package fusefs import ( "bytes" "context" "io" "strconv" "syscall" "github.com/hanwen/go-fuse/v2/fs" "github.com/hanwen/go-fuse/v2/fuse" "go.arsenm.dev/infinitime" "go.arsenm.dev/infinitime/blefs" "go.arsenm.dev/logger/log" ) type ITProperty struct { name string Ino uint64 gen func() ([]byte, error) } type DirEntry struct { isDir bool modtime uint64 size uint32 path string } type ITNode struct { fs.Inode kind int Ino uint64 lst []DirEntry self DirEntry path string } var ( myfs *blefs.FS = nil inodemap map[string]uint64 = nil ) func BuildRootNode(dev *infinitime.Device) (*ITNode, error) { var err error inodemap = make(map[string]uint64) myfs, err = dev.FS() if err != nil { log.Error("FUSE Failed to get filesystem").Err(err).Send() return nil, err } return &ITNode{kind: 0}, nil } var properties = make([]ITProperty, 6) func BuildProperties(dev *infinitime.Device) { properties[0] = ITProperty{ "heartrate", 2, func() ([]byte, error) { ans, err := dev.HeartRate() return []byte(strconv.Itoa(int(ans)) + "\n"), err }, } properties[1] = ITProperty{ "battery", 3, func() ([]byte, error) { ans, err := dev.BatteryLevel() return []byte(strconv.Itoa(int(ans)) + "\n"), err }, } properties[2] = ITProperty{ "motion", 4, func() ([]byte, error) { ans, err := dev.Motion() return []byte(strconv.Itoa(int(ans.X)) + " " + strconv.Itoa(int(ans.Y)) + " " + strconv.Itoa(int(ans.Z)) + "\n"), err }, } properties[3] = ITProperty{ "stepcount", 6, func() ([]byte, error) { ans, err := dev.StepCount() return []byte(strconv.Itoa(int(ans)) + "\n"), err }, } properties[4] = ITProperty{ "version", 7, func() ([]byte, error) { ans, err := dev.Version() return []byte(ans + "\n"), err }, } properties[5] = ITProperty{ "address", 8, func() ([]byte, error) { ans := dev.Address() return []byte(ans + "\n"), nil }, } } var _ fs.NodeReaddirer = (*ITNode)(nil) // Readdir is part of the NodeReaddirer interface func (n *ITNode) Readdir(ctx context.Context) (fs.DirStream, syscall.Errno) { switch n.kind { case 0: // root folder r := make([]fuse.DirEntry, 2) r[0] = fuse.DirEntry{ Name: "info", Ino: 0, Mode: fuse.S_IFDIR, } r[1] = fuse.DirEntry{ Name: "fs", Ino: 1, Mode: fuse.S_IFDIR, } return fs.NewListDirStream(r), 0 case 1: // info folder r := make([]fuse.DirEntry, 6) for ind, value := range properties { r[ind] = fuse.DirEntry{ Name: value.name, Ino: value.Ino, Mode: fuse.S_IFREG, } } return fs.NewListDirStream(r), 0 case 2: // on info files, err := myfs.ReadDir(n.path) if err != nil { log.Error("FUSE ReadDir failed").Str("path", n.path).Err(err).Send() return nil, syscallErr(err) } log.Debug("FUSE ReadDir succeeded").Str("path", n.path).Int("objects", len(files)).Send() r := make([]fuse.DirEntry, len(files)) n.lst = make([]DirEntry, len(files)) for ind, entry := range files { info, err := entry.Info() if err != nil { log.Error("FUSE Info failed").Str("path", n.path).Err(err).Send() return nil, syscallErr(err) } name := info.Name() file := DirEntry{ path: n.path + "/" + name, size: uint32(info.Size()), modtime: uint64(info.ModTime().Unix()), isDir: info.IsDir(), } n.lst[ind] = file ino := inodemap[file.path] if ino == 0 { ino = uint64(len(inodemap)) + 1 inodemap[file.path] = ino } if file.isDir { r[ind] = fuse.DirEntry{ Name: name, Mode: fuse.S_IFDIR, Ino: ino + 10, } } else { r[ind] = fuse.DirEntry{ Name: name, Mode: fuse.S_IFREG, Ino: ino + 10, } } } return fs.NewListDirStream(r), 0 } r := make([]fuse.DirEntry, 0) return fs.NewListDirStream(r), 0 } var _ fs.NodeLookuper = (*ITNode)(nil) func (n *ITNode) Lookup(ctx context.Context, name string, out *fuse.EntryOut) (*fs.Inode, syscall.Errno) { switch n.kind { case 0: // root folder if name == "info" { stable := fs.StableAttr{ Mode: fuse.S_IFDIR, Ino: uint64(0), } operations := &ITNode{kind: 1, Ino: 0} child := n.NewInode(ctx, operations, stable) return child, 0 } else if name == "fs" { stable := fs.StableAttr{ Mode: fuse.S_IFDIR, Ino: uint64(1), } operations := &ITNode{kind: 2, Ino: 1, path: ""} child := n.NewInode(ctx, operations, stable) return child, 0 } case 1: // info folder for _, value := range properties { if value.name == name { stable := fs.StableAttr{ Mode: fuse.S_IFREG, Ino: uint64(value.Ino), } operations := &ITNode{kind: 3, Ino: value.Ino} child := n.NewInode(ctx, operations, stable) return child, 0 } } case 2: // FS object if len(n.lst) == 0 { n.Readdir(ctx) } for _, file := range n.lst { if file.path != n.path+"/"+name { continue } log.Debug("FUSE Lookup successful").Str("path", file.path).Send() if file.isDir { stable := fs.StableAttr{ Mode: fuse.S_IFDIR, Ino: inodemap[file.path], } operations := &ITNode{kind: 2, path: file.path} child := n.NewInode(ctx, operations, stable) return child, 0 } else { stable := fs.StableAttr{ Mode: fuse.S_IFREG, Ino: inodemap[file.path], } operations := &ITNode{ kind: 2, path: file.path, self: file, } child := n.NewInode(ctx, operations, stable) return child, 0 } break } log.Warn("FUSE Lookup failed").Str("path", n.path+"/"+name).Send() } return nil, syscall.ENOENT } type bytesFileReadHandle struct { content []byte } var _ fs.FileReader = (*bytesFileReadHandle)(nil) func (fh *bytesFileReadHandle) Read(ctx context.Context, dest []byte, off int64) (fuse.ReadResult, syscall.Errno) { log.Debug("FUSE Executing Read").Int("size", len(fh.content)).Send() end := off + int64(len(dest)) if end > int64(len(fh.content)) { end = int64(len(fh.content)) } return fuse.ReadResultData(fh.content[off:end]), 0 } type sensorFileReadHandle struct { content []byte } var _ fs.FileReader = (*sensorFileReadHandle)(nil) func (fh *sensorFileReadHandle) Read(ctx context.Context, dest []byte, off int64) (fuse.ReadResult, syscall.Errno) { log.Info("Executing Read").Int("size", len(fh.content)).Send() end := off + int64(len(dest)) if end > int64(len(fh.content)) { end = int64(len(fh.content)) } return fuse.ReadResultData(fh.content[off:end]), 0 } var _ fs.FileFlusher = (*sensorFileReadHandle)(nil) func (fh *sensorFileReadHandle) Flush(ctx context.Context) (errno syscall.Errno) { return 0 } type bytesFileWriteHandle struct { content []byte path string } var _ fs.FileWriter = (*bytesFileWriteHandle)(nil) func (fh *bytesFileWriteHandle) Write(ctx context.Context, data []byte, off int64) (written uint32, errno syscall.Errno) { log.Info("Executing Write").Str("path", fh.path).Int("prev_size", len(fh.content)).Int("next_size", len(data)).Send() if off != int64(len(fh.content)) { log.Error("FUSE Write file size changed unexpectedly").Int("expect", int(off)).Int("received", len(fh.content)).Send() return 0, syscall.ENXIO } fh.content = append(fh.content[:], data[:]...) return uint32(len(data)), 0 } var _ fs.FileFlusher = (*bytesFileWriteHandle)(nil) func (fh *bytesFileWriteHandle) Flush(ctx context.Context) (errno syscall.Errno) { log.Debug("FUSE Attempting flush").Str("path", fh.path).Send() fp, err := myfs.Create(fh.path, uint32(len(fh.content))) if err != nil { log.Error("FUSE Flush failed: create").Str("path", fh.path).Err(err).Send() return syscallErr(err) } if len(fh.content) == 0 { log.Debug("FUSE Flush no data to write").Str("path", fh.path).Send() err = fp.Close() if err != nil { log.Error("FUSE Flush failed during close").Str("path", fh.path).Err(err).Send() return syscallErr(err) } return 0 } go func() { // For every progress event for sent := range fp.Progress() { log.Debug("FUSE Flush progress").Int("bytes", int(sent)).Int("total", len(fh.content)).Send() } }() r := bytes.NewReader(fh.content) nread, err := io.Copy(fp, r) if err != nil { log.Error("FUSE Flush failed during write").Str("path", fh.path).Err(err).Send() fp.Close() return syscallErr(err) } if int(nread) != len(fh.content) { log.Error("FUSE Flush failed during write").Str("path", fh.path).Int("expect", len(fh.content)).Int("got", int(nread)).Send() fp.Close() return syscall.EIO } err = fp.Close() if err != nil { log.Error("FUSE Flush failed during close").Str("path", fh.path).Err(err).Send() return syscallErr(err) } log.Debug("FUSE Flush done").Str("path", fh.path).Int("size", len(fh.content)).Send() return 0 } var _ fs.FileFsyncer = (*bytesFileWriteHandle)(nil) func (fh *bytesFileWriteHandle) Fsync(ctx context.Context, flags uint32) (errno syscall.Errno) { return fh.Flush(ctx) } var _ fs.NodeGetattrer = (*ITNode)(nil) func (bn *ITNode) Getattr(ctx context.Context, f fs.FileHandle, out *fuse.AttrOut) syscall.Errno { log.Debug("FUSE getattr").Str("path", bn.path).Send() out.Ino = bn.Ino out.Mtime = bn.self.modtime out.Ctime = bn.self.modtime out.Atime = bn.self.modtime out.Size = uint64(bn.self.size) return 0 } var _ fs.NodeSetattrer = (*ITNode)(nil) func (bn *ITNode) Setattr(ctx context.Context, fh fs.FileHandle, in *fuse.SetAttrIn, out *fuse.AttrOut) syscall.Errno { log.Debug("FUSE setattr").Str("path", bn.path).Send() out.Size = 0 out.Mtime = 0 return 0 } var _ fs.NodeOpener = (*ITNode)(nil) func (f *ITNode) Open(ctx context.Context, openFlags uint32) (fh fs.FileHandle, fuseFlags uint32, errno syscall.Errno) { switch f.kind { case 2: // FS file if openFlags&syscall.O_RDWR != 0 { log.Error("FUSE Open failed: RDWR").Str("path", f.path).Send() return nil, 0, syscall.EROFS } if openFlags&syscall.O_WRONLY != 0 { log.Debug("FUSE Opening for write").Str("path", f.path).Send() fh = &bytesFileWriteHandle{ path: f.path, content: make([]byte, 0), } return fh, fuse.FOPEN_DIRECT_IO, 0 } else { log.Debug("FUSE Opening for read").Str("path", f.path).Send() fp, err := myfs.Open(f.path) if err != nil { log.Error("FUSE: Opening failed").Str("path", f.path).Err(err).Send() return nil, 0, syscallErr(err) } defer fp.Close() b := &bytes.Buffer{} go func() { // For every progress event for sent := range fp.Progress() { log.Debug("FUSE Read progress").Int("bytes", int(sent)).Int("total", int(f.self.size)).Send() } }() _, err = io.Copy(b, fp) if err != nil { log.Error("FUSE Read failed").Str("path", f.path).Err(err).Send() fp.Close() return nil, 0, syscallErr(err) } fh = &bytesFileReadHandle{ content: b.Bytes(), } return fh, fuse.FOPEN_DIRECT_IO, 0 } case 3: // Device file // disallow writes if openFlags&(syscall.O_RDWR|syscall.O_WRONLY) != 0 { return nil, 0, syscall.EROFS } for _, value := range properties { if value.Ino == f.Ino { ans, err := value.gen() if err != nil { return nil, 0, syscallErr(err) } fh = &sensorFileReadHandle{ content: ans, } return fh, fuse.FOPEN_DIRECT_IO, 0 } } } return nil, 0, syscall.EINVAL } var _ fs.NodeCreater = (*ITNode)(nil) func (f *ITNode) Create(ctx context.Context, name string, flags uint32, mode uint32, out *fuse.EntryOut) (node *fs.Inode, fh fs.FileHandle, fuseFlags uint32, errno syscall.Errno) { if f.kind != 2 { return nil, nil, 0, syscall.EROFS } path := f.path + "/" + name ino := uint64(len(inodemap)) + 11 inodemap[path] = ino stable := fs.StableAttr{ Mode: fuse.S_IFREG, Ino: ino, } operations := &ITNode{ kind: 2, Ino: ino, path: path, } node = f.NewInode(ctx, operations, stable) fh = &bytesFileWriteHandle{ path: path, content: make([]byte, 0), } log.Debug("FUSE Creating file").Str("path", path).Send() errno = 0 return node, fh, fuseFlags, 0 } var _ fs.NodeMkdirer = (*ITNode)(nil) func (f *ITNode) Mkdir(ctx context.Context, name string, mode uint32, out *fuse.EntryOut) (*fs.Inode, syscall.Errno) { if f.kind != 2 { return nil, syscall.EROFS } path := f.path + "/" + name err := myfs.Mkdir(path) if err != nil { log.Error("FUSE Mkdir failed"). Str("path", path). Err(err). Send() return nil, syscallErr(err) } ino := uint64(len(inodemap)) + 11 inodemap[path] = ino stable := fs.StableAttr{ Mode: fuse.S_IFDIR, Ino: ino, } operations := &ITNode{ kind: 2, Ino: ino, path: path, } node := f.NewInode(ctx, operations, stable) log.Debug("FUSE Mkdir success"). Str("path", path). Int("ino", int(ino)). Send() return node, 0 } var _ fs.NodeRenamer = (*ITNode)(nil) func (f *ITNode) Rename(ctx context.Context, name string, newParent fs.InodeEmbedder, newName string, flags uint32) syscall.Errno { if f.kind != 2 { return syscall.EROFS } p1 := f.path + "/" + name p2 := newParent.EmbeddedInode().Path(nil)[2:] + "/" + newName err := myfs.Rename(p1, p2) if err != nil { log.Error("FUSE Rename failed"). Str("src", p1). Str("dest", p2). Err(err). Send() return syscallErr(err) } log.Debug("FUSE Rename sucess"). Str("src", p1). Str("dest", p2). Send() ino := inodemap[p1] delete(inodemap, p1) inodemap[p2] = ino return 0 } var _ fs.NodeUnlinker = (*ITNode)(nil) func (f *ITNode) Unlink(ctx context.Context, name string) syscall.Errno { if f.kind != 2 { return syscall.EROFS } delete(inodemap, f.path+"/"+name) err := myfs.Remove(f.path + "/" + name) if err != nil { log.Error("FUSE Unlink failed"). Str("file", f.path+"/"+name). Err(err). Send() return syscallErr(err) } log.Debug("FUSE Unlink success"). Str("file", f.path+"/"+name). Send() return 0 } var _ fs.NodeRmdirer = (*ITNode)(nil) func (f *ITNode) Rmdir(ctx context.Context, name string) syscall.Errno { return f.Unlink(ctx, name) }