Add MG_F_ENABLE_BROADCAST option

PUBLISHED_FROM=293a54ab09e6879b6f0c36975a137eeaeff92098

docs/c-api/net.h/struct_mg_connection.md

@@ -59,6 +59,7 @@ signature: |
   #define MG_F_CLOSE_IMMEDIATELY (1 << 11)   /* Disconnect */
   #define MG_F_WEBSOCKET_NO_DEFRAG (1 << 12) /* Websocket specific */
   #define MG_F_DELETE_CHUNK (1 << 13)        /* HTTP specific */
+  #define MG_F_ENABLE_BROADCAST (1 << 14)    /* Allow broadcast address usage */
   
   #define MG_F_USER_1 (1 << 20) /* Flags left for application */
   #define MG_F_USER_2 (1 << 21)

mongoose.c

@@ -1679,7 +1679,7 @@ const char *c_strnstr(const char *s, const char *find, size_t slen) {
 /* Which flags can be pre-set by the user at connection creation time. */
 #define _MG_ALLOWED_CONNECT_FLAGS_MASK                                   \
   (MG_F_USER_1 | MG_F_USER_2 | MG_F_USER_3 | MG_F_USER_4 | MG_F_USER_5 | \
-   MG_F_USER_6 | MG_F_WEBSOCKET_NO_DEFRAG)
+   MG_F_USER_6 | MG_F_WEBSOCKET_NO_DEFRAG | MG_F_ENABLE_BROADCAST)
 /* Which flags should be modifiable by user's callbacks. */
 #define _MG_CALLBACK_MODIFIABLE_FLAGS_MASK                               \
   (MG_F_USER_1 | MG_F_USER_2 | MG_F_USER_3 | MG_F_USER_4 | MG_F_USER_5 | \
@@ -2789,6 +2789,11 @@ void mg_if_connect_udp(struct mg_connection *nc) {
     nc->err = errno ? errno : 1;
     return;
   }
+  if (nc->flags & MG_F_ENABLE_BROADCAST) {
+    int optval = 1;
+    setsockopt(nc->sock, SOL_SOCKET, SO_BROADCAST, (const char *) &optval,
+               sizeof(optval));
+  }
   nc->err = 0;
 }
 

mongoose.h

@@ -1263,6 +1263,7 @@ struct mg_connection {
 #define MG_F_CLOSE_IMMEDIATELY (1 << 11)   /* Disconnect */
 #define MG_F_WEBSOCKET_NO_DEFRAG (1 << 12) /* Websocket specific */
 #define MG_F_DELETE_CHUNK (1 << 13)        /* HTTP specific */
+#define MG_F_ENABLE_BROADCAST (1 << 14)    /* Allow broadcast address usage */
 
 #define MG_F_USER_1 (1 << 20) /* Flags left for application */
 #define MG_F_USER_2 (1 << 21)