.

wcfs/misc.go

@@ -25,6 +25,7 @@ import (
 	"fmt"
 	"io"
 	"math"
+	"strings"
 	"sync/atomic"
 	"syscall"
 
@@ -601,6 +602,47 @@ func tidmin(a, b zodb.Tid) zodb.Tid {
 	}
 }
 
+// ---- parsing ----
+
+// parseWatch parses watch request wcfs received over /head/watch.
+//
+//	watch <file> (@<at>|-)
+func parseWatch(msg string) (oid zodb.Oid, at zodb.Tid, err error) {
+	defer func() {
+		if err != nil {
+			oid = zodb.InvalidOid
+			at  = zodb.InvalidTid
+			err = fmt.Errorf("bad watch: %s", err)
+		}
+	}()
+
+	msg = strings.TrimSuffix(msg, "\n")
+	if !strings.HasPrefix(msg, "watch ") {
+		return 0, 0, fmt.Errorf("not a watch request")
+	}
+	argv := strings.Split(msg[len("watch "):], " ")
+	if len(argv) != 2 {
+		return 0, 0, fmt.Errorf("expected 2 arguments, got %d", len(argv))
+	}
+	oid, err = zodb.ParseOid(argv[0])
+	if err != nil {
+		return 0, 0, fmt.Errorf("invalid oid")
+	}
+
+	switch {
+	case argv[1] == "-":
+		at = zodb.InvalidTid
+	case strings.HasPrefix(argv[1], "@"):
+		at, err = zodb.ParseTid(argv[1][1:])
+	default:
+		err = fmt.Errorf("x") // XXX just anything
+	}
+	if err != nil {
+		return 0, 0, fmt.Errorf("invalid at")
+	}
+
+	return oid, at, nil
+}
 
 // ---- make df happy (else it complains "function not supported") ----
 

wcfs/wcfs.go

@@ -1250,7 +1250,7 @@ func (watch *Watch) Open(flags uint32, fctx *fuse.Context) (nodefs.File, fuse.St
 	// XXX check flags?
 	w := &Watcher{
 		sk:      NewFileSock(),
-		id:      atomic.AddInt32(&watch.id, +1),
+		id:      atomic.AddInt32(&watch.idNext, +1),
 		fileTab: make(map[*FileWatch]struct{}),
 	}
 
@@ -1267,6 +1267,7 @@ func (watch *Watch) Open(flags uint32, fctx *fuse.Context) (nodefs.File, fuse.St
 func (w *Watcher) serve() {
 	err := w._serve()
 	// XXX log error if !close
+	// XXX close if was not closed?
 	// XXX locking
 	delete(w.head.watchTab, w)
 }
@@ -1316,29 +1317,12 @@ func (w *Watcher) _serve() (err error) {
 		}
 
 		// client-initiated request
-		msg = strings.TrimSuffix(msg, "\n")
-		msgv = strings.Split(msg, " ")
-		if !(len(msgv) == 3 && msgv[0] != "watch") {
-			// XXX write to peer too
-			return fmt.Errorf("rx %d: invalid request", stream)
-		}
-		oid, err := zodb.ParseOid(msgv[1])
+		oid, at, err = parseWatch(msg)
 		if err != nil {
-			return fmt.Errorf("rx %d: bad watch: invalid oid")
+			// XXX write to peer too
+			return fmt.Errorf("rx %d: %s", err)
 		}
 
-		var at zodb.Tid
-		switch {
-		case msgv[2] == "-":
-			at = zodb.InvalidTid
-		case strings.HasPrefix(msgv[2], "@"):
-			at, err = zodb.ParseTid(msgv[2][1:])
-		default:
-			err = fmt.Errorf("x") // XXX just anything
-		}
-		if err != nil {
-			return fmt.Errorf("rx %d: bad watch: invalid at")
-		}
 
 	}
 }