solidity/Types.h
2015-02-23 18:25:49 +01:00

649 lines
26 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 data types
*/
#pragma once
#include <memory>
#include <string>
#include <map>
#include <boost/noncopyable.hpp>
#include <libdevcore/Common.h>
#include <libsolidity/Exceptions.h>
#include <libsolidity/ASTForward.h>
#include <libsolidity/Token.h>
namespace dev
{
namespace solidity
{
class Type; // forward
class FunctionType; // forward
using TypePointer = std::shared_ptr<Type const>;
using FunctionTypePointer = std::shared_ptr<FunctionType const>;
using TypePointers = std::vector<TypePointer>;
/**
* List of members of a type.
*/
class MemberList
{
public:
using MemberMap = std::vector<std::pair<std::string, TypePointer>>;
MemberList() {}
explicit MemberList(MemberMap const& _members): m_memberTypes(_members) {}
TypePointer getMemberType(std::string const& _name) const
{
for (auto const& it: m_memberTypes)
if (it.first == _name)
return it.second;
return TypePointer();
}
MemberMap::const_iterator begin() const { return m_memberTypes.begin(); }
MemberMap::const_iterator end() const { return m_memberTypes.end(); }
private:
MemberMap m_memberTypes;
};
/**
* Abstract base class that forms the root of the type hierarchy.
*/
class Type: private boost::noncopyable, public std::enable_shared_from_this<Type>
{
public:
enum class Category
{
Integer, IntegerConstant, Bool, Real, Array,
String, Contract, Struct, Function, Enum,
Mapping, Void, TypeType, Modifier, Magic
};
///@{
///@name Factory functions
/// Factory functions that convert an AST @ref TypeName to a Type.
static TypePointer fromElementaryTypeName(Token::Value _typeToken);
static TypePointer fromElementaryTypeName(std::string const& _name);
static TypePointer fromUserDefinedTypeName(UserDefinedTypeName const& _typeName);
static TypePointer fromMapping(ElementaryTypeName& _keyType, TypeName& _valueType);
static TypePointer fromArrayTypeName(TypeName& _baseTypeName, Expression* _length);
/// @}
/// Auto-detect the proper type for a literal. @returns an empty pointer if the literal does
/// not fit any type.
static TypePointer forLiteral(Literal const& _literal);
/// @returns a pointer to _a or _b if the other is implicitly convertible to it or nullptr otherwise
static TypePointer commonType(TypePointer const& _a, TypePointer const& _b);
virtual Category getCategory() const = 0;
virtual bool isImplicitlyConvertibleTo(Type const& _other) const { return *this == _other; }
virtual bool isExplicitlyConvertibleTo(Type const& _convertTo) const
{
return isImplicitlyConvertibleTo(_convertTo);
}
/// @returns the resulting type of applying the given unary operator or an empty pointer if
/// this is not possible.
/// The default implementation does not allow any unary operator.
virtual TypePointer unaryOperatorResult(Token::Value) const { return TypePointer(); }
/// @returns the resulting type of applying the given binary operator or an empty pointer if
/// this is not possible.
/// The default implementation allows comparison operators if a common type exists
virtual TypePointer binaryOperatorResult(Token::Value _operator, TypePointer const& _other) const
{
return Token::isCompareOp(_operator) ? commonType(shared_from_this(), _other) : TypePointer();
}
virtual bool operator==(Type const& _other) const { return getCategory() == _other.getCategory(); }
virtual bool operator!=(Type const& _other) const { return !this->operator ==(_other); }
/// @returns number of bytes used by this type when encoded for CALL, or 0 if the encoding
/// is not a simple big-endian encoding or the type cannot be stored in calldata.
/// Note that irrespective of this size, each calldata element is padded to a multiple of 32 bytes.
virtual unsigned getCalldataEncodedSize() const { return 0; }
/// @returns true if the type is dynamically encoded in calldata
virtual bool isDynamicallySized() const { return false; }
/// @returns number of bytes required to hold this value in storage.
/// For dynamically "allocated" types, it returns the size of the statically allocated head,
virtual u256 getStorageSize() const { return 1; }
/// Returns true if the type can be stored in storage.
virtual bool canBeStored() const { return true; }
/// Returns false if the type cannot live outside the storage, i.e. if it includes some mapping.
virtual bool canLiveOutsideStorage() const { return true; }
/// Returns true if the type can be stored as a value (as opposed to a reference) on the stack,
/// i.e. it behaves differently in lvalue context and in value context.
virtual bool isValueType() const { return false; }
virtual unsigned getSizeOnStack() const { return 1; }
/// @returns the real type of some types, like e.g: IntegerConstant
virtual TypePointer getRealType() const { return shared_from_this(); }
/// Returns the list of all members of this type. Default implementation: no members.
virtual MemberList const& getMembers() const { return EmptyMemberList; }
/// Convenience method, returns the type of the given named member or an empty pointer if no such member exists.
TypePointer getMemberType(std::string const& _name) const { return getMembers().getMemberType(_name); }
virtual std::string toString() const = 0;
virtual u256 literalValue(Literal const*) const
{
BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Literal value requested "
"for type without literals."));
}
protected:
/// Convenience object used when returning an empty member list.
static const MemberList EmptyMemberList;
};
/**
* Any kind of integer type including hash and address.
*/
class IntegerType: public Type
{
public:
enum class Modifier
{
Unsigned, Signed, Hash, Address
};
virtual Category getCategory() const override { return Category::Integer; }
explicit IntegerType(int _bits, Modifier _modifier = Modifier::Unsigned);
virtual bool isImplicitlyConvertibleTo(Type const& _convertTo) const override;
virtual bool isExplicitlyConvertibleTo(Type const& _convertTo) const override;
virtual TypePointer unaryOperatorResult(Token::Value _operator) const override;
virtual TypePointer binaryOperatorResult(Token::Value _operator, TypePointer const& _other) const override;
virtual bool operator==(Type const& _other) const override;
virtual unsigned getCalldataEncodedSize() const override { return m_bits / 8; }
virtual bool isValueType() const override { return true; }
virtual MemberList const& getMembers() const { return isAddress() ? AddressMemberList : EmptyMemberList; }
virtual std::string toString() const override;
int getNumBits() const { return m_bits; }
bool isHash() const { return m_modifier == Modifier::Hash || m_modifier == Modifier::Address; }
bool isAddress() const { return m_modifier == Modifier::Address; }
bool isSigned() const { return m_modifier == Modifier::Signed; }
static const MemberList AddressMemberList;
private:
int m_bits;
Modifier m_modifier;
};
/**
* Integer constants either literals or computed. Example expressions: 2, 2+10, ~10.
* There is one distinct type per value.
*/
class IntegerConstantType: public Type
{
public:
virtual Category getCategory() const override { return Category::IntegerConstant; }
explicit IntegerConstantType(Literal const& _literal);
explicit IntegerConstantType(bigint _value): m_value(_value) {}
virtual bool isImplicitlyConvertibleTo(Type const& _convertTo) const override;
virtual bool isExplicitlyConvertibleTo(Type const& _convertTo) const override;
virtual TypePointer unaryOperatorResult(Token::Value _operator) const override;
virtual TypePointer binaryOperatorResult(Token::Value _operator, TypePointer const& _other) const override;
virtual bool operator==(Type const& _other) const override;
virtual bool canBeStored() const override { return false; }
virtual bool canLiveOutsideStorage() const override { return false; }
virtual unsigned getSizeOnStack() const override { return 1; }
virtual std::string toString() const override;
virtual u256 literalValue(Literal const* _literal) const override;
virtual TypePointer getRealType() const override;
/// @returns the smallest integer type that can hold the value or an empty pointer if not possible.
std::shared_ptr<IntegerType const> getIntegerType() const;
private:
bigint m_value;
};
/**
* String type with fixed length, up to 32 bytes.
*/
class StaticStringType: public Type
{
public:
virtual Category getCategory() const override { return Category::String; }
/// @returns the smallest string type for the given literal or an empty pointer
/// if no type fits.
static std::shared_ptr<StaticStringType> smallestTypeForLiteral(std::string const& _literal);
explicit StaticStringType(int _bytes);
virtual bool isImplicitlyConvertibleTo(Type const& _convertTo) const override;
virtual bool isExplicitlyConvertibleTo(Type const& _convertTo) const override;
virtual bool operator==(Type const& _other) const override;
virtual unsigned getCalldataEncodedSize() const override { return m_bytes; }
virtual bool isValueType() const override { return true; }
virtual std::string toString() const override { return "string" + dev::toString(m_bytes); }
virtual u256 literalValue(Literal const* _literal) const override;
int getNumBytes() const { return m_bytes; }
private:
int m_bytes;
};
/**
* The boolean type.
*/
class BoolType: public Type
{
public:
BoolType() {}
virtual Category getCategory() const override { return Category::Bool; }
virtual bool isExplicitlyConvertibleTo(Type const& _convertTo) const override;
virtual TypePointer unaryOperatorResult(Token::Value _operator) const override;
virtual TypePointer binaryOperatorResult(Token::Value _operator, TypePointer const& _other) const override;
virtual unsigned getCalldataEncodedSize() const { return 1; }
virtual bool isValueType() const override { return true; }
virtual std::string toString() const override { return "bool"; }
virtual u256 literalValue(Literal const* _literal) const override;
};
/**
* The type of an array. The flavours are byte array (bytes), statically- (<type>[<length>])
* and dynamically-sized array (<type>[]).
*/
class ArrayType: public Type
{
public:
enum class Location { Storage, CallData, Memory };
virtual Category getCategory() const override { return Category::Array; }
/// Constructor for a byte array ("bytes")
explicit ArrayType(Location _location):
m_location(_location), m_isByteArray(true), m_baseType(std::make_shared<IntegerType>(8)) {}
/// Constructor for a dynamically sized array type ("type[]")
ArrayType(Location _location, const TypePointer &_baseType):
m_location(_location), m_baseType(_baseType) {}
/// Constructor for a fixed-size array type ("type[20]")
ArrayType(Location _location, const TypePointer &_baseType, u256 const& _length):
m_location(_location), m_baseType(_baseType), m_hasDynamicLength(false), m_length(_length) {}
virtual bool isImplicitlyConvertibleTo(Type const& _convertTo) const override;
virtual TypePointer unaryOperatorResult(Token::Value _operator) const override;
virtual bool operator==(const Type& _other) const override;
virtual bool isDynamicallySized() const { return m_hasDynamicLength; }
virtual u256 getStorageSize() const override;
virtual unsigned getSizeOnStack() const override;
virtual std::string toString() const override;
virtual MemberList const& getMembers() const override { return s_arrayTypeMemberList; }
Location getLocation() const { return m_location; }
bool isByteArray() const { return m_isByteArray; }
TypePointer const& getBaseType() const { solAssert(!!m_baseType, ""); return m_baseType;}
u256 const& getLength() const { return m_length; }
/// @returns a copy of this type with location changed to @a _location
/// @todo this might move as far up as Type later
std::shared_ptr<ArrayType> copyForLocation(Location _location) const;
private:
Location m_location;
bool m_isByteArray = false; ///< Byte arrays ("bytes") have different semantics from ordinary arrays.
TypePointer m_baseType;
bool m_hasDynamicLength = true;
u256 m_length;
static const MemberList s_arrayTypeMemberList;
};
/**
* The type of a contract instance, there is one distinct type for each contract definition.
*/
class ContractType: public Type
{
public:
virtual Category getCategory() const override { return Category::Contract; }
explicit ContractType(ContractDefinition const& _contract, bool _super = false):
m_contract(_contract), m_super(_super) {}
/// Contracts can be implicitly converted to super classes and to addresses.
virtual bool isImplicitlyConvertibleTo(Type const& _convertTo) const override;
/// Contracts can be converted to themselves and to integers.
virtual bool isExplicitlyConvertibleTo(Type const& _convertTo) const override;
virtual TypePointer unaryOperatorResult(Token::Value _operator) const override;
virtual bool operator==(Type const& _other) const override;
virtual bool isValueType() const override { return true; }
virtual std::string toString() const override;
virtual MemberList const& getMembers() const override;
bool isSuper() const { return m_super; }
ContractDefinition const& getContractDefinition() const { return m_contract; }
/// Returns the function type of the constructor. Note that the location part of the function type
/// is not used, as this type cannot be the type of a variable or expression.
FunctionTypePointer const& getConstructorType() const;
/// @returns the identifier of the function with the given name or Invalid256 if such a name does
/// not exist.
u256 getFunctionIdentifier(std::string const& _functionName) const;
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;
/// Type of the constructor, @see getConstructorType. Lazily initialized.
mutable FunctionTypePointer m_constructorType;
/// List of member types, will be lazy-initialized because of recursive references.
mutable std::unique_ptr<MemberList> m_members;
};
/**
* The type of a struct instance, there is one distinct type per struct definition.
*/
class StructType: public Type
{
public:
virtual Category getCategory() const override { return Category::Struct; }
explicit StructType(StructDefinition const& _struct): m_struct(_struct) {}
virtual TypePointer unaryOperatorResult(Token::Value _operator) const override;
virtual bool operator==(Type const& _other) const override;
virtual u256 getStorageSize() const override;
virtual bool canLiveOutsideStorage() const override;
virtual unsigned getSizeOnStack() const override { return 1; /*@todo*/ }
virtual std::string toString() const override;
virtual MemberList const& getMembers() const override;
u256 getStorageOffsetOfMember(std::string const& _name) const;
private:
StructDefinition const& m_struct;
/// List of member types, will be lazy-initialized because of recursive references.
mutable std::unique_ptr<MemberList> m_members;
};
/**
* The type of an enum instance, there is one distinct type per enum definition.
*/
class EnumType: public Type
{
public:
virtual Category getCategory() const override { return Category::Enum; }
explicit EnumType(EnumDefinition const& _enum): m_enum(_enum) {}
virtual TypePointer unaryOperatorResult(Token::Value _operator) const override;
virtual bool operator==(Type const& _other) const override;
virtual unsigned getSizeOnStack() const override { return 1; }
virtual std::string toString() const override;
virtual bool isValueType() const override { return true; }
virtual bool isExplicitlyConvertibleTo(Type const& _convertTo) const override;
EnumDefinition const& getEnumDefinition() const { return m_enum; }
/// @returns the value that the string has in the Enum
unsigned int getMemberValue(ASTString const& _member) const;
private:
EnumDefinition const& m_enum;
/// List of member types, will be lazy-initialized because of recursive references.
mutable std::unique_ptr<MemberList> m_members;
};
/**
* The type of a function, identified by its (return) parameter types.
* @todo the return parameters should also have names, i.e. return parameters should be a struct
* type.
*/
class FunctionType: public Type
{
public:
/// The meaning of the value(s) on the stack referencing the function:
/// INTERNAL: jump tag, EXTERNAL: contract address + function identifier,
/// BARE: contract address (non-abi contract call)
/// OTHERS: special virtual function, nothing on the stack
/// @todo This documentation is outdated, and Location should rather be named "Type"
enum class Location { Internal, External, Creation, Send,
SHA3, Suicide,
ECRecover, SHA256, RIPEMD160,
Log0, Log1, Log2, Log3, Log4, Event,
SetGas, SetValue, BlockHash,
Bare };
virtual Category getCategory() const override { return Category::Function; }
explicit FunctionType(FunctionDefinition const& _function, bool _isInternal = true);
explicit FunctionType(VariableDeclaration const& _varDecl);
explicit FunctionType(EventDefinition const& _event);
FunctionType(strings const& _parameterTypes, strings const& _returnParameterTypes,
Location _location = Location::Internal, bool _arbitraryParameters = false):
FunctionType(parseElementaryTypeVector(_parameterTypes), parseElementaryTypeVector(_returnParameterTypes),
_location, _arbitraryParameters) {}
FunctionType(
TypePointers const& _parameterTypes,
TypePointers const& _returnParameterTypes,
Location _location = Location::Internal,
bool _arbitraryParameters = false,
bool _gasSet = false,
bool _valueSet = false
):
m_parameterTypes (_parameterTypes),
m_returnParameterTypes (_returnParameterTypes),
m_location (_location),
m_arbitraryParameters (_arbitraryParameters),
m_gasSet (_gasSet),
m_valueSet (_valueSet)
{}
TypePointers const& getParameterTypes() const { return m_parameterTypes; }
std::vector<std::string> const& getParameterNames() const { return m_parameterNames; }
std::vector<std::string> const getParameterTypeNames() const;
TypePointers const& getReturnParameterTypes() const { return m_returnParameterTypes; }
std::vector<std::string> const& getReturnParameterNames() const { return m_returnParameterNames; }
std::vector<std::string> const getReturnParameterTypeNames() const;
virtual bool operator==(Type const& _other) const override;
virtual std::string toString() const override;
virtual bool canBeStored() const override { return false; }
virtual u256 getStorageSize() const override { BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Storage size of non-storable function type requested.")); }
virtual bool canLiveOutsideStorage() const override { return false; }
virtual unsigned getSizeOnStack() const override;
virtual MemberList const& getMembers() const override;
Location const& getLocation() const { return m_location; }
/// @returns the canonical signature of this function type given the function name
/// If @a _name is not provided (empty string) then the @c m_declaration member of the
/// function type is used
std::string getCanonicalSignature(std::string const& _name = "") const;
Declaration const& getDeclaration() const
{
solAssert(m_declaration, "Requested declaration from a FunctionType that has none");
return *m_declaration;
}
bool hasDeclaration() const { return !!m_declaration; }
bool isConstant() const { return m_isConstant; }
/// @return A shared pointer of an ASTString.
/// Can contain a nullptr in which case indicates absence of documentation
ASTPointer<ASTString> getDocumentation() const;
/// true iff arguments are to be padded to multiples of 32 bytes for external calls
bool padArguments() const { return !(m_location == Location::SHA3 || m_location == Location::SHA256 || m_location == Location::RIPEMD160); }
bool takesArbitraryParameters() const { return m_arbitraryParameters; }
bool gasSet() const { return m_gasSet; }
bool valueSet() const { return m_valueSet; }
/// @returns a copy of this type, where gas or value are set manually. This will never set one
/// of the parameters to fals.
TypePointer copyAndSetGasOrValue(bool _setGas, bool _setValue) const;
private:
static TypePointers parseElementaryTypeVector(strings const& _types);
TypePointers m_parameterTypes;
TypePointers m_returnParameterTypes;
std::vector<std::string> m_parameterNames;
std::vector<std::string> m_returnParameterNames;
Location const m_location;
/// true iff the function takes an arbitrary number of arguments of arbitrary types
bool const m_arbitraryParameters = false;
bool const m_gasSet = false; ///< true iff the gas value to be used is on the stack
bool const m_valueSet = false; ///< true iff the value to be sent is on the stack
bool m_isConstant = false;
mutable std::unique_ptr<MemberList> m_members;
Declaration const* m_declaration = nullptr;
};
/**
* The type of a mapping, there is one distinct type per key/value type pair.
*/
class MappingType: public Type
{
public:
virtual Category getCategory() const override { return Category::Mapping; }
MappingType(TypePointer const& _keyType, TypePointer const& _valueType):
m_keyType(_keyType), m_valueType(_valueType) {}
virtual bool operator==(Type const& _other) const override;
virtual std::string toString() const override;
virtual bool canLiveOutsideStorage() const override { return false; }
TypePointer const& getKeyType() const { return m_keyType; }
TypePointer const& getValueType() const { return m_valueType; }
private:
TypePointer m_keyType;
TypePointer m_valueType;
};
/**
* The void type, can only be implicitly used as the type that is returned by functions without
* return parameters.
*/
class VoidType: public Type
{
public:
virtual Category getCategory() const override { return Category::Void; }
VoidType() {}
virtual TypePointer binaryOperatorResult(Token::Value, TypePointer const&) const override { return TypePointer(); }
virtual std::string toString() const override { return "void"; }
virtual bool canBeStored() const override { return false; }
virtual u256 getStorageSize() const override { BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Storage size of non-storable void type requested.")); }
virtual bool canLiveOutsideStorage() const override { return false; }
virtual unsigned getSizeOnStack() const override { return 0; }
};
/**
* The type of a type reference. The type of "uint32" when used in "a = uint32(2)" is an example
* of a TypeType.
*/
class TypeType: public Type
{
public:
virtual Category getCategory() const override { return Category::TypeType; }
explicit TypeType(TypePointer const& _actualType, ContractDefinition const* _currentContract = nullptr):
m_actualType(_actualType), m_currentContract(_currentContract) {}
TypePointer const& getActualType() const { return m_actualType; }
virtual TypePointer binaryOperatorResult(Token::Value, TypePointer const&) const override { return TypePointer(); }
virtual bool operator==(Type const& _other) const override;
virtual bool canBeStored() const override { return false; }
virtual u256 getStorageSize() const override { BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Storage size of non-storable type type requested.")); }
virtual bool canLiveOutsideStorage() const override { return false; }
virtual unsigned getSizeOnStack() const override { return 0; }
virtual std::string toString() const override { return "type(" + m_actualType->toString() + ")"; }
virtual MemberList const& getMembers() const override;
private:
TypePointer m_actualType;
/// Context in which this type is used (influences visibility etc.), can be nullptr.
ContractDefinition const* m_currentContract;
/// List of member types, will be lazy-initialized because of recursive references.
mutable std::unique_ptr<MemberList> m_members;
};
/**
* The type of a function modifier. Not used for anything for now.
*/
class ModifierType: public Type
{
public:
virtual Category getCategory() const override { return Category::Modifier; }
explicit ModifierType(ModifierDefinition const& _modifier);
virtual TypePointer binaryOperatorResult(Token::Value, TypePointer const&) const override { return TypePointer(); }
virtual bool canBeStored() const override { return false; }
virtual u256 getStorageSize() const override { BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Storage size of non-storable type type requested.")); }
virtual bool canLiveOutsideStorage() const override { return false; }
virtual unsigned getSizeOnStack() const override { return 0; }
virtual bool operator==(Type const& _other) const override;
virtual std::string toString() const override;
private:
TypePointers m_parameterTypes;
};
/**
* Special type for magic variables (block, msg, tx), similar to a struct but without any reference
* (it always references a global singleton by name).
*/
class MagicType: public Type
{
public:
enum class Kind { Block, Message, Transaction };
virtual Category getCategory() const override { return Category::Magic; }
explicit MagicType(Kind _kind);
virtual TypePointer binaryOperatorResult(Token::Value, TypePointer const&) const override
{
return TypePointer();
}
virtual bool operator==(Type const& _other) const;
virtual bool canBeStored() const override { return false; }
virtual bool canLiveOutsideStorage() const override { return true; }
virtual unsigned getSizeOnStack() const override { return 0; }
virtual MemberList const& getMembers() const override { return m_members; }
virtual std::string toString() const override;
private:
Kind m_kind;
MemberList m_members;
};
}
}