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-rw-r--r--intl/hash-string.c47
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diff --git a/intl/hash-string.c b/intl/hash-string.c
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+/* Implements a string hashing function.
+ Copyright (C) 1995, 1997, 1998, 2000, 2003 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ 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. */
+
+#include "hash-string.h"
+
+
+/* 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.] */
+unsigned long int
+__hash_string (str_param)
+ const char *str_param;
+{
+ unsigned long int hval, g;
+ const char *str = str_param;
+
+ /* Compute the hash value for the given string. */
+ hval = 0;
+ while (*str != '\0')
+ {
+ hval <<= 4;
+ hval += (unsigned long int) *str++;
+ g = hval & ((unsigned long int) 0xf << (HASHWORDBITS - 4));
+ if (g != 0)
+ {
+ hval ^= g >> (HASHWORDBITS - 8);
+ hval ^= g;
+ }
+ }
+ return hval;
+}