[xemacs-hg @ 2003-02-07 11:50:50 by ben] fixes for menu crashes + better preemption behavior This contains two related changes: (1) Fix problems with reentrant calling of lwlib and associated crashes when selecting menu items. (2) Improve redisplay handling of preemption. Turn on lazy lock and hold down page-down or page-up and you'll see what I mean. They are related because they both touch on the code that retrieves events and handles the internal queues. console-msw.h, event-msw.c, event-stream.c, events.h, menubar-msw.c, menubar-x.c, menubar.h: mswindows_protect_modal_loop() has been generalized to event_stream_protect_modal_loop(), and moved to event-stream.c. mswindows_in_modal_loop ->in_modal_loop likewise. Changes in event-msw.c and menubar-msw.c for the new names and calling format (use structures instead of static variables in menubar-msw.c). Delete former in_menu_callback and use in_modal_loop in its place. Remove emacs_mswindows_quit_check_disallowed_p(), superseded by in_modal_loop. Use event_stream_protect_modal_loop() in pre_activate_callback() so that we get no lwlib reentrancy. Rearrange some of the code in event-msw.c to be grouped better. Make mswindows_drain_windows_queue() respect in_modal_loop and do nothing if so. cmdloop.c, event-stream.c: Don't conditionalize on LWLIB_MENUBARS_LUCID when giving error when in_modal_loop, and give better error. event-Xt.c, event-gtk.c: If in_modal_loop, only retrieve process and timeout events. Don't retrieve any X events because processing them can lead to reentrancy in lwlib -> death. event-stream.c: Remove unused parameter to check_event_stream_ok() and change all callers. lisp.h, event-stream.c: Rearrange some functions for increased clarity -- in particular, group all the input-pending/QUIT-related stuff together, and put right next to next-event stuff, to which it's related. Add the concept of "HOW_MANY" -- when asking whether user input is pending, you can ask if at least HOW_MANY events are pending, not just if any are. Add parameter to detect_input_pending() for this. Change recursive_sit_for from a Lisp_Object (which could only be Qt or Qnil) to an int, like it should be. event-Xt.c, event-gtk.c, event-xlike-inc.c: New file. Abstract out similar code in event_{Xt/gtk}_pending_p() and write only once, using include-file tricks. Rewrite this function to implement HOW_MANY and only process events when not in_modal_loop. event-msw.c: Implement HOW_MANY and only process events when not in_modal_loop. event-tty.c: Implement HOW_MANY. redisplay.c: Add var `max-preempts' to control maximum number of preempts. (#### perhaps not useful) Rewrite preemption check so that, rather than preempting when any user events are available, only preempt when a certain number (currently 4) of them are backed up. This effectively allows redisplay to proceed to completion in the presence of a fast auto-repeat (usually the auto-repeating is generated dynamically as necessary), and you get much better display behavior with lazy-lock active. event-unixoid.c: Comment changes. event-stream.c: Rewrite discard-input much more simply and safely using the drain-queue functions. I think the old version might loop forever if called when in_modal_loop. SEMI-UNRELATED CHANGES: ----------------------- event-stream.c: Turn QUIT-checking back on when running the pre-idle hook so it can be quit out of. indent.c: Document exact functioning of `vertical-motion' better, and its differences from GNU Emacs.

--- a/src/events.h	Fri Feb 07 01:43:07 2003 +0000
+++ b/src/events.h	Fri Feb 07 11:50:54 2003 +0000
@@ -65,12 +65,13 @@
  event_pending_cb	A function which says whether there are events to be
 			read.  If called with an argument of 0, then this
 			should say whether calling the next_event_cb will
-			block.  If called with an argument of 1, then this
-			should say whether there are user-generated events
-			pending (that is, keypresses or mouse-clicks).  This
-			is used for redisplay optimization, among other
-			things.  On dumb ttys, these two results are the
-			same, but under a window system, they are not.
+			block.  If called with a non-zero argument, then this
+			should say whether there are that many user-generated
+			events pending (that is, keypresses, mouse-clicks,
+			dialog-box selection events, etc.). (This is used for
+			redisplay optimization, among other things.)  The
+			difference is that the former includes process events
+			and timer events, but the latter doesn't.
 
 			If this function is not sure whether there are events
 			to be read, it *must* return 0.  Otherwise various
@@ -205,7 +206,6 @@
   void (*unselect_console_cb)	(struct console *);
   void (*select_process_cb)	(Lisp_Process *, int doin, int doerr);
   void (*unselect_process_cb)	(Lisp_Process *, int doin, int doerr);
-  int (*quit_check_disallowed_p_cb)(void);
   void (*drain_queue_cb)	(void);
   void (*force_event_pending_cb)(struct frame* f);
   void (*create_io_streams_cb)  (void* /* inhandle*/, void* /*outhandle*/ ,
@@ -1031,6 +1031,7 @@
 EXFUN (Fevent_point, 1);
 EXFUN (Fevent_window, 1);
 EXFUN (Fmake_event, 2);
+EXFUN (Fnext_command_event, 2);
 
 extern Lisp_Object QKbackspace, QKdelete, QKescape, QKlinefeed, QKreturn;
 extern Lisp_Object QKspace, QKtab, Qmouse_event_p, Vcharacter_set_property;
@@ -1127,6 +1128,10 @@
 				     Lisp_Object errstream,
 				     USID* in_usid,
 				     USID* err_usid);
+Lisp_Object event_stream_protect_modal_loop (const char *error_string,
+					     Lisp_Object (*bfun) (void *barg),
+					     void *barg, int flags);
+void event_stream_drain_queue (void);
 void event_stream_quit_p (void);
 void run_pre_idle_hook (void);
 
@@ -1173,7 +1178,7 @@
 int in_single_console_state (void);
 
 extern int emacs_is_blocking;
-
+extern int in_modal_loop;
 extern volatile int sigint_happened;
 
 #ifdef HAVE_UNIXOID_EVENT_LOOP