[PATCH wayland v3 6/7] server: Add new API for adding a socket with an existing fd

[Bryce Harrington]

Currently the server can add a socket by name.  To support an embedded
compositor in a Simplified Mandatory Access Control Kernel (Smack)
enabled environment, the embedded compositor should use the socket that
it gets from the system or session compositor.

Signed-off-by: Bryce Harrington <bryce at osg.samsung.com>
Cc: Sung-Jin Park <sj76.park at samsung.com>
Cc: Sangjin Lee <lsj119 at samsung.com>
---
 src/wayland-server-core.h |  3 +++
 src/wayland-server.c      | 46 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 49 insertions(+)

diff --git a/src/wayland-server-core.h b/src/wayland-server-core.h
index 85b4b9e..530053b 100644
--- a/src/wayland-server-core.h
+++ b/src/wayland-server-core.h
@@ -128,6 +128,9 @@ wl_display_get_event_loop(struct wl_display *display);
 int
 wl_display_add_socket(struct wl_display *display, const char *name);
 
+int
+wl_display_add_socket_fd(struct wl_display *display, const char *name, int sock_fd);
+
 const char *
 wl_display_add_socket_auto(struct wl_display *display);
 
diff --git a/src/wayland-server.c b/src/wayland-server.c
index 7c25858..baea832 100644
--- a/src/wayland-server.c
+++ b/src/wayland-server.c
@@ -1201,6 +1201,52 @@ wl_display_add_socket_auto(struct wl_display *display)
 	return NULL;
 }
 
+WL_EXPORT int
+wl_display_add_socket_fd(struct wl_display *display, const char *name, int sock_fd)
+{
+	struct wl_socket *s;
+	struct stat buf;
+
+	/* Require a valid fd or fail */
+	if (sock_fd < 0 || fstat(sock_fd, &buf) < 0 || !S_ISSOCK(buf.st_mode)) {
+		return -1;
+	}
+
+	s = wl_socket_alloc();
+	if (s == NULL)
+		return -1;
+
+	if (name == NULL)
+		name = getenv("WAYLAND_DISPLAY");
+	if (name == NULL)
+		name = "wayland-0";
+
+	if (wl_socket_init_for_display_name(s, name) < 0) {
+		wl_socket_destroy(s);
+		return -1;
+	}
+
+	if (wl_socket_lock(s) < 0) {
+		wl_socket_destroy(s);
+		return -1;
+	}
+
+	/* Reuse the existing fd */
+	s->fd = sock_fd;
+	if (wl_os_set_cloexec_or_close(s->fd) < 0) {
+		wl_log("could not set cloexec on provided fd\n");
+		wl_socket_destroy(s);
+		return -1;
+	}
+
+	if (_wl_display_bind_socket_source(display, s) < 0) {
+		wl_socket_destroy(s);
+		return -1;
+	}
+
+	return 0;
+}
+
 /** Add a socket to Wayland display for the clients to connect.
  *
  * \param display Wayland display to which the socket should be added.
-- 
1.9.1