Golang atomic.SwapInt32函數代碼示例

func (s *Semaphore) AcquireTimeout(timeout time.Duration) bool {
	done := make(chan bool, 1)
	// Gate used to communicate between the threads and decide what the result
	// is. If the main thread decides, we have timed out, otherwise we succeed.
	decided := new(int32)
	go func() {
		s.Acquire()
		if atomic.SwapInt32(decided, 1) == 0 {
			done <- true
		} else {
			// If we already decided the result, and this thread did not win
			s.Release()
		}
	}()
	select {
	case <-done:
		return true
	case <-time.NewTimer(timeout).C:
		if atomic.SwapInt32(decided, 1) == 1 {
			// The other thread already decided the result
			return true
		}
		return false
	}
}

func watchUpdate(kv kvdb.Kvdb, data *watchData) error {
	var err error
	var kvp *kvdb.KVPair

	data.reader, data.writer = 0, 0
	atomic.AddInt32(&data.writer, 1)
	// whichKey = 1 : key
	// whichKey = 0 : otherKey
	atomic.SwapInt32(&data.whichKey, 1)
	data.action = kvdb.KVCreate
	fmt.Printf("-")
	kvp, err = kv.Create(data.key, []byte("bar"), 0)
	for i := 0; i < data.iterations && err == nil; i++ {
		fmt.Printf("-")

		for data.writer != data.reader {
			time.Sleep(time.Millisecond * 100)
		}
		atomic.AddInt32(&data.writer, 1)
		data.action = kvdb.KVSet
		kvp, err = kv.Put(data.key, []byte("bar"), 0)

		data.updateIndex = kvp.KVDBIndex
		assert.NoError(data.t, err, "Unexpected error in Put")
	}

	fmt.Printf("-")
	for data.writer != data.reader {
		time.Sleep(time.Millisecond * 100)
	}
	atomic.AddInt32(&data.writer, 1)
	// Delete key
	data.action = kvdb.KVDelete
	kv.Delete(data.key)

	fmt.Printf("-")
	for data.writer != data.reader {
		time.Sleep(time.Millisecond * 100)
	}
	atomic.AddInt32(&data.writer, 1)

	atomic.SwapInt32(&data.whichKey, 0)
	data.action = kvdb.KVDelete
	// Delete otherKey
	kv.Delete(data.otherKey)

	fmt.Printf("-")
	for data.writer != data.reader {
		time.Sleep(time.Millisecond * 100)
	}
	atomic.AddInt32(&data.writer, 1)

	atomic.SwapInt32(&data.whichKey, 1)
	data.action = kvdb.KVCreate
	_, err = kv.Create(data.key, []byte(data.stop), 0)

	return err
}

func (b *Buffer) finishPut() {
	atomic.AddInt32(&b.ring.wpos, 1)
	atomic.CompareAndSwapInt32(&b.ring.wpos, b.ring.size, 0)

	atomic.SwapInt32(&b.readonly, 1)
	b.lock.Unlock()
}

func (this *AtomicBoolean) Set(val bool) bool {
	var b int32 = 0
	if val {
		b = 1
	}
	return atomic.SwapInt32((*int32)(this), b) != 0
}

func (mailbox *endpointWriterMailbox) processMessages() {
	//we are about to start processing messages, we can safely reset the message flag of the mailbox
	atomic.StoreInt32(&mailbox.hasMoreMessages, mailboxHasNoMessages)
	batchSize := mailbox.batchSize
	done := false

	for !done {
		if sysMsg, ok := mailbox.systemMailbox.Pop(); ok {

			first := sysMsg.(actor.SystemMessage)
			mailbox.systemInvoke(first)
		} else if userMsg, ok := mailbox.userMailbox.PopMany(batchSize); ok {

			mailbox.userInvoke(userMsg)
		} else {
			done = true
			break
		}
		runtime.Gosched()
	}

	//set mailbox to idle
	atomic.StoreInt32(&mailbox.schedulerStatus, mailboxIdle)
	//check if there are still messages to process (sent after the message loop ended)
	if atomic.SwapInt32(&mailbox.hasMoreMessages, mailboxHasNoMessages) == mailboxHasMoreMessages {
		mailbox.schedule()
	}

}

func (mailbox *unboundedMailbox) processMessages() {
	//we are about to start processing messages, we can safely reset the message flag of the mailbox
	atomic.StoreInt32(&mailbox.hasMoreMessages, mailboxHasNoMessages)

	done := false
	for !done {
		//process x messages in sequence, then exit
		for i := 0; i < mailbox.throughput; i++ {
			if sysMsg, ok := mailbox.systemMailbox.Pop(); ok {
				sys, _ := sysMsg.(SystemMessage)
				mailbox.systemInvoke(sys)
			} else if userMsg, ok := mailbox.userMailbox.Pop(); ok {

				mailbox.userInvoke(userMsg)
			} else {
				done = true
				break
			}
		}
		runtime.Gosched()
	}

	//set mailbox to idle
	atomic.StoreInt32(&mailbox.schedulerStatus, mailboxIdle)
	//check if there are still messages to process (sent after the message loop ended)
	if atomic.SwapInt32(&mailbox.hasMoreMessages, mailboxHasNoMessages) == mailboxHasMoreMessages {
		mailbox.schedule()
	}

}

// Implement kanzi.InputStream interface
func (this *CompressedInputStream) Close() error {
	if atomic.SwapInt32(&this.closed, 1) == 1 {
		return nil
	}

	if _, err := this.ibs.Close(); err != nil {
		return err
	}

	// Release resources
	this.maxIdx = 0
	this.data = EMPTY_BYTE_SLICE

	for i := range this.buffers {
		this.buffers[i] = EMPTY_BYTE_SLICE
	}

	for _, c := range this.syncChan {
		if c != nil {
			close(c)
		}
	}

	close(this.resChan)
	return nil
}

func (pc *SocketClient) Close() {
	pc.changes.Lock()
	defer pc.changes.Unlock()

	if atomic.SwapInt32(&pc.state, SocketClosed) != SocketClosed {
		close(pc.writeQueue)
	}
}

// functions for monitoring internals
func monitor(mon *mylib.Mmon, boss mylib.Boss) {
	// just pick up first sender all the time, kiss
	sender := boss.Senders[0]
	ticker := time.Tick(1000 * time.Millisecond)
	last := time.Now()
	for {
		select {
		case <-ticker:
			//			log("debug", fmt.Sprintf("sending to %s..", sender.host))
			curr_time := time.Now()
			if curr_time.Unix() > last.Unix() {
				send_mon_data(atomic.SwapInt32(&mon.Send, 0), atomic.SwapInt32(&mon.Rcv, 0), atomic.SwapInt32(&mon.Conn, 0), boss.Port, curr_time, sender)
				last = curr_time
			}
		}
	}
}

func (t *Terminal) Close() error {
	if atomic.SwapInt32(&t.closed, 1) != 0 {
		return nil
	}
	t.stopChan <- struct{}{}
	t.wg.Wait()
	return t.ExitRawMode()
}

func (c *Cache) monitor() {
	tick := time.Tick(10 * time.Second)
	start := time.Now()
	for {
		select {
		case <-tick:
			in := atomic.SwapInt32(&c.inCache, 0)
			out := atomic.SwapInt32(&c.outCache, 0)
			all := atomic.SwapInt32(&c.requestCount, 0)
			now := time.Now()
			delta := now.Sub(start).Nanoseconds()
			speed := int64(all) * 1000000000 / int64(delta)
			log.Printf("Speed %d. In: %d, Out: %d, All: %d\n", speed, in, out, all)
			start = now
		}
	}
}

func (b *Buffer) lastDo() {
	if b.index+1 == b.ring.size {
		atomic.StoreInt32(&b.ring.rpos, 0)
	} else {
		atomic.StoreInt32(&b.ring.rpos, b.index+1)
	}

	atomic.SwapInt32(&b.readonly, 0)
}

func (b *AtomicBool) Swap(v bool) bool {
	var n AtomicBool

	if v {
		n = TRUE
	}

	return atomic.SwapInt32((*int32)(unsafe.Pointer(b)), int32(n)) != int32(FALSE)
}

// Set sets the current node ID. If it is already set, the value must match.
func (n *NodeIDContainer) Set(ctx context.Context, val roachpb.NodeID) {
	if val <= 0 {
		log.Fatalf(ctx, "trying to set invalid NodeID: %d", val)
	}
	oldVal := atomic.SwapInt32(&n.nodeID, int32(val))
	if oldVal == 0 {
		log.Infof(ctx, "NodeID set to %d", val)
	} else if oldVal != int32(val) {
		log.Fatalf(ctx, "different NodeIDs set: %d, then %d", oldVal, val)
	}
}

func (t *Terminal) Close() error {
	if atomic.SwapInt32(&t.closed, 1) != 0 {
		return nil
	}
	if closer, ok := t.cfg.Stdin.(io.Closer); ok {
		closer.Close()
	}
	close(t.stopChan)
	t.wg.Wait()
	return t.ExitRawMode()
}