Fix:core:Report errors if graphics or event system is not present.

git-svn-id: http://svn.code.sf.net/p/navit/code/trunk/navit@5996 ffa7fe5e-494d-0410-b361-a75ebd5db220

2 files changed, 27 insertions, 5 deletions

diff --git a/navit/event.c b/navit/event.c
index 550aa7fd..96d2e0dd 100644
--- a/navit/event.c
+++ b/navit/event.c
@@ -29,12 +29,24 @@ static const char *e_system;
 
 static int has_quit;
 
+#define require_method_helper(m)\
+	if(!event_methods.m) {\
+		dbg(lvl_error, "Can't find event system method %s. Event system is %s%s\n",\
+			#m ,e_system?"set to ":"not set.", e_system?e_system:"");\
+
+#define require_method(m)\
+		require_method_helper(m)\
+		return;\
+	}
+
+#define require_method2(m,r)\
+		require_method_helper(m)\
+		return r;\
+	}
+
 void event_main_loop_run(void)
 {
-	if (! event_methods.main_loop_run) {
-		dbg(lvl_error,"no event system set\n");
-		return;
-	}
+	require_method(main_loop_run);
 	event_methods.main_loop_run();
 }
 
@@ -54,42 +66,49 @@ event_main_loop_has_quit(void)
 struct event_watch *
 event_add_watch(int fd, enum event_watch_cond cond, struct callback *cb)
 {
+	require_method2(add_watch, NULL);
 	return event_methods.add_watch(fd, cond, cb);
 }
 
 void
 event_remove_watch(struct event_watch *ev)
 {
+	require_method(remove_watch);
 	event_methods.remove_watch(ev);
 }
 
 struct event_timeout *
 event_add_timeout(int timeout, int multi, struct callback *cb)
 {
+	require_method2(add_timeout, NULL);
 	return event_methods.add_timeout(timeout, multi, cb);
 }
 
 void
 event_remove_timeout(struct event_timeout *ev)
 {
+	require_method(remove_timeout);
 	event_methods.remove_timeout(ev);
 }
 
 struct event_idle *
 event_add_idle(int priority, struct callback *cb)
 {
+	require_method2(add_idle, NULL);
 	return event_methods.add_idle(priority,cb);
 }
 
 void
 event_remove_idle(struct event_idle *ev)
 {
+	require_method(remove_idle);
 	event_methods.remove_idle(ev);
 }
 
 void
 event_call_callback(struct callback_list *cb)
 {
+	require_method(call_callback);
 	event_methods.call_callback(cb);
 }
 
diff --git a/navit/graphics.c b/navit/graphics.c
index 53a1984a..2858de82 100644
--- a/navit/graphics.c
+++ b/navit/graphics.c
@@ -232,12 +232,15 @@ struct graphics * graphics_new(struct attr *parent, struct attr **attrs)
 	struct graphics_priv * (*graphicstype_new)(struct navit *nav, struct graphics_methods *meth, struct attr **attrs, struct callback_list *cbl);
 
         if (! (type_attr=attr_search(attrs, NULL, attr_type))) {
+		dbg(lvl_error,"Graphics plugin type is not set.\n");
                 return NULL;
         }
 
 	graphicstype_new=plugin_get_graphics_type(type_attr->u.str);
-	if (! graphicstype_new)
+	if (! graphicstype_new) {
+		dbg(lvl_error,"Failed to load graphics plugin %s.\n", type_attr->u.str);
 		return NULL;
+	}
 	this_=g_new0(struct graphics, 1);
 	this_->attrs=attr_list_dup(attrs);
 	this_->cbl=callback_list_new();