forked from qiniubs/docker
/
diff.go
47 lines (42 loc) · 885 Bytes
/
diff.go
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package chrootarchive
import (
"flag"
"fmt"
"io/ioutil"
"os"
"runtime"
"syscall"
"github.com/docker/docker/pkg/archive"
"github.com/docker/docker/pkg/reexec"
)
func applyLayer() {
runtime.LockOSThread()
flag.Parse()
if err := syscall.Chroot(flag.Arg(0)); err != nil {
fatal(err)
}
if err := syscall.Chdir("/"); err != nil {
fatal(err)
}
tmpDir, err := ioutil.TempDir("/", "temp-docker-extract")
if err != nil {
fatal(err)
}
os.Setenv("TMPDIR", tmpDir)
if err := archive.ApplyLayer("/", os.Stdin); err != nil {
os.RemoveAll(tmpDir)
fatal(err)
}
os.RemoveAll(tmpDir)
flush(os.Stdin)
os.Exit(0)
}
func ApplyLayer(dest string, layer archive.ArchiveReader) error {
cmd := reexec.Command("docker-applyLayer", dest)
cmd.Stdin = layer
out, err := cmd.CombinedOutput()
if err != nil {
return fmt.Errorf("ApplyLayer %s %s", err, out)
}
return nil
}