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use std::io;
use std::io::prelude::*;
use super::bufread;
use super::{GzBuilder, GzHeader};
use crate::bufreader::BufReader;
use crate::Compression;
/// A gzip streaming encoder
///
/// This structure exposes a [`Read`] interface that will read uncompressed data
/// from the underlying reader and expose the compressed version as a [`Read`]
/// interface.
///
///
/// # Examples
///
/// ```
/// use std::io::prelude::*;
/// use std::io;
/// use flate2::Compression;
/// use flate2::read::GzEncoder;
///
/// // Return a vector containing the GZ compressed version of hello world
///
/// fn gzencode_hello_world() -> io::Result<Vec<u8>> {
/// let mut ret_vec = [0;100];
/// let bytestring = b"hello world";
/// let mut gz = GzEncoder::new(&bytestring[..], Compression::fast());
/// let count = gz.read(&mut ret_vec)?;
/// Ok(ret_vec[0..count].to_vec())
/// }
/// ```
#[derive(Debug)]
pub struct GzEncoder<R> {
inner: bufread::GzEncoder<BufReader<R>>,
}
pub fn gz_encoder<R: Read>(inner: bufread::GzEncoder<BufReader<R>>) -> GzEncoder<R> {
GzEncoder { inner }
}
impl<R: Read> GzEncoder<R> {
/// Creates a new encoder which will use the given compression level.
///
/// The encoder is not configured specially for the emitted header. For
/// header configuration, see the `GzBuilder` type.
///
/// The data read from the stream `r` will be compressed and available
/// through the returned reader.
pub fn new(r: R, level: Compression) -> GzEncoder<R> {
GzBuilder::new().read(r, level)
}
}
impl<R> GzEncoder<R> {
/// Acquires a reference to the underlying reader.
pub fn get_ref(&self) -> &R {
self.inner.get_ref().get_ref()
}
/// Acquires a mutable reference to the underlying reader.
///
/// Note that mutation of the reader may result in surprising results if
/// this encoder is continued to be used.
pub fn get_mut(&mut self) -> &mut R {
self.inner.get_mut().get_mut()
}
/// Returns the underlying stream, consuming this encoder
pub fn into_inner(self) -> R {
self.inner.into_inner().into_inner()
}
}
impl<R: Read> Read for GzEncoder<R> {
fn read(&mut self, into: &mut [u8]) -> io::Result<usize> {
self.inner.read(into)
}
}
impl<R: Read + Write> Write for GzEncoder<R> {
fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
self.get_mut().write(buf)
}
fn flush(&mut self) -> io::Result<()> {
self.get_mut().flush()
}
}
/// A gzip streaming decoder
///
/// This structure exposes a [`Read`] interface that will consume compressed
/// data from the underlying reader and emit uncompressed data.
///
///
/// # Examples
///
/// ```
///
/// use std::io::prelude::*;
/// use std::io;
/// # use flate2::Compression;
/// # use flate2::write::GzEncoder;
/// use flate2::read::GzDecoder;
///
/// # fn main() {
/// # let mut e = GzEncoder::new(Vec::new(), Compression::default());
/// # e.write_all(b"Hello World").unwrap();
/// # let bytes = e.finish().unwrap();
/// # println!("{}", decode_reader(bytes).unwrap());
/// # }
/// #
/// // Uncompresses a Gz Encoded vector of bytes and returns a string or error
/// // Here &[u8] implements Read
///
/// fn decode_reader(bytes: Vec<u8>) -> io::Result<String> {
/// let mut gz = GzDecoder::new(&bytes[..]);
/// let mut s = String::new();
/// gz.read_to_string(&mut s)?;
/// Ok(s)
/// }
/// ```
#[derive(Debug)]
pub struct GzDecoder<R> {
inner: bufread::GzDecoder<BufReader<R>>,
}
impl<R: Read> GzDecoder<R> {
/// Creates a new decoder from the given reader, immediately parsing the
/// gzip header.
pub fn new(r: R) -> GzDecoder<R> {
GzDecoder {
inner: bufread::GzDecoder::new(BufReader::new(r)),
}
}
}
impl<R> GzDecoder<R> {
/// Returns the header associated with this stream, if it was valid.
pub fn header(&self) -> Option<&GzHeader> {
self.inner.header()
}
/// Acquires a reference to the underlying reader.
pub fn get_ref(&self) -> &R {
self.inner.get_ref().get_ref()
}
/// Acquires a mutable reference to the underlying stream.
///
/// Note that mutation of the stream may result in surprising results if
/// this decoder is continued to be used.
pub fn get_mut(&mut self) -> &mut R {
self.inner.get_mut().get_mut()
}
/// Consumes this decoder, returning the underlying reader.
pub fn into_inner(self) -> R {
self.inner.into_inner().into_inner()
}
}
impl<R: Read> Read for GzDecoder<R> {
fn read(&mut self, into: &mut [u8]) -> io::Result<usize> {
self.inner.read(into)
}
}
impl<R: Read + Write> Write for GzDecoder<R> {
fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
self.get_mut().write(buf)
}
fn flush(&mut self) -> io::Result<()> {
self.get_mut().flush()
}
}
/// 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](https://tools.ietf.org/html/rfc1952), 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 [`Read`] 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::Compression;
/// # use flate2::write::GzEncoder;
/// use flate2::read::MultiGzDecoder;
///
/// # fn main() {
/// # let mut e = GzEncoder::new(Vec::new(), Compression::default());
/// # e.write_all(b"Hello World").unwrap();
/// # let bytes = e.finish().unwrap();
/// # println!("{}", decode_reader(bytes).unwrap());
/// # }
/// #
/// // Uncompresses a Gz Encoded vector of bytes and returns a string or error
/// // Here &[u8] implements Read
///
/// 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)
/// }
/// ```
#[derive(Debug)]
pub struct MultiGzDecoder<R> {
inner: bufread::MultiGzDecoder<BufReader<R>>,
}
impl<R: Read> 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.
pub fn new(r: R) -> MultiGzDecoder<R> {
MultiGzDecoder {
inner: bufread::MultiGzDecoder::new(BufReader::new(r)),
}
}
}
impl<R> MultiGzDecoder<R> {
/// Returns the current header associated with this stream, if it's valid.
pub fn header(&self) -> Option<&GzHeader> {
self.inner.header()
}
/// Acquires a reference to the underlying reader.
pub fn get_ref(&self) -> &R {
self.inner.get_ref().get_ref()
}
/// Acquires a mutable reference to the underlying stream.
///
/// Note that mutation of the stream may result in surprising results if
/// this decoder is continued to be used.
pub fn get_mut(&mut self) -> &mut R {
self.inner.get_mut().get_mut()
}
/// Consumes this decoder, returning the underlying reader.
pub fn into_inner(self) -> R {
self.inner.into_inner().into_inner()
}
}
impl<R: Read> Read for MultiGzDecoder<R> {
fn read(&mut self, into: &mut [u8]) -> io::Result<usize> {
self.inner.read(into)
}
}
impl<R: Read + Write> Write for MultiGzDecoder<R> {
fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
self.get_mut().write(buf)
}
fn flush(&mut self) -> io::Result<()> {
self.get_mut().flush()
}
}