freebsd-dev/lib/libarchive/archive_read_support_format_raw.c

186 lines
5.3 KiB
C

/*-
* 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("$FreeBSD$");
#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. */
int end_of_file;
};
static int archive_read_format_raw_bid(struct archive_read *);
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 *, off_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;
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,
archive_read_format_raw_cleanup);
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)
{
if (__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 data";
archive_entry_set_pathname(entry, "data");
/* XXX should we set mode to mimic a regular file? XXX */
/* 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, off_t *offset)
{
struct raw_info *info;
ssize_t avail;
info = (struct raw_info *)(a->format->data);
if (info->end_of_file)
return (ARCHIVE_EOF);
/* Get whatever bytes are immediately available. */
*buff = __archive_read_ahead(a, 1, &avail);
if (avail > 0) {
/* Consume and return the bytes we just read */
__archive_read_consume(a, avail);
*size = avail;
*offset = info->offset;
info->offset += *size;
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 (avail);
}
}
static int
archive_read_format_raw_read_data_skip(struct archive_read *a)
{
struct raw_info *info;
off_t bytes_skipped;
int64_t request = 1024 * 1024 * 1024UL; /* Skip 1 GB at a time. */
info = (struct raw_info *)(a->format->data);
if (info->end_of_file)
return (ARCHIVE_EOF);
info->end_of_file = 1;
for (;;) {
bytes_skipped = __archive_read_skip_lenient(a, request);
if (bytes_skipped < 0)
return (ARCHIVE_FATAL);
if (bytes_skipped < request)
return (ARCHIVE_OK);
/* We skipped all the bytes we asked for. There might
* be more, so try again. */
}
}
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);
}