selftests/bpf: Add start_server_addr helper

In order to pair up with connect_to_addr(), this patch adds a new helper
start_server_addr(), which is a wrapper of __start_server(). It accepts
an argument 'addr' of 'struct sockaddr_storage' type instead of a string
type argument like start_server(), and a network_helper_opts argument as
the last one.
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Link: https://lore.kernel.org/r/2f01d48fa026467926738debe554ac452c19b86f.1713427236.git.tanggeliang@kylinos.cnSigned-off-by: Martin KaFai Lau <martin.lau@kernel.org>

tools/testing/selftests/bpf/network_helpers.c

@@ -52,6 +52,8 @@ struct ipv6_packet pkt_v6 = {
 	.tcp.doff = 5,
 };
 
+static const struct network_helper_opts default_opts;
+
 int settimeo(int fd, int timeout_ms)
 {
 	struct timeval timeout = { .tv_sec = 3 };
@@ -185,6 +187,16 @@ int *start_reuseport_server(int family, int type, const char *addr_str,
 	return NULL;
 }
 
+int start_server_addr(int type, const struct sockaddr_storage *addr, socklen_t len,
+		      const struct network_helper_opts *opts)
+{
+	if (!opts)
+		opts = &default_opts;
+
+	return __start_server(type, 0, (struct sockaddr *)addr, len,
+			      opts->timeout_ms, 0);
+}
+
 void free_fds(int *fds, unsigned int nr_close_fds)
 {
 	if (fds) {
@@ -278,8 +290,6 @@ int connect_to_addr(const struct sockaddr_storage *addr, socklen_t addrlen, int
 	return -1;
 }
 
-static const struct network_helper_opts default_opts;
-
 int connect_to_fd_opts(int server_fd, const struct network_helper_opts *opts)
 {
 	struct sockaddr_storage addr;

tools/testing/selftests/bpf/network_helpers.h

@@ -53,6 +53,8 @@ int start_mptcp_server(int family, const char *addr, __u16 port,
 int *start_reuseport_server(int family, int type, const char *addr_str,
 			    __u16 port, int timeout_ms,
 			    unsigned int nr_listens);
+int start_server_addr(int type, const struct sockaddr_storage *addr, socklen_t len,
+		      const struct network_helper_opts *opts);
 void free_fds(int *fds, unsigned int nr_close_fds);
 int connect_to_addr(const struct sockaddr_storage *addr, socklen_t len, int type);
 int connect_to_fd(int server_fd, int timeout_ms);