add hint fallthrough to compiler to avoid warning

src/apps/uclient/mainuclient.c

@@ -328,6 +328,7 @@ int main(int argc, char **argv)
 			passive_tcp = 1;
 			/* implies 'T': */
 			/* no break */
+			__attribute__((fallthrough));
 		case 'T':
 			relay_transport = STUN_ATTRIBUTE_TRANSPORT_TCP_VALUE;
 			break;
@@ -335,6 +336,7 @@ int main(int argc, char **argv)
 		  use_null_cipher = 1;
 		  /* implies 'S' */
 		  /* no break */
+		  __attribute__((fallthrough));
 		case 'S':
 			use_secure = 1;
 			break;

src/apps/uclient/uclient.c

@@ -261,6 +261,8 @@ int send_buffer(app_ur_conn_info *clnet_info, stun_buffer* message, int data_con
 					TURN_LOG_FUNC(TURN_LOG_LEVEL_INFO,"Socket write error 111.666: \n");
 					if (handle_socket_error())
 						break;
+
+					__attribute__((fallthrough));
 				case SSL_ERROR_SSL:
 				{
 					TURN_LOG_FUNC(TURN_LOG_LEVEL_INFO, "SSL write error: \n");
@@ -269,6 +271,8 @@ int send_buffer(app_ur_conn_info *clnet_info, stun_buffer* message, int data_con
 						"%s (%d)\n",
 						ERR_error_string(ERR_get_error(),buf),
 						SSL_get_error(ssl, len));
+
+					__attribute__((fallthrough));
 				}
 				default:
 					clnet_info->broken = 1;
@@ -457,12 +461,16 @@ int recv_buffer(app_ur_conn_info *clnet_info, stun_buffer* message, int sync, in
 							"Socket read error 111.999: \n");
 					if (handle_socket_error())
 						break;
+
+					__attribute__((fallthrough));
 				case SSL_ERROR_SSL: {
 					TURN_LOG_FUNC(TURN_LOG_LEVEL_INFO, "SSL write error: \n");
 					char buf[1024];
 					TURN_LOG_FUNC(TURN_LOG_LEVEL_INFO, "%s (%d)\n",
 							ERR_error_string(ERR_get_error(), buf),
 							SSL_get_error(ssl, rc));
+
+					__attribute__((fallthrough));
 				}
 				default:
 					clnet_info->broken = 1;
@@ -525,12 +533,16 @@ int recv_buffer(app_ur_conn_info *clnet_info, stun_buffer* message, int sync, in
 							"Socket read error 111.999: \n");
 					if (handle_socket_error())
 						break;
+
+					__attribute__((fallthrough));
 				case SSL_ERROR_SSL: {
 					TURN_LOG_FUNC(TURN_LOG_LEVEL_INFO, "SSL write error: \n");
 					char buf[1024];
 					TURN_LOG_FUNC(TURN_LOG_LEVEL_INFO, "%s (%d)\n",
 							ERR_error_string(ERR_get_error(), buf),
 							SSL_get_error(ssl, rc));
+
+					__attribute__((fallthrough));
 				}
 				default:
 					clnet_info->broken = 1;

src/server/ns_turn_server.c

@@ -1152,6 +1152,7 @@ static int handle_turn_allocate(turn_turnserver *server,
 					*reason = (const u08bits *)"Even Port cannot be used with Dual Allocation";
 					break;
 				}
+				__attribute__((fallthrough));
 			case STUN_ATTRIBUTE_REQUESTED_ADDRESS_FAMILY: {
 				if(in_reservation_token) {
 					*err_code = 400;