/*-

 * Copyright (c) 2003-2009 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_support_format_raw.c 201107 2009-12-28 03:25:33Z kientzle $");

#ifdef HAVE_ERRNO_H

#include <errno.h>

#endif

#include <stdio.h>

#ifdef HAVE_STDLIB_H

#include <stdlib.h>

#endif

#include "archive.h"

#include "archive_entry.h"

#include "archive_private.h"

#include "archive_read_private.h"

struct raw_info {

	int64_t offset; /* Current position in the file. */

	int64_t unconsumed;

	int     end_of_file;

};

static int	archive_read_format_raw_bid(struct archive_read *, int);

static int	archive_read_format_raw_cleanup(struct archive_read *);

static int	archive_read_format_raw_read_data(struct archive_read *,

		    const void **, size_t *, int64_t *);

static int	archive_read_format_raw_read_data_skip(struct archive_read *);

static int	archive_read_format_raw_read_header(struct archive_read *,

		    struct archive_entry *);

int

archive_read_support_format_raw(struct archive *_a)

{

	struct raw_info *info;

	struct archive_read *a = (struct archive_read *)_a;

	int r;

	archive_check_magic(_a, ARCHIVE_READ_MAGIC,

	    ARCHIVE_STATE_NEW, "archive_read_support_format_raw");

	info = (struct raw_info *)calloc(1, sizeof(*info));

	if (info == NULL) {

		archive_set_error(&a->archive, ENOMEM,

		    "Can't allocate raw_info data");

		return (ARCHIVE_FATAL);

	}

	r = __archive_read_register_format(a,

	    info,

	    "raw",

	    archive_read_format_raw_bid,

	    NULL,

	    archive_read_format_raw_read_header,

	    archive_read_format_raw_read_data,

	    archive_read_format_raw_read_data_skip,

	    NULL,

	    archive_read_format_raw_cleanup,

	    NULL,

	    NULL);

	if (r != ARCHIVE_OK)

		free(info);

	return (r);

}

/*

 * Bid 1 if this is a non-empty file.  Anyone who can really support

 * this should outbid us, so it should generally be safe to use "raw"

 * in conjunction with other formats.  But, this could really confuse

 * folks if there are bid errors or minor file damage, so we don't

 * include "raw" as part of support_format_all().

 */

static int

archive_read_format_raw_bid(struct archive_read *a, int best_bid)

{

	if (best_bid < 1 && __archive_read_ahead(a, 1, NULL) != NULL)

		return (1);

	return (-1);

}

/*

 * Mock up a fake header.

 */

static int

archive_read_format_raw_read_header(struct archive_read *a,

    struct archive_entry *entry)

{

	struct raw_info *info;

	info = (struct raw_info *)(a->format->data);

	if (info->end_of_file)

		return (ARCHIVE_EOF);

	a->archive.archive_format = ARCHIVE_FORMAT_RAW;

	a->archive.archive_format_name = "raw";

	archive_entry_set_pathname(entry, "data");

	archive_entry_set_filetype(entry, AE_IFREG);

	archive_entry_set_perm(entry, 0644);

	/* I'm deliberately leaving most fields unset here. */

	return (ARCHIVE_OK);

}

static int

archive_read_format_raw_read_data(struct archive_read *a,

    const void **buff, size_t *size, int64_t *offset)

{

	struct raw_info *info;

	ssize_t avail;

	info = (struct raw_info *)(a->format->data);

	/* Consume the bytes we read last time. */

	if (info->unconsumed) {

		__archive_read_consume(a, info->unconsumed);

		info->unconsumed = 0;

	}

	if (info->end_of_file)

		return (ARCHIVE_EOF);

	/* Get whatever bytes are immediately available. */

	*buff = __archive_read_ahead(a, 1, &avail);

	if (avail > 0) {

		/* Return the bytes we just read */

		*size = avail;

		*offset = info->offset;

		info->offset += *size;

		info->unconsumed = avail;

		return (ARCHIVE_OK);

	} else if (0 == avail) {

		/* Record and return end-of-file. */

		info->end_of_file = 1;

		*size = 0;

		*offset = info->offset;

		return (ARCHIVE_EOF);

	} else {

		/* Record and return an error. */

		*size = 0;

		*offset = info->offset;

		return ((int)avail);

	}

}

static int

archive_read_format_raw_read_data_skip(struct archive_read *a)

{

	struct raw_info *info = (struct raw_info *)(a->format->data);

	/* Consume the bytes we read last time. */

	if (info->unconsumed) {

		__archive_read_consume(a, info->unconsumed);

		info->unconsumed = 0;

	}

	info->end_of_file = 1;

	return (ARCHIVE_OK);

}

static int

archive_read_format_raw_cleanup(struct archive_read *a)

{

	struct raw_info *info;

	info = (struct raw_info *)(a->format->data);

	free(info);

	a->format->data = NULL;

	return (ARCHIVE_OK);

}