1*61d06d6bSBaptiste Daroussin /* $OpenBSD: ohash.h,v 1.2 2014/06/02 18:52:03 deraadt Exp $ */ 2*61d06d6bSBaptiste Daroussin 3*61d06d6bSBaptiste Daroussin /* Copyright (c) 1999, 2004 Marc Espie <espie@openbsd.org> 4*61d06d6bSBaptiste Daroussin * 5*61d06d6bSBaptiste Daroussin * Permission to use, copy, modify, and distribute this software for any 6*61d06d6bSBaptiste Daroussin * purpose with or without fee is hereby granted, provided that the above 7*61d06d6bSBaptiste Daroussin * copyright notice and this permission notice appear in all copies. 8*61d06d6bSBaptiste Daroussin * 9*61d06d6bSBaptiste Daroussin * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10*61d06d6bSBaptiste Daroussin * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11*61d06d6bSBaptiste Daroussin * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12*61d06d6bSBaptiste Daroussin * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13*61d06d6bSBaptiste Daroussin * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14*61d06d6bSBaptiste Daroussin * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15*61d06d6bSBaptiste Daroussin * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16*61d06d6bSBaptiste Daroussin */ 17*61d06d6bSBaptiste Daroussin 18*61d06d6bSBaptiste Daroussin #ifndef OHASH_H 19*61d06d6bSBaptiste Daroussin #define OHASH_H 20*61d06d6bSBaptiste Daroussin 21*61d06d6bSBaptiste Daroussin /* Open hashing support. 22*61d06d6bSBaptiste Daroussin * Open hashing was chosen because it is much lighter than other hash 23*61d06d6bSBaptiste Daroussin * techniques, and more efficient in most cases. 24*61d06d6bSBaptiste Daroussin */ 25*61d06d6bSBaptiste Daroussin 26*61d06d6bSBaptiste Daroussin /* user-visible data structure */ 27*61d06d6bSBaptiste Daroussin struct ohash_info { 28*61d06d6bSBaptiste Daroussin ptrdiff_t key_offset; 29*61d06d6bSBaptiste Daroussin void *data; /* user data */ 30*61d06d6bSBaptiste Daroussin void *(*calloc)(size_t, size_t, void *); 31*61d06d6bSBaptiste Daroussin void (*free)(void *, void *); 32*61d06d6bSBaptiste Daroussin void *(*alloc)(size_t, void *); 33*61d06d6bSBaptiste Daroussin }; 34*61d06d6bSBaptiste Daroussin 35*61d06d6bSBaptiste Daroussin struct _ohash_record; 36*61d06d6bSBaptiste Daroussin 37*61d06d6bSBaptiste Daroussin /* private structure. It's there just so you can do a sizeof */ 38*61d06d6bSBaptiste Daroussin struct ohash { 39*61d06d6bSBaptiste Daroussin struct _ohash_record *t; 40*61d06d6bSBaptiste Daroussin struct ohash_info info; 41*61d06d6bSBaptiste Daroussin unsigned int size; 42*61d06d6bSBaptiste Daroussin unsigned int total; 43*61d06d6bSBaptiste Daroussin unsigned int deleted; 44*61d06d6bSBaptiste Daroussin }; 45*61d06d6bSBaptiste Daroussin 46*61d06d6bSBaptiste Daroussin /* For this to be tweakable, we use small primitives, and leave part of the 47*61d06d6bSBaptiste Daroussin * logic to the client application. e.g., hashing is left to the client 48*61d06d6bSBaptiste Daroussin * application. We also provide a simple table entry lookup that yields 49*61d06d6bSBaptiste Daroussin * a hashing table index (opaque) to be used in find/insert/remove. 50*61d06d6bSBaptiste Daroussin * The keys are stored at a known position in the client data. 51*61d06d6bSBaptiste Daroussin */ 52*61d06d6bSBaptiste Daroussin void ohash_init(struct ohash *, unsigned, struct ohash_info *); 53*61d06d6bSBaptiste Daroussin void ohash_delete(struct ohash *); 54*61d06d6bSBaptiste Daroussin 55*61d06d6bSBaptiste Daroussin unsigned int ohash_lookup_interval(struct ohash *, const char *, 56*61d06d6bSBaptiste Daroussin const char *, uint32_t); 57*61d06d6bSBaptiste Daroussin unsigned int ohash_lookup_memory(struct ohash *, const char *, 58*61d06d6bSBaptiste Daroussin size_t, uint32_t); 59*61d06d6bSBaptiste Daroussin void *ohash_find(struct ohash *, unsigned int); 60*61d06d6bSBaptiste Daroussin void *ohash_remove(struct ohash *, unsigned int); 61*61d06d6bSBaptiste Daroussin void *ohash_insert(struct ohash *, unsigned int, void *); 62*61d06d6bSBaptiste Daroussin void *ohash_first(struct ohash *, unsigned int *); 63*61d06d6bSBaptiste Daroussin void *ohash_next(struct ohash *, unsigned int *); 64*61d06d6bSBaptiste Daroussin unsigned int ohash_entries(struct ohash *); 65*61d06d6bSBaptiste Daroussin 66*61d06d6bSBaptiste Daroussin void *ohash_create_entry(struct ohash_info *, const char *, const char **); 67*61d06d6bSBaptiste Daroussin uint32_t ohash_interval(const char *, const char **); 68*61d06d6bSBaptiste Daroussin 69*61d06d6bSBaptiste Daroussin unsigned int ohash_qlookupi(struct ohash *, const char *, const char **); 70*61d06d6bSBaptiste Daroussin unsigned int ohash_qlookup(struct ohash *, const char *); 71*61d06d6bSBaptiste Daroussin 72*61d06d6bSBaptiste Daroussin #endif 73