qemu/vmdk2raw.c

183 lines
4.4 KiB
C

/*
vmdk2raw: convert vmware images to raw disk images
Copyright (C) Net Integration Technologies 2004
Copyright (C) Matthew Chapman 2003
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <inttypes.h>
#include <sys/types.h>
#include <string.h>
#include <sys/stat.h>
#include <errno.h>
#include "vmdk.h"
#include "config-host.h"
struct cowdisk_header header;
struct cowdisk_header2 header2;
off_t disk_base, disk_limit;
unsigned int granule_size;
uint32_t l1dir[L1_SIZE];
unsigned int cached_l2dir;
uint32_t l2dir[L2_SIZE];
size_t read_physical(int fd, off64_t offset, size_t length, void *buffer)
{
size_t n;
if (lseek64(fd, offset, SEEK_SET) == -1)
{
perror("lseek");
return -1;
}
n = read(fd, buffer, length);
if (n == -1)
{
perror("read from disk");
return -1;
}
return n;
}
size_t copy_virtual(int in_fd, int out_fd, off64_t offset, void *buffer, size_t length)
{
unsigned int granule_index, granule_offset;
unsigned int l1index, l2index;
granule_index = offset / granule_size;
granule_offset = offset % granule_size;
length = MIN(length, granule_size - granule_offset);
length = MIN(length, disk_limit - offset);
l1index = (granule_index >> L2_BITS) & L1_MASK;
l2index = granule_index & L2_MASK;
if (l1dir[l1index] == 0)
goto zero_fill;
if (l1index != cached_l2dir)
{
if (read_physical(in_fd, (l1dir[l1index] << SECTOR_BITS), sizeof(l2dir), (char *)l2dir) != sizeof(l2dir))
return 0;
cached_l2dir = l1index;
}
if (l2dir[l2index] == 0)
goto zero_fill;
if (read_physical(in_fd, (l2dir[l2index] << SECTOR_BITS) + granule_offset, length, buffer) != length)
return 0;
write(out_fd, buffer, length);
return length;
zero_fill:
/* the last chunk of the file can not be sparse
* or the file will be truncated */
if (offset + length < disk_limit) {
memset(buffer, 0, length);
write(out_fd, buffer, length);
} else {
if (lseek(out_fd, length, SEEK_CUR) == (off_t)-1)
perror("lseek");
}
return length;
}
int open_vmdk(const char *filename)
{
int fd = open(filename, O_RDONLY | O_LARGEFILE);
if (fd == -1)
{
perror(filename);
return -1;
}
if (read(fd, &header, sizeof(header)) != sizeof(header))
{
perror("read from disk");
return -1;
}
if (memcmp(header.magic, "COWD", 4) != 0)
{
fprintf(stderr, "%s is not a VMware virtual disk image\n", filename);
return -1;
}
granule_size = header.granularity << SECTOR_BITS;
if (read_physical(fd, header.l1dir_sector << SECTOR_BITS, sizeof(l1dir), (char *)l1dir) != sizeof(l1dir))
return -1;
disk_limit = header.disk_sectors << SECTOR_BITS;
cached_l2dir = -1;
return fd;
}
void help(void)
{
printf("vmdk2raw\n"
"usage: vmdk2raw vmware_image output_image\n"
"\n"
"vmware_image a vmware 2.x/3.x cow image\n"
"output_image the created disk image\n"
);
exit(1);
}
#define BUF_SIZE granule_size
void copy_disk(in_fd, out_fd)
{
char buf[BUF_SIZE];
off64_t i = 0;
while (i < disk_limit) {
i += copy_virtual(in_fd, out_fd, i, buf, sizeof(buf));
}
}
int main(int argc, char **argv)
{
int out_fd, in_fd;
if (argc < 3)
help();
in_fd = open_vmdk(argv[1]);
if (in_fd < 0) {
return -1;
}
out_fd = open(argv[2], O_WRONLY | O_CREAT | O_TRUNC, S_IRUSR | S_IWUSR);
if (out_fd < 0) {
perror(argv[2]);
return -1;
}
copy_disk(in_fd, out_fd);
close(out_fd);
return 0;
}