--- a/stage4/generate_cc/search_varfb_instance_type.cc Tue Oct 23 10:35:58 2007 +0200
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,293 +0,0 @@
-/*
- * (c) 2003 Mario de Sousa
- *
- * Offered to the public under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2 of the
- * License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
- * Public License for more details.
- *
- * This code is made available on the understanding that it will not be
- * used in safety-critical situations without a full and competent review.
- */
-
-/*
- * An IEC 61131-3 IL and ST compiler.
- *
- * Based on the
- * FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)
- *
- */
-
-
-
-/* Determine the data type of a variable.
- * The variable may be a simple variable, a function block instance, a
- * struture element within a data structured type (a struct or a fb), or
- * an array element.
- * A mixture of array element of a structure element of a structure element
- * of a .... is also suported!
- *
- * A reference to the relevant base type __definition__ is returned.
- * This means that if we find that the variable is of type MY_INT,
- * which was previously declared to be
- * TYPE MY_INT: INT := 9;
- * this class wil return INT, and __not__ MY_INT !!
- *
- *
- * example:
- * window.points[1].coordinate.x
- * window.points[1].colour
- * etc... ARE ALLOWED!
- *
- * This class must be passed the scope within which the
- * variable was declared, and the variable name...
- */
-class search_varfb_instance_type_c: public search_base_type_c {
- private:
- search_var_instance_decl_c search_var_instance_decl;
- decompose_var_instance_name_c *decompose_var_instance_name;
- symbol_c *current_structelement_name;
-
- public:
- search_varfb_instance_type_c(symbol_c *search_scope): search_var_instance_decl(search_scope) {
- this->decompose_var_instance_name = NULL;
- this->current_structelement_name = NULL;
- }
-
-
- symbol_c *get_type(symbol_c *variable_name) {
- this->current_structelement_name = NULL;
- this->decompose_var_instance_name = new decompose_var_instance_name_c(variable_name);
- if (NULL == decompose_var_instance_name) ERROR;
-
- /* find the part of the variable name that will appear in the
- * variable declaration, for e.g., in window.point.x, this would be
- * window!
- */
- symbol_c *var_name_part = decompose_var_instance_name->next_part();
- if (NULL == var_name_part) ERROR;
-
- /* Now we try to find the variable instance declaration, to determine its type... */
- symbol_c *var_decl = search_var_instance_decl.get_decl(var_name_part);
- if (NULL == var_decl) {
- /* variable instance declaration not found! */
- return NULL;
- }
-
- /* if it is a struct or function block, we must search the type
- * of the struct or function block member.
- * This is done by this class visiting the var_decl.
- * This class, while visiting, will recursively call
- * decompose_var_instance_name->get_next() when and if required...
- */
- symbol_c *res = (symbol_c *)var_decl->accept(*this);
- if (NULL == res) ERROR;
-
- /* make sure that we have decomposed all strcuture elements of the variable name */
- symbol_c *var_name = decompose_var_instance_name->next_part();
- if (NULL != var_name) ERROR;
-
- return res;
- }
-
- unsigned int get_vartype(symbol_c *variable_name) {
- this->current_structelement_name = NULL;
- this->decompose_var_instance_name = new decompose_var_instance_name_c(variable_name);
- if (NULL == decompose_var_instance_name) ERROR;
-
- /* find the part of the variable name that will appear in the
- * variable declaration, for e.g., in window.point.x, this would be
- * window!
- */
- symbol_c *var_name_part = decompose_var_instance_name->next_part();
- if (NULL == var_name_part) ERROR;
-
- /* Now we try to find the variable instance declaration, to determine its type... */
- symbol_c *var_decl = search_var_instance_decl.get_decl(var_name_part);
- if (NULL == var_decl) {
- /* variable instance declaration not found! */
- return 0;
- }
-
- /* if it is a struct or function block, we must search the type
- * of the struct or function block member.
- * This is done by this class visiting the var_decl.
- * This class, while visiting, will recursively call
- * decompose_var_instance_name->get_next() when and if required...
- */
- unsigned int res = search_var_instance_decl.get_vartype();
-
- /* make sure that we have decomposed all strcuture elements of the variable name */
- symbol_c *var_name = decompose_var_instance_name->next_part();
- if (NULL != var_name) ERROR;
-
- return res;
- }
-
- private:
- /* a helper function... */
- void *visit_list(list_c *list) {
- if (NULL == current_structelement_name) ERROR;
-
- for(int i = 0; i < list->n; i++) {
- void *res = list->elements[i]->accept(*this);
- if (res != NULL)
- return res;
- }
- /* not found! */
- return NULL;
- }
-
- /* a helper function... */
- void *base_type(symbol_c *symbol) {
- search_base_type_c search_base_type;
- return symbol->accept(search_base_type);
- }
-
-
- private:
- /* We override the base class' visitor to identifier_c.
- * This is so because the base class does not consider a function block
- * to be a type, unlike this class that allows a variable instance
- * of a function block type...
- */
- void *visit(identifier_c *type_name) {
- /* look up the type declaration... */
- symbol_c *fb_decl = function_block_type_symtable.find_value(type_name);
- if (fb_decl != function_block_type_symtable.end_value())
- /* Type declaration found!! */
- return fb_decl->accept(*this);
-
- /* No. It is not a function block, so we let
- * the base class take care of it...
- */
- return search_base_type_c::visit(type_name);
- }
-
-/********************************/
-/* B 1.3.3 - Derived data types */
-/********************************/
-/* structure_type_name ':' structure_specification */
- void *visit(structure_type_declaration_c *symbol) {
- return symbol->structure_specification->accept(*this);
- /* NOTE: structure_specification will point to either a
- * initialized_structure_c
- * OR A
- * structure_element_declaration_list_c
- */
- }
-
-/* structure_type_name ASSIGN structure_initialization */
-/* structure_initialization may be NULL ! */
-// SYM_REF2(initialized_structure_c, structure_type_name, structure_initialization)
- void *visit(initialized_structure_c *symbol) {
- /* make sure that we have decomposed all strcuture elements of the variable name */
- symbol_c *var_name = decompose_var_instance_name->next_part();
- if (NULL == var_name) {
- /* this is it... !
- * No need to look any further...
- */
- /* NOTE: we could simply do a
- * return (void *)symbol;
- * nevertheless, note that this search_varfb_instance_type_c
- * class inherits from the search_base_type_c class,
- * which means that it will usually return the base type,
- * and not the derived type (*). If we are to be consistent,
- * we should guarantee that we always return the base type.
- * To do this we could use
- * return (void *)symbol->accept(*this);
- * since this class inherits from the search_base_type_c.
- * However, in this case we don't want it to follow
- * the structs as this search_varfb_instance_type_c does.
- * We therefore have to create a new search_base_type_c
- * instance to search through this type without going
- * through the structs...
- */
- return base_type(symbol->structure_type_name);
- }
-
- /* now search the structure declaration */
- current_structelement_name = var_name;
- /* recursively find out the data type of var_name... */
- return symbol->structure_type_name->accept(*this);
- }
-
-/* helper symbol for structure_declaration */
-/* structure_declaration: STRUCT structure_element_declaration_list END_STRUCT */
-/* structure_element_declaration_list structure_element_declaration ';' */
- void *visit(structure_element_declaration_list_c *symbol) {return visit_list(symbol);}
-
-/* structure_element_name ':' spec_init */
- void *visit(structure_element_declaration_c *symbol) {
- if (NULL == current_structelement_name) ERROR;
-
- if (compare_identifiers(symbol->structure_element_name, current_structelement_name) == 0)
- return symbol->spec_init->accept(*this);
-
- return NULL;
- }
-
-/* helper symbol for structure_initialization */
-/* structure_initialization: '(' structure_element_initialization_list ')' */
-/* structure_element_initialization_list ',' structure_element_initialization */
- void *visit(structure_element_initialization_list_c *symbol) {ERROR; return NULL;} /* should never get called... */
-/* structure_element_name ASSIGN value */
- void *visit(structure_element_initialization_c *symbol) {ERROR; return NULL;} /* should never get called... */
-
-
-
-/**************************************/
-/* B.1.5 - Program organization units */
-/**************************************/
-/*****************************/
-/* B 1.5.2 - Function Blocks */
-/*****************************/
-/* FUNCTION_BLOCK derived_function_block_name io_OR_other_var_declarations function_block_body END_FUNCTION_BLOCK */
-// SYM_REF4(function_block_declaration_c, fblock_name, var_declarations, fblock_body, unused)
- void *visit(function_block_declaration_c *symbol) {
- /* make sure that we have decomposed all strcuture elements of the variable name */
-
- symbol_c *var_name = decompose_var_instance_name->next_part();
- if (NULL == var_name) {
- /* this is it... !
- * No need to look any further...
- * Note also that, unlike for the struct types, a function block may
- * not be defined based on another (i.e. no inheritance is allowed),
- * so this function block is already the most base type.
- * We simply return it.
- */
- return (void *)symbol;
- }
-
- /* now search the function block declaration for the variable... */
- search_var_instance_decl_c search_decl(symbol);
- symbol_c *var_decl = search_decl.get_decl(var_name);
- if (NULL == var_decl) {
- /* variable instance declaration not found! */
- return NULL;
- }
-
- /* We have found the declaration.
- * Should we look any further?
- */
- var_name = decompose_var_instance_name->next_part();
- if (NULL == var_name) {
- /* this is it... ! */
- return base_type(var_decl);
- }
-
- current_structelement_name = var_name;
- /* recursively find out the data type of var_name... */
- return symbol->var_declarations->accept(*this);
- }
-
-};
-
-
-
-
-