Split external type into ecoding and interface type.

7 files changed, 128 insertions, 55 deletions

diff --git a/libsolidity/Compiler.cpp b/libsolidity/Compiler.cpp
index 969c8f74..21eab230 100644
--- a/libsolidity/Compiler.cpp
+++ b/libsolidity/Compiler.cpp
@@ -280,15 +280,13 @@ void Compiler::appendCalldataUnpacker(TypePointers const& _typeParameters, bool
 
 	// Retain the offset pointer as base_offset, the point from which the data offsets are computed.
 	m_context << eth::Instruction::DUP1;
-	for (TypePointer const& type: _typeParameters)
+	for (TypePointer const& parameterType: _typeParameters)
 	{
 		// stack: v1 v2 ... v(k-1) base_offset current_offset
-		switch (type->category())
-		{
-		case Type::Category::Array:
+		TypePointer type = parameterType->encodingType();
+		if (type->category() == Type::Category::Array)
 		{
 			auto const& arrayType = dynamic_cast<ArrayType const&>(*type);
-			solAssert(arrayType.location() != DataLocation::Storage, "");
 			solAssert(!arrayType.baseType()->isDynamicallySized(), "Nested arrays not yet implemented.");
 			if (_fromMemory)
 			{
@@ -344,7 +342,8 @@ void Compiler::appendCalldataUnpacker(TypePointers const& _typeParameters, bool
 			}
 			break;
 		}
-		default:
+		else
+		{
 			solAssert(!type->isDynamicallySized(), "Unknown dynamically sized type: " + type->toString());
 			CompilerUtils(m_context).loadFromMemoryDynamic(*type, !_fromMemory, true);
 			CompilerUtils(m_context).moveToStackTop(1 + type->sizeOnStack());
diff --git a/libsolidity/CompilerUtils.cpp b/libsolidity/CompilerUtils.cpp
index d6624ca4..31000f0b 100644
--- a/libsolidity/CompilerUtils.cpp
+++ b/libsolidity/CompilerUtils.cpp
@@ -160,7 +160,7 @@ void CompilerUtils::encodeToMemory(
 	TypePointers targetTypes = _targetTypes.empty() ? _givenTypes : _targetTypes;
 	solAssert(targetTypes.size() == _givenTypes.size(), "");
 	for (TypePointer& t: targetTypes)
-		t = t->mobileType()->externalType();
+		t = t->mobileType()->encodingType();
 
 	// Stack during operation:
 	// <v1> <v2> ... <vn> <mem_start> <dyn_head_1> ... <dyn_head_r> <end_of_mem>
diff --git a/libsolidity/InterfaceHandler.cpp b/libsolidity/InterfaceHandler.cpp
index 50006caf..4837fcfe 100644
--- a/libsolidity/InterfaceHandler.cpp
+++ b/libsolidity/InterfaceHandler.cpp
@@ -57,7 +57,7 @@ string InterfaceHandler::abiInterface(ContractDefinition const& _contractDef)
 
 	for (auto it: _contractDef.interfaceFunctions())
 	{
-		auto externalFunctionType = it.second->externalFunctionType();
+		auto externalFunctionType = it.second->interfaceFunctionType();
 		Json::Value method;
 		method["type"] = "function";
 		method["name"] = it.second->declaration().name();
@@ -76,7 +76,7 @@ string InterfaceHandler::abiInterface(ContractDefinition const& _contractDef)
 	{
 		Json::Value method;
 		method["type"] = "constructor";
-		auto externalFunction = FunctionType(*_contractDef.constructor()).externalFunctionType();
+		auto externalFunction = FunctionType(*_contractDef.constructor()).interfaceFunctionType();
 		solAssert(!!externalFunction, "");
 		method["inputs"] = populateParameters(
 			externalFunction->parameterNames(),
@@ -120,7 +120,7 @@ string InterfaceHandler::ABISolidityInterface(ContractDefinition const& _contrac
 	};
 	if (_contractDef.constructor())
 	{
-		auto externalFunction = FunctionType(*_contractDef.constructor()).externalFunctionType();
+		auto externalFunction = FunctionType(*_contractDef.constructor()).interfaceFunctionType();
 		solAssert(!!externalFunction, "");
 		ret +=
 			"function " +
diff --git a/libsolidity/ReferencesResolver.cpp b/libsolidity/ReferencesResolver.cpp
index 623ac8f7..cb34c47e 100644
--- a/libsolidity/ReferencesResolver.cpp
+++ b/libsolidity/ReferencesResolver.cpp
@@ -106,27 +106,45 @@ void ReferencesResolver::endVisit(VariableDeclaration const& _variable)
 		// 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.
+		// As an exception, "storage" is allowed for library functions.
 		if (auto ref = dynamic_cast<ReferenceType const*>(type.get()))
 		{
-			if (_variable.isExternalCallableParameter())
+			if (_variable.isCallableParameter())
 			{
-				// 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.scope()->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);
+				auto const& contract = dynamic_cast<ContractDefinition const&>(*_variable.scope()->scope());
+				if (_variable.isExternalCallableParameter())
+				{
+					if (contract.isLibrary())
+					{
+						if (loc == Location::Memory)
+							BOOST_THROW_EXCEPTION(_variable.createTypeError(
+								"Location has to be calldata or storage for external "
+								"library functions (remove the \"memory\" keyword)."
+							));
+					}
+					else
+					{
+						// 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)."
+							));
+					}
+					if (loc == Location::Default)
+						type = ref->copyForLocation(DataLocation::CallData, true);
+				}
+				else if (_variable.isCallableParameter() && _variable.scope()->isPublic())
+				{
+					// force locations of public or external function (return) parameters to memory
+					if (loc == Location::Storage && !contract.isLibrary())
+						BOOST_THROW_EXCEPTION(_variable.createTypeError(
+							"Location has to be memory for publicly visible functions "
+							"(remove the \"storage\" keyword)."
+						));
+					if (loc == Location::Default)
+						type = ref->copyForLocation(DataLocation::Memory, true);
+				}
 			}
 			else
 			{
diff --git a/libsolidity/TypeChecker.cpp b/libsolidity/TypeChecker.cpp
index 48a8a536..74347e1f 100644
--- a/libsolidity/TypeChecker.cpp
+++ b/libsolidity/TypeChecker.cpp
@@ -397,11 +397,12 @@ bool TypeChecker::visit(StructDefinition const& _struct)
 
 bool TypeChecker::visit(FunctionDefinition const& _function)
 {
+	bool isLibraryFunction = dynamic_cast<ContractDefinition const&>(*_function.scope()).isLibrary();
 	for (ASTPointer<VariableDeclaration> const& var: _function.parameters() + _function.returnParameters())
 	{
 		if (!type(*var)->canLiveOutsideStorage())
 			typeError(*var, "Type is required to live outside storage.");
-		if (_function.visibility() >= FunctionDefinition::Visibility::Public && !(type(*var)->externalType()))
+		if (_function.visibility() >= FunctionDefinition::Visibility::Public && !(type(*var)->interfaceType(isLibraryFunction)))
 			typeError(*var, "Internal type is not allowed for public and external functions.");
 	}
 	for (ASTPointer<ModifierInvocation> const& modifier: _function.modifiers())
@@ -490,7 +491,7 @@ bool TypeChecker::visit(VariableDeclaration const& _variable)
 	}
 	else if (
 		_variable.visibility() >= VariableDeclaration::Visibility::Public &&
-		!FunctionType(_variable).externalType()
+		!FunctionType(_variable).interfaceFunctionType()
 	)
 		typeError(_variable, "Internal type is not allowed for public state variables.");
 	return false;
@@ -557,7 +558,7 @@ bool TypeChecker::visit(EventDefinition const& _eventDef)
 			typeError(_eventDef, "More than 3 indexed arguments for event.");
 		if (!type(*var)->canLiveOutsideStorage())
 			typeError(*var, "Type is required to live outside storage.");
-		if (!type(*var)->externalType())
+		if (!type(*var)->interfaceType(false))
 			typeError(*var, "Internal type is not allowed as event parameter type.");
 	}
 	return false;
diff --git a/libsolidity/Types.cpp b/libsolidity/Types.cpp
index 435385e6..f7e67696 100644
--- a/libsolidity/Types.cpp
+++ b/libsolidity/Types.cpp
@@ -839,11 +839,22 @@ string ArrayType::toString(bool _short) const
 	return ret;
 }
 
-TypePointer ArrayType::externalType() const
+TypePointer ArrayType::encodingType() const
 {
+	if (location() == DataLocation::Storage)
+		return make_shared<IntegerType>(256);
+	else
+		return this->copyForLocation(DataLocation::Memory, true);
+}
+
+TypePointer ArrayType::interfaceType(bool _inLibrary) const
+{
+	if (_inLibrary && location() == DataLocation::Storage)
+		return shared_from_this();
+
 	if (m_arrayKind != ArrayKind::Ordinary)
 		return this->copyForLocation(DataLocation::Memory, true);
-	TypePointer baseExt = m_baseType->externalType();
+	TypePointer baseExt = m_baseType->interfaceType(_inLibrary);
 	if (!baseExt)
 		return TypePointer();
 	if (m_baseType->category() == Category::Array && m_baseType->isDynamicallySized())
@@ -1059,6 +1070,14 @@ MemberList const& StructType::members() const
 	return *m_members;
 }
 
+TypePointer StructType::interfaceType(bool _inLibrary) const
+{
+	if (_inLibrary && location() == DataLocation::Storage)
+		return shared_from_this();
+	else
+		return TypePointer();
+}
+
 TypePointer StructType::copyForLocation(DataLocation _location, bool _isPointer) const
 {
 	auto copy = make_shared<StructType>(m_struct, _location);
@@ -1330,21 +1349,25 @@ unsigned FunctionType::sizeOnStack() const
 	return size;
 }
 
-FunctionTypePointer FunctionType::externalFunctionType() const
+FunctionTypePointer FunctionType::interfaceFunctionType() const
 {
+	// Note that m_declaration might also be a state variable!
+	solAssert(m_declaration, "Declaration needed to determine interface function type.");
+	bool isLibraryFunction = dynamic_cast<ContractDefinition const&>(*m_declaration->scope()).isLibrary();
+
 	TypePointers paramTypes;
 	TypePointers retParamTypes;
 
 	for (auto type: m_parameterTypes)
 	{
-		if (auto ext = type->externalType())
+		if (auto ext = type->interfaceType(isLibraryFunction))
 			paramTypes.push_back(ext);
 		else
 			return FunctionTypePointer();
 	}
 	for (auto type: m_returnParameterTypes)
 	{
-		if (auto ext = type->externalType())
+		if (auto ext = type->interfaceType(isLibraryFunction))
 			retParamTypes.push_back(ext);
 		else
 			return FunctionTypePointer();
@@ -1462,7 +1485,7 @@ string FunctionType::externalSignature(std::string const& _name) const
 	}
 	string ret = funcName + "(";
 
-	FunctionTypePointer external = externalFunctionType();
+	FunctionTypePointer external = interfaceFunctionType();
 	solAssert(!!external, "External function type requested.");
 	TypePointers externalParameterTypes = external->parameterTypes();
 	for (auto it = externalParameterTypes.cbegin(); it != externalParameterTypes.cend(); ++it)
diff --git a/libsolidity/Types.h b/libsolidity/Types.h
index 73111e48..972876e9 100644
--- a/libsolidity/Types.h
+++ b/libsolidity/Types.h
@@ -226,9 +226,16 @@ public:
 		);
 	}
 
-	/// @returns a type suitable for outside of Solidity, i.e. for contract types it returns address.
+	/// @returns a (simpler) type that is encoded in the same way for external function calls.
+	/// This for example returns address for contract types.
 	/// If there is no such type, returns an empty shared pointer.
-	virtual TypePointer externalType() const { return TypePointer(); }
+	virtual TypePointer encodingType() const { return TypePointer(); }
+	/// @returns a type that will be used outside of Solidity for e.g. function signatures.
+	/// This for example returns address for contract types.
+	/// If there is no such type, returns an empty shared pointer.
+	/// @param _inLibrary if set, returns types as used in a library, e.g. struct and contract types
+	/// are returned without modification.
+	virtual TypePointer interfaceType(bool /*_inLibrary*/) const { return TypePointer(); }
 
 protected:
 	/// Convenience object used when returning an empty member list.
@@ -264,7 +271,8 @@ public:
 
 	virtual std::string toString(bool _short) const override;
 
-	virtual TypePointer externalType() const override { return shared_from_this(); }
+	virtual TypePointer encodingType() const override { return shared_from_this(); }
+	virtual TypePointer interfaceType(bool) const override { return shared_from_this(); }
 
 	int numBits() const { return m_bits; }
 	bool isAddress() const { return m_modifier == Modifier::Address; }
@@ -369,7 +377,8 @@ public:
 	virtual bool isValueType() const override { return true; }
 
 	virtual std::string toString(bool) const override { return "bytes" + dev::toString(m_bytes); }
-	virtual TypePointer externalType() const override { return shared_from_this(); }
+	virtual TypePointer encodingType() const override { return shared_from_this(); }
+	virtual TypePointer interfaceType(bool) const override { return shared_from_this(); }
 
 	int numBytes() const { return m_bytes; }
 
@@ -395,7 +404,8 @@ public:
 
 	virtual std::string toString(bool) const override { return "bool"; }
 	virtual u256 literalValue(Literal const* _literal) const override;
-	virtual TypePointer externalType() const override { return shared_from_this(); }
+	virtual TypePointer encodingType() const override { return shared_from_this(); }
+	virtual TypePointer interfaceType(bool) const override { return shared_from_this(); }
 };
 
 /**
@@ -493,7 +503,8 @@ public:
 	{
 		return isString() ? EmptyMemberList : s_arrayTypeMemberList;
 	}
-	virtual TypePointer externalType() const override;
+	virtual TypePointer encodingType() const override;
+	virtual TypePointer interfaceType(bool _inLibrary) const override;
 
 	/// @returns true if this is a byte array or a string
 	bool isByteArray() const { return m_arrayKind != ArrayKind::Ordinary; }
@@ -534,7 +545,7 @@ public:
 	virtual bool operator==(Type const& _other) const override;
 	virtual unsigned calldataEncodedSize(bool _padded ) const override
 	{
-		return externalType()->calldataEncodedSize(_padded);
+		return encodingType()->calldataEncodedSize(_padded);
 	}
 	virtual unsigned storageBytes() const override { return 20; }
 	virtual bool canLiveOutsideStorage() const override { return true; }
@@ -542,10 +553,14 @@ public:
 	virtual std::string toString(bool _short) const override;
 
 	virtual MemberList const& members() const override;
-	virtual TypePointer externalType() const override
+	virtual TypePointer encodingType() const override
 	{
 		return std::make_shared<IntegerType>(160, IntegerType::Modifier::Address);
 	}
+	virtual TypePointer interfaceType(bool _inLibrary) const override
+	{
+		return _inLibrary ? shared_from_this() : encodingType();
+	}
 
 	bool isSuper() const { return m_super; }
 	ContractDefinition const& contractDefinition() const { return m_contract; }
@@ -566,7 +581,7 @@ private:
 	ContractDefinition const& m_contract;
 	/// If true, it is the "super" type of the current contract, i.e. it contains only inherited
 	/// members.
-	bool m_super;
+	bool m_super = false;
 	/// Type of the constructor, @see constructorType. Lazily initialized.
 	mutable FunctionTypePointer m_constructorType;
 	/// List of member types, will be lazy-initialized because of recursive references.
@@ -591,6 +606,11 @@ public:
 	virtual std::string toString(bool _short) const override;
 
 	virtual MemberList const& members() const override;
+	virtual TypePointer encodingType() const override
+	{
+		return location() == DataLocation::Storage ? std::make_shared<IntegerType>(256) : TypePointer();
+	}
+	virtual TypePointer interfaceType(bool _inLibrary) const override;
 
 	TypePointer copyForLocation(DataLocation _location, bool _isPointer) const override;
 
@@ -624,7 +644,7 @@ public:
 	virtual bool operator==(Type const& _other) const override;
 	virtual unsigned calldataEncodedSize(bool _padded) const override
 	{
-		return externalType()->calldataEncodedSize(_padded);
+		return encodingType()->calldataEncodedSize(_padded);
 	}
 	virtual unsigned storageBytes() const override;
 	virtual bool canLiveOutsideStorage() const override { return true; }
@@ -632,10 +652,14 @@ public:
 	virtual bool isValueType() const override { return true; }
 
 	virtual bool isExplicitlyConvertibleTo(Type const& _convertTo) const override;
-	virtual TypePointer externalType() const override
+	virtual TypePointer encodingType() const override
 	{
 		return std::make_shared<IntegerType>(8 * int(storageBytes()));
 	}
+	virtual TypePointer interfaceType(bool _inLibrary) const override
+	{
+		return _inLibrary ? shared_from_this() : encodingType();
+	}
 
 	EnumDefinition const& enumDefinition() const { return m_enum; }
 	/// @returns the value that the string has in the Enum
@@ -684,13 +708,6 @@ public:
 
 	virtual Category category() const override { return Category::Function; }
 
-	/// @returns TypePointer of a new FunctionType object. All input/return parameters are an
-	/// appropriate external types of input/return parameters of current function.
-	/// Returns an empty shared pointer if one of the input/return parameters does not have an
-	/// external type.
-	FunctionTypePointer externalFunctionType() const;
-	virtual TypePointer externalType() const override { return externalFunctionType(); }
-
 	/// Creates the type of a function.
 	explicit FunctionType(FunctionDefinition const& _function, bool _isInternal = true);
 	/// Creates the accessor function type of a state variable.
@@ -749,6 +766,13 @@ public:
 	virtual unsigned sizeOnStack() const override;
 	virtual MemberList const& members() const override;
 
+	/// @returns TypePointer of a new FunctionType object. All input/return parameters are an
+	/// appropriate external types (i.e. the interfaceType()s) of input/return parameters of
+	/// current function.
+	/// Returns an empty shared pointer if one of the input/return parameters does not have an
+	/// external type.
+	FunctionTypePointer interfaceFunctionType() const;
+
 	/// @returns true if this function can take the given argument types (possibly
 	/// after implicit conversion).
 	bool canTakeArguments(TypePointers const& _arguments) const;
@@ -823,6 +847,14 @@ public:
 	virtual bool operator==(Type const& _other) const override;
 	virtual std::string toString(bool _short) const override;
 	virtual bool canLiveOutsideStorage() const override { return false; }
+	virtual TypePointer encodingType() const override
+	{
+		return std::make_shared<IntegerType>(256);
+	}
+	virtual TypePointer interfaceType(bool _inLibrary) const override
+	{
+		return _inLibrary ? shared_from_this() : TypePointer();
+	}
 
 	TypePointer const& keyType() const { return m_keyType; }
 	TypePointer const& valueType() const { return m_valueType; }