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authorSonic <sonic@dexon.org>2018-11-09 14:47:57 +0800
committerWei-Ning Huang <w@dexon.org>2019-04-09 21:32:53 +0800
commit089257a3da86184c66f666ff8e119e1ca7850357 (patch)
treef40fa6d9d4760a6171e88999deb33ebb2f546ad1 /dex/fetcher/fetcher.go
parent09f24f35eff61861c21b854a648c3afec579ff47 (diff)
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dex: copy fetcher and downloader from eth
Diffstat (limited to 'dex/fetcher/fetcher.go')
-rw-r--r--dex/fetcher/fetcher.go736
1 files changed, 736 insertions, 0 deletions
diff --git a/dex/fetcher/fetcher.go b/dex/fetcher/fetcher.go
new file mode 100644
index 000000000..f6807b5a5
--- /dev/null
+++ b/dex/fetcher/fetcher.go
@@ -0,0 +1,736 @@
+// Copyright 2015 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 fetcher contains the block announcement based synchronisation.
+package fetcher
+
+import (
+ "errors"
+ "math/rand"
+ "time"
+
+ "github.com/dexon-foundation/dexon/common"
+ "github.com/dexon-foundation/dexon/common/prque"
+ "github.com/dexon-foundation/dexon/consensus"
+ "github.com/dexon-foundation/dexon/core/types"
+ "github.com/dexon-foundation/dexon/log"
+)
+
+const (
+ arriveTimeout = 500 * time.Millisecond // Time allowance before an announced block is explicitly requested
+ gatherSlack = 100 * time.Millisecond // Interval used to collate almost-expired announces with fetches
+ fetchTimeout = 5 * time.Second // Maximum allotted time to return an explicitly requested block
+ maxUncleDist = 7 // Maximum allowed backward distance from the chain head
+ maxQueueDist = 32 // Maximum allowed distance from the chain head to queue
+ hashLimit = 256 // Maximum number of unique blocks a peer may have announced
+ blockLimit = 64 // Maximum number of unique blocks a peer may have delivered
+)
+
+var (
+ errTerminated = errors.New("terminated")
+)
+
+// blockRetrievalFn is a callback type for retrieving a block from the local chain.
+type blockRetrievalFn func(common.Hash) *types.Block
+
+// headerRequesterFn is a callback type for sending a header retrieval request.
+type headerRequesterFn func(common.Hash) error
+
+// bodyRequesterFn is a callback type for sending a body retrieval request.
+type bodyRequesterFn func([]common.Hash) error
+
+// headerVerifierFn is a callback type to verify a block's header for fast propagation.
+type headerVerifierFn func(header *types.Header) error
+
+// blockBroadcasterFn is a callback type for broadcasting a block to connected peers.
+type blockBroadcasterFn func(block *types.Block, propagate bool)
+
+// chainHeightFn is a callback type to retrieve the current chain height.
+type chainHeightFn func() uint64
+
+// chainInsertFn is a callback type to insert a batch of blocks into the local chain.
+type chainInsertFn func(types.Blocks) (int, error)
+
+// peerDropFn is a callback type for dropping a peer detected as malicious.
+type peerDropFn func(id string)
+
+// announce is the hash notification of the availability of a new block in the
+// network.
+type announce struct {
+ hash common.Hash // Hash of the block being announced
+ number uint64 // Number of the block being announced (0 = unknown | old protocol)
+ header *types.Header // Header of the block partially reassembled (new protocol)
+ time time.Time // Timestamp of the announcement
+
+ origin string // Identifier of the peer originating the notification
+
+ fetchHeader headerRequesterFn // Fetcher function to retrieve the header of an announced block
+ fetchBodies bodyRequesterFn // Fetcher function to retrieve the body of an announced block
+}
+
+// headerFilterTask represents a batch of headers needing fetcher filtering.
+type headerFilterTask struct {
+ peer string // The source peer of block headers
+ headers []*types.Header // Collection of headers to filter
+ time time.Time // Arrival time of the headers
+}
+
+// bodyFilterTask represents a batch of block bodies (transactions and uncles)
+// needing fetcher filtering.
+type bodyFilterTask struct {
+ peer string // The source peer of block bodies
+ transactions [][]*types.Transaction // Collection of transactions per block bodies
+ uncles [][]*types.Header // Collection of uncles per block bodies
+ time time.Time // Arrival time of the blocks' contents
+}
+
+// inject represents a schedules import operation.
+type inject struct {
+ origin string
+ block *types.Block
+}
+
+// Fetcher is responsible for accumulating block announcements from various peers
+// and scheduling them for retrieval.
+type Fetcher struct {
+ // Various event channels
+ notify chan *announce
+ inject chan *inject
+
+ blockFilter chan chan []*types.Block
+ headerFilter chan chan *headerFilterTask
+ bodyFilter chan chan *bodyFilterTask
+
+ done chan common.Hash
+ quit chan struct{}
+
+ // Announce states
+ announces map[string]int // Per peer announce counts to prevent memory exhaustion
+ announced map[common.Hash][]*announce // Announced blocks, scheduled for fetching
+ fetching map[common.Hash]*announce // Announced blocks, currently fetching
+ fetched map[common.Hash][]*announce // Blocks with headers fetched, scheduled for body retrieval
+ completing map[common.Hash]*announce // Blocks with headers, currently body-completing
+
+ // Block cache
+ queue *prque.Prque // Queue containing the import operations (block number sorted)
+ queues map[string]int // Per peer block counts to prevent memory exhaustion
+ queued map[common.Hash]*inject // Set of already queued blocks (to dedupe imports)
+
+ // Callbacks
+ getBlock blockRetrievalFn // Retrieves a block from the local chain
+ verifyHeader headerVerifierFn // Checks if a block's headers have a valid proof of work
+ broadcastBlock blockBroadcasterFn // Broadcasts a block to connected peers
+ chainHeight chainHeightFn // Retrieves the current chain's height
+ insertChain chainInsertFn // Injects a batch of blocks into the chain
+ dropPeer peerDropFn // Drops a peer for misbehaving
+
+ // Testing hooks
+ announceChangeHook func(common.Hash, bool) // Method to call upon adding or deleting a hash from the announce list
+ queueChangeHook func(common.Hash, bool) // Method to call upon adding or deleting a block from the import queue
+ fetchingHook func([]common.Hash) // Method to call upon starting a block (eth/61) or header (eth/62) fetch
+ completingHook func([]common.Hash) // Method to call upon starting a block body fetch (eth/62)
+ importedHook func(*types.Block) // Method to call upon successful block import (both eth/61 and eth/62)
+}
+
+// New creates a block fetcher to retrieve blocks based on hash announcements.
+func New(getBlock blockRetrievalFn, verifyHeader headerVerifierFn, broadcastBlock blockBroadcasterFn, chainHeight chainHeightFn, insertChain chainInsertFn, dropPeer peerDropFn) *Fetcher {
+ return &Fetcher{
+ notify: make(chan *announce),
+ inject: make(chan *inject),
+ blockFilter: make(chan chan []*types.Block),
+ headerFilter: make(chan chan *headerFilterTask),
+ bodyFilter: make(chan chan *bodyFilterTask),
+ done: make(chan common.Hash),
+ quit: make(chan struct{}),
+ announces: make(map[string]int),
+ announced: make(map[common.Hash][]*announce),
+ fetching: make(map[common.Hash]*announce),
+ fetched: make(map[common.Hash][]*announce),
+ completing: make(map[common.Hash]*announce),
+ queue: prque.New(nil),
+ queues: make(map[string]int),
+ queued: make(map[common.Hash]*inject),
+ getBlock: getBlock,
+ verifyHeader: verifyHeader,
+ broadcastBlock: broadcastBlock,
+ chainHeight: chainHeight,
+ insertChain: insertChain,
+ dropPeer: dropPeer,
+ }
+}
+
+// Start boots up the announcement based synchroniser, accepting and processing
+// hash notifications and block fetches until termination requested.
+func (f *Fetcher) Start() {
+ go f.loop()
+}
+
+// Stop terminates the announcement based synchroniser, canceling all pending
+// operations.
+func (f *Fetcher) Stop() {
+ close(f.quit)
+}
+
+// Notify announces the fetcher of the potential availability of a new block in
+// the network.
+func (f *Fetcher) Notify(peer string, hash common.Hash, number uint64, time time.Time,
+ headerFetcher headerRequesterFn, bodyFetcher bodyRequesterFn) error {
+ block := &announce{
+ hash: hash,
+ number: number,
+ time: time,
+ origin: peer,
+ fetchHeader: headerFetcher,
+ fetchBodies: bodyFetcher,
+ }
+ select {
+ case f.notify <- block:
+ return nil
+ case <-f.quit:
+ return errTerminated
+ }
+}
+
+// Enqueue tries to fill gaps the fetcher's future import queue.
+func (f *Fetcher) Enqueue(peer string, block *types.Block) error {
+ op := &inject{
+ origin: peer,
+ block: block,
+ }
+ select {
+ case f.inject <- op:
+ return nil
+ case <-f.quit:
+ return errTerminated
+ }
+}
+
+// FilterHeaders extracts all the headers that were explicitly requested by the fetcher,
+// returning those that should be handled differently.
+func (f *Fetcher) FilterHeaders(peer string, headers []*types.Header, time time.Time) []*types.Header {
+ log.Trace("Filtering headers", "peer", peer, "headers", len(headers))
+
+ // Send the filter channel to the fetcher
+ filter := make(chan *headerFilterTask)
+
+ select {
+ case f.headerFilter <- filter:
+ case <-f.quit:
+ return nil
+ }
+ // Request the filtering of the header list
+ select {
+ case filter <- &headerFilterTask{peer: peer, headers: headers, time: time}:
+ case <-f.quit:
+ return nil
+ }
+ // Retrieve the headers remaining after filtering
+ select {
+ case task := <-filter:
+ return task.headers
+ case <-f.quit:
+ return nil
+ }
+}
+
+// FilterBodies extracts all the block bodies that were explicitly requested by
+// the fetcher, returning those that should be handled differently.
+func (f *Fetcher) FilterBodies(peer string, transactions [][]*types.Transaction, uncles [][]*types.Header, time time.Time) ([][]*types.Transaction, [][]*types.Header) {
+ log.Trace("Filtering bodies", "peer", peer, "txs", len(transactions), "uncles", len(uncles))
+
+ // Send the filter channel to the fetcher
+ filter := make(chan *bodyFilterTask)
+
+ select {
+ case f.bodyFilter <- filter:
+ case <-f.quit:
+ return nil, nil
+ }
+ // Request the filtering of the body list
+ select {
+ case filter <- &bodyFilterTask{peer: peer, transactions: transactions, uncles: uncles, time: time}:
+ case <-f.quit:
+ return nil, nil
+ }
+ // Retrieve the bodies remaining after filtering
+ select {
+ case task := <-filter:
+ return task.transactions, task.uncles
+ case <-f.quit:
+ return nil, nil
+ }
+}
+
+// Loop is the main fetcher loop, checking and processing various notification
+// events.
+func (f *Fetcher) loop() {
+ // Iterate the block fetching until a quit is requested
+ fetchTimer := time.NewTimer(0)
+ completeTimer := time.NewTimer(0)
+
+ for {
+ // Clean up any expired block fetches
+ for hash, announce := range f.fetching {
+ if time.Since(announce.time) > fetchTimeout {
+ f.forgetHash(hash)
+ }
+ }
+ // Import any queued blocks that could potentially fit
+ height := f.chainHeight()
+ for !f.queue.Empty() {
+ op := f.queue.PopItem().(*inject)
+ hash := op.block.Hash()
+ if f.queueChangeHook != nil {
+ f.queueChangeHook(hash, false)
+ }
+ // If too high up the chain or phase, continue later
+ number := op.block.NumberU64()
+ if number > height+1 {
+ f.queue.Push(op, -int64(number))
+ if f.queueChangeHook != nil {
+ f.queueChangeHook(hash, true)
+ }
+ break
+ }
+ // Otherwise if fresh and still unknown, try and import
+ if number+maxUncleDist < height || f.getBlock(hash) != nil {
+ f.forgetBlock(hash)
+ continue
+ }
+ f.insert(op.origin, op.block)
+ }
+ // Wait for an outside event to occur
+ select {
+ case <-f.quit:
+ // Fetcher terminating, abort all operations
+ return
+
+ case notification := <-f.notify:
+ // A block was announced, make sure the peer isn't DOSing us
+ propAnnounceInMeter.Mark(1)
+
+ count := f.announces[notification.origin] + 1
+ if count > hashLimit {
+ log.Debug("Peer exceeded outstanding announces", "peer", notification.origin, "limit", hashLimit)
+ propAnnounceDOSMeter.Mark(1)
+ break
+ }
+ // If we have a valid block number, check that it's potentially useful
+ if notification.number > 0 {
+ if dist := int64(notification.number) - int64(f.chainHeight()); dist < -maxUncleDist || dist > maxQueueDist {
+ log.Debug("Peer discarded announcement", "peer", notification.origin, "number", notification.number, "hash", notification.hash, "distance", dist)
+ propAnnounceDropMeter.Mark(1)
+ break
+ }
+ }
+ // All is well, schedule the announce if block's not yet downloading
+ if _, ok := f.fetching[notification.hash]; ok {
+ break
+ }
+ if _, ok := f.completing[notification.hash]; ok {
+ break
+ }
+ f.announces[notification.origin] = count
+ f.announced[notification.hash] = append(f.announced[notification.hash], notification)
+ if f.announceChangeHook != nil && len(f.announced[notification.hash]) == 1 {
+ f.announceChangeHook(notification.hash, true)
+ }
+ if len(f.announced) == 1 {
+ f.rescheduleFetch(fetchTimer)
+ }
+
+ case op := <-f.inject:
+ // A direct block insertion was requested, try and fill any pending gaps
+ propBroadcastInMeter.Mark(1)
+ f.enqueue(op.origin, op.block)
+
+ case hash := <-f.done:
+ // A pending import finished, remove all traces of the notification
+ f.forgetHash(hash)
+ f.forgetBlock(hash)
+
+ case <-fetchTimer.C:
+ // At least one block's timer ran out, check for needing retrieval
+ request := make(map[string][]common.Hash)
+
+ for hash, announces := range f.announced {
+ if time.Since(announces[0].time) > arriveTimeout-gatherSlack {
+ // Pick a random peer to retrieve from, reset all others
+ announce := announces[rand.Intn(len(announces))]
+ f.forgetHash(hash)
+
+ // If the block still didn't arrive, queue for fetching
+ if f.getBlock(hash) == nil {
+ request[announce.origin] = append(request[announce.origin], hash)
+ f.fetching[hash] = announce
+ }
+ }
+ }
+ // Send out all block header requests
+ for peer, hashes := range request {
+ log.Trace("Fetching scheduled headers", "peer", peer, "list", hashes)
+
+ // Create a closure of the fetch and schedule in on a new thread
+ fetchHeader, hashes := f.fetching[hashes[0]].fetchHeader, hashes
+ go func() {
+ if f.fetchingHook != nil {
+ f.fetchingHook(hashes)
+ }
+ for _, hash := range hashes {
+ headerFetchMeter.Mark(1)
+ fetchHeader(hash) // Suboptimal, but protocol doesn't allow batch header retrievals
+ }
+ }()
+ }
+ // Schedule the next fetch if blocks are still pending
+ f.rescheduleFetch(fetchTimer)
+
+ case <-completeTimer.C:
+ // At least one header's timer ran out, retrieve everything
+ request := make(map[string][]common.Hash)
+
+ for hash, announces := range f.fetched {
+ // Pick a random peer to retrieve from, reset all others
+ announce := announces[rand.Intn(len(announces))]
+ f.forgetHash(hash)
+
+ // If the block still didn't arrive, queue for completion
+ if f.getBlock(hash) == nil {
+ request[announce.origin] = append(request[announce.origin], hash)
+ f.completing[hash] = announce
+ }
+ }
+ // Send out all block body requests
+ for peer, hashes := range request {
+ log.Trace("Fetching scheduled bodies", "peer", peer, "list", hashes)
+
+ // Create a closure of the fetch and schedule in on a new thread
+ if f.completingHook != nil {
+ f.completingHook(hashes)
+ }
+ bodyFetchMeter.Mark(int64(len(hashes)))
+ go f.completing[hashes[0]].fetchBodies(hashes)
+ }
+ // Schedule the next fetch if blocks are still pending
+ f.rescheduleComplete(completeTimer)
+
+ case filter := <-f.headerFilter:
+ // Headers arrived from a remote peer. Extract those that were explicitly
+ // requested by the fetcher, and return everything else so it's delivered
+ // to other parts of the system.
+ var task *headerFilterTask
+ select {
+ case task = <-filter:
+ case <-f.quit:
+ return
+ }
+ headerFilterInMeter.Mark(int64(len(task.headers)))
+
+ // Split the batch of headers into unknown ones (to return to the caller),
+ // known incomplete ones (requiring body retrievals) and completed blocks.
+ unknown, incomplete, complete := []*types.Header{}, []*announce{}, []*types.Block{}
+ for _, header := range task.headers {
+ hash := header.Hash()
+
+ // Filter fetcher-requested headers from other synchronisation algorithms
+ if announce := f.fetching[hash]; announce != nil && announce.origin == task.peer && f.fetched[hash] == nil && f.completing[hash] == nil && f.queued[hash] == nil {
+ // If the delivered header does not match the promised number, drop the announcer
+ if header.Number.Uint64() != announce.number {
+ log.Trace("Invalid block number fetched", "peer", announce.origin, "hash", header.Hash(), "announced", announce.number, "provided", header.Number)
+ f.dropPeer(announce.origin)
+ f.forgetHash(hash)
+ continue
+ }
+ // Only keep if not imported by other means
+ if f.getBlock(hash) == nil {
+ announce.header = header
+ announce.time = task.time
+
+ // If the block is empty (header only), short circuit into the final import queue
+ if header.TxHash == types.DeriveSha(types.Transactions{}) && header.UncleHash == types.CalcUncleHash([]*types.Header{}) {
+ log.Trace("Block empty, skipping body retrieval", "peer", announce.origin, "number", header.Number, "hash", header.Hash())
+
+ block := types.NewBlockWithHeader(header)
+ block.ReceivedAt = task.time
+
+ complete = append(complete, block)
+ f.completing[hash] = announce
+ continue
+ }
+ // Otherwise add to the list of blocks needing completion
+ incomplete = append(incomplete, announce)
+ } else {
+ log.Trace("Block already imported, discarding header", "peer", announce.origin, "number", header.Number, "hash", header.Hash())
+ f.forgetHash(hash)
+ }
+ } else {
+ // Fetcher doesn't know about it, add to the return list
+ unknown = append(unknown, header)
+ }
+ }
+ headerFilterOutMeter.Mark(int64(len(unknown)))
+ select {
+ case filter <- &headerFilterTask{headers: unknown, time: task.time}:
+ case <-f.quit:
+ return
+ }
+ // Schedule the retrieved headers for body completion
+ for _, announce := range incomplete {
+ hash := announce.header.Hash()
+ if _, ok := f.completing[hash]; ok {
+ continue
+ }
+ f.fetched[hash] = append(f.fetched[hash], announce)
+ if len(f.fetched) == 1 {
+ f.rescheduleComplete(completeTimer)
+ }
+ }
+ // Schedule the header-only blocks for import
+ for _, block := range complete {
+ if announce := f.completing[block.Hash()]; announce != nil {
+ f.enqueue(announce.origin, block)
+ }
+ }
+
+ case filter := <-f.bodyFilter:
+ // Block bodies arrived, extract any explicitly requested blocks, return the rest
+ var task *bodyFilterTask
+ select {
+ case task = <-filter:
+ case <-f.quit:
+ return
+ }
+ bodyFilterInMeter.Mark(int64(len(task.transactions)))
+
+ blocks := []*types.Block{}
+ for i := 0; i < len(task.transactions) && i < len(task.uncles); i++ {
+ // Match up a body to any possible completion request
+ matched := false
+
+ for hash, announce := range f.completing {
+ if f.queued[hash] == nil {
+ txnHash := types.DeriveSha(types.Transactions(task.transactions[i]))
+ uncleHash := types.CalcUncleHash(task.uncles[i])
+
+ if txnHash == announce.header.TxHash && uncleHash == announce.header.UncleHash && announce.origin == task.peer {
+ // Mark the body matched, reassemble if still unknown
+ matched = true
+
+ if f.getBlock(hash) == nil {
+ block := types.NewBlockWithHeader(announce.header).WithBody(task.transactions[i], task.uncles[i])
+ block.ReceivedAt = task.time
+
+ blocks = append(blocks, block)
+ } else {
+ f.forgetHash(hash)
+ }
+ }
+ }
+ }
+ if matched {
+ task.transactions = append(task.transactions[:i], task.transactions[i+1:]...)
+ task.uncles = append(task.uncles[:i], task.uncles[i+1:]...)
+ i--
+ continue
+ }
+ }
+
+ bodyFilterOutMeter.Mark(int64(len(task.transactions)))
+ select {
+ case filter <- task:
+ case <-f.quit:
+ return
+ }
+ // Schedule the retrieved blocks for ordered import
+ for _, block := range blocks {
+ if announce := f.completing[block.Hash()]; announce != nil {
+ f.enqueue(announce.origin, block)
+ }
+ }
+ }
+ }
+}
+
+// rescheduleFetch resets the specified fetch timer to the next announce timeout.
+func (f *Fetcher) rescheduleFetch(fetch *time.Timer) {
+ // Short circuit if no blocks are announced
+ if len(f.announced) == 0 {
+ return
+ }
+ // Otherwise find the earliest expiring announcement
+ earliest := time.Now()
+ for _, announces := range f.announced {
+ if earliest.After(announces[0].time) {
+ earliest = announces[0].time
+ }
+ }
+ fetch.Reset(arriveTimeout - time.Since(earliest))
+}
+
+// rescheduleComplete resets the specified completion timer to the next fetch timeout.
+func (f *Fetcher) rescheduleComplete(complete *time.Timer) {
+ // Short circuit if no headers are fetched
+ if len(f.fetched) == 0 {
+ return
+ }
+ // Otherwise find the earliest expiring announcement
+ earliest := time.Now()
+ for _, announces := range f.fetched {
+ if earliest.After(announces[0].time) {
+ earliest = announces[0].time
+ }
+ }
+ complete.Reset(gatherSlack - time.Since(earliest))
+}
+
+// enqueue schedules a new future import operation, if the block to be imported
+// has not yet been seen.
+func (f *Fetcher) enqueue(peer string, block *types.Block) {
+ hash := block.Hash()
+
+ // Ensure the peer isn't DOSing us
+ count := f.queues[peer] + 1
+ if count > blockLimit {
+ log.Debug("Discarded propagated block, exceeded allowance", "peer", peer, "number", block.Number(), "hash", hash, "limit", blockLimit)
+ propBroadcastDOSMeter.Mark(1)
+ f.forgetHash(hash)
+ return
+ }
+ // Discard any past or too distant blocks
+ if dist := int64(block.NumberU64()) - int64(f.chainHeight()); dist < -maxUncleDist || dist > maxQueueDist {
+ log.Debug("Discarded propagated block, too far away", "peer", peer, "number", block.Number(), "hash", hash, "distance", dist)
+ propBroadcastDropMeter.Mark(1)
+ f.forgetHash(hash)
+ return
+ }
+ // Schedule the block for future importing
+ if _, ok := f.queued[hash]; !ok {
+ op := &inject{
+ origin: peer,
+ block: block,
+ }
+ f.queues[peer] = count
+ f.queued[hash] = op
+ f.queue.Push(op, -int64(block.NumberU64()))
+ if f.queueChangeHook != nil {
+ f.queueChangeHook(op.block.Hash(), true)
+ }
+ log.Debug("Queued propagated block", "peer", peer, "number", block.Number(), "hash", hash, "queued", f.queue.Size())
+ }
+}
+
+// insert spawns a new goroutine to run a block insertion into the chain. If the
+// block's number is at the same height as the current import phase, it updates
+// the phase states accordingly.
+func (f *Fetcher) insert(peer string, block *types.Block) {
+ hash := block.Hash()
+
+ // Run the import on a new thread
+ log.Debug("Importing propagated block", "peer", peer, "number", block.Number(), "hash", hash)
+ go func() {
+ defer func() { f.done <- hash }()
+
+ // If the parent's unknown, abort insertion
+ parent := f.getBlock(block.ParentHash())
+ if parent == nil {
+ log.Debug("Unknown parent of propagated block", "peer", peer, "number", block.Number(), "hash", hash, "parent", block.ParentHash())
+ return
+ }
+ // Quickly validate the header and propagate the block if it passes
+ switch err := f.verifyHeader(block.Header()); err {
+ case nil:
+ // All ok, quickly propagate to our peers
+ propBroadcastOutTimer.UpdateSince(block.ReceivedAt)
+ go f.broadcastBlock(block, true)
+
+ case consensus.ErrFutureBlock:
+ // Weird future block, don't fail, but neither propagate
+
+ default:
+ // Something went very wrong, drop the peer
+ log.Debug("Propagated block verification failed", "peer", peer, "number", block.Number(), "hash", hash, "err", err)
+ f.dropPeer(peer)
+ return
+ }
+ // Run the actual import and log any issues
+ if _, err := f.insertChain(types.Blocks{block}); err != nil {
+ log.Debug("Propagated block import failed", "peer", peer, "number", block.Number(), "hash", hash, "err", err)
+ return
+ }
+ // If import succeeded, broadcast the block
+ propAnnounceOutTimer.UpdateSince(block.ReceivedAt)
+ go f.broadcastBlock(block, false)
+
+ // Invoke the testing hook if needed
+ if f.importedHook != nil {
+ f.importedHook(block)
+ }
+ }()
+}
+
+// forgetHash removes all traces of a block announcement from the fetcher's
+// internal state.
+func (f *Fetcher) forgetHash(hash common.Hash) {
+ // Remove all pending announces and decrement DOS counters
+ for _, announce := range f.announced[hash] {
+ f.announces[announce.origin]--
+ if f.announces[announce.origin] == 0 {
+ delete(f.announces, announce.origin)
+ }
+ }
+ delete(f.announced, hash)
+ if f.announceChangeHook != nil {
+ f.announceChangeHook(hash, false)
+ }
+ // Remove any pending fetches and decrement the DOS counters
+ if announce := f.fetching[hash]; announce != nil {
+ f.announces[announce.origin]--
+ if f.announces[announce.origin] == 0 {
+ delete(f.announces, announce.origin)
+ }
+ delete(f.fetching, hash)
+ }
+
+ // Remove any pending completion requests and decrement the DOS counters
+ for _, announce := range f.fetched[hash] {
+ f.announces[announce.origin]--
+ if f.announces[announce.origin] == 0 {
+ delete(f.announces, announce.origin)
+ }
+ }
+ delete(f.fetched, hash)
+
+ // Remove any pending completions and decrement the DOS counters
+ if announce := f.completing[hash]; announce != nil {
+ f.announces[announce.origin]--
+ if f.announces[announce.origin] == 0 {
+ delete(f.announces, announce.origin)
+ }
+ delete(f.completing, hash)
+ }
+}
+
+// forgetBlock removes all traces of a queued block from the fetcher's internal
+// state.
+func (f *Fetcher) forgetBlock(hash common.Hash) {
+ if insert := f.queued[hash]; insert != nil {
+ f.queues[insert.origin]--
+ if f.queues[insert.origin] == 0 {
+ delete(f.queues, insert.origin)
+ }
+ delete(f.queued, hash)
+ }
+}