luminol_filesystem/archiver/filesystem/

impls.rs

// Copyright (C) 2024 Melody Madeline Lyons
//
// This file is part of Luminol.
//
// Luminol is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Luminol is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Luminol.  If not, see <http://www.gnu.org/licenses/>.

use color_eyre::eyre::WrapErr;
use itertools::Itertools;
use rand::Rng;
use std::io::{
    prelude::*,
    BufReader, BufWriter,
    ErrorKind::{AlreadyExists, InvalidData},
    SeekFrom,
};

use super::super::util::{
    advance_magic, move_file_and_truncate, read_file_xor, read_u32_xor, regress_magic,
};
use super::{Entry, File, FileSystem, MAGIC};
use crate::{DirEntry, Error, Metadata, OpenFlags, Result};

impl<T> crate::FileSystem for FileSystem<T>
where
    T: crate::File,
{
    type File = File<T>;

    fn open_file(
        &self,
        path: impl AsRef<camino::Utf8Path>,
        flags: OpenFlags,
    ) -> Result<Self::File> {
        let path = path.as_ref();
        let c = format!(
            "While opening file {path:?} in a version {} archive",
            self.version
        );
        let mut tmp = crate::host::File::new()
            .wrap_err("While creating a temporary file")
            .wrap_err_with(|| c.clone())?;
        let mut created = false;

        {
            let mut archive = self.archive.lock();
            let mut trie = self.trie.write();

            if flags.contains(OpenFlags::Create) && !trie.contains_file(path) {
                created = true;
                match self.version {
                    1 | 2 => {
                        archive
                            .seek(SeekFrom::Start(8))
                            .wrap_err("While reading the header of the archive")
                            .wrap_err_with(|| c.clone())?;
                        let mut reader = BufReader::new(archive.as_file());
                        let mut magic = MAGIC;
                        let mut i = 0;
                        while let Ok(path_len) =
                            read_u32_xor(&mut reader, advance_magic(&mut magic))
                        {
                            for _ in 0..path_len {
                                advance_magic(&mut magic);
                            }
                            reader.seek(SeekFrom::Current(path_len as i64)).wrap_err_with(|| format!("While reading the file length (path length = {path_len}) of file #{i} in the archive")).wrap_err_with(|| c.clone())?;
                            let entry_len = read_u32_xor(&mut reader, advance_magic(&mut magic)).wrap_err_with(|| format!("While reading the file length (path length = {path_len}) of file #{i} in the archive")).wrap_err_with(|| c.clone())?;
                            reader.seek(SeekFrom::Current(entry_len as i64)).wrap_err_with(|| format!("While seeking forward by {entry_len} bytes to read file #{} in the archive", i + 1)).wrap_err_with(|| c.clone())?;
                            i += 1;
                        }
                        drop(reader);
                        regress_magic(&mut magic);

                        let archive_len = archive
                            .seek(SeekFrom::End(0))
                            .wrap_err(
                                "While writing the path length of the new file to the archive",
                            )
                            .wrap_err_with(|| c.clone())?;
                        let mut writer = BufWriter::new(archive.as_file());
                        writer
                            .write_all(
                                &(path.as_str().bytes().len() as u32 ^ advance_magic(&mut magic))
                                    .to_le_bytes(),
                            )
                            .wrap_err(
                                "While writing the path length of the new file to the archive",
                            )
                            .wrap_err_with(|| c.clone())?;
                        writer
                            .write_all(
                                &path
                                    .as_str()
                                    .bytes()
                                    .map(|b| {
                                        let b = if b == b'/' { b'\\' } else { b };
                                        b ^ advance_magic(&mut magic) as u8
                                    })
                                    .collect_vec(),
                            )
                            .wrap_err("While writing the path of the new file to the archive")
                            .wrap_err_with(|| c.clone())?;
                        writer
                            .write_all(&advance_magic(&mut magic).to_le_bytes())
                            .wrap_err(
                                "While writing the file length of the new file to the archive",
                            )
                            .wrap_err_with(|| c.clone())?;
                        writer
                            .flush()
                            .wrap_err("While flushing the archive after writing its contents")
                            .wrap_err_with(|| c.clone())?;
                        drop(writer);

                        trie.create_file(
                            path,
                            Entry {
                                header_offset: archive_len,
                                body_offset: archive_len + path.as_str().bytes().len() as u64 + 8,
                                size: 0,
                                start_magic: magic,
                            },
                        );
                    }

                    3 => {
                        let mut tmp = crate::host::File::new()
                            .wrap_err("While creating a temporary file")
                            .wrap_err_with(|| c.clone())?;

                        let extra_data_len = path.as_str().bytes().len() as u32 + 16;
                        let mut headers = Vec::new();

                        archive
                            .seek(SeekFrom::Start(12))
                            .wrap_err("While reading the header of the archive")
                            .wrap_err_with(|| c.clone())?;
                        let mut reader = BufReader::new(archive.as_file());
                        let mut position = 12;
                        let mut i = 0;
                        while let Ok(offset) = read_u32_xor(&mut reader, self.base_magic) {
                            if offset == 0 {
                                break;
                            }
                            headers.push((position, offset));
                            reader.seek(SeekFrom::Current(8)).wrap_err_with(|| format!("While reading the path length (file offset = {offset}) of file #{i} in the archive")).wrap_err_with(|| c.clone())?;
                            let path_len = read_u32_xor(&mut reader, self.base_magic).wrap_err_with(|| format!("While reading the path length (file offset = {offset}) of file #{i} in the archive")).wrap_err_with(|| c.clone())?;
                            position = reader.seek(SeekFrom::Current(path_len as i64)).wrap_err_with(|| format!("While seeking forward by {path_len} bytes to read file #{} in the archive", i + 1)).wrap_err_with(|| c.clone())?;
                            i += 1;
                        }
                        drop(reader);

                        archive
                            .seek(SeekFrom::Start(position))
                            .wrap_err("While copying the archive body into a temporary file")
                            .wrap_err_with(|| c.clone())?;
                        std::io::copy(archive.as_file(), &mut tmp)
                            .wrap_err("While copying the archive body into a temporary file")
                            .wrap_err_with(|| c.clone())?;
                        tmp.flush()
                            .wrap_err("While copying the archive body into a temporary file")
                            .wrap_err_with(|| c.clone())?;

                        let magic: u32 = rand::thread_rng().gen();
                        let archive_len = archive
                            .metadata()
                            .wrap_err("While getting the size of the archive")
                            .wrap_err_with(|| c.clone())?
                            .size as u32
                            + extra_data_len;
                        let mut writer = BufWriter::new(archive.as_file());
                        for (i, (position, offset)) in headers.into_iter().enumerate() {
                            writer
                                .seek(SeekFrom::Start(position))
                                .wrap_err_with(|| {
                                    format!("While rewriting the file offset of file #{i} to the archive")
                                })
                                .wrap_err_with(|| c.clone())?;
                            writer
                                .write_all(
                                    &((offset + extra_data_len) ^ self.base_magic).to_le_bytes(),
                                )
                                .wrap_err_with(|| {
                                    format!("While rewriting the file offset of file #{i} to the archive")
                                })
                                .wrap_err_with(|| c.clone())?;
                        }
                        writer
                            .seek(SeekFrom::Start(position))
                            .wrap_err(
                                "While writing the file offset of the new file to the archive",
                            )
                            .wrap_err_with(|| c.clone())?;
                        writer
                            .write_all(&(archive_len ^ self.base_magic).to_le_bytes())
                            .wrap_err(
                                "While writing the file offset of the new file to the archive",
                            )
                            .wrap_err_with(|| c.clone())?;
                        writer
                            .write_all(&self.base_magic.to_le_bytes())
                            .wrap_err(
                                "While writing the file length of the new file to the archive",
                            )
                            .wrap_err_with(|| c.clone())?;
                        writer
                            .write_all(&(magic ^ self.base_magic).to_le_bytes())
                            .wrap_err(
                                "While writing the base magic value of the new file to the archive",
                            )
                            .wrap_err_with(|| c.clone())?;
                        writer
                            .write_all(
                                &(path.as_str().bytes().len() as u32 ^ self.base_magic)
                                    .to_le_bytes(),
                            )
                            .wrap_err(
                                "While writing the path length of the new file to the archive",
                            )
                            .wrap_err_with(|| c.clone())?;
                        writer
                            .write_all(
                                &path
                                    .as_str()
                                    .bytes()
                                    .enumerate()
                                    .map(|(i, b)| {
                                        let b = if b == b'/' { b'\\' } else { b };
                                        b ^ (self.base_magic >> (8 * (i % 4))) as u8
                                    })
                                    .collect_vec(),
                            )
                            .wrap_err("While writing the path of the new file to the archive")
                            .wrap_err_with(|| c.clone())?;
                        tmp.seek(SeekFrom::Start(0)).wrap_err("While copying a temporary file containing the archive body into the archive").wrap_err_with(|| c.clone())?;
                        std::io::copy(&mut tmp, &mut writer).wrap_err("While copying a temporary file containing the archive body into the archive").wrap_err_with(|| c.clone())?;
                        writer.flush().wrap_err("While copying a temporary file containing the archive body into the archive").wrap_err_with(|| c.clone())?;
                        drop(writer);

                        trie.create_file(
                            path,
                            Entry {
                                header_offset: position,
                                body_offset: archive_len as u64,
                                size: 0,
                                start_magic: magic,
                            },
                        );
                    }

                    _ => return Err(Error::InvalidArchiveVersion(self.version).into()),
                }
            } else if !flags.contains(OpenFlags::Truncate) {
                let entry = *trie
                    .get_file(path)
                    .ok_or(Error::NotExist)
                    .wrap_err("While copying the file within the archive into a temporary file")
                    .wrap_err_with(|| c.clone())?;
                archive
                    .seek(SeekFrom::Start(entry.body_offset))
                    .wrap_err("While copying the file within the archive into a temporary file")
                    .wrap_err_with(|| c.clone())?;

                let mut adapter = BufReader::new(archive.as_file().take(entry.size));
                std::io::copy(
                    &mut read_file_xor(&mut adapter, entry.start_magic),
                    &mut tmp,
                )
                .wrap_err("While copying the file within the archive into a temporary file")
                .wrap_err_with(|| c.clone())?;
                tmp.flush()
                    .wrap_err("While copying the file within the archive into a temporary file")
                    .wrap_err_with(|| c.clone())?;
            } else if !trie.contains_file(path) {
                return Err(Error::NotExist.into());
            }
        }

        tmp.seek(SeekFrom::Start(0))
            .wrap_err("While copying the file within the archive into a temporary file")
            .wrap_err_with(|| c.clone())?;
        Ok(File {
            archive: flags
                .contains(OpenFlags::Write)
                .then(|| self.archive.clone()),
            trie: flags.contains(OpenFlags::Write).then(|| self.trie.clone()),
            path: path.to_owned(),
            read_allowed: flags.contains(OpenFlags::Read),
            tmp,
            modified: parking_lot::Mutex::new(
                !created && flags.contains(OpenFlags::Write) && flags.contains(OpenFlags::Truncate),
            ),
            version: self.version,
            base_magic: self.base_magic,
        })
    }

    fn metadata(&self, path: impl AsRef<camino::Utf8Path>) -> Result<Metadata> {
        let path = path.as_ref();
        let trie = self.trie.read();
        if let Some(entry) = trie.get_file(path) {
            Ok(Metadata {
                is_file: true,
                size: entry.size,
            })
        } else if let Some(size) = trie.get_dir_size(path) {
            Ok(Metadata {
                is_file: false,
                size: size as u64,
            })
        } else {
            Err(Error::NotExist.into())
        }
    }

    fn rename(
        &self,
        from: impl AsRef<camino::Utf8Path>,
        to: impl AsRef<camino::Utf8Path>,
    ) -> Result<()> {
        let from = from.as_ref();
        let to = to.as_ref();

        let mut archive = self.archive.lock();
        let mut trie = self.trie.write();
        let c = format!(
            "While renaming {from:?} to {to:?} in a version {} archive",
            self.version
        );

        if trie.contains_dir(from) {
            return Err(Error::NotSupported.into());
        }
        if trie.contains(to) {
            return Err(Error::IoError(AlreadyExists.into()).into());
        }
        if !trie.contains_dir(
            from.parent()
                .ok_or(Error::NotExist)
                .wrap_err_with(|| c.clone())?,
        ) {
            return Err(Error::NotExist.into());
        }
        let Some(old_entry) = trie.get_file(from).copied() else {
            return Err(Error::NotExist.into());
        };

        let archive_len = archive
            .metadata()
            .wrap_err("While getting the length of the archive")
            .wrap_err_with(|| c.clone())?
            .size;
        let from_len = from.as_str().bytes().len();
        let to_len = to.as_str().bytes().len();

        if from_len != to_len {
            match self.version {
                1 | 2 => {
                    // Move the file contents into a temporary file
                    let mut tmp = crate::host::File::new()
                        .wrap_err("While creating a temporary file")
                        .wrap_err_with(|| c.clone())?;
                    archive.seek(SeekFrom::Start(old_entry.body_offset)).wrap_err("While copying the contents of the file within the archive into a temporary file").wrap_err_with(|| c.clone())?;
                    let mut reader = BufReader::new(archive.as_file().take(old_entry.size));
                    std::io::copy(
                        &mut read_file_xor(&mut reader, old_entry.start_magic),
                        &mut tmp,
                    ).wrap_err("While copying the contents of the file within the archive into a temporary file").wrap_err_with(|| c.clone())?;
                    tmp.flush().wrap_err("While copying the contents of the file within the archive into a temporary file").wrap_err_with(|| c.clone())?;
                    drop(reader);

                    // Move the file to the end so that we can change the header size
                    move_file_and_truncate(
                        &mut archive,
                        &mut trie,
                        from,
                        self.version,
                        self.base_magic,
                    )
                    .wrap_err("While relocating the file header to the end of the archive")
                    .wrap_err_with(|| c.clone())?;
                    let mut new_entry = *trie
                        .get_file(from)
                        .ok_or(Error::InvalidHeader)
                        .wrap_err("While relocating the file header to the end of the archive")
                        .wrap_err_with(|| c.clone())?;
                    trie.remove_file(from)
                        .ok_or(Error::InvalidHeader)
                        .wrap_err("While relocating the file header to the end of the archive")
                        .wrap_err_with(|| c.clone())?;
                    new_entry.size = old_entry.size;

                    let mut magic = new_entry.start_magic;
                    regress_magic(&mut magic);
                    regress_magic(&mut magic);
                    for _ in from.as_str().bytes() {
                        regress_magic(&mut magic);
                    }

                    // Regenerate the header
                    archive
                        .seek(SeekFrom::Start(new_entry.header_offset))
                        .wrap_err("While rewriting the path length of the file to the archive")
                        .wrap_err_with(|| c.clone())?;
                    let mut writer = BufWriter::new(archive.as_file());
                    writer
                        .write_all(&(to_len as u32 ^ advance_magic(&mut magic)).to_le_bytes())
                        .wrap_err("While rewriting the path length of the file to the archive")
                        .wrap_err_with(|| c.clone())?;
                    writer
                        .write_all(
                            &to.as_str()
                                .bytes()
                                .map(|b| {
                                    let b = if b == b'/' { b'\\' } else { b };
                                    b ^ advance_magic(&mut magic) as u8
                                })
                                .collect_vec(),
                        )
                        .wrap_err("While rewriting the path of the file to the archive")
                        .wrap_err_with(|| c.clone())?;
                    writer
                        .write_all(
                            &(old_entry.size as u32 ^ advance_magic(&mut magic)).to_le_bytes(),
                        )
                        .wrap_err("While rewriting the file length of the file to the archive")
                        .wrap_err_with(|| c.clone())?;

                    new_entry.start_magic = magic;

                    // Move the file contents to the end
                    tmp.seek(SeekFrom::Start(0))
                        .wrap_err("While relocating the file contents to the end of the archive")
                        .wrap_err_with(|| c.clone())?;
                    let mut reader = BufReader::new(&mut tmp);
                    std::io::copy(&mut read_file_xor(&mut reader, magic), &mut writer)
                        .wrap_err("While relocating the file contents to the end of the archive")
                        .wrap_err_with(|| c.clone())?;
                    writer
                        .flush()
                        .wrap_err("While relocating the file contents to the end of the archive")
                        .wrap_err_with(|| c.clone())?;
                    drop(writer);

                    trie.create_file(to, new_entry);
                }

                3 => {
                    // Move everything after the header into a temporary file
                    let mut tmp = crate::host::File::new()
                        .wrap_err("While creating a temporary file")
                        .wrap_err_with(|| c.clone())?;
                    archive
                        .seek(SeekFrom::Start(
                            old_entry.header_offset + from_len as u64 + 16,
                        ))
                        .wrap_err("While copying the contents of the archive into a temporary file")
                        .wrap_err_with(|| c.clone())?;
                    std::io::copy(archive.as_file(), &mut tmp)
                        .wrap_err("While copying the contents of the archive into a temporary file")
                        .wrap_err_with(|| c.clone())?;
                    tmp.flush()
                        .wrap_err("While copying the contents of the archive into a temporary file")
                        .wrap_err_with(|| c.clone())?;

                    // Change the path
                    archive
                        .seek(SeekFrom::Start(old_entry.header_offset + 12))
                        .wrap_err("While rewriting the path length of the file to the archive")
                        .wrap_err_with(|| c.clone())?;
                    let mut writer = BufWriter::new(archive.as_file());
                    writer
                        .write_all(&(to_len as u32 ^ self.base_magic).to_le_bytes())
                        .wrap_err("While rewriting the path length of the file to the archive")
                        .wrap_err_with(|| c.clone())?;
                    writer
                        .write_all(
                            &to.as_str()
                                .bytes()
                                .enumerate()
                                .map(|(i, b)| {
                                    let b = if b == b'/' { b'\\' } else { b };
                                    b ^ (self.base_magic >> (8 * (i % 4))) as u8
                                })
                                .collect_vec(),
                        )
                        .wrap_err("While rewriting the path of the file to the archive")
                        .wrap_err_with(|| c.clone())?;
                    trie.remove_file(from)
                        .ok_or(Error::InvalidHeader)
                        .wrap_err("While rewriting the header of the file to the archive")
                        .wrap_err_with(|| c.clone())?;
                    trie.create_file(to, old_entry);

                    // Move everything else back
                    tmp.seek(SeekFrom::Start(0)).wrap_err("While copying a temporary file containing the archive body into the archive").wrap_err_with(|| c.clone())?;
                    std::io::copy(&mut tmp, &mut writer).wrap_err("While copying a temporary file containing the archive body into the archive").wrap_err_with(|| c.clone())?;
                    writer.flush().wrap_err("While copying a temporary file containing the archive body into the archive").wrap_err_with(|| c.clone())?;
                    drop(writer);

                    // Update all of the offsets in the headers
                    archive
                        .seek(SeekFrom::Start(12))
                        .wrap_err("While rewriting the header of the archive")
                        .wrap_err_with(|| c.clone())?;
                    let mut reader = BufReader::new(archive.as_file());
                    let mut headers = Vec::new();
                    let mut i = 0;
                    while let Ok(current_body_offset) = read_u32_xor(&mut reader, self.base_magic) {
                        if current_body_offset == 0 {
                            break;
                        }
                        let current_header_offset = reader
                            .stream_position()
                            .wrap_err_with(|| {
                                format!("While reading the path length of file #{i} in the archive")
                            })
                            .wrap_err_with(|| c.clone())?
                            .checked_sub(4)
                            .ok_or(Error::InvalidHeader)
                            .wrap_err_with(|| {
                                format!("While reading the path length of file #{i} in the archive")
                            })
                            .wrap_err_with(|| c.clone())?;
                        reader
                            .seek(SeekFrom::Current(8))
                            .wrap_err_with(|| {
                                format!("While reading the path length of file #{i} in the archive")
                            })
                            .wrap_err_with(|| c.clone())?;
                        let current_path_len = read_u32_xor(&mut reader, self.base_magic)
                            .wrap_err_with(|| {
                                format!("While reading the path length of file #{i} in the archive")
                            })
                            .wrap_err_with(|| c.clone())?;

                        let mut current_path = vec![0; current_path_len as usize];
                        reader.read_exact(&mut current_path).wrap_err_with(|| format!("While reading the path (path length = {current_path_len} of file #{i}) in the archive")).wrap_err_with(|| c.clone())?;
                        for (i, byte) in current_path.iter_mut().enumerate() {
                            let char = *byte ^ (self.base_magic >> (8 * (i % 4))) as u8;
                            if char == b'\\' {
                                *byte = b'/';
                            } else {
                                *byte = char;
                            }
                        }
                        let current_path =
                            String::from_utf8(current_path).map_err(|_| Error::PathUtf8Error).wrap_err_with(|| format!("While reading the path (path length = {current_path_len}) of file #{i} in the archive")).wrap_err_with(|| c.clone())?;

                        let current_body_offset = (current_body_offset as u64)
                            .checked_add_signed(to_len as i64 - from_len as i64)
                            .ok_or(Error::InvalidHeader)
                            .wrap_err_with(|| {
                                format!(
                                    "While reading the header (path = {current_path}) of file #{i} in the archive"
                                )
                            })
                            .wrap_err_with(|| c.clone())?;
                        trie.get_file_mut(&current_path)
                            .ok_or(Error::InvalidHeader)
                            .wrap_err_with(|| {
                                format!(
                                    "While reading the header (path = {current_path}) of file #{i} in the archive"
                                )
                            })
                            .wrap_err_with(|| c.clone())?
                            .body_offset = current_body_offset;
                        headers.push((current_header_offset, current_body_offset as u32));
                        i += 1;
                    }
                    drop(reader);
                    let mut writer = BufWriter::new(archive.as_file());
                    for (i, (position, offset)) in headers.into_iter().enumerate() {
                        writer.seek(SeekFrom::Start(position))?;
                        writer
                            .write_all(&(offset ^ self.base_magic).to_le_bytes())
                            .wrap_err_with(|| {
                                format!(
                                    "While rewriting the file offset of file #{i} to the archive"
                                )
                            })
                            .wrap_err_with(|| c.clone())?;
                    }
                    writer
                        .flush()
                        .wrap_err("While flushing the archive after writing its contents")
                        .wrap_err_with(|| c.clone())?;
                    drop(writer);
                }

                _ => return Err(Error::InvalidHeader.into()),
            }

            if to_len < from_len {
                archive.set_len(
                    archive_len
                        .checked_add_signed(to_len as i64 - from_len as i64)
                        .ok_or(Error::InvalidHeader)
                        .wrap_err("While truncating the archive")
                        .wrap_err_with(|| c.clone())?,
                )?;
                archive
                    .flush()
                    .wrap_err("While flushing the archive after writing its contents")
                    .wrap_err_with(|| c.clone())?;
            }
        } else {
            match self.version {
                1 | 2 => {
                    let mut magic = old_entry.start_magic;
                    for _ in from.as_str().bytes() {
                        regress_magic(&mut magic);
                    }
                    archive
                        .seek(SeekFrom::Start(old_entry.header_offset + 4))
                        .wrap_err("While rewriting the path of the file in-place to the archive")
                        .wrap_err_with(|| c.clone())?;
                    archive
                        .write_all(
                            &to.as_str()
                                .bytes()
                                .map(|b| {
                                    let b = if b == b'/' { b'\\' } else { b };
                                    b ^ advance_magic(&mut magic) as u8
                                })
                                .collect_vec(),
                        )
                        .wrap_err("While rewriting the path of the file in-place to the archive")
                        .wrap_err_with(|| c.clone())?;
                    archive
                        .flush()
                        .wrap_err("While rewriting the path of the file in-place to the archive")
                        .wrap_err_with(|| c.clone())?;
                }

                3 => {
                    archive
                        .seek(SeekFrom::Start(old_entry.header_offset + 16))
                        .wrap_err("While rewriting the path of the file in-place to the archive")
                        .wrap_err_with(|| c.clone())?;
                    archive
                        .write_all(
                            &to.as_str()
                                .bytes()
                                .enumerate()
                                .map(|(i, b)| {
                                    let b = if b == b'/' { b'\\' } else { b };
                                    b ^ (self.base_magic >> (8 * (i % 4))) as u8
                                })
                                .collect_vec(),
                        )
                        .wrap_err("While rewriting the path of the file in-place to the archive")
                        .wrap_err_with(|| c.clone())?;
                    archive
                        .flush()
                        .wrap_err("While rewriting the path of the file in-place to the archive")
                        .wrap_err_with(|| c.clone())?;
                }

                _ => return Err(Error::InvalidHeader.into()),
            }
        }

        Ok(())
    }

    fn create_dir(&self, path: impl AsRef<camino::Utf8Path>) -> Result<()> {
        let path = path.as_ref();
        let mut trie = self.trie.write();
        if trie.contains_file(path) {
            return Err(Error::IoError(AlreadyExists.into())).wrap_err_with(|| {
                format!(
                    "While creating a directory at {path:?} within a version {} archive",
                    self.version
                )
            });
        }
        trie.create_dir(path);
        Ok(())
    }

    fn exists(&self, path: impl AsRef<camino::Utf8Path>) -> Result<bool> {
        let trie = self.trie.read();
        Ok(trie.contains(path))
    }

    fn remove_dir(&self, path: impl AsRef<camino::Utf8Path>) -> Result<()> {
        let path = path.as_ref();
        let c = format!(
            "While removing a directory at {path:?} within a version {} archive",
            self.version
        );
        if !self.trie.read().contains_dir(path) {
            return Err(Error::NotExist).wrap_err_with(|| c.clone());
        }

        let paths = self
            .trie
            .read()
            .iter_prefix(path)
            .ok_or(Error::NotExist)
            .wrap_err_with(|| c.clone())?
            .map(|(k, _)| k)
            .collect_vec();
        for file_path in paths {
            self.remove_file(&file_path)
                .wrap_err_with(|| format!("While removing a file {file_path:?} within the archive"))
                .wrap_err_with(|| c.clone())?;
        }

        self.trie
            .write()
            .remove_dir(path)
            .then_some(())
            .ok_or(Error::NotExist)
            .wrap_err_with(|| c.clone())?;
        Ok(())
    }

    fn remove_file(&self, path: impl AsRef<camino::Utf8Path>) -> Result<()> {
        let path = path.as_ref();
        let path_len = path.as_str().bytes().len() as u64;
        let mut archive = self.archive.lock();
        let mut trie = self.trie.write();
        let c = format!(
            "While removing a file at {path:?} within a version {} archive",
            self.version
        );

        let entry = *trie
            .get_file(path)
            .ok_or(Error::NotExist)
            .wrap_err_with(|| c.clone())?;
        let archive_len = archive.metadata().wrap_err_with(|| c.clone())?.size;

        move_file_and_truncate(&mut archive, &mut trie, path, self.version, self.base_magic)
            .wrap_err("While relocating the file header to the end of the archive")
            .wrap_err_with(|| c.clone())?;

        match self.version {
            1 | 2 => {
                archive
                    .set_len(
                        archive_len
                            .checked_sub(entry.size + path_len + 8)
                            .ok_or(Error::IoError(InvalidData.into()))
                            .wrap_err("While truncating the archive")
                            .wrap_err_with(|| c.clone())?,
                    )
                    .wrap_err("While truncating the archive")
                    .wrap_err_with(|| c.clone())?;
                archive
                    .flush()
                    .wrap_err("While flushing the archive after writing its contents")
                    .wrap_err_with(|| c.clone())?;
            }

            3 => {
                // Remove the header of the deleted file
                let mut tmp = crate::host::File::new()
                    .wrap_err("While creating a temporary file")
                    .wrap_err_with(|| c.clone())?;
                archive
                    .seek(SeekFrom::Start(entry.header_offset + path_len + 16))
                    .wrap_err("While copying the header of the archive into a temporary file")
                    .wrap_err_with(|| c.clone())?;
                std::io::copy(archive.as_file(), &mut tmp)
                    .wrap_err("While copying the header of the archive into a temporary file")
                    .wrap_err_with(|| c.clone())?;
                tmp.flush()
                    .wrap_err("While copying the header of the archive into a temporary file")
                    .wrap_err_with(|| c.clone())?;
                tmp.seek(SeekFrom::Start(0)).wrap_err("While copying a temporary file containing the archive header into the archive").wrap_err_with(|| c.clone())?;
                archive.seek(SeekFrom::Start(entry.header_offset)).wrap_err("While copying a temporary file containing the archive header into the archive").wrap_err_with(|| c.clone())?;
                std::io::copy(&mut tmp, archive.as_file()).wrap_err("While copying a temporary file containing the archive header into the archive").wrap_err_with(|| c.clone())?;

                archive
                    .set_len(
                        archive_len
                            .checked_sub(entry.size + path_len + 16)
                            .ok_or(Error::IoError(InvalidData.into()))
                            .wrap_err("While truncating the archive")
                            .wrap_err_with(|| c.clone())?,
                    )
                    .wrap_err("While truncating the archive")
                    .wrap_err_with(|| c.clone())?;
                archive
                    .flush()
                    .wrap_err("While flushing the archive after writing its contents")
                    .wrap_err_with(|| c.clone())?;
            }

            _ => {
                return Err(Error::InvalidArchiveVersion(self.version)).wrap_err_with(|| c.clone())
            }
        }

        trie.remove_file(path);
        Ok(())
    }

    fn read_dir(&self, path: impl AsRef<camino::Utf8Path>) -> Result<Vec<DirEntry>> {
        let path = path.as_ref();
        let trie = self.trie.read();
        let c = format!(
            "While reading the contents of the directory {path:?} in a version {} archive",
            self.version
        );
        if let Some(iter) = trie.iter_dir(path) {
            iter.map(|(name, _)| {
                let path = if path == "" {
                    name.into()
                } else {
                    format!("{path}/{name}").into()
                };
                let metadata = self
                    .metadata(&path)
                    .wrap_err_with(|| {
                        format!("While getting the metadata of {path:?} in the archive")
                    })
                    .wrap_err_with(|| c.clone())?;
                Ok(DirEntry { path, metadata })
            })
            .try_collect()
        } else {
            Err(Error::NotExist).wrap_err_with(|| c.clone())
        }
    }
}