etisserant@0: /*
etisserant@0:  * (c) 2003 Mario de Sousa
etisserant@0:  *
etisserant@0:  * Offered to the public under the terms of the GNU General Public License
etisserant@0:  * as published by the Free Software Foundation; either version 2 of the
etisserant@0:  * License, or (at your option) any later version.
etisserant@0:  *
etisserant@0:  * This program is distributed in the hope that it will be useful, but
etisserant@0:  * WITHOUT ANY WARRANTY; without even the implied warranty of
etisserant@0:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
etisserant@0:  * Public License for more details.
etisserant@0:  *
etisserant@0:  * This code is made available on the understanding that it will not be
etisserant@0:  * used in safety-critical situations without a full and competent review.
etisserant@0:  */
etisserant@0: 
etisserant@0: /*
etisserant@0:  * An IEC 61131-3 IL and ST compiler.
etisserant@0:  *
etisserant@0:  * Based on the
etisserant@0:  * FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)
etisserant@0:  *
etisserant@0:  */
etisserant@0: 
etisserant@0: /* Determine the data type of a specific variable instance, including
etisserant@0:  * function block instances.
etisserant@0:  * A reference to the relevant variable declaration is returned.
etisserant@0:  * The variable instance may NOT be a member of a structure of a memeber
etisserant@0:  * of a structure of an element of an array of ...
etisserant@0:  *
etisserant@0:  * example:
etisserant@0:  *    window.points[1].coordinate.x
etisserant@0:  *    window.points[1].colour
etisserant@0:  *    etc... ARE NOT ALLOWED!
etisserant@0:  *
etisserant@0:  * This class must only be passed the name of the variable that will appear
etisserant@0:  * in the variable declaration. In the above examples, this would be
etisserant@0:  *   'window' !!
etisserant@0:  *
etisserant@0:  *
etisserant@0:  * If you need to pass a complete name of a variable instance (such as
etisserant@0:  * 'window.points[1].coordinate.x') use the search_varfb_instance_type_c instead!
etisserant@0:  */
etisserant@0: /* Note that current_type_decl that this class returns may reference the
etisserant@0:  * name of a type, or the type declaration itself!
etisserant@0:  * For an example of the first, consider a variable declared as ...
etisserant@0:  * x : AAA;
etisserant@0:  * where the AAA type is previously declared as whatever.
etisserant@0:  * For an example of the second, consider a variable declared as ...
etisserant@0:  * x : array of int [10];  ---->  is allowed
etisserant@0:  *
etisserant@0:  * If it is the first, we will return a reference to the name, if the second
etisserant@0:  * we return a reference to the declaration!!
etisserant@0:  */
etisserant@0: class search_var_instance_decl_c: public search_visitor_c {
etisserant@0: 
etisserant@0:   private:
etisserant@0:     symbol_c *search_scope;
etisserant@0:     symbol_c *search_name;
etisserant@0:     symbol_c *current_type_decl;
etisserant@0: 
etisserant@0:   public:
etisserant@0:     search_var_instance_decl_c(symbol_c *search_scope) {
etisserant@0:       this->search_scope = search_scope;
etisserant@0:       this->search_name = NULL;
etisserant@0:       this->current_type_decl = NULL;
etisserant@0:     }
etisserant@0: 
etisserant@0:     symbol_c *get_decl(symbol_c *variable_instance_name) {
etisserant@0:       this->search_name = variable_instance_name;
etisserant@0:       return (symbol_c *)search_scope->accept(*this);
etisserant@0:     }
etisserant@0: 
etisserant@0:   public:
etisserant@0: /***************************/
etisserant@0: /* B 0 - Programming Model */
etisserant@0: /***************************/
etisserant@0:     void *visit(library_c *symbol) {
etisserant@0:       /* we do not want to search multiple declaration scopes,
etisserant@0:        * so we do not visit all the functions, fucntion blocks, etc...
etisserant@0:        */
etisserant@0:       return NULL;
etisserant@0:     }
etisserant@0: 
etisserant@0: 
etisserant@0: 
etisserant@0: /******************************************/
etisserant@0: /* B 1.4.3 - Declaration & Initialisation */
etisserant@0: /******************************************/
etisserant@0: /* edge -> The F_EDGE or R_EDGE directive */
etisserant@0: // SYM_REF2(edge_declaration_c, edge, var1_list)
etisserant@0: // TODO
etisserant@0: 
etisserant@0: /* var1_list is one of the following...
etisserant@0:  *    simple_spec_init_c *
etisserant@0:  *    subrange_spec_init_c *
etisserant@0:  *    enumerated_spec_init_c *
etisserant@0:  */
etisserant@0: // SYM_REF2(var1_init_decl_c, var1_list, spec_init)
etisserant@0:     void *visit(var1_init_decl_c *symbol) {
etisserant@0:       current_type_decl = symbol->spec_init;
etisserant@0:       return symbol->var1_list->accept(*this);
etisserant@0:     }
etisserant@0: 
etisserant@0: /* var1_list ',' variable_name */
etisserant@0: // SYM_LIST(var1_list_c)
etisserant@0:     void *visit(var1_list_c *symbol) {
etisserant@0:       list_c *list = symbol;
etisserant@0:       for(int i = 0; i < list->n; i++) {
etisserant@0:         if (compare_identifiers(list->elements[i], search_name) == 0)
etisserant@0: 	  /* by now, current_type_decl should be != NULL */
etisserant@0:           return current_type_decl;
etisserant@0:       }
etisserant@0:       return NULL;
etisserant@0:     }
etisserant@0: 
etisserant@0: /* name_list ':' function_block_type_name ASSIGN structure_initialization */
etisserant@0: /* structure_initialization -> may be NULL ! */
etisserant@0:     void *visit(fb_name_decl_c *symbol) {
etisserant@0:       current_type_decl = symbol->function_block_type_name;
etisserant@0:       return symbol->fb_name_list->accept(*this);
etisserant@0:     }
etisserant@0: 
etisserant@0: /* name_list ',' fb_name */
etisserant@0:     void *visit(fb_name_list_c *symbol) {
etisserant@0:       list_c *list = symbol;
etisserant@0:       for(int i = 0; i < list->n; i++) {
etisserant@0:         if (compare_identifiers(list->elements[i], search_name) == 0)
etisserant@0: 	  /* by now, current_fb_declaration should be != NULL */
etisserant@0:           return current_type_decl;
etisserant@0:       }
etisserant@0:       return NULL;
etisserant@0:     }
etisserant@0: 
etisserant@0: /* var1_list ':' array_spec_init */
etisserant@0: // SYM_REF2(array_var_init_decl_c, var1_list, array_spec_init)
etisserant@0:     void *visit(array_var_init_decl_c *symbol) {
etisserant@0:       current_type_decl = symbol->array_spec_init;
etisserant@0:       return symbol->var1_list->accept(*this);
etisserant@0:     }
etisserant@0: 
etisserant@0: /*  var1_list ':' initialized_structure */
etisserant@0: // SYM_REF2(structured_var_init_decl_c, var1_list, initialized_structure)
etisserant@0:     void *visit(structured_var_init_decl_c *symbol) {
etisserant@0:       current_type_decl = symbol->initialized_structure;
etisserant@0:       return symbol->var1_list->accept(*this);
etisserant@0:     }
etisserant@0: 
etisserant@0: /*  var1_list ':' array_specification */
etisserant@0: // SYM_REF2(array_var_declaration_c, var1_list, array_specification)
etisserant@0:     void *visit(array_var_declaration_c *symbol) {
etisserant@0:       current_type_decl = symbol->array_specification;
etisserant@0:       return symbol->var1_list->accept(*this);
etisserant@0:     }
etisserant@0: 
etisserant@0: /*  var1_list ':' structure_type_name */
etisserant@0: // SYM_REF2(structured_var_declaration_c, var1_list, structure_type_name)
etisserant@0:     void *visit(structured_var_declaration_c *symbol) {
etisserant@0:       current_type_decl = symbol->structure_type_name;
etisserant@0:       return symbol->var1_list->accept(*this);
etisserant@0:     }
etisserant@0: 
etisserant@0: /*  [variable_name] location ':' located_var_spec_init */
etisserant@0: /* variable_name -> may be NULL ! */
etisserant@0: // SYM_REF4(located_var_decl_c, variable_name, location, located_var_spec_init, unused)
etisserant@0: // TODO!!
etisserant@0: 
etisserant@0: /*  global_var_name ':' (simple_specification|subrange_specification|enumerated_specification|array_specification|prev_declared_structure_type_name|function_block_type_name */
etisserant@0: // SYM_REF2(external_declaration_c, global_var_name, specification)
etisserant@0:     void *visit(external_declaration_c *symbol) {
etisserant@0:       if (compare_identifiers(symbol->global_var_name, search_name) == 0)
etisserant@0:           return symbol->specification;
etisserant@0:       return NULL;
etisserant@0:     }
etisserant@0: 
etisserant@0: /*| global_var_spec ':' [located_var_spec_init|function_block_type_name] */
etisserant@0: /* type_specification ->may be NULL ! */
etisserant@0: // SYM_REF2(global_var_decl_c, global_var_spec, type_specification)
etisserant@0: // TODO!!
etisserant@0: 
etisserant@0: /*| global_var_name location */
etisserant@0: // SYM_REF2(global_var_spec_c, global_var_name, location)
etisserant@0: // TODO!!
etisserant@0: 
etisserant@0: /*  AT direct_variable */
etisserant@0: // SYM_REF2(location_c, direct_variable, unused)
etisserant@0: // TODO!!
etisserant@0: 
etisserant@0: /*| global_var_list ',' global_var_name */
etisserant@0: // SYM_LIST(global_var_list_c)
etisserant@0: // TODO!!
etisserant@0: 
etisserant@0: /*  var1_list ':' single_byte_string_spec */
etisserant@0: // SYM_REF2(single_byte_string_var_declaration_c, var1_list, single_byte_string_spec)
etisserant@0:     void *visit(single_byte_string_var_declaration_c *symbol) {
etisserant@0:       current_type_decl = symbol->single_byte_string_spec;
etisserant@0:       return symbol->var1_list->accept(*this);
etisserant@0:     }
etisserant@0: 
etisserant@0: /*  STRING ['[' integer ']'] [ASSIGN single_byte_character_string] */
etisserant@0: /* integer ->may be NULL ! */
etisserant@0: /* single_byte_character_string ->may be NULL ! */
etisserant@0: // SYM_REF2(single_byte_string_spec_c, integer, single_byte_character_string)
etisserant@0: // TODO!!
etisserant@0: 
etisserant@0: /*  var1_list ':' double_byte_string_spec */
etisserant@0: // SYM_REF2(double_byte_string_var_declaration_c, var1_list, double_byte_string_spec)
etisserant@0:     void *visit(double_byte_string_var_declaration_c *symbol) {
etisserant@0:       current_type_decl = symbol->double_byte_string_spec;
etisserant@0:       return symbol->var1_list->accept(*this);
etisserant@0:     }
etisserant@0: 
etisserant@0: /*  WSTRING ['[' integer ']'] [ASSIGN double_byte_character_string] */
etisserant@0: /* integer ->may be NULL ! */
etisserant@0: /* double_byte_character_string ->may be NULL ! */
etisserant@0: // SYM_REF2(double_byte_string_spec_c, integer, double_byte_character_string)
etisserant@0: // TODO!!
etisserant@0: 
etisserant@0: /*  variable_name incompl_location ':' var_spec */
etisserant@0: // SYM_REF4(incompl_located_var_decl_c, variable_name, incompl_location, var_spec, unused)
etisserant@0: // TODO!!
etisserant@0: 
etisserant@0: /*  AT incompl_location_token */
etisserant@0: // SYM_TOKEN(incompl_location_c)
etisserant@0: // TODO!!
etisserant@0: 
etisserant@0: 
etisserant@0: /**************************************/
etisserant@0: /* B.1.5 - Program organization units */
etisserant@0: /**************************************/
etisserant@0: /***********************/
etisserant@0: /* B 1.5.1 - Functions */
etisserant@0: /***********************/
etisserant@0: // SYM_REF4(function_declaration_c, derived_function_name, type_name, var_declarations_list, function_body)
etisserant@0:     void *visit(function_declaration_c *symbol) {
etisserant@0:       /* functions have a variable named after themselves, to store
etisserant@0:        * the variable that will be returned!!
etisserant@0:        */
etisserant@0:       if (compare_identifiers(symbol->derived_function_name, search_name) == 0)
etisserant@0:           return symbol->type_name;
etisserant@0: 
etisserant@0:       /* no need to search through all the body, so we only
etisserant@0:        * visit the variable declarations...!
etisserant@0:        */
etisserant@0:       return symbol->var_declarations_list->accept(*this);
etisserant@0:     }
etisserant@0: 
etisserant@0: /*****************************/
etisserant@0: /* B 1.5.2 - Function Blocks */
etisserant@0: /*****************************/
etisserant@0:     void *visit(function_block_declaration_c *symbol) {
etisserant@0:       /* no need to search through all the body, so we only
etisserant@0:        * visit the variable declarations...!
etisserant@0:        */
etisserant@0:       return symbol->var_declarations->accept(*this);
etisserant@0:     }
etisserant@0: 
etisserant@0: /**********************/
etisserant@0: /* B 1.5.3 - Programs */
etisserant@0: /**********************/
etisserant@0:     void *visit(program_declaration_c *symbol) {
etisserant@0:       /* no need to search through all the body, so we only
etisserant@0:        * visit the variable declarations...!
etisserant@0:        */
etisserant@0:       return symbol->var_declarations->accept(*this);
etisserant@0:     }
etisserant@0: 
etisserant@0: 
etisserant@0: #if 0
etisserant@0: /*********************/
etisserant@0: /* B 1.4 - Variables */
etisserant@0: /*********************/
etisserant@0: SYM_REF2(symbolic_variable_c, var_name, unused)
etisserant@0: 
etisserant@0: /********************************************/
etisserant@0: /* B.1.4.1   Directly Represented Variables */
etisserant@0: /********************************************/
etisserant@0: SYM_TOKEN(direct_variable_c)
etisserant@0: 
etisserant@0: /*************************************/
etisserant@0: /* B.1.4.2   Multi-element Variables */
etisserant@0: /*************************************/
etisserant@0: /*  subscripted_variable '[' subscript_list ']' */
etisserant@0: SYM_REF2(array_variable_c, subscripted_variable, subscript_list)
etisserant@0: 
etisserant@0: /* subscript_list ',' subscript */
etisserant@0: SYM_LIST(subscript_list_c)
etisserant@0: 
etisserant@0: /*  record_variable '.' field_selector */
etisserant@0: /*  WARNING: input and/or output variables of function blocks
etisserant@0:  *           may be accessed as fields of a tructured variable!
etisserant@0:  *           Code handling a structured_variable_c must take
etisserant@0:  *           this into account!
etisserant@0:  */
etisserant@0: SYM_REF2(structured_variable_c, record_variable, field_selector)
etisserant@0: 
etisserant@0: 
etisserant@0: #endif
etisserant@0: };
etisserant@0: 
etisserant@0: 
etisserant@0: 
etisserant@0: 
etisserant@0: