/*-

 * Copyright (c) 2008 Jaakko Heinonen

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer

 *    in this position and unchanged.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR

 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES

 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.

 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,

 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT

 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF

 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

#include <sys/cdefs.h>

#ifdef __FBSDID

__FBSDID("$FreeBSD$");

#endif

#include <sys/stat.h>

#include <sys/types.h>

#include <archive.h>

#include <archive_entry.h>

#include <assert.h>

#include <err.h>

#include <errno.h>

#include <fcntl.h>

#include <limits.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <sysexits.h>

#include <unistd.h>

#include "tree.h"

/* command line options */

static int	b_opt;	/* use alternative shar binary format */

static int	r_opt;	/* recurse into subdirectories */

static char	*o_arg;	/* output file name */

static void

usage(void)

{

	fprintf(stderr, "Usage: shar [-br] [-o filename] file ...\n");

	exit(EX_USAGE);

}

/*

 * Initialize archive structure and create a shar archive.

 */

static struct archive *

shar_create(void)

{

	struct archive *a;

	if ((a = archive_write_new()) == NULL)

		errx(EXIT_FAILURE, "%s", archive_error_string(a));

	if (b_opt)

		archive_write_set_format_shar_dump(a);

	else

		archive_write_set_format_shar(a);

	archive_write_set_compression_none(a);

	if (archive_write_open_filename(a, o_arg) != ARCHIVE_OK)

		errx(EX_CANTCREAT, "%s", archive_error_string(a));

	return (a);

}

/* buffer for file data */

static char buffer[32768];

/*

 * Write file data to an archive entry.

 */

static int

shar_write_entry_data(struct archive *a, const int fd)

{

	ssize_t bytes_read, bytes_written;

	assert(a != NULL);

	assert(fd >= 0);

	bytes_read = read(fd, buffer, sizeof(buffer));

	while (bytes_read != 0) {

		if (bytes_read < 0) {

			archive_set_error(a, errno, "Read failed");

			return (ARCHIVE_WARN);

		}

		bytes_written = archive_write_data(a, buffer, bytes_read);

		if (bytes_written < 0)

			return (ARCHIVE_WARN);

		bytes_read = read(fd, buffer, sizeof(buffer));

	}

	return (ARCHIVE_OK);

}

/*

 * Write a file to the archive. We have special handling for symbolic links.

 */

static int

shar_write_entry(struct archive *a, const char *pathname, const char *accpath,

    const struct stat *st)

{

	struct archive_entry *entry;

	int fd = -1;

	int ret = ARCHIVE_OK;

	assert(a != NULL);

	assert(pathname != NULL);

	assert(accpath != NULL);

	assert(st != NULL);

	entry = archive_entry_new();

	if (S_ISREG(st->st_mode) && st->st_size > 0) {

		/* regular file */

		if ((fd = open(accpath, O_RDONLY)) == -1) {

			warn("%s", accpath);

			ret = ARCHIVE_WARN;

			goto out;

		}

	} else if (S_ISLNK(st->st_mode)) {

		/* symbolic link */

		char lnkbuff[PATH_MAX + 1];

		int lnklen;

		if ((lnklen = readlink(accpath, lnkbuff, PATH_MAX)) == -1) {

			warn("%s", accpath);

			ret = ARCHIVE_WARN;

			goto out;

		}

		lnkbuff[lnklen] = '\0';

		archive_entry_set_symlink(entry, lnkbuff);

	}

	archive_entry_copy_stat(entry, st);

	archive_entry_set_pathname(entry, pathname);

	if (!S_ISREG(st->st_mode) || st->st_size == 0)

		archive_entry_set_size(entry, 0);

	if (archive_write_header(a, entry) != ARCHIVE_OK) {

		warnx("%s: %s", pathname, archive_error_string(a));

		ret = ARCHIVE_WARN;

		goto out;

	}

	if (fd >= 0) {

		if ((ret = shar_write_entry_data(a, fd)) != ARCHIVE_OK)

			warnx("%s: %s", accpath, archive_error_string(a));

	}

out:

	archive_entry_free(entry);

	if (fd >= 0)

		close(fd);

	return (ret);

}

/*

 * Write singe path to the archive. The path can be a regular file, directory

 * or device. Symbolic links are followed.

 */

static int

shar_write_path(struct archive *a, const char *pathname)

{

	struct stat st;

	assert(a != NULL);

	assert(pathname != NULL);

	if ((stat(pathname, &st)) == -1) {

		warn("%s", pathname);

		return (ARCHIVE_WARN);

	}

	return (shar_write_entry(a, pathname, pathname, &st);;

}

/*

 * Write tree to the archive. If pathname is a symbolic link it will be

 * followed. Other symbolic links are stored as such to the archive.

 */

static int

shar_write_tree(struct archive *a, const char *pathname)

{

	struct tree *t;

	const struct stat *lst, *st;

	int error = 0;

	int tree_ret;

	int first;

	assert(a != NULL);

	assert(pathname != NULL);

	t = tree_open(pathname);

	for (first = 1; (tree_ret = tree_next(t)); first = 0) {

		if (tree_ret == TREE_ERROR_DIR) {

			warnx("%s: %s", tree_current_path(t),

			    strerror(tree_errno(t)));

			error = 1;

			continue;

		} else if (tree_ret != TREE_REGULAR)

			continue;

		if ((lst = tree_current_lstat(t)) == NULL) {

			warn("%s", tree_current_path(t));

			error = 1;

			continue;

		}

		/*

		 * If the symlink was given on command line then

		 * follow it rather than write it as symlink.

		 */

		if (first && S_ISLNK(lst->st_mode)) {

			if ((st = tree_current_stat(t)) == NULL) {

				warn("%s", tree_current_path(t));

				error = 1;

				continue;

			}

		} else

			st = lst;

		if (shar_write_entry(a, tree_current_path(t),

		    tree_current_access_path(t), st) != ARCHIVE_OK)

			error = 1;

		tree_descend(t);

	}

	tree_close(t);

	return ((error != 0) ? ARCHIVE_WARN : ARCHIVE_OK);

}

/*

 * Create a shar archive and write files/trees into it.

 */

static int

shar_write(char **fn, size_t nfn)

{

	struct archive *a;

	size_t i;

	int error = 0;

	assert(fn != NULL);

	assert(nfn > 0);

	a = shar_create();

	for (i = 0; i < nfn; i++) {

		if (r_opt) {

			if (shar_write_tree(a, fn[i]) !=  ARCHIVE_OK)

				error = 1;

		} else {

			if (shar_write_path(a, fn[i]) != ARCHIVE_OK)

				error = 1;

		}

	}

	if (archive_write_free(a) != ARCHIVE_OK)

		errx(EXIT_FAILURE, "%s", archive_error_string(a));

	if (error != 0)

		warnx("Error exit delayed from previous errors.");

	return (error);

}

int

main(int argc, char **argv)

{

	int opt;

	while ((opt = getopt(argc, argv, "bro:")) != -1) {

		switch (opt) {

		case 'b':

			b_opt = 1;

			break;

		case 'o':

			o_arg = optarg;

			break;

		case 'r':

			r_opt = 1;

			break;

		default:

			usage();

			/* NOTREACHED */

		}

	}

	argc -= optind;

	argv += optind;

	if(argc < 1)

		usage();

	if (shar_write(argv, argc) != 0)

		exit(EXIT_FAILURE);

	else

		exit(EXIT_SUCCESS);

	/* NOTREACHED */

}