(DOZ): new macro: difference or zero.

Use DOZ where appropriate.

Signed-off-by: Andrew Borodin <aborodin@vmail.ru>

lib/util.h

@@ -54,6 +54,9 @@
  */
 #define _GL_CMP(n1, n2) (((n1) > (n2)) - ((n1) < (n2)))
 
+/* Difference of zero */
+#define DOZ(a, b) ((a) > (b) ? (a) - (b) : 0)
+
 /*** enums ***************************************************************************************/
 
 /* Pathname canonicalization */

lib/widget/listbox.c

@@ -639,8 +639,8 @@ listbox_select_last (WListbox * l)
 
     length = listbox_get_length (l);
 
-    l->pos = length > 0 ? length - 1 : 0;
+    l->pos = DOZ (length, 1);
-    l->top = length > lines ? length - lines : 0;
+    l->top = DOZ (length, lines);
 }
 
 /* --------------------------------------------------------------------------------------------- */

src/viewer/ascii.c

@@ -1038,7 +1038,7 @@ mcview_ascii_moveto_eol (WView * view)
         /* Get the width of the topmost paragraph. */
         mcview_state_machine_init (&state, view->dpy_start);
         mcview_display_line (view, &state, -1, NULL, &linewidth);
-        view->dpy_text_column = mcview_offset_doz (linewidth, (off_t) view->data_area.width);
+        view->dpy_text_column = DOZ (linewidth, (off_t) view->data_area.width);
     }
 }
 

src/viewer/display.c

@@ -268,8 +268,8 @@ mcview_compute_areas (WView * view)
 
     view_area.top = view->dpy_frame_size;
     view_area.left = view->dpy_frame_size;
-    view_area.height = mcview_dimen_doz (WIDGET (view)->lines, 2 * view->dpy_frame_size);
+    view_area.height = DOZ ((screen_dimen) WIDGET (view)->lines, 2 * view->dpy_frame_size);
-    view_area.width = mcview_dimen_doz (WIDGET (view)->cols, 2 * view->dpy_frame_size);
+    view_area.width = DOZ ((screen_dimen) WIDGET (view)->cols, 2 * view->dpy_frame_size);
 
     /* Most coordinates of the areas equal those of the whole viewer */
     view->status_area = view_area;

src/viewer/inlines.h

@@ -18,15 +18,6 @@
 
 /*** inline functions ****************************************************************************/
 
-/* difference or zero */
-static inline off_t
-mcview_offset_doz (off_t a, off_t b)
-{
-    return (a >= b) ? a - b : 0;
-}
-
-/* --------------------------------------------------------------------------------------------- */
-
 static inline off_t
 mcview_offset_rounddown (off_t a, off_t b)
 {
@@ -36,15 +27,6 @@ mcview_offset_rounddown (off_t a, off_t b)
 
 /* --------------------------------------------------------------------------------------------- */
 
-/* difference or zero */
-static inline screen_dimen
-mcview_dimen_doz (screen_dimen a, screen_dimen b)
-{
-    return (a >= b) ? a - b : 0;
-}
-
-/* --------------------------------------------------------------------------------------------- */
-
 /* {{{ Simple Primitive Functions for WView }}} */
 static inline gboolean
 mcview_is_in_panel (WView * view)

src/viewer/move.c

@@ -118,7 +118,7 @@ mcview_move_up (WView * view, off_t lines)
             view->hex_cursor -= bytes;
             if (view->hex_cursor < view->dpy_start)
             {
-                view->dpy_start = mcview_offset_doz (view->dpy_start, bytes);
+                view->dpy_start = DOZ (view->dpy_start, bytes);
                 view->dpy_paragraph_skip_lines = 0;
                 view->dpy_wrap_dirty = TRUE;
             }
@@ -148,7 +148,7 @@ mcview_move_down (WView * view, off_t lines)
     {
         off_t i, limit;
 
-        limit = mcview_offset_doz (last_byte, (off_t) view->bytes_per_line);
+        limit = DOZ (last_byte, (off_t) view->bytes_per_line);
 
         for (i = 0; i < lines && view->hex_cursor < limit; i++)
         {
@@ -189,7 +189,7 @@ mcview_move_left (WView * view, off_t columns)
                 view->hexedit_lownibble = !view->hexedit_lownibble;
     }
     else if (!view->mode_flags.wrap)
-        view->dpy_text_column = mcview_offset_doz (view->dpy_text_column, columns);
+        view->dpy_text_column = DOZ (view->dpy_text_column, columns);
     mcview_movement_fixups (view, FALSE);
 }
 
@@ -203,7 +203,8 @@ mcview_move_right (WView * view, off_t columns)
         off_t last_byte;
         off_t old_cursor = view->hex_cursor;
 
-        last_byte = mcview_offset_doz (mcview_get_filesize (view), 1);
+        last_byte = mcview_get_filesize (view);
+        last_byte = DOZ (last_byte, 1);
 
         g_assert (columns == 1);
 
@@ -252,7 +253,7 @@ mcview_moveto_bottom (WView * view)
 
     if (view->mode_flags.hex)
     {
-        view->hex_cursor = mcview_offset_doz (filesize, 1);
+        view->hex_cursor = DOZ (filesize, 1);
         mcview_movement_fixups (view, TRUE);
     }
     else
@@ -302,7 +303,7 @@ mcview_moveto_eol (WView * view)
         else
         {
             filesize = mcview_get_filesize (view);
-            view->hex_cursor = mcview_offset_doz (filesize, 1);
+            view->hex_cursor = DOZ (filesize, 1);
         }
     }
     else