flush == Z_TREES) goto inf_leave;
901 : case COPY_:
902 0 : state->mode = COPY;
903 : case COPY:
904 0 : copy = state->length;
905 0 : if (copy) {
906 0 : if (copy > have) copy = have;
907 0 : if (copy > left) copy = left;
908 0 : if (copy == 0) goto inf_leave;
909 0 : zmemcpy(put, next, copy);
910 0 : have -= copy;
911 0 : next += copy;
912 0 : left -= copy;
913 0 : put += copy;
914 0 : state->length -= copy;
915 0 : break;
916 : }
917 : Tracev((stderr, "inflate: stored end\n"));
918 0 : state->mode = TYPE;
919 0 : break;
920 : case TABLE:
921 175 : NEEDBITS(14);
922 175 : state->nlen = BITS(5) + 257;
923 175 : DROPBITS(5);
924 175 : state->ndist = BITS(5) + 1;
925 175 : DROPBITS(5);
926 175 : state->ncode = BITS(4) + 4;
927 175 : DROPBITS(4);
928 : #ifndef PKZIP_BUG_WORKAROUND
929 175 : if (state->nlen > 286 || state->ndist > 30) {
930 0 : strm->msg = (char *)"too many length or distance symbols";
931 0 : state->mode = BAD;
932 0 : break;
933 : }
934 : #endif
935 : Tracev((stderr, "inflate: table sizes ok\n"));
936 175 : state->have = 0;
937 175 : state->mode = LENLENS;
938 : case LENLENS:
939 3067 : while (state->have < state->ncode) {
940 2717 : NEEDBITS(3);
941 2717 : state->lens[order[state->have++]] = (unsigned short)BITS(3);
942 2717 : DROPBITS(3);
943 : }
944 958 : while (state->have < 19)
945 608 : state->lens[order[state->have++]] = 0;
946 175 : state->next = state->codes;
947 175 : state->lencode = (const code FAR *)(state->next);
948 175 : state->lenbits = 7;
949 175 : ret = inflate_table(CODES, state->lens, 19, &(state->next),
950 175 : &(state->lenbits), state->work);
951 175 : if (ret) {
952 0 : strm->msg = (char *)"invalid code lengths set";
953 0 : state->mode = BAD;
954 0 : break;
955 : }
956 : Tracev((stderr, "inflate: code lengths ok\n"));
957 175 : state->have = 0;
958 175 : state->mode = CODELENS;
959 : case CODELENS:
960 42332 : while (state->have < state->nlen + state->ndist) {
961 : for (;;) {
962 76402 : here = state->lencode[BITS(state->lenbits)];
963 59192 : if ((unsigned)(here.bits) <= bits) break;
964 17210 : PULLBYTE();
965 : }
966 41982 : if (here.val < 16) {
967 39607 : DROPBITS(here.bits);
968 39607 : state->lens[state->have++] = here.val;
969 : }
970 : else {
971 2375 : if (here.val == 16) {
972 1389 : NEEDBITS(here.bits + 2);
973 1389 : DROPBITS(here.bits);
974 1389 : if (state->have == 0) {
975 0 : strm->msg = (char *)"invalid bit length repeat";
976 0 : state->mode = BAD;
977 0 : break;
978 : }
979 1389 : len = state->lens[state->have - 1];
980 1389 : copy = 3 + BITS(2);
981 1389 : DROPBITS(2);
982 : }
983 986 : else if (here.val == 17) {
984 832 : NEEDBITS(here.bits + 3);
985 832 : DROPBITS(here.bits);
986 832 : len = 0;
987 832 : copy = 3 + BITS(3);
988 832 : DROPBITS(3);
989 : }
990 : else {
991 154 : NEEDBITS(here.bits + 7);
992 154 : DROPBITS(here.bits);
993 154 : len = 0;
994 154 : copy = 11 + BITS(7);
995 154 : DROPBITS(7);
996 : }
997 2375 : if (state->have + copy > state->nlen + state->ndist) {
998 0 : strm->msg = (char *)"invalid bit length repeat";
999 0 : state->mode = BAD;
1000 0 : break;
1001 : }
1002 18868 : while (copy--)
1003 14118 : state->lens[state->have++] = (unsigned short)len;
1004 : }
1005 : }
1006 :
1007 : /* handle error breaks in while */
1008 175 : if (state->mode == BAD) break;
1009 :
1010 : /* check for end-of-block code (better have one) */
1011 175 : if (state->lens[256] == 0) {
1012 0 : strm->msg = (char *)"invalid code -- missing end-of-block";
1013 0 : state->mode = BAD;
1014 0 : break;
1015 : }
1016 :
1017 : /* build code tables -- note: do not change the lenbits or distbits
1018 : values here (9 and 6) without reading the comments in inftrees.h
1019 : concerning the ENOUGH constants, which depend on those values */
1020 175 : state->next = state->codes;
1021 175 : state->lencode = (const code FAR *)(state->next);
1022 175 : state->lenbits = 9;
1023 175 : ret = inflate_table(LENS, state->lens, state->nlen, &(state->next),
1024 175 : &(state->lenbits), state->work);
1025 175 : if (ret) {
1026 0 : strm->msg = (char *)"invalid literal/lengths set";
1027 0 : state->mode = BAD;
1028 0 : break;
1029 : }
1030 175 : state->distcode = (const code FAR *)(state->next);
1031 175 : state->distbits = 6;
1032 175 : ret = inflate_table(DISTS, state->lens + state->nlen, state->ndist,
1033 175 : &(state->next), &(state->distbits), state->work);
1034 175 : if (ret) {
1035 0 : strm->msg = (char *)"invalid distances set";
1036 0 : state->mode = BAD;
1037 0 : break;
1038 : }
1039 : Tracev((stderr, "inflate: codes ok\n"));
1040 175 : state->mode = LEN_;
1041 175 : if (flush == Z_TREES) goto inf_leave;
1042 : case LEN_:
1043 324 : state->mode = LEN;
1044 : case LEN:
1045 65517 : if (have >= 6 && left >= 258) {
1046 197 : RESTORE();
1047 197 : inflate_fast(strm, out);
1048 197 : LOAD();
1049 197 : if (state->mode == TYPE)
1050 28 : state->back = -1;
1051 197 : break;
1052 : }
1053 65320 : state->back = 0;
1054 : for (;;) {
1055 163108 : here = state->lencode[BITS(state->lenbits)];
1056 114214 : if ((unsigned)(here.bits) <= bits) break;
1057 48894 : PULLBYTE();
1058 : }
1059 65320 : if (here.op && (here.op & 0xf0) == 0) {
1060 3505 : last = here;
1061 : for (;;) {
1062 8714 : here = state->lencode[last.val +
1063 4073 : (BITS(last.bits + last.op) >> last.bits)];
1064 4073 : if ((unsigned)(last.bits + here.bits) <= bits) break;
1065 568 : PULLBYTE();
1066 : }
1067 3505 : DROPBITS(last.bits);
1068 3505 : state->back += last.bits;
1069 : }
1070 65320 : DROPBITS(here.bits);
1071 65320 : state->back += here.bits;
1072 65320 : state->length = (unsigned)here.val;
1073 65320 : if ((int)(here.op) == 0) {
1074 : Tracevv((stderr, here.val >= 0x20 && here.val < 0x7f ?
1075 : "inflate: literal '%c'\n" :
1076 : "inflate: literal 0x%02x\n", here.val));
1077 43663 : state->mode = LIT;
1078 43663 : break;
1079 : }
1080 21657 : if (here.op & 32) {
1081 : Tracevv((stderr, "inflate: end of block\n"));
1082 296 : state->back = -1;
1083 296 : state->mode = TYPE;
1084 296 : break;
1085 : }
1086 21361 : if (here.op & 64) {
1087 0 : strm->msg = (char *)"invalid literal/length code";
1088 0 : state->mode = BAD;
1089 0 : break;
1090 : }
1091 21361 : state->extra = (unsigned)(here.op) & 15;
1092 21361 : state->mode = LENEXT;
1093 : case LENEXT:
1094 21361 : if (state->extra) {
1095 3262 : NEEDBITS(state->extra);
1096 3262 : state->length += BITS(state->extra);
1097 3262 : DROPBITS(state->extra);
1098 3262 : state->back += state->extra;
1099 : }
1100 : Tracevv((stderr, "inflate: length %u\n", state->length));
1101 21361 : state->was = state->length;
1102 21361 : state->mode = DIST;
1103 : case DIST:
1104 : for (;;) {
1105 43035 : here = state->distcode[BITS(state->distbits)];
1106 32198 : if ((unsigned)(here.bits) <= bits) break;
1107 10837 : PULLBYTE();
1108 : }
1109 21361 : if ((here.op & 0xf0) == 0) {
1110 554 : last = here;
1111 : for (;;) {
1112 1342 : here = state->distcode[last.val +
1113 632 : (BITS(last.bits + last.op) >> last.bits)];
1114 632 : if ((unsigned)(last.bits + here.bits) <= bits) break;
1115 78 : PULLBYTE();
1116 : }
1117 554 : DROPBITS(last.bits);
1118 554 : state->back += last.bits;
1119 : }
1120 21361 : DROPBITS(here.bits);
1121 21361 : state->back += here.bits;
1122 21361 : if (here.op & 64) {
1123 0 : strm->msg = (char *)"invalid distance code";
1124 0 : state->mode = BAD;
1125 0 : break;
1126 : }
1127 21361 : state->offset = (unsigned)here.val;
1128 21361 : state->extra = (unsigned)(here.op) & 15;
1129 21361 : state->mode = DISTEXT;
1130 : case DISTEXT:
1131 21362 : if (state->extra) {
1132 19559 : NEEDBITS(state->extra);
1133 19558 : state->offset += BITS(state->extra);
1134 19558 : DROPBITS(state->extra);
1135 19558 : state->back += state->extra;
1136 : }
1137 : #ifdef INFLATE_STRICT
1138 : if (state->offset > state->dmax) {
1139 : strm->msg = (char *)"invalid distance too far back";
1140 : state->mode = BAD;
1141 : break;
1142 : }
1143 : #endif
1144 : Tracevv((stderr, "inflate: distance %u\n", state->offset));
1145 21361 : state->mode = MATCH;
1146 : case MATCH:
1147 23313 : if (left == 0) goto inf_leave;
1148 22306 : copy = out - left;
1149 22306 : if (state->offset > copy) { /* copy from window */
1150 15172 : copy = state->offset - copy;
1151 15172 : if (copy > state->whave) {
1152 0 : if (state->sane) {
1153 0 : strm->msg = (char *)"invalid distance too far back";
1154 0 : state->mode = BAD;
1155 0 : break;
1156 : }
1157 : #ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR
1158 : Trace((stderr, "inflate.c too far\n"));
1159 : copy -= state->whave;
1160 : if (copy > state->length) copy = state->length;
1161 : if (copy > left) copy = left;
1162 : left -= copy;
1163 : state->length -= copy;
1164 : do {
1165 : *put++ = 0;
1166 : } while (--copy);
1167 : if (state->length == 0) state->mode = LEN;
1168 : break;
1169 : #endif
1170 : }
1171 15172 : if (copy > state->wnext) {
1172 0 : copy -= state->wnext;
1173 0 : from = state->window + (state->wsize - copy);
1174 : }
1175 : else
1176 15172 : from = state->window + (state->wnext - copy);
1177 15172 : if (copy > state->length) copy = state->length;
1178 : }
1179 : else { /* copy from output */
1180 7134 : from = put - state->offset;
1181 7134 : copy = state->length;
1182 : }
1183 22306 : if (copy > left) copy = left;
1184 22306 : left -= copy;
1185 22306 : state->length -= copy;
1186 : do {
1187 195567 : *put++ = *from++;
1188 195567 : } while (--copy);
1189 22306 : if (state->length == 0) state->mode = LEN;
1190 22306 : break;
1191 : case LIT:
1192 44147 : if (left == 0) goto inf_leave;
1193 43662 : *put++ = (unsigned char)(state->length);
1194 43662 : left--;
1195 43662 : state->mode = LEN;
1196 43662 : break;
1197 : case CHECK:
1198 222 : if (state->wrap) {
1199 122 : NEEDBITS(32);
1200 122 : out -= left;
1201 122 : strm->total_out += out;
1202 122 : state->total += out;
1203 122 : if ((state->wrap & 4) && out)
1204 50 : strm->adler = state->check =
1205 50 : UPDATE(state->check, put - out, out);
1206 122 : out = left;
1207 244 : if ((state->wrap & 4) && (
1208 : #ifdef GUNZIP
1209 244 : state->flags ? hold :
1210 : #endif
1211 244 : ZSWAP32(hold)) != state->check) {
1212 0 : strm->msg = (char *)"incorrect data check";
1213 0 : state->mode = BAD;
1214 0 : break;
1215 : }
1216 122 : INITBITS();
1217 : Tracev((stderr, "inflate: check matches trailer\n"));
1218 : }
1219 : #ifdef GUNZIP
1220 222 : state->mode = LENGTH;
1221 : case LENGTH:
1222 222 : if (state->wrap && state->flags) {
1223 0 : NEEDBITS(32);
1224 0 : if (hold != (state->total & 0xffffffffUL)) {
1225 0 : strm->msg = (char *)"incorrect length check";
1226 0 : state->mode = BAD;
1227 0 : break;
1228 : }
1229 0 : INITBITS();
1230 : Tracev((stderr, "inflate: length matches trailer\n"));
1231 : }
1232 : #endif
1233 222 : state->mode = DONE;
1234 : case DONE:
1235 222 : ret = Z_STREAM_END;
1236 222 : goto inf_leave;
1237 : case BAD:
1238 0 : ret = Z_DATA_ERROR;
1239 0 : goto inf_leave;
1240 : case MEM:
1241 0 : return Z_MEM_ERROR;
1242 : case SYNC:
1243 : default:
1244 0 : return Z_STREAM_ERROR;
1245 : }
1246 :
1247 : /*
1248 : Return from inflate(), updating the total counts and the check value.
1249 : If there was no progress during the inflate() call, return a buffer
1250 : error. Call updatewindow() to create and/or update the window state.
1251 : Note: a memory error from inflate() is non-recoverable.
1252 : */
1253 : inf_leave:
1254 1714 : RESTORE();
1255 1861 : if (state->wsize || (out != strm->avail_out && state->mode < BAD &&
1256 247 : (state->mode < CHECK || flush != Z_FINISH)))
1257 1639 : if (updatewindow(strm, strm->next_out, out - strm->avail_out)) {
1258 0 : state->mode = MEM;
1259 0 : return Z_MEM_ERROR;
1260 : }
1261 1714 : in -= strm->avail_in;
1262 1714 : out -= strm->avail_out;
1263 1714 : strm->total_in += in;
1264 1714 : strm->total_out += out;
1265 1714 : state->total += out;
1266 1714 : if ((state->wrap & 4) && out)
1267 1492 : strm->adler = state->check =
1268 1492 : UPDATE(state->check, strm->next_out - out, out);
1269 5142 : strm->data_type = (int)state->bits + (state->last ? 64 : 0) +
1270 3428 : (state->mode == TYPE ? 128 : 0) +
1271 1714 : (state->mode == LEN_ || state->mode == COPY_ ? 256 : 0);
1272 1714 : if (((in == 0 && out == 0) || flush == Z_FINISH) && ret == Z_OK)
1273 0 : ret = Z_BUF_ERROR;
1274 1714 : return ret;
1275 : }
1276 :
1277 206 : int ZEXPORT inflateEnd(strm)
1278 : z_streamp strm;
1279 : {
1280 : struct inflate_state FAR *state;
1281 206 : if (inflateStateCheck(strm))
1282 0 : return Z_STREAM_ERROR;
1283 206 : state = (struct inflate_state FAR *)strm->state;
1284 206 : if (state->window != Z_NULL) ZFREE(strm, state->window);
1285 206 : ZFREE(strm, strm->state);
1286 206 : strm->state = Z_NULL;
1287 : Tracev((stderr, "inflate: end\n"));
1288 206 : return Z_OK;
1289 : }
1290 :
1291 0 : int ZEXPORT inflateGetDictionary(strm, dictionary, dictLength)
1292 : z_streamp strm;
1293 : Bytef *dictionary;
1294 : uInt *dictLength;
1295 : {
1296 : struct inflate_state FAR *state;
1297 :
1298 : /* check state */
1299 0 : if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
1300 0 : state = (struct inflate_state FAR *)strm->state;
1301 :
1302 : /* copy dictionary */
1303 0 : if (state->whave && dictionary != Z_NULL) {
1304 0 : zmemcpy(dictionary, state->window + state->wnext,
1305 0 : state->whave - state->wnext);
1306 0 : zmemcpy(dictionary + state->whave - state->wnext,
1307 0 : state->window, state->wnext);
1308 : }
1309 0 : if (dictLength != Z_NULL)
1310 0 : *dictLength = state->whave;
1311 0 : return Z_OK;
1312 : }
1313 :
1314 0 : int ZEXPORT inflateSetDictionary(strm, dictionary, dictLength)
1315 : z_streamp strm;
1316 : const Bytef *dictionary;
1317 : uInt dictLength;
1318 : {
1319 : struct inflate_state FAR *state;
1320 : unsigned long dictid;
1321 : int ret;
1322 :
1323 : /* check state */
1324 0 : if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
1325 0 : state = (struct inflate_state FAR *)strm->state;
1326 0 : if (state->wrap != 0 && state->mode != DICT)
1327 0 : return Z_STREAM_ERROR;
1328 :
1329 : /* check for correct dictionary identifier */
1330 0 : if (state->mode == DICT) {
1331 0 : dictid = adler32(0L, Z_NULL, 0);
1332 0 : dictid = adler32(dictid, dictionary, dictLength);
1333 0 : if (dictid != state->check)
1334 0 : return Z_DATA_ERROR;
1335 : }
1336 :
1337 : /* copy dictionary to window using updatewindow(), which will amend the
1338 : existing dictionary if appropriate */
1339 0 : ret = updatewindow(strm, dictionary + dictLength, dictLength);
1340 0 : if (ret) {
1341 0 : state->mode = MEM;
1342 0 : return Z_MEM_ERROR;
1343 : }
1344 0 : state->havedict = 1;
1345 : Tracev((stderr, "inflate: dictionary set\n"));
1346 0 : return Z_OK;
1347 : }
1348 :
1349 0 : int ZEXPORT inflateGetHeader(strm, head)
1350 : z_streamp strm;
1351 : gz_headerp head;
1352 : {
1353 : struct inflate_state FAR *state;
1354 :
1355 : /* check state */
1356 0 : if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
1357 0 : state = (struct inflate_state FAR *)strm->state;
1358 0 : if ((state->wrap & 2) == 0) return Z_STREAM_ERROR;
1359 :
1360 : /* save header structure */
1361 0 : state->head = head;
1362 0 : head->done = 0;
1363 0 : return Z_OK;
1364 : }
1365 :
1366 : /*
1367 : Search buf[0..len-1] for the pattern: 0, 0, 0xff, 0xff. Return when found
1368 : or when out of input. When called, *have is the number of pattern bytes
1369 : found in order so far, in 0..3. On return *have is updated to the new
1370 : state. If on return *have equals four, then the pattern was found and the
1371 : return value is how many bytes were read including the last byte of the
1372 : pattern. If *have is less than four, then the pattern has not been found
1373 : yet and the return value is len. In the latter case, syncsearch() can be
1374 : called again with more data and the *have state. *have is initialized to
1375 : zero for the first call.
1376 : */
1377 0 : local unsigned syncsearch(have, buf, len)
1378 : unsigned FAR *have;
1379 : const unsigned char FAR *buf;
1380 : unsigned len;
1381 : {
1382 : unsigned got;
1383 : unsigned next;
1384 :
1385 0 : got = *have;
1386 0 : next = 0;
1387 0 : while (next < len && got < 4) {
1388 0 : if ((int)(buf[next]) == (got < 2 ? 0 : 0xff))
1389 0 : got++;
1390 0 : else if (buf[next])
1391 0 : got = 0;
1392 : else
1393 0 : got = 4 - got;
1394 0 : next++;
1395 : }
1396 0 : *have = got;
1397 0 : return next;
1398 : }
1399 :
1400 0 : int ZEXPORT inflateSync(strm)
1401 : z_streamp strm;
1402 : {
1403 : unsigned len; /* number of bytes to look at or looked at */
1404 : unsigned long in, out; /* temporary to save total_in and total_out */
1405 : unsigned char buf[4]; /* to restore bit buffer to byte string */
1406 : struct inflate_state FAR *state;
1407 :
1408 : /* check parameters */
1409 0 : if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
1410 0 : state = (struct inflate_state FAR *)strm->state;
1411 0 : if (strm->avail_in == 0 && state->bits < 8) return Z_BUF_ERROR;
1412 :
1413 : /* if first time, start search in bit buffer */
1414 0 : if (state->mode != SYNC) {
1415 0 : state->mode = SYNC;
1416 0 : state->hold <<= state->bits & 7;
1417 0 : state->bits -= state->bits & 7;
1418 0 : len = 0;
1419 0 : while (state->bits >= 8) {
1420 0 : buf[len++] = (unsigned char)(state->hold);
1421 0 : state->hold >>= 8;
1422 0 : state->bits -= 8;
1423 : }
1424 0 : state->have = 0;
1425 0 : syncsearch(&(state->have), buf, len);
1426 : }
1427 :
1428 : /* search available input */
1429 0 : len = syncsearch(&(state->have), strm->next_in, strm->avail_in);
1430 0 : strm->avail_in -= len;
1431 0 : strm->next_in += len;
1432 0 : strm->total_in += len;
1433 :
1434 : /* return no joy or set up to restart inflate() on a new block */
1435 0 : if (state->have != 4) return Z_DATA_ERROR;
1436 0 : in = strm->total_in; out = strm->total_out;
1437 0 : inflateReset(strm);
1438 0 : strm->total_in = in; strm->total_out = out;
1439 0 : state->mode = TYPE;
1440 0 : return Z_OK;
1441 : }
1442 :
1443 : /*
1444 : Returns true if inflate is currently at the end of a block generated by
1445 : Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
1446 : implementation to provide an additional safety check. PPP uses
1447 : Z_SYNC_FLUSH but removes the length bytes of the resulting empty stored
1448 : block. When decompressing, PPP checks that at the end of input packet,
1449 : inflate is waiting for these length bytes.
1450 : */
1451 0 : int ZEXPORT inflateSyncPoint(strm)
1452 : z_streamp strm;
1453 : {
1454 : struct inflate_state FAR *state;
1455 :
1456 0 : if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
1457 0 : state = (struct inflate_state FAR *)strm->state;
1458 0 : return state->mode == STORED && state->bits == 0;
1459 : }
1460 :
1461 0 : int ZEXPORT inflateCopy(dest, source)
1462 : z_streamp dest;
1463 : z_streamp source;
1464 : {
1465 : struct inflate_state FAR *state;
1466 : struct inflate_state FAR *copy;
1467 : unsigned char FAR *window;
1468 : unsigned wsize;
1469 :
1470 : /* check input */
1471 0 : if (inflateStateCheck(source) || dest == Z_NULL)
1472 0 : return Z_STREAM_ERROR;
1473 0 : state = (struct inflate_state FAR *)source->state;
1474 :
1475 : /* allocate space */
1476 0 : copy = (struct inflate_state FAR *)
1477 0 : ZALLOC(source, 1, sizeof(struct inflate_state));
1478 0 : if (copy == Z_NULL) return Z_MEM_ERROR;
1479 0 : window = Z_NULL;
1480 0 : if (state->window != Z_NULL) {
1481 0 : window = (unsigned char FAR *)
1482 0 : ZALLOC(source, 1U << state->wbits, sizeof(unsigned char));
1483 0 : if (window == Z_NULL) {
1484 0 : ZFREE(source, copy);
1485 0 : return Z_MEM_ERROR;
1486 : }
1487 : }
1488 :
1489 : /* copy state */
1490 0 : zmemcpy((voidpf)dest, (voidpf)source, sizeof(z_stream));
1491 0 : zmemcpy((voidpf)copy, (voidpf)state, sizeof(struct inflate_state));
1492 0 : copy->strm = dest;
1493 0 : if (state->lencode >= state->codes &&
1494 0 : state->lencode <= state->codes + ENOUGH - 1) {
1495 0 : copy->lencode = copy->codes + (state->lencode - state->codes);
1496 0 : copy->distcode = copy->codes + (state->distcode - state->codes);
1497 : }
1498 0 : copy->next = copy->codes + (state->next - state->codes);
1499 0 : if (window != Z_NULL) {
1500 0 : wsize = 1U << state->wbits;
1501 0 : zmemcpy(window, state->window, wsize);
1502 : }
1503 0 : copy->window = window;
1504 0 : dest->state = (struct internal_state FAR *)copy;
1505 0 : return Z_OK;
1506 : }
1507 :
1508 0 : int ZEXPORT inflateUndermine(strm, subvert)
1509 : z_streamp strm;
1510 : int subvert;
1511 : {
1512 : struct inflate_state FAR *state;
1513 :
1514 0 : if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
1515 0 : state = (struct inflate_state FAR *)strm->state;
1516 : #ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR
1517 : state->sane = !subvert;
1518 : return Z_OK;
1519 : #else
1520 : (void)subvert;
1521 0 : state->sane = 1;
1522 0 : return Z_DATA_ERROR;
1523 : #endif
1524 : }
1525 :
1526 0 : int ZEXPORT inflateValidate(strm, check)
1527 : z_streamp strm;
1528 : int check;
1529 : {
1530 : struct inflate_state FAR *state;
1531 :
1532 0 : if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
1533 0 : state = (struct inflate_state FAR *)strm->state;
1534 0 : if (check)
1535 0 : state->wrap |= 4;
1536 : else
1537 0 : state->wrap &= ~4;
1538 0 : return Z_OK;
1539 : }
1540 :
1541 0 : long ZEXPORT inflateMark(strm)
1542 : z_streamp strm;
1543 : {
1544 : struct inflate_state FAR *state;
1545 :
1546 0 : if (inflateStateCheck(strm))
1547 0 : return -(1L << 16);
1548 0 : state = (struct inflate_state FAR *)strm->state;
1549 0 : return (long)(((unsigned long)((long)state->back)) << 16) +
1550 0 : (state->mode == COPY ? state->length :
1551 0 : (state->mode == MATCH ? state->was - state->length : 0));
1552 : }
1553 :
1554 0 : unsigned long ZEXPORT inflateCodesUsed(strm)
1555 : z_streamp strm;
1556 : {
1557 : struct inflate_state FAR *state;
1558 0 : if (inflateStateCheck(strm)) return (unsigned long)-1;
1559 0 : state = (struct inflate_state FAR *)strm->state;
1560 0 : return (unsigned long)(state->next - state->codes);
1561 : }
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