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1.1 root 1: /* inflate.c -- put in the public domain by Mark Adler */
2:
3: /* Decompresses raw data compressed using the DEFLATE algorithm (RFC 1951) */
4:
5: /* You can do whatever you like with this source file, though I would
6: prefer that if you modify it and redistribute it that you include
7: comments to that effect with your name and the date. Thank you.
8:
9: History:
10: vers date who what
11: ---- --------- -------------- ------------------------------------
12: a ~~ Feb 92 M. Adler used full (large, one-step) lookup table
13: b1 21 Mar 92 M. Adler first version with partial lookup tables
14: b2 21 Mar 92 M. Adler fixed bug in fixed-code blocks
15: b3 22 Mar 92 M. Adler sped up match copies, cleaned up some
16: b4 25 Mar 92 M. Adler added prototypes; removed window[] (now
17: is the responsibility of unzip.h--also
18: changed name to slide[]), so needs diffs
19: for unzip.c and unzip.h (this allows
20: compiling in the small model on MSDOS);
21: fixed cast of q in huft_build();
22: b5 26 Mar 92 M. Adler got rid of unintended macro recursion.
23: b6 27 Mar 92 M. Adler got rid of nextbyte() routine. fixed
24: bug in inflate_fixed().
25: c1 30 Mar 92 M. Adler removed lbits, dbits environment variables.
26: changed BMAX to 16 for explode. Removed
27: OUTB usage, and replaced it with flush()--
28: this was a 20% speed improvement! Added
29: an explode.c (to replace unimplod.c) that
30: uses the huft routines here. Removed
31: register union.
32: c2 4 Apr 92 M. Adler fixed bug for file sizes a multiple of 32k.
33: c3 10 Apr 92 M. Adler reduced memory of code tables made by
34: huft_build significantly (factor of two to
35: three).
36: c4 15 Apr 92 M. Adler added NOMEMCPY do kill use of memcpy().
37: worked around a Turbo C optimization bug.
38: c5 21 Apr 92 M. Adler added the WSIZE #define to allow reducing
39: the 32K window size for specialized
40: applications.
41: c6 31 May 92 M. Adler added some typecasts to eliminate warnings
42: c7 27 Jun 92 G. Roelofs added some more typecasts (444: MSC bug).
43: c8 5 Oct 92 J-l. Gailly added ifdef'd code to deal with PKZIP bug.
44: c9 9 Oct 92 M. Adler removed a memory error message (~line 416).
45: c10 17 Oct 92 G. Roelofs changed ULONG/UWORD/byte to ulg/ush/uch,
46: removed old inflate, renamed inflate_entry
47: to inflate, added Mark's fix to a comment.
48: c10.5 14 Dec 92 M. Adler fix up error messages for incomplete trees.
49: c11 2 Jan 93 M. Adler fixed bug in detection of incomplete
50: tables, and removed assumption that EOB is
51: the longest code (bad assumption).
52: c12 3 Jan 93 M. Adler make tables for fixed blocks only once.
53: c13 5 Jan 93 M. Adler allow all zero length codes (pkzip 2.04c
54: outputs one zero length code for an empty
55: distance tree).
56: c14 12 Mar 93 M. Adler made inflate.c standalone with the
57: introduction of inflate.h.
58: c14b 16 Jul 93 G. Roelofs added (unsigned) typecast to w at 470.
59: c14c 19 Jul 93 J. Bush changed v[N_MAX], l[288], ll[28x+3x] arrays
60: to static for Amiga.
61: c14d 13 Aug 93 J-l. Gailly de-complicatified Mark's c[*p++]++ thing.
62: c14e 8 Oct 93 G. Roelofs changed memset() to memzero().
63: c14f 22 Oct 93 G. Roelofs renamed quietflg to qflag; made Trace()
64: conditional; added inflate_free().
65: c14g 28 Oct 93 G. Roelofs changed l/(lx+1) macro to pointer (Cray bug)
66: c14h 7 Dec 93 C. Ghisler huft_build() optimizations.
67: c14i 9 Jan 94 A. Verheijen set fixed_t{d,l} to NULL after freeing;
68: G. Roelofs check NEXTBYTE macro for EOF.
69: c14j 23 Jan 94 G. Roelofs removed Ghisler "optimizations"; ifdef'd
70: EOF check.
71: c14k 27 Feb 94 G. Roelofs added some typecasts to avoid warnings.
72: c14l 9 Apr 94 G. Roelofs fixed split comments on preprocessor lines
73: to avoid bug in Encore compiler.
74: c14m 7 Jul 94 P. Kienitz modified to allow assembler version of
75: inflate_codes() (define ASM_INFLATECODES)
76: c14n 22 Jul 94 G. Roelofs changed fprintf to macro for DLL versions
77: c14o 23 Aug 94 C. Spieler added a newline to a debug statement;
78: G. Roelofs added another typecast to avoid MSC warning
79: c14p 4 Oct 94 G. Roelofs added (voidp *) cast to free() argument
80: c14q 30 Oct 94 G. Roelofs changed fprintf macro to MESSAGE()
81: c14r 1 Nov 94 G. Roelofs fixed possible redefinition of CHECK_EOF
82: c14s 7 May 95 S. Maxwell OS/2 DLL globals stuff incorporated;
83: P. Kienitz "fixed" ASM_INFLATECODES macro/prototype
84: c14t 18 Aug 95 G. Roelofs added inflate() to use zlib functions;
85: changed voidp to zvoid; moved huft_build()
86: and huft_free() to end of file
87: c14u 1 Oct 95 G. Roelofs moved G into definition of MESSAGE macro
88: c14v 8 Nov 95 P. Kienitz changed ASM_INFLATECODES to use a regular
89: call with __G__ instead of a macro
90: c15 3 Aug 96 M. Adler fixed bomb-bug on random input data (Adobe)
91: c15b 24 Aug 96 M. Adler more fixes for random input data
92: c15c 28 Mar 97 G. Roelofs changed USE_ZLIB fatal exit code from
93: PK_MEM2 to PK_MEM3
94: c16 20 Apr 97 J. Altman added memzero(v[]) in huft_build()
95: c16b 29 Mar 98 C. Spieler modified DLL code for slide redirection
96:
97: fork 12 Dec 07 TrueCrypt Foundation Adapted for TrueCrypt
98: */
99:
100:
101: /*
102: Inflate deflated (PKZIP's method 8 compressed) data. The compression
103: method searches for as much of the current string of bytes (up to a
104: length of 258) in the previous 32K bytes. If it doesn't find any
105: matches (of at least length 3), it codes the next byte. Otherwise, it
106: codes the length of the matched string and its distance backwards from
107: the current position. There is a single Huffman code that codes both
108: single bytes (called "literals") and match lengths. A second Huffman
109: code codes the distance information, which follows a length code. Each
110: length or distance code actually represents a base value and a number
111: of "extra" (sometimes zero) bits to get to add to the base value. At
112: the end of each deflated block is a special end-of-block (EOB) literal/
113: length code. The decoding process is basically: get a literal/length
114: code; if EOB then done; if a literal, emit the decoded byte; if a
115: length then get the distance and emit the referred-to bytes from the
116: sliding window of previously emitted data.
117:
118: There are (currently) three kinds of inflate blocks: stored, fixed, and
119: dynamic. The compressor outputs a chunk of data at a time and decides
120: which method to use on a chunk-by-chunk basis. A chunk might typically
121: be 32K to 64K, uncompressed. If the chunk is uncompressible, then the
122: "stored" method is used. In this case, the bytes are simply stored as
123: is, eight bits per byte, with none of the above coding. The bytes are
124: preceded by a count, since there is no longer an EOB code.
125:
126: If the data are compressible, then either the fixed or dynamic methods
127: are used. In the dynamic method, the compressed data are preceded by
128: an encoding of the literal/length and distance Huffman codes that are
129: to be used to decode this block. The representation is itself Huffman
130: coded, and so is preceded by a description of that code. These code
131: descriptions take up a little space, and so for small blocks, there is
132: a predefined set of codes, called the fixed codes. The fixed method is
133: used if the block ends up smaller that way (usually for quite small
134: chunks); otherwise the dynamic method is used. In the latter case, the
135: codes are customized to the probabilities in the current block and so
136: can code it much better than the pre-determined fixed codes can.
137:
138: The Huffman codes themselves are decoded using a multi-level table
139: lookup, in order to maximize the speed of decoding plus the speed of
140: building the decoding tables. See the comments below that precede the
141: lbits and dbits tuning parameters.
142:
143: GRR: return values(?)
144: 0 OK
145: 1 incomplete table
146: 2 bad input
147: 3 not enough memory
148: */
149:
150:
151: /*
152: Notes beyond the 1.93a appnote.txt:
153:
154: 1. Distance pointers never point before the beginning of the output
155: stream.
156: 2. Distance pointers can point back across blocks, up to 32k away.
157: 3. There is an implied maximum of 7 bits for the bit length table and
158: 15 bits for the actual data.
159: 4. If only one code exists, then it is encoded using one bit. (Zero
160: would be more efficient, but perhaps a little confusing.) If two
161: codes exist, they are coded using one bit each (0 and 1).
162: 5. There is no way of sending zero distance codes--a dummy must be
163: sent if there are none. (History: a pre 2.0 version of PKZIP would
164: store blocks with no distance codes, but this was discovered to be
165: too harsh a criterion.) Valid only for 1.93a. 2.04c does allow
166: zero distance codes, which is sent as one code of zero bits in
167: length.
168: 6. There are up to 286 literal/length codes. Code 256 represents the
169: end-of-block. Note however that the static length tree defines
170: 288 codes just to fill out the Huffman codes. Codes 286 and 287
171: cannot be used though, since there is no length base or extra bits
172: defined for them. Similarily, there are up to 30 distance codes.
173: However, static trees define 32 codes (all 5 bits) to fill out the
174: Huffman codes, but the last two had better not show up in the data.
175: 7. Unzip can check dynamic Huffman blocks for complete code sets.
176: The exception is that a single code would not be complete (see #4).
177: 8. The five bits following the block type is really the number of
178: literal codes sent minus 257.
179: 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
180: (1+6+6). Therefore, to output three times the length, you output
181: three codes (1+1+1), whereas to output four times the same length,
182: you only need two codes (1+3). Hmm.
183: 10. In the tree reconstruction algorithm, Code = Code + Increment
184: only if BitLength(i) is not zero. (Pretty obvious.)
185: 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19)
186: 12. Note: length code 284 can represent 227-258, but length code 285
187: really is 258. The last length deserves its own, short code
188: since it gets used a lot in very redundant files. The length
189: 258 is special since 258 - 3 (the min match length) is 255.
190: 13. The literal/length and distance code bit lengths are read as a
191: single stream of lengths. It is possible (and advantageous) for
192: a repeat code (16, 17, or 18) to go across the boundary between
193: the two sets of lengths.
194: */
195:
196:
197: /* #define DEBUG */
198: #define INFMOD /* tell inflate.h to include code to be compiled */
199: #include "inflate.h"
200:
201:
202: #ifndef WSIZE /* default is 32K */
203: # define WSIZE 0x8000 /* window size--must be a power of two, and at least */
204: #endif /* 32K for zip's deflate method */
205:
206: #if (defined(DLL) && !defined(NO_SLIDE_REDIR))
207: # define wsize G._wsize /* wsize is a variable */
208: #else
209: # define wsize WSIZE /* wsize is a constant */
210: #endif
211:
212:
213: #ifndef NEXTBYTE /* default is to simply get a byte from stdin */
214: # define NEXTBYTE getchar()
215: #endif
216:
217: #ifndef MESSAGE /* only used twice, for fixed strings--NOT general-purpose */
218: # define MESSAGE(str,len,flag) fprintf(stderr,(char *)(str))
219: #endif
220:
221: #ifndef FLUSH /* default is to simply write the buffer to stdout */
222: # define FLUSH(n) fwrite(redirSlide, 1, n, stdout) /* return value not used */
223: #endif
224: /* Warning: the fwrite above might not work on 16-bit compilers, since
225: 0x8000 might be interpreted as -32,768 by the library function. */
226:
227: #ifndef Trace
228: # ifdef DEBUG
229: # define Trace(x) fprintf x
230: # else
231: # define Trace(x)
232: # endif
233: #endif
234:
235: G_struct G;
236: uch redirSlide [WSIZE];
237:
238: /*---------------------------------------------------------------------------*/
239: #ifdef USE_ZLIB
240:
241:
242: /*
243: GRR: return values for both original inflate() and inflate()
244: 0 OK
245: 1 incomplete table(?)
246: 2 bad input
247: 3 not enough memory
248: */
249:
250: /**************************/
251: /* Function inflate() */
252: /**************************/
253:
254: int inflate(__G) /* decompress an inflated entry using the zlib routines */
255: __GDEF
256: {
257: int err=Z_OK;
258:
259: #if (defined(DLL) && !defined(NO_SLIDE_REDIR))
260: if (G.redirect_slide)
261: wsize = G.redirect_size, redirSlide = G.redirect_buffer;
262: else
263: wsize = WSIZE, redirSlide = slide;
264: #endif
265:
266: G.dstrm.next_out = redirSlide;
267: G.dstrm.avail_out = wsize;
268:
269: G.dstrm.next_in = G.inptr;
270: G.dstrm.avail_in = G.incnt;
271:
272: if (!G.inflInit) {
273: unsigned i;
274: int windowBits;
275:
276: /* only need to test this stuff once */
277: if (zlib_version[0] != ZLIB_VERSION[0]) {
278: Info(slide, 0x21, ((char *)slide,
279: "error: incompatible zlib version (expected %s, found %s)\n",
280: ZLIB_VERSION, zlib_version));
281: return 3;
282: } else if (strcmp(zlib_version, ZLIB_VERSION) != 0)
283: Info(slide, 0x21, ((char *)slide,
284: "warning: different zlib version (expected %s, using %s)\n",
285: ZLIB_VERSION, zlib_version));
286:
287: /* windowBits = log2(wsize) */
288: for (i = ((unsigned)wsize * 2 - 1), windowBits = 0;
289: !(i & 1); i >>= 1, ++windowBits);
290: if ((unsigned)windowBits > (unsigned)15)
291: windowBits = 15;
292: else if (windowBits < 8)
293: windowBits = 8;
294:
295: G.dstrm.zalloc = (alloc_func)Z_NULL;
296: G.dstrm.zfree = (free_func)Z_NULL;
297:
298: Trace((stderr, "initializing inflate()\n"));
299: err = inflateInit2(&G.dstrm, -windowBits);
300:
301: if (err == Z_MEM_ERROR)
302: return 3;
303: else if (err != Z_OK)
304: Trace((stderr, "oops! (inflateInit2() err = %d)\n", err));
305: G.inflInit = 1;
306: }
307:
308: #ifdef FUNZIP
309: while (err != Z_STREAM_END) {
310: #else /* !FUNZIP */
311: while (G.csize > 0) {
312: Trace((stderr, "first loop: G.csize = %ld\n", G.csize));
313: #endif /* ?FUNZIP */
314: while (G.dstrm.avail_out > 0) {
315: err = inflate(&G.dstrm, Z_PARTIAL_FLUSH);
316:
317: if (err == Z_DATA_ERROR)
318: return 2;
319: else if (err == Z_MEM_ERROR)
320: return 3;
321: else if (err != Z_OK && err != Z_STREAM_END)
322: Trace((stderr, "oops! (inflate(first loop) err = %d)\n", err));
323:
324: #ifdef FUNZIP
325: if (err == Z_STREAM_END) /* "END-of-entry-condition" ? */
326: #else /* !FUNZIP */
327: if (G.csize <= 0L) /* "END-of-entry-condition" ? */
328: #endif /* ?FUNZIP */
329: break;
330:
331: if (G.dstrm.avail_in <= 0) {
332: if (fillinbuf(__G) == 0)
333: return 2; /* no "END-condition" yet, but no more data */
334:
335: G.dstrm.next_in = G.inptr;
336: G.dstrm.avail_in = G.incnt;
337: }
338: Trace((stderr, " avail_in = %d\n", G.dstrm.avail_in));
339: }
340: FLUSH(wsize - G.dstrm.avail_out); /* flush slide[] */
341: Trace((stderr, "inside loop: flushing %ld bytes (ptr diff = %ld)\n",
342: (long)(wsize - G.dstrm.avail_out),
343: (long)(G.dstrm.next_out-(Bytef *)redirSlide)));
344: G.dstrm.next_out = redirSlide;
345: G.dstrm.avail_out = wsize;
346: }
347:
348: /* no more input, so loop until we have all output */
349: Trace((stderr, "beginning final loop: err = %d\n", err));
350: while (err != Z_STREAM_END) {
351: err = inflate(&G.dstrm, Z_PARTIAL_FLUSH);
352: if (err == Z_DATA_ERROR)
353: return 2;
354: else if (err == Z_MEM_ERROR)
355: return 3;
356: else if (err == Z_BUF_ERROR) { /* DEBUG */
357: Trace((stderr, "zlib inflate() did not detect stream end (%s, %s)\n"
358: , G.zipfn, G.filename));
359: break;
360: } else if (err != Z_OK && err != Z_STREAM_END) {
361: Trace((stderr, "oops! (inflate(final loop) err = %d)\n", err));
362: DESTROYGLOBALS()
363: EXIT(PK_MEM3);
364: }
365: FLUSH(wsize - G.dstrm.avail_out); /* final flush of slide[] */
366: Trace((stderr, "final loop: flushing %ld bytes (ptr diff = %ld)\n",
367: (long)(wsize - G.dstrm.avail_out),
368: (long)(G.dstrm.next_out-(Bytef *)redirSlide)));
369: G.dstrm.next_out = redirSlide;
370: G.dstrm.avail_out = wsize;
371: }
372: Trace((stderr, "total in = %ld, total out = %ld\n", G.dstrm.total_in,
373: G.dstrm.total_out));
374:
375: G.inptr = (uch *)G.dstrm.next_in;
376: G.incnt = (G.inbuf + INBUFSIZ) - G.inptr; /* reset for other routines */
377:
378: err = inflateReset(&G.dstrm);
379: if (err != Z_OK)
380: Trace((stderr, "oops! (inflateReset() err = %d)\n", err));
381:
382: return 0;
383: }
384:
385:
386: /*---------------------------------------------------------------------------*/
387: #else /* !USE_ZLIB */
388:
389:
390: /* Function prototypes */
391: #ifndef OF
392: # ifdef __STDC__
393: # define OF(a) a
394: # else
395: # define OF(a) ()
396: # endif
397: #endif /* !OF */
398: int inflate_codes OF((__GPRO__ struct huft *tl, struct huft *td,
399: int bl, int bd));
400: static int inflate_stored OF((__GPRO));
401: static int inflate_fixed OF((__GPRO));
402: static int inflate_dynamic OF((__GPRO));
403: static int inflate_block OF((__GPRO__ int *e));
404:
405:
406: /* The inflate algorithm uses a sliding 32K byte window on the uncompressed
407: stream to find repeated byte strings. This is implemented here as a
408: circular buffer. The index is updated simply by incrementing and then
409: and'ing with 0x7fff (32K-1). */
410: /* It is left to other modules to supply the 32K area. It is assumed
411: to be usable as if it were declared "uch slide[32768];" or as just
412: "uch *slide;" and then malloc'ed in the latter case. The definition
413: must be in unzip.h, included above. */
414:
415:
416: /* unsigned wp; moved to globals.h */ /* current position in slide */
417:
418:
419: /* Tables for deflate from PKZIP's appnote.txt. */
420: static ZCONST unsigned border[] = { /* Order of the bit length code lengths */
421: 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
422: static ZCONST ush cplens[] = { /* Copy lengths for literal codes 257..285 */
423: 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
424: 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
425: /* note: see note #13 above about the 258 in this list. */
426: static ZCONST ush cplext[] = { /* Extra bits for literal codes 257..285 */
427: 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
428: 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 99, 99}; /* 99==invalid */
429: static ZCONST ush cpdist[] = { /* Copy offsets for distance codes 0..29 */
430: 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
431: 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
432: 8193, 12289, 16385, 24577};
433: static ZCONST ush cpdext[] = { /* Extra bits for distance codes */
434: 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
435: 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
436: 12, 12, 13, 13};
437:
438:
439: /* moved to consts.h (included in unzip.c), resp. funzip.c */
440: #if 1
441: /* And'ing with mask_bits[n] masks the lower n bits */
442: ZCONST ush near mask_bits[] = {
443: 0x0000,
444: 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
445: 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
446: };
447: #endif /* 0 */
448:
449:
450: /* Macros for inflate() bit peeking and grabbing.
451: The usage is:
452:
453: NEEDBITS(j)
454: x = b & mask_bits[j];
455: DUMPBITS(j)
456:
457: where NEEDBITS makes sure that b has at least j bits in it, and
458: DUMPBITS removes the bits from b. The macros use the variable k
459: for the number of bits in b. Normally, b and k are register
460: variables for speed and are initialized at the begining of a
461: routine that uses these macros from a global bit buffer and count.
462:
463: In order to not ask for more bits than there are in the compressed
464: stream, the Huffman tables are constructed to only ask for just
465: enough bits to make up the end-of-block code (value 256). Then no
466: bytes need to be "returned" to the buffer at the end of the last
467: block. See the huft_build() routine.
468: */
469:
470: /* These have been moved to globals.h */
471: #if 0
472: ulg bb; /* bit buffer */
473: unsigned bk; /* bits in bit buffer */
474: #endif
475:
476: #ifndef CHECK_EOF
477: # define CHECK_EOF /* default as of 5.13/5.2 */
478: #endif
479:
480: #ifndef CHECK_EOF
481: # define NEEDBITS(n) {while(k<(n)){b|=((ulg)NEXTBYTE)<<k;k+=8;}}
482: #else
483: # define NEEDBITS(n) {while(k<(n)){int c=NEXTBYTE;if(c==EOF)return 1;\
484: b|=((ulg)c)<<k;k+=8;}}
485: #endif /* Piet Plomp: change "return 1" to "break" */
486:
487: #define DUMPBITS(n) {b>>=(n);k-=(n);}
488:
489:
490: /*
491: Huffman code decoding is performed using a multi-level table lookup.
492: The fastest way to decode is to simply build a lookup table whose
493: size is determined by the longest code. However, the time it takes
494: to build this table can also be a factor if the data being decoded
495: are not very long. The most common codes are necessarily the
496: shortest codes, so those codes dominate the decoding time, and hence
497: the speed. The idea is you can have a shorter table that decodes the
498: shorter, more probable codes, and then point to subsidiary tables for
499: the longer codes. The time it costs to decode the longer codes is
500: then traded against the time it takes to make longer tables.
501:
502: This results of this trade are in the variables lbits and dbits
503: below. lbits is the number of bits the first level table for literal/
504: length codes can decode in one step, and dbits is the same thing for
505: the distance codes. Subsequent tables are also less than or equal to
506: those sizes. These values may be adjusted either when all of the
507: codes are shorter than that, in which case the longest code length in
508: bits is used, or when the shortest code is *longer* than the requested
509: table size, in which case the length of the shortest code in bits is
510: used.
511:
512: There are two different values for the two tables, since they code a
513: different number of possibilities each. The literal/length table
514: codes 286 possible values, or in a flat code, a little over eight
515: bits. The distance table codes 30 possible values, or a little less
516: than five bits, flat. The optimum values for speed end up being
517: about one bit more than those, so lbits is 8+1 and dbits is 5+1.
518: The optimum values may differ though from machine to machine, and
519: possibly even between compilers. Your mileage may vary.
520: */
521:
522: static ZCONST int lbits = 9; /* bits in base literal/length lookup table */
523: static ZCONST int dbits = 6; /* bits in base distance lookup table */
524:
525:
526: #ifndef ASM_INFLATECODES
527:
528: int inflate_codes(__G__ tl, td, bl, bd)
529: __GDEF
530: struct huft *tl, *td; /* literal/length and distance decoder tables */
531: int bl, bd; /* number of bits decoded by tl[] and td[] */
532: /* inflate (decompress) the codes in a deflated (compressed) block.
533: Return an error code or zero if it all goes ok. */
534: {
535: register unsigned e; /* table entry flag/number of extra bits */
536: unsigned n, d; /* length and index for copy */
537: unsigned w; /* current window position */
538: struct huft *t; /* pointer to table entry */
539: unsigned ml, md; /* masks for bl and bd bits */
540: register ulg b; /* bit buffer */
541: register unsigned k; /* number of bits in bit buffer */
542:
543:
544: /* make local copies of globals */
545: b = G.bb; /* initialize bit buffer */
546: k = G.bk;
547: w = G.wp; /* initialize window position */
548:
549:
550: /* inflate the coded data */
551: ml = mask_bits[bl]; /* precompute masks for speed */
552: md = mask_bits[bd];
553: while (1) /* do until end of block */
554: {
555: NEEDBITS((unsigned)bl)
556: if ((e = (t = tl + ((unsigned)b & ml))->e) > 16)
557: do {
558: if (e == 99)
559: return 1;
560: DUMPBITS(t->b)
561: e -= 16;
562: NEEDBITS(e)
563: } while ((e = (t = t->v.t + ((unsigned)b & mask_bits[e]))->e) > 16);
564: DUMPBITS(t->b)
565: if (e == 16) /* then it's a literal */
566: {
567: redirSlide[w++] = (uch)t->v.n;
568: if (w == wsize)
569: {
570: FLUSH(w);
571: w = 0;
572: }
573: }
574: else /* it's an EOB or a length */
575: {
576: /* exit if end of block */
577: if (e == 15)
578: break;
579:
580: /* get length of block to copy */
581: NEEDBITS(e)
582: n = t->v.n + ((unsigned)b & mask_bits[e]);
583: DUMPBITS(e);
584:
585: /* decode distance of block to copy */
586: NEEDBITS((unsigned)bd)
587: if ((e = (t = td + ((unsigned)b & md))->e) > 16)
588: do {
589: if (e == 99)
590: return 1;
591: DUMPBITS(t->b)
592: e -= 16;
593: NEEDBITS(e)
594: } while ((e = (t = t->v.t + ((unsigned)b & mask_bits[e]))->e) > 16);
595: DUMPBITS(t->b)
596: NEEDBITS(e)
597: d = w - t->v.n - ((unsigned)b & mask_bits[e]);
598: DUMPBITS(e)
599:
600: /* do the copy */
601: do {
602: #if (defined(DLL) && !defined(NO_SLIDE_REDIR))
603: if (G.redirect_slide) {/* &= w/ wsize unnecessary & wrong if redirect */
604: if (d >= wsize)
605: return 1; /* invalid compressed data */
606: n -= (e = (e = wsize - (d > w ? d : w)) > n ? n : e);
607: }
608: else
609: #endif
610: n -= (e = (e = wsize - ((d &= wsize-1) > w ? d : w)) > n ? n : e);
611: #ifndef NOMEMCPY
612: if (w - d >= e) /* (this test assumes unsigned comparison) */
613: {
614: memcpy(redirSlide + w, redirSlide + d, e);
615: w += e;
616: d += e;
617: }
618: else /* do it slowly to avoid memcpy() overlap */
619: #endif /* !NOMEMCPY */
620: do {
621: redirSlide[w++] = redirSlide[d++];
622: } while (--e);
623: if (w == wsize)
624: {
625: FLUSH(w);
626: w = 0;
627: }
628: } while (n);
629: }
630: }
631:
632:
633: /* restore the globals from the locals */
634: G.wp = w; /* restore global window pointer */
635: G.bb = b; /* restore global bit buffer */
636: G.bk = k;
637:
638:
639: /* done */
640: return 0;
641: }
642:
643: #endif /* ASM_INFLATECODES */
644:
645:
646:
647: static int inflate_stored(__G)
648: __GDEF
649: /* "decompress" an inflated type 0 (stored) block. */
650: {
651: unsigned n; /* number of bytes in block */
652: unsigned w; /* current window position */
653: register ulg b; /* bit buffer */
654: register unsigned k; /* number of bits in bit buffer */
655:
656:
657: /* make local copies of globals */
658: Trace((stderr, "\nstored block"));
659: b = G.bb; /* initialize bit buffer */
660: k = G.bk;
661: w = G.wp; /* initialize window position */
662:
663:
664: /* go to byte boundary */
665: n = k & 7;
666: DUMPBITS(n);
667:
668:
669: /* get the length and its complement */
670: NEEDBITS(16)
671: n = ((unsigned)b & 0xffff);
672: DUMPBITS(16)
673: NEEDBITS(16)
674: if (n != (unsigned)((~b) & 0xffff))
675: return 1; /* error in compressed data */
676: DUMPBITS(16)
677:
678:
679: /* read and output the compressed data */
680: while (n--)
681: {
682: NEEDBITS(8)
683: redirSlide[w++] = (uch)b;
684: if (w == wsize)
685: {
686: FLUSH(w);
687: w = 0;
688: }
689: DUMPBITS(8)
690: }
691:
692:
693: /* restore the globals from the locals */
694: G.wp = w; /* restore global window pointer */
695: G.bb = b; /* restore global bit buffer */
696: G.bk = k;
697: return 0;
698: }
699:
700:
701: /* Globals for literal tables (built once) */
702: /* Moved to globals.h */
703: #if 0
704: struct huft *fixed_tl = (struct huft *)NULL;
705: struct huft *fixed_td;
706: int fixed_bl, fixed_bd;
707: #endif
708:
709: static int inflate_fixed(__G)
710: __GDEF
711: /* decompress an inflated type 1 (fixed Huffman codes) block. We should
712: either replace this with a custom decoder, or at least precompute the
713: Huffman tables. */
714: {
715: /* if first time, set up tables for fixed blocks */
716: Trace((stderr, "\nliteral block"));
717: if (G.fixed_tl == (struct huft *)NULL)
718: {
719: int i; /* temporary variable */
720: unsigned l[288]; /* length list for huft_build */
721:
722: /* literal table */
723: for (i = 0; i < 144; i++)
724: l[i] = 8;
725: for (; i < 256; i++)
726: l[i] = 9;
727: for (; i < 280; i++)
728: l[i] = 7;
729: for (; i < 288; i++) /* make a complete, but wrong code set */
730: l[i] = 8;
731: G.fixed_bl = 7;
732: if ((i = huft_build(__G__ l, 288, 257, cplens, cplext,
733: &G.fixed_tl, &G.fixed_bl)) != 0)
734: {
735: G.fixed_tl = (struct huft *)NULL;
736: return i;
737: }
738:
739: /* distance table */
740: for (i = 0; i < 30; i++) /* make an incomplete code set */
741: l[i] = 5;
742: G.fixed_bd = 5;
743: if ((i = huft_build(__G__ l, 30, 0, cpdist, cpdext,
744: &G.fixed_td, &G.fixed_bd)) > 1)
745: {
746: huft_free(G.fixed_tl);
747: G.fixed_tl = (struct huft *)NULL;
748: return i;
749: }
750: }
751:
752: /* decompress until an end-of-block code */
753: return inflate_codes(__G__ G.fixed_tl, G.fixed_td,
754: G.fixed_bl, G.fixed_bd) != 0;
755: }
756:
757:
758:
759: static int inflate_dynamic(__G)
760: __GDEF
761: /* decompress an inflated type 2 (dynamic Huffman codes) block. */
762: {
763: int i; /* temporary variables */
764: unsigned j;
765: unsigned l; /* last length */
766: unsigned m; /* mask for bit lengths table */
767: unsigned n; /* number of lengths to get */
768: struct huft *tl; /* literal/length code table */
769: struct huft *td; /* distance code table */
770: int bl; /* lookup bits for tl */
771: int bd; /* lookup bits for td */
772: unsigned nb; /* number of bit length codes */
773: unsigned nl; /* number of literal/length codes */
774: unsigned nd; /* number of distance codes */
775: #ifdef PKZIP_BUG_WORKAROUND
776: unsigned ll[288+32]; /* literal/length and distance code lengths */
777: #else
778: unsigned ll[286+30]; /* literal/length and distance code lengths */
779: #endif
780: register ulg b; /* bit buffer */
781: register unsigned k; /* number of bits in bit buffer */
782:
783:
784: /* make local bit buffer */
785: Trace((stderr, "\ndynamic block"));
786: b = G.bb;
787: k = G.bk;
788:
789:
790: /* read in table lengths */
791: NEEDBITS(5)
792: nl = 257 + ((unsigned)b & 0x1f); /* number of literal/length codes */
793: DUMPBITS(5)
794: NEEDBITS(5)
795: nd = 1 + ((unsigned)b & 0x1f); /* number of distance codes */
796: DUMPBITS(5)
797: NEEDBITS(4)
798: nb = 4 + ((unsigned)b & 0xf); /* number of bit length codes */
799: DUMPBITS(4)
800: #ifdef PKZIP_BUG_WORKAROUND
801: if (nl > 288 || nd > 32)
802: #else
803: if (nl > 286 || nd > 30)
804: #endif
805: return 1; /* bad lengths */
806:
807:
808: /* read in bit-length-code lengths */
809: for (j = 0; j < nb; j++)
810: {
811: NEEDBITS(3)
812: ll[border[j]] = (unsigned)b & 7;
813: DUMPBITS(3)
814: }
815: for (; j < 19; j++)
816: ll[border[j]] = 0;
817:
818:
819: /* build decoding table for trees--single level, 7 bit lookup */
820: bl = 7;
821: i = huft_build(__G__ ll, 19, 19, NULL, NULL, &tl, &bl);
822: if (bl == 0) /* no bit lengths */
823: i = 1;
824: if (i)
825: {
826: if (i == 1)
827: huft_free(tl);
828: return i; /* incomplete code set */
829: }
830:
831:
832: /* read in literal and distance code lengths */
833: n = nl + nd;
834: m = mask_bits[bl];
835: i = l = 0;
836: while ((unsigned)i < n)
837: {
838: NEEDBITS((unsigned)bl)
839: j = (td = tl + ((unsigned)b & m))->b;
840: DUMPBITS(j)
841: j = td->v.n;
842: if (j < 16) /* length of code in bits (0..15) */
843: ll[i++] = l = j; /* save last length in l */
844: else if (j == 16) /* repeat last length 3 to 6 times */
845: {
846: NEEDBITS(2)
847: j = 3 + ((unsigned)b & 3);
848: DUMPBITS(2)
849: if ((unsigned)i + j > n)
850: return 1;
851: while (j--)
852: ll[i++] = l;
853: }
854: else if (j == 17) /* 3 to 10 zero length codes */
855: {
856: NEEDBITS(3)
857: j = 3 + ((unsigned)b & 7);
858: DUMPBITS(3)
859: if ((unsigned)i + j > n)
860: return 1;
861: while (j--)
862: ll[i++] = 0;
863: l = 0;
864: }
865: else /* j == 18: 11 to 138 zero length codes */
866: {
867: NEEDBITS(7)
868: j = 11 + ((unsigned)b & 0x7f);
869: DUMPBITS(7)
870: if ((unsigned)i + j > n)
871: return 1;
872: while (j--)
873: ll[i++] = 0;
874: l = 0;
875: }
876: }
877:
878:
879: /* free decoding table for trees */
880: huft_free(tl);
881:
882:
883: /* restore the global bit buffer */
884: G.bb = b;
885: G.bk = k;
886:
887:
888: /* build the decoding tables for literal/length and distance codes */
889: bl = lbits;
890: i = huft_build(__G__ ll, nl, 257, cplens, cplext, &tl, &bl);
891: if (bl == 0) /* no literals or lengths */
892: i = 1;
893: if (i)
894: {
895: if (i == 1) {
896: //if (!uO.qflag)
897: MESSAGE((uch *)"(incomplete l-tree) ", 21L, 1);
898: huft_free(tl);
899: }
900: return i; /* incomplete code set */
901: }
902: bd = dbits;
903: i = huft_build(__G__ ll + nl, nd, 0, cpdist, cpdext, &td, &bd);
904: if (bd == 0 && nl > 257) /* lengths but no distances */
905: {
906: //if (!uO.qflag)
907: MESSAGE((uch *)"(incomplete d-tree) ", 21L, 1);
908: huft_free(tl);
909: return 1;
910: }
911: if (i == 1) {
912: #ifdef PKZIP_BUG_WORKAROUND
913: i = 0;
914: #else
915: //if (!uO.qflag)
916: MESSAGE((uch *)"(incomplete d-tree) ", 21L, 1);
917: huft_free(td);
918: #endif
919: }
920: if (i)
921: {
922: huft_free(tl);
923: return i;
924: }
925:
926:
927: /* decompress until an end-of-block code */
928: if (inflate_codes(__G__ tl, td, bl, bd))
929: return 1;
930:
931:
932: /* free the decoding tables, return */
933: huft_free(tl);
934: huft_free(td);
935: return 0;
936: }
937:
938:
939:
940: static int inflate_block(__G__ e)
941: __GDEF
942: int *e; /* last block flag */
943: /* decompress an inflated block */
944: {
945: unsigned t; /* block type */
946: register ulg b; /* bit buffer */
947: register unsigned k; /* number of bits in bit buffer */
948:
949:
950: /* make local bit buffer */
951: b = G.bb;
952: k = G.bk;
953:
954:
955: /* read in last block bit */
956: NEEDBITS(1)
957: *e = (int)b & 1;
958: DUMPBITS(1)
959:
960:
961: /* read in block type */
962: NEEDBITS(2)
963: t = (unsigned)b & 3;
964: DUMPBITS(2)
965:
966:
967: /* restore the global bit buffer */
968: G.bb = b;
969: G.bk = k;
970:
971:
972: /* inflate that block type */
973: if (t == 2)
974: return inflate_dynamic(__G);
975: if (t == 0)
976: return inflate_stored(__G);
977: if (t == 1)
978: return inflate_fixed(__G);
979:
980:
981: /* bad block type */
982: return 2;
983: }
984:
985:
986:
987: int inflate(__G)
988: __GDEF
989: /* decompress an inflated entry */
990: {
991: int e; /* last block flag */
992: int r; /* result code */
993: #ifdef DEBUG
994: unsigned h = 0; /* maximum struct huft's malloc'ed */
995: #endif
996:
997: #if (defined(DLL) && !defined(NO_SLIDE_REDIR))
998: if (G.redirect_slide)
999: wsize = G.redirect_size, redirSlide = G.redirect_buffer;
1000: else
1001: wsize = WSIZE, redirSlide = slide; /* how they're #defined if !DLL */
1002: #endif
1003:
1004: /* initialize window, bit buffer */
1005: G.wp = 0;
1006: G.bk = 0;
1007: G.bb = 0;
1008:
1009:
1010: /* decompress until the last block */
1011: do {
1012: #ifdef DEBUG
1013: G.hufts = 0;
1014: #endif
1015: if ((r = inflate_block(__G__ &e)) != 0)
1016: return r;
1017: #ifdef DEBUG
1018: if (G.hufts > h)
1019: h = G.hufts;
1020: #endif
1021: } while (!e);
1022:
1023:
1024: /* flush out redirSlide */
1025: FLUSH(G.wp);
1026:
1027:
1028: /* return success */
1029: Trace((stderr, "\n%u bytes in Huffman tables (%d/entry)\n",
1030: h * sizeof(struct huft), sizeof(struct huft)));
1031: return 0;
1032: }
1033:
1034:
1035:
1036: int inflate_free(__G)
1037: __GDEF
1038: {
1039: if (G.fixed_tl != (struct huft *)NULL)
1040: {
1041: huft_free(G.fixed_td);
1042: huft_free(G.fixed_tl);
1043: G.fixed_td = G.fixed_tl = (struct huft *)NULL;
1044: }
1045: return 0;
1046: }
1047:
1048: #endif /* ?USE_ZLIB */
1049:
1050:
1051: /*
1052: * GRR: moved huft_build() and huft_free() down here; used by explode()
1053: * and fUnZip regardless of whether USE_ZLIB defined or not
1054: */
1055:
1056:
1057: /* If BMAX needs to be larger than 16, then h and x[] should be ulg. */
1058: #define BMAX 16 /* maximum bit length of any code (16 for explode) */
1059: #define N_MAX 288 /* maximum number of codes in any set */
1060:
1061:
1062: int huft_build(
1063: __GDEF
1064: ZCONST unsigned *b, /* code lengths in bits (all assumed <= BMAX) */
1065: unsigned n, /* number of codes (assumed <= N_MAX) */
1066: unsigned s, /* number of simple-valued codes (0..s-1) */
1067: ZCONST ush *d, /* list of base values for non-simple codes */
1068: ZCONST ush *e, /* list of extra bits for non-simple codes */
1069: struct huft **t, /* result: starting table */
1070: int *m /* maximum lookup bits, returns actual */
1071: )
1072: /* Given a list of code lengths and a maximum table size, make a set of
1073: tables to decode that set of codes. Return zero on success, one if
1074: the given code set is incomplete (the tables are still built in this
1075: case), two if the input is invalid (all zero length codes or an
1076: oversubscribed set of lengths), and three if not enough memory.
1077: The code with value 256 is special, and the tables are constructed
1078: so that no bits beyond that code are fetched when that code is
1079: decoded. */
1080: {
1081: unsigned a; /* counter for codes of length k */
1082: unsigned c[BMAX+1]; /* bit length count table */
1083: unsigned el; /* length of EOB code (value 256) */
1084: unsigned f; /* i repeats in table every f entries */
1085: int g; /* maximum code length */
1086: int h; /* table level */
1087: register unsigned i; /* counter, current code */
1088: register unsigned j; /* counter */
1089: register int k; /* number of bits in current code */
1090: int lx[BMAX+1]; /* memory for l[-1..BMAX-1] */
1091: int *l = lx+1; /* stack of bits per table */
1092: register unsigned *p; /* pointer into c[], b[], or v[] */
1093: register struct huft *q; /* points to current table */
1094: struct huft r; /* table entry for structure assignment */
1095: struct huft *u[BMAX]; /* table stack */
1096: unsigned v[N_MAX]; /* values in order of bit length */
1097: register int w; /* bits before this table == (l * h) */
1098: unsigned x[BMAX+1]; /* bit offsets, then code stack */
1099: unsigned *xp; /* pointer into x */
1100: int y; /* number of dummy codes added */
1101: unsigned z; /* number of entries in current table */
1102:
1103:
1104: /* Generate counts for each bit length */
1105: el = n > 256 ? b[256] : BMAX; /* set length of EOB code, if any */
1106: memset(c, 0, sizeof(c));
1107: p = (unsigned *)b; i = n;
1108: do {
1109: c[*p]++; p++; /* assume all entries <= BMAX */
1110: } while (--i);
1111: if (c[0] == n) /* null input--all zero length codes */
1112: {
1113: *t = (struct huft *)NULL;
1114: *m = 0;
1115: return 0;
1116: }
1117:
1118:
1119: /* Find minimum and maximum length, bound *m by those */
1120: for (j = 1; j <= BMAX; j++)
1121: if (c[j])
1122: break;
1123: k = j; /* minimum code length */
1124: if ((unsigned)*m < j)
1125: *m = j;
1126: for (i = BMAX; i; i--)
1127: if (c[i])
1128: break;
1129: g = i; /* maximum code length */
1130: if ((unsigned)*m > i)
1131: *m = i;
1132:
1133:
1134: /* Adjust last length count to fill out codes, if needed */
1135: for (y = 1 << j; j < i; j++, y <<= 1)
1136: if ((y -= c[j]) < 0)
1137: return 2; /* bad input: more codes than bits */
1138: if ((y -= c[i]) < 0)
1139: return 2;
1140: c[i] += y;
1141:
1142:
1143: /* Generate starting offsets into the value table for each length */
1144: x[1] = j = 0;
1145: p = c + 1; xp = x + 2;
1146: while (--i) { /* note that i == g from above */
1147: *xp++ = (j += *p++);
1148: }
1149:
1150:
1151: /* Make a table of values in order of bit lengths */
1152: memset(v, 0, sizeof(v));
1153: p = (unsigned *)b; i = 0;
1154: do {
1155: if ((j = *p++) != 0)
1156: v[x[j]++] = i;
1157: } while (++i < n);
1158: n = x[g]; /* set n to length of v */
1159:
1160:
1161: /* Generate the Huffman codes and for each, make the table entries */
1162: x[0] = i = 0; /* first Huffman code is zero */
1163: p = v; /* grab values in bit order */
1164: h = -1; /* no tables yet--level -1 */
1165: w = l[-1] = 0; /* no bits decoded yet */
1166: u[0] = (struct huft *)NULL; /* just to keep compilers happy */
1167: q = (struct huft *)NULL; /* ditto */
1168: z = 0; /* ditto */
1169:
1170: /* go through the bit lengths (k already is bits in shortest code) */
1171: for (; k <= g; k++)
1172: {
1173: a = c[k];
1174: while (a--)
1175: {
1176: /* here i is the Huffman code of length k bits for value *p */
1177: /* make tables up to required level */
1178: while (k > w + l[h])
1179: {
1180: w += l[h++]; /* add bits already decoded */
1181:
1182: /* compute minimum size table less than or equal to *m bits */
1183: z = (z = g - w) > (unsigned)*m ? *m : z; /* upper limit */
1184: if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */
1185: { /* too few codes for k-w bit table */
1186: f -= a + 1; /* deduct codes from patterns left */
1187: xp = c + k;
1188: while (++j < z) /* try smaller tables up to z bits */
1189: {
1190: if ((f <<= 1) <= *++xp)
1191: break; /* enough codes to use up j bits */
1192: f -= *xp; /* else deduct codes from patterns */
1193: }
1194: }
1195: if ((unsigned)w + j > el && (unsigned)w < el)
1196: j = el - w; /* make EOB code end at table */
1197: z = 1 << j; /* table entries for j-bit table */
1198: l[h] = j; /* set table size in stack */
1199:
1200: /* allocate and link in new table */
1201: if ((q = (struct huft *)malloc((z + 1)*sizeof(struct huft))) ==
1202: (struct huft *)NULL)
1203: {
1204: if (h)
1205: huft_free(u[0]);
1206: return 3; /* not enough memory */
1207: }
1208: #ifdef DEBUG
1209: G.hufts += z + 1; /* track memory usage */
1210: #endif
1211: *t = q + 1; /* link to list for huft_free() */
1212: *(t = &(q->v.t)) = (struct huft *)NULL;
1213: u[h] = ++q; /* table starts after link */
1214:
1215: /* connect to last table, if there is one */
1216: if (h)
1217: {
1218: x[h] = i; /* save pattern for backing up */
1219: r.b = (uch)l[h-1]; /* bits to dump before this table */
1220: r.e = (uch)(16 + j); /* bits in this table */
1221: r.v.t = q; /* pointer to this table */
1222: j = (i & ((1 << w) - 1)) >> (w - l[h-1]);
1223: u[h-1][j] = r; /* connect to last table */
1224: }
1225: }
1226:
1227: /* set up table entry in r */
1228: r.b = (uch)(k - w);
1229: if (p >= v + n)
1230: r.e = 99; /* out of values--invalid code */
1231: else if (*p < s)
1232: {
1233: r.e = (uch)(*p < 256 ? 16 : 15); /* 256 is end-of-block code */
1234: r.v.n = (ush)*p++; /* simple code is just the value */
1235: }
1236: else
1237: {
1238: r.e = (uch)e[*p - s]; /* non-simple--look up in lists */
1239: r.v.n = d[*p++ - s];
1240: }
1241:
1242: /* fill code-like entries with r */
1243: f = 1 << (k - w);
1244: for (j = i >> w; j < z; j += f)
1245: q[j] = r;
1246:
1247: /* backwards increment the k-bit code i */
1248: for (j = 1 << (k - 1); i & j; j >>= 1)
1249: i ^= j;
1250: i ^= j;
1251:
1252: /* backup over finished tables */
1253: while ((i & ((1 << w) - 1)) != x[h])
1254: w -= l[--h]; /* don't need to update q */
1255: }
1256: }
1257:
1258:
1259: /* return actual size of base table */
1260: *m = l[0];
1261:
1262:
1263: /* Return true (1) if we were given an incomplete table */
1264: return y != 0 && g != 1;
1265: }
1266:
1267:
1268:
1269: int huft_free (struct huft *t)
1270: /* table to free */
1271: /* Free the malloc'ed tables built by huft_build(), which makes a linked
1272: list of the tables it made, with the links in a dummy first entry of
1273: each table. */
1274: {
1275: register struct huft *p, *q;
1276:
1277:
1278: /* Go through linked list, freeing from the malloced (t[-1]) address. */
1279: p = t;
1280: while (p != (struct huft *)NULL)
1281: {
1282: q = (--p)->v.t;
1283: free((zvoid *)p);
1284: p = q;
1285: }
1286: return 0;
1287: }
1288:
1289:
1290: // Main public function. Decompresses raw data compressed using the DEFLATE algorithm (RFC 1951 - e.g. zlib, gzip).
1291: // Returns 0 if decompression fails or, if successful, returns the size of the decompressed data.
1292: int DecompressDeflatedData (char *out, char *in, int inLength)
1293: {
1294: G.outbufptr = out;
1295: G.inptr = in;
1296: G.incnt = inLength;
1297: G.outCounter = 0;
1298:
1299: if (inflate(__G) != 0)
1300: {
1301: // Error decompressing
1302: return 0;
1303: }
1304: return G.outCounter;
1305: }
1306:
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