sit/

lib.rs

#![doc = include_str!("../README.md")]
#![feature(seek_stream_len)]
#![feature(unsafe_cell_access)]
#![feature(get_mut_unchecked)]

use std::fs;
use std::io;
use std::io::Read;
use std::path;

use fourcc::{FourCC, fourcc};
pub use macintosh_utils::Fork;

/// Implementation of the various decompression methods that are used in StuffIt archives
pub mod algos;
/// Data structures that make up the structure of archives
pub mod structs;

mod archive;
mod entry;
pub mod error;
pub(crate) mod verify;

pub use archive::Archive;
pub use archive::EntryIterator;
pub use archive::EntryReader;
pub use archive::ReadableEntry;
pub use entry::Entry;
pub use error::Error;
pub use verify::{VerifyingEntryReader, VerifyingIterator};

use crate::error::ExtractionError;

pub fn verify<R: io::Read + io::Seek>(_reader: R) -> Result<(), Error> {
    todo!()
}

pub fn verify_path<P: AsRef<path::Path>>(path: P) -> Result<(), Error> {
    let file = fs::File::open(path)?;
    verify(file)
}

pub fn probe<R: io::Read + io::Seek>(reader: R) -> Result<(FourCC, FourCC), Error> {
    let archive = Archive::try_from(reader)?;

    match archive.header() {
        structs::ArchiveHeader::V1(archive_header) => {
            Ok((fourcc!("rLau"), archive_header.file_code))
        }
        structs::ArchiveHeader::V5(_) => Ok((fourcc!("rLau"), fourcc!("SIT!"))),
    }
}

/// Extract data from the first file entry denoted by `file_name`
pub fn extract_file<R: io::Read + io::Seek>(
    reader: R,
    file_name: &str,
    fork: Fork,
) -> Result<Vec<u8>, ExtractionError> {
    let mut archive = Archive::try_from(reader)?;
    let Some(entry) = archive
        .iter()
        .find(|e| e.is_file() && e.name() == file_name)
    else {
        return Err(ExtractionError::ItemNotFound);
    };

    let mut data = vec![0u8; entry.uncompressed_size(fork)];
    let mut reader = archive.open_fork(&entry, fork)?;
    reader.read_exact(&mut data)?;

    Ok(data)
}

/// Extract data from nth file entry in the archive
pub fn extract_file_by_index<R: io::Read + io::Seek>(
    reader: R,
    index: usize,
    fork: Fork,
) -> Result<Vec<u8>, ExtractionError> {
    let mut archive = Archive::try_from(reader)?;
    let Some(entry) = archive
        .iter()
        .find(|e| matches!(e, Entry::File(f) if f.index() == index))
    else {
        return Err(ExtractionError::ItemNotFound);
    };

    let mut data = vec![0u8; entry.uncompressed_size(fork)];
    let mut reader = archive.open_fork(&entry, fork)?;
    reader.read_exact(&mut data)?;

    Ok(data)
}

#[cfg(test)]
mod test {
    use fourcc::fourcc;
    use macintosh_utils::decode_string;

    use crate::{archive::ReadableEntry, error::UnsupportedFeature};

    use super::*;
    use std::{
        fs::{File, exists},
        io::{self, Seek as _},
        panic,
        path::PathBuf,
    };

    macro_rules! assert_ok {
        ($expression:expr) => {
            match $expression {
                Ok(_) => (),
                Err(e) => {
                    panic!(
                        "Expected {} not to return an error, but got {:?} instead",
                        stringify!($expression),
                        e
                    );
                }
            }
        };
    }

    macro_rules! assert_err {
        ($expression:expr) => {
            match $expression {
                Ok(val) => panic!(
                    "Expected {} return an error, but got Ok({:?}) instead",
                    stringify!($expression),
                    val
                ),
                Err(_) => {
                    assert!(true);
                }
            }
        };
    }

    #[test]
    #[should_panic]
    fn exclusive_archive_access_enforcement_with_multiple_iterators() {
        let archive = open_fixture("StuffIt 1.10 Moby Dick.sit");

        let _iterator = archive.iter();
        let _iterator = archive.iter();
    }

    #[test]
    #[should_panic]
    fn exclusive_archive_access_enforcement_with_resetting() {
        let mut archive = open_fixture("StuffIt 1.10 Moby Dick.sit");

        let _iterator = archive.iter();
        let _ = archive.reset();
    }

    #[test]
    fn simple_file_extraction() {
        let reader = open_fixture_raw("StuffIt 1.10 Moby Dick.sit");
        let data = extract_file(reader, "00b Title.txt", Fork::Data).unwrap();
        let contents = String::from_utf8_lossy(&data);

        assert!(contents.contains("MOBY-DICK"));
    }

    #[test]
    fn missing_file_extraction() {
        let reader = open_fixture_raw("StuffIt 1.10 Moby Dick.sit");
        let result = extract_file(reader, "i don't exist", Fork::Data);
        assert!(matches!(result, Err(ExtractionError::ItemNotFound)));
    }

    #[test]
    fn simple_file_extraction_by_index() {
        let reader = open_fixture_raw("StuffIt 1.10 Moby Dick.sit");
        let data = extract_file_by_index(reader, 1, Fork::Data).unwrap();
        let contents = String::from_utf8_lossy(&data);

        assert!(contents.contains("MOBY-DICK"));
    }

    #[test]
    fn missing_file_extraction_by_index() {
        let reader = open_fixture_raw("StuffIt 1.10 Moby Dick.sit");
        let result = extract_file_by_index(reader, 823, Fork::Data);
        assert!(matches!(result, Err(ExtractionError::ItemNotFound)));
    }

    // TODO: Enable test when header verification has been implemented
    #[allow(unused)]
    fn header_corruption() {
        let mut fixture = open_fixture_raw("StuffIt 1.10 Moby Dick.sit");
        let mut buffer = vec![0u8; fixture.stream_len().unwrap() as usize];
        fixture.read_exact(&mut buffer).unwrap();

        // corrupt file header in an insignificant way (change file code)
        buffer[0x58] = b'_';

        let cursor = io::Cursor::new(buffer);
        let mut reader = Archive::try_from(cursor).unwrap();
        let result = reader.verify();

        assert!(matches!(
            result,
            Err(Error::ChecksumMismatch(
                error::ChecksumLocation::EntryHeader
            ))
        ));
    }

    #[test]
    fn reading_empty_archive() {
        let mut archive = open_fixture("StuffIt 1.10 empty.sit");
        assert_ok!(archive.verify());
    }

    #[test]
    fn stuffit_1_5_1() {
        let mut archive = open_fixture("StuffIt 1.5.1.sit");
        assert_ok!(archive.verify());
    }

    mod stuffit_1_10 {
        use super::*;

        #[test]
        fn item_extraction() {
            let mut archive = open_fixture("StuffIt 1.10 Moby Dick.sit");
            let entry = archive
                .iter()
                .find(|e| e.is_file() && e.name() == "00b Title.txt")
                .unwrap();

            let mut data = vec![0u8; entry.uncompressed_size(Fork::Data)];
            let mut stream = archive.open_fork(&entry, Fork::Data).unwrap();
            let bytes_read = stream.read(&mut data).unwrap();
            assert_eq!(bytes_read, entry.uncompressed_size(Fork::Data));
            assert_eq!(data.len(), 47);

            let string = decode_string(data);
            assert!(string.contains("MOBY-DICK"));
            assert!(string.contains("Herman Melville"));
        }

        #[test]
        fn streaming_verification() {
            use crate as sit;

            let mut archive_file = open_fixture_raw("StuffIt 1.10 Moby Dick.sit");
            let mut archive_data = vec![0u8; archive_file.stream_len().unwrap() as usize];
            archive_file.read_exact(&mut archive_data).unwrap();
            let reader = io::Cursor::new(archive_data);
            let mut archive = sit::Archive::try_from(reader).unwrap();

            let entry = archive
                .iter()
                .find(|e| e.is_file() && e.name() == "00b Title.txt")
                .unwrap();
            let offset_in_archive = entry.offset(Fork::Data);

            let mut data = vec![0u8; entry.uncompressed_size(Fork::Data)];

            //Read data from the unmodified (valid) archive
            let mut stream = archive.open_fork(&entry, Fork::Data).unwrap().verifying();
            assert_ok!(stream.read_exact(&mut data));

            // Now let's corrupt some data in the archive
            let mut archive_data = archive.into_inner().into_inner();
            archive_data[offset_in_archive as usize + 12] = 0xAB;

            let reader = io::Cursor::new(archive_data);
            let mut archive = sit::Archive::try_from(reader).unwrap();

            let mut stream = archive.open_fork(&entry, Fork::Data).unwrap().verifying();

            // The read operation returns an error when the end of the stream has been reached
            assert_err!(stream.read_exact(&mut data));
        }

        #[test]
        fn full_verification() {
            let mut fixture = open_fixture("StuffIt 1.10 Moby Dick.sit");
            assert_ok!(fixture.verify());
        }

        #[test]
        fn edge_cases() {
            let mut fixture = open_fixture("StuffIt 1.10 edge cases.sit");
            assert_ok!(fixture.verify());
        }

        #[test]
        fn stream_validation() {
            let mut archive = open_fixture("StuffIt 1.10 Moby Dick.sit");
            let entry = archive
                .iter()
                .find(|e| e.is_file() && e.name() == "00b Title.txt")
                .unwrap();

            assert_ok!(
                archive
                    .open_fork(&entry, Fork::Data)
                    .unwrap()
                    .verifying()
                    .slurp()
            );

            assert_ok!(
                archive
                    .open_fork(&entry, Fork::Resource)
                    .unwrap()
                    .verifying()
                    .slurp()
            );
        }
    }

    mod stuffit_deluxe_4_5 {
        use super::*;

        #[test]
        fn full_verification() {
            let mut fixture = open_fixture("StuffIt DLX 4.5.sit");
            assert_ok!(fixture.verify());
        }

        #[test]
        fn offset_after_archive_header() {
            let mut archive = open_fixture("StuffIt DLX 4.5 Offset.sit");
            assert_ok!(archive.verify());
        }

        #[test]
        fn encrypted_entries() {
            let mut archive = open_fixture("StuffIt DLX 4.5 Encrypted.sit");
            assert!(matches!(
                archive.verify(),
                Err(Error::UnsupportedFeature(UnsupportedFeature::Encryption))
            ));
        }

        #[test]
        fn self_extracting() {
            let mut archive = open_fixture("StuffIt DLX 4.5 Self-Extracting.sea");
            assert_ok!(archive.verify());
        }

        #[test]
        fn entry_count() {
            let mut archive = open_fixture("StuffIt DLX 4.5.sit");
            let files = archive.iter().filter(|e| matches!(e, Entry::File(_)));

            assert_eq!(files.count(), 144);

            archive.reset().unwrap();
            let directories = archive.iter().filter(|e| matches!(e, Entry::Directory(_)));
            assert_eq!(directories.count(), 6);
        }
    }

    mod stuffit_deluxe_5_5 {
        use super::*;

        #[test]
        fn entry_count() {
            let archive = open_fixture("StuffIt DLX 5.5 Moby Dick.sit");
            let entry_count = archive.iter().count();
            let directory_count = archive.iter().filter(|f| f.is_directory()).count();
            let file_count = archive.iter().filter(|f| f.is_file()).count();

            assert_eq!(directory_count, 4);
            assert_eq!(file_count, 140);
            assert_eq!(
                entry_count,
                file_count + directory_count * 2,
                "Should have see one directory-end marker per directory"
            );
        }

        #[test]
        fn folder_comment() {
            let archive = open_fixture("StuffIt DLX 5.5 Folder Comment.sit");
            let folder = archive.iter().find(|e| e.is_directory()).unwrap();
            assert_eq!(folder.name(), "Folder with comments");
            assert_eq!(folder.comment(), "A folder with a comment!");

            let archive = open_fixture("StuffIt DLX 5.5 Folder Comment.sit");
            let file = archive.iter().find(|e| e.is_file()).unwrap();
            let Entry::File(file) = file else { panic!() };

            assert_eq!(file.file_code(), fourcc!("TEXT"));
            assert_eq!(file.creator(), fourcc!("ttxt"));
        }

        #[test]
        fn file_comment() {
            let archive = open_fixture("StuffIt DLX 5.5 File Comment.sit");
            let file = archive.iter().find(|e| e.is_file()).unwrap();
            assert_eq!(file.name(), "File with comments.txt");
            assert_eq!(file.comment(), "Look! This is a file comment!");
            let Entry::File(file) = file else { panic!() };
            assert_eq!(file.file_code(), fourcc!("TEXT"));
            assert_eq!(file.creator(), fourcc!("ttxt"));
        }

        #[test]
        fn encrypted_entries() {
            let mut archive = open_fixture("StuffIt DLX 5.5.sit");
            assert!(matches!(
                archive.verify(),
                Err(Error::UnsupportedFeature(UnsupportedFeature::Encryption))
            ));
        }
    }

    #[test]
    fn stuffit_131_comment() {
        let mut archive = open_fixture("StuffIt 1.31 Comment.sit");
        assert_ok!(archive.verify());
    }

    #[test]
    fn stuffit_131() {
        let mut archive = open_fixture("StuffIt 1.31.sit");
        assert_ok!(archive.verify());
    }

    #[test]
    fn stuffit_201_comment() {
        let mut archive = open_fixture("StuffIt 2.0.1 Comment.sit");
        assert_ok!(archive.verify());
    }

    #[test]
    fn stuffit_201_encryption_methods() {
        let mut archive = open_fixture("StuffIt 2.0.1 Encryption Methods.sit");
        assert!(matches!(
            archive.verify(),
            Err(Error::UnsupportedFeature(UnsupportedFeature::Encryption))
        ));
    }

    #[test]
    fn stuffit_201_compression_methods() {
        let mut archive = open_fixture("StuffIt 2.0.1 Compression Methods.sit");
        assert_ok!(archive.verify());
    }

    #[test]
    fn stuffit_201_fixed_huffman() {
        let mut archive = open_fixture("StuffIt 2.0.1 Fixed Huffman.sit");
        assert_ok!(archive.verify());
    }

    #[test]
    fn stuffit_201_signature() {
        let mut archive = open_fixture("StuffIt 2.0.1 Signature.sit");
        assert_ok!(archive.verify());
    }

    #[test]
    fn stuffit_201() {
        let mut archive = open_fixture("StuffIt 2.0.1.sit");
        assert_ok!(archive.verify());
    }

    #[test]
    fn stuffit_201_best_guess() {
        let mut archive = open_fixture("StuffIt 2.0.1 Best Guess.sit");
        assert_ok!(archive.verify());
    }

    #[test]
    fn stuffit_201_better_compression() {
        let mut archive = open_fixture("StuffIt 2.0.1 Better Compression.sit");
        assert_ok!(archive.verify());
    }

    #[test]
    fn stuffit_201_fast() {
        let mut archive = open_fixture("StuffIt 2.0.1 Fast.sit");
        assert_ok!(archive.verify());
    }

    #[test]
    fn stuffit_201_faster() {
        let mut archive = open_fixture("StuffIt 2.0.1 Faster.sit");
        assert_ok!(archive.verify());
    }

    #[test]
    fn stuffit_201_optimal() {
        let mut archive = open_fixture("StuffIt 2.0.1 Optimal.sit");
        assert_ok!(archive.verify());
    }

    #[test]
    fn stuffit_351() {
        let mut archive = open_fixture("StuffIt 3.5.1.sit");
        assert_ok!(archive.verify());
    }

    #[test]
    fn stuffit_40() {
        let mut archive = open_fixture("StuffIt 4.0.sit");
        assert_ok!(archive.verify());
    }

    #[test]
    fn stuffit_45() {
        let mut archive = open_fixture("StuffIt 4.5.sit");
        assert_ok!(archive.verify());
    }

    #[test]
    fn stuffit_55_comment() {
        let mut archive = open_fixture("StuffIt 5.5 Comment.sit");
        assert_ok!(archive.verify());
    }

    #[test]
    fn stuffit_55() {
        let mut archive = open_fixture("StuffIt 5.5.sit");
        assert_ok!(archive.verify());
    }

    #[test]
    fn stuffit_60_receipt() {
        let mut archive = open_fixture("StuffIt 6.0 Receipt.sit");
        assert_ok!(archive.verify());
    }

    #[test]
    fn stuffit_60() {
        let mut archive = open_fixture("StuffIt 6.0.sit");
        assert_ok!(archive.verify());
    }

    #[test]
    fn stuffit_703() {
        let mut archive = open_fixture("StuffIt 7.0.3.sit");
        assert_ok!(archive.verify());
    }

    #[test]
    fn stuffit_703_without_finder_desktop_files() {
        let mut archive = open_fixture("StuffIt 7.0.3 wihout Finder.sit");
        assert_ok!(archive.verify());
    }

    fn open_fixture_raw(name: &'static str) -> File {
        let path = PathBuf::from(env!("CARGO_MANIFEST_DIR"))
            .join("test/")
            .join(name);

        if !exists(&path).unwrap() {
            panic!("Test fixture {name} does not exist!");
        }

        std::fs::File::open(path).unwrap()
    }

    fn open_fixture(name: &'static str) -> Archive<File> {
        let file = open_fixture_raw(name);
        Archive::try_from(file).unwrap()
    }
}