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-rw-r--r--locale/hashval.h41
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diff --git a/locale/hashval.h b/locale/hashval.h
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+/* Implement simple hashing table with string based keys.
+ Copyright (C) 1994-1997, 2000, 2001, 2002 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>, October 1994.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+unsigned long
+compute_hashval (key, keylen)
+ const void *key;
+ size_t keylen;
+{
+ size_t cnt;
+ unsigned long int hval;
+
+ /* Compute the hash value for the given string. The algorithm
+ is taken from [Aho,Sethi,Ullman], modified to reduce the number of
+ collisions for short strings with very varied bit patterns.
+ See http://www.clisp.org/haible/hashfunc.html. */
+ cnt = 0;
+ hval = keylen;
+ while (cnt < keylen)
+ {
+ hval = (hval << 9) | (hval >> (LONGBITS - 9));
+ hval += (unsigned long int) *(((char *) key) + cnt++);
+ }
+ return hval != 0 ? hval : ~((unsigned long) 0);
+}