Really add wcwidth.h.

lib/wcwidth.h

@@ -0,0 +1,70 @@
+/* Determine the number of screen columns needed for a character.
+   Copyright (C) 2006 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
+
+#ifndef _gl_WCWIDTH_H
+#define _gl_WCWIDTH_H
+
+#if HAVE_WCHAR_T
+
+/* Get wcwidth if available, along with wchar_t.  */
+# if HAVE_WCHAR_H
+/* Tru64 with Desktop Toolkit C has a bug: <stdio.h> must be included before
+   <wchar.h>.
+   BSD/OS 4.1 has a bug: <stdio.h> and <time.h> must be included before
+   <wchar.h>.  */
+#  include <stdio.h>
+#  include <time.h>
+#  include <wchar.h>
+# endif
+
+/* Get iswprint.  */
+# if HAVE_WCTYPE_H
+#  include <wctype.h>
+# endif
+# if !defined iswprint && !HAVE_ISWPRINT
+#  define iswprint(wc) 1
+# endif
+
+# ifndef HAVE_DECL_WCWIDTH
+"this configure-time declaration test was not run"
+# endif
+# ifndef wcwidth
+#  if !HAVE_WCWIDTH
+
+/* wcwidth doesn't exist, so assume all printable characters have
+   width 1.  */
+static inline int
+wcwidth (wchar_t wc)
+{
+  return wc == 0 ? 0 : iswprint (wc) ? 1 : -1;
+}
+
+#  elif !HAVE_DECL_WCWIDTH
+
+/* wcwidth exists but is not declared.  */
+extern
+#   ifdef __cplusplus
+"C"
+#   endif
+int wcwidth (int /* actually wchar_t */);
+
+#  endif
+# endif
+
+#endif /* HAVE_WCHAR_H */
+
+#endif /* _gl_WCWIDTH_H */