Newer
Older
* This file is derived from various .h and .c files from the zlib-1.2.3
* distribution by Jean-loup Gailly and Mark Adler, with some additions
* by Paul Mackerras to aid in implementing Deflate compression and
* decompression for PPP packets. See zlib.h for conditions of
* distribution and use.
*
* Changes that have been made include:
* - changed functions not used outside this file to "local"
* - added minCompression parameter to deflateInit2
* - added Z_PACKET_FLUSH (see zlib.h for details)
* - added inflateIncomp
*/
/*+++++*/
/* zutil.h -- internal interface and configuration of the compression library
* Copyright (C) 1995-2005 Jean-loup Gailly.
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* WARNING: this file should *not* be used by applications. It is
part of the implementation of the compression library and is
subject to change. Applications should only use zlib.h.
*/
#include "u-boot/zlib.h"
/* To avoid a build time warning */
#ifdef STDC
#include <malloc.h>
#endif
#endif
/* compile with -Dlocal if your debugger can't find static symbols */
typedef uch FAR uchf;
typedef unsigned short ush;
typedef ush FAR ushf;
#define ERR_MSG(err) z_errmsg[Z_NEED_DICT-(err)]
#define ERR_RETURN(strm,err) return (strm->msg = (char*)ERR_MSG(err), (err))
/* To be used only when the state is known to be valid */
#ifndef NULL
#define NULL ((void *) 0)
#endif
#endif
/* default windowBits for decompression. MAX_WBITS is for compression only */
#if MAX_MEM_LEVEL >= 8
#endif
/* default memLevel */
#define STORED_BLOCK 0
#define STATIC_TREES 1
#define DYN_TREES 2
/* The three kinds of block type */
#define MIN_MATCH 3
#define MAX_MATCH 258
#define zmemcmp memcmp
#define zmemzero(dest, len) memset(dest, 0, len)
#ifdef DEBUG
#include <stdio.h>
extern int z_verbose;
extern void z_error OF((char *m));
#define Assert(cond,msg) {if(!(cond)) z_error(msg);}
#define Trace(x) {if (z_verbose>=0) fprintf x ;}
#define Tracev(x) {if (z_verbose>0) fprintf x ;}
#define Tracevv(x) {if (z_verbose>1) fprintf x ;}
#define Tracec(c,x) {if (z_verbose>0 && (c)) fprintf x ;}
#define Tracecv(c,x) {if (z_verbose>1 && (c)) fprintf x ;}
#define Assert(cond,msg)
#define Trace(x)
#define Tracev(x)
#define Tracevv(x)
#define Tracec(c,x)
#define Tracecv(c,x)
voidpf zcalloc OF((voidpf opaque, unsigned items, unsigned size));
void zcfree OF((voidpf opaque, voidpf ptr, unsigned size));
(*((strm)->zalloc))((strm)->opaque, (items), (size))
#define ZFREE(strm, addr) (*((strm)->zfree))((strm)->opaque, (voidpf)(addr), 0)
/*+++++*/
/* inftrees.h -- header to use inftrees.c
* Copyright (C) 1995-2005 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* WARNING: this file should *not* be used by applications. It is
part of the implementation of the compression library and is
subject to change. Applications should only use zlib.h.
*/
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
/* Structure for decoding tables. Each entry provides either the
information needed to do the operation requested by the code that
indexed that table entry, or it provides a pointer to another
table that indexes more bits of the code. op indicates whether
the entry is a pointer to another table, a literal, a length or
distance, an end-of-block, or an invalid code. For a table
pointer, the low four bits of op is the number of index bits of
that table. For a length or distance, the low four bits of op
is the number of extra bits to get after the code. bits is
the number of bits in this code or part of the code to drop off
of the bit buffer. val is the actual byte to output in the case
of a literal, the base length or distance, or the offset from
the current table to the next table. Each entry is four bytes. */
typedef struct {
unsigned char op; /* operation, extra bits, table bits */
unsigned char bits; /* bits in this part of the code */
unsigned short val; /* offset in table or code value */
} code;
/* Maximum size of dynamic tree. The maximum found in a long but non-
exhaustive search was 1444 code structures (852 for length/literals
and 592 for distances, the latter actually the result of an
exhaustive search). The true maximum is not known, but the value
below is more than safe. */
#define ENOUGH 2048
#define MAXD 592
/* Type of code to build for inftable() */
typedef enum {
CODES,
LENS,
DISTS
} codetype;
extern int inflate_table OF((codetype type, unsigned short FAR *lens,
unsigned codes, code FAR * FAR *table,
unsigned FAR *bits, unsigned short FAR *work));
/* inflate.h -- internal inflate state definition
* Copyright (C) 1995-2004 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* WARNING: this file should *not* be used by applications. It is
part of the implementation of the compression library and is
subject to change. Applications should only use zlib.h.
*/
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
#define GUNZIP
/* Possible inflate modes between inflate() calls */
typedef enum {
HEAD, /* i: waiting for magic header */
FLAGS, /* i: waiting for method and flags (gzip) */
TIME, /* i: waiting for modification time (gzip) */
OS, /* i: waiting for extra flags and operating system (gzip) */
EXLEN, /* i: waiting for extra length (gzip) */
EXTRA, /* i: waiting for extra bytes (gzip) */
NAME, /* i: waiting for end of file name (gzip) */
COMMENT, /* i: waiting for end of comment (gzip) */
HCRC, /* i: waiting for header crc (gzip) */
DICTID, /* i: waiting for dictionary check value */
DICT, /* waiting for inflateSetDictionary() call */
TYPE, /* i: waiting for type bits, including last-flag bit */
TYPEDO, /* i: same, but skip check to exit inflate on new block */
STORED, /* i: waiting for stored size (length and complement) */
COPY, /* i/o: waiting for input or output to copy stored block */
TABLE, /* i: waiting for dynamic block table lengths */
LENLENS, /* i: waiting for code length code lengths */
CODELENS, /* i: waiting for length/lit and distance code lengths */
LEN, /* i: waiting for length/lit code */
LENEXT, /* i: waiting for length extra bits */
DIST, /* i: waiting for distance code */
DISTEXT, /* i: waiting for distance extra bits */
MATCH, /* o: waiting for output space to copy string */
LIT, /* o: waiting for output space to write literal */
CHECK, /* i: waiting for 32-bit check value */
LENGTH, /* i: waiting for 32-bit length (gzip) */
DONE, /* finished check, done -- remain here until reset */
BAD, /* got a data error -- remain here until reset */
MEM, /* got an inflate() memory error -- remain here until reset */
SYNC, /* looking for synchronization bytes to restart inflate() */
START,
WASH,
END,
BADCODE
} inflate_mode;
/*
State transitions between above modes -
(most modes can go to the BAD or MEM mode -- not shown for clarity)
Process header:
HEAD -> (gzip) or (zlib)
(gzip) -> FLAGS -> TIME -> OS -> EXLEN -> EXTRA -> NAME
NAME -> COMMENT -> HCRC -> TYPE
(zlib) -> DICTID or TYPE
DICTID -> DICT -> TYPE
Read deflate blocks:
TYPE -> STORED or TABLE or LEN or CHECK
STORED -> COPY -> TYPE
TABLE -> LENLENS -> CODELENS -> LEN
Read deflate codes:
LEN -> LENEXT or LIT or TYPE
LENEXT -> DIST -> DISTEXT -> MATCH -> LEN
LIT -> LEN
Process trailer:
CHECK -> LENGTH -> DONE
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
/* state maintained between inflate() calls. Approximately 7K bytes. */
struct inflate_state {
inflate_mode mode; /* current inflate mode */
int last; /* true if processing last block */
int wrap; /* bit 0 true for zlib, bit 1 true for gzip */
int havedict; /* true if dictionary provided */
int flags; /* gzip header method and flags (0 if zlib) */
unsigned dmax; /* zlib header max distance (INFLATE_STRICT) */
unsigned long check; /* protected copy of check value */
unsigned long total; /* protected copy of output count */
gz_headerp head; /* where to save gzip header information */
/* sliding window */
unsigned wbits; /* log base 2 of requested window size */
unsigned wsize; /* window size or zero if not using window */
unsigned whave; /* valid bytes in the window */
unsigned write; /* window write index */
unsigned char FAR *window; /* allocated sliding window, if needed */
/* bit accumulator */
unsigned long hold; /* input bit accumulator */
unsigned bits; /* number of bits in "in" */
/* for string and stored block copying */
unsigned length; /* literal or length of data to copy */
unsigned offset; /* distance back to copy string from */
/* for table and code decoding */
unsigned extra; /* extra bits needed */
/* fixed and dynamic code tables */
code const FAR *lencode; /* starting table for length/literal codes */
code const FAR *distcode; /* starting table for distance codes */
unsigned lenbits; /* index bits for lencode */
unsigned distbits; /* index bits for distcode */
/* dynamic table building */
unsigned ncode; /* number of code length code lengths */
unsigned nlen; /* number of length code lengths */
unsigned ndist; /* number of distance code lengths */
unsigned have; /* number of code lengths in lens[] */
code FAR *next; /* next available space in codes[] */
unsigned short lens[320]; /* temporary storage for code lengths */
unsigned short work[288]; /* work area for code table building */
code codes[ENOUGH]; /* space for code tables */
/* inffast.h -- header to use inffast.c
* Copyright (C) 1995-2003 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* WARNING: this file should *not* be used by applications. It is
part of the implementation of the compression library and is
subject to change. Applications should only use zlib.h.
*/
void inflate_fast OF((z_streamp strm, unsigned start));
/*+++++*/
/* inffixed.h -- table for decoding fixed codes
* Generated automatically by makefixed().
*/
/* WARNING: this file should *not* be used by applications. It
is part of the implementation of the compression library and
is subject to change. Applications should only use zlib.h.
*/
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
static const code lenfix[512] = {
{96,7,0},{0,8,80},{0,8,16},{20,8,115},{18,7,31},{0,8,112},{0,8,48},
{0,9,192},{16,7,10},{0,8,96},{0,8,32},{0,9,160},{0,8,0},{0,8,128},
{0,8,64},{0,9,224},{16,7,6},{0,8,88},{0,8,24},{0,9,144},{19,7,59},
{0,8,120},{0,8,56},{0,9,208},{17,7,17},{0,8,104},{0,8,40},{0,9,176},
{0,8,8},{0,8,136},{0,8,72},{0,9,240},{16,7,4},{0,8,84},{0,8,20},
{21,8,227},{19,7,43},{0,8,116},{0,8,52},{0,9,200},{17,7,13},{0,8,100},
{0,8,36},{0,9,168},{0,8,4},{0,8,132},{0,8,68},{0,9,232},{16,7,8},
{0,8,92},{0,8,28},{0,9,152},{20,7,83},{0,8,124},{0,8,60},{0,9,216},
{18,7,23},{0,8,108},{0,8,44},{0,9,184},{0,8,12},{0,8,140},{0,8,76},
{0,9,248},{16,7,3},{0,8,82},{0,8,18},{21,8,163},{19,7,35},{0,8,114},
{0,8,50},{0,9,196},{17,7,11},{0,8,98},{0,8,34},{0,9,164},{0,8,2},
{0,8,130},{0,8,66},{0,9,228},{16,7,7},{0,8,90},{0,8,26},{0,9,148},
{20,7,67},{0,8,122},{0,8,58},{0,9,212},{18,7,19},{0,8,106},{0,8,42},
{0,9,180},{0,8,10},{0,8,138},{0,8,74},{0,9,244},{16,7,5},{0,8,86},
{0,8,22},{64,8,0},{19,7,51},{0,8,118},{0,8,54},{0,9,204},{17,7,15},
{0,8,102},{0,8,38},{0,9,172},{0,8,6},{0,8,134},{0,8,70},{0,9,236},
{16,7,9},{0,8,94},{0,8,30},{0,9,156},{20,7,99},{0,8,126},{0,8,62},
{0,9,220},{18,7,27},{0,8,110},{0,8,46},{0,9,188},{0,8,14},{0,8,142},
{0,8,78},{0,9,252},{96,7,0},{0,8,81},{0,8,17},{21,8,131},{18,7,31},
{0,8,113},{0,8,49},{0,9,194},{16,7,10},{0,8,97},{0,8,33},{0,9,162},
{0,8,1},{0,8,129},{0,8,65},{0,9,226},{16,7,6},{0,8,89},{0,8,25},
{0,9,146},{19,7,59},{0,8,121},{0,8,57},{0,9,210},{17,7,17},{0,8,105},
{0,8,41},{0,9,178},{0,8,9},{0,8,137},{0,8,73},{0,9,242},{16,7,4},
{0,8,85},{0,8,21},{16,8,258},{19,7,43},{0,8,117},{0,8,53},{0,9,202},
{17,7,13},{0,8,101},{0,8,37},{0,9,170},{0,8,5},{0,8,133},{0,8,69},
{0,9,234},{16,7,8},{0,8,93},{0,8,29},{0,9,154},{20,7,83},{0,8,125},
{0,8,61},{0,9,218},{18,7,23},{0,8,109},{0,8,45},{0,9,186},{0,8,13},
{0,8,141},{0,8,77},{0,9,250},{16,7,3},{0,8,83},{0,8,19},{21,8,195},
{19,7,35},{0,8,115},{0,8,51},{0,9,198},{17,7,11},{0,8,99},{0,8,35},
{0,9,166},{0,8,3},{0,8,131},{0,8,67},{0,9,230},{16,7,7},{0,8,91},
{0,8,27},{0,9,150},{20,7,67},{0,8,123},{0,8,59},{0,9,214},{18,7,19},
{0,8,107},{0,8,43},{0,9,182},{0,8,11},{0,8,139},{0,8,75},{0,9,246},
{16,7,5},{0,8,87},{0,8,23},{64,8,0},{19,7,51},{0,8,119},{0,8,55},
{0,9,206},{17,7,15},{0,8,103},{0,8,39},{0,9,174},{0,8,7},{0,8,135},
{0,8,71},{0,9,238},{16,7,9},{0,8,95},{0,8,31},{0,9,158},{20,7,99},
{0,8,127},{0,8,63},{0,9,222},{18,7,27},{0,8,111},{0,8,47},{0,9,190},
{0,8,15},{0,8,143},{0,8,79},{0,9,254},{96,7,0},{0,8,80},{0,8,16},
{20,8,115},{18,7,31},{0,8,112},{0,8,48},{0,9,193},{16,7,10},{0,8,96},
{0,8,32},{0,9,161},{0,8,0},{0,8,128},{0,8,64},{0,9,225},{16,7,6},
{0,8,88},{0,8,24},{0,9,145},{19,7,59},{0,8,120},{0,8,56},{0,9,209},
{17,7,17},{0,8,104},{0,8,40},{0,9,177},{0,8,8},{0,8,136},{0,8,72},
{0,9,241},{16,7,4},{0,8,84},{0,8,20},{21,8,227},{19,7,43},{0,8,116},
{0,8,52},{0,9,201},{17,7,13},{0,8,100},{0,8,36},{0,9,169},{0,8,4},
{0,8,132},{0,8,68},{0,9,233},{16,7,8},{0,8,92},{0,8,28},{0,9,153},
{20,7,83},{0,8,124},{0,8,60},{0,9,217},{18,7,23},{0,8,108},{0,8,44},
{0,9,185},{0,8,12},{0,8,140},{0,8,76},{0,9,249},{16,7,3},{0,8,82},
{0,8,18},{21,8,163},{19,7,35},{0,8,114},{0,8,50},{0,9,197},{17,7,11},
{0,8,98},{0,8,34},{0,9,165},{0,8,2},{0,8,130},{0,8,66},{0,9,229},
{16,7,7},{0,8,90},{0,8,26},{0,9,149},{20,7,67},{0,8,122},{0,8,58},
{0,9,213},{18,7,19},{0,8,106},{0,8,42},{0,9,181},{0,8,10},{0,8,138},
{0,8,74},{0,9,245},{16,7,5},{0,8,86},{0,8,22},{64,8,0},{19,7,51},
{0,8,118},{0,8,54},{0,9,205},{17,7,15},{0,8,102},{0,8,38},{0,9,173},
{0,8,6},{0,8,134},{0,8,70},{0,9,237},{16,7,9},{0,8,94},{0,8,30},
{0,9,157},{20,7,99},{0,8,126},{0,8,62},{0,9,221},{18,7,27},{0,8,110},
{0,8,46},{0,9,189},{0,8,14},{0,8,142},{0,8,78},{0,9,253},{96,7,0},
{0,8,81},{0,8,17},{21,8,131},{18,7,31},{0,8,113},{0,8,49},{0,9,195},
{16,7,10},{0,8,97},{0,8,33},{0,9,163},{0,8,1},{0,8,129},{0,8,65},
{0,9,227},{16,7,6},{0,8,89},{0,8,25},{0,9,147},{19,7,59},{0,8,121},
{0,8,57},{0,9,211},{17,7,17},{0,8,105},{0,8,41},{0,9,179},{0,8,9},
{0,8,137},{0,8,73},{0,9,243},{16,7,4},{0,8,85},{0,8,21},{16,8,258},
{19,7,43},{0,8,117},{0,8,53},{0,9,203},{17,7,13},{0,8,101},{0,8,37},
{0,9,171},{0,8,5},{0,8,133},{0,8,69},{0,9,235},{16,7,8},{0,8,93},
{0,8,29},{0,9,155},{20,7,83},{0,8,125},{0,8,61},{0,9,219},{18,7,23},
{0,8,109},{0,8,45},{0,9,187},{0,8,13},{0,8,141},{0,8,77},{0,9,251},
{16,7,3},{0,8,83},{0,8,19},{21,8,195},{19,7,35},{0,8,115},{0,8,51},
{0,9,199},{17,7,11},{0,8,99},{0,8,35},{0,9,167},{0,8,3},{0,8,131},
{0,8,67},{0,9,231},{16,7,7},{0,8,91},{0,8,27},{0,9,151},{20,7,67},
{0,8,123},{0,8,59},{0,9,215},{18,7,19},{0,8,107},{0,8,43},{0,9,183},
{0,8,11},{0,8,139},{0,8,75},{0,9,247},{16,7,5},{0,8,87},{0,8,23},
{64,8,0},{19,7,51},{0,8,119},{0,8,55},{0,9,207},{17,7,15},{0,8,103},
{0,8,39},{0,9,175},{0,8,7},{0,8,135},{0,8,71},{0,9,239},{16,7,9},
{0,8,95},{0,8,31},{0,9,159},{20,7,99},{0,8,127},{0,8,63},{0,9,223},
{18,7,27},{0,8,111},{0,8,47},{0,9,191},{0,8,15},{0,8,143},{0,8,79},
{0,9,255}
};
static const code distfix[32] = {
{16,5,1},{23,5,257},{19,5,17},{27,5,4097},{17,5,5},{25,5,1025},
{21,5,65},{29,5,16385},{16,5,3},{24,5,513},{20,5,33},{28,5,8193},
{18,5,9},{26,5,2049},{22,5,129},{64,5,0},{16,5,2},{23,5,385},
{19,5,25},{27,5,6145},{17,5,7},{25,5,1537},{21,5,97},{29,5,24577},
{16,5,4},{24,5,769},{20,5,49},{28,5,12289},{18,5,13},{26,5,3073},
{22,5,193},{64,5,0}
};
/* inffast.c -- fast decoding
* Copyright (C) 1995-2004 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* Allow machine dependent optimization for post-increment or pre-increment.
Based on testing to date,
Pre-increment preferred for:
- PowerPC G3 (Adler)
- MIPS R5000 (Randers-Pehrson)
Post-increment preferred for:
- none
No measurable difference:
- Pentium III (Anderson)
- M68060 (Nikl)
*/
#define OFF 1
#define PUP(a) *++(a)
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
Decode literal, length, and distance codes and write out the resulting
literal and match bytes until either not enough input or output is
available, an end-of-block is encountered, or a data error is encountered.
When large enough input and output buffers are supplied to inflate(), for
example, a 16K input buffer and a 64K output buffer, more than 95% of the
inflate execution time is spent in this routine.
Entry assumptions:
state->mode == LEN
strm->avail_in >= 6
strm->avail_out >= 258
start >= strm->avail_out
state->bits < 8
On return, state->mode is one of:
LEN -- ran out of enough output space or enough available input
TYPE -- reached end of block code, inflate() to interpret next block
BAD -- error in block data
Notes:
- The maximum input bits used by a length/distance pair is 15 bits for the
length code, 5 bits for the length extra, 15 bits for the distance code,
and 13 bits for the distance extra. This totals 48 bits, or six bytes.
Therefore if strm->avail_in >= 6, then there is enough input to avoid
checking for available input while decoding.
- The maximum bytes that a single length/distance pair can output is 258
bytes, which is the maximum length that can be coded. inflate_fast()
requires strm->avail_out >= 258 for each loop to avoid checking for
output space.
void inflate_fast(strm, start)
z_streamp strm;
unsigned start; /* inflate()'s starting value for strm->avail_out */
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
struct inflate_state FAR *state;
unsigned char FAR *in; /* local strm->next_in */
unsigned char FAR *last; /* while in < last, enough input available */
unsigned char FAR *out; /* local strm->next_out */
unsigned char FAR *beg; /* inflate()'s initial strm->next_out */
unsigned char FAR *end; /* while out < end, enough space available */
#ifdef INFLATE_STRICT
unsigned dmax; /* maximum distance from zlib header */
#endif
unsigned wsize; /* window size or zero if not using window */
unsigned whave; /* valid bytes in the window */
unsigned write; /* window write index */
unsigned char FAR *window; /* allocated sliding window, if wsize != 0 */
unsigned long hold; /* local strm->hold */
unsigned bits; /* local strm->bits */
code const FAR *lcode; /* local strm->lencode */
code const FAR *dcode; /* local strm->distcode */
unsigned lmask; /* mask for first level of length codes */
unsigned dmask; /* mask for first level of distance codes */
code this; /* retrieved table entry */
unsigned op; /* code bits, operation, extra bits, or */
/* window position, window bytes to copy */
unsigned len; /* match length, unused bytes */
unsigned dist; /* match distance */
unsigned char FAR *from; /* where to copy match from */
/* copy state to local variables */
state = (struct inflate_state FAR *)strm->state;
in = strm->next_in - OFF;
last = in + (strm->avail_in - 5);
out = strm->next_out - OFF;
beg = out - (start - strm->avail_out);
end = out + (strm->avail_out - 257);
#ifdef INFLATE_STRICT
dmax = state->dmax;
#endif
wsize = state->wsize;
whave = state->whave;
write = state->write;
window = state->window;
hold = state->hold;
bits = state->bits;
lcode = state->lencode;
dcode = state->distcode;
lmask = (1U << state->lenbits) - 1;
dmask = (1U << state->distbits) - 1;
/* decode literals and length/distances until end-of-block or not enough
input data or output space */
do {
if (bits < 15) {
hold += (unsigned long)(PUP(in)) << bits;
bits += 8;
hold += (unsigned long)(PUP(in)) << bits;
bits += 8;
}
this = lcode[hold & lmask];
dolen:
op = (unsigned)(this.bits);
hold >>= op;
bits -= op;
op = (unsigned)(this.op);
if (op == 0) { /* literal */
Tracevv((stderr, this.val >= 0x20 && this.val < 0x7f ?
"inflate: literal '%c'\n" :
"inflate: literal 0x%02x\n", this.val));
PUP(out) = (unsigned char)(this.val);
}
else if (op & 16) { /* length base */
len = (unsigned)(this.val);
op &= 15; /* number of extra bits */
if (op) {
if (bits < op) {
hold += (unsigned long)(PUP(in)) << bits;
bits += 8;
}
len += (unsigned)hold & ((1U << op) - 1);
hold >>= op;
bits -= op;
}
Tracevv((stderr, "inflate: length %u\n", len));
if (bits < 15) {
hold += (unsigned long)(PUP(in)) << bits;
bits += 8;
hold += (unsigned long)(PUP(in)) << bits;
bits += 8;
}
this = dcode[hold & dmask];
dodist:
op = (unsigned)(this.bits);
hold >>= op;
bits -= op;
op = (unsigned)(this.op);
if (op & 16) { /* distance base */
dist = (unsigned)(this.val);
op &= 15; /* number of extra bits */
if (bits < op) {
hold += (unsigned long)(PUP(in)) << bits;
bits += 8;
if (bits < op) {
hold += (unsigned long)(PUP(in)) << bits;
bits += 8;
}
}
dist += (unsigned)hold & ((1U << op) - 1);
#ifdef INFLATE_STRICT
if (dist > dmax) {
strm->msg = (char *)"invalid distance too far back";
state->mode = BAD;
break;
}
#endif
hold >>= op;
bits -= op;
Tracevv((stderr, "inflate: distance %u\n", dist));
op = (unsigned)(out - beg); /* max distance in output */
if (dist > op) { /* see if copy from window */
op = dist - op; /* distance back in window */
if (op > whave) {
strm->msg = (char *)"invalid distance too far back";
state->mode = BAD;
break;
}
from = window - OFF;
if (write == 0) { /* very common case */
from += wsize - op;
if (op < len) { /* some from window */
len -= op;
do {
PUP(out) = PUP(from);
} while (--op);
from = out - dist; /* rest from output */
}
}
else if (write < op) { /* wrap around window */
from += wsize + write - op;
op -= write;
if (op < len) { /* some from end of window */
len -= op;
do {
PUP(out) = PUP(from);
} while (--op);
from = window - OFF;
if (write < len) { /* some from start of window */
op = write;
len -= op;
do {
PUP(out) = PUP(from);
} while (--op);
from = out - dist; /* rest from output */
}
}
}
else { /* contiguous in window */
from += write - op;
if (op < len) { /* some from window */
len -= op;
do {
PUP(out) = PUP(from);
} while (--op);
from = out - dist; /* rest from output */
}
}
while (len > 2) {
PUP(out) = PUP(from);
PUP(out) = PUP(from);
PUP(out) = PUP(from);
len -= 3;
}
if (len) {
PUP(out) = PUP(from);
if (len > 1)
PUP(out) = PUP(from);
}
}
else {
from = out - dist; /* copy direct from output */
do { /* minimum length is three */
PUP(out) = PUP(from);
PUP(out) = PUP(from);
PUP(out) = PUP(from);
len -= 3;
} while (len > 2);
if (len) {
PUP(out) = PUP(from);
if (len > 1)
PUP(out) = PUP(from);
}
}
}
else if ((op & 64) == 0) { /* 2nd level distance code */
this = dcode[this.val + (hold & ((1U << op) - 1))];
goto dodist;
}
else {
strm->msg = (char *)"invalid distance code";
state->mode = BAD;
break;
}
}
else if ((op & 64) == 0) { /* 2nd level length code */
this = lcode[this.val + (hold & ((1U << op) - 1))];
goto dolen;
}
else if (op & 32) { /* end-of-block */
Tracevv((stderr, "inflate: end of block\n"));
state->mode = TYPE;
break;
}
else {
strm->msg = (char *)"invalid literal/length code";
state->mode = BAD;
break;
}
} while (in < last && out < end);
/* return unused bytes (on entry, bits < 8, so in won't go too far back) */
len = bits >> 3;
in -= len;
bits -= len << 3;
hold &= (1U << bits) - 1;
/* update state and return */
strm->next_in = in + OFF;
strm->next_out = out + OFF;
strm->avail_in = (unsigned)(in < last ? 5 + (last - in) : 5 - (in - last));
strm->avail_out = (unsigned)(out < end ?
257 + (end - out) : 257 - (out - end));
state->hold = hold;
state->bits = bits;
return;
inflate_fast() speedups that turned out slower (on a PowerPC G3 750CXe):
- Using bit fields for code structure
- Different op definition to avoid & for extra bits (do & for table bits)
- Three separate decoding do-loops for direct, window, and write == 0
- Special case for distance > 1 copies to do overlapped load and store copy
- Explicit branch predictions (based on measured branch probabilities)
- Deferring match copy and interspersed it with decoding subsequent codes
- Swapping literal/length else
- Swapping window/direct else
- Larger unrolled copy loops (three is about right)
- Moving len -= 3 statement into middle of loop
/* inftrees.c -- generate Huffman trees for efficient decoding
* Copyright (C) 1995-2005 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
#define MAXBITS 15
/*
If you use the zlib library in a product, an acknowledgment is welcome
in the documentation of your product. If for some reason you cannot
include such an acknowledgment, I would appreciate that you keep this
copyright string in the executable of your product.
Build a set of tables to decode the provided canonical Huffman code.
The code lengths are lens[0..codes-1]. The result starts at *table,
whose indices are 0..2^bits-1. work is a writable array of at least
lens shorts, which is used as a work area. type is the type of code
to be generated, CODES, LENS, or DISTS. On return, zero is success,
-1 is an invalid code, and +1 means that ENOUGH isn't enough. table
on return points to the next available entry's address. bits is the
requested root table index bits, and on return it is the actual root
table index bits. It will differ if the request is greater than the
longest code or if it is less than the shortest code.
int inflate_table(type, lens, codes, table, bits, work)
codetype type;
unsigned short FAR *lens;
unsigned codes;
code FAR * FAR *table;
unsigned FAR *bits;
unsigned short FAR *work;
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
unsigned len; /* a code's length in bits */
unsigned sym; /* index of code symbols */
unsigned min, max; /* minimum and maximum code lengths */
unsigned root; /* number of index bits for root table */
unsigned curr; /* number of index bits for current table */
unsigned drop; /* code bits to drop for sub-table */
int left; /* number of prefix codes available */
unsigned used; /* code entries in table used */
unsigned huff; /* Huffman code */
unsigned incr; /* for incrementing code, index */
unsigned fill; /* index for replicating entries */
unsigned low; /* low bits for current root entry */
unsigned mask; /* mask for low root bits */
code this; /* table entry for duplication */
code FAR *next; /* next available space in table */
const unsigned short FAR *base; /* base value table to use */
const unsigned short FAR *extra; /* extra bits table to use */
int end; /* use base and extra for symbol > end */
unsigned short count[MAXBITS+1]; /* number of codes of each length */
unsigned short offs[MAXBITS+1]; /* offsets in table for each length */
static const unsigned short lbase[31] = { /* Length codes 257..285 base */
3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
static const unsigned short lext[31] = { /* Length codes 257..285 extra */
16, 16, 16, 16, 16, 16, 16, 16, 17, 17, 17, 17, 18, 18, 18, 18,
19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 16, 201, 196};
static const unsigned short dbase[32] = { /* Distance codes 0..29 base */
1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
8193, 12289, 16385, 24577, 0, 0};
static const unsigned short dext[32] = { /* Distance codes 0..29 extra */
16, 16, 16, 16, 17, 17, 18, 18, 19, 19, 20, 20, 21, 21, 22, 22,
23, 23, 24, 24, 25, 25, 26, 26, 27, 27,
28, 28, 29, 29, 64, 64};
/*
Process a set of code lengths to create a canonical Huffman code. The
code lengths are lens[0..codes-1]. Each length corresponds to the
symbols 0..codes-1. The Huffman code is generated by first sorting the
symbols by length from short to long, and retaining the symbol order
for codes with equal lengths. Then the code starts with all zero bits
for the first code of the shortest length, and the codes are integer
increments for the same length, and zeros are appended as the length
increases. For the deflate format, these bits are stored backwards
from their more natural integer increment ordering, and so when the
decoding tables are built in the large loop below, the integer codes
are incremented backwards.
This routine assumes, but does not check, that all of the entries in
lens[] are in the range 0..MAXBITS. The caller must assure this.
1..MAXBITS is interpreted as that code length. zero means that that
symbol does not occur in this code.
The codes are sorted by computing a count of codes for each length,
creating from that a table of starting indices for each length in the
sorted table, and then entering the symbols in order in the sorted
table. The sorted table is work[], with that space being provided by
the caller.
The length counts are used for other purposes as well, i.e. finding
the minimum and maximum length codes, determining if there are any
codes at all, checking for a valid set of lengths, and looking ahead
at length counts to determine sub-table sizes when building the
decoding tables.
*/
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
/* accumulate lengths for codes (assumes lens[] all in 0..MAXBITS) */
for (len = 0; len <= MAXBITS; len++)
count[len] = 0;
for (sym = 0; sym < codes; sym++)
count[lens[sym]]++;
/* bound code lengths, force root to be within code lengths */
root = *bits;
for (max = MAXBITS; max >= 1; max--)
if (count[max] != 0) break;
if (root > max) root = max;
if (max == 0) { /* no symbols to code at all */
this.op = (unsigned char)64; /* invalid code marker */
this.bits = (unsigned char)1;
this.val = (unsigned short)0;
*(*table)++ = this; /* make a table to force an error */
*(*table)++ = this;
*bits = 1;
return 0; /* no symbols, but wait for decoding to report error */
}
for (min = 1; min <= MAXBITS; min++)
if (count[min] != 0) break;
if (root < min) root = min;
/* check for an over-subscribed or incomplete set of lengths */
left = 1;
for (len = 1; len <= MAXBITS; len++) {
left <<= 1;
left -= count[len];
if (left < 0) return -1; /* over-subscribed */
}
if (left > 0 && (type == CODES || max != 1))
return -1; /* incomplete set */
/* generate offsets into symbol table for each length for sorting */
offs[1] = 0;
for (len = 1; len < MAXBITS; len++)
offs[len + 1] = offs[len] + count[len];
/* sort symbols by length, by symbol order within each length */
for (sym = 0; sym < codes; sym++)
if (lens[sym] != 0) work[offs[lens[sym]]++] = (unsigned short)sym;
/*
Create and fill in decoding tables. In this loop, the table being
filled is at next and has curr index bits. The code being used is huff
with length len. That code is converted to an index by dropping drop
bits off of the bottom. For codes where len is less than drop + curr,
those top drop + curr - len bits are incremented through all values to
fill the table with replicated entries.
root is the number of index bits for the root table. When len exceeds
root, sub-tables are created pointed to by the root entry with an index
of the low root bits of huff. This is saved in low to check for when a
new sub-table should be started. drop is zero when the root table is
being filled, and drop is root when sub-tables are being filled.
When a new sub-table is needed, it is necessary to look ahead in the
code lengths to determine what size sub-table is needed. The length
counts are used for this, and so count[] is decremented as codes are
entered in the tables.
used keeps track of how many table entries have been allocated from the
provided *table space. It is checked when a LENS table is being made
against the space in *table, ENOUGH, minus the maximum space needed by
the worst case distance code, MAXD. This should never happen, but the
sufficiency of ENOUGH has not been proven exhaustively, hence the check.
This assumes that when type == LENS, bits == 9.
sym increments through all symbols, and the loop terminates when
all codes of length max, i.e. all codes, have been processed. This
routine permits incomplete codes, so another loop after this one fills
in the rest of the decoding tables with invalid code markers.
*/
/* set up for code type */
switch (type) {
base = extra = work; /* dummy value--not used */
end = 19;
break;
case LENS:
base = lbase;
base -= 257;
extra = lext;
extra -= 257;
end = 256;
break;
default: /* DISTS */
base = dbase;
extra = dext;
end = -1;
}
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
/* initialize state for loop */
huff = 0; /* starting code */
sym = 0; /* starting code symbol */
len = min; /* starting code length */
next = *table; /* current table to fill in */
curr = root; /* current table index bits */
drop = 0; /* current bits to drop from code for index */
low = (unsigned)(-1); /* trigger new sub-table when len > root */
used = 1U << root; /* use root table entries */
mask = used - 1; /* mask for comparing low */
/* check available table space */
if (type == LENS && used >= ENOUGH - MAXD)
return 1;
/* process all codes and make table entries */
for (;;) {
/* create table entry */
this.bits = (unsigned char)(len - drop);
if ((int)(work[sym]) < end) {
this.op = (unsigned char)0;
this.val = work[sym];
}
else if ((int)(work[sym]) > end) {
this.op = (unsigned char)(extra[work[sym]]);
this.val = base[work[sym]];
}
else {
this.op = (unsigned char)(32 + 64); /* end of block */
this.val = 0;
}
/* replicate for those indices with low len bits equal to huff */
incr = 1U << (len - drop);
fill = 1U << curr;
min = fill; /* save offset to next table */
do {
fill -= incr;
next[(huff >> drop) + fill] = this;
} while (fill != 0);
/* backwards increment the len-bit code huff */
incr = 1U << (len - 1);
while (huff & incr)
incr >>= 1;
if (incr != 0) {
huff &= incr - 1;
huff += incr;
}
else
huff = 0;
/* go to next symbol, update count, len */
sym++;
if (--(count[len]) == 0) {
if (len == max) break;
len = lens[work[sym]];
}
/* create new sub-table if needed */
if (len > root && (huff & mask) != low) {
/* if first time, transition to sub-tables */
if (drop == 0)
drop = root;
/* increment past last table */
next += min; /* here min is 1 << curr */
/* determine length of next table */
curr = len - drop;
left = (int)(1 << curr);
while (curr + drop < max) {
left -= count[curr + drop];
if (left <= 0) break;
curr++;
left <<= 1;
}
/* check for enough space */
used += 1U << curr;
if (type == LENS && used >= ENOUGH - MAXD)
return 1;
/* point entry in root table to sub-table */
low = huff & mask;
(*table)[low].op = (unsigned char)curr;
(*table)[low].bits = (unsigned char)root;
(*table)[low].val = (unsigned short)(next - *table);
}
}
/*
Fill in rest of table for incomplete codes. This loop is similar to the
loop above in incrementing huff for table indices. It is assumed that
len is equal to curr + drop, so there is no loop needed to increment
through high index bits. When the current sub-table is filled, the loop
drops back to the root table to fill in any remaining entries there.
this.op = (unsigned char)64; /* invalid code marker */
this.bits = (unsigned char)(len - drop);
this.val = (unsigned short)0;
while (huff != 0) {
/* when done with sub-table, drop back to root table */
if (drop != 0 && (huff & mask) != low) {
drop = 0;
len = root;
next = *table;
this.bits = (unsigned char)len;
}
/* put invalid code marker in table */
next[huff >> drop] = this;
/* backwards increment the len-bit code huff */
incr = 1U << (len - 1);
while (huff & incr)
incr >>= 1;
if (incr != 0) {