Coverage Report

Created: 2026-02-14 09:37

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
211M
local int inflateStateCheck(z_streamp strm) {
95
211M
    struct inflate_state FAR *state;
96
211M
    if (strm == Z_NULL ||
97
211M
        strm->zalloc == (alloc_func)0 || strm->zfree == (free_func)0)
98
0
        return 1;
99
211M
    state = (struct inflate_state FAR *)strm->state;
100
211M
    if (state == Z_NULL || state->strm != strm ||
101
211M
        state->mode < HEAD || state->mode > SYNC)
102
4.57k
        return 1;
103
211M
    return 0;
104
211M
}
105
106
274k
int ZEXPORT inflateResetKeep(z_streamp strm) {
107
274k
    struct inflate_state FAR *state;
108
109
274k
    if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
110
274k
    state = (struct inflate_state FAR *)strm->state;
111
274k
    strm->total_in = strm->total_out = state->total = 0;
112
274k
    strm->msg = Z_NULL;
113
274k
    if (state->wrap)        /* to support ill-conceived Java test suite */
114
87.2k
        strm->adler = state->wrap & 1;
115
274k
    state->mode = HEAD;
116
274k
    state->last = 0;
117
274k
    state->havedict = 0;
118
274k
    state->flags = -1;
119
274k
    state->dmax = 32768U;
120
274k
    state->head = Z_NULL;
121
274k
    state->hold = 0;
122
274k
    state->bits = 0;
123
274k
    state->lencode = state->distcode = state->next = state->codes;
124
274k
    state->sane = 1;
125
274k
    state->back = -1;
126
274k
    Tracev((stderr, "inflate: reset\n"));
127
274k
    return Z_OK;
128
274k
}
129
130
274k
int ZEXPORT inflateReset(z_streamp strm) {
131
274k
    struct inflate_state FAR *state;
132
133
274k
    if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
134
274k
    state = (struct inflate_state FAR *)strm->state;
135
274k
    state->wsize = 0;
136
274k
    state->whave = 0;
137
274k
    state->wnext = 0;
138
274k
    return inflateResetKeep(strm);
139
274k
}
140
141
269k
int ZEXPORT inflateReset2(z_streamp strm, int windowBits) {
142
269k
    int wrap;
143
269k
    struct inflate_state FAR *state;
144
145
    /* get the state */
146
269k
    if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
147
269k
    state = (struct inflate_state FAR *)strm->state;
148
149
    /* extract wrap request from windowBits parameter */
150
269k
    if (windowBits < 0) {
151
187k
        if (windowBits < -15)
152
0
            return Z_STREAM_ERROR;
153
187k
        wrap = 0;
154
187k
        windowBits = -windowBits;
155
187k
    }
156
82.7k
    else {
157
82.7k
        wrap = (windowBits >> 4) + 5;
158
82.7k
#ifdef GUNZIP
159
82.7k
        if (windowBits < 48)
160
82.7k
            windowBits &= 15;
161
82.7k
#endif
162
82.7k
    }
163
164
    /* set number of window bits, free window if different */
165
269k
    if (windowBits && (windowBits < 8 || windowBits > 15))
166
0
        return Z_STREAM_ERROR;
167
269k
    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
269k
    state->wrap = wrap;
174
269k
    state->wbits = (unsigned)windowBits;
175
269k
    return inflateReset(strm);
176
269k
}
177
178
int ZEXPORT inflateInit2_(z_streamp strm, int windowBits,
179
238k
                          const char *version, int stream_size) {
180
238k
    int ret;
181
238k
    struct inflate_state FAR *state;
182
183
238k
    if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
184
238k
        stream_size != (int)(sizeof(z_stream)))
185
0
        return Z_VERSION_ERROR;
186
238k
    if (strm == Z_NULL) return Z_STREAM_ERROR;
187
238k
    strm->msg = Z_NULL;                 /* in case we return an error */
188
238k
    if (strm->zalloc == (alloc_func)0) {
189
#ifdef Z_SOLO
190
        return Z_STREAM_ERROR;
191
#else
192
223k
        strm->zalloc = zcalloc;
193
223k
        strm->opaque = (voidpf)0;
194
223k
#endif
195
223k
    }
196
238k
    if (strm->zfree == (free_func)0)
197
#ifdef Z_SOLO
198
        return Z_STREAM_ERROR;
199
#else
200
223k
        strm->zfree = zcfree;
201
238k
#endif
202
238k
    state = (struct inflate_state FAR *)
203
238k
            ZALLOC(strm, 1, sizeof(struct inflate_state));
204
238k
    if (state == Z_NULL) return Z_MEM_ERROR;
205
238k
    Tracev((stderr, "inflate: allocated\n"));
206
238k
    strm->state = (struct internal_state FAR *)state;
207
238k
    state->strm = strm;
208
238k
    state->window = Z_NULL;
209
238k
    state->mode = HEAD;     /* to pass state test in inflateReset2() */
210
238k
    ret = inflateReset2(strm, windowBits);
211
238k
    if (ret != Z_OK) {
212
0
        ZFREE(strm, state);
213
0
        strm->state = Z_NULL;
214
0
    }
215
238k
    return ret;
216
238k
}
217
218
int ZEXPORT inflateInit_(z_streamp strm, const char *version,
219
40.1k
                         int stream_size) {
220
40.1k
    return inflateInit2_(strm, DEF_WBITS, version, stream_size);
221
40.1k
}
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
138k
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
138k
#   include "inffixed.h"
286
138k
#endif /* BUILDFIXED */
287
138k
    state->lencode = lenfix;
288
138k
    state->lenbits = 9;
289
138k
    state->distcode = distfix;
290
138k
    state->distbits = 5;
291
138k
}
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
210M
local int updatewindow(z_streamp strm, const Bytef *end, unsigned copy) {
369
210M
    struct inflate_state FAR *state;
370
210M
    unsigned dist;
371
372
210M
    state = (struct inflate_state FAR *)strm->state;
373
374
    /* if it hasn't been done already, allocate space for the window */
375
210M
    if (state->window == Z_NULL) {
376
200k
        state->window = (unsigned char FAR *)
377
200k
                        ZALLOC(strm, 1U << state->wbits,
378
200k
                               sizeof(unsigned char));
379
200k
        if (state->window == Z_NULL) return 1;
380
200k
    }
381
382
    /* if window not in use yet, initialize */
383
210M
    if (state->wsize == 0) {
384
213k
        state->wsize = 1U << state->wbits;
385
213k
        state->wnext = 0;
386
213k
        state->whave = 0;
387
213k
    }
388
389
    /* copy state->wsize or less output bytes into the circular window */
390
210M
    if (copy >= state->wsize) {
391
33.7k
        zmemcpy(state->window, end - state->wsize, state->wsize);
392
33.7k
        state->wnext = 0;
393
33.7k
        state->whave = state->wsize;
394
33.7k
    }
395
210M
    else {
396
210M
        dist = state->wsize - state->wnext;
397
210M
        if (dist > copy) dist = copy;
398
210M
        zmemcpy(state->window + state->wnext, end - copy, dist);
399
210M
        copy -= dist;
400
210M
        if (copy) {
401
38.8k
            zmemcpy(state->window, end - copy, copy);
402
38.8k
            state->wnext = copy;
403
38.8k
            state->whave = state->wsize;
404
38.8k
        }
405
210M
        else {
406
210M
            state->wnext += dist;
407
210M
            if (state->wnext == state->wsize) state->wnext = 0;
408
210M
            if (state->whave < state->wsize) state->whave += dist;
409
210M
        }
410
210M
    }
411
210M
    return 0;
412
210M
}
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
4.56M
    (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
211M
    do { \
446
211M
        put = strm->next_out; \
447
211M
        left = strm->avail_out; \
448
211M
        next = strm->next_in; \
449
211M
        have = strm->avail_in; \
450
211M
        hold = state->hold; \
451
211M
        bits = state->bits; \
452
211M
    } while (0)
453
454
/* Restore state from registers in inflate() */
455
#define RESTORE() \
456
211M
    do { \
457
211M
        strm->next_out = put; \
458
211M
        strm->avail_out = left; \
459
211M
        strm->next_in = next; \
460
211M
        strm->avail_in = have; \
461
211M
        state->hold = hold; \
462
211M
        state->bits = bits; \
463
211M
    } while (0)
464
465
/* Clear the input bit accumulator */
466
#define INITBITS() \
467
186k
    do { \
468
186k
        hold = 0; \
469
186k
        bits = 0; \
470
186k
    } 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
35.3M
    do { \
476
35.3M
        if (have == 0) goto inf_leave; \
477
35.3M
        have--; \
478
35.1M
        hold += (unsigned long)(*next++) << bits; \
479
35.1M
        bits += 8; \
480
35.1M
    } 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
14.6M
    do { \
486
22.7M
        while (bits < (unsigned)(n)) \
487
14.6M
            PULLBYTE(); \
488
14.6M
    } while (0)
489
490
/* Return the low n bits of the bit accumulator (n < 16) */
491
#define BITS(n) \
492
93.5M
    ((unsigned)hold & ((1U << (n)) - 1))
493
494
/* Remove n bits from the bit accumulator */
495
#define DROPBITS(n) \
496
66.3M
    do { \
497
66.3M
        hold >>= (n); \
498
66.3M
        bits -= (unsigned)(n); \
499
66.3M
    } while (0)
500
501
/* Remove zero to seven bits as needed to go to a byte boundary */
502
#define BYTEBITS() \
503
270k
    do { \
504
270k
        hold >>= bits & 7; \
505
270k
        bits -= bits & 7; \
506
270k
    } 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
210M
int ZEXPORT inflate(z_streamp strm, int flush) {
591
210M
    struct inflate_state FAR *state;
592
210M
    z_const unsigned char FAR *next;    /* next input */
593
210M
    unsigned char FAR *put;     /* next output */
594
210M
    unsigned have, left;        /* available input and output */
595
210M
    unsigned long hold;         /* bit buffer */
596
210M
    unsigned bits;              /* bits in bit buffer */
597
210M
    unsigned in, out;           /* save starting available input and output */
598
210M
    unsigned copy;              /* number of stored or match bytes to copy */
599
210M
    unsigned char FAR *from;    /* where to copy match bytes from */
600
210M
    code here;                  /* current decoding table entry */
601
210M
    code last;                  /* parent table entry */
602
210M
    unsigned len;               /* length to copy for repeats, bits to drop */
603
210M
    int ret;                    /* return code */
604
210M
#ifdef GUNZIP
605
210M
    unsigned char hbuf[4];      /* buffer for gzip header crc calculation */
606
210M
#endif
607
210M
    static const unsigned short order[19] = /* permutation of code lengths */
608
210M
        {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
609
610
210M
    if (inflateStateCheck(strm) || strm->next_out == Z_NULL ||
611
210M
        (strm->next_in == Z_NULL && strm->avail_in != 0))
612
0
        return Z_STREAM_ERROR;
613
614
210M
    state = (struct inflate_state FAR *)strm->state;
615
210M
    if (state->mode == TYPE) state->mode = TYPEDO;      /* skip check */
616
210M
    LOAD();
617
210M
    in = have;
618
210M
    out = left;
619
210M
    ret = Z_OK;
620
210M
    for (;;)
621
457M
        switch (state->mode) {
622
273k
        case HEAD:
623
273k
            if (state->wrap == 0) {
624
186k
                state->mode = TYPEDO;
625
186k
                break;
626
186k
            }
627
87.0k
            NEEDBITS(16);
628
85.9k
#ifdef GUNZIP
629
85.9k
            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
85.9k
            if (state->head != Z_NULL)
639
0
                state->head->done = -1;
640
85.9k
            if (!(state->wrap & 1) ||   /* check if zlib header allowed */
641
#else
642
            if (
643
#endif
644
85.9k
                ((BITS(8) << 8) + (hold >> 8)) % 31) {
645
3.37k
                strm->msg = (char *)"incorrect header check";
646
3.37k
                state->mode = BAD;
647
3.37k
                break;
648
3.37k
            }
649
82.6k
            if (BITS(4) != Z_DEFLATED) {
650
1.20k
                strm->msg = (char *)"unknown compression method";
651
1.20k
                state->mode = BAD;
652
1.20k
                break;
653
1.20k
            }
654
81.3k
            DROPBITS(4);
655
81.3k
            len = BITS(4) + 8;
656
81.3k
            if (state->wbits == 0)
657
0
                state->wbits = len;
658
81.3k
            if (len > 15 || len > state->wbits) {
659
252
                strm->msg = (char *)"invalid window size";
660
252
                state->mode = BAD;
661
252
                break;
662
252
            }
663
81.1k
            state->dmax = 1U << len;
664
81.1k
            state->flags = 0;               /* indicate zlib header */
665
81.1k
            Tracev((stderr, "inflate:   zlib header ok\n"));
666
81.1k
            strm->adler = state->check = adler32(0L, Z_NULL, 0);
667
81.1k
            state->mode = hold & 0x200 ? DICTID : TYPE;
668
81.1k
            INITBITS();
669
81.1k
            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
555
        case DICTID:
811
555
            NEEDBITS(32);
812
288
            strm->adler = state->check = ZSWAP32(hold);
813
288
            INITBITS();
814
288
            state->mode = DICT;
815
                /* fallthrough */
816
288
        case DICT:
817
288
            if (state->havedict == 0) {
818
288
                RESTORE();
819
288
                return Z_NEED_DICT;
820
288
            }
821
0
            strm->adler = state->check = adler32(0L, Z_NULL, 0);
822
0
            state->mode = TYPE;
823
                /* fallthrough */
824
454k
        case TYPE:
825
454k
            if (flush == Z_BLOCK || flush == Z_TREES) goto inf_leave;
826
                /* fallthrough */
827
821k
        case TYPEDO:
828
821k
            if (state->last) {
829
172k
                BYTEBITS();
830
172k
                state->mode = CHECK;
831
172k
                break;
832
172k
            }
833
649k
            NEEDBITS(3);
834
467k
            state->last = BITS(1);
835
467k
            DROPBITS(1);
836
467k
            switch (BITS(2)) {
837
96.9k
            case 0:                             /* stored block */
838
96.9k
                Tracev((stderr, "inflate:     stored block%s\n",
839
96.9k
                        state->last ? " (last)" : ""));
840
96.9k
                state->mode = STORED;
841
96.9k
                break;
842
138k
            case 1:                             /* fixed block */
843
138k
                fixedtables(state);
844
138k
                Tracev((stderr, "inflate:     fixed codes block%s\n",
845
138k
                        state->last ? " (last)" : ""));
846
138k
                state->mode = LEN_;             /* decode codes */
847
138k
                if (flush == Z_TREES) {
848
0
                    DROPBITS(2);
849
0
                    goto inf_leave;
850
0
                }
851
138k
                break;
852
231k
            case 2:                             /* dynamic block */
853
231k
                Tracev((stderr, "inflate:     dynamic codes block%s\n",
854
231k
                        state->last ? " (last)" : ""));
855
231k
                state->mode = TABLE;
856
231k
                break;
857
579
            case 3:
858
579
                strm->msg = (char *)"invalid block type";
859
579
                state->mode = BAD;
860
467k
            }
861
467k
            DROPBITS(2);
862
467k
            break;
863
98.2k
        case STORED:
864
98.2k
            BYTEBITS();                         /* go to byte boundary */
865
98.2k
            NEEDBITS(32);
866
95.9k
            if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) {
867
2.36k
                strm->msg = (char *)"invalid stored block lengths";
868
2.36k
                state->mode = BAD;
869
2.36k
                break;
870
2.36k
            }
871
93.5k
            state->length = (unsigned)hold & 0xffff;
872
93.5k
            Tracev((stderr, "inflate:       stored length %u\n",
873
93.5k
                    state->length));
874
93.5k
            INITBITS();
875
93.5k
            state->mode = COPY_;
876
93.5k
            if (flush == Z_TREES) goto inf_leave;
877
                /* fallthrough */
878
93.5k
        case COPY_:
879
93.5k
            state->mode = COPY;
880
                /* fallthrough */
881
167k
        case COPY:
882
167k
            copy = state->length;
883
167k
            if (copy) {
884
75.9k
                if (copy > have) copy = have;
885
75.9k
                if (copy > left) copy = left;
886
75.9k
                if (copy == 0) goto inf_leave;
887
37.5k
                zmemcpy(put, next, copy);
888
37.5k
                have -= copy;
889
37.5k
                next += copy;
890
37.5k
                left -= copy;
891
37.5k
                put += copy;
892
37.5k
                state->length -= copy;
893
37.5k
                break;
894
75.9k
            }
895
91.5k
            Tracev((stderr, "inflate:       stored end\n"));
896
91.5k
            state->mode = TYPE;
897
91.5k
            break;
898
231k
        case TABLE:
899
231k
            NEEDBITS(14);
900
230k
            state->nlen = BITS(5) + 257;
901
230k
            DROPBITS(5);
902
230k
            state->ndist = BITS(5) + 1;
903
230k
            DROPBITS(5);
904
230k
            state->ncode = BITS(4) + 4;
905
230k
            DROPBITS(4);
906
230k
#ifndef PKZIP_BUG_WORKAROUND
907
230k
            if (state->nlen > 286 || state->ndist > 30) {
908
917
                strm->msg = (char *)"too many length or distance symbols";
909
917
                state->mode = BAD;
910
917
                break;
911
917
            }
912
229k
#endif
913
229k
            Tracev((stderr, "inflate:       table sizes ok\n"));
914
229k
            state->have = 0;
915
229k
            state->mode = LENLENS;
916
                /* fallthrough */
917
230k
        case LENLENS:
918
3.71M
            while (state->have < state->ncode) {
919
3.48M
                NEEDBITS(3);
920
3.48M
                state->lens[order[state->have++]] = (unsigned short)BITS(3);
921
3.48M
                DROPBITS(3);
922
3.48M
            }
923
1.10M
            while (state->have < 19)
924
875k
                state->lens[order[state->have++]] = 0;
925
229k
            state->next = state->codes;
926
229k
            state->lencode = (const code FAR *)(state->next);
927
229k
            state->lenbits = 7;
928
229k
            ret = inflate_table(CODES, state->lens, 19, &(state->next),
929
229k
                                &(state->lenbits), state->work);
930
229k
            if (ret) {
931
7.15k
                strm->msg = (char *)"invalid code lengths set";
932
7.15k
                state->mode = BAD;
933
7.15k
                break;
934
7.15k
            }
935
221k
            Tracev((stderr, "inflate:       code lengths ok\n"));
936
221k
            state->have = 0;
937
221k
            state->mode = CODELENS;
938
                /* fallthrough */
939
226k
        case CODELENS:
940
25.2M
            while (state->have < state->nlen + state->ndist) {
941
34.3M
                for (;;) {
942
34.3M
                    here = state->lencode[BITS(state->lenbits)];
943
34.3M
                    if ((unsigned)(here.bits) <= bits) break;
944
9.39M
                    PULLBYTE();
945
9.39M
                }
946
24.9M
                if (here.val < 16) {
947
22.6M
                    DROPBITS(here.bits);
948
22.6M
                    state->lens[state->have++] = here.val;
949
22.6M
                }
950
2.33M
                else {
951
2.33M
                    if (here.val == 16) {
952
442k
                        NEEDBITS(here.bits + 2);
953
441k
                        DROPBITS(here.bits);
954
441k
                        if (state->have == 0) {
955
1.28k
                            strm->msg = (char *)"invalid bit length repeat";
956
1.28k
                            state->mode = BAD;
957
1.28k
                            break;
958
1.28k
                        }
959
440k
                        len = state->lens[state->have - 1];
960
440k
                        copy = 3 + BITS(2);
961
440k
                        DROPBITS(2);
962
440k
                    }
963
1.89M
                    else if (here.val == 17) {
964
1.21M
                        NEEDBITS(here.bits + 3);
965
1.21M
                        DROPBITS(here.bits);
966
1.21M
                        len = 0;
967
1.21M
                        copy = 3 + BITS(3);
968
1.21M
                        DROPBITS(3);
969
1.21M
                    }
970
676k
                    else {
971
676k
                        NEEDBITS(here.bits + 7);
972
676k
                        DROPBITS(here.bits);
973
676k
                        len = 0;
974
676k
                        copy = 11 + BITS(7);
975
676k
                        DROPBITS(7);
976
676k
                    }
977
2.33M
                    if (state->have + copy > state->nlen + state->ndist) {
978
4.79k
                        strm->msg = (char *)"invalid bit length repeat";
979
4.79k
                        state->mode = BAD;
980
4.79k
                        break;
981
4.79k
                    }
982
44.6M
                    while (copy--)
983
42.3M
                        state->lens[state->have++] = (unsigned short)len;
984
2.32M
                }
985
24.9M
            }
986
987
            /* handle error breaks in while */
988
219k
            if (state->mode == BAD) break;
989
990
            /* check for end-of-block code (better have one) */
991
212k
            if (state->lens[256] == 0) {
992
1.68k
                strm->msg = (char *)"invalid code -- missing end-of-block";
993
1.68k
                state->mode = BAD;
994
1.68k
                break;
995
1.68k
            }
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
211k
            state->next = state->codes;
1001
211k
            state->lencode = (const code FAR *)(state->next);
1002
211k
            state->lenbits = 9;
1003
211k
            ret = inflate_table(LENS, state->lens, state->nlen, &(state->next),
1004
211k
                                &(state->lenbits), state->work);
1005
211k
            if (ret) {
1006
4.01k
                strm->msg = (char *)"invalid literal/lengths set";
1007
4.01k
                state->mode = BAD;
1008
4.01k
                break;
1009
4.01k
            }
1010
207k
            state->distcode = (const code FAR *)(state->next);
1011
207k
            state->distbits = 6;
1012
207k
            ret = inflate_table(DISTS, state->lens + state->nlen, state->ndist,
1013
207k
                            &(state->next), &(state->distbits), state->work);
1014
207k
            if (ret) {
1015
1.96k
                strm->msg = (char *)"invalid distances set";
1016
1.96k
                state->mode = BAD;
1017
1.96k
                break;
1018
1.96k
            }
1019
205k
            Tracev((stderr, "inflate:       codes ok\n"));
1020
205k
            state->mode = LEN_;
1021
205k
            if (flush == Z_TREES) goto inf_leave;
1022
                /* fallthrough */
1023
343k
        case LEN_:
1024
343k
            state->mode = LEN;
1025
                /* fallthrough */
1026
20.5M
        case LEN:
1027
20.5M
            if (have >= 6 && left >= 258) {
1028
1.09M
                RESTORE();
1029
1.09M
                inflate_fast(strm, out);
1030
1.09M
                LOAD();
1031
1.09M
                if (state->mode == TYPE)
1032
29.1k
                    state->back = -1;
1033
1.09M
                break;
1034
1.09M
            }
1035
19.4M
            state->back = 0;
1036
33.4M
            for (;;) {
1037
33.4M
                here = state->lencode[BITS(state->lenbits)];
1038
33.4M
                if ((unsigned)(here.bits) <= bits) break;
1039
13.9M
                PULLBYTE();
1040
13.9M
            }
1041
19.4M
            if (here.op && (here.op & 0xf0) == 0) {
1042
192k
                last = here;
1043
246k
                for (;;) {
1044
246k
                    here = state->lencode[last.val +
1045
246k
                            (BITS(last.bits + last.op) >> last.bits)];
1046
246k
                    if ((unsigned)(last.bits + here.bits) <= bits) break;
1047
55.2k
                    PULLBYTE();
1048
55.2k
                }
1049
190k
                DROPBITS(last.bits);
1050
190k
                state->back += last.bits;
1051
190k
            }
1052
19.4M
            DROPBITS(here.bits);
1053
19.4M
            state->back += here.bits;
1054
19.4M
            state->length = (unsigned)here.val;
1055
19.4M
            if ((int)(here.op) == 0) {
1056
12.8M
                Tracevv((stderr, here.val >= 0x20 && here.val < 0x7f ?
1057
12.8M
                        "inflate:         literal '%c'\n" :
1058
12.8M
                        "inflate:         literal 0x%02x\n", here.val));
1059
12.8M
                state->mode = LIT;
1060
12.8M
                break;
1061
12.8M
            }
1062
6.64M
            if (here.op & 32) {
1063
253k
                Tracevv((stderr, "inflate:         end of block\n"));
1064
253k
                state->back = -1;
1065
253k
                state->mode = TYPE;
1066
253k
                break;
1067
253k
            }
1068
6.38M
            if (here.op & 64) {
1069
4.41k
                strm->msg = (char *)"invalid literal/length code";
1070
4.41k
                state->mode = BAD;
1071
4.41k
                break;
1072
4.41k
            }
1073
6.38M
            state->extra = (unsigned)(here.op) & 15;
1074
6.38M
            state->mode = LENEXT;
1075
                /* fallthrough */
1076
6.38M
        case LENEXT:
1077
6.38M
            if (state->extra) {
1078
2.67M
                NEEDBITS(state->extra);
1079
2.67M
                state->length += BITS(state->extra);
1080
2.67M
                DROPBITS(state->extra);
1081
2.67M
                state->back += state->extra;
1082
2.67M
            }
1083
6.38M
            Tracevv((stderr, "inflate:         length %u\n", state->length));
1084
6.38M
            state->was = state->length;
1085
6.38M
            state->mode = DIST;
1086
                /* fallthrough */
1087
6.38M
        case DIST:
1088
9.90M
            for (;;) {
1089
9.90M
                here = state->distcode[BITS(state->distbits)];
1090
9.90M
                if ((unsigned)(here.bits) <= bits) break;
1091
3.52M
                PULLBYTE();
1092
3.52M
            }
1093
6.38M
            if ((here.op & 0xf0) == 0) {
1094
160k
                last = here;
1095
208k
                for (;;) {
1096
208k
                    here = state->distcode[last.val +
1097
208k
                            (BITS(last.bits + last.op) >> last.bits)];
1098
208k
                    if ((unsigned)(last.bits + here.bits) <= bits) break;
1099
48.0k
                    PULLBYTE();
1100
48.0k
                }
1101
160k
                DROPBITS(last.bits);
1102
160k
                state->back += last.bits;
1103
160k
            }
1104
6.37M
            DROPBITS(here.bits);
1105
6.37M
            state->back += here.bits;
1106
6.37M
            if (here.op & 64) {
1107
2.92k
                strm->msg = (char *)"invalid distance code";
1108
2.92k
                state->mode = BAD;
1109
2.92k
                break;
1110
2.92k
            }
1111
6.37M
            state->offset = (unsigned)here.val;
1112
6.37M
            state->extra = (unsigned)(here.op) & 15;
1113
6.37M
            state->mode = DISTEXT;
1114
                /* fallthrough */
1115
6.38M
        case DISTEXT:
1116
6.38M
            if (state->extra) {
1117
5.02M
                NEEDBITS(state->extra);
1118
5.02M
                state->offset += BITS(state->extra);
1119
5.02M
                DROPBITS(state->extra);
1120
5.02M
                state->back += state->extra;
1121
5.02M
            }
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
6.37M
            Tracevv((stderr, "inflate:         distance %u\n", state->offset));
1130
6.37M
            state->mode = MATCH;
1131
                /* fallthrough */
1132
427M
        case MATCH:
1133
427M
            if (left == 0) goto inf_leave;
1134
218M
            copy = out - left;
1135
218M
            if (state->offset > copy) {         /* copy from window */
1136
209M
                copy = state->offset - copy;
1137
209M
                if (copy > state->whave) {
1138
5.87k
                    if (state->sane) {
1139
5.87k
                        strm->msg = (char *)"invalid distance too far back";
1140
5.87k
                        state->mode = BAD;
1141
5.87k
                        break;
1142
5.87k
                    }
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
5.87k
                }
1157
209M
                if (copy > state->wnext) {
1158
4.14M
                    copy -= state->wnext;
1159
4.14M
                    from = state->window + (state->wsize - copy);
1160
4.14M
                }
1161
205M
                else
1162
205M
                    from = state->window + (state->wnext - copy);
1163
209M
                if (copy > state->length) copy = state->length;
1164
209M
            }
1165
9.02M
            else {                              /* copy from output */
1166
9.02M
                from = put - state->offset;
1167
9.02M
                copy = state->length;
1168
9.02M
            }
1169
218M
            if (copy > left) copy = left;
1170
218M
            left -= copy;
1171
218M
            state->length -= copy;
1172
815M
            do {
1173
815M
                *put++ = *from++;
1174
815M
            } while (--copy);
1175
218M
            if (state->length == 0) state->mode = LEN;
1176
218M
            break;
1177
14.1M
        case LIT:
1178
14.1M
            if (left == 0) goto inf_leave;
1179
12.7M
            *put++ = (unsigned char)(state->length);
1180
12.7M
            left--;
1181
12.7M
            state->mode = LEN;
1182
12.7M
            break;
1183
173k
        case CHECK:
1184
173k
            if (state->wrap) {
1185
21.4k
                NEEDBITS(32);
1186
19.8k
                out -= left;
1187
19.8k
                strm->total_out += out;
1188
19.8k
                state->total += out;
1189
19.8k
                if ((state->wrap & 4) && out)
1190
15.7k
                    strm->adler = state->check =
1191
15.7k
                        UPDATE_CHECK(state->check, put - out, out);
1192
19.8k
                out = left;
1193
19.8k
                if ((state->wrap & 4) && (
1194
19.8k
#ifdef GUNZIP
1195
19.8k
                     state->flags ? hold :
1196
19.8k
#endif
1197
19.8k
                     ZSWAP32(hold)) != state->check) {
1198
8.22k
                    strm->msg = (char *)"incorrect data check";
1199
8.22k
                    state->mode = BAD;
1200
8.22k
                    break;
1201
8.22k
                }
1202
11.6k
                INITBITS();
1203
11.6k
                Tracev((stderr, "inflate:   check matches trailer\n"));
1204
11.6k
            }
1205
163k
#ifdef GUNZIP
1206
163k
            state->mode = LENGTH;
1207
                /* fallthrough */
1208
163k
        case LENGTH:
1209
163k
            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
163k
#endif
1220
163k
            state->mode = DONE;
1221
                /* fallthrough */
1222
171k
        case DONE:
1223
171k
            ret = Z_STREAM_END;
1224
171k
            goto inf_leave;
1225
69.4k
        case BAD:
1226
69.4k
            ret = Z_DATA_ERROR;
1227
69.4k
            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
457M
        }
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
210M
  inf_leave:
1243
210M
    RESTORE();
1244
210M
    if (state->wsize || (out != strm->avail_out && state->mode < BAD &&
1245
213k
            (state->mode < CHECK || flush != Z_FINISH)))
1246
210M
        if (updatewindow(strm, strm->next_out, out - strm->avail_out)) {
1247
0
            state->mode = MEM;
1248
0
            return Z_MEM_ERROR;
1249
0
        }
1250
210M
    in -= strm->avail_in;
1251
210M
    out -= strm->avail_out;
1252
210M
    strm->total_in += in;
1253
210M
    strm->total_out += out;
1254
210M
    state->total += out;
1255
210M
    if ((state->wrap & 4) && out)
1256
4.54M
        strm->adler = state->check =
1257
4.54M
            UPDATE_CHECK(state->check, strm->next_out - out, out);
1258
210M
    strm->data_type = (int)state->bits + (state->last ? 64 : 0) +
1259
210M
                      (state->mode == TYPE ? 128 : 0) +
1260
210M
                      (state->mode == LEN_ || state->mode == COPY_ ? 256 : 0);
1261
210M
    if (((in == 0 && out == 0) || flush == Z_FINISH) && ret == Z_OK)
1262
205k
        ret = Z_BUF_ERROR;
1263
210M
    return ret;
1264
210M
}
1265
1266
243k
int ZEXPORT inflateEnd(z_streamp strm) {
1267
243k
    struct inflate_state FAR *state;
1268
243k
    if (inflateStateCheck(strm))
1269
4.57k
        return Z_STREAM_ERROR;
1270
238k
    state = (struct inflate_state FAR *)strm->state;
1271
238k
    if (state->window != Z_NULL) ZFREE(strm, state->window);
1272
238k
    ZFREE(strm, strm->state);
1273
238k
    strm->state = Z_NULL;
1274
238k
    Tracev((stderr, "inflate: end\n"));
1275
238k
    return Z_OK;
1276
243k
}
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
}