diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml index 81de373df..12ee4d62d 100644 --- a/.github/workflows/ci.yml +++ b/.github/workflows/ci.yml @@ -11,7 +11,7 @@ on: env: RUSTFLAGS: -Dwarnings RUST_BACKTRACE: 1 - nightly: nightly-2021-04-13 + nightly: nightly-2022-11-12 defaults: run: @@ -23,7 +23,7 @@ jobs: name: rustfmt runs-on: ubuntu-latest steps: - - uses: actions/checkout@v2 + - uses: actions/checkout@v3 - name: Install Rust run: rustup update stable - name: Check formatting @@ -35,7 +35,7 @@ jobs: # name: clippy # runs-on: ubuntu-latest # steps: - # - uses: actions/checkout@v2 + # - uses: actions/checkout@v3 # - name: Apply clippy lints # run: cargo clippy --all-features @@ -48,7 +48,7 @@ jobs: name: minrust runs-on: ubuntu-latest steps: - - uses: actions/checkout@v2 + - uses: actions/checkout@v3 - name: Install Rust run: rustup update 1.39.0 && rustup default 1.39.0 - name: Check @@ -65,7 +65,7 @@ jobs: - windows-latest runs-on: ${{ matrix.os }} steps: - - uses: actions/checkout@v2 + - uses: actions/checkout@v3 - name: Install Rust # --no-self-update is necessary because the windows environment cannot self-update rustup.exe. run: rustup update stable --no-self-update @@ -77,7 +77,7 @@ jobs: name: nightly runs-on: ubuntu-latest steps: - - uses: actions/checkout@v2 + - uses: actions/checkout@v3 - name: Install Rust run: rustup update $nightly && rustup default $nightly - name: Test @@ -96,7 +96,7 @@ jobs: - wasm32-unknown-unknown runs-on: ubuntu-latest steps: - - uses: actions/checkout@v2 + - uses: actions/checkout@v3 - name: Install Rust run: rustup update stable - name: cross build --target ${{ matrix.target }} @@ -153,7 +153,7 @@ jobs: name: tsan runs-on: ubuntu-latest steps: - - uses: actions/checkout@v2 + - uses: actions/checkout@v3 - name: Install Rust run: rustup update $nightly && rustup default $nightly - name: Install rust-src @@ -164,7 +164,7 @@ jobs: name: miri runs-on: ubuntu-latest steps: - - uses: actions/checkout@v2 + - uses: actions/checkout@v3 - name: Miri run: ci/miri.sh @@ -173,7 +173,7 @@ jobs: name: loom runs-on: ubuntu-latest steps: - - uses: actions/checkout@v2 + - uses: actions/checkout@v3 - name: Install Rust run: rustup update $nightly && rustup default $nightly - name: Loom tests @@ -192,9 +192,9 @@ jobs: - loom runs-on: ubuntu-latest steps: - - uses: actions/checkout@v2 + - uses: actions/checkout@v3 - name: Install Rust - run: rustup update stable + run: rustup update $nightly && rustup default $nightly - name: Build documentation run: cargo doc --no-deps --all-features env: diff --git a/CHANGELOG.md b/CHANGELOG.md index 99975bf89..a1bad4a40 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -1,3 +1,87 @@ +# 1.4.0 (January 31, 2023) + +### Added + +- Make `IntoIter` constructor public (#581) + +### Fixed + +- Avoid large reallocations when freezing `BytesMut` (#592) + +### Documented + +- Document which functions require `std` (#591) +- Fix duplicate "the the" typos (#585) + +# 1.3.0 (November 20, 2022) + +### Added + +- Rename and expose `BytesMut::spare_capacity_mut` (#572) +- Implement native-endian get and put functions for `Buf` and `BufMut` (#576) + +### Fixed + +- Don't have important data in unused capacity when calling reserve (#563) + +### Documented + +- `Bytes::new` etc should return `Self` not `Bytes` (#568) + +# 1.2.1 (July 30, 2022) + +### Fixed + +- Fix unbounded memory growth when using `reserve` (#560) + +# 1.2.0 (July 19, 2022) + +### Added + +- Add `BytesMut::zeroed` (#517) +- Implement `Extend` for `BytesMut` (#527) +- Add conversion from `BytesMut` to `Vec` (#543, #554) +- Add conversion from `Bytes` to `Vec` (#547) +- Add `UninitSlice::as_uninit_slice_mut()` (#548) +- Add const to `Bytes::{len,is_empty}` (#514) + +### Changed + +- Reuse vector in `BytesMut::reserve` (#539, #544) + +### Fixed + +- Make miri happy (#515, #523, #542, #545, #553) +- Make tsan happy (#541) +- Fix `remaining_mut()` on chain (#488) +- Fix amortized asymptotics of `BytesMut` (#555) + +### Documented + +- Redraw layout diagram with box drawing characters (#539) +- Clarify `BytesMut::unsplit` docs (#535) + +# 1.1.0 (August 25, 2021) + +### Added + +- `BufMut::put_bytes(self, val, cnt)` (#487) +- Implement `From>` for `Bytes` (#504) + +### Changed + +- Override `put_slice` for `&mut [u8]` (#483) +- Panic on integer overflow in `Chain::remaining` (#482) +- Add inline tags to `UninitSlice` methods (#443) +- Override `copy_to_bytes` for Chain and Take (#481) +- Keep capacity when unsplit on empty other buf (#502) + +### Documented + +- Clarify `BufMut` allocation guarantees (#501) +- Clarify `BufMut::put_int` behavior (#486) +- Clarify actions of `clear` and `truncate`. (#508) + # 1.0.1 (January 11, 2021) ### Changed diff --git a/Cargo.toml b/Cargo.toml index 34d70f8f7..4a96ec1ed 100644 --- a/Cargo.toml +++ b/Cargo.toml @@ -3,8 +3,8 @@ name = "bytes" # When releasing to crates.io: # - Update CHANGELOG.md. -# - Create "v1.0.x" git tag. -version = "1.0.1" +# - Create "v1.x.y" git tag. +version = "1.4.0" license = "MIT" authors = [ "Carl Lerche ", diff --git a/README.md b/README.md index 468485d12..be46642a4 100644 --- a/README.md +++ b/README.md @@ -36,6 +36,15 @@ Serde support is optional and disabled by default. To enable use the feature `se bytes = { version = "1", features = ["serde"] } ``` +## Building documentation + +When building the `bytes` documentation the `docsrs` option should be used, otherwise +feature gates will not be shown. This requires a nightly toolchain: + +``` +RUSTDOCFLAGS="--cfg docsrs" cargo +nightly doc +``` + ## License This project is licensed under the [MIT license](LICENSE). diff --git a/benches/buf.rs b/benches/buf.rs index 6dc8516dd..616d18748 100644 --- a/benches/buf.rs +++ b/benches/buf.rs @@ -46,7 +46,7 @@ impl TestBuf { } impl Buf for TestBuf { fn remaining(&self) -> usize { - return self.buf.len() - self.pos; + self.buf.len() - self.pos } fn advance(&mut self, cnt: usize) { self.pos += cnt; diff --git a/benches/bytes.rs b/benches/bytes.rs index c5b84124f..61d1e832a 100644 --- a/benches/bytes.rs +++ b/benches/bytes.rs @@ -88,6 +88,7 @@ fn from_long_slice(b: &mut Bencher) { #[bench] fn slice_empty(b: &mut Bencher) { b.iter(|| { + // `clone` is to convert to ARC let b = Bytes::from(vec![17; 1024]).clone(); for i in 0..1000 { test::black_box(b.slice(i % 100..i % 100)); diff --git a/ci/miri.sh b/ci/miri.sh index 88d2b6a8c..0158756cd 100755 --- a/ci/miri.sh +++ b/ci/miri.sh @@ -1,11 +1,11 @@ #!/bin/bash set -e -MIRI_NIGHTLY=nightly-$(curl -s https://rust-lang.github.io/rustup-components-history/x86_64-unknown-linux-gnu/miri) -echo "Installing latest nightly with Miri: $MIRI_NIGHTLY" -rustup set profile minimal -rustup default "$MIRI_NIGHTLY" -rustup component add miri +rustup toolchain install nightly --component miri +rustup override set nightly +cargo miri setup + +export MIRIFLAGS="-Zmiri-strict-provenance" cargo miri test cargo miri test --target mips64-unknown-linux-gnuabi64 diff --git a/ci/test-stable.sh b/ci/test-stable.sh index 212b43c7a..3b62de653 100755 --- a/ci/test-stable.sh +++ b/ci/test-stable.sh @@ -5,7 +5,8 @@ set -ex cmd="${1:-test}" # Install cargo-hack for feature flag test -cargo install cargo-hack +host=$(rustc -Vv | grep host | sed 's/host: //') +curl -LsSf https://github.com/taiki-e/cargo-hack/releases/latest/download/cargo-hack-$host.tar.gz | tar xzf - -C ~/.cargo/bin # Run with each feature # * --each-feature includes both default/no-default features diff --git a/clippy.toml b/clippy.toml new file mode 100644 index 000000000..53095b15d --- /dev/null +++ b/clippy.toml @@ -0,0 +1 @@ +msrv = "1.39" diff --git a/src/buf/buf_impl.rs b/src/buf/buf_impl.rs index 3be3a23cb..939d517cb 100644 --- a/src/buf/buf_impl.rs +++ b/src/buf/buf_impl.rs @@ -160,6 +160,7 @@ pub trait Buf { /// /// [`writev`]: http://man7.org/linux/man-pages/man2/readv.2.html #[cfg(feature = "std")] + #[cfg_attr(docsrs, doc(cfg(feature = "std")))] fn chunks_vectored<'a>(&'a self, dst: &mut [IoSlice<'a>]) -> usize { if dst.is_empty() { return 0; @@ -354,6 +355,29 @@ pub trait Buf { buf_get_impl!(self, u16::from_le_bytes); } + /// Gets an unsigned 16 bit integer from `self` in native-endian byte order. + /// + /// The current position is advanced by 2. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf: &[u8] = match cfg!(target_endian = "big") { + /// true => b"\x08\x09 hello", + /// false => b"\x09\x08 hello", + /// }; + /// assert_eq!(0x0809, buf.get_u16_ne()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_u16_ne(&mut self) -> u16 { + buf_get_impl!(self, u16::from_ne_bytes); + } + /// Gets a signed 16 bit integer from `self` in big-endian byte order. /// /// The current position is advanced by 2. @@ -394,6 +418,29 @@ pub trait Buf { buf_get_impl!(self, i16::from_le_bytes); } + /// Gets a signed 16 bit integer from `self` in native-endian byte order. + /// + /// The current position is advanced by 2. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf: &[u8] = match cfg!(target_endian = "big") { + /// true => b"\x08\x09 hello", + /// false => b"\x09\x08 hello", + /// }; + /// assert_eq!(0x0809, buf.get_i16_ne()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_i16_ne(&mut self) -> i16 { + buf_get_impl!(self, i16::from_ne_bytes); + } + /// Gets an unsigned 32 bit integer from `self` in the big-endian byte order. /// /// The current position is advanced by 4. @@ -434,6 +481,29 @@ pub trait Buf { buf_get_impl!(self, u32::from_le_bytes); } + /// Gets an unsigned 32 bit integer from `self` in native-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf: &[u8] = match cfg!(target_endian = "big") { + /// true => b"\x08\x09\xA0\xA1 hello", + /// false => b"\xA1\xA0\x09\x08 hello", + /// }; + /// assert_eq!(0x0809A0A1, buf.get_u32_ne()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_u32_ne(&mut self) -> u32 { + buf_get_impl!(self, u32::from_ne_bytes); + } + /// Gets a signed 32 bit integer from `self` in big-endian byte order. /// /// The current position is advanced by 4. @@ -474,6 +544,29 @@ pub trait Buf { buf_get_impl!(self, i32::from_le_bytes); } + /// Gets a signed 32 bit integer from `self` in native-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf: &[u8] = match cfg!(target_endian = "big") { + /// true => b"\x08\x09\xA0\xA1 hello", + /// false => b"\xA1\xA0\x09\x08 hello", + /// }; + /// assert_eq!(0x0809A0A1, buf.get_i32_ne()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_i32_ne(&mut self) -> i32 { + buf_get_impl!(self, i32::from_ne_bytes); + } + /// Gets an unsigned 64 bit integer from `self` in big-endian byte order. /// /// The current position is advanced by 8. @@ -514,6 +607,29 @@ pub trait Buf { buf_get_impl!(self, u64::from_le_bytes); } + /// Gets an unsigned 64 bit integer from `self` in native-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf: &[u8] = match cfg!(target_endian = "big") { + /// true => b"\x01\x02\x03\x04\x05\x06\x07\x08 hello", + /// false => b"\x08\x07\x06\x05\x04\x03\x02\x01 hello", + /// }; + /// assert_eq!(0x0102030405060708, buf.get_u64_ne()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_u64_ne(&mut self) -> u64 { + buf_get_impl!(self, u64::from_ne_bytes); + } + /// Gets a signed 64 bit integer from `self` in big-endian byte order. /// /// The current position is advanced by 8. @@ -554,6 +670,29 @@ pub trait Buf { buf_get_impl!(self, i64::from_le_bytes); } + /// Gets a signed 64 bit integer from `self` in native-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf: &[u8] = match cfg!(target_endian = "big") { + /// true => b"\x01\x02\x03\x04\x05\x06\x07\x08 hello", + /// false => b"\x08\x07\x06\x05\x04\x03\x02\x01 hello", + /// }; + /// assert_eq!(0x0102030405060708, buf.get_i64_ne()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_i64_ne(&mut self) -> i64 { + buf_get_impl!(self, i64::from_ne_bytes); + } + /// Gets an unsigned 128 bit integer from `self` in big-endian byte order. /// /// The current position is advanced by 16. @@ -594,6 +733,29 @@ pub trait Buf { buf_get_impl!(self, u128::from_le_bytes); } + /// Gets an unsigned 128 bit integer from `self` in native-endian byte order. + /// + /// The current position is advanced by 16. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf: &[u8] = match cfg!(target_endian = "big") { + /// true => b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16 hello", + /// false => b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02\x01 hello", + /// }; + /// assert_eq!(0x01020304050607080910111213141516, buf.get_u128_ne()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_u128_ne(&mut self) -> u128 { + buf_get_impl!(self, u128::from_ne_bytes); + } + /// Gets a signed 128 bit integer from `self` in big-endian byte order. /// /// The current position is advanced by 16. @@ -634,6 +796,29 @@ pub trait Buf { buf_get_impl!(self, i128::from_le_bytes); } + /// Gets a signed 128 bit integer from `self` in native-endian byte order. + /// + /// The current position is advanced by 16. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf: &[u8] = match cfg!(target_endian = "big") { + /// true => b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16 hello", + /// false => b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02\x01 hello", + /// }; + /// assert_eq!(0x01020304050607080910111213141516, buf.get_i128_ne()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_i128_ne(&mut self) -> i128 { + buf_get_impl!(self, i128::from_ne_bytes); + } + /// Gets an unsigned n-byte integer from `self` in big-endian byte order. /// /// The current position is advanced by `nbytes`. @@ -674,6 +859,33 @@ pub trait Buf { buf_get_impl!(le => self, u64, nbytes); } + /// Gets an unsigned n-byte integer from `self` in native-endian byte order. + /// + /// The current position is advanced by `nbytes`. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf: &[u8] = match cfg!(target_endian = "big") { + /// true => b"\x01\x02\x03 hello", + /// false => b"\x03\x02\x01 hello", + /// }; + /// assert_eq!(0x010203, buf.get_uint_ne(3)); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_uint_ne(&mut self, nbytes: usize) -> u64 { + if cfg!(target_endian = "big") { + self.get_uint(nbytes) + } else { + self.get_uint_le(nbytes) + } + } + /// Gets a signed n-byte integer from `self` in big-endian byte order. /// /// The current position is advanced by `nbytes`. @@ -714,6 +926,33 @@ pub trait Buf { buf_get_impl!(le => self, i64, nbytes); } + /// Gets a signed n-byte integer from `self` in native-endian byte order. + /// + /// The current position is advanced by `nbytes`. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf: &[u8] = match cfg!(target_endian = "big") { + /// true => b"\x01\x02\x03 hello", + /// false => b"\x03\x02\x01 hello", + /// }; + /// assert_eq!(0x010203, buf.get_int_ne(3)); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_int_ne(&mut self, nbytes: usize) -> i64 { + if cfg!(target_endian = "big") { + self.get_int(nbytes) + } else { + self.get_int_le(nbytes) + } + } + /// Gets an IEEE754 single-precision (4 bytes) floating point number from /// `self` in big-endian byte order. /// @@ -756,6 +995,30 @@ pub trait Buf { f32::from_bits(Self::get_u32_le(self)) } + /// Gets an IEEE754 single-precision (4 bytes) floating point number from + /// `self` in native-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf: &[u8] = match cfg!(target_endian = "big") { + /// true => b"\x3F\x99\x99\x9A hello", + /// false => b"\x9A\x99\x99\x3F hello", + /// }; + /// assert_eq!(1.2f32, buf.get_f32_ne()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_f32_ne(&mut self) -> f32 { + f32::from_bits(Self::get_u32_ne(self)) + } + /// Gets an IEEE754 double-precision (8 bytes) floating point number from /// `self` in big-endian byte order. /// @@ -798,6 +1061,30 @@ pub trait Buf { f64::from_bits(Self::get_u64_le(self)) } + /// Gets an IEEE754 double-precision (8 bytes) floating point number from + /// `self` in native-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf: &[u8] = match cfg!(target_endian = "big") { + /// true => b"\x3F\xF3\x33\x33\x33\x33\x33\x33 hello", + /// false => b"\x33\x33\x33\x33\x33\x33\xF3\x3F hello", + /// }; + /// assert_eq!(1.2f64, buf.get_f64_ne()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_f64_ne(&mut self) -> f64 { + f64::from_bits(Self::get_u64_ne(self)) + } + /// Consumes `len` bytes inside self and returns new instance of `Bytes` /// with this data. /// @@ -898,6 +1185,7 @@ pub trait Buf { /// assert_eq!(&dst[..11], &b"hello world"[..]); /// ``` #[cfg(feature = "std")] + #[cfg_attr(docsrs, doc(cfg(feature = "std")))] fn reader(self) -> Reader where Self: Sized, @@ -949,6 +1237,10 @@ macro_rules! deref_forward_buf { (**self).get_u16_le() } + fn get_u16_ne(&mut self) -> u16 { + (**self).get_u16_ne() + } + fn get_i16(&mut self) -> i16 { (**self).get_i16() } @@ -957,6 +1249,10 @@ macro_rules! deref_forward_buf { (**self).get_i16_le() } + fn get_i16_ne(&mut self) -> i16 { + (**self).get_i16_ne() + } + fn get_u32(&mut self) -> u32 { (**self).get_u32() } @@ -965,6 +1261,10 @@ macro_rules! deref_forward_buf { (**self).get_u32_le() } + fn get_u32_ne(&mut self) -> u32 { + (**self).get_u32_ne() + } + fn get_i32(&mut self) -> i32 { (**self).get_i32() } @@ -973,6 +1273,10 @@ macro_rules! deref_forward_buf { (**self).get_i32_le() } + fn get_i32_ne(&mut self) -> i32 { + (**self).get_i32_ne() + } + fn get_u64(&mut self) -> u64 { (**self).get_u64() } @@ -981,6 +1285,10 @@ macro_rules! deref_forward_buf { (**self).get_u64_le() } + fn get_u64_ne(&mut self) -> u64 { + (**self).get_u64_ne() + } + fn get_i64(&mut self) -> i64 { (**self).get_i64() } @@ -989,6 +1297,10 @@ macro_rules! deref_forward_buf { (**self).get_i64_le() } + fn get_i64_ne(&mut self) -> i64 { + (**self).get_i64_ne() + } + fn get_uint(&mut self, nbytes: usize) -> u64 { (**self).get_uint(nbytes) } @@ -997,6 +1309,10 @@ macro_rules! deref_forward_buf { (**self).get_uint_le(nbytes) } + fn get_uint_ne(&mut self, nbytes: usize) -> u64 { + (**self).get_uint_ne(nbytes) + } + fn get_int(&mut self, nbytes: usize) -> i64 { (**self).get_int(nbytes) } @@ -1005,6 +1321,10 @@ macro_rules! deref_forward_buf { (**self).get_int_le(nbytes) } + fn get_int_ne(&mut self, nbytes: usize) -> i64 { + (**self).get_int_ne(nbytes) + } + #[cfg(not(bytes_no_atomic_cas))] fn copy_to_bytes(&mut self, len: usize) -> crate::Bytes { (**self).copy_to_bytes(len) diff --git a/src/buf/buf_mut.rs b/src/buf/buf_mut.rs index bf33fe635..2a3c24325 100644 --- a/src/buf/buf_mut.rs +++ b/src/buf/buf_mut.rs @@ -56,6 +56,10 @@ pub unsafe trait BufMut { /// Implementations of `remaining_mut` should ensure that the return value /// does not change unless a call is made to `advance_mut` or any other /// function that is documented to change the `BufMut`'s current position. + /// + /// # Note + /// + /// `remaining_mut` may return value smaller than actual available space. fn remaining_mut(&self) -> usize; /// Advance the internal cursor of the BufMut @@ -261,6 +265,37 @@ pub unsafe trait BufMut { } } + /// Put `cnt` bytes `val` into `self`. + /// + /// Logically equivalent to calling `self.put_u8(val)` `cnt` times, but may work faster. + /// + /// `self` must have at least `cnt` remaining capacity. + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut dst = [0; 6]; + /// + /// { + /// let mut buf = &mut dst[..]; + /// buf.put_bytes(b'a', 4); + /// + /// assert_eq!(2, buf.remaining_mut()); + /// } + /// + /// assert_eq!(b"aaaa\0\0", &dst); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_bytes(&mut self, val: u8, cnt: usize) { + for _ in 0..cnt { + self.put_u8(val); + } + } + /// Writes an unsigned 8 bit integer to `self`. /// /// The current position is advanced by 1. @@ -351,6 +386,32 @@ pub unsafe trait BufMut { self.put_slice(&n.to_le_bytes()) } + /// Writes an unsigned 16 bit integer to `self` in native-endian byte order. + /// + /// The current position is advanced by 2. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u16_ne(0x0809); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x08\x09"); + /// } else { + /// assert_eq!(buf, b"\x09\x08"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u16_ne(&mut self, n: u16) { + self.put_slice(&n.to_ne_bytes()) + } + /// Writes a signed 16 bit integer to `self` in big-endian byte order. /// /// The current position is advanced by 2. @@ -395,6 +456,32 @@ pub unsafe trait BufMut { self.put_slice(&n.to_le_bytes()) } + /// Writes a signed 16 bit integer to `self` in native-endian byte order. + /// + /// The current position is advanced by 2. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i16_ne(0x0809); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x08\x09"); + /// } else { + /// assert_eq!(buf, b"\x09\x08"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i16_ne(&mut self, n: i16) { + self.put_slice(&n.to_ne_bytes()) + } + /// Writes an unsigned 32 bit integer to `self` in big-endian byte order. /// /// The current position is advanced by 4. @@ -439,6 +526,32 @@ pub unsafe trait BufMut { self.put_slice(&n.to_le_bytes()) } + /// Writes an unsigned 32 bit integer to `self` in native-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u32_ne(0x0809A0A1); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x08\x09\xA0\xA1"); + /// } else { + /// assert_eq!(buf, b"\xA1\xA0\x09\x08"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u32_ne(&mut self, n: u32) { + self.put_slice(&n.to_ne_bytes()) + } + /// Writes a signed 32 bit integer to `self` in big-endian byte order. /// /// The current position is advanced by 4. @@ -483,6 +596,32 @@ pub unsafe trait BufMut { self.put_slice(&n.to_le_bytes()) } + /// Writes a signed 32 bit integer to `self` in native-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i32_ne(0x0809A0A1); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x08\x09\xA0\xA1"); + /// } else { + /// assert_eq!(buf, b"\xA1\xA0\x09\x08"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i32_ne(&mut self, n: i32) { + self.put_slice(&n.to_ne_bytes()) + } + /// Writes an unsigned 64 bit integer to `self` in the big-endian byte order. /// /// The current position is advanced by 8. @@ -527,6 +666,32 @@ pub unsafe trait BufMut { self.put_slice(&n.to_le_bytes()) } + /// Writes an unsigned 64 bit integer to `self` in native-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u64_ne(0x0102030405060708); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08"); + /// } else { + /// assert_eq!(buf, b"\x08\x07\x06\x05\x04\x03\x02\x01"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u64_ne(&mut self, n: u64) { + self.put_slice(&n.to_ne_bytes()) + } + /// Writes a signed 64 bit integer to `self` in the big-endian byte order. /// /// The current position is advanced by 8. @@ -571,6 +736,32 @@ pub unsafe trait BufMut { self.put_slice(&n.to_le_bytes()) } + /// Writes a signed 64 bit integer to `self` in native-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i64_ne(0x0102030405060708); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08"); + /// } else { + /// assert_eq!(buf, b"\x08\x07\x06\x05\x04\x03\x02\x01"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i64_ne(&mut self, n: i64) { + self.put_slice(&n.to_ne_bytes()) + } + /// Writes an unsigned 128 bit integer to `self` in the big-endian byte order. /// /// The current position is advanced by 16. @@ -615,6 +806,32 @@ pub unsafe trait BufMut { self.put_slice(&n.to_le_bytes()) } + /// Writes an unsigned 128 bit integer to `self` in native-endian byte order. + /// + /// The current position is advanced by 16. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u128_ne(0x01020304050607080910111213141516); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16"); + /// } else { + /// assert_eq!(buf, b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02\x01"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u128_ne(&mut self, n: u128) { + self.put_slice(&n.to_ne_bytes()) + } + /// Writes a signed 128 bit integer to `self` in the big-endian byte order. /// /// The current position is advanced by 16. @@ -659,6 +876,32 @@ pub unsafe trait BufMut { self.put_slice(&n.to_le_bytes()) } + /// Writes a signed 128 bit integer to `self` in native-endian byte order. + /// + /// The current position is advanced by 16. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i128_ne(0x01020304050607080910111213141516); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16"); + /// } else { + /// assert_eq!(buf, b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02\x01"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i128_ne(&mut self, n: i128) { + self.put_slice(&n.to_ne_bytes()) + } + /// Writes an unsigned n-byte integer to `self` in big-endian byte order. /// /// The current position is advanced by `nbytes`. @@ -703,7 +946,7 @@ pub unsafe trait BufMut { self.put_slice(&n.to_le_bytes()[0..nbytes]); } - /// Writes a signed n-byte integer to `self` in big-endian byte order. + /// Writes an unsigned n-byte integer to `self` in the native-endian byte order. /// /// The current position is advanced by `nbytes`. /// @@ -713,19 +956,49 @@ pub unsafe trait BufMut { /// use bytes::BufMut; /// /// let mut buf = vec![]; - /// buf.put_int(0x010203, 3); - /// assert_eq!(buf, b"\x01\x02\x03"); + /// buf.put_uint_ne(0x010203, 3); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x01\x02\x03"); + /// } else { + /// assert_eq!(buf, b"\x03\x02\x01"); + /// } /// ``` /// /// # Panics /// /// This function panics if there is not enough remaining capacity in /// `self`. + fn put_uint_ne(&mut self, n: u64, nbytes: usize) { + if cfg!(target_endian = "big") { + self.put_uint(n, nbytes) + } else { + self.put_uint_le(n, nbytes) + } + } + + /// Writes low `nbytes` of a signed integer to `self` in big-endian byte order. + /// + /// The current position is advanced by `nbytes`. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_int(0x0504010203, 3); + /// assert_eq!(buf, b"\x01\x02\x03"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self` or if `nbytes` is greater than 8. fn put_int(&mut self, n: i64, nbytes: usize) { self.put_slice(&n.to_be_bytes()[mem::size_of_val(&n) - nbytes..]); } - /// Writes a signed n-byte integer to `self` in little-endian byte order. + /// Writes low `nbytes` of a signed integer to `self` in little-endian byte order. /// /// The current position is advanced by `nbytes`. /// @@ -735,18 +1008,48 @@ pub unsafe trait BufMut { /// use bytes::BufMut; /// /// let mut buf = vec![]; - /// buf.put_int_le(0x010203, 3); + /// buf.put_int_le(0x0504010203, 3); /// assert_eq!(buf, b"\x03\x02\x01"); /// ``` /// /// # Panics /// /// This function panics if there is not enough remaining capacity in - /// `self`. + /// `self` or if `nbytes` is greater than 8. fn put_int_le(&mut self, n: i64, nbytes: usize) { self.put_slice(&n.to_le_bytes()[0..nbytes]); } + /// Writes low `nbytes` of a signed integer to `self` in native-endian byte order. + /// + /// The current position is advanced by `nbytes`. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_int_ne(0x010203, 3); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x01\x02\x03"); + /// } else { + /// assert_eq!(buf, b"\x03\x02\x01"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self` or if `nbytes` is greater than 8. + fn put_int_ne(&mut self, n: i64, nbytes: usize) { + if cfg!(target_endian = "big") { + self.put_int(n, nbytes) + } else { + self.put_int_le(n, nbytes) + } + } + /// Writes an IEEE754 single-precision (4 bytes) floating point number to /// `self` in big-endian byte order. /// @@ -793,6 +1096,33 @@ pub unsafe trait BufMut { self.put_u32_le(n.to_bits()); } + /// Writes an IEEE754 single-precision (4 bytes) floating point number to + /// `self` in native-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_f32_ne(1.2f32); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x3F\x99\x99\x9A"); + /// } else { + /// assert_eq!(buf, b"\x9A\x99\x99\x3F"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_f32_ne(&mut self, n: f32) { + self.put_u32_ne(n.to_bits()); + } + /// Writes an IEEE754 double-precision (8 bytes) floating point number to /// `self` in big-endian byte order. /// @@ -839,6 +1169,33 @@ pub unsafe trait BufMut { self.put_u64_le(n.to_bits()); } + /// Writes an IEEE754 double-precision (8 bytes) floating point number to + /// `self` in native-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_f64_ne(1.2f64); + /// if cfg!(target_endian = "big") { + /// assert_eq!(buf, b"\x3F\xF3\x33\x33\x33\x33\x33\x33"); + /// } else { + /// assert_eq!(buf, b"\x33\x33\x33\x33\x33\x33\xF3\x3F"); + /// } + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_f64_ne(&mut self, n: f64) { + self.put_u64_ne(n.to_bits()); + } + /// Creates an adaptor which can write at most `limit` bytes to `self`. /// /// # Examples @@ -882,6 +1239,7 @@ pub unsafe trait BufMut { /// assert_eq!(*buf, b"hello world"[..]); /// ``` #[cfg(feature = "std")] + #[cfg_attr(docsrs, doc(cfg(feature = "std")))] fn writer(self) -> Writer where Self: Sized, @@ -951,6 +1309,10 @@ macro_rules! deref_forward_bufmut { (**self).put_u16_le(n) } + fn put_u16_ne(&mut self, n: u16) { + (**self).put_u16_ne(n) + } + fn put_i16(&mut self, n: i16) { (**self).put_i16(n) } @@ -959,6 +1321,10 @@ macro_rules! deref_forward_bufmut { (**self).put_i16_le(n) } + fn put_i16_ne(&mut self, n: i16) { + (**self).put_i16_ne(n) + } + fn put_u32(&mut self, n: u32) { (**self).put_u32(n) } @@ -967,6 +1333,10 @@ macro_rules! deref_forward_bufmut { (**self).put_u32_le(n) } + fn put_u32_ne(&mut self, n: u32) { + (**self).put_u32_ne(n) + } + fn put_i32(&mut self, n: i32) { (**self).put_i32(n) } @@ -975,6 +1345,10 @@ macro_rules! deref_forward_bufmut { (**self).put_i32_le(n) } + fn put_i32_ne(&mut self, n: i32) { + (**self).put_i32_ne(n) + } + fn put_u64(&mut self, n: u64) { (**self).put_u64(n) } @@ -983,6 +1357,10 @@ macro_rules! deref_forward_bufmut { (**self).put_u64_le(n) } + fn put_u64_ne(&mut self, n: u64) { + (**self).put_u64_ne(n) + } + fn put_i64(&mut self, n: i64) { (**self).put_i64(n) } @@ -990,6 +1368,10 @@ macro_rules! deref_forward_bufmut { fn put_i64_le(&mut self, n: i64) { (**self).put_i64_le(n) } + + fn put_i64_ne(&mut self, n: i64) { + (**self).put_i64_ne(n) + } }; } @@ -1027,6 +1409,49 @@ unsafe impl BufMut for &mut [u8] { self.advance_mut(src.len()); } } + + fn put_bytes(&mut self, val: u8, cnt: usize) { + assert!(self.remaining_mut() >= cnt); + unsafe { + ptr::write_bytes(self.as_mut_ptr(), val, cnt); + self.advance_mut(cnt); + } + } +} + +unsafe impl BufMut for &mut [core::mem::MaybeUninit] { + #[inline] + fn remaining_mut(&self) -> usize { + self.len() + } + + #[inline] + fn chunk_mut(&mut self) -> &mut UninitSlice { + UninitSlice::from_uninit_slice(self) + } + + #[inline] + unsafe fn advance_mut(&mut self, cnt: usize) { + // Lifetime dance taken from `impl Write for &mut [u8]`. + let (_, b) = core::mem::replace(self, &mut []).split_at_mut(cnt); + *self = b; + } + + #[inline] + fn put_slice(&mut self, src: &[u8]) { + self.chunk_mut()[..src.len()].copy_from_slice(src); + unsafe { + self.advance_mut(src.len()); + } + } + + fn put_bytes(&mut self, val: u8, cnt: usize) { + assert!(self.remaining_mut() >= cnt); + unsafe { + ptr::write_bytes(self.as_mut_ptr() as *mut u8, val, cnt); + self.advance_mut(cnt); + } + } } unsafe impl BufMut for Vec { @@ -1091,6 +1516,11 @@ unsafe impl BufMut for Vec { fn put_slice(&mut self, src: &[u8]) { self.extend_from_slice(src); } + + fn put_bytes(&mut self, val: u8, cnt: usize) { + let new_len = self.len().checked_add(cnt).unwrap(); + self.resize(new_len, val); + } } // The existence of this function makes the compiler catch if the BufMut diff --git a/src/buf/chain.rs b/src/buf/chain.rs index a87d7c9a0..8b058d263 100644 --- a/src/buf/chain.rs +++ b/src/buf/chain.rs @@ -199,8 +199,7 @@ where fn remaining_mut(&self) -> usize { self.a .remaining_mut() - .checked_add(self.b.remaining_mut()) - .unwrap() + .saturating_add(self.b.remaining_mut()) } fn chunk_mut(&mut self) -> &mut UninitSlice { diff --git a/src/buf/iter.rs b/src/buf/iter.rs index 8914a40e8..c694e3d41 100644 --- a/src/buf/iter.rs +++ b/src/buf/iter.rs @@ -2,8 +2,6 @@ use crate::Buf; /// Iterator over the bytes contained by the buffer. /// -/// This struct is created by the [`iter`] method on [`Buf`]. -/// /// # Examples /// /// Basic usage: @@ -43,7 +41,7 @@ impl IntoIter { /// assert_eq!(iter.next(), Some(b'c')); /// assert_eq!(iter.next(), None); /// ``` - pub(crate) fn new(inner: T) -> IntoIter { + pub fn new(inner: T) -> IntoIter { IntoIter { inner } } diff --git a/src/buf/uninit_slice.rs b/src/buf/uninit_slice.rs index fb67c0afd..84b1d8820 100644 --- a/src/buf/uninit_slice.rs +++ b/src/buf/uninit_slice.rs @@ -22,6 +22,44 @@ use core::ops::{ pub struct UninitSlice([MaybeUninit]); impl UninitSlice { + /// Creates a `&mut UninitSlice` wrapping slice of uninitialised memory. + /// + /// # Examples + /// + /// ``` + /// use bytes::buf::UninitSlice; + /// use core::mem::MaybeUninit; + /// + /// let mut buffer = [MaybeUninit::uninit(); 64]; + /// let slice = UninitSlice::from_uninit_slice(&mut buffer[..]); + /// + /// let mut vec = Vec::with_capacity(1024); + /// let spare: &mut UninitSlice = vec.spare_capacity_mut().into(); + /// ``` + #[inline] + pub fn from_uninit_slice(slice: &mut [MaybeUninit]) -> &mut UninitSlice { + unsafe { &mut *(slice as *mut [MaybeUninit] as *mut UninitSlice) } + } + + fn from_uninit_slice_ref(slice: &[MaybeUninit]) -> &UninitSlice { + unsafe { &*(slice as *const [MaybeUninit] as *const UninitSlice) } + } + + /// Creates a `&mut UninitSlice` wrapping slice of initialised memory. + /// + /// # Examples + /// + /// ``` + /// use bytes::buf::UninitSlice; + /// + /// let mut buffer = [0u8; 64]; + /// let slice = UninitSlice::from_slice(&mut buffer[..]); + /// ``` + #[inline] + pub fn from_slice(slice: &mut [u8]) -> &mut UninitSlice { + unsafe { &mut *(slice as *mut [u8] as *mut [MaybeUninit] as *mut UninitSlice) } + } + /// Create a `&mut UninitSlice` from a pointer and a length. /// /// # Safety @@ -44,7 +82,7 @@ impl UninitSlice { pub unsafe fn from_raw_parts_mut<'a>(ptr: *mut u8, len: usize) -> &'a mut UninitSlice { let maybe_init: &mut [MaybeUninit] = core::slice::from_raw_parts_mut(ptr as *mut _, len); - &mut *(maybe_init as *mut [MaybeUninit] as *mut UninitSlice) + Self::from_uninit_slice(maybe_init) } /// Write a single byte at the specified offset. @@ -124,6 +162,32 @@ impl UninitSlice { self.0.as_mut_ptr() as *mut _ } + /// Return a `&mut [MaybeUninit]` to this slice's buffer. + /// + /// # Safety + /// + /// The caller **must not** read from the referenced memory and **must not** write + /// **uninitialized** bytes to the slice either. This is because `BufMut` implementation + /// that created the `UninitSlice` knows which parts are initialized. Writing uninitalized + /// bytes to the slice may cause the `BufMut` to read those bytes and trigger undefined + /// behavior. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut data = [0, 1, 2]; + /// let mut slice = &mut data[..]; + /// unsafe { + /// let uninit_slice = BufMut::chunk_mut(&mut slice).as_uninit_slice_mut(); + /// }; + /// ``` + #[inline] + pub unsafe fn as_uninit_slice_mut<'a>(&'a mut self) -> &'a mut [MaybeUninit] { + &mut *(self as *mut _ as *mut [MaybeUninit]) + } + /// Returns the number of bytes in the slice. /// /// # Examples @@ -149,6 +213,18 @@ impl fmt::Debug for UninitSlice { } } +impl<'a> From<&'a mut [u8]> for &'a mut UninitSlice { + fn from(slice: &'a mut [u8]) -> Self { + UninitSlice::from_slice(slice) + } +} + +impl<'a> From<&'a mut [MaybeUninit]> for &'a mut UninitSlice { + fn from(slice: &'a mut [MaybeUninit]) -> Self { + UninitSlice::from_uninit_slice(slice) + } +} + macro_rules! impl_index { ($($t:ty),*) => { $( @@ -157,16 +233,14 @@ macro_rules! impl_index { #[inline] fn index(&self, index: $t) -> &UninitSlice { - let maybe_uninit: &[MaybeUninit] = &self.0[index]; - unsafe { &*(maybe_uninit as *const [MaybeUninit] as *const UninitSlice) } + UninitSlice::from_uninit_slice_ref(&self.0[index]) } } impl IndexMut<$t> for UninitSlice { #[inline] fn index_mut(&mut self, index: $t) -> &mut UninitSlice { - let maybe_uninit: &mut [MaybeUninit] = &mut self.0[index]; - unsafe { &mut *(maybe_uninit as *mut [MaybeUninit] as *mut UninitSlice) } + UninitSlice::from_uninit_slice(&mut self.0[index]) } } )* diff --git a/src/bytes.rs b/src/bytes.rs index b1b35ea83..0404a72db 100644 --- a/src/bytes.rs +++ b/src/bytes.rs @@ -2,12 +2,18 @@ use core::iter::FromIterator; use core::ops::{Deref, RangeBounds}; use core::{cmp, fmt, hash, mem, ptr, slice, usize}; -use alloc::{borrow::Borrow, boxed::Box, string::String, vec::Vec}; +use alloc::{ + alloc::{dealloc, Layout}, + borrow::Borrow, + boxed::Box, + string::String, + vec::Vec, +}; use crate::buf::IntoIter; #[allow(unused)] use crate::loom::sync::atomic::AtomicMut; -use crate::loom::sync::atomic::{self, AtomicPtr, AtomicUsize, Ordering}; +use crate::loom::sync::atomic::{AtomicPtr, AtomicUsize, Ordering}; use crate::Buf; /// A cheaply cloneable and sliceable chunk of contiguous memory. @@ -26,7 +32,7 @@ use crate::Buf; /// All `Bytes` implementations must fulfill the following requirements: /// - They are cheaply cloneable and thereby shareable between an unlimited amount /// of components, for example by modifying a reference count. -/// - Instances can be sliced to refer to a subset of the the original buffer. +/// - Instances can be sliced to refer to a subset of the original buffer. /// /// ``` /// use bytes::Bytes; @@ -55,7 +61,7 @@ use crate::Buf; /// # Sharing /// /// `Bytes` contains a vtable, which allows implementations of `Bytes` to define -/// how sharing/cloneing is implemented in detail. +/// how sharing/cloning is implemented in detail. /// When `Bytes::clone()` is called, `Bytes` will call the vtable function for /// cloning the backing storage in order to share it behind between multiple /// `Bytes` instances. @@ -65,7 +71,7 @@ use crate::Buf; /// /// For `Bytes` implementations which point to a reference counted shared storage /// (e.g. an `Arc<[u8]>`), sharing will be implemented by increasing the -/// the reference count. +/// reference count. /// /// Due to this mechanism, multiple `Bytes` instances may point to the same /// shared memory region. @@ -78,18 +84,18 @@ use crate::Buf; /// /// ```text /// -/// Arc ptrs +---------+ -/// ________________________ / | Bytes 2 | -/// / +---------+ -/// / +-----------+ | | -/// |_________/ | Bytes 1 | | | -/// | +-----------+ | | +/// Arc ptrs ┌─────────┐ +/// ________________________ / │ Bytes 2 │ +/// / └─────────┘ +/// / ┌───────────┐ | | +/// |_________/ │ Bytes 1 │ | | +/// | └───────────┘ | | /// | | | ___/ data | tail /// | data | tail |/ | /// v v v v -/// +-----+---------------------------------+-----+ -/// | Arc | | | | | -/// +-----+---------------------------------+-----+ +/// ┌─────┬─────┬───────────┬───────────────┬─────┐ +/// │ Arc │ │ │ │ │ +/// └─────┴─────┴───────────┴───────────────┴─────┘ /// ``` pub struct Bytes { ptr: *const u8, @@ -103,6 +109,10 @@ pub(crate) struct Vtable { /// fn(data, ptr, len) pub clone: unsafe fn(&AtomicPtr<()>, *const u8, usize) -> Bytes, /// fn(data, ptr, len) + /// + /// takes `Bytes` to value + pub to_vec: unsafe fn(&AtomicPtr<()>, *const u8, usize) -> Vec, + /// fn(data, ptr, len) pub drop: unsafe fn(&mut AtomicPtr<()>, *const u8, usize), } @@ -121,7 +131,7 @@ impl Bytes { /// ``` #[inline] #[cfg(not(all(loom, test)))] - pub const fn new() -> Bytes { + pub const fn new() -> Self { // Make it a named const to work around // "unsizing casts are not allowed in const fn" const EMPTY: &[u8] = &[]; @@ -129,7 +139,7 @@ impl Bytes { } #[cfg(all(loom, test))] - pub fn new() -> Bytes { + pub fn new() -> Self { const EMPTY: &[u8] = &[]; Bytes::from_static(EMPTY) } @@ -149,7 +159,7 @@ impl Bytes { /// ``` #[inline] #[cfg(not(all(loom, test)))] - pub const fn from_static(bytes: &'static [u8]) -> Bytes { + pub const fn from_static(bytes: &'static [u8]) -> Self { Bytes { ptr: bytes.as_ptr(), len: bytes.len(), @@ -159,7 +169,7 @@ impl Bytes { } #[cfg(all(loom, test))] - pub fn from_static(bytes: &'static [u8]) -> Bytes { + pub fn from_static(bytes: &'static [u8]) -> Self { Bytes { ptr: bytes.as_ptr(), len: bytes.len(), @@ -179,7 +189,7 @@ impl Bytes { /// assert_eq!(b.len(), 5); /// ``` #[inline] - pub fn len(&self) -> usize { + pub const fn len(&self) -> usize { self.len } @@ -194,7 +204,7 @@ impl Bytes { /// assert!(b.is_empty()); /// ``` #[inline] - pub fn is_empty(&self) -> bool { + pub const fn is_empty(&self) -> bool { self.len == 0 } @@ -225,7 +235,7 @@ impl Bytes { /// /// Requires that `begin <= end` and `end <= self.len()`, otherwise slicing /// will panic. - pub fn slice(&self, range: impl RangeBounds) -> Bytes { + pub fn slice(&self, range: impl RangeBounds) -> Self { use core::ops::Bound; let len = self.len(); @@ -262,7 +272,7 @@ impl Bytes { let mut ret = self.clone(); ret.len = end - begin; - ret.ptr = unsafe { ret.ptr.offset(begin as isize) }; + ret.ptr = unsafe { ret.ptr.add(begin) }; ret } @@ -292,7 +302,7 @@ impl Bytes { /// /// Requires that the given `sub` slice is in fact contained within the /// `Bytes` buffer; otherwise this function will panic. - pub fn slice_ref(&self, subset: &[u8]) -> Bytes { + pub fn slice_ref(&self, subset: &[u8]) -> Self { // Empty slice and empty Bytes may have their pointers reset // so explicitly allow empty slice to be a subslice of any slice. if subset.is_empty() { @@ -308,15 +318,15 @@ impl Bytes { assert!( sub_p >= bytes_p, "subset pointer ({:p}) is smaller than self pointer ({:p})", - sub_p as *const u8, - bytes_p as *const u8, + subset.as_ptr(), + self.as_ptr(), ); assert!( sub_p + sub_len <= bytes_p + bytes_len, "subset is out of bounds: self = ({:p}, {}), subset = ({:p}, {})", - bytes_p as *const u8, + self.as_ptr(), bytes_len, - sub_p as *const u8, + subset.as_ptr(), sub_len, ); @@ -349,7 +359,7 @@ impl Bytes { /// /// Panics if `at > len`. #[must_use = "consider Bytes::truncate if you don't need the other half"] - pub fn split_off(&mut self, at: usize) -> Bytes { + pub fn split_off(&mut self, at: usize) -> Self { assert!( at <= self.len(), "split_off out of bounds: {:?} <= {:?}", @@ -398,7 +408,7 @@ impl Bytes { /// /// Panics if `at > len`. #[must_use = "consider Bytes::advance if you don't need the other half"] - pub fn split_to(&mut self, at: usize) -> Bytes { + pub fn split_to(&mut self, at: usize) -> Self { assert!( at <= self.len(), "split_to out of bounds: {:?} <= {:?}", @@ -501,7 +511,7 @@ impl Bytes { // should already be asserted, but debug assert for tests debug_assert!(self.len >= by, "internal: inc_start out of bounds"); self.len -= by; - self.ptr = self.ptr.offset(by as isize); + self.ptr = self.ptr.add(by); } } @@ -604,7 +614,7 @@ impl<'a> IntoIterator for &'a Bytes { type IntoIter = core::slice::Iter<'a, u8>; fn into_iter(self) -> Self::IntoIter { - self.as_slice().into_iter() + self.as_slice().iter() } } @@ -686,7 +696,7 @@ impl PartialOrd for str { impl PartialEq> for Bytes { fn eq(&self, other: &Vec) -> bool { - *self == &other[..] + *self == other[..] } } @@ -710,7 +720,7 @@ impl PartialOrd for Vec { impl PartialEq for Bytes { fn eq(&self, other: &String) -> bool { - *self == &other[..] + *self == other[..] } } @@ -797,30 +807,64 @@ impl From<&'static str> for Bytes { impl From> for Bytes { fn from(vec: Vec) -> Bytes { - // into_boxed_slice doesn't return a heap allocation for empty vectors, + let mut vec = vec; + let ptr = vec.as_mut_ptr(); + let len = vec.len(); + let cap = vec.capacity(); + + // Avoid an extra allocation if possible. + if len == cap { + return Bytes::from(vec.into_boxed_slice()); + } + + let shared = Box::new(Shared { + buf: ptr, + cap, + ref_cnt: AtomicUsize::new(1), + }); + mem::forget(vec); + + let shared = Box::into_raw(shared); + // The pointer should be aligned, so this assert should + // always succeed. + debug_assert!( + 0 == (shared as usize & KIND_MASK), + "internal: Box should have an aligned pointer", + ); + Bytes { + ptr, + len, + data: AtomicPtr::new(shared as _), + vtable: &SHARED_VTABLE, + } + } +} + +impl From> for Bytes { + fn from(slice: Box<[u8]>) -> Bytes { + // Box<[u8]> doesn't contain a heap allocation for empty slices, // so the pointer isn't aligned enough for the KIND_VEC stashing to // work. - if vec.is_empty() { + if slice.is_empty() { return Bytes::new(); } - let slice = vec.into_boxed_slice(); let len = slice.len(); let ptr = Box::into_raw(slice) as *mut u8; if ptr as usize & 0x1 == 0 { - let data = ptr as usize | KIND_VEC; + let data = ptr_map(ptr, |addr| addr | KIND_VEC); Bytes { ptr, len, - data: AtomicPtr::new(data as *mut _), + data: AtomicPtr::new(data.cast()), vtable: &PROMOTABLE_EVEN_VTABLE, } } else { Bytes { ptr, len, - data: AtomicPtr::new(ptr as *mut _), + data: AtomicPtr::new(ptr.cast()), vtable: &PROMOTABLE_ODD_VTABLE, } } @@ -833,6 +877,13 @@ impl From for Bytes { } } +impl From for Vec { + fn from(bytes: Bytes) -> Vec { + let bytes = mem::ManuallyDrop::new(bytes); + unsafe { (bytes.vtable.to_vec)(&bytes.data, bytes.ptr, bytes.len) } + } +} + // ===== impl Vtable ===== impl fmt::Debug for Vtable { @@ -848,6 +899,7 @@ impl fmt::Debug for Vtable { const STATIC_VTABLE: Vtable = Vtable { clone: static_clone, + to_vec: static_to_vec, drop: static_drop, }; @@ -856,6 +908,11 @@ unsafe fn static_clone(_: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Bytes { Bytes::from_static(slice) } +unsafe fn static_to_vec(_: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Vec { + let slice = slice::from_raw_parts(ptr, len); + slice.to_vec() +} + unsafe fn static_drop(_: &mut AtomicPtr<()>, _: *const u8, _: usize) { // nothing to drop for &'static [u8] } @@ -864,11 +921,13 @@ unsafe fn static_drop(_: &mut AtomicPtr<()>, _: *const u8, _: usize) { static PROMOTABLE_EVEN_VTABLE: Vtable = Vtable { clone: promotable_even_clone, + to_vec: promotable_even_to_vec, drop: promotable_even_drop, }; static PROMOTABLE_ODD_VTABLE: Vtable = Vtable { clone: promotable_odd_clone, + to_vec: promotable_odd_to_vec, drop: promotable_odd_drop, }; @@ -877,25 +936,57 @@ unsafe fn promotable_even_clone(data: &AtomicPtr<()>, ptr: *const u8, len: usize let kind = shared as usize & KIND_MASK; if kind == KIND_ARC { - shallow_clone_arc(shared as _, ptr, len) + shallow_clone_arc(shared.cast(), ptr, len) } else { debug_assert_eq!(kind, KIND_VEC); - let buf = (shared as usize & !KIND_MASK) as *mut u8; + let buf = ptr_map(shared.cast(), |addr| addr & !KIND_MASK); shallow_clone_vec(data, shared, buf, ptr, len) } } +unsafe fn promotable_to_vec( + data: &AtomicPtr<()>, + ptr: *const u8, + len: usize, + f: fn(*mut ()) -> *mut u8, +) -> Vec { + let shared = data.load(Ordering::Acquire); + let kind = shared as usize & KIND_MASK; + + if kind == KIND_ARC { + shared_to_vec_impl(shared.cast(), ptr, len) + } else { + // If Bytes holds a Vec, then the offset must be 0. + debug_assert_eq!(kind, KIND_VEC); + + let buf = f(shared); + + let cap = (ptr as usize - buf as usize) + len; + + // Copy back buffer + ptr::copy(ptr, buf, len); + + Vec::from_raw_parts(buf, len, cap) + } +} + +unsafe fn promotable_even_to_vec(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Vec { + promotable_to_vec(data, ptr, len, |shared| { + ptr_map(shared.cast(), |addr| addr & !KIND_MASK) + }) +} + unsafe fn promotable_even_drop(data: &mut AtomicPtr<()>, ptr: *const u8, len: usize) { data.with_mut(|shared| { let shared = *shared; let kind = shared as usize & KIND_MASK; if kind == KIND_ARC { - release_shared(shared as *mut Shared); + release_shared(shared.cast()); } else { debug_assert_eq!(kind, KIND_VEC); - let buf = (shared as usize & !KIND_MASK) as *mut u8; - drop(rebuild_boxed_slice(buf, ptr, len)); + let buf = ptr_map(shared.cast(), |addr| addr & !KIND_MASK); + free_boxed_slice(buf, ptr, len); } }); } @@ -908,38 +999,49 @@ unsafe fn promotable_odd_clone(data: &AtomicPtr<()>, ptr: *const u8, len: usize) shallow_clone_arc(shared as _, ptr, len) } else { debug_assert_eq!(kind, KIND_VEC); - shallow_clone_vec(data, shared, shared as *mut u8, ptr, len) + shallow_clone_vec(data, shared, shared.cast(), ptr, len) } } +unsafe fn promotable_odd_to_vec(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Vec { + promotable_to_vec(data, ptr, len, |shared| shared.cast()) +} + unsafe fn promotable_odd_drop(data: &mut AtomicPtr<()>, ptr: *const u8, len: usize) { data.with_mut(|shared| { let shared = *shared; let kind = shared as usize & KIND_MASK; if kind == KIND_ARC { - release_shared(shared as *mut Shared); + release_shared(shared.cast()); } else { debug_assert_eq!(kind, KIND_VEC); - drop(rebuild_boxed_slice(shared as *mut u8, ptr, len)); + free_boxed_slice(shared.cast(), ptr, len); } }); } -unsafe fn rebuild_boxed_slice(buf: *mut u8, offset: *const u8, len: usize) -> Box<[u8]> { +unsafe fn free_boxed_slice(buf: *mut u8, offset: *const u8, len: usize) { let cap = (offset as usize - buf as usize) + len; - Box::from_raw(slice::from_raw_parts_mut(buf, cap)) + dealloc(buf, Layout::from_size_align(cap, 1).unwrap()) } // ===== impl SharedVtable ===== struct Shared { - // holds vec for drop, but otherwise doesnt access it - _vec: Vec, + // Holds arguments to dealloc upon Drop, but otherwise doesn't use them + buf: *mut u8, + cap: usize, ref_cnt: AtomicUsize, } +impl Drop for Shared { + fn drop(&mut self) { + unsafe { dealloc(self.buf, Layout::from_size_align(self.cap, 1).unwrap()) } + } +} + // Assert that the alignment of `Shared` is divisible by 2. // This is a necessary invariant since we depend on allocating `Shared` a // shared object to implicitly carry the `KIND_ARC` flag in its pointer. @@ -948,6 +1050,7 @@ const _: [(); 0 - mem::align_of::() % 2] = []; // Assert that the alignm static SHARED_VTABLE: Vtable = Vtable { clone: shared_clone, + to_vec: shared_to_vec, drop: shared_drop, }; @@ -960,9 +1063,42 @@ unsafe fn shared_clone(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Byte shallow_clone_arc(shared as _, ptr, len) } +unsafe fn shared_to_vec_impl(shared: *mut Shared, ptr: *const u8, len: usize) -> Vec { + // Check that the ref_cnt is 1 (unique). + // + // If it is unique, then it is set to 0 with AcqRel fence for the same + // reason in release_shared. + // + // Otherwise, we take the other branch and call release_shared. + if (*shared) + .ref_cnt + .compare_exchange(1, 0, Ordering::AcqRel, Ordering::Relaxed) + .is_ok() + { + let buf = (*shared).buf; + let cap = (*shared).cap; + + // Deallocate Shared + drop(Box::from_raw(shared as *mut mem::ManuallyDrop)); + + // Copy back buffer + ptr::copy(ptr, buf, len); + + Vec::from_raw_parts(buf, len, cap) + } else { + let v = slice::from_raw_parts(ptr, len).to_vec(); + release_shared(shared); + v + } +} + +unsafe fn shared_to_vec(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Vec { + shared_to_vec_impl(data.load(Ordering::Relaxed).cast(), ptr, len) +} + unsafe fn shared_drop(data: &mut AtomicPtr<()>, _ptr: *const u8, _len: usize) { data.with_mut(|shared| { - release_shared(*shared as *mut Shared); + release_shared(shared.cast()); }); } @@ -1000,9 +1136,9 @@ unsafe fn shallow_clone_vec( // updated and since the buffer hasn't been promoted to an // `Arc`, those three fields still are the components of the // vector. - let vec = rebuild_boxed_slice(buf, offset, len).into_vec(); let shared = Box::new(Shared { - _vec: vec, + buf, + cap: (offset as usize - buf as usize) + len, // Initialize refcount to 2. One for this reference, and one // for the new clone that will be returned from // `shallow_clone`. @@ -1076,10 +1212,40 @@ unsafe fn release_shared(ptr: *mut Shared) { // > "acquire" operation before deleting the object. // // [1]: (www.boost.org/doc/libs/1_55_0/doc/html/atomic/usage_examples.html) - atomic::fence(Ordering::Acquire); + // + // Thread sanitizer does not support atomic fences. Use an atomic load + // instead. + (*ptr).ref_cnt.load(Ordering::Acquire); // Drop the data - Box::from_raw(ptr); + drop(Box::from_raw(ptr)); +} + +// Ideally we would always use this version of `ptr_map` since it is strict +// provenance compatible, but it results in worse codegen. We will however still +// use it on miri because it gives better diagnostics for people who test bytes +// code with miri. +// +// See https://github.com/tokio-rs/bytes/pull/545 for more info. +#[cfg(miri)] +fn ptr_map(ptr: *mut u8, f: F) -> *mut u8 +where + F: FnOnce(usize) -> usize, +{ + let old_addr = ptr as usize; + let new_addr = f(old_addr); + let diff = new_addr.wrapping_sub(old_addr); + ptr.wrapping_add(diff) +} + +#[cfg(not(miri))] +fn ptr_map(ptr: *mut u8, f: F) -> *mut u8 +where + F: FnOnce(usize) -> usize, +{ + let old_addr = ptr as usize; + let new_addr = f(old_addr); + new_addr as *mut u8 } // compile-fails diff --git a/src/bytes_mut.rs b/src/bytes_mut.rs index 8e42079e6..c5c2e52fc 100644 --- a/src/bytes_mut.rs +++ b/src/bytes_mut.rs @@ -1,5 +1,5 @@ use core::iter::{FromIterator, Iterator}; -use core::mem::{self, ManuallyDrop}; +use core::mem::{self, ManuallyDrop, MaybeUninit}; use core::ops::{Deref, DerefMut}; use core::ptr::{self, NonNull}; use core::{cmp, fmt, hash, isize, slice, usize}; @@ -8,6 +8,7 @@ use alloc::{ borrow::{Borrow, BorrowMut}, boxed::Box, string::String, + vec, vec::Vec, }; @@ -15,7 +16,7 @@ use crate::buf::{IntoIter, UninitSlice}; use crate::bytes::Vtable; #[allow(unused)] use crate::loom::sync::atomic::AtomicMut; -use crate::loom::sync::atomic::{self, AtomicPtr, AtomicUsize, Ordering}; +use crate::loom::sync::atomic::{AtomicPtr, AtomicUsize, Ordering}; use crate::{Buf, BufMut, Bytes}; /// A unique reference to a contiguous slice of memory. @@ -252,12 +253,28 @@ impl BytesMut { let ptr = self.ptr.as_ptr(); let len = self.len; - let data = AtomicPtr::new(self.data as _); + let data = AtomicPtr::new(self.data.cast()); mem::forget(self); unsafe { Bytes::with_vtable(ptr, len, data, &SHARED_VTABLE) } } } + /// Creates a new `BytesMut`, which is initialized with zero. + /// + /// # Examples + /// + /// ``` + /// use bytes::BytesMut; + /// + /// let zeros = BytesMut::zeroed(42); + /// + /// assert_eq!(zeros.len(), 42); + /// zeros.into_iter().for_each(|x| assert_eq!(x, 0)); + /// ``` + pub fn zeroed(len: usize) -> BytesMut { + BytesMut::from_vec(vec![0; len]) + } + /// Splits the bytes into two at the given index. /// /// Afterwards `self` contains elements `[0, at)`, and the returned @@ -380,6 +397,8 @@ impl BytesMut { /// If `len` is greater than the buffer's current length, this has no /// effect. /// + /// Existing underlying capacity is preserved. + /// /// The [`split_off`] method can emulate `truncate`, but this causes the /// excess bytes to be returned instead of dropped. /// @@ -402,7 +421,7 @@ impl BytesMut { } } - /// Clears the buffer, removing all data. + /// Clears the buffer, removing all data. Existing capacity is preserved. /// /// # Examples /// @@ -492,11 +511,20 @@ impl BytesMut { /// reallocations. A call to `reserve` may result in an allocation. /// /// Before allocating new buffer space, the function will attempt to reclaim - /// space in the existing buffer. If the current handle references a small - /// view in the original buffer and all other handles have been dropped, - /// and the requested capacity is less than or equal to the existing - /// buffer's capacity, then the current view will be copied to the front of - /// the buffer and the handle will take ownership of the full buffer. + /// space in the existing buffer. If the current handle references a view + /// into a larger original buffer, and all other handles referencing part + /// of the same original buffer have been dropped, then the current view + /// can be copied/shifted to the front of the buffer and the handle can take + /// ownership of the full buffer, provided that the full buffer is large + /// enough to fit the requested additional capacity. + /// + /// This optimization will only happen if shifting the data from the current + /// view to the front of the buffer is not too expensive in terms of the + /// (amortized) time required. The precise condition is subject to change; + /// as of now, the length of the data being shifted needs to be at least as + /// large as the distance that it's shifted by. If the current view is empty + /// and the original buffer is large enough to fit the requested additional + /// capacity, then reallocations will never happen. /// /// # Examples /// @@ -560,17 +588,34 @@ impl BytesMut { // space. // // Otherwise, since backed by a vector, use `Vec::reserve` + // + // We need to make sure that this optimization does not kill the + // amortized runtimes of BytesMut's operations. unsafe { let (off, prev) = self.get_vec_pos(); // Only reuse space if we can satisfy the requested additional space. - if self.capacity() - self.len() + off >= additional { - // There's space - reuse it + // + // Also check if the value of `off` suggests that enough bytes + // have been read to account for the overhead of shifting all + // the data (in an amortized analysis). + // Hence the condition `off >= self.len()`. + // + // This condition also already implies that the buffer is going + // to be (at least) half-empty in the end; so we do not break + // the (amortized) runtime with future resizes of the underlying + // `Vec`. + // + // [For more details check issue #524, and PR #525.] + if self.capacity() - self.len() + off >= additional && off >= self.len() { + // There's enough space, and it's not too much overhead: + // reuse the space! // // Just move the pointer back to the start after copying // data back. let base_ptr = self.ptr.as_ptr().offset(-(off as isize)); - ptr::copy(self.ptr.as_ptr(), base_ptr, self.len); + // Since `off >= self.len()`, the two regions don't overlap. + ptr::copy_nonoverlapping(self.ptr.as_ptr(), base_ptr, self.len); self.ptr = vptr(base_ptr); self.set_vec_pos(0, prev); @@ -578,13 +623,14 @@ impl BytesMut { // can gain capacity back. self.cap += off; } else { - // No space - allocate more + // Not enough space, or reusing might be too much overhead: + // allocate more space! let mut v = ManuallyDrop::new(rebuild_vec(self.ptr.as_ptr(), self.len, self.cap, off)); v.reserve(additional); // Update the info - self.ptr = vptr(v.as_mut_ptr().offset(off as isize)); + self.ptr = vptr(v.as_mut_ptr().add(off)); self.len = v.len() - off; self.cap = v.capacity() - off; } @@ -594,7 +640,7 @@ impl BytesMut { } debug_assert_eq!(kind, KIND_ARC); - let shared: *mut Shared = self.data as _; + let shared: *mut Shared = self.data; // Reserving involves abandoning the currently shared buffer and // allocating a new vector with the requested capacity. @@ -617,29 +663,65 @@ impl BytesMut { // sure that the vector has enough capacity. let v = &mut (*shared).vec; - if v.capacity() >= new_cap { - // The capacity is sufficient, reclaim the buffer - let ptr = v.as_mut_ptr(); + let v_capacity = v.capacity(); + let ptr = v.as_mut_ptr(); + + let offset = offset_from(self.ptr.as_ptr(), ptr); + + // Compare the condition in the `kind == KIND_VEC` case above + // for more details. + if v_capacity >= new_cap + offset { + self.cap = new_cap; + // no copy is necessary + } else if v_capacity >= new_cap && offset >= len { + // The capacity is sufficient, and copying is not too much + // overhead: reclaim the buffer! - ptr::copy(self.ptr.as_ptr(), ptr, len); + // `offset >= len` means: no overlap + ptr::copy_nonoverlapping(self.ptr.as_ptr(), ptr, len); self.ptr = vptr(ptr); self.cap = v.capacity(); + } else { + // calculate offset + let off = (self.ptr.as_ptr() as usize) - (v.as_ptr() as usize); - return; - } + // new_cap is calculated in terms of `BytesMut`, not the underlying + // `Vec`, so it does not take the offset into account. + // + // Thus we have to manually add it here. + new_cap = new_cap.checked_add(off).expect("overflow"); - // The vector capacity is not sufficient. The reserve request is - // asking for more than the initial buffer capacity. Allocate more - // than requested if `new_cap` is not much bigger than the current - // capacity. - // - // There are some situations, using `reserve_exact` that the - // buffer capacity could be below `original_capacity`, so do a - // check. - let double = v.capacity().checked_shl(1).unwrap_or(new_cap); + // The vector capacity is not sufficient. The reserve request is + // asking for more than the initial buffer capacity. Allocate more + // than requested if `new_cap` is not much bigger than the current + // capacity. + // + // There are some situations, using `reserve_exact` that the + // buffer capacity could be below `original_capacity`, so do a + // check. + let double = v.capacity().checked_shl(1).unwrap_or(new_cap); + + new_cap = cmp::max(double, new_cap); + + // No space - allocate more + // + // The length field of `Shared::vec` is not used by the `BytesMut`; + // instead we use the `len` field in the `BytesMut` itself. However, + // when calling `reserve`, it doesn't guarantee that data stored in + // the unused capacity of the vector is copied over to the new + // allocation, so we need to ensure that we don't have any data we + // care about in the unused capacity before calling `reserve`. + debug_assert!(off + len <= v.capacity()); + v.set_len(off + len); + v.reserve(new_cap - v.len()); - new_cap = cmp::max(cmp::max(double, new_cap), original_capacity); + // Update the info + self.ptr = vptr(v.as_mut_ptr().add(off)); + self.cap = v.capacity() - off; + } + + return; } else { new_cap = cmp::max(new_cap, original_capacity); } @@ -657,7 +739,7 @@ impl BytesMut { // Update self let data = (original_capacity_repr << ORIGINAL_CAPACITY_OFFSET) | KIND_VEC; - self.data = data as _; + self.data = invalid_ptr(data); self.ptr = vptr(v.as_mut_ptr()); self.len = v.len(); self.cap = v.capacity(); @@ -679,16 +761,17 @@ impl BytesMut { /// /// assert_eq!(b"aaabbbcccddd", &buf[..]); /// ``` + #[inline] pub fn extend_from_slice(&mut self, extend: &[u8]) { let cnt = extend.len(); self.reserve(cnt); unsafe { - let dst = self.uninit_slice(); + let dst = self.spare_capacity_mut(); // Reserved above debug_assert!(dst.len() >= cnt); - ptr::copy_nonoverlapping(extend.as_ptr(), dst.as_mut_ptr() as *mut u8, cnt); + ptr::copy_nonoverlapping(extend.as_ptr(), dst.as_mut_ptr().cast(), cnt); } unsafe { @@ -698,10 +781,11 @@ impl BytesMut { /// Absorbs a `BytesMut` that was previously split off. /// - /// If the two `BytesMut` objects were previously contiguous, i.e., if - /// `other` was created by calling `split_off` on this `BytesMut`, then - /// this is an `O(1)` operation that just decreases a reference - /// count and sets a few indices. Otherwise this method degenerates to + /// If the two `BytesMut` objects were previously contiguous and not mutated + /// in a way that causes re-allocation i.e., if `other` was created by + /// calling `split_off` on this `BytesMut`, then this is an `O(1)` operation + /// that just decreases a reference count and sets a few indices. + /// Otherwise this method degenerates to /// `self.extend_from_slice(other.as_ref())`. /// /// # Examples @@ -752,7 +836,7 @@ impl BytesMut { ptr, len, cap, - data: data as *mut _, + data: invalid_ptr(data), } } @@ -799,7 +883,7 @@ impl BytesMut { // Updating the start of the view is setting `ptr` to point to the // new start and updating the `len` field to reflect the new length // of the view. - self.ptr = vptr(self.ptr.as_ptr().offset(start as isize)); + self.ptr = vptr(self.ptr.as_ptr().add(start)); if self.len >= start { self.len -= start; @@ -823,7 +907,7 @@ impl BytesMut { return Ok(()); } - let ptr = unsafe { self.ptr.as_ptr().offset(self.len as isize) }; + let ptr = unsafe { self.ptr.as_ptr().add(self.len) }; if ptr == other.ptr.as_ptr() && self.kind() == KIND_ARC && other.kind() == KIND_ARC @@ -873,7 +957,7 @@ impl BytesMut { // always succeed. debug_assert_eq!(shared as usize & KIND_MASK, KIND_ARC); - self.data = shared as _; + self.data = shared; } /// Makes an exact shallow clone of `self`. @@ -906,16 +990,45 @@ impl BytesMut { debug_assert_eq!(self.kind(), KIND_VEC); debug_assert!(pos <= MAX_VEC_POS); - self.data = ((pos << VEC_POS_OFFSET) | (prev & NOT_VEC_POS_MASK)) as *mut _; + self.data = invalid_ptr((pos << VEC_POS_OFFSET) | (prev & NOT_VEC_POS_MASK)); } + /// Returns the remaining spare capacity of the buffer as a slice of `MaybeUninit`. + /// + /// The returned slice can be used to fill the buffer with data (e.g. by + /// reading from a file) before marking the data as initialized using the + /// [`set_len`] method. + /// + /// [`set_len`]: BytesMut::set_len + /// + /// # Examples + /// + /// ``` + /// use bytes::BytesMut; + /// + /// // Allocate buffer big enough for 10 bytes. + /// let mut buf = BytesMut::with_capacity(10); + /// + /// // Fill in the first 3 elements. + /// let uninit = buf.spare_capacity_mut(); + /// uninit[0].write(0); + /// uninit[1].write(1); + /// uninit[2].write(2); + /// + /// // Mark the first 3 bytes of the buffer as being initialized. + /// unsafe { + /// buf.set_len(3); + /// } + /// + /// assert_eq!(&buf[..], &[0, 1, 2]); + /// ``` #[inline] - fn uninit_slice(&mut self) -> &mut UninitSlice { + pub fn spare_capacity_mut(&mut self) -> &mut [MaybeUninit] { unsafe { - let ptr = self.ptr.as_ptr().offset(self.len as isize); + let ptr = self.ptr.as_ptr().add(self.len); let len = self.cap - self.len; - UninitSlice::from_raw_parts_mut(ptr, len) + slice::from_raw_parts_mut(ptr.cast(), len) } } } @@ -932,7 +1045,7 @@ impl Drop for BytesMut { let _ = rebuild_vec(self.ptr.as_ptr(), self.len, self.cap, off); } } else if kind == KIND_ARC { - unsafe { release_shared(self.data as _) }; + unsafe { release_shared(self.data) }; } } } @@ -989,7 +1102,7 @@ unsafe impl BufMut for BytesMut { if self.capacity() == self.len() { self.reserve(64); } - self.uninit_slice() + self.spare_capacity_mut().into() } // Specialize these methods so they can skip checking `remaining_mut` @@ -1010,6 +1123,19 @@ unsafe impl BufMut for BytesMut { fn put_slice(&mut self, src: &[u8]) { self.extend_from_slice(src); } + + fn put_bytes(&mut self, val: u8, cnt: usize) { + self.reserve(cnt); + unsafe { + let dst = self.spare_capacity_mut(); + // Reserved above + debug_assert!(dst.len() >= cnt); + + ptr::write_bytes(dst.as_mut_ptr(), val, cnt); + + self.advance_mut(cnt); + } + } } impl AsRef<[u8]> for BytesMut { @@ -1146,7 +1272,7 @@ impl<'a> IntoIterator for &'a BytesMut { type IntoIter = core::slice::Iter<'a, u8>; fn into_iter(self) -> Self::IntoIter { - self.as_ref().into_iter() + self.as_ref().iter() } } @@ -1175,7 +1301,18 @@ impl<'a> Extend<&'a u8> for BytesMut { where T: IntoIterator, { - self.extend(iter.into_iter().map(|b| *b)) + self.extend(iter.into_iter().copied()) + } +} + +impl Extend for BytesMut { + fn extend(&mut self, iter: T) + where + T: IntoIterator, + { + for bytes in iter { + self.extend_from_slice(&bytes) + } } } @@ -1187,7 +1324,7 @@ impl FromIterator for BytesMut { impl<'a> FromIterator<&'a u8> for BytesMut { fn from_iter>(into_iter: T) -> Self { - BytesMut::from_iter(into_iter.into_iter().map(|b| *b)) + BytesMut::from_iter(into_iter.into_iter().copied()) } } @@ -1228,10 +1365,13 @@ unsafe fn release_shared(ptr: *mut Shared) { // > "acquire" operation before deleting the object. // // [1]: (www.boost.org/doc/libs/1_55_0/doc/html/atomic/usage_examples.html) - atomic::fence(Ordering::Acquire); + // + // Thread sanitizer does not support atomic fences. Use an atomic load + // instead. + (*ptr).ref_count.load(Ordering::Acquire); // Drop the data - Box::from_raw(ptr); + drop(Box::from_raw(ptr)); } impl Shared { @@ -1377,7 +1517,7 @@ impl PartialOrd for str { impl PartialEq> for BytesMut { fn eq(&self, other: &Vec) -> bool { - *self == &other[..] + *self == other[..] } } @@ -1401,7 +1541,7 @@ impl PartialOrd for Vec { impl PartialEq for BytesMut { fn eq(&self, other: &String) -> bool { - *self == &other[..] + *self == other[..] } } @@ -1467,13 +1607,51 @@ impl PartialOrd for &str { impl PartialEq for Bytes { fn eq(&self, other: &BytesMut) -> bool { - &other[..] == &self[..] + other[..] == self[..] } } impl PartialEq for BytesMut { fn eq(&self, other: &Bytes) -> bool { - &other[..] == &self[..] + other[..] == self[..] + } +} + +impl From for Vec { + fn from(mut bytes: BytesMut) -> Self { + let kind = bytes.kind(); + + let mut vec = if kind == KIND_VEC { + unsafe { + let (off, _) = bytes.get_vec_pos(); + rebuild_vec(bytes.ptr.as_ptr(), bytes.len, bytes.cap, off) + } + } else if kind == KIND_ARC { + let shared = bytes.data as *mut Shared; + + if unsafe { (*shared).is_unique() } { + let vec = mem::replace(unsafe { &mut (*shared).vec }, Vec::new()); + + unsafe { release_shared(shared) }; + + vec + } else { + return bytes.deref().to_vec(); + } + } else { + return bytes.deref().to_vec(); + }; + + let len = bytes.len; + + unsafe { + ptr::copy(bytes.ptr.as_ptr(), vec.as_mut_ptr(), len); + vec.set_len(len); + } + + mem::forget(bytes); + + vec } } @@ -1486,6 +1664,35 @@ fn vptr(ptr: *mut u8) -> NonNull { } } +/// Returns a dangling pointer with the given address. This is used to store +/// integer data in pointer fields. +/// +/// It is equivalent to `addr as *mut T`, but this fails on miri when strict +/// provenance checking is enabled. +#[inline] +fn invalid_ptr(addr: usize) -> *mut T { + let ptr = core::ptr::null_mut::().wrapping_add(addr); + debug_assert_eq!(ptr as usize, addr); + ptr.cast::() +} + +/// Precondition: dst >= original +/// +/// The following line is equivalent to: +/// +/// ```rust,ignore +/// self.ptr.as_ptr().offset_from(ptr) as usize; +/// ``` +/// +/// But due to min rust is 1.39 and it is only stablised +/// in 1.47, we cannot use it. +#[inline] +fn offset_from(dst: *mut u8, original: *mut u8) -> usize { + debug_assert!(dst >= original); + + dst as usize - original as usize +} + unsafe fn rebuild_vec(ptr: *mut u8, mut len: usize, mut cap: usize, off: usize) -> Vec { let ptr = ptr.offset(-(off as isize)); len += off; @@ -1498,6 +1705,7 @@ unsafe fn rebuild_vec(ptr: *mut u8, mut len: usize, mut cap: usize, off: usize) static SHARED_VTABLE: Vtable = Vtable { clone: shared_v_clone, + to_vec: shared_v_to_vec, drop: shared_v_drop, }; @@ -1505,10 +1713,32 @@ unsafe fn shared_v_clone(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> By let shared = data.load(Ordering::Relaxed) as *mut Shared; increment_shared(shared); - let data = AtomicPtr::new(shared as _); + let data = AtomicPtr::new(shared as *mut ()); Bytes::with_vtable(ptr, len, data, &SHARED_VTABLE) } +unsafe fn shared_v_to_vec(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Vec { + let shared: *mut Shared = data.load(Ordering::Relaxed).cast(); + + if (*shared).is_unique() { + let shared = &mut *shared; + + // Drop shared + let mut vec = mem::replace(&mut shared.vec, Vec::new()); + release_shared(shared); + + // Copy back buffer + ptr::copy(ptr, vec.as_mut_ptr(), len); + vec.set_len(len); + + vec + } else { + let v = slice::from_raw_parts(ptr, len).to_vec(); + release_shared(shared); + v + } +} + unsafe fn shared_v_drop(data: &mut AtomicPtr<()>, _ptr: *const u8, _len: usize) { data.with_mut(|shared| { release_shared(*shared as *mut Shared); diff --git a/src/fmt/debug.rs b/src/fmt/debug.rs index a8545514e..83de695dd 100644 --- a/src/fmt/debug.rs +++ b/src/fmt/debug.rs @@ -25,7 +25,7 @@ impl Debug for BytesRef<'_> { } else if b == b'\0' { write!(f, "\\0")?; // ASCII printable - } else if b >= 0x20 && b < 0x7f { + } else if (0x20..0x7f).contains(&b) { write!(f, "{}", b as char)?; } else { write!(f, "\\x{:02x}", b)?; @@ -38,12 +38,12 @@ impl Debug for BytesRef<'_> { impl Debug for Bytes { fn fmt(&self, f: &mut Formatter<'_>) -> Result { - Debug::fmt(&BytesRef(&self.as_ref()), f) + Debug::fmt(&BytesRef(self.as_ref()), f) } } impl Debug for BytesMut { fn fmt(&self, f: &mut Formatter<'_>) -> Result { - Debug::fmt(&BytesRef(&self.as_ref()), f) + Debug::fmt(&BytesRef(self.as_ref()), f) } } diff --git a/src/lib.rs b/src/lib.rs index 5f6e5314b..d3e753055 100644 --- a/src/lib.rs +++ b/src/lib.rs @@ -4,6 +4,7 @@ attr(deny(warnings, rust_2018_idioms), allow(dead_code, unused_variables)) ))] #![no_std] +#![cfg_attr(docsrs, feature(doc_cfg))] //! Provides abstractions for working with bytes. //! diff --git a/src/loom.rs b/src/loom.rs index 09fc71e09..e30555c3d 100644 --- a/src/loom.rs +++ b/src/loom.rs @@ -4,7 +4,7 @@ pub(crate) mod sync { #[cfg(not(bytes_no_atomic_cas))] pub(crate) mod atomic { - pub(crate) use core::sync::atomic::{fence, AtomicPtr, AtomicUsize, Ordering}; + pub(crate) use core::sync::atomic::{AtomicPtr, AtomicUsize, Ordering}; pub(crate) trait AtomicMut { fn with_mut(&mut self, f: F) -> R @@ -26,7 +26,7 @@ pub(crate) mod sync { #[cfg(all(test, loom))] pub(crate) mod sync { pub(crate) mod atomic { - pub(crate) use loom::sync::atomic::{fence, AtomicPtr, AtomicUsize, Ordering}; + pub(crate) use loom::sync::atomic::{AtomicPtr, AtomicUsize, Ordering}; pub(crate) trait AtomicMut {} } diff --git a/tests/test_buf_mut.rs b/tests/test_buf_mut.rs index f63198226..865cccc33 100644 --- a/tests/test_buf_mut.rs +++ b/tests/test_buf_mut.rs @@ -3,6 +3,7 @@ use bytes::buf::UninitSlice; use bytes::{BufMut, BytesMut}; use core::fmt::Write; +use core::mem::MaybeUninit; use core::usize; #[test] @@ -27,6 +28,14 @@ fn test_vec_as_mut_buf() { assert_eq!(buf.len(), 68); } +#[test] +fn test_vec_put_bytes() { + let mut buf = Vec::new(); + buf.push(17); + buf.put_bytes(19, 2); + assert_eq!([17, 19, 19], &buf[..]); +} + #[test] fn test_put_u8() { let mut buf = Vec::with_capacity(8); @@ -45,6 +54,34 @@ fn test_put_u16() { assert_eq!(b"\x54\x21", &buf[..]); } +#[test] +fn test_put_int() { + let mut buf = Vec::with_capacity(8); + buf.put_int(0x1020304050607080, 3); + assert_eq!(b"\x60\x70\x80", &buf[..]); +} + +#[test] +#[should_panic] +fn test_put_int_nbytes_overflow() { + let mut buf = Vec::with_capacity(8); + buf.put_int(0x1020304050607080, 9); +} + +#[test] +fn test_put_int_le() { + let mut buf = Vec::with_capacity(8); + buf.put_int_le(0x1020304050607080, 3); + assert_eq!(b"\x80\x70\x60", &buf[..]); +} + +#[test] +#[should_panic] +fn test_put_int_le_nbytes_overflow() { + let mut buf = Vec::with_capacity(8); + buf.put_int_le(0x1020304050607080, 9); +} + #[test] #[should_panic(expected = "cannot advance")] fn test_vec_advance_mut() { @@ -65,14 +102,120 @@ fn test_clone() { assert!(buf != buf2); } +fn do_test_slice_small(make: impl Fn(&mut [u8]) -> &mut T) +where + for<'r> &'r mut T: BufMut, +{ + let mut buf = [b'X'; 8]; + + let mut slice = make(&mut buf[..]); + slice.put_bytes(b'A', 2); + slice.put_u8(b'B'); + slice.put_slice(b"BCC"); + assert_eq!(2, slice.remaining_mut()); + assert_eq!(b"AABBCCXX", &buf[..]); + + let mut slice = make(&mut buf[..]); + slice.put_u32(0x61626364); + assert_eq!(4, slice.remaining_mut()); + assert_eq!(b"abcdCCXX", &buf[..]); + + let mut slice = make(&mut buf[..]); + slice.put_u32_le(0x30313233); + assert_eq!(4, slice.remaining_mut()); + assert_eq!(b"3210CCXX", &buf[..]); +} + +fn do_test_slice_large(make: impl Fn(&mut [u8]) -> &mut T) +where + for<'r> &'r mut T: BufMut, +{ + const LEN: usize = 100; + const FILL: [u8; LEN] = [b'Y'; LEN]; + + let test = |fill: &dyn Fn(&mut &mut T, usize)| { + for buf_len in 0..LEN { + let mut buf = [b'X'; LEN]; + for fill_len in 0..=buf_len { + let mut slice = make(&mut buf[..buf_len]); + fill(&mut slice, fill_len); + assert_eq!(buf_len - fill_len, slice.remaining_mut()); + let (head, tail) = buf.split_at(fill_len); + assert_eq!(&FILL[..fill_len], head); + assert!(tail.iter().all(|b| *b == b'X')); + } + } + }; + + test(&|slice, fill_len| slice.put_slice(&FILL[..fill_len])); + test(&|slice, fill_len| slice.put_bytes(FILL[0], fill_len)); +} + +fn do_test_slice_put_slice_panics(make: impl Fn(&mut [u8]) -> &mut T) +where + for<'r> &'r mut T: BufMut, +{ + let mut buf = [b'X'; 4]; + let mut slice = make(&mut buf[..]); + slice.put_slice(b"12345"); +} + +fn do_test_slice_put_bytes_panics(make: impl Fn(&mut [u8]) -> &mut T) +where + for<'r> &'r mut T: BufMut, +{ + let mut buf = [b'X'; 4]; + let mut slice = make(&mut buf[..]); + slice.put_bytes(b'1', 5); +} + +#[test] +fn test_slice_buf_mut_small() { + do_test_slice_small(|x| x); +} + +#[test] +fn test_slice_buf_mut_large() { + do_test_slice_large(|x| x); +} + +#[test] +#[should_panic] +fn test_slice_buf_mut_put_slice_overflow() { + do_test_slice_put_slice_panics(|x| x); +} + +#[test] +#[should_panic] +fn test_slice_buf_mut_put_bytes_overflow() { + do_test_slice_put_bytes_panics(|x| x); +} + +fn make_maybe_uninit_slice(slice: &mut [u8]) -> &mut [MaybeUninit] { + // SAFETY: [u8] has the same layout as [MaybeUninit]. + unsafe { core::mem::transmute(slice) } +} + #[test] -fn test_mut_slice() { - let mut v = vec![0, 0, 0, 0]; - let mut s = &mut v[..]; - s.put_u32(42); +fn test_maybe_uninit_buf_mut_small() { + do_test_slice_small(make_maybe_uninit_slice); +} - assert_eq!(s.len(), 0); - assert_eq!(&v, &[0, 0, 0, 42]); +#[test] +fn test_maybe_uninit_buf_mut_large() { + do_test_slice_large(make_maybe_uninit_slice); +} + +#[test] +#[should_panic] +fn test_maybe_uninit_buf_mut_put_slice_overflow() { + do_test_slice_put_slice_panics(make_maybe_uninit_slice); +} + +#[test] +#[should_panic] +fn test_maybe_uninit_buf_mut_put_bytes_overflow() { + do_test_slice_put_bytes_panics(make_maybe_uninit_slice); } #[test] diff --git a/tests/test_bytes.rs b/tests/test_bytes.rs index 2d22fdddb..5ec60a5b0 100644 --- a/tests/test_bytes.rs +++ b/tests/test_bytes.rs @@ -4,8 +4,8 @@ use bytes::{Buf, BufMut, Bytes, BytesMut}; use std::usize; -const LONG: &'static [u8] = b"mary had a little lamb, little lamb, little lamb"; -const SHORT: &'static [u8] = b"hello world"; +const LONG: &[u8] = b"mary had a little lamb, little lamb, little lamb"; +const SHORT: &[u8] = b"hello world"; fn is_sync() {} fn is_send() {} @@ -411,8 +411,8 @@ fn freeze_after_split_off() { fn fns_defined_for_bytes_mut() { let mut bytes = BytesMut::from(&b"hello world"[..]); - bytes.as_ptr(); - bytes.as_mut_ptr(); + let _ = bytes.as_ptr(); + let _ = bytes.as_mut_ptr(); // Iterator let v: Vec = bytes.as_ref().iter().cloned().collect(); @@ -443,7 +443,7 @@ fn reserve_growth() { let _ = bytes.split(); bytes.reserve(65); - assert_eq!(bytes.capacity(), 128); + assert_eq!(bytes.capacity(), 117); } #[test] @@ -515,6 +515,34 @@ fn reserve_in_arc_unique_doubles() { assert_eq!(2000, bytes.capacity()); } +#[test] +fn reserve_in_arc_unique_does_not_overallocate_after_split() { + let mut bytes = BytesMut::from(LONG); + let orig_capacity = bytes.capacity(); + drop(bytes.split_off(LONG.len() / 2)); + + // now bytes is Arc and refcount == 1 + + let new_capacity = bytes.capacity(); + bytes.reserve(orig_capacity - new_capacity); + assert_eq!(bytes.capacity(), orig_capacity); +} + +#[test] +fn reserve_in_arc_unique_does_not_overallocate_after_multiple_splits() { + let mut bytes = BytesMut::from(LONG); + let orig_capacity = bytes.capacity(); + for _ in 0..10 { + drop(bytes.split_off(LONG.len() / 2)); + + // now bytes is Arc and refcount == 1 + + let new_capacity = bytes.capacity(); + bytes.reserve(orig_capacity - new_capacity); + } + assert_eq!(bytes.capacity(), orig_capacity); +} + #[test] fn reserve_in_arc_nonunique_does_not_overallocate() { let mut bytes = BytesMut::with_capacity(1000); @@ -527,6 +555,25 @@ fn reserve_in_arc_nonunique_does_not_overallocate() { assert_eq!(2001, bytes.capacity()); } +/// This function tests `BytesMut::reserve_inner`, where `BytesMut` holds +/// a unique reference to the shared vector and decide to reuse it +/// by reallocating the `Vec`. +#[test] +fn reserve_shared_reuse() { + let mut bytes = BytesMut::with_capacity(1000); + bytes.put_slice(b"Hello, World!"); + drop(bytes.split()); + + bytes.put_slice(b"!123ex123,sadchELLO,_wORLD!"); + // Use split_off so that v.capacity() - self.cap != off + drop(bytes.split_off(9)); + assert_eq!(&*bytes, b"!123ex123"); + + bytes.reserve(2000); + assert_eq!(&*bytes, b"!123ex123"); + assert_eq!(bytes.capacity(), 2009); +} + #[test] fn extend_mut() { let mut bytes = BytesMut::with_capacity(0); @@ -544,6 +591,13 @@ fn extend_from_slice_mut() { } } +#[test] +fn extend_mut_from_bytes() { + let mut bytes = BytesMut::with_capacity(0); + bytes.extend([Bytes::from(LONG)]); + assert_eq!(*bytes, LONG[..]); +} + #[test] fn extend_mut_without_size_hint() { let mut bytes = BytesMut::with_capacity(0); @@ -874,7 +928,7 @@ fn from_iter_no_size_hint() { fn test_slice_ref(bytes: &Bytes, start: usize, end: usize, expected: &[u8]) { let slice = &(bytes.as_ref()[start..end]); - let sub = bytes.slice_ref(&slice); + let sub = bytes.slice_ref(slice); assert_eq!(&sub[..], expected); } @@ -894,7 +948,7 @@ fn slice_ref_empty() { let bytes = Bytes::from(&b""[..]); let slice = &(bytes.as_ref()[0..0]); - let sub = bytes.slice_ref(&slice); + let sub = bytes.slice_ref(slice); assert_eq!(&sub[..], b""); } @@ -986,3 +1040,171 @@ fn bytes_with_capacity_but_empty() { let vec = Vec::with_capacity(1); let _ = Bytes::from(vec); } + +#[test] +fn bytes_put_bytes() { + let mut bytes = BytesMut::new(); + bytes.put_u8(17); + bytes.put_bytes(19, 2); + assert_eq!([17, 19, 19], bytes.as_ref()); +} + +#[test] +fn box_slice_empty() { + // See https://github.com/tokio-rs/bytes/issues/340 + let empty: Box<[u8]> = Default::default(); + let b = Bytes::from(empty); + assert!(b.is_empty()); +} + +#[test] +fn bytes_into_vec() { + // Test kind == KIND_VEC + let content = b"helloworld"; + + let mut bytes = BytesMut::new(); + bytes.put_slice(content); + + let vec: Vec = bytes.into(); + assert_eq!(&vec, content); + + // Test kind == KIND_ARC, shared.is_unique() == True + let mut bytes = BytesMut::new(); + bytes.put_slice(b"abcdewe23"); + bytes.put_slice(content); + + // Overwrite the bytes to make sure only one reference to the underlying + // Vec exists. + bytes = bytes.split_off(9); + + let vec: Vec = bytes.into(); + assert_eq!(&vec, content); + + // Test kind == KIND_ARC, shared.is_unique() == False + let prefix = b"abcdewe23"; + + let mut bytes = BytesMut::new(); + bytes.put_slice(prefix); + bytes.put_slice(content); + + let vec: Vec = bytes.split_off(prefix.len()).into(); + assert_eq!(&vec, content); + + let vec: Vec = bytes.into(); + assert_eq!(&vec, prefix); +} + +#[test] +fn test_bytes_into_vec() { + // Test STATIC_VTABLE.to_vec + let bs = b"1b23exfcz3r"; + let vec: Vec = Bytes::from_static(bs).into(); + assert_eq!(&*vec, bs); + + // Test bytes_mut.SHARED_VTABLE.to_vec impl + eprintln!("1"); + let mut bytes_mut: BytesMut = bs[..].into(); + + // Set kind to KIND_ARC so that after freeze, Bytes will use bytes_mut.SHARED_VTABLE + eprintln!("2"); + drop(bytes_mut.split_off(bs.len())); + + eprintln!("3"); + let b1 = bytes_mut.freeze(); + eprintln!("4"); + let b2 = b1.clone(); + + eprintln!("{:#?}", (&*b1).as_ptr()); + + // shared.is_unique() = False + eprintln!("5"); + assert_eq!(&*Vec::from(b2), bs); + + // shared.is_unique() = True + eprintln!("6"); + assert_eq!(&*Vec::from(b1), bs); + + // Test bytes_mut.SHARED_VTABLE.to_vec impl where offset != 0 + let mut bytes_mut1: BytesMut = bs[..].into(); + let bytes_mut2 = bytes_mut1.split_off(9); + + let b1 = bytes_mut1.freeze(); + let b2 = bytes_mut2.freeze(); + + assert_eq!(Vec::from(b2), bs[9..]); + assert_eq!(Vec::from(b1), bs[..9]); +} + +#[test] +fn test_bytes_into_vec_promotable_even() { + let vec = vec![33u8; 1024]; + + // Test cases where kind == KIND_VEC + let b1 = Bytes::from(vec.clone()); + assert_eq!(Vec::from(b1), vec); + + // Test cases where kind == KIND_ARC, ref_cnt == 1 + let b1 = Bytes::from(vec.clone()); + drop(b1.clone()); + assert_eq!(Vec::from(b1), vec); + + // Test cases where kind == KIND_ARC, ref_cnt == 2 + let b1 = Bytes::from(vec.clone()); + let b2 = b1.clone(); + assert_eq!(Vec::from(b1), vec); + + // Test cases where vtable = SHARED_VTABLE, kind == KIND_ARC, ref_cnt == 1 + assert_eq!(Vec::from(b2), vec); + + // Test cases where offset != 0 + let mut b1 = Bytes::from(vec.clone()); + let b2 = b1.split_off(20); + + assert_eq!(Vec::from(b2), vec[20..]); + assert_eq!(Vec::from(b1), vec[..20]); +} + +#[test] +fn test_bytes_vec_conversion() { + let mut vec = Vec::with_capacity(10); + vec.extend(b"abcdefg"); + let b = Bytes::from(vec); + let v = Vec::from(b); + assert_eq!(v.len(), 7); + assert_eq!(v.capacity(), 10); + + let mut b = Bytes::from(v); + b.advance(1); + let v = Vec::from(b); + assert_eq!(v.len(), 6); + assert_eq!(v.capacity(), 10); + assert_eq!(v.as_slice(), b"bcdefg"); +} + +#[test] +fn test_bytes_mut_conversion() { + let mut b1 = BytesMut::with_capacity(10); + b1.extend(b"abcdefg"); + let b2 = Bytes::from(b1); + let v = Vec::from(b2); + assert_eq!(v.len(), 7); + assert_eq!(v.capacity(), 10); + + let mut b = Bytes::from(v); + b.advance(1); + let v = Vec::from(b); + assert_eq!(v.len(), 6); + assert_eq!(v.capacity(), 10); + assert_eq!(v.as_slice(), b"bcdefg"); +} + +#[test] +fn test_bytes_capacity_len() { + for cap in 0..100 { + for len in 0..=cap { + let mut v = Vec::with_capacity(cap); + v.resize(len, 0); + let _ = Bytes::from(v); + } + } +} diff --git a/tests/test_bytes_odd_alloc.rs b/tests/test_bytes_odd_alloc.rs index 04ba7c2f1..27ed87736 100644 --- a/tests/test_bytes_odd_alloc.rs +++ b/tests/test_bytes_odd_alloc.rs @@ -24,8 +24,7 @@ unsafe impl GlobalAlloc for Odd { }; let ptr = System.alloc(new_layout); if !ptr.is_null() { - let ptr = ptr.offset(1); - ptr + ptr.offset(1) } else { ptr } @@ -67,3 +66,32 @@ fn test_bytes_clone_drop() { let b1 = Bytes::from(vec); let _b2 = b1.clone(); } + +#[test] +fn test_bytes_into_vec() { + let vec = vec![33u8; 1024]; + + // Test cases where kind == KIND_VEC + let b1 = Bytes::from(vec.clone()); + assert_eq!(Vec::from(b1), vec); + + // Test cases where kind == KIND_ARC, ref_cnt == 1 + let b1 = Bytes::from(vec.clone()); + drop(b1.clone()); + assert_eq!(Vec::from(b1), vec); + + // Test cases where kind == KIND_ARC, ref_cnt == 2 + let b1 = Bytes::from(vec.clone()); + let b2 = b1.clone(); + assert_eq!(Vec::from(b1), vec); + + // Test cases where vtable = SHARED_VTABLE, kind == KIND_ARC, ref_cnt == 1 + assert_eq!(Vec::from(b2), vec); + + // Test cases where offset != 0 + let mut b1 = Bytes::from(vec.clone()); + let b2 = b1.split_off(20); + + assert_eq!(Vec::from(b2), vec[20..]); + assert_eq!(Vec::from(b1), vec[..20]); +} diff --git a/tests/test_bytes_vec_alloc.rs b/tests/test_bytes_vec_alloc.rs index 418a9cd64..107e56e58 100644 --- a/tests/test_bytes_vec_alloc.rs +++ b/tests/test_bytes_vec_alloc.rs @@ -1,61 +1,87 @@ use std::alloc::{GlobalAlloc, Layout, System}; -use std::{mem, ptr}; +use std::ptr::null_mut; +use std::sync::atomic::{AtomicPtr, AtomicUsize, Ordering}; use bytes::{Buf, Bytes}; #[global_allocator] -static LEDGER: Ledger = Ledger; +static LEDGER: Ledger = Ledger::new(); -struct Ledger; +const LEDGER_LENGTH: usize = 2048; -const USIZE_SIZE: usize = mem::size_of::(); +struct Ledger { + alloc_table: [(AtomicPtr, AtomicUsize); LEDGER_LENGTH], +} -unsafe impl GlobalAlloc for Ledger { - unsafe fn alloc(&self, layout: Layout) -> *mut u8 { - if layout.align() == 1 && layout.size() > 0 { - // Allocate extra space to stash a record of - // how much space there was. - let orig_size = layout.size(); - let size = orig_size + USIZE_SIZE; - let new_layout = match Layout::from_size_align(size, 1) { - Ok(layout) => layout, - Err(_err) => return ptr::null_mut(), - }; - let ptr = System.alloc(new_layout); - if !ptr.is_null() { - (ptr as *mut usize).write(orig_size); - let ptr = ptr.offset(USIZE_SIZE as isize); - ptr - } else { - ptr +impl Ledger { + const fn new() -> Self { + const ELEM: (AtomicPtr, AtomicUsize) = + (AtomicPtr::new(null_mut()), AtomicUsize::new(0)); + let alloc_table = [ELEM; LEDGER_LENGTH]; + + Self { alloc_table } + } + + /// Iterate over our table until we find an open entry, then insert into said entry + fn insert(&self, ptr: *mut u8, size: usize) { + for (entry_ptr, entry_size) in self.alloc_table.iter() { + // SeqCst is good enough here, we don't care about perf, i just want to be correct! + if entry_ptr + .compare_exchange(null_mut(), ptr, Ordering::SeqCst, Ordering::SeqCst) + .is_ok() + { + entry_size.store(size, Ordering::SeqCst); + break; } - } else { - System.alloc(layout) } } - unsafe fn dealloc(&self, ptr: *mut u8, layout: Layout) { - if layout.align() == 1 && layout.size() > 0 { - let off_ptr = (ptr as *mut usize).offset(-1); - let orig_size = off_ptr.read(); - if orig_size != layout.size() { - panic!( - "bad dealloc: alloc size was {}, dealloc size is {}", - orig_size, - layout.size() - ); + fn remove(&self, ptr: *mut u8) -> usize { + for (entry_ptr, entry_size) in self.alloc_table.iter() { + // set the value to be something that will never try and be deallocated, so that we + // don't have any chance of a race condition + // + // dont worry, LEDGER_LENGTH is really long to compensate for us not reclaiming space + if entry_ptr + .compare_exchange( + ptr, + invalid_ptr(usize::MAX), + Ordering::SeqCst, + Ordering::SeqCst, + ) + .is_ok() + { + return entry_size.load(Ordering::SeqCst); } + } + + panic!("Couldn't find a matching entry for {:x?}", ptr); + } +} + +unsafe impl GlobalAlloc for Ledger { + unsafe fn alloc(&self, layout: Layout) -> *mut u8 { + let size = layout.size(); + let ptr = System.alloc(layout); + self.insert(ptr, size); + ptr + } + + unsafe fn dealloc(&self, ptr: *mut u8, layout: Layout) { + let orig_size = self.remove(ptr); - let new_layout = match Layout::from_size_align(layout.size() + USIZE_SIZE, 1) { - Ok(layout) => layout, - Err(_err) => std::process::abort(), - }; - System.dealloc(off_ptr as *mut u8, new_layout); + if orig_size != layout.size() { + panic!( + "bad dealloc: alloc size was {}, dealloc size is {}", + orig_size, + layout.size() + ); } else { System.dealloc(ptr, layout); } } } + #[test] fn test_bytes_advance() { let mut bytes = Bytes::from(vec![10, 20, 30]); @@ -77,3 +103,41 @@ fn test_bytes_truncate_and_advance() { bytes.advance(1); drop(bytes); } + +/// Returns a dangling pointer with the given address. This is used to store +/// integer data in pointer fields. +#[inline] +fn invalid_ptr(addr: usize) -> *mut T { + let ptr = std::ptr::null_mut::().wrapping_add(addr); + debug_assert_eq!(ptr as usize, addr); + ptr.cast::() +} + +#[test] +fn test_bytes_into_vec() { + let vec = vec![33u8; 1024]; + + // Test cases where kind == KIND_VEC + let b1 = Bytes::from(vec.clone()); + assert_eq!(Vec::from(b1), vec); + + // Test cases where kind == KIND_ARC, ref_cnt == 1 + let b1 = Bytes::from(vec.clone()); + drop(b1.clone()); + assert_eq!(Vec::from(b1), vec); + + // Test cases where kind == KIND_ARC, ref_cnt == 2 + let b1 = Bytes::from(vec.clone()); + let b2 = b1.clone(); + assert_eq!(Vec::from(b1), vec); + + // Test cases where vtable = SHARED_VTABLE, kind == KIND_ARC, ref_cnt == 1 + assert_eq!(Vec::from(b2), vec); + + // Test cases where offset != 0 + let mut b1 = Bytes::from(vec.clone()); + let b2 = b1.split_off(20); + + assert_eq!(Vec::from(b2), vec[20..]); + assert_eq!(Vec::from(b1), vec[..20]); +} diff --git a/tests/test_chain.rs b/tests/test_chain.rs index affaf7a9e..cfda6b8dc 100644 --- a/tests/test_chain.rs +++ b/tests/test_chain.rs @@ -133,6 +133,28 @@ fn vectored_read() { } } +#[test] +fn chain_growing_buffer() { + let mut buff = [' ' as u8; 10]; + let mut vec = b"wassup".to_vec(); + + let mut chained = (&mut buff[..]).chain_mut(&mut vec).chain_mut(Vec::new()); // Required for potential overflow because remaining_mut for Vec is isize::MAX - vec.len(), but for chain_mut is usize::MAX + + chained.put_slice(b"hey there123123"); + + assert_eq!(&buff, b"hey there1"); + assert_eq!(&vec, b"wassup23123"); +} + +#[test] +fn chain_overflow_remaining_mut() { + let mut chained = Vec::::new().chain_mut(Vec::new()).chain_mut(Vec::new()); + + assert_eq!(chained.remaining_mut(), usize::MAX); + chained.put_slice(&[0; 256]); + assert_eq!(chained.remaining_mut(), usize::MAX); +} + #[test] fn chain_get_bytes() { let mut ab = Bytes::copy_from_slice(b"ab");