busybox/libbb/extract_archive.c

133 lines
4.4 KiB
C

/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Library General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <utime.h>
#include "libbb.h"
/* Extract files in the linear linked list 'extract_headers' to either
* filesystem, stdout or buffer depending on the value of 'function' which is
* described in extract_files.h
*
* prefix doesnt have to be just a directory, it may prefix the filename as well.
*
* e.g. '/var/lib/dpkg/info/dpkg.' will extract all files to the base bath
* '/var/lib/dpkg/info/' and all files/dirs created in that dir will have
* 'dpkg.' as their prefix
*
* For this reason if prefix does point to a dir then it must end with a
* trailing '/' or else the last dir will be assumed to be the file prefix
*/
char *extract_archive(FILE *src_stream, FILE *out_stream, file_headers_t *extract_headers, int function, const char *prefix)
{
FILE *dst_stream = NULL;
char *full_name = NULL;
char *buffer = NULL;
size_t uncompressed_count = 0;
struct utimbuf t;
/* find files to extract or display */
while (extract_headers != NULL) {
/* prefix doesnt have to be a proper path it may prepend
* the filename as well */
if (prefix != NULL) {
/* strip leading '/' in filename to extract as prefix may not be dir */
char *tmp_str = strchr(extract_headers->name, '/');
if (tmp_str == NULL) {
tmp_str = extract_headers->name;
} else {
tmp_str++;
}
/* Cant use concat_path_file here as prefix might not be a directory */
full_name = xmalloc(strlen(prefix) + strlen(tmp_str) + 1);
strcpy(full_name, prefix);
strcat(full_name, tmp_str);
} else {
full_name = extract_headers->name;
}
/* Seek to start of file, have to use fgetc as src_stream may be a pipe
* you cant [lf]seek on pipes */
while (uncompressed_count < extract_headers->offset) {
fgetc(src_stream);
uncompressed_count++;
}
if (S_ISREG(extract_headers->mode)) {
if (function & extract_to_stdout) {
copy_file_chunk(src_stream, out_stream, extract_headers->size);
uncompressed_count += extract_headers->size;
}
else if (function & extract_all_to_fs) {
dst_stream = wfopen(full_name, "w");
copy_file_chunk(src_stream, dst_stream, extract_headers->size);
uncompressed_count += extract_headers->size;
fclose(dst_stream);
}
else if (function & extract_one_to_buffer) {
buffer = (char *) xmalloc(extract_headers->size + 1);
fread(buffer, 1, extract_headers->size, src_stream);
break;
}
}
#if defined BB_DPKG | defined BB_DPKG_DEB
else if (S_ISDIR(extract_headers->mode)) {
if (function & extract_all_to_fs) {
if (create_path(full_name, extract_headers->mode) == FALSE) {
perror_msg("Cannot mkdir %s", extract_headers->name);
return NULL;
}
}
}
else if (S_ISLNK(extract_headers->mode)) {
if (function & extract_all_to_fs) {
if (symlink(extract_headers->link_name, full_name) < 0) {
perror_msg("Cannot create hard link from %s to '%s'", extract_headers->name, extract_headers->link_name);
return NULL;
}
}
}
#endif
if (function & extract_verbose_list) {
fprintf(out_stream, "%s %d/%d %8d %s ", mode_string(extract_headers->mode),
extract_headers->uid, extract_headers->gid,
(int) extract_headers->size, time_string(extract_headers->mtime));
}
if ((function & extract_list) || (function & extract_verbose_list)){
/* fputs doesnt add a trailing \n, so use fprintf */
fprintf(out_stream, "%s\n", extract_headers->name);
}
if (function & extract_preserve_date) {
t.actime = extract_headers->mtime;
t.modtime = extract_headers->mtime;
utime(full_name, &t);
}
chmod(full_name, extract_headers->mode);
free(full_name);
extract_headers = extract_headers->next;
}
return(buffer);
}