/*-

 * Copyright (c) 2003-2007 Tim Kientzle

 * 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.

 * 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 "archive_platform.h"

__FBSDID("$FreeBSD: head/lib/libarchive/archive_read_open_file.c 201093 2009-12-28 02:28:44Z kientzle $");

#ifdef HAVE_SYS_STAT_H

#include <sys/stat.h>

#endif

#ifdef HAVE_ERRNO_H

#include <errno.h>

#endif

#ifdef HAVE_FCNTL_H

#include <fcntl.h>

#endif

#ifdef HAVE_IO_H

#include <io.h>

#endif

#ifdef HAVE_STDLIB_H

#include <stdlib.h>

#endif

#ifdef HAVE_STRING_H

#include <string.h>

#endif

#ifdef HAVE_UNISTD_H

#include <unistd.h>

#endif

#include "archive.h"

struct read_FILE_data {

	FILE    *f;

	size_t	 block_size;

	void	*buffer;

	char	 can_skip;

};

static int	file_close(struct archive *, void *);

static ssize_t	file_read(struct archive *, void *, const void **buff);

static int64_t	file_skip(struct archive *, void *, int64_t request);

int

archive_read_open_FILE(struct archive *a, FILE *f)

{

	struct stat st;

	struct read_FILE_data *mine;

	size_t block_size = 128 * 1024;

	void *b;

	archive_clear_error(a);

	mine = (struct read_FILE_data *)malloc(sizeof(*mine));

	b = malloc(block_size);

	if (mine == NULL || b == NULL) {

		archive_set_error(a, ENOMEM, "No memory");

		free(mine);

		free(b);

		return (ARCHIVE_FATAL);

	}

	mine->block_size = block_size;

	mine->buffer = b;

	mine->f = f;

	/*

	 * If we can't fstat() the file, it may just be that it's not

	 * a file.  (On some platforms, FILE * objects can wrap I/O

	 * streams that don't support fileno()).  As a result, fileno()

	 * should be used cautiously.)

	 */

	if (fstat(fileno(mine->f), &st) == 0 && S_ISREG(st.st_mode)) {

		archive_read_extract_set_skip_file(a, st.st_dev, st.st_ino);

		/* Enable the seek optimization only for regular files. */

		mine->can_skip = 1;

	} else

		mine->can_skip = 0;

#if defined(__CYGWIN__) || defined(_WIN32)

	setmode(fileno(mine->f), O_BINARY);

#endif

	archive_read_set_read_callback(a, file_read);

	archive_read_set_skip_callback(a, file_skip);

	archive_read_set_close_callback(a, file_close);

	archive_read_set_callback_data(a, mine);

	return (archive_read_open1(a));

}

static ssize_t

file_read(struct archive *a, void *client_data, const void **buff)

{

	struct read_FILE_data *mine = (struct read_FILE_data *)client_data;

	size_t bytes_read;

	*buff = mine->buffer;

	bytes_read = fread(mine->buffer, 1, mine->block_size, mine->f);

	if (bytes_read < mine->block_size && ferror(mine->f)) {

		archive_set_error(a, errno, "Error reading file");

	}

	return (bytes_read);

}

static int64_t

file_skip(struct archive *a, void *client_data, int64_t request)

{

	struct read_FILE_data *mine = (struct read_FILE_data *)client_data;

#if HAVE_FSEEKO

	off_t skip = (off_t)request;

#elif HAVE__FSEEKI64

	int64_t skip = request;

#else

	long skip = (long)request;

#endif

	int skip_bits = sizeof(skip) * 8 - 1;

	(void)a; /* UNUSED */

	/*

	 * If we can't skip, return 0 as the amount we did step and

	 * the caller will work around by reading and discarding.

	 */

	if (!mine->can_skip)

		return (0);

	if (request == 0)

		return (0);

	/* If request is too big for a long or an off_t, reduce it. */

	if (sizeof(request) > sizeof(skip)) {

		int64_t max_skip =

		    (((int64_t)1 << (skip_bits - 1)) - 1) * 2 + 1;

		if (request > max_skip)

			skip = max_skip;

	}

#ifdef __ANDROID__

        /* fileno() isn't safe on all platforms ... see above. */

	if (lseek(fileno(mine->f), skip, SEEK_CUR) < 0)

#elif HAVE_FSEEKO

	if (fseeko(mine->f, skip, SEEK_CUR) != 0)

#elif HAVE__FSEEKI64

	if (_fseeki64(mine->f, skip, SEEK_CUR) != 0)

#else

	if (fseek(mine->f, skip, SEEK_CUR) != 0)

#endif

	{

		mine->can_skip = 0;

		return (0);

	}

	return (request);

}

static int

file_close(struct archive *a, void *client_data)

{

	struct read_FILE_data *mine = (struct read_FILE_data *)client_data;

	(void)a; /* UNUSED */

	if (mine->buffer != NULL)

		free(mine->buffer);

	free(mine);

	return (ARCHIVE_OK);

}