1 /* 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Ozan Yigit at York University. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #include <sys/cdefs.h> 38 #ifndef lint 39 #if 0 40 static char sccsid[] = "@(#)look.c 8.1 (Berkeley) 6/6/93"; 41 #else 42 __RCSID("$NetBSD: look.c,v 1.6 1997/10/19 04:39:57 lukem Exp $"); 43 #endif 44 #endif /* not lint */ 45 46 /* 47 * look.c 48 * Facility: m4 macro processor 49 * by: oz 50 */ 51 52 #include <sys/types.h> 53 #include <stdio.h> 54 #include <stdlib.h> 55 #include <string.h> 56 #include "mdef.h" 57 #include "stdd.h" 58 #include "extern.h" 59 60 static void freent __P((ndptr)); 61 62 63 int 64 hash(name) 65 char *name; 66 { 67 unsigned long h = 0; 68 while (*name) 69 h = (h << 5) + h + *name++; 70 return (h % HASHSIZE); 71 } 72 73 /* 74 * find name in the hash table 75 */ 76 ndptr 77 lookup(name) 78 char *name; 79 { 80 ndptr p; 81 82 for (p = hashtab[hash(name)]; p != nil; p = p->nxtptr) 83 if (STREQ(name, p->name)) 84 break; 85 return (p); 86 } 87 88 /* 89 * hash and create an entry in the hash table. 90 * The new entry is added in front of a hash bucket. 91 */ 92 ndptr 93 addent(name) 94 char *name; 95 { 96 int h; 97 ndptr p; 98 99 h = hash(name); 100 p = (ndptr) xalloc(sizeof(struct ndblock)); 101 p->nxtptr = hashtab[h]; 102 hashtab[h] = p; 103 p->name = xstrdup(name); 104 return p; 105 } 106 107 static void 108 freent(p) 109 ndptr p; 110 { 111 if (!(p->type & STATIC)) { 112 free((char *) p->name); 113 if (p->defn != null) 114 free((char *) p->defn); 115 } 116 free((char *) p); 117 } 118 119 /* 120 * remove an entry from the hashtable 121 */ 122 void 123 remhash(name, all) 124 char *name; 125 int all; 126 { 127 int h; 128 ndptr xp, tp, mp; 129 130 h = hash(name); 131 mp = hashtab[h]; 132 tp = nil; 133 while (mp != nil) { 134 if (STREQ(mp->name, name)) { 135 mp = mp->nxtptr; 136 if (tp == nil) { 137 freent(hashtab[h]); 138 hashtab[h] = mp; 139 } 140 else { 141 xp = tp->nxtptr; 142 tp->nxtptr = mp; 143 freent(xp); 144 } 145 if (!all) 146 break; 147 } 148 else { 149 tp = mp; 150 mp = mp->nxtptr; 151 } 152 } 153 } 154