1 %{ 2 /* $OpenBSD: parser.y,v 1.7 2012/04/12 17:00:11 espie Exp $ */ 3 /* 4 * Copyright (c) 2004 Marc Espie <espie@cvs.openbsd.org> 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 * 18 * $FreeBSD$ 19 */ 20 21 #include <math.h> 22 #include <stdint.h> 23 #define YYSTYPE int32_t 24 extern int32_t end_result; 25 extern int yylex(void); 26 extern int yyerror(const char *); 27 %} 28 %token NUMBER 29 %token ERROR 30 %left LOR 31 %left LAND 32 %left '|' 33 %left '^' 34 %left '&' 35 %left EQ NE 36 %left '<' LE '>' GE 37 %left LSHIFT RSHIFT 38 %left '+' '-' 39 %left '*' '/' '%' 40 %right EXPONENT 41 %right UMINUS UPLUS '!' '~' 42 43 %% 44 45 top : expr { end_result = $1; } 46 ; 47 expr : expr '+' expr { $$ = $1 + $3; } 48 | expr '-' expr { $$ = $1 - $3; } 49 | expr EXPONENT expr { $$ = pow($1, $3); } 50 | expr '*' expr { $$ = $1 * $3; } 51 | expr '/' expr { 52 if ($3 == 0) { 53 yyerror("division by zero"); 54 exit(1); 55 } 56 $$ = $1 / $3; 57 } 58 | expr '%' expr { 59 if ($3 == 0) { 60 yyerror("modulo zero"); 61 exit(1); 62 } 63 $$ = $1 % $3; 64 } 65 | expr LSHIFT expr { $$ = $1 << $3; } 66 | expr RSHIFT expr { $$ = $1 >> $3; } 67 | expr '<' expr { $$ = $1 < $3; } 68 | expr '>' expr { $$ = $1 > $3; } 69 | expr LE expr { $$ = $1 <= $3; } 70 | expr GE expr { $$ = $1 >= $3; } 71 | expr EQ expr { $$ = $1 == $3; } 72 | expr NE expr { $$ = $1 != $3; } 73 | expr '&' expr { $$ = $1 & $3; } 74 | expr '^' expr { $$ = $1 ^ $3; } 75 | expr '|' expr { $$ = $1 | $3; } 76 | expr LAND expr { $$ = $1 && $3; } 77 | expr LOR expr { $$ = $1 || $3; } 78 | '(' expr ')' { $$ = $2; } 79 | '-' expr %prec UMINUS { $$ = -$2; } 80 | '+' expr %prec UPLUS { $$ = $2; } 81 | '!' expr { $$ = !$2; } 82 | '~' expr { $$ = ~$2; } 83 | NUMBER 84 ; 85 %% 86 87