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zlib 1.0-pre

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This commit is contained in:
Mark Adler
2011-09-09 23:13:27 -07:00
parent 56bcb184fa
commit 8a2acbffc8
32 changed files with 588 additions and 1274 deletions
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361
gzio.c
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@@ -1,5 +1,5 @@
/* gzio.c -- IO on .gz files
* Copyright (C) 1995-1996 Jean-loup Gailly.
* Copyright (C) 1995 Jean-loup Gailly.
* For conditions of distribution and use, see copyright notice in zlib.h
*/
@@ -16,7 +16,8 @@ struct internal_state {int dummy;}; /* for buggy compilers */
#define ALLOC(size) malloc(size)
#define TRYFREE(p) {if (p) free(p);}
static int gz_magic[2] = {0x1f, 0x8b}; /* gzip magic header */
#define GZ_MAGIC_1 0x1f
#define GZ_MAGIC_2 0x8b
/* gzip flag byte */
#define ASCII_FLAG 0x01 /* bit 0 set: file probably ascii text */
@@ -26,6 +27,10 @@ static int gz_magic[2] = {0x1f, 0x8b}; /* gzip magic header */
#define COMMENT 0x10 /* bit 4 set: file comment present */
#define RESERVED 0xE0 /* bits 5..7: reserved */
#ifndef SEEK_CUR
# define SEEK_CUR 1
#endif
typedef struct gz_stream {
z_stream stream;
int z_err; /* error code for last stream operation */
@@ -41,12 +46,40 @@ typedef struct gz_stream {
} gz_stream;
local gzFile gz_open OF((const char *path, const char *mode, int fd));
local int get_byte OF((gz_stream *s));
local void check_header OF((gz_stream *s));
local int destroy OF((gz_stream *s));
local void putLong OF((FILE *file, uLong x));
local uLong getLong OF((gz_stream *s));
local int destroy OF((gz_stream *s));
local gzFile gz_open OF((char *path, char *mode, int fd));
local void putLong OF((FILE *file, uLong x));
local uLong getLong OF((Bytef *buf));
/* ===========================================================================
* Cleanup then free the given gz_stream. Return a zlib error code.
*/
local int destroy (s)
gz_stream *s;
{
int err = Z_OK;
if (!s) return Z_STREAM_ERROR;
TRYFREE(s->inbuf);
TRYFREE(s->outbuf);
TRYFREE(s->path);
TRYFREE(s->msg);
if (s->stream.state != NULL) {
if (s->mode == 'w') {
err = deflateEnd(&(s->stream));
} else if (s->mode == 'r') {
err = inflateEnd(&(s->stream));
}
}
if (s->file != NULL && fclose(s->file)) {
err = Z_ERRNO;
}
if (s->z_err < 0) err = s->z_err;
TRYFREE(s);
return err;
}
/* ===========================================================================
Opens a gzip (.gz) file for reading or writing. The mode parameter
@@ -58,20 +91,15 @@ local uLong getLong OF((gz_stream *s));
zlib error is Z_MEM_ERROR).
*/
local gzFile gz_open (path, mode, fd)
const char *path;
const char *mode;
char *path;
char *mode;
int fd;
{
int err;
int level = Z_DEFAULT_COMPRESSION; /* compression level */
char *p = (char*)mode;
gz_stream *s;
char fmode[80]; /* copy of mode, without the compression level */
char *m = fmode;
char *p = mode;
gz_stream *s = (gz_stream *)ALLOC(sizeof(gz_stream));
if (!path || !mode) return Z_NULL;
s = (gz_stream *)ALLOC(sizeof(gz_stream));
if (!s) return Z_NULL;
s->stream.zalloc = (alloc_func)0;
@@ -96,13 +124,9 @@ local gzFile gz_open (path, mode, fd)
s->mode = '\0';
do {
if (*p == 'r') s->mode = 'r';
if (*p == 'w' || *p == 'a') s->mode = 'w';
if (*p >= '0' && *p <= '9') {
level = *p - '0';
} else {
*m++ = *p; /* copy the mode */
}
} while (*p++ && m != fmode + sizeof(fmode));
if (*p == 'w') s->mode = 'w';
if (*p >= '1' && *p <= '9') level = *p - '0';
} while (*p++);
if (s->mode == '\0') return destroy(s), (gzFile)Z_NULL;
if (s->mode == 'w') {
@@ -126,7 +150,7 @@ local gzFile gz_open (path, mode, fd)
s->stream.avail_out = Z_BUFSIZE;
errno = 0;
s->file = fd < 0 ? FOPEN(path, fmode) : (FILE*)fdopen(fd, fmode);
s->file = fd < 0 ? FOPEN(path, mode) : (FILE*)fdopen(fd, mode);
if (s->file == NULL) {
return destroy(s), (gzFile)Z_NULL;
@@ -134,10 +158,50 @@ local gzFile gz_open (path, mode, fd)
if (s->mode == 'w') {
/* Write a very simple .gz header:
*/
fprintf(s->file, "%c%c%c%c%c%c%c%c%c%c", gz_magic[0], gz_magic[1],
fprintf(s->file, "%c%c%c%c%c%c%c%c%c%c", GZ_MAGIC_1, GZ_MAGIC_2,
Z_DEFLATED, 0 /*flags*/, 0,0,0,0 /*time*/, 0 /*xflags*/, OS_CODE);
} else {
check_header(s); /* skip the .gz header */
/* Check and skip the header:
*/
Byte c1 = 0, c2 = 0;
Byte method = 0;
Byte flags = 0;
Byte xflags = 0;
Byte time[4];
Byte osCode;
int c;
s->stream.avail_in = fread(s->inbuf, 1, 2, s->file);
if (s->stream.avail_in != 2 || s->inbuf[0] != GZ_MAGIC_1
|| s->inbuf[1] != GZ_MAGIC_2) {
s->transparent = 1;
return (gzFile)s;
}
s->stream.avail_in = 0;
fscanf(s->file,"%c%c%4c%c%c", &method, &flags, time, &xflags, &osCode);
if (method != Z_DEFLATED || feof(s->file) || (flags & RESERVED) != 0) {
s->z_err = Z_DATA_ERROR;
return (gzFile)s;
}
if ((flags & EXTRA_FIELD) != 0) { /* skip the extra field */
long len;
fscanf(s->file, "%c%c", &c1, &c2);
len = c1 + ((long)c2<<8);
fseek(s->file, len, SEEK_CUR);
}
if ((flags & ORIG_NAME) != 0) { /* skip the original file name */
while ((c = getc(s->file)) != 0 && c != EOF) ;
}
if ((flags & COMMENT) != 0) { /* skip the .gz file comment */
while ((c = getc(s->file)) != 0 && c != EOF) ;
}
if ((flags & HEAD_CRC) != 0) { /* skip the header crc */
fscanf(s->file, "%c%c", &c1, &c2);
}
if (feof(s->file)) {
s->z_err = Z_DATA_ERROR;
}
}
return (gzFile)s;
}
@@ -146,138 +210,25 @@ local gzFile gz_open (path, mode, fd)
Opens a gzip (.gz) file for reading or writing.
*/
gzFile gzopen (path, mode)
const char *path;
const char *mode;
char *path;
char *mode;
{
return gz_open (path, mode, -1);
}
/* ===========================================================================
Associate a gzFile with the file descriptor fd. fd is not dup'ed here
to mimic the behavio(u)r of fdopen.
Associate a gzFile with the file descriptor fd.
*/
gzFile gzdopen (fd, mode)
int fd;
const char *mode;
char *mode;
{
char name[20];
if (fd < 0) return (gzFile)Z_NULL;
sprintf(name, "<fd:%d>", fd); /* for debugging */
return gz_open (name, mode, fd);
}
/* ===========================================================================
Read a byte from a gz_stream; update next_in and avail_in. Return EOF
for end of file.
IN assertion: the stream s has been sucessfully opened for reading.
*/
local int get_byte(s)
gz_stream *s;
{
if (s->z_eof) return EOF;
if (s->stream.avail_in == 0) {
errno = 0;
s->stream.avail_in = fread(s->inbuf, 1, Z_BUFSIZE, s->file);
if (s->stream.avail_in == 0) {
s->z_eof = 1;
if (ferror(s->file)) s->z_err = Z_ERRNO;
return EOF;
}
s->stream.next_in = s->inbuf;
}
s->stream.avail_in--;
return *(s->stream.next_in)++;
}
/* ===========================================================================
Check the gzip header of a gz_stream opened for reading. Set the stream
mode to transparent if the gzip magic header is not present; set s->err
to Z_DATA_ERROR if the magic header is present but the rest of the header
is incorrect.
IN assertion: the stream s has already been created sucessfully;
s->stream.avail_in is zero for the first time, but may be non-zero
for concatenated .gz files.
*/
local void check_header(s)
gz_stream *s;
{
int method = 0;
int flags = 0;
uInt len;
int c;
/* Check the gzip magic header */
for (len = 0; len < 2; len++) {
c = get_byte(s);
if (c != gz_magic[len]) {
s->transparent = 1;
if (c != EOF) s->stream.avail_in++, s->stream.next_in--;
s->z_err = s->stream.avail_in != 0 ? Z_OK : Z_STREAM_END;
return;
}
}
method = get_byte(s);
flags = get_byte(s);
if (method != Z_DEFLATED || (flags & RESERVED) != 0) {
s->z_err = Z_DATA_ERROR;
return;
}
/* Discard time, xflags and OS code: */
for (len = 0; len < 6; len++) (void)get_byte(s);
if ((flags & EXTRA_FIELD) != 0) { /* skip the extra field */
len = (uInt)get_byte(s);
len += ((uInt)get_byte(s))<<8;
/* len is garbage if EOF but the loop below will quit anyway */
while (len-- != 0 && get_byte(s) != EOF) ;
}
if ((flags & ORIG_NAME) != 0) { /* skip the original file name */
while ((c = get_byte(s)) != 0 && c != EOF) ;
}
if ((flags & COMMENT) != 0) { /* skip the .gz file comment */
while ((c = get_byte(s)) != 0 && c != EOF) ;
}
if ((flags & HEAD_CRC) != 0) { /* skip the header crc */
for (len = 0; len < 2; len++) (void)get_byte(s);
}
s->z_err = s->z_eof ? Z_DATA_ERROR : Z_OK;
}
/* ===========================================================================
* Cleanup then free the given gz_stream. Return a zlib error code.
Try freeing in the reverse order of allocations.
*/
local int destroy (s)
gz_stream *s;
{
int err = Z_OK;
if (!s) return Z_STREAM_ERROR;
TRYFREE(s->msg);
if (s->stream.state != NULL) {
if (s->mode == 'w') {
err = deflateEnd(&(s->stream));
} else if (s->mode == 'r') {
err = inflateEnd(&(s->stream));
}
}
if (s->file != NULL && fclose(s->file)) {
err = Z_ERRNO;
}
if (s->z_err < 0) err = s->z_err;
TRYFREE(s->inbuf);
TRYFREE(s->outbuf);
TRYFREE(s->path);
TRYFREE(s);
return err;
}
/* ===========================================================================
Reads the given number of uncompressed bytes from the compressed file.
gzread returns the number of bytes actually read (0 for end of file).
@@ -288,71 +239,52 @@ int gzread (file, buf, len)
unsigned len;
{
gz_stream *s = (gz_stream*)file;
Byte *start = buf; /* starting point for crc computation */
if (s == NULL || s->mode != 'r') return Z_STREAM_ERROR;
if (s->z_err == Z_DATA_ERROR || s->z_err == Z_ERRNO) return -1;
if (s->z_err == Z_STREAM_END) return 0; /* EOF */
if (s->transparent) {
int n = 0;
Byte *b = (Byte*)buf;
/* Copy the first two (non-magic) bytes if not done already */
while (s->stream.avail_in > 0 && len > 0) {
*b++ = *s->stream.next_in++;
s->stream.avail_in--;
len--; n++;
}
if (len == 0) return n;
return n + fread(b, 1, len, s->file);
}
if (s->z_err == Z_DATA_ERROR) return -1; /* bad .gz file */
if (s->z_err == Z_STREAM_END) return 0; /* don't read crc as data */
s->stream.next_out = buf;
s->stream.avail_out = len;
while (s->stream.avail_out != 0) {
if (s->transparent) {
/* Copy first the lookahead bytes: */
uInt n = s->stream.avail_in;
if (n > s->stream.avail_out) n = s->stream.avail_out;
if (n > 0) {
zmemcpy(s->stream.next_out, s->stream.next_in, n);
s->stream.next_out += n;
s->stream.next_in += n;
s->stream.avail_out -= n;
s->stream.avail_in -= n;
}
if (s->stream.avail_out > 0) {
s->stream.avail_out -= fread(s->stream.next_out,
1, s->stream.avail_out, s->file);
}
return (int)(len - s->stream.avail_out);
}
if (s->stream.avail_in == 0 && !s->z_eof) {
errno = 0;
s->stream.avail_in = fread(s->inbuf, 1, Z_BUFSIZE, s->file);
s->stream.avail_in =
fread(s->inbuf, 1, Z_BUFSIZE, s->file);
if (s->stream.avail_in == 0) {
s->z_eof = 1;
if (ferror(s->file)) {
s->z_err = Z_ERRNO;
break;
}
} else if (s->stream.avail_in == (uInt)EOF) {
s->stream.avail_in = 0;
s->z_eof = 1;
s->z_err = Z_ERRNO;
break;
}
s->stream.next_in = s->inbuf;
}
s->z_err = inflate(&(s->stream), Z_NO_FLUSH);
if (s->z_err == Z_STREAM_END) {
/* Check CRC and original size */
s->crc = crc32(s->crc, start, (uInt)(s->stream.next_out - start));
start = s->stream.next_out;
if (getLong(s) != s->crc || getLong(s) != s->stream.total_out) {
s->z_err = Z_DATA_ERROR;
} else {
/* Check for concatenated .gz files: */
check_header(s);
if (s->z_err == Z_OK) {
inflateReset(&(s->stream));
s->crc = crc32(0L, Z_NULL, 0);
}
}
}
if (s->z_err != Z_OK || s->z_eof) break;
if (s->z_err == Z_STREAM_END ||
s->z_err != Z_OK || s->z_eof) break;
}
s->crc = crc32(s->crc, start, (uInt)(s->stream.next_out - start));
return (int)(len - s->stream.avail_out);
len -= s->stream.avail_out;
s->crc = crc32(s->crc, buf, len);
return (int)len;
}
/* ===========================================================================
@@ -361,7 +293,7 @@ int gzread (file, buf, len)
*/
int gzwrite (file, buf, len)
gzFile file;
const voidp buf;
voidp buf;
unsigned len;
{
gz_stream *s = (gz_stream*)file;
@@ -412,7 +344,7 @@ int gzflush (file, flush)
len = Z_BUFSIZE - s->stream.avail_out;
if (len != 0) {
if ((uInt)fwrite(s->outbuf, 1, len, s->file) != len) {
if (fwrite(s->outbuf, 1, len, s->file) != len) {
s->z_err = Z_ERRNO;
return Z_ERRNO;
}
@@ -448,19 +380,18 @@ local void putLong (file, x)
}
/* ===========================================================================
Reads a long in LSB order from the given gz_stream. Sets
Reads a long in LSB order from the given buffer
*/
local uLong getLong (s)
gz_stream *s;
local uLong getLong (buf)
Bytef *buf;
{
uLong x = (uLong)get_byte(s);
int c;
uLong x = 0;
Bytef *p = buf+4;
x += ((uLong)get_byte(s))<<8;
x += ((uLong)get_byte(s))<<16;
c = get_byte(s);
if (c == EOF) s->z_err = Z_DATA_ERROR;
x += ((uLong)c)<<24;
do {
x <<= 8;
x |= *--p;
} while (p != buf);
return x;
}
@@ -471,6 +402,7 @@ local uLong getLong (s)
int gzclose (file)
gzFile file;
{
uInt n;
int err;
gz_stream *s = (gz_stream*)file;
@@ -483,6 +415,25 @@ int gzclose (file)
putLong (s->file, s->crc);
putLong (s->file, s->stream.total_in);
} else if (s->mode == 'r' && s->z_err == Z_STREAM_END) {
/* slide CRC and original size if they are at the end of inbuf */
if ((n = s->stream.avail_in) < 8 && !s->z_eof) {
Byte *p = s->inbuf;
Bytef *q = s->stream.next_in;
while (n--) { *p++ = *q++; };
n = s->stream.avail_in;
n += fread(p, 1, 8, s->file);
s->stream.next_in = s->inbuf;
}
/* check CRC and original size */
if (n < 8 ||
getLong(s->stream.next_in) != s->crc ||
getLong(s->stream.next_in + 4) != s->stream.total_out) {
s->z_err = Z_DATA_ERROR;
}
}
return destroy(file);
}
@@ -503,14 +454,14 @@ char* gzerror (file, errnum)
if (s == NULL) {
*errnum = Z_STREAM_ERROR;
return ERR_MSG(Z_STREAM_ERROR);
return z_errmsg[1-Z_STREAM_ERROR];
}
*errnum = s->z_err;
if (*errnum == Z_OK) return (char*)"";
if (*errnum == Z_OK) return "";
m = (char*)(*errnum == Z_ERRNO ? zstrerror(errno) : s->stream.msg);
m = *errnum == Z_ERRNO ? zstrerror(errno) : s->stream.msg;
if (m == NULL || *m == '\0') m = (char*)z_errmsg[1-s->z_err];
if (m == NULL || *m == '\0') m = z_errmsg[1-s->z_err];
TRYFREE(s->msg);
s->msg = (char*)ALLOC(strlen(s->path) + strlen(m) + 3);