golang利用channel实现线程同步互斥信号量

1、利用channel实现线程互斥

package main

import (
    "fmt"
    "sync"
)

var value int = 0

func add(ch chan struct{}, group *sync.WaitGroup) {
    ch <- struct{}{}
    value++
    <-ch
    group.Done()
}
func main() {
    var wg sync.WaitGroup
    var channel = make(chan struct{}, 1)
    wg.Add(10000)
    for i := 0; i < 10000; i++ {
        go add(channel, &wg)
    }
    wg.Wait()
    fmt.Println(value)
}

2、利用channel实现线程同步

package main

import (
    "fmt"
    "sync"
)

func funcA(ch chan struct{},group *sync.WaitGroup)  {
    fmt.Println("A函数执行完毕")
    ch<- struct{}{}
    group.Done()
}

func funcB(ch chan struct{},group *sync.WaitGroup)  {
    <-ch
    fmt.Println("B函数执行完毕")
    group.Done()
}
func main() {
    var wg sync.WaitGroup
    wg.Add(2)
    ch:=make(chan struct{})
    go funcA(ch,&wg)
    go funcB(ch,&wg)
    wg.Wait()
}

3、利用channel实现信号量

package main

import (
    "fmt"
    "sync"
)

func funcA(ch chan struct{},group *sync.WaitGroup)  {
    <-ch
    fmt.Println("A函数执行完毕")
    ch<- struct{}{}
    group.Done()
}

func funcB(ch chan struct{},group *sync.WaitGroup)  {
    <-ch
    fmt.Println("B函数执行完毕")
    ch<- struct{}{}
    group.Done()
}
func main() {
    var wg sync.WaitGroup
    wg.Add(2)
    ch:=make(chan struct{},1)
    ch<- struct{}{}
    go funcA(ch,&wg)
    go funcB(ch,&wg)
    wg.Wait()
}