source: MondoRescue/branches/3.2/mindi-busybox/archival/libarchive/decompress_unzip.c@ 3186

Last change on this file since 3186 was 2725, checked in by Bruno Cornec, 13 years ago
  • Update mindi-busybox to 1.18.3 to avoid problems with the tar command which is now failing on recent versions with busybox 1.7.3
  • Property svn:eol-style set to native
File size: 34.7 KB
Line 
1/* vi: set sw=4 ts=4: */
2/*
3 * gunzip implementation for busybox
4 *
5 * Based on GNU gzip v1.2.4 Copyright (C) 1992-1993 Jean-loup Gailly.
6 *
7 * Originally adjusted for busybox by Sven Rudolph <sr1@inf.tu-dresden.de>
8 * based on gzip sources
9 *
10 * Adjusted further by Erik Andersen <andersen@codepoet.org> to support
11 * files as well as stdin/stdout, and to generally behave itself wrt
12 * command line handling.
13 *
14 * General cleanup to better adhere to the style guide and make use of standard
15 * busybox functions by Glenn McGrath
16 *
17 * read_gz interface + associated hacking by Laurence Anderson
18 *
19 * Fixed huft_build() so decoding end-of-block code does not grab more bits
20 * than necessary (this is required by unzip applet), added inflate_cleanup()
21 * to free leaked bytebuffer memory (used in unzip.c), and some minor style
22 * guide cleanups by Ed Clark
23 *
24 * gzip (GNU zip) -- compress files with zip algorithm and 'compress' interface
25 * Copyright (C) 1992-1993 Jean-loup Gailly
26 * The unzip code was written and put in the public domain by Mark Adler.
27 * Portions of the lzw code are derived from the public domain 'compress'
28 * written by Spencer Thomas, Joe Orost, James Woods, Jim McKie, Steve Davies,
29 * Ken Turkowski, Dave Mack and Peter Jannesen.
30 *
31 * See the file algorithm.doc for the compression algorithms and file formats.
32 *
33 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
34 */
35
36#include <setjmp.h>
37#include "libbb.h"
38#include "archive.h"
39
40typedef struct huft_t {
41 unsigned char e; /* number of extra bits or operation */
42 unsigned char b; /* number of bits in this code or subcode */
43 union {
44 unsigned short n; /* literal, length base, or distance base */
45 struct huft_t *t; /* pointer to next level of table */
46 } v;
47} huft_t;
48
49enum {
50 /* gunzip_window size--must be a power of two, and
51 * at least 32K for zip's deflate method */
52 GUNZIP_WSIZE = 0x8000,
53 /* If BMAX needs to be larger than 16, then h and x[] should be ulg. */
54 BMAX = 16, /* maximum bit length of any code (16 for explode) */
55 N_MAX = 288, /* maximum number of codes in any set */
56};
57
58
59/* This is somewhat complex-looking arrangement, but it allows
60 * to place decompressor state either in bss or in
61 * malloc'ed space simply by changing #defines below.
62 * Sizes on i386:
63 * text data bss dec hex
64 * 5256 0 108 5364 14f4 - bss
65 * 4915 0 0 4915 1333 - malloc
66 */
67#define STATE_IN_BSS 0
68#define STATE_IN_MALLOC 1
69
70
71typedef struct state_t {
72 off_t gunzip_bytes_out; /* number of output bytes */
73 uint32_t gunzip_crc;
74
75 int gunzip_src_fd;
76 unsigned gunzip_outbuf_count; /* bytes in output buffer */
77
78 unsigned char *gunzip_window;
79
80 uint32_t *gunzip_crc_table;
81
82 /* bitbuffer */
83 unsigned gunzip_bb; /* bit buffer */
84 unsigned char gunzip_bk; /* bits in bit buffer */
85
86 /* input (compressed) data */
87 unsigned char *bytebuffer; /* buffer itself */
88 off_t to_read; /* compressed bytes to read (unzip only, -1 for gunzip) */
89// unsigned bytebuffer_max; /* buffer size */
90 unsigned bytebuffer_offset; /* buffer position */
91 unsigned bytebuffer_size; /* how much data is there (size <= max) */
92
93 /* private data of inflate_codes() */
94 unsigned inflate_codes_ml; /* masks for bl and bd bits */
95 unsigned inflate_codes_md; /* masks for bl and bd bits */
96 unsigned inflate_codes_bb; /* bit buffer */
97 unsigned inflate_codes_k; /* number of bits in bit buffer */
98 unsigned inflate_codes_w; /* current gunzip_window position */
99 huft_t *inflate_codes_tl;
100 huft_t *inflate_codes_td;
101 unsigned inflate_codes_bl;
102 unsigned inflate_codes_bd;
103 unsigned inflate_codes_nn; /* length and index for copy */
104 unsigned inflate_codes_dd;
105
106 smallint resume_copy;
107
108 /* private data of inflate_get_next_window() */
109 smallint method; /* method == -1 for stored, -2 for codes */
110 smallint need_another_block;
111 smallint end_reached;
112
113 /* private data of inflate_stored() */
114 unsigned inflate_stored_n;
115 unsigned inflate_stored_b;
116 unsigned inflate_stored_k;
117 unsigned inflate_stored_w;
118
119 const char *error_msg;
120 jmp_buf error_jmp;
121} state_t;
122#define gunzip_bytes_out (S()gunzip_bytes_out )
123#define gunzip_crc (S()gunzip_crc )
124#define gunzip_src_fd (S()gunzip_src_fd )
125#define gunzip_outbuf_count (S()gunzip_outbuf_count)
126#define gunzip_window (S()gunzip_window )
127#define gunzip_crc_table (S()gunzip_crc_table )
128#define gunzip_bb (S()gunzip_bb )
129#define gunzip_bk (S()gunzip_bk )
130#define to_read (S()to_read )
131// #define bytebuffer_max (S()bytebuffer_max )
132// Both gunzip and unzip can use constant buffer size now (16k):
133#define bytebuffer_max 0x4000
134#define bytebuffer (S()bytebuffer )
135#define bytebuffer_offset (S()bytebuffer_offset )
136#define bytebuffer_size (S()bytebuffer_size )
137#define inflate_codes_ml (S()inflate_codes_ml )
138#define inflate_codes_md (S()inflate_codes_md )
139#define inflate_codes_bb (S()inflate_codes_bb )
140#define inflate_codes_k (S()inflate_codes_k )
141#define inflate_codes_w (S()inflate_codes_w )
142#define inflate_codes_tl (S()inflate_codes_tl )
143#define inflate_codes_td (S()inflate_codes_td )
144#define inflate_codes_bl (S()inflate_codes_bl )
145#define inflate_codes_bd (S()inflate_codes_bd )
146#define inflate_codes_nn (S()inflate_codes_nn )
147#define inflate_codes_dd (S()inflate_codes_dd )
148#define resume_copy (S()resume_copy )
149#define method (S()method )
150#define need_another_block (S()need_another_block )
151#define end_reached (S()end_reached )
152#define inflate_stored_n (S()inflate_stored_n )
153#define inflate_stored_b (S()inflate_stored_b )
154#define inflate_stored_k (S()inflate_stored_k )
155#define inflate_stored_w (S()inflate_stored_w )
156#define error_msg (S()error_msg )
157#define error_jmp (S()error_jmp )
158
159/* This is a generic part */
160#if STATE_IN_BSS /* Use global data segment */
161#define DECLARE_STATE /*nothing*/
162#define ALLOC_STATE /*nothing*/
163#define DEALLOC_STATE ((void)0)
164#define S() state.
165#define PASS_STATE /*nothing*/
166#define PASS_STATE_ONLY /*nothing*/
167#define STATE_PARAM /*nothing*/
168#define STATE_PARAM_ONLY void
169static state_t state;
170#endif
171
172#if STATE_IN_MALLOC /* Use malloc space */
173#define DECLARE_STATE state_t *state
174#define ALLOC_STATE (state = xzalloc(sizeof(*state)))
175#define DEALLOC_STATE free(state)
176#define S() state->
177#define PASS_STATE state,
178#define PASS_STATE_ONLY state
179#define STATE_PARAM state_t *state,
180#define STATE_PARAM_ONLY state_t *state
181#endif
182
183
184static const uint16_t mask_bits[] ALIGN2 = {
185 0x0000, 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
186 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
187};
188
189/* Copy lengths for literal codes 257..285 */
190static const uint16_t cplens[] ALIGN2 = {
191 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, 35, 43, 51, 59,
192 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0
193};
194
195/* note: see note #13 above about the 258 in this list. */
196/* Extra bits for literal codes 257..285 */
197static const uint8_t cplext[] ALIGN1 = {
198 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 5,
199 5, 5, 5, 0, 99, 99
200}; /* 99 == invalid */
201
202/* Copy offsets for distance codes 0..29 */
203static const uint16_t cpdist[] ALIGN2 = {
204 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, 257, 385, 513,
205 769, 1025, 1537, 2049, 3073, 4097, 6145, 8193, 12289, 16385, 24577
206};
207
208/* Extra bits for distance codes */
209static const uint8_t cpdext[] ALIGN1 = {
210 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10,
211 11, 11, 12, 12, 13, 13
212};
213
214/* Tables for deflate from PKZIP's appnote.txt. */
215/* Order of the bit length code lengths */
216static const uint8_t border[] ALIGN1 = {
217 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15
218};
219
220
221/*
222 * Free the malloc'ed tables built by huft_build(), which makes a linked
223 * list of the tables it made, with the links in a dummy first entry of
224 * each table.
225 * t: table to free
226 */
227static void huft_free(huft_t *p)
228{
229 huft_t *q;
230
231 /* Go through linked list, freeing from the malloced (t[-1]) address. */
232 while (p) {
233 q = (--p)->v.t;
234 free(p);
235 p = q;
236 }
237}
238
239static void huft_free_all(STATE_PARAM_ONLY)
240{
241 huft_free(inflate_codes_tl);
242 huft_free(inflate_codes_td);
243 inflate_codes_tl = NULL;
244 inflate_codes_td = NULL;
245}
246
247static void abort_unzip(STATE_PARAM_ONLY) NORETURN;
248static void abort_unzip(STATE_PARAM_ONLY)
249{
250 huft_free_all(PASS_STATE_ONLY);
251 longjmp(error_jmp, 1);
252}
253
254static unsigned fill_bitbuffer(STATE_PARAM unsigned bitbuffer, unsigned *current, const unsigned required)
255{
256 while (*current < required) {
257 if (bytebuffer_offset >= bytebuffer_size) {
258 unsigned sz = bytebuffer_max - 4;
259 if (to_read >= 0 && to_read < sz) /* unzip only */
260 sz = to_read;
261 /* Leave the first 4 bytes empty so we can always unwind the bitbuffer
262 * to the front of the bytebuffer */
263 bytebuffer_size = safe_read(gunzip_src_fd, &bytebuffer[4], sz);
264 if ((int)bytebuffer_size < 1) {
265 error_msg = "unexpected end of file";
266 abort_unzip(PASS_STATE_ONLY);
267 }
268 if (to_read >= 0) /* unzip only */
269 to_read -= bytebuffer_size;
270 bytebuffer_size += 4;
271 bytebuffer_offset = 4;
272 }
273 bitbuffer |= ((unsigned) bytebuffer[bytebuffer_offset]) << *current;
274 bytebuffer_offset++;
275 *current += 8;
276 }
277 return bitbuffer;
278}
279
280
281/* Given a list of code lengths and a maximum table size, make a set of
282 * tables to decode that set of codes. Return zero on success, one if
283 * the given code set is incomplete (the tables are still built in this
284 * case), two if the input is invalid (all zero length codes or an
285 * oversubscribed set of lengths) - in this case stores NULL in *t.
286 *
287 * b: code lengths in bits (all assumed <= BMAX)
288 * n: number of codes (assumed <= N_MAX)
289 * s: number of simple-valued codes (0..s-1)
290 * d: list of base values for non-simple codes
291 * e: list of extra bits for non-simple codes
292 * t: result: starting table
293 * m: maximum lookup bits, returns actual
294 */
295static int huft_build(const unsigned *b, const unsigned n,
296 const unsigned s, const unsigned short *d,
297 const unsigned char *e, huft_t **t, unsigned *m)
298{
299 unsigned a; /* counter for codes of length k */
300 unsigned c[BMAX + 1]; /* bit length count table */
301 unsigned eob_len; /* length of end-of-block code (value 256) */
302 unsigned f; /* i repeats in table every f entries */
303 int g; /* maximum code length */
304 int htl; /* table level */
305 unsigned i; /* counter, current code */
306 unsigned j; /* counter */
307 int k; /* number of bits in current code */
308 unsigned *p; /* pointer into c[], b[], or v[] */
309 huft_t *q; /* points to current table */
310 huft_t r; /* table entry for structure assignment */
311 huft_t *u[BMAX]; /* table stack */
312 unsigned v[N_MAX]; /* values in order of bit length */
313 int ws[BMAX + 1]; /* bits decoded stack */
314 int w; /* bits decoded */
315 unsigned x[BMAX + 1]; /* bit offsets, then code stack */
316 unsigned *xp; /* pointer into x */
317 int y; /* number of dummy codes added */
318 unsigned z; /* number of entries in current table */
319
320 /* Length of EOB code, if any */
321 eob_len = n > 256 ? b[256] : BMAX;
322
323 *t = NULL;
324
325 /* Generate counts for each bit length */
326 memset(c, 0, sizeof(c));
327 p = (unsigned *) b; /* cast allows us to reuse p for pointing to b */
328 i = n;
329 do {
330 c[*p]++; /* assume all entries <= BMAX */
331 p++; /* can't combine with above line (Solaris bug) */
332 } while (--i);
333 if (c[0] == n) { /* null input - all zero length codes */
334 *m = 0;
335 return 2;
336 }
337
338 /* Find minimum and maximum length, bound *m by those */
339 for (j = 1; (c[j] == 0) && (j <= BMAX); j++)
340 continue;
341 k = j; /* minimum code length */
342 for (i = BMAX; (c[i] == 0) && i; i--)
343 continue;
344 g = i; /* maximum code length */
345 *m = (*m < j) ? j : ((*m > i) ? i : *m);
346
347 /* Adjust last length count to fill out codes, if needed */
348 for (y = 1 << j; j < i; j++, y <<= 1) {
349 y -= c[j];
350 if (y < 0)
351 return 2; /* bad input: more codes than bits */
352 }
353 y -= c[i];
354 if (y < 0)
355 return 2;
356 c[i] += y;
357
358 /* Generate starting offsets into the value table for each length */
359 x[1] = j = 0;
360 p = c + 1;
361 xp = x + 2;
362 while (--i) { /* note that i == g from above */
363 j += *p++;
364 *xp++ = j;
365 }
366
367 /* Make a table of values in order of bit lengths */
368 p = (unsigned *) b;
369 i = 0;
370 do {
371 j = *p++;
372 if (j != 0) {
373 v[x[j]++] = i;
374 }
375 } while (++i < n);
376
377 /* Generate the Huffman codes and for each, make the table entries */
378 x[0] = i = 0; /* first Huffman code is zero */
379 p = v; /* grab values in bit order */
380 htl = -1; /* no tables yet--level -1 */
381 w = ws[0] = 0; /* bits decoded */
382 u[0] = NULL; /* just to keep compilers happy */
383 q = NULL; /* ditto */
384 z = 0; /* ditto */
385
386 /* go through the bit lengths (k already is bits in shortest code) */
387 for (; k <= g; k++) {
388 a = c[k];
389 while (a--) {
390 /* here i is the Huffman code of length k bits for value *p */
391 /* make tables up to required level */
392 while (k > ws[htl + 1]) {
393 w = ws[++htl];
394
395 /* compute minimum size table less than or equal to *m bits */
396 z = g - w;
397 z = z > *m ? *m : z; /* upper limit on table size */
398 j = k - w;
399 f = 1 << j;
400 if (f > a + 1) { /* try a k-w bit table */
401 /* too few codes for k-w bit table */
402 f -= a + 1; /* deduct codes from patterns left */
403 xp = c + k;
404 while (++j < z) { /* try smaller tables up to z bits */
405 f <<= 1;
406 if (f <= *++xp) {
407 break; /* enough codes to use up j bits */
408 }
409 f -= *xp; /* else deduct codes from patterns */
410 }
411 }
412 j = (w + j > eob_len && w < eob_len) ? eob_len - w : j; /* make EOB code end at table */
413 z = 1 << j; /* table entries for j-bit table */
414 ws[htl+1] = w + j; /* set bits decoded in stack */
415
416 /* allocate and link in new table */
417 q = xzalloc((z + 1) * sizeof(huft_t));
418 *t = q + 1; /* link to list for huft_free() */
419 t = &(q->v.t);
420 u[htl] = ++q; /* table starts after link */
421
422 /* connect to last table, if there is one */
423 if (htl) {
424 x[htl] = i; /* save pattern for backing up */
425 r.b = (unsigned char) (w - ws[htl - 1]); /* bits to dump before this table */
426 r.e = (unsigned char) (16 + j); /* bits in this table */
427 r.v.t = q; /* pointer to this table */
428 j = (i & ((1 << w) - 1)) >> ws[htl - 1];
429 u[htl - 1][j] = r; /* connect to last table */
430 }
431 }
432
433 /* set up table entry in r */
434 r.b = (unsigned char) (k - w);
435 if (p >= v + n) {
436 r.e = 99; /* out of values--invalid code */
437 } else if (*p < s) {
438 r.e = (unsigned char) (*p < 256 ? 16 : 15); /* 256 is EOB code */
439 r.v.n = (unsigned short) (*p++); /* simple code is just the value */
440 } else {
441 r.e = (unsigned char) e[*p - s]; /* non-simple--look up in lists */
442 r.v.n = d[*p++ - s];
443 }
444
445 /* fill code-like entries with r */
446 f = 1 << (k - w);
447 for (j = i >> w; j < z; j += f) {
448 q[j] = r;
449 }
450
451 /* backwards increment the k-bit code i */
452 for (j = 1 << (k - 1); i & j; j >>= 1) {
453 i ^= j;
454 }
455 i ^= j;
456
457 /* backup over finished tables */
458 while ((i & ((1 << w) - 1)) != x[htl]) {
459 w = ws[--htl];
460 }
461 }
462 }
463
464 /* return actual size of base table */
465 *m = ws[1];
466
467 /* Return 1 if we were given an incomplete table */
468 return y != 0 && g != 1;
469}
470
471
472/*
473 * inflate (decompress) the codes in a deflated (compressed) block.
474 * Return an error code or zero if it all goes ok.
475 *
476 * tl, td: literal/length and distance decoder tables
477 * bl, bd: number of bits decoded by tl[] and td[]
478 */
479/* called once from inflate_block */
480
481/* map formerly local static variables to globals */
482#define ml inflate_codes_ml
483#define md inflate_codes_md
484#define bb inflate_codes_bb
485#define k inflate_codes_k
486#define w inflate_codes_w
487#define tl inflate_codes_tl
488#define td inflate_codes_td
489#define bl inflate_codes_bl
490#define bd inflate_codes_bd
491#define nn inflate_codes_nn
492#define dd inflate_codes_dd
493static void inflate_codes_setup(STATE_PARAM unsigned my_bl, unsigned my_bd)
494{
495 bl = my_bl;
496 bd = my_bd;
497 /* make local copies of globals */
498 bb = gunzip_bb; /* initialize bit buffer */
499 k = gunzip_bk;
500 w = gunzip_outbuf_count; /* initialize gunzip_window position */
501 /* inflate the coded data */
502 ml = mask_bits[bl]; /* precompute masks for speed */
503 md = mask_bits[bd];
504}
505/* called once from inflate_get_next_window */
506static NOINLINE int inflate_codes(STATE_PARAM_ONLY)
507{
508 unsigned e; /* table entry flag/number of extra bits */
509 huft_t *t; /* pointer to table entry */
510
511 if (resume_copy)
512 goto do_copy;
513
514 while (1) { /* do until end of block */
515 bb = fill_bitbuffer(PASS_STATE bb, &k, bl);
516 t = tl + ((unsigned) bb & ml);
517 e = t->e;
518 if (e > 16)
519 do {
520 if (e == 99)
521 abort_unzip(PASS_STATE_ONLY);;
522 bb >>= t->b;
523 k -= t->b;
524 e -= 16;
525 bb = fill_bitbuffer(PASS_STATE bb, &k, e);
526 t = t->v.t + ((unsigned) bb & mask_bits[e]);
527 e = t->e;
528 } while (e > 16);
529 bb >>= t->b;
530 k -= t->b;
531 if (e == 16) { /* then it's a literal */
532 gunzip_window[w++] = (unsigned char) t->v.n;
533 if (w == GUNZIP_WSIZE) {
534 gunzip_outbuf_count = w;
535 //flush_gunzip_window();
536 w = 0;
537 return 1; // We have a block to read
538 }
539 } else { /* it's an EOB or a length */
540 /* exit if end of block */
541 if (e == 15) {
542 break;
543 }
544
545 /* get length of block to copy */
546 bb = fill_bitbuffer(PASS_STATE bb, &k, e);
547 nn = t->v.n + ((unsigned) bb & mask_bits[e]);
548 bb >>= e;
549 k -= e;
550
551 /* decode distance of block to copy */
552 bb = fill_bitbuffer(PASS_STATE bb, &k, bd);
553 t = td + ((unsigned) bb & md);
554 e = t->e;
555 if (e > 16)
556 do {
557 if (e == 99)
558 abort_unzip(PASS_STATE_ONLY);
559 bb >>= t->b;
560 k -= t->b;
561 e -= 16;
562 bb = fill_bitbuffer(PASS_STATE bb, &k, e);
563 t = t->v.t + ((unsigned) bb & mask_bits[e]);
564 e = t->e;
565 } while (e > 16);
566 bb >>= t->b;
567 k -= t->b;
568 bb = fill_bitbuffer(PASS_STATE bb, &k, e);
569 dd = w - t->v.n - ((unsigned) bb & mask_bits[e]);
570 bb >>= e;
571 k -= e;
572
573 /* do the copy */
574 do_copy:
575 do {
576 /* Was: nn -= (e = (e = GUNZIP_WSIZE - ((dd &= GUNZIP_WSIZE - 1) > w ? dd : w)) > nn ? nn : e); */
577 /* Who wrote THAT?? rewritten as: */
578 unsigned delta;
579
580 dd &= GUNZIP_WSIZE - 1;
581 e = GUNZIP_WSIZE - (dd > w ? dd : w);
582 delta = w > dd ? w - dd : dd - w;
583 if (e > nn) e = nn;
584 nn -= e;
585
586 /* copy to new buffer to prevent possible overwrite */
587 if (delta >= e) {
588 memcpy(gunzip_window + w, gunzip_window + dd, e);
589 w += e;
590 dd += e;
591 } else {
592 /* do it slow to avoid memcpy() overlap */
593 /* !NOMEMCPY */
594 do {
595 gunzip_window[w++] = gunzip_window[dd++];
596 } while (--e);
597 }
598 if (w == GUNZIP_WSIZE) {
599 gunzip_outbuf_count = w;
600 resume_copy = (nn != 0);
601 //flush_gunzip_window();
602 w = 0;
603 return 1;
604 }
605 } while (nn);
606 resume_copy = 0;
607 }
608 }
609
610 /* restore the globals from the locals */
611 gunzip_outbuf_count = w; /* restore global gunzip_window pointer */
612 gunzip_bb = bb; /* restore global bit buffer */
613 gunzip_bk = k;
614
615 /* normally just after call to inflate_codes, but save code by putting it here */
616 /* free the decoding tables (tl and td), return */
617 huft_free_all(PASS_STATE_ONLY);
618
619 /* done */
620 return 0;
621}
622#undef ml
623#undef md
624#undef bb
625#undef k
626#undef w
627#undef tl
628#undef td
629#undef bl
630#undef bd
631#undef nn
632#undef dd
633
634
635/* called once from inflate_block */
636static void inflate_stored_setup(STATE_PARAM int my_n, int my_b, int my_k)
637{
638 inflate_stored_n = my_n;
639 inflate_stored_b = my_b;
640 inflate_stored_k = my_k;
641 /* initialize gunzip_window position */
642 inflate_stored_w = gunzip_outbuf_count;
643}
644/* called once from inflate_get_next_window */
645static int inflate_stored(STATE_PARAM_ONLY)
646{
647 /* read and output the compressed data */
648 while (inflate_stored_n--) {
649 inflate_stored_b = fill_bitbuffer(PASS_STATE inflate_stored_b, &inflate_stored_k, 8);
650 gunzip_window[inflate_stored_w++] = (unsigned char) inflate_stored_b;
651 if (inflate_stored_w == GUNZIP_WSIZE) {
652 gunzip_outbuf_count = inflate_stored_w;
653 //flush_gunzip_window();
654 inflate_stored_w = 0;
655 inflate_stored_b >>= 8;
656 inflate_stored_k -= 8;
657 return 1; /* We have a block */
658 }
659 inflate_stored_b >>= 8;
660 inflate_stored_k -= 8;
661 }
662
663 /* restore the globals from the locals */
664 gunzip_outbuf_count = inflate_stored_w; /* restore global gunzip_window pointer */
665 gunzip_bb = inflate_stored_b; /* restore global bit buffer */
666 gunzip_bk = inflate_stored_k;
667 return 0; /* Finished */
668}
669
670
671/*
672 * decompress an inflated block
673 * e: last block flag
674 *
675 * GLOBAL VARIABLES: bb, kk,
676 */
677/* Return values: -1 = inflate_stored, -2 = inflate_codes */
678/* One callsite in inflate_get_next_window */
679static int inflate_block(STATE_PARAM smallint *e)
680{
681 unsigned ll[286 + 30]; /* literal/length and distance code lengths */
682 unsigned t; /* block type */
683 unsigned b; /* bit buffer */
684 unsigned k; /* number of bits in bit buffer */
685
686 /* make local bit buffer */
687
688 b = gunzip_bb;
689 k = gunzip_bk;
690
691 /* read in last block bit */
692 b = fill_bitbuffer(PASS_STATE b, &k, 1);
693 *e = b & 1;
694 b >>= 1;
695 k -= 1;
696
697 /* read in block type */
698 b = fill_bitbuffer(PASS_STATE b, &k, 2);
699 t = (unsigned) b & 3;
700 b >>= 2;
701 k -= 2;
702
703 /* restore the global bit buffer */
704 gunzip_bb = b;
705 gunzip_bk = k;
706
707 /* Do we see block type 1 often? Yes!
708 * TODO: fix performance problem (see below) */
709 //bb_error_msg("blktype %d", t);
710
711 /* inflate that block type */
712 switch (t) {
713 case 0: /* Inflate stored */
714 {
715 unsigned n; /* number of bytes in block */
716 unsigned b_stored; /* bit buffer */
717 unsigned k_stored; /* number of bits in bit buffer */
718
719 /* make local copies of globals */
720 b_stored = gunzip_bb; /* initialize bit buffer */
721 k_stored = gunzip_bk;
722
723 /* go to byte boundary */
724 n = k_stored & 7;
725 b_stored >>= n;
726 k_stored -= n;
727
728 /* get the length and its complement */
729 b_stored = fill_bitbuffer(PASS_STATE b_stored, &k_stored, 16);
730 n = ((unsigned) b_stored & 0xffff);
731 b_stored >>= 16;
732 k_stored -= 16;
733
734 b_stored = fill_bitbuffer(PASS_STATE b_stored, &k_stored, 16);
735 if (n != (unsigned) ((~b_stored) & 0xffff)) {
736 abort_unzip(PASS_STATE_ONLY); /* error in compressed data */
737 }
738 b_stored >>= 16;
739 k_stored -= 16;
740
741 inflate_stored_setup(PASS_STATE n, b_stored, k_stored);
742
743 return -1;
744 }
745 case 1:
746 /* Inflate fixed
747 * decompress an inflated type 1 (fixed Huffman codes) block. We should
748 * either replace this with a custom decoder, or at least precompute the
749 * Huffman tables. TODO */
750 {
751 int i; /* temporary variable */
752 unsigned bl; /* lookup bits for tl */
753 unsigned bd; /* lookup bits for td */
754 /* gcc 4.2.1 is too dumb to reuse stackspace. Moved up... */
755 //unsigned ll[288]; /* length list for huft_build */
756
757 /* set up literal table */
758 for (i = 0; i < 144; i++)
759 ll[i] = 8;
760 for (; i < 256; i++)
761 ll[i] = 9;
762 for (; i < 280; i++)
763 ll[i] = 7;
764 for (; i < 288; i++) /* make a complete, but wrong code set */
765 ll[i] = 8;
766 bl = 7;
767 huft_build(ll, 288, 257, cplens, cplext, &inflate_codes_tl, &bl);
768 /* huft_build() never return nonzero - we use known data */
769
770 /* set up distance table */
771 for (i = 0; i < 30; i++) /* make an incomplete code set */
772 ll[i] = 5;
773 bd = 5;
774 huft_build(ll, 30, 0, cpdist, cpdext, &inflate_codes_td, &bd);
775
776 /* set up data for inflate_codes() */
777 inflate_codes_setup(PASS_STATE bl, bd);
778
779 /* huft_free code moved into inflate_codes */
780
781 return -2;
782 }
783 case 2: /* Inflate dynamic */
784 {
785 enum { dbits = 6 }; /* bits in base distance lookup table */
786 enum { lbits = 9 }; /* bits in base literal/length lookup table */
787
788 huft_t *td; /* distance code table */
789 unsigned i; /* temporary variables */
790 unsigned j;
791 unsigned l; /* last length */
792 unsigned m; /* mask for bit lengths table */
793 unsigned n; /* number of lengths to get */
794 unsigned bl; /* lookup bits for tl */
795 unsigned bd; /* lookup bits for td */
796 unsigned nb; /* number of bit length codes */
797 unsigned nl; /* number of literal/length codes */
798 unsigned nd; /* number of distance codes */
799
800 //unsigned ll[286 + 30];/* literal/length and distance code lengths */
801 unsigned b_dynamic; /* bit buffer */
802 unsigned k_dynamic; /* number of bits in bit buffer */
803
804 /* make local bit buffer */
805 b_dynamic = gunzip_bb;
806 k_dynamic = gunzip_bk;
807
808 /* read in table lengths */
809 b_dynamic = fill_bitbuffer(PASS_STATE b_dynamic, &k_dynamic, 5);
810 nl = 257 + ((unsigned) b_dynamic & 0x1f); /* number of literal/length codes */
811
812 b_dynamic >>= 5;
813 k_dynamic -= 5;
814 b_dynamic = fill_bitbuffer(PASS_STATE b_dynamic, &k_dynamic, 5);
815 nd = 1 + ((unsigned) b_dynamic & 0x1f); /* number of distance codes */
816
817 b_dynamic >>= 5;
818 k_dynamic -= 5;
819 b_dynamic = fill_bitbuffer(PASS_STATE b_dynamic, &k_dynamic, 4);
820 nb = 4 + ((unsigned) b_dynamic & 0xf); /* number of bit length codes */
821
822 b_dynamic >>= 4;
823 k_dynamic -= 4;
824 if (nl > 286 || nd > 30)
825 abort_unzip(PASS_STATE_ONLY); /* bad lengths */
826
827 /* read in bit-length-code lengths */
828 for (j = 0; j < nb; j++) {
829 b_dynamic = fill_bitbuffer(PASS_STATE b_dynamic, &k_dynamic, 3);
830 ll[border[j]] = (unsigned) b_dynamic & 7;
831 b_dynamic >>= 3;
832 k_dynamic -= 3;
833 }
834 for (; j < 19; j++)
835 ll[border[j]] = 0;
836
837 /* build decoding table for trees - single level, 7 bit lookup */
838 bl = 7;
839 i = huft_build(ll, 19, 19, NULL, NULL, &inflate_codes_tl, &bl);
840 if (i != 0) {
841 abort_unzip(PASS_STATE_ONLY); //return i; /* incomplete code set */
842 }
843
844 /* read in literal and distance code lengths */
845 n = nl + nd;
846 m = mask_bits[bl];
847 i = l = 0;
848 while ((unsigned) i < n) {
849 b_dynamic = fill_bitbuffer(PASS_STATE b_dynamic, &k_dynamic, (unsigned)bl);
850 td = inflate_codes_tl + ((unsigned) b_dynamic & m);
851 j = td->b;
852 b_dynamic >>= j;
853 k_dynamic -= j;
854 j = td->v.n;
855 if (j < 16) { /* length of code in bits (0..15) */
856 ll[i++] = l = j; /* save last length in l */
857 } else if (j == 16) { /* repeat last length 3 to 6 times */
858 b_dynamic = fill_bitbuffer(PASS_STATE b_dynamic, &k_dynamic, 2);
859 j = 3 + ((unsigned) b_dynamic & 3);
860 b_dynamic >>= 2;
861 k_dynamic -= 2;
862 if ((unsigned) i + j > n) {
863 abort_unzip(PASS_STATE_ONLY); //return 1;
864 }
865 while (j--) {
866 ll[i++] = l;
867 }
868 } else if (j == 17) { /* 3 to 10 zero length codes */
869 b_dynamic = fill_bitbuffer(PASS_STATE b_dynamic, &k_dynamic, 3);
870 j = 3 + ((unsigned) b_dynamic & 7);
871 b_dynamic >>= 3;
872 k_dynamic -= 3;
873 if ((unsigned) i + j > n) {
874 abort_unzip(PASS_STATE_ONLY); //return 1;
875 }
876 while (j--) {
877 ll[i++] = 0;
878 }
879 l = 0;
880 } else { /* j == 18: 11 to 138 zero length codes */
881 b_dynamic = fill_bitbuffer(PASS_STATE b_dynamic, &k_dynamic, 7);
882 j = 11 + ((unsigned) b_dynamic & 0x7f);
883 b_dynamic >>= 7;
884 k_dynamic -= 7;
885 if ((unsigned) i + j > n) {
886 abort_unzip(PASS_STATE_ONLY); //return 1;
887 }
888 while (j--) {
889 ll[i++] = 0;
890 }
891 l = 0;
892 }
893 }
894
895 /* free decoding table for trees */
896 huft_free(inflate_codes_tl);
897
898 /* restore the global bit buffer */
899 gunzip_bb = b_dynamic;
900 gunzip_bk = k_dynamic;
901
902 /* build the decoding tables for literal/length and distance codes */
903 bl = lbits;
904
905 i = huft_build(ll, nl, 257, cplens, cplext, &inflate_codes_tl, &bl);
906 if (i != 0)
907 abort_unzip(PASS_STATE_ONLY);
908 bd = dbits;
909 i = huft_build(ll + nl, nd, 0, cpdist, cpdext, &inflate_codes_td, &bd);
910 if (i != 0)
911 abort_unzip(PASS_STATE_ONLY);
912
913 /* set up data for inflate_codes() */
914 inflate_codes_setup(PASS_STATE bl, bd);
915
916 /* huft_free code moved into inflate_codes */
917
918 return -2;
919 }
920 default:
921 abort_unzip(PASS_STATE_ONLY);
922 }
923}
924
925/* Two callsites, both in inflate_get_next_window */
926static void calculate_gunzip_crc(STATE_PARAM_ONLY)
927{
928 gunzip_crc = crc32_block_endian0(gunzip_crc, gunzip_window, gunzip_outbuf_count, gunzip_crc_table);
929 gunzip_bytes_out += gunzip_outbuf_count;
930}
931
932/* One callsite in inflate_unzip_internal */
933static int inflate_get_next_window(STATE_PARAM_ONLY)
934{
935 gunzip_outbuf_count = 0;
936
937 while (1) {
938 int ret;
939
940 if (need_another_block) {
941 if (end_reached) {
942 calculate_gunzip_crc(PASS_STATE_ONLY);
943 end_reached = 0;
944 /* NB: need_another_block is still set */
945 return 0; /* Last block */
946 }
947 method = inflate_block(PASS_STATE &end_reached);
948 need_another_block = 0;
949 }
950
951 switch (method) {
952 case -1:
953 ret = inflate_stored(PASS_STATE_ONLY);
954 break;
955 case -2:
956 ret = inflate_codes(PASS_STATE_ONLY);
957 break;
958 default: /* cannot happen */
959 abort_unzip(PASS_STATE_ONLY);
960 }
961
962 if (ret == 1) {
963 calculate_gunzip_crc(PASS_STATE_ONLY);
964 return 1; /* more data left */
965 }
966 need_another_block = 1; /* end of that block */
967 }
968 /* Doesnt get here */
969}
970
971
972/* Called from unpack_gz_stream() and inflate_unzip() */
973static IF_DESKTOP(long long) int
974inflate_unzip_internal(STATE_PARAM int in, int out)
975{
976 IF_DESKTOP(long long) int n = 0;
977 ssize_t nwrote;
978
979 /* Allocate all global buffers (for DYN_ALLOC option) */
980 gunzip_window = xmalloc(GUNZIP_WSIZE);
981 gunzip_outbuf_count = 0;
982 gunzip_bytes_out = 0;
983 gunzip_src_fd = in;
984
985 /* (re) initialize state */
986 method = -1;
987 need_another_block = 1;
988 resume_copy = 0;
989 gunzip_bk = 0;
990 gunzip_bb = 0;
991
992 /* Create the crc table */
993 gunzip_crc_table = crc32_filltable(NULL, 0);
994 gunzip_crc = ~0;
995
996 error_msg = "corrupted data";
997 if (setjmp(error_jmp)) {
998 /* Error from deep inside zip machinery */
999 n = -1;
1000 goto ret;
1001 }
1002
1003 while (1) {
1004 int r = inflate_get_next_window(PASS_STATE_ONLY);
1005 nwrote = full_write(out, gunzip_window, gunzip_outbuf_count);
1006 if (nwrote != (ssize_t)gunzip_outbuf_count) {
1007 bb_perror_msg("write");
1008 n = -1;
1009 goto ret;
1010 }
1011 IF_DESKTOP(n += nwrote;)
1012 if (r == 0) break;
1013 }
1014
1015 /* Store unused bytes in a global buffer so calling applets can access it */
1016 if (gunzip_bk >= 8) {
1017 /* Undo too much lookahead. The next read will be byte aligned
1018 * so we can discard unused bits in the last meaningful byte. */
1019 bytebuffer_offset--;
1020 bytebuffer[bytebuffer_offset] = gunzip_bb & 0xff;
1021 gunzip_bb >>= 8;
1022 gunzip_bk -= 8;
1023 }
1024 ret:
1025 /* Cleanup */
1026 free(gunzip_window);
1027 free(gunzip_crc_table);
1028 return n;
1029}
1030
1031
1032/* External entry points */
1033
1034/* For unzip */
1035
1036IF_DESKTOP(long long) int FAST_FUNC
1037inflate_unzip(inflate_unzip_result *res, off_t compr_size, int in, int out)
1038{
1039 IF_DESKTOP(long long) int n;
1040 DECLARE_STATE;
1041
1042 ALLOC_STATE;
1043
1044 to_read = compr_size;
1045// bytebuffer_max = 0x8000;
1046 bytebuffer_offset = 4;
1047 bytebuffer = xmalloc(bytebuffer_max);
1048 n = inflate_unzip_internal(PASS_STATE in, out);
1049 free(bytebuffer);
1050
1051 res->crc = gunzip_crc;
1052 res->bytes_out = gunzip_bytes_out;
1053 DEALLOC_STATE;
1054 return n;
1055}
1056
1057
1058/* For gunzip */
1059
1060/* helpers first */
1061
1062/* Top up the input buffer with at least n bytes. */
1063static int top_up(STATE_PARAM unsigned n)
1064{
1065 int count = bytebuffer_size - bytebuffer_offset;
1066
1067 if (count < (int)n) {
1068 memmove(bytebuffer, &bytebuffer[bytebuffer_offset], count);
1069 bytebuffer_offset = 0;
1070 bytebuffer_size = full_read(gunzip_src_fd, &bytebuffer[count], bytebuffer_max - count);
1071 if ((int)bytebuffer_size < 0) {
1072 bb_error_msg(bb_msg_read_error);
1073 return 0;
1074 }
1075 bytebuffer_size += count;
1076 if (bytebuffer_size < n)
1077 return 0;
1078 }
1079 return 1;
1080}
1081
1082static uint16_t buffer_read_le_u16(STATE_PARAM_ONLY)
1083{
1084 uint16_t res;
1085#if BB_LITTLE_ENDIAN
1086 move_from_unaligned16(res, &bytebuffer[bytebuffer_offset]);
1087#else
1088 res = bytebuffer[bytebuffer_offset];
1089 res |= bytebuffer[bytebuffer_offset + 1] << 8;
1090#endif
1091 bytebuffer_offset += 2;
1092 return res;
1093}
1094
1095static uint32_t buffer_read_le_u32(STATE_PARAM_ONLY)
1096{
1097 uint32_t res;
1098#if BB_LITTLE_ENDIAN
1099 move_from_unaligned32(res, &bytebuffer[bytebuffer_offset]);
1100#else
1101 res = bytebuffer[bytebuffer_offset];
1102 res |= bytebuffer[bytebuffer_offset + 1] << 8;
1103 res |= bytebuffer[bytebuffer_offset + 2] << 16;
1104 res |= bytebuffer[bytebuffer_offset + 3] << 24;
1105#endif
1106 bytebuffer_offset += 4;
1107 return res;
1108}
1109
1110static int check_header_gzip(STATE_PARAM unpack_info_t *info)
1111{
1112 union {
1113 unsigned char raw[8];
1114 struct {
1115 uint8_t gz_method;
1116 uint8_t flags;
1117 uint32_t mtime;
1118 uint8_t xtra_flags_UNUSED;
1119 uint8_t os_flags_UNUSED;
1120 } PACKED formatted;
1121 } header;
1122 struct BUG_header {
1123 char BUG_header[sizeof(header) == 8 ? 1 : -1];
1124 };
1125
1126 /*
1127 * Rewind bytebuffer. We use the beginning because the header has 8
1128 * bytes, leaving enough for unwinding afterwards.
1129 */
1130 bytebuffer_size -= bytebuffer_offset;
1131 memmove(bytebuffer, &bytebuffer[bytebuffer_offset], bytebuffer_size);
1132 bytebuffer_offset = 0;
1133
1134 if (!top_up(PASS_STATE 8))
1135 return 0;
1136 memcpy(header.raw, &bytebuffer[bytebuffer_offset], 8);
1137 bytebuffer_offset += 8;
1138
1139 /* Check the compression method */
1140 if (header.formatted.gz_method != 8) {
1141 return 0;
1142 }
1143
1144 if (header.formatted.flags & 0x04) {
1145 /* bit 2 set: extra field present */
1146 unsigned extra_short;
1147
1148 if (!top_up(PASS_STATE 2))
1149 return 0;
1150 extra_short = buffer_read_le_u16(PASS_STATE_ONLY);
1151 if (!top_up(PASS_STATE extra_short))
1152 return 0;
1153 /* Ignore extra field */
1154 bytebuffer_offset += extra_short;
1155 }
1156
1157 /* Discard original name and file comment if any */
1158 /* bit 3 set: original file name present */
1159 /* bit 4 set: file comment present */
1160 if (header.formatted.flags & 0x18) {
1161 while (1) {
1162 do {
1163 if (!top_up(PASS_STATE 1))
1164 return 0;
1165 } while (bytebuffer[bytebuffer_offset++] != 0);
1166 if ((header.formatted.flags & 0x18) != 0x18)
1167 break;
1168 header.formatted.flags &= ~0x18;
1169 }
1170 }
1171
1172 if (info)
1173 info->mtime = SWAP_LE32(header.formatted.mtime);
1174
1175 /* Read the header checksum */
1176 if (header.formatted.flags & 0x02) {
1177 if (!top_up(PASS_STATE 2))
1178 return 0;
1179 bytebuffer_offset += 2;
1180 }
1181 return 1;
1182}
1183
1184IF_DESKTOP(long long) int FAST_FUNC
1185unpack_gz_stream_with_info(int in, int out, unpack_info_t *info)
1186{
1187 uint32_t v32;
1188 IF_DESKTOP(long long) int n;
1189 DECLARE_STATE;
1190
1191 n = 0;
1192
1193 ALLOC_STATE;
1194 to_read = -1;
1195// bytebuffer_max = 0x8000;
1196 bytebuffer = xmalloc(bytebuffer_max);
1197 gunzip_src_fd = in;
1198
1199 again:
1200 if (!check_header_gzip(PASS_STATE info)) {
1201 bb_error_msg("corrupted data");
1202 n = -1;
1203 goto ret;
1204 }
1205 n += inflate_unzip_internal(PASS_STATE in, out);
1206 if (n < 0)
1207 goto ret;
1208
1209 if (!top_up(PASS_STATE 8)) {
1210 bb_error_msg("corrupted data");
1211 n = -1;
1212 goto ret;
1213 }
1214
1215 /* Validate decompression - crc */
1216 v32 = buffer_read_le_u32(PASS_STATE_ONLY);
1217 if ((~gunzip_crc) != v32) {
1218 bb_error_msg("crc error");
1219 n = -1;
1220 goto ret;
1221 }
1222
1223 /* Validate decompression - size */
1224 v32 = buffer_read_le_u32(PASS_STATE_ONLY);
1225 if ((uint32_t)gunzip_bytes_out != v32) {
1226 bb_error_msg("incorrect length");
1227 n = -1;
1228 }
1229
1230 if (!top_up(PASS_STATE 2))
1231 goto ret; /* EOF */
1232
1233 if (bytebuffer[bytebuffer_offset] == 0x1f
1234 && bytebuffer[bytebuffer_offset + 1] == 0x8b
1235 ) {
1236 bytebuffer_offset += 2;
1237 goto again;
1238 }
1239 /* GNU gzip says: */
1240 /*bb_error_msg("decompression OK, trailing garbage ignored");*/
1241
1242 ret:
1243 free(bytebuffer);
1244 DEALLOC_STATE;
1245 return n;
1246}
1247
1248IF_DESKTOP(long long) int FAST_FUNC
1249unpack_gz_stream(int in, int out)
1250{
1251 return unpack_gz_stream_with_info(in, out, NULL);
1252}
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