introduce unsubscribing from universes

wiflash_esp32/src/lib/sacn/receiver-esp.cpp

@@ -38,13 +38,24 @@ EspReceiver::EspReceiver()
                          std::placeholders::_1));
 }
 
-void EspReceiver::subscribe(uint16_t num) {
+void EspReceiver::subscribe(const uint16_t num) {
+  if (universe(num))  // already subscribed
+    return;
+  ESP_LOGI(TAG, "Subscribing to universe # %d", num);
   Receiver::subscribe(num);
   // listen multicast; works for unicast too
   udp.listenMulticast(IPv4MulticastAddress(num),
                       ACN_SDT_MULTICAST_PORT);
 }
 
+void EspReceiver::unsubscribe(const uint16_t num) {
+  if (!universe(num)) // not subscribed
+    return;
+  ESP_LOGI(TAG, "Unubscribing from universe # %d", num);
+  Receiver::unsubscribe(num);
+  // AsyncUDP has no way to unsubscribe IGMP?
+}
+
 void EspReceiver::udpHandler(AsyncUDPPacket udp) {
   // Expecting IANA registered Session Data Transport traffic
   if (!udp.localPort() == ACN_SDT_MULTICAST_PORT)

wiflash_esp32/src/lib/sacn/receiver-esp.h

@@ -55,7 +55,8 @@ class EspReceiver
 {
   public:
     EspReceiver();
-    void subscribe(uint16_t universe = 1);
+    virtual void subscribe(const uint16_t universe = 1);
+    virtual void unsubscribe(const uint16_t);
 
   private:
     AsyncUDP   udp;      // AsyncUDP

wiflash_esp32/src/lib/sacn/receiver.cpp

@@ -27,12 +27,15 @@
 
 namespace SACN {
 
-void Receiver::subscribe(const uint16_t universe) {
-  if (universes_.count(universe))
-    return;
-  universes_.emplace(universe, new SACN::Universe());
+void Receiver::subscribe(const uint16_t num) {
+  if (!universes_.count(num))
+    universes_.emplace(num, new SACN::Universe());
 }
 
+void Receiver::unsubscribe(const uint16_t num) {
+  if (universes_.count(num))
+    universes_.erase(num);
+}
 
 SACN::Universe * Receiver::universe(uint16_t universe) {
   if (universes_.count(universe))

wiflash_esp32/src/lib/sacn/receiver.h

@@ -34,7 +34,8 @@ class Receiver
 {
 public:
   Receiver() {};
-  void subscribe(const uint16_t universe);
+  virtual void subscribe(const uint16_t);
+  virtual void unsubscribe(const uint16_t);
   SACN::Universe * universe(uint16_t universe);
 
 protected: