1 /*

     2  * (c) 2003 Mario de Sousa

     3  *

     4  * 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  *

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

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

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

    11  * Public License for more details.

    12  *

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

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

    15  */

    16 

    17 /*

    18  * An IEC 61131-3 IL and ST compiler.

    19  *

    20  * Based on the

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

    22  *

    23  */

    24 

    25 

    26 /*

    27  * Function parameter iterator.

    28  * Iterate through the in/out parameters of a function declaration.

    29  * Function blocks are also suported.

    30  *

    31  * This is part of the 4th stage that generates

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

    33  * code.

    34  */

    35 

    36 /* Given a function_declaration_c, iterate through each

    37  * function in/out/inout parameter, returning the name

    38  * of each parameter...function_param_iterator_c

    39  */

    40 

    41 

    42 

    43 #include "function_param_iterator.hh"

    44 #include "spec_init_separator.hh"

    45 #include <strings.h>

    46 

    47 

    48 //#define DEBUG

    49 #ifdef DEBUG

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

    51 #else

    52 #define TRACE(classname)

    53 #endif

    54 

    55 

    56 #define ERROR error_exit(__FILE__,__LINE__)

    57 /* function defined in main.cc */

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

    59 

    60 

    61 

    62 void* function_param_iterator_c::handle_param_list(list_c *list) {

    63   if (next_param <= param_count + list->n)

    64     return list->elements[next_param - param_count - 1];

    65 

    66   /* the desired param is not on this list... */

    67   param_count += list->n;

    68  return NULL;

    69 }

    70 

    71 void* function_param_iterator_c::handle_single_param(symbol_c *var_name) {

    72   param_count++;

    73   if (next_param == param_count)

    74     return var_name;

    75 

    76   /* not yet the desired param... */

    77  return NULL;

    78 }

    79 

    80 void* function_param_iterator_c::iterate_list(list_c *list) {

    81   void *res;

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

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

    84     if (res != NULL)

    85         return res;

    86   }

    87   return NULL;

    88 }

    89 

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

    91 void function_param_iterator_c::reset(void) {

    92   next_param = param_count = 0;

    93   current_param_name = NULL;

    94   current_param_type = current_param_default_value = NULL;

    95   en_declared = false;

    96   eno_declared = false;

    97 }

    98 

    99 /* initialise the iterator object.

   100  * We must be given a reference to the function declaration

   101  * that will be analysed...

   102  */

   103 function_param_iterator_c::function_param_iterator_c(function_declaration_c *f_decl) {

   104   this->f_decl = f_decl;

   105   reset();

   106 }

   107 

   108 /* initialise the iterator object.

   109  * We must be given a reference to the function block declaration

   110  * that will be analysed...

   111  */

   112 function_param_iterator_c::function_param_iterator_c(function_block_declaration_c *fb_decl) {

   113   this->f_decl = fb_decl;

   114   reset();

   115 }

   116 

   117 /* initialise the iterator object.

   118  * We must be given a reference to the program declaration

   119  * that will be analysed...

   120  */

   121 function_param_iterator_c::function_param_iterator_c(program_declaration_c *p_decl) {

   122   this->f_decl = p_decl;

   123   reset();

   124 }

   125 

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

   127  * the object references on parameter _before_ the first, so

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

   129  * reference the first parameter...

   130  *

   131  * Returns the parameter's name!

   132  */

   133 identifier_c *function_param_iterator_c::next(void) {

   134   void *res;

   135   identifier_c *identifier;

   136   param_count = 0;

   137   next_param++;

   138   res = f_decl->accept(*this);

   139   if (res != NULL) {

   140     symbol_c *sym = (symbol_c *)res;

   141     identifier = dynamic_cast<identifier_c *>(sym);

   142     if (identifier == NULL)

   143       ERROR;

   144   }

   145   else if (!en_declared) {

   146     current_param_direction = direction_in;

   147     identifier = declare_en_param();

   148   }

   149   else if (!eno_declared) {

   150     current_param_direction = direction_out;

   151     identifier = declare_eno_param();

   152   }

   153   else

   154     return NULL;

   155   

   156   current_param_name = identifier;

   157   return current_param_name;

   158 }

   159 

   160 identifier_c *function_param_iterator_c::declare_en_param(void) {

   161   en_declared = true;

   162   identifier_c *identifier = new identifier_c("EN");

   163   current_param_type = (symbol_c*)(new bool_type_name_c());

   164   current_param_default_value = (symbol_c*)(new boolean_literal_c(current_param_type, new boolean_true_c()));

   165   return identifier;

   166 }

   167 

   168 identifier_c *function_param_iterator_c::declare_eno_param(void) {

   169   eno_declared = true;

   170   identifier_c *identifier = new identifier_c("ENO");

   171   current_param_type = (symbol_c*)(new bool_type_name_c());

   172   current_param_default_value = NULL;

   173   return identifier;

   174 }

   175 

   176 /* Returns the currently referenced parameter's default value,

   177  * or NULL if none is specified in the function declrataion itself.

   178  */

   179 symbol_c *function_param_iterator_c::default_value(void) {

   180   return current_param_default_value;

   181 }

   182 

   183 /* Returns the currently referenced parameter's type name. */

   184 symbol_c *function_param_iterator_c::param_type(void) {

   185   return current_param_type;

   186 }

   187 

   188 /* Returns the currently referenced parameter's data passing direction.

   189  * i.e. VAR_INPUT, VAR_OUTPUT or VAR_INOUT

   190  */

   191 function_param_iterator_c::param_direction_t function_param_iterator_c::param_direction(void) {

   192   return current_param_direction;

   193 }

   194 

   195 /****************************************/

   196 /* 1.4.3 - Declaration & Initialisation */

   197 /****************************************/

   198 void *function_param_iterator_c::visit(input_declarations_c *symbol) {

   199   TRACE("input_declarations_c");

   200   current_param_direction = direction_in;

   201   return symbol->input_declaration_list->accept(*this);

   202 }

   203 

   204 void *function_param_iterator_c::visit(input_declaration_list_c *symbol) {TRACE("input_declaration_list_c"); return iterate_list(symbol);}

   205 

   206 void *function_param_iterator_c::visit(edge_declaration_c *symbol) {TRACE("edge_declaration_c"); return symbol->var1_list->accept(*this);}

   207 

   208 void *function_param_iterator_c::visit(en_param_declaration_c *symbol) {

   209   TRACE("en_param_declaration_c");

   210   if (en_declared) ERROR;

   211   return (void *)declare_en_param();

   212 }

   213 

   214 /* var1_list ':' array_spec_init */

   215 //SYM_REF2(array_var_init_decl_c, var1_list, array_spec_init)

   216 void *function_param_iterator_c::visit(array_var_init_decl_c *symbol) {TRACE("array_var_init_decl_c"); return symbol->var1_list->accept(*this);}

   217 

   218 /*  var1_list ':' initialized_structure */

   219 //SYM_REF2(structured_var_init_decl_c, var1_list, initialized_structure)

   220 void *function_param_iterator_c::visit(structured_var_init_decl_c *symbol) {TRACE("structured_var_init_decl_c"); return symbol->var1_list->accept(*this);}

   221 

   222 void *function_param_iterator_c::visit(output_declarations_c *symbol) {

   223   TRACE("output_declarations_c");

   224   current_param_direction = direction_out;

   225   return symbol->var_init_decl_list->accept(*this);

   226 }

   227 void *function_param_iterator_c::visit(eno_param_declaration_c *symbol) {

   228   TRACE("eno_param_declaration_c");

   229   if (eno_declared) ERROR;

   230   return (void *)declare_eno_param();

   231 }

   232 void *function_param_iterator_c::visit(input_output_declarations_c *symbol) {

   233   TRACE("input_output_declarations_c");

   234   current_param_direction = direction_inout;

   235   return symbol->var_declaration_list->accept(*this);

   236 }

   237 void *function_param_iterator_c::visit(var_declaration_list_c *symbol) {TRACE("var_declaration_list_c"); return iterate_list(symbol);}

   238 

   239 /*  var1_list ':' array_specification */

   240 //SYM_REF2(array_var_declaration_c, var1_list, array_specification)

   241 void *function_param_iterator_c::visit(array_var_declaration_c *symbol) {TRACE("array_var_declaration_c"); return symbol->var1_list->accept(*this);}

   242 

   243 /*  var1_list ':' structure_type_name */

   244 //SYM_REF2(structured_var_declaration_c, var1_list, structure_type_name)

   245 void *function_param_iterator_c::visit(structured_var_declaration_c *symbol) {TRACE("structured_var_declaration_c"); return symbol->var1_list->accept(*this);}

   246 

   247 /* VAR [CONSTANT] var_init_decl_list END_VAR */

   248 void *function_param_iterator_c::visit(var_declarations_c *symbol) {TRACE("var_declarations_c"); return NULL;}

   249 

   250 /*| VAR_EXTERNAL [CONSTANT] external_declaration_list END_VAR */

   251 /* option -> may be NULL ! */

   252 // SYM_REF2(external_var_declarations_c, option, external_declaration_list)

   253 void *function_param_iterator_c::visit(external_var_declarations_c *symbol) {

   254   TRACE("external_var_declarations_c");

   255   current_param_direction = direction_extref;

   256   return symbol->external_declaration_list->accept(*this);

   257 }

   258 

   259 /* helper symbol for external_var_declarations */

   260 /*| external_declaration_list external_declaration';' */

   261 // SYM_LIST(external_declaration_list_c)

   262 void *function_param_iterator_c::visit(external_declaration_list_c *symbol) {TRACE("external_declaration_list_c"); return iterate_list(symbol);}

   263 

   264 /*  global_var_name ':' (simple_specification|subrange_specification|enumerated_specification|array_specification|prev_declared_structure_type_name|function_block_type_name */

   265 //SYM_REF2(external_declaration_c, global_var_name, specification)

   266 void *function_param_iterator_c::visit(external_declaration_c *symbol) {

   267   TRACE("external_declaration_c");

   268   /* It is OK to store these values in the current_param_XXX

   269    * variables, because if the desired parameter is not in the

   270    * variable list we will be analysing, the current_param_XXXX

   271    * variables will get overwritten when we visit the next

   272    * var1_init_decl_c list!

   273    */

   274   current_param_default_value = spec_init_sperator_c::get_init(symbol->specification);

   275   current_param_type = spec_init_sperator_c::get_spec(symbol->specification);

   276 

   277   return handle_single_param(symbol->global_var_name);

   278 }

   279 

   280 

   281 #if 0

   282 /*| VAR_GLOBAL [CONSTANT|RETAIN] global_var_decl_list END_VAR */

   283 /* option -> may be NULL ! */

   284 SYM_REF2(global_var_declarations_c, option, global_var_decl_list)

   285 

   286 /* helper symbol for global_var_declarations */

   287 /*| global_var_decl_list global_var_decl ';' */

   288 SYM_LIST(global_var_decl_list_c)

   289 

   290 /*| global_var_spec ':' [located_var_spec_init|function_block_type_name] */

   291 /* type_specification ->may be NULL ! */

   292 SYM_REF2(global_var_decl_c, global_var_spec, type_specification)

   293 

   294 /*| global_var_name location */

   295 SYM_REF2(global_var_spec_c, global_var_name, location)

   296 

   297 /*  AT direct_variable */

   298 SYM_REF2(location_c, direct_variable, unused)

   299 

   300 /*| global_var_list ',' global_var_name */

   301 SYM_LIST(global_var_list_c)

   302 

   303 /*  var1_list ':' single_byte_string_spec */

   304 SYM_REF2(single_byte_string_var_declaration_c, var1_list, single_byte_string_spec)

   305 

   306 /*  STRING ['[' integer ']'] [ASSIGN single_byte_character_string] */

   307 /* integer ->may be NULL ! */

   308 /* single_byte_character_string ->may be NULL ! */

   309 SYM_REF2(single_byte_string_spec_c, integer, single_byte_character_string)

   310 

   311 /*  var1_list ':' double_byte_string_spec */

   312 SYM_REF2(double_byte_string_var_declaration_c, var1_list, double_byte_string_spec)

   313 

   314 /*  WSTRING ['[' integer ']'] [ASSIGN double_byte_character_string] */

   315 /* integer ->may be NULL ! */

   316 /* double_byte_character_string ->may be NULL ! */

   317 SYM_REF2(double_byte_string_spec_c, integer, double_byte_character_string)

   318 

   319 /*| VAR [RETAIN|NON_RETAIN] incompl_located_var_decl_list END_VAR */

   320 /* option ->may be NULL ! */

   321 SYM_REF2(incompl_located_var_declarations_c, option, incompl_located_var_decl_list)

   322 

   323 /* helper symbol for incompl_located_var_declarations */

   324 /*| incompl_located_var_decl_list incompl_located_var_decl ';' */

   325 SYM_LIST(incompl_located_var_decl_list_c)

   326 

   327 /*  variable_name incompl_location ':' var_spec */

   328 SYM_REF4(incompl_located_var_decl_c, variable_name, incompl_location, var_spec, unused)

   329 

   330 /*  AT incompl_location_token */

   331 SYM_TOKEN(incompl_location_c)

   332 #endif

   333 

   334 

   335 void *function_param_iterator_c::visit(var1_init_decl_c *symbol) {

   336   TRACE("var1_init_decl_c");

   337   /* It is OK to store these values in the current_param_XXX

   338    * variables, because if the desired parameter is not in the

   339    * variable list we will be analysing, the current_param_XXXX

   340    * variables will get overwritten when we visit the next

   341    * var1_init_decl_c list!

   342    */

   343   current_param_default_value = spec_init_sperator_c::get_init(symbol->spec_init);

   344   current_param_type = spec_init_sperator_c::get_spec(symbol->spec_init);

   345 

   346   return symbol->var1_list->accept(*this);

   347 }

   348 

   349 

   350 

   351 void *function_param_iterator_c::visit(var1_list_c *symbol) {

   352   TRACE("var1_list_c");

   353   return handle_param_list(symbol);

   354 }

   355 

   356 void *function_param_iterator_c::visit(var_init_decl_list_c *symbol) {TRACE("var_init_decl_list_c"); return iterate_list(symbol);}

   357 

   358 

   359 /***********************/

   360 /* B 1.5.1 - Functions */

   361 /***********************/

   362 void *function_param_iterator_c::visit(function_declaration_c *symbol) {TRACE("function_declaration_c"); return symbol->var_declarations_list->accept(*this);}

   363 /* intermediate helper symbol for function_declaration */

   364 void *function_param_iterator_c::visit(var_declarations_list_c *symbol) {TRACE("var_declarations_list_c"); return iterate_list(symbol);}

   365 void *function_param_iterator_c::visit(function_var_decls_c *symbol) {TRACE("function_var_decls_c"); /* ignore */ return NULL;}

   366 

   367 

   368 /*****************************/

   369 /* B 1.5.2 - Function Blocks */

   370 /*****************************/

   371 /*  FUNCTION_BLOCK derived_function_block_name io_OR_other_var_declarations function_block_body END_FUNCTION_BLOCK */

   372 void *function_param_iterator_c::visit(function_block_declaration_c *symbol) {TRACE("function_block_declaration_c"); return symbol->var_declarations->accept(*this);}

   373 

   374 /* intermediate helper symbol for function_declaration */

   375 /*  { io_var_declarations | other_var_declarations }   */

   376 /*

   377  * NOTE: we re-use the var_declarations_list_c

   378  */

   379 

   380 /*  VAR_TEMP temp_var_decl_list END_VAR */

   381 void *function_param_iterator_c::visit(temp_var_decls_c *symbol) {TRACE("temp_var_decls_c"); /* ignore */ return NULL;}

   382 void *function_param_iterator_c::visit(temp_var_decls_list_c *symbol) {TRACE("temp_var_decls_list_c"); /* ignore */ return NULL;}

   383 

   384 /*  VAR NON_RETAIN var_init_decl_list END_VAR */

   385 void *function_param_iterator_c::visit(non_retentive_var_decls_c *symbol) {TRACE("non_retentive_var_decls_c"); /* ignore */ return NULL;}

   386 

   387 

   388 /**********************/

   389 /* B 1.5.3 - Programs */

   390 /**********************/

   391 /*  PROGRAM program_type_name program_var_declarations_list function_block_body END_PROGRAM */

   392 // SYM_REF4(program_declaration_c, program_type_name, var_declarations, function_block_body, unused)

   393 void *function_param_iterator_c::visit(program_declaration_c *symbol) {TRACE("program_declaration_c"); return symbol->var_declarations->accept(*this);}

   394 

   395 /* intermediate helper symbol for program_declaration_c */

   396 /*  { io_var_declarations | other_var_declarations }   */

   397 /*

   398  * NOTE: we re-use the var_declarations_list_c

   399  */

   400 

   401 

   402 

   403 

   404 

   405