Move runtime to core/runtime

Signed-off-by: Derek McGowan <derek@mcg.dev>

core/runtime/v2/logging/logging.go

@@ -0,0 +1,37 @@
+/*
+   Copyright The containerd Authors.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package logging
+
+import (
+	"context"
+	"io"
+)
+
+// Config of the container logs
+type Config struct {
+	ID        string
+	Namespace string
+	Stdout    io.Reader
+	Stderr    io.Reader
+}
+
+// LoggerFunc is implemented by custom v2 logging binaries.
+//
+// ready should be called when the logging binary finishes its setup and the container can be started.
+//
+// An example implementation of LoggerFunc: https://github.com/containerd/containerd/tree/main/runtime/v2#logging
+type LoggerFunc func(ctx context.Context, cfg *Config, ready func() error) error