Cleanup window fringes, margins and scroll bars adjustments.

* window.c (set_window_fringes, set_window_margins)
(set_window_scroll_bars, apply_window_adjustment): New functions.
(set_window_buffer, Fset_window_margins, Fset_window_fringes)
(Fset_window_scroll_bars): Use them.

2 files changed, 112 insertions, 95 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 7081236ec65..af088340e3b 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,5 +1,13 @@
 2013-08-14  Dmitry Antipov  <dmantipov@yandex.ru>
 
+        Cleanup window fringes, margins and scroll bars adjustments.
+        * window.c (set_window_fringes, set_window_margins)
+        (set_window_scroll_bars, apply_window_adjustment): New functions.
+        (set_window_buffer, Fset_window_margins, Fset_window_fringes)
+        (Fset_window_scroll_bars): Use them.
+
+2013-08-14  Dmitry Antipov  <dmantipov@yandex.ru>
+
         * window.h (struct window): Convert scroll_bar_width
         from Lisp_Object to integer.  Adjust comment.
         (WINDOW_CONFIG_SCROLL_BAR_WIDTH, WINDOW_CONFIG_SCROLL_BAR_COLS):
diff --git a/src/window.c b/src/window.c
index 7b2e9b08881..d07eed86a1c 100644
--- a/src/window.c
+++ b/src/window.c
@@ -87,6 +87,14 @@ static void window_resize_apply (struct window *, bool);
 static Lisp_Object select_window (Lisp_Object, Lisp_Object, int);
 static void select_window_1 (Lisp_Object, bool);
 
+static struct window *set_window_fringes (struct window *, Lisp_Object,
+                                          Lisp_Object, Lisp_Object);
+static struct window *set_window_margins (struct window *, Lisp_Object,
+                                          Lisp_Object);
+static struct window *set_window_scroll_bars (struct window *, Lisp_Object,
+                                              Lisp_Object, Lisp_Object);
+static void apply_window_adjustment (struct window *);
+
 /* This is the window in which the terminal's cursor should
    be left when nothing is being done with it.  This must
    always be a leaf window, and its buffer is selected by
@@ -3202,28 +3210,14 @@ set_window_buffer (Lisp_Object window, Lisp_Object buffer,
   if (!keep_margins_p)
     {
       /* Set left and right marginal area width etc. from buffer.  */
-
-      /* This may call adjust_window_margins three times, so
-         temporarily disable window margins.  */
-      int save_left = w->left_margin_cols;
-      int save_right = w->right_margin_cols;
-
-      w->left_margin_cols = 0;
-      w->right_margin_cols = 0;
-
-      Fset_window_fringes (window,
-                           BVAR (b, left_fringe_width), BVAR (b, right_fringe_width),
-                           BVAR (b, fringes_outside_margins));
-
-      Fset_window_scroll_bars (window,
-                               BVAR (b, scroll_bar_width),
-                               BVAR (b, vertical_scroll_bar_type), Qnil);
-
-      w->left_margin_cols = save_left;
-      w->right_margin_cols = save_right;
-
-      Fset_window_margins (window,
-                           BVAR (b, left_margin_cols), BVAR (b, right_margin_cols));
+      set_window_fringes (w, BVAR (b, left_fringe_width),
+                          BVAR (b, right_fringe_width),
+                          BVAR (b, fringes_outside_margins));
+      set_window_scroll_bars (w, BVAR (b, scroll_bar_width),
+                              BVAR (b, vertical_scroll_bar_type), Qnil);
+      set_window_margins (w, BVAR (b, left_margin_cols),
+                          BVAR (b, right_margin_cols));
+      apply_window_adjustment (w);
     }
 
   if (run_hooks_p)
@@ -6112,29 +6106,32 @@ saved by this function.  */)
   XSETWINDOW_CONFIGURATION (tem, data);
   return (tem);
 }
+
+/* Called after W's margins, fringes or scroll bars was adjusted.  */
+
+static void
+apply_window_adjustment (struct window *w)
+{
+  eassert (w);
+  adjust_window_margins (w);
+  clear_glyph_matrix (w->current_matrix);
+  w->window_end_valid = 0;
+  windows_or_buffers_changed++;
+  adjust_glyphs (XFRAME (WINDOW_FRAME (w)));
+}
+
 
 /***********************************************************************
                             Marginal Areas
  ***********************************************************************/
 
-DEFUN ("set-window-margins", Fset_window_margins, Sset_window_margins,
-       2, 3, 0,
-       doc: /* Set width of marginal areas of window WINDOW.
-WINDOW must be a live window and defaults to the selected one.
-
-Second arg LEFT-WIDTH specifies the number of character cells to
-reserve for the left marginal area.  Optional third arg RIGHT-WIDTH
-does the same for the right marginal area.  A nil width parameter
-means no margin.
-
-Return t if any margin was actually changed and nil otherwise.  */)
-  (Lisp_Object window, Lisp_Object left_width, Lisp_Object right_width)
+static struct window *
+set_window_margins (struct window *w, Lisp_Object left_width,
+                    Lisp_Object right_width)
 {
-  struct window *w = decode_live_window (window);
   int left, right;
 
   /* FIXME: what about margins that are too wide?  */
-
   left = (NILP (left_width) ? 0
           : (CHECK_NATNUM (left_width), XINT (left_width)));
   right = (NILP (right_width) ? 0
@@ -6144,15 +6141,27 @@ Return t if any margin was actually changed and nil otherwise.  */)
     {
       w->left_margin_cols = left;
       w->right_margin_cols = right;
+      return w;
+    }
+  return NULL;
+}
 
-      adjust_window_margins (w);
+DEFUN ("set-window-margins", Fset_window_margins, Sset_window_margins,
+       2, 3, 0,
+       doc: /* Set width of marginal areas of window WINDOW.
+WINDOW must be a live window and defaults to the selected one.
 
-      ++windows_or_buffers_changed;
-      adjust_glyphs (XFRAME (WINDOW_FRAME (w)));
-      return Qt;
-    }
+Second arg LEFT-WIDTH specifies the number of character cells to
+reserve for the left marginal area.  Optional third arg RIGHT-WIDTH
+does the same for the right marginal area.  A nil width parameter
+means no margin.
 
-  return Qnil;
+Return t if any margin was actually changed and nil otherwise.  */)
+  (Lisp_Object window, Lisp_Object left_width, Lisp_Object right_width)
+{
+  struct window *w = set_window_margins (decode_live_window (window),
+                                         left_width, right_width);
+  return w ? (apply_window_adjustment (w), Qt) : Qnil;
 }
 
 
@@ -6177,25 +6186,10 @@ as nil.  */)
                             Fringes
  ***********************************************************************/
 
-DEFUN ("set-window-fringes", Fset_window_fringes, Sset_window_fringes,
-       2, 4, 0,
-       doc: /* Set the fringe widths of window WINDOW.
-WINDOW must be a live window and defaults to the selected one.
-
-Second arg LEFT-WIDTH specifies the number of pixels to reserve for
-the left fringe.  Optional third arg RIGHT-WIDTH specifies the right
-fringe width.  If a fringe width arg is nil, that means to use the
-frame's default fringe width.  Default fringe widths can be set with
-the command `set-fringe-style'.
-If optional fourth arg OUTSIDE-MARGINS is non-nil, draw the fringes
-outside of the display margins.  By default, fringes are drawn between
-display marginal areas and the text area.
-
-Return t if any fringe was actually changed and nil otherwise.  */)
-  (Lisp_Object window, Lisp_Object left_width,
-   Lisp_Object right_width, Lisp_Object outside_margins)
+static struct window *
+set_window_fringes (struct window *w, Lisp_Object left_width,
+                    Lisp_Object right_width, Lisp_Object outside_margins)
 {
-  struct window *w = decode_live_window (window);
   int left, right, outside = !NILP (outside_margins);
 
   left = (NILP (left_width) ? -1
@@ -6212,18 +6206,33 @@ Return t if any fringe was actually changed and nil otherwise.  */)
       w->left_fringe_width = left;
       w->right_fringe_width = right;
       w->fringes_outside_margins = outside;
+      return w;
+    }
+  return NULL;
+}
 
-      adjust_window_margins (w);
-
-      clear_glyph_matrix (w->current_matrix);
-      w->window_end_valid = 0;
+DEFUN ("set-window-fringes", Fset_window_fringes, Sset_window_fringes,
+       2, 4, 0,
+       doc: /* Set the fringe widths of window WINDOW.
+WINDOW must be a live window and defaults to the selected one.
 
-      ++windows_or_buffers_changed;
-      adjust_glyphs (XFRAME (WINDOW_FRAME (w)));
-      return Qt;
-    }
+Second arg LEFT-WIDTH specifies the number of pixels to reserve for
+the left fringe.  Optional third arg RIGHT-WIDTH specifies the right
+fringe width.  If a fringe width arg is nil, that means to use the
+frame's default fringe width.  Default fringe widths can be set with
+the command `set-fringe-style'.
+If optional fourth arg OUTSIDE-MARGINS is non-nil, draw the fringes
+outside of the display margins.  By default, fringes are drawn between
+display marginal areas and the text area.
 
-  return Qnil;
+Return t if any fringe was actually changed and nil otherwise.  */)
+  (Lisp_Object window, Lisp_Object left_width,
+   Lisp_Object right_width, Lisp_Object outside_margins)
+{
+  struct window *w
+    = set_window_fringes (decode_live_window (window),
+                          left_width, right_width, outside_margins);
+  return w ? (apply_window_adjustment (w), Qt) : Qnil;
 }
 
 
@@ -6248,24 +6257,10 @@ Value is a list of the form (LEFT-WIDTH RIGHT-WIDTH OUTSIDE-MARGINS).  */)
                             Scroll bars
  ***********************************************************************/
 
-DEFUN ("set-window-scroll-bars", Fset_window_scroll_bars,
-       Sset_window_scroll_bars, 2, 4, 0,
-       doc: /* Set width and type of scroll bars of window WINDOW.
-WINDOW must be a live window and defaults to the selected one.
-
-Second parameter WIDTH specifies the pixel width for the scroll bar;
-this is automatically adjusted to a multiple of the frame column width.
-Third parameter VERTICAL-TYPE specifies the type of the vertical scroll
-bar: left, right, or nil.
-If WIDTH is nil, use the frame's scroll-bar width.
-If VERTICAL-TYPE is t, use the frame's scroll-bar type.
-Fourth parameter HORIZONTAL-TYPE is currently unused.
-
-Return t if scroll bars was actually changed and nil otherwise.  */)
-  (Lisp_Object window, Lisp_Object width,
-   Lisp_Object vertical_type, Lisp_Object horizontal_type)
+static struct window *
+set_window_scroll_bars (struct window *w, Lisp_Object width,
+                        Lisp_Object vertical_type, Lisp_Object horizontal_type)
 {
-  struct window *w = decode_live_window (window);
   int iwidth = (NILP (width) ? -1 : (CHECK_NATNUM (width), XINT (width)));
 
   if (iwidth == 0)
@@ -6282,18 +6277,32 @@ Return t if scroll bars was actually changed and nil otherwise.  */)
     {
       w->scroll_bar_width = iwidth;
       wset_vertical_scroll_bar_type (w, vertical_type);
+      return w;
+    }
+  return NULL;
+}
 
-      adjust_window_margins (w);
-
-      clear_glyph_matrix (w->current_matrix);
-      w->window_end_valid = 0;
+DEFUN ("set-window-scroll-bars", Fset_window_scroll_bars,
+       Sset_window_scroll_bars, 2, 4, 0,
+       doc: /* Set width and type of scroll bars of window WINDOW.
+WINDOW must be a live window and defaults to the selected one.
 
-      ++windows_or_buffers_changed;
-      adjust_glyphs (XFRAME (WINDOW_FRAME (w)));
-      return Qt;
-    }
+Second parameter WIDTH specifies the pixel width for the scroll bar;
+this is automatically adjusted to a multiple of the frame column width.
+Third parameter VERTICAL-TYPE specifies the type of the vertical scroll
+bar: left, right, or nil.
+If WIDTH is nil, use the frame's scroll-bar width.
+If VERTICAL-TYPE is t, use the frame's scroll-bar type.
+Fourth parameter HORIZONTAL-TYPE is currently unused.
 
-  return Qnil;
+Return t if scroll bars was actually changed and nil otherwise.  */)
+  (Lisp_Object window, Lisp_Object width,
+   Lisp_Object vertical_type, Lisp_Object horizontal_type)
+{
+  struct window *w
+    = set_window_scroll_bars (decode_live_window (window),
+                              width, vertical_type, horizontal_type);
+  return w ? (apply_window_adjustment (w), Qt) : Qnil;
 }