swarm/storage: fix chunker when reader is broken

* brokenLimitedReader gives error after half size
* TestRandomBrokenData tests chunker with broken reader
* add blocking quitC (instead of errC) and use errC only for errors
* don't close chunkC in tester Split,
* use quitC to quit chunk storage loop

4 files changed, 89 insertions, 101 deletions

diff --git a/swarm/storage/chunker.go b/swarm/storage/chunker.go
index 4c8551da9..b22b4c813 100644
--- a/swarm/storage/chunker.go
+++ b/swarm/storage/chunker.go
@@ -23,8 +23,6 @@ import (
 	"hash"
 	"io"
 	"sync"
-	// "github.com/ethereum/go-ethereum/logger"
-	// "github.com/ethereum/go-ethereum/logger/glog"
 )
 
 /*
@@ -124,12 +122,13 @@ func (self *TreeChunker) Split(data io.Reader, size int64, chunkC chan *Chunk, s
 	jobC := make(chan *hashJob, 2*processors)
 	wg := &sync.WaitGroup{}
 	errC := make(chan error)
+	quitC := make(chan bool)
 
 	// wwg = workers waitgroup keeps track of hashworkers spawned by this split call
 	if wwg != nil {
 		wwg.Add(1)
 	}
-	go self.hashWorker(jobC, chunkC, errC, swg, wwg)
+	go self.hashWorker(jobC, chunkC, errC, quitC, swg, wwg)
 
 	depth := 0
 	treeSize := self.chunkSize
@@ -141,11 +140,10 @@ func (self *TreeChunker) Split(data io.Reader, size int64, chunkC chan *Chunk, s
 	}
 
 	key := make([]byte, self.hashFunc().Size())
-	// glog.V(logger.Detail).Infof("split request received for data (%v bytes, depth: %v)", size, depth)
 	// this waitgroup member is released after the root hash is calculated
 	wg.Add(1)
 	//launch actual recursive function passing the waitgroups
-	go self.split(depth, treeSize/self.branches, key, data, size, jobC, chunkC, errC, wg, swg, wwg)
+	go self.split(depth, treeSize/self.branches, key, data, size, jobC, chunkC, errC, quitC, wg, swg, wwg)
 
 	// closes internal error channel if all subprocesses in the workgroup finished
 	go func() {
@@ -153,7 +151,6 @@ func (self *TreeChunker) Split(data io.Reader, size int64, chunkC chan *Chunk, s
 		wg.Wait()
 		// if storage waitgroup is non-nil, we wait for storage to finish too
 		if swg != nil {
-			// glog.V(logger.Detail).Infof("Waiting for storage to finish")
 			swg.Wait()
 		}
 		close(errC)
@@ -162,14 +159,15 @@ func (self *TreeChunker) Split(data io.Reader, size int64, chunkC chan *Chunk, s
 	select {
 	case err := <-errC:
 		if err != nil {
+			close(quitC)
 			return nil, err
 		}
-		//
+		//TODO: add a timeout
 	}
 	return key, nil
 }
 
-func (self *TreeChunker) split(depth int, treeSize int64, key Key, data io.Reader, size int64, jobC chan *hashJob, chunkC chan *Chunk, errC chan error, parentWg, swg, wwg *sync.WaitGroup) {
+func (self *TreeChunker) split(depth int, treeSize int64, key Key, data io.Reader, size int64, jobC chan *hashJob, chunkC chan *Chunk, errC chan error, quitC chan bool, parentWg, swg, wwg *sync.WaitGroup) {
 
 	for depth > 0 && size < treeSize {
 		treeSize /= self.branches
@@ -180,17 +178,20 @@ func (self *TreeChunker) split(depth int, treeSize int64, key Key, data io.Reade
 		// leaf nodes -> content chunks
 		chunkData := make([]byte, size+8)
 		binary.LittleEndian.PutUint64(chunkData[0:8], uint64(size))
-		data.Read(chunkData[8:])
+		_, err := data.Read(chunkData[8:])
+		if err != nil {
+			errC <- err
+			return
+		}
 		select {
 		case jobC <- &hashJob{key, chunkData, size, parentWg}:
-		case <-errC:
+		case <-quitC:
 		}
-		// glog.V(logger.Detail).Infof("read %v", size)
 		return
 	}
+	// dept > 0
 	// intermediate chunk containing child nodes hashes
 	branchCnt := int64((size + treeSize - 1) / treeSize)
-	// glog.V(logger.Detail).Infof("intermediate node: setting branches: %v, depth: %v, max subtree size: %v, data size: %v", branches, depth, treeSize, size)
 
 	var chunk []byte = make([]byte, branchCnt*self.hashSize+8)
 	var pos, i int64
@@ -210,7 +211,7 @@ func (self *TreeChunker) split(depth int, treeSize int64, key Key, data io.Reade
 		subTreeKey := chunk[8+i*self.hashSize : 8+(i+1)*self.hashSize]
 
 		childrenWg.Add(1)
-		self.split(depth-1, treeSize/self.branches, subTreeKey, data, secSize, jobC, chunkC, errC, childrenWg, swg, wwg)
+		self.split(depth-1, treeSize/self.branches, subTreeKey, data, secSize, jobC, chunkC, errC, quitC, childrenWg, swg, wwg)
 
 		i++
 		pos += treeSize
@@ -224,15 +225,15 @@ func (self *TreeChunker) split(depth int, treeSize int64, key Key, data io.Reade
 			wwg.Add(1)
 		}
 		self.workerCount++
-		go self.hashWorker(jobC, chunkC, errC, swg, wwg)
+		go self.hashWorker(jobC, chunkC, errC, quitC, swg, wwg)
 	}
 	select {
 	case jobC <- &hashJob{key, chunk, size, parentWg}:
-	case <-errC:
+	case <-quitC:
 	}
 }
 
-func (self *TreeChunker) hashWorker(jobC chan *hashJob, chunkC chan *Chunk, errC chan error, swg, wwg *sync.WaitGroup) {
+func (self *TreeChunker) hashWorker(jobC chan *hashJob, chunkC chan *Chunk, errC chan error, quitC chan bool, swg, wwg *sync.WaitGroup) {
 	hasher := self.hashFunc()
 	if wwg != nil {
 		defer wwg.Done()
@@ -247,8 +248,7 @@ func (self *TreeChunker) hashWorker(jobC chan *hashJob, chunkC chan *Chunk, errC
 			// now we got the hashes in the chunk, then hash the chunks
 			hasher.Reset()
 			self.hashChunk(hasher, job, chunkC, swg)
-			// glog.V(logger.Detail).Infof("hash chunk (%v)", job.size)
-		case <-errC:
+		case <-quitC:
 			return
 		}
 	}
@@ -276,6 +276,7 @@ func (self *TreeChunker) hashChunk(hasher hash.Hash, job *hashJob, chunkC chan *
 		}
 	}
 	job.parentWg.Done()
+
 	if chunkC != nil {
 		chunkC <- newChunk
 	}
@@ -328,7 +329,6 @@ func (self *LazyChunkReader) Size(quitC chan bool) (n int64, err error) {
 func (self *LazyChunkReader) ReadAt(b []byte, off int64) (read int, err error) {
 	// this is correct, a swarm doc cannot be zero length, so no EOF is expected
 	if len(b) == 0 {
-		// glog.V(logger.Detail).Infof("Size query for %v", chunk.Key.Log())
 		return 0, nil
 	}
 	quitC := make(chan bool)
@@ -336,13 +336,10 @@ func (self *LazyChunkReader) ReadAt(b []byte, off int64) (read int, err error) {
 	if err != nil {
 		return 0, err
 	}
-	// glog.V(logger.Detail).Infof("readAt: len(b): %v, off: %v, size: %v ", len(b), off, size)
 
 	errC := make(chan error)
-	// glog.V(logger.Detail).Infof("readAt: reading %v into %d bytes at offset %d.", self.chunk.Key.Log(), len(b), off)
 
 	// }
-	// glog.V(logger.Detail).Infof("-> want: %v, off: %v size: %v ", want, off, self.size)
 	var treeSize int64
 	var depth int
 	// calculate depth and max treeSize
@@ -364,22 +361,16 @@ func (self *LazyChunkReader) ReadAt(b []byte, off int64) (read int, err error) {
 
 		return 0, err
 	}
-	// glog.V(logger.Detail).Infof("ReadAt received %v", err)
-	// glog.V(logger.Detail).Infof("end: len(b): %v, off: %v, size: %v ", len(b), off, size)
 	if off+int64(len(b)) >= size {
-		// glog.V(logger.Detail).Infof(" len(b): %v EOF", len(b))
 		return len(b), io.EOF
 	}
-	// glog.V(logger.Detail).Infof("ReadAt returning at %d: %v", read, err)
 	return len(b), nil
 }
 
 func (self *LazyChunkReader) join(b []byte, off int64, eoff int64, depth int, treeSize int64, chunk *Chunk, parentWg *sync.WaitGroup, errC chan error, quitC chan bool) {
 	defer parentWg.Done()
 	// return NewDPA(&LocalStore{})
-	// glog.V(logger.Detail).Infof("inh len(b): %v, off: %v eoff: %v ", len(b), off, eoff)
 
-	// glog.V(logger.Detail).Infof("depth: %v, loff: %v, eoff: %v, chunk.Size: %v, treeSize: %v", depth, off, eoff, chunk.Size, treeSize)
 
 	// chunk.Size = int64(binary.LittleEndian.Uint64(chunk.SData[0:8]))
 
@@ -391,7 +382,6 @@ func (self *LazyChunkReader) join(b []byte, off int64, eoff int64, depth int, tr
 
 	// leaf chunk found
 	if depth == 0 {
-		// glog.V(logger.Detail).Infof("depth: %v, len(b): %v, off: %v, eoff: %v, chunk.Size: %v %v, treeSize: %v", depth, len(b), off, eoff, chunk.Size, len(chunk.SData), treeSize)
 		extra := 8 + eoff - int64(len(chunk.SData))
 		if extra > 0 {
 			eoff -= extra
@@ -406,7 +396,6 @@ func (self *LazyChunkReader) join(b []byte, off int64, eoff int64, depth int, tr
 
 	wg := &sync.WaitGroup{}
 	defer wg.Wait()
-	// glog.V(logger.Detail).Infof("start %v,end %v", start, end)
 
 	for i := start; i < end; i++ {
 		soff := i * treeSize
@@ -425,7 +414,6 @@ func (self *LazyChunkReader) join(b []byte, off int64, eoff int64, depth int, tr
 		wg.Add(1)
 		go func(j int64) {
 			childKey := chunk.SData[8+j*self.hashSize : 8+(j+1)*self.hashSize]
-			// glog.V(logger.Detail).Infof("subtree ind.ex: %v -> %v", j, childKey.Log())
 			chunk := retrieve(childKey, self.chunkC, quitC)
 			if chunk == nil {
 				select {
@@ -450,7 +438,6 @@ func retrieve(key Key, chunkC chan *Chunk, quitC chan bool) *Chunk {
 		Key: key,
 		C:   make(chan bool), // close channel to signal data delivery
 	}
-	// glog.V(logger.Detail).Infof("chunk data sent for %v (key interval in chunk %v-%v)", ch.Key.Log(), j*self.chunker.hashSize, (j+1)*self.chunker.hashSize)
 	// submit chunk for retrieval
 	select {
 	case chunkC <- chunk: // submit retrieval request, someone should be listening on the other side (or we will time out globally)
@@ -464,7 +451,6 @@ func retrieve(key Key, chunkC chan *Chunk, quitC chan bool) *Chunk {
 		// this is how we control process leakage (quitC is closed once join is finished (after timeout))
 		return nil
 	case <-chunk.C: // bells are ringing, data have been delivered
-		// glog.V(logger.Detail).Infof("chunk data received")
 	}
 	if len(chunk.SData) == 0 {
 		return nil // chunk.Size = int64(binary.LittleEndian.Uint64(chunk.SData[0:8]))
@@ -476,7 +462,6 @@ func retrieve(key Key, chunkC chan *Chunk, quitC chan bool) *Chunk {
 // Read keeps a cursor so cannot be called simulateously, see ReadAt
 func (self *LazyChunkReader) Read(b []byte) (read int, err error) {
 	read, err = self.ReadAt(b, self.off)
-	// glog.V(logger.Detail).Infof("read: %v, off: %v, error: %v", read, self.off, err)
 
 	self.off += int64(read)
 	return
diff --git a/swarm/storage/chunker_test.go b/swarm/storage/chunker_test.go
index e6ca3d087..4f05cd1cc 100644
--- a/swarm/storage/chunker_test.go
+++ b/swarm/storage/chunker_test.go
@@ -18,6 +18,7 @@ package storage
 
 import (
 	"bytes"
+	"crypto/rand"
 	"encoding/binary"
 	"fmt"
 	"io"
@@ -27,6 +28,7 @@ import (
 	"time"
 )
 
+
 /*
 Tests TreeChunker by splitting and joining a random byte slice
 */
@@ -49,7 +51,7 @@ func (self *chunkerTester) checkChunks(t *testing.T, want int) {
 	}
 }
 
-func (self *chunkerTester) Split(chunker Splitter, data io.Reader, size int64, chunkC chan *Chunk, swg *sync.WaitGroup) (key Key) {
+func (self *chunkerTester) Split(chunker Splitter, data io.Reader, size int64, chunkC chan *Chunk, swg *sync.WaitGroup, expectedError error) (key Key) {
 	// reset
 	self.chunks = make(map[string]*Chunk)
 
@@ -65,14 +67,9 @@ func (self *chunkerTester) Split(chunker Splitter, data io.Reader, size int64, c
 				select {
 				case <-timeout:
 					self.t.Fatalf("Join timeout error")
-
-				case chunk, ok := <-chunkC:
-					if !ok {
-						// glog.V(logger.Info).Infof("chunkC closed quitting")
-						close(quitC)
-						return
-					}
-					// glog.V(logger.Info).Infof("chunk %v received", len(self.chunks))
+				case <-quitC:
+					return
+				case chunk := <-chunkC:
 					// self.chunks = append(self.chunks, chunk)
 					self.chunks[chunk.Key.String()] = chunk
 					if chunk.wg != nil {
@@ -83,21 +80,16 @@ func (self *chunkerTester) Split(chunker Splitter, data io.Reader, size int64, c
 		}()
 	}
 	key, err := chunker.Split(data, size, chunkC, swg, nil)
-	if err != nil {
+	if err != nil && expectedError == nil {
 		self.t.Fatalf("Split error: %v", err)
+	} else if expectedError != nil && (err == nil || err.Error() != expectedError.Error()) {
+		self.t.Fatalf("Not receiving the correct error! Expected %v, received %v", expectedError, err)
 	}
 	if chunkC != nil {
 		if swg != nil {
-			// glog.V(logger.Info).Infof("Waiting for storage to finish")
 			swg.Wait()
-			// glog.V(logger.Info).Infof("Storage finished")
 		}
-		close(chunkC)
-	}
-	if chunkC != nil {
-		// glog.V(logger.Info).Infof("waiting for splitter finished")
-		<-quitC
-		// glog.V(logger.Info).Infof("Splitter finished")
+		close(quitC)
 	}
 	return
 }
@@ -105,11 +97,9 @@ func (self *chunkerTester) Split(chunker Splitter, data io.Reader, size int64, c
 func (self *chunkerTester) Join(chunker Chunker, key Key, c int, chunkC chan *Chunk, quitC chan bool) LazySectionReader {
 	// reset but not the chunks
 
-	// glog.V(logger.Info).Infof("Splitter finished")
 	reader := chunker.Join(key, chunkC)
 
 	timeout := time.After(600 * time.Second)
-	// glog.V(logger.Info).Infof("Splitter finished")
 	i := 0
 	go func() {
 		for {
@@ -122,15 +112,12 @@ func (self *chunkerTester) Join(chunker Chunker, key Key, c int, chunkC chan *Ch
 					close(quitC)
 					return
 				}
-				// glog.V(logger.Info).Infof("chunk %v: %v", i, chunk.Key.String())
 				// this just mocks the behaviour of a chunk store retrieval
 				stored, success := self.chunks[chunk.Key.String()]
-				// glog.V(logger.Info).Infof("chunk %v, success: %v", chunk.Key.String(), success)
 				if !success {
 					self.t.Fatalf("not found")
 					return
 				}
-				// glog.V(logger.Info).Infof("chunk %v: %v", i, chunk.Key.String())
 				chunk.SData = stored.SData
 				chunk.Size = int64(binary.LittleEndian.Uint64(chunk.SData[0:8]))
 				close(chunk.C)
@@ -141,6 +128,26 @@ func (self *chunkerTester) Join(chunker Chunker, key Key, c int, chunkC chan *Ch
 	return reader
 }
 
+func testRandomBrokenData(splitter Splitter, n int, tester *chunkerTester) {
+	data := io.LimitReader(rand.Reader, int64(n))
+	brokendata := brokenLimitReader(data, n, n/2)
+
+	buf := make([]byte, n)
+	_, err := brokendata.Read(buf)
+	if err == nil || err.Error() != "Broken reader" {
+		tester.t.Fatalf("Broken reader is not broken, hence broken. Returns: %v", err)
+	}
+
+	data = io.LimitReader(rand.Reader, int64(n))
+	brokendata = brokenLimitReader(data, n, n/2)
+
+	chunkC := make(chan *Chunk, 1000)
+	swg := &sync.WaitGroup{}
+
+	key := tester.Split(splitter, brokendata, int64(n), chunkC, swg, fmt.Errorf("Broken reader"))
+	tester.t.Logf(" Key = %v\n", key)
+}
+
 func testRandomData(splitter Splitter, n int, tester *chunkerTester) {
 	if tester.inputs == nil {
 		tester.inputs = make(map[uint64][]byte)
@@ -151,13 +158,13 @@ func testRandomData(splitter Splitter, n int, tester *chunkerTester) {
 		data, input = testDataReaderAndSlice(n)
 		tester.inputs[uint64(n)] = input
 	} else {
-		data = limitReader(bytes.NewReader(input), n)
+		data = io.LimitReader(bytes.NewReader(input), int64(n))
 	}
 
 	chunkC := make(chan *Chunk, 1000)
 	swg := &sync.WaitGroup{}
 
-	key := tester.Split(splitter, data, int64(n), chunkC, swg)
+	key := tester.Split(splitter, data, int64(n), chunkC, swg, nil)
 	tester.t.Logf(" Key = %v\n", key)
 
 	chunkC = make(chan *Chunk, 1000)
@@ -166,9 +173,7 @@ func testRandomData(splitter Splitter, n int, tester *chunkerTester) {
 	chunker := NewTreeChunker(NewChunkerParams())
 	reader := tester.Join(chunker, key, 0, chunkC, quitC)
 	output := make([]byte, n)
-	// glog.V(logger.Info).Infof(" Key = %v\n", key)
 	r, err := reader.Read(output)
-	// glog.V(logger.Info).Infof(" read = %v  %v\n", r, err)
 	if r != n || err != io.EOF {
 		tester.t.Fatalf("read error  read: %v  n = %v  err = %v\n", r, n, err)
 	}
@@ -183,7 +188,7 @@ func testRandomData(splitter Splitter, n int, tester *chunkerTester) {
 
 func TestRandomData(t *testing.T) {
 	// sizes := []int{123456}
-	sizes := []int{1, 60, 83, 179, 253, 1024, 4095, 4096, 4097, 123456}
+	sizes := []int{1, 60, 83, 179, 253, 1024, 4095, 4096, 4097, 8191, 8192, 8193, 123456, 2345678}
 	tester := &chunkerTester{t: t}
 	chunker := NewTreeChunker(NewChunkerParams())
 	for _, s := range sizes {
@@ -195,6 +200,16 @@ func TestRandomData(t *testing.T) {
 	}
 }
 
+func TestRandomBrokenData(t *testing.T) {
+	sizes := []int{1, 60, 83, 179, 253, 1024, 4095, 4096, 4097, 8191, 8192, 8193, 123456, 2345678}
+	tester := &chunkerTester{t: t}
+	chunker := NewTreeChunker(NewChunkerParams())
+	for _, s := range sizes {
+		testRandomBrokenData(chunker, s, tester)
+		t.Logf("done size: %v", s)
+	}
+}
+
 func readAll(reader LazySectionReader, result []byte) {
 	size := int64(len(result))
 
@@ -227,7 +242,7 @@ func benchmarkJoin(n int, t *testing.B) {
 		chunkC := make(chan *Chunk, 1000)
 		swg := &sync.WaitGroup{}
 
-		key := tester.Split(chunker, data, int64(n), chunkC, swg)
+		key := tester.Split(chunker, data, int64(n), chunkC, swg, nil)
 		// t.StartTimer()
 		chunkC = make(chan *Chunk, 1000)
 		quitC := make(chan bool)
@@ -248,8 +263,7 @@ func benchmarkSplitTree(n int, t *testing.B) {
 		chunker := NewTreeChunker(NewChunkerParams())
 		tester := &chunkerTester{t: t}
 		data := testDataReader(n)
-		// glog.V(logger.Info).Infof("splitting data of length %v", n)
-		tester.Split(chunker, data, int64(n), nil, nil)
+		tester.Split(chunker, data, int64(n), nil, nil, nil)
 	}
 	stats := new(runtime.MemStats)
 	runtime.ReadMemStats(stats)
@@ -262,8 +276,7 @@ func benchmarkSplitPyramid(n int, t *testing.B) {
 		splitter := NewPyramidChunker(NewChunkerParams())
 		tester := &chunkerTester{t: t}
 		data := testDataReader(n)
-		// glog.V(logger.Info).Infof("splitting data of length %v", n)
-		tester.Split(splitter, data, int64(n), nil, nil)
+		tester.Split(splitter, data, int64(n), nil, nil, nil)
 	}
 	stats := new(runtime.MemStats)
 	runtime.ReadMemStats(stats)
diff --git a/swarm/storage/common_test.go b/swarm/storage/common_test.go
index e81a82b7b..889b28a70 100644
--- a/swarm/storage/common_test.go
+++ b/swarm/storage/common_test.go
@@ -19,6 +19,7 @@ package storage
 import (
 	"bytes"
 	"crypto/rand"
+	"fmt"
 	"io"
 	"sync"
 	"testing"
@@ -27,32 +28,31 @@ import (
 	"github.com/ethereum/go-ethereum/logger/glog"
 )
 
-type limitedReader struct {
-	r    io.Reader
-	off  int64
-	size int64
+type brokenLimitedReader struct {
+	lr    io.Reader
+	errAt int
+	off   int
+	size  int
 }
 
-func limitReader(r io.Reader, size int) *limitedReader {
-	return &limitedReader{r, 0, int64(size)}
-}
-
-func (self *limitedReader) Read(buf []byte) (int, error) {
-	limit := int64(len(buf))
-	left := self.size - self.off
-	if limit >= left {
-		limit = left
-	}
-	n, err := self.r.Read(buf[:limit])
-	if err == nil && limit == left {
-		err = io.EOF
+func brokenLimitReader(data io.Reader, size int, errAt int) *brokenLimitedReader {
+	return &brokenLimitedReader{
+		lr:    data,
+		errAt: errAt,
+		size:  size,
 	}
-	self.off += int64(n)
-	return n, err
 }
 
 func testDataReader(l int) (r io.Reader) {
-	return limitReader(rand.Reader, l)
+	return io.LimitReader(rand.Reader, int64(l))
+}
+
+func (self *brokenLimitedReader) Read(buf []byte) (int, error) {
+	if self.off+len(buf) > self.errAt {
+		return 0, fmt.Errorf("Broken reader")
+	}
+	self.off += len(buf)
+	return self.lr.Read(buf)
 }
 
 func testDataReaderAndSlice(l int) (r io.Reader, slice []byte) {
@@ -60,7 +60,7 @@ func testDataReaderAndSlice(l int) (r io.Reader, slice []byte) {
 	if _, err := rand.Read(slice); err != nil {
 		panic("rand error")
 	}
-	r = limitReader(bytes.NewReader(slice), l)
+	r = io.LimitReader(bytes.NewReader(slice), int64(l))
 	return
 }
 
diff --git a/swarm/storage/pyramid.go b/swarm/storage/pyramid.go
index 3c1ef17a0..79e1927b9 100644
--- a/swarm/storage/pyramid.go
+++ b/swarm/storage/pyramid.go
@@ -81,7 +81,6 @@ func (self *PyramidChunker) Split(data io.Reader, size int64, chunkC chan *Chunk
 
 	chunks := (size + self.chunkSize - 1) / self.chunkSize
 	depth := int(math.Ceil(math.Log(float64(chunks))/math.Log(float64(self.branches)))) + 1
-	// glog.V(logger.Detail).Infof("chunks: %v, depth: %v", chunks, depth)
 
 	results := Tree{
 		Chunks: chunks,
@@ -99,26 +98,24 @@ func (self *PyramidChunker) Split(data io.Reader, size int64, chunkC chan *Chunk
 		go self.processor(pend, swg, tasks, chunkC, &results)
 	}
 	// Feed the chunks into the task pool
+	read := 0
 	for index := 0; ; index++ {
 		buffer := make([]byte, self.chunkSize+8)
 		n, err := data.Read(buffer[8:])
-		last := err == io.ErrUnexpectedEOF || err == io.EOF
-		// glog.V(logger.Detail).Infof("n: %v, index: %v, depth: %v", n, index, depth)
+		read += n
+		last := int64(read) == size || err == io.ErrUnexpectedEOF || err == io.EOF
 		if err != nil && !last {
-			// glog.V(logger.Info).Infof("error: %v", err)
 			close(abortC)
 			break
 		}
 		binary.LittleEndian.PutUint64(buffer[:8], uint64(n))
 		pend.Add(1)
-		// glog.V(logger.Info).Infof("-> task %v (%v)", index, n)
 		select {
 		case tasks <- &Task{Index: int64(index), Size: uint64(n), Data: buffer[:n+8], Last: last}:
 		case <-abortC:
 			return nil, err
 		}
 		if last {
-			// glog.V(logger.Info).Infof("last task %v (%v)", index, n)
 			break
 		}
 	}
@@ -126,7 +123,6 @@ func (self *PyramidChunker) Split(data io.Reader, size int64, chunkC chan *Chunk
 	close(tasks)
 	pend.Wait()
 
-	// glog.V(logger.Info).Infof("len: %v", results.Levels[0][0])
 	key := results.Levels[0][0].Children[0][:]
 	return key, nil
 }
@@ -134,12 +130,10 @@ func (self *PyramidChunker) Split(data io.Reader, size int64, chunkC chan *Chunk
 func (self *PyramidChunker) processor(pend, swg *sync.WaitGroup, tasks chan *Task, chunkC chan *Chunk, results *Tree) {
 	defer pend.Done()
 
-	// glog.V(logger.Info).Infof("processor started")
 	// Start processing leaf chunks ad infinitum
 	hasher := self.hashFunc()
 	for task := range tasks {
 		depth, pow := len(results.Levels)-1, self.branches
-		// glog.V(logger.Info).Infof("task: %v, last: %v", task.Index, task.Last)
 		size := task.Size
 		data := task.Data
 		var node *Node
@@ -171,10 +165,8 @@ func (self *PyramidChunker) processor(pend, swg *sync.WaitGroup, tasks chan *Tas
 				}
 				node = &Node{pending, 0, make([]common.Hash, pending), last}
 				results.Levels[depth][task.Index/pow] = node
-				// glog.V(logger.Info).Infof("create node %v, %v (%v children, all pending)", depth, task.Index/pow, pending)
 			}
 			node.Pending--
-			// glog.V(logger.Info).Infof("pending now: %v", node.Pending)
 			i := task.Index / (pow / self.branches) % self.branches
 			if last {
 				node.Last = true
@@ -182,7 +174,6 @@ func (self *PyramidChunker) processor(pend, swg *sync.WaitGroup, tasks chan *Tas
 			copy(node.Children[i][:], hash)
 			node.Size += size
 			left := node.Pending
-			// glog.V(logger.Info).Infof("left pending now: %v, node size: %v", left, node.Size)
 			if chunkC != nil {
 				if swg != nil {
 					swg.Add(1)
@@ -198,7 +189,6 @@ func (self *PyramidChunker) processor(pend, swg *sync.WaitGroup, tasks chan *Tas
 
 			results.Lock.Unlock()
 			// If there's more work to be done, leave for others
-			// glog.V(logger.Info).Infof("left %v", left)
 			if left > 0 {
 				break
 			}