new file mode 100644
--- /dev/null
+++ b/lib/strtouxmax.c
@@ -0,0 +1,104 @@
+/* Convert string representation of a number into an uintmax_t value.
+   Copyright 2001 Free Software Foundation, Inc.
+
+   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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+
+/* Written by Paul Eggert. */
+
+#if HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#if HAVE_INTTYPES_H
+# include <inttypes.h>
+#endif
+
+#if HAVE_STDLIB_H
+# include <stdlib.h>
+#endif
+
+#ifndef PARAMS
+# if defined PROTOTYPES || defined __STDC__
+#  define PARAMS(Args) Args
+# else
+#  define PARAMS(Args) ()
+# endif
+#endif
+
+#ifdef STRTOUXMAX_UNSIGNED
+# ifndef HAVE_DECL_STRTOUL
+"this configure-time declaration test was not run"
+# endif
+# if !HAVE_DECL_STRTOUL
+unsigned long strtoul PARAMS ((char const *, char **, int));
+# endif
+# ifndef HAVE_DECL_STRTOULL
+"this configure-time declaration test was not run"
+# endif
+# if !HAVE_DECL_STRTOULL && HAVE_UNSIGNED_LONG_LONG
+unsigned long long strtoull PARAMS ((char const *, char **, int));
+# endif
+
+#else
+
+# ifndef HAVE_DECL_STRTOL
+"this configure-time declaration test was not run"
+# endif
+# if !HAVE_DECL_STRTOL
+long strtol PARAMS ((char const *, char **, int));
+# endif
+# ifndef HAVE_DECL_STRTOLL
+"this configure-time declaration test was not run"
+# endif
+# if !HAVE_DECL_STRTOLL && HAVE_UNSIGNED_LONG_LONG
+long long strtoll PARAMS ((char const *, char **, int));
+# endif
+#endif
+
+#ifndef STRTOUXMAX_UNSIGNED
+# define strtoumax strtoimax
+# define uintmax_t intmax_t
+# define strtoull strtoll
+# define strtoul strtol
+#endif
+
+uintmax_t
+strtoumax (char const *ptr, char **endptr, int base)
+{
+#define USE_IF_EQUIVALENT(function) \
+    if (sizeof (uintmax_t) == sizeof function (ptr, endptr, base)) \
+      return function (ptr, endptr, base);
+
+#if HAVE_UNSIGNED_LONG_LONG
+    USE_IF_EQUIVALENT (strtoull)
+#endif
+
+  USE_IF_EQUIVALENT (strtoul)
+
+  abort ();
+}
+
+#ifdef TESTING
+# include <stdio.h>
+int
+main ()
+{
+  char *p, *endptr;
+  printf ("sizeof xintmax_t: %d\n", sizeof (uintmax_t));
+  printf ("sizeof strtoxll(): %d\n", sizeof strtoull(p, &endptr, 10));
+  printf ("sizeof strtoxl(): %d\n", sizeof strtoul(p, &endptr, 10));
+  exit (0);
+}
+#endif