+++ /dev/null
-/* explode.c -- put in the public domain by Mark Adler
- version c15, 6 July 1996 */
-
-
-/* You can do whatever you like with this source file, though I would
- prefer that if you modify it and redistribute it that you include
- comments to that effect with your name and the date. Thank you.
-
- History:
- vers date who what
- ---- --------- -------------- ------------------------------------
- c1 30 Mar 92 M. Adler explode that uses huft_build from inflate
- (this gives over a 70% speed improvement
- over the original unimplode.c, which
- decoded a bit at a time)
- c2 4 Apr 92 M. Adler fixed bug for file sizes a multiple of 32k.
- c3 10 Apr 92 M. Adler added a little memory tracking if DEBUG
- c4 11 Apr 92 M. Adler added NOMEMCPY do kill use of memcpy()
- c5 21 Apr 92 M. Adler added the WSIZE #define to allow reducing
- the 32K window size for specialized
- applications.
- c6 31 May 92 M. Adler added typecasts to eliminate some warnings
- c7 27 Jun 92 G. Roelofs added more typecasts.
- c8 17 Oct 92 G. Roelofs changed ULONG/UWORD/byte to ulg/ush/uch.
- c9 19 Jul 93 J. Bush added more typecasts (to return values);
- made l[256] array static for Amiga.
- c10 8 Oct 93 G. Roelofs added used_csize for diagnostics; added
- buf and unshrink arguments to flush();
- undef'd various macros at end for Turbo C;
- removed NEXTBYTE macro (now in unzip.h)
- and bytebuf variable (not used); changed
- memset() to memzero().
- c11 9 Jan 94 M. Adler fixed incorrect used_csize calculation.
- c12 9 Apr 94 G. Roelofs fixed split comments on preprocessor lines
- to avoid bug in Encore compiler.
- c13 25 Aug 94 M. Adler fixed distance-length comment (orig c9 fix)
- c14 22 Nov 95 S. Maxwell removed unnecessary "static" on auto array
- c15 6 Jul 96 W. Haidinger added ulg typecasts to flush() calls.
- c16 8 Feb 98 C. Spieler added ZCONST modifiers to const tables
- and #ifdef DEBUG around debugging code.
- c16b 25 Mar 98 C. Spieler modified DLL code for slide redirection.
- */
-
-
-/*
- Explode imploded (PKZIP method 6 compressed) data. This compression
- method searches for as much of the current string of bytes (up to a length
- of ~320) in the previous 4K or 8K bytes. If it doesn't find any matches
- (of at least length 2 or 3), it codes the next byte. Otherwise, it codes
- the length of the matched string and its distance backwards from the
- current position. Single bytes ("literals") are preceded by a one (a
- single bit) and are either uncoded (the eight bits go directly into the
- compressed stream for a total of nine bits) or Huffman coded with a
- supplied literal code tree. If literals are coded, then the minimum match
- length is three, otherwise it is two.
-
- There are therefore four kinds of imploded streams: 8K search with coded
- literals (min match = 3), 4K search with coded literals (min match = 3),
- 8K with uncoded literals (min match = 2), and 4K with uncoded literals
- (min match = 2). The kind of stream is identified in two bits of a
- general purpose bit flag that is outside of the compressed stream.
-
- Distance-length pairs for matched strings are preceded by a zero bit (to
- distinguish them from literals) and are always coded. The distance comes
- first and is either the low six (4K) or low seven (8K) bits of the
- distance (uncoded), followed by the high six bits of the distance coded.
- Then the length is six bits coded (0..63 + min match length), and if the
- maximum such length is coded, then it's followed by another eight bits
- (uncoded) to be added to the coded length. This gives a match length
- range of 2..320 or 3..321 bytes.
-
- The literal, length, and distance codes are all represented in a slightly
- compressed form themselves. What is sent are the lengths of the codes for
- each value, which is sufficient to construct the codes. Each byte of the
- code representation is the code length (the low four bits representing
- 1..16), and the number of values sequentially with that length (the high
- four bits also representing 1..16). There are 256 literal code values (if
- literals are coded), 64 length code values, and 64 distance code values,
- in that order at the beginning of the compressed stream. Each set of code
- values is preceded (redundantly) with a byte indicating how many bytes are
- in the code description that follows, in the range 1..256.
-
- The codes themselves are decoded using tables made by huft_build() from
- the bit lengths. That routine and its comments are in the inflate.c
- module.
- */
-
-#define UNZIP_INTERNAL
-#include "unzip.h" /* must supply slide[] (uch) array and NEXTBYTE macro */
-
-#ifndef WSIZE
-# define WSIZE 0x8000 /* window size--must be a power of two, and */
-#endif /* at least 8K for zip's implode method */
-
-#if (defined(DLL) && !defined(NO_SLIDE_REDIR))
-# define wsize G._wsize
-#else
-# define wsize WSIZE
-#endif
-
-/* routines here */
-static int get_tree OF((__GPRO__ unsigned *l, unsigned n));
-static int explode_lit8 OF((__GPRO__ struct huft *tb, struct huft *tl,
- struct huft *td, int bb, int bl, int bd));
-static int explode_lit4 OF((__GPRO__ struct huft *tb, struct huft *tl,
- struct huft *td, int bb, int bl, int bd));
-static int explode_nolit8 OF((__GPRO__ struct huft *tl, struct huft *td,
- int bl, int bd));
-static int explode_nolit4 OF((__GPRO__ struct huft *tl, struct huft *td,
- int bl, int bd));
-int explode OF((__GPRO));
-
-
-/* The implode algorithm uses a sliding 4K or 8K byte window on the
- uncompressed stream to find repeated byte strings. This is implemented
- here as a circular buffer. The index is updated simply by incrementing
- and then and'ing with 0x0fff (4K-1) or 0x1fff (8K-1). Here, the 32K
- buffer of inflate is used, and it works just as well to always have
- a 32K circular buffer, so the index is anded with 0x7fff. This is
- done to allow the window to also be used as the output buffer. */
-/* This must be supplied in an external module useable like "uch slide[8192];"
- or "uch *slide;", where the latter would be malloc'ed. In unzip, slide[]
- is actually a 32K area for use by inflate, which uses a 32K sliding window.
- */
-
-
-/* Tables for length and distance */
-static ZCONST ush cplen2[] =
- {2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
- 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34,
- 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,
- 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65};
-static ZCONST ush cplen3[] =
- {3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,
- 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,
- 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52,
- 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66};
-static ZCONST ush extra[] =
- {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 8};
-static ZCONST ush cpdist4[] =
- {1, 65, 129, 193, 257, 321, 385, 449, 513, 577, 641, 705,
- 769, 833, 897, 961, 1025, 1089, 1153, 1217, 1281, 1345, 1409, 1473,
- 1537, 1601, 1665, 1729, 1793, 1857, 1921, 1985, 2049, 2113, 2177,
- 2241, 2305, 2369, 2433, 2497, 2561, 2625, 2689, 2753, 2817, 2881,
- 2945, 3009, 3073, 3137, 3201, 3265, 3329, 3393, 3457, 3521, 3585,
- 3649, 3713, 3777, 3841, 3905, 3969, 4033};
-static ZCONST ush cpdist8[] =
- {1, 129, 257, 385, 513, 641, 769, 897, 1025, 1153, 1281,
- 1409, 1537, 1665, 1793, 1921, 2049, 2177, 2305, 2433, 2561, 2689,
- 2817, 2945, 3073, 3201, 3329, 3457, 3585, 3713, 3841, 3969, 4097,
- 4225, 4353, 4481, 4609, 4737, 4865, 4993, 5121, 5249, 5377, 5505,
- 5633, 5761, 5889, 6017, 6145, 6273, 6401, 6529, 6657, 6785, 6913,
- 7041, 7169, 7297, 7425, 7553, 7681, 7809, 7937, 8065};
-
-
-/* Macros for inflate() bit peeking and grabbing.
- The usage is:
-
- NEEDBITS(j)
- x = b & mask_bits[j];
- DUMPBITS(j)
-
- where NEEDBITS makes sure that b has at least j bits in it, and
- DUMPBITS removes the bits from b. The macros use the variable k
- for the number of bits in b. Normally, b and k are register
- variables for speed.
- */
-
-#define NEEDBITS(n) {while(k<(n)){b|=((ulg)NEXTBYTE)<<k;k+=8;}}
-#define DUMPBITS(n) {b>>=(n);k-=(n);}
-
-
-
-static int get_tree(__G__ l, n)
- __GDEF
-unsigned *l; /* bit lengths */
-unsigned n; /* number expected */
-/* Get the bit lengths for a code representation from the compressed
- stream. If get_tree() returns 4, then there is an error in the data.
- Otherwise zero is returned. */
-{
- unsigned i; /* bytes remaining in list */
- unsigned k; /* lengths entered */
- unsigned j; /* number of codes */
- unsigned b; /* bit length for those codes */
-
-
- /* get bit lengths */
- i = NEXTBYTE + 1; /* length/count pairs to read */
- k = 0; /* next code */
- do {
- b = ((j = NEXTBYTE) & 0xf) + 1; /* bits in code (1..16) */
- j = ((j & 0xf0) >> 4) + 1; /* codes with those bits (1..16) */
- if (k + j > n)
- return 4; /* don't overflow l[] */
- do {
- l[k++] = b;
- } while (--j);
- } while (--i);
- return k != n ? 4 : 0; /* should have read n of them */
-}
-
-
-
-static int explode_lit8(__G__ tb, tl, td, bb, bl, bd)
- __GDEF
-struct huft *tb, *tl, *td; /* literal, length, and distance tables */
-int bb, bl, bd; /* number of bits decoded by those */
-/* Decompress the imploded data using coded literals and an 8K sliding
- window. */
-{
- long s; /* bytes to decompress */
- register unsigned e; /* table entry flag/number of extra bits */
- unsigned n, d; /* length and index for copy */
- unsigned w; /* current window position */
- struct huft *t; /* pointer to table entry */
- unsigned mb, ml, md; /* masks for bb, bl, and bd bits */
- register ulg b; /* bit buffer */
- register unsigned k; /* number of bits in bit buffer */
- unsigned u; /* true if unflushed */
-
-
- /* explode the coded data */
- b = k = w = 0; /* initialize bit buffer, window */
- u = 1; /* buffer unflushed */
- mb = mask_bits[bb]; /* precompute masks for speed */
- ml = mask_bits[bl];
- md = mask_bits[bd];
- s = G.ucsize;
- while (s > 0) /* do until ucsize bytes uncompressed */
- {
- NEEDBITS(1)
- if (b & 1) /* then literal--decode it */
- {
- DUMPBITS(1)
- s--;
- NEEDBITS((unsigned)bb) /* get coded literal */
- if ((e = (t = tb + ((~(unsigned)b) & mb))->e) > 16)
- do {
- if (e == 99)
- return 1;
- DUMPBITS(t->b)
- e -= 16;
- NEEDBITS(e)
- } while ((e = (t = t->v.t + ((~(unsigned)b) & mask_bits[e]))->e) > 16);
- DUMPBITS(t->b)
- redirSlide[w++] = (uch)t->v.n;
- if (w == wsize)
- {
- flush(__G__ redirSlide, (ulg)w, 0);
- w = u = 0;
- }
- }
- else /* else distance/length */
- {
- DUMPBITS(1)
- NEEDBITS(7) /* get distance low bits */
- d = (unsigned)b & 0x7f;
- DUMPBITS(7)
- NEEDBITS((unsigned)bd) /* get coded distance high bits */
- if ((e = (t = td + ((~(unsigned)b) & md))->e) > 16)
- do {
- if (e == 99)
- return 1;
- DUMPBITS(t->b)
- e -= 16;
- NEEDBITS(e)
- } while ((e = (t = t->v.t + ((~(unsigned)b) & mask_bits[e]))->e) > 16);
- DUMPBITS(t->b)
- d = w - d - t->v.n; /* construct offset */
- NEEDBITS((unsigned)bl) /* get coded length */
- if ((e = (t = tl + ((~(unsigned)b) & ml))->e) > 16)
- do {
- if (e == 99)
- return 1;
- DUMPBITS(t->b)
- e -= 16;
- NEEDBITS(e)
- } while ((e = (t = t->v.t + ((~(unsigned)b) & mask_bits[e]))->e) > 16);
- DUMPBITS(t->b)
- n = t->v.n;
- if (e) /* get length extra bits */
- {
- NEEDBITS(8)
- n += (unsigned)b & 0xff;
- DUMPBITS(8)
- }
-
- /* do the copy */
- s -= n;
- do {
-#if (defined(DLL) && !defined(NO_SLIDE_REDIR))
- if (G.redirect_slide) {
- /* &= w/ wsize not needed and wrong if redirect */
- if (d >= wsize)
- return 1;
- n -= (e = (e = wsize - (d > w ? d : w)) > n ? n : e);
- } else
-#endif
- n -= (e = (e = wsize - ((d &= wsize-1) > w ? d : w)) > n ? n : e);
- if (u && w <= d)
- {
- memzero(redirSlide + w, e);
- w += e;
- d += e;
- }
- else
-#ifndef NOMEMCPY
- if (w - d >= e) /* (this test assumes unsigned comparison) */
- {
- memcpy(redirSlide + w, redirSlide + d, e);
- w += e;
- d += e;
- }
- else /* do it slow to avoid memcpy() overlap */
-#endif /* !NOMEMCPY */
- do {
- redirSlide[w++] = redirSlide[d++];
- } while (--e);
- if (w == wsize)
- {
- flush(__G__ redirSlide, (ulg)w, 0);
- w = u = 0;
- }
- } while (n);
- }
- }
-
- /* flush out redirSlide */
- flush(__G__ redirSlide, (ulg)w, 0);
- if (G.csize + G.incnt + (k >> 3)) /* should have read csize bytes, but */
- { /* sometimes read one too many: k>>3 compensates */
- G.used_csize = G.lrec.csize - G.csize - G.incnt - (k >> 3);
- return 5;
- }
- return 0;
-}
-
-
-
-static int explode_lit4(__G__ tb, tl, td, bb, bl, bd)
- __GDEF
-struct huft *tb, *tl, *td; /* literal, length, and distance tables */
-int bb, bl, bd; /* number of bits decoded by those */
-/* Decompress the imploded data using coded literals and a 4K sliding
- window. */
-{
- long s; /* bytes to decompress */
- register unsigned e; /* table entry flag/number of extra bits */
- unsigned n, d; /* length and index for copy */
- unsigned w; /* current window position */
- struct huft *t; /* pointer to table entry */
- unsigned mb, ml, md; /* masks for bb, bl, and bd bits */
- register ulg b; /* bit buffer */
- register unsigned k; /* number of bits in bit buffer */
- unsigned u; /* true if unflushed */
-
-
- /* explode the coded data */
- b = k = w = 0; /* initialize bit buffer, window */
- u = 1; /* buffer unflushed */
- mb = mask_bits[bb]; /* precompute masks for speed */
- ml = mask_bits[bl];
- md = mask_bits[bd];
- s = G.ucsize;
- while (s > 0) /* do until ucsize bytes uncompressed */
- {
- NEEDBITS(1)
- if (b & 1) /* then literal--decode it */
- {
- DUMPBITS(1)
- s--;
- NEEDBITS((unsigned)bb) /* get coded literal */
- if ((e = (t = tb + ((~(unsigned)b) & mb))->e) > 16)
- do {
- if (e == 99)
- return 1;
- DUMPBITS(t->b)
- e -= 16;
- NEEDBITS(e)
- } while ((e = (t = t->v.t + ((~(unsigned)b) & mask_bits[e]))->e) > 16);
- DUMPBITS(t->b)
- redirSlide[w++] = (uch)t->v.n;
- if (w == wsize)
- {
- flush(__G__ redirSlide, (ulg)w, 0);
- w = u = 0;
- }
- }
- else /* else distance/length */
- {
- DUMPBITS(1)
- NEEDBITS(6) /* get distance low bits */
- d = (unsigned)b & 0x3f;
- DUMPBITS(6)
- NEEDBITS((unsigned)bd) /* get coded distance high bits */
- if ((e = (t = td + ((~(unsigned)b) & md))->e) > 16)
- do {
- if (e == 99)
- return 1;
- DUMPBITS(t->b)
- e -= 16;
- NEEDBITS(e)
- } while ((e = (t = t->v.t + ((~(unsigned)b) & mask_bits[e]))->e) > 16);
- DUMPBITS(t->b)
- d = w - d - t->v.n; /* construct offset */
- NEEDBITS((unsigned)bl) /* get coded length */
- if ((e = (t = tl + ((~(unsigned)b) & ml))->e) > 16)
- do {
- if (e == 99)
- return 1;
- DUMPBITS(t->b)
- e -= 16;
- NEEDBITS(e)
- } while ((e = (t = t->v.t + ((~(unsigned)b) & mask_bits[e]))->e) > 16);
- DUMPBITS(t->b)
- n = t->v.n;
- if (e) /* get length extra bits */
- {
- NEEDBITS(8)
- n += (unsigned)b & 0xff;
- DUMPBITS(8)
- }
-
- /* do the copy */
- s -= n;
- do {
-#if (defined(DLL) && !defined(NO_SLIDE_REDIR))
- if (G.redirect_slide) {
- /* &= w/ wsize not needed and wrong if redirect */
- if (d >= wsize)
- return 1;
- n -= (e = (e = wsize - (d > w ? d : w)) > n ? n : e);
- } else
-#endif
- n -= (e = (e = wsize - ((d &= wsize-1) > w ? d : w)) > n ? n : e);
- if (u && w <= d)
- {
- memzero(redirSlide + w, e);
- w += e;
- d += e;
- }
- else
-#ifndef NOMEMCPY
- if (w - d >= e) /* (this test assumes unsigned comparison) */
- {
- memcpy(redirSlide + w, redirSlide + d, e);
- w += e;
- d += e;
- }
- else /* do it slow to avoid memcpy() overlap */
-#endif /* !NOMEMCPY */
- do {
- redirSlide[w++] = redirSlide[d++];
- } while (--e);
- if (w == wsize)
- {
- flush(__G__ redirSlide, (ulg)w, 0);
- w = u = 0;
- }
- } while (n);
- }
- }
-
- /* flush out redirSlide */
- flush(__G__ redirSlide, (ulg)w, 0);
- if (G.csize + G.incnt + (k >> 3)) /* should have read csize bytes, but */
- { /* sometimes read one too many: k>>3 compensates */
- G.used_csize = G.lrec.csize - G.csize - G.incnt - (k >> 3);
- return 5;
- }
- return 0;
-}
-
-
-
-static int explode_nolit8(__G__ tl, td, bl, bd)
- __GDEF
-struct huft *tl, *td; /* length and distance decoder tables */
-int bl, bd; /* number of bits decoded by tl[] and td[] */
-/* Decompress the imploded data using uncoded literals and an 8K sliding
- window. */
-{
- long s; /* bytes to decompress */
- register unsigned e; /* table entry flag/number of extra bits */
- unsigned n, d; /* length and index for copy */
- unsigned w; /* current window position */
- struct huft *t; /* pointer to table entry */
- unsigned ml, md; /* masks for bl and bd bits */
- register ulg b; /* bit buffer */
- register unsigned k; /* number of bits in bit buffer */
- unsigned u; /* true if unflushed */
-
-
- /* explode the coded data */
- b = k = w = 0; /* initialize bit buffer, window */
- u = 1; /* buffer unflushed */
- ml = mask_bits[bl]; /* precompute masks for speed */
- md = mask_bits[bd];
- s = G.ucsize;
- while (s > 0) /* do until ucsize bytes uncompressed */
- {
- NEEDBITS(1)
- if (b & 1) /* then literal--get eight bits */
- {
- DUMPBITS(1)
- s--;
- NEEDBITS(8)
- redirSlide[w++] = (uch)b;
- if (w == wsize)
- {
- flush(__G__ redirSlide, (ulg)w, 0);
- w = u = 0;
- }
- DUMPBITS(8)
- }
- else /* else distance/length */
- {
- DUMPBITS(1)
- NEEDBITS(7) /* get distance low bits */
- d = (unsigned)b & 0x7f;
- DUMPBITS(7)
- NEEDBITS((unsigned)bd) /* get coded distance high bits */
- if ((e = (t = td + ((~(unsigned)b) & md))->e) > 16)
- do {
- if (e == 99)
- return 1;
- DUMPBITS(t->b)
- e -= 16;
- NEEDBITS(e)
- } while ((e = (t = t->v.t + ((~(unsigned)b) & mask_bits[e]))->e) > 16);
- DUMPBITS(t->b)
- d = w - d - t->v.n; /* construct offset */
- NEEDBITS((unsigned)bl) /* get coded length */
- if ((e = (t = tl + ((~(unsigned)b) & ml))->e) > 16)
- do {
- if (e == 99)
- return 1;
- DUMPBITS(t->b)
- e -= 16;
- NEEDBITS(e)
- } while ((e = (t = t->v.t + ((~(unsigned)b) & mask_bits[e]))->e) > 16);
- DUMPBITS(t->b)
- n = t->v.n;
- if (e) /* get length extra bits */
- {
- NEEDBITS(8)
- n += (unsigned)b & 0xff;
- DUMPBITS(8)
- }
-
- /* do the copy */
- s -= n;
- do {
-#if (defined(DLL) && !defined(NO_SLIDE_REDIR))
- if (G.redirect_slide) {
- /* &= w/ wsize not needed and wrong if redirect */
- if (d >= wsize)
- return 1;
- n -= (e = (e = wsize - (d > w ? d : w)) > n ? n : e);
- } else
-#endif
- n -= (e = (e = wsize - ((d &= wsize-1) > w ? d : w)) > n ? n : e);
- if (u && w <= d)
- {
- memzero(redirSlide + w, e);
- w += e;
- d += e;
- }
- else
-#ifndef NOMEMCPY
- if (w - d >= e) /* (this test assumes unsigned comparison) */
- {
- memcpy(redirSlide + w, redirSlide + d, e);
- w += e;
- d += e;
- }
- else /* do it slow to avoid memcpy() overlap */
-#endif /* !NOMEMCPY */
- do {
- redirSlide[w++] = redirSlide[d++];
- } while (--e);
- if (w == wsize)
- {
- flush(__G__ redirSlide, (ulg)w, 0);
- w = u = 0;
- }
- } while (n);
- }
- }
-
- /* flush out redirSlide */
- flush(__G__ redirSlide, (ulg)w, 0);
- if (G.csize + G.incnt + (k >> 3)) /* should have read csize bytes, but */
- { /* sometimes read one too many: k>>3 compensates */
- G.used_csize = G.lrec.csize - G.csize - G.incnt - (k >> 3);
- return 5;
- }
- return 0;
-}
-
-
-
-static int explode_nolit4(__G__ tl, td, bl, bd)
- __GDEF
-struct huft *tl, *td; /* length and distance decoder tables */
-int bl, bd; /* number of bits decoded by tl[] and td[] */
-/* Decompress the imploded data using uncoded literals and a 4K sliding
- window. */
-{
- long s; /* bytes to decompress */
- register unsigned e; /* table entry flag/number of extra bits */
- unsigned n, d; /* length and index for copy */
- unsigned w; /* current window position */
- struct huft *t; /* pointer to table entry */
- unsigned ml, md; /* masks for bl and bd bits */
- register ulg b; /* bit buffer */
- register unsigned k; /* number of bits in bit buffer */
- unsigned u; /* true if unflushed */
-
-
- /* explode the coded data */
- b = k = w = 0; /* initialize bit buffer, window */
- u = 1; /* buffer unflushed */
- ml = mask_bits[bl]; /* precompute masks for speed */
- md = mask_bits[bd];
- s = G.ucsize;
- while (s > 0) /* do until ucsize bytes uncompressed */
- {
- NEEDBITS(1)
- if (b & 1) /* then literal--get eight bits */
- {
- DUMPBITS(1)
- s--;
- NEEDBITS(8)
- redirSlide[w++] = (uch)b;
- if (w == wsize)
- {
- flush(__G__ redirSlide, (ulg)w, 0);
- w = u = 0;
- }
- DUMPBITS(8)
- }
- else /* else distance/length */
- {
- DUMPBITS(1)
- NEEDBITS(6) /* get distance low bits */
- d = (unsigned)b & 0x3f;
- DUMPBITS(6)
- NEEDBITS((unsigned)bd) /* get coded distance high bits */
- if ((e = (t = td + ((~(unsigned)b) & md))->e) > 16)
- do {
- if (e == 99)
- return 1;
- DUMPBITS(t->b)
- e -= 16;
- NEEDBITS(e)
- } while ((e = (t = t->v.t + ((~(unsigned)b) & mask_bits[e]))->e) > 16);
- DUMPBITS(t->b)
- d = w - d - t->v.n; /* construct offset */
- NEEDBITS((unsigned)bl) /* get coded length */
- if ((e = (t = tl + ((~(unsigned)b) & ml))->e) > 16)
- do {
- if (e == 99)
- return 1;
- DUMPBITS(t->b)
- e -= 16;
- NEEDBITS(e)
- } while ((e = (t = t->v.t + ((~(unsigned)b) & mask_bits[e]))->e) > 16);
- DUMPBITS(t->b)
- n = t->v.n;
- if (e) /* get length extra bits */
- {
- NEEDBITS(8)
- n += (unsigned)b & 0xff;
- DUMPBITS(8)
- }
-
- /* do the copy */
- s -= n;
- do {
-#if (defined(DLL) && !defined(NO_SLIDE_REDIR))
- if (G.redirect_slide) {
- /* &= w/ wsize not needed and wrong if redirect */
- if (d >= wsize)
- return 1;
- n -= (e = (e = wsize - (d > w ? d : w)) > n ? n : e);
- } else
-#endif
- n -= (e = (e = wsize - ((d &= wsize-1) > w ? d : w)) > n ? n : e);
- if (u && w <= d)
- {
- memzero(redirSlide + w, e);
- w += e;
- d += e;
- }
- else
-#ifndef NOMEMCPY
- if (w - d >= e) /* (this test assumes unsigned comparison) */
- {
- memcpy(redirSlide + w, redirSlide + d, e);
- w += e;
- d += e;
- }
- else /* do it slow to avoid memcpy() overlap */
-#endif /* !NOMEMCPY */
- do {
- redirSlide[w++] = redirSlide[d++];
- } while (--e);
- if (w == wsize)
- {
- flush(__G__ redirSlide, (ulg)w, 0);
- w = u = 0;
- }
- } while (n);
- }
- }
-
- /* flush out redirSlide */
- flush(__G__ redirSlide, (ulg)w, 0);
- if (G.csize + G.incnt + (k >> 3)) /* should have read csize bytes, but */
- { /* sometimes read one too many: k>>3 compensates */
- G.used_csize = G.lrec.csize - G.csize - G.incnt - (k >> 3);
- return 5;
- }
- return 0;
-}
-
-
-
-int explode(__G)
- __GDEF
-/* Explode an imploded compressed stream. Based on the general purpose
- bit flag, decide on coded or uncoded literals, and an 8K or 4K sliding
- window. Construct the literal (if any), length, and distance codes and
- the tables needed to decode them (using huft_build() from inflate.c),
- and call the appropriate routine for the type of data in the remainder
- of the stream. The four routines are nearly identical, differing only
- in whether the literal is decoded or simply read in, and in how many
- bits are read in, uncoded, for the low distance bits. */
-{
- unsigned r; /* return codes */
- struct huft *tb; /* literal code table */
- struct huft *tl; /* length code table */
- struct huft *td; /* distance code table */
- int bb; /* bits for tb */
- int bl; /* bits for tl */
- int bd; /* bits for td */
- unsigned l[256]; /* bit lengths for codes */
-
-#if (defined(DLL) && !defined(NO_SLIDE_REDIR))
- if (G.redirect_slide)
- wsize = G.redirect_size, redirSlide = G.redirect_buffer;
- else
- wsize = WSIZE, redirSlide = slide;
-#endif
-
- /* Tune base table sizes. Note: I thought that to truly optimize speed,
- I would have to select different bl, bd, and bb values for different
- compressed file sizes. I was surprised to find out that the values of
- 7, 7, and 9 worked best over a very wide range of sizes, except that
- bd = 8 worked marginally better for large compressed sizes. */
- bl = 7;
- bd = (G.csize + G.incnt) > 200000L ? 8 : 7;
-
-
- /* With literal tree--minimum match length is 3 */
-#ifdef DEBUG
- G.hufts = 0; /* initialize huft's malloc'ed */
-#endif
- if (G.lrec.general_purpose_bit_flag & 4)
- {
- bb = 9; /* base table size for literals */
- if ((r = get_tree(__G__ l, 256)) != 0)
- return (int)r;
- if ((r = huft_build(__G__ l, 256, 256, NULL, NULL, &tb, &bb)) != 0)
- {
- if (r == 1)
- huft_free(tb);
- return (int)r;
- }
- if ((r = get_tree(__G__ l, 64)) != 0)
- return (int)r;
- if ((r = huft_build(__G__ l, 64, 0, cplen3, extra, &tl, &bl)) != 0)
- {
- if (r == 1)
- huft_free(tl);
- huft_free(tb);
- return (int)r;
- }
- if ((r = get_tree(__G__ l, 64)) != 0)
- return (int)r;
- if (G.lrec.general_purpose_bit_flag & 2) /* true if 8K */
- {
- if ((r = huft_build(__G__ l, 64, 0, cpdist8, extra, &td, &bd)) != 0)
- {
- if (r == 1)
- huft_free(td);
- huft_free(tl);
- huft_free(tb);
- return (int)r;
- }
- r = explode_lit8(__G__ tb, tl, td, bb, bl, bd);
- }
- else /* else 4K */
- {
- if ((r = huft_build(__G__ l, 64, 0, cpdist4, extra, &td, &bd)) != 0)
- {
- if (r == 1)
- huft_free(td);
- huft_free(tl);
- huft_free(tb);
- return (int)r;
- }
- r = explode_lit4(__G__ tb, tl, td, bb, bl, bd);
- }
- huft_free(td);
- huft_free(tl);
- huft_free(tb);
- }
- else
-
-
- /* No literal tree--minimum match length is 2 */
- {
- if ((r = get_tree(__G__ l, 64)) != 0)
- return (int)r;
- if ((r = huft_build(__G__ l, 64, 0, cplen2, extra, &tl, &bl)) != 0)
- {
- if (r == 1)
- huft_free(tl);
- return (int)r;
- }
- if ((r = get_tree(__G__ l, 64)) != 0)
- return (int)r;
- if (G.lrec.general_purpose_bit_flag & 2) /* true if 8K */
- {
- if ((r = huft_build(__G__ l, 64, 0, cpdist8, extra, &td, &bd)) != 0)
- {
- if (r == 1)
- huft_free(td);
- huft_free(tl);
- return (int)r;
- }
- r = explode_nolit8(__G__ tl, td, bl, bd);
- }
- else /* else 4K */
- {
- if ((r = huft_build(__G__ l, 64, 0, cpdist4, extra, &td, &bd)) != 0)
- {
- if (r == 1)
- huft_free(td);
- huft_free(tl);
- return (int)r;
- }
- r = explode_nolit4(__G__ tl, td, bl, bd);
- }
- huft_free(td);
- huft_free(tl);
- }
- Trace((stderr, "<%u > ", G.hufts));
- return (int)r;
-}
-
-/* so explode.c and inflate.c can be compiled together into one object: */
-#undef NEXTBYTE
-#undef NEEDBITS
-#undef DUMPBITS
projects / wxWidgets.git / blobdiff