mirror of https://github.com/status-im/op-geth.git
122 lines
3.5 KiB
Go
122 lines
3.5 KiB
Go
// Copyright 2019 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 snapshot
|
|
|
|
import (
|
|
"bytes"
|
|
|
|
"github.com/ethereum/go-ethereum/common"
|
|
)
|
|
|
|
// binaryAccountIterator is a simplistic iterator to step over the accounts in
|
|
// a snapshot, which may or may npt be composed of multiple layers. Performance
|
|
// wise this iterator is slow, it's meant for cross validating the fast one,
|
|
type binaryAccountIterator struct {
|
|
a AccountIterator
|
|
b AccountIterator
|
|
aDone bool
|
|
bDone bool
|
|
k common.Hash
|
|
fail error
|
|
}
|
|
|
|
// newBinaryAccountIterator creates a simplistic account iterator to step over
|
|
// all the accounts in a slow, but eaily verifiable way.
|
|
func (dl *diffLayer) newBinaryAccountIterator() AccountIterator {
|
|
parent, ok := dl.parent.(*diffLayer)
|
|
if !ok {
|
|
// parent is the disk layer
|
|
l := &binaryAccountIterator{
|
|
a: dl.AccountIterator(common.Hash{}),
|
|
b: dl.Parent().AccountIterator(common.Hash{}),
|
|
}
|
|
l.aDone = !l.a.Next()
|
|
l.bDone = !l.b.Next()
|
|
return l
|
|
}
|
|
l := &binaryAccountIterator{
|
|
a: dl.AccountIterator(common.Hash{}),
|
|
b: parent.newBinaryAccountIterator(),
|
|
}
|
|
l.aDone = !l.a.Next()
|
|
l.bDone = !l.b.Next()
|
|
return l
|
|
}
|
|
|
|
// Next steps the iterator forward one element, returning false if exhausted,
|
|
// or an error if iteration failed for some reason (e.g. root being iterated
|
|
// becomes stale and garbage collected).
|
|
func (it *binaryAccountIterator) Next() bool {
|
|
if it.aDone && it.bDone {
|
|
return false
|
|
}
|
|
first:
|
|
if it.aDone {
|
|
it.k = it.b.Hash()
|
|
it.bDone = !it.b.Next()
|
|
return true
|
|
}
|
|
if it.bDone {
|
|
it.k = it.a.Hash()
|
|
it.aDone = !it.a.Next()
|
|
return true
|
|
}
|
|
nextA, nextB := it.a.Hash(), it.b.Hash()
|
|
if diff := bytes.Compare(nextA[:], nextB[:]); diff < 0 {
|
|
it.aDone = !it.a.Next()
|
|
it.k = nextA
|
|
return true
|
|
} else if diff == 0 {
|
|
// Now we need to advance one of them
|
|
it.aDone = !it.a.Next()
|
|
goto first
|
|
}
|
|
it.bDone = !it.b.Next()
|
|
it.k = nextB
|
|
return true
|
|
}
|
|
|
|
// Error returns any failure that occurred during iteration, which might have
|
|
// caused a premature iteration exit (e.g. snapshot stack becoming stale).
|
|
func (it *binaryAccountIterator) Error() error {
|
|
return it.fail
|
|
}
|
|
|
|
// Hash returns the hash of the account the iterator is currently at.
|
|
func (it *binaryAccountIterator) Hash() common.Hash {
|
|
return it.k
|
|
}
|
|
|
|
// Account returns the RLP encoded slim account the iterator is currently at, or
|
|
// nil if the iterated snapshot stack became stale (you can check Error after
|
|
// to see if it failed or not).
|
|
func (it *binaryAccountIterator) Account() []byte {
|
|
// The topmost iterator must be `diffAccountIterator`
|
|
blob, err := it.a.(*diffAccountIterator).layer.AccountRLP(it.k)
|
|
if err != nil {
|
|
it.fail = err
|
|
return nil
|
|
}
|
|
return blob
|
|
}
|
|
|
|
// Release recursively releases all the iterators in the stack.
|
|
func (it *binaryAccountIterator) Release() {
|
|
it.a.Release()
|
|
it.b.Release()
|
|
}
|