TarFormat enum

A fully resolved tar format.

When we know that a tar entry must use a specific format, this is represented with a value from this TarFormat enum.

Inheritance

• Object
• Enum
• TarFormat

Implemented types

• MaybeTarFormat

Constructors

TarFormat(int _value, String _name)

const

Values

v7 → const TarFormat

Original Unix Version 7 (V7) AT&T tar tool prior to standardization.

The structure of the V7 Header consists of the following:

Start | End | Field

0 | 100 | Path name, stored as null-terminated string. 100 | 108 | File mode, stored as an octal number in ASCII. 108 | 116 | User id of owner, as octal number in ASCII. 116 | 124 | Group id of owner, as octal number in ASCII. 124 | 136 | Size of file, as octal number in ASCII. 136 | 148 | Modification time of file, number of seconds from epoch, stored as an octal number in ASCII. 148 | 156 | Header checksum, stored as an octal number in ASCII. 156 | 157 | Link flag, determines the kind of header. 157 | 257 | Link name, stored as a string. 257 | 512 | NUL pad.

Unused bytes are set to NUL ('\x00')s

Reference: https://www.freebsd.org/cgi/man.cgi?query=tar&sektion=5&format=html https://www.gnu.org/software/tar/manual/html_chapter/tar_15.html#SEC188 http://cdrtools.sourceforge.net/private/man/star/star.4.html

const TarFormat(1, 'V7')

ustar → const TarFormat

USTAR (Unix Standard TAR) header format defined in POSIX.1-1988.

The structure of the USTAR Header consists of the following:

Start | End | Field

0 | 100 | Path name, stored as null-terminated string. 100 | 108 | File mode, stored as an octal number in ASCII. 108 | 116 | User id of owner, as octal number in ASCII. 116 | 124 | Group id of owner, as octal number in ASCII. 124 | 136 | Size of file, as octal number in ASCII. 136 | 148 | Modification time of file, number of seconds from epoch, stored as an octal number in ASCII. 148 | 156 | Header checksum, stored as an octal number in ASCII. 156 | 157 | Type flag, determines the kind of header. Note that the meaning of the size field depends on the type. 157 | 257 | Link name, stored as a string. 257 | 263 | Contains the magic value "ustar\x00" to indicate that this is the USTAR format. Full compliance requires user name and group name fields to be set. 263 | 265 | Version. "00" for POSIX standard archives. 265 | 297 | User name, as null-terminated ASCII string. 297 | 329 | Group name, as null-terminated ASCII string. 329 | 337 | Major number for character or block device entry. 337 | 345 | Minor number for character or block device entry. 345 | 500 | Prefix. If the pathname is too long to fit in the 100 bytes provided at the start, it can be split at any / character with the first portion going here. 500 | 512 | NUL pad.

Unused bytes are set to NUL ('\x00')s

User and group names should be used in preference to uid/gid values when they are set and the corresponding names exist on the system.

While this format is compatible with most tar readers, the format has several limitations making it unsuitable for some usages. Most notably, it cannot support sparse files, files larger than 8GiB, filenames larger than 256 characters, and non-ASCII filenames.

Reference: https://www.freebsd.org/cgi/man.cgi?query=tar&sektion=5&format=html https://www.gnu.org/software/tar/manual/html_chapter/tar_15.html#SEC188 http://pubs.opengroup.org/onlinepubs/9699919799/utilities/pax.html#tag_20_92_13_06

const TarFormat(2, 'USTAR')

pax → const TarFormat

PAX header format defined in POSIX.1-2001.

PAX extends USTAR by writing a special file with either the x or g type flags to allow for attributes that are not conveniently stored in a POSIX ustar archive to be held.

Some newer formats add their own extensions to PAX by defining their own keys and assigning certain semantic meaning to the associated values. For example, sparse file support in PAX is implemented using keys defined by the GNU manual (e.g., "GNU.sparse.map").

Reference: https://www.freebsd.org/cgi/man.cgi?query=tar&sektion=5&format=html https://www.gnu.org/software/tar/manual/html_chapter/tar_15.html#SEC188 http://cdrtools.sourceforge.net/private/man/star/star.4.html http://pubs.opengroup.org/onlinepubs/009695399/utilities/pax.html

const TarFormat(4, 'PAX')

gnu → const TarFormat

GNU header format.

The GNU header format is older than the USTAR and PAX standards and is not compatible with them. The GNU format supports arbitrary file sizes, filenames of arbitrary encoding and length, sparse files, and other features.

Start | End | Field

0 | 100 | Path name, stored as null-terminated string. 100 | 108 | File mode, stored as an octal number in ASCII. 108 | 116 | User id of owner, as octal number in ASCII. 116 | 124 | Group id of owner, as octal number in ASCII. 124 | 136 | Size of file, as octal number in ASCII. 136 | 148 | Modification time of file, number of seconds from epoch, stored as an octal number in ASCII. 148 | 156 | Header checksum, stored as an octal number in ASCII. 156 | 157 | Type flag, determines the kind of header. Note that the meaning of the size field depends on the type. 157 | 257 | Link name, stored as a string. 257 | 263 | Contains the magic value "ustar " to indicate that this is the GNU format. 263 | 265 | Version. " \x00" for POSIX standard archives. 265 | 297 | User name, as null-terminated ASCII string. 297 | 329 | Group name, as null-terminated ASCII string. 329 | 337 | Major number for character or block device entry. 337 | 345 | Minor number for character or block device entry. 345 | 357 | Last Access time of file, number of seconds from epoch, stored as an octal number in ASCII. 357 | 369 | Last Changed time of file, number of seconds from epoch, stored as an octal number in ASCII. 369 | 381 | Offset - not used. 381 | 385 | Longnames - deprecated 385 | 386 | Unused. 386 | 482 | Sparse data - 4 sets of (offset, numbytes) stored as octal numbers in ASCII. 482 | 483 | isExtended - if this field is non-zero, this header is followed by additional sparse records, which are in the same format as above. 483 | 495 | Binary representation of the file's complete size, inclusive of the sparse data. 495 | 512 | NUL pad.

It is recommended that PAX be chosen over GNU unless the target application can only parse GNU formatted archives.

Reference: https://www.gnu.org/software/tar/manual/html_node/Standard.html

const TarFormat(8, 'GNU')

star → const TarFormat

Schily's TAR format, which is incompatible with USTAR. This does not cover STAR extensions to the PAX format; these fall under the PAX format.

Start | End | Field

0 | 100 | Path name, stored as null-terminated string. 100 | 108 | File mode, stored as an octal number in ASCII. 108 | 116 | User id of owner, as octal number in ASCII. 116 | 124 | Group id of owner, as octal number in ASCII. 124 | 136 | Size of file, as octal number in ASCII. 136 | 148 | Modification time of file, number of seconds from epoch, stored as an octal number in ASCII. 148 | 156 | Header checksum, stored as an octal number in ASCII. 156 | 157 | Type flag, determines the kind of header. Note that the meaning of the size field depends on the type. 157 | 257 | Link name, stored as a string. 257 | 263 | Contains the magic value "ustar\x00" to indicate that this is the GNU format. 263 | 265 | Version. "00" for STAR archives. 265 | 297 | User name, as null-terminated ASCII string. 297 | 329 | Group name, as null-terminated ASCII string. 329 | 337 | Major number for character or block device entry. 337 | 345 | Minor number for character or block device entry. 345 | 476 | Prefix. If the pathname is too long to fit in the 100 bytes provided at the start, it can be split at any / character with the first portion going here. 476 | 488 | Last Access time of file, number of seconds from epoch, stored as an octal number in ASCII. 488 | 500 | Last Changed time of file, number of seconds from epoch, stored as an octal number in ASCII. 500 | 508 | NUL pad. 508 | 512 | Trailer - "tar\x00".

Reference: http://cdrtools.sourceforge.net/private/man/star/star.4.html

const TarFormat(16, 'STAR')

Properties

hashCode → int

The hash code for this object.

no setter, inherited

index → int

A numeric identifier for the enumerated value.

no setter, inherited

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

valid → bool

Returns if this format might be valid.

no setter, override

Methods

has(MaybeTarFormat other) → bool

Returns if other is a possible resolution of this.

override

mayOnlyBe(MaybeTarFormat other) → MaybeTarFormat

Returns a new TarFormat that signifies that it can only be other's format.

override

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

toString() → String

A string representation of this object.

override

Operators

operator ==(Object other) → bool

The equality operator.

inherited

operator |(TarFormat other) → MaybeTarFormat

Returns a new MaybeTarFormat that signifies that it can be either this or other's format.

override

Constants

values → const List<TarFormat>

A constant List of the values in this enum, in order of their declaration.