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
p_expr(struct value * v,char flag)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 /* FALLTHROUGH */
71 case V_ERR:
72 t.v_str = 0;
73 break;
74 }
75 ret = p_assign(t.v_str, v, flag);
76 if (t.v_str != 0)
77 str_free(t.v_str);
78 return ret;
79 }
80
81 /*
82 * ? :
83 */
84 int
p_expr0(struct value * v,char flag)85 p_expr0(struct value *v, char flag)
86 {
87 struct value t;
88 char true = 0;
89
90 if (p_expr1(v, flag) < 0)
91 return -1;
92 if (token != T_QUEST)
93 return 0;
94 switch (v->v_type) {
95 case V_NUM:
96 true = v->v_num != 0;
97 break;
98 case V_STR:
99 p_error("?: Numeric left operand required.");
100 str_free(v->v_str);
101 v->v_type = V_ERR;
102 /* FALLTHROUGH */
103 case V_ERR:
104 flag = 0;
105 break;
106 }
107 (void) s_gettok();
108 v->v_type = V_ERR;
109 if ((flag && true ? p_expr1(v, 1) : p_expr1(&t, 0)) < 0)
110 return -1;
111 if (token != T_COLON) {
112 val_free(*v);
113 p_synerror();
114 return -1;
115 }
116 (void) s_gettok();
117 return flag && !true ? p_expr1(v, 1) : p_expr1(&t, 0);
118 }
119
120 /*
121 * ||
122 */
123 int
p_expr1(struct value * v,char flag)124 p_expr1(struct value *v, char flag)
125 {
126 char true = 0;
127
128 if (p_expr2(v, flag) < 0)
129 return -1;
130 if (token != T_OROR)
131 return 0;
132 for (;;) {
133 switch (v->v_type) {
134 case V_NUM:
135 v->v_num = true = true || v->v_num != 0;
136 break;
137 case V_STR:
138 p_error("||: Numeric operands required.");
139 str_free(v->v_str);
140 v->v_type = V_ERR;
141 /* FALLTHROUGH */
142 case V_ERR:
143 flag = 0;
144 break;
145 }
146 if (token != T_OROR)
147 return 0;
148 (void) s_gettok();
149 if (p_expr2(v, flag && !true) < 0)
150 return -1;
151 }
152 }
153
154 /*
155 * &&
156 */
157 int
p_expr2(struct value * v,char flag)158 p_expr2(struct value *v, char flag)
159 {
160 char true = 1;
161
162 if (p_expr3_10(3, v, flag) < 0)
163 return -1;
164 if (token != T_ANDAND)
165 return 0;
166 for (;;) {
167 switch (v->v_type) {
168 case V_NUM:
169 v->v_num = true = true && v->v_num != 0;
170 break;
171 case V_STR:
172 p_error("&&: Numeric operands required.");
173 str_free(v->v_str);
174 v->v_type = V_ERR;
175 /* FALLTHROUGH */
176 case V_ERR:
177 flag = 0;
178 break;
179 }
180 if (token != T_ANDAND)
181 return 0;
182 (void) s_gettok();
183 if (p_expr3_10(3, v, flag && true) < 0)
184 return -1;
185 }
186 /*NOTREACHED*/
187 }
188