Matthew Jackson
8000bae177
Test-hardening release, no runtime changes. Adds spec-grounded unit tests across the silent-corruption surfaces — UDF/MPLS/CLPI/IFO parsing, BD/DVD title + extent assembly, AACS/CSS key handling, TS/PS demux + codec parsers, MKV/EBML container output, the mux pipeline, sector prefetch + decrypt decorator, drive/SCSI sense decoding, label extraction, and core I/O. Each test is grounded in the format spec or real on-disc behavior and verified to fail under a targeted source mutation. No behavior changed.
1214 lines
50 KiB
Rust
1214 lines
50 KiB
Rust
//! `PrefetchedSectorSource` — runs the wrapped read+decrypt in a
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//! dedicated producer thread and surfaces the prepared plaintext
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//! buffers on demand via a bounded channel.
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//!
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//! ## Why
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//!
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//! The mux consumer (demux + codec parsing + frame output) is
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//! single-threaded by nature (streams are sequential). The mux
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//! producer (read sectors + AACS decrypt) is also single-threaded
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//! per-call but does CPU-heavy work (AES per 6144-byte unit). Running
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//! both on the same thread means the disk and decrypt cores sit idle
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//! while the demux runs, and vice versa.
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//!
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//! Splitting them across two threads with a bounded channel between
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//! lets both run in parallel — peak throughput becomes
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//! `min(producer_rate, consumer_rate)` instead of
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//! `1 / (1/producer + 1/consumer)`.
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//!
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//! ## Lifecycle
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//!
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//! The producer thread is spawned by [`PrefetchedSectorSource::new`]
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//! (which returns `Err` if the OS refuses the thread spawn).
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//! It walks the supplied extent list in order, reads the configured
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//! batch size at each LBA, and sends the resulting plaintext buffer
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//! into a [`crossbeam_channel::bounded`] channel of small depth (so
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//! the producer stays a couple of batches ahead without unbounded
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//! memory growth).
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//!
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//! When the channel sender drops (either because all extents were
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//! served or because the [`Halt`] token cancelled), the consumer
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//! observes `RecvError` on the next `read_sectors` and treats it as
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//! end-of-stream. Errors from the underlying reader are forwarded
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//! verbatim through the channel.
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//!
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//! ## Read API
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//!
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//! `read_sectors` ignores its `lba`/`count` arguments — the producer
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//! has already chosen what to read, in the order the extents dictate.
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//! This is sound for the mux read path, which always walks extents
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//! sequentially and never seeks. For random-access callers (sweep
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//! patch retries) this wrapper is the wrong tool — they should keep
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//! reading the underlying source directly.
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use crate::error::Result;
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use crate::event::{Event, EventKind};
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use crate::halt::Halt;
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use crate::sector::SectorSource;
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use crossbeam_channel::{Receiver, Sender, bounded};
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use std::thread::JoinHandle;
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/// Producer-thread event callback. Fires `BytesRead` after every
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/// successful batch read so the consumer side can update a UI
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/// progress indicator without polling. `Send + 'static` because the
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/// callback runs on the producer thread.
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pub type EventFn = Box<dyn Fn(Event) + Send + 'static>;
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const PREFETCH_CHANNEL_DEPTH: usize = 2;
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/// Smallest sector source the producer will issue per read. AACS
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/// alignment requires multiples of 3 sectors so a unit doesn't span
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/// two reads.
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const SECTOR_ALIGNMENT: u16 = 3;
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/// Item flowing through the prefetch forward channel.
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pub type Batch = std::result::Result<Vec<u8>, std::io::Error>;
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/// Producer-thread-backed [`SectorSource`] decorator. Construct it
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/// with the real reader, the extent list to walk, and the batch
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/// size; the wrapper spawns the producer immediately and starts
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/// filling the channel.
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pub struct PrefetchedSectorSource {
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rx: Receiver<Batch>,
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/// Recycle channel — consumer returns drained buffers here; the
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/// producer re-fills them in place. Lets the producer/consumer
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/// reuse a fixed pool of `PREFETCH_CHANNEL_DEPTH+1` buffers
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/// instead of `Vec::new()`-ing one per batch (musl mallocng
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/// cross-thread alloc/free was the dominant cost in the demux
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/// thread before this).
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recycle_tx: Sender<Vec<u8>>,
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/// Joined on drop so producer cleanup runs deterministically.
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producer: Option<JoinHandle<()>>,
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/// Total sector count across all extents, computed once at
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/// construction (the sum of each extent's `sector_count`) and
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/// returned by [`capacity_sectors`]. Never updated by reads.
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///
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/// [`capacity_sectors`]: SectorSource::capacity_sectors
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total_sectors: u32,
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}
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impl PrefetchedSectorSource {
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/// Spawn the producer thread. `reader` must already be the fully
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/// composed read+decrypt stack (e.g.
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/// [`DecryptingSectorSource`](crate::sector::DecryptingSectorSource))
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/// — every byte the producer emits is what the consumer's demux
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/// will feed to its codec parsers.
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///
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/// ## Unit-alignment precondition
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///
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/// Each extent's `sector_count` should be a multiple of
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/// [`SECTOR_ALIGNMENT`] (3 sectors / one 6144-byte AACS aligned
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/// unit). Blu-ray m2ts extents satisfy this by spec. If an extent
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/// has a trailing 1-2 sectors that cannot fill a complete unit,
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/// the producer surfaces [`Error::ExtentNotUnitAligned`] through
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/// the channel rather than handing the decrypt step a sub-unit
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/// chunk it would silently leave encrypted.
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///
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/// [`Error::ExtentNotUnitAligned`]: crate::error::Error::ExtentNotUnitAligned
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pub fn new<S>(
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reader: S,
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extents: Vec<crate::disc::Extent>,
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batch_sectors: u16,
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halt: Option<Halt>,
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) -> Result<Self>
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where
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S: SectorSource + Send + 'static,
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{
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Self::new_with_events(reader, extents, batch_sectors, halt, None)
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}
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/// Same as [`new`] but with a callback fired from the producer
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/// thread after each successful batch — used by autorip's mux
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/// path to surface `BytesRead` progress to the UI without the
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/// consumer thread having to poll.
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pub fn new_with_events<S>(
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mut reader: S,
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extents: Vec<crate::disc::Extent>,
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batch_sectors: u16,
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halt: Option<Halt>,
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event_fn: Option<EventFn>,
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) -> Result<Self>
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where
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S: SectorSource + Send + 'static,
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{
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// A zero batch would make the producer loop forever emitting
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// empty batches (sectors = remaining.min(0) = 0, offset never
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// advances). All production callers pass a nonzero constant; a
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// public-API caller passing 0 is a programming error, so reject
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// it rather than spin a thread that never makes progress.
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if batch_sectors == 0 {
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return Err(crate::error::Error::IoError {
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source: std::io::Error::from(std::io::ErrorKind::InvalidInput),
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});
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}
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// Accumulate in u64 then clamp: extents can derive from
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// untrusted nav/MPLS/UDF data, so a naive u32 `sum()` could
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// panic in debug / wrap in release on a hostile total. The
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// clamp only affects the advisory `capacity_sectors` figure;
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// the producer walks each extent independently below.
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let total_sectors: u32 = extents
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.iter()
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.map(|e| e.sector_count as u64)
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.sum::<u64>()
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.min(u32::MAX as u64) as u32;
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let bytes_total_extents: u64 = extents.iter().map(|e| e.sector_count as u64 * 2048).sum();
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let (tx, rx) = bounded::<Batch>(PREFETCH_CHANNEL_DEPTH);
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let (recycle_tx, recycle_rx) = bounded::<Vec<u8>>(PREFETCH_CHANNEL_DEPTH + 1);
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let batch_bytes = batch_sectors as usize * 2048;
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// Seed the recycle pool so the producer always has a buffer
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// to fill on the first iteration. Without these, the first
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// `recycle_rx.recv()` would block forever (no consumer has
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// returned a buffer yet).
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for _ in 0..(PREFETCH_CHANNEL_DEPTH + 1) {
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let _ = recycle_tx.send(vec![0u8; batch_bytes]);
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}
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let producer = std::thread::Builder::new()
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.name("freemkv-prefetch".into())
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.spawn(move || {
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let mut ext_idx = 0usize;
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let mut offset: u32 = 0;
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let mut bytes_read_total: u64 = 0;
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while ext_idx < extents.len() {
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if halt.as_ref().map(|h| h.is_cancelled()).unwrap_or(false) {
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return;
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}
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let extent = &extents[ext_idx];
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let remaining = extent.sector_count.saturating_sub(offset);
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if remaining == 0 {
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ext_idx += 1;
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offset = 0;
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continue;
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}
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// The AACS aligned unit is SECTOR_ALIGNMENT (3)
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// sectors / 6144 bytes; the decrypt step only
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// processes full units and silently leaves a
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// shorter trailing chunk encrypted. So a batch must
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// be a whole number of units — except for the final
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// batch of an extent whose `sector_count` is itself
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// unit-aligned (then the remaining tail is exactly
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// 0 mod 3 and forms full units on its own).
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//
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// If the trailing sectors of this extent cannot fill
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// a complete unit (`remaining < SECTOR_ALIGNMENT`
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// with nothing more to read, or a 1-2 sector
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// leftover after the last full unit), there is no
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// way to hand the decrypt step an aligned chunk —
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// surface a typed error instead of emitting
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// still-encrypted bytes.
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if remaining % SECTOR_ALIGNMENT as u32 != 0
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&& remaining < SECTOR_ALIGNMENT as u32
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{
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let _ = tx.send(Err(crate::error::Error::ExtentNotUnitAligned.into()));
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return;
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}
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let mut sectors = remaining.min(batch_sectors as u32) as u16;
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// Trim to a whole number of units. Once trimmed to 0
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// here it means `remaining >= SECTOR_ALIGNMENT` but
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// the *batch window* landed on a sub-unit boundary —
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// never the trailing-tail case, which the guard
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// above already rejected. Clamp to one unit so we
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// always make forward progress.
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if sectors >= SECTOR_ALIGNMENT {
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sectors -= sectors % SECTOR_ALIGNMENT;
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} else {
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sectors = SECTOR_ALIGNMENT;
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}
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let bytes = sectors as usize * 2048;
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let mut buf = match recycle_rx.recv() {
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Ok(b) => b,
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Err(_) => return, // consumer dropped both channels
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};
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if bytes <= buf.capacity() {
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// Re-expose `bytes` without zero-filling pages that
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// `read_sectors` is about to overwrite. The enclosing
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// capacity guard makes the `set_len` provably sound even
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// if a recycled buffer ever comes back smaller than the
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// `vec![0u8; batch_bytes]` it was born with.
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debug_assert!(bytes <= buf.capacity(), "set_len exceeds capacity");
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unsafe { buf.set_len(bytes) };
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} else {
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buf.resize(bytes, 0);
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}
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// `start_lba + offset` derives from untrusted extent
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// data — saturate rather than wrap/panic on a
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// hostile start_lba near u32::MAX.
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let lba = extent.start_lba.saturating_add(offset);
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match reader.read_sectors(lba, sectors, &mut buf[..bytes], false) {
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Ok(n) => {
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// A short read must not silently desync the
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// stream: advance the extent cursor by the
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// sectors actually read, not the requested
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// count, and reject a byte count that isn't a
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// whole number of sectors (it would split a
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// sector and leave the decrypt step a partial
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// unit). The sole production inner source
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// (FileSectorSource) read_exact's the full
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// request, so this is belt-and-braces against
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// a future short-reading source.
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if n % 2048 != 0 {
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let _ =
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tx.send(Err(crate::error::Error::ExtentNotUnitAligned.into()));
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return;
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}
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let sectors_read = (n / 2048) as u32;
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buf.truncate(n);
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bytes_read_total = bytes_read_total.saturating_add(n as u64);
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if let Some(ref f) = event_fn {
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f(Event {
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kind: EventKind::BytesRead {
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bytes: bytes_read_total,
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total: bytes_total_extents,
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},
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});
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}
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if tx.send(Ok(buf)).is_err() {
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return; // consumer dropped
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}
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// A genuine zero-byte read with no error would
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// otherwise spin this loop forever; treat it
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// as end-of-source.
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if sectors_read == 0 {
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return;
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}
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offset = offset.saturating_add(sectors_read);
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}
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Err(e) => {
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let _ = tx.send(Err(e.into()));
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return;
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}
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}
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}
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// Drop tx implicitly — consumer sees RecvError → EOF.
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})
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.map_err(|e| crate::error::Error::IoError { source: e })?;
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Ok(Self {
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rx,
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recycle_tx,
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producer: Some(producer),
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total_sectors,
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})
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}
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/// Peel off the receivers for zero-copy pipeline mode. The
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/// caller (typically [`super::super::mux::demux_thread::DemuxThread`])
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/// pulls buffers from `rx`, consumes them, and pushes the empty
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/// `Vec<u8>` back through `recycle_tx` so the producer can
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/// re-fill it. The producer-thread `JoinHandle` stays with the
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/// returned `PrefetchedSectorSource` shell; drop that to join.
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///
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/// Returns `(forward_rx, recycle_tx, shell)`. The shell only
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/// holds the join handle and total_sectors for `capacity_sectors`
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/// queries; its `SectorSource` impl becomes invalid after this
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/// call (data has been moved out).
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pub fn into_channels(self) -> (Receiver<Batch>, Sender<Vec<u8>>, PrefetchShell) {
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// MOVE the three fields out cleanly — never clone. Each of
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// `rx` and `recycle_tx` ends up with exactly ONE live copy:
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// the one in the returned tuple. The pre-1.0.0 implementation
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// cloned both and then `mem::forget`-ed `self`, leaking the
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// originals so an extra live receiver + sender survived
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// forever. That defeated the channel-disconnection shutdown:
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// when the demux consumer exited early (halt, or a `tx.send`
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// error in `demux_thread`), the producer's `recycle_rx.recv()`
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// and `tx.send()` never saw all-peers-dropped, so the producer
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// never returned and `PrefetchShell::drop`'s `join()` hung.
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//
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// `ManuallyDrop` + `ptr::read` reads each field out by value
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// and suppresses `self`'s own `Drop` (which would otherwise
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// double-`join`), leaving NO extra live endpoint behind. This
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// is the panic-free equivalent of the `Option::take` approach.
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let total = self.total_sectors;
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let me = std::mem::ManuallyDrop::new(self);
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// SAFETY: `me` is `ManuallyDrop`, so none of these fields will
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// be dropped by `me`. Each `ptr::read` performs exactly one
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// bitwise move out; every field is read exactly once and never
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// touched again, so there are no double-frees and no aliasing.
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let producer = unsafe { std::ptr::read(&me.producer) };
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let rx = unsafe { std::ptr::read(&me.rx) };
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let recycle = unsafe { std::ptr::read(&me.recycle_tx) };
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(rx, recycle, PrefetchShell { producer, total })
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}
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}
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/// Returned from [`PrefetchedSectorSource::into_channels`]. Owns the
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/// producer thread join handle so dropping the shell joins the
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/// producer, even though the channels have been peeled off.
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pub struct PrefetchShell {
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producer: Option<JoinHandle<()>>,
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#[allow(dead_code)]
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total: u32,
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}
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impl Drop for PrefetchShell {
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fn drop(&mut self) {
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if let Some(h) = self.producer.take() {
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let _ = h.join();
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}
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}
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}
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impl Drop for PrefetchedSectorSource {
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fn drop(&mut self) {
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// Dropping the receiver closes the channel, which makes the
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// next producer `send` return Err and exits the loop. Joining
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// here gives us a deterministic shutdown — no detached thread
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// can outlive the source.
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if let Some(h) = self.producer.take() {
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let _ = h.join();
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}
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}
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}
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impl SectorSource for PrefetchedSectorSource {
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fn capacity_sectors(&self) -> u32 {
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self.total_sectors
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}
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fn read_sectors(
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&mut self,
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_lba: u32,
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_count: u16,
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buf: &mut [u8],
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_recovery: bool,
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) -> Result<usize> {
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// The producer has already decided the next batch. lba/count
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// are advisory; the consumer's fill_extents will advance its
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// own bookkeeping using the returned byte count, not the
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// requested count.
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match self.rx.recv() {
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Ok(Ok(filled)) => {
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// Precondition: the caller's buffer must be large
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// enough to hold the producer's batch. If it is not we
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// would silently drop `filled[buf.len()..]`, desyncing
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// the stream. The production zero-copy path never uses
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// this method (it consumes the channel directly via
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// `into_channels`), so a too-small buffer here is a
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// caller bug — surface it instead of corrupting data.
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if filled.len() > buf.len() {
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return Err(crate::error::Error::IoError {
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source: std::io::Error::from(std::io::ErrorKind::InvalidInput),
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});
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}
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let n = filled.len();
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buf[..n].copy_from_slice(&filled[..n]);
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// Return the buffer to the recycle pool so the producer
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// can re-fill it. Without this the pool (seeded with
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// PREFETCH_CHANNEL_DEPTH+1 buffers) drains after that
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// many reads and the producer blocks forever on
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// `recycle_rx.recv()` while the consumer blocks on the
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// next `rx.recv()` — a permanent deadlock. The
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// `into_channels` zero-copy path recycles explicitly;
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// this direct-read path must do the same.
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let _ = self.recycle_tx.send(filled);
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Ok(n)
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}
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Ok(Err(e)) => Err(crate::error::Error::IoError { source: e }),
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// Channel closed (producer finished or panicked).
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Err(_) => Ok(0),
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}
|
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}
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}
|
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|
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#[cfg(test)]
|
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mod tests {
|
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use super::*;
|
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use crate::disc::Extent;
|
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use crate::error::Result;
|
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use std::sync::mpsc;
|
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use std::time::Duration;
|
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|
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/// Endless zero-yielding source: every read succeeds, so the
|
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/// producer keeps trying to push batches forward until the forward
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/// channel disconnects. Exactly the shape that wedged the pre-1.0.0
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/// `clone + mem::forget` `into_channels`.
|
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struct EndlessZeroSource;
|
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impl SectorSource for EndlessZeroSource {
|
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fn read_sectors(
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&mut self,
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_lba: u32,
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count: u16,
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buf: &mut [u8],
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_recovery: bool,
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) -> Result<usize> {
|
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let bytes = count as usize * 2048;
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buf[..bytes].fill(0);
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Ok(bytes)
|
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}
|
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}
|
|
|
|
/// Synthetic source that fills `buf` with a per-sector byte
|
|
/// pattern derived from the LBA, always satisfying the full
|
|
/// request (mirrors `FileSectorSource`'s read_exact contract).
|
|
struct PatternSource {
|
|
capacity: u32,
|
|
}
|
|
|
|
impl SectorSource for PatternSource {
|
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fn capacity_sectors(&self) -> u32 {
|
|
self.capacity
|
|
}
|
|
|
|
fn read_sectors(
|
|
&mut self,
|
|
lba: u32,
|
|
count: u16,
|
|
buf: &mut [u8],
|
|
_recovery: bool,
|
|
) -> Result<usize> {
|
|
let bytes = count as usize * 2048;
|
|
for s in 0..count as usize {
|
|
let base = s * 2048;
|
|
let tag = (lba.wrapping_add(s as u32) & 0xff) as u8;
|
|
for b in &mut buf[base..base + 2048] {
|
|
*b = tag;
|
|
}
|
|
}
|
|
Ok(bytes)
|
|
}
|
|
}
|
|
|
|
/// Source that returns a short read (fewer sectors than
|
|
/// requested) on its very first call, then full reads. Used to
|
|
/// prove the producer advances by sectors actually read.
|
|
struct ShortFirstSource {
|
|
capacity: u32,
|
|
first: bool,
|
|
}
|
|
|
|
impl SectorSource for ShortFirstSource {
|
|
fn capacity_sectors(&self) -> u32 {
|
|
self.capacity
|
|
}
|
|
|
|
fn read_sectors(
|
|
&mut self,
|
|
lba: u32,
|
|
count: u16,
|
|
buf: &mut [u8],
|
|
_recovery: bool,
|
|
) -> Result<usize> {
|
|
let give = if self.first {
|
|
self.first = false;
|
|
// Short read: hand back one aligned unit (3 sectors)
|
|
// regardless of the larger request.
|
|
SECTOR_ALIGNMENT.min(count)
|
|
} else {
|
|
count
|
|
};
|
|
let bytes = give as usize * 2048;
|
|
for s in 0..give as usize {
|
|
let base = s * 2048;
|
|
let tag = (lba.wrapping_add(s as u32) & 0xff) as u8;
|
|
for b in &mut buf[base..base + 2048] {
|
|
*b = tag;
|
|
}
|
|
}
|
|
Ok(bytes)
|
|
}
|
|
}
|
|
|
|
fn big_extent() -> Vec<Extent> {
|
|
// One huge extent so the producer never reaches EOF on its own;
|
|
// the only way it can exit is by observing channel disconnection.
|
|
vec![Extent {
|
|
start_lba: 0,
|
|
sector_count: u32::MAX,
|
|
}]
|
|
}
|
|
|
|
/// Run `f` on a helper thread and fail if it does not finish within
|
|
/// `secs`. Used to turn a join-deadlock into a test failure instead
|
|
/// of a hung CI run.
|
|
fn within<F: FnOnce() + Send + 'static>(secs: u64, f: F) {
|
|
let (done_tx, done_rx) = bounded::<()>(1);
|
|
std::thread::spawn(move || {
|
|
f();
|
|
let _ = done_tx.send(());
|
|
});
|
|
assert!(
|
|
done_rx
|
|
.recv_timeout(std::time::Duration::from_secs(secs))
|
|
.is_ok(),
|
|
"operation did not complete within {secs}s (deadlock)"
|
|
);
|
|
}
|
|
|
|
/// Run `f` on a worker thread; fail (rather than hang) if it does
|
|
/// not finish within `timeout`. Guards the deadlock regression so
|
|
/// a reintroduced bug fails the suite instead of wedging it.
|
|
fn with_watchdog<F>(timeout: Duration, f: F)
|
|
where
|
|
F: FnOnce() + Send + 'static,
|
|
{
|
|
let (done_tx, done_rx) = mpsc::channel::<()>();
|
|
let h = std::thread::spawn(move || {
|
|
f();
|
|
let _ = done_tx.send(());
|
|
});
|
|
match done_rx.recv_timeout(timeout) {
|
|
Ok(()) => {
|
|
let _ = h.join();
|
|
}
|
|
Err(_) => panic!("watchdog timeout — likely deadlock/hang in prefetch read path"),
|
|
}
|
|
}
|
|
|
|
/// The CRITICAL regression: after `into_channels`, dropping the
|
|
/// returned forward receiver + recycle sender must let the producer
|
|
/// observe disconnection and exit, so dropping the `PrefetchShell`
|
|
/// (which joins the producer) returns promptly. With the old
|
|
/// clone+forget the leaked endpoints kept the producer blocked and
|
|
/// this join hung forever.
|
|
#[test]
|
|
fn into_channels_drop_releases_producer() {
|
|
within(10, || {
|
|
let src = PrefetchedSectorSource::new(EndlessZeroSource, big_extent(), 3, None)
|
|
.expect("spawn");
|
|
let (rx, recycle_tx, shell) = src.into_channels();
|
|
// Consumer goes away early (halt / abort analogue): drop both
|
|
// channel endpoints without draining to EOF.
|
|
drop(rx);
|
|
drop(recycle_tx);
|
|
// Joining the producer must not hang.
|
|
drop(shell);
|
|
});
|
|
}
|
|
|
|
/// Same property via the halt path: cancel the token, then the
|
|
/// producer must exit and the shell join must complete.
|
|
///
|
|
/// The producer parks in a BLOCKING `tx.send` on the forward channel
|
|
/// and only checks `halt` at the loop top, so `halt.cancel()` cannot
|
|
/// interrupt a send that is already blocked on a full channel. To
|
|
/// keep the test deterministic under load, we drain the forward
|
|
/// receiver on a background thread: every send then makes progress,
|
|
/// the producer reaches the loop top, observes the cancelled halt,
|
|
/// and exits — so the shell join completes promptly regardless of
|
|
/// scheduling. (Channel-disconnection shutdown is covered separately
|
|
/// by `into_channels_drop_releases_producer`.)
|
|
#[test]
|
|
fn halt_releases_producer() {
|
|
within(10, || {
|
|
let halt = Halt::new();
|
|
let src =
|
|
PrefetchedSectorSource::new(EndlessZeroSource, big_extent(), 3, Some(halt.clone()))
|
|
.expect("spawn");
|
|
let (rx, recycle_tx, shell) = src.into_channels();
|
|
// Drain the forward channel so the producer's sends always
|
|
// make progress and it can reach the halt check at the loop
|
|
// top, recycling buffers so it never blocks on the pool.
|
|
let drainer = std::thread::spawn(move || {
|
|
while let Ok(item) = rx.recv() {
|
|
if let Ok(buf) = item {
|
|
let _ = recycle_tx.send(buf);
|
|
}
|
|
}
|
|
});
|
|
halt.cancel();
|
|
drop(shell);
|
|
let _ = drainer.join();
|
|
});
|
|
}
|
|
|
|
/// `batch_sectors == 0` is rejected rather than spawning a thread
|
|
/// that spins forever emitting empty batches.
|
|
#[test]
|
|
fn zero_batch_rejected() {
|
|
let err = PrefetchedSectorSource::new(EndlessZeroSource, big_extent(), 0, None);
|
|
assert!(err.is_err(), "zero batch_sectors must be rejected");
|
|
}
|
|
|
|
/// >3 sequential direct `read_sectors` calls must succeed. The
|
|
/// recycle pool seeds PREFETCH_CHANNEL_DEPTH+1 (3) buffers; before
|
|
/// the fix the direct path dropped each drained buffer, so the 4th
|
|
/// call deadlocked. Watchdog-guarded.
|
|
#[test]
|
|
fn direct_reads_past_pool_depth_do_not_deadlock() {
|
|
with_watchdog(Duration::from_secs(10), || {
|
|
// 24 sectors = 8 aligned units; batch of 3 sectors gives 8
|
|
// sequential batches, well past the 3-buffer pool depth.
|
|
let extents = vec![Extent {
|
|
start_lba: 0,
|
|
sector_count: 24,
|
|
}];
|
|
let src = PatternSource { capacity: 24 };
|
|
let mut pf = PrefetchedSectorSource::new(src, extents, 3, None).expect("spawn");
|
|
|
|
let mut buf = vec![0u8; 3 * 2048];
|
|
let mut total = 0usize;
|
|
for _ in 0..16 {
|
|
let n = pf.read_sectors(0, 3, &mut buf, false).unwrap();
|
|
if n == 0 {
|
|
break; // EOF
|
|
}
|
|
total += n;
|
|
}
|
|
assert_eq!(total, 24 * 2048, "all 24 sectors should be drained");
|
|
});
|
|
}
|
|
|
|
/// An extent whose sector_count is not a multiple of 3 must not
|
|
/// emit a still-encrypted sub-unit tail. The producer delivers the
|
|
/// readable full units, then surfaces a typed error on the tail
|
|
/// instead of a short batch. Watchdog-guarded so a regression that
|
|
/// hangs (rather than errors) still fails.
|
|
#[test]
|
|
fn non_multiple_of_three_extent_errors_on_tail() {
|
|
with_watchdog(Duration::from_secs(10), || {
|
|
// 8 sectors = 2 full units (6 sectors) + 2 leftover.
|
|
let extents = vec![Extent {
|
|
start_lba: 100,
|
|
sector_count: 8,
|
|
}];
|
|
let src = PatternSource { capacity: 200 };
|
|
let mut pf = PrefetchedSectorSource::new(src, extents, 3, None).expect("spawn");
|
|
|
|
let mut buf = vec![0u8; 3 * 2048];
|
|
// First two reads: the 6 unit-aligned sectors come through
|
|
// as full 3-sector (6144-byte) batches.
|
|
let n0 = pf.read_sectors(0, 3, &mut buf, false).unwrap();
|
|
assert_eq!(n0, 3 * 2048);
|
|
let n1 = pf.read_sectors(0, 3, &mut buf, false).unwrap();
|
|
assert_eq!(n1, 3 * 2048);
|
|
// Third read hits the 2-sector tail: it must be an error,
|
|
// never a 4096-byte (sub-unit) batch that decrypt would
|
|
// leave encrypted.
|
|
let err = pf.read_sectors(0, 3, &mut buf, false);
|
|
assert!(
|
|
err.is_err(),
|
|
"non-unit-aligned tail must error, got Ok({:?})",
|
|
err
|
|
);
|
|
});
|
|
}
|
|
|
|
/// A short read (inner source returns fewer sectors than
|
|
/// requested) must advance the extent cursor by the sectors
|
|
/// actually read, not the requested count — otherwise the bytes
|
|
/// between the short read and the request size are silently
|
|
/// skipped. We verify every sector of the extent is delivered.
|
|
#[test]
|
|
fn short_read_does_not_desync_stream() {
|
|
with_watchdog(Duration::from_secs(10), || {
|
|
// 9 sectors = 3 full units. batch of 9 means the first
|
|
// request is for 9 sectors; ShortFirstSource hands back
|
|
// only 3, so the producer must re-request the remaining 6.
|
|
let extents = vec![Extent {
|
|
start_lba: 0,
|
|
sector_count: 9,
|
|
}];
|
|
let src = ShortFirstSource {
|
|
capacity: 9,
|
|
first: true,
|
|
};
|
|
let mut pf = PrefetchedSectorSource::new(src, extents, 9, None).expect("spawn");
|
|
|
|
let mut buf = vec![0u8; 9 * 2048];
|
|
let mut total = 0usize;
|
|
for _ in 0..16 {
|
|
let n = pf.read_sectors(0, 9, &mut buf, false).unwrap();
|
|
if n == 0 {
|
|
break;
|
|
}
|
|
total += n;
|
|
}
|
|
assert_eq!(
|
|
total,
|
|
9 * 2048,
|
|
"short read must not drop sectors; all 9 must be delivered"
|
|
);
|
|
});
|
|
}
|
|
|
|
// ---------------------------------------------------------------
|
|
// Additional coverage below.
|
|
// ---------------------------------------------------------------
|
|
|
|
use std::sync::{Arc, Mutex};
|
|
|
|
/// Records every (lba, count) the producer issued, in order, and
|
|
/// always satisfies the full request. Lets a test assert the exact
|
|
/// read schedule (LBA walk, batch sizing, unit trimming).
|
|
struct RecordingSource {
|
|
capacity: u32,
|
|
calls: Arc<Mutex<Vec<(u32, u16)>>>,
|
|
}
|
|
impl SectorSource for RecordingSource {
|
|
fn capacity_sectors(&self) -> u32 {
|
|
self.capacity
|
|
}
|
|
fn read_sectors(
|
|
&mut self,
|
|
lba: u32,
|
|
count: u16,
|
|
buf: &mut [u8],
|
|
_recovery: bool,
|
|
) -> Result<usize> {
|
|
self.calls.lock().unwrap().push((lba, count));
|
|
let bytes = count as usize * 2048;
|
|
buf[..bytes].fill((lba & 0xff) as u8);
|
|
Ok(bytes)
|
|
}
|
|
}
|
|
|
|
/// Always returns a typed I/O error on the first read. Verifies the
|
|
/// producer forwards the underlying error verbatim through the
|
|
/// channel instead of swallowing it / treating it as EOF.
|
|
struct ErrorSource;
|
|
impl SectorSource for ErrorSource {
|
|
fn read_sectors(
|
|
&mut self,
|
|
_lba: u32,
|
|
_count: u16,
|
|
_buf: &mut [u8],
|
|
_recovery: bool,
|
|
) -> Result<usize> {
|
|
Err(crate::error::Error::IoError {
|
|
source: std::io::Error::from(std::io::ErrorKind::PermissionDenied),
|
|
})
|
|
}
|
|
}
|
|
|
|
/// Returns a byte count that is NOT a whole number of sectors
|
|
/// (n % 2048 != 0). The producer must reject this as a split-sector
|
|
/// short read rather than truncate-and-advance into a partial unit.
|
|
struct PartialSectorSource;
|
|
impl SectorSource for PartialSectorSource {
|
|
fn read_sectors(
|
|
&mut self,
|
|
_lba: u32,
|
|
_count: u16,
|
|
buf: &mut [u8],
|
|
_recovery: bool,
|
|
) -> Result<usize> {
|
|
// One sector plus 100 bytes — never a multiple of 2048.
|
|
let n = 2048 + 100;
|
|
buf[..n].fill(0xab);
|
|
Ok(n)
|
|
}
|
|
}
|
|
|
|
/// Drains a prefetch source via the direct `read_sectors` API into a
|
|
/// single contiguous Vec, stopping at the first EOF (Ok(0)) or the
|
|
/// first error. Returns (bytes, last_result).
|
|
fn drain_direct(
|
|
pf: &mut PrefetchedSectorSource,
|
|
buf_sectors: u16,
|
|
max_iters: usize,
|
|
) -> (Vec<u8>, Result<usize>) {
|
|
let mut buf = vec![0u8; buf_sectors as usize * 2048];
|
|
let mut out = Vec::new();
|
|
let mut last: Result<usize> = Ok(0);
|
|
for _ in 0..max_iters {
|
|
let r = pf.read_sectors(0, buf_sectors, &mut buf, false);
|
|
match r {
|
|
Ok(0) => {
|
|
last = Ok(0);
|
|
break;
|
|
}
|
|
Ok(n) => {
|
|
out.extend_from_slice(&buf[..n]);
|
|
last = Ok(n);
|
|
}
|
|
Err(e) => {
|
|
last = Err(e);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
(out, last)
|
|
}
|
|
|
|
/// `capacity_sectors` returns the sum of all extents' sector_counts,
|
|
/// computed once at construction. Grounding: doc comment on
|
|
/// `total_sectors` — "the sum of each extent's sector_count".
|
|
#[test]
|
|
fn capacity_sectors_sums_all_extents() {
|
|
with_watchdog(Duration::from_secs(10), || {
|
|
let extents = vec![
|
|
Extent {
|
|
start_lba: 0,
|
|
sector_count: 9,
|
|
},
|
|
Extent {
|
|
start_lba: 100,
|
|
sector_count: 6,
|
|
},
|
|
Extent {
|
|
start_lba: 500,
|
|
sector_count: 3,
|
|
},
|
|
];
|
|
let src = PatternSource { capacity: 9999 };
|
|
let pf = PrefetchedSectorSource::new(src, extents, 3, None).expect("spawn");
|
|
// 9 + 6 + 3 = 18, independent of inner source capacity.
|
|
assert_eq!(pf.capacity_sectors(), 18);
|
|
// Release the producer without draining: peel the channels
|
|
// and drop them so the producer observes disconnection
|
|
// (dropping `pf` directly would join while still holding the
|
|
// channels → deadlock; the production drain path always uses
|
|
// into_channels).
|
|
let (rx, recycle_tx, shell) = pf.into_channels();
|
|
drop(rx);
|
|
drop(recycle_tx);
|
|
drop(shell);
|
|
});
|
|
}
|
|
|
|
/// Total-sector accumulation must clamp at u32::MAX rather than
|
|
/// panic (debug overflow) or wrap (release) on a hostile extent set
|
|
/// whose summed sector_count exceeds u32. Grounding: the `new`
|
|
/// comment — "Accumulate in u64 then clamp ... a naive u32 sum()
|
|
/// could panic in debug / wrap in release".
|
|
#[test]
|
|
fn capacity_sectors_clamps_on_overflow() {
|
|
with_watchdog(Duration::from_secs(10), || {
|
|
let extents = vec![
|
|
Extent {
|
|
start_lba: 0,
|
|
sector_count: u32::MAX,
|
|
},
|
|
Extent {
|
|
start_lba: 0,
|
|
sector_count: u32::MAX,
|
|
},
|
|
];
|
|
// batch=3 so the producer makes forward progress on the
|
|
// EndlessZeroSource; we only care about the construction-time
|
|
// capacity computation here, then we drop to join.
|
|
let pf =
|
|
PrefetchedSectorSource::new(EndlessZeroSource, extents, 3, None).expect("spawn");
|
|
assert_eq!(
|
|
pf.capacity_sectors(),
|
|
u32::MAX,
|
|
"summed total must saturate at u32::MAX, not wrap"
|
|
);
|
|
// Release the producer via into_channels + drop (a direct
|
|
// drop of `pf` would join while still holding the channels →
|
|
// deadlock against the still-running EndlessZeroSource).
|
|
let (rx, recycle_tx, shell) = pf.into_channels();
|
|
drop(rx);
|
|
drop(recycle_tx);
|
|
drop(shell);
|
|
});
|
|
}
|
|
|
|
/// The producer must walk extents in list order and start each
|
|
/// extent at its `start_lba` (plus running offset within the
|
|
/// extent), never reorder or merge them. Grounding: lifecycle doc
|
|
/// — "walks the supplied extent list in order" and
|
|
/// `lba = extent.start_lba.saturating_add(offset)`.
|
|
#[test]
|
|
fn producer_walks_extents_in_order_at_correct_lbas() {
|
|
with_watchdog(Duration::from_secs(10), || {
|
|
let calls = Arc::new(Mutex::new(Vec::new()));
|
|
let extents = vec![
|
|
Extent {
|
|
start_lba: 1000,
|
|
sector_count: 6, // two 3-sector batches
|
|
},
|
|
Extent {
|
|
start_lba: 50,
|
|
sector_count: 3, // one batch — lower LBA, MUST stay second
|
|
},
|
|
];
|
|
let src = RecordingSource {
|
|
capacity: 99999,
|
|
calls: calls.clone(),
|
|
};
|
|
let mut pf = PrefetchedSectorSource::new(src, extents, 3, None).expect("spawn");
|
|
let (got, last) = drain_direct(&mut pf, 3, 16);
|
|
assert_eq!(last.unwrap(), 0, "should reach EOF");
|
|
assert_eq!(got.len(), (6 + 3) * 2048);
|
|
drop(pf);
|
|
let recorded = calls.lock().unwrap().clone();
|
|
// Expect: extent0 at 1000 then 1003 (offset+3), then extent1 at 50.
|
|
assert_eq!(
|
|
recorded,
|
|
vec![(1000, 3), (1003, 3), (50, 3)],
|
|
"extents must be walked in list order at their start_lba+offset"
|
|
);
|
|
});
|
|
}
|
|
|
|
/// A batch larger than one unit must be trimmed DOWN to a whole
|
|
/// number of 3-sector units before issuing the read — never a
|
|
/// sub-unit count that decrypt would leave partially encrypted.
|
|
/// batch=5 → trimmed to 3 (5 - 5%3). Grounding: the unit-trim block
|
|
/// `sectors -= sectors % SECTOR_ALIGNMENT`.
|
|
#[test]
|
|
fn batch_trimmed_to_whole_units() {
|
|
with_watchdog(Duration::from_secs(10), || {
|
|
let calls = Arc::new(Mutex::new(Vec::new()));
|
|
// 9 sectors total = three 3-sector units.
|
|
let extents = vec![Extent {
|
|
start_lba: 0,
|
|
sector_count: 9,
|
|
}];
|
|
let src = RecordingSource {
|
|
capacity: 9,
|
|
calls: calls.clone(),
|
|
};
|
|
// batch=5: each read must be trimmed to 3 (one unit), so
|
|
// 9 sectors take three reads of 3, never a 5/4-sector read.
|
|
let mut pf = PrefetchedSectorSource::new(src, extents, 5, None).expect("spawn");
|
|
let (got, last) = drain_direct(&mut pf, 5, 16);
|
|
assert_eq!(last.unwrap(), 0);
|
|
assert_eq!(got.len(), 9 * 2048);
|
|
drop(pf);
|
|
let recorded = calls.lock().unwrap().clone();
|
|
assert!(
|
|
recorded.iter().all(|&(_, c)| c % SECTOR_ALIGNMENT == 0),
|
|
"every issued read must be a whole number of units, got {recorded:?}"
|
|
);
|
|
assert!(
|
|
recorded.iter().all(|&(_, c)| c == 3),
|
|
"batch=5 must trim to one 3-sector unit per read, got {recorded:?}"
|
|
);
|
|
});
|
|
}
|
|
|
|
/// An extent whose sector_count IS a multiple of 3 must deliver
|
|
/// exactly that many sectors and then cleanly EOF (no error on the
|
|
/// final aligned batch). Grounding: the trailing-tail guard only
|
|
/// fires for sub-unit leftovers; a unit-aligned extent forms full
|
|
/// units on its own (the comment at line ~188).
|
|
#[test]
|
|
fn unit_aligned_extent_delivers_all_and_eofs() {
|
|
with_watchdog(Duration::from_secs(10), || {
|
|
// 12 sectors = exactly four 3-sector units.
|
|
let extents = vec![Extent {
|
|
start_lba: 7,
|
|
sector_count: 12,
|
|
}];
|
|
let src = PatternSource { capacity: 100 };
|
|
let mut pf = PrefetchedSectorSource::new(src, extents, 6, None).expect("spawn");
|
|
let (got, last) = drain_direct(&mut pf, 6, 16);
|
|
assert_eq!(
|
|
last.unwrap(),
|
|
0,
|
|
"unit-aligned extent must EOF cleanly, not error"
|
|
);
|
|
assert_eq!(got.len(), 12 * 2048);
|
|
});
|
|
}
|
|
|
|
/// The underlying reader's error must propagate to the consumer as
|
|
/// an error (not Ok(0)/EOF), and its ErrorKind must survive the
|
|
/// round-trip through the channel. Grounding: the producer's
|
|
/// `Err(e) => tx.send(Err(e.into()))` arm, and `read_sectors`'
|
|
/// `Ok(Err(e)) => Err(IoError{source:e})`.
|
|
#[test]
|
|
fn reader_error_propagates_with_kind() {
|
|
with_watchdog(Duration::from_secs(10), || {
|
|
let extents = vec![Extent {
|
|
start_lba: 0,
|
|
sector_count: 3,
|
|
}];
|
|
let mut pf = PrefetchedSectorSource::new(ErrorSource, extents, 3, None).expect("spawn");
|
|
let mut buf = vec![0u8; 3 * 2048];
|
|
let r = pf.read_sectors(0, 3, &mut buf, false);
|
|
let err = r.expect_err("reader error must surface as Err, not EOF");
|
|
let io: std::io::Error = err.into();
|
|
assert_eq!(
|
|
io.kind(),
|
|
std::io::ErrorKind::PermissionDenied,
|
|
"underlying ErrorKind must survive the channel round-trip"
|
|
);
|
|
});
|
|
}
|
|
|
|
/// A read returning a byte count that is not a whole number of
|
|
/// sectors (n % 2048 != 0) must be rejected — never truncated and
|
|
/// advanced, which would split a sector and hand decrypt a partial
|
|
/// unit. Grounding: the `if n % 2048 != 0 { send Err }` guard.
|
|
#[test]
|
|
fn non_sector_multiple_read_rejected() {
|
|
with_watchdog(Duration::from_secs(10), || {
|
|
let extents = vec![Extent {
|
|
start_lba: 0,
|
|
sector_count: 9,
|
|
}];
|
|
let mut pf =
|
|
PrefetchedSectorSource::new(PartialSectorSource, extents, 3, None).expect("spawn");
|
|
let mut buf = vec![0u8; 3 * 2048];
|
|
let r = pf.read_sectors(0, 3, &mut buf, false);
|
|
let err = r.expect_err("split-sector read must be rejected");
|
|
let io: std::io::Error = err.into();
|
|
assert_eq!(
|
|
io.kind(),
|
|
std::io::ErrorKind::InvalidInput,
|
|
"split-sector read maps to ExtentNotUnitAligned (InvalidInput)"
|
|
);
|
|
});
|
|
}
|
|
|
|
/// A too-small consumer buffer in the direct `read_sectors` path
|
|
/// must error (InvalidInput), never silently drop the bytes past
|
|
/// `buf.len()`. Grounding: the `if filled.len() > buf.len()` guard
|
|
/// in `read_sectors` ("would silently drop filled[buf.len()..],
|
|
/// desyncing the stream").
|
|
#[test]
|
|
fn direct_read_too_small_buffer_errors() {
|
|
with_watchdog(Duration::from_secs(10), || {
|
|
let extents = vec![Extent {
|
|
start_lba: 0,
|
|
sector_count: 6,
|
|
}];
|
|
let src = PatternSource { capacity: 6 };
|
|
// batch=3 → producer fills 3 sectors (6144 bytes) per batch.
|
|
let mut pf = PrefetchedSectorSource::new(src, extents, 3, None).expect("spawn");
|
|
// Caller buffer holds only 1 sector — far too small.
|
|
let mut tiny = vec![0u8; 2048];
|
|
let r = pf.read_sectors(0, 1, &mut tiny, false);
|
|
let err = r.expect_err("too-small buffer must error, not truncate");
|
|
let io: std::io::Error = err.into();
|
|
assert_eq!(io.kind(), std::io::ErrorKind::InvalidInput);
|
|
drop(pf);
|
|
});
|
|
}
|
|
|
|
/// The producer delivers exactly the bytes the inner source
|
|
/// produced, in order, byte-for-byte. PatternSource tags each
|
|
/// sector with `(lba & 0xff)`, so the assembled stream must match a
|
|
/// reconstruction from the extent's LBA range. Guards against
|
|
/// off-by-one/duplicate/reorder in the offset bookkeeping.
|
|
#[test]
|
|
fn delivered_bytes_match_source_exactly() {
|
|
with_watchdog(Duration::from_secs(10), || {
|
|
let start = 40u32;
|
|
let count = 9u32; // three units
|
|
let extents = vec![Extent {
|
|
start_lba: start,
|
|
sector_count: count,
|
|
}];
|
|
let src = PatternSource { capacity: 1000 };
|
|
let mut pf = PrefetchedSectorSource::new(src, extents, 3, None).expect("spawn");
|
|
let (got, last) = drain_direct(&mut pf, 3, 16);
|
|
assert_eq!(last.unwrap(), 0);
|
|
assert_eq!(got.len(), (count as usize) * 2048);
|
|
// Reconstruct expected: sector i carries byte ((start+i)&0xff).
|
|
for i in 0..count {
|
|
let tag = ((start + i) & 0xff) as u8;
|
|
let off = i as usize * 2048;
|
|
assert!(
|
|
got[off..off + 2048].iter().all(|b| *b == tag),
|
|
"sector {i} (lba {}) content mismatch",
|
|
start + i
|
|
);
|
|
}
|
|
});
|
|
}
|
|
|
|
/// An empty extent list must EOF immediately (capacity 0, first
|
|
/// direct read returns Ok(0)) and must not deadlock. Grounding: the
|
|
/// producer's `while ext_idx < extents.len()` loop body never runs,
|
|
/// so `tx` drops and the consumer sees RecvError → Ok(0).
|
|
#[test]
|
|
fn empty_extents_eof_immediately() {
|
|
with_watchdog(Duration::from_secs(10), || {
|
|
let pf =
|
|
PrefetchedSectorSource::new(EndlessZeroSource, Vec::new(), 3, None).expect("spawn");
|
|
assert_eq!(pf.capacity_sectors(), 0);
|
|
let mut pf = pf;
|
|
let mut buf = vec![0u8; 3 * 2048];
|
|
let n = pf.read_sectors(0, 3, &mut buf, false).unwrap();
|
|
assert_eq!(n, 0, "empty extent list must EOF immediately");
|
|
});
|
|
}
|
|
|
|
/// A zero-length extent in the middle of the list must be skipped
|
|
/// (remaining == 0 → advance to next extent) without emitting a
|
|
/// batch and without stalling. Grounding: the `if remaining == 0 {
|
|
/// ext_idx += 1; continue }` branch.
|
|
#[test]
|
|
fn zero_length_extent_is_skipped() {
|
|
with_watchdog(Duration::from_secs(10), || {
|
|
let calls = Arc::new(Mutex::new(Vec::new()));
|
|
let extents = vec![
|
|
Extent {
|
|
start_lba: 10,
|
|
sector_count: 3,
|
|
},
|
|
Extent {
|
|
start_lba: 20,
|
|
sector_count: 0, // empty — must be skipped
|
|
},
|
|
Extent {
|
|
start_lba: 30,
|
|
sector_count: 3,
|
|
},
|
|
];
|
|
let src = RecordingSource {
|
|
capacity: 9999,
|
|
calls: calls.clone(),
|
|
};
|
|
let mut pf = PrefetchedSectorSource::new(src, extents, 3, None).expect("spawn");
|
|
let (got, last) = drain_direct(&mut pf, 3, 16);
|
|
assert_eq!(last.unwrap(), 0);
|
|
assert_eq!(got.len(), 6 * 2048, "two non-empty extents = 6 sectors");
|
|
drop(pf);
|
|
let recorded = calls.lock().unwrap().clone();
|
|
// No read should target LBA 20 (the empty extent).
|
|
assert_eq!(
|
|
recorded,
|
|
vec![(10, 3), (30, 3)],
|
|
"empty extent must produce no read"
|
|
);
|
|
});
|
|
}
|
|
|
|
/// A 4-sector extent (one full unit + a 1-sector tail) must
|
|
/// deliver the 3-sector unit and then error on the 1-sector
|
|
/// remainder — exercising the trim-within-batch path
|
|
/// (`sectors -= sectors % 3` lands on 3, leaving remaining=1) that
|
|
/// then hits the sub-unit guard on the next iteration. Distinct
|
|
/// control flow from the 8-sector case. Grounding: trailing-tail
|
|
/// guard plus the unit-trim block.
|
|
#[test]
|
|
fn four_sector_extent_errors_on_one_sector_tail() {
|
|
with_watchdog(Duration::from_secs(10), || {
|
|
let extents = vec![Extent {
|
|
start_lba: 0,
|
|
sector_count: 4,
|
|
}];
|
|
let src = PatternSource { capacity: 100 };
|
|
// batch=9 (>4) so the first iter requests 4, trims to 3.
|
|
let mut pf = PrefetchedSectorSource::new(src, extents, 9, None).expect("spawn");
|
|
let mut buf = vec![0u8; 9 * 2048];
|
|
let n0 = pf.read_sectors(0, 9, &mut buf, false).unwrap();
|
|
assert_eq!(n0, 3 * 2048, "first batch must be exactly one unit");
|
|
let r = pf.read_sectors(0, 9, &mut buf, false);
|
|
let err = r.expect_err("1-sector tail must error");
|
|
let io: std::io::Error = err.into();
|
|
assert_eq!(io.kind(), std::io::ErrorKind::InvalidInput);
|
|
});
|
|
}
|
|
|
|
/// Many sequential direct reads across MANY extents must all flow
|
|
/// through the fixed recycle pool without deadlock — a stronger
|
|
/// version of the pool-depth regression that also crosses extent
|
|
/// boundaries (offset reset to 0, ext_idx advance). Grounding: the
|
|
/// recycle-pool comment in `read_sectors`.
|
|
#[test]
|
|
fn many_extents_drain_without_deadlock() {
|
|
with_watchdog(Duration::from_secs(15), || {
|
|
// 10 extents of 3 sectors each = 30 sectors total, well past
|
|
// the 3-buffer pool, and 10 extent transitions.
|
|
let extents: Vec<Extent> = (0..10)
|
|
.map(|i| Extent {
|
|
start_lba: i * 1000,
|
|
sector_count: 3,
|
|
})
|
|
.collect();
|
|
let src = PatternSource { capacity: 999999 };
|
|
let mut pf = PrefetchedSectorSource::new(src, extents, 3, None).expect("spawn");
|
|
let (got, last) = drain_direct(&mut pf, 3, 64);
|
|
assert_eq!(last.unwrap(), 0);
|
|
assert_eq!(got.len(), 30 * 2048, "all 10 extents must be drained");
|
|
});
|
|
}
|
|
}
|