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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

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

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 * License, or (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, 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.

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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 IL and ST 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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/*

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 * Seperation of type specification and default value constructs

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 * (for e.g. simple_spec_init_c), into a type specificiation part,

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 * and a default value part.

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 */

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

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//#include <string>

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//#include <iostream>

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

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class spec_init_sperator_c: public null_visitor_c {

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  private:

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    /* this is a singleton class... */

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    static spec_init_sperator_c *class_instance;

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    static spec_init_sperator_c *get_class_instance(void) {

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      if (NULL == class_instance)

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        class_instance = new spec_init_sperator_c();

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      if (NULL == class_instance)

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        ERROR;

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      return class_instance;

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    }

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  private:

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    typedef enum {search_spec, search_init} search_what_t;

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    static search_what_t search_what;

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  public:

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    /* the only two public functions... */

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    static symbol_c *get_spec(symbol_c *spec_init) {

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      search_what = search_spec;

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      return (symbol_c *)spec_init->accept(*get_class_instance());

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    }

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    static symbol_c *get_init(symbol_c *spec_init) {

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      search_what = search_init;

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      return (symbol_c *)spec_init->accept(*get_class_instance());

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    }

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//  private:

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  public:  /* probably needs to be public so it may be visited... !! */

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

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/* B 1.1 - Letters, digits and identifiers */

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

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// SYM_TOKEN(identifier_c)

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void *visit(identifier_c *symbol) {

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  TRACE("spec_init_sperator_c::identifier_c");

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  switch (search_what) {

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    /* if we ever get called sith a simple identifier_c, then it must be a previously declared type... */

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    case search_spec: return symbol;

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    case search_init: return NULL;

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  }

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  ERROR; /* should never occur */

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  return NULL;

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}

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

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/* B 1.3.3 - Derived data types */

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

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/* simple_specification ASSIGN constant */

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void *visit(simple_spec_init_c *symbol) {

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  TRACE("spec_init_sperator_c::simple_spec_init_c");

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  switch (search_what) {

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    case search_spec: return symbol->simple_specification;

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    case search_init: return symbol->constant;

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  }

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  ERROR; /* should never occur */

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  return NULL;

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}

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/* subrange_specification ASSIGN signed_integer */

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void *visit(subrange_spec_init_c *symbol) {

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  TRACE("spec_init_sperator_c::subrange_spec_init_c");

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  switch (search_what) {

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    case search_spec: return symbol->subrange_specification;

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    case search_init: return symbol->signed_integer;

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  }

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  ERROR; /* should never occur */

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  return NULL;

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}

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/* enumerated_specification ASSIGN enumerated_value */

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void *visit(enumerated_spec_init_c *symbol) {

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  TRACE("spec_init_sperator_c::enumerated_spec_init_c");

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  switch (search_what) {

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    case search_spec: return symbol->enumerated_specification;

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    case search_init: return symbol->enumerated_value;

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  }

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  ERROR; /* should never occur */

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  return NULL;

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}

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/* structure_type_name ASSIGN structure_initialization */

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/* structure_initialization may be NULL ! */

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//SYM_REF2(initialized_structure_c, structure_type_name, structure_initialization)

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void *visit(initialized_structure_c *symbol) {

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  TRACE("spec_init_sperator_c::initialized_structure_c");

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  switch (search_what) {

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    case search_spec: return symbol->structure_type_name;

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    case search_init: return symbol->structure_initialization;

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  }

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  ERROR; /* should never occur */

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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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/* fb_name_list ':' function_block_type_name ASSIGN structure_initialization */

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/* structure_initialization -> may be NULL ! */

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void *visit(fb_name_decl_c *symbol) {

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  TRACE("spec_init_sperator_c::fb_name_decl_c");

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  switch (search_what) {

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    case search_spec: return symbol->function_block_type_name;

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    case search_init: return symbol->structure_initialization;

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  }

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  ERROR; /* should never occur */

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  return NULL;

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}

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};   /* class spec_init_sperator_c */

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spec_init_sperator_c *spec_init_sperator_c ::class_instance = NULL;

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spec_init_sperator_c::search_what_t spec_init_sperator_c::search_what;