1 /* $NetBSD: parser3.c,v 1.6 2003/08/07 11:17:28 agc Exp $ */ 2 3 /* 4 * Copyright (c) 1983, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Edward Wang at The University of California, Berkeley. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #include <sys/cdefs.h> 36 #ifndef lint 37 #if 0 38 static char sccsid[] = "@(#)parser3.c 8.1 (Berkeley) 6/6/93"; 39 #else 40 __RCSID("$NetBSD: parser3.c,v 1.6 2003/08/07 11:17:28 agc Exp $"); 41 #endif 42 #endif /* not lint */ 43 44 #include "defs.h" 45 #include "parser.h" 46 47 /* 48 * = 49 * ? : 50 * || 51 * && 52 * | 53 * ^ 54 * & 55 * == != 56 * <= >= 57 * << >> 58 * + - 59 * * / % 60 * unary - + ~ ! 61 */ 62 int 63 p_expr(struct value *v, char flag) 64 { 65 struct value t; 66 int ret; 67 68 if (p_expr0(&t, flag) < 0) 69 return -1; 70 71 if (token != T_ASSIGN) { 72 *v = t; 73 return 0; 74 } 75 switch (t.v_type) { 76 case V_NUM: 77 p_error("%d: Not a variable.", t.v_num); 78 case V_ERR: 79 t.v_str = 0; 80 break; 81 } 82 ret = p_assign(t.v_str, v, flag); 83 if (t.v_str != 0) 84 str_free(t.v_str); 85 return ret; 86 } 87 88 /* 89 * ? : 90 */ 91 int 92 p_expr0(struct value *v, char flag) 93 { 94 struct value t; 95 char true = 0; 96 97 if (p_expr1(v, flag) < 0) 98 return -1; 99 if (token != T_QUEST) 100 return 0; 101 switch (v->v_type) { 102 case V_NUM: 103 true = v->v_num != 0; 104 break; 105 case V_STR: 106 p_error("?: Numeric left operand required."); 107 str_free(v->v_str); 108 v->v_type = V_ERR; 109 case V_ERR: 110 flag = 0; 111 break; 112 } 113 (void) s_gettok(); 114 v->v_type = V_ERR; 115 if ((flag && true ? p_expr1(v, 1) : p_expr1(&t, 0)) < 0) 116 return -1; 117 if (token != T_COLON) { 118 val_free(*v); 119 p_synerror(); 120 return -1; 121 } 122 (void) s_gettok(); 123 return flag && !true ? p_expr1(v, 1) : p_expr1(&t, 0); 124 } 125 126 /* 127 * || 128 */ 129 int 130 p_expr1(struct value *v, char flag) 131 { 132 char true = 0; 133 134 if (p_expr2(v, flag) < 0) 135 return -1; 136 if (token != T_OROR) 137 return 0; 138 for (;;) { 139 switch (v->v_type) { 140 case V_NUM: 141 v->v_num = true = true || v->v_num != 0; 142 break; 143 case V_STR: 144 p_error("||: Numeric operands required."); 145 str_free(v->v_str); 146 v->v_type = V_ERR; 147 case V_ERR: 148 flag = 0; 149 break; 150 } 151 if (token != T_OROR) 152 return 0; 153 (void) s_gettok(); 154 if (p_expr2(v, flag && !true) < 0) 155 return -1; 156 } 157 } 158 159 /* 160 * && 161 */ 162 int 163 p_expr2(struct value *v, char flag) 164 { 165 char true = 1; 166 167 if (p_expr3_10(3, v, flag) < 0) 168 return -1; 169 if (token != T_ANDAND) 170 return 0; 171 for (;;) { 172 switch (v->v_type) { 173 case V_NUM: 174 v->v_num = true = true && v->v_num != 0; 175 break; 176 case V_STR: 177 p_error("&&: Numeric operands required."); 178 str_free(v->v_str); 179 v->v_type = V_ERR; 180 case V_ERR: 181 flag = 0; 182 break; 183 } 184 if (token != T_ANDAND) 185 return 0; 186 (void) s_gettok(); 187 if (p_expr3_10(3, v, flag && true) < 0) 188 return -1; 189 } 190 /*NOTREACHED*/ 191 } 192