Added some comments. Fixed some accesses to potential NULL pointers.
/*
* (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)
*
*/
/*
* Definition of the Abstract Syntax data structure components
*/
#include <stdio.h>
#include <stdlib.h> /* required for exit() */
#include <string.h>
#include "absyntax.hh"
//#include "../stage1_2/iec.hh" /* required for BOGUS_TOKEN_ID, etc... */
#include "visitor.hh"
#define ABORT(str) {printf("ERROR: %s\n", str); exit(0);}
symbol_c *tree_root = NULL;
/* The base class of all symbols */
symbol_c::symbol_c(void) {
lineno = 0;
}
symbol_c::symbol_c(long lineno) {
this->lineno = lineno;
}
token_c::token_c(const char *value) {
this->value = value;
// printf("New token: %s\n", value);
}
list_c::list_c(void) {
n = 0;
elements = NULL;
}
list_c::list_c(symbol_c *elem) {
n = 0;
elements = NULL;
add_element(elem);
}
/* insert a new element */
void list_c::add_element(symbol_c *elem) {
//printf("list_c::add_element()\n");
n++;
elements = (symbol_c **)realloc(elements, n * sizeof(symbol_c *));
if (elements == NULL)
ABORT("Out of memory");
elements[n - 1] = elem;
}
#define SYM_LIST(class_name_c) \
void *class_name_c::accept(visitor_c &visitor) {return visitor.visit(this);}
#define SYM_TOKEN(class_name_c) \
class_name_c::class_name_c(const char *value): token_c(value) {} \
void *class_name_c::accept(visitor_c &visitor) {return visitor.visit(this);}
#define SYM_REF0(class_name_c) \
void *class_name_c::accept(visitor_c &visitor) {return visitor.visit(this);}
#define SYM_REF2(class_name_c, ref1, ref2) \
class_name_c::class_name_c(symbol_c *ref1, \
symbol_c *ref2) { \
this->ref1 = ref1; \
this->ref2 = ref2; \
} \
void *class_name_c::accept(visitor_c &visitor) {return visitor.visit(this);}
#define SYM_REF4(class_name_c, ref1, ref2, ref3, ref4) \
class_name_c::class_name_c(symbol_c *ref1, \
symbol_c *ref2, \
symbol_c *ref3, \
symbol_c *ref4) { \
this->ref1 = ref1; \
this->ref2 = ref2; \
this->ref3 = ref3; \
this->ref4 = ref4; \
} \
void *class_name_c::accept(visitor_c &visitor) {return visitor.visit(this);}
#define SYM_REF6(class_name_c, ref1, ref2, ref3, ref4, ref5, ref6) \
class_name_c::class_name_c(symbol_c *ref1, \
symbol_c *ref2, \
symbol_c *ref3, \
symbol_c *ref4, \
symbol_c *ref5, \
symbol_c *ref6) { \
this->ref1 = ref1; \
this->ref2 = ref2; \
this->ref3 = ref3; \
this->ref4 = ref4; \
this->ref5 = ref5; \
this->ref6 = ref6; \
} \
void *class_name_c::accept(visitor_c &visitor) {return visitor.visit(this);}
#include "absyntax.def"
#undef SYM_LIST
#undef SYM_TOKEN
#undef SYM_TOKEN
#undef SYM_REF0
#undef SYM_REF2
#undef SYM_REF4
#undef SYM_REF6