<-messageChanmessageChan
但是,这个StackOverflow 问题让我害怕导致无意中的死锁。
我做了什么:
chan int<-chanmap[int]boolt.Fatallen(map[int]bool)
chan
代码
main_test.go
package main
import (
"log"
"sync"
"testing"
)
type MapMux struct {
sync.RWMutex
m map[int]bool
sync.WaitGroup
}
func (mux *MapMux) AddInt(i int) {
mux.RLock()
if _, isExist := mux.m[i]; isExist {
log.Fatal("race condition")
}
mux.RUnlock()
mux.Lock()
mux.m[i] = true
mux.Unlock()
mux.Done()
}
func TestChanRaceCondition(t *testing.T) {
l := 1000
c := make(chan int, l)
defer close(c)
for i := 0; i < l; i++ {
c <- i
}
mux := MapMux{sync.RWMutex{}, map[int]bool{}, sync.WaitGroup{}}
mux.Add(l)
for i := 0; i < 100; i++ {
go func(key int) {
for {
payload := <-c
log.Printf("go%d: %d", key, payload)
mux.AddInt(payload)
}
}(i)
}
mux.Wait()
if len(mux.m) != l {
t.Fatal("expected len:", l, ", actual len:", len(mux.m))
}
}
map[int]booldefer close(c)
无论如何,这就是我学到的。希望这对新的 Golangers 有所帮助。
学习到教训了:
val, isOpen := <-chanisOpenfalsesync.RWMutex.RLock()
func (mux *MapMux) AddInt(i int) {
mux.RLock()
if _, isExist := mux.m[i]; isExist {
log.Fatal("race condition")
}
mux.RUnlock()
mux.Lock()
if _, isExist := mux.m[i]; isExist {
log.Fatal("race condition")
}
mux.m[i] = true
mux.Unlock()
mux.Done()
}