Patch for building Emacs on Mac OS X. April 26, 2002. See ChangeLog,

lisp/ChangeLog, and src/ChangeLog for list of changes.

1 files changed, 2346 insertions, 0 deletions

diff --git a/src/macmenu.c b/src/macmenu.c
new file mode 100644
index 00000000000..f9498cda67d
--- /dev/null
+++ b/src/macmenu.c
@@ -0,0 +1,2346 @@
+/* Menu support for GNU Emacs on the for Mac OS.
+   Copyright (C) 2000, 2001, 2002 Free Software Foundation, Inc.
+
+This file is part of GNU Emacs.
+
+GNU Emacs is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+GNU Emacs is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Emacs; see the file COPYING.  If not, write to
+the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA.  */
+
+/* Contributed by Andrew Choi (akochoi@mac.com).  */
+
+#include <config.h>
+#include <signal.h>
+
+#include <stdio.h>
+#include "lisp.h"
+#include "termhooks.h"
+#include "keyboard.h"
+#include "keymap.h"
+#include "frame.h"
+#include "window.h"
+#include "blockinput.h"
+#include "buffer.h"
+#include "charset.h"
+#include "coding.h"
+
+#ifdef MAC_OSX
+#undef mktime
+#undef DEBUG
+#undef Z
+#undef free
+#undef malloc
+#undef realloc
+/* Macros max and min defined in lisp.h conflict with those in
+   precompiled header Carbon.h.  */
+#undef max
+#undef min
+#include <Carbon/Carbon.h>
+#undef Z
+#define Z (current_buffer->text->z)
+#undef free
+#define free unexec_free
+#undef malloc
+#define malloc unexec_malloc
+#undef realloc
+#define realloc unexec_realloc
+#undef min
+#define min(a, b) ((a) < (b) ? (a) : (b))
+#undef max
+#define max(a, b) ((a) > (b) ? (a) : (b))
+#else /* not MAC_OSX */
+#include <MacTypes.h>
+#include <Menus.h>
+#include <QuickDraw.h>
+#include <ToolUtils.h>
+#include <Fonts.h>
+#include <Controls.h>
+#include <Windows.h>
+#include <Events.h>
+#if defined (__MRC__) || (__MSL__ >= 0x6000)
+#include <ControlDefinitions.h>
+#endif
+#endif /* not MAC_OSX */
+
+/* This may include sys/types.h, and that somehow loses
+   if this is not done before the other system files.  */
+#include "macterm.h"
+
+/* Load sys/types.h if not already loaded.
+   In some systems loading it twice is suicidal.  */
+#ifndef makedev
+#include <sys/types.h>
+#endif
+
+#include "dispextern.h"
+
+#define POPUP_SUBMENU_ID 235
+#define MIN_MENU_ID 256
+#define MIN_SUBMENU_ID 1
+
+#define DIALOG_WINDOW_RESOURCE 130
+
+#define HAVE_DIALOGS 1
+
+#undef HAVE_MULTILINGUAL_MENU
+#undef HAVE_DIALOGS /* TODO: Implement native dialogs.  */
+
+/******************************************************************/
+/* Definitions copied from lwlib.h */
+
+typedef void * XtPointer;
+
+enum button_type
+{
+  BUTTON_TYPE_NONE,
+  BUTTON_TYPE_TOGGLE,
+  BUTTON_TYPE_RADIO
+};
+
+/* This structure is based on the one in ../lwlib/lwlib.h, modified
+   for Mac OS.  */
+typedef struct _widget_value
+{
+  /* name of widget */
+  char*		name;
+  /* value (meaning depend on widget type) */
+  char*		value;
+  /* keyboard equivalent. no implications for XtTranslations */ 
+  char*		key;
+  /* Help string or nil if none.
+     GC finds this string through the frame's menu_bar_vector
+     or through menu_items.  */
+  Lisp_Object	help;
+  /* true if enabled */
+  Boolean	enabled;
+  /* true if selected */
+  Boolean	selected;
+  /* The type of a button.  */
+  enum button_type button_type;
+  /* true if menu title */
+  Boolean       title;
+#if 0
+  /* true if was edited (maintained by get_value) */
+  Boolean	edited;
+  /* true if has changed (maintained by lw library) */
+  change_type	change;
+  /* true if this widget itself has changed,
+     but not counting the other widgets found in the `next' field.  */
+  change_type   this_one_change;
+#endif
+  /* Contents of the sub-widgets, also selected slot for checkbox */
+  struct _widget_value*	contents;
+  /* data passed to callback */
+  XtPointer	call_data;
+  /* next one in the list */
+  struct _widget_value*	next;
+#if 0
+  /* slot for the toolkit dependent part.  Always initialize to NULL. */
+  void* toolkit_data;
+  /* tell us if we should free the toolkit data slot when freeing the
+     widget_value itself. */
+  Boolean free_toolkit_data;
+
+  /* we resource the widget_value structures; this points to the next
+     one on the free list if this one has been deallocated.
+   */
+  struct _widget_value *free_list;
+#endif
+} widget_value;
+
+/* Assumed by other routines to zero area returned.  */
+#define malloc_widget_value() (void *)memset (xmalloc (sizeof (widget_value)),\
+                                              0, (sizeof (widget_value)))
+#define free_widget_value(wv) xfree (wv)
+
+/******************************************************************/
+
+#ifndef TRUE
+#define TRUE 1
+#define FALSE 0
+#endif /* no TRUE */
+
+Lisp_Object Vmenu_updating_frame;
+
+Lisp_Object Qdebug_on_next_call;
+
+extern Lisp_Object Qmenu_bar;
+extern Lisp_Object Qmouse_click, Qevent_kind;
+
+extern Lisp_Object QCtoggle, QCradio;
+
+extern Lisp_Object Voverriding_local_map;
+extern Lisp_Object Voverriding_local_map_menu_flag;
+
+extern Lisp_Object Qoverriding_local_map, Qoverriding_terminal_local_map;
+
+extern Lisp_Object Qmenu_bar_update_hook;
+
+void set_frame_menubar ();
+
+static void push_menu_item P_ ((Lisp_Object, Lisp_Object, Lisp_Object,
+				Lisp_Object, Lisp_Object, Lisp_Object,
+				Lisp_Object, Lisp_Object));
+#ifdef HAVE_DIALOGS
+static Lisp_Object mac_dialog_show ();
+#endif
+static Lisp_Object mac_menu_show ();
+
+static void keymap_panes ();
+static void single_keymap_panes ();
+static void single_menu_item ();
+static void list_of_panes ();
+static void list_of_items ();
+
+static void fill_submenu (MenuHandle, widget_value *, int);
+static void fill_menubar (widget_value *);
+
+
+/* This holds a Lisp vector that holds the results of decoding
+   the keymaps or alist-of-alists that specify a menu.
+
+   It describes the panes and items within the panes.
+
+   Each pane is described by 3 elements in the vector:
+   t, the pane name, the pane's prefix key.
+   Then follow the pane's items, with 5 elements per item:
+   the item string, the enable flag, the item's value,
+   the definition, and the equivalent keyboard key's description string.
+
+   In some cases, multiple levels of menus may be described.
+   A single vector slot containing nil indicates the start of a submenu.
+   A single vector slot containing lambda indicates the end of a submenu.
+   The submenu follows a menu item which is the way to reach the submenu.
+
+   A single vector slot containing quote indicates that the
+   following items should appear on the right of a dialog box.
+
+   Using a Lisp vector to hold this information while we decode it
+   takes care of protecting all the data from GC.  */
+
+#define MENU_ITEMS_PANE_NAME 1
+#define MENU_ITEMS_PANE_PREFIX 2
+#define MENU_ITEMS_PANE_LENGTH 3
+
+enum menu_item_idx
+{
+  MENU_ITEMS_ITEM_NAME = 0,
+  MENU_ITEMS_ITEM_ENABLE,
+  MENU_ITEMS_ITEM_VALUE,
+  MENU_ITEMS_ITEM_EQUIV_KEY,
+  MENU_ITEMS_ITEM_DEFINITION,
+  MENU_ITEMS_ITEM_TYPE,
+  MENU_ITEMS_ITEM_SELECTED,
+  MENU_ITEMS_ITEM_HELP,
+  MENU_ITEMS_ITEM_LENGTH
+};
+
+static Lisp_Object menu_items;
+
+/* Number of slots currently allocated in menu_items.  */
+static int menu_items_allocated;
+
+/* This is the index in menu_items of the first empty slot.  */
+static int menu_items_used;
+
+/* The number of panes currently recorded in menu_items,
+   excluding those within submenus.  */
+static int menu_items_n_panes;
+
+/* Current depth within submenus.  */
+static int menu_items_submenu_depth;
+
+/* Flag which when set indicates a dialog or menu has been posted by
+   Xt on behalf of one of the widget sets.  */
+static int popup_activated_flag;
+
+static int next_menubar_widget_id;
+
+/* This is set nonzero after the user activates the menu bar, and set
+   to zero again after the menu bars are redisplayed by prepare_menu_bar.
+   While it is nonzero, all calls to set_frame_menubar go deep.
+
+   I don't understand why this is needed, but it does seem to be
+   needed on Motif, according to Marcus Daniels <marcus@sysc.pdx.edu>.  */
+
+int pending_menu_activation;
+
+/* Initialize the menu_items structure if we haven't already done so.
+   Also mark it as currently empty.  */
+
+static void
+init_menu_items ()
+{
+  if (NILP (menu_items))
+    {
+      menu_items_allocated = 60;
+      menu_items = Fmake_vector (make_number (menu_items_allocated), Qnil);
+    }
+
+  menu_items_used = 0;
+  menu_items_n_panes = 0;
+  menu_items_submenu_depth = 0;
+}
+
+/* Call at the end of generating the data in menu_items.
+   This fills in the number of items in the last pane.  */
+
+static void
+finish_menu_items ()
+{
+}
+
+/* Call when finished using the data for the current menu
+   in menu_items.  */
+
+static void
+discard_menu_items ()
+{
+  /* Free the structure if it is especially large.
+     Otherwise, hold on to it, to save time.  */
+  if (menu_items_allocated > 200)
+    {
+      menu_items = Qnil;
+      menu_items_allocated = 0;
+    }
+}
+
+/* Make the menu_items vector twice as large.  */
+
+static void
+grow_menu_items ()
+{
+  Lisp_Object old;
+  int old_size = menu_items_allocated;
+  old = menu_items;
+
+  menu_items_allocated *= 2;
+  menu_items = Fmake_vector (make_number (menu_items_allocated), Qnil);
+  bcopy (XVECTOR (old)->contents, XVECTOR (menu_items)->contents,
+	 old_size * sizeof (Lisp_Object));
+}
+
+/* Begin a submenu.  */
+
+static void
+push_submenu_start ()
+{
+  if (menu_items_used + 1 > menu_items_allocated)
+    grow_menu_items ();
+
+  XVECTOR (menu_items)->contents[menu_items_used++] = Qnil;
+  menu_items_submenu_depth++;
+}
+
+/* End a submenu.  */
+
+static void
+push_submenu_end ()
+{
+  if (menu_items_used + 1 > menu_items_allocated)
+    grow_menu_items ();
+
+  XVECTOR (menu_items)->contents[menu_items_used++] = Qlambda;
+  menu_items_submenu_depth--;
+}
+
+/* Indicate boundary between left and right.  */
+
+static void
+push_left_right_boundary ()
+{
+  if (menu_items_used + 1 > menu_items_allocated)
+    grow_menu_items ();
+
+  XVECTOR (menu_items)->contents[menu_items_used++] = Qquote;
+}
+
+/* Start a new menu pane in menu_items.
+   NAME is the pane name.  PREFIX_VEC is a prefix key for this pane.  */
+
+static void
+push_menu_pane (name, prefix_vec)
+     Lisp_Object name, prefix_vec;
+{
+  if (menu_items_used + MENU_ITEMS_PANE_LENGTH > menu_items_allocated)
+    grow_menu_items ();
+
+  if (menu_items_submenu_depth == 0)
+    menu_items_n_panes++;
+  XVECTOR (menu_items)->contents[menu_items_used++] = Qt;
+  XVECTOR (menu_items)->contents[menu_items_used++] = name;
+  XVECTOR (menu_items)->contents[menu_items_used++] = prefix_vec;
+}
+
+/* Push one menu item into the current pane.  NAME is the string to
+   display.  ENABLE if non-nil means this item can be selected.  KEY
+   is the key generated by choosing this item, or nil if this item
+   doesn't really have a definition.  DEF is the definition of this
+   item.  EQUIV is the textual description of the keyboard equivalent
+   for this item (or nil if none).  TYPE is the type of this menu
+   item, one of nil, `toggle' or `radio'. */
+
+static void
+push_menu_item (name, enable, key, def, equiv, type, selected, help)
+     Lisp_Object name, enable, key, def, equiv, type, selected, help;
+{
+  if (menu_items_used + MENU_ITEMS_ITEM_LENGTH > menu_items_allocated)
+    grow_menu_items ();
+
+  XVECTOR (menu_items)->contents[menu_items_used++] = name;
+  XVECTOR (menu_items)->contents[menu_items_used++] = enable;
+  XVECTOR (menu_items)->contents[menu_items_used++] = key;
+  XVECTOR (menu_items)->contents[menu_items_used++] = equiv;
+  XVECTOR (menu_items)->contents[menu_items_used++] = def;
+  XVECTOR (menu_items)->contents[menu_items_used++] = type;
+  XVECTOR (menu_items)->contents[menu_items_used++] = selected;
+  XVECTOR (menu_items)->contents[menu_items_used++] = help;
+}
+
+/* Look through KEYMAPS, a vector of keymaps that is NMAPS long,
+   and generate menu panes for them in menu_items.
+   If NOTREAL is nonzero,
+   don't bother really computing whether an item is enabled.  */
+
+static void
+keymap_panes (keymaps, nmaps, notreal)
+     Lisp_Object *keymaps;
+     int nmaps;
+     int notreal;
+{
+  int mapno;
+
+  init_menu_items ();
+
+  /* Loop over the given keymaps, making a pane for each map.
+     But don't make a pane that is empty--ignore that map instead.
+     P is the number of panes we have made so far.  */
+  for (mapno = 0; mapno < nmaps; mapno++)
+    single_keymap_panes (keymaps[mapno],
+                         Fkeymap_prompt (keymaps[mapno]), Qnil, notreal, 10);
+
+  finish_menu_items ();
+}
+
+/* This is a recursive subroutine of keymap_panes.
+   It handles one keymap, KEYMAP.
+   The other arguments are passed along
+   or point to local variables of the previous function.
+   If NOTREAL is nonzero, only check for equivalent key bindings, don't
+   evaluate expressions in menu items and don't make any menu.
+
+   If we encounter submenus deeper than MAXDEPTH levels, ignore them.  */
+
+static void
+single_keymap_panes (keymap, pane_name, prefix, notreal, maxdepth)
+     Lisp_Object keymap;
+     Lisp_Object pane_name;
+     Lisp_Object prefix;
+     int notreal;
+     int maxdepth;
+{
+  Lisp_Object pending_maps = Qnil;
+  Lisp_Object tail, item;
+  struct gcpro gcpro1, gcpro2;
+
+  if (maxdepth <= 0)
+    return;
+
+  push_menu_pane (pane_name, prefix);
+
+  for (tail = keymap; CONSP (tail); tail = XCDR (tail))
+    {
+      GCPRO2 (keymap, pending_maps);
+      /* Look at each key binding, and if it is a menu item add it
+	 to this menu.  */
+      item = XCAR (tail);
+      if (CONSP (item))
+	single_menu_item (XCAR (item), XCDR (item),
+			  &pending_maps, notreal, maxdepth);
+      else if (VECTORP (item))
+	{
+	  /* Loop over the char values represented in the vector.  */
+	  int len = XVECTOR (item)->size;
+	  int c;
+	  for (c = 0; c < len; c++)
+	    {
+	      Lisp_Object character;
+	      XSETFASTINT (character, c);
+	      single_menu_item (character, XVECTOR (item)->contents[c],
+				&pending_maps, notreal, maxdepth);
+	    }
+	}
+      UNGCPRO;
+    }
+
+  /* Process now any submenus which want to be panes at this level.  */
+  while (!NILP (pending_maps))
+    {
+      Lisp_Object elt, eltcdr, string;
+      elt = Fcar (pending_maps);
+      eltcdr = XCDR (elt);
+      string = XCAR (eltcdr);
+      /* We no longer discard the @ from the beginning of the string here.
+	 Instead, we do this in mac_menu_show.  */
+      single_keymap_panes (Fcar (elt), string,
+			   XCDR (eltcdr), notreal, maxdepth - 1);
+      pending_maps = Fcdr (pending_maps);
+    }
+}
+
+/* This is a subroutine of single_keymap_panes that handles one
+   keymap entry.
+   KEY is a key in a keymap and ITEM is its binding. 
+   PENDING_MAPS_PTR points to a list of keymaps waiting to be made into
+   separate panes.
+   If NOTREAL is nonzero, only check for equivalent key bindings, don't
+   evaluate expressions in menu items and don't make any menu.
+   If we encounter submenus deeper than MAXDEPTH levels, ignore them.  */
+
+static void
+single_menu_item (key, item, pending_maps_ptr, notreal, maxdepth)
+     Lisp_Object key, item;
+     Lisp_Object *pending_maps_ptr;
+     int maxdepth, notreal;
+{
+  Lisp_Object map, item_string, enabled;
+  struct gcpro gcpro1, gcpro2;
+  int res;
+  
+  /* Parse the menu item and leave the result in item_properties.  */
+  GCPRO2 (key, item);
+  res = parse_menu_item (item, notreal, 0);
+  UNGCPRO;
+  if (!res)
+    return;			/* Not a menu item.  */
+
+  map = XVECTOR (item_properties)->contents[ITEM_PROPERTY_MAP];
+  
+  if (notreal)
+    {
+      /* We don't want to make a menu, just traverse the keymaps to
+	 precompute equivalent key bindings.  */
+      if (!NILP (map))
+	single_keymap_panes (map, Qnil, key, 1, maxdepth - 1);
+      return;
+    }
+
+  enabled = XVECTOR (item_properties)->contents[ITEM_PROPERTY_ENABLE];
+  item_string = XVECTOR (item_properties)->contents[ITEM_PROPERTY_NAME]; 
+
+  if (!NILP (map) && XSTRING (item_string)->data[0] == '@')
+    {
+      if (!NILP (enabled))
+	/* An enabled separate pane. Remember this to handle it later.  */
+	*pending_maps_ptr = Fcons (Fcons (map, Fcons (item_string, key)),
+				   *pending_maps_ptr);
+      return;
+    }
+
+  push_menu_item (item_string, enabled, key,
+		  XVECTOR (item_properties)->contents[ITEM_PROPERTY_DEF],
+		  XVECTOR (item_properties)->contents[ITEM_PROPERTY_KEYEQ],
+		  XVECTOR (item_properties)->contents[ITEM_PROPERTY_TYPE],
+                  XVECTOR (item_properties)->contents[ITEM_PROPERTY_SELECTED],
+                  XVECTOR (item_properties)->contents[ITEM_PROPERTY_HELP]);
+
+  /* Display a submenu using the toolkit.  */
+  if (! (NILP (map) || NILP (enabled)))
+    {
+      push_submenu_start ();
+      single_keymap_panes (map, Qnil, key, 0, maxdepth - 1);
+      push_submenu_end ();
+    }
+}
+
+/* Push all the panes and items of a menu described by the
+   alist-of-alists MENU.
+   This handles old-fashioned calls to x-popup-menu.  */
+
+static void
+list_of_panes (menu)
+     Lisp_Object menu;
+{
+  Lisp_Object tail;
+
+  init_menu_items ();
+
+  for (tail = menu; !NILP (tail); tail = Fcdr (tail))
+    {
+      Lisp_Object elt, pane_name, pane_data;
+      elt = Fcar (tail);
+      pane_name = Fcar (elt);
+      CHECK_STRING (pane_name);
+      push_menu_pane (pane_name, Qnil);
+      pane_data = Fcdr (elt);
+      CHECK_CONS (pane_data);
+      list_of_items (pane_data);
+    }
+
+  finish_menu_items ();
+}
+
+/* Push the items in a single pane defined by the alist PANE.  */
+
+static void
+list_of_items (pane)
+     Lisp_Object pane;
+{
+  Lisp_Object tail, item, item1;
+
+  for (tail = pane; !NILP (tail); tail = Fcdr (tail))
+    {
+      item = Fcar (tail);
+      if (STRINGP (item))
+	push_menu_item (item, Qnil, Qnil, Qt, Qnil, Qnil, Qnil, Qnil);
+      else if (NILP (item))
+	push_left_right_boundary ();
+      else
+	{
+	  CHECK_CONS (item);
+	  item1 = Fcar (item);
+	  CHECK_STRING (item1);
+	  push_menu_item (item1, Qt, Fcdr (item), Qt, Qnil, Qnil, Qnil, Qnil);
+	}
+    }
+}
+
+DEFUN ("x-popup-menu", Fx_popup_menu, Sx_popup_menu, 2, 2, 0,
+       doc: /* Pop up a deck-of-cards menu and return user's selection.
+POSITION is a position specification.  This is either a mouse button
+event or a list ((XOFFSET YOFFSET) WINDOW) where XOFFSET and YOFFSET
+are positions in pixels from the top left corner of WINDOW's frame
+\(WINDOW may be a frame object instead of a window).  This controls the
+position of the center of the first line in the first pane of the
+menu, not the top left of the menu as a whole.  If POSITION is t, it
+means to use the current mouse position.
+
+MENU is a specifier for a menu.  For the simplest case, MENU is a keymap.
+The menu items come from key bindings that have a menu string as well as
+a definition; actually, the \"definition\" in such a key binding looks like
+\(STRING . REAL-DEFINITION).  To give the menu a title, put a string into
+the keymap as a top-level element.
+
+If REAL-DEFINITION is nil, that puts a nonselectable string in the menu.
+Otherwise, REAL-DEFINITION should be a valid key binding definition.
+
+You can also use a list of keymaps as MENU.  Then each keymap makes a
+separate pane.  When MENU is a keymap or a list of keymaps, the return
+value is a list of events.
+
+Alternatively, you can specify a menu of multiple panes with a list of
+the form (TITLE PANE1 PANE2...), where each pane is a list of
+form (TITLE ITEM1 ITEM2...).
+Each ITEM is normally a cons cell (STRING . VALUE); but a string can
+appear as an item--that makes a nonselectable line in the menu.
+With this form of menu, the return value is VALUE from the chosen item.
+
+If POSITION is nil, don't display the menu at all, just precalculate the
+cached information about equivalent key sequences.  */)
+  (position, menu)
+     Lisp_Object position, menu;
+{
+  Lisp_Object keymap, tem;
+  int xpos = 0, ypos = 0;
+  Lisp_Object title;
+  char *error_name;
+  Lisp_Object selection;
+  FRAME_PTR f = NULL;
+  Lisp_Object x, y, window;
+  int keymaps = 0;
+  int for_click = 0;
+  struct gcpro gcpro1;
+
+#ifdef HAVE_MENUS
+  if (! NILP (position))
+    {
+      check_mac ();
+
+      /* Decode the first argument: find the window and the coordinates.  */
+      if (EQ (position, Qt)
+	  || (CONSP (position) && (EQ (XCAR (position), Qmenu_bar)
+                                   || EQ (XCAR (position), Qtool_bar))))
+	{
+	  /* Use the mouse's current position.  */
+	  FRAME_PTR new_f = SELECTED_FRAME ();
+	  Lisp_Object bar_window;
+	  enum scroll_bar_part part;
+	  unsigned long time;
+
+	  if (mouse_position_hook)
+	    (*mouse_position_hook) (&new_f, 1, &bar_window,
+				    &part, &x, &y, &time);
+	  if (new_f != 0)
+	    XSETFRAME (window, new_f);
+	  else
+	    {
+	      window = selected_window;
+	      XSETFASTINT (x, 0);
+	      XSETFASTINT (y, 0);
+	    }
+	}
+      else
+	{
+	  tem = Fcar (position);
+	  if (CONSP (tem))
+	    {
+	      window = Fcar (Fcdr (position));
+	      x = Fcar (tem);
+	      y = Fcar (Fcdr (tem));
+	    }
+	  else
+	    {
+	      for_click = 1;
+	      tem = Fcar (Fcdr (position));  /* EVENT_START (position) */
+	      window = Fcar (tem);	     /* POSN_WINDOW (tem) */
+	      tem = Fcar (Fcdr (Fcdr (tem))); /* POSN_WINDOW_POSN (tem) */
+	      x = Fcar (tem);
+	      y = Fcdr (tem);
+	    }
+	}
+
+      CHECK_NUMBER (x);
+      CHECK_NUMBER (y);
+
+      /* Decode where to put the menu.  */
+
+      if (FRAMEP (window))
+	{
+	  f = XFRAME (window);
+	  xpos = 0;
+	  ypos = 0;
+	}
+      else if (WINDOWP (window))
+	{
+	  CHECK_LIVE_WINDOW (window);
+	  f = XFRAME (WINDOW_FRAME (XWINDOW (window)));
+
+	  xpos = (FONT_WIDTH (FRAME_FONT (f))
+		  * XFASTINT (XWINDOW (window)->left));
+	  ypos = (FRAME_LINE_HEIGHT (f)
+		  * XFASTINT (XWINDOW (window)->top));
+	}
+      else
+	/* ??? Not really clean; should be CHECK_WINDOW_OR_FRAME,
+	   but I don't want to make one now.  */
+	CHECK_WINDOW (window);
+
+      xpos += XINT (x);
+      ypos += XINT (y);
+
+      XSETFRAME (Vmenu_updating_frame, f);
+    }
+  Vmenu_updating_frame = Qnil;
+#endif /* HAVE_MENUS */
+
+  title = Qnil;
+  GCPRO1 (title);
+
+  /* Decode the menu items from what was specified.  */
+
+  keymap = get_keymap (menu, 0, 0);
+  if (CONSP (keymap))
+    {
+      /* We were given a keymap.  Extract menu info from the keymap.  */
+      Lisp_Object prompt;
+
+      /* Extract the detailed info to make one pane.  */
+      keymap_panes (&menu, 1, NILP (position));
+
+      /* Search for a string appearing directly as an element of the keymap.
+	 That string is the title of the menu.  */
+      prompt = Fkeymap_prompt (keymap);
+      if (NILP (title) && !NILP (prompt))
+	title = prompt;
+
+      /* Make that be the pane title of the first pane.  */
+      if (!NILP (prompt) && menu_items_n_panes >= 0)
+	XVECTOR (menu_items)->contents[MENU_ITEMS_PANE_NAME] = prompt;
+
+      keymaps = 1;
+    }
+  else if (CONSP (menu) && KEYMAPP (XCAR (menu)))
+    {
+      /* We were given a list of keymaps.  */
+      int nmaps = XFASTINT (Flength (menu));
+      Lisp_Object *maps
+	= (Lisp_Object *) alloca (nmaps * sizeof (Lisp_Object));
+      int i;
+
+      title = Qnil;
+
+      /* The first keymap that has a prompt string
+	 supplies the menu title.  */
+      for (tem = menu, i = 0; CONSP (tem); tem = Fcdr (tem))
+	{
+	  Lisp_Object prompt;
+
+	  maps[i++] = keymap = get_keymap (Fcar (tem), 1, 0);
+
+	  prompt = Fkeymap_prompt (keymap);
+	  if (NILP (title) && !NILP (prompt))
+	    title = prompt;
+	}
+
+      /* Extract the detailed info to make one pane.  */
+      keymap_panes (maps, nmaps, NILP (position));
+
+      /* Make the title be the pane title of the first pane.  */
+      if (!NILP (title) && menu_items_n_panes >= 0)
+	XVECTOR (menu_items)->contents[MENU_ITEMS_PANE_NAME] = title;
+
+      keymaps = 1;
+    }
+  else
+    {
+      /* We were given an old-fashioned menu.  */
+      title = Fcar (menu);
+      CHECK_STRING (title);
+
+      list_of_panes (Fcdr (menu));
+
+      keymaps = 0;
+    }
+  
+  if (NILP (position))
+    {
+      discard_menu_items ();
+      UNGCPRO;
+      return Qnil;
+    }
+
+#ifdef HAVE_MENUS
+  /* Display them in a menu.  */
+  BLOCK_INPUT;
+
+  selection = mac_menu_show (f, xpos, ypos, for_click,
+			     keymaps, title, &error_name);
+  UNBLOCK_INPUT;
+
+  discard_menu_items ();
+
+  UNGCPRO;
+#endif /* HAVE_MENUS */
+
+  if (error_name) error (error_name);
+  return selection;
+}
+
+#ifdef HAVE_MENUS
+
+DEFUN ("x-popup-dialog", Fx_popup_dialog, Sx_popup_dialog, 2, 2, 0,
+       doc: /* Pop up a dialog box and return user's selection.
+POSITION specifies which frame to use.
+This is normally a mouse button event or a window or frame.
+If POSITION is t, it means to use the frame the mouse is on.
+The dialog box appears in the middle of the specified frame.
+
+CONTENTS specifies the alternatives to display in the dialog box.
+It is a list of the form (TITLE ITEM1 ITEM2...).
+Each ITEM is a cons cell (STRING . VALUE).
+The return value is VALUE from the chosen item.
+
+An ITEM may also be just a string--that makes a nonselectable item.
+An ITEM may also be nil--that means to put all preceding items
+on the left of the dialog box and all following items on the right.
+\(By default, approximately half appear on each side.)  */)
+  (position, contents)
+     Lisp_Object position, contents;
+{
+  FRAME_PTR f = NULL;
+  Lisp_Object window;
+
+  check_mac ();
+
+  /* Decode the first argument: find the window or frame to use.  */
+  if (EQ (position, Qt)
+      || (CONSP (position) && (EQ (XCAR (position), Qmenu_bar)
+                               || EQ (XCAR (position), Qtool_bar))))
+    {
+#if 0 /* Using the frame the mouse is on may not be right.  */
+      /* Use the mouse's current position.  */
+      FRAME_PTR new_f = SELECTED_FRAME ();
+      Lisp_Object bar_window;
+      enum scroll_bar_part part;
+      unsigned long time;
+      Lisp_Object x, y;
+
+      (*mouse_position_hook) (&new_f, 1, &bar_window, &part, &x, &y, &time);
+
+      if (new_f != 0)
+	XSETFRAME (window, new_f);
+      else
+	window = selected_window;
+#endif
+      window = selected_window;
+    }
+  else if (CONSP (position))
+    {
+      Lisp_Object tem;
+      tem = Fcar (position);
+      if (CONSP (tem))
+	window = Fcar (Fcdr (position));
+      else
+	{
+	  tem = Fcar (Fcdr (position));  /* EVENT_START (position) */
+	  window = Fcar (tem);	     /* POSN_WINDOW (tem) */
+	}
+    }
+  else if (WINDOWP (position) || FRAMEP (position))
+    window = position;
+  else
+    window = Qnil;
+
+  /* Decode where to put the menu.  */
+
+  if (FRAMEP (window))
+    f = XFRAME (window);
+  else if (WINDOWP (window))
+    {
+      CHECK_LIVE_WINDOW (window);
+      f = XFRAME (WINDOW_FRAME (XWINDOW (window)));
+    }
+  else
+    /* ??? Not really clean; should be CHECK_WINDOW_OR_FRAME,
+       but I don't want to make one now.  */
+    CHECK_WINDOW (window);
+
+#ifndef HAVE_DIALOGS
+  /* Display a menu with these alternatives
+     in the middle of frame F.  */
+  {
+    Lisp_Object x, y, frame, newpos;
+    XSETFRAME (frame, f);
+    XSETINT (x, x_pixel_width (f) / 2);
+    XSETINT (y, x_pixel_height (f) / 2);
+    newpos = Fcons (Fcons (x, Fcons (y, Qnil)), Fcons (frame, Qnil));
+
+    return Fx_popup_menu (newpos,
+			  Fcons (Fcar (contents), Fcons (contents, Qnil)));
+  }
+#else /* HAVE_DIALOGS */
+  {
+    Lisp_Object title;
+    char *error_name;
+    Lisp_Object selection;
+
+    /* Decode the dialog items from what was specified.  */
+    title = Fcar (contents);
+    CHECK_STRING (title);
+
+    list_of_panes (Fcons (contents, Qnil));
+
+    /* Display them in a dialog box.  */
+    BLOCK_INPUT;
+    selection = mac_dialog_show (f, 0, title, &error_name);
+    UNBLOCK_INPUT;
+
+    discard_menu_items ();
+
+    if (error_name) error (error_name);
+    return selection;
+  }
+#endif /* HAVE_DIALOGS */
+}
+
+/* Activate the menu bar of frame F.
+   This is called from keyboard.c when it gets the
+   menu_bar_activate_event out of the Emacs event queue.
+
+   To activate the menu bar, we signal to the input thread that it can
+   return from the WM_INITMENU message, allowing the normal Windows
+   processing of the menus.
+
+   But first we recompute the menu bar contents (the whole tree).
+
+   This way we can safely execute Lisp code.  */
+   
+void
+x_activate_menubar (f)
+     FRAME_PTR f;
+{
+  SInt32 menu_choice;
+  extern Point saved_menu_event_location;
+
+  set_frame_menubar (f, 0, 1);
+  BLOCK_INPUT;
+
+  menu_choice = MenuSelect (saved_menu_event_location);
+  do_menu_choice (menu_choice);
+
+  UNBLOCK_INPUT;
+}
+
+/* This callback is called from the menu bar pulldown menu
+   when the user makes a selection.
+   Figure out what the user chose
+   and put the appropriate events into the keyboard buffer.  */
+
+void
+menubar_selection_callback (FRAME_PTR f, int client_data)
+{
+  Lisp_Object prefix, entry;
+  Lisp_Object vector;
+  Lisp_Object *subprefix_stack;
+  int submenu_depth = 0;
+  int i;
+
+  if (!f)
+    return;
+  entry = Qnil;
+  subprefix_stack = (Lisp_Object *) alloca (f->menu_bar_items_used * sizeof (Lisp_Object));
+  vector = f->menu_bar_vector;
+  prefix = Qnil;
+  i = 0;
+  while (i < f->menu_bar_items_used)
+    {
+      if (EQ (XVECTOR (vector)->contents[i], Qnil))
+	{
+	  subprefix_stack[submenu_depth++] = prefix;
+	  prefix = entry;
+	  i++;
+	}
+      else if (EQ (XVECTOR (vector)->contents[i], Qlambda))
+	{
+	  prefix = subprefix_stack[--submenu_depth];
+	  i++;
+	}
+      else if (EQ (XVECTOR (vector)->contents[i], Qt))
+	{
+	  prefix = XVECTOR (vector)->contents[i + MENU_ITEMS_PANE_PREFIX];
+	  i += MENU_ITEMS_PANE_LENGTH;
+	}
+      else
+	{
+	  entry = XVECTOR (vector)->contents[i + MENU_ITEMS_ITEM_VALUE];
+	  /* The EMACS_INT cast avoids a warning.  There's no problem
+	     as long as pointers have enough bits to hold small integers.  */
+	  if ((int) (EMACS_INT) client_data == i)
+	    {
+	      int j;
+	      struct input_event buf;
+	      Lisp_Object frame;
+
+	      XSETFRAME (frame, f);
+	      buf.kind = MENU_BAR_EVENT;
+	      buf.frame_or_window = frame;
+	      buf.arg = frame;
+	      kbd_buffer_store_event (&buf);
+
+	      for (j = 0; j < submenu_depth; j++)
+		if (!NILP (subprefix_stack[j]))
+		  {
+		    buf.kind = MENU_BAR_EVENT;
+		    buf.frame_or_window = frame;
+		    buf.arg = subprefix_stack[j];
+		    kbd_buffer_store_event (&buf);
+		  }
+
+	      if (!NILP (prefix))
+		{
+		  buf.kind = MENU_BAR_EVENT;
+		  buf.frame_or_window = frame;
+		  buf.arg = prefix;
+		  kbd_buffer_store_event (&buf);
+		}
+
+	      buf.kind = MENU_BAR_EVENT;
+	      buf.frame_or_window = frame;
+	      buf.arg = entry;
+	      kbd_buffer_store_event (&buf);
+
+	      f->output_data.mac->menu_command_in_progress = 0;
+	      f->output_data.mac->menubar_active = 0;
+	      return;
+	    }
+	  i += MENU_ITEMS_ITEM_LENGTH;
+	}
+    }
+  f->output_data.mac->menu_command_in_progress = 0;
+  f->output_data.mac->menubar_active = 0;
+}
+
+/* Allocate a widget_value, blocking input.  */
+
+widget_value *
+xmalloc_widget_value ()
+{
+  widget_value *value;
+
+  BLOCK_INPUT;
+  value = malloc_widget_value ();
+  UNBLOCK_INPUT;
+
+  return value;
+}
+
+/* This recursively calls free_widget_value on the tree of widgets.
+   It must free all data that was malloc'ed for these widget_values.
+   In Emacs, many slots are pointers into the data of Lisp_Strings, and
+   must be left alone.  */
+
+void
+free_menubar_widget_value_tree (wv)
+     widget_value *wv;
+{
+  if (! wv) return;
+
+  wv->name = wv->value = wv->key = (char *) 0xDEADBEEF;
+
+  if (wv->contents && (wv->contents != (widget_value*)1))
+    {
+      free_menubar_widget_value_tree (wv->contents);
+      wv->contents = (widget_value *) 0xDEADBEEF;
+    }
+  if (wv->next)
+    {
+      free_menubar_widget_value_tree (wv->next);
+      wv->next = (widget_value *) 0xDEADBEEF;
+    }
+  BLOCK_INPUT;
+  free_widget_value (wv);
+  UNBLOCK_INPUT;
+}
+
+/* Return a tree of widget_value structures for a menu bar item
+   whose event type is ITEM_KEY (with string ITEM_NAME)
+   and whose contents come from the list of keymaps MAPS.  */
+
+static widget_value *
+single_submenu (item_key, item_name, maps)
+     Lisp_Object item_key, item_name, maps;
+{
+  widget_value *wv, *prev_wv, *save_wv, *first_wv;
+  int i;
+  int submenu_depth = 0;
+  Lisp_Object length;
+  int len;
+  Lisp_Object *mapvec;
+  widget_value **submenu_stack;
+  int previous_items = menu_items_used;
+  int top_level_items = 0;
+
+  length = Flength (maps);
+  len = XINT (length);
+
+  /* Convert the list MAPS into a vector MAPVEC.  */
+  mapvec = (Lisp_Object *) alloca (len * sizeof (Lisp_Object));
+  for (i = 0; i < len; i++)
+    {
+      mapvec[i] = Fcar (maps);
+      maps = Fcdr (maps);
+    }
+
+  menu_items_n_panes = 0;
+
+  /* Loop over the given keymaps, making a pane for each map.
+     But don't make a pane that is empty--ignore that map instead.  */
+  for (i = 0; i < len; i++)
+    {
+      if (SYMBOLP (mapvec[i])
+	  || (CONSP (mapvec[i]) && !KEYMAPP (mapvec[i])))
+	{
+	  /* Here we have a command at top level in the menu bar
+	     as opposed to a submenu.  */
+	  top_level_items = 1;
+	  push_menu_pane (Qnil, Qnil);
+	  push_menu_item (item_name, Qt, item_key, mapvec[i],
+                          Qnil, Qnil, Qnil, Qnil);
+	}
+      else
+	single_keymap_panes (mapvec[i], item_name, item_key, 0, 10);
+    }
+
+  /* Create a tree of widget_value objects
+     representing the panes and their items.  */
+
+  submenu_stack
+    = (widget_value **) alloca (menu_items_used * sizeof (widget_value *));
+  wv = xmalloc_widget_value ();
+  wv->name = "menu";
+  wv->value = 0;
+  wv->enabled = 1;
+  wv->button_type = BUTTON_TYPE_NONE;
+  wv->help = Qnil;
+  first_wv = wv;
+  save_wv = 0;
+  prev_wv = 0;
+ 
+  /* Loop over all panes and items made during this call
+     and construct a tree of widget_value objects.
+     Ignore the panes and items made by previous calls to
+     single_submenu, even though those are also in menu_items.  */
+  i = previous_items;
+  while (i < menu_items_used)
+    {
+      if (EQ (XVECTOR (menu_items)->contents[i], Qnil))
+	{
+	  submenu_stack[submenu_depth++] = save_wv;
+	  save_wv = prev_wv;
+	  prev_wv = 0;
+	  i++;
+	}
+      else if (EQ (XVECTOR (menu_items)->contents[i], Qlambda))
+	{
+	  prev_wv = save_wv;
+	  save_wv = submenu_stack[--submenu_depth];
+	  i++;
+	}
+      else if (EQ (XVECTOR (menu_items)->contents[i], Qt)
+	       && submenu_depth != 0)
+	i += MENU_ITEMS_PANE_LENGTH;
+      /* Ignore a nil in the item list.
+	 It's meaningful only for dialog boxes.  */
+      else if (EQ (XVECTOR (menu_items)->contents[i], Qquote))
+	i += 1;
+      else if (EQ (XVECTOR (menu_items)->contents[i], Qt))
+	{
+	  /* Create a new pane.  */
+	  Lisp_Object pane_name, prefix;
+	  char *pane_string;
+
+	  pane_name = XVECTOR (menu_items)->contents[i + MENU_ITEMS_PANE_NAME];
+	  prefix = XVECTOR (menu_items)->contents[i + MENU_ITEMS_PANE_PREFIX];
+
+#ifndef HAVE_MULTILINGUAL_MENU
+	  if (STRINGP (pane_name) && STRING_MULTIBYTE (pane_name))
+	    {
+	      pane_name = ENCODE_SYSTEM (pane_name);
+	      AREF (menu_items, i + MENU_ITEMS_PANE_NAME) = pane_name;
+	    }
+#endif
+	  pane_string = (NILP (pane_name)
+			 ? "" : (char *) XSTRING (pane_name)->data);
+	  /* If there is just one top-level pane, put all its items directly
+	     under the top-level menu.  */
+	  if (menu_items_n_panes == 1)
+	    pane_string = "";
+
+	  /* If the pane has a meaningful name,
+	     make the pane a top-level menu item
+	     with its items as a submenu beneath it.  */
+	  if (strcmp (pane_string, ""))
+	    {
+	      wv = xmalloc_widget_value ();
+	      if (save_wv)
+		save_wv->next = wv;
+	      else
+		first_wv->contents = wv;
+	      wv->name = pane_string;
+	      /* Ignore the @ that means "separate pane".
+		 This is a kludge, but this isn't worth more time.  */
+	      if (!NILP (prefix) && wv->name[0] == '@')
+		wv->name++;
+	      wv->value = 0;
+	      wv->enabled = 1;
+	      wv->button_type = BUTTON_TYPE_NONE;
+	      wv->help = Qnil;
+	    }
+	  save_wv = wv;
+	  prev_wv = 0;
+	  i += MENU_ITEMS_PANE_LENGTH;
+	}
+      else
+	{
+	  /* Create a new item within current pane.  */
+	  Lisp_Object item_name, enable, descrip, def, type, selected;
+          Lisp_Object help;
+
+	  item_name = AREF (menu_items, i + MENU_ITEMS_ITEM_NAME);
+	  enable = AREF (menu_items, i + MENU_ITEMS_ITEM_ENABLE);
+	  descrip = AREF (menu_items, i + MENU_ITEMS_ITEM_EQUIV_KEY);
+	  def = AREF (menu_items, i + MENU_ITEMS_ITEM_DEFINITION);
+	  type = AREF (menu_items, i + MENU_ITEMS_ITEM_TYPE);
+	  selected = AREF (menu_items, i + MENU_ITEMS_ITEM_SELECTED);
+	  help = AREF (menu_items, i + MENU_ITEMS_ITEM_HELP);
+
+#ifndef HAVE_MULTILINGUAL_MENU
+	  if (STRING_MULTIBYTE (item_name))
+	    {
+	      item_name = ENCODE_SYSTEM (item_name);
+	      AREF (menu_items, i + MENU_ITEMS_ITEM_NAME) = item_name;
+	    }
+
+	  if (STRINGP (descrip) && STRING_MULTIBYTE (descrip))
+	    {
+	      descrip = ENCODE_SYSTEM (descrip);
+	      AREF (menu_items, i + MENU_ITEMS_ITEM_EQUIV_KEY) = descrip;
+	    }
+#endif /* not HAVE_MULTILINGUAL_MENU */
+
+	  wv = xmalloc_widget_value ();
+	  if (prev_wv) 
+	    prev_wv->next = wv;
+	  else
+	    save_wv->contents = wv;
+
+	  wv->name = (char *) XSTRING (item_name)->data;
+	  if (!NILP (descrip))
+	    wv->key = (char *) XSTRING (descrip)->data;
+	  wv->value = 0;
+	  /* The EMACS_INT cast avoids a warning.  There's no problem
+	     as long as pointers have enough bits to hold small integers.  */
+	  wv->call_data = (!NILP (def) ? (void *) (EMACS_INT) i : 0);
+	  wv->enabled = !NILP (enable);
+
+	  if (NILP (type))
+	    wv->button_type = BUTTON_TYPE_NONE;
+	  else if (EQ (type, QCradio))
+	    wv->button_type = BUTTON_TYPE_RADIO;
+	  else if (EQ (type, QCtoggle))
+	    wv->button_type = BUTTON_TYPE_TOGGLE;
+	  else
+	    abort ();
+
+	  wv->selected = !NILP (selected);
+	  if (!STRINGP (help))
+	    help = Qnil;
+
+	  wv->help = help;
+
+	  prev_wv = wv;
+
+	  i += MENU_ITEMS_ITEM_LENGTH;
+	}
+    }
+
+  /* If we have just one "menu item"
+     that was originally a button, return it by itself.  */
+  if (top_level_items && first_wv->contents && first_wv->contents->next == 0)
+    {
+      wv = first_wv->contents;
+      free_widget_value (first_wv);
+      return wv;
+    }
+
+  return first_wv;
+}
+
+/* Set the contents of the menubar widgets of frame F.
+   The argument FIRST_TIME is currently ignored;
+   it is set the first time this is called, from initialize_frame_menubar.  */
+
+void
+set_frame_menubar (f, first_time, deep_p)
+     FRAME_PTR f;
+     int first_time;
+     int deep_p;
+{
+  int menubar_widget = f->output_data.mac->menubar_widget;
+  Lisp_Object items;
+  widget_value *wv, *first_wv, *prev_wv = 0;
+  int i;
+
+  /* We must not change the menubar when actually in use.  */
+  if (f->output_data.mac->menubar_active)
+    return;
+
+  XSETFRAME (Vmenu_updating_frame, f);
+
+  if (! menubar_widget)
+    deep_p = 1;
+  else if (pending_menu_activation && !deep_p)
+    deep_p = 1;
+
+  wv = xmalloc_widget_value ();
+  wv->name = "menubar";
+  wv->value = 0;
+  wv->enabled = 1;
+  wv->button_type = BUTTON_TYPE_NONE;
+  wv->help = Qnil;
+  first_wv = wv;
+
+  if (deep_p)
+    {
+      /* Make a widget-value tree representing the entire menu trees.  */
+
+      struct buffer *prev = current_buffer;
+      Lisp_Object buffer;
+      int specpdl_count = specpdl_ptr - specpdl;
+      int previous_menu_items_used = f->menu_bar_items_used;
+      Lisp_Object *previous_items
+	= (Lisp_Object *) alloca (previous_menu_items_used
+				  * sizeof (Lisp_Object));
+
+      /* If we are making a new widget, its contents are empty,
+	 do always reinitialize them.  */
+      if (! menubar_widget)
+	previous_menu_items_used = 0;
+
+      buffer = XWINDOW (FRAME_SELECTED_WINDOW (f))->buffer;
+      specbind (Qinhibit_quit, Qt);
+      /* Don't let the debugger step into this code
+	 because it is not reentrant.  */
+      specbind (Qdebug_on_next_call, Qnil);
+
+      record_unwind_protect (Fset_match_data, Fmatch_data (Qnil, Qnil));
+      if (NILP (Voverriding_local_map_menu_flag))
+	{
+	  specbind (Qoverriding_terminal_local_map, Qnil);
+	  specbind (Qoverriding_local_map, Qnil);
+	}
+
+      set_buffer_internal_1 (XBUFFER (buffer));
+
+      /* Run the Lucid hook.  */
+      safe_run_hooks (Qactivate_menubar_hook);
+      /* If it has changed current-menubar from previous value,
+	 really recompute the menubar from the value.  */
+      if (! NILP (Vlucid_menu_bar_dirty_flag))
+	call0 (Qrecompute_lucid_menubar);
+      safe_run_hooks (Qmenu_bar_update_hook);
+      FRAME_MENU_BAR_ITEMS (f) = menu_bar_items (FRAME_MENU_BAR_ITEMS (f));
+
+      items = FRAME_MENU_BAR_ITEMS (f);
+
+      inhibit_garbage_collection ();
+
+      /* Save the frame's previous menu bar contents data.  */
+      if (previous_menu_items_used)
+	bcopy (XVECTOR (f->menu_bar_vector)->contents, previous_items,
+	       previous_menu_items_used * sizeof (Lisp_Object));
+
+      /* Fill in the current menu bar contents.  */
+      menu_items = f->menu_bar_vector;
+      menu_items_allocated = VECTORP (menu_items) ? ASIZE (menu_items) : 0;
+      init_menu_items ();
+      for (i = 0; i < XVECTOR (items)->size; i += 4)
+	{
+	  Lisp_Object key, string, maps;
+
+	  key = XVECTOR (items)->contents[i];
+	  string = XVECTOR (items)->contents[i + 1];
+	  maps = XVECTOR (items)->contents[i + 2];
+	  if (NILP (string))
+	    break;
+
+	  wv = single_submenu (key, string, maps);
+	  if (prev_wv) 
+	    prev_wv->next = wv;
+	  else
+	    first_wv->contents = wv;
+	  /* Don't set wv->name here; GC during the loop might relocate it.  */
+	  wv->enabled = 1;
+	  wv->button_type = BUTTON_TYPE_NONE;
+	  prev_wv = wv;
+	}
+
+      finish_menu_items ();
+
+      set_buffer_internal_1 (prev);
+      unbind_to (specpdl_count, Qnil);
+
+      /* If there has been no change in the Lisp-level contents
+	 of the menu bar, skip redisplaying it.  Just exit.  */
+
+      for (i = 0; i < previous_menu_items_used; i++)
+	if (menu_items_used == i
+	    || (!Fequal (previous_items[i], XVECTOR (menu_items)->contents[i])))
+	  break;
+      if (i == menu_items_used && i == previous_menu_items_used && i != 0)
+	{
+	  free_menubar_widget_value_tree (first_wv);
+	  menu_items = Qnil;
+
+	  return;
+	}
+
+      /* Now GC cannot happen during the lifetime of the widget_value,
+	 so it's safe to store data from a Lisp_String, as long as
+	 local copies are made when the actual menu is created.
+	 Windows takes care of this for normal string items, but
+	 not for owner-drawn items or additional item-info.  */
+      wv = first_wv->contents;
+      for (i = 0; i < XVECTOR (items)->size; i += 4)
+	{
+	  Lisp_Object string;
+	  string = XVECTOR (items)->contents[i + 1];
+	  if (NILP (string))
+	    break;
+	  wv->name = (char *) XSTRING (string)->data;
+	  wv = wv->next;
+	}
+
+      f->menu_bar_vector = menu_items;
+      f->menu_bar_items_used = menu_items_used;
+      menu_items = Qnil;
+    }
+  else
+    {
+      /* Make a widget-value tree containing
+	 just the top level menu bar strings.  */
+
+      items = FRAME_MENU_BAR_ITEMS (f);
+      for (i = 0; i < XVECTOR (items)->size; i += 4)
+	{
+	  Lisp_Object string;
+
+	  string = XVECTOR (items)->contents[i + 1];
+	  if (NILP (string))
+	    break;
+
+	  wv = xmalloc_widget_value ();
+	  wv->name = (char *) XSTRING (string)->data;
+	  wv->value = 0;
+	  wv->enabled = 1;
+	  wv->button_type = BUTTON_TYPE_NONE;
+	  wv->help = Qnil;
+	  /* This prevents lwlib from assuming this
+	     menu item is really supposed to be empty.  */
+	  /* The EMACS_INT cast avoids a warning.
+	     This value just has to be different from small integers.  */
+	  wv->call_data = (void *) (EMACS_INT) (-1);
+
+	  if (prev_wv) 
+	    prev_wv->next = wv;
+	  else
+	    first_wv->contents = wv;
+	  prev_wv = wv;
+	}
+
+      /* Forget what we thought we knew about what is in the
+	 detailed contents of the menu bar menus.
+	 Changing the top level always destroys the contents.  */
+      f->menu_bar_items_used = 0;
+    }
+
+  /* Create or update the menu bar widget.  */
+
+  BLOCK_INPUT;
+
+  /* Non-null value to indicate menubar has already been "created".  */
+  f->output_data.mac->menubar_widget = 1;
+
+  {
+    int i = MIN_MENU_ID;
+    MenuHandle menu = GetMenuHandle (i);
+    while (menu != NULL)
+      {
+	DeleteMenu (i);
+	DisposeMenu (menu);
+	menu = GetMenuHandle (++i);
+      }
+    
+    i = MIN_SUBMENU_ID;
+    menu = GetMenuHandle (i);
+    while (menu != NULL)
+      {
+	DeleteMenu (i);
+	DisposeMenu (menu);
+	menu = GetMenuHandle (++i);
+      }
+  }
+
+  fill_menubar (first_wv->contents);
+  
+  DrawMenuBar ();
+  
+  free_menubar_widget_value_tree (first_wv);
+
+  UNBLOCK_INPUT;
+}
+
+/* Called from Fx_create_frame to create the initial menubar of a frame
+   before it is mapped, so that the window is mapped with the menubar already
+   there instead of us tacking it on later and thrashing the window after it
+   is visible.  */
+
+void
+initialize_frame_menubar (f)
+     FRAME_PTR f;
+{
+  /* This function is called before the first chance to redisplay
+     the frame.  It has to be, so the frame will have the right size.  */
+  FRAME_MENU_BAR_ITEMS (f) = menu_bar_items (FRAME_MENU_BAR_ITEMS (f));
+  set_frame_menubar (f, 1, 1);
+}
+
+/* Get rid of the menu bar of frame F, and free its storage.
+   This is used when deleting a frame, and when turning off the menu bar.  */
+
+void
+free_frame_menubar (f)
+     FRAME_PTR f;
+{
+  f->output_data.mac->menubar_widget = NULL;
+}
+
+
+/* mac_menu_show actually displays a menu using the panes and items in
+   menu_items and returns the value selected from it; we assume input
+   is blocked by the caller.  */
+
+/* F is the frame the menu is for.
+   X and Y are the frame-relative specified position,
+   relative to the inside upper left corner of the frame F.
+   FOR_CLICK is nonzero if this menu was invoked for a mouse click.
+   KEYMAPS is 1 if this menu was specified with keymaps;
+    in that case, we return a list containing the chosen item's value
+    and perhaps also the pane's prefix.
+   TITLE is the specified menu title.
+   ERROR is a place to store an error message string in case of failure.
+   (We return nil on failure, but the value doesn't actually matter.)  */
+
+static Lisp_Object
+mac_menu_show (f, x, y, for_click, keymaps, title, error)
+     FRAME_PTR f;
+     int x;
+     int y;
+     int for_click;
+     int keymaps;
+     Lisp_Object title;
+     char **error;
+{
+  int i;
+  int menu_item_selection;
+  MenuHandle menu;
+  Point pos;
+  widget_value *wv, *save_wv = 0, *first_wv = 0, *prev_wv = 0;
+  widget_value **submenu_stack
+    = (widget_value **) alloca (menu_items_used * sizeof (widget_value *));
+  Lisp_Object *subprefix_stack
+    = (Lisp_Object *) alloca (menu_items_used * sizeof (Lisp_Object));
+  int submenu_depth = 0;
+  int first_pane;
+
+  *error = NULL;
+
+  if (menu_items_used <= MENU_ITEMS_PANE_LENGTH)
+    {
+      *error = "Empty menu";
+      return Qnil;
+    }
+
+  /* Create a tree of widget_value objects
+     representing the panes and their items.  */
+  wv = xmalloc_widget_value ();
+  wv->name = "menu";
+  wv->value = 0;
+  wv->enabled = 1;
+  wv->button_type = BUTTON_TYPE_NONE;
+  wv->help = Qnil;
+  first_wv = wv;
+  first_pane = 1;
+ 
+  /* Loop over all panes and items, filling in the tree.  */
+  i = 0;
+  while (i < menu_items_used)
+    {
+      if (EQ (XVECTOR (menu_items)->contents[i], Qnil))
+	{
+	  submenu_stack[submenu_depth++] = save_wv;
+	  save_wv = prev_wv;
+	  prev_wv = 0;
+	  first_pane = 1;
+	  i++;
+	}
+      else if (EQ (XVECTOR (menu_items)->contents[i], Qlambda))
+	{
+	  prev_wv = save_wv;
+	  save_wv = submenu_stack[--submenu_depth];
+	  first_pane = 0;
+	  i++;
+	}
+      else if (EQ (XVECTOR (menu_items)->contents[i], Qt)
+	       && submenu_depth != 0)
+	i += MENU_ITEMS_PANE_LENGTH;
+      /* Ignore a nil in the item list.
+	 It's meaningful only for dialog boxes.  */
+      else if (EQ (XVECTOR (menu_items)->contents[i], Qquote))
+	i += 1;
+      else if (EQ (XVECTOR (menu_items)->contents[i], Qt))
+	{
+	  /* Create a new pane.  */
+	  Lisp_Object pane_name, prefix;
+	  char *pane_string;
+	  pane_name = AREF (menu_items, i + MENU_ITEMS_PANE_NAME);
+	  prefix = AREF (menu_items, i + MENU_ITEMS_PANE_PREFIX);
+#ifndef HAVE_MULTILINGUAL_MENU
+	  if (STRINGP (pane_name) && STRING_MULTIBYTE (pane_name))
+	    {
+	      pane_name = ENCODE_SYSTEM (pane_name);
+	      AREF (menu_items, i + MENU_ITEMS_PANE_NAME) = pane_name;
+	    }
+#endif
+	  pane_string = (NILP (pane_name)
+			 ? "" : (char *) XSTRING (pane_name)->data);
+	  /* If there is just one top-level pane, put all its items directly
+	     under the top-level menu.  */
+	  if (menu_items_n_panes == 1)
+	    pane_string = "";
+
+	  /* If the pane has a meaningful name,
+	     make the pane a top-level menu item
+	     with its items as a submenu beneath it.  */
+	  if (!keymaps && strcmp (pane_string, ""))
+	    {
+	      wv = xmalloc_widget_value ();
+	      if (save_wv)
+		save_wv->next = wv;
+	      else
+		first_wv->contents = wv;
+	      wv->name = pane_string;
+	      if (keymaps && !NILP (prefix))
+		wv->name++;
+	      wv->value = 0;
+	      wv->enabled = 1;
+	      wv->button_type = BUTTON_TYPE_NONE;
+	      wv->help = Qnil;
+	      save_wv = wv;
+	      prev_wv = 0;
+	    }
+	  else if (first_pane)
+	    {
+	      save_wv = wv;
+	      prev_wv = 0;
+	    }
+	  first_pane = 0;
+	  i += MENU_ITEMS_PANE_LENGTH;
+	}
+      else
+	{
+	  /* Create a new item within current pane.  */
+	  Lisp_Object item_name, enable, descrip, def, type, selected, help;
+
+	  item_name = AREF (menu_items, i + MENU_ITEMS_ITEM_NAME);
+	  enable = AREF (menu_items, i + MENU_ITEMS_ITEM_ENABLE);
+	  descrip = AREF (menu_items, i + MENU_ITEMS_ITEM_EQUIV_KEY);
+	  def = AREF (menu_items, i + MENU_ITEMS_ITEM_DEFINITION);
+	  type = AREF (menu_items, i + MENU_ITEMS_ITEM_TYPE);
+	  selected = AREF (menu_items, i + MENU_ITEMS_ITEM_SELECTED);
+          help = AREF (menu_items, i + MENU_ITEMS_ITEM_HELP);
+
+#ifndef HAVE_MULTILINGUAL_MENU
+          if (STRINGP (item_name) && STRING_MULTIBYTE (item_name))
+	    {
+	      item_name = ENCODE_SYSTEM (item_name);
+	      AREF (menu_items, i + MENU_ITEMS_ITEM_NAME) = item_name;
+	    }
+          if (STRINGP (descrip) && STRING_MULTIBYTE (descrip))
+            {
+	      descrip = ENCODE_SYSTEM (descrip);
+	      AREF (menu_items, i + MENU_ITEMS_ITEM_EQUIV_KEY) = descrip;
+	    }
+#endif /* not HAVE_MULTILINGUAL_MENU */
+
+	  wv = xmalloc_widget_value ();
+	  if (prev_wv) 
+	    prev_wv->next = wv;
+	  else 
+	    save_wv->contents = wv;
+	  wv->name = (char *) XSTRING (item_name)->data;
+	  if (!NILP (descrip))
+	    wv->key = (char *) XSTRING (descrip)->data;
+	  wv->value = 0;
+	  /* Use the contents index as call_data, since we are
+             restricted to 16-bits.  */
+	  wv->call_data = !NILP (def) ? (void *) (EMACS_INT) i : 0;
+	  wv->enabled = !NILP (enable);
+
+	  if (NILP (type))
+	    wv->button_type = BUTTON_TYPE_NONE;
+	  else if (EQ (type, QCtoggle))
+	    wv->button_type = BUTTON_TYPE_TOGGLE;
+	  else if (EQ (type, QCradio))
+	    wv->button_type = BUTTON_TYPE_RADIO;
+	  else
+	    abort ();
+
+	  wv->selected = !NILP (selected);
+          if (!STRINGP (help))
+	    help = Qnil;
+
+	  wv->help = help;
+
+	  prev_wv = wv;
+
+	  i += MENU_ITEMS_ITEM_LENGTH;
+	}
+    }
+
+  /* Deal with the title, if it is non-nil.  */
+  if (!NILP (title))
+    {
+      widget_value *wv_title = xmalloc_widget_value ();
+      widget_value *wv_sep = xmalloc_widget_value ();
+
+      /* Maybe replace this separator with a bitmap or owner-draw item
+	 so that it looks better.  Having two separators looks odd.  */
+      wv_sep->name = "--";
+      wv_sep->next = first_wv->contents;
+      wv_sep->help = Qnil;
+
+#ifndef HAVE_MULTILINGUAL_MENU
+      if (STRING_MULTIBYTE (title))
+	title = ENCODE_SYSTEM (title);
+#endif
+      wv_title->name = (char *) XSTRING (title)->data;
+      wv_title->enabled = TRUE;
+      wv_title->title = TRUE;
+      wv_title->button_type = BUTTON_TYPE_NONE;
+      wv_title->help = Qnil;
+      wv_title->next = wv_sep;
+      first_wv->contents = wv_title;
+    }
+
+  /* Actually create the menu.  */
+  menu = NewMenu (POPUP_SUBMENU_ID, "\p");
+  fill_submenu (menu, first_wv->contents, 0);
+
+  /* Adjust coordinates to be root-window-relative.  */
+  pos.h = x;
+  pos.v = y;
+
+#if TARGET_API_MAC_CARBON
+  SetPort (GetWindowPort (FRAME_MAC_WINDOW (f)));
+#else
+  SetPort (FRAME_MAC_WINDOW (f));
+#endif
+
+  LocalToGlobal (&pos);
+
+  /* No selection has been chosen yet.  */
+  menu_item_selection = 0;
+
+  InsertMenu (menu, -1);
+
+  /* Display the menu.  */
+  menu_item_selection = LoWord (PopUpMenuSelect (menu, pos.v, pos.h, 0));
+
+  DeleteMenu (POPUP_SUBMENU_ID);
+  
+#if 0
+  /* Clean up extraneous mouse events which might have been generated
+     during the call.  */
+  discard_mouse_events ();
+#endif
+
+  /* Free the widget_value objects we used to specify the
+     contents.  */
+  free_menubar_widget_value_tree (first_wv);
+
+  DisposeMenu (menu);
+
+  /* Find the selected item, and its pane, to return
+     the proper value.  */
+  if (menu_item_selection != 0)
+    {
+      Lisp_Object prefix, entry;
+
+      prefix = entry = Qnil;
+      i = 0;
+      while (i < menu_items_used)
+	{
+	  if (EQ (XVECTOR (menu_items)->contents[i], Qnil))
+	    {
+	      subprefix_stack[submenu_depth++] = prefix;
+	      prefix = entry;
+	      i++;
+	    }
+	  else if (EQ (XVECTOR (menu_items)->contents[i], Qlambda))
+	    {
+	      prefix = subprefix_stack[--submenu_depth];
+	      i++;
+	    }
+	  else if (EQ (XVECTOR (menu_items)->contents[i], Qt))
+	    {
+	      prefix
+		= XVECTOR (menu_items)->contents[i + MENU_ITEMS_PANE_PREFIX];
+	      i += MENU_ITEMS_PANE_LENGTH;
+	    }
+	  /* Ignore a nil in the item list.
+	     It's meaningful only for dialog boxes.  */
+	  else if (EQ (XVECTOR (menu_items)->contents[i], Qquote))
+	    i += 1;
+	  else
+	    {
+	      entry
+		= XVECTOR (menu_items)->contents[i + MENU_ITEMS_ITEM_VALUE];
+	      if (menu_item_selection == i)
+		{
+		  if (keymaps != 0)
+		    {
+		      int j;
+
+		      entry = Fcons (entry, Qnil);
+		      if (!NILP (prefix))
+			entry = Fcons (prefix, entry);
+		      for (j = submenu_depth - 1; j >= 0; j--)
+			if (!NILP (subprefix_stack[j]))
+			  entry = Fcons (subprefix_stack[j], entry);
+		    }
+		  return entry;
+		}
+	      i += MENU_ITEMS_ITEM_LENGTH;
+	    }
+	}
+    }
+
+  return Qnil;
+}
+
+
+#ifdef HAVE_DIALOGS
+/* Construct native Mac OS menubar based on widget_value tree.  */
+
+static int
+mac_dialog (widget_value *wv)
+{
+  char *dialog_name;
+  char *prompt;
+  char **button_labels;
+  UInt32 *ref_cons;
+  int nb_buttons;
+  int left_count;
+  int i;
+  int dialog_width;
+  Rect rect;
+  WindowPtr window_ptr;
+  ControlHandle ch;
+  int left;
+  EventRecord event_record;
+  SInt16 part_code;
+  int control_part_code;
+  Point mouse;
+            
+  dialog_name = wv->name;
+  nb_buttons = dialog_name[1] - '0';
+  left_count = nb_buttons - (dialog_name[4] - '0');
+  button_labels = (char **) alloca (sizeof (char *) * nb_buttons);
+  ref_cons = (UInt32 *) alloca (sizeof (UInt32) * nb_buttons);
+  
+  wv = wv->contents;
+  prompt = (char *) alloca (strlen (wv->value) + 1);
+  strcpy (prompt, wv->value);
+  c2pstr (prompt);
+
+  wv = wv->next;
+  for (i = 0; i < nb_buttons; i++)
+    {
+      button_labels[i] = wv->value;
+      button_labels[i] = (char *) alloca (strlen (wv->value) + 1);
+      strcpy (button_labels[i], wv->value);
+      c2pstr (button_labels[i]);
+      ref_cons[i] = (UInt32) wv->call_data;
+      wv = wv->next;
+    }
+
+  window_ptr = GetNewCWindow (DIALOG_WINDOW_RESOURCE, NULL, (WindowPtr) -1);
+
+#if TARGET_API_MAC_CARBON
+  SetPort (GetWindowPort (window_ptr));
+#else
+  SetPort (window_ptr);
+#endif
+  
+  TextFont (0);
+  /* Left and right margins in the dialog are 13 pixels each.*/
+  dialog_width = 14;
+  /* Calculate width of dialog box: 8 pixels on each side of the text
+     label in each button, 12 pixels between buttons.  */
+  for (i = 0; i < nb_buttons; i++)
+    dialog_width +=  StringWidth (button_labels[i]) + 16 + 12;
+
+  if (left_count != 0 && nb_buttons - left_count != 0)
+    dialog_width += 12;
+
+  dialog_width = max (dialog_width, StringWidth (prompt) + 26);
+
+  SizeWindow (window_ptr, dialog_width, 78, 0);
+  ShowWindow (window_ptr);
+
+#if TARGET_API_MAC_CARBON
+  SetPort (GetWindowPort (window_ptr));
+#else
+  SetPort (window_ptr);
+#endif
+  
+  TextFont (0);
+
+  MoveTo (13, 29);
+  DrawString (prompt);
+
+  left = 13;
+  for (i = 0; i < nb_buttons; i++)
+    {
+      int button_width = StringWidth (button_labels[i]) + 16;
+      SetRect (&rect, left, 45, left + button_width, 65);
+      ch = NewControl (window_ptr, &rect, button_labels[i], 1, 0, 0, 0,
+                       kControlPushButtonProc, ref_cons[i]);
+      left += button_width + 12;
+      if (i == left_count - 1)
+        left += 12;
+    }
+
+  i = 0;
+  while (!i)
+    {
+      if (WaitNextEvent (mDownMask, &event_record, 10, NULL))
+        if (event_record.what == mouseDown)
+          {
+            part_code = FindWindow (event_record.where, &window_ptr);
+            if (part_code == inContent)
+              {
+                mouse = event_record.where;
+                GlobalToLocal (&mouse);
+                control_part_code = FindControl (mouse, window_ptr, &ch);
+                if (control_part_code == kControlButtonPart)
+                  if (TrackControl (ch, mouse, NULL))
+                    i = GetControlReference (ch);
+              }
+          }
+    }
+
+  DisposeWindow (window_ptr);
+  
+  return i;
+}
+
+static char * button_names [] = {
+  "button1", "button2", "button3", "button4", "button5",
+  "button6", "button7", "button8", "button9", "button10" };
+
+static Lisp_Object
+mac_dialog_show (f, keymaps, title, error)
+     FRAME_PTR f;
+     int keymaps;
+     Lisp_Object title;
+     char **error;
+{
+  int i, nb_buttons=0;
+  char dialog_name[6];
+  int menu_item_selection;
+
+  widget_value *wv, *first_wv = 0, *prev_wv = 0;
+
+  /* Number of elements seen so far, before boundary.  */
+  int left_count = 0;
+  /* 1 means we've seen the boundary between left-hand elts and right-hand.  */
+  int boundary_seen = 0;
+
+  *error = NULL;
+
+  if (menu_items_n_panes > 1)
+    {
+      *error = "Multiple panes in dialog box";
+      return Qnil;
+    }
+
+  /* Create a tree of widget_value objects
+     representing the text label and buttons.  */
+  {
+    Lisp_Object pane_name, prefix;
+    char *pane_string;
+    pane_name = XVECTOR (menu_items)->contents[MENU_ITEMS_PANE_NAME];
+    prefix = XVECTOR (menu_items)->contents[MENU_ITEMS_PANE_PREFIX];
+    pane_string = (NILP (pane_name)
+		   ? "" : (char *) XSTRING (pane_name)->data);  
+    prev_wv = xmalloc_widget_value ();
+    prev_wv->value = pane_string;
+    if (keymaps && !NILP (prefix))
+      prev_wv->name++;
+    prev_wv->enabled = 1;
+    prev_wv->name = "message";
+    prev_wv->help = Qnil;
+    first_wv = prev_wv;
+ 
+    /* Loop over all panes and items, filling in the tree.  */
+    i = MENU_ITEMS_PANE_LENGTH;
+    while (i < menu_items_used)
+      {
+	
+	/* Create a new item within current pane.  */
+	Lisp_Object item_name, enable, descrip, help;
+
+	item_name = XVECTOR (menu_items)->contents[i + MENU_ITEMS_ITEM_NAME];
+	enable = XVECTOR (menu_items)->contents[i + MENU_ITEMS_ITEM_ENABLE];
+	descrip
+	  = XVECTOR (menu_items)->contents[i + MENU_ITEMS_ITEM_EQUIV_KEY];
+        help = XVECTOR (menu_items)->contents[i + MENU_ITEMS_ITEM_HELP];
+	
+	if (NILP (item_name))
+	  {
+	    free_menubar_widget_value_tree (first_wv);
+	    *error = "Submenu in dialog items";
+	    return Qnil;
+	  }
+	if (EQ (item_name, Qquote))
+	  {
+	    /* This is the boundary between left-side elts
+	       and right-side elts.  Stop incrementing right_count.  */
+	    boundary_seen = 1;
+	    i++;
+	    continue;
+	  }
+	if (nb_buttons >= 9)
+	  {
+	    free_menubar_widget_value_tree (first_wv);
+	    *error = "Too many dialog items";
+	    return Qnil;
+	  }
+
+	wv = xmalloc_widget_value ();
+	prev_wv->next = wv;
+	wv->name = (char *) button_names[nb_buttons];
+	if (!NILP (descrip))
+	  wv->key = (char *) XSTRING (descrip)->data;
+	wv->value = (char *) XSTRING (item_name)->data;
+	wv->call_data = (void *) i;
+	  /* menu item is identified by its index in menu_items table */
+	wv->enabled = !NILP (enable);
+	wv->help = Qnil;
+	prev_wv = wv;
+
+	if (! boundary_seen)
+	  left_count++;
+
+	nb_buttons++;
+	i += MENU_ITEMS_ITEM_LENGTH;
+      }
+
+    /* If the boundary was not specified,
+       by default put half on the left and half on the right.  */
+    if (! boundary_seen)
+      left_count = nb_buttons - nb_buttons / 2;
+
+    wv = xmalloc_widget_value ();
+    wv->name = dialog_name;
+    wv->help = Qnil;
+
+    /* Dialog boxes use a really stupid name encoding
+       which specifies how many buttons to use
+       and how many buttons are on the right.
+       The Q means something also.  */
+    dialog_name[0] = 'Q';
+    dialog_name[1] = '0' + nb_buttons;
+    dialog_name[2] = 'B';
+    dialog_name[3] = 'R';
+    /* Number of buttons to put on the right.  */
+    dialog_name[4] = '0' + nb_buttons - left_count;
+    dialog_name[5] = 0;
+    wv->contents = first_wv;
+    first_wv = wv;
+  }
+
+  /* Actually create the dialog.  */
+#ifdef HAVE_DIALOGS
+  menu_item_selection = mac_dialog (first_wv);
+#else
+  menu_item_selection = 0;
+#endif
+
+  /* Free the widget_value objects we used to specify the contents.  */
+  free_menubar_widget_value_tree (first_wv);
+
+  /* Find the selected item, and its pane, to return the proper
+     value.  */
+  if (menu_item_selection != 0)
+    {
+      Lisp_Object prefix;
+
+      prefix = Qnil;
+      i = 0;
+      while (i < menu_items_used)
+	{
+	  Lisp_Object entry;
+
+	  if (EQ (XVECTOR (menu_items)->contents[i], Qt))
+	    {
+	      prefix
+		= XVECTOR (menu_items)->contents[i + MENU_ITEMS_PANE_PREFIX];
+	      i += MENU_ITEMS_PANE_LENGTH;
+	    }
+	  else
+	    {
+	      entry
+		= XVECTOR (menu_items)->contents[i + MENU_ITEMS_ITEM_VALUE];
+	      if (menu_item_selection == i)
+		{
+		  if (keymaps != 0)
+		    {
+		      entry = Fcons (entry, Qnil);
+		      if (!NILP (prefix))
+			entry = Fcons (prefix, entry);
+		    }
+		  return entry;
+		}
+	      i += MENU_ITEMS_ITEM_LENGTH;
+	    }
+	}
+    }
+
+  return Qnil;
+}
+#endif  /* HAVE_DIALOGS  */
+
+
+/* Is this item a separator? */
+static int
+name_is_separator (name)
+     char *name;
+{
+  char *start = name;
+
+  /* Check if name string consists of only dashes ('-').  */
+  while (*name == '-') name++;
+  /* Separators can also be of the form "--:TripleSuperMegaEtched"
+     or "--deep-shadow".  We don't implement them yet, se we just treat
+     them like normal separators.  */
+  return (*name == '\0' || start + 2 == name);
+}
+
+static void
+add_menu_item (MenuHandle menu, widget_value *wv, int submenu, int indent,
+	       int force_disable)
+{
+  Str255 item_name;
+  int pos, i;
+
+  if (name_is_separator (wv->name))
+    AppendMenu (menu, "\p-");
+  else 
+    {
+      AppendMenu (menu, "\pX");
+      
+#if TARGET_API_MAC_CARBON
+      pos = CountMenuItems (menu);
+#else
+      pos = CountMItems (menu);
+#endif
+
+      strcpy (item_name, "");
+      for (i = 0; i < indent; i++)
+        strcat (item_name, "    ");
+      strcat (item_name, wv->name);
+      if (wv->key != NULL)
+	{
+	  strcat (item_name, " ");
+	  strcat (item_name, wv->key);
+	}
+      c2pstr (item_name);
+      SetMenuItemText (menu, pos, item_name);
+
+      if (wv->enabled && !force_disable)
+#if TARGET_API_MAC_CARBON
+        EnableMenuItem (menu, pos);
+#else
+        EnableItem (menu, pos);
+#endif
+      else
+#if TARGET_API_MAC_CARBON
+        DisableMenuItem (menu, pos);
+#else
+        DisableItem (menu, pos);
+#endif
+
+      /* Draw radio buttons and tickboxes. */
+      {
+      if (wv->selected && (wv->button_type == BUTTON_TYPE_TOGGLE ||
+                           wv->button_type == BUTTON_TYPE_RADIO))
+	SetItemMark (menu, pos, checkMark);
+      else
+	SetItemMark (menu, pos, noMark);
+      }
+    }
+
+  SetMenuItemRefCon (menu, pos, (UInt32) wv->call_data);
+
+  if (submenu != NULL)
+    SetMenuItemHierarchicalID (menu, pos, submenu);
+}
+
+static int submenu_id;
+  
+/* Construct native Mac OS menubar based on widget_value tree.  */
+
+static void
+fill_submenu (MenuHandle menu, widget_value *wv, int indent)
+{
+  for ( ; wv != NULL; wv = wv->next)
+    if (wv->contents)
+      {
+        add_menu_item (menu, wv, NULL, indent, 1);
+        
+        fill_submenu (menu, wv->contents, indent + 1);
+      }
+    else
+      add_menu_item (menu, wv, NULL, indent, 0);
+}
+
+
+/* Construct native Mac OS menu based on widget_value tree.  */
+
+static void
+fill_menu (MenuHandle menu, widget_value *wv)
+{
+  for ( ; wv != NULL; wv = wv->next)
+    if (wv->contents)
+      {
+        MenuHandle submenu = NewMenu (submenu_id, "\pX");
+        fill_submenu (submenu, wv->contents, 0);
+        InsertMenu (submenu, -1);
+        add_menu_item (menu, wv, submenu_id, 0, 0);
+        submenu_id++;
+      }
+    else
+      add_menu_item (menu, wv, NULL, 0, 0);
+}
+
+/* Construct native Mac OS menubar based on widget_value tree.  */
+
+static void
+fill_menubar (widget_value *wv)
+{
+  int id;
+
+  submenu_id  = MIN_SUBMENU_ID;
+
+  for (id = MIN_MENU_ID; wv != NULL; wv = wv->next, id++)
+    {
+      MenuHandle menu;
+      Str255 title;
+        
+      strcpy (title, wv->name);
+      c2pstr (title);
+      menu = NewMenu (id, title);
+
+      if (wv->contents)
+        fill_menu (menu, wv->contents);
+      
+      InsertMenu (menu, 0);
+    }
+}
+
+#endif /* HAVE_MENUS */
+
+
+void
+syms_of_macmenu ()
+{
+  staticpro (&menu_items);
+  menu_items = Qnil;
+
+  Qdebug_on_next_call = intern ("debug-on-next-call");
+  staticpro (&Qdebug_on_next_call);
+
+  DEFVAR_LISP ("menu-updating-frame", &Vmenu_updating_frame,
+	       doc: /* Frame for which we are updating a menu.
+The enable predicate for a menu command should check this variable.  */);
+  Vmenu_updating_frame = Qnil;
+
+  defsubr (&Sx_popup_menu);
+#ifdef HAVE_MENUS
+  defsubr (&Sx_popup_dialog);
+#endif
+}