Move scheduler code out of plugin directory.

This moves plugin/pkg/scheduler to pkg/scheduler and
plugin/cmd/kube-scheduler to cmd/kube-scheduler.

Bulk of the work was done with gomvpkg, except for kube-scheduler main
package.

pkg/scheduler/util/utils.go

@@ -0,0 +1,120 @@
+/*
+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"
+	"sort"
+
+	"k8s.io/api/core/v1"
+	"k8s.io/apiserver/pkg/util/feature"
+	"k8s.io/kubernetes/pkg/apis/scheduling"
+	"k8s.io/kubernetes/pkg/features"
+)
+
+const DefaultBindAllHostIP = "0.0.0.0"
+
+// GetUsedPorts returns the used host ports of Pods: if 'port' was used, a 'port:true' pair
+// will be in the result; but it does not resolve port conflict.
+func GetUsedPorts(pods ...*v1.Pod) map[string]bool {
+	ports := make(map[string]bool)
+	for _, pod := range pods {
+		for j := range pod.Spec.Containers {
+			container := &pod.Spec.Containers[j]
+			for k := range container.Ports {
+				podPort := &container.Ports[k]
+				// "0" is explicitly ignored in PodFitsHostPorts,
+				// which is the only function that uses this value.
+				if podPort.HostPort != 0 {
+					// user does not explicitly set protocol, default is tcp
+					portProtocol := podPort.Protocol
+					if podPort.Protocol == "" {
+						portProtocol = v1.ProtocolTCP
+					}
+
+					// user does not explicitly set hostIP, default is 0.0.0.0
+					portHostIP := podPort.HostIP
+					if podPort.HostIP == "" {
+						portHostIP = "0.0.0.0"
+					}
+
+					str := fmt.Sprintf("%s/%s/%d", portProtocol, portHostIP, podPort.HostPort)
+					ports[str] = true
+				}
+			}
+		}
+	}
+	return ports
+}
+
+// PodPriorityEnabled indicates whether pod priority feature is enabled.
+func PodPriorityEnabled() bool {
+	return feature.DefaultFeatureGate.Enabled(features.PodPriority)
+}
+
+// GetPodFullName returns a name that uniquely identifies a pod.
+func GetPodFullName(pod *v1.Pod) string {
+	// Use underscore as the delimiter because it is not allowed in pod name
+	// (DNS subdomain format).
+	return pod.Name + "_" + pod.Namespace
+}
+
+// GetPodPriority return priority of the given pod.
+func GetPodPriority(pod *v1.Pod) int32 {
+	if pod.Spec.Priority != nil {
+		return *pod.Spec.Priority
+	}
+	// When priority of a running pod is nil, it means it was created at a time
+	// that there was no global default priority class and the priority class
+	// name of the pod was empty. So, we resolve to the static default priority.
+	return scheduling.DefaultPriorityWhenNoDefaultClassExists
+}
+
+// SortableList is a list that implements sort.Interface.
+type SortableList struct {
+	Items    []interface{}
+	CompFunc LessFunc
+}
+
+// LessFunc is a function that receives two items and returns true if the first
+// item should be placed before the second one when the list is sorted.
+type LessFunc func(item1, item2 interface{}) bool
+
+var _ = sort.Interface(&SortableList{})
+
+func (l *SortableList) Len() int { return len(l.Items) }
+
+func (l *SortableList) Less(i, j int) bool {
+	return l.CompFunc(l.Items[i], l.Items[j])
+}
+
+func (l *SortableList) Swap(i, j int) {
+	l.Items[i], l.Items[j] = l.Items[j], l.Items[i]
+}
+
+// Sort sorts the items in the list using the given CompFunc. Item1 is placed
+// before Item2 when CompFunc(Item1, Item2) returns true.
+func (l *SortableList) Sort() {
+	sort.Sort(l)
+}
+
+// HigherPriorityPod return true when priority of the first pod is higher than
+// the second one. It takes arguments of the type "interface{}" to be used with
+// SortableList, but expects those arguments to be *v1.Pod.
+func HigherPriorityPod(pod1, pod2 interface{}) bool {
+	return GetPodPriority(pod1.(*v1.Pod)) > GetPodPriority(pod2.(*v1.Pod))
+}