1 /* 2 * Copyright (c) 1983 Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #ifndef lint 35 /*static char sccsid[] = "from: @(#)lookup.c 5.5 (Berkeley) 6/1/90";*/ 36 static char rcsid[] = "$Id: lookup.c,v 1.2 1993/08/01 18:09:43 mycroft Exp $"; 37 #endif /* not lint */ 38 39 #include "defs.h" 40 41 /* symbol types */ 42 #define VAR 1 43 #define CONST 2 44 45 struct syment { 46 int s_type; 47 char *s_name; 48 struct namelist *s_value; 49 struct syment *s_next; 50 }; 51 52 static struct syment *hashtab[HASHSIZE]; 53 54 /* 55 * Define a variable from a command line argument. 56 */ 57 define(name) 58 char *name; 59 { 60 register char *cp, *s; 61 register struct namelist *nl; 62 struct namelist *value; 63 64 if (debug) 65 printf("define(%s)\n", name); 66 67 cp = index(name, '='); 68 if (cp == NULL) 69 value = NULL; 70 else if (cp[1] == '\0') { 71 *cp = '\0'; 72 value = NULL; 73 } else if (cp[1] != '(') { 74 *cp++ = '\0'; 75 value = makenl(cp); 76 } else { 77 nl = NULL; 78 *cp++ = '\0'; 79 do 80 cp++; 81 while (*cp == ' ' || *cp == '\t'); 82 for (s = cp; ; s++) { 83 switch (*s) { 84 case ')': 85 *s = '\0'; 86 case '\0': 87 break; 88 case ' ': 89 case '\t': 90 *s++ = '\0'; 91 while (*s == ' ' || *s == '\t') 92 s++; 93 if (*s == ')') 94 *s = '\0'; 95 break; 96 default: 97 continue; 98 } 99 if (nl == NULL) 100 value = nl = makenl(cp); 101 else { 102 nl->n_next = makenl(cp); 103 nl = nl->n_next; 104 } 105 if (*s == '\0') 106 break; 107 cp = s; 108 } 109 } 110 (void) lookup(name, REPLACE, value); 111 } 112 113 /* 114 * Lookup name in the table and return a pointer to it. 115 * LOOKUP - just do lookup, return NULL if not found. 116 * INSERT - insert name with value, error if already defined. 117 * REPLACE - insert or replace name with value. 118 */ 119 120 struct namelist * 121 lookup(name, action, value) 122 char *name; 123 int action; 124 struct namelist *value; 125 { 126 register unsigned n; 127 register char *cp; 128 register struct syment *s; 129 char buf[256]; 130 131 if (debug) 132 printf("lookup(%s, %d, %x)\n", name, action, value); 133 134 n = 0; 135 for (cp = name; *cp; ) 136 n += *cp++; 137 n %= HASHSIZE; 138 139 for (s = hashtab[n]; s != NULL; s = s->s_next) { 140 if (strcmp(name, s->s_name)) 141 continue; 142 if (action != LOOKUP) { 143 if (action != INSERT || s->s_type != CONST) { 144 (void)sprintf(buf, "%s redefined", name); 145 yyerror(buf); 146 } 147 } 148 return(s->s_value); 149 } 150 151 if (action == LOOKUP) { 152 (void)sprintf(buf, "%s undefined", name); 153 yyerror(buf); 154 return(NULL); 155 } 156 157 s = ALLOC(syment); 158 if (s == NULL) 159 fatal("ran out of memory\n"); 160 s->s_next = hashtab[n]; 161 hashtab[n] = s; 162 s->s_type = action == INSERT ? VAR : CONST; 163 s->s_name = name; 164 s->s_value = value; 165 return(value); 166 } 167