1 files changed, 97 insertions, 0 deletions
diff --git a/lib/libc/stdio/vswprintf.c b/lib/libc/stdio/vswprintf.c
new file mode 100644
index 00000000000..4d10976edd4
--- /dev/null
+++ b/lib/libc/stdio/vswprintf.c
@@ -0,0 +1,97 @@
+/*	$OpenBSD: vswprintf.c,v 1.1 2011/04/24 07:46:58 stsp Exp $	*/
+/*	$NetBSD: vswprintf.c,v 1.1 2005/05/14 23:51:02 christos Exp $	*/
+
+/*
+ * Copyright (c) 1997 Todd C. Miller <Todd.Miller@courtesan.com>
+ * 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.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED ``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 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.
+ */
+
+#include <sys/cdefs.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <wchar.h>
+#include <stdarg.h>
+#include "local.h"
+
+int
+vswprintf(wchar_t * __restrict s, size_t n, const wchar_t * __restrict fmt,
+    __va_list ap)
+{
+	mbstate_t mbs;
+	FILE f;
+	char *mbp;
+	int ret, sverrno;
+	size_t nwc;
+	struct __sfileext fext;
+
+	if (n == 0) {
+		errno = EINVAL;
+		return (-1);
+	}
+
+	_FILEEXT_SETUP(&f, &fext);
+	f._file = -1;
+	f._flags = __SWR | __SSTR | __SALC;
+	f._bf._base = f._p = (unsigned char *)malloc(128);
+	if (f._bf._base == NULL) {
+		errno = ENOMEM;
+		return (-1);
+	}
+	f._bf._size = f._w = 127;		/* Leave room for the NUL */
+	ret = __vfwprintf(&f, fmt, ap);
+	if (ret < 0) {
+		sverrno = errno;
+		free(f._bf._base);
+		errno = sverrno;
+		return (-1);
+	}
+	if (ret == 0) {
+		s[0] = L'\0';
+		free(f._bf._base);
+		return (0);
+	}
+	*f._p = '\0';
+	mbp = (char *)f._bf._base;
+	/*
+	 * XXX Undo the conversion from wide characters to multibyte that
+	 * fputwc() did in __vfwprintf().
+	 */
+	bzero(&mbs, sizeof(mbs));
+	nwc = mbsrtowcs(s, (const char **)&mbp, n, &mbs);
+	free(f._bf._base);
+	if (nwc == (size_t)-1) {
+		errno = EILSEQ;
+		return (-1);
+	}
+	if (nwc == n) {
+		s[n - 1] = L'\0';
+		errno = EOVERFLOW;
+		return (-1);
+	}
+
+	return (ret);
+}