Struct LocalRb

pub struct LocalRb<S: Storage + ?Sized> { /* private fields */ }

Ring buffer for single-threaded use only.

Slightly faster than multi-threaded version because it doesn’t synchronize cache.

Implementations

impl<S: Storage> LocalRb<S>

pub unsafe fn from_raw_parts(storage: S, read: usize, write: usize) -> Self

Constructs ring buffer from storage and indices.

Safety

The items in storage inside read..write range must be initialized, items outside this range must be uninitialized. read and write positions must be valid (see implementation details).

pub unsafe fn into_raw_parts(self) -> (S, usize, usize)

Destructures ring buffer into underlying storage and read and write indices.

Safety

Initialized contents of the storage must be properly dropped.

impl<T> LocalRb<Heap<T>>

pub fn new(capacity: usize) -> Self

Creates a new instance of a ring buffer.

Panics if allocation failed or capacity is zero.

pub fn try_new(capacity: usize) -> Result<Self, TryReserveError>

Creates a new instance of a ring buffer returning an error if allocation failed.

Panics if capacity is zero.

Trait Implementations

impl<S: Storage + ?Sized> AsMut<LocalRb<S>> for LocalRb<S>

fn as_mut(&mut self) -> &mut Self

Converts this type into a mutable reference of the (usually inferred) input type.

impl<S: Storage + ?Sized> AsRef<LocalRb<S>> for LocalRb<S>

fn as_ref(&self) -> &Self

Converts this type into a shared reference of the (usually inferred) input type.

impl<S: Storage + ?Sized> Consumer for LocalRb<S>

unsafe fn set_read_index(&self, value: usize)

Set read index.

unsafe fn advance_read_index(&self, count: usize)

Moves read pointer by count places forward.

fn occupied_slices( &self, ) -> (&[MaybeUninit<Self::Item>], &[MaybeUninit<Self::Item>])

Provides a direct access to the ring buffer occupied memory. The difference from Self::as_slices is that this method provides slices of MaybeUninit, so items may be moved out of slices.

unsafe fn occupied_slices_mut( &mut self, ) -> (&mut [MaybeUninit<Self::Item>], &mut [MaybeUninit<Self::Item>])

Provides a direct mutable access to the ring buffer occupied memory.

fn as_slices(&self) -> (&[Self::Item], &[Self::Item])

Returns a pair of slices which contain, in order, the contents of the ring buffer.

fn as_mut_slices(&mut self) -> (&mut [Self::Item], &mut [Self::Item])

Returns a pair of mutable slices which contain, in order, the contents of the ring buffer.

fn first(&self) -> Option<&Self::Item>

Returns a reference to the eldest item in the ring buffer, if exists.

fn first_mut(&mut self) -> Option<&mut Self::Item>

Returns a mutable reference to the eldest item in the ring buffer, if exists.

fn last(&self) -> Option<&Self::Item>

Returns a reference to the most recent item in the ring buffer, if exists.

fn last_mut(&mut self) -> Option<&mut Self::Item>

Returns a mutable reference to the most recent item in the ring buffer, if exists.

fn try_pop(&mut self) -> Option<Self::Item>

Removes the eldest item from the ring buffer and returns it.

fn try_peek(&self) -> Option<&Self::Item>

Returns the reference to the eldest item without removing it from the buffer.

fn peek_slice_uninit(&self, elems: &mut [MaybeUninit<Self::Item>]) -> usize

Copies items from the ring buffer to an uninit slice without removing them from the ring buffer.

fn peek_slice(&self, elems: &mut [Self::Item]) -> usize

where Self::Item: Copy,

Copies items from the ring buffer to a slice without removing them from the ring buffer.

fn pop_slice_uninit(&mut self, elems: &mut [MaybeUninit<Self::Item>]) -> usize

Removes items from the ring buffer and writes them into an uninit slice.

fn pop_slice(&mut self, elems: &mut [Self::Item]) -> usize

where Self::Item: Copy,

Removes items from the ring buffer and writes them into a slice.

fn pop_iter(&mut self) -> PopIter<'_, Self>

Returns an iterator that removes items one by one from the ring buffer.

fn iter(&self) -> Iter<'_, Self>

Returns a front-to-back iterator containing references to items in the ring buffer.

fn iter_mut(&mut self) -> IterMut<'_, Self>

Returns a front-to-back iterator that returns mutable references to items in the ring buffer.

fn skip(&mut self, count: usize) -> usize

Removes at most count and at least min(count, Self::len()) items from the buffer and safely drops them.

fn clear(&mut self) -> usize

Removes all items from the buffer and safely drops them.

fn write_into<S: Write>( &mut self, writer: &mut S, count: Option<usize>, ) -> Option<Result<usize>>

where Self: Consumer<Item = u8>,

Removes at most first count bytes from the ring buffer and writes them into a Write instance. If count is None then as much as possible bytes will be written.

impl<T, const N: usize> Default for LocalRb<Array<T, N>>

fn default() -> Self

Returns the “default value” for a type.

impl<S: Storage + ?Sized> Drop for LocalRb<S>

fn drop(&mut self)

Executes the destructor for this type.

impl<T, const N: usize> From<[T; N]> for LocalRb<Array<T, N>>

fn from(value: [T; N]) -> Self

Converts to this type from the input type.

impl<T> From<Box<[T]>> for LocalRb<Heap<T>>

fn from(value: Box<[T]>) -> Self

Converts to this type from the input type.

impl<T> From<Vec<T>> for LocalRb<Heap<T>>

fn from(value: Vec<T>) -> Self

Converts to this type from the input type.

impl<S: Storage> IntoIterator for LocalRb<S>

where Self: Sized,

type Item = <LocalRb<S> as Observer>::Item

The type of the elements being iterated over.

type IntoIter = IntoIter<LocalRb<S>>

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl<S: Storage + ?Sized> Observer for LocalRb<S>

type Item = <S as Storage>::Item

fn capacity(&self) -> NonZeroUsize

Capacity of the ring buffer.

fn read_index(&self) -> usize

Index of the last item in the ring buffer.

fn write_index(&self) -> usize

Index of the next empty slot in the ring buffer.

unsafe fn unsafe_slices( &self, start: usize, end: usize, ) -> (&[MaybeUninit<S::Item>], &[MaybeUninit<S::Item>])

Get slice between start and end indices.

unsafe fn unsafe_slices_mut( &self, start: usize, end: usize, ) -> (&mut [MaybeUninit<S::Item>], &mut [MaybeUninit<S::Item>])

Get mutable slice between start and end indices.

fn read_is_held(&self) -> bool

Whether read end is held by consumer.

fn write_is_held(&self) -> bool

Whether write end is held by producer.

fn occupied_len(&self) -> usize

The number of items stored in the buffer.

fn vacant_len(&self) -> usize

The number of remaining free places in the buffer.

fn is_empty(&self) -> bool

Checks if the ring buffer is empty.

fn is_full(&self) -> bool

Checks if the ring buffer is full.

impl<S: Storage + ?Sized> Producer for LocalRb<S>

unsafe fn set_write_index(&self, value: usize)

Set read index.

unsafe fn advance_write_index(&self, count: usize)

Moves write pointer by count places forward.

fn vacant_slices( &self, ) -> (&[MaybeUninit<Self::Item>], &[MaybeUninit<Self::Item>])

Provides a direct access to the ring buffer vacant memory.

fn vacant_slices_mut( &mut self, ) -> (&mut [MaybeUninit<Self::Item>], &mut [MaybeUninit<Self::Item>])

Mutable version of Self::vacant_slices.

fn try_push(&mut self, elem: Self::Item) -> Result<(), Self::Item>

Appends an item to the ring buffer.

fn push_iter<I: Iterator<Item = Self::Item>>(&mut self, iter: I) -> usize

Appends items from an iterator to the ring buffer. Elements that haven’t been added to the ring buffer remain in the iterator.

fn push_slice(&mut self, elems: &[Self::Item]) -> usize

where Self::Item: Copy,

Appends items from slice to the ring buffer.

fn read_from<S: Read>( &mut self, reader: &mut S, count: Option<usize>, ) -> Option<Result<usize>>

where Self: Producer<Item = u8>,

Reads at most count bytes from Read instance and appends them to the ring buffer. If count is None then as much as possible bytes will be read.

impl<S: Storage> Read for LocalRb<S>

where Self: Consumer<Item = u8>,

fn read(&mut self, buf: &mut [u8]) -> Result<usize>

Pull some bytes from this source into the specified buffer, returning how many bytes were read.

fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> Result<usize, Error>

Like read, except that it reads into a slice of buffers.

fn is_read_vectored(&self) -> bool

🔬This is a nightly-only experimental API. (can_vector)

Determines if this Reader has an efficient read_vectored implementation.

fn read_to_end(&mut self, buf: &mut Vec<u8>) -> Result<usize, Error>

Reads all bytes until EOF in this source, placing them into buf.

fn read_to_string(&mut self, buf: &mut String) -> Result<usize, Error>

Reads all bytes until EOF in this source, appending them to buf.

fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), Error>

Reads the exact number of bytes required to fill buf.

fn read_buf(&mut self, buf: BorrowedCursor<'_>) -> Result<(), Error>

🔬This is a nightly-only experimental API. (read_buf)

Pull some bytes from this source into the specified buffer.

fn read_buf_exact(&mut self, cursor: BorrowedCursor<'_>) -> Result<(), Error>

🔬This is a nightly-only experimental API. (read_buf)

Reads the exact number of bytes required to fill cursor.

fn by_ref(&mut self) -> &mut Self

where Self: Sized,

Creates a “by reference” adaptor for this instance of Read.

fn bytes(self) -> Bytes<Self>

where Self: Sized,

Transforms this Read instance to an Iterator over its bytes.

fn chain<R>(self, next: R) -> Chain<Self, R>

where R: Read, Self: Sized,

Creates an adapter which will chain this stream with another.

fn take(self, limit: u64) -> Take<Self>

where Self: Sized,

Creates an adapter which will read at most limit bytes from it.

impl<S: Storage + ?Sized> RingBuffer for LocalRb<S>

unsafe fn hold_read(&self, flag: bool) -> bool

Tell whether read end of the ring buffer is held by consumer or not.

unsafe fn hold_write(&self, flag: bool) -> bool

Tell whether write end of the ring buffer is held by producer or not.

fn push_overwrite(&mut self, elem: Self::Item) -> Option<Self::Item>

Pushes an item to the ring buffer overwriting the latest item if the buffer is full.

fn push_iter_overwrite<I: Iterator<Item = Self::Item>>(&mut self, iter: I)

Appends items from an iterator to the ring buffer.

fn push_slice_overwrite(&mut self, elems: &[Self::Item])

where Self::Item: Copy,

Appends items from slice to the ring buffer overwriting existing items in the ring buffer.

impl<S: Storage + ?Sized> Split for Box<LocalRb<S>>

type Prod = Direct<Rc<LocalRb<S>>, true, false>

Producer type.

type Cons = Direct<Rc<LocalRb<S>>, false, true>

Consumer type.

fn split(self) -> (Self::Prod, Self::Cons)

Perform splitting.

impl<S: Storage> Split for LocalRb<S>

type Prod = Direct<Rc<LocalRb<S>>, true, false>

Producer type.

type Cons = Direct<Rc<LocalRb<S>>, false, true>

Consumer type.

fn split(self) -> (Self::Prod, Self::Cons)

Perform splitting.

impl<S: Storage + ?Sized> SplitRef for LocalRb<S>

type RefProd<'a> = Direct<&'a LocalRb<S>, true, false> where Self: 'a

Ref producer type.

type RefCons<'a> = Direct<&'a LocalRb<S>, false, true> where Self: 'a

Ref consumer type.

fn split_ref(&mut self) -> (Self::RefProd<'_>, Self::RefCons<'_>)

Perform splitting by reference.

impl<S: Storage> Write for LocalRb<S>

where Self: Producer<Item = u8>,

fn write(&mut self, buf: &[u8]) -> Result<usize>

Writes a buffer into this writer, returning how many bytes were written.

fn flush(&mut self) -> Result<()>

Flushes this output stream, ensuring that all intermediately buffered contents reach their destination.

fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> Result<usize, Error>

Like write, except that it writes from a slice of buffers.

fn is_write_vectored(&self) -> bool

🔬This is a nightly-only experimental API. (can_vector)

Determines if this Writer has an efficient write_vectored implementation.

fn write_all(&mut self, buf: &[u8]) -> Result<(), Error>

Attempts to write an entire buffer into this writer.

fn write_all_vectored(&mut self, bufs: &mut [IoSlice<'_>]) -> Result<(), Error>

🔬This is a nightly-only experimental API. (write_all_vectored)

Attempts to write multiple buffers into this writer.

fn write_fmt(&mut self, fmt: Arguments<'_>) -> Result<(), Error>

Writes a formatted string into this writer, returning any error encountered.

fn by_ref(&mut self) -> &mut Self

where Self: Sized,

Creates a “by reference” adapter for this instance of Write.

impl<S: Storage> Write for LocalRb<S>

where Self: Producer<Item = u8>,

fn write_str(&mut self, s: &str) -> Result

Writes a string slice into this writer, returning whether the write succeeded.

fn write_char(&mut self, c: char) -> Result<(), Error>

Writes a char into this writer, returning whether the write succeeded.

fn write_fmt(&mut self, args: Arguments<'_>) -> Result<(), Error>

Glue for usage of the write! macro with implementors of this trait.