ncurses 5.6 - patch 20071222
[ncurses.git] / ncurses / base / lib_erase.c
index 5e397312ffe35b747c0c3df6ad81acb914631a6e..2566e8b39820a260c0ff0f271d3d0189e0f14a0a 100644 (file)
@@ -29,6 +29,7 @@
 /****************************************************************************
  *  Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995               *
  *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
 /****************************************************************************
  *  Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995               *
  *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
+ *     and: Thomas E. Dickey                        1996-on                 *
  ****************************************************************************/
 
 /*
  ****************************************************************************/
 
 /*
@@ -40,7 +41,7 @@
 
 #include <curses.priv.h>
 
 
 #include <curses.priv.h>
 
-MODULE_ID("$Id: lib_erase.c,v 1.15 2001/12/19 01:06:13 tom Exp $")
+MODULE_ID("$Id: lib_erase.c,v 1.16 2005/10/30 00:36:36 tom Exp $")
 
 NCURSES_EXPORT(int)
 werase(WINDOW *win)
 
 NCURSES_EXPORT(int)
 werase(WINDOW *win)
@@ -58,6 +59,24 @@ werase(WINDOW *win)
            start = win->_line[y].text;
            end = &start[win->_maxx];
 
            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;
 
            for (sp = start; sp <= end; sp++)
                *sp = blank;