Running gnome-shell under valgrind, I saw the attached invalid write.
Basically we can destroy a window during event processing, and the old
window_remove_filters simply called g_free() on the filter, ignoring
the refcount. Then later in event processing we call filter->refcount--,
which is writing to free()d memory.
Fix this by centralizing list mutation and refcount handling inside
a new shared _gdk_window_filter_unref() function, and using that
everywhere.
==13876== Invalid write of size 4
==13876== at 0x446B181: gdk_event_apply_filters (gdkeventsource.c:86)
==13876== by 0x446B411: _gdk_events_queue (gdkeventsource.c:188)
==13876== by 0x44437EF: gdk_display_get_event (gdkdisplay.c:410)
==13876== by 0x446B009: gdk_event_source_dispatch (gdkeventsource.c:317)
==13876== by 0x4AB7159: g_main_context_dispatch (gmain.c:2436)
==13876== by 0x4AB7957: g_main_context_iterate.clone.5 (gmain.c:3087)
==13876== by 0x4AB806A: g_main_loop_run (gmain.c:3295)
==13876== by 0x8084D6B: main (main.c:722)
==13876== Address 0x1658bcac is 12 bytes inside a block of size 16 free'd
==13876== at 0x4005EAD: free (vg_replace_malloc.c:366)
==13876== by 0x4ABE515: g_free (gmem.c:263)
==13876== by 0x444BCC9: window_remove_filters (gdkwindow.c:1873)
==13876== by 0x4454BA3: _gdk_window_destroy_hierarchy (gdkwindow.c:2043)
==13876== by 0x447BF6E: gdk_window_destroy_notify (gdkwindow-x11.c:1115)
==13876== by 0x43588E2: _gtk_socket_windowing_filter_func (gtksocket-x11.c:518)
==13876== by 0x446B170: gdk_event_apply_filters (gdkeventsource.c:79)
==13876== by 0x446B411: _gdk_events_queue (gdkeventsource.c:188)
==13876== by 0x44437EF: gdk_display_get_event (gdkdisplay.c:410)
==13876== by 0x446B009: gdk_event_source_dispatch (gdkeventsource.c:317)
==13876== by 0x4AB7159: g_main_context_dispatch (gmain.c:2436)
==13876== by 0x4AB7957: g_main_context_iterate.clone.5 (gmain.c:3087)
https://bugzilla.gnome.org/show_bug.cgi?id=637464
The old functions to get core pointer and devices list are gone as
well. This slice is entirely replaced internally by multidevice
handling and may just go.
When setting no shape on an unshaped window, nothing changes,
so return early instead of recomputing lots of visibility
information.
Pointed out by Owen Taylor in bug 637156.
This function will enable events for all devices of a given
GdkInputSource, either these available at the time of the call,
or these that are connected in the future.
This function may be used to know the hardware device that triggered
an event, it could resort to the master device in the few cases there's
not a direct hardware device to relate to the event (i.e.: crossing events
due to grabs)
One less magic function. Also refactored it to make it easier to
implement. It now returns TRUE if it beeped and FALSE if it failed to do
so. A default implementation exists that just returns FALSE for all the
backends that can't beep windows (read: everything but X11 with XKB -
and why on earth do keyboard libs implement beeping?)
Trying to get rid of all the _gdk_windowing_something() functions that
we expect backends to magically know about and instead put them in a
proper interface (mostly GdkWindowImplClass).
... instead of _gdk_drawable_ref_cairo_surface() where appropriate.
Also, don't implement the drawable->create_cairo_surface vfunc anymore.
This is in preparation for the split of GdkWindow from GdkDrawable.
You are not allowed to track surfaces from GDK or draw outside of expose
events. So we can remove ugly hacks needed previously. See
https://bugzilla.gnome.org/show_bug.cgi?id=606009 for the introduction
of this workaround.
This is not strictly an API change as GdkDrawable is typedeffed to
GdkWindow, but it changes the header, so I'm marking it as such.
gdk_cairo_create() can only be used with windows these days, so it makes
sense to pass a window. With that, we can alseo remove the
set_cairo_clip() vfunc from GdkDrawable and implement it inside
gdkwindow.c.
An event filter may add or remove filters itself. This patch does
two things to address this case. The first is to take a temporary
reference to the filter while it is being used. The second is
to wait until after the filter function is run before determining
the next node in the list to process. This guards against
changes to the next node. It also does not run functions
that have been marked as removed. Though I'm not sure if this
case can arise.
https://bugzilla.gnome.org/show_bug.cgi?id=635380
This new function takes a GdkRGBA in order to set the background to
an alpha color. Keep in mind that RGBA visuals and a composited environment
are still necessary to have an alpha background displayed.
Add signal GdkWindow::create-surface which allows to use any
surface type as storage for offscreen windows.
Test the new signal in tests/gdkoffscreenbox.c
This previously caused the x11 code to do a XSetWindowBackgroundPixmap
call on a window that was about to be destroyed. And that's not really
useful.
https://bugzilla.gnome.org/show_bug.cgi?id=630864
The feature can and should be implemented manually using
gdk_window_get_background() and Cairo drawing. A non-cairo drawing API
does not make sense in GDK anymore.
Now that we don't create pixmaps anymore, this function is not needed
anymore. The indirection it did previously is now basically moved to
gdk_window_create_similar_surface()
With Cairo 1.10 now having cairo_surface_create_for_rectangle(), we can
use them. No need to create multiple native surfaces for the same X
window (ugh) anymore.
The notion of a source drawable does not make a lot of sense for windows
that are not backed by a drawable, such as GdkOffscreenWindow after
converting it to cairo_surface_t.
Now the window background is a cairo_pattern_t. The backends will try to
set this as good as they can on the windowing system, but no guarantees
are made on wether the windowing system supports the pattern.
Also gets rid of GDK_NO_BG as undefined behavior is not a good idea to
support, and GDK_NO_BG effectively made the window's contents undefined.
It wasn't effectively used in GTK anyway.
This removes gdk_window_shape_combine_mask() and
gdk_window_input_shape_combine_mask(). GdkBitmap is going away and a
replacement exists via the combine_region() functions and
gdk_cairo_region_create_from_surface().
They were added as accessors for 2.22 even though querying the
background wasn't possible previously. As GTK 3.0 will change background
handling, it doesn't make sense at all to expose these getters.
For windows with alpha channel, the previous contents would otherwise
not be erased. Visible for example in the status icon code.
Thanks to Thomas Wood for noticing.
While X11 surfaces can be resized, this is not the case for Quartz
surfaces. Instead of resizing we will invalidate the surface instead.
By giving _gdk_windowing_set_cairo_surface_size() a boolean return
value, we can signal back whether or not resizing was possible. If not
possible, we invalidate the surface.
