1228063Sbapt/* $OpenBSD: ohash_lookup_memory.c,v 1.3 2006/01/16 15:52:25 espie Exp $ */ 2228063Sbapt/* ex:ts=8 sw=4: 3228063Sbapt */ 4228063Sbapt 5228063Sbapt/* Copyright (c) 1999, 2004 Marc Espie <espie@openbsd.org> 6228063Sbapt * 7228063Sbapt * Permission to use, copy, modify, and distribute this software for any 8228063Sbapt * purpose with or without fee is hereby granted, provided that the above 9228063Sbapt * copyright notice and this permission notice appear in all copies. 10228063Sbapt * 11228063Sbapt * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 12228063Sbapt * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 13228063Sbapt * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 14228063Sbapt * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 15228063Sbapt * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 16228063Sbapt * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 17228063Sbapt * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18228063Sbapt */ 19228063Sbapt#include <sys/cdefs.h> 20228063Sbapt__FBSDID("$FreeBSD$"); 21228063Sbapt 22228063Sbapt#include "ohash_int.h" 23228063Sbapt 24228063Sbaptunsigned int 25228063Sbaptohash_lookup_memory(struct ohash *h, const char *k, size_t size, uint32_t hv) 26228063Sbapt{ 27228063Sbapt unsigned int i, incr; 28228063Sbapt unsigned int empty; 29228063Sbapt 30228063Sbapt#ifdef STATS_HASH 31228063Sbapt STAT_HASH_LOOKUP++; 32228063Sbapt#endif 33228063Sbapt empty = NONE; 34228063Sbapt i = hv % h->size; 35228063Sbapt incr = ((hv % (h->size-2)) & ~1) + 1; 36228063Sbapt while (h->t[i].p != NULL) { 37228063Sbapt#ifdef STATS_HASH 38228063Sbapt STAT_HASH_LENGTH++; 39228063Sbapt#endif 40228063Sbapt if (h->t[i].p == DELETED) { 41228063Sbapt if (empty == NONE) 42228063Sbapt empty = i; 43228063Sbapt } else if (h->t[i].hv == hv && 44228063Sbapt memcmp(h->t[i].p+h->info.key_offset, k, size) == 0) { 45228063Sbapt if (empty != NONE) { 46228063Sbapt h->t[empty].hv = hv; 47228063Sbapt h->t[empty].p = h->t[i].p; 48228063Sbapt h->t[i].p = DELETED; 49228063Sbapt return empty; 50228063Sbapt } else { 51228063Sbapt#ifdef STATS_HASH 52228063Sbapt STAT_HASH_POSITIVE++; 53228063Sbapt#endif 54228063Sbapt } return i; 55228063Sbapt } 56228063Sbapt i += incr; 57228063Sbapt if (i >= h->size) 58228063Sbapt i -= h->size; 59228063Sbapt } 60228063Sbapt 61228063Sbapt /* Found an empty position. */ 62228063Sbapt if (empty != NONE) 63228063Sbapt i = empty; 64228063Sbapt h->t[i].hv = hv; 65228063Sbapt return i; 66228063Sbapt} 67