1

/*

     2

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

     3

 *

     4

 *  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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 *

    17

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

    18

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

    19

 *

    20

 *

    21

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

    22

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

    23

 */

    24

    25

/*

    26

 * An IEC 61131-3 compiler.

    27

 *

    28

 * 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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 */

    32

    33

/*

    34

 * Function call parameter iterator.

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 * It will iterate through the non-formal parameters of a function call

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 * (i.e. function calls using the foo(<param1>, <param2>, ...) syntax).

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 * and/or search through the formal parameters of a function call

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 * (i.e. function calls using the foo(<name1> = <param1>, <name2> = <param2>, ...) syntax).

    39

 *

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 * Calls to function blocks and programs are also supported.

    41

 *

    42

 * Note that calls to next_nf() will only iterate through non-formal parameters,

    43

 * calls to next_f() will only iterate through formal parameters,

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 * and calls to search_f() will only serach through formal parameters.

    45

 */

    46

    47

    48

    49

#include "function_call_param_iterator.hh"

    50

#include <strings.h>

    51

    52

    53

//#define DEBUG

    54

#ifdef DEBUG

    55

#define TRACE(classname) printf("\n____%s____\n",classname);

    56

#else

    57

#define TRACE(classname)

    58

#endif

    59

    60

#define ERROR error_exit(__FILE__,__LINE__)

    61

/* function defined in main.cc */

    62

extern void error_exit(const char *file_name, int line_no);

    63

    64

    65

    66

    67

    68

void *function_call_param_iterator_c::search_list(list_c *list) {

    69

  switch (current_operation) {

    70

    case iterate_nf_op:

    71

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

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

    73

        if (NULL != res) {

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          /* It went through the handle_parameter_assignment() function,

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           * and is therefore a parameter assignment (<param> = <value>),

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           * and not a simple expression (<value>).

    77

           */

    78

          /* we do nothing... */

    79

        } else {

    80

          param_count++;

    81

          if (param_count == iterate_nf_next_param) {

    82

            return list->elements[i];

    83

          }

    84

        }

    85

      }

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      return NULL;

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      break;

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    89

    case iterate_f_op:

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

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

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        if (NULL != res) {

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          /* It went through the handle_parameter_assignment() function,

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           * and is therefore a parameter assignment (<param> = <value>),

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           * and not a simple expression (<value>).

    96

           */

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          param_count++;

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          if (param_count == iterate_f_next_param) {

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            return res;

   100

          }

   101

        } else {

   102

          /* we do nothing... */

   103

        }

   104

      }

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      return NULL;

   106

      break;

   107

   108

    case search_f_op:

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

   110

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

   111

        if (res != NULL)

   112

          return res;

   113

      }

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      return NULL;

   115

      break;

   116

  } /* switch */

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  return NULL;

   118

}

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   120

   121

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void *function_call_param_iterator_c::handle_parameter_assignment(symbol_c *variable_name, symbol_c *expression) {

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  switch (current_operation) {

   124

    case iterate_nf_op:

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          /* UGLY HACK -> this will be detected in the search_list() function */

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      return (void *)variable_name; /* anything, as long as it is not NULL!! */

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      break;

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   129

    case iterate_f_op:

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      current_value = expression;

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      return (void *)variable_name;

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      break;

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   134

    case search_f_op:

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      identifier_c *variable_name2 = dynamic_cast<identifier_c *>(variable_name);

   136

   137

      if (variable_name2 == NULL) ERROR;

   138

   139

      if (strcasecmp(search_param_name->value, variable_name2->value) == 0)

   140

        /* FOUND! This is the same parameter!! */

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        return (void *)expression;

   142

      return NULL;

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      break;

   144

  }

   145

   146

  ERROR;

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  return NULL;

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}

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   150

   151

/* start off at the first parameter once again... */

   152

void function_call_param_iterator_c::reset(void) {

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  iterate_nf_next_param = 0;

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  iterate_f_next_param  = 0;

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  param_count = 0;

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}

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/* initialise the iterator object.

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 * We must be given a reference to the function/program/function block call

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 * that will be analysed...

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 */

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function_call_param_iterator_c::function_call_param_iterator_c(symbol_c *f_call) {

   163

  /* It is expected that f_call will reference one of the following:

   164

   *  program_configuration_c

   165

   *  function_invocation_c

   166

   *  fb_invocation_c

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   *  il_function_call_c

   168

   *  il_formal_funct_call_c

   169

   *  ... (have I missed any?)

   170

   */

   171

  this->f_call = f_call;

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  search_param_name = NULL;

   173

  reset();

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}

   175

   176

/* Skip to the next formal parameter. After object creation,

   177

 * the object references on parameter _before_ the first, so

   178

 * this function must be called once to get the object to

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 * reference the first parameter...

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 *

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 * Returns the paramater name to which a value is being passed!

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 * You can determine the value being passed by calling 

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 * function_call_param_iterator_c::search_f()

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 */

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symbol_c *function_call_param_iterator_c::next_f(void) {

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  current_value = NULL;

   187

  param_count = 0;

   188

  iterate_f_next_param++;

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  current_operation = function_call_param_iterator_c::iterate_f_op;

   190

  void *res = f_call->accept(*this);

   191

  return (symbol_c *)res;

   192

}

   193

   194

   195

/* Skip to the next non-formal parameter. After object creation,

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 * the object references on parameter _before_ the first, so

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 * this function must be called once to get the object to

   198

 * reference the first parameter...

   199

 *

   200

 * Returns whatever is being passed to the parameter!

   201

 */

   202

symbol_c *function_call_param_iterator_c::next_nf(void) {

   203

  current_value = NULL;

   204

  param_count = 0;

   205

  iterate_nf_next_param++;

   206

  current_operation = function_call_param_iterator_c::iterate_nf_op;

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  void *res = f_call->accept(*this);

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  current_value = (symbol_c *)res;

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  return (symbol_c *)res;

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}

   211

   212

/* Search for the value passed to the parameter named <param_name>...  */

   213

symbol_c *function_call_param_iterator_c::search_f(symbol_c *param_name) {

   214

  current_value = NULL;

   215

  if (NULL == param_name) ERROR;

   216

  search_param_name = dynamic_cast<identifier_c *>(param_name);

   217

  if (NULL == search_param_name) ERROR;

   218

  current_operation = function_call_param_iterator_c::search_f_op;

   219

  void *res = f_call->accept(*this);

   220

  current_value = (symbol_c *)res;

   221

  return (symbol_c *)res;

   222

}

   223

   231

/* Returns the value being passed to the current parameter. */

   232

symbol_c *function_call_param_iterator_c::get_current_value(void) {

   233

  return current_value;

   234

}

   235

   236

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

   237

/* B 1.7 Configuration elements */

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

   239

   240

/*

   241

CONFIGURATION configuration_name

   242

   optional_global_var_declarations

   243

   (resource_declaration_list | single_resource_declaration)

   244

   optional_access_declarations

   245

   optional_instance_specific_initializations

   246

END_CONFIGURATION

   247

*/

   248

/*

   249

SYM_REF6(configuration_declaration_c, configuration_name, global_var_declarations, resource_declarations, access_declarations, instance_specific_initializations, unused)

   250

*/

   251

   252

/* helper symbol for configuration_declaration */

   253

/*

   254

SYM_LIST(resource_declaration_list_c)

   255

*/

   256

   257

/*

   258

RESOURCE resource_name ON resource_type_name

   259

   optional_global_var_declarations

   260

   single_resource_declaration

   261

END_RESOURCE

   262

*/

   263

/*

   264

SYM_REF4(resource_declaration_c, resource_name, resource_type_name, global_var_declarations, resource_declaration)

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*/

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   267

/* task_configuration_list program_configuration_list */

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/*

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SYM_REF2(single_resource_declaration_c, task_configuration_list, program_configuration_list)

   270

*/

   271

   272

/* helper symbol for single_resource_declaration */

   273

/*

   274

SYM_LIST(task_configuration_list_c)

   275

*/

   276

   277

/* helper symbol for single_resource_declaration */

   278

/*

   279

SYM_LIST(program_configuration_list_c)

   280

*/

   281

   282

/* helper symbol for

   283

 *  - access_path

   284

 *  - instance_specific_init

   285

 */

   286

/*

   287

SYM_LIST(any_fb_name_list_c)

   288

*/

   289

   290

/*  [resource_name '.'] global_var_name ['.' structure_element_name] */

   291

/*

   292

SYM_REF4(global_var_reference_c, resource_name, global_var_name, structure_element_name, unused)

   293

*/

   294

   295

/*  prev_declared_program_name '.' symbolic_variable */

   296

/*

   297

SYM_REF2(program_output_reference_c, program_name, symbolic_variable)

   298

*/

   299

   300

/*  TASK task_name task_initialization */

   301

/*

   302

SYM_REF2(task_configuration_c, task_name, task_initialization)

   303

*/

   304

   305

/*  '(' [SINGLE ASSIGN data_source ','] [INTERVAL ASSIGN data_source ','] PRIORITY ASSIGN integer ')' */

   306

/*

   307

SYM_REF4(task_initialization_c, single_data_source, interval_data_source, priority_data_source, unused)

   308

*/

   309

   310

/*  PROGRAM [RETAIN | NON_RETAIN] program_name [WITH task_name] ':' program_type_name ['(' prog_conf_elements ')'] */

   311

// SYM_REF6(program_configuration_c, retain_option, program_name, task_name, program_type_name, prog_conf_elements, unused)

   312

void *function_call_param_iterator_c::visit(program_configuration_c *symbol) {

   313

  TRACE("program_configuration_c");

   314

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

   315

}

   316

   317

/* prog_conf_elements ',' prog_conf_element */

   318

// SYM_LIST(prog_conf_elements_c)

   319

void *function_call_param_iterator_c::visit(prog_conf_elements_c *symbol) {

   320

  TRACE("prog_conf_elements_c");

   321

  return search_list(symbol);

   322

}

   323

   324

/*  fb_name WITH task_name */

   325

/*

   326

SYM_REF2(fb_task_c, fb_name, task_name)

   327

*/

   328

   329

/*  any_symbolic_variable ASSIGN prog_data_source */

   330

// SYM_REF2(prog_cnxn_assign_c, symbolic_variable, prog_data_source)

   331

void *function_call_param_iterator_c::visit(prog_cnxn_assign_c *symbol) {

   332

  TRACE("prog_cnxn_assign_c");

   333

   334

  /* NOTE: symbolic_variable may be something other than a symbolic_variable_c, but I (Mario)

   335

   *       do not understand the semantics that should be implmeneted if it is not a

   336

   *        symbolic_variable, so for the moment we simply give up!

   337

   */

   338

  symbolic_variable_c *symb_var = dynamic_cast<symbolic_variable_c *>(symbol->symbolic_variable);

   339

  if (NULL == symb_var)

   340

    ERROR;

   341

   342

  return handle_parameter_assignment(symb_var->var_name, symbol->prog_data_source);

   343

}

   344

   345

/* any_symbolic_variable SENDTO data_sink */

   346

// SYM_REF2(prog_cnxn_sendto_c, symbolic_variable, prog_data_source)

   347

void *function_call_param_iterator_c::visit(prog_cnxn_sendto_c *symbol) {

   348

  TRACE("prog_cnxn_sendto_c");

   349

   350

  /* NOTE: symbolic_variable may be something other than a symbolic_variable_c, but I (Mario)

   351

   *       do not understand the semantics that should be implmeneted if it is not a

   352

   *        symbolic_variable, so for the moment we simply give up!

   353

   */

   354

  symbolic_variable_c *symb_var = dynamic_cast<symbolic_variable_c *>(symbol->symbolic_variable);

   355

  if (NULL == symb_var)

   356

    ERROR;

   357

   358

  return handle_parameter_assignment(symb_var->var_name, symbol->data_sink);

   359

}

   360

   361

/* VAR_CONFIG instance_specific_init_list END_VAR */

   362

/*

   363

SYM_REF2(instance_specific_initializations_c, instance_specific_init_list, unused)

   364

*/

   365

   366

/* helper symbol for instance_specific_initializations */

   367

/*

   368

SYM_LIST(instance_specific_init_list_c)

   369

*/

   370

   371

/* resource_name '.' program_name '.' {fb_name '.'}

   372

    ((variable_name [location] ':' located_var_spec_init) | (fb_name ':' fb_initialization))

   373

*/

   374

/*

   375

SYM_REF6(instance_specific_init_c, resource_name, program_name, any_fb_name_list, variable_name, location, initialization)

   376

*/

   377

   378

/* helper symbol for instance_specific_init */

   379

/* function_block_type_name ':=' structure_initialization */

   380

/*

   381

SYM_REF2(fb_initialization_c, function_block_type_name, structure_initialization)

   382

*/

   383

   384

   385

   386

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

   387

/* B.2 - Language IL (Instruction List) */

   388

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

   389

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

   390

/* B 2.1 Instructions and Operands */

   391

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

   392

   393

/* | function_name [il_operand_list] */

   394

// SYM_REF2(il_function_call_c, function_name, il_operand_list)

   395

void *function_call_param_iterator_c::visit(il_function_call_c *symbol) {

   396

  TRACE("il_function_call_c");

   397

  if (NULL != symbol->il_operand_list)

   398

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

   399

  return NULL;

   400

}

   401

   402

   403

/* | function_name '(' eol_list [il_param_list] ')' */

   404

// SYM_REF2(il_formal_funct_call_c, function_name, il_param_list)

   405

void *function_call_param_iterator_c::visit(il_formal_funct_call_c *symbol) {

   406

  TRACE("il_formal_funct_call_c");

   407

  if (NULL != symbol->il_param_list)

   408

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

   409

  return NULL;

   410

}

   411

   412

   413

/*   il_call_operator prev_declared_fb_name

   414

 * | il_call_operator prev_declared_fb_name '(' ')'

   415

 * | il_call_operator prev_declared_fb_name '(' eol_list ')'

   416

 * | il_call_operator prev_declared_fb_name '(' il_operand_list ')'

   417

 * | il_call_operator prev_declared_fb_name '(' eol_list il_param_list ')'

   418

 */

   419

// SYM_REF4(il_fb_call_c, il_call_operator, fb_name, il_operand_list, il_param_list)

   420

void *function_call_param_iterator_c::visit(il_fb_call_c *symbol) {

   421

  TRACE("il_fb_call_c");

   422

  /* the following should never occur. In reality the syntax parser

   423

   * will guarantee that they never occur, but it makes it easier to

   424

   * understand the remaining code :-)

   425

   */

   426

  //if ((NULL == symbol->il_operand_list) && (NULL == symbol->il_param_list)) ERROR;

   427

  //if ((NULL != symbol->il_operand_list) && (NULL != symbol->il_param_list)) ERROR;

   428

   429

  if (NULL != symbol->il_operand_list)

   430

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

   431

  if (NULL != symbol->il_param_list)

   432

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

   433

  return NULL;

   434

}

   435

   436

/* | il_operand_list ',' il_operand */

   437

// SYM_LIST(il_operand_list_c)

   438

void *function_call_param_iterator_c::visit(il_operand_list_c *symbol) {

   439

  TRACE("il_operand_list_c");

   440

  return search_list(symbol);

   441

}

   442

   443

   444

/* | il_initial_param_list il_param_instruction */

   445

// SYM_LIST(il_param_list_c)

   446

void *function_call_param_iterator_c::visit(il_param_list_c *symbol) {

   447

  TRACE("il_param_list_c");

   448

  return search_list(symbol);

   449

}

   450

   451

/*  il_assign_operator il_operand

   452

 * | il_assign_operator '(' eol_list simple_instr_list ')'

   453

 */

   454

// SYM_REF4(il_param_assignment_c, il_assign_operator, il_operand, simple_instr_list, unused)

   455

void *function_call_param_iterator_c::visit(il_param_assignment_c *symbol) {

   456

  TRACE("il_param_assignment_c");

   457

   458

  // TODO : We do not yet handle a instruction list passed as parameter !!!

   459

  // since we do not yet support it, it is best to simply stop than to fail silently...

   460

  if (NULL != symbol->simple_instr_list) ERROR;

   461

   462

  return handle_parameter_assignment((symbol_c *)symbol->il_assign_operator->accept(*this), symbol->il_operand);

   463

}

   464

   465

/*  il_assign_out_operator variable */

   466

// SYM_REF2(il_param_out_assignment_c, il_assign_out_operator, variable);

   467

void *function_call_param_iterator_c::visit(il_param_out_assignment_c *symbol) {

   468

  TRACE("il_param_out_assignment_c");

   469

  return handle_parameter_assignment((symbol_c *)symbol->il_assign_out_operator->accept(*this), symbol->variable);

   470

}

   471

   472

   473

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

   474

/* B 2.2 Operators */

   475

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

   476

/*  any_identifier ASSIGN */

   477

// SYM_REF1(il_assign_operator_c, variable_name)

   478

void *function_call_param_iterator_c::visit(il_assign_operator_c *symbol) {

   479

  TRACE("il_assign_operator_c");

   480

  return (void *)symbol->variable_name;

   481

}

   482

   483

/*| [NOT] any_identifier SENDTO */

   484

// SYM_REF2(il_assign_out_operator_c, option, variable_name)

   485

void *function_call_param_iterator_c::visit(il_assign_out_operator_c *symbol) {

   486

  TRACE("il_assign_out_operator_c");

   487

   488

  // TODO : Handle not_param !!!

   489

  // we do not yet support it, so it is best to simply stop than to fail silently...

   490

  // if (NULL != symbol->option) ERROR;

   491

   492

  return (void *)symbol->variable_name;

   493

}

   494

   495

   496

   497

   498

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

   499

/* B.3 - Language ST (Structured Text) */

   500

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

   501

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

   502

/* B 3.1 - Expressions */

   503

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

   504

   505

/*

   506

SYM_REF2(function_invocation_c, function_name, parameter_assignment_list)

   507

*/

   508

void *function_call_param_iterator_c::visit(function_invocation_c *symbol) {

   509

  TRACE("function_invocation_c");

   510

  /* If the syntax parser is working correctly, exactly one of the 

   511

   * following two symbols will be NULL, while the other is != NULL.

   512

   */

   513

  if (symbol == (function_invocation_c *)f_call) {

   514

	if (symbol->   formal_param_list != NULL) return symbol->   formal_param_list->accept(*this);

   515

    if (symbol->nonformal_param_list != NULL) return symbol->nonformal_param_list->accept(*this);

   516

  }

   517

   518

  return NULL;