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