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zlib 1.2.3.4

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This commit is contained in:
Mark Adler
2011-09-09 23:26:40 -07:00
parent 639be99788
commit f6194ef39a
45 changed files with 3663 additions and 873 deletions
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195
contrib/puff/puff.c
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@@ -1,8 +1,8 @@
/*
* puff.c
* Copyright (C) 2002-2004 Mark Adler
* Copyright (C) 2002-2008 Mark Adler
* For conditions of distribution and use, see copyright notice in puff.h
* version 1.8, 9 Jan 2004
* version 2.0, 25 Jul 2008
*
* puff.c is a simple inflate written to be an unambiguous way to specify the
* deflate format. It is not written for speed but rather simplicity. As a
@@ -61,6 +61,12 @@
* 1.7 3 Mar 2003 - Added test code for distribution
* - Added zlib-like license
* 1.8 9 Jan 2004 - Added some comments on no distance codes case
* 1.9 21 Feb 2008 - Fix bug on 16-bit integer architectures [Pohland]
* - Catch missing end-of-block symbol error
* 2.0 25 Jul 2008 - Add #define to permit distance too far back
* - Add option in TEST code for puff to write the data
* - Add option in TEST code to skip input bytes
* - Allow TEST code to read from piped stdin
*/
#include <setjmp.h> /* for setjmp(), longjmp(), and jmp_buf */
@@ -194,7 +200,7 @@ struct huffman {
* Decode a code from the stream s using huffman table h. Return the symbol or
* a negative value if there is an error. If all of the lengths are zero, i.e.
* an empty code, or if the code is incomplete and an invalid code is received,
* then -9 is returned after reading MAXBITS bits.
* then -10 is returned after reading MAXBITS bits.
*
* Format notes:
*
@@ -226,14 +232,14 @@ local int decode(struct state *s, struct huffman *h)
for (len = 1; len <= MAXBITS; len++) {
code |= bits(s, 1); /* get next bit */
count = h->count[len];
if (code < first + count) /* if length len, return symbol */
if (code - count < first) /* if length len, return symbol */
return h->symbol[index + (code - first)];
index += count; /* else update for next length */
first += count;
first <<= 1;
code <<= 1;
}
return -9; /* ran out of codes */
return -10; /* ran out of codes */
}
/*
@@ -263,7 +269,7 @@ local int decode(struct state *s, struct huffman *h)
code |= bitbuf & 1;
bitbuf >>= 1;
count = *next++;
if (code < first + count) { /* if length len, return symbol */
if (code - count < first) { /* if length len, return symbol */
s->bitbuf = bitbuf;
s->bitcnt = (s->bitcnt - len) & 7;
return h->symbol[index + (code - first)];
@@ -280,7 +286,7 @@ local int decode(struct state *s, struct huffman *h)
bitbuf = s->in[s->incnt++];
if (left > 8) left = 8;
}
return -9; /* ran out of codes */
return -10; /* ran out of codes */
}
#endif /* SLOW */
@@ -448,21 +454,27 @@ local int codes(struct state *s,
else if (symbol > 256) { /* length */
/* get and compute length */
symbol -= 257;
if (symbol >= 29) return -9; /* invalid fixed code */
if (symbol >= 29) return -10; /* invalid fixed code */
len = lens[symbol] + bits(s, lext[symbol]);
/* get and check distance */
symbol = decode(s, distcode);
if (symbol < 0) return symbol; /* invalid symbol */
dist = dists[symbol] + bits(s, dext[symbol]);
#ifndef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR
if (dist > s->outcnt)
return -10; /* distance too far back */
return -11; /* distance too far back */
#endif
/* copy length bytes from distance bytes back */
if (s->out != NIL) {
if (s->outcnt + len > s->outlen) return 1;
while (len--) {
s->out[s->outcnt] = s->out[s->outcnt - dist];
s->out[s->outcnt] =
#ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR
dist > s->outcnt ? 0 :
#endif
s->out[s->outcnt - dist];
s->outcnt++;
}
}
@@ -680,6 +692,10 @@ local int dynamic(struct state *s)
}
}
/* check for end-of-block code -- there better be one! */
if (lengths[256] == 0)
return -9;
/* build huffman table for literal/length codes */
err = construct(&lencode, lengths, nlen);
if (err < 0 || (err > 0 && nlen - lencode.count[0] != 1))
@@ -724,8 +740,9 @@ local int dynamic(struct state *s)
* -6: dynamic block code description: repeat more than specified lengths
* -7: dynamic block code description: invalid literal/length code lengths
* -8: dynamic block code description: invalid distance code lengths
* -9: invalid literal/length or distance code in fixed or dynamic block
* -10: distance is too far back in fixed or dynamic block
* -9: dynamic block code description: missing end-of-block code
* -10: invalid literal/length or distance code in fixed or dynamic block
* -11: distance is too far back in fixed or dynamic block
*
* Format notes:
*
@@ -783,54 +800,142 @@ int puff(unsigned char *dest, /* pointer to destination pointer */
}
#ifdef TEST
/* Example of how to use puff() */
/* Examples of how to use puff().
Usage: puff [-w] [-nnn] file
... | puff [-w] [-nnn]
where file is the input file with deflate data, nnn is the number of bytes
of input to skip before inflating (e.g. to skip a zlib or gzip header), and
-w is used to write the decompressed data to stdout */
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
local unsigned char *yank(char *name, unsigned long *len)
/* Return size times approximately the cube root of 2, keeping the result as 1,
3, or 5 times a power of 2 -- the result is always > size, until the result
is the maximum value of an unsigned long, where it remains. This is useful
to keep reallocations less than ~33% over the actual data. */
local size_t bythirds(size_t size)
{
unsigned long size;
unsigned char *buf;
int n;
size_t m;
m = size;
for (n = 0; m; n++)
m >>= 1;
if (n < 3)
return size + 1;
n -= 3;
m = size >> n;
m += m == 6 ? 2 : 1;
m <<= n;
return m > size ? m : (size_t)(-1);
}
/* Read the input file *name, or stdin if name is NULL, into allocated memory.
Reallocate to larger buffers until the entire file is read in. Return a
pointer to the allocated data, or NULL if there was a memory allocation
failure. *len is the number of bytes of data read from the input file (even
if load() returns NULL). If the input file was empty or could not be opened
or read, *len is zero. */
local void *load(char *name, size_t *len)
{
size_t size;
void *buf, *swap;
FILE *in;
struct stat s;
*len = 0;
if (stat(name, &s)) return NULL;
if ((s.st_mode & S_IFMT) != S_IFREG) return NULL;
size = (unsigned long)(s.st_size);
if (size == 0 || (off_t)size != s.st_size) return NULL;
in = fopen(name, "r");
if (in == NULL) return NULL;
buf = malloc(size);
if (buf != NULL && fread(buf, 1, size, in) != size) {
free(buf);
buf = NULL;
buf = malloc(size = 4096);
if (buf == NULL)
return NULL;
in = name == NULL ? stdin : fopen(name, "rb");
if (in != NULL) {
for (;;) {
*len += fread((char *)buf + *len, 1, size - *len, in);
if (*len < size) break;
size = bythirds(size);
if (size == *len || (swap = realloc(buf, size)) == NULL) {
free(buf);
buf = NULL;
break;
}
buf = swap;
}
fclose(in);
}
fclose(in);
*len = size;
return buf;
}
int main(int argc, char **argv)
{
int ret;
unsigned char *source;
unsigned long len, sourcelen, destlen;
int ret, skip = 0, put = 0;
char *arg, *name = NULL;
unsigned char *source = NULL, *dest;
size_t len = 0;
unsigned long sourcelen, destlen;
if (argc < 2) return 2;
source = yank(argv[1], &len);
if (source == NULL) return 2;
sourcelen = len;
ret = puff(NIL, &destlen, source, &sourcelen);
if (ret)
printf("puff() failed with return code %d\n", ret);
else {
printf("puff() succeeded uncompressing %lu bytes\n", destlen);
if (sourcelen < len) printf("%lu compressed bytes unused\n",
len - sourcelen);
/* process arguments */
while (arg = *++argv, --argc)
if (arg[0] == '-') {
if (arg[1] == 'w' && arg[2] == 0)
put = 1;
else if (arg[1] >= '0' && arg[1] <= '9')
skip = atoi(arg + 1);
else {
fprintf(stderr, "invalid option %s\n", arg);
return 3;
}
}
else if (name != NULL) {
fprintf(stderr, "only one file name allowed\n");
return 3;
}
else
name = arg;
source = load(name, &len);
if (source == NULL) {
fprintf(stderr, "memory allocation failure\n");
return 4;
}
if (len == 0) {
fprintf(stderr, "could not read %s, or it was empty\n",
name == NULL ? "<stdin>" : name);
free(source);
return 3;
}
if (skip >= len) {
fprintf(stderr, "skip request of %d leaves no input\n", skip);
free(source);
return 3;
}
/* test inflate data with offset skip */
len -= skip;
sourcelen = (unsigned long)len;
ret = puff(NIL, &destlen, source + skip, &sourcelen);
if (ret)
fprintf(stderr, "puff() failed with return code %d\n", ret);
else {
fprintf(stderr, "puff() succeeded uncompressing %lu bytes\n", destlen);
if (sourcelen < len) fprintf(stderr, "%lu compressed bytes unused\n",
len - sourcelen);
}
/* if requested, inflate again and write decompressd data to stdout */
if (put) {
dest = malloc(destlen);
if (dest == NULL) {
fprintf(stderr, "memory allocation failure\n");
free(source);
return 4;
}
puff(dest, &destlen, source + skip, &sourcelen);
fwrite(dest, 1, destlen, stdout);
free(dest);
}
/* clean up */
free(source);
return ret;
}