1 files changed, 81 insertions, 0 deletions
diff --git a/lib/libc/locale/mbrtowc.c b/lib/libc/locale/mbrtowc.c
new file mode 100644
index 0000000..a1b960c
--- /dev/null
+++ b/lib/libc/locale/mbrtowc.c
@@ -0,0 +1,81 @@
+/*-
+ * Copyright (c) 2002 Tim J. Robbins.
+ * 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <errno.h>
+#include <rune.h>
+#include <stdlib.h>
+#include <wchar.h>
+
+size_t
+mbrtowc(wchar_t *__restrict pwc, const char *__restrict s, size_t n,
+    mbstate_t *__restrict ps __unused)
+{
+        const char *e;
+        rune_t r;
+
+	if (s == NULL) {
+		pwc = NULL;
+		s = "";
+		n = 1;
+	}
+
+	if (*s == '\0') {
+		if (pwc != NULL)
+			*pwc = L'\0';
+		return (0);
+	}
+
+	if ((r = sgetrune(s, n, &e)) == _INVALID_RUNE) {
+		/*
+		 * The design of sgetrune() doesn't give us any way to tell
+		 * between incomplete and invalid multibyte sequences.
+		 */
+
+		if (n >= (size_t)MB_CUR_MAX) {
+			/*
+			 * If we have been supplied with at least MB_CUR_MAX
+			 * bytes and still cannot find a valid character, the
+			 * data must be invalid.
+			 */
+			errno = EILSEQ;
+			return ((size_t)-1);
+		}
+
+		/*
+		 * .. otherwise, it's an incomplete character or an invalid
+		 * character we cannot detect yet.
+		 */
+		return ((size_t)-2);
+	}
+
+	if (pwc != NULL)
+		*pwc = (wchar_t)r;
+
+	return ((size_t)(e - s));
+}