From 7b67103941cf57732abad165c09e63301bf2ef4a Mon Sep 17 00:00:00 2001 From: Wayne Davison Date: Thu, 28 Jul 2005 18:00:04 +0000 Subject: A fix for zlib 1.1.4 that was supplied by Tim Yamin. --- zlib/inftrees.c | 719 +++++++++++++++++++++++++++++++++----------------------- 1 file changed, 422 insertions(+), 297 deletions(-) diff --git a/zlib/inftrees.c b/zlib/inftrees.c index 8a9c13ff..28015112 100644 --- a/zlib/inftrees.c +++ b/zlib/inftrees.c @@ -1,329 +1,454 @@ /* inftrees.c -- generate Huffman trees for efficient decoding - * Copyright (C) 1995-2005 Mark Adler - * For conditions of distribution and use, see copyright notice in zlib.h + * Copyright (C) 1995-2002 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h */ #include "zutil.h" #include "inftrees.h" -#define MAXBITS 15 +#if !defined(BUILDFIXED) && !defined(STDC) +# define BUILDFIXED /* non ANSI compilers may not accept inffixed.h */ +#endif const char inflate_copyright[] = - " inflate 1.2.3 Copyright 1995-2005 Mark Adler "; + " inflate 1.1.4 Copyright 1995-2002 Mark Adler "; /* If you use the zlib library in a product, an acknowledgment is welcome in the documentation of your product. If for some reason you cannot include such an acknowledgment, I would appreciate that you keep this copyright string in the executable of your product. */ - -/* - Build a set of tables to decode the provided canonical Huffman code. - The code lengths are lens[0..codes-1]. The result starts at *table, - whose indices are 0..2^bits-1. work is a writable array of at least - lens shorts, which is used as a work area. type is the type of code - to be generated, CODES, LENS, or DISTS. On return, zero is success, - -1 is an invalid code, and +1 means that ENOUGH isn't enough. table - on return points to the next available entry's address. bits is the - requested root table index bits, and on return it is the actual root - table index bits. It will differ if the request is greater than the - longest code or if it is less than the shortest code. - */ -int inflate_table(type, lens, codes, table, bits, work) -codetype type; -unsigned short FAR *lens; -unsigned codes; -code FAR * FAR *table; -unsigned FAR *bits; -unsigned short FAR *work; -{ - unsigned len; /* a code's length in bits */ - unsigned sym; /* index of code symbols */ - unsigned min, max; /* minimum and maximum code lengths */ - unsigned root; /* number of index bits for root table */ - unsigned curr; /* number of index bits for current table */ - unsigned drop; /* code bits to drop for sub-table */ - int left; /* number of prefix codes available */ - unsigned used; /* code entries in table used */ - unsigned huff; /* Huffman code */ - unsigned incr; /* for incrementing code, index */ - unsigned fill; /* index for replicating entries */ - unsigned low; /* low bits for current root entry */ - unsigned mask; /* mask for low root bits */ - code this; /* table entry for duplication */ - code FAR *next; /* next available space in table */ - const unsigned short FAR *base; /* base value table to use */ - const unsigned short FAR *extra; /* extra bits table to use */ - int end; /* use base and extra for symbol > end */ - unsigned short count[MAXBITS+1]; /* number of codes of each length */ - unsigned short offs[MAXBITS+1]; /* offsets in table for each length */ - static const unsigned short lbase[31] = { /* Length codes 257..285 base */ +struct internal_state {int dummy;}; /* for buggy compilers */ + +/* simplify the use of the inflate_huft type with some defines */ +#define exop word.what.Exop +#define bits word.what.Bits + + +local int huft_build OF(( + uIntf *, /* code lengths in bits */ + uInt, /* number of codes */ + uInt, /* number of "simple" codes */ + const uIntf *, /* list of base values for non-simple codes */ + const uIntf *, /* list of extra bits for non-simple codes */ + inflate_huft * FAR*,/* result: starting table */ + uIntf *, /* maximum lookup bits (returns actual) */ + inflate_huft *, /* space for trees */ + uInt *, /* hufts used in space */ + uIntf * )); /* space for values */ + +/* Tables for deflate from PKZIP's appnote.txt. */ +local const uInt cplens[31] = { /* Copy lengths for literal codes 257..285 */ 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0}; - static const unsigned short lext[31] = { /* Length codes 257..285 extra */ - 16, 16, 16, 16, 16, 16, 16, 16, 17, 17, 17, 17, 18, 18, 18, 18, - 19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 16, 201, 196}; - static const unsigned short dbase[32] = { /* Distance codes 0..29 base */ + /* see note #13 above about 258 */ +local const uInt cplext[31] = { /* Extra bits for literal codes 257..285 */ + 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, + 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 112, 112}; /* 112==invalid */ +local const uInt cpdist[30] = { /* Copy offsets for distance codes 0..29 */ 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145, - 8193, 12289, 16385, 24577, 0, 0}; - static const unsigned short dext[32] = { /* Distance codes 0..29 extra */ - 16, 16, 16, 16, 17, 17, 18, 18, 19, 19, 20, 20, 21, 21, 22, 22, - 23, 23, 24, 24, 25, 25, 26, 26, 27, 27, - 28, 28, 29, 29, 64, 64}; - - /* - Process a set of code lengths to create a canonical Huffman code. The - code lengths are lens[0..codes-1]. Each length corresponds to the - symbols 0..codes-1. The Huffman code is generated by first sorting the - symbols by length from short to long, and retaining the symbol order - for codes with equal lengths. Then the code starts with all zero bits - for the first code of the shortest length, and the codes are integer - increments for the same length, and zeros are appended as the length - increases. For the deflate format, these bits are stored backwards - from their more natural integer increment ordering, and so when the - decoding tables are built in the large loop below, the integer codes - are incremented backwards. - - This routine assumes, but does not check, that all of the entries in - lens[] are in the range 0..MAXBITS. The caller must assure this. - 1..MAXBITS is interpreted as that code length. zero means that that - symbol does not occur in this code. - - The codes are sorted by computing a count of codes for each length, - creating from that a table of starting indices for each length in the - sorted table, and then entering the symbols in order in the sorted - table. The sorted table is work[], with that space being provided by - the caller. - - The length counts are used for other purposes as well, i.e. finding - the minimum and maximum length codes, determining if there are any - codes at all, checking for a valid set of lengths, and looking ahead - at length counts to determine sub-table sizes when building the - decoding tables. - */ - - /* accumulate lengths for codes (assumes lens[] all in 0..MAXBITS) */ - for (len = 0; len <= MAXBITS; len++) - count[len] = 0; - for (sym = 0; sym < codes; sym++) - count[lens[sym]]++; - - /* bound code lengths, force root to be within code lengths */ - root = *bits; - for (max = MAXBITS; max >= 1; max--) - if (count[max] != 0) break; - if (root > max) root = max; - if (max == 0) { /* no symbols to code at all */ - this.op = (unsigned char)64; /* invalid code marker */ - this.bits = (unsigned char)1; - this.val = (unsigned short)0; - *(*table)++ = this; /* make a table to force an error */ - *(*table)++ = this; - *bits = 1; - return 0; /* no symbols, but wait for decoding to report error */ - } - for (min = 1; min <= MAXBITS; min++) - if (count[min] != 0) break; - if (root < min) root = min; - - /* check for an over-subscribed or incomplete set of lengths */ - left = 1; - for (len = 1; len <= MAXBITS; len++) { - left <<= 1; - left -= count[len]; - if (left < 0) return -1; /* over-subscribed */ - } - if (left > 0 && (type == CODES || max != 1)) - return -1; /* incomplete set */ - - /* generate offsets into symbol table for each length for sorting */ - offs[1] = 0; - for (len = 1; len < MAXBITS; len++) - offs[len + 1] = offs[len] + count[len]; - - /* sort symbols by length, by symbol order within each length */ - for (sym = 0; sym < codes; sym++) - if (lens[sym] != 0) work[offs[lens[sym]]++] = (unsigned short)sym; - - /* - Create and fill in decoding tables. In this loop, the table being - filled is at next and has curr index bits. The code being used is huff - with length len. That code is converted to an index by dropping drop - bits off of the bottom. For codes where len is less than drop + curr, - those top drop + curr - len bits are incremented through all values to - fill the table with replicated entries. - - root is the number of index bits for the root table. When len exceeds - root, sub-tables are created pointed to by the root entry with an index - of the low root bits of huff. This is saved in low to check for when a - new sub-table should be started. drop is zero when the root table is - being filled, and drop is root when sub-tables are being filled. - - When a new sub-table is needed, it is necessary to look ahead in the - code lengths to determine what size sub-table is needed. The length - counts are used for this, and so count[] is decremented as codes are - entered in the tables. - - used keeps track of how many table entries have been allocated from the - provided *table space. It is checked when a LENS table is being made - against the space in *table, ENOUGH, minus the maximum space needed by - the worst case distance code, MAXD. This should never happen, but the - sufficiency of ENOUGH has not been proven exhaustively, hence the check. - This assumes that when type == LENS, bits == 9. - - sym increments through all symbols, and the loop terminates when - all codes of length max, i.e. all codes, have been processed. This - routine permits incomplete codes, so another loop after this one fills - in the rest of the decoding tables with invalid code markers. - */ - - /* set up for code type */ - switch (type) { - case CODES: - base = extra = work; /* dummy value--not used */ - end = 19; - break; - case LENS: - base = lbase; - base -= 257; - extra = lext; - extra -= 257; - end = 256; - break; - default: /* DISTS */ - base = dbase; - extra = dext; - end = -1; - } + 8193, 12289, 16385, 24577}; +local const uInt cpdext[30] = { /* Extra bits for distance codes */ + 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, + 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, + 12, 12, 13, 13}; - /* initialize state for loop */ - huff = 0; /* starting code */ - sym = 0; /* starting code symbol */ - len = min; /* starting code length */ - next = *table; /* current table to fill in */ - curr = root; /* current table index bits */ - drop = 0; /* current bits to drop from code for index */ - low = (unsigned)(-1); /* trigger new sub-table when len > root */ - used = 1U << root; /* use root table entries */ - mask = used - 1; /* mask for comparing low */ - - /* check available table space */ - if (type == LENS && used >= ENOUGH - MAXD) - return 1; - - /* process all codes and make table entries */ - for (;;) { - /* create table entry */ - this.bits = (unsigned char)(len - drop); - if ((int)(work[sym]) < end) { - this.op = (unsigned char)0; - this.val = work[sym]; - } - else if ((int)(work[sym]) > end) { - this.op = (unsigned char)(extra[work[sym]]); - this.val = base[work[sym]]; - } - else { - this.op = (unsigned char)(32 + 64); /* end of block */ - this.val = 0; - } +/* + Huffman code decoding is performed using a multi-level table lookup. + The fastest way to decode is to simply build a lookup table whose + size is determined by the longest code. However, the time it takes + to build this table can also be a factor if the data being decoded + is not very long. The most common codes are necessarily the + shortest codes, so those codes dominate the decoding time, and hence + the speed. The idea is you can have a shorter table that decodes the + shorter, more probable codes, and then point to subsidiary tables for + the longer codes. The time it costs to decode the longer codes is + then traded against the time it takes to make longer tables. + + This results of this trade are in the variables lbits and dbits + below. lbits is the number of bits the first level table for literal/ + length codes can decode in one step, and dbits is the same thing for + the distance codes. Subsequent tables are also less than or equal to + those sizes. These values may be adjusted either when all of the + codes are shorter than that, in which case the longest code length in + bits is used, or when the shortest code is *longer* than the requested + table size, in which case the length of the shortest code in bits is + used. + + There are two different values for the two tables, since they code a + different number of possibilities each. The literal/length table + codes 286 possible values, or in a flat code, a little over eight + bits. The distance table codes 30 possible values, or a little less + than five bits, flat. The optimum values for speed end up being + about one bit more than those, so lbits is 8+1 and dbits is 5+1. + The optimum values may differ though from machine to machine, and + possibly even between compilers. Your mileage may vary. + */ - /* replicate for those indices with low len bits equal to huff */ - incr = 1U << (len - drop); - fill = 1U << curr; - min = fill; /* save offset to next table */ - do { - fill -= incr; - next[(huff >> drop) + fill] = this; - } while (fill != 0); - - /* backwards increment the len-bit code huff */ - incr = 1U << (len - 1); - while (huff & incr) - incr >>= 1; - if (incr != 0) { - huff &= incr - 1; - huff += incr; + +/* If BMAX needs to be larger than 16, then h and x[] should be uLong. */ +#define BMAX 15 /* maximum bit length of any code */ + +local int huft_build(b, n, s, d, e, t, m, hp, hn, v) +uIntf *b; /* code lengths in bits (all assumed <= BMAX) */ +uInt n; /* number of codes (assumed <= 288) */ +uInt s; /* number of simple-valued codes (0..s-1) */ +const uIntf *d; /* list of base values for non-simple codes */ +const uIntf *e; /* list of extra bits for non-simple codes */ +inflate_huft * FAR *t; /* result: starting table */ +uIntf *m; /* maximum lookup bits, returns actual */ +inflate_huft *hp; /* space for trees */ +uInt *hn; /* hufts used in space */ +uIntf *v; /* working area: values in order of bit length */ +/* Given a list of code lengths and a maximum table size, make a set of + tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR + if the given code set is incomplete (the tables are still built in this + case), or Z_DATA_ERROR if the input is invalid. */ +{ + + uInt a; /* counter for codes of length k */ + uInt c[BMAX+1]; /* bit length count table */ + uInt f; /* i repeats in table every f entries */ + int g; /* maximum code length */ + int h; /* table level */ + register uInt i; /* counter, current code */ + register uInt j; /* counter */ + register int k; /* number of bits in current code */ + int l; /* bits per table (returned in m) */ + uInt mask; /* (1 << w) - 1, to avoid cc -O bug on HP */ + register uIntf *p; /* pointer into c[], b[], or v[] */ + inflate_huft *q; /* points to current table */ + struct inflate_huft_s r; /* table entry for structure assignment */ + inflate_huft *u[BMAX]; /* table stack */ + register int w; /* bits before this table == (l * h) */ + uInt x[BMAX+1]; /* bit offsets, then code stack */ + uIntf *xp; /* pointer into x */ + int y; /* number of dummy codes added */ + uInt z; /* number of entries in current table */ + + + /* Generate counts for each bit length */ + p = c; +#define C0 *p++ = 0; +#define C2 C0 C0 C0 C0 +#define C4 C2 C2 C2 C2 + C4 /* clear c[]--assume BMAX+1 is 16 */ + p = b; i = n; + do { + c[*p++]++; /* assume all entries <= BMAX */ + } while (--i); + if (c[0] == n) /* null input--all zero length codes */ + { + *t = (inflate_huft *)Z_NULL; + *m = 0; + return Z_DATA_ERROR; + } + + + /* Find minimum and maximum length, bound *m by those */ + l = *m; + for (j = 1; j <= BMAX; j++) + if (c[j]) + break; + k = j; /* minimum code length */ + if ((uInt)l < j) + l = j; + for (i = BMAX; i; i--) + if (c[i]) + break; + g = i; /* maximum code length */ + if ((uInt)l > i) + l = i; + *m = l; + + + /* Adjust last length count to fill out codes, if needed */ + for (y = 1 << j; j < i; j++, y <<= 1) + if ((y -= c[j]) < 0) + return Z_DATA_ERROR; + if ((y -= c[i]) < 0) + return Z_DATA_ERROR; + c[i] += y; + + + /* Generate starting offsets into the value table for each length */ + x[1] = j = 0; + p = c + 1; xp = x + 2; + while (--i) { /* note that i == g from above */ + *xp++ = (j += *p++); + } + + + /* Make a table of values in order of bit lengths */ + p = b; i = 0; + do { + if ((j = *p++) != 0) + v[x[j]++] = i; + } while (++i < n); + n = x[g]; /* set n to length of v */ + + + /* Generate the Huffman codes and for each, make the table entries */ + x[0] = i = 0; /* first Huffman code is zero */ + p = v; /* grab values in bit order */ + h = -1; /* no tables yet--level -1 */ + w = -l; /* bits decoded == (l * h) */ + u[0] = (inflate_huft *)Z_NULL; /* just to keep compilers happy */ + q = (inflate_huft *)Z_NULL; /* ditto */ + z = 0; /* ditto */ + + /* go through the bit lengths (k already is bits in shortest code) */ + for (; k <= g; k++) + { + a = c[k]; + while (a--) + { + /* here i is the Huffman code of length k bits for value *p */ + /* make tables up to required level */ + while (k > w + l) + { + h++; + w += l; /* previous table always l bits */ + + /* compute minimum size table less than or equal to l bits */ + z = g - w; + z = z > (uInt)l ? (uInt)l : z; /* table size upper limit */ + if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */ + { /* too few codes for k-w bit table */ + f -= a + 1; /* deduct codes from patterns left */ + xp = c + k; + if (j < z) + while (++j < z) /* try smaller tables up to z bits */ + { + if ((f <<= 1) <= *++xp) + break; /* enough codes to use up j bits */ + f -= *xp; /* else deduct codes from patterns */ + } + } + z = 1 << j; /* table entries for j-bit table */ + + /* allocate new table */ + if (*hn + z > MANY) /* (note: doesn't matter for fixed) */ + return Z_DATA_ERROR; /* overflow of MANY */ + u[h] = q = hp + *hn; + *hn += z; + + /* connect to last table, if there is one */ + if (h) + { + x[h] = i; /* save pattern for backing up */ + r.bits = (Byte)l; /* bits to dump before this table */ + r.exop = (Byte)j; /* bits in this table */ + j = i >> (w - l); + r.base = (uInt)(q - u[h-1] - j); /* offset to this table */ + u[h-1][j] = r; /* connect to last table */ } else - huff = 0; + *t = q; /* first table is returned result */ + } + + /* set up table entry in r */ + r.bits = (Byte)(k - w); + if (p >= v + n) + r.exop = 128 + 64; /* out of values--invalid code */ + else if (*p < s) + { + r.exop = (Byte)(*p < 256 ? 0 : 32 + 64); /* 256 is end-of-block */ + r.base = *p++; /* simple code is just the value */ + } + else + { + r.exop = (Byte)(e[*p - s] + 16 + 64);/* non-simple--look up in lists */ + r.base = d[*p++ - s]; + } + + /* fill code-like entries with r */ + f = 1 << (k - w); + for (j = i >> w; j < z; j += f) + q[j] = r; + + /* backwards increment the k-bit code i */ + for (j = 1 << (k - 1); i & j; j >>= 1) + i ^= j; + i ^= j; + + /* backup over finished tables */ + mask = (1 << w) - 1; /* needed on HP, cc -O bug */ + while ((i & mask) != x[h]) + { + h--; /* don't need to update q */ + w -= l; + mask = (1 << w) - 1; + } + } + } - /* go to next symbol, update count, len */ - sym++; - if (--(count[len]) == 0) { - if (len == max) break; - len = lens[work[sym]]; - } - /* create new sub-table if needed */ - if (len > root && (huff & mask) != low) { - /* if first time, transition to sub-tables */ - if (drop == 0) - drop = root; - - /* increment past last table */ - next += min; /* here min is 1 << curr */ - - /* determine length of next table */ - curr = len - drop; - left = (int)(1 << curr); - while (curr + drop < max) { - left -= count[curr + drop]; - if (left <= 0) break; - curr++; - left <<= 1; - } + /* Return Z_BUF_ERROR if we were given an incomplete table */ + return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK; +} - /* check for enough space */ - used += 1U << curr; - if (type == LENS && used >= ENOUGH - MAXD) - return 1; - /* point entry in root table to sub-table */ - low = huff & mask; - (*table)[low].op = (unsigned char)curr; - (*table)[low].bits = (unsigned char)root; - (*table)[low].val = (unsigned short)(next - *table); - } - } +int inflate_trees_bits(c, bb, tb, hp, z) +uIntf *c; /* 19 code lengths */ +uIntf *bb; /* bits tree desired/actual depth */ +inflate_huft * FAR *tb; /* bits tree result */ +inflate_huft *hp; /* space for trees */ +z_streamp z; /* for messages */ +{ + int r; + uInt hn = 0; /* hufts used in space */ + uIntf *v; /* work area for huft_build */ + + if ((v = (uIntf*)ZALLOC(z, 19, sizeof(uInt))) == Z_NULL) + return Z_MEM_ERROR; + r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL, + tb, bb, hp, &hn, v); + if (r == Z_DATA_ERROR) + z->msg = (char*)"oversubscribed dynamic bit lengths tree"; + else if (r == Z_BUF_ERROR || *bb == 0) + { + z->msg = (char*)"incomplete dynamic bit lengths tree"; + r = Z_DATA_ERROR; + } + ZFREE(z, v); + return r; +} - /* - Fill in rest of table for incomplete codes. This loop is similar to the - loop above in incrementing huff for table indices. It is assumed that - len is equal to curr + drop, so there is no loop needed to increment - through high index bits. When the current sub-table is filled, the loop - drops back to the root table to fill in any remaining entries there. - */ - this.op = (unsigned char)64; /* invalid code marker */ - this.bits = (unsigned char)(len - drop); - this.val = (unsigned short)0; - while (huff != 0) { - /* when done with sub-table, drop back to root table */ - if (drop != 0 && (huff & mask) != low) { - drop = 0; - len = root; - next = *table; - this.bits = (unsigned char)len; - } - /* put invalid code marker in table */ - next[huff >> drop] = this; +int inflate_trees_dynamic(nl, nd, c, bl, bd, tl, td, hp, z) +uInt nl; /* number of literal/length codes */ +uInt nd; /* number of distance codes */ +uIntf *c; /* that many (total) code lengths */ +uIntf *bl; /* literal desired/actual bit depth */ +uIntf *bd; /* distance desired/actual bit depth */ +inflate_huft * FAR *tl; /* literal/length tree result */ +inflate_huft * FAR *td; /* distance tree result */ +inflate_huft *hp; /* space for trees */ +z_streamp z; /* for messages */ +{ + int r; + uInt hn = 0; /* hufts used in space */ + uIntf *v; /* work area for huft_build */ + + /* allocate work area */ + if ((v = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL) + return Z_MEM_ERROR; + + /* build literal/length tree */ + r = huft_build(c, nl, 257, cplens, cplext, tl, bl, hp, &hn, v); + if (r != Z_OK || *bl == 0) + { + if (r == Z_DATA_ERROR) + z->msg = (char*)"oversubscribed literal/length tree"; + else if (r != Z_MEM_ERROR) + { + z->msg = (char*)"incomplete literal/length tree"; + r = Z_DATA_ERROR; + } + ZFREE(z, v); + return r; + } + + /* build distance tree */ + r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, hp, &hn, v); + if (r != Z_OK || (*bd == 0 && nl > 257)) + { + if (r == Z_DATA_ERROR) + z->msg = (char*)"oversubscribed distance tree"; + else if (r == Z_BUF_ERROR) { +#ifdef PKZIP_BUG_WORKAROUND + r = Z_OK; + } +#else + z->msg = (char*)"incomplete distance tree"; + r = Z_DATA_ERROR; + } + else if (r != Z_MEM_ERROR) + { + z->msg = (char*)"empty distance tree with lengths"; + r = Z_DATA_ERROR; + } + ZFREE(z, v); + return r; +#endif + } + + /* done */ + ZFREE(z, v); + return Z_OK; +} + - /* backwards increment the len-bit code huff */ - incr = 1U << (len - 1); - while (huff & incr) - incr >>= 1; - if (incr != 0) { - huff &= incr - 1; - huff += incr; - } - else - huff = 0; +/* build fixed tables only once--keep them here */ +#ifdef BUILDFIXED +local int fixed_built = 0; +#define FIXEDH 544 /* number of hufts used by fixed tables */ +local inflate_huft fixed_mem[FIXEDH]; +local uInt fixed_bl; +local uInt fixed_bd; +local inflate_huft *fixed_tl; +local inflate_huft *fixed_td; +#else +#include "inffixed.h" +#endif + + +int inflate_trees_fixed(bl, bd, tl, td, z) +uIntf *bl; /* literal desired/actual bit depth */ +uIntf *bd; /* distance desired/actual bit depth */ +inflate_huft * FAR *tl; /* literal/length tree result */ +inflate_huft * FAR *td; /* distance tree result */ +UNUSED(z_streamp z); /* for memory allocation */ +{ +#ifdef BUILDFIXED + /* build fixed tables if not already */ + if (!fixed_built) + { + int k; /* temporary variable */ + uInt f = 0; /* number of hufts used in fixed_mem */ + uIntf *c; /* length list for huft_build */ + uIntf *v; /* work area for huft_build */ + + /* allocate memory */ + if ((c = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL) + return Z_MEM_ERROR; + if ((v = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL) + { + ZFREE(z, c); + return Z_MEM_ERROR; } - /* set return parameters */ - *table += used; - *bits = root; - return 0; + /* literal table */ + for (k = 0; k < 144; k++) + c[k] = 8; + for (; k < 256; k++) + c[k] = 9; + for (; k < 280; k++) + c[k] = 7; + for (; k < 288; k++) + c[k] = 8; + fixed_bl = 9; + huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl, + fixed_mem, &f, v); + + /* distance table */ + for (k = 0; k < 30; k++) + c[k] = 5; + fixed_bd = 5; + huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd, + fixed_mem, &f, v); + + /* done */ + ZFREE(z, v); + ZFREE(z, c); + fixed_built = 1; + } +#endif + *bl = fixed_bl; + *bd = fixed_bd; + *tl = fixed_tl; + *td = fixed_td; + return Z_OK; } -- cgit v1.2.1