Struct cita_state::State

pub struct State<B> {
    pub db: B,
    pub root: H256,
    pub cache: RefCell<HashMap<Address, StateObjectEntry>>,
    pub checkpoints: RefCell<Vec<HashMap<Address, Option<StateObjectEntry>>>>,
}

State is the one who managers all accounts and states in Ethereum's system.

Fields

db: B

root: H256

cache: RefCell<HashMap<Address, StateObjectEntry>>

checkpoints: RefCell<Vec<HashMap<Address, Option<StateObjectEntry>>>>

Checkpoints are used to revert to history.

Methods

impl<B: DB> State<B>

pub fn new(db: B) -> Result<State<B>, Error>

Creates empty state for test.

pub fn from_existing(db: B, root: H256) -> Result<State<B>, Error>

Creates new state with existing state root

pub fn new_contract(
    &mut self,
    contract: &Address,
    balance: U256,
    nonce: U256,
    code: Vec<u8>
) -> StateObject

Create a contract account with code or not Overwrite the code if the contract already exists

pub fn kill_contract(&mut self, contract: &Address)

Kill a contract.

pub fn kill_garbage(&mut self, inused: &HashSet<Address>)

Remove any touched empty or dust accounts.

pub fn clear(&mut self)

Clear cache Note that the cache is just a HashMap, so memory explosion will be happend if you never call clear(). You should decide for yourself when to call this function.

pub fn get_state_object(
    &mut self,
    address: &Address
) -> Result<Option<StateObject>, Error>

Get state object.

pub fn get_state_object_or_default(
    &mut self,
    address: &Address
) -> Result<StateObject, Error>

Get state object. If not exists, create a fresh one.

pub fn exist(&mut self, address: &Address) -> Result<bool, Error>

Check if an account exists.

pub fn is_empty(&mut self, address: &Address) -> Result<bool, Error>

Check if an account is empty. Empty is defined according to EIP161 (balance = nonce = code = 0).

pub fn set_storage(
    &mut self,
    address: &Address,
    key: H256,
    value: H256
) -> Result<(), Error>

Set (key, value) in storage cache.

pub fn set_code(
    &mut self,
    address: &Address,
    code: Vec<u8>
) -> Result<(), Error>

Set code for an account.

pub fn add_balance(
    &mut self,
    address: &Address,
    incr: U256
) -> Result<(), Error>

Add balance by incr for an account.

pub fn sub_balance(&mut self, a: &Address, decr: U256) -> Result<(), Error>

Sub balance by decr for an account.

pub fn transfer_balance(
    &mut self,
    from: &Address,
    to: &Address,
    by: U256
) -> Result<(), Error>

Transfer balance from from to to by by.

pub fn inc_nonce(&mut self, address: &Address) -> Result<(), Error>

Increase nonce for an account.

pub fn commit(&mut self) -> Result<(), Error>

Flush the data from cache to database.

pub fn checkpoint(&mut self) -> usize

Create a recoverable checkpoint of this state. Return the checkpoint index.

pub fn discard_checkpoint(&mut self)

Merge last checkpoint with previous.

pub fn revert_checkpoint(&mut self)

Revert to the last checkpoint and discard it.

Trait Implementations

impl<B: DB> StateObjectInfo for State<B>

fn nonce(&mut self, a: &Address) -> Result<U256, Error>

fn balance(&mut self, a: &Address) -> Result<U256, Error>

fn get_storage(&mut self, a: &Address, key: &H256) -> Result<H256, Error>

fn code(&mut self, a: &Address) -> Result<Vec<u8>, Error>

fn code_hash(&mut self, a: &Address) -> Result<H256, Error>

fn code_size(&mut self, a: &Address) -> Result<usize, Error>