/* 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"

/* lzop_main() uses bbunpack(), need this: */
//kbuild:lib-$(CONFIG_LZOP) += bbunzip.o

/* Note: must be kept in sync with archival/lzop.c */
enum {
        OPT_STDOUT     = 1 << 0,
        OPT_FORCE      = 1 << 1,
        /* only some decompressors: */
        OPT_VERBOSE    = 1 << 2,
        OPT_QUIET      = 1 << 3,
        OPT_DECOMPRESS = 1 << 4,
        OPT_TEST       = 1 << 5,
        SEAMLESS_MAGIC = (1 << 31) * SEAMLESS_COMPRESSION,
};

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_state_t *xstate),
        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 = 0;
        char *filename, *new_name;
        smallint exitcode = 0;
        transformer_state_t xstate;

        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 (!(option_mask32 & SEAMLESS_MAGIC)) {
                                if (stat(filename, &stat_buf) != 0) {
 err_name:
                                        bb_simple_perror_msg(filename);
 err:
                                        exitcode = 1;
                                        goto free_name;
                                }
                                if (open_to_or_warn(STDIN_FILENO, filename, O_RDONLY, 0))
                                        goto err;
                        } else {
                                /* "clever zcat" with FILE */
                                /* fail_if_not_compressed because zcat refuses uncompressed input */
                                int fd = open_zipped(filename, /*fail_if_not_compressed:*/ 1);
                                if (fd < 0)
                                        goto err_name;
                                xmove_fd(fd, STDIN_FILENO);
                        }
                } else
                if (option_mask32 & SEAMLESS_MAGIC) {
                        /* "clever zcat" on stdin */
                        if (setup_unzip_on_fd(STDIN_FILENO, /*fail_if_not_compressed*/ 1))
                                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))
                                        xfunc_die();
                        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 (!(option_mask32 & OPT_FORCE) && isatty(STDIN_FILENO)) {
                        bb_error_msg_and_die("compressed data not read from terminal, "
                                        "use -f to force it");
                }

                if (!(option_mask32 & SEAMLESS_MAGIC)) {
                        init_transformer_state(&xstate);
                        xstate.check_signature = 1;
                        /*xstate.src_fd = STDIN_FILENO; - already is */
                        xstate.dst_fd = STDOUT_FILENO;
                        status = unpacker(&xstate);
                        if (status < 0)
                                exitcode = 1;
                } else {
                        if (bb_copyfd_eof(STDIN_FILENO, STDOUT_FILENO) < 0)
                                /* Disk full, tty closed, etc. No point in continuing */
                                xfunc_die();
                }

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

                if (filename) {
                        char *del = new_name;

                        if (status >= 0) {
                                unsigned new_name_len;

                                /* TODO: restore other things? */
                                if (xstate.mtime != 0) {
                                        struct timeval times[2];

                                        times[1].tv_sec = times[0].tv_sec = xstate.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 */
                                }

                                if (ENABLE_DESKTOP)
                                        new_name_len = strlen(new_name);
                                /* Restore source filename (unless tgz -> tar case) */
                                if (new_name == filename) {
                                        new_name_len = strlen(filename);
                                        filename[new_name_len] = '.';
                                }
                                /* Extreme bloat for gunzip compat */
                                /* Some users do want this info... */
                                if (ENABLE_DESKTOP && (option_mask32 & OPT_VERBOSE)) {
                                        unsigned percent = status
                                                ? ((uoff_t)stat_buf.st_size * 100u / (unsigned long long)status)
                                                : 0;
                                        fprintf(stderr, "%s: %u%% - replaced with %.*s\n",
                                                filename,
                                                100u - percent,
                                                new_name_len, new_name
                                        );
                                }
                                /* Delete _source_ file */
                                del = filename;
                        }
                        xunlink(del);
 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"

//config:config UNCOMPRESS
//config:       bool "uncompress"
//config:       default n
//config:       help
//config:         uncompress is used to decompress archives created by compress.
//config:         Not much used anymore, replaced by gzip/gunzip.

//applet:IF_UNCOMPRESS(APPLET(uncompress, BB_DIR_BIN, BB_SUID_DROP))
//kbuild:lib-$(CONFIG_UNCOMPRESS) += bbunzip.o
#if ENABLE_UNCOMPRESS
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_Z_stream, 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.
 */
//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"

//config:config GUNZIP
//config:       bool "gunzip"
//config:       default y
//config:       help
//config:         gunzip is used to decompress archives created by gzip.
//config:         You can use the `-t' option to test the integrity of
//config:         an archive, without decompressing it.

//applet:IF_GUNZIP(APPLET(gunzip, BB_DIR_BIN, BB_SUID_DROP))
//applet:IF_GUNZIP(APPLET_ODDNAME(zcat, gunzip, BB_DIR_BIN, BB_SUID_DROP, zcat))
//kbuild:lib-$(CONFIG_GZIP) += bbunzip.o
//kbuild:lib-$(CONFIG_GUNZIP) += bbunzip.o
#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;
}
/*
 * 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, "cfvqdtn");
        argv += optind;

        /* If called as zcat...
         * Normally, "zcat" is just "gunzip -c".
         * But if seamless magic is enabled, then we are much more clever.
         */
        if (applet_name[1] == 'c')
                option_mask32 |= OPT_STDOUT | SEAMLESS_MAGIC;

        return bbunpack(argv, unpack_gz_stream, 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"

//config:config BUNZIP2
//config:       bool "bunzip2"
//config:       default y
//config:       help
//config:         bunzip2 is a compression utility using the Burrows-Wheeler block
//config:         sorting text compression algorithm, and Huffman coding. Compression
//config:         is generally considerably better than that achieved by more
//config:         conventional LZ77/LZ78-based compressors, and approaches the
//config:         performance of the PPM family of statistical compressors.
//config:
//config:         Unless you have a specific application which requires bunzip2, you
//config:         should probably say N here.

//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))
//kbuild:lib-$(CONFIG_BZIP2) += bbunzip.o
//kbuild:lib-$(CONFIG_BUNZIP2) += bbunzip.o
#if ENABLE_BUNZIP2
int bunzip2_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int bunzip2_main(int argc UNUSED_PARAM, char **argv)
{
        getopt32(argv, "cfvqdt");
        argv += optind;
        if (applet_name[2] == 'c') /* bzcat */
                option_mask32 |= OPT_STDOUT;

        return bbunpack(argv, unpack_bz2_stream, 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"

//config:config UNLZMA
//config:       bool "unlzma"
//config:       default y
//config:       help
//config:         unlzma is a compression utility using the Lempel-Ziv-Markov chain
//config:         compression algorithm, and range coding. Compression
//config:         is generally considerably better than that achieved by the bzip2
//config:         compressors.
//config:
//config:         The BusyBox unlzma applet is limited to decompression only.
//config:         On an x86 system, this applet adds about 4K.
//config:
//config:config FEATURE_LZMA_FAST
//config:       bool "Optimize unlzma for speed"
//config:       default n
//config:       depends on UNLZMA
//config:       help
//config:         This option reduces decompression time by about 25% at the cost of
//config:         a 1K bigger binary.
//config:
//config:config LZMA
//config:       bool "Provide lzma alias which supports only unpacking"
//config:       default y
//config:       depends on UNLZMA
//config:       help
//config:         Enable this option if you want commands like "lzma -d" to work.
//config:         IOW: you'll get lzma applet, but it will always require -d option.

//applet:IF_UNLZMA(APPLET(unlzma, BB_DIR_USR_BIN, BB_SUID_DROP))
//applet:IF_UNLZMA(APPLET_ODDNAME(lzcat, unlzma, BB_DIR_USR_BIN, BB_SUID_DROP, lzcat))
//applet:IF_LZMA(APPLET_ODDNAME(lzma, unlzma, BB_DIR_USR_BIN, BB_SUID_DROP, lzma))
//kbuild:lib-$(CONFIG_UNLZMA) += bbunzip.o
#if ENABLE_UNLZMA
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, "cfvqdt");
# 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_lzma_stream, make_new_name_generic, "lzma");
}
#endif


//config:config UNXZ
//config:       bool "unxz"
//config:       default y
//config:       help
//config:         unxz is a unlzma successor.
//config:
//config:config XZ
//config:       bool "Provide xz alias which supports only unpacking"
//config:       default y
//config:       depends on UNXZ
//config:       help
//config:         Enable this option if you want commands like "xz -d" to work.
//config:         IOW: you'll get xz applet, but it will always require -d option.

//applet:IF_UNXZ(APPLET(unxz, BB_DIR_USR_BIN, BB_SUID_DROP))
//applet:IF_UNXZ(APPLET_ODDNAME(xzcat, unxz, BB_DIR_USR_BIN, BB_SUID_DROP, xzcat))
//applet:IF_XZ(APPLET_ODDNAME(xz, unxz, BB_DIR_USR_BIN, BB_SUID_DROP, xz))
//kbuild:lib-$(CONFIG_UNXZ) += bbunzip.o
#if ENABLE_UNXZ
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, "cfvqdt");
# 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_xz_stream, make_new_name_generic, "xz");
}
#endif