Import CRI remote client package.

Signed-off-by: Lantao Liu <lantaol@google.com>

vendor/k8s.io/kubernetes/pkg/kubelet/util/util_unix.go

@@ -0,0 +1,79 @@
+// +build freebsd linux
+
+/*
+Copyright 2017 The Kubernetes 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 util
+
+import (
+	"fmt"
+	"net"
+	"os"
+	"time"
+
+	"github.com/golang/glog"
+	"golang.org/x/sys/unix"
+)
+
+const (
+	// unixProtocol is the network protocol of unix socket.
+	unixProtocol = "unix"
+)
+
+func CreateListener(endpoint string) (net.Listener, error) {
+	protocol, addr, err := parseEndpointWithFallbackProtocol(endpoint, unixProtocol)
+	if err != nil {
+		return nil, err
+	}
+	if protocol != unixProtocol {
+		return nil, fmt.Errorf("only support unix socket endpoint")
+	}
+
+	// Unlink to cleanup the previous socket file.
+	err = unix.Unlink(addr)
+	if err != nil && !os.IsNotExist(err) {
+		return nil, fmt.Errorf("failed to unlink socket file %q: %v", addr, err)
+	}
+
+	return net.Listen(protocol, addr)
+}
+
+func GetAddressAndDialer(endpoint string) (string, func(addr string, timeout time.Duration) (net.Conn, error), error) {
+	protocol, addr, err := parseEndpointWithFallbackProtocol(endpoint, unixProtocol)
+	if err != nil {
+		return "", nil, err
+	}
+	if protocol != unixProtocol {
+		return "", nil, fmt.Errorf("only support unix socket endpoint")
+	}
+
+	return addr, dial, nil
+}
+
+func dial(addr string, timeout time.Duration) (net.Conn, error) {
+	return net.DialTimeout(unixProtocol, addr, timeout)
+}
+
+func parseEndpointWithFallbackProtocol(endpoint string, fallbackProtocol string) (protocol string, addr string, err error) {
+	if protocol, addr, err = parseEndpoint(endpoint); err != nil && protocol == "" {
+		fallbackEndpoint := fallbackProtocol + "://" + endpoint
+		protocol, addr, err = parseEndpoint(fallbackEndpoint)
+		if err == nil {
+			glog.Warningf("Using %q as endpoint is deprecated, please consider using full url format %q.", endpoint, fallbackEndpoint)
+		}
+	}
+	return
+}