Initial windows runtime work

Signed-off-by: Kenfe-Mickael Laventure <mickael.laventure@gmail.com>

snapshot/windows/windows.go

@@ -0,0 +1,76 @@
+// +build windows
+
+package windows
+
+import (
+	"context"
+	"path/filepath"
+
+	"github.com/containerd/containerd"
+	"github.com/containerd/containerd/plugin"
+	"github.com/containerd/containerd/snapshot"
+	"github.com/pkg/errors"
+)
+
+var (
+	ErrNotImplemented = errors.New("not implemented")
+)
+
+func init() {
+	plugin.Register("snapshot-windows", &plugin.Registration{
+		Type: plugin.SnapshotPlugin,
+		Init: func(ic *plugin.InitContext) (interface{}, error) {
+			return NewSnapshotter(filepath.Join(ic.Root, "snapshot", "windows"))
+		},
+	})
+}
+
+type Snapshotter struct {
+	root string
+}
+
+func NewSnapshotter(root string) (snapshot.Snapshotter, error) {
+	return &Snapshotter{
+		root: root,
+	}, nil
+}
+
+// Stat returns the info for an active or committed snapshot by name or
+// key.
+//
+// Should be used for parent resolution, existence checks and to discern
+// the kind of snapshot.
+func (o *Snapshotter) Stat(ctx context.Context, key string) (snapshot.Info, error) {
+	panic("not implemented")
+}
+
+func (o *Snapshotter) Prepare(ctx context.Context, key, parent string) ([]containerd.Mount, error) {
+	panic("not implemented")
+}
+
+func (o *Snapshotter) View(ctx context.Context, key, parent string) ([]containerd.Mount, error) {
+	panic("not implemented")
+}
+
+// Mounts returns the mounts for the transaction identified by key. Can be
+// called on an read-write or readonly transaction.
+//
+// This can be used to recover mounts after calling View or Prepare.
+func (o *Snapshotter) Mounts(ctx context.Context, key string) ([]containerd.Mount, error) {
+	panic("not implemented")
+}
+
+func (o *Snapshotter) Commit(ctx context.Context, name, key string) error {
+	panic("not implemented")
+}
+
+// Remove abandons the transaction identified by key. All resources
+// associated with the key will be removed.
+func (o *Snapshotter) Remove(ctx context.Context, key string) error {
+	panic("not implemented")
+}
+
+// Walk the committed snapshots.
+func (o *Snapshotter) Walk(ctx context.Context, fn func(context.Context, snapshot.Info) error) error {
+	panic("not implemented")
+}