Import of https://github.com/ciena/voltctl at commit 40d61fbf3f910ed4017cf67c9c79e8e1f82a33a5

Change-Id: I8464c59e60d76cb8612891db3303878975b5416c
diff --git a/vendor/k8s.io/apimachinery/pkg/apis/meta/v1/labels.go b/vendor/k8s.io/apimachinery/pkg/apis/meta/v1/labels.go
new file mode 100644
index 0000000..9b45145
--- /dev/null
+++ b/vendor/k8s.io/apimachinery/pkg/apis/meta/v1/labels.go
@@ -0,0 +1,55 @@
+/*
+Copyright 2016 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 v1
+
+// Clones the given selector and returns a new selector with the given key and value added.
+// Returns the given selector, if labelKey is empty.
+func CloneSelectorAndAddLabel(selector *LabelSelector, labelKey, labelValue string) *LabelSelector {
+	if labelKey == "" {
+		// Don't need to add a label.
+		return selector
+	}
+
+	// Clone.
+	newSelector := selector.DeepCopy()
+
+	if newSelector.MatchLabels == nil {
+		newSelector.MatchLabels = make(map[string]string)
+	}
+
+	newSelector.MatchLabels[labelKey] = labelValue
+
+	return newSelector
+}
+
+// AddLabelToSelector returns a selector with the given key and value added to the given selector's MatchLabels.
+func AddLabelToSelector(selector *LabelSelector, labelKey, labelValue string) *LabelSelector {
+	if labelKey == "" {
+		// Don't need to add a label.
+		return selector
+	}
+	if selector.MatchLabels == nil {
+		selector.MatchLabels = make(map[string]string)
+	}
+	selector.MatchLabels[labelKey] = labelValue
+	return selector
+}
+
+// SelectorHasLabel checks if the given selector contains the given label key in its MatchLabels
+func SelectorHasLabel(selector *LabelSelector, labelKey string) bool {
+	return len(selector.MatchLabels[labelKey]) > 0
+}