Struct PosixHeader

#[repr(C, packed(1))]
pub struct PosixHeader {

    pub name: TarFormatString<NAME_LEN>,
    pub mode: Mode,
    pub uid: TarFormatOctal<8>,
    pub gid: TarFormatOctal<8>,
    pub size: TarFormatOctal<12>,
    pub mtime: TarFormatDecimal<12>,
    pub cksum: TarFormatOctal<8>,
    pub typeflag: TypeFlagRaw,
    pub linkname: TarFormatString<NAME_LEN>,
    pub magic: TarFormatString<6>,
    pub version: TarFormatString<2>,
    pub uname: TarFormatString<32>,
    pub gname: TarFormatString<32>,
    pub dev_major: TarFormatOctal<8>,
    pub dev_minor: TarFormatOctal<8>,
    pub prefix: TarFormatString<PREFIX_LEN>,
    pub _pad: [u8; 12],
}

Header of the TAR format as specified by POSIX (POSIX 1003.1-1990).

“New” GNU Tar versions use this archive format by default. (https://www.gnu.org/software/tar/manual/html_node/Formats.html#Formats).

Each file is started by such a header, that describes the size and the file name. After that, the file content stands in chunks of 512 bytes. The number of bytes can be derived from the file size.

This is also mostly compatible with the “Ustar”-header and the “GNU format”. Because this library mainly targets the filename, the data, and basic metadata, we don’t need advanced checks for specific extensions.

Fields

name: TarFormatString<NAME_LEN>

mode: Mode

uid: TarFormatOctal<8>

gid: TarFormatOctal<8>

size: TarFormatOctal<12>

mtime: TarFormatDecimal<12>

cksum: TarFormatOctal<8>

typeflag: TypeFlagRaw

linkname: TarFormatString<NAME_LEN>

Name. There is always a null byte, therefore the max len is 99.

magic: TarFormatString<6>

version: TarFormatString<2>

uname: TarFormatString<32>

Username. There is always a null byte, therefore the max len is N-1.

gname: TarFormatString<32>

Groupname. There is always a null byte, therefore the max len is N-1.

dev_major: TarFormatOctal<8>

dev_minor: TarFormatOctal<8>

prefix: TarFormatString<PREFIX_LEN>

_pad: [u8; 12]

Implementations

impl PosixHeader

pub fn payload_block_count(&self) -> Result<usize, ParseIntError>

Returns the number of blocks that are required to read the whole file content. Returns an error, if the file size can’t be parsed from the header.

pub fn is_zero_block(&self) -> bool

A Tar archive is terminated, if an end-of-archive entry, which consists of two 512 blocks of zero bytes, is found.

Trait Implementations

impl Clone for PosixHeader

fn clone(&self) -> PosixHeader

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for PosixHeader

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq for PosixHeader

fn eq(&self, other: &PosixHeader) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for PosixHeader

impl Eq for PosixHeader

impl StructuralPartialEq for PosixHeader