1 files changed, 327 insertions, 0 deletions
diff --git a/vendor/k8s.io/apimachinery/pkg/util/clock/clock.go b/vendor/k8s.io/apimachinery/pkg/util/clock/clock.go
new file mode 100644
index 000000000..c303a212a
--- /dev/null
+++ b/vendor/k8s.io/apimachinery/pkg/util/clock/clock.go
@@ -0,0 +1,327 @@
+/*
+Copyright 2014 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 clock
+
+import (
+	"sync"
+	"time"
+)
+
+// Clock allows for injecting fake or real clocks into code that
+// needs to do arbitrary things based on time.
+type Clock interface {
+	Now() time.Time
+	Since(time.Time) time.Duration
+	After(d time.Duration) <-chan time.Time
+	NewTimer(d time.Duration) Timer
+	Sleep(d time.Duration)
+	Tick(d time.Duration) <-chan time.Time
+}
+
+var (
+	_ = Clock(RealClock{})
+	_ = Clock(&FakeClock{})
+	_ = Clock(&IntervalClock{})
+)
+
+// RealClock really calls time.Now()
+type RealClock struct{}
+
+// Now returns the current time.
+func (RealClock) Now() time.Time {
+	return time.Now()
+}
+
+// Since returns time since the specified timestamp.
+func (RealClock) Since(ts time.Time) time.Duration {
+	return time.Since(ts)
+}
+
+// Same as time.After(d).
+func (RealClock) After(d time.Duration) <-chan time.Time {
+	return time.After(d)
+}
+
+func (RealClock) NewTimer(d time.Duration) Timer {
+	return &realTimer{
+		timer: time.NewTimer(d),
+	}
+}
+
+func (RealClock) Tick(d time.Duration) <-chan time.Time {
+	return time.Tick(d)
+}
+
+func (RealClock) Sleep(d time.Duration) {
+	time.Sleep(d)
+}
+
+// FakeClock implements Clock, but returns an arbitrary time.
+type FakeClock struct {
+	lock sync.RWMutex
+	time time.Time
+
+	// waiters are waiting for the fake time to pass their specified time
+	waiters []fakeClockWaiter
+}
+
+type fakeClockWaiter struct {
+	targetTime    time.Time
+	stepInterval  time.Duration
+	skipIfBlocked bool
+	destChan      chan time.Time
+	fired         bool
+}
+
+func NewFakeClock(t time.Time) *FakeClock {
+	return &FakeClock{
+		time: t,
+	}
+}
+
+// Now returns f's time.
+func (f *FakeClock) Now() time.Time {
+	f.lock.RLock()
+	defer f.lock.RUnlock()
+	return f.time
+}
+
+// Since returns time since the time in f.
+func (f *FakeClock) Since(ts time.Time) time.Duration {
+	f.lock.RLock()
+	defer f.lock.RUnlock()
+	return f.time.Sub(ts)
+}
+
+// Fake version of time.After(d).
+func (f *FakeClock) After(d time.Duration) <-chan time.Time {
+	f.lock.Lock()
+	defer f.lock.Unlock()
+	stopTime := f.time.Add(d)
+	ch := make(chan time.Time, 1) // Don't block!
+	f.waiters = append(f.waiters, fakeClockWaiter{
+		targetTime: stopTime,
+		destChan:   ch,
+	})
+	return ch
+}
+
+// Fake version of time.NewTimer(d).
+func (f *FakeClock) NewTimer(d time.Duration) Timer {
+	f.lock.Lock()
+	defer f.lock.Unlock()
+	stopTime := f.time.Add(d)
+	ch := make(chan time.Time, 1) // Don't block!
+	timer := &fakeTimer{
+		fakeClock: f,
+		waiter: fakeClockWaiter{
+			targetTime: stopTime,
+			destChan:   ch,
+		},
+	}
+	f.waiters = append(f.waiters, timer.waiter)
+	return timer
+}
+
+func (f *FakeClock) Tick(d time.Duration) <-chan time.Time {
+	f.lock.Lock()
+	defer f.lock.Unlock()
+	tickTime := f.time.Add(d)
+	ch := make(chan time.Time, 1) // hold one tick
+	f.waiters = append(f.waiters, fakeClockWaiter{
+		targetTime:    tickTime,
+		stepInterval:  d,
+		skipIfBlocked: true,
+		destChan:      ch,
+	})
+
+	return ch
+}
+
+// Move clock by Duration, notify anyone that's called After, Tick, or NewTimer
+func (f *FakeClock) Step(d time.Duration) {
+	f.lock.Lock()
+	defer f.lock.Unlock()
+	f.setTimeLocked(f.time.Add(d))
+}
+
+// Sets the time.
+func (f *FakeClock) SetTime(t time.Time) {
+	f.lock.Lock()
+	defer f.lock.Unlock()
+	f.setTimeLocked(t)
+}
+
+// Actually changes the time and checks any waiters. f must be write-locked.
+func (f *FakeClock) setTimeLocked(t time.Time) {
+	f.time = t
+	newWaiters := make([]fakeClockWaiter, 0, len(f.waiters))
+	for i := range f.waiters {
+		w := &f.waiters[i]
+		if !w.targetTime.After(t) {
+
+			if w.skipIfBlocked {
+				select {
+				case w.destChan <- t:
+					w.fired = true
+				default:
+				}
+			} else {
+				w.destChan <- t
+				w.fired = true
+			}
+
+			if w.stepInterval > 0 {
+				for !w.targetTime.After(t) {
+					w.targetTime = w.targetTime.Add(w.stepInterval)
+				}
+				newWaiters = append(newWaiters, *w)
+			}
+
+		} else {
+			newWaiters = append(newWaiters, f.waiters[i])
+		}
+	}
+	f.waiters = newWaiters
+}
+
+// Returns true if After has been called on f but not yet satisfied (so you can
+// write race-free tests).
+func (f *FakeClock) HasWaiters() bool {
+	f.lock.RLock()
+	defer f.lock.RUnlock()
+	return len(f.waiters) > 0
+}
+
+func (f *FakeClock) Sleep(d time.Duration) {
+	f.Step(d)
+}
+
+// IntervalClock implements Clock, but each invocation of Now steps the clock forward the specified duration
+type IntervalClock struct {
+	Time     time.Time
+	Duration time.Duration
+}
+
+// Now returns i's time.
+func (i *IntervalClock) Now() time.Time {
+	i.Time = i.Time.Add(i.Duration)
+	return i.Time
+}
+
+// Since returns time since the time in i.
+func (i *IntervalClock) Since(ts time.Time) time.Duration {
+	return i.Time.Sub(ts)
+}
+
+// Unimplemented, will panic.
+// TODO: make interval clock use FakeClock so this can be implemented.
+func (*IntervalClock) After(d time.Duration) <-chan time.Time {
+	panic("IntervalClock doesn't implement After")
+}
+
+// Unimplemented, will panic.
+// TODO: make interval clock use FakeClock so this can be implemented.
+func (*IntervalClock) NewTimer(d time.Duration) Timer {
+	panic("IntervalClock doesn't implement NewTimer")
+}
+
+// Unimplemented, will panic.
+// TODO: make interval clock use FakeClock so this can be implemented.
+func (*IntervalClock) Tick(d time.Duration) <-chan time.Time {
+	panic("IntervalClock doesn't implement Tick")
+}
+
+func (*IntervalClock) Sleep(d time.Duration) {
+	panic("IntervalClock doesn't implement Sleep")
+}
+
+// Timer allows for injecting fake or real timers into code that
+// needs to do arbitrary things based on time.
+type Timer interface {
+	C() <-chan time.Time
+	Stop() bool
+	Reset(d time.Duration) bool
+}
+
+var (
+	_ = Timer(&realTimer{})
+	_ = Timer(&fakeTimer{})
+)
+
+// realTimer is backed by an actual time.Timer.
+type realTimer struct {
+	timer *time.Timer
+}
+
+// C returns the underlying timer's channel.
+func (r *realTimer) C() <-chan time.Time {
+	return r.timer.C
+}
+
+// Stop calls Stop() on the underlying timer.
+func (r *realTimer) Stop() bool {
+	return r.timer.Stop()
+}
+
+// Reset calls Reset() on the underlying timer.
+func (r *realTimer) Reset(d time.Duration) bool {
+	return r.timer.Reset(d)
+}
+
+// fakeTimer implements Timer based on a FakeClock.
+type fakeTimer struct {
+	fakeClock *FakeClock
+	waiter    fakeClockWaiter
+}
+
+// C returns the channel that notifies when this timer has fired.
+func (f *fakeTimer) C() <-chan time.Time {
+	return f.waiter.destChan
+}
+
+// Stop stops the timer and returns true if the timer has not yet fired, or false otherwise.
+func (f *fakeTimer) Stop() bool {
+	f.fakeClock.lock.Lock()
+	defer f.fakeClock.lock.Unlock()
+
+	newWaiters := make([]fakeClockWaiter, 0, len(f.fakeClock.waiters))
+	for i := range f.fakeClock.waiters {
+		w := &f.fakeClock.waiters[i]
+		if w != &f.waiter {
+			newWaiters = append(newWaiters, *w)
+		}
+	}
+
+	f.fakeClock.waiters = newWaiters
+
+	return !f.waiter.fired
+}
+
+// Reset resets the timer to the fake clock's "now" + d. It returns true if the timer has not yet
+// fired, or false otherwise.
+func (f *fakeTimer) Reset(d time.Duration) bool {
+	f.fakeClock.lock.Lock()
+	defer f.fakeClock.lock.Unlock()
+
+	active := !f.waiter.fired
+
+	f.waiter.fired = false
+	f.waiter.targetTime = f.fakeClock.time.Add(d)
+
+	return active
+}