// Copyright 2018 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 rawdb
import (
"bytes"
"errors"
"fmt"
"os"
"sync/atomic"
"time"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/ethdb"
"github.com/ethereum/go-ethereum/ethdb/leveldb"
"github.com/ethereum/go-ethereum/ethdb/memorydb"
"github.com/ethereum/go-ethereum/log"
"github.com/olekukonko/tablewriter"
)
// freezerdb is a database wrapper that enabled freezer data retrievals.
type freezerdb struct {
ethdb.KeyValueStore
ethdb.AncientStore
}
// Close implements io.Closer, closing both the fast key-value store as well as
// the slow ancient tables.
func (frdb *freezerdb) Close() error {
var errs []error
if err := frdb.AncientStore.Close(); err != nil {
errs = append(errs, err)
}
if err := frdb.KeyValueStore.Close(); err != nil {
errs = append(errs, err)
}
if len(errs) != 0 {
return fmt.Errorf("%v", errs)
}
return nil
}
// Freeze is a helper method used for external testing to trigger and block until
// a freeze cycle completes, without having to sleep for a minute to trigger the
// automatic background run.
func (frdb *freezerdb) Freeze(threshold uint64) {
// Set the freezer threshold to a temporary value
defer func(old uint64) {
atomic.StoreUint64(&frdb.AncientStore.(*freezer).threshold, old)
}(atomic.LoadUint64(&frdb.AncientStore.(*freezer).threshold))
atomic.StoreUint64(&frdb.AncientStore.(*freezer).threshold, threshold)
// Trigger a freeze cycle and block until it's done
trigger := make(chan struct{}, 1)
frdb.AncientStore.(*freezer).trigger <- trigger
<-trigger
}
// nofreezedb is a database wrapper that disables freezer data retrievals.
type nofreezedb struct {
ethdb.KeyValueStore
}
// HasAncient returns an error as we don't have a backing chain freezer.
func (db *nofreezedb) HasAncient(kind string, number uint64) (bool, error) {
return false, errNotSupported
}
// Ancient returns an error as we don't have a backing chain freezer.
func (db *nofreezedb) Ancient(kind string, number uint64) ([]byte, error) {
return nil, errNotSupported
}
// Ancients returns an error as we don't have a backing chain freezer.
func (db *nofreezedb) Ancients() (uint64, error) {
return 0, errNotSupported
}
// AncientSize returns an error as we don't have a backing chain freezer.
func (db *nofreezedb) AncientSize(kind string) (uint64, error) {
return 0, errNotSupported
}
// AppendAncient returns an error as we don't have a backing chain freezer.
func (db *nofreezedb) AppendAncient(number uint64, hash, header, body, receipts, td []byte) error {
return errNotSupported
}
// TruncateAncients returns an error as we don't have a backing chain freezer.
func (db *nofreezedb) TruncateAncients(items uint64) error {
return errNotSupported
}
// Sync returns an error as we don't have a backing chain freezer.
func (db *nofreezedb) Sync() error {
return errNotSupported
}
// NewDatabase creates a high level database on top of a given key-value data
// store without a freezer moving immutable chain segments into cold storage.
func NewDatabase(db ethdb.KeyValueStore) ethdb.Database {
return &nofreezedb{
KeyValueStore: db,
}
}
// NewDatabaseWithFreezer creates a high level database on top of a given key-
// value data store with a freezer moving immutable chain segments into cold
// storage.
func NewDatabaseWithFreezer(db ethdb.KeyValueStore, freezer string, namespace string) (ethdb.Database, error) {
// Create the idle freezer instance
frdb, err := newFreezer(freezer, namespace)
if err != nil {
return nil, err
}
// Since the freezer can be stored separately from the user's key-value database,
// there's a fairly high probability that the user requests invalid combinations
// of the freezer and database. Ensure that we don't shoot ourselves in the foot
// by serving up conflicting data, leading to both datastores getting corrupted.
//
// - If both the freezer and key-value store is empty (no genesis), we just
// initialized a new empty freezer, so everything's fine.
// - If the key-value store is empty, but the freezer is not, we need to make
// sure the user's genesis matches the freezer. That will be checked in the
// blockchain, since we don't have the genesis block here (nor should we at
// this point care, the key-value/freezer combo is valid).
// - If neither the key-value store nor the freezer is empty, cross validate
// the genesis hashes to make sure they are compatible. If they are, also
// ensure that there's no gap between the freezer and sunsequently leveldb.
// - If the key-value store is not empty, but the freezer is we might just be
// upgrading to the freezer release, or we might have had a small chain and
// not frozen anything yet. Ensure that no blocks are missing yet from the
// key-value store, since that would mean we already had an old freezer.
// If the genesis hash is empty, we have a new key-value store, so nothing to
// validate in this method. If, however, the genesis hash is not nil, compare
// it to the freezer content.
if kvgenesis, _ := db.Get(headerHashKey(0)); len(kvgenesis) > 0 {
if frozen, _ := frdb.Ancients(); frozen > 0 {
// If the freezer already contains something, ensure that the genesis blocks
// match, otherwise we might mix up freezers across chains and destroy both
// the freezer and the key-value store.
frgenesis, err := frdb.Ancient(freezerHashTable, 0)
if err != nil {
return nil, fmt.Errorf("failed to retrieve genesis from ancient %v", err)
} else if !bytes.Equal(kvgenesis, frgenesis) {
return nil, fmt.Errorf("genesis mismatch: %#x (leveldb) != %#x (ancients)", kvgenesis, frgenesis)
}
// Key-value store and freezer belong to the same network. Ensure that they
// are contiguous, otherwise we might end up with a non-functional freezer.
if kvhash, _ := db.Get(headerHashKey(frozen)); len(kvhash) == 0 {
// Subsequent header after the freezer limit is missing from the database.
// Reject startup is the database has a more recent head.
if *ReadHeaderNumber(db, ReadHeadHeaderHash(db)) > frozen-1 {
return nil, fmt.Errorf("gap (#%d) in the chain between ancients and leveldb", frozen)
}
// Database contains only older data than the freezer, this happens if the
// state was wiped and reinited from an existing freezer.
}
// Otherwise, key-value store continues where the freezer left off, all is fine.
// We might have duplicate blocks (crash after freezer write but before key-value
// store deletion, but that's fine).
} else {
// If the freezer is empty, ensure nothing was moved yet from the key-value
// store, otherwise we'll end up missing data. We check block #1 to decide
// if we froze anything previously or not, but do take care of databases with
// only the genesis block.
if ReadHeadHeaderHash(db) != common.BytesToHash(kvgenesis) {
// Key-value store contains more data than the genesis bloc