absyntax_utils/search_fb_instance_decl.hh
author mjsousa
Sat, 07 May 2016 21:17:49 +0100
changeset 1010 242907849850
parent 706 31553c22f318
permissions -rwxr-xr-x
Correctly identify errors when parsing erroneous code (make sure flex goes back to INITIAL state when code contains errors that do not allow determining whether ST or IL is being parsed)
/*
 *  matiec - a compiler for the programming languages defined in IEC 61131-3
 *
 *  Copyright (C) 2003-2011  Mario de Sousa (msousa@fe.up.pt)
 *  Copyright (C) 2007-2011  Laurent Bessard and Edouard Tisserant
 *
 *  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 <http://www.gnu.org/licenses/>.
 *
 *
 * 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)
 *
 */



/* Returns the function block type declaration
 * of a specific function block instance.
 */



/* Returns the type name of a specific function block
 * instance. This class will search the variable
 * declarations inside the scope given to it
 * searching for the declaration of the function
 * block instance.
 *
 * The class constructor must be given the search scope
 * (function, function block or program within which
 * the function block instance was declared).
 *
 * This class will search the tree from the root given to the
 * constructor. Another option would be to build a symbol table,
 * and search that instead. Building the symbol table would be done
 * while visiting the variable declaration objects in the parse
 * tree. Unfortuantely, generate_c_c does not visit these
 * objects, delegating it to another class. This means that
 * we would need another specialised class just to build the
 * symbol table. We might just as well have a specialised class
 * that searches the tree itself for the relevant info. This
 * class is exactly that...!
 */


class search_fb_instance_decl_c: public search_visitor_c {

  private:
    symbol_c *search_scope;

    symbol_c *search_name;
    symbol_c *current_fb_type_name;

  public:
    search_fb_instance_decl_c(symbol_c *search_scope);
    symbol_c *get_type_name(symbol_c *fb_instance_name);

  public:
  /***************************/
  /* B 0 - Programming Model */
  /***************************/
    void *visit(library_c *symbol);

  /******************************************/
  /* B 1.4.3 - Declaration & Initialisation */
  /******************************************/
  
  /* name_list ':' function_block_type_name ASSIGN structure_initialization */
  /* structure_initialization -> may be NULL ! */
    void *visit(fb_name_decl_c *symbol);
  /* name_list ',' fb_name */
    void *visit(fb_name_list_c *symbol);
  /*  global_var_name ':' (simple_specification|subrange_specification|enumerated_specification|array_specification|prev_declared_structure_type_name|function_block_type_name */
    void *visit(external_declaration_c *symbol);


  /**************************************/
  /* B.1.5 - Program organization units */
  /**************************************/
  /***********************/
  /* B 1.5.1 - Functions */
  /***********************/
    void *visit(function_declaration_c *symbol);

  /*****************************/
  /* B 1.5.2 - Function Blocks */
  /*****************************/
    void *visit(function_block_declaration_c *symbol);

  /**********************/
  /* B 1.5.3 - Programs */
  /**********************/
    void *visit(program_declaration_c *symbol);
}; // search_fb_instance_decl_c