unix: add uv_udp_set_broadcast() and uv_udp_set_multicast_ttl()

include/uv.h

@@ -631,6 +631,32 @@ UV_EXTERN int uv_udp_set_membership(uv_udp_t* handle,
     const char* multicast_addr, const char* interface_addr,
     uv_membership membership);
 
+/*
+ * Set the multicast ttl
+ *
+ * Arguments:
+ *  handle              UDP handle. Should have been initialized with
+ *                      `uv_udp_init`.
+ *  ttl                 1 through 255
+ *
+ * Returns:
+ *  0 on success, -1 on error.
+ */
+int uv_udp_set_multicast_ttl(uv_udp_t* handle, int ttl);
+
+/*
+ * Set broadcast on or off
+ *
+ * Arguments:
+ *  handle              UDP handle. Should have been initialized with
+ *                      `uv_udp_init`.
+ *  on                  1 for on, 0 for off
+ *
+ * Returns:
+ *  0 on success, -1 on error.
+ */
+int uv_udp_set_broadcast(uv_udp_t* handle, int on);
+
 /*
  * Send data. If the socket has not previously been bound with `uv_udp_bind`
  * or `uv_udp_bind6`, it is bound to 0.0.0.0 (the "all interfaces" address)

src/unix/udp.c

@@ -509,6 +509,24 @@ int uv_udp_set_membership(uv_udp_t* handle, const char* multicast_addr,
   return 0;
 }
 
+int uv_udp_set_multicast_ttl(uv_udp_t* handle, int ttl) {
+  if (setsockopt(handle->fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof ttl) == -1) {
+    uv__set_sys_error(handle->loop, errno);
+    return -1;
+  }
+
+  return 0;
+}
+
+int uv_udp_set_broadcast(uv_udp_t* handle, int on) {
+  if (setsockopt(handle->fd, SOL_SOCKET, SO_BROADCAST, &on, sizeof on) == -1) {
+    uv__set_sys_error(handle->loop, errno);
+    return -1;
+  }
+
+  return 0;
+}
+
 
 int uv_udp_getsockname(uv_udp_t* handle, struct sockaddr* name,
     int* namelen) {