Merge pull request #1691 from G10h4ck/fixup_brodcastdiscovery

Fix some bugs in broadcast discovery

libretroshare/src/retroshare/rsbroadcastdiscovery.h

@@ -107,5 +107,45 @@ public:
 	 */
 	virtual std::vector<RsBroadcastDiscoveryResult> getDiscoveredPeers() = 0;
 
+	/**
+	 * @brief Check if multicast listening is enabled
+	 * @jsonapi{development}
+	 * On some platforms such as Android multicast listening, which is needed
+	 * for broadcast discovery, is not enabled by default at WiFi driver level
+	 * @see enableMulticastListening, so this method check if it is enabled.
+	 * On platforms that are not expected to have such a limitation this method
+	 * always return true.
+	 * @return true if enabled, false otherwise.
+	 */
+	virtual bool isMulticastListeningEnabled() = 0;
+
+	/**
+	 * @brief On platforms that need it enable low level multicast listening
+	 * @jsonapi{development}
+	 * On Android and potencially other mobile platforms, WiFi drivers are
+	 * configured by default to discard any packet that is not directed to the
+	 * unicast mac address of the interface, this way they could save some
+	 * battery but breaks anything that is not unicast, such as broadcast
+	 * discovery. On such platforms this method enable low level multicast
+	 * listening so we can receive advertisement from same broadcast domain
+	 * nodes.
+	 * On platforms without such limitation does nothing and always return
+	 * false.
+	 * It is exposed as a public API so the UI can decide the right equilibrium
+	 * between discoverability and battery saving.
+	 * @return true if multicast listening has been enabled due to this call,
+	 *	false otherwise.
+	 */
+	virtual bool enableMulticastListening() = 0;
+
+	/**
+	 * @brief Disable multicast listening
+	 * @jsonapi{development}
+	 * The opposite of @see enableMulticastListening.
+	 * @return true if multicast listening has been disabled due to this call,
+	 *	false otherwise.
+	 */
+	virtual bool disableMulticastListening() = 0;
+
 	virtual ~RsBroadcastDiscovery();
 };