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-rw-r--r--locale/strlen-hash.h51
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diff --git a/locale/strlen-hash.h b/locale/strlen-hash.h
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+/* strlen-hash - Implements hashing function for string with known length.
+Copyright (C) 1996 Free Software Foundation, Inc.
+Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
+
+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 <sys/types.h>
+
+/* We assume to have `size_t' value with at least 32 bits. */
+#define HASHWORDBITS 32
+
+
+/* Defines the so called `hashpjw' function by P.J. Weinberger
+ [see Aho/Sethi/Ullman, COMPILERS: Principles, Techniques and Tools,
+ 1986, 1987 Bell Telephone Laboratories, Inc.] */
+static size_t hash_string (const char *__str_param, size_t __len);
+
+static inline size_t
+hash_string (const char *str_param, size_t len)
+{
+ size_t hval, g;
+ const char *end_str = str_param + len;
+
+ /* Compute the hash value for the given string. */
+ hval = len;
+ while (str_param != end_str)
+ {
+ hval <<= 4;
+ hval += (size_t) *str_param++;
+ g = hval & ((size_t) 0xf << (HASHWORDBITS - 4));
+ if (g != 0)
+ {
+ hval ^= g >> (HASHWORDBITS - 8);
+ hval ^= g;
+ }
+ }
+ return hval;
+}