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Diffstat (limited to 'third_party/rust/flate2/src/gz/mod.rs')
| -rw-r--r-- | third_party/rust/flate2/src/gz/mod.rs | 385 |
1 files changed, 385 insertions, 0 deletions
diff --git a/third_party/rust/flate2/src/gz/mod.rs b/third_party/rust/flate2/src/gz/mod.rs new file mode 100644 index 0000000000..505450e3e9 --- /dev/null +++ b/third_party/rust/flate2/src/gz/mod.rs @@ -0,0 +1,385 @@ +use std::ffi::CString; +use std::io::prelude::*; +use std::time; + +use crate::bufreader::BufReader; +use crate::Compression; + +pub static FHCRC: u8 = 1 << 1; +pub static FEXTRA: u8 = 1 << 2; +pub static FNAME: u8 = 1 << 3; +pub static FCOMMENT: u8 = 1 << 4; + +pub mod bufread; +pub mod read; +pub mod write; + +/// A structure representing the header of a gzip stream. +/// +/// The header can contain metadata about the file that was compressed, if +/// present. +#[derive(PartialEq, Clone, Debug, Default)] +pub struct GzHeader { + extra: Option<Vec<u8>>, + filename: Option<Vec<u8>>, + comment: Option<Vec<u8>>, + operating_system: u8, + mtime: u32, +} + +impl GzHeader { + /// Returns the `filename` field of this gzip stream's header, if present. + pub fn filename(&self) -> Option<&[u8]> { + self.filename.as_ref().map(|s| &s[..]) + } + + /// Returns the `extra` field of this gzip stream's header, if present. + pub fn extra(&self) -> Option<&[u8]> { + self.extra.as_ref().map(|s| &s[..]) + } + + /// Returns the `comment` field of this gzip stream's header, if present. + pub fn comment(&self) -> Option<&[u8]> { + self.comment.as_ref().map(|s| &s[..]) + } + + /// Returns the `operating_system` field of this gzip stream's header. + /// + /// There are predefined values for various operating systems. + /// 255 means that the value is unknown. + pub fn operating_system(&self) -> u8 { + self.operating_system + } + + /// This gives the most recent modification time of the original file being compressed. + /// + /// The time is in Unix format, i.e., seconds since 00:00:00 GMT, Jan. 1, 1970. + /// (Note that this may cause problems for MS-DOS and other systems that use local + /// rather than Universal time.) If the compressed data did not come from a file, + /// `mtime` is set to the time at which compression started. + /// `mtime` = 0 means no time stamp is available. + /// + /// The usage of `mtime` is discouraged because of Year 2038 problem. + pub fn mtime(&self) -> u32 { + self.mtime + } + + /// Returns the most recent modification time represented by a date-time type. + /// Returns `None` if the value of the underlying counter is 0, + /// indicating no time stamp is available. + /// + /// + /// The time is measured as seconds since 00:00:00 GMT, Jan. 1 1970. + /// See [`mtime`](#method.mtime) for more detail. + pub fn mtime_as_datetime(&self) -> Option<time::SystemTime> { + if self.mtime == 0 { + None + } else { + let duration = time::Duration::new(u64::from(self.mtime), 0); + let datetime = time::UNIX_EPOCH + duration; + Some(datetime) + } + } +} + +/// A builder structure to create a new gzip Encoder. +/// +/// This structure controls header configuration options such as the filename. +/// +/// # Examples +/// +/// ``` +/// use std::io::prelude::*; +/// # use std::io; +/// use std::fs::File; +/// use flate2::GzBuilder; +/// use flate2::Compression; +/// +/// // GzBuilder opens a file and writes a sample string using GzBuilder pattern +/// +/// # fn sample_builder() -> Result<(), io::Error> { +/// let f = File::create("examples/hello_world.gz")?; +/// let mut gz = GzBuilder::new() +/// .filename("hello_world.txt") +/// .comment("test file, please delete") +/// .write(f, Compression::default()); +/// gz.write_all(b"hello world")?; +/// gz.finish()?; +/// # Ok(()) +/// # } +/// ``` +#[derive(Debug)] +pub struct GzBuilder { + extra: Option<Vec<u8>>, + filename: Option<CString>, + comment: Option<CString>, + operating_system: Option<u8>, + mtime: u32, +} + +impl Default for GzBuilder { + fn default() -> Self { + Self::new() + } +} + +impl GzBuilder { + /// Create a new blank builder with no header by default. + pub fn new() -> GzBuilder { + GzBuilder { + extra: None, + filename: None, + comment: None, + operating_system: None, + mtime: 0, + } + } + + /// Configure the `mtime` field in the gzip header. + pub fn mtime(mut self, mtime: u32) -> GzBuilder { + self.mtime = mtime; + self + } + + /// Configure the `operating_system` field in the gzip header. + pub fn operating_system(mut self, os: u8) -> GzBuilder { + self.operating_system = Some(os); + self + } + + /// Configure the `extra` field in the gzip header. + pub fn extra<T: Into<Vec<u8>>>(mut self, extra: T) -> GzBuilder { + self.extra = Some(extra.into()); + self + } + + /// Configure the `filename` field in the gzip header. + /// + /// # Panics + /// + /// Panics if the `filename` slice contains a zero. + pub fn filename<T: Into<Vec<u8>>>(mut self, filename: T) -> GzBuilder { + self.filename = Some(CString::new(filename.into()).unwrap()); + self + } + + /// Configure the `comment` field in the gzip header. + /// + /// # Panics + /// + /// Panics if the `comment` slice contains a zero. + pub fn comment<T: Into<Vec<u8>>>(mut self, comment: T) -> GzBuilder { + self.comment = Some(CString::new(comment.into()).unwrap()); + self + } + + /// Consume this builder, creating a writer encoder in the process. + /// + /// The data written to the returned encoder will be compressed and then + /// written out to the supplied parameter `w`. + pub fn write<W: Write>(self, w: W, lvl: Compression) -> write::GzEncoder<W> { + write::gz_encoder(self.into_header(lvl), w, lvl) + } + + /// Consume this builder, creating a reader encoder in the process. + /// + /// Data read from the returned encoder will be the compressed version of + /// the data read from the given reader. + pub fn read<R: Read>(self, r: R, lvl: Compression) -> read::GzEncoder<R> { + read::gz_encoder(self.buf_read(BufReader::new(r), lvl)) + } + + /// Consume this builder, creating a reader encoder in the process. + /// + /// Data read from the returned encoder will be the compressed version of + /// the data read from the given reader. + pub fn buf_read<R>(self, r: R, lvl: Compression) -> bufread::GzEncoder<R> + where + R: BufRead, + { + bufread::gz_encoder(self.into_header(lvl), r, lvl) + } + + fn into_header(self, lvl: Compression) -> Vec<u8> { + let GzBuilder { + extra, + filename, + comment, + operating_system, + mtime, + } = self; + let mut flg = 0; + let mut header = vec![0u8; 10]; + if let Some(v) = extra { + flg |= FEXTRA; + header.push((v.len() >> 0) as u8); + header.push((v.len() >> 8) as u8); + header.extend(v); + } + if let Some(filename) = filename { + flg |= FNAME; + header.extend(filename.as_bytes_with_nul().iter().map(|x| *x)); + } + if let Some(comment) = comment { + flg |= FCOMMENT; + header.extend(comment.as_bytes_with_nul().iter().map(|x| *x)); + } + header[0] = 0x1f; + header[1] = 0x8b; + header[2] = 8; + header[3] = flg; + header[4] = (mtime >> 0) as u8; + header[5] = (mtime >> 8) as u8; + header[6] = (mtime >> 16) as u8; + header[7] = (mtime >> 24) as u8; + header[8] = if lvl.0 >= Compression::best().0 { + 2 + } else if lvl.0 <= Compression::fast().0 { + 4 + } else { + 0 + }; + + // Typically this byte indicates what OS the gz stream was created on, + // but in an effort to have cross-platform reproducible streams just + // default this value to 255. I'm not sure that if we "correctly" set + // this it'd do anything anyway... + header[9] = operating_system.unwrap_or(255); + header + } +} + +#[cfg(test)] +mod tests { + use std::io::prelude::*; + + use super::{read, write, GzBuilder}; + use crate::Compression; + use rand::{thread_rng, Rng}; + + #[test] + fn roundtrip() { + let mut e = write::GzEncoder::new(Vec::new(), Compression::default()); + e.write_all(b"foo bar baz").unwrap(); + let inner = e.finish().unwrap(); + let mut d = read::GzDecoder::new(&inner[..]); + let mut s = String::new(); + d.read_to_string(&mut s).unwrap(); + assert_eq!(s, "foo bar baz"); + } + + #[test] + fn roundtrip_zero() { + let e = write::GzEncoder::new(Vec::new(), Compression::default()); + let inner = e.finish().unwrap(); + let mut d = read::GzDecoder::new(&inner[..]); + let mut s = String::new(); + d.read_to_string(&mut s).unwrap(); + assert_eq!(s, ""); + } + + #[test] + fn roundtrip_big() { + let mut real = Vec::new(); + let mut w = write::GzEncoder::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::GzDecoder::new(&result[..]); + let mut v = Vec::new(); + r.read_to_end(&mut v).unwrap(); + assert!(v == real); + } + + #[test] + fn roundtrip_big2() { + let v = crate::random_bytes().take(1024 * 1024).collect::<Vec<_>>(); + let mut r = read::GzDecoder::new(read::GzEncoder::new(&v[..], Compression::default())); + let mut res = Vec::new(); + r.read_to_end(&mut res).unwrap(); + assert!(res == v); + } + + #[test] + fn fields() { + let r = vec![0, 2, 4, 6]; + let e = GzBuilder::new() + .filename("foo.rs") + .comment("bar") + .extra(vec![0, 1, 2, 3]) + .read(&r[..], Compression::default()); + let mut d = read::GzDecoder::new(e); + assert_eq!(d.header().unwrap().filename(), Some(&b"foo.rs"[..])); + assert_eq!(d.header().unwrap().comment(), Some(&b"bar"[..])); + assert_eq!(d.header().unwrap().extra(), Some(&b"\x00\x01\x02\x03"[..])); + let mut res = Vec::new(); + d.read_to_end(&mut res).unwrap(); + assert_eq!(res, vec![0, 2, 4, 6]); + } + + #[test] + fn keep_reading_after_end() { + let mut e = write::GzEncoder::new(Vec::new(), Compression::default()); + e.write_all(b"foo bar baz").unwrap(); + let inner = e.finish().unwrap(); + let mut d = read::GzDecoder::new(&inner[..]); + let mut s = String::new(); + d.read_to_string(&mut s).unwrap(); + assert_eq!(s, "foo bar baz"); + d.read_to_string(&mut s).unwrap(); + assert_eq!(s, "foo bar baz"); + } + + #[test] + fn qc_reader() { + ::quickcheck::quickcheck(test as fn(_) -> _); + + fn test(v: Vec<u8>) -> bool { + let r = read::GzEncoder::new(&v[..], Compression::default()); + let mut r = read::GzDecoder::new(r); + let mut v2 = Vec::new(); + r.read_to_end(&mut v2).unwrap(); + v == v2 + } + } + + #[test] + fn flush_after_write() { + let mut f = write::GzEncoder::new(Vec::new(), Compression::default()); + write!(f, "Hello world").unwrap(); + f.flush().unwrap(); + } + + use crate::gz::bufread::tests::BlockingCursor; + #[test] + // test function read_and_forget of Buffer + fn blocked_partial_header_read() { + // this is a reader which receives data afterwards + let mut r = BlockingCursor::new(); + let data = vec![1, 2, 3]; + + match r.write_all(&data) { + Ok(()) => {} + _ => { + panic!("Unexpected result for write_all"); + } + } + r.set_position(0); + + // this is unused except for the buffering + let mut decoder = read::GzDecoder::new(r); + let mut out = Vec::with_capacity(7); + match decoder.read(&mut out) { + Err(e) => { + assert_eq!(e.kind(), std::io::ErrorKind::WouldBlock); + } + _ => { + panic!("Unexpected result for decoder.read"); + } + } + } +} |