Merge branch 'neilalexander/rsinputfifo' into neilalexander/rsinputfifo2

roomserver/internal/input/input_fifo.go

@@ -5,7 +5,7 @@ import (
 )
 
 type fifoQueue struct {
-	frames []*inputTask
+	tasks  []*inputTask
 	count  int
 	mutex  sync.Mutex
 	notifs chan struct{}
@@ -18,40 +18,44 @@ func newFIFOQueue() *fifoQueue {
 	return q
 }
 
-func (q *fifoQueue) push(frame *inputTask) bool {
+func (q *fifoQueue) push(frame *inputTask) {
 	q.mutex.Lock()
 	defer q.mutex.Unlock()
-	q.frames = append(q.frames, frame)
+	q.tasks = append(q.tasks, frame)
 	q.count++
 	select {
 	case q.notifs <- struct{}{}:
 	default:
 	}
-	return true
 }
 
+// pop returns the first item of the queue, if there is one.
+// The second return value will indicate if a task was returned.
+// You must check this value, even after calling wait().
 func (q *fifoQueue) pop() (*inputTask, bool) {
 	q.mutex.Lock()
 	defer q.mutex.Unlock()
 	if q.count == 0 {
 		return nil, false
 	}
-	frame := q.frames[0]
+	frame := q.tasks[0]
-	q.frames[0] = nil
+	q.tasks[0] = nil
-	q.frames = q.frames[1:]
+	q.tasks = q.tasks[1:]
 	q.count--
 	if q.count == 0 {
 		// Force a GC of the underlying array, since it might have
 		// grown significantly if the queue was hammered for some reason
-		q.frames = nil
+		q.tasks = nil
 	}
 	return frame, true
 }
 
+// wait returns a channel which can be used to detect when an
+// item is waiting in the queue.
 func (q *fifoQueue) wait() <-chan struct{} {
 	q.mutex.Lock()
 	defer q.mutex.Unlock()
-	if q.count > 0 {
+	if q.count > 0 && len(q.notifs) == 0 {
 		ch := make(chan struct{})
 		close(ch)
 		return ch