From 92a219e9c86c6ae775476bbe2b434059c73c47eb Mon Sep 17 00:00:00 2001
From: Antonio Navarro Perez <antnavper@gmail.com>
Date: Sun, 7 Jun 2020 12:52:00 +0200
Subject: [PATCH] Improve permissions, close files and lazy metadata loading.

Signed-off-by: Antonio Navarro Perez <antnavper@gmail.com>
---
 torrent/iio/utils.go     | 21 +++++++++++++++++++++
 torrent/mount/handler.go |  9 ++++++---
 torrent/node/file.go     | 22 +++++++---------------
 torrent/node/root.go     |  2 +-
 torrent/node/torrent.go  |  9 ++++++---
 torrent/node/zip.go      |  2 +-
 6 files changed, 42 insertions(+), 23 deletions(-)
 create mode 100644 torrent/iio/utils.go

diff --git a/torrent/iio/utils.go b/torrent/iio/utils.go
new file mode 100644
index 0000000..fa2bb59
--- /dev/null
+++ b/torrent/iio/utils.go
@@ -0,0 +1,21 @@
+package iio
+
+import (
+	"io"
+	"log"
+)
+
+func CloseIfCloseable(r interface{}) error {
+	log.Println("closing file...")
+	if r == nil {
+		return nil
+	}
+
+	closer, ok := r.(io.Closer)
+	if !ok {
+		log.Println("file is not implementing close method")
+		return nil
+	}
+
+	return closer.Close()
+}
diff --git a/torrent/mount/handler.go b/torrent/mount/handler.go
index 202c70b..863b42d 100644
--- a/torrent/mount/handler.go
+++ b/torrent/mount/handler.go
@@ -51,12 +51,15 @@ func (s *Handler) Mount(mpc *config.MountPoint) error {
 			return err
 		}
 
-		log.Println("getting torrent info", t.Name())
-		<-t.GotInfo()
+		// only get info if name is not available
+		if t.Name() == "" {
+			log.Println("getting torrent info", t.InfoHash())
+			<-t.GotInfo()
+		}
 
 		s.s.Add(mpc.Path, t)
+		log.Println("torrent added", t.Name())
 
-		log.Println("torrent info obtained", t.Name())
 		torrents = append(torrents, t)
 	}
 
diff --git a/torrent/node/file.go b/torrent/node/file.go
index 9adb6c9..2193eb3 100644
--- a/torrent/node/file.go
+++ b/torrent/node/file.go
@@ -7,6 +7,7 @@ import (
 	"math"
 	"syscall"
 
+	"github.com/ajnavarro/distribyted/iio"
 	"github.com/hanwen/go-fuse/v2/fs"
 	"github.com/hanwen/go-fuse/v2/fuse"
 )
@@ -14,7 +15,7 @@ import (
 var _ fs.NodeGetattrer = &File{}
 var _ fs.NodeOpener = &File{}
 var _ fs.NodeReader = &File{}
-var _ fs.NodeReleaser = &File{}
+var _ fs.NodeFlusher = &File{}
 
 // File is a fuse node for files inside a torrent
 type File struct {
@@ -44,7 +45,7 @@ func NewFileWithBlocks(readerFunc ReaderFunc, len int64, pieceLen int32, numPiec
 }
 
 func (tr *File) Getattr(ctx context.Context, f fs.FileHandle, out *fuse.AttrOut) syscall.Errno {
-	out.Mode = syscall.S_IFREG & 07777
+	out.Mode = syscall.S_IFREG & 0555
 	out.Nlink = 1
 	out.Size = uint64(tr.len)
 	if tr.pieceLen != 0 {
@@ -56,7 +57,6 @@ func (tr *File) Getattr(ctx context.Context, f fs.FileHandle, out *fuse.AttrOut)
 }
 
 func (tr *File) Open(ctx context.Context, flags uint32) (fh fs.FileHandle, fuseFlags uint32, errno syscall.Errno) {
-	// TODO use filehandle
 	if tr.r == nil {
 		r, err := tr.f()
 		if err != nil {
@@ -89,18 +89,10 @@ func (tr *File) Read(ctx context.Context, f fs.FileHandle, dest []byte, off int6
 	return fuse.ReadResultData(buf), fs.OK
 }
 
-func (tr *File) Release(ctx context.Context, f fs.FileHandle) syscall.Errno {
-	log.Println("closing file...")
-	if tr.r != nil {
-		closer, ok := tr.r.(io.Closer)
-		if ok {
-			if err := closer.Close(); err != nil {
-				log.Println("error closing file", err)
-				return syscall.EIO
-			}
-		} else {
-			log.Println("file is not implementing close method")
-		}
+func (tr *File) Flush(ctx context.Context, f fs.FileHandle) syscall.Errno {
+	if err := iio.CloseIfCloseable(tr.r); err != nil {
+		log.Println("error closing file", err)
+		return syscall.EIO
 	}
 
 	return fs.OK
diff --git a/torrent/node/root.go b/torrent/node/root.go
index eb40df9..afff936 100644
--- a/torrent/node/root.go
+++ b/torrent/node/root.go
@@ -33,7 +33,7 @@ func (root *Root) OnAdd(ctx context.Context) {
 }
 
 func (root *Root) Getattr(ctx context.Context, f fs.FileHandle, out *fuse.AttrOut) syscall.Errno {
-	out.Mode = syscall.S_IFDIR & 07777
+	out.Mode = syscall.S_IFDIR & 0555
 
 	return fs.OK
 }
diff --git a/torrent/node/torrent.go b/torrent/node/torrent.go
index 34bb562..5dd2c52 100644
--- a/torrent/node/torrent.go
+++ b/torrent/node/torrent.go
@@ -11,15 +11,17 @@ import (
 	"github.com/hanwen/go-fuse/v2/fuse"
 )
 
-var _ fs.NodeOnAdder = &Torrent{}
 var _ fs.NodeGetattrer = &Torrent{}
+var _ fs.NodeOpendirer = &Torrent{}
 
 type Torrent struct {
 	fs.Inode
 	t *torrent.Torrent
 }
 
-func (folder *Torrent) OnAdd(ctx context.Context) {
+func (folder *Torrent) Opendir(ctx context.Context) syscall.Errno {
+	<-folder.t.GotInfo()
+
 	for _, file := range folder.t.Files() {
 		file := file
 		LoadNodeByPath(
@@ -32,10 +34,11 @@ func (folder *Torrent) OnAdd(ctx context.Context) {
 			int64(file.Torrent().Info().NumPieces()),
 		)
 	}
+	return fs.OK
 }
 
 func (folder *Torrent) Getattr(ctx context.Context, f fs.FileHandle, out *fuse.AttrOut) syscall.Errno {
-	out.Mode = syscall.S_IFDIR & 07777
+	out.Mode = syscall.S_IFDIR & 0555
 
 	return fs.OK
 }
diff --git a/torrent/node/zip.go b/torrent/node/zip.go
index 37dcef2..2ffabbf 100644
--- a/torrent/node/zip.go
+++ b/torrent/node/zip.go
@@ -74,7 +74,7 @@ func (z *Zip) Opendir(ctx context.Context) syscall.Errno {
 }
 
 func (z *Zip) Getattr(ctx context.Context, f fs.FileHandle, out *fuse.AttrOut) syscall.Errno {
-	out.Mode = syscall.S_IFDIR & 07777
+	out.Mode = syscall.S_IFDIR & 0555
 	out.Size = uint64(z.size)
 
 	return fs.OK