diff options
Diffstat (limited to 'toys/pending/gzip.c')
| -rw-r--r-- | toys/pending/gzip.c | 1965 |
1 files changed, 1965 insertions, 0 deletions
diff --git a/toys/pending/gzip.c b/toys/pending/gzip.c new file mode 100644 index 00000000..ada2b323 --- /dev/null +++ b/toys/pending/gzip.c @@ -0,0 +1,1965 @@ +/* gzip.c - deflate and inflate code rolled into a ball. + * + * Copyright 2009 Szabolcs Nagy <nszabolcs@gmail.com> + * + * See http://refspecs.linuxfoundation.org/LSB_4.1.0/LSB-Core-generic/LSB-Core-generic/gzip.html + * And RFCs 1950, 1951, and 1952 + +USE_GZIP(NEWTOY(gzip, "qvcdrgzp", TOYFLAG_USR|TOYFLAG_BIN)) + +config GZIP + bool "gzip" + default n + help + usage: gzip [-qvcdrgzp] FILE + + Transitional gzip, needs work. Combines gzip, zlib, and pkzip. + + -q quiet (default)\n + -v verbose\n + -c compress (default)\n + -d decompress\n + -r raw (default)\n + -g gzip\n + -z zlib\n + -p pkzip\n +*/ + +#define FOR_gzip +#include "toys.h" + +typedef unsigned char uchar; +typedef unsigned short ushort; +typedef unsigned int uint; + +/* deflate and inflate return values */ +enum { + FlateOk = 0, + FlateErr = -1, + FlateIn = -2, + FlateOut = -3 +}; + +typedef struct { + int nin; + int nout; + uchar *in; + uchar *out; + char *err; + void *state; +} FlateStream; + +int deflate(FlateStream *s); +int inflate(FlateStream *s); + +uint adler32(uchar *p, int n, uint adler); +void crc32init(void); +uint crc32(uchar *p, int n, uint crc); + +uint crctab[256]; + +void crc32init(void) { + static const uint poly = 0xedb88320; + int i,j; + + for (i = 0; i < 256; ++i) { + uint crc = i; + + for (j = 0; j < 8; j++) { + if (crc & 1) + crc = (crc >> 1) ^ poly; + else + crc >>= 1; + } + crctab[i] = crc; + } +} + +uint crc32(uchar *p, int n, uint crc) { + uchar *ep = p + n; + + crc ^= 0xffffffff; + while (p < ep) + crc = crctab[(crc & 0xff) ^ *p++] ^ (crc >> 8); + return crc ^ 0xffffffff; +} + +enum { + AdlerBase = 65521, /* largest 16bit prime */ + AdlerN = 5552 /* max iters before 32bit overflow */ +}; + +uint adler32(uchar *p, int n, uint adler) { + uint s1 = adler & 0xffff; + uint s2 = (adler >> 16) & 0xffff; + uchar *ep; + int k; + + for (; n >= 16; n -= k) { + k = n < AdlerN ? n : AdlerN; + k &= ~0xf; + for (ep = p + k; p < ep; p += 16) { + s1 += p[0]; + s2 += s1; + s1 += p[1]; + s2 += s1; + s1 += p[2]; + s2 += s1; + s1 += p[3]; + s2 += s1; + s1 += p[4]; + s2 += s1; + s1 += p[5]; + s2 += s1; + s1 += p[6]; + s2 += s1; + s1 += p[7]; + s2 += s1; + s1 += p[8]; + s2 += s1; + s1 += p[9]; + s2 += s1; + s1 += p[10]; + s2 += s1; + s1 += p[11]; + s2 += s1; + s1 += p[12]; + s2 += s1; + s1 += p[13]; + s2 += s1; + s1 += p[14]; + s2 += s1; + s1 += p[15]; + s2 += s1; + } + s1 %= AdlerBase; + s2 %= AdlerBase; + } + if (n) { + for (ep = p + n; p < ep; p++) { + s1 += p[0]; + s2 += s1; + } + s1 %= AdlerBase; + s2 %= AdlerBase; + } + return (s2 << 16) + s1; +} + +enum { + CodeBits = 16, /* max number of bits in a code + 1 */ + LitlenTableBits = 9, /* litlen code bits used in lookup table */ + DistTableBits = 6, /* dist code bits used in lookup table */ + ClenTableBits = 6, /* clen code bits used in lookup table */ + TableBits = LitlenTableBits, /* log2(lookup table size) */ + Nlit = 256, /* number of lit codes */ + Nlen = 29, /* number of len codes */ + Nlitlen = Nlit+Nlen+3, /* litlen codes + block end + 2 unused */ + Ndist = 30, /* number of distance codes */ + Nclen = 19, /* number of code length codes */ + + EOB = 256, /* end of block symbol */ + MinMatch = 3, /* min match length */ + MaxMatch = 258, /* max match length */ + WinSize = 1 << 15, /* sliding window size */ + + MaxChainLen = 256, /* max length of hash chain */ + HashBits = 13, + HashSize = 1 << HashBits, /* hash table size */ + BigDist = 1 << 12, /* max match distance for short match length */ + MaxDist = WinSize, + BlockSize = 1 << 15, /* TODO */ + SrcSize = 2*WinSize + MaxMatch, + DstSize = BlockSize + MaxMatch + 6, /* worst case compressed block size */ + LzSize = 1 << 13, /* lz buffer size */ + LzGuard = LzSize - 2, + LzLitFlag = 1 << 15 /* marks literal run length in lz buffer */ +}; + +/* states */ +enum { + BlockHead, + UncompressedBlock, + CopyUncompressed, + FixedHuff, + DynamicHuff, + DynamicHuffClen, + DynamicHuffLitlenDist, + DynamicHuffContinue, + DecodeBlock, + DecodeBlockLenBits, + DecodeBlockDist, + DecodeBlockDistBits, + DecodeBlockCopy +}; + +typedef struct { + short len; /* code length */ + ushort sym; /* symbol */ +} Entry; + +/* huffman code tree */ +typedef struct { + Entry table[1 << TableBits]; /* prefix lookup table */ + uint nbits; /* prefix length (table size is 1 << nbits) */ + uint sum; /* full codes in table: sum(count[0..nbits]) */ + ushort count[CodeBits]; /* number of codes with given length */ + ushort symbol[Nlitlen]; /* symbols ordered by code length (lexic.) */ +} Huff; + +typedef struct { + uchar *src; /* input buffer pointer */ + uchar *srcend; + + uint bits; + uint nbits; + + uchar win[WinSize]; /* output window */ + uint pos; /* window pos */ + uint posout; /* used for flushing win */ + + int state; /* decode state */ + int final; /* last block flag */ + char *err; /* TODO: error message */ + + /* for decoding dynamic code trees in inflate() */ + int nlit; + int ndist; + int nclen; /* also used in decode_block() */ + int lenpos; /* also used in decode_block() */ + uchar lens[Nlitlen + Ndist]; + + int fixed; /* fixed code tree flag */ + Huff lhuff; /* dynamic lit/len huffman code tree */ + Huff dhuff; /* dynamic distance huffman code tree */ +} DecodeState; + +/* TODO: globals.. initialization is not thread safe */ +static Huff lhuff; /* fixed lit/len huffman code tree */ +static Huff dhuff; /* fixed distance huffman code tree */ + +/* base offset and extra bits tables */ +static uchar lenbits[Nlen] = { + 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 +}; +static ushort lenbase[Nlen] = { + 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 +}; +static uchar distbits[Ndist] = { + 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 +}; +static ushort distbase[Ndist] = { + 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 +}; + +/* ordering of code lengths */ +static uchar clenorder[Nclen] = { + 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15 +}; + +/* TODO: this or normal inc + reverse() */ +/* increment bitwise reversed n (msb is bit 0, lsb is bit len-1) */ +static uint revinc(uint n, uint len) { + uint i = 1 << (len - 1); + + while (n & i) + i >>= 1; + if (i) { + n &= i - 1; + n |= i; + } else + n = 0; + return n; +} + +/* build huffman code tree from code lengths (each should be < CodeBits) */ +static int build_huff(Huff *huff, uchar *lens, uint n, uint nbits) { + int offs[CodeBits]; + int left; + uint i, c, sum, code, len, min, max; + ushort *count = huff->count; + ushort *symbol = huff->symbol; + Entry *table = huff->table; + Entry entry; + + /* count code lengths */ + for (i = 0; i < CodeBits; i++) + count[i] = 0; + for (i = 0; i < n; i++) + count[lens[i]]++; + if (count[0] == n) { + huff->nbits = table[0].len = 0; + return 0; + } + count[0] = 0; + + /* bound code lengths, force nbits to be within the bounds */ + for (max = CodeBits - 1; max > 0; max--) + if (count[max] != 0) + break; + if (nbits > max) + nbits = max; + for (min = 1; min < CodeBits; min++) + if (count[min] != 0) + break; + if (nbits < min) { + nbits = min; + if (nbits > TableBits) + return -1; + } + huff->nbits = nbits; + + /* check if length is over-subscribed or incomplete */ + for (left = 1 << min, i = min; i <= max; left <<= 1, i++) { + left -= count[i]; + /* left < 0: over-subscribed, left > 0: incomplete */ + if (left < 0) + return -1; + } + + for (sum = 0, i = 0; i <= max; i++) { + offs[i] = sum; + sum += count[i]; + } + /* needed for decoding codes longer than nbits */ + if (nbits < max) + huff->sum = offs[nbits + 1]; + + /* sort symbols by code length (lexicographic order) */ + for (i = 0; i < n; i++) + if (lens[i]) + symbol[offs[lens[i]]++] = i; + + /* lookup table for decoding nbits from input.. */ + for (i = 0; i < 1 << nbits; i++) + table[i].len = table[i].sym = 0; + code = 0; + /* ..if code is at most nbits (bits are in reverse order, sigh..) */ + for (len = min; len <= nbits; len++) + for (c = count[len]; c > 0; c--) { + entry.len = len; + entry.sym = *symbol; + for (i = code; i < 1 << nbits; i += 1 << len) + table[i] = entry; + /* next code */ + symbol++; + code = revinc(code, len); + } + /* ..if code is longer than nbits: values for simple bitwise decode */ + for (i = 0; code; i++) { + table[code].len = -1; + table[code].sym = i << 1; + code = revinc(code, nbits); + } + return 0; +} + +/* fixed huffman code trees (should be done at compile time..) */ +static void init_fixed_huffs(void) { + int i; + uchar lens[Nlitlen]; + + for (i = 0; i < 144; i++) + lens[i] = 8; + for (; i < 256; i++) + lens[i] = 9; + for (; i < 280; i++) + lens[i] = 7; + for (; i < Nlitlen; i++) + lens[i] = 8; + build_huff(&lhuff, lens, Nlitlen, 8); + + for (i = 0; i < Ndist; i++) + lens[i] = 5; + build_huff(&dhuff, lens, Ndist, 5); +} + +/* fill *bits with n bits from *src */ +static int fillbits_fast(uchar **src, uchar *srcend, uint *bits, uint *nbits, uint n) { + while (*nbits < n) { + if (*src == srcend) + return 0; + *bits |= *(*src)++ << *nbits; + *nbits += 8; + } + return 1; +} + +/* get n bits from *bits */ +static uint getbits_fast(uint *bits, uint *nbits, int n) { + uint k; + + k = *bits & ((1 << n) - 1); + *bits >>= n; + *nbits -= n; + return k; +} + +static int fillbits(DecodeState *s, uint n) { + return fillbits_fast(&s->src, s->srcend, &s->bits, &s->nbits, n); +} + +static uint getbits(DecodeState *s, uint n) { + return getbits_fast(&s->bits, &s->nbits, n); +} + +/* decode symbol bitwise if code is longer than huffbits */ +static uint decode_symbol_long(DecodeState *s, Huff *huff, uint bits, uint nbits, int cur) { + int sum = huff->sum; + uint huffbits = huff->nbits; + ushort *count = huff->count + huffbits + 1; + + /* get bits if we are near the end */ + if (s->src + 2 >= s->srcend) { + while (nbits < CodeBits - 1 && s->src < s->srcend) { + bits |= *s->src++ << nbits; + nbits += 8; + } + s->bits = bits; + s->nbits = nbits; + } + bits >>= huffbits; + nbits -= huffbits; + for (;;) { + if (!nbits--) { + if (s->src == s->srcend) + return FlateIn; + bits = *s->src++; + nbits = 7; + } + cur |= bits & 1; + bits >>= 1; + sum += *count; + cur -= *count; + if (cur < 0) + break; + cur <<= 1; + count++; + if (count == huff->count + CodeBits) + return s->err = "symbol decoding failed.", FlateErr; + } + s->bits = bits; + s->nbits = nbits; + return huff->symbol[sum + cur]; +} + +/* decode a symbol from stream with huff code */ +static uint decode_symbol(DecodeState *s, Huff *huff) { + uint huffbits = huff->nbits; + uint nbits = s->nbits; + uint bits = s->bits; + uint mask = (1 << huffbits) - 1; + Entry entry; + + /* get enough bits efficiently */ + if (nbits < huffbits) { + uchar *src = s->src; + + if (src + 2 < s->srcend) { + /* we assume huffbits <= 9 */ + bits |= *src++ << nbits; + nbits += 8; + bits |= *src++ << nbits; + nbits += 8; + bits |= *src++ << nbits; + nbits += 8; + s->src = src; + } else /* rare */ + do { + if (s->src == s->srcend) { + entry = huff->table[bits & mask]; + if (entry.len > 0 && entry.len <= nbits) { + s->bits = bits >> entry.len; + s->nbits = nbits - entry.len; + return entry.sym; + } + s->bits = bits; + s->nbits = nbits; + return FlateIn; + } + bits |= *s->src++ << nbits; + nbits += 8; + } while (nbits < huffbits); + } + /* decode bits */ + entry = huff->table[bits & mask]; + if (entry.len > 0) { + s->bits = bits >> entry.len; + s->nbits = nbits - entry.len; + return entry.sym; + } else if (entry.len == 0) + return s->err = "symbol decoding failed.", FlateErr; + return decode_symbol_long(s, huff, bits, nbits, entry.sym); +} + +/* decode a block of data from stream with trees */ +static int decode_block(DecodeState *s, Huff *lhuff, Huff *dhuff) { + uchar *win = s->win; + uint pos = s->pos; + uint sym = s->nclen; + uint len = s->lenpos; + uint dist = s->nclen; + + switch (s->state) { + case DecodeBlock: + for (;;) { + sym = decode_symbol(s, lhuff); + if (sym < 256) { + win[pos++] = sym; + if (pos == WinSize) { + s->pos = WinSize; + s->state = DecodeBlock; + return FlateOut; + } + } else if (sym > 256) { + sym -= 257; + if (sym >= Nlen) { + s->pos = pos; + s->state = DecodeBlock; + if (sym + 257 == (uint)FlateIn) + return FlateIn; + return FlateErr; + } + case DecodeBlockLenBits: + if (!fillbits_fast(&s->src, s->srcend, &s->bits, &s->nbits, lenbits[sym])) { + s->nclen = sym; /* using nclen to store sym */ + s->pos = pos; + s->state = DecodeBlockLenBits; + return FlateIn; + } + len = lenbase[sym] + getbits_fast(&s->bits, &s->nbits, lenbits[sym]); + case DecodeBlockDist: + sym = decode_symbol(s, dhuff); + if (sym == (uint)FlateIn) { + s->pos = pos; + s->lenpos = len; + s->state = DecodeBlockDist; + return FlateIn; + } + if (sym >= Ndist) + return FlateErr; + case DecodeBlockDistBits: + if (!fillbits_fast(&s->src, s->srcend, &s->bits, &s->nbits, distbits[sym])) { + s->nclen = sym; /* using nclen to store sym */ + s->pos = pos; + s->lenpos = len; + s->state = DecodeBlockDistBits; + return FlateIn; + } + dist = distbase[sym] + getbits_fast(&s->bits, &s->nbits, distbits[sym]); + /* copy match, loop unroll in common case */ + if (pos + len < WinSize) { + /* lenbase[sym] >= 3 */ + do { + win[pos] = win[(pos - dist) % WinSize]; + pos++; + win[pos] = win[(pos - dist) % WinSize]; + pos++; + win[pos] = win[(pos - dist) % WinSize]; + pos++; + len -= 3; + } while (len >= 3); + if (len--) { + win[pos] = win[(pos - dist) % WinSize]; + pos++; + if (len) { + win[pos] = win[(pos - dist) % WinSize]; + pos++; + } + } + } else { /* rare */ + case DecodeBlockCopy: + while (len--) { + win[pos] = win[(pos - dist) % WinSize]; + pos++; + if (pos == WinSize) { + s->pos = WinSize; + s->lenpos = len; + s->nclen = dist; /* using nclen to store dist */ + s->state = DecodeBlockCopy; + return FlateOut; + } + } + } + } else { /* EOB: sym == 256 */ + s->pos = pos; + return FlateOk; + } + } /* for (;;) */ + } /* switch () */ + return s->err = "corrupted state.", FlateErr; +} + +/* inflate state machine (decodes s->src into s->win) */ +static int inflate_state(DecodeState *s) { + int n; + + if (s->posout) + return FlateOut; + for (;;) { + switch (s->state) { + case BlockHead: + if (s->final) { + if (s->pos) + return FlateOut; + else + return FlateOk; + } + if (!fillbits(s, 3)) + return FlateIn; + s->final = getbits(s, 1); + n = getbits(s, 2); + if (n == 0) + s->state = UncompressedBlock; + else if (n == 1) + s->state = FixedHuff; + else if (n == 2) + s->state = DynamicHuff; + else + return s->err = "corrupt block header.", FlateErr; + break; + case UncompressedBlock: + /* start block on a byte boundary */ + s->bits >>= s->nbits & 7; + s->nbits &= ~7; + if (!fillbits(s, 32)) + return FlateIn; + s->lenpos = getbits(s, 16); + n = getbits(s, 16); + if (s->lenpos != (~n & 0xffff)) + return s->err = "corrupt uncompressed length.", FlateErr; + s->state = CopyUncompressed; + case CopyUncompressed: + /* TODO: untested, slow, memcpy etc */ + /* s->nbits should be 0 here */ + while (s->lenpos) { + if (s->src == s->srcend) + return FlateIn; + s->lenpos--; + s->win[s->pos++] = *s->src++; + if (s->pos == WinSize) + return FlateOut; + } + s->state = BlockHead; + break; + case FixedHuff: + s->fixed = 1; + s->state = DecodeBlock; + break; + case DynamicHuff: + /* decode dynamic huffman code trees */ + if (!fillbits(s, 14)) + return FlateIn; + s->nlit = 257 + getbits(s, 5); + s->ndist = 1 + getbits(s, 5); + s->nclen = 4 + getbits(s, 4); + if (s->nlit > Nlitlen || s->ndist > Ndist) + return s->err = "corrupt code tree.", FlateErr; + /* build code length tree */ + for (n = 0; n < Nclen; n++) + s->lens[n] = 0; + s->fixed = 0; + s->state = DynamicHuffClen; + s->lenpos = 0; + case DynamicHuffClen: + for (n = s->lenpos; n < s->nclen; n++) + if (fillbits(s, 3)) { + s->lens[clenorder[n]] = getbits(s, 3); + } else { + s->lenpos = n; + return FlateIn; + } + /* using lhuff for code length huff code */ + if (build_huff(&s->lhuff, s->lens, Nclen, ClenTableBits) < 0) + return s->err = "building clen tree failed.", FlateErr; + s->state = DynamicHuffLitlenDist; + s->lenpos = 0; + case DynamicHuffLitlenDist: + /* decode code lengths for the dynamic trees */ + for (n = s->lenpos; n < s->nlit + s->ndist; ) { + uint sym = decode_symbol(s, &s->lhuff); + uint len; + uchar c; + + if (sym < 16) { + s->lens[n++] = sym; + continue; + } else if (sym == (uint)FlateIn) { + s->lenpos = n; + return FlateIn; + case DynamicHuffContinue: + n = s->lenpos; + sym = s->nclen; + s->state = DynamicHuffLitlenDist; + } + if (!fillbits(s, 7)) { + /* TODO: 7 is too much when an almost empty block is at the end */ + if (sym == (uint)FlateErr) + return FlateErr; + s->nclen = sym; + s->lenpos = n; + s->state = DynamicHuffContinue; + return FlateIn; + } + /* TODO: bound check s->lens */ + if (sym == 16) { + /* copy previous code length 3-6 times */ + c = s->lens[n - 1]; + for (len = 3 + getbits(s, 2); len; len--) + s->lens[n++] = c; + } else if (sym == 17) { + /* repeat 0 for 3-10 times */ + for (len = 3 + getbits(s, 3); len; len--) + s->lens[n++] = 0; + } else if (sym == 18) { + /* repeat 0 for 11-138 times */ + for (len = 11 + getbits(s, 7); len; len--) + s->lens[n++] = 0; + } else + return s->err = "corrupt code tree.", FlateErr; + } + /* build dynamic huffman code trees */ + if (build_huff(&s->lhuff, s->lens, s->nlit, LitlenTableBits) < 0) + return s->err = "building litlen tree failed.", FlateErr; + if (build_huff(&s->dhuff, s->lens + s->nlit, s->ndist, DistTableBits) < 0) + return s->err = "building dist tree failed.", FlateErr; + s->state = DecodeBlock; + case DecodeBlock: + case DecodeBlockLenBits: + case DecodeBlockDist: + case DecodeBlockDistBits: + case DecodeBlockCopy: + n = decode_block(s, s->fixed ? &lhuff : &s->lhuff, s->fixed ? &dhuff : &s->dhuff); + if (n != FlateOk) + return n; + s->state = BlockHead; + break; + default: + return s->err = "corrupt internal state.", FlateErr; + } + } +} + +static DecodeState *alloc_decode_state(void) { + DecodeState *s = malloc(sizeof(DecodeState)); + + if (s) { + s->final = s->pos = s->posout = s->bits = s->nbits = 0; + s->state = BlockHead; + s->src = s->srcend = 0; + s->err = 0; + /* TODO: globals.. */ + if (lhuff.nbits == 0) + init_fixed_huffs(); + } + return s; +} + + +/* extern */ + +int inflate(FlateStream *stream) { + DecodeState *s = stream->state; + int n; + + if (stream->err) { + if (s) { + free(s); + stream->state = 0; + } + return FlateErr; + } + if (!s) { + s = stream->state = alloc_decode_state(); + if (!s) + return stream->err = "no mem.", FlateErr; + } + if (stream->nin) { + s->src = stream->in; + s->srcend = s->src + stream->nin; + stream->nin = 0; + } + n = inflate_state(s); + if (n == FlateOut) { + if (s->pos < stream->nout) + stream->nout = s->pos; + memcpy(stream->out, s->win + s->posout, stream->nout); + s->pos -= stream->nout; + if (s->pos) + s->posout += stream->nout; + else + s->posout = 0; + } + if (n == FlateOk || n == FlateErr) { + if (s->nbits || s->src < s->srcend) { + s->nbits /= 8; + stream->in = s->src - s->nbits; + stream->nin = s->srcend - s->src + s->nbits; + } + stream->err = s->err; + free(s); + stream->state = 0; + } + return n; +} + +typedef struct { + ushort dist; + ushort len; +} Match; + +typedef struct { + ushort n; + ushort bits; +} LzCode; + +typedef struct { + int pos; /* position in input src */ + int startpos; /* block start pos in input src */ + int endpos; /* end of available bytes in src */ + int skip; /* skipped hash chain updates (until next iter) */ + Match prevm; /* previous (deferred) match */ + int state; /* prev return value */ + int eof; /* end of input */ + uchar *in; /* input data (not yet in src) */ + uchar *inend; + uint bits; /* for output */ + int nbits; /* for output */ + uchar *dst; /* compressed output (position in dstbuf) */ + uchar *dstbegin; /* start position of unflushed data in dstbuf */ + LzCode *lz; /* current pos in lzbuf */ + int nlit; /* literal run length in lzbuf */ + ushort head[HashSize]; /* position of hash chain heads */ + ushort chain[WinSize]; /* hash chain */ + ushort lfreq[Nlitlen]; + ushort dfreq[Ndist]; + uchar src[SrcSize]; /* input buf */ + uchar dstbuf[DstSize]; + LzCode lzbuf[LzSize]; /* literal run length, match len, match dist */ +} State; + +static uchar fixllen[Nlitlen]; /* fixed lit/len huffman code tree */ +static ushort fixlcode[Nlitlen]; +static uchar fixdlen[Ndist]; /* fixed distance huffman code tree */ +static ushort fixdcode[Ndist]; + +static uint revcode(uint c, int n) { + int i; + uint r = 0; + + for (i = 0; i < n; i++) { + r = (r << 1) | (c & 1); + c >>= 1; + } + return r; +} + +/* build huffman code tree from code lengths */ +static void huffcodes(ushort *codes, const uchar *lens, int n) { + int c[CodeBits]; + int i, code, count; + + /* count code lengths and calc first code for each length */ + for (i = 0; i < CodeBits; i++) + c[i] = 0; + for (i = 0; i < n; i++) + c[lens[i]]++; + for (code = 0, i = 1; i < CodeBits; i++) { + count = c[i]; + c[i] = code; + code += count; + if (code > (1 << i)) + abort(); /* over-subscribed */ + code <<= 1; + } + if (code < (1 << i)) + /* incomplete */; + + for (i = 0; i < n; i++) + if (lens[i]) + codes[i] = revcode(c[lens[i]]++, lens[i]); + else + codes[i] = 0; +} + +static int heapparent(int n) {return (n - 2)/4 * 2;} +static int heapchild(int n) {return 2 * n + 2;} + +static int heappush(int *heap, int len, int w, int n) { + int p, c, tmp; + + c = len; + heap[len++] = n; + heap[len++] = w; + while (c > 0) { + p = heapparent(c); + if (heap[c+1] < heap[p+1]) { + tmp = heap[c]; heap[c] = heap[p]; heap[p] = tmp; + tmp = heap[c+1]; heap[c+1] = heap[p+1]; heap[p+1] = tmp; + c = p; + } else + break; + } + return len; +} + +static int heappop(int *heap, int len, int *w, int *n) { + int p, c, tmp; + + *n = heap[0]; + *w = heap[1]; + heap[1] = heap[--len]; + heap[0] = heap[--len]; + p = 0; + for (;;) { + c = heapchild(p); + if (c >= len) + break; + if (c+2 < len && heap[c+3] < heap[c+1]) + c += 2; + if (heap[p+1] > heap[c+1]) { + tmp = heap[p]; heap[p] = heap[c]; heap[c] = tmp; + tmp = heap[p+1]; heap[p+1] = heap[c+1]; heap[c+1] = tmp; + } else + break; + p = c; + } + return len; +} + +/* symbol frequencies -> code lengths (limited to 255) */ +static void hufflens(uchar *lens, ushort *freqs, int nsym, int limit) { + /* 2 <= nsym <= Nlitlen, log(nsym) <= limit <= CodeBits-1 */ + int parent[2*Nlitlen-1]; + int count[CodeBits]; + int heap[2*Nlitlen]; + int n, len, top, overflow; + int i, j; + int wi, wj; + + for (n = 0; n < limit+1; n++) + count[n] = 0; + for (len = n = 0; n < nsym; n++) + if (freqs[n] > 0) + len = heappush(heap, len, freqs[n], n); + else + lens[n] = 0; + /* deflate: fewer than two symbols: add new */ + for (n = 0; len < 4; n++) + if (freqs[n] == 0) + len = heappush(heap, len, ++freqs[n], n); + /* build code tree */ + top = len; + for (n = nsym; len > 2; n++) { + len = heappop(heap, len, &wi, &i); + len = heappop(heap, len, &wj, &j); + parent[i] = n; + parent[j] = n; + len = heappush(heap, len, wi + wj, n); + /* keep an ordered list of nodes at the end */ + heap[len+1] = i; + heap[len] = j; + } + /* calc code lengths (deflate: with limit) */ + overflow = 0; + parent[--n] = 0; + for (i = 2; i < top; i++) { + n = heap[i]; + if (n >= nsym) { + /* overwrite parent index with length */ + parent[n] = parent[parent[n]] + 1; + if (parent[n] > limit) + overflow++; + } else { + lens[n] = parent[parent[n]] + 1; + if (lens[n] > limit) { + lens[n] = limit; + overflow++; + } + count[lens[n]]++; + } + } + if (overflow == 0) + return; + /* modify code tree to fix overflow (from zlib) */ + while (overflow > 0) { + for (n = limit-1; count[n] == 0; n--); + count[n]--; + count[n+1] += 2; + count[limit]--; + overflow -= 2; + } + for (len = limit; len > 0; len--) + for (i = count[len]; i > 0;) { + n = heap[--top]; + if (n < nsym) { + lens[n] = len; + i--; + } + } +} + +/* output n (<= 16) bits */ +static void putbits(State *s, uint bits, int n) { + s->bits |= bits << s->nbits; + s->nbits += n; + while (s->nbits >= 8) { + *s->dst++ = s->bits & 0xff; + s->bits >>= 8; + s->nbits -= 8; + } +} + +/* run length encode literal and dist code lengths into codes and extra */ +static int clencodes(uchar *codes, uchar *extra, uchar *llen, int nlit, uchar *dlen, int ndist) { + int i, c, r, rr; + int n = 0; + + for (i = 0; i < nlit; i++) + codes[i] = llen[i]; + for (i = 0; i < ndist; i++) + codes[nlit + i] = dlen[i]; + for (i = 0; i < nlit + ndist;) { + c = codes[i]; + for (r = 1; i + r < nlit + ndist && codes[i + r] == c; r++); + i += r; + if (c == 0) { + while (r >= 11) { + rr = r > 138 ? 138 : r; + codes[n] = 18; + extra[n++] = rr - 11; + r -= rr; + } + if (r >= 3) { + codes[n] = 17; + extra[n++] = r - 3; + r = 0; + } + } + while (r--) { + codes[n++] = c; + while (r >= 3) { + rr = r > 6 ? 6 : r; + codes[n] = 16; + extra[n++] = rr - 3; + r -= rr; + } + } + } + return n; +} + +/* compress block data into s->dstbuf using given codes */ +static void putblock(State *s, ushort *lcode, uchar *llen, ushort *dcode, uchar *dlen) { + int n; + LzCode *lz; + uchar *p; + + for (lz = s->lzbuf, p = s->src + s->startpos; lz != s->lz; lz++) + if (lz->bits & LzLitFlag) + for (n = lz->n; n > 0; n--, p++) + putbits(s, lcode[*p], llen[*p]); + else { + p += lenbase[lz->n] + lz->bits; + putbits(s, lcode[Nlit + lz->n + 1], llen[Nlit + lz->n + 1]); + putbits(s, lz->bits, lenbits[lz->n]); + lz++; + putbits(s, dcode[lz->n], dlen[lz->n]); + putbits(s, lz->bits, distbits[lz->n]); + } + putbits(s, lcode[EOB], llen[EOB]); +} + +/* build code trees and select dynamic/fixed/uncompressed block compression */ +static void deflate_block(State *s) { + uchar codes[Nlitlen + Ndist], extra[Nlitlen + Ndist]; + uchar llen[Nlitlen], dlen[Ndist], clen[Nclen]; + ushort cfreq[Nclen]; + /* freq can be overwritten by code */ + ushort *lcode = s->lfreq, *dcode = s->dfreq, *ccode = cfreq; + int i, c, n, ncodes; + int nlit, ndist, nclen; + LzCode *lz; + uchar *p; + int dynsize, fixsize, uncsize; + int blocklen = s->pos - s->startpos; +/* int dyntree; */ + + /* calc dynamic codes */ + hufflens(llen, s->lfreq, Nlitlen, CodeBits-1); + hufflens(dlen, s->dfreq, Ndist, CodeBits-1); + huffcodes(lcode, llen, Nlitlen); + huffcodes(dcode, dlen, Ndist); + for (nlit = Nlitlen; nlit > Nlit && llen[nlit-1] == 0; nlit--); + for (ndist = Ndist; ndist > 1 && dlen[ndist-1] == 0; ndist--); + ncodes = clencodes(codes, extra, llen, nlit, dlen, ndist); + memset(cfreq, 0, sizeof(cfreq)); + for (i = 0; i < ncodes; i++) + cfreq[codes[i]]++; + hufflens(clen, cfreq, Nclen, 7); + huffcodes(ccode, clen, Nclen); + for (nclen = Nclen; nclen > 4 && clen[clenorder[nclen-1]] == 0; nclen--); + + /* calc compressed size */ + uncsize = 3 + 16 + 8 * blocklen + (16 - 3 - s->nbits) % 8; /* byte aligned */ + fixsize = 3; + dynsize = 3 + 5 + 5 + 4 + 3 * nclen; + for (i = 0; i < ncodes; i++) { + c = codes[i]; + dynsize += clen[c]; + if (c == 16) + dynsize += 2; + if (c == 17) + dynsize += 3; + if (c == 18) + dynsize += 7; + } +/* dyntree = dynsize - 3; */ + for (lz = s->lzbuf, p = s->src + s->startpos; lz != s->lz; lz++) + if (lz->bits & LzLitFlag) + for (n = lz->n; n > 0; n--, p++) { + fixsize += fixllen[*p]; + dynsize += llen[*p]; + } + else { + p += lenbase[lz->n] + lz->bits; + fixsize += fixllen[Nlit + lz->n + 1]; + dynsize += llen[Nlit + lz->n + 1]; + fixsize += lenbits[lz->n]; + dynsize += lenbits[lz->n]; + lz++; + fixsize += fixdlen[lz->n]; + dynsize += dlen[lz->n]; + fixsize += distbits[lz->n]; + dynsize += distbits[lz->n]; + } + fixsize += fixllen[EOB]; + dynsize += llen[EOB]; + + /* emit block */ + putbits(s, s->eof && s->pos == s->endpos, 1); + if (dynsize < fixsize && dynsize < uncsize) { + /* dynamic code */ + putbits(s, 2, 2); + putbits(s, nlit - 257, 5); + putbits(s, ndist - 1, 5); + putbits(s, nclen - 4, 4); + for (i = 0; i < nclen; i++) + putbits(s, clen[clenorder[i]], 3); + for (i = 0; i < ncodes; i++) { + c = codes[i]; + putbits(s, ccode[c], clen[c]); + if (c == 16) + putbits(s, extra[i], 2); + if (c == 17) + putbits(s, extra[i], 3); + if (c == 18) + putbits(s, extra[i], 7); + } + putblock(s, lcode, llen, dcode, dlen); + } else if (fixsize < uncsize) { + /* fixed code */ + putbits(s, 1, 2); + putblock(s, fixlcode, fixllen, fixdcode, fixdlen); + } else { + /* uncompressed */ + putbits(s, 0, 2); + putbits(s, 0, 7); /* align to byte boundary */ + s->nbits = 0; + putbits(s, blocklen, 16); + putbits(s, ~blocklen & 0xffff, 16); + memcpy(s->dst, s->src + s->startpos, blocklen); + s->dst += blocklen; + } +/* +fprintf(stderr, "blen:%d [%d,%d] lzlen:%d dynlen:%d (tree:%d rate:%.3f) fixlen:%d (rate:%.3f) unclen:%d (rate:%.3f)\n", + blocklen, s->startpos, s->pos, s->lz - s->lzbuf, dynsize, dyntree, dynsize/(float)blocklen, + fixsize, fixsize/(float)blocklen, uncsize, uncsize/(float)blocklen); +*/ +} + +/* find n in base */ +static int bisect(ushort *base, int len, int n) { + int lo = 0; + int hi = len; + int k; + + while (lo < hi) { + k = (lo + hi) / 2; + if (n < base[k]) + hi = k; + else + lo = k + 1; + } + return lo - 1; +} + +/* add literal run length to lzbuf */ +static void flushlit(State *s) { + if (s->nlit) { + s->lz->bits = LzLitFlag; + s->lz->n = s->nlit; + s->lz++; + s->nlit = 0; + } +} + +/* add match to lzbuf and update freq counts */ +static void recordmatch(State *s, Match m) { + int n; + +/*fprintf(stderr, "m %d %d\n", m.len, m.dist);*/ + flushlit(s); + n = bisect(lenbase, Nlen, m.len); + s->lz->n = n; + s->lz->bits = m.len - lenbase[n]; + s->lz++; + s->lfreq[Nlit + n + 1]++; + n = bisect(distbase, Ndist, m.dist); + s->lz->n = n; + s->lz->bits = m.dist - distbase[n]; + s->lz++; + s->dfreq[n]++; +} + +/* update literal run length */ +static void recordlit(State *s, int c) { +/*fprintf(stderr, "l %c\n", c);*/ + s->nlit++; + s->lfreq[c]++; +} + +/* multiplicative hash (using a prime close to golden ratio * 2^32) */ +static int gethash(uchar *p) { + return (0x9e3779b1 * ((p[0]<<16) + (p[1]<<8) + p[2]) >> (32 - HashBits)) % HashSize; +} + +/* update hash chain at the current position */ +static int updatechain(State *s) { + int hash, next = 0, p = s->pos, i; + + if (s->endpos - p < MinMatch) + p = s->endpos - MinMatch; + for (i = s->pos - s->skip; i <= p; i++) { + hash = gethash(s->src + i); + next = s->head[hash]; + s->head[hash] = i; + if (next >= i || i - next >= MaxDist) + next = 0; + s->chain[i % WinSize] = next; + } + s->skip = 0; + return next; +} + +/* find longest match, next position in the hash chain is given */ +static Match getmatch(State *s, int next) { + Match m = {0, MinMatch-1}; + int len; + int limit = s->pos - MaxDist; + int chainlen = MaxChainLen; + uchar *q; + uchar *p = s->src + s->pos; + uchar *end = p + MaxMatch; + + do { + q = s->src + next; +/*fprintf(stderr,"match: next:%d pos:%d limit:%d\n", next, s->pos, limit);*/ + /* next match should be at least m.len+1 long */ + if (q[m.len] != p[m.len] || q[m.len-1] != p[m.len-1] || q[0] != p[0]) + continue; + while (++p != end && *++q == *p); + len = MaxMatch - (end - p); + p -= len; +/*fprintf(stderr,"match: len:%d dist:%d\n", len, s->pos - next);*/ + if (len > m.len) { + m.dist = s->pos - next; + m.len = len; + if (s->pos + len >= s->endpos) { /* TODO: overflow */ + m.len = s->endpos - s->pos; + return m; + } + if (len == MaxMatch) + return m; + } + } while ((next = s->chain[next % WinSize]) > limit && --chainlen); + if (m.len < MinMatch || (m.len == MinMatch && m.dist > BigDist)) + m.len = 0; + return m; +} + +static void startblock(State *s) { + s->startpos = s->pos; + s->dst = s->dstbegin = s->dstbuf; + s->lz = s->lzbuf; + s->nlit = 0; + memset(s->lfreq, 0, sizeof(s->lfreq)); + memset(s->dfreq, 0, sizeof(s->dfreq)); + s->lfreq[EOB]++; +} + +static int shiftwin(State *s) { + int n; + + if (s->startpos < WinSize) + return 0; + memmove(s->src, s->src + WinSize, SrcSize - WinSize); + for (n = 0; n < HashSize; n++) + s->head[n] = s->head[n] > WinSize ? s->head[n] - WinSize : 0; + for (n = 0; n < WinSize; n++) + s->chain[n] = s->chain[n] > WinSize ? s->chain[n] - WinSize : 0; + s->pos -= WinSize; + s->startpos -= WinSize; + s->endpos -= WinSize; + return 1; +} + +static int endblock(State *s) { + if ((s->pos >= 2*WinSize && !shiftwin(s)) || s->pos - s->startpos >= BlockSize || + s->lz - s->lzbuf >= LzGuard || (s->eof && s->pos == s->endpos)) { + /* deflate block */ + flushlit(s); + if (s->prevm.len) + s->pos--; + deflate_block(s); + if (s->eof && s->pos == s->endpos) + putbits(s, 0, 7); + return 1; + } + return 0; +} + +static int fillsrc(State *s) { + int n, k; + + if (s->endpos < SrcSize && !s->eof) { + n = SrcSize - s->endpos; + k = s->inend - s->in; + if (n > k) + n = k; + memcpy(s->src + s->endpos, s->in, n); + s->in += n; + s->endpos += n; + if (s->endpos < SrcSize) + return 0; + } + return 1; +} + +static int calcguard(State *s) { + int p = s->endpos - MaxMatch; + int q = s->startpos + BlockSize; + + return p < q ? p : q; +} + +/* deflate compress from s->src into s->dstbuf */ +static int deflate_state(State *s) { + Match m; + int next; + int guard; + + if (s->state == FlateIn) + s->eof = s->in == s->inend; + else if (s->state == FlateOut) { + if (s->dstbegin < s->dst) + return (s->state = FlateOut); + if (s->eof && s->pos == s->endpos) + return (s->state = FlateOk); + startblock(s); + if (s->prevm.len) + s->pos++; + } else + return s->state; + + guard = calcguard(s); + for (;;) { + if (s->pos >= guard || s->lz - s->lzbuf >= LzGuard) { +/*fprintf(stderr,"guard:%d pos:%d len:%d lzlen:%d end:%d start:%d nin:%d eof:%d\n", guard, s->pos, s->pos - s->startpos, s->lz - s->lzbuf, s->endpos, s->startpos, s->inend - s->in, s->eof);*/ + if (endblock(s)) + return (s->state = FlateOut); + if (!fillsrc(s)) + return (s->state = FlateIn); + guard = calcguard(s); + } + next = updatechain(s); + if (next) + m = getmatch(s, next); + if (next && m.len > s->prevm.len) { + if (s->prevm.len) + recordlit(s, s->src[s->pos-1]); + s->prevm = m; + } else if (s->prevm.len) { + recordmatch(s, s->prevm); + s->skip = s->prevm.len - 2; + s->prevm.len = 0; + s->pos += s->skip; + } else + recordlit(s, s->src[s->pos]); + s->pos++; + } +} + +/* alloc and init state */ +static State *alloc_state(void) { + State *s = malloc(sizeof(State)); + int i; + + if (!s) + return s; + memset(s->chain, 0, sizeof(s->chain)); + memset(s->head, 0, sizeof(s->head)); + s->bits = s->nbits = 0; + /* TODO: globals */ + if (fixllen[0] == 0) { + for (i = 0; i < 144; i++) + fixllen[i] = 8; + for (; i < 256; i++) + fixllen[i] = 9; + for (; i < 280; i++) + fixllen[i] = 7; + for (; i < Nlitlen; i++) + fixllen[i] = 8; + for (i = 0; i < Ndist; i++) + fixdlen[i] = 5; + huffcodes(fixlcode, fixllen, Nlitlen); + huffcodes(fixdcode, fixdlen, Ndist); + } + s->state = FlateOut; + s->in = s->inend = 0; + s->dst = s->dstbegin = s->dstbuf; + s->pos = s->startpos = s->endpos = WinSize; + s->eof = 0; + s->skip = 0; + s->prevm.len = 0; + return s; +} + + +/* extern */ + +int deflate(FlateStream *stream) { + State *s = stream->state; + int n, k; + + if (stream->err) { + free(s); + stream->state = 0; + return FlateErr; + } + if (!s) { + s = stream->state = alloc_state(); + if (!s) + return stream->err = "no mem.", FlateErr; + } + if (stream->nin) { + s->in = stream->in; + s->inend = s->in + stream->nin; + stream->nin = 0; + } + n = deflate_state(s); + if (n == FlateOut) { + k = s->dst - s->dstbegin; + if (k < stream->nout) + stream->nout = k; + memcpy(stream->out, s->dstbegin, stream->nout); + s->dstbegin += stream->nout; + } + if (n == FlateOk || n == FlateErr) { + free(s); + stream->state = 0; + } + return n; +} + +static void set32(uchar *p, uint n) { + p[0] = n >> 24; + p[1] = n >> 16; + p[2] = n >> 8; + p[3] = n; +} + +static void set32le(uchar *p, uint n) { + p[0] = n; + p[1] = n >> 8; + p[2] = n >> 16; + p[3] = n >> 24; +} + +static int check32(uchar *p, uint n) { + return n == ((p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3]); +} + +static int check32le(uchar *p, uint n) { + return n == (p[0] | (p[1] << 8) | (p[2] << 16) | (p[3] << 24)); +} + +enum { + ZlibCM = 7 << 4, + ZlibCINFO = 8, + ZlibFLEV = 3 << 6, + ZlibFDICT = 1 << 5, + ZlibFCHK = 31 - (((ZlibCM | ZlibCINFO) << 8) | ZlibFLEV) % 31 +}; + +int deflate_zlib_header(uchar *p, int n) { + if (n < 2) + return FlateErr; + p[0] = ZlibCM | ZlibCINFO; /* deflate method, 32K window size */ + p[1] = ZlibFLEV | ZlibFCHK; /* highest compression */ + return 2; +} + +int deflate_zlib_footer(uchar *p, int n, uint sum, uint len, uint zlen) { + if (n < 4) + return FlateErr; + set32(p, sum); + return 4; +} + +int inflate_zlib_header(uchar *p, int n) { + if (n < 2) + return FlateErr; + if (((p[0] << 8) | p[1]) % 31) + return FlateErr; + if ((p[0] & 0xf0) != ZlibCM || (p[0] & 0x0f) > ZlibCINFO) + return FlateErr; + if (p[1] & ZlibFDICT) + return FlateErr; + return 2; +} + +int inflate_zlib_footer(uchar *p, int n, uint sum, uint len, uint zlen) { + if (n < 4 || !check32(p, sum)) + return FlateErr; + return 4; +} + + +enum { + GZipID1 = 0x1f, + GZipID2 = 0x8b, + GZipCM = 8, + GZipFHCRC = 1 << 1, + GZipFEXTRA = 1 << 2, + GZipFNAME = 1 << 3, + GZipFCOMM = 1 << 4, + GZipXFL = 2, + GZipOS = 255 +}; + +int deflate_gzip_header(uchar *p, int n) { + if (n < 10) + return FlateErr; + memset(p, 0, 10); + p[0] = GZipID1; + p[1] = GZipID2; + p[2] = GZipCM; + p[8] = GZipXFL; + p[9] = GZipOS; + return 10; +} + +int deflate_gzip_footer(uchar *p, int n, uint sum, uint len, uint zlen) { + if (n < 8) + return FlateErr; + set32le(p, sum); + set32le(p+4, len); + return 8; +} + +int inflate_gzip_header(uchar *p, int n) { + int k = 10; + + if (k > n) + return FlateErr; + if (p[0] != GZipID1 || p[1] != GZipID2 || p[2] != GZipCM) + return FlateErr; + if (p[3] & GZipFEXTRA) { + k += 2 + ((p[k] << 8) | p[k+1]); + if (k > n) + return FlateErr; + } + if (p[3] & GZipFNAME) { + for (; k < n; k++) + if (p[k] == 0) + break; + k++; + if (k > n) + return FlateErr; + } + if (p[3] & GZipFCOMM) { + for (; k < n; k++) + if (p[k] == 0) + break; + k++; + if (k > n) + return FlateErr; + } + if (p[3] & GZipFHCRC) { + k += 2; + if (k > n) + return FlateErr; + } + return k; +} + +int inflate_gzip_footer(uchar *p, int n, uint sum, uint len, uint zlen) { + if (n < 8 || !check32le(p, sum) || !check32le(p+4, len)) + return FlateErr; + return 8; +} + + +static char pkname[] = "sflate_stream"; + +enum { + PKHeadID = 0x04034b50, + PKDataID = 0x08074b50, + PKDirID = 0x02014b50, + PKFootID = 0x06054b50, + PKVersion = 20, + PKFlag = 1 << 3, + PKMethod = 8, + PKDate = ((2009 - 1980) << 25) | (1 << 21) | (1 << 16), + PKHeadSize = 30, + PKDirSize = 46, + PKNameLen = sizeof(pkname) - 1 +}; + +int deflate_pkzip_header(uchar *p, int n) { + if (n < PKHeadSize + PKNameLen) + return FlateErr; + memset(p, 0, PKHeadSize); + set32le(p, PKHeadID); + set32le(p+4, PKVersion); + set32le(p+6, PKFlag); + set32le(p+8, PKMethod); + set32le(p+10, PKDate); + set32le(p+26, PKNameLen); + memcpy(p + PKHeadSize, pkname, PKNameLen); + return PKHeadSize + PKNameLen; +} + +int deflate_pkzip_footer(uchar *p, int n, uint sum, uint len, uint zlen) { + if (n < PKDirSize + PKNameLen + 22) + return FlateErr; + /* unzip bug */ +/* + if (n < 16 + PKDirSize + PKNameLen + 22) + return FlateErr; + set32le(p, PKDataID); + set32le(p+4, sum); + set32le(p+8, zlen); + set32le(p+12, len); + p += 16; +*/ + memset(p, 0, PKDirSize); + set32le(p, PKDirID); + set32le(p+4, PKVersion | (PKVersion << 16)); + set32le(p+8, PKFlag); + set32le(p+10, PKMethod); + set32le(p+12, PKDate); + set32le(p+16, sum); + set32le(p+20, zlen); + set32le(p+24, len); + set32le(p+28, PKNameLen); + memcpy(p + PKDirSize, pkname, PKNameLen); + p += PKDirSize + PKNameLen; + memset(p, 0, 22); + set32le(p, PKFootID); + p[8] = p[10] = 1; + set32le(p+12, PKDirSize + PKNameLen); + set32le(p+16, zlen + PKHeadSize + PKNameLen); + return PKDirSize + PKNameLen + 22; +/* + set32le(p+12, 16 + PKDirSize + PKNameLen); + set32le(p+16, zlen + PKHeadSize + PKNameLen); + return 16 + PKDirSize + PKNameLen + 22; +*/ +} + +int inflate_pkzip_header(uchar *p, int n) { + int k = 30; + + if (k > n) + return FlateErr; + if (!check32le(p, PKHeadID)) + return FlateErr; + if ((p[4] | (p[5] << 8)) > PKVersion) + return FlateErr; + if ((p[8] | (p[9] << 8)) != PKMethod) + return FlateErr; + k += p[26] | (p[27] << 8); + k += p[28] | (p[29] << 8); + if (k > n) + return FlateErr; + return k; +} + +int inflate_pkzip_footer(uchar *p, int n, uint sum, uint len, uint zlen) { + int k = PKDirSize + 22; + + if (k > n) + return FlateErr; + if (check32le(p, PKDataID)) { + p += 16; + k += 16; + if (k > n) + return FlateErr; + } + if (!check32le(p, PKDirID)) + return FlateErr; + if (!check32le(p+16, sum)) + return FlateErr; + if (!check32le(p+20, zlen)) + return FlateErr; + if (!check32le(p+24, len)) + return FlateErr; + return k; +} + + +/* example usage */ + +static int (*header)(uchar *, int); +static int (*footer)(uchar *, int, uint, uint, uint); +static uint (*checksum)(uchar *, int, uint); +static char *err; +static uint sum; +static uint nin; +static uint nout; +static uint headerlen; +static uint footerlen; +static uint extralen; + +static int dummyheader(uchar *p, int n) { + return 0; +} +static int dummyfooter(uchar *p, int n, uint sum, uint len, uint zlen) { + return 0; +} +static uint dummysum(uchar *p, int n, uint sum) { + return 0; +} + +/* compress, using FlateStream interface */ +int compress_stream(FILE *in, FILE *out) { + FlateStream s; + int k, n; + enum {Nin = 1<<15, Nout = 1<<15}; + + s.in = malloc(Nin); + s.out = malloc(Nout); + s.nin = 0; + s.nout = Nout; + s.err = 0; + s.state = 0; + + k = header(s.out, s.nout); + if (k == FlateErr) { + s.err = "header error."; + n = FlateErr; + } else { + headerlen = s.nout = k; + n = FlateOut; + } + for (;; n = deflate(&s)) + switch (n) { + case FlateOk: + k = footer(s.out, s.nout, sum, nin, nout - headerlen); + if (k == FlateErr) { + s.err = "footer error."; + n = FlateErr; + } else if (k != fwrite(s.out, 1, k, out)) { + s.err = "write error."; + n = FlateErr; + } else { + footerlen = k; + nout += k; + } + case FlateErr: + free(s.in); + free(s.out); + err = s.err; + return n; + case FlateIn: + s.nin = fread(s.in, 1, Nin, in); + nin += s.nin; + sum = checksum(s.in, s.nin, sum); + break; + case FlateOut: + k = fwrite(s.out, 1, s.nout, out); + if (k != s.nout) + s.err = "write error."; + nout += k; + s.nout = Nout; + break; + } +} + +/* decompress, using FlateStream interface */ +int decompress_stream(FILE *in, FILE *out) { + FlateStream s; + uchar *begin; + int k, n; + enum {Nin = 1<<15, Nout = 1<<15}; + + s.in = begin = malloc(Nin); + s.out = malloc(Nout); + s.nout = Nout; + s.err = 0; + s.state = 0; + + s.nin = fread(s.in, 1, Nin, in); + nin += s.nin; + k = header(s.in, s.nin); + if (k == FlateErr) { + s.err = "header error."; + n = FlateErr; + } else { + headerlen = k; + s.nin -= k; + s.in += k; + n = inflate(&s); + } + for (;; n = inflate(&s)) + switch (n) { + case FlateOk: + memmove(begin, s.in, s.nin); + k = fread(begin, 1, Nin-s.nin, in); + nin += k; + s.nin += k; + k = footer(begin, s.nin, sum, nout, nin - s.nin - headerlen); + if (k == FlateErr) { + s.err = "footer error."; + n = FlateErr; + } else { + footerlen = k; + extralen = s.nin - k; + } + case FlateErr: + free(begin); + free(s.out); + err = s.err; + return n; + case FlateIn: + s.in = begin; + s.nin = fread(s.in, 1, Nin, in); + nin += s.nin; + break; + case FlateOut: + k = fwrite(s.out, 1, s.nout, out); + if (k != s.nout) + s.err = "write error."; + sum = checksum(s.out, k, sum); + nout += k; + s.nout = Nout; + break; + } +} + +static int old_main(int argc, char *argv[]) { + char comp = 'c'; + char fmt = 'r'; + char verbose = 'q'; + int (*call)(FILE *, FILE*); + int n, i; + + for (i = 1; i < argc; i++) { + if (argv[i][0] == '-' && argv[i][1] && argv[i][2] == 0) + switch (argv[i][1]) { + case 'q': + case 'v': + verbose = argv[i][1]; + continue; + case 'c': + case 'd': + comp = argv[i][1]; + continue; + case 'r': + case 'g': + case 'z': + case 'p': + fmt = argv[i][1]; + continue; + } + fprintf(stderr, "usage: %s [-q|-v] [-c|-d] [-r|-g|-z|-p]\n\n" + "deflate stream compression\n" + " -q quiet (default)\n" + " -v verbose\n" + " -c compress (default)\n" + " -d decompress\n" + " -r raw (default)\n" + " -g gzip\n" + " -z zlib\n" + " -p pkzip\n", argv[0]); + return -1; + } + call = comp == 'c' ? compress_stream : decompress_stream; + switch (fmt) { + case 'r': + header = dummyheader; + footer = dummyfooter; + checksum = dummysum; + n = call(stdin, stdout); + break; + case 'g': + if (comp == 'c') { + header = deflate_gzip_header; + footer = deflate_gzip_footer; + } else { + header = inflate_gzip_header; + footer = inflate_gzip_footer; + } + checksum = crc32; + crc32init(); + n = call(stdin, stdout); + break; + case 'z': + if (comp == 'c') { + header = deflate_zlib_header; + footer = deflate_zlib_footer; + } else { + header = inflate_zlib_header; + footer = inflate_zlib_footer; + } + checksum = adler32; + n = call(stdin, stdout); + break; + case 'p': + if (comp == 'c') { + header = deflate_pkzip_header; + footer = deflate_pkzip_footer; + } else { + header = inflate_pkzip_header; + footer = inflate_pkzip_footer; + } + checksum = crc32; + crc32init(); + n = call(stdin, stdout); + break; + default: + err = "uninplemented."; + n = FlateErr; + break; + } + if (verbose == 'v') + fprintf(stderr, "in:%d out:%d checksum: 0x%08x (header:%d data:%d footer:%d extra input:%s)\n", + nin, nout, sum, headerlen, (comp == 'c' ? nout : nin) - headerlen - footerlen - extralen, + footerlen, extralen ? "yes" : "no"); + if (n != FlateOk) + fprintf(stderr, "error: %s\n", err); + return n; +} + +// Total hack +void gzip_main(void) +{ + int i; + + for (i=0; toys.argv[i]; i++); + old_main(i, toys.argv); +} + + |