The video pool can be accessed with the display lock held, for example,
when releasing a buffer from inside vaapisink_render, but allocating
a new object can may also take the display lock. Which means a possible
deadlock.
https://bugzilla.gnome.org/show_bug.cgi?id=747944
The queue of free objects to used was deallocated with g_queue_free_full().
However, this convenience function shall only be used if the original queue
was allocated with g_queue_new(). This caused memory corruption, eventually
leading to a crash.
The correct solution is to pair the g_queue_init() with the corresponding
g_queue_clear(), while iterating over all free objects to deallocate them.
Drop obsolete GST_VAAPI_IS_xxx() helper macros since we are no longer
deriving from GObject and so those were only checking for whether the
argument was NULL or not. This is now irrelevant, and even confusing
to some extent, because we no longer have type checking.
Note: this incurs more type checking (review) but the libgstvaapi is
rather small, so this is manageable.
Port GstVaapiVideoPool, GstVaapiSurfacePool and GstVaapiImagePool to
GstVaapiMiniObject. Drop gst_vaapi_video_pool_get_caps() since it was
no longer used for a long time. Make object allocators static, i.e.
local to the shared library.
This is a preferred thread-safe version. Also add an inline version of
g_clear_object() if compiling with glib < 2.28.
Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>
