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