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/* Copyright (C) 1989, 1990, 1991, 1992, 2006, 2009
Free Software Foundation, Inc.
Written by James Clark (jjc@jclark.com)
This file is part of groff.
groff 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 3 of the License, or
(at your option) any later version.
groff 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, see <http://www.gnu.org/licenses/>. */
#include "ptable.h"
#include "errarg.h"
#include "error.h"
unsigned long hash_string(const char *s)
{
// This is the mythical Aho-Hopcroft-Ullman hash function.
// TODO: Improve. See http://www.haible.de/bruno/hashfunc.html
assert(s != 0);
unsigned long h = 0, g;
while (*s != 0) {
h <<= 4;
h += *s++;
if ((g = h & 0xf0000000) != 0) {
h ^= g >> 24;
h ^= g;
}
}
return h;
}
static const unsigned table_sizes[] = {
101, 503, 1009, 2003, 3001, 4001, 5003, 10007, 20011, 40009,
80021, 160001, 500009, 1000003, 2000003, 4000037, 8000009,
16000057, 32000011, 64000031, 128000003, 0
};
unsigned next_ptable_size(unsigned n)
{
const unsigned *p;
for (p = table_sizes; *p <= n; p++)
if (*p == 0)
fatal("cannot expand table");
return *p;
}
// end of ptable.cpp
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