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-rw-r--r--wctype/cname-lookup.h45
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diff --git a/wctype/cname-lookup.h b/wctype/cname-lookup.h
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+/* Copyright (C) 1996 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+Contributed by Ulrich Drepper, <drepper@gnu.ai.mit.edu>.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA.  */
+
+#include "localeinfo.h"
+
+/* Some words on the runtime of this functions.  Although there is a
+   loop in the function the runtime is asymptotically quasi constant.
+   The reason is that even for the largest character sets HASH_LAYERS
+   will not grow beyond 15 (a guess!).  */
+static __inline size_t
+cname_lookup (wint_t wc)
+{
+  extern unsigned int *__ctype_names;
+  unsigned int hash_size, hash_layers;
+  size_t result, cnt;
+
+  hash_size = _NL_CURRENT_WORD (LC_CTYPE, _NL_CTYPE_HASH_SIZE);
+  hash_layers = _NL_CURRENT_WORD (LC_CTYPE, _NL_CTYPE_HASH_LAYERS);
+
+  result = wc % hash_size;
+  for (cnt = 0; cnt < hash_layers; ++cnt)
+    {
+      if (__ctype_names[result] == wc)
+	break;
+      result += hash_size;
+    }
+
+  return cnt < hash_layers ? result : ~((size_t) 0);
+}