ncurses 6.1 - patch 20200118

[ncurses.git] / ncurses / base / lib_erase.c

diff --git a/ncurses/base/lib_erase.c b/ncurses/base/lib_erase.c
index 1e4237bf8056c565ab02f24d1bdad629d43e831e..6bac1ba1017889f6764d56f4c6c39a3ff7f6eafc 100644 (file)
--- a/ncurses/base/lib_erase.c
+++ b/ncurses/base/lib_erase.c
@@ -1,5 +1,5 @@
 /****************************************************************************
- * Copyright (c) 1998 Free Software Foundation, Inc.                        *
+ * Copyright (c) 1998-2009,2016 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            *
@@ -29,9 +29,9 @@
 /****************************************************************************
  *  Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995               *
  *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
+ *     and: Thomas E. Dickey                        1996-on                 *
  ****************************************************************************/
 
-
 /*
 **     lib_erase.c
 **
@@ -41,33 +41,56 @@
 
 #include <curses.priv.h>
 
-MODULE_ID("$Id: lib_erase.c,v 1.11 1998/02/11 12:13:54 tom Exp $")
+MODULE_ID("$Id: lib_erase.c,v 1.18 2016/05/28 23:11:26 tom Exp $")
 
-int  werase(WINDOW     *win)
+NCURSES_EXPORT(int)
+werase(WINDOW *win)
 {
-int     code = ERR;
-int    y;
-chtype blank;
-chtype *sp, *end, *start;
+    int code = ERR;
+    NCURSES_CH_T blank;
+    NCURSES_CH_T *start;
+
+    T((T_CALLED("werase(%p)"), (void *) win));
+
+    if (win) {
+       NCURSES_CH_T *sp;
+       int y;
 
-       T((T_CALLED("werase(%p)"), win));
+       blank = win->_nc_bkgd;
+       for (y = 0; y <= win->_maxy; y++) {
+           NCURSES_CH_T *end;
 
-       if (win) {
-         blank = _nc_background(win);
-         for (y = 0; y <= win->_maxy; y++) {
            start = win->_line[y].text;
            end = &start[win->_maxx];
-           
+
+           /*
+            * If this is a derived window, we have to handle the case where
+            * a multicolumn character extends into the window that we are
+            * erasing.
+            */
+           if_WIDEC({
+               if (isWidecExt(start[0])) {
+                   int x = (win->_parent != 0) ? (win->_begx) : 0;
+                   while (x-- > 0) {
+                       if (isWidecBase(start[-1])) {
+                           --start;
+                           break;
+                       }
+                       --start;
+                   }
+               }
+           });
+
            for (sp = start; sp <= end; sp++)
-             *sp = blank;
-           
+               *sp = blank;
+
            win->_line[y].firstchar = 0;
            win->_line[y].lastchar = win->_maxx;
-         }
-         win->_curx = win->_cury = 0;
-         win->_flags &= ~_WRAPPED;
-         _nc_synchook(win);
-         code = OK;
        }
-       returnCode(code);
+       win->_curx = win->_cury = 0;
+       win->_flags &= ~_WRAPPED;
+       _nc_synchook(win);
+       code = OK;
+    }
+    returnCode(code);
 }