class Minitar::PosixHeader

Implements the POSIX tar header as a Ruby class. The structure of the POSIX tar header is:

struct tarfile_entry_posix { // pack unpack char name; // ASCII (+ Z unless filled) a100 Z100 char mode; // 0 padded, octal, null a8 A8 char uid; // 0 padded, octal, null a8 A8 char gid; // 0 padded, octal, null a8 A8 char size; // 0 padded, octal, null a12 A12 char mtime; // 0 padded, octal, null a12 A12 char checksum; // 0 padded, octal, null, space a8 A8 char typeflag; // see below a a char linkname; // ASCII + (Z unless filled) a100 Z100 char magic; // “ustar0” a6 A6 char version; // “00” a2 A2 char uname; // ASCIIZ a32 Z32 char gname; // ASCIIZ a32 Z32 char devmajor; // 0 padded, octal, null a8 A8 char devminor; // 0 padded, octal, null a8 A8 char prefix; // ASCII (+ Z unless filled) a155 Z155 };

The typeflag is one of several known values. POSIX indicates that “A POSIX-compliant implementation must treat any unrecognized typeflag value as a regular file.”

Constants

BLOCK_SIZE
FIELDS: All fields available in a POSIX tar(1) header.
GNU_EXT_LONG_LINK
HEADER_PACK_FORMAT: The pack format passed to Array#pack for encoding a header.
HEADER_UNPACK_FORMAT: The unpack format passed to String#unpack for decoding a header.
MAGIC_BYTES
OPTIONAL_FIELDS: Fields that may be set in a POSIX tar(1) header.
REQUIRED_FIELDS: Fields that must be set in a POSIX tar(1) header.

Attributes

checksum [R]

The checksum of the file. Stored as an octal integer. Calculated before encoding the header as a string.

devmajor [R]

The major device ID. Not currently used.

devminor [R]

The minor device ID. Not currently used.

gid [R]

The Unix owner group ID of the file. Stored as an octal integer.

gname [R]

The group name of the Unix owner of the file.

linkname [R]

The target of the symbolic link.

magic [R]

Always “ustar0”.

mode [R]

The Unix file mode of the file. Stored as an octal integer. Required.

mtime [R]

The modification time of the file in epoch seconds. Stored as an octal integer.

name [RW]

The name of the file. Required.

By default, limited to 100 bytes, but may be up to BLOCK_SIZE bytes if using the GNU long name tar extension.

prefix [R]

The prefix of the file; the path before name. Limited to 155 bytes. Required.

size [RW]

The size of the file. Required.

typeflag [R]

The type of record in the file.

0:: Regular file. NULL should be treated as a synonym, for compatibility purposes. 1:: Hard link. 2:: Symbolic link. 3:: Character device node. 4:: Block device node. 5:: Directory. 6:: FIFO node. 7:: Reserved. L:: GNU extension for long filenames when name is ././@LongLink.

uid [R]

The Unix owner user ID of the file. Stored as an octal integer.

uname [R]

The user name of the Unix owner of the file.

version [R]

Always “00”

Public Class Methods

calculate_checksum (hdr)

Source

# File lib/minitar/posix_header.rb, line 213
def calculate_checksum(hdr)
  hdr.unpack("C*").inject(:+)
end

empty? (= @empty)

Source

# File lib/minitar/posix_header.rb, line 157
def empty? = @empty

# Indicates if the header has a valid magic value.
def valid? = empty? || @magic == MAGIC_BYTES

# Returns +true+ if the header is a long name special header which indicates
# that the next block of data is the filename.
def long_name? = typeflag == "L" && name == GNU_EXT_LONG_LINK

# Returns +true+ if the header is a PAX extended header which contains
# metadata for the next file entry.
def pax_header? = typeflag == "x"

# Sets the +name+ to the +value+ provided and clears +prefix+.
#
# Used by Minitar::Reader#each_entry to set the long name when processing GNU long
# filename extensions.
#
# The +value+ must be the complete name, including leading directory components.
def long_name=(value)
  valid_name!(value)

  @prefix = ""
  @name = value
end

# A string representation of the header.
def to_s
  update_checksum
  header(@checksum)
end
alias_method :to_str, :to_s

# TODO: In Minitar 2, PosixHeader#to_str will be removed.

# Update the checksum field.
def update_checksum
  hh = header(" " * 8)
  @checksum = oct(calculate_checksum(hh), 6)
end

private

def valid_name!(value)
  return if value.is_a?(String) && !value.empty?
  raise ArgumentError, "Field name must be a non-empty string"
end

def oct(num, len)
  if num.nil?
    "\0" * (len + 1)
  else
    "%0#{len}o" % num
  end
end

def calculate_checksum(hdr)
  hdr.unpack("C*").inject(:+)
end

def header(chksum)
  arr = [name, oct(mode, 7), oct(uid, 7), oct(gid, 7), oct(size, 11),
    oct(mtime, 11), chksum, " ", typeflag, linkname, magic, version,
    uname, gname, oct(devmajor, 7), oct(devminor, 7), prefix]
  str = arr.pack(HEADER_PACK_FORMAT)
  str + "\0" * ((BLOCK_SIZE - str.bytesize) % BLOCK_SIZE)
end

##
# :attr_accessor: name
# The name of the file. Required.
#
# By default, limited to 100 bytes, but may be up to BLOCK_SIZE bytes if using the
# GNU long name tar extension.

##
# :attr_accessor: size
# The size of the file. Required.

##
# :attr_reader: prefix
# The prefix of the file; the path before #name. Limited to 155 bytes.
# Required.

##
# :attr_reader: mode
# The Unix file mode of the file. Stored as an octal integer. Required.

##
# :attr_reader: uid
# The Unix owner user ID of the file. Stored as an octal integer.

##
# :attr_reader: uname
# The user name of the Unix owner of the file.

##
# :attr_reader: gid
# The Unix owner group ID of the file. Stored as an octal integer.

##
# :attr_reader: gname
# The group name of the Unix owner of the file.

##
# :attr_reader: mtime
# The modification time of the file in epoch seconds. Stored as an
# octal integer.

##
# :attr_reader: checksum
# The checksum of the file. Stored as an octal integer. Calculated
# before encoding the header as a string.

##
# :attr_reader: typeflag
# The type of record in the file.
#
# +0+::  Regular file. NULL should be treated as a synonym, for compatibility
#        purposes.
# +1+::  Hard link.
# +2+::  Symbolic link.
# +3+::  Character device node.
# +4+::  Block device node.
# +5+::  Directory.
# +6+::  FIFO node.
# +7+::  Reserved.
# +L+::  GNU extension for long filenames when #name is <tt>././@LongLink</tt>.

##
# :attr_reader: linkname
# The target of the symbolic link.

##
# :attr_reader: magic
# Always "ustar\0".

##
# :attr_reader: version
# Always "00"

##
# :attr_reader: devmajor
# The major device ID. Not currently used.

##
# :attr_reader: devminor
# The minor device ID. Not currently used.

Indicates if the header was an empty header.

from_data (data)

Source

# File lib/minitar/posix_header.rb, line 68
def from_data(data)
  fields = data.unpack(HEADER_UNPACK_FORMAT)
  name = fields.shift
  mode = fields.shift.oct
  uid = fields.shift.oct
  gid = fields.shift.oct
  size = parse_numeric_field(fields.shift)
  mtime = fields.shift.oct
  checksum = fields.shift.oct
  typeflag = fields.shift
  linkname = fields.shift
  magic = fields.shift
  version = fields.shift.oct
  uname = fields.shift
  gname = fields.shift
  devmajor = fields.shift.oct
  devminor = fields.shift.oct
  prefix = fields.shift

  empty = !data.each_byte.any?(&:nonzero?)

  new(
    name: name,
    mode: mode,
    uid: uid,
    gid: gid,
    size: size,
    mtime: mtime,
    checksum: checksum,
    typeflag: typeflag,
    magic: magic,
    version: version,
    uname: uname,
    gname: gname,
    devmajor: devmajor,
    devminor: devminor,
    prefix: prefix,
    empty: empty,
    linkname: linkname
  )
end

Creates a new PosixHeader from a BLOCK_SIZE-byte data buffer.

from_stream (stream)

Source

# File lib/minitar/posix_header.rb, line 65
  def from_stream(stream) = from_data(stream.read(BLOCK_SIZE))

  # Creates a new PosixHeader from a BLOCK_SIZE-byte data buffer.
  def from_data(data)
    fields = data.unpack(HEADER_UNPACK_FORMAT)
    name = fields.shift
    mode = fields.shift.oct
    uid = fields.shift.oct
    gid = fields.shift.oct
    size = parse_numeric_field(fields.shift)
    mtime = fields.shift.oct
    checksum = fields.shift.oct
    typeflag = fields.shift
    linkname = fields.shift
    magic = fields.shift
    version = fields.shift.oct
    uname = fields.shift
    gname = fields.shift
    devmajor = fields.shift.oct
    devminor = fields.shift.oct
    prefix = fields.shift

    empty = !data.each_byte.any?(&:nonzero?)

    new(
      name: name,
      mode: mode,
      uid: uid,
      gid: gid,
      size: size,
      mtime: mtime,
      checksum: checksum,
      typeflag: typeflag,
      magic: magic,
      version: version,
      uname: uname,
      gname: gname,
      devmajor: devmajor,
      devminor: devminor,
      prefix: prefix,
      empty: empty,
      linkname: linkname
    )
  end

  private

  def parse_numeric_field(string)
    return string.oct if /\A[0-7 \0]*\z/.match?(string) # \0 appears as a padding
    return parse_base256(string) if string.bytes.first == 0x80 || string.bytes.first == 0xff
    raise ArgumentError, "#{string.inspect} is not a valid numeric field"
  end

  def parse_base256(string)
    # https://www.gnu.org/software/tar/manual/html_node/Extensions.html
    bytes = string.bytes
    case bytes.first
    when 0x80 # Positive number: *non-leading* bytes, number in big-endian order
      bytes[1..].inject(0) { |r, byte| (r << 8) | byte }
    when 0xff # Negative number: *all* bytes, two's complement in big-endian order
      result = bytes.inject(0) { |r, byte| (r << 8) | byte }
      bit_length = bytes.size * 8
      result - (1 << bit_length)
    else
      raise ArgumentError, "Invalid binary field format"
    end
  end
end

Creates a new PosixHeader from a data stream.

header (chksum)

Source

# File lib/minitar/posix_header.rb, line 217
def header(chksum)
  arr = [name, oct(mode, 7), oct(uid, 7), oct(gid, 7), oct(size, 11),
    oct(mtime, 11), chksum, " ", typeflag, linkname, magic, version,
    uname, gname, oct(devmajor, 7), oct(devminor, 7), prefix]
  str = arr.pack(HEADER_PACK_FORMAT)
  str + "\0" * ((BLOCK_SIZE - str.bytesize) % BLOCK_SIZE)
end

initialize (v)

Source

# File lib/minitar/posix_header.rb, line 136
def initialize(v)
  REQUIRED_FIELDS.each do |f|
    raise ArgumentError, "Field #{f} is required." unless v.key?(f)
  end

  v[:mtime] = v[:mtime].to_i
  v[:checksum] ||= ""
  v[:typeflag] ||= "0"
  v[:magic] ||= MAGIC_BYTES
  v[:version] ||= "00"

  FIELDS.each do |f|
    instance_variable_set(:"@#{f}", v[f])
  end

  @empty = v[:empty]

  valid_name!(v[:name]) unless v[:empty]
end

Creates a new PosixHeader. A PosixHeader cannot be created unless name, size, prefix, and mode are provided.

long_name= (value)

Source

# File lib/minitar/posix_header.rb, line 176
def long_name=(value)
  valid_name!(value)

  @prefix = ""
  @name = value
end

Sets the name to the value provided and clears prefix.

Used by Minitar::Reader#each_entry to set the long name when processing GNU long filename extensions.

The value must be the complete name, including leading directory components.

long_name? (= typeflag == "L" && name == GNU_EXT_LONG_LINK)

Source

# File lib/minitar/posix_header.rb, line 164
    def long_name? = typeflag == "L" && name == GNU_EXT_LONG_LINK

    # Returns +true+ if the header is a PAX extended header which contains
    # metadata for the next file entry.
    def pax_header? = typeflag == "x"

    # Sets the +name+ to the +value+ provided and clears +prefix+.
    #
    # Used by Minitar::Reader#each_entry to set the long name when processing GNU long
    # filename extensions.
    #
    # The +value+ must be the complete name, including leading directory components.
    def long_name=(value)
      valid_name!(value)

      @prefix = ""
      @name = value
    end

    # A string representation of the header.
    def to_s
      update_checksum
      header(@checksum)
    end
    alias_method :to_str, :to_s

    # TODO: In Minitar 2, PosixHeader#to_str will be removed.

    # Update the checksum field.
    def update_checksum
      hh = header(" " * 8)
      @checksum = oct(calculate_checksum(hh), 6)
    end

    private

    def valid_name!(value)
      return if value.is_a?(String) && !value.empty?
      raise ArgumentError, "Field name must be a non-empty string"
    end

    def oct(num, len)
      if num.nil?
        "\0" * (len + 1)
      else
        "%0#{len}o" % num
      end
    end

    def calculate_checksum(hdr)
      hdr.unpack("C*").inject(:+)
    end

    def header(chksum)
      arr = [name, oct(mode, 7), oct(uid, 7), oct(gid, 7), oct(size, 11),
        oct(mtime, 11), chksum, " ", typeflag, linkname, magic, version,
        uname, gname, oct(devmajor, 7), oct(devminor, 7), prefix]
      str = arr.pack(HEADER_PACK_FORMAT)
      str + "\0" * ((BLOCK_SIZE - str.bytesize) % BLOCK_SIZE)
    end

    ##
    # :attr_accessor: name
    # The name of the file. Required.
    #
    # By default, limited to 100 bytes, but may be up to BLOCK_SIZE bytes if using the
    # GNU long name tar extension.

    ##
    # :attr_accessor: size
    # The size of the file. Required.

    ##
    # :attr_reader: prefix
    # The prefix of the file; the path before #name. Limited to 155 bytes.
    # Required.

    ##
    # :attr_reader: mode
    # The Unix file mode of the file. Stored as an octal integer. Required.

    ##
    # :attr_reader: uid
    # The Unix owner user ID of the file. Stored as an octal integer.

    ##
    # :attr_reader: uname
    # The user name of the Unix owner of the file.

    ##
    # :attr_reader: gid
    # The Unix owner group ID of the file. Stored as an octal integer.

    ##
    # :attr_reader: gname
    # The group name of the Unix owner of the file.

    ##
    # :attr_reader: mtime
    # The modification time of the file in epoch seconds. Stored as an
    # octal integer.

    ##
    # :attr_reader: checksum
    # The checksum of the file. Stored as an octal integer. Calculated
    # before encoding the header as a string.

    ##
    # :attr_reader: typeflag
    # The type of record in the file.
    #
    # +0+::  Regular file. NULL should be treated as a synonym, for compatibility
    #        purposes.
    # +1+::  Hard link.
    # +2+::  Symbolic link.
    # +3+::  Character device node.
    # +4+::  Block device node.
    # +5+::  Directory.
    # +6+::  FIFO node.
    # +7+::  Reserved.
    # +L+::  GNU extension for long filenames when #name is <tt>././@LongLink</tt>.

    ##
    # :attr_reader: linkname
    # The target of the symbolic link.

    ##
    # :attr_reader: magic
    # Always "ustar\0".

    ##
    # :attr_reader: version
    # Always "00"

    ##
    # :attr_reader: devmajor
    # The major device ID. Not currently used.

    ##
    # :attr_reader: devminor
    # The minor device ID. Not currently used.
  end
end

Returns true if the header is a long name special header which indicates that the next block of data is the filename.

oct (num, len)

Source

# File lib/minitar/posix_header.rb, line 205
def oct(num, len)
  if num.nil?
    "\0" * (len + 1)
  else
    "%0#{len}o" % num
  end
end

parse_base256 (string)

Source

# File lib/minitar/posix_header.rb, line 118
def parse_base256(string)
  # https://www.gnu.org/software/tar/manual/html_node/Extensions.html
  bytes = string.bytes
  case bytes.first
  when 0x80 # Positive number: *non-leading* bytes, number in big-endian order
    bytes[1..].inject(0) { |r, byte| (r << 8) | byte }
  when 0xff # Negative number: *all* bytes, two's complement in big-endian order
    result = bytes.inject(0) { |r, byte| (r << 8) | byte }
    bit_length = bytes.size * 8
    result - (1 << bit_length)
  else
    raise ArgumentError, "Invalid binary field format"
  end
end

parse_numeric_field (string)

Source

# File lib/minitar/posix_header.rb, line 112
def parse_numeric_field(string)
  return string.oct if /\A[0-7 \0]*\z/.match?(string) # \0 appears as a padding
  return parse_base256(string) if string.bytes.first == 0x80 || string.bytes.first == 0xff
  raise ArgumentError, "#{string.inspect} is not a valid numeric field"
end

pax_header? (= typeflag == "x")

Source

# File lib/minitar/posix_header.rb, line 168
  def pax_header? = typeflag == "x"

  # Sets the +name+ to the +value+ provided and clears +prefix+.
  #
  # Used by Minitar::Reader#each_entry to set the long name when processing GNU long
  # filename extensions.
  #
  # The +value+ must be the complete name, including leading directory components.
  def long_name=(value)
    valid_name!(value)

    @prefix = ""
    @name = value
  end

  # A string representation of the header.
  def to_s
    update_checksum
    header(@checksum)
  end
  alias_method :to_str, :to_s

  # TODO: In Minitar 2, PosixHeader#to_str will be removed.

  # Update the checksum field.
  def update_checksum
    hh = header(" " * 8)
    @checksum = oct(calculate_checksum(hh), 6)
  end

  private

  def valid_name!(value)
    return if value.is_a?(String) && !value.empty?
    raise ArgumentError, "Field name must be a non-empty string"
  end

  def oct(num, len)
    if num.nil?
      "\0" * (len + 1)
    else
      "%0#{len}o" % num
    end
  end

  def calculate_checksum(hdr)
    hdr.unpack("C*").inject(:+)
  end

  def header(chksum)
    arr = [name, oct(mode, 7), oct(uid, 7), oct(gid, 7), oct(size, 11),
      oct(mtime, 11), chksum, " ", typeflag, linkname, magic, version,
      uname, gname, oct(devmajor, 7), oct(devminor, 7), prefix]
    str = arr.pack(HEADER_PACK_FORMAT)
    str + "\0" * ((BLOCK_SIZE - str.bytesize) % BLOCK_SIZE)
  end

  ##
  # :attr_accessor: name
  # The name of the file. Required.
  #
  # By default, limited to 100 bytes, but may be up to BLOCK_SIZE bytes if using the
  # GNU long name tar extension.

  ##
  # :attr_accessor: size
  # The size of the file. Required.

  ##
  # :attr_reader: prefix
  # The prefix of the file; the path before #name. Limited to 155 bytes.
  # Required.

  ##
  # :attr_reader: mode
  # The Unix file mode of the file. Stored as an octal integer. Required.

  ##
  # :attr_reader: uid
  # The Unix owner user ID of the file. Stored as an octal integer.

  ##
  # :attr_reader: uname
  # The user name of the Unix owner of the file.

  ##
  # :attr_reader: gid
  # The Unix owner group ID of the file. Stored as an octal integer.

  ##
  # :attr_reader: gname
  # The group name of the Unix owner of the file.

  ##
  # :attr_reader: mtime
  # The modification time of the file in epoch seconds. Stored as an
  # octal integer.

  ##
  # :attr_reader: checksum
  # The checksum of the file. Stored as an octal integer. Calculated
  # before encoding the header as a string.

  ##
  # :attr_reader: typeflag
  # The type of record in the file.
  #
  # +0+::  Regular file. NULL should be treated as a synonym, for compatibility
  #        purposes.
  # +1+::  Hard link.
  # +2+::  Symbolic link.
  # +3+::  Character device node.
  # +4+::  Block device node.
  # +5+::  Directory.
  # +6+::  FIFO node.
  # +7+::  Reserved.
  # +L+::  GNU extension for long filenames when #name is <tt>././@LongLink</tt>.

  ##
  # :attr_reader: linkname
  # The target of the symbolic link.

  ##
  # :attr_reader: magic
  # Always "ustar\0".

  ##
  # :attr_reader: version
  # Always "00"

  ##
  # :attr_reader: devmajor
  # The major device ID. Not currently used.

  ##
  # :attr_reader: devminor
  # The minor device ID. Not currently used.
end

Returns true if the header is a PAX extended header which contains metadata for the next file entry.

to_s ()

Source

# File lib/minitar/posix_header.rb, line 184
def to_s
  update_checksum
  header(@checksum)
end

A string representation of the header.

update_checksum ()

Source

# File lib/minitar/posix_header.rb, line 193
def update_checksum
  hh = header(" " * 8)
  @checksum = oct(calculate_checksum(hh), 6)
end

Update the checksum field.

valid? (= empty? || @magic == MAGIC_BYTES)

Source

# File lib/minitar/posix_header.rb, line 160
  def valid? = empty? || @magic == MAGIC_BYTES

  # Returns +true+ if the header is a long name special header which indicates
  # that the next block of data is the filename.
  def long_name? = typeflag == "L" && name == GNU_EXT_LONG_LINK

  # Returns +true+ if the header is a PAX extended header which contains
  # metadata for the next file entry.
  def pax_header? = typeflag == "x"

  # Sets the +name+ to the +value+ provided and clears +prefix+.
  #
  # Used by Minitar::Reader#each_entry to set the long name when processing GNU long
  # filename extensions.
  #
  # The +value+ must be the complete name, including leading directory components.
  def long_name=(value)
    valid_name!(value)

    @prefix = ""
    @name = value
  end

  # A string representation of the header.
  def to_s
    update_checksum
    header(@checksum)
  end
  alias_method :to_str, :to_s

  # TODO: In Minitar 2, PosixHeader#to_str will be removed.

  # Update the checksum field.
  def update_checksum
    hh = header(" " * 8)
    @checksum = oct(calculate_checksum(hh), 6)
  end

  private

  def valid_name!(value)
    return if value.is_a?(String) && !value.empty?
    raise ArgumentError, "Field name must be a non-empty string"
  end

  def oct(num, len)
    if num.nil?
      "\0" * (len + 1)
    else
      "%0#{len}o" % num
    end
  end

  def calculate_checksum(hdr)
    hdr.unpack("C*").inject(:+)
  end

  def header(chksum)
    arr = [name, oct(mode, 7), oct(uid, 7), oct(gid, 7), oct(size, 11),
      oct(mtime, 11), chksum, " ", typeflag, linkname, magic, version,
      uname, gname, oct(devmajor, 7), oct(devminor, 7), prefix]
    str = arr.pack(HEADER_PACK_FORMAT)
    str + "\0" * ((BLOCK_SIZE - str.bytesize) % BLOCK_SIZE)
  end

  ##
  # :attr_accessor: name
  # The name of the file. Required.
  #
  # By default, limited to 100 bytes, but may be up to BLOCK_SIZE bytes if using the
  # GNU long name tar extension.

  ##
  # :attr_accessor: size
  # The size of the file. Required.

  ##
  # :attr_reader: prefix
  # The prefix of the file; the path before #name. Limited to 155 bytes.
  # Required.

  ##
  # :attr_reader: mode
  # The Unix file mode of the file. Stored as an octal integer. Required.

  ##
  # :attr_reader: uid
  # The Unix owner user ID of the file. Stored as an octal integer.

  ##
  # :attr_reader: uname
  # The user name of the Unix owner of the file.

  ##
  # :attr_reader: gid
  # The Unix owner group ID of the file. Stored as an octal integer.

  ##
  # :attr_reader: gname
  # The group name of the Unix owner of the file.

  ##
  # :attr_reader: mtime
  # The modification time of the file in epoch seconds. Stored as an
  # octal integer.

  ##
  # :attr_reader: checksum
  # The checksum of the file. Stored as an octal integer. Calculated
  # before encoding the header as a string.

  ##
  # :attr_reader: typeflag
  # The type of record in the file.
  #
  # +0+::  Regular file. NULL should be treated as a synonym, for compatibility
  #        purposes.
  # +1+::  Hard link.
  # +2+::  Symbolic link.
  # +3+::  Character device node.
  # +4+::  Block device node.
  # +5+::  Directory.
  # +6+::  FIFO node.
  # +7+::  Reserved.
  # +L+::  GNU extension for long filenames when #name is <tt>././@LongLink</tt>.

  ##
  # :attr_reader: linkname
  # The target of the symbolic link.

  ##
  # :attr_reader: magic
  # Always "ustar\0".

  ##
  # :attr_reader: version
  # Always "00"

  ##
  # :attr_reader: devmajor
  # The major device ID. Not currently used.

  ##
  # :attr_reader: devminor
  # The minor device ID. Not currently used.
end

Indicates if the header has a valid magic value.

valid_name! (value)

Source

# File lib/minitar/posix_header.rb, line 200
def valid_name!(value)
  return if value.is_a?(String) && !value.empty?
  raise ArgumentError, "Field name must be a non-empty string"
end

Public Instance Methods

name= (value)

Source

# File lib/minitar/posix_header.rb, line 51
def name=(value)
  valid_name!(value)
  @name = value
end

The name of the file. Required.

By default, limited to 100 bytes, but may be up to BLOCK_SIZE bytes if using the GNU long name tar extension.