[*] Initial commit

lonetix/utf/utflen.c

@@ -0,0 +1,53 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+
+/**
+ * \file utf/utflen.c
+ *
+ * Implements `utflen()`.
+ *
+ * \copyright The DoubleFourteen Code Forge (C) All Rights Reserved
+ * \author    Lorenzo Cogotti
+ */
+
+/*
+ * This work is derived from Plan 9 libutf, see utf/utf.h for details.
+ * Original license terms follow:
+ *
+ * The authors of this software are Rob Pike and Ken Thompson.
+ *              Copyright (c) 2002 by Lucent Technologies.
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose without fee is hereby granted, provided that this entire notice
+ * is included in all copies of any software which is or includes a copy
+ * or modification of this software and in all copies of the supporting
+ * documentation for such software.
+ * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED
+ * WARRANTY.  IN PARTICULAR, NEITHER THE AUTHORS NOR LUCENT TECHNOLOGIES MAKE
+ * ANY REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY
+ * OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
+ *
+ * The original libutf library is available at: https://9fans.github.io/plan9port/unix/libutf.tgz
+ */
+
+#include "utf/utf.h"
+
+size_t utflen(const char *s)
+{
+	size_t n = 0;
+
+	while (TRUE) {
+		Rune r = *(const Uint8 *) s;
+
+		if (r < RUNE_SELF) {
+			if (r == '\0')
+				break;
+
+			s++;
+		} else {
+			s += chartorune(&r, s);
+		}
+
+		n++;
+	}
+
+	return n;
+}