From 2a4f274fbc754487223614361a195c26009d877d Mon Sep 17 00:00:00 2001
From: Alex Yatskov <alex@foosoft.net>
Date: Tue, 23 Jun 2015 17:43:22 +0900
Subject: [PATCH] Improving command line support

---
 database.go | 29 ++++++++++++++++++++--------
 vfs.go      | 54 ++++++++++++++++++++++++++++++++---------------------
 2 files changed, 54 insertions(+), 29 deletions(-)

diff --git a/database.go b/database.go
index 18b3f49..9561084 100644
--- a/database.go
+++ b/database.go
@@ -23,6 +23,7 @@
 package main
 
 import (
+	"fmt"
 	"io/ioutil"
 	"path"
 	"path/filepath"
@@ -40,16 +41,16 @@ type database struct {
 	vers verList
 }
 
-func newDatabase(dir string) (*database, error) {
+func newDatabase(dir string, index int, writable bool) (*database, error) {
 	db := &database{base: dir}
-	if err := db.load(dir); err != nil {
+	if err := db.load(dir, index, writable); err != nil {
 		return nil, err
 	}
 
 	return db, nil
 }
 
-func (db *database) load(dir string) error {
+func (db *database) load(dir string, index int, writable bool) error {
 	var err error
 
 	db.base, err = filepath.Abs(dir)
@@ -57,8 +58,10 @@ func (db *database) load(dir string) error {
 		return err
 	}
 
-	if err := buildNewVersion(db.base); err != nil {
-		return err
+	if writable {
+		if err := buildNewVersion(db.base); err != nil {
+			return err
+		}
 	}
 
 	db.vers, err = db.buildVersions(db.base)
@@ -66,6 +69,10 @@ func (db *database) load(dir string) error {
 		return err
 	}
 
+	if index >= 0 {
+		db.vers = db.vers[index:]
+	}
+
 	if lastVer := db.lastVersion(); lastVer != nil {
 		return lastVer.resolve()
 	}
@@ -112,10 +119,10 @@ func (db *database) buildVersions(base string) (verList, error) {
 
 	sort.Sort(vers)
 
-	var parVer *version
+	var pv *version
 	for _, ver := range vers {
-		ver.parent = parVer
-		parVer = ver
+		ver.parent = pv
+		pv = ver
 	}
 
 	return vers, nil
@@ -130,6 +137,12 @@ func (db *database) lastVersion() *version {
 	return db.vers[count-1]
 }
 
+func (db *database) dump() {
+	for index, ver := range db.vers {
+		fmt.Printf("version: %d\ttime: %s\n", index, ver.timestamp.String())
+	}
+}
+
 // FS
 func (db *database) Root() (fs.Node, error) {
 	return db.lastVersion().root, nil
diff --git a/vfs.go b/vfs.go
index 8ff5905..2870606 100644
--- a/vfs.go
+++ b/vfs.go
@@ -30,49 +30,61 @@ import (
 
 	"bazil.org/fuse"
 	"bazil.org/fuse/fs"
-	_ "bazil.org/fuse/fs/fstestutil"
+	// _ "bazil.org/fuse/fs/fstestutil"
 )
 
 func usage() {
-	fmt.Fprintf(os.Stderr, "Usage: %s [options] database mountpoint\n\n", os.Args[0])
+	fmt.Fprintf(os.Stderr, "Usage: %s [options] database [mountpoint]\n\n", os.Args[0])
 	fmt.Fprintf(os.Stderr, "Parameters:\n")
 	flag.PrintDefaults()
 }
 
 func main() {
+	version := flag.Int("version", -1, "version index (specify -1 for latest)")
 	flag.Usage = usage
 	flag.Parse()
 
-	if flag.NArg() != 2 {
+	if flag.NArg() < 1 {
 		usage()
 		os.Exit(2)
 	}
 
-	database := flag.Arg(0)
-	mountpoint := flag.Arg(1)
+	mount := flag.NArg() > 1
+	writable := mount && *version < 0
 
-	db, err := newDatabase(database)
+	db, err := newDatabase(flag.Arg(0), *version, writable)
 	if err != nil {
 		log.Fatal(err)
 	}
 
-	conn, err := fuse.Mount(mountpoint)
-	if err != nil {
-		log.Fatal(err)
-	}
-	defer conn.Close()
+	if mount {
+		var options []fuse.MountOption
+		if !writable {
+			options = append(options, fuse.ReadOnly())
+		}
 
-	err = fs.Serve(conn, db)
-	if err != nil {
-		log.Fatal(err)
-	}
+		conn, err := fuse.Mount(flag.Arg(1), options...)
+		if err != nil {
+			log.Fatal(err)
+		}
+		defer conn.Close()
 
-	<-conn.Ready
-	if err := conn.MountError; err != nil {
-		log.Fatal(err)
-	}
+		err = fs.Serve(conn, db)
+		if err != nil {
+			log.Fatal(err)
+		}
 
-	if err := db.save(); err != nil {
-		log.Fatal(err)
+		<-conn.Ready
+		if err := conn.MountError; err != nil {
+			log.Fatal(err)
+		}
+
+		if writable {
+			if err := db.save(); err != nil {
+				log.Fatal(err)
+			}
+		}
+	} else {
+		db.dump()
 	}
 }