WiFi udp Multicast

libraries/WiFi/src/SecSocket.cpp

@@ -124,6 +124,32 @@ bool Socket::connect(const char *host, uint16_t port) {
     return connect(&address);
 }
 
+
+bool Socket::joinMulticastGroup(IPAddress multicastIP, IPAddress localIP) {
+    cy_socket_ip_mreq_t mreq;
+    mreq.multi_addr.version = CY_SOCKET_IP_VER_V4;
+    mreq.multi_addr.ip.v4 = (multicastIP[3] << 24) | (multicastIP[2] << 16) |
+        (multicastIP[1] << 8) | multicastIP[0];
+    mreq.if_addr.version = CY_SOCKET_IP_VER_V4;
+    mreq.if_addr.ip.v4 = (localIP[3] << 24) | (localIP[2] << 16) |
+        (localIP[1] << 8) | localIP[0];
+
+    cy_rslt_t result = cy_socket_setsockopt(
+        socket,
+        CY_SOCKET_SOL_IP,
+        CY_SOCKET_SO_JOIN_MULTICAST_GROUP,
+        &mreq,
+        sizeof(mreq)
+        );
+
+    if (result != CY_RSLT_SUCCESS) {
+        _status = SOCKET_STATUS_ERROR;
+        _last_error = result;
+        return false;
+    }
+    return true;
+}
+
 void Socket::listen(int max_connections) {
     _last_error = cy_socket_listen(socket, max_connections);
     socket_assert(_last_error);

libraries/WiFi/src/SecSocket.h

@@ -39,6 +39,7 @@ class Socket {
     void bind(uint16_t port);
     bool connect(IPAddress ip, uint16_t port);
     bool connect(const char *host, uint16_t port);
+    bool joinMulticastGroup(IPAddress multicastIP, IPAddress localIP);
 
     void listen(int max_connections);
     bool accept(Socket & client_socket);

libraries/WiFi/src/WiFiUdp.cpp

@@ -1,6 +1,4 @@
 #include "WiFiUdp.h"
-#include <Arduino.h>
-
 
 #define udp_assert(cy_ret)   if (cy_ret != CY_RSLT_SUCCESS) { \
             _status = SOCKET_STATUS_ERROR; \
@@ -18,24 +16,39 @@ WiFiUDP::WiFiUDP() :
     _port(0) {
 }
 
-uint8_t WiFiUDP::begin(uint16_t port) {
-    // Initialize the socket for UDP
+uint8_t WiFiUDP::beginInternal(uint16_t port, IPAddress multicastIP) {
+
     socket.begin(SOCKET_PROTOCOL_UDP);
     if (socket.status() != SOCKET_STATUS_CREATED) {
         return 0;
     }
 
     socket.setReceiveOptCallback(receiveCallback, this);
 
-    // Bind the socket to the specified port
     socket.bind(port);
     if (socket.status() != SOCKET_STATUS_BOUND) {
         return 0;
+    }
+
+    if (multicastIP != IPAddress(0, 0, 0, 0)) {
+        IPAddress local_ip = WiFi.localIP(); // Get the local IP address
 
+        // Bind the socket to the specified multicast address and port
+        cy_rslt_t result = socket.joinMulticastGroup(multicastIP, local_ip);
+        udp_assert_raise(result);
     }
+
     return socket.status(); // Return the socket status
 }
 
+uint8_t WiFiUDP::begin(uint16_t port) {
+    // Start the UDP socket on the specified port
+    return beginInternal(port, IPAddress(0, 0, 0, 0));
+}
+
+uint8_t WiFiUDP::beginMulticast(IPAddress ip, uint16_t port) {
+    return beginInternal(port, ip);
+}
 
 void WiFiUDP::stop() {
     socket.end();

libraries/WiFi/src/WiFiUdp.h

@@ -16,6 +16,7 @@ class WiFiUDP: public arduino::UDP {
 
     WiFiUDP();
     uint8_t begin(uint16_t);
+    uint8_t beginMulticast(IPAddress, uint16_t);
     void stop();
     int beginPacket(IPAddress ip, uint16_t port);
     int beginPacket(const char *host, uint16_t port);
@@ -38,6 +39,7 @@ class WiFiUDP: public arduino::UDP {
 private:
     Socket socket;
 
+    uint8_t beginInternal(uint16_t port, IPAddress multicastIP = IPAddress());
     static cy_rslt_t receiveCallback(cy_socket_t socket_handle, void *arg);
 
     typedef struct {