freebsd-dev/lib/libarchive/archive_read_data_into_fd.c
Tim Kientzle c3b11d8213 Correctly handle writing very large blocks (>1M) through to a disk
file.  This doesn't happen in normal use, because the file I/O and
decompression layers only pass through smaller blocks.  It can happen
with custom read functions that block I/O in larger blocks.
2006-11-12 23:45:40 +00:00

93 lines
2.8 KiB
C

/*-
* Copyright (c) 2003-2004 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
* 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 "archive_platform.h"
__FBSDID("$FreeBSD$");
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include "archive.h"
#include "archive_private.h"
/* Maximum amount of data to write at one time. */
#define MAX_WRITE (1024 * 1024)
/*
* This implementation minimizes copying of data and is sparse-file aware.
*/
int
archive_read_data_into_fd(struct archive *a, int fd)
{
int r;
const void *buff;
size_t size;
ssize_t bytes_to_write, bytes_written, total_written;
off_t offset;
off_t output_offset;
__archive_check_magic(a, ARCHIVE_READ_MAGIC, ARCHIVE_STATE_DATA, "archive_read_data_into_fd");
total_written = 0;
output_offset = 0;
while ((r = archive_read_data_block(a, &buff, &size, &offset)) ==
ARCHIVE_OK) {
const char *p = buff;
if (offset > output_offset) {
lseek(fd, offset - output_offset, SEEK_CUR);
output_offset = offset;
}
while (size > 0) {
bytes_to_write = size;
if (bytes_to_write > MAX_WRITE)
bytes_to_write = MAX_WRITE;
bytes_written = write(fd, p, bytes_to_write);
if (bytes_written < 0) {
archive_set_error(a, errno, "Write error");
return (-1);
}
output_offset += bytes_written;
total_written += bytes_written;
p += bytes_written;
size -= bytes_written;
if (a->extract_progress != NULL)
(*a->extract_progress)(a->extract_progress_user_data);
}
}
if (r != ARCHIVE_EOF)
return (r);
return (ARCHIVE_OK);
}