[Xcb] Nested XLockDisplay

[Elias Naur]

Hi,

Sorry if this is trivial or have been addressed before, but my
searching failed to bring up anything conclusive. My problem is the
LockDisplay/UnlockDisplay assertion failures in the xlib-on-xcb
library. I've got a LWJGL (http://lwjgl.org) user that complains that
the "xcb_xlib.c:41: xcb_xlib_lock: Assertion `!c->xlib.lock' failed."
occurs with aany test program. This is a java based library, but I
haven't yet tried to find out if the Sun java implementation or the
LWJGL library is at fault. As far as I can tell, the assertion means
that XLockDisplay has been called while the lock was already held.
However, the xlib manual at
http://tronche.com/gui/x/xlib/display/XLockDisplay.html states that
"Nested calls to XLockDisplay() work correctly; the display will not
actually be unlocked until XUnlockDisplay() has been called the same
number of times as XLockDisplay()". Have I misunderstood something or
has the spec changed with xlib-on-xcb to disallow nested XLockDisplay
(I can understand the other common assertion failure that occurs when
XUnlockDisplay is called without holding the lock)?

 - elias