class AccountStorageDB(AccountStorageDatabaseAPI): logger = get_extended_debug_logger("eth.db.storage.AccountStorageDB") def __init__(self, db: AtomicDatabaseAPI, storage_root: Hash32, address: Address) -> None: """ Database entries go through several pipes, like so... .. code:: db -> _storage_lookup -> _storage_cache -> _locked_changes -> _journal_storage db is the raw database, we can assume it hits disk when written to. Keys are stored as node hashes and rlp-encoded node values. _storage_lookup is itself a pair of databases: (BatchDB -> HexaryTrie), writes to storage lookup *are* immeditaely applied to a trie, generating the appropriate trie nodes and and root hash (via the HexaryTrie). The writes are *not* persisted to db, until _storage_lookup is explicitly instructed to, via :meth:`StorageLookup.commit_to` _storage_cache is a cache tied to the state root of the trie. It is important that this cache is checked *after* looking for the key in _journal_storage, because the cache is only invalidated after a state root change. Otherwise, you will see data since the last storage root was calculated. _locked_changes is a batch database that includes only those values that are un-revertable in the EVM. Currently, that means changes that completed in a previous transaction. Journaling batches writes at the _journal_storage layer, until persist is called. It manages all the checkpointing and rollbacks that happen during EVM execution. In both _storage_cache and _journal_storage, Keys are set/retrieved as the big_endian encoding of the slot integer, and the rlp-encoded value. """ self._address = address self._storage_lookup = StorageLookup(db, storage_root, address) self._storage_cache = CacheDB(self._storage_lookup) self._locked_changes = BatchDB(self._storage_cache) self._journal_storage = JournalDB(self._locked_changes) def get(self, slot: int, from_journal: bool=True) -> int: key = int_to_big_endian(slot) lookup_db = self._journal_storage if from_journal else self._locked_changes try: encoded_value = lookup_db[key] except MissingStorageTrieNode: raise except KeyError: return 0 if encoded_value == b'': return 0 else: return rlp.decode(encoded_value, sedes=rlp.sedes.big_endian_int) def set(self, slot: int, value: int) -> None: key = int_to_big_endian(slot) if value: self._journal_storage[key] = rlp.encode(value) else: del self._journal_storage[key] def delete(self) -> None: self.logger.debug2( "Deleting all storage in account 0x%s, hashed 0x%s", self._address.hex(), keccak(self._address).hex(), ) self._journal_storage.clear() self._storage_cache.reset_cache() def record(self, checkpoint: JournalDBCheckpoint) -> None: self._journal_storage.record(checkpoint) def discard(self, checkpoint: JournalDBCheckpoint) -> None: self.logger.debug2('discard checkpoint %r', checkpoint) if self._journal_storage.has_checkpoint(checkpoint): self._journal_storage.discard(checkpoint) else: # if the checkpoint comes before this account started tracking, # then simply reset to the beginning self._journal_storage.reset() self._storage_cache.reset_cache() def commit(self, checkpoint: JournalDBCheckpoint) -> None: if self._journal_storage.has_checkpoint(checkpoint): self._journal_storage.commit(checkpoint) else: # if the checkpoint comes before this account started tracking, # then flatten all changes, without persisting self._journal_storage.flatten() def lock_changes(self) -> None: self._journal_storage.persist() def make_storage_root(self) -> None: self.lock_changes() self._locked_changes.commit(apply_deletes=True) def _validate_flushed(self) -> None: """ Will raise an exception if there are some changes made since the last persist. """ journal_diff = self._journal_storage.diff() if len(journal_diff) > 0: raise ValidationError( f"StorageDB had a dirty journal when it needed to be clean: {journal_diff!r}" ) @property def has_changed_root(self) -> bool: return self._storage_lookup.has_changed_root def get_changed_root(self) -> Hash32: return self._storage_lookup.get_changed_root() def persist(self, db: DatabaseAPI) -> None: self._validate_flushed() if self._storage_lookup.has_changed_root: self._storage_lookup.commit_to(db)
class AccountStorageDB(AccountStorageDatabaseAPI): logger = get_extended_debug_logger("eth.db.storage.AccountStorageDB") def __init__(self, db: AtomicDatabaseAPI, storage_root: Hash32, address: Address) -> None: """ Database entries go through several pipes, like so... .. code:: db -> _storage_lookup -> _storage_cache -> _locked_changes -> _journal_storage db is the raw database, we can assume it hits disk when written to. Keys are stored as node hashes and rlp-encoded node values. _storage_lookup is itself a pair of databases: (BatchDB -> HexaryTrie), writes to storage lookup *are* immeditaely applied to a trie, generating the appropriate trie nodes and and root hash (via the HexaryTrie). The writes are *not* persisted to db, until _storage_lookup is explicitly instructed to, via :meth:`StorageLookup.commit_to` _storage_cache is a cache tied to the state root of the trie. It is important that this cache is checked *after* looking for the key in _journal_storage, because the cache is only invalidated after a state root change. Otherwise, you will see data since the last storage root was calculated. _locked_changes is a batch database that includes only those values that are un-revertable in the EVM. Currently, that means changes that completed in a previous transaction. Journaling batches writes at the _journal_storage layer, until persist is called. It manages all the checkpointing and rollbacks that happen during EVM execution. In both _storage_cache and _journal_storage, Keys are set/retrieved as the big_endian encoding of the slot integer, and the rlp-encoded value. """ self._address = address self._storage_lookup = StorageLookup(db, storage_root, address) self._storage_cache = CacheDB(self._storage_lookup) self._locked_changes = JournalDB(self._storage_cache) self._journal_storage = JournalDB(self._locked_changes) # Track how many times we have cleared the storage. This is journaled # in lockstep with other storage changes. That way, we can detect if a revert # causes use to revert past the previous storage deletion. The clear count is used # as an index to find the base trie from before the revert. self._clear_count = JournalDB( MemoryDB({CLEAR_COUNT_KEY_NAME: to_bytes(0)})) def get(self, slot: int, from_journal: bool = True) -> int: key = int_to_big_endian(slot) lookup_db = self._journal_storage if from_journal else self._locked_changes try: encoded_value = lookup_db[key] except MissingStorageTrieNode: raise except KeyError: return 0 if encoded_value == b'': return 0 else: return rlp.decode(encoded_value, sedes=rlp.sedes.big_endian_int) def set(self, slot: int, value: int) -> None: key = int_to_big_endian(slot) if value: self._journal_storage[key] = rlp.encode(value) else: try: current_val = self._journal_storage[key] except KeyError: # deleting an empty key has no effect return else: if current_val != b'': # only try to delete the value if it's present del self._journal_storage[key] def delete(self) -> None: self.logger.debug2( "Deleting all storage in account 0x%s", self._address.hex(), ) self._journal_storage.clear() self._storage_cache.reset_cache() # Empty out the storage lookup trie (keeping history, in case of a revert) new_clear_count = self._storage_lookup.new_trie() # Look up the previous count of how many times the account has been deleted. # This can happen multiple times in one block, via CREATE2. old_clear_count = to_int(self._clear_count[CLEAR_COUNT_KEY_NAME]) # Gut check that we have incremented correctly if new_clear_count != old_clear_count + 1: raise ValidationError( f"Must increase clear count by one on each delete. Instead, went from" f" {old_clear_count} -> {new_clear_count} in account 0x{self._address.hex()}" ) # Save the new count, ie~ the index used for a future revert. self._clear_count[CLEAR_COUNT_KEY_NAME] = to_bytes(new_clear_count) def record(self, checkpoint: JournalDBCheckpoint) -> None: self._journal_storage.record(checkpoint) self._clear_count.record(checkpoint) def discard(self, checkpoint: JournalDBCheckpoint) -> None: self.logger.debug2('discard checkpoint %r', checkpoint) latest_clear_count = to_int(self._clear_count[CLEAR_COUNT_KEY_NAME]) if self._journal_storage.has_checkpoint(checkpoint): self._journal_storage.discard(checkpoint) self._clear_count.discard(checkpoint) else: # if the checkpoint comes before this account started tracking, # then simply reset to the beginning self._journal_storage.reset() self._clear_count.reset() self._storage_cache.reset_cache() reverted_clear_count = to_int(self._clear_count[CLEAR_COUNT_KEY_NAME]) if reverted_clear_count == latest_clear_count - 1: # This revert rewinds past a trie deletion, so roll back to the trie at # that point. We use the clear count as an index to get back to the # old base trie. self._storage_lookup.rollback_trie(reverted_clear_count) elif reverted_clear_count == latest_clear_count: # No change in the base trie, take no action pass else: # Although CREATE2 permits multiple creates and deletes in a single block, # you can still only revert across a single delete. That's because delete # is only triggered at the end of the transaction. raise ValidationError( f"This revert has changed the clear count in an invalid way, from" f" {latest_clear_count} to {reverted_clear_count}, in 0x{self._address.hex()}" ) def commit(self, checkpoint: JournalDBCheckpoint) -> None: if self._journal_storage.has_checkpoint(checkpoint): self._journal_storage.commit(checkpoint) self._clear_count.commit(checkpoint) else: # if the checkpoint comes before this account started tracking, # then flatten all changes, without persisting self._journal_storage.flatten() self._clear_count.flatten() def lock_changes(self) -> None: if self._journal_storage.has_clear(): self._locked_changes.clear() self._journal_storage.persist() def make_storage_root(self) -> None: self.lock_changes() self._locked_changes.persist() def _validate_flushed(self) -> None: """ Will raise an exception if there are some changes made since the last persist. """ journal_diff = self._journal_storage.diff() if len(journal_diff) > 0: raise ValidationError( f"StorageDB had a dirty journal when it needed to be clean: {journal_diff!r}" ) @property def has_changed_root(self) -> bool: return self._storage_lookup.has_changed_root def get_changed_root(self) -> Hash32: return self._storage_lookup.get_changed_root() def persist(self, db: DatabaseAPI) -> None: self._validate_flushed() if self._storage_lookup.has_changed_root: self._storage_lookup.commit_to(db)
class JournalComparison(RuleBasedStateMachine): """ Compare an older version of JournalDB against a newer, optimized one. """ def __init__(self): super().__init__() self.slow_wrapped = {} self.slow_journal = SlowJournalDB(self.slow_wrapped) self.fast_wrapped = {} self.fast_journal = JournalDB(self.fast_wrapped) keys = Bundle('keys') values = Bundle('values') checkpoints = Bundle('checkpoints') @rule(target=keys, k=st.binary()) def add_key(self, k): return k @rule(target=values, v=st.binary()) def add_value(self, v): return v @rule(target=checkpoints) def record(self): slow_checkpoint = self.slow_journal.record() fast_checkpoint = self.fast_journal.record() assert self.slow_journal.diff() == self.fast_journal.diff() return slow_checkpoint, fast_checkpoint @rule(k=keys, v=values) def set(self, k, v): self.slow_journal[k] = v self.fast_journal[k] = v assert self.slow_journal.diff() == self.fast_journal.diff() @rule(k=keys) def delete(self, k): if k not in self.slow_journal: assert k not in self.fast_journal return else: del self.slow_journal[k] del self.fast_journal[k] assert self.slow_journal.diff() == self.fast_journal.diff() @rule(c=checkpoints) def commit(self, c): slow_checkpoint, fast_checkpoint = c if not self.slow_journal.has_changeset(slow_checkpoint): assert not self.fast_journal.has_checkpoint(fast_checkpoint) return else: self.slow_journal.commit(slow_checkpoint) self.fast_journal.commit(fast_checkpoint) assert self.slow_journal.diff() == self.fast_journal.diff() @rule(c=checkpoints) def discard(self, c): slow_checkpoint, fast_checkpoint = c if not self.slow_journal.has_changeset(slow_checkpoint): assert not self.fast_journal.has_checkpoint(fast_checkpoint) else: self.slow_journal.discard(slow_checkpoint) self.fast_journal.discard(fast_checkpoint) assert self.slow_journal.diff() == self.fast_journal.diff() @rule() def flatten(self): self.slow_journal.flatten() self.fast_journal.flatten() assert self.slow_journal.diff() == self.fast_journal.diff() @rule() def persist(self): self.slow_journal.persist() self.fast_journal.persist() assert self.slow_wrapped == self.fast_wrapped