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 <andersee@debian.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@optushome.com.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.
44 static char *license_msg[] = {
45 " Copyright (C) 1992-1993 Jean-loup Gailly",
46 " This program is free software; you can redistribute it and/or modify",
47 " it under the terms of the GNU General Public License as published by",
48 " the Free Software Foundation; either version 2, or (at your option)",
49 " any later version.",
51 " This program is distributed in the hope that it will be useful,",
52 " but WITHOUT ANY WARRANTY; without even the implied warranty of",
53 " MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the",
54 " GNU General Public License for more details.",
56 " You should have received a copy of the GNU General Public License",
57 " along with this program; if not, write to the Free Software",
58 " Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.",
67 #include <sys/types.h>
72 #include "unarchive.h"
74 const char gunzip_to_stdout = 1;
75 const char gunzip_force = 2;
76 const char gunzip_test = 4;
78 extern int gunzip_main(int argc, char **argv)
80 char status = EXIT_SUCCESS;
84 /* if called as zcat */
85 if (strcmp(applet_name, "zcat") == 0) {
86 flags |= gunzip_to_stdout;
89 while ((opt = getopt(argc, argv, "ctfhd")) != -1) {
92 flags |= gunzip_to_stdout;
95 flags |= gunzip_force;
100 case 'd': /* Used to convert gzip to gunzip. */
103 show_usage(); /* exit's inside usage */
108 struct stat stat_buf;
109 const char *old_path = argv[optind];
110 const char *delete_path = NULL;
111 char *new_path = NULL;
117 if (old_path == NULL || strcmp(old_path, "-") == 0) {
118 src_fd = fileno(stdin);
119 flags |= gunzip_to_stdout;
121 src_fd = xopen(old_path, O_RDONLY);
123 /* Get the time stamp on the input file. */
124 if (stat(old_path, &stat_buf) < 0) {
125 error_msg_and_die("Couldn't stat file %s", old_path);
129 /* Check that the input is sane. */
130 if (isatty(src_fd) && ((flags & gunzip_force) == 0)) {
132 ("compressed data not read from terminal. Use -f to force it.");
135 /* Set output filename and number */
136 if (flags & gunzip_test) {
137 dst_fd = xopen("/dev/null", O_WRONLY); /* why does test use filenum 2 ? */
138 } else if (flags & gunzip_to_stdout) {
139 dst_fd = fileno(stdout);
143 new_path = xstrdup(old_path);
145 extension = strrchr(new_path, '.');
146 #ifdef CONFIG_FEATURE_GUNZIP_UNCOMPRESS
147 if (extension && (strcmp(extension, ".Z") == 0)) {
151 if (extension && (strcmp(extension, ".gz") == 0)) {
153 } else if (extension && (strcmp(extension, ".tgz") == 0)) {
157 error_msg_and_die("Invalid extension");
160 /* Open output file */
161 dst_fd = xopen(new_path, O_WRONLY | O_CREAT);
163 /* Set permissions on the file */
164 chmod(new_path, stat_buf.st_mode);
166 /* If unzip succeeds remove the old file */
167 delete_path = old_path;
170 /* do the decompression, and cleanup */
171 if (xread_char(src_fd) == 0x1f) {
172 unsigned char magic2;
174 magic2 = xread_char(src_fd);
175 #ifdef CONFIG_FEATURE_GUNZIP_UNCOMPRESS
176 if (magic2 == 0x9d) {
177 status = uncompress(src_fd, dst_fd);
180 if (magic2 == 0x8b) {
181 check_header_gzip(src_fd);
182 status = inflate(src_fd, dst_fd);
184 error_msg_and_die("Error inflating");
186 check_trailer_gzip(src_fd);
188 error_msg_and_die("Invalid magic");
191 error_msg_and_die("Invalid magic");
194 if ((status != EXIT_SUCCESS) && (new_path)) {
195 /* Unzip failed, remove new path instead of old path */
196 delete_path = new_path;
199 if (dst_fd != fileno(stdout)) {
202 if (src_fd != fileno(stdin)) {
206 /* delete_path will be NULL if in test mode or from stdin */
207 if (delete_path && (unlink(delete_path) == -1)) {
208 error_msg_and_die("Couldn't remove %s", delete_path);
213 } while (optind < argc);