Initial windows runtime work

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

cmd/ctr/exec_windows.go

@@ -0,0 +1,40 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"time"
+
+	"github.com/containerd/containerd/api/services/execution"
+	protobuf "github.com/gogo/protobuf/types"
+	specs "github.com/opencontainers/runtime-spec/specs-go"
+	"github.com/urfave/cli"
+)
+
+func newExecRequest(context *cli.Context, tmpDir, id string) (*execution.ExecRequest, error) {
+	process := specs.Process{
+		Args:     context.Args(),
+		Terminal: context.Bool("tty"),
+		Cwd:      context.String("cwd"),
+	}
+	data, err := json.Marshal(process)
+	if err != nil {
+		return nil, err
+	}
+	now := time.Now().UnixNano()
+	request := &execution.ExecRequest{
+		ID: id,
+		Spec: &protobuf.Any{
+			TypeUrl: specs.Version,
+			Value:   data,
+		},
+		Terminal: context.Bool("tty"),
+		Stdin:    fmt.Sprintf(`%s\ctr-%s-stdin-`, pipeRoot, id, now),
+		Stdout:   fmt.Sprintf(`%s\ctr-%s-stdout-`, pipeRoot, id, now),
+	}
+	if !request.Terminal {
+		request.Stderr = fmt.Sprintf(`%s\ctr-%s-stderr-`, pipeRoot, id, now)
+	}
+
+	return request, nil
+}