new file mode 100644
--- /dev/null
+++ b/lib/unistr/u-strdup.h
@@ -0,0 +1,41 @@
+/* Copy UTF-8/UTF-16/UTF-32 string.
+   Copyright (C) 1999, 2002, 2006 Free Software Foundation, Inc.
+   Written by Bruno Haible <bruno@clisp.org>, 2002.
+
+   This program is free software; you can redistribute it and/or modify it
+   under the terms of the GNU Library 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library 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 <string.h>
+
+UNIT *
+FUNC (const UNIT *s)
+{
+  size_t n = U_STRLEN (s) + 1;
+  UNIT *dest;
+
+  dest = (UNIT *) malloc (n * sizeof (UNIT));
+  if (dest != NULL)
+    {
+#if 0
+      UNIT *destptr = dest;
+
+      for (; n > 0; n--)
+	*destptr++ = *s++;
+#else
+      memcpy ((char *) dest, (const char *) s, n * sizeof (UNIT));
+#endif
+    }
+  return dest;
+}

new file mode 100644
--- /dev/null
+++ b/lib/unistr/u16-strdup.c
@@ -0,0 +1,28 @@
+/* Copy UTF-16 string.
+   Copyright (C) 1999, 2002, 2006 Free Software Foundation, Inc.
+   Written by Bruno Haible <bruno@clisp.org>, 2002.
+
+   This program is free software; you can redistribute it and/or modify it
+   under the terms of the GNU Library 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library 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 "unistr.h"
+
+#define FUNC u16_strdup
+#define UNIT uint16_t
+#define U_STRLEN u16_strlen
+#include "u-strdup.h"

new file mode 100644
--- /dev/null
+++ b/lib/unistr/u32-strdup.c
@@ -0,0 +1,28 @@
+/* Copy UTF-32 string.
+   Copyright (C) 1999, 2002, 2006 Free Software Foundation, Inc.
+   Written by Bruno Haible <bruno@clisp.org>, 2002.
+
+   This program is free software; you can redistribute it and/or modify it
+   under the terms of the GNU Library 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library 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 "unistr.h"
+
+#define FUNC u32_strdup
+#define UNIT uint32_t
+#define U_STRLEN u32_strlen
+#include "u-strdup.h"

new file mode 100644
--- /dev/null
+++ b/lib/unistr/u8-strdup.c
@@ -0,0 +1,42 @@
+/* Copy UTF-8 string.
+   Copyright (C) 2002, 2006 Free Software Foundation, Inc.
+   Written by Bruno Haible <bruno@clisp.org>, 2002.
+
+   This program is free software; you can redistribute it and/or modify it
+   under the terms of the GNU Library 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library 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 "unistr.h"
+
+#if HAVE_STRDUP
+
+# include <string.h>
+
+uint8_t *
+u8_strdup (const uint8_t *s)
+{
+  return (uint8_t *) strdup ((const char *) s);
+}
+
+#else
+
+# define FUNC u8_strdup
+# define UNIT uint8_t
+# define U_STRLEN u8_strlen
+# include "u-strdup.h"
+
+#endif

new file mode 100644
--- /dev/null
+++ b/modules/unistr/u16-strdup
@@ -0,0 +1,25 @@
+Description:
+Copy UTF-16 string.
+
+Files:
+lib/unistr/u16-strdup.c
+lib/unistr/u-strdup.h
+
+Depends-on:
+unistr/base
+unistr/u16-strlen
+
+configure.ac:
+
+Makefile.am:
+lib_SOURCES += unistr/u16-strdup.c
+
+Include:
+"unistr.h"
+
+License:
+LGPL
+
+Maintainer:
+Bruno Haible
+

new file mode 100644
--- /dev/null
+++ b/modules/unistr/u32-strdup
@@ -0,0 +1,25 @@
+Description:
+Copy UTF-32 string.
+
+Files:
+lib/unistr/u32-strdup.c
+lib/unistr/u-strdup.h
+
+Depends-on:
+unistr/base
+unistr/u32-strlen
+
+configure.ac:
+
+Makefile.am:
+lib_SOURCES += unistr/u32-strdup.c
+
+Include:
+"unistr.h"
+
+License:
+LGPL
+
+Maintainer:
+Bruno Haible
+

new file mode 100644
--- /dev/null
+++ b/modules/unistr/u8-strdup
@@ -0,0 +1,26 @@
+Description:
+Copy UTF-8 string.
+
+Files:
+lib/unistr/u8-strdup.c
+lib/unistr/u-strdup.h
+
+Depends-on:
+unistr/base
+unistr/u8-strlen
+
+configure.ac:
+AC_CHECK_FUNCS_ONCE([strdup])
+
+Makefile.am:
+lib_SOURCES += unistr/u8-strdup.c
+
+Include:
+"unistr.h"
+
+License:
+LGPL
+
+Maintainer:
+Bruno Haible
+