diff options
Diffstat (limited to 'archival/gunzip.c')
| -rw-r--r-- | archival/gunzip.c | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/archival/gunzip.c b/archival/gunzip.c new file mode 100644 index 000000000..e24401c71 --- /dev/null +++ b/archival/gunzip.c @@ -0,0 +1,162 @@ +/* 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 + * 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 + * 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. + */ + +#include "busybox.h" +#include "unarchive.h" + +#define GUNZIP_OPT_STDOUT 1 +#define GUNZIP_OPT_FORCE 2 +#define GUNZIP_OPT_TEST 4 +#define GUNZIP_OPT_DECOMPRESS 8 +#define GUNZIP_OPT_VERBOSE 0x10 + +int gunzip_main(int argc, char **argv) +{ + USE_DESKTOP(long long) int status; + int exitcode = 0; + unsigned opt; + + opt = getopt32(argc, argv, "cftdv"); + /* if called as zcat */ + if (strcmp(applet_name, "zcat") == 0) { + opt |= GUNZIP_OPT_STDOUT; + } + + do { + struct stat stat_buf; + char *old_path = argv[optind]; + char *delete_path = NULL; + char *new_path = NULL; + int src_fd; + int dst_fd; + + optind++; + + if (old_path == NULL || strcmp(old_path, "-") == 0) { + src_fd = STDIN_FILENO; + opt |= GUNZIP_OPT_STDOUT; + USE_DESKTOP(opt &= ~GUNZIP_OPT_VERBOSE;) + optind = argc; /* we don't handle "gunzip - a.gz b.gz" */ + } else { + src_fd = xopen(old_path, O_RDONLY); + /* Get the time stamp on the input file. */ + fstat(src_fd, &stat_buf); + } + + /* Check that the input is sane. */ + if (isatty(src_fd) && !(opt & GUNZIP_OPT_FORCE)) { + bb_error_msg_and_die + ("compressed data not read from terminal, use -f to force it"); + } + + /* Set output filename and number */ + if (opt & GUNZIP_OPT_TEST) { + dst_fd = xopen(bb_dev_null, O_WRONLY); /* why does test use filenum 2 ? */ + } else if (opt & GUNZIP_OPT_STDOUT) { + dst_fd = STDOUT_FILENO; + } else { + char *extension; + + new_path = 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 { + // FIXME: should we die or just skip to next? + bb_error_msg_and_die("invalid extension"); + } + + /* Open output file (with correct permissions) */ + dst_fd = xopen3(new_path, O_WRONLY | O_CREAT | O_TRUNC, + stat_buf.st_mode); + + /* If unzip succeeds remove the old file */ + delete_path = old_path; + } + + status = -1; + /* do the decompression, and cleanup */ + if (xread_char(src_fd) == 0x1f) { + unsigned char magic2; + + magic2 = xread_char(src_fd); + if (ENABLE_FEATURE_GUNZIP_UNCOMPRESS && magic2 == 0x9d) { + status = uncompress(src_fd, dst_fd); + } else if (magic2 == 0x8b) { + check_header_gzip(src_fd); // FIXME: xfunc? _or_die? + status = inflate_gunzip(src_fd, dst_fd); + } else { + bb_error_msg("invalid magic"); + exitcode = 1; + } + if (status < 0) { + bb_error_msg("error inflating"); + exitcode = 1; + } + else if (ENABLE_DESKTOP && (opt & GUNZIP_OPT_VERBOSE)) { + fprintf(stderr, "%s: %u%% - replaced with %s\n", + old_path, (unsigned)(stat_buf.st_size*100 / (status+1)), new_path); + } + } else { + bb_error_msg("invalid magic"); + exitcode = 1; + } + if (status < 0 && new_path) { + /* Unzip failed, remove new path instead of old path */ + delete_path = new_path; + } + + if (dst_fd != STDOUT_FILENO) { + close(dst_fd); + } + if (src_fd != STDIN_FILENO) { + close(src_fd); + } + + /* delete_path will be NULL if in test mode or from stdin */ + if (delete_path && (unlink(delete_path) == -1)) { + bb_error_msg("cannot remove %s", delete_path); + exitcode = 1; + } + + free(new_path); + + } while (optind < argc); + + return exitcode; +} |