/* vi: set sw=4 ts=4: */
/*
 * Common code for gunzip-like applets
 *
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 */
#include "libbb.h"
#include "bb_archive.h"

enum {
        OPT_STDOUT     = 1 << 0,
        OPT_FORCE      = 1 << 1,
        /* only some decompressors: */
        OPT_VERBOSE    = 1 << 2,
        OPT_DECOMPRESS = 1 << 3,
        OPT_TEST       = 1 << 4,
};

static
int open_to_or_warn(int to_fd, const char *filename, int flags, int mode)
{
        int fd = open3_or_warn(filename, flags, mode);
        if (fd < 0) {
                return 1;
        }
        xmove_fd(fd, to_fd);
        return 0;
}

char* FAST_FUNC append_ext(char *filename, const char *expected_ext)
{
        return xasprintf("%s.%s", filename, expected_ext);
}

int FAST_FUNC bbunpack(char **argv,
        IF_DESKTOP(long long) int FAST_FUNC (*unpacker)(transformer_aux_data_t *aux),
        char* FAST_FUNC (*make_new_name)(char *filename, const char *expected_ext),
        const char *expected_ext
)
{
        struct stat stat_buf;
        IF_DESKTOP(long long) int status;
        char *filename, *new_name;
        smallint exitcode = 0;
        transformer_aux_data_t aux;

        do {
                /* NB: new_name is *maybe* malloc'ed! */
                new_name = NULL;
                filename = *argv; /* can be NULL - 'streaming' bunzip2 */

                if (filename && LONE_DASH(filename))
                        filename = NULL;

                /* Open src */
                if (filename) {
                        if (stat(filename, &stat_buf) != 0) {
                                bb_simple_perror_msg(filename);
 err:
                                exitcode = 1;
                                goto free_name;
                        }
                        if (open_to_or_warn(STDIN_FILENO, filename, O_RDONLY, 0))
                                goto err;
                }

                /* Special cases: test, stdout */
                if (option_mask32 & (OPT_STDOUT|OPT_TEST)) {
                        if (option_mask32 & OPT_TEST)
                                if (open_to_or_warn(STDOUT_FILENO, bb_dev_null, O_WRONLY, 0))
                                        goto err;
                        filename = NULL;
                }

                /* Open dst if we are going to unpack to file */
                if (filename) {
                        new_name = make_new_name(filename, expected_ext);
                        if (!new_name) {
                                bb_error_msg("%s: unknown suffix - ignored", filename);
                                goto err;
                        }

                        /* -f: overwrite existing output files */
                        if (option_mask32 & OPT_FORCE) {
                                unlink(new_name);
                        }

                        /* O_EXCL: "real" bunzip2 doesn't overwrite files */
                        /* GNU gunzip does not bail out, but goes to next file */
                        if (open_to_or_warn(STDOUT_FILENO, new_name, O_WRONLY | O_CREAT | O_EXCL,
                                        stat_buf.st_mode))
                                goto err;
                }

                /* Check that the input is sane */
                if (isatty(STDIN_FILENO) && (option_mask32 & OPT_FORCE) == 0) {
                        bb_error_msg_and_die("compressed data not read from terminal, "
                                        "use -f to force it");
                }

                init_transformer_aux_data(&aux);
                aux.check_signature = 1;
                status = unpacker(&aux);
                if (status < 0)
                        exitcode = 1;

                if (!(option_mask32 & OPT_STDOUT))
                        xclose(STDOUT_FILENO); /* with error check! */

                if (filename) {
                        char *del = new_name;
                        if (status >= 0) {
                                /* TODO: restore other things? */
                                if (aux.mtime != 0) {
                                        struct timeval times[2];

                                        times[1].tv_sec = times[0].tv_sec = aux.mtime;
                                        times[1].tv_usec = times[0].tv_usec = 0;
                                        /* Note: we closed it first.
                                         * On some systems calling utimes
                                         * then closing resets the mtime
                                         * back to current time. */
                                        utimes(new_name, times); /* ignoring errors */
                                }

                                /* Delete _compressed_ file */
                                del = filename;
                                /* restore extension (unless tgz -> tar case) */
                                if (new_name == filename)
                                        filename[strlen(filename)] = '.';
                        }
                        xunlink(del);

#if 0 /* Currently buggy - wrong name: "a.gz: 261% - replaced with a.gz" */
                        /* Extreme bloat for gunzip compat */
                        if (ENABLE_DESKTOP && (option_mask32 & OPT_VERBOSE) && status >= 0) {
                                fprintf(stderr, "%s: %u%% - replaced with %s\n",
                                        filename, (unsigned)(stat_buf.st_size*100 / (status+1)), new_name);
                        }
#endif

 free_name:
                        if (new_name != filename)
                                free(new_name);
                }
        } while (*argv && *++argv);

        if (option_mask32 & OPT_STDOUT)
                xclose(STDOUT_FILENO); /* with error check! */

        return exitcode;
}

#if ENABLE_UNCOMPRESS || ENABLE_BUNZIP2 || ENABLE_UNLZMA || ENABLE_UNXZ
static
char* FAST_FUNC make_new_name_generic(char *filename, const char *expected_ext)
{
        char *extension = strrchr(filename, '.');
        if (!extension || strcmp(extension + 1, expected_ext) != 0) {
                /* Mimic GNU gunzip - "real" bunzip2 tries to */
                /* unpack file anyway, to file.out */
                return NULL;
        }
        *extension = '\0';
        return filename;
}
#endif


/*
 * Uncompress applet for busybox (c) 2002 Glenn McGrath
 *
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 */

//usage:#define uncompress_trivial_usage
//usage:       "[-cf] [FILE]..."
//usage:#define uncompress_full_usage "\n\n"
//usage:       "Decompress .Z file[s]\n"
//usage:     "\n        -c      Write to stdout"
//usage:     "\n        -f      Overwrite"

#if ENABLE_UNCOMPRESS
static
IF_DESKTOP(long long) int FAST_FUNC unpack_uncompress(transformer_aux_data_t *aux)
{
        return unpack_Z_stream(aux, STDIN_FILENO, STDOUT_FILENO);
}
int uncompress_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int uncompress_main(int argc UNUSED_PARAM, char **argv)
{
        getopt32(argv, "cf");
        argv += optind;

        return bbunpack(argv, unpack_uncompress, make_new_name_generic, "Z");
}
#endif


/*
 * 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
 *
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 *
 * 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.
 */

//usage:#define gunzip_trivial_usage
//usage:       "[-cft] [FILE]..."
//usage:#define gunzip_full_usage "\n\n"
//usage:       "Decompress FILEs (or stdin)\n"
//usage:     "\n        -c      Write to stdout"
//usage:     "\n        -f      Force"
//usage:     "\n        -t      Test file integrity"
//usage:
//usage:#define gunzip_example_usage
//usage:       "$ ls -la /tmp/BusyBox*\n"
//usage:       "-rw-rw-r--    1 andersen andersen   557009 Apr 11 10:55 /tmp/BusyBox-0.43.tar.gz\n"
//usage:       "$ gunzip /tmp/BusyBox-0.43.tar.gz\n"
//usage:       "$ ls -la /tmp/BusyBox*\n"
//usage:       "-rw-rw-r--    1 andersen andersen  1761280 Apr 14 17:47 /tmp/BusyBox-0.43.tar\n"
//usage:
//usage:#define zcat_trivial_usage
//usage:       "FILE"
//usage:#define zcat_full_usage "\n\n"
//usage:       "Decompress to stdout"

#if ENABLE_GUNZIP
static
char* FAST_FUNC make_new_name_gunzip(char *filename, const char *expected_ext UNUSED_PARAM)
{
        char *extension = strrchr(filename, '.');

        if (!extension)
                return NULL;

        extension++;
        if (strcmp(extension, "tgz" + 1) == 0
#if ENABLE_FEATURE_SEAMLESS_Z
         || (extension[0] == 'Z' && extension[1] == '\0')
#endif
        ) {
                extension[-1] = '\0';
        } else if (strcmp(extension, "tgz") == 0) {
                filename = xstrdup(filename);
                extension = strrchr(filename, '.');
                extension[2] = 'a';
                extension[3] = 'r';
        } else {
                return NULL;
        }
        return filename;
}
static
IF_DESKTOP(long long) int FAST_FUNC unpack_gunzip(transformer_aux_data_t *aux)
{
        return unpack_gz_stream(aux, STDIN_FILENO, STDOUT_FILENO);
}
/*
 * Linux kernel build uses gzip -d -n. We accept and ignore it.
 * Man page says:
 * -n --no-name
 * gzip: do not save the original file name and time stamp.
 * (The original name is always saved if the name had to be truncated.)
 * gunzip: do not restore the original file name/time even if present
 * (remove only the gzip suffix from the compressed file name).
 * This option is the default when decompressing.
 * -N --name
 * gzip: always save the original file name and time stamp (this is the default)
 * gunzip: restore the original file name and time stamp if present.
 */
int gunzip_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int gunzip_main(int argc UNUSED_PARAM, char **argv)
{
        getopt32(argv, "cfvdtn");
        argv += optind;
        /* if called as zcat */
        if (applet_name[1] == 'c')
                option_mask32 |= OPT_STDOUT;

        return bbunpack(argv, unpack_gunzip, make_new_name_gunzip, /*unused:*/ NULL);
}
#endif


/*
 * Modified for busybox by Glenn McGrath
 * Added support output to stdout by Thomas Lundquist <thomasez@zelow.no>
 *
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 */
//usage:#define bunzip2_trivial_usage
//usage:       "[-cf] [FILE]..."
//usage:#define bunzip2_full_usage "\n\n"
//usage:       "Decompress FILEs (or stdin)\n"
//usage:     "\n        -c      Write to stdout"
//usage:     "\n        -f      Force"
//usage:#define bzcat_trivial_usage
//usage:       "FILE"
//usage:#define bzcat_full_usage "\n\n"
//usage:       "Decompress to stdout"
//applet:IF_BUNZIP2(APPLET(bunzip2, BB_DIR_USR_BIN, BB_SUID_DROP))
//applet:IF_BUNZIP2(APPLET_ODDNAME(bzcat, bunzip2, BB_DIR_USR_BIN, BB_SUID_DROP, bzcat))
#if ENABLE_BUNZIP2
static
IF_DESKTOP(long long) int FAST_FUNC unpack_bunzip2(transformer_aux_data_t *aux)
{
        return unpack_bz2_stream(aux, STDIN_FILENO, STDOUT_FILENO);
}
int bunzip2_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int bunzip2_main(int argc UNUSED_PARAM, char **argv)
{
        getopt32(argv, "cfvdt");
        argv += optind;
        if (applet_name[2] == 'c') /* bzcat */
                option_mask32 |= OPT_STDOUT;

        return bbunpack(argv, unpack_bunzip2, make_new_name_generic, "bz2");
}
#endif


/*
 * Small lzma deflate implementation.
 * Copyright (C) 2006  Aurelien Jacobs <aurel@gnuage.org>
 *
 * Based on bunzip.c from busybox
 *
 * Licensed under GPLv2, see file LICENSE in this source tree.
 */

//usage:#define unlzma_trivial_usage
//usage:       "[-cf] [FILE]..."
//usage:#define unlzma_full_usage "\n\n"
//usage:       "Decompress FILE (or stdin)\n"
//usage:     "\n        -c      Write to stdout"
//usage:     "\n        -f      Force"
//usage:
//usage:#define lzma_trivial_usage
//usage:       "-d [-cf] [FILE]..."
//usage:#define lzma_full_usage "\n\n"
//usage:       "Decompress FILE (or stdin)\n"
//usage:     "\n        -d      Decompress"
//usage:     "\n        -c      Write to stdout"
//usage:     "\n        -f      Force"
//usage:
//usage:#define lzcat_trivial_usage
//usage:       "FILE"
//usage:#define lzcat_full_usage "\n\n"
//usage:       "Decompress to stdout"
//usage:
//usage:#define unxz_trivial_usage
//usage:       "[-cf] [FILE]..."
//usage:#define unxz_full_usage "\n\n"
//usage:       "Decompress FILE (or stdin)\n"
//usage:     "\n        -c      Write to stdout"
//usage:     "\n        -f      Force"
//usage:
//usage:#define xz_trivial_usage
//usage:       "-d [-cf] [FILE]..."
//usage:#define xz_full_usage "\n\n"
//usage:       "Decompress FILE (or stdin)\n"
//usage:     "\n        -d      Decompress"
//usage:     "\n        -c      Write to stdout"
//usage:     "\n        -f      Force"
//usage:
//usage:#define xzcat_trivial_usage
//usage:       "FILE"
//usage:#define xzcat_full_usage "\n\n"
//usage:       "Decompress to stdout"

#if ENABLE_UNLZMA
static
IF_DESKTOP(long long) int FAST_FUNC unpack_unlzma(transformer_aux_data_t *aux)
{
        return unpack_lzma_stream(aux, STDIN_FILENO, STDOUT_FILENO);
}
int unlzma_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int unlzma_main(int argc UNUSED_PARAM, char **argv)
{
        IF_LZMA(int opts =) getopt32(argv, "cfvdt");
# if ENABLE_LZMA
        /* lzma without -d or -t? */
        if (applet_name[2] == 'm' && !(opts & (OPT_DECOMPRESS|OPT_TEST)))
                bb_show_usage();
# endif
        /* lzcat? */
        if (applet_name[2] == 'c')
                option_mask32 |= OPT_STDOUT;

        argv += optind;
        return bbunpack(argv, unpack_unlzma, make_new_name_generic, "lzma");
}
#endif


#if ENABLE_UNXZ
static
IF_DESKTOP(long long) int FAST_FUNC unpack_unxz(transformer_aux_data_t *aux)
{
        return unpack_xz_stream(aux, STDIN_FILENO, STDOUT_FILENO);
}
int unxz_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int unxz_main(int argc UNUSED_PARAM, char **argv)
{
        IF_XZ(int opts =) getopt32(argv, "cfvdt");
# if ENABLE_XZ
        /* xz without -d or -t? */
        if (applet_name[2] == '\0' && !(opts & (OPT_DECOMPRESS|OPT_TEST)))
                bb_show_usage();
# endif
        /* xzcat? */
        if (applet_name[2] == 'c')
                option_mask32 |= OPT_STDOUT;

        argv += optind;
        return bbunpack(argv, unpack_unxz, make_new_name_generic, "xz");
}
#endif