package daemon // import "github.com/docker/docker/daemon" import ( "context" "fmt" "os" "path/filepath" "github.com/docker/docker/api/types" "github.com/docker/docker/daemon/names" ) var ( validCheckpointNameChars = names.RestrictedNameChars validCheckpointNamePattern = names.RestrictedNamePattern ) // getCheckpointDir verifies checkpoint directory for create,remove, list options and checks if checkpoint already exists func getCheckpointDir(checkDir, checkpointID, ctrName, ctrID, ctrCheckpointDir string, create bool) (string, error) { var checkpointDir string var err2 error if checkDir != "" { checkpointDir = checkDir } else { checkpointDir = ctrCheckpointDir } checkpointAbsDir := filepath.Join(checkpointDir, checkpointID) stat, err := os.Stat(checkpointAbsDir) if create { switch { case err == nil && stat.IsDir(): err2 = fmt.Errorf("checkpoint with name %s already exists for container %s", checkpointID, ctrName) case err != nil && os.IsNotExist(err): err2 = os.MkdirAll(checkpointAbsDir, 0700) case err != nil: err2 = err default: err2 = fmt.Errorf("%s exists and is not a directory", checkpointAbsDir) } } else { switch { case err != nil: err2 = fmt.Errorf("checkpoint %s does not exist for container %s", checkpointID, ctrName) case stat.IsDir(): err2 = nil default: err2 = fmt.Errorf("%s exists and is not a directory", checkpointAbsDir) } } return checkpointAbsDir, err2 } // CheckpointCreate checkpoints the process running in a container with CRIU func (daemon *Daemon) CheckpointCreate(name string, config types.CheckpointCreateOptions) error { container, err := daemon.GetContainer(name) if err != nil { return err } if !container.IsRunning() { return fmt.Errorf("Container %s not running", name) } if !validCheckpointNamePattern.MatchString(config.CheckpointID) { return fmt.Errorf("Invalid checkpoint ID (%s), only %s are allowed", config.CheckpointID, validCheckpointNameChars) } checkpointDir, err := getCheckpointDir(config.CheckpointDir, config.CheckpointID, name, container.ID, container.CheckpointDir(), true) if err != nil { return fmt.Errorf("cannot checkpoint container %s: %s", name, err) } err = daemon.containerd.CreateCheckpoint(context.Background(), container.ID, checkpointDir, config.Exit) if err != nil { os.RemoveAll(checkpointDir) return fmt.Errorf("Cannot checkpoint container %s: %s", name, err) } daemon.LogContainerEvent(container, "checkpoint") return nil } // CheckpointDelete deletes the specified checkpoint func (daemon *Daemon) CheckpointDelete(name string, config types.CheckpointDeleteOptions) error { container, err := daemon.GetContainer(name) if err != nil { return err } checkpointDir, err := getCheckpointDir(config.CheckpointDir, config.CheckpointID, name, container.ID, container.CheckpointDir(), false) if err == nil { return os.RemoveAll(checkpointDir) } return err } // CheckpointList lists all checkpoints of the specified container func (daemon *Daemon) CheckpointList(name string, config types.CheckpointListOptions) ([]types.Checkpoint, error) { var out []types.Checkpoint container, err := daemon.GetContainer(name) if err != nil { return nil, err } checkpointDir, err := getCheckpointDir(config.CheckpointDir, "", name, container.ID, container.CheckpointDir(), false) if err != nil { return nil, err } if err := os.MkdirAll(checkpointDir, 0755); err != nil { return nil, err } dirs, err := os.ReadDir(checkpointDir) if err != nil { return nil, err } for _, d := range dirs { if !d.IsDir() { continue } cpt := types.Checkpoint{Name: d.Name()} out = append(out, cpt) } return out, nil }