WIP have peer actors queue packets, temporarily a single simple FIFO queue with head drop

src/yggdrasil/packetqueue.go

@@ -0,0 +1,39 @@
+package yggdrasil
+
+import "github.com/yggdrasil-network/yggdrasil-go/src/util"
+
+// TODO take max size from config
+const MAX_PACKET_QUEUE_SIZE = 1048576 // 1 MB
+
+// TODO separate queues per e.g. traffic flow
+type packetQueue struct {
+	packets [][]byte
+	size    uint32
+}
+
+func (q *packetQueue) cleanup() {
+	for q.size > MAX_PACKET_QUEUE_SIZE {
+		if packet, success := q.pop(); success {
+			util.PutBytes(packet)
+		} else {
+			panic("attempted to drop packet from empty queue")
+			break
+		}
+	}
+}
+
+func (q *packetQueue) push(packet []byte) {
+	q.packets = append(q.packets, packet)
+	q.size += uint32(len(packet))
+	q.cleanup()
+}
+
+func (q *packetQueue) pop() ([]byte, bool) {
+	if len(q.packets) > 0 {
+		packet := q.packets[0]
+		q.packets = q.packets[1:]
+		q.size -= uint32(len(packet))
+		return packet, true
+	}
+	return nil, false
+}