Coverage Report

Created: 2025-12-08 09:28

next uncovered line (L), next uncovered region (R), next uncovered branch (B)
/work/workdir/UnpackedTarball/zlib/inflate.c
Line
Count
Source
1
/* inflate.c -- zlib decompression
2
 * Copyright (C) 1995-2022 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
263M
local int inflateStateCheck(z_streamp strm) {
95
263M
    struct inflate_state FAR *state;
96
263M
    if (strm == Z_NULL ||
97
263M
        strm->zalloc == (alloc_func)0 || strm->zfree == (free_func)0)
98
0
        return 1;
99
263M
    state = (struct inflate_state FAR *)strm->state;
100
263M
    if (state == Z_NULL || state->strm != strm ||
101
263M
        state->mode < HEAD || state->mode > SYNC)
102
4.99k
        return 1;
103
263M
    return 0;
104
263M
}
105
106
291k
int ZEXPORT inflateResetKeep(z_streamp strm) {
107
291k
    struct inflate_state FAR *state;
108
109
291k
    if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
110
291k
    state = (struct inflate_state FAR *)strm->state;
111
291k
    strm->total_in = strm->total_out = state->total = 0;
112
291k
    strm->msg = Z_NULL;
113
291k
    if (state->wrap)        /* to support ill-conceived Java test suite */
114
70.1k
        strm->adler = state->wrap & 1;
115
291k
    state->mode = HEAD;
116
291k
    state->last = 0;
117
291k
    state->havedict = 0;
118
291k
    state->flags = -1;
119
291k
    state->dmax = 32768U;
120
291k
    state->head = Z_NULL;
121
291k
    state->hold = 0;
122
291k
    state->bits = 0;
123
291k
    state->lencode = state->distcode = state->next = state->codes;
124
291k
    state->sane = 1;
125
291k
    state->back = -1;
126
291k
    Tracev((stderr, "inflate: reset\n"));
127
291k
    return Z_OK;
128
291k
}
129
130
291k
int ZEXPORT inflateReset(z_streamp strm) {
131
291k
    struct inflate_state FAR *state;
132
133
291k
    if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
134
291k
    state = (struct inflate_state FAR *)strm->state;
135
291k
    state->wsize = 0;
136
291k
    state->whave = 0;
137
291k
    state->wnext = 0;
138
291k
    return inflateResetKeep(strm);
139
291k
}
140
141
287k
int ZEXPORT inflateReset2(z_streamp strm, int windowBits) {
142
287k
    int wrap;
143
287k
    struct inflate_state FAR *state;
144
145
    /* get the state */
146
287k
    if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
147
287k
    state = (struct inflate_state FAR *)strm->state;
148
149
    /* extract wrap request from windowBits parameter */
150
287k
    if (windowBits < 0) {
151
220k
        if (windowBits < -15)
152
0
            return Z_STREAM_ERROR;
153
220k
        wrap = 0;
154
220k
        windowBits = -windowBits;
155
220k
    }
156
66.9k
    else {
157
66.9k
        wrap = (windowBits >> 4) + 5;
158
66.9k
#ifdef GUNZIP
159
66.9k
        if (windowBits < 48)
160
66.9k
            windowBits &= 15;
161
66.9k
#endif
162
66.9k
    }
163
164
    /* set number of window bits, free window if different */
165
287k
    if (windowBits && (windowBits < 8 || windowBits > 15))
166
0
        return Z_STREAM_ERROR;
167
287k
    if (state->window != Z_NULL && state->wbits != (unsigned)windowBits) {
168
0
        ZFREE(strm, state->window);
169
0
        state->window = Z_NULL;
170
0
    }
171
172
    /* update state and reset the rest of it */
173
287k
    state->wrap = wrap;
174
287k
    state->wbits = (unsigned)windowBits;
175
287k
    return inflateReset(strm);
176
287k
}
177
178
int ZEXPORT inflateInit2_(z_streamp strm, int windowBits,
179
268k
                          const char *version, int stream_size) {
180
268k
    int ret;
181
268k
    struct inflate_state FAR *state;
182
183
268k
    if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
184
268k
        stream_size != (int)(sizeof(z_stream)))
185
0
        return Z_VERSION_ERROR;
186
268k
    if (strm == Z_NULL) return Z_STREAM_ERROR;
187
268k
    strm->msg = Z_NULL;                 /* in case we return an error */
188
268k
    if (strm->zalloc == (alloc_func)0) {
189
#ifdef Z_SOLO
190
        return Z_STREAM_ERROR;
191
#else
192
257k
        strm->zalloc = zcalloc;
193
257k
        strm->opaque = (voidpf)0;
194
257k
#endif
195
257k
    }
196
268k
    if (strm->zfree == (free_func)0)
197
#ifdef Z_SOLO
198
        return Z_STREAM_ERROR;
199
#else
200
257k
        strm->zfree = zcfree;
201
268k
#endif
202
268k
    state = (struct inflate_state FAR *)
203
268k
            ZALLOC(strm, 1, sizeof(struct inflate_state));
204
268k
    if (state == Z_NULL) return Z_MEM_ERROR;
205
268k
    Tracev((stderr, "inflate: allocated\n"));
206
268k
    strm->state = (struct internal_state FAR *)state;
207
268k
    state->strm = strm;
208
268k
    state->window = Z_NULL;
209
268k
    state->mode = HEAD;     /* to pass state test in inflateReset2() */
210
268k
    ret = inflateReset2(strm, windowBits);
211
268k
    if (ret != Z_OK) {
212
0
        ZFREE(strm, state);
213
0
        strm->state = Z_NULL;
214
0
    }
215
268k
    return ret;
216
268k
}
217
218
int ZEXPORT inflateInit_(z_streamp strm, const char *version,
219
37.2k
                         int stream_size) {
220
37.2k
    return inflateInit2_(strm, DEF_WBITS, version, stream_size);
221
37.2k
}
222
223
0
int ZEXPORT inflatePrime(z_streamp strm, int bits, int value) {
224
0
    struct inflate_state FAR *state;
225
226
0
    if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
227
0
    if (bits == 0)
228
0
        return Z_OK;
229
0
    state = (struct inflate_state FAR *)strm->state;
230
0
    if (bits < 0) {
231
0
        state->hold = 0;
232
0
        state->bits = 0;
233
0
        return Z_OK;
234
0
    }
235
0
    if (bits > 16 || state->bits + (uInt)bits > 32) return Z_STREAM_ERROR;
236
0
    value &= (1L << bits) - 1;
237
0
    state->hold += (unsigned)value << state->bits;
238
0
    state->bits += (uInt)bits;
239
0
    return Z_OK;
240
0
}
241
242
/*
243
   Return state with length and distance decoding tables and index sizes set to
244
   fixed code decoding.  Normally this returns fixed tables from inffixed.h.
245
   If BUILDFIXED is defined, then instead this routine builds the tables the
246
   first time it's called, and returns those tables the first time and
247
   thereafter.  This reduces the size of the code by about 2K bytes, in
248
   exchange for a little execution time.  However, BUILDFIXED should not be
249
   used for threaded applications, since the rewriting of the tables and virgin
250
   may not be thread-safe.
251
 */
252
139k
local void fixedtables(struct inflate_state FAR *state) {
253
#ifdef BUILDFIXED
254
    static int virgin = 1;
255
    static code *lenfix, *distfix;
256
    static code fixed[544];
257
258
    /* build fixed huffman tables if first call (may not be thread safe) */
259
    if (virgin) {
260
        unsigned sym, bits;
261
        static code *next;
262
263
        /* literal/length table */
264
        sym = 0;
265
        while (sym < 144) state->lens[sym++] = 8;
266
        while (sym < 256) state->lens[sym++] = 9;
267
        while (sym < 280) state->lens[sym++] = 7;
268
        while (sym < 288) state->lens[sym++] = 8;
269
        next = fixed;
270
        lenfix = next;
271
        bits = 9;
272
        inflate_table(LENS, state->lens, 288, &(next), &(bits), state->work);
273
274
        /* distance table */
275
        sym = 0;
276
        while (sym < 32) state->lens[sym++] = 5;
277
        distfix = next;
278
        bits = 5;
279
        inflate_table(DISTS, state->lens, 32, &(next), &(bits), state->work);
280
281
        /* do this just once */
282
        virgin = 0;
283
    }
284
#else /* !BUILDFIXED */
285
139k
#   include "inffixed.h"
286
139k
#endif /* BUILDFIXED */
287
139k
    state->lencode = lenfix;
288
139k
    state->lenbits = 9;
289
139k
    state->distcode = distfix;
290
139k
    state->distbits = 5;
291
139k
}
292
293
#ifdef MAKEFIXED
294
#include <stdio.h>
295
296
/*
297
   Write out the inffixed.h that is #include'd above.  Defining MAKEFIXED also
298
   defines BUILDFIXED, so the tables are built on the fly.  makefixed() writes
299
   those tables to stdout, which would be piped to inffixed.h.  A small program
300
   can simply call makefixed to do this:
301
302
    void makefixed(void);
303
304
    int main(void)
305
    {
306
        makefixed();
307
        return 0;
308
    }
309
310
   Then that can be linked with zlib built with MAKEFIXED defined and run:
311
312
    a.out > inffixed.h
313
 */
314
void makefixed(void)
315
{
316
    unsigned low, size;
317
    struct inflate_state state;
318
319
    fixedtables(&state);
320
    puts("    /* inffixed.h -- table for decoding fixed codes");
321
    puts("     * Generated automatically by makefixed().");
322
    puts("     */");
323
    puts("");
324
    puts("    /* WARNING: this file should *not* be used by applications.");
325
    puts("       It is part of the implementation of this library and is");
326
    puts("       subject to change. Applications should only use zlib.h.");
327
    puts("     */");
328
    puts("");
329
    size = 1U << 9;
330
    printf("    static const code lenfix[%u] = {", size);
331
    low = 0;
332
    for (;;) {
333
        if ((low % 7) == 0) printf("\n        ");
334
        printf("{%u,%u,%d}", (low & 127) == 99 ? 64 : state.lencode[low].op,
335
               state.lencode[low].bits, state.lencode[low].val);
336
        if (++low == size) break;
337
        putchar(',');
338
    }
339
    puts("\n    };");
340
    size = 1U << 5;
341
    printf("\n    static const code distfix[%u] = {", size);
342
    low = 0;
343
    for (;;) {
344
        if ((low % 6) == 0) printf("\n        ");
345
        printf("{%u,%u,%d}", state.distcode[low].op, state.distcode[low].bits,
346
               state.distcode[low].val);
347
        if (++low == size) break;
348
        putchar(',');
349
    }
350
    puts("\n    };");
351
}
352
#endif /* MAKEFIXED */
353
354
/*
355
   Update the window with the last wsize (normally 32K) bytes written before
356
   returning.  If window does not exist yet, create it.  This is only called
357
   when a window is already in use, or when output has been written during this
358
   inflate call, but the end of the deflate stream has not been reached yet.
359
   It is also called to create a window for dictionary data when a dictionary
360
   is loaded.
361
362
   Providing output buffers larger than 32K to inflate() should provide a speed
363
   advantage, since only the last 32K of output is copied to the sliding window
364
   upon return from inflate(), and since all distances after the first 32K of
365
   output will fall in the output data, making match copies simpler and faster.
366
   The advantage may be dependent on the size of the processor's data caches.
367
 */
368
262M
local int updatewindow(z_streamp strm, const Bytef *end, unsigned copy) {
369
262M
    struct inflate_state FAR *state;
370
262M
    unsigned dist;
371
372
262M
    state = (struct inflate_state FAR *)strm->state;
373
374
    /* if it hasn't been done already, allocate space for the window */
375
262M
    if (state->window == Z_NULL) {
376
227k
        state->window = (unsigned char FAR *)
377
227k
                        ZALLOC(strm, 1U << state->wbits,
378
227k
                               sizeof(unsigned char));
379
227k
        if (state->window == Z_NULL) return 1;
380
227k
    }
381
382
    /* if window not in use yet, initialize */
383
262M
    if (state->wsize == 0) {
384
236k
        state->wsize = 1U << state->wbits;
385
236k
        state->wnext = 0;
386
236k
        state->whave = 0;
387
236k
    }
388
389
    /* copy state->wsize or less output bytes into the circular window */
390
262M
    if (copy >= state->wsize) {
391
32.3k
        zmemcpy(state->window, end - state->wsize, state->wsize);
392
32.3k
        state->wnext = 0;
393
32.3k
        state->whave = state->wsize;
394
32.3k
    }
395
262M
    else {
396
262M
        dist = state->wsize - state->wnext;
397
262M
        if (dist > copy) dist = copy;
398
262M
        zmemcpy(state->window + state->wnext, end - copy, dist);
399
262M
        copy -= dist;
400
262M
        if (copy) {
401
38.4k
            zmemcpy(state->window, end - copy, copy);
402
38.4k
            state->wnext = copy;
403
38.4k
            state->whave = state->wsize;
404
38.4k
        }
405
262M
        else {
406
262M
            state->wnext += dist;
407
262M
            if (state->wnext == state->wsize) state->wnext = 0;
408
262M
            if (state->whave < state->wsize) state->whave += dist;
409
262M
        }
410
262M
    }
411
262M
    return 0;
412
262M
}
413
414
/* Macros for inflate(): */
415
416
/* check function to use adler32() for zlib or crc32() for gzip */
417
#ifdef GUNZIP
418
#  define UPDATE_CHECK(check, buf, len) \
419
5.60M
    (state->flags ? crc32(check, buf, len) : adler32(check, buf, len))
420
#else
421
#  define UPDATE_CHECK(check, buf, len) adler32(check, buf, len)
422
#endif
423
424
/* check macros for header crc */
425
#ifdef GUNZIP
426
#  define CRC2(check, word) \
427
0
    do { \
428
0
        hbuf[0] = (unsigned char)(word); \
429
0
        hbuf[1] = (unsigned char)((word) >> 8); \
430
0
        check = crc32(check, hbuf, 2); \
431
0
    } while (0)
432
433
#  define CRC4(check, word) \
434
0
    do { \
435
0
        hbuf[0] = (unsigned char)(word); \
436
0
        hbuf[1] = (unsigned char)((word) >> 8); \
437
0
        hbuf[2] = (unsigned char)((word) >> 16); \
438
0
        hbuf[3] = (unsigned char)((word) >> 24); \
439
0
        check = crc32(check, hbuf, 4); \
440
0
    } while (0)
441
#endif
442
443
/* Load registers with state in inflate() for speed */
444
#define LOAD() \
445
263M
    do { \
446
263M
        put = strm->next_out; \
447
263M
        left = strm->avail_out; \
448
263M
        next = strm->next_in; \
449
263M
        have = strm->avail_in; \
450
263M
        hold = state->hold; \
451
263M
        bits = state->bits; \
452
263M
    } while (0)
453
454
/* Restore state from registers in inflate() */
455
#define RESTORE() \
456
263M
    do { \
457
263M
        strm->next_out = put; \
458
263M
        strm->avail_out = left; \
459
263M
        strm->next_in = next; \
460
263M
        strm->avail_in = have; \
461
263M
        state->hold = hold; \
462
263M
        state->bits = bits; \
463
263M
    } while (0)
464
465
/* Clear the input bit accumulator */
466
#define INITBITS() \
467
177k
    do { \
468
177k
        hold = 0; \
469
177k
        bits = 0; \
470
177k
    } while (0)
471
472
/* Get a byte of input into the bit accumulator, or return from inflate()
473
   if there is no input available. */
474
#define PULLBYTE() \
475
40.6M
    do { \
476
40.6M
        if (have == 0) goto inf_leave; \
477
40.6M
        have--; \
478
40.3M
        hold += (unsigned long)(*next++) << bits; \
479
40.3M
        bits += 8; \
480
40.3M
    } while (0)
481
482
/* Assure that there are at least n bits in the bit accumulator.  If there is
483
   not enough available input to do that, then return from inflate(). */
484
#define NEEDBITS(n) \
485
17.0M
    do { \
486
26.5M
        while (bits < (unsigned)(n)) \
487
17.0M
            PULLBYTE(); \
488
17.0M
    } while (0)
489
490
/* Return the low n bits of the bit accumulator (n < 16) */
491
#define BITS(n) \
492
106M
    ((unsigned)hold & ((1U << (n)) - 1))
493
494
/* Remove n bits from the bit accumulator */
495
#define DROPBITS(n) \
496
75.4M
    do { \
497
75.4M
        hold >>= (n); \
498
75.4M
        bits -= (unsigned)(n); \
499
75.4M
    } while (0)
500
501
/* Remove zero to seven bits as needed to go to a byte boundary */
502
#define BYTEBITS() \
503
297k
    do { \
504
297k
        hold >>= bits & 7; \
505
297k
        bits -= bits & 7; \
506
297k
    } while (0)
507
508
/*
509
   inflate() uses a state machine to process as much input data and generate as
510
   much output data as possible before returning.  The state machine is
511
   structured roughly as follows:
512
513
    for (;;) switch (state) {
514
    ...
515
    case STATEn:
516
        if (not enough input data or output space to make progress)
517
            return;
518
        ... make progress ...
519
        state = STATEm;
520
        break;
521
    ...
522
    }
523
524
   so when inflate() is called again, the same case is attempted again, and
525
   if the appropriate resources are provided, the machine proceeds to the
526
   next state.  The NEEDBITS() macro is usually the way the state evaluates
527
   whether it can proceed or should return.  NEEDBITS() does the return if
528
   the requested bits are not available.  The typical use of the BITS macros
529
   is:
530
531
        NEEDBITS(n);
532
        ... do something with BITS(n) ...
533
        DROPBITS(n);
534
535
   where NEEDBITS(n) either returns from inflate() if there isn't enough
536
   input left to load n bits into the accumulator, or it continues.  BITS(n)
537
   gives the low n bits in the accumulator.  When done, DROPBITS(n) drops
538
   the low n bits off the accumulator.  INITBITS() clears the accumulator
539
   and sets the number of available bits to zero.  BYTEBITS() discards just
540
   enough bits to put the accumulator on a byte boundary.  After BYTEBITS()
541
   and a NEEDBITS(8), then BITS(8) would return the next byte in the stream.
542
543
   NEEDBITS(n) uses PULLBYTE() to get an available byte of input, or to return
544
   if there is no input available.  The decoding of variable length codes uses
545
   PULLBYTE() directly in order to pull just enough bytes to decode the next
546
   code, and no more.
547
548
   Some states loop until they get enough input, making sure that enough
549
   state information is maintained to continue the loop where it left off
550
   if NEEDBITS() returns in the loop.  For example, want, need, and keep
551
   would all have to actually be part of the saved state in case NEEDBITS()
552
   returns:
553
554
    case STATEw:
555
        while (want < need) {
556
            NEEDBITS(n);
557
            keep[want++] = BITS(n);
558
            DROPBITS(n);
559
        }
560
        state = STATEx;
561
    case STATEx:
562
563
   As shown above, if the next state is also the next case, then the break
564
   is omitted.
565
566
   A state may also return if there is not enough output space available to
567
   complete that state.  Those states are copying stored data, writing a
568
   literal byte, and copying a matching string.
569
570
   When returning, a "goto inf_leave" is used to update the total counters,
571
   update the check value, and determine whether any progress has been made
572
   during that inflate() call in order to return the proper return code.
573
   Progress is defined as a change in either strm->avail_in or strm->avail_out.
574
   When there is a window, goto inf_leave will update the window with the last
575
   output written.  If a goto inf_leave occurs in the middle of decompression
576
   and there is no window currently, goto inf_leave will create one and copy
577
   output to the window for the next call of inflate().
578
579
   In this implementation, the flush parameter of inflate() only affects the
580
   return code (per zlib.h).  inflate() always writes as much as possible to
581
   strm->next_out, given the space available and the provided input--the effect
582
   documented in zlib.h of Z_SYNC_FLUSH.  Furthermore, inflate() always defers
583
   the allocation of and copying into a sliding window until necessary, which
584
   provides the effect documented in zlib.h for Z_FINISH when the entire input
585
   stream available.  So the only thing the flush parameter actually does is:
586
   when flush is set to Z_FINISH, inflate() cannot return Z_OK.  Instead it
587
   will return Z_BUF_ERROR if it has not reached the end of the stream.
588
 */
589
590
262M
int ZEXPORT inflate(z_streamp strm, int flush) {
591
262M
    struct inflate_state FAR *state;
592
262M
    z_const unsigned char FAR *next;    /* next input */
593
262M
    unsigned char FAR *put;     /* next output */
594
262M
    unsigned have, left;        /* available input and output */
595
262M
    unsigned long hold;         /* bit buffer */
596
262M
    unsigned bits;              /* bits in bit buffer */
597
262M
    unsigned in, out;           /* save starting available input and output */
598
262M
    unsigned copy;              /* number of stored or match bytes to copy */
599
262M
    unsigned char FAR *from;    /* where to copy match bytes from */
600
262M
    code here;                  /* current decoding table entry */
601
262M
    code last;                  /* parent table entry */
602
262M
    unsigned len;               /* length to copy for repeats, bits to drop */
603
262M
    int ret;                    /* return code */
604
262M
#ifdef GUNZIP
605
262M
    unsigned char hbuf[4];      /* buffer for gzip header crc calculation */
606
262M
#endif
607
262M
    static const unsigned short order[19] = /* permutation of code lengths */
608
262M
        {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
609
610
262M
    if (inflateStateCheck(strm) || strm->next_out == Z_NULL ||
611
262M
        (strm->next_in == Z_NULL && strm->avail_in != 0))
612
0
        return Z_STREAM_ERROR;
613
614
262M
    state = (struct inflate_state FAR *)strm->state;
615
262M
    if (state->mode == TYPE) state->mode = TYPEDO;      /* skip check */
616
262M
    LOAD();
617
262M
    in = have;
618
262M
    out = left;
619
262M
    ret = Z_OK;
620
262M
    for (;;)
621
565M
        switch (state->mode) {
622
290k
        case HEAD:
623
290k
            if (state->wrap == 0) {
624
220k
                state->mode = TYPEDO;
625
220k
                break;
626
220k
            }
627
70.0k
            NEEDBITS(16);
628
68.4k
#ifdef GUNZIP
629
68.4k
            if ((state->wrap & 2) && hold == 0x8b1f) {  /* gzip header */
630
0
                if (state->wbits == 0)
631
0
                    state->wbits = 15;
632
0
                state->check = crc32(0L, Z_NULL, 0);
633
0
                CRC2(state->check, hold);
634
0
                INITBITS();
635
0
                state->mode = FLAGS;
636
0
                break;
637
0
            }
638
68.4k
            if (state->head != Z_NULL)
639
0
                state->head->done = -1;
640
68.4k
            if (!(state->wrap & 1) ||   /* check if zlib header allowed */
641
#else
642
            if (
643
#endif
644
68.4k
                ((BITS(8) << 8) + (hold >> 8)) % 31) {
645
1.31k
                strm->msg = (char *)"incorrect header check";
646
1.31k
                state->mode = BAD;
647
1.31k
                break;
648
1.31k
            }
649
67.1k
            if (BITS(4) != Z_DEFLATED) {
650
449
                strm->msg = (char *)"unknown compression method";
651
449
                state->mode = BAD;
652
449
                break;
653
449
            }
654
66.7k
            DROPBITS(4);
655
66.7k
            len = BITS(4) + 8;
656
66.7k
            if (state->wbits == 0)
657
0
                state->wbits = len;
658
66.7k
            if (len > 15 || len > state->wbits) {
659
93
                strm->msg = (char *)"invalid window size";
660
93
                state->mode = BAD;
661
93
                break;
662
93
            }
663
66.6k
            state->dmax = 1U << len;
664
66.6k
            state->flags = 0;               /* indicate zlib header */
665
66.6k
            Tracev((stderr, "inflate:   zlib header ok\n"));
666
66.6k
            strm->adler = state->check = adler32(0L, Z_NULL, 0);
667
66.6k
            state->mode = hold & 0x200 ? DICTID : TYPE;
668
66.6k
            INITBITS();
669
66.6k
            break;
670
0
#ifdef GUNZIP
671
0
        case FLAGS:
672
0
            NEEDBITS(16);
673
0
            state->flags = (int)(hold);
674
0
            if ((state->flags & 0xff) != Z_DEFLATED) {
675
0
                strm->msg = (char *)"unknown compression method";
676
0
                state->mode = BAD;
677
0
                break;
678
0
            }
679
0
            if (state->flags & 0xe000) {
680
0
                strm->msg = (char *)"unknown header flags set";
681
0
                state->mode = BAD;
682
0
                break;
683
0
            }
684
0
            if (state->head != Z_NULL)
685
0
                state->head->text = (int)((hold >> 8) & 1);
686
0
            if ((state->flags & 0x0200) && (state->wrap & 4))
687
0
                CRC2(state->check, hold);
688
0
            INITBITS();
689
0
            state->mode = TIME;
690
                /* fallthrough */
691
0
        case TIME:
692
0
            NEEDBITS(32);
693
0
            if (state->head != Z_NULL)
694
0
                state->head->time = hold;
695
0
            if ((state->flags & 0x0200) && (state->wrap & 4))
696
0
                CRC4(state->check, hold);
697
0
            INITBITS();
698
0
            state->mode = OS;
699
                /* fallthrough */
700
0
        case OS:
701
0
            NEEDBITS(16);
702
0
            if (state->head != Z_NULL) {
703
0
                state->head->xflags = (int)(hold & 0xff);
704
0
                state->head->os = (int)(hold >> 8);
705
0
            }
706
0
            if ((state->flags & 0x0200) && (state->wrap & 4))
707
0
                CRC2(state->check, hold);
708
0
            INITBITS();
709
0
            state->mode = EXLEN;
710
                /* fallthrough */
711
0
        case EXLEN:
712
0
            if (state->flags & 0x0400) {
713
0
                NEEDBITS(16);
714
0
                state->length = (unsigned)(hold);
715
0
                if (state->head != Z_NULL)
716
0
                    state->head->extra_len = (unsigned)hold;
717
0
                if ((state->flags & 0x0200) && (state->wrap & 4))
718
0
                    CRC2(state->check, hold);
719
0
                INITBITS();
720
0
            }
721
0
            else if (state->head != Z_NULL)
722
0
                state->head->extra = Z_NULL;
723
0
            state->mode = EXTRA;
724
                /* fallthrough */
725
0
        case EXTRA:
726
0
            if (state->flags & 0x0400) {
727
0
                copy = state->length;
728
0
                if (copy > have) copy = have;
729
0
                if (copy) {
730
0
                    if (state->head != Z_NULL &&
731
0
                        state->head->extra != Z_NULL &&
732
0
                        (len = state->head->extra_len - state->length) <
733
0
                            state->head->extra_max) {
734
0
                        zmemcpy(state->head->extra + len, next,
735
0
                                len + copy > state->head->extra_max ?
736
0
                                state->head->extra_max - len : copy);
737
0
                    }
738
0
                    if ((state->flags & 0x0200) && (state->wrap & 4))
739
0
                        state->check = crc32(state->check, next, copy);
740
0
                    have -= copy;
741
0
                    next += copy;
742
0
                    state->length -= copy;
743
0
                }
744
0
                if (state->length) goto inf_leave;
745
0
            }
746
0
            state->length = 0;
747
0
            state->mode = NAME;
748
                /* fallthrough */
749
0
        case NAME:
750
0
            if (state->flags & 0x0800) {
751
0
                if (have == 0) goto inf_leave;
752
0
                copy = 0;
753
0
                do {
754
0
                    len = (unsigned)(next[copy++]);
755
0
                    if (state->head != Z_NULL &&
756
0
                            state->head->name != Z_NULL &&
757
0
                            state->length < state->head->name_max)
758
0
                        state->head->name[state->length++] = (Bytef)len;
759
0
                } while (len && copy < have);
760
0
                if ((state->flags & 0x0200) && (state->wrap & 4))
761
0
                    state->check = crc32(state->check, next, copy);
762
0
                have -= copy;
763
0
                next += copy;
764
0
                if (len) goto inf_leave;
765
0
            }
766
0
            else if (state->head != Z_NULL)
767
0
                state->head->name = Z_NULL;
768
0
            state->length = 0;
769
0
            state->mode = COMMENT;
770
                /* fallthrough */
771
0
        case COMMENT:
772
0
            if (state->flags & 0x1000) {
773
0
                if (have == 0) goto inf_leave;
774
0
                copy = 0;
775
0
                do {
776
0
                    len = (unsigned)(next[copy++]);
777
0
                    if (state->head != Z_NULL &&
778
0
                            state->head->comment != Z_NULL &&
779
0
                            state->length < state->head->comm_max)
780
0
                        state->head->comment[state->length++] = (Bytef)len;
781
0
                } while (len && copy < have);
782
0
                if ((state->flags & 0x0200) && (state->wrap & 4))
783
0
                    state->check = crc32(state->check, next, copy);
784
0
                have -= copy;
785
0
                next += copy;
786
0
                if (len) goto inf_leave;
787
0
            }
788
0
            else if (state->head != Z_NULL)
789
0
                state->head->comment = Z_NULL;
790
0
            state->mode = HCRC;
791
                /* fallthrough */
792
0
        case HCRC:
793
0
            if (state->flags & 0x0200) {
794
0
                NEEDBITS(16);
795
0
                if ((state->wrap & 4) && hold != (state->check & 0xffff)) {
796
0
                    strm->msg = (char *)"header crc mismatch";
797
0
                    state->mode = BAD;
798
0
                    break;
799
0
                }
800
0
                INITBITS();
801
0
            }
802
0
            if (state->head != Z_NULL) {
803
0
                state->head->hcrc = (int)((state->flags >> 9) & 1);
804
0
                state->head->done = 1;
805
0
            }
806
0
            strm->adler = state->check = crc32(0L, Z_NULL, 0);
807
0
            state->mode = TYPE;
808
0
            break;
809
0
#endif
810
244
        case DICTID:
811
244
            NEEDBITS(32);
812
109
            strm->adler = state->check = ZSWAP32(hold);
813
109
            INITBITS();
814
109
            state->mode = DICT;
815
                /* fallthrough */
816
109
        case DICT:
817
109
            if (state->havedict == 0) {
818
109
                RESTORE();
819
109
                return Z_NEED_DICT;
820
109
            }
821
0
            strm->adler = state->check = adler32(0L, Z_NULL, 0);
822
0
            state->mode = TYPE;
823
                /* fallthrough */
824
475k
        case TYPE:
825
475k
            if (flush == Z_BLOCK || flush == Z_TREES) goto inf_leave;
826
                /* fallthrough */
827
907k
        case TYPEDO:
828
907k
            if (state->last) {
829
191k
                BYTEBITS();
830
191k
                state->mode = CHECK;
831
191k
                break;
832
191k
            }
833
716k
            NEEDBITS(3);
834
503k
            state->last = BITS(1);
835
503k
            DROPBITS(1);
836
503k
            switch (BITS(2)) {
837
105k
            case 0:                             /* stored block */
838
105k
                Tracev((stderr, "inflate:     stored block%s\n",
839
105k
                        state->last ? " (last)" : ""));
840
105k
                state->mode = STORED;
841
105k
                break;
842
139k
            case 1:                             /* fixed block */
843
139k
                fixedtables(state);
844
139k
                Tracev((stderr, "inflate:     fixed codes block%s\n",
845
139k
                        state->last ? " (last)" : ""));
846
139k
                state->mode = LEN_;             /* decode codes */
847
139k
                if (flush == Z_TREES) {
848
0
                    DROPBITS(2);
849
0
                    goto inf_leave;
850
0
                }
851
139k
                break;
852
258k
            case 2:                             /* dynamic block */
853
258k
                Tracev((stderr, "inflate:     dynamic codes block%s\n",
854
258k
                        state->last ? " (last)" : ""));
855
258k
                state->mode = TABLE;
856
258k
                break;
857
396
            case 3:
858
396
                strm->msg = (char *)"invalid block type";
859
396
                state->mode = BAD;
860
503k
            }
861
503k
            DROPBITS(2);
862
503k
            break;
863
106k
        case STORED:
864
106k
            BYTEBITS();                         /* go to byte boundary */
865
106k
            NEEDBITS(32);
866
104k
            if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) {
867
2.30k
                strm->msg = (char *)"invalid stored block lengths";
868
2.30k
                state->mode = BAD;
869
2.30k
                break;
870
2.30k
            }
871
102k
            state->length = (unsigned)hold & 0xffff;
872
102k
            Tracev((stderr, "inflate:       stored length %u\n",
873
102k
                    state->length));
874
102k
            INITBITS();
875
102k
            state->mode = COPY_;
876
102k
            if (flush == Z_TREES) goto inf_leave;
877
                /* fallthrough */
878
102k
        case COPY_:
879
102k
            state->mode = COPY;
880
                /* fallthrough */
881
187k
        case COPY:
882
187k
            copy = state->length;
883
187k
            if (copy) {
884
87.1k
                if (copy > have) copy = have;
885
87.1k
                if (copy > left) copy = left;
886
87.1k
                if (copy == 0) goto inf_leave;
887
43.3k
                zmemcpy(put, next, copy);
888
43.3k
                have -= copy;
889
43.3k
                next += copy;
890
43.3k
                left -= copy;
891
43.3k
                put += copy;
892
43.3k
                state->length -= copy;
893
43.3k
                break;
894
87.1k
            }
895
100k
            Tracev((stderr, "inflate:       stored end\n"));
896
100k
            state->mode = TYPE;
897
100k
            break;
898
258k
        case TABLE:
899
258k
            NEEDBITS(14);
900
258k
            state->nlen = BITS(5) + 257;
901
258k
            DROPBITS(5);
902
258k
            state->ndist = BITS(5) + 1;
903
258k
            DROPBITS(5);
904
258k
            state->ncode = BITS(4) + 4;
905
258k
            DROPBITS(4);
906
258k
#ifndef PKZIP_BUG_WORKAROUND
907
258k
            if (state->nlen > 286 || state->ndist > 30) {
908
720
                strm->msg = (char *)"too many length or distance symbols";
909
720
                state->mode = BAD;
910
720
                break;
911
720
            }
912
257k
#endif
913
257k
            Tracev((stderr, "inflate:       table sizes ok\n"));
914
257k
            state->have = 0;
915
257k
            state->mode = LENLENS;
916
                /* fallthrough */
917
258k
        case LENLENS:
918
4.17M
            while (state->have < state->ncode) {
919
3.91M
                NEEDBITS(3);
920
3.91M
                state->lens[order[state->have++]] = (unsigned short)BITS(3);
921
3.91M
                DROPBITS(3);
922
3.91M
            }
923
1.21M
            while (state->have < 19)
924
955k
                state->lens[order[state->have++]] = 0;
925
256k
            state->next = state->codes;
926
256k
            state->lencode = (const code FAR *)(state->next);
927
256k
            state->lenbits = 7;
928
256k
            ret = inflate_table(CODES, state->lens, 19, &(state->next),
929
256k
                                &(state->lenbits), state->work);
930
256k
            if (ret) {
931
6.47k
                strm->msg = (char *)"invalid code lengths set";
932
6.47k
                state->mode = BAD;
933
6.47k
                break;
934
6.47k
            }
935
249k
            Tracev((stderr, "inflate:       code lengths ok\n"));
936
249k
            state->have = 0;
937
249k
            state->mode = CODELENS;
938
                /* fallthrough */
939
253k
        case CODELENS:
940
28.5M
            while (state->have < state->nlen + state->ndist) {
941
38.9M
                for (;;) {
942
38.9M
                    here = state->lencode[BITS(state->lenbits)];
943
38.9M
                    if ((unsigned)(here.bits) <= bits) break;
944
10.6M
                    PULLBYTE();
945
10.6M
                }
946
28.2M
                if (here.val < 16) {
947
25.6M
                    DROPBITS(here.bits);
948
25.6M
                    state->lens[state->have++] = here.val;
949
25.6M
                }
950
2.62M
                else {
951
2.62M
                    if (here.val == 16) {
952
454k
                        NEEDBITS(here.bits + 2);
953
453k
                        DROPBITS(here.bits);
954
453k
                        if (state->have == 0) {
955
173
                            strm->msg = (char *)"invalid bit length repeat";
956
173
                            state->mode = BAD;
957
173
                            break;
958
173
                        }
959
453k
                        len = state->lens[state->have - 1];
960
453k
                        copy = 3 + BITS(2);
961
453k
                        DROPBITS(2);
962
453k
                    }
963
2.17M
                    else if (here.val == 17) {
964
1.39M
                        NEEDBITS(here.bits + 3);
965
1.38M
                        DROPBITS(here.bits);
966
1.38M
                        len = 0;
967
1.38M
                        copy = 3 + BITS(3);
968
1.38M
                        DROPBITS(3);
969
1.38M
                    }
970
785k
                    else {
971
785k
                        NEEDBITS(here.bits + 7);
972
784k
                        DROPBITS(here.bits);
973
784k
                        len = 0;
974
784k
                        copy = 11 + BITS(7);
975
784k
                        DROPBITS(7);
976
784k
                    }
977
2.62M
                    if (state->have + copy > state->nlen + state->ndist) {
978
4.27k
                        strm->msg = (char *)"invalid bit length repeat";
979
4.27k
                        state->mode = BAD;
980
4.27k
                        break;
981
4.27k
                    }
982
50.7M
                    while (copy--)
983
48.1M
                        state->lens[state->have++] = (unsigned short)len;
984
2.62M
                }
985
28.2M
            }
986
987
            /* handle error breaks in while */
988
247k
            if (state->mode == BAD) break;
989
990
            /* check for end-of-block code (better have one) */
991
242k
            if (state->lens[256] == 0) {
992
1.85k
                strm->msg = (char *)"invalid code -- missing end-of-block";
993
1.85k
                state->mode = BAD;
994
1.85k
                break;
995
1.85k
            }
996
997
            /* build code tables -- note: do not change the lenbits or distbits
998
               values here (9 and 6) without reading the comments in inftrees.h
999
               concerning the ENOUGH constants, which depend on those values */
1000
240k
            state->next = state->codes;
1001
240k
            state->lencode = (const code FAR *)(state->next);
1002
240k
            state->lenbits = 9;
1003
240k
            ret = inflate_table(LENS, state->lens, state->nlen, &(state->next),
1004
240k
                                &(state->lenbits), state->work);
1005
240k
            if (ret) {
1006
4.69k
                strm->msg = (char *)"invalid literal/lengths set";
1007
4.69k
                state->mode = BAD;
1008
4.69k
                break;
1009
4.69k
            }
1010
236k
            state->distcode = (const code FAR *)(state->next);
1011
236k
            state->distbits = 6;
1012
236k
            ret = inflate_table(DISTS, state->lens + state->nlen, state->ndist,
1013
236k
                            &(state->next), &(state->distbits), state->work);
1014
236k
            if (ret) {
1015
2.30k
                strm->msg = (char *)"invalid distances set";
1016
2.30k
                state->mode = BAD;
1017
2.30k
                break;
1018
2.30k
            }
1019
233k
            Tracev((stderr, "inflate:       codes ok\n"));
1020
233k
            state->mode = LEN_;
1021
233k
            if (flush == Z_TREES) goto inf_leave;
1022
                /* fallthrough */
1023
372k
        case LEN_:
1024
372k
            state->mode = LEN;
1025
                /* fallthrough */
1026
22.8M
        case LEN:
1027
22.8M
            if (have >= 6 && left >= 258) {
1028
1.08M
                RESTORE();
1029
1.08M
                inflate_fast(strm, out);
1030
1.08M
                LOAD();
1031
1.08M
                if (state->mode == TYPE)
1032
26.3k
                    state->back = -1;
1033
1.08M
                break;
1034
1.08M
            }
1035
21.7M
            state->back = 0;
1036
37.5M
            for (;;) {
1037
37.5M
                here = state->lencode[BITS(state->lenbits)];
1038
37.5M
                if ((unsigned)(here.bits) <= bits) break;
1039
15.8M
                PULLBYTE();
1040
15.8M
            }
1041
21.7M
            if (here.op && (here.op & 0xf0) == 0) {
1042
204k
                last = here;
1043
261k
                for (;;) {
1044
261k
                    here = state->lencode[last.val +
1045
261k
                            (BITS(last.bits + last.op) >> last.bits)];
1046
261k
                    if ((unsigned)(last.bits + here.bits) <= bits) break;
1047
59.2k
                    PULLBYTE();
1048
59.2k
                }
1049
202k
                DROPBITS(last.bits);
1050
202k
                state->back += last.bits;
1051
202k
            }
1052
21.7M
            DROPBITS(here.bits);
1053
21.7M
            state->back += here.bits;
1054
21.7M
            state->length = (unsigned)here.val;
1055
21.7M
            if ((int)(here.op) == 0) {
1056
14.0M
                Tracevv((stderr, here.val >= 0x20 && here.val < 0x7f ?
1057
14.0M
                        "inflate:         literal '%c'\n" :
1058
14.0M
                        "inflate:         literal 0x%02x\n", here.val));
1059
14.0M
                state->mode = LIT;
1060
14.0M
                break;
1061
14.0M
            }
1062
7.63M
            if (here.op & 32) {
1063
281k
                Tracevv((stderr, "inflate:         end of block\n"));
1064
281k
                state->back = -1;
1065
281k
                state->mode = TYPE;
1066
281k
                break;
1067
281k
            }
1068
7.35M
            if (here.op & 64) {
1069
1.91k
                strm->msg = (char *)"invalid literal/length code";
1070
1.91k
                state->mode = BAD;
1071
1.91k
                break;
1072
1.91k
            }
1073
7.35M
            state->extra = (unsigned)(here.op) & 15;
1074
7.35M
            state->mode = LENEXT;
1075
                /* fallthrough */
1076
7.35M
        case LENEXT:
1077
7.35M
            if (state->extra) {
1078
3.31M
                NEEDBITS(state->extra);
1079
3.31M
                state->length += BITS(state->extra);
1080
3.31M
                DROPBITS(state->extra);
1081
3.31M
                state->back += state->extra;
1082
3.31M
            }
1083
7.35M
            Tracevv((stderr, "inflate:         length %u\n", state->length));
1084
7.35M
            state->was = state->length;
1085
7.35M
            state->mode = DIST;
1086
                /* fallthrough */
1087
7.35M
        case DIST:
1088
11.6M
            for (;;) {
1089
11.6M
                here = state->distcode[BITS(state->distbits)];
1090
11.6M
                if ((unsigned)(here.bits) <= bits) break;
1091
4.26M
                PULLBYTE();
1092
4.26M
            }
1093
7.35M
            if ((here.op & 0xf0) == 0) {
1094
166k
                last = here;
1095
214k
                for (;;) {
1096
214k
                    here = state->distcode[last.val +
1097
214k
                            (BITS(last.bits + last.op) >> last.bits)];
1098
214k
                    if ((unsigned)(last.bits + here.bits) <= bits) break;
1099
48.3k
                    PULLBYTE();
1100
48.3k
                }
1101
166k
                DROPBITS(last.bits);
1102
166k
                state->back += last.bits;
1103
166k
            }
1104
7.34M
            DROPBITS(here.bits);
1105
7.34M
            state->back += here.bits;
1106
7.34M
            if (here.op & 64) {
1107
3.10k
                strm->msg = (char *)"invalid distance code";
1108
3.10k
                state->mode = BAD;
1109
3.10k
                break;
1110
3.10k
            }
1111
7.34M
            state->offset = (unsigned)here.val;
1112
7.34M
            state->extra = (unsigned)(here.op) & 15;
1113
7.34M
            state->mode = DISTEXT;
1114
                /* fallthrough */
1115
7.35M
        case DISTEXT:
1116
7.35M
            if (state->extra) {
1117
6.02M
                NEEDBITS(state->extra);
1118
6.01M
                state->offset += BITS(state->extra);
1119
6.01M
                DROPBITS(state->extra);
1120
6.01M
                state->back += state->extra;
1121
6.01M
            }
1122
#ifdef INFLATE_STRICT
1123
            if (state->offset > state->dmax) {
1124
                strm->msg = (char *)"invalid distance too far back";
1125
                state->mode = BAD;
1126
                break;
1127
            }
1128
#endif
1129
7.34M
            Tracevv((stderr, "inflate:         distance %u\n", state->offset));
1130
7.34M
            state->mode = MATCH;
1131
                /* fallthrough */
1132
532M
        case MATCH:
1133
532M
            if (left == 0) goto inf_leave;
1134
272M
            copy = out - left;
1135
272M
            if (state->offset > copy) {         /* copy from window */
1136
262M
                copy = state->offset - copy;
1137
262M
                if (copy > state->whave) {
1138
5.30k
                    if (state->sane) {
1139
5.30k
                        strm->msg = (char *)"invalid distance too far back";
1140
5.30k
                        state->mode = BAD;
1141
5.30k
                        break;
1142
5.30k
                    }
1143
#ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR
1144
                    Trace((stderr, "inflate.c too far\n"));
1145
                    copy -= state->whave;
1146
                    if (copy > state->length) copy = state->length;
1147
                    if (copy > left) copy = left;
1148
                    left -= copy;
1149
                    state->length -= copy;
1150
                    do {
1151
                        *put++ = 0;
1152
                    } while (--copy);
1153
                    if (state->length == 0) state->mode = LEN;
1154
                    break;
1155
#endif
1156
5.30k
                }
1157
262M
                if (copy > state->wnext) {
1158
6.07M
                    copy -= state->wnext;
1159
6.07M
                    from = state->window + (state->wsize - copy);
1160
6.07M
                }
1161
256M
                else
1162
256M
                    from = state->window + (state->wnext - copy);
1163
262M
                if (copy > state->length) copy = state->length;
1164
262M
            }
1165
9.68M
            else {                              /* copy from output */
1166
9.68M
                from = put - state->offset;
1167
9.68M
                copy = state->length;
1168
9.68M
            }
1169
272M
            if (copy > left) copy = left;
1170
272M
            left -= copy;
1171
272M
            state->length -= copy;
1172
947M
            do {
1173
947M
                *put++ = *from++;
1174
947M
            } while (--copy);
1175
272M
            if (state->length == 0) state->mode = LEN;
1176
272M
            break;
1177
15.5M
        case LIT:
1178
15.5M
            if (left == 0) goto inf_leave;
1179
14.0M
            *put++ = (unsigned char)(state->length);
1180
14.0M
            left--;
1181
14.0M
            state->mode = LEN;
1182
14.0M
            break;
1183
192k
        case CHECK:
1184
192k
            if (state->wrap) {
1185
15.3k
                NEEDBITS(32);
1186
13.1k
                out -= left;
1187
13.1k
                strm->total_out += out;
1188
13.1k
                state->total += out;
1189
13.1k
                if ((state->wrap & 4) && out)
1190
10.4k
                    strm->adler = state->check =
1191
10.4k
                        UPDATE_CHECK(state->check, put - out, out);
1192
13.1k
                out = left;
1193
13.1k
                if ((state->wrap & 4) && (
1194
13.1k
#ifdef GUNZIP
1195
13.1k
                     state->flags ? hold :
1196
13.1k
#endif
1197
13.1k
                     ZSWAP32(hold)) != state->check) {
1198
4.47k
                    strm->msg = (char *)"incorrect data check";
1199
4.47k
                    state->mode = BAD;
1200
4.47k
                    break;
1201
4.47k
                }
1202
8.65k
                INITBITS();
1203
8.65k
                Tracev((stderr, "inflate:   check matches trailer\n"));
1204
8.65k
            }
1205
185k
#ifdef GUNZIP
1206
185k
            state->mode = LENGTH;
1207
                /* fallthrough */
1208
185k
        case LENGTH:
1209
185k
            if (state->wrap && state->flags) {
1210
0
                NEEDBITS(32);
1211
0
                if ((state->wrap & 4) && hold != (state->total & 0xffffffff)) {
1212
0
                    strm->msg = (char *)"incorrect length check";
1213
0
                    state->mode = BAD;
1214
0
                    break;
1215
0
                }
1216
0
                INITBITS();
1217
0
                Tracev((stderr, "inflate:   length matches trailer\n"));
1218
0
            }
1219
185k
#endif
1220
185k
            state->mode = DONE;
1221
                /* fallthrough */
1222
193k
        case DONE:
1223
193k
            ret = Z_STREAM_END;
1224
193k
            goto inf_leave;
1225
60.8k
        case BAD:
1226
60.8k
            ret = Z_DATA_ERROR;
1227
60.8k
            goto inf_leave;
1228
0
        case MEM:
1229
0
            return Z_MEM_ERROR;
1230
0
        case SYNC:
1231
                /* fallthrough */
1232
0
        default:
1233
0
            return Z_STREAM_ERROR;
1234
565M
        }
1235
1236
    /*
1237
       Return from inflate(), updating the total counts and the check value.
1238
       If there was no progress during the inflate() call, return a buffer
1239
       error.  Call updatewindow() to create and/or update the window state.
1240
       Note: a memory error from inflate() is non-recoverable.
1241
     */
1242
262M
  inf_leave:
1243
262M
    RESTORE();
1244
262M
    if (state->wsize || (out != strm->avail_out && state->mode < BAD &&
1245
236k
            (state->mode < CHECK || flush != Z_FINISH)))
1246
262M
        if (updatewindow(strm, strm->next_out, out - strm->avail_out)) {
1247
0
            state->mode = MEM;
1248
0
            return Z_MEM_ERROR;
1249
0
        }
1250
262M
    in -= strm->avail_in;
1251
262M
    out -= strm->avail_out;
1252
262M
    strm->total_in += in;
1253
262M
    strm->total_out += out;
1254
262M
    state->total += out;
1255
262M
    if ((state->wrap & 4) && out)
1256
5.59M
        strm->adler = state->check =
1257
5.59M
            UPDATE_CHECK(state->check, strm->next_out - out, out);
1258
262M
    strm->data_type = (int)state->bits + (state->last ? 64 : 0) +
1259
262M
                      (state->mode == TYPE ? 128 : 0) +
1260
262M
                      (state->mode == LEN_ || state->mode == COPY_ ? 256 : 0);
1261
262M
    if (((in == 0 && out == 0) || flush == Z_FINISH) && ret == Z_OK)
1262
237k
        ret = Z_BUF_ERROR;
1263
262M
    return ret;
1264
262M
}
1265
1266
273k
int ZEXPORT inflateEnd(z_streamp strm) {
1267
273k
    struct inflate_state FAR *state;
1268
273k
    if (inflateStateCheck(strm))
1269
4.99k
        return Z_STREAM_ERROR;
1270
268k
    state = (struct inflate_state FAR *)strm->state;
1271
268k
    if (state->window != Z_NULL) ZFREE(strm, state->window);
1272
268k
    ZFREE(strm, strm->state);
1273
268k
    strm->state = Z_NULL;
1274
268k
    Tracev((stderr, "inflate: end\n"));
1275
268k
    return Z_OK;
1276
273k
}
1277
1278
int ZEXPORT inflateGetDictionary(z_streamp strm, Bytef *dictionary,
1279
0
                                 uInt *dictLength) {
1280
0
    struct inflate_state FAR *state;
1281
1282
    /* check state */
1283
0
    if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
1284
0
    state = (struct inflate_state FAR *)strm->state;
1285
1286
    /* copy dictionary */
1287
0
    if (state->whave && dictionary != Z_NULL) {
1288
0
        zmemcpy(dictionary, state->window + state->wnext,
1289
0
                state->whave - state->wnext);
1290
0
        zmemcpy(dictionary + state->whave - state->wnext,
1291
0
                state->window, state->wnext);
1292
0
    }
1293
0
    if (dictLength != Z_NULL)
1294
0
        *dictLength = state->whave;
1295
0
    return Z_OK;
1296
0
}
1297
1298
int ZEXPORT inflateSetDictionary(z_streamp strm, const Bytef *dictionary,
1299
0
                                 uInt dictLength) {
1300
0
    struct inflate_state FAR *state;
1301
0
    unsigned long dictid;
1302
0
    int ret;
1303
1304
    /* check state */
1305
0
    if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
1306
0
    state = (struct inflate_state FAR *)strm->state;
1307
0
    if (state->wrap != 0 && state->mode != DICT)
1308
0
        return Z_STREAM_ERROR;
1309
1310
    /* check for correct dictionary identifier */
1311
0
    if (state->mode == DICT) {
1312
0
        dictid = adler32(0L, Z_NULL, 0);
1313
0
        dictid = adler32(dictid, dictionary, dictLength);
1314
0
        if (dictid != state->check)
1315
0
            return Z_DATA_ERROR;
1316
0
    }
1317
1318
    /* copy dictionary to window using updatewindow(), which will amend the
1319
       existing dictionary if appropriate */
1320
0
    ret = updatewindow(strm, dictionary + dictLength, dictLength);
1321
0
    if (ret) {
1322
0
        state->mode = MEM;
1323
0
        return Z_MEM_ERROR;
1324
0
    }
1325
0
    state->havedict = 1;
1326
0
    Tracev((stderr, "inflate:   dictionary set\n"));
1327
0
    return Z_OK;
1328
0
}
1329
1330
0
int ZEXPORT inflateGetHeader(z_streamp strm, gz_headerp head) {
1331
0
    struct inflate_state FAR *state;
1332
1333
    /* check state */
1334
0
    if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
1335
0
    state = (struct inflate_state FAR *)strm->state;
1336
0
    if ((state->wrap & 2) == 0) return Z_STREAM_ERROR;
1337
1338
    /* save header structure */
1339
0
    state->head = head;
1340
0
    head->done = 0;
1341
0
    return Z_OK;
1342
0
}
1343
1344
/*
1345
   Search buf[0..len-1] for the pattern: 0, 0, 0xff, 0xff.  Return when found
1346
   or when out of input.  When called, *have is the number of pattern bytes
1347
   found in order so far, in 0..3.  On return *have is updated to the new
1348
   state.  If on return *have equals four, then the pattern was found and the
1349
   return value is how many bytes were read including the last byte of the
1350
   pattern.  If *have is less than four, then the pattern has not been found
1351
   yet and the return value is len.  In the latter case, syncsearch() can be
1352
   called again with more data and the *have state.  *have is initialized to
1353
   zero for the first call.
1354
 */
1355
local unsigned syncsearch(unsigned FAR *have, const unsigned char FAR *buf,
1356
0
                          unsigned len) {
1357
0
    unsigned got;
1358
0
    unsigned next;
1359
1360
0
    got = *have;
1361
0
    next = 0;
1362
0
    while (next < len && got < 4) {
1363
0
        if ((int)(buf[next]) == (got < 2 ? 0 : 0xff))
1364
0
            got++;
1365
0
        else if (buf[next])
1366
0
            got = 0;
1367
0
        else
1368
0
            got = 4 - got;
1369
0
        next++;
1370
0
    }
1371
0
    *have = got;
1372
0
    return next;
1373
0
}
1374
1375
0
int ZEXPORT inflateSync(z_streamp strm) {
1376
0
    unsigned len;               /* number of bytes to look at or looked at */
1377
0
    int flags;                  /* temporary to save header status */
1378
0
    unsigned long in, out;      /* temporary to save total_in and total_out */
1379
0
    unsigned char buf[4];       /* to restore bit buffer to byte string */
1380
0
    struct inflate_state FAR *state;
1381
1382
    /* check parameters */
1383
0
    if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
1384
0
    state = (struct inflate_state FAR *)strm->state;
1385
0
    if (strm->avail_in == 0 && state->bits < 8) return Z_BUF_ERROR;
1386
1387
    /* if first time, start search in bit buffer */
1388
0
    if (state->mode != SYNC) {
1389
0
        state->mode = SYNC;
1390
0
        state->hold >>= state->bits & 7;
1391
0
        state->bits -= state->bits & 7;
1392
0
        len = 0;
1393
0
        while (state->bits >= 8) {
1394
0
            buf[len++] = (unsigned char)(state->hold);
1395
0
            state->hold >>= 8;
1396
0
            state->bits -= 8;
1397
0
        }
1398
0
        state->have = 0;
1399
0
        syncsearch(&(state->have), buf, len);
1400
0
    }
1401
1402
    /* search available input */
1403
0
    len = syncsearch(&(state->have), strm->next_in, strm->avail_in);
1404
0
    strm->avail_in -= len;
1405
0
    strm->next_in += len;
1406
0
    strm->total_in += len;
1407
1408
    /* return no joy or set up to restart inflate() on a new block */
1409
0
    if (state->have != 4) return Z_DATA_ERROR;
1410
0
    if (state->flags == -1)
1411
0
        state->wrap = 0;    /* if no header yet, treat as raw */
1412
0
    else
1413
0
        state->wrap &= ~4;  /* no point in computing a check value now */
1414
0
    flags = state->flags;
1415
0
    in = strm->total_in;  out = strm->total_out;
1416
0
    inflateReset(strm);
1417
0
    strm->total_in = in;  strm->total_out = out;
1418
0
    state->flags = flags;
1419
0
    state->mode = TYPE;
1420
0
    return Z_OK;
1421
0
}
1422
1423
/*
1424
   Returns true if inflate is currently at the end of a block generated by
1425
   Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
1426
   implementation to provide an additional safety check. PPP uses
1427
   Z_SYNC_FLUSH but removes the length bytes of the resulting empty stored
1428
   block. When decompressing, PPP checks that at the end of input packet,
1429
   inflate is waiting for these length bytes.
1430
 */
1431
0
int ZEXPORT inflateSyncPoint(z_streamp strm) {
1432
0
    struct inflate_state FAR *state;
1433
1434
0
    if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
1435
0
    state = (struct inflate_state FAR *)strm->state;
1436
0
    return state->mode == STORED && state->bits == 0;
1437
0
}
1438
1439
0
int ZEXPORT inflateCopy(z_streamp dest, z_streamp source) {
1440
0
    struct inflate_state FAR *state;
1441
0
    struct inflate_state FAR *copy;
1442
0
    unsigned char FAR *window;
1443
0
    unsigned wsize;
1444
1445
    /* check input */
1446
0
    if (inflateStateCheck(source) || dest == Z_NULL)
1447
0
        return Z_STREAM_ERROR;
1448
0
    state = (struct inflate_state FAR *)source->state;
1449
1450
    /* allocate space */
1451
0
    copy = (struct inflate_state FAR *)
1452
0
           ZALLOC(source, 1, sizeof(struct inflate_state));
1453
0
    if (copy == Z_NULL) return Z_MEM_ERROR;
1454
0
    window = Z_NULL;
1455
0
    if (state->window != Z_NULL) {
1456
0
        window = (unsigned char FAR *)
1457
0
                 ZALLOC(source, 1U << state->wbits, sizeof(unsigned char));
1458
0
        if (window == Z_NULL) {
1459
0
            ZFREE(source, copy);
1460
0
            return Z_MEM_ERROR;
1461
0
        }
1462
0
    }
1463
1464
    /* copy state */
1465
0
    zmemcpy((voidpf)dest, (voidpf)source, sizeof(z_stream));
1466
0
    zmemcpy((voidpf)copy, (voidpf)state, sizeof(struct inflate_state));
1467
0
    copy->strm = dest;
1468
0
    if (state->lencode >= state->codes &&
1469
0
        state->lencode <= state->codes + ENOUGH - 1) {
1470
0
        copy->lencode = copy->codes + (state->lencode - state->codes);
1471
0
        copy->distcode = copy->codes + (state->distcode - state->codes);
1472
0
    }
1473
0
    copy->next = copy->codes + (state->next - state->codes);
1474
0
    if (window != Z_NULL) {
1475
0
        wsize = 1U << state->wbits;
1476
0
        zmemcpy(window, state->window, wsize);
1477
0
    }
1478
0
    copy->window = window;
1479
0
    dest->state = (struct internal_state FAR *)copy;
1480
0
    return Z_OK;
1481
0
}
1482
1483
0
int ZEXPORT inflateUndermine(z_streamp strm, int subvert) {
1484
0
    struct inflate_state FAR *state;
1485
1486
0
    if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
1487
0
    state = (struct inflate_state FAR *)strm->state;
1488
#ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR
1489
    state->sane = !subvert;
1490
    return Z_OK;
1491
#else
1492
0
    (void)subvert;
1493
0
    state->sane = 1;
1494
0
    return Z_DATA_ERROR;
1495
0
#endif
1496
0
}
1497
1498
0
int ZEXPORT inflateValidate(z_streamp strm, int check) {
1499
0
    struct inflate_state FAR *state;
1500
1501
0
    if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
1502
0
    state = (struct inflate_state FAR *)strm->state;
1503
0
    if (check && state->wrap)
1504
0
        state->wrap |= 4;
1505
0
    else
1506
0
        state->wrap &= ~4;
1507
0
    return Z_OK;
1508
0
}
1509
1510
0
long ZEXPORT inflateMark(z_streamp strm) {
1511
0
    struct inflate_state FAR *state;
1512
1513
0
    if (inflateStateCheck(strm))
1514
0
        return -(1L << 16);
1515
0
    state = (struct inflate_state FAR *)strm->state;
1516
0
    return (long)(((unsigned long)((long)state->back)) << 16) +
1517
0
        (state->mode == COPY ? state->length :
1518
0
            (state->mode == MATCH ? state->was - state->length : 0));
1519
0
}
1520
1521
0
unsigned long ZEXPORT inflateCodesUsed(z_streamp strm) {
1522
0
    struct inflate_state FAR *state;
1523
0
    if (inflateStateCheck(strm)) return (unsigned long)-1;
1524
0
    state = (struct inflate_state FAR *)strm->state;
1525
0
    return (unsigned long)(state->next - state->codes);
1526
0
}