ReactOS 0.4.15-dev-7674-gc0b4db1
lzx.c
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1/***************************************************************************
2 * lzx.c - LZX decompression routines *
3 * ------------------- *
4 * *
5 * maintainer: Jed Wing <jedwin@ugcs.caltech.edu> *
6 * source: modified lzx.c from cabextract v0.5 *
7 * notes: This file was taken from cabextract v0.5, which was, *
8 * itself, a modified version of the lzx decompression code *
9 * from unlzx. *
10 * *
11 * platforms: In its current incarnation, this file has been tested on *
12 * two different Linux platforms (one, redhat-based, with a *
13 * 2.1.2 glibc and gcc 2.95.x, and the other, Debian, with *
14 * 2.2.4 glibc and both gcc 2.95.4 and gcc 3.0.2). Both were *
15 * Intel x86 compatible machines. *
16 ***************************************************************************/
17
18/***************************************************************************
19 *
20 * Copyright(C) Stuart Caie
21 *
22 * This library is free software; you can redistribute it and/or
23 * modify it under the terms of the GNU Lesser General Public
24 * License as published by the Free Software Foundation; either
25 * version 2.1 of the License, or (at your option) any later version.
26 *
27 * This library is distributed in the hope that it will be useful,
28 * but WITHOUT ANY WARRANTY; without even the implied warranty of
29 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
30 * Lesser General Public License for more details.
31 *
32 * You should have received a copy of the GNU Lesser General Public
33 * License along with this library; if not, write to the Free Software
34 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
35 *
36 ***************************************************************************/
37
38#include "lzx.h"
39#include <stdarg.h>
40#include <stdio.h>
41#include <stdlib.h>
42#include <string.h>
43
44#include "windef.h"
45#include "winbase.h"
46
47/* sized types */
48typedef unsigned char UBYTE; /* 8 bits exactly */
49typedef unsigned short UWORD; /* 16 bits (or more) */
50
51/* some constants defined by the LZX specification */
52#define LZX_MIN_MATCH (2)
53#define LZX_MAX_MATCH (257)
54#define LZX_NUM_CHARS (256)
55#define LZX_BLOCKTYPE_INVALID (0) /* also blocktypes 4-7 invalid */
56#define LZX_BLOCKTYPE_VERBATIM (1)
57#define LZX_BLOCKTYPE_ALIGNED (2)
58#define LZX_BLOCKTYPE_UNCOMPRESSED (3)
59#define LZX_PRETREE_NUM_ELEMENTS (20)
60#define LZX_ALIGNED_NUM_ELEMENTS (8) /* aligned offset tree #elements */
61#define LZX_NUM_PRIMARY_LENGTHS (7) /* this one missing from spec! */
62#define LZX_NUM_SECONDARY_LENGTHS (249) /* length tree #elements */
63
64/* LZX huffman defines: tweak tablebits as desired */
65#define LZX_PRETREE_MAXSYMBOLS (LZX_PRETREE_NUM_ELEMENTS)
66#define LZX_PRETREE_TABLEBITS (6)
67#define LZX_MAINTREE_MAXSYMBOLS (LZX_NUM_CHARS + 50*8)
68#define LZX_MAINTREE_TABLEBITS (12)
69#define LZX_LENGTH_MAXSYMBOLS (LZX_NUM_SECONDARY_LENGTHS+1)
70#define LZX_LENGTH_TABLEBITS (12)
71#define LZX_ALIGNED_MAXSYMBOLS (LZX_ALIGNED_NUM_ELEMENTS)
72#define LZX_ALIGNED_TABLEBITS (7)
73
74#define LZX_LENTABLE_SAFETY (64) /* we allow length table decoding overruns */
75
76#define LZX_DECLARE_TABLE(tbl) \
77 UWORD tbl##_table[(1<<LZX_##tbl##_TABLEBITS) + (LZX_##tbl##_MAXSYMBOLS<<1)];\
78 UBYTE tbl##_len [LZX_##tbl##_MAXSYMBOLS + LZX_LENTABLE_SAFETY]
79
80struct LZXstate
81{
82 UBYTE *window; /* the actual decoding window */
83 ULONG window_size; /* window size (32Kb through 2Mb) */
84 ULONG actual_size; /* window size when it was first allocated */
85 ULONG window_posn; /* current offset within the window */
86 ULONG R0, R1, R2; /* for the LRU offset system */
87 UWORD main_elements; /* number of main tree elements */
88 int header_read; /* have we started decoding at all yet? */
89 UWORD block_type; /* type of this block */
90 ULONG block_length; /* uncompressed length of this block */
91 ULONG block_remaining; /* uncompressed bytes still left to decode */
92 ULONG frames_read; /* the number of CFDATA blocks processed */
93 LONG intel_filesize; /* magic header value used for transform */
94 LONG intel_curpos; /* current offset in transform space */
95 int intel_started; /* have we seen any translatable data yet? */
96
101};
102
103/* LZX decruncher */
104
105/* Microsoft's LZX document and their implementation of the
106 * com.ms.util.cab Java package do not concur.
107 *
108 * In the LZX document, there is a table showing the correlation between
109 * window size and the number of position slots. It states that the 1MB
110 * window = 40 slots and the 2MB window = 42 slots. In the implementation,
111 * 1MB = 42 slots, 2MB = 50 slots. The actual calculation is 'find the
112 * first slot whose position base is equal to or more than the required
113 * window size'. This would explain why other tables in the document refer
114 * to 50 slots rather than 42.
115 *
116 * The constant NUM_PRIMARY_LENGTHS used in the decompression pseudocode
117 * is not defined in the specification.
118 *
119 * The LZX document does not state the uncompressed block has an
120 * uncompressed length field. Where does this length field come from, so
121 * we can know how large the block is? The implementation has it as the 24
122 * bits following after the 3 blocktype bits, before the alignment
123 * padding.
124 *
125 * The LZX document states that aligned offset blocks have their aligned
126 * offset huffman tree AFTER the main and length trees. The implementation
127 * suggests that the aligned offset tree is BEFORE the main and length
128 * trees.
129 *
130 * The LZX document decoding algorithm states that, in an aligned offset
131 * block, if an extra_bits value is 1, 2 or 3, then that number of bits
132 * should be read and the result added to the match offset. This is
133 * correct for 1 and 2, but not 3, where just a huffman symbol (using the
134 * aligned tree) should be read.
135 *
136 * Regarding the E8 preprocessing, the LZX document states 'No translation
137 * may be performed on the last 6 bytes of the input block'. This is
138 * correct. However, the pseudocode provided checks for the *E8 leader*
139 * up to the last 6 bytes. If the leader appears between -10 and -7 bytes
140 * from the end, this would cause the next four bytes to be modified, at
141 * least one of which would be in the last 6 bytes, which is not allowed
142 * according to the spec.
143 *
144 * The specification states that the huffman trees must always contain at
145 * least one element. However, many CAB files contain blocks where the
146 * length tree is completely empty (because there are no matches), and
147 * this is expected to succeed.
148 */
149
150
151/* LZX uses what it calls 'position slots' to represent match offsets.
152 * What this means is that a small 'position slot' number and a small
153 * offset from that slot are encoded instead of one large offset for
154 * every match.
155 * - position_base is an index to the position slot bases
156 * - extra_bits states how many bits of offset-from-base data is needed.
157 */
158static const UBYTE extra_bits[51] = {
159 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
160 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13, 14, 14,
161 15, 15, 16, 16, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17,
162 17, 17, 17
163};
164
165static const ULONG position_base[51] = {
166 0, 1, 2, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
167 256, 384, 512, 768, 1024, 1536, 2048, 3072, 4096, 6144, 8192, 12288, 16384, 24576, 32768, 49152,
168 65536, 98304, 131072, 196608, 262144, 393216, 524288, 655360, 786432, 917504, 1048576, 1179648, 1310720, 1441792, 1572864, 1703936,
169 1835008, 1966080, 2097152
170};
171
173{
174 struct LZXstate *pState=NULL;
175 ULONG wndsize = 1 << window;
176 int i, posn_slots;
177
178 /* LZX supports window sizes of 2^15 (32Kb) through 2^21 (2Mb) */
179 /* if a previously allocated window is big enough, keep it */
180 if (window < 15 || window > 21) return NULL;
181
182 /* allocate state and associated window */
183 pState = HeapAlloc(GetProcessHeap(), 0, sizeof(struct LZXstate));
184 if (!(pState->window = HeapAlloc(GetProcessHeap(), 0, wndsize)))
185 {
186 HeapFree(GetProcessHeap(), 0, pState);
187 return NULL;
188 }
189 pState->actual_size = wndsize;
190 pState->window_size = wndsize;
191
192 /* calculate required position slots */
193 if (window == 20) posn_slots = 42;
194 else if (window == 21) posn_slots = 50;
195 else posn_slots = window << 1;
196
198 /* posn_slots=i=0; while (i < wndsize) i += 1 << extra_bits[posn_slots++]; */
199
200 /* initialize other state */
201 pState->R0 = pState->R1 = pState->R2 = 1;
202 pState->main_elements = LZX_NUM_CHARS + (posn_slots << 3);
203 pState->header_read = 0;
204 pState->frames_read = 0;
205 pState->block_remaining = 0;
207 pState->intel_curpos = 0;
208 pState->intel_started = 0;
209 pState->window_posn = 0;
210
211 /* initialise tables to 0 (because deltas will be applied to them) */
212 for (i = 0; i < LZX_MAINTREE_MAXSYMBOLS; i++) pState->MAINTREE_len[i] = 0;
213 for (i = 0; i < LZX_LENGTH_MAXSYMBOLS; i++) pState->LENGTH_len[i] = 0;
214
215 return pState;
216}
217
218void LZXteardown(struct LZXstate *pState)
219{
220 if (pState)
221 {
222 HeapFree(GetProcessHeap(), 0, pState->window);
223 HeapFree(GetProcessHeap(), 0, pState);
224 }
225}
226
227int LZXreset(struct LZXstate *pState)
228{
229 int i;
230
231 pState->R0 = pState->R1 = pState->R2 = 1;
232 pState->header_read = 0;
233 pState->frames_read = 0;
234 pState->block_remaining = 0;
236 pState->intel_curpos = 0;
237 pState->intel_started = 0;
238 pState->window_posn = 0;
239
240 for (i = 0; i < LZX_MAINTREE_MAXSYMBOLS + LZX_LENTABLE_SAFETY; i++) pState->MAINTREE_len[i] = 0;
241 for (i = 0; i < LZX_LENGTH_MAXSYMBOLS + LZX_LENTABLE_SAFETY; i++) pState->LENGTH_len[i] = 0;
242
243 return DECR_OK;
244}
245
246
247/* Bitstream reading macros:
248 *
249 * INIT_BITSTREAM should be used first to set up the system
250 * READ_BITS(var,n) takes N bits from the buffer and puts them in var
251 *
252 * ENSURE_BITS(n) ensures there are at least N bits in the bit buffer
253 * PEEK_BITS(n) extracts (without removing) N bits from the bit buffer
254 * REMOVE_BITS(n) removes N bits from the bit buffer
255 *
256 * These bit access routines work by using the area beyond the MSB and the
257 * LSB as a free source of zeroes. This avoids having to mask any bits.
258 * So we have to know the bit width of the bitbuffer variable. This is
259 * sizeof(ULONG) * 8, also defined as ULONG_BITS
260 */
261
262/* number of bits in ULONG. Note: This must be at multiple of 16, and at
263 * least 32 for the bitbuffer code to work (ie, it must be able to ensure
264 * up to 17 bits - that's adding 16 bits when there's one bit left, or
265 * adding 32 bits when there are no bits left. The code should work fine
266 * for machines where ULONG >= 32 bits.
267 */
268#define ULONG_BITS (sizeof(ULONG)<<3)
269
270#define INIT_BITSTREAM do { bitsleft = 0; bitbuf = 0; } while (0)
271
272#define ENSURE_BITS(n) \
273 while (bitsleft < (n)) { \
274 bitbuf |= ((inpos[1]<<8)|inpos[0]) << (ULONG_BITS-16 - bitsleft); \
275 bitsleft += 16; inpos+=2; \
276 }
277
278#define PEEK_BITS(n) (bitbuf >> (ULONG_BITS - (n)))
279#define REMOVE_BITS(n) ((bitbuf <<= (n)), (bitsleft -= (n)))
280
281#define READ_BITS(v,n) do { \
282 ENSURE_BITS(n); \
283 (v) = PEEK_BITS(n); \
284 REMOVE_BITS(n); \
285} while (0)
286
287
288/* Huffman macros */
289
290#define TABLEBITS(tbl) (LZX_##tbl##_TABLEBITS)
291#define MAXSYMBOLS(tbl) (LZX_##tbl##_MAXSYMBOLS)
292#define SYMTABLE(tbl) (pState->tbl##_table)
293#define LENTABLE(tbl) (pState->tbl##_len)
294
295/* BUILD_TABLE(tablename) builds a huffman lookup table from code lengths.
296 * In reality, it just calls make_decode_table() with the appropriate
297 * values - they're all fixed by some #defines anyway, so there's no point
298 * writing each call out in full by hand.
299 */
300#define BUILD_TABLE(tbl) \
301 if (make_decode_table( \
302 MAXSYMBOLS(tbl), TABLEBITS(tbl), LENTABLE(tbl), SYMTABLE(tbl) \
303 )) { return DECR_ILLEGALDATA; }
304
305
306/* READ_HUFFSYM(tablename, var) decodes one huffman symbol from the
307 * bitstream using the stated table and puts it in var.
308 */
309#define READ_HUFFSYM(tbl,var) do { \
310 ENSURE_BITS(16); \
311 hufftbl = SYMTABLE(tbl); \
312 if ((i = hufftbl[PEEK_BITS(TABLEBITS(tbl))]) >= MAXSYMBOLS(tbl)) { \
313 j = 1 << (ULONG_BITS - TABLEBITS(tbl)); \
314 do { \
315 j >>= 1; i <<= 1; i |= (bitbuf & j) ? 1 : 0; \
316 if (!j) { return DECR_ILLEGALDATA; } \
317 } while ((i = hufftbl[i]) >= MAXSYMBOLS(tbl)); \
318 } \
319 j = LENTABLE(tbl)[(var) = i]; \
320 REMOVE_BITS(j); \
321} while (0)
322
323
324/* READ_LENGTHS(tablename, first, last) reads in code lengths for symbols
325 * first to last in the given table. The code lengths are stored in their
326 * own special LZX way.
327 */
328#define READ_LENGTHS(tbl,first,last) do { \
329 lb.bb = bitbuf; lb.bl = bitsleft; lb.ip = inpos; \
330 if (lzx_read_lens(pState, LENTABLE(tbl),(first),(last),&lb)) { \
331 return DECR_ILLEGALDATA; \
332 } \
333 bitbuf = lb.bb; bitsleft = lb.bl; inpos = lb.ip; \
334} while (0)
335
336
337/* make_decode_table(nsyms, nbits, length[], table[])
338 *
339 * This function was coded by David Tritscher. It builds a fast huffman
340 * decoding table out of just a canonical huffman code lengths table.
341 *
342 * nsyms = total number of symbols in this huffman tree.
343 * nbits = any symbols with a code length of nbits or less can be decoded
344 * in one lookup of the table.
345 * length = A table to get code lengths from [0 to syms-1]
346 * table = The table to fill up with decoded symbols and pointers.
347 *
348 * Returns 0 for OK or 1 for error
349 */
350
351static int make_decode_table(ULONG nsyms, ULONG nbits, UBYTE *length, UWORD *table) {
352 register UWORD sym;
353 register ULONG leaf;
354 register UBYTE bit_num = 1;
355 ULONG fill;
356 ULONG pos = 0; /* the current position in the decode table */
357 ULONG table_mask = 1 << nbits;
358 ULONG bit_mask = table_mask >> 1; /* don't do 0 length codes */
359 ULONG next_symbol = bit_mask; /* base of allocation for long codes */
360
361 /* fill entries for codes short enough for a direct mapping */
362 while (bit_num <= nbits) {
363 for (sym = 0; sym < nsyms; sym++) {
364 if (length[sym] == bit_num) {
365 leaf = pos;
366
367 if((pos += bit_mask) > table_mask) return 1; /* table overrun */
368
369 /* fill all possible lookups of this symbol with the symbol itself */
370 fill = bit_mask;
371 while (fill-- > 0) table[leaf++] = sym;
372 }
373 }
374 bit_mask >>= 1;
375 bit_num++;
376 }
377
378 /* if there are any codes longer than nbits */
379 if (pos != table_mask) {
380 /* clear the remainder of the table */
381 for (sym = pos; sym < table_mask; sym++) table[sym] = 0;
382
383 /* give ourselves room for codes to grow by up to 16 more bits */
384 pos <<= 16;
385 table_mask <<= 16;
386 bit_mask = 1 << 15;
387
388 while (bit_num <= 16) {
389 for (sym = 0; sym < nsyms; sym++) {
390 if (length[sym] == bit_num) {
391 leaf = pos >> 16;
392 for (fill = 0; fill < bit_num - nbits; fill++) {
393 /* if this path hasn't been taken yet, 'allocate' two entries */
394 if (table[leaf] == 0) {
395 table[(next_symbol << 1)] = 0;
396 table[(next_symbol << 1) + 1] = 0;
397 table[leaf] = next_symbol++;
398 }
399 /* follow the path and select either left or right for next bit */
400 leaf = table[leaf] << 1;
401 if ((pos >> (15-fill)) & 1) leaf++;
402 }
403 table[leaf] = sym;
404
405 if ((pos += bit_mask) > table_mask) return 1; /* table overflow */
406 }
407 }
408 bit_mask >>= 1;
409 bit_num++;
410 }
411 }
412
413 /* full table? */
414 if (pos == table_mask) return 0;
415
416 /* either erroneous table, or all elements are 0 - let's find out. */
417 for (sym = 0; sym < nsyms; sym++) if (length[sym]) return 1;
418 return 0;
419}
420
421struct lzx_bits {
422 ULONG bb;
423 int bl;
424 UBYTE *ip;
425};
426
427static int lzx_read_lens(struct LZXstate *pState, UBYTE *lens, ULONG first, ULONG last, struct lzx_bits *lb) {
428 ULONG i,j, x,y;
429 int z;
430
431 register ULONG bitbuf = lb->bb;
432 register int bitsleft = lb->bl;
433 UBYTE *inpos = lb->ip;
434 UWORD *hufftbl;
435
436 for (x = 0; x < 20; x++) {
437 READ_BITS(y, 4);
438 LENTABLE(PRETREE)[x] = y;
439 }
440 BUILD_TABLE(PRETREE);
441
442 for (x = first; x < last; ) {
443 READ_HUFFSYM(PRETREE, z);
444 if (z == 17) {
445 READ_BITS(y, 4); y += 4;
446 while (y--) lens[x++] = 0;
447 }
448 else if (z == 18) {
449 READ_BITS(y, 5); y += 20;
450 while (y--) lens[x++] = 0;
451 }
452 else if (z == 19) {
453 READ_BITS(y, 1); y += 4;
454 READ_HUFFSYM(PRETREE, z);
455 z = lens[x] - z; if (z < 0) z += 17;
456 while (y--) lens[x++] = z;
457 }
458 else {
459 z = lens[x] - z; if (z < 0) z += 17;
460 lens[x++] = z;
461 }
462 }
463
464 lb->bb = bitbuf;
465 lb->bl = bitsleft;
466 lb->ip = inpos;
467 return 0;
468}
469
470int LZXdecompress(struct LZXstate *pState, unsigned char *inpos, unsigned char *outpos, int inlen, int outlen) {
471 UBYTE *endinp = inpos + inlen;
472 UBYTE *window = pState->window;
473 UBYTE *runsrc, *rundest;
474 UWORD *hufftbl; /* used in READ_HUFFSYM macro as chosen decoding table */
475
476 ULONG window_posn = pState->window_posn;
477 ULONG window_size = pState->window_size;
478 ULONG R0 = pState->R0;
479 ULONG R1 = pState->R1;
480 ULONG R2 = pState->R2;
481
482 register ULONG bitbuf;
483 register int bitsleft;
484 ULONG match_offset, i,j,k; /* ijk used in READ_HUFFSYM macro */
485 struct lzx_bits lb; /* used in READ_LENGTHS macro */
486
487 int togo = outlen, this_run, main_element, aligned_bits;
488 int match_length, length_footer, extra, verbatim_bits;
489 int copy_length;
490
492
493 /* read header if necessary */
494 if (!pState->header_read) {
495 i = j = 0;
496 READ_BITS(k, 1); if (k) { READ_BITS(i,16); READ_BITS(j,16); }
497 pState->intel_filesize = (i << 16) | j; /* or 0 if not encoded */
498 pState->header_read = 1;
499 }
500
501 /* main decoding loop */
502 while (togo > 0) {
503 /* last block finished, new block expected */
504 if (pState->block_remaining == 0) {
505 if (pState->block_type == LZX_BLOCKTYPE_UNCOMPRESSED) {
506 if (pState->block_length & 1) inpos++; /* realign bitstream to word */
508 }
509
510 READ_BITS(pState->block_type, 3);
511 READ_BITS(i, 16);
512 READ_BITS(j, 8);
513 pState->block_remaining = pState->block_length = (i << 8) | j;
514
515 switch (pState->block_type) {
517 for (i = 0; i < 8; i++) { READ_BITS(j, 3); LENTABLE(ALIGNED)[i] = j; }
519 /* rest of aligned header is same as verbatim */
520
522 READ_LENGTHS(MAINTREE, 0, 256);
523 READ_LENGTHS(MAINTREE, 256, pState->main_elements);
524 BUILD_TABLE(MAINTREE);
525 if (LENTABLE(MAINTREE)[0xE8] != 0) pState->intel_started = 1;
526
529 break;
530
532 pState->intel_started = 1; /* because we can't assume otherwise */
533 ENSURE_BITS(16); /* get up to 16 pad bits into the buffer */
534 if (bitsleft > 16) inpos -= 2; /* and align the bitstream! */
535 R0 = inpos[0]|(inpos[1]<<8)|(inpos[2]<<16)|(inpos[3]<<24);inpos+=4;
536 R1 = inpos[0]|(inpos[1]<<8)|(inpos[2]<<16)|(inpos[3]<<24);inpos+=4;
537 R2 = inpos[0]|(inpos[1]<<8)|(inpos[2]<<16)|(inpos[3]<<24);inpos+=4;
538 break;
539
540 default:
541 return DECR_ILLEGALDATA;
542 }
543 }
544
545 /* buffer exhaustion check */
546 if (inpos > endinp) {
547 /* it's possible to have a file where the next run is less than
548 * 16 bits in size. In this case, the READ_HUFFSYM() macro used
549 * in building the tables will exhaust the buffer, so we should
550 * allow for this, but not allow those accidentally read bits to
551 * be used (so we check that there are at least 16 bits
552 * remaining - in this boundary case they aren't really part of
553 * the compressed data)
554 */
555 if (inpos > (endinp+2) || bitsleft < 16) return DECR_ILLEGALDATA;
556 }
557
558 while ((this_run = pState->block_remaining) > 0 && togo > 0) {
559 if (this_run > togo) this_run = togo;
560 togo -= this_run;
561 pState->block_remaining -= this_run;
562
563 /* apply 2^x-1 mask */
564 window_posn &= window_size - 1;
565 /* runs can't straddle the window wraparound */
566 if ((window_posn + this_run) > window_size)
567 return DECR_DATAFORMAT;
568
569 switch (pState->block_type) {
570
572 while (this_run > 0) {
573 READ_HUFFSYM(MAINTREE, main_element);
574
575 if (main_element < LZX_NUM_CHARS) {
576 /* literal: 0 to LZX_NUM_CHARS-1 */
577 window[window_posn++] = main_element;
578 this_run--;
579 }
580 else {
581 /* match: LZX_NUM_CHARS + ((slot<<3) | length_header (3 bits)) */
582 main_element -= LZX_NUM_CHARS;
583
584 match_length = main_element & LZX_NUM_PRIMARY_LENGTHS;
585 if (match_length == LZX_NUM_PRIMARY_LENGTHS) {
586 READ_HUFFSYM(LENGTH, length_footer);
587 match_length += length_footer;
588 }
589 match_length += LZX_MIN_MATCH;
590
591 match_offset = main_element >> 3;
592
593 if (match_offset > 2) {
594 /* not repeated offset */
595 if (match_offset != 3) {
596 extra = extra_bits[match_offset];
597 READ_BITS(verbatim_bits, extra);
598 match_offset = position_base[match_offset] - 2 + verbatim_bits;
599 }
600 else {
601 match_offset = 1;
602 }
603
604 /* update repeated offset LRU queue */
605 R2 = R1; R1 = R0; R0 = match_offset;
606 }
607 else if (match_offset == 0) {
608 match_offset = R0;
609 }
610 else if (match_offset == 1) {
611 match_offset = R1;
612 R1 = R0; R0 = match_offset;
613 }
614 else /* match_offset == 2 */ {
615 match_offset = R2;
616 R2 = R0; R0 = match_offset;
617 }
618
619 rundest = window + window_posn;
620 this_run -= match_length;
621
622 /* copy any wrapped around source data */
623 if (window_posn >= match_offset) {
624 /* no wrap */
625 runsrc = rundest - match_offset;
626 } else {
627 runsrc = rundest + (window_size - match_offset);
628 copy_length = match_offset - window_posn;
629 if (copy_length < match_length) {
630 match_length -= copy_length;
631 window_posn += copy_length;
632 while (copy_length-- > 0) *rundest++ = *runsrc++;
633 runsrc = window;
634 }
635 }
636 window_posn += match_length;
637
638 /* copy match data - no worries about destination wraps */
639 while (match_length-- > 0) *rundest++ = *runsrc++;
640
641 }
642 }
643 break;
644
646 while (this_run > 0) {
647 READ_HUFFSYM(MAINTREE, main_element);
648
649 if (main_element < LZX_NUM_CHARS) {
650 /* literal: 0 to LZX_NUM_CHARS-1 */
651 window[window_posn++] = main_element;
652 this_run--;
653 }
654 else {
655 /* match: LZX_NUM_CHARS + ((slot<<3) | length_header (3 bits)) */
656 main_element -= LZX_NUM_CHARS;
657
658 match_length = main_element & LZX_NUM_PRIMARY_LENGTHS;
659 if (match_length == LZX_NUM_PRIMARY_LENGTHS) {
660 READ_HUFFSYM(LENGTH, length_footer);
661 match_length += length_footer;
662 }
663 match_length += LZX_MIN_MATCH;
664
665 match_offset = main_element >> 3;
666
667 if (match_offset > 2) {
668 /* not repeated offset */
669 extra = extra_bits[match_offset];
670 match_offset = position_base[match_offset] - 2;
671 if (extra > 3) {
672 /* verbatim and aligned bits */
673 extra -= 3;
674 READ_BITS(verbatim_bits, extra);
675 match_offset += (verbatim_bits << 3);
676 READ_HUFFSYM(ALIGNED, aligned_bits);
677 match_offset += aligned_bits;
678 }
679 else if (extra == 3) {
680 /* aligned bits only */
681 READ_HUFFSYM(ALIGNED, aligned_bits);
682 match_offset += aligned_bits;
683 }
684 else if (extra > 0) { /* extra==1, extra==2 */
685 /* verbatim bits only */
686 READ_BITS(verbatim_bits, extra);
687 match_offset += verbatim_bits;
688 }
689 else /* extra == 0 */ {
690 /* ??? */
691 match_offset = 1;
692 }
693
694 /* update repeated offset LRU queue */
695 R2 = R1; R1 = R0; R0 = match_offset;
696 }
697 else if (match_offset == 0) {
698 match_offset = R0;
699 }
700 else if (match_offset == 1) {
701 match_offset = R1;
702 R1 = R0; R0 = match_offset;
703 }
704 else /* match_offset == 2 */ {
705 match_offset = R2;
706 R2 = R0; R0 = match_offset;
707 }
708
709 rundest = window + window_posn;
710 this_run -= match_length;
711
712 /* copy any wrapped around source data */
713 if (window_posn >= match_offset) {
714 /* no wrap */
715 runsrc = rundest - match_offset;
716 } else {
717 runsrc = rundest + (window_size - match_offset);
718 copy_length = match_offset - window_posn;
719 if (copy_length < match_length) {
720 match_length -= copy_length;
721 window_posn += copy_length;
722 while (copy_length-- > 0) *rundest++ = *runsrc++;
723 runsrc = window;
724 }
725 }
726 window_posn += match_length;
727
728 /* copy match data - no worries about destination wraps */
729 while (match_length-- > 0) *rundest++ = *runsrc++;
730
731 }
732 }
733 break;
734
736 if ((inpos + this_run) > endinp) return DECR_ILLEGALDATA;
737 memcpy(window + window_posn, inpos, (size_t) this_run);
738 inpos += this_run; window_posn += this_run;
739 break;
740
741 default:
742 return DECR_ILLEGALDATA; /* might as well */
743 }
744
745 }
746 }
747
748 if (togo != 0) return DECR_ILLEGALDATA;
749 memcpy(outpos, window + ((!window_posn) ? window_size : window_posn) - outlen, (size_t) outlen);
750
751 pState->window_posn = window_posn;
752 pState->R0 = R0;
753 pState->R1 = R1;
754 pState->R2 = R2;
755
756 /* intel E8 decoding */
757 if ((pState->frames_read++ < 32768) && pState->intel_filesize != 0) {
758 if (outlen <= 6 || !pState->intel_started) {
759 pState->intel_curpos += outlen;
760 }
761 else {
762 UBYTE *data = outpos;
763 UBYTE *dataend = data + outlen - 10;
764 LONG curpos = pState->intel_curpos;
765 LONG filesize = pState->intel_filesize;
766 LONG abs_off, rel_off;
767
768 pState->intel_curpos = curpos + outlen;
769
770 while (data < dataend) {
771 if (*data++ != 0xE8) { curpos++; continue; }
772 abs_off = data[0] | (data[1]<<8) | (data[2]<<16) | (data[3]<<24);
773 if ((abs_off >= -curpos) && (abs_off < filesize)) {
774 rel_off = (abs_off >= 0) ? abs_off - curpos : abs_off + filesize;
775 data[0] = (UBYTE) rel_off;
776 data[1] = (UBYTE) (rel_off >> 8);
777 data[2] = (UBYTE) (rel_off >> 16);
778 data[3] = (UBYTE) (rel_off >> 24);
779 }
780 data += 4;
781 curpos += 5;
782 }
783 }
784 }
785 return DECR_OK;
786}
787
788#ifdef LZX_CHM_TESTDRIVER
789int main(int c, char **v)
790{
791 FILE *fin, *fout;
792 struct LZXstate state;
793 UBYTE ibuf[16384];
794 UBYTE obuf[32768];
795 int ilen, olen;
796 int status;
797 int i;
798 int count=0;
799 int w = atoi(v[1]);
800 LZXinit(&state, w);
801 fout = fopen(v[2], "wb");
802 for (i=3; i<c; i++)
803 {
804 fin = fopen(v[i], "rb");
805 ilen = fread(ibuf, 1, 16384, fin);
806 status = LZXdecompress(&state, ibuf, obuf, ilen, 32768);
807 switch (status)
808 {
809 case DECR_OK:
810 printf("ok\n");
811 fwrite(obuf, 1, 32768, fout);
812 break;
813 case DECR_DATAFORMAT:
814 printf("bad format\n");
815 break;
816 case DECR_ILLEGALDATA:
817 printf("illegal data\n");
818 break;
819 case DECR_NOMEMORY:
820 printf("no memory\n");
821 break;
822 default:
823 break;
824 }
825 fclose(fin);
826 if (++count == 2)
827 {
828 count = 0;
829 LZXreset(&state);
830 }
831 }
832 fclose(fout);
833}
834#endif
_STLP_MOVE_TO_STD_NAMESPACE void fill(_ForwardIter __first, _ForwardIter __last, const _Tp &__val)
Definition: _algobase.h:449
static int state
Definition: maze.c:121
#define NULL
Definition: types.h:112
#define DECR_OK
Definition: mszip.h:79
#define DECR_ILLEGALDATA
Definition: mszip.h:81
#define DECR_DATAFORMAT
Definition: mszip.h:80
#define DECR_NOMEMORY
Definition: mszip.h:82
#define GetProcessHeap()
Definition: compat.h:736
#define HeapAlloc
Definition: compat.h:733
#define HeapFree(x, y, z)
Definition: compat.h:735
@ LENGTH
Definition: inflate.c:185
int main()
Definition: test.c:6
#define printf
Definition: freeldr.h:94
GLint GLint GLint GLint GLint x
Definition: gl.h:1548
const GLdouble * v
Definition: gl.h:2040
GLint GLint GLint GLint GLint GLint y
Definition: gl.h:1548
GLuint GLuint GLsizei count
Definition: gl.h:1545
GLint GLenum GLsizei GLsizei GLsizei GLint GLsizei const GLvoid * data
Definition: gl.h:1950
const GLubyte * c
Definition: glext.h:8905
GLuint GLsizei GLsizei * length
Definition: glext.h:6040
const GLint * first
Definition: glext.h:5794
GLubyte GLubyte GLubyte GLubyte w
Definition: glext.h:6102
GLdouble GLdouble z
Definition: glext.h:5874
GLsizei GLenum const GLvoid GLsizei GLenum GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLint GLint GLint GLshort GLshort GLshort GLubyte GLubyte GLubyte GLuint GLuint GLuint GLushort GLushort GLushort GLbyte GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLfloat GLint GLint GLint GLint GLshort GLshort GLshort GLshort GLubyte GLubyte GLubyte GLubyte GLuint GLuint GLuint GLuint GLushort GLushort GLushort GLushort GLboolean const GLdouble const GLfloat const GLint const GLshort const GLbyte const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLdouble const GLfloat const GLfloat const GLint const GLint const GLshort const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort GLenum GLenum GLenum GLfloat GLenum GLint GLenum GLenum GLenum GLfloat GLenum GLenum GLint GLenum GLfloat GLenum GLint GLint GLushort GLenum GLenum GLfloat GLenum GLenum GLint GLfloat const GLubyte GLenum GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLint GLint GLsizei GLsizei GLint GLenum GLenum const GLvoid GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLenum const GLdouble GLenum GLenum const GLfloat GLenum GLenum const GLint GLsizei GLuint GLfloat GLuint GLbitfield GLfloat GLint GLuint GLboolean GLenum GLfloat GLenum GLbitfield GLenum GLfloat GLfloat GLint GLint const GLfloat GLenum GLfloat GLfloat GLint GLint GLfloat GLfloat GLint GLint const GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat const GLdouble const GLfloat const GLdouble const GLfloat GLint i
Definition: glfuncs.h:248
GLsizei GLenum const GLvoid GLsizei GLenum GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLint GLint GLint GLshort GLshort GLshort GLubyte GLubyte GLubyte GLuint GLuint GLuint GLushort GLushort GLushort GLbyte GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLfloat GLint GLint GLint GLint GLshort GLshort GLshort GLshort GLubyte GLubyte GLubyte GLubyte GLuint GLuint GLuint GLuint GLushort GLushort GLushort GLushort GLboolean const GLdouble const GLfloat const GLint const GLshort const GLbyte const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLdouble const GLfloat const GLfloat const GLint const GLint const GLshort const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort GLenum GLenum GLenum GLfloat GLenum GLint GLenum GLenum GLenum GLfloat GLenum GLenum GLint GLenum GLfloat GLenum GLint GLint GLushort GLenum GLenum GLfloat GLenum GLenum GLint GLfloat const GLubyte GLenum GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLint GLint GLsizei GLsizei GLint GLenum GLenum const GLvoid GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLenum const GLdouble GLenum GLenum const GLfloat GLenum GLenum const GLint GLsizei GLuint GLfloat GLuint GLbitfield GLfloat GLint GLuint GLboolean GLenum GLfloat GLenum GLbitfield GLenum GLfloat GLfloat GLint GLint const GLfloat GLenum GLfloat GLfloat GLint GLint GLfloat GLfloat GLint GLint const GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat const GLdouble const GLfloat const GLdouble const GLfloat GLint GLint GLint j
Definition: glfuncs.h:250
static char obuf[100]
Definition: i386-dis.c:1281
@ extra
Definition: id3.c:95
_Check_return_opt_ _CRTIMP size_t __cdecl fread(_Out_writes_bytes_(_ElementSize *_Count) void *_DstBuf, _In_ size_t _ElementSize, _In_ size_t _Count, _Inout_ FILE *_File)
_Check_return_ _CRTIMP FILE *__cdecl fopen(_In_z_ const char *_Filename, _In_z_ const char *_Mode)
_Check_return_opt_ _CRTIMP int __cdecl fclose(_Inout_ FILE *_File)
_Check_return_opt_ _CRTIMP size_t __cdecl fwrite(_In_reads_bytes_(_Size *_Count) const void *_Str, _In_ size_t _Size, _In_ size_t _Count, _Inout_ FILE *_File)
_Check_return_ int __cdecl atoi(_In_z_ const char *_Str)
void LZXteardown(struct LZXstate *pState)
Definition: lzx.c:209
#define LZX_NUM_CHARS
Definition: lzx.c:54
unsigned char UBYTE
Definition: lzx.c:48
int LZXdecompress(struct LZXstate *pState, unsigned char *inpos, unsigned char *outpos, int inlen, int outlen)
Definition: lzx.c:461
#define LZX_BLOCKTYPE_INVALID
Definition: lzx.c:55
#define READ_LENGTHS(tbl, first, last)
Definition: lzx.c:319
#define LZX_MAINTREE_MAXSYMBOLS
Definition: lzx.c:67
#define LZX_BLOCKTYPE_ALIGNED
Definition: lzx.c:57
#define LZX_NUM_SECONDARY_LENGTHS
Definition: lzx.c:62
#define READ_BITS(v, n)
Definition: lzx.c:272
#define LENTABLE(tbl)
Definition: lzx.c:284
#define LZX_BLOCKTYPE_VERBATIM
Definition: lzx.c:56
#define LZX_LENGTH_MAXSYMBOLS
Definition: lzx.c:69
#define LZX_NUM_PRIMARY_LENGTHS
Definition: lzx.c:61
#define READ_HUFFSYM(tbl, var)
Definition: lzx.c:300
#define LZX_BLOCKTYPE_UNCOMPRESSED
Definition: lzx.c:58
static const ULONG position_base[51]
Definition: lzx.c:165
struct LZXstate * LZXinit(int wndsize)
Definition: lzx.c:172
static int make_decode_table(ULONG nsyms, ULONG nbits, UBYTE *length, UWORD *table)
Definition: lzx.c:342
int LZXreset(struct LZXstate *pState)
Definition: lzx.c:218
#define INIT_BITSTREAM
Definition: lzx.c:261
#define BUILD_TABLE(tbl)
Definition: lzx.c:291
static int lzx_read_lens(struct LZXstate *pState, UBYTE *lens, ULONG first, ULONG last, struct lzx_bits *lb)
Definition: lzx.c:418
#define LZX_LENTABLE_SAFETY
Definition: lzx.c:74
unsigned short UWORD
Definition: lzx.c:49
#define LZX_MIN_MATCH
Definition: lzx.c:52
#define ENSURE_BITS(n)
Definition: lzx.c:263
static const UBYTE extra_bits[51]
Definition: lzx.c:158
#define c
Definition: ke_i.h:80
#define memcpy(s1, s2, n)
Definition: mkisofs.h:878
#define for
Definition: utility.h:88
static UINT UINT last
Definition: font.c:45
static IHTMLWindow2 * window
Definition: events.c:77
int k
Definition: mpi.c:3369
#define ALIGNED(a)
Definition: optimize.h:190
long LONG
Definition: pedump.c:60
#define R1(v, w, x, y, z, i)
Definition: sha1.c:36
#define R2(v, w, x, y, z, i)
Definition: sha1.c:37
#define R0(v, w, x, y, z, i)
Definition: sha1.c:35
LZX_DECLARE_TABLE(MAINTREE)
cab_ULONG block_remaining
Definition: cabinet.h:222
int header_read
Definition: cabinet.h:219
cab_UWORD main_elements
Definition: cabinet.h:218
cab_LONG intel_filesize
Definition: cabinet.h:224
cab_ULONG R0
Definition: cabinet.h:217
cab_LONG intel_curpos
Definition: cabinet.h:225
LZX_DECLARE_TABLE(PRETREE)
cab_UWORD block_type
Definition: cabinet.h:220
cab_ULONG R2
Definition: cabinet.h:217
cab_ULONG frames_read
Definition: cabinet.h:223
int intel_started
Definition: cabinet.h:226
cab_ULONG R1
Definition: cabinet.h:217
cab_UBYTE * window
Definition: cabinet.h:213
cab_ULONG actual_size
Definition: cabinet.h:215
LZX_DECLARE_TABLE(ALIGNED)
cab_ULONG window_size
Definition: cabinet.h:214
cab_ULONG block_length
Definition: cabinet.h:221
LZX_DECLARE_TABLE(LENGTH)
cab_ULONG window_posn
Definition: cabinet.h:216
cab_ULONG bb
Definition: cabinet.h:235
cab_UBYTE * ip
Definition: cabinet.h:237
int bl
Definition: cabinet.h:236
Definition: ps.c:97
uint32_t ULONG
Definition: typedefs.h:59