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`SliceRingBuffer` is unsound and has multiple security advisories [1] [2]. There has been no apparent progress on fixes since May 2025 [3]. The crate's large volume of interdependent `unsafe` blocks will likely make it very tricky to maintain. While a memory-mapped deque is a very cool idea, it is time to move on for now. Let's replace `SliceRingBuffer` with a more traditional double-ended queue. These queues don't covert to slice, but we don't really *need* a slice. At present, slice is mostly used to align the end of `Window` (with the most recent samples) to the filter taps. We can do that just as easily with a `DoubleEndedIterator`. * Make `Window` convertible to an iterator of numbers, via `IntoIterator`. Replace all uses of slices with iterators. * Remove slice conversions and accessors from Window. They're still technically accessible via `inner()`, but nothing uses them. [1]: https://rustsec.org/advisories/RUSTSEC-2025-0044 [2]: https://rustsec.org/advisories/RUSTSEC-2020-0158 [3]: LiquidityC/slice_ring_buffer#12
Previously, `FilterCoeff` were stored in reverse order, with feedforward lag 0 stored *last*. This was convenient when `Window` coerced to slice. Now that we iterate over `Window` in reverse order, reversing the filter taps does not serve us. It is also confusing: the taps are in "normal" order in `FilterCoeff::from_slice()`, but later reads via `as_slice()` show them reversed. Ick. Put filter taps in their proper order.
Replace `SliceRingBuffer` with a standard `VecDeque` in our FIR filter `Window` implementation. The crate dependency is dropped.
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SliceRingBufferis unsound and has multiple security advisories 1 2. There has been no apparent progress on fixes since May 2025 3. The crate's large volume of interdependentunsafeblocks will likely make it very tricky to maintain.SliceRingBufferbacks the FIR filterWindow. The slice coercion is used to align the back of theWindow(with the most recent samples) with the FIR filter taps. We don't actually need a slice for this: we can get by with aDoubleEndedIteratorinstead.Make
Windowconvertible to an iterator of numbers, viaIntoIterator. Replace all uses of slices with iterators.Store FIR
FilterCoefftaps in "proper" order, instead of reversed. Since we use iterators instead of slices, reverse-order is no longer convenient.Replace
SliceRingBufferwithstd::collections::VecDeque.Testing indicates that
VecDequemay be up to twice as fast as the previous implementation.Closes #53