Avoid character to byte conversions in motion subroutines.

[bpt/emacs.git] / src / window.c

diff --git a/src/window.c b/src/window.c
index c2da2e8..7769613 100644 (file)
--- a/src/window.c
+++ b/src/window.c
@@ -300,15 +300,6 @@ wset_buffer (struct window *w, Lisp_Object val)
   adjust_window_count (w, 1);
 }
 
-/* Build a frequently used 4-integer (X Y W H) list.  */
-
-static Lisp_Object
-list4i (EMACS_INT x, EMACS_INT y, EMACS_INT w, EMACS_INT h)
-{
-  return list4 (make_number (x), make_number (y),
-               make_number (w), make_number (h));
-}
-
 DEFUN ("windowp", Fwindowp, Swindowp, 1, 1, 0,
        doc: /* Return t if OBJECT is a window and nil otherwise.  */)
   (Lisp_Object object)
@@ -2752,7 +2743,7 @@ window-start value is reasonable when this function is called.  */)
   struct window *w, *r, *s;
   struct frame *f;
   Lisp_Object sibling, pwindow, swindow IF_LINT (= Qnil), delta;
-  ptrdiff_t startpos IF_LINT (= 0);
+  ptrdiff_t startpos IF_LINT (= 0), startbyte IF_LINT (= 0);
   int top IF_LINT (= 0), new_top, resize_failed;
 
   w = decode_valid_window (window);
@@ -2791,6 +2782,7 @@ window-start value is reasonable when this function is called.  */)
   if (!NILP (w->buffer))
     {
       startpos = marker_position (w->start);
+      startbyte = marker_byte_position (w->start);
       top = WINDOW_TOP_EDGE_LINE (w)
        - FRAME_TOP_MARGIN (XFRAME (WINDOW_FRAME (w)));
       /* Make sure WINDOW is the frame's selected window.  */
@@ -2960,7 +2952,7 @@ window-start value is reasonable when this function is called.  */)
          Fset_buffer (w->buffer);
          /* This computation used to temporarily move point, but that
             can have unwanted side effects due to text properties.  */
-         pos = *vmotion (startpos, -top, w);
+         pos = *vmotion (startpos, startbyte, -top, w);
 
          set_marker_both (w->start, w->buffer, pos.bufpos, pos.bytepos);
          w->window_end_valid = 0;
@@ -4757,7 +4749,8 @@ window_scroll_line_based (Lisp_Object window, int n, int whole, int noerror)
   register Lisp_Object tem;
   int lose;
   Lisp_Object bolp;
-  ptrdiff_t startpos;
+  ptrdiff_t startpos = marker_position (w->start);
+  ptrdiff_t startbyte = marker_byte_position (w->start);
   Lisp_Object original_pos = Qnil;
 
   /* If scrolling screen-fulls, compute the number of lines to
@@ -4765,8 +4758,6 @@ window_scroll_line_based (Lisp_Object window, int n, int whole, int noerror)
   if (whole)
     n *= max (1, ht - next_screen_context_lines);
 
-  startpos = marker_position (w->start);
-
   if (!NILP (Vscroll_preserve_screen_position))
     {
       if (window_scroll_preserve_vpos <= 0
@@ -4774,10 +4765,8 @@ window_scroll_line_based (Lisp_Object window, int n, int whole, int noerror)
          || NILP (Fget (KVAR (current_kboard, Vlast_command), Qscroll_command)))
        {
          struct position posit
-           = *compute_motion (startpos, 0, 0, 0,
-                              PT, ht, 0,
-                              -1, w->hscroll,
-                              0, w);
+           = *compute_motion (startpos, startbyte, 0, 0, 0,
+                              PT, ht, 0, -1, w->hscroll, 0, w);
          window_scroll_preserve_vpos = posit.vpos;
          window_scroll_preserve_hpos = posit.hpos + w->hscroll;
        }
@@ -4793,9 +4782,10 @@ window_scroll_line_based (Lisp_Object window, int n, int whole, int noerror)
     {
       Fvertical_motion (make_number (- (ht / 2)), window);
       startpos = PT;
+      startbyte = PT_BYTE;
     }
 
-  SET_PT (startpos);
+  SET_PT_BOTH (startpos, startbyte);
   lose = n < 0 && PT == BEGV;
   Fvertical_motion (make_number (n), window);
   pos = PT;
@@ -5330,7 +5320,7 @@ and redisplay normally--don't erase and redraw the frame.  */)
 
          iarg = max (iarg, this_scroll_margin);
 
-         pos = *vmotion (PT, -iarg, w);
+         pos = *vmotion (PT, PT_BYTE, -iarg, w);
          charpos = pos.bufpos;
          bytepos = pos.bytepos;
        }
@@ -5349,7 +5339,7 @@ and redisplay normally--don't erase and redraw the frame.  */)
       iarg = clip_to_bounds (this_scroll_margin, iarg,
                             ht - this_scroll_margin - 1);
 
-      pos = *vmotion (PT, - iarg, w);
+      pos = *vmotion (PT, PT_BYTE, - iarg, w);
       charpos = pos.bufpos;
       bytepos = pos.bytepos;
     }