Contents of /alx-src/tags/kernel26-2.6.12-alx-r9/lib/inflate.c
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Wed Mar 4 11:03:09 2009 UTC (15 years, 6 months ago) by niro
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Tag kernel26-2.6.12-alx-r9
1 | #define DEBG(x) |
2 | #define DEBG1(x) |
3 | /* inflate.c -- Not copyrighted 1992 by Mark Adler |
4 | version c10p1, 10 January 1993 */ |
5 | |
6 | /* |
7 | * Adapted for booting Linux by Hannu Savolainen 1993 |
8 | * based on gzip-1.0.3 |
9 | * |
10 | * Nicolas Pitre <nico@cam.org>, 1999/04/14 : |
11 | * Little mods for all variable to reside either into rodata or bss segments |
12 | * by marking constant variables with 'const' and initializing all the others |
13 | * at run-time only. This allows for the kernel uncompressor to run |
14 | * directly from Flash or ROM memory on embedded systems. |
15 | */ |
16 | |
17 | /* |
18 | Inflate deflated (PKZIP's method 8 compressed) data. The compression |
19 | method searches for as much of the current string of bytes (up to a |
20 | length of 258) in the previous 32 K bytes. If it doesn't find any |
21 | matches (of at least length 3), it codes the next byte. Otherwise, it |
22 | codes the length of the matched string and its distance backwards from |
23 | the current position. There is a single Huffman code that codes both |
24 | single bytes (called "literals") and match lengths. A second Huffman |
25 | code codes the distance information, which follows a length code. Each |
26 | length or distance code actually represents a base value and a number |
27 | of "extra" (sometimes zero) bits to get to add to the base value. At |
28 | the end of each deflated block is a special end-of-block (EOB) literal/ |
29 | length code. The decoding process is basically: get a literal/length |
30 | code; if EOB then done; if a literal, emit the decoded byte; if a |
31 | length then get the distance and emit the referred-to bytes from the |
32 | sliding window of previously emitted data. |
33 | |
34 | There are (currently) three kinds of inflate blocks: stored, fixed, and |
35 | dynamic. The compressor deals with some chunk of data at a time, and |
36 | decides which method to use on a chunk-by-chunk basis. A chunk might |
37 | typically be 32 K or 64 K. If the chunk is incompressible, then the |
38 | "stored" method is used. In this case, the bytes are simply stored as |
39 | is, eight bits per byte, with none of the above coding. The bytes are |
40 | preceded by a count, since there is no longer an EOB code. |
41 | |
42 | If the data is compressible, then either the fixed or dynamic methods |
43 | are used. In the dynamic method, the compressed data is preceded by |
44 | an encoding of the literal/length and distance Huffman codes that are |
45 | to be used to decode this block. The representation is itself Huffman |
46 | coded, and so is preceded by a description of that code. These code |
47 | descriptions take up a little space, and so for small blocks, there is |
48 | a predefined set of codes, called the fixed codes. The fixed method is |
49 | used if the block codes up smaller that way (usually for quite small |
50 | chunks), otherwise the dynamic method is used. In the latter case, the |
51 | codes are customized to the probabilities in the current block, and so |
52 | can code it much better than the pre-determined fixed codes. |
53 | |
54 | The Huffman codes themselves are decoded using a multi-level table |
55 | lookup, in order to maximize the speed of decoding plus the speed of |
56 | building the decoding tables. See the comments below that precede the |
57 | lbits and dbits tuning parameters. |
58 | */ |
59 | |
60 | |
61 | /* |
62 | Notes beyond the 1.93a appnote.txt: |
63 | |
64 | 1. Distance pointers never point before the beginning of the output |
65 | stream. |
66 | 2. Distance pointers can point back across blocks, up to 32k away. |
67 | 3. There is an implied maximum of 7 bits for the bit length table and |
68 | 15 bits for the actual data. |
69 | 4. If only one code exists, then it is encoded using one bit. (Zero |
70 | would be more efficient, but perhaps a little confusing.) If two |
71 | codes exist, they are coded using one bit each (0 and 1). |
72 | 5. There is no way of sending zero distance codes--a dummy must be |
73 | sent if there are none. (History: a pre 2.0 version of PKZIP would |
74 | store blocks with no distance codes, but this was discovered to be |
75 | too harsh a criterion.) Valid only for 1.93a. 2.04c does allow |
76 | zero distance codes, which is sent as one code of zero bits in |
77 | length. |
78 | 6. There are up to 286 literal/length codes. Code 256 represents the |
79 | end-of-block. Note however that the static length tree defines |
80 | 288 codes just to fill out the Huffman codes. Codes 286 and 287 |
81 | cannot be used though, since there is no length base or extra bits |
82 | defined for them. Similarly, there are up to 30 distance codes. |
83 | However, static trees define 32 codes (all 5 bits) to fill out the |
84 | Huffman codes, but the last two had better not show up in the data. |
85 | 7. Unzip can check dynamic Huffman blocks for complete code sets. |
86 | The exception is that a single code would not be complete (see #4). |
87 | 8. The five bits following the block type is really the number of |
88 | literal codes sent minus 257. |
89 | 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits |
90 | (1+6+6). Therefore, to output three times the length, you output |
91 | three codes (1+1+1), whereas to output four times the same length, |
92 | you only need two codes (1+3). Hmm. |
93 | 10. In the tree reconstruction algorithm, Code = Code + Increment |
94 | only if BitLength(i) is not zero. (Pretty obvious.) |
95 | 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19) |
96 | 12. Note: length code 284 can represent 227-258, but length code 285 |
97 | really is 258. The last length deserves its own, short code |
98 | since it gets used a lot in very redundant files. The length |
99 | 258 is special since 258 - 3 (the min match length) is 255. |
100 | 13. The literal/length and distance code bit lengths are read as a |
101 | single stream of lengths. It is possible (and advantageous) for |
102 | a repeat code (16, 17, or 18) to go across the boundary between |
103 | the two sets of lengths. |
104 | */ |
105 | #include <linux/compiler.h> |
106 | |
107 | #ifdef RCSID |
108 | static char rcsid[] = "#Id: inflate.c,v 0.14 1993/06/10 13:27:04 jloup Exp #"; |
109 | #endif |
110 | |
111 | #ifndef STATIC |
112 | |
113 | #if defined(STDC_HEADERS) || defined(HAVE_STDLIB_H) |
114 | # include <sys/types.h> |
115 | # include <stdlib.h> |
116 | #endif |
117 | |
118 | #include "gzip.h" |
119 | #define STATIC |
120 | #endif /* !STATIC */ |
121 | |
122 | #ifndef INIT |
123 | #define INIT |
124 | #endif |
125 | |
126 | #define slide window |
127 | |
128 | /* Huffman code lookup table entry--this entry is four bytes for machines |
129 | that have 16-bit pointers (e.g. PC's in the small or medium model). |
130 | Valid extra bits are 0..13. e == 15 is EOB (end of block), e == 16 |
131 | means that v is a literal, 16 < e < 32 means that v is a pointer to |
132 | the next table, which codes e - 16 bits, and lastly e == 99 indicates |
133 | an unused code. If a code with e == 99 is looked up, this implies an |
134 | error in the data. */ |
135 | struct huft { |
136 | uch e; /* number of extra bits or operation */ |
137 | uch b; /* number of bits in this code or subcode */ |
138 | union { |
139 | ush n; /* literal, length base, or distance base */ |
140 | struct huft *t; /* pointer to next level of table */ |
141 | } v; |
142 | }; |
143 | |
144 | |
145 | /* Function prototypes */ |
146 | STATIC int INIT huft_build OF((unsigned *, unsigned, unsigned, |
147 | const ush *, const ush *, struct huft **, int *)); |
148 | STATIC int INIT huft_free OF((struct huft *)); |
149 | STATIC int INIT inflate_codes OF((struct huft *, struct huft *, int, int)); |
150 | STATIC int INIT inflate_stored OF((void)); |
151 | STATIC int INIT inflate_fixed OF((void)); |
152 | STATIC int INIT inflate_dynamic OF((void)); |
153 | STATIC int INIT inflate_block OF((int *)); |
154 | STATIC int INIT inflate OF((void)); |
155 | |
156 | |
157 | /* The inflate algorithm uses a sliding 32 K byte window on the uncompressed |
158 | stream to find repeated byte strings. This is implemented here as a |
159 | circular buffer. The index is updated simply by incrementing and then |
160 | ANDing with 0x7fff (32K-1). */ |
161 | /* It is left to other modules to supply the 32 K area. It is assumed |
162 | to be usable as if it were declared "uch slide[32768];" or as just |
163 | "uch *slide;" and then malloc'ed in the latter case. The definition |
164 | must be in unzip.h, included above. */ |
165 | /* unsigned wp; current position in slide */ |
166 | #define wp outcnt |
167 | #define flush_output(w) (wp=(w),flush_window()) |
168 | |
169 | /* Tables for deflate from PKZIP's appnote.txt. */ |
170 | static const unsigned border[] = { /* Order of the bit length code lengths */ |
171 | 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; |
172 | static const ush cplens[] = { /* Copy lengths for literal codes 257..285 */ |
173 | 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, |
174 | 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0}; |
175 | /* note: see note #13 above about the 258 in this list. */ |
176 | static const ush cplext[] = { /* Extra bits for literal codes 257..285 */ |
177 | 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, |
178 | 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 99, 99}; /* 99==invalid */ |
179 | static const ush cpdist[] = { /* Copy offsets for distance codes 0..29 */ |
180 | 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, |
181 | 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145, |
182 | 8193, 12289, 16385, 24577}; |
183 | static const ush cpdext[] = { /* Extra bits for distance codes */ |
184 | 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, |
185 | 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, |
186 | 12, 12, 13, 13}; |
187 | |
188 | |
189 | |
190 | /* Macros for inflate() bit peeking and grabbing. |
191 | The usage is: |
192 | |
193 | NEEDBITS(j) |
194 | x = b & mask_bits[j]; |
195 | DUMPBITS(j) |
196 | |
197 | where NEEDBITS makes sure that b has at least j bits in it, and |
198 | DUMPBITS removes the bits from b. The macros use the variable k |
199 | for the number of bits in b. Normally, b and k are register |
200 | variables for speed, and are initialized at the beginning of a |
201 | routine that uses these macros from a global bit buffer and count. |
202 | |
203 | If we assume that EOB will be the longest code, then we will never |
204 | ask for bits with NEEDBITS that are beyond the end of the stream. |
205 | So, NEEDBITS should not read any more bytes than are needed to |
206 | meet the request. Then no bytes need to be "returned" to the buffer |
207 | at the end of the last block. |
208 | |
209 | However, this assumption is not true for fixed blocks--the EOB code |
210 | is 7 bits, but the other literal/length codes can be 8 or 9 bits. |
211 | (The EOB code is shorter than other codes because fixed blocks are |
212 | generally short. So, while a block always has an EOB, many other |
213 | literal/length codes have a significantly lower probability of |
214 | showing up at all.) However, by making the first table have a |
215 | lookup of seven bits, the EOB code will be found in that first |
216 | lookup, and so will not require that too many bits be pulled from |
217 | the stream. |
218 | */ |
219 | |
220 | STATIC ulg bb; /* bit buffer */ |
221 | STATIC unsigned bk; /* bits in bit buffer */ |
222 | |
223 | STATIC const ush mask_bits[] = { |
224 | 0x0000, |
225 | 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff, |
226 | 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff |
227 | }; |
228 | |
229 | #define NEXTBYTE() ({ int v = get_byte(); if (v < 0) goto underrun; (uch)v; }) |
230 | #define NEEDBITS(n) {while(k<(n)){b|=((ulg)NEXTBYTE())<<k;k+=8;}} |
231 | #define DUMPBITS(n) {b>>=(n);k-=(n);} |
232 | |
233 | |
234 | /* |
235 | Huffman code decoding is performed using a multi-level table lookup. |
236 | The fastest way to decode is to simply build a lookup table whose |
237 | size is determined by the longest code. However, the time it takes |
238 | to build this table can also be a factor if the data being decoded |
239 | is not very long. The most common codes are necessarily the |
240 | shortest codes, so those codes dominate the decoding time, and hence |
241 | the speed. The idea is you can have a shorter table that decodes the |
242 | shorter, more probable codes, and then point to subsidiary tables for |
243 | the longer codes. The time it costs to decode the longer codes is |
244 | then traded against the time it takes to make longer tables. |
245 | |
246 | This results of this trade are in the variables lbits and dbits |
247 | below. lbits is the number of bits the first level table for literal/ |
248 | length codes can decode in one step, and dbits is the same thing for |
249 | the distance codes. Subsequent tables are also less than or equal to |
250 | those sizes. These values may be adjusted either when all of the |
251 | codes are shorter than that, in which case the longest code length in |
252 | bits is used, or when the shortest code is *longer* than the requested |
253 | table size, in which case the length of the shortest code in bits is |
254 | used. |
255 | |
256 | There are two different values for the two tables, since they code a |
257 | different number of possibilities each. The literal/length table |
258 | codes 286 possible values, or in a flat code, a little over eight |
259 | bits. The distance table codes 30 possible values, or a little less |
260 | than five bits, flat. The optimum values for speed end up being |
261 | about one bit more than those, so lbits is 8+1 and dbits is 5+1. |
262 | The optimum values may differ though from machine to machine, and |
263 | possibly even between compilers. Your mileage may vary. |
264 | */ |
265 | |
266 | |
267 | STATIC const int lbits = 9; /* bits in base literal/length lookup table */ |
268 | STATIC const int dbits = 6; /* bits in base distance lookup table */ |
269 | |
270 | |
271 | /* If BMAX needs to be larger than 16, then h and x[] should be ulg. */ |
272 | #define BMAX 16 /* maximum bit length of any code (16 for explode) */ |
273 | #define N_MAX 288 /* maximum number of codes in any set */ |
274 | |
275 | |
276 | STATIC unsigned hufts; /* track memory usage */ |
277 | |
278 | |
279 | STATIC int INIT huft_build( |
280 | unsigned *b, /* code lengths in bits (all assumed <= BMAX) */ |
281 | unsigned n, /* number of codes (assumed <= N_MAX) */ |
282 | unsigned s, /* number of simple-valued codes (0..s-1) */ |
283 | const ush *d, /* list of base values for non-simple codes */ |
284 | const ush *e, /* list of extra bits for non-simple codes */ |
285 | struct huft **t, /* result: starting table */ |
286 | int *m /* maximum lookup bits, returns actual */ |
287 | ) |
288 | /* Given a list of code lengths and a maximum table size, make a set of |
289 | tables to decode that set of codes. Return zero on success, one if |
290 | the given code set is incomplete (the tables are still built in this |
291 | case), two if the input is invalid (all zero length codes or an |
292 | oversubscribed set of lengths), and three if not enough memory. */ |
293 | { |
294 | unsigned a; /* counter for codes of length k */ |
295 | unsigned c[BMAX+1]; /* bit length count table */ |
296 | unsigned f; /* i repeats in table every f entries */ |
297 | int g; /* maximum code length */ |
298 | int h; /* table level */ |
299 | register unsigned i; /* counter, current code */ |
300 | register unsigned j; /* counter */ |
301 | register int k; /* number of bits in current code */ |
302 | int l; /* bits per table (returned in m) */ |
303 | register unsigned *p; /* pointer into c[], b[], or v[] */ |
304 | register struct huft *q; /* points to current table */ |
305 | struct huft r; /* table entry for structure assignment */ |
306 | struct huft *u[BMAX]; /* table stack */ |
307 | unsigned v[N_MAX]; /* values in order of bit length */ |
308 | register int w; /* bits before this table == (l * h) */ |
309 | unsigned x[BMAX+1]; /* bit offsets, then code stack */ |
310 | unsigned *xp; /* pointer into x */ |
311 | int y; /* number of dummy codes added */ |
312 | unsigned z; /* number of entries in current table */ |
313 | |
314 | DEBG("huft1 "); |
315 | |
316 | /* Generate counts for each bit length */ |
317 | memzero(c, sizeof(c)); |
318 | p = b; i = n; |
319 | do { |
320 | Tracecv(*p, (stderr, (n-i >= ' ' && n-i <= '~' ? "%c %d\n" : "0x%x %d\n"), |
321 | n-i, *p)); |
322 | c[*p]++; /* assume all entries <= BMAX */ |
323 | p++; /* Can't combine with above line (Solaris bug) */ |
324 | } while (--i); |
325 | if (c[0] == n) /* null input--all zero length codes */ |
326 | { |
327 | *t = (struct huft *)NULL; |
328 | *m = 0; |
329 | return 2; |
330 | } |
331 | |
332 | DEBG("huft2 "); |
333 | |
334 | /* Find minimum and maximum length, bound *m by those */ |
335 | l = *m; |
336 | for (j = 1; j <= BMAX; j++) |
337 | if (c[j]) |
338 | break; |
339 | k = j; /* minimum code length */ |
340 | if ((unsigned)l < j) |
341 | l = j; |
342 | for (i = BMAX; i; i--) |
343 | if (c[i]) |
344 | break; |
345 | g = i; /* maximum code length */ |
346 | if ((unsigned)l > i) |
347 | l = i; |
348 | *m = l; |
349 | |
350 | DEBG("huft3 "); |
351 | |
352 | /* Adjust last length count to fill out codes, if needed */ |
353 | for (y = 1 << j; j < i; j++, y <<= 1) |
354 | if ((y -= c[j]) < 0) |
355 | return 2; /* bad input: more codes than bits */ |
356 | if ((y -= c[i]) < 0) |
357 | return 2; |
358 | c[i] += y; |
359 | |
360 | DEBG("huft4 "); |
361 | |
362 | /* Generate starting offsets into the value table for each length */ |
363 | x[1] = j = 0; |
364 | p = c + 1; xp = x + 2; |
365 | while (--i) { /* note that i == g from above */ |
366 | *xp++ = (j += *p++); |
367 | } |
368 | |
369 | DEBG("huft5 "); |
370 | |
371 | /* Make a table of values in order of bit lengths */ |
372 | p = b; i = 0; |
373 | do { |
374 | if ((j = *p++) != 0) |
375 | v[x[j]++] = i; |
376 | } while (++i < n); |
377 | n = x[g]; /* set n to length of v */ |
378 | |
379 | DEBG("h6 "); |
380 | |
381 | /* Generate the Huffman codes and for each, make the table entries */ |
382 | x[0] = i = 0; /* first Huffman code is zero */ |
383 | p = v; /* grab values in bit order */ |
384 | h = -1; /* no tables yet--level -1 */ |
385 | w = -l; /* bits decoded == (l * h) */ |
386 | u[0] = (struct huft *)NULL; /* just to keep compilers happy */ |
387 | q = (struct huft *)NULL; /* ditto */ |
388 | z = 0; /* ditto */ |
389 | DEBG("h6a "); |
390 | |
391 | /* go through the bit lengths (k already is bits in shortest code) */ |
392 | for (; k <= g; k++) |
393 | { |
394 | DEBG("h6b "); |
395 | a = c[k]; |
396 | while (a--) |
397 | { |
398 | DEBG("h6b1 "); |
399 | /* here i is the Huffman code of length k bits for value *p */ |
400 | /* make tables up to required level */ |
401 | while (k > w + l) |
402 | { |
403 | DEBG1("1 "); |
404 | h++; |
405 | w += l; /* previous table always l bits */ |
406 | |
407 | /* compute minimum size table less than or equal to l bits */ |
408 | z = (z = g - w) > (unsigned)l ? l : z; /* upper limit on table size */ |
409 | if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */ |
410 | { /* too few codes for k-w bit table */ |
411 | DEBG1("2 "); |
412 | f -= a + 1; /* deduct codes from patterns left */ |
413 | xp = c + k; |
414 | if (j < z) |
415 | while (++j < z) /* try smaller tables up to z bits */ |
416 | { |
417 | if ((f <<= 1) <= *++xp) |
418 | break; /* enough codes to use up j bits */ |
419 | f -= *xp; /* else deduct codes from patterns */ |
420 | } |
421 | } |
422 | DEBG1("3 "); |
423 | z = 1 << j; /* table entries for j-bit table */ |
424 | |
425 | /* allocate and link in new table */ |
426 | if ((q = (struct huft *)malloc((z + 1)*sizeof(struct huft))) == |
427 | (struct huft *)NULL) |
428 | { |
429 | if (h) |
430 | huft_free(u[0]); |
431 | return 3; /* not enough memory */ |
432 | } |
433 | DEBG1("4 "); |
434 | hufts += z + 1; /* track memory usage */ |
435 | *t = q + 1; /* link to list for huft_free() */ |
436 | *(t = &(q->v.t)) = (struct huft *)NULL; |
437 | u[h] = ++q; /* table starts after link */ |
438 | |
439 | DEBG1("5 "); |
440 | /* connect to last table, if there is one */ |
441 | if (h) |
442 | { |
443 | x[h] = i; /* save pattern for backing up */ |
444 | r.b = (uch)l; /* bits to dump before this table */ |
445 | r.e = (uch)(16 + j); /* bits in this table */ |
446 | r.v.t = q; /* pointer to this table */ |
447 | j = i >> (w - l); /* (get around Turbo C bug) */ |
448 | u[h-1][j] = r; /* connect to last table */ |
449 | } |
450 | DEBG1("6 "); |
451 | } |
452 | DEBG("h6c "); |
453 | |
454 | /* set up table entry in r */ |
455 | r.b = (uch)(k - w); |
456 | if (p >= v + n) |
457 | r.e = 99; /* out of values--invalid code */ |
458 | else if (*p < s) |
459 | { |
460 | r.e = (uch)(*p < 256 ? 16 : 15); /* 256 is end-of-block code */ |
461 | r.v.n = (ush)(*p); /* simple code is just the value */ |
462 | p++; /* one compiler does not like *p++ */ |
463 | } |
464 | else |
465 | { |
466 | r.e = (uch)e[*p - s]; /* non-simple--look up in lists */ |
467 | r.v.n = d[*p++ - s]; |
468 | } |
469 | DEBG("h6d "); |
470 | |
471 | /* fill code-like entries with r */ |
472 | f = 1 << (k - w); |
473 | for (j = i >> w; j < z; j += f) |
474 | q[j] = r; |
475 | |
476 | /* backwards increment the k-bit code i */ |
477 | for (j = 1 << (k - 1); i & j; j >>= 1) |
478 | i ^= j; |
479 | i ^= j; |
480 | |
481 | /* backup over finished tables */ |
482 | while ((i & ((1 << w) - 1)) != x[h]) |
483 | { |
484 | h--; /* don't need to update q */ |
485 | w -= l; |
486 | } |
487 | DEBG("h6e "); |
488 | } |
489 | DEBG("h6f "); |
490 | } |
491 | |
492 | DEBG("huft7 "); |
493 | |
494 | /* Return true (1) if we were given an incomplete table */ |
495 | return y != 0 && g != 1; |
496 | } |
497 | |
498 | |
499 | |
500 | STATIC int INIT huft_free( |
501 | struct huft *t /* table to free */ |
502 | ) |
503 | /* Free the malloc'ed tables built by huft_build(), which makes a linked |
504 | list of the tables it made, with the links in a dummy first entry of |
505 | each table. */ |
506 | { |
507 | register struct huft *p, *q; |
508 | |
509 | |
510 | /* Go through linked list, freeing from the malloced (t[-1]) address. */ |
511 | p = t; |
512 | while (p != (struct huft *)NULL) |
513 | { |
514 | q = (--p)->v.t; |
515 | free((char*)p); |
516 | p = q; |
517 | } |
518 | return 0; |
519 | } |
520 | |
521 | |
522 | STATIC int INIT inflate_codes( |
523 | struct huft *tl, /* literal/length decoder tables */ |
524 | struct huft *td, /* distance decoder tables */ |
525 | int bl, /* number of bits decoded by tl[] */ |
526 | int bd /* number of bits decoded by td[] */ |
527 | ) |
528 | /* inflate (decompress) the codes in a deflated (compressed) block. |
529 | Return an error code or zero if it all goes ok. */ |
530 | { |
531 | register unsigned e; /* table entry flag/number of extra bits */ |
532 | unsigned n, d; /* length and index for copy */ |
533 | unsigned w; /* current window position */ |
534 | struct huft *t; /* pointer to table entry */ |
535 | unsigned ml, md; /* masks for bl and bd bits */ |
536 | register ulg b; /* bit buffer */ |
537 | register unsigned k; /* number of bits in bit buffer */ |
538 | |
539 | |
540 | /* make local copies of globals */ |
541 | b = bb; /* initialize bit buffer */ |
542 | k = bk; |
543 | w = wp; /* initialize window position */ |
544 | |
545 | /* inflate the coded data */ |
546 | ml = mask_bits[bl]; /* precompute masks for speed */ |
547 | md = mask_bits[bd]; |
548 | for (;;) /* do until end of block */ |
549 | { |
550 | NEEDBITS((unsigned)bl) |
551 | if ((e = (t = tl + ((unsigned)b & ml))->e) > 16) |
552 | do { |
553 | if (e == 99) |
554 | return 1; |
555 | DUMPBITS(t->b) |
556 | e -= 16; |
557 | NEEDBITS(e) |
558 | } while ((e = (t = t->v.t + ((unsigned)b & mask_bits[e]))->e) > 16); |
559 | DUMPBITS(t->b) |
560 | if (e == 16) /* then it's a literal */ |
561 | { |
562 | slide[w++] = (uch)t->v.n; |
563 | Tracevv((stderr, "%c", slide[w-1])); |
564 | if (w == WSIZE) |
565 | { |
566 | flush_output(w); |
567 | w = 0; |
568 | } |
569 | } |
570 | else /* it's an EOB or a length */ |
571 | { |
572 | /* exit if end of block */ |
573 | if (e == 15) |
574 | break; |
575 | |
576 | /* get length of block to copy */ |
577 | NEEDBITS(e) |
578 | n = t->v.n + ((unsigned)b & mask_bits[e]); |
579 | DUMPBITS(e); |
580 | |
581 | /* decode distance of block to copy */ |
582 | NEEDBITS((unsigned)bd) |
583 | if ((e = (t = td + ((unsigned)b & md))->e) > 16) |
584 | do { |
585 | if (e == 99) |
586 | return 1; |
587 | DUMPBITS(t->b) |
588 | e -= 16; |
589 | NEEDBITS(e) |
590 | } while ((e = (t = t->v.t + ((unsigned)b & mask_bits[e]))->e) > 16); |
591 | DUMPBITS(t->b) |
592 | NEEDBITS(e) |
593 | d = w - t->v.n - ((unsigned)b & mask_bits[e]); |
594 | DUMPBITS(e) |
595 | Tracevv((stderr,"\\[%d,%d]", w-d, n)); |
596 | |
597 | /* do the copy */ |
598 | do { |
599 | n -= (e = (e = WSIZE - ((d &= WSIZE-1) > w ? d : w)) > n ? n : e); |
600 | #if !defined(NOMEMCPY) && !defined(DEBUG) |
601 | if (w - d >= e) /* (this test assumes unsigned comparison) */ |
602 | { |
603 | memcpy(slide + w, slide + d, e); |
604 | w += e; |
605 | d += e; |
606 | } |
607 | else /* do it slow to avoid memcpy() overlap */ |
608 | #endif /* !NOMEMCPY */ |
609 | do { |
610 | slide[w++] = slide[d++]; |
611 | Tracevv((stderr, "%c", slide[w-1])); |
612 | } while (--e); |
613 | if (w == WSIZE) |
614 | { |
615 | flush_output(w); |
616 | w = 0; |
617 | } |
618 | } while (n); |
619 | } |
620 | } |
621 | |
622 | |
623 | /* restore the globals from the locals */ |
624 | wp = w; /* restore global window pointer */ |
625 | bb = b; /* restore global bit buffer */ |
626 | bk = k; |
627 | |
628 | /* done */ |
629 | return 0; |
630 | |
631 | underrun: |
632 | return 4; /* Input underrun */ |
633 | } |
634 | |
635 | |
636 | |
637 | STATIC int INIT inflate_stored(void) |
638 | /* "decompress" an inflated type 0 (stored) block. */ |
639 | { |
640 | unsigned n; /* number of bytes in block */ |
641 | unsigned w; /* current window position */ |
642 | register ulg b; /* bit buffer */ |
643 | register unsigned k; /* number of bits in bit buffer */ |
644 | |
645 | DEBG("<stor"); |
646 | |
647 | /* make local copies of globals */ |
648 | b = bb; /* initialize bit buffer */ |
649 | k = bk; |
650 | w = wp; /* initialize window position */ |
651 | |
652 | |
653 | /* go to byte boundary */ |
654 | n = k & 7; |
655 | DUMPBITS(n); |
656 | |
657 | |
658 | /* get the length and its complement */ |
659 | NEEDBITS(16) |
660 | n = ((unsigned)b & 0xffff); |
661 | DUMPBITS(16) |
662 | NEEDBITS(16) |
663 | if (n != (unsigned)((~b) & 0xffff)) |
664 | return 1; /* error in compressed data */ |
665 | DUMPBITS(16) |
666 | |
667 | |
668 | /* read and output the compressed data */ |
669 | while (n--) |
670 | { |
671 | NEEDBITS(8) |
672 | slide[w++] = (uch)b; |
673 | if (w == WSIZE) |
674 | { |
675 | flush_output(w); |
676 | w = 0; |
677 | } |
678 | DUMPBITS(8) |
679 | } |
680 | |
681 | |
682 | /* restore the globals from the locals */ |
683 | wp = w; /* restore global window pointer */ |
684 | bb = b; /* restore global bit buffer */ |
685 | bk = k; |
686 | |
687 | DEBG(">"); |
688 | return 0; |
689 | |
690 | underrun: |
691 | return 4; /* Input underrun */ |
692 | } |
693 | |
694 | |
695 | /* |
696 | * We use `noinline' here to prevent gcc-3.5 from using too much stack space |
697 | */ |
698 | STATIC int noinline INIT inflate_fixed(void) |
699 | /* decompress an inflated type 1 (fixed Huffman codes) block. We should |
700 | either replace this with a custom decoder, or at least precompute the |
701 | Huffman tables. */ |
702 | { |
703 | int i; /* temporary variable */ |
704 | struct huft *tl; /* literal/length code table */ |
705 | struct huft *td; /* distance code table */ |
706 | int bl; /* lookup bits for tl */ |
707 | int bd; /* lookup bits for td */ |
708 | unsigned l[288]; /* length list for huft_build */ |
709 | |
710 | DEBG("<fix"); |
711 | |
712 | /* set up literal table */ |
713 | for (i = 0; i < 144; i++) |
714 | l[i] = 8; |
715 | for (; i < 256; i++) |
716 | l[i] = 9; |
717 | for (; i < 280; i++) |
718 | l[i] = 7; |
719 | for (; i < 288; i++) /* make a complete, but wrong code set */ |
720 | l[i] = 8; |
721 | bl = 7; |
722 | if ((i = huft_build(l, 288, 257, cplens, cplext, &tl, &bl)) != 0) |
723 | return i; |
724 | |
725 | |
726 | /* set up distance table */ |
727 | for (i = 0; i < 30; i++) /* make an incomplete code set */ |
728 | l[i] = 5; |
729 | bd = 5; |
730 | if ((i = huft_build(l, 30, 0, cpdist, cpdext, &td, &bd)) > 1) |
731 | { |
732 | huft_free(tl); |
733 | |
734 | DEBG(">"); |
735 | return i; |
736 | } |
737 | |
738 | |
739 | /* decompress until an end-of-block code */ |
740 | if (inflate_codes(tl, td, bl, bd)) |
741 | return 1; |
742 | |
743 | |
744 | /* free the decoding tables, return */ |
745 | huft_free(tl); |
746 | huft_free(td); |
747 | return 0; |
748 | } |
749 | |
750 | |
751 | /* |
752 | * We use `noinline' here to prevent gcc-3.5 from using too much stack space |
753 | */ |
754 | STATIC int noinline INIT inflate_dynamic(void) |
755 | /* decompress an inflated type 2 (dynamic Huffman codes) block. */ |
756 | { |
757 | int i; /* temporary variables */ |
758 | unsigned j; |
759 | unsigned l; /* last length */ |
760 | unsigned m; /* mask for bit lengths table */ |
761 | unsigned n; /* number of lengths to get */ |
762 | struct huft *tl; /* literal/length code table */ |
763 | struct huft *td; /* distance code table */ |
764 | int bl; /* lookup bits for tl */ |
765 | int bd; /* lookup bits for td */ |
766 | unsigned nb; /* number of bit length codes */ |
767 | unsigned nl; /* number of literal/length codes */ |
768 | unsigned nd; /* number of distance codes */ |
769 | #ifdef PKZIP_BUG_WORKAROUND |
770 | unsigned ll[288+32]; /* literal/length and distance code lengths */ |
771 | #else |
772 | unsigned ll[286+30]; /* literal/length and distance code lengths */ |
773 | #endif |
774 | register ulg b; /* bit buffer */ |
775 | register unsigned k; /* number of bits in bit buffer */ |
776 | |
777 | DEBG("<dyn"); |
778 | |
779 | /* make local bit buffer */ |
780 | b = bb; |
781 | k = bk; |
782 | |
783 | |
784 | /* read in table lengths */ |
785 | NEEDBITS(5) |
786 | nl = 257 + ((unsigned)b & 0x1f); /* number of literal/length codes */ |
787 | DUMPBITS(5) |
788 | NEEDBITS(5) |
789 | nd = 1 + ((unsigned)b & 0x1f); /* number of distance codes */ |
790 | DUMPBITS(5) |
791 | NEEDBITS(4) |
792 | nb = 4 + ((unsigned)b & 0xf); /* number of bit length codes */ |
793 | DUMPBITS(4) |
794 | #ifdef PKZIP_BUG_WORKAROUND |
795 | if (nl > 288 || nd > 32) |
796 | #else |
797 | if (nl > 286 || nd > 30) |
798 | #endif |
799 | return 1; /* bad lengths */ |
800 | |
801 | DEBG("dyn1 "); |
802 | |
803 | /* read in bit-length-code lengths */ |
804 | for (j = 0; j < nb; j++) |
805 | { |
806 | NEEDBITS(3) |
807 | ll[border[j]] = (unsigned)b & 7; |
808 | DUMPBITS(3) |
809 | } |
810 | for (; j < 19; j++) |
811 | ll[border[j]] = 0; |
812 | |
813 | DEBG("dyn2 "); |
814 | |
815 | /* build decoding table for trees--single level, 7 bit lookup */ |
816 | bl = 7; |
817 | if ((i = huft_build(ll, 19, 19, NULL, NULL, &tl, &bl)) != 0) |
818 | { |
819 | if (i == 1) |
820 | huft_free(tl); |
821 | return i; /* incomplete code set */ |
822 | } |
823 | |
824 | DEBG("dyn3 "); |
825 | |
826 | /* read in literal and distance code lengths */ |
827 | n = nl + nd; |
828 | m = mask_bits[bl]; |
829 | i = l = 0; |
830 | while ((unsigned)i < n) |
831 | { |
832 | NEEDBITS((unsigned)bl) |
833 | j = (td = tl + ((unsigned)b & m))->b; |
834 | DUMPBITS(j) |
835 | j = td->v.n; |
836 | if (j < 16) /* length of code in bits (0..15) */ |
837 | ll[i++] = l = j; /* save last length in l */ |
838 | else if (j == 16) /* repeat last length 3 to 6 times */ |
839 | { |
840 | NEEDBITS(2) |
841 | j = 3 + ((unsigned)b & 3); |
842 | DUMPBITS(2) |
843 | if ((unsigned)i + j > n) |
844 | return 1; |
845 | while (j--) |
846 | ll[i++] = l; |
847 | } |
848 | else if (j == 17) /* 3 to 10 zero length codes */ |
849 | { |
850 | NEEDBITS(3) |
851 | j = 3 + ((unsigned)b & 7); |
852 | DUMPBITS(3) |
853 | if ((unsigned)i + j > n) |
854 | return 1; |
855 | while (j--) |
856 | ll[i++] = 0; |
857 | l = 0; |
858 | } |
859 | else /* j == 18: 11 to 138 zero length codes */ |
860 | { |
861 | NEEDBITS(7) |
862 | j = 11 + ((unsigned)b & 0x7f); |
863 | DUMPBITS(7) |
864 | if ((unsigned)i + j > n) |
865 | return 1; |
866 | while (j--) |
867 | ll[i++] = 0; |
868 | l = 0; |
869 | } |
870 | } |
871 | |
872 | DEBG("dyn4 "); |
873 | |
874 | /* free decoding table for trees */ |
875 | huft_free(tl); |
876 | |
877 | DEBG("dyn5 "); |
878 | |
879 | /* restore the global bit buffer */ |
880 | bb = b; |
881 | bk = k; |
882 | |
883 | DEBG("dyn5a "); |
884 | |
885 | /* build the decoding tables for literal/length and distance codes */ |
886 | bl = lbits; |
887 | if ((i = huft_build(ll, nl, 257, cplens, cplext, &tl, &bl)) != 0) |
888 | { |
889 | DEBG("dyn5b "); |
890 | if (i == 1) { |
891 | error("incomplete literal tree"); |
892 | huft_free(tl); |
893 | } |
894 | return i; /* incomplete code set */ |
895 | } |
896 | DEBG("dyn5c "); |
897 | bd = dbits; |
898 | if ((i = huft_build(ll + nl, nd, 0, cpdist, cpdext, &td, &bd)) != 0) |
899 | { |
900 | DEBG("dyn5d "); |
901 | if (i == 1) { |
902 | error("incomplete distance tree"); |
903 | #ifdef PKZIP_BUG_WORKAROUND |
904 | i = 0; |
905 | } |
906 | #else |
907 | huft_free(td); |
908 | } |
909 | huft_free(tl); |
910 | return i; /* incomplete code set */ |
911 | #endif |
912 | } |
913 | |
914 | DEBG("dyn6 "); |
915 | |
916 | /* decompress until an end-of-block code */ |
917 | if (inflate_codes(tl, td, bl, bd)) |
918 | return 1; |
919 | |
920 | DEBG("dyn7 "); |
921 | |
922 | /* free the decoding tables, return */ |
923 | huft_free(tl); |
924 | huft_free(td); |
925 | |
926 | DEBG(">"); |
927 | return 0; |
928 | |
929 | underrun: |
930 | return 4; /* Input underrun */ |
931 | } |
932 | |
933 | |
934 | |
935 | STATIC int INIT inflate_block( |
936 | int *e /* last block flag */ |
937 | ) |
938 | /* decompress an inflated block */ |
939 | { |
940 | unsigned t; /* block type */ |
941 | register ulg b; /* bit buffer */ |
942 | register unsigned k; /* number of bits in bit buffer */ |
943 | |
944 | DEBG("<blk"); |
945 | |
946 | /* make local bit buffer */ |
947 | b = bb; |
948 | k = bk; |
949 | |
950 | |
951 | /* read in last block bit */ |
952 | NEEDBITS(1) |
953 | *e = (int)b & 1; |
954 | DUMPBITS(1) |
955 | |
956 | |
957 | /* read in block type */ |
958 | NEEDBITS(2) |
959 | t = (unsigned)b & 3; |
960 | DUMPBITS(2) |
961 | |
962 | |
963 | /* restore the global bit buffer */ |
964 | bb = b; |
965 | bk = k; |
966 | |
967 | /* inflate that block type */ |
968 | if (t == 2) |
969 | return inflate_dynamic(); |
970 | if (t == 0) |
971 | return inflate_stored(); |
972 | if (t == 1) |
973 | return inflate_fixed(); |
974 | |
975 | DEBG(">"); |
976 | |
977 | /* bad block type */ |
978 | return 2; |
979 | |
980 | underrun: |
981 | return 4; /* Input underrun */ |
982 | } |
983 | |
984 | |
985 | |
986 | STATIC int INIT inflate(void) |
987 | /* decompress an inflated entry */ |
988 | { |
989 | int e; /* last block flag */ |
990 | int r; /* result code */ |
991 | unsigned h; /* maximum struct huft's malloc'ed */ |
992 | void *ptr; |
993 | |
994 | /* initialize window, bit buffer */ |
995 | wp = 0; |
996 | bk = 0; |
997 | bb = 0; |
998 | |
999 | |
1000 | /* decompress until the last block */ |
1001 | h = 0; |
1002 | do { |
1003 | hufts = 0; |
1004 | gzip_mark(&ptr); |
1005 | if ((r = inflate_block(&e)) != 0) { |
1006 | gzip_release(&ptr); |
1007 | return r; |
1008 | } |
1009 | gzip_release(&ptr); |
1010 | if (hufts > h) |
1011 | h = hufts; |
1012 | } while (!e); |
1013 | |
1014 | /* Undo too much lookahead. The next read will be byte aligned so we |
1015 | * can discard unused bits in the last meaningful byte. |
1016 | */ |
1017 | while (bk >= 8) { |
1018 | bk -= 8; |
1019 | inptr--; |
1020 | } |
1021 | |
1022 | /* flush out slide */ |
1023 | flush_output(wp); |
1024 | |
1025 | |
1026 | /* return success */ |
1027 | #ifdef DEBUG |
1028 | fprintf(stderr, "<%u> ", h); |
1029 | #endif /* DEBUG */ |
1030 | return 0; |
1031 | } |
1032 | |
1033 | /********************************************************************** |
1034 | * |
1035 | * The following are support routines for inflate.c |
1036 | * |
1037 | **********************************************************************/ |
1038 | |
1039 | static ulg crc_32_tab[256]; |
1040 | static ulg crc; /* initialized in makecrc() so it'll reside in bss */ |
1041 | #define CRC_VALUE (crc ^ 0xffffffffUL) |
1042 | |
1043 | /* |
1044 | * Code to compute the CRC-32 table. Borrowed from |
1045 | * gzip-1.0.3/makecrc.c. |
1046 | */ |
1047 | |
1048 | static void INIT |
1049 | makecrc(void) |
1050 | { |
1051 | /* Not copyrighted 1990 Mark Adler */ |
1052 | |
1053 | unsigned long c; /* crc shift register */ |
1054 | unsigned long e; /* polynomial exclusive-or pattern */ |
1055 | int i; /* counter for all possible eight bit values */ |
1056 | int k; /* byte being shifted into crc apparatus */ |
1057 | |
1058 | /* terms of polynomial defining this crc (except x^32): */ |
1059 | static const int p[] = {0,1,2,4,5,7,8,10,11,12,16,22,23,26}; |
1060 | |
1061 | /* Make exclusive-or pattern from polynomial */ |
1062 | e = 0; |
1063 | for (i = 0; i < sizeof(p)/sizeof(int); i++) |
1064 | e |= 1L << (31 - p[i]); |
1065 | |
1066 | crc_32_tab[0] = 0; |
1067 | |
1068 | for (i = 1; i < 256; i++) |
1069 | { |
1070 | c = 0; |
1071 | for (k = i | 256; k != 1; k >>= 1) |
1072 | { |
1073 | c = c & 1 ? (c >> 1) ^ e : c >> 1; |
1074 | if (k & 1) |
1075 | c ^= e; |
1076 | } |
1077 | crc_32_tab[i] = c; |
1078 | } |
1079 | |
1080 | /* this is initialized here so this code could reside in ROM */ |
1081 | crc = (ulg)0xffffffffUL; /* shift register contents */ |
1082 | } |
1083 | |
1084 | /* gzip flag byte */ |
1085 | #define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */ |
1086 | #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */ |
1087 | #define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */ |
1088 | #define ORIG_NAME 0x08 /* bit 3 set: original file name present */ |
1089 | #define COMMENT 0x10 /* bit 4 set: file comment present */ |
1090 | #define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */ |
1091 | #define RESERVED 0xC0 /* bit 6,7: reserved */ |
1092 | |
1093 | /* |
1094 | * Do the uncompression! |
1095 | */ |
1096 | static int INIT gunzip(void) |
1097 | { |
1098 | uch flags; |
1099 | unsigned char magic[2]; /* magic header */ |
1100 | char method; |
1101 | ulg orig_crc = 0; /* original crc */ |
1102 | ulg orig_len = 0; /* original uncompressed length */ |
1103 | int res; |
1104 | |
1105 | magic[0] = NEXTBYTE(); |
1106 | magic[1] = NEXTBYTE(); |
1107 | method = NEXTBYTE(); |
1108 | |
1109 | if (magic[0] != 037 || |
1110 | ((magic[1] != 0213) && (magic[1] != 0236))) { |
1111 | error("bad gzip magic numbers"); |
1112 | return -1; |
1113 | } |
1114 | |
1115 | /* We only support method #8, DEFLATED */ |
1116 | if (method != 8) { |
1117 | error("internal error, invalid method"); |
1118 | return -1; |
1119 | } |
1120 | |
1121 | flags = (uch)get_byte(); |
1122 | if ((flags & ENCRYPTED) != 0) { |
1123 | error("Input is encrypted"); |
1124 | return -1; |
1125 | } |
1126 | if ((flags & CONTINUATION) != 0) { |
1127 | error("Multi part input"); |
1128 | return -1; |
1129 | } |
1130 | if ((flags & RESERVED) != 0) { |
1131 | error("Input has invalid flags"); |
1132 | return -1; |
1133 | } |
1134 | NEXTBYTE(); /* Get timestamp */ |
1135 | NEXTBYTE(); |
1136 | NEXTBYTE(); |
1137 | NEXTBYTE(); |
1138 | |
1139 | (void)NEXTBYTE(); /* Ignore extra flags for the moment */ |
1140 | (void)NEXTBYTE(); /* Ignore OS type for the moment */ |
1141 | |
1142 | if ((flags & EXTRA_FIELD) != 0) { |
1143 | unsigned len = (unsigned)NEXTBYTE(); |
1144 | len |= ((unsigned)NEXTBYTE())<<8; |
1145 | while (len--) (void)NEXTBYTE(); |
1146 | } |
1147 | |
1148 | /* Get original file name if it was truncated */ |
1149 | if ((flags & ORIG_NAME) != 0) { |
1150 | /* Discard the old name */ |
1151 | while (NEXTBYTE() != 0) /* null */ ; |
1152 | } |
1153 | |
1154 | /* Discard file comment if any */ |
1155 | if ((flags & COMMENT) != 0) { |
1156 | while (NEXTBYTE() != 0) /* null */ ; |
1157 | } |
1158 | |
1159 | /* Decompress */ |
1160 | if ((res = inflate())) { |
1161 | switch (res) { |
1162 | case 0: |
1163 | break; |
1164 | case 1: |
1165 | error("invalid compressed format (err=1)"); |
1166 | break; |
1167 | case 2: |
1168 | error("invalid compressed format (err=2)"); |
1169 | break; |
1170 | case 3: |
1171 | error("out of memory"); |
1172 | break; |
1173 | case 4: |
1174 | error("out of input data"); |
1175 | break; |
1176 | default: |
1177 | error("invalid compressed format (other)"); |
1178 | } |
1179 | return -1; |
1180 | } |
1181 | |
1182 | /* Get the crc and original length */ |
1183 | /* crc32 (see algorithm.doc) |
1184 | * uncompressed input size modulo 2^32 |
1185 | */ |
1186 | orig_crc = (ulg) NEXTBYTE(); |
1187 | orig_crc |= (ulg) NEXTBYTE() << 8; |
1188 | orig_crc |= (ulg) NEXTBYTE() << 16; |
1189 | orig_crc |= (ulg) NEXTBYTE() << 24; |
1190 | |
1191 | orig_len = (ulg) NEXTBYTE(); |
1192 | orig_len |= (ulg) NEXTBYTE() << 8; |
1193 | orig_len |= (ulg) NEXTBYTE() << 16; |
1194 | orig_len |= (ulg) NEXTBYTE() << 24; |
1195 | |
1196 | /* Validate decompression */ |
1197 | if (orig_crc != CRC_VALUE) { |
1198 | error("crc error"); |
1199 | return -1; |
1200 | } |
1201 | if (orig_len != bytes_out) { |
1202 | error("length error"); |
1203 | return -1; |
1204 | } |
1205 | return 0; |
1206 | |
1207 | underrun: /* NEXTBYTE() goto's here if needed */ |
1208 | error("out of input data"); |
1209 | return -1; |
1210 | } |
1211 | |
1212 |