1*4afad3d8SPeter Avalos /* $OpenBSD: ohash_lookup_memory.c,v 1.3 2006/01/16 15:52:25 espie Exp $ */
2*4afad3d8SPeter Avalos /* ex:ts=8 sw=4:
3*4afad3d8SPeter Avalos */
4*4afad3d8SPeter Avalos
5*4afad3d8SPeter Avalos /* Copyright (c) 1999, 2004 Marc Espie <espie@openbsd.org>
6*4afad3d8SPeter Avalos *
7*4afad3d8SPeter Avalos * Permission to use, copy, modify, and distribute this software for any
8*4afad3d8SPeter Avalos * purpose with or without fee is hereby granted, provided that the above
9*4afad3d8SPeter Avalos * copyright notice and this permission notice appear in all copies.
10*4afad3d8SPeter Avalos *
11*4afad3d8SPeter Avalos * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12*4afad3d8SPeter Avalos * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13*4afad3d8SPeter Avalos * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14*4afad3d8SPeter Avalos * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15*4afad3d8SPeter Avalos * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16*4afad3d8SPeter Avalos * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17*4afad3d8SPeter Avalos * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18*4afad3d8SPeter Avalos *
19*4afad3d8SPeter Avalos * $FreeBSD: src/usr.bin/m4/lib/ohash_lookup_memory.c,v 1.2 2012/11/17 01:54:24 svnexp Exp $
20*4afad3d8SPeter Avalos */
21*4afad3d8SPeter Avalos
22*4afad3d8SPeter Avalos #include "ohash_int.h"
23*4afad3d8SPeter Avalos
24*4afad3d8SPeter Avalos unsigned int
ohash_lookup_memory(struct ohash * h,const char * k,size_t size,uint32_t hv)25*4afad3d8SPeter Avalos ohash_lookup_memory(struct ohash *h, const char *k, size_t size, uint32_t hv)
26*4afad3d8SPeter Avalos {
27*4afad3d8SPeter Avalos unsigned int i, incr;
28*4afad3d8SPeter Avalos unsigned int empty;
29*4afad3d8SPeter Avalos
30*4afad3d8SPeter Avalos #ifdef STATS_HASH
31*4afad3d8SPeter Avalos STAT_HASH_LOOKUP++;
32*4afad3d8SPeter Avalos #endif
33*4afad3d8SPeter Avalos empty = NONE;
34*4afad3d8SPeter Avalos i = hv % h->size;
35*4afad3d8SPeter Avalos incr = ((hv % (h->size-2)) & ~1) + 1;
36*4afad3d8SPeter Avalos while (h->t[i].p != NULL) {
37*4afad3d8SPeter Avalos #ifdef STATS_HASH
38*4afad3d8SPeter Avalos STAT_HASH_LENGTH++;
39*4afad3d8SPeter Avalos #endif
40*4afad3d8SPeter Avalos if (h->t[i].p == DELETED) {
41*4afad3d8SPeter Avalos if (empty == NONE)
42*4afad3d8SPeter Avalos empty = i;
43*4afad3d8SPeter Avalos } else if (h->t[i].hv == hv &&
44*4afad3d8SPeter Avalos memcmp(h->t[i].p+h->info.key_offset, k, size) == 0) {
45*4afad3d8SPeter Avalos if (empty != NONE) {
46*4afad3d8SPeter Avalos h->t[empty].hv = hv;
47*4afad3d8SPeter Avalos h->t[empty].p = h->t[i].p;
48*4afad3d8SPeter Avalos h->t[i].p = DELETED;
49*4afad3d8SPeter Avalos return empty;
50*4afad3d8SPeter Avalos } else {
51*4afad3d8SPeter Avalos #ifdef STATS_HASH
52*4afad3d8SPeter Avalos STAT_HASH_POSITIVE++;
53*4afad3d8SPeter Avalos #endif
54*4afad3d8SPeter Avalos }
55*4afad3d8SPeter Avalos return i;
56*4afad3d8SPeter Avalos }
57*4afad3d8SPeter Avalos i += incr;
58*4afad3d8SPeter Avalos if (i >= h->size)
59*4afad3d8SPeter Avalos i -= h->size;
60*4afad3d8SPeter Avalos }
61*4afad3d8SPeter Avalos
62*4afad3d8SPeter Avalos /* Found an empty position. */
63*4afad3d8SPeter Avalos if (empty != NONE)
64*4afad3d8SPeter Avalos i = empty;
65*4afad3d8SPeter Avalos h->t[i].hv = hv;
66*4afad3d8SPeter Avalos return i;
67*4afad3d8SPeter Avalos }
68