1
0
Fork 0
mirror of https://github.com/moby/moby.git synced 2022-11-09 12:21:53 -05:00
moby--moby/reflink_copy_linux.go
2014-01-31 03:16:42 -07:00

55 lines
961 B
Go

// +build amd64
package docker
// FIXME: This could be easily rewritten in pure Go
/*
#include <sys/ioctl.h>
#include <linux/fs.h>
#include <errno.h>
// See linux.git/fs/btrfs/ioctl.h
#define BTRFS_IOCTL_MAGIC 0x94
#define BTRFS_IOC_CLONE _IOW(BTRFS_IOCTL_MAGIC, 9, int)
int
btrfs_reflink(int fd_out, int fd_in)
{
int res;
res = ioctl(fd_out, BTRFS_IOC_CLONE, fd_in);
if (res < 0)
return errno;
return 0;
}
*/
import "C"
import (
"io"
"os"
"syscall"
)
// FIXME: Move this to btrfs package?
func BtrfsReflink(fd_out, fd_in uintptr) error {
res := C.btrfs_reflink(C.int(fd_out), C.int(fd_in))
if res != 0 {
return syscall.Errno(res)
}
return nil
}
func CopyFile(dstFile, srcFile *os.File) error {
err := BtrfsReflink(dstFile.Fd(), srcFile.Fd())
if err == nil {
return nil
}
// Fall back to normal copy
// FIXME: Check the return of Copy and compare with dstFile.Stat().Size
_, err = io.Copy(dstFile, srcFile)
return err
}