diff options
Diffstat (limited to 'main/zlib/infcodes.c')
-rw-r--r-- | main/zlib/infcodes.c | 398 |
1 files changed, 195 insertions, 203 deletions
diff --git a/main/zlib/infcodes.c b/main/zlib/infcodes.c index d4e5ee9..de5c410 100644 --- a/main/zlib/infcodes.c +++ b/main/zlib/infcodes.c @@ -1,6 +1,6 @@ /* infcodes.c -- process literals and length/distance pairs * Copyright (C) 1995-1998 Mark Adler - * For conditions of distribution and use, see copyright notice in zlib.h + * For conditions of distribution and use, see copyright notice in zlib.h */ #include "zutil.h" @@ -15,43 +15,44 @@ #define bits word.what.Bits typedef enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */ - START, /* x: set up for LEN */ - LEN, /* i: get length/literal/eob next */ - LENEXT, /* i: getting length extra (have base) */ - DIST, /* i: get distance next */ - DISTEXT, /* i: getting distance extra */ - COPY, /* o: copying bytes in window, waiting for space */ - LIT, /* o: got literal, waiting for output space */ - WASH, /* o: got eob, possibly still output waiting */ - END, /* x: got eob and all data flushed */ - BADCODE} /* x: got error */ + START, /* x: set up for LEN */ + LEN, /* i: get length/literal/eob next */ + LENEXT, /* i: getting length extra (have base) */ + DIST, /* i: get distance next */ + DISTEXT, /* i: getting distance extra */ + COPY, /* o: copying bytes in window, waiting for space */ + LIT, /* o: got literal, waiting for output space */ + WASH, /* o: got eob, possibly still output waiting */ + END, /* x: got eob and all data flushed */ + BADCODE +} /* x: got error */ inflate_codes_mode; /* inflate codes private state */ struct inflate_codes_state { - /* mode */ - inflate_codes_mode mode; /* current inflate_codes mode */ - - /* mode dependent information */ - uInt len; - union { - struct { - inflate_huft *tree; /* pointer into tree */ - uInt need; /* bits needed */ - } code; /* if LEN or DIST, where in tree */ - uInt lit; /* if LIT, literal */ - struct { - uInt get; /* bits to get for extra */ - uInt dist; /* distance back to copy from */ - } copy; /* if EXT or COPY, where and how much */ - } sub; /* submode */ - - /* mode independent information */ - Byte lbits; /* ltree bits decoded per branch */ - Byte dbits; /* dtree bits decoder per branch */ - inflate_huft *ltree; /* literal/length/eob tree */ - inflate_huft *dtree; /* distance tree */ + /* mode */ + inflate_codes_mode mode; /* current inflate_codes mode */ + + /* mode dependent information */ + uInt len; + union { + struct { + inflate_huft *tree; /* pointer into tree */ + uInt need; /* bits needed */ + } code; /* if LEN or DIST, where in tree */ + uInt lit; /* if LIT, literal */ + struct { + uInt get; /* bits to get for extra */ + uInt dist; /* distance back to copy from */ + } copy; /* if EXT or COPY, where and how much */ + } sub; /* submode */ + + /* mode independent information */ + Byte lbits; /* ltree bits decoded per branch */ + Byte dbits; /* dtree bits decoder per branch */ + inflate_huft *ltree; /* literal/length/eob tree */ + inflate_huft *dtree; /* distance tree */ }; @@ -62,19 +63,18 @@ inflate_huft *tl; inflate_huft *td; /* need separate declaration for Borland C++ */ z_streamp z; { - inflate_codes_statef *c; - - if ((c = (inflate_codes_statef *) - ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL) - { - c->mode = START; - c->lbits = (Byte)bl; - c->dbits = (Byte)bd; - c->ltree = tl; - c->dtree = td; - Tracev((stderr, "inflate: codes new\n")); - } - return c; + inflate_codes_statef *c; + + if((c = (inflate_codes_statef *) + ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL) { + c->mode = START; + c->lbits = (Byte)bl; + c->dbits = (Byte)bd; + c->ltree = tl; + c->dtree = td; + Tracev((stderr, "inflate: codes new\n")); + } + return c; } @@ -83,167 +83,159 @@ inflate_blocks_statef *s; z_streamp z; int r; { - uInt j; /* temporary storage */ - inflate_huft *t; /* temporary pointer */ - uInt e; /* extra bits or operation */ - uLong b; /* bit buffer */ - uInt k; /* bits in bit buffer */ - Bytef *p; /* input data pointer */ - uInt n; /* bytes available there */ - Bytef *q; /* output window write pointer */ - uInt m; /* bytes to end of window or read pointer */ - Bytef *f; /* pointer to copy strings from */ - inflate_codes_statef *c = s->sub.decode.codes; /* codes state */ - - /* copy input/output information to locals (UPDATE macro restores) */ - LOAD - - /* process input and output based on current state */ - while (1) switch (c->mode) - { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */ - case START: /* x: set up for LEN */ + uInt j; /* temporary storage */ + inflate_huft *t; /* temporary pointer */ + uInt e; /* extra bits or operation */ + uLong b; /* bit buffer */ + uInt k; /* bits in bit buffer */ + Bytef *p; /* input data pointer */ + uInt n; /* bytes available there */ + Bytef *q; /* output window write pointer */ + uInt m; /* bytes to end of window or read pointer */ + Bytef *f; /* pointer to copy strings from */ + inflate_codes_statef *c = s->sub.decode.codes; /* codes state */ + + /* copy input/output information to locals (UPDATE macro restores) */ + LOAD + + /* process input and output based on current state */ + while(1) switch(c->mode) { + /* waiting for "i:"=input, "o:"=output, "x:"=nothing */ + case START: /* x: set up for LEN */ #ifndef SLOW - if (m >= 258 && n >= 10) - { - UPDATE - r = inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z); - LOAD - if (r != Z_OK) - { - c->mode = r == Z_STREAM_END ? WASH : BADCODE; - break; - } - } + if(m >= 258 && n >= 10) { + UPDATE + r = inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z); + LOAD + if(r != Z_OK) { + c->mode = r == Z_STREAM_END ? WASH : BADCODE; + break; + } + } #endif /* !SLOW */ - c->sub.code.need = c->lbits; - c->sub.code.tree = c->ltree; - c->mode = LEN; - case LEN: /* i: get length/literal/eob next */ - j = c->sub.code.need; - NEEDBITS(j) - t = c->sub.code.tree + ((uInt)b & inflate_mask[j]); - DUMPBITS(t->bits) - e = (uInt)(t->exop); - if (e == 0) /* literal */ - { - c->sub.lit = t->base; - Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ? - "inflate: literal '%c'\n" : - "inflate: literal 0x%02x\n", t->base)); - c->mode = LIT; - break; - } - if (e & 16) /* length */ - { - c->sub.copy.get = e & 15; - c->len = t->base; - c->mode = LENEXT; - break; - } - if ((e & 64) == 0) /* next table */ - { - c->sub.code.need = e; - c->sub.code.tree = t + t->base; - break; - } - if (e & 32) /* end of block */ - { - Tracevv((stderr, "inflate: end of block\n")); - c->mode = WASH; - break; - } - c->mode = BADCODE; /* invalid code */ - z->msg = (char*)"invalid literal/length code"; - r = Z_DATA_ERROR; - LEAVE - case LENEXT: /* i: getting length extra (have base) */ - j = c->sub.copy.get; - NEEDBITS(j) - c->len += (uInt)b & inflate_mask[j]; - DUMPBITS(j) - c->sub.code.need = c->dbits; - c->sub.code.tree = c->dtree; - Tracevv((stderr, "inflate: length %u\n", c->len)); - c->mode = DIST; - case DIST: /* i: get distance next */ - j = c->sub.code.need; - NEEDBITS(j) - t = c->sub.code.tree + ((uInt)b & inflate_mask[j]); - DUMPBITS(t->bits) - e = (uInt)(t->exop); - if (e & 16) /* distance */ - { - c->sub.copy.get = e & 15; - c->sub.copy.dist = t->base; - c->mode = DISTEXT; - break; - } - if ((e & 64) == 0) /* next table */ - { - c->sub.code.need = e; - c->sub.code.tree = t + t->base; - break; - } - c->mode = BADCODE; /* invalid code */ - z->msg = (char*)"invalid distance code"; - r = Z_DATA_ERROR; - LEAVE - case DISTEXT: /* i: getting distance extra */ - j = c->sub.copy.get; - NEEDBITS(j) - c->sub.copy.dist += (uInt)b & inflate_mask[j]; - DUMPBITS(j) - Tracevv((stderr, "inflate: distance %u\n", c->sub.copy.dist)); - c->mode = COPY; - case COPY: /* o: copying bytes in window, waiting for space */ + c->sub.code.need = c->lbits; + c->sub.code.tree = c->ltree; + c->mode = LEN; + case LEN: /* i: get length/literal/eob next */ + j = c->sub.code.need; + NEEDBITS(j) + t = c->sub.code.tree + ((uInt)b & inflate_mask[j]); + DUMPBITS(t->bits) + e = (uInt)(t->exop); + if(e == 0) { /* literal */ + c->sub.lit = t->base; + Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ? + "inflate: literal '%c'\n" : + "inflate: literal 0x%02x\n", t->base)); + c->mode = LIT; + break; + } + if(e & 16) { /* length */ + c->sub.copy.get = e & 15; + c->len = t->base; + c->mode = LENEXT; + break; + } + if((e & 64) == 0) { /* next table */ + c->sub.code.need = e; + c->sub.code.tree = t + t->base; + break; + } + if(e & 32) { /* end of block */ + Tracevv((stderr, "inflate: end of block\n")); + c->mode = WASH; + break; + } + c->mode = BADCODE; /* invalid code */ + z->msg = (char *)"invalid literal/length code"; + r = Z_DATA_ERROR; + LEAVE + case LENEXT: /* i: getting length extra (have base) */ + j = c->sub.copy.get; + NEEDBITS(j) + c->len += (uInt)b & inflate_mask[j]; + DUMPBITS(j) + c->sub.code.need = c->dbits; + c->sub.code.tree = c->dtree; + Tracevv((stderr, "inflate: length %u\n", c->len)); + c->mode = DIST; + case DIST: /* i: get distance next */ + j = c->sub.code.need; + NEEDBITS(j) + t = c->sub.code.tree + ((uInt)b & inflate_mask[j]); + DUMPBITS(t->bits) + e = (uInt)(t->exop); + if(e & 16) { /* distance */ + c->sub.copy.get = e & 15; + c->sub.copy.dist = t->base; + c->mode = DISTEXT; + break; + } + if((e & 64) == 0) { /* next table */ + c->sub.code.need = e; + c->sub.code.tree = t + t->base; + break; + } + c->mode = BADCODE; /* invalid code */ + z->msg = (char *)"invalid distance code"; + r = Z_DATA_ERROR; + LEAVE + case DISTEXT: /* i: getting distance extra */ + j = c->sub.copy.get; + NEEDBITS(j) + c->sub.copy.dist += (uInt)b & inflate_mask[j]; + DUMPBITS(j) + Tracevv((stderr, "inflate: distance %u\n", c->sub.copy.dist)); + c->mode = COPY; + case COPY: /* o: copying bytes in window, waiting for space */ #ifndef __TURBOC__ /* Turbo C bug for following expression */ - f = (uInt)(q - s->window) < c->sub.copy.dist ? - s->end - (c->sub.copy.dist - (q - s->window)) : - q - c->sub.copy.dist; + f = (uInt)(q - s->window) < c->sub.copy.dist ? + s->end - (c->sub.copy.dist - (q - s->window)) : + q - c->sub.copy.dist; #else - f = q - c->sub.copy.dist; - if ((uInt)(q - s->window) < c->sub.copy.dist) - f = s->end - (c->sub.copy.dist - (uInt)(q - s->window)); + f = q - c->sub.copy.dist; + if((uInt)(q - s->window) < c->sub.copy.dist) { + f = s->end - (c->sub.copy.dist - (uInt)(q - s->window)); + } #endif - while (c->len) - { - NEEDOUT - OUTBYTE(*f++) - if (f == s->end) - f = s->window; - c->len--; - } - c->mode = START; - break; - case LIT: /* o: got literal, waiting for output space */ - NEEDOUT - OUTBYTE(c->sub.lit) - c->mode = START; - break; - case WASH: /* o: got eob, possibly more output */ - if (k > 7) /* return unused byte, if any */ - { - Assert(k < 16, "inflate_codes grabbed too many bytes") - k -= 8; - n++; - p--; /* can always return one */ - } - FLUSH - if (s->read != s->write) - LEAVE - c->mode = END; - case END: - r = Z_STREAM_END; - LEAVE - case BADCODE: /* x: got error */ - r = Z_DATA_ERROR; - LEAVE - default: - r = Z_STREAM_ERROR; - LEAVE - } + while(c->len) { + NEEDOUT + OUTBYTE(*f++) + if(f == s->end) { + f = s->window; + } + c->len--; + } + c->mode = START; + break; + case LIT: /* o: got literal, waiting for output space */ + NEEDOUT + OUTBYTE(c->sub.lit) + c->mode = START; + break; + case WASH: /* o: got eob, possibly more output */ + if(k > 7) { /* return unused byte, if any */ + Assert(k < 16, "inflate_codes grabbed too many bytes") + k -= 8; + n++; + p--; /* can always return one */ + } + FLUSH + if(s->read != s->write) + LEAVE + c->mode = END; + case END: + r = Z_STREAM_END; + LEAVE + case BADCODE: /* x: got error */ + r = Z_DATA_ERROR; + LEAVE + default: + r = Z_STREAM_ERROR; + LEAVE + } #ifdef NEED_DUMMY_RETURN - return Z_STREAM_ERROR; /* Some dumb compilers complain without this */ + return Z_STREAM_ERROR; /* Some dumb compilers complain without this */ #endif } @@ -252,6 +244,6 @@ void inflate_codes_free(c, z) inflate_codes_statef *c; z_streamp z; { - ZFREE(z, c); - Tracev((stderr, "inflate: codes free\n")); + ZFREE(z, c); + Tracev((stderr, "inflate: codes free\n")); } |