Widely used frame validity and checking functions.

* frame.h (decode_live_frame, decode_any_frame): Add prototypes.
* frame.c (decode_live_frame, decode_any_frame): New functions.
(delete_frame, Fredirect_frame_focus, Fframe_parameters)
(Fframe_parameter, Fframe_char_height, Fframe_char_width)
(Fframe_pixel_height, Fframe_pixel_width, Ftool_bar_pixel_width)
(Fframe_pointer_visible_p): Use decode_any_frame.
(Fmake_frame_visible, Fmake_frame_invisible, Ficonify_frame)
(Fraise_frame, Flower_frame, Fmodify_frame_parameters)
(Fset_frame_height, Fset_frame_width): Use decode_live_frame.
(Fframe_focus): Likewise.  Allow zero number of arguments.
Adjust docstring.
(frame_buffer_list, frame_buffer_predicate): Remove.
* lisp.h (frame_buffer_predicate): Remove prototype.
* buffer.c (Fother_buffer): Use decode_any_frame.
* xdisp.c (Ftool_bar_lines_needed): Likewise.
* xfaces.c (Fcolor_gray_p, Fcolor_supported_p): Likewise.
* font.c (Ffont_face_attributes, Ffont_family_list, Fopen_font)
(Fclose_font, Ffont_info): Use decode_live_frame.
* fontset.c (check_fontset_name): Likewise.
* terminal.c (Fframe_terminal): Likewise.
* w32fns.c (check_x_frame): Likewise.
* window.c (Fminibuffer_window, Fwindow_at)
(Fcurrent_window_configuration): Likewise.
(Frun_window_configuration_change_hook, Fwindow_resize_apply):
Likewise.  Allow zero number of arguments.  Adjust docstring.
* dispnew.c (Fredraw_frame): Likewise.
* xfaces.c (frame_or_selected_frame): Remove.
(Fx_list_fonts, Finternal_get_lisp_face_attribute, Fface_font)
(Finternal_lisp_face_equal_p, Finternal_lisp_face_empty_p)
(Fframe_face_alist): Use decode_live_frame.
* xfns.c (check_x_frame): Likewise.

14 files changed, 172 insertions, 348 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 1daeb7bc0b6..0a277a0d67b 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,5 +1,40 @@
 2012-11-06  Dmitry Antipov  <dmantipov@yandex.ru>
 
+	Widely used frame validity and checking functions.
+	* frame.h (decode_live_frame, decode_any_frame): Add prototypes.
+	* frame.c (decode_live_frame, decode_any_frame): New functions.
+	(delete_frame, Fredirect_frame_focus, Fframe_parameters)
+	(Fframe_parameter, Fframe_char_height, Fframe_char_width)
+	(Fframe_pixel_height, Fframe_pixel_width, Ftool_bar_pixel_width)
+	(Fframe_pointer_visible_p): Use decode_any_frame.
+	(Fmake_frame_visible, Fmake_frame_invisible, Ficonify_frame)
+	(Fraise_frame, Flower_frame, Fmodify_frame_parameters)
+	(Fset_frame_height, Fset_frame_width): Use decode_live_frame.
+	(Fframe_focus): Likewise.  Allow zero number of arguments.
+	Adjust docstring.
+	(frame_buffer_list, frame_buffer_predicate): Remove.
+	* lisp.h (frame_buffer_predicate): Remove prototype.
+	* buffer.c (Fother_buffer): Use decode_any_frame.
+	* xdisp.c (Ftool_bar_lines_needed): Likewise.
+	* xfaces.c (Fcolor_gray_p, Fcolor_supported_p): Likewise.
+	* font.c (Ffont_face_attributes, Ffont_family_list, Fopen_font)
+	(Fclose_font, Ffont_info): Use decode_live_frame.
+	* fontset.c (check_fontset_name): Likewise.
+	* terminal.c (Fframe_terminal): Likewise.
+	* w32fns.c (check_x_frame): Likewise.
+	* window.c (Fminibuffer_window, Fwindow_at)
+	(Fcurrent_window_configuration): Likewise.
+	(Frun_window_configuration_change_hook, Fwindow_resize_apply):
+	Likewise.  Allow zero number of arguments.  Adjust docstring.
+	* dispnew.c (Fredraw_frame): Likewise.
+	* xfaces.c (frame_or_selected_frame): Remove.
+	(Fx_list_fonts, Finternal_get_lisp_face_attribute, Fface_font)
+	(Finternal_lisp_face_equal_p, Finternal_lisp_face_empty_p)
+	(Fframe_face_alist): Use decode_live_frame.
+	* xfns.c (check_x_frame): Likewise.
+
+2012-11-06  Dmitry Antipov  <dmantipov@yandex.ru>
+
 	* window.c (quad): New function.
 	(Fwindow_edges, Fwindow_pixel_edges, Fwindow_inside_edges)
 	(Fwindow_absolute_pixel_edges, Fwindow_inside_absolute_pixel_edges)
diff --git a/src/buffer.c b/src/buffer.c
index 347f27edc3a..24286610570 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -1543,17 +1543,11 @@ list first, followed by the list of all buffers.  If no other buffer
 exists, return the buffer `*scratch*' (creating it if necessary).  */)
   (register Lisp_Object buffer, Lisp_Object visible_ok, Lisp_Object frame)
 {
-  Lisp_Object tail, buf, pred;
-  Lisp_Object notsogood = Qnil;
+  struct frame *f = decode_any_frame (frame);
+  Lisp_Object tail = f->buffer_list, pred = f->buffer_predicate;
+  Lisp_Object buf, notsogood = Qnil;
 
-  if (NILP (frame))
-    frame = selected_frame;
-
-  CHECK_FRAME (frame);
-
-  pred = frame_buffer_predicate (frame);
   /* Consider buffers that have been seen in the frame first.  */
-  tail = XFRAME (frame)->buffer_list;
   for (; CONSP (tail); tail = XCDR (tail))
     {
       buf = XCAR (tail);
diff --git a/src/dispnew.c b/src/dispnew.c
index 907259a3e94..4758f4ad76f 100644
--- a/src/dispnew.c
+++ b/src/dispnew.c
@@ -3071,14 +3071,12 @@ window_to_frame_hpos (struct window *w, int hpos)
 			    Redrawing Frames
  **********************************************************************/
 
-DEFUN ("redraw-frame", Fredraw_frame, Sredraw_frame, 1, 1, 0,
-       doc: /* Clear frame FRAME and output again what is supposed to appear on it.  */)
+DEFUN ("redraw-frame", Fredraw_frame, Sredraw_frame, 0, 1, 0,
+       doc: /* Clear frame FRAME and output again what is supposed to appear on it.
+If FRAME is omitted or nil, the selected frame is used.  */)
   (Lisp_Object frame)
 {
-  struct frame *f;
-
-  CHECK_LIVE_FRAME (frame);
-  f = XFRAME (frame);
+  struct frame *f = decode_live_frame (frame);
 
   /* Ignore redraw requests, if frame has no glyphs yet.
      (Implementation note: It still has to be checked why we are
diff --git a/src/font.c b/src/font.c
index e960f9b3d13..41dbfd7a757 100644
--- a/src/font.c
+++ b/src/font.c
@@ -3993,16 +3993,11 @@ The optional argument FRAME specifies the frame that the face attributes
 are to be displayed on.  If omitted, the selected frame is used.  */)
   (Lisp_Object font, Lisp_Object frame)
 {
-  struct frame *f;
+  struct frame *f = decode_live_frame (frame);
   Lisp_Object plist[10];
   Lisp_Object val;
   int n = 0;
 
-  if (NILP (frame))
-    frame = selected_frame;
-  CHECK_LIVE_FRAME (frame);
-  f = XFRAME (frame);
-
   if (STRINGP (font))
     {
       int fontset = fs_query_fontset (font, 0);
@@ -4152,18 +4147,15 @@ how close they are to PREFER.  */)
 
 DEFUN ("font-family-list", Ffont_family_list, Sfont_family_list, 0, 1, 0,
        doc: /* List available font families on the current frame.
-Optional argument FRAME, if non-nil, specifies the target frame.  */)
+If FRAME is omitted or nil, the selected frame is used.  */)
   (Lisp_Object frame)
 {
-  FRAME_PTR f;
+  struct frame *f = decode_live_frame (frame);
   struct font_driver_list *driver_list;
-  Lisp_Object list;
+  Lisp_Object list = Qnil;
+
+  XSETFRAME (frame, f);
 
-  if (NILP (frame))
-    frame = selected_frame;
-  CHECK_LIVE_FRAME (frame);
-  f = XFRAME (frame);
-  list = Qnil;
   for (driver_list = f->font_driver_list; driver_list;
        driver_list = driver_list->next)
     if (driver_list->driver->list_family)
@@ -4531,11 +4523,9 @@ DEFUN ("open-font", Fopen_font, Sopen_font, 1, 3, 0,
   (Lisp_Object font_entity, Lisp_Object size, Lisp_Object frame)
 {
   EMACS_INT isize;
+  struct frame *f = decode_live_frame (frame);
 
   CHECK_FONT_ENTITY (font_entity);
-  if (NILP (frame))
-    frame = selected_frame;
-  CHECK_LIVE_FRAME (frame);
 
   if (NILP (size))
     isize = XINT (AREF (font_entity, FONT_SIZE_INDEX));
@@ -4543,7 +4533,7 @@ DEFUN ("open-font", Fopen_font, Sopen_font, 1, 3, 0,
     {
       CHECK_NUMBER_OR_FLOAT (size);
       if (FLOATP (size))
-	isize = POINT_TO_PIXEL (XFLOAT_DATA (size), XFRAME (frame)->resy);
+	isize = POINT_TO_PIXEL (XFLOAT_DATA (size), f->resy);
       else
 	isize = XINT (size);
       if (! (INT_MIN <= isize && isize <= INT_MAX))
@@ -4551,7 +4541,7 @@ DEFUN ("open-font", Fopen_font, Sopen_font, 1, 3, 0,
       if (isize == 0)
 	isize = 120;
     }
-  return font_open_entity (XFRAME (frame), font_entity, isize);
+  return font_open_entity (f, font_entity, isize);
 }
 
 DEFUN ("close-font", Fclose_font, Sclose_font, 1, 2, 0,
@@ -4559,10 +4549,7 @@ DEFUN ("close-font", Fclose_font, Sclose_font, 1, 2, 0,
   (Lisp_Object font_object, Lisp_Object frame)
 {
   CHECK_FONT_OBJECT (font_object);
-  if (NILP (frame))
-    frame = selected_frame;
-  CHECK_LIVE_FRAME (frame);
-  font_close_object (XFRAME (frame), font_object);
+  font_close_object (decode_live_frame (frame), font_object);
   return Qnil;
 }
 
@@ -4847,7 +4834,7 @@ where
 If the named font is not yet loaded, return nil.  */)
   (Lisp_Object name, Lisp_Object frame)
 {
-  FRAME_PTR f;
+  struct frame *f;
   struct font *font;
   Lisp_Object info;
   Lisp_Object font_object;
@@ -4856,10 +4843,7 @@ If the named font is not yet loaded, return nil.  */)
 
   if (! FONTP (name))
     CHECK_STRING (name);
-  if (NILP (frame))
-    frame = selected_frame;
-  CHECK_LIVE_FRAME (frame);
-  f = XFRAME (frame);
+  f = decode_live_frame (frame);
 
   if (STRINGP (name))
     {
diff --git a/src/fontset.c b/src/fontset.c
index da745b31ca1..b76a216bac2 100644
--- a/src/fontset.c
+++ b/src/fontset.c
@@ -1326,17 +1326,14 @@ static Lisp_Object
 check_fontset_name (Lisp_Object name, Lisp_Object *frame)
 {
   int id;
+  struct frame *f = decode_live_frame (*frame);
 
-  if (NILP (*frame))
-    *frame = selected_frame;
-  CHECK_LIVE_FRAME (*frame);
+  XSETFRAME (*frame, f);
 
   if (EQ (name, Qt))
     return Vdefault_fontset;
   if (NILP (name))
-    {
-      id = FRAME_FONTSET (XFRAME (*frame));
-    }
+    id = FRAME_FONTSET (f);
   else
     {
       CHECK_STRING (name);
diff --git a/src/frame.c b/src/frame.c
index 1d375380d56..52be8be270e 100644
--- a/src/frame.c
+++ b/src/frame.c
@@ -131,7 +131,24 @@ fset_minibuffer_window (struct frame *f, Lisp_Object val)
   f->minibuffer_window = val;
 }
 
-
+struct frame *
+decode_live_frame (register Lisp_Object frame)
+{
+  if (NILP (frame))
+    frame = selected_frame;
+  CHECK_LIVE_FRAME (frame);
+  return XFRAME (frame);
+}
+
+struct frame *
+decode_any_frame (register Lisp_Object frame)
+{
+  if (NILP (frame))
+    frame = selected_frame;
+  CHECK_FRAME (frame);
+  return XFRAME (frame);
+}
+
 static void
 set_menu_bar_lines_1 (Lisp_Object window, int n)
 {
@@ -1118,23 +1135,12 @@ other_visible_frames (FRAME_PTR f)
 Lisp_Object
 delete_frame (Lisp_Object frame, Lisp_Object force)
 {
-  struct frame *f;
+  struct frame *f = decode_any_frame (frame);
   struct frame *sf = SELECTED_FRAME ();
   struct kboard *kb;
 
   int minibuffer_selected, is_tooltip_frame;
 
-  if (EQ (frame, Qnil))
-    {
-      f = sf;
-      XSETFRAME (frame, f);
-    }
-  else
-    {
-      CHECK_FRAME (frame);
-      f = XFRAME (frame);
-    }
-
   if (! FRAME_LIVE_P (f))
     return Qnil;
 
@@ -1146,9 +1152,11 @@ delete_frame (Lisp_Object frame, Lisp_Object force)
   if (NILP (XCDR (Vframe_list)) && !EQ (force, Qnoelisp))
     error ("Attempt to delete the only frame");
 
+  XSETFRAME (frame, f);
+
   /* Does this frame have a minibuffer, and is it the surrogate
      minibuffer for any other frame?  */
-  if (FRAME_HAS_MINIBUF_P (XFRAME (frame)))
+  if (FRAME_HAS_MINIBUF_P (f))
     {
       Lisp_Object frames;
 
@@ -1663,25 +1671,23 @@ DEFUN ("make-frame-visible", Fmake_frame_visible, Smake_frame_visible,
 If omitted, FRAME defaults to the currently selected frame.  */)
   (Lisp_Object frame)
 {
-  if (NILP (frame))
-    frame = selected_frame;
-
-  CHECK_LIVE_FRAME (frame);
+  struct frame *f = decode_live_frame (frame);
 
   /* I think this should be done with a hook.  */
 #ifdef HAVE_WINDOW_SYSTEM
-  if (FRAME_WINDOW_P (XFRAME (frame)))
+  if (FRAME_WINDOW_P (f))
     {
-      FRAME_SAMPLE_VISIBILITY (XFRAME (frame));
-      x_make_frame_visible (XFRAME (frame));
+      FRAME_SAMPLE_VISIBILITY (f);
+      x_make_frame_visible (f);
     }
 #endif
 
-  make_frame_visible_1 (XFRAME (frame)->root_window);
+  make_frame_visible_1 (f->root_window);
 
   /* Make menu bar update for the Buffers and Frames menus.  */
   windows_or_buffers_changed++;
 
+  XSETFRAME (frame, f);
   return frame;
 }
 
@@ -1722,16 +1728,13 @@ always considered visible, whether or not they are currently being
 displayed in the terminal.  */)
   (Lisp_Object frame, Lisp_Object force)
 {
-  if (NILP (frame))
-    frame = selected_frame;
+  struct frame *f = decode_live_frame (frame);
 
-  CHECK_LIVE_FRAME (frame);
-
-  if (NILP (force) && !other_visible_frames (XFRAME (frame)))
+  if (NILP (force) && !other_visible_frames (f))
     error ("Attempt to make invisible the sole visible or iconified frame");
 
   /* Don't allow minibuf_window to remain on a deleted frame.  */
-  if (EQ (XFRAME (frame)->minibuffer_window, minibuf_window))
+  if (EQ (f->minibuffer_window, minibuf_window))
     {
       struct frame *sf = XFRAME (selected_frame);
       /* Use set_window_buffer instead of Fset_window_buffer (see
@@ -1743,8 +1746,8 @@ displayed in the terminal.  */)
 
   /* I think this should be done with a hook.  */
 #ifdef HAVE_WINDOW_SYSTEM
-  if (FRAME_WINDOW_P (XFRAME (frame)))
-    x_make_frame_invisible (XFRAME (frame));
+  if (FRAME_WINDOW_P (f))
+    x_make_frame_invisible (f);
 #endif
 
   /* Make menu bar update for the Buffers and Frames menus.  */
@@ -1759,19 +1762,10 @@ DEFUN ("iconify-frame", Ficonify_frame, Siconify_frame,
 If omitted, FRAME defaults to the currently selected frame.  */)
   (Lisp_Object frame)
 {
-  if (NILP (frame))
-    frame = selected_frame;
-
-  CHECK_LIVE_FRAME (frame);
-
-#if 0 /* This isn't logically necessary, and it can do GC.  */
-  /* Don't let the frame remain selected.  */
-  if (EQ (frame, selected_frame))
-    Fhandle_switch_frame (next_frame (frame, Qt));
-#endif
+  struct frame *f = decode_live_frame (frame);
 
   /* Don't allow minibuf_window to remain on an iconified frame.  */
-  if (EQ (XFRAME (frame)->minibuffer_window, minibuf_window))
+  if (EQ (f->minibuffer_window, minibuf_window))
     {
       struct frame *sf = XFRAME (selected_frame);
       /* Use set_window_buffer instead of Fset_window_buffer (see
@@ -1783,8 +1777,8 @@ If omitted, FRAME defaults to the currently selected frame.  */)
 
   /* I think this should be done with a hook.  */
 #ifdef HAVE_WINDOW_SYSTEM
-  if (FRAME_WINDOW_P (XFRAME (frame)))
-      x_iconify_frame (XFRAME (frame));
+  if (FRAME_WINDOW_P (f))
+      x_iconify_frame (f);
 #endif
 
   /* Make menu bar update for the Buffers and Frames menus.  */
@@ -1848,13 +1842,9 @@ If Emacs is displaying on an ordinary terminal or some other device which
 doesn't support multiple overlapping frames, this function selects FRAME.  */)
   (Lisp_Object frame)
 {
-  struct frame *f;
-  if (NILP (frame))
-    frame = selected_frame;
+  struct frame *f = decode_live_frame (frame);
 
-  CHECK_LIVE_FRAME (frame);
-
-  f = XFRAME (frame);
+  XSETFRAME (frame, f);
 
   if (FRAME_TERMCAP_P (f))
     /* On a text terminal select FRAME.  */
@@ -1877,14 +1867,7 @@ If Emacs is displaying on an ordinary terminal or some other device which
 doesn't support multiple overlapping frames, this function does nothing.  */)
   (Lisp_Object frame)
 {
-  struct frame *f;
-
-  if (NILP (frame))
-    frame = selected_frame;
-
-  CHECK_LIVE_FRAME (frame);
-
-  f = XFRAME (frame);
+  struct frame *f = decode_live_frame (frame);
 
   if (FRAME_TERMINAL (f)->frame_raise_lower_hook)
     (*FRAME_TERMINAL (f)->frame_raise_lower_hook) (f, 0);
@@ -1920,18 +1903,14 @@ is affected by `select-frame', while the latter is not.
 The redirection lasts until `redirect-frame-focus' is called to change it.  */)
   (Lisp_Object frame, Lisp_Object focus_frame)
 {
-  struct frame *f;
-
   /* Note that we don't check for a live frame here.  It's reasonable
      to redirect the focus of a frame you're about to delete, if you
      know what other frame should receive those keystrokes.  */
-  CHECK_FRAME (frame);
+  struct frame *f = decode_any_frame (frame);
 
   if (! NILP (focus_frame))
     CHECK_LIVE_FRAME (focus_frame);
 
-  f = XFRAME (frame);
-
   fset_focus_frame (f, focus_frame);
 
   if (FRAME_TERMINAL (f)->frame_rehighlight_hook)
@@ -1941,15 +1920,14 @@ The redirection lasts until `redirect-frame-focus' is called to change it.  */)
 }
 
 
-DEFUN ("frame-focus", Fframe_focus, Sframe_focus, 1, 1, 0,
+DEFUN ("frame-focus", Fframe_focus, Sframe_focus, 0, 1, 0,
        doc: /* Return the frame to which FRAME's keystrokes are currently being sent.
-This returns nil if FRAME's focus is not redirected.
+If FRAME is omitted or nil, the selected frame is used.
+Return nil if FRAME's focus is not redirected.
 See `redirect-frame-focus'.  */)
   (Lisp_Object frame)
 {
-  CHECK_LIVE_FRAME (frame);
-
-  return FRAME_FOCUS_FRAME (XFRAME (frame));
+  return FRAME_FOCUS_FRAME (decode_live_frame (frame));
 }
 
 
@@ -1972,22 +1950,6 @@ get_frame_param (register struct frame *frame, Lisp_Object prop)
 }
 #endif
 
-/* Return the buffer-predicate of the selected frame.  */
-
-Lisp_Object
-frame_buffer_predicate (Lisp_Object frame)
-{
-  return XFRAME (frame)->buffer_predicate;
-}
-
-/* Return the buffer-list of the selected frame.  */
-
-static Lisp_Object
-frame_buffer_list (Lisp_Object frame)
-{
-  return XFRAME (frame)->buffer_list;
-}
-
 /* Discard BUFFER from the buffer-list and buried-buffer-list of each frame.  */
 
 void
@@ -2166,20 +2128,14 @@ DEFUN ("frame-parameters", Fframe_parameters, Sframe_parameters, 0, 1, 0,
        doc: /* Return the parameters-alist of frame FRAME.
 It is a list of elements of the form (PARM . VALUE), where PARM is a symbol.
 The meaningful PARMs depend on the kind of frame.
-If FRAME is omitted, return information on the currently selected frame.  */)
+If FRAME is omitted or nil, return information on the currently selected frame.  */)
   (Lisp_Object frame)
 {
   Lisp_Object alist;
-  FRAME_PTR f;
+  struct frame *f = decode_any_frame (frame);
   int height, width;
   struct gcpro gcpro1;
 
-  if (NILP (frame))
-    frame = selected_frame;
-
-  CHECK_FRAME (frame);
-  f = XFRAME (frame);
-
   if (!FRAME_LIVE_P (f))
     return Qnil;
 
@@ -2240,9 +2196,8 @@ If FRAME is omitted, return information on the currently selected frame.  */)
 		   : FRAME_MINIBUF_ONLY_P (f) ? Qonly
 		   : FRAME_MINIBUF_WINDOW (f)));
   store_in_alist (&alist, Qunsplittable, (FRAME_NO_SPLIT_P (f) ? Qt : Qnil));
-  store_in_alist (&alist, Qbuffer_list, frame_buffer_list (frame));
-  store_in_alist (&alist, Qburied_buffer_list,
-		  XFRAME (frame)->buried_buffer_list);
+  store_in_alist (&alist, Qbuffer_list, f->buffer_list);
+  store_in_alist (&alist, Qburied_buffer_list, f->buried_buffer_list);
 
   /* I think this should be done with a hook.  */
 #ifdef HAVE_WINDOW_SYSTEM
@@ -2267,17 +2222,12 @@ DEFUN ("frame-parameter", Fframe_parameter, Sframe_parameter, 2, 2, 0,
 If FRAME is nil, describe the currently selected frame.  */)
   (Lisp_Object frame, Lisp_Object parameter)
 {
-  struct frame *f;
-  Lisp_Object value;
+  struct frame *f = decode_any_frame (frame);
+  Lisp_Object value = Qnil;
 
-  if (NILP (frame))
-    frame = selected_frame;
-  else
-    CHECK_FRAME (frame);
   CHECK_SYMBOL (parameter);
 
-  f = XFRAME (frame);
-  value = Qnil;
+  XSETFRAME (frame, f);
 
   if (FRAME_LIVE_P (f))
     {
@@ -2357,14 +2307,9 @@ Note that this functionality is obsolete as of Emacs 22.2, and its
 use is not recommended.  Explicitly check for a frame-parameter instead.  */)
   (Lisp_Object frame, Lisp_Object alist)
 {
-  FRAME_PTR f;
+  struct frame *f = decode_live_frame (frame);
   register Lisp_Object tail, prop, val;
 
-  if (EQ (frame, Qnil))
-    frame = selected_frame;
-  CHECK_LIVE_FRAME (frame);
-  f = XFRAME (frame);
-
   /* I think this should be done with a hook.  */
 #ifdef HAVE_WINDOW_SYSTEM
   if (FRAME_WINDOW_P (f))
@@ -2419,18 +2364,13 @@ use is not recommended.  Explicitly check for a frame-parameter instead.  */)
 DEFUN ("frame-char-height", Fframe_char_height, Sframe_char_height,
        0, 1, 0,
        doc: /* Height in pixels of a line in the font in frame FRAME.
-If FRAME is omitted, the selected frame is used.
+If FRAME is omitted or nil, the selected frame is used.
 For a terminal frame, the value is always 1.  */)
   (Lisp_Object frame)
 {
-  struct frame *f;
-
-  if (NILP (frame))
-    frame = selected_frame;
-  CHECK_FRAME (frame);
-  f = XFRAME (frame);
-
 #ifdef HAVE_WINDOW_SYSTEM
+  struct frame *f = decode_any_frame (frame);
+
   if (FRAME_WINDOW_P (f))
     return make_number (x_char_height (f));
   else
@@ -2442,19 +2382,14 @@ For a terminal frame, the value is always 1.  */)
 DEFUN ("frame-char-width", Fframe_char_width, Sframe_char_width,
        0, 1, 0,
        doc: /* Width in pixels of characters in the font in frame FRAME.
-If FRAME is omitted, the selected frame is used.
+If FRAME is omitted or nil, the selected frame is used.
 On a graphical screen, the width is the standard width of the default font.
 For a terminal screen, the value is always 1.  */)
   (Lisp_Object frame)
 {
-  struct frame *f;
-
-  if (NILP (frame))
-    frame = selected_frame;
-  CHECK_FRAME (frame);
-  f = XFRAME (frame);
-
 #ifdef HAVE_WINDOW_SYSTEM
+  struct frame *f = decode_any_frame (frame);
+
   if (FRAME_WINDOW_P (f))
     return make_number (x_char_width (f));
   else
@@ -2465,7 +2400,7 @@ For a terminal screen, the value is always 1.  */)
 DEFUN ("frame-pixel-height", Fframe_pixel_height,
        Sframe_pixel_height, 0, 1, 0,
        doc: /* Return a FRAME's height in pixels.
-If FRAME is omitted, the selected frame is used.  The exact value
+If FRAME is omitted or nil, the selected frame is used.  The exact value
 of the result depends on the window-system and toolkit in use:
 
 In the Gtk+ version of Emacs, it includes only any window (including
@@ -2480,12 +2415,7 @@ result is really in characters rather than pixels (i.e., is identical
 to `frame-height'). */)
   (Lisp_Object frame)
 {
-  struct frame *f;
-
-  if (NILP (frame))
-    frame = selected_frame;
-  CHECK_FRAME (frame);
-  f = XFRAME (frame);
+  struct frame *f = decode_any_frame (frame);
 
 #ifdef HAVE_WINDOW_SYSTEM
   if (FRAME_WINDOW_P (f))
@@ -2499,15 +2429,10 @@ DEFUN ("frame-pixel-width", Fframe_pixel_width,
        Sframe_pixel_width, 0, 1, 0,
        doc: /* Return FRAME's width in pixels.
 For a terminal frame, the result really gives the width in characters.
-If FRAME is omitted, the selected frame is used.  */)
+If FRAME is omitted or nil, the selected frame is used.  */)
   (Lisp_Object frame)
 {
-  struct frame *f;
-
-  if (NILP (frame))
-    frame = selected_frame;
-  CHECK_FRAME (frame);
-  f = XFRAME (frame);
+  struct frame *f = decode_any_frame (frame);
 
 #ifdef HAVE_WINDOW_SYSTEM
   if (FRAME_WINDOW_P (f))
@@ -2521,17 +2446,15 @@ DEFUN ("tool-bar-pixel-width", Ftool_bar_pixel_width,
        Stool_bar_pixel_width, 0, 1, 0,
        doc: /* Return width in pixels of FRAME's tool bar.
 The result is greater than zero only when the tool bar is on the left
-or right side of FRAME.  If FRAME is omitted, the selected frame is
-used.  */)
+or right side of FRAME.  If FRAME is omitted or nil, the selected frame
+is used.  */)
   (Lisp_Object frame)
 {
-  if (NILP (frame))
-    frame = selected_frame;
-  CHECK_FRAME (frame);
-
 #ifdef FRAME_TOOLBAR_WIDTH
-  if (FRAME_WINDOW_P (XFRAME (frame)))
-    return make_number (FRAME_TOOLBAR_WIDTH (XFRAME (frame)));
+  struct frame *f = decode_any_frame (frame);
+
+  if (FRAME_WINDOW_P (f))
+    return make_number (FRAME_TOOLBAR_WIDTH (f));
 #endif
   return make_number (0);
 }
@@ -2542,13 +2465,9 @@ Optional third arg non-nil means that redisplay should use LINES lines
 but that the idea of the actual height of the frame should not be changed.  */)
   (Lisp_Object frame, Lisp_Object lines, Lisp_Object pretend)
 {
-  register struct frame *f;
+  register struct frame *f = decode_live_frame (frame);
 
   CHECK_TYPE_RANGED_INTEGER (int, lines);
-  if (NILP (frame))
-    frame = selected_frame;
-  CHECK_LIVE_FRAME (frame);
-  f = XFRAME (frame);
 
   /* I think this should be done with a hook.  */
 #ifdef HAVE_WINDOW_SYSTEM
@@ -2570,12 +2489,9 @@ Optional third arg non-nil means that redisplay should use COLS columns
 but that the idea of the actual width of the frame should not be changed.  */)
   (Lisp_Object frame, Lisp_Object cols, Lisp_Object pretend)
 {
-  register struct frame *f;
+  register struct frame *f = decode_live_frame (frame);
+
   CHECK_TYPE_RANGED_INTEGER (int, cols);
-  if (NILP (frame))
-    frame = selected_frame;
-  CHECK_LIVE_FRAME (frame);
-  f = XFRAME (frame);
 
   /* I think this should be done with a hook.  */
 #ifdef HAVE_WINDOW_SYSTEM
@@ -4292,12 +4208,7 @@ Otherwise it returns nil.  FRAME omitted or nil means the
 selected frame.  This is useful when `make-pointer-invisible' is set.  */)
   (Lisp_Object frame)
 {
-  if (NILP (frame))
-    frame = selected_frame;
-
-  CHECK_FRAME (frame);
-
-  return (XFRAME (frame)->pointer_invisible ? Qnil : Qt);
+  return decode_any_frame (frame)->pointer_invisible ? Qnil : Qt;
 }
 
 
diff --git a/src/frame.h b/src/frame.h
index eea618df797..1dc3ebbaf13 100644
--- a/src/frame.h
+++ b/src/frame.h
@@ -943,6 +943,8 @@ extern Lisp_Object Qnoelisp;
 extern struct frame *last_nonminibuf_frame;
 
 extern void set_menu_bar_lines (struct frame *, Lisp_Object, Lisp_Object);
+extern struct frame *decode_live_frame (Lisp_Object);
+extern struct frame *decode_any_frame (Lisp_Object);
 extern struct frame *make_initial_frame (void);
 extern struct frame *make_frame (int);
 #ifdef HAVE_WINDOW_SYSTEM
diff --git a/src/lisp.h b/src/lisp.h
index e9f47f4ed27..1a76a502ca0 100644
--- a/src/lisp.h
+++ b/src/lisp.h
@@ -3298,7 +3298,6 @@ extern Lisp_Object do_switch_frame (Lisp_Object, int, int, Lisp_Object);
 #if HAVE_NS
 extern Lisp_Object get_frame_param (struct frame *, Lisp_Object);
 #endif
-extern Lisp_Object frame_buffer_predicate (Lisp_Object);
 extern void frames_discard_buffer (Lisp_Object);
 extern void syms_of_frame (void);
 
diff --git a/src/terminal.c b/src/terminal.c
index 2c0c60e7345..854ca61f19c 100644
--- a/src/terminal.c
+++ b/src/terminal.c
@@ -360,14 +360,7 @@ If FRAME is nil, the selected frame is used.
 The terminal device is represented by its integer identifier.  */)
   (Lisp_Object frame)
 {
-  struct terminal *t;
-
-  if (NILP (frame))
-    frame = selected_frame;
-
-  CHECK_LIVE_FRAME (frame);
-
-  t = FRAME_TERMINAL (XFRAME (frame));
+  struct terminal *t = FRAME_TERMINAL (decode_live_frame (frame));
 
   if (!t)
     return Qnil;
diff --git a/src/w32fns.c b/src/w32fns.c
index 18e29ecaaf5..24760054523 100644
--- a/src/w32fns.c
+++ b/src/w32fns.c
@@ -264,12 +264,8 @@ have_menus_p (void)
 FRAME_PTR
 check_x_frame (Lisp_Object frame)
 {
-  FRAME_PTR f;
+  struct frame *f = decode_live_frame (frame);
 
-  if (NILP (frame))
-    frame = selected_frame;
-  CHECK_LIVE_FRAME (frame);
-  f = XFRAME (frame);
   if (! FRAME_W32_P (f))
     error ("Non-W32 frame used");
   return f;
diff --git a/src/window.c b/src/window.c
index 75a8d42d8d1..c32234b5fcd 100644
--- a/src/window.c
+++ b/src/window.c
@@ -340,10 +340,7 @@ DEFUN ("minibuffer-window", Fminibuffer_window, Sminibuffer_window, 0, 1, 0,
 If FRAME is omitted or nil, it defaults to the selected frame.  */)
   (Lisp_Object frame)
 {
-  if (NILP (frame))
-    frame = selected_frame;
-  CHECK_LIVE_FRAME (frame);
-  return FRAME_MINIBUF_WINDOW (XFRAME (frame));
+  return FRAME_MINIBUF_WINDOW (decode_live_frame (frame));
 }
 
 DEFUN ("window-minibuffer-p", Fwindow_minibuffer_p,
@@ -1371,12 +1368,7 @@ The top left corner of the frame is considered to be row 0,
 column 0.  */)
   (Lisp_Object x, Lisp_Object y, Lisp_Object frame)
 {
-  struct frame *f;
-
-  if (NILP (frame))
-    frame = selected_frame;
-  CHECK_LIVE_FRAME (frame);
-  f = XFRAME (frame);
+  struct frame *f = decode_live_frame (frame);
 
   /* Check that arguments are integers or floats.  */
   CHECK_NUMBER_OR_FLOAT (x);
@@ -3109,12 +3101,12 @@ run_window_configuration_change_hook (struct frame *f)
 }
 
 DEFUN ("run-window-configuration-change-hook", Frun_window_configuration_change_hook,
-       Srun_window_configuration_change_hook, 1, 1, 0,
-       doc: /* Run `window-configuration-change-hook' for FRAME.  */)
+       Srun_window_configuration_change_hook, 0, 1, 0,
+       doc: /* Run `window-configuration-change-hook' for FRAME. 
+If FRAME is omitted or nil, it defaults to the selected frame.  */)
   (Lisp_Object frame)
 {
-  CHECK_LIVE_FRAME (frame);
-  run_window_configuration_change_hook (XFRAME (frame));
+  run_window_configuration_change_hook (decode_live_frame (frame));
   return Qnil;
 }
 
@@ -3641,10 +3633,12 @@ window_resize_apply (struct window *w, int horflag)
 }
 
 
-DEFUN ("window-resize-apply", Fwindow_resize_apply, Swindow_resize_apply, 1, 2, 0,
+DEFUN ("window-resize-apply", Fwindow_resize_apply, Swindow_resize_apply, 0, 2, 0,
        doc: /* Apply requested size values for window-tree of FRAME.
-Optional argument HORIZONTAL omitted or nil means apply requested height
-values.  HORIZONTAL non-nil means apply requested width values.
+If FRAME is omitted or nil, it defaults to the selected frame.
+
+Optional argument HORIZONTAL omitted or nil means apply requested
+height values.  HORIZONTAL non-nil means apply requested width values.
 
 This function checks whether the requested values sum up to a valid
 window layout, recursively assigns the new sizes of all child windows
@@ -3655,17 +3649,10 @@ Note: This function does not check any of `window-fixed-size-p',
 be applied on the Elisp level.  */)
      (Lisp_Object frame, Lisp_Object horizontal)
 {
-  struct frame *f;
-  struct window *r;
+  struct frame *f = decode_live_frame (frame);
+  struct window *r = XWINDOW (FRAME_ROOT_WINDOW (f));
   int horflag = !NILP (horizontal);
 
-  if (NILP (frame))
-    frame = selected_frame;
-  CHECK_LIVE_FRAME (frame);
-
-  f = XFRAME (frame);
-  r = XWINDOW (FRAME_ROOT_WINDOW (f));
-
   if (!window_resize_check (r, horflag)
       || ! EQ (r->new_total,
 	       (horflag ? r->total_cols : r->total_lines)))
@@ -6148,12 +6135,7 @@ saved by this function.  */)
   register int n_windows;
   register struct save_window_data *data;
   register int i;
-  FRAME_PTR f;
-
-  if (NILP (frame))
-    frame = selected_frame;
-  CHECK_LIVE_FRAME (frame);
-  f = XFRAME (frame);
+  struct frame *f = decode_live_frame (frame);
 
   n_windows = count_windows (XWINDOW (FRAME_ROOT_WINDOW (f)));
   data = ALLOCATE_PSEUDOVECTOR (struct save_window_data, frame_cols,
diff --git a/src/xdisp.c b/src/xdisp.c
index 1ff7819f34d..c01f5deab83 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -11916,19 +11916,14 @@ tool_bar_lines_needed (struct frame *f, int *n_rows)
 
 DEFUN ("tool-bar-lines-needed", Ftool_bar_lines_needed, Stool_bar_lines_needed,
        0, 1, 0,
-       doc: /* Return the number of lines occupied by the tool bar of FRAME.  */)
+       doc: /* Return the number of lines occupied by the tool bar of FRAME.
+If FRAME is nil or omitted, use the selected frame.  */)
   (Lisp_Object frame)
 {
-  struct frame *f;
+  struct frame *f = decode_any_frame (frame);
   struct window *w;
   int nlines = 0;
 
-  if (NILP (frame))
-    frame = selected_frame;
-  else
-    CHECK_FRAME (frame);
-  f = XFRAME (frame);
-
   if (WINDOWP (f->tool_bar_window)
       && (w = XWINDOW (f->tool_bar_window),
 	  WINDOW_TOTAL_LINES (w) > 0))
diff --git a/src/xfaces.c b/src/xfaces.c
index 221387c4b6d..41c618612ac 100644
--- a/src/xfaces.c
+++ b/src/xfaces.c
@@ -669,23 +669,6 @@ x_free_gc (struct frame *f, GC gc)
 }
 #endif  /* HAVE_NS */
 
-/* If FRAME is nil, return a pointer to the selected frame.
-   Otherwise, check that FRAME is a live frame, and return a pointer
-   to it.  NPARAM is the parameter number of FRAME, for
-   CHECK_LIVE_FRAME.  This is here because it's a frequent pattern in
-   Lisp function definitions.  */
-
-static struct frame *
-frame_or_selected_frame (Lisp_Object frame, int nparam)
-{
-  if (NILP (frame))
-    frame = selected_frame;
-
-  CHECK_LIVE_FRAME (frame);
-  return XFRAME (frame);
-}
-
-
 /***********************************************************************
 			   Frames and faces
  ***********************************************************************/
@@ -1204,15 +1187,9 @@ FRAME specifies the frame and thus the display for interpreting COLOR.
 If FRAME is nil or omitted, use the selected frame.  */)
   (Lisp_Object color, Lisp_Object frame)
 {
-  struct frame *f;
-
   CHECK_STRING (color);
-  if (NILP (frame))
-    frame = selected_frame;
-  else
-    CHECK_FRAME (frame);
-  f = XFRAME (frame);
-  return face_color_gray_p (f, SSDATA (color)) ? Qt : Qnil;
+  return (face_color_gray_p (decode_any_frame (frame), SSDATA (color))
+	  ? Qt : Qnil);
 }
 
 
@@ -1225,17 +1202,10 @@ If FRAME is nil or omitted, use the selected frame.
 COLOR must be a valid color name.  */)
   (Lisp_Object color, Lisp_Object frame, Lisp_Object background_p)
 {
-  struct frame *f;
-
   CHECK_STRING (color);
-  if (NILP (frame))
-    frame = selected_frame;
-  else
-    CHECK_FRAME (frame);
-  f = XFRAME (frame);
-  if (face_color_supported_p (f, SSDATA (color), !NILP (background_p)))
-    return Qt;
-  return Qnil;
+  return (face_color_supported_p (decode_any_frame (frame),
+				  SSDATA (color), !NILP (background_p))
+	  ? Qt : Qnil);
 }
 
 
@@ -1683,9 +1653,7 @@ the WIDTH times as wide as FACE on FRAME.  */)
 
   /* We can't simply call check_x_frame because this function may be
      called before any frame is created.  */
-  if (NILP (frame))
-    frame = selected_frame;
-  f = frame_or_selected_frame (frame, 2);
+  f = decode_live_frame (frame);
   if (! FRAME_WINDOW_P (f))
     {
       /* Perhaps we have not yet created any frame.  */
@@ -1693,6 +1661,8 @@ the WIDTH times as wide as FACE on FRAME.  */)
       frame = Qnil;
       face = Qnil;
     }
+  else
+    XSETFRAME (frame, f);
 
   /* Determine the width standard for comparison with the fonts we find.  */
 
@@ -3679,21 +3649,12 @@ frame.  If FRAME is t, report on the defaults for face SYMBOL (for new
 frames).  If FRAME is omitted or nil, use the selected frame.  */)
   (Lisp_Object symbol, Lisp_Object keyword, Lisp_Object frame)
 {
-  Lisp_Object lface, value = Qnil;
+  struct frame *f = EQ (frame, Qt) ? NULL : decode_live_frame (frame);
+  Lisp_Object lface = lface_from_face_name (f, symbol, 1), value = Qnil;
 
   CHECK_SYMBOL (symbol);
   CHECK_SYMBOL (keyword);
 
-  if (EQ (frame, Qt))
-    lface = lface_from_face_name (NULL, symbol, 1);
-  else
-    {
-      if (NILP (frame))
-	frame = selected_frame;
-      CHECK_LIVE_FRAME (frame);
-      lface = lface_from_face_name (XFRAME (frame), symbol, 1);
-    }
-
   if (EQ (keyword, QCfamily))
     value = LFACE_FAMILY (lface);
   else if (EQ (keyword, QCfoundry))
@@ -3876,7 +3837,7 @@ return the font name used for CHARACTER.  */)
     }
   else
     {
-      struct frame *f = frame_or_selected_frame (frame, 1);
+      struct frame *f = decode_live_frame (frame);
       int face_id = lookup_named_face (f, face, 1);
       struct face *fface = FACE_FROM_ID (f, face_id);
 
@@ -3963,14 +3924,11 @@ If FRAME is omitted or nil, use the selected frame.  */)
   struct frame *f;
   Lisp_Object lface1, lface2;
 
-  if (EQ (frame, Qt))
-    f = NULL;
-  else
-    /* Don't use check_x_frame here because this function is called
-       before X frames exist.  At that time, if FRAME is nil,
-       selected_frame will be used which is the frame dumped with
-       Emacs.  That frame is not an X frame.  */
-    f = frame_or_selected_frame (frame, 2);
+  /* Don't use check_x_frame here because this function is called
+     before X frames exist.  At that time, if FRAME is nil,
+     selected_frame will be used which is the frame dumped with
+     Emacs.  That frame is not an X frame.  */
+  f = EQ (frame, Qt) ? NULL : decode_live_frame (frame);
 
   lface1 = lface_from_face_name (f, face1, 1);
   lface2 = lface_from_face_name (f, face2, 1);
@@ -3988,20 +3946,10 @@ If FRAME is t, report on the defaults for face FACE (for new frames).
 If FRAME is omitted or nil, use the selected frame.  */)
   (Lisp_Object face, Lisp_Object frame)
 {
-  struct frame *f;
-  Lisp_Object lface;
+  struct frame *f = EQ (frame, Qt) ? NULL : decode_live_frame (frame);
+  Lisp_Object lface = lface_from_face_name (f, face, 1);
   int i;
 
-  if (NILP (frame))
-    frame = selected_frame;
-  CHECK_LIVE_FRAME (frame);
-  f = XFRAME (frame);
-
-  if (EQ (frame, Qt))
-    lface = lface_from_face_name (NULL, face, 1);
-  else
-    lface = lface_from_face_name (f, face, 1);
-
   for (i = 1; i < LFACE_VECTOR_SIZE; ++i)
     if (!UNSPECIFIEDP (AREF (lface, i)))
       break;
@@ -4016,8 +3964,7 @@ DEFUN ("frame-face-alist", Fframe_face_alist, Sframe_face_alist,
 For internal use only.  */)
   (Lisp_Object frame)
 {
-  struct frame *f = frame_or_selected_frame (frame, 0);
-  return f->face_alist;
+  return decode_live_frame (frame)->face_alist;
 }
 
 
@@ -4205,14 +4152,9 @@ or lists of the form (RED GREEN BLUE).
 If FRAME is unspecified or nil, the current frame is used.  */)
   (Lisp_Object color1, Lisp_Object color2, Lisp_Object frame)
 {
-  struct frame *f;
+  struct frame *f = decode_live_frame (frame);
   XColor cdef1, cdef2;
 
-  if (NILP (frame))
-    frame = selected_frame;
-  CHECK_LIVE_FRAME (frame);
-  f = XFRAME (frame);
-
   if (!(CONSP (color1) && parse_rgb_list (color1, &cdef1))
       && !(STRINGP (color1) && defined_color (f, SSDATA (color1), &cdef1, 0)))
     signal_error ("Invalid color", color1);
diff --git a/src/xfns.c b/src/xfns.c
index aca227385bf..9c99902b93d 100644
--- a/src/xfns.c
+++ b/src/xfns.c
@@ -164,12 +164,8 @@ have_menus_p (void)
 FRAME_PTR
 check_x_frame (Lisp_Object frame)
 {
-  FRAME_PTR f;
+  struct frame *f = decode_live_frame (frame);
 
-  if (NILP (frame))
-    frame = selected_frame;
-  CHECK_LIVE_FRAME (frame);
-  f = XFRAME (frame);
   if (! FRAME_X_P (f))
     error ("Non-X frame used");
   return f;