2 files changed, 47 insertions, 0 deletions
diff --git a/libpod/define/containerstate.go b/libpod/define/containerstate.go
index e7d258e21..6da49a594 100644
--- a/libpod/define/containerstate.go
+++ b/libpod/define/containerstate.go
@@ -78,3 +78,37 @@ func StringToContainerStatus(status string) (ContainerStatus, error) {
 		return ContainerStateUnknown, errors.Wrapf(ErrInvalidArg, "unknown container state: %s", status)
 	}
 }
+
+// ContainerExecStatus is the status of an exec session within a container.
+type ContainerExecStatus int
+
+const (
+	// ExecStateUnknown indicates that the state of the exec session is not
+	// known.
+	ExecStateUnknown ContainerExecStatus = iota
+	// ExecStateCreated indicates that the exec session has been created but
+	// not yet started
+	ExecStateCreated ContainerExecStatus = iota
+	// ExecStateRunning indicates that the exec session has been started but
+	// has not yet exited.
+	ExecStateRunning ContainerExecStatus = iota
+	// ExecStateStopped indicates that the exec session has stopped and is
+	// no longer running.
+	ExecStateStopped ContainerExecStatus = iota
+)
+
+// String returns a string representation of a given exec state.
+func (s ContainerExecStatus) String() string {
+	switch s {
+	case ExecStateUnknown:
+		return "unknown"
+	case ExecStateCreated:
+		return "created"
+	case ExecStateRunning:
+		return "running"
+	case ExecStateStopped:
+		return "stopped"
+	default:
+		return "bad state"
+	}
+}
diff --git a/libpod/define/errors.go b/libpod/define/errors.go
index b79cf08dc..3ba343789 100644
--- a/libpod/define/errors.go
+++ b/libpod/define/errors.go
@@ -20,6 +20,10 @@ var (
 	// ErrNoSuchVolume indicates the requested volume does not exist
 	ErrNoSuchVolume = errors.New("no such volume")
 
+	// ErrNoSuchExecSession indicates that the requested exec session does
+	// not exist.
+	ErrNoSuchExecSession = errors.New("no such exec session")
+
 	// ErrCtrExists indicates a container with the same name or ID already
 	// exists
 	ErrCtrExists = errors.New("container already exists")
@@ -29,10 +33,16 @@ var (
 	ErrImageExists = errors.New("image already exists")
 	// ErrVolumeExists indicates a volume with the same name already exists
 	ErrVolumeExists = errors.New("volume already exists")
+	// ErrExecSessionExists indicates an exec session with the same ID
+	// already exists.
+	ErrExecSessionExists = errors.New("exec session already exists")
 
 	// ErrCtrStateInvalid indicates a container is in an improper state for
 	// the requested operation
 	ErrCtrStateInvalid = errors.New("container state improper")
+	// ErrExecSessionStateInvalid indicates that an exec session is in an
+	// improper state for the requested operation
+	ErrExecSessionStateInvalid = errors.New("exec session state improper")
 	// ErrVolumeBeingUsed indicates that a volume is being used by at least one container
 	ErrVolumeBeingUsed = errors.New("volume is being used")
 
@@ -90,6 +100,9 @@ var (
 	// ErrVolumeRemoved indicates that the volume has already been removed and
 	// no further operations can be performed on it
 	ErrVolumeRemoved = errors.New("volume has already been removed")
+	// ErrExecSessionRemoved indicates that the exec session has already
+	// been removed and no further operations can be performed on it.
+	ErrExecSessionRemoved = errors.New("exec session has already been removed")
 
 	// ErrDBClosed indicates that the connection to the state database has
 	// already been closed