go-ethereum/core/state/statedb.go

// Copyright 2014 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library 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 Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

// Package state provides a caching layer atop the Ethereum state trie.
package state

import (
	"fmt"
	"maps"
	"math/big"
	"slices"
	"sort"
	"time"

	"github.com/XinFinOrg/XDPoSChain/common"
	"github.com/XinFinOrg/XDPoSChain/core/rawdb"
	"github.com/XinFinOrg/XDPoSChain/core/tracing"
	"github.com/XinFinOrg/XDPoSChain/core/types"
	"github.com/XinFinOrg/XDPoSChain/crypto"
	"github.com/XinFinOrg/XDPoSChain/log"
	"github.com/XinFinOrg/XDPoSChain/params"
	"github.com/XinFinOrg/XDPoSChain/rlp"
	"github.com/XinFinOrg/XDPoSChain/trie"
)

type revision struct {
	id           int
	journalIndex int
}

// StateDB structs within the ethereum protocol are used to store anything
// within the merkle trie. StateDBs take care of caching and storing
// nested states. It's the general query interface to retrieve:
// * Contracts
// * Accounts
type StateDB struct {
	db   Database
	trie Trie

	// originalRoot is the pre-state root, before any changes were made.
	// It will be updated when the Commit is called.
	originalRoot common.Hash

	// This map holds 'live' objects, which will get modified while processing a state transition.
	stateObjects         map[common.Address]*stateObject
	stateObjectsPending  map[common.Address]struct{} // State objects finalized but not yet written to the trie
	stateObjectsDirty    map[common.Address]struct{} // State objects modified in the current execution
	stateObjectsDestruct map[common.Address]struct{} // State objects destructed in the block

	// DB error.
	// State objects are used by the consensus core and VM which are
	// unable to deal with database-level errors. Any error that occurs
	// during a database read is memoized here and will eventually be
	// returned by StateDB.Commit. Notably, this error is also shared
	// by all cached state objects in case the database failure occurs
	// when accessing state of accounts.
	dbErr error

	// The refund counter, also used by state transitioning.
	refund uint64

	thash   common.Hash
	txIndex int
	logs    map[common.Hash][]*types.Log
	logSize uint

	preimages map[common.Hash][]byte

	// Per-transaction access list
	accessList *accessList

	// Transient storage
	transientStorage transientStorage

	// Journal of state modifications. This is the backbone of
	// Snapshot and RevertToSnapshot.
	journal        *journal
	validRevisions []revision
	nextRevisionId int

	// Measurements gathered during execution for debugging purposes
	AccountReads   time.Duration
	AccountHashes  time.Duration
	AccountUpdates time.Duration
	AccountCommits time.Duration
	StorageReads   time.Duration
	StorageHashes  time.Duration
	StorageUpdates time.Duration
	StorageCommits time.Duration
	TrieDBCommits  time.Duration

	AccountUpdated int
	StorageUpdated int
	AccountDeleted int
	StorageDeleted int
}

type AccountInfo struct {
	CodeSize    int
	Nonce       uint64
	Balance     *big.Int
	CodeHash    common.Hash
	StorageHash common.Hash
}

// New creates a new state from a given trie.
func New(root common.Hash, db Database) (*StateDB, error) {
	tr, err := db.OpenTrie(root)
	if err != nil {
		return nil, err
	}
	return &StateDB{
		db:                   db,
		trie:                 tr,
		originalRoot:         root,
		stateObjects:         make(map[common.Address]*stateObject),
		stateObjectsPending:  make(map[common.Address]struct{}),
		stateObjectsDirty:    make(map[common.Address]struct{}),
		stateObjectsDestruct: make(map[common.Address]struct{}),
		logs:                 make(map[common.Hash][]*types.Log),
		preimages:            make(map[common.Hash][]byte),
		journal:              newJournal(),
		accessList:           newAccessList(),
		transientStorage:     newTransientStorage(),
	}, nil
}

// setError remembers the first non-nil error it is called with.
func (s *StateDB) setError(err error) {
	if s.dbErr == nil {
		s.dbErr = err
	}
}

// Error returns the memorized database failure occurred earlier.
func (s *StateDB) Error() error {
	return s.dbErr
}

// Reset clears out all ephemeral state objects from the state db, but keeps
// the underlying state trie to avoid reloading data for the next operations.
func (s *StateDB) Reset(root common.Hash) error {
	tr, err := s.db.OpenTrie(root)
	if err != nil {
		return err
	}
	s.trie = tr
	s.stateObjects = make(map[common.Address]*stateObject)
	s.stateObjectsPending = make(map[common.Address]struct{})
	s.stateObjectsDirty = make(map[common.Address]struct{})
	s.thash = common.Hash{}
	s.txIndex = 0
	s.logs = make(map[common.Hash][]*types.Log)
	s.logSize = 0
	s.preimages = make(map[common.Hash][]byte)
	s.clearJournalAndRefund()
	s.accessList = newAccessList()
	return nil
}

func (s *StateDB) AddLog(log *types.Log) {
	s.journal.append(addLogChange{txhash: s.thash})

	log.TxHash = s.thash
	log.TxIndex = uint(s.txIndex)
	log.Index = s.logSize
	s.logs[s.thash] = append(s.logs[s.thash], log)
	s.logSize++
}

// GetLogs returns the logs matching the specified transaction hash, and annotates
// them with the given blockNumber and blockHash.
func (s *StateDB) GetLogs(hash common.Hash, blockNumber uint64, blockHash common.Hash) []*types.Log {
	logs := s.logs[hash]
	for _, l := range logs {
		l.BlockNumber = blockNumber
		l.BlockHash = blockHash
	}
	return logs
}

func (s *StateDB) Logs() []*types.Log {
	var logs []*types.Log
	for _, lgs := range s.logs {
		logs = append(logs, lgs...)
	}
	slices.SortFunc(logs, func(a, b *types.Log) int {
		return int(a.Index) - int(b.Index)
	})
	return logs
}

// AddPreimage records a SHA3 preimage seen by the VM.
func (s *StateDB) AddPreimage(hash common.Hash, preimage []byte) {
	if _, ok := s.preimages[hash]; !ok {
		s.journal.append(addPreimageChange{hash: hash})
		pi := make([]byte, len(preimage))
		copy(pi, preimage)
		s.preimages[hash] = pi
	}
}

// Preimages returns a list of SHA3 preimages that have been submitted.
func (s *StateDB) Preimages() map[common.Hash][]byte {
	return s.preimages
}

// AddRefund adds gas to the refund counter
func (s *StateDB) AddRefund(gas uint64) {
	s.journal.append(refundChange{prev: s.refund})
	s.refund += gas
}

// SubRefund removes gas from the refund counter.
// This method will panic if the refund counter goes below zero
func (s *StateDB) SubRefund(gas uint64) {
	s.journal.append(refundChange{prev: s.refund})
	if gas > s.refund {
		panic(fmt.Sprintf("Refund counter below zero (gas: %d > refund: %d)", gas, s.refund))
	}
	s.refund -= gas
}

// Exist reports whether the given account address exists in the state.
// Notably this also returns true for self-destructed accounts.
func (s *StateDB) Exist(addr common.Address) bool {
	return s.getStateObject(addr) != nil
}

// Empty returns whether the state object is either non-existent
// or empty according to the EIP161 specification (balance = nonce = code = 0)
func (s *StateDB) Empty(addr common.Address) bool {
	so := s.getStateObject(addr)
	return so == nil || so.empty()
}

// GetBalance retrieves the balance from the given address or 0 if object not found
func (s *StateDB) GetBalance(addr common.Address) *big.Int {
	stateObject := s.getStateObject(addr)
	if stateObject != nil {
		return stateObject.Balance()
	}
	return common.Big0
}

func (s *StateDB) GetNonce(addr common.Address) uint64 {
	stateObject := s.getStateObject(addr)
	if stateObject != nil {
		return stateObject.Nonce()
	}

	return 0
}

// GetStorageRoot retrieves the storage root from the given address or empty
// if object not found.
func (s *StateDB) GetStorageRoot(addr common.Address) common.Hash {
	stateObject := s.getStateObject(addr)
	if stateObject != nil {
		return stateObject.Root()
	}
	return common.Hash{}
}

// TxIndex returns the current transaction index set by Prepare.
func (s *StateDB) TxIndex() int {
	return s.txIndex
}

func (s *StateDB) GetCode(addr common.Address) []byte {
	stateObject := s.getStateObject(addr)
	if stateObject != nil {
		return stateObject.Code(s.db)
	}
	return nil
}

func (s *StateDB) GetCodeSize(addr common.Address) int {
	stateObject := s.getStateObject(addr)
	if stateObject != nil {
		return stateObject.CodeSize(s.db)
	}
	return 0
}

func (s *StateDB) GetCodeHash(addr common.Address) common.Hash {
	stateObject := s.getStateObject(addr)
	if stateObject == nil {
		return common.Hash{}
	}
	return common.BytesToHash(stateObject.CodeHash())
}

func (s *StateDB) GetAccountInfo(addr common.Address) *AccountInfo {
	result := AccountInfo{}

	stateObject := s.getStateObject(addr)
	if stateObject == nil {
		result.Balance = new(big.Int)
		return &result
	}

	if stateObject.code != nil {
		result.CodeSize = len(stateObject.code)
	} else {
		size, err := s.db.ContractCodeSize(stateObject.addrHash, common.BytesToHash(stateObject.CodeHash()))
		if err != nil {
			s.setError(err)
		}
		result.CodeSize = size
	}
	result.Nonce = stateObject.Nonce()
	result.Balance = stateObject.Balance()
	result.CodeHash = common.BytesToHash(stateObject.CodeHash())
	result.StorageHash = stateObject.Root()

	return &result
}

// GetState retrieves a value from the given account's storage trie.
func (s *StateDB) GetState(addr common.Address, hash common.Hash) common.Hash {
	stateObject := s.getStateObject(addr)
	if stateObject != nil {
		return stateObject.GetState(s.db, hash)
	}
	return common.Hash{}
}

// GetCommittedState retrieves a value from the given account's committed storage trie.
func (s *StateDB) GetCommittedState(addr common.Address, hash common.Hash) common.Hash {
	stateObject := s.getStateObject(addr)
	if stateObject != nil {
		return stateObject.GetCommittedState(s.db, hash)
	}
	return common.Hash{}
}

// Database retrieves the low level database supporting the lower level trie ops.
func (s *StateDB) Database() Database {
	return s.db
}

// StorageTrie returns the storage trie of an account. The return value is a copy
// and is nil for non-existent accounts. An error will be returned if storage trie
// is existent but can't be loaded correctly.
func (s *StateDB) StorageTrie(addr common.Address) (Trie, error) {
	stateObject := s.getStateObject(addr)
	if stateObject == nil {
		return nil, nil
	}
	cpy := stateObject.deepCopy(s)
	if _, err := cpy.updateTrie(s.db); err != nil {
		return nil, err
	}
	return cpy.getTrie(s.db)
}

func (s *StateDB) HasSelfDestructed(addr common.Address) bool {
	stateObject := s.getStateObject(addr)
	if stateObject != nil {
		return stateObject.selfDestructed
	}
	return false
}

/*
 * SETTERS
 */

// AddBalance adds amount to the account associated with addr.
func (s *StateDB) AddBalance(addr common.Address, amount *big.Int, _ tracing.BalanceChangeReason) *big.Int {
	stateObject := s.GetOrNewStateObject(addr)
	if stateObject == nil {
		return new(big.Int)
	}
	return stateObject.AddBalance(amount)
}

// SubBalance subtracts amount from the account associated with addr.
func (s *StateDB) SubBalance(addr common.Address, amount *big.Int, _ tracing.BalanceChangeReason) *big.Int {
	stateObject := s.GetOrNewStateObject(addr)
	if stateObject == nil {
		return new(big.Int)
	}
	prev := stateObject.Balance()
	if amount.Sign() == 0 {
		return new(big.Int).Set(prev)
	}
	return stateObject.SetBalance(new(big.Int).Sub(prev, amount))
}

func (s *StateDB) SetBalance(addr common.Address, amount *big.Int, _ tracing.BalanceChangeReason) {
	stateObject := s.GetOrNewStateObject(addr)
	if stateObject != nil {
		stateObject.SetBalance(amount)
	}
}

func (s *StateDB) SetNonce(addr common.Address, nonce uint64) {
	stateObject := s.GetOrNewStateObject(addr)
	if stateObject != nil {
		stateObject.SetNonce(nonce)
	}
}

func (s *StateDB) SetCode(addr common.Address, code []byte) {
	stateObject := s.GetOrNewStateObject(addr)
	if stateObject != nil {
		stateObject.SetCode(crypto.Keccak256Hash(code), code)
	}
}

func (s *StateDB) SetState(addr common.Address, key, value common.Hash) common.Hash {
	if stateObject := s.GetOrNewStateObject(addr); stateObject != nil {
		return stateObject.SetState(s.db, key, value)
	}
	return common.Hash{}
}

// SetStorage replaces the entire storage for the specified account with given
// storage. This function should only be used for debugging and the mutations
// must be discarded afterwards.
func (s *StateDB) SetStorage(addr common.Address, storage map[common.Hash]common.Hash) {
	// SetStorage needs to wipe the existing storage. We achieve this by marking
	// the account as self-destructed in this block. The effect is that storage
	// lookups will not hit the disk, as it is assumed that the disk data belongs
	// to a previous incarnation of the object.
	//
	// TODO(rjl493456442): This function should only be supported by 'unwritable'
	// state, and all mutations made should be discarded afterward.
	obj := s.getStateObject(addr)
	if obj != nil {
		if _, ok := s.stateObjectsDestruct[addr]; !ok {
			s.stateObjectsDestruct[addr] = struct{}{}
		}
	}
	newObj, _ := s.createObject(addr)
	for k, v := range storage {
		newObj.SetState(s.db, k, v)
	}
	// Inherit the metadata of original object if it was existent
	if obj != nil {
		newObj.SetCode(common.BytesToHash(obj.CodeHash()), obj.code)
		newObj.SetNonce(obj.Nonce())
		newObj.SetBalance(obj.Balance())
	}
}

// SelfDestruct marks the given account as selfdestructed.
// This clears the account balance.
//
// The account's state object is still available until the state is committed,
// getStateObject will return a non-nil account after SelfDestruct.
func (s *StateDB) SelfDestruct(addr common.Address) *big.Int {
	stateObject := s.getStateObject(addr)
	prevBalance := new(big.Int)
	if stateObject == nil {
		return prevBalance
	}
	prevBalance.Set(stateObject.Balance())
	// Regardless of whether it is already destructed or not, we do have to
	// journal the balance-change, if we set it to zero here.
	if prevBalance.Sign() != 0 {
		stateObject.SetBalance(new(big.Int))
	}
	// If it is already marked as self-destructed, we do not need to add it
	// for journalling a second time.
	if !stateObject.selfDestructed {
		s.journal.append(selfDestructChange{
			account:     addr,
			prev:        stateObject.selfDestructed,
			prevbalance: prevBalance,
		})
		stateObject.markSelfdestructed()
	}
	return prevBalance
}

func (s *StateDB) SelfDestruct6780(addr common.Address) (*big.Int, bool) {
	stateObject := s.getStateObject(addr)
	if stateObject == nil {
		return new(big.Int), false
	}
	if stateObject.created {
		return s.SelfDestruct(addr), true
	}
	return new(big.Int).Set(stateObject.Balance()), false
}

// SetTransientState sets transient storage for a given account. It
// adds the change to the journal so that it can be rolled back
// to its previous value if there is a revert.
func (s *StateDB) SetTransientState(addr common.Address, key, value common.Hash) {
	prev := s.GetTransientState(addr, key)
	if prev == value {
		return
	}
	s.journal.append(transientStorageChange{
		account:  addr,
		key:      key,
		prevalue: prev,
	})
	s.setTransientState(addr, key, value)
}

// setTransientState is a lower level setter for transient storage. It
// is called during a revert to prevent modifications to the journal.
func (s *StateDB) setTransientState(addr common.Address, key, value common.Hash) {
	s.transientStorage.Set(addr, key, value)
}

// GetTransientState gets transient storage for a given account.
func (s *StateDB) GetTransientState(addr common.Address, key common.Hash) common.Hash {
	return s.transientStorage.Get(addr, key)
}

//
// Setting, updating & deleting state object methods.
//

// updateStateObject writes the given object to the trie.
func (s *StateDB) updateStateObject(obj *stateObject) {
	// Track the amount of time wasted on updating the account from the trie
	defer func(start time.Time) { s.AccountUpdates += time.Since(start) }(time.Now())

	// Encode the account and update the account trie
	addr := obj.Address()
	if err := s.trie.TryUpdateAccount(addr, &obj.data); err != nil {
		s.setError(fmt.Errorf("updateStateObject (%x) error: %v", addr[:], err))
	}
}

// deleteStateObject removes the given object from the state trie.
func (s *StateDB) deleteStateObject(obj *stateObject) {
	// Track the amount of time wasted on deleting the account from the trie
	defer func(start time.Time) { s.AccountUpdates += time.Since(start) }(time.Now())

	// Delete the account from the trie
	addr := obj.Address()
	if err := s.trie.TryDeleteAccount(addr); err != nil {
		s.setError(fmt.Errorf("deleteStateObject (%x) error: %v", addr[:], err))
	}
}

// DeleteAddress removes the address from the state trie.
func (s *StateDB) DeleteAddress(addr common.Address) {
	stateObject := s.getStateObject(addr)
	if stateObject != nil && !stateObject.deleted {
		stateObject.deleted = true
		s.deleteStateObject(stateObject)
	}
}

// getStateObject retrieves a state object given by the address, returning nil if
// the object is not found or was deleted in this execution context. If you need
// to differentiate between non-existent/just-deleted, use getDeletedStateObject.
func (s *StateDB) getStateObject(addr common.Address) *stateObject {
	if obj := s.getDeletedStateObject(addr); obj != nil && !obj.deleted {
		return obj
	}
	return nil
}

// getDeletedStateObject is similar to getStateObject, but instead of returning
// nil for a deleted state object, it returns the actual object with the deleted
// flag set. This is needed by the state journal to revert to the correct s-
// destructed object instead of wiping all knowledge about the state object.
func (s *StateDB) getDeletedStateObject(addr common.Address) *stateObject {
	// Prefer live objects if any is available
	if obj := s.stateObjects[addr]; obj != nil {
		return obj
	}
	// Load the object from the database
	start := time.Now()
	data, err := s.trie.TryGetAccount(addr)
	s.AccountReads += time.Since(start)
	if err != nil {
		s.setError(fmt.Errorf("getDeleteStateObject (%x) error: %w", addr.Bytes(), err))
		return nil
	}
	if data == nil {
		return nil
	}
	// Insert into the live set
	obj := newObject(s, addr, *data)
	s.setStateObject(obj)
	return obj
}

func (s *StateDB) setStateObject(object *stateObject) {
	s.stateObjects[object.Address()] = object
}

// GetOrNewStateObject retrieves a state object or create a new state object if nil.
func (s *StateDB) GetOrNewStateObject(addr common.Address) *stateObject {
	stateObject := s.getStateObject(addr)
	if stateObject == nil {
		stateObject, _ = s.createObject(addr)
	}
	return stateObject
}

// createObject creates a new state object. If there is an existing account with
// the given address, it is overwritten and returned as the second return value.
func (s *StateDB) createObject(addr common.Address) (newobj, prev *stateObject) {
	prev = s.getDeletedStateObject(addr) // Note, prev might have been deleted, we need that!
	newobj = newObject(s, addr, types.StateAccount{})
	if prev == nil {
		s.journal.append(createObjectChange{account: addr})
	} else {
		_, prevdestruct := s.stateObjectsDestruct[prev.address]
		if !prevdestruct {
			s.stateObjectsDestruct[prev.address] = struct{}{}
		}
		s.journal.append(resetObjectChange{account: addr, prev: prev, prevdestruct: prevdestruct})
	}

	newobj.created = true

	s.setStateObject(newobj)
	if prev != nil && !prev.deleted {
		return newobj, prev
	}
	return newobj, nil
}

// CreateAccount explicitly creates a state object. If a state object with the address
// already exists the balance is carried over to the new account.
//
// CreateAccount is called during the EVM CREATE operation. The situation might arise that
// a contract does the following:
//
//  1. sends funds to sha(account ++ (nonce + 1))
//  2. tx_create(sha(account ++ nonce)) (note that this gets the address of 1)
//
// Carrying over the balance ensures that Ether doesn't disappear.
func (s *StateDB) CreateAccount(addr common.Address) {
	newObj, prev := s.createObject(addr)
	if prev != nil {
		newObj.setBalance(prev.data.Balance)
	}
}

// CreateContract is used whenever a contract is created. This may be preceded
// by CreateAccount, but that is not required if it already existed in the
// state due to funds sent beforehand.
// This operation sets the 'newContract'-flag, which is required in order to
// correctly handle EIP-6780 'delete-in-same-transaction' logic.
func (s *StateDB) CreateContract(addr common.Address) {
	obj := s.getStateObject(addr)
	if obj != nil && !obj.created {
		obj.created = true
		s.journal.createContract(addr)
	}
}

func (s *StateDB) ForEachStorage(addr common.Address, cb func(key, value common.Hash) bool) error {
	so := s.getStateObject(addr)
	if so == nil {
		return nil
	}
	tr, err := so.getTrie(s.db)
	if err != nil {
		return err
	}
	it := trie.NewIterator(tr.NodeIterator(nil))

	for it.Next() {
		key := common.BytesToHash(s.trie.GetKey(it.Key))
		if value, dirty := so.dirtyStorage[key]; dirty {
			if !cb(key, value) {
				return nil
			}
			continue
		}

		if len(it.Value) > 0 {
			_, content, _, err := rlp.Split(it.Value)
			if err != nil {
				return err
			}
			if !cb(key, common.BytesToHash(content)) {
				return nil
			}
		}
	}
	return nil
}

// Copy creates a deep, independent copy of the state.
// Snapshots of the copied state cannot be applied to the copy.
func (s *StateDB) Copy() *StateDB {
	// Copy all the basic fields, initialize the memory ones
	state := &StateDB{
		db:                   s.db,
		trie:                 s.db.CopyTrie(s.trie),
		originalRoot:         s.originalRoot,
		stateObjects:         make(map[common.Address]*stateObject, len(s.journal.dirties)),
		stateObjectsPending:  make(map[common.Address]struct{}, len(s.stateObjectsPending)),
		stateObjectsDirty:    make(map[common.Address]struct{}, len(s.journal.dirties)),
		stateObjectsDestruct: make(map[common.Address]struct{}, len(s.stateObjectsDestruct)),
		refund:               s.refund,
		logs:                 make(map[common.Hash][]*types.Log, len(s.logs)),
		logSize:              s.logSize,
		preimages:            maps.Clone(s.preimages),
		journal:              newJournal(),
	}
	// Copy the dirty states, logs, and preimages
	for addr := range s.journal.dirties {
		// As documented [here](https://github.com/XinFinOrg/XDPoSChain/pull/16485#issuecomment-380438527),
		// and in the Finalise-method, there is a case where an object is in the journal but not
		// in the stateObjects: OOG after touch on ripeMD prior to Byzantium. Thus, we need to check for
		// nil
		if object, exist := s.stateObjects[addr]; exist {
			// Even though the original object is dirty, we are not copying the journal,
			// so we need to make sure that any side-effect the journal would have caused
			// during a commit (or similar op) is already applied to the copy.
			state.stateObjects[addr] = object.deepCopy(state)

			state.stateObjectsDirty[addr] = struct{}{}   // Mark the copy dirty to force internal (code/state) commits
			state.stateObjectsPending[addr] = struct{}{} // Mark the copy pending to force external (account) commits
		}
	}
	// Above, we don't copy the actual journal. This means that if the copy
	// is copied, the loop above will be a no-op, since the copy's journal
	// is empty. Thus, here we iterate over stateObjects, to enable copies
	// of copies.
	for addr := range s.stateObjectsPending {
		if _, exist := state.stateObjects[addr]; !exist {
			state.stateObjects[addr] = s.stateObjects[addr].deepCopy(state)
		}
		state.stateObjectsPending[addr] = struct{}{}
	}
	for addr := range s.stateObjectsDirty {
		if _, exist := state.stateObjects[addr]; !exist {
			state.stateObjects[addr] = s.stateObjects[addr].deepCopy(state)
		}
		state.stateObjectsDirty[addr] = struct{}{}
	}
	// Deep copy the destruction flag.
	state.stateObjectsDestruct = maps.Clone(s.stateObjectsDestruct)
	// Deep copy the logs occurred in the scope of block
	for hash, logs := range s.logs {
		cpy := make([]*types.Log, len(logs))
		for i, l := range logs {
			cpy[i] = new(types.Log)
			*cpy[i] = *l
		}
		state.logs[hash] = cpy
	}
	state.preimages = maps.Clone(s.preimages)
	// Do we need to copy the access list and transient storage?
	// In practice: No. At the start of a transaction, these two lists are empty.
	// In practice, we only ever copy state _between_ transactions/blocks, never
	// in the middle of a transaction. However, it doesn't cost us much to copy
	// empty lists, so we do it anyway to not blow up if we ever decide copy them
	// in the middle of a transaction.
	state.accessList = s.accessList.Copy()
	state.transientStorage = s.transientStorage.Copy()

	return state
}

// Snapshot returns an identifier for the current revision of the state.
func (s *StateDB) Snapshot() int {
	id := s.nextRevisionId
	s.nextRevisionId++
	s.validRevisions = append(s.validRevisions, revision{id, s.journal.length()})
	return id
}

// RevertToSnapshot reverts all state changes made since the given revision.
func (s *StateDB) RevertToSnapshot(revid int) {
	// Find the snapshot in the stack of valid snapshots.
	idx := sort.Search(len(s.validRevisions), func(i int) bool {
		return s.validRevisions[i].id >= revid
	})
	if idx == len(s.validRevisions) || s.validRevisions[idx].id != revid {
		panic(fmt.Errorf("revision id %v cannot be reverted", revid))
	}
	snapshot := s.validRevisions[idx].journalIndex

	// Replay the journal to undo changes and remove invalidated snapshots
	s.journal.revert(s, snapshot)
	s.validRevisions = s.validRevisions[:idx]
}

// GetRefund returns the current value of the refund counter.
func (s *StateDB) GetRefund() uint64 {
	return s.refund
}

// Finalise finalises the state by removing the destructed objects and clears
// the journal as well as the refunds. Finalise, however, will not push any updates
// into the tries just yet. Only IntermediateRoot or Commit will do that.
func (s *StateDB) Finalise(deleteEmptyObjects bool) {
	for addr := range s.journal.dirties {
		obj, exist := s.stateObjects[addr]
		if !exist {
			continue
		}

		if obj.selfDestructed || (deleteEmptyObjects && obj.empty()) {
			obj.deleted = true
			// We need to maintain account deletions explicitly (will remain
			// set indefinitely). Note only the first occurred self-destruct
			// event is tracked.
			if _, ok := s.stateObjectsDestruct[obj.address]; !ok {
				s.stateObjectsDestruct[obj.address] = struct{}{}
			}
		} else {
			obj.finalise()
		}
		obj.created = false
		s.stateObjectsPending[addr] = struct{}{}
		s.stateObjectsDirty[addr] = struct{}{}
	}
	// Invalidate journal because reverting across transactions is not allowed.
	s.clearJournalAndRefund()
}

// IntermediateRoot computes the current root hash of the state trie.
// It is called in between transactions to get the root hash that
// goes into transaction receipts.
func (s *StateDB) IntermediateRoot(deleteEmptyObjects bool) common.Hash {
	// Finalise all the dirty storage states and write them into the tries
	s.Finalise(deleteEmptyObjects)

	// Although naively it makes sense to retrieve the account trie and then do
	// the contract storage and account updates sequentially, that short circuits
	// the account prefetcher. Instead, let's process all the storage updates
	// first, giving the account prefetches just a few more milliseconds of time
	// to pull useful data from disk.
	for addr := range s.stateObjectsPending {
		obj := s.stateObjects[addr]
		if obj.deleted {
			s.deleteStateObject(obj)
			s.AccountDeleted += 1
		} else {
			obj.updateRoot(s.db)
			s.updateStateObject(obj)
			s.AccountUpdated += 1
		}
	}
	if len(s.stateObjectsPending) > 0 {
		s.stateObjectsPending = make(map[common.Address]struct{})
	}
	// Track the amount of time wasted on hashing the account trie
	defer func(start time.Time) { s.AccountHashes += time.Since(start) }(time.Now())

	return s.trie.Hash()
}

// SetTxContext sets the current transaction hash and index which are
// used when the EVM emits new state logs. It should be invoked before
// transaction execution.
func (s *StateDB) SetTxContext(thash common.Hash, ti int) {
	s.thash = thash
	s.txIndex = ti
}

func (s *StateDB) clearJournalAndRefund() {
	s.journal = newJournal()
	s.validRevisions = s.validRevisions[:0]
	s.refund = 0
}

// Commit writes the state to the underlying in-memory trie database.
func (s *StateDB) Commit(deleteEmptyObjects bool) (common.Hash, error) {
	// Finalize any pending changes and merge everything into the tries
	s.IntermediateRoot(deleteEmptyObjects)

	for addr := range s.journal.dirties {
		s.stateObjectsDirty[addr] = struct{}{}
	}
	// Commit objects to the trie, measuring the elapsed time
	var (
		accountTrieNodesUpdated int
		accountTrieNodesDeleted int
		storageTrieNodesUpdated int
		storageTrieNodesDeleted int
		nodes                   = trie.NewMergedNodeSet()
	)
	codeWriter := s.db.DiskDB().NewBatch()
	for addr := range s.stateObjectsDirty {
		if obj := s.stateObjects[addr]; !obj.deleted {
			// Write any contract code associated with the state object
			if obj.code != nil && obj.dirtyCode {
				rawdb.WriteCode(codeWriter, common.BytesToHash(obj.CodeHash()), obj.code)
				obj.dirtyCode = false
			}
			// Write any storage changes in the state object to its storage trie
			set, err := obj.commitTrie(s.db)
			if err != nil {
				return common.Hash{}, err
			}
			// Merge the dirty nodes of storage trie into global set
			if set != nil {
				if err := nodes.Merge(set); err != nil {
					return common.Hash{}, err
				}
				updates, deleted := set.Size()
				storageTrieNodesUpdated += updates
				storageTrieNodesDeleted += deleted
			}
		}
		// If the contract is destructed, the storage is still left in the
		// database as dangling data. Theoretically it's should be wiped from
		// database as well, but in hash-based-scheme it's extremely hard to
		// determine that if the trie nodes are also referenced by other storage,
		// and in path-based-scheme some technical challenges are still unsolved.
		// Although it won't affect the correctness but please fix it TODO(rjl493456442).
	}
	if len(s.stateObjectsDirty) > 0 {
		s.stateObjectsDirty = make(map[common.Address]struct{})
	}
	if codeWriter.ValueSize() > 0 {
		if err := codeWriter.Write(); err != nil {
			log.Crit("Failed to commit dirty codes", "error", err)
		}
	}
	// Write the account trie changes, measuring the amount of wasted time
	start := time.Now()
	root, set := s.trie.Commit(true)
	// Merge the dirty nodes of account trie into global set
	if set != nil {
		if err := nodes.Merge(set); err != nil {
			return common.Hash{}, err
		}
		accountTrieNodesUpdated, accountTrieNodesDeleted = set.Size()
	}
	// Report the commit metrics
	s.AccountCommits += time.Since(start)

	accountUpdatedMeter.Mark(int64(s.AccountUpdated))
	storageUpdatedMeter.Mark(int64(s.StorageUpdated))
	accountDeletedMeter.Mark(int64(s.AccountDeleted))
	storageDeletedMeter.Mark(int64(s.StorageDeleted))
	accountTrieUpdatedMeter.Mark(int64(accountTrieNodesUpdated))
	accountTrieDeletedMeter.Mark(int64(accountTrieNodesDeleted))
	storageTriesUpdatedMeter.Mark(int64(storageTrieNodesUpdated))
	storageTriesDeletedMeter.Mark(int64(storageTrieNodesDeleted))
	s.AccountUpdated, s.AccountDeleted = 0, 0
	s.StorageUpdated, s.StorageDeleted = 0, 0

	if len(s.stateObjectsDestruct) > 0 {
		s.stateObjectsDestruct = make(map[common.Address]struct{})
	}
	if root == (common.Hash{}) {
		root = types.EmptyRootHash
	}
	origin := s.originalRoot
	if origin == (common.Hash{}) {
		origin = types.EmptyRootHash
	}
	if root != origin {
		start := time.Now()
		if err := s.db.TrieDB().Update(nodes); err != nil {
			return common.Hash{}, err
		}
		s.originalRoot = root
		s.TrieDBCommits += time.Since(start)
	}
	return root, nil
}

// Prepare handles the preparatory steps for executing a state transition with.
// This method must be invoked before state transition.
//
// Berlin fork:
// - Add sender to access list (2929)
// - Add destination to access list (2929)
// - Add precompiles to access list (2929)
// - Add the contents of the optional tx access list (2930)
//
// Potential EIPs:
// - Reset access list (Berlin)
// - Add coinbase to access list (EIP-3651)
// - Reset transient storage (EIP-1153)
func (s *StateDB) Prepare(rules params.Rules, sender, coinbase common.Address, dst *common.Address, precompiles []common.Address, list types.AccessList) {
	if rules.IsEIP1559 {
		// Clear out any leftover from previous executions
		al := newAccessList()
		s.accessList = al

		al.AddAddress(sender)
		if dst != nil {
			al.AddAddress(*dst)
			// If it's a create-tx, the destination will be added inside evm.create
		}
		for _, addr := range precompiles {
			al.AddAddress(addr)
		}
		for _, el := range list {
			al.AddAddress(el.Address)
			for _, key := range el.StorageKeys {
				al.AddSlot(el.Address, key)
			}
		}
		// EIP-3651: warm coinbase
		al.AddAddress(coinbase)
	}
	// Reset transient storage at the beginning of transaction execution
	s.transientStorage = newTransientStorage()
}

// AddAddressToAccessList adds the given address to the access list
func (s *StateDB) AddAddressToAccessList(addr common.Address) {
	if s.accessList.AddAddress(addr) {
		s.journal.append(accessListAddAccountChange{addr})
	}
}

// AddSlotToAccessList adds the given (address, slot)-tuple to the access list
func (s *StateDB) AddSlotToAccessList(addr common.Address, slot common.Hash) {
	addrMod, slotMod := s.accessList.AddSlot(addr, slot)
	if addrMod {
		// In practice, this should not happen, since there is no way to enter the
		// scope of 'address' without having the 'address' become already added
		// to the access list (via call-variant, create, etc).
		// Better safe than sorry, though
		s.journal.append(accessListAddAccountChange{addr})
	}
	if slotMod {
		s.journal.append(accessListAddSlotChange{
			address: addr,
			slot:    slot,
		})
	}
}

// AddressInAccessList returns true if the given address is in the access list.
func (s *StateDB) AddressInAccessList(addr common.Address) bool {
	return s.accessList.ContainsAddress(addr)
}

// SlotInAccessList returns true if the given (address, slot)-tuple is in the access list.
func (s *StateDB) SlotInAccessList(addr common.Address, slot common.Hash) (addressPresent bool, slotPresent bool) {
	return s.accessList.Contains(addr, slot)
}

func (s *StateDB) GetOwner(candidate common.Address) common.Address {
	slot := slotValidatorMapping["validatorsState"]
	// validatorsState[_candidate].owner;
	locValidatorsState := GetLocMappingAtKey(candidate.Hash(), slot)
	locCandidateOwner := locValidatorsState.Add(locValidatorsState, new(big.Int).SetUint64(uint64(0)))
	ret := s.GetState(common.MasternodeVotingSMCBinary, common.BigToHash(locCandidateOwner))
	return common.HexToAddress(ret.Hex())
}