From: Matt Joiner <anacrolix@gmail.com>
Date: Mon, 16 May 2016 08:44:58 +0000 (+1000)
Subject: Add piece-per-resource storage
X-Git-Tag: v1.0.0~729
X-Git-Url: http://www.git.stargrave.org/?a=commitdiff_plain;h=61e43f4261cd9f6a794d608c77c1bffbf785278f;p=btrtrc.git

Add piece-per-resource storage
---

diff --git a/storage/piece_resource.go b/storage/piece_resource.go
new file mode 100644
index 00000000..2f6d6eef
--- /dev/null
+++ b/storage/piece_resource.go
@@ -0,0 +1,80 @@
+package storage
+
+import (
+	"io"
+	"path"
+
+	"github.com/anacrolix/missinggo"
+	"github.com/anacrolix/missinggo/uniform"
+
+	"github.com/anacrolix/torrent/metainfo"
+)
+
+type piecePerResource struct {
+	p uniform.Provider
+}
+
+func NewPiecePerResource(p uniform.Provider) I {
+	return &piecePerResource{
+		p: p,
+	}
+}
+
+func (s *piecePerResource) OpenTorrent(info *metainfo.InfoEx) (Torrent, error) {
+	return s, nil
+}
+
+func (s *piecePerResource) Close() error {
+	return nil
+}
+
+func (s *piecePerResource) Piece(p metainfo.Piece) Piece {
+	completed, err := s.p.NewResource(path.Join("completed", p.Hash().HexString()))
+	if err != nil {
+		panic(err)
+	}
+	incomplete, err := s.p.NewResource(path.Join("incomplete", p.Hash().HexString()))
+	if err != nil {
+		panic(err)
+	}
+	return piecePerResourcePiece{
+		p: p,
+		c: completed,
+		i: incomplete,
+	}
+}
+
+type piecePerResourcePiece struct {
+	p metainfo.Piece
+	c uniform.Resource
+	i uniform.Resource
+}
+
+func (s piecePerResourcePiece) GetIsComplete() bool {
+	fi, err := s.c.Stat()
+	return err == nil && fi.Size() == s.p.Length()
+}
+
+func (s piecePerResourcePiece) MarkComplete() error {
+	return uniform.Move(s.i, s.c)
+}
+
+func (s piecePerResourcePiece) ReadAt(b []byte, off int64) (n int, err error) {
+	missinggo.LimitLen(&b, s.p.Length()-off)
+	n, err = s.c.ReadAt(b, off)
+	if err != nil {
+		n, err = s.i.ReadAt(b, off)
+	}
+	off += int64(n)
+	if off >= s.p.Length() {
+		err = io.EOF
+	} else if err == io.EOF {
+		err = io.ErrUnexpectedEOF
+	}
+	return
+}
+
+func (s piecePerResourcePiece) WriteAt(b []byte, off int64) (n int, err error) {
+	missinggo.LimitLen(&b, s.p.Length()-off)
+	return s.i.WriteAt(b, off)
+}