Remove ulele/deepcopier in favor of JSON deep copy

We have a very high performance JSON library that doesn't need to
perform code generation. Let's use it instead of our questionably
performant, reflection-dependent deep copy library.

Most changes because some functions can now return errors.

Also converts cmd/podman to use jsoniter, instead of pkg/json,
for increased performance.

Signed-off-by: Matthew Heon <matthew.heon@pm.me>

6 files changed, 39 insertions, 15 deletions

diff --git a/libpod/container.go b/libpod/container.go
index 806e75c63..6d80a9bf4 100644
--- a/libpod/container.go
+++ b/libpod/container.go
@@ -17,7 +17,6 @@ import (
 	"github.com/cri-o/ocicni/pkg/ocicni"
 	spec "github.com/opencontainers/runtime-spec/specs-go"
 	"github.com/pkg/errors"
-	"github.com/ulule/deepcopier"
 )
 
 // ContainerStatus represents the current state of a container
@@ -407,7 +406,9 @@ func (t ContainerStatus) String() string {
 // Config returns the configuration used to create the container
 func (c *Container) Config() *ContainerConfig {
 	returnConfig := new(ContainerConfig)
-	deepcopier.Copy(c.config).To(returnConfig)
+	if err := JSONDeepCopy(c.config, returnConfig); err != nil {
+		return nil
+	}
 
 	return returnConfig
 }
@@ -417,7 +418,9 @@ func (c *Container) Config() *ContainerConfig {
 // spec may differ slightly as mounts are added based on the image
 func (c *Container) Spec() *spec.Spec {
 	returnSpec := new(spec.Spec)
-	deepcopier.Copy(c.config.Spec).To(returnSpec)
+	if err := JSONDeepCopy(c.config.Spec, returnSpec); err != nil {
+		return nil
+	}
 
 	return returnSpec
 }
@@ -1094,7 +1097,9 @@ func (c *Container) ContainerState() (*ContainerState, error) {
 		}
 	}
 	returnConfig := new(ContainerState)
-	deepcopier.Copy(c.state).To(returnConfig)
+	if err := JSONDeepCopy(c.state, returnConfig); err != nil {
+		return nil, errors.Wrapf(err, "error copying container %s state", c.ID())
+	}
 	return c.state, nil
 }
 
diff --git a/libpod/events.go b/libpod/events.go
index 139600982..b6a277789 100644
--- a/libpod/events.go
+++ b/libpod/events.go
@@ -58,6 +58,10 @@ func (v *Volume) newVolumeEvent(status events.Status) {
 // Events is a wrapper function for everyone to begin tailing the events log
 // with options
 func (r *Runtime) Events(fromStart, stream bool, options []events.EventFilter, eventChannel chan *events.Event) error {
+	if !r.valid {
+		return ErrRuntimeStopped
+	}
+
 	t, err := r.getTail(fromStart, stream)
 	if err != nil {
 		return err
@@ -71,7 +75,7 @@ func (r *Runtime) Events(fromStart, stream bool, options []events.EventFilter, e
 		case events.Image, events.Volume, events.Pod, events.Container:
 		//	no-op
 		default:
-			return errors.Errorf("event type %s is not valid in %s", event.Type.String(), r.GetConfig().EventsLogFilePath)
+			return errors.Errorf("event type %s is not valid in %s", event.Type.String(), r.config.EventsLogFilePath)
 		}
 		include := true
 		for _, filter := range options {
diff --git a/libpod/pod_api.go b/libpod/pod_api.go
index b9a11000e..9a6baf23e 100644
--- a/libpod/pod_api.go
+++ b/libpod/pod_api.go
@@ -6,7 +6,6 @@ import (
 	"github.com/containers/libpod/libpod/events"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
-	"github.com/ulule/deepcopier"
 )
 
 // Start starts all containers within a pod
@@ -441,7 +440,9 @@ func (p *Pod) Inspect() (*PodInspect, error) {
 	infraContainerID := p.state.InfraContainerID
 
 	config := new(PodConfig)
-	deepcopier.Copy(p.config).To(config)
+	if err := JSONDeepCopy(p.config, config); err != nil {
+		return nil, err
+	}
 	inspectData := PodInspect{
 		Config: config,
 		State: &PodInspectState{
diff --git a/libpod/runtime.go b/libpod/runtime.go
index b3b75d791..a4fc9e493 100644
--- a/libpod/runtime.go
+++ b/libpod/runtime.go
@@ -23,7 +23,6 @@ import (
 	"github.com/docker/docker/pkg/namesgenerator"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
-	"github.com/ulule/deepcopier"
 )
 
 // RuntimeStateStore is a constant indicating which state store implementation
@@ -355,7 +354,9 @@ func newRuntimeFromConfig(userConfigPath string, options ...RuntimeOption) (runt
 	if err != nil {
 		return nil, err
 	}
-	deepcopier.Copy(defaultRuntimeConfig).To(runtime.config)
+	if err := JSONDeepCopy(defaultRuntimeConfig, runtime.config); err != nil {
+		return nil, errors.Wrapf(err, "error copying runtime default config")
+	}
 	runtime.config.TmpDir = tmpDir
 
 	storageConf, err := util.GetDefaultStoreOptions()
@@ -923,20 +924,22 @@ func makeRuntime(runtime *Runtime) (err error) {
 }
 
 // GetConfig returns a copy of the configuration used by the runtime
-func (r *Runtime) GetConfig() *RuntimeConfig {
+func (r *Runtime) GetConfig() (*RuntimeConfig, error) {
 	r.lock.RLock()
 	defer r.lock.RUnlock()
 
 	if !r.valid {
-		return nil
+		return nil, ErrRuntimeStopped
 	}
 
 	config := new(RuntimeConfig)
 
 	// Copy so the caller won't be able to modify the actual config
-	deepcopier.Copy(r.config).To(config)
+	if err := JSONDeepCopy(r.config, config); err != nil {
+		return nil, errors.Wrapf(err, "error copying config")
+	}
 
-	return config
+	return config, nil
 }
 
 // Shutdown shuts down the runtime and associated containers and storage
diff --git a/libpod/runtime_ctr.go b/libpod/runtime_ctr.go
index f23dc86dd..7c39d8ced 100644
--- a/libpod/runtime_ctr.go
+++ b/libpod/runtime_ctr.go
@@ -19,7 +19,6 @@ import (
 	opentracing "github.com/opentracing/opentracing-go"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
-	"github.com/ulule/deepcopier"
 )
 
 // CtrRemoveTimeout is the default number of seconds to wait after stopping a container
@@ -63,7 +62,9 @@ func (r *Runtime) newContainer(ctx context.Context, rSpec *spec.Spec, options ..
 	ctr.config.ID = stringid.GenerateNonCryptoID()
 
 	ctr.config.Spec = new(spec.Spec)
-	deepcopier.Copy(rSpec).To(ctr.config.Spec)
+	if err := JSONDeepCopy(rSpec, ctr.config.Spec); err != nil {
+		return nil, errors.Wrapf(err, "error copying runtime spec while creating container")
+	}
 	ctr.config.CreatedTime = time.Now()
 
 	ctr.config.ShmSize = DefaultShmSize
diff --git a/libpod/util.go b/libpod/util.go
index b7578135a..7e2dff21a 100644
--- a/libpod/util.go
+++ b/libpod/util.go
@@ -187,3 +187,13 @@ func validPodNSOption(p *Pod, ctrPod string) error {
 	}
 	return nil
 }
+
+// JSONDeepCopy performs a deep copy by performing a JSON encode/decode of the
+// given structures. From and To should be identically typed structs.
+func JSONDeepCopy(from, to interface{}) error {
+	tmp, err := json.Marshal(from)
+	if err != nil {
+		return err
+	}
+	return json.Unmarshal(tmp, to)
+}