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Diffstat (limited to 'bin/sh/arith.y')
| -rw-r--r-- | bin/sh/arith.y | 169 |
1 files changed, 169 insertions, 0 deletions
diff --git a/bin/sh/arith.y b/bin/sh/arith.y new file mode 100644 index 0000000..4b2e78f --- /dev/null +++ b/bin/sh/arith.y @@ -0,0 +1,169 @@ +%token ARITH_OR ARITH_AND ARITH_ADD ARITH_SUBT ARITH_MULT ARITH_DIV ARITH_REM ARITH_EQ ARITH_GT ARITH_GEQ ARITH_LT ARITH_LEQ ARITH_NEQ +%token ARITH_NUM ARITH_LPAREN ARITH_RPAREN ARITH_NOT ARITH_UNARYMINUS + +%left ARITH_OR +%left ARITH_AND +%left ARITH_EQ ARITH_NEQ +%left ARITH_LT ARITH_GT ARITH_GEQ ARITH_LEQ +%left ARITH_ADD ARITH_SUBT +%left ARITH_MULT ARITH_DIV ARITH_REM +%left ARITH_UNARYMINUS ARITH_NOT +%% + +exp: expr = { + return ($1); + } + ; + + +expr: ARITH_LPAREN expr ARITH_RPAREN = { $$ = $2; } + | expr ARITH_OR expr = { $$ = $1 ? $1 : $3 ? $3 : 0; } + | expr ARITH_AND expr = { $$ = $1 ? ( $3 ? $3 : 0 ) : 0; } + | expr ARITH_EQ expr = { $$ = $1 == $3; } + | expr ARITH_GT expr = { $$ = $1 > $3; } + | expr ARITH_GEQ expr = { $$ = $1 >= $3; } + | expr ARITH_LT expr = { $$ = $1 < $3; } + | expr ARITH_LEQ expr = { $$ = $1 <= $3; } + | expr ARITH_NEQ expr = { $$ = $1 != $3; } + | expr ARITH_ADD expr = { $$ = $1 + $3; } + | expr ARITH_SUBT expr = { $$ = $1 - $3; } + | expr ARITH_MULT expr = { $$ = $1 * $3; } + | expr ARITH_DIV expr = { + if ($3 == 0) + yyerror("division by zero"); + $$ = $1 / $3; + } + | expr ARITH_REM expr = { $$ = $1 % $3; } + | ARITH_NOT expr = { $$ = !($2); } + | ARITH_UNARYMINUS expr = { $$ = -($2); } + | ARITH_NUM + ; +%% +/*- + * 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 +static char sccsid[] = "@(#)arith.y 8.1 (Berkeley) 5/31/93"; +#endif /* not lint */ + +#include "shell.h" +#include "error.h" +#include "output.h" +#include "memalloc.h" + +char *arith_buf, *arith_startbuf; + +arith(s) + char *s; +{ + extern arith_wasoper; + long result; + + arith_wasoper = 1; + arith_buf = arith_startbuf = s; + + INTOFF; + result = yyparse(); + arith_lex_reset(); /* reprime lex */ + INTON; + + return (result); +} + +yyerror(s) + char *s; +{ + extern yytext, yylval; + + yyerrok; + yyclearin; + arith_lex_reset(); /* reprime lex */ + error("arithmetic expression: %s: \"%s\"", s, arith_startbuf); +} + +/* + * The exp(1) builtin. + */ +expcmd(argc, argv) + 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 |
