Commit 60527106 authored by Keith Packard's avatar Keith Packard

xkb: merge lockedPtrButtons state from all attached SDs.

Problem:
lockedPtrButtons keeps the state of the buttons locked by a PointerKeys button
press. Unconditionally clearing the bits may cause stuck buttons in this
sequence of events:

1. type Shift + NumLock to enable PointerKeys
2. type 0/Ins on keypad to emulate Button 1 press
        → button1 press event to client
3. press and release button 1 on physical mouse
        → button1 release event to client

Button 1 on the MD is now stuck and cannot be released.

Cause:
XKB PointerKeys button events are posted through the XTEST pointer device.
Once a press is generated, the XTEST device's button is down. The DIX merges
the button state of all attached SDs, hence the MD will have a button down
while the XTEST device has a button down.

PointerKey button events are only generated on the master device to avoid
duplicate events (see XkbFakeDeviceButton()). If the MD has the
lockedPtrButtons bit cleared by a release event on a physical device, no
such event is generated when a keyboard device triggers the PointerKey
ButtonRelease trigger. Since the event - if generated - is posted through
the XTEST pointer device, lack of a generated ButtonRelease event on the
XTEST pointer device means the button is never released, resulting in the
stuck button observed above.

Solution:
This patch merges the MD's lockedPtrButtons with the one of all attached
slave devices on release events. Thus, as long as one attached keyboard has
a lockedPtrButtons bit set, this bit is kept in the MD. Once a PointerKey
button is released on all keyboards, the matching release event is emulated
from the MD through the XTEST pointer device, thus also releasing the button
in the DIX.
Signed-off-by: Peter Hutterer's avatarPeter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Keith Packard's avatarKeith Packard <keithp@keithp.com>
Signed-off-by: Keith Packard's avatarKeith Packard <keithp@keithp.com>
parent 28e33ae6
......@@ -924,6 +924,9 @@ extern int XkbGetEffectiveGroup(
XkbStatePtr /* xkbstate */,
CARD8 /* keycode */);
extern void XkbMergeLockedPtrBtns(
DeviceIntPtr /* master */);
#include "xkbfile.h"
#include "xkbrules.h"
......
......@@ -707,8 +707,24 @@ DeviceEvent *event = &ev->device_event;
changed |= XkbPointerButtonMask;
}
else if (event->type == ET_ButtonRelease) {
if (xkbi)
if (xkbi) {
xkbi->lockedPtrButtons&= ~(1 << (event->detail.key & 0x7));
/* Merge this MD's lockedPtrButtons with the one of all
* attached slave devices.
* The DIX uses a merged button state for MDs, not
* releasing buttons until the last SD has released
* thenm. If we unconditionally clear the
* lockedPtrButtons bit on the MD, a PointerKeys button
* release on the SD keyboard won't generate the required fake button
* event on the XTEST pointer, thus never processing the
* button event in the DIX and the XTEST pointer's
* buttons stay down - result is a stuck button.
*/
if (IsMaster(dev))
XkbMergeLockedPtrBtns(dev);
}
changed |= XkbPointerButtonMask;
}
......
......@@ -633,6 +633,16 @@ _XkbFilterPointerBtn( XkbSrvInfoPtr xkbi,
break;
}
xkbi->lockedPtrButtons&= ~(1<<button);
if (IsMaster(xkbi->device))
{
XkbMergeLockedPtrBtns(xkbi->device);
/* One SD still has lock set, don't post event */
if ((xkbi->lockedPtrButtons & (1 << button)) != 0)
break;
}
/* fallthrough */
case XkbSA_PtrBtn:
XkbFakeDeviceButton(xkbi->device, 0, button);
break;
......
......@@ -2094,3 +2094,29 @@ XkbGetEffectiveGroup(XkbSrvInfoPtr xkbi, XkbStatePtr xkbState, CARD8 keycode)
return effectiveGroup;
}
/* Merge the lockedPtrButtons from all attached SDs for the given master
* device into the MD's state.
*/
void
XkbMergeLockedPtrBtns(DeviceIntPtr master)
{
DeviceIntPtr d = inputInfo.devices;
XkbSrvInfoPtr xkbi = NULL;
if (!IsMaster(master))
return;
if (!master->key)
return;
xkbi = master->key->xkbInfo;
xkbi->lockedPtrButtons = 0;
for (; d; d = d->next) {
if (IsMaster(d) || GetMaster(d, MASTER_KEYBOARD) != master || !d->key)
continue;
xkbi->lockedPtrButtons |= d->key->xkbInfo->lockedPtrButtons;
}
}
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