archive_read_support_compression_gzip.c [plain text]
#include "archive_platform.h"
__FBSDID("$FreeBSD: src/lib/libarchive/archive_read_support_compression_gzip.c,v 1.17 2008/12/06 06:45:15 kientzle Exp $");
#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;
unsigned char *out_block;
size_t out_block_size;
int64_t total_out;
unsigned long crc;
int header_count;
char header_done;
char header_state;
char header_flags;
char eof;
};
static ssize_t gzip_source_read(struct archive_read_source *, const void **);
static int gzip_source_close(struct archive_read_source *);
#endif
static int gzip_reader_bid(struct archive_reader *, const void *, size_t);
static struct archive_read_source *gzip_reader_init(struct archive_read *,
struct archive_reader *, struct archive_read_source *,
const void *, size_t);
static int gzip_reader_free(struct archive_reader *);
int
archive_read_support_compression_gzip(struct archive *_a)
{
struct archive_read *a = (struct archive_read *)_a;
struct archive_reader *reader = __archive_read_get_reader(a);
if (reader == NULL)
return (ARCHIVE_FATAL);
reader->data = NULL;
reader->bid = gzip_reader_bid;
reader->init = gzip_reader_init;
reader->free = gzip_reader_free;
return (ARCHIVE_OK);
}
static int
gzip_reader_free(struct archive_reader *self){
(void)self;
return (ARCHIVE_OK);
}
static int
gzip_reader_bid(struct archive_reader *self, const void *buff, size_t len)
{
const unsigned char *buffer;
int bits_checked;
(void)self;
if (len < 1)
return (0);
buffer = (const unsigned char *)buff;
bits_checked = 0;
if (buffer[0] != 037)
return (0);
bits_checked += 8;
if (len < 2)
return (bits_checked);
if (buffer[1] != 0213)
return (0);
bits_checked += 8;
if (len < 3)
return (bits_checked);
if (buffer[2] != 8)
return (0);
bits_checked += 8;
if (len < 4)
return (bits_checked);
if ((buffer[3] & 0xE0)!= 0)
return (0);
bits_checked += 3;
if (len < 5)
return (bits_checked);
return (bits_checked);
}
#ifndef HAVE_ZLIB_H
static struct archive_read_source *
gzip_reader_init(struct archive_read *a, struct archive_reader *reader,
struct archive_read_source *upstream, const void *buff, size_t n)
{
(void)a;
(void)reader;
(void)upstream;
(void)buff;
(void)n;
archive_set_error(&a->archive, -1,
"This version of libarchive was compiled without gzip support");
return (NULL);
}
#else
static struct archive_read_source *
gzip_reader_init(struct archive_read *a, struct archive_reader *reader,
struct archive_read_source *upstream, const void *buff, size_t n)
{
static const size_t out_block_size = 64 * 1024;
void *out_block;
struct archive_read_source *self;
struct private_data *state;
(void)reader;
a->archive.compression_code = ARCHIVE_COMPRESSION_GZIP;
a->archive.compression_name = "gzip";
self = calloc(sizeof(*self), 1);
state = (struct private_data *)calloc(sizeof(*state), 1);
out_block = (unsigned char *)malloc(out_block_size);
if (self == NULL || state == NULL || out_block == NULL) {
archive_set_error(&a->archive, ENOMEM,
"Can't allocate data for %s decompression",
a->archive.compression_name);
free(out_block);
free(state);
free(self);
return (NULL);
}
self->archive = a;
self->data = state;
state->out_block_size = out_block_size;
state->out_block = out_block;
self->upstream = upstream;
self->read = gzip_source_read;
self->skip = NULL;
self->close = gzip_source_close;
state->crc = crc32(0L, NULL, 0);
state->header_done = 0;
state->stream.next_in = (Bytef *)(uintptr_t)(const void *)buff;
state->stream.avail_in = n;
return (self);
}
static int
header(struct archive_read_source *self)
{
struct private_data *state;
int ret, b;
state = (struct private_data *)self->data;
b = *(state->stream.next_in++);
state->stream.avail_in--;
switch (state->header_state) {
case 0:
if (b != 037)
return (ARCHIVE_EOF);
state->header_state = 1;
break;
case 1:
case 2:
if (b != (0xff & "\037\213\010"[(int)state->header_state])) {
archive_set_error(&self->archive->archive,
ARCHIVE_ERRNO_MISC,
"Invalid GZip header (saw %d at offset %d)",
b, state->header_state);
return (ARCHIVE_FATAL);
}
++state->header_state;
break;
case 3:
state->header_flags = b;
state->header_state = 4;
break;
case 4: case 5: case 6: case 7:
case 8:
case 9:
++state->header_state;
break;
case 10:
if ((state->header_flags & 4)) {
state->header_count = 255 & (int)b;
state->header_state = 11;
break;
}
case 11:
if ((state->header_flags & 4)) {
state->header_count
= (0xff00 & ((int)b << 8)) | state->header_count;
state->header_state = 12;
break;
}
case 12:
if ((state->header_flags & 4)) {
--state->header_count;
if (state->header_count == 0) state->header_state = 13;
else state->header_state = 12;
break;
}
case 13:
if ((state->header_flags & 8)) {
if (b == 0) state->header_state = 14;
else state->header_state = 13;
break;
}
case 14:
if ((state->header_flags & 16)) {
if (b == 0) state->header_state = 15;
else state->header_state = 14;
break;
}
case 15:
if ((state->header_flags & 2)) {
state->header_state = 16;
break;
}
case 16:
if ((state->header_flags & 2)) {
state->header_state = 17;
break;
}
case 17:
state->header_done = 1;
state->stream.avail_in++;
state->stream.next_in--;
ret = inflateInit2(&(state->stream),
-15 );
switch (ret) {
case Z_OK:
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);
}
return (ARCHIVE_OK);
}
static ssize_t
gzip_source_read(struct archive_read_source *self, const void **p)
{
struct private_data *state;
size_t read_avail, decompressed;
const void *read_buf;
int ret;
state = (struct private_data *)self->data;
read_avail = 0;
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->stream.avail_in == 0) {
ret = (self->upstream->read)(self->upstream,
&read_buf);
state->stream.next_in
= (unsigned char *)(uintptr_t)read_buf;
if (ret < 0)
return (ARCHIVE_FATAL);
state->stream.avail_in = ret;
if (ret == 0) {
state->eof = 1;
break;
}
}
if (!state->header_done) {
ret = header(self);
if (ret < ARCHIVE_OK)
return (ret);
if (ret == ARCHIVE_EOF)
state->eof = 1;
} else {
ret = inflate(&(state->stream), 0);
switch (ret) {
case Z_STREAM_END:
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);
}
state->header_state = state->header_done = 0;
state->eof = 1;
case Z_OK:
break;
default:
archive_set_error(&self->archive->archive,
ARCHIVE_ERRNO_MISC,
"%s decompression failed",
self->archive->archive.compression_name);
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_source_close(struct archive_read_source *self)
{
struct private_data *state;
int ret;
state = (struct private_data *)self->data;
ret = ARCHIVE_OK;
if (state->header_done) {
switch (inflateEnd(&(state->stream))) {
case Z_OK:
break;
default:
archive_set_error(&(self->archive->archive),
ARCHIVE_ERRNO_MISC,
"Failed to clean up %s compressor",
self->archive->archive.compression_name);
ret = ARCHIVE_FATAL;
}
}
free(state->out_block);
free(state);
free(self);
return (ret);
}
#endif