fusego/samples/mount_sample/mount.go

154 lines
3.8 KiB
Go

// Copyright 2015 Google Inc. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// A simple tool for mounting sample file systems, used by the tests in
// samples/.
package main
import (
"context"
"errors"
"flag"
"fmt"
"log"
"os"
"runtime"
"syscall"
"github.com/jacobsa/fuse"
"github.com/jacobsa/fuse/samples/flushfs"
)
var fType = flag.String("type", "", "The name of the samples/ sub-dir.")
var fMountPoint = flag.String("mount_point", "", "Path to mount point.")
var fReadyFile = flag.Uint64("ready_file", 0, "FD to signal when ready.")
var fFlushesFile = flag.Uint64("flushfs.flushes_file", 0, "")
var fFsyncsFile = flag.Uint64("flushfs.fsyncs_file", 0, "")
var fFlushError = flag.Int("flushfs.flush_error", 0, "")
var fFsyncError = flag.Int("flushfs.fsync_error", 0, "")
var fReadOnly = flag.Bool("read_only", false, "Mount in read-only mode.")
var fDebug = flag.Bool("debug", false, "Enable debug logging.")
func makeFlushFS() (fuse.Server, error) {
// Check the flags.
if *fFlushesFile == 0 || *fFsyncsFile == 0 {
return nil, fmt.Errorf("You must set the flushfs flags.")
}
// Set up the files.
flushes := os.NewFile(uintptr(*fFlushesFile), "(flushes file)")
fsyncs := os.NewFile(uintptr(*fFsyncsFile), "(fsyncs file)")
// Set up errors.
var flushErr error
var fsyncErr error
if *fFlushError != 0 {
flushErr = syscall.Errno(*fFlushError)
}
if *fFsyncError != 0 {
fsyncErr = syscall.Errno(*fFsyncError)
}
// Report flushes and fsyncs by writing the contents followed by a newline.
report := func(f *os.File, outErr error) func(string) error {
return func(s string) error {
buf := []byte(s)
buf = append(buf, '\n')
if _, err := f.Write(buf); err != nil {
return fmt.Errorf("Write: %v", err)
}
return outErr
}
}
reportFlush := report(flushes, flushErr)
reportFsync := report(fsyncs, fsyncErr)
// Create the file system.
return flushfs.NewFileSystem(reportFlush, reportFsync)
}
func makeFS() (fuse.Server, error) {
switch *fType {
default:
return nil, fmt.Errorf("Unknown FS type: %v", *fType)
case "flushfs":
return makeFlushFS()
}
}
func getReadyFile() (*os.File, error) {
if *fReadyFile == 0 {
return nil, errors.New("You must set --ready_file.")
}
return os.NewFile(uintptr(*fReadyFile), "(ready file)"), nil
}
func main() {
flag.Parse()
// Allow parallelism in the file system implementation, to help flush out
// bugs like https://github.com/jacobsa/fuse/issues/4.
runtime.GOMAXPROCS(2)
// Grab the file to signal when ready.
readyFile, err := getReadyFile()
if err != nil {
log.Fatalf("getReadyFile: %v", err)
}
// Create an appropriate file system.
server, err := makeFS()
if err != nil {
log.Fatalf("makeFS: %v", err)
}
// Mount the file system.
if *fMountPoint == "" {
log.Fatalf("You must set --mount_point.")
}
cfg := &fuse.MountConfig{
ReadOnly: *fReadOnly,
}
if *fDebug {
cfg.DebugLogger = log.New(os.Stderr, "fuse: ", 0)
}
mfs, err := fuse.Mount(*fMountPoint, server, cfg)
if err != nil {
log.Fatalf("Mount: %v", err)
}
// Signal that it is ready.
_, err = readyFile.Write([]byte("x"))
if err != nil {
log.Fatalf("readyFile.Write: %v", err)
}
// Wait for it to be unmounted.
if err = mfs.Join(context.Background()); err != nil {
log.Fatalf("Join: %v", err)
}
}