diff options
Diffstat (limited to 'vendor/flate2/src/gz')
-rw-r--r-- | vendor/flate2/src/gz/bufread.rs | 483 | ||||
-rw-r--r-- | vendor/flate2/src/gz/mod.rs | 644 | ||||
-rw-r--r-- | vendor/flate2/src/gz/read.rs | 378 | ||||
-rw-r--r-- | vendor/flate2/src/gz/write.rs | 641 |
4 files changed, 2146 insertions, 0 deletions
diff --git a/vendor/flate2/src/gz/bufread.rs b/vendor/flate2/src/gz/bufread.rs new file mode 100644 index 0000000..679b4a7 --- /dev/null +++ b/vendor/flate2/src/gz/bufread.rs @@ -0,0 +1,483 @@ +use std::cmp; +use std::io; +use std::io::prelude::*; +use std::mem; + +use super::{corrupt, read_into, GzBuilder, GzHeader, GzHeaderParser}; +use crate::crc::CrcReader; +use crate::deflate; +use crate::Compression; + +fn copy(into: &mut [u8], from: &[u8], pos: &mut usize) -> usize { + let min = cmp::min(into.len(), from.len() - *pos); + for (slot, val) in into.iter_mut().zip(from[*pos..*pos + min].iter()) { + *slot = *val; + } + *pos += min; + min +} + +/// A gzip streaming encoder +/// +/// This structure implements a [`Read`] interface. When read from, it reads +/// uncompressed data from the underlying [`BufRead`] and provides the compressed data. +/// +/// [`Read`]: https://doc.rust-lang.org/std/io/trait.Read.html +/// [`BufRead`]: https://doc.rust-lang.org/std/io/trait.BufRead.html +/// +/// # Examples +/// +/// ``` +/// use std::io::prelude::*; +/// use std::io; +/// use flate2::Compression; +/// use flate2::bufread::GzEncoder; +/// use std::fs::File; +/// use std::io::BufReader; +/// +/// // Opens sample file, compresses the contents and returns a Vector or error +/// // File wrapped in a BufReader implements BufRead +/// +/// fn open_hello_world() -> io::Result<Vec<u8>> { +/// let f = File::open("examples/hello_world.txt")?; +/// let b = BufReader::new(f); +/// let mut gz = GzEncoder::new(b, Compression::fast()); +/// let mut buffer = Vec::new(); +/// gz.read_to_end(&mut buffer)?; +/// Ok(buffer) +/// } +/// ``` +#[derive(Debug)] +pub struct GzEncoder<R> { + inner: deflate::bufread::DeflateEncoder<CrcReader<R>>, + header: Vec<u8>, + pos: usize, + eof: bool, +} + +pub fn gz_encoder<R: BufRead>(header: Vec<u8>, r: R, lvl: Compression) -> GzEncoder<R> { + let crc = CrcReader::new(r); + GzEncoder { + inner: deflate::bufread::DeflateEncoder::new(crc, lvl), + header, + pos: 0, + eof: false, + } +} + +impl<R: BufRead> GzEncoder<R> { + /// Creates a new encoder which will use the given compression level. + /// + /// The encoder is not configured specially for the emitted header. For + /// header configuration, see the `GzBuilder` type. + /// + /// The data read from the stream `r` will be compressed and available + /// through the returned reader. + pub fn new(r: R, level: Compression) -> GzEncoder<R> { + GzBuilder::new().buf_read(r, level) + } + + fn read_footer(&mut self, into: &mut [u8]) -> io::Result<usize> { + if self.pos == 8 { + return Ok(0); + } + let crc = self.inner.get_ref().crc(); + let ref arr = [ + (crc.sum() >> 0) as u8, + (crc.sum() >> 8) as u8, + (crc.sum() >> 16) as u8, + (crc.sum() >> 24) as u8, + (crc.amount() >> 0) as u8, + (crc.amount() >> 8) as u8, + (crc.amount() >> 16) as u8, + (crc.amount() >> 24) as u8, + ]; + Ok(copy(into, arr, &mut self.pos)) + } +} + +impl<R> GzEncoder<R> { + /// Acquires a reference to the underlying reader. + pub fn get_ref(&self) -> &R { + self.inner.get_ref().get_ref() + } + + /// Acquires a mutable reference to the underlying reader. + /// + /// Note that mutation of the reader 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() + } + + /// Returns the underlying stream, consuming this encoder + pub fn into_inner(self) -> R { + self.inner.into_inner().into_inner() + } +} + +#[inline] +fn finish(buf: &[u8; 8]) -> (u32, u32) { + let crc = ((buf[0] as u32) << 0) + | ((buf[1] as u32) << 8) + | ((buf[2] as u32) << 16) + | ((buf[3] as u32) << 24); + let amt = ((buf[4] as u32) << 0) + | ((buf[5] as u32) << 8) + | ((buf[6] as u32) << 16) + | ((buf[7] as u32) << 24); + (crc, amt) +} + +impl<R: BufRead> Read for GzEncoder<R> { + fn read(&mut self, mut into: &mut [u8]) -> io::Result<usize> { + let mut amt = 0; + if self.eof { + return self.read_footer(into); + } else if self.pos < self.header.len() { + amt += copy(into, &self.header, &mut self.pos); + if amt == into.len() { + return Ok(amt); + } + let tmp = into; + into = &mut tmp[amt..]; + } + match self.inner.read(into)? { + 0 => { + self.eof = true; + self.pos = 0; + self.read_footer(into) + } + n => Ok(amt + n), + } + } +} + +impl<R: BufRead + Write> Write for GzEncoder<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 decoder for a single member of a [gzip file]. +/// +/// This structure implements a [`Read`] interface. When read from, it reads +/// compressed data from the underlying [`BufRead`] and provides the uncompressed data. +/// +/// After reading a single member of the gzip data this reader will return +/// Ok(0) even if there are more bytes available in the underlying reader. +/// If you need the following bytes, call `into_inner()` after Ok(0) to +/// recover the underlying reader. +/// +/// To handle gzip files that may have multiple members, see [`MultiGzDecoder`] +/// or read more +/// [in the introduction](../index.html#about-multi-member-gzip-files). +/// +/// [gzip file]: https://www.rfc-editor.org/rfc/rfc1952#page-5 +/// [`Read`]: https://doc.rust-lang.org/std/io/trait.Read.html +/// [`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::GzEncoder; +/// use flate2::bufread::GzDecoder; +/// +/// # fn main() { +/// # let mut e = GzEncoder::new(Vec::new(), Compression::default()); +/// # e.write_all(b"Hello World").unwrap(); +/// # let bytes = e.finish().unwrap(); +/// # println!("{}", decode_reader(bytes).unwrap()); +/// # } +/// # +/// // Uncompresses a Gz Encoded vector of bytes and returns a string or error +/// // Here &[u8] implements BufRead +/// +/// fn decode_reader(bytes: Vec<u8>) -> io::Result<String> { +/// let mut gz = GzDecoder::new(&bytes[..]); +/// let mut s = String::new(); +/// gz.read_to_string(&mut s)?; +/// Ok(s) +/// } +/// ``` +#[derive(Debug)] +pub struct GzDecoder<R> { + state: GzState, + reader: CrcReader<deflate::bufread::DeflateDecoder<R>>, + multi: bool, +} + +#[derive(Debug)] +enum GzState { + Header(GzHeaderParser), + Body(GzHeader), + Finished(GzHeader, usize, [u8; 8]), + Err(io::Error), + End(Option<GzHeader>), +} + +impl<R: BufRead> GzDecoder<R> { + /// Creates a new decoder from the given reader, immediately parsing the + /// gzip header. + pub fn new(mut r: R) -> GzDecoder<R> { + let mut header_parser = GzHeaderParser::new(); + + let state = match header_parser.parse(&mut r) { + Ok(_) => GzState::Body(GzHeader::from(header_parser)), + Err(ref err) if io::ErrorKind::WouldBlock == err.kind() => { + GzState::Header(header_parser) + } + Err(err) => GzState::Err(err), + }; + + GzDecoder { + state, + reader: CrcReader::new(deflate::bufread::DeflateDecoder::new(r)), + multi: false, + } + } + + fn multi(mut self, flag: bool) -> GzDecoder<R> { + self.multi = flag; + self + } +} + +impl<R> GzDecoder<R> { + /// Returns the header associated with this stream, if it was valid + pub fn header(&self) -> Option<&GzHeader> { + match &self.state { + GzState::Body(header) | GzState::Finished(header, _, _) => Some(header), + GzState::End(header) => header.as_ref(), + _ => None, + } + } + + /// Acquires a reference to the underlying reader. + pub fn get_ref(&self) -> &R { + self.reader.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.reader.get_mut().get_mut() + } + + /// Consumes this decoder, returning the underlying reader. + pub fn into_inner(self) -> R { + self.reader.into_inner().into_inner() + } +} + +impl<R: BufRead> Read for GzDecoder<R> { + fn read(&mut self, into: &mut [u8]) -> io::Result<usize> { + loop { + match &mut self.state { + GzState::Header(parser) => { + parser.parse(self.reader.get_mut().get_mut())?; + self.state = GzState::Body(GzHeader::from(mem::take(parser))); + } + GzState::Body(header) => { + if into.is_empty() { + return Ok(0); + } + match self.reader.read(into)? { + 0 => { + self.state = GzState::Finished(mem::take(header), 0, [0; 8]); + } + n => { + return Ok(n); + } + } + } + GzState::Finished(header, pos, buf) => { + if *pos < buf.len() { + *pos += read_into(self.reader.get_mut().get_mut(), &mut buf[*pos..])?; + } else { + let (crc, amt) = finish(&buf); + + if crc != self.reader.crc().sum() || amt != self.reader.crc().amount() { + self.state = GzState::End(Some(mem::take(header))); + return Err(corrupt()); + } else if self.multi { + let is_eof = self + .reader + .get_mut() + .get_mut() + .fill_buf() + .map(|buf| buf.is_empty())?; + + if is_eof { + self.state = GzState::End(Some(mem::take(header))); + } else { + self.reader.reset(); + self.reader.get_mut().reset_data(); + self.state = GzState::Header(GzHeaderParser::new()) + } + } else { + self.state = GzState::End(Some(mem::take(header))); + } + } + } + GzState::Err(err) => { + let result = Err(mem::replace(err, io::ErrorKind::Other.into())); + self.state = GzState::End(None); + return result; + } + GzState::End(_) => return Ok(0), + } + } + } +} + +impl<R: BufRead + Write> Write for GzDecoder<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 gzip streaming decoder that decodes a [gzip file] that may have multiple members. +/// +/// This structure implements a [`Read`] interface. When read from, it reads +/// compressed data from the underlying [`BufRead`] and provides the uncompressed data. +/// +/// A gzip file consists of a series of *members* concatenated one after another. +/// MultiGzDecoder decodes all members from the data and only returns Ok(0) when the +/// underlying reader does. For a file, this reads to the end of the file. +/// +/// To handle members seperately, see [GzDecoder] or read more +/// [in the introduction](../index.html#about-multi-member-gzip-files). +/// +/// [gzip file]: https://www.rfc-editor.org/rfc/rfc1952#page-5 +/// [`Read`]: https://doc.rust-lang.org/std/io/trait.Read.html +/// [`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::GzEncoder; +/// use flate2::bufread::MultiGzDecoder; +/// +/// # fn main() { +/// # let mut e = GzEncoder::new(Vec::new(), Compression::default()); +/// # e.write_all(b"Hello World").unwrap(); +/// # let bytes = e.finish().unwrap(); +/// # println!("{}", decode_reader(bytes).unwrap()); +/// # } +/// # +/// // Uncompresses a Gz Encoded vector of bytes and returns a string or error +/// // Here &[u8] implements BufRead +/// +/// fn decode_reader(bytes: Vec<u8>) -> io::Result<String> { +/// let mut gz = MultiGzDecoder::new(&bytes[..]); +/// let mut s = String::new(); +/// gz.read_to_string(&mut s)?; +/// Ok(s) +/// } +/// ``` +#[derive(Debug)] +pub struct MultiGzDecoder<R>(GzDecoder<R>); + +impl<R: BufRead> MultiGzDecoder<R> { + /// Creates a new decoder from the given reader, immediately parsing the + /// (first) gzip header. If the gzip stream contains multiple members all will + /// be decoded. + pub fn new(r: R) -> MultiGzDecoder<R> { + MultiGzDecoder(GzDecoder::new(r).multi(true)) + } +} + +impl<R> MultiGzDecoder<R> { + /// Returns the current header associated with this stream, if it's valid + pub fn header(&self) -> Option<&GzHeader> { + self.0.header() + } + + /// Acquires a reference to the underlying reader. + pub fn get_ref(&self) -> &R { + self.0.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.0.get_mut() + } + + /// Consumes this decoder, returning the underlying reader. + pub fn into_inner(self) -> R { + self.0.into_inner() + } +} + +impl<R: BufRead> Read for MultiGzDecoder<R> { + fn read(&mut self, into: &mut [u8]) -> io::Result<usize> { + self.0.read(into) + } +} + +#[cfg(test)] +mod test { + use crate::bufread::GzDecoder; + use crate::gz::write; + use crate::Compression; + use std::io::{Read, Write}; + + // GzDecoder consumes one gzip member and then returns 0 for subsequent reads, allowing any + // additional data to be consumed by the caller. + #[test] + fn decode_extra_data() { + let expected = "Hello World"; + + let compressed = { + let mut e = write::GzEncoder::new(Vec::new(), Compression::default()); + e.write(expected.as_ref()).unwrap(); + let mut b = e.finish().unwrap(); + b.push(b'x'); + b + }; + + let mut output = Vec::new(); + let mut decoder = GzDecoder::new(compressed.as_slice()); + let decoded_bytes = decoder.read_to_end(&mut output).unwrap(); + assert_eq!(decoded_bytes, output.len()); + let actual = std::str::from_utf8(&output).expect("String parsing error"); + assert_eq!( + actual, expected, + "after decompression we obtain the original input" + ); + + output.clear(); + assert_eq!( + decoder.read(&mut output).unwrap(), + 0, + "subsequent read of decoder returns 0, but inner reader can return additional data" + ); + let mut reader = decoder.into_inner(); + assert_eq!( + reader.read_to_end(&mut output).unwrap(), + 1, + "extra data is accessible in underlying buf-read" + ); + assert_eq!(output, b"x"); + } +} diff --git a/vendor/flate2/src/gz/mod.rs b/vendor/flate2/src/gz/mod.rs new file mode 100644 index 0000000..31a6961 --- /dev/null +++ b/vendor/flate2/src/gz/mod.rs @@ -0,0 +1,644 @@ +use std::ffi::CString; +use std::io::{BufRead, Error, ErrorKind, Read, Result, Write}; +use std::time; + +use crate::bufreader::BufReader; +use crate::{Compression, Crc}; + +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 static FRESERVED: u8 = 1 << 5 | 1 << 6 | 1 << 7; + +pub mod bufread; +pub mod read; +pub mod write; + +// The maximum length of the header filename and comment fields. More than +// enough for these fields in reasonable use, but prevents possible attacks. +const MAX_HEADER_BUF: usize = 65535; + +/// 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) + } + } +} + +#[derive(Debug)] +pub enum GzHeaderState { + Start(u8, [u8; 10]), + Xlen(Option<Box<Crc>>, u8, [u8; 2]), + Extra(Option<Box<Crc>>, u16), + Filename(Option<Box<Crc>>), + Comment(Option<Box<Crc>>), + Crc(Option<Box<Crc>>, u8, [u8; 2]), + Complete, +} + +impl Default for GzHeaderState { + fn default() -> Self { + Self::Complete + } +} + +#[derive(Debug, Default)] +pub struct GzHeaderParser { + state: GzHeaderState, + flags: u8, + header: GzHeader, +} + +impl GzHeaderParser { + fn new() -> Self { + GzHeaderParser { + state: GzHeaderState::Start(0, [0; 10]), + flags: 0, + header: GzHeader::default(), + } + } + + fn parse<'a, R: Read>(&mut self, r: &'a mut R) -> Result<()> { + loop { + match &mut self.state { + GzHeaderState::Start(count, buffer) => { + while (*count as usize) < buffer.len() { + *count += read_into(r, &mut buffer[*count as usize..])? as u8; + } + // Gzip identification bytes + if buffer[0] != 0x1f || buffer[1] != 0x8b { + return Err(bad_header()); + } + // Gzip compression method (8 = deflate) + if buffer[2] != 8 { + return Err(bad_header()); + } + self.flags = buffer[3]; + // RFC1952: "must give an error indication if any reserved bit is non-zero" + if self.flags & FRESERVED != 0 { + return Err(bad_header()); + } + self.header.mtime = ((buffer[4] as u32) << 0) + | ((buffer[5] as u32) << 8) + | ((buffer[6] as u32) << 16) + | ((buffer[7] as u32) << 24); + let _xfl = buffer[8]; + self.header.operating_system = buffer[9]; + let crc = if self.flags & FHCRC != 0 { + let mut crc = Box::new(Crc::new()); + crc.update(buffer); + Some(crc) + } else { + None + }; + self.state = GzHeaderState::Xlen(crc, 0, [0; 2]); + } + GzHeaderState::Xlen(crc, count, buffer) => { + if self.flags & FEXTRA != 0 { + while (*count as usize) < buffer.len() { + *count += read_into(r, &mut buffer[*count as usize..])? as u8; + } + if let Some(crc) = crc { + crc.update(buffer); + } + let xlen = parse_le_u16(&buffer); + self.header.extra = Some(vec![0; xlen as usize]); + self.state = GzHeaderState::Extra(crc.take(), 0); + } else { + self.state = GzHeaderState::Filename(crc.take()); + } + } + GzHeaderState::Extra(crc, count) => { + debug_assert!(self.header.extra.is_some()); + let extra = self.header.extra.as_mut().unwrap(); + while (*count as usize) < extra.len() { + *count += read_into(r, &mut extra[*count as usize..])? as u16; + } + if let Some(crc) = crc { + crc.update(extra); + } + self.state = GzHeaderState::Filename(crc.take()); + } + GzHeaderState::Filename(crc) => { + if self.flags & FNAME != 0 { + let filename = self.header.filename.get_or_insert_with(Vec::new); + read_to_nul(r, filename)?; + if let Some(crc) = crc { + crc.update(filename); + crc.update(b"\0"); + } + } + self.state = GzHeaderState::Comment(crc.take()); + } + GzHeaderState::Comment(crc) => { + if self.flags & FCOMMENT != 0 { + let comment = self.header.comment.get_or_insert_with(Vec::new); + read_to_nul(r, comment)?; + if let Some(crc) = crc { + crc.update(comment); + crc.update(b"\0"); + } + } + self.state = GzHeaderState::Crc(crc.take(), 0, [0; 2]); + } + GzHeaderState::Crc(crc, count, buffer) => { + if let Some(crc) = crc { + debug_assert!(self.flags & FHCRC != 0); + while (*count as usize) < buffer.len() { + *count += read_into(r, &mut buffer[*count as usize..])? as u8; + } + let stored_crc = parse_le_u16(&buffer); + let calced_crc = crc.sum() as u16; + if stored_crc != calced_crc { + return Err(corrupt()); + } + } + self.state = GzHeaderState::Complete; + } + GzHeaderState::Complete => { + return Ok(()); + } + } + } + } + + fn header(&self) -> Option<&GzHeader> { + match self.state { + GzHeaderState::Complete => Some(&self.header), + _ => None, + } + } +} + +impl From<GzHeaderParser> for GzHeader { + fn from(parser: GzHeaderParser) -> Self { + debug_assert!(matches!(parser.state, GzHeaderState::Complete)); + parser.header + } +} + +// Attempt to fill the `buffer` from `r`. Return the number of bytes read. +// Return an error if EOF is read before the buffer is full. This differs +// from `read` in that Ok(0) means that more data may be available. +fn read_into<R: Read>(r: &mut R, buffer: &mut [u8]) -> Result<usize> { + debug_assert!(!buffer.is_empty()); + match r.read(buffer) { + Ok(0) => Err(ErrorKind::UnexpectedEof.into()), + Ok(n) => Ok(n), + Err(ref e) if e.kind() == ErrorKind::Interrupted => Ok(0), + Err(e) => Err(e), + } +} + +// Read `r` up to the first nul byte, pushing non-nul bytes to `buffer`. +fn read_to_nul<R: Read>(r: &mut R, buffer: &mut Vec<u8>) -> Result<()> { + let mut bytes = r.bytes(); + loop { + match bytes.next().transpose()? { + Some(byte) if byte == 0 => { + return Ok(()); + } + Some(_) if buffer.len() == MAX_HEADER_BUF => { + return Err(Error::new( + ErrorKind::InvalidInput, + "gzip header field too long", + )); + } + Some(byte) => { + buffer.push(byte); + } + None => { + return Err(ErrorKind::UnexpectedEof.into()); + } + } + } +} + +fn parse_le_u16(buffer: &[u8; 2]) -> u16 { + (buffer[0] as u16) | ((buffer[1] as u16) << 8) +} + +fn bad_header() -> Error { + Error::new(ErrorKind::InvalidInput, "invalid gzip header") +} + +fn corrupt() -> Error { + Error::new( + ErrorKind::InvalidInput, + "corrupt gzip stream does not have a matching checksum", + ) +} + +/// 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().copied()); + } + if let Some(comment) = comment { + flg |= FCOMMENT; + header.extend(comment.as_bytes_with_nul().iter().copied()); + } + 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, GzHeaderParser}; + use crate::{Compression, GzHeader}; + 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().copied()); + 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_eq!(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_eq!(res, v); + } + + // A Rust implementation of CRC that closely matches the C code in RFC1952. + // Only use this to create CRCs for tests. + struct Rfc1952Crc { + /* Table of CRCs of all 8-bit messages. */ + crc_table: [u32; 256], + } + + impl Rfc1952Crc { + fn new() -> Self { + let mut crc = Rfc1952Crc { + crc_table: [0; 256], + }; + /* Make the table for a fast CRC. */ + for n in 0usize..256 { + let mut c = n as u32; + for _k in 0..8 { + if c & 1 != 0 { + c = 0xedb88320 ^ (c >> 1); + } else { + c = c >> 1; + } + } + crc.crc_table[n] = c; + } + crc + } + + /* + Update a running crc with the bytes buf and return + the updated crc. The crc should be initialized to zero. Pre- and + post-conditioning (one's complement) is performed within this + function so it shouldn't be done by the caller. + */ + fn update_crc(&self, crc: u32, buf: &[u8]) -> u32 { + let mut c = crc ^ 0xffffffff; + + for b in buf { + c = self.crc_table[(c as u8 ^ *b) as usize] ^ (c >> 8); + } + c ^ 0xffffffff + } + + /* Return the CRC of the bytes buf. */ + fn crc(&self, buf: &[u8]) -> u32 { + self.update_crc(0, buf) + } + } + + #[test] + fn roundtrip_header() { + let mut header = GzBuilder::new() + .mtime(1234) + .operating_system(57) + .filename("filename") + .comment("comment") + .into_header(Compression::fast()); + + // Add a CRC to the header + header[3] = header[3] ^ super::FHCRC; + let rfc1952_crc = Rfc1952Crc::new(); + let crc32 = rfc1952_crc.crc(&header); + let crc16 = crc32 as u16; + header.extend(&crc16.to_le_bytes()); + + let mut parser = GzHeaderParser::new(); + parser.parse(&mut header.as_slice()).unwrap(); + let actual = parser.header().unwrap(); + assert_eq!( + actual, + &GzHeader { + extra: None, + filename: Some("filename".as_bytes().to_vec()), + comment: Some("comment".as_bytes().to_vec()), + operating_system: 57, + mtime: 1234 + } + ) + } + + #[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(); + } +} diff --git a/vendor/flate2/src/gz/read.rs b/vendor/flate2/src/gz/read.rs new file mode 100644 index 0000000..9dbadbd --- /dev/null +++ b/vendor/flate2/src/gz/read.rs @@ -0,0 +1,378 @@ +use std::io; +use std::io::prelude::*; + +use super::bufread; +use super::{GzBuilder, GzHeader}; +use crate::bufreader::BufReader; +use crate::Compression; + +/// A gzip streaming encoder +/// +/// 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 std::io; +/// use flate2::Compression; +/// use flate2::read::GzEncoder; +/// +/// // Return a vector containing the GZ compressed version of hello world +/// +/// fn gzencode_hello_world() -> io::Result<Vec<u8>> { +/// let mut ret_vec = Vec::new(); +/// let bytestring = b"hello world"; +/// let mut gz = GzEncoder::new(&bytestring[..], Compression::fast()); +/// gz.read_to_end(&mut ret_vec)?; +/// Ok(ret_vec) +/// } +/// ``` +#[derive(Debug)] +pub struct GzEncoder<R> { + inner: bufread::GzEncoder<BufReader<R>>, +} + +pub fn gz_encoder<R: Read>(inner: bufread::GzEncoder<BufReader<R>>) -> GzEncoder<R> { + GzEncoder { inner } +} + +impl<R: Read> GzEncoder<R> { + /// Creates a new encoder which will use the given compression level. + /// + /// The encoder is not configured specially for the emitted header. For + /// header configuration, see the `GzBuilder` type. + /// + /// The data read from the stream `r` will be compressed and available + /// through the returned reader. + pub fn new(r: R, level: Compression) -> GzEncoder<R> { + GzBuilder::new().read(r, level) + } +} + +impl<R> GzEncoder<R> { + /// Acquires a reference to the underlying reader. + pub fn get_ref(&self) -> &R { + self.inner.get_ref().get_ref() + } + + /// Acquires a mutable reference to the underlying reader. + /// + /// Note that mutation of the reader 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() + } + + /// Returns the underlying stream, consuming this encoder + pub fn into_inner(self) -> R { + self.inner.into_inner().into_inner() + } +} + +impl<R: Read> Read for GzEncoder<R> { + fn read(&mut self, into: &mut [u8]) -> io::Result<usize> { + self.inner.read(into) + } +} + +impl<R: Read + Write> Write for GzEncoder<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 decoder for a single member of a [gzip file]. +/// +/// This structure implements a [`Read`] interface. When read from, it reads +/// compressed data from the underlying [`Read`] and provides the uncompressed data. +/// +/// After reading a single member of the gzip data this reader will return +/// Ok(0) even if there are more bytes available in the underlying reader. +/// `GzDecoder` may have read additional bytes past the end of the gzip data. +/// If you need the following bytes, wrap the `Reader` in a `std::io::BufReader` +/// and use `bufread::GzDecoder` instead. +/// +/// To handle gzip files that may have multiple members, see [`MultiGzDecoder`] +/// or read more +/// [in the introduction](../index.html#about-multi-member-gzip-files). +/// +/// [gzip file]: https://www.rfc-editor.org/rfc/rfc1952#page-5 +/// +/// # Examples +/// +/// ``` +/// use std::io::prelude::*; +/// use std::io; +/// # use flate2::Compression; +/// # use flate2::write::GzEncoder; +/// use flate2::read::GzDecoder; +/// +/// # fn main() { +/// # let mut e = GzEncoder::new(Vec::new(), Compression::default()); +/// # e.write_all(b"Hello World").unwrap(); +/// # let bytes = e.finish().unwrap(); +/// # println!("{}", decode_reader(bytes).unwrap()); +/// # } +/// # +/// // Uncompresses a Gz 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 gz = GzDecoder::new(&bytes[..]); +/// let mut s = String::new(); +/// gz.read_to_string(&mut s)?; +/// Ok(s) +/// } +/// ``` +#[derive(Debug)] +pub struct GzDecoder<R> { + inner: bufread::GzDecoder<BufReader<R>>, +} + +impl<R: Read> GzDecoder<R> { + /// Creates a new decoder from the given reader, immediately parsing the + /// gzip header. + pub fn new(r: R) -> GzDecoder<R> { + GzDecoder { + inner: bufread::GzDecoder::new(BufReader::new(r)), + } + } +} + +impl<R> GzDecoder<R> { + /// Returns the header associated with this stream, if it was valid. + pub fn header(&self) -> Option<&GzHeader> { + self.inner.header() + } + + /// Acquires a reference to the underlying reader. + /// + /// Note that the decoder may have read past the end of the gzip data. + /// To prevent this use [`bufread::GzDecoder`] instead. + 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 continues to be used. + /// + /// Note that the decoder may have read past the end of the gzip data. + /// To prevent this use [`bufread::GzDecoder`] instead. + pub fn get_mut(&mut self) -> &mut R { + self.inner.get_mut().get_mut() + } + + /// Consumes this decoder, returning the underlying reader. + /// + /// Note that the decoder may have read past the end of the gzip data. + /// Subsequent reads will skip those bytes. To prevent this use + /// [`bufread::GzDecoder`] instead. + pub fn into_inner(self) -> R { + self.inner.into_inner().into_inner() + } +} + +impl<R: Read> Read for GzDecoder<R> { + fn read(&mut self, into: &mut [u8]) -> io::Result<usize> { + self.inner.read(into) + } +} + +impl<R: Read + Write> Write for GzDecoder<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 gzip streaming decoder that decodes a [gzip file] that may have multiple members. +/// +/// This structure implements a [`Read`] interface. When read from, it reads +/// compressed data from the underlying [`Read`] and provides the uncompressed +/// data. +/// +/// A gzip file consists of a series of *members* concatenated one after another. +/// MultiGzDecoder decodes all members of a file and returns Ok(0) once the +/// underlying reader does. +/// +/// To handle members seperately, see [GzDecoder] or read more +/// [in the introduction](../index.html#about-multi-member-gzip-files). +/// +/// [gzip file]: https://www.rfc-editor.org/rfc/rfc1952#page-5 +/// +/// # Examples +/// +/// ``` +/// use std::io::prelude::*; +/// use std::io; +/// # use flate2::Compression; +/// # use flate2::write::GzEncoder; +/// use flate2::read::MultiGzDecoder; +/// +/// # fn main() { +/// # let mut e = GzEncoder::new(Vec::new(), Compression::default()); +/// # e.write_all(b"Hello World").unwrap(); +/// # let bytes = e.finish().unwrap(); +/// # println!("{}", decode_reader(bytes).unwrap()); +/// # } +/// # +/// // Uncompresses a Gz 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 gz = MultiGzDecoder::new(&bytes[..]); +/// let mut s = String::new(); +/// gz.read_to_string(&mut s)?; +/// Ok(s) +/// } +/// ``` +#[derive(Debug)] +pub struct MultiGzDecoder<R> { + inner: bufread::MultiGzDecoder<BufReader<R>>, +} + +impl<R: Read> MultiGzDecoder<R> { + /// Creates a new decoder from the given reader, immediately parsing the + /// (first) gzip header. If the gzip stream contains multiple members all will + /// be decoded. + pub fn new(r: R) -> MultiGzDecoder<R> { + MultiGzDecoder { + inner: bufread::MultiGzDecoder::new(BufReader::new(r)), + } + } +} + +impl<R> MultiGzDecoder<R> { + /// Returns the current header associated with this stream, if it's valid. + pub fn header(&self) -> Option<&GzHeader> { + self.inner.header() + } + + /// Acquires a reference to the underlying reader. + 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. + pub fn into_inner(self) -> R { + self.inner.into_inner().into_inner() + } +} + +impl<R: Read> Read for MultiGzDecoder<R> { + fn read(&mut self, into: &mut [u8]) -> io::Result<usize> { + self.inner.read(into) + } +} + +impl<R: Read + Write> Write for MultiGzDecoder<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() + } +} + +#[cfg(test)] +mod tests { + use std::io::{Cursor, ErrorKind, Read, Result, Write}; + + use super::GzDecoder; + + //a cursor turning EOF into blocking errors + #[derive(Debug)] + pub struct BlockingCursor { + pub cursor: Cursor<Vec<u8>>, + } + + impl BlockingCursor { + pub fn new() -> BlockingCursor { + BlockingCursor { + cursor: Cursor::new(Vec::new()), + } + } + + pub fn set_position(&mut self, pos: u64) { + return self.cursor.set_position(pos); + } + } + + impl Write for BlockingCursor { + fn write(&mut self, buf: &[u8]) -> Result<usize> { + return self.cursor.write(buf); + } + fn flush(&mut self) -> Result<()> { + return self.cursor.flush(); + } + } + + impl Read for BlockingCursor { + fn read(&mut self, buf: &mut [u8]) -> Result<usize> { + //use the cursor, except it turns eof into blocking error + let r = self.cursor.read(buf); + match r { + Err(ref err) => { + if err.kind() == ErrorKind::UnexpectedEof { + return Err(ErrorKind::WouldBlock.into()); + } + } + Ok(0) => { + //regular EOF turned into blocking error + return Err(ErrorKind::WouldBlock.into()); + } + Ok(_n) => {} + } + return r; + } + } + + #[test] + 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 = GzDecoder::new(r); + let mut out = Vec::with_capacity(7); + match decoder.read(&mut out) { + Err(e) => { + assert_eq!(e.kind(), ErrorKind::WouldBlock); + } + _ => { + panic!("Unexpected result for decoder.read"); + } + } + } +} diff --git a/vendor/flate2/src/gz/write.rs b/vendor/flate2/src/gz/write.rs new file mode 100644 index 0000000..74d6c5a --- /dev/null +++ b/vendor/flate2/src/gz/write.rs @@ -0,0 +1,641 @@ +use std::cmp; +use std::io; +use std::io::prelude::*; + +use super::{corrupt, GzBuilder, GzHeader, GzHeaderParser}; +use crate::crc::{Crc, CrcWriter}; +use crate::zio; +use crate::{Compress, Compression, Decompress, Status}; + +/// A gzip streaming encoder +/// +/// This structure exposes a [`Write`] interface that will emit compressed data +/// to the underlying writer `W`. +/// +/// [`Write`]: https://doc.rust-lang.org/std/io/trait.Write.html +/// +/// # Examples +/// +/// ``` +/// use std::io::prelude::*; +/// use flate2::Compression; +/// use flate2::write::GzEncoder; +/// +/// // Vec<u8> implements Write to print the compressed bytes of sample string +/// # fn main() { +/// +/// let mut e = GzEncoder::new(Vec::new(), Compression::default()); +/// e.write_all(b"Hello World").unwrap(); +/// println!("{:?}", e.finish().unwrap()); +/// # } +/// ``` +#[derive(Debug)] +pub struct GzEncoder<W: Write> { + inner: zio::Writer<W, Compress>, + crc: Crc, + crc_bytes_written: usize, + header: Vec<u8>, +} + +pub fn gz_encoder<W: Write>(header: Vec<u8>, w: W, lvl: Compression) -> GzEncoder<W> { + GzEncoder { + inner: zio::Writer::new(w, Compress::new(lvl, false)), + crc: Crc::new(), + header, + crc_bytes_written: 0, + } +} + +impl<W: Write> GzEncoder<W> { + /// Creates a new encoder which will use the given compression level. + /// + /// The encoder is not configured specially for the emitted header. For + /// header configuration, see the `GzBuilder` type. + /// + /// The data written to the returned encoder will be compressed and then + /// written to the stream `w`. + pub fn new(w: W, level: Compression) -> GzEncoder<W> { + GzBuilder::new().write(w, level) + } + + /// 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 mutation of the writer may result in surprising results if + /// this encoder is continued to be used. + pub fn get_mut(&mut self) -> &mut W { + self.inner.get_mut() + } + + /// 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.write_header()?; + self.inner.finish()?; + + while self.crc_bytes_written < 8 { + let (sum, amt) = (self.crc.sum(), self.crc.amount()); + let buf = [ + (sum >> 0) as u8, + (sum >> 8) as u8, + (sum >> 16) as u8, + (sum >> 24) as u8, + (amt >> 0) as u8, + (amt >> 8) as u8, + (amt >> 16) as u8, + (amt >> 24) as u8, + ]; + let inner = self.inner.get_mut(); + let n = inner.write(&buf[self.crc_bytes_written..])?; + self.crc_bytes_written += n; + } + Ok(()) + } + + /// Finish encoding this stream, returning the underlying writer once the + /// encoding is done. + /// + /// 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.try_finish()?; + Ok(self.inner.take_inner()) + } + + fn write_header(&mut self) -> io::Result<()> { + while !self.header.is_empty() { + let n = self.inner.get_mut().write(&self.header)?; + self.header.drain(..n); + } + Ok(()) + } +} + +impl<W: Write> Write for GzEncoder<W> { + fn write(&mut self, buf: &[u8]) -> io::Result<usize> { + assert_eq!(self.crc_bytes_written, 0); + self.write_header()?; + let n = self.inner.write(buf)?; + self.crc.update(&buf[..n]); + Ok(n) + } + + fn flush(&mut self) -> io::Result<()> { + assert_eq!(self.crc_bytes_written, 0); + self.write_header()?; + self.inner.flush() + } +} + +impl<R: Read + Write> Read for GzEncoder<R> { + fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> { + self.get_mut().read(buf) + } +} + +impl<W: Write> Drop for GzEncoder<W> { + fn drop(&mut self) { + if self.inner.is_present() { + let _ = self.try_finish(); + } + } +} + +/// A decoder for a single member of a [gzip file]. +/// +/// This structure exposes a [`Write`] interface, receiving compressed data and +/// writing uncompressed data to the underlying writer. +/// +/// After decoding a single member of the gzip data this writer will return the number of bytes up to +/// to the end of the gzip member and subsequent writes will return Ok(0) allowing the caller to +/// handle any data following the gzip member. +/// +/// To handle gzip files that may have multiple members, see [`MultiGzDecoder`] +/// or read more +/// [in the introduction](../index.html#about-multi-member-gzip-files). +/// +/// [gzip file]: https://www.rfc-editor.org/rfc/rfc1952#page-5 +/// [`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::{GzEncoder, GzDecoder}; +/// +/// # fn main() { +/// # let mut e = GzEncoder::new(Vec::new(), Compression::default()); +/// # e.write(b"Hello World").unwrap(); +/// # let bytes = e.finish().unwrap(); +/// # assert_eq!("Hello World", decode_writer(bytes).unwrap()); +/// # } +/// // Uncompresses a gzip encoded vector of bytes and returns a string or error +/// // Here Vec<u8> implements Write +/// fn decode_writer(bytes: Vec<u8>) -> io::Result<String> { +/// let mut writer = Vec::new(); +/// let mut decoder = GzDecoder::new(writer); +/// decoder.write_all(&bytes[..])?; +/// writer = decoder.finish()?; +/// let return_string = String::from_utf8(writer).expect("String parsing error"); +/// Ok(return_string) +/// } +/// ``` +#[derive(Debug)] +pub struct GzDecoder<W: Write> { + inner: zio::Writer<CrcWriter<W>, Decompress>, + crc_bytes: Vec<u8>, + header_parser: GzHeaderParser, +} + +const CRC_BYTES_LEN: usize = 8; + +impl<W: Write> GzDecoder<W> { + /// Creates a new decoder which will write uncompressed data to the stream. + /// + /// When this encoder is dropped or unwrapped the final pieces of data will + /// be flushed. + pub fn new(w: W) -> GzDecoder<W> { + GzDecoder { + inner: zio::Writer::new(CrcWriter::new(w), Decompress::new(false)), + crc_bytes: Vec::with_capacity(CRC_BYTES_LEN), + header_parser: GzHeaderParser::new(), + } + } + + /// Returns the header associated with this stream. + pub fn header(&self) -> Option<&GzHeader> { + self.header_parser.header() + } + + /// Acquires a reference to the underlying writer. + pub fn get_ref(&self) -> &W { + self.inner.get_ref().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().get_mut() + } + + /// 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 finish the stream, returning any + /// errors which happen. + pub fn try_finish(&mut self) -> io::Result<()> { + self.finish_and_check_crc()?; + Ok(()) + } + + /// Consumes this decoder, 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.finish_and_check_crc()?; + Ok(self.inner.take_inner().into_inner()) + } + + fn finish_and_check_crc(&mut self) -> io::Result<()> { + self.inner.finish()?; + + if self.crc_bytes.len() != 8 { + return Err(corrupt()); + } + + let crc = ((self.crc_bytes[0] as u32) << 0) + | ((self.crc_bytes[1] as u32) << 8) + | ((self.crc_bytes[2] as u32) << 16) + | ((self.crc_bytes[3] as u32) << 24); + let amt = ((self.crc_bytes[4] as u32) << 0) + | ((self.crc_bytes[5] as u32) << 8) + | ((self.crc_bytes[6] as u32) << 16) + | ((self.crc_bytes[7] as u32) << 24); + if crc != self.inner.get_ref().crc().sum() { + return Err(corrupt()); + } + if amt != self.inner.get_ref().crc().amount() { + return Err(corrupt()); + } + Ok(()) + } +} + +impl<W: Write> Write for GzDecoder<W> { + fn write(&mut self, mut buf: &[u8]) -> io::Result<usize> { + let buflen = buf.len(); + if self.header().is_none() { + match self.header_parser.parse(&mut buf) { + Err(err) => { + if err.kind() == io::ErrorKind::UnexpectedEof { + // all data read but header still not complete + Ok(buflen) + } else { + Err(err) + } + } + Ok(_) => { + debug_assert!(self.header().is_some()); + // buf now contains the unread part of the original buf + let n = buflen - buf.len(); + Ok(n) + } + } + } else { + let (n, status) = self.inner.write_with_status(buf)?; + + if status == Status::StreamEnd && n < buf.len() && self.crc_bytes.len() < 8 { + let remaining = buf.len() - n; + let crc_bytes = cmp::min(remaining, CRC_BYTES_LEN - self.crc_bytes.len()); + self.crc_bytes.extend(&buf[n..n + crc_bytes]); + return Ok(n + crc_bytes); + } + Ok(n) + } + } + + fn flush(&mut self) -> io::Result<()> { + self.inner.flush() + } +} + +impl<W: Read + Write> Read for GzDecoder<W> { + fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> { + self.inner.get_mut().get_mut().read(buf) + } +} + +/// A gzip streaming decoder that decodes a [gzip file] with multiple members. +/// +/// This structure exposes a [`Write`] interface that will consume compressed data and +/// write uncompressed data to the underlying writer. +/// +/// A gzip file consists of a series of *members* concatenated one after another. +/// `MultiGzDecoder` decodes all members of a file and writes them to the +/// underlying writer one after another. +/// +/// To handle members separately, see [GzDecoder] or read more +/// [in the introduction](../index.html#about-multi-member-gzip-files). +/// +/// [gzip file]: https://www.rfc-editor.org/rfc/rfc1952#page-5 +#[derive(Debug)] +pub struct MultiGzDecoder<W: Write> { + inner: GzDecoder<W>, +} + +impl<W: Write> MultiGzDecoder<W> { + /// Creates a new decoder which will write uncompressed data to the stream. + /// If the gzip stream contains multiple members all will be decoded. + pub fn new(w: W) -> MultiGzDecoder<W> { + MultiGzDecoder { + inner: GzDecoder::new(w), + } + } + + /// Returns the header associated with the current member. + pub fn header(&self) -> Option<&GzHeader> { + self.inner.header() + } + + /// 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() + } + + /// 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 finish the stream, returning any + /// errors which happen. + pub fn try_finish(&mut self) -> io::Result<()> { + self.inner.try_finish() + } + + /// Consumes this decoder, 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(self) -> io::Result<W> { + self.inner.finish() + } +} + +impl<W: Write> Write for MultiGzDecoder<W> { + fn write(&mut self, buf: &[u8]) -> io::Result<usize> { + if buf.is_empty() { + Ok(0) + } else { + match self.inner.write(buf) { + Ok(0) => { + // When the GzDecoder indicates that it has finished + // create a new GzDecoder to handle additional data. + self.inner.try_finish()?; + let w = self.inner.inner.take_inner().into_inner(); + self.inner = GzDecoder::new(w); + self.inner.write(buf) + } + res => res, + } + } + } + + fn flush(&mut self) -> io::Result<()> { + self.inner.flush() + } +} + +#[cfg(test)] +mod tests { + use super::*; + + const STR: &str = "Hello World Hello World Hello World Hello World Hello World \ + Hello World Hello World Hello World Hello World Hello World \ + Hello World Hello World Hello World Hello World Hello World \ + Hello World Hello World Hello World Hello World Hello World \ + Hello World Hello World Hello World Hello World Hello World"; + + #[test] + fn decode_writer_one_chunk() { + let mut e = GzEncoder::new(Vec::new(), Compression::default()); + e.write(STR.as_ref()).unwrap(); + let bytes = e.finish().unwrap(); + + let mut writer = Vec::new(); + let mut decoder = GzDecoder::new(writer); + let n = decoder.write(&bytes[..]).unwrap(); + decoder.write(&bytes[n..]).unwrap(); + decoder.try_finish().unwrap(); + writer = decoder.finish().unwrap(); + let return_string = String::from_utf8(writer).expect("String parsing error"); + assert_eq!(return_string, STR); + } + + #[test] + fn decode_writer_partial_header() { + let mut e = GzEncoder::new(Vec::new(), Compression::default()); + e.write(STR.as_ref()).unwrap(); + let bytes = e.finish().unwrap(); + + let mut writer = Vec::new(); + let mut decoder = GzDecoder::new(writer); + assert_eq!(decoder.write(&bytes[..5]).unwrap(), 5); + let n = decoder.write(&bytes[5..]).unwrap(); + if n < bytes.len() - 5 { + decoder.write(&bytes[n + 5..]).unwrap(); + } + writer = decoder.finish().unwrap(); + let return_string = String::from_utf8(writer).expect("String parsing error"); + assert_eq!(return_string, STR); + } + + #[test] + fn decode_writer_partial_header_filename() { + let filename = "test.txt"; + let mut e = GzBuilder::new() + .filename(filename) + .read(STR.as_bytes(), Compression::default()); + let mut bytes = Vec::new(); + e.read_to_end(&mut bytes).unwrap(); + + let mut writer = Vec::new(); + let mut decoder = GzDecoder::new(writer); + assert_eq!(decoder.write(&bytes[..12]).unwrap(), 12); + let n = decoder.write(&bytes[12..]).unwrap(); + if n < bytes.len() - 12 { + decoder.write(&bytes[n + 12..]).unwrap(); + } + assert_eq!( + decoder.header().unwrap().filename().unwrap(), + filename.as_bytes() + ); + writer = decoder.finish().unwrap(); + let return_string = String::from_utf8(writer).expect("String parsing error"); + assert_eq!(return_string, STR); + } + + #[test] + fn decode_writer_partial_header_comment() { + let comment = "test comment"; + let mut e = GzBuilder::new() + .comment(comment) + .read(STR.as_bytes(), Compression::default()); + let mut bytes = Vec::new(); + e.read_to_end(&mut bytes).unwrap(); + + let mut writer = Vec::new(); + let mut decoder = GzDecoder::new(writer); + assert_eq!(decoder.write(&bytes[..12]).unwrap(), 12); + let n = decoder.write(&bytes[12..]).unwrap(); + if n < bytes.len() - 12 { + decoder.write(&bytes[n + 12..]).unwrap(); + } + assert_eq!( + decoder.header().unwrap().comment().unwrap(), + comment.as_bytes() + ); + writer = decoder.finish().unwrap(); + let return_string = String::from_utf8(writer).expect("String parsing error"); + assert_eq!(return_string, STR); + } + + #[test] + fn decode_writer_exact_header() { + let mut e = GzEncoder::new(Vec::new(), Compression::default()); + e.write(STR.as_ref()).unwrap(); + let bytes = e.finish().unwrap(); + + let mut writer = Vec::new(); + let mut decoder = GzDecoder::new(writer); + assert_eq!(decoder.write(&bytes[..10]).unwrap(), 10); + decoder.write(&bytes[10..]).unwrap(); + writer = decoder.finish().unwrap(); + let return_string = String::from_utf8(writer).expect("String parsing error"); + assert_eq!(return_string, STR); + } + + #[test] + fn decode_writer_partial_crc() { + let mut e = GzEncoder::new(Vec::new(), Compression::default()); + e.write(STR.as_ref()).unwrap(); + let bytes = e.finish().unwrap(); + + let mut writer = Vec::new(); + let mut decoder = GzDecoder::new(writer); + let l = bytes.len() - 5; + let n = decoder.write(&bytes[..l]).unwrap(); + decoder.write(&bytes[n..]).unwrap(); + writer = decoder.finish().unwrap(); + let return_string = String::from_utf8(writer).expect("String parsing error"); + assert_eq!(return_string, STR); + } + + // Two or more gzip files concatenated form a multi-member gzip file. MultiGzDecoder will + // concatenate the decoded contents of all members. + #[test] + fn decode_multi_writer() { + let mut e = GzEncoder::new(Vec::new(), Compression::default()); + e.write(STR.as_ref()).unwrap(); + let bytes = e.finish().unwrap().repeat(2); + + let mut writer = Vec::new(); + let mut decoder = MultiGzDecoder::new(writer); + let mut count = 0; + while count < bytes.len() { + let n = decoder.write(&bytes[count..]).unwrap(); + assert!(n != 0); + count += n; + } + writer = decoder.finish().unwrap(); + let return_string = String::from_utf8(writer).expect("String parsing error"); + let expected = STR.repeat(2); + assert_eq!(return_string, expected); + } + + // GzDecoder consumes one gzip member and then returns 0 for subsequent writes, allowing any + // additional data to be consumed by the caller. + #[test] + fn decode_extra_data() { + let compressed = { + let mut e = GzEncoder::new(Vec::new(), Compression::default()); + e.write(STR.as_ref()).unwrap(); + let mut b = e.finish().unwrap(); + b.push(b'x'); + b + }; + + let mut writer = Vec::new(); + let mut decoder = GzDecoder::new(writer); + let mut consumed_bytes = 0; + loop { + let n = decoder.write(&compressed[consumed_bytes..]).unwrap(); + if n == 0 { + break; + } + consumed_bytes += n; + } + writer = decoder.finish().unwrap(); + let actual = String::from_utf8(writer).expect("String parsing error"); + assert_eq!(actual, STR); + assert_eq!(&compressed[consumed_bytes..], b"x"); + } +} |