聊聊gost的GoUnterminated

Posted 2021-10-05 codecraft

序

本文主要研究一下gost的GoUnterminated

GoUnterminated

gost/runtime/goroutine.go

// GoUnterminated is used for which goroutine wanna long live as its process.
// @period: sleep time duration after panic to defeat @handle panic so frequently. if it is not positive,
//          the @handle will be invoked asap after panic.
func GoUnterminated(handle func(), wg *sync.WaitGroup, ignoreRecover bool, period time.Duration) {
    GoSafely(wg,
        ignoreRecover,
        handle,
        func(r interface{}) {
            if period > 0 {
                time.Sleep(period)
            }
            GoUnterminated(handle, wg, ignoreRecover, period)
        },
    )
}

GoUnterminated方法提供handle、WaitGroup、ignoreRecover、period参数，其内部使用的是GoSafely，只是catchFunc是内置的；catchFunc对于period大于0的会sleep一下，之后还是执行GoUnterminated，这样子在handle出错(panic)的时候会一直递归循环下去

实例

gost/runtime/goroutine_test.go

func TestGoUnterminated(t *testing.T) {
    times := uint64(1)
    var wg sync.WaitGroup
    GoUnterminated(
        func() {
            if atomic.AddUint64(&times, 1) == 2 {
                panic("hello")
            }
        },
        &wg,
        false,
        1e8,
    )
    wg.Wait()
    assert.True(t, atomic.LoadUint64(&times) == 3)

    GoUnterminated(func() {
        atomic.AddUint64(&times, 1)
    },
        nil,
        false,
        1e8,
    )
    time.Sleep(1e9)
    assert.True(t, atomic.LoadUint64(&times) == 4)
}

这里模拟了一下handler在times为1的时候产生panic，以及handler不产生panic就立刻结束的场景

小结

gost提供了GoSafely方法，该方法提供handle、WaitGroup、ignoreRecover、period参数，其内部使用的是GoSafely，只是catchFunc是内置的；catchFunc对于period大于0的会sleep一下，之后还是执行GoUnterminated，这样子在handle出错(panic)的时候会一直递归循环下去。

doc

• gost