busybox/archival/gunzip.c

160 lines
4.2 KiB
C
Raw Normal View History

/* vi: set sw=4 ts=4: */
/*
* Gzip implementation for busybox
*
* Based on GNU gzip v1.2.4 Copyright (C) 1992-1993 Jean-loup Gailly.
*
* Originally adjusted for busybox by Sven Rudolph <sr1@inf.tu-dresden.de>
* based on gzip sources
*
* Adjusted further by Erik Andersen <andersen@codepoet.org> to support files as
2002-04-06 10:45:46 +05:30
* well as stdin/stdout, and to generally behave itself wrt command line
* handling.
*
* General cleanup to better adhere to the style guide and make use of standard
* busybox functions by Glenn McGrath <bug1@iinet.net.au>
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*
* gzip (GNU zip) -- compress files with zip algorithm and 'compress' interface
1999-11-18 05:51:59 +05:30
* Copyright (C) 1992-1993 Jean-loup Gailly
* The unzip code was written and put in the public domain by Mark Adler.
* Portions of the lzw code are derived from the public domain 'compress'
* written by Spencer Thomas, Joe Orost, James Woods, Jim McKie, Steve Davies,
* Ken Turkowski, Dave Mack and Peter Jannesen.
*
* See the license_msg below and the file COPYING for the software license.
* See the file algorithm.doc for the compression algorithms and file formats.
*/
2001-04-11 08:41:33 +05:30
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
2002-09-25 08:17:48 +05:30
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include "busybox.h"
2002-09-25 08:17:48 +05:30
#include "unarchive.h"
1999-11-18 05:51:59 +05:30
2004-01-05 18:05:05 +05:30
#define GUNZIP_OPT_STDOUT 1
#define GUNZIP_OPT_FORCE 2
#define GUNZIP_OPT_TEST 4
#define GUNZIP_OPT_DECOMPRESS 8
int gunzip_main(int argc, char **argv)
{
char status = EXIT_SUCCESS;
2004-01-05 18:05:05 +05:30
unsigned long opt;
2004-01-05 18:05:05 +05:30
opt = bb_getopt_ulflags(argc, argv, "cftd");
/* if called as zcat */
2003-03-19 14:43:01 +05:30
if (strcmp(bb_applet_name, "zcat") == 0) {
2004-01-05 18:05:05 +05:30
opt |= GUNZIP_OPT_STDOUT;
}
do {
struct stat stat_buf;
const char *old_path = argv[optind];
const char *delete_path = NULL;
char *new_path = NULL;
2002-09-25 08:17:48 +05:30
int src_fd;
int dst_fd;
optind++;
if (old_path == NULL || strcmp(old_path, "-") == 0) {
src_fd = STDIN_FILENO;
2004-01-05 18:05:05 +05:30
opt |= GUNZIP_OPT_STDOUT;
} else {
2003-03-19 14:43:01 +05:30
src_fd = bb_xopen(old_path, O_RDONLY);
/* Get the time stamp on the input file. */
xstat(old_path, &stat_buf);
2002-08-24 16:00:36 +05:30
}
/* Check that the input is sane. */
2004-01-05 18:05:05 +05:30
if (isatty(src_fd) && ((opt & GUNZIP_OPT_FORCE) == 0)) {
2003-03-19 14:43:01 +05:30
bb_error_msg_and_die
("compressed data not read from terminal. Use -f to force it.");
}
/* Set output filename and number */
2004-01-05 18:05:05 +05:30
if (opt & GUNZIP_OPT_TEST) {
2005-10-12 21:04:25 +05:30
dst_fd = bb_xopen(bb_dev_null, O_WRONLY); /* why does test use filenum 2 ? */
2004-01-05 18:05:05 +05:30
} else if (opt & GUNZIP_OPT_STDOUT) {
dst_fd = STDOUT_FILENO;
} else {
char *extension;
2003-03-19 14:43:01 +05:30
new_path = bb_xstrdup(old_path);
extension = strrchr(new_path, '.');
#ifdef CONFIG_FEATURE_GUNZIP_UNCOMPRESS
if (extension && (strcmp(extension, ".Z") == 0)) {
*extension = '\0';
} else
#endif
if (extension && (strcmp(extension, ".gz") == 0)) {
*extension = '\0';
} else if (extension && (strcmp(extension, ".tgz") == 0)) {
extension[2] = 'a';
extension[3] = 'r';
} else {
2003-03-19 14:43:01 +05:30
bb_error_msg_and_die("Invalid extension");
}
/* Open output file (with correct permissions) */
dst_fd = bb_xopen3(new_path, O_WRONLY | O_CREAT, stat_buf.st_mode);
/* If unzip succeeds remove the old file */
delete_path = old_path;
}
/* do the decompression, and cleanup */
if (xread_char(src_fd) == 0x1f) {
unsigned char magic2;
magic2 = xread_char(src_fd);
#ifdef CONFIG_FEATURE_GUNZIP_UNCOMPRESS
if (magic2 == 0x9d) {
status = uncompress(src_fd, dst_fd);
} else
#endif
if (magic2 == 0x8b) {
check_header_gzip(src_fd);
status = inflate_gunzip(src_fd, dst_fd);
if (status != 0) {
2003-03-19 14:43:01 +05:30
bb_error_msg_and_die("Error inflating");
}
} else {
2003-03-19 14:43:01 +05:30
bb_error_msg_and_die("Invalid magic");
}
} else {
2003-03-19 14:43:01 +05:30
bb_error_msg_and_die("Invalid magic");
2002-09-25 08:17:48 +05:30
}
if ((status != EXIT_SUCCESS) && (new_path)) {
/* Unzip failed, remove new path instead of old path */
delete_path = new_path;
}
if (dst_fd != STDOUT_FILENO) {
2002-09-25 08:17:48 +05:30
close(dst_fd);
}
if (src_fd != STDIN_FILENO) {
2002-09-25 08:17:48 +05:30
close(src_fd);
}
/* delete_path will be NULL if in test mode or from stdin */
if (delete_path && (unlink(delete_path) == -1)) {
2003-03-19 14:43:01 +05:30
bb_error_msg_and_die("Couldn't remove %s", delete_path);
}
free(new_path);
} while (optind < argc);
return status;
1999-11-18 05:51:59 +05:30
}