]> ncurses.scripts.mit.edu Git - ncurses.git/blobdiff - ncurses/base/lib_scroll.c
ncurses 5.2
[ncurses.git] / ncurses / base / lib_scroll.c
index 197bb221a07c26c63e2f7c586f6852ffad70dae7..c2e3831da2550ace967a7a0432cc05cab973c8a1 100644 (file)
@@ -1,5 +1,5 @@
 /****************************************************************************
- * Copyright (c) 1998 Free Software Foundation, Inc.                        *
+ * Copyright (c) 1998,2000 Free Software Foundation, Inc.                   *
  *                                                                          *
  * Permission is hereby granted, free of charge, to any person obtaining a  *
  * copy of this software and associated documentation files (the            *
@@ -31,8 +31,6 @@
  *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
  ****************************************************************************/
 
-
-
 /*
 **     lib_scroll.c
 **
 
 #include <curses.priv.h>
 
-MODULE_ID("$Id: lib_scroll.c,v 1.16 1998/02/11 12:13:55 tom Exp $")
+MODULE_ID("$Id: lib_scroll.c,v 1.17 2000/04/29 21:10:51 tom Exp $")
 
-void _nc_scroll_window(WINDOW *win, int const n, short const top, short const bottom, chtype blank)
+void
+_nc_scroll_window(WINDOW *win, int const n, NCURSES_SIZE_T const top,
+    NCURSES_SIZE_T const bottom, chtype blank)
 {
-int    line, j;
-size_t to_copy = (size_t)(sizeof(chtype) * (win->_maxx + 1));
-
-       TR(TRACE_MOVE, ("_nc_scroll_window(%p, %d, %d, %d)", win, n, top,bottom)); 
-
-       /*
-        * This used to do a line-text pointer-shuffle instead of text copies.
-        * That (a) doesn't work when the window is derived and doesn't have
-        * its own storage, (b) doesn't save you a lot on modern machines
-        * anyway.  Your typical memcpy implementations are coded in
-        * assembler using a tight BLT loop; for the size of copies we're
-        * talking here, the total execution time is dominated by the one-time
-        * setup cost.  So there is no point in trying to be excessively
-        * clever -- esr.
-        */
-
-       /* shift n lines downwards */
-       if (n < 0) {
-               for (line = bottom; line >= top-n; line--) {
-                       memcpy(win->_line[line].text,
-                              win->_line[line+n].text,
-                              to_copy);
-                       if_USE_SCROLL_HINTS(win->_line[line].oldindex = win->_line[line+n].oldindex);
-               }
-               for (line = top; line < top-n; line++) {
-                       for (j = 0; j <= win->_maxx; j ++)
-                               win->_line[line].text[j] = blank;
-                       if_USE_SCROLL_HINTS(win->_line[line].oldindex = _NEWINDEX);
-               }
-       }
-
-       /* shift n lines upwards */
-       if (n > 0) {
-               for (line = top; line <= bottom-n; line++) {
-                       memcpy(win->_line[line].text,
-                              win->_line[line+n].text,
-                              to_copy);
-                       if_USE_SCROLL_HINTS(win->_line[line].oldindex = win->_line[line+n].oldindex);
-               }
-               for (line = bottom; line > bottom-n; line--) {
-                       for (j = 0; j <= win->_maxx; j ++)
-                               win->_line[line].text[j] = blank;
-                       if_USE_SCROLL_HINTS(win->_line[line].oldindex = _NEWINDEX);
-               }
+    int line, j;
+    size_t to_copy = (size_t) (sizeof(chtype) * (win->_maxx + 1));
+
+    TR(TRACE_MOVE, ("_nc_scroll_window(%p, %d, %d, %d)", win, n, top, bottom));
+
+    /*
+     * This used to do a line-text pointer-shuffle instead of text copies.
+     * That (a) doesn't work when the window is derived and doesn't have
+     * its own storage, (b) doesn't save you a lot on modern machines
+     * anyway.  Your typical memcpy implementations are coded in
+     * assembler using a tight BLT loop; for the size of copies we're
+     * talking here, the total execution time is dominated by the one-time
+     * setup cost.  So there is no point in trying to be excessively
+     * clever -- esr.
+     */
+
+    /* shift n lines downwards */
+    if (n < 0) {
+       for (line = bottom; line >= top - n; line--) {
+           memcpy(win->_line[line].text,
+               win->_line[line + n].text,
+               to_copy);
+           if_USE_SCROLL_HINTS(win->_line[line].oldindex = win->_line[line
+                   + n].oldindex);
+       }
+       for (line = top; line < top - n; line++) {
+           for (j = 0; j <= win->_maxx; j++)
+               win->_line[line].text[j] = blank;
+           if_USE_SCROLL_HINTS(win->_line[line].oldindex = _NEWINDEX);
+       }
+    }
+
+    /* shift n lines upwards */
+    if (n > 0) {
+       for (line = top; line <= bottom - n; line++) {
+           memcpy(win->_line[line].text,
+               win->_line[line + n].text,
+               to_copy);
+           if_USE_SCROLL_HINTS(win->_line[line].oldindex = win->_line[line
+                   + n].oldindex);
+       }
+       for (line = bottom; line > bottom - n; line--) {
+           for (j = 0; j <= win->_maxx; j++)
+               win->_line[line].text[j] = blank;
+           if_USE_SCROLL_HINTS(win->_line[line].oldindex = _NEWINDEX);
        }
-       touchline(win, top, bottom-top+1);
+    }
+    touchline(win, top, bottom - top + 1);
 }
 
 int
 wscrl(WINDOW *win, int n)
 {
-       T((T_CALLED("wscrl(%p,%d)"), win, n));
+    T((T_CALLED("wscrl(%p,%d)"), win, n));
 
-       if (!win || !win->_scroll)
-               returnCode(ERR);
+    if (!win || !win->_scroll)
+       returnCode(ERR);
 
-       if (n == 0)
-               returnCode(OK);
+    if (n == 0)
+       returnCode(OK);
 
-       if ((n > (win->_regbottom - win->_regtop)) || 
-           (-n > (win->_regbottom - win->_regtop)))
-           returnCode(ERR);
+    if ((n > (win->_regbottom - win->_regtop)) ||
+       (-n > (win->_regbottom - win->_regtop)))
+       returnCode(ERR);
 
-       _nc_scroll_window(win, n, win->_regtop, win->_regbottom, _nc_background(win));
+    _nc_scroll_window(win, n, win->_regtop, win->_regbottom, _nc_background(win));
 
-       _nc_synchook(win);
-       returnCode(OK);
+    _nc_synchook(win);
+    returnCode(OK);
 }