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/*
* matiec - a compiler for the programming languages defined in IEC 61131-3
*
* Copyright (C) 2003-2011 Mario de Sousa (msousa@fe.up.pt)
* Copyright (C) 2007-2011 Laurent Bessard and Edouard Tisserant
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 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.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*
* This code is made available on the understanding that it will not be
* used in safety-critical situations without a full and competent review.
*/
/*
* A generic symbol table.
*
* This is used to create symbol tables such as a list of
* variables currently in scope, etc...
* Note that the list of previously defined funstions uses the
* dsymtable_c instead, as it requires the table to store duplicate values.
*/
#include <iostream>
#include "symtable.hh"
#include "../main.hh" // required for ERROR() and ERROR_MSG() macros.
template<typename value_type>
symtable_c<value_type>::symtable_c(void) {inner_scope = NULL;}
/* clear all entries... */
template<typename value_type>
void symtable_c<value_type>::clear(void) {
_base.clear();
}
/* create new inner scope */
template<typename value_type>
void symtable_c<value_type>::push(void) {
if (inner_scope != NULL) {
inner_scope->push();
} else {
inner_scope = new symtable_c();
}
}
/* clear most inner scope */
/* returns 1 if this is the inner most scope */
/* 0 otherwise */
template<typename value_type>
int symtable_c<value_type>::pop(void) {
if (inner_scope != NULL) {
if (inner_scope->pop() == 1) {
delete inner_scope;
inner_scope = NULL;
}
return 0;
} else {
_base.clear();
return 1;
}
}
template<typename value_type>
void symtable_c<value_type>::set(const symbol_c *symbol, value_t new_value) {
if (inner_scope != NULL) {
inner_scope->set(symbol, new_value);
return;
}
const token_c *name = dynamic_cast<const token_c *>(symbol);
if (name == NULL)
ERROR;
set(name->value, new_value);
}
template<typename value_type>
void symtable_c<value_type>::set(const char *identifier_str, value_t new_value) {
if (inner_scope != NULL) {
inner_scope->set(identifier_str, new_value);
return;
}
// std::cout << "set_identifier(" << identifier_str << "): \n";
iterator i = _base.find(identifier_str);
if (i == _base.end())
/* identifier not already in map! */
ERROR;
_base[identifier_str] = new_value;
}
template<typename value_type>
void symtable_c<value_type>::insert(const char *identifier_str, value_t new_value) {
if (inner_scope != NULL) {
inner_scope->insert(identifier_str, new_value);
return;
}
// std::cout << "store_identifier(" << identifier_str << "): \n";
iterator i = _base.find(identifier_str);
if ((i != _base.end()) && (i->second != new_value)) {ERROR;} /* error inserting new identifier: identifier already in map associated to a different value */
if ((i != _base.end()) && (i->second == new_value)) {return;} /* identifier already in map associated with the same value */
std::pair<const char *, value_t> new_element(identifier_str, new_value);
std::pair<iterator, bool> res = _base.insert(new_element);
if (!res.second) {ERROR;} /* unknown error inserting new identifier */
}
template<typename value_type>
void symtable_c<value_type>::insert(const symbol_c *symbol, value_t new_value) {
/*
// not required...
if (inner_scope != NULL) {
inner_scope->insert(symbol, new_value);
return;
}
*/
const token_c *name = dynamic_cast<const token_c *>(symbol);
if (name == NULL)
ERROR;
insert(name->value, new_value);
}
template<typename value_type>
int symtable_c<value_type>::count(const char *identifier_str) {return _base.count(identifier_str)+((inner_scope == NULL)?0:inner_scope->count(identifier_str));}
template<typename value_type>
int symtable_c<value_type>::count(const std::string identifier_str) {return _base.count(identifier_str)+((inner_scope == NULL)?0:inner_scope->count(identifier_str));}
// in the operator[] we delegate to find(), since that method will also search in the inner scopes!
template<typename value_type>
typename symtable_c<value_type>::value_t& symtable_c<value_type>::operator[] (const char *identifier_str) {iterator i = find(identifier_str); return (i!=end())?i->second:_base[identifier_str];}
template<typename value_type>
typename symtable_c<value_type>::value_t& symtable_c<value_type>::operator[] (const std::string identifier_str) {iterator i = find(identifier_str); return (i!=end())?i->second:_base[identifier_str];}
template<typename value_type>
typename symtable_c<value_type>::iterator symtable_c<value_type>::end (void) {return _base.end ();}
template<typename value_type>
typename symtable_c<value_type>::iterator symtable_c<value_type>::begin(void) {return _base.begin();}
/* returns end() if not found! */
template<typename value_type>
typename symtable_c<value_type>::iterator symtable_c<value_type>::find(const char *identifier_str) {
iterator i;
if ((inner_scope != NULL) && ((i = inner_scope->find(identifier_str)) != inner_scope->end())) // NOTE: must use the end() value of the inner scope!
return i; // found in the lower level
/* if no lower level, or not found in lower level... */
return _base.find(identifier_str);
}
template<typename value_type>
typename symtable_c<value_type>::iterator symtable_c<value_type>::find(const std::string identifier_str) {
iterator i;
if ((inner_scope != NULL) && ((i = inner_scope->find(identifier_str)) != inner_scope->end())) // NOTE: must use the end() value of the inner scope!
return i; // found in the lower level
/* if no lower level, or not found in lower level... */
return _base.find(identifier_str);
}
template<typename value_type>
typename symtable_c<value_type>::iterator symtable_c<value_type>::find(const symbol_c *symbol) {
const token_c *name = dynamic_cast<const token_c *>(symbol);
if (name == NULL)
ERROR;
return find(name->value);
}
/* debuging function... */
template<typename value_type>
void symtable_c<value_type>::print(void) {
for(iterator i = _base.begin();
i != _base.end();
i++)
std::cout << i->second << ":" << i->first << "\n";
std::cout << "=====================\n";
if (inner_scope != NULL) {
inner_scope->print();
}
}