1 files changed, 74 insertions, 0 deletions
diff --git a/usr/src/lib/libc/port/stdio/ungetc.c b/usr/src/lib/libc/port/stdio/ungetc.c
new file mode 100644
index 0000000000..dfa831e977
--- /dev/null
+++ b/usr/src/lib/libc/port/stdio/ungetc.c
@@ -0,0 +1,74 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License, Version 1.0 only
+ * (the "License").  You may not use this file except in compliance
+ * with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+/*
+ * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#pragma ident	"%Z%%M%	%I%	%E% SMI"
+
+/*	Copyright (c) 1988 AT&T	*/
+/*	  All Rights Reserved  	*/
+
+
+#include "synonyms.h"
+#include "file64.h"
+#include "mtlib.h"
+#include <sys/types.h>
+#include <stdio.h>
+#include <thread.h>
+#include <synch.h>
+#include "stdiom.h"
+
+int _ungetc_unlocked(int c, FILE *iop);
+
+int
+ungetc(int c, FILE *iop)
+{
+	FLOCKRETURN(iop, _ungetc_unlocked(c, iop))
+}
+
+/*
+ * Called internally by the library (instead of the safe "ungetc") when
+ * iop->_lock is already held at a higher level - required since we do not
+ * have recursive locks.
+ */
+int
+_ungetc_unlocked(int c, FILE *iop)
+{
+	if (c == EOF)
+		return (EOF);
+	if (iop->_ptr <= iop->_base) {
+		if (iop->_base == 0) {
+			if (_findbuf(iop) == 0)
+				return (EOF);
+		} else if (iop->_ptr <= iop->_base - PUSHBACK)
+			return (EOF);
+	}
+	if ((iop->_flag & _IOREAD) == 0) /* basically a no-op on write stream */
+		++iop->_ptr;
+	if (*--iop->_ptr != (unsigned char) c)
+		*iop->_ptr = (unsigned char) c;  /* was *--iop->_ptr = c; */
+	++iop->_cnt;
+	iop->_flag &= ~_IOEOF;
+	return (c);
+}