various: create debug package

Add debug.Server which wraps a NineServer and logs before and after
calling functions for the underlying server. Add Trace option to
protocol.Server.

Makes Harvey-OS#34 obsolete

cmd/ufs/ufs.go

@@ -9,6 +9,7 @@ import (
 	"log"
 	"net"
 
+	"github.com/Harvey-OS/ninep/debug"
 	"github.com/Harvey-OS/ninep/filesystem"
 	"github.com/Harvey-OS/ninep/protocol"
 )
@@ -17,39 +18,37 @@ var (
 	ntype = flag.String("ntype", "tcp4", "Default network type")
 	naddr = flag.String("addr", ":5640", "Network address")
 	root  = flag.String("root", "/", "filesystem root")
-	debug = flag.Bool("debug", false, "enable debug messages")
+	trace = flag.Bool("trace", false, "enable debug messages")
 )
 
+func checkErr(format string, err error) {
+	if err != nil {
+		log.Fatalf(format, err)
+	}
+}
+
 func main() {
 	flag.Parse()
 
-	ln, err := net.Listen(*ntype, *naddr)
-	if err != nil {
-		log.Fatalf("Listen failed: %v", err)
+	var tracer protocol.Tracer
+	if *trace {
+		tracer = log.Printf
 	}
 
-	fs, err := ufs.NewServer(ufs.Root(*root), func(fs *ufs.FileServer) error {
-		if *debug {
-			return ufs.Trace(log.Printf)(fs)
-		}
+	ln, err := net.Listen(*ntype, *naddr)
+	checkErr("Listen failed: %v", err)
 
-		return nil
-	})
+	fs, err := ufs.NewServer(ufs.Root(*root), ufs.Trace(tracer))
+	checkErr("ufs.NewServer failed: %v", err)
 
 	var ninefs protocol.NineServer = fs
-	if *debug {
-		ninefs = fs.Debug()
+	if *trace {
+		ninefs, err = debug.NewServer(ninefs, debug.Trace(tracer))
+		checkErr("debug.NewServer failed: %v", err)
 	}
 
-	s, err := protocol.NewServer(ninefs, func(s *protocol.Server) error {
-		if *debug {
-			s.Trace = log.Printf
-		}
+	s, err := protocol.NewServer(ninefs, protocol.Trace(tracer))
+	checkErr("protocol.NewServer failed: %v", err)
 
-		return nil
-	})
-
-	if err := s.Serve(ln); err != nil {
-		log.Fatal(err)
-	}
+	checkErr("Serve failed: %v", s.Serve(ln))
 }

debug/debug.go

@@ -0,0 +1,180 @@
+// Copyright 2009 The Ninep 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 debug
+
+import (
+	"bytes"
+
+	"github.com/Harvey-OS/ninep/protocol"
+)
+
+type Server struct {
+	protocol.NineServer
+
+	trace protocol.Tracer
+}
+
+type ServerOpt func(*Server) error
+
+func NewServer(s protocol.NineServer, opts ...ServerOpt) (*Server, error) {
+	s2 := &Server{NineServer: s}
+
+	for _, opt := range opts {
+		if err := opt(s2); err != nil {
+			return nil, err
+		}
+	}
+
+	return s2, nil
+}
+
+func Trace(tracer protocol.Tracer) ServerOpt {
+	return func(s *Server) error {
+		s.trace = tracer
+		return nil
+	}
+}
+
+func (s *Server) logf(format string, args ...interface{}) {
+	if s.trace != nil {
+		s.trace(format, args...)
+	}
+}
+
+func (s *Server) Rversion(msize protocol.MaxSize, version string) (protocol.MaxSize, string, error) {
+	s.logf(">>> Tversion %v %v\n", msize, version)
+	msize, version, err := s.NineServer.Rversion(msize, version)
+	if err == nil {
+		s.logf("<<< Rversion %v %v\n", msize, version)
+	} else {
+		s.logf("<<< Error %v\n", err)
+	}
+	return msize, version, err
+}
+
+func (s *Server) Rattach(fid protocol.FID, afid protocol.FID, uname string, aname string) (protocol.QID, error) {
+	s.logf(">>> Tattach fid %v,  afid %v, uname %v, aname %v\n", fid, afid,
+		uname, aname)
+	qid, err := s.NineServer.Rattach(fid, afid, uname, aname)
+	if err == nil {
+		s.logf("<<< Rattach %v\n", qid)
+	} else {
+		s.logf("<<< Error %v\n", err)
+	}
+	return qid, err
+}
+
+func (s *Server) Rflush(o protocol.Tag) error {
+	s.logf(">>> Tflush tag %v\n", o)
+	err := s.NineServer.Rflush(o)
+	if err == nil {
+		s.logf("<<< Rflush\n")
+	} else {
+		s.logf("<<< Error %v\n", err)
+	}
+	return err
+}
+
+func (s *Server) Rwalk(fid protocol.FID, newfid protocol.FID, paths []string) ([]protocol.QID, error) {
+	s.logf(">>> Twalk fid %v, newfid %v, paths %v\n", fid, newfid, paths)
+	qid, err := s.NineServer.Rwalk(fid, newfid, paths)
+	if err == nil {
+		s.logf("<<< Rwalk %v\n", qid)
+	} else {
+		s.logf("<<< Error %v\n", err)
+	}
+	return qid, err
+}
+
+func (s *Server) Ropen(fid protocol.FID, mode protocol.Mode) (protocol.QID, protocol.MaxSize, error) {
+	s.logf(">>> Topen fid %v, mode %v\n", fid, mode)
+	qid, iounit, err := s.NineServer.Ropen(fid, mode)
+	if err == nil {
+		s.logf("<<< Ropen %v %v\n", qid, iounit)
+	} else {
+		s.logf("<<< Error %v\n", err)
+	}
+	return qid, iounit, err
+}
+
+func (s *Server) Rcreate(fid protocol.FID, name string, perm protocol.Perm, mode protocol.Mode) (protocol.QID, protocol.MaxSize, error) {
+	s.logf(">>> Tcreate fid %v, name %v, perm %v, mode %v\n", fid, name,
+		perm, mode)
+	qid, iounit, err := s.NineServer.Rcreate(fid, name, perm, mode)
+	if err == nil {
+		s.logf("<<< Rcreate %v %v\n", qid, iounit)
+	} else {
+		s.logf("<<< Error %v\n", err)
+	}
+	return qid, iounit, err
+}
+
+func (s *Server) Rclunk(fid protocol.FID) error {
+	s.logf(">>> Tclunk fid %v\n", fid)
+	err := s.NineServer.Rclunk(fid)
+	if err == nil {
+		s.logf("<<< Rclunk\n")
+	} else {
+		s.logf("<<< Error %v\n", err)
+	}
+	return err
+}
+
+func (s *Server) Rstat(fid protocol.FID) ([]byte, error) {
+	s.logf(">>> Tstat fid %v\n", fid)
+	b, err := s.NineServer.Rstat(fid)
+	if err == nil {
+		dir, _ := protocol.Unmarshaldir(bytes.NewBuffer(b))
+		s.logf("<<< Rstat %v\n", dir)
+	} else {
+		s.logf("<<< Error %v\n", err)
+	}
+	return b, err
+}
+
+func (s *Server) Rwstat(fid protocol.FID, b []byte) error {
+	dir, _ := protocol.Unmarshaldir(bytes.NewBuffer(b))
+	s.logf(">>> Twstat fid %v, %v\n", fid, dir)
+	err := s.NineServer.Rwstat(fid, b)
+	if err == nil {
+		s.logf("<<< Rwstat\n")
+	} else {
+		s.logf("<<< Error %v\n", err)
+	}
+	return err
+}
+
+func (s *Server) Rremove(fid protocol.FID) error {
+	s.logf(">>> Tremove fid %v\n", fid)
+	err := s.NineServer.Rremove(fid)
+	if err == nil {
+		s.logf("<<< Rremove\n")
+	} else {
+		s.logf("<<< Error %v\n", err)
+	}
+	return err
+}
+
+func (s *Server) Rread(fid protocol.FID, o protocol.Offset, c protocol.Count) ([]byte, error) {
+	s.logf(">>> Tread fid %v, off %v, count %v\n", fid, o, c)
+	b, err := s.NineServer.Rread(fid, o, c)
+	if err == nil {
+		s.logf("<<< Rread %v\n", len(b))
+	} else {
+		s.logf("<<< Error %v\n", err)
+	}
+	return b, err
+}
+
+func (s *Server) Rwrite(fid protocol.FID, o protocol.Offset, b []byte) (protocol.Count, error) {
+	s.logf(">>> Twrite fid %v, off %v, count %v\n", fid, o, len(b))
+	c, err := s.NineServer.Rwrite(fid, o, b)
+	if err == nil {
+		s.logf("<<< Rwrite %v\n", c)
+	} else {
+		s.logf("<<< Error %v\n", err)
+	}
+	return c, err
+}