inspectors/fs: implement Fsync

Required by TiKV community: tikv/tikv#846

nmz/inspector/fs/fs.go

@@ -166,3 +166,25 @@ func (this *FilesystemInspector) PostRmdir(realRetCode int32, ctx hookfs.HookCon
 	log.Debugf("PostRmdir %s", ctx)
 	return nil, false
 }
+
+// implements hookfs.HookOnFsync
+func (this *FilesystemInspector) PreFsync(path string, flags uint32) (error, bool, hookfs.HookContext) {
+	ctx := EQFSHookContext{Path: path}
+	log.Debugf("PreFsync %s", ctx)
+	err, hooked := this.commonHook(PreFsync, path, map[string]interface{}{})
+	if hooked {
+		return err, true, ctx
+	} else {
+		if err != nil {
+			log.Error(err)
+		}
+		return nil, false, ctx
+	}
+	// NOTREACHED
+}
+
+// implements hookfs.HookOnFsync
+func (this *FilesystemInspector) PostFsync(realRetCode int32, ctx hookfs.HookContext) (error, bool) {
+	log.Debugf("PostFsync %s", ctx)
+	return nil, false
+}

nmz/inspector/fs/fs_test.go

@@ -54,6 +54,7 @@ func TestFilesystemInspectorInterfaceImpl(t *testing.T) {
 	func(x hookfs.HookOnMkdir) {}(h)
 	func(x hookfs.HookOnRmdir) {}(h)
 	func(x hookfs.HookOnOpenDir) {}(h)
+	func(x hookfs.HookOnFsync) {}(h)
 }
 
 func newFUSEServer(t *testing.T, fs *hookfs.HookFs) *fuse.Server {

nmz/signal/event_filesystem.go

@@ -32,6 +32,7 @@ const (
 	PreWrite = "pre-write"
 	PreMkdir = "pre-mkdir"
 	PreRmdir = "pre-rmdir"
+	PreFsync = "pre-fsync"
 )
 
 func NewFilesystemEvent(entityID string, op FilesystemOp, path string, m map[string]interface{}) (Event, error) {