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authorValentin Popov <valentin@popov.link>2024-07-19 15:37:58 +0300
committerValentin Popov <valentin@popov.link>2024-07-19 15:37:58 +0300
commita990de90fe41456a23e58bd087d2f107d321f3a1 (patch)
tree15afc392522a9e85dc3332235e311b7d39352ea9 /vendor/object/src/read/read_cache.rs
parent3d48cd3f81164bbfc1a755dc1d4a9a02f98c8ddd (diff)
downloadfparkan-a990de90fe41456a23e58bd087d2f107d321f3a1.tar.xz
fparkan-a990de90fe41456a23e58bd087d2f107d321f3a1.zip
Deleted vendor folder
Diffstat (limited to 'vendor/object/src/read/read_cache.rs')
-rw-r--r--vendor/object/src/read/read_cache.rs178
1 files changed, 0 insertions, 178 deletions
diff --git a/vendor/object/src/read/read_cache.rs b/vendor/object/src/read/read_cache.rs
deleted file mode 100644
index d1377f1..0000000
--- a/vendor/object/src/read/read_cache.rs
+++ /dev/null
@@ -1,178 +0,0 @@
-use core::ops::Range;
-use std::boxed::Box;
-use std::cell::RefCell;
-use std::collections::hash_map::Entry;
-use std::collections::HashMap;
-use std::convert::TryInto;
-use std::io::{Read, Seek, SeekFrom};
-use std::mem;
-use std::vec::Vec;
-
-use crate::read::ReadRef;
-
-/// An implementation of [`ReadRef`] for data in a stream that implements
-/// `Read + Seek`.
-///
-/// Contains a cache of read-only blocks of data, allowing references to
-/// them to be returned. Entries in the cache are never removed.
-/// Entries are keyed on the offset and size of the read.
-/// Currently overlapping reads are considered separate reads.
-#[derive(Debug)]
-pub struct ReadCache<R: Read + Seek> {
- cache: RefCell<ReadCacheInternal<R>>,
-}
-
-#[derive(Debug)]
-struct ReadCacheInternal<R: Read + Seek> {
- read: R,
- bufs: HashMap<(u64, u64), Box<[u8]>>,
- strings: HashMap<(u64, u8), Box<[u8]>>,
-}
-
-impl<R: Read + Seek> ReadCache<R> {
- /// Create an empty `ReadCache` for the given stream.
- pub fn new(read: R) -> Self {
- ReadCache {
- cache: RefCell::new(ReadCacheInternal {
- read,
- bufs: HashMap::new(),
- strings: HashMap::new(),
- }),
- }
- }
-
- /// Return an implementation of `ReadRef` that restricts reads
- /// to the given range of the stream.
- pub fn range(&self, offset: u64, size: u64) -> ReadCacheRange<'_, R> {
- ReadCacheRange {
- r: self,
- offset,
- size,
- }
- }
-
- /// Free buffers used by the cache.
- pub fn clear(&mut self) {
- self.cache.borrow_mut().bufs.clear();
- }
-
- /// Unwrap this `ReadCache<R>`, returning the underlying reader.
- pub fn into_inner(self) -> R {
- self.cache.into_inner().read
- }
-}
-
-impl<'a, R: Read + Seek> ReadRef<'a> for &'a ReadCache<R> {
- fn len(self) -> Result<u64, ()> {
- let cache = &mut *self.cache.borrow_mut();
- cache.read.seek(SeekFrom::End(0)).map_err(|_| ())
- }
-
- fn read_bytes_at(self, offset: u64, size: u64) -> Result<&'a [u8], ()> {
- if size == 0 {
- return Ok(&[]);
- }
- let cache = &mut *self.cache.borrow_mut();
- let buf = match cache.bufs.entry((offset, size)) {
- Entry::Occupied(entry) => entry.into_mut(),
- Entry::Vacant(entry) => {
- let size = size.try_into().map_err(|_| ())?;
- cache.read.seek(SeekFrom::Start(offset)).map_err(|_| ())?;
- let mut bytes = vec![0; size].into_boxed_slice();
- cache.read.read_exact(&mut bytes).map_err(|_| ())?;
- entry.insert(bytes)
- }
- };
- // Extend the lifetime to that of self.
- // This is OK because we never mutate or remove entries.
- Ok(unsafe { mem::transmute::<&[u8], &[u8]>(buf) })
- }
-
- fn read_bytes_at_until(self, range: Range<u64>, delimiter: u8) -> Result<&'a [u8], ()> {
- let cache = &mut *self.cache.borrow_mut();
- let buf = match cache.strings.entry((range.start, delimiter)) {
- Entry::Occupied(entry) => entry.into_mut(),
- Entry::Vacant(entry) => {
- cache
- .read
- .seek(SeekFrom::Start(range.start))
- .map_err(|_| ())?;
-
- let max_check: usize = (range.end - range.start).try_into().map_err(|_| ())?;
- // Strings should be relatively small.
- // TODO: make this configurable?
- let max_check = max_check.min(4096);
-
- let mut bytes = Vec::new();
- let mut checked = 0;
- loop {
- bytes.resize((checked + 256).min(max_check), 0);
- let read = cache.read.read(&mut bytes[checked..]).map_err(|_| ())?;
- if read == 0 {
- return Err(());
- }
- if let Some(len) = memchr::memchr(delimiter, &bytes[checked..][..read]) {
- bytes.truncate(checked + len);
- break entry.insert(bytes.into_boxed_slice());
- }
- checked += read;
- if checked >= max_check {
- return Err(());
- }
- }
- }
- };
- // Extend the lifetime to that of self.
- // This is OK because we never mutate or remove entries.
- Ok(unsafe { mem::transmute::<&[u8], &[u8]>(buf) })
- }
-}
-
-/// An implementation of [`ReadRef`] for a range of data in a stream that
-/// implements `Read + Seek`.
-///
-/// Shares an underlying `ReadCache` with a lifetime of `'a`.
-#[derive(Debug)]
-pub struct ReadCacheRange<'a, R: Read + Seek> {
- r: &'a ReadCache<R>,
- offset: u64,
- size: u64,
-}
-
-impl<'a, R: Read + Seek> Clone for ReadCacheRange<'a, R> {
- fn clone(&self) -> Self {
- *self
- }
-}
-
-impl<'a, R: Read + Seek> Copy for ReadCacheRange<'a, R> {}
-
-impl<'a, R: Read + Seek> ReadRef<'a> for ReadCacheRange<'a, R> {
- fn len(self) -> Result<u64, ()> {
- Ok(self.size)
- }
-
- fn read_bytes_at(self, offset: u64, size: u64) -> Result<&'a [u8], ()> {
- if size == 0 {
- return Ok(&[]);
- }
- let end = offset.checked_add(size).ok_or(())?;
- if end > self.size {
- return Err(());
- }
- let r_offset = self.offset.checked_add(offset).ok_or(())?;
- self.r.read_bytes_at(r_offset, size)
- }
-
- fn read_bytes_at_until(self, range: Range<u64>, delimiter: u8) -> Result<&'a [u8], ()> {
- let r_start = self.offset.checked_add(range.start).ok_or(())?;
- let r_end = self.offset.checked_add(range.end).ok_or(())?;
- let bytes = self.r.read_bytes_at_until(r_start..r_end, delimiter)?;
- let size = bytes.len().try_into().map_err(|_| ())?;
- let end = range.start.checked_add(size).ok_or(())?;
- if end > self.size {
- return Err(());
- }
- Ok(bytes)
- }
-}