On Nov 11 2022, Matthieu Herrb wrote:
> On Fri, Nov 11, 2022 at 03:17:21PM +0100, Walter Alejandro Iglesias wrote:
> > On Nov 11 2022, Matthieu Herrb wrote:
> > > Hi,
> > >
> > > So the patch provided by Adam Jackson upstreams is completely buggy.
> > >
> > > - the logic to setup the new locking function was busted
> > > - I've observed cases where even the XGetIfEvent() function gets
> > > re-rentered. So the flags does in fact need to be a counter.
> > >
> > > New patch which works for me with fvwm2...
> > >
> > > Testing is welcome...
> >
> > Unfortunately I still can reproduce the bug.
> >
> > This patch also makes firefox crash, (I'm not sure if it's because of
> > firefox or cwm). After reinstalling xenocara from the snapshots
> > packages I could run firefox again.
> >
> > fvwm is giving a lot of problems lately, there's also this drm bug I
> > reported:
> >
> > https://marc.info/?l=openbsd-bugs&m=166332904632232&w=2
> >
> > Now FvwmIcons is crashing on fvwm3... I'm giving up with fvwm, I'm more
> > comfortable with cwm.
>
> Ok, I've figured out the cwm + firefox issue. There's also a
> XInternalLock that needs to be neutered in the X*IfEvent() callbacks.
>
> New diff, on which I've left my debug printfs. If you get other
> crashes it may be interesting to look in .xsession-errors...
This patch solved the firefox cwm issue. Firefox shows this when
it starts:
~$ firefox
XXX _XLockDisplay 1
XXX _XIfEventInternalLockDisplay 1
XXX _XIfEventUnlockDisplay 0
fvwm2/3 still crashing.
>
> Index: Makefile.bsd-wrapper
> ===================================================================
> RCS file: /cvs/OpenBSD/xenocara/lib/libX11/Makefile.bsd-wrapper,v
> retrieving revision 1.29
> diff -u -p -u -r1.29 Makefile.bsd-wrapper
> --- Makefile.bsd-wrapper 3 Sep 2022 06:55:25 -0000 1.29
> +++ Makefile.bsd-wrapper 11 Nov 2022 15:13:59 -0000
> @@ -14,7 +14,6 @@ SHARED_LIBS= X11 18.0 X11_xcb 2.0
>
> CONFIGURE_ARGS= --enable-tcp-transport --enable-unix-transport --enable-ipv6
> \
> --disable-composecache \
> - --disable-thread-safety-constructor \
> --without-xmlto --without-fop --without-xsltproc
>
> .include <bsd.xorg.mk>
> Index: include/X11/Xlibint.h
> ===================================================================
> RCS file: /cvs/OpenBSD/xenocara/lib/libX11/include/X11/Xlibint.h,v
> retrieving revision 1.15
> diff -u -p -u -r1.15 Xlibint.h
> --- include/X11/Xlibint.h 21 Feb 2022 08:01:24 -0000 1.15
> +++ include/X11/Xlibint.h 11 Nov 2022 15:14:00 -0000
> @@ -207,6 +207,7 @@ struct _XDisplay
>
> XIOErrorExitHandler exit_handler;
> void *exit_handler_data;
> + CARD32 in_ifevent;
> };
>
> #define XAllocIDs(dpy,ids,n) (*(dpy)->idlist_alloc)(dpy,ids,n)
> Index: src/ChkIfEv.c
> ===================================================================
> RCS file: /cvs/OpenBSD/xenocara/lib/libX11/src/ChkIfEv.c,v
> retrieving revision 1.4
> diff -u -p -u -r1.4 ChkIfEv.c
> --- src/ChkIfEv.c 30 May 2011 19:19:38 -0000 1.4
> +++ src/ChkIfEv.c 11 Nov 2022 15:14:00 -0000
> @@ -49,6 +49,7 @@ Bool XCheckIfEvent (
> unsigned long qe_serial = 0;
> int n; /* time through count */
>
> + dpy->in_ifevent++;
> LockDisplay(dpy);
> prev = NULL;
> for (n = 3; --n >= 0;) {
> @@ -60,6 +61,7 @@ Bool XCheckIfEvent (
> *event = qelt->event;
> _XDeq(dpy, prev, qelt);
> _XStoreEventCookie(dpy, event);
> + dpy->in_ifevent = False;
> UnlockDisplay(dpy);
> return True;
> }
> @@ -78,6 +80,7 @@ Bool XCheckIfEvent (
> /* another thread has snatched this event */
> prev = NULL;
> }
> + dpy->in_ifevent--;
> UnlockDisplay(dpy);
> return False;
> }
> Index: src/IfEvent.c
> ===================================================================
> RCS file: /cvs/OpenBSD/xenocara/lib/libX11/src/IfEvent.c,v
> retrieving revision 1.4
> diff -u -p -u -r1.4 IfEvent.c
> --- src/IfEvent.c 30 May 2011 19:19:38 -0000 1.4
> +++ src/IfEvent.c 11 Nov 2022 15:14:00 -0000
> @@ -48,6 +48,7 @@ XIfEvent (
> register _XQEvent *qelt, *prev;
> unsigned long qe_serial = 0;
>
> + dpy->in_ifevent++;
> LockDisplay(dpy);
> prev = NULL;
> while (1) {
> @@ -59,6 +60,7 @@ XIfEvent (
> *event = qelt->event;
> _XDeq(dpy, prev, qelt);
> _XStoreEventCookie(dpy, event);
> + dpy->in_ifevent--;
> UnlockDisplay(dpy);
> return 0;
> }
> Index: src/OpenDis.c
> ===================================================================
> RCS file: /cvs/OpenBSD/xenocara/lib/libX11/src/OpenDis.c,v
> retrieving revision 1.12
> diff -u -p -u -r1.12 OpenDis.c
> --- src/OpenDis.c 28 Nov 2020 14:39:48 -0000 1.12
> +++ src/OpenDis.c 11 Nov 2022 15:14:00 -0000
> @@ -189,6 +189,7 @@ XOpenDisplay (
> dpy->xcmisc_opcode = 0;
> dpy->xkb_info = NULL;
> dpy->exit_handler_data = NULL;
> + dpy->in_ifevent = 0;
>
> /*
> * Setup other information in this display structure.
> Index: src/PeekIfEv.c
> ===================================================================
> RCS file: /cvs/OpenBSD/xenocara/lib/libX11/src/PeekIfEv.c,v
> retrieving revision 1.3
> diff -u -p -u -r1.3 PeekIfEv.c
> --- src/PeekIfEv.c 30 May 2011 19:19:38 -0000 1.3
> +++ src/PeekIfEv.c 11 Nov 2022 15:14:00 -0000
> @@ -49,6 +49,7 @@ XPeekIfEvent (
> register _XQEvent *prev, *qelt;
> unsigned long qe_serial = 0;
>
> + dpy->in_ifevent++;
> LockDisplay(dpy);
> prev = NULL;
> while (1) {
> @@ -63,6 +64,7 @@ XPeekIfEvent (
> _XStoreEventCookie(dpy, ©);
> *event = copy;
> }
> + dpy->in_ifevent--;
> UnlockDisplay(dpy);
> return 0;
> }
> Index: src/locking.c
> ===================================================================
> RCS file: /cvs/OpenBSD/xenocara/lib/libX11/src/locking.c,v
> retrieving revision 1.8
> diff -u -p -u -r1.8 locking.c
> --- src/locking.c 28 Nov 2020 14:39:48 -0000 1.8
> +++ src/locking.c 11 Nov 2022 15:14:00 -0000
> @@ -40,6 +40,7 @@ in this Software without prior written a
> #undef _XFreeMutex
>
> #ifdef XTHREADS
> +#include <stdio.h>
>
> #ifdef __UNIXWARE__
> #include <dlfcn.h>
> @@ -455,6 +456,51 @@ static void _XDisplayLockWait(
> static void _XLockDisplay(
> Display *dpy
> XTHREADS_FILE_LINE_ARGS
> + );
> +
> +static void _XIfEventLockDisplay(
> + Display *dpy
> + XTHREADS_FILE_LINE_ARGS
> + )
> +{
> + printf("XXX %s %d\n", __func__, dpy->in_ifevent);
> + /* assert(dpy->in_ifevent); */
> +}
> +
> +static void _XInternalLockDisplay(
> + Display *dpy,
> + Bool wskip
> + XTHREADS_FILE_LINE_ARGS
> + );
> +
> +static void _XIfEventInternalLockDisplay(
> + Display *dpy,
> + Bool wskip
> + XTHREADS_FILE_LINE_ARGS
> + )
> +{
> + printf("XXX %s %d\n", __func__, dpy->in_ifevent);
> +}
> +
> +static void _XIfEventUnlockDisplay(
> + Display *dpy
> + XTHREADS_FILE_LINE_ARGS
> + )
> +{
> + setbuf(stdout, NULL);
> + if (dpy->in_ifevent == 0) {
> + printf("XXX %s %d\n", __func__, dpy->in_ifevent);
> + dpy->lock_fns->lock_display = _XLockDisplay;
> + dpy->lock_fns->unlock_display = _XUnlockDisplay;
> + dpy->lock->internal_lock_display = _XInternalLockDisplay;
> + UnlockDisplay(dpy);
> + } else
> + return;
> +}
> +
> +static void _XLockDisplay(
> + Display *dpy
> + XTHREADS_FILE_LINE_ARGS
> )
> {
> #ifdef XTHREADS
> @@ -478,6 +524,12 @@ static void _XLockDisplay(
> #endif
> _XIDHandler(dpy);
> _XSeqSyncFunction(dpy);
> + if (dpy->in_ifevent) {
> + printf("XXX %s %d\n", __func__, dpy->in_ifevent);
> + dpy->lock_fns->lock_display = _XIfEventLockDisplay;
> + dpy->lock_fns->unlock_display = _XIfEventUnlockDisplay;
> + dpy->lock->internal_lock_display = _XIfEventInternalLockDisplay;
> + }
> }
>
> /*
>
> --
> Matthieu Herrb
--
Walter
