Awesome

ExFat

Requirements

Node.js v10+, or equivalent runtime (Browsers work too) with BigInt support

Install via npm

$ npm install --save exfat

Supported Operations / Features

• File system creation (mkfs)
• Integrity verification & repair (aka CHKDSK)

• access( path[, mode], callback )
• appendFile( path, data[, options], callback )
• chmod( path, mode, callback )
• chown( path, uid, gid, callback )
• close( fd, callback )
• copyFile( src, dest[, flags], callback )
• createReadStream( path[, options] )
• createWriteStream( path[, options] )
• fchmod( fd, mode, callback )
• fchown( fd, uid, gid, callback )
• fdatasync( fd, callback )
• fstat( fd[, options], callback )
• fsync( fd, callback )
• ftruncate( fd[, len], callback )
• futimes( fd, atime, mtime, callback )
• lchmod( path, mode, callback )
• lchown( path, uid, gid, callback )
• link( existingPath, newPath, callback )
• lstat( path[, options], callback )
• mkdir( path[, options], callback )
• mkdtemp( prefix[, options], callback )
• open( path[, flags[, mode]], callback )
• read( fd, buffer, offset, length, position, callback )
• read( fd, [options,] callback )
• readdir( path[, options], callback )
• readFile( path[, options], callback )
• readlink( path[, options], callback )
• realpath( path[, options], callback )
• rename( oldPath, newPath, callback )
• rmdir( path[, options], callback )
• stat( path[, options], callback )
• symlink( target, path[, type], callback )
• truncate( path[, len], callback )
• unlink( path, callback )
• utimes( path, atime, mtime, callback )
• unwatchFile( filename[, listener] )
• watchFile( filename[, options], listener )
• write( fd, buffer[, offset[, length[, position]]], callback )
• write( fd, string[, position[, encoding]], callback )
• writeFile( file, data[, options], callback )
• writev( fd, buffers[, position], callback )

Usage

var ExFAT = require( 'exfat' )

To operate an ExFAT volume, a device with the below API is required. Position 0 must be the start of the ExFAT partition.

var device = {
  read( buffer, offset, length, position, callback ) {}
  write( buffer, offset, length, position, callback ) {}
}

Now a volume can be instantiated on the device:

var volume = new ExFAT.Volume({
  // Whether the volume is treated as read-only (default: true)
  readOnly: true,
  // Device's logical block size (default: device.blockSize || 512 )
  blockSize: 512,
  // I/O device API (see above)
  device: device,
})

And now the volume can be mounted and subsequently used until unmounted: NOTE: Error handling omitted for brevity.

volume.mount(( error ) => {
  
  console.log( 'Volume cluster usage', volume.fat.getUsage() )
  // -> { total: 3932160, used: 266625, bad: 0, free: 3665535 }
  console.log( 'Volume root cluster chain', volume.fat.getClusterChain( volume.vbr.rootDirCluster ) )
  // -> [ { number: 7, next: 4294967295 } ]
  
  volume.readDirEntries( this.vbr.rootDirCluster, ( error, entries ) => {
    console.log( 'Volume root directory entries:', entries )
    // -> [
    //   Label { type: 131, length: 7, value: 'WD Blue' },
    //   Bitmap {
    //     type: 129,
    //     unknown1: <Buffer 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00>,
    //     cluster: 2,
    //     size: 476723n
    //   },
    //   UpCase {
    //     type: 130,
    //     reserved1: <Buffer 00 00 00>,
    //     checksum: 3860452109,
    //     reserved2: <Buffer 00 00 00 00 00 00 00 00 00 00 00 00>,
    //     cluster: 6,
    //     size: 5836n
    //   },
    //   File {
    //     type: 133,
    //     continuations: 2,
    //     checksum: 63169,
    //     attr: 50,
    //     unknown1: 0,
    //     crtime: 21126,
    //     crdate: 20245,
    //     mtime: 21126,
    //     mdate: 20245,
    //     atime: 21126,
    //     adate: 20245,
    //     crtimeCs: 169,
    //     mtimeCs: 169,
    //     unknown2: <Buffer f8 f8 f8 00 00 00 00 00 00 00>
    //   },
    //   ...
    // ]
  })
  
  volume.unmount(( error ) => {
    // ...
  })
  
})

Examples

Inspecting Real Storage Devices

Windows:

NOTE: You'll need to run this in an Administrator command prompt

node example/inspect.js \\.\PhysicalDrive1

Mac OS:

sudo node example/inspect.js /dev/rdisk2

Linux:

sudo node example/inspect.js /dev/sda