.

wcfs/wcfs.go

@@ -495,10 +495,12 @@ type BigFile struct {
 	head	*Head
 
 	// ZBigFile top-level object. Kept activated during lifetime of current transaction.
+	// XXX kill "Kept activated ..."
 	zbf	*ZBigFile
 
 	// zbf.Size(). It is constant during lifetime of current transaction.
-	zbfSize int64
+	blksize int64 // zbf.blksize
+	zbfSize int64 // zbf.Size()	XXX -> .size
 
 	// tail change history of this file.
 	δFtail *ΔTailI64 // [](rev↑, []#blk)
@@ -1215,7 +1217,7 @@ func (f *BigFile) getattr(out *fuse.Attr) {
 	// .Blksize
 
 	// FIXME lastChange should cover all bigfile data, not only ZBigFile itself
-	//mtime := f.δFtail[-1] || zbf.PSerial?
+	// XXX -> f.lastRev	(initially serial, later ~  f.δFtail[-1])
 	lastChange := f.zbf.PSerial()	// XXX activate (if zbf becomes not activated during txn)
 
 	mtime := lastChange.Time().Time
@@ -1228,8 +1230,6 @@ func (f *BigFile) Read(_ nodefs.File, dest []byte, off int64, fctx *fuse.Context
 	f.head.zconnMu.RLock()
 	defer f.head.zconnMu.RUnlock()
 
-	zbf := f.zbf
-
 	// cap read request to file size
 	end := off + int64(len(dest))		// XXX overflow?
 	if end > f.zbfSize {
@@ -1240,6 +1240,8 @@ func (f *BigFile) Read(_ nodefs.File, dest []byte, off int64, fctx *fuse.Context
 		return fuse.ReadResultData(nil), fuse.OK
 	}
 
+	zbf := f.zbf
+
 	// widen read request to be aligned with blksize granularity
 	// (we can load only whole ZBlk* blocks)
 	aoff := off - (off % zbf.blksize)
@@ -1267,6 +1269,7 @@ func (f *BigFile) Read(_ nodefs.File, dest []byte, off int64, fctx *fuse.Context
 
 	err := wg.Wait()
 	if err != nil {
+		// XXX -> err2LogStatus
 		log.Errorf("%s", err)	// XXX + /bigfile/XXX: read [a,b): -> ...
 		return nil, fuse.EIO
 	}