func createPidFile(path string, process *libcontainer.Process) error {
pid, err := process.Pid()
if err != nil {
return err
}
f, err := os.Create(path)
if err != nil {
return err
}
defer f.Close()
_, err = fmt.Fprintf(f, "%d", pid)
return err
}
func createPidFile(path string, process *libcontainer.Process) error {
pid, err := process.Pid()
if err != nil {
return err
}
f, err := os.OpenFile(path, os.O_RDWR|os.O_CREATE|os.O_EXCL, 0666)
if err != nil {
return err
}
defer f.Close()
_, err = fmt.Fprintf(f, "%d", pid)
return err
}
// createPidFile creates a file with the processes pid inside it atomically
// it creates a temp file with the paths filename + '.' infront of it
// then renames the file
func createPidFile(path string, process *libcontainer.Process) error {
pid, err := process.Pid()
if err != nil {
return err
}
var (
tmpDir = filepath.Dir(path)
tmpName = filepath.Join(tmpDir, fmt.Sprintf(".%s", filepath.Base(path)))
)
f, err := os.OpenFile(tmpName, os.O_RDWR|os.O_CREATE|os.O_EXCL|os.O_SYNC, 0666)
if err != nil {
return err
}
_, err = fmt.Fprintf(f, "%d", pid)
f.Close()
if err != nil {
return err
}
return os.Rename(tmpName, path)
}
func waitInPIDHost(p *libcontainer.Process, c libcontainer.Container) func() (*os.ProcessState, error) {
return func() (*os.ProcessState, error) {
pid, err := p.Pid()
if err != nil {
return nil, err
}
process, err := os.FindProcess(pid)
s, err := process.Wait()
if err != nil {
execErr, ok := err.(*exec.ExitError)
if !ok {
return s, err
}
s = execErr.ProcessState
}
killCgroupProcs(c)
p.Wait()
return s, err
}
}
// forward handles the main signal event loop forwarding, resizing, or reaping depending
// on the signal received.
func (h *signalHandler) forward(process *libcontainer.Process) (int, error) {
// make sure we know the pid of our main process so that we can return
// after it dies.
pid1, err := process.Pid()
if err != nil {
return -1, err
}
// perform the initial tty resize.
h.tty.resize()
for s := range h.signals {
switch s {
case syscall.SIGWINCH:
h.tty.resize()
case syscall.SIGCHLD:
exits, err := h.reap()
if err != nil {
logrus.Error(err)
}
for _, e := range exits {
logrus.WithFields(logrus.Fields{
"pid": e.pid,
"status": e.status,
}).Debug("process exited")
if e.pid == pid1 {
// call Wait() on the process even though we already have the exit
// status because we must ensure that any of the go specific process
// fun such as flushing pipes are complete before we return.
process.Wait()
return e.status, nil
}
}
default:
logrus.Debugf("sending signal to process %s", s)
if err := syscall.Kill(pid1, s.(syscall.Signal)); err != nil {
logrus.Error(err)
}
}
}
return -1, nil
}
func TestEnter(t *testing.T) {
if testing.Short() {
return
}
root, err := newTestRoot()
ok(t, err)
defer os.RemoveAll(root)
rootfs, err := newRootfs()
ok(t, err)
defer remove(rootfs)
config := newTemplateConfig(rootfs)
container, err := factory.Create("test", config)
ok(t, err)
defer container.Destroy()
// Execute a first process in the container
stdinR, stdinW, err := os.Pipe()
ok(t, err)
var stdout, stdout2 bytes.Buffer
pconfig := libcontainer.Process{
Args: []string{"sh", "-c", "cat && readlink /proc/self/ns/pid"},
Env: standardEnvironment,
Stdin: stdinR,
Stdout: &stdout,
}
err = container.Start(&pconfig)
stdinR.Close()
defer stdinW.Close()
ok(t, err)
pid, err := pconfig.Pid()
ok(t, err)
// Execute another process in the container
stdinR2, stdinW2, err := os.Pipe()
ok(t, err)
pconfig2 := libcontainer.Process{
Env: standardEnvironment,
}
pconfig2.Args = []string{"sh", "-c", "cat && readlink /proc/self/ns/pid"}
pconfig2.Stdin = stdinR2
pconfig2.Stdout = &stdout2
err = container.Start(&pconfig2)
stdinR2.Close()
defer stdinW2.Close()
ok(t, err)
pid2, err := pconfig2.Pid()
ok(t, err)
processes, err := container.Processes()
ok(t, err)
n := 0
for i := range processes {
if processes[i] == pid || processes[i] == pid2 {
n++
}
}
if n != 2 {
t.Fatal("unexpected number of processes", processes, pid, pid2)
}
// Wait processes
stdinW2.Close()
waitProcess(&pconfig2, t)
stdinW.Close()
waitProcess(&pconfig, t)
// Check that both processes live in the same pidns
pidns := string(stdout.Bytes())
ok(t, err)
pidns2 := string(stdout2.Bytes())
ok(t, err)
if pidns != pidns2 {
t.Fatal("The second process isn't in the required pid namespace", pidns, pidns2)
}
}
func TestCheckpoint(t *testing.T) {
if testing.Short() {
return
}
root, err := newTestRoot()
if err != nil {
t.Fatal(err)
}
defer os.RemoveAll(root)
rootfs, err := newRootfs()
if err != nil {
t.Fatal(err)
}
defer remove(rootfs)
config := newTemplateConfig(rootfs)
config.Mounts = append(config.Mounts, &configs.Mount{
Destination: "/sys/fs/cgroup",
Device: "cgroup",
Flags: defaultMountFlags | syscall.MS_RDONLY,
})
factory, err := libcontainer.New(root, libcontainer.Cgroupfs)
if err != nil {
t.Fatal(err)
}
container, err := factory.Create("test", config)
if err != nil {
t.Fatal(err)
}
defer container.Destroy()
stdinR, stdinW, err := os.Pipe()
if err != nil {
t.Fatal(err)
}
var stdout bytes.Buffer
pconfig := libcontainer.Process{
Cwd: "/",
Args: []string{"cat"},
Env: standardEnvironment,
Stdin: stdinR,
Stdout: &stdout,
}
err = container.Start(&pconfig)
stdinR.Close()
defer stdinW.Close()
if err != nil {
t.Fatal(err)
}
pid, err := pconfig.Pid()
if err != nil {
t.Fatal(err)
}
process, err := os.FindProcess(pid)
if err != nil {
t.Fatal(err)
}
imagesDir, err := ioutil.TempDir("", "criu")
if err != nil {
t.Fatal(err)
}
defer os.RemoveAll(imagesDir)
checkpointOpts := &libcontainer.CriuOpts{
ImagesDirectory: imagesDir,
WorkDirectory: imagesDir,
}
dumpLog := filepath.Join(checkpointOpts.WorkDirectory, "dump.log")
restoreLog := filepath.Join(checkpointOpts.WorkDirectory, "restore.log")
if err := container.Checkpoint(checkpointOpts); err != nil {
showFile(t, dumpLog)
t.Fatal(err)
}
state, err := container.Status()
if err != nil {
t.Fatal(err)
}
if state != libcontainer.Running {
t.Fatal("Unexpected state checkpoint: ", state)
}
stdinW.Close()
_, err = process.Wait()
if err != nil {
t.Fatal(err)
}
// reload the container
container, err = factory.Load("test")
if err != nil {
t.Fatal(err)
}
restoreStdinR, restoreStdinW, err := os.Pipe()
if err != nil {
t.Fatal(err)
}
restoreProcessConfig := &libcontainer.Process{
Cwd: "/",
Stdin: restoreStdinR,
Stdout: &stdout,
}
err = container.Restore(restoreProcessConfig, checkpointOpts)
restoreStdinR.Close()
defer restoreStdinW.Close()
if err != nil {
showFile(t, restoreLog)
t.Fatal(err)
}
state, err = container.Status()
if err != nil {
t.Fatal(err)
}
if state != libcontainer.Running {
t.Fatal("Unexpected restore state: ", state)
}
pid, err = restoreProcessConfig.Pid()
if err != nil {
t.Fatal(err)
}
process, err = os.FindProcess(pid)
if err != nil {
t.Fatal(err)
}
_, err = restoreStdinW.WriteString("Hello!")
if err != nil {
t.Fatal(err)
}
restoreStdinW.Close()
s, err := process.Wait()
if err != nil {
t.Fatal(err)
}
if !s.Success() {
t.Fatal(s.String(), pid)
}
output := string(stdout.Bytes())
if !strings.Contains(output, "Hello!") {
t.Fatal("Did not restore the pipe correctly:", output)
}
}
func TestCheckpoint(t *testing.T) {
if testing.Short() {
return
}
root, err := newTestRoot()
if err != nil {
t.Fatal(err)
}
defer os.RemoveAll(root)
rootfs, err := newRootfs()
if err != nil {
t.Fatal(err)
}
defer remove(rootfs)
config := newTemplateConfig(rootfs)
factory, err := libcontainer.New(root, libcontainer.Cgroupfs)
if err != nil {
t.Fatal(err)
}
container, err := factory.Create("test", config)
if err != nil {
t.Fatal(err)
}
defer container.Destroy()
stdinR, stdinW, err := os.Pipe()
if err != nil {
t.Fatal(err)
}
var stdout bytes.Buffer
pconfig := libcontainer.Process{
Args: []string{"cat"},
Env: standardEnvironment,
Stdin: stdinR,
Stdout: &stdout,
}
err = container.Start(&pconfig)
stdinR.Close()
defer stdinW.Close()
if err != nil {
t.Fatal(err)
}
pid, err := pconfig.Pid()
if err != nil {
t.Fatal(err)
}
process, err := os.FindProcess(pid)
if err != nil {
t.Fatal(err)
}
imagesDir, err := ioutil.TempDir("", "criu")
if err != nil {
t.Fatal(err)
}
defer os.RemoveAll(imagesDir)
checkpointOpts := &libcontainer.CriuOpts{
ImagesDirectory: imagesDir,
WorkDirectory: imagesDir,
}
if err := container.Checkpoint(checkpointOpts); err != nil {
t.Fatal(err)
}
state, err := container.Status()
if err != nil {
t.Fatal(err)
}
if state != libcontainer.Checkpointed {
t.Fatal("Unexpected state: ", state)
}
stdinW.Close()
_, err = process.Wait()
if err != nil {
t.Fatal(err)
}
// reload the container
container, err = factory.Load("test")
if err != nil {
t.Fatal(err)
}
restoreStdinR, restoreStdinW, err := os.Pipe()
if err != nil {
t.Fatal(err)
}
restoreProcessConfig := &libcontainer.Process{
Stdin: restoreStdinR,
Stdout: &stdout,
}
err = container.Restore(restoreProcessConfig, &libcontainer.CriuOpts{
ImagesDirectory: imagesDir,
})
restoreStdinR.Close()
defer restoreStdinW.Close()
state, err = container.Status()
if err != nil {
t.Fatal(err)
}
if state != libcontainer.Running {
t.Fatal("Unexpected state: ", state)
}
pid, err = restoreProcessConfig.Pid()
if err != nil {
t.Fatal(err)
}
process, err = os.FindProcess(pid)
if err != nil {
t.Fatal(err)
}
_, err = restoreStdinW.WriteString("Hello!")
if err != nil {
t.Fatal(err)
}
restoreStdinW.Close()
s, err := process.Wait()
if err != nil {
t.Fatal(err)
}
if !s.Success() {
t.Fatal(s.String(), pid)
}
output := string(stdout.Bytes())
if !strings.Contains(output, "Hello!") {
t.Fatal("Did not restore the pipe correctly:", output)
}
}
