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-rw-r--r--intl/hash-string.h56
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diff --git a/intl/hash-string.h b/intl/hash-string.h
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+/* hash-string - Implements a string hashing function.
+   Copyright (C) 1995 Software Foundation, Inc.
+
+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 2, 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, write to the Free Software
+Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+
+#ifdef HAVE_VALUES_H
+# include <values.h>
+#endif
+
+/* @@ end of prolog @@ */
+
+#ifndef BITSPERBYTE
+# define BITSPERBYTE 8
+#endif
+
+#ifndef LONGBITS
+# define LONGBITS (sizeof (long) * BITSPERBYTE)
+#endif	/* LONGBITS  */
+
+/* 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 inline unsigned long
+hash_string (str_param)
+     const char *str_param;
+{
+  unsigned long 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) *str++;
+      g = hval & ((unsigned long) 0xf << (LONGBITS - 4));
+      if (g != 0)
+	{
+	  hval ^= g >> (LONGBITS - 8);
+	  hval ^= g;
+	}
+    }
+  return hval;
+}