diff options
Diffstat (limited to 'third_party/rust/flate2/src/zlib')
| -rw-r--r-- | third_party/rust/flate2/src/zlib/bufread.rs | 233 | ||||
| -rw-r--r-- | third_party/rust/flate2/src/zlib/mod.rs | 159 | ||||
| -rw-r--r-- | third_party/rust/flate2/src/zlib/read.rs | 240 | ||||
| -rw-r--r-- | third_party/rust/flate2/src/zlib/write.rs | 321 |
4 files changed, 953 insertions, 0 deletions
diff --git a/third_party/rust/flate2/src/zlib/bufread.rs b/third_party/rust/flate2/src/zlib/bufread.rs new file mode 100644 index 0000000000..f1d3231651 --- /dev/null +++ b/third_party/rust/flate2/src/zlib/bufread.rs @@ -0,0 +1,233 @@ +use std::io; +use std::io::prelude::*; +use std::mem; + +use crate::zio; +use crate::{Compress, Decompress}; + +/// A ZLIB encoder, or compressor. +/// +/// This structure consumes a [`BufRead`] interface, reading uncompressed data +/// from the underlying reader, and emitting compressed data. +/// +/// [`BufRead`]: https://doc.rust-lang.org/std/io/trait.BufRead.html +/// +/// # Examples +/// +/// ``` +/// use std::io::prelude::*; +/// use flate2::Compression; +/// use flate2::bufread::ZlibEncoder; +/// use std::fs::File; +/// use std::io::BufReader; +/// +/// // Use a buffered file to compress contents into a Vec<u8> +/// +/// # fn open_hello_world() -> std::io::Result<Vec<u8>> { +/// let f = File::open("examples/hello_world.txt")?; +/// let b = BufReader::new(f); +/// let mut z = ZlibEncoder::new(b, Compression::fast()); +/// let mut buffer = Vec::new(); +/// z.read_to_end(&mut buffer)?; +/// # Ok(buffer) +/// # } +/// ``` +#[derive(Debug)] +pub struct ZlibEncoder<R> { + obj: R, + data: Compress, +} + +impl<R: BufRead> 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 { + obj: r, + data: Compress::new(level, true), + } + } +} + +pub fn reset_encoder_data<R>(zlib: &mut ZlibEncoder<R>) { + zlib.data.reset() +} + +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. + pub fn reset(&mut self, r: R) -> R { + reset_encoder_data(self); + mem::replace(&mut self.obj, r) + } + + /// Acquires a reference to the underlying reader + pub fn get_ref(&self) -> &R { + &self.obj + } + + /// 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 { + &mut self.obj + } + + /// Consumes this encoder, returning the underlying reader. + pub fn into_inner(self) -> R { + self.obj + } + + /// 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.data.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.data.total_out() + } +} + +impl<R: BufRead> Read for ZlibEncoder<R> { + fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> { + zio::read(&mut self.obj, &mut self.data, buf) + } +} + +impl<R: BufRead + Write> Write for ZlibEncoder<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 ZLIB decoder, or decompressor. +/// +/// This structure consumes a [`BufRead`] interface, reading compressed data +/// from the underlying reader, and emitting uncompressed data. +/// +/// [`BufRead`]: https://doc.rust-lang.org/std/io/trait.BufRead.html +/// +/// # Examples +/// +/// ``` +/// use std::io::prelude::*; +/// use std::io; +/// # use flate2::Compression; +/// # use flate2::write::ZlibEncoder; +/// use flate2::bufread::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_bufreader(bytes).unwrap()); +/// # } +/// # +/// // Uncompresses a Zlib Encoded vector of bytes and returns a string or error +/// // Here &[u8] implements BufRead +/// +/// fn decode_bufreader(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> { + obj: R, + data: Decompress, +} + +impl<R: BufRead> ZlibDecoder<R> { + /// Creates a new decoder which will decompress data read from the given + /// stream. + pub fn new(r: R) -> ZlibDecoder<R> { + ZlibDecoder { + obj: r, + data: Decompress::new(true), + } + } +} + +pub fn reset_decoder_data<R>(zlib: &mut ZlibDecoder<R>) { + zlib.data = Decompress::new(true); +} + +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. + pub fn reset(&mut self, r: R) -> R { + reset_decoder_data(self); + mem::replace(&mut self.obj, r) + } + + /// Acquires a reference to the underlying stream + pub fn get_ref(&self) -> &R { + &self.obj + } + + /// 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 { + &mut self.obj + } + + /// Consumes this decoder, returning the underlying reader. + pub fn into_inner(self) -> R { + self.obj + } + + /// 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.data.total_in() + } + + /// Returns the number of bytes that the decompressor has produced. + pub fn total_out(&self) -> u64 { + self.data.total_out() + } +} + +impl<R: BufRead> Read for ZlibDecoder<R> { + fn read(&mut self, into: &mut [u8]) -> io::Result<usize> { + zio::read(&mut self.obj, &mut self.data, into) + } +} + +impl<R: BufRead + 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() + } +} diff --git a/third_party/rust/flate2/src/zlib/mod.rs b/third_party/rust/flate2/src/zlib/mod.rs new file mode 100644 index 0000000000..9d3de95c54 --- /dev/null +++ b/third_party/rust/flate2/src/zlib/mod.rs @@ -0,0 +1,159 @@ +pub mod bufread; +pub mod read; +pub mod write; + +#[cfg(test)] +mod tests { + use std::io; + use std::io::prelude::*; + + use rand::{thread_rng, Rng}; + + use crate::zlib::{read, write}; + use crate::Compression; + + #[test] + fn roundtrip() { + let mut real = Vec::new(); + let mut w = write::ZlibEncoder::new(Vec::new(), Compression::default()); + let v = crate::random_bytes().take(1024).collect::<Vec<_>>(); + for _ in 0..200 { + let to_write = &v[..thread_rng().gen_range(0..v.len())]; + real.extend(to_write.iter().map(|x| *x)); + w.write_all(to_write).unwrap(); + } + let result = w.finish().unwrap(); + let mut r = read::ZlibDecoder::new(&result[..]); + let mut ret = Vec::new(); + r.read_to_end(&mut ret).unwrap(); + assert!(ret == real); + } + + #[test] + fn drop_writes() { + let mut data = Vec::new(); + write::ZlibEncoder::new(&mut data, Compression::default()) + .write_all(b"foo") + .unwrap(); + let mut r = read::ZlibDecoder::new(&data[..]); + let mut ret = Vec::new(); + r.read_to_end(&mut ret).unwrap(); + assert!(ret == b"foo"); + } + + #[test] + fn total_in() { + let mut real = Vec::new(); + let mut w = write::ZlibEncoder::new(Vec::new(), Compression::default()); + let v = crate::random_bytes().take(1024).collect::<Vec<_>>(); + for _ in 0..200 { + let to_write = &v[..thread_rng().gen_range(0..v.len())]; + real.extend(to_write.iter().map(|x| *x)); + w.write_all(to_write).unwrap(); + } + let mut result = w.finish().unwrap(); + + let result_len = result.len(); + + for _ in 0..200 { + result.extend(v.iter().map(|x| *x)); + } + + let mut r = read::ZlibDecoder::new(&result[..]); + let mut ret = Vec::new(); + r.read_to_end(&mut ret).unwrap(); + assert!(ret == real); + assert_eq!(r.total_in(), result_len as u64); + } + + #[test] + fn roundtrip2() { + let v = crate::random_bytes().take(1024 * 1024).collect::<Vec<_>>(); + let mut r = read::ZlibDecoder::new(read::ZlibEncoder::new(&v[..], Compression::default())); + let mut ret = Vec::new(); + r.read_to_end(&mut ret).unwrap(); + assert_eq!(ret, v); + } + + #[test] + fn roundtrip3() { + let v = crate::random_bytes().take(1024 * 1024).collect::<Vec<_>>(); + let mut w = + write::ZlibEncoder::new(write::ZlibDecoder::new(Vec::new()), Compression::default()); + w.write_all(&v).unwrap(); + let w = w.finish().unwrap().finish().unwrap(); + assert!(w == v); + } + + #[test] + fn reset_decoder() { + let v = crate::random_bytes().take(1024 * 1024).collect::<Vec<_>>(); + let mut w = write::ZlibEncoder::new(Vec::new(), Compression::default()); + w.write_all(&v).unwrap(); + let data = w.finish().unwrap(); + + { + let (mut a, mut b, mut c) = (Vec::new(), Vec::new(), Vec::new()); + let mut r = read::ZlibDecoder::new(&data[..]); + r.read_to_end(&mut a).unwrap(); + r.reset(&data); + r.read_to_end(&mut b).unwrap(); + + let mut r = read::ZlibDecoder::new(&data[..]); + r.read_to_end(&mut c).unwrap(); + assert!(a == b && b == c && c == v); + } + + { + let mut w = write::ZlibDecoder::new(Vec::new()); + w.write_all(&data).unwrap(); + let a = w.reset(Vec::new()).unwrap(); + w.write_all(&data).unwrap(); + let b = w.finish().unwrap(); + + let mut w = write::ZlibDecoder::new(Vec::new()); + w.write_all(&data).unwrap(); + let c = w.finish().unwrap(); + assert!(a == b && b == c && c == v); + } + } + + #[test] + fn bad_input() { + // regress tests: previously caused a panic on drop + let mut out: Vec<u8> = Vec::new(); + let data: Vec<u8> = (0..255).cycle().take(1024).collect(); + let mut w = write::ZlibDecoder::new(&mut out); + match w.write_all(&data[..]) { + Ok(_) => panic!("Expected an error to be returned!"), + Err(e) => assert_eq!(e.kind(), io::ErrorKind::InvalidInput), + } + } + + #[test] + fn qc_reader() { + ::quickcheck::quickcheck(test as fn(_) -> _); + + fn test(v: Vec<u8>) -> bool { + let mut r = + read::ZlibDecoder::new(read::ZlibEncoder::new(&v[..], Compression::default())); + let mut v2 = Vec::new(); + r.read_to_end(&mut v2).unwrap(); + v == v2 + } + } + + #[test] + fn qc_writer() { + ::quickcheck::quickcheck(test as fn(_) -> _); + + fn test(v: Vec<u8>) -> bool { + let mut w = write::ZlibEncoder::new( + write::ZlibDecoder::new(Vec::new()), + Compression::default(), + ); + w.write_all(&v).unwrap(); + v == w.finish().unwrap().finish().unwrap() + } + } +} diff --git a/third_party/rust/flate2/src/zlib/read.rs b/third_party/rust/flate2/src/zlib/read.rs new file mode 100644 index 0000000000..5094931665 --- /dev/null +++ b/third_party/rust/flate2/src/zlib/read.rs @@ -0,0 +1,240 @@ +use std::io; +use std::io::prelude::*; + +use super::bufread; +use crate::bufreader::BufReader; + +/// A ZLIB encoder, or compressor. +/// +/// This structure implements a [`Read`] interface and will read uncompressed +/// data from an underlying stream and emit a stream of 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 = [0;50]; +/// let byte_count = z.read(&mut buffer)?; +/// # Ok(buffer[0..byte_count].to_vec()) +/// # } +/// ``` +#[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), + } + } +} + +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 and takes a stream of +/// compressed data as input, providing the decompressed data when read from. +/// +/// [`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]) + } + + /// Same as `new`, but the intermediate buffer for data is specified. + /// + /// 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)), + } + } +} + +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 encoder 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() + } +} diff --git a/third_party/rust/flate2/src/zlib/write.rs b/third_party/rust/flate2/src/zlib/write.rs new file mode 100644 index 0000000000..c67181402b --- /dev/null +++ b/third_party/rust/flate2/src/zlib/write.rs @@ -0,0 +1,321 @@ +use std::io; +use std::io::prelude::*; + +use crate::zio; +use crate::{Compress, Decompress}; + +/// A ZLIB encoder, or compressor. +/// +/// This structure implements a [`Write`] interface and takes a stream of +/// uncompressed data, writing the compressed data to the wrapped writer. +/// +/// [`Write`]: https://doc.rust-lang.org/std/io/trait.Write.html +/// +/// # Examples +/// +/// ``` +/// use std::io::prelude::*; +/// use flate2::Compression; +/// use flate2::write::ZlibEncoder; +/// +/// // Vec<u8> implements Write, assigning the compressed bytes of sample string +/// +/// # fn zlib_encoding() -> std::io::Result<()> { +/// let mut e = ZlibEncoder::new(Vec::new(), Compression::default()); +/// e.write_all(b"Hello World")?; +/// let compressed = e.finish()?; +/// # Ok(()) +/// # } +/// ``` +#[derive(Debug)] +pub struct ZlibEncoder<W: Write> { + inner: zio::Writer<W, Compress>, +} + +impl<W: Write> ZlibEncoder<W> { + /// Creates a new encoder which will write compressed data to the stream + /// given at the given compression level. + /// + /// When this encoder is dropped or unwrapped the final pieces of data will + /// be flushed. + pub fn new(w: W, level: crate::Compression) -> ZlibEncoder<W> { + ZlibEncoder { + inner: zio::Writer::new(w, Compress::new(level, true)), + } + } + + /// Acquires a reference to the underlying writer. + pub fn get_ref(&self) -> &W { + self.inner.get_ref() + } + + /// Acquires a mutable reference to the underlying writer. + /// + /// Note that mutating the output/input state of the stream may corrupt this + /// object, so care must be taken when using this method. + pub fn get_mut(&mut self) -> &mut W { + self.inner.get_mut() + } + + /// Resets the state of this encoder entirely, swapping out the output + /// stream for another. + /// + /// This function will finish encoding the current stream into the current + /// output stream before swapping out the two output streams. + /// + /// After the current stream has been finished, this will reset the internal + /// state of this encoder and replace the output stream with the one + /// provided, returning the previous output stream. Future data written to + /// this encoder will be the compressed into the stream `w` provided. + /// + /// # Errors + /// + /// This function will perform I/O to complete this stream, and any I/O + /// errors which occur will be returned from this function. + pub fn reset(&mut self, w: W) -> io::Result<W> { + self.inner.finish()?; + self.inner.data.reset(); + Ok(self.inner.replace(w)) + } + + /// Attempt to finish this output stream, writing out final chunks of data. + /// + /// Note that this function can only be used once data has finished being + /// written to the output stream. After this function is called then further + /// calls to `write` may result in a panic. + /// + /// # Panics + /// + /// Attempts to write data to this stream may result in a panic after this + /// function is called. + /// + /// # Errors + /// + /// This function will perform I/O to complete this stream, and any I/O + /// errors which occur will be returned from this function. + pub fn try_finish(&mut self) -> io::Result<()> { + self.inner.finish() + } + + /// Consumes this encoder, flushing the output stream. + /// + /// This will flush the underlying data stream, close off the compressed + /// stream and, if successful, return the contained writer. + /// + /// Note that this function may not be suitable to call in a situation where + /// the underlying stream is an asynchronous I/O stream. To finish a stream + /// the `try_finish` (or `shutdown`) method should be used instead. To + /// re-acquire ownership of a stream it is safe to call this method after + /// `try_finish` or `shutdown` has returned `Ok`. + /// + /// # Errors + /// + /// This function will perform I/O to complete this stream, and any I/O + /// errors which occur will be returned from this function. + pub fn finish(mut self) -> io::Result<W> { + self.inner.finish()?; + Ok(self.inner.take_inner()) + } + + /// Consumes this encoder, flushing the output stream. + /// + /// This will flush the underlying data stream and then return the contained + /// writer if the flush succeeded. + /// The compressed stream will not closed but only flushed. This + /// means that obtained byte array can by extended by another deflated + /// stream. To close the stream add the two bytes 0x3 and 0x0. + /// + /// # Errors + /// + /// This function will perform I/O to complete this stream, and any I/O + /// errors which occur will be returned from this function. + pub fn flush_finish(mut self) -> io::Result<W> { + self.inner.flush()?; + Ok(self.inner.take_inner()) + } + + /// Returns the number of bytes that have been written to this compressor. + /// + /// Note that not all bytes written to this object may be accounted for, + /// there may still be some active buffering. + pub fn total_in(&self) -> u64 { + self.inner.data.total_in() + } + + /// Returns the number of bytes that the compressor has produced. + /// + /// Note that not all bytes may have been written yet, some may still be + /// buffered. + pub fn total_out(&self) -> u64 { + self.inner.data.total_out() + } +} + +impl<W: Write> Write for ZlibEncoder<W> { + fn write(&mut self, buf: &[u8]) -> io::Result<usize> { + self.inner.write(buf) + } + + fn flush(&mut self) -> io::Result<()> { + self.inner.flush() + } +} + +impl<W: Read + Write> Read for ZlibEncoder<W> { + fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> { + self.get_mut().read(buf) + } +} + +/// A ZLIB decoder, or decompressor. +/// +/// This structure implements a [`Write`] and will emit a stream of decompressed +/// data when fed a stream of compressed data. +/// +/// [`Write`]: https://doc.rust-lang.org/std/io/trait.Write.html +/// +/// # Examples +/// +/// ``` +/// use std::io::prelude::*; +/// use std::io; +/// # use flate2::Compression; +/// # use flate2::write::ZlibEncoder; +/// use flate2::write::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 Vec<u8> implements Write +/// +/// fn decode_reader(bytes: Vec<u8>) -> io::Result<String> { +/// let mut writer = Vec::new(); +/// let mut z = ZlibDecoder::new(writer); +/// z.write_all(&bytes[..])?; +/// writer = z.finish()?; +/// let return_string = String::from_utf8(writer).expect("String parsing error"); +/// Ok(return_string) +/// } +/// ``` +#[derive(Debug)] +pub struct ZlibDecoder<W: Write> { + inner: zio::Writer<W, Decompress>, +} + +impl<W: Write> ZlibDecoder<W> { + /// Creates a new decoder which will write uncompressed data to the stream. + /// + /// When this decoder is dropped or unwrapped the final pieces of data will + /// be flushed. + pub fn new(w: W) -> ZlibDecoder<W> { + ZlibDecoder { + inner: zio::Writer::new(w, Decompress::new(true)), + } + } + + /// Acquires a reference to the underlying writer. + pub fn get_ref(&self) -> &W { + self.inner.get_ref() + } + + /// Acquires a mutable reference to the underlying writer. + /// + /// Note that mutating the output/input state of the stream may corrupt this + /// object, so care must be taken when using this method. + pub fn get_mut(&mut self) -> &mut W { + self.inner.get_mut() + } + + /// Resets the state of this decoder entirely, swapping out the output + /// stream for another. + /// + /// This will reset the internal state of this decoder and replace the + /// output stream with the one provided, returning the previous output + /// stream. Future data written to this decoder will be decompressed into + /// the output stream `w`. + /// + /// # Errors + /// + /// This function will perform I/O to complete this stream, and any I/O + /// errors which occur will be returned from this function. + pub fn reset(&mut self, w: W) -> io::Result<W> { + self.inner.finish()?; + self.inner.data = Decompress::new(true); + Ok(self.inner.replace(w)) + } + + /// Attempt to finish this output stream, writing out final chunks of data. + /// + /// Note that this function can only be used once data has finished being + /// written to the output stream. After this function is called then further + /// calls to `write` may result in a panic. + /// + /// # Panics + /// + /// Attempts to write data to this stream may result in a panic after this + /// function is called. + /// + /// # Errors + /// + /// This function will perform I/O to complete this stream, and any I/O + /// errors which occur will be returned from this function. + pub fn try_finish(&mut self) -> io::Result<()> { + self.inner.finish() + } + + /// Consumes this encoder, flushing the output stream. + /// + /// This will flush the underlying data stream and then return the contained + /// writer if the flush succeeded. + /// + /// Note that this function may not be suitable to call in a situation where + /// the underlying stream is an asynchronous I/O stream. To finish a stream + /// the `try_finish` (or `shutdown`) method should be used instead. To + /// re-acquire ownership of a stream it is safe to call this method after + /// `try_finish` or `shutdown` has returned `Ok`. + /// + /// # Errors + /// + /// This function will perform I/O to complete this stream, and any I/O + /// errors which occur will be returned from this function. + pub fn finish(mut self) -> io::Result<W> { + self.inner.finish()?; + Ok(self.inner.take_inner()) + } + + /// Returns the number of bytes that the decompressor has consumed for + /// decompression. + /// + /// Note that this will likely be smaller than the number of bytes + /// successfully written to this stream due to internal buffering. + pub fn total_in(&self) -> u64 { + self.inner.data.total_in() + } + + /// Returns the number of bytes that the decompressor has written to its + /// output stream. + pub fn total_out(&self) -> u64 { + self.inner.data.total_out() + } +} + +impl<W: Write> Write for ZlibDecoder<W> { + fn write(&mut self, buf: &[u8]) -> io::Result<usize> { + self.inner.write(buf) + } + + fn flush(&mut self) -> io::Result<()> { + self.inner.flush() + } +} + +impl<W: Read + Write> Read for ZlibDecoder<W> { + fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> { + self.inner.get_mut().read(buf) + } +} |