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Diffstat (limited to 'libsolidity/NameAndTypeResolver.cpp')
| -rw-r--r-- | libsolidity/NameAndTypeResolver.cpp | 530 |
1 files changed, 530 insertions, 0 deletions
diff --git a/libsolidity/NameAndTypeResolver.cpp b/libsolidity/NameAndTypeResolver.cpp new file mode 100644 index 00000000..87f9da7e --- /dev/null +++ b/libsolidity/NameAndTypeResolver.cpp @@ -0,0 +1,530 @@ +/* + 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 + * Parser part that determines the declarations corresponding to names and the types of expressions. + */ + +#include <libsolidity/NameAndTypeResolver.h> +#include <libsolidity/AST.h> +#include <libsolidity/Exceptions.h> + +using namespace std; + +namespace dev +{ +namespace solidity +{ + +NameAndTypeResolver::NameAndTypeResolver(vector<Declaration const*> const& _globals) +{ + for (Declaration const* declaration: _globals) + m_scopes[nullptr].registerDeclaration(*declaration); +} + +void NameAndTypeResolver::registerDeclarations(SourceUnit& _sourceUnit) +{ + // The helper registers all declarations in m_scopes as a side-effect of its construction. + DeclarationRegistrationHelper registrar(m_scopes, _sourceUnit); +} + +void NameAndTypeResolver::resolveNamesAndTypes(ContractDefinition& _contract) +{ + m_currentScope = &m_scopes[nullptr]; + + for (ASTPointer<InheritanceSpecifier> const& baseContract: _contract.getBaseContracts()) + ReferencesResolver resolver(*baseContract, *this, &_contract, nullptr); + + m_currentScope = &m_scopes[&_contract]; + + linearizeBaseContracts(_contract); + std::vector<ContractDefinition const*> properBases( + ++_contract.getLinearizedBaseContracts().begin(), + _contract.getLinearizedBaseContracts().end() + ); + + for (ContractDefinition const* base: properBases) + importInheritedScope(*base); + + for (ASTPointer<StructDefinition> const& structDef: _contract.getDefinedStructs()) + ReferencesResolver resolver(*structDef, *this, &_contract, nullptr); + for (ASTPointer<EnumDefinition> const& enumDef: _contract.getDefinedEnums()) + ReferencesResolver resolver(*enumDef, *this, &_contract, nullptr); + for (ASTPointer<VariableDeclaration> const& variable: _contract.getStateVariables()) + ReferencesResolver resolver(*variable, *this, &_contract, nullptr); + for (ASTPointer<EventDefinition> const& event: _contract.getEvents()) + ReferencesResolver resolver(*event, *this, &_contract, nullptr); + + // these can contain code, only resolve parameters for now + for (ASTPointer<ModifierDefinition> const& modifier: _contract.getFunctionModifiers()) + { + m_currentScope = &m_scopes[modifier.get()]; + ReferencesResolver resolver(*modifier, *this, &_contract, nullptr); + } + for (ASTPointer<FunctionDefinition> const& function: _contract.getDefinedFunctions()) + { + m_currentScope = &m_scopes[function.get()]; + ReferencesResolver referencesResolver(*function, *this, &_contract, + function->getReturnParameterList().get()); + } + + m_currentScope = &m_scopes[&_contract]; + + // now resolve references inside the code + for (ASTPointer<ModifierDefinition> const& modifier: _contract.getFunctionModifiers()) + { + m_currentScope = &m_scopes[modifier.get()]; + ReferencesResolver resolver(*modifier, *this, &_contract, nullptr, true); + } + for (ASTPointer<FunctionDefinition> const& function: _contract.getDefinedFunctions()) + { + m_currentScope = &m_scopes[function.get()]; + ReferencesResolver referencesResolver( + *function, + *this, + &_contract, + function->getReturnParameterList().get(), + true + ); + } +} + +void NameAndTypeResolver::checkTypeRequirements(ContractDefinition& _contract) +{ + for (ASTPointer<StructDefinition> const& structDef: _contract.getDefinedStructs()) + structDef->checkValidityOfMembers(); + _contract.checkTypeRequirements(); +} + +void NameAndTypeResolver::updateDeclaration(Declaration const& _declaration) +{ + m_scopes[nullptr].registerDeclaration(_declaration, false, true); + solAssert(_declaration.getScope() == nullptr, "Updated declaration outside global scope."); +} + +vector<Declaration const*> NameAndTypeResolver::resolveName(ASTString const& _name, Declaration const* _scope) const +{ + auto iterator = m_scopes.find(_scope); + if (iterator == end(m_scopes)) + return vector<Declaration const*>({}); + return iterator->second.resolveName(_name, false); +} + +vector<Declaration const*> NameAndTypeResolver::getNameFromCurrentScope(ASTString const& _name, bool _recursive) +{ + return m_currentScope->resolveName(_name, _recursive); +} + +vector<Declaration const*> NameAndTypeResolver::cleanedDeclarations( + Identifier const& _identifier, + vector<Declaration const*> const& _declarations +) +{ + solAssert(_declarations.size() > 1, ""); + vector<Declaration const*> uniqueFunctions; + + for (auto it = _declarations.begin(); it != _declarations.end(); ++it) + { + solAssert(*it, ""); + // the declaration is functionDefinition while declarations > 1 + FunctionDefinition const& functionDefinition = dynamic_cast<FunctionDefinition const&>(**it); + FunctionType functionType(functionDefinition); + for (auto parameter: functionType.getParameterTypes() + functionType.getReturnParameterTypes()) + if (!parameter) + BOOST_THROW_EXCEPTION( + DeclarationError() << + errinfo_sourceLocation(_identifier.getLocation()) << + errinfo_comment("Function type can not be used in this context") + ); + if (uniqueFunctions.end() == find_if( + uniqueFunctions.begin(), + uniqueFunctions.end(), + [&](Declaration const* d) + { + FunctionType newFunctionType(dynamic_cast<FunctionDefinition const&>(*d)); + return functionType.hasEqualArgumentTypes(newFunctionType); + } + )) + uniqueFunctions.push_back(*it); + } + return uniqueFunctions; +} + +void NameAndTypeResolver::importInheritedScope(ContractDefinition const& _base) +{ + auto iterator = m_scopes.find(&_base); + solAssert(iterator != end(m_scopes), ""); + for (auto const& nameAndDeclaration: iterator->second.getDeclarations()) + for (auto const& declaration: nameAndDeclaration.second) + // Import if it was declared in the base, is not the constructor and is visible in derived classes + if (declaration->getScope() == &_base && declaration->isVisibleInDerivedContracts()) + m_currentScope->registerDeclaration(*declaration); +} + +void NameAndTypeResolver::linearizeBaseContracts(ContractDefinition& _contract) const +{ + // order in the lists is from derived to base + // list of lists to linearize, the last element is the list of direct bases + list<list<ContractDefinition const*>> input(1, {}); + for (ASTPointer<InheritanceSpecifier> const& baseSpecifier: _contract.getBaseContracts()) + { + ASTPointer<Identifier> baseName = baseSpecifier->getName(); + auto base = dynamic_cast<ContractDefinition const*>(&baseName->getReferencedDeclaration()); + if (!base) + BOOST_THROW_EXCEPTION(baseName->createTypeError("Contract expected.")); + // "push_front" has the effect that bases mentioned later can overwrite members of bases + // mentioned earlier + input.back().push_front(base); + vector<ContractDefinition const*> const& basesBases = base->getLinearizedBaseContracts(); + if (basesBases.empty()) + BOOST_THROW_EXCEPTION(baseName->createTypeError("Definition of base has to precede definition of derived contract")); + input.push_front(list<ContractDefinition const*>(basesBases.begin(), basesBases.end())); + } + input.back().push_front(&_contract); + vector<ContractDefinition const*> result = cThreeMerge(input); + if (result.empty()) + BOOST_THROW_EXCEPTION(_contract.createTypeError("Linearization of inheritance graph impossible")); + _contract.setLinearizedBaseContracts(result); +} + +template <class _T> +vector<_T const*> NameAndTypeResolver::cThreeMerge(list<list<_T const*>>& _toMerge) +{ + // returns true iff _candidate appears only as last element of the lists + auto appearsOnlyAtHead = [&](_T const* _candidate) -> bool + { + for (list<_T const*> const& bases: _toMerge) + { + solAssert(!bases.empty(), ""); + if (find(++bases.begin(), bases.end(), _candidate) != bases.end()) + return false; + } + return true; + }; + // returns the next candidate to append to the linearized list or nullptr on failure + auto nextCandidate = [&]() -> _T const* + { + for (list<_T const*> const& bases: _toMerge) + { + solAssert(!bases.empty(), ""); + if (appearsOnlyAtHead(bases.front())) + return bases.front(); + } + return nullptr; + }; + // removes the given contract from all lists + auto removeCandidate = [&](_T const* _candidate) + { + for (auto it = _toMerge.begin(); it != _toMerge.end();) + { + it->remove(_candidate); + if (it->empty()) + it = _toMerge.erase(it); + else + ++it; + } + }; + + _toMerge.remove_if([](list<_T const*> const& _bases) { return _bases.empty(); }); + vector<_T const*> result; + while (!_toMerge.empty()) + { + _T const* candidate = nextCandidate(); + if (!candidate) + return vector<_T const*>(); + result.push_back(candidate); + removeCandidate(candidate); + } + return result; +} + +DeclarationRegistrationHelper::DeclarationRegistrationHelper(map<ASTNode const*, DeclarationContainer>& _scopes, + ASTNode& _astRoot): + m_scopes(_scopes), m_currentScope(nullptr) +{ + _astRoot.accept(*this); +} + +bool DeclarationRegistrationHelper::visit(ContractDefinition& _contract) +{ + registerDeclaration(_contract, true); + return true; +} + +void DeclarationRegistrationHelper::endVisit(ContractDefinition&) +{ + closeCurrentScope(); +} + +bool DeclarationRegistrationHelper::visit(StructDefinition& _struct) +{ + registerDeclaration(_struct, true); + return true; +} + +void DeclarationRegistrationHelper::endVisit(StructDefinition&) +{ + closeCurrentScope(); +} + +bool DeclarationRegistrationHelper::visit(EnumDefinition& _enum) +{ + registerDeclaration(_enum, true); + return true; +} + +void DeclarationRegistrationHelper::endVisit(EnumDefinition&) +{ + closeCurrentScope(); +} + +bool DeclarationRegistrationHelper::visit(EnumValue& _value) +{ + registerDeclaration(_value, false); + return true; +} + +bool DeclarationRegistrationHelper::visit(FunctionDefinition& _function) +{ + registerDeclaration(_function, true); + m_currentFunction = &_function; + return true; +} + +void DeclarationRegistrationHelper::endVisit(FunctionDefinition&) +{ + m_currentFunction = nullptr; + closeCurrentScope(); +} + +bool DeclarationRegistrationHelper::visit(ModifierDefinition& _modifier) +{ + registerDeclaration(_modifier, true); + m_currentFunction = &_modifier; + return true; +} + +void DeclarationRegistrationHelper::endVisit(ModifierDefinition&) +{ + m_currentFunction = nullptr; + closeCurrentScope(); +} + +void DeclarationRegistrationHelper::endVisit(VariableDeclarationStatement& _variableDeclarationStatement) +{ + // Register the local variables with the function + // This does not fit here perfectly, but it saves us another AST visit. + solAssert(m_currentFunction, "Variable declaration without function."); + m_currentFunction->addLocalVariable(_variableDeclarationStatement.getDeclaration()); +} + +bool DeclarationRegistrationHelper::visit(VariableDeclaration& _declaration) +{ + registerDeclaration(_declaration, false); + return true; +} + +bool DeclarationRegistrationHelper::visit(EventDefinition& _event) +{ + registerDeclaration(_event, true); + return true; +} + +void DeclarationRegistrationHelper::endVisit(EventDefinition&) +{ + closeCurrentScope(); +} + +void DeclarationRegistrationHelper::enterNewSubScope(Declaration const& _declaration) +{ + map<ASTNode const*, DeclarationContainer>::iterator iter; + bool newlyAdded; + tie(iter, newlyAdded) = m_scopes.emplace(&_declaration, DeclarationContainer(m_currentScope, &m_scopes[m_currentScope])); + solAssert(newlyAdded, "Unable to add new scope."); + m_currentScope = &_declaration; +} + +void DeclarationRegistrationHelper::closeCurrentScope() +{ + solAssert(m_currentScope, "Closed non-existing scope."); + m_currentScope = m_scopes[m_currentScope].getEnclosingDeclaration(); +} + +void DeclarationRegistrationHelper::registerDeclaration(Declaration& _declaration, bool _opensScope) +{ + if (!m_scopes[m_currentScope].registerDeclaration(_declaration, !_declaration.isVisibleInContract())) + { + SourceLocation firstDeclarationLocation; + SourceLocation secondDeclarationLocation; + Declaration const* conflictingDeclaration = m_scopes[m_currentScope].conflictingDeclaration(_declaration); + solAssert(conflictingDeclaration, ""); + + if (_declaration.getLocation().start < conflictingDeclaration->getLocation().start) + { + firstDeclarationLocation = _declaration.getLocation(); + secondDeclarationLocation = conflictingDeclaration->getLocation(); + } + else + { + firstDeclarationLocation = conflictingDeclaration->getLocation(); + secondDeclarationLocation = _declaration.getLocation(); + } + + BOOST_THROW_EXCEPTION( + DeclarationError() << + errinfo_sourceLocation(secondDeclarationLocation) << + errinfo_comment("Identifier already declared.") << + errinfo_secondarySourceLocation( + SecondarySourceLocation().append("The previous declaration is here:", firstDeclarationLocation) + ) + ); + } + + _declaration.setScope(m_currentScope); + if (_opensScope) + enterNewSubScope(_declaration); +} + +ReferencesResolver::ReferencesResolver( + ASTNode& _root, + NameAndTypeResolver& _resolver, + ContractDefinition const* _currentContract, + ParameterList const* _returnParameters, + bool _resolveInsideCode, + bool _allowLazyTypes +): + m_resolver(_resolver), + m_currentContract(_currentContract), + m_returnParameters(_returnParameters), + m_resolveInsideCode(_resolveInsideCode), + m_allowLazyTypes(_allowLazyTypes) +{ + _root.accept(*this); +} + +void ReferencesResolver::endVisit(VariableDeclaration& _variable) +{ + // endVisit because the internal type needs resolving if it is a user defined type + // or mapping + if (_variable.getTypeName()) + { + TypePointer type = _variable.getTypeName()->toType(); + using Location = VariableDeclaration::Location; + Location loc = _variable.referenceLocation(); + // References are forced to calldata for external function parameters (not return) + // and memory for parameters (also return) of publicly visible functions. + // They default to memory for function parameters and storage for local variables. + if (auto ref = dynamic_cast<ReferenceType const*>(type.get())) + { + if (_variable.isExternalCallableParameter()) + { + // force location of external function parameters (not return) to calldata + if (loc != Location::Default) + BOOST_THROW_EXCEPTION(_variable.createTypeError( + "Location has to be calldata for external functions " + "(remove the \"memory\" or \"storage\" keyword)." + )); + type = ref->copyForLocation(DataLocation::CallData, true); + } + else if (_variable.isCallableParameter() && _variable.getScope()->isPublic()) + { + // force locations of public or external function (return) parameters to memory + if (loc == VariableDeclaration::Location::Storage) + BOOST_THROW_EXCEPTION(_variable.createTypeError( + "Location has to be memory for publicly visible functions " + "(remove the \"storage\" keyword)." + )); + type = ref->copyForLocation(DataLocation::Memory, true); + } + else + { + if (loc == Location::Default) + loc = _variable.isCallableParameter() ? Location::Memory : Location::Storage; + bool isPointer = !_variable.isStateVariable(); + type = ref->copyForLocation( + loc == Location::Memory ? + DataLocation::Memory : + DataLocation::Storage, + isPointer + ); + } + } + else if (loc != Location::Default && !ref) + BOOST_THROW_EXCEPTION(_variable.createTypeError( + "Storage location can only be given for array or struct types." + )); + + _variable.setType(type); + + if (!_variable.getType()) + BOOST_THROW_EXCEPTION(_variable.getTypeName()->createTypeError("Invalid type name")); + } + else if (!m_allowLazyTypes) + BOOST_THROW_EXCEPTION(_variable.createTypeError("Explicit type needed.")); + // otherwise we have a "var"-declaration whose type is resolved by the first assignment +} + +bool ReferencesResolver::visit(Return& _return) +{ + _return.setFunctionReturnParameters(m_returnParameters); + return true; +} + +bool ReferencesResolver::visit(Mapping&) +{ + return true; +} + +bool ReferencesResolver::visit(UserDefinedTypeName& _typeName) +{ + auto declarations = m_resolver.getNameFromCurrentScope(_typeName.getName()); + if (declarations.empty()) + BOOST_THROW_EXCEPTION( + DeclarationError() << + errinfo_sourceLocation(_typeName.getLocation()) << + errinfo_comment("Undeclared identifier.") + ); + else if (declarations.size() > 1) + BOOST_THROW_EXCEPTION( + DeclarationError() << + errinfo_sourceLocation(_typeName.getLocation()) << + errinfo_comment("Duplicate identifier.") + ); + else + _typeName.setReferencedDeclaration(**declarations.begin()); + return false; +} + +bool ReferencesResolver::visit(Identifier& _identifier) +{ + auto declarations = m_resolver.getNameFromCurrentScope(_identifier.getName()); + if (declarations.empty()) + BOOST_THROW_EXCEPTION( + DeclarationError() << + errinfo_sourceLocation(_identifier.getLocation()) << + errinfo_comment("Undeclared identifier.") + ); + else if (declarations.size() == 1) + _identifier.setReferencedDeclaration(*declarations.front(), m_currentContract); + else + _identifier.setOverloadedDeclarations(m_resolver.cleanedDeclarations(_identifier, declarations)); + return false; +} + +} +} |