befc3d22cf
Right now, extension specific pixmap destruction procedures are implemented by wrapping the ScreenRec's DestroyPixmap() proc pointer: the extensions are storing the original pointer in their private data and putting in their own one. On each call, their proc restores the original one, calls it, and switches back again. When multiple extensions doing so, they're forming a kind of daisy chain. (the same is done for lots of other procs) While that approach is looking nice and elegant on the drawing board, it's complicated, dangerous like a chainsaw and makes debugging hard, leading to pretty blurred API borders. It's even getting worse: the proc also has to do ref counting, and only destroy the pixmap if refconter reaching zero - that's all done in the individual screen drivers. Therefore, all extensions must check for refcnt == 1, in order to know when to really act. This commit introduces a simple approach for letting extension hook into the pixmap destruction safely, w/o having to care much about side effects with the call chain. Extensions now can simply register their destructor proc (and an opaque pointer) and get called back - w/o ever having to mess with the ScreenRec's internal structures. Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
X Server
The X server accepts requests from client applications to create windows, which are (normally rectangular) "virtual screens" that the client program can draw into.
Windows are then composed on the actual screen by the X server (or by a separate composite manager) as directed by the window manager, which usually communicates with the user via graphical controls such as buttons and draggable titlebars and borders.
For a comprehensive overview of X Server and X Window System, consult the following article: https://en.wikipedia.org/wiki/X_server
All questions regarding this software should be directed at the Xorg mailing list:
https://lists.freedesktop.org/mailman/listinfo/xorg
The primary development code repository can be found at:
https://gitlab.freedesktop.org/xorg/xserver
For patch submission instructions, see:
https://www.x.org/wiki/Development/Documentation/SubmittingPatches
As with other projects hosted on freedesktop.org, X.Org follows its Code of Conduct, based on the Contributor Covenant. Please conduct yourself in a respectful and civilized manner when using the above mailing lists, bug trackers, etc: