Model of an Ethereum state, essentially a facade for the trie. More...

#include <State.h>

Inheritance diagram for dev::eth::State:

Collaboration diagram for dev::eth::State:

Public Types
enum	CommitBehaviour { CommitBehaviour::KeepEmptyAccounts, CommitBehaviour::RemoveEmptyAccounts }

enum	NullType { Null }

Public Member Functions
	State (u256 const &_accountStartNonce)
	Default constructor; creates with a blank database prepopulated with the genesis block. More...

	State (u256 const &_accountStartNonce, OverlayDB const &_db, BaseState _bs=BaseState::PreExisting)
	Basic state object from database. More...

	State (NullType)

	State (State const &_s)
	Copy state object. More...

State &	operator= (State const &_s)
	Copy state object. More...

OverlayDB const &	db () const

OverlayDB &	db ()

void	populateFrom (AccountMap const &_map)
	Populate the state from the given AccountMap. Just uses dev::eth::commit(). More...

std::unordered_map< Address, u256 >	addresses () const

std::pair< ExecutionResult, TransactionReceipt >	execute (EnvInfo const &_envInfo, SealEngineFace const &_sealEngine, Transaction const &_t, Permanence _p=Permanence::Committed, OnOpFunc const &_onOp=OnOpFunc())
	Execute a given transaction. More...

bool	addressInUse (Address const &_address) const
	Check if the address is in use. More...

bool	accountNonemptyAndExisting (Address const &_address) const
	Check if the account exists in the state and is non empty (nonce > 0 \|\| balance > 0 \|\| code nonempty). More...

bool	addressHasCode (Address const &_address) const
	Check if the address contains executable code. More...

u256	balance (Address const &_id) const
	Get an account's balance. More...

virtual void	addBalance (Address const &_id, u256 const &_amount)
	Add some amount to balance. More...

void	subBalance (Address const &_addr, u256 const &_value)
	Subtract the `_value` amount from the balance of `_addr` account. More...

virtual void	transferBalance (Address const &_from, Address const &_to, u256 const &_value)
	Transfers "the balance _value between two accounts. More...

h256	storageRoot (Address const &_contract) const
	Get the root of the storage of an account. More...

u256	storage (Address const &_contract, u256 const &_memory) const
	Get the value of a storage position of an account. More...

void	setStorage (Address const &_contract, u256 const &_location, u256 const &_value)
	Set the value of a storage position of an account. More...

void	createContract (Address const &_address)
	Create a contract at the given address (with unset code and unchanged balance). More...

void	setNewCode (Address const &_address, bytes &&_code)
	Sets the code of the account. Must only be called during / after contract creation. More...

virtual void	kill (Address _a)
	Delete an account (used for processing suicides). More...

std::map< h256, std::pair< u256, u256 > >	storage (Address const &_contract) const
	Get the storage of an account. More...

bytes const &	code (Address const &_addr) const
	Get the code of an account. More...

h256	codeHash (Address const &_contract) const
	Get the code hash of an account. More...

size_t	codeSize (Address const &_contract) const
	Get the byte-size of the code of an account. More...

void	incNonce (Address const &_id)
	Increament the account nonce. More...

u256	getNonce (Address const &_addr) const
	Get the account nonce – the number of transactions it has sent. More...

h256	rootHash () const
	The hash of the root of our state tree. More...

void	commit (CommitBehaviour _commitBehaviour)
	Commit all changes waiting in the address cache to the DB. More...

void	setRoot (h256 const &_root)
	Resets any uncommitted changes to the cache. More...

u256 const &	accountStartNonce () const
	Get the account start nonce. May be required. More...

u256 const &	requireAccountStartNonce () const

void	noteAccountStartNonce (u256 const &_actual)

size_t	savepoint () const
	Create a savepoint in the state changelog. More...

void	rollback (size_t _savepoint)
	Revert all recent changes up to the given `_savepoint` savepoint. More...

virtual	~State ()

Static Public Member Functions
static OverlayDB	openDB (std::string const &_path, h256 const &_genesisHash, WithExisting _we=WithExisting::Trust)
	Open a DB - useful for passing into the constructor & keeping for other states that are necessary. More...

Protected Member Functions
void	removeEmptyAccounts ()
	Turns all "touched" empty accounts into non-alive accounts. More...

Account const *	account (Address const &_addr) const

Account *	account (Address const &_addr)

void	clearCacheIfTooLarge () const
	Purges non-modified entries in m_cache if it grows too large. More...

void	createAccount (Address const &_address, Account const &&_account)

Protected Attributes
OverlayDB	m_db
	Our overlay for the state tree. More...

SecureTrieDB< Address, OverlayDB >	m_state
	Our state tree, as an OverlayDB DB. More...

std::unordered_map< Address, Account >	m_cache
	Our address cache. This stores the states of each address that has (or at least might have) been changed. More...

std::vector< Address >	m_unchangedCacheEntries
	Tracks entries in m_cache that can potentially be purged if it grows too large. More...

std::set< Address >	m_nonExistingAccountsCache
	Tracks addresses that are known to not exist. More...

AddressHash	m_touched
	Tracks all addresses touched so far. More...

u256	m_accountStartNonce

std::vector< detail::Change >	m_changeLog

Friends
class	ExtVM

class	dev::test::ImportTest

class	dev::test::StateLoader

class	BlockChain

std::ostream &	operator<< (std::ostream &_out, State const &_s)

Detailed Description

Model of an Ethereum state, essentially a facade for the trie.

Allows you to query the state of accounts as well as creating and modifying accounts. It has built-in caching for various aspects of the state.

State Changelog

Any atomic change to any account is registered and appended in the changelog. In case some changes must be reverted, the changes are popped from the changelog and undone. For possible atomic changes list

See also: Change::Kind. The changelog is managed by savepoint(), rollback() and commit() methods.

Definition at line 161 of file State.h.

Member Enumeration Documentation

enum dev::eth::State::CommitBehaviour

strong

Enumerator
KeepEmptyAccounts
RemoveEmptyAccounts

Definition at line 169 of file State.h.

enum dev::eth::State::NullType

Enumerator
Null

Definition at line 184 of file State.h.

Constructor & Destructor Documentation

dev::eth::State::State ( u256 const & _accountStartNonce )

inlineexplicit

Default constructor; creates with a blank database prepopulated with the genesis block.

Definition at line 176 of file State.h.

State::State	(	u256 const &	_accountStartNonce,
		OverlayDB const &	_db,
		BaseState	_bs = `BaseState::PreExisting`
	)

explicit

Basic state object from database.

Use the default when you already have a database and you just want to make a State object which uses it. If you have no preexisting database then set BaseState to something other than BaseState::PreExisting in order to prepopulate the Trie.

Definition at line 54 of file State.cpp.

dev::eth::State::State ( NullType )

inline

Definition at line 185 of file State.h.

State::State ( State const & _s )

Copy state object.

Definition at line 64 of file State.cpp.

virtual dev::eth::State::~State ( )

inlinevirtual

Definition at line 309 of file State.h.

Member Function Documentation

Account const * State::account ( Address const & _addr ) const

protected

Returns: the account at the given address or a null pointer if it does not exist. The pointer is valid until the next access to the state or account.

Definition at line 158 of file State.cpp.

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Account * State::account ( Address const & _addr )

protected

Returns: the account at the given address or a null pointer if it does not exist. The pointer is valid until the next access to the state or account.

Definition at line 163 of file State.cpp.

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bool State::accountNonemptyAndExisting ( Address const & _address ) const

Check if the account exists in the state and is non empty (nonce > 0 || balance > 0 || code nonempty).

These two notions are equivalent after EIP158.

Definition at line 250 of file State.cpp.

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u256 const& dev::eth::State::accountStartNonce ( ) const

inline

Get the account start nonce. May be required.

Definition at line 298 of file State.h.

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void State::addBalance	(	Address const &	_id,
		u256 const &	_amount
	)

virtual

Add some amount to balance.

Will initialise the address if it has never been used.

Reimplemented in FascState.

Definition at line 286 of file State.cpp.

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unordered_map< Address, u256 > State::addresses ( ) const

Returns: the set containing all addresses currently in use in Ethereum.

Warning: This is slowslowslow. Don't use it unless you want to lock the object for seconds or minutes at a time.

Exceptions

InterfaceNotSupported if compiled without ETH_FATDB.

Definition at line 220 of file State.cpp.

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bool State::addressHasCode ( Address const & _address ) const

Check if the address contains executable code.

Definition at line 258 of file State.cpp.

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bool State::addressInUse ( Address const & _address ) const

Check if the address is in use.

Definition at line 245 of file State.cpp.

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u256 State::balance ( Address const & _id ) const

Get an account's balance.

Returns: 0 if the address has never been used.

Definition at line 266 of file State.cpp.

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void State::clearCacheIfTooLarge ( ) const

protected

Purges non-modified entries in m_cache if it grows too large.

Definition at line 192 of file State.cpp.

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bytes const & State::code ( Address const & _addr ) const

Get the code of an account.

Returns: bytes() if no account exists at that address.

Warning: The reference to the code is only valid until the access to other account. Do not keep it.

Definition at line 423 of file State.cpp.

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h256 State::codeHash ( Address const & _contract ) const

Get the code hash of an account.

Returns: EmptySHA3 if no account exists at that address or if there is no code associated with the address.

Definition at line 446 of file State.cpp.

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size_t State::codeSize ( Address const & _contract ) const

Get the byte-size of the code of an account.

Returns: code(_contract).size(), but utilizes CodeSizeHash.

Definition at line 454 of file State.cpp.

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void State::commit ( CommitBehaviour _commitBehaviour )

Commit all changes waiting in the address cache to the DB.

Parameters

_commitBehaviour whether or not to remove empty accounts during commit.

Definition at line 210 of file State.cpp.

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void State::createAccount	(	Address const &	_address,
		Account const &&	_account
	)

protected

Definition at line 330 of file State.cpp.

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void State::createContract ( Address const & _address )

Create a contract at the given address (with unset code and unchanged balance).

Definition at line 325 of file State.cpp.

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OverlayDB const& dev::eth::State::db ( ) const

inline

Definition at line 195 of file State.h.

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OverlayDB& dev::eth::State::db ( )

inline

Definition at line 196 of file State.h.

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std::pair< ExecutionResult, TransactionReceipt > State::execute	(	EnvInfo const &	_envInfo,
		SealEngineFace const &	_sealEngine,
		Transaction const &	_t,
		Permanence	_p = `Permanence::Committed`,
		OnOpFunc const &	_onOp = `OnOpFunc()`
	)

Execute a given transaction.

This will change the state accordingly.

Definition at line 515 of file State.cpp.

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u256 State::getNonce ( Address const & _addr ) const

Get the account nonce – the number of transactions it has sent.

Returns: 0 if the address has never been used.

Definition at line 345 of file State.cpp.

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void State::incNonce ( Address const & _id )

Increament the account nonce.

Definition at line 274 of file State.cpp.

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void State::kill ( Address _a )

virtual

Delete an account (used for processing suicides).

Reimplemented in FascState.

Definition at line 338 of file State.cpp.

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void State::noteAccountStartNonce ( u256 const & _actual )

Definition at line 128 of file State.cpp.

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OverlayDB State::openDB	(	std::string const &	_path,
		h256 const &	_genesisHash,
		WithExisting	_we = `WithExisting::Trust`
	)

static

Open a DB - useful for passing into the constructor & keeping for other states that are necessary.

Definition at line 74 of file State.cpp.

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State & State::operator= ( State const & _s )

Copy state object.

Definition at line 143 of file State.cpp.

void State::populateFrom ( AccountMap const & _map )

Populate the state from the given AccountMap. Just uses dev::eth::commit().

Definition at line 115 of file State.cpp.

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void State::removeEmptyAccounts ( )

protected

Turns all "touched" empty accounts into non-alive accounts.

Definition at line 136 of file State.cpp.

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u256 const & State::requireAccountStartNonce ( ) const

Definition at line 121 of file State.cpp.

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void State::rollback ( size_t _savepoint )

Revert all recent changes up to the given _savepoint savepoint.

Definition at line 480 of file State.cpp.

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h256 dev::eth::State::rootHash ( ) const

inline

The hash of the root of our state tree.

Definition at line 288 of file State.h.

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size_t State::savepoint ( ) const

Create a savepoint in the state changelog.

///

Returns: The savepoint index that can be used in rollback() function.

Definition at line 475 of file State.cpp.

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void State::setNewCode	(	Address const &	_address,
		bytes &&	_code
	)

Sets the code of the account. Must only be called during / after contract creation.

Definition at line 440 of file State.cpp.

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void State::setRoot ( h256 const & _root )

Resets any uncommitted changes to the cache.

Definition at line 236 of file State.cpp.

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void State::setStorage	(	Address const &	_contract,
		u256 const &	_location,
		u256 const &	_value
	)

Set the value of a storage position of an account.

Definition at line 372 of file State.cpp.

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u256 State::storage	(	Address const &	_contract,
		u256 const &	_memory
	)		const

Get the value of a storage position of an account.

Returns: 0 if no account exists at that address.

Definition at line 353 of file State.cpp.

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map< h256, pair< u256, u256 > > State::storage ( Address const & _contract ) const

Get the storage of an account.

Note: This is expensive. Don't use it unless you need to.

Returns: map of hashed keys to key-value pairs or empty map if no account exists at that address.

Definition at line 378 of file State.cpp.

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h256 State::storageRoot ( Address const & _contract ) const

Get the root of the storage of an account.

Definition at line 412 of file State.cpp.

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void State::subBalance	(	Address const &	_addr,
		u256 const &	_value
	)

Subtract the _value amount from the balance of _addr account.

Exceptions

NotEnoughCash if the balance of the account is less than the amount to be subtrackted (also in case the account does not exist).

Definition at line 311 of file State.cpp.

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virtual void dev::eth::State::transferBalance	(	Address const &	_from,
		Address const &	_to,
		u256 const &	_value
	)

inlinevirtual

Transfers "the balance _value between two accounts.

Parameters

_from	Account from which _value will be deducted.
_to	Account to which _value will be added.
_value	Amount to be transferred.

Reimplemented in FascState.

Definition at line 240 of file State.h.

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Friends And Related Function Documentation

friend class BlockChain

friend

Definition at line 166 of file State.h.

friend class dev::test::ImportTest

friend

Definition at line 164 of file State.h.

friend class dev::test::StateLoader

friend

Definition at line 165 of file State.h.

friend class ExtVM

friend

Definition at line 163 of file State.h.

std::ostream& operator<<	(	std::ostream &	_out,
		State const &	_s
	)

friend

Member Data Documentation

u256 dev::eth::State::m_accountStartNonce

protected

Definition at line 336 of file State.h.

std::unordered_map<Address, Account> dev::eth::State::m_cache

mutableprotected

Our address cache. This stores the states of each address that has (or at least might have) been changed.

Definition at line 331 of file State.h.

std::vector<detail::Change> dev::eth::State::m_changeLog

protected

Definition at line 339 of file State.h.

OverlayDB dev::eth::State::m_db

protected

Our overlay for the state tree.

Definition at line 329 of file State.h.

std::set<Address> dev::eth::State::m_nonExistingAccountsCache

mutableprotected

Tracks addresses that are known to not exist.

Definition at line 333 of file State.h.

SecureTrieDB<Address, OverlayDB> dev::eth::State::m_state

protected

Our state tree, as an OverlayDB DB.

Definition at line 330 of file State.h.

AddressHash dev::eth::State::m_touched

protected

Tracks all addresses touched so far.

Definition at line 334 of file State.h.

std::vector<Address> dev::eth::State::m_unchangedCacheEntries

mutableprotected

Tracks entries in m_cache that can potentially be purged if it grows too large.

Definition at line 332 of file State.h.

The documentation for this class was generated from the following files:

src/cpp-ethereum/libethereum/State.h
src/cpp-ethereum/libethereum/State.cpp

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Protected Attributes

Friends

Detailed Description

State Changelog

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Friends And Related Function Documentation

Member Data Documentation