Add protocol debugging facility

connection.c

@@ -563,6 +563,49 @@ wl_closure_invoke(struct wl_closure *closure,
 	ffi_call(&closure->cif, func, &result, closure->args);
 }
 
+void
+wl_closure_print(struct wl_closure *closure, struct wl_object *target)
+{
+	struct wl_object *object;
+	int i;
+
+	fprintf(stderr, "%s(%d).%s(",
+		target->interface->name, target->id,
+		closure->message->name);
+
+	for (i = 2; i < closure->count; i++) {
+		if (i > 2)
+			fprintf(stderr, ", ");
+		switch (closure->message->signature[i - 2]) {
+		case 'u':
+			fprintf(stderr, "%u", closure->values[i].uint32);
+			break;
+		case 'i':
+			fprintf(stderr, "%d", closure->values[i].uint32);
+			break;
+		case 's':
+			fprintf(stderr, "\"%s\"", closure->values[i].string);
+			break;
+		case 'o':
+			object = closure->values[i].object;
+			fprintf(stderr, "object %u", object ? object->id : 0);
+			break;
+		case 'n':
+			fprintf(stderr, "new id %u",
+				closure->values[i].uint32);
+			break;
+		case 'a':
+			fprintf(stderr, "array");
+			break;
+		case 'h':
+			fprintf(stderr, "fd %d", closure->values[i].uint32);
+			break;
+		}
+	}
+
+	fprintf(stderr, ")\n");
+}
+
 void
 wl_closure_destroy(struct wl_closure *closure)
 {

connection.h

@@ -58,6 +58,8 @@ void
 wl_closure_invoke(struct wl_closure *closure,
 		  struct wl_object *target, void (*func)(void), void *data);
 void
+wl_closure_print(struct wl_closure *closure, struct wl_object *target);
+void
 wl_closure_destroy(struct wl_closure *closure);
 
 #endif

wayland-server.c

@@ -73,6 +73,8 @@ struct wl_global {
 
 WL_EXPORT struct wl_surface wl_grab_surface;
 
+static int wl_debug = 0;
+
 WL_EXPORT void
 wl_client_post_event(struct wl_client *client, struct wl_object *sender,
 		     uint32_t opcode, ...)
@@ -149,6 +151,10 @@ wl_client_connection_data(int fd, uint32_t mask, void *data)
 			continue;
 		}
 
+
+		if (wl_debug)
+			wl_closure_print(closure, object);
+
 		wl_closure_invoke(closure, object,
 				  object->implementation[opcode], client);
 
@@ -331,6 +337,11 @@ WL_EXPORT struct wl_display *
 wl_display_create(void)
 {
 	struct wl_display *display;
+	const char *debug;
+
+	debug = getenv("WAYLAND_DEBUG");
+	if (debug)
+		wl_debug = 1;
 
 	display = malloc(sizeof *display);
 	if (display == NULL)