--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/stage4/generate_cc/search_var_instance_decl.cc Wed Jan 31 15:32:38 2007 +0100
@@ -0,0 +1,304 @@
+/*
+ * (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 specific variable instance, including
+ * function block instances.
+ * A reference to the relevant variable declaration is returned.
+ * The variable instance may NOT be a member of a structure of a memeber
+ * of a structure of an element of an array of ...
+ *
+ * example:
+ * window.points[1].coordinate.x
+ * window.points[1].colour
+ * etc... ARE NOT ALLOWED!
+ *
+ * This class must only be passed the name of the variable that will appear
+ * in the variable declaration. In the above examples, this would be
+ * 'window' !!
+ *
+ *
+ * If you need to pass a complete name of a variable instance (such as
+ * 'window.points[1].coordinate.x') use the search_varfb_instance_type_c instead!
+ */
+/* Note that current_type_decl that this class returns may reference the
+ * name of a type, or the type declaration itself!
+ * For an example of the first, consider a variable declared as ...
+ * x : AAA;
+ * where the AAA type is previously declared as whatever.
+ * For an example of the second, consider a variable declared as ...
+ * x : array of int [10]; ----> is allowed
+ *
+ * If it is the first, we will return a reference to the name, if the second
+ * we return a reference to the declaration!!
+ */
+class search_var_instance_decl_c: public search_visitor_c {
+
+ private:
+ symbol_c *search_scope;
+ symbol_c *search_name;
+ symbol_c *current_type_decl;
+
+ public:
+ search_var_instance_decl_c(symbol_c *search_scope) {
+ this->search_scope = search_scope;
+ this->search_name = NULL;
+ this->current_type_decl = NULL;
+ }
+
+ symbol_c *get_decl(symbol_c *variable_instance_name) {
+ this->search_name = variable_instance_name;
+ return (symbol_c *)search_scope->accept(*this);
+ }
+
+ public:
+/***************************/
+/* B 0 - Programming Model */
+/***************************/
+ void *visit(library_c *symbol) {
+ /* we do not want to search multiple declaration scopes,
+ * so we do not visit all the functions, fucntion blocks, etc...
+ */
+ return NULL;
+ }
+
+
+
+/******************************************/
+/* B 1.4.3 - Declaration & Initialisation */
+/******************************************/
+/* edge -> The F_EDGE or R_EDGE directive */
+// SYM_REF2(edge_declaration_c, edge, var1_list)
+// TODO
+
+/* var1_list is one of the following...
+ * simple_spec_init_c *
+ * subrange_spec_init_c *
+ * enumerated_spec_init_c *
+ */
+// SYM_REF2(var1_init_decl_c, var1_list, spec_init)
+ void *visit(var1_init_decl_c *symbol) {
+ current_type_decl = symbol->spec_init;
+ return symbol->var1_list->accept(*this);
+ }
+
+/* var1_list ',' variable_name */
+// SYM_LIST(var1_list_c)
+ void *visit(var1_list_c *symbol) {
+ list_c *list = symbol;
+ for(int i = 0; i < list->n; i++) {
+ if (compare_identifiers(list->elements[i], search_name) == 0)
+ /* by now, current_type_decl should be != NULL */
+ return current_type_decl;
+ }
+ return NULL;
+ }
+
+/* name_list ':' function_block_type_name ASSIGN structure_initialization */
+/* structure_initialization -> may be NULL ! */
+ void *visit(fb_name_decl_c *symbol) {
+ current_type_decl = symbol->function_block_type_name;
+ return symbol->fb_name_list->accept(*this);
+ }
+
+/* name_list ',' fb_name */
+ void *visit(fb_name_list_c *symbol) {
+ list_c *list = symbol;
+ for(int i = 0; i < list->n; i++) {
+ if (compare_identifiers(list->elements[i], search_name) == 0)
+ /* by now, current_fb_declaration should be != NULL */
+ return current_type_decl;
+ }
+ return NULL;
+ }
+
+/* var1_list ':' array_spec_init */
+// SYM_REF2(array_var_init_decl_c, var1_list, array_spec_init)
+ void *visit(array_var_init_decl_c *symbol) {
+ current_type_decl = symbol->array_spec_init;
+ return symbol->var1_list->accept(*this);
+ }
+
+/* var1_list ':' initialized_structure */
+// SYM_REF2(structured_var_init_decl_c, var1_list, initialized_structure)
+ void *visit(structured_var_init_decl_c *symbol) {
+ current_type_decl = symbol->initialized_structure;
+ return symbol->var1_list->accept(*this);
+ }
+
+/* var1_list ':' array_specification */
+// SYM_REF2(array_var_declaration_c, var1_list, array_specification)
+ void *visit(array_var_declaration_c *symbol) {
+ current_type_decl = symbol->array_specification;
+ return symbol->var1_list->accept(*this);
+ }
+
+/* var1_list ':' structure_type_name */
+// SYM_REF2(structured_var_declaration_c, var1_list, structure_type_name)
+ void *visit(structured_var_declaration_c *symbol) {
+ current_type_decl = symbol->structure_type_name;
+ return symbol->var1_list->accept(*this);
+ }
+
+/* [variable_name] location ':' located_var_spec_init */
+/* variable_name -> may be NULL ! */
+// SYM_REF4(located_var_decl_c, variable_name, location, located_var_spec_init, unused)
+// TODO!!
+
+/* global_var_name ':' (simple_specification|subrange_specification|enumerated_specification|array_specification|prev_declared_structure_type_name|function_block_type_name */
+// SYM_REF2(external_declaration_c, global_var_name, specification)
+ void *visit(external_declaration_c *symbol) {
+ if (compare_identifiers(symbol->global_var_name, search_name) == 0)
+ return symbol->specification;
+ return NULL;
+ }
+
+/*| global_var_spec ':' [located_var_spec_init|function_block_type_name] */
+/* type_specification ->may be NULL ! */
+// SYM_REF2(global_var_decl_c, global_var_spec, type_specification)
+// TODO!!
+
+/*| global_var_name location */
+// SYM_REF2(global_var_spec_c, global_var_name, location)
+// TODO!!
+
+/* AT direct_variable */
+// SYM_REF2(location_c, direct_variable, unused)
+// TODO!!
+
+/*| global_var_list ',' global_var_name */
+// SYM_LIST(global_var_list_c)
+// TODO!!
+
+/* var1_list ':' single_byte_string_spec */
+// SYM_REF2(single_byte_string_var_declaration_c, var1_list, single_byte_string_spec)
+ void *visit(single_byte_string_var_declaration_c *symbol) {
+ current_type_decl = symbol->single_byte_string_spec;
+ return symbol->var1_list->accept(*this);
+ }
+
+/* STRING ['[' integer ']'] [ASSIGN single_byte_character_string] */
+/* integer ->may be NULL ! */
+/* single_byte_character_string ->may be NULL ! */
+// SYM_REF2(single_byte_string_spec_c, integer, single_byte_character_string)
+// TODO!!
+
+/* var1_list ':' double_byte_string_spec */
+// SYM_REF2(double_byte_string_var_declaration_c, var1_list, double_byte_string_spec)
+ void *visit(double_byte_string_var_declaration_c *symbol) {
+ current_type_decl = symbol->double_byte_string_spec;
+ return symbol->var1_list->accept(*this);
+ }
+
+/* WSTRING ['[' integer ']'] [ASSIGN double_byte_character_string] */
+/* integer ->may be NULL ! */
+/* double_byte_character_string ->may be NULL ! */
+// SYM_REF2(double_byte_string_spec_c, integer, double_byte_character_string)
+// TODO!!
+
+/* variable_name incompl_location ':' var_spec */
+// SYM_REF4(incompl_located_var_decl_c, variable_name, incompl_location, var_spec, unused)
+// TODO!!
+
+/* AT incompl_location_token */
+// SYM_TOKEN(incompl_location_c)
+// TODO!!
+
+
+/**************************************/
+/* B.1.5 - Program organization units */
+/**************************************/
+/***********************/
+/* B 1.5.1 - Functions */
+/***********************/
+// SYM_REF4(function_declaration_c, derived_function_name, type_name, var_declarations_list, function_body)
+ void *visit(function_declaration_c *symbol) {
+ /* functions have a variable named after themselves, to store
+ * the variable that will be returned!!
+ */
+ if (compare_identifiers(symbol->derived_function_name, search_name) == 0)
+ return symbol->type_name;
+
+ /* no need to search through all the body, so we only
+ * visit the variable declarations...!
+ */
+ return symbol->var_declarations_list->accept(*this);
+ }
+
+/*****************************/
+/* B 1.5.2 - Function Blocks */
+/*****************************/
+ void *visit(function_block_declaration_c *symbol) {
+ /* no need to search through all the body, so we only
+ * visit the variable declarations...!
+ */
+ return symbol->var_declarations->accept(*this);
+ }
+
+/**********************/
+/* B 1.5.3 - Programs */
+/**********************/
+ void *visit(program_declaration_c *symbol) {
+ /* no need to search through all the body, so we only
+ * visit the variable declarations...!
+ */
+ return symbol->var_declarations->accept(*this);
+ }
+
+
+#if 0
+/*********************/
+/* B 1.4 - Variables */
+/*********************/
+SYM_REF2(symbolic_variable_c, var_name, unused)
+
+/********************************************/
+/* B.1.4.1 Directly Represented Variables */
+/********************************************/
+SYM_TOKEN(direct_variable_c)
+
+/*************************************/
+/* B.1.4.2 Multi-element Variables */
+/*************************************/
+/* subscripted_variable '[' subscript_list ']' */
+SYM_REF2(array_variable_c, subscripted_variable, subscript_list)
+
+/* subscript_list ',' subscript */
+SYM_LIST(subscript_list_c)
+
+/* record_variable '.' field_selector */
+/* WARNING: input and/or output variables of function blocks
+ * may be accessed as fields of a tructured variable!
+ * Code handling a structured_variable_c must take
+ * this into account!
+ */
+SYM_REF2(structured_variable_c, record_variable, field_selector)
+
+
+#endif
+};
+
+
+
+
+