* 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):
Adjust users.
* window.c (wset_scroll_bar_width): Remove.
(make_window): Initialize scroll_bar_width.
(Fsplit_window_internal): Use direct assignment.
(Fset_window_configuration, save_window_save):
Convert Lisp_Object to integer and back where appropriate.
(Fset_window_scroll_bars): Adjust user.  Return t if any scroll
bar was actually changed, and mention this in docstring.

3 files changed, 36 insertions, 27 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index d89f702a2aa..7081236ec65 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,17 @@
+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):
+        Adjust users.
+        * window.c (wset_scroll_bar_width): Remove.
+        (make_window): Initialize scroll_bar_width.
+        (Fsplit_window_internal): Use direct assignment.
+        (Fset_window_configuration, save_window_save):
+        Convert Lisp_Object to integer and back where appropriate.
+        (Fset_window_scroll_bars): Adjust user.  Return t if any scroll
+        bar was actually changed, and mention this in docstring.
+
 2013-08-13  Paul Eggert  <eggert@cs.ucla.edu>
 
         * decompress.c: Minor simplifications.
diff --git a/src/window.c b/src/window.c
index f9084e6c05f..7b2e9b08881 100644
--- a/src/window.c
+++ b/src/window.c
@@ -181,11 +181,6 @@ wset_pointm (struct window *w, Lisp_Object val)
   w->pointm = val;
 }
 static void
-wset_scroll_bar_width (struct window *w, Lisp_Object val)
-{
-  w->scroll_bar_width = val;
-}
-static void
 wset_start (struct window *w, Lisp_Object val)
 {
   w->start = val;
@@ -3461,6 +3456,7 @@ make_window (void)
   w->left_fringe_width = w->right_fringe_width = -1;
   w->phys_cursor_type = -1;
   w->phys_cursor_width = -1;
+  w->scroll_bar_width = -1;
   w->column_number_displayed = -1;
 
   /* Reset window_list.  */
@@ -3931,7 +3927,7 @@ set correctly.  See the code of `split-window' for how this is done.  */)
   n->left_fringe_width = r->left_fringe_width;
   n->right_fringe_width = r->right_fringe_width;
   n->fringes_outside_margins = r->fringes_outside_margins;
-  wset_scroll_bar_width (n, r->scroll_bar_width);
+  n->scroll_bar_width = r->scroll_bar_width;
   wset_vertical_scroll_bar_type (n, r->vertical_scroll_bar_type);
 
   /* Directly assign orthogonal coordinates and sizes.  */
@@ -5674,7 +5670,7 @@ the return value is nil.  Otherwise the value is t.  */)
           w->left_fringe_width = XINT (p->left_fringe_width);
           w->right_fringe_width = XINT (p->right_fringe_width);
           w->fringes_outside_margins = !NILP (p->fringes_outside_margins);
-          wset_scroll_bar_width (w, p->scroll_bar_width);
+          w->scroll_bar_width = XINT (p->scroll_bar_width);
           wset_vertical_scroll_bar_type (w, p->vertical_scroll_bar_type);
           wset_dedicated (w, p->dedicated);
           wset_combination_limit (w, p->combination_limit);
@@ -5975,7 +5971,7 @@ save_window_save (Lisp_Object window, struct Lisp_Vector *vector, int i)
       p->left_fringe_width = make_number (w->left_fringe_width);
       p->right_fringe_width = make_number (w->right_fringe_width);
       p->fringes_outside_margins = w->fringes_outside_margins ? Qt : Qnil;
-      p->scroll_bar_width = w->scroll_bar_width;
+      p->scroll_bar_width = make_number (w->scroll_bar_width);
       p->vertical_scroll_bar_type = w->vertical_scroll_bar_type;
       p->dedicated = w->dedicated;
       p->combination_limit = w->combination_limit;
@@ -6263,18 +6259,17 @@ 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.  */)
-  (Lisp_Object window, Lisp_Object width, Lisp_Object vertical_type, Lisp_Object horizontal_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)
 {
   struct window *w = decode_live_window (window);
+  int iwidth = (NILP (width) ? -1 : (CHECK_NATNUM (width), XINT (width)));
 
-  if (!NILP (width))
-    {
-      CHECK_RANGED_INTEGER (width, 0, INT_MAX);
-
-      if (XINT (width) == 0)
-        vertical_type = Qnil;
-    }
+  if (iwidth == 0)
+    vertical_type = Qnil;
 
   if (!(NILP (vertical_type)
         || EQ (vertical_type, Qleft)
@@ -6282,10 +6277,10 @@ Fourth parameter HORIZONTAL-TYPE is currently unused.  */)
         || EQ (vertical_type, Qt)))
     error ("Invalid type of vertical scroll bar");
 
-  if (!EQ (w->scroll_bar_width, width)
+  if (w->scroll_bar_width != iwidth
       || !EQ (w->vertical_scroll_bar_type, vertical_type))
     {
-      wset_scroll_bar_width (w, width);
+      w->scroll_bar_width = iwidth;
       wset_vertical_scroll_bar_type (w, vertical_type);
 
       adjust_window_margins (w);
@@ -6295,6 +6290,7 @@ Fourth parameter HORIZONTAL-TYPE is currently unused.  */)
 
       ++windows_or_buffers_changed;
       adjust_glyphs (XFRAME (WINDOW_FRAME (w)));
+      return Qt;
     }
 
   return Qnil;
diff --git a/src/window.h b/src/window.h
index 9d41a14cd23..823fe678c43 100644
--- a/src/window.h
+++ b/src/window.h
@@ -141,10 +141,6 @@ struct window
        it yet, or if the frame doesn't have any scroll bars, this is nil.  */
     Lisp_Object vertical_scroll_bar;
 
-    /* Pixel width of scroll bars.
-       A value of nil or t means use frame values.  */
-    Lisp_Object scroll_bar_width;
-
     /* Type of vertical scroll bar.  A value of nil means
        no scroll bar.  A value of t means use frame value.  */
     Lisp_Object vertical_scroll_bar_type;
@@ -269,6 +265,10 @@ struct window
     int left_margin_cols;
     int right_margin_cols;
 
+    /* Pixel width of scroll bars.
+       A value of -1 means use frame values.  */
+    int scroll_bar_width;
+
     /* Non-zero if this window is a minibuffer window.  */
     unsigned mini : 1;
 
@@ -695,8 +695,7 @@ wset_next_buffers (struct window *w, Lisp_Object val)
    nonzero.  */
 
 #define WINDOW_CONFIG_SCROLL_BAR_WIDTH(w)               \
-  (INTEGERP (w->scroll_bar_width)                       \
-   ? XFASTINT (w->scroll_bar_width)                     \
+  (w->scroll_bar_width >= 0 ? w->scroll_bar_width       \
    : FRAME_CONFIG_SCROLL_BAR_WIDTH (WINDOW_XFRAME (w)))
 
 /* Width that a scroll bar in window W should have, if there is one.
@@ -704,8 +703,8 @@ wset_next_buffers (struct window *w, Lisp_Object val)
    this is still nonzero.  */
 
 #define WINDOW_CONFIG_SCROLL_BAR_COLS(w)                \
-  (INTEGERP (w->scroll_bar_width)                       \
-   ? ((XFASTINT (w->scroll_bar_width)                   \
+  (w->scroll_bar_width >= 0                             \
+   ? ((w->scroll_bar_width                              \
        + WINDOW_FRAME_COLUMN_WIDTH (w) - 1)             \
       / WINDOW_FRAME_COLUMN_WIDTH (w))                  \
    : FRAME_CONFIG_SCROLL_BAR_COLS (WINDOW_XFRAME (w)))