solidity/Types.cpp

/*
	This file is part of cpp-ethereum.

	cpp-ethereum 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.

	cpp-ethereum 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 cpp-ethereum.  If not, see <http://www.gnu.org/licenses/>.
*/
/**
 * @author Christian <c@ethdev.com>
 * @date 2014
 * Solidity data types
 */

#include <libsolidity/Types.h>
#include <libsolidity/AST.h>

namespace dev {
namespace solidity {

ptr<Type> Type::fromElementaryTypeName(Token::Value _typeToken)
{
	if (Token::INT <= _typeToken && _typeToken <= Token::HASH256) {
		int offset = _typeToken - Token::INT;
		int bits = offset % 5;
		if (bits == 0)
			bits = 256;
		else
			bits = (1 << (bits - 1)) * 32;
		int modifier = offset / 5;
		return std::make_shared<IntegerType>(bits,
											 modifier == 0 ? IntegerType::Modifier::SIGNED :
											 modifier == 1 ? IntegerType::Modifier::UNSIGNED :
															 IntegerType::Modifier::HASH);
	} else if (_typeToken == Token::ADDRESS) {
		return std::make_shared<IntegerType>(0, IntegerType::Modifier::ADDRESS);
	} else if (_typeToken == Token::BOOL) {
		return std::make_shared<BoolType>();
	} else {
		BOOST_ASSERT(false);
		// @todo add other tyes
	}
}

ptr<Type> Type::fromUserDefinedTypeName(const UserDefinedTypeName& _typeName)
{
	return std::make_shared<StructType>(*_typeName.getReferencedStruct());
}

ptr<Type> Type::fromMapping(const Mapping&)
{
	BOOST_ASSERT(false); //@todo not yet implemented
	return ptr<Type>();
}

ptr<Type> Type::forLiteral(const Literal& _literal)
{
	switch (_literal.getToken()) {
	case Token::TRUE_LITERAL:
	case Token::FALSE_LITERAL:
		return std::make_shared<BoolType>();
	case Token::NUMBER:
		return IntegerType::smallestTypeForLiteral(_literal.getValue());
	case Token::STRING_LITERAL:
		return ptr<Type>(); // @todo
	default:
		return ptr<Type>();
	}
}

ptr<IntegerType> IntegerType::smallestTypeForLiteral(const std::string&)
{
	//@todo
	return std::make_shared<IntegerType>(256, Modifier::UNSIGNED);
}

IntegerType::IntegerType(int _bits, IntegerType::Modifier _modifier)
	: m_bits(_bits), m_modifier(_modifier)
{
	BOOST_ASSERT(_bits > 0 && _bits <= 256 && _bits % 8 == 0);
	if (isAddress())
		_bits = 160;
}

bool IntegerType::isImplicitlyConvertibleTo(Type const& _convertTo) const
{
	if (_convertTo.getCategory() != Category::INTEGER)
		return false;
	IntegerType const& convertTo = dynamic_cast<IntegerType const&>(_convertTo);
	if (convertTo.m_bits < m_bits)
		return false;
	if (isAddress())
		return convertTo.isAddress();
	else if (isHash())
		return convertTo.isHash();
	else if (isSigned())
		return convertTo.isSigned();
	else
		return !convertTo.isSigned() || convertTo.m_bits > m_bits;
}

bool IntegerType::isExplicitlyConvertibleTo(const Type& _convertTo) const
{
	return _convertTo.getCategory() == Category::INTEGER;
}

bool IntegerType::acceptsBinaryOperator(Token::Value _operator) const
{
	if (isAddress()) {
		return Token::IsCompareOp(_operator);
	} else if (isHash()) {
		return Token::IsCompareOp(_operator) || Token::IsBitOp(_operator);
	} else {
		return true;
	}
}

bool IntegerType::acceptsUnaryOperator(Token::Value _operator) const
{
	return _operator == Token::DELETE || (!isAddress() && _operator == Token::BIT_NOT);
}

bool BoolType::isExplicitlyConvertibleTo(const Type& _convertTo) const
{
	// conversion to integer is fine, but not to address
	// this is an example of explicit conversions being not transitive (though implicit should be)
	if (_convertTo.getCategory() == Category::INTEGER) {
		IntegerType const& convertTo = dynamic_cast<IntegerType const&>(_convertTo);
		if (!convertTo.isAddress())
			return true;
	}
	return isImplicitlyConvertibleTo(_convertTo);
}

bool ContractType::isImplicitlyConvertibleTo(const Type& _convertTo) const
{
	if (_convertTo.getCategory() != Category::CONTRACT)
		return false;
	ContractType const& convertTo = dynamic_cast<ContractType const&>(_convertTo);
	return &m_contract == &convertTo.m_contract;
}

bool StructType::isImplicitlyConvertibleTo(const Type& _convertTo) const
{
	if (_convertTo.getCategory() != Category::STRUCT)
		return false;
	StructType const& convertTo = dynamic_cast<StructType const&>(_convertTo);
	return &m_struct == &convertTo.m_struct;
}


} }