1 /* $OpenBSD: ohash_interval.c,v 1.3 2006/01/16 15:52:25 espie Exp $ */ 2 /* ex:ts=8 sw=4: 3 */ 4 5 /* Copyright (c) 1999, 2004 Marc Espie <espie@openbsd.org> 6 * 7 * Permission to use, copy, modify, and distribute this software for any 8 * purpose with or without fee is hereby granted, provided that the above 9 * copyright notice and this permission notice appear in all copies. 10 * 11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18 */ 19 20 #include "ohash_int.h" 21 22 uint32_t 23 ohash_interval(const char *s, const char **e) 24 { 25 uint32_t k; 26 27 if (!*e) 28 *e = s + strlen(s); 29 if (s == *e) 30 k = 0; 31 else 32 k = *s++; 33 while (s != *e) 34 k = ((k << 2) | (k >> 30)) ^ *s++; 35 return k; 36 } 37