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 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
19 * gzip (GNU zip) -- compress files with zip algorithm and 'compress' interface
20 * Copyright (C) 1992-1993 Jean-loup Gailly
21 * The unzip code was written and put in the public domain by Mark Adler.
22 * Portions of the lzw code are derived from the public domain 'compress'
23 * written by Spencer Thomas, Joe Orost, James Woods, Jim McKie, Steve Davies,
24 * Ken Turkowski, Dave Mack and Peter Jannesen.
26 * See the license_msg below and the file COPYING for the software license.
27 * See the file algorithm.doc for the compression algorithms and file formats.
31 #include "unarchive.h"
33 #define GUNZIP_OPT_STDOUT 1
34 #define GUNZIP_OPT_FORCE 2
35 #define GUNZIP_OPT_TEST 4
36 #define GUNZIP_OPT_DECOMPRESS 8
37 #define GUNZIP_OPT_VERBOSE 0x10
39 int gunzip_main(int argc, char **argv)
41 USE_DESKTOP(long long) int status;
45 opt = getopt32(argc, argv, "cftdv");
46 /* if called as zcat */
47 if (strcmp(applet_name, "zcat") == 0) {
48 opt |= GUNZIP_OPT_STDOUT;
53 char *old_path = argv[optind];
54 char *delete_path = NULL;
55 char *new_path = NULL;
61 if (old_path == NULL || strcmp(old_path, "-") == 0) {
62 src_fd = STDIN_FILENO;
63 opt |= GUNZIP_OPT_STDOUT;
64 USE_DESKTOP(opt &= ~GUNZIP_OPT_VERBOSE;)
65 optind = argc; /* we don't handle "gunzip - a.gz b.gz" */
67 src_fd = xopen(old_path, O_RDONLY);
68 /* Get the time stamp on the input file. */
69 fstat(src_fd, &stat_buf);
72 /* Check that the input is sane. */
73 if (isatty(src_fd) && !(opt & GUNZIP_OPT_FORCE)) {
75 ("compressed data not read from terminal, use -f to force it");
78 /* Set output filename and number */
79 if (opt & GUNZIP_OPT_TEST) {
80 dst_fd = xopen(bb_dev_null, O_WRONLY); /* why does test use filenum 2 ? */
81 } else if (opt & GUNZIP_OPT_STDOUT) {
82 dst_fd = STDOUT_FILENO;
86 new_path = xstrdup(old_path);
88 extension = strrchr(new_path, '.');
89 #ifdef CONFIG_FEATURE_GUNZIP_UNCOMPRESS
90 if (extension && (strcmp(extension, ".Z") == 0)) {
94 if (extension && (strcmp(extension, ".gz") == 0)) {
96 } else if (extension && (strcmp(extension, ".tgz") == 0)) {
100 // FIXME: should we die or just skip to next?
101 bb_error_msg_and_die("invalid extension");
104 /* Open output file (with correct permissions) */
105 dst_fd = xopen3(new_path, O_WRONLY | O_CREAT | O_TRUNC,
108 /* If unzip succeeds remove the old file */
109 delete_path = old_path;
113 /* do the decompression, and cleanup */
114 if (xread_char(src_fd) == 0x1f) {
115 unsigned char magic2;
117 magic2 = xread_char(src_fd);
118 if (ENABLE_FEATURE_GUNZIP_UNCOMPRESS && magic2 == 0x9d) {
119 status = uncompress(src_fd, dst_fd);
120 } else if (magic2 == 0x8b) {
121 check_header_gzip(src_fd); // FIXME: xfunc? _or_die?
122 status = inflate_gunzip(src_fd, dst_fd);
124 bb_error_msg("invalid magic");
128 bb_error_msg("error inflating");
131 else if (ENABLE_DESKTOP && (opt & GUNZIP_OPT_VERBOSE)) {
132 fprintf(stderr, "%s: %u%% - replaced with %s\n",
133 old_path, (unsigned)(stat_buf.st_size*100 / (status+1)), new_path);
136 bb_error_msg("invalid magic");
139 if (status < 0 && new_path) {
140 /* Unzip failed, remove new path instead of old path */
141 delete_path = new_path;
144 if (dst_fd != STDOUT_FILENO) {
147 if (src_fd != STDIN_FILENO) {
151 /* delete_path will be NULL if in test mode or from stdin */
152 if (delete_path && (unlink(delete_path) == -1)) {
153 bb_error_msg("cannot remove %s", delete_path);
159 } while (optind < argc);