laurent@347: /*
laurent@347: * matiec - a compiler for the programming languages defined in IEC 61131-3
laurent@347: *
laurent@347: * Copyright (C) 2003-2011 Mario de Sousa (msousa@fe.up.pt)
laurent@347: * Copyright (C) 2007-2011 Laurent Bessard and Edouard Tisserant
laurent@347: *
laurent@347: * This program is free software: you can redistribute it and/or modify
laurent@347: * it under the terms of the GNU General Public License as published by
laurent@347: * the Free Software Foundation, either version 3 of the License, or
laurent@347: * (at your option) any later version.
laurent@347: *
laurent@347: * This program is distributed in the hope that it will be useful,
laurent@347: * but WITHOUT ANY WARRANTY; without even the implied warranty of
laurent@347: * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
laurent@347: * GNU General Public License for more details.
laurent@347: *
laurent@347: * You should have received a copy of the GNU General Public License
laurent@347: * along with this program. If not, see .
laurent@347: *
laurent@347: *
laurent@347: * This code is made available on the understanding that it will not be
laurent@347: * used in safety-critical situations without a full and competent review.
laurent@347: */
laurent@347:
laurent@347: /*
laurent@347: * An IEC 61131-3 compiler.
laurent@347: *
laurent@347: * Based on the
laurent@347: * FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)
laurent@347: *
laurent@347: */
laurent@347:
laurent@347:
laurent@347: /*
laurent@347: * Case element iterator.
laurent@347: * Iterate through the elements of a case list.
laurent@347: *
laurent@347: * This is part of the 4th stage that generates
laurent@347: * a c++ source program equivalent to the IL and ST
laurent@347: * code.
laurent@347: */
laurent@347:
laurent@347: /* Given a case_list_c and a type of element, iterate through
laurent@347: * each element, returning the symbol of each element if from
laurent@347: * the good type...case_element_iterator_c
laurent@347: */
laurent@347:
laurent@347:
laurent@347:
laurent@347:
laurent@347: #include "case_element_iterator.hh"
msousa@596: #include "../main.hh" // required for ERROR() and ERROR_MSG() macros.
laurent@347:
laurent@347:
laurent@347: //#define DEBUG
laurent@347: #ifdef DEBUG
laurent@347: #define TRACE(classname) printf("\n____%s____\n",classname);
laurent@347: #else
laurent@347: #define TRACE(classname)
laurent@347: #endif
laurent@347:
laurent@347:
laurent@347:
laurent@347:
laurent@347: void* case_element_iterator_c::handle_case_element(symbol_c *case_element) {
laurent@347: if (current_case_element == case_element) {
laurent@347: current_case_element = NULL;
laurent@347: }
laurent@347: else if (current_case_element == NULL) {
laurent@347: current_case_element = case_element;
laurent@347: return case_element;
laurent@347: }
laurent@347:
laurent@347: /* Not found! */
laurent@347: return NULL;
laurent@347: }
laurent@347:
laurent@347: void* case_element_iterator_c::iterate_list(list_c *list) {
laurent@347: void *res;
laurent@347: for (int i = 0; i < list->n; i++) {
laurent@347: res = list->elements[i]->accept(*this);
laurent@347: if (res != NULL)
laurent@347: return res;
laurent@347: }
laurent@347: return NULL;
laurent@347: }
laurent@347:
laurent@347: /* start off at the first case element once again... */
laurent@347: void case_element_iterator_c::reset(void) {
laurent@347: current_case_element = NULL;
laurent@347: }
laurent@347:
laurent@347:
laurent@377: /* initialize the iterator object.
laurent@377: * We must be given a reference to a case_list_c that will be analyzed...
laurent@347: */
laurent@347: case_element_iterator_c::case_element_iterator_c(symbol_c *list, case_element_t element_type) {
laurent@347: /* do some consistency check... */
laurent@347: case_list_c* case_list = dynamic_cast(list);
laurent@347:
laurent@347: if (NULL == case_list) ERROR;
laurent@347:
laurent@377: /* OK. Now initialize this object... */
laurent@347: this->case_list = list;
laurent@347: this->wanted_element_type = element_type;
laurent@347: reset();
laurent@347: }
laurent@347:
laurent@347:
laurent@347:
laurent@347: /* Skip to the next case element of type chosen. After object creation,
laurent@347: * the object references on case element _before_ the first, so
laurent@347: * this function must be called once to get the object to
laurent@347: * reference the first element...
laurent@347: *
laurent@347: * Returns the case element's symbol!
laurent@347: */
laurent@347: symbol_c *case_element_iterator_c::next(void) {
laurent@347: void *res = case_list->accept(*this);
laurent@347: if (res == NULL)
laurent@347: return NULL;
laurent@347:
laurent@347: return current_case_element;
laurent@347: }
laurent@347:
laurent@347: /******************************/
laurent@347: /* B 1.2.1 - Numeric Literals */
laurent@347: /******************************/
laurent@347: void *case_element_iterator_c::visit(integer_c *symbol) {
laurent@347: switch (wanted_element_type) {
laurent@347: case element_single:
laurent@347: return handle_case_element(symbol);
laurent@347: break;
laurent@347: default:
laurent@347: break;
laurent@347: }
laurent@347: return NULL;
laurent@347: }
laurent@347:
laurent@347: void *case_element_iterator_c::visit(neg_integer_c *symbol) {
laurent@347: switch (wanted_element_type) {
laurent@347: case element_single:
laurent@347: return handle_case_element(symbol);
laurent@347: break;
laurent@347: default:
laurent@347: break;
laurent@347: }
laurent@347: return NULL;
laurent@347: }
laurent@347:
laurent@347: /********************************/
laurent@347: /* B 1.3.3 - Derived data types */
laurent@347: /********************************/
laurent@347: /* signed_integer DOTDOT signed_integer */
laurent@347: void *case_element_iterator_c::visit(subrange_c *symbol) {
laurent@347: switch (wanted_element_type) {
laurent@347: case element_subrange:
laurent@347: return handle_case_element(symbol);
laurent@347: break;
laurent@347: default:
laurent@347: break;
laurent@347: }
laurent@347: return NULL;
laurent@347: }
laurent@347:
laurent@347: /* enumerated_type_name '#' identifier */
laurent@347: void *case_element_iterator_c::visit(enumerated_value_c *symbol) {
laurent@347: switch (wanted_element_type) {
laurent@347: case element_single:
laurent@347: return handle_case_element(symbol);
laurent@347: break;
laurent@347: default:
laurent@347: break;
laurent@347: }
laurent@347: return NULL;
laurent@347: }
laurent@347:
laurent@347: /********************************/
laurent@347: /* B 3.2.3 Selection Statements */
laurent@347: /********************************/
laurent@347: void *case_element_iterator_c::visit(case_list_c *symbol) {
laurent@347: return iterate_list(symbol);
laurent@347: }
laurent@347: