path: root/state/managed_state.go

package state

import "sync"

type account struct {
    stateObject *StateObject
    nstart      uint64
    nonces      []bool
}

type ManagedState struct {
    *StateDB

    mu sync.RWMutex

    accounts map[string]*account
}

func ManageState(statedb *StateDB) *ManagedState {
    return &ManagedState{
        StateDB:  statedb,
        accounts: make(map[string]*account),
    }
}

func (ms *ManagedState) SetState(statedb *StateDB) {
    ms.mu.Lock()
    defer ms.mu.Unlock()
    ms.StateDB = statedb
}

func (ms *ManagedState) RemoveNonce(addr []byte, n uint64) {
    if ms.hasAccount(addr) {
        ms.mu.Lock()
        defer ms.mu.Unlock()

        account := ms.getAccount(addr)
        if n-account.nstart <= uint64(len(account.nonces)) {
            reslice := make([]bool, n-account.nstart)
            copy(reslice, account.nonces[:n-account.nstart])
            account.nonces = reslice
        }
    }
}

func (ms *ManagedState) NewNonce(addr []byte) uint64 {
    ms.mu.RLock()
    defer ms.mu.RUnlock()

    account := ms.getAccount(addr)
    for i, nonce := range account.nonces {
        if !nonce {
            return account.nstart + uint64(i)
        }
    }
    account.nonces = append(account.nonces, true)
    return uint64(len(account.nonces)) + account.nstart
}

func (ms *ManagedState) hasAccount(addr []byte) bool {
    _, ok := ms.accounts[string(addr)]
    return ok
}

func (ms *ManagedState) getAccount(addr []byte) *account {
    if account, ok := ms.accounts[string(addr)]; !ok {
        so := ms.GetOrNewStateObject(addr)
        ms.accounts[string(addr)] = newAccount(so)
    } else {
        // Always make sure the state account nonce isn't actually higher
        // than the tracked one.
        so := ms.StateDB.GetStateObject(addr)
        if so != nil && uint64(len(account.nonces))+account.nstart < so.nonce {
            ms.accounts[string(addr)] = newAccount(so)
        }

    }

    return ms.accounts[string(addr)]
}

func newAccount(so *StateObject) *account {
    return &account{so, so.nonce - 1, nil}
}