1269162Sbapt/* $OpenBSD: src/lib/libutil/ohash.h,v 1.2 2014/06/02 18:52:03 deraadt Exp $ */ 2228063Sbapt 3228063Sbapt/* Copyright (c) 1999, 2004 Marc Espie <espie@openbsd.org> 4228063Sbapt * 5228063Sbapt * Permission to use, copy, modify, and distribute this software for any 6228063Sbapt * purpose with or without fee is hereby granted, provided that the above 7228063Sbapt * copyright notice and this permission notice appear in all copies. 8228063Sbapt * 9228063Sbapt * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10228063Sbapt * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11228063Sbapt * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12228063Sbapt * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13228063Sbapt * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14228063Sbapt * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15228063Sbapt * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16228063Sbapt * 17228063Sbapt * $FreeBSD: releng/11.0/lib/libopenbsd/ohash.h 288629 2015-10-03 20:06:50Z bdrewery $ 18228063Sbapt */ 19228063Sbapt 20269162Sbapt#ifndef OHASH_H 21269162Sbapt#define OHASH_H 22269162Sbapt 23288629Sbdrewery#include <stddef.h> 24288629Sbdrewery 25228063Sbapt/* Open hashing support. 26228063Sbapt * Open hashing was chosen because it is much lighter than other hash 27228063Sbapt * techniques, and more efficient in most cases. 28228063Sbapt */ 29228063Sbapt 30269162Sbapt/* user-visible data structure */ 31228063Sbaptstruct ohash_info { 32228063Sbapt ptrdiff_t key_offset; 33228063Sbapt void *data; /* user data */ 34269162Sbapt void *(*calloc)(size_t, size_t, void *); 35269162Sbapt void (*free)(void *, void *); 36228063Sbapt void *(*alloc)(size_t, void *); 37228063Sbapt}; 38228063Sbapt 39228063Sbaptstruct _ohash_record; 40228063Sbapt 41269162Sbapt/* private structure. It's there just so you can do a sizeof */ 42228063Sbaptstruct ohash { 43228063Sbapt struct _ohash_record *t; 44228063Sbapt struct ohash_info info; 45228063Sbapt unsigned int size; 46228063Sbapt unsigned int total; 47228063Sbapt unsigned int deleted; 48228063Sbapt}; 49228063Sbapt 50228063Sbapt/* For this to be tweakable, we use small primitives, and leave part of the 51228063Sbapt * logic to the client application. e.g., hashing is left to the client 52228063Sbapt * application. We also provide a simple table entry lookup that yields 53228063Sbapt * a hashing table index (opaque) to be used in find/insert/remove. 54228063Sbapt * The keys are stored at a known position in the client data. 55228063Sbapt */ 56228063Sbapt__BEGIN_DECLS 57228063Sbaptvoid ohash_init(struct ohash *, unsigned, struct ohash_info *); 58228063Sbaptvoid ohash_delete(struct ohash *); 59228063Sbapt 60228063Sbaptunsigned int ohash_lookup_interval(struct ohash *, const char *, 61269162Sbapt const char *, uint32_t); 62228063Sbaptunsigned int ohash_lookup_memory(struct ohash *, const char *, 63269231Sbapt size_t, uint32_t); 64228063Sbaptvoid *ohash_find(struct ohash *, unsigned int); 65228063Sbaptvoid *ohash_remove(struct ohash *, unsigned int); 66228063Sbaptvoid *ohash_insert(struct ohash *, unsigned int, void *); 67228063Sbaptvoid *ohash_first(struct ohash *, unsigned int *); 68228063Sbaptvoid *ohash_next(struct ohash *, unsigned int *); 69228063Sbaptunsigned int ohash_entries(struct ohash *); 70228063Sbapt 71228063Sbaptvoid *ohash_create_entry(struct ohash_info *, const char *, const char **); 72269162Sbaptuint32_t ohash_interval(const char *, const char **); 73228063Sbapt 74228063Sbaptunsigned int ohash_qlookupi(struct ohash *, const char *, const char **); 75228063Sbaptunsigned int ohash_qlookup(struct ohash *, const char *); 76228063Sbapt__END_DECLS 77228063Sbapt#endif 78