Import xz 5.2.2 (as of svn r86089)

m4/tuklib_mbstr.m4

@@ -0,0 +1,30 @@
+#
+# SYNOPSIS
+#
+#   TUKLIB_MBSTR
+#
+# DESCRIPTION
+#
+#   Check if multibyte and wide character functionality is available
+#   for use by tuklib_mbstr_* functions. If not enough multibyte string
+#   support is available in the C library, the functions keep working
+#   with the assumption that all strings are a in single-byte character
+#   set without combining characters, e.g. US-ASCII or ISO-8859-*.
+#
+#   This .m4 file and tuklib_mbstr.h are common to all tuklib_mbstr_*
+#   functions, but each function is put into a separate .c file so
+#   that it is possible to pick only what is strictly needed.
+#
+# COPYING
+#
+#   Author: Lasse Collin
+#
+#   This file has been put into the public domain.
+#   You can do whatever you want with this file.
+#
+
+AC_DEFUN_ONCE([TUKLIB_MBSTR], [
+AC_REQUIRE([TUKLIB_COMMON])
+AC_FUNC_MBRTOWC
+AC_CHECK_FUNCS([wcwidth])
+])dnl