ipld-eth-statedb/direct_by_leaf/statedb.go

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package state
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import (
"fmt"
"sort"
"time"
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"github.com/ethereum/go-ethereum/common"
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"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/core/vm"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/metrics"
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"github.com/ethereum/go-ethereum/params"
"github.com/holiman/uint256"
)
const (
// storageDeleteLimit denotes the highest permissible memory allocation
// employed for contract storage deletion.
storageDeleteLimit = 512 * 1024 * 1024
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)
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/*
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The portions of the EVM we want to leverage only use the following methods
(The rest can be left with panics for now):
* Exist
* CreateAccount
* GetCodeHash
* AddAddressToAccessList
* {Get,Set}Nonce
* {Get,Set,Add,Sub}Balance
* {Get,Set}Code
* {Get,Set}State
* {Get,Set}TransientState
* Snapshot
* RevertToSnapshot
*/
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var _ vm.StateDB = &StateDB{}
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
//
// Once the state is committed, tries cached in stateDB (including account
// trie, storage tries) will no longer be functional. A new state instance
// must be created with new root and updated database for accessing post-
// commit states.
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type StateDB struct {
db Database
hasher crypto.KeccakState
// originBlockHash is the blockhash for the state we are working on top of
originBlockHash common.Hash
// originalRoot is the pre-state root, before any changes were made.
// It will be updated when the Commit is called.
originalRoot common.Hash
// These maps hold the state changes (including the corresponding
// original value) that occurred in this **block**.
accounts map[common.Hash][]byte // The mutated accounts in 'slim RLP' encoding
storages map[common.Hash]map[common.Hash][]byte // The mutated slots in prefix-zero trimmed rlp format
accountsOrigin map[common.Address][]byte // The original value of mutated accounts in 'slim RLP' encoding
storagesOrigin map[common.Address]map[common.Hash][]byte // The original value of mutated slots in prefix-zero trimmed rlp format
// 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]*types.StateAccount // State objects destructed in the block along with its previous value
// 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.
dbErr error
// The refund counter, also used by state transitioning.
refund uint64
// The tx context and all occurred logs in the scope of transaction.
thash common.Hash
txIndex int
logs map[common.Hash][]*types.Log
logSize uint
// Preimages occurred seen by VM in the scope of block.
preimages map[common.Hash][]byte
// Per-transaction access list
accessList *accessList
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// 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
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AccountReads time.Duration
StorageReads time.Duration
}
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// New creates a new StateDB on the state for the provided blockHash
func New(blockHash common.Hash, db Database) (*StateDB, error) {
sdb := &StateDB{
db: db,
originBlockHash: blockHash,
stateObjects: make(map[common.Address]*stateObject),
stateObjectsPending: make(map[common.Address]struct{}),
stateObjectsDirty: make(map[common.Address]struct{}),
stateObjectsDestruct: make(map[common.Address]*types.StateAccount),
logs: make(map[common.Hash][]*types.Log),
preimages: make(map[common.Hash][]byte),
journal: newJournal(),
accessList: newAccessList(),
transientStorage: newTransientStorage(),
hasher: crypto.NewKeccakState(),
}
return sdb, 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
}
}
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++
}
// 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
}
}
// AddRefund adds gas to the refund counter
func (s *StateDB) AddRefund(gas uint64) {
s.journal.append(refundChange{prev: s.refund})
s.refund += gas
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}
// 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
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}
// 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
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}
// 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()
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}
// GetBalance retrieves the balance from the given address or 0 if object not found
func (s *StateDB) GetBalance(addr common.Address) *uint256.Int {
stateObject := s.getStateObject(addr)
if stateObject != nil {
return stateObject.Balance()
}
return common.U2560
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}
// GetNonce retrieves the nonce from the given address or 0 if object not found
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()
}
return nil
}
func (s *StateDB) GetCodeSize(addr common.Address) int {
stateObject := s.getStateObject(addr)
if stateObject != nil {
return stateObject.CodeSize()
}
return 0
}
func (s *StateDB) GetCodeHash(addr common.Address) common.Hash {
stateObject := s.getStateObject(addr)
if stateObject != nil {
return common.BytesToHash(stateObject.CodeHash())
}
return common.Hash{}
}
// 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(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(hash)
}
return common.Hash{}
}
// Database retrieves the low level database supporting the lower level trie ops.
func (s *StateDB) Database() Database {
return s.db
}
func (s *StateDB) HasSelfDestructed(addr common.Address) bool {
stateObject := s.getStateObject(addr)
if stateObject != nil {
return stateObject.selfDestructed
}
return false
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}
/*
* SETTERS
*/
// AddBalance adds amount to the account associated with addr.
func (s *StateDB) AddBalance(addr common.Address, amount *uint256.Int) {
stateObject := s.getOrNewStateObject(addr)
if stateObject != nil {
stateObject.AddBalance(amount)
}
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}
// SubBalance subtracts amount from the account associated with addr.
func (s *StateDB) SubBalance(addr common.Address, amount *uint256.Int) {
stateObject := s.getOrNewStateObject(addr)
if stateObject != nil {
stateObject.SubBalance(amount)
}
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}
func (s *StateDB) SetBalance(addr common.Address, amount *uint256.Int) {
stateObject := s.getOrNewStateObject(addr)
if stateObject != nil {
stateObject.SetBalance(amount)
}
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}
func (s *StateDB) SetNonce(addr common.Address, nonce uint64) {
stateObject := s.getOrNewStateObject(addr)
if stateObject != nil {
stateObject.SetNonce(nonce)
}
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}
func (s *StateDB) SetCode(addr common.Address, code []byte) {
stateObject := s.getOrNewStateObject(addr)
if stateObject != nil {
stateObject.SetCode(crypto.Keccak256Hash(code), code)
}
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}
func (s *StateDB) SetState(addr common.Address, key, value common.Hash) {
stateObject := s.getOrNewStateObject(addr)
if stateObject != nil {
stateObject.SetState(key, value)
}
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}
// 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 existing storage. We achieve this by pretending
// that the account self-destructed earlier in this block, by flagging
// it in stateObjectsDestruct. The effect of doing so is that storage lookups
// will not hit disk, since it is assumed that the disk-data is belonging
// to a previous incarnation of the object.
//
// TODO(rjl493456442) this function should only be supported by 'unwritable'
// state and all mutations made should all be discarded afterwards.
if _, ok := s.stateObjectsDestruct[addr]; !ok {
s.stateObjectsDestruct[addr] = nil
}
stateObject := s.getOrNewStateObject(addr)
for k, v := range storage {
stateObject.SetState(k, v)
}
}
// 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) {
stateObject := s.getStateObject(addr)
if stateObject == nil {
return
}
s.journal.append(selfDestructChange{
account: &addr,
prev: stateObject.selfDestructed,
prevbalance: new(uint256.Int).Set(stateObject.Balance()),
})
stateObject.markSelfdestructed()
stateObject.data.Balance = new(uint256.Int)
}
func (s *StateDB) Selfdestruct6780(addr common.Address) {
stateObject := s.getStateObject(addr)
if stateObject == nil {
return
}
if stateObject.created {
s.SelfDestruct(addr)
}
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}
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// 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.
//
// 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
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}
// 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.
// TODO:
func (s *StateDB) getDeletedStateObject(addr common.Address) *stateObject {
// Prefer live objects if any is available
if obj := s.stateObjects[addr]; obj != nil {
return obj
}
// If no live objects are available, load from the database
// TODO: REPLACE TRIE ACCESS HERE
// can add a fallback option to use ipfsethdb to do the trie access if direct access fails
start := time.Now()
addrHash := crypto.Keccak256Hash(addr.Bytes())
data, err := s.db.StateAccount(addrHash, s.originBlockHash)
if metrics.EnabledExpensive {
s.AccountReads += time.Since(start)
}
if err != nil {
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s.setError(fmt.Errorf("getDeletedStateObject (%x) error: %w", addr.Bytes(), err))
return nil
}
if data == nil {
return nil
}
// Insert into the live set
obj := newObject(s, addr, data, s.originBlockHash)
s.setStateObject(obj)
return obj
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}
func (s *StateDB) setStateObject(object *stateObject) {
s.stateObjects[object.Address()] = object
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}
// 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
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}
// 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, nil, s.originBlockHash)
if prev == nil {
s.journal.append(createObjectChange{account: &addr})
} else {
// The original account should be marked as destructed and all cached
// account and storage data should be cleared as well. Note, it must
// be done here, otherwise the destruction event of "original account"
// will be lost.
_, prevdestruct := s.stateObjectsDestruct[prev.address]
if !prevdestruct {
s.stateObjectsDestruct[prev.address] = prev.origin
}
// There may be some cached account/storage data already since IntermediateRoot
// will be called for each transaction before byzantium fork which will always
// cache the latest account/storage data.
prevAccount, ok := s.accountsOrigin[prev.address]
s.journal.append(resetObjectChange{
account: &addr,
prev: prev,
prevdestruct: prevdestruct,
prevAccount: s.accounts[prev.addrHash],
prevStorage: s.storages[prev.addrHash],
prevAccountOriginExist: ok,
prevAccountOrigin: prevAccount,
prevStorageOrigin: s.storagesOrigin[prev.address],
})
delete(s.accounts, prev.addrHash)
delete(s.storages, prev.addrHash)
delete(s.accountsOrigin, prev.address)
delete(s.storagesOrigin, prev.address)
}
s.setStateObject(newobj)
if prev != nil && !prev.deleted {
return newobj, prev
}
return newobj, nil
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}
// 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:
//
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// 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)
}
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}
// 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
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}
// 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))
}
snp := s.validRevisions[idx].journalIndex
// Replay the journal to undo changes and remove invalidated snapshots
s.journal.revert(s, snp)
s.validRevisions = s.validRevisions[:idx]
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}
// GetRefund returns the current value of the refund counter.
func (s *StateDB) GetRefund() uint64 {
return s.refund
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}
// 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) {
addressesToPrefetch := make([][]byte, 0, len(s.journal.dirties))
for addr := range s.journal.dirties {
obj, exist := s.stateObjects[addr]
if !exist {
// ripeMD is 'touched' at block 1714175, in tx 0x1237f737031e40bcde4a8b7e717b2d15e3ecadfe49bb1bbc71ee9deb09c6fcf2
// That tx goes out of gas, and although the notion of 'touched' does not exist there, the
// touch-event will still be recorded in the journal. Since ripeMD is a special snowflake,
// it will persist in the journal even though the journal is reverted. In this special circumstance,
// it may exist in `s.journal.dirties` but not in `s.stateObjects`.
// Thus, we can safely ignore it here
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] = obj.origin
}
// Note, we can't do this only at the end of a block because multiple
// transactions within the same block might self destruct and then
// resurrect an account; but the snapshotter needs both events.
delete(s.accounts, obj.addrHash) // Clear out any previously updated account data (may be recreated via a resurrect)
delete(s.storages, obj.addrHash) // Clear out any previously updated storage data (may be recreated via a resurrect)
delete(s.accountsOrigin, obj.address) // Clear out any previously updated account data (may be recreated via a resurrect)
delete(s.storagesOrigin, obj.address) // Clear out any previously updated storage data (may be recreated via a resurrect)
} else {
obj.finalise(true) // Prefetch slots in the background
}
obj.created = false
s.stateObjectsPending[addr] = struct{}{}
s.stateObjectsDirty[addr] = struct{}{}
// At this point, also ship the address off to the precacher. The precacher
// will start loading tries, and when the change is eventually committed,
// the commit-phase will be a lot faster
addressesToPrefetch = append(addressesToPrefetch, common.CopyBytes(addr[:])) // Copy needed for closure
}
// Invalidate journal because reverting across transactions is not allowed.
s.clearJournalAndRefund()
}
// 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() {
if len(s.journal.entries) > 0 {
s.journal = newJournal()
s.refund = 0
}
s.validRevisions = s.validRevisions[:0] // Snapshots can be created without journal entries
}
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// Prepare handles the preparatory steps for executing a state transition with.
// This method must be invoked before state transition.
//
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// 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)
//
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// 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.IsBerlin {
// 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)
}
}
if rules.IsShanghai { // EIP-3651: warm coinbase
al.AddAddress(coinbase)
}
}
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// Reset transient storage at the beginning of transaction execution
s.transientStorage = newTransientStorage()
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}
// 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})
}
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}
// 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,
})
}
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}
// 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)
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}
// 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)
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}
// 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,
originalRoot: s.originalRoot,
accounts: make(map[common.Hash][]byte),
storages: make(map[common.Hash]map[common.Hash][]byte),
accountsOrigin: make(map[common.Address][]byte),
storagesOrigin: make(map[common.Address]map[common.Hash][]byte),
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]*types.StateAccount, len(s.stateObjectsDestruct)),
refund: s.refund,
logs: make(map[common.Hash][]*types.Log, len(s.logs)),
logSize: s.logSize,
preimages: make(map[common.Hash][]byte, len(s.preimages)),
journal: newJournal(),
hasher: crypto.NewKeccakState(),
}
// Copy the dirty states, logs, and preimages
for addr := range s.journal.dirties {
// As documented [here](https://github.com/ethereum/go-ethereum/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 markers.
for addr, value := range s.stateObjectsDestruct {
state.stateObjectsDestruct[addr] = value
}
// Deep copy the state changes made in the scope of block
// along with their original values.
state.accounts = copySet(s.accounts)
state.storages = copy2DSet(s.storages)
state.accountsOrigin = copySet(state.accountsOrigin)
state.storagesOrigin = copy2DSet(state.storagesOrigin)
// 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
}
// Deep copy the preimages occurred in the scope of block
for hash, preimage := range s.preimages {
state.preimages[hash] = preimage
}
// 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
}
// copySet returns a deep-copied set.
func copySet[k comparable](set map[k][]byte) map[k][]byte {
copied := make(map[k][]byte, len(set))
for key, val := range set {
copied[key] = common.CopyBytes(val)
}
return copied
}
// copy2DSet returns a two-dimensional deep-copied set.
func copy2DSet[k comparable](set map[k]map[common.Hash][]byte) map[k]map[common.Hash][]byte {
copied := make(map[k]map[common.Hash][]byte, len(set))
for addr, subset := range set {
copied[addr] = make(map[common.Hash][]byte, len(subset))
for key, val := range subset {
copied[addr][key] = common.CopyBytes(val)
}
}
return copied
}