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zlib 1.2.0.5

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This commit is contained in:
Mark Adler
2011-09-09 23:22:37 -07:00
parent 086e982175
commit 4b5a43a219
152 changed files with 14540 additions and 12588 deletions
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154
contrib/blast/blast.c
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@@ -20,36 +20,36 @@
/*
* Change history:
*
* 1.0 12 Feb 2003 - First version
* 1.1 16 Feb 2003 - Fixed distance check for > 4 GB uncompressed data
* 1.0 12 Feb 2003 - First version
* 1.1 16 Feb 2003 - Fixed distance check for > 4 GB uncompressed data
*/
#include <setjmp.h> /* for setjmp(), longjmp(), and jmp_buf */
#include "blast.h" /* prototype for blast() */
#include <setjmp.h> /* for setjmp(), longjmp(), and jmp_buf */
#include "blast.h" /* prototype for blast() */
#define local static /* for local function definitions */
#define MAXBITS 13 /* maximum code length */
#define MAXWIN 4096 /* maximum window size */
#define local static /* for local function definitions */
#define MAXBITS 13 /* maximum code length */
#define MAXWIN 4096 /* maximum window size */
/* input and output state */
struct state {
/* input state */
blast_in infun; /* input function provided by user */
void *inhow; /* opaque information passed to infun() */
unsigned char *in; /* next input location */
unsigned left; /* available input at in */
int bitbuf; /* bit buffer */
int bitcnt; /* number of bits in bit buffer */
blast_in infun; /* input function provided by user */
void *inhow; /* opaque information passed to infun() */
unsigned char *in; /* next input location */
unsigned left; /* available input at in */
int bitbuf; /* bit buffer */
int bitcnt; /* number of bits in bit buffer */
/* input limit error return state for bits() and decode() */
jmp_buf env;
/* output state */
blast_out outfun; /* output function provided by user */
void *outhow; /* opaque information passed to outfun() */
unsigned next; /* index of next write location in out[] */
int first; /* true to check distances (for first 4K) */
unsigned char out[MAXWIN]; /* output buffer and sliding window */
blast_out outfun; /* output function provided by user */
void *outhow; /* opaque information passed to outfun() */
unsigned next; /* index of next write location in out[] */
int first; /* true to check distances (for first 4K) */
unsigned char out[MAXWIN]; /* output buffer and sliding window */
};
/*
@@ -65,16 +65,16 @@ struct state {
*/
local int bits(struct state *s, int need)
{
int val; /* bit accumulator */
int val; /* bit accumulator */
/* load at least need bits into val */
val = s->bitbuf;
while (s->bitcnt < need) {
if (s->left == 0) {
s->left = s->infun(s->inhow, &(s->in));
if (s->left == 0) longjmp(s->env, 1); /* out of input */
if (s->left == 0) longjmp(s->env, 1); /* out of input */
}
val |= (int)(*(s->in)++) << s->bitcnt; /* load eight bits */
val |= (int)(*(s->in)++) << s->bitcnt; /* load eight bits */
s->left--;
s->bitcnt += 8;
}
@@ -95,8 +95,8 @@ local int bits(struct state *s, int need)
* seen in the function decode() below.
*/
struct huffman {
short *count; /* number of symbols of each length */
short *symbol; /* canonically ordered symbols */
short *count; /* number of symbols of each length */
short *symbol; /* canonically ordered symbols */
};
/*
@@ -122,14 +122,14 @@ struct huffman {
*/
local int decode(struct state *s, struct huffman *h)
{
int len; /* current number of bits in code */
int code; /* len bits being decoded */
int first; /* first code of length len */
int count; /* number of codes of length len */
int index; /* index of first code of length len in symbol table */
int bitbuf; /* bits from stream */
int left; /* bits left in next or left to process */
short *next; /* next number of codes */
int len; /* current number of bits in code */
int code; /* len bits being decoded */
int first; /* first code of length len */
int count; /* number of codes of length len */
int index; /* index of first code of length len in symbol table */
int bitbuf; /* bits from stream */
int left; /* bits left in next or left to process */
short *next; /* next number of codes */
bitbuf = s->bitbuf;
left = s->bitcnt;
@@ -138,15 +138,15 @@ local int decode(struct state *s, struct huffman *h)
next = h->count + 1;
while (1) {
while (left--) {
code |= (bitbuf & 1) ^ 1; /* invert code */
code |= (bitbuf & 1) ^ 1; /* invert code */
bitbuf >>= 1;
count = *next++;
if (code < first + count) { /* if length len, return symbol */
if (code < first + count) { /* if length len, return symbol */
s->bitbuf = bitbuf;
s->bitcnt = (s->bitcnt - len) & 7;
return h->symbol[index + (code - first)];
}
index += count; /* else update for next length */
index += count; /* else update for next length */
first += count;
first <<= 1;
code <<= 1;
@@ -156,13 +156,13 @@ local int decode(struct state *s, struct huffman *h)
if (left == 0) break;
if (s->left == 0) {
s->left = s->infun(s->inhow, &(s->in));
if (s->left == 0) longjmp(s->env, 1); /* out of input */
if (s->left == 0) longjmp(s->env, 1); /* out of input */
}
bitbuf = *(s->in)++;
s->left--;
if (left > 8) left = 8;
}
return -9; /* ran out of codes */
return -9; /* ran out of codes */
}
/*
@@ -184,11 +184,11 @@ local int decode(struct state *s, struct huffman *h)
*/
local int construct(struct huffman *h, const unsigned char *rep, int n)
{
int symbol; /* current symbol when stepping through length[] */
int len; /* current length when stepping through h->count[] */
int left; /* number of possible codes left of current length */
short offs[MAXBITS+1]; /* offsets in symbol table for each length */
short length[256]; /* code lengths */
int symbol; /* current symbol when stepping through length[] */
int len; /* current length when stepping through h->count[] */
int left; /* number of possible codes left of current length */
short offs[MAXBITS+1]; /* offsets in symbol table for each length */
short length[256]; /* code lengths */
/* convert compact repeat counts into symbol bit length list */
symbol = 0;
@@ -206,17 +206,17 @@ local int construct(struct huffman *h, const unsigned char *rep, int n)
for (len = 0; len <= MAXBITS; len++)
h->count[len] = 0;
for (symbol = 0; symbol < n; symbol++)
(h->count[length[symbol]])++; /* assumes lengths are within bounds */
if (h->count[0] == n) /* no codes! */
return 0; /* complete, but decode() will fail */
(h->count[length[symbol]])++; /* assumes lengths are within bounds */
if (h->count[0] == n) /* no codes! */
return 0; /* complete, but decode() will fail */
/* check for an over-subscribed or incomplete set of lengths */
left = 1; /* one possible code of zero length */
left = 1; /* one possible code of zero length */
for (len = 1; len <= MAXBITS; len++) {
left <<= 1; /* one more bit, double codes left */
left -= h->count[len]; /* deduct count from possible codes */
if (left < 0) return left; /* over-subscribed--return negative */
} /* left > 0 means incomplete */
left <<= 1; /* one more bit, double codes left */
left -= h->count[len]; /* deduct count from possible codes */
if (left < 0) return left; /* over-subscribed--return negative */
} /* left > 0 means incomplete */
/* generate offsets into symbol table for each length for sorting */
offs[1] = 0;
@@ -275,35 +275,35 @@ local int construct(struct huffman *h, const unsigned char *rep, int n)
*/
local int decomp(struct state *s)
{
int lit; /* true if literals are coded */
int dict; /* log2(dictionary size) - 6 */
int symbol; /* decoded symbol, extra bits for distance */
int len; /* length for copy */
int dist; /* distance for copy */
int copy; /* copy counter */
unsigned char *from, *to; /* copy pointers */
static int virgin = 1; /* build tables once */
static short litcnt[MAXBITS+1], litsym[256]; /* litcode memory */
static short lencnt[MAXBITS+1], lensym[16]; /* lencode memory */
static short distcnt[MAXBITS+1], distsym[64]; /* distcode memory */
static struct huffman litcode = {litcnt, litsym}; /* length code */
static struct huffman lencode = {lencnt, lensym}; /* length code */
int lit; /* true if literals are coded */
int dict; /* log2(dictionary size) - 6 */
int symbol; /* decoded symbol, extra bits for distance */
int len; /* length for copy */
int dist; /* distance for copy */
int copy; /* copy counter */
unsigned char *from, *to; /* copy pointers */
static int virgin = 1; /* build tables once */
static short litcnt[MAXBITS+1], litsym[256]; /* litcode memory */
static short lencnt[MAXBITS+1], lensym[16]; /* lencode memory */
static short distcnt[MAXBITS+1], distsym[64]; /* distcode memory */
static struct huffman litcode = {litcnt, litsym}; /* length code */
static struct huffman lencode = {lencnt, lensym}; /* length code */
static struct huffman distcode = {distcnt, distsym};/* distance code */
/* bit lengths of literal codes */
static const unsigned char litlen[] = {
11, 124, 8, 7, 28, 7, 188, 13, 76, 4, 10, 8, 12, 10, 12, 10, 8, 23, 8,
9, 7, 6, 7, 8, 7, 6, 55, 8, 23, 24, 12, 11, 7, 9, 11, 12, 6, 7, 22, 5,
7, 24, 6, 11, 9, 6, 7, 22, 7, 11, 38, 7, 9, 8, 25, 11, 8, 11, 9, 12,
8, 12, 5, 38, 5, 38, 5, 11, 7, 5, 6, 21, 6, 10, 53, 8, 7, 24, 10, 27,
44, 253, 253, 253, 252, 252, 252, 13, 12, 45, 12, 45, 12, 61, 12, 45,
44, 173};
11, 124, 8, 7, 28, 7, 188, 13, 76, 4, 10, 8, 12, 10, 12, 10, 8, 23, 8,
9, 7, 6, 7, 8, 7, 6, 55, 8, 23, 24, 12, 11, 7, 9, 11, 12, 6, 7, 22, 5,
7, 24, 6, 11, 9, 6, 7, 22, 7, 11, 38, 7, 9, 8, 25, 11, 8, 11, 9, 12,
8, 12, 5, 38, 5, 38, 5, 11, 7, 5, 6, 21, 6, 10, 53, 8, 7, 24, 10, 27,
44, 253, 253, 253, 252, 252, 252, 13, 12, 45, 12, 45, 12, 61, 12, 45,
44, 173};
/* bit lengths of length codes 0..15 */
static const unsigned char lenlen[] = {2, 35, 36, 53, 38, 23};
/* bit lengths of distance codes 0..63 */
static const unsigned char distlen[] = {2, 20, 53, 230, 247, 151, 248};
static const short base[16] = { /* base for length codes */
static const short base[16] = { /* base for length codes */
3, 2, 4, 5, 6, 7, 8, 9, 10, 12, 16, 24, 40, 72, 136, 264};
static const char extra[16] = { /* extra bits for length codes */
static const char extra[16] = { /* extra bits for length codes */
0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8};
/* set up decoding tables (once--might not be thread-safe) */
@@ -326,7 +326,7 @@ local int decomp(struct state *s)
/* get length */
symbol = decode(s, &lencode);
len = base[symbol] + bits(s, extra[symbol]);
if (len == 519) break; /* end code */
if (len == 519) break; /* end code */
/* get distance */
symbol = len == 2 ? 2 : dict;
@@ -334,7 +334,7 @@ local int decomp(struct state *s)
dist += bits(s, symbol);
dist++;
if (s->first && dist > s->next)
return -3; /* distance too far back */
return -3; /* distance too far back */
/* copy length bytes from distance bytes back */
do {
@@ -376,8 +376,8 @@ local int decomp(struct state *s)
/* See comments in blast.h */
int blast(blast_in infun, void *inhow, blast_out outfun, void *outhow)
{
struct state s; /* input/output state */
int err; /* return value */
struct state s; /* input/output state */
int err; /* return value */
/* initialize input state */
s.infun = infun;
@@ -393,10 +393,10 @@ int blast(blast_in infun, void *inhow, blast_out outfun, void *outhow)
s.first = 1;
/* return if bits() or decode() tries to read past available input */
if (setjmp(s.env) != 0) /* if came back here via longjmp(), */
err = 2; /* then skip decomp(), return error */
if (setjmp(s.env) != 0) /* if came back here via longjmp(), */
err = 2; /* then skip decomp(), return error */
else
err = decomp(&s); /* decompress */
err = decomp(&s); /* decompress */
/* write any leftover output and update the error code if needed */
if (err != 1 && s.next && s.outfun(s.outhow, s.out, s.next) && err == 0)