solidity/libsolidity/analysis/ReferencesResolver.cpp

477 lines
15 KiB
C++

/*
This file is part of solidity.
solidity 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.
solidity 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 solidity. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @author Christian <c@ethdev.com>
* @date 2015
* Component that resolves type names to types and annotates the AST accordingly.
*/
#include <libsolidity/analysis/ReferencesResolver.h>
#include <libsolidity/analysis/NameAndTypeResolver.h>
#include <libsolidity/analysis/ConstantEvaluator.h>
#include <libsolidity/ast/AST.h>
#include <libsolidity/ast/TypeProvider.h>
#include <libyul/AsmAnalysis.h>
#include <libyul/AsmAnalysisInfo.h>
#include <libyul/AsmData.h>
#include <libyul/backends/evm/EVMDialect.h>
#include <liblangutil/ErrorReporter.h>
#include <liblangutil/Exceptions.h>
#include <libdevcore/StringUtils.h>
#include <boost/algorithm/string.hpp>
#include <boost/range/adaptor/transformed.hpp>
using namespace std;
using namespace langutil;
namespace dev
{
namespace solidity
{
bool ReferencesResolver::resolve(ASTNode const& _root)
{
_root.accept(*this);
return !m_errorOccurred;
}
bool ReferencesResolver::visit(Block const& _block)
{
if (!m_resolveInsideCode)
return false;
m_resolver.setScope(&_block);
return true;
}
void ReferencesResolver::endVisit(Block const& _block)
{
if (!m_resolveInsideCode)
return;
m_resolver.setScope(_block.scope());
}
bool ReferencesResolver::visit(ForStatement const& _for)
{
if (!m_resolveInsideCode)
return false;
m_resolver.setScope(&_for);
return true;
}
void ReferencesResolver::endVisit(ForStatement const& _for)
{
if (!m_resolveInsideCode)
return;
m_resolver.setScope(_for.scope());
}
void ReferencesResolver::endVisit(VariableDeclarationStatement const& _varDeclStatement)
{
if (!m_resolveInsideCode)
return;
for (auto const& var: _varDeclStatement.declarations())
if (var)
m_resolver.activateVariable(var->name());
}
bool ReferencesResolver::visit(Identifier const& _identifier)
{
auto declarations = m_resolver.nameFromCurrentScope(_identifier.name());
if (declarations.empty())
{
string suggestions = m_resolver.similarNameSuggestions(_identifier.name());
string errorMessage = "Undeclared identifier.";
if (!suggestions.empty())
{
if ("\"" + _identifier.name() + "\"" == suggestions)
errorMessage += " " + std::move(suggestions) + " is not (or not yet) visible at this point.";
else
errorMessage += " Did you mean " + std::move(suggestions) + "?";
}
declarationError(_identifier.location(), errorMessage);
}
else if (declarations.size() == 1)
_identifier.annotation().referencedDeclaration = declarations.front();
else
_identifier.annotation().overloadedDeclarations =
m_resolver.cleanedDeclarations(_identifier, declarations);
return false;
}
bool ReferencesResolver::visit(ElementaryTypeName const& _typeName)
{
if (!_typeName.annotation().type)
{
_typeName.annotation().type = TypeProvider::fromElementaryTypeName(_typeName.typeName());
if (_typeName.stateMutability().is_initialized())
{
// for non-address types this was already caught by the parser
solAssert(_typeName.annotation().type->category() == Type::Category::Address, "");
switch(*_typeName.stateMutability())
{
case StateMutability::Payable:
_typeName.annotation().type = TypeProvider::payableAddress();
break;
case StateMutability::NonPayable:
_typeName.annotation().type = TypeProvider::address();
break;
default:
m_errorReporter.typeError(
_typeName.location(),
"Address types can only be payable or non-payable."
);
break;
}
}
}
return true;
}
bool ReferencesResolver::visit(FunctionDefinition const& _functionDefinition)
{
m_returnParameters.push_back(_functionDefinition.returnParameterList().get());
return true;
}
void ReferencesResolver::endVisit(FunctionDefinition const&)
{
solAssert(!m_returnParameters.empty(), "");
m_returnParameters.pop_back();
}
bool ReferencesResolver::visit(ModifierDefinition const&)
{
m_returnParameters.push_back(nullptr);
return true;
}
void ReferencesResolver::endVisit(ModifierDefinition const&)
{
solAssert(!m_returnParameters.empty(), "");
m_returnParameters.pop_back();
}
void ReferencesResolver::endVisit(UserDefinedTypeName const& _typeName)
{
Declaration const* declaration = m_resolver.pathFromCurrentScope(_typeName.namePath());
if (!declaration)
{
fatalDeclarationError(_typeName.location(), "Identifier not found or not unique.");
return;
}
_typeName.annotation().referencedDeclaration = declaration;
if (StructDefinition const* structDef = dynamic_cast<StructDefinition const*>(declaration))
_typeName.annotation().type = TypeProvider::structType(*structDef, DataLocation::Storage);
else if (EnumDefinition const* enumDef = dynamic_cast<EnumDefinition const*>(declaration))
_typeName.annotation().type = TypeProvider::enumType(*enumDef);
else if (ContractDefinition const* contract = dynamic_cast<ContractDefinition const*>(declaration))
_typeName.annotation().type = TypeProvider::contract(*contract);
else
{
_typeName.annotation().type = TypeProvider::emptyTuple();
typeError(_typeName.location(), "Name has to refer to a struct, enum or contract.");
}
}
void ReferencesResolver::endVisit(FunctionTypeName const& _typeName)
{
switch (_typeName.visibility())
{
case VariableDeclaration::Visibility::Internal:
case VariableDeclaration::Visibility::External:
break;
default:
fatalTypeError(_typeName.location(), "Invalid visibility, can only be \"external\" or \"internal\".");
return;
}
if (_typeName.isPayable() && _typeName.visibility() != VariableDeclaration::Visibility::External)
{
fatalTypeError(_typeName.location(), "Only external function types can be payable.");
return;
}
if (_typeName.visibility() == VariableDeclaration::Visibility::External)
for (auto const& t: _typeName.parameterTypes() + _typeName.returnParameterTypes())
{
solAssert(t->annotation().type, "Type not set for parameter.");
if (!t->annotation().type->interfaceType(false).get())
{
fatalTypeError(t->location(), "Internal type cannot be used for external function type.");
return;
}
}
_typeName.annotation().type = TypeProvider::function(_typeName);
}
void ReferencesResolver::endVisit(Mapping const& _typeName)
{
TypePointer keyType = _typeName.keyType().annotation().type;
TypePointer valueType = _typeName.valueType().annotation().type;
// Convert key type to memory.
keyType = TypeProvider::withLocationIfReference(DataLocation::Memory, keyType);
// Convert value type to storage reference.
valueType = TypeProvider::withLocationIfReference(DataLocation::Storage, valueType);
_typeName.annotation().type = TypeProvider::mapping(keyType, valueType);
}
void ReferencesResolver::endVisit(ArrayTypeName const& _typeName)
{
TypePointer baseType = _typeName.baseType().annotation().type;
if (!baseType)
{
solAssert(!m_errorReporter.errors().empty(), "");
return;
}
if (baseType->storageBytes() == 0)
fatalTypeError(_typeName.baseType().location(), "Illegal base type of storage size zero for array.");
if (Expression const* length = _typeName.length())
{
TypePointer& lengthTypeGeneric = length->annotation().type;
if (!lengthTypeGeneric)
lengthTypeGeneric = ConstantEvaluator(m_errorReporter).evaluate(*length);
RationalNumberType const* lengthType = dynamic_cast<RationalNumberType const*>(lengthTypeGeneric);
if (!lengthType || !lengthType->mobileType())
fatalTypeError(length->location(), "Invalid array length, expected integer literal or constant expression.");
else if (lengthType->isZero())
fatalTypeError(length->location(), "Array with zero length specified.");
else if (lengthType->isFractional())
fatalTypeError(length->location(), "Array with fractional length specified.");
else if (lengthType->isNegative())
fatalTypeError(length->location(), "Array with negative length specified.");
else
_typeName.annotation().type = TypeProvider::array(DataLocation::Storage, baseType, lengthType->literalValue(nullptr));
}
else
_typeName.annotation().type = TypeProvider::array(DataLocation::Storage, baseType);
}
bool ReferencesResolver::visit(InlineAssembly const& _inlineAssembly)
{
m_resolver.warnVariablesNamedLikeInstructions();
// Errors created in this stage are completely ignored because we do not yet know
// the type and size of external identifiers, which would result in false errors.
// The only purpose of this step is to fill the inline assembly annotation with
// external references.
ErrorList errors;
ErrorReporter errorsIgnored(errors);
yul::ExternalIdentifierAccess::Resolver resolver =
[&](yul::Identifier const& _identifier, yul::IdentifierContext, bool _crossesFunctionBoundary) {
auto declarations = m_resolver.nameFromCurrentScope(_identifier.name.str());
bool isSlot = boost::algorithm::ends_with(_identifier.name.str(), "_slot");
bool isOffset = boost::algorithm::ends_with(_identifier.name.str(), "_offset");
if (isSlot || isOffset)
{
// special mode to access storage variables
if (!declarations.empty())
// the special identifier exists itself, we should not allow that.
return size_t(-1);
string realName = _identifier.name.str().substr(0, _identifier.name.str().size() - (
isSlot ?
string("_slot").size() :
string("_offset").size()
));
if (realName.empty())
{
declarationError(_identifier.location, "In variable names _slot and _offset can only be used as a suffix.");
return size_t(-1);
}
declarations = m_resolver.nameFromCurrentScope(realName);
}
if (declarations.size() > 1)
{
declarationError(_identifier.location, "Multiple matching identifiers. Resolving overloaded identifiers is not supported.");
return size_t(-1);
}
else if (declarations.size() == 0)
return size_t(-1);
if (auto var = dynamic_cast<VariableDeclaration const*>(declarations.front()))
if (var->isLocalVariable() && _crossesFunctionBoundary)
{
declarationError(_identifier.location, "Cannot access local Solidity variables from inside an inline assembly function.");
return size_t(-1);
}
_inlineAssembly.annotation().externalReferences[&_identifier].isSlot = isSlot;
_inlineAssembly.annotation().externalReferences[&_identifier].isOffset = isOffset;
_inlineAssembly.annotation().externalReferences[&_identifier].declaration = declarations.front();
return size_t(1);
};
// Will be re-generated later with correct information
// We use the latest EVM version because we will re-run it anyway.
yul::AsmAnalysisInfo analysisInfo;
boost::optional<Error::Type> errorTypeForLoose = Error::Type::SyntaxError;
yul::AsmAnalyzer(
analysisInfo,
errorsIgnored,
errorTypeForLoose,
yul::EVMDialect::looseAssemblyForEVM(EVMVersion{}),
resolver
).analyze(_inlineAssembly.operations());
return false;
}
bool ReferencesResolver::visit(Return const& _return)
{
solAssert(!m_returnParameters.empty(), "");
_return.annotation().functionReturnParameters = m_returnParameters.back();
return true;
}
void ReferencesResolver::endVisit(VariableDeclaration const& _variable)
{
if (_variable.annotation().type)
return;
if (_variable.isConstant() && !_variable.isStateVariable())
m_errorReporter.declarationError(_variable.location(), "The \"constant\" keyword can only be used for state variables.");
if (!_variable.typeName())
{
// This can still happen in very unusual cases where a developer uses constructs, such as
// `var a;`, however, such code will have generated errors already.
// However, we cannot blindingly solAssert() for that here, as the TypeChecker (which is
// invoking ReferencesResolver) is generating it, so the error is most likely(!) generated
// after this step.
return;
}
using Location = VariableDeclaration::Location;
Location varLoc = _variable.referenceLocation();
DataLocation typeLoc = DataLocation::Memory;
set<Location> allowedDataLocations = _variable.allowedDataLocations();
if (!allowedDataLocations.count(varLoc))
{
auto locationToString = [](VariableDeclaration::Location _location) -> string
{
switch (_location)
{
case Location::Memory: return "\"memory\"";
case Location::Storage: return "\"storage\"";
case Location::CallData: return "\"calldata\"";
case Location::Unspecified: return "none";
}
return {};
};
string errorString;
if (!_variable.hasReferenceOrMappingType())
errorString = "Data location can only be specified for array, struct or mapping types";
else
{
errorString = "Data location must be " +
joinHumanReadable(
allowedDataLocations | boost::adaptors::transformed(locationToString),
", ",
" or "
);
if (_variable.isCallableParameter())
errorString +=
" for " +
string(_variable.isReturnParameter() ? "return " : "") +
"parameter in" +
string(_variable.isExternalCallableParameter() ? " external" : "") +
" function";
else
errorString += " for variable";
}
errorString += ", but " + locationToString(varLoc) + " was given.";
typeError(_variable.location(), errorString);
solAssert(!allowedDataLocations.empty(), "");
varLoc = *allowedDataLocations.begin();
}
// Find correct data location.
if (_variable.isEventParameter())
{
solAssert(varLoc == Location::Unspecified, "");
typeLoc = DataLocation::Memory;
}
else if (_variable.isStateVariable())
{
solAssert(varLoc == Location::Unspecified, "");
typeLoc = _variable.isConstant() ? DataLocation::Memory : DataLocation::Storage;
}
else if (
dynamic_cast<StructDefinition const*>(_variable.scope()) ||
dynamic_cast<EnumDefinition const*>(_variable.scope())
)
// The actual location will later be changed depending on how the type is used.
typeLoc = DataLocation::Storage;
else
switch (varLoc)
{
case Location::Memory:
typeLoc = DataLocation::Memory;
break;
case Location::Storage:
typeLoc = DataLocation::Storage;
break;
case Location::CallData:
typeLoc = DataLocation::CallData;
break;
case Location::Unspecified:
solAssert(!_variable.hasReferenceOrMappingType(), "Data location not properly set.");
}
TypePointer type = _variable.typeName()->annotation().type;
if (auto ref = dynamic_cast<ReferenceType const*>(type))
{
bool isPointer = !_variable.isStateVariable();
type = TypeProvider::withLocation(ref, typeLoc, isPointer);
}
_variable.annotation().type = type;
}
void ReferencesResolver::typeError(SourceLocation const& _location, string const& _description)
{
m_errorOccurred = true;
m_errorReporter.typeError(_location, _description);
}
void ReferencesResolver::fatalTypeError(SourceLocation const& _location, string const& _description)
{
m_errorOccurred = true;
m_errorReporter.fatalTypeError(_location, _description);
}
void ReferencesResolver::declarationError(SourceLocation const& _location, string const& _description)
{
m_errorOccurred = true;
m_errorReporter.declarationError(_location, _description);
}
void ReferencesResolver::fatalDeclarationError(SourceLocation const& _location, string const& _description)
{
m_errorOccurred = true;
m_errorReporter.fatalDeclarationError(_location, _description);
}
}
}