From: Matt Joiner <anacrolix@gmail.com>
Date: Sat, 9 Mar 2024 23:29:05 +0000 (+1100)
Subject: Add PrefixDeleter support to ResourcePieces storage
X-Git-Url: http://www.git.stargrave.org/?a=commitdiff_plain;h=d94913809e40bea0dfdcb1d7bde4c1a9cc8eb95f;p=btrtrc.git

Add PrefixDeleter support to ResourcePieces storage
---

diff --git a/go.mod b/go.mod
index 1af03a6e..51402c25 100644
--- a/go.mod
+++ b/go.mod
@@ -18,7 +18,7 @@ require (
 	github.com/anacrolix/missinggo/perf v1.0.0
 	github.com/anacrolix/missinggo/v2 v2.7.3
 	github.com/anacrolix/multiless v0.3.0
-	github.com/anacrolix/possum/go v0.0.0-20240222034319-2fe0737d4315
+	github.com/anacrolix/possum/go v0.1.1-0.20240309232535-7d660fa365f8
 	github.com/anacrolix/squirrel v0.6.0
 	github.com/anacrolix/sync v0.5.1
 	github.com/anacrolix/tagflag v1.3.0
diff --git a/go.sum b/go.sum
index fb5f86b1..0834ba1b 100644
--- a/go.sum
+++ b/go.sum
@@ -107,8 +107,8 @@ github.com/anacrolix/mmsg v1.0.0 h1:btC7YLjOn29aTUAExJiVUhQOuf/8rhm+/nWCMAnL3Hg=
 github.com/anacrolix/mmsg v1.0.0/go.mod h1:x8kRaJY/dCrY9Al0PEcj1mb/uFHwP6GCJ9fLl4thEPc=
 github.com/anacrolix/multiless v0.3.0 h1:5Bu0DZncjE4e06b9r1Ap2tUY4Au0NToBP5RpuEngSis=
 github.com/anacrolix/multiless v0.3.0/go.mod h1:TrCLEZfIDbMVfLoQt5tOoiBS/uq4y8+ojuEVVvTNPX4=
-github.com/anacrolix/possum/go v0.0.0-20240222034319-2fe0737d4315 h1:bwdpi8LWvEHrNgsu44SKmCzLeZ5iEH4rwmNafDdRHJ4=
-github.com/anacrolix/possum/go v0.0.0-20240222034319-2fe0737d4315/go.mod h1:pw5HEMBSiL+otYzHe4q5jGaVuy5unl+Mt4Bx6SDemW8=
+github.com/anacrolix/possum/go v0.1.1-0.20240309232535-7d660fa365f8 h1:XDKUI9RHyhyfGXVXb/4N+l5kGo5jQITrrbF7EZPLuak=
+github.com/anacrolix/possum/go v0.1.1-0.20240309232535-7d660fa365f8/go.mod h1:pw5HEMBSiL+otYzHe4q5jGaVuy5unl+Mt4Bx6SDemW8=
 github.com/anacrolix/squirrel v0.6.0 h1:ovfWW42wcGzrVYYI9s56pEYzfeTwtXxCCvSd+KwvUEA=
 github.com/anacrolix/squirrel v0.6.0/go.mod h1:60vdNPUbK1jYWePp39Wqn9whHm12Yb9JEuwOXzLMDuY=
 github.com/anacrolix/stm v0.2.0/go.mod h1:zoVQRvSiGjGoTmbM0vSLIiaKjWtNPeTvXUSdJQA4hsg=
diff --git a/storage/issue96_test.go b/storage/issue96_test.go
index 1be98aa5..d9857881 100644
--- a/storage/issue96_test.go
+++ b/storage/issue96_test.go
@@ -1,9 +1,9 @@
 package storage
 
 import (
-	g "github.com/anacrolix/generics"
 	"testing"
 
+	g "github.com/anacrolix/generics"
 	"github.com/stretchr/testify/require"
 
 	"github.com/anacrolix/torrent/metainfo"
diff --git a/storage/piece-resource.go b/storage/piece-resource.go
index 94325027..1b0ae236 100644
--- a/storage/piece-resource.go
+++ b/storage/piece-resource.go
@@ -75,6 +75,10 @@ type ConsecutiveChunkReader interface {
 	ReadConsecutiveChunks(prefix string) (io.ReadCloser, error)
 }
 
+type PrefixDeleter interface {
+	DeletePrefix(prefix string) error
+}
+
 type piecePerResourcePiece struct {
 	mp metainfo.Piece
 	// The piece hash if we have it. It could be 20 or 32 bytes depending on the info version.
@@ -140,7 +144,7 @@ type SizedPutter interface {
 	PutSized(io.Reader, int64) error
 }
 
-func (s piecePerResourcePiece) MarkComplete() error {
+func (s piecePerResourcePiece) MarkComplete() (err error) {
 	s.mu.Lock()
 	defer s.mu.Unlock()
 	incompleteChunks := s.getChunks()
@@ -162,11 +166,20 @@ func (s piecePerResourcePiece) MarkComplete() error {
 			return completedInstance.Put(r)
 		}
 	}()
-	if err == nil && !s.opts.LeaveIncompleteChunks {
-		// I think we do this synchronously here since we don't want callers to act on the completed
-		// piece if we're concurrently still deleting chunks. The caller may decide to start
-		// downloading chunks again and won't expect us to delete them. It seems to be much faster
-		// to let the resource provider do this if possible.
+	if err != nil || s.opts.LeaveIncompleteChunks {
+		return
+	}
+
+	// I think we do this synchronously here since we don't want callers to act on the completed
+	// piece if we're concurrently still deleting chunks. The caller may decide to start
+	// downloading chunks again and won't expect us to delete them. It seems to be much faster
+	// to let the resource provider do this if possible.
+	if pd, ok := s.rp.(PrefixDeleter); ok {
+		err = pd.DeletePrefix(s.incompleteDirPath() + "/")
+		if err != nil {
+			err = fmt.Errorf("deleting incomplete prefix: %w", err)
+		}
+	} else {
 		var wg sync.WaitGroup
 		for _, c := range incompleteChunks {
 			wg.Add(1)
diff --git a/storage/possum/possum_test.go b/storage/possum/possum_test.go
index 1c0e8110..3abefd49 100644
--- a/storage/possum/possum_test.go
+++ b/storage/possum/possum_test.go
@@ -28,5 +28,11 @@ func BenchmarkProvider(b *testing.B) {
 	clientStorageImpl := storage.NewResourcePiecesOpts(
 		possumTorrentProvider,
 		storage.ResourcePiecesOpts{LeaveIncompleteChunks: true})
-	test_storage.BenchmarkPieceMarkComplete(b, clientStorageImpl, test_storage.DefaultPieceSize, test_storage.DefaultNumPieces, 0)
+	test_storage.BenchmarkPieceMarkComplete(
+		b,
+		clientStorageImpl,
+		test_storage.DefaultPieceSize,
+		test_storage.DefaultNumPieces,
+		0,
+	)
 }