1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
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 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()
}
}
|
