add protocol.{Min,Max}ProtocolNumber

protocol/minmax.go

@@ -0,0 +1,17 @@
+package protocol
+
+// MaxPacketNumber returns the max packet number
+func MaxPacketNumber(a, b PacketNumber) PacketNumber {
+	if a > b {
+		return a
+	}
+	return b
+}
+
+// MinPacketNumber returns the min packet number
+func MinPacketNumber(a, b PacketNumber) PacketNumber {
+	if a < b {
+		return a
+	}
+	return b
+}