Original keychord patch by Hai Nguyen <hhai2105@gmail.com>, updated for
dwm 6.4+ grabkeys() by Aaron Zueger <contact@azureorange.xyz>. This
revision rebases onto dwm 6.8 and fixes an event-loss bug in the chord
wait loop.
The wait loop used to discard every event that was not a KeyPress:
while (running && !XNextEvent(dpy, &event) && !ran)
if(event.type == KeyPress)
break;
Two consequences, both reproduced on Xephyr:
1. Unrecoverable input freeze. grabbuttons() grabs unfocused clients
GrabModeSync/GrabModeSync, so clicking one freezes pointer AND
keyboard until the grabbing client calls XAllowEvents. dwm does that
in buttonpress() -- but if the ButtonPress is discarded here,
buttonpress() never runs. The grab stays frozen forever and the loop
can never exit, because a frozen keyboard cannot deliver the KeyPress
it is waiting for. Only killing dwm ends it; XSendEvent is discarded
by this same loop and XTEST queues behind the frozen device.
Repro: press a chord prefix, then click any unfocused client.
Observed: XGrabKeyboard -> GrabFrozen, XQueryPointer -> Button1 held.
2. Orphaned windows. A MapRequest arriving mid-chord is dropped, so a
window opening during a chord is never managed. DestroyNotify,
Expose and ConfigureRequest are lost the same way.
Dispatch through handler[] as run() does, breaking on KeyPress before
dispatch so keypress() cannot recurse. The `&& !ran` term is dropped:
ran is always 0 on entry and nothing in the body can set it.
By default, when dwm is recompiled-restarted all clients will
lose it's current tag and collapse to first tag. This patch preserves
clients on old tags, however note that layout order is not preserved.
Lukasz Kasprzak