solidity/libsolidity/analysis/StaticAnalyzer.cpp
2017-05-03 11:26:21 +02:00

131 lines
3.6 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 Federico Bond <federicobond@gmail.com>
* @date 2016
* Static analyzer and checker.
*/
#include <libsolidity/analysis/StaticAnalyzer.h>
#include <memory>
#include <libsolidity/ast/AST.h>
using namespace std;
using namespace dev;
using namespace dev::solidity;
bool StaticAnalyzer::analyze(SourceUnit const& _sourceUnit)
{
_sourceUnit.accept(*this);
return Error::containsOnlyWarnings(m_errors);
}
bool StaticAnalyzer::visit(ContractDefinition const& _contract)
{
m_library = _contract.isLibrary();
return true;
}
void StaticAnalyzer::endVisit(ContractDefinition const&)
{
m_library = false;
}
bool StaticAnalyzer::visit(FunctionDefinition const& _function)
{
if (_function.isImplemented())
m_currentFunction = &_function;
else
solAssert(!m_currentFunction, "");
solAssert(m_localVarUseCount.empty(), "");
m_nonPayablePublic = _function.isPublic() && !_function.isPayable();
return true;
}
void StaticAnalyzer::endVisit(FunctionDefinition const&)
{
m_currentFunction = nullptr;
m_nonPayablePublic = false;
for (auto const& var: m_localVarUseCount)
if (var.second == 0)
warning(var.first->location(), "Unused local variable");
m_localVarUseCount.clear();
}
bool StaticAnalyzer::visit(Identifier const& _identifier)
{
if (m_currentFunction)
if (auto var = dynamic_cast<VariableDeclaration const*>(_identifier.annotation().referencedDeclaration))
{
solAssert(!var->name().empty(), "");
if (var->isLocalVariable())
m_localVarUseCount[var] += 1;
}
return true;
}
bool StaticAnalyzer::visit(VariableDeclaration const& _variable)
{
if (m_currentFunction)
{
solAssert(_variable.isLocalVariable(), "");
if (_variable.name() != "")
// This is not a no-op, the entry might pre-exist.
m_localVarUseCount[&_variable] += 0;
}
return true;
}
bool StaticAnalyzer::visit(Return const& _return)
{
// If the return has an expression, it counts as
// a "use" of the return parameters.
if (m_currentFunction && _return.expression())
for (auto const& var: m_currentFunction->returnParameters())
if (!var->name().empty())
m_localVarUseCount[var.get()] += 1;
return true;
}
bool StaticAnalyzer::visit(ExpressionStatement const& _statement)
{
if (_statement.expression().annotation().isPure)
warning(_statement.location(), "Statement has no effect.");
return true;
}
bool StaticAnalyzer::visit(MemberAccess const& _memberAccess)
{
if (m_nonPayablePublic && !m_library)
if (MagicType const* type = dynamic_cast<MagicType const*>(_memberAccess.expression().annotation().type.get()))
if (type->kind() == MagicType::Kind::Message && _memberAccess.memberName() == "value")
warning(_memberAccess.location(), "\"msg.value\" used in non-payable function. Do you want to add the \"payable\" modifier to this function?");
return true;
}
void StaticAnalyzer::warning(SourceLocation const& _location, string const& _description)
{
auto err = make_shared<Error>(Error::Type::Warning);
*err <<
errinfo_sourceLocation(_location) <<
errinfo_comment(_description);
m_errors.push_back(err);
}