xwayland: Only pass Xwayland wl_client to libweston

Remove all handling of process/PID internals from libweston's Xwayland
launcher, and keep this only in the frontend. libweston now only sees
the wl_client and nothing else.

Signed-off-by: Daniel Stone <daniels@collabora.com>

compositor/xwayland.c

@@ -52,7 +52,6 @@ struct wet_xwayland {
 	const struct weston_xwayland_api *api;
 	struct weston_xwayland *xwayland;
 	struct wl_event_source *display_fd_source;
-	struct wl_client *client;
 	int wm_fd;
 	struct wet_process *process;
 };
@@ -82,7 +81,7 @@ handle_display_fd(int fd, uint32_t mask, void *data)
 	if (n <= 0 || (n > 0 && buf[n - 1] != '\n'))
 		return 1;
 
-	wxw->api->xserver_loaded(wxw->xwayland, wxw->client, wxw->wm_fd);
+	wxw->api->xserver_loaded(wxw->xwayland, wxw->wm_fd);
 
 out:
 	wl_event_source_remove(wxw->display_fd_source);
@@ -101,11 +100,10 @@ xserver_cleanup(struct wet_process *process, int status, void *data)
 	assert(process == wxw->process);
 
 	wxw->api->xserver_exited(wxw->xwayland, status);
-	wxw->client = NULL;
 	wxw->process = NULL;
 }
 
-static pid_t
+static struct wl_client *
 spawn_xserver(void *user_data, const char *display, int abstract_fd, int unix_fd)
 {
 	struct wet_xwayland *wxw = user_data;
@@ -117,6 +115,7 @@ spawn_xserver(void *user_data, const char *display, int abstract_fd, int unix_fd
 	char *xserver = NULL;
 	struct weston_config *config = wet_get_config(wxw->compositor);
 	struct weston_config_section *section;
+	struct wl_client *client;
 	struct wl_event_loop *loop;
 	struct custom_env child_env;
 	int no_cloexec_fds[5];
@@ -180,9 +179,9 @@ spawn_xserver(void *user_data, const char *display, int abstract_fd, int unix_fd
 		goto err;
 	}
 
-	wxw->client = wl_client_create(wxw->compositor->wl_display,
+	client = wl_client_create(wxw->compositor->wl_display,
 				  wayland_socket.fds[0]);
-	if (!wxw->client) {
+	if (!client) {
 		weston_log("Couldn't create client for Xwayland\n");
 		goto err_proc;
 	}
@@ -206,7 +205,7 @@ spawn_xserver(void *user_data, const char *display, int abstract_fd, int unix_fd
 
 	free(xserver);
 
-	return wxw->process->pid;
+	return client;
 
 
 err_proc:
@@ -217,7 +216,7 @@ err:
 	fdstr_close_all(&x11_wm_socket);
 	fdstr_close_all(&wayland_socket);
 	free(wxw->process);
-	return -1;
+	return NULL;
 }
 
 static void

include/libweston/xwayland-api.h

@@ -37,10 +37,10 @@ extern "C" {
 struct weston_compositor;
 struct weston_xwayland;
 
-#define WESTON_XWAYLAND_API_NAME "weston_xwayland_v1"
+#define WESTON_XWAYLAND_API_NAME "weston_xwayland_v2"
 #define WESTON_XWAYLAND_SURFACE_API_NAME "weston_xwayland_surface_v1"
 
-typedef pid_t
+typedef struct wl_client *
 (*weston_xwayland_spawn_xserver_func_t)(
 	void *user_data, const char *display, int abstract_fd, int unix_fd);
 
@@ -83,19 +83,16 @@ struct weston_xwayland_api {
 	/** Notify the Xwayland module that the Xwayland server is loaded.
 	 *
 	 * After the Xwayland server process has been spawned it will notify
-	 * the parent that is has finished the initialization by sending a
+	 * the parent that it has finished the initialization by writing to
-	 * SIGUSR1 signal.
+	 * the displayfd passed.
-	 * The caller should listen for that signal and call this function
+	 * The caller should listen for that write and call this function
 	 * when it is received.
 	 *
 	 * \param xwayland The Xwayland context object.
-	 * \param client The wl_client object representing the connection of
-	 *               the Xwayland server process.
 	 * \param wm_fd The file descriptor for the wm.
 	 */
 	void
-	(*xserver_loaded)(struct weston_xwayland *xwayland,
+	(*xserver_loaded)(struct weston_xwayland *xwayland, int wm_fd);
-			  struct wl_client *client, int wm_fd);
 
 	/** Notify the Xwayland module that the Xwayland server has exited.
 	 *

xwayland/launcher.c

@@ -49,13 +49,12 @@ weston_xserver_handle_event(int listen_fd, uint32_t mask, void *data)
 
 	snprintf(display, sizeof display, ":%d", wxs->display);
 
-	wxs->pid = wxs->spawn_func(wxs->user_data, display, wxs->abstract_fd, wxs->unix_fd);
+	wxs->client = wxs->spawn_func(wxs->user_data, display, wxs->abstract_fd, wxs->unix_fd);
-	if (wxs->pid == -1) {
+	if (wxs->client == NULL) {
 		weston_log("Failed to spawn the Xwayland server\n");
 		return 1;
 	}
 
-	weston_log("Spawned Xwayland server, pid %d\n", wxs->pid);
 	wl_event_source_remove(wxs->abstract_source);
 	wl_event_source_remove(wxs->unix_source);
 
@@ -71,7 +70,7 @@ weston_xserver_shutdown(struct weston_xserver *wxs)
 	unlink(path);
 	snprintf(path, sizeof path, "/tmp/.X11-unix/X%d", wxs->display);
 	unlink(path);
-	if (wxs->pid == 0) {
+	if (wxs->client == NULL) {
 		wl_event_source_remove(wxs->abstract_source);
 		wl_event_source_remove(wxs->unix_source);
 	}
@@ -305,12 +304,10 @@ retry:
 }
 
 static void
-weston_xwayland_xserver_loaded(struct weston_xwayland *xwayland,
+weston_xwayland_xserver_loaded(struct weston_xwayland *xwayland, int wm_fd)
-			       struct wl_client *client, int wm_fd)
 {
 	struct weston_xserver *wxs = (struct weston_xserver *)xwayland;
 	wxs->wm = weston_wm_create(wxs, wm_fd);
-	wxs->client = client;
 }
 
 static void
@@ -319,7 +316,6 @@ weston_xwayland_xserver_exited(struct weston_xwayland *xwayland,
 {
 	struct weston_xserver *wxs = (struct weston_xserver *)xwayland;
 
-	wxs->pid = 0;
 	wxs->client = NULL;
 
 	wxs->abstract_source =

xwayland/xwayland.h

@@ -43,7 +43,6 @@ struct weston_xserver {
 	int unix_fd;
 	struct wl_event_source *unix_source;
 	int display;
-	pid_t pid;
 	struct wl_client *client;
 	struct weston_compositor *compositor;
 	struct weston_wm *wm;