tar-wasi 0.4.38

A Rust implementation of a TAR file reader and writer. This library does not currently handle compression, but it is abstract over all I/O readers and writers. Additionally, great lengths are taken to ensure that the entire contents are never required to be entirely resident in memory all at once. This fork includes full support for running the library with WebAssembly via the target wasm32-wasi.
Documentation
#![cfg(not(target_os = "wasi"))]
extern crate tar;
extern crate tempfile;

use std::fs::{create_dir, File};
use std::io::Read;

use tempfile::Builder;

macro_rules! t {
    ($e:expr) => {
        match $e {
            Ok(v) => v,
            Err(e) => panic!("{} returned {}", stringify!($e), e),
        }
    };
}

#[test]
fn absolute_symlink() {
    let mut ar = tar::Builder::new(Vec::new());

    let mut header = tar::Header::new_gnu();
    header.set_size(0);
    header.set_entry_type(tar::EntryType::Symlink);
    t!(header.set_path("foo"));
    t!(header.set_link_name("/bar"));
    header.set_cksum();
    t!(ar.append(&header, &[][..]));

    let bytes = t!(ar.into_inner());
    let mut ar = tar::Archive::new(&bytes[..]);

    let td = t!(Builder::new().prefix("tar").tempdir());
    t!(ar.unpack(td.path()));

    t!(td.path().join("foo").symlink_metadata());

    let mut ar = tar::Archive::new(&bytes[..]);
    let mut entries = t!(ar.entries());
    let entry = t!(entries.next().unwrap());
    assert_eq!(&*entry.link_name_bytes().unwrap(), b"/bar");
}

#[test]
fn absolute_hardlink() {
    let td = t!(Builder::new().prefix("tar").tempdir());
    let mut ar = tar::Builder::new(Vec::new());

    let mut header = tar::Header::new_gnu();
    header.set_size(0);
    header.set_entry_type(tar::EntryType::Regular);
    t!(header.set_path("foo"));
    header.set_cksum();
    t!(ar.append(&header, &[][..]));

    let mut header = tar::Header::new_gnu();
    header.set_size(0);
    header.set_entry_type(tar::EntryType::Link);
    t!(header.set_path("bar"));
    // This absolute path under tempdir will be created at unpack time
    t!(header.set_link_name(td.path().join("foo")));
    header.set_cksum();
    t!(ar.append(&header, &[][..]));

    let bytes = t!(ar.into_inner());
    let mut ar = tar::Archive::new(&bytes[..]);

    t!(ar.unpack(td.path()));
    t!(td.path().join("foo").metadata());
    t!(td.path().join("bar").metadata());
}

#[test]
fn relative_hardlink() {
    let mut ar = tar::Builder::new(Vec::new());

    let mut header = tar::Header::new_gnu();
    header.set_size(0);
    header.set_entry_type(tar::EntryType::Regular);
    t!(header.set_path("foo"));
    header.set_cksum();
    t!(ar.append(&header, &[][..]));

    let mut header = tar::Header::new_gnu();
    header.set_size(0);
    header.set_entry_type(tar::EntryType::Link);
    t!(header.set_path("bar"));
    t!(header.set_link_name("foo"));
    header.set_cksum();
    t!(ar.append(&header, &[][..]));

    let bytes = t!(ar.into_inner());
    let mut ar = tar::Archive::new(&bytes[..]);

    let td = t!(Builder::new().prefix("tar").tempdir());
    t!(ar.unpack(td.path()));
    t!(td.path().join("foo").metadata());
    t!(td.path().join("bar").metadata());
}

#[test]
fn absolute_link_deref_error() {
    let mut ar = tar::Builder::new(Vec::new());

    let mut header = tar::Header::new_gnu();
    header.set_size(0);
    header.set_entry_type(tar::EntryType::Symlink);
    t!(header.set_path("foo"));
    t!(header.set_link_name("/"));
    header.set_cksum();
    t!(ar.append(&header, &[][..]));

    let mut header = tar::Header::new_gnu();
    header.set_size(0);
    header.set_entry_type(tar::EntryType::Regular);
    t!(header.set_path("foo/bar"));
    header.set_cksum();
    t!(ar.append(&header, &[][..]));

    let bytes = t!(ar.into_inner());
    let mut ar = tar::Archive::new(&bytes[..]);

    let td = t!(Builder::new().prefix("tar").tempdir());
    assert!(ar.unpack(td.path()).is_err());
    t!(td.path().join("foo").symlink_metadata());
    assert!(File::open(td.path().join("foo").join("bar")).is_err());
}

#[test]
fn relative_link_deref_error() {
    let mut ar = tar::Builder::new(Vec::new());

    let mut header = tar::Header::new_gnu();
    header.set_size(0);
    header.set_entry_type(tar::EntryType::Symlink);
    t!(header.set_path("foo"));
    t!(header.set_link_name("../../../../"));
    header.set_cksum();
    t!(ar.append(&header, &[][..]));

    let mut header = tar::Header::new_gnu();
    header.set_size(0);
    header.set_entry_type(tar::EntryType::Regular);
    t!(header.set_path("foo/bar"));
    header.set_cksum();
    t!(ar.append(&header, &[][..]));

    let bytes = t!(ar.into_inner());
    let mut ar = tar::Archive::new(&bytes[..]);

    let td = t!(Builder::new().prefix("tar").tempdir());
    assert!(ar.unpack(td.path()).is_err());
    t!(td.path().join("foo").symlink_metadata());
    assert!(File::open(td.path().join("foo").join("bar")).is_err());
}

#[test]
#[cfg(unix)]
fn directory_maintains_permissions() {
    use ::std::os::unix::fs::PermissionsExt;

    let mut ar = tar::Builder::new(Vec::new());

    let mut header = tar::Header::new_gnu();
    header.set_size(0);
    header.set_entry_type(tar::EntryType::Directory);
    t!(header.set_path("foo"));
    header.set_mode(0o777);
    header.set_cksum();
    t!(ar.append(&header, &[][..]));

    let bytes = t!(ar.into_inner());
    let mut ar = tar::Archive::new(&bytes[..]);

    let td = t!(Builder::new().prefix("tar").tempdir());
    t!(ar.unpack(td.path()));
    let f = t!(File::open(td.path().join("foo")));
    let md = t!(f.metadata());
    assert!(md.is_dir());
    assert_eq!(md.permissions().mode(), 0o40777);
}

#[test]
#[cfg(not(windows))] // dangling symlinks have weird permissions
fn modify_link_just_created() {
    let mut ar = tar::Builder::new(Vec::new());

    let mut header = tar::Header::new_gnu();
    header.set_size(0);
    header.set_entry_type(tar::EntryType::Symlink);
    t!(header.set_path("foo"));
    t!(header.set_link_name("bar"));
    header.set_cksum();
    t!(ar.append(&header, &[][..]));

    let mut header = tar::Header::new_gnu();
    header.set_size(0);
    header.set_entry_type(tar::EntryType::Regular);
    t!(header.set_path("bar/foo"));
    header.set_cksum();
    t!(ar.append(&header, &[][..]));

    let mut header = tar::Header::new_gnu();
    header.set_size(0);
    header.set_entry_type(tar::EntryType::Regular);
    t!(header.set_path("foo/bar"));
    header.set_cksum();
    t!(ar.append(&header, &[][..]));

    let bytes = t!(ar.into_inner());
    let mut ar = tar::Archive::new(&bytes[..]);

    let td = t!(Builder::new().prefix("tar").tempdir());
    t!(ar.unpack(td.path()));

    t!(File::open(td.path().join("bar/foo")));
    t!(File::open(td.path().join("bar/bar")));
    t!(File::open(td.path().join("foo/foo")));
    t!(File::open(td.path().join("foo/bar")));
}

#[test]
#[cfg(not(windows))] // dangling symlinks have weird permissions
fn modify_outside_with_relative_symlink() {
    let mut ar = tar::Builder::new(Vec::new());

    let mut header = tar::Header::new_gnu();
    header.set_size(0);
    header.set_entry_type(tar::EntryType::Symlink);
    t!(header.set_path("symlink"));
    t!(header.set_link_name(".."));
    header.set_cksum();
    t!(ar.append(&header, &[][..]));

    let mut header = tar::Header::new_gnu();
    header.set_size(0);
    header.set_entry_type(tar::EntryType::Regular);
    t!(header.set_path("symlink/foo/bar"));
    header.set_cksum();
    t!(ar.append(&header, &[][..]));

    let bytes = t!(ar.into_inner());
    let mut ar = tar::Archive::new(&bytes[..]);

    let td = t!(Builder::new().prefix("tar").tempdir());
    let tar_dir = td.path().join("tar");
    create_dir(&tar_dir).unwrap();
    assert!(ar.unpack(tar_dir).is_err());
    assert!(!td.path().join("foo").exists());
}

#[test]
fn parent_paths_error() {
    let mut ar = tar::Builder::new(Vec::new());

    let mut header = tar::Header::new_gnu();
    header.set_size(0);
    header.set_entry_type(tar::EntryType::Symlink);
    t!(header.set_path("foo"));
    t!(header.set_link_name(".."));
    header.set_cksum();
    t!(ar.append(&header, &[][..]));

    let mut header = tar::Header::new_gnu();
    header.set_size(0);
    header.set_entry_type(tar::EntryType::Regular);
    t!(header.set_path("foo/bar"));
    header.set_cksum();
    t!(ar.append(&header, &[][..]));

    let bytes = t!(ar.into_inner());
    let mut ar = tar::Archive::new(&bytes[..]);

    let td = t!(Builder::new().prefix("tar").tempdir());
    assert!(ar.unpack(td.path()).is_err());
    t!(td.path().join("foo").symlink_metadata());
    assert!(File::open(td.path().join("foo").join("bar")).is_err());
}

#[test]
#[cfg(unix)]
fn good_parent_paths_ok() {
    use std::path::PathBuf;
    let mut ar = tar::Builder::new(Vec::new());

    let mut header = tar::Header::new_gnu();
    header.set_size(0);
    header.set_entry_type(tar::EntryType::Symlink);
    t!(header.set_path(PathBuf::from("foo").join("bar")));
    t!(header.set_link_name(PathBuf::from("..").join("bar")));
    header.set_cksum();
    t!(ar.append(&header, &[][..]));

    let mut header = tar::Header::new_gnu();
    header.set_size(0);
    header.set_entry_type(tar::EntryType::Regular);
    t!(header.set_path("bar"));
    header.set_cksum();
    t!(ar.append(&header, &[][..]));

    let bytes = t!(ar.into_inner());
    let mut ar = tar::Archive::new(&bytes[..]);

    let td = t!(Builder::new().prefix("tar").tempdir());
    t!(ar.unpack(td.path()));
    t!(td.path().join("foo").join("bar").read_link());
    let dst = t!(td.path().join("foo").join("bar").canonicalize());
    t!(File::open(dst));
}

#[test]
fn modify_hard_link_just_created() {
    let mut ar = tar::Builder::new(Vec::new());

    let mut header = tar::Header::new_gnu();
    header.set_size(0);
    header.set_entry_type(tar::EntryType::Link);
    t!(header.set_path("foo"));
    t!(header.set_link_name("../test"));
    header.set_cksum();
    t!(ar.append(&header, &[][..]));

    let mut header = tar::Header::new_gnu();
    header.set_size(1);
    header.set_entry_type(tar::EntryType::Regular);
    t!(header.set_path("foo"));
    header.set_cksum();
    t!(ar.append(&header, &b"x"[..]));

    let bytes = t!(ar.into_inner());
    let mut ar = tar::Archive::new(&bytes[..]);

    let td = t!(Builder::new().prefix("tar").tempdir());

    let test = td.path().join("test");
    t!(File::create(&test));

    let dir = td.path().join("dir");
    assert!(ar.unpack(&dir).is_err());

    let mut contents = Vec::new();
    t!(t!(File::open(&test)).read_to_end(&mut contents));
    assert_eq!(contents.len(), 0);
}

#[test]
fn modify_symlink_just_created() {
    let mut ar = tar::Builder::new(Vec::new());

    let mut header = tar::Header::new_gnu();
    header.set_size(0);
    header.set_entry_type(tar::EntryType::Symlink);
    t!(header.set_path("foo"));
    t!(header.set_link_name("../test"));
    header.set_cksum();
    t!(ar.append(&header, &[][..]));

    let mut header = tar::Header::new_gnu();
    header.set_size(1);
    header.set_entry_type(tar::EntryType::Regular);
    t!(header.set_path("foo"));
    header.set_cksum();
    t!(ar.append(&header, &b"x"[..]));

    let bytes = t!(ar.into_inner());
    let mut ar = tar::Archive::new(&bytes[..]);

    let td = t!(Builder::new().prefix("tar").tempdir());

    let test = td.path().join("test");
    t!(File::create(&test));

    let dir = td.path().join("dir");
    t!(ar.unpack(&dir));

    let mut contents = Vec::new();
    t!(t!(File::open(&test)).read_to_end(&mut contents));
    assert_eq!(contents.len(), 0);
}