1 /* 2 * Copyright (c) 1983, 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 * Edward Wang at The University of California, Berkeley. 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 * @(#)parser1.c 8.1 (Berkeley) 6/6/93 37 * $FreeBSD: src/usr.bin/window/parser1.c,v 1.1.1.1.14.1 2001/05/17 09:45:00 obrien Exp $ 38 * $DragonFly: src/usr.bin/window/parser1.c,v 1.2 2003/06/17 04:29:34 dillon Exp $ 39 */ 40 41 #include "parser.h" 42 43 p_start() 44 { 45 char flag = 1; 46 47 (void) s_gettok(); 48 for (;;) { 49 p_statementlist(flag); 50 if (token == T_EOF || p_abort()) 51 break; 52 flag = 0; 53 p_synerror(); 54 while (token != T_EOL && token != T_EOF) { 55 if (token == T_STR) 56 str_free(token_str); 57 (void) s_gettok(); 58 } 59 if (token == T_EOL) 60 (void) s_gettok(); 61 p_clearerr(); 62 } 63 } 64 65 p_statementlist(flag) 66 char flag; 67 { 68 for (; p_statement(flag) >= 0; p_clearerr()) 69 ; 70 } 71 72 p_statement(flag) 73 char flag; 74 { 75 switch (token) { 76 case T_EOL: 77 (void) s_gettok(); 78 return 0; 79 case T_IF: 80 return p_if(flag); 81 default: 82 return p_expression(flag); 83 } 84 } 85 86 p_if(flag) 87 char flag; 88 { 89 struct value t; 90 char true = 0; 91 92 top: 93 (void) s_gettok(); 94 95 if (p_expr(&t, flag) < 0) { 96 p_synerror(); 97 return -1; 98 } 99 switch (t.v_type) { 100 case V_NUM: 101 true = !true && t.v_num != 0; 102 break; 103 case V_STR: 104 p_error("if: Numeric value required."); 105 str_free(t.v_str); 106 case V_ERR: 107 flag = 0; 108 break; 109 } 110 111 if (token != T_THEN) { 112 p_synerror(); 113 return -1; 114 } 115 116 (void) s_gettok(); 117 p_statementlist(flag && true); 118 if (p_erred()) 119 return -1; 120 121 if (token == T_ELSIF) 122 goto top; 123 124 if (token == T_ELSE) { 125 (void) s_gettok(); 126 p_statementlist(flag && !true); 127 if (p_erred()) 128 return -1; 129 } 130 131 if (token == T_ENDIF) { 132 (void) s_gettok(); 133 return 0; 134 } 135 136 p_synerror(); 137 return -1; 138 } 139 140 p_expression(flag) 141 char flag; 142 { 143 struct value t; 144 char *cmd; 145 int p_function(), p_assign(); 146 147 switch (token) { 148 case T_NUM: 149 t.v_type = V_NUM; 150 t.v_num = token_num; 151 (void) s_gettok(); 152 break; 153 case T_STR: 154 t.v_type = V_STR; 155 t.v_str = token_str; 156 (void) s_gettok(); 157 break; 158 default: 159 if (p_expr(&t, flag) < 0) 160 return -1; 161 if (token == T_EOF) { 162 val_free(t); 163 return 0; 164 } 165 } 166 if (token != T_ASSIGN && p_convstr(&t) < 0) 167 return -1; 168 cmd = t.v_type == V_STR ? t.v_str : 0; 169 if ((*(token == T_ASSIGN ? p_assign : p_function))(cmd, &t, flag) < 0) { 170 if (cmd) 171 str_free(cmd); 172 return -1; 173 } 174 if (cmd) 175 str_free(cmd); 176 val_free(t); 177 if (token == T_EOL) 178 (void) s_gettok(); 179 else if (token != T_EOF) { 180 p_synerror(); 181 return -1; 182 } 183 return 0; 184 } 185 186 p_convstr(v) 187 register struct value *v; 188 { 189 if (v->v_type != V_NUM) 190 return 0; 191 if ((v->v_str = str_itoa(v->v_num)) == 0) { 192 p_memerror(); 193 v->v_type = V_ERR; 194 return -1; 195 } 196 v->v_type = V_STR; 197 return 0; 198 } 199 200 p_synerror() 201 { 202 if (!cx.x_synerred) { 203 cx.x_synerred = cx.x_erred = 1; 204 error("Syntax error."); 205 } 206 } 207 208 /*VARARGS1*/ 209 p_error(msg, a, b, c) 210 char *msg; 211 { 212 if (!cx.x_erred) { 213 cx.x_erred = 1; 214 error(msg, a, b, c); 215 } 216 } 217 218 p_memerror() 219 { 220 cx.x_erred = cx.x_abort = 1; 221 error("Out of memory."); 222 } 223