Struct sgx_tstd::io::BufReader

pub struct BufReader<R> { /* fields omitted */ }

The BufReader struct adds buffering to any reader.

It can be excessively inefficient to work directly with a Read instance. For example, every call to read on TcpStream results in a system call. A BufReader performs large, infrequent reads on the underlying Read and maintains an in-memory buffer of the results.

Methods

impl<R: Read> BufReader<R>

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

Creates a new BufReader with a default buffer capacity.

pub fn with_capacity(cap: usize, inner: R) -> BufReader<R>

Creates a new BufReader with the specified buffer capacity.

pub fn get_ref(&self) -> &R

Gets a reference to the underlying reader.

It is inadvisable to directly read from the underlying reader.

pub fn get_mut(&mut self) -> &mut R

Gets a mutable reference to the underlying reader.

It is inadvisable to directly read from the underlying reader.

pub fn is_empty(&self) -> bool

Returns true if there are no bytes in the internal buffer.

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

Returns a reference to the internally buffered data.

Unlike fill_buf, this will not attempt to fill the buffer if it is empty.

pub fn into_inner(self) -> R

Unwraps this BufReader, returning the underlying reader.

Note that any leftover data in the internal buffer is lost.

impl<R: Seek> BufReader<R>

pub fn seek_relative(&mut self, offset: i64) -> Result<()>

Seeks relative to the current position. If the new position lies within the buffer, the buffer will not be flushed, allowing for more efficient seeks. This method does not return the location of the underlying reader, so the caller must track this information themselves if it is required.

Trait Implementations

impl<R: Read> Read for BufReader<R>

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.

unsafe fn initializer(&self) -> Initializer

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

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

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

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

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

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

Read the exact number of bytes required to fill buf.

fn by_ref(&mut self) -> &mut Self where     Self: Sized,

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

Important traits for Bytes<R>

impl<R: Read> Iterator for Bytes<R> type Item = Result<u8>;

fn bytes(self) -> Bytes<Self> where     Self: Sized,

Transforms this Read instance to an Iterator over its bytes.

Important traits for Chars<R>

impl<R: Read> Iterator for Chars<R> type Item = Result<char, CharsError>;

fn chars(self) -> Chars<Self> where     Self: Sized,

Transforms this Read instance to an Iterator over chars.

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

Creates an adaptor which will chain this stream with another.

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

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

impl<R: Read> BufRead for BufReader<R>

fn fill_buf(&mut self) -> Result<&[u8]>

Fills the internal buffer of this object, returning the buffer contents.

fn consume(&mut self, amt: usize)

Tells this buffer that amt bytes have been consumed from the buffer, so they should no longer be returned in calls to read.

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

Read all bytes into buf until the delimiter byte or EOF is reached.

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

Read all bytes until a newline (the 0xA byte) is reached, and append them to the provided buffer.

Important traits for Split<B>

impl<B: BufRead> Iterator for Split<B> type Item = Result<Vec<u8>>;

fn split(self, byte: u8) -> Split<Self> where     Self: Sized,

Returns an iterator over the contents of this reader split on the byte byte.

Important traits for Lines<B>

impl<B: BufRead> Iterator for Lines<B> type Item = Result<String>;

fn lines(self) -> Lines<Self> where     Self: Sized,

Returns an iterator over the lines of this reader.

impl<R> Debug for BufReader<R> where     R: Debug,

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

Formats the value using the given formatter.

impl<R: Seek> Seek for BufReader<R>

fn seek(&mut self, pos: SeekFrom) -> Result<u64>

Seek to an offset, in bytes, in the underlying reader.

The position used for seeking with SeekFrom::Current(_) is the position the underlying reader would be at if the BufReader had no internal buffer.

Seeking always discards the internal buffer, even if the seek position would otherwise fall within it. This guarantees that calling .into_inner() immediately after a seek yields the underlying reader at the same position.

To seek without discarding the internal buffer, use seek_relative.

See std::io::Seek for more details.

Note: In the edge case where you're seeking with SeekFrom::Current(n) where n minus the internal buffer length overflows an i64, two seeks will be performed instead of one. If the second seek returns Err, the underlying reader will be left at the same position it would have if you called seek with SeekFrom::Current(0).