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nitpicker: Fix implementation of Mode interface 

The generalization of nitpicker's graphic backend changed the interface
of 'Mode::forget', which is a (non-pure) virtual function implemented
by 'User_state::forget'. Unfortunately, the signature change was not
applied to 'User_state::forget' so that the actual implementation was
no longer called. This inconsistency remained unnoticed because there
is a default implementation of the virtual function.

The effect of the omission of the 'User_state::forget' call was a
dangling pointer ('User_state::_pointed_view').

Lesson learned: Always annotate functions with the C++11 'override' when
implementing virtual functions.
This commit is contained in:
Norman Feske 2014-03-19 14:13:47 +01:00 committed by Christian Helmuth
parent 2262eb8347
commit 2f3b67c9e0
4 changed files with 5 additions and 4 deletions
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3
os/src/server/nitpicker/mode.h
View File

@ -15,6 +15,7 @@
#define _MODE_H_
class View;
class Canvas_base;
class Mode
{
@ -53,7 +54,7 @@ class Mode
/**
* Discard all references to specified view
*/
virtual void forget(View const &v) {
virtual void forget(Canvas_base &, View const &v) {
if (&v == _focused_view) _focused_view = 0; }
};

2
os/src/server/nitpicker/user_state.cc
View File

@ -281,7 +281,7 @@ void User_state::handle_event(Input::Event ev, Canvas_base &canvas)
void User_state::forget(Canvas_base &canvas, View const &view)
{
if (focused_view() == &view) {
Mode::forget(view);
Mode::forget(canvas, view);
_menubar.state(Menubar_state(*this, "", "", BLACK));
update_all_views(canvas);
}

2
os/src/server/nitpicker/user_state.h
View File

@ -89,7 +89,7 @@ class User_state : public Mode, public View_stack
/**
* Mode interface
*/
void forget(Canvas_base &, View const &);
void forget(Canvas_base &, View const &) override;
};
#endif

2
os/src/server/nitpicker/view_stack.cc
View File

@ -315,7 +315,7 @@ void View_stack::remove_view(Canvas_base &canvas, View const &view, bool redraw)
* the current one, resulting in a dangling pointer right after the view
* gets destructed by the caller of 'removed_view'.
*/
_mode.forget(view);
_mode.forget(canvas, view);
/* redraw area where the view was visible */
if (redraw)