archive_read_support_compression_gzip.c [plain text]
#include "archive_platform.h"
__FBSDID("$FreeBSD: head/lib/libarchive/archive_read_support_compression_gzip.c 201082 2009-12-28 02:05:28Z kientzle $");
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_ZLIB_H
#include <zlib.h>
#endif
#include "archive.h"
#include "archive_private.h"
#include "archive_read_private.h"
#ifdef HAVE_ZLIB_H
struct private_data {
z_stream stream;
char in_stream;
unsigned char *out_block;
size_t out_block_size;
int64_t total_out;
unsigned long crc;
char eof;
};
static ssize_t gzip_filter_read(struct archive_read_filter *, const void **);
static int gzip_filter_close(struct archive_read_filter *);
#endif
static int gzip_bidder_bid(struct archive_read_filter_bidder *,
struct archive_read_filter *);
static int gzip_bidder_init(struct archive_read_filter *);
int
archive_read_support_compression_gzip(struct archive *_a)
{
struct archive_read *a = (struct archive_read *)_a;
struct archive_read_filter_bidder *bidder = __archive_read_get_bidder(a);
if (bidder == NULL)
return (ARCHIVE_FATAL);
bidder->data = NULL;
bidder->bid = gzip_bidder_bid;
bidder->init = gzip_bidder_init;
bidder->options = NULL;
bidder->free = NULL;
#if HAVE_ZLIB_H
return (ARCHIVE_OK);
#else
archive_set_error(_a, ARCHIVE_ERRNO_MISC,
"Using external gunzip program");
return (ARCHIVE_WARN);
#endif
}
static int
peek_at_header(struct archive_read_filter *filter, int *pbits)
{
const unsigned char *p;
ssize_t avail, len;
int bits = 0;
int header_flags;
len = 10;
p = __archive_read_filter_ahead(filter, len, &avail);
if (p == NULL || avail == 0)
return (0);
if (p[0] != 037)
return (0);
bits += 8;
if (p[1] != 0213)
return (0);
bits += 8;
if (p[2] != 8)
return (0);
bits += 8;
if ((p[3] & 0xE0)!= 0)
return (0);
bits += 3;
header_flags = p[3];
if (header_flags & 4) {
p = __archive_read_filter_ahead(filter, len + 2, &avail);
if (p == NULL)
return (0);
len += ((int)p[len + 1] << 8) | (int)p[len];
len += 2;
}
if (header_flags & 8) {
do {
++len;
if (avail < len)
p = __archive_read_filter_ahead(filter,
len, &avail);
if (p == NULL)
return (0);
} while (p[len - 1] != 0);
}
if (header_flags & 16) {
do {
++len;
if (avail < len)
p = __archive_read_filter_ahead(filter,
len, &avail);
if (p == NULL)
return (0);
} while (p[len - 1] != 0);
}
if ((header_flags & 2)) {
p = __archive_read_filter_ahead(filter, len + 2, &avail);
if (p == NULL)
return (0);
#if 0
int hcrc = ((int)p[len + 1] << 8) | (int)p[len];
int crc = ;
if (crc != hcrc)
return (0);
bits += 16;
#endif
len += 2;
}
if (pbits != NULL)
*pbits = bits;
return (len);
}
static int
gzip_bidder_bid(struct archive_read_filter_bidder *self,
struct archive_read_filter *filter)
{
int bits_checked;
(void)self;
if (peek_at_header(filter, &bits_checked))
return (bits_checked);
return (0);
}
#ifndef HAVE_ZLIB_H
static int
gzip_bidder_init(struct archive_read_filter *self)
{
int r;
r = __archive_read_program(self, "gunzip");
self->code = ARCHIVE_COMPRESSION_GZIP;
self->name = "gzip";
return (r);
}
#else
static int
gzip_bidder_init(struct archive_read_filter *self)
{
struct private_data *state;
static const size_t out_block_size = 64 * 1024;
void *out_block;
self->code = ARCHIVE_COMPRESSION_GZIP;
self->name = "gzip";
state = (struct private_data *)calloc(sizeof(*state), 1);
out_block = (unsigned char *)malloc(out_block_size);
if (state == NULL || out_block == NULL) {
free(out_block);
free(state);
archive_set_error(&self->archive->archive, ENOMEM,
"Can't allocate data for gzip decompression");
return (ARCHIVE_FATAL);
}
self->data = state;
state->out_block_size = out_block_size;
state->out_block = out_block;
self->read = gzip_filter_read;
self->skip = NULL;
self->close = gzip_filter_close;
state->in_stream = 0;
return (ARCHIVE_OK);
}
static int
consume_header(struct archive_read_filter *self)
{
struct private_data *state;
ssize_t avail;
size_t len;
int ret;
state = (struct private_data *)self->data;
len = peek_at_header(self->upstream, NULL);
if (len == 0)
return (ARCHIVE_EOF);
__archive_read_filter_consume(self->upstream, len);
state->crc = crc32(0L, NULL, 0);
state->stream.next_in = (unsigned char *)(uintptr_t)
__archive_read_filter_ahead(self->upstream, 1, &avail);
state->stream.avail_in = avail;
ret = inflateInit2(&(state->stream),
-15 );
switch (ret) {
case Z_OK:
state->in_stream = 1;
return (ARCHIVE_OK);
case Z_STREAM_ERROR:
archive_set_error(&self->archive->archive,
ARCHIVE_ERRNO_MISC,
"Internal error initializing compression library: "
"invalid setup parameter");
break;
case Z_MEM_ERROR:
archive_set_error(&self->archive->archive, ENOMEM,
"Internal error initializing compression library: "
"out of memory");
break;
case Z_VERSION_ERROR:
archive_set_error(&self->archive->archive,
ARCHIVE_ERRNO_MISC,
"Internal error initializing compression library: "
"invalid library version");
break;
default:
archive_set_error(&self->archive->archive,
ARCHIVE_ERRNO_MISC,
"Internal error initializing compression library: "
" Zlib error %d", ret);
break;
}
return (ARCHIVE_FATAL);
}
static int
consume_trailer(struct archive_read_filter *self)
{
struct private_data *state;
const unsigned char *p;
ssize_t avail;
state = (struct private_data *)self->data;
state->in_stream = 0;
switch (inflateEnd(&(state->stream))) {
case Z_OK:
break;
default:
archive_set_error(&self->archive->archive,
ARCHIVE_ERRNO_MISC,
"Failed to clean up gzip decompressor");
return (ARCHIVE_FATAL);
}
p = __archive_read_filter_ahead(self->upstream, 8, &avail);
if (p == NULL || avail == 0)
return (ARCHIVE_FATAL);
__archive_read_filter_consume(self->upstream, 8);
return (ARCHIVE_OK);
}
static ssize_t
gzip_filter_read(struct archive_read_filter *self, const void **p)
{
struct private_data *state;
size_t decompressed;
ssize_t avail_in;
int ret;
state = (struct private_data *)self->data;
state->stream.next_out = state->out_block;
state->stream.avail_out = state->out_block_size;
while (state->stream.avail_out > 0 && !state->eof) {
if (!state->in_stream) {
ret = consume_header(self);
if (ret == ARCHIVE_EOF) {
state->eof = 1;
break;
}
if (ret < ARCHIVE_OK)
return (ret);
}
state->stream.next_in = (unsigned char *)(uintptr_t)
__archive_read_filter_ahead(self->upstream, 1, &avail_in);
if (state->stream.next_in == NULL)
return (ARCHIVE_FATAL);
state->stream.avail_in = avail_in;
ret = inflate(&(state->stream), 0);
switch (ret) {
case Z_OK:
__archive_read_filter_consume(self->upstream,
avail_in - state->stream.avail_in);
break;
case Z_STREAM_END:
__archive_read_filter_consume(self->upstream,
avail_in - state->stream.avail_in);
ret = consume_trailer(self);
if (ret < ARCHIVE_OK)
return (ret);
break;
default:
archive_set_error(&self->archive->archive,
ARCHIVE_ERRNO_MISC,
"gzip decompression failed");
return (ARCHIVE_FATAL);
}
}
decompressed = state->stream.next_out - state->out_block;
state->total_out += decompressed;
if (decompressed == 0)
*p = NULL;
else
*p = state->out_block;
return (decompressed);
}
static int
gzip_filter_close(struct archive_read_filter *self)
{
struct private_data *state;
int ret;
state = (struct private_data *)self->data;
ret = ARCHIVE_OK;
if (state->in_stream) {
switch (inflateEnd(&(state->stream))) {
case Z_OK:
break;
default:
archive_set_error(&(self->archive->archive),
ARCHIVE_ERRNO_MISC,
"Failed to clean up gzip compressor");
ret = ARCHIVE_FATAL;
}
}
free(state->out_block);
free(state);
return (ret);
}
#endif