Fix manual detach from containers to not wait for exit

At present, when manually detaching from an attached container
(using the detach hotkeys, default C-p C-q), Podman will still
wait for the container to exit to obtain its exit code (so we can
set Podman's exit code to match). This is correct in the case
where attach finished because the container exited, but very
wrong for the manual detach case.

As a result of this, we can no longer guarantee that the cleanup
and --rm functions will fire at the end of 'podman run' - we may
be exiting before we get that far. Cleanup is easy enough - we
swap to unconditionally using the cleanup processes we've used
for detached and rootless containers all along. To duplicate --rm
we need to also teach 'podman cleanup' to optionally remove
containers instead of cleaning them up.

(There is an argument for just using 'podman rm' instead of
'podman cleanup --rm', but cleanup does have different semantics
given that we only ever expect it to run when the container has
just exited. I think it might be useful to keep the two separate
for things like 'podman events'...)

Signed-off-by: Matthew Heon <mheon@redhat.com>

cmd/podman/attach.go

@@ -74,7 +74,7 @@ func attachCmd(c *cliconfig.AttachValues) error {
 		inputStream = nil
 	}
 
-	if err := startAttachCtr(ctr, os.Stdout, os.Stderr, inputStream, c.DetachKeys, c.SigProxy, false); err != nil {
+	if err := startAttachCtr(ctr, os.Stdout, os.Stderr, inputStream, c.DetachKeys, c.SigProxy, false); err != nil && err != libpod.ErrDetach {
 		return errors.Wrapf(err, "error attaching to container %s", ctr.ID())
 	}
 

cmd/podman/cleanup.go

@@ -37,6 +37,7 @@ func init() {
 
 	flags.BoolVarP(&cleanupCommand.All, "all", "a", false, "Cleans up all containers")
 	flags.BoolVarP(&cleanupCommand.Latest, "latest", "l", false, "Act on the latest container podman is aware of")
+	flags.BoolVar(&cleanupCommand.Rm, "rm", false, "After cleanup, remove the container entirely")
 }
 
 func cleanupCmd(c *cliconfig.CleanupValues) error {
@@ -55,12 +56,25 @@ func cleanupCmd(c *cliconfig.CleanupValues) error {
 	ctx := getContext()
 
 	for _, ctr := range cleanupContainers {
-		if err = ctr.Cleanup(ctx); err != nil {
-			if lastError != nil {
-				fmt.Fprintln(os.Stderr, lastError)
+		hadError := false
+		if c.Rm {
+			if err := runtime.RemoveContainer(ctx, ctr, false); err != nil {
+				if lastError != nil {
+					fmt.Fprintln(os.Stderr, lastError)
+				}
+				lastError = errors.Wrapf(err, "failed to cleanup and remove container %v", ctr.ID())
+				hadError = true
 			}
-			lastError = errors.Wrapf(err, "failed to cleanup container %v", ctr.ID())
 		} else {
+			if err := ctr.Cleanup(ctx); err != nil {
+				if lastError != nil {
+					fmt.Fprintln(os.Stderr, lastError)
+				}
+				lastError = errors.Wrapf(err, "failed to cleanup container %v", ctr.ID())
+				hadError = true
+			}
+		}
+		if !hadError {
 			fmt.Println(ctr.ID())
 		}
 	}

cmd/podman/cliconfig/config.go

@@ -531,6 +531,7 @@ type CleanupValues struct {
 	PodmanCommand
 	All    bool
 	Latest bool
+	Rm     bool
 }
 
 type SystemPruneValues struct {

cmd/podman/run.go

@@ -118,6 +118,14 @@ func runCmd(c *cliconfig.RunValues) error {
 		}
 	}
 	if err := startAttachCtr(ctr, outputStream, errorStream, inputStream, c.String("detach-keys"), c.Bool("sig-proxy"), true); err != nil {
+		// We've manually detached from the container
+		// Do not perform cleanup, or wait for container exit code
+		// Just exit immediately
+		if err == libpod.ErrDetach {
+			exitCode = 0
+			return nil
+		}
+
 		// This means the command did not exist
 		exitCode = 127
 		if strings.Index(err.Error(), "permission denied") > -1 {
@@ -147,22 +155,6 @@ func runCmd(c *cliconfig.RunValues) error {
 		exitCode = int(ecode)
 	}
 
-	if createConfig.Rm {
-		return runtime.RemoveContainer(ctx, ctr, true)
-	}
-
-	if err := ctr.Cleanup(ctx); err != nil {
-		// If the container has been removed already, no need to error on cleanup
-		// Also, if it was restarted, don't error either
-		if errors.Cause(err) == libpod.ErrNoSuchCtr ||
-			errors.Cause(err) == libpod.ErrCtrRemoved ||
-			errors.Cause(err) == libpod.ErrCtrStateInvalid {
-			return nil
-		}
-
-		return err
-	}
-
 	return nil
 }
 

cmd/podman/start.go

@@ -108,6 +108,13 @@ func startCmd(c *cliconfig.StartValues) error {
 
 			// attach to the container and also start it not already running
 			err = startAttachCtr(ctr, os.Stdout, os.Stderr, inputStream, c.DetachKeys, sigProxy, !ctrRunning)
+			if err == libpod.ErrDetach {
+				// User manually detached
+				// Exit cleanly immediately
+				exitCode = 0
+				return nil
+			}
+
 			if ctrRunning {
 				return err
 			}

cmd/podman/utils.go

@@ -91,7 +91,7 @@ func startAttachCtr(ctr *libpod.Container, stdout, stderr, stdin *os.File, detac
 
 	err = <-attachChan
 	if err != nil {
-		return errors.Wrapf(err, "error attaching to container %s", ctr.ID())
+		return err
 	}
 
 	return nil

libpod/container_attach_linux.go

@@ -109,8 +109,8 @@ func (c *Container) attachContainerSocket(resize <-chan remotecommand.TerminalSi
 	case err := <-receiveStdoutError:
 		return err
 	case err := <-stdinDone:
-		if _, ok := err.(utils.DetachError); ok {
-			return nil
+		if err == ErrDetach {
+			return err
 		}
 		if streams.AttachOutput || streams.AttachError {
 			return <-receiveStdoutError

libpod/errors.go

@@ -4,6 +4,7 @@ import (
 	"errors"
 
 	"github.com/containers/libpod/libpod/image"
+	"github.com/containers/libpod/utils"
 )
 
 var (
@@ -56,6 +57,10 @@ var (
 	// ErrInternal indicates an internal library error
 	ErrInternal = errors.New("internal libpod error")
 
+	// ErrDetach indicates that an attach session was manually detached by
+	// the user.
+	ErrDetach = utils.ErrDetach
+
 	// ErrRuntimeStopped indicates that the runtime has already been shut
 	// down and no further operations can be performed on it
 	ErrRuntimeStopped = errors.New("runtime has already been stopped")

pkg/spec/createconfig.go

@@ -11,7 +11,6 @@ import (
 
 	"github.com/containers/libpod/libpod"
 	"github.com/containers/libpod/pkg/namespaces"
-	"github.com/containers/libpod/pkg/rootless"
 	"github.com/containers/storage"
 	"github.com/cri-o/ocicni/pkg/ocicni"
 	"github.com/docker/go-connections/nat"
@@ -340,7 +339,13 @@ func (c *CreateConfig) createExitCommand() []string {
 	if c.Syslog {
 		command = append(command, "--syslog")
 	}
-	return append(command, []string{"container", "cleanup"}...)
+	command = append(command, []string{"container", "cleanup"}...)
+
+	if c.Rm {
+		command = append(command, "--rm")
+	}
+
+	return command
 }
 
 // GetContainerCreateOptions takes a CreateConfig and returns a slice of CtrCreateOptions
@@ -518,11 +523,9 @@ func (c *CreateConfig) GetContainerCreateOptions(runtime *libpod.Runtime, pod *l
 	if c.CgroupParent != "" {
 		options = append(options, libpod.WithCgroupParent(c.CgroupParent))
 	}
-	// For a rootless container always cleanup the storage/network as they
-	// run in a different namespace thus not reusable when we restart.
-	if c.Detach || rootless.IsRootless() {
-		options = append(options, libpod.WithExitCommand(c.createExitCommand()))
-	}
+
+	// Always use a cleanup process to clean up Podman after termination
+	options = append(options, libpod.WithExitCommand(c.createExitCommand()))
 
 	return options, nil
 }

utils/utils.go

@@ -9,6 +9,7 @@ import (
 
 	systemdDbus "github.com/coreos/go-systemd/dbus"
 	"github.com/godbus/dbus"
+	"github.com/pkg/errors"
 )
 
 // ExecCmd executes a command with args and returns its output as a string along
@@ -82,12 +83,9 @@ func newProp(name string, units interface{}) systemdDbus.Property {
 	}
 }
 
-// DetachError is special error which returned in case of container detach.
-type DetachError struct{}
-
-func (DetachError) Error() string {
-	return "detached from container"
-}
+// ErrDetach is an error indicating that the user manually detached from the
+// container.
+var ErrDetach = errors.New("detached from container")
 
 // CopyDetachable is similar to io.Copy but support a detach key sequence to break out.
 func CopyDetachable(dst io.Writer, src io.Reader, keys []byte) (written int64, err error) {
@@ -108,7 +106,7 @@ func CopyDetachable(dst io.Writer, src io.Reader, keys []byte) (written int64, e
 				}
 				if i == len(keys)-1 {
 					// src.Close()
-					return 0, DetachError{}
+					return 0, ErrDetach
 				}
 				nr, er = src.Read(buf)
 			}