rclone/cmd/mount/file.go
Nick Craig-Wood fc32fee4ad mount, cmount: add --attr-timeout to control attribute caching in kernel
This flag allows the attribute caching in the kernel to be controlled.
The default is 0s - no caching - which is recommended for filesystems
which can change outside the control of the kernel.

Previously this was at the default meaning it was 60s for mount and 1s
for cmount.  This showed strange effects when files changed on the
remote not via the kernel.  For instance Caddy would serve corrupted
files for a while when serving from an rclone mount when a file
changed on the remote.
2018-03-04 11:20:22 +00:00

98 lines
2.4 KiB
Go

// +build linux darwin freebsd
package mount
import (
"os"
"time"
"bazil.org/fuse"
fusefs "bazil.org/fuse/fs"
"github.com/ncw/rclone/cmd/mountlib"
"github.com/ncw/rclone/fs/log"
"github.com/ncw/rclone/vfs"
"golang.org/x/net/context"
)
// File represents a file
type File struct {
*vfs.File
}
// Check interface satisfied
var _ fusefs.Node = (*File)(nil)
// Attr fills out the attributes for the file
func (f *File) Attr(ctx context.Context, a *fuse.Attr) (err error) {
defer log.Trace(f, "")("a=%+v, err=%v", a, &err)
a.Valid = mountlib.AttrTimeout
modTime := f.File.ModTime()
Size := uint64(f.File.Size())
Blocks := (Size + 511) / 512
a.Gid = f.VFS().Opt.GID
a.Uid = f.VFS().Opt.UID
a.Mode = f.VFS().Opt.FilePerms
a.Size = Size
a.Atime = modTime
a.Mtime = modTime
a.Ctime = modTime
a.Crtime = modTime
a.Blocks = Blocks
return nil
}
// Check interface satisfied
var _ fusefs.NodeSetattrer = (*File)(nil)
// Setattr handles attribute changes from FUSE. Currently supports ModTime and Size only
func (f *File) Setattr(ctx context.Context, req *fuse.SetattrRequest, resp *fuse.SetattrResponse) (err error) {
defer log.Trace(f, "a=%+v", req)("err=%v", &err)
if !f.VFS().Opt.NoModTime {
if req.Valid.Mtime() {
err = f.File.SetModTime(req.Mtime)
} else if req.Valid.MtimeNow() {
err = f.File.SetModTime(time.Now())
}
}
if req.Valid.Size() {
err = f.File.Truncate(int64(req.Size))
}
return translateError(err)
}
// Check interface satisfied
var _ fusefs.NodeOpener = (*File)(nil)
// Open the file for read or write
func (f *File) Open(ctx context.Context, req *fuse.OpenRequest, resp *fuse.OpenResponse) (fh fusefs.Handle, err error) {
defer log.Trace(f, "flags=%v", req.Flags)("fh=%v, err=%v", &fh, &err)
// fuse flags are based off syscall flags as are os flags, so
// should be compatible
//
// we seem to be missing O_CREATE here so add it in to allow
// file creation
handle, err := f.File.Open(int(req.Flags) | os.O_CREATE)
if err != nil {
return nil, translateError(err)
}
// See if seeking is supported and set FUSE hint accordingly
if _, err = handle.Seek(0, 1); err != nil {
resp.Flags |= fuse.OpenNonSeekable
}
return &FileHandle{handle}, nil
}
// Check interface satisfied
var _ fusefs.NodeFsyncer = (*File)(nil)
// Fsync the file
//
// Note that we don't do anything except return OK
func (f *File) Fsync(ctx context.Context, req *fuse.FsyncRequest) (err error) {
defer log.Trace(f, "")("err=%v", &err)
return nil
}