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/*

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 *  matiec - a compiler for the programming languages defined in IEC 61131-3

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 *

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 *  Copyright (C) 2003-2011  Mario de Sousa (msousa@fe.up.pt)

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 *  Copyright (C) 2007-2011  Laurent Bessard and Edouard Tisserant

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 *

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 *  This program is free software: you can redistribute it and/or modify

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 *  it under the terms of the GNU General Public License as published by

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 *  the Free Software Foundation, either version 3 of the License, or

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 *  (at your option) any later version.

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 *

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 *  This program is distributed in the hope that it will be useful,

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 *  but WITHOUT ANY WARRANTY; without even the implied warranty of

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 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

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 *  GNU General Public License for more details.

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 *

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 *  You should have received a copy of the GNU General Public License

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 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.

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 *

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 *

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 * This code is made available on the understanding that it will not be

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 * used in safety-critical situations without a full and competent review.

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 */

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/*

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 * An IEC 61131-3 compiler.

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 *

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 * Based on the

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 * FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)

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 *

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 */

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#include "absyntax_utils.hh"

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/* Returns the function block type declaration

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 * of a specific function block instance.

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 */

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/* Returns the type name of a specific function block

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 * instance. This class will search the variable

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 * declarations inside the scope given to it

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 * searching for the declaration of the function

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 * block instance.

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 *

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 * The class constructor must be given the search scope

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 * (function, function block or program within which

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 * the function block instance was declared).

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 *

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 * This class will search the tree from the root given to the

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 * constructor. Another option would be to build a symbol table,

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 * and search that instead. Building the symbol table would be done

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 * while visiting the variable declaration objects in the parse

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 * tree. Unfortuantely, generate_c_c does not visit these

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 * objects, delegating it to another class. This means that

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 * we would need another specialised class just to build the

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 * symbol table. We might just as well have a specialised class

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 * that searches the tree itself for the relevant info. This

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 * class is exactly that...!

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 */

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search_fb_instance_decl_c::search_fb_instance_decl_c(symbol_c *search_scope) {

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  this->search_scope = search_scope;

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  this->current_fb_type_name = NULL;

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}

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symbol_c *search_fb_instance_decl_c::get_type_name(symbol_c *fb_instance_name) {

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  this->search_name = fb_instance_name;

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  return (symbol_c *)search_scope->accept(*this);

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}

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/***************************/

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/* B 0 - Programming Model */

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/***************************/

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void *search_fb_instance_decl_c::visit(library_c *symbol) {

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  /* we do not want to search multiple declaration scopes,

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   * so we do not visit all the functions, fucntion blocks, etc...

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   */

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  return NULL;

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}

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/******************************************/

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/* B 1.4.3 - Declaration & Initialisation */

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/******************************************/

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/* name_list ':' function_block_type_name ASSIGN structure_initialization */

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/* structure_initialization -> may be NULL ! */

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void *search_fb_instance_decl_c::visit(fb_name_decl_c *symbol) {

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  current_fb_type_name = symbol->function_block_type_name;

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  return symbol->fb_name_list->accept(*this);

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}

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/* name_list ',' fb_name */

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void *search_fb_instance_decl_c::visit(fb_name_list_c *symbol) {

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  list_c *list = symbol;

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  for(int i = 0; i < list->n; i++) {

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    if (compare_identifiers(list->elements[i], search_name) == 0)

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  /* by now, current_fb_declaration should be != NULL */

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      return current_fb_type_name;

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  }

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  return NULL;

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}

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/* name_list ',' fb_name */

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void *search_fb_instance_decl_c::visit(external_declaration_c *symbol) {

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  if (compare_identifiers(symbol->global_var_name, search_name) == 0)

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	return symbol->specification;

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  return NULL;

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}

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/**************************************/

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/* B.1.5 - Program organization units */

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/**************************************/

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/***********************/

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/* B 1.5.1 - Functions */

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/***********************/

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void *search_fb_instance_decl_c::visit(function_declaration_c *symbol) {

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  /* no need to search through all the body, so we only

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   * visit the variable declarations...!

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   */

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  return symbol->var_declarations_list->accept(*this);

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}

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/*****************************/

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/* B 1.5.2 - Function Blocks */

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/*****************************/

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void *search_fb_instance_decl_c::visit(function_block_declaration_c *symbol) {

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  /* no need to search through all the body, so we only

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   * visit the variable declarations...!

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   */

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  return symbol->var_declarations->accept(*this);

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}

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/**********************/

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/* B 1.5.3 - Programs */

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/**********************/

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void *search_fb_instance_decl_c::visit(program_declaration_c *symbol) {

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  /* no need to search through all the body, so we only

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   * visit the variable declarations...!

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   */

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  return symbol->var_declarations->accept(*this);

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}