1654 lines
59 KiB
Go
1654 lines
59 KiB
Go
// Copyright 2015 The go-ethereum Authors
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// This file is part of the go-ethereum library.
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//
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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
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// 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
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU Lesser General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public License
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// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
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// Package downloader contains the manual full chain synchronisation.
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package downloader
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import (
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"errors"
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"math"
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"math/big"
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"strings"
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"sync"
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"sync/atomic"
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"time"
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"github.com/ethereum/go-ethereum/common"
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"github.com/ethereum/go-ethereum/core/types"
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"github.com/ethereum/go-ethereum/ethdb"
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"github.com/ethereum/go-ethereum/event"
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"github.com/ethereum/go-ethereum/logger"
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"github.com/ethereum/go-ethereum/logger/glog"
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"github.com/rcrowley/go-metrics"
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)
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var (
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MaxHashFetch = 512 // Amount of hashes to be fetched per retrieval request
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MaxBlockFetch = 128 // Amount of blocks to be fetched per retrieval request
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MaxHeaderFetch = 192 // Amount of block headers to be fetched per retrieval request
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MaxBodyFetch = 128 // Amount of block bodies to be fetched per retrieval request
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MaxReceiptFetch = 256 // Amount of transaction receipts to allow fetching per request
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MaxStateFetch = 384 // Amount of node state values to allow fetching per request
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hashTTL = 5 * time.Second // [eth/61] Time it takes for a hash request to time out
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blockSoftTTL = 3 * time.Second // [eth/61] Request completion threshold for increasing or decreasing a peer's bandwidth
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blockHardTTL = 3 * blockSoftTTL // [eth/61] Maximum time allowance before a block request is considered expired
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headerTTL = 5 * time.Second // [eth/62] Time it takes for a header request to time out
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bodySoftTTL = 3 * time.Second // [eth/62] Request completion threshold for increasing or decreasing a peer's bandwidth
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bodyHardTTL = 3 * bodySoftTTL // [eth/62] Maximum time allowance before a block body request is considered expired
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receiptSoftTTL = 3 * time.Second // [eth/63] Request completion threshold for increasing or decreasing a peer's bandwidth
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receiptHardTTL = 3 * receiptSoftTTL // [eth/63] Maximum time allowance before a receipt request is considered expired
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stateSoftTTL = 2 * time.Second // [eth/63] Request completion threshold for increasing or decreasing a peer's bandwidth
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stateHardTTL = 3 * stateSoftTTL // [eth/63] Maximum time allowance before a node data request is considered expired
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maxQueuedHashes = 256 * 1024 // [eth/61] Maximum number of hashes to queue for import (DOS protection)
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maxQueuedHeaders = 256 * 1024 // [eth/62] Maximum number of headers to queue for import (DOS protection)
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maxQueuedStates = 256 * 1024 // [eth/63] Maximum number of state requests to queue (DOS protection)
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maxResultsProcess = 256 // Number of download results to import at once into the chain
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headerCheckFrequency = 100 // Verification frequency of the downloaded headers during fast sync
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minCheckedHeaders = 2048 // Number of headers to verify fully when approaching the chain head
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minFullBlocks = 1024 // Number of blocks to retrieve fully even in fast sync
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)
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var (
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errBusy = errors.New("busy")
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errUnknownPeer = errors.New("peer is unknown or unhealthy")
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errBadPeer = errors.New("action from bad peer ignored")
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errStallingPeer = errors.New("peer is stalling")
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errNoPeers = errors.New("no peers to keep download active")
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errPendingQueue = errors.New("pending items in queue")
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errTimeout = errors.New("timeout")
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errEmptyHashSet = errors.New("empty hash set by peer")
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errEmptyHeaderSet = errors.New("empty header set by peer")
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errPeersUnavailable = errors.New("no peers available or all tried for download")
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errAlreadyInPool = errors.New("hash already in pool")
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errInvalidChain = errors.New("retrieved hash chain is invalid")
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errInvalidBlock = errors.New("retrieved block is invalid")
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errInvalidBody = errors.New("retrieved block body is invalid")
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errInvalidReceipt = errors.New("retrieved receipt is invalid")
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errCancelHashFetch = errors.New("hash download canceled (requested)")
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errCancelBlockFetch = errors.New("block download canceled (requested)")
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errCancelHeaderFetch = errors.New("block header download canceled (requested)")
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errCancelBodyFetch = errors.New("block body download canceled (requested)")
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errCancelReceiptFetch = errors.New("receipt download canceled (requested)")
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errNoSyncActive = errors.New("no sync active")
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)
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type Downloader struct {
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mode SyncMode // Synchronisation mode defining the strategies used
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mux *event.TypeMux // Event multiplexer to announce sync operation events
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queue *queue // Scheduler for selecting the hashes to download
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peers *peerSet // Set of active peers from which download can proceed
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interrupt int32 // Atomic boolean to signal termination
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// Statistics
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syncStatsChainOrigin uint64 // Origin block number where syncing started at
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syncStatsChainHeight uint64 // Highest block number known when syncing started
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syncStatsStateTotal uint64 // Total number of node state entries known so far
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syncStatsStateDone uint64 // Number of state trie entries already pulled
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syncStatsLock sync.RWMutex // Lock protecting the sync stats fields
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// Callbacks
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hasHeader headerCheckFn // Checks if a header is present in the chain
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hasBlock blockCheckFn // Checks if a block is present in the chain
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getHeader headerRetrievalFn // Retrieves a header from the chain
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getBlock blockRetrievalFn // Retrieves a block from the chain
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headHeader headHeaderRetrievalFn // Retrieves the head header from the chain
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headBlock headBlockRetrievalFn // Retrieves the head block from the chain
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headFastBlock headFastBlockRetrievalFn // Retrieves the head fast-sync block from the chain
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commitHeadBlock headBlockCommitterFn // Commits a manually assembled block as the chain head
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getTd tdRetrievalFn // Retrieves the TD of a block from the chain
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insertHeaders headerChainInsertFn // Injects a batch of headers into the chain
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insertBlocks blockChainInsertFn // Injects a batch of blocks into the chain
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insertReceipts receiptChainInsertFn // Injects a batch of blocks and their receipts into the chain
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rollback chainRollbackFn // Removes a batch of recently added chain links
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dropPeer peerDropFn // Drops a peer for misbehaving
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// Status
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synchroniseMock func(id string, hash common.Hash) error // Replacement for synchronise during testing
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synchronising int32
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processing int32
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notified int32
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// Channels
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newPeerCh chan *peer
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hashCh chan dataPack // [eth/61] Channel receiving inbound hashes
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blockCh chan dataPack // [eth/61] Channel receiving inbound blocks
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headerCh chan dataPack // [eth/62] Channel receiving inbound block headers
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bodyCh chan dataPack // [eth/62] Channel receiving inbound block bodies
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receiptCh chan dataPack // [eth/63] Channel receiving inbound receipts
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stateCh chan dataPack // [eth/63] Channel receiving inbound node state data
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blockWakeCh chan bool // [eth/61] Channel to signal the block fetcher of new tasks
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bodyWakeCh chan bool // [eth/62] Channel to signal the block body fetcher of new tasks
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receiptWakeCh chan bool // [eth/63] Channel to signal the receipt fetcher of new tasks
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stateWakeCh chan bool // [eth/63] Channel to signal the state fetcher of new tasks
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cancelCh chan struct{} // Channel to cancel mid-flight syncs
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cancelLock sync.RWMutex // Lock to protect the cancel channel in delivers
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// Testing hooks
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syncInitHook func(uint64, uint64) // Method to call upon initiating a new sync run
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bodyFetchHook func([]*types.Header) // Method to call upon starting a block body fetch
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receiptFetchHook func([]*types.Header) // Method to call upon starting a receipt fetch
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chainInsertHook func([]*fetchResult) // Method to call upon inserting a chain of blocks (possibly in multiple invocations)
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}
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// New creates a new downloader to fetch hashes and blocks from remote peers.
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func New(mode SyncMode, stateDb ethdb.Database, mux *event.TypeMux, hasHeader headerCheckFn, hasBlock blockCheckFn, getHeader headerRetrievalFn,
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getBlock blockRetrievalFn, headHeader headHeaderRetrievalFn, headBlock headBlockRetrievalFn, headFastBlock headFastBlockRetrievalFn,
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commitHeadBlock headBlockCommitterFn, getTd tdRetrievalFn, insertHeaders headerChainInsertFn, insertBlocks blockChainInsertFn,
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insertReceipts receiptChainInsertFn, rollback chainRollbackFn, dropPeer peerDropFn) *Downloader {
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return &Downloader{
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mode: mode,
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mux: mux,
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queue: newQueue(stateDb),
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peers: newPeerSet(),
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hasHeader: hasHeader,
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hasBlock: hasBlock,
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getHeader: getHeader,
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getBlock: getBlock,
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headHeader: headHeader,
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headBlock: headBlock,
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headFastBlock: headFastBlock,
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commitHeadBlock: commitHeadBlock,
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getTd: getTd,
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insertHeaders: insertHeaders,
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insertBlocks: insertBlocks,
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insertReceipts: insertReceipts,
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rollback: rollback,
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dropPeer: dropPeer,
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newPeerCh: make(chan *peer, 1),
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hashCh: make(chan dataPack, 1),
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blockCh: make(chan dataPack, 1),
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headerCh: make(chan dataPack, 1),
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bodyCh: make(chan dataPack, 1),
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receiptCh: make(chan dataPack, 1),
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stateCh: make(chan dataPack, 1),
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blockWakeCh: make(chan bool, 1),
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bodyWakeCh: make(chan bool, 1),
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receiptWakeCh: make(chan bool, 1),
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stateWakeCh: make(chan bool, 1),
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}
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}
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// Boundaries retrieves the synchronisation boundaries, specifically the origin
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// block where synchronisation started at (may have failed/suspended) and the
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// latest known block which the synchonisation targets.
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func (d *Downloader) Boundaries() (uint64, uint64) {
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d.syncStatsLock.RLock()
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defer d.syncStatsLock.RUnlock()
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return d.syncStatsChainOrigin, d.syncStatsChainHeight
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}
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// Synchronising returns whether the downloader is currently retrieving blocks.
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func (d *Downloader) Synchronising() bool {
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return atomic.LoadInt32(&d.synchronising) > 0
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}
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// RegisterPeer injects a new download peer into the set of block source to be
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// used for fetching hashes and blocks from.
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func (d *Downloader) RegisterPeer(id string, version int, head common.Hash,
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getRelHashes relativeHashFetcherFn, getAbsHashes absoluteHashFetcherFn, getBlocks blockFetcherFn, // eth/61 callbacks, remove when upgrading
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getRelHeaders relativeHeaderFetcherFn, getAbsHeaders absoluteHeaderFetcherFn, getBlockBodies blockBodyFetcherFn,
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getReceipts receiptFetcherFn, getNodeData stateFetcherFn) error {
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glog.V(logger.Detail).Infoln("Registering peer", id)
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if err := d.peers.Register(newPeer(id, version, head, getRelHashes, getAbsHashes, getBlocks, getRelHeaders, getAbsHeaders, getBlockBodies, getReceipts, getNodeData)); err != nil {
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glog.V(logger.Error).Infoln("Register failed:", err)
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return err
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}
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return nil
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}
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// UnregisterPeer remove a peer from the known list, preventing any action from
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// the specified peer. An effort is also made to return any pending fetches into
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// the queue.
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func (d *Downloader) UnregisterPeer(id string) error {
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glog.V(logger.Detail).Infoln("Unregistering peer", id)
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if err := d.peers.Unregister(id); err != nil {
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glog.V(logger.Error).Infoln("Unregister failed:", err)
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return err
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}
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d.queue.Revoke(id)
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return nil
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}
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// Synchronise tries to sync up our local block chain with a remote peer, both
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// adding various sanity checks as well as wrapping it with various log entries.
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func (d *Downloader) Synchronise(id string, head common.Hash, td *big.Int) {
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glog.V(logger.Detail).Infof("Attempting synchronisation: %v, head [%x…], TD %v", id, head[:4], td)
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switch err := d.synchronise(id, head, td); err {
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case nil:
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glog.V(logger.Detail).Infof("Synchronisation completed")
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case errBusy:
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glog.V(logger.Detail).Infof("Synchronisation already in progress")
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case errTimeout, errBadPeer, errStallingPeer, errEmptyHashSet, errEmptyHeaderSet, errPeersUnavailable, errInvalidChain:
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glog.V(logger.Debug).Infof("Removing peer %v: %v", id, err)
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d.dropPeer(id)
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case errPendingQueue:
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glog.V(logger.Debug).Infoln("Synchronisation aborted:", err)
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default:
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glog.V(logger.Warn).Infof("Synchronisation failed: %v", err)
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}
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}
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// synchronise will select the peer and use it for synchronising. If an empty string is given
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// it will use the best peer possible and synchronize if it's TD is higher than our own. If any of the
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// checks fail an error will be returned. This method is synchronous
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func (d *Downloader) synchronise(id string, hash common.Hash, td *big.Int) error {
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// Mock out the synchonisation if testing
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if d.synchroniseMock != nil {
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return d.synchroniseMock(id, hash)
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}
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// Make sure only one goroutine is ever allowed past this point at once
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if !atomic.CompareAndSwapInt32(&d.synchronising, 0, 1) {
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return errBusy
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}
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defer atomic.StoreInt32(&d.synchronising, 0)
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// Post a user notification of the sync (only once per session)
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if atomic.CompareAndSwapInt32(&d.notified, 0, 1) {
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glog.V(logger.Info).Infoln("Block synchronisation started")
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}
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// Abort if the queue still contains some leftover data
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if d.queue.GetHeadResult() != nil {
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return errPendingQueue
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}
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// Reset the queue, peer set and wake channels to clean any internal leftover state
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d.queue.Reset()
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d.peers.Reset()
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for _, ch := range []chan bool{d.blockWakeCh, d.bodyWakeCh, d.receiptWakeCh, d.stateWakeCh} {
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select {
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case <-ch:
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default:
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}
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}
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// Reset and ephemeral sync statistics
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d.syncStatsLock.Lock()
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d.syncStatsStateTotal = 0
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d.syncStatsStateDone = 0
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d.syncStatsLock.Unlock()
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// Create cancel channel for aborting mid-flight
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d.cancelLock.Lock()
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d.cancelCh = make(chan struct{})
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d.cancelLock.Unlock()
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// Retrieve the origin peer and initiate the downloading process
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p := d.peers.Peer(id)
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if p == nil {
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return errUnknownPeer
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}
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return d.syncWithPeer(p, hash, td)
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}
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/*
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// Has checks if the downloader knows about a particular hash, meaning that its
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// either already downloaded of pending retrieval.
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func (d *Downloader) Has(hash common.Hash) bool {
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return d.queue.Has(hash)
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}
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*/
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// syncWithPeer starts a block synchronization based on the hash chain from the
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// specified peer and head hash.
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func (d *Downloader) syncWithPeer(p *peer, hash common.Hash, td *big.Int) (err error) {
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d.mux.Post(StartEvent{})
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defer func() {
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// reset on error
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if err != nil {
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d.cancel()
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d.mux.Post(FailedEvent{err})
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} else {
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d.mux.Post(DoneEvent{})
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}
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}()
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glog.V(logger.Debug).Infof("Synchronising with the network using: %s [eth/%d]", p.id, p.version)
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defer func(start time.Time) {
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glog.V(logger.Debug).Infof("Synchronisation terminated after %v", time.Since(start))
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}(time.Now())
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switch {
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case p.version == 61:
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// Look up the sync boundaries: the common ancestor and the target block
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latest, err := d.fetchHeight61(p)
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if err != nil {
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return err
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}
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origin, err := d.findAncestor61(p)
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if err != nil {
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return err
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}
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d.syncStatsLock.Lock()
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if d.syncStatsChainHeight <= origin || d.syncStatsChainOrigin > origin {
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d.syncStatsChainOrigin = origin
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}
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d.syncStatsChainHeight = latest
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d.syncStatsLock.Unlock()
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// Initiate the sync using a concurrent hash and block retrieval algorithm
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if d.syncInitHook != nil {
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d.syncInitHook(origin, latest)
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}
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d.queue.Prepare(origin+1, d.mode, 0)
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errc := make(chan error, 2)
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go func() { errc <- d.fetchHashes61(p, td, origin+1) }()
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go func() { errc <- d.fetchBlocks61(origin + 1) }()
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// If any fetcher fails, cancel the other
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if err := <-errc; err != nil {
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d.cancel()
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<-errc
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return err
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}
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return <-errc
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case p.version >= 62:
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// Look up the sync boundaries: the common ancestor and the target block
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latest, err := d.fetchHeight(p)
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if err != nil {
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return err
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}
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origin, err := d.findAncestor(p)
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if err != nil {
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return err
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}
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d.syncStatsLock.Lock()
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if d.syncStatsChainHeight <= origin || d.syncStatsChainOrigin > origin {
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d.syncStatsChainOrigin = origin
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}
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d.syncStatsChainHeight = latest
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d.syncStatsLock.Unlock()
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// Initiate the sync using a concurrent header and content retrieval algorithm
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pivot := uint64(0)
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if latest > uint64(minFullBlocks) {
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pivot = latest - uint64(minFullBlocks)
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}
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d.queue.Prepare(origin+1, d.mode, pivot)
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if d.syncInitHook != nil {
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d.syncInitHook(origin, latest)
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}
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errc := make(chan error, 4)
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go func() { errc <- d.fetchHeaders(p, td, origin+1, latest) }() // Headers are always retrieved
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go func() { errc <- d.fetchBodies(origin + 1) }() // Bodies are retrieved during normal and fast sync
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go func() { errc <- d.fetchReceipts(origin + 1) }() // Receipts are retrieved during fast sync
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go func() { errc <- d.fetchNodeData() }() // Node state data is retrieved during fast sync
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// If any fetcher fails, cancel the others
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var fail error
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for i := 0; i < cap(errc); i++ {
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if err := <-errc; err != nil {
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if fail == nil {
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fail = err
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d.cancel()
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}
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}
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}
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return fail
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default:
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// Something very wrong, stop right here
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glog.V(logger.Error).Infof("Unsupported eth protocol: %d", p.version)
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return errBadPeer
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}
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return nil
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}
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// cancel cancels all of the operations and resets the queue. It returns true
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// if the cancel operation was completed.
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func (d *Downloader) cancel() {
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// Close the current cancel channel
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d.cancelLock.Lock()
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if d.cancelCh != nil {
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select {
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case <-d.cancelCh:
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// Channel was already closed
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default:
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close(d.cancelCh)
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}
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}
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d.cancelLock.Unlock()
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// Reset the queue
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d.queue.Reset()
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}
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// Terminate interrupts the downloader, canceling all pending operations.
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func (d *Downloader) Terminate() {
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atomic.StoreInt32(&d.interrupt, 1)
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d.cancel()
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}
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// fetchHeight61 retrieves the head block of the remote peer to aid in estimating
|
|
// the total time a pending synchronisation would take.
|
|
func (d *Downloader) fetchHeight61(p *peer) (uint64, error) {
|
|
glog.V(logger.Debug).Infof("%v: retrieving remote chain height", p)
|
|
|
|
// Request the advertised remote head block and wait for the response
|
|
go p.getBlocks([]common.Hash{p.head})
|
|
|
|
timeout := time.After(blockSoftTTL)
|
|
for {
|
|
select {
|
|
case <-d.cancelCh:
|
|
return 0, errCancelBlockFetch
|
|
|
|
case <-d.headerCh:
|
|
// Out of bounds eth/62 block headers received, ignore them
|
|
|
|
case <-d.bodyCh:
|
|
// Out of bounds eth/62 block bodies received, ignore them
|
|
|
|
case <-d.hashCh:
|
|
// Out of bounds hashes received, ignore them
|
|
|
|
case packet := <-d.blockCh:
|
|
// Discard anything not from the origin peer
|
|
if packet.PeerId() != p.id {
|
|
glog.V(logger.Debug).Infof("Received blocks from incorrect peer(%s)", packet.PeerId())
|
|
break
|
|
}
|
|
// Make sure the peer actually gave something valid
|
|
blocks := packet.(*blockPack).blocks
|
|
if len(blocks) != 1 {
|
|
glog.V(logger.Debug).Infof("%v: invalid number of head blocks: %d != 1", p, len(blocks))
|
|
return 0, errBadPeer
|
|
}
|
|
return blocks[0].NumberU64(), nil
|
|
|
|
case <-timeout:
|
|
glog.V(logger.Debug).Infof("%v: head block timeout", p)
|
|
return 0, errTimeout
|
|
}
|
|
}
|
|
}
|
|
|
|
// findAncestor61 tries to locate the common ancestor block of the local chain and
|
|
// a remote peers blockchain. In the general case when our node was in sync and
|
|
// on the correct chain, checking the top N blocks should already get us a match.
|
|
// In the rare scenario when we ended up on a long reorganization (i.e. none of
|
|
// the head blocks match), we do a binary search to find the common ancestor.
|
|
func (d *Downloader) findAncestor61(p *peer) (uint64, error) {
|
|
glog.V(logger.Debug).Infof("%v: looking for common ancestor", p)
|
|
|
|
// Request out head blocks to short circuit ancestor location
|
|
head := d.headBlock().NumberU64()
|
|
from := int64(head) - int64(MaxHashFetch) + 1
|
|
if from < 0 {
|
|
from = 0
|
|
}
|
|
go p.getAbsHashes(uint64(from), MaxHashFetch)
|
|
|
|
// Wait for the remote response to the head fetch
|
|
number, hash := uint64(0), common.Hash{}
|
|
timeout := time.After(hashTTL)
|
|
|
|
for finished := false; !finished; {
|
|
select {
|
|
case <-d.cancelCh:
|
|
return 0, errCancelHashFetch
|
|
|
|
case packet := <-d.hashCh:
|
|
// Discard anything not from the origin peer
|
|
if packet.PeerId() != p.id {
|
|
glog.V(logger.Debug).Infof("Received hashes from incorrect peer(%s)", packet.PeerId())
|
|
break
|
|
}
|
|
// Make sure the peer actually gave something valid
|
|
hashes := packet.(*hashPack).hashes
|
|
if len(hashes) == 0 {
|
|
glog.V(logger.Debug).Infof("%v: empty head hash set", p)
|
|
return 0, errEmptyHashSet
|
|
}
|
|
// Check if a common ancestor was found
|
|
finished = true
|
|
for i := len(hashes) - 1; i >= 0; i-- {
|
|
if d.hasBlock(hashes[i]) {
|
|
number, hash = uint64(from)+uint64(i), hashes[i]
|
|
break
|
|
}
|
|
}
|
|
|
|
case <-d.blockCh:
|
|
// Out of bounds blocks received, ignore them
|
|
|
|
case <-d.headerCh:
|
|
// Out of bounds eth/62 block headers received, ignore them
|
|
|
|
case <-d.bodyCh:
|
|
// Out of bounds eth/62 block bodies received, ignore them
|
|
|
|
case <-timeout:
|
|
glog.V(logger.Debug).Infof("%v: head hash timeout", p)
|
|
return 0, errTimeout
|
|
}
|
|
}
|
|
// If the head fetch already found an ancestor, return
|
|
if !common.EmptyHash(hash) {
|
|
glog.V(logger.Debug).Infof("%v: common ancestor: #%d [%x…]", p, number, hash[:4])
|
|
return number, nil
|
|
}
|
|
// Ancestor not found, we need to binary search over our chain
|
|
start, end := uint64(0), head
|
|
for start+1 < end {
|
|
// Split our chain interval in two, and request the hash to cross check
|
|
check := (start + end) / 2
|
|
|
|
timeout := time.After(hashTTL)
|
|
go p.getAbsHashes(uint64(check), 1)
|
|
|
|
// Wait until a reply arrives to this request
|
|
for arrived := false; !arrived; {
|
|
select {
|
|
case <-d.cancelCh:
|
|
return 0, errCancelHashFetch
|
|
|
|
case packet := <-d.hashCh:
|
|
// Discard anything not from the origin peer
|
|
if packet.PeerId() != p.id {
|
|
glog.V(logger.Debug).Infof("Received hashes from incorrect peer(%s)", packet.PeerId())
|
|
break
|
|
}
|
|
// Make sure the peer actually gave something valid
|
|
hashes := packet.(*hashPack).hashes
|
|
if len(hashes) != 1 {
|
|
glog.V(logger.Debug).Infof("%v: invalid search hash set (%d)", p, len(hashes))
|
|
return 0, errBadPeer
|
|
}
|
|
arrived = true
|
|
|
|
// Modify the search interval based on the response
|
|
block := d.getBlock(hashes[0])
|
|
if block == nil {
|
|
end = check
|
|
break
|
|
}
|
|
if block.NumberU64() != check {
|
|
glog.V(logger.Debug).Infof("%v: non requested hash #%d [%x…], instead of #%d", p, block.NumberU64(), block.Hash().Bytes()[:4], check)
|
|
return 0, errBadPeer
|
|
}
|
|
start = check
|
|
|
|
case <-d.blockCh:
|
|
// Out of bounds blocks received, ignore them
|
|
|
|
case <-d.headerCh:
|
|
// Out of bounds eth/62 block headers received, ignore them
|
|
|
|
case <-d.bodyCh:
|
|
// Out of bounds eth/62 block bodies received, ignore them
|
|
|
|
case <-timeout:
|
|
glog.V(logger.Debug).Infof("%v: search hash timeout", p)
|
|
return 0, errTimeout
|
|
}
|
|
}
|
|
}
|
|
return start, nil
|
|
}
|
|
|
|
// fetchHashes61 keeps retrieving hashes from the requested number, until no more
|
|
// are returned, potentially throttling on the way.
|
|
func (d *Downloader) fetchHashes61(p *peer, td *big.Int, from uint64) error {
|
|
glog.V(logger.Debug).Infof("%v: downloading hashes from #%d", p, from)
|
|
|
|
// Create a timeout timer, and the associated hash fetcher
|
|
request := time.Now() // time of the last fetch request
|
|
timeout := time.NewTimer(0) // timer to dump a non-responsive active peer
|
|
<-timeout.C // timeout channel should be initially empty
|
|
defer timeout.Stop()
|
|
|
|
getHashes := func(from uint64) {
|
|
glog.V(logger.Detail).Infof("%v: fetching %d hashes from #%d", p, MaxHashFetch, from)
|
|
|
|
go p.getAbsHashes(from, MaxHashFetch)
|
|
request = time.Now()
|
|
timeout.Reset(hashTTL)
|
|
}
|
|
// Start pulling hashes, until all are exhausted
|
|
getHashes(from)
|
|
gotHashes := false
|
|
|
|
for {
|
|
select {
|
|
case <-d.cancelCh:
|
|
return errCancelHashFetch
|
|
|
|
case <-d.headerCh:
|
|
// Out of bounds eth/62 block headers received, ignore them
|
|
|
|
case <-d.bodyCh:
|
|
// Out of bounds eth/62 block bodies received, ignore them
|
|
|
|
case packet := <-d.hashCh:
|
|
// Make sure the active peer is giving us the hashes
|
|
if packet.PeerId() != p.id {
|
|
glog.V(logger.Debug).Infof("Received hashes from incorrect peer(%s)", packet.PeerId())
|
|
break
|
|
}
|
|
hashReqTimer.UpdateSince(request)
|
|
timeout.Stop()
|
|
|
|
// If no more hashes are inbound, notify the block fetcher and return
|
|
if packet.Items() == 0 {
|
|
glog.V(logger.Debug).Infof("%v: no available hashes", p)
|
|
|
|
select {
|
|
case d.blockWakeCh <- false:
|
|
case <-d.cancelCh:
|
|
}
|
|
// If no hashes were retrieved at all, the peer violated it's TD promise that it had a
|
|
// better chain compared to ours. The only exception is if it's promised blocks were
|
|
// already imported by other means (e.g. fecher):
|
|
//
|
|
// R <remote peer>, L <local node>: Both at block 10
|
|
// R: Mine block 11, and propagate it to L
|
|
// L: Queue block 11 for import
|
|
// L: Notice that R's head and TD increased compared to ours, start sync
|
|
// L: Import of block 11 finishes
|
|
// L: Sync begins, and finds common ancestor at 11
|
|
// L: Request new hashes up from 11 (R's TD was higher, it must have something)
|
|
// R: Nothing to give
|
|
if !gotHashes && td.Cmp(d.getTd(d.headBlock().Hash())) > 0 {
|
|
return errStallingPeer
|
|
}
|
|
return nil
|
|
}
|
|
gotHashes = true
|
|
hashes := packet.(*hashPack).hashes
|
|
|
|
// Otherwise insert all the new hashes, aborting in case of junk
|
|
glog.V(logger.Detail).Infof("%v: scheduling %d hashes from #%d", p, len(hashes), from)
|
|
|
|
inserts := d.queue.Schedule61(hashes, true)
|
|
if len(inserts) != len(hashes) {
|
|
glog.V(logger.Debug).Infof("%v: stale hashes", p)
|
|
return errBadPeer
|
|
}
|
|
// Notify the block fetcher of new hashes, but stop if queue is full
|
|
if d.queue.PendingBlocks() < maxQueuedHashes {
|
|
// We still have hashes to fetch, send continuation wake signal (potential)
|
|
select {
|
|
case d.blockWakeCh <- true:
|
|
default:
|
|
}
|
|
} else {
|
|
// Hash limit reached, send a termination wake signal (enforced)
|
|
select {
|
|
case d.blockWakeCh <- false:
|
|
case <-d.cancelCh:
|
|
}
|
|
return nil
|
|
}
|
|
// Queue not yet full, fetch the next batch
|
|
from += uint64(len(hashes))
|
|
getHashes(from)
|
|
|
|
case <-timeout.C:
|
|
glog.V(logger.Debug).Infof("%v: hash request timed out", p)
|
|
hashTimeoutMeter.Mark(1)
|
|
return errTimeout
|
|
}
|
|
}
|
|
}
|
|
|
|
// fetchBlocks61 iteratively downloads the scheduled hashes, taking any available
|
|
// peers, reserving a chunk of blocks for each, waiting for delivery and also
|
|
// periodically checking for timeouts.
|
|
func (d *Downloader) fetchBlocks61(from uint64) error {
|
|
glog.V(logger.Debug).Infof("Downloading blocks from #%d", from)
|
|
defer glog.V(logger.Debug).Infof("Block download terminated")
|
|
|
|
// Create a timeout timer for scheduling expiration tasks
|
|
ticker := time.NewTicker(100 * time.Millisecond)
|
|
defer ticker.Stop()
|
|
|
|
update := make(chan struct{}, 1)
|
|
|
|
// Fetch blocks until the hash fetcher's done
|
|
finished := false
|
|
for {
|
|
select {
|
|
case <-d.cancelCh:
|
|
return errCancelBlockFetch
|
|
|
|
case <-d.headerCh:
|
|
// Out of bounds eth/62 block headers received, ignore them
|
|
|
|
case <-d.bodyCh:
|
|
// Out of bounds eth/62 block bodies received, ignore them
|
|
|
|
case packet := <-d.blockCh:
|
|
// If the peer was previously banned and failed to deliver it's pack
|
|
// in a reasonable time frame, ignore it's message.
|
|
if peer := d.peers.Peer(packet.PeerId()); peer != nil {
|
|
// Deliver the received chunk of blocks, and demote in case of errors
|
|
blocks := packet.(*blockPack).blocks
|
|
err := d.queue.DeliverBlocks(peer.id, blocks)
|
|
switch err {
|
|
case nil:
|
|
// If no blocks were delivered, demote the peer (need the delivery above)
|
|
if len(blocks) == 0 {
|
|
peer.Demote()
|
|
peer.SetBlocksIdle()
|
|
glog.V(logger.Detail).Infof("%s: no blocks delivered", peer)
|
|
break
|
|
}
|
|
// All was successful, promote the peer and potentially start processing
|
|
peer.Promote()
|
|
peer.SetBlocksIdle()
|
|
glog.V(logger.Detail).Infof("%s: delivered %d blocks", peer, len(blocks))
|
|
go d.process()
|
|
|
|
case errInvalidChain:
|
|
// The hash chain is invalid (blocks are not ordered properly), abort
|
|
return err
|
|
|
|
case errNoFetchesPending:
|
|
// Peer probably timed out with its delivery but came through
|
|
// in the end, demote, but allow to to pull from this peer.
|
|
peer.Demote()
|
|
peer.SetBlocksIdle()
|
|
glog.V(logger.Detail).Infof("%s: out of bound delivery", peer)
|
|
|
|
case errStaleDelivery:
|
|
// Delivered something completely else than requested, usually
|
|
// caused by a timeout and delivery during a new sync cycle.
|
|
// Don't set it to idle as the original request should still be
|
|
// in flight.
|
|
peer.Demote()
|
|
glog.V(logger.Detail).Infof("%s: stale delivery", peer)
|
|
|
|
default:
|
|
// Peer did something semi-useful, demote but keep it around
|
|
peer.Demote()
|
|
peer.SetBlocksIdle()
|
|
glog.V(logger.Detail).Infof("%s: delivery partially failed: %v", peer, err)
|
|
go d.process()
|
|
}
|
|
}
|
|
// Blocks arrived, try to update the progress
|
|
select {
|
|
case update <- struct{}{}:
|
|
default:
|
|
}
|
|
|
|
case cont := <-d.blockWakeCh:
|
|
// The hash fetcher sent a continuation flag, check if it's done
|
|
if !cont {
|
|
finished = true
|
|
}
|
|
// Hashes arrive, try to update the progress
|
|
select {
|
|
case update <- struct{}{}:
|
|
default:
|
|
}
|
|
|
|
case <-ticker.C:
|
|
// Sanity check update the progress
|
|
select {
|
|
case update <- struct{}{}:
|
|
default:
|
|
}
|
|
|
|
case <-update:
|
|
// Short circuit if we lost all our peers
|
|
if d.peers.Len() == 0 {
|
|
return errNoPeers
|
|
}
|
|
// Check for block request timeouts and demote the responsible peers
|
|
for _, pid := range d.queue.ExpireBlocks(blockHardTTL) {
|
|
if peer := d.peers.Peer(pid); peer != nil {
|
|
peer.Demote()
|
|
glog.V(logger.Detail).Infof("%s: block delivery timeout", peer)
|
|
}
|
|
}
|
|
// If there's nothing more to fetch, wait or terminate
|
|
if d.queue.PendingBlocks() == 0 {
|
|
if !d.queue.InFlightBlocks() && finished {
|
|
glog.V(logger.Debug).Infof("Block fetching completed")
|
|
return nil
|
|
}
|
|
break
|
|
}
|
|
// Send a download request to all idle peers, until throttled
|
|
throttled := false
|
|
idles, total := d.peers.BlockIdlePeers()
|
|
|
|
for _, peer := range idles {
|
|
// Short circuit if throttling activated
|
|
if d.queue.ThrottleBlocks() {
|
|
throttled = true
|
|
break
|
|
}
|
|
// Reserve a chunk of hashes for a peer. A nil can mean either that
|
|
// no more hashes are available, or that the peer is known not to
|
|
// have them.
|
|
request := d.queue.ReserveBlocks(peer, peer.BlockCapacity())
|
|
if request == nil {
|
|
continue
|
|
}
|
|
if glog.V(logger.Detail) {
|
|
glog.Infof("%s: requesting %d blocks", peer, len(request.Hashes))
|
|
}
|
|
// Fetch the chunk and make sure any errors return the hashes to the queue
|
|
if err := peer.Fetch61(request); err != nil {
|
|
glog.V(logger.Error).Infof("%v: fetch failed, rescheduling", peer)
|
|
d.queue.CancelBlocks(request)
|
|
}
|
|
}
|
|
// Make sure that we have peers available for fetching. If all peers have been tried
|
|
// and all failed throw an error
|
|
if !throttled && !d.queue.InFlightBlocks() && len(idles) == total {
|
|
return errPeersUnavailable
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// fetchHeight retrieves the head header of the remote peer to aid in estimating
|
|
// the total time a pending synchronisation would take.
|
|
func (d *Downloader) fetchHeight(p *peer) (uint64, error) {
|
|
glog.V(logger.Debug).Infof("%v: retrieving remote chain height", p)
|
|
|
|
// Request the advertised remote head block and wait for the response
|
|
go p.getRelHeaders(p.head, 1, 0, false)
|
|
|
|
timeout := time.After(headerTTL)
|
|
for {
|
|
select {
|
|
case <-d.cancelCh:
|
|
return 0, errCancelBlockFetch
|
|
|
|
case packet := <-d.headerCh:
|
|
// Discard anything not from the origin peer
|
|
if packet.PeerId() != p.id {
|
|
glog.V(logger.Debug).Infof("Received headers from incorrect peer(%s)", packet.PeerId())
|
|
break
|
|
}
|
|
// Make sure the peer actually gave something valid
|
|
headers := packet.(*headerPack).headers
|
|
if len(headers) != 1 {
|
|
glog.V(logger.Debug).Infof("%v: invalid number of head headers: %d != 1", p, len(headers))
|
|
return 0, errBadPeer
|
|
}
|
|
return headers[0].Number.Uint64(), nil
|
|
|
|
case <-d.bodyCh:
|
|
// Out of bounds block bodies received, ignore them
|
|
|
|
case <-d.hashCh:
|
|
// Out of bounds eth/61 hashes received, ignore them
|
|
|
|
case <-d.blockCh:
|
|
// Out of bounds eth/61 blocks received, ignore them
|
|
|
|
case <-timeout:
|
|
glog.V(logger.Debug).Infof("%v: head header timeout", p)
|
|
return 0, errTimeout
|
|
}
|
|
}
|
|
}
|
|
|
|
// findAncestor tries to locate the common ancestor link of the local chain and
|
|
// a remote peers blockchain. In the general case when our node was in sync and
|
|
// on the correct chain, checking the top N links should already get us a match.
|
|
// In the rare scenario when we ended up on a long reorganization (i.e. none of
|
|
// the head links match), we do a binary search to find the common ancestor.
|
|
func (d *Downloader) findAncestor(p *peer) (uint64, error) {
|
|
glog.V(logger.Debug).Infof("%v: looking for common ancestor", p)
|
|
|
|
// Request our head headers to short circuit ancestor location
|
|
head := d.headHeader().Number.Uint64()
|
|
if d.mode == FullSync {
|
|
head = d.headBlock().NumberU64()
|
|
} else if d.mode == FastSync {
|
|
head = d.headFastBlock().NumberU64()
|
|
}
|
|
from := int64(head) - int64(MaxHeaderFetch) + 1
|
|
if from < 0 {
|
|
from = 0
|
|
}
|
|
go p.getAbsHeaders(uint64(from), MaxHeaderFetch, 0, false)
|
|
|
|
// Wait for the remote response to the head fetch
|
|
number, hash := uint64(0), common.Hash{}
|
|
timeout := time.After(hashTTL)
|
|
|
|
for finished := false; !finished; {
|
|
select {
|
|
case <-d.cancelCh:
|
|
return 0, errCancelHashFetch
|
|
|
|
case packet := <-d.headerCh:
|
|
// Discard anything not from the origin peer
|
|
if packet.PeerId() != p.id {
|
|
glog.V(logger.Debug).Infof("Received headers from incorrect peer(%s)", packet.PeerId())
|
|
break
|
|
}
|
|
// Make sure the peer actually gave something valid
|
|
headers := packet.(*headerPack).headers
|
|
if len(headers) == 0 {
|
|
glog.V(logger.Debug).Infof("%v: empty head header set", p)
|
|
return 0, errEmptyHeaderSet
|
|
}
|
|
// Check if a common ancestor was found
|
|
finished = true
|
|
for i := len(headers) - 1; i >= 0; i-- {
|
|
if (d.mode != LightSync && d.hasBlock(headers[i].Hash())) || (d.mode == LightSync && d.hasHeader(headers[i].Hash())) {
|
|
number, hash = headers[i].Number.Uint64(), headers[i].Hash()
|
|
break
|
|
}
|
|
}
|
|
|
|
case <-d.bodyCh:
|
|
// Out of bounds block bodies received, ignore them
|
|
|
|
case <-d.hashCh:
|
|
// Out of bounds eth/61 hashes received, ignore them
|
|
|
|
case <-d.blockCh:
|
|
// Out of bounds eth/61 blocks received, ignore them
|
|
|
|
case <-timeout:
|
|
glog.V(logger.Debug).Infof("%v: head header timeout", p)
|
|
return 0, errTimeout
|
|
}
|
|
}
|
|
// If the head fetch already found an ancestor, return
|
|
if !common.EmptyHash(hash) {
|
|
glog.V(logger.Debug).Infof("%v: common ancestor: #%d [%x…]", p, number, hash[:4])
|
|
return number, nil
|
|
}
|
|
// Ancestor not found, we need to binary search over our chain
|
|
start, end := uint64(0), head
|
|
for start+1 < end {
|
|
// Split our chain interval in two, and request the hash to cross check
|
|
check := (start + end) / 2
|
|
|
|
timeout := time.After(hashTTL)
|
|
go p.getAbsHeaders(uint64(check), 1, 0, false)
|
|
|
|
// Wait until a reply arrives to this request
|
|
for arrived := false; !arrived; {
|
|
select {
|
|
case <-d.cancelCh:
|
|
return 0, errCancelHashFetch
|
|
|
|
case packer := <-d.headerCh:
|
|
// Discard anything not from the origin peer
|
|
if packer.PeerId() != p.id {
|
|
glog.V(logger.Debug).Infof("Received headers from incorrect peer(%s)", packer.PeerId())
|
|
break
|
|
}
|
|
// Make sure the peer actually gave something valid
|
|
headers := packer.(*headerPack).headers
|
|
if len(headers) != 1 {
|
|
glog.V(logger.Debug).Infof("%v: invalid search header set (%d)", p, len(headers))
|
|
return 0, errBadPeer
|
|
}
|
|
arrived = true
|
|
|
|
// Modify the search interval based on the response
|
|
if (d.mode == FullSync && !d.hasBlock(headers[0].Hash())) || (d.mode != FullSync && !d.hasHeader(headers[0].Hash())) {
|
|
end = check
|
|
break
|
|
}
|
|
header := d.getHeader(headers[0].Hash()) // Independent of sync mode, header surely exists
|
|
if header.Number.Uint64() != check {
|
|
glog.V(logger.Debug).Infof("%v: non requested header #%d [%x…], instead of #%d", p, header.Number, header.Hash().Bytes()[:4], check)
|
|
return 0, errBadPeer
|
|
}
|
|
start = check
|
|
|
|
case <-d.bodyCh:
|
|
// Out of bounds block bodies received, ignore them
|
|
|
|
case <-d.hashCh:
|
|
// Out of bounds eth/61 hashes received, ignore them
|
|
|
|
case <-d.blockCh:
|
|
// Out of bounds eth/61 blocks received, ignore them
|
|
|
|
case <-timeout:
|
|
glog.V(logger.Debug).Infof("%v: search header timeout", p)
|
|
return 0, errTimeout
|
|
}
|
|
}
|
|
}
|
|
return start, nil
|
|
}
|
|
|
|
// fetchHeaders keeps retrieving headers from the requested number, until no more
|
|
// are returned, potentially throttling on the way.
|
|
//
|
|
// The queue parameter can be used to switch between queuing headers for block
|
|
// body download too, or directly import as pure header chains.
|
|
func (d *Downloader) fetchHeaders(p *peer, td *big.Int, from, latest uint64) error {
|
|
glog.V(logger.Debug).Infof("%v: downloading headers from #%d", p, from)
|
|
defer glog.V(logger.Debug).Infof("%v: header download terminated", p)
|
|
|
|
// Keep a count of uncertain headers to roll back
|
|
rollback := []*types.Header{}
|
|
defer func() {
|
|
if len(rollback) > 0 {
|
|
hashes := make([]common.Hash, len(rollback))
|
|
for i, header := range rollback {
|
|
hashes[i] = header.Hash()
|
|
}
|
|
d.rollback(hashes)
|
|
}
|
|
}()
|
|
// Calculate the pivoting point for switching from fast to slow sync
|
|
pivot := uint64(0)
|
|
if d.mode == FastSync && latest > uint64(minFullBlocks) {
|
|
pivot = latest - uint64(minFullBlocks)
|
|
} else if d.mode == LightSync {
|
|
pivot = latest
|
|
}
|
|
// Create a timeout timer, and the associated hash fetcher
|
|
request := time.Now() // time of the last fetch request
|
|
timeout := time.NewTimer(0) // timer to dump a non-responsive active peer
|
|
<-timeout.C // timeout channel should be initially empty
|
|
defer timeout.Stop()
|
|
|
|
getHeaders := func(from uint64) {
|
|
glog.V(logger.Detail).Infof("%v: fetching %d headers from #%d", p, MaxHeaderFetch, from)
|
|
|
|
go p.getAbsHeaders(from, MaxHeaderFetch, 0, false)
|
|
request = time.Now()
|
|
timeout.Reset(headerTTL)
|
|
}
|
|
// Start pulling headers, until all are exhausted
|
|
getHeaders(from)
|
|
gotHeaders := false
|
|
|
|
for {
|
|
select {
|
|
case <-d.cancelCh:
|
|
return errCancelHeaderFetch
|
|
|
|
case <-d.hashCh:
|
|
// Out of bounds eth/61 hashes received, ignore them
|
|
|
|
case <-d.blockCh:
|
|
// Out of bounds eth/61 blocks received, ignore them
|
|
|
|
case packet := <-d.headerCh:
|
|
// Make sure the active peer is giving us the headers
|
|
if packet.PeerId() != p.id {
|
|
glog.V(logger.Debug).Infof("Received headers from incorrect peer (%s)", packet.PeerId())
|
|
break
|
|
}
|
|
headerReqTimer.UpdateSince(request)
|
|
timeout.Stop()
|
|
|
|
// If no more headers are inbound, notify the content fetchers and return
|
|
if packet.Items() == 0 {
|
|
glog.V(logger.Debug).Infof("%v: no available headers", p)
|
|
|
|
for _, ch := range []chan bool{d.bodyWakeCh, d.receiptWakeCh, d.stateWakeCh} {
|
|
select {
|
|
case ch <- false:
|
|
case <-d.cancelCh:
|
|
}
|
|
}
|
|
// If no headers were retrieved at all, the peer violated it's TD promise that it had a
|
|
// better chain compared to ours. The only exception is if it's promised blocks were
|
|
// already imported by other means (e.g. fecher):
|
|
//
|
|
// R <remote peer>, L <local node>: Both at block 10
|
|
// R: Mine block 11, and propagate it to L
|
|
// L: Queue block 11 for import
|
|
// L: Notice that R's head and TD increased compared to ours, start sync
|
|
// L: Import of block 11 finishes
|
|
// L: Sync begins, and finds common ancestor at 11
|
|
// L: Request new headers up from 11 (R's TD was higher, it must have something)
|
|
// R: Nothing to give
|
|
if !gotHeaders && td.Cmp(d.getTd(d.headBlock().Hash())) > 0 {
|
|
return errStallingPeer
|
|
}
|
|
return nil
|
|
}
|
|
gotHeaders = true
|
|
headers := packet.(*headerPack).headers
|
|
|
|
// Otherwise insert all the new headers, aborting in case of junk
|
|
glog.V(logger.Detail).Infof("%v: schedule %d headers from #%d", p, len(headers), from)
|
|
|
|
if d.mode == FastSync || d.mode == LightSync {
|
|
// Collect the yet unknown headers to mark them as uncertain
|
|
unknown := make([]*types.Header, 0, len(headers))
|
|
for _, header := range headers {
|
|
if !d.hasHeader(header.Hash()) {
|
|
unknown = append(unknown, header)
|
|
}
|
|
}
|
|
// If we're importing pure headers, verify based on their recentness
|
|
frequency := headerCheckFrequency
|
|
if headers[len(headers)-1].Number.Uint64()+uint64(minCheckedHeaders) > pivot {
|
|
frequency = 1
|
|
}
|
|
if n, err := d.insertHeaders(headers, frequency); err != nil {
|
|
glog.V(logger.Debug).Infof("%v: invalid header #%d [%x…]: %v", p, headers[n].Number, headers[n].Hash().Bytes()[:4], err)
|
|
return errInvalidChain
|
|
}
|
|
// All verifications passed, store newly found uncertain headers
|
|
rollback = append(rollback, unknown...)
|
|
if len(rollback) > minCheckedHeaders {
|
|
rollback = append(rollback[:0], rollback[len(rollback)-minCheckedHeaders:]...)
|
|
}
|
|
if headers[len(headers)-1].Number.Uint64() >= pivot {
|
|
rollback = rollback[:0]
|
|
}
|
|
}
|
|
if d.mode == FullSync || d.mode == FastSync {
|
|
inserts := d.queue.Schedule(headers, from)
|
|
if len(inserts) != len(headers) {
|
|
glog.V(logger.Debug).Infof("%v: stale headers", p)
|
|
return errBadPeer
|
|
}
|
|
}
|
|
// Notify the content fetchers of new headers, but stop if queue is full
|
|
cont := d.queue.PendingBlocks() < maxQueuedHeaders || d.queue.PendingReceipts() < maxQueuedHeaders
|
|
for _, ch := range []chan bool{d.bodyWakeCh, d.receiptWakeCh, d.stateWakeCh} {
|
|
if cont {
|
|
// We still have headers to fetch, send continuation wake signal (potential)
|
|
select {
|
|
case ch <- true:
|
|
default:
|
|
}
|
|
} else {
|
|
// Header limit reached, send a termination wake signal (enforced)
|
|
select {
|
|
case ch <- false:
|
|
case <-d.cancelCh:
|
|
}
|
|
return nil
|
|
}
|
|
}
|
|
// Queue not yet full, fetch the next batch
|
|
from += uint64(len(headers))
|
|
getHeaders(from)
|
|
|
|
case <-timeout.C:
|
|
// Header retrieval timed out, consider the peer bad and drop
|
|
glog.V(logger.Debug).Infof("%v: header request timed out", p)
|
|
headerTimeoutMeter.Mark(1)
|
|
d.dropPeer(p.id)
|
|
|
|
// Finish the sync gracefully instead of dumping the gathered data though
|
|
for _, ch := range []chan bool{d.bodyWakeCh, d.receiptWakeCh, d.stateWakeCh} {
|
|
select {
|
|
case ch <- false:
|
|
case <-d.cancelCh:
|
|
}
|
|
}
|
|
return nil
|
|
}
|
|
}
|
|
}
|
|
|
|
// fetchBodies iteratively downloads the scheduled block bodies, taking any
|
|
// available peers, reserving a chunk of blocks for each, waiting for delivery
|
|
// and also periodically checking for timeouts.
|
|
func (d *Downloader) fetchBodies(from uint64) error {
|
|
glog.V(logger.Debug).Infof("Downloading block bodies from #%d", from)
|
|
|
|
var (
|
|
deliver = func(packet dataPack) error {
|
|
pack := packet.(*bodyPack)
|
|
return d.queue.DeliverBodies(pack.peerId, pack.transactions, pack.uncles)
|
|
}
|
|
expire = func() []string { return d.queue.ExpireBodies(bodyHardTTL) }
|
|
fetch = func(p *peer, req *fetchRequest) error { return p.FetchBodies(req) }
|
|
capacity = func(p *peer) int { return p.BlockCapacity() }
|
|
getIdles = func() ([]*peer, int) { return d.peers.BodyIdlePeers() }
|
|
setIdle = func(p *peer) { p.SetBlocksIdle() }
|
|
)
|
|
err := d.fetchParts(errCancelBodyFetch, d.bodyCh, deliver, d.bodyWakeCh, expire,
|
|
d.queue.PendingBlocks, d.queue.InFlightBlocks, d.queue.ThrottleBlocks, d.queue.ReserveBodies,
|
|
d.bodyFetchHook, fetch, d.queue.CancelBodies, capacity, getIdles, setIdle, "Body")
|
|
|
|
glog.V(logger.Debug).Infof("Block body download terminated: %v", err)
|
|
return err
|
|
}
|
|
|
|
// fetchReceipts iteratively downloads the scheduled block receipts, taking any
|
|
// available peers, reserving a chunk of receipts for each, waiting for delivery
|
|
// and also periodically checking for timeouts.
|
|
func (d *Downloader) fetchReceipts(from uint64) error {
|
|
glog.V(logger.Debug).Infof("Downloading receipts from #%d", from)
|
|
|
|
var (
|
|
deliver = func(packet dataPack) error {
|
|
pack := packet.(*receiptPack)
|
|
return d.queue.DeliverReceipts(pack.peerId, pack.receipts)
|
|
}
|
|
expire = func() []string { return d.queue.ExpireReceipts(bodyHardTTL) }
|
|
fetch = func(p *peer, req *fetchRequest) error { return p.FetchReceipts(req) }
|
|
capacity = func(p *peer) int { return p.ReceiptCapacity() }
|
|
setIdle = func(p *peer) { p.SetReceiptsIdle() }
|
|
)
|
|
err := d.fetchParts(errCancelReceiptFetch, d.receiptCh, deliver, d.receiptWakeCh, expire,
|
|
d.queue.PendingReceipts, d.queue.InFlightReceipts, d.queue.ThrottleReceipts, d.queue.ReserveReceipts,
|
|
d.receiptFetchHook, fetch, d.queue.CancelReceipts, capacity, d.peers.ReceiptIdlePeers, setIdle, "Receipt")
|
|
|
|
glog.V(logger.Debug).Infof("Receipt download terminated: %v", err)
|
|
return err
|
|
}
|
|
|
|
// fetchNodeData iteratively downloads the scheduled state trie nodes, taking any
|
|
// available peers, reserving a chunk of nodes for each, waiting for delivery and
|
|
// also periodically checking for timeouts.
|
|
func (d *Downloader) fetchNodeData() error {
|
|
glog.V(logger.Debug).Infof("Downloading node state data")
|
|
|
|
var (
|
|
deliver = func(packet dataPack) error {
|
|
start := time.Now()
|
|
return d.queue.DeliverNodeData(packet.PeerId(), packet.(*statePack).states, func(err error, delivered int) {
|
|
if err != nil {
|
|
// If the node data processing failed, the root hash is very wrong, abort
|
|
glog.V(logger.Error).Infof("peer %d: state processing failed: %v", packet.PeerId(), err)
|
|
d.cancel()
|
|
return
|
|
}
|
|
// Processing succeeded, notify state fetcher and processor of continuation
|
|
if d.queue.PendingNodeData() == 0 {
|
|
go d.process()
|
|
} else {
|
|
select {
|
|
case d.stateWakeCh <- true:
|
|
default:
|
|
}
|
|
}
|
|
// Log a message to the user and return
|
|
d.syncStatsLock.Lock()
|
|
defer d.syncStatsLock.Unlock()
|
|
|
|
d.syncStatsStateDone += uint64(delivered)
|
|
glog.V(logger.Info).Infof("imported %d state entries in %v: processed %d in total", delivered, time.Since(start), d.syncStatsStateDone)
|
|
})
|
|
}
|
|
expire = func() []string { return d.queue.ExpireNodeData(stateHardTTL) }
|
|
throttle = func() bool { return false }
|
|
reserve = func(p *peer, count int) (*fetchRequest, bool, error) {
|
|
return d.queue.ReserveNodeData(p, count), false, nil
|
|
}
|
|
fetch = func(p *peer, req *fetchRequest) error { return p.FetchNodeData(req) }
|
|
capacity = func(p *peer) int { return p.NodeDataCapacity() }
|
|
setIdle = func(p *peer) { p.SetNodeDataIdle() }
|
|
)
|
|
err := d.fetchParts(errCancelReceiptFetch, d.stateCh, deliver, d.stateWakeCh, expire,
|
|
d.queue.PendingNodeData, d.queue.InFlightNodeData, throttle, reserve, nil, fetch,
|
|
d.queue.CancelNodeData, capacity, d.peers.ReceiptIdlePeers, setIdle, "State")
|
|
|
|
glog.V(logger.Debug).Infof("Node state data download terminated: %v", err)
|
|
return err
|
|
}
|
|
|
|
// fetchParts iteratively downloads scheduled block parts, taking any available
|
|
// peers, reserving a chunk of fetch requests for each, waiting for delivery and
|
|
// also periodically checking for timeouts.
|
|
func (d *Downloader) fetchParts(errCancel error, deliveryCh chan dataPack, deliver func(packet dataPack) error, wakeCh chan bool,
|
|
expire func() []string, pending func() int, inFlight func() bool, throttle func() bool, reserve func(*peer, int) (*fetchRequest, bool, error),
|
|
fetchHook func([]*types.Header), fetch func(*peer, *fetchRequest) error, cancel func(*fetchRequest), capacity func(*peer) int,
|
|
idle func() ([]*peer, int), setIdle func(*peer), kind string) error {
|
|
|
|
// Create a ticker to detect expired retreival tasks
|
|
ticker := time.NewTicker(100 * time.Millisecond)
|
|
defer ticker.Stop()
|
|
|
|
update := make(chan struct{}, 1)
|
|
|
|
// Prepare the queue and fetch block parts until the block header fetcher's done
|
|
finished := false
|
|
for {
|
|
select {
|
|
case <-d.cancelCh:
|
|
return errCancel
|
|
|
|
case <-d.hashCh:
|
|
// Out of bounds eth/61 hashes received, ignore them
|
|
|
|
case <-d.blockCh:
|
|
// Out of bounds eth/61 blocks received, ignore them
|
|
|
|
case packet := <-deliveryCh:
|
|
// If the peer was previously banned and failed to deliver it's pack
|
|
// in a reasonable time frame, ignore it's message.
|
|
if peer := d.peers.Peer(packet.PeerId()); peer != nil {
|
|
// Deliver the received chunk of data, and demote in case of errors
|
|
switch err := deliver(packet); err {
|
|
case nil:
|
|
// If no blocks were delivered, demote the peer (need the delivery above to clean internal queue!)
|
|
if packet.Items() == 0 {
|
|
peer.Demote()
|
|
setIdle(peer)
|
|
glog.V(logger.Detail).Infof("%s: no %s delivered", peer, strings.ToLower(kind))
|
|
break
|
|
}
|
|
// All was successful, promote the peer and potentially start processing
|
|
peer.Promote()
|
|
setIdle(peer)
|
|
glog.V(logger.Detail).Infof("%s: delivered %s %s(s)", peer, packet.Stats(), strings.ToLower(kind))
|
|
go d.process()
|
|
|
|
case errInvalidChain:
|
|
// The hash chain is invalid (blocks are not ordered properly), abort
|
|
return err
|
|
|
|
case errInvalidBody, errInvalidReceipt:
|
|
// The peer delivered something very bad, drop immediately
|
|
glog.V(logger.Error).Infof("%s: delivered invalid %s, dropping", peer, strings.ToLower(kind))
|
|
d.dropPeer(peer.id)
|
|
|
|
case errNoFetchesPending:
|
|
// Peer probably timed out with its delivery but came through
|
|
// in the end, demote, but allow to to pull from this peer.
|
|
peer.Demote()
|
|
setIdle(peer)
|
|
glog.V(logger.Detail).Infof("%s: out of bound %s delivery", peer, strings.ToLower(kind))
|
|
|
|
case errStaleDelivery:
|
|
// Delivered something completely else than requested, usually
|
|
// caused by a timeout and delivery during a new sync cycle.
|
|
// Don't set it to idle as the original request should still be
|
|
// in flight.
|
|
peer.Demote()
|
|
glog.V(logger.Detail).Infof("%s: %s stale delivery", peer, strings.ToLower(kind))
|
|
|
|
default:
|
|
// Peer did something semi-useful, demote but keep it around
|
|
peer.Demote()
|
|
setIdle(peer)
|
|
glog.V(logger.Detail).Infof("%s: %s delivery partially failed: %v", peer, strings.ToLower(kind), err)
|
|
go d.process()
|
|
}
|
|
}
|
|
// Blocks assembled, try to update the progress
|
|
select {
|
|
case update <- struct{}{}:
|
|
default:
|
|
}
|
|
|
|
case cont := <-wakeCh:
|
|
// The header fetcher sent a continuation flag, check if it's done
|
|
if !cont {
|
|
finished = true
|
|
}
|
|
// Headers arrive, try to update the progress
|
|
select {
|
|
case update <- struct{}{}:
|
|
default:
|
|
}
|
|
|
|
case <-ticker.C:
|
|
// Sanity check update the progress
|
|
select {
|
|
case update <- struct{}{}:
|
|
default:
|
|
}
|
|
|
|
case <-update:
|
|
// Short circuit if we lost all our peers
|
|
if d.peers.Len() == 0 {
|
|
return errNoPeers
|
|
}
|
|
// Check for fetch request timeouts and demote the responsible peers
|
|
for _, pid := range expire() {
|
|
if peer := d.peers.Peer(pid); peer != nil {
|
|
peer.Demote()
|
|
setIdle(peer)
|
|
glog.V(logger.Detail).Infof("%s: %s delivery timeout", peer, strings.ToLower(kind))
|
|
}
|
|
}
|
|
// If there's nothing more to fetch, wait or terminate
|
|
if pending() == 0 {
|
|
if !inFlight() && finished {
|
|
glog.V(logger.Debug).Infof("%s fetching completed", kind)
|
|
return nil
|
|
}
|
|
break
|
|
}
|
|
// Send a download request to all idle peers, until throttled
|
|
progressed, throttled, running := false, false, inFlight()
|
|
idles, total := idle()
|
|
|
|
for _, peer := range idles {
|
|
// Short circuit if throttling activated
|
|
if throttle() {
|
|
throttled = true
|
|
break
|
|
}
|
|
// Reserve a chunk of fetches for a peer. A nil can mean either that
|
|
// no more headers are available, or that the peer is known not to
|
|
// have them.
|
|
request, progress, err := reserve(peer, capacity(peer))
|
|
if err != nil {
|
|
return err
|
|
}
|
|
if progress {
|
|
progressed = true
|
|
go d.process()
|
|
}
|
|
if request == nil {
|
|
continue
|
|
}
|
|
if glog.V(logger.Detail) {
|
|
if len(request.Headers) > 0 {
|
|
glog.Infof("%s: requesting %d %s(s), first at #%d", peer, len(request.Headers), strings.ToLower(kind), request.Headers[0].Number)
|
|
} else {
|
|
glog.Infof("%s: requesting %d %s(s)", peer, len(request.Hashes), strings.ToLower(kind))
|
|
}
|
|
}
|
|
// Fetch the chunk and make sure any errors return the hashes to the queue
|
|
if fetchHook != nil {
|
|
fetchHook(request.Headers)
|
|
}
|
|
if err := fetch(peer, request); err != nil {
|
|
glog.V(logger.Error).Infof("%v: %s fetch failed, rescheduling", peer, strings.ToLower(kind))
|
|
cancel(request)
|
|
}
|
|
running = true
|
|
}
|
|
// Make sure that we have peers available for fetching. If all peers have been tried
|
|
// and all failed throw an error
|
|
if !progressed && !throttled && !running && len(idles) == total && pending() > 0 {
|
|
return errPeersUnavailable
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// process takes fetch results from the queue and tries to import them into the
|
|
// chain. The type of import operation will depend on the result contents:
|
|
// -
|
|
//
|
|
// The algorithmic flow is as follows:
|
|
// - The `processing` flag is swapped to 1 to ensure singleton access
|
|
// - The current `cancel` channel is retrieved to detect sync abortions
|
|
// - Blocks are iteratively taken from the cache and inserted into the chain
|
|
// - When the cache becomes empty, insertion stops
|
|
// - The `processing` flag is swapped back to 0
|
|
// - A post-exit check is made whether new blocks became available
|
|
// - This step is important: it handles a potential race condition between
|
|
// checking for no more work, and releasing the processing "mutex". In
|
|
// between these state changes, a block may have arrived, but a processing
|
|
// attempt denied, so we need to re-enter to ensure the block isn't left
|
|
// to idle in the cache.
|
|
func (d *Downloader) process() {
|
|
// Make sure only one goroutine is ever allowed to process blocks at once
|
|
if !atomic.CompareAndSwapInt32(&d.processing, 0, 1) {
|
|
return
|
|
}
|
|
// If the processor just exited, but there are freshly pending items, try to
|
|
// reenter. This is needed because the goroutine spinned up for processing
|
|
// the fresh results might have been rejected entry to to this present thread
|
|
// not yet releasing the `processing` state.
|
|
defer func() {
|
|
if atomic.LoadInt32(&d.interrupt) == 0 && d.queue.GetHeadResult() != nil {
|
|
d.process()
|
|
}
|
|
}()
|
|
// Release the lock upon exit (note, before checking for reentry!)
|
|
// the import statistics to zero.
|
|
defer atomic.StoreInt32(&d.processing, 0)
|
|
|
|
// Repeat the processing as long as there are results to process
|
|
for {
|
|
// Fetch the next batch of results
|
|
results := d.queue.TakeResults()
|
|
if len(results) == 0 {
|
|
return
|
|
}
|
|
if d.chainInsertHook != nil {
|
|
d.chainInsertHook(results)
|
|
}
|
|
// Actually import the blocks
|
|
if glog.V(logger.Debug) {
|
|
first, last := results[0].Header, results[len(results)-1].Header
|
|
glog.Infof("Inserting chain with %d items (#%d [%x…] - #%d [%x…])", len(results), first.Number, first.Hash().Bytes()[:4], last.Number, last.Hash().Bytes()[:4])
|
|
}
|
|
for len(results) != 0 {
|
|
// Check for any termination requests
|
|
if atomic.LoadInt32(&d.interrupt) == 1 {
|
|
return
|
|
}
|
|
// Retrieve the a batch of results to import
|
|
var (
|
|
headers = make([]*types.Header, 0, maxResultsProcess)
|
|
blocks = make([]*types.Block, 0, maxResultsProcess)
|
|
receipts = make([]types.Receipts, 0, maxResultsProcess)
|
|
)
|
|
items := int(math.Min(float64(len(results)), float64(maxResultsProcess)))
|
|
for _, result := range results[:items] {
|
|
switch {
|
|
case d.mode == FullSync:
|
|
blocks = append(blocks, types.NewBlockWithHeader(result.Header).WithBody(result.Transactions, result.Uncles))
|
|
case d.mode == FastSync:
|
|
blocks = append(blocks, types.NewBlockWithHeader(result.Header).WithBody(result.Transactions, result.Uncles))
|
|
if result.Header.Number.Uint64() <= d.queue.fastSyncPivot {
|
|
receipts = append(receipts, result.Receipts)
|
|
}
|
|
case d.mode == LightSync:
|
|
headers = append(headers, result.Header)
|
|
}
|
|
}
|
|
// Try to process the results, aborting if there's an error
|
|
var (
|
|
err error
|
|
index int
|
|
)
|
|
switch {
|
|
case len(headers) > 0:
|
|
index, err = d.insertHeaders(headers, headerCheckFrequency)
|
|
|
|
case len(receipts) > 0:
|
|
index, err = d.insertReceipts(blocks, receipts)
|
|
if err == nil && blocks[len(blocks)-1].NumberU64() == d.queue.fastSyncPivot {
|
|
index, err = len(blocks)-1, d.commitHeadBlock(blocks[len(blocks)-1].Hash())
|
|
}
|
|
default:
|
|
index, err = d.insertBlocks(blocks)
|
|
}
|
|
if err != nil {
|
|
glog.V(logger.Debug).Infof("Result #%d [%x…] processing failed: %v", results[index].Header.Number, results[index].Header.Hash().Bytes()[:4], err)
|
|
d.cancel()
|
|
return
|
|
}
|
|
// Shift the results to the next batch
|
|
results = results[items:]
|
|
}
|
|
}
|
|
}
|
|
|
|
// DeliverHashes injects a new batch of hashes received from a remote node into
|
|
// the download schedule. This is usually invoked through the BlockHashesMsg by
|
|
// the protocol handler.
|
|
func (d *Downloader) DeliverHashes(id string, hashes []common.Hash) (err error) {
|
|
return d.deliver(id, d.hashCh, &hashPack{id, hashes}, hashInMeter, hashDropMeter)
|
|
}
|
|
|
|
// DeliverBlocks injects a new batch of blocks received from a remote node.
|
|
// This is usually invoked through the BlocksMsg by the protocol handler.
|
|
func (d *Downloader) DeliverBlocks(id string, blocks []*types.Block) (err error) {
|
|
return d.deliver(id, d.blockCh, &blockPack{id, blocks}, blockInMeter, blockDropMeter)
|
|
}
|
|
|
|
// DeliverHeaders injects a new batch of blck headers received from a remote
|
|
// node into the download schedule.
|
|
func (d *Downloader) DeliverHeaders(id string, headers []*types.Header) (err error) {
|
|
return d.deliver(id, d.headerCh, &headerPack{id, headers}, headerInMeter, headerDropMeter)
|
|
}
|
|
|
|
// DeliverBodies injects a new batch of block bodies received from a remote node.
|
|
func (d *Downloader) DeliverBodies(id string, transactions [][]*types.Transaction, uncles [][]*types.Header) (err error) {
|
|
return d.deliver(id, d.bodyCh, &bodyPack{id, transactions, uncles}, bodyInMeter, bodyDropMeter)
|
|
}
|
|
|
|
// DeliverReceipts injects a new batch of receipts received from a remote node.
|
|
func (d *Downloader) DeliverReceipts(id string, receipts [][]*types.Receipt) (err error) {
|
|
return d.deliver(id, d.receiptCh, &receiptPack{id, receipts}, receiptInMeter, receiptDropMeter)
|
|
}
|
|
|
|
// DeliverNodeData injects a new batch of node state data received from a remote node.
|
|
func (d *Downloader) DeliverNodeData(id string, data [][]byte) (err error) {
|
|
return d.deliver(id, d.stateCh, &statePack{id, data}, stateInMeter, stateDropMeter)
|
|
}
|
|
|
|
// deliver injects a new batch of data received from a remote node.
|
|
func (d *Downloader) deliver(id string, destCh chan dataPack, packet dataPack, inMeter, dropMeter metrics.Meter) (err error) {
|
|
// Update the delivery metrics for both good and failed deliveries
|
|
inMeter.Mark(int64(packet.Items()))
|
|
defer func() {
|
|
if err != nil {
|
|
dropMeter.Mark(int64(packet.Items()))
|
|
}
|
|
}()
|
|
// Make sure the downloader is active
|
|
if atomic.LoadInt32(&d.synchronising) == 0 {
|
|
return errNoSyncActive
|
|
}
|
|
// Deliver or abort if the sync is canceled while queuing
|
|
d.cancelLock.RLock()
|
|
cancel := d.cancelCh
|
|
d.cancelLock.RUnlock()
|
|
|
|
select {
|
|
case destCh <- packet:
|
|
return nil
|
|
|
|
case <-cancel:
|
|
return errNoSyncActive
|
|
}
|
|
}
|