nodefs: streaming directory reads

compile on darwin too

nodefs/api.go

@@ -79,25 +79,6 @@ type DirStream interface {
 	Close()
 }
 
-// XXX names
-type DirArray struct {
-	Entries []fuse.DirEntry
-}
-
-func (a *DirArray) HasNext() bool {
-	return len(a.Entries) > 0
-}
-
-func (a *DirArray) Next() (fuse.DirEntry, fuse.Status) {
-	e := a.Entries[0]
-	a.Entries = a.Entries[1:]
-	return e, fuse.OK
-}
-
-func (a *DirArray) Close() {
-
-}
-
 /*
 NOSUBMIT: how to structure?
 

nodefs/dirstream_darwin.go

+// Copyright 2019 the Go-FUSE Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package nodefs
+
+import (
+	"io"
+	"os"
+
+	"github.com/hanwen/go-fuse/fuse"
+)
+
+// XXX names
+type dirArray struct {
+	Entries []fuse.DirEntry
+}
+
+func (a *dirArray) HasNext() bool {
+	return len(a.Entries) > 0
+}
+
+func (a *dirArray) Next() (fuse.DirEntry, fuse.Status) {
+	e := a.Entries[0]
+	a.Entries = a.Entries[1:]
+	return e, fuse.OK
+}
+
+func (a *dirArray) Close() {
+
+}
+
+func NewLoopbackDirStream(nm string) (DirStream, fuse.Status) {
+	// XXX should implement streaming read to make sure the API works.
+	f, err := os.Open(nm)
+	if err != nil {
+		return nil, fuse.ToStatus(err)
+	}
+	defer f.Close()
+
+	var entries []fuse.DirEntry
+	for {
+		want := 100
+		infos, err := f.Readdir(want)
+		for _, info := range infos {
+			s := fuse.ToStatT(info)
+			if s == nil {
+				continue
+			}
+
+			entries = append(entries, fuse.DirEntry{
+				Name: info.Name(),
+				Mode: uint32(s.Mode),
+				Ino:  s.Ino,
+			})
+		}
+		if len(infos) < want || err == io.EOF {
+			break
+		}
+
+		if err != nil {
+			return nil, fuse.ToStatus(err)
+		}
+	}
+
+	return &dirArray{entries}, fuse.OK
+}

nodefs/dirstream_linux.go

+// Copyright 2019 the Go-FUSE Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package nodefs
+
+import (
+	"syscall"
+	"unsafe"
+
+	"github.com/hanwen/go-fuse/fuse"
+)
+
+type loopbackDirStream struct {
+	buf  []byte
+	todo []byte
+	fd   int
+}
+
+func NewLoopbackDirStream(name string) (DirStream, fuse.Status) {
+	fd, err := syscall.Open(name, syscall.O_DIRECTORY, 0755)
+	if err != nil {
+		return nil, fuse.ToStatus(err)
+	}
+
+	ds := &loopbackDirStream{
+		buf: make([]byte, 4096),
+		fd:  fd,
+	}
+
+	if err := ds.load(); !err.Ok() {
+		ds.Close()
+		return nil, err
+	}
+	return ds, fuse.OK
+}
+
+func (ds *loopbackDirStream) Close() {
+	syscall.Close(ds.fd)
+}
+
+func (ds *loopbackDirStream) HasNext() bool {
+	return len(ds.todo) > 0
+}
+
+func (ds *loopbackDirStream) Next() (fuse.DirEntry, fuse.Status) {
+	de := (*syscall.Dirent)(unsafe.Pointer(&ds.todo[0]))
+
+	nameBytes := ds.todo[unsafe.Offsetof(syscall.Dirent{}.Name):de.Reclen]
+	ds.todo = ds.todo[de.Reclen:]
+
+	for l := len(nameBytes); l > 0; l-- {
+		if nameBytes[l-1] != 0 {
+			break
+		}
+		nameBytes = nameBytes[:l-1]
+	}
+	result := fuse.DirEntry{
+		Ino:  de.Ino,
+		Mode: (uint32(de.Type) << 12),
+		Name: string(nameBytes),
+	}
+	return result, ds.load()
+}
+
+func (ds *loopbackDirStream) load() fuse.Status {
+	if len(ds.todo) > 0 {
+		return fuse.OK
+	}
+
+	n, err := syscall.Getdents(ds.fd, ds.buf)
+	if err != nil {
+		return fuse.ToStatus(err)
+	}
+	ds.todo = ds.buf[:n]
+	return fuse.OK
+}

nodefs/files_darwin.go

+// Copyright 2019 the Go-FUSE Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package nodefs
+
+import (
+	"context"
+	"time"
+
+	"github.com/hanwen/go-fuse/fuse"
+)
+
+// XXX fill out here.
+
+func (f *loopbackFile) Allocate(ctx context.Context, off uint64, sz uint64, mode uint32) fuse.Status {
+	return fuse.ENOSYS
+}
+
+func (f *loopbackFile) Utimens(ctx context.Context, a *time.Time, m *time.Time) fuse.Status {
+	return fuse.ENOSYS
+}

nodefs/loopback.go

@@ -6,7 +6,6 @@ package nodefs
 
 import (
 	"context"
-	"io"
 	"log"
 	"os"
 	"path/filepath"
@@ -181,7 +180,7 @@ func (n *loopbackNode) Create(ctx context.Context, name string, flags uint32, mo
 	}
 
 	node := n.rootNode.newLoopbackNode()
-	ch := n.inode().NewInode(node, st.Mode, idFromStat(&st))
+	ch := n.inode().NewInode(node, uint32(st.Mode), idFromStat(&st))
 	lf := newLoopbackFile(f)
 	n.mu.Lock()
 	defer n.mu.Unlock()
@@ -201,7 +200,7 @@ func (n *loopbackNode) Symlink(ctx context.Context, target, name string, out *fu
 		return nil, fuse.ToStatus(err)
 	}
 	node := n.rootNode.newLoopbackNode()
-	ch := n.inode().NewInode(node, st.Mode, idFromStat(&st))
+	ch := n.inode().NewInode(node, uint32(st.Mode), idFromStat(&st))
 
 	out.Attr.FromStat(&st)
 	return ch, fuse.OK
@@ -221,7 +220,7 @@ func (n *loopbackNode) Link(ctx context.Context, target Operations, name string,
 		return nil, fuse.ToStatus(err)
 	}
 	node := n.rootNode.newLoopbackNode()
-	ch := n.inode().NewInode(node, st.Mode, idFromStat(&st))
+	ch := n.inode().NewInode(node, uint32(st.Mode), idFromStat(&st))
 
 	out.Attr.FromStat(&st)
 	return ch, fuse.OK
@@ -266,39 +265,7 @@ func (n *loopbackNode) OpenDir(ctx context.Context) fuse.Status {
 }
 
 func (n *loopbackNode) ReadDir(ctx context.Context) (DirStream, fuse.Status) {
-	// XXX should implement streaming read to make sure the API works.
-	f, err := os.Open(n.path())
-	if err != nil {
-		return nil, fuse.ToStatus(err)
-	}
-	defer f.Close()
-
-	var entries []fuse.DirEntry
-	for {
-		want := 100
-		infos, err := f.Readdir(want)
-		for _, info := range infos {
-			s := fuse.ToStatT(info)
-			if s == nil {
-				continue
-			}
-
-			entries = append(entries, fuse.DirEntry{
-				Name: info.Name(),
-				Mode: uint32(s.Mode),
-				Ino:  s.Ino,
-			})
-		}
-		if len(infos) < want || err == io.EOF {
-			break
-		}
-
-		if err != nil {
-			return nil, fuse.ToStatus(err)
-		}
-	}
-
-	return &DirArray{entries}, fuse.OK
+	return NewLoopbackDirStream(n.path())
 }
 
 func (n *loopbackNode) fGetAttr(ctx context.Context, out *fuse.AttrOut) (fuse.Status, bool) {