1 files changed, 50 insertions, 0 deletions
diff --git a/lib/wcwidth.c b/lib/wcwidth.c
new file mode 100644
index 0000000..b94fad0
--- /dev/null
+++ b/lib/wcwidth.c
@@ -0,0 +1,50 @@
+/* Determine the number of screen columns needed for a character.
+   Copyright (C) 2006-2007, 2010-2016 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 3 of the License, 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, see <http://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+/* Specification.  */
+#include <wchar.h>
+
+/* Get iswprint.  */
+#include <wctype.h>
+
+#include "localcharset.h"
+#include "streq.h"
+#include "uniwidth.h"
+
+int
+wcwidth (wchar_t wc)
+#undef wcwidth
+{
+  /* In UTF-8 locales, use a Unicode aware width function.  */
+  const char *encoding = locale_charset ();
+  if (STREQ_OPT (encoding, "UTF-8", 'U', 'T', 'F', '-', '8', 0, 0, 0 ,0))
+    {
+      /* We assume that in a UTF-8 locale, a wide character is the same as a
+         Unicode character.  */
+      return uc_width (wc, encoding);
+    }
+  else
+    {
+      /* Otherwise, fall back to the system's wcwidth function.  */
+#if HAVE_WCWIDTH
+      return wcwidth (wc);
+#else
+      return wc == 0 ? 0 : iswprint (wc) ? 1 : -1;
+#endif
+    }
+}