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/*

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 * (c) 2003 Mario de Sousa

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 *

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 * Offered to the public under the terms of the GNU General Public License

     5

 * as published by the Free Software Foundation; either version 2 of the

     6

 * License, or (at your option) any later version.

     7

 *

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

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 * WITHOUT ANY WARRANTY; without even the implied warranty of

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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General

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 * Public License for more details.

    12

 *

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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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 */

    16

    17

/*

    18

 * An IEC 61131-3 IL and ST compiler.

    19

 *

    20

 * Based on the

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

    22

 *

    23

 */

    24

    25

    26

/*

    27

 * Conversion of variable declaration constructs.

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 *

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 * This is part of the 4th stage that generates

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 * a c++ source program equivalent to the IL and ST

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 * code.

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 */

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    36

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//#include <stdio.h>  /* required for NULL */

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//#include <string>

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//#include <iostream>

    40

    41

//#include "../../util/symtable.hh"

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    43

    44

    45

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class generate_c_array_initialization_c: public generate_c_typedecl_c {

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    48

  public:

    49

    typedef enum {

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      none_am,

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      dimensioncount_am,

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      initializationvalue_am,

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      arrayassignment_am,

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      varlistparse_am

    55

    } arrayinitialization_mode_t;

    56

    57

    arrayinitialization_mode_t current_mode;

    58

    59

    symbol_c* array_default_value;

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    61

  private:

    62

    int dimension_number, current_dimension, array_size;

    63

    64

  public:

    65

    generate_c_array_initialization_c(stage4out_c *s4o_ptr): generate_c_typedecl_c(s4o_ptr) {}

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    ~generate_c_array_initialization_c(void) {}

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    68

    void init_array(symbol_c *var1_list, symbol_c *array_specification, symbol_c *array_initialization) {

    69

      int i;

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    71

      dimension_number = 0;

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      current_dimension = 0;

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      array_size = 1;

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      array_default_value = NULL;

    75

    76

      current_mode = dimensioncount_am;

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      array_specification->accept(*this);

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      current_mode = initializationvalue_am;

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      s4o.print("\n");

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      s4o.print(s4o.indent_spaces + "{\n");

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      s4o.indent_right();

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      s4o.print(s4o.indent_spaces + "int index[");

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      print_integer(dimension_number);

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      s4o.print("];\n");

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      s4o.print(s4o.indent_spaces);

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      array_specification->accept(*this);

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      s4o.print(" temp = ");

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      array_initialization->accept(*this);

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      s4o.print(";\n");

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      current_mode = arrayassignment_am;

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      array_specification->accept(*this);

    94

    95

      current_mode = varlistparse_am;

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      var1_list->accept(*this);

    97

    98

      current_mode = arrayassignment_am;

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      for (i = 0; i < dimension_number; i++) {

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        s4o.indent_left();

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        s4o.print(s4o.indent_spaces + "}\n");

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      }

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      s4o.indent_left();

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      s4o.print(s4o.indent_spaces + "}");

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    }

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    void *visit(identifier_c *type_name) {

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      symbol_c *type_decl;

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      switch (current_mode) {

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        case dimensioncount_am:

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        case arrayassignment_am:

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          /* look up the type declaration... */

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          type_decl = type_symtable.find_value(type_name);

   114

          if (type_decl == type_symtable.end_value())

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            /* Type declaration not found!! */

   116

            ERROR;

   117

          type_decl->accept(*this);

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          break;

   119

        default:

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          print_token(type_name);

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          break;

   122

      }

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      return NULL;

   124

    }

   125

   126

    void *visit(var1_list_c *symbol) {

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      int i, j;

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   129

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

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        s4o.print(s4o.indent_spaces);

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        print_variable_prefix();

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        symbol->elements[i]->accept(*this);

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        for (j = 0; j < dimension_number; j++) {

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          s4o.print("[index[");

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          print_integer(j);

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          s4o.print("]]");

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        }

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        s4o.print(" = temp");

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        for (j = 0; j < dimension_number; j++) {

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          s4o.print("[index[");

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          print_integer(j);

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          s4o.print("]]");

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        }

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        s4o.print(";\n");

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      }

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      return NULL;

   147

    }

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

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/* B 1.3.3 - Derived data types */

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

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   153

    /* ARRAY '[' array_subrange_list ']' OF non_generic_type_name */

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    void *visit(array_specification_c *symbol) {

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      switch (current_mode) {

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        case dimensioncount_am:

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          symbol->array_subrange_list->accept(*this);

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          array_default_value = (symbol_c *)symbol->non_generic_type_name->accept(*type_initial_value_c::instance());;

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          break;

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        default:

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          symbol->array_subrange_list->accept(*this);

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          break;

   163

      } 

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      return NULL;

   165

    }

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    /*  signed_integer DOTDOT signed_integer */

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    //SYM_REF2(subrange_c, lower_limit, upper_limit)

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    void *visit(subrange_c *symbol) {

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      switch (current_mode) {

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        case dimensioncount_am:

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          dimension_number++;

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          array_size *= extract_integer(symbol->upper_limit) - extract_integer(symbol->lower_limit) + 1;

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          break;

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        case arrayassignment_am:

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          s4o.print(s4o.indent_spaces + "for (index[");

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          print_integer(current_dimension);

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          s4o.print("] = 0; index[");

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          print_integer(current_dimension);

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          s4o.print("] <= ");

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          print_integer(extract_integer(symbol->upper_limit) - extract_integer(symbol->lower_limit));

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          s4o.print("; index[");

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          print_integer(current_dimension);

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          s4o.print("]++) {\n");

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          s4o.indent_right();

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          current_dimension++;

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          break;

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        default:

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          break;

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      }

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      return NULL;

   192

    }

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    /* helper symbol for array_initialization */

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    /* array_initial_elements_list ',' array_initial_elements */

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    void *visit(array_initial_elements_list_c *symbol) {

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      switch (current_mode) {

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        case initializationvalue_am:

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          int i;

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          s4o.print("{");

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

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            if (i > 0)

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              s4o.print(", ");

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            symbol->elements[i]->accept(*this);

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            array_size--;

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          }

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          if (array_size > 0) {

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            if (symbol->n > 0)

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              s4o.print(", ");

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            for (i = 0; i < array_size; i++) {

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              if (i > 0)

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                s4o.print(", ");

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              array_default_value->accept(*this);

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            }

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          }

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          s4o.print("}");

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          break;

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        default:

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          break;

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      }

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      return NULL;

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    }

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    /* integer '(' [array_initial_element] ')' */

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    /* array_initial_element may be NULL ! */

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    void *visit(array_initial_elements_c *symbol) {

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      int initial_element_number;

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      switch (current_mode) {

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        case initializationvalue_am:

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          initial_element_number = extract_integer(symbol->integer);

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          for (int i = 0; i < initial_element_number; i++) {

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            if (i > 0)

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              s4o.print(", ");

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            if (symbol->array_initial_element != NULL)

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              symbol->array_initial_element->accept(*this);

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            else if (array_default_value != NULL)

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              array_default_value->accept(*this);

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          }

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          if (initial_element_number > 1)

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            array_size -= initial_element_number - 1;

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          break;

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        default:

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          break;

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      }

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      return NULL;

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    }

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};

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

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

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

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

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

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

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

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

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class generate_c_vardecl_c: protected generate_c_typedecl_c {

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  /* A Helper class to the main class... */

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  /* print a string, except the first time it is called */

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  /* used to print the separator "," before each variable

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   * declaration, except the first...

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   *

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   * Needs to be done in a seperate class because this is called

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   * from within various locations within the code.

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   */

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  class next_var_c {

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    private:

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      bool print_flag;

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      std::string str1, str2;

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      next_var_c *embedded_scope;

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   282

    public:

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      next_var_c(std::string s1, std::string s2) {

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        str1 = s1;

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        str2 = s2;

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        print_flag = false;

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        embedded_scope = NULL;

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      }

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      std::string get(void) {

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        if (NULL != embedded_scope)

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          return embedded_scope->get();

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   294

        bool old_print_flag = print_flag;

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        print_flag = true;

   296

        if (!old_print_flag)

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          return str1;

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        else

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          return str2;

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      }

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      /* Create a new next_var_c for an embedded scope.

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       * From now on, every call to get() will return the

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       * inner-most scope...!

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       */

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      void push(std::string s1, std::string s2) {

   307

        if (NULL != embedded_scope)

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          return embedded_scope->push(s1, s2);

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   310

        embedded_scope = new next_var_c(s1, s2);

   311

        if (NULL == embedded_scope)

   312

          ERROR;

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        return;

   314

      }

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   316

      /* Remove the inner-most scope... */

   317

      void pop(void) {

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        if (NULL != embedded_scope)

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          return embedded_scope->pop();

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        delete embedded_scope;

   322

        embedded_scope = NULL;

   323

      }

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  };

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  private:

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    /* used to generate the ',' separating the parameters in a function call */

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    next_var_c *nv;

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   331

  public:

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    /* the types of variables that need to be processed... */

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    static const unsigned int none_vt	  = 0x0000;

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    static const unsigned int input_vt	  = 0x0001;  // VAR_INPUT

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    static const unsigned int output_vt	  = 0x0002;  // VAR_OUTPUT

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    static const unsigned int inoutput_vt = 0x0004;  // VAR_IN_OUT

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    static const unsigned int private_vt  = 0x0008;  // VAR

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    static const unsigned int temp_vt	  = 0x0010;  // VAR_TEMP

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    static const unsigned int external_vt = 0x0020;  // VAR_EXTERNAL

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    static const unsigned int global_vt   = 0x0040;  // VAR_GLOBAL

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						     //    Globals declared inside a resource will not be declared

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						     //    unless global_vt is acompanied by resource_vt

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    static const unsigned int located_vt  = 0x0080;  // VAR <var_name> AT <location>

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    static const unsigned int program_vt  = 0x0100;  // PROGRAM (inside a configuration!)

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						     //    Programs declared inside a resource will not be declared

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						     //    unless program_vt is acompanied by resource_vt

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   348

    static const unsigned int eneno_vt  = 0x0200;  // EN/ENO declaration

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   350

    static const unsigned int resource_vt = 0x8000;  // RESOURCE (inside a configuration!)

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                                                     //    This, just of itself, will not print out any declarations!!

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						     //    It must be acompanied by either program_vt and/or global_vt

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   354

    /* How variables should be declared: as local variables or

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     * variables within a function call interface.

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     *

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     * This will define the format of the output generated

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     * by this class.

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     *

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     * finterface_vf: function interface parameters

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     *               e.g.  f(  int a, long b, real c );

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     *                         ---------------------

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     *               This class/function will produce the

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     *               underlined code of the above examples,

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     *               and no more!!

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     *

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     * localinit_vf: local declaration. Will include variable

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     *           initialisation if it is not a located variable.

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     *           e.g.

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     *                int a = 9;

   371

     *                long b = 99;

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     *                real c = 99.9;

   373

     *

   374

     * local_vf: local declaration. Will NOT include variable

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     *           initialisation.

   376

     *           e.g.

   377

     *                int a;

   378

     *                long b;

   379

     *                real c;

   380

     *

   381

     * init_vf: local initialisation without declaration.

   382

     *           e.g.

   383

     *                a = 9;

   384

     *                b = 99;

   385

     *                c = 99.9;

   386

     *

   387

     * constructorinit_vf: initialising of member variables...

   388

     *                e.g. for a constructor...

   389

     *                class_name_c(void)

   390

     *                : a(9), b(99), c(99.9)  { // code... }

   391

     *                  --------------------

   392

     *               This class/function will produce the

   393

     *               underlined code of the above examples,

   394

     *               and no more!!

   395

     *

   396

     * globalinit_vf: initialising of static c++ variables. These

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     *                variables may have been declared as static inside

   398

     *                a class, in which case the scope within which they were

   399

     *                previously delcared must be passed as the second parameter

   400

     *                to the print() function.

   401

     *

   402

     *                e.g.

   403

     *                __plc_pt_c<INT, 8*sizeof(INT)> START_P::loc = __plc_pt_c<INT, 8*sizeof(INT)>("I2");

   404

     */

   405

    typedef enum {finterface_vf,

   406

                  foutputassign_vf,

   407

                  local_vf,

   408

		              localinit_vf,

   409

		              init_vf,

   410

		              constructorinit_vf,

   411

		              globalinit_vf

   412

		             } varformat_t;

   413

   414

   415

  private:

   416

    generate_c_array_initialization_c *generate_c_array_initialization;

   417

   418

    /* variable used to store the types of variables that need to be processed... */

   419

    /* Only set in the constructor...! */

   420

    /* Will contain a set of values of generate_c_vardecl_c::XXXX_vt */

   421

    unsigned int wanted_vartype;

   422

    /* variable used to store the type of variable currently being processed... */

   423

    /* Will contain a single value of generate_c_vardecl_c::XXXX_vt */

   424

    unsigned int current_vartype;

   425

   426

    /* How variables should be declared: as local variables or

   427

     * variables within a function interface...

   428

     */

   429

    /* Only set in the constructor...! */

   430

    varformat_t wanted_varformat;

   431

   432

    /* The number of variables already declared. */

   433

    /* Used to declare 'void' in case no variables are declared in a function interface... */

   434

    int finterface_var_count;

   435

   436

    /* Current parsed resource name, for resource 

   437

     * specific global variable declaration (with #define...)*/

   438

    symbol_c *resource_name;

   439

   440

    /* Store if En and ENO parameters have been defined by user */

   441

    bool en_declared;

   442

    bool eno_declared;

   443

   444

    /* Holds the references to the type and initial value

   445

     * of the variables currently being declared.

   446

     * Please read the comment under var1_init_decl_c for further

   447

     * details...

   448

     *

   449

     * We make an effort to keep these pointers pointing to NULL

   450

     * whenever we are outside the scope of variable declaration

   451

     * (i.e. when we are traversing a part of the parse tree which

   452

     * is not part of variable declaration) in order tio try to catch

   453

     * any bugs as soon as possible.

   454

     */

   455

    symbol_c *current_var_type_symbol;

   456

    symbol_c *current_var_init_symbol;

   457

    void update_type_init(symbol_c *symbol /* a spec_init_c, subrange_spec_init_c, etc... */ ) {

   458

      this->current_var_type_symbol = spec_init_sperator_c::get_spec(symbol);

   459

      this->current_var_init_symbol = spec_init_sperator_c::get_init(symbol);

   460

      if (NULL == this->current_var_type_symbol)

   461

        ERROR;

   462

      if (NULL == this->current_var_init_symbol) {

   463

        /* We try to find the data type's default value... */

   464

        this->current_var_init_symbol = (symbol_c *)this->current_var_type_symbol->accept(*type_initial_value_c::instance());

   465

      /* Note that Function Block 'data types' do not have a default value, so we cannot abort if no default value is found! */

   466

      /*

   467

      if (NULL == this->current_var_init_symbol)

   468

        ERROR;

   469

      */

   470

      }

   471

    }

   472

   473

    void void_type_init(void) {

   474

      this->current_var_type_symbol = NULL;

   475

      this->current_var_init_symbol = NULL;

   476

    }

   477

   478

    /* Only used when wanted_varformat == globalinit_vf

   479

     * Holds a pointer to an identifier_c, which in turns contains

   480

     * the identifier of the scope within which the static member was

   481

     * declared.

   482

     */

   483

    symbol_c *globalnamespace;

   484

   485

    /* Actually produce the output where variables are declared... */

   486

    /* Note that located variables are the exception, they

   487

     * being declared in the located_var_decl_c visitor...

   488

     */

   489

    void *declare_variables(symbol_c *symbol, bool is_fb = false) {

   490

      list_c *list = dynamic_cast<list_c *>(symbol);

   491

      /* should NEVER EVER occur!! */

   492

      if (list == NULL) ERROR;

   493

   494

      /* now to produce the c equivalent... */

   495

      if ((wanted_varformat == local_vf) ||

   496

          (wanted_varformat == init_vf) ||

   497

          (wanted_varformat == localinit_vf)) {

   498

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

   499

          s4o.print(s4o.indent_spaces);

   500

          if (wanted_varformat != init_vf) {

   501

            this->current_var_type_symbol->accept(*this);

   502

            s4o.print(" ");

   503

          }

   504

          print_variable_prefix();

   505

          list->elements[i]->accept(*this);

   506

          if (wanted_varformat != local_vf) {

   507

            if (this->current_var_init_symbol != NULL) {

   508

              s4o.print(" = ");

   509

              this->current_var_init_symbol->accept(*this);

   510

            }

   511

          }

   512

          s4o.print(";\n");

   513

        }

   514

      }