Introduce generic osmo_stream_{cli,srv}_get_fd() API

The old osmo_stream_{cli,srv}_get_ofd() API only works for streams
in OSMO_FD mode.  However, it is legitimate for an application
wanting to get low-level access to the file descriptor, for example
to issue some {get,set}sockopt() calls on it.

Change-Id: Ib0737f21150f6ac8d524b92c7ddb098f2afdeaab
Related: OS#5753
---
M include/osmocom/netif/stream.h
M src/stream_cli.c
M src/stream_srv.c
3 files changed, 45 insertions(+), 6 deletions(-)

diff --git a/include/osmocom/netif/stream.h b/include/osmocom/netif/stream.h
index a24244c..218b635 100644
--- a/include/osmocom/netif/stream.h
+++ b/include/osmocom/netif/stream.h
@@ -64,6 +64,7 @@
 void *osmo_stream_srv_get_data(struct osmo_stream_srv *conn);
 struct osmo_stream_srv_link *osmo_stream_srv_get_master(struct osmo_stream_srv *conn);
 struct osmo_fd *osmo_stream_srv_get_ofd(struct osmo_stream_srv *srv);
+int osmo_stream_srv_get_fd(const struct osmo_stream_srv *srv);
 void osmo_stream_srv_destroy(struct osmo_stream_srv *conn);
 
 void osmo_stream_srv_set_flush_and_destroy(struct osmo_stream_srv *conn);
@@ -96,6 +97,7 @@
 void *osmo_stream_cli_get_data(struct osmo_stream_cli *cli);
 char *osmo_stream_cli_get_sockname(const struct osmo_stream_cli *cli);
 struct osmo_fd *osmo_stream_cli_get_ofd(struct osmo_stream_cli *cli);
+int osmo_stream_cli_get_fd(const struct osmo_stream_cli *cli);
 void osmo_stream_cli_set_connect_cb(struct osmo_stream_cli *cli, int (*connect_cb)(struct osmo_stream_cli *cli));
 void osmo_stream_cli_set_disconnect_cb(struct osmo_stream_cli *cli, int (*disconnect_cb)(struct osmo_stream_cli *cli));
 void osmo_stream_cli_set_read_cb(struct osmo_stream_cli *cli, int (*read_cb)(struct osmo_stream_cli *cli));
diff --git a/src/stream_cli.c b/src/stream_cli.c
index ef571cc..1e7ebeb 100644
--- a/src/stream_cli.c
+++ b/src/stream_cli.c
@@ -210,7 +210,11 @@
 	}
 }
 
-static inline int osmo_stream_cli_fd(const struct osmo_stream_cli *cli)
+/*! \brief Get file descriptor of the stream client socket
+ *  \param[in] cli Stream Client of which we want to obtain the file descriptor
+ *  \returns File descriptor or negative in case of error */
+int
+osmo_stream_cli_get_fd(const struct osmo_stream_cli *cli)
 {
 	switch (cli->mode) {
 	case OSMO_STREAM_MODE_OSMO_FD:
@@ -314,7 +318,7 @@
 #ifdef SO_NOSIGPIPE
 	int ret;
 	int val = 1;
-	ret = setsockopt(osmo_stream_cli_fd(cli), SOL_SOCKET, SO_NOSIGPIPE, (void *)&val, sizeof(val));
+	ret = setsockopt(osmo_stream_cli_get_fd(cli), SOL_SOCKET, SO_NOSIGPIPE, (void *)&val, sizeof(val));
 	if (ret < 0)
 		LOGSCLI(cli, LOGL_ERROR, "Failed setting SO_NOSIGPIPE: %s\n", strerror(errno));
 	return ret;
@@ -328,7 +332,7 @@
 	int error, ret = res;
 	socklen_t len = sizeof(error);
 
-	int fd = osmo_stream_cli_fd(cli);
+	int fd = osmo_stream_cli_get_fd(cli);
 	OSMO_ASSERT(fd >= 0);
 
 	if (ret < 0) {
@@ -347,7 +351,7 @@
 		osmo_fd_write_disable(&cli->ofd);
 
 	/* Update sockname based on socket info: */
-	osmo_sock_get_name_buf(cli->sockname, sizeof(cli->sockname), osmo_stream_cli_fd(cli));
+	osmo_sock_get_name_buf(cli->sockname, sizeof(cli->sockname), osmo_stream_cli_get_fd(cli));
 
 	LOGSCLI(cli, LOGL_INFO, "connection established\n");
 	cli->state = STREAM_CLI_STATE_CONNECTED;
@@ -683,7 +687,7 @@
 {
 	static char buf[OSMO_SOCK_NAME_MAXLEN];
 
-	osmo_sock_get_name_buf(buf, OSMO_SOCK_NAME_MAXLEN, osmo_stream_cli_fd(cli));
+	osmo_sock_get_name_buf(buf, OSMO_SOCK_NAME_MAXLEN, osmo_stream_cli_get_fd(cli));
 
 	return buf;
 }
@@ -837,7 +841,7 @@
 	int ret, fd = -1;
 
 	/* we are reconfiguring this socket, close existing first. */
-	if ((cli->flags & OSMO_STREAM_CLI_F_RECONF) && osmo_stream_cli_fd(cli) >= 0)
+	if ((cli->flags & OSMO_STREAM_CLI_F_RECONF) && osmo_stream_cli_get_fd(cli) >= 0)
 		osmo_stream_cli_close(cli);
 
 	cli->flags &= ~OSMO_STREAM_CLI_F_RECONF;
diff --git a/src/stream_srv.c b/src/stream_srv.c
index 36e21cc..42b04ad 100644
--- a/src/stream_srv.c
+++ b/src/stream_srv.c
@@ -838,6 +838,24 @@
 	return &conn->ofd;
 }
 
+/*! \brief Get File Descriptor of the stream server
+ *  \param[in] conn Stream Server
+ *  \returns file descriptor or negative on error */
+int
+osmo_stream_srv_get_fd(const struct osmo_stream_srv *conn)
+{
+	switch (conn->mode) {
+	case OSMO_STREAM_MODE_OSMO_FD:
+		return conn->ofd.fd;
+	case OSMO_STREAM_MODE_OSMO_IO:
+		if (conn->iofd)
+			return osmo_iofd_get_fd(conn->iofd);
+	default:
+		break;
+	}
+	return -EINVAL;
+}
+
 /*! \brief Get the master (Link) from a Stream Server
  *  \param[in] conn Stream Server of which we want to know the Link
  *  \returns Link through which the given Stream Server is established */

