Have Read() return Status separately.

fuse/api.go

@@ -161,7 +161,7 @@ type File interface {
 	// the inner file here.
 	InnerFile() File
 
-	Read(dest []byte, off int64) ReadResult
+	Read(dest []byte, off int64) (ReadResult, Status)
 	Write(data []byte, off int64) (written uint32, code Status)
 	Flush() Status
 	Release()
@@ -281,7 +281,7 @@ type RawFileSystem interface {
 	// File handling.
 	Create(out *raw.CreateOut, header *raw.InHeader, input *raw.CreateIn, name string) (code Status)
 	Open(out *raw.OpenOut, header *raw.InHeader, input *raw.OpenIn) (status Status)
-	Read(*raw.InHeader, *raw.ReadIn, []byte) ReadResult
+	Read(*raw.InHeader, *raw.ReadIn, []byte) (ReadResult, Status)
 
 	Release(header *raw.InHeader, input *raw.ReleaseIn)
 	Write(*raw.InHeader, *raw.WriteIn, []byte) (written uint32, code Status)

fuse/copy.go

@@ -27,9 +27,9 @@ func CopyFile(srcFs, destFs FileSystem, srcFile, destFile string, context *Conte
 	buf := make([]byte, 128*(1<<10))
 	off := int64(0)
 	for {
-		res := src.Read(buf, off)
-		if !res.Ok() {
-			return res.Status
+		res, code := src.Read(buf, off)
+		if !code.Ok() {
+			return code
 		}
 		res.Read(buf)
 

fuse/defaultfile.go

@@ -21,8 +21,8 @@ func (f *DefaultFile) String() string {
 	return "DefaultFile"
 }
 
-func (f *DefaultFile) Read(buf []byte, off int64) ReadResult {
-	return ReadResult{Status: ENOSYS}
+func (f *DefaultFile) Read(buf []byte, off int64) (ReadResult, Status) {
+	return ReadResult{}, ENOSYS
 }
 
 func (f *DefaultFile) Write(data []byte, off int64) (uint32, Status) {

fuse/defaultraw.go

@@ -96,8 +96,8 @@ func (fs *DefaultRawFileSystem) OpenDir(out *raw.OpenOut, header *raw.InHeader,
 	return ENOSYS
 }
 
-func (fs *DefaultRawFileSystem) Read(header *raw.InHeader, input *raw.ReadIn, buf []byte) ReadResult {
-	return ReadResult{}
+func (fs *DefaultRawFileSystem) Read(header *raw.InHeader, input *raw.ReadIn, buf []byte) (ReadResult, Status) {
+	return ReadResult{}, ENOSYS
 }
 
 func (fs *DefaultRawFileSystem) Release(header *raw.InHeader, input *raw.ReleaseIn) {

fuse/files.go

@@ -39,15 +39,14 @@ func NewDataFile(data []byte) *DataFile {
 	return f
 }
 
-func (f *DataFile) Read(buf []byte, off int64) (res ReadResult) {
+func (f *DataFile) Read(buf []byte, off int64) (res ReadResult, code Status) {
 	end := int(off) + int(len(buf))
 	if end > len(f.data) {
 		end = len(f.data)
 	}
 
 	res.Data = f.data[off:end]
-	res.Status = OK
-	return res
+	return res, OK
 }
 
 ////////////////
@@ -67,8 +66,8 @@ func (f *DevNullFile) String() string {
 	return "DevNullFile"
 }
 
-func (f *DevNullFile) Read(buf []byte, off int64) ReadResult {
-	return ReadResult{}
+func (f *DevNullFile) Read(buf []byte, off int64) (ReadResult, Status) {
+	return ReadResult{}, OK
 }
 
 func (f *DevNullFile) Write(content []byte, off int64) (uint32, Status) {
@@ -100,13 +99,12 @@ func (f *LoopbackFile) String() string {
 	return fmt.Sprintf("LoopbackFile(%s)", f.File.Name())
 }
 
-func (f *LoopbackFile) Read(buf []byte, off int64) (res ReadResult) {
+func (f *LoopbackFile) Read(buf []byte, off int64) (res ReadResult, code Status) {
 	return ReadResult{
 		Fd:     f.File.Fd(),
 		FdOff:  off,
 		FdSize: len(buf),
-		Status: OK,
-	}
+	}, OK
 }
 
 func (f *LoopbackFile) Write(data []byte, off int64) (uint32, Status) {

fuse/fsetattr_test.go

@@ -22,13 +22,13 @@ func (f *MutableDataFile) String() string {
 	return "MutableDataFile"
 }
 
-func (f *MutableDataFile) Read(buf []byte, off int64) ReadResult {
+func (f *MutableDataFile) Read(buf []byte, off int64) (ReadResult, Status) {
 	end := int(off)+len(buf)
 	if end > len(f.data) {
 		end = len(f.data)
 	}
 	
-	return ReadResult{Data: f.data[off:end]}
+	return ReadResult{Data: f.data[off:end]}, OK
 }
 
 func (f *MutableDataFile) Write(d []byte, off int64) (uint32, Status) {

fuse/fsops.go

@@ -350,7 +350,7 @@ func (c *FileSystemConnector) Write(header *raw.InHeader, input *raw.WriteIn, da
 	return opened.WithFlags.File.Write(data, int64(input.Offset))
 }
 
-func (c *FileSystemConnector) Read(header *raw.InHeader, input *raw.ReadIn, buf []byte) ReadResult {
+func (c *FileSystemConnector) Read(header *raw.InHeader, input *raw.ReadIn, buf []byte) (ReadResult, Status) {
 	node := c.toInode(header.NodeId)
 	opened := node.mount.getOpenedFile(input.Fh)
 

fuse/lockingfs.go

@@ -16,6 +16,8 @@ type LockingFileSystem struct {
 	lock sync.Mutex
 }
 
+var _ = ((FileSystem)((*LockingFileSystem)(nil)))
+
 func NewLockingFileSystem(pfs FileSystem) *LockingFileSystem {
 	l := new(LockingFileSystem)
 	l.FileSystem = pfs
@@ -276,7 +278,7 @@ func (fs *LockingRawFileSystem) ReleaseDir(header *raw.InHeader, h *raw.ReleaseI
 	fs.RawFileSystem.ReleaseDir(header, h)
 }
 
-func (fs *LockingRawFileSystem) Read(header *raw.InHeader, input *raw.ReadIn, buf []byte) ReadResult {
+func (fs *LockingRawFileSystem) Read(header *raw.InHeader, input *raw.ReadIn, buf []byte) (ReadResult, Status) {
 	defer fs.locked()()
 	return fs.RawFileSystem.Read(header, input, buf)
 }

fuse/opcode.go

@@ -269,9 +269,7 @@ func doLink(state *MountState, req *request) {
 func doRead(state *MountState, req *request) {
 	in := (*raw.ReadIn)(req.inData)
 	buf := state.AllocOut(req, in.Size)
-	res := state.fileSystem.Read(req.inHeader, in, buf)
-	req.flatData = res
-	req.status = res.Status
+	req.flatData, req.status = state.fileSystem.Read(req.inHeader, in, buf)
 }
 
 func doFlush(state *MountState, req *request) {

fuse/read.go

@@ -14,9 +14,6 @@ import (
 // If at any point,  the raw data is needed, ReadResult.Read() will
 // load the raw data into the Data member.
 type ReadResult struct {
-	// Errno code for the read.
-	Status
-
 	// Raw bytes for the read.
 	Data []byte
 
@@ -46,11 +43,10 @@ func (r *ReadResult) Size() int {
 // Reads raw bytes from file descriptor if necessary, using the passed
 // buffer as storage.
 func (r *ReadResult) Read(buf []byte) Status {
-	if r.Data != nil || !r.Ok() {
-		return r.Status
+	if r.Data != nil {
+		return OK
 	}
 	if len(buf) < r.FdSize {
-		r.Status = ERANGE
 		return ERANGE
 	}
 
@@ -58,13 +54,13 @@ func (r *ReadResult) Read(buf []byte) Status {
 	if err == io.EOF {
 		err = nil
 	}
-	r.Status = ToStatus(err)
-	if r.Ok() {
+	code := ToStatus(err)
+	if code.Ok() {
 		r.Data = buf[:n]
 	}
 	r.Fd = 0
 	r.FdOff = 0
 	r.FdSize = 0
 
-	return r.Status
+	return code
 }