1 files changed, 70 insertions, 0 deletions
diff --git a/lib/libc/stdio/ungetwc.c b/lib/libc/stdio/ungetwc.c
new file mode 100644
index 00000000000..8bd30168130
--- /dev/null
+++ b/lib/libc/stdio/ungetwc.c
@@ -0,0 +1,70 @@
+/*	$OpenBSD: ungetwc.c,v 1.1 2005/06/17 20:40:32 espie Exp $	*/
+/* $NetBSD: ungetwc.c,v 1.2 2003/01/18 11:29:59 thorpej Exp $ */
+
+/*-
+ * Copyright (c)2001 Citrus Project,
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $Citrus$
+ */
+
+#include <errno.h>
+#include <stdio.h>
+#include <wchar.h>
+#include "local.h"
+
+wint_t
+ungetwc(wint_t wc, FILE *fp)
+{
+	struct wchar_io_data *wcio;
+
+	if (wc == WEOF)
+		return WEOF;
+
+	flockfile(fp);
+	_SET_ORIENTATION(fp, 1);
+	/*
+	 * XXX since we have no way to transform a wchar string to
+	 * a char string in reverse order, we can't use ungetc.
+	 */
+	/* XXX should we flush ungetc buffer? */
+
+	wcio = WCIO_GET(fp);
+	if (wcio == 0) {
+		funlockfile(fp);
+		errno = ENOMEM; /* XXX */
+		return WEOF;
+	}
+
+	if (wcio->wcio_ungetwc_inbuf >= WCIO_UNGETWC_BUFSIZE) {
+		funlockfile(fp);
+		return WEOF;
+	}
+
+	wcio->wcio_ungetwc_buf[wcio->wcio_ungetwc_inbuf++] = wc;
+	__sclearerr(fp);
+	funlockfile(fp);
+
+	return wc;
+}