containerd/fs/copy_linux.go

81 lines
1.9 KiB
Go

package fs
import (
"io"
"os"
"syscall"
"github.com/pkg/errors"
"github.com/stevvooe/continuity/sysx"
)
func copyFileInfo(fi os.FileInfo, name string) error {
st := fi.Sys().(*syscall.Stat_t)
if err := os.Lchown(name, int(st.Uid), int(st.Gid)); err != nil {
return errors.Wrapf(err, "failed to chown %s", name)
}
if (fi.Mode() & os.ModeSymlink) != os.ModeSymlink {
if err := os.Chmod(name, fi.Mode()); err != nil {
return errors.Wrapf(err, "failed to chmod %s", name)
}
}
if err := syscall.UtimesNano(name, []syscall.Timespec{st.Atim, st.Mtim}); err != nil {
return errors.Wrapf(err, "failed to utime %s", name)
}
return nil
}
func copyFileContent(dst, src *os.File) error {
st, err := src.Stat()
if err != nil {
return errors.Wrap(err, "unable to stat source")
}
n, err := sysx.CopyFileRange(src.Fd(), nil, dst.Fd(), nil, int(st.Size()), 0)
if err != nil {
if err != syscall.ENOSYS && err != syscall.EXDEV {
return errors.Wrap(err, "copy file range failed")
}
buf := bufferPool.Get().([]byte)
_, err = io.CopyBuffer(dst, src, buf)
bufferPool.Put(buf)
return err
}
if int64(n) != st.Size() {
return errors.Wrapf(err, "short copy: %d of %d", int64(n), st.Size())
}
return nil
}
func copyXAttrs(dst, src string) error {
xattrKeys, err := sysx.LListxattr(src)
if err != nil {
return errors.Wrapf(err, "failed to list xattrs on %s", src)
}
for _, xattr := range xattrKeys {
data, err := sysx.LGetxattr(src, xattr)
if err != nil {
return errors.Wrapf(err, "failed to get xattr %q on %s", xattr, src)
}
if err := sysx.LSetxattr(dst, xattr, data, 0); err != nil {
return errors.Wrapf(err, "failed to set xattr %q on %s", xattr, dst)
}
}
return nil
}
func copyDevice(dst string, fi os.FileInfo) error {
st, ok := fi.Sys().(*syscall.Stat_t)
if !ok {
return errors.New("unsupported stat type")
}
return syscall.Mknod(dst, uint32(fi.Mode()), int(st.Rdev))
}