package command import ( "bufio" "fmt" "io" "os" "strings" "github.com/seaweedfs/fuse" ) const ( /* 36 35 98:0 /mnt1 /mnt2 rw,noatime master:1 - ext3 /dev/root rw,errors=continue (1)(2)(3) (4) (5) (6) (7) (8) (9) (10) (11) (1) mount ID: unique identifier of the mount (may be reused after umount) (2) parent ID: ID of parent (or of self for the top of the mount tree) (3) major:minor: value of st_dev for files on filesystem (4) root: root of the mount within the filesystem (5) mount point: mount point relative to the process's root (6) mount options: per mount options (7) optional fields: zero or more fields of the form "tag[:value]" (8) separator: marks the end of the optional fields (9) filesystem type: name of filesystem of the form "type[.subtype]" (10) mount source: filesystem specific information or "none" (11) super options: per super block options*/ mountinfoFormat = "%d %d %d:%d %s %s %s %s" ) // Info reveals information about a particular mounted filesystem. This // struct is populated from the content in the /proc//mountinfo file. type Info struct { // ID is a unique identifier of the mount (may be reused after umount). ID int // Parent indicates the ID of the mount parent (or of self for the top of the // mount tree). Parent int // Major indicates one half of the device ID which identifies the device class. Major int // Minor indicates one half of the device ID which identifies a specific // instance of device. Minor int // Root of the mount within the filesystem. Root string // Mountpoint indicates the mount point relative to the process's root. Mountpoint string // Opts represents mount-specific options. Opts string // Optional represents optional fields. Optional string // Fstype indicates the type of filesystem, such as EXT3. Fstype string // Source indicates filesystem specific information or "none". Source string // VfsOpts represents per super block options. VfsOpts string } // Mounted determines if a specified mountpoint has been mounted. // On Linux it looks at /proc/self/mountinfo and on Solaris at mnttab. func mounted(mountPoint string) (bool, error) { entries, err := parseMountTable() if err != nil { return false, err } // Search the table for the mountPoint for _, e := range entries { if e.Mountpoint == mountPoint { return true, nil } } return false, nil } // Parse /proc/self/mountinfo because comparing Dev and ino does not work from // bind mounts func parseMountTable() ([]*Info, error) { f, err := os.Open("/proc/self/mountinfo") if err != nil { return nil, err } defer f.Close() return parseInfoFile(f) } func parseInfoFile(r io.Reader) ([]*Info, error) { var ( s = bufio.NewScanner(r) out []*Info ) for s.Scan() { if err := s.Err(); err != nil { return nil, err } var ( p = &Info{} text = s.Text() optionalFields string ) if _, err := fmt.Sscanf(text, mountinfoFormat, &p.ID, &p.Parent, &p.Major, &p.Minor, &p.Root, &p.Mountpoint, &p.Opts, &optionalFields); err != nil { return nil, fmt.Errorf("Scanning '%s' failed: %s", text, err) } // Safe as mountinfo encodes mountpoints with spaces as \040. index := strings.Index(text, " - ") postSeparatorFields := strings.Fields(text[index+3:]) if len(postSeparatorFields) < 3 { return nil, fmt.Errorf("Error found less than 3 fields post '-' in %q", text) } if optionalFields != "-" { p.Optional = optionalFields } p.Fstype = postSeparatorFields[0] p.Source = postSeparatorFields[1] p.VfsOpts = strings.Join(postSeparatorFields[2:], " ") out = append(out, p) } return out, nil } func osSpecificMountOptions() []fuse.MountOption { return []fuse.MountOption{} } func checkMountPointAvailable(dir string) bool { mountPoint := dir if mountPoint != "/" && strings.HasSuffix(mountPoint, "/") { mountPoint = mountPoint[0 : len(mountPoint)-1] } if mounted, err := mounted(mountPoint); err != nil || mounted { return false } return true }