2 * This file is derived from various .h and .c files from the zlib-0.95
3 * distribution by Jean-loup Gailly and Mark Adler, with some additions
4 * by Paul Mackerras to aid in implementing Deflate compression and
5 * decompression for PPP packets. See zlib.h for conditions of
6 * distribution and use.
8 * Changes that have been made include:
9 * - changed functions not used outside this file to "local"
10 * - added minCompression parameter to deflateInit2
11 * - added Z_PACKET_FLUSH (see zlib.h for details)
12 * - added inflateIncomp
17 /* zutil.h -- internal interface and configuration of the compression library
18 * Copyright (C) 1995 Jean-loup Gailly.
19 * For conditions of distribution and use, see copyright notice in zlib.h
22 /* WARNING: this file should *not* be used by applications. It is
23 part of the implementation of the compression library and is
24 subject to change. Applications should only use zlib.h.
27 /* From: zutil.h,v 1.9 1995/05/03 17:27:12 jloup Exp */
36 /* compile with -Dlocal if your debugger can't find static symbols */
40 typedef unsigned char uch;
42 typedef unsigned short ush;
44 typedef unsigned long ulg;
46 extern char *z_errmsg[]; /* indexed by 1-zlib_error */
48 #define ERR_RETURN(strm,err) return (strm->msg=z_errmsg[1-err], err)
49 /* To be used only when the state is known to be valid */
52 #define NULL ((void *) 0)
55 /* common constants */
60 # define DEF_WBITS MAX_WBITS
62 /* default windowBits for decompression. MAX_WBITS is for compression only */
64 #if MAX_MEM_LEVEL >= 8
65 # define DEF_MEM_LEVEL 8
67 # define DEF_MEM_LEVEL MAX_MEM_LEVEL
69 /* default memLevel */
71 #define STORED_BLOCK 0
72 #define STATIC_TREES 1
74 /* The three kinds of block type */
78 /* The minimum and maximum match lengths */
82 #include <linux/string.h>
83 #define zmemcpy memcpy
84 #define zmemzero(dest, len) memset(dest, 0, len)
86 /* Diagnostic functions */
92 # define Assert(cond,msg) {if(!(cond)) z_error(msg);}
93 # define Trace(x) fprintf x
94 # define Tracev(x) {if (verbose) fprintf x ;}
95 # define Tracevv(x) {if (verbose>1) fprintf x ;}
96 # define Tracec(c,x) {if (verbose && (c)) fprintf x ;}
97 # define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;}
99 # define Assert(cond,msg)
104 # define Tracecv(c,x)
108 typedef uLong (*check_func) OF((uLong check, Bytef *buf, uInt len));
110 /* voidpf zcalloc OF((voidpf opaque, unsigned items, unsigned size)); */
111 /* void zcfree OF((voidpf opaque, voidpf ptr)); */
113 #define ZALLOC(strm, items, size) \
114 (*((strm)->zalloc))((strm)->opaque, (items), (size))
115 #define ZFREE(strm, addr, size) \
116 (*((strm)->zfree))((strm)->opaque, (voidpf)(addr), (size))
117 #define TRY_FREE(s, p, n) {if (p) ZFREE(s, p, n);}
119 /* deflate.h -- internal compression state
120 * Copyright (C) 1995 Jean-loup Gailly
121 * For conditions of distribution and use, see copyright notice in zlib.h
124 /* WARNING: this file should *not* be used by applications. It is
125 part of the implementation of the compression library and is
126 subject to change. Applications should only use zlib.h.
130 /* infblock.h -- header to use infblock.c
131 * Copyright (C) 1995 Mark Adler
132 * For conditions of distribution and use, see copyright notice in zlib.h
135 /* WARNING: this file should *not* be used by applications. It is
136 part of the implementation of the compression library and is
137 subject to change. Applications should only use zlib.h.
140 struct inflate_blocks_state;
141 typedef struct inflate_blocks_state FAR inflate_blocks_statef;
143 local inflate_blocks_statef * inflate_blocks_new OF((
145 check_func c, /* check function */
146 uInt w)); /* window size */
148 local int inflate_blocks OF((
149 inflate_blocks_statef *,
151 int)); /* initial return code */
153 local void inflate_blocks_reset OF((
154 inflate_blocks_statef *,
156 uLongf *)); /* check value on output */
158 local int inflate_blocks_free OF((
159 inflate_blocks_statef *,
161 uLongf *)); /* check value on output */
163 local int inflate_addhistory OF((
164 inflate_blocks_statef *,
167 local int inflate_packet_flush OF((
168 inflate_blocks_statef *));
171 /* inftrees.h -- header to use inftrees.c
172 * Copyright (C) 1995 Mark Adler
173 * For conditions of distribution and use, see copyright notice in zlib.h
176 /* WARNING: this file should *not* be used by applications. It is
177 part of the implementation of the compression library and is
178 subject to change. Applications should only use zlib.h.
181 /* Huffman code lookup table entry--this entry is four bytes for machines
182 that have 16-bit pointers (e.g. PC's in the small or medium model). */
184 typedef struct inflate_huft_s FAR inflate_huft;
186 struct inflate_huft_s {
189 Byte Exop; /* number of extra bits or operation */
190 Byte Bits; /* number of bits in this code or subcode */
192 uInt Nalloc; /* number of these allocated here */
193 Bytef *pad; /* pad structure to a power of 2 (4 bytes for */
194 } word; /* 16-bit, 8 bytes for 32-bit machines) */
196 uInt Base; /* literal, length base, or distance base */
197 inflate_huft *Next; /* pointer to next level of table */
202 local uInt inflate_hufts;
205 local int inflate_trees_bits OF((
206 uIntf *, /* 19 code lengths */
207 uIntf *, /* bits tree desired/actual depth */
208 inflate_huft * FAR *, /* bits tree result */
209 z_stream *)); /* for zalloc, zfree functions */
211 local int inflate_trees_dynamic OF((
212 uInt, /* number of literal/length codes */
213 uInt, /* number of distance codes */
214 uIntf *, /* that many (total) code lengths */
215 uIntf *, /* literal desired/actual bit depth */
216 uIntf *, /* distance desired/actual bit depth */
217 inflate_huft * FAR *, /* literal/length tree result */
218 inflate_huft * FAR *, /* distance tree result */
219 z_stream *)); /* for zalloc, zfree functions */
221 local int inflate_trees_fixed OF((
222 uIntf *, /* literal desired/actual bit depth */
223 uIntf *, /* distance desired/actual bit depth */
224 inflate_huft * FAR *, /* literal/length tree result */
225 inflate_huft * FAR *)); /* distance tree result */
227 local int inflate_trees_free OF((
228 inflate_huft *, /* tables to free */
229 z_stream *)); /* for zfree function */
233 /* infcodes.h -- header to use infcodes.c
234 * Copyright (C) 1995 Mark Adler
235 * For conditions of distribution and use, see copyright notice in zlib.h
238 /* WARNING: this file should *not* be used by applications. It is
239 part of the implementation of the compression library and is
240 subject to change. Applications should only use zlib.h.
243 struct inflate_codes_state;
244 typedef struct inflate_codes_state FAR inflate_codes_statef;
246 local inflate_codes_statef *inflate_codes_new OF((
248 inflate_huft *, inflate_huft *,
251 local int inflate_codes OF((
252 inflate_blocks_statef *,
256 local void inflate_codes_free OF((
257 inflate_codes_statef *,
262 /* inflate.c -- zlib interface to inflate modules
263 * Copyright (C) 1995 Mark Adler
264 * For conditions of distribution and use, see copyright notice in zlib.h
267 /* inflate private state */
268 struct internal_state {
272 METHOD, /* waiting for method byte */
273 FLAG, /* waiting for flag byte */
274 BLOCKS, /* decompressing blocks */
275 CHECK4, /* four check bytes to go */
276 CHECK3, /* three check bytes to go */
277 CHECK2, /* two check bytes to go */
278 CHECK1, /* one check byte to go */
279 DONE, /* finished check, done */
280 BAD} /* got an error--stay here */
281 mode; /* current inflate mode */
283 /* mode dependent information */
285 uInt method; /* if FLAGS, method byte */
287 uLong was; /* computed check value */
288 uLong need; /* stream check value */
289 } check; /* if CHECK, check values to compare */
290 uInt marker; /* if BAD, inflateSync's marker bytes count */
293 /* mode independent information */
294 int nowrap; /* flag for no wrapper */
295 uInt wbits; /* log2(window size) (8..15, defaults to 15) */
296 inflate_blocks_statef
297 *blocks; /* current inflate_blocks state */
307 if (z == Z_NULL || z->state == Z_NULL)
308 return Z_STREAM_ERROR;
309 z->total_in = z->total_out = 0;
311 z->state->mode = z->state->nowrap ? BLOCKS : METHOD;
312 inflate_blocks_reset(z->state->blocks, z, &c);
313 Trace((stderr, "inflate: reset\n"));
323 if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL)
324 return Z_STREAM_ERROR;
325 if (z->state->blocks != Z_NULL)
326 inflate_blocks_free(z->state->blocks, z, &c);
327 ZFREE(z, z->state, sizeof(struct internal_state));
329 Trace((stderr, "inflate: end\n"));
334 int inflateInit2(z, w)
338 /* initialize state */
340 return Z_STREAM_ERROR;
341 /* if (z->zalloc == Z_NULL) z->zalloc = zcalloc; */
342 /* if (z->zfree == Z_NULL) z->zfree = zcfree; */
343 if ((z->state = (struct internal_state FAR *)
344 ZALLOC(z,1,sizeof(struct internal_state))) == Z_NULL)
346 z->state->blocks = Z_NULL;
348 /* handle undocumented nowrap option (no zlib header or check) */
349 z->state->nowrap = 0;
353 z->state->nowrap = 1;
356 /* set window size */
360 return Z_STREAM_ERROR;
362 z->state->wbits = (uInt)w;
364 /* create inflate_blocks state */
365 if ((z->state->blocks =
366 inflate_blocks_new(z, z->state->nowrap ? Z_NULL : adler32, 1 << w))
372 Trace((stderr, "inflate: allocated\n"));
383 return inflateInit2(z, DEF_WBITS);
387 #define NEEDBYTE {if(z->avail_in==0)goto empty;r=Z_OK;}
388 #define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++)
397 if (z == Z_NULL || z->next_in == Z_NULL)
398 return Z_STREAM_ERROR;
400 while (1) switch (z->state->mode)
404 if (((z->state->sub.method = NEXTBYTE) & 0xf) != DEFLATED)
406 z->state->mode = BAD;
407 z->msg = "unknown compression method";
408 z->state->sub.marker = 5; /* can't try inflateSync */
411 if ((z->state->sub.method >> 4) + 8 > z->state->wbits)
413 z->state->mode = BAD;
414 z->msg = "invalid window size";
415 z->state->sub.marker = 5; /* can't try inflateSync */
418 z->state->mode = FLAG;
421 if ((b = NEXTBYTE) & 0x20)
423 z->state->mode = BAD;
424 z->msg = "invalid reserved bit";
425 z->state->sub.marker = 5; /* can't try inflateSync */
428 if (((z->state->sub.method << 8) + b) % 31)
430 z->state->mode = BAD;
431 z->msg = "incorrect header check";
432 z->state->sub.marker = 5; /* can't try inflateSync */
435 Trace((stderr, "inflate: zlib header ok\n"));
436 z->state->mode = BLOCKS;
438 r = inflate_blocks(z->state->blocks, z, r);
439 if (f == Z_PACKET_FLUSH && z->avail_in == 0 && z->avail_out != 0)
440 r = inflate_packet_flush(z->state->blocks);
441 if (r == Z_DATA_ERROR)
443 z->state->mode = BAD;
444 z->state->sub.marker = 0; /* can try inflateSync */
447 if (r != Z_STREAM_END)
450 inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was);
451 if (z->state->nowrap)
453 z->state->mode = DONE;
456 z->state->mode = CHECK4;
459 z->state->sub.check.need = (uLong)NEXTBYTE << 24;
460 z->state->mode = CHECK3;
463 z->state->sub.check.need += (uLong)NEXTBYTE << 16;
464 z->state->mode = CHECK2;
467 z->state->sub.check.need += (uLong)NEXTBYTE << 8;
468 z->state->mode = CHECK1;
471 z->state->sub.check.need += (uLong)NEXTBYTE;
473 if (z->state->sub.check.was != z->state->sub.check.need)
475 z->state->mode = BAD;
476 z->msg = "incorrect data check";
477 z->state->sub.marker = 5; /* can't try inflateSync */
480 Trace((stderr, "inflate: zlib check ok\n"));
481 z->state->mode = DONE;
487 return Z_STREAM_ERROR;
491 if (f != Z_PACKET_FLUSH)
493 z->state->mode = BAD;
494 z->state->sub.marker = 0; /* can try inflateSync */
499 * This subroutine adds the data at next_in/avail_in to the output history
500 * without performing any output. The output buffer must be "caught up";
501 * i.e. no pending output (hence s->read equals s->write), and the state must
502 * be BLOCKS (i.e. we should be willing to see the start of a series of
503 * BLOCKS). On exit, the output will also be caught up, and the checksum
504 * will have been updated if need be.
510 if (z->state->mode != BLOCKS)
512 return inflate_addhistory(z->state->blocks, z);
519 uInt n; /* number of bytes to look at */
520 Bytef *p; /* pointer to bytes */
521 uInt m; /* number of marker bytes found in a row */
522 uLong r, w; /* temporaries to save total_in and total_out */
525 if (z == Z_NULL || z->state == Z_NULL)
526 return Z_STREAM_ERROR;
527 if (z->state->mode != BAD)
529 z->state->mode = BAD;
530 z->state->sub.marker = 0;
532 if ((n = z->avail_in) == 0)
535 m = z->state->sub.marker;
540 if (*p == (Byte)(m < 2 ? 0 : 0xff))
550 z->total_in += p - z->next_in;
553 z->state->sub.marker = m;
555 /* return no joy or set up to restart on a new block */
558 r = z->total_in; w = z->total_out;
560 z->total_in = r; z->total_out = w;
561 z->state->mode = BLOCKS;
569 /* infutil.h -- types and macros common to blocks and codes
570 * Copyright (C) 1995 Mark Adler
571 * For conditions of distribution and use, see copyright notice in zlib.h
574 /* WARNING: this file should *not* be used by applications. It is
575 part of the implementation of the compression library and is
576 subject to change. Applications should only use zlib.h.
579 /* inflate blocks semi-private state */
580 struct inflate_blocks_state {
584 TYPE, /* get type bits (3, including end bit) */
585 LENS, /* get lengths for stored */
586 STORED, /* processing stored block */
587 TABLE, /* get table lengths */
588 BTREE, /* get bit lengths tree for a dynamic block */
589 DTREE, /* get length, distance trees for a dynamic block */
590 CODES, /* processing fixed or dynamic block */
591 DRY, /* output remaining window bytes */
592 DONEB, /* finished last block, done */
593 BADB} /* got a data error--stuck here */
594 mode; /* current inflate_block mode */
596 /* mode dependent information */
598 uInt left; /* if STORED, bytes left to copy */
600 uInt table; /* table lengths (14 bits) */
601 uInt index; /* index into blens (or border) */
602 uIntf *blens; /* bit lengths of codes */
603 uInt bb; /* bit length tree depth */
604 inflate_huft *tb; /* bit length decoding tree */
605 int nblens; /* # elements allocated at blens */
606 } trees; /* if DTREE, decoding info for trees */
608 inflate_huft *tl, *td; /* trees to free */
611 } decode; /* if CODES, current state */
613 uInt last; /* true if this block is the last block */
615 /* mode independent information */
616 uInt bitk; /* bits in bit buffer */
617 uLong bitb; /* bit buffer */
618 Bytef *window; /* sliding window */
619 Bytef *end; /* one byte after sliding window */
620 Bytef *read; /* window read pointer */
621 Bytef *write; /* window write pointer */
622 check_func checkfn; /* check function */
623 uLong check; /* check on output */
628 /* defines for inflate input/output */
629 /* update pointers and return */
630 #define UPDBITS {s->bitb=b;s->bitk=k;}
631 #define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;}
632 #define UPDOUT {s->write=q;}
633 #define UPDATE {UPDBITS UPDIN UPDOUT}
634 #define LEAVE {UPDATE return inflate_flush(s,z,r);}
635 /* get bytes and bits */
636 #define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;}
637 #define NEEDBYTE {if(n)r=Z_OK;else LEAVE}
638 #define NEXTBYTE (n--,*p++)
639 #define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}}
640 #define DUMPBITS(j) {b>>=(j);k-=(j);}
642 #define WAVAIL (q<s->read?s->read-q-1:s->end-q)
643 #define LOADOUT {q=s->write;m=WAVAIL;}
644 #define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=WAVAIL;}}
645 #define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT}
646 #define NEEDOUT {if(m==0){WRAP if(m==0){FLUSH WRAP if(m==0) LEAVE}}r=Z_OK;}
647 #define OUTBYTE(a) {*q++=(Byte)(a);m--;}
648 /* load local pointers */
649 #define LOAD {LOADIN LOADOUT}
651 /* And'ing with mask[n] masks the lower n bits */
652 local uInt inflate_mask[] = {
654 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
655 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
658 /* copy as much as possible from the sliding window to the output area */
659 local int inflate_flush OF((
660 inflate_blocks_statef *,
665 /* inffast.h -- header to use inffast.c
666 * Copyright (C) 1995 Mark Adler
667 * For conditions of distribution and use, see copyright notice in zlib.h
670 /* WARNING: this file should *not* be used by applications. It is
671 part of the implementation of the compression library and is
672 subject to change. Applications should only use zlib.h.
675 local int inflate_fast OF((
680 inflate_blocks_statef *,
685 /* infblock.c -- interpret and process block types to last block
686 * Copyright (C) 1995 Mark Adler
687 * For conditions of distribution and use, see copyright notice in zlib.h
690 /* Table for deflate from PKZIP's appnote.txt. */
691 local uInt border[] = { /* Order of the bit length code lengths */
692 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
695 Notes beyond the 1.93a appnote.txt:
697 1. Distance pointers never point before the beginning of the output
699 2. Distance pointers can point back across blocks, up to 32k away.
700 3. There is an implied maximum of 7 bits for the bit length table and
701 15 bits for the actual data.
702 4. If only one code exists, then it is encoded using one bit. (Zero
703 would be more efficient, but perhaps a little confusing.) If two
704 codes exist, they are coded using one bit each (0 and 1).
705 5. There is no way of sending zero distance codes--a dummy must be
706 sent if there are none. (History: a pre 2.0 version of PKZIP would
707 store blocks with no distance codes, but this was discovered to be
708 too harsh a criterion.) Valid only for 1.93a. 2.04c does allow
709 zero distance codes, which is sent as one code of zero bits in
711 6. There are up to 286 literal/length codes. Code 256 represents the
712 end-of-block. Note however that the static length tree defines
713 288 codes just to fill out the Huffman codes. Codes 286 and 287
714 cannot be used though, since there is no length base or extra bits
715 defined for them. Similarily, there are up to 30 distance codes.
716 However, static trees define 32 codes (all 5 bits) to fill out the
717 Huffman codes, but the last two had better not show up in the data.
718 7. Unzip can check dynamic Huffman blocks for complete code sets.
719 The exception is that a single code would not be complete (see #4).
720 8. The five bits following the block type is really the number of
721 literal codes sent minus 257.
722 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
723 (1+6+6). Therefore, to output three times the length, you output
724 three codes (1+1+1), whereas to output four times the same length,
725 you only need two codes (1+3). Hmm.
726 10. In the tree reconstruction algorithm, Code = Code + Increment
727 only if BitLength(i) is not zero. (Pretty obvious.)
728 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19)
729 12. Note: length code 284 can represent 227-258, but length code 285
730 really is 258. The last length deserves its own, short code
731 since it gets used a lot in very redundant files. The length
732 258 is special since 258 - 3 (the min match length) is 255.
733 13. The literal/length and distance code bit lengths are read as a
734 single stream of lengths. It is possible (and advantageous) for
735 a repeat code (16, 17, or 18) to go across the boundary between
736 the two sets of lengths.
740 local void inflate_blocks_reset(s, z, c)
741 inflate_blocks_statef *s;
745 if (s->checkfn != Z_NULL)
747 if (s->mode == BTREE || s->mode == DTREE)
748 ZFREE(z, s->sub.trees.blens, s->sub.trees.nblens * sizeof(uInt));
749 if (s->mode == CODES)
751 inflate_codes_free(s->sub.decode.codes, z);
752 inflate_trees_free(s->sub.decode.td, z);
753 inflate_trees_free(s->sub.decode.tl, z);
758 s->read = s->write = s->window;
759 if (s->checkfn != Z_NULL)
760 s->check = (*s->checkfn)(0L, Z_NULL, 0);
761 Trace((stderr, "inflate: blocks reset\n"));
765 local inflate_blocks_statef *inflate_blocks_new(z, c, w)
770 inflate_blocks_statef *s;
772 if ((s = (inflate_blocks_statef *)ZALLOC
773 (z,1,sizeof(struct inflate_blocks_state))) == Z_NULL)
775 if ((s->window = (Bytef *)ZALLOC(z, 1, w)) == Z_NULL)
777 ZFREE(z, s, sizeof(struct inflate_blocks_state));
780 s->end = s->window + w;
783 Trace((stderr, "inflate: blocks allocated\n"));
784 inflate_blocks_reset(s, z, &s->check);
789 local int inflate_blocks(s, z, r)
790 inflate_blocks_statef *s;
794 uInt t; /* temporary storage */
795 uLong b; /* bit buffer */
796 uInt k; /* bits in bit buffer */
797 Bytef *p; /* input data pointer */
798 uInt n; /* bytes available there */
799 Bytef *q; /* output window write pointer */
800 uInt m; /* bytes to end of window or read pointer */
802 /* copy input/output information to locals (UPDATE macro restores) */
805 /* process input based on current state */
806 while (1) switch (s->mode)
815 Trace((stderr, "inflate: stored block%s\n",
816 s->last ? " (last)" : ""));
818 t = k & 7; /* go to byte boundary */
820 s->mode = LENS; /* get length of stored block */
823 Trace((stderr, "inflate: fixed codes block%s\n",
824 s->last ? " (last)" : ""));
827 inflate_huft *tl, *td;
829 inflate_trees_fixed(&bl, &bd, &tl, &td);
830 s->sub.decode.codes = inflate_codes_new(bl, bd, tl, td, z);
831 if (s->sub.decode.codes == Z_NULL)
836 s->sub.decode.tl = Z_NULL; /* don't try to free these */
837 s->sub.decode.td = Z_NULL;
842 case 2: /* dynamic */
843 Trace((stderr, "inflate: dynamic codes block%s\n",
844 s->last ? " (last)" : ""));
848 case 3: /* illegal */
851 z->msg = "invalid block type";
858 if (((~b) >> 16) != (b & 0xffff))
861 z->msg = "invalid stored block lengths";
865 s->sub.left = (uInt)b & 0xffff;
866 b = k = 0; /* dump bits */
867 Tracev((stderr, "inflate: stored length %u\n", s->sub.left));
868 s->mode = s->sub.left ? STORED : TYPE;
880 if ((s->sub.left -= t) != 0)
882 Tracev((stderr, "inflate: stored end, %lu total out\n",
883 z->total_out + (q >= s->read ? q - s->read :
884 (s->end - s->read) + (q - s->window))));
885 s->mode = s->last ? DRY : TYPE;
889 s->sub.trees.table = t = (uInt)b & 0x3fff;
890 #ifndef PKZIP_BUG_WORKAROUND
891 if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29)
894 z->msg = "too many length or distance symbols";
899 t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
902 if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL)
907 s->sub.trees.nblens = t;
909 s->sub.trees.index = 0;
910 Tracev((stderr, "inflate: table sizes ok\n"));
913 while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10))
916 s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7;
919 while (s->sub.trees.index < 19)
920 s->sub.trees.blens[border[s->sub.trees.index++]] = 0;
922 t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb,
923 &s->sub.trees.tb, z);
927 if (r == Z_DATA_ERROR)
929 ZFREE(z, s->sub.trees.blens, s->sub.trees.nblens * sizeof(uInt));
934 s->sub.trees.index = 0;
935 Tracev((stderr, "inflate: bits tree ok\n"));
938 while (t = s->sub.trees.table,
939 s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f))
946 h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]);
947 t = h->word.what.Bits;
952 s->sub.trees.blens[s->sub.trees.index++] = c;
954 else /* c == 16..18 */
956 i = c == 18 ? 7 : c - 14;
957 j = c == 18 ? 11 : 3;
960 j += (uInt)b & inflate_mask[i];
962 i = s->sub.trees.index;
963 t = s->sub.trees.table;
964 if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) ||
967 ZFREE(z, s->sub.trees.blens, s->sub.trees.nblens * sizeof(uInt));
969 z->msg = "invalid bit length repeat";
973 c = c == 16 ? s->sub.trees.blens[i - 1] : 0;
975 s->sub.trees.blens[i++] = c;
977 s->sub.trees.index = i;
980 inflate_trees_free(s->sub.trees.tb, z);
981 s->sub.trees.tb = Z_NULL;
984 inflate_huft *tl, *td;
985 inflate_codes_statef *c;
987 bl = 9; /* must be <= 9 for lookahead assumptions */
988 bd = 6; /* must be <= 9 for lookahead assumptions */
989 t = s->sub.trees.table;
990 t = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f),
991 s->sub.trees.blens, &bl, &bd, &tl, &td, z);
994 if (t == (uInt)Z_DATA_ERROR)
996 ZFREE(z, s->sub.trees.blens, s->sub.trees.nblens * sizeof(uInt));
1002 Tracev((stderr, "inflate: trees ok\n"));
1003 if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL)
1005 inflate_trees_free(td, z);
1006 inflate_trees_free(tl, z);
1010 ZFREE(z, s->sub.trees.blens, s->sub.trees.nblens * sizeof(uInt));
1011 s->sub.decode.codes = c;
1012 s->sub.decode.tl = tl;
1013 s->sub.decode.td = td;
1018 if ((r = inflate_codes(s, z, r)) != Z_STREAM_END)
1019 return inflate_flush(s, z, r);
1021 inflate_codes_free(s->sub.decode.codes, z);
1022 inflate_trees_free(s->sub.decode.td, z);
1023 inflate_trees_free(s->sub.decode.tl, z);
1025 Tracev((stderr, "inflate: codes end, %lu total out\n",
1026 z->total_out + (q >= s->read ? q - s->read :
1027 (s->end - s->read) + (q - s->window))));
1033 if (k > 7) /* return unused byte, if any */
1035 Assert(k < 16, "inflate_codes grabbed too many bytes")
1038 p--; /* can always return one */
1043 if (s->read != s->write)
1059 local int inflate_blocks_free(s, z, c)
1060 inflate_blocks_statef *s;
1064 inflate_blocks_reset(s, z, c);
1065 ZFREE(z, s->window, s->end - s->window);
1066 ZFREE(z, s, sizeof(struct inflate_blocks_state));
1067 Trace((stderr, "inflate: blocks freed\n"));
1072 * This subroutine adds the data at next_in/avail_in to the output history
1073 * without performing any output. The output buffer must be "caught up";
1074 * i.e. no pending output (hence s->read equals s->write), and the state must
1075 * be BLOCKS (i.e. we should be willing to see the start of a series of
1076 * BLOCKS). On exit, the output will also be caught up, and the checksum
1077 * will have been updated if need be.
1079 local int inflate_addhistory(s, z)
1080 inflate_blocks_statef *s;
1083 uLong b; /* bit buffer */ /* NOT USED HERE */
1084 uInt k; /* bits in bit buffer */ /* NOT USED HERE */
1085 uInt t; /* temporary storage */
1086 Bytef *p; /* input data pointer */
1087 uInt n; /* bytes available there */
1088 Bytef *q; /* output window write pointer */
1089 uInt m; /* bytes to end of window or read pointer */
1091 if (s->read != s->write)
1092 return Z_STREAM_ERROR;
1093 if (s->mode != TYPE)
1094 return Z_DATA_ERROR;
1096 /* we're ready to rock */
1098 /* while there is input ready, copy to output buffer, moving
1099 * pointers as needed.
1102 t = n; /* how many to do */
1103 /* is there room until end of buffer? */
1105 /* update check information */
1106 if (s->checkfn != Z_NULL)
1107 s->check = (*s->checkfn)(s->check, q, t);
1113 s->read = q; /* drag read pointer forward */
1114 /* WRAP */ /* expand WRAP macro by hand to handle s->read */
1116 s->read = q = s->window;
1126 * At the end of a Deflate-compressed PPP packet, we expect to have seen
1127 * a `stored' block type value but not the (zero) length bytes.
1129 local int inflate_packet_flush(s)
1130 inflate_blocks_statef *s;
1132 if (s->mode != LENS)
1133 return Z_DATA_ERROR;
1140 /* inftrees.c -- generate Huffman trees for efficient decoding
1141 * Copyright (C) 1995 Mark Adler
1142 * For conditions of distribution and use, see copyright notice in zlib.h
1145 /* simplify the use of the inflate_huft type with some defines */
1146 #define base more.Base
1147 #define next more.Next
1148 #define exop word.what.Exop
1149 #define bits word.what.Bits
1152 local int huft_build OF((
1153 uIntf *, /* code lengths in bits */
1154 uInt, /* number of codes */
1155 uInt, /* number of "simple" codes */
1156 uIntf *, /* list of base values for non-simple codes */
1157 uIntf *, /* list of extra bits for non-simple codes */
1158 inflate_huft * FAR*,/* result: starting table */
1159 uIntf *, /* maximum lookup bits (returns actual) */
1160 z_stream *)); /* for zalloc function */
1162 local voidpf falloc OF((
1163 voidpf, /* opaque pointer (not used) */
1164 uInt, /* number of items */
1165 uInt)); /* size of item */
1167 local void ffree OF((
1168 voidpf q, /* opaque pointer (not used) */
1169 voidpf p, /* what to free (not used) */
1170 uInt n)); /* number of bytes (not used) */
1172 /* Tables for deflate from PKZIP's appnote.txt. */
1173 local uInt cplens[] = { /* Copy lengths for literal codes 257..285 */
1174 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
1175 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
1176 /* actually lengths - 2; also see note #13 above about 258 */
1177 local uInt cplext[] = { /* Extra bits for literal codes 257..285 */
1178 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
1179 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 192, 192}; /* 192==invalid */
1180 local uInt cpdist[] = { /* Copy offsets for distance codes 0..29 */
1181 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
1182 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
1183 8193, 12289, 16385, 24577};
1184 local uInt cpdext[] = { /* Extra bits for distance codes */
1185 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
1186 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
1190 Huffman code decoding is performed using a multi-level table lookup.
1191 The fastest way to decode is to simply build a lookup table whose
1192 size is determined by the longest code. However, the time it takes
1193 to build this table can also be a factor if the data being decoded
1194 is not very long. The most common codes are necessarily the
1195 shortest codes, so those codes dominate the decoding time, and hence
1196 the speed. The idea is you can have a shorter table that decodes the
1197 shorter, more probable codes, and then point to subsidiary tables for
1198 the longer codes. The time it costs to decode the longer codes is
1199 then traded against the time it takes to make longer tables.
1201 This results of this trade are in the variables lbits and dbits
1202 below. lbits is the number of bits the first level table for literal/
1203 length codes can decode in one step, and dbits is the same thing for
1204 the distance codes. Subsequent tables are also less than or equal to
1205 those sizes. These values may be adjusted either when all of the
1206 codes are shorter than that, in which case the longest code length in
1207 bits is used, or when the shortest code is *longer* than the requested
1208 table size, in which case the length of the shortest code in bits is
1211 There are two different values for the two tables, since they code a
1212 different number of possibilities each. The literal/length table
1213 codes 286 possible values, or in a flat code, a little over eight
1214 bits. The distance table codes 30 possible values, or a little less
1215 than five bits, flat. The optimum values for speed end up being
1216 about one bit more than those, so lbits is 8+1 and dbits is 5+1.
1217 The optimum values may differ though from machine to machine, and
1218 possibly even between compilers. Your mileage may vary.
1222 /* If BMAX needs to be larger than 16, then h and x[] should be uLong. */
1223 #define BMAX 15 /* maximum bit length of any code */
1224 #define N_MAX 288 /* maximum number of codes in any set */
1230 local int huft_build(b, n, s, d, e, t, m, zs)
1231 uIntf *b; /* code lengths in bits (all assumed <= BMAX) */
1232 uInt n; /* number of codes (assumed <= N_MAX) */
1233 uInt s; /* number of simple-valued codes (0..s-1) */
1234 uIntf *d; /* list of base values for non-simple codes */
1235 uIntf *e; /* list of extra bits for non-simple codes */
1236 inflate_huft * FAR *t; /* result: starting table */
1237 uIntf *m; /* maximum lookup bits, returns actual */
1238 z_stream *zs; /* for zalloc function */
1239 /* Given a list of code lengths and a maximum table size, make a set of
1240 tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR
1241 if the given code set is incomplete (the tables are still built in this
1242 case), Z_DATA_ERROR if the input is invalid (all zero length codes or an
1243 over-subscribed set of lengths), or Z_MEM_ERROR if not enough memory. */
1246 uInt a; /* counter for codes of length k */
1247 uInt c[BMAX+1]; /* bit length count table */
1248 uInt f; /* i repeats in table every f entries */
1249 int g; /* maximum code length */
1250 int h; /* table level */
1251 register uInt i; /* counter, current code */
1252 register uInt j; /* counter */
1253 register int k; /* number of bits in current code */
1254 int l; /* bits per table (returned in m) */
1255 register uIntf *p; /* pointer into c[], b[], or v[] */
1256 inflate_huft *q; /* points to current table */
1257 struct inflate_huft_s r; /* table entry for structure assignment */
1258 inflate_huft *u[BMAX]; /* table stack */
1259 uInt v[N_MAX]; /* values in order of bit length */
1260 register int w; /* bits before this table == (l * h) */
1261 uInt x[BMAX+1]; /* bit offsets, then code stack */
1262 uIntf *xp; /* pointer into x */
1263 int y; /* number of dummy codes added */
1264 uInt z; /* number of entries in current table */
1267 /* Generate counts for each bit length */
1269 #define C0 *p++ = 0;
1270 #define C2 C0 C0 C0 C0
1271 #define C4 C2 C2 C2 C2
1272 C4 /* clear c[]--assume BMAX+1 is 16 */
1275 c[*p++]++; /* assume all entries <= BMAX */
1277 if (c[0] == n) /* null input--all zero length codes */
1279 *t = (inflate_huft *)Z_NULL;
1285 /* Find minimum and maximum length, bound *m by those */
1287 for (j = 1; j <= BMAX; j++)
1290 k = j; /* minimum code length */
1293 for (i = BMAX; i; i--)
1296 g = i; /* maximum code length */
1302 /* Adjust last length count to fill out codes, if needed */
1303 for (y = 1 << j; j < i; j++, y <<= 1)
1304 if ((y -= c[j]) < 0)
1305 return Z_DATA_ERROR;
1306 if ((y -= c[i]) < 0)
1307 return Z_DATA_ERROR;
1311 /* Generate starting offsets into the value table for each length */
1313 p = c + 1; xp = x + 2;
1314 while (--i) { /* note that i == g from above */
1315 *xp++ = (j += *p++);
1319 /* Make a table of values in order of bit lengths */
1322 if ((j = *p++) != 0)
1327 /* Generate the Huffman codes and for each, make the table entries */
1328 x[0] = i = 0; /* first Huffman code is zero */
1329 p = v; /* grab values in bit order */
1330 h = -1; /* no tables yet--level -1 */
1331 w = -l; /* bits decoded == (l * h) */
1332 u[0] = (inflate_huft *)Z_NULL; /* just to keep compilers happy */
1333 q = (inflate_huft *)Z_NULL; /* ditto */
1336 /* go through the bit lengths (k already is bits in shortest code) */
1342 /* here i is the Huffman code of length k bits for value *p */
1343 /* make tables up to required level */
1347 w += l; /* previous table always l bits */
1349 /* compute minimum size table less than or equal to l bits */
1350 z = (z = g - w) > (uInt)l ? l : z; /* table size upper limit */
1351 if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */
1352 { /* too few codes for k-w bit table */
1353 f -= a + 1; /* deduct codes from patterns left */
1356 while (++j < z) /* try smaller tables up to z bits */
1358 if ((f <<= 1) <= *++xp)
1359 break; /* enough codes to use up j bits */
1360 f -= *xp; /* else deduct codes from patterns */
1363 z = 1 << j; /* table entries for j-bit table */
1365 /* allocate and link in new table */
1366 if ((q = (inflate_huft *)ZALLOC
1367 (zs,z + 1,sizeof(inflate_huft))) == Z_NULL)
1370 inflate_trees_free(u[0], zs);
1371 return Z_MEM_ERROR; /* not enough memory */
1373 q->word.Nalloc = z + 1;
1375 inflate_hufts += z + 1;
1377 *t = q + 1; /* link to list for huft_free() */
1378 *(t = &(q->next)) = Z_NULL;
1379 u[h] = ++q; /* table starts after link */
1381 /* connect to last table, if there is one */
1384 x[h] = i; /* save pattern for backing up */
1385 r.bits = (Byte)l; /* bits to dump before this table */
1386 r.exop = (Byte)j; /* bits in this table */
1387 r.next = q; /* pointer to this table */
1388 j = i >> (w - l); /* (get around Turbo C bug) */
1389 u[h-1][j] = r; /* connect to last table */
1393 /* set up table entry in r */
1394 r.bits = (Byte)(k - w);
1396 r.exop = 128 + 64; /* out of values--invalid code */
1399 r.exop = (Byte)(*p < 256 ? 0 : 32 + 64); /* 256 is end-of-block */
1400 r.base = *p++; /* simple code is just the value */
1404 r.exop = (Byte)e[*p - s] + 16 + 64; /* non-simple--look up in lists */
1405 r.base = d[*p++ - s];
1408 /* fill code-like entries with r */
1410 for (j = i >> w; j < z; j += f)
1413 /* backwards increment the k-bit code i */
1414 for (j = 1 << (k - 1); i & j; j >>= 1)
1418 /* backup over finished tables */
1419 while ((i & ((1 << w) - 1)) != x[h])
1421 h--; /* don't need to update q */
1428 /* Return Z_BUF_ERROR if we were given an incomplete table */
1429 return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK;
1433 local int inflate_trees_bits(c, bb, tb, z)
1434 uIntf *c; /* 19 code lengths */
1435 uIntf *bb; /* bits tree desired/actual depth */
1436 inflate_huft * FAR *tb; /* bits tree result */
1437 z_stream *z; /* for zfree function */
1441 r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL, tb, bb, z);
1442 if (r == Z_DATA_ERROR)
1443 z->msg = "oversubscribed dynamic bit lengths tree";
1444 else if (r == Z_BUF_ERROR)
1446 inflate_trees_free(*tb, z);
1447 z->msg = "incomplete dynamic bit lengths tree";
1454 local int inflate_trees_dynamic(nl, nd, c, bl, bd, tl, td, z)
1455 uInt nl; /* number of literal/length codes */
1456 uInt nd; /* number of distance codes */
1457 uIntf *c; /* that many (total) code lengths */
1458 uIntf *bl; /* literal desired/actual bit depth */
1459 uIntf *bd; /* distance desired/actual bit depth */
1460 inflate_huft * FAR *tl; /* literal/length tree result */
1461 inflate_huft * FAR *td; /* distance tree result */
1462 z_stream *z; /* for zfree function */
1466 /* build literal/length tree */
1467 if ((r = huft_build(c, nl, 257, cplens, cplext, tl, bl, z)) != Z_OK)
1469 if (r == Z_DATA_ERROR)
1470 z->msg = "oversubscribed literal/length tree";
1471 else if (r == Z_BUF_ERROR)
1473 inflate_trees_free(*tl, z);
1474 z->msg = "incomplete literal/length tree";
1480 /* build distance tree */
1481 if ((r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, z)) != Z_OK)
1483 if (r == Z_DATA_ERROR)
1484 z->msg = "oversubscribed literal/length tree";
1485 else if (r == Z_BUF_ERROR) {
1486 #ifdef PKZIP_BUG_WORKAROUND
1490 inflate_trees_free(*td, z);
1491 z->msg = "incomplete literal/length tree";
1494 inflate_trees_free(*tl, z);
1504 /* build fixed tables only once--keep them here */
1505 local int fixed_lock = 0;
1506 local int fixed_built = 0;
1507 #define FIXEDH 530 /* number of hufts used by fixed tables */
1508 local uInt fixed_left = FIXEDH;
1509 local inflate_huft fixed_mem[FIXEDH];
1510 local uInt fixed_bl;
1511 local uInt fixed_bd;
1512 local inflate_huft *fixed_tl;
1513 local inflate_huft *fixed_td;
1516 local voidpf falloc(q, n, s)
1517 voidpf q; /* opaque pointer (not used) */
1518 uInt n; /* number of items */
1519 uInt s; /* size of item */
1521 Assert(s == sizeof(inflate_huft) && n <= fixed_left,
1522 "inflate_trees falloc overflow");
1523 if (q) s++; /* to make some compilers happy */
1525 return (voidpf)(fixed_mem + fixed_left);
1529 local void ffree(q, p, n)
1534 Assert(0, "inflate_trees ffree called!");
1535 if (q) q = p; /* to make some compilers happy */
1539 local int inflate_trees_fixed(bl, bd, tl, td)
1540 uIntf *bl; /* literal desired/actual bit depth */
1541 uIntf *bd; /* distance desired/actual bit depth */
1542 inflate_huft * FAR *tl; /* literal/length tree result */
1543 inflate_huft * FAR *td; /* distance tree result */
1545 /* build fixed tables if not built already--lock out other instances */
1546 while (++fixed_lock > 1)
1550 int k; /* temporary variable */
1551 unsigned c[288]; /* length list for huft_build */
1552 z_stream z; /* for falloc function */
1554 /* set up fake z_stream for memory routines */
1560 for (k = 0; k < 144; k++)
1562 for (; k < 256; k++)
1564 for (; k < 280; k++)
1566 for (; k < 288; k++)
1569 huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl, &z);
1571 /* distance table */
1572 for (k = 0; k < 30; k++)
1575 huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd, &z);
1589 local int inflate_trees_free(t, z)
1590 inflate_huft *t; /* table to free */
1591 z_stream *z; /* for zfree function */
1592 /* Free the malloc'ed tables built by huft_build(), which makes a linked
1593 list of the tables it made, with the links in a dummy first entry of
1596 register inflate_huft *p, *q;
1598 /* Go through linked list, freeing from the malloced (t[-1]) address. */
1603 ZFREE(z, p, p->word.Nalloc * sizeof(inflate_huft));
1610 /* infcodes.c -- process literals and length/distance pairs
1611 * Copyright (C) 1995 Mark Adler
1612 * For conditions of distribution and use, see copyright notice in zlib.h
1615 /* simplify the use of the inflate_huft type with some defines */
1616 #define base more.Base
1617 #define next more.Next
1618 #define exop word.what.Exop
1619 #define bits word.what.Bits
1621 /* inflate codes private state */
1622 struct inflate_codes_state {
1625 enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
1626 START, /* x: set up for LEN */
1627 LEN, /* i: get length/literal/eob next */
1628 LENEXT, /* i: getting length extra (have base) */
1629 DIST, /* i: get distance next */
1630 DISTEXT, /* i: getting distance extra */
1631 COPY, /* o: copying bytes in window, waiting for space */
1632 LIT, /* o: got literal, waiting for output space */
1633 WASH, /* o: got eob, possibly still output waiting */
1634 END, /* x: got eob and all data flushed */
1635 BADCODE} /* x: got error */
1636 mode; /* current inflate_codes mode */
1638 /* mode dependent information */
1642 inflate_huft *tree; /* pointer into tree */
1643 uInt need; /* bits needed */
1644 } code; /* if LEN or DIST, where in tree */
1645 uInt lit; /* if LIT, literal */
1647 uInt get; /* bits to get for extra */
1648 uInt dist; /* distance back to copy from */
1649 } copy; /* if EXT or COPY, where and how much */
1650 } sub; /* submode */
1652 /* mode independent information */
1653 Byte lbits; /* ltree bits decoded per branch */
1654 Byte dbits; /* dtree bits decoder per branch */
1655 inflate_huft *ltree; /* literal/length/eob tree */
1656 inflate_huft *dtree; /* distance tree */
1661 local inflate_codes_statef *inflate_codes_new(bl, bd, tl, td, z)
1663 inflate_huft *tl, *td;
1666 inflate_codes_statef *c;
1668 if ((c = (inflate_codes_statef *)
1669 ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL)
1672 c->lbits = (Byte)bl;
1673 c->dbits = (Byte)bd;
1676 Tracev((stderr, "inflate: codes new\n"));
1682 local int inflate_codes(s, z, r)
1683 inflate_blocks_statef *s;
1687 uInt j; /* temporary storage */
1688 inflate_huft *t; /* temporary pointer */
1689 uInt e; /* extra bits or operation */
1690 uLong b; /* bit buffer */
1691 uInt k; /* bits in bit buffer */
1692 Bytef *p; /* input data pointer */
1693 uInt n; /* bytes available there */
1694 Bytef *q; /* output window write pointer */
1695 uInt m; /* bytes to end of window or read pointer */
1696 Bytef *f; /* pointer to copy strings from */
1697 inflate_codes_statef *c = s->sub.decode.codes; /* codes state */
1699 /* copy input/output information to locals (UPDATE macro restores) */
1702 /* process input and output based on current state */
1703 while (1) switch (c->mode)
1704 { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
1705 case START: /* x: set up for LEN */
1707 if (m >= 258 && n >= 10)
1710 r = inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z);
1714 c->mode = r == Z_STREAM_END ? WASH : BADCODE;
1719 c->sub.code.need = c->lbits;
1720 c->sub.code.tree = c->ltree;
1722 case LEN: /* i: get length/literal/eob next */
1723 j = c->sub.code.need;
1725 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
1727 e = (uInt)(t->exop);
1728 if (e == 0) /* literal */
1730 c->sub.lit = t->base;
1731 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
1732 "inflate: literal '%c'\n" :
1733 "inflate: literal 0x%02x\n", t->base));
1737 if (e & 16) /* length */
1739 c->sub.copy.get = e & 15;
1744 if ((e & 64) == 0) /* next table */
1746 c->sub.code.need = e;
1747 c->sub.code.tree = t->next;
1750 if (e & 32) /* end of block */
1752 Tracevv((stderr, "inflate: end of block\n"));
1756 c->mode = BADCODE; /* invalid code */
1757 z->msg = "invalid literal/length code";
1760 case LENEXT: /* i: getting length extra (have base) */
1761 j = c->sub.copy.get;
1763 c->len += (uInt)b & inflate_mask[j];
1765 c->sub.code.need = c->dbits;
1766 c->sub.code.tree = c->dtree;
1767 Tracevv((stderr, "inflate: length %u\n", c->len));
1769 case DIST: /* i: get distance next */
1770 j = c->sub.code.need;
1772 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
1774 e = (uInt)(t->exop);
1775 if (e & 16) /* distance */
1777 c->sub.copy.get = e & 15;
1778 c->sub.copy.dist = t->base;
1782 if ((e & 64) == 0) /* next table */
1784 c->sub.code.need = e;
1785 c->sub.code.tree = t->next;
1788 c->mode = BADCODE; /* invalid code */
1789 z->msg = "invalid distance code";
1792 case DISTEXT: /* i: getting distance extra */
1793 j = c->sub.copy.get;
1795 c->sub.copy.dist += (uInt)b & inflate_mask[j];
1797 Tracevv((stderr, "inflate: distance %u\n", c->sub.copy.dist));
1799 case COPY: /* o: copying bytes in window, waiting for space */
1800 #ifndef __TURBOC__ /* Turbo C bug for following expression */
1801 f = (uInt)(q - s->window) < c->sub.copy.dist ?
1802 s->end - (c->sub.copy.dist - (q - s->window)) :
1803 q - c->sub.copy.dist;
1805 f = q - c->sub.copy.dist;
1806 if ((uInt)(q - s->window) < c->sub.copy.dist)
1807 f = s->end - (c->sub.copy.dist - (q - s->window));
1819 case LIT: /* o: got literal, waiting for output space */
1824 case WASH: /* o: got eob, possibly more output */
1826 if (s->read != s->write)
1832 case BADCODE: /* x: got error */
1842 local void inflate_codes_free(c, z)
1843 inflate_codes_statef *c;
1846 ZFREE(z, c, sizeof(struct inflate_codes_state));
1847 Tracev((stderr, "inflate: codes free\n"));
1851 /* inflate_util.c -- data and routines common to blocks and codes
1852 * Copyright (C) 1995 Mark Adler
1853 * For conditions of distribution and use, see copyright notice in zlib.h
1856 /* copy as much as possible from the sliding window to the output area */
1857 local int inflate_flush(s, z, r)
1858 inflate_blocks_statef *s;
1865 /* local copies of source and destination pointers */
1869 /* compute number of bytes to copy as far as end of window */
1870 n = (uInt)((q <= s->write ? s->write : s->end) - q);
1871 if (n > z->avail_out) n = z->avail_out;
1872 if (n && r == Z_BUF_ERROR) r = Z_OK;
1874 /* update counters */
1878 /* update check information */
1879 if (s->checkfn != Z_NULL)
1880 s->check = (*s->checkfn)(s->check, q, n);
1882 /* copy as far as end of window */
1887 /* see if more to copy at beginning of window */
1892 if (s->write == s->end)
1893 s->write = s->window;
1895 /* compute bytes to copy */
1896 n = (uInt)(s->write - q);
1897 if (n > z->avail_out) n = z->avail_out;
1898 if (n && r == Z_BUF_ERROR) r = Z_OK;
1900 /* update counters */
1904 /* update check information */
1905 if (s->checkfn != Z_NULL)
1906 s->check = (*s->checkfn)(s->check, q, n);
1914 /* update pointers */
1924 /* inffast.c -- process literals and length/distance pairs fast
1925 * Copyright (C) 1995 Mark Adler
1926 * For conditions of distribution and use, see copyright notice in zlib.h
1929 /* simplify the use of the inflate_huft type with some defines */
1930 #define base more.Base
1931 #define next more.Next
1932 #define exop word.what.Exop
1933 #define bits word.what.Bits
1935 /* macros for bit input with no checking and for returning unused bytes */
1936 #define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}}
1937 #define UNGRAB {n+=(c=k>>3);p-=c;k&=7;}
1939 /* Called with number of bytes left to write in window at least 258
1940 (the maximum string length) and number of input bytes available
1941 at least ten. The ten bytes are six bytes for the longest length/
1942 distance pair plus four bytes for overloading the bit buffer. */
1944 local int inflate_fast(bl, bd, tl, td, s, z)
1946 inflate_huft *tl, *td;
1947 inflate_blocks_statef *s;
1950 inflate_huft *t; /* temporary pointer */
1951 uInt e; /* extra bits or operation */
1952 uLong b; /* bit buffer */
1953 uInt k; /* bits in bit buffer */
1954 Bytef *p; /* input data pointer */
1955 uInt n; /* bytes available there */
1956 Bytef *q; /* output window write pointer */
1957 uInt m; /* bytes to end of window or read pointer */
1958 uInt ml; /* mask for literal/length tree */
1959 uInt md; /* mask for distance tree */
1960 uInt c; /* bytes to copy */
1961 uInt d; /* distance back to copy from */
1962 Bytef *r; /* copy source pointer */
1964 /* load input, output, bit values */
1967 /* initialize masks */
1968 ml = inflate_mask[bl];
1969 md = inflate_mask[bd];
1971 /* do until not enough input or output space for fast loop */
1972 do { /* assume called with m >= 258 && n >= 10 */
1973 /* get literal/length code */
1974 GRABBITS(20) /* max bits for literal/length code */
1975 if ((e = (t = tl + ((uInt)b & ml))->exop) == 0)
1978 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
1979 "inflate: * literal '%c'\n" :
1980 "inflate: * literal 0x%02x\n", t->base));
1981 *q++ = (Byte)t->base;
1989 /* get extra bits for length */
1991 c = t->base + ((uInt)b & inflate_mask[e]);
1993 Tracevv((stderr, "inflate: * length %u\n", c));
1995 /* decode distance base of block to copy */
1996 GRABBITS(15); /* max bits for distance code */
1997 e = (t = td + ((uInt)b & md))->exop;
2002 /* get extra bits to add to distance base */
2004 GRABBITS(e) /* get extra bits (up to 13) */
2005 d = t->base + ((uInt)b & inflate_mask[e]);
2007 Tracevv((stderr, "inflate: * distance %u\n", d));
2011 if ((uInt)(q - s->window) >= d) /* offset before dest */
2014 *q++ = *r++; c--; /* minimum count is three, */
2015 *q++ = *r++; c--; /* so unroll loop a little */
2017 else /* else offset after destination */
2019 e = d - (q - s->window); /* bytes from offset to end */
2020 r = s->end - e; /* pointer to offset */
2021 if (c > e) /* if source crosses, */
2023 c -= e; /* copy to end of window */
2027 r = s->window; /* copy rest from start of window */
2030 do { /* copy all or what's left */
2035 else if ((e & 64) == 0)
2036 e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop;
2039 z->msg = "invalid distance code";
2042 return Z_DATA_ERROR;
2049 if ((e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop) == 0)
2052 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
2053 "inflate: * literal '%c'\n" :
2054 "inflate: * literal 0x%02x\n", t->base));
2055 *q++ = (Byte)t->base;
2062 Tracevv((stderr, "inflate: * end of block\n"));
2065 return Z_STREAM_END;
2069 z->msg = "invalid literal/length code";
2072 return Z_DATA_ERROR;
2075 } while (m >= 258 && n >= 10);
2077 /* not enough input or output--restore pointers and return */
2085 /* zutil.c -- target dependent utility functions for the compression library
2086 * Copyright (C) 1995 Jean-loup Gailly.
2087 * For conditions of distribution and use, see copyright notice in zlib.h
2090 /* From: zutil.c,v 1.8 1995/05/03 17:27:12 jloup Exp */
2092 char *zlib_version = ZLIB_VERSION;
2094 char *z_errmsg[] = {
2095 "stream end", /* Z_STREAM_END 1 */
2097 "file error", /* Z_ERRNO (-1) */
2098 "stream error", /* Z_STREAM_ERROR (-2) */
2099 "data error", /* Z_DATA_ERROR (-3) */
2100 "insufficient memory", /* Z_MEM_ERROR (-4) */
2101 "buffer error", /* Z_BUF_ERROR (-5) */
2106 /* adler32.c -- compute the Adler-32 checksum of a data stream
2107 * Copyright (C) 1995 Mark Adler
2108 * For conditions of distribution and use, see copyright notice in zlib.h
2111 /* From: adler32.c,v 1.6 1995/05/03 17:27:08 jloup Exp */
2113 #define BASE 65521L /* largest prime smaller than 65536 */
2115 /* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
2117 #define DO1(buf) {s1 += *buf++; s2 += s1;}
2118 #define DO2(buf) DO1(buf); DO1(buf);
2119 #define DO4(buf) DO2(buf); DO2(buf);
2120 #define DO8(buf) DO4(buf); DO4(buf);
2121 #define DO16(buf) DO8(buf); DO8(buf);
2123 /* ========================================================================= */
2124 uLong adler32(adler, buf, len)
2129 unsigned long s1 = adler & 0xffff;
2130 unsigned long s2 = (adler >> 16) & 0xffff;
2133 if (buf == Z_NULL) return 1L;
2136 k = len < NMAX ? len : NMAX;
2148 return (s2 << 16) | s1;