go-ethereum/les/sync.go

57 lines
2.0 KiB
Go

// Copyright 2016 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 les
import (
"time"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/rawdb"
"github.com/ethereum/go-ethereum/les/downloader"
"github.com/ethereum/go-ethereum/log"
)
// synchronise tries to sync up our local chain with a remote peer.
func (h *clientHandler) synchronise(peer *serverPeer) {
// Short circuit if the peer is nil.
if peer == nil {
return
}
// Make sure the peer's TD is higher than our own.
latest := h.backend.blockchain.CurrentHeader()
currentTd := rawdb.ReadTd(h.backend.chainDb, latest.Hash(), latest.Number.Uint64())
if currentTd != nil && peer.Td().Cmp(currentTd) < 0 {
return
}
// Notify testing framework if syncing has completed (for testing purpose).
defer func() {
if h.syncEnd != nil {
h.syncEnd(h.backend.blockchain.CurrentHeader())
}
}()
start := time.Now()
if h.syncStart != nil {
h.syncStart(h.backend.blockchain.CurrentHeader())
}
// Fetch the remaining block headers based on the current chain header.
if err := h.downloader.Synchronise(peer.id, peer.Head(), peer.Td(), downloader.LightSync); err != nil {
log.Debug("Synchronise failed", "reason", err)
return
}
log.Debug("Synchronise finished", "elapsed", common.PrettyDuration(time.Since(start)))
}