File format you get when creating an alias in Finder

macos_bookmark_file.ksy

meta:
  id: macos_bookmark_file
  endian: le
  #file-extension: macos-bookmark-file

seq:
  - id: header
    type: header
  - id: toc_offset
    type: u4

types:

  header:
    seq:
      - id: magic
        size: 4
        type: str
        encoding: US-ASCII
        valid: "'book'"
      - id: reserved1
        size: 4
      - id: magic2
        size: 4
        type: str
        encoding: US-ASCII
        valid: "'mark'"
      - id: reserved2
        size: 4
      - id: header_len
        type: u4
      - id: header_len_2
        type: u4
      - id: unknown1
        size: 16
      - id: unknown2_maybe_timestamp
        size: 8
      - id: unknown_remainder
        size: header_len - 48

  toc_section:
    seq:
      - id: len
        type: u4
      - id: magic
        type: u4
        valid: '0xFFFFFFFE'
      - id: tocs
        type: toc
        repeat: expr
        repeat-expr: 1

  toc:
    seq:
      - id: toc_id
        type: u4
      - id: unknown4
        type: u4
      - id: entry_count
        type: u4
      - id: toc_entries
        type: toc_entry
        repeat: expr
        repeat-expr: entry_count

  toc_entry:
    seq:
      - id: property_id
        type: u4
      - id: value
        type: typed_value_ref
      - id: unknown3
        type: u4
    -webide-representation: '{property_id} = {value}'

  typed_value:
    seq:
    - id: length
      type: u4
    - id: value_type
      type: u4
      enum: type
    - id: value
      size: length
      type:
        switch-on: value_type
        cases:
          'type::string': typed_value_string
          'type::data': typed_value_data
          'type::number_u1': u1
          'type::number_u2': u2
          'type::number_u4': u4
          'type::number_u8': u8
          'type::number_f4': f4
          'type::number_f8': f8
          'type::date': typed_value_date
          'type::boolean_false': typed_value_boolean_false
          'type::boolean_true': typed_value_boolean_true
          'type::array': typed_value_array
          'type::url_absolute': typed_value_url_absolute
          'type::url_relative': typed_value_url_relative
          'type::null_value': typed_value_null
          _: typed_value_unknown
    - id: padding
      if: length % 4 != 0
      size: 4 - length % 4
    -webide-representation: '{value}'

  typed_value_ref:
    seq:
    - id: offset
      type: u4
    instances:
      actual_offset:
        value: offset + _root.header.header_len
      value:
        pos: actual_offset
        type: typed_value
        io: _root._io
        -webide-parse-mode: eager
    -webide-representation: '{value}'

  typed_value_unknown:
    seq:
    - id: value
      size-eos: true
    -webide-representation: 'UNKNOWN({value})'

  typed_value_data:
    seq:
    - id: value
      size-eos: true
    -webide-representation: '{value}'

  typed_value_string:
    seq:
    - id: value
      size-eos: true
      type: str
      encoding: UTF-8
    -webide-representation: '{value}'

  typed_value_date:
    seq:
    - id: seconds
      type: f8be
    -webide-representation: '{seconds} seconds since Jan 1 2001'

  typed_value_array:
    seq:
    - id: entry_offsets
      type: typed_value_ref
      repeat: eos
    -webide-representation: '{entry_offsets}'

  typed_value_boolean_true:
    instances:
      value:
        value: true
    -webide-representation: '{value}'

  typed_value_boolean_false:
    instances:
      value:
        value: false
    -webide-representation: '{value}'

  typed_value_url_absolute:
    seq:
    - id: value
      size-eos: true
      type: str
      encoding: UTF-8
    -webide-representation: '{value}'

  typed_value_url_relative:
    seq:
    - id: base
      type: typed_value_ref
    - id: relative
      type: typed_value_ref
    -webide-representation: '{base}/{relative}'

  typed_value_null:
    -webide-representation: 'null'

instances:

  toc:
    pos: _root.toc_offset + _root.header.header_len
    type: toc_section

enums:
  type:
    0x101: string
    0x201: data
    0x301: number_u1
    0x302: number_u2
    0x303: number_u4
    0x304: number_u8
    0x305: number_f4
    0x306: number_f8
    0x400: date
    0x500: boolean_false
    0x501: boolean_true
    0x601: array
    0x701: dictionary
    0x801: uuid
    0x901: url_absolute
    0x902: url_relative
    0xA00: null_value