1 files changed, 101 insertions, 0 deletions
diff --git a/Utilities/cmpdcurses/pdcurses/scroll.c b/Utilities/cmpdcurses/pdcurses/scroll.c
new file mode 100644
index 0000000000..ffe8d0d94a
--- /dev/null
+++ b/Utilities/cmpdcurses/pdcurses/scroll.c
@@ -0,0 +1,101 @@
+/* PDCurses */
+
+#include <curspriv.h>
+
+/*man-start**************************************************************
+
+scroll
+------
+
+### Synopsis
+
+    int scroll(WINDOW *win);
+    int scrl(int n);
+    int wscrl(WINDOW *win, int n);
+
+### Description
+
+   scroll() causes the window to scroll up one line. This involves
+   moving the lines in the window data strcture.
+
+   With a positive n, scrl() and wscrl() scroll the window up n lines
+   (line i + n becomes i); otherwise they scroll the window down n
+   lines.
+
+   For these functions to work, scrolling must be enabled via
+   scrollok(). Note also that scrolling is not allowed if the supplied
+   window is a pad.
+
+### Return Value
+
+   All functions return OK on success and ERR on error.
+
+### Portability
+                             X/Open  ncurses  NetBSD
+    scroll                      Y       Y       Y
+    scrl                        Y       Y       Y
+    wscrl                       Y       Y       Y
+
+**man-end****************************************************************/
+
+int wscrl(WINDOW *win, int n)
+{
+    int i, l, dir, start, end;
+    chtype blank, *temp;
+
+    /* Check if window scrolls. Valid for window AND pad */
+
+    if (!win || !win->_scroll || !n)
+        return ERR;
+
+    blank = win->_bkgd;
+
+    if (n > 0)
+    {
+        start = win->_tmarg;
+        end = win->_bmarg;
+        dir = 1;
+    }
+    else
+    {
+        start = win->_bmarg;
+        end = win->_tmarg;
+        dir = -1;
+    }
+
+    for (l = 0; l < (n * dir); l++)
+    {
+        temp = win->_y[start];
+
+        /* re-arrange line pointers */
+
+        for (i = start; i != end; i += dir)
+            win->_y[i] = win->_y[i + dir];
+
+        win->_y[end] = temp;
+
+        /* make a blank line */
+
+        for (i = 0; i < win->_maxx; i++)
+            *temp++ = blank;
+    }
+
+    touchline(win, win->_tmarg, win->_bmarg - win->_tmarg + 1);
+
+    PDC_sync(win);
+    return OK;
+}
+
+int scrl(int n)
+{
+    PDC_LOG(("scrl() - called\n"));
+
+    return wscrl(stdscr, n);
+}
+
+int scroll(WINDOW *win)
+{
+    PDC_LOG(("scroll() - called\n"));
+
+    return wscrl(win, 1);
+}