User: aidan Date: 05/03/02 19:32:00 Modified: xemacs/src ChangeLog select-x.c Log: Wrap call to XtRegisterDrawable with check that XtWindowToWidget gives NULL, document why. Revision Changes Path 1.801 +6 -0 XEmacs/xemacs/src/ChangeLog Index: ChangeLog =================================================================== RCS file: /pack/xemacscvs/XEmacs/xemacs/src/ChangeLog,v retrieving revision 1.800 retrieving revision 1.801 diff -u -r1.800 -r1.801 --- ChangeLog 2005/03/02 13:06:38 1.800 +++ ChangeLog 2005/03/02 18:31:55 1.801 ＠＠ -1,5 +1,11 ＠＠ 2005-03-02 Aidan Kehoe <kehoea(a)parhasard.net&gt; + * select-x.c (x_reply_selection_request): Check that + XtWindowToWidget returns NULL before calling XtRegisterDrawable, + document why. + +2005-03-02 Aidan Kehoe <kehoea(a)parhasard.net&gt; + * select-x.c (x_reply_selection_request): Make the error message in the absence of HAVE_XTREGISTERDRAWABLE more polite, pass a second argument to invalid_operation to have it actually compile 1.23 +18 -2 XEmacs/xemacs/src/select-x.c Index: select-x.c =================================================================== RCS file: /pack/xemacscvs/XEmacs/xemacs/src/select-x.c,v retrieving revision 1.22 retrieving revision 1.23 diff -u -r1.22 -r1.23 --- select-x.c 2005/03/02 13:06:40 1.22 +++ select-x.c 2005/03/02 18:31:57 1.23 ＠＠ -545,8 +545,24 ＠＠ target window, rather, pass them to us. This would be a hack, but the Xt selection routines are broken for our purposes--we can't pass them callbacks from Lisp, for example. Let's call it a - workaround. */ - XtRegisterDrawable(display, (Drawable)window, widget); + workaround. + + The call to wait_for_property_change means we can break out of that + function, switch to another frame on the same display (which will + be another Xt widget), select a huge amount of text, and have the + same (foreign) app ask for another incremental selection + transfer. Programming like X11 made sense, would mean that, in that + case, XtRegisterDrawable is called twice with different widgets. + + Since the results of calling XtRegisterDrawable when the drawable + is already registered with another widget are undefined, we want to + avoid that--so, only call it when XtWindowToWidget returns NULL, + which it will only do with a valid Window if it's not already + registered. */ + if (NULL == XtWindowToWidget(display, window)) + { + XtRegisterDrawable(display, (Drawable)window, widget); + } prop_id = expect_property_change (display, window, reply.property, PropertyDelete);