plugeth/core/database_util.go

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// Copyright 2015 The go-ethereum Authors
// This file is part of the go-ethereum library.
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//
// The go-ethereum library is free software: you can redistribute it and/or modify
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// 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,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// 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/>.
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package core
import (
"bytes"
"encoding/binary"
"encoding/json"
"errors"
"fmt"
"math/big"
"sync"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/ethdb"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/metrics"
"github.com/ethereum/go-ethereum/params"
"github.com/ethereum/go-ethereum/rlp"
)
var (
headHeaderKey = []byte("LastHeader")
headBlockKey = []byte("LastBlock")
headFastKey = []byte("LastFast")
headerPrefix = []byte("h") // headerPrefix + num (uint64 big endian) + hash -> header
tdSuffix = []byte("t") // headerPrefix + num (uint64 big endian) + hash + tdSuffix -> td
numSuffix = []byte("n") // headerPrefix + num (uint64 big endian) + numSuffix -> hash
blockHashPrefix = []byte("H") // blockHashPrefix + hash -> num (uint64 big endian)
bodyPrefix = []byte("b") // bodyPrefix + num (uint64 big endian) + hash -> block body
blockReceiptsPrefix = []byte("r") // blockReceiptsPrefix + num (uint64 big endian) + hash -> block receipts
preimagePrefix = "secure-key-" // preimagePrefix + hash -> preimage
txMetaSuffix = []byte{0x01}
receiptsPrefix = []byte("receipts-")
mipmapPre = []byte("mipmap-log-bloom-")
MIPMapLevels = []uint64{1000000, 500000, 100000, 50000, 1000}
configPrefix = []byte("ethereum-config-") // config prefix for the db
// used by old (non-sequential keys) db, now only used for conversion
oldBlockPrefix = []byte("block-")
oldHeaderSuffix = []byte("-header")
oldTdSuffix = []byte("-td") // headerPrefix + num (uint64 big endian) + hash + tdSuffix -> td
oldBodySuffix = []byte("-body")
oldBlockNumPrefix = []byte("block-num-")
oldBlockReceiptsPrefix = []byte("receipts-block-")
oldBlockHashPrefix = []byte("block-hash-") // [deprecated by the header/block split, remove eventually]
ChainConfigNotFoundErr = errors.New("ChainConfig not found") // general config not found error
mipmapBloomMu sync.Mutex // protect against race condition when updating mipmap blooms
preimageCounter = metrics.NewCounter("db/preimage/total")
preimageHitCounter = metrics.NewCounter("db/preimage/hits")
)
// encodeBlockNumber encodes a block number as big endian uint64
func encodeBlockNumber(number uint64) []byte {
enc := make([]byte, 8)
binary.BigEndian.PutUint64(enc, number)
return enc
}
// GetCanonicalHash retrieves a hash assigned to a canonical block number.
func GetCanonicalHash(db ethdb.Database, number uint64) common.Hash {
data, _ := db.Get(append(append(headerPrefix, encodeBlockNumber(number)...), numSuffix...))
if len(data) == 0 {
data, _ = db.Get(append(oldBlockNumPrefix, big.NewInt(int64(number)).Bytes()...))
if len(data) == 0 {
return common.Hash{}
}
}
return common.BytesToHash(data)
}
// missingNumber is returned by GetBlockNumber if no header with the
// given block hash has been stored in the database
const missingNumber = uint64(0xffffffffffffffff)
// GetBlockNumber returns the block number assigned to a block hash
// if the corresponding header is present in the database
func GetBlockNumber(db ethdb.Database, hash common.Hash) uint64 {
data, _ := db.Get(append(blockHashPrefix, hash.Bytes()...))
if len(data) != 8 {
data, _ := db.Get(append(append(oldBlockPrefix, hash.Bytes()...), oldHeaderSuffix...))
if len(data) == 0 {
return missingNumber
}
header := new(types.Header)
if err := rlp.Decode(bytes.NewReader(data), header); err != nil {
log.Crit("Failed to decode block header", "err", err)
}
return header.Number.Uint64()
}
return binary.BigEndian.Uint64(data)
}
// GetHeadHeaderHash retrieves the hash of the current canonical head block's
// header. The difference between this and GetHeadBlockHash is that whereas the
// last block hash is only updated upon a full block import, the last header
// hash is updated already at header import, allowing head tracking for the
// light synchronization mechanism.
func GetHeadHeaderHash(db ethdb.Database) common.Hash {
data, _ := db.Get(headHeaderKey)
if len(data) == 0 {
return common.Hash{}
}
return common.BytesToHash(data)
}
// GetHeadBlockHash retrieves the hash of the current canonical head block.
func GetHeadBlockHash(db ethdb.Database) common.Hash {
data, _ := db.Get(headBlockKey)
if len(data) == 0 {
return common.Hash{}
}
return common.BytesToHash(data)
}
// GetHeadFastBlockHash retrieves the hash of the current canonical head block during
// fast synchronization. The difference between this and GetHeadBlockHash is that
// whereas the last block hash is only updated upon a full block import, the last
// fast hash is updated when importing pre-processed blocks.
func GetHeadFastBlockHash(db ethdb.Database) common.Hash {
data, _ := db.Get(headFastKey)
if len(data) == 0 {
return common.Hash{}
}
return common.BytesToHash(data)
}
// GetHeaderRLP retrieves a block header in its raw RLP database encoding, or nil
// if the header's not found.
func GetHeaderRLP(db ethdb.Database, hash common.Hash, number uint64) rlp.RawValue {
data, _ := db.Get(append(append(headerPrefix, encodeBlockNumber(number)...), hash.Bytes()...))
if len(data) == 0 {
data, _ = db.Get(append(append(oldBlockPrefix, hash.Bytes()...), oldHeaderSuffix...))
}
return data
}
// GetHeader retrieves the block header corresponding to the hash, nil if none
// found.
func GetHeader(db ethdb.Database, hash common.Hash, number uint64) *types.Header {
data := GetHeaderRLP(db, hash, number)
if len(data) == 0 {
return nil
}
header := new(types.Header)
if err := rlp.Decode(bytes.NewReader(data), header); err != nil {
log.Error("Invalid block header RLP", "hash", hash, "err", err)
return nil
}
return header
}
// GetBodyRLP retrieves the block body (transactions and uncles) in RLP encoding.
func GetBodyRLP(db ethdb.Database, hash common.Hash, number uint64) rlp.RawValue {
data, _ := db.Get(append(append(bodyPrefix, encodeBlockNumber(number)...), hash.Bytes()...))
if len(data) == 0 {
data, _ = db.Get(append(append(oldBlockPrefix, hash.Bytes()...), oldBodySuffix...))
}
return data
}
// GetBody retrieves the block body (transactons, uncles) corresponding to the
// hash, nil if none found.
func GetBody(db ethdb.Database, hash common.Hash, number uint64) *types.Body {
data := GetBodyRLP(db, hash, number)
if len(data) == 0 {
return nil
}
body := new(types.Body)
if err := rlp.Decode(bytes.NewReader(data), body); err != nil {
log.Error("Invalid block body RLP", "hash", hash, "err", err)
return nil
}
return body
}
// GetTd retrieves a block's total difficulty corresponding to the hash, nil if
// none found.
func GetTd(db ethdb.Database, hash common.Hash, number uint64) *big.Int {
data, _ := db.Get(append(append(append(headerPrefix, encodeBlockNumber(number)...), hash[:]...), tdSuffix...))
if len(data) == 0 {
data, _ = db.Get(append(append(oldBlockPrefix, hash.Bytes()...), oldTdSuffix...))
if len(data) == 0 {
return nil
}
}
td := new(big.Int)
if err := rlp.Decode(bytes.NewReader(data), td); err != nil {
log.Error("Invalid block total difficulty RLP", "hash", hash, "err", err)
return nil
}
return td
}
// GetBlock retrieves an entire block corresponding to the hash, assembling it
// back from the stored header and body. If either the header or body could not
// be retrieved nil is returned.
//
// Note, due to concurrent download of header and block body the header and thus
// canonical hash can be stored in the database but the body data not (yet).
func GetBlock(db ethdb.Database, hash common.Hash, number uint64) *types.Block {
// Retrieve the block header and body contents
header := GetHeader(db, hash, number)
if header == nil {
return nil
}
body := GetBody(db, hash, number)
if body == nil {
return nil
}
// Reassemble the block and return
return types.NewBlockWithHeader(header).WithBody(body.Transactions, body.Uncles)
}
// GetBlockReceipts retrieves the receipts generated by the transactions included
// in a block given by its hash.
func GetBlockReceipts(db ethdb.Database, hash common.Hash, number uint64) types.Receipts {
data, _ := db.Get(append(append(blockReceiptsPrefix, encodeBlockNumber(number)...), hash[:]...))
if len(data) == 0 {
data, _ = db.Get(append(oldBlockReceiptsPrefix, hash.Bytes()...))
if len(data) == 0 {
return nil
}
}
storageReceipts := []*types.ReceiptForStorage{}
if err := rlp.DecodeBytes(data, &storageReceipts); err != nil {
log.Error("Invalid receipt array RLP", "hash", hash, "err", err)
return nil
}
receipts := make(types.Receipts, len(storageReceipts))
for i, receipt := range storageReceipts {
receipts[i] = (*types.Receipt)(receipt)
}
return receipts
}
// GetTransaction retrieves a specific transaction from the database, along with
// its added positional metadata.
func GetTransaction(db ethdb.Database, hash common.Hash) (*types.Transaction, common.Hash, uint64, uint64) {
// Retrieve the transaction itself from the database
data, _ := db.Get(hash.Bytes())
if len(data) == 0 {
return nil, common.Hash{}, 0, 0
}
var tx types.Transaction
if err := rlp.DecodeBytes(data, &tx); err != nil {
return nil, common.Hash{}, 0, 0
}
// Retrieve the blockchain positional metadata
data, _ = db.Get(append(hash.Bytes(), txMetaSuffix...))
if len(data) == 0 {
return nil, common.Hash{}, 0, 0
}
var meta struct {
BlockHash common.Hash
BlockIndex uint64
Index uint64
}
if err := rlp.DecodeBytes(data, &meta); err != nil {
return nil, common.Hash{}, 0, 0
}
return &tx, meta.BlockHash, meta.BlockIndex, meta.Index
}
// GetReceipt returns a receipt by hash
func GetReceipt(db ethdb.Database, hash common.Hash) *types.Receipt {
data, _ := db.Get(append(receiptsPrefix, hash[:]...))
if len(data) == 0 {
return nil
}
var receipt types.ReceiptForStorage
err := rlp.DecodeBytes(data, &receipt)
if err != nil {
log.Error("Invalid receipt RLP", "hash", hash, "err", err)
}
return (*types.Receipt)(&receipt)
}
// WriteCanonicalHash stores the canonical hash for the given block number.
func WriteCanonicalHash(db ethdb.Database, hash common.Hash, number uint64) error {
key := append(append(headerPrefix, encodeBlockNumber(number)...), numSuffix...)
if err := db.Put(key, hash.Bytes()); err != nil {
log.Crit("Failed to store number to hash mapping", "err", err)
}
return nil
}
// WriteHeadHeaderHash stores the head header's hash.
func WriteHeadHeaderHash(db ethdb.Database, hash common.Hash) error {
if err := db.Put(headHeaderKey, hash.Bytes()); err != nil {
log.Crit("Failed to store last header's hash", "err", err)
}
return nil
}
// WriteHeadBlockHash stores the head block's hash.
func WriteHeadBlockHash(db ethdb.Database, hash common.Hash) error {
if err := db.Put(headBlockKey, hash.Bytes()); err != nil {
log.Crit("Failed to store last block's hash", "err", err)
}
return nil
}
// WriteHeadFastBlockHash stores the fast head block's hash.
func WriteHeadFastBlockHash(db ethdb.Database, hash common.Hash) error {
if err := db.Put(headFastKey, hash.Bytes()); err != nil {
log.Crit("Failed to store last fast block's hash", "err", err)
}
return nil
}
// WriteHeader serializes a block header into the database.
func WriteHeader(db ethdb.Database, header *types.Header) error {
data, err := rlp.EncodeToBytes(header)
if err != nil {
return err
}
hash := header.Hash().Bytes()
num := header.Number.Uint64()
encNum := encodeBlockNumber(num)
key := append(blockHashPrefix, hash...)
if err := db.Put(key, encNum); err != nil {
log.Crit("Failed to store hash to number mapping", "err", err)
}
key = append(append(headerPrefix, encNum...), hash...)
if err := db.Put(key, data); err != nil {
log.Crit("Failed to store header", "err", err)
}
return nil
}
// WriteBody serializes the body of a block into the database.
func WriteBody(db ethdb.Database, hash common.Hash, number uint64, body *types.Body) error {
data, err := rlp.EncodeToBytes(body)
if err != nil {
return err
}
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return WriteBodyRLP(db, hash, number, data)
}
// WriteBodyRLP writes a serialized body of a block into the database.
func WriteBodyRLP(db ethdb.Database, hash common.Hash, number uint64, rlp rlp.RawValue) error {
key := append(append(bodyPrefix, encodeBlockNumber(number)...), hash.Bytes()...)
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if err := db.Put(key, rlp); err != nil {
log.Crit("Failed to store block body", "err", err)
}
return nil
}
// WriteTd serializes the total difficulty of a block into the database.
func WriteTd(db ethdb.Database, hash common.Hash, number uint64, td *big.Int) error {
data, err := rlp.EncodeToBytes(td)
if err != nil {
return err
}
key := append(append(append(headerPrefix, encodeBlockNumber(number)...), hash.Bytes()...), tdSuffix...)
if err := db.Put(key, data); err != nil {
log.Crit("Failed to store block total difficulty", "err", err)
}
return nil
}
// WriteBlock serializes a block into the database, header and body separately.
func WriteBlock(db ethdb.Database, block *types.Block) error {
// Store the body first to retain database consistency
if err := WriteBody(db, block.Hash(), block.NumberU64(), block.Body()); err != nil {
return err
}
// Store the header too, signaling full block ownership
if err := WriteHeader(db, block.Header()); err != nil {
return err
}
return nil
}
// WriteBlockReceipts stores all the transaction receipts belonging to a block
// as a single receipt slice. This is used during chain reorganisations for
// rescheduling dropped transactions.
func WriteBlockReceipts(db ethdb.Database, hash common.Hash, number uint64, receipts types.Receipts) error {
// Convert the receipts into their storage form and serialize them
storageReceipts := make([]*types.ReceiptForStorage, len(receipts))
for i, receipt := range receipts {
storageReceipts[i] = (*types.ReceiptForStorage)(receipt)
}
bytes, err := rlp.EncodeToBytes(storageReceipts)
if err != nil {
return err
}
// Store the flattened receipt slice
key := append(append(blockReceiptsPrefix, encodeBlockNumber(number)...), hash.Bytes()...)
if err := db.Put(key, bytes); err != nil {
log.Crit("Failed to store block receipts", "err", err)
}
return nil
}
// WriteTransactions stores the transactions associated with a specific block
// into the given database. Beside writing the transaction, the function also
// stores a metadata entry along with the transaction, detailing the position
// of this within the blockchain.
func WriteTransactions(db ethdb.Database, block *types.Block) error {
batch := db.NewBatch()
// Iterate over each transaction and encode it with its metadata
for i, tx := range block.Transactions() {
// Encode and queue up the transaction for storage
data, err := rlp.EncodeToBytes(tx)
if err != nil {
return err
}
if err = batch.Put(tx.Hash().Bytes(), data); err != nil {
return err
}
// Encode and queue up the transaction metadata for storage
meta := struct {
BlockHash common.Hash
BlockIndex uint64
Index uint64
}{
BlockHash: block.Hash(),
BlockIndex: block.NumberU64(),
Index: uint64(i),
}
data, err = rlp.EncodeToBytes(meta)
if err != nil {
return err
}
if err := batch.Put(append(tx.Hash().Bytes(), txMetaSuffix...), data); err != nil {
return err
}
}
// Write the scheduled data into the database
if err := batch.Write(); err != nil {
log.Crit("Failed to store transactions", "err", err)
}
return nil
}
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// WriteReceipt stores a single transaction receipt into the database.
func WriteReceipt(db ethdb.Database, receipt *types.Receipt) error {
storageReceipt := (*types.ReceiptForStorage)(receipt)
data, err := rlp.EncodeToBytes(storageReceipt)
if err != nil {
return err
}
return db.Put(append(receiptsPrefix, receipt.TxHash.Bytes()...), data)
}
// WriteReceipts stores a batch of transaction receipts into the database.
func WriteReceipts(db ethdb.Database, receipts types.Receipts) error {
batch := db.NewBatch()
// Iterate over all the receipts and queue them for database injection
for _, receipt := range receipts {
storageReceipt := (*types.ReceiptForStorage)(receipt)
data, err := rlp.EncodeToBytes(storageReceipt)
if err != nil {
return err
}
if err := batch.Put(append(receiptsPrefix, receipt.TxHash.Bytes()...), data); err != nil {
return err
}
}
// Write the scheduled data into the database
if err := batch.Write(); err != nil {
log.Crit("Failed to store receipts", "err", err)
}
return nil
}
// DeleteCanonicalHash removes the number to hash canonical mapping.
func DeleteCanonicalHash(db ethdb.Database, number uint64) {
db.Delete(append(append(headerPrefix, encodeBlockNumber(number)...), numSuffix...))
}
// DeleteHeader removes all block header data associated with a hash.
func DeleteHeader(db ethdb.Database, hash common.Hash, number uint64) {
db.Delete(append(blockHashPrefix, hash.Bytes()...))
db.Delete(append(append(headerPrefix, encodeBlockNumber(number)...), hash.Bytes()...))
}
// DeleteBody removes all block body data associated with a hash.
func DeleteBody(db ethdb.Database, hash common.Hash, number uint64) {
db.Delete(append(append(bodyPrefix, encodeBlockNumber(number)...), hash.Bytes()...))
}
// DeleteTd removes all block total difficulty data associated with a hash.
func DeleteTd(db ethdb.Database, hash common.Hash, number uint64) {
db.Delete(append(append(append(headerPrefix, encodeBlockNumber(number)...), hash.Bytes()...), tdSuffix...))
}
// DeleteBlock removes all block data associated with a hash.
func DeleteBlock(db ethdb.Database, hash common.Hash, number uint64) {
DeleteBlockReceipts(db, hash, number)
DeleteHeader(db, hash, number)
DeleteBody(db, hash, number)
DeleteTd(db, hash, number)
}
// DeleteBlockReceipts removes all receipt data associated with a block hash.
func DeleteBlockReceipts(db ethdb.Database, hash common.Hash, number uint64) {
db.Delete(append(append(blockReceiptsPrefix, encodeBlockNumber(number)...), hash.Bytes()...))
}
// DeleteTransaction removes all transaction data associated with a hash.
func DeleteTransaction(db ethdb.Database, hash common.Hash) {
db.Delete(hash.Bytes())
db.Delete(append(hash.Bytes(), txMetaSuffix...))
}
// DeleteReceipt removes all receipt data associated with a transaction hash.
func DeleteReceipt(db ethdb.Database, hash common.Hash) {
db.Delete(append(receiptsPrefix, hash.Bytes()...))
}
// returns a formatted MIP mapped key by adding prefix, canonical number and level
//
// ex. fn(98, 1000) = (prefix || 1000 || 0)
func mipmapKey(num, level uint64) []byte {
lkey := make([]byte, 8)
binary.BigEndian.PutUint64(lkey, level)
key := new(big.Int).SetUint64(num / level * level)
return append(mipmapPre, append(lkey, key.Bytes()...)...)
}
// WriteMapmapBloom writes each address included in the receipts' logs to the
// MIP bloom bin.
func WriteMipmapBloom(db ethdb.Database, number uint64, receipts types.Receipts) error {
mipmapBloomMu.Lock()
defer mipmapBloomMu.Unlock()
batch := db.NewBatch()
for _, level := range MIPMapLevels {
key := mipmapKey(number, level)
bloomDat, _ := db.Get(key)
bloom := types.BytesToBloom(bloomDat)
for _, receipt := range receipts {
for _, log := range receipt.Logs {
bloom.Add(log.Address.Big())
}
}
batch.Put(key, bloom.Bytes())
}
if err := batch.Write(); err != nil {
return fmt.Errorf("mipmap write fail for: %d: %v", number, err)
}
return nil
}
// GetMipmapBloom returns a bloom filter using the number and level as input
// parameters. For available levels see MIPMapLevels.
func GetMipmapBloom(db ethdb.Database, number, level uint64) types.Bloom {
bloomDat, _ := db.Get(mipmapKey(number, level))
return types.BytesToBloom(bloomDat)
}
// PreimageTable returns a Database instance with the key prefix for preimage entries.
func PreimageTable(db ethdb.Database) ethdb.Database {
return ethdb.NewTable(db, preimagePrefix)
}
// WritePreimages writes the provided set of preimages to the database. `number` is the
// current block number, and is used for debug messages only.
func WritePreimages(db ethdb.Database, number uint64, preimages map[common.Hash][]byte) error {
table := PreimageTable(db)
batch := table.NewBatch()
hitCount := 0
for hash, preimage := range preimages {
if _, err := table.Get(hash.Bytes()); err != nil {
batch.Put(hash.Bytes(), preimage)
hitCount++
}
}
preimageCounter.Inc(int64(len(preimages)))
preimageHitCounter.Inc(int64(hitCount))
if hitCount > 0 {
if err := batch.Write(); err != nil {
return fmt.Errorf("preimage write fail for block %d: %v", number, err)
}
}
return nil
}
// GetBlockChainVersion reads the version number from db.
func GetBlockChainVersion(db ethdb.Database) int {
var vsn uint
enc, _ := db.Get([]byte("BlockchainVersion"))
rlp.DecodeBytes(enc, &vsn)
return int(vsn)
}
// WriteBlockChainVersion writes vsn as the version number to db.
func WriteBlockChainVersion(db ethdb.Database, vsn int) {
enc, _ := rlp.EncodeToBytes(uint(vsn))
db.Put([]byte("BlockchainVersion"), enc)
}
// WriteChainConfig writes the chain config settings to the database.
func WriteChainConfig(db ethdb.Database, hash common.Hash, cfg *params.ChainConfig) error {
// short circuit and ignore if nil config. GetChainConfig
// will return a default.
if cfg == nil {
return nil
}
jsonChainConfig, err := json.Marshal(cfg)
if err != nil {
return err
}
return db.Put(append(configPrefix, hash[:]...), jsonChainConfig)
}
// GetChainConfig will fetch the network settings based on the given hash.
func GetChainConfig(db ethdb.Database, hash common.Hash) (*params.ChainConfig, error) {
jsonChainConfig, _ := db.Get(append(configPrefix, hash[:]...))
if len(jsonChainConfig) == 0 {
return nil, ChainConfigNotFoundErr
}
var config params.ChainConfig
if err := json.Unmarshal(jsonChainConfig, &config); err != nil {
return nil, err
}
return &config, nil
}
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// FindCommonAncestor returns the last common ancestor of two block headers
func FindCommonAncestor(db ethdb.Database, a, b *types.Header) *types.Header {
for bn := b.Number.Uint64(); a.Number.Uint64() > bn; {
a = GetHeader(db, a.ParentHash, a.Number.Uint64()-1)
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if a == nil {
return nil
}
}
for an := a.Number.Uint64(); an < b.Number.Uint64(); {
b = GetHeader(db, b.ParentHash, b.Number.Uint64()-1)
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if b == nil {
return nil
}
}
for a.Hash() != b.Hash() {
a = GetHeader(db, a.ParentHash, a.Number.Uint64()-1)
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if a == nil {
return nil
}
b = GetHeader(db, b.ParentHash, b.Number.Uint64()-1)
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if b == nil {
return nil
}
}
return a
}