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 19 #include <math.h> 20 #include <stdint.h> 21 #define YYSTYPE int32_t 22 extern int32_t end_result; 23 extern int yylex(void); 24 extern int yyerror(const char *); 25 %} 26 %token NUMBER 27 %token ERROR 28 %left LOR 29 %left LAND 30 %left '|' 31 %left '^' 32 %left '&' 33 %left EQ NE 34 %left '<' LE '>' GE 35 %left LSHIFT RSHIFT 36 %left '+' '-' 37 %left '*' '/' '%' 38 %right EXPONENT 39 %right UMINUS UPLUS '!' '~' 40 41 %% 42 43 top : expr { end_result = $1; } 44 ; 45 expr : expr '+' expr { $$ = $1 + $3; } 46 | expr '-' expr { $$ = $1 - $3; } 47 | expr EXPONENT expr { $$ = pow($1, $3); } 48 | expr '*' expr { $$ = $1 * $3; } 49 | expr '/' expr { 50 if ($3 == 0) { 51 yyerror("division by zero"); 52 exit(1); 53 } 54 $$ = $1 / $3; 55 } 56 | expr '%' expr { 57 if ($3 == 0) { 58 yyerror("modulo zero"); 59 exit(1); 60 } 61 $$ = $1 % $3; 62 } 63 | expr LSHIFT expr { $$ = $1 << $3; } 64 | expr RSHIFT expr { $$ = $1 >> $3; } 65 | expr '<' expr { $$ = $1 < $3; } 66 | expr '>' expr { $$ = $1 > $3; } 67 | expr LE expr { $$ = $1 <= $3; } 68 | expr GE expr { $$ = $1 >= $3; } 69 | expr EQ expr { $$ = $1 == $3; } 70 | expr NE expr { $$ = $1 != $3; } 71 | expr '&' expr { $$ = $1 & $3; } 72 | expr '^' expr { $$ = $1 ^ $3; } 73 | expr '|' expr { $$ = $1 | $3; } 74 | expr LAND expr { $$ = $1 && $3; } 75 | expr LOR expr { $$ = $1 || $3; } 76 | '(' expr ')' { $$ = $2; } 77 | '-' expr %prec UMINUS { $$ = -$2; } 78 | '+' expr %prec UPLUS { $$ = $2; } 79 | '!' expr { $$ = !$2; } 80 | '~' expr { $$ = ~$2; } 81 | NUMBER 82 ; 83 %% 84 85