Struct buffered_reader::Dup

pub struct Dup<'a, C> { /* fields omitted */ }

Duplicates the underlying BufferedReader without consuming any of the data.

Note: this will likely cause the underlying stream to buffer as much data as you read. Thus, it should only be used for peeking at the underlying BufferedReader.

Methods

impl<'a> Dup<'a, ()>

pub fn new(reader: Box<dyn BufferedReader<()> + 'a>) -> Self

Instantiates a new Dup buffered reader.

reader is the BufferedReader to duplicate.

impl<'a, C> Dup<'a, C>

pub fn with_cookie(reader: Box<dyn BufferedReader<C> + 'a>, cookie: C) -> Self

Like new(), but uses a cookie.

The cookie can be retrieved using the cookie_ref and cookie_mut methods, and set using the cookie_set method.

pub fn total_out(&self) -> usize

Returns the number of bytes that this reader has consumed.

pub fn rewind(&mut self)

Resets the cursor to the beginning of the stream.

Trait Implementations

impl<'a, C> BufferedReader<C> for Dup<'a, C>

fn buffer(&self) -> &[u8]

Returns a reference to the internal buffer.

fn data(&mut self, amount: usize) -> Result<&[u8], Error>

Ensures that the internal buffer has at least amount bytes of data, and returns it.

fn consume(&mut self, amount: usize) -> &[u8]

Consumes some of the data.

fn data_consume(&mut self, amount: usize) -> Result<&[u8], Error>

A convenience function that combines data() and consume().

fn data_consume_hard(&mut self, amount: usize) -> Result<&[u8], Error>

A convenience function that effectively combines data_hard() and consume().

fn get_mut(&mut self) -> Option<&mut dyn BufferedReader<C>>

Returns a mutable reference to the inner BufferedReader, if any.

fn get_ref(&self) -> Option<&dyn BufferedReader<C>>

Returns a reference to the inner BufferedReader, if any.

fn into_inner<'b>(self: Box<Self>) -> Option<Box<dyn BufferedReader<C> + 'b>> where
    Self: 'b, 

Returns the underlying reader, if any.

fn cookie_set(&mut self, cookie: C) -> C

Sets the BufferedReader's cookie and returns the old value.

fn cookie_ref(&self) -> &C

Returns a reference to the BufferedReader's cookie.

fn cookie_mut(&mut self) -> &mut C

Returns a mutable reference to the BufferedReader's cookie.

fn data_hard(&mut self, amount: usize) -> Result<&[u8], Error>

Like data(), but returns an error if there is not at least amount bytes available.

fn data_eof(&mut self) -> Result<&[u8], Error>

Returns all of the data until EOF. Like data(), this does not actually consume the data that is read.

fn eof(&mut self) -> bool

Checks whether the end of the stream is reached.

fn consummated(&mut self) -> bool

Checks whether this reader is consummated.

fn read_be_u16(&mut self) -> Result<u16, Error>

A convenience function for reading a 16-bit unsigned integer in big endian format.

fn read_be_u32(&mut self) -> Result<u32, Error>

A convenience function for reading a 32-bit unsigned integer in big endian format.

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

Reads until either terminal is encountered or EOF.

fn drop_until(&mut self, terminals: &[u8]) -> Result<usize, Error>

Discards the input until one of the bytes in terminals is encountered.

fn drop_through(
    &mut self,
    terminals: &[u8],
    match_eof: bool
) -> Result<(Option<u8>, usize), Error>

Discards the input until one of the bytes in terminals is encountered.

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

Like data_consume_hard(), but returns the data in a caller-owned buffer.

fn steal_eof(&mut self) -> Result<Vec<u8>, Error>

Like steal(), but instead of stealing a fixed number of bytes, steals all of the data until the end of file.

fn drop_eof(&mut self) -> Result<bool, Error>

Like steal_eof(), but instead of returning the data, the data is discarded.

impl<'a, C> Display for Dup<'a, C>

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<'a, C> Debug for Dup<'a, C>

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<'a, C> Read for Dup<'a, C>

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

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.

unsafe fn initializer(&self) -> Initializer

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

Determines if this Reader can work with buffers of uninitialized memory.

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 by_ref(&mut self) -> &mut Self

Creates a "by reference" adaptor for this instance of Read.

fn bytes(self) -> Bytes<Self>

Transforms this Read instance to an [Iterator] over its bytes.

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

Creates an adaptor which will chain this stream with another.

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

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