solidity/AST.cpp
2014-11-26 15:35:25 +01:00

573 lines
16 KiB
C++

/*
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 abstract syntax tree.
*/
#include <algorithm>
#include <libsolidity/AST.h>
#include <libsolidity/ASTVisitor.h>
#include <libsolidity/Exceptions.h>
using namespace std;
namespace dev
{
namespace solidity
{
void ContractDefinition::accept(ASTVisitor& _visitor)
{
if (_visitor.visit(*this))
{
listAccept(m_definedStructs, _visitor);
listAccept(m_stateVariables, _visitor);
listAccept(m_definedFunctions, _visitor);
}
_visitor.endVisit(*this);
}
void StructDefinition::accept(ASTVisitor& _visitor)
{
if (_visitor.visit(*this))
listAccept(m_members, _visitor);
_visitor.endVisit(*this);
}
void StructDefinition::checkValidityOfMembers()
{
checkMemberTypes();
checkRecursion();
}
void StructDefinition::checkMemberTypes()
{
for (ASTPointer<VariableDeclaration> const& member: getMembers())
if (!member->getType()->canBeStored())
BOOST_THROW_EXCEPTION(member->createTypeError("Type cannot be used in struct."));
}
void StructDefinition::checkRecursion()
{
set<StructDefinition const*> definitionsSeen;
vector<StructDefinition const*> queue = {this};
while (!queue.empty())
{
StructDefinition const* def = queue.back();
queue.pop_back();
if (definitionsSeen.count(def))
BOOST_THROW_EXCEPTION(ParserError() << errinfo_sourceLocation(def->getLocation())
<< errinfo_comment("Recursive struct definition."));
definitionsSeen.insert(def);
for (ASTPointer<VariableDeclaration> const& member: def->getMembers())
if (member->getType()->getCategory() == Type::Category::STRUCT)
{
UserDefinedTypeName const& typeName = dynamic_cast<UserDefinedTypeName&>(*member->getTypeName());
queue.push_back(&dynamic_cast<StructDefinition const&>(*typeName.getReferencedDeclaration()));
}
}
}
void ParameterList::accept(ASTVisitor& _visitor)
{
if (_visitor.visit(*this))
listAccept(m_parameters, _visitor);
_visitor.endVisit(*this);
}
void FunctionDefinition::accept(ASTVisitor& _visitor)
{
if (_visitor.visit(*this))
{
m_parameters->accept(_visitor);
if (m_returnParameters)
m_returnParameters->accept(_visitor);
m_body->accept(_visitor);
}
_visitor.endVisit(*this);
}
void VariableDeclaration::accept(ASTVisitor& _visitor)
{
if (_visitor.visit(*this))
if (m_typeName)
m_typeName->accept(_visitor);
_visitor.endVisit(*this);
}
void TypeName::accept(ASTVisitor& _visitor)
{
_visitor.visit(*this);
_visitor.endVisit(*this);
}
void ElementaryTypeName::accept(ASTVisitor& _visitor)
{
_visitor.visit(*this);
_visitor.endVisit(*this);
}
void UserDefinedTypeName::accept(ASTVisitor& _visitor)
{
_visitor.visit(*this);
_visitor.endVisit(*this);
}
void Mapping::accept(ASTVisitor& _visitor)
{
if (_visitor.visit(*this))
{
m_keyType->accept(_visitor);
m_valueType->accept(_visitor);
}
_visitor.endVisit(*this);
}
void Statement::accept(ASTVisitor& _visitor)
{
_visitor.visit(*this);
_visitor.endVisit(*this);
}
void Block::accept(ASTVisitor& _visitor)
{
if (_visitor.visit(*this))
listAccept(m_statements, _visitor);
_visitor.endVisit(*this);
}
void IfStatement::accept(ASTVisitor& _visitor)
{
if (_visitor.visit(*this))
{
m_condition->accept(_visitor);
m_trueBody->accept(_visitor);
if (m_falseBody)
m_falseBody->accept(_visitor);
}
_visitor.endVisit(*this);
}
void BreakableStatement::accept(ASTVisitor& _visitor)
{
_visitor.visit(*this);
_visitor.endVisit(*this);
}
void WhileStatement::accept(ASTVisitor& _visitor)
{
if (_visitor.visit(*this))
{
m_condition->accept(_visitor);
m_body->accept(_visitor);
}
_visitor.endVisit(*this);
}
void Continue::accept(ASTVisitor& _visitor)
{
_visitor.visit(*this);
_visitor.endVisit(*this);
}
void Break::accept(ASTVisitor& _visitor)
{
_visitor.visit(*this);
_visitor.endVisit(*this);
}
void Return::accept(ASTVisitor& _visitor)
{
if (_visitor.visit(*this))
if (m_expression)
m_expression->accept(_visitor);
_visitor.endVisit(*this);
}
void ExpressionStatement::accept(ASTVisitor& _visitor)
{
if (_visitor.visit(*this))
if (m_expression)
m_expression->accept(_visitor);
_visitor.endVisit(*this);
}
void VariableDefinition::accept(ASTVisitor& _visitor)
{
if (_visitor.visit(*this))
{
m_variable->accept(_visitor);
if (m_value)
m_value->accept(_visitor);
}
_visitor.endVisit(*this);
}
void Assignment::accept(ASTVisitor& _visitor)
{
if (_visitor.visit(*this))
{
m_leftHandSide->accept(_visitor);
m_rightHandSide->accept(_visitor);
}
_visitor.endVisit(*this);
}
void UnaryOperation::accept(ASTVisitor& _visitor)
{
if (_visitor.visit(*this))
m_subExpression->accept(_visitor);
_visitor.endVisit(*this);
}
void BinaryOperation::accept(ASTVisitor& _visitor)
{
if (_visitor.visit(*this))
{
m_left->accept(_visitor);
m_right->accept(_visitor);
}
_visitor.endVisit(*this);
}
void FunctionCall::accept(ASTVisitor& _visitor)
{
if (_visitor.visit(*this))
{
m_expression->accept(_visitor);
listAccept(m_arguments, _visitor);
}
_visitor.endVisit(*this);
}
void MemberAccess::accept(ASTVisitor& _visitor)
{
if (_visitor.visit(*this))
m_expression->accept(_visitor);
_visitor.endVisit(*this);
}
void IndexAccess::accept(ASTVisitor& _visitor)
{
if (_visitor.visit(*this))
{
m_base->accept(_visitor);
m_index->accept(_visitor);
}
_visitor.endVisit(*this);
}
void Identifier::accept(ASTVisitor& _visitor)
{
_visitor.visit(*this);
_visitor.endVisit(*this);
}
void ElementaryTypeNameExpression::accept(ASTVisitor& _visitor)
{
_visitor.visit(*this);
_visitor.endVisit(*this);
}
void Literal::accept(ASTVisitor& _visitor)
{
_visitor.visit(*this);
_visitor.endVisit(*this);
}
TypeError ASTNode::createTypeError(string const& _description) const
{
return TypeError() << errinfo_sourceLocation(getLocation()) << errinfo_comment(_description);
}
vector<FunctionDefinition const*> ContractDefinition::getInterfaceFunctions() const
{
vector<FunctionDefinition const*> exportedFunctions;
for (ASTPointer<FunctionDefinition> const& f: m_definedFunctions)
if (f->isPublic() && f->getName() != getName())
exportedFunctions.push_back(f.get());
auto compareNames = [](FunctionDefinition const* _a, FunctionDefinition const* _b)
{
return _a->getName().compare(_b->getName()) < 0;
};
sort(exportedFunctions.begin(), exportedFunctions.end(), compareNames);
return exportedFunctions;
}
void FunctionDefinition::checkTypeRequirements()
{
for (ASTPointer<VariableDeclaration> const& var: getParameters() + getReturnParameters())
if (!var->getType()->canLiveOutsideStorage())
BOOST_THROW_EXCEPTION(var->createTypeError("Type is required to live outside storage."));
m_body->checkTypeRequirements();
}
void Block::checkTypeRequirements()
{
for (shared_ptr<Statement> const& statement: m_statements)
statement->checkTypeRequirements();
}
void IfStatement::checkTypeRequirements()
{
m_condition->expectType(BoolType());
m_trueBody->checkTypeRequirements();
if (m_falseBody)
m_falseBody->checkTypeRequirements();
}
void WhileStatement::checkTypeRequirements()
{
m_condition->expectType(BoolType());
m_body->checkTypeRequirements();
}
void Return::checkTypeRequirements()
{
if (!m_expression)
return;
if (asserts(m_returnParameters))
BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Return parameters not assigned."));
if (m_returnParameters->getParameters().size() != 1)
BOOST_THROW_EXCEPTION(createTypeError("Different number of arguments in return statement "
"than in returns declaration."));
// this could later be changed such that the paramaters type is an anonymous struct type,
// but for now, we only allow one return parameter
m_expression->expectType(*m_returnParameters->getParameters().front()->getType());
}
void VariableDefinition::checkTypeRequirements()
{
// Variables can be declared without type (with "var"), in which case the first assignment
// sets the type.
// Note that assignments before the first declaration are legal because of the special scoping
// rules inherited from JavaScript.
if (m_value)
{
if (m_variable->getType())
m_value->expectType(*m_variable->getType());
else
{
// no type declared and no previous assignment, infer the type
m_value->checkTypeRequirements();
m_variable->setType(m_value->getType());
}
}
}
void Assignment::checkTypeRequirements()
{
m_leftHandSide->checkTypeRequirements();
m_leftHandSide->requireLValue();
m_rightHandSide->expectType(*m_leftHandSide->getType());
m_type = m_leftHandSide->getType();
if (m_assigmentOperator != Token::ASSIGN)
// compound assignment
if (!m_type->acceptsBinaryOperator(Token::AssignmentToBinaryOp(m_assigmentOperator)))
BOOST_THROW_EXCEPTION(createTypeError("Operator not compatible with type."));
}
void ExpressionStatement::checkTypeRequirements()
{
m_expression->checkTypeRequirements();
}
void Expression::expectType(Type const& _expectedType)
{
checkTypeRequirements();
Type const& type = *getType();
if (!type.isImplicitlyConvertibleTo(_expectedType))
BOOST_THROW_EXCEPTION(createTypeError("Type " + type.toString() +
" not implicitly convertible to expected type "
+ _expectedType.toString() + "."));
}
void Expression::requireLValue()
{
if (!isLvalue())
BOOST_THROW_EXCEPTION(createTypeError("Expression has to be an lvalue."));
m_lvalueRequested = true;
}
void UnaryOperation::checkTypeRequirements()
{
// INC, DEC, ADD, SUB, NOT, BIT_NOT, DELETE
m_subExpression->checkTypeRequirements();
if (m_operator == Token::Value::INC || m_operator == Token::Value::DEC || m_operator == Token::Value::DELETE)
m_subExpression->requireLValue();
m_type = m_subExpression->getType();
if (!m_type->acceptsUnaryOperator(m_operator))
BOOST_THROW_EXCEPTION(createTypeError("Unary operator not compatible with type."));
}
void BinaryOperation::checkTypeRequirements()
{
m_left->checkTypeRequirements();
m_right->checkTypeRequirements();
if (m_right->getType()->isImplicitlyConvertibleTo(*m_left->getType()))
m_commonType = m_left->getType();
else if (m_left->getType()->isImplicitlyConvertibleTo(*m_right->getType()))
m_commonType = m_right->getType();
else
BOOST_THROW_EXCEPTION(createTypeError("No common type found in binary operation: " +
m_left->getType()->toString() + " vs. " +
m_right->getType()->toString()));
if (Token::isCompareOp(m_operator))
m_type = make_shared<BoolType>();
else
{
m_type = m_commonType;
if (!m_commonType->acceptsBinaryOperator(m_operator))
BOOST_THROW_EXCEPTION(createTypeError("Operator " + string(Token::toString(m_operator)) +
" not compatible with type " +
m_commonType->toString()));
}
}
void FunctionCall::checkTypeRequirements()
{
m_expression->checkTypeRequirements();
for (ASTPointer<Expression> const& argument: m_arguments)
argument->checkTypeRequirements();
Type const* expressionType = m_expression->getType().get();
if (isTypeConversion())
{
TypeType const& type = dynamic_cast<TypeType const&>(*expressionType);
//@todo for structs, we have to check the number of arguments to be equal to the
// number of non-mapping members
if (m_arguments.size() != 1)
BOOST_THROW_EXCEPTION(createTypeError("More than one argument for "
"explicit type conersion."));
if (!m_arguments.front()->getType()->isExplicitlyConvertibleTo(*type.getActualType()))
BOOST_THROW_EXCEPTION(createTypeError("Explicit type conversion not allowed."));
m_type = type.getActualType();
}
else
{
//@todo would be nice to create a struct type from the arguments
// and then ask if that is implicitly convertible to the struct represented by the
// function parameters
FunctionType const& functionType = dynamic_cast<FunctionType const&>(*expressionType);
TypePointers const& parameterTypes = functionType.getParameterTypes();
if (parameterTypes.size() != m_arguments.size())
BOOST_THROW_EXCEPTION(createTypeError("Wrong argument count for function call."));
for (size_t i = 0; i < m_arguments.size(); ++i)
if (!m_arguments[i]->getType()->isImplicitlyConvertibleTo(*parameterTypes[i]))
BOOST_THROW_EXCEPTION(createTypeError("Invalid type for argument in function call."));
// @todo actually the return type should be an anonymous struct,
// but we change it to the type of the first return value until we have structs
if (functionType.getReturnParameterTypes().empty())
m_type = make_shared<VoidType>();
else
m_type = functionType.getReturnParameterTypes().front();
}
}
bool FunctionCall::isTypeConversion() const
{
return m_expression->getType()->getCategory() == Type::Category::TYPE;
}
void MemberAccess::checkTypeRequirements()
{
m_expression->checkTypeRequirements();
Type const& type = *m_expression->getType();
m_type = type.getMemberType(*m_memberName);
if (!m_type)
BOOST_THROW_EXCEPTION(createTypeError("Member \"" + *m_memberName + "\" not found in " + type.toString()));
m_isLvalue = (type.getCategory() == Type::Category::STRUCT && m_type->getCategory() != Type::Category::MAPPING);
}
void IndexAccess::checkTypeRequirements()
{
m_base->checkTypeRequirements();
if (m_base->getType()->getCategory() != Type::Category::MAPPING)
BOOST_THROW_EXCEPTION(m_base->createTypeError("Indexed expression has to be a mapping (is " +
m_base->getType()->toString() + ")"));
MappingType const& type = dynamic_cast<MappingType const&>(*m_base->getType());
m_index->expectType(*type.getKeyType());
m_type = type.getValueType();
m_isLvalue = m_type->getCategory() != Type::Category::MAPPING;
}
void Identifier::checkTypeRequirements()
{
if (asserts(m_referencedDeclaration))
BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Identifier not resolved."));
VariableDeclaration* variable = dynamic_cast<VariableDeclaration*>(m_referencedDeclaration);
if (variable)
{
if (!variable->getType())
BOOST_THROW_EXCEPTION(createTypeError("Variable referenced before type could be determined."));
m_type = variable->getType();
m_isLvalue = true;
return;
}
//@todo can we unify these with TypeName::toType()?
StructDefinition* structDef = dynamic_cast<StructDefinition*>(m_referencedDeclaration);
if (structDef)
{
// note that we do not have a struct type here
m_type = make_shared<TypeType>(make_shared<StructType>(*structDef));
return;
}
FunctionDefinition* functionDef = dynamic_cast<FunctionDefinition*>(m_referencedDeclaration);
if (functionDef)
{
// a function reference is not a TypeType, because calling a TypeType converts to the type.
// Calling a function (e.g. function(12), otherContract.function(34)) does not do a type
// conversion.
m_type = make_shared<FunctionType>(*functionDef);
return;
}
ContractDefinition* contractDef = dynamic_cast<ContractDefinition*>(m_referencedDeclaration);
if (contractDef)
{
m_type = make_shared<TypeType>(make_shared<ContractType>(*contractDef));
return;
}
MagicVariableDeclaration* magicVariable = dynamic_cast<MagicVariableDeclaration*>(m_referencedDeclaration);
if (magicVariable)
{
m_type = magicVariable->getType();
return;
}
BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Declaration reference of unknown/forbidden type."));
}
void ElementaryTypeNameExpression::checkTypeRequirements()
{
m_type = make_shared<TypeType>(Type::fromElementaryTypeName(m_typeToken));
}
void Literal::checkTypeRequirements()
{
m_type = Type::forLiteral(*this);
if (!m_type)
BOOST_THROW_EXCEPTION(createTypeError("Literal value too large."));
}
}
}