[unix-history] / usr / src / usr.bin / lint / hash.c

#ifndef lint
static char sccsid[] = "@(#)hash.c	1.1	(Berkeley)	3/29/83";
#endif lint

/*
 * Hash function.  Used for pass 2 symbol table and string table,
 * and structure/union name passing between passes.
 * The hash function is a modular hash of
 * the sum of the characters with the sum
 * rotated before each successive character
 * is added.
 * Only 15 bits are used.
 */
#ifdef FLEXNAMES
hashstr(s)
#else
hashstr(s, n)
register n;
#endif
register char *s;
{
	register i;

	i = 0;
#ifdef FLEXNAMES
	while (*s)
#else
	while (n-- > 0 && *s)
#endif
		i = (i << 3 | i >> 12 & 0x07) + *s++;
	return i & 0x7fff;
}
Commit	Line	Data
49531380	1	#ifndef lint
0f4556f1	2	static char sccsid[] = "@(#)hash.c 1.1 (Berkeley) 3/29/83";
49531380 EW	3	#endif lint
	4
	5	/*
	6	* Hash function. Used for pass 2 symbol table and string table,
	7	* and structure/union name passing between passes.
	8	* The hash function is a modular hash of
	9	* the sum of the characters with the sum
	10	* rotated before each successive character
	11	* is added.
	12	* Only 15 bits are used.
	13	*/
	14	#ifdef FLEXNAMES
	15	hashstr(s)
	16	#else
	17	hashstr(s, n)
	18	register n;
	19	#endif
	20	register char *s;
	21	{
	22	register i;
	23
	24	i = 0;
	25	#ifdef FLEXNAMES
	26	while (*s)
	27	#else
	28	while (n-- > 0 && *s)
	29	#endif
	30	i = (i << 3 \| i >> 12 & 0x07) + *s++;
	31	return i & 0x7fff;
	32	}