File: /usr/src/linux/arch/ppc/boot/lib/zlib.c
1 /*
2 * BK Id: SCCS/s.zlib.c 1.8 05/18/01 15:17:24 cort
3 */
4 /*
5 * This file is derived from various .h and .c files from the zlib-0.95
6 * distribution by Jean-loup Gailly and Mark Adler, with some additions
7 * by Paul Mackerras to aid in implementing Deflate compression and
8 * decompression for PPP packets. See zlib.h for conditions of
9 * distribution and use.
10 *
11 * Changes that have been made include:
12 * - changed functions not used outside this file to "local"
13 * - added minCompression parameter to deflateInit2
14 * - added Z_PACKET_FLUSH (see zlib.h for details)
15 * - added inflateIncomp
16 *
17 */
18
19 /*+++++*/
20 /* zutil.h -- internal interface and configuration of the compression library
21 * Copyright (C) 1995 Jean-loup Gailly.
22 * For conditions of distribution and use, see copyright notice in zlib.h
23 */
24
25 /* WARNING: this file should *not* be used by applications. It is
26 part of the implementation of the compression library and is
27 subject to change. Applications should only use zlib.h.
28 */
29
30 /* From: zutil.h,v 1.9 1995/05/03 17:27:12 jloup Exp */
31
32 #define _Z_UTIL_H
33
34 #include "zlib.h"
35
36 #ifndef local
37 # define local static
38 #endif
39 /* compile with -Dlocal if your debugger can't find static symbols */
40
41 #define FAR
42
43 typedef unsigned char uch;
44 typedef uch FAR uchf;
45 typedef unsigned short ush;
46 typedef ush FAR ushf;
47 typedef unsigned long ulg;
48
49 extern char *z_errmsg[]; /* indexed by 1-zlib_error */
50
51 #define ERR_RETURN(strm,err) return (strm->msg=z_errmsg[1-err], err)
52 /* To be used only when the state is known to be valid */
53
54 #ifndef NULL
55 #define NULL ((void *) 0)
56 #endif
57
58 /* common constants */
59
60 #define DEFLATED 8
61
62 #ifndef DEF_WBITS
63 # define DEF_WBITS MAX_WBITS
64 #endif
65 /* default windowBits for decompression. MAX_WBITS is for compression only */
66
67 #if MAX_MEM_LEVEL >= 8
68 # define DEF_MEM_LEVEL 8
69 #else
70 # define DEF_MEM_LEVEL MAX_MEM_LEVEL
71 #endif
72 /* default memLevel */
73
74 #define STORED_BLOCK 0
75 #define STATIC_TREES 1
76 #define DYN_TREES 2
77 /* The three kinds of block type */
78
79 #define MIN_MATCH 3
80 #define MAX_MATCH 258
81 /* The minimum and maximum match lengths */
82
83 /* functions */
84
85 #include <linux/string.h>
86 #define zmemcpy memcpy
87 #define zmemzero(dest, len) memset(dest, 0, len)
88
89 /* Diagnostic functions */
90 #ifdef DEBUG_ZLIB
91 # include <stdio.h>
92 # ifndef verbose
93 # define verbose 0
94 # endif
95 # define Assert(cond,msg) {if(!(cond)) z_error(msg);}
96 # define Trace(x) fprintf x
97 # define Tracev(x) {if (verbose) fprintf x ;}
98 # define Tracevv(x) {if (verbose>1) fprintf x ;}
99 # define Tracec(c,x) {if (verbose && (c)) fprintf x ;}
100 # define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;}
101 #else
102 # define Assert(cond,msg)
103 # define Trace(x)
104 # define Tracev(x)
105 # define Tracevv(x)
106 # define Tracec(c,x)
107 # define Tracecv(c,x)
108 #endif
109
110
111 typedef uLong (*check_func) OF((uLong check, Bytef *buf, uInt len));
112
113 /* voidpf zcalloc OF((voidpf opaque, unsigned items, unsigned size)); */
114 /* void zcfree OF((voidpf opaque, voidpf ptr)); */
115
116 #define ZALLOC(strm, items, size) \
117 (*((strm)->zalloc))((strm)->opaque, (items), (size))
118 #define ZFREE(strm, addr, size) \
119 (*((strm)->zfree))((strm)->opaque, (voidpf)(addr), (size))
120 #define TRY_FREE(s, p, n) {if (p) ZFREE(s, p, n);}
121
122 /* deflate.h -- internal compression state
123 * Copyright (C) 1995 Jean-loup Gailly
124 * For conditions of distribution and use, see copyright notice in zlib.h
125 */
126
127 /* WARNING: this file should *not* be used by applications. It is
128 part of the implementation of the compression library and is
129 subject to change. Applications should only use zlib.h.
130 */
131
132 /*+++++*/
133 /* infblock.h -- header to use infblock.c
134 * Copyright (C) 1995 Mark Adler
135 * For conditions of distribution and use, see copyright notice in zlib.h
136 */
137
138 /* WARNING: this file should *not* be used by applications. It is
139 part of the implementation of the compression library and is
140 subject to change. Applications should only use zlib.h.
141 */
142
143 struct inflate_blocks_state;
144 typedef struct inflate_blocks_state FAR inflate_blocks_statef;
145
146 local inflate_blocks_statef * inflate_blocks_new OF((
147 z_stream *z,
148 check_func c, /* check function */
149 uInt w)); /* window size */
150
151 local int inflate_blocks OF((
152 inflate_blocks_statef *,
153 z_stream *,
154 int)); /* initial return code */
155
156 local void inflate_blocks_reset OF((
157 inflate_blocks_statef *,
158 z_stream *,
159 uLongf *)); /* check value on output */
160
161 local int inflate_blocks_free OF((
162 inflate_blocks_statef *,
163 z_stream *,
164 uLongf *)); /* check value on output */
165
166 local int inflate_addhistory OF((
167 inflate_blocks_statef *,
168 z_stream *));
169
170 local int inflate_packet_flush OF((
171 inflate_blocks_statef *));
172
173 /*+++++*/
174 /* inftrees.h -- header to use inftrees.c
175 * Copyright (C) 1995 Mark Adler
176 * For conditions of distribution and use, see copyright notice in zlib.h
177 */
178
179 /* WARNING: this file should *not* be used by applications. It is
180 part of the implementation of the compression library and is
181 subject to change. Applications should only use zlib.h.
182 */
183
184 /* Huffman code lookup table entry--this entry is four bytes for machines
185 that have 16-bit pointers (e.g. PC's in the small or medium model). */
186
187 typedef struct inflate_huft_s FAR inflate_huft;
188
189 struct inflate_huft_s {
190 union {
191 struct {
192 Byte Exop; /* number of extra bits or operation */
193 Byte Bits; /* number of bits in this code or subcode */
194 } what;
195 uInt Nalloc; /* number of these allocated here */
196 Bytef *pad; /* pad structure to a power of 2 (4 bytes for */
197 } word; /* 16-bit, 8 bytes for 32-bit machines) */
198 union {
199 uInt Base; /* literal, length base, or distance base */
200 inflate_huft *Next; /* pointer to next level of table */
201 } more;
202 };
203
204 #ifdef DEBUG_ZLIB
205 local uInt inflate_hufts;
206 #endif
207
208 local int inflate_trees_bits OF((
209 uIntf *, /* 19 code lengths */
210 uIntf *, /* bits tree desired/actual depth */
211 inflate_huft * FAR *, /* bits tree result */
212 z_stream *)); /* for zalloc, zfree functions */
213
214 local int inflate_trees_dynamic OF((
215 uInt, /* number of literal/length codes */
216 uInt, /* number of distance codes */
217 uIntf *, /* that many (total) code lengths */
218 uIntf *, /* literal desired/actual bit depth */
219 uIntf *, /* distance desired/actual bit depth */
220 inflate_huft * FAR *, /* literal/length tree result */
221 inflate_huft * FAR *, /* distance tree result */
222 z_stream *)); /* for zalloc, zfree functions */
223
224 local int inflate_trees_fixed OF((
225 uIntf *, /* literal desired/actual bit depth */
226 uIntf *, /* distance desired/actual bit depth */
227 inflate_huft * FAR *, /* literal/length tree result */
228 inflate_huft * FAR *)); /* distance tree result */
229
230 local int inflate_trees_free OF((
231 inflate_huft *, /* tables to free */
232 z_stream *)); /* for zfree function */
233
234
235 /*+++++*/
236 /* infcodes.h -- header to use infcodes.c
237 * Copyright (C) 1995 Mark Adler
238 * For conditions of distribution and use, see copyright notice in zlib.h
239 */
240
241 /* WARNING: this file should *not* be used by applications. It is
242 part of the implementation of the compression library and is
243 subject to change. Applications should only use zlib.h.
244 */
245
246 struct inflate_codes_state;
247 typedef struct inflate_codes_state FAR inflate_codes_statef;
248
249 local inflate_codes_statef *inflate_codes_new OF((
250 uInt, uInt,
251 inflate_huft *, inflate_huft *,
252 z_stream *));
253
254 local int inflate_codes OF((
255 inflate_blocks_statef *,
256 z_stream *,
257 int));
258
259 local void inflate_codes_free OF((
260 inflate_codes_statef *,
261 z_stream *));
262
263
264 /*+++++*/
265 /* inflate.c -- zlib interface to inflate modules
266 * Copyright (C) 1995 Mark Adler
267 * For conditions of distribution and use, see copyright notice in zlib.h
268 */
269
270 /* inflate private state */
271 struct internal_state {
272
273 /* mode */
274 enum {
275 METHOD, /* waiting for method byte */
276 FLAG, /* waiting for flag byte */
277 BLOCKS, /* decompressing blocks */
278 CHECK4, /* four check bytes to go */
279 CHECK3, /* three check bytes to go */
280 CHECK2, /* two check bytes to go */
281 CHECK1, /* one check byte to go */
282 DONE, /* finished check, done */
283 BAD} /* got an error--stay here */
284 mode; /* current inflate mode */
285
286 /* mode dependent information */
287 union {
288 uInt method; /* if FLAGS, method byte */
289 struct {
290 uLong was; /* computed check value */
291 uLong need; /* stream check value */
292 } check; /* if CHECK, check values to compare */
293 uInt marker; /* if BAD, inflateSync's marker bytes count */
294 } sub; /* submode */
295
296 /* mode independent information */
297 int nowrap; /* flag for no wrapper */
298 uInt wbits; /* log2(window size) (8..15, defaults to 15) */
299 inflate_blocks_statef
300 *blocks; /* current inflate_blocks state */
301
302 };
303
304
305 int inflateReset(z)
306 z_stream *z;
307 {
308 uLong c;
309
310 if (z == Z_NULL || z->state == Z_NULL)
311 return Z_STREAM_ERROR;
312 z->total_in = z->total_out = 0;
313 z->msg = Z_NULL;
314 z->state->mode = z->state->nowrap ? BLOCKS : METHOD;
315 inflate_blocks_reset(z->state->blocks, z, &c);
316 Trace((stderr, "inflate: reset\n"));
317 return Z_OK;
318 }
319
320
321 int inflateEnd(z)
322 z_stream *z;
323 {
324 uLong c;
325
326 if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL)
327 return Z_STREAM_ERROR;
328 if (z->state->blocks != Z_NULL)
329 inflate_blocks_free(z->state->blocks, z, &c);
330 ZFREE(z, z->state, sizeof(struct internal_state));
331 z->state = Z_NULL;
332 Trace((stderr, "inflate: end\n"));
333 return Z_OK;
334 }
335
336
337 int inflateInit2(z, w)
338 z_stream *z;
339 int w;
340 {
341 /* initialize state */
342 if (z == Z_NULL)
343 return Z_STREAM_ERROR;
344 /* if (z->zalloc == Z_NULL) z->zalloc = zcalloc; */
345 /* if (z->zfree == Z_NULL) z->zfree = zcfree; */
346 if ((z->state = (struct internal_state FAR *)
347 ZALLOC(z,1,sizeof(struct internal_state))) == Z_NULL)
348 return Z_MEM_ERROR;
349 z->state->blocks = Z_NULL;
350
351 /* handle undocumented nowrap option (no zlib header or check) */
352 z->state->nowrap = 0;
353 if (w < 0)
354 {
355 w = - w;
356 z->state->nowrap = 1;
357 }
358
359 /* set window size */
360 if (w < 8 || w > 15)
361 {
362 inflateEnd(z);
363 return Z_STREAM_ERROR;
364 }
365 z->state->wbits = (uInt)w;
366
367 /* create inflate_blocks state */
368 if ((z->state->blocks =
369 inflate_blocks_new(z, z->state->nowrap ? Z_NULL : adler32, 1 << w))
370 == Z_NULL)
371 {
372 inflateEnd(z);
373 return Z_MEM_ERROR;
374 }
375 Trace((stderr, "inflate: allocated\n"));
376
377 /* reset state */
378 inflateReset(z);
379 return Z_OK;
380 }
381
382
383 int inflateInit(z)
384 z_stream *z;
385 {
386 return inflateInit2(z, DEF_WBITS);
387 }
388
389
390 #define NEEDBYTE {if(z->avail_in==0)goto empty;r=Z_OK;}
391 #define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++)
392
393 int inflate(z, f)
394 z_stream *z;
395 int f;
396 {
397 int r;
398 uInt b;
399
400 if (z == Z_NULL || z->next_in == Z_NULL)
401 return Z_STREAM_ERROR;
402 r = Z_BUF_ERROR;
403 while (1) switch (z->state->mode)
404 {
405 case METHOD:
406 NEEDBYTE
407 if (((z->state->sub.method = NEXTBYTE) & 0xf) != DEFLATED)
408 {
409 z->state->mode = BAD;
410 z->msg = "unknown compression method";
411 z->state->sub.marker = 5; /* can't try inflateSync */
412 break;
413 }
414 if ((z->state->sub.method >> 4) + 8 > z->state->wbits)
415 {
416 z->state->mode = BAD;
417 z->msg = "invalid window size";
418 z->state->sub.marker = 5; /* can't try inflateSync */
419 break;
420 }
421 z->state->mode = FLAG;
422 case FLAG:
423 NEEDBYTE
424 if ((b = NEXTBYTE) & 0x20)
425 {
426 z->state->mode = BAD;
427 z->msg = "invalid reserved bit";
428 z->state->sub.marker = 5; /* can't try inflateSync */
429 break;
430 }
431 if (((z->state->sub.method << 8) + b) % 31)
432 {
433 z->state->mode = BAD;
434 z->msg = "incorrect header check";
435 z->state->sub.marker = 5; /* can't try inflateSync */
436 break;
437 }
438 Trace((stderr, "inflate: zlib header ok\n"));
439 z->state->mode = BLOCKS;
440 case BLOCKS:
441 r = inflate_blocks(z->state->blocks, z, r);
442 if (f == Z_PACKET_FLUSH && z->avail_in == 0 && z->avail_out != 0)
443 r = inflate_packet_flush(z->state->blocks);
444 if (r == Z_DATA_ERROR)
445 {
446 z->state->mode = BAD;
447 z->state->sub.marker = 0; /* can try inflateSync */
448 break;
449 }
450 if (r != Z_STREAM_END)
451 return r;
452 r = Z_OK;
453 inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was);
454 if (z->state->nowrap)
455 {
456 z->state->mode = DONE;
457 break;
458 }
459 z->state->mode = CHECK4;
460 case CHECK4:
461 NEEDBYTE
462 z->state->sub.check.need = (uLong)NEXTBYTE << 24;
463 z->state->mode = CHECK3;
464 case CHECK3:
465 NEEDBYTE
466 z->state->sub.check.need += (uLong)NEXTBYTE << 16;
467 z->state->mode = CHECK2;
468 case CHECK2:
469 NEEDBYTE
470 z->state->sub.check.need += (uLong)NEXTBYTE << 8;
471 z->state->mode = CHECK1;
472 case CHECK1:
473 NEEDBYTE
474 z->state->sub.check.need += (uLong)NEXTBYTE;
475
476 if (z->state->sub.check.was != z->state->sub.check.need)
477 {
478 z->state->mode = BAD;
479 z->msg = "incorrect data check";
480 z->state->sub.marker = 5; /* can't try inflateSync */
481 break;
482 }
483 Trace((stderr, "inflate: zlib check ok\n"));
484 z->state->mode = DONE;
485 case DONE:
486 return Z_STREAM_END;
487 case BAD:
488 return Z_DATA_ERROR;
489 default:
490 return Z_STREAM_ERROR;
491 }
492
493 empty:
494 if (f != Z_PACKET_FLUSH)
495 return r;
496 z->state->mode = BAD;
497 z->state->sub.marker = 0; /* can try inflateSync */
498 return Z_DATA_ERROR;
499 }
500
501 /*
502 * This subroutine adds the data at next_in/avail_in to the output history
503 * without performing any output. The output buffer must be "caught up";
504 * i.e. no pending output (hence s->read equals s->write), and the state must
505 * be BLOCKS (i.e. we should be willing to see the start of a series of
506 * BLOCKS). On exit, the output will also be caught up, and the checksum
507 * will have been updated if need be.
508 */
509
510 int inflateIncomp(z)
511 z_stream *z;
512 {
513 if (z->state->mode != BLOCKS)
514 return Z_DATA_ERROR;
515 return inflate_addhistory(z->state->blocks, z);
516 }
517
518
519 int inflateSync(z)
520 z_stream *z;
521 {
522 uInt n; /* number of bytes to look at */
523 Bytef *p; /* pointer to bytes */
524 uInt m; /* number of marker bytes found in a row */
525 uLong r, w; /* temporaries to save total_in and total_out */
526
527 /* set up */
528 if (z == Z_NULL || z->state == Z_NULL)
529 return Z_STREAM_ERROR;
530 if (z->state->mode != BAD)
531 {
532 z->state->mode = BAD;
533 z->state->sub.marker = 0;
534 }
535 if ((n = z->avail_in) == 0)
536 return Z_BUF_ERROR;
537 p = z->next_in;
538 m = z->state->sub.marker;
539
540 /* search */
541 while (n && m < 4)
542 {
543 if (*p == (Byte)(m < 2 ? 0 : 0xff))
544 m++;
545 else if (*p)
546 m = 0;
547 else
548 m = 4 - m;
549 p++, n--;
550 }
551
552 /* restore */
553 z->total_in += p - z->next_in;
554 z->next_in = p;
555 z->avail_in = n;
556 z->state->sub.marker = m;
557
558 /* return no joy or set up to restart on a new block */
559 if (m != 4)
560 return Z_DATA_ERROR;
561 r = z->total_in; w = z->total_out;
562 inflateReset(z);
563 z->total_in = r; z->total_out = w;
564 z->state->mode = BLOCKS;
565 return Z_OK;
566 }
567
568 #undef NEEDBYTE
569 #undef NEXTBYTE
570
571 /*+++++*/
572 /* infutil.h -- types and macros common to blocks and codes
573 * Copyright (C) 1995 Mark Adler
574 * For conditions of distribution and use, see copyright notice in zlib.h
575 */
576
577 /* WARNING: this file should *not* be used by applications. It is
578 part of the implementation of the compression library and is
579 subject to change. Applications should only use zlib.h.
580 */
581
582 /* inflate blocks semi-private state */
583 struct inflate_blocks_state {
584
585 /* mode */
586 enum {
587 TYPE, /* get type bits (3, including end bit) */
588 LENS, /* get lengths for stored */
589 STORED, /* processing stored block */
590 TABLE, /* get table lengths */
591 BTREE, /* get bit lengths tree for a dynamic block */
592 DTREE, /* get length, distance trees for a dynamic block */
593 CODES, /* processing fixed or dynamic block */
594 DRY, /* output remaining window bytes */
595 DONEB, /* finished last block, done */
596 BADB} /* got a data error--stuck here */
597 mode; /* current inflate_block mode */
598
599 /* mode dependent information */
600 union {
601 uInt left; /* if STORED, bytes left to copy */
602 struct {
603 uInt table; /* table lengths (14 bits) */
604 uInt index; /* index into blens (or border) */
605 uIntf *blens; /* bit lengths of codes */
606 uInt bb; /* bit length tree depth */
607 inflate_huft *tb; /* bit length decoding tree */
608 int nblens; /* # elements allocated at blens */
609 } trees; /* if DTREE, decoding info for trees */
610 struct {
611 inflate_huft *tl, *td; /* trees to free */
612 inflate_codes_statef
613 *codes;
614 } decode; /* if CODES, current state */
615 } sub; /* submode */
616 uInt last; /* true if this block is the last block */
617
618 /* mode independent information */
619 uInt bitk; /* bits in bit buffer */
620 uLong bitb; /* bit buffer */
621 Bytef *window; /* sliding window */
622 Bytef *end; /* one byte after sliding window */
623 Bytef *read; /* window read pointer */
624 Bytef *write; /* window write pointer */
625 check_func checkfn; /* check function */
626 uLong check; /* check on output */
627
628 };
629
630
631 /* defines for inflate input/output */
632 /* update pointers and return */
633 #define UPDBITS {s->bitb=b;s->bitk=k;}
634 #define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;}
635 #define UPDOUT {s->write=q;}
636 #define UPDATE {UPDBITS UPDIN UPDOUT}
637 #define LEAVE {UPDATE return inflate_flush(s,z,r);}
638 /* get bytes and bits */
639 #define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;}
640 #define NEEDBYTE {if(n)r=Z_OK;else LEAVE}
641 #define NEXTBYTE (n--,*p++)
642 #define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}}
643 #define DUMPBITS(j) {b>>=(j);k-=(j);}
644 /* output bytes */
645 #define WAVAIL (q<s->read?s->read-q-1:s->end-q)
646 #define LOADOUT {q=s->write;m=WAVAIL;}
647 #define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=WAVAIL;}}
648 #define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT}
649 #define NEEDOUT {if(m==0){WRAP if(m==0){FLUSH WRAP if(m==0) LEAVE}}r=Z_OK;}
650 #define OUTBYTE(a) {*q++=(Byte)(a);m--;}
651 /* load local pointers */
652 #define LOAD {LOADIN LOADOUT}
653
654 /*
655 * The IBM 150 firmware munges the data right after _etext[]. This
656 * protects it. -- Cort
657 */
658 local uInt protect_mask[] = {0, 0, 0, 0, 0, 0, 0, 0, 0 ,0 ,0 ,0};
659 /* And'ing with mask[n] masks the lower n bits */
660 local uInt inflate_mask[] = {
661 0x0000,
662 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
663 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
664 };
665
666 /* copy as much as possible from the sliding window to the output area */
667 local int inflate_flush OF((
668 inflate_blocks_statef *,
669 z_stream *,
670 int));
671
672 /*+++++*/
673 /* inffast.h -- header to use inffast.c
674 * Copyright (C) 1995 Mark Adler
675 * For conditions of distribution and use, see copyright notice in zlib.h
676 */
677
678 /* WARNING: this file should *not* be used by applications. It is
679 part of the implementation of the compression library and is
680 subject to change. Applications should only use zlib.h.
681 */
682
683 local int inflate_fast OF((
684 uInt,
685 uInt,
686 inflate_huft *,
687 inflate_huft *,
688 inflate_blocks_statef *,
689 z_stream *));
690
691
692 /*+++++*/
693 /* infblock.c -- interpret and process block types to last block
694 * Copyright (C) 1995 Mark Adler
695 * For conditions of distribution and use, see copyright notice in zlib.h
696 */
697
698 /* Table for deflate from PKZIP's appnote.txt. */
699 local uInt border[] = { /* Order of the bit length code lengths */
700 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
701
702 /*
703 Notes beyond the 1.93a appnote.txt:
704
705 1. Distance pointers never point before the beginning of the output
706 stream.
707 2. Distance pointers can point back across blocks, up to 32k away.
708 3. There is an implied maximum of 7 bits for the bit length table and
709 15 bits for the actual data.
710 4. If only one code exists, then it is encoded using one bit. (Zero
711 would be more efficient, but perhaps a little confusing.) If two
712 codes exist, they are coded using one bit each (0 and 1).
713 5. There is no way of sending zero distance codes--a dummy must be
714 sent if there are none. (History: a pre 2.0 version of PKZIP would
715 store blocks with no distance codes, but this was discovered to be
716 too harsh a criterion.) Valid only for 1.93a. 2.04c does allow
717 zero distance codes, which is sent as one code of zero bits in
718 length.
719 6. There are up to 286 literal/length codes. Code 256 represents the
720 end-of-block. Note however that the static length tree defines
721 288 codes just to fill out the Huffman codes. Codes 286 and 287
722 cannot be used though, since there is no length base or extra bits
723 defined for them. Similarily, there are up to 30 distance codes.
724 However, static trees define 32 codes (all 5 bits) to fill out the
725 Huffman codes, but the last two had better not show up in the data.
726 7. Unzip can check dynamic Huffman blocks for complete code sets.
727 The exception is that a single code would not be complete (see #4).
728 8. The five bits following the block type is really the number of
729 literal codes sent minus 257.
730 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
731 (1+6+6). Therefore, to output three times the length, you output
732 three codes (1+1+1), whereas to output four times the same length,
733 you only need two codes (1+3). Hmm.
734 10. In the tree reconstruction algorithm, Code = Code + Increment
735 only if BitLength(i) is not zero. (Pretty obvious.)
736 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19)
737 12. Note: length code 284 can represent 227-258, but length code 285
738 really is 258. The last length deserves its own, short code
739 since it gets used a lot in very redundant files. The length
740 258 is special since 258 - 3 (the min match length) is 255.
741 13. The literal/length and distance code bit lengths are read as a
742 single stream of lengths. It is possible (and advantageous) for
743 a repeat code (16, 17, or 18) to go across the boundary between
744 the two sets of lengths.
745 */
746
747
748 local void inflate_blocks_reset(s, z, c)
749 inflate_blocks_statef *s;
750 z_stream *z;
751 uLongf *c;
752 {
753 if (s->checkfn != Z_NULL)
754 *c = s->check;
755 if (s->mode == BTREE || s->mode == DTREE)
756 ZFREE(z, s->sub.trees.blens, s->sub.trees.nblens * sizeof(uInt));
757 if (s->mode == CODES)
758 {
759 inflate_codes_free(s->sub.decode.codes, z);
760 inflate_trees_free(s->sub.decode.td, z);
761 inflate_trees_free(s->sub.decode.tl, z);
762 }
763 s->mode = TYPE;
764 s->bitk = 0;
765 s->bitb = 0;
766 s->read = s->write = s->window;
767 if (s->checkfn != Z_NULL)
768 s->check = (*s->checkfn)(0L, Z_NULL, 0);
769 Trace((stderr, "inflate: blocks reset\n"));
770 }
771
772
773 local inflate_blocks_statef *inflate_blocks_new(z, c, w)
774 z_stream *z;
775 check_func c;
776 uInt w;
777 {
778 inflate_blocks_statef *s;
779
780 if ((s = (inflate_blocks_statef *)ZALLOC
781 (z,1,sizeof(struct inflate_blocks_state))) == Z_NULL)
782 return s;
783 if ((s->window = (Bytef *)ZALLOC(z, 1, w)) == Z_NULL)
784 {
785 ZFREE(z, s, sizeof(struct inflate_blocks_state));
786 return Z_NULL;
787 }
788 s->end = s->window + w;
789 s->checkfn = c;
790 s->mode = TYPE;
791 Trace((stderr, "inflate: blocks allocated\n"));
792 inflate_blocks_reset(s, z, &s->check);
793 return s;
794 }
795
796
797 local int inflate_blocks(s, z, r)
798 inflate_blocks_statef *s;
799 z_stream *z;
800 int r;
801 {
802 uInt t; /* temporary storage */
803 uLong b; /* bit buffer */
804 uInt k; /* bits in bit buffer */
805 Bytef *p; /* input data pointer */
806 uInt n; /* bytes available there */
807 Bytef *q; /* output window write pointer */
808 uInt m; /* bytes to end of window or read pointer */
809
810 /* copy input/output information to locals (UPDATE macro restores) */
811 LOAD
812
813 /* process input based on current state */
814 while (1) switch (s->mode)
815 {
816 case TYPE:
817 NEEDBITS(3)
818 t = (uInt)b & 7;
819 s->last = t & 1;
820 switch (t >> 1)
821 {
822 case 0: /* stored */
823 Trace((stderr, "inflate: stored block%s\n",
824 s->last ? " (last)" : ""));
825 DUMPBITS(3)
826 t = k & 7; /* go to byte boundary */
827 DUMPBITS(t)
828 s->mode = LENS; /* get length of stored block */
829 break;
830 case 1: /* fixed */
831 Trace((stderr, "inflate: fixed codes block%s\n",
832 s->last ? " (last)" : ""));
833 {
834 uInt bl, bd;
835 inflate_huft *tl, *td;
836
837 inflate_trees_fixed(&bl, &bd, &tl, &td);
838 s->sub.decode.codes = inflate_codes_new(bl, bd, tl, td, z);
839 if (s->sub.decode.codes == Z_NULL)
840 {
841 r = Z_MEM_ERROR;
842 LEAVE
843 }
844 s->sub.decode.tl = Z_NULL; /* don't try to free these */
845 s->sub.decode.td = Z_NULL;
846 }
847 DUMPBITS(3)
848 s->mode = CODES;
849 break;
850 case 2: /* dynamic */
851 Trace((stderr, "inflate: dynamic codes block%s\n",
852 s->last ? " (last)" : ""));
853 DUMPBITS(3)
854 s->mode = TABLE;
855 break;
856 case 3: /* illegal */
857 DUMPBITS(3)
858 s->mode = BADB;
859 z->msg = "invalid block type";
860 r = Z_DATA_ERROR;
861 LEAVE
862 }
863 break;
864 case LENS:
865 NEEDBITS(32)
866 if (((~b) >> 16) != (b & 0xffff))
867 {
868 s->mode = BADB;
869 z->msg = "invalid stored block lengths";
870 r = Z_DATA_ERROR;
871 LEAVE
872 }
873 s->sub.left = (uInt)b & 0xffff;
874 b = k = 0; /* dump bits */
875 Tracev((stderr, "inflate: stored length %u\n", s->sub.left));
876 s->mode = s->sub.left ? STORED : TYPE;
877 break;
878 case STORED:
879 if (n == 0)
880 LEAVE
881 NEEDOUT
882 t = s->sub.left;
883 if (t > n) t = n;
884 if (t > m) t = m;
885 zmemcpy(q, p, t);
886 p += t; n -= t;
887 q += t; m -= t;
888 if ((s->sub.left -= t) != 0)
889 break;
890 Tracev((stderr, "inflate: stored end, %lu total out\n",
891 z->total_out + (q >= s->read ? q - s->read :
892 (s->end - s->read) + (q - s->window))));
893 s->mode = s->last ? DRY : TYPE;
894 break;
895 case TABLE:
896 NEEDBITS(14)
897 s->sub.trees.table = t = (uInt)b & 0x3fff;
898 #ifndef PKZIP_BUG_WORKAROUND
899 if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29)
900 {
901 s->mode = BADB;
902 z->msg = "too many length or distance symbols";
903 r = Z_DATA_ERROR;
904 LEAVE
905 }
906 #endif
907 t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
908 if (t < 19)
909 t = 19;
910 if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL)
911 {
912 r = Z_MEM_ERROR;
913 LEAVE
914 }
915 s->sub.trees.nblens = t;
916 DUMPBITS(14)
917 s->sub.trees.index = 0;
918 Tracev((stderr, "inflate: table sizes ok\n"));
919 s->mode = BTREE;
920 case BTREE:
921 while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10))
922 {
923 NEEDBITS(3)
924 s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7;
925 DUMPBITS(3)
926 }
927 while (s->sub.trees.index < 19)
928 s->sub.trees.blens[border[s->sub.trees.index++]] = 0;
929 s->sub.trees.bb = 7;
930 t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb,
931 &s->sub.trees.tb, z);
932 if (t != Z_OK)
933 {
934 r = t;
935 if (r == Z_DATA_ERROR)
936 s->mode = BADB;
937 LEAVE
938 }
939 s->sub.trees.index = 0;
940 Tracev((stderr, "inflate: bits tree ok\n"));
941 s->mode = DTREE;
942 case DTREE:
943 while (t = s->sub.trees.table,
944 s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f))
945 {
946 inflate_huft *h;
947 uInt i, j, c;
948
949 t = s->sub.trees.bb;
950 NEEDBITS(t)
951 h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]);
952 t = h->word.what.Bits;
953 c = h->more.Base;
954 if (c < 16)
955 {
956 DUMPBITS(t)
957 s->sub.trees.blens[s->sub.trees.index++] = c;
958 }
959 else /* c == 16..18 */
960 {
961 i = c == 18 ? 7 : c - 14;
962 j = c == 18 ? 11 : 3;
963 NEEDBITS(t + i)
964 DUMPBITS(t)
965 j += (uInt)b & inflate_mask[i];
966 DUMPBITS(i)
967 i = s->sub.trees.index;
968 t = s->sub.trees.table;
969 if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) ||
970 (c == 16 && i < 1))
971 {
972 s->mode = BADB;
973 z->msg = "invalid bit length repeat";
974 r = Z_DATA_ERROR;
975 LEAVE
976 }
977 c = c == 16 ? s->sub.trees.blens[i - 1] : 0;
978 do {
979 s->sub.trees.blens[i++] = c;
980 } while (--j);
981 s->sub.trees.index = i;
982 }
983 }
984 inflate_trees_free(s->sub.trees.tb, z);
985 s->sub.trees.tb = Z_NULL;
986 {
987 uInt bl, bd;
988 inflate_huft *tl, *td;
989 inflate_codes_statef *c;
990
991 bl = 9; /* must be <= 9 for lookahead assumptions */
992 bd = 6; /* must be <= 9 for lookahead assumptions */
993 t = s->sub.trees.table;
994 t = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f),
995 s->sub.trees.blens, &bl, &bd, &tl, &td, z);
996 if (t != Z_OK)
997 {
998 if (t == (uInt)Z_DATA_ERROR)
999 s->mode = BADB;
1000 r = t;
1001 LEAVE
1002 }
1003 Tracev((stderr, "inflate: trees ok\n"));
1004 if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL)
1005 {
1006 inflate_trees_free(td, z);
1007 inflate_trees_free(tl, z);
1008 r = Z_MEM_ERROR;
1009 LEAVE
1010 }
1011 ZFREE(z, s->sub.trees.blens, s->sub.trees.nblens * sizeof(uInt));
1012 s->sub.decode.codes = c;
1013 s->sub.decode.tl = tl;
1014 s->sub.decode.td = td;
1015 }
1016 s->mode = CODES;
1017 case CODES:
1018 UPDATE
1019 if ((r = inflate_codes(s, z, r)) != Z_STREAM_END)
1020 return inflate_flush(s, z, r);
1021 r = Z_OK;
1022 inflate_codes_free(s->sub.decode.codes, z);
1023 inflate_trees_free(s->sub.decode.td, z);
1024 inflate_trees_free(s->sub.decode.tl, z);
1025 LOAD
1026 Tracev((stderr, "inflate: codes end, %lu total out\n",
1027 z->total_out + (q >= s->read ? q - s->read :
1028 (s->end - s->read) + (q - s->window))));
1029 if (!s->last)
1030 {
1031 s->mode = TYPE;
1032 break;
1033 }
1034 if (k > 7) /* return unused byte, if any */
1035 {
1036 Assert(k < 16, "inflate_codes grabbed too many bytes")
1037 k -= 8;
1038 n++;
1039 p--; /* can always return one */
1040 }
1041 s->mode = DRY;
1042 case DRY:
1043 FLUSH
1044 if (s->read != s->write)
1045 LEAVE
1046 s->mode = DONEB;
1047 case DONEB:
1048 r = Z_STREAM_END;
1049 LEAVE
1050 case BADB:
1051 r = Z_DATA_ERROR;
1052 LEAVE
1053 default:
1054 r = Z_STREAM_ERROR;
1055 LEAVE
1056 }
1057 }
1058
1059
1060 local int inflate_blocks_free(s, z, c)
1061 inflate_blocks_statef *s;
1062 z_stream *z;
1063 uLongf *c;
1064 {
1065 inflate_blocks_reset(s, z, c);
1066 ZFREE(z, s->window, s->end - s->window);
1067 ZFREE(z, s, sizeof(struct inflate_blocks_state));
1068 Trace((stderr, "inflate: blocks freed\n"));
1069 return Z_OK;
1070 }
1071
1072 /*
1073 * This subroutine adds the data at next_in/avail_in to the output history
1074 * without performing any output. The output buffer must be "caught up";
1075 * i.e. no pending output (hence s->read equals s->write), and the state must
1076 * be BLOCKS (i.e. we should be willing to see the start of a series of
1077 * BLOCKS). On exit, the output will also be caught up, and the checksum
1078 * will have been updated if need be.
1079 */
1080 local int inflate_addhistory(s, z)
1081 inflate_blocks_statef *s;
1082 z_stream *z;
1083 {
1084 uLong b; /* bit buffer */ /* NOT USED HERE */
1085 uInt k; /* bits in bit buffer */ /* NOT USED HERE */
1086 uInt t; /* temporary storage */
1087 Bytef *p; /* input data pointer */
1088 uInt n; /* bytes available there */
1089 Bytef *q; /* output window write pointer */
1090 uInt m; /* bytes to end of window or read pointer */
1091
1092 if (s->read != s->write)
1093 return Z_STREAM_ERROR;
1094 if (s->mode != TYPE)
1095 return Z_DATA_ERROR;
1096
1097 /* we're ready to rock */
1098 LOAD
1099 /* while there is input ready, copy to output buffer, moving
1100 * pointers as needed.
1101 */
1102 while (n) {
1103 t = n; /* how many to do */
1104 /* is there room until end of buffer? */
1105 if (t > m) t = m;
1106 /* update check information */
1107 if (s->checkfn != Z_NULL)
1108 s->check = (*s->checkfn)(s->check, q, t);
1109 zmemcpy(q, p, t);
1110 q += t;
1111 p += t;
1112 n -= t;
1113 z->total_out += t;
1114 s->read = q; /* drag read pointer forward */
1115 /* WRAP */ /* expand WRAP macro by hand to handle s->read */
1116 if (q == s->end) {
1117 s->read = q = s->window;
1118 m = WAVAIL;
1119 }
1120 }
1121 UPDATE
1122 return Z_OK;
1123 }
1124
1125
1126 /*
1127 * At the end of a Deflate-compressed PPP packet, we expect to have seen
1128 * a `stored' block type value but not the (zero) length bytes.
1129 */
1130 local int inflate_packet_flush(s)
1131 inflate_blocks_statef *s;
1132 {
1133 if (s->mode != LENS)
1134 return Z_DATA_ERROR;
1135 s->mode = TYPE;
1136 return Z_OK;
1137 }
1138
1139
1140 /*+++++*/
1141 /* inftrees.c -- generate Huffman trees for efficient decoding
1142 * Copyright (C) 1995 Mark Adler
1143 * For conditions of distribution and use, see copyright notice in zlib.h
1144 */
1145
1146 /* simplify the use of the inflate_huft type with some defines */
1147 #define base more.Base
1148 #define next more.Next
1149 #define exop word.what.Exop
1150 #define bits word.what.Bits
1151
1152
1153 local int huft_build OF((
1154 uIntf *, /* code lengths in bits */
1155 uInt, /* number of codes */
1156 uInt, /* number of "simple" codes */
1157 uIntf *, /* list of base values for non-simple codes */
1158 uIntf *, /* list of extra bits for non-simple codes */
1159 inflate_huft * FAR*,/* result: starting table */
1160 uIntf *, /* maximum lookup bits (returns actual) */
1161 z_stream *)); /* for zalloc function */
1162
1163 local voidpf falloc OF((
1164 voidpf, /* opaque pointer (not used) */
1165 uInt, /* number of items */
1166 uInt)); /* size of item */
1167
1168 local void ffree OF((
1169 voidpf q, /* opaque pointer (not used) */
1170 voidpf p, /* what to free (not used) */
1171 uInt n)); /* number of bytes (not used) */
1172
1173 /* Tables for deflate from PKZIP's appnote.txt. */
1174 local uInt cplens[] = { /* Copy lengths for literal codes 257..285 */
1175 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
1176 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
1177 /* actually lengths - 2; also see note #13 above about 258 */
1178 local uInt cplext[] = { /* Extra bits for literal codes 257..285 */
1179 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
1180 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 192, 192}; /* 192==invalid */
1181 local uInt cpdist[] = { /* Copy offsets for distance codes 0..29 */
1182 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
1183 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
1184 8193, 12289, 16385, 24577};
1185 local uInt cpdext[] = { /* Extra bits for distance codes */
1186 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
1187 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
1188 12, 12, 13, 13};
1189
1190 /*
1191 Huffman code decoding is performed using a multi-level table lookup.
1192 The fastest way to decode is to simply build a lookup table whose
1193 size is determined by the longest code. However, the time it takes
1194 to build this table can also be a factor if the data being decoded
1195 is not very long. The most common codes are necessarily the
1196 shortest codes, so those codes dominate the decoding time, and hence
1197 the speed. The idea is you can have a shorter table that decodes the
1198 shorter, more probable codes, and then point to subsidiary tables for
1199 the longer codes. The time it costs to decode the longer codes is
1200 then traded against the time it takes to make longer tables.
1201
1202 This results of this trade are in the variables lbits and dbits
1203 below. lbits is the number of bits the first level table for literal/
1204 length codes can decode in one step, and dbits is the same thing for
1205 the distance codes. Subsequent tables are also less than or equal to
1206 those sizes. These values may be adjusted either when all of the
1207 codes are shorter than that, in which case the longest code length in
1208 bits is used, or when the shortest code is *longer* than the requested
1209 table size, in which case the length of the shortest code in bits is
1210 used.
1211
1212 There are two different values for the two tables, since they code a
1213 different number of possibilities each. The literal/length table
1214 codes 286 possible values, or in a flat code, a little over eight
1215 bits. The distance table codes 30 possible values, or a little less
1216 than five bits, flat. The optimum values for speed end up being
1217 about one bit more than those, so lbits is 8+1 and dbits is 5+1.
1218 The optimum values may differ though from machine to machine, and
1219 possibly even between compilers. Your mileage may vary.
1220 */
1221
1222
1223 /* If BMAX needs to be larger than 16, then h and x[] should be uLong. */
1224 #define BMAX 15 /* maximum bit length of any code */
1225 #define N_MAX 288 /* maximum number of codes in any set */
1226
1227 #ifdef DEBUG_ZLIB
1228 uInt inflate_hufts;
1229 #endif
1230
1231 local int huft_build(b, n, s, d, e, t, m, zs)
1232 uIntf *b; /* code lengths in bits (all assumed <= BMAX) */
1233 uInt n; /* number of codes (assumed <= N_MAX) */
1234 uInt s; /* number of simple-valued codes (0..s-1) */
1235 uIntf *d; /* list of base values for non-simple codes */
1236 uIntf *e; /* list of extra bits for non-simple codes */
1237 inflate_huft * FAR *t; /* result: starting table */
1238 uIntf *m; /* maximum lookup bits, returns actual */
1239 z_stream *zs; /* for zalloc function */
1240 /* Given a list of code lengths and a maximum table size, make a set of
1241 tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR
1242 if the given code set is incomplete (the tables are still built in this
1243 case), Z_DATA_ERROR if the input is invalid (all zero length codes or an
1244 over-subscribed set of lengths), or Z_MEM_ERROR if not enough memory. */
1245 {
1246
1247 uInt a; /* counter for codes of length k */
1248 uInt c[BMAX+1]; /* bit length count table */
1249 uInt f; /* i repeats in table every f entries */
1250 int g; /* maximum code length */
1251 int h; /* table level */
1252 register uInt i; /* counter, current code */
1253 register uInt j; /* counter */
1254 register int k; /* number of bits in current code */
1255 int l; /* bits per table (returned in m) */
1256 register uIntf *p; /* pointer into c[], b[], or v[] */
1257 inflate_huft *q; /* points to current table */
1258 struct inflate_huft_s r; /* table entry for structure assignment */
1259 inflate_huft *u[BMAX]; /* table stack */
1260 uInt v[N_MAX]; /* values in order of bit length */
1261 register int w; /* bits before this table == (l * h) */
1262 uInt x[BMAX+1]; /* bit offsets, then code stack */
1263 uIntf *xp; /* pointer into x */
1264 int y; /* number of dummy codes added */
1265 uInt z; /* number of entries in current table */
1266
1267
1268 /* Generate counts for each bit length */
1269 p = c;
1270 #define C0 *p++ = 0;
1271 #define C2 C0 C0 C0 C0
1272 #define C4 C2 C2 C2 C2
1273 C4 /* clear c[]--assume BMAX+1 is 16 */
1274 p = b; i = n;
1275 do {
1276 c[*p++]++; /* assume all entries <= BMAX */
1277 } while (--i);
1278 if (c[0] == n) /* null input--all zero length codes */
1279 {
1280 *t = (inflate_huft *)Z_NULL;
1281 *m = 0;
1282 return Z_OK;
1283 }
1284
1285
1286 /* Find minimum and maximum length, bound *m by those */
1287 l = *m;
1288 for (j = 1; j <= BMAX; j++)
1289 if (c[j])
1290 break;
1291 k = j; /* minimum code length */
1292 if ((uInt)l < j)
1293 l = j;
1294 for (i = BMAX; i; i--)
1295 if (c[i])
1296 break;
1297 g = i; /* maximum code length */
1298 if ((uInt)l > i)
1299 l = i;
1300 *m = l;
1301
1302
1303 /* Adjust last length count to fill out codes, if needed */
1304 for (y = 1 << j; j < i; j++, y <<= 1)
1305 if ((y -= c[j]) < 0)
1306 return Z_DATA_ERROR;
1307 if ((y -= c[i]) < 0)
1308 return Z_DATA_ERROR;
1309 c[i] += y;
1310
1311
1312 /* Generate starting offsets into the value table for each length */
1313 x[1] = j = 0;
1314 p = c + 1; xp = x + 2;
1315 while (--i) { /* note that i == g from above */
1316 *xp++ = (j += *p++);
1317 }
1318
1319
1320 /* Make a table of values in order of bit lengths */
1321 p = b; i = 0;
1322 do {
1323 if ((j = *p++) != 0)
1324 v[x[j]++] = i;
1325 } while (++i < n);
1326
1327
1328 /* Generate the Huffman codes and for each, make the table entries */
1329 x[0] = i = 0; /* first Huffman code is zero */
1330 p = v; /* grab values in bit order */
1331 h = -1; /* no tables yet--level -1 */
1332 w = -l; /* bits decoded == (l * h) */
1333 u[0] = (inflate_huft *)Z_NULL; /* just to keep compilers happy */
1334 q = (inflate_huft *)Z_NULL; /* ditto */
1335 z = 0; /* ditto */
1336
1337 /* go through the bit lengths (k already is bits in shortest code) */
1338 for (; k <= g; k++)
1339 {
1340 a = c[k];
1341 while (a--)
1342 {
1343 /* here i is the Huffman code of length k bits for value *p */
1344 /* make tables up to required level */
1345 while (k > w + l)
1346 {
1347 h++;
1348 w += l; /* previous table always l bits */
1349
1350 /* compute minimum size table less than or equal to l bits */
1351 z = (z = g - w) > (uInt)l ? l : z; /* table size upper limit */
1352 if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */
1353 { /* too few codes for k-w bit table */
1354 f -= a + 1; /* deduct codes from patterns left */
1355 xp = c + k;
1356 if (j < z)
1357 while (++j < z) /* try smaller tables up to z bits */
1358 {
1359 if ((f <<= 1) <= *++xp)
1360 break; /* enough codes to use up j bits */
1361 f -= *xp; /* else deduct codes from patterns */
1362 }
1363 }
1364 z = 1 << j; /* table entries for j-bit table */
1365
1366 /* allocate and link in new table */
1367 if ((q = (inflate_huft *)ZALLOC
1368 (zs,z + 1,sizeof(inflate_huft))) == Z_NULL)
1369 {
1370 if (h)
1371 inflate_trees_free(u[0], zs);
1372 return Z_MEM_ERROR; /* not enough memory */
1373 }
1374 q->word.Nalloc = z + 1;
1375 #ifdef DEBUG_ZLIB
1376 inflate_hufts += z + 1;
1377 #endif
1378 *t = q + 1; /* link to list for huft_free() */
1379 *(t = &(q->next)) = Z_NULL;
1380 u[h] = ++q; /* table starts after link */
1381
1382 /* connect to last table, if there is one */
1383 if (h)
1384 {
1385 x[h] = i; /* save pattern for backing up */
1386 r.bits = (Byte)l; /* bits to dump before this table */
1387 r.exop = (Byte)j; /* bits in this table */
1388 r.next = q; /* pointer to this table */
1389 j = i >> (w - l); /* (get around Turbo C bug) */
1390 u[h-1][j] = r; /* connect to last table */
1391 }
1392 }
1393
1394 /* set up table entry in r */
1395 r.bits = (Byte)(k - w);
1396 if (p >= v + n)
1397 r.exop = 128 + 64; /* out of values--invalid code */
1398 else if (*p < s)
1399 {
1400 r.exop = (Byte)(*p < 256 ? 0 : 32 + 64); /* 256 is end-of-block */
1401 r.base = *p++; /* simple code is just the value */
1402 }
1403 else
1404 {
1405 r.exop = (Byte)e[*p - s] + 16 + 64; /* non-simple--look up in lists */
1406 r.base = d[*p++ - s];
1407 }
1408
1409 /* fill code-like entries with r */
1410 f = 1 << (k - w);
1411 for (j = i >> w; j < z; j += f)
1412 q[j] = r;
1413
1414 /* backwards increment the k-bit code i */
1415 for (j = 1 << (k - 1); i & j; j >>= 1)
1416 i ^= j;
1417 i ^= j;
1418
1419 /* backup over finished tables */
1420 while ((i & ((1 << w) - 1)) != x[h])
1421 {
1422 h--; /* don't need to update q */
1423 w -= l;
1424 }
1425 }
1426 }
1427
1428
1429 /* Return Z_BUF_ERROR if we were given an incomplete table */
1430 return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK;
1431 }
1432
1433
1434 local int inflate_trees_bits(c, bb, tb, z)
1435 uIntf *c; /* 19 code lengths */
1436 uIntf *bb; /* bits tree desired/actual depth */
1437 inflate_huft * FAR *tb; /* bits tree result */
1438 z_stream *z; /* for zfree function */
1439 {
1440 int r;
1441
1442 r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL, tb, bb, z);
1443 if (r == Z_DATA_ERROR)
1444 z->msg = "oversubscribed dynamic bit lengths tree";
1445 else if (r == Z_BUF_ERROR)
1446 {
1447 inflate_trees_free(*tb, z);
1448 z->msg = "incomplete dynamic bit lengths tree";
1449 r = Z_DATA_ERROR;
1450 }
1451 return r;
1452 }
1453
1454
1455 local int inflate_trees_dynamic(nl, nd, c, bl, bd, tl, td, z)
1456 uInt nl; /* number of literal/length codes */
1457 uInt nd; /* number of distance codes */
1458 uIntf *c; /* that many (total) code lengths */
1459 uIntf *bl; /* literal desired/actual bit depth */
1460 uIntf *bd; /* distance desired/actual bit depth */
1461 inflate_huft * FAR *tl; /* literal/length tree result */
1462 inflate_huft * FAR *td; /* distance tree result */
1463 z_stream *z; /* for zfree function */
1464 {
1465 int r;
1466
1467 /* build literal/length tree */
1468 if ((r = huft_build(c, nl, 257, cplens, cplext, tl, bl, z)) != Z_OK)
1469 {
1470 if (r == Z_DATA_ERROR)
1471 z->msg = "oversubscribed literal/length tree";
1472 else if (r == Z_BUF_ERROR)
1473 {
1474 inflate_trees_free(*tl, z);
1475 z->msg = "incomplete literal/length tree";
1476 r = Z_DATA_ERROR;
1477 }
1478 return r;
1479 }
1480
1481 /* build distance tree */
1482 if ((r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, z)) != Z_OK)
1483 {
1484 if (r == Z_DATA_ERROR)
1485 z->msg = "oversubscribed literal/length tree";
1486 else if (r == Z_BUF_ERROR) {
1487 #ifdef PKZIP_BUG_WORKAROUND
1488 r = Z_OK;
1489 }
1490 #else
1491 inflate_trees_free(*td, z);
1492 z->msg = "incomplete literal/length tree";
1493 r = Z_DATA_ERROR;
1494 }
1495 inflate_trees_free(*tl, z);
1496 return r;
1497 #endif
1498 }
1499
1500 /* done */
1501 return Z_OK;
1502 }
1503
1504
1505 /* build fixed tables only once--keep them here */
1506 local int fixed_lock = 0;
1507 local int fixed_built = 0;
1508 #define FIXEDH 530 /* number of hufts used by fixed tables */
1509 local uInt fixed_left = FIXEDH;
1510 local inflate_huft fixed_mem[FIXEDH];
1511 local uInt fixed_bl;
1512 local uInt fixed_bd;
1513 local inflate_huft *fixed_tl;
1514 local inflate_huft *fixed_td;
1515
1516
1517 local voidpf falloc(q, n, s)
1518 voidpf q; /* opaque pointer (not used) */
1519 uInt n; /* number of items */
1520 uInt s; /* size of item */
1521 {
1522 Assert(s == sizeof(inflate_huft) && n <= fixed_left,
1523 "inflate_trees falloc overflow");
1524 if (q) s++; /* to make some compilers happy */
1525 fixed_left -= n;
1526 return (voidpf)(fixed_mem + fixed_left);
1527 }
1528
1529
1530 local void ffree(q, p, n)
1531 voidpf q;
1532 voidpf p;
1533 uInt n;
1534 {
1535 Assert(0, "inflate_trees ffree called!");
1536 if (q) q = p; /* to make some compilers happy */
1537 }
1538
1539
1540 local int inflate_trees_fixed(bl, bd, tl, td)
1541 uIntf *bl; /* literal desired/actual bit depth */
1542 uIntf *bd; /* distance desired/actual bit depth */
1543 inflate_huft * FAR *tl; /* literal/length tree result */
1544 inflate_huft * FAR *td; /* distance tree result */
1545 {
1546 /* build fixed tables if not built already--lock out other instances */
1547 while (++fixed_lock > 1)
1548 fixed_lock--;
1549 if (!fixed_built)
1550 {
1551 int k; /* temporary variable */
1552 unsigned c[288]; /* length list for huft_build */
1553 z_stream z; /* for falloc function */
1554
1555 /* set up fake z_stream for memory routines */
1556 z.zalloc = falloc;
1557 z.zfree = ffree;
1558 z.opaque = Z_NULL;
1559
1560 /* literal table */
1561 for (k = 0; k < 144; k++)
1562 c[k] = 8;
1563 for (; k < 256; k++)
1564 c[k] = 9;
1565 for (; k < 280; k++)
1566 c[k] = 7;
1567 for (; k < 288; k++)
1568 c[k] = 8;
1569 fixed_bl = 7;
1570 huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl, &z);
1571
1572 /* distance table */
1573 for (k = 0; k < 30; k++)
1574 c[k] = 5;
1575 fixed_bd = 5;
1576 huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd, &z);
1577
1578 /* done */
1579 fixed_built = 1;
1580 }
1581 fixed_lock--;
1582 *bl = fixed_bl;
1583 *bd = fixed_bd;
1584 *tl = fixed_tl;
1585 *td = fixed_td;
1586 return Z_OK;
1587 }
1588
1589
1590 local int inflate_trees_free(t, z)
1591 inflate_huft *t; /* table to free */
1592 z_stream *z; /* for zfree function */
1593 /* Free the malloc'ed tables built by huft_build(), which makes a linked
1594 list of the tables it made, with the links in a dummy first entry of
1595 each table. */
1596 {
1597 register inflate_huft *p, *q;
1598
1599 /* Go through linked list, freeing from the malloced (t[-1]) address. */
1600 p = t;
1601 while (p != Z_NULL)
1602 {
1603 q = (--p)->next;
1604 ZFREE(z, p, p->word.Nalloc * sizeof(inflate_huft));
1605 p = q;
1606 }
1607 return Z_OK;
1608 }
1609
1610 /*+++++*/
1611 /* infcodes.c -- process literals and length/distance pairs
1612 * Copyright (C) 1995 Mark Adler
1613 * For conditions of distribution and use, see copyright notice in zlib.h
1614 */
1615
1616 /* simplify the use of the inflate_huft type with some defines */
1617 #define base more.Base
1618 #define next more.Next
1619 #define exop word.what.Exop
1620 #define bits word.what.Bits
1621
1622 /* inflate codes private state */
1623 struct inflate_codes_state {
1624
1625 /* mode */
1626 enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
1627 START, /* x: set up for LEN */
1628 LEN, /* i: get length/literal/eob next */
1629 LENEXT, /* i: getting length extra (have base) */
1630 DIST, /* i: get distance next */
1631 DISTEXT, /* i: getting distance extra */
1632 COPY, /* o: copying bytes in window, waiting for space */
1633 LIT, /* o: got literal, waiting for output space */
1634 WASH, /* o: got eob, possibly still output waiting */
1635 END, /* x: got eob and all data flushed */
1636 BADCODE} /* x: got error */
1637 mode; /* current inflate_codes mode */
1638
1639 /* mode dependent information */
1640 uInt len;
1641 union {
1642 struct {
1643 inflate_huft *tree; /* pointer into tree */
1644 uInt need; /* bits needed */
1645 } code; /* if LEN or DIST, where in tree */
1646 uInt lit; /* if LIT, literal */
1647 struct {
1648 uInt get; /* bits to get for extra */
1649 uInt dist; /* distance back to copy from */
1650 } copy; /* if EXT or COPY, where and how much */
1651 } sub; /* submode */
1652
1653 /* mode independent information */
1654 Byte lbits; /* ltree bits decoded per branch */
1655 Byte dbits; /* dtree bits decoder per branch */
1656 inflate_huft *ltree; /* literal/length/eob tree */
1657 inflate_huft *dtree; /* distance tree */
1658
1659 };
1660
1661
1662 local inflate_codes_statef *inflate_codes_new(bl, bd, tl, td, z)
1663 uInt bl, bd;
1664 inflate_huft *tl, *td;
1665 z_stream *z;
1666 {
1667 inflate_codes_statef *c;
1668
1669 if ((c = (inflate_codes_statef *)
1670 ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL)
1671 {
1672 c->mode = START;
1673 c->lbits = (Byte)bl;
1674 c->dbits = (Byte)bd;
1675 c->ltree = tl;
1676 c->dtree = td;
1677 Tracev((stderr, "inflate: codes new\n"));
1678 }
1679 return c;
1680 }
1681
1682
1683 local int inflate_codes(s, z, r)
1684 inflate_blocks_statef *s;
1685 z_stream *z;
1686 int r;
1687 {
1688 uInt j; /* temporary storage */
1689 inflate_huft *t; /* temporary pointer */
1690 uInt e; /* extra bits or operation */
1691 uLong b; /* bit buffer */
1692 uInt k; /* bits in bit buffer */
1693 Bytef *p; /* input data pointer */
1694 uInt n; /* bytes available there */
1695 Bytef *q; /* output window write pointer */
1696 uInt m; /* bytes to end of window or read pointer */
1697 Bytef *f; /* pointer to copy strings from */
1698 inflate_codes_statef *c = s->sub.decode.codes; /* codes state */
1699
1700 /* copy input/output information to locals (UPDATE macro restores) */
1701 LOAD
1702
1703 /* process input and output based on current state */
1704 while (1) switch (c->mode)
1705 { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
1706 case START: /* x: set up for LEN */
1707 #ifndef SLOW
1708 if (m >= 258 && n >= 10)
1709 {
1710 UPDATE
1711 r = inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z);
1712 LOAD
1713 if (r != Z_OK)
1714 {
1715 c->mode = r == Z_STREAM_END ? WASH : BADCODE;
1716 break;
1717 }
1718 }
1719 #endif /* !SLOW */
1720 c->sub.code.need = c->lbits;
1721 c->sub.code.tree = c->ltree;
1722 c->mode = LEN;
1723 case LEN: /* i: get length/literal/eob next */
1724 j = c->sub.code.need;
1725 NEEDBITS(j)
1726 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
1727 DUMPBITS(t->bits)
1728 e = (uInt)(t->exop);
1729 if (e == 0) /* literal */
1730 {
1731 c->sub.lit = t->base;
1732 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
1733 "inflate: literal '%c'\n" :
1734 "inflate: literal 0x%02x\n", t->base));
1735 c->mode = LIT;
1736 break;
1737 }
1738 if (e & 16) /* length */
1739 {
1740 c->sub.copy.get = e & 15;
1741 c->len = t->base;
1742 c->mode = LENEXT;
1743 break;
1744 }
1745 if ((e & 64) == 0) /* next table */
1746 {
1747 c->sub.code.need = e;
1748 c->sub.code.tree = t->next;
1749 break;
1750 }
1751 if (e & 32) /* end of block */
1752 {
1753 Tracevv((stderr, "inflate: end of block\n"));
1754 c->mode = WASH;
1755 break;
1756 }
1757 c->mode = BADCODE; /* invalid code */
1758 z->msg = "invalid literal/length code";
1759 r = Z_DATA_ERROR;
1760 LEAVE
1761 case LENEXT: /* i: getting length extra (have base) */
1762 j = c->sub.copy.get;
1763 NEEDBITS(j)
1764 c->len += (uInt)b & inflate_mask[j];
1765 DUMPBITS(j)
1766 c->sub.code.need = c->dbits;
1767 c->sub.code.tree = c->dtree;
1768 Tracevv((stderr, "inflate: length %u\n", c->len));
1769 c->mode = DIST;
1770 case DIST: /* i: get distance next */
1771 j = c->sub.code.need;
1772 NEEDBITS(j)
1773 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
1774 DUMPBITS(t->bits)
1775 e = (uInt)(t->exop);
1776 if (e & 16) /* distance */
1777 {
1778 c->sub.copy.get = e & 15;
1779 c->sub.copy.dist = t->base;
1780 c->mode = DISTEXT;
1781 break;
1782 }
1783 if ((e & 64) == 0) /* next table */
1784 {
1785 c->sub.code.need = e;
1786 c->sub.code.tree = t->next;
1787 break;
1788 }
1789 c->mode = BADCODE; /* invalid code */
1790 z->msg = "invalid distance code";
1791 r = Z_DATA_ERROR;
1792 LEAVE
1793 case DISTEXT: /* i: getting distance extra */
1794 j = c->sub.copy.get;
1795 NEEDBITS(j)
1796 c->sub.copy.dist += (uInt)b & inflate_mask[j];
1797 DUMPBITS(j)
1798 Tracevv((stderr, "inflate: distance %u\n", c->sub.copy.dist));
1799 c->mode = COPY;
1800 case COPY: /* o: copying bytes in window, waiting for space */
1801 #ifndef __TURBOC__ /* Turbo C bug for following expression */
1802 f = (uInt)(q - s->window) < c->sub.copy.dist ?
1803 s->end - (c->sub.copy.dist - (q - s->window)) :
1804 q - c->sub.copy.dist;
1805 #else
1806 f = q - c->sub.copy.dist;
1807 if ((uInt)(q - s->window) < c->sub.copy.dist)
1808 f = s->end - (c->sub.copy.dist - (q - s->window));
1809 #endif
1810 while (c->len)
1811 {
1812 NEEDOUT
1813 OUTBYTE(*f++)
1814 if (f == s->end)
1815 f = s->window;
1816 c->len--;
1817 }
1818 c->mode = START;
1819 break;
1820 case LIT: /* o: got literal, waiting for output space */
1821 NEEDOUT
1822 OUTBYTE(c->sub.lit)
1823 c->mode = START;
1824 break;
1825 case WASH: /* o: got eob, possibly more output */
1826 FLUSH
1827 if (s->read != s->write)
1828 LEAVE
1829 c->mode = END;
1830 case END:
1831 r = Z_STREAM_END;
1832 LEAVE
1833 case BADCODE: /* x: got error */
1834 r = Z_DATA_ERROR;
1835 LEAVE
1836 default:
1837 r = Z_STREAM_ERROR;
1838 LEAVE
1839 }
1840 }
1841
1842
1843 local void inflate_codes_free(c, z)
1844 inflate_codes_statef *c;
1845 z_stream *z;
1846 {
1847 ZFREE(z, c, sizeof(struct inflate_codes_state));
1848 Tracev((stderr, "inflate: codes free\n"));
1849 }
1850
1851 /*+++++*/
1852 /* inflate_util.c -- data and routines common to blocks and codes
1853 * Copyright (C) 1995 Mark Adler
1854 * For conditions of distribution and use, see copyright notice in zlib.h
1855 */
1856
1857 /* copy as much as possible from the sliding window to the output area */
1858 local int inflate_flush(s, z, r)
1859 inflate_blocks_statef *s;
1860 z_stream *z;
1861 int r;
1862 {
1863 uInt n;
1864 Bytef *p, *q;
1865
1866 /* local copies of source and destination pointers */
1867 p = z->next_out;
1868 q = s->read;
1869
1870 /* compute number of bytes to copy as far as end of window */
1871 n = (uInt)((q <= s->write ? s->write : s->end) - q);
1872 if (n > z->avail_out) n = z->avail_out;
1873 if (n && r == Z_BUF_ERROR) r = Z_OK;
1874
1875 /* update counters */
1876 z->avail_out -= n;
1877 z->total_out += n;
1878
1879 /* update check information */
1880 if (s->checkfn != Z_NULL)
1881 s->check = (*s->checkfn)(s->check, q, n);
1882
1883 /* copy as far as end of window */
1884 zmemcpy(p, q, n);
1885 p += n;
1886 q += n;
1887
1888 /* see if more to copy at beginning of window */
1889 if (q == s->end)
1890 {
1891 /* wrap pointers */
1892 q = s->window;
1893 if (s->write == s->end)
1894 s->write = s->window;
1895
1896 /* compute bytes to copy */
1897 n = (uInt)(s->write - q);
1898 if (n > z->avail_out) n = z->avail_out;
1899 if (n && r == Z_BUF_ERROR) r = Z_OK;
1900
1901 /* update counters */
1902 z->avail_out -= n;
1903 z->total_out += n;
1904
1905 /* update check information */
1906 if (s->checkfn != Z_NULL)
1907 s->check = (*s->checkfn)(s->check, q, n);
1908
1909 /* copy */
1910 zmemcpy(p, q, n);
1911 p += n;
1912 q += n;
1913 }
1914
1915 /* update pointers */
1916 z->next_out = p;
1917 s->read = q;
1918
1919 /* done */
1920 return r;
1921 }
1922
1923
1924 /*+++++*/
1925 /* inffast.c -- process literals and length/distance pairs fast
1926 * Copyright (C) 1995 Mark Adler
1927 * For conditions of distribution and use, see copyright notice in zlib.h
1928 */
1929
1930 /* simplify the use of the inflate_huft type with some defines */
1931 #define base more.Base
1932 #define next more.Next
1933 #define exop word.what.Exop
1934 #define bits word.what.Bits
1935
1936 /* macros for bit input with no checking and for returning unused bytes */
1937 #define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}}
1938 #define UNGRAB {n+=(c=k>>3);p-=c;k&=7;}
1939
1940 /* Called with number of bytes left to write in window at least 258
1941 (the maximum string length) and number of input bytes available
1942 at least ten. The ten bytes are six bytes for the longest length/
1943 distance pair plus four bytes for overloading the bit buffer. */
1944
1945 local int inflate_fast(bl, bd, tl, td, s, z)
1946 uInt bl, bd;
1947 inflate_huft *tl, *td;
1948 inflate_blocks_statef *s;
1949 z_stream *z;
1950 {
1951 inflate_huft *t; /* temporary pointer */
1952 uInt e; /* extra bits or operation */
1953 uLong b; /* bit buffer */
1954 uInt k; /* bits in bit buffer */
1955 Bytef *p; /* input data pointer */
1956 uInt n; /* bytes available there */
1957 Bytef *q; /* output window write pointer */
1958 uInt m; /* bytes to end of window or read pointer */
1959 uInt ml; /* mask for literal/length tree */
1960 uInt md; /* mask for distance tree */
1961 uInt c; /* bytes to copy */
1962 uInt d; /* distance back to copy from */
1963 Bytef *r; /* copy source pointer */
1964
1965 /* load input, output, bit values */
1966 LOAD
1967
1968 /* initialize masks */
1969 ml = inflate_mask[bl];
1970 md = inflate_mask[bd];
1971
1972 /* do until not enough input or output space for fast loop */
1973 do { /* assume called with m >= 258 && n >= 10 */
1974 /* get literal/length code */
1975 GRABBITS(20) /* max bits for literal/length code */
1976 if ((e = (t = tl + ((uInt)b & ml))->exop) == 0)
1977 {
1978 DUMPBITS(t->bits)
1979 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
1980 "inflate: * literal '%c'\n" :
1981 "inflate: * literal 0x%02x\n", t->base));
1982 *q++ = (Byte)t->base;
1983 m--;
1984 continue;
1985 }
1986 do {
1987 DUMPBITS(t->bits)
1988 if (e & 16)
1989 {
1990 /* get extra bits for length */
1991 e &= 15;
1992 c = t->base + ((uInt)b & inflate_mask[e]);
1993 DUMPBITS(e)
1994 Tracevv((stderr, "inflate: * length %u\n", c));
1995
1996 /* decode distance base of block to copy */
1997 GRABBITS(15); /* max bits for distance code */
1998 e = (t = td + ((uInt)b & md))->exop;
1999 do {
2000 DUMPBITS(t->bits)
2001 if (e & 16)
2002 {
2003 /* get extra bits to add to distance base */
2004 e &= 15;
2005 GRABBITS(e) /* get extra bits (up to 13) */
2006 d = t->base + ((uInt)b & inflate_mask[e]);
2007 DUMPBITS(e)
2008 Tracevv((stderr, "inflate: * distance %u\n", d));
2009
2010 /* do the copy */
2011 m -= c;
2012 if ((uInt)(q - s->window) >= d) /* offset before dest */
2013 { /* just copy */
2014 r = q - d;
2015 *q++ = *r++; c--; /* minimum count is three, */
2016 *q++ = *r++; c--; /* so unroll loop a little */
2017 }
2018 else /* else offset after destination */
2019 {
2020 e = d - (q - s->window); /* bytes from offset to end */
2021 r = s->end - e; /* pointer to offset */
2022 if (c > e) /* if source crosses, */
2023 {
2024 c -= e; /* copy to end of window */
2025 do {
2026 *q++ = *r++;
2027 } while (--e);
2028 r = s->window; /* copy rest from start of window */
2029 }
2030 }
2031 do { /* copy all or what's left */
2032 *q++ = *r++;
2033 } while (--c);
2034 break;
2035 }
2036 else if ((e & 64) == 0)
2037 e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop;
2038 else
2039 {
2040 z->msg = "invalid distance code";
2041 UNGRAB
2042 UPDATE
2043 return Z_DATA_ERROR;
2044 }
2045 } while (1);
2046 break;
2047 }
2048 if ((e & 64) == 0)
2049 {
2050 if ((e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop) == 0)
2051 {
2052 DUMPBITS(t->bits)
2053 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
2054 "inflate: * literal '%c'\n" :
2055 "inflate: * literal 0x%02x\n", t->base));
2056 *q++ = (Byte)t->base;
2057 m--;
2058 break;
2059 }
2060 }
2061 else if (e & 32)
2062 {
2063 Tracevv((stderr, "inflate: * end of block\n"));
2064 UNGRAB
2065 UPDATE
2066 return Z_STREAM_END;
2067 }
2068 else
2069 {
2070 z->msg = "invalid literal/length code";
2071 UNGRAB
2072 UPDATE
2073 return Z_DATA_ERROR;
2074 }
2075 } while (1);
2076 } while (m >= 258 && n >= 10);
2077
2078 /* not enough input or output--restore pointers and return */
2079 UNGRAB
2080 UPDATE
2081 return Z_OK;
2082 }
2083
2084
2085 /*+++++*/
2086 /* zutil.c -- target dependent utility functions for the compression library
2087 * Copyright (C) 1995 Jean-loup Gailly.
2088 * For conditions of distribution and use, see copyright notice in zlib.h
2089 */
2090
2091 /* From: zutil.c,v 1.8 1995/05/03 17:27:12 jloup Exp */
2092
2093 char *zlib_version = ZLIB_VERSION;
2094
2095 char *z_errmsg[] = {
2096 "stream end", /* Z_STREAM_END 1 */
2097 "", /* Z_OK 0 */
2098 "file error", /* Z_ERRNO (-1) */
2099 "stream error", /* Z_STREAM_ERROR (-2) */
2100 "data error", /* Z_DATA_ERROR (-3) */
2101 "insufficient memory", /* Z_MEM_ERROR (-4) */
2102 "buffer error", /* Z_BUF_ERROR (-5) */
2103 ""};
2104
2105
2106 /*+++++*/
2107 /* adler32.c -- compute the Adler-32 checksum of a data stream
2108 * Copyright (C) 1995 Mark Adler
2109 * For conditions of distribution and use, see copyright notice in zlib.h
2110 */
2111
2112 /* From: adler32.c,v 1.6 1995/05/03 17:27:08 jloup Exp */
2113
2114 #define BASE 65521L /* largest prime smaller than 65536 */
2115 #define NMAX 5552
2116 /* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
2117
2118 #define DO1(buf) {s1 += *buf++; s2 += s1;}
2119 #define DO2(buf) DO1(buf); DO1(buf);
2120 #define DO4(buf) DO2(buf); DO2(buf);
2121 #define DO8(buf) DO4(buf); DO4(buf);
2122 #define DO16(buf) DO8(buf); DO8(buf);
2123
2124 /* ========================================================================= */
2125 uLong adler32(adler, buf, len)
2126 uLong adler;
2127 Bytef *buf;
2128 uInt len;
2129 {
2130 unsigned long s1 = adler & 0xffff;
2131 unsigned long s2 = (adler >> 16) & 0xffff;
2132 int k;
2133
2134 if (buf == Z_NULL) return 1L;
2135
2136 while (len > 0) {
2137 k = len < NMAX ? len : NMAX;
2138 len -= k;
2139 while (k >= 16) {
2140 DO16(buf);
2141 k -= 16;
2142 }
2143 if (k != 0) do {
2144 DO1(buf);
2145 } while (--k);
2146 s1 %= BASE;
2147 s2 %= BASE;
2148 }
2149 return (s2 << 16) | s1;
2150 }
2151