MT#55283 add open_v46_socket()

Opens a generic socket supporting both IPv4 and IPv6, useful for
outgoing connections.

Change-Id: I2502653d481479b9c13a5f66ed5929723e9db9b3

lib/socket.c

@@ -725,6 +725,20 @@ fail:
 	return -1;
 }
 
+int open_v46_socket(socket_t *r, int type) {
+	sockfamily_t *fam = &__socket_families[SF_IP6];
+
+	if (__socket(r, type, fam)) {
+		__C_DBG("open socket fail, fd=%d", r->fd);
+		return -1;
+	}
+
+	nonblock(r->fd);
+	ipv6only(r->fd, 0);
+
+	return 0;
+}
+
 void dummy_socket(socket_t *r, const sockaddr_t *sa) {
 	ZERO(*r);
 	r->fd = -1;

lib/socket.h

@@ -214,6 +214,7 @@ INLINE int socket_cpu_affinity(socket_t *s, int cpu) {
 void socket_init(void);
 
 int open_socket(socket_t *r, int type, unsigned int port, const sockaddr_t *);
+int open_v46_socket(socket_t *r, int type);
 int connect_socket(socket_t *r, int type, const endpoint_t *ep);
 int connect_socket_nb(socket_t *r, int type, const endpoint_t *ep); // 1 == in progress
 int connect_socket_retry(socket_t *r); // retries connect() while in progress