* dispextern.h (SET_TEXT_POS_FROM_MARKER): Indent.

(CLIP_TEXT_POS_FROM_MARKER): New macro.
* dispnew.c (buffer_posn_from_coords):
* window.c (Fwindow_end, displayed_window_lines):
* xdisp.c (redisplay_mode_lines): Use it.

src/ChangeLog

+2013-09-01  Dmitry Antipov  <dmantipov@yandex.ru>
+
+	* dispextern.h (SET_TEXT_POS_FROM_MARKER): Indent.
+	(CLIP_TEXT_POS_FROM_MARKER): New macro.
+	* dispnew.c (buffer_posn_from_coords):
+	* window.c (Fwindow_end, displayed_window_lines):
+	* xdisp.c (redisplay_mode_lines): Use it.
+
 2013-09-01  Jan Djärv  <jan.h.d@swipnet.se>
 
 	* fontset.c (face_for_char): Check char in the current face font first

src/dispextern.h

@@ -223,8 +223,16 @@ struct text_pos
 /* Set text position POS from marker MARKER.  */
 
 #define SET_TEXT_POS_FROM_MARKER(POS, MARKER)		\
-     (CHARPOS (POS) = marker_position ((MARKER)),	\
-      BYTEPOS (POS) = marker_byte_position ((MARKER)))
+  (CHARPOS (POS) = marker_position (MARKER),		\
+   BYTEPOS (POS) = marker_byte_position (MARKER))
+
+/* Like above, but clip POS within accessible range.  */
+
+#define CLIP_TEXT_POS_FROM_MARKER(POS, MARKER)		\
+  (CHARPOS (POS) = clip_to_bounds			\
+   (BEGV, marker_position (MARKER), ZV),		\
+   BYTEPOS (POS) = clip_to_bounds			\
+   (BEGV_BYTE, marker_byte_position (MARKER), ZV_BYTE))
 
 /* Set marker MARKER from text position POS.  */
 

src/dispnew.c

@@ -5066,9 +5066,7 @@ buffer_posn_from_coords (struct window *w, int *x, int *y, struct display_pos *p
      wrong thing with `face-remapping-alist' (bug#2044).  */
   Fset_buffer (w->contents);
   itdata = bidi_shelve_cache ();
-  SET_TEXT_POS_FROM_MARKER (startp, w->start);
-  CHARPOS (startp) = min (ZV, max (BEGV, CHARPOS (startp)));
-  BYTEPOS (startp) = min (ZV_BYTE, max (BEGV_BYTE, BYTEPOS (startp)));
+  CLIP_TEXT_POS_FROM_MARKER (startp, w->start);
   start_display (&it, w, startp);
   /* start_display takes into account the header-line row, but IT's
      vpos still counts from the glyph row that includes the window's

src/window.c

@@ -1494,7 +1494,6 @@ if it isn't already recorded.  */)
       && !noninteractive)
     {
       struct text_pos startp;
-      ptrdiff_t charpos = marker_position (w->start);
       struct it it;
       struct buffer *old_buffer = NULL;
       void *itdata = NULL;
@@ -1512,12 +1511,7 @@ if it isn't already recorded.  */)
          `-l' containing a call to `rmail' with subsequent other
          commands.  At the end, W->start happened to be BEG, while
          rmail had already narrowed the buffer.  */
-      if (charpos < BEGV)
-	SET_TEXT_POS (startp, BEGV, BEGV_BYTE);
-      else if (charpos > ZV)
-	SET_TEXT_POS (startp, ZV, ZV_BYTE);
-      else
-	SET_TEXT_POS_FROM_MARKER (startp, w->start);
+      CLIP_TEXT_POS_FROM_MARKER (startp, w->start);
 
       itdata = bidi_shelve_cache ();
       start_display (&it, w, startp);
@@ -5038,7 +5032,6 @@ displayed_window_lines (struct window *w)
 {
   struct it it;
   struct text_pos start;
-  ptrdiff_t charpos = marker_position (w->start);
   int height = window_box_height (w);
   struct buffer *old_buffer;
   int bottom_y;
@@ -5055,12 +5048,7 @@ displayed_window_lines (struct window *w)
   /* In case W->start is out of the accessible range, do something
      reasonable.  This happens in Info mode when Info-scroll-down
      calls (recenter -1) while W->start is 1.  */
-  if (charpos < BEGV)
-    SET_TEXT_POS (start, BEGV, BEGV_BYTE);
-  else if (charpos > ZV)
-    SET_TEXT_POS (start, ZV, ZV_BYTE);
-  else
-    SET_TEXT_POS_FROM_MARKER (start, w->start);
+  CLIP_TEXT_POS_FROM_MARKER (start, w->start);
 
   itdata = bidi_shelve_cache ();
   start_display (&it, w, start);

src/xdisp.c

@@ -20606,13 +20606,8 @@ redisplay_mode_lines (Lisp_Object window, int force)
 	    {
 	      struct text_pos pt;
-	      SET_TEXT_POS_FROM_MARKER (pt, w->pointm);
-	      if (CHARPOS (pt) < BEGV)
-		TEMP_SET_PT_BOTH (BEGV, BEGV_BYTE);
-	      else if (CHARPOS (pt) > (ZV - 1))
-		TEMP_SET_PT_BOTH (ZV, ZV_BYTE);
-	      else
-		TEMP_SET_PT_BOTH (CHARPOS (pt), BYTEPOS (pt));
+	      CLIP_TEXT_POS_FROM_MARKER (pt, w->pointm);
+	      TEMP_SET_PT_BOTH (CHARPOS (pt), BYTEPOS (pt));
 	    }
 	  /* Display mode lines.  */