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 #ifndef lint 38 static char sccsid[] = "@(#)look.c 8.1 (Berkeley) 6/6/93"; 39 static char rcsid[] = 40 "$FreeBSD$"; 41 #endif /* not lint */ 42 43 /* 44 * look.c 45 * Facility: m4 macro processor 46 * by: oz 47 */ 48 49 #include <sys/types.h> 50 #include <err.h> 51 #include <stdio.h> 52 #include <stdlib.h> 53 #include <string.h> 54 #include "mdef.h" 55 #include "stdd.h" 56 #include "extern.h" 57 58 int 59 hash(name) 60 register char *name; 61 { 62 register unsigned long h = 0; 63 while (*name) 64 h = (h << 5) + h + *name++; 65 return (h % HASHSIZE); 66 } 67 68 /* 69 * find name in the hash table 70 */ 71 ndptr 72 lookup(name) 73 char *name; 74 { 75 register ndptr p; 76 77 for (p = hashtab[hash(name)]; p != nil; p = p->nxtptr) 78 if (STREQ(name, p->name)) 79 break; 80 return (p); 81 } 82 83 /* 84 * hash and create an entry in the hash table. 85 * The new entry is added in front of a hash bucket. 86 */ 87 ndptr 88 addent(name) 89 char *name; 90 { 91 register int h; 92 ndptr p; 93 94 h = hash(name); 95 if ((p = malloc(sizeof(struct ndblock))) == NULL) 96 err(1, "malloc"); 97 p->nxtptr = hashtab[h]; 98 hashtab[h] = p; 99 if ((p->name = strdup(name)) == NULL) 100 err(1, "strdup"); 101 return p; 102 } 103 104 static void 105 freent(p) 106 ndptr p; 107 { 108 if (!(p->type & STATIC)) { 109 free((char *) p->name); 110 if (p->defn != null) 111 free((char *) p->defn); 112 } 113 free((char *) p); 114 } 115 116 /* 117 * remove an entry from the hashtable 118 */ 119 void 120 remhash(name, all) 121 char *name; 122 int all; 123 { 124 register int h; 125 register ndptr xp, tp, mp; 126 127 h = hash(name); 128 mp = hashtab[h]; 129 tp = nil; 130 while (mp != nil) { 131 if (STREQ(mp->name, name)) { 132 mp = mp->nxtptr; 133 if (tp == nil) { 134 freent(hashtab[h]); 135 hashtab[h] = mp; 136 } 137 else { 138 xp = tp->nxtptr; 139 tp->nxtptr = mp; 140 freent(xp); 141 } 142 if (!all) 143 break; 144 } 145 else { 146 tp = mp; 147 mp = mp->nxtptr; 148 } 149 } 150 } 151