diff options
Diffstat (limited to 'edify/parser.y')
-rw-r--r-- | edify/parser.y | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/edify/parser.y b/edify/parser.y new file mode 100644 index 000000000..67a210fca --- /dev/null +++ b/edify/parser.y @@ -0,0 +1,121 @@ +%{ +/* + * Copyright (C) 2009 The Android Open Source Project + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "expr.h" +#include "parser.h" + +extern int gLine; +extern int gColumn; + +void yyerror(Expr** root, const char* s); +int yyparse(Expr** root); + +%} + +%union { + char* str; + Expr* expr; + struct { + int argc; + Expr** argv; + } args; +} + +%token AND OR SUBSTR SUPERSTR EQ NE IF THEN ELSE ENDIF +%token <str> STRING BAD +%type <expr> expr +%type <args> arglist + +%parse-param {Expr** root} +%error-verbose + +/* declarations in increasing order of precedence */ +%left ';' +%left ',' +%left OR +%left AND +%left EQ NE +%left '+' +%right '!' + +%% + +input: expr { *root = $1; } +; + +expr: STRING { + $$ = malloc(sizeof(Expr)); + $$->fn = Literal; + $$->name = $1; + $$->argc = 0; + $$->argv = NULL; +} +| '(' expr ')' { $$ = $2; } +| expr ';' { $$ = $1; } +| expr ';' expr { $$ = Build(SequenceFn, 2, $1, $3); } +| error ';' expr { $$ = $3; } +| expr '+' expr { $$ = Build(ConcatFn, 2, $1, $3); } +| expr EQ expr { $$ = Build(EqualityFn, 2, $1, $3); } +| expr NE expr { $$ = Build(InequalityFn, 2, $1, $3); } +| expr AND expr { $$ = Build(LogicalAndFn, 2, $1, $3); } +| expr OR expr { $$ = Build(LogicalOrFn, 2, $1, $3); } +| '!' expr { $$ = Build(LogicalNotFn, 1, $2); } +| IF expr THEN expr ENDIF { $$ = Build(IfElseFn, 2, $2, $4); } +| IF expr THEN expr ELSE expr ENDIF { $$ = Build(IfElseFn, 3, $2, $4, $6); } +| STRING '(' arglist ')' { + $$ = malloc(sizeof(Expr)); + $$->fn = FindFunction($1); + if ($$->fn == NULL) { + char buffer[256]; + snprintf(buffer, sizeof(buffer), "unknown function \"%s\"", $1); + yyerror(root, buffer); + YYERROR; + } + $$->name = $1; + $$->argc = $3.argc; + $$->argv = $3.argv; +} +; + +arglist: /* empty */ { + $$.argc = 0; + $$.argv = NULL; +} +| expr { + $$.argc = 1; + $$.argv = malloc(sizeof(Expr*)); + $$.argv[0] = $1; +} +| arglist ',' expr { + $$.argc = $1.argc + 1; + $$.argv = realloc($$.argv, $$.argc * sizeof(Expr*)); + $$.argv[$$.argc-1] = $3; +} +; + +%% + +void yyerror(Expr** root, const char* s) { + if (strlen(s) == 0) { + s = "syntax error"; + } + printf("line %d col %d: %s\n", gLine, gColumn, s); +} |