postgresql/contrib/pgbench/exprparse.y

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%{
/*-------------------------------------------------------------------------
*
* exprparse.y
* bison grammar for a simple expression syntax
*
* Portions Copyright (c) 1996-2014, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*-------------------------------------------------------------------------
*/
#include "postgres_fe.h"
#include "pgbench.h"
PgBenchExpr *expr_parse_result;
static PgBenchExpr *make_integer_constant(int64 ival);
static PgBenchExpr *make_variable(char *varname);
static PgBenchExpr *make_op(char operator, PgBenchExpr *lexpr,
PgBenchExpr *rexpr);
%}
%expect 0
%name-prefix="expr_yy"
%union
{
int64 ival;
char *str;
PgBenchExpr *expr;
}
%type <expr> expr
%type <ival> INTEGER
%type <str> VARIABLE
%token INTEGER VARIABLE
%token CHAR_ERROR /* never used, will raise a syntax error */
%left '+' '-'
%left '*' '/' '%'
%right UMINUS
%%
result: expr { expr_parse_result = $1; }
expr: '(' expr ')' { $$ = $2; }
| '+' expr %prec UMINUS { $$ = $2; }
| '-' expr %prec UMINUS { $$ = make_op('-', make_integer_constant(0), $2); }
| expr '+' expr { $$ = make_op('+', $1, $3); }
| expr '-' expr { $$ = make_op('-', $1, $3); }
| expr '*' expr { $$ = make_op('*', $1, $3); }
| expr '/' expr { $$ = make_op('/', $1, $3); }
| expr '%' expr { $$ = make_op('%', $1, $3); }
| INTEGER { $$ = make_integer_constant($1); }
| VARIABLE { $$ = make_variable($1); }
;
%%
static PgBenchExpr *
make_integer_constant(int64 ival)
{
PgBenchExpr *expr = pg_malloc(sizeof(PgBenchExpr));
expr->etype = ENODE_INTEGER_CONSTANT;
expr->u.integer_constant.ival = ival;
return expr;
}
static PgBenchExpr *
make_variable(char *varname)
{
PgBenchExpr *expr = pg_malloc(sizeof(PgBenchExpr));
expr->etype = ENODE_VARIABLE;
expr->u.variable.varname = varname;
return expr;
}
static PgBenchExpr *
make_op(char operator, PgBenchExpr *lexpr, PgBenchExpr *rexpr)
{
PgBenchExpr *expr = pg_malloc(sizeof(PgBenchExpr));
expr->etype = ENODE_OPERATOR;
expr->u.operator.operator = operator;
expr->u.operator.lexpr = lexpr;
expr->u.operator.rexpr = rexpr;
return expr;
}
#include "exprscan.c"