1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
|
/* $OpenBSD: arith.y,v 1.3 1996/12/14 12:18:19 mickey Exp $ */
%token ARITH_NUM ARITH_LPAREN ARITH_RPAREN
%left ARITH_OR
%left ARITH_AND
%left ARITH_BOR
%left ARITH_BXOR
%left ARITH_BAND
%left ARITH_EQ ARITH_NE
%left ARITH_LT ARITH_GT ARITH_GE ARITH_LE
%left ARITH_LSHIFT ARITH_RSHIFT
%left ARITH_ADD ARITH_SUB
%left ARITH_MUL ARITH_DIV ARITH_REM
%left ARITH_UNARYMINUS ARITH_UNARYPLUS ARITH_NOT ARITH_BNOT
%%
exp: expr = {
return ($1);
}
;
expr: ARITH_LPAREN expr ARITH_RPAREN = { $$ = $2; }
| expr ARITH_OR expr = { $$ = $1 ? $1 : $3 ? $3 : 0; }
| expr ARITH_AND expr = { $$ = $1 ? ( $3 ? $3 : 0 ) : 0; }
| expr ARITH_BOR expr = { $$ = $1 | $3; }
| expr ARITH_BXOR expr = { $$ = $1 ^ $3; }
| expr ARITH_BAND expr = { $$ = $1 & $3; }
| expr ARITH_EQ expr = { $$ = $1 == $3; }
| expr ARITH_GT expr = { $$ = $1 > $3; }
| expr ARITH_GE expr = { $$ = $1 >= $3; }
| expr ARITH_LT expr = { $$ = $1 < $3; }
| expr ARITH_LE expr = { $$ = $1 <= $3; }
| expr ARITH_NE expr = { $$ = $1 != $3; }
| expr ARITH_LSHIFT expr = { $$ = $1 << $3; }
| expr ARITH_RSHIFT expr = { $$ = $1 >> $3; }
| expr ARITH_ADD expr = { $$ = $1 + $3; }
| expr ARITH_SUB expr = { $$ = $1 - $3; }
| expr ARITH_MUL expr = { $$ = $1 * $3; }
| expr ARITH_DIV expr = {
if ($3 == 0)
yyerror("division by zero");
$$ = $1 / $3;
}
| expr ARITH_REM expr = {
if ($3 == 0)
yyerror("division by zero");
$$ = $1 % $3;
}
| ARITH_NOT expr = { $$ = !($2); }
| ARITH_BNOT expr = { $$ = ~($2); }
| ARITH_SUB expr %prec ARITH_UNARYMINUS = { $$ = -($2); }
| ARITH_ADD expr %prec ARITH_UNARYPLUS = { $$ = $2; }
| ARITH_NUM
;
%%
/* $NetBSD: arith.y,v 1.6 1995/05/11 21:28:45 christos Exp $ */
/*-
* Copyright (c) 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Kenneth Almquist.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
#if 0
static char sccsid[] = "@(#)arith.y 8.3 (Berkeley) 5/4/95";
#else
static char sccsid[] = "$OpenBSD: arith.y,v 1.3 1996/12/14 12:18:19 mickey Exp $";
#endif
#endif /* not lint */
#include "shell.h"
#include "error.h"
#include "output.h"
#include "memalloc.h"
char *arith_buf, *arith_startbuf;
int yyparse __P((void));
int yylex __P((void));
int
arith(s)
char *s;
{
long result;
arith_buf = arith_startbuf = s;
INTOFF;
result = yyparse();
arith_lex_reset(); /* reprime lex */
INTON;
return (result);
}
void
yyerror(s)
char *s;
{
yyerrok;
yyclearin;
arith_lex_reset(); /* reprime lex */
error("arithmetic expression: %s: \"%s\"", s, arith_startbuf);
}
/*
* The exp(1) builtin.
*/
int
expcmd(argc, argv)
int argc;
char **argv;
{
char *p;
char *concat;
char **ap;
long i;
if (argc > 1) {
p = argv[1];
if (argc > 2) {
/*
* concatenate arguments
*/
STARTSTACKSTR(concat);
ap = argv + 2;
for (;;) {
while (*p)
STPUTC(*p++, concat);
if ((p = *ap++) == NULL)
break;
STPUTC(' ', concat);
}
STPUTC('\0', concat);
p = grabstackstr(concat);
}
} else
p = "";
i = arith(p);
out1fmt("%d\n", i);
return (! i);
}
/*************************/
#ifdef TEST_ARITH
#include <stdio.h>
main(argc, argv)
char *argv[];
{
printf("%d\n", exp(argv[1]));
}
error(s)
char *s;
{
fprintf(stderr, "exp: %s\n", s);
exit(1);
}
#endif
|
