vendor/flate2-1.0.23/src/gz/mod.rs - toolchain/rustc - Git at Google

 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");
             }
         }
     }
 }
	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");
	}
	}
	}
	}