1 files changed, 47 insertions, 21 deletions

diff --git a/eth/downloader/downloader.go b/eth/downloader/downloader.go
index 83e6b8d32..56671dc2e 100644
--- a/eth/downloader/downloader.go
+++ b/eth/downloader/downloader.go
@@ -54,8 +54,9 @@ type blockPack struct {
 }
 
 type syncPack struct {
-	peer *peer
-	hash common.Hash
+	peer          *peer
+	hash          common.Hash
+	ignoreInitial bool
 }
 
 func New(hasBlock hashCheckFn, insertChain chainInsertFn, currentTd currentTdFn) *Downloader {
@@ -104,11 +105,13 @@ func (d *Downloader) UnregisterPeer(id string) {
 
 func (d *Downloader) peerHandler() {
 	// itimer is used to determine when to start ignoring `minDesiredPeerCount`
-	itimer := time.NewTicker(5 * time.Second)
+	//itimer := time.NewTicker(5 * time.Second)
+	itimer := time.NewTimer(5 * time.Second)
 out:
 	for {
 		select {
 		case <-d.newPeerCh:
+			itimer.Stop()
 			// Meet the `minDesiredPeerCount` before we select our best peer
 			if len(d.peers) < minDesiredPeerCount {
 				break
@@ -137,7 +140,7 @@ func (d *Downloader) selectPeer(p *peer) {
 		}
 
 		glog.V(logger.Detail).Infoln("New peer with highest TD =", p.td)
-		d.syncCh <- syncPack{p, p.recentHash}
+		d.syncCh <- syncPack{p, p.recentHash, false}
 	}
 }
 
@@ -151,7 +154,7 @@ out:
 			// Start the fetcher. This will block the update entirely
 			// interupts need to be send to the appropriate channels
 			// respectively.
-			if err := d.startFetchingHashes(selectedPeer, sync.hash); err != nil {
+			if err := d.startFetchingHashes(selectedPeer, sync.hash, sync.ignoreInitial); err != nil {
 				// handle error
 				glog.V(logger.Debug).Infoln("Error fetching hashes:", err)
 				// XXX Reset
@@ -178,11 +181,18 @@ out:
 }
 
 // XXX Make synchronous
-func (d *Downloader) startFetchingHashes(p *peer, hash common.Hash) error {
-	glog.V(logger.Debug).Infoln("Downloading hashes")
+func (d *Downloader) startFetchingHashes(p *peer, hash common.Hash, ignoreInitial bool) error {
+	glog.V(logger.Debug).Infof("Downloading hashes (%x) from %s", hash.Bytes()[:4], p.id)
 
 	start := time.Now()
 
+	// We ignore the initial hash in some cases (e.g. we received a block without it's parent)
+	// In such circumstances we don't need to download the block so don't add it to the queue.
+	if !ignoreInitial {
+		// Add the hash to the queue first
+		d.queue.hashPool.Add(hash)
+	}
+
 	// Get the first batch of hashes
 	p.getHashes(hash)
 	atomic.StoreInt32(&d.fetchingHashes, 1)
@@ -195,7 +205,7 @@ out:
 			hashSet := set.New()
 			for _, hash := range hashes {
 				if d.hasBlock(hash) {
-					glog.V(logger.Debug).Infof("Found common hash %x\n", hash)
+					glog.V(logger.Debug).Infof("Found common hash %x\n", hash[:4])
 
 					done = true
 					break
@@ -207,7 +217,7 @@ out:
 
 			// Add hashes to the chunk set
 			// Check if we're done fetching
-			if !done {
+			if !done && len(hashes) > 0 {
 				//fmt.Println("re-fetch. current =", d.queue.hashPool.Size())
 				// Get the next set of hashes
 				p.getHashes(hashes[len(hashes)-1])
@@ -218,7 +228,7 @@ out:
 			}
 		}
 	}
-	glog.V(logger.Detail).Infoln("Download hashes: done. Took", time.Since(start))
+	glog.V(logger.Detail).Infof("Downloaded hashes (%d). Took %v\n", d.queue.hashPool.Size(), time.Since(start))
 
 	return nil
 }
@@ -242,6 +252,10 @@ out:
 			// from the available peers.
 			if d.queue.hashPool.Size() > 0 {
 				availablePeers := d.peers.get(idleState)
+				if len(availablePeers) == 0 {
+					glog.V(logger.Detail).Infoln("No peers available out of", len(d.peers))
+				}
+
 				for _, peer := range availablePeers {
 					// Get a possible chunk. If nil is returned no chunk
 					// could be returned due to no hashes available.
@@ -317,21 +331,33 @@ func (d *Downloader) AddBlock(id string, block *types.Block, td *big.Int) {
 		return
 	}
 
-	glog.V(logger.Detail).Infoln("Inserting new block from:", id)
-	d.queue.addBlock(id, block, td)
-
+	peer := d.peers.getPeer(id)
 	// if the peer is in our healthy list of peers; update the td
-	// here is a good chance to add the peer back to the list
-	if peer := d.peers.getPeer(id); peer != nil {
-		peer.mu.Lock()
-		peer.td = td
-		peer.recentHash = block.Hash()
-		peer.mu.Unlock()
+	// and add the block. Otherwise just ignore it
+	if peer == nil {
+		glog.V(logger.Detail).Infof("Ignored block from bad peer %s\n", id)
+		return
 	}
 
+	peer.mu.Lock()
+	peer.td = td
+	peer.recentHash = block.Hash()
+	peer.mu.Unlock()
+
+	glog.V(logger.Detail).Infoln("Inserting new block from:", id)
+	d.queue.addBlock(id, block, td)
+
 	// if neither go ahead to process
 	if !(d.isFetchingHashes() || d.isDownloadingBlocks()) {
-		d.process()
+		// Check if the parent of the received block is known.
+		// If the block is not know, request it otherwise, request.
+		phash := block.ParentHash()
+		if !d.hasBlock(phash) {
+			glog.V(logger.Detail).Infof("Missing parent %x, requires fetching\n", phash.Bytes()[:4])
+			d.syncCh <- syncPack{peer, peer.recentHash, true}
+		} else {
+			d.process()
+		}
 	}
 }
 
@@ -369,7 +395,7 @@ func (d *Downloader) process() error {
 			// TODO change this. This shite
 			for i, block := range blocks[:max] {
 				if !d.hasBlock(block.ParentHash()) {
-					d.syncCh <- syncPack{d.peers.bestPeer(), block.Hash()}
+					d.syncCh <- syncPack{d.peers.bestPeer(), block.Hash(), true}
 					// remove processed blocks
 					blocks = blocks[i:]