Fix lwIP builds

fixes #3119 lwIP does not export ip_mreq by default, it requires enabling support for IGMP by setting LWIP_IGMP, with the associated extra stuff. Mongoose will print an error if mg_multicast_add() is called with no multicast support in lwIP.
2025-06-07 17:42:30 +08:00 · 2025-04-29 19:24:17 -03:00 · 2025-04-29 19:24:17 -03:00 · f618fe125c
commit f618fe125c
parent 8ab514fabc
2 changed files with 8 additions and 0 deletions
--- a/mongoose.c
+++ b/mongoose.c
@ -8394,11 +8394,15 @@ void mg_multicast_add(struct mg_connection *c, char *ip) {
  // TODO(): prvAllowIPPacketIPv4()
 #else
  // lwIP, Unix, Windows, Zephyr(, AzureRTOS ?)
+#if MG_ENABLE_LWIP && !LWIP_IGMP
+  MG_ERROR(("LWIP_IGMP not defined, no multicast support"));
+#else
  struct ip_mreq mreq;
  mreq.imr_multiaddr.s_addr = inet_addr(ip);
  mreq.imr_interface.s_addr = mg_htonl(INADDR_ANY);
  setsockopt(FD(c), IPPROTO_IP, IP_ADD_MEMBERSHIP, (char *) &mreq, sizeof(mreq));
 #endif
+#endif
 }

 bool mg_open_listener(struct mg_connection *c, const char *url) {
--- a/src/sock.c
+++ b/src/sock.c
@ -184,11 +184,15 @@ void mg_multicast_add(struct mg_connection *c, char *ip) {
  // TODO(): prvAllowIPPacketIPv4()
 #else
  // lwIP, Unix, Windows, Zephyr(, AzureRTOS ?)
+#if MG_ENABLE_LWIP && !LWIP_IGMP
+  MG_ERROR(("LWIP_IGMP not defined, no multicast support"));
+#else
  struct ip_mreq mreq;
  mreq.imr_multiaddr.s_addr = inet_addr(ip);
  mreq.imr_interface.s_addr = mg_htonl(INADDR_ANY);
  setsockopt(FD(c), IPPROTO_IP, IP_ADD_MEMBERSHIP, (char *) &mreq, sizeof(mreq));
 #endif
+#endif
 }

 bool mg_open_listener(struct mg_connection *c, const char *url) {