From: Matt Joiner <anacrolix@gmail.com>
Date: Fri, 5 Feb 2016 04:45:32 +0000 (+1100)
Subject: Use missinggo.bitmap for tracking dirty chunks
X-Git-Tag: v1.0.0~916
X-Git-Url: http://www.git.stargrave.org/?a=commitdiff_plain;h=1b8bc1498cb6cf54eab620ec4958b80f89f8ab61;p=btrtrc.git

Use missinggo.bitmap for tracking dirty chunks
---

diff --git a/piece.go b/piece.go
index a56225c1..9f22d718 100644
--- a/piece.go
+++ b/piece.go
@@ -4,6 +4,7 @@ import (
 	"math/rand"
 	"sync"
 
+	"github.com/anacrolix/missinggo/bitmap"
 	"github.com/bradfitz/iter"
 
 	pp "github.com/anacrolix/torrent/peer_protocol"
@@ -32,7 +33,7 @@ type piece struct {
 	Hash pieceSum
 	// Chunks we've written to since the last check. The chunk offset and
 	// length can be determined by the request chunkSize in use.
-	DirtyChunks      []bool
+	DirtyChunks      bitmap.Bitmap
 	Hashing          bool
 	QueuedForHash    bool
 	EverHashed       bool
@@ -44,44 +45,28 @@ type piece struct {
 	noPendingWrites    sync.Cond
 }
 
+func (p *piece) pendingChunkIndex(chunkIndex int) bool {
+	return !p.DirtyChunks.Contains(chunkIndex)
+}
+
 func (p *piece) pendingChunk(cs chunkSpec, chunkSize pp.Integer) bool {
-	ci := chunkIndex(cs, chunkSize)
-	if ci >= len(p.DirtyChunks) {
-		return true
-	}
-	return !p.DirtyChunks[ci]
+	return p.pendingChunkIndex(chunkIndex(cs, chunkSize))
 }
 
 func (p *piece) hasDirtyChunks() bool {
-	for _, dirty := range p.DirtyChunks {
-		if dirty {
-			return true
-		}
-	}
-	return false
+	return p.DirtyChunks.Len() != 0
 }
 
 func (p *piece) numDirtyChunks() (ret int) {
-	for _, dirty := range p.DirtyChunks {
-		if dirty {
-			ret++
-		}
-	}
-	return
+	return p.DirtyChunks.Len()
 }
 
 func (p *piece) unpendChunkIndex(i int) {
-	for i >= len(p.DirtyChunks) {
-		p.DirtyChunks = append(p.DirtyChunks, false)
-	}
-	p.DirtyChunks[i] = true
+	p.DirtyChunks.Add(i)
 }
 
 func (p *piece) pendChunkIndex(i int) {
-	if i >= len(p.DirtyChunks) {
-		return
-	}
-	p.DirtyChunks[i] = false
+	p.DirtyChunks.Remove(i)
 }
 
 func chunkIndexSpec(index int, pieceLength, chunkSize pp.Integer) chunkSpec {
@@ -102,7 +87,7 @@ func (p *piece) shuffledPendingChunkSpecs(t *torrent, piece int) (css []chunkSpe
 	}
 	css = make([]chunkSpec, 0, numPending)
 	for ci := range iter.N(t.pieceNumChunks(piece)) {
-		if ci >= len(p.DirtyChunks) || !p.DirtyChunks[ci] {
+		if !p.DirtyChunks.Contains(ci) {
 			css = append(css, t.chunkIndexSpec(ci, piece))
 		}
 	}
diff --git a/torrent.go b/torrent.go
index 987b5b8f..f58a5d68 100644
--- a/torrent.go
+++ b/torrent.go
@@ -38,11 +38,13 @@ func (t *torrent) pieceNumPendingBytes(index int) (count pp.Integer) {
 	if !piece.EverHashed {
 		return
 	}
-	for i, dirty := range piece.DirtyChunks {
-		if dirty {
-			count -= t.chunkIndexSpec(i, index).Length
-		}
+	regularDirty := piece.numDirtyChunks()
+	lastChunkIndex := t.pieceNumChunks(index) - 1
+	if piece.pendingChunkIndex(lastChunkIndex) {
+		regularDirty--
+		count -= t.chunkIndexSpec(lastChunkIndex, index).Length
 	}
+	count -= pp.Integer(regularDirty) * t.chunkSize
 	return
 }
 
@@ -633,7 +635,7 @@ func (t *torrent) pieceNumChunks(piece int) int {
 }
 
 func (t *torrent) pendAllChunkSpecs(pieceIndex int) {
-	t.Pieces[pieceIndex].DirtyChunks = nil
+	t.Pieces[pieceIndex].DirtyChunks.Clear()
 }
 
 type Peer struct {
@@ -826,16 +828,7 @@ func (t *torrent) pieceNumPendingChunks(piece int) int {
 }
 
 func (t *torrent) pieceAllDirty(piece int) bool {
-	p := &t.Pieces[piece]
-	if len(p.DirtyChunks) != t.pieceNumChunks(piece) {
-		return false
-	}
-	for _, dirty := range p.DirtyChunks {
-		if !dirty {
-			return false
-		}
-	}
-	return true
+	return t.Pieces[piece].DirtyChunks.Len() == t.pieceNumChunks(piece)
 }
 
 func (t *torrent) forUrgentPieces(f func(piece int) (again bool)) (all bool) {