1 /* $NetBSD: lookup.c,v 1.9 2009/04/13 04:35:36 lukem Exp $ */ 2 3 /* 4 * Copyright (c) 1983, 1993 5 * The Regents of the University of California. 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. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 #ifndef lint 34 #if 0 35 static char sccsid[] = "@(#)lookup.c 8.1 (Berkeley) 6/9/93"; 36 #else 37 __RCSID("$NetBSD: lookup.c,v 1.9 2009/04/13 04:35:36 lukem Exp $"); 38 #endif 39 #endif /* not lint */ 40 41 #include "defs.h" 42 43 /* symbol types */ 44 #define VAR 1 45 #define CONST 2 46 47 struct syment { 48 int s_type; 49 char *s_name; 50 struct namelist *s_value; 51 struct syment *s_next; 52 }; 53 54 static struct syment *hashtab[HASHSIZE]; 55 56 /* 57 * Define a variable from a command line argument. 58 */ 59 void 60 define(char *name) 61 { 62 char *cp, *s; 63 struct namelist *nl; 64 struct namelist *value; 65 66 value = NULL; 67 68 if (debug) 69 printf("define(%s)\n", name); 70 71 cp = strchr(name, '='); 72 if (cp == NULL) 73 value = NULL; 74 else if (cp[1] == '\0') { 75 *cp = '\0'; 76 value = NULL; 77 } else if (cp[1] != '(') { 78 *cp++ = '\0'; 79 value = makenl(cp); 80 } else { 81 nl = NULL; 82 *cp++ = '\0'; 83 do 84 cp++; 85 while (*cp == ' ' || *cp == '\t'); 86 for (s = cp; ; s++) { 87 switch (*s) { 88 case ')': 89 *s = '\0'; 90 case '\0': 91 break; 92 case ' ': 93 case '\t': 94 *s++ = '\0'; 95 while (*s == ' ' || *s == '\t') 96 s++; 97 if (*s == ')') 98 *s = '\0'; 99 break; 100 default: 101 continue; 102 } 103 if (nl == NULL) 104 value = nl = makenl(cp); 105 else { 106 nl->n_next = makenl(cp); 107 nl = nl->n_next; 108 } 109 if (*s == '\0') 110 break; 111 cp = s; 112 } 113 } 114 (void) lookup(name, REPLACE, value); 115 } 116 117 /* 118 * Lookup name in the table and return a pointer to it. 119 * LOOKUP - just do lookup, return NULL if not found. 120 * INSERT - insert name with value, error if already defined. 121 * REPLACE - insert or replace name with value. 122 */ 123 124 struct namelist * 125 lookup(char *name, int action, struct namelist *value) 126 { 127 unsigned n; 128 char *cp; 129 struct syment *s; 130 char lbuf[256]; 131 132 if (debug) 133 printf("lookup(%s, %d, %lx)\n", name, action, (long)value); 134 135 n = 0; 136 for (cp = name; *cp; ) 137 n += *cp++; 138 n %= HASHSIZE; 139 140 for (s = hashtab[n]; s != NULL; s = s->s_next) { 141 if (strcmp(name, s->s_name)) 142 continue; 143 if (action != LOOKUP) { 144 if (action != INSERT || s->s_type != CONST) { 145 (void)snprintf(lbuf, sizeof(lbuf), 146 "%s redefined", name); 147 yyerror(lbuf); 148 } 149 } 150 return(s->s_value); 151 } 152 153 if (action == LOOKUP) { 154 (void)snprintf(lbuf, sizeof(lbuf), "%s undefined", name); 155 yyerror(lbuf); 156 return(NULL); 157 } 158 159 s = ALLOC(syment); 160 if (s == NULL) 161 fatal("ran out of memory\n"); 162 s->s_next = hashtab[n]; 163 hashtab[n] = s; 164 s->s_type = action == INSERT ? VAR : CONST; 165 s->s_name = name; 166 s->s_value = value; 167 return(value); 168 } 169