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//! A dynamically sized, multi-channel audio buffer. use crate::buf::{Buf, BufMut}; use crate::channel::{Channel, ChannelMut}; use crate::sample::Sample; use std::cmp; use std::fmt; use std::hash; use std::mem; use std::ops; use std::ptr; use std::slice; mod iter; pub use self::iter::{Iter, IterMut}; /// A dynamically sized, multi-channel audio buffer. /// /// An audio buffer is constrained to only support sample-apt types. For more /// information of what this means, see [Sample]. /// /// This kind of buffer stores each channel in its own heap-allocated slice of /// memory, meaning they can be manipulated more cheaply independently of each /// other than say [Interleaved][crate::Interleaved] or /// [Sequential][crate::Sequential]. These would have to re-organize every /// constituent channel when resizing, while [Dynamic] generally only requires /// [growing and shrinking][std::alloc::Allocator] of a memory region. /// /// This kind of buffer is a good choice if you need to /// [resize][Dynamic::resize] frequently. pub struct Dynamic<T> where T: Sample, { /// The stored data for each channel. data: RawSlice<RawSlice<T>>, /// The number of channels stored. channels: usize, /// The capacity of channels stored. channels_cap: usize, /// The length of each channel. frames: usize, /// Allocated capacity of each channel. Each channel is guaranteed to be /// filled with as many values as is specified in this capacity. frames_cap: usize, } impl<T> Dynamic<T> where T: Sample, { /// Construct a new empty audio buffer. /// /// # Examples /// /// ```rust /// let mut buffer = rotary::Dynamic::<f32>::new(); /// /// assert_eq!(buffer.frames(), 0); /// ``` pub fn new() -> Self { Self { // Safety: we know that a newly created vector is non-null. data: RawSlice::empty(), channels: 0, channels_cap: 0, frames: 0, frames_cap: 0, } } /// Allocate an audio buffer with the given topology. A "topology" is a /// given number of `channels` and the corresponding number of `frames` in /// their buffers. /// /// # Examples /// /// ```rust /// let mut buffer = rotary::Dynamic::<f32>::with_topology(4, 256); /// /// assert_eq!(buffer.frames(), 256); /// assert_eq!(buffer.channels(), 4); /// ``` pub fn with_topology(channels: usize, frames: usize) -> Self { let mut data = RawSlice::uninit(channels); for n in 0..channels { // Safety: We just allocated the vector w/ a capacity matching channels. unsafe { data.write(n, RawSlice::zeroed(frames)); } } Self { // Safety: we just initialized the associated array with the // expected topology. data, channels, channels_cap: channels, frames, frames_cap: frames, } } /// Allocate an audio buffer from a fixed-size array. /// /// See [dynamic!]. /// /// # Examples /// /// ```rust /// use rotary::BitSet; /// /// let mut buffer = rotary::Dynamic::<f32>::from_array([[2.0; 256]; 4]); /// /// assert_eq!(buffer.frames(), 256); /// assert_eq!(buffer.channels(), 4); /// /// for chan in &buffer { /// assert_eq!(chan, vec![2.0; 256]); /// } /// ``` pub fn from_array<const F: usize, const C: usize>(channels: [[T; F]; C]) -> Self { return Self { // Safety: We just created the box with the data so we know that // it's initialized. data: unsafe { data_from_array(channels) }, channels: C, channels_cap: C, frames: F, frames_cap: F, }; #[inline] unsafe fn data_from_array<T: Sample, const F: usize, const C: usize>( values: [[T; F]; C], ) -> RawSlice<RawSlice<T>> { let mut data = Vec::with_capacity(C); for frames in std::array::IntoIter::new(values) { let slice = Box::<[T]>::from(frames); let slice = ptr::NonNull::new_unchecked(Box::into_raw(slice) as *mut T); data.push(RawSlice { data: slice }); } RawSlice { data: ptr::NonNull::new_unchecked(mem::ManuallyDrop::new(data).as_mut_ptr()), } } } /// Get the number of frames in the channels of an audio buffer. /// /// # Examples /// /// ```rust /// let mut buffer = rotary::Dynamic::<f32>::new(); /// /// assert_eq!(buffer.frames(), 0); /// buffer.resize(256); /// assert_eq!(buffer.frames(), 256); /// ``` pub fn frames(&self) -> usize { self.frames } /// Check how many channels there are in the buffer. /// /// # Examples /// /// ```rust /// let mut buffer = rotary::Dynamic::<f32>::new(); /// /// assert_eq!(buffer.channels(), 0); /// buffer.resize_channels(2); /// assert_eq!(buffer.channels(), 2); /// ``` pub fn channels(&self) -> usize { self.channels } /// Construct a mutable iterator over all available channels. /// /// # Examples /// /// ``` /// use rand::Rng as _; /// /// let mut buffer = rotary::Dynamic::<f32>::with_topology(4, 256); /// /// let all_zeros = vec![0.0; 256]; /// /// for chan in buffer.iter() { /// assert_eq!(chan, &all_zeros[..]); /// } /// ``` pub fn iter(&self) -> Iter<'_, T> { // Safety: we're using a trusted length to build the slice. unsafe { Iter::new(self.data.as_ref(self.channels), self.frames) } } /// Construct a mutable iterator over all available channels. /// /// # Examples /// /// ``` /// use rand::Rng as _; /// /// let mut buffer = rotary::Dynamic::<f32>::with_topology(4, 256); /// let mut rng = rand::thread_rng(); /// /// for chan in buffer.iter_mut() { /// rng.fill(chan); /// } /// ``` pub fn iter_mut(&mut self) -> IterMut<'_, T> { // Safety: we're using a trusted length to build the slice. unsafe { IterMut::new(self.data.as_mut(self.channels), self.frames) } } /// Set the size of the buffer. The size is the size of each channel's /// buffer. /// /// If the size of the buffer increases as a result, the new regions in the /// frames will be zeroed. If the size decreases, the region will be left /// untouched. So if followed by another increase, the data will be "dirty". /// /// # Examples /// /// ```rust /// let mut buffer = rotary::Dynamic::<f32>::new(); /// /// assert_eq!(buffer.channels(), 0); /// assert_eq!(buffer.frames(), 0); /// /// buffer.resize_channels(4); /// buffer.resize(256); /// /// assert_eq!(buffer[1][128], 0.0); /// buffer[1][128] = 42.0; /// /// assert_eq!(buffer.channels(), 4); /// assert_eq!(buffer.frames(), 256); /// ``` /// /// Decreasing and increasing the size will not touch a buffer that has /// already been allocated. /// /// ```rust /// # let mut buffer = rotary::Dynamic::<f32>::with_topology(4, 256); /// assert_eq!(buffer[1][128], 0.0); /// buffer[1][128] = 42.0; /// /// buffer.resize(64); /// assert!(buffer[1].get(128).is_none()); /// /// buffer.resize(256); /// assert_eq!(buffer[1][128], 42.0); /// ``` pub fn resize(&mut self, frames: usize) { if self.frames_cap < frames { let from = self.frames_cap; let to = <RawSlice<T>>::next_cap(from, frames); if self.channels_cap > 0 { let additional = to - from; for n in 0..self.channels_cap { // Safety: We control the known sizes, so we can guarantee // that the slice is allocated and sized tio exactly `from`. unsafe { self.data .get_unchecked_mut(n) .reserve_zeroed(from, additional) }; } } self.frames_cap = to; } self.frames = frames; } /// Set the number of channels in use. /// /// If the size of the buffer increases as a result, the new channels will /// be zeroed. If the size decreases, the channels that falls outside of the /// new size will be dropped. /// /// # Examples /// /// ```rust /// let mut buffer = rotary::Dynamic::<f32>::new(); /// /// assert_eq!(buffer.channels(), 0); /// assert_eq!(buffer.frames(), 0); /// /// buffer.resize_channels(4); /// buffer.resize(256); /// /// assert_eq!(buffer.channels(), 4); /// assert_eq!(buffer.frames(), 256); /// ``` pub fn resize_channels(&mut self, channels: usize) { if channels == self.channels { return; } if channels > self.channels_cap { let old_cap = self.channels_cap; let new_cap = <RawSlice<RawSlice<T>>>::next_cap(old_cap, channels); let additional = new_cap - old_cap; // Safety: We trust that the old capacity is correct. unsafe { self.data.reserve_uninit(old_cap, additional); } for n in old_cap..new_cap { let slice = RawSlice::zeroed(self.frames_cap); // Safety: we control the capacity of channels and have just // guranteed above that it is appropriate. unsafe { self.data.write(n, slice); } } self.channels_cap = new_cap; } debug_assert!(channels <= self.channels_cap); self.channels = channels; } /// Get a reference to the buffer of the given channel. /// /// # Examples /// /// ```rust /// let mut buffer = rotary::Dynamic::<f32>::new(); /// /// buffer.resize_channels(4); /// buffer.resize(256); /// /// let expected = vec![0.0; 256]; /// /// assert_eq!(Some(&expected[..]), buffer.get(0)); /// assert_eq!(Some(&expected[..]), buffer.get(1)); /// assert_eq!(Some(&expected[..]), buffer.get(2)); /// assert_eq!(Some(&expected[..]), buffer.get(3)); /// assert_eq!(None, buffer.get(4)); /// ``` pub fn get(&self, channel: usize) -> Option<&[T]> { if channel < self.channels { // Safety: We control the length of each channel so we can assert that // it is both allocated and initialized up to `len`. unsafe { Some(self.data.get_unchecked(channel).as_ref(self.frames)) } } else { None } } /// Get the given channel or initialize the buffer with the default value. /// /// # Examples /// /// ```rust /// let mut buffer = rotary::Dynamic::<f32>::new(); /// /// buffer.resize(256); /// /// let expected = vec![0f32; 256]; /// /// assert_eq!(buffer.get_or_default(0), &expected[..]); /// assert_eq!(buffer.get_or_default(1), &expected[..]); /// /// assert_eq!(buffer.channels(), 2); /// ``` pub fn get_or_default(&mut self, channel: usize) -> &[T] { self.resize_channels(channel + 1); // Safety: We initialized the given index just above and we know the // trusted length. unsafe { self.data.get_unchecked(channel).as_ref(self.frames) } } /// Get a mutable reference to the buffer of the given channel. /// /// # Examples /// /// ```rust /// use rand::Rng as _; /// /// let mut buffer = rotary::Dynamic::<f32>::new(); /// /// buffer.resize_channels(2); /// buffer.resize(256); /// /// let mut rng = rand::thread_rng(); /// /// if let Some(left) = buffer.get_mut(0) { /// rng.fill(left); /// } /// /// if let Some(right) = buffer.get_mut(1) { /// rng.fill(right); /// } /// ``` pub fn get_mut(&mut self, channel: usize) -> Option<&mut [T]> { if channel < self.channels { // Safety: We control the length of each channel so we can assert that // it is both allocated and initialized up to `len`. unsafe { Some(self.data.get_unchecked_mut(channel).as_mut(self.frames)) } } else { None } } /// Get the given channel or initialize the buffer with the default value. /// /// If a channel that is out of bound is queried, the buffer will be empty. /// /// # Examples /// /// ```rust /// use rand::Rng as _; /// /// let mut buffer = rotary::Dynamic::<f32>::new(); /// /// buffer.resize(256); /// /// let mut rng = rand::thread_rng(); /// /// rng.fill(buffer.get_or_default_mut(0)); /// rng.fill(buffer.get_or_default_mut(1)); /// /// assert_eq!(buffer.channels(), 2); /// ``` pub fn get_or_default_mut(&mut self, channel: usize) -> &mut [T] { self.resize_channels(channel + 1); // Safety: We initialized the given index just above and we know the // trusted length. unsafe { self.data.get_unchecked_mut(channel).as_mut(self.frames) } } /// Convert into a vector of vectors. /// /// This is provided for the [Dynamic] type because it's a very cheap /// oepration due to its memory topology. No copying of the underlying /// buffers is necessary. /// /// # Examples /// /// ```rust /// let mut buffer = rotary::Dynamic::<f32>::new(); /// buffer.resize_channels(4); /// buffer.resize(512); /// /// let expected = vec![0.0; 512]; /// /// let buffers = buffer.into_vectors(); /// assert_eq!(buffers.len(), 4); /// assert_eq!(buffers[0], &expected[..]); /// assert_eq!(buffers[1], &expected[..]); /// assert_eq!(buffers[2], &expected[..]); /// assert_eq!(buffers[3], &expected[..]); /// ``` pub fn into_vectors(self) -> Vec<Vec<T>> { self.into_vectors_if(|_| true) } /// Convert into a vector of vectors using a condition. /// /// This is provided for the [Dynamic] type because it's a very cheap /// oepration due to its memory topology. No copying of the underlying /// buffers is necessary. /// /// Channels which does not match the condition will be filled with an empty /// vector. /// /// # Examples /// /// ```rust /// let mut buffer = rotary::Dynamic::<f32>::new(); /// buffer.resize_channels(4); /// buffer.resize(512); /// /// let expected = vec![0.0; 512]; /// /// let buffers = buffer.into_vectors_if(|n| n != 1); /// assert_eq!(buffers.len(), 4); /// assert_eq!(buffers[0], &expected[..]); /// assert_eq!(buffers[1], &[][..]); /// assert_eq!(buffers[2], &expected[..]); /// assert_eq!(buffers[3], &expected[..]); /// ``` pub fn into_vectors_if(self, mut condition: impl FnMut(usize) -> bool) -> Vec<Vec<T>> { let mut this = mem::ManuallyDrop::new(self); let mut vecs = Vec::with_capacity(this.channels); let frames_cap = this.frames_cap; for n in 0..this.channels { // Safety: The capacity end lengths are trusted since they're part // of the audio buffer. unsafe { let mut slice = this.data.read(n); if condition(n) { vecs.push(slice.into_vec(this.frames, frames_cap)); } else { slice.drop_in_place(frames_cap); vecs.push(Vec::new()); } } } // Drop the tail of the channels capacity which is not in use. for n in this.channels..this.channels_cap { // Safety: The capacity end lengths are trusted since they're part // of the audio buffer. unsafe { this.data.get_unchecked_mut(n).drop_in_place(frames_cap); } } // Drop the backing vector for all channels. // // Safety: we trust the capacity provided here. unsafe { let cap = this.channels_cap; this.data.drop_in_place(cap); } vecs } } // Safety: dynamic is simply a container of T's, any Send/Sync properties are // inherited. unsafe impl<T> Send for Dynamic<T> where T: Sample + Send {} unsafe impl<T> Sync for Dynamic<T> where T: Sample + Sync {} /// Allocate an audio buffer from a fixed-size array. /// /// See [dynamic!]. impl<T, const F: usize, const C: usize> From<[[T; F]; C]> for Dynamic<T> where T: Sample, { #[inline] fn from(channels: [[T; F]; C]) -> Self { Self::from_array(channels) } } impl<T> fmt::Debug for Dynamic<T> where T: Sample + fmt::Debug, { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { f.debug_list().entries(self.iter()).finish() } } impl<T> cmp::PartialEq for Dynamic<T> where T: Sample + cmp::PartialEq, { fn eq(&self, other: &Self) -> bool { self.iter().eq(other.iter()) } } impl<T> cmp::Eq for Dynamic<T> where T: Sample + cmp::Eq {} impl<T> cmp::PartialOrd for Dynamic<T> where T: Sample + cmp::PartialOrd, { fn partial_cmp(&self, other: &Self) -> Option<cmp::Ordering> { self.iter().partial_cmp(other.iter()) } } impl<T> cmp::Ord for Dynamic<T> where T: Sample + cmp::Ord, { fn cmp(&self, other: &Self) -> cmp::Ordering { self.iter().cmp(other.iter()) } } impl<T> hash::Hash for Dynamic<T> where T: Sample + hash::Hash, { fn hash<H: hash::Hasher>(&self, state: &mut H) { for channel in self.iter() { channel.hash(state); } } } impl<'a, T> IntoIterator for &'a Dynamic<T> where T: Sample, { type IntoIter = Iter<'a, T>; type Item = <Self::IntoIter as Iterator>::Item; fn into_iter(self) -> Self::IntoIter { self.iter() } } impl<'a, T> IntoIterator for &'a mut Dynamic<T> where T: Sample, { type IntoIter = IterMut<'a, T>; type Item = <Self::IntoIter as Iterator>::Item; fn into_iter(self) -> Self::IntoIter { self.iter_mut() } } impl<T> ops::Index<usize> for Dynamic<T> where T: Sample, { type Output = [T]; fn index(&self, index: usize) -> &Self::Output { match self.get(index) { Some(slice) => slice, None => panic!("index `{}` is not a channel", index), } } } impl<T> ops::IndexMut<usize> for Dynamic<T> where T: Sample, { fn index_mut(&mut self, index: usize) -> &mut Self::Output { match self.get_mut(index) { Some(slice) => slice, None => panic!("index `{}` is not a channel", index,), } } } impl<T> Drop for Dynamic<T> where T: Sample, { fn drop(&mut self) { for n in 0..self.channels_cap { // Safety: We're being dropped, so there's no subsequent access to // the current collection. unsafe { self.data .get_unchecked_mut(n) .drop_in_place(self.frames_cap); } } // Safety: We trust the length of the underlying array. unsafe { self.data.drop_in_place(self.channels_cap); } } } impl<T> Buf<T> for Dynamic<T> where T: Sample, { fn frames(&self) -> usize { self.frames } fn channels(&self) -> usize { self.channels } fn channel(&self, channel: usize) -> Channel<'_, T> { Channel::linear(&self[channel]) } } impl<T> BufMut<T> for Dynamic<T> where T: Sample, { fn channel_mut(&mut self, channel: usize) -> ChannelMut<'_, T> { ChannelMut::linear(&mut self[channel]) } fn resize(&mut self, frames: usize) { Self::resize(self, frames); } fn resize_topology(&mut self, channels: usize, frames: usize) { Self::resize(self, frames); self.resize_channels(channels); } } /// A raw slice. #[repr(transparent)] #[derive(Clone, Copy)] struct RawSlice<T> { data: ptr::NonNull<T>, } impl<T> RawSlice<T> { const MIN_NON_ZERO_CAP: usize = if mem::size_of::<T>() == 1 { 8 } else if mem::size_of::<T>() <= 256 { 4 } else { 1 }; /// Calculate the next capacity. fn next_cap(from: usize, to: usize) -> usize { let to = usize::max(from * 2, to); let to = usize::max(Self::MIN_NON_ZERO_CAP, to); to } /// Construct an empty raw slice. fn empty() -> Self { Self { data: unsafe { ptr::NonNull::new_unchecked(Vec::new().as_mut_ptr()) }, } } /// Construct a new raw slice with the given capacity leaving the memory /// uninitialized. fn uninit(cap: usize) -> Self { // Safety: We're just allocating the vector so we knows it's correctly // sized and aligned. unsafe { let data = Vec::with_capacity(cap); let data = ptr::NonNull::new_unchecked(mem::ManuallyDrop::new(data).as_mut_ptr()); Self { data } } } /// Construct a new raw slice with the given capacity. fn zeroed(cap: usize) -> Self where T: Sample, { // Safety: the type constrain of `T` guarantees that an all-zeros bit // pattern is legal. unsafe { let mut data = Vec::with_capacity(cap); ptr::write_bytes(data.as_mut_ptr(), 0, cap); let data = ptr::NonNull::new_unchecked(mem::ManuallyDrop::new(data).as_mut_ptr()); Self { data } } } /// Resize the slice in place by reserving `additional` more elements in it. /// /// # Safety /// /// The provided `len` must watch the length for which it was allocated. /// This will change the underlying allocation, so subsequent calls must /// provide the new length of `len + additional`. unsafe fn reserve_zeroed(&mut self, len: usize, additional: usize) where T: Sample, { // Note: we need to provide `len` for the `reserve_exact` calculation to // below to be correct. let mut channel = Vec::from_raw_parts(self.data.as_ptr(), len, len); channel.reserve_exact(additional); // Safety: the type constrain of `T` guarantees that an all-zeros bit pattern is legal. ptr::write_bytes(channel.as_mut_ptr().add(len), 0, additional); self.data = ptr::NonNull::new_unchecked(mem::ManuallyDrop::new(channel).as_mut_ptr()); } /// Resize the slice in place by reserving `additional` more elements in it /// without initializing them. /// /// # Safety /// /// The provided `len` must watch the length for which it was allocated. /// This will change the underlying allocation, so subsequent calls must /// provide the new length of `len + additional`. unsafe fn reserve_uninit(&mut self, len: usize, additional: usize) { // Note: we need to provide `len` for the `reserve_exact` calculation to // below to be correct. let mut channel = Vec::from_raw_parts(self.data.as_ptr(), len, len); channel.reserve_exact(additional); self.data = ptr::NonNull::new_unchecked(mem::ManuallyDrop::new(channel).as_mut_ptr()); } /// Get a reference to the value at the given offset. /// /// # Safety /// /// The caller is resonsible for asserting that the value at the given /// location has an initialized bit pattern and is not out of bounds. unsafe fn get_unchecked(&self, n: usize) -> &T { &*self.data.as_ptr().add(n) } /// Get a mutable reference to the value at the given offset. /// /// # Safety /// /// The caller is resonsible for asserting that the value at the given /// location has an initialized bit pattern and is not out of bounds. unsafe fn get_unchecked_mut(&mut self, n: usize) -> &mut T { &mut *self.data.as_ptr().add(n) } /// Read the value at the given offset. /// /// # Safety /// /// The caller is resonsible for asserting that the value at the given /// location has an initialized bit pattern and is not out of bounds. unsafe fn read(&self, n: usize) -> T { ptr::read(self.data.as_ptr().add(n)) } /// Write a value at the given offset. /// /// # Safety /// /// The caller is responsible for asserting that the written to offset is /// not out of bounds. unsafe fn write(&mut self, n: usize, value: T) { ptr::write(self.data.as_ptr().add(n), value) } /// Get the raw slice as a slice. /// /// # Safety /// /// The incoming len must represent a valid slice of initialized data. /// The produced lifetime must be bounded to something valid! unsafe fn as_ref<'a>(self, len: usize) -> &'a [T] { slice::from_raw_parts(self.data.as_ptr() as *const _, len) } /// Get the raw slice as a mutable slice. /// /// # Safety /// /// The incoming len must represent a valid slice of initialized data. /// The produced lifetime must be bounded to something valid! unsafe fn as_mut<'a>(self, len: usize) -> &'a mut [T] { slice::from_raw_parts_mut(self.data.as_ptr(), len) } /// Drop the slice in place. /// /// # Safety /// /// The provided `len` must match the allocated length of the raw slice. /// /// After calling drop, the slice must not be used every again because the /// data it is pointing to have been dropped. unsafe fn drop_in_place(&mut self, len: usize) { let _ = Vec::from_raw_parts(self.data.as_ptr(), 0, len); } /// Convert into a vector. /// /// # Safety /// /// The provided `len` and `cap` must match the ones used when allocating /// the slice. /// /// The underlying slices must be dropped and forgotten after this /// operation. pub(crate) unsafe fn into_vec(self, len: usize, cap: usize) -> Vec<T> { Vec::from_raw_parts(self.data.as_ptr(), len, cap) } }