summaryrefslogtreecommitdiffstats
path: root/bin/sh/arith.y
blob: 391cc1618cc23c1a37341aa33fd581f50c63b261 (plain)
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
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
%{
/*-
 * 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.
 * 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.
 */

#if 0
#ifndef lint
static char sccsid[] = "@(#)arith.y	8.3 (Berkeley) 5/4/95";
#endif
#endif /* not lint */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include <limits.h>
#include <stdio.h>

#include "arith.h"
#include "shell.h"
#include "var.h"
%}
%union {
	arith_t l_value;
	char* s_value;
}
%token <l_value> ARITH_NUM ARITH_LPAREN ARITH_RPAREN
%token <s_value> ARITH_VAR

%type <l_value>	expr
%right ARITH_ASSIGN
%right ARITH_ADDASSIGN ARITH_SUBASSIGN
%right ARITH_MULASSIGN ARITH_DIVASSIGN ARITH_REMASSIGN
%right ARITH_RSHASSIGN ARITH_LSHASSIGN
%right ARITH_BANDASSIGN ARITH_BXORASSIGN ARITH_BORASSIGN
%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 |
	ARITH_VAR
		{
		char *p;
		arith_t arith_val;
		char *str_val;

		if (lookupvar($1) == NULL)
			setvarsafe($1, "0", 0);
		str_val = lookupvar($1);
		arith_val = strtoarith_t(str_val, &p, 0);
		/*
		 * Conversion is successful only in case
		 * we've converted _all_ characters.
		 */
		if (*p != '\0')
			yyerror("variable conversion error");
		$$ = arith_val;
		} |
	ARITH_VAR ARITH_ASSIGN expr
		{
		if (arith_assign($1, $3) != 0)
			yyerror("variable assignment error");
		$$ = $3;
		} |
	ARITH_VAR ARITH_ADDASSIGN expr
		{
		arith_t value;

		value = atoarith_t(lookupvar($1)) + $3;
		if (arith_assign($1, value) != 0)
			yyerror("variable assignment error");
		$$ = value;
		} |
	ARITH_VAR ARITH_SUBASSIGN expr
		{
		arith_t value;

		value = atoarith_t(lookupvar($1)) - $3;
		if (arith_assign($1, value) != 0)
			yyerror("variable assignment error");
		$$ = value;
		} |
	ARITH_VAR ARITH_MULASSIGN expr
		{
		arith_t value;

		value = atoarith_t(lookupvar($1)) * $3;
		if (arith_assign($1, value) != 0)
			yyerror("variable assignment error");
		$$ = value;
		} |
	ARITH_VAR ARITH_DIVASSIGN expr
		{
		arith_t value;

		if ($3 == 0)
			yyerror("division by zero");

		value = atoarith_t(lookupvar($1)) / $3;
		if (arith_assign($1, value) != 0)
			yyerror("variable assignment error");
		$$ = value;
		} |
	ARITH_VAR ARITH_REMASSIGN expr
		{
		arith_t value;

		if ($3 == 0)
			yyerror("division by zero");

		value = atoarith_t(lookupvar($1)) % $3;
		if (arith_assign($1, value) != 0)
			yyerror("variable assignment error");
		$$ = value;
		} |
	ARITH_VAR ARITH_RSHASSIGN expr
		{
		arith_t value;

		value = atoarith_t(lookupvar($1)) >> $3;
		if (arith_assign($1, value) != 0)
			yyerror("variable assignment error");
		$$ = value;
		} |
	ARITH_VAR ARITH_LSHASSIGN expr
		{
		arith_t value;

		value = atoarith_t(lookupvar($1)) << $3;
		if (arith_assign($1, value) != 0)
			yyerror("variable assignment error");
		$$ = value;
		} |
	ARITH_VAR ARITH_BANDASSIGN expr
		{
		arith_t value;

		value = atoarith_t(lookupvar($1)) & $3;
		if (arith_assign($1, value) != 0)
			yyerror("variable assignment error");
		$$ = value;
		} |
	ARITH_VAR ARITH_BXORASSIGN expr
		{
		arith_t value;

		value = atoarith_t(lookupvar($1)) ^ $3;
		if (arith_assign($1, value) != 0)
			yyerror("variable assignment error");
		$$ = value;
		} |
	ARITH_VAR ARITH_BORASSIGN expr
		{
		arith_t value;

		value = atoarith_t(lookupvar($1)) | $3;
		if (arith_assign($1, value) != 0)
			yyerror("variable assignment error");
		$$ = value;
		} ;
%%
#include "error.h"
#include "output.h"
#include "memalloc.h"

#define lstrlen(var) (3 + (2 + CHAR_BIT * sizeof((var))) / 3)

char *arith_buf, *arith_startbuf;

int yylex(void);
int yyparse(void);

static int
arith_assign(char *name, arith_t value)
{
	char *str;
	int ret;

	str = (char *)ckmalloc(lstrlen(value));
	sprintf(str, ARITH_FORMAT_STR, value);
	ret = setvarsafe(name, str, 0);
	free(str);
	return ret;
}

int
arith(char *s)
{
	long result;

	arith_buf = arith_startbuf = s;

	INTOFF;
	result = yyparse();
	arith_lex_reset();	/* Reprime lex. */
	INTON;

	return result;
}

static void
yyerror(char *s)
{

	yyerrok;
	yyclearin;
	arith_lex_reset();	/* Reprime lex. */
	error("arithmetic expression: %s: \"%s\"", s, arith_startbuf);
}

/*
 *  The exp(1) builtin.
 */
int
expcmd(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("%ld\n", i);
	return !i;
}

/*************************/
#ifdef TEST_ARITH
#include <stdio.h>
main(int argc, char *argv[])
{
	printf("%d\n", exp(argv[1]));
}

error(char *s)
{
	fprintf(stderr, "exp: %s\n", s);
	exit(1);
}
#endif
OpenPOWER on IntegriCloud