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serve.go
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serve.go
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// FUSE service loop, for servers that wish to use it.
package fs
import (
"encoding/binary"
"fmt"
"hash/fnv"
"io"
"log"
"reflect"
"runtime"
"strings"
"sync"
"time"
"context"
)
import (
"github.com/ipfs/go-ipfs/Godeps/_workspace/src/bazil.org/fuse"
"github.com/ipfs/go-ipfs/Godeps/_workspace/src/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 FSIniter.
type FS interface {
// Root is called to obtain the Node for the file system root.
Root() (Node, error)
}
type FSIniter interface {
// Init is called to initialize the FUSE connection.
// It can inspect the request and adjust the response as desired.
// Init must return promptly.
Init(ctx context.Context, req *fuse.InitRequest, resp *fuse.InitResponse) 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.
//
// Other FUSE requests can be handled by implementing methods from the
// Node* interfaces, for example NodeOpener.
type Node interface {
// Attr fills attr with the standard metadata for the node.
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. Not implementing Setattr causes writes to be unable
// to grow the file (except with OpenDirectIO, which bypasses that
// mechanism).
//
// 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 nil, err.
//
// 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.
//
// 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.
//
// Note that file size changes are communicated through Setattr.
// Writes beyond the size of the file as reported by Attr are not
// even attempted (except in OpenDirectIO mode).
Write(ctx context.Context, req *fuse.WriteRequest, resp *fuse.WriteResponse) error
}
type HandleReleaser interface {
Release(ctx context.Context, req *fuse.ReleaseRequest) error
}
type Server struct {
FS FS
// 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{})
// 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(c *fuse.Conn) error {
defer s.wg.Wait() // Wait for worker goroutines to complete before return
sc := serveConn{
fs: s.FS,
debug: s.Debug,
req: map[fuse.RequestID]*serveRequest{},
dynamicInode: GenerateDynamicInode,
}
if sc.debug == nil {
sc.debug = fuse.Debug
}
if dyn, ok := sc.fs.(FSInodeGenerator); ok {
sc.dynamicInode = dyn.GenerateInode
}
root, err := sc.fs.Root()
if err != nil {
return fmt.Errorf("cannot obtain root node: %v", err)
}
sc.node = append(sc.node, nil, &serveNode{inode: 1, node: root, refs: 1})
sc.handle = append(sc.handle, nil)
for {
req, err := c.ReadRequest()
if err != nil {
if err == io.EOF {
break
}
return err
}
s.wg.Add(1)
go func() {
defer s.wg.Done()
sc.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 := Server{
FS: fs,
}
return server.Serve(c)
}
type nothing struct{}
type serveConn struct {
meta sync.Mutex
fs FS
req map[fuse.RequestID]*serveRequest
node []*serveNode
handle []*serveHandle
freeNode []fuse.NodeID
freeHandle []fuse.HandleID
nodeGen uint64
debug func(msg interface{})
dynamicInode func(parent uint64, name string) uint64
}
type serveRequest struct {
Request fuse.Request
cancel func()
}
type serveNode struct {
inode uint64
node Node
refs uint64
}
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 can be embedded in a Node to recognize the same Node being
// returned from multiple Lookup, Create etc calls.
//
// 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 NodeRef struct {
id fuse.NodeID
generation uint64
}
// nodeRef is only ever accessed while holding serveConn.meta
func (n *NodeRef) nodeRef() *NodeRef {
return n
}
type nodeRef interface {
nodeRef() *NodeRef
}
func (c *serveConn) saveNode(inode uint64, node Node) (id fuse.NodeID, gen uint64) {
c.meta.Lock()
defer c.meta.Unlock()
var ref *NodeRef
if nodeRef, ok := node.(nodeRef); ok {
ref = nodeRef.nodeRef()
if ref.id != 0 {
// dropNode guarantees that NodeRef is zeroed at the same
// time as the NodeID is removed from serveConn.node, as
// guarded by c.meta; this means sn cannot be nil here
sn := c.node[ref.id]
sn.refs++
return ref.id, ref.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)
}
gen = c.nodeGen
if ref != nil {
ref.id = id
ref.generation = gen
}
return
}
func (c *serveConn) 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 *serveConn) 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 {
c.node[id] = nil
if nodeRef, ok := snode.node.(nodeRef); ok {
ref := nodeRef.nodeRef()
*ref = NodeRef{}
}
c.freeNode = append(c.freeNode, id)
return true
}
return false
}
func (c *serveConn) 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 *serveConn) 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=%#x", 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("-> %s error=%s %s", r.Request, r.errstr(), r.Out)
case r.Errno != "":
return fmt.Sprintf("-> %s error=%s", r.Request, r.errstr())
case r.Out != nil:
// make sure (seemingly) empty values are readable
switch r.Out.(type) {
case string:
return fmt.Sprintf("-> %s %q", r.Request, r.Out)
case []byte:
return fmt.Sprintf("-> %s [% x]", r.Request, r.Out)
default:
return fmt.Sprintf("-> %s %s", r.Request, r.Out)
}
default:
return fmt.Sprintf("-> %s", r.Request)
}
}
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 %#x), 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 %#x), 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
}
func initLookupResponse(s *fuse.LookupResponse) {
s.EntryValid = entryValidTime
}
func (c *serveConn) serve(r fuse.Request) {
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
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()
}
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)
}
}()
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.
done(fuse.ENOSYS)
r.RespondError(fuse.ENOSYS)
// FS operations.
case *fuse.InitRequest:
s := &fuse.InitResponse{
MaxWrite: 128 * 1024,
Flags: fuse.InitBigWrites,
}
if fs, ok := c.fs.(FSIniter); ok {
if err := fs.Init(ctx, r, s); err != nil {
done(err)
r.RespondError(err)
break
}
}
done(s)
r.Respond(s)
case *fuse.StatfsRequest:
s := &fuse.StatfsResponse{}
if fs, ok := c.fs.(FSStatfser); ok {
if err := fs.Statfs(ctx, r, s); err != nil {
done(err)
r.RespondError(err)
break
}
}
done(s)
r.Respond(s)
// Node operations.
case *fuse.GetattrRequest:
s := &fuse.GetattrResponse{}
if n, ok := node.(NodeGetattrer); ok {
if err := n.Getattr(ctx, r, s); err != nil {
done(err)
r.RespondError(err)
break
}
} else {
if err := snode.attr(ctx, &s.Attr); err != nil {
done(err)
r.RespondError(err)
break
}
}
done(s)
r.Respond(s)
case *fuse.SetattrRequest:
s := &fuse.SetattrResponse{}
if n, ok := node.(NodeSetattrer); ok {
if err := n.Setattr(ctx, r, s); err != nil {
done(err)
r.RespondError(err)
break
}
done(s)
r.Respond(s)
break
}
if err := snode.attr(ctx, &s.Attr); err != nil {
done(err)
r.RespondError(err)
break
}
done(s)
r.Respond(s)
case *fuse.SymlinkRequest:
s := &fuse.SymlinkResponse{}
initLookupResponse(&s.LookupResponse)
n, ok := node.(NodeSymlinker)
if !ok {
done(fuse.EIO) // XXX or EPERM like Mkdir?
r.RespondError(fuse.EIO)
break
}
n2, err := n.Symlink(ctx, r)
if err != nil {
done(err)
r.RespondError(err)
break
}
if err := c.saveLookup(ctx, &s.LookupResponse, snode, r.NewName, n2); err != nil {
done(err)
r.RespondError(err)
break
}
done(s)
r.Respond(s)
case *fuse.ReadlinkRequest:
n, ok := node.(NodeReadlinker)
if !ok {
done(fuse.EIO) /// XXX or EPERM?
r.RespondError(fuse.EIO)
break
}
target, err := n.Readlink(ctx, r)
if err != nil {
done(err)
r.RespondError(err)
break
}
done(target)
r.Respond(target)
case *fuse.LinkRequest:
n, ok := node.(NodeLinker)
if !ok {
done(fuse.EIO) /// XXX or EPERM?
r.RespondError(fuse.EIO)
break
}
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,
})
done(fuse.EIO)
r.RespondError(fuse.EIO)
break
}
n2, err := n.Link(ctx, r, oldNode.node)
if err != nil {
done(err)
r.RespondError(err)
break
}
s := &fuse.LookupResponse{}
initLookupResponse(s)
if err := c.saveLookup(ctx, s, snode, r.NewName, n2); err != nil {
done(err)
r.RespondError(err)
break
}
done(s)
r.Respond(s)
case *fuse.RemoveRequest:
n, ok := node.(NodeRemover)
if !ok {
done(fuse.EIO) /// XXX or EPERM?
r.RespondError(fuse.EIO)
break
}
err := n.Remove(ctx, r)
if err != nil {
done(err)
r.RespondError(err)
break
}
done(nil)
r.Respond()
case *fuse.AccessRequest:
if n, ok := node.(NodeAccesser); ok {
if err := n.Access(ctx, r); err != nil {
done(err)
r.RespondError(err)
break
}
}
done(nil)
r.Respond()
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 {
done(fuse.ENOENT)
r.RespondError(fuse.ENOENT)
break
}
if err != nil {
done(err)
r.RespondError(err)
break
}
if err := c.saveLookup(ctx, s, snode, r.Name, n2); err != nil {
done(err)
r.RespondError(err)
break
}
done(s)
r.Respond(s)
case *fuse.MkdirRequest:
s := &fuse.MkdirResponse{}
initLookupResponse(&s.LookupResponse)
n, ok := node.(NodeMkdirer)
if !ok {
done(fuse.EPERM)
r.RespondError(fuse.EPERM)
break
}
n2, err := n.Mkdir(ctx, r)
if err != nil {
done(err)
r.RespondError(err)
break
}
if err := c.saveLookup(ctx, &s.LookupResponse, snode, r.Name, n2); err != nil {
done(err)
r.RespondError(err)
break