/rust/registry/src/index.crates.io-1949cf8c6b5b557f/flate2-1.0.28/src/zlib/read.rs

Source
use std::io;
use std::io::prelude::*;

use super::bufread;
use crate::bufreader::BufReader;
use crate::Decompress;

/// A ZLIB encoder, or compressor.
///
/// This structure implements a [`Read`] interface. When read from, it reads
/// uncompressed data from the underlying [`Read`] and provides the compressed data.
///
/// [`Read`]: https://doc.rust-lang.org/std/io/trait.Read.html
///
/// # Examples
///
/// ```
/// use std::io::prelude::*;
/// use flate2::Compression;
/// use flate2::read::ZlibEncoder;
/// use std::fs::File;
///
/// // Open example file and compress the contents using Read interface
///
/// # fn open_hello_world() -> std::io::Result<Vec<u8>> {
/// let f = File::open("examples/hello_world.txt")?;
/// let mut z = ZlibEncoder::new(f, Compression::fast());
/// let mut buffer = Vec::new();
/// z.read_to_end(&mut buffer)?;
/// # Ok(buffer)
/// # }
/// ```
#[derive(Debug)]
pub struct ZlibEncoder<R> {
    inner: bufread::ZlibEncoder<BufReader<R>>,
}

impl<R: Read> ZlibEncoder<R> {
    /// Creates a new encoder which will read uncompressed data from the given
    /// stream and emit the compressed stream.
    pub fn new(r: R, level: crate::Compression) -> ZlibEncoder<R> {
        ZlibEncoder {
            inner: bufread::ZlibEncoder::new(BufReader::new(r), level),
        }
    }

    /// Creates a new encoder with the given `compression` settings which will
    /// read uncompressed data from the given stream `r` and emit the compressed stream.
    pub fn new_with_compress(r: R, compression: crate::Compress) -> ZlibEncoder<R> {
        ZlibEncoder {
            inner: bufread::ZlibEncoder::new_with_compress(BufReader::new(r), compression),
        }
    }
}

impl<R> ZlibEncoder<R> {
    /// Resets the state of this encoder entirely, swapping out the input
    /// stream for another.
    ///
    /// This function will reset the internal state of this encoder and replace
    /// the input stream with the one provided, returning the previous input
    /// stream. Future data read from this encoder will be the compressed
    /// version of `r`'s data.
    ///
    /// Note that there may be currently buffered data when this function is
    /// called, and in that case the buffered data is discarded.
    pub fn reset(&mut self, r: R) -> R {
        super::bufread::reset_encoder_data(&mut self.inner);
        self.inner.get_mut().reset(r)
    }

    /// Acquires a reference to the underlying stream
    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 encoder is continued to be used.
    pub fn get_mut(&mut self) -> &mut R {
        self.inner.get_mut().get_mut()
    }

    /// Consumes this encoder, returning the underlying reader.
    ///
    /// Note that there may be buffered bytes which are not re-acquired as part
    /// of this transition. It's recommended to only call this function after
    /// EOF has been reached.
    pub fn into_inner(self) -> R {
        self.inner.into_inner().into_inner()
    }

    /// Returns the number of bytes that have been read into this compressor.
    ///
    /// Note that not all bytes read from the underlying object may be accounted
    /// for, there may still be some active buffering.
    pub fn total_in(&self) -> u64 {
        self.inner.total_in()
    }

    /// Returns the number of bytes that the compressor has produced.
    ///
    /// Note that not all bytes may have been read yet, some may still be
    /// buffered.
    pub fn total_out(&self) -> u64 {
        self.inner.total_out()
    }
}

impl<R: Read> Read for ZlibEncoder<R> {
    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
        self.inner.read(buf)
    }
}

impl<W: Read + Write> Write for ZlibEncoder<W> {
    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 ZLIB decoder, or decompressor.
///
/// This structure implements a [`Read`] interface. When read from, it reads
/// compressed data from the underlying [`Read`] and provides the uncompressed data.
///
/// [`Read`]: https://doc.rust-lang.org/std/io/trait.Read.html
///
/// # Examples
///
/// ```
/// use std::io::prelude::*;
/// use std::io;
/// # use flate2::Compression;
/// # use flate2::write::ZlibEncoder;
/// use flate2::read::ZlibDecoder;
///
/// # fn main() {
/// # let mut e = ZlibEncoder::new(Vec::new(), Compression::default());
/// # e.write_all(b"Hello World").unwrap();
/// # let bytes = e.finish().unwrap();
/// # println!("{}", decode_reader(bytes).unwrap());
/// # }
/// #
/// // Uncompresses a Zlib 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 z = ZlibDecoder::new(&bytes[..]);
///     let mut s = String::new();
///     z.read_to_string(&mut s)?;
///     Ok(s)
/// }
/// ```
#[derive(Debug)]
pub struct ZlibDecoder<R> {
    inner: bufread::ZlibDecoder<BufReader<R>>,
}

impl<R: Read> ZlibDecoder<R> {
    /// Creates a new decoder which will decompress data read from the given
    /// stream.
    pub fn new(r: R) -> ZlibDecoder<R> {
        ZlibDecoder::new_with_buf(r, vec![0; 32 * 1024])
    }

    /// Creates a new decoder which will decompress data read from the given
    /// stream `r`, using `buf` as backing to speed up reading.
    ///
    /// Note that the specified buffer will only be used up to its current
    /// length. The buffer's capacity will also not grow over time.
    pub fn new_with_buf(r: R, buf: Vec<u8>) -> ZlibDecoder<R> {
        ZlibDecoder {
            inner: bufread::ZlibDecoder::new(BufReader::with_buf(buf, r)),
        }
    }

    /// Creates a new decoder which will decompress data read from the given
    /// stream `r`, along with `decompression` settings.
    pub fn new_with_decompress(r: R, decompression: Decompress) -> ZlibDecoder<R> {
        ZlibDecoder::new_with_decompress_and_buf(r, vec![0; 32 * 1024], decompression)
    }

    /// Creates a new decoder which will decompress data read from the given
    /// stream `r`, using `buf` as backing to speed up reading,
    /// along with `decompression` settings to configure decoder.
    ///
    /// Note that the specified buffer will only be used up to its current
    /// length. The buffer's capacity will also not grow over time.
    pub fn new_with_decompress_and_buf(
        r: R,
        buf: Vec<u8>,
        decompression: Decompress,
    ) -> ZlibDecoder<R> {
        ZlibDecoder {
            inner: bufread::ZlibDecoder::new_with_decompress(
                BufReader::with_buf(buf, r),
                decompression,
            ),
        }
    }
}

impl<R> ZlibDecoder<R> {
    /// Resets the state of this decoder entirely, swapping out the input
    /// stream for another.
    ///
    /// This will reset the internal state of this decoder and replace the
    /// input stream with the one provided, returning the previous input
    /// stream. Future data read from this decoder will be the decompressed
    /// version of `r`'s data.
    ///
    /// Note that there may be currently buffered data when this function is
    /// called, and in that case the buffered data is discarded.
    pub fn reset(&mut self, r: R) -> R {
        super::bufread::reset_decoder_data(&mut self.inner);
        self.inner.get_mut().reset(r)
    }

    /// Acquires a reference to the underlying stream
    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.
    ///
    /// Note that there may be buffered bytes which are not re-acquired as part
    /// of this transition. It's recommended to only call this function after
    /// EOF has been reached.
    pub fn into_inner(self) -> R {
        self.inner.into_inner().into_inner()
    }

    /// Returns the number of bytes that the decompressor has consumed.
    ///
    /// Note that this will likely be smaller than what the decompressor
    /// actually read from the underlying stream due to buffering.
    pub fn total_in(&self) -> u64 {
        self.inner.total_in()
    }

    /// Returns the number of bytes that the decompressor has produced.
    pub fn total_out(&self) -> u64 {
        self.inner.total_out()
    }
}

impl<R: Read> Read for ZlibDecoder<R> {
    fn read(&mut self, into: &mut [u8]) -> io::Result<usize> {
        self.inner.read(into)
    }
}

impl<R: Read + Write> Write for ZlibDecoder<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()
    }
}

Coverage Report

Created: 2025-12-31 06:43

Line	Count	Source
1		use std::io;
2		use std::io::prelude::*;
3
4		use super::bufread;
5		use crate::bufreader::BufReader;
6		use crate::Decompress;
7
8		/// A ZLIB encoder, or compressor.
9		///
10		/// This structure implements a [`Read`] interface. When read from, it reads
11		/// uncompressed data from the underlying [`Read`] and provides the compressed data.
12		///
13		/// [`Read`]: https://doc.rust-lang.org/std/io/trait.Read.html
14		///
15		/// # Examples
16		///
17		/// ```
18		/// use std::io::prelude::*;
19		/// use flate2::Compression;
20		/// use flate2::read::ZlibEncoder;
21		/// use std::fs::File;
22		///
23		/// // Open example file and compress the contents using Read interface
24		///
25		/// # fn open_hello_world() -> std::io::Result<Vec<u8>> {
26		/// let f = File::open("examples/hello_world.txt")?;
27		/// let mut z = ZlibEncoder::new(f, Compression::fast());
28		/// let mut buffer = Vec::new();
29		/// z.read_to_end(&mut buffer)?;
30		/// # Ok(buffer)
31		/// # }
32		/// ```
33		#[derive(Debug)]
34		pub struct ZlibEncoder<R> {
35		inner: bufread::ZlibEncoder<BufReader<R>>,
36		}
37
38		impl<R: Read> ZlibEncoder<R> {
39		/// Creates a new encoder which will read uncompressed data from the given
40		/// stream and emit the compressed stream.
41	0	pub fn new(r: R, level: crate::Compression) -> ZlibEncoder<R> {
42	0	ZlibEncoder {
43	0	inner: bufread::ZlibEncoder::new(BufReader::new(r), level),
44	0	}
45	0	}
46
47		/// Creates a new encoder with the given `compression` settings which will
48		/// read uncompressed data from the given stream `r` and emit the compressed stream.
49	0	pub fn new_with_compress(r: R, compression: crate::Compress) -> ZlibEncoder<R> {
50	0	ZlibEncoder {
51	0	inner: bufread::ZlibEncoder::new_with_compress(BufReader::new(r), compression),
52	0	}
53	0	}
54		}
55
56		impl<R> ZlibEncoder<R> {
57		/// Resets the state of this encoder entirely, swapping out the input
58		/// stream for another.
59		///
60		/// This function will reset the internal state of this encoder and replace
61		/// the input stream with the one provided, returning the previous input
62		/// stream. Future data read from this encoder will be the compressed
63		/// version of `r`'s data.
64		///
65		/// Note that there may be currently buffered data when this function is
66		/// called, and in that case the buffered data is discarded.
67	0	pub fn reset(&mut self, r: R) -> R {
68	0	super::bufread::reset_encoder_data(&mut self.inner);
69	0	self.inner.get_mut().reset(r)
70	0	}
71
72		/// Acquires a reference to the underlying stream
73	0	pub fn get_ref(&self) -> &R {
74	0	self.inner.get_ref().get_ref()
75	0	}
76
77		/// Acquires a mutable reference to the underlying stream
78		///
79		/// Note that mutation of the stream may result in surprising results if
80		/// this encoder is continued to be used.
81	0	pub fn get_mut(&mut self) -> &mut R {
82	0	self.inner.get_mut().get_mut()
83	0	}
84
85		/// Consumes this encoder, returning the underlying reader.
86		///
87		/// Note that there may be buffered bytes which are not re-acquired as part
88		/// of this transition. It's recommended to only call this function after
89		/// EOF has been reached.
90	0	pub fn into_inner(self) -> R {
91	0	self.inner.into_inner().into_inner()
92	0	}
93
94		/// Returns the number of bytes that have been read into this compressor.
95		///
96		/// Note that not all bytes read from the underlying object may be accounted
97		/// for, there may still be some active buffering.
98	0	pub fn total_in(&self) -> u64 {
99	0	self.inner.total_in()
100	0	}
101
102		/// Returns the number of bytes that the compressor has produced.
103		///
104		/// Note that not all bytes may have been read yet, some may still be
105		/// buffered.
106	0	pub fn total_out(&self) -> u64 {
107	0	self.inner.total_out()
108	0	}
109		}
110
111		impl<R: Read> Read for ZlibEncoder<R> {
112	0	fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
113	0	self.inner.read(buf)
114	0	}
115		}
116
117		impl<W: Read + Write> Write for ZlibEncoder<W> {
118	0	fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
119	0	self.get_mut().write(buf)
120	0	}
121
122	0	fn flush(&mut self) -> io::Result<()> {
123	0	self.get_mut().flush()
124	0	}
125		}
126
127		/// A ZLIB decoder, or decompressor.
128		///
129		/// This structure implements a [`Read`] interface. When read from, it reads
130		/// compressed data from the underlying [`Read`] and provides the uncompressed data.
131		///
132		/// [`Read`]: https://doc.rust-lang.org/std/io/trait.Read.html
133		///
134		/// # Examples
135		///
136		/// ```
137		/// use std::io::prelude::*;
138		/// use std::io;
139		/// # use flate2::Compression;
140		/// # use flate2::write::ZlibEncoder;
141		/// use flate2::read::ZlibDecoder;
142		///
143		/// # fn main() {
144		/// # let mut e = ZlibEncoder::new(Vec::new(), Compression::default());
145		/// # e.write_all(b"Hello World").unwrap();
146		/// # let bytes = e.finish().unwrap();
147		/// # println!("{}", decode_reader(bytes).unwrap());
148		/// # }
149		/// #
150		/// // Uncompresses a Zlib Encoded vector of bytes and returns a string or error
151		/// // Here &[u8] implements Read
152		///
153		/// fn decode_reader(bytes: Vec<u8>) -> io::Result<String> {
154		/// let mut z = ZlibDecoder::new(&bytes[..]);
155		/// let mut s = String::new();
156		/// z.read_to_string(&mut s)?;
157		/// Ok(s)
158		/// }
159		/// ```
160		#[derive(Debug)]
161		pub struct ZlibDecoder<R> {
162		inner: bufread::ZlibDecoder<BufReader<R>>,
163		}
164
165		impl<R: Read> ZlibDecoder<R> {
166		/// Creates a new decoder which will decompress data read from the given
167		/// stream.
168	0	pub fn new(r: R) -> ZlibDecoder<R> {
169	0	ZlibDecoder::new_with_buf(r, vec![0; 32 * 1024])
170	0	}
171
172		/// Creates a new decoder which will decompress data read from the given
173		/// stream `r`, using `buf` as backing to speed up reading.
174		///
175		/// Note that the specified buffer will only be used up to its current
176		/// length. The buffer's capacity will also not grow over time.
177	0	pub fn new_with_buf(r: R, buf: Vec<u8>) -> ZlibDecoder<R> {
178	0	ZlibDecoder {
179	0	inner: bufread::ZlibDecoder::new(BufReader::with_buf(buf, r)),
180	0	}
181	0	}
182
183		/// Creates a new decoder which will decompress data read from the given
184		/// stream `r`, along with `decompression` settings.
185	0	pub fn new_with_decompress(r: R, decompression: Decompress) -> ZlibDecoder<R> {
186	0	ZlibDecoder::new_with_decompress_and_buf(r, vec![0; 32 * 1024], decompression)
187	0	}
188
189		/// Creates a new decoder which will decompress data read from the given
190		/// stream `r`, using `buf` as backing to speed up reading,
191		/// along with `decompression` settings to configure decoder.
192		///
193		/// Note that the specified buffer will only be used up to its current
194		/// length. The buffer's capacity will also not grow over time.
195	0	pub fn new_with_decompress_and_buf(
196	0	r: R,
197	0	buf: Vec<u8>,
198	0	decompression: Decompress,
199	0	) -> ZlibDecoder<R> {
200	0	ZlibDecoder {
201	0	inner: bufread::ZlibDecoder::new_with_decompress(
202	0	BufReader::with_buf(buf, r),
203	0	decompression,
204	0	),
205	0	}
206	0	}
207		}
208
209		impl<R> ZlibDecoder<R> {
210		/// Resets the state of this decoder entirely, swapping out the input
211		/// stream for another.
212		///
213		/// This will reset the internal state of this decoder and replace the
214		/// input stream with the one provided, returning the previous input
215		/// stream. Future data read from this decoder will be the decompressed
216		/// version of `r`'s data.
217		///
218		/// Note that there may be currently buffered data when this function is
219		/// called, and in that case the buffered data is discarded.
220	0	pub fn reset(&mut self, r: R) -> R {
221	0	super::bufread::reset_decoder_data(&mut self.inner);
222	0	self.inner.get_mut().reset(r)
223	0	}
224
225		/// Acquires a reference to the underlying stream
226	0	pub fn get_ref(&self) -> &R {
227	0	self.inner.get_ref().get_ref()
228	0	}
229
230		/// Acquires a mutable reference to the underlying stream
231		///
232		/// Note that mutation of the stream may result in surprising results if
233		/// this decoder is continued to be used.
234	0	pub fn get_mut(&mut self) -> &mut R {
235	0	self.inner.get_mut().get_mut()
236	0	}
237
238		/// Consumes this decoder, returning the underlying reader.
239		///
240		/// Note that there may be buffered bytes which are not re-acquired as part
241		/// of this transition. It's recommended to only call this function after
242		/// EOF has been reached.
243	0	pub fn into_inner(self) -> R {
244	0	self.inner.into_inner().into_inner()
245	0	}
246
247		/// Returns the number of bytes that the decompressor has consumed.
248		///
249		/// Note that this will likely be smaller than what the decompressor
250		/// actually read from the underlying stream due to buffering.
251	0	pub fn total_in(&self) -> u64 {
252	0	self.inner.total_in()
253	0	}
254
255		/// Returns the number of bytes that the decompressor has produced.
256	0	pub fn total_out(&self) -> u64 {
257	0	self.inner.total_out()
258	0	}
259		}
260
261		impl<R: Read> Read for ZlibDecoder<R> {
262	0	fn read(&mut self, into: &mut [u8]) -> io::Result<usize> {
263	0	self.inner.read(into)
264	0	}
265		}
266
267		impl<R: Read + Write> Write for ZlibDecoder<R> {
268	0	fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
269	0	self.get_mut().write(buf)
270	0	}
271
272	0	fn flush(&mut self) -> io::Result<()> {
273	0	self.get_mut().flush()
274	0	}
275		}