678 lines
20 KiB
Rust
678 lines
20 KiB
Rust
pub mod error;
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use crate::error::Error;
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use common::{OutputBuffer, ResourceData};
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use core::ops::Range;
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use std::cmp::Ordering;
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use std::fs::{self, OpenOptions as FsOpenOptions};
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use std::io::Write;
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use std::path::{Path, PathBuf};
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use std::sync::Arc;
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use std::time::{SystemTime, UNIX_EPOCH};
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pub type Result<T> = core::result::Result<T, Error>;
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#[derive(Clone, Debug, Default)]
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pub struct OpenOptions {
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pub raw_mode: bool,
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pub sequential_hint: bool,
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pub prefetch_pages: bool,
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}
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#[derive(Clone, Debug, Default)]
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pub enum OpenMode {
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#[default]
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ReadOnly,
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ReadWrite,
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}
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#[derive(Debug)]
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pub struct Archive {
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bytes: Arc<[u8]>,
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entries: Vec<EntryRecord>,
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raw_mode: bool,
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}
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#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
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pub struct EntryId(pub u32);
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#[derive(Clone, Debug)]
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pub struct EntryMeta {
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pub kind: u32,
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pub attr1: u32,
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pub attr2: u32,
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pub attr3: u32,
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pub name: String,
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pub data_offset: u64,
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pub data_size: u32,
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pub sort_index: u32,
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}
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#[derive(Copy, Clone, Debug)]
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pub struct EntryRef<'a> {
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pub id: EntryId,
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pub meta: &'a EntryMeta,
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}
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#[derive(Clone, Debug)]
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struct EntryRecord {
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meta: EntryMeta,
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name_raw: [u8; 36],
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}
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impl Archive {
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pub fn open_path(path: impl AsRef<Path>) -> Result<Self> {
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Self::open_path_with(path, OpenMode::ReadOnly, OpenOptions::default())
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}
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pub fn open_path_with(
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path: impl AsRef<Path>,
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_mode: OpenMode,
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opts: OpenOptions,
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) -> Result<Self> {
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let bytes = fs::read(path.as_ref())?;
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let arc: Arc<[u8]> = Arc::from(bytes.into_boxed_slice());
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Self::open_bytes(arc, opts)
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}
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pub fn open_bytes(bytes: Arc<[u8]>, opts: OpenOptions) -> Result<Self> {
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let (entries, _) = parse_archive(&bytes, opts.raw_mode)?;
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if opts.prefetch_pages {
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prefetch_pages(&bytes);
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}
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Ok(Self {
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bytes,
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entries,
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raw_mode: opts.raw_mode,
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})
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}
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pub fn entry_count(&self) -> usize {
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self.entries.len()
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}
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pub fn entries(&self) -> impl Iterator<Item = EntryRef<'_>> {
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self.entries
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.iter()
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.enumerate()
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.map(|(idx, entry)| EntryRef {
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id: EntryId(u32::try_from(idx).expect("entry count validated at parse")),
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meta: &entry.meta,
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})
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}
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pub fn find(&self, name: &str) -> Option<EntryId> {
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if self.entries.is_empty() {
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return None;
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}
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if !self.raw_mode {
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let mut low = 0usize;
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let mut high = self.entries.len();
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while low < high {
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let mid = low + (high - low) / 2;
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let Ok(target_idx) = usize::try_from(self.entries[mid].meta.sort_index) else {
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break;
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};
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if target_idx >= self.entries.len() {
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break;
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}
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let cmp = cmp_name_case_insensitive(
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name.as_bytes(),
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entry_name_bytes(&self.entries[target_idx].name_raw),
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);
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match cmp {
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Ordering::Less => high = mid,
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Ordering::Greater => low = mid + 1,
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Ordering::Equal => {
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return Some(EntryId(
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u32::try_from(target_idx).expect("entry count validated at parse"),
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))
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}
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}
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}
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}
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self.entries.iter().enumerate().find_map(|(idx, entry)| {
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if cmp_name_case_insensitive(name.as_bytes(), entry_name_bytes(&entry.name_raw))
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== Ordering::Equal
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{
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Some(EntryId(
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u32::try_from(idx).expect("entry count validated at parse"),
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))
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} else {
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None
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}
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})
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}
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pub fn get(&self, id: EntryId) -> Option<EntryRef<'_>> {
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let idx = usize::try_from(id.0).ok()?;
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let entry = self.entries.get(idx)?;
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Some(EntryRef {
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id,
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meta: &entry.meta,
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})
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}
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pub fn read(&self, id: EntryId) -> Result<ResourceData<'_>> {
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let range = self.entry_range(id)?;
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Ok(ResourceData::Borrowed(&self.bytes[range]))
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}
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pub fn read_into(&self, id: EntryId, out: &mut dyn OutputBuffer) -> Result<usize> {
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let range = self.entry_range(id)?;
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out.write_exact(&self.bytes[range.clone()])?;
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Ok(range.len())
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}
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pub fn raw_slice(&self, id: EntryId) -> Result<Option<&[u8]>> {
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let range = self.entry_range(id)?;
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Ok(Some(&self.bytes[range]))
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}
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pub fn edit_path(path: impl AsRef<Path>) -> Result<Editor> {
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let path_buf = path.as_ref().to_path_buf();
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let bytes = fs::read(&path_buf)?;
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let arc: Arc<[u8]> = Arc::from(bytes.into_boxed_slice());
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let (entries, _) = parse_archive(&arc, false)?;
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let mut editable = Vec::with_capacity(entries.len());
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for entry in &entries {
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let range = checked_range(entry.meta.data_offset, entry.meta.data_size, arc.len())?;
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editable.push(EditableEntry {
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meta: entry.meta.clone(),
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name_raw: entry.name_raw,
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data: EntryData::Borrowed(range), // Copy-on-write: only store range
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});
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}
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Ok(Editor {
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path: path_buf,
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source: arc,
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entries: editable,
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})
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}
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fn entry_range(&self, id: EntryId) -> Result<Range<usize>> {
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let idx = usize::try_from(id.0).map_err(|_| Error::IntegerOverflow)?;
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let Some(entry) = self.entries.get(idx) else {
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return Err(Error::EntryIdOutOfRange {
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id: id.0,
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entry_count: self.entries.len().try_into().unwrap_or(u32::MAX),
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});
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};
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checked_range(
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entry.meta.data_offset,
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entry.meta.data_size,
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self.bytes.len(),
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)
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}
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}
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pub struct Editor {
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path: PathBuf,
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source: Arc<[u8]>,
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entries: Vec<EditableEntry>,
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}
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#[derive(Clone, Debug)]
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enum EntryData {
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Borrowed(Range<usize>),
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Modified(Vec<u8>),
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}
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#[derive(Clone, Debug)]
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struct EditableEntry {
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meta: EntryMeta,
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name_raw: [u8; 36],
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data: EntryData,
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}
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impl EditableEntry {
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fn data_slice<'a>(&'a self, source: &'a Arc<[u8]>) -> &'a [u8] {
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match &self.data {
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EntryData::Borrowed(range) => &source[range.clone()],
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EntryData::Modified(vec) => vec.as_slice(),
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}
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}
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}
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#[derive(Clone, Debug)]
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pub struct NewEntry<'a> {
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pub kind: u32,
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pub attr1: u32,
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pub attr2: u32,
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pub attr3: u32,
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pub name: &'a str,
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pub data: &'a [u8],
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}
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impl Editor {
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pub fn entries(&self) -> impl Iterator<Item = EntryRef<'_>> {
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self.entries
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.iter()
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.enumerate()
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.map(|(idx, entry)| EntryRef {
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id: EntryId(u32::try_from(idx).expect("entry count validated at add")),
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meta: &entry.meta,
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})
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}
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pub fn add(&mut self, entry: NewEntry<'_>) -> Result<EntryId> {
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let name_raw = encode_name_field(entry.name)?;
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let id_u32 = u32::try_from(self.entries.len()).map_err(|_| Error::IntegerOverflow)?;
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let data_size = u32::try_from(entry.data.len()).map_err(|_| Error::IntegerOverflow)?;
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self.entries.push(EditableEntry {
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meta: EntryMeta {
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kind: entry.kind,
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attr1: entry.attr1,
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attr2: entry.attr2,
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attr3: entry.attr3,
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name: decode_name(entry_name_bytes(&name_raw)),
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data_offset: 0,
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data_size,
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sort_index: 0,
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},
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name_raw,
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data: EntryData::Modified(entry.data.to_vec()),
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});
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Ok(EntryId(id_u32))
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}
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pub fn replace_data(&mut self, id: EntryId, data: &[u8]) -> Result<()> {
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let idx = usize::try_from(id.0).map_err(|_| Error::IntegerOverflow)?;
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let Some(entry) = self.entries.get_mut(idx) else {
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return Err(Error::EntryIdOutOfRange {
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id: id.0,
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entry_count: self.entries.len().try_into().unwrap_or(u32::MAX),
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});
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};
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entry.meta.data_size = u32::try_from(data.len()).map_err(|_| Error::IntegerOverflow)?;
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// Replace with new data (triggers copy-on-write if borrowed)
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entry.data = EntryData::Modified(data.to_vec());
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Ok(())
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}
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pub fn remove(&mut self, id: EntryId) -> Result<()> {
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let idx = usize::try_from(id.0).map_err(|_| Error::IntegerOverflow)?;
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if idx >= self.entries.len() {
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return Err(Error::EntryIdOutOfRange {
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id: id.0,
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entry_count: self.entries.len().try_into().unwrap_or(u32::MAX),
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});
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}
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self.entries.remove(idx);
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Ok(())
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}
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pub fn commit(mut self) -> Result<()> {
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let count_u32 = u32::try_from(self.entries.len()).map_err(|_| Error::IntegerOverflow)?;
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// Pre-calculate capacity to avoid reallocations
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let total_data_size: usize = self
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.entries
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.iter()
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.map(|e| e.data_slice(&self.source).len())
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.sum();
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let padding_estimate = self.entries.len() * 8; // Max 8 bytes padding per entry
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let directory_size = self.entries.len() * 64; // 64 bytes per entry
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let capacity = 16 + total_data_size + padding_estimate + directory_size;
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let mut out = Vec::with_capacity(capacity);
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out.resize(16, 0); // Header
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// Keep reference to source for copy-on-write
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let source = &self.source;
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for entry in &mut self.entries {
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entry.meta.data_offset =
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u64::try_from(out.len()).map_err(|_| Error::IntegerOverflow)?;
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// Calculate size and get slice separately to avoid borrow conflicts
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let data_len = entry.data_slice(source).len();
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entry.meta.data_size = u32::try_from(data_len).map_err(|_| Error::IntegerOverflow)?;
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// Now get the slice again for writing
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let data_slice = entry.data_slice(source);
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out.extend_from_slice(data_slice);
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let padding = (8 - (out.len() % 8)) % 8;
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if padding > 0 {
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out.resize(out.len() + padding, 0);
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}
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}
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let mut sort_order: Vec<usize> = (0..self.entries.len()).collect();
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sort_order.sort_by(|a, b| {
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cmp_name_case_insensitive(
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entry_name_bytes(&self.entries[*a].name_raw),
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entry_name_bytes(&self.entries[*b].name_raw),
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)
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});
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for (idx, entry) in self.entries.iter_mut().enumerate() {
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entry.meta.sort_index =
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u32::try_from(sort_order[idx]).map_err(|_| Error::IntegerOverflow)?;
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}
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for entry in &self.entries {
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let data_offset_u32 =
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u32::try_from(entry.meta.data_offset).map_err(|_| Error::IntegerOverflow)?;
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push_u32(&mut out, entry.meta.kind);
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push_u32(&mut out, entry.meta.attr1);
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push_u32(&mut out, entry.meta.attr2);
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push_u32(&mut out, entry.meta.data_size);
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push_u32(&mut out, entry.meta.attr3);
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out.extend_from_slice(&entry.name_raw);
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push_u32(&mut out, data_offset_u32);
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push_u32(&mut out, entry.meta.sort_index);
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}
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let total_size_u32 = u32::try_from(out.len()).map_err(|_| Error::IntegerOverflow)?;
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out[0..4].copy_from_slice(b"NRes");
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out[4..8].copy_from_slice(&0x100_u32.to_le_bytes());
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out[8..12].copy_from_slice(&count_u32.to_le_bytes());
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out[12..16].copy_from_slice(&total_size_u32.to_le_bytes());
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write_atomic(&self.path, &out)
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}
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}
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fn parse_archive(bytes: &[u8], raw_mode: bool) -> Result<(Vec<EntryRecord>, u64)> {
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if raw_mode {
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let data_size = u32::try_from(bytes.len()).map_err(|_| Error::IntegerOverflow)?;
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let entry = EntryRecord {
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meta: EntryMeta {
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kind: 0,
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attr1: 0,
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attr2: 0,
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attr3: 0,
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name: String::from("RAW"),
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data_offset: 0,
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data_size,
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sort_index: 0,
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},
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name_raw: {
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let mut name = [0u8; 36];
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let bytes_name = b"RAW";
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name[..bytes_name.len()].copy_from_slice(bytes_name);
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name
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},
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};
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return Ok((
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vec![entry],
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u64::try_from(bytes.len()).map_err(|_| Error::IntegerOverflow)?,
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));
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}
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if bytes.len() < 16 {
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let mut got = [0u8; 4];
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let copy_len = bytes.len().min(4);
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got[..copy_len].copy_from_slice(&bytes[..copy_len]);
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return Err(Error::InvalidMagic { got });
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}
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let mut magic = [0u8; 4];
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magic.copy_from_slice(&bytes[0..4]);
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if &magic != b"NRes" {
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return Err(Error::InvalidMagic { got: magic });
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}
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let version = read_u32(bytes, 4)?;
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if version != 0x100 {
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return Err(Error::UnsupportedVersion { got: version });
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}
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let entry_count_i32 = i32::from_le_bytes(
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bytes[8..12]
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.try_into()
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.map_err(|_| Error::IntegerOverflow)?,
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);
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if entry_count_i32 < 0 {
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return Err(Error::InvalidEntryCount {
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got: entry_count_i32,
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});
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}
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let entry_count = usize::try_from(entry_count_i32).map_err(|_| Error::IntegerOverflow)?;
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// Validate entry_count fits in u32 (required for EntryId)
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if entry_count > u32::MAX as usize {
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return Err(Error::TooManyEntries { got: entry_count });
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}
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let total_size = read_u32(bytes, 12)?;
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let actual_size = u64::try_from(bytes.len()).map_err(|_| Error::IntegerOverflow)?;
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if u64::from(total_size) != actual_size {
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return Err(Error::TotalSizeMismatch {
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header: total_size,
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actual: actual_size,
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});
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}
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let directory_len = u64::try_from(entry_count)
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.map_err(|_| Error::IntegerOverflow)?
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.checked_mul(64)
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.ok_or(Error::IntegerOverflow)?;
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let directory_offset =
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u64::from(total_size)
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.checked_sub(directory_len)
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.ok_or(Error::DirectoryOutOfBounds {
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directory_offset: 0,
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directory_len,
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file_len: actual_size,
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})?;
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if directory_offset < 16 || directory_offset + directory_len > actual_size {
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return Err(Error::DirectoryOutOfBounds {
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directory_offset,
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directory_len,
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file_len: actual_size,
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});
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}
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let mut entries = Vec::with_capacity(entry_count);
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for index in 0..entry_count {
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let base = usize::try_from(directory_offset)
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.map_err(|_| Error::IntegerOverflow)?
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.checked_add(index.checked_mul(64).ok_or(Error::IntegerOverflow)?)
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.ok_or(Error::IntegerOverflow)?;
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let kind = read_u32(bytes, base)?;
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let attr1 = read_u32(bytes, base + 4)?;
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let attr2 = read_u32(bytes, base + 8)?;
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let data_size = read_u32(bytes, base + 12)?;
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let attr3 = read_u32(bytes, base + 16)?;
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let mut name_raw = [0u8; 36];
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let name_slice = bytes
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.get(base + 20..base + 56)
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.ok_or(Error::IntegerOverflow)?;
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name_raw.copy_from_slice(name_slice);
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let name_bytes = entry_name_bytes(&name_raw);
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if name_bytes.len() > 35 {
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return Err(Error::NameTooLong {
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got: name_bytes.len(),
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max: 35,
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});
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}
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let data_offset = u64::from(read_u32(bytes, base + 56)?);
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let sort_index = read_u32(bytes, base + 60)?;
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let end = data_offset
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.checked_add(u64::from(data_size))
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.ok_or(Error::IntegerOverflow)?;
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if data_offset < 16 || end > directory_offset {
|
|
return Err(Error::EntryDataOutOfBounds {
|
|
id: u32::try_from(index).map_err(|_| Error::IntegerOverflow)?,
|
|
offset: data_offset,
|
|
size: data_size,
|
|
directory_offset,
|
|
});
|
|
}
|
|
|
|
entries.push(EntryRecord {
|
|
meta: EntryMeta {
|
|
kind,
|
|
attr1,
|
|
attr2,
|
|
attr3,
|
|
name: decode_name(name_bytes),
|
|
data_offset,
|
|
data_size,
|
|
sort_index,
|
|
},
|
|
name_raw,
|
|
});
|
|
}
|
|
|
|
Ok((entries, directory_offset))
|
|
}
|
|
|
|
fn checked_range(offset: u64, size: u32, bytes_len: usize) -> Result<Range<usize>> {
|
|
let start = usize::try_from(offset).map_err(|_| Error::IntegerOverflow)?;
|
|
let len = usize::try_from(size).map_err(|_| Error::IntegerOverflow)?;
|
|
let end = start.checked_add(len).ok_or(Error::IntegerOverflow)?;
|
|
if end > bytes_len {
|
|
return Err(Error::IntegerOverflow);
|
|
}
|
|
Ok(start..end)
|
|
}
|
|
|
|
fn read_u32(bytes: &[u8], offset: usize) -> Result<u32> {
|
|
let data = bytes
|
|
.get(offset..offset + 4)
|
|
.ok_or(Error::IntegerOverflow)?;
|
|
let arr: [u8; 4] = data.try_into().map_err(|_| Error::IntegerOverflow)?;
|
|
Ok(u32::from_le_bytes(arr))
|
|
}
|
|
|
|
fn push_u32(out: &mut Vec<u8>, value: u32) {
|
|
out.extend_from_slice(&value.to_le_bytes());
|
|
}
|
|
|
|
fn encode_name_field(name: &str) -> Result<[u8; 36]> {
|
|
let bytes = name.as_bytes();
|
|
if bytes.contains(&0) {
|
|
return Err(Error::NameContainsNul);
|
|
}
|
|
if bytes.len() > 35 {
|
|
return Err(Error::NameTooLong {
|
|
got: bytes.len(),
|
|
max: 35,
|
|
});
|
|
}
|
|
|
|
let mut out = [0u8; 36];
|
|
out[..bytes.len()].copy_from_slice(bytes);
|
|
Ok(out)
|
|
}
|
|
|
|
fn entry_name_bytes(raw: &[u8; 36]) -> &[u8] {
|
|
let len = raw.iter().position(|&b| b == 0).unwrap_or(raw.len());
|
|
&raw[..len]
|
|
}
|
|
|
|
fn decode_name(name: &[u8]) -> String {
|
|
name.iter().map(|b| char::from(*b)).collect()
|
|
}
|
|
|
|
fn cmp_name_case_insensitive(a: &[u8], b: &[u8]) -> Ordering {
|
|
let mut idx = 0usize;
|
|
let min_len = a.len().min(b.len());
|
|
while idx < min_len {
|
|
let left = ascii_lower(a[idx]);
|
|
let right = ascii_lower(b[idx]);
|
|
if left != right {
|
|
return left.cmp(&right);
|
|
}
|
|
idx += 1;
|
|
}
|
|
a.len().cmp(&b.len())
|
|
}
|
|
|
|
fn ascii_lower(value: u8) -> u8 {
|
|
if value.is_ascii_uppercase() {
|
|
value + 32
|
|
} else {
|
|
value
|
|
}
|
|
}
|
|
|
|
fn prefetch_pages(bytes: &[u8]) {
|
|
use std::sync::atomic::{compiler_fence, Ordering};
|
|
|
|
let mut cursor = 0usize;
|
|
let mut sink = 0u8;
|
|
while cursor < bytes.len() {
|
|
sink ^= bytes[cursor];
|
|
cursor = cursor.saturating_add(4096);
|
|
}
|
|
compiler_fence(Ordering::SeqCst);
|
|
let _ = sink;
|
|
}
|
|
|
|
fn write_atomic(path: &Path, content: &[u8]) -> Result<()> {
|
|
let file_name = path
|
|
.file_name()
|
|
.and_then(|name| name.to_str())
|
|
.unwrap_or("archive");
|
|
let parent = path.parent().unwrap_or_else(|| Path::new("."));
|
|
|
|
let mut temp_path = None;
|
|
for attempt in 0..128u32 {
|
|
let name = format!(
|
|
".{}.tmp.{}.{}.{}",
|
|
file_name,
|
|
std::process::id(),
|
|
unix_time_nanos(),
|
|
attempt
|
|
);
|
|
let candidate = parent.join(name);
|
|
let opened = FsOpenOptions::new()
|
|
.create_new(true)
|
|
.write(true)
|
|
.open(&candidate);
|
|
if let Ok(mut file) = opened {
|
|
file.write_all(content)?;
|
|
file.sync_all()?;
|
|
temp_path = Some((candidate, file));
|
|
break;
|
|
}
|
|
}
|
|
|
|
let Some((tmp_path, mut file)) = temp_path else {
|
|
return Err(Error::Io(std::io::Error::new(
|
|
std::io::ErrorKind::AlreadyExists,
|
|
"failed to create temporary file for atomic write",
|
|
)));
|
|
};
|
|
|
|
file.flush()?;
|
|
drop(file);
|
|
|
|
match fs::rename(&tmp_path, path) {
|
|
Ok(()) => Ok(()),
|
|
Err(rename_err) => {
|
|
if path.exists() {
|
|
fs::remove_file(path)?;
|
|
fs::rename(&tmp_path, path)?;
|
|
Ok(())
|
|
} else {
|
|
let _ = fs::remove_file(&tmp_path);
|
|
Err(Error::Io(rename_err))
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
fn unix_time_nanos() -> u128 {
|
|
match SystemTime::now().duration_since(UNIX_EPOCH) {
|
|
Ok(duration) => duration.as_nanos(),
|
|
Err(_) => 0,
|
|
}
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests;
|