/****************************************************************************
- * Copyright (c) 1998-2007,2008 Free Software Foundation, Inc. *
+ * Copyright 2020 Thomas E. Dickey *
+ * Copyright 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 *
* Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995 *
* and: Eric S. Raymond <esr@snark.thyrsus.com> *
* and: Thomas E. Dickey 1996-on *
+ * and: Juergen Pfeifer 2009 *
****************************************************************************/
/*
#include <curses.priv.h>
-MODULE_ID("$Id: lib_ungetch.c,v 1.10 2008/05/03 20:20:58 tom Exp $")
+MODULE_ID("$Id: lib_ungetch.c,v 1.17 2020/02/02 23:34:34 tom Exp $")
#include <fifo_defs.h>
int i;
T(("head = %d, tail = %d, peek = %d", head, tail, peek));
for (i = 0; i < 10; i++)
- T(("char %d = %s", i, _tracechar(sp->_fifo[i])));
+ T(("char %d = %s", i, _nc_tracechar(sp, sp->_fifo[i])));
}
#endif /* TRACE */
NCURSES_EXPORT(int)
-_nc_ungetch(SCREEN *sp, int ch)
+safe_ungetch(SCREEN *sp, int ch)
{
int rc = ERR;
- if (tail != -1) {
- if (head == -1) {
+ T((T_CALLED("ungetch(%p,%s)"), (void *) sp, _nc_tracechar(sp, ch)));
+
+ 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", _tracechar(ch)));
+ T(("ungetch %s ok", _nc_tracechar(sp, ch)));
#ifdef TRACE
if (USE_TRACEF(TRACE_IEVENT)) {
_nc_fifo_dump(sp);
#endif
rc = OK;
}
- return rc;
+ returnCode(rc);
}
NCURSES_EXPORT(int)
ungetch(int ch)
{
- T((T_CALLED("ungetch(%s)"), _tracechar(ch)));
- returnCode(_nc_ungetch(SP, ch));
+ return safe_ungetch(CURRENT_SCREEN, ch);
}