2N/A * Copyright (c) 1990, 1993 2N/A * The Regents of the University of California. All rights reserved. 2N/A * This code is derived from software contributed to Berkeley by 2N/A * Redistribution and use in source and binary forms, with or without 2N/A * modification, are permitted provided that the following conditions 2N/A * 1. Redistributions of source code must retain the above copyright 2N/A * notice, this list of conditions and the following disclaimer. 2N/A * 2. Redistributions in binary form must reproduce the above copyright 2N/A * notice, this list of conditions and the following disclaimer in the 2N/A * documentation and/or other materials provided with the distribution. 2N/A * 3. All advertising materials mentioning features or use of this software 2N/A * must display the following acknowledgement: 2N/A * This product includes software developed by the University of 2N/A * California, Berkeley and its contributors. 2N/A * 4. Neither the name of the University nor the names of its contributors 2N/A * may be used to endorse or promote products derived from this software 2N/A * without specific prior written permission. 2N/A * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 2N/A * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 2N/A * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 2N/A * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 2N/A * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2N/A * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2N/A * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2N/A * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2N/A * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2N/A * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 2N/A#
endif /* LIBC_SCCS and not lint */ 2N/A/* Default hash function. */ 2N/A * Assume that we've already split the bucket to which this key hashes, 2N/A * calculate that bucket, and check that in fact we did already split it. 2N/A * EJB's original hsearch hash. 2N/A /* Convert string to integer */ 2N/A * Phong Vo's linear congruential hash 2N/A#
define dcharhash(h, c) ((h) =
0x63c63cd9*(h) +
0x9c39c33d + (c))
2N/A for (h = 0; k != e;) {
2N/A * This is INCREDIBLY ugly, but fast. We break the string up into 8 byte 2N/A * units. On the first time through the loop we get the "leftover bytes" 2N/A * (strlen % 8). On every other iteration, we perform 8 HASHC's so we handle 2N/A * all 8 bytes. Essentially, this saves us 7 cmp & branch instructions. If 2N/A * this routine is heavily used enough, it's worth the ugly coding. 2N/A * Ozan Yigit's original sdbm hash. 2N/A do {
/* All fall throughs */ 2N/A/* Chris Torek's hash function. */ 2N/A do {
/* All fall throughs */