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// Copyright 2018 Google LLC
//
// 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 gate_test
import (
"sync"
"testing"
"time"
"gvisor.googlesource.com/gvisor/pkg/gate"
)
func TestBasicEnter(t *testing.T) {
var g gate.Gate
if !g.Enter() {
t.Fatalf("Failed to enter when it should be allowed")
}
g.Leave()
g.Close()
if g.Enter() {
t.Fatalf("Allowed to enter when it should fail")
}
}
func enterFunc(t *testing.T, g *gate.Gate, enter, leave, reenter chan struct{}, done1, done2, done3 *sync.WaitGroup) {
// Wait until instructed to enter.
<-enter
if !g.Enter() {
t.Errorf("Failed to enter when it should be allowed")
}
done1.Done()
// Wait until instructed to leave.
<-leave
g.Leave()
done2.Done()
// Wait until instructed to reenter.
<-reenter
if g.Enter() {
t.Errorf("Allowed to enter when it should fail")
}
done3.Done()
}
func TestConcurrentEnter(t *testing.T) {
var g gate.Gate
var done1, done2, done3 sync.WaitGroup
// Create 1000 worker goroutines.
enter := make(chan struct{})
leave := make(chan struct{})
reenter := make(chan struct{})
done1.Add(1000)
done2.Add(1000)
done3.Add(1000)
for i := 0; i < 1000; i++ {
go enterFunc(t, &g, enter, leave, reenter, &done1, &done2, &done3)
}
// Tell them all to enter, then leave.
close(enter)
done1.Wait()
close(leave)
done2.Wait()
// Close the gate, then have the workers try to enter again.
g.Close()
close(reenter)
done3.Wait()
}
func closeFunc(g *gate.Gate, done chan struct{}) {
g.Close()
close(done)
}
func TestCloseWaits(t *testing.T) {
var g gate.Gate
// Enter 10 times.
for i := 0; i < 10; i++ {
if !g.Enter() {
t.Fatalf("Failed to enter when it should be allowed")
}
}
// Launch closer. Check that it doesn't complete.
done := make(chan struct{})
go closeFunc(&g, done)
for i := 0; i < 10; i++ {
select {
case <-done:
t.Fatalf("Close function completed too soon")
case <-time.After(100 * time.Millisecond):
}
g.Leave()
}
// Now the closer must complete.
<-done
}
func TestMultipleSerialCloses(t *testing.T) {
var g gate.Gate
// Enter 10 times.
for i := 0; i < 10; i++ {
if !g.Enter() {
t.Fatalf("Failed to enter when it should be allowed")
}
}
// Launch closer. Check that it doesn't complete.
done := make(chan struct{})
go closeFunc(&g, done)
for i := 0; i < 10; i++ {
select {
case <-done:
t.Fatalf("Close function completed too soon")
case <-time.After(100 * time.Millisecond):
}
g.Leave()
}
// Now the closer must complete.
<-done
// Close again should not block.
done = make(chan struct{})
go closeFunc(&g, done)
select {
case <-done:
case <-time.After(2 * time.Second):
t.Fatalf("Second Close is blocking")
}
}
func worker(g *gate.Gate, done *sync.WaitGroup) {
for {
if !g.Enter() {
break
}
g.Leave()
}
done.Done()
}
func TestConcurrentAll(t *testing.T) {
var g gate.Gate
var done sync.WaitGroup
// Launch 1000 goroutines to concurrently enter/leave.
done.Add(1000)
for i := 0; i < 1000; i++ {
go worker(&g, &done)
}
// Wait for the goroutines to do some work, then close the gate.
time.Sleep(2 * time.Second)
g.Close()
// Wait for all of them to complete.
done.Wait()
}
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