libweston: Decouple weston_debug_compositor from weston_compositor

This patch allows initialization of weston-debug/log framework much earlier
than weston_compositor, which in turn will provide the option start
logging before weston_compositor has been created.

Signed-off-by: Marius Vlad <marius.vlad@collabora.com>

compositor/main.c

@@ -2918,6 +2918,7 @@ int main(int argc, char *argv[])
 	struct wl_listener primary_client_destroyed;
 	struct weston_seat *seat;
 	struct wet_compositor wet = { 0 };
+	struct weston_debug_compositor *wdc = NULL;
 	int require_input;
 	sigset_t mask;
 
@@ -2961,6 +2962,12 @@ int main(int argc, char *argv[])
 		return EXIT_SUCCESS;
 	}
 
+	wdc = weston_debug_compositor_create();
+	if (!wdc) {
+		fprintf(stderr, "Failed to initialize weston debug framework.\n");
+		return EXIT_FAILURE;
+	}
+
 	weston_log_set_handler(vlog, vlog_continue);
 	weston_log_file_open(log);
 
@@ -3025,7 +3032,7 @@ int main(int argc, char *argv[])
 			backend = weston_choose_default_backend();
 	}
 
-	wet.compositor = weston_compositor_create(display, &wet);
+	wet.compositor = weston_compositor_create(display, wdc, &wet);
 	if (wet.compositor == NULL) {
 		weston_log("fatal: failed to create compositor\n");
 		goto out;

include/libweston/libweston.h

@@ -1982,7 +1982,8 @@ weston_compositor_print_scene_graph(struct weston_compositor *ec);
 void
 weston_compositor_destroy(struct weston_compositor *ec);
 struct weston_compositor *
-weston_compositor_create(struct wl_display *display, void *user_data);
+weston_compositor_create(struct wl_display *display,
+			 struct weston_debug_compositor *wdc, void *user_data);
 
 enum weston_compositor_backend {
 	WESTON_BACKEND_DRM,
@@ -2376,8 +2377,12 @@ int
 weston_compositor_enable_touch_calibrator(struct weston_compositor *compositor,
 				weston_touch_calibration_save_func save);
 
+struct weston_debug_compositor *
+weston_debug_compositor_create(void);
+
 int
-weston_debug_compositor_create(struct weston_compositor *compositor);
+weston_debug_compositor_setup(struct weston_compositor *compositor,
+			      struct weston_debug_compositor *wdc);
 
 void
 weston_debug_compositor_destroy(struct weston_compositor *compositor);

libweston/compositor.c

@@ -6782,11 +6782,14 @@ debug_scene_graph_cb(struct weston_debug_stream *stream, void *data)
  *
  * \param display The Wayland display to be used.
  * \param user_data A pointer to an object that can later be retrieved
+ * \param wdc A pointer to weston_debug_compositor
  * using the \ref weston_compositor_get_user_data function.
  * \return The compositor instance on success or NULL on failure.
  */
 WL_EXPORT struct weston_compositor *
-weston_compositor_create(struct wl_display *display, void *user_data)
+weston_compositor_create(struct wl_display *display,
+			 struct weston_debug_compositor *wdc,
+			 void *user_data)
 {
 	struct weston_compositor *ec;
 	struct wl_event_loop *loop;
@@ -6840,7 +6843,7 @@ weston_compositor_create(struct wl_display *display, void *user_data)
 			      ec, bind_presentation))
 		goto fail;
 
-	if (weston_debug_compositor_create(ec) < 0)
+	if (weston_debug_compositor_setup(ec, wdc) < 0)
 		goto fail;
 
 	if (weston_input_init(ec) != 0)

libweston/weston-debug.c

@@ -253,6 +253,28 @@ bind_weston_debug(struct wl_client *client,
        }
 }
 
+/**
+ * Connect weston-compositor structure to weston-debug structure
+ * an vice versa.
+ *
+ * \param compositor
+ * \param wdc
+ * \return 0 on success, -1 on failure
+ *
+ */
+int
+weston_debug_compositor_setup(struct weston_compositor *compositor,
+			      struct weston_debug_compositor *wdc)
+{
+	if (compositor->weston_debug)
+		return -1;
+
+	wdc->compositor = compositor;
+	compositor->weston_debug = wdc;
+
+	return 0;
+}
+
 /** Initialize weston-debug structure
  *
  * \param compositor The libweston compositor.
@@ -264,24 +286,18 @@ bind_weston_debug(struct wl_client *client,
  *
  * \internal
  */
-int
-weston_debug_compositor_create(struct weston_compositor *compositor)
+WL_EXPORT struct weston_debug_compositor *
+weston_debug_compositor_create(void)
 {
 	struct weston_debug_compositor *wdc;
 
-	if (compositor->weston_debug)
-		return -1;
-
 	wdc = zalloc(sizeof *wdc);
 	if (!wdc)
-		return -1;
+		return NULL;
 
-	wdc->compositor = compositor;
 	wl_list_init(&wdc->scope_list);
 
-	compositor->weston_debug = wdc;
-
-	return 0;
+	return wdc;
 }
 
 /** Destroy weston_debug_compositor structure