1 /* $NetBSD: hash.c,v 1.9 2004/06/20 22:20:17 jmc Exp $ */ 2 3 /* 4 * Copyright (c) 1994, 1995 Jochen Pohl 5 * All Rights Reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by Jochen Pohl for 18 * The NetBSD Project. 19 * 4. The name of the author may not be used to endorse or promote products 20 * derived from this software without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 #if HAVE_NBTOOL_CONFIG_H 35 #include "nbtool_config.h" 36 #endif 37 38 #include <sys/cdefs.h> 39 #if defined(__RCSID) && !defined(lint) 40 __RCSID("$NetBSD: hash.c,v 1.9 2004/06/20 22:20:17 jmc Exp $"); 41 #endif 42 43 /* 44 * XXX Really need a generalized hash table package 45 */ 46 47 #include <limits.h> 48 #include <stddef.h> 49 #include <stdlib.h> 50 #include <string.h> 51 52 #include "lint2.h" 53 54 /* pointer to hash table, initialized in inithash() */ 55 static hte_t **htab; 56 57 static int hash(const char *); 58 59 /* 60 * Initialize hash table. 61 */ 62 void 63 _inithash(hte_t ***tablep) 64 { 65 66 if (tablep == NULL) 67 tablep = &htab; 68 69 *tablep = xcalloc(HSHSIZ2, sizeof (hte_t *)); 70 } 71 72 /* 73 * Compute hash value from a string. 74 */ 75 static int 76 hash(const char *s) 77 { 78 u_int v; 79 const u_char *us; 80 81 v = 0; 82 for (us = (const u_char *)s; *us != '\0'; us++) { 83 v = (v << sizeof (v)) + *us; 84 v ^= v >> (sizeof (v) * CHAR_BIT - sizeof (v)); 85 } 86 return (v % HSHSIZ2); 87 } 88 89 /* 90 * Look for a hash table entry. If no hash table entry for the 91 * given name exists and mknew is set, create a new one. 92 */ 93 hte_t * 94 _hsearch(hte_t **table, const char *s, int mknew) 95 { 96 int h; 97 hte_t *hte; 98 99 if (table == NULL) 100 table = htab; 101 102 h = hash(s); 103 for (hte = table[h]; hte != NULL; hte = hte->h_link) { 104 if (strcmp(hte->h_name, s) == 0) 105 break; 106 } 107 108 if (hte != NULL || !mknew) 109 return (hte); 110 111 /* create a new hte */ 112 hte = xmalloc(sizeof (hte_t)); 113 hte->h_name = xstrdup(s); 114 hte->h_used = 0; 115 hte->h_def = 0; 116 hte->h_static = 0; 117 hte->h_syms = NULL; 118 hte->h_lsym = &hte->h_syms; 119 hte->h_calls = NULL; 120 hte->h_lcall = &hte->h_calls; 121 hte->h_usyms = NULL; 122 hte->h_lusym = &hte->h_usyms; 123 hte->h_link = table[h]; 124 hte->h_hte = NULL; 125 table[h] = hte; 126 127 return (hte); 128 } 129 130 /* 131 * Call function f for each name in the hash table. 132 */ 133 void 134 _forall(hte_t **table, void (*f)(hte_t *)) 135 { 136 int i; 137 hte_t *hte; 138 139 if (table == NULL) 140 table = htab; 141 142 for (i = 0; i < HSHSIZ2; i++) { 143 for (hte = table[i]; hte != NULL; hte = hte->h_link) 144 (*f)(hte); 145 } 146 } 147 148 /* 149 * Free all contents of the hash table that this module allocated. 150 */ 151 void 152 _destroyhash(hte_t **table) 153 { 154 int i; 155 hte_t *hte, *nexthte; 156 157 if (table == NULL) 158 err(1, "_destroyhash called on main hash table"); 159 160 for (i = 0; i < HSHSIZ2; i++) { 161 for (hte = table[i]; hte != NULL; hte = nexthte) { 162 free((void *)hte->h_name); 163 nexthte = hte->h_link; 164 free(hte); 165 } 166 } 167 free(table); 168 } 169