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// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package net
import (
"math/rand"
"runtime"
"testing"
"time"
)
func TestMutexLock(t *testing.T) {
var mu fdMutex
if !mu.Incref() {
t.Fatal("broken")
}
if mu.Decref() {
t.Fatal("broken")
}
if !mu.RWLock(true) {
t.Fatal("broken")
}
if mu.RWUnlock(true) {
t.Fatal("broken")
}
if !mu.RWLock(false) {
t.Fatal("broken")
}
if mu.RWUnlock(false) {
t.Fatal("broken")
}
}
func TestMutexClose(t *testing.T) {
var mu fdMutex
if !mu.IncrefAndClose() {
t.Fatal("broken")
}
if mu.Incref() {
t.Fatal("broken")
}
if mu.RWLock(true) {
t.Fatal("broken")
}
if mu.RWLock(false) {
t.Fatal("broken")
}
if mu.IncrefAndClose() {
t.Fatal("broken")
}
}
func TestMutexCloseUnblock(t *testing.T) {
c := make(chan bool)
var mu fdMutex
mu.RWLock(true)
for i := 0; i < 4; i++ {
go func() {
if mu.RWLock(true) {
t.Error("broken")
return
}
c <- true
}()
}
// Concurrent goroutines must not be able to read lock the mutex.
time.Sleep(time.Millisecond)
select {
case <-c:
t.Fatal("broken")
default:
}
mu.IncrefAndClose() // Must unblock the readers.
for i := 0; i < 4; i++ {
select {
case <-c:
case <-time.After(10 * time.Second):
t.Fatal("broken")
}
}
if mu.Decref() {
t.Fatal("broken")
}
if !mu.RWUnlock(true) {
t.Fatal("broken")
}
}
func TestMutexPanic(t *testing.T) {
ensurePanics := func(f func()) {
defer func() {
if recover() == nil {
t.Fatal("does not panic")
}
}()
f()
}
var mu fdMutex
ensurePanics(func() { mu.Decref() })
ensurePanics(func() { mu.RWUnlock(true) })
ensurePanics(func() { mu.RWUnlock(false) })
ensurePanics(func() { mu.Incref(); mu.Decref(); mu.Decref() })
ensurePanics(func() { mu.RWLock(true); mu.RWUnlock(true); mu.RWUnlock(true) })
ensurePanics(func() { mu.RWLock(false); mu.RWUnlock(false); mu.RWUnlock(false) })
// ensure that it's still not broken
mu.Incref()
mu.Decref()
mu.RWLock(true)
mu.RWUnlock(true)
mu.RWLock(false)
mu.RWUnlock(false)
}
func TestMutexStress(t *testing.T) {
P := 8
N := int(1e6)
if testing.Short() {
P = 4
N = 1e4
}
defer runtime.GOMAXPROCS(runtime.GOMAXPROCS(P))
done := make(chan bool)
var mu fdMutex
var readState [2]uint64
var writeState [2]uint64
for p := 0; p < P; p++ {
go func() {
r := rand.New(rand.NewSource(rand.Int63()))
for i := 0; i < N; i++ {
switch r.Intn(3) {
case 0:
if !mu.Incref() {
t.Error("broken")
return
}
if mu.Decref() {
t.Error("broken")
return
}
case 1:
if !mu.RWLock(true) {
t.Error("broken")
return
}
// Ensure that it provides mutual exclusion for readers.
if readState[0] != readState[1] {
t.Error("broken")
return
}
readState[0]++
readState[1]++
if mu.RWUnlock(true) {
t.Error("broken")
return
}
case 2:
if !mu.RWLock(false) {
t.Error("broken")
return
}
// Ensure that it provides mutual exclusion for writers.
if writeState[0] != writeState[1] {
t.Error("broken")
return
}
writeState[0]++
writeState[1]++
if mu.RWUnlock(false) {
t.Error("broken")
return
}
}
}
done <- true
}()
}
for p := 0; p < P; p++ {
<-done
}
if !mu.IncrefAndClose() {
t.Fatal("broken")
}
if !mu.Decref() {
t.Fatal("broken")
}
}
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