Add support for running with a primary client

On startup weston now detects the WAYLAND_SERVER_SOCKET environment
variable.  If found, weston does not create the display like normal, but
instead directly adds a client corresponding to the given fd.  This,
combined with the fullscreen shell, allows a process to spawn weston and
use it as a backend.

Signed-off-by: Jason Ekstrand <jason@jlekstrand.net>

diff --git a/src/compositor.c b/src/compositor.c
index 362e959..c293218 100644 (file)
--- a/src/compositor.c
+++ b/src/compositor.c
@@ -4080,6 +4080,16 @@ catch_signals(void)
        sigaction(SIGABRT, &action, NULL);
 }
 
+static void
+handle_primary_client_destroyed(struct wl_listener *listener, void *data)
+{
+       struct wl_client *client = data;
+
+       weston_log("Primary client died.  Closing...\n");
+
+       wl_display_terminate(wl_client_get_display(client));
+}
+
 int main(int argc, char *argv[])
 {
        int ret = EXIT_SUCCESS;
@@ -4091,19 +4101,22 @@ int main(int argc, char *argv[])
                *(*backend_init)(struct wl_display *display,
                                 int *argc, char *argv[],
                                 struct weston_config *config);
-       int i;
+       int i, fd;
        char *backend = NULL;
        char *option_backend = NULL;
        char *shell = NULL;
        char *option_shell = NULL;
        char *modules, *option_modules = NULL;
        char *log = NULL;
+       char *server_socket = NULL, *end;
        int32_t idle_time = 300;
        int32_t help = 0;
        char *socket_name = "wayland-0";
        int32_t version = 0;
        struct weston_config *config;
        struct weston_config_section *section;
+       struct wl_client *primary_client;
+       struct wl_listener primary_client_destroyed;
 
        const struct weston_option core_options[] = {
                { WESTON_OPTION_STRING, "backend", 'B', &option_backend },
@@ -4226,10 +4239,33 @@ int main(int argc, char *argv[])
 
        weston_compositor_log_capabilities(ec);
 
-       if (wl_display_add_socket(display, socket_name)) {
-               weston_log("fatal: failed to add socket: %m\n");
-               ret = EXIT_FAILURE;
-               goto out;
+       server_socket = getenv("WAYLAND_SERVER_SOCKET");
+       if (server_socket) {
+               weston_log("Running with single client\n");
+               fd = strtol(server_socket, &end, 0);
+               if (*end != '\0')
+                       fd = -1;
+       } else {
+               fd = -1;
+       }
+
+       if (fd != -1) {
+               primary_client = wl_client_create(display, fd);
+               if (!primary_client) {
+                       weston_log("fatal: failed to add client: %m\n");
+                       ret = EXIT_FAILURE;
+                       goto out;
+               }
+               primary_client_destroyed.notify =
+                       handle_primary_client_destroyed;
+               wl_client_add_destroy_listener(primary_client,
+                                              &primary_client_destroyed);
+       } else {
+               if (wl_display_add_socket(display, socket_name)) {
+                       weston_log("fatal: failed to add socket: %m\n");
+                       ret = EXIT_FAILURE;
+                       goto out;
+               }
        }
 
        weston_compositor_wake(ec);