--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/stage4/generate_c/search_fb_instance_decl.cc	Wed Oct 24 17:39:51 2007 +0200
@@ -0,0 +1,141 @@
+/*
+ * (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)
+ *
+ */
+
+
+/* Returns the function block type declaration
+ * of a specific function block instance.
+ */
+
+
+
+/* Returns the type name of a specific function block
+ * instance. This class will search the variable
+ * declarations inside the scope given to it
+ * searching for the declaration of the function
+ * block instance.
+ *
+ * The class constructor must be given the search scope
+ * (function, function block or program within which
+ * the function block instance was declared).
+ *
+ * This class will search the tree from the root given to the
+ * constructor. Another option would be to build a symbol table,
+ * and search that instead. Building the symbol table would be done
+ * while visiting the variable declaration objects in the parse
+ * tree. Unfortuantely, generate_c_c does not visit these
+ * objects, delegating it to another class. This means that
+ * we would need another specialised class just to build the
+ * symbol table. We might just as well have a specialised class
+ * that searches the tree itself for the relevant info. This
+ * class is exactly that...!
+ */
+class search_fb_instance_decl_c: public search_visitor_c {
+
+  private:
+    symbol_c *search_scope;
+
+    symbol_c *search_name;
+    symbol_c *current_fb_type_name;
+
+  public:
+    search_fb_instance_decl_c(symbol_c *search_scope) {
+      this->search_scope = search_scope;
+      this->current_fb_type_name = NULL;
+    }
+
+    symbol_c *get_type_name(symbol_c *fb_instance_name) {
+      this->search_name = fb_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 */
+/******************************************/
+
+/* name_list ':' function_block_type_name ASSIGN structure_initialization */
+/* structure_initialization -> may be NULL ! */
+    void *visit(fb_name_decl_c *symbol) {
+      current_fb_type_name = 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_fb_type_name;
+      }
+      return NULL;
+    }
+
+/**************************************/
+/* B.1.5 - Program organization units */
+/**************************************/
+/***********************/
+/* B 1.5.1 - Functions */
+/***********************/
+    void *visit(function_declaration_c *symbol) {
+      /* 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);
+    }
+};
+
+
+
+