1 #ifndef OHASH_H 2 #define OHASH_H 3 /* $MirOS: src/include/ohash.h,v 1.2 2013/10/31 20:06:07 tg Exp $ */ 4 /* $OpenBSD: ohash.h,v 1.7 2004/06/22 20:00:16 espie Exp $ */ 5 /* ex:ts=8 sw=4: 6 */ 7 8 /* Copyright (c) 1999, 2004 Marc Espie <espie@openbsd.org> 9 * Copyright © 2013 10 * Thorsten “mirabilos” Glaser <tg@mirbsd.org> 11 * 12 * Permission to use, copy, modify, and distribute this software for any 13 * purpose with or without fee is hereby granted, provided that the above 14 * copyright notice and this permission notice appear in all copies. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 17 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 18 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 19 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 20 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 21 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 22 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 23 */ 24 25 /* Open hashing support. 26 * Open hashing was chosen because it is much lighter than other hash 27 * techniques, and more efficient in most cases. 28 */ 29 30 struct ohash_info { 31 ptrdiff_t key_offset; 32 void *data; /* user data */ 33 void *(*halloc)(size_t, void *); 34 void (*hfree)(void *, size_t, void *); 35 void *(*alloc)(size_t, void *); 36 }; 37 38 struct _ohash_record; 39 40 struct ohash { 41 struct _ohash_record *t; 42 struct ohash_info info; 43 unsigned int size; 44 unsigned int total; 45 unsigned int deleted; 46 }; 47 48 /* For this to be tweakable, we use small primitives, and leave part of the 49 * logic to the client application. e.g., hashing is left to the client 50 * application. We also provide a simple table entry lookup that yields 51 * a hashing table index (opaque) to be used in find/insert/remove. 52 * The keys are stored at a known position in the client data. 53 */ 54 __BEGIN_DECLS 55 void ohash_init(struct ohash *, unsigned, struct ohash_info *); 56 void ohash_delete(struct ohash *); 57 58 unsigned int ohash_lookup_string(struct ohash *, const char *, u_int32_t); 59 unsigned int ohash_lookup_interval(struct ohash *, const char *, 60 const char *, u_int32_t); 61 unsigned int ohash_lookup_memory(struct ohash *, const char *, 62 size_t, u_int32_t) 63 __attribute__((__bounded__(__string__, 2, 3))); 64 void *ohash_find(struct ohash *, unsigned int); 65 void *ohash_remove(struct ohash *, unsigned int); 66 void *ohash_insert(struct ohash *, unsigned int, void *); 67 void *ohash_first(struct ohash *, unsigned int *); 68 void *ohash_next(struct ohash *, unsigned int *); 69 unsigned int ohash_entries(struct ohash *); 70 71 void *ohash_create_entry(struct ohash_info *, const char *, const char **); 72 u_int32_t ohash_interval(const char *, const char **); 73 74 unsigned int ohash_qlookupi(struct ohash *, const char *, const char **); 75 unsigned int ohash_qlookup(struct ohash *, const char *); 76 __END_DECLS 77 #endif 78