X-Git-Url: https://ncurses.scripts.mit.edu/?p=ncurses.git;a=blobdiff_plain;f=ncurses%2Fbase%2Flib_ungetch.c;h=4ee9119e5c164425f6265c01fc8ae6be0dbe8c4e;hp=63a14cff7594b0fbcbf612eb24fae6e0658c7361;hb=603f0cb25b7acc8f04f4b18d2a2fe6f90039829a;hpb=3a0d9d27e0cf115ff9dcc6163c251bccaa62bd7d

diff --git a/ncurses/base/lib_ungetch.c b/ncurses/base/lib_ungetch.c
index 63a14cff..4ee9119e 100644
--- a/ncurses/base/lib_ungetch.c
+++ b/ncurses/base/lib_ungetch.c
@@ -1,5 +1,5 @@
 /****************************************************************************
- * Copyright (c) 1998-2008,2009 Free Software Foundation, Inc.              *
+ * Copyright (c) 1998-2011,2012 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            *
@@ -42,7 +42,7 @@
 
 #include <curses.priv.h>
 
-MODULE_ID("$Id: lib_ungetch.c,v 1.14 2009/10/24 22:12:21 tom Exp $")
+MODULE_ID("$Id: lib_ungetch.c,v 1.16 2012/08/04 17:38:53 tom Exp $")
 
 #include <fifo_defs.h>
 
@@ -64,13 +64,14 @@ safe_ungetch(SCREEN *sp, int ch)
 
     T((T_CALLED("ungetch(%p,%s)"), (void *) sp, _nc_tracechar(sp, ch)));
 
-    if (tail != -1) {
-	if (head == -1) {
+    if (sp != 0 && tail >= 0) {
+	if (head < 0) {
 	    head = 0;
 	    t_inc();
 	    peek = tail;	/* no raw keys */
-	} else
+	} else {
 	    h_dec();
+	}
 
 	sp->_fifo[head] = ch;
 	T(("ungetch %s ok", _nc_tracechar(sp, ch)));