Go 不安全编程
2022年1月18日|
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package unsafe_test import ( "fmt" "sync" "sync/atomic" "testing" "unsafe" ) type Customer struct { Name string Age int } /** * 不安全得数值类型转换 */ func TestUnsafe(t *testing.T) { i := 10 f := *(*float64)(unsafe.Pointer(&i)) t.Log(unsafe.Pointer(&i)) t.Log(f) } // The cases is suitable for unsafe type MyInt int /** * 合理的类型转换 */ func TestConvert(t *testing.T) { a := []int{1, 2, 3, 4} b := *(*[]MyInt)(unsafe.Pointer(&a)) t.Log(b) } //原子类型操作 func TestAtomic(t *testing.T) { var shareBufPtr unsafe.Pointer /** * 写入数据的方法 */ writeDataFn := func() { data := []int{} for i := 0; i < 100; i++ { data = append(data, i) } //为了线程安全使用 tomic.StorePointer 将 unsafe.Pointer(&data)的地址放入shareBufPtr atomic.StorePointer(&shareBufPtr, unsafe.Pointer(&data)) } /** * 打印数据得方法 */ readDataFn := func() { data := atomic.LoadPointer(&shareBufPtr) fmt.Println(data, *(*[]int)(data)) } writeDataFn() //先创建一条数据 var wg sync.WaitGroup for i := 0; i < 10; i++ { wg.Add(1) go func() { for i := 0; i < 10; i++ { writeDataFn() } wg.Done() }() wg.Add(1) go func() { for i := 0; i < 10; i++ { readDataFn() } wg.Done() }() } wg.Wait() } |
