lib9p

commit 48cd056e2a840f80b01fbc881b518df2b49fbef6
parent 5023b5ec4b4cac943383d99a13e853672fbf23d8
Author: Matsuda Kenji <info@mtkn.jp>
Date:   Sun, 24 Dec 2023 12:25:05 +0900

add support for the n argument of client.(*File).ReadDir

Diffstat:
M
client/file.go
 | 
49
+++++++++++++++++++++++++++++++++----------------
M
client/fs.go
 | 
2
+-
M
diskfs/stat_unix.go
 | 
2
+-

3 files changed, 35 insertions(+), 18 deletions(-)
diff --git a/client/file.go b/client/file.go
@@ -17,6 +17,7 @@ type File struct {
 	qid    lib9p.Qid
 	iounit uint32
 	fs     *FS
+	dirBuf []fs.DirEntry
 }
 
 func (cf *File) Stat() (fs.FileInfo, error) {
@@ -88,7 +89,6 @@ func (cf *File) Read(b []byte) (int, error) {
 	}
 }
 
-// TODO: support n
 func (cf *File) ReadDir(n int) ([]fs.DirEntry, error) {
 	if cf.qid.Type&lib9p.QTDIR == 0 {
 		return nil, errors.New("not a directory")
@@ -96,21 +96,38 @@ func (cf *File) ReadDir(n int) ([]fs.DirEntry, error) {
 	if cf.fid.omode == -1 {
 		return nil, errors.New("not open")
 	}
-	tag, err := cf.fs.tPool.add()
-	if err != nil {
-		return nil, err
-	}
-	data, err := cf.fs.c.Read(context.TODO(), tag, cf.fid.fid, cf.fid.offset, cf.iounit)
-	cf.fs.tPool.delete(tag)
-	if err != nil {
-		return nil, err
+	var (
+		de []fs.DirEntry
+		err error
+		data []byte
+		tag uint16
+	)
+	for n <= 0 || len(cf.dirBuf) < n {
+		tag, err = cf.fs.tPool.add()
+		if err != nil {
+			break
+		}
+		data, err = cf.fs.c.Read(context.TODO(), tag, cf.fid.fid, cf.fid.offset, cf.iounit)
+		cf.fs.tPool.delete(tag)
+		if err != nil {
+			break
+		} else if len(data) == 0 {
+			err = io.EOF
+			break
+		}
+		cf.fid.offset += uint64(len(data))
+		for len(data) > 0 {
+			st := lib9p.NewStat(data)
+			data = data[2+st.Size():]
+			cf.dirBuf = append(cf.dirBuf, &lib9p.FileInfo{Stat: *st})
+		}
 	}
-	cf.fid.offset += uint64(len(data))
-	var de []fs.DirEntry
-	for len(data) > 0 {
-		st := lib9p.NewStat(data)
-		data = data[2+st.Size():]
-		de = append(de, &lib9p.FileInfo{Stat: *st})
+	if 0 < n && n <= len(cf.dirBuf) {
+		de = cf.dirBuf[:n]
+		cf.dirBuf = cf.dirBuf[n:]
+	} else {
+		de = cf.dirBuf
+		cf.dirBuf = nil
 	}
-	return de, nil
+	return de, err
 }
diff --git a/client/fs.go b/client/fs.go
@@ -50,7 +50,7 @@ func (fsys *FS) OpenFile(name string, omode lib9p.OpenMode) (lib9p.File, error) 
 	return f, nil
 }
 
-// walkFile walks the file system to the named file name and
+// walkFile walks the file system to the file named name and
 // returns the corresponding file.
 // returned file is not open.
 func (fsys *FS) walkFile(name string) (*File, error) {
diff --git a/diskfs/stat_unix.go b/diskfs/stat_unix.go
@@ -89,7 +89,7 @@ func (f *File) wstat(s *lib9p.Stat) error {
 	}
 	oldStat := fi.Sys().(*lib9p.Stat)
 	if s.Length != oldStat.Length {
-		if file == nil {
+		if file == nil { // TODO: what is this?
 			file, err = os.OpenFile(path.Join(f.fs.rootPath, f.path), os.O_RDWR, 0)
 			if err != nil {
 				return err