1*71dafaa1Schristos #ifndef OHASH_H 2*71dafaa1Schristos #define OHASH_H 3*71dafaa1Schristos /* $OpenBSD: ohash.h,v 1.8 2005/12/29 18:54:47 jaredy Exp $ */ 4*71dafaa1Schristos /* ex:ts=8 sw=4: 5*71dafaa1Schristos */ 6*71dafaa1Schristos 7*71dafaa1Schristos /* Copyright (c) 1999, 2004 Marc Espie <espie@openbsd.org> 8*71dafaa1Schristos * 9*71dafaa1Schristos * Permission to use, copy, modify, and distribute this software for any 10*71dafaa1Schristos * purpose with or without fee is hereby granted, provided that the above 11*71dafaa1Schristos * copyright notice and this permission notice appear in all copies. 12*71dafaa1Schristos * 13*71dafaa1Schristos * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 14*71dafaa1Schristos * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 15*71dafaa1Schristos * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 16*71dafaa1Schristos * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 17*71dafaa1Schristos * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 18*71dafaa1Schristos * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 19*71dafaa1Schristos * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 20*71dafaa1Schristos */ 21*71dafaa1Schristos 22*71dafaa1Schristos /* Open hashing support. 23*71dafaa1Schristos * Open hashing was chosen because it is much lighter than other hash 24*71dafaa1Schristos * techniques, and more efficient in most cases. 25*71dafaa1Schristos */ 26*71dafaa1Schristos 27*71dafaa1Schristos struct ohash_info { 28*71dafaa1Schristos ptrdiff_t key_offset; 29*71dafaa1Schristos void *data; /* user data */ 30*71dafaa1Schristos void *(*halloc)(size_t, void *); 31*71dafaa1Schristos void (*hfree)(void *, size_t, void *); 32*71dafaa1Schristos void *(*alloc)(size_t, void *); 33*71dafaa1Schristos }; 34*71dafaa1Schristos 35*71dafaa1Schristos struct _ohash_record; 36*71dafaa1Schristos 37*71dafaa1Schristos struct ohash { 38*71dafaa1Schristos struct _ohash_record *t; 39*71dafaa1Schristos struct ohash_info info; 40*71dafaa1Schristos unsigned int size; 41*71dafaa1Schristos unsigned int total; 42*71dafaa1Schristos unsigned int deleted; 43*71dafaa1Schristos }; 44*71dafaa1Schristos 45*71dafaa1Schristos /* For this to be tweakable, we use small primitives, and leave part of the 46*71dafaa1Schristos * logic to the client application. e.g., hashing is left to the client 47*71dafaa1Schristos * application. We also provide a simple table entry lookup that yields 48*71dafaa1Schristos * a hashing table index (opaque) to be used in find/insert/remove. 49*71dafaa1Schristos * The keys are stored at a known position in the client data. 50*71dafaa1Schristos */ 51*71dafaa1Schristos __BEGIN_DECLS 52*71dafaa1Schristos void ohash_init(struct ohash *, unsigned, struct ohash_info *); 53*71dafaa1Schristos void ohash_delete(struct ohash *); 54*71dafaa1Schristos 55*71dafaa1Schristos unsigned int ohash_lookup_interval(struct ohash *, const char *, 56*71dafaa1Schristos const char *, u_int32_t); 57*71dafaa1Schristos unsigned int ohash_lookup_memory(struct ohash *, const char *, 58*71dafaa1Schristos size_t, u_int32_t); 59*71dafaa1Schristos void *ohash_find(struct ohash *, unsigned int); 60*71dafaa1Schristos void *ohash_remove(struct ohash *, unsigned int); 61*71dafaa1Schristos void *ohash_insert(struct ohash *, unsigned int, void *); 62*71dafaa1Schristos void *ohash_first(struct ohash *, unsigned int *); 63*71dafaa1Schristos void *ohash_next(struct ohash *, unsigned int *); 64*71dafaa1Schristos unsigned int ohash_entries(struct ohash *); 65*71dafaa1Schristos 66*71dafaa1Schristos void *ohash_create_entry(struct ohash_info *, const char *, const char **); 67*71dafaa1Schristos u_int32_t ohash_interval(const char *, const char **); 68*71dafaa1Schristos 69*71dafaa1Schristos unsigned int ohash_qlookupi(struct ohash *, const char *, const char **); 70*71dafaa1Schristos unsigned int ohash_qlookup(struct ohash *, const char *); 71*71dafaa1Schristos __END_DECLS 72*71dafaa1Schristos #endif 73*71dafaa1Schristos 74