echo shar: extracting "'hash.c'" '(2203 characters)'
sed 's/^X//' << \SHAR_EOF > 'hash.c'
X/* Copyright (c) 1986, Greg McGary */
Xstatic char sccsid[] = "@(#)hash.c	1.1 86/10/09";
X
Xchar *hashSearch();
Xint h1str();
Xint h2str();
X
X/*
X	Look for `key' in the hash table starting at address `base'.
X	`base' is a table containing `nel' elements of size `width'.
X	The hashing strategy we use is open addressing.  Apply the
X	primary hash function `h1' and the secondary hash function
X	`h2' when searching for `key' or an empty slot.  `compar'
X	is the comparison function that should be used to compare
X	the key with an element of the table.  It is called with two
X	arguments.  The first argument is the address of the key, and
X	the second argument is the address of the hash table element
X	in question.  `compar' should return 0 if the key matches the
X	element or the empty slot, and non-zero otherwise.
X
X	If a pointer to a long is provided for `probes' we will keep
X	a running total of open addressing hash probes.
X*/
Xchar *
XhashSearch(key, base, nel, width, h1, h2, compar, probes)
X	char		*key;		/* key to locate */
X	char		*base;		/* base of hash table */
X	register int	nel;		/* number of elements in table */
X	int		width;		/* width of each element */
X	int		(*h1)();	/* primary hash function */
X	int		(*h2)();	/* secondary hash function */
X	int		(*compar)();	/* key comparison function */
X	long		*probes;
X{
X	register int	hash1;
X	register int	hash2;
X	register char	*slot;
X
X	hash1 = (*h1)(key) % nel;
X	slot = &base[hash1 * width];
X
X	if (probes)
X		(*probes)++;
X	if ((*compar)(key, slot) == 0)
X		return slot;
X
X	hash2 = (*h2)(key);
X	for (;;) {
X		hash1 = (hash1 + hash2) % nel;
X		slot = &base[hash1 * width];
X
X		if (probes)
X			(*probes)++;
X		if ((*compar)(key, slot) == 0)
X			return slot;
X	}
X}
X
X#define	ABS(n)		((n) < 0 ? -(n) : (n))
X
X/*
X	A Primary hash function for string keys.
X*/
Xint
Xh1str(key)
X	register char	*key;
X{
X	register int	sum;
X	register int	s;
X
X	for (sum = s = 0; *key; s++)
X		sum += ((*key++) << s);
X
X	return ABS(sum);
X}
X
X/*
X	A Secondary hash function for string keys.
X*/
Xint
Xh2str(key)
X	register char	*key;
X{
X	register int	sum;
X	register int	s;
X	char		*keysav;
X
X	keysav = key;
X	key = &key[strlen(key)];
X
X	for (sum = s = 0; key > keysav; s++)
X		sum += ((*--key) << s);
X
X	return ABS(sum) | 1;
X}
SHAR_EOF
if test 2203 -ne "`wc -c < 'hash.c'`"
then
	echo shar: error transmitting "'hash.c'" '(should have been 2203 characters)'
fi