bbda345a71
If any flags are specified in a call to xcb_take_socket,
they should only be applied to replies for requests sent
after that function returns (and until the socket is
re-acquired by XCB).
Previously, they would also be incorrectly applied to the
reply for the last request sent before the socket was taken.
For instance, in this example program the reply for the
GetInputFocus request gets discarded, even though it was
sent before the socket was taken. This results in the
call to retrieve the reply hanging indefinitely.
static void return_socket(void *closure) {}
int main(void)
{
Display *dpy = XOpenDisplay(NULL);
xcb_connection_t *c = XGetXCBConnection(dpy);
xcb_get_input_focus_cookie_t cookie = xcb_get_input_focus_unchecked(c);
xcb_flush(c);
uint64_t seq;
xcb_take_socket(c, return_socket, dpy, XCB_REQUEST_DISCARD_REPLY, &seq);
xcb_generic_error_t *err;
xcb_get_input_focus_reply(c, cookie, &err);
}
In practice, this has been causing intermittent KWin crashes when
used in combination with the proprietary NVIDIA driver such as
https://bugs.kde.org/show_bug.cgi?id=386370 since when Xlib fails to
retrieve one of these incorrectly discarded replies it triggers
an IO error.
Signed-off-by: Erik Kurzinger <ekurzinger@nvidia.com>
Signed-off-by: Uli Schlachter <psychon@znc.in>
|
||
|---|---|---|
| doc | ||
| m4 | ||
| man | ||
| src | ||
| tests | ||
| tools | ||
| .autom4te.cfg | ||
| .gitignore | ||
| COPYING | ||
| Makefile.am | ||
| NEWS | ||
| README | ||
| autogen.sh | ||
| check-pc-requires | ||
| configure.ac | ||
| xcb-composite.pc.in | ||
| xcb-damage.pc.in | ||
| xcb-dpms.pc.in | ||
| xcb-dri2.pc.in | ||
| xcb-dri3.pc.in | ||
| xcb-ge.pc.in | ||
| xcb-glx.pc.in | ||
| xcb-present.pc.in | ||
| xcb-randr.pc.in | ||
| xcb-record.pc.in | ||
| xcb-render.pc.in | ||
| xcb-res.pc.in | ||
| xcb-screensaver.pc.in | ||
| xcb-shape.pc.in | ||
| xcb-shm.pc.in | ||
| xcb-sync.pc.in | ||
| xcb-xevie.pc.in | ||
| xcb-xf86dri.pc.in | ||
| xcb-xfixes.pc.in | ||
| xcb-xinerama.pc.in | ||
| xcb-xinput.pc.in | ||
| xcb-xkb.pc.in | ||
| xcb-xprint.pc.in | ||
| xcb-xselinux.pc.in | ||
| xcb-xtest.pc.in | ||
| xcb-xv.pc.in | ||
| xcb-xvmc.pc.in | ||
| xcb.pc.in | ||
About libxcb
============
libxcb provides an interface to the X Window System protocol, which
replaces the current Xlib interface. It has several advantages over
Xlib, including:
- size: small, simple library, and lower memory footprint
- latency hiding: batch several requests and wait for the replies later
- direct protocol access: interface and protocol correspond exactly
- proven thread support: transparently access XCB from multiple threads
- easy extension implementation: interfaces auto-generated from XML-XCB
Xlib can also use XCB as a transport layer, allowing software to make
requests and receive responses with both, which eases porting to XCB.
However, client programs, libraries, and toolkits will gain the most
benefit from a native XCB port.
Please report any issues you find to the freedesktop.org bug tracker,
at:
<https://bugs.freedesktop.org/enter_bug.cgi?product=XCB>
Discussion about XCB occurs on the XCB mailing list:
<mailto:xcb at lists.freedesktop.org>
<http://lists.freedesktop.org/mailman/listinfo/xcb>
You can obtain the latest development versions of XCB using GIT.
For anonymous checkouts, use:
git clone git://anongit.freedesktop.org/git/xcb/libxcb
For developers, use:
git clone git+ssh://git.freedesktop.org/git/xcb/libxcb