Reorganization

* update README

* Split off zipfs into zipfs/ directory

* Remove marginally useful stackfs example

README

 
 GO-FUSE: native bindings for the FUSE kernel module.
 
-GETTING STARTED
+HIGHLIGHTS
+
+* High speed: within a factor 2 of C/C++ based filesystems on
+filesystem benchmarks, using the gc compiler.  For many real world
+applications, the difference will be negligible.
+
+* Supports in-process mounting of different PathFileSystems onto each
+other.
+
+* Includes two fleshed out examples, zipfs and unionfs.
+
+
+EXAMPLES
 
 * examplelib/zipfs.go contains a small and simple read-only filesystem
   for zip files. The corresponding command is in example/zipfs/ . For
@@ -12,6 +24,9 @@ GETTING STARTED
     ls /tmp/mountpoint
     fusermount -u /tmp/mountpoint
 
+* examplelib/multizipfs.go shows how to use in-process mounts to
+  combine multiple Go-FUSE filesystems into a larger filesystem.
+    
 * fuse/loopback.go supports all the implemented functionality.  A
   binary to run is in example/loopback/ . For example
 
@@ -20,7 +35,21 @@ GETTING STARTED
     ls /tmp/mountpoint
     fusermount -u /tmp/mountpoint
 
+* unionfs/unionfs.go: implements a union mount using 1 R/W branch, and
+  multiple R/O branches.
 
+    mkdir -p  /tmp/mountpoint /tmp/writable
+    example/unionfs/unionfs /tmp/mountpoint /tmp/writable /usr &
+    ls /tmp/mountpoint
+    ls -l /tmp/mountpoint/bin/vi
+    rm /tmp/mountpoint/bin/vi
+    ls -l /tmp/mountpoint/bin/vi
+    cat /tmp/writable/*DELETION*/* 
+
+* union/autounionfs.go: creates UnionFs mounts automatically based on
+  existence of READONLY symlinks.
+
+    
 Tested on:
 
 - x86 32bits (Fedora 14).
@@ -28,14 +57,6 @@ Tested on:
 
 
 
-BENCHMARKS
-
-In benchmarks, Go-fuse's loopback system is less than 2 times slower
-than equivalent C++ based FUSE filesystems.  In practical applications,
-the the file system client processing may mask some of these
-performance gaps.
-
-
 CREDITS
 
 * Inspired by Taru Karttunen's package, https://bitbucket.org/taruti/go-extra.

all.bash

 #!/bin/sh
 set -eux
 
-for d in fuse examplelib example/loopback example/zipfs \
-    example/bulkstat example/multizip
+
+for d in fuse zipfs unionfs example/loopback example/zipfs \
+    example/bulkstat example/multizip example/unionfs \
+    example/autounionfs ; \
 do
   gomake -C $d "$@"
 done
 
-for d in fuse examplelib
+for d in fuse zipfs unionfs
 do
   (cd $d && gotest )
 done

example/autounionfs/Makefile

+# Use "gomake install" to build and install this package.
+include $(GOROOT)/src/Make.inc
+
+TARG=autounionfs
+GOFILES=main.go
+DEPS=../../fuse ../../unionfs
+
+include $(GOROOT)/src/Make.cmd
+

example/autounionfs/main.go

+package main
+
+import (
+	"flag"
+	"fmt"
+	"github.com/hanwen/go-fuse/fuse"
+	"github.com/hanwen/go-fuse/unionfs"
+	"os"
+)
+
+func main() {
+	debug := flag.Bool("debug", false, "debug on")
+	threaded := flag.Bool("threaded", true, "debug on")
+	delcache_ttl := flag.Float64("deletion_cache_ttl", 5.0, "Deletion cache TTL in seconds.")
+	branchcache_ttl := flag.Float64("branchcache_ttl", 5.0, "Branch cache TTL in seconds.")
+	deldirname := flag.String(
+		"deletion_dirname", "GOUNIONFS_DELETIONS", "Directory name to use for deletions.")
+	flag.Parse()
+
+	if len(flag.Args()) < 2 {
+		fmt.Println("Usage:\n  main MOUNTPOINT BASEDIR")
+		os.Exit(2)
+	}
+	mountpoint := flag.Arg(0)
+
+	ufsOptions := unionfs.UnionFsOptions{
+		DeletionCacheTTLSecs: *delcache_ttl,
+		BranchCacheTTLSecs:   *branchcache_ttl,
+		DeletionDirName:      *deldirname,
+	}
+	options := unionfs.AutoUnionFsOptions{
+		UnionFsOptions: ufsOptions,
+	}
+
+	gofs := unionfs.NewAutoUnionFs(flag.Arg(1), options)
+	conn := fuse.NewPathFileSystemConnector(gofs)
+	mountState := fuse.NewMountState(conn)
+	mountState.Debug = *debug
+	fmt.Printf("Mounting...\n")
+	err := mountState.Mount(mountpoint)
+	if err != nil {
+		fmt.Printf("MountFuse fail: %v\n", err)
+		os.Exit(1)
+	}
+	fmt.Printf("Mounted!\n")
+	mountState.Loop(*threaded)
+}

example/multizip/Makefile

@@ -3,7 +3,7 @@ include $(GOROOT)/src/Make.inc
 
 TARG=multizip
 GOFILES=multizip.go
-DEPS=../../fuse ../../examplelib
+DEPS=../../fuse ../../zipfs
 
 include $(GOROOT)/src/Make.cmd
 

example/multizip/multizip.go

@@ -2,7 +2,7 @@ package main
 
 import (
 	"github.com/hanwen/go-fuse/fuse"
-	"github.com/hanwen/go-fuse/examplelib"
+	zipfs "github.com/hanwen/go-fuse/zipfs"
 	"fmt"
 	"flag"
 	"log"
@@ -20,7 +20,7 @@ func main() {
 		os.Exit(2)
 	}
 
-	fs := examplelib.NewMultiZipFs()
+	fs := zipfs.NewMultiZipFs()
 	state := fuse.NewMountState(fs.Connector)
 
 	mountPoint := flag.Arg(0)

example/zipfs/Makefile

@@ -2,8 +2,9 @@
 include $(GOROOT)/src/Make.inc
 
 TARG=zipfs
-GOFILES=zipfs.go
-DEPS=../../fuse ../../examplelib
+GOFILES=main.go
+
+DEPS=../../fuse ../../zipfs
 
 include $(GOROOT)/src/Make.cmd
 

example/zipfs/zipfs.go → example/zipfs/main.go

@@ -2,7 +2,7 @@ package main
 
 import (
 	"github.com/hanwen/go-fuse/fuse"
-	"github.com/hanwen/go-fuse/examplelib"
+	zipfs "github.com/hanwen/go-fuse/zipfs"
 	"fmt"
 	"flag"
 	"log"
@@ -21,7 +21,7 @@ func main() {
 		os.Exit(2)
 	}
 
-	fs := examplelib.NewZipArchiveFileSystem(flag.Arg(1))
+	fs := zipfs.NewZipArchiveFileSystem(flag.Arg(1))
 	conn := fuse.NewPathFileSystemConnector(fs)
 	state := fuse.NewMountState(conn)
 

examplelib/stackfs_test.go

-package examplelib
-
-import (
-	"github.com/hanwen/go-fuse/fuse"
-	"fmt"
-	"log"
-	"os"
-	"path/filepath"
-	"strings"
-	"testing"
-)
-
-var _ = strings.Join
-var _ = log.Println
-
-////////////////
-
-// Create and mount filesystem.
-const magicMode uint32 = 0753
-
-type stackFsTestCase struct {
-	origDir1 string
-	origDir2 string
-	mountDir string
-	testDir  string
-	tester   *testing.T
-
-	fs    *SubmountFileSystem
-	state *fuse.MountState
-}
-
-func (me *stackFsTestCase) Setup(t *testing.T) {
-	me.tester = t
-
-	me.testDir = fuse.MakeTempDir()
-	me.origDir1 = filepath.Join(me.testDir, "orig1")
-	me.origDir2 = filepath.Join(me.testDir, "orig2")
-	me.mountDir = filepath.Join(me.testDir, "mount")
-
-	os.Mkdir(me.origDir1, 0700)
-	os.Mkdir(me.origDir2, 0700)
-	os.Mkdir(me.mountDir, 0700)
-
-	fs1 := fuse.NewPathFileSystemConnector(fuse.NewLoopbackFileSystem(me.origDir1))
-	fs2 := fuse.NewPathFileSystemConnector(fuse.NewLoopbackFileSystem(me.origDir2))
-
-	me.fs = NewSubmountFileSystem()
-
-	attr := fuse.Attr{
-		Mode: uint32(magicMode),
-	}
-
-	me.fs.AddFileSystem("sub1", fs1, attr)
-	me.fs.AddFileSystem("sub2", fs2, attr)
-
-	me.state = fuse.NewMountState(me.fs)
-	me.state.Mount(me.mountDir)
-
-	me.state.Debug = true
-
-	fmt.Println("tempdir: ", me.testDir)
-
-	// Unthreaded, but in background.
-	go me.state.Loop(false)
-}
-
-// Unmount and del.
-func (me *stackFsTestCase) Cleanup() {
-	fmt.Println("Unmounting.")
-	err := me.state.Unmount()
-	CheckSuccess(err)
-	os.RemoveAll(me.testDir)
-}
-
-////////////////
-
-func (me *stackFsTestCase) testReaddir() {
-	fmt.Println("testReaddir... ")
-	dir, err := os.Open(me.mountDir)
-	CheckSuccess(err)
-	infos, err := dir.Readdir(10)
-	CheckSuccess(err)
-
-	wanted := map[string]bool{
-		"sub1": true,
-		"sub2": true,
-	}
-	if len(wanted) != len(infos) {
-		me.tester.Errorf("Length mismatch %v", infos)
-	} else {
-		for _, v := range infos {
-			_, ok := wanted[v.Name]
-			if !ok {
-				me.tester.Errorf("Unexpected name %v", v.Name)
-			}
-
-			if v.Mode&0777 != magicMode {
-				me.tester.Errorf("Unexpected mode %o, %v", v.Mode, v)
-			}
-		}
-	}
-
-	dir.Close()
-}
-
-
-func (me *stackFsTestCase) testSubFs() {
-	fmt.Println("testSubFs... ")
-	for i := 1; i <= 2; i++ {
-		// orig := filepath.Join(me.testDir, fmt.Sprintf("orig%d", i))
-		mount := filepath.Join(me.mountDir, fmt.Sprintf("sub%d", i))
-
-		name := "testFile"
-
-		mountFile := filepath.Join(mount, name)
-
-		f, err := os.OpenFile(mountFile, os.O_WRONLY, 0)
-		if err == nil {
-			me.tester.Errorf("Expected error for open write %v", name)
-			continue
-		}
-		content1 := "booh!"
-		f, err = os.Create(mountFile)
-		CheckSuccess(err)
-
-		f.Write([]byte(content1))
-		f.Close()
-
-		err = os.Chmod(mountFile, magicMode)
-		CheckSuccess(err)
-
-		fi, err := os.Lstat(mountFile)
-		CheckSuccess(err)
-		if fi.Mode&0777 != magicMode {
-			me.tester.Errorf("Mode %o", fi.Mode)
-		}
-
-		g, err := os.Open(mountFile)
-		CheckSuccess(err)
-
-		buf := make([]byte, 1024)
-		n, err := g.Read(buf)
-		CheckSuccess(err)
-		if string(buf[:n]) != content1 {
-			me.tester.Errorf("content %v", buf[:n])
-		}
-		g.Close()
-	}
-}
-
-func (me *stackFsTestCase) testAddRemove() {
-	me.tester.Log("testAddRemove")
-	attr := fuse.Attr{
-		Mode: 0755,
-	}
-
-	conn := fuse.NewPathFileSystemConnector(fuse.NewLoopbackFileSystem(me.origDir1))
-	ok := me.fs.AddFileSystem("sub1", conn, attr)
-	if ok {
-		me.tester.Errorf("AddFileSystem should fail")
-		return
-	}
-	ok = me.fs.AddFileSystem("third", conn, attr)
-	if !ok {
-		me.tester.Errorf("AddFileSystem fail")
-	}
-	conn.Init(new(fuse.InHeader), new(fuse.InitIn))
-
-	fi, err := os.Lstat(filepath.Join(me.mountDir, "third"))
-	CheckSuccess(err)
-
-	if !fi.IsDirectory() {
-		me.tester.Errorf("not a directory %v", fi)
-	}
-
-	fs := me.fs.RemoveFileSystem("third")
-	if fs == nil {
-		me.tester.Errorf("remove fail")
-	}
-	dir, err := os.Open(me.mountDir)
-	CheckSuccess(err)
-	infos, err := dir.Readdir(10)
-	CheckSuccess(err)
-	if len(infos) != 2 {
-		me.tester.Errorf("lstat expect 2 infos %v", infos)
-	}
-	dir.Close()
-
-	_, err = os.Open(filepath.Join(me.mountDir, "third"))
-	if err == nil {
-		me.tester.Errorf("expect enoent %v", err)
-	}
-}
-
-func TestStackFS(t *testing.T) {
-	ts := new(stackFsTestCase)
-	ts.Setup(t)
-
-	ts.testReaddir()
-	ts.testSubFs()
-	ts.testAddRemove()
-
-	ts.Cleanup()
-}

fuse/Makefile

@@ -2,7 +2,6 @@
 include $(GOROOT)/src/Make.inc
 
 TARG=github.com/hanwen/go-fuse/fuse
-#TARG=fuse
 
 GOFILES=misc.go\
 	fuse.go\

unionfs/autounion.go

@@ -60,7 +60,7 @@ func (me *AutoUnionFs) addFs(roots []string) {
 	var gofs *UnionFs
 	if me.knownFilesystems[name] == nil {
 		log.Println("Adding UnionFs for roots", roots)
-		gofs = NewUnionfs(roots, me.options.UnionFsOptions)
+		gofs = NewUnionFs(roots, me.options.UnionFsOptions)
 		me.knownFilesystems[name] = gofs
 	}
 	me.lock.Unlock()

unionfs/unionfs.go

@@ -78,7 +78,7 @@ type UnionFsOptions struct {
 	DeletionDirName      string
 }
 
-func NewUnionfs(roots []string, options UnionFsOptions) *UnionFs {
+func NewUnionFs(roots []string, options UnionFsOptions) *UnionFs {
 	g := new(UnionFs)
 
 	g.options = &options

unionfs/unionfs_test.go

@@ -38,7 +38,7 @@ func setup(t *testing.T) (workdir string, state *fuse.MountState) {
 	var roots []string
 	roots = append(roots, wd+"/rw")
 	roots = append(roots, wd+"/ro")
-	ufs := NewUnionfs(roots, testOpts)
+	ufs := NewUnionFs(roots, testOpts)
 
 	connector := fuse.NewPathFileSystemConnector(ufs)
 	state = fuse.NewMountState(connector)

zipfs/Makefile

+# Use "gomake install" to build and install this package.
+include $(GOROOT)/src/Make.inc
+
+TARG=github.com/hanwen/go-fuse/zipfs
+DEPS=../fuse
+
+GOFILES=zipfs.go \
+	multizip.go \
+
+include $(GOROOT)/src/Make.pkg
+

examplelib/multizip_test.go → zipfs/multizip_test.go

@@ -2,11 +2,19 @@ package examplelib
 
 import (
 	"github.com/hanwen/go-fuse/fuse"
+	"log"
 	"os"
 	"testing"
 	"time"
 )
 
+func CheckSuccess(err os.Error) {
+	if err != nil {
+		log.Println(err)
+		panic("error")
+	}
+}
+
 func TestMultiZipFs(t *testing.T) {
 	var err os.Error
 
@@ -48,7 +56,9 @@ func TestMultiZipFs(t *testing.T) {
 	CheckSuccess(err)
 
 	// Directory exists, but is empty.
-	if !IsDir(mountPoint + "/zipmount") {
+	fi, err := os.Lstat(mountPoint + "/zipmount")
+	CheckSuccess(err)
+	if !fi.IsDirectory() {
 		t.Errorf("Expect directory at /zipmount")
 	}
 
@@ -63,13 +73,13 @@ func TestMultiZipFs(t *testing.T) {
 
 	err = f.Close()
 	CheckSuccess(err)
-
-	if !IsDir(mountPoint + "/zipmount") {
+	fi, err = os.Lstat(mountPoint + "/zipmount") 
+	if !fi.IsDirectory() {
 		t.Errorf("Expect directory at /zipmount")
 	}
 
 	// Check that zipfs itself works.
-	fi, err := os.Stat(mountPoint + "/zipmount/subdir")
+	fi, err = os.Stat(mountPoint + "/zipmount/subdir")
 	CheckSuccess(err)
 	if !fi.IsDirectory() {
 		t.Error("directory type", fi)