/*
* (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)
*
*/
/*
* VISITOR.CC
*
* Three base implementations of the visitor interface,
* that may be later extended to execute a particular algorithm.
*
* The null (class null_visitor_c) does nothing.
*
* The iterator (class iterator_visitor_c) iterates through
* every object in the syntax tree.
*
* The search class (class search_visitor_c) iterates through
* every object, until one returns a value != NULL.
*/
#include <unistd.h>
#include <stdio.h> /* required for NULL */
#include "visitor.hh"
#include <iostream>
/******************/
/* visitor_c */
/******************/
visitor_c::~visitor_c(void) {return;}
/******************/
/* null_visitor_c */
/******************/
null_visitor_c::~null_visitor_c(void) {return;}
#define SYM_LIST(class_name_c) \
void *null_visitor_c::visit(class_name_c *symbol) {return NULL;}
#define SYM_TOKEN(class_name_c) \
void *null_visitor_c::visit(class_name_c *symbol) {return NULL;}
#define SYM_REF0(class_name_c) \
void *null_visitor_c::visit(class_name_c *symbol) {return NULL;}
#define SYM_REF2(class_name_c, ref1, ref2) \
void *null_visitor_c::visit(class_name_c *symbol) {return NULL;}
#define SYM_REF4(class_name_c, ref1, ref2, ref3, ref4) \
void *null_visitor_c::visit(class_name_c *symbol) {return NULL;}
#define SYM_REF6(class_name_c, ref1, ref2, ref3, ref4, ref5, ref6) \
void *null_visitor_c::visit(class_name_c *symbol) {return NULL;}
#include "absyntax.def"
#undef SYM_LIST
#undef SYM_TOKEN
#undef SYM_REF0
#undef SYM_REF2
#undef SYM_REF4
#undef SYM_REF6
/**********************/
/* iterator_visitor_c */
/**********************/
iterator_visitor_c::~iterator_visitor_c(void) {return;}
void *iterator_visitor_c::visit_list(list_c *list) {
for(int i = 0; i < list->n; i++) {
list->elements[i]->accept(*this);
}
return NULL;
}
#define SYM_LIST(class_name_c) \
void *iterator_visitor_c::visit(class_name_c *symbol) {return visit_list(symbol);}
#define SYM_TOKEN(class_name_c) \
void *iterator_visitor_c::visit(class_name_c *symbol) {return NULL;}
#define SYM_REF0(class_name_c) \
void *iterator_visitor_c::visit(class_name_c *symbol) {return NULL;}
#define SYM_REF2(class_name_c, ref1, ref2) \
void *iterator_visitor_c::visit(class_name_c *symbol) { \
if (symbol->ref1!=NULL) symbol->ref1->accept(*this); \
if (symbol->ref2!=NULL) symbol->ref2->accept(*this); \
return NULL; \
}
#define SYM_REF4(class_name_c, ref1, ref2, ref3, ref4) \
void *iterator_visitor_c::visit(class_name_c *symbol) { \
if (symbol->ref1) symbol->ref1->accept(*this); \
if (symbol->ref2) symbol->ref2->accept(*this); \
if (symbol->ref3) symbol->ref3->accept(*this); \
if (symbol->ref4) symbol->ref4->accept(*this); \
return NULL; \
}
#define SYM_REF6(class_name_c, ref1, ref2, ref3, ref4, ref5, ref6) \
void *iterator_visitor_c::visit(class_name_c *symbol) { \
if (symbol->ref1) symbol->ref1->accept(*this); \
if (symbol->ref2) symbol->ref2->accept(*this); \
if (symbol->ref3) symbol->ref3->accept(*this); \
if (symbol->ref4) symbol->ref4->accept(*this); \
if (symbol->ref5) symbol->ref5->accept(*this); \
if (symbol->ref6) symbol->ref6->accept(*this); \
return NULL; \
}
#include "absyntax.def"
#undef SYM_LIST
#undef SYM_TOKEN
#undef SYM_REF0
#undef SYM_REF2
#undef SYM_REF4
#undef SYM_REF6
/********************/
/* search_visitor_c */
/********************/
search_visitor_c::~search_visitor_c(void) {return;}
void *search_visitor_c::visit_list(list_c *list) {
for(int i = 0; i < list->n; i++) {
void *res = list->elements[i]->accept(*this);
if (res != NULL)
return res;
}
return NULL;
}
#define SYM_LIST(class_name_c) \
void *search_visitor_c::visit(class_name_c *symbol) {return visit_list(symbol);}
#define SYM_TOKEN(class_name_c) \
void *search_visitor_c::visit(class_name_c *symbol) {return NULL;}
#define SYM_REF0(class_name_c) \
void *search_visitor_c::visit(class_name_c *symbol) {return NULL;}
#define SYM_REF2(class_name_c, ref1, ref2) \
void *search_visitor_c::visit(class_name_c *symbol) { \
void *res = NULL; \
if (symbol->ref1) res = symbol->ref1->accept(*this); \
if (res != NULL) return res; \
if (symbol->ref2) return symbol->ref2->accept(*this); \
return NULL; \
}
#define SYM_REF4(class_name_c, ref1, ref2, ref3, ref4) \
void *search_visitor_c::visit(class_name_c *symbol) { \
void *res = NULL; \
if (symbol->ref1) res = symbol->ref1->accept(*this); \
if (res != NULL) return res; \
if (symbol->ref2) res = symbol->ref2->accept(*this); \
if (res != NULL) return res; \
if (symbol->ref3) res = symbol->ref3->accept(*this); \
if (res != NULL) return res; \
if (symbol->ref4) return symbol->ref4->accept(*this); \
return NULL; \
}
#define SYM_REF6(class_name_c, ref1, ref2, ref3, ref4, ref5, ref6) \
void *search_visitor_c::visit(class_name_c *symbol) { \
void *res = NULL; \
if (symbol->ref1) res = symbol->ref1->accept(*this); \
if (res != NULL) return res; \
if (symbol->ref2) res = symbol->ref2->accept(*this); \
if (res != NULL) return res; \
if (symbol->ref3) res = symbol->ref3->accept(*this); \
if (res != NULL) return res; \
if (symbol->ref4) res = symbol->ref4->accept(*this); \
if (res != NULL) return res; \
if (symbol->ref5) res = symbol->ref5->accept(*this); \
if (res != NULL) return res; \
if (symbol->ref6) return symbol->ref6->accept(*this); \
return NULL; \
}
#include "absyntax.def"
#undef SYM_LIST
#undef SYM_TOKEN
#undef SYM_REF0
#undef SYM_REF2
#undef SYM_REF4
#undef SYM_REF6