.

wcfs/misc.go

@@ -235,6 +235,7 @@ func (sk *FileSock) File() nodefs.File {
 // The data will be read by client reading from filesock's file.
 // Write semantic is that of io.Writer.
 func (sk *FileSock) Write(data []byte) (n int, err error) {
+	// XXX err ctx?
 	return sk.tx.Write(data)
 }
 
@@ -259,6 +260,7 @@ func (f *skFile) Read(dest []byte, /*ignored*/off int64) (fuse.ReadResult, fuse.
 // The data read will be that the client writes into filesock's file.
 // Read semantic is that of io.Reader.
 func (sk *FileSock) Read(dest []byte) (n int, err error) {
+	// XXX err ctx?
 	return sk.rx.Read(dest)
 }
 
@@ -285,17 +287,17 @@ func (f *skFile) Write(data []byte, /*ignored*/off int64) (uint32, fuse.Status)
 }
 
 
-// CloseRead closes reading side of the socket.
+// CloseRead closes reading side of filesock.
 func (sk *FileSock) CloseRead() error {
 	return sk.rx.Close()
 }
 
-// CloseWrite closes writing side of the socket.
+// CloseWrite closes writing side of filesock.
 func (sk *FileSock) CloseWrite() error {
 	return sk.tx.Close()
 }
 
-// Close closes the socket.
+// Close closes filesock.
 //
 // it is semantically equivalent to CloseRead + CloseWrite.
 func (sk *FileSock) Close() error {

wcfs/wcfs.go

@@ -529,13 +529,13 @@ func (cc *zodbCacheControl) WantEvict(obj zodb.IPersistent) bool {
 
 // zwatcher watches for ZODB changes.
 // see "4) when we receive an invalidation message from ZODB ..."
-func (r *Root) zwatcher(ctx context.Context) (err error) {
+func (root *Root) zwatcher(ctx context.Context) (err error) {
 	defer xerr.Contextf(&err, "zwatch")	// XXX more in context?
 	// XXX unmount on error? -> always EIO?
 
 	zwatchq := make(chan zodb.CommitEvent)
-	r.zstor.AddWatch(zwatchq)
-	defer r.zstor.DelWatch(zwatchq)
+	root.zstor.AddWatch(zwatchq)
+	defer root.zstor.DelWatch(zwatchq)
 
 	var zevent zodb.CommitEvent
 	var ok bool
@@ -551,19 +551,19 @@ func (r *Root) zwatcher(ctx context.Context) (err error) {
 			}
 		}
 
-		r.zhandle1(zevent)
+		root.zhandle1(zevent)
 	}
 }
 
 // zhandle1 handles 1 event from ZODB notification.
-func (r *Root) zhandle1(zevent zodb.CommitEvent) {
+func (root *Root) zhandle1(zevent zodb.CommitEvent) {
 	// while we are invalidating OS cache, make sure that nothing, that
 	// even reads /head/bigfile/*, is running (see 4.6).
-	r.head.zconnMu.Lock()
-	defer r.head.zconnMu.Unlock()
+	root.head.zconnMu.Lock()
+	defer root.head.zconnMu.Unlock()
 
-	zhead := r.head.zconn
-	bfdir := r.head.bfdir
+	zhead := root.head.zconn
+	bfdir := root.head.bfdir
 
 	toinvalidate := map[*BigFile]SetI64{} // {} file -> set(#blk)
 
@@ -626,12 +626,15 @@ func (r *Root) zhandle1(zevent zodb.CommitEvent) {
 
 	// XXX resync .zhead to zevent.tid
 
-/* XXX reenable
 	// notify .wcfs/zhead
-	for fh := range gdebug.zhead.fhTab {
-		fh.Write(fmt.Sprintf("%s\n", zevent.Tid))	// XXX -> fh = filesock
+	for sk := range gdebug.zheadSockTab {
+		_, err := fmt.Fprintf(sk, "%s\n", zevent.Tid)
+		if err != nil {
+			log.Error(err)	// XXX errctx, -> warning?
+			sk.Close()
+			delete(gdebug.zheadSockTab, sk)
+		}
 	}
-*/
 }
 
 // invalidateBlk invalidates 1 file block.	XXX
@@ -1151,6 +1154,30 @@ var gfsconn *nodefs.FileSystemConnector
 // so we still have to reference the root via path.
 var gmntpt string
 
+// debugging
+var gdebug = struct {
+	// .wcfs/zhead opens
+	// protected by groot.head.zconnMu
+	zheadSockTab map[*FileSock]struct{}
+}{}
+
+// _wcfs_Zhead serves .wcfs/zhead opens.
+type _wcfs_Zhead struct {
+	nodefs.Node
+}
+
+func (zh *_wcfs_Zhead) Open(flags uint32, fctx *fuse.Context) (nodefs.File, fuse.Status) {
+	// XXX check flags?
+	sk := NewFileSock()
+	sk.CloseRead()
+
+	groot.head.zconnMu.Lock()
+	defer groot.head.zconnMu.Unlock()
+
+	gdebug.zheadSockTab[sk] = struct{}{}
+	return sk.File(), fuse.OK
+}
+
 func main() {
 	stdlog.SetPrefix("wcfs: ")
 	//log.CopyStandardLogTo("WARNING") // XXX -> "DEBUG" if -d ?
@@ -1242,9 +1269,9 @@ func main() {
 	// XXX ^^^ invalidate cache or direct io
 
 	// for debugging/testing
-	dotwcfs := nodefs.NewDefaultNode()
-	mkdir(root, ".wcfs", dotwcfs)
-	mkfile(dotwcfs, "zurl", NewStaticFile([]byte(zurl)))
+	_wcfs := nodefs.NewDefaultNode()
+	mkdir(root, ".wcfs", _wcfs)
+	mkfile(_wcfs, "zurl", NewStaticFile([]byte(zurl)))
 
 	// .wcfs/zhead - special file channel that sends zhead.at.
 	//
@@ -1252,7 +1279,9 @@ func main() {
 	// zhead.at was, starting from the time when .wcfs/zhead was opened.
 	// There can be multiple openers. Once opened, the file must be read,
 	// as wcfs blocks waiting for data to be read.
-	//mkfile(dotwcfs, "zhead", ...)	XXX reenable
+	mkfile(_wcfs, "zhead", &_wcfs_Zhead{
+		Node: nodefs.NewDefaultNode(),
+	})
 
 	// TODO handle autoexit
 	_ = autoexit