Struct markable_reader::BufferedMarkableReader

pub struct BufferedMarkableReader<R> { /* private fields */ }

Reads bytes from the inner source with the additional ability to mark a stream at a point that can be returned to later using the a call to reset(). This reader also makes large, infrequent, reads to the underlying reader to increase effeciency read, which ideal when system calls may be involved (e.g., File reads), but offer little benefit with in-memory readers (e.g., vecs).

Whlie the stream is marked all susequent reads are returned as usual, but are also buffered, which is what allows for returning to a previous part of the stream.

Implementations

impl<R> BufferedMarkableReader<R>

where R: Read,

pub fn new(inner: R) -> BufferedMarkableReader<R>

Creates a new reader with an unbounded marked buffer and a buffered reader limited to 8KB by default. The use of this is very similar to that of the std::io::BufReader

Example

pub fn new_with_limited_back_buffer( inner: R, limit: usize ) -> BufferedMarkableReader<R>

Creates a new reader with an limited marked buffer and a buffered reader limited to 8KB by default. Any reads that exceed the provided limit will result in an std::io::Error(ErrorKind::OutOfMemory) error The use of this is very similar to that of the std::io::BufReader

Example

pub fn new_with_capacity_and_limit( inner: R, back_buffer_capacity: usize, reader_buffer_capacity: usize ) -> BufferedMarkableReader<R>

Creates a new reader using the provided capacities as the initial capacity and limit. Any reads that exceed the provided limit will result in an std::io::Error(ErrorKind::OutOfMemory) error The use of this is very similar to that of the std::io::BufReader

Example

pub fn into_inner(self) -> R

Returns the inner reader. IMPORTANT this will likely result in data loss of whatever data has been read into the buffer

Trait Implementations

impl<R> From<R> for BufferedMarkableReader<R>

where R: Read,

fn from(value: R) -> Self

Converts to this type from the input type.

impl<R> MarkerStream for BufferedMarkableReader<R>

fn mark(&mut self) -> usize

Marks the location of the inner stream. From tis point forward reads will be cached. If the stream was marked prior to this call the current buffer will be discarded.

Returns the number of bytes that were discarded as a result of this operation

fn reset(&mut self)

Resets the stream previously marked position, if it is set. If the reader was not previously marked, this has no affect.

fn clear_buffer(&mut self)

Clears the current buffer dropping any values that have been cached.

impl<R> Read for BufferedMarkableReader<R>

where R: Read,

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>

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

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

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

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

Read 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)

Read 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.