Commit 11e7a712 authored by Zahoor Mohamed's avatar Zahoor Mohamed Committed by Felix Lange

swarm/api: support mounting manifests via FUSE (#3690)

parent 61d2150a
......@@ -5,19 +5,34 @@ matrix:
include:
- os: linux
dist: trusty
sudo: required
go: 1.7.5
script:
- sudo -E apt-get -yq --no-install-suggests --no-install-recommends --force-yes install fuse
- sudo modprobe fuse
- sudo chmod 666 /dev/fuse
- sudo chown root:$USER /etc/fuse.conf
# These are the latest Go versions, only run go vet and misspell on these
- os: linux
dist: trusty
sudo: required
go: 1.8
script:
- sudo -E apt-get -yq --no-install-suggests --no-install-recommends --force-yes install fuse
- sudo modprobe fuse
- sudo chmod 666 /dev/fuse
- sudo chown root:$USER /etc/fuse.conf
- go run build/ci.go install
- go run build/ci.go test -coverage -vet -misspell
- os: osx
go: 1.8
sudo: required
script:
- brew update
- brew install caskroom/cask/brew-cask
- brew cask install osxfuse
- go run build/ci.go install
- go run build/ci.go test -coverage -vet -misspell
......
......@@ -173,6 +173,20 @@ func doInstall(cmdline []string) {
if flag.NArg() > 0 {
packages = flag.Args()
}
// Resolve ./... manually and remove vendor/bazil/fuse (fuse is not in windows)
out, err := goTool("list", "./...").CombinedOutput()
if err != nil {
log.Fatalf("package listing failed: %v\n%s", err, string(out))
}
packages = []string{}
for _, line := range strings.Split(string(out), "\n") {
if !strings.Contains(line, "vendor") {
packages = append(packages, strings.TrimSpace(line))
}
}
if *arch == "" || *arch == runtime.GOARCH {
goinstall := goTool("install", buildFlags(env)...)
goinstall.Args = append(goinstall.Args, "-v")
......
......@@ -122,7 +122,7 @@ func init() {
// Override flag defaults so bzzd can run alongside geth.
utils.ListenPortFlag.Value = 30399
utils.IPCPathFlag.Value = utils.DirectoryString{Value: "bzzd.ipc"}
utils.IPCApiFlag.Value = "admin, bzz, chequebook, debug, rpc, web3"
utils.IPCApiFlag.Value = "admin, bzz, chequebook, debug, rpc, swarmfs, web3"
// Set up the cli app.
app.Action = bzzd
......
......@@ -27,9 +27,12 @@ var Modules = map[string]string{
"personal": Personal_JS,
"rpc": RPC_JS,
"shh": Shh_JS,
"swarmfs": SWARMFS_JS,
"txpool": TxPool_JS,
}
const Chequebook_JS = `
web3._extend({
property: 'chequebook',
......@@ -486,6 +489,32 @@ web3._extend({
]
});
`
const SWARMFS_JS = `
web3._extend({
property: 'swarmfs',
methods:
[
new web3._extend.Method({
name: 'mount',
call: 'swarmfs_mount',
params: 2,
inputFormatter: [null,null]
}),
new web3._extend.Method({
name: 'unmount',
call: 'swarmfs_unmount',
params: 1,
inputFormatter: [null]
}),
new web3._extend.Method({
name: 'listmounts',
call: 'swarmfs_listmounts',
params: 0,
inputFormatter: []
})
]
});
`
const TxPool_JS = `
web3._extend({
......
// Copyright 2017 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
// +build !windows
package api
import (
"io"
"os"
"bazil.org/fuse"
"bazil.org/fuse/fs"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/swarm/storage"
"golang.org/x/net/context"
)
// Data structures used for Fuse filesystem, serving directories and serving files to Fuse driver
type FS struct {
root *Dir
}
type Dir struct {
inode uint64
name string
path string
directories []*Dir
files []*File
}
type File struct {
inode uint64
name string
path string
key storage.Key
swarmApi *Api
fileSize uint64
reader storage.LazySectionReader
}
// Functions which satisfy the Fuse File System requests
func (filesystem *FS) Root() (fs.Node, error) {
return filesystem.root, nil
}
func (directory *Dir) Attr(ctx context.Context, a *fuse.Attr) error {
a.Inode = directory.inode
//TODO: need to get permission as argument
a.Mode = os.ModeDir | 0500
a.Uid = uint32(os.Getuid())
a.Gid = uint32(os.Getegid())
return nil
}
func (directory *Dir) Lookup(ctx context.Context, name string) (fs.Node, error) {
if directory.files != nil {
for _, n := range directory.files {
if n.name == name {
return n, nil
}
}
}
if directory.directories != nil {
for _, n := range directory.directories {
if n.name == name {
return n, nil
}
}
}
return nil, fuse.ENOENT
}
func (d *Dir) ReadDirAll(ctx context.Context) ([]fuse.Dirent, error) {
var children []fuse.Dirent
if d.files != nil {
for _, file := range d.files {
children = append(children, fuse.Dirent{Inode: file.inode, Type: fuse.DT_File, Name: file.name})
}
}
if d.directories != nil {
for _, dir := range d.directories {
children = append(children, fuse.Dirent{Inode: dir.inode, Type: fuse.DT_Dir, Name: dir.name})
}
}
return children, nil
}
func (file *File) Attr(ctx context.Context, a *fuse.Attr) error {
a.Inode = file.inode
//TODO: need to get permission as argument
a.Mode = 0500
a.Uid = uint32(os.Getuid())
a.Gid = uint32(os.Getegid())
reader := file.swarmApi.Retrieve(file.key)
quitC := make(chan bool)
size, err := reader.Size(quitC)
if err != nil {
log.Warn("Couldnt file size of file %s : %v", file.path, err)
a.Size = uint64(0)
}
a.Size = uint64(size)
file.fileSize = a.Size
return nil
}
var _ = fs.HandleReader(&File{})
func (file *File) Read(ctx context.Context, req *fuse.ReadRequest, resp *fuse.ReadResponse) error {
buf := make([]byte, req.Size)
reader := file.swarmApi.Retrieve(file.key)
n, err := reader.ReadAt(buf, req.Offset)
if err == io.ErrUnexpectedEOF || err == io.EOF {
err = nil
}
resp.Data = buf[:n]
return err
}
// Copyright 2017 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package api
import (
"time"
"sync"
)
const (
Swarmfs_Version = "0.1"
mountTimeout = time.Second * 5
maxFuseMounts = 5
)
type SwarmFS struct {
swarmApi *Api
activeMounts map[string]*MountInfo
activeLock *sync.RWMutex
}
func NewSwarmFS(api *Api) *SwarmFS {
swarmfs := &SwarmFS{
swarmApi: api,
activeLock: &sync.RWMutex{},
activeMounts: map[string]*MountInfo{},
}
return swarmfs
}
// Copyright 2017 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
// +build linux darwin
package api
import (
"path/filepath"
"fmt"
"strings"
"time"
"github.com/ethereum/go-ethereum/swarm/storage"
"bazil.org/fuse"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/common"
"bazil.org/fuse/fs"
"sync"
)
var (
inode uint64 = 1
inodeLock sync.RWMutex
)
// information about every active mount
type MountInfo struct {
mountPoint string
manifestHash string
resolvedKey storage.Key
rootDir *Dir
fuseConnection *fuse.Conn
}
// Inode numbers need to be unique, they are used for caching inside fuse
func NewInode() uint64 {
inodeLock.Lock()
defer inodeLock.Unlock()
inode += 1
return inode
}
func (self *SwarmFS) Mount(mhash, mountpoint string) (string, error) {
self.activeLock.Lock()
defer self.activeLock.Unlock()
noOfActiveMounts := len(self.activeMounts)
if noOfActiveMounts >= maxFuseMounts {
err := fmt.Errorf("Max mount count reached. Cannot mount %s ", mountpoint)
log.Warn(err.Error())
return err.Error(), err
}
cleanedMountPoint, err := filepath.Abs(filepath.Clean(mountpoint))
if err != nil {
return err.Error(), err
}
if _, ok := self.activeMounts[cleanedMountPoint]; ok {
err := fmt.Errorf("Mountpoint %s already mounted.", cleanedMountPoint)
log.Warn(err.Error())
return err.Error(), err
}
log.Info(fmt.Sprintf("Attempting to mount %s ", cleanedMountPoint))
key, _, path, err := self.swarmApi.parseAndResolve(mhash, true)
if err != nil {
errStr := fmt.Sprintf("Could not resolve %s : %v", mhash, err)
log.Warn(errStr)
return errStr, err
}
if len(path) > 0 {
path += "/"
}
quitC := make(chan bool)
trie, err := loadManifest(self.swarmApi.dpa, key, quitC)
if err != nil {
errStr := fmt.Sprintf("fs.Download: loadManifestTrie error: %v", err)
log.Warn(errStr)
return errStr, err
}
dirTree := map[string]*Dir{}
rootDir := &Dir{
inode: NewInode(),
name: "root",
directories: nil,
files: nil,
}
dirTree["root"] = rootDir
err = trie.listWithPrefix(path, quitC, func(entry *manifestTrieEntry, suffix string) {
key = common.Hex2Bytes(entry.Hash)
fullpath := "/" + suffix
basepath := filepath.Dir(fullpath)
filename := filepath.Base(fullpath)
parentDir := rootDir
dirUntilNow := ""
paths := strings.Split(basepath, "/")
for i := range paths {
if paths[i] != "" {
thisDir := paths[i]
dirUntilNow = dirUntilNow + "/" + thisDir
if _, ok := dirTree[dirUntilNow]; !ok {
dirTree[dirUntilNow] = &Dir{
inode: NewInode(),
name: thisDir,
path: dirUntilNow,
directories: nil,
files: nil,
}
parentDir.directories = append(parentDir.directories, dirTree[dirUntilNow])
parentDir = dirTree[dirUntilNow]
} else {
parentDir = dirTree[dirUntilNow]
}
}
}
thisFile := &File{
inode: NewInode(),
name: filename,
path: fullpath,
key: key,
swarmApi: self.swarmApi,
}
parentDir.files = append(parentDir.files, thisFile)
})
fconn, err := fuse.Mount(cleanedMountPoint, fuse.FSName("swarmfs"), fuse.VolumeName(mhash))
if err != nil {
fuse.Unmount(cleanedMountPoint)
errStr := fmt.Sprintf("Mounting %s encountered error: %v", cleanedMountPoint, err)
log.Warn(errStr)
return errStr, err
}
mounterr := make(chan error, 1)
go func() {
log.Info(fmt.Sprintf("Serving %s at %s", mhash, cleanedMountPoint))
filesys := &FS{root: rootDir}
if err := fs.Serve(fconn, filesys); err != nil {
log.Warn(fmt.Sprintf("Could not Serve FS error: %v", err))
}
}()
// Check if the mount process has an error to report.
select {
case <-time.After(mountTimeout):
err := fmt.Errorf("Mounting %s timed out.", cleanedMountPoint)
log.Warn(err.Error())
return err.Error(), err
case err := <-mounterr:
errStr := fmt.Sprintf("Mounting %s encountered error: %v", cleanedMountPoint, err)
log.Warn(errStr)
return errStr, err
case <-fconn.Ready:
log.Debug(fmt.Sprintf("Mounting connection succeeded for : %v", cleanedMountPoint))
}
//Assemble and Store the mount information for future use
mountInformation := &MountInfo{
mountPoint: cleanedMountPoint,
manifestHash: mhash,
resolvedKey: key,
rootDir: rootDir,
fuseConnection: fconn,
}
self.activeMounts[cleanedMountPoint] = mountInformation
succString := fmt.Sprintf("Mounting successful for %s", cleanedMountPoint)
log.Info(succString)
return succString, nil
}
func (self *SwarmFS) Unmount(mountpoint string) (string, error) {
self.activeLock.Lock()
defer self.activeLock.Unlock()
cleanedMountPoint, err := filepath.Abs(filepath.Clean(mountpoint))
if err != nil {
return err.Error(), err
}
// Get the mount information based on the mountpoint argument
mountInfo := self.activeMounts[cleanedMountPoint]
if mountInfo == nil || mountInfo.mountPoint != cleanedMountPoint {
err := fmt.Errorf("Could not find mount information for %s ", cleanedMountPoint)
log.Warn(err.Error())
return err.Error(), err
}
err = fuse.Unmount(cleanedMountPoint)
if err != nil {
//TODO: try forceful unmount if normal unmount fails
errStr := fmt.Sprintf("UnMount error: %v", err)
log.Warn(errStr)
return errStr, err
}
mountInfo.fuseConnection.Close()
//remove the mount information from the active map
delete(self.activeMounts, cleanedMountPoint)
succString := fmt.Sprintf("UnMounting %v succeeded", cleanedMountPoint)
log.Info(succString)
return succString, nil
}
func (self *SwarmFS) Listmounts() (string, error) {
self.activeLock.RLock()
defer self.activeLock.RUnlock()
var rows []string
for mp := range self.activeMounts {
mountInfo := self.activeMounts[mp]
rows = append(rows, fmt.Sprintf("Swarm Root: %s, Mount Point: %s ", mountInfo.manifestHash, mountInfo.mountPoint))
}
return strings.Join(rows, "\n"), nil
}
func (self *SwarmFS) Stop() bool {
for mp := range self.activeMounts {
mountInfo := self.activeMounts[mp]
self.Unmount(mountInfo.mountPoint)
}
return true
}
// Copyright 2016 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
// +build linux darwin
package api
import (
"io/ioutil"
"os"
"path/filepath"
"testing"
)
var testUploadDir, _ = ioutil.TempDir(os.TempDir(), "fuse-source")
var testMountDir, _ = ioutil.TempDir(os.TempDir(), "fuse-dest")
func testFuseFileSystem(t *testing.T, f func(*FileSystem)) {
testApi(t, func(api *Api) {
f(NewFileSystem(api))
})
}
func createTestFiles(t *testing.T, files []string) {
os.RemoveAll(testUploadDir)
os.RemoveAll(testMountDir)
defer os.MkdirAll(testMountDir, 0777)
for f := range files {
actualPath := filepath.Join(testUploadDir, files[f])
filePath := filepath.Dir(actualPath)
err := os.MkdirAll(filePath, 0777)
if err != nil {
t.Fatalf("Error creating directory '%v' : %v", filePath, err)
}
_, err1 := os.OpenFile(actualPath, os.O_RDONLY|os.O_CREATE, 0666)
if err1 != nil {
t.Fatalf("Error creating file %v: %v", actualPath, err1)
}
}
}
func compareFiles(t *testing.T, files []string) {
for f := range files {
sourceFile := filepath.Join(testUploadDir, files[f])
destinationFile := filepath.Join(testMountDir, files[f])
sfinfo, err := os.Stat(sourceFile)
if err != nil {
t.Fatalf("Source file %v missing in mount: %v", files[f], err)
}
dfinfo, err := os.Stat(destinationFile)
if err != nil {
t.Fatalf("Destination file %v missing in mount: %v", files[f], err)
}
if sfinfo.Size() != dfinfo.Size() {
t.Fatalf("Size mismatch source (%v) vs destination(%v)", sfinfo.Size(), dfinfo.Size())
}
if dfinfo.Mode().Perm().String() != "-r-x------" {
t.Fatalf("Permission is not 0500for file: %v", err)
}
}
}
func doHashTest(fs *FileSystem, t *testing.T, ensName string, files ...string) {
createTestFiles(t, files)
bzzhash, err := fs.Upload(testUploadDir, "")
if err != nil {
t.Fatalf("Error uploading directory %v: %v", testUploadDir, err)
}
swarmfs := NewSwarmFS(fs.api)
_ ,err1 := swarmfs.Mount(bzzhash, testMountDir)
if err1 != nil {
t.Fatalf("Error mounting hash %v: %v", bzzhash, err)
}
compareFiles(t, files)
_, err2 := swarmfs.Unmount(testMountDir)
if err2 != nil {
t.Fatalf("Error unmounting path %v: %v", testMountDir, err)
}
swarmfs.Stop()
}
// mounting with manifest Hash
func TestFuseMountingScenarios(t *testing.T) {
testFuseFileSystem(t, func(fs *FileSystem) {
//doHashTest(fs,t, "test","1.txt")
doHashTest(fs, t, "", "1.txt")
doHashTest(fs, t, "", "1.txt", "11.txt", "111.txt", "two/2.txt", "two/two/2.txt", "three/3.txt")
doHashTest(fs, t, "", "1/2/3/4/5/6/7/8/9/10/11/12/1.txt")
doHashTest(fs, t, "", "one/one.txt", "one.txt", "once/one.txt", "one/one/one.txt")
})
}
// Copyright 2017 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
// +build windows
package api
import (
"github.com/ethereum/go-ethereum/log"
)
// Dummy struct and functions to satsfy windows build
type MountInfo struct {
}
func (self *SwarmFS) Mount(mhash, mountpoint string) error {
log.Info("Platform not supported")
return nil
}
func (self *SwarmFS) Unmount(mountpoint string) error {
log.Info("Platform not supported")
return nil
}
func (self *SwarmFS) Listmounts() (string, error) {
log.Info("Platform not supported")
return "",nil
}
func (self *SwarmFS) Stop() error {
log.Info("Platform not supported")
return nil
}
\ No newline at end of file
......@@ -54,6 +54,7 @@ type Swarm struct {
corsString string
swapEnabled bool
lstore *storage.LocalStore // local store, needs to store for releasing resources after node stopped
sfs *api.SwarmFS // need this to cleanup all the active mounts on node exit
}
type SwarmAPI struct {
......@@ -142,6 +143,9 @@ func NewSwarm(ctx *node.ServiceContext, backend chequebook.Backend, config *api.
// Manifests for Smart Hosting
log.Debug(fmt.Sprintf("-> Web3 virtual server API"))
self.sfs = api.NewSwarmFS(self.api)
log.Debug("-> Initializing Fuse file system")
return self, nil
}
......@@ -216,7 +220,7 @@ func (self *Swarm) Stop() error {
if self.lstore != nil {
self.lstore.DbStore.Close()
}
self.sfs.Stop()
return self.config.Save()
}
......@@ -240,6 +244,7 @@ func (self *Swarm) APIs() []rpc.API {
Service: api.NewStorage(self.api),
Public: true,
},
{
Namespace: "bzz",
Version: "0.1",
......@@ -264,6 +269,12 @@ func (self *Swarm) APIs() []rpc.API {
Service: chequebook.NewApi(self.config.Swap.Chequebook),
Public: false,
},
{
Namespace: "swarmfs",
Version: api.Swarmfs_Version,
Service: self.sfs,
Public: false,
},
// {Namespace, Version, api.NewAdmin(self), false},
}
}
......
Copyright (c) 2013-2015 Tommi Virtanen.
Copyright (c) 2009, 2011, 2012 The Go Authors.
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above
copyright notice, this list of conditions and the following disclaimer
in the documentation and/or other materials provided with the
distribution.
* Neither the name of Google Inc. nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
The following included software components have additional copyright
notices and license terms that may differ from the above.
File fuse.go:
// Adapted from Plan 9 from User Space's src/cmd/9pfuse/fuse.c,
// which carries this notice:
//
// The files in this directory are subject to the following license.
//
// The author of this software is Russ Cox.
//
// Copyright (c) 2006 Russ Cox
//
// Permission to use, copy, modify, and distribute this software for any
// purpose without fee is hereby granted, provided that this entire notice
// is included in all copies of any software which is or includes a copy
// or modification of this software and in all copies of the supporting
// documentation for such software.
//
// THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED
// WARRANTY. IN PARTICULAR, THE AUTHOR MAKES NO REPRESENTATION OR WARRANTY
// OF ANY KIND CONCERNING THE MERCHANTABILITY OF THIS SOFTWARE OR ITS
// FITNESS FOR ANY PARTICULAR PURPOSE.
File fuse_kernel.go:
// Derived from FUSE's fuse_kernel.h
/*
This file defines the kernel interface of FUSE
Copyright (C) 2001-2007 Miklos Szeredi <miklos@szeredi.hu>
This -- and only this -- header file may also be distributed under
the terms of the BSD Licence as follows:
Copyright (C) 2001-2007 Miklos Szeredi. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.
*/
bazil.org/fuse -- Filesystems in Go
===================================
`bazil.org/fuse` is a Go library for writing FUSE userspace
filesystems.
It is a from-scratch implementation of the kernel-userspace
communication protocol, and does not use the C library from the
project called FUSE. `bazil.org/fuse` embraces Go fully for safety and
ease of programming.
Here’s how to get going:
go get bazil.org/fuse
Website: http://bazil.org/fuse/
Github repository: https://github.com/bazil/fuse
API docs: http://godoc.org/bazil.org/fuse
Our thanks to Russ Cox for his fuse library, which this project is
based on.
package fuse
import "unsafe"
// buffer provides a mechanism for constructing a message from
// multiple segments.
type buffer []byte
// alloc allocates size bytes and returns a pointer to the new
// segment.
func (w *buffer) alloc(size uintptr) unsafe.Pointer {
s := int(size)
if len(*w)+s > cap(*w) {
old := *w
*w = make([]byte, len(*w), 2*cap(*w)+s)
copy(*w, old)
}
l := len(*w)
*w = (*w)[:l+s]
return unsafe.Pointer(&(*w)[l])
}
// reset clears out the contents of the buffer.
func (w *buffer) reset() {
for i := range (*w)[:cap(*w)] {
(*w)[i] = 0
}
*w = (*w)[:0]
}
func newBuffer(extra uintptr) buffer {
const hdrSize = unsafe.Sizeof(outHeader{})
buf := make(buffer, hdrSize, hdrSize+extra)
return buf
}
package fuse
import (
"runtime"
)
func stack() string {
buf := make([]byte, 1024)
return string(buf[:runtime.Stack(buf, false)])
}
func nop(msg interface{}) {}
// Debug is called to output debug messages, including protocol
// traces. The default behavior is to do nothing.
//
// The messages have human-friendly string representations and are
// safe to marshal to JSON.
//
// Implementations must not retain msg.
var Debug func(msg interface{}) = nop
package fuse
import (
"syscall"
)
const (
ENOATTR = Errno(syscall.ENOATTR)
)
const (
errNoXattr = ENOATTR
)
func init() {
errnoNames[errNoXattr] = "ENOATTR"
}
package fuse
import "syscall"
const (
ENOATTR = Errno(syscall.ENOATTR)
)
const (
errNoXattr = ENOATTR
)
func init() {
errnoNames[errNoXattr] = "ENOATTR"
}
package fuse
import (
"syscall"
)
const (
ENODATA = Errno(syscall.ENODATA)
)
const (
errNoXattr = ENODATA
)
func init() {
errnoNames[errNoXattr] = "ENODATA"
}
package fuse
// There is very little commonality in extended attribute errors
// across platforms.
//
// getxattr return value for "extended attribute does not exist" is
// ENOATTR on OS X, and ENODATA on Linux and apparently at least
// NetBSD. There may be a #define ENOATTR on Linux too, but the value
// is ENODATA in the actual syscalls. FreeBSD and OpenBSD have no
// ENODATA, only ENOATTR. ENOATTR is not in any of the standards,
// ENODATA exists but is only used for STREAMs.
//
// Each platform will define it a errNoXattr constant, and this file
// will enforce that it implements the right interfaces and hide the
// implementation.
//
// https://developer.apple.com/library/mac/documentation/Darwin/Reference/ManPages/man2/getxattr.2.html
// http://mail-index.netbsd.org/tech-kern/2012/04/30/msg013090.html
// http://mail-index.netbsd.org/tech-kern/2012/04/30/msg013097.html
// http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/errno.h.html
// http://www.freebsd.org/cgi/man.cgi?query=extattr_get_file&sektion=2
// http://nixdoc.net/man-pages/openbsd/man2/extattr_get_file.2.html
// ErrNoXattr is a platform-independent error value meaning the
// extended attribute was not found. It can be used to respond to
// GetxattrRequest and such.
const ErrNoXattr = errNoXattr
var _ error = ErrNoXattr
var _ Errno = ErrNoXattr
var _ ErrorNumber = ErrNoXattr
// FUSE service loop, for servers that wish to use it.
package fs // import "bazil.org/fuse/fs"
import (
"encoding/binary"
"fmt"
"hash/fnv"
"io"
"log"
"reflect"
"runtime"
"strings"
"sync"
"time"
"golang.org/x/net/context"
)
import (
"bytes"
"bazil.org/fuse"
"bazil.org/fuse/fuseutil"
)
const (
attrValidTime = 1 * time.Minute
entryValidTime = 1 * time.Minute
)
// TODO: FINISH DOCS
// An FS is the interface required of a file system.
//
// Other FUSE requests can be handled by implementing methods from the
// FS* interfaces, for example FSStatfser.
type FS interface {
// Root is called to obtain the Node for the file system root.
Root() (Node, error)
}
type FSStatfser interface {
// Statfs is called to obtain file system metadata.
// It should write that data to resp.
Statfs(ctx context.Context, req *fuse.StatfsRequest, resp *fuse.StatfsResponse) error
}
type FSDestroyer interface {
// Destroy is called when the file system is shutting down.
//
// Linux only sends this request for block device backed (fuseblk)
// filesystems, to allow them to flush writes to disk before the
// unmount completes.
Destroy()
}
type FSInodeGenerator interface {
// GenerateInode is called to pick a dynamic inode number when it
// would otherwise be 0.
//
// Not all filesystems bother tracking inodes, but FUSE requires
// the inode to be set, and fewer duplicates in general makes UNIX
// tools work better.
//
// Operations where the nodes may return 0 inodes include Getattr,
// Setattr and ReadDir.
//
// If FS does not implement FSInodeGenerator, GenerateDynamicInode
// is used.
//
// Implementing this is useful to e.g. constrain the range of
// inode values used for dynamic inodes.
GenerateInode(parentInode uint64, name string) uint64
}
// A Node is the interface required of a file or directory.
// See the documentation for type FS for general information
// pertaining to all methods.
//
// A Node must be usable as a map key, that is, it cannot be a
// function, map or slice.
//
// Other FUSE requests can be handled by implementing methods from the
// Node* interfaces, for example NodeOpener.
//
// Methods returning Node should take care to return the same Node
// when the result is logically the same instance. Without this, each
// Node will get a new NodeID, causing spurious cache invalidations,
// extra lookups and aliasing anomalies. This may not matter for a
// simple, read-only filesystem.
type Node interface {
// Attr fills attr with the standard metadata for the node.
//
// Fields with reasonable defaults are prepopulated. For example,
// all times are set to a fixed moment when the program started.
//
// If Inode is left as 0, a dynamic inode number is chosen.
//
// The result may be cached for the duration set in Valid.
Attr(ctx context.Context, attr *fuse.Attr) error
}
type NodeGetattrer interface {
// Getattr obtains the standard metadata for the receiver.
// It should store that metadata in resp.
//
// If this method is not implemented, the attributes will be
// generated based on Attr(), with zero values filled in.
Getattr(ctx context.Context, req *fuse.GetattrRequest, resp *fuse.GetattrResponse) error
}
type NodeSetattrer interface {
// Setattr sets the standard metadata for the receiver.
//
// Note, this is also used to communicate changes in the size of
// the file, outside of Writes.
//
// req.Valid is a bitmask of what fields are actually being set.
// For example, the method should not change the mode of the file
// unless req.Valid.Mode() is true.
Setattr(ctx context.Context, req *fuse.SetattrRequest, resp *fuse.SetattrResponse) error
}
type NodeSymlinker interface {
// Symlink creates a new symbolic link in the receiver, which must be a directory.
//
// TODO is the above true about directories?
Symlink(ctx context.Context, req *fuse.SymlinkRequest) (Node, error)
}
// This optional request will be called only for symbolic link nodes.
type NodeReadlinker interface {
// Readlink reads a symbolic link.
Readlink(ctx context.Context, req *fuse.ReadlinkRequest) (string, error)
}
type NodeLinker interface {
// Link creates a new directory entry in the receiver based on an
// existing Node. Receiver must be a directory.
Link(ctx context.Context, req *fuse.LinkRequest, old Node) (Node, error)
}
type NodeRemover interface {
// Remove removes the entry with the given name from
// the receiver, which must be a directory. The entry to be removed
// may correspond to a file (unlink) or to a directory (rmdir).
Remove(ctx context.Context, req *fuse.RemoveRequest) error
}
type NodeAccesser interface {
// Access checks whether the calling context has permission for
// the given operations on the receiver. If so, Access should
// return nil. If not, Access should return EPERM.
//
// Note that this call affects the result of the access(2) system
// call but not the open(2) system call. If Access is not
// implemented, the Node behaves as if it always returns nil
// (permission granted), relying on checks in Open instead.
Access(ctx context.Context, req *fuse.AccessRequest) error
}
type NodeStringLookuper interface {
// Lookup looks up a specific entry in the receiver,
// which must be a directory. Lookup should return a Node
// corresponding to the entry. If the name does not exist in
// the directory, Lookup should return ENOENT.
//
// Lookup need not to handle the names "." and "..".
Lookup(ctx context.Context, name string) (Node, error)
}
type NodeRequestLookuper interface {
// Lookup looks up a specific entry in the receiver.
// See NodeStringLookuper for more.
Lookup(ctx context.Context, req *fuse.LookupRequest, resp *fuse.LookupResponse) (Node, error)
}
type NodeMkdirer interface {
Mkdir(ctx context.Context, req *fuse.MkdirRequest) (Node, error)
}
type NodeOpener interface {
// Open opens the receiver. After a successful open, a client
// process has a file descriptor referring to this Handle.
//
// Open can also be also called on non-files. For example,
// directories are Opened for ReadDir or fchdir(2).
//
// If this method is not implemented, the open will always
// succeed, and the Node itself will be used as the Handle.
//
// XXX note about access. XXX OpenFlags.
Open(ctx context.Context, req *fuse.OpenRequest, resp *fuse.OpenResponse) (Handle, error)
}
type NodeCreater interface {
// Create creates a new directory entry in the receiver, which
// must be a directory.
Create(ctx context.Context, req *fuse.CreateRequest, resp *fuse.CreateResponse) (Node, Handle, error)
}
type NodeForgetter interface {
// Forget about this node. This node will not receive further
// method calls.
//
// Forget is not necessarily seen on unmount, as all nodes are
// implicitly forgotten as part part of the unmount.
Forget()
}
type NodeRenamer interface {
Rename(ctx context.Context, req *fuse.RenameRequest, newDir Node) error
}
type NodeMknoder interface {
Mknod(ctx context.Context, req *fuse.MknodRequest) (Node, error)
}
// TODO this should be on Handle not Node
type NodeFsyncer interface {
Fsync(ctx context.Context, req *fuse.FsyncRequest) error
}
type NodeGetxattrer interface {
// Getxattr gets an extended attribute by the given name from the
// node.
//
// If there is no xattr by that name, returns fuse.ErrNoXattr.
Getxattr(ctx context.Context, req *fuse.GetxattrRequest, resp *fuse.GetxattrResponse) error
}
type NodeListxattrer interface {
// Listxattr lists the extended attributes recorded for the node.
Listxattr(ctx context.Context, req *fuse.ListxattrRequest, resp *fuse.ListxattrResponse) error
}
type NodeSetxattrer interface {
// Setxattr sets an extended attribute with the given name and
// value for the node.
Setxattr(ctx context.Context, req *fuse.SetxattrRequest) error
}
type NodeRemovexattrer interface {
// Removexattr removes an extended attribute for the name.
//
// If there is no xattr by that name, returns fuse.ErrNoXattr.
Removexattr(ctx context.Context, req *fuse.RemovexattrRequest) error
}
var startTime = time.Now()
func nodeAttr(ctx context.Context, n Node, attr *fuse.Attr) error {
attr.Valid = attrValidTime
attr.Nlink = 1
attr.Atime = startTime
attr.Mtime = startTime
attr.Ctime = startTime
attr.Crtime = startTime
if err := n.Attr(ctx, attr); err != nil {
return err
}
return nil
}
// A Handle is the interface required of an opened file or directory.
// See the documentation for type FS for general information
// pertaining to all methods.
//
// Other FUSE requests can be handled by implementing methods from the
// Handle* interfaces. The most common to implement are HandleReader,
// HandleReadDirer, and HandleWriter.
//
// TODO implement methods: Getlk, Setlk, Setlkw
type Handle interface {
}
type HandleFlusher interface {
// Flush is called each time the file or directory is closed.
// Because there can be multiple file descriptors referring to a
// single opened file, Flush can be called multiple times.
Flush(ctx context.Context, req *fuse.FlushRequest) error
}
type HandleReadAller interface {
ReadAll(ctx context.Context) ([]byte, error)
}
type HandleReadDirAller interface {
ReadDirAll(ctx context.Context) ([]fuse.Dirent, error)
}
type HandleReader interface {
// Read requests to read data from the handle.
//
// There is a page cache in the kernel that normally submits only
// page-aligned reads spanning one or more pages. However, you
// should not rely on this. To see individual requests as
// submitted by the file system clients, set OpenDirectIO.
//
// Note that reads beyond the size of the file as reported by Attr
// are not even attempted (except in OpenDirectIO mode).
Read(ctx context.Context, req *fuse.ReadRequest, resp *fuse.ReadResponse) error
}
type HandleWriter interface {
// Write requests to write data into the handle at the given offset.
// Store the amount of data written in resp.Size.
//
// There is a writeback page cache in the kernel that normally submits
// only page-aligned writes spanning one or more pages. However,
// you should not rely on this. To see individual requests as
// submitted by the file system clients, set OpenDirectIO.
//
// Writes that grow the file are expected to update the file size
// (as seen through Attr). Note that file size changes are
// communicated also through Setattr.
Write(ctx context.Context, req *fuse.WriteRequest, resp *fuse.WriteResponse) error
}
type HandleReleaser interface {
Release(ctx context.Context, req *fuse.ReleaseRequest) error
}
type Config struct {
// Function to send debug log messages to. If nil, use fuse.Debug.
// Note that changing this or fuse.Debug may not affect existing
// calls to Serve.
//
// See fuse.Debug for the rules that log functions must follow.
Debug func(msg interface{})
// Function to put things into context for processing the request.
// The returned context must have ctx as its parent.
//
// Note that changing this may not affect existing calls to Serve.
//
// Must not retain req.
WithContext func(ctx context.Context, req fuse.Request) context.Context
}
// New returns a new FUSE server ready to serve this kernel FUSE
// connection.
//
// Config may be nil.
func New(conn *fuse.Conn, config *Config) *Server {
s := &Server{
conn: conn,
req: map[fuse.RequestID]*serveRequest{},
nodeRef: map[Node]fuse.NodeID{},
dynamicInode: GenerateDynamicInode,
}
if config != nil {
s.debug = config.Debug
s.context = config.WithContext
}
if s.debug == nil {
s.debug = fuse.Debug
}
return s
}
type Server struct {
// set in New
conn *fuse.Conn
debug func(msg interface{})
context func(ctx context.Context, req fuse.Request) context.Context
// set once at Serve time
fs FS
dynamicInode func(parent uint64, name string) uint64
// state, protected by meta
meta sync.Mutex
req map[fuse.RequestID]*serveRequest
node []*serveNode
nodeRef map[Node]fuse.NodeID
handle []*serveHandle
freeNode []fuse.NodeID
freeHandle []fuse.HandleID
nodeGen uint64
// Used to ensure worker goroutines finish before Serve returns
wg sync.WaitGroup
}
// Serve serves the FUSE connection by making calls to the methods
// of fs and the Nodes and Handles it makes available. It returns only
// when the connection has been closed or an unexpected error occurs.
func (s *Server) Serve(fs FS) error {
defer s.wg.Wait() // Wait for worker goroutines to complete before return
s.fs = fs
if dyn, ok := fs.(FSInodeGenerator); ok {
s.dynamicInode = dyn.GenerateInode
}
root, err := fs.Root()
if err != nil {
return fmt.Errorf("cannot obtain root node: %v", err)
}
// Recognize the root node if it's ever returned from Lookup,
// passed to Invalidate, etc.
s.nodeRef[root] = 1
s.node = append(s.node, nil, &serveNode{
inode: 1,
generation: s.nodeGen,
node: root,
refs: 1,
})
s.handle = append(s.handle, nil)
for {
req, err := s.conn.ReadRequest()
if err != nil {
if err == io.EOF {
break
}
return err
}
s.wg.Add(1)
go func() {
defer s.wg.Done()
s.serve(req)
}()
}
return nil
}
// Serve serves a FUSE connection with the default settings. See
// Server.Serve.
func Serve(c *fuse.Conn, fs FS) error {
server := New(c, nil)
return server.Serve(fs)
}
type nothing struct{}
type serveRequest struct {
Request fuse.Request
cancel func()
}
type serveNode struct {
inode uint64
generation uint64
node Node
refs uint64
// Delay freeing the NodeID until waitgroup is done. This allows
// using the NodeID for short periods of time without holding the
// Server.meta lock.
//
// Rules:
//
// - hold Server.meta while calling wg.Add, then unlock
// - do NOT try to reacquire Server.meta
wg sync.WaitGroup
}
func (sn *serveNode) attr(ctx context.Context, attr *fuse.Attr) error {
err := nodeAttr(ctx, sn.node, attr)
if attr.Inode == 0 {
attr.Inode = sn.inode
}
return err
}
type serveHandle struct {
handle Handle
readData []byte
nodeID fuse.NodeID
}
// NodeRef is deprecated. It remains here to decrease code churn on
// FUSE library users. You may remove it from your program now;
// returning the same Node values are now recognized automatically,
// without needing NodeRef.
type NodeRef struct{}
func (c *Server) saveNode(inode uint64, node Node) (id fuse.NodeID, gen uint64) {
c.meta.Lock()
defer c.meta.Unlock()
if id, ok := c.nodeRef[node]; ok {
sn := c.node[id]
sn.refs++
return id, sn.generation
}
sn := &serveNode{inode: inode, node: node, refs: 1}
if n := len(c.freeNode); n > 0 {
id = c.freeNode[n-1]
c.freeNode = c.freeNode[:n-1]
c.node[id] = sn
c.nodeGen++
} else {
id = fuse.NodeID(len(c.node))
c.node = append(c.node, sn)
}
sn.generation = c.nodeGen
c.nodeRef[node] = id
return id, sn.generation
}
func (c *Server) saveHandle(handle Handle, nodeID fuse.NodeID) (id fuse.HandleID) {
c.meta.Lock()
shandle := &serveHandle{handle: handle, nodeID: nodeID}
if n := len(c.freeHandle); n > 0 {
id = c.freeHandle[n-1]
c.freeHandle = c.freeHandle[:n-1]
c.handle[id] = shandle
} else {
id = fuse.HandleID(len(c.handle))
c.handle = append(c.handle, shandle)
}
c.meta.Unlock()
return
}
type nodeRefcountDropBug struct {
N uint64
Refs uint64
Node fuse.NodeID
}
func (n *nodeRefcountDropBug) String() string {
return fmt.Sprintf("bug: trying to drop %d of %d references to %v", n.N, n.Refs, n.Node)
}
func (c *Server) dropNode(id fuse.NodeID, n uint64) (forget bool) {
c.meta.Lock()
defer c.meta.Unlock()
snode := c.node[id]
if snode == nil {
// this should only happen if refcounts kernel<->us disagree
// *and* two ForgetRequests for the same node race each other;
// this indicates a bug somewhere
c.debug(nodeRefcountDropBug{N: n, Node: id})
// we may end up triggering Forget twice, but that's better
// than not even once, and that's the best we can do
return true
}
if n > snode.refs {
c.debug(nodeRefcountDropBug{N: n, Refs: snode.refs, Node: id})
n = snode.refs
}
snode.refs -= n
if snode.refs == 0 {
snode.wg.Wait()
c.node[id] = nil
delete(c.nodeRef, snode.node)
c.freeNode = append(c.freeNode, id)
return true
}
return false
}
func (c *Server) dropHandle(id fuse.HandleID) {
c.meta.Lock()
c.handle[id] = nil
c.freeHandle = append(c.freeHandle, id)
c.meta.Unlock()
}
type missingHandle struct {
Handle fuse.HandleID
MaxHandle fuse.HandleID
}
func (m missingHandle) String() string {
return fmt.Sprint("missing handle: ", m.Handle, m.MaxHandle)
}
// Returns nil for invalid handles.
func (c *Server) getHandle(id fuse.HandleID) (shandle *serveHandle) {
c.meta.Lock()
defer c.meta.Unlock()
if id < fuse.HandleID(len(c.handle)) {
shandle = c.handle[uint(id)]
}
if shandle == nil {
c.debug(missingHandle{
Handle: id,
MaxHandle: fuse.HandleID(len(c.handle)),
})
}
return
}
type request struct {
Op string
Request *fuse.Header
In interface{} `json:",omitempty"`
}
func (r request) String() string {
return fmt.Sprintf("<- %s", r.In)
}
type logResponseHeader struct {
ID fuse.RequestID
}
func (m logResponseHeader) String() string {
return fmt.Sprintf("ID=%v", m.ID)
}
type response struct {
Op string
Request logResponseHeader
Out interface{} `json:",omitempty"`
// Errno contains the errno value as a string, for example "EPERM".
Errno string `json:",omitempty"`
// Error may contain a free form error message.
Error string `json:",omitempty"`
}
func (r response) errstr() string {
s := r.Errno
if r.Error != "" {
// prefix the errno constant to the long form message
s = s + ": " + r.Error
}
return s
}
func (r response) String() string {
switch {
case r.Errno != "" && r.Out != nil:
return fmt.Sprintf("-> [%v] %v error=%s", r.Request, r.Out, r.errstr())
case r.Errno != "":
return fmt.Sprintf("-> [%v] %s error=%s", r.Request, r.Op, r.errstr())
case r.Out != nil:
// make sure (seemingly) empty values are readable
switch r.Out.(type) {
case string:
return fmt.Sprintf("-> [%v] %s %q", r.Request, r.Op, r.Out)
case []byte:
return fmt.Sprintf("-> [%v] %s [% x]", r.Request, r.Op, r.Out)
default:
return fmt.Sprintf("-> [%v] %v", r.Request, r.Out)
}
default:
return fmt.Sprintf("-> [%v] %s", r.Request, r.Op)
}
}
type notification struct {
Op string
Node fuse.NodeID
Out interface{} `json:",omitempty"`
Err string `json:",omitempty"`
}
func (n notification) String() string {
var buf bytes.Buffer
fmt.Fprintf(&buf, "=> %s %v", n.Op, n.Node)
if n.Out != nil {
// make sure (seemingly) empty values are readable
switch n.Out.(type) {
case string:
fmt.Fprintf(&buf, " %q", n.Out)
case []byte:
fmt.Fprintf(&buf, " [% x]", n.Out)
default:
fmt.Fprintf(&buf, " %s", n.Out)
}
}
if n.Err != "" {
fmt.Fprintf(&buf, " Err:%v", n.Err)
}
return buf.String()
}
type logMissingNode struct {
MaxNode fuse.NodeID
}
func opName(req fuse.Request) string {
t := reflect.Indirect(reflect.ValueOf(req)).Type()
s := t.Name()
s = strings.TrimSuffix(s, "Request")
return s
}
type logLinkRequestOldNodeNotFound struct {
Request *fuse.Header
In *fuse.LinkRequest
}
func (m *logLinkRequestOldNodeNotFound) String() string {
return fmt.Sprintf("In LinkRequest (request %v), node %d not found", m.Request.Hdr().ID, m.In.OldNode)
}
type renameNewDirNodeNotFound struct {
Request *fuse.Header
In *fuse.RenameRequest
}
func (m *renameNewDirNodeNotFound) String() string {
return fmt.Sprintf("In RenameRequest (request %v), node %d not found", m.Request.Hdr().ID, m.In.NewDir)
}
type handlerPanickedError struct {
Request interface{}
Err interface{}
}
var _ error = handlerPanickedError{}
func (h handlerPanickedError) Error() string {
return fmt.Sprintf("handler panicked: %v", h.Err)
}
var _ fuse.ErrorNumber = handlerPanickedError{}
func (h handlerPanickedError) Errno() fuse.Errno {
if err, ok := h.Err.(fuse.ErrorNumber); ok {
return err.Errno()
}
return fuse.DefaultErrno
}
// handlerTerminatedError happens when a handler terminates itself
// with runtime.Goexit. This is most commonly because of incorrect use
// of testing.TB.FailNow, typically via t.Fatal.
type handlerTerminatedError struct {
Request interface{}
}
var _ error = handlerTerminatedError{}
func (h handlerTerminatedError) Error() string {
return fmt.Sprintf("handler terminated (called runtime.Goexit)")
}
var _ fuse.ErrorNumber = handlerTerminatedError{}
func (h handlerTerminatedError) Errno() fuse.Errno {
return fuse.DefaultErrno
}
type handleNotReaderError struct {
handle Handle
}
var _ error = handleNotReaderError{}
func (e handleNotReaderError) Error() string {
return fmt.Sprintf("handle has no Read: %T", e.handle)
}
var _ fuse.ErrorNumber = handleNotReaderError{}
func (e handleNotReaderError) Errno() fuse.Errno {
return fuse.ENOTSUP
}
func initLookupResponse(s *fuse.LookupResponse) {
s.EntryValid = entryValidTime
}
func (c *Server) serve(r fuse.Request) {
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
parentCtx := ctx
if c.context != nil {
ctx = c.context(ctx, r)
}
req := &serveRequest{Request: r, cancel: cancel}
c.debug(request{
Op: opName(r),
Request: r.Hdr(),
In: r,
})
var node Node
var snode *serveNode
c.meta.Lock()
hdr := r.Hdr()
if id := hdr.Node; id != 0 {
if id < fuse.NodeID(len(c.node)) {
snode = c.node[uint(id)]
}
if snode == nil {
c.meta.Unlock()
c.debug(response{
Op: opName(r),
Request: logResponseHeader{ID: hdr.ID},
Error: fuse.ESTALE.ErrnoName(),
// this is the only place that sets both Error and
// Out; not sure if i want to do that; might get rid
// of len(c.node) things altogether
Out: logMissingNode{
MaxNode: fuse.NodeID(len(c.node)),
},
})
r.RespondError(fuse.ESTALE)
return
}
node = snode.node
}
if c.req[hdr.ID] != nil {
// This happens with OSXFUSE. Assume it's okay and
// that we'll never see an interrupt for this one.
// Otherwise everything wedges. TODO: Report to OSXFUSE?
//
// TODO this might have been because of missing done() calls
} else {
c.req[hdr.ID] = req
}
c.meta.Unlock()
// Call this before responding.
// After responding is too late: we might get another request
// with the same ID and be very confused.
done := func(resp interface{}) {
msg := response{
Op: opName(r),
Request: logResponseHeader{ID: hdr.ID},
}
if err, ok := resp.(error); ok {
msg.Error = err.Error()
if ferr, ok := err.(fuse.ErrorNumber); ok {
errno := ferr.Errno()
msg.Errno = errno.ErrnoName()
if errno == err {
// it's just a fuse.Errno with no extra detail;
// skip the textual message for log readability
msg.Error = ""
}
} else {
msg.Errno = fuse.DefaultErrno.ErrnoName()
}
} else {
msg.Out = resp
}
c.debug(msg)
c.meta.Lock()
delete(c.req, hdr.ID)
c.meta.Unlock()
}
var responded bool
defer func() {
if rec := recover(); rec != nil {
const size = 1 << 16
buf := make([]byte, size)
n := runtime.Stack(buf, false)
buf = buf[:n]
log.Printf("fuse: panic in handler for %v: %v\n%s", r, rec, buf)
err := handlerPanickedError{
Request: r,
Err: rec,
}
done(err)
r.RespondError(err)
return
}
if !responded {
err := handlerTerminatedError{
Request: r,
}
done(err)
r.RespondError(err)
}
}()
if err := c.handleRequest(ctx, node, snode, r, done); err != nil {
if err == context.Canceled {
select {
case <-parentCtx.Done():
// We canceled the parent context because of an
// incoming interrupt request, so return EINTR
// to trigger the right behavior in the client app.
//
// Only do this when it's the parent context that was
// canceled, not a context controlled by the program
// using this library, so we don't return EINTR too
// eagerly -- it might cause busy loops.
//
// Decent write-up on role of EINTR:
// http://250bpm.com/blog:12
err = fuse.EINTR
default:
// nothing
}
}
done(err)
r.RespondError(err)
}
// disarm runtime.Goexit protection
responded = true
}
// handleRequest will either a) call done(s) and r.Respond(s) OR b) return an error.
func (c *Server) handleRequest(ctx context.Context, node Node, snode *serveNode, r fuse.Request, done func(resp interface{})) error {
switch r := r.(type) {
default:
// Note: To FUSE, ENOSYS means "this server never implements this request."
// It would be inappropriate to return ENOSYS for other operations in this
// switch that might only be unavailable in some contexts, not all.
return fuse.ENOSYS
case *fuse.StatfsRequest:
s := &fuse.StatfsResponse{}
if fs, ok := c.fs.(FSStatfser); ok {
if err := fs.Statfs(ctx, r, s); err != nil {
return err
}
}
done(s)
r.Respond(s)
return nil
// Node operations.
case *fuse.GetattrRequest:
s := &fuse.GetattrResponse{}
if n, ok := node.(NodeGetattrer); ok {
if err := n.Getattr(ctx, r, s); err != nil {
return err
}
} else {
if err := snode.attr(ctx, &s.Attr); err != nil {
return err
}
}
done(s)
r.Respond(s)
return nil
case *fuse.SetattrRequest:
s := &fuse.SetattrResponse{}
if n, ok := node.(NodeSetattrer); ok {
if err := n.Setattr(ctx, r, s); err != nil {
return err
}
}
if err := snode.attr(ctx, &s.Attr); err != nil {
return err
}
done(s)
r.Respond(s)
return nil
case *fuse.SymlinkRequest:
s := &fuse.SymlinkResponse{}
initLookupResponse(&s.LookupResponse)
n, ok := node.(NodeSymlinker)
if !ok {
return fuse.EIO // XXX or EPERM like Mkdir?
}
n2, err := n.Symlink(ctx, r)
if err != nil {
return err
}
if err := c.saveLookup(ctx, &s.LookupResponse, snode, r.NewName, n2); err != nil {
return err
}
done(s)
r.Respond(s)
return nil
case *fuse.ReadlinkRequest:
n, ok := node.(NodeReadlinker)
if !ok {
return fuse.EIO /// XXX or EPERM?
}
target, err := n.Readlink(ctx, r)
if err != nil {
return err
}
done(target)
r.Respond(target)
return nil
case *fuse.LinkRequest:
n, ok := node.(NodeLinker)
if !ok {
return fuse.EIO /// XXX or EPERM?
}
c.meta.Lock()
var oldNode *serveNode
if int(r.OldNode) < len(c.node) {
oldNode = c.node[r.OldNode]
}
c.meta.Unlock()
if oldNode == nil {
c.debug(logLinkRequestOldNodeNotFound{
Request: r.Hdr(),
In: r,
})
return fuse.EIO
}
n2, err := n.Link(ctx, r, oldNode.node)
if err != nil {
return err
}
s := &fuse.LookupResponse{}
initLookupResponse(s)
if err := c.saveLookup(ctx, s, snode, r.NewName, n2); err != nil {
return err
}
done(s)
r.Respond(s)
return nil
case *fuse.RemoveRequest:
n, ok := node.(NodeRemover)
if !ok {
return fuse.EIO /// XXX or EPERM?
}
err := n.Remove(ctx, r)
if err != nil {
return err
}
done(nil)
r.Respond()
return nil
case *fuse.AccessRequest:
if n, ok := node.(NodeAccesser); ok {
if err := n.Access(ctx, r); err != nil {
return err
}
}
done(nil)
r.Respond()
return nil
case *fuse.LookupRequest:
var n2 Node
var err error
s := &fuse.LookupResponse{}
initLookupResponse(s)
if n, ok := node.(NodeStringLookuper); ok {
n2, err = n.Lookup(ctx, r.Name)
} else if n, ok := node.(NodeRequestLookuper); ok {
n2, err = n.Lookup(ctx, r, s)
} else {
return fuse.ENOENT
}
if err != nil {
return err
}
if err := c.saveLookup(ctx, s, snode, r.Name, n2); err != nil {
return err
}
done(s)
r.Respond(s)
return nil
case *fuse.MkdirRequest:
s := &fuse.MkdirResponse{}
initLookupResponse(&s.LookupResponse)
n, ok := node.(NodeMkdirer)
if !ok {
return fuse.EPERM
}
n2, err := n.Mkdir(ctx, r)
if err != nil {
return err
}
if err := c.saveLookup(ctx, &s.LookupResponse, snode, r.Name, n2); err != nil {
return err
}
done(s)
r.Respond(s)
return nil
case *fuse.OpenRequest:
s := &fuse.OpenResponse{}
var h2 Handle
if n, ok := node.(NodeOpener); ok {
hh, err := n.Open(ctx, r, s)
if err != nil {
return err
}
h2 = hh
} else {
h2 = node
}
s.Handle = c.saveHandle(h2, r.Hdr().Node)
done(s)
r.Respond(s)
return nil
case *fuse.CreateRequest:
n, ok := node.(NodeCreater)
if !ok {
// If we send back ENOSYS, FUSE will try mknod+open.
return fuse.EPERM
}
s := &fuse.CreateResponse{OpenResponse: fuse.OpenResponse{}}
initLookupResponse(&s.LookupResponse)
n2, h2, err := n.Create(ctx, r, s)
if err != nil {
return err
}
if err := c.saveLookup(ctx, &s.LookupResponse, snode, r.Name, n2); err != nil {
return err
}
s.Handle = c.saveHandle(h2, r.Hdr().Node)
done(s)
r.Respond(s)
return nil
case *fuse.GetxattrRequest:
n, ok := node.(NodeGetxattrer)
if !ok {
return fuse.ENOTSUP
}
s := &fuse.GetxattrResponse{}
err := n.Getxattr(ctx, r, s)
if err != nil {
return err
}
if r.Size != 0 && uint64(len(s.Xattr)) > uint64(r.Size) {
return fuse.ERANGE
}
done(s)
r.Respond(s)
return nil
case *fuse.ListxattrRequest:
n, ok := node.(NodeListxattrer)
if !ok {
return fuse.ENOTSUP
}
s := &fuse.ListxattrResponse{}
err := n.Listxattr(ctx, r, s)
if err != nil {
return err
}
if r.Size != 0 && uint64(len(s.Xattr)) > uint64(r.Size) {
return fuse.ERANGE
}
done(s)
r.Respond(s)
return nil
case *fuse.SetxattrRequest:
n, ok := node.(NodeSetxattrer)
if !ok {
return fuse.ENOTSUP
}
err := n.Setxattr(ctx, r)
if err != nil {
return err
}
done(nil)
r.Respond()
return nil
case *fuse.RemovexattrRequest:
n, ok := node.(NodeRemovexattrer)
if !ok {
return fuse.ENOTSUP
}
err := n.Removexattr(ctx, r)
if err != nil {
return err
}
done(nil)
r.Respond()
return nil
case *fuse.ForgetRequest:
forget := c.dropNode(r.Hdr().Node, r.N)
if forget {
n, ok := node.(NodeForgetter)
if ok {
n.Forget()
}
}
done(nil)
r.Respond()
return nil
// Handle operations.
case *fuse.ReadRequest:
shandle := c.getHandle(r.Handle)
if shandle == nil {
return fuse.ESTALE
}
handle := shandle.handle
s := &fuse.ReadResponse{Data: make([]byte, 0, r.Size)}
if r.Dir {
if h, ok := handle.(HandleReadDirAller); ok {
// detect rewinddir(3) or similar seek and refresh
// contents
if r.Offset == 0 {
shandle.readData = nil
}
if shandle.readData == nil {
dirs, err := h.ReadDirAll(ctx)
if err != nil {
return err
}
var data []byte
for _, dir := range dirs {
if dir.Inode == 0 {
dir.Inode = c.dynamicInode(snode.inode, dir.Name)
}
data = fuse.AppendDirent(data, dir)
}
shandle.readData = data
}
fuseutil.HandleRead(r, s, shandle.readData)
done(s)
r.Respond(s)
return nil
}
} else {
if h, ok := handle.(HandleReadAller); ok {
if shandle.readData == nil {
data, err := h.ReadAll(ctx)
if err != nil {
return err
}
if data == nil {
data = []byte{}
}
shandle.readData = data
}
fuseutil.HandleRead(r, s, shandle.readData)
done(s)
r.Respond(s)
return nil
}
h, ok := handle.(HandleReader)
if !ok {
err := handleNotReaderError{handle: handle}
return err
}
if err := h.Read(ctx, r, s); err != nil {
return err
}
}
done(s)
r.Respond(s)
return nil
case *fuse.WriteRequest:
shandle := c.getHandle(r.Handle)
if shandle == nil {
return fuse.ESTALE
}
s := &fuse.WriteResponse{}
if h, ok := shandle.handle.(HandleWriter); ok {
if err := h.Write(ctx, r, s); err != nil {
return err
}
done(s)
r.Respond(s)
return nil
}
return fuse.EIO
case *fuse.FlushRequest:
shandle := c.getHandle(r.Handle)
if shandle == nil {
return fuse.ESTALE
}
handle := shandle.handle
if h, ok := handle.(HandleFlusher); ok {
if err := h.Flush(ctx, r); err != nil {
return err
}
}
done(nil)
r.Respond()
return nil
case *fuse.ReleaseRequest:
shandle := c.getHandle(r.Handle)
if shandle == nil {
return fuse.ESTALE
}
handle := shandle.handle
// No matter what, release the handle.
c.dropHandle(r.Handle)
if h, ok := handle.(HandleReleaser); ok {
if err := h.Release(ctx, r); err != nil {
return err
}
}
done(nil)
r.Respond()
return nil
case *fuse.DestroyRequest:
if fs, ok := c.fs.(FSDestroyer); ok {
fs.Destroy()
}
done(nil)
r.Respond()
return nil
case *fuse.RenameRequest:
c.meta.Lock()
var newDirNode *serveNode
if int(r.NewDir) < len(c.node) {
newDirNode = c.node[r.NewDir]
}
c.meta.Unlock()
if newDirNode == nil {
c.debug(renameNewDirNodeNotFound{
Request: r.Hdr(),
In: r,
})
return fuse.EIO
}
n, ok := node.(NodeRenamer)
if !ok {
return fuse.EIO // XXX or EPERM like Mkdir?
}
err := n.Rename(ctx, r, newDirNode.node)
if err != nil {
return err
}
done(nil)
r.Respond()
return nil
case *fuse.MknodRequest:
n, ok := node.(NodeMknoder)
if !ok {
return fuse.EIO
}
n2, err := n.Mknod(ctx, r)
if err != nil {
return err
}
s := &fuse.LookupResponse{}
initLookupResponse(s)
if err := c.saveLookup(ctx, s, snode, r.Name, n2); err != nil {
return err
}
done(s)
r.Respond(s)
return nil
case *fuse.FsyncRequest:
n, ok := node.(NodeFsyncer)
if !ok {
return fuse.EIO
}
err := n.Fsync(ctx, r)
if err != nil {
return err
}
done(nil)
r.Respond()
return nil
case *fuse.InterruptRequest:
c.meta.Lock()
ireq := c.req[r.IntrID]
if ireq != nil && ireq.cancel != nil {
ireq.cancel()
ireq.cancel = nil
}
c.meta.Unlock()
done(nil)
r.Respond()
return nil
/* case *FsyncdirRequest:
return ENOSYS
case *GetlkRequest, *SetlkRequest, *SetlkwRequest:
return ENOSYS
case *BmapRequest:
return ENOSYS
case *SetvolnameRequest, *GetxtimesRequest, *ExchangeRequest:
return ENOSYS
*/
}
panic("not reached")
}
func (c *Server) saveLookup(ctx context.Context, s *fuse.LookupResponse, snode *serveNode, elem string, n2 Node) error {
if err := nodeAttr(ctx, n2, &s.Attr); err != nil {
return err
}
if s.Attr.Inode == 0 {
s.Attr.Inode = c.dynamicInode(snode.inode, elem)
}
s.Node, s.Generation = c.saveNode(s.Attr.Inode, n2)
return nil
}
type invalidateNodeDetail struct {
Off int64
Size int64
}
func (i invalidateNodeDetail) String() string {
return fmt.Sprintf("Off:%d Size:%d", i.Off, i.Size)
}
func errstr(err error) string {
if err == nil {
return ""
}
return err.Error()
}
func (s *Server) invalidateNode(node Node, off int64, size int64) error {
s.meta.Lock()
id, ok := s.nodeRef[node]
if ok {
snode := s.node[id]
snode.wg.Add(1)
defer snode.wg.Done()
}
s.meta.Unlock()
if !ok {
// This is what the kernel would have said, if we had been
// able to send this message; it's not cached.
return fuse.ErrNotCached
}
// Delay logging until after we can record the error too. We
// consider a /dev/fuse write to be instantaneous enough to not
// need separate before and after messages.
err := s.conn.InvalidateNode(id, off, size)
s.debug(notification{
Op: "InvalidateNode",
Node: id,
Out: invalidateNodeDetail{
Off: off,
Size: size,
},
Err: errstr(err),
})
return err
}
// InvalidateNodeAttr invalidates the kernel cache of the attributes
// of node.
//
// Returns fuse.ErrNotCached if the kernel is not currently caching
// the node.
func (s *Server) InvalidateNodeAttr(node Node) error {
return s.invalidateNode(node, 0, 0)
}
// InvalidateNodeData invalidates the kernel cache of the attributes
// and data of node.
//
// Returns fuse.ErrNotCached if the kernel is not currently caching
// the node.
func (s *Server) InvalidateNodeData(node Node) error {
return s.invalidateNode(node, 0, -1)
}
// InvalidateNodeDataRange invalidates the kernel cache of the
// attributes and a range of the data of node.
//
// Returns fuse.ErrNotCached if the kernel is not currently caching
// the node.
func (s *Server) InvalidateNodeDataRange(node Node, off int64, size int64) error {
return s.invalidateNode(node, off, size)
}
type invalidateEntryDetail struct {
Name string
}
func (i invalidateEntryDetail) String() string {
return fmt.Sprintf("%q", i.Name)
}
// InvalidateEntry invalidates the kernel cache of the directory entry
// identified by parent node and entry basename.
//
// Kernel may or may not cache directory listings. To invalidate
// those, use InvalidateNode to invalidate all of the data for a
// directory. (As of 2015-06, Linux FUSE does not cache directory
// listings.)
//
// Returns ErrNotCached if the kernel is not currently caching the
// node.
func (s *Server) InvalidateEntry(parent Node, name string) error {
s.meta.Lock()
id, ok := s.nodeRef[parent]
if ok {
snode := s.node[id]
snode.wg.Add(1)
defer snode.wg.Done()
}
s.meta.Unlock()
if !ok {
// This is what the kernel would have said, if we had been
// able to send this message; it's not cached.
return fuse.ErrNotCached
}
err := s.conn.InvalidateEntry(id, name)
s.debug(notification{
Op: "InvalidateEntry",
Node: id,
Out: invalidateEntryDetail{
Name: name,
},
Err: errstr(err),
})
return err
}
// DataHandle returns a read-only Handle that satisfies reads
// using the given data.
func DataHandle(data []byte) Handle {
return &dataHandle{data}
}
type dataHandle struct {
data []byte
}
func (d *dataHandle) ReadAll(ctx context.Context) ([]byte, error) {
return d.data, nil
}
// GenerateDynamicInode returns a dynamic inode.
//
// The parent inode and current entry name are used as the criteria
// for choosing a pseudorandom inode. This makes it likely the same
// entry will get the same inode on multiple runs.
func GenerateDynamicInode(parent uint64, name string) uint64 {
h := fnv.New64a()
var buf [8]byte
binary.LittleEndian.PutUint64(buf[:], parent)
_, _ = h.Write(buf[:])
_, _ = h.Write([]byte(name))
var inode uint64
for {
inode = h.Sum64()
if inode != 0 {
break
}
// there's a tiny probability that result is zero; change the
// input a little and try again
_, _ = h.Write([]byte{'x'})
}
return inode
}
// FUSE directory tree, for servers that wish to use it with the service loop.
package fs
import (
"os"
pathpkg "path"
"strings"
"golang.org/x/net/context"
)
import (
"bazil.org/fuse"
)
// A Tree implements a basic read-only directory tree for FUSE.
// The Nodes contained in it may still be writable.
type Tree struct {
tree
}
func (t *Tree) Root() (Node, error) {
return &t.tree, nil
}
// Add adds the path to the tree, resolving to the given node.
// If path or a prefix of path has already been added to the tree,
// Add panics.
//
// Add is only safe to call before starting to serve requests.
func (t *Tree) Add(path string, node Node) {
path = pathpkg.Clean("/" + path)[1:]
elems := strings.Split(path, "/")
dir := Node(&t.tree)
for i, elem := range elems {
dt, ok := dir.(*tree)
if !ok {
panic("fuse: Tree.Add for " + strings.Join(elems[:i], "/") + " and " + path)
}
n := dt.lookup(elem)
if n != nil {
if i+1 == len(elems) {
panic("fuse: Tree.Add for " + path + " conflicts with " + elem)
}
dir = n
} else {
if i+1 == len(elems) {
dt.add(elem, node)
} else {
dir = &tree{}
dt.add(elem, dir)
}
}
}
}
type treeDir struct {
name string
node Node
}
type tree struct {
dir []treeDir
}
func (t *tree) lookup(name string) Node {
for _, d := range t.dir {
if d.name == name {
return d.node
}
}
return nil
}
func (t *tree) add(name string, n Node) {
t.dir = append(t.dir, treeDir{name, n})
}
func (t *tree) Attr(ctx context.Context, a *fuse.Attr) error {
a.Mode = os.ModeDir | 0555
return nil
}
func (t *tree) Lookup(ctx context.Context, name string) (Node, error) {
n := t.lookup(name)
if n != nil {
return n, nil
}
return nil, fuse.ENOENT
}
func (t *tree) ReadDirAll(ctx context.Context) ([]fuse.Dirent, error) {
var out []fuse.Dirent
for _, d := range t.dir {
out = append(out, fuse.Dirent{Name: d.name})
}
return out, nil
}
// See the file LICENSE for copyright and licensing information.
// Adapted from Plan 9 from User Space's src/cmd/9pfuse/fuse.c,
// which carries this notice:
//
// The files in this directory are subject to the following license.
//
// The author of this software is Russ Cox.
//
// Copyright (c) 2006 Russ Cox
//
// Permission to use, copy, modify, and distribute this software for any
// purpose without fee is hereby granted, provided that this entire notice
// is included in all copies of any software which is or includes a copy
// or modification of this software and in all copies of the supporting
// documentation for such software.
//
// THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED
// WARRANTY. IN PARTICULAR, THE AUTHOR MAKES NO REPRESENTATION OR WARRANTY
// OF ANY KIND CONCERNING THE MERCHANTABILITY OF THIS SOFTWARE OR ITS
// FITNESS FOR ANY PARTICULAR PURPOSE.
// Package fuse enables writing FUSE file systems on Linux, OS X, and FreeBSD.
//
// On OS X, it requires OSXFUSE (http://osxfuse.github.com/).
//
// There are two approaches to writing a FUSE file system. The first is to speak
// the low-level message protocol, reading from a Conn using ReadRequest and
// writing using the various Respond methods. This approach is closest to
// the actual interaction with the kernel and can be the simplest one in contexts
// such as protocol translators.
//
// Servers of synthesized file systems tend to share common
// bookkeeping abstracted away by the second approach, which is to
// call fs.Serve to serve the FUSE protocol using an implementation of
// the service methods in the interfaces FS* (file system), Node* (file
// or directory), and Handle* (opened file or directory).
// There are a daunting number of such methods that can be written,
// but few are required.
// The specific methods are described in the documentation for those interfaces.
//
// The hellofs subdirectory contains a simple illustration of the fs.Serve approach.
//
// Service Methods
//
// The required and optional methods for the FS, Node, and Handle interfaces
// have the general form
//
// Op(ctx context.Context, req *OpRequest, resp *OpResponse) error
//
// where Op is the name of a FUSE operation. Op reads request
// parameters from req and writes results to resp. An operation whose
// only result is the error result omits the resp parameter.
//
// Multiple goroutines may call service methods simultaneously; the
// methods being called are responsible for appropriate
// synchronization.
//
// The operation must not hold on to the request or response,
// including any []byte fields such as WriteRequest.Data or
// SetxattrRequest.Xattr.
//
// Errors
//
// Operations can return errors. The FUSE interface can only
// communicate POSIX errno error numbers to file system clients, the
// message is not visible to file system clients. The returned error
// can implement ErrorNumber to control the errno returned. Without
// ErrorNumber, a generic errno (EIO) is returned.
//
// Error messages will be visible in the debug log as part of the
// response.
//
// Interrupted Operations
//
// In some file systems, some operations
// may take an undetermined amount of time. For example, a Read waiting for
// a network message or a matching Write might wait indefinitely. If the request
// is cancelled and no longer needed, the context will be cancelled.
// Blocking operations should select on a receive from ctx.Done() and attempt to
// abort the operation early if the receive succeeds (meaning the channel is closed).
// To indicate that the operation failed because it was aborted, return fuse.EINTR.
//
// If an operation does not block for an indefinite amount of time, supporting
// cancellation is not necessary.
//
// Authentication
//
// All requests types embed a Header, meaning that the method can
// inspect req.Pid, req.Uid, and req.Gid as necessary to implement
// permission checking. The kernel FUSE layer normally prevents other
// users from accessing the FUSE file system (to change this, see
// AllowOther, AllowRoot), but does not enforce access modes (to
// change this, see DefaultPermissions).
//
// Mount Options
//
// Behavior and metadata of the mounted file system can be changed by
// passing MountOption values to Mount.
//
package fuse // import "bazil.org/fuse"
import (
"bytes"
"encoding/json"
"errors"
"fmt"
"io"
"os"
"sync"
"syscall"
"time"
"unsafe"
)
// A Conn represents a connection to a mounted FUSE file system.
type Conn struct {
// Ready is closed when the mount is complete or has failed.
Ready <-chan struct{}
// MountError stores any error from the mount process. Only valid
// after Ready is closed.
MountError error
// File handle for kernel communication. Only safe to access if
// rio or wio is held.
dev *os.File
wio sync.RWMutex
rio sync.RWMutex
// Protocol version negotiated with InitRequest/InitResponse.
proto Protocol
}
// MountpointDoesNotExistError is an error returned when the
// mountpoint does not exist.
type MountpointDoesNotExistError struct {
Path string
}
var _ error = (*MountpointDoesNotExistError)(nil)
func (e *MountpointDoesNotExistError) Error() string {
return fmt.Sprintf("mountpoint does not exist: %v", e.Path)
}
// Mount mounts a new FUSE connection on the named directory
// and returns a connection for reading and writing FUSE messages.
//
// After a successful return, caller must call Close to free
// resources.
//
// Even on successful return, the new mount is not guaranteed to be
// visible until after Conn.Ready is closed. See Conn.MountError for
// possible errors. Incoming requests on Conn must be served to make
// progress.
func Mount(dir string, options ...MountOption) (*Conn, error) {
conf := mountConfig{
options: make(map[string]string),
}
for _, option := range options {
if err := option(&conf); err != nil {
return nil, err
}
}
ready := make(chan struct{}, 1)
c := &Conn{
Ready: ready,
}
f, err := mount(dir, &conf, ready, &c.MountError)
if err != nil {
return nil, err
}
c.dev = f
if err := initMount(c, &conf); err != nil {
c.Close()
if err == ErrClosedWithoutInit {
// see if we can provide a better error
<-c.Ready
if err := c.MountError; err != nil {
return nil, err
}
}
return nil, err
}
return c, nil
}
type OldVersionError struct {
Kernel Protocol
LibraryMin Protocol
}
func (e *OldVersionError) Error() string {
return fmt.Sprintf("kernel FUSE version is too old: %v < %v", e.Kernel, e.LibraryMin)
}
var (
ErrClosedWithoutInit = errors.New("fuse connection closed without init")
)
func initMount(c *Conn, conf *mountConfig) error {
req, err := c.ReadRequest()
if err != nil {
if err == io.EOF {
return ErrClosedWithoutInit
}
return err
}
r, ok := req.(*InitRequest)
if !ok {
return fmt.Errorf("missing init, got: %T", req)
}
min := Protocol{protoVersionMinMajor, protoVersionMinMinor}
if r.Kernel.LT(min) {
req.RespondError(Errno(syscall.EPROTO))
c.Close()
return &OldVersionError{
Kernel: r.Kernel,
LibraryMin: min,
}
}
proto := Protocol{protoVersionMaxMajor, protoVersionMaxMinor}
if r.Kernel.LT(proto) {
// Kernel doesn't support the latest version we have.
proto = r.Kernel
}
c.proto = proto
s := &InitResponse{
Library: proto,
MaxReadahead: conf.maxReadahead,
MaxWrite: maxWrite,
Flags: InitBigWrites | conf.initFlags,
}
r.Respond(s)
return nil
}
// A Request represents a single FUSE request received from the kernel.
// Use a type switch to determine the specific kind.
// A request of unrecognized type will have concrete type *Header.
type Request interface {
// Hdr returns the Header associated with this request.
Hdr() *Header
// RespondError responds to the request with the given error.
RespondError(error)
String() string
}
// A RequestID identifies an active FUSE request.
type RequestID uint64
func (r RequestID) String() string {
return fmt.Sprintf("%#x", uint64(r))
}
// A NodeID is a number identifying a directory or file.
// It must be unique among IDs returned in LookupResponses
// that have not yet been forgotten by ForgetRequests.
type NodeID uint64
func (n NodeID) String() string {
return fmt.Sprintf("%#x", uint64(n))
}
// A HandleID is a number identifying an open directory or file.
// It only needs to be unique while the directory or file is open.
type HandleID uint64
func (h HandleID) String() string {
return fmt.Sprintf("%#x", uint64(h))
}
// The RootID identifies the root directory of a FUSE file system.
const RootID NodeID = rootID
// A Header describes the basic information sent in every request.
type Header struct {
Conn *Conn `json:"-"` // connection this request was received on
ID RequestID // unique ID for request
Node NodeID // file or directory the request is about
Uid uint32 // user ID of process making request
Gid uint32 // group ID of process making request
Pid uint32 // process ID of process making request
// for returning to reqPool
msg *message
}
func (h *Header) String() string {
return fmt.Sprintf("ID=%v Node=%v Uid=%d Gid=%d Pid=%d", h.ID, h.Node, h.Uid, h.Gid, h.Pid)
}
func (h *Header) Hdr() *Header {
return h
}
func (h *Header) noResponse() {
putMessage(h.msg)
}
func (h *Header) respond(msg []byte) {
out := (*outHeader)(unsafe.Pointer(&msg[0]))
out.Unique = uint64(h.ID)
h.Conn.respond(msg)
putMessage(h.msg)
}
// An ErrorNumber is an error with a specific error number.
//
// Operations may return an error value that implements ErrorNumber to
// control what specific error number (errno) to return.
type ErrorNumber interface {
// Errno returns the the error number (errno) for this error.
Errno() Errno
}
const (
// ENOSYS indicates that the call is not supported.
ENOSYS = Errno(syscall.ENOSYS)
// ESTALE is used by Serve to respond to violations of the FUSE protocol.
ESTALE = Errno(syscall.ESTALE)
ENOENT = Errno(syscall.ENOENT)
EIO = Errno(syscall.EIO)
EPERM = Errno(syscall.EPERM)
// EINTR indicates request was interrupted by an InterruptRequest.
// See also fs.Intr.
EINTR = Errno(syscall.EINTR)
ERANGE = Errno(syscall.ERANGE)
ENOTSUP = Errno(syscall.ENOTSUP)
EEXIST = Errno(syscall.EEXIST)
)
// DefaultErrno is the errno used when error returned does not
// implement ErrorNumber.
const DefaultErrno = EIO
var errnoNames = map[Errno]string{
ENOSYS: "ENOSYS",
ESTALE: "ESTALE",
ENOENT: "ENOENT",
EIO: "EIO",
EPERM: "EPERM",
EINTR: "EINTR",
EEXIST: "EEXIST",
}
// Errno implements Error and ErrorNumber using a syscall.Errno.
type Errno syscall.Errno
var _ = ErrorNumber(Errno(0))
var _ = error(Errno(0))
func (e Errno) Errno() Errno {
return e
}
func (e Errno) String() string {
return syscall.Errno(e).Error()
}
func (e Errno) Error() string {
return syscall.Errno(e).Error()
}
// ErrnoName returns the short non-numeric identifier for this errno.
// For example, "EIO".
func (e Errno) ErrnoName() string {
s := errnoNames[e]
if s == "" {
s = fmt.Sprint(e.Errno())
}
return s
}
func (e Errno) MarshalText() ([]byte, error) {
s := e.ErrnoName()
return []byte(s), nil
}
func (h *Header) RespondError(err error) {
errno := DefaultErrno
if ferr, ok := err.(ErrorNumber); ok {
errno = ferr.Errno()
}
// FUSE uses negative errors!
// TODO: File bug report against OSXFUSE: positive error causes kernel panic.
buf := newBuffer(0)
hOut := (*outHeader)(unsafe.Pointer(&buf[0]))
hOut.Error = -int32(errno)
h.respond(buf)
}
// All requests read from the kernel, without data, are shorter than
// this.
var maxRequestSize = syscall.Getpagesize()
var bufSize = maxRequestSize + maxWrite
// reqPool is a pool of messages.
//
// Lifetime of a logical message is from getMessage to putMessage.
// getMessage is called by ReadRequest. putMessage is called by
// Conn.ReadRequest, Request.Respond, or Request.RespondError.
//
// Messages in the pool are guaranteed to have conn and off zeroed,
// buf allocated and len==bufSize, and hdr set.
var reqPool = sync.Pool{
New: allocMessage,
}
func allocMessage() interface{} {
m := &message{buf: make([]byte, bufSize)}
m.hdr = (*inHeader)(unsafe.Pointer(&m.buf[0]))
return m
}
func getMessage(c *Conn) *message {
m := reqPool.Get().(*message)
m.conn = c
return m
}
func putMessage(m *message) {
m.buf = m.buf[:bufSize]
m.conn = nil
m.off = 0
reqPool.Put(m)
}
// a message represents the bytes of a single FUSE message
type message struct {
conn *Conn
buf []byte // all bytes
hdr *inHeader // header
off int // offset for reading additional fields
}
func (m *message) len() uintptr {
return uintptr(len(m.buf) - m.off)
}
func (m *message) data() unsafe.Pointer {
var p unsafe.Pointer
if m.off < len(m.buf) {
p = unsafe.Pointer(&m.buf[m.off])
}
return p
}
func (m *message) bytes() []byte {
return m.buf[m.off:]
}
func (m *message) Header() Header {
h := m.hdr
return Header{
Conn: m.conn,
ID: RequestID(h.Unique),
Node: NodeID(h.Nodeid),
Uid: h.Uid,
Gid: h.Gid,
Pid: h.Pid,
msg: m,
}
}
// fileMode returns a Go os.FileMode from a Unix mode.
func fileMode(unixMode uint32) os.FileMode {
mode := os.FileMode(unixMode & 0777)
switch unixMode & syscall.S_IFMT {
case syscall.S_IFREG:
// nothing
case syscall.S_IFDIR:
mode |= os.ModeDir
case syscall.S_IFCHR:
mode |= os.ModeCharDevice | os.ModeDevice
case syscall.S_IFBLK:
mode |= os.ModeDevice
case syscall.S_IFIFO:
mode |= os.ModeNamedPipe
case syscall.S_IFLNK:
mode |= os.ModeSymlink
case syscall.S_IFSOCK:
mode |= os.ModeSocket
default:
// no idea
mode |= os.ModeDevice
}
if unixMode&syscall.S_ISUID != 0 {
mode |= os.ModeSetuid
}
if unixMode&syscall.S_ISGID != 0 {
mode |= os.ModeSetgid
}
return mode
}
type noOpcode struct {
Opcode uint32
}
func (m noOpcode) String() string {
return fmt.Sprintf("No opcode %v", m.Opcode)
}
type malformedMessage struct {
}
func (malformedMessage) String() string {
return "malformed message"
}
// Close closes the FUSE connection.
func (c *Conn) Close() error {
c.wio.Lock()
defer c.wio.Unlock()
c.rio.Lock()
defer c.rio.Unlock()
return c.dev.Close()
}
// caller must hold wio or rio
func (c *Conn) fd() int {
return int(c.dev.Fd())
}
func (c *Conn) Protocol() Protocol {
return c.proto
}
// ReadRequest returns the next FUSE request from the kernel.
//
// Caller must call either Request.Respond or Request.RespondError in
// a reasonable time. Caller must not retain Request after that call.
func (c *Conn) ReadRequest() (Request, error) {
m := getMessage(c)
loop:
c.rio.RLock()
n, err := syscall.Read(c.fd(), m.buf)
c.rio.RUnlock()
if err == syscall.EINTR {
// OSXFUSE sends EINTR to userspace when a request interrupt
// completed before it got sent to userspace?
goto loop
}
if err != nil && err != syscall.ENODEV {
putMessage(m)
return nil, err
}
if n <= 0 {
putMessage(m)
return nil, io.EOF
}
m.buf = m.buf[:n]
if n < inHeaderSize {
putMessage(m)
return nil, errors.New("fuse: message too short")
}
// FreeBSD FUSE sends a short length in the header
// for FUSE_INIT even though the actual read length is correct.
if n == inHeaderSize+initInSize && m.hdr.Opcode == opInit && m.hdr.Len < uint32(n) {
m.hdr.Len = uint32(n)
}
// OSXFUSE sometimes sends the wrong m.hdr.Len in a FUSE_WRITE message.
if m.hdr.Len < uint32(n) && m.hdr.Len >= uint32(unsafe.Sizeof(writeIn{})) && m.hdr.Opcode == opWrite {
m.hdr.Len = uint32(n)
}
if m.hdr.Len != uint32(n) {
// prepare error message before returning m to pool
err := fmt.Errorf("fuse: read %d opcode %d but expected %d", n, m.hdr.Opcode, m.hdr.Len)
putMessage(m)
return nil, err
}
m.off = inHeaderSize
// Convert to data structures.
// Do not trust kernel to hand us well-formed data.
var req Request
switch m.hdr.Opcode {
default:
Debug(noOpcode{Opcode: m.hdr.Opcode})
goto unrecognized
case opLookup:
buf := m.bytes()
n := len(buf)
if n == 0 || buf[n-1] != '\x00' {
goto corrupt
}
req = &LookupRequest{
Header: m.Header(),
Name: string(buf[:n-1]),
}
case opForget:
in := (*forgetIn)(m.data())
if m.len() < unsafe.Sizeof(*in) {
goto corrupt
}
req = &ForgetRequest{
Header: m.Header(),
N: in.Nlookup,
}
case opGetattr:
switch {
case c.proto.LT(Protocol{7, 9}):
req = &GetattrRequest{
Header: m.Header(),
}
default:
in := (*getattrIn)(m.data())
if m.len() < unsafe.Sizeof(*in) {
goto corrupt
}
req = &GetattrRequest{
Header: m.Header(),
Flags: GetattrFlags(in.GetattrFlags),
Handle: HandleID(in.Fh),
}
}
case opSetattr:
in := (*setattrIn)(m.data())
if m.len() < unsafe.Sizeof(*in) {
goto corrupt
}
req = &SetattrRequest{
Header: m.Header(),
Valid: SetattrValid(in.Valid),
Handle: HandleID(in.Fh),
Size: in.Size,
Atime: time.Unix(int64(in.Atime), int64(in.AtimeNsec)),
Mtime: time.Unix(int64(in.Mtime), int64(in.MtimeNsec)),
Mode: fileMode(in.Mode),
Uid: in.Uid,
Gid: in.Gid,
Bkuptime: in.BkupTime(),
Chgtime: in.Chgtime(),
Flags: in.Flags(),
}
case opReadlink:
if len(m.bytes()) > 0 {
goto corrupt
}
req = &ReadlinkRequest{
Header: m.Header(),
}
case opSymlink:
// m.bytes() is "newName\0target\0"
names := m.bytes()
if len(names) == 0 || names[len(names)-1] != 0 {
goto corrupt
}
i := bytes.IndexByte(names, '\x00')
if i < 0 {
goto corrupt
}
newName, target := names[0:i], names[i+1:len(names)-1]
req = &SymlinkRequest{
Header: m.Header(),
NewName: string(newName),
Target: string(target),
}
case opLink:
in := (*linkIn)(m.data())
if m.len() < unsafe.Sizeof(*in) {
goto corrupt
}
newName := m.bytes()[unsafe.Sizeof(*in):]
if len(newName) < 2 || newName[len(newName)-1] != 0 {
goto corrupt
}
newName = newName[:len(newName)-1]
req = &LinkRequest{
Header: m.Header(),
OldNode: NodeID(in.Oldnodeid),
NewName: string(newName),
}
case opMknod:
size := mknodInSize(c.proto)
if m.len() < size {
goto corrupt
}
in := (*mknodIn)(m.data())
name := m.bytes()[size:]
if len(name) < 2 || name[len(name)-1] != '\x00' {
goto corrupt
}
name = name[:len(name)-1]
r := &MknodRequest{
Header: m.Header(),
Mode: fileMode(in.Mode),
Rdev: in.Rdev,
Name: string(name),
}
if c.proto.GE(Protocol{7, 12}) {
r.Umask = fileMode(in.Umask) & os.ModePerm
}
req = r
case opMkdir:
size := mkdirInSize(c.proto)
if m.len() < size {
goto corrupt
}
in := (*mkdirIn)(m.data())
name := m.bytes()[size:]
i := bytes.IndexByte(name, '\x00')
if i < 0 {
goto corrupt
}
r := &MkdirRequest{
Header: m.Header(),
Name: string(name[:i]),
// observed on Linux: mkdirIn.Mode & syscall.S_IFMT == 0,
// and this causes fileMode to go into it's "no idea"
// code branch; enforce type to directory
Mode: fileMode((in.Mode &^ syscall.S_IFMT) | syscall.S_IFDIR),
}
if c.proto.GE(Protocol{7, 12}) {
r.Umask = fileMode(in.Umask) & os.ModePerm
}
req = r
case opUnlink, opRmdir:
buf := m.bytes()
n := len(buf)
if n == 0 || buf[n-1] != '\x00' {
goto corrupt
}
req = &RemoveRequest{
Header: m.Header(),
Name: string(buf[:n-1]),
Dir: m.hdr.Opcode == opRmdir,
}
case opRename:
in := (*renameIn)(m.data())
if m.len() < unsafe.Sizeof(*in) {
goto corrupt
}
newDirNodeID := NodeID(in.Newdir)
oldNew := m.bytes()[unsafe.Sizeof(*in):]
// oldNew should be "old\x00new\x00"
if len(oldNew) < 4 {
goto corrupt
}
if oldNew[len(oldNew)-1] != '\x00' {
goto corrupt
}
i := bytes.IndexByte(oldNew, '\x00')
if i < 0 {
goto corrupt
}
oldName, newName := string(oldNew[:i]), string(oldNew[i+1:len(oldNew)-1])
req = &RenameRequest{
Header: m.Header(),
NewDir: newDirNodeID,
OldName: oldName,
NewName: newName,
}
case opOpendir, opOpen:
in := (*openIn)(m.data())
if m.len() < unsafe.Sizeof(*in) {
goto corrupt
}
req = &OpenRequest{
Header: m.Header(),
Dir: m.hdr.Opcode == opOpendir,
Flags: openFlags(in.Flags),
}
case opRead, opReaddir:
in := (*readIn)(m.data())
if m.len() < readInSize(c.proto) {
goto corrupt
}
r := &ReadRequest{
Header: m.Header(),
Dir: m.hdr.Opcode == opReaddir,
Handle: HandleID(in.Fh),
Offset: int64(in.Offset),
Size: int(in.Size),
}
if c.proto.GE(Protocol{7, 9}) {
r.Flags = ReadFlags(in.ReadFlags)
r.LockOwner = in.LockOwner
r.FileFlags = openFlags(in.Flags)
}
req = r
case opWrite:
in := (*writeIn)(m.data())
if m.len() < writeInSize(c.proto) {
goto corrupt
}
r := &WriteRequest{
Header: m.Header(),
Handle: HandleID(in.Fh),
Offset: int64(in.Offset),
Flags: WriteFlags(in.WriteFlags),
}
if c.proto.GE(Protocol{7, 9}) {
r.LockOwner = in.LockOwner
r.FileFlags = openFlags(in.Flags)
}
buf := m.bytes()[writeInSize(c.proto):]
if uint32(len(buf)) < in.Size {
goto corrupt
}
r.Data = buf
req = r
case opStatfs:
req = &StatfsRequest{
Header: m.Header(),
}
case opRelease, opReleasedir:
in := (*releaseIn)(m.data())
if m.len() < unsafe.Sizeof(*in) {
goto corrupt
}
req = &ReleaseRequest{
Header: m.Header(),
Dir: m.hdr.Opcode == opReleasedir,
Handle: HandleID(in.Fh),
Flags: openFlags(in.Flags),
ReleaseFlags: ReleaseFlags(in.ReleaseFlags),
LockOwner: in.LockOwner,
}
case opFsync, opFsyncdir:
in := (*fsyncIn)(m.data())
if m.len() < unsafe.Sizeof(*in) {
goto corrupt
}
req = &FsyncRequest{
Dir: m.hdr.Opcode == opFsyncdir,
Header: m.Header(),
Handle: HandleID(in.Fh),
Flags: in.FsyncFlags,
}
case opSetxattr:
in := (*setxattrIn)(m.data())
if m.len() < unsafe.Sizeof(*in) {
goto corrupt
}
m.off += int(unsafe.Sizeof(*in))
name := m.bytes()
i := bytes.IndexByte(name, '\x00')
if i < 0 {
goto corrupt
}
xattr := name[i+1:]
if uint32(len(xattr)) < in.Size {
goto corrupt
}
xattr = xattr[:in.Size]
req = &SetxattrRequest{
Header: m.Header(),
Flags: in.Flags,
Position: in.position(),
Name: string(name[:i]),
Xattr: xattr,
}
case opGetxattr:
in := (*getxattrIn)(m.data())
if m.len() < unsafe.Sizeof(*in) {
goto corrupt
}
name := m.bytes()[unsafe.Sizeof(*in):]
i := bytes.IndexByte(name, '\x00')
if i < 0 {
goto corrupt
}
req = &GetxattrRequest{
Header: m.Header(),
Name: string(name[:i]),
Size: in.Size,
Position: in.position(),
}
case opListxattr:
in := (*getxattrIn)(m.data())
if m.len() < unsafe.Sizeof(*in) {
goto corrupt
}
req = &ListxattrRequest{
Header: m.Header(),
Size: in.Size,
Position: in.position(),
}
case opRemovexattr:
buf := m.bytes()
n := len(buf)
if n == 0 || buf[n-1] != '\x00' {
goto corrupt
}
req = &RemovexattrRequest{
Header: m.Header(),
Name: string(buf[:n-1]),
}
case opFlush:
in := (*flushIn)(m.data())
if m.len() < unsafe.Sizeof(*in) {
goto corrupt
}
req = &FlushRequest{
Header: m.Header(),
Handle: HandleID(in.Fh),
Flags: in.FlushFlags,
LockOwner: in.LockOwner,
}
case opInit:
in := (*initIn)(m.data())
if m.len() < unsafe.Sizeof(*in) {
goto corrupt
}
req = &InitRequest{
Header: m.Header(),
Kernel: Protocol{in.Major, in.Minor},
MaxReadahead: in.MaxReadahead,
Flags: InitFlags(in.Flags),
}
case opGetlk:
panic("opGetlk")
case opSetlk:
panic("opSetlk")
case opSetlkw:
panic("opSetlkw")
case opAccess:
in := (*accessIn)(m.data())
if m.len() < unsafe.Sizeof(*in) {
goto corrupt
}
req = &AccessRequest{
Header: m.Header(),
Mask: in.Mask,
}
case opCreate:
size := createInSize(c.proto)
if m.len() < size {
goto corrupt
}
in := (*createIn)(m.data())
name := m.bytes()[size:]
i := bytes.IndexByte(name, '\x00')
if i < 0 {
goto corrupt
}
r := &CreateRequest{
Header: m.Header(),
Flags: openFlags(in.Flags),
Mode: fileMode(in.Mode),
Name: string(name[:i]),
}
if c.proto.GE(Protocol{7, 12}) {
r.Umask = fileMode(in.Umask) & os.ModePerm
}
req = r
case opInterrupt:
in := (*interruptIn)(m.data())
if m.len() < unsafe.Sizeof(*in) {
goto corrupt
}
req = &InterruptRequest{
Header: m.Header(),
IntrID: RequestID(in.Unique),
}
case opBmap:
panic("opBmap")
case opDestroy:
req = &DestroyRequest{
Header: m.Header(),
}
// OS X
case opSetvolname:
panic("opSetvolname")
case opGetxtimes:
panic("opGetxtimes")
case opExchange:
in := (*exchangeIn)(m.data())
if m.len() < unsafe.Sizeof(*in) {
goto corrupt
}
oldDirNodeID := NodeID(in.Olddir)
newDirNodeID := NodeID(in.Newdir)
oldNew := m.bytes()[unsafe.Sizeof(*in):]
// oldNew should be "oldname\x00newname\x00"
if len(oldNew) < 4 {
goto corrupt
}
if oldNew[len(oldNew)-1] != '\x00' {
goto corrupt
}
i := bytes.IndexByte(oldNew, '\x00')
if i < 0 {
goto corrupt
}
oldName, newName := string(oldNew[:i]), string(oldNew[i+1:len(oldNew)-1])
req = &ExchangeDataRequest{
Header: m.Header(),
OldDir: oldDirNodeID,
NewDir: newDirNodeID,
OldName: oldName,
NewName: newName,
// TODO options
}
}
return req, nil
corrupt:
Debug(malformedMessage{})
putMessage(m)
return nil, fmt.Errorf("fuse: malformed message")
unrecognized:
// Unrecognized message.
// Assume higher-level code will send a "no idea what you mean" error.
h := m.Header()
return &h, nil
}
type bugShortKernelWrite struct {
Written int64
Length int64
Error string
Stack string
}
func (b bugShortKernelWrite) String() string {
return fmt.Sprintf("short kernel write: written=%d/%d error=%q stack=\n%s", b.Written, b.Length, b.Error, b.Stack)
}
type bugKernelWriteError struct {
Error string
Stack string
}
func (b bugKernelWriteError) String() string {
return fmt.Sprintf("kernel write error: error=%q stack=\n%s", b.Error, b.Stack)
}
// safe to call even with nil error
func errorString(err error) string {
if err == nil {
return ""
}
return err.Error()
}
func (c *Conn) writeToKernel(msg []byte) error {
out := (*outHeader)(unsafe.Pointer(&msg[0]))
out.Len = uint32(len(msg))
c.wio.RLock()
defer c.wio.RUnlock()
nn, err := syscall.Write(c.fd(), msg)
if err == nil && nn != len(msg) {
Debug(bugShortKernelWrite{
Written: int64(nn),
Length: int64(len(msg)),
Error: errorString(err),
Stack: stack(),
})
}
return err
}
func (c *Conn) respond(msg []byte) {
if err := c.writeToKernel(msg); err != nil {
Debug(bugKernelWriteError{
Error: errorString(err),
Stack: stack(),
})
}
}
type notCachedError struct{}
func (notCachedError) Error() string {
return "node not cached"
}
var _ ErrorNumber = notCachedError{}
func (notCachedError) Errno() Errno {
// Behave just like if the original syscall.ENOENT had been passed
// straight through.
return ENOENT
}
var (
ErrNotCached = notCachedError{}
)
// sendInvalidate sends an invalidate notification to kernel.
//
// A returned ENOENT is translated to a friendlier error.
func (c *Conn) sendInvalidate(msg []byte) error {
switch err := c.writeToKernel(msg); err {
case syscall.ENOENT:
return ErrNotCached
default:
return err
}
}
// InvalidateNode invalidates the kernel cache of the attributes and a
// range of the data of a node.
//
// Giving offset 0 and size -1 means all data. To invalidate just the
// attributes, give offset 0 and size 0.
//
// Returns ErrNotCached if the kernel is not currently caching the
// node.
func (c *Conn) InvalidateNode(nodeID NodeID, off int64, size int64) error {
buf := newBuffer(unsafe.Sizeof(notifyInvalInodeOut{}))
h := (*outHeader)(unsafe.Pointer(&buf[0]))
// h.Unique is 0
h.Error = notifyCodeInvalInode
out := (*notifyInvalInodeOut)(buf.alloc(unsafe.Sizeof(notifyInvalInodeOut{})))
out.Ino = uint64(nodeID)
out.Off = off
out.Len = size
return c.sendInvalidate(buf)
}
// InvalidateEntry invalidates the kernel cache of the directory entry
// identified by parent directory node ID and entry basename.
//
// Kernel may or may not cache directory listings. To invalidate
// those, use InvalidateNode to invalidate all of the data for a
// directory. (As of 2015-06, Linux FUSE does not cache directory
// listings.)
//
// Returns ErrNotCached if the kernel is not currently caching the
// node.
func (c *Conn) InvalidateEntry(parent NodeID, name string) error {
const maxUint32 = ^uint32(0)
if uint64(len(name)) > uint64(maxUint32) {
// very unlikely, but we don't want to silently truncate
return syscall.ENAMETOOLONG
}
buf := newBuffer(unsafe.Sizeof(notifyInvalEntryOut{}) + uintptr(len(name)) + 1)
h := (*outHeader)(unsafe.Pointer(&buf[0]))
// h.Unique is 0
h.Error = notifyCodeInvalEntry
out := (*notifyInvalEntryOut)(buf.alloc(unsafe.Sizeof(notifyInvalEntryOut{})))
out.Parent = uint64(parent)
out.Namelen = uint32(len(name))
buf = append(buf, name...)
buf = append(buf, '\x00')
return c.sendInvalidate(buf)
}
// An InitRequest is the first request sent on a FUSE file system.
type InitRequest struct {
Header `json:"-"`
Kernel Protocol
// Maximum readahead in bytes that the kernel plans to use.
MaxReadahead uint32
Flags InitFlags
}
var _ = Request(&InitRequest{})
func (r *InitRequest) String() string {
return fmt.Sprintf("Init [%v] %v ra=%d fl=%v", &r.Header, r.Kernel, r.MaxReadahead, r.Flags)
}
// An InitResponse is the response to an InitRequest.
type InitResponse struct {
Library Protocol
// Maximum readahead in bytes that the kernel can use. Ignored if
// greater than InitRequest.MaxReadahead.
MaxReadahead uint32
Flags InitFlags
// Maximum size of a single write operation.
// Linux enforces a minimum of 4 KiB.
MaxWrite uint32
}
func (r *InitResponse) String() string {
return fmt.Sprintf("Init %v ra=%d fl=%v w=%d", r.Library, r.MaxReadahead, r.Flags, r.MaxWrite)
}
// Respond replies to the request with the given response.
func (r *InitRequest) Respond(resp *InitResponse) {
buf := newBuffer(unsafe.Sizeof(initOut{}))
out := (*initOut)(buf.alloc(unsafe.Sizeof(initOut{})))
out.Major = resp.Library.Major
out.Minor = resp.Library.Minor
out.MaxReadahead = resp.MaxReadahead
out.Flags = uint32(resp.Flags)
out.MaxWrite = resp.MaxWrite
// MaxWrite larger than our receive buffer would just lead to
// errors on large writes.
if out.MaxWrite > maxWrite {
out.MaxWrite = maxWrite
}
r.respond(buf)
}
// A StatfsRequest requests information about the mounted file system.
type StatfsRequest struct {
Header `json:"-"`
}
var _ = Request(&StatfsRequest{})
func (r *StatfsRequest) String() string {
return fmt.Sprintf("Statfs [%s]", &r.Header)
}
// Respond replies to the request with the given response.
func (r *StatfsRequest) Respond(resp *StatfsResponse) {
buf := newBuffer(unsafe.Sizeof(statfsOut{}))
out := (*statfsOut)(buf.alloc(unsafe.Sizeof(statfsOut{})))
out.St = kstatfs{
Blocks: resp.Blocks,
Bfree: resp.Bfree,
Bavail: resp.Bavail,
Files: resp.Files,
Bsize: resp.Bsize,
Namelen: resp.Namelen,
Frsize: resp.Frsize,
}
r.respond(buf)
}
// A StatfsResponse is the response to a StatfsRequest.
type StatfsResponse struct {
Blocks uint64 // Total data blocks in file system.
Bfree uint64 // Free blocks in file system.
Bavail uint64 // Free blocks in file system if you're not root.
Files uint64 // Total files in file system.
Ffree uint64 // Free files in file system.
Bsize uint32 // Block size
Namelen uint32 // Maximum file name length?
Frsize uint32 // Fragment size, smallest addressable data size in the file system.
}
func (r *StatfsResponse) String() string {
return fmt.Sprintf("Statfs blocks=%d/%d/%d files=%d/%d bsize=%d frsize=%d namelen=%d",
r.Bavail, r.Bfree, r.Blocks,
r.Ffree, r.Files,
r.Bsize,
r.Frsize,
r.Namelen,
)
}
// An AccessRequest asks whether the file can be accessed
// for the purpose specified by the mask.
type AccessRequest struct {
Header `json:"-"`
Mask uint32
}
var _ = Request(&AccessRequest{})
func (r *AccessRequest) String() string {
return fmt.Sprintf("Access [%s] mask=%#x", &r.Header, r.Mask)
}
// Respond replies to the request indicating that access is allowed.
// To deny access, use RespondError.
func (r *AccessRequest) Respond() {
buf := newBuffer(0)
r.respond(buf)
}
// An Attr is the metadata for a single file or directory.
type Attr struct {
Valid time.Duration // how long Attr can be cached
Inode uint64 // inode number
Size uint64 // size in bytes
Blocks uint64 // size in 512-byte units
Atime time.Time // time of last access
Mtime time.Time // time of last modification
Ctime time.Time // time of last inode change
Crtime time.Time // time of creation (OS X only)
Mode os.FileMode // file mode
Nlink uint32 // number of links (usually 1)
Uid uint32 // owner uid
Gid uint32 // group gid
Rdev uint32 // device numbers
Flags uint32 // chflags(2) flags (OS X only)
BlockSize uint32 // preferred blocksize for filesystem I/O
}
func (a Attr) String() string {
return fmt.Sprintf("valid=%v ino=%v size=%d mode=%v", a.Valid, a.Inode, a.Size, a.Mode)
}
func unix(t time.Time) (sec uint64, nsec uint32) {
nano := t.UnixNano()
sec = uint64(nano / 1e9)
nsec = uint32(nano % 1e9)
return
}
func (a *Attr) attr(out *attr, proto Protocol) {
out.Ino = a.Inode
out.Size = a.Size
out.Blocks = a.Blocks
out.Atime, out.AtimeNsec = unix(a.Atime)
out.Mtime, out.MtimeNsec = unix(a.Mtime)
out.Ctime, out.CtimeNsec = unix(a.Ctime)
out.SetCrtime(unix(a.Crtime))
out.Mode = uint32(a.Mode) & 0777
switch {
default:
out.Mode |= syscall.S_IFREG
case a.Mode&os.ModeDir != 0:
out.Mode |= syscall.S_IFDIR
case a.Mode&os.ModeDevice != 0:
if a.Mode&os.ModeCharDevice != 0 {
out.Mode |= syscall.S_IFCHR
} else {
out.Mode |= syscall.S_IFBLK
}
case a.Mode&os.ModeNamedPipe != 0:
out.Mode |= syscall.S_IFIFO
case a.Mode&os.ModeSymlink != 0:
out.Mode |= syscall.S_IFLNK
case a.Mode&os.ModeSocket != 0:
out.Mode |= syscall.S_IFSOCK
}
if a.Mode&os.ModeSetuid != 0 {
out.Mode |= syscall.S_ISUID
}
if a.Mode&os.ModeSetgid != 0 {
out.Mode |= syscall.S_ISGID
}
out.Nlink = a.Nlink
out.Uid = a.Uid
out.Gid = a.Gid
out.Rdev = a.Rdev
out.SetFlags(a.Flags)
if proto.GE(Protocol{7, 9}) {
out.Blksize = a.BlockSize
}
return
}
// A GetattrRequest asks for the metadata for the file denoted by r.Node.
type GetattrRequest struct {
Header `json:"-"`
Flags GetattrFlags
Handle HandleID
}
var _ = Request(&GetattrRequest{})
func (r *GetattrRequest) String() string {
return fmt.Sprintf("Getattr [%s] %v fl=%v", &r.Header, r.Handle, r.Flags)
}
// Respond replies to the request with the given response.
func (r *GetattrRequest) Respond(resp *GetattrResponse) {
size := attrOutSize(r.Header.Conn.proto)
buf := newBuffer(size)
out := (*attrOut)(buf.alloc(size))
out.AttrValid = uint64(resp.Attr.Valid / time.Second)
out.AttrValidNsec = uint32(resp.Attr.Valid % time.Second / time.Nanosecond)
resp.Attr.attr(&out.Attr, r.Header.Conn.proto)
r.respond(buf)
}
// A GetattrResponse is the response to a GetattrRequest.
type GetattrResponse struct {
Attr Attr // file attributes
}
func (r *GetattrResponse) String() string {
return fmt.Sprintf("Getattr %v", r.Attr)
}
// A GetxattrRequest asks for the extended attributes associated with r.Node.
type GetxattrRequest struct {
Header `json:"-"`
// Maximum size to return.
Size uint32
// Name of the attribute requested.
Name string
// Offset within extended attributes.
//
// Only valid for OS X, and then only with the resource fork
// attribute.
Position uint32
}
var _ = Request(&GetxattrRequest{})
func (r *GetxattrRequest) String() string {
return fmt.Sprintf("Getxattr [%s] %q %d @%d", &r.Header, r.Name, r.Size, r.Position)
}
// Respond replies to the request with the given response.
func (r *GetxattrRequest) Respond(resp *GetxattrResponse) {
if r.Size == 0 {
buf := newBuffer(unsafe.Sizeof(getxattrOut{}))
out := (*getxattrOut)(buf.alloc(unsafe.Sizeof(getxattrOut{})))
out.Size = uint32(len(resp.Xattr))
r.respond(buf)
} else {
buf := newBuffer(uintptr(len(resp.Xattr)))
buf = append(buf, resp.Xattr...)
r.respond(buf)
}
}
// A GetxattrResponse is the response to a GetxattrRequest.
type GetxattrResponse struct {
Xattr []byte
}
func (r *GetxattrResponse) String() string {
return fmt.Sprintf("Getxattr %x", r.Xattr)
}
// A ListxattrRequest asks to list the extended attributes associated with r.Node.
type ListxattrRequest struct {
Header `json:"-"`
Size uint32 // maximum size to return
Position uint32 // offset within attribute list
}
var _ = Request(&ListxattrRequest{})
func (r *ListxattrRequest) String() string {
return fmt.Sprintf("Listxattr [%s] %d @%d", &r.Header, r.Size, r.Position)
}
// Respond replies to the request with the given response.
func (r *ListxattrRequest) Respond(resp *ListxattrResponse) {
if r.Size == 0 {
buf := newBuffer(unsafe.Sizeof(getxattrOut{}))
out := (*getxattrOut)(buf.alloc(unsafe.Sizeof(getxattrOut{})))
out.Size = uint32(len(resp.Xattr))
r.respond(buf)
} else {
buf := newBuffer(uintptr(len(resp.Xattr)))
buf = append(buf, resp.Xattr...)
r.respond(buf)
}
}
// A ListxattrResponse is the response to a ListxattrRequest.
type ListxattrResponse struct {
Xattr []byte
}
func (r *ListxattrResponse) String() string {
return fmt.Sprintf("Listxattr %x", r.Xattr)
}
// Append adds an extended attribute name to the response.
func (r *ListxattrResponse) Append(names ...string) {
for _, name := range names {
r.Xattr = append(r.Xattr, name...)
r.Xattr = append(r.Xattr, '\x00')
}
}
// A RemovexattrRequest asks to remove an extended attribute associated with r.Node.
type RemovexattrRequest struct {
Header `json:"-"`
Name string // name of extended attribute
}
var _ = Request(&RemovexattrRequest{})
func (r *RemovexattrRequest) String() string {
return fmt.Sprintf("Removexattr [%s] %q", &r.Header, r.Name)
}
// Respond replies to the request, indicating that the attribute was removed.
func (r *RemovexattrRequest) Respond() {
buf := newBuffer(0)
r.respond(buf)
}
// A SetxattrRequest asks to set an extended attribute associated with a file.
type SetxattrRequest struct {
Header `json:"-"`
// Flags can make the request fail if attribute does/not already
// exist. Unfortunately, the constants are platform-specific and
// not exposed by Go1.2. Look for XATTR_CREATE, XATTR_REPLACE.
//
// TODO improve this later
//
// TODO XATTR_CREATE and exist -> EEXIST
//
// TODO XATTR_REPLACE and not exist -> ENODATA
Flags uint32
// Offset within extended attributes.
//
// Only valid for OS X, and then only with the resource fork
// attribute.
Position uint32
Name string
Xattr []byte
}
var _ = Request(&SetxattrRequest{})
func trunc(b []byte, max int) ([]byte, string) {
if len(b) > max {
return b[:max], "..."
}
return b, ""
}
func (r *SetxattrRequest) String() string {
xattr, tail := trunc(r.Xattr, 16)
return fmt.Sprintf("Setxattr [%s] %q %x%s fl=%v @%#x", &r.Header, r.Name, xattr, tail, r.Flags, r.Position)
}
// Respond replies to the request, indicating that the extended attribute was set.
func (r *SetxattrRequest) Respond() {
buf := newBuffer(0)
r.respond(buf)
}
// A LookupRequest asks to look up the given name in the directory named by r.Node.
type LookupRequest struct {
Header `json:"-"`
Name string
}
var _ = Request(&LookupRequest{})
func (r *LookupRequest) String() string {
return fmt.Sprintf("Lookup [%s] %q", &r.Header, r.Name)
}
// Respond replies to the request with the given response.
func (r *LookupRequest) Respond(resp *LookupResponse) {
size := entryOutSize(r.Header.Conn.proto)
buf := newBuffer(size)
out := (*entryOut)(buf.alloc(size))
out.Nodeid = uint64(resp.Node)
out.Generation = resp.Generation
out.EntryValid = uint64(resp.EntryValid / time.Second)
out.EntryValidNsec = uint32(resp.EntryValid % time.Second / time.Nanosecond)
out.AttrValid = uint64(resp.Attr.Valid / time.Second)
out.AttrValidNsec = uint32(resp.Attr.Valid % time.Second / time.Nanosecond)
resp.Attr.attr(&out.Attr, r.Header.Conn.proto)
r.respond(buf)
}
// A LookupResponse is the response to a LookupRequest.
type LookupResponse struct {
Node NodeID
Generation uint64
EntryValid time.Duration
Attr Attr
}
func (r *LookupResponse) string() string {
return fmt.Sprintf("%v gen=%d valid=%v attr={%v}", r.Node, r.Generation, r.EntryValid, r.Attr)
}
func (r *LookupResponse) String() string {
return fmt.Sprintf("Lookup %s", r.string())
}
// An OpenRequest asks to open a file or directory
type OpenRequest struct {
Header `json:"-"`
Dir bool // is this Opendir?
Flags OpenFlags
}
var _ = Request(&OpenRequest{})
func (r *OpenRequest) String() string {
return fmt.Sprintf("Open [%s] dir=%v fl=%v", &r.Header, r.Dir, r.Flags)
}
// Respond replies to the request with the given response.
func (r *OpenRequest) Respond(resp *OpenResponse) {
buf := newBuffer(unsafe.Sizeof(openOut{}))
out := (*openOut)(buf.alloc(unsafe.Sizeof(openOut{})))
out.Fh = uint64(resp.Handle)
out.OpenFlags = uint32(resp.Flags)
r.respond(buf)
}
// A OpenResponse is the response to a OpenRequest.
type OpenResponse struct {
Handle HandleID
Flags OpenResponseFlags
}
func (r *OpenResponse) string() string {
return fmt.Sprintf("%v fl=%v", r.Handle, r.Flags)
}
func (r *OpenResponse) String() string {
return fmt.Sprintf("Open %s", r.string())
}
// A CreateRequest asks to create and open a file (not a directory).
type CreateRequest struct {
Header `json:"-"`
Name string
Flags OpenFlags
Mode os.FileMode
// Umask of the request. Not supported on OS X.
Umask os.FileMode
}
var _ = Request(&CreateRequest{})
func (r *CreateRequest) String() string {
return fmt.Sprintf("Create [%s] %q fl=%v mode=%v umask=%v", &r.Header, r.Name, r.Flags, r.Mode, r.Umask)
}
// Respond replies to the request with the given response.
func (r *CreateRequest) Respond(resp *CreateResponse) {
eSize := entryOutSize(r.Header.Conn.proto)
buf := newBuffer(eSize + unsafe.Sizeof(openOut{}))
e := (*entryOut)(buf.alloc(eSize))
e.Nodeid = uint64(resp.Node)
e.Generation = resp.Generation
e.EntryValid = uint64(resp.EntryValid / time.Second)
e.EntryValidNsec = uint32(resp.EntryValid % time.Second / time.Nanosecond)
e.AttrValid = uint64(resp.Attr.Valid / time.Second)
e.AttrValidNsec = uint32(resp.Attr.Valid % time.Second / time.Nanosecond)
resp.Attr.attr(&e.Attr, r.Header.Conn.proto)
o := (*openOut)(buf.alloc(unsafe.Sizeof(openOut{})))
o.Fh = uint64(resp.Handle)
o.OpenFlags = uint32(resp.Flags)
r.respond(buf)
}
// A CreateResponse is the response to a CreateRequest.
// It describes the created node and opened handle.
type CreateResponse struct {
LookupResponse
OpenResponse
}
func (r *CreateResponse) String() string {
return fmt.Sprintf("Create {%s} {%s}", r.LookupResponse.string(), r.OpenResponse.string())
}
// A MkdirRequest asks to create (but not open) a directory.
type MkdirRequest struct {
Header `json:"-"`
Name string
Mode os.FileMode
// Umask of the request. Not supported on OS X.
Umask os.FileMode
}
var _ = Request(&MkdirRequest{})
func (r *MkdirRequest) String() string {
return fmt.Sprintf("Mkdir [%s] %q mode=%v umask=%v", &r.Header, r.Name, r.Mode, r.Umask)
}
// Respond replies to the request with the given response.
func (r *MkdirRequest) Respond(resp *MkdirResponse) {
size := entryOutSize(r.Header.Conn.proto)
buf := newBuffer(size)
out := (*entryOut)(buf.alloc(size))
out.Nodeid = uint64(resp.Node)
out.Generation = resp.Generation
out.EntryValid = uint64(resp.EntryValid / time.Second)
out.EntryValidNsec = uint32(resp.EntryValid % time.Second / time.Nanosecond)
out.AttrValid = uint64(resp.Attr.Valid / time.Second)
out.AttrValidNsec = uint32(resp.Attr.Valid % time.Second / time.Nanosecond)
resp.Attr.attr(&out.Attr, r.Header.Conn.proto)
r.respond(buf)
}
// A MkdirResponse is the response to a MkdirRequest.
type MkdirResponse struct {
LookupResponse
}
func (r *MkdirResponse) String() string {
return fmt.Sprintf("Mkdir %v", r.LookupResponse.string())
}
// A ReadRequest asks to read from an open file.
type ReadRequest struct {
Header `json:"-"`
Dir bool // is this Readdir?
Handle HandleID
Offset int64
Size int
Flags ReadFlags
LockOwner uint64
FileFlags OpenFlags
}
var _ = Request(&ReadRequest{})
func (r *ReadRequest) String() string {
return fmt.Sprintf("Read [%s] %v %d @%#x dir=%v fl=%v lock=%d ffl=%v", &r.Header, r.Handle, r.Size, r.Offset, r.Dir, r.Flags, r.LockOwner, r.FileFlags)
}
// Respond replies to the request with the given response.
func (r *ReadRequest) Respond(resp *ReadResponse) {
buf := newBuffer(uintptr(len(resp.Data)))
buf = append(buf, resp.Data...)
r.respond(buf)
}
// A ReadResponse is the response to a ReadRequest.
type ReadResponse struct {
Data []byte
}
func (r *ReadResponse) String() string {
return fmt.Sprintf("Read %d", len(r.Data))
}
type jsonReadResponse struct {
Len uint64
}
func (r *ReadResponse) MarshalJSON() ([]byte, error) {
j := jsonReadResponse{
Len: uint64(len(r.Data)),
}
return json.Marshal(j)
}
// A ReleaseRequest asks to release (close) an open file handle.
type ReleaseRequest struct {
Header `json:"-"`
Dir bool // is this Releasedir?
Handle HandleID
Flags OpenFlags // flags from OpenRequest
ReleaseFlags ReleaseFlags
LockOwner uint32
}
var _ = Request(&ReleaseRequest{})
func (r *ReleaseRequest) String() string {
return fmt.Sprintf("Release [%s] %v fl=%v rfl=%v owner=%#x", &r.Header, r.Handle, r.Flags, r.ReleaseFlags, r.LockOwner)
}
// Respond replies to the request, indicating that the handle has been released.
func (r *ReleaseRequest) Respond() {
buf := newBuffer(0)
r.respond(buf)
}
// A DestroyRequest is sent by the kernel when unmounting the file system.
// No more requests will be received after this one, but it should still be
// responded to.
type DestroyRequest struct {
Header `json:"-"`
}
var _ = Request(&DestroyRequest{})
func (r *DestroyRequest) String() string {
return fmt.Sprintf("Destroy [%s]", &r.Header)
}
// Respond replies to the request.
func (r *DestroyRequest) Respond() {
buf := newBuffer(0)
r.respond(buf)
}
// A ForgetRequest is sent by the kernel when forgetting about r.Node
// as returned by r.N lookup requests.
type ForgetRequest struct {
Header `json:"-"`
N uint64
}
var _ = Request(&ForgetRequest{})
func (r *ForgetRequest) String() string {
return fmt.Sprintf("Forget [%s] %d", &r.Header, r.N)
}
// Respond replies to the request, indicating that the forgetfulness has been recorded.
func (r *ForgetRequest) Respond() {
// Don't reply to forget messages.
r.noResponse()
}
// A Dirent represents a single directory entry.
type Dirent struct {
// Inode this entry names.
Inode uint64
// Type of the entry, for example DT_File.
//
// Setting this is optional. The zero value (DT_Unknown) means
// callers will just need to do a Getattr when the type is
// needed. Providing a type can speed up operations
// significantly.
Type DirentType
// Name of the entry
Name string
}
// Type of an entry in a directory listing.
type DirentType uint32
const (
// These don't quite match os.FileMode; especially there's an
// explicit unknown, instead of zero value meaning file. They
// are also not quite syscall.DT_*; nothing says the FUSE
// protocol follows those, and even if they were, we don't
// want each fs to fiddle with syscall.
// The shift by 12 is hardcoded in the FUSE userspace
// low-level C library, so it's safe here.
DT_Unknown DirentType = 0
DT_Socket DirentType = syscall.S_IFSOCK >> 12
DT_Link DirentType = syscall.S_IFLNK >> 12
DT_File DirentType = syscall.S_IFREG >> 12
DT_Block DirentType = syscall.S_IFBLK >> 12
DT_Dir DirentType = syscall.S_IFDIR >> 12
DT_Char DirentType = syscall.S_IFCHR >> 12
DT_FIFO DirentType = syscall.S_IFIFO >> 12
)
func (t DirentType) String() string {
switch t {
case DT_Unknown:
return "unknown"
case DT_Socket:
return "socket"
case DT_Link:
return "link"
case DT_File:
return "file"
case DT_Block:
return "block"
case DT_Dir:
return "dir"
case DT_Char:
return "char"
case DT_FIFO:
return "fifo"
}
return "invalid"
}
// AppendDirent appends the encoded form of a directory entry to data
// and returns the resulting slice.
func AppendDirent(data []byte, dir Dirent) []byte {
de := dirent{
Ino: dir.Inode,
Namelen: uint32(len(dir.Name)),
Type: uint32(dir.Type),
}
de.Off = uint64(len(data) + direntSize + (len(dir.Name)+7)&^7)
data = append(data, (*[direntSize]byte)(unsafe.Pointer(&de))[:]...)
data = append(data, dir.Name...)
n := direntSize + uintptr(len(dir.Name))
if n%8 != 0 {
var pad [8]byte
data = append(data, pad[:8-n%8]...)
}
return data
}
// A WriteRequest asks to write to an open file.
type WriteRequest struct {
Header
Handle HandleID
Offset int64
Data []byte
Flags WriteFlags
LockOwner uint64
FileFlags OpenFlags
}
var _ = Request(&WriteRequest{})
func (r *WriteRequest) String() string {
return fmt.Sprintf("Write [%s] %v %d @%d fl=%v lock=%d ffl=%v", &r.Header, r.Handle, len(r.Data), r.Offset, r.Flags, r.LockOwner, r.FileFlags)
}
type jsonWriteRequest struct {
Handle HandleID
Offset int64
Len uint64
Flags WriteFlags
}
func (r *WriteRequest) MarshalJSON() ([]byte, error) {
j := jsonWriteRequest{
Handle: r.Handle,
Offset: r.Offset,
Len: uint64(len(r.Data)),
Flags: r.Flags,
}
return json.Marshal(j)
}
// Respond replies to the request with the given response.
func (r *WriteRequest) Respond(resp *WriteResponse) {
buf := newBuffer(unsafe.Sizeof(writeOut{}))
out := (*writeOut)(buf.alloc(unsafe.Sizeof(writeOut{})))
out.Size = uint32(resp.Size)
r.respond(buf)
}
// A WriteResponse replies to a write indicating how many bytes were written.
type WriteResponse struct {
Size int
}
func (r *WriteResponse) String() string {
return fmt.Sprintf("Write %d", r.Size)
}
// A SetattrRequest asks to change one or more attributes associated with a file,
// as indicated by Valid.
type SetattrRequest struct {
Header `json:"-"`
Valid SetattrValid
Handle HandleID
Size uint64
Atime time.Time
Mtime time.Time
Mode os.FileMode
Uid uint32
Gid uint32
// OS X only
Bkuptime time.Time
Chgtime time.Time
Crtime time.Time
Flags uint32 // see chflags(2)
}
var _ = Request(&SetattrRequest{})
func (r *SetattrRequest) String() string {
var buf bytes.Buffer
fmt.Fprintf(&buf, "Setattr [%s]", &r.Header)
if r.Valid.Mode() {
fmt.Fprintf(&buf, " mode=%v", r.Mode)
}
if r.Valid.Uid() {
fmt.Fprintf(&buf, " uid=%d", r.Uid)
}
if r.Valid.Gid() {
fmt.Fprintf(&buf, " gid=%d", r.Gid)
}
if r.Valid.Size() {
fmt.Fprintf(&buf, " size=%d", r.Size)
}
if r.Valid.Atime() {
fmt.Fprintf(&buf, " atime=%v", r.Atime)
}
if r.Valid.AtimeNow() {
fmt.Fprintf(&buf, " atime=now")
}
if r.Valid.Mtime() {
fmt.Fprintf(&buf, " mtime=%v", r.Mtime)
}
if r.Valid.MtimeNow() {
fmt.Fprintf(&buf, " mtime=now")
}
if r.Valid.Handle() {
fmt.Fprintf(&buf, " handle=%v", r.Handle)
} else {
fmt.Fprintf(&buf, " handle=INVALID-%v", r.Handle)
}
if r.Valid.LockOwner() {
fmt.Fprintf(&buf, " lockowner")
}
if r.Valid.Crtime() {
fmt.Fprintf(&buf, " crtime=%v", r.Crtime)
}
if r.Valid.Chgtime() {
fmt.Fprintf(&buf, " chgtime=%v", r.Chgtime)
}
if r.Valid.Bkuptime() {
fmt.Fprintf(&buf, " bkuptime=%v", r.Bkuptime)
}
if r.Valid.Flags() {
fmt.Fprintf(&buf, " flags=%v", r.Flags)
}
return buf.String()
}
// Respond replies to the request with the given response,
// giving the updated attributes.
func (r *SetattrRequest) Respond(resp *SetattrResponse) {
size := attrOutSize(r.Header.Conn.proto)
buf := newBuffer(size)
out := (*attrOut)(buf.alloc(size))
out.AttrValid = uint64(resp.Attr.Valid / time.Second)
out.AttrValidNsec = uint32(resp.Attr.Valid % time.Second / time.Nanosecond)
resp.Attr.attr(&out.Attr, r.Header.Conn.proto)
r.respond(buf)
}
// A SetattrResponse is the response to a SetattrRequest.
type SetattrResponse struct {
Attr Attr // file attributes
}
func (r *SetattrResponse) String() string {
return fmt.Sprintf("Setattr %v", r.Attr)
}
// A FlushRequest asks for the current state of an open file to be flushed
// to storage, as when a file descriptor is being closed. A single opened Handle
// may receive multiple FlushRequests over its lifetime.
type FlushRequest struct {
Header `json:"-"`
Handle HandleID
Flags uint32
LockOwner uint64
}
var _ = Request(&FlushRequest{})
func (r *FlushRequest) String() string {
return fmt.Sprintf("Flush [%s] %v fl=%#x lk=%#x", &r.Header, r.Handle, r.Flags, r.LockOwner)
}
// Respond replies to the request, indicating that the flush succeeded.
func (r *FlushRequest) Respond() {
buf := newBuffer(0)
r.respond(buf)
}
// A RemoveRequest asks to remove a file or directory from the
// directory r.Node.
type RemoveRequest struct {
Header `json:"-"`
Name string // name of the entry to remove
Dir bool // is this rmdir?
}
var _ = Request(&RemoveRequest{})
func (r *RemoveRequest) String() string {
return fmt.Sprintf("Remove [%s] %q dir=%v", &r.Header, r.Name, r.Dir)
}
// Respond replies to the request, indicating that the file was removed.
func (r *RemoveRequest) Respond() {
buf := newBuffer(0)
r.respond(buf)
}
// A SymlinkRequest is a request to create a symlink making NewName point to Target.
type SymlinkRequest struct {
Header `json:"-"`
NewName, Target string
}
var _ = Request(&SymlinkRequest{})
func (r *SymlinkRequest) String() string {
return fmt.Sprintf("Symlink [%s] from %q to target %q", &r.Header, r.NewName, r.Target)
}
// Respond replies to the request, indicating that the symlink was created.
func (r *SymlinkRequest) Respond(resp *SymlinkResponse) {
size := entryOutSize(r.Header.Conn.proto)
buf := newBuffer(size)
out := (*entryOut)(buf.alloc(size))
out.Nodeid = uint64(resp.Node)
out.Generation = resp.Generation
out.EntryValid = uint64(resp.EntryValid / time.Second)
out.EntryValidNsec = uint32(resp.EntryValid % time.Second / time.Nanosecond)
out.AttrValid = uint64(resp.Attr.Valid / time.Second)
out.AttrValidNsec = uint32(resp.Attr.Valid % time.Second / time.Nanosecond)
resp.Attr.attr(&out.Attr, r.Header.Conn.proto)
r.respond(buf)
}
// A SymlinkResponse is the response to a SymlinkRequest.
type SymlinkResponse struct {
LookupResponse
}
func (r *SymlinkResponse) String() string {
return fmt.Sprintf("Symlink %v", r.LookupResponse.string())
}
// A ReadlinkRequest is a request to read a symlink's target.
type ReadlinkRequest struct {
Header `json:"-"`
}
var _ = Request(&ReadlinkRequest{})
func (r *ReadlinkRequest) String() string {
return fmt.Sprintf("Readlink [%s]", &r.Header)
}
func (r *ReadlinkRequest) Respond(target string) {
buf := newBuffer(uintptr(len(target)))
buf = append(buf, target...)
r.respond(buf)
}
// A LinkRequest is a request to create a hard link.
type LinkRequest struct {
Header `json:"-"`
OldNode NodeID
NewName string
}
var _ = Request(&LinkRequest{})
func (r *LinkRequest) String() string {
return fmt.Sprintf("Link [%s] node %d to %q", &r.Header, r.OldNode, r.NewName)
}
func (r *LinkRequest) Respond(resp *LookupResponse) {
size := entryOutSize(r.Header.Conn.proto)
buf := newBuffer(size)
out := (*entryOut)(buf.alloc(size))
out.Nodeid = uint64(resp.Node)
out.Generation = resp.Generation
out.EntryValid = uint64(resp.EntryValid / time.Second)
out.EntryValidNsec = uint32(resp.EntryValid % time.Second / time.Nanosecond)
out.AttrValid = uint64(resp.Attr.Valid / time.Second)
out.AttrValidNsec = uint32(resp.Attr.Valid % time.Second / time.Nanosecond)
resp.Attr.attr(&out.Attr, r.Header.Conn.proto)
r.respond(buf)
}
// A RenameRequest is a request to rename a file.
type RenameRequest struct {
Header `json:"-"`
NewDir NodeID
OldName, NewName string
}
var _ = Request(&RenameRequest{})
func (r *RenameRequest) String() string {
return fmt.Sprintf("Rename [%s] from %q to dirnode %v %q", &r.Header, r.OldName, r.NewDir, r.NewName)
}
func (r *RenameRequest) Respond() {
buf := newBuffer(0)
r.respond(buf)
}
type MknodRequest struct {
Header `json:"-"`
Name string
Mode os.FileMode
Rdev uint32
// Umask of the request. Not supported on OS X.
Umask os.FileMode
}
var _ = Request(&MknodRequest{})
func (r *MknodRequest) String() string {
return fmt.Sprintf("Mknod [%s] Name %q mode=%v umask=%v rdev=%d", &r.Header, r.Name, r.Mode, r.Umask, r.Rdev)
}
func (r *MknodRequest) Respond(resp *LookupResponse) {
size := entryOutSize(r.Header.Conn.proto)
buf := newBuffer(size)
out := (*entryOut)(buf.alloc(size))
out.Nodeid = uint64(resp.Node)
out.Generation = resp.Generation
out.EntryValid = uint64(resp.EntryValid / time.Second)
out.EntryValidNsec = uint32(resp.EntryValid % time.Second / time.Nanosecond)
out.AttrValid = uint64(resp.Attr.Valid / time.Second)
out.AttrValidNsec = uint32(resp.Attr.Valid % time.Second / time.Nanosecond)
resp.Attr.attr(&out.Attr, r.Header.Conn.proto)
r.respond(buf)
}
type FsyncRequest struct {
Header `json:"-"`
Handle HandleID
// TODO bit 1 is datasync, not well documented upstream
Flags uint32
Dir bool
}
var _ = Request(&FsyncRequest{})
func (r *FsyncRequest) String() string {
return fmt.Sprintf("Fsync [%s] Handle %v Flags %v", &r.Header, r.Handle, r.Flags)
}
func (r *FsyncRequest) Respond() {
buf := newBuffer(0)
r.respond(buf)
}
// An InterruptRequest is a request to interrupt another pending request. The
// response to that request should return an error status of EINTR.
type InterruptRequest struct {
Header `json:"-"`
IntrID RequestID // ID of the request to be interrupt.
}
var _ = Request(&InterruptRequest{})
func (r *InterruptRequest) Respond() {
// nothing to do here
r.noResponse()
}
func (r *InterruptRequest) String() string {
return fmt.Sprintf("Interrupt [%s] ID %v", &r.Header, r.IntrID)
}
// An ExchangeDataRequest is a request to exchange the contents of two
// files, while leaving most metadata untouched.
//
// This request comes from OS X exchangedata(2) and represents its
// specific semantics. Crucially, it is very different from Linux
// renameat(2) RENAME_EXCHANGE.
//
// https://developer.apple.com/library/mac/documentation/Darwin/Reference/ManPages/man2/exchangedata.2.html
type ExchangeDataRequest struct {
Header `json:"-"`
OldDir, NewDir NodeID
OldName, NewName string
// TODO options
}
var _ = Request(&ExchangeDataRequest{})
func (r *ExchangeDataRequest) String() string {
// TODO options
return fmt.Sprintf("ExchangeData [%s] %v %q and %v %q", &r.Header, r.OldDir, r.OldName, r.NewDir, r.NewName)
}
func (r *ExchangeDataRequest) Respond() {
buf := newBuffer(0)
r.respond(buf)
}
<?xml version="1.0" encoding="UTF-8"?>
<module type="GO_MODULE" version="4">
<component name="NewModuleRootManager" inherit-compiler-output="true">
<exclude-output />
<content url="file://$MODULE_DIR$" />
<orderEntry type="inheritedJdk" />
<orderEntry type="sourceFolder" forTests="false" />
</component>
</module>
\ No newline at end of file
package fuse
// Maximum file write size we are prepared to receive from the kernel.
//
// This value has to be >=16MB or OSXFUSE (3.4.0 observed) will
// forcibly close the /dev/fuse file descriptor on a Setxattr with a
// 16MB value. See TestSetxattr16MB and
// https://github.com/bazil/fuse/issues/42
const maxWrite = 16 * 1024 * 1024
package fuse
// Maximum file write size we are prepared to receive from the kernel.
//
// This number is just a guess.
const maxWrite = 128 * 1024
// See the file LICENSE for copyright and licensing information.
// Derived from FUSE's fuse_kernel.h, which carries this notice:
/*
This file defines the kernel interface of FUSE
Copyright (C) 2001-2007 Miklos Szeredi <miklos@szeredi.hu>
This -- and only this -- header file may also be distributed under
the terms of the BSD Licence as follows:
Copyright (C) 2001-2007 Miklos Szeredi. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.
*/
package fuse
import (
"fmt"
"syscall"
"unsafe"
)
// The FUSE version implemented by the package.
const (
protoVersionMinMajor = 7
protoVersionMinMinor = 8
protoVersionMaxMajor = 7
protoVersionMaxMinor = 12
)
const (
rootID = 1
)
type kstatfs struct {
Blocks uint64
Bfree uint64
Bavail uint64
Files uint64
Ffree uint64
Bsize uint32
Namelen uint32
Frsize uint32
_ uint32
Spare [6]uint32
}
type fileLock struct {
Start uint64
End uint64
Type uint32
Pid uint32
}
// GetattrFlags are bit flags that can be seen in GetattrRequest.
type GetattrFlags uint32
const (
// Indicates the handle is valid.
GetattrFh GetattrFlags = 1 << 0
)
var getattrFlagsNames = []flagName{
{uint32(GetattrFh), "GetattrFh"},
}
func (fl GetattrFlags) String() string {
return flagString(uint32(fl), getattrFlagsNames)
}
// The SetattrValid are bit flags describing which fields in the SetattrRequest
// are included in the change.
type SetattrValid uint32
const (
SetattrMode SetattrValid = 1 << 0
SetattrUid SetattrValid = 1 << 1
SetattrGid SetattrValid = 1 << 2
SetattrSize SetattrValid = 1 << 3
SetattrAtime SetattrValid = 1 << 4
SetattrMtime SetattrValid = 1 << 5
SetattrHandle SetattrValid = 1 << 6
// Linux only(?)
SetattrAtimeNow SetattrValid = 1 << 7
SetattrMtimeNow SetattrValid = 1 << 8
SetattrLockOwner SetattrValid = 1 << 9 // http://www.mail-archive.com/git-commits-head@vger.kernel.org/msg27852.html
// OS X only
SetattrCrtime SetattrValid = 1 << 28
SetattrChgtime SetattrValid = 1 << 29
SetattrBkuptime SetattrValid = 1 << 30
SetattrFlags SetattrValid = 1 << 31
)
func (fl SetattrValid) Mode() bool { return fl&SetattrMode != 0 }
func (fl SetattrValid) Uid() bool { return fl&SetattrUid != 0 }
func (fl SetattrValid) Gid() bool { return fl&SetattrGid != 0 }
func (fl SetattrValid) Size() bool { return fl&SetattrSize != 0 }
func (fl SetattrValid) Atime() bool { return fl&SetattrAtime != 0 }
func (fl SetattrValid) Mtime() bool { return fl&SetattrMtime != 0 }
func (fl SetattrValid) Handle() bool { return fl&SetattrHandle != 0 }
func (fl SetattrValid) AtimeNow() bool { return fl&SetattrAtimeNow != 0 }
func (fl SetattrValid) MtimeNow() bool { return fl&SetattrMtimeNow != 0 }
func (fl SetattrValid) LockOwner() bool { return fl&SetattrLockOwner != 0 }
func (fl SetattrValid) Crtime() bool { return fl&SetattrCrtime != 0 }
func (fl SetattrValid) Chgtime() bool { return fl&SetattrChgtime != 0 }
func (fl SetattrValid) Bkuptime() bool { return fl&SetattrBkuptime != 0 }
func (fl SetattrValid) Flags() bool { return fl&SetattrFlags != 0 }
func (fl SetattrValid) String() string {
return flagString(uint32(fl), setattrValidNames)
}
var setattrValidNames = []flagName{
{uint32(SetattrMode), "SetattrMode"},
{uint32(SetattrUid), "SetattrUid"},
{uint32(SetattrGid), "SetattrGid"},
{uint32(SetattrSize), "SetattrSize"},
{uint32(SetattrAtime), "SetattrAtime"},
{uint32(SetattrMtime), "SetattrMtime"},
{uint32(SetattrHandle), "SetattrHandle"},
{uint32(SetattrAtimeNow), "SetattrAtimeNow"},
{uint32(SetattrMtimeNow), "SetattrMtimeNow"},
{uint32(SetattrLockOwner), "SetattrLockOwner"},
{uint32(SetattrCrtime), "SetattrCrtime"},
{uint32(SetattrChgtime), "SetattrChgtime"},
{uint32(SetattrBkuptime), "SetattrBkuptime"},
{uint32(SetattrFlags), "SetattrFlags"},
}
// Flags that can be seen in OpenRequest.Flags.
const (
// Access modes. These are not 1-bit flags, but alternatives where
// only one can be chosen. See the IsReadOnly etc convenience
// methods.
OpenReadOnly OpenFlags = syscall.O_RDONLY
OpenWriteOnly OpenFlags = syscall.O_WRONLY
OpenReadWrite OpenFlags = syscall.O_RDWR
// File was opened in append-only mode, all writes will go to end
// of file. OS X does not provide this information.
OpenAppend OpenFlags = syscall.O_APPEND
OpenCreate OpenFlags = syscall.O_CREAT
OpenDirectory OpenFlags = syscall.O_DIRECTORY
OpenExclusive OpenFlags = syscall.O_EXCL
OpenNonblock OpenFlags = syscall.O_NONBLOCK
OpenSync OpenFlags = syscall.O_SYNC
OpenTruncate OpenFlags = syscall.O_TRUNC
)
// OpenAccessModeMask is a bitmask that separates the access mode
// from the other flags in OpenFlags.
const OpenAccessModeMask OpenFlags = syscall.O_ACCMODE
// OpenFlags are the O_FOO flags passed to open/create/etc calls. For
// example, os.O_WRONLY | os.O_APPEND.
type OpenFlags uint32
func (fl OpenFlags) String() string {
// O_RDONLY, O_RWONLY, O_RDWR are not flags
s := accModeName(fl & OpenAccessModeMask)
flags := uint32(fl &^ OpenAccessModeMask)
if flags != 0 {
s = s + "+" + flagString(flags, openFlagNames)
}
return s
}
// Return true if OpenReadOnly is set.
func (fl OpenFlags) IsReadOnly() bool {
return fl&OpenAccessModeMask == OpenReadOnly
}
// Return true if OpenWriteOnly is set.
func (fl OpenFlags) IsWriteOnly() bool {
return fl&OpenAccessModeMask == OpenWriteOnly
}
// Return true if OpenReadWrite is set.
func (fl OpenFlags) IsReadWrite() bool {
return fl&OpenAccessModeMask == OpenReadWrite
}
func accModeName(flags OpenFlags) string {
switch flags {
case OpenReadOnly:
return "OpenReadOnly"
case OpenWriteOnly:
return "OpenWriteOnly"
case OpenReadWrite:
return "OpenReadWrite"
default:
return ""
}
}
var openFlagNames = []flagName{
{uint32(OpenAppend), "OpenAppend"},
{uint32(OpenCreate), "OpenCreate"},
{uint32(OpenDirectory), "OpenDirectory"},
{uint32(OpenExclusive), "OpenExclusive"},
{uint32(OpenNonblock), "OpenNonblock"},
{uint32(OpenSync), "OpenSync"},
{uint32(OpenTruncate), "OpenTruncate"},
}
// The OpenResponseFlags are returned in the OpenResponse.
type OpenResponseFlags uint32
const (
OpenDirectIO OpenResponseFlags = 1 << 0 // bypass page cache for this open file
OpenKeepCache OpenResponseFlags = 1 << 1 // don't invalidate the data cache on open
OpenNonSeekable OpenResponseFlags = 1 << 2 // mark the file as non-seekable (not supported on OS X)
OpenPurgeAttr OpenResponseFlags = 1 << 30 // OS X
OpenPurgeUBC OpenResponseFlags = 1 << 31 // OS X
)
func (fl OpenResponseFlags) String() string {
return flagString(uint32(fl), openResponseFlagNames)
}
var openResponseFlagNames = []flagName{
{uint32(OpenDirectIO), "OpenDirectIO"},
{uint32(OpenKeepCache), "OpenKeepCache"},
{uint32(OpenNonSeekable), "OpenNonSeekable"},
{uint32(OpenPurgeAttr), "OpenPurgeAttr"},
{uint32(OpenPurgeUBC), "OpenPurgeUBC"},
}
// The InitFlags are used in the Init exchange.
type InitFlags uint32
const (
InitAsyncRead InitFlags = 1 << 0
InitPosixLocks InitFlags = 1 << 1
InitFileOps InitFlags = 1 << 2
InitAtomicTrunc InitFlags = 1 << 3
InitExportSupport InitFlags = 1 << 4
InitBigWrites InitFlags = 1 << 5
// Do not mask file access modes with umask. Not supported on OS X.
InitDontMask InitFlags = 1 << 6
InitSpliceWrite InitFlags = 1 << 7
InitSpliceMove InitFlags = 1 << 8
InitSpliceRead InitFlags = 1 << 9
InitFlockLocks InitFlags = 1 << 10
InitHasIoctlDir InitFlags = 1 << 11
InitAutoInvalData InitFlags = 1 << 12
InitDoReaddirplus InitFlags = 1 << 13
InitReaddirplusAuto InitFlags = 1 << 14
InitAsyncDIO InitFlags = 1 << 15
InitWritebackCache InitFlags = 1 << 16
InitNoOpenSupport InitFlags = 1 << 17
InitCaseSensitive InitFlags = 1 << 29 // OS X only
InitVolRename InitFlags = 1 << 30 // OS X only
InitXtimes InitFlags = 1 << 31 // OS X only
)
type flagName struct {
bit uint32
name string
}
var initFlagNames = []flagName{
{uint32(InitAsyncRead), "InitAsyncRead"},
{uint32(InitPosixLocks), "InitPosixLocks"},
{uint32(InitFileOps), "InitFileOps"},
{uint32(InitAtomicTrunc), "InitAtomicTrunc"},
{uint32(InitExportSupport), "InitExportSupport"},
{uint32(InitBigWrites), "InitBigWrites"},
{uint32(InitDontMask), "InitDontMask"},
{uint32(InitSpliceWrite), "InitSpliceWrite"},
{uint32(InitSpliceMove), "InitSpliceMove"},
{uint32(InitSpliceRead), "InitSpliceRead"},
{uint32(InitFlockLocks), "InitFlockLocks"},
{uint32(InitHasIoctlDir), "InitHasIoctlDir"},
{uint32(InitAutoInvalData), "InitAutoInvalData"},
{uint32(InitDoReaddirplus), "InitDoReaddirplus"},
{uint32(InitReaddirplusAuto), "InitReaddirplusAuto"},
{uint32(InitAsyncDIO), "InitAsyncDIO"},
{uint32(InitWritebackCache), "InitWritebackCache"},
{uint32(InitNoOpenSupport), "InitNoOpenSupport"},
{uint32(InitCaseSensitive), "InitCaseSensitive"},
{uint32(InitVolRename), "InitVolRename"},
{uint32(InitXtimes), "InitXtimes"},
}
func (fl InitFlags) String() string {
return flagString(uint32(fl), initFlagNames)
}
func flagString(f uint32, names []flagName) string {
var s string
if f == 0 {
return "0"
}
for _, n := range names {
if f&n.bit != 0 {
s += "+" + n.name
f &^= n.bit
}
}
if f != 0 {
s += fmt.Sprintf("%+#x", f)
}
return s[1:]
}
// The ReleaseFlags are used in the Release exchange.
type ReleaseFlags uint32
const (
ReleaseFlush ReleaseFlags = 1 << 0
)
func (fl ReleaseFlags) String() string {
return flagString(uint32(fl), releaseFlagNames)
}
var releaseFlagNames = []flagName{
{uint32(ReleaseFlush), "ReleaseFlush"},
}
// Opcodes
const (
opLookup = 1
opForget = 2 // no reply
opGetattr = 3
opSetattr = 4
opReadlink = 5
opSymlink = 6
opMknod = 8
opMkdir = 9
opUnlink = 10
opRmdir = 11
opRename = 12
opLink = 13
opOpen = 14
opRead = 15
opWrite = 16
opStatfs = 17
opRelease = 18
opFsync = 20
opSetxattr = 21
opGetxattr = 22
opListxattr = 23
opRemovexattr = 24
opFlush = 25
opInit = 26
opOpendir = 27
opReaddir = 28
opReleasedir = 29
opFsyncdir = 30
opGetlk = 31
opSetlk = 32
opSetlkw = 33
opAccess = 34
opCreate = 35
opInterrupt = 36
opBmap = 37
opDestroy = 38
opIoctl = 39 // Linux?
opPoll = 40 // Linux?
// OS X
opSetvolname = 61
opGetxtimes = 62
opExchange = 63
)
type entryOut struct {
Nodeid uint64 // Inode ID
Generation uint64 // Inode generation
EntryValid uint64 // Cache timeout for the name
AttrValid uint64 // Cache timeout for the attributes
EntryValidNsec uint32
AttrValidNsec uint32
Attr attr
}
func entryOutSize(p Protocol) uintptr {
switch {
case p.LT(Protocol{7, 9}):
return unsafe.Offsetof(entryOut{}.Attr) + unsafe.Offsetof(entryOut{}.Attr.Blksize)
default:
return unsafe.Sizeof(entryOut{})
}
}
type forgetIn struct {
Nlookup uint64
}
type getattrIn struct {
GetattrFlags uint32
_ uint32
Fh uint64
}
type attrOut struct {
AttrValid uint64 // Cache timeout for the attributes
AttrValidNsec uint32
_ uint32
Attr attr
}
func attrOutSize(p Protocol) uintptr {
switch {
case p.LT(Protocol{7, 9}):
return unsafe.Offsetof(attrOut{}.Attr) + unsafe.Offsetof(attrOut{}.Attr.Blksize)
default:
return unsafe.Sizeof(attrOut{})
}
}
// OS X
type getxtimesOut struct {
Bkuptime uint64
Crtime uint64
BkuptimeNsec uint32
CrtimeNsec uint32
}
type mknodIn struct {
Mode uint32
Rdev uint32
Umask uint32
_ uint32
// "filename\x00" follows.
}
func mknodInSize(p Protocol) uintptr {
switch {
case p.LT(Protocol{7, 12}):
return unsafe.Offsetof(mknodIn{}.Umask)
default:
return unsafe.Sizeof(mknodIn{})
}
}
type mkdirIn struct {
Mode uint32
Umask uint32
// filename follows
}
func mkdirInSize(p Protocol) uintptr {
switch {
case p.LT(Protocol{7, 12}):
return unsafe.Offsetof(mkdirIn{}.Umask) + 4
default:
return unsafe.Sizeof(mkdirIn{})
}
}
type renameIn struct {
Newdir uint64
// "oldname\x00newname\x00" follows
}
// OS X
type exchangeIn struct {
Olddir uint64
Newdir uint64
Options uint64
// "oldname\x00newname\x00" follows
}
type linkIn struct {
Oldnodeid uint64
}
type setattrInCommon struct {
Valid uint32
_ uint32
Fh uint64
Size uint64
LockOwner uint64 // unused on OS X?
Atime uint64
Mtime uint64
Unused2 uint64
AtimeNsec uint32
MtimeNsec uint32
Unused3 uint32
Mode uint32
Unused4 uint32
Uid uint32
Gid uint32
Unused5 uint32
}
type openIn struct {
Flags uint32
Unused uint32
}
type openOut struct {
Fh uint64
OpenFlags uint32
_ uint32
}
type createIn struct {
Flags uint32
Mode uint32
Umask uint32
_ uint32
}
func createInSize(p Protocol) uintptr {
switch {
case p.LT(Protocol{7, 12}):
return unsafe.Offsetof(createIn{}.Umask)
default:
return unsafe.Sizeof(createIn{})
}
}
type releaseIn struct {
Fh uint64
Flags uint32
ReleaseFlags uint32
LockOwner uint32
}
type flushIn struct {
Fh uint64
FlushFlags uint32
_ uint32
LockOwner uint64
}
type readIn struct {
Fh uint64
Offset uint64
Size uint32
ReadFlags uint32
LockOwner uint64
Flags uint32
_ uint32
}
func readInSize(p Protocol) uintptr {
switch {
case p.LT(Protocol{7, 9}):
return unsafe.Offsetof(readIn{}.ReadFlags) + 4
default:
return unsafe.Sizeof(readIn{})
}
}
// The ReadFlags are passed in ReadRequest.
type ReadFlags uint32
const (
// LockOwner field is valid.
ReadLockOwner ReadFlags = 1 << 1
)
var readFlagNames = []flagName{
{uint32(ReadLockOwner), "ReadLockOwner"},
}
func (fl ReadFlags) String() string {
return flagString(uint32(fl), readFlagNames)
}
type writeIn struct {
Fh uint64
Offset uint64
Size uint32
WriteFlags uint32
LockOwner uint64
Flags uint32
_ uint32
}
func writeInSize(p Protocol) uintptr {
switch {
case p.LT(Protocol{7, 9}):
return unsafe.Offsetof(writeIn{}.LockOwner)
default:
return unsafe.Sizeof(writeIn{})
}
}
type writeOut struct {
Size uint32
_ uint32
}
// The WriteFlags are passed in WriteRequest.
type WriteFlags uint32
const (
WriteCache WriteFlags = 1 << 0
// LockOwner field is valid.
WriteLockOwner WriteFlags = 1 << 1
)
var writeFlagNames = []flagName{
{uint32(WriteCache), "WriteCache"},
{uint32(WriteLockOwner), "WriteLockOwner"},
}
func (fl WriteFlags) String() string {
return flagString(uint32(fl), writeFlagNames)
}
const compatStatfsSize = 48
type statfsOut struct {
St kstatfs
}
type fsyncIn struct {
Fh uint64
FsyncFlags uint32
_ uint32
}
type setxattrInCommon struct {
Size uint32
Flags uint32
}
func (setxattrInCommon) position() uint32 {
return 0
}
type getxattrInCommon struct {
Size uint32
_ uint32
}
func (getxattrInCommon) position() uint32 {
return 0
}
type getxattrOut struct {
Size uint32
_ uint32
}
type lkIn struct {
Fh uint64
Owner uint64
Lk fileLock
LkFlags uint32
_ uint32
}
func lkInSize(p Protocol) uintptr {
switch {
case p.LT(Protocol{7, 9}):
return unsafe.Offsetof(lkIn{}.LkFlags)
default:
return unsafe.Sizeof(lkIn{})
}
}
type lkOut struct {
Lk fileLock
}
type accessIn struct {
Mask uint32
_ uint32
}
type initIn struct {
Major uint32
Minor uint32
MaxReadahead uint32
Flags uint32
}
const initInSize = int(unsafe.Sizeof(initIn{}))
type initOut struct {
Major uint32
Minor uint32
MaxReadahead uint32
Flags uint32
Unused uint32
MaxWrite uint32
}
type interruptIn struct {
Unique uint64
}
type bmapIn struct {
Block uint64
BlockSize uint32
_ uint32
}
type bmapOut struct {
Block uint64
}
type inHeader struct {
Len uint32
Opcode uint32
Unique uint64
Nodeid uint64
Uid uint32
Gid uint32
Pid uint32
_ uint32
}
const inHeaderSize = int(unsafe.Sizeof(inHeader{}))
type outHeader struct {
Len uint32
Error int32
Unique uint64
}
type dirent struct {
Ino uint64
Off uint64
Namelen uint32
Type uint32
Name [0]byte
}
const direntSize = 8 + 8 + 4 + 4
const (
notifyCodePoll int32 = 1
notifyCodeInvalInode int32 = 2
notifyCodeInvalEntry int32 = 3
)
type notifyInvalInodeOut struct {
Ino uint64
Off int64
Len int64
}
type notifyInvalEntryOut struct {
Parent uint64
Namelen uint32
_ uint32
}
package fuse
import (
"time"
)
type attr struct {
Ino uint64
Size uint64
Blocks uint64
Atime uint64
Mtime uint64
Ctime uint64
Crtime_ uint64 // OS X only
AtimeNsec uint32
MtimeNsec uint32
CtimeNsec uint32
CrtimeNsec uint32 // OS X only
Mode uint32
Nlink uint32
Uid uint32
Gid uint32
Rdev uint32
Flags_ uint32 // OS X only; see chflags(2)
Blksize uint32
padding uint32
}
func (a *attr) SetCrtime(s uint64, ns uint32) {
a.Crtime_, a.CrtimeNsec = s, ns
}
func (a *attr) SetFlags(f uint32) {
a.Flags_ = f
}
type setattrIn struct {
setattrInCommon
// OS X only
Bkuptime_ uint64
Chgtime_ uint64
Crtime uint64
BkuptimeNsec uint32
ChgtimeNsec uint32
CrtimeNsec uint32
Flags_ uint32 // see chflags(2)
}
func (in *setattrIn) BkupTime() time.Time {
return time.Unix(int64(in.Bkuptime_), int64(in.BkuptimeNsec))
}
func (in *setattrIn) Chgtime() time.Time {
return time.Unix(int64(in.Chgtime_), int64(in.ChgtimeNsec))
}
func (in *setattrIn) Flags() uint32 {
return in.Flags_
}
func openFlags(flags uint32) OpenFlags {
return OpenFlags(flags)
}
type getxattrIn struct {
getxattrInCommon
// OS X only
Position uint32
Padding uint32
}
func (g *getxattrIn) position() uint32 {
return g.Position
}
type setxattrIn struct {
setxattrInCommon
// OS X only
Position uint32
Padding uint32
}
func (s *setxattrIn) position() uint32 {
return s.Position
}
package fuse
import "time"
type attr struct {
Ino uint64
Size uint64
Blocks uint64
Atime uint64
Mtime uint64
Ctime uint64
AtimeNsec uint32
MtimeNsec uint32
CtimeNsec uint32
Mode uint32
Nlink uint32
Uid uint32
Gid uint32
Rdev uint32
Blksize uint32
padding uint32
}
func (a *attr) Crtime() time.Time {
return time.Time{}
}
func (a *attr) SetCrtime(s uint64, ns uint32) {
// ignored on freebsd
}
func (a *attr) SetFlags(f uint32) {
// ignored on freebsd
}
type setattrIn struct {
setattrInCommon
}
func (in *setattrIn) BkupTime() time.Time {
return time.Time{}
}
func (in *setattrIn) Chgtime() time.Time {
return time.Time{}
}
func (in *setattrIn) Flags() uint32 {
return 0
}
func openFlags(flags uint32) OpenFlags {
return OpenFlags(flags)
}
type getxattrIn struct {
getxattrInCommon
}
type setxattrIn struct {
setxattrInCommon
}
package fuse
import "time"
type attr struct {
Ino uint64
Size uint64
Blocks uint64
Atime uint64
Mtime uint64
Ctime uint64
AtimeNsec uint32
MtimeNsec uint32
CtimeNsec uint32
Mode uint32
Nlink uint32
Uid uint32
Gid uint32
Rdev uint32
Blksize uint32
padding uint32
}
func (a *attr) Crtime() time.Time {
return time.Time{}
}
func (a *attr) SetCrtime(s uint64, ns uint32) {
// Ignored on Linux.
}
func (a *attr) SetFlags(f uint32) {
// Ignored on Linux.
}
type setattrIn struct {
setattrInCommon
}
func (in *setattrIn) BkupTime() time.Time {
return time.Time{}
}
func (in *setattrIn) Chgtime() time.Time {
return time.Time{}
}
func (in *setattrIn) Flags() uint32 {
return 0
}
func openFlags(flags uint32) OpenFlags {
// on amd64, the 32-bit O_LARGEFILE flag is always seen;
// on i386, the flag probably depends on the app
// requesting, but in any case should be utterly
// uninteresting to us here; our kernel protocol messages
// are not directly related to the client app's kernel
// API/ABI
flags &^= 0x8000
return OpenFlags(flags)
}
type getxattrIn struct {
getxattrInCommon
}
type setxattrIn struct {
setxattrInCommon
}
package fuse
// Maximum file write size we are prepared to receive from the kernel.
//
// Linux 4.2.0 has been observed to cap this value at 128kB
// (FUSE_MAX_PAGES_PER_REQ=32, 4kB pages).
const maxWrite = 128 * 1024
package fuseutil // import "bazil.org/fuse/fuseutil"
import (
"bazil.org/fuse"
)
// HandleRead handles a read request assuming that data is the entire file content.
// It adjusts the amount returned in resp according to req.Offset and req.Size.
func HandleRead(req *fuse.ReadRequest, resp *fuse.ReadResponse, data []byte) {
if req.Offset >= int64(len(data)) {
data = nil
} else {
data = data[req.Offset:]
}
if len(data) > req.Size {
data = data[:req.Size]
}
n := copy(resp.Data[:req.Size], data)
resp.Data = resp.Data[:n]
}
package fuse
import (
"bufio"
"errors"
"io"
"log"
"sync"
)
var (
// ErrOSXFUSENotFound is returned from Mount when the OSXFUSE
// installation is not detected.
//
// Only happens on OS X. Make sure OSXFUSE is installed, or see
// OSXFUSELocations for customization.
ErrOSXFUSENotFound = errors.New("cannot locate OSXFUSE")
)
func neverIgnoreLine(line string) bool {
return false
}
func lineLogger(wg *sync.WaitGroup, prefix string, ignore func(line string) bool, r io.ReadCloser) {
defer wg.Done()
scanner := bufio.NewScanner(r)
for scanner.Scan() {
line := scanner.Text()
if ignore(line) {
continue
}
log.Printf("%s: %s", prefix, line)
}
if err := scanner.Err(); err != nil {
log.Printf("%s, error reading: %v", prefix, err)
}
}
package fuse
import (
"errors"
"fmt"
"log"
"os"
"os/exec"
"path"
"strconv"
"strings"
"sync"
"syscall"
)
var (
errNoAvail = errors.New("no available fuse devices")
errNotLoaded = errors.New("osxfuse is not loaded")
)
func loadOSXFUSE(bin string) error {
cmd := exec.Command(bin)
cmd.Dir = "/"
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
err := cmd.Run()
return err
}
func openOSXFUSEDev(devPrefix string) (*os.File, error) {
var f *os.File
var err error
for i := uint64(0); ; i++ {
path := devPrefix + strconv.FormatUint(i, 10)
f, err = os.OpenFile(path, os.O_RDWR, 0000)
if os.IsNotExist(err) {
if i == 0 {
// not even the first device was found -> fuse is not loaded
return nil, errNotLoaded
}
// we've run out of kernel-provided devices
return nil, errNoAvail
}
if err2, ok := err.(*os.PathError); ok && err2.Err == syscall.EBUSY {
// try the next one
continue
}
if err != nil {
return nil, err
}
return f, nil
}
}
func handleMountOSXFUSE(helperName string, errCh chan<- error) func(line string) (ignore bool) {
var noMountpointPrefix = helperName + `: `
const noMountpointSuffix = `: No such file or directory`
return func(line string) (ignore bool) {
if strings.HasPrefix(line, noMountpointPrefix) && strings.HasSuffix(line, noMountpointSuffix) {
// re-extract it from the error message in case some layer
// changed the path
mountpoint := line[len(noMountpointPrefix) : len(line)-len(noMountpointSuffix)]
err := &MountpointDoesNotExistError{
Path: mountpoint,
}
select {
case errCh <- err:
return true
default:
// not the first error; fall back to logging it
return false
}
}
return false
}
}
// isBoringMountOSXFUSEError returns whether the Wait error is
// uninteresting; exit status 64 is.
func isBoringMountOSXFUSEError(err error) bool {
if err, ok := err.(*exec.ExitError); ok && err.Exited() {
if status, ok := err.Sys().(syscall.WaitStatus); ok && status.ExitStatus() == 64 {
return true
}
}
return false
}
func callMount(bin string, daemonVar string, dir string, conf *mountConfig, f *os.File, ready chan<- struct{}, errp *error) error {
for k, v := range conf.options {
if strings.Contains(k, ",") || strings.Contains(v, ",") {
// Silly limitation but the mount helper does not
// understand any escaping. See TestMountOptionCommaError.
return fmt.Errorf("mount options cannot contain commas on darwin: %q=%q", k, v)
}
}
cmd := exec.Command(
bin,
"-o", conf.getOptions(),
// Tell osxfuse-kext how large our buffer is. It must split
// writes larger than this into multiple writes.
//
// OSXFUSE seems to ignore InitResponse.MaxWrite, and uses
// this instead.
"-o", "iosize="+strconv.FormatUint(maxWrite, 10),
// refers to fd passed in cmd.ExtraFiles
"3",
dir,
)
cmd.ExtraFiles = []*os.File{f}
cmd.Env = os.Environ()
// OSXFUSE <3.3.0
cmd.Env = append(cmd.Env, "MOUNT_FUSEFS_CALL_BY_LIB=")
// OSXFUSE >=3.3.0
cmd.Env = append(cmd.Env, "MOUNT_OSXFUSE_CALL_BY_LIB=")
daemon := os.Args[0]
if daemonVar != "" {
cmd.Env = append(cmd.Env, daemonVar+"="+daemon)
}
stdout, err := cmd.StdoutPipe()
if err != nil {
return fmt.Errorf("setting up mount_osxfusefs stderr: %v", err)
}
stderr, err := cmd.StderrPipe()
if err != nil {
return fmt.Errorf("setting up mount_osxfusefs stderr: %v", err)
}
if err := cmd.Start(); err != nil {
return fmt.Errorf("mount_osxfusefs: %v", err)
}
helperErrCh := make(chan error, 1)
go func() {
var wg sync.WaitGroup
wg.Add(2)
go lineLogger(&wg, "mount helper output", neverIgnoreLine, stdout)
helperName := path.Base(bin)
go lineLogger(&wg, "mount helper error", handleMountOSXFUSE(helperName, helperErrCh), stderr)
wg.Wait()
if err := cmd.Wait(); err != nil {
// see if we have a better error to report
select {
case helperErr := <-helperErrCh:
// log the Wait error if it's not what we expected
if !isBoringMountOSXFUSEError(err) {
log.Printf("mount helper failed: %v", err)
}
// and now return what we grabbed from stderr as the real
// error
*errp = helperErr
close(ready)
return
default:
// nope, fall back to generic message
}
*errp = fmt.Errorf("mount_osxfusefs: %v", err)
close(ready)
return
}
*errp = nil
close(ready)
}()
return nil
}
func mount(dir string, conf *mountConfig, ready chan<- struct{}, errp *error) (*os.File, error) {
locations := conf.osxfuseLocations
if locations == nil {
locations = []OSXFUSEPaths{
OSXFUSELocationV3,
OSXFUSELocationV2,
}
}
for _, loc := range locations {
if _, err := os.Stat(loc.Mount); os.IsNotExist(err) {
// try the other locations
continue
}
f, err := openOSXFUSEDev(loc.DevicePrefix)
if err == errNotLoaded {
err = loadOSXFUSE(loc.Load)
if err != nil {
return nil, err
}
// try again
f, err = openOSXFUSEDev(loc.DevicePrefix)
}
if err != nil {
return nil, err
}
err = callMount(loc.Mount, loc.DaemonVar, dir, conf, f, ready, errp)
if err != nil {
f.Close()
return nil, err
}
return f, nil
}
return nil, ErrOSXFUSENotFound
}
package fuse
import (
"fmt"
"log"
"os"
"os/exec"
"strings"
"sync"
"syscall"
)
func handleMountFusefsStderr(errCh chan<- error) func(line string) (ignore bool) {
return func(line string) (ignore bool) {
const (
noMountpointPrefix = `mount_fusefs: `
noMountpointSuffix = `: No such file or directory`
)
if strings.HasPrefix(line, noMountpointPrefix) && strings.HasSuffix(line, noMountpointSuffix) {
// re-extract it from the error message in case some layer
// changed the path
mountpoint := line[len(noMountpointPrefix) : len(line)-len(noMountpointSuffix)]
err := &MountpointDoesNotExistError{
Path: mountpoint,
}
select {
case errCh <- err:
return true
default:
// not the first error; fall back to logging it
return false
}
}
return false
}
}
// isBoringMountFusefsError returns whether the Wait error is
// uninteresting; exit status 1 is.
func isBoringMountFusefsError(err error) bool {
if err, ok := err.(*exec.ExitError); ok && err.Exited() {
if status, ok := err.Sys().(syscall.WaitStatus); ok && status.ExitStatus() == 1 {
return true
}
}
return false
}
func mount(dir string, conf *mountConfig, ready chan<- struct{}, errp *error) (*os.File, error) {
for k, v := range conf.options {
if strings.Contains(k, ",") || strings.Contains(v, ",") {
// Silly limitation but the mount helper does not
// understand any escaping. See TestMountOptionCommaError.
return nil, fmt.Errorf("mount options cannot contain commas on FreeBSD: %q=%q", k, v)
}
}
f, err := os.OpenFile("/dev/fuse", os.O_RDWR, 0000)
if err != nil {
*errp = err
return nil, err
}
cmd := exec.Command(
"/sbin/mount_fusefs",
"--safe",
"-o", conf.getOptions(),
"3",
dir,
)
cmd.ExtraFiles = []*os.File{f}
stdout, err := cmd.StdoutPipe()
if err != nil {
return nil, fmt.Errorf("setting up mount_fusefs stderr: %v", err)
}
stderr, err := cmd.StderrPipe()
if err != nil {
return nil, fmt.Errorf("setting up mount_fusefs stderr: %v", err)
}
if err := cmd.Start(); err != nil {
return nil, fmt.Errorf("mount_fusefs: %v", err)
}
helperErrCh := make(chan error, 1)
var wg sync.WaitGroup
wg.Add(2)
go lineLogger(&wg, "mount helper output", neverIgnoreLine, stdout)
go lineLogger(&wg, "mount helper error", handleMountFusefsStderr(helperErrCh), stderr)
wg.Wait()
if err := cmd.Wait(); err != nil {
// see if we have a better error to report
select {
case helperErr := <-helperErrCh:
// log the Wait error if it's not what we expected
if !isBoringMountFusefsError(err) {
log.Printf("mount helper failed: %v", err)
}
// and now return what we grabbed from stderr as the real
// error
return nil, helperErr
default:
// nope, fall back to generic message
}
return nil, fmt.Errorf("mount_fusefs: %v", err)
}
close(ready)
return f, nil
}
package fuse
import (
"fmt"
"log"
"net"
"os"
"os/exec"
"strings"
"sync"
"syscall"
)
func handleFusermountStderr(errCh chan<- error) func(line string) (ignore bool) {
return func(line string) (ignore bool) {
if line == `fusermount: failed to open /etc/fuse.conf: Permission denied` {
// Silence this particular message, it occurs way too
// commonly and isn't very relevant to whether the mount
// succeeds or not.
return true
}
const (
noMountpointPrefix = `fusermount: failed to access mountpoint `
noMountpointSuffix = `: No such file or directory`
)
if strings.HasPrefix(line, noMountpointPrefix) && strings.HasSuffix(line, noMountpointSuffix) {
// re-extract it from the error message in case some layer
// changed the path
mountpoint := line[len(noMountpointPrefix) : len(line)-len(noMountpointSuffix)]
err := &MountpointDoesNotExistError{
Path: mountpoint,
}
select {
case errCh <- err:
return true
default:
// not the first error; fall back to logging it
return false
}
}
return false
}
}
// isBoringFusermountError returns whether the Wait error is
// uninteresting; exit status 1 is.
func isBoringFusermountError(err error) bool {
if err, ok := err.(*exec.ExitError); ok && err.Exited() {
if status, ok := err.Sys().(syscall.WaitStatus); ok && status.ExitStatus() == 1 {
return true
}
}
return false
}
func mount(dir string, conf *mountConfig, ready chan<- struct{}, errp *error) (fusefd *os.File, err error) {
// linux mount is never delayed
close(ready)
fds, err := syscall.Socketpair(syscall.AF_FILE, syscall.SOCK_STREAM, 0)
if err != nil {
return nil, fmt.Errorf("socketpair error: %v", err)
}
writeFile := os.NewFile(uintptr(fds[0]), "fusermount-child-writes")
defer writeFile.Close()
readFile := os.NewFile(uintptr(fds[1]), "fusermount-parent-reads")
defer readFile.Close()
cmd := exec.Command(
"fusermount",
"-o", conf.getOptions(),
"--",
dir,
)
cmd.Env = append(os.Environ(), "_FUSE_COMMFD=3")
cmd.ExtraFiles = []*os.File{writeFile}
var wg sync.WaitGroup
stdout, err := cmd.StdoutPipe()
if err != nil {
return nil, fmt.Errorf("setting up fusermount stderr: %v", err)
}
stderr, err := cmd.StderrPipe()
if err != nil {
return nil, fmt.Errorf("setting up fusermount stderr: %v", err)
}
if err := cmd.Start(); err != nil {
return nil, fmt.Errorf("fusermount: %v", err)
}
helperErrCh := make(chan error, 1)
wg.Add(2)
go lineLogger(&wg, "mount helper output", neverIgnoreLine, stdout)
go lineLogger(&wg, "mount helper error", handleFusermountStderr(helperErrCh), stderr)
wg.Wait()
if err := cmd.Wait(); err != nil {
// see if we have a better error to report
select {
case helperErr := <-helperErrCh:
// log the Wait error if it's not what we expected
if !isBoringFusermountError(err) {
log.Printf("mount helper failed: %v", err)
}
// and now return what we grabbed from stderr as the real
// error
return nil, helperErr
default:
// nope, fall back to generic message
}
return nil, fmt.Errorf("fusermount: %v", err)
}
c, err := net.FileConn(readFile)
if err != nil {
return nil, fmt.Errorf("FileConn from fusermount socket: %v", err)
}
defer c.Close()
uc, ok := c.(*net.UnixConn)
if !ok {
return nil, fmt.Errorf("unexpected FileConn type; expected UnixConn, got %T", c)
}
buf := make([]byte, 32) // expect 1 byte
oob := make([]byte, 32) // expect 24 bytes
_, oobn, _, _, err := uc.ReadMsgUnix(buf, oob)
scms, err := syscall.ParseSocketControlMessage(oob[:oobn])
if err != nil {
return nil, fmt.Errorf("ParseSocketControlMessage: %v", err)
}
if len(scms) != 1 {
return nil, fmt.Errorf("expected 1 SocketControlMessage; got scms = %#v", scms)
}
scm := scms[0]
gotFds, err := syscall.ParseUnixRights(&scm)
if err != nil {
return nil, fmt.Errorf("syscall.ParseUnixRights: %v", err)
}
if len(gotFds) != 1 {
return nil, fmt.Errorf("wanted 1 fd; got %#v", gotFds)
}
f := os.NewFile(uintptr(gotFds[0]), "/dev/fuse")
return f, nil
}
package fuse
import (
"errors"
"strings"
)
func dummyOption(conf *mountConfig) error {
return nil
}
// mountConfig holds the configuration for a mount operation.
// Use it by passing MountOption values to Mount.
type mountConfig struct {
options map[string]string
maxReadahead uint32
initFlags InitFlags
osxfuseLocations []OSXFUSEPaths
}
func escapeComma(s string) string {
s = strings.Replace(s, `\`, `\\`, -1)
s = strings.Replace(s, `,`, `\,`, -1)
return s
}
// getOptions makes a string of options suitable for passing to FUSE
// mount flag `-o`. Returns an empty string if no options were set.
// Any platform specific adjustments should happen before the call.
func (m *mountConfig) getOptions() string {
var opts []string
for k, v := range m.options {
k = escapeComma(k)
if v != "" {
k += "=" + escapeComma(v)
}
opts = append(opts, k)
}
return strings.Join(opts, ",")
}
type mountOption func(*mountConfig) error
// MountOption is passed to Mount to change the behavior of the mount.
type MountOption mountOption
// FSName sets the file system name (also called source) that is
// visible in the list of mounted file systems.
//
// FreeBSD ignores this option.
func FSName(name string) MountOption {
return func(conf *mountConfig) error {
conf.options["fsname"] = name
return nil
}
}
// Subtype sets the subtype of the mount. The main type is always
// `fuse`. The type in a list of mounted file systems will look like
// `fuse.foo`.
//
// OS X ignores this option.
// FreeBSD ignores this option.
func Subtype(fstype string) MountOption {
return func(conf *mountConfig) error {
conf.options["subtype"] = fstype
return nil
}
}
// LocalVolume sets the volume to be local (instead of network),
// changing the behavior of Finder, Spotlight, and such.
//
// OS X only. Others ignore this option.
func LocalVolume() MountOption {
return localVolume
}
// VolumeName sets the volume name shown in Finder.
//
// OS X only. Others ignore this option.
func VolumeName(name string) MountOption {
return volumeName(name)
}
// NoAppleDouble makes OSXFUSE disallow files with names used by OS X
// to store extended attributes on file systems that do not support
// them natively.
//
// Such file names are:
//
// ._*
// .DS_Store
//
// OS X only. Others ignore this option.
func NoAppleDouble() MountOption {
return noAppleDouble
}
// NoAppleXattr makes OSXFUSE disallow extended attributes with the
// prefix "com.apple.". This disables persistent Finder state and
// other such information.
//
// OS X only. Others ignore this option.
func NoAppleXattr() MountOption {
return noAppleXattr
}
// ExclCreate causes O_EXCL flag to be set for only "truly" exclusive creates,
// i.e. create calls for which the initiator explicitly set the O_EXCL flag.
//
// OSXFUSE expects all create calls to return EEXIST in case the file
// already exists, regardless of whether O_EXCL was specified or not.
// To ensure this behavior, it normally sets OpenExclusive for all
// Create calls, regardless of whether the original call had it set.
// For distributed filesystems, that may force every file create to be
// a distributed consensus action, causing undesirable delays.
//
// This option makes the FUSE filesystem see the original flag value,
// and better decide when to ensure global consensus.
//
// Note that returning EEXIST on existing file create is still
// expected with OSXFUSE, regardless of the presence of the
// OpenExclusive flag.
//
// For more information, see
// https://github.com/osxfuse/osxfuse/issues/209
//
// OS X only. Others ignore this options.
// Requires OSXFUSE 3.4.1 or newer.
func ExclCreate() MountOption {
return exclCreate
}
// DaemonTimeout sets the time in seconds between a request and a reply before
// the FUSE mount is declared dead.
//
// OS X and FreeBSD only. Others ignore this option.
func DaemonTimeout(name string) MountOption {
return daemonTimeout(name)
}
var ErrCannotCombineAllowOtherAndAllowRoot = errors.New("cannot combine AllowOther and AllowRoot")
// AllowOther allows other users to access the file system.
//
// Only one of AllowOther or AllowRoot can be used.
func AllowOther() MountOption {
return func(conf *mountConfig) error {
if _, ok := conf.options["allow_root"]; ok {
return ErrCannotCombineAllowOtherAndAllowRoot
}
conf.options["allow_other"] = ""
return nil
}
}
// AllowRoot allows other users to access the file system.
//
// Only one of AllowOther or AllowRoot can be used.
//
// FreeBSD ignores this option.
func AllowRoot() MountOption {
return func(conf *mountConfig) error {
if _, ok := conf.options["allow_other"]; ok {
return ErrCannotCombineAllowOtherAndAllowRoot
}
conf.options["allow_root"] = ""
return nil
}
}
// AllowDev enables interpreting character or block special devices on the
// filesystem.
func AllowDev() MountOption {
return func(conf *mountConfig) error {
conf.options["dev"] = ""
return nil
}
}
// AllowSUID allows set-user-identifier or set-group-identifier bits to take
// effect.
func AllowSUID() MountOption {
return func(conf *mountConfig) error {
conf.options["suid"] = ""
return nil
}
}
// DefaultPermissions makes the kernel enforce access control based on
// the file mode (as in chmod).
//
// Without this option, the Node itself decides what is and is not
// allowed. This is normally ok because FUSE file systems cannot be
// accessed by other users without AllowOther/AllowRoot.
//
// FreeBSD ignores this option.
func DefaultPermissions() MountOption {
return func(conf *mountConfig) error {
conf.options["default_permissions"] = ""
return nil
}
}
// ReadOnly makes the mount read-only.
func ReadOnly() MountOption {
return func(conf *mountConfig) error {
conf.options["ro"] = ""
return nil
}
}
// MaxReadahead sets the number of bytes that can be prefetched for
// sequential reads. The kernel can enforce a maximum value lower than
// this.
//
// This setting makes the kernel perform speculative reads that do not
// originate from any client process. This usually tremendously
// improves read performance.
func MaxReadahead(n uint32) MountOption {
return func(conf *mountConfig) error {
conf.maxReadahead = n
return nil
}
}
// AsyncRead enables multiple outstanding read requests for the same
// handle. Without this, there is at most one request in flight at a
// time.
func AsyncRead() MountOption {
return func(conf *mountConfig) error {
conf.initFlags |= InitAsyncRead
return nil
}
}
// WritebackCache enables the kernel to buffer writes before sending
// them to the FUSE server. Without this, writethrough caching is
// used.
func WritebackCache() MountOption {
return func(conf *mountConfig) error {
conf.initFlags |= InitWritebackCache
return nil
}
}
// OSXFUSEPaths describes the paths used by an installed OSXFUSE
// version. See OSXFUSELocationV3 for typical values.
type OSXFUSEPaths struct {
// Prefix for the device file. At mount time, an incrementing
// number is suffixed until a free FUSE device is found.
DevicePrefix string
// Path of the load helper, used to load the kernel extension if
// no device files are found.
Load string
// Path of the mount helper, used for the actual mount operation.
Mount string
// Environment variable used to pass the path to the executable
// calling the mount helper.
DaemonVar string
}
// Default paths for OSXFUSE. See OSXFUSELocations.
var (
OSXFUSELocationV3 = OSXFUSEPaths{
DevicePrefix: "/dev/osxfuse",
Load: "/Library/Filesystems/osxfuse.fs/Contents/Resources/load_osxfuse",
Mount: "/Library/Filesystems/osxfuse.fs/Contents/Resources/mount_osxfuse",
DaemonVar: "MOUNT_OSXFUSE_DAEMON_PATH",
}
OSXFUSELocationV2 = OSXFUSEPaths{
DevicePrefix: "/dev/osxfuse",
Load: "/Library/Filesystems/osxfusefs.fs/Support/load_osxfusefs",
Mount: "/Library/Filesystems/osxfusefs.fs/Support/mount_osxfusefs",
DaemonVar: "MOUNT_FUSEFS_DAEMON_PATH",
}
)
// OSXFUSELocations sets where to look for OSXFUSE files. The
// arguments are all the possible locations. The previous locations
// are replaced.
//
// Without this option, OSXFUSELocationV3 and OSXFUSELocationV2 are
// used.
//
// OS X only. Others ignore this option.
func OSXFUSELocations(paths ...OSXFUSEPaths) MountOption {
return func(conf *mountConfig) error {
if len(paths) == 0 {
return errors.New("must specify at least one location for OSXFUSELocations")
}
// replace previous values, but make a copy so there's no
// worries about caller mutating their slice
conf.osxfuseLocations = append(conf.osxfuseLocations[:0], paths...)
return nil
}
}
// AllowNonEmptyMount allows the mounting over a non-empty directory.
//
// The files in it will be shadowed by the freshly created mount. By
// default these mounts are rejected to prevent accidental covering up
// of data, which could for example prevent automatic backup.
func AllowNonEmptyMount() MountOption {
return func(conf *mountConfig) error {
conf.options["nonempty"] = ""
return nil
}
}
package fuse
func localVolume(conf *mountConfig) error {
conf.options["local"] = ""
return nil
}
func volumeName(name string) MountOption {
return func(conf *mountConfig) error {
conf.options["volname"] = name
return nil
}
}
func daemonTimeout(name string) MountOption {
return func(conf *mountConfig) error {
conf.options["daemon_timeout"] = name
return nil
}
}
func noAppleXattr(conf *mountConfig) error {
conf.options["noapplexattr"] = ""
return nil
}
func noAppleDouble(conf *mountConfig) error {
conf.options["noappledouble"] = ""
return nil
}
func exclCreate(conf *mountConfig) error {
conf.options["excl_create"] = ""
return nil
}
package fuse
func localVolume(conf *mountConfig) error {
return nil
}
func volumeName(name string) MountOption {
return dummyOption
}
func daemonTimeout(name string) MountOption {
return func(conf *mountConfig) error {
conf.options["timeout"] = name
return nil
}
}
func noAppleXattr(conf *mountConfig) error {
return nil
}
func noAppleDouble(conf *mountConfig) error {
return nil
}
func exclCreate(conf *mountConfig) error {
return nil
}
package fuse
func localVolume(conf *mountConfig) error {
return nil
}
func volumeName(name string) MountOption {
return dummyOption
}
func daemonTimeout(name string) MountOption {
return dummyOption
}
func noAppleXattr(conf *mountConfig) error {
return nil
}
func noAppleDouble(conf *mountConfig) error {
return nil
}
func exclCreate(conf *mountConfig) error {
return nil
}
package fuse
import (
"fmt"
)
// Protocol is a FUSE protocol version number.
type Protocol struct {
Major uint32
Minor uint32
}
func (p Protocol) String() string {
return fmt.Sprintf("%d.%d", p.Major, p.Minor)
}
// LT returns whether a is less than b.
func (a Protocol) LT(b Protocol) bool {
return a.Major < b.Major ||
(a.Major == b.Major && a.Minor < b.Minor)
}
// GE returns whether a is greater than or equal to b.
func (a Protocol) GE(b Protocol) bool {
return a.Major > b.Major ||
(a.Major == b.Major && a.Minor >= b.Minor)
}
func (a Protocol) is79() bool {
return a.GE(Protocol{7, 9})
}
// HasAttrBlockSize returns whether Attr.BlockSize is respected by the
// kernel.
func (a Protocol) HasAttrBlockSize() bool {
return a.is79()
}
// HasReadWriteFlags returns whether ReadRequest/WriteRequest
// fields Flags and FileFlags are valid.
func (a Protocol) HasReadWriteFlags() bool {
return a.is79()
}
// HasGetattrFlags returns whether GetattrRequest field Flags is
// valid.
func (a Protocol) HasGetattrFlags() bool {
return a.is79()
}
func (a Protocol) is710() bool {
return a.GE(Protocol{7, 10})
}
// HasOpenNonSeekable returns whether OpenResponse field Flags flag
// OpenNonSeekable is supported.
func (a Protocol) HasOpenNonSeekable() bool {
return a.is710()
}
func (a Protocol) is712() bool {
return a.GE(Protocol{7, 12})
}
// HasUmask returns whether CreateRequest/MkdirRequest/MknodRequest
// field Umask is valid.
func (a Protocol) HasUmask() bool {
return a.is712()
}
// HasInvalidate returns whether InvalidateNode/InvalidateEntry are
// supported.
func (a Protocol) HasInvalidate() bool {
return a.is712()
}
package fuse
// Unmount tries to unmount the filesystem mounted at dir.
func Unmount(dir string) error {
return unmount(dir)
}
package fuse
import (
"bytes"
"errors"
"os/exec"
)
func unmount(dir string) error {
cmd := exec.Command("fusermount", "-u", dir)
output, err := cmd.CombinedOutput()
if err != nil {
if len(output) > 0 {
output = bytes.TrimRight(output, "\n")
msg := err.Error() + ": " + string(output)
err = errors.New(msg)
}
return err
}
return nil
}
// +build !linux
package fuse
import (
"os"
"syscall"
)
func unmount(dir string) error {
err := syscall.Unmount(dir, 0)
if err != nil {
err = &os.PathError{Op: "unmount", Path: dir, Err: err}
return err
}
return nil
}
......@@ -2,6 +2,24 @@
"comment": "",
"ignore": "test",
"package": [
{
"checksumSHA1": "b5bkSc2hlmUV7PlLY6JlLwiJpiE=",
"path": "bazil.org/fuse",
"revision": "371fbbdaa8987b715bdd21d6adc4c9b20155f748",
"revisionTime": "2016-08-11T21:22:31Z"
},
{
"checksumSHA1": "389JFJTJADMtZkTIfdSnsmHVOUs=",
"path": "bazil.org/fuse/fs",
"revision": "371fbbdaa8987b715bdd21d6adc4c9b20155f748",
"revisionTime": "2016-08-11T21:22:31Z"
},
{
"checksumSHA1": "NPgkh9UWMsaTtsAAs3kPrclHT9Y=",
"path": "bazil.org/fuse/fuseutil",
"revision": "371fbbdaa8987b715bdd21d6adc4c9b20155f748",
"revisionTime": "2016-08-11T21:22:31Z"
},
{
"checksumSHA1": "M30X+Wqn7AnUr1numUOkQRI7ET0=",
"path": "github.com/Azure/azure-sdk-for-go/storage",
......
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