/* 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  # ancient
//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