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/* SPDX-License-Identifier: GPL-3.0-only */
/*
* Provide more verbose and specific error messages instead of just "syntax
* error".
*/
%define parse.error verbose
/*
* Verbose error messages may contain incorrect information if LAC (Lookahead
* Correction) is not enabled.
*/
%define parse.lac full
/* Avoid symbol clashes (lopsub might also expose yy* symbols). */
%define api.prefix {txp_yy}
/*
* Although locations are automatically enabled as soon as the grammar uses the
* special @N tokens, specifying %locations explicitly allows for more accurate
* syntax error messages.
*/
%locations
/*
* Generate a pure (reentrant) parser. With this option enabled, yylval and
* yylloc become local variables in yyparse(), and a different calling
* convention is used for yylex().
*/
%define api.pure full
/* Additional arguments to yylex(), yyparse() and yyerror() */
%param {struct txp_context *ctx}
%param {struct txp_ast_node **ast}
%param {txp_yyscan_t yyscanner} /* reentrant lexers */
%{
#include "tf.h"
#include "txp.bison.h"
int yylex(TXP_YYSTYPE *lvalp, TXP_YYLTYPE *llocp, struct txp_context *ctx,
struct txp_ast_node **ast, txp_yyscan_t yyscanner);
static void yyerror(YYLTYPE *llocp, struct txp_context *ctx,
struct txp_ast_node **ast, txp_yyscan_t yyscanner, const char *msg);
%}
%union {
struct txp_ast_node *node;
}
/* terminals */
%token <node> NUM
%token <node> STRING_LITERAL
%token <node> REGEX_PATTERN
/* keywords with semantic value */
%token <node> LEN
%token <node> FALSE TRUE
%token <node> TEXT
/* keywords without semantic value */
%token TAG
/* operators, ordered by precendence */
%left OR
%left AND
%left EQUAL NOT_EQUAL
%left LESS_THAN LESS_OR_EQUAL GREATER_OR_EQUAL REGEX_MATCH FILENAME_MATCH
%left '-' '+'
%left '*' '/'
%right NOT NEG /* negation (unary minus) */
/* nonterminals */
%type <node> string
%type <node> exp
%type <node> boolexp
%%
program:
/* empty */ {*ast = NULL; return 0;}
| string {*ast = $1; return 0;}
| exp {*ast = $1; return 0;}
| boolexp {*ast = $1; return 0;}
string: STRING_LITERAL {$$ = $1;}
| TEXT {$$ = txp_new_ast_leaf_node(TEXT);}
;
exp: NUM {$$ = $1;}
| exp '+' exp {$$ = ast_node_new_binary('+', $1, $3);}
| exp '-' exp {$$ = ast_node_new_binary('-', $1, $3);}
| exp '*' exp {$$ = ast_node_new_binary('*', $1, $3);}
| exp '/' exp {$$ = ast_node_new_binary('/', $1, $3);}
| '-' exp %prec NEG {$$ = ast_node_new_unary(NEG, $2);}
| '(' exp ')' {$$ = $2;}
| LEN {$$ = txp_new_ast_leaf_node(LEN);}
;
boolexp: TAG '(' STRING_LITERAL ')' {$$ = ast_node_new_unary(TAG, $3);}
| TRUE {$$ = txp_new_ast_leaf_node(TRUE);}
| FALSE {$$ = txp_new_ast_leaf_node(FALSE);}
| '(' boolexp ')' {$$ = $2;}
| boolexp OR boolexp {$$ = ast_node_new_binary(OR, $1, $3);}
| boolexp AND boolexp {$$ = ast_node_new_binary(AND, $1, $3);}
| NOT boolexp {$$ = ast_node_new_unary(NOT, $2);}
| exp EQUAL exp {$$ = ast_node_new_binary(EQUAL, $1, $3);}
| exp NOT_EQUAL exp {$$ = ast_node_new_binary(NOT_EQUAL, $1, $3);}
| exp '<' exp {$$ = ast_node_new_binary('<', $1, $3);}
| exp '>' exp {$$ = ast_node_new_binary('>', $1, $3);}
| exp LESS_OR_EQUAL exp {
$$ = ast_node_new_binary(LESS_OR_EQUAL, $1, $3);
}
| exp GREATER_OR_EQUAL exp {
$$ = ast_node_new_binary(GREATER_OR_EQUAL, $1, $3);
}
| string REGEX_MATCH REGEX_PATTERN {
$$ = ast_node_new_binary(REGEX_MATCH, $1, $3);
}
| string EQUAL string {$$ = ast_node_new_binary(EQUAL, $1, $3);}
| string NOT_EQUAL string {$$ = ast_node_new_binary(NOT_EQUAL, $1, $3);}
;
%%
/* Called by yyparse() on error */
static void yyerror(YYLTYPE *llocp, struct txp_context *ctx,
__attribute__ ((unused)) struct txp_ast_node **ast,
__attribute__ ((unused)) txp_yyscan_t yyscanner,
const char *msg)
{
txp_parse_error(llocp->first_line, ctx, "%s", msg);
}
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