op-geth/swarm/api/fuse.go

140 lines
3.4 KiB
Go

// 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
}