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/*
* hash.c - Bob Jenkin's one-at-a-time hash
*
* Copyright (c) Chris Putnam 2020-2021
*
* Source code released under the GPL version 2
*/
#include <stdlib.h>
#include <string.h>
#include "hash.h"
/*
* Bob Jenkin's one-at-a-time hash
*/
static unsigned int
one_at_a_time_hash( const char *key, const unsigned int len, unsigned int HASH_SIZE )
{
unsigned int hash = 0, i;
for ( i=0; i<len; ++i ) {
hash += key[i];
hash += ( hash << 10 );
hash ^= ( hash >> 6 );
}
hash += ( hash << 3 );
hash ^= ( hash >> 11 );
hash += ( hash << 15 );
return hash % ( HASH_SIZE - 1 );
}
unsigned int
calculate_hash_char( const char *key, unsigned int HASH_SIZE )
{
return one_at_a_time_hash( key, strlen( key ), HASH_SIZE );
}
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