1 /* $NetBSD: hash.h,v 1.6 2002/06/15 18:24:56 wiz Exp $ */ 2 3 /* 4 * Copyright (c) 1988, 1989, 1990 The Regents of the University of California. 5 * Copyright (c) 1988, 1989 by Adam de Boor 6 * Copyright (c) 1989 by Berkeley Softworks 7 * All rights reserved. 8 * 9 * This code is derived from software contributed to Berkeley by 10 * Adam de Boor. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by the University of 23 * California, Berkeley and its contributors. 24 * 4. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 39 * 40 * from: @(#)hash.h 8.1 (Berkeley) 6/6/93 41 */ 42 43 /* hash.h -- 44 * 45 * This file contains definitions used by the hash module, 46 * which maintains hash tables. 47 */ 48 49 #ifndef _HASH 50 #define _HASH 51 52 /* 53 * The following defines one entry in the hash table. 54 */ 55 56 typedef struct Hash_Entry { 57 struct Hash_Entry *next; /* Used to link together all the 58 * entries associated with the same 59 * bucket. */ 60 ClientData clientData; /* Arbitrary piece of data associated 61 * with key. */ 62 unsigned namehash; /* hash value of key */ 63 char name[1]; /* key string */ 64 } Hash_Entry; 65 66 typedef struct Hash_Table { 67 struct Hash_Entry **bucketPtr;/* Pointers to Hash_Entry, one 68 * for each bucket in the table. */ 69 int size; /* Actual size of array. */ 70 int numEntries; /* Number of entries in the table. */ 71 int mask; /* Used to select bits for hashing. */ 72 } Hash_Table; 73 74 /* 75 * The following structure is used by the searching routines 76 * to record where we are in the search. 77 */ 78 79 typedef struct Hash_Search { 80 Hash_Table *tablePtr; /* Table being searched. */ 81 int nextIndex; /* Next bucket to check (after current). */ 82 Hash_Entry *hashEntryPtr; /* Next entry to check in current bucket. */ 83 } Hash_Search; 84 85 /* 86 * Macros. 87 */ 88 89 /* 90 * ClientData Hash_GetValue(h) 91 * Hash_Entry *h; 92 */ 93 94 #define Hash_GetValue(h) ((h)->clientData) 95 96 /* 97 * Hash_SetValue(h, val); 98 * Hash_Entry *h; 99 * char *val; 100 */ 101 102 #define Hash_SetValue(h, val) ((h)->clientData = (ClientData) (val)) 103 104 /* 105 * Hash_Size(n) returns the number of words in an object of n bytes 106 */ 107 108 #define Hash_Size(n) (((n) + sizeof (int) - 1) / sizeof (int)) 109 110 void Hash_InitTable(Hash_Table *, int); 111 void Hash_DeleteTable(Hash_Table *); 112 Hash_Entry *Hash_FindEntry(Hash_Table *, char *); 113 Hash_Entry *Hash_CreateEntry(Hash_Table *, char *, Boolean *); 114 void Hash_DeleteEntry(Hash_Table *, Hash_Entry *); 115 Hash_Entry *Hash_EnumFirst(Hash_Table *, Hash_Search *); 116 Hash_Entry *Hash_EnumNext(Hash_Search *); 117 118 #endif /* _HASH */ 119