1 files changed, 43 insertions, 0 deletions
diff --git a/lib/wcswidth-impl.h b/lib/wcswidth-impl.h
new file mode 100644
index 0000000..e023f24
--- /dev/null
+++ b/lib/wcswidth-impl.h
@@ -0,0 +1,43 @@
+/* Determine number of screen columns needed for a size-bounded wide string.
+   Copyright (C) 1999, 2011-2016 Free Software Foundation, Inc.
+   Written by Bruno Haible <bruno@clisp.org>, 1999.
+
+   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/>.  */
+
+int
+wcswidth (const wchar_t *s, size_t n)
+{
+  int count = 0;
+  for (; n > 0; s++, n--)
+    {
+      wchar_t c = *s;
+      if (c == (wchar_t)'\0')
+        break;
+      {
+        int width = wcwidth (c);
+        if (width < 0)
+          goto found_nonprinting;
+        if (width > INT_MAX - count)
+          goto overflow;
+        count += width;
+      }
+    }
+  return count;
+
+ found_nonprinting:
+  return -1;
+
+ overflow:
+  return INT_MAX;
+}