* keyboard.c (kbd_buffer_get_event): Protect assignment to

	Vlast_event_frame in a "#ifdef MULTI_FRAME" clause.

	Use the term `scroll bar', instead of `scrollbar'.
	* alloc.c, frame.c, frame.h, indent.c, keyboard.c, keyboard.h,
	lisp.h, term.c, termhooks.h, window.c, window.h, xdisp.c, xfns.c,
	xterm.c, xterm.h: Terminology changed.

        Don't generate switch-frame events by checking Vlast_event_frame;
	use a separate variable for that bookkeeping.  In order to
	generate them properly, we may need to fiddle with it.
	* keyboard.c (internal_last_event_frame): New variable.
	(command_loop_1): Check internal_last_event_frame, not
	Vlast_event_frame.
	(read_char, kbd_buffer_store_event): Set both Vlast_event_frame and
	internal_last_event_frame.
	(kbd_buffer_get_event): Check internal_last_event_frame to decide
	whether to generate a switch-frame event.  Set Vlast_event_frame
	after each event.
	(init_keyboard): Initialize both Vlast_event_frame and
	internal_last_event_frame.
	* keyboard.h (internal_last_event_frame): Add extern declaration
	for this.
	* frame.c (Vlast_event_frame): Remove external declaration for
	this.
	(Fselect_frame): Set internal_last_event_frame to Qnil to force a
	switch-frame event, not Vlast_event_frame; the latter is supposed
	to convey information to the user.

	* keyboard.c (syms_of_keyboard): Doc fix for unread_command_events.

1 files changed, 58 insertions, 42 deletions

diff --git a/src/keyboard.c b/src/keyboard.c
index 73be93a0d69..61c57fe4c7e 100644
--- a/src/keyboard.c
+++ b/src/keyboard.c
@@ -205,7 +205,15 @@ Lisp_Object this_command;
 
 #ifdef MULTI_FRAME
 /* The frame in which the last input event occurred, or Qmacro if the
-   last event came from a macro.  */
+   last event came from a macro.  We use this to determine when to
+   generate switch-frame events.  This may be cleared by functions
+   like Fselect_frame, to make sure that a switch-frame event is
+   generated by the next character.  */
+Lisp_Object internal_last_event_frame;
+
+/* A user-visible version of the above, intended to allow users to
+   figure out where the last event came from, if the event doesn't
+   carry that information itself (i.e. if it was a character).  */
 Lisp_Object Vlast_event_frame;
 #endif
 
@@ -248,8 +256,8 @@ static struct input_event kbd_buffer[KBD_BUFFER_SIZE];
 
    The interrupt-level event handlers will never enqueue an event on a
    frame which is not in Vframe_list, and once an event is dequeued,
-   Vlast_event_frame or the event itself points to the frame.  So
-   that's all fine.
+   internal_last_event_frame or the event itself points to the frame.
+   So that's all fine.
 
    But while the event is sitting in the queue, it's completely
    unprotected.  Suppose the user types one command which will run for
@@ -260,7 +268,7 @@ static struct input_event kbd_buffer[KBD_BUFFER_SIZE];
    have an event referring to a freed frame, which will crash Emacs
    when it is dequeued.
 
-   Similar things happen when an event on a scrollbar is enqueued; the
+   Similar things happen when an event on a scroll bar is enqueued; the
    window may be deleted while the event is in the queue.
 
    So, we use this vector to protect the frame_or_window field in the
@@ -318,7 +326,7 @@ int mouse_moved;
 
 /* Symbols to head events.  */
 Lisp_Object Qmouse_movement;
-Lisp_Object Qscrollbar_movement;
+Lisp_Object Qscroll_bar_movement;
 
 Lisp_Object Qswitch_frame;
 
@@ -347,7 +355,7 @@ Lisp_Object Qmodifier_cache;
 /* Symbols to use for non-text mouse positions.  */
 Lisp_Object Qmode_line;
 Lisp_Object Qvertical_line;
-Lisp_Object Qvertical_scrollbar;
+Lisp_Object Qvertical_scroll_bar;
 
 Lisp_Object recursive_edit_unwind (), command_loop ();
 Lisp_Object Fthis_command_keys ();
@@ -884,9 +892,9 @@ command_loop_1 ()
          switch-frame events will take care of this, but if some lisp
          code swallows a switch-frame event, we'll fix things up here.
          Is this a good idea?  */
-      if (XTYPE (Vlast_event_frame) == Lisp_Frame
-          && XFRAME (Vlast_event_frame) != selected_frame)
-        Fselect_frame (Vlast_event_frame, Qnil);
+      if (XTYPE (internal_last_event_frame) == Lisp_Frame
+          && XFRAME (internal_last_event_frame) != selected_frame)
+        Fselect_frame (internal_last_event_frame, Qnil);
 #endif
 #endif
 
@@ -1166,11 +1174,12 @@ read_char (commandflag, nmaps, maps, prev_event, used_mouse_menu)
          remain unchanged.
 
          Since this event came from a macro, it would be misleading to
-         leave Vlast_event_frame set to whereever the last real event
-         came from.  Normally, command_loop_1 selects
-         Vlast_event_frame after each command is read, but events read
-         from a macro should never cause a new frame to be selected.  */
-      Vlast_event_frame = Qmacro;
+         leave internal_last_event_frame set to whereever the last
+         real event came from.  Normally, a switch-frame event selects
+         internal_last_event_frame after each command is read, but
+         events read from a macro should never cause a new frame to be
+         selected. */
+      Vlast_event_frame = internal_last_event_frame = Qmacro;
 #endif
 
       if (executing_macro_index >= XFASTINT (Flength (Vexecuting_macro)))
@@ -1207,7 +1216,8 @@ read_char (commandflag, nmaps, maps, prev_event, used_mouse_menu)
     {
       XSET (c, Lisp_Int, quit_char);
 #ifdef MULTI_FRAME
-      XSET (Vlast_event_frame, Lisp_Frame, selected_frame);
+      XSET (internal_last_event_frame, Lisp_Frame, selected_frame);
+      Vlast_event_frame = internal_last_event_frame;
 #endif
 
       goto non_reread;
@@ -1534,7 +1544,7 @@ kbd_buffer_store_event (event)
 
 #ifdef MULTI_FRAME
           /* If this results in a quit_char being returned to Emacs as
-             input, set last-event-frame properly.  If this doesn't
+             input, set Vlast_event_frame properly.  If this doesn't
              get returned to Emacs as an event, the next event read
              will set Vlast_event_frame again, so this is safe to do.  */
           {
@@ -1542,9 +1552,10 @@ kbd_buffer_store_event (event)
               FRAME_FOCUS_FRAME (XFRAME (event->frame_or_window));
 
             if (NILP (focus))
-              Vlast_event_frame = event->frame_or_window;
+              internal_last_event_frame = event->frame_or_window;
             else
-              Vlast_event_frame = focus;
+              internal_last_event_frame = focus;
+            Vlast_event_frame = internal_last_event_frame;
           }
 #endif
 
@@ -1670,9 +1681,9 @@ kbd_buffer_get_event ()
         if (! NILP (focus))
           frame = focus;
 
-        if (! EQ (frame, Vlast_event_frame))
+        if (! EQ (frame, internal_last_event_frame))
           {
-            Vlast_event_frame = frame;
+            internal_last_event_frame = frame;
             obj = make_lispy_switch_frame (frame);
           }
       }
@@ -1698,7 +1709,7 @@ kbd_buffer_get_event ()
     {
       FRAME_PTR f;
       Lisp_Object bar_window;
-      enum scrollbar_part part;
+      enum scroll_bar_part part;
       Lisp_Object x, y;
       unsigned long time;
 
@@ -1717,10 +1728,10 @@ kbd_buffer_get_event ()
           if (NILP (frame))
             XSET (frame, Lisp_Frame, f);
 
-          if (! EQ (frame, Vlast_event_frame))
+          if (! EQ (frame, internal_last_event_frame))
             {
-              XSET (Vlast_event_frame, Lisp_Frame, frame);
-              obj = make_lispy_switch_frame (Vlast_event_frame);
+              XSET (internal_last_event_frame, Lisp_Frame, frame);
+              obj = make_lispy_switch_frame (internal_last_event_frame);
             }
         }
 #endif
@@ -1737,6 +1748,10 @@ kbd_buffer_get_event ()
 
   input_pending = readable_events ();
 
+#ifdef MULTI_FRAME
+  Vlast_event_frame = internal_last_event_frame;
+#endif
+
   return (obj);
 }
 
@@ -1826,17 +1841,17 @@ static char *lispy_mouse_names[] =
   "mouse-1", "mouse-2", "mouse-3", "mouse-4", "mouse-5"
 };
 
-/* Scrollbar parts.  */
+/* Scroll bar parts.  */
 Lisp_Object Qabove_handle, Qhandle, Qbelow_handle;
 
-/* An array of scrollbar parts, indexed by an enum scrollbar_part value.  */
-Lisp_Object *scrollbar_parts[] = {
+/* An array of scroll bar parts, indexed by an enum scroll_bar_part value.  */
+Lisp_Object *scroll_bar_parts[] = {
   &Qabove_handle, &Qhandle, &Qbelow_handle
 };
 
 
 /* A vector, indexed by button number, giving the down-going location
-   of currently depressed buttons, both scrollbar and non-scrollbar.
+   of currently depressed buttons, both scroll bar and non-scroll bar.
 
    The elements have the form
      (BUTTON-NUMBER MODIFIER-MASK . REST)
@@ -1884,7 +1899,7 @@ make_lispy_event (event)
       /* A mouse click.  Figure out where it is, decide whether it's 
          a press, click or drag, and build the appropriate structure.  */
     case mouse_click:
-    case scrollbar_click:
+    case scroll_bar_click:
       {
         int button = XFASTINT (event->code);
         Lisp_Object position;
@@ -1935,11 +1950,11 @@ make_lispy_event (event)
           {
             Lisp_Object window = event->frame_or_window;
             Lisp_Object portion_whole = Fcons (event->x, event->y);
-            Lisp_Object part = *scrollbar_parts[(int) event->part];
+            Lisp_Object part = *scroll_bar_parts[(int) event->part];
 
             position =
               Fcons (window,
-                     Fcons (Qvertical_scrollbar,
+                     Fcons (Qvertical_scroll_bar,
                             Fcons (portion_whole,
                                    Fcons (make_number (event->timestamp),
                                           Fcons (part,
@@ -2021,18 +2036,18 @@ static Lisp_Object
 make_lispy_movement (frame, bar_window, part, x, y, time)
      FRAME_PTR frame;
      Lisp_Object bar_window;
-     enum scrollbar_part part;
+     enum scroll_bar_part part;
      Lisp_Object x, y;
      unsigned long time;
 {
-  /* Is it a scrollbar movement?  */
+  /* Is it a scroll bar movement?  */
   if (frame && ! NILP (bar_window))
     {
-      Lisp_Object part_sym = *scrollbar_parts[(int) part];
+      Lisp_Object part_sym = *scroll_bar_parts[(int) part];
 
-      return Fcons (Qscrollbar_movement,
+      return Fcons (Qscroll_bar_movement,
                     (Fcons (Fcons (bar_window,
-                                   Fcons (Qvertical_scrollbar,
+                                   Fcons (Qvertical_scroll_bar,
                                           Fcons (Fcons (x, y),
                                                  Fcons (make_number (time),
                                                         Fcons (part_sym,
@@ -3483,8 +3498,8 @@ drag's starting position.  This means that you don't have to distinguish\n\
 between click and drag events unless you want to.\n\
 \n\
 `read-key-sequence' prefixes mouse events on mode lines, the vertical\n\
-lines separating windows, and scrollbars with imaginary keys\n\
-`mode-line', `vertical-line', and `vertical-scrollbar'.\n\
+lines separating windows, and scroll bars with imaginary keys\n\
+`mode-line', `vertical-line', and `vertical-scroll-bar'.\n\
 \n\
 If the user switches frames in the middle of a key sequence, the\n\
 frame-switch event is put off until after the current key sequence.\n\
@@ -4071,7 +4086,8 @@ init_keyboard ()
 #ifdef MULTI_FRAME
   /* This means that command_loop_1 won't try to select anything the first
      time through.  */
-  Vlast_event_frame = Qnil;
+  internal_last_event_frame = Qnil;
+  Vlast_event_frame = internal_last_event_frame;
 #endif
 
   /* If we're running a dumped Emacs, we need to clear out
@@ -4133,7 +4149,7 @@ struct event_head {
 
 struct event_head head_table[] = {
   &Qmouse_movement,     "mouse-movement",       &Qmouse_movement,
-  &Qscrollbar_movement, "scrollbar-movement",   &Qmouse_movement,
+  &Qscroll_bar_movement, "scroll-bar-movement", &Qmouse_movement,
   &Qswitch_frame,       "switch-frame",         &Qswitch_frame,
 };
 
@@ -4160,8 +4176,8 @@ syms_of_keyboard ()
   staticpro (&Qmode_line);
   Qvertical_line = intern ("vertical-line");
   staticpro (&Qvertical_line);
-  Qvertical_scrollbar = intern ("vertical-scrollbar");
-  staticpro (&Qvertical_scrollbar);
+  Qvertical_scroll_bar = intern ("vertical-scroll-bar");
+  staticpro (&Qvertical_scroll_bar);
 
   Qabove_handle = intern ("above-handle");
   staticpro (&Qabove_handle);