Bug 123027

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User-Agent: Mozilla/5.0 Galeon/1.2.7 (X11; Linux i686; U;) Gecko/20030131

Description of problem:
In certain circumstances, popup menus fail when used on
Tarantella and VNC displays. This is seen in Oracle apps
(Oracle bug 3252085).

The problem occurs within _XmGrabPointer(), in motif/lib/Xm/MenuUtil.c
The code calls XGrabPointer() in a retry loop. This fails as
the time is before the Grab time on VNC and Tarantella. Unfortunately
it calls with the same parameters the next 5 times, so it always fails.

_XmGrabPointer() is called within several layers of motif code from
our TK layer, when posting the Motif Popup menu. It failing causes
_XmMenuGrabKeyboardAndPointer() to fail, leading to focus being
redirected away from the popup menu, and hence the wrong widgets get
the events destined for the popup. 

The fix is to detect when XGrabPointer() fails, and change time to
CurrentTime (== 0). This appears to have no implications to other code.

Analysis of the calls at the VNC server end shows that this is is what
the HP Motif code does: its first call at this point uses the value of
time passed from above, and fails, its second uses CurrentTime, which
succeeds. 

This fix has been tested in VNC and Tarantella. 


Version-Release number of selected component (if applicable):


How reproducible:
Always

Steps to Reproduce:
1. Popup menu on a custom widget in Motif (not menu popup)
2. DISPLAY on a VNC or tarantella display
3. trace _XmMenuGrabKeyboardAndPointer(). It fails due to
InvalidGrabTime; 

Actual Results:  =effects depend on test: typically focus is no
longer on popup menu as required    

Expected Results:  It succeeds as on standard X display

Additional info:

Works with HP Motif code; patch applied works on VNC and Tarantella.