diff -r 9317e04c1dde -r b22ae67d8003 absyntax_utils/get_var_name.cc --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/absyntax_utils/get_var_name.cc Mon Apr 16 15:10:31 2012 +0100 @@ -0,0 +1,120 @@ +/* + * matiec - a compiler for the programming languages defined in IEC 61131-3 + * + * Copyright (C) 2012 Mario de Sousa (msousa@fe.up.pt) + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + * + * + * This code is made available on the understanding that it will not be + * used in safety-critical situations without a full and competent review. + */ + +/* + * An IEC 61131-3 compiler. + * + * Based on the + * FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10) + * + */ + +/* + * A small helper visitor class, that will + * return the name (tokn_c *) of a variable, as it will + * appear in the variable declaration. + */ + +/* For ex.: + * VAR + * A : int; + * B : ARRAY [1..9] of int; + * C : some_struct_t; + * END_VAR + * + * A := 56; + * B[8] := 99; + * C.e := 77; + * + * Calling this visitor class with symbolic_variable_c instance referencing 'A' in + * the line 'A := 56', will return the string "A". + * + * Calling this visitor class with array_variable_c instance referencing 'B[8]' in + * the line 'B[8] := 99', will return the string "B". + * + * Calling this visitor class with array_variable_c instance referencing 'C.e' in + * the line 'C.e := 77', will return the string "C". + */ + + +#include "absyntax_utils.hh" + + + + + + +get_var_name_c *get_var_name_c::singleton_instance_ = NULL; + + + + +token_c *get_var_name_c::get_name(symbol_c *symbol) { + if (NULL == singleton_instance_) singleton_instance_ = new get_var_name_c(); + if (NULL == singleton_instance_) ERROR; + + return (token_c *)(symbol->accept(*singleton_instance_)); +} + + +/*************************/ +/* B.1 - Common elements */ +/*************************/ +/*******************************************/ +/* B 1.1 - Letters, digits and identifiers */ +/*******************************************/ +// SYM_TOKEN(identifier_c) +void *get_var_name_c::visit(identifier_c *symbol) {return (void *)symbol;} + +/*********************/ +/* B 1.4 - Variables */ +/*********************/ +// SYM_REF2(symbolic_variable_c, var_name, unused) +void *get_var_name_c::visit(symbolic_variable_c *symbol) {return symbol->var_name->accept(*this);} + +/********************************************/ +/* B.1.4.1 Directly Represented Variables */ +/********************************************/ +// SYM_TOKEN(direct_variable_c) + +/*************************************/ +/* B.1.4.2 Multi-element Variables */ +/*************************************/ +/* subscripted_variable '[' subscript_list ']' */ +// SYM_REF2(array_variable_c, subscripted_variable, subscript_list) +void *get_var_name_c::visit(array_variable_c *symbol) {return symbol->subscripted_variable->accept(*this);} + +/* subscript_list ',' subscript */ +// SYM_LIST(subscript_list_c) + +/* record_variable '.' field_selector */ +/* WARNING: input and/or output variables of function blocks + * may be accessed as fields of a tructured variable! + * Code handling a structured_variable_c must take + * this into account! + */ +// SYM_REF2(structured_variable_c, record_variable, field_selector) +void *get_var_name_c::visit(structured_variable_c *symbol) {return symbol->record_variable->accept(*this);} + + +