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--- /dev/null
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+/* Counting the multibyte characters in a string.
+   Copyright (C) 2007 Free Software Foundation, Inc.
+   Written by Bruno Haible <bruno@clisp.org>, 2007.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software Foundation,
+   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
+
+#include <config.h>
+
+/* Specification.  */
+#include <string.h>
+
+#if HAVE_MBRTOWC
+# include "mbuiter.h"
+#endif
+
+/* Return the number of multibyte characters in the character string STRING.  */
+size_t
+mbslen (const char *string)
+{
+#if HAVE_MBRTOWC
+  if (MB_CUR_MAX > 1)
+    {
+      size_t count;
+      mbui_iterator_t iter;
+
+      count = 0;
+      for (mbui_init (iter, string); mbui_avail (iter); mbui_advance (iter))
+	count++;
+
+      return count;
+    }
+  else
+#endif
+    return strlen (string);
+}