1 /* vi: set sw=4 ts=4: */
3 * Gzip implementation for busybox
5 * Based on GNU gzip v1.2.4 Copyright (C) 1992-1993 Jean-loup Gailly.
7 * Originally adjusted for busybox by Sven Rudolph <sr1@inf.tu-dresden.de>
8 * based on gzip sources
10 * Adjusted further by Erik Andersen <andersen@codepoet.org> to support files as
11 * well as stdin/stdout, and to generally behave itself wrt command line
14 * General cleanup to better adhere to the style guide and make use of standard
15 * busybox functions by Glenn McGrath <bug1@iinet.net.au>
17 * This program is free software; you can redistribute it and/or modify
18 * it under the terms of the GNU General Public License as published by
19 * the Free Software Foundation; either version 2 of the License, or
20 * (at your option) any later version.
22 * This program is distributed in the hope that it will be useful,
23 * but WITHOUT ANY WARRANTY; without even the implied warranty of
24 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
25 * General Public License for more details.
27 * You should have received a copy of the GNU General Public License
28 * along with this program; if not, write to the Free Software
29 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
32 * gzip (GNU zip) -- compress files with zip algorithm and 'compress' interface
33 * Copyright (C) 1992-1993 Jean-loup Gailly
34 * The unzip code was written and put in the public domain by Mark Adler.
35 * Portions of the lzw code are derived from the public domain 'compress'
36 * written by Spencer Thomas, Joe Orost, James Woods, Jim McKie, Steve Davies,
37 * Ken Turkowski, Dave Mack and Peter Jannesen.
39 * See the license_msg below and the file COPYING for the software license.
40 * See the file algorithm.doc for the compression algorithms and file formats.
46 #include <sys/types.h>
51 #include "unarchive.h"
53 #define GUNZIP_OPT_STDOUT 1
54 #define GUNZIP_OPT_FORCE 2
55 #define GUNZIP_OPT_TEST 4
56 #define GUNZIP_OPT_DECOMPRESS 8
58 int gunzip_main(int argc, char **argv)
60 char status = EXIT_SUCCESS;
63 opt = bb_getopt_ulflags(argc, argv, "cftd");
64 /* if called as zcat */
65 if (strcmp(bb_applet_name, "zcat") == 0) {
66 opt |= GUNZIP_OPT_STDOUT;
71 const char *old_path = argv[optind];
72 const char *delete_path = NULL;
73 char *new_path = NULL;
79 if (old_path == NULL || strcmp(old_path, "-") == 0) {
80 src_fd = STDIN_FILENO;
81 opt |= GUNZIP_OPT_STDOUT;
83 src_fd = bb_xopen(old_path, O_RDONLY);
85 /* Get the time stamp on the input file. */
86 xstat(old_path, &stat_buf);
89 /* Check that the input is sane. */
90 if (isatty(src_fd) && ((opt & GUNZIP_OPT_FORCE) == 0)) {
92 ("compressed data not read from terminal. Use -f to force it.");
95 /* Set output filename and number */
96 if (opt & GUNZIP_OPT_TEST) {
97 dst_fd = bb_xopen(bb_dev_null, O_WRONLY); /* why does test use filenum 2 ? */
98 } else if (opt & GUNZIP_OPT_STDOUT) {
99 dst_fd = STDOUT_FILENO;
103 new_path = bb_xstrdup(old_path);
105 extension = strrchr(new_path, '.');
106 #ifdef CONFIG_FEATURE_GUNZIP_UNCOMPRESS
107 if (extension && (strcmp(extension, ".Z") == 0)) {
111 if (extension && (strcmp(extension, ".gz") == 0)) {
113 } else if (extension && (strcmp(extension, ".tgz") == 0)) {
117 bb_error_msg_and_die("Invalid extension");
120 /* Open output file (with correct permissions) */
121 dst_fd = bb_xopen3(new_path, O_WRONLY | O_CREAT, stat_buf.st_mode);
123 /* If unzip succeeds remove the old file */
124 delete_path = old_path;
127 /* do the decompression, and cleanup */
128 if (bb_xread_char(src_fd) == 0x1f) {
129 unsigned char magic2;
131 magic2 = bb_xread_char(src_fd);
132 #ifdef CONFIG_FEATURE_GUNZIP_UNCOMPRESS
133 if (magic2 == 0x9d) {
134 status = uncompress(src_fd, dst_fd);
137 if (magic2 == 0x8b) {
138 check_header_gzip(src_fd);
139 status = inflate_gunzip(src_fd, dst_fd);
141 bb_error_msg_and_die("Error inflating");
144 bb_error_msg_and_die("Invalid magic");
147 bb_error_msg_and_die("Invalid magic");
150 if ((status != EXIT_SUCCESS) && (new_path)) {
151 /* Unzip failed, remove new path instead of old path */
152 delete_path = new_path;
155 if (dst_fd != STDOUT_FILENO) {
158 if (src_fd != STDIN_FILENO) {
162 /* delete_path will be NULL if in test mode or from stdin */
163 if (delete_path && (unlink(delete_path) == -1)) {
164 bb_error_msg_and_die("Couldn't remove %s", delete_path);
169 } while (optind < argc);