Struct flate2::bufread::MultiGzDecoder

pub struct MultiGzDecoder<R>(_);

A gzip streaming decoder that decodes all members of a multistream

A gzip member consists of a header, compressed data and a trailer. The gzip specification, however, allows multiple gzip members to be joined in a single stream. MultiGzDecoder will decode all consecutive members while GzDecoder will only decompress the first gzip member. The multistream format is commonly used in bioinformatics, for example when using the BGZF compressed data.

This structure exposes a BufRead interface that will consume all gzip members from the underlying reader and emit uncompressed data.

Examples

use std::io::prelude::*;
use std::io;
use flate2::bufread::MultiGzDecoder;

// Uncompresses a Gz Encoded vector of bytes and returns a string or error
// Here &[u8] implements BufRead

fn decode_reader(bytes: Vec<u8>) -> io::Result<String> {
   let mut gz = MultiGzDecoder::new(&bytes[..]);
   let mut s = String::new();
   gz.read_to_string(&mut s)?;
   Ok(s)
}

Implementations

impl<R: BufRead> MultiGzDecoder<R>

pub fn new(r: R) -> MultiGzDecoder<R>

Creates a new decoder from the given reader, immediately parsing the (first) gzip header. If the gzip stream contains multiple members all will be decoded.

impl<R> MultiGzDecoder<R>

pub fn header(&self) -> Option<&GzHeader>

Returns the current header associated with this stream, if it's valid

pub fn get_ref(&self) -> &R

Acquires a reference to the underlying reader.

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

Acquires a mutable reference to the underlying stream.

Note that mutation of the stream may result in surprising results if this encoder is continued to be used.

pub fn into_inner(self) -> R

Consumes this decoder, returning the underlying reader.

Trait Implementations

impl<R: Debug> Debug for MultiGzDecoder<R>

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

Formats the value using the given formatter.

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

fn read(&mut self, into: &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.

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.

impl<R: BufRead + Write> Write for MultiGzDecoder<R>

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

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

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

Flush 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 Writeer 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

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