From 0c86f2ba22885e84eee74e148362cec4f7f1fb88 Mon Sep 17 00:00:00 2001 From: DongHun Kwak Date: Wed, 8 Mar 2023 09:11:17 +0900 Subject: [PATCH] Import bytes 1.4.0 --- .cargo_vcs_info.json | 6 + .github/workflows/ci.yml | 172 ++++ .gitignore | 2 + CHANGELOG.md | 283 +++++++ Cargo.toml | 54 ++ Cargo.toml.orig | 34 + LICENSE | 25 + README.md | 56 ++ benches/buf.rs | 186 +++++ benches/bytes.rs | 120 +++ benches/bytes_mut.rs | 266 ++++++ ci/miri.sh | 11 + ci/test-stable.sh | 28 + ci/tsan.sh | 13 + clippy.toml | 1 + src/buf/buf_impl.rs | 1394 +++++++++++++++++++++++++++++++ src/buf/buf_mut.rs | 1493 +++++++++++++++++++++++++++++++++ src/buf/chain.rs | 242 ++++++ src/buf/iter.rs | 130 +++ src/buf/limit.rs | 75 ++ src/buf/mod.rs | 41 + src/buf/reader.rs | 81 ++ src/buf/take.rs | 155 ++++ src/buf/uninit_slice.rs | 213 +++++ src/buf/vec_deque.rs | 22 + src/buf/writer.rs | 88 ++ src/bytes.rs | 1304 +++++++++++++++++++++++++++++ src/bytes_mut.rs | 1812 +++++++++++++++++++++++++++++++++++++++++ src/fmt/debug.rs | 49 ++ src/fmt/hex.rs | 37 + src/fmt/mod.rs | 5 + src/lib.rs | 117 +++ src/loom.rs | 30 + src/serde.rs | 89 ++ tests/test_buf.rs | 120 +++ tests/test_buf_mut.rs | 178 ++++ tests/test_bytes.rs | 1210 +++++++++++++++++++++++++++ tests/test_bytes_odd_alloc.rs | 97 +++ tests/test_bytes_vec_alloc.rs | 143 ++++ tests/test_chain.rs | 177 ++++ tests/test_debug.rs | 35 + tests/test_iter.rs | 21 + tests/test_reader.rs | 29 + tests/test_serde.rs | 20 + tests/test_take.rs | 32 + 45 files changed, 10696 insertions(+) create mode 100644 .cargo_vcs_info.json create mode 100644 .github/workflows/ci.yml create mode 100644 .gitignore create mode 100644 CHANGELOG.md create mode 100644 Cargo.toml create mode 100644 Cargo.toml.orig create mode 100644 LICENSE create mode 100644 README.md create mode 100644 benches/buf.rs create mode 100644 benches/bytes.rs create mode 100644 benches/bytes_mut.rs create mode 100755 ci/miri.sh create mode 100644 ci/test-stable.sh create mode 100644 ci/tsan.sh create mode 100644 clippy.toml create mode 100644 src/buf/buf_impl.rs create mode 100644 src/buf/buf_mut.rs create mode 100644 src/buf/chain.rs create mode 100644 src/buf/iter.rs create mode 100644 src/buf/limit.rs create mode 100644 src/buf/mod.rs create mode 100644 src/buf/reader.rs create mode 100644 src/buf/take.rs create mode 100644 src/buf/uninit_slice.rs create mode 100644 src/buf/vec_deque.rs create mode 100644 src/buf/writer.rs create mode 100644 src/bytes.rs create mode 100644 src/bytes_mut.rs create mode 100644 src/fmt/debug.rs create mode 100644 src/fmt/hex.rs create mode 100644 src/fmt/mod.rs create mode 100644 src/lib.rs create mode 100644 src/loom.rs create mode 100644 src/serde.rs create mode 100644 tests/test_buf.rs create mode 100644 tests/test_buf_mut.rs create mode 100644 tests/test_bytes.rs create mode 100644 tests/test_bytes_odd_alloc.rs create mode 100644 tests/test_bytes_vec_alloc.rs create mode 100644 tests/test_chain.rs create mode 100644 tests/test_debug.rs create mode 100644 tests/test_iter.rs create mode 100644 tests/test_reader.rs create mode 100644 tests/test_serde.rs create mode 100644 tests/test_take.rs diff --git a/.cargo_vcs_info.json b/.cargo_vcs_info.json new file mode 100644 index 0000000..b4c4c4e --- /dev/null +++ b/.cargo_vcs_info.json @@ -0,0 +1,6 @@ +{ + "git": { + "sha1": "21ed3328364716fa30a4bf7502c913bbf0a90f45" + }, + "path_in_vcs": "" +} \ No newline at end of file diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml new file mode 100644 index 0000000..a4f7b1d --- /dev/null +++ b/.github/workflows/ci.yml @@ -0,0 +1,172 @@ +name: CI + +on: + pull_request: + branches: + - master + push: + branches: + - master + +env: + RUSTFLAGS: -Dwarnings + RUST_BACKTRACE: 1 + nightly: nightly-2022-11-12 + +defaults: + run: + shell: bash + +jobs: + # Check formatting + rustfmt: + name: rustfmt + runs-on: ubuntu-latest + steps: + - uses: actions/checkout@v3 + - name: Install Rust + run: rustup update stable && rustup default stable + - name: Check formatting + run: cargo fmt --all -- --check + + # TODO + # # Apply clippy lints + # clippy: + # name: clippy + # runs-on: ubuntu-latest + # steps: + # - uses: actions/checkout@v3 + # - name: Apply clippy lints + # run: cargo clippy --all-features + + # This represents the minimum Rust version supported by + # Bytes. Updating this should be done in a dedicated PR. + # + # Tests are not run as tests may require newer versions of + # rust. + minrust: + name: minrust + runs-on: ubuntu-latest + steps: + - uses: actions/checkout@v3 + - name: Install Rust + run: rustup update 1.39.0 && rustup default 1.39.0 + - name: Check + run: . ci/test-stable.sh check + + # Stable + stable: + name: stable + strategy: + matrix: + os: + - ubuntu-latest + - macos-latest + - windows-latest + runs-on: ${{ matrix.os }} + steps: + - 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 && rustup default stable + - name: Test + run: . ci/test-stable.sh test + + # Nightly + nightly: + name: nightly + runs-on: ubuntu-latest + steps: + - uses: actions/checkout@v3 + - name: Install Rust + run: rustup update $nightly && rustup default $nightly + - name: Test + run: . ci/test-stable.sh test + + # Run tests on some extra platforms + cross: + name: cross + strategy: + matrix: + target: + - i686-unknown-linux-gnu + - armv7-unknown-linux-gnueabihf + - powerpc-unknown-linux-gnu + - powerpc64-unknown-linux-gnu + - wasm32-unknown-unknown + runs-on: ubuntu-latest + steps: + - uses: actions/checkout@v3 + - name: Install Rust + run: rustup update stable && rustup default stable + - name: cross build --target ${{ matrix.target }} + run: | + cargo install cross + cross build --target ${{ matrix.target }} + if: matrix.target != 'wasm32-unknown-unknown' + # WASM support + - name: cargo build --target ${{ matrix.target }} + run: | + rustup target add ${{ matrix.target }} + cargo build --target ${{ matrix.target }} + if: matrix.target == 'wasm32-unknown-unknown' + + # Sanitizers + tsan: + name: tsan + runs-on: ubuntu-latest + steps: + - uses: actions/checkout@v3 + - name: Install Rust + run: rustup update $nightly && rustup default $nightly + - name: Install rust-src + run: rustup component add rust-src + - name: ASAN / TSAN + run: . ci/tsan.sh + miri: + name: miri + runs-on: ubuntu-latest + steps: + - uses: actions/checkout@v3 + - name: Miri + run: ci/miri.sh + + # Loom + loom: + name: loom + runs-on: ubuntu-latest + steps: + - uses: actions/checkout@v3 + - name: Install Rust + run: rustup update $nightly && rustup default $nightly + - name: Loom tests + run: RUSTFLAGS="--cfg loom -Dwarnings" cargo test --lib + + publish_docs: + name: Publish Documentation + needs: + - rustfmt + # - clippy + - stable + - nightly + - minrust + - cross + - tsan + - loom + runs-on: ubuntu-latest + steps: + - uses: actions/checkout@v3 + - name: Install Rust + run: rustup update $nightly && rustup default $nightly + - name: Build documentation + run: cargo doc --no-deps --all-features + env: + RUSTDOCFLAGS: --cfg docsrs + - name: Publish documentation + run: | + cd target/doc + git init + git add . + git -c user.name='ci' -c user.email='ci' commit -m 'Deploy Bytes API documentation' + git push -f -q https://git:${{ secrets.github_token }}@github.com/${{ github.repository }} HEAD:gh-pages + if: github.event_name == 'push' && github.event.ref == 'refs/heads/master' && github.repository == 'tokio-rs/bytes' diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..4fffb2f --- /dev/null +++ b/.gitignore @@ -0,0 +1,2 @@ +/target +/Cargo.lock diff --git a/CHANGELOG.md b/CHANGELOG.md new file mode 100644 index 0000000..a1bad4a --- /dev/null +++ b/CHANGELOG.md @@ -0,0 +1,283 @@ +# 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 +- mark `Vec::put_slice` with `#[inline]` (#459) + +### Fixed +- Fix deprecation warning (#457) +- use `Box::into_raw` instead of `mem::forget`-in-disguise (#458) + +# 1.0.0 (December 22, 2020) + +### Changed +- Rename `Buf`/`BufMut` methods `bytes()` and `bytes_mut()` to `chunk()` and `chunk_mut()` (#450) + +### Removed +- remove unused Buf implementation. (#449) + +# 0.6.0 (October 21, 2020) + +API polish in preparation for a 1.0 release. + +### Changed +- `BufMut` is now an `unsafe` trait (#432). +- `BufMut::bytes_mut()` returns `&mut UninitSlice`, a type owned by `bytes` to + avoid undefined behavior (#433). +- `Buf::copy_to_bytes(len)` replaces `Buf::into_bytes()` (#439). +- `Buf`/`BufMut` utility methods are moved onto the trait and `*Ext` traits are + removed (#431). + +### Removed +- `BufMut::bytes_vectored_mut()` (#430). +- `new` methods on combinator types (#434). + +# 0.5.6 (July 13, 2020) + +- Improve `BytesMut` to reuse buffer when fully `advance`d. +- Mark `BytesMut::{as_mut, set_len}` with `#[inline]`. +- Relax synchronization when cloning in shared vtable of `Bytes`. +- Move `loom` to `dev-dependencies`. + +# 0.5.5 (June 18, 2020) + +### Added +- Allow using the `serde` feature in `no_std` environments (#385). + +### Fix +- Fix `BufMut::advance_mut` to panic if advanced passed the capacity (#354).. +- Fix `BytesMut::freeze` ignoring amount previously `advance`d (#352). + +# 0.5.4 (January 23, 2020) + +### Added +- Make `Bytes::new` a `const fn`. +- Add `From` for `Bytes`. + +### Fix +- Fix reversed arguments in `PartialOrd` for `Bytes`. +- Fix `Bytes::truncate` losing original capacity when repr is an unshared `Vec`. +- Fix `Bytes::from(Vec)` when allocator gave `Vec` a pointer with LSB set. +- Fix panic in `Bytes::slice_ref` if argument is an empty slice. + +# 0.5.3 (December 12, 2019) + +### Added +- `must_use` attributes to `split`, `split_off`, and `split_to` methods (#337). + +### Fix +- Potential freeing of a null pointer in `Bytes` when constructed with an empty `Vec` (#341, #342). +- Calling `Bytes::truncate` with a size large than the length will no longer clear the `Bytes` (#333). + +# 0.5.2 (November 27, 2019) + +### Added +- `Limit` methods `into_inner`, `get_ref`, `get_mut`, `limit`, and `set_limit` (#325). + +# 0.5.1 (November 25, 2019) + +### Fix +- Growth documentation for `BytesMut` (#321) + +# 0.5.0 (November 25, 2019) + +### Fix +- Potential overflow in `copy_to_slice` + +### Changed +- Increased minimum supported Rust version to 1.39. +- `Bytes` is now a "trait object", allowing for custom allocation strategies (#298) +- `BytesMut` implicitly grows internal storage. `remaining_mut()` returns + `usize::MAX` (#316). +- `BufMut::bytes_mut` returns `&mut [MaybeUninit]` to reflect the unknown + initialization state (#305). +- `Buf` / `BufMut` implementations for `&[u8]` and `&mut [u8]` + respectively (#261). +- Move `Buf` / `BufMut` "extra" functions to an extension trait (#306). +- `BufMutExt::limit` (#309). +- `Bytes::slice` takes a `RangeBounds` argument (#265). +- `Bytes::from_static` is now a `const fn` (#311). +- A multitude of smaller performance optimizations. + +### Added +- `no_std` support (#281). +- `get_*`, `put_*`, `get_*_le`, and `put_*le` accessors for handling byte order. +- `BorrowMut` implementation for `BytesMut` (#185). + +### Removed +- `IntoBuf` (#288). +- `Buf` implementation for `&str` (#301). +- `byteorder` dependency (#280). +- `iovec` dependency, use `std::IoSlice` instead (#263). +- optional `either` dependency (#315). +- optional `i128` feature -- now available on stable. (#276). + +# 0.4.12 (March 6, 2019) + +### Added +- Implement `FromIterator<&'a u8>` for `BytesMut`/`Bytes` (#244). +- Implement `Buf` for `VecDeque` (#249). + +# 0.4.11 (November 17, 2018) + +* Use raw pointers for potentially racy loads (#233). +* Implement `BufRead` for `buf::Reader` (#232). +* Documentation tweaks (#234). + +# 0.4.10 (September 4, 2018) + +* impl `Buf` and `BufMut` for `Either` (#225). +* Add `Bytes::slice_ref` (#208). + +# 0.4.9 (July 12, 2018) + +* Add 128 bit number support behind a feature flag (#209). +* Implement `IntoBuf` for `&mut [u8]` + +# 0.4.8 (May 25, 2018) + +* Fix panic in `BytesMut` `FromIterator` implementation. +* Bytes: Recycle space when reserving space in vec mode (#197). +* Bytes: Add resize fn (#203). + +# 0.4.7 (April 27, 2018) + +* Make `Buf` and `BufMut` usable as trait objects (#186). +* impl BorrowMut for BytesMut (#185). +* Improve accessor performance (#195). + +# 0.4.6 (Janary 8, 2018) + +* Implement FromIterator for Bytes/BytesMut (#148). +* Add `advance` fn to Bytes/BytesMut (#166). +* Add `unsplit` fn to `BytesMut` (#162, #173). +* Improvements to Bytes split fns (#92). + +# 0.4.5 (August 12, 2017) + +* Fix range bug in `Take::bytes` +* Misc performance improvements +* Add extra `PartialEq` implementations. +* Add `Bytes::with_capacity` +* Implement `AsMut[u8]` for `BytesMut` + +# 0.4.4 (May 26, 2017) + +* Add serde support behind feature flag +* Add `extend_from_slice` on `Bytes` and `BytesMut` +* Add `truncate` and `clear` on `Bytes` +* Misc additional std trait implementations +* Misc performance improvements + +# 0.4.3 (April 30, 2017) + +* Fix Vec::advance_mut bug +* Bump minimum Rust version to 1.15 +* Misc performance tweaks + +# 0.4.2 (April 5, 2017) + +* Misc performance tweaks +* Improved `Debug` implementation for `Bytes` +* Avoid some incorrect assert panics + +# 0.4.1 (March 15, 2017) + +* Expose `buf` module and have most types available from there vs. root. +* Implement `IntoBuf` for `T: Buf`. +* Add `FromBuf` and `Buf::collect`. +* Add iterator adapter for `Buf`. +* Add scatter/gather support to `Buf` and `BufMut`. +* Add `Buf::chain`. +* Reduce allocations on repeated calls to `BytesMut::reserve`. +* Implement `Debug` for more types. +* Remove `Source` in favor of `IntoBuf`. +* Implement `Extend` for `BytesMut`. + + +# 0.4.0 (February 24, 2017) + +* Initial release diff --git a/Cargo.toml b/Cargo.toml new file mode 100644 index 0000000..d0acb34 --- /dev/null +++ b/Cargo.toml @@ -0,0 +1,54 @@ +# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO +# +# When uploading crates to the registry Cargo will automatically +# "normalize" Cargo.toml files for maximal compatibility +# with all versions of Cargo and also rewrite `path` dependencies +# to registry (e.g., crates.io) dependencies. +# +# If you are reading this file be aware that the original Cargo.toml +# will likely look very different (and much more reasonable). +# See Cargo.toml.orig for the original contents. + +[package] +edition = "2018" +name = "bytes" +version = "1.4.0" +authors = [ + "Carl Lerche ", + "Sean McArthur ", +] +description = "Types and traits for working with bytes" +readme = "README.md" +keywords = [ + "buffers", + "zero-copy", + "io", +] +categories = [ + "network-programming", + "data-structures", +] +license = "MIT" +repository = "https://github.com/tokio-rs/bytes" + +[package.metadata.docs.rs] +rustdoc-args = [ + "--cfg", + "docsrs", +] + +[dependencies.serde] +version = "1.0.60" +features = ["alloc"] +optional = true +default-features = false + +[dev-dependencies.serde_test] +version = "1.0" + +[features] +default = ["std"] +std = [] + +[target."cfg(loom)".dev-dependencies.loom] +version = "0.5" diff --git a/Cargo.toml.orig b/Cargo.toml.orig new file mode 100644 index 0000000..4a96ec1 --- /dev/null +++ b/Cargo.toml.orig @@ -0,0 +1,34 @@ +[package] + +name = "bytes" +# When releasing to crates.io: +# - Update CHANGELOG.md. +# - Create "v1.x.y" git tag. +version = "1.4.0" +license = "MIT" +authors = [ + "Carl Lerche ", + "Sean McArthur ", +] +description = "Types and traits for working with bytes" +repository = "https://github.com/tokio-rs/bytes" +readme = "README.md" +keywords = ["buffers", "zero-copy", "io"] +categories = ["network-programming", "data-structures"] +edition = "2018" + +[features] +default = ["std"] +std = [] + +[dependencies] +serde = { version = "1.0.60", optional = true, default-features = false, features = ["alloc"] } + +[dev-dependencies] +serde_test = "1.0" + +[target.'cfg(loom)'.dev-dependencies] +loom = "0.5" + +[package.metadata.docs.rs] +rustdoc-args = ["--cfg", "docsrs"] diff --git a/LICENSE b/LICENSE new file mode 100644 index 0000000..58fb29a --- /dev/null +++ b/LICENSE @@ -0,0 +1,25 @@ +Copyright (c) 2018 Carl Lerche + +Permission is hereby granted, free of charge, to any +person obtaining a copy of this software and associated +documentation files (the "Software"), to deal in the +Software without restriction, including without +limitation the rights to use, copy, modify, merge, +publish, distribute, sublicense, and/or sell copies of +the Software, and to permit persons to whom the Software +is furnished to do so, subject to the following +conditions: + +The above copyright notice and this permission notice +shall be included in all copies or substantial portions +of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF +ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED +TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A +PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT +SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY +CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION +OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR +IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER +DEALINGS IN THE SOFTWARE. diff --git a/README.md b/README.md new file mode 100644 index 0000000..be46642 --- /dev/null +++ b/README.md @@ -0,0 +1,56 @@ +# Bytes + +A utility library for working with bytes. + +[![Crates.io][crates-badge]][crates-url] +[![Build Status][ci-badge]][ci-url] + +[crates-badge]: https://img.shields.io/crates/v/bytes.svg +[crates-url]: https://crates.io/crates/bytes +[ci-badge]: https://github.com/tokio-rs/bytes/workflows/CI/badge.svg +[ci-url]: https://github.com/tokio-rs/bytes/actions + +[Documentation](https://docs.rs/bytes) + +## Usage + +To use `bytes`, first add this to your `Cargo.toml`: + +```toml +[dependencies] +bytes = "1" +``` + +Next, add this to your crate: + +```rust +use bytes::{Bytes, BytesMut, Buf, BufMut}; +``` + +## Serde support + +Serde support is optional and disabled by default. To enable use the feature `serde`. + +```toml +[dependencies] +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). + +### Contribution + +Unless you explicitly state otherwise, any contribution intentionally submitted +for inclusion in `bytes` by you, shall be licensed as MIT, without any additional +terms or conditions. diff --git a/benches/buf.rs b/benches/buf.rs new file mode 100644 index 0000000..616d187 --- /dev/null +++ b/benches/buf.rs @@ -0,0 +1,186 @@ +#![feature(test)] +#![warn(rust_2018_idioms)] + +extern crate test; + +use bytes::Buf; +use test::Bencher; + +/// Dummy Buf implementation +struct TestBuf { + buf: &'static [u8], + readlens: &'static [usize], + init_pos: usize, + pos: usize, + readlen_pos: usize, + readlen: usize, +} +impl TestBuf { + fn new(buf: &'static [u8], readlens: &'static [usize], init_pos: usize) -> TestBuf { + let mut buf = TestBuf { + buf, + readlens, + init_pos, + pos: 0, + readlen_pos: 0, + readlen: 0, + }; + buf.reset(); + buf + } + fn reset(&mut self) { + self.pos = self.init_pos; + self.readlen_pos = 0; + self.next_readlen(); + } + /// Compute the length of the next read : + /// - use the next value specified in readlens (capped by remaining) if any + /// - else the remaining + fn next_readlen(&mut self) { + self.readlen = self.buf.len() - self.pos; + if let Some(readlen) = self.readlens.get(self.readlen_pos) { + self.readlen = std::cmp::min(self.readlen, *readlen); + self.readlen_pos += 1; + } + } +} +impl Buf for TestBuf { + fn remaining(&self) -> usize { + self.buf.len() - self.pos + } + fn advance(&mut self, cnt: usize) { + self.pos += cnt; + assert!(self.pos <= self.buf.len()); + self.next_readlen(); + } + fn chunk(&self) -> &[u8] { + if self.readlen == 0 { + Default::default() + } else { + &self.buf[self.pos..self.pos + self.readlen] + } + } +} + +/// Dummy Buf implementation +/// version with methods forced to not be inlined (to simulate costly calls) +struct TestBufC { + inner: TestBuf, +} +impl TestBufC { + fn new(buf: &'static [u8], readlens: &'static [usize], init_pos: usize) -> TestBufC { + TestBufC { + inner: TestBuf::new(buf, readlens, init_pos), + } + } + fn reset(&mut self) { + self.inner.reset() + } +} +impl Buf for TestBufC { + #[inline(never)] + fn remaining(&self) -> usize { + self.inner.remaining() + } + #[inline(never)] + fn advance(&mut self, cnt: usize) { + self.inner.advance(cnt) + } + #[inline(never)] + fn chunk(&self) -> &[u8] { + self.inner.chunk() + } +} + +macro_rules! bench { + ($fname:ident, testbuf $testbuf:ident $readlens:expr, $method:ident $(,$arg:expr)*) => ( + #[bench] + fn $fname(b: &mut Bencher) { + let mut bufs = [ + $testbuf::new(&[1u8; 8+0], $readlens, 0), + $testbuf::new(&[1u8; 8+1], $readlens, 1), + $testbuf::new(&[1u8; 8+2], $readlens, 2), + $testbuf::new(&[1u8; 8+3], $readlens, 3), + $testbuf::new(&[1u8; 8+4], $readlens, 4), + $testbuf::new(&[1u8; 8+5], $readlens, 5), + $testbuf::new(&[1u8; 8+6], $readlens, 6), + $testbuf::new(&[1u8; 8+7], $readlens, 7), + ]; + b.iter(|| { + for i in 0..8 { + bufs[i].reset(); + let buf: &mut dyn Buf = &mut bufs[i]; // type erasure + test::black_box(buf.$method($($arg,)*)); + } + }) + } + ); + ($fname:ident, slice, $method:ident $(,$arg:expr)*) => ( + #[bench] + fn $fname(b: &mut Bencher) { + // buf must be long enough for one read of 8 bytes starting at pos 7 + let arr = [1u8; 8+7]; + b.iter(|| { + for i in 0..8 { + let mut buf = &arr[i..]; + let buf = &mut buf as &mut dyn Buf; // type erasure + test::black_box(buf.$method($($arg,)*)); + } + }) + } + ); + ($fname:ident, option) => ( + #[bench] + fn $fname(b: &mut Bencher) { + let data = [1u8; 1]; + b.iter(|| { + for _ in 0..8 { + let mut buf = Some(data); + let buf = &mut buf as &mut dyn Buf; // type erasure + test::black_box(buf.get_u8()); + } + }) + } + ); +} + +macro_rules! bench_group { + ($method:ident $(,$arg:expr)*) => ( + bench!(slice, slice, $method $(,$arg)*); + bench!(tbuf_1, testbuf TestBuf &[], $method $(,$arg)*); + bench!(tbuf_1_costly, testbuf TestBufC &[], $method $(,$arg)*); + bench!(tbuf_2, testbuf TestBuf &[1], $method $(,$arg)*); + bench!(tbuf_2_costly, testbuf TestBufC &[1], $method $(,$arg)*); + // bench!(tbuf_onebyone, testbuf TestBuf &[1,1,1,1,1,1,1,1], $method $(,$arg)*); + // bench!(tbuf_onebyone_costly, testbuf TestBufC &[1,1,1,1,1,1,1,1], $method $(,$arg)*); + ); +} + +mod get_u8 { + use super::*; + bench_group!(get_u8); +} +mod get_u16 { + use super::*; + bench_group!(get_u16); +} +mod get_u32 { + use super::*; + bench_group!(get_u32); +} +mod get_u64 { + use super::*; + bench_group!(get_u64); +} +mod get_f32 { + use super::*; + bench_group!(get_f32); +} +mod get_f64 { + use super::*; + bench_group!(get_f64); +} +mod get_uint24 { + use super::*; + bench_group!(get_uint, 3); +} diff --git a/benches/bytes.rs b/benches/bytes.rs new file mode 100644 index 0000000..61d1e83 --- /dev/null +++ b/benches/bytes.rs @@ -0,0 +1,120 @@ +#![feature(test)] +#![warn(rust_2018_idioms)] + +extern crate test; + +use bytes::Bytes; +use test::Bencher; + +#[bench] +fn deref_unique(b: &mut Bencher) { + let buf = Bytes::from(vec![0; 1024]); + + b.iter(|| { + for _ in 0..1024 { + test::black_box(&buf[..]); + } + }) +} + +#[bench] +fn deref_shared(b: &mut Bencher) { + let buf = Bytes::from(vec![0; 1024]); + let _b2 = buf.clone(); + + b.iter(|| { + for _ in 0..1024 { + test::black_box(&buf[..]); + } + }) +} + +#[bench] +fn deref_static(b: &mut Bencher) { + let buf = Bytes::from_static(b"hello world"); + + b.iter(|| { + for _ in 0..1024 { + test::black_box(&buf[..]); + } + }) +} + +#[bench] +fn clone_static(b: &mut Bencher) { + let bytes = + Bytes::from_static("hello world 1234567890 and have a good byte 0987654321".as_bytes()); + + b.iter(|| { + for _ in 0..1024 { + test::black_box(&bytes.clone()); + } + }) +} + +#[bench] +fn clone_shared(b: &mut Bencher) { + let bytes = Bytes::from(b"hello world 1234567890 and have a good byte 0987654321".to_vec()); + + b.iter(|| { + for _ in 0..1024 { + test::black_box(&bytes.clone()); + } + }) +} + +#[bench] +fn clone_arc_vec(b: &mut Bencher) { + use std::sync::Arc; + let bytes = Arc::new(b"hello world 1234567890 and have a good byte 0987654321".to_vec()); + + b.iter(|| { + for _ in 0..1024 { + test::black_box(&bytes.clone()); + } + }) +} + +#[bench] +fn from_long_slice(b: &mut Bencher) { + let data = [0u8; 128]; + b.bytes = data.len() as u64; + b.iter(|| { + let buf = Bytes::copy_from_slice(&data[..]); + test::black_box(buf); + }) +} + +#[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)); + } + }) +} + +#[bench] +fn slice_short_from_arc(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(1..2 + i % 10)); + } + }) +} + +#[bench] +fn split_off_and_drop(b: &mut Bencher) { + b.iter(|| { + for _ in 0..1024 { + let v = vec![10; 200]; + let mut b = Bytes::from(v); + test::black_box(b.split_off(100)); + test::black_box(b); + } + }) +} diff --git a/benches/bytes_mut.rs b/benches/bytes_mut.rs new file mode 100644 index 0000000..b069436 --- /dev/null +++ b/benches/bytes_mut.rs @@ -0,0 +1,266 @@ +#![feature(test)] +#![warn(rust_2018_idioms)] + +extern crate test; + +use bytes::{BufMut, BytesMut}; +use test::Bencher; + +#[bench] +fn alloc_small(b: &mut Bencher) { + b.iter(|| { + for _ in 0..1024 { + test::black_box(BytesMut::with_capacity(12)); + } + }) +} + +#[bench] +fn alloc_mid(b: &mut Bencher) { + b.iter(|| { + test::black_box(BytesMut::with_capacity(128)); + }) +} + +#[bench] +fn alloc_big(b: &mut Bencher) { + b.iter(|| { + test::black_box(BytesMut::with_capacity(4096)); + }) +} + +#[bench] +fn deref_unique(b: &mut Bencher) { + let mut buf = BytesMut::with_capacity(4096); + buf.put(&[0u8; 1024][..]); + + b.iter(|| { + for _ in 0..1024 { + test::black_box(&buf[..]); + } + }) +} + +#[bench] +fn deref_unique_unroll(b: &mut Bencher) { + let mut buf = BytesMut::with_capacity(4096); + buf.put(&[0u8; 1024][..]); + + b.iter(|| { + for _ in 0..128 { + test::black_box(&buf[..]); + test::black_box(&buf[..]); + test::black_box(&buf[..]); + test::black_box(&buf[..]); + test::black_box(&buf[..]); + test::black_box(&buf[..]); + test::black_box(&buf[..]); + test::black_box(&buf[..]); + } + }) +} + +#[bench] +fn deref_shared(b: &mut Bencher) { + let mut buf = BytesMut::with_capacity(4096); + buf.put(&[0u8; 1024][..]); + let _b2 = buf.split_off(1024); + + b.iter(|| { + for _ in 0..1024 { + test::black_box(&buf[..]); + } + }) +} + +#[bench] +fn deref_two(b: &mut Bencher) { + let mut buf1 = BytesMut::with_capacity(8); + buf1.put(&[0u8; 8][..]); + + let mut buf2 = BytesMut::with_capacity(4096); + buf2.put(&[0u8; 1024][..]); + + b.iter(|| { + for _ in 0..512 { + test::black_box(&buf1[..]); + test::black_box(&buf2[..]); + } + }) +} + +#[bench] +fn clone_frozen(b: &mut Bencher) { + let bytes = BytesMut::from(&b"hello world 1234567890 and have a good byte 0987654321"[..]) + .split() + .freeze(); + + b.iter(|| { + for _ in 0..1024 { + test::black_box(&bytes.clone()); + } + }) +} + +#[bench] +fn alloc_write_split_to_mid(b: &mut Bencher) { + b.iter(|| { + let mut buf = BytesMut::with_capacity(128); + buf.put_slice(&[0u8; 64]); + test::black_box(buf.split_to(64)); + }) +} + +#[bench] +fn drain_write_drain(b: &mut Bencher) { + let data = [0u8; 128]; + + b.iter(|| { + let mut buf = BytesMut::with_capacity(1024); + let mut parts = Vec::with_capacity(8); + + for _ in 0..8 { + buf.put(&data[..]); + parts.push(buf.split_to(128)); + } + + test::black_box(parts); + }) +} + +#[bench] +fn fmt_write(b: &mut Bencher) { + use std::fmt::Write; + let mut buf = BytesMut::with_capacity(128); + let s = "foo bar baz quux lorem ipsum dolor et"; + + b.bytes = s.len() as u64; + b.iter(|| { + let _ = write!(buf, "{}", s); + test::black_box(&buf); + unsafe { + buf.set_len(0); + } + }) +} + +#[bench] +fn bytes_mut_extend(b: &mut Bencher) { + let mut buf = BytesMut::with_capacity(256); + let data = [33u8; 32]; + + b.bytes = data.len() as u64 * 4; + b.iter(|| { + for _ in 0..4 { + buf.extend(&data); + } + test::black_box(&buf); + unsafe { + buf.set_len(0); + } + }); +} + +// BufMut for BytesMut vs Vec + +#[bench] +fn put_slice_bytes_mut(b: &mut Bencher) { + let mut buf = BytesMut::with_capacity(256); + let data = [33u8; 32]; + + b.bytes = data.len() as u64 * 4; + b.iter(|| { + for _ in 0..4 { + buf.put_slice(&data); + } + test::black_box(&buf); + unsafe { + buf.set_len(0); + } + }); +} + +#[bench] +fn put_u8_bytes_mut(b: &mut Bencher) { + let mut buf = BytesMut::with_capacity(256); + let cnt = 128; + + b.bytes = cnt as u64; + b.iter(|| { + for _ in 0..cnt { + buf.put_u8(b'x'); + } + test::black_box(&buf); + unsafe { + buf.set_len(0); + } + }); +} + +#[bench] +fn put_slice_vec(b: &mut Bencher) { + let mut buf = Vec::::with_capacity(256); + let data = [33u8; 32]; + + b.bytes = data.len() as u64 * 4; + b.iter(|| { + for _ in 0..4 { + buf.put_slice(&data); + } + test::black_box(&buf); + unsafe { + buf.set_len(0); + } + }); +} + +#[bench] +fn put_u8_vec(b: &mut Bencher) { + let mut buf = Vec::::with_capacity(256); + let cnt = 128; + + b.bytes = cnt as u64; + b.iter(|| { + for _ in 0..cnt { + buf.put_u8(b'x'); + } + test::black_box(&buf); + unsafe { + buf.set_len(0); + } + }); +} + +#[bench] +fn put_slice_vec_extend(b: &mut Bencher) { + let mut buf = Vec::::with_capacity(256); + let data = [33u8; 32]; + + b.bytes = data.len() as u64 * 4; + b.iter(|| { + for _ in 0..4 { + buf.extend_from_slice(&data); + } + test::black_box(&buf); + unsafe { + buf.set_len(0); + } + }); +} + +#[bench] +fn put_u8_vec_push(b: &mut Bencher) { + let mut buf = Vec::::with_capacity(256); + let cnt = 128; + + b.bytes = cnt as u64; + b.iter(|| { + for _ in 0..cnt { + buf.push(b'x'); + } + test::black_box(&buf); + unsafe { + buf.set_len(0); + } + }); +} diff --git a/ci/miri.sh b/ci/miri.sh new file mode 100755 index 0000000..0158756 --- /dev/null +++ b/ci/miri.sh @@ -0,0 +1,11 @@ +#!/bin/bash +set -e + +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 new file mode 100644 index 0000000..4421f3a --- /dev/null +++ b/ci/test-stable.sh @@ -0,0 +1,28 @@ +#!/bin/bash + +set -ex + +cmd="${1:-test}" + +# Install cargo-hack for feature flag test +host=$(rustc -Vv | grep host | sed 's/host: //') +curl -LsSf https://github.com/taiki-e/cargo-hack/releases/latest/download/cargo-hack-$host.tar.gz | tar xzf - -C ~/.cargo/bin + +# Run with each feature +# * --each-feature includes both default/no-default features +# * --optional-deps is needed for serde feature +cargo hack "${cmd}" --each-feature --optional-deps +# Run with all features +cargo "${cmd}" --all-features + +cargo doc --no-deps --all-features + +if [[ "${RUST_VERSION}" == "nightly"* ]]; then + # Check benchmarks + cargo check --benches + + # Check minimal versions + cargo clean + cargo update -Zminimal-versions + cargo check --all-features +fi diff --git a/ci/tsan.sh b/ci/tsan.sh new file mode 100644 index 0000000..ca520bd --- /dev/null +++ b/ci/tsan.sh @@ -0,0 +1,13 @@ +#!/bin/bash + +set -ex + +export ASAN_OPTIONS="detect_odr_violation=0 detect_leaks=0" + +# Run address sanitizer +RUSTFLAGS="-Z sanitizer=address" \ +cargo test --target x86_64-unknown-linux-gnu --test test_bytes --test test_buf --test test_buf_mut + +# Run thread sanitizer +RUSTFLAGS="-Z sanitizer=thread" \ +cargo -Zbuild-std test --target x86_64-unknown-linux-gnu --test test_bytes --test test_buf --test test_buf_mut diff --git a/clippy.toml b/clippy.toml new file mode 100644 index 0000000..53095b1 --- /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 new file mode 100644 index 0000000..366cfc9 --- /dev/null +++ b/src/buf/buf_impl.rs @@ -0,0 +1,1394 @@ +#[cfg(feature = "std")] +use crate::buf::{reader, Reader}; +use crate::buf::{take, Chain, Take}; + +use core::{cmp, mem, ptr}; + +#[cfg(feature = "std")] +use std::io::IoSlice; + +use alloc::boxed::Box; + +macro_rules! buf_get_impl { + ($this:ident, $typ:tt::$conv:tt) => {{ + const SIZE: usize = mem::size_of::<$typ>(); + // try to convert directly from the bytes + // this Option trick is to avoid keeping a borrow on self + // when advance() is called (mut borrow) and to call bytes() only once + let ret = $this + .chunk() + .get(..SIZE) + .map(|src| unsafe { $typ::$conv(*(src as *const _ as *const [_; SIZE])) }); + + if let Some(ret) = ret { + // if the direct conversion was possible, advance and return + $this.advance(SIZE); + return ret; + } else { + // if not we copy the bytes in a temp buffer then convert + let mut buf = [0; SIZE]; + $this.copy_to_slice(&mut buf); // (do the advance) + return $typ::$conv(buf); + } + }}; + (le => $this:ident, $typ:tt, $len_to_read:expr) => {{ + debug_assert!(mem::size_of::<$typ>() >= $len_to_read); + + // The same trick as above does not improve the best case speed. + // It seems to be linked to the way the method is optimised by the compiler + let mut buf = [0; (mem::size_of::<$typ>())]; + $this.copy_to_slice(&mut buf[..($len_to_read)]); + return $typ::from_le_bytes(buf); + }}; + (be => $this:ident, $typ:tt, $len_to_read:expr) => {{ + debug_assert!(mem::size_of::<$typ>() >= $len_to_read); + + let mut buf = [0; (mem::size_of::<$typ>())]; + $this.copy_to_slice(&mut buf[mem::size_of::<$typ>() - ($len_to_read)..]); + return $typ::from_be_bytes(buf); + }}; +} + +/// Read bytes from a buffer. +/// +/// A buffer stores bytes in memory such that read operations are infallible. +/// The underlying storage may or may not be in contiguous memory. A `Buf` value +/// is a cursor into the buffer. Reading from `Buf` advances the cursor +/// position. It can be thought of as an efficient `Iterator` for collections of +/// bytes. +/// +/// The simplest `Buf` is a `&[u8]`. +/// +/// ``` +/// use bytes::Buf; +/// +/// let mut buf = &b"hello world"[..]; +/// +/// assert_eq!(b'h', buf.get_u8()); +/// assert_eq!(b'e', buf.get_u8()); +/// assert_eq!(b'l', buf.get_u8()); +/// +/// let mut rest = [0; 8]; +/// buf.copy_to_slice(&mut rest); +/// +/// assert_eq!(&rest[..], &b"lo world"[..]); +/// ``` +pub trait Buf { + /// Returns the number of bytes between the current position and the end of + /// the buffer. + /// + /// This value is greater than or equal to the length of the slice returned + /// by `chunk()`. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"hello world"[..]; + /// + /// assert_eq!(buf.remaining(), 11); + /// + /// buf.get_u8(); + /// + /// assert_eq!(buf.remaining(), 10); + /// ``` + /// + /// # Implementer notes + /// + /// Implementations of `remaining` should ensure that the return value does + /// not change unless a call is made to `advance` or any other function that + /// is documented to change the `Buf`'s current position. + fn remaining(&self) -> usize; + + /// Returns a slice starting at the current position and of length between 0 + /// and `Buf::remaining()`. Note that this *can* return shorter slice (this allows + /// non-continuous internal representation). + /// + /// This is a lower level function. Most operations are done with other + /// functions. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"hello world"[..]; + /// + /// assert_eq!(buf.chunk(), &b"hello world"[..]); + /// + /// buf.advance(6); + /// + /// assert_eq!(buf.chunk(), &b"world"[..]); + /// ``` + /// + /// # Implementer notes + /// + /// This function should never panic. Once the end of the buffer is reached, + /// i.e., `Buf::remaining` returns 0, calls to `chunk()` should return an + /// empty slice. + // The `chunk` method was previously called `bytes`. This alias makes the rename + // more easily discoverable. + #[cfg_attr(docsrs, doc(alias = "bytes"))] + fn chunk(&self) -> &[u8]; + + /// Fills `dst` with potentially multiple slices starting at `self`'s + /// current position. + /// + /// If the `Buf` is backed by disjoint slices of bytes, `chunk_vectored` enables + /// fetching more than one slice at once. `dst` is a slice of `IoSlice` + /// references, enabling the slice to be directly used with [`writev`] + /// without any further conversion. The sum of the lengths of all the + /// buffers in `dst` will be less than or equal to `Buf::remaining()`. + /// + /// The entries in `dst` will be overwritten, but the data **contained** by + /// the slices **will not** be modified. If `chunk_vectored` does not fill every + /// entry in `dst`, then `dst` is guaranteed to contain all remaining slices + /// in `self. + /// + /// This is a lower level function. Most operations are done with other + /// functions. + /// + /// # Implementer notes + /// + /// This function should never panic. Once the end of the buffer is reached, + /// i.e., `Buf::remaining` returns 0, calls to `chunk_vectored` must return 0 + /// without mutating `dst`. + /// + /// Implementations should also take care to properly handle being called + /// with `dst` being a zero length slice. + /// + /// [`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; + } + + if self.has_remaining() { + dst[0] = IoSlice::new(self.chunk()); + 1 + } else { + 0 + } + } + + /// Advance the internal cursor of the Buf + /// + /// The next call to `chunk()` will return a slice starting `cnt` bytes + /// further into the underlying buffer. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"hello world"[..]; + /// + /// assert_eq!(buf.chunk(), &b"hello world"[..]); + /// + /// buf.advance(6); + /// + /// assert_eq!(buf.chunk(), &b"world"[..]); + /// ``` + /// + /// # Panics + /// + /// This function **may** panic if `cnt > self.remaining()`. + /// + /// # Implementer notes + /// + /// It is recommended for implementations of `advance` to panic if `cnt > + /// self.remaining()`. If the implementation does not panic, the call must + /// behave as if `cnt == self.remaining()`. + /// + /// A call with `cnt == 0` should never panic and be a no-op. + fn advance(&mut self, cnt: usize); + + /// Returns true if there are any more bytes to consume + /// + /// This is equivalent to `self.remaining() != 0`. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"a"[..]; + /// + /// assert!(buf.has_remaining()); + /// + /// buf.get_u8(); + /// + /// assert!(!buf.has_remaining()); + /// ``` + fn has_remaining(&self) -> bool { + self.remaining() > 0 + } + + /// Copies bytes from `self` into `dst`. + /// + /// The cursor is advanced by the number of bytes copied. `self` must have + /// enough remaining bytes to fill `dst`. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"hello world"[..]; + /// let mut dst = [0; 5]; + /// + /// buf.copy_to_slice(&mut dst); + /// assert_eq!(&b"hello"[..], &dst); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// # Panics + /// + /// This function panics if `self.remaining() < dst.len()` + fn copy_to_slice(&mut self, dst: &mut [u8]) { + let mut off = 0; + + assert!(self.remaining() >= dst.len()); + + while off < dst.len() { + let cnt; + + unsafe { + let src = self.chunk(); + cnt = cmp::min(src.len(), dst.len() - off); + + ptr::copy_nonoverlapping(src.as_ptr(), dst[off..].as_mut_ptr(), cnt); + + off += cnt; + } + + self.advance(cnt); + } + } + + /// Gets an unsigned 8 bit integer from `self`. + /// + /// The current position is advanced by 1. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x08 hello"[..]; + /// assert_eq!(8, buf.get_u8()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is no more remaining data in `self`. + fn get_u8(&mut self) -> u8 { + assert!(self.remaining() >= 1); + let ret = self.chunk()[0]; + self.advance(1); + ret + } + + /// Gets a signed 8 bit integer from `self`. + /// + /// The current position is advanced by 1. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x08 hello"[..]; + /// assert_eq!(8, buf.get_i8()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is no more remaining data in `self`. + fn get_i8(&mut self) -> i8 { + assert!(self.remaining() >= 1); + let ret = self.chunk()[0] as i8; + self.advance(1); + ret + } + + /// Gets an unsigned 16 bit integer from `self` in big-endian byte order. + /// + /// The current position is advanced by 2. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x08\x09 hello"[..]; + /// assert_eq!(0x0809, buf.get_u16()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_u16(&mut self) -> u16 { + buf_get_impl!(self, u16::from_be_bytes); + } + + /// Gets an unsigned 16 bit integer from `self` in little-endian byte order. + /// + /// The current position is advanced by 2. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x09\x08 hello"[..]; + /// assert_eq!(0x0809, buf.get_u16_le()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_u16_le(&mut self) -> u16 { + 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. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x08\x09 hello"[..]; + /// assert_eq!(0x0809, buf.get_i16()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_i16(&mut self) -> i16 { + buf_get_impl!(self, i16::from_be_bytes); + } + + /// Gets a signed 16 bit integer from `self` in little-endian byte order. + /// + /// The current position is advanced by 2. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x09\x08 hello"[..]; + /// assert_eq!(0x0809, buf.get_i16_le()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_i16_le(&mut self) -> i16 { + 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. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x08\x09\xA0\xA1 hello"[..]; + /// assert_eq!(0x0809A0A1, buf.get_u32()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_u32(&mut self) -> u32 { + buf_get_impl!(self, u32::from_be_bytes); + } + + /// Gets an unsigned 32 bit integer from `self` in the little-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\xA1\xA0\x09\x08 hello"[..]; + /// assert_eq!(0x0809A0A1, buf.get_u32_le()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_u32_le(&mut self) -> u32 { + 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. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x08\x09\xA0\xA1 hello"[..]; + /// assert_eq!(0x0809A0A1, buf.get_i32()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_i32(&mut self) -> i32 { + buf_get_impl!(self, i32::from_be_bytes); + } + + /// Gets a signed 32 bit integer from `self` in little-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\xA1\xA0\x09\x08 hello"[..]; + /// assert_eq!(0x0809A0A1, buf.get_i32_le()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_i32_le(&mut self) -> i32 { + 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. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x01\x02\x03\x04\x05\x06\x07\x08 hello"[..]; + /// assert_eq!(0x0102030405060708, buf.get_u64()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_u64(&mut self) -> u64 { + buf_get_impl!(self, u64::from_be_bytes); + } + + /// Gets an unsigned 64 bit integer from `self` in little-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x08\x07\x06\x05\x04\x03\x02\x01 hello"[..]; + /// assert_eq!(0x0102030405060708, buf.get_u64_le()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_u64_le(&mut self) -> u64 { + 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. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x01\x02\x03\x04\x05\x06\x07\x08 hello"[..]; + /// assert_eq!(0x0102030405060708, buf.get_i64()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_i64(&mut self) -> i64 { + buf_get_impl!(self, i64::from_be_bytes); + } + + /// Gets a signed 64 bit integer from `self` in little-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x08\x07\x06\x05\x04\x03\x02\x01 hello"[..]; + /// assert_eq!(0x0102030405060708, buf.get_i64_le()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_i64_le(&mut self) -> i64 { + 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. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16 hello"[..]; + /// assert_eq!(0x01020304050607080910111213141516, buf.get_u128()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_u128(&mut self) -> u128 { + buf_get_impl!(self, u128::from_be_bytes); + } + + /// Gets an unsigned 128 bit integer from `self` in little-endian byte order. + /// + /// The current position is advanced by 16. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02\x01 hello"[..]; + /// assert_eq!(0x01020304050607080910111213141516, buf.get_u128_le()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_u128_le(&mut self) -> u128 { + 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. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16 hello"[..]; + /// assert_eq!(0x01020304050607080910111213141516, buf.get_i128()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_i128(&mut self) -> i128 { + buf_get_impl!(self, i128::from_be_bytes); + } + + /// Gets a signed 128 bit integer from `self` in little-endian byte order. + /// + /// The current position is advanced by 16. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02\x01 hello"[..]; + /// assert_eq!(0x01020304050607080910111213141516, buf.get_i128_le()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_i128_le(&mut self) -> i128 { + 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`. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x01\x02\x03 hello"[..]; + /// assert_eq!(0x010203, buf.get_uint(3)); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_uint(&mut self, nbytes: usize) -> u64 { + buf_get_impl!(be => self, u64, nbytes); + } + + /// Gets an unsigned n-byte integer from `self` in little-endian byte order. + /// + /// The current position is advanced by `nbytes`. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x03\x02\x01 hello"[..]; + /// assert_eq!(0x010203, buf.get_uint_le(3)); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_uint_le(&mut self, nbytes: usize) -> u64 { + 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`. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x01\x02\x03 hello"[..]; + /// assert_eq!(0x010203, buf.get_int(3)); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_int(&mut self, nbytes: usize) -> i64 { + buf_get_impl!(be => self, i64, nbytes); + } + + /// Gets a signed n-byte integer from `self` in little-endian byte order. + /// + /// The current position is advanced by `nbytes`. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x03\x02\x01 hello"[..]; + /// assert_eq!(0x010203, buf.get_int_le(3)); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_int_le(&mut self, nbytes: usize) -> i64 { + 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. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x3F\x99\x99\x9A hello"[..]; + /// assert_eq!(1.2f32, buf.get_f32()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_f32(&mut self) -> f32 { + f32::from_bits(Self::get_u32(self)) + } + + /// Gets an IEEE754 single-precision (4 bytes) floating point number from + /// `self` in little-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x9A\x99\x99\x3F hello"[..]; + /// assert_eq!(1.2f32, buf.get_f32_le()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_f32_le(&mut self) -> f32 { + 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. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x3F\xF3\x33\x33\x33\x33\x33\x33 hello"[..]; + /// assert_eq!(1.2f64, buf.get_f64()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_f64(&mut self) -> f64 { + f64::from_bits(Self::get_u64(self)) + } + + /// Gets an IEEE754 double-precision (8 bytes) floating point number from + /// `self` in little-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x33\x33\x33\x33\x33\x33\xF3\x3F hello"[..]; + /// assert_eq!(1.2f64, buf.get_f64_le()); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining data in `self`. + fn get_f64_le(&mut self) -> f64 { + 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. + /// + /// This function may be optimized by the underlying type to avoid actual + /// copies. For example, `Bytes` implementation will do a shallow copy + /// (ref-count increment). + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let bytes = (&b"hello world"[..]).copy_to_bytes(5); + /// assert_eq!(&bytes[..], &b"hello"[..]); + /// ``` + fn copy_to_bytes(&mut self, len: usize) -> crate::Bytes { + use super::BufMut; + + assert!(len <= self.remaining(), "`len` greater than remaining"); + + let mut ret = crate::BytesMut::with_capacity(len); + ret.put(self.take(len)); + ret.freeze() + } + + /// Creates an adaptor which will read at most `limit` bytes from `self`. + /// + /// This function returns a new instance of `Buf` which will read at most + /// `limit` bytes. + /// + /// # Examples + /// + /// ``` + /// use bytes::{Buf, BufMut}; + /// + /// let mut buf = b"hello world"[..].take(5); + /// let mut dst = vec![]; + /// + /// dst.put(&mut buf); + /// assert_eq!(dst, b"hello"); + /// + /// let mut buf = buf.into_inner(); + /// dst.clear(); + /// dst.put(&mut buf); + /// assert_eq!(dst, b" world"); + /// ``` + fn take(self, limit: usize) -> Take + where + Self: Sized, + { + take::new(self, limit) + } + + /// Creates an adaptor which will chain this buffer with another. + /// + /// The returned `Buf` instance will first consume all bytes from `self`. + /// Afterwards the output is equivalent to the output of next. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut chain = b"hello "[..].chain(&b"world"[..]); + /// + /// let full = chain.copy_to_bytes(11); + /// assert_eq!(full.chunk(), b"hello world"); + /// ``` + fn chain(self, next: U) -> Chain + where + Self: Sized, + { + Chain::new(self, next) + } + + /// Creates an adaptor which implements the `Read` trait for `self`. + /// + /// This function returns a new value which implements `Read` by adapting + /// the `Read` trait functions to the `Buf` trait functions. Given that + /// `Buf` operations are infallible, none of the `Read` functions will + /// return with `Err`. + /// + /// # Examples + /// + /// ``` + /// use bytes::{Bytes, Buf}; + /// use std::io::Read; + /// + /// let buf = Bytes::from("hello world"); + /// + /// let mut reader = buf.reader(); + /// let mut dst = [0; 1024]; + /// + /// let num = reader.read(&mut dst).unwrap(); + /// + /// assert_eq!(11, num); + /// assert_eq!(&dst[..11], &b"hello world"[..]); + /// ``` + #[cfg(feature = "std")] + #[cfg_attr(docsrs, doc(cfg(feature = "std")))] + fn reader(self) -> Reader + where + Self: Sized, + { + reader::new(self) + } +} + +macro_rules! deref_forward_buf { + () => { + fn remaining(&self) -> usize { + (**self).remaining() + } + + fn chunk(&self) -> &[u8] { + (**self).chunk() + } + + #[cfg(feature = "std")] + fn chunks_vectored<'b>(&'b self, dst: &mut [IoSlice<'b>]) -> usize { + (**self).chunks_vectored(dst) + } + + fn advance(&mut self, cnt: usize) { + (**self).advance(cnt) + } + + fn has_remaining(&self) -> bool { + (**self).has_remaining() + } + + fn copy_to_slice(&mut self, dst: &mut [u8]) { + (**self).copy_to_slice(dst) + } + + fn get_u8(&mut self) -> u8 { + (**self).get_u8() + } + + fn get_i8(&mut self) -> i8 { + (**self).get_i8() + } + + fn get_u16(&mut self) -> u16 { + (**self).get_u16() + } + + fn get_u16_le(&mut self) -> u16 { + (**self).get_u16_le() + } + + fn get_u16_ne(&mut self) -> u16 { + (**self).get_u16_ne() + } + + fn get_i16(&mut self) -> i16 { + (**self).get_i16() + } + + fn get_i16_le(&mut self) -> i16 { + (**self).get_i16_le() + } + + fn get_i16_ne(&mut self) -> i16 { + (**self).get_i16_ne() + } + + fn get_u32(&mut self) -> u32 { + (**self).get_u32() + } + + fn get_u32_le(&mut self) -> u32 { + (**self).get_u32_le() + } + + fn get_u32_ne(&mut self) -> u32 { + (**self).get_u32_ne() + } + + fn get_i32(&mut self) -> i32 { + (**self).get_i32() + } + + fn get_i32_le(&mut self) -> i32 { + (**self).get_i32_le() + } + + fn get_i32_ne(&mut self) -> i32 { + (**self).get_i32_ne() + } + + fn get_u64(&mut self) -> u64 { + (**self).get_u64() + } + + fn get_u64_le(&mut self) -> u64 { + (**self).get_u64_le() + } + + fn get_u64_ne(&mut self) -> u64 { + (**self).get_u64_ne() + } + + fn get_i64(&mut self) -> i64 { + (**self).get_i64() + } + + fn get_i64_le(&mut self) -> i64 { + (**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) + } + + fn get_uint_le(&mut self, nbytes: usize) -> u64 { + (**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) + } + + fn get_int_le(&mut self, nbytes: usize) -> i64 { + (**self).get_int_le(nbytes) + } + + fn get_int_ne(&mut self, nbytes: usize) -> i64 { + (**self).get_int_ne(nbytes) + } + + fn copy_to_bytes(&mut self, len: usize) -> crate::Bytes { + (**self).copy_to_bytes(len) + } + }; +} + +impl Buf for &mut T { + deref_forward_buf!(); +} + +impl Buf for Box { + deref_forward_buf!(); +} + +impl Buf for &[u8] { + #[inline] + fn remaining(&self) -> usize { + self.len() + } + + #[inline] + fn chunk(&self) -> &[u8] { + self + } + + #[inline] + fn advance(&mut self, cnt: usize) { + *self = &self[cnt..]; + } +} + +#[cfg(feature = "std")] +impl> Buf for std::io::Cursor { + fn remaining(&self) -> usize { + let len = self.get_ref().as_ref().len(); + let pos = self.position(); + + if pos >= len as u64 { + return 0; + } + + len - pos as usize + } + + fn chunk(&self) -> &[u8] { + let len = self.get_ref().as_ref().len(); + let pos = self.position(); + + if pos >= len as u64 { + return &[]; + } + + &self.get_ref().as_ref()[pos as usize..] + } + + fn advance(&mut self, cnt: usize) { + let pos = (self.position() as usize) + .checked_add(cnt) + .expect("overflow"); + + assert!(pos <= self.get_ref().as_ref().len()); + self.set_position(pos as u64); + } +} + +// The existence of this function makes the compiler catch if the Buf +// trait is "object-safe" or not. +fn _assert_trait_object(_b: &dyn Buf) {} diff --git a/src/buf/buf_mut.rs b/src/buf/buf_mut.rs new file mode 100644 index 0000000..685fcc7 --- /dev/null +++ b/src/buf/buf_mut.rs @@ -0,0 +1,1493 @@ +use crate::buf::{limit, Chain, Limit, UninitSlice}; +#[cfg(feature = "std")] +use crate::buf::{writer, Writer}; + +use core::{cmp, mem, ptr, usize}; + +use alloc::{boxed::Box, vec::Vec}; + +/// A trait for values that provide sequential write access to bytes. +/// +/// Write bytes to a buffer +/// +/// A buffer stores bytes in memory such that write operations are infallible. +/// The underlying storage may or may not be in contiguous memory. A `BufMut` +/// value is a cursor into the buffer. Writing to `BufMut` advances the cursor +/// position. +/// +/// The simplest `BufMut` is a `Vec`. +/// +/// ``` +/// use bytes::BufMut; +/// +/// let mut buf = vec![]; +/// +/// buf.put(&b"hello world"[..]); +/// +/// assert_eq!(buf, b"hello world"); +/// ``` +pub unsafe trait BufMut { + /// Returns the number of bytes that can be written from the current + /// position until the end of the buffer is reached. + /// + /// This value is greater than or equal to the length of the slice returned + /// by `chunk_mut()`. + /// + /// Writing to a `BufMut` may involve allocating more memory on the fly. + /// Implementations may fail before reaching the number of bytes indicated + /// by this method if they encounter an allocation failure. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut dst = [0; 10]; + /// let mut buf = &mut dst[..]; + /// + /// let original_remaining = buf.remaining_mut(); + /// buf.put(&b"hello"[..]); + /// + /// assert_eq!(original_remaining - 5, buf.remaining_mut()); + /// ``` + /// + /// # Implementer notes + /// + /// 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 + /// + /// The next call to `chunk_mut` will return a slice starting `cnt` bytes + /// further into the underlying buffer. + /// + /// This function is unsafe because there is no guarantee that the bytes + /// being advanced past have been initialized. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = Vec::with_capacity(16); + /// + /// // Write some data + /// buf.chunk_mut()[0..2].copy_from_slice(b"he"); + /// unsafe { buf.advance_mut(2) }; + /// + /// // write more bytes + /// buf.chunk_mut()[0..3].copy_from_slice(b"llo"); + /// + /// unsafe { buf.advance_mut(3); } + /// + /// assert_eq!(5, buf.len()); + /// assert_eq!(buf, b"hello"); + /// ``` + /// + /// # Panics + /// + /// This function **may** panic if `cnt > self.remaining_mut()`. + /// + /// # Implementer notes + /// + /// It is recommended for implementations of `advance_mut` to panic if + /// `cnt > self.remaining_mut()`. If the implementation does not panic, + /// the call must behave as if `cnt == self.remaining_mut()`. + /// + /// A call with `cnt == 0` should never panic and be a no-op. + unsafe fn advance_mut(&mut self, cnt: usize); + + /// Returns true if there is space in `self` for more bytes. + /// + /// This is equivalent to `self.remaining_mut() != 0`. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut dst = [0; 5]; + /// let mut buf = &mut dst[..]; + /// + /// assert!(buf.has_remaining_mut()); + /// + /// buf.put(&b"hello"[..]); + /// + /// assert!(!buf.has_remaining_mut()); + /// ``` + fn has_remaining_mut(&self) -> bool { + self.remaining_mut() > 0 + } + + /// Returns a mutable slice starting at the current BufMut position and of + /// length between 0 and `BufMut::remaining_mut()`. Note that this *can* be shorter than the + /// whole remainder of the buffer (this allows non-continuous implementation). + /// + /// This is a lower level function. Most operations are done with other + /// functions. + /// + /// The returned byte slice may represent uninitialized memory. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = Vec::with_capacity(16); + /// + /// unsafe { + /// // MaybeUninit::as_mut_ptr + /// buf.chunk_mut()[0..].as_mut_ptr().write(b'h'); + /// buf.chunk_mut()[1..].as_mut_ptr().write(b'e'); + /// + /// buf.advance_mut(2); + /// + /// buf.chunk_mut()[0..].as_mut_ptr().write(b'l'); + /// buf.chunk_mut()[1..].as_mut_ptr().write(b'l'); + /// buf.chunk_mut()[2..].as_mut_ptr().write(b'o'); + /// + /// buf.advance_mut(3); + /// } + /// + /// assert_eq!(5, buf.len()); + /// assert_eq!(buf, b"hello"); + /// ``` + /// + /// # Implementer notes + /// + /// This function should never panic. `chunk_mut` should return an empty + /// slice **if and only if** `remaining_mut()` returns 0. In other words, + /// `chunk_mut()` returning an empty slice implies that `remaining_mut()` will + /// return 0 and `remaining_mut()` returning 0 implies that `chunk_mut()` will + /// return an empty slice. + /// + /// This function may trigger an out-of-memory abort if it tries to allocate + /// memory and fails to do so. + // The `chunk_mut` method was previously called `bytes_mut`. This alias makes the + // rename more easily discoverable. + #[cfg_attr(docsrs, doc(alias = "bytes_mut"))] + fn chunk_mut(&mut self) -> &mut UninitSlice; + + /// Transfer bytes into `self` from `src` and advance the cursor by the + /// number of bytes written. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// + /// buf.put_u8(b'h'); + /// buf.put(&b"ello"[..]); + /// buf.put(&b" world"[..]); + /// + /// assert_eq!(buf, b"hello world"); + /// ``` + /// + /// # Panics + /// + /// Panics if `self` does not have enough capacity to contain `src`. + fn put(&mut self, mut src: T) + where + Self: Sized, + { + assert!(self.remaining_mut() >= src.remaining()); + + while src.has_remaining() { + let l; + + unsafe { + let s = src.chunk(); + let d = self.chunk_mut(); + l = cmp::min(s.len(), d.len()); + + ptr::copy_nonoverlapping(s.as_ptr(), d.as_mut_ptr() as *mut u8, l); + } + + src.advance(l); + unsafe { + self.advance_mut(l); + } + } + } + + /// Transfer bytes into `self` from `src` and advance the cursor by the + /// number of bytes written. + /// + /// `self` must have enough remaining capacity to contain all of `src`. + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut dst = [0; 6]; + /// + /// { + /// let mut buf = &mut dst[..]; + /// buf.put_slice(b"hello"); + /// + /// assert_eq!(1, buf.remaining_mut()); + /// } + /// + /// assert_eq!(b"hello\0", &dst); + /// ``` + fn put_slice(&mut self, src: &[u8]) { + let mut off = 0; + + assert!( + self.remaining_mut() >= src.len(), + "buffer overflow; remaining = {}; src = {}", + self.remaining_mut(), + src.len() + ); + + while off < src.len() { + let cnt; + + unsafe { + let dst = self.chunk_mut(); + cnt = cmp::min(dst.len(), src.len() - off); + + ptr::copy_nonoverlapping(src[off..].as_ptr(), dst.as_mut_ptr() as *mut u8, cnt); + + off += cnt; + } + + unsafe { + self.advance_mut(cnt); + } + } + } + + /// 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. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u8(0x01); + /// assert_eq!(buf, b"\x01"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u8(&mut self, n: u8) { + let src = [n]; + self.put_slice(&src); + } + + /// Writes a signed 8 bit integer to `self`. + /// + /// The current position is advanced by 1. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i8(0x01); + /// assert_eq!(buf, b"\x01"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i8(&mut self, n: i8) { + let src = [n as u8]; + self.put_slice(&src) + } + + /// Writes an unsigned 16 bit integer to `self` in big-endian byte order. + /// + /// The current position is advanced by 2. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u16(0x0809); + /// assert_eq!(buf, b"\x08\x09"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u16(&mut self, n: u16) { + self.put_slice(&n.to_be_bytes()) + } + + /// Writes an unsigned 16 bit integer to `self` in little-endian byte order. + /// + /// The current position is advanced by 2. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u16_le(0x0809); + /// assert_eq!(buf, b"\x09\x08"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u16_le(&mut self, n: u16) { + 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. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i16(0x0809); + /// assert_eq!(buf, b"\x08\x09"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i16(&mut self, n: i16) { + self.put_slice(&n.to_be_bytes()) + } + + /// Writes a signed 16 bit integer to `self` in little-endian byte order. + /// + /// The current position is advanced by 2. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i16_le(0x0809); + /// assert_eq!(buf, b"\x09\x08"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i16_le(&mut self, n: i16) { + 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. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u32(0x0809A0A1); + /// assert_eq!(buf, b"\x08\x09\xA0\xA1"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u32(&mut self, n: u32) { + self.put_slice(&n.to_be_bytes()) + } + + /// Writes an unsigned 32 bit integer to `self` in little-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u32_le(0x0809A0A1); + /// assert_eq!(buf, b"\xA1\xA0\x09\x08"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u32_le(&mut self, n: u32) { + 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. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i32(0x0809A0A1); + /// assert_eq!(buf, b"\x08\x09\xA0\xA1"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i32(&mut self, n: i32) { + self.put_slice(&n.to_be_bytes()) + } + + /// Writes a signed 32 bit integer to `self` in little-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i32_le(0x0809A0A1); + /// assert_eq!(buf, b"\xA1\xA0\x09\x08"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i32_le(&mut self, n: i32) { + 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. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u64(0x0102030405060708); + /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u64(&mut self, n: u64) { + self.put_slice(&n.to_be_bytes()) + } + + /// Writes an unsigned 64 bit integer to `self` in little-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u64_le(0x0102030405060708); + /// 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_le(&mut self, n: u64) { + 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. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i64(0x0102030405060708); + /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i64(&mut self, n: i64) { + self.put_slice(&n.to_be_bytes()) + } + + /// Writes a signed 64 bit integer to `self` in little-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i64_le(0x0102030405060708); + /// 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_le(&mut self, n: i64) { + 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. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u128(0x01020304050607080910111213141516); + /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_u128(&mut self, n: u128) { + self.put_slice(&n.to_be_bytes()) + } + + /// Writes an unsigned 128 bit integer to `self` in little-endian byte order. + /// + /// The current position is advanced by 16. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_u128_le(0x01020304050607080910111213141516); + /// 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_le(&mut self, n: u128) { + 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. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i128(0x01020304050607080910111213141516); + /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_i128(&mut self, n: i128) { + self.put_slice(&n.to_be_bytes()) + } + + /// Writes a signed 128 bit integer to `self` in little-endian byte order. + /// + /// The current position is advanced by 16. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_i128_le(0x01020304050607080910111213141516); + /// 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_le(&mut self, n: i128) { + 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`. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_uint(0x010203, 3); + /// assert_eq!(buf, b"\x01\x02\x03"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_uint(&mut self, n: u64, nbytes: usize) { + self.put_slice(&n.to_be_bytes()[mem::size_of_val(&n) - nbytes..]); + } + + /// Writes an unsigned n-byte integer to `self` in the little-endian byte order. + /// + /// The current position is advanced by `nbytes`. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_uint_le(0x010203, 3); + /// assert_eq!(buf, b"\x03\x02\x01"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_uint_le(&mut self, n: u64, nbytes: usize) { + self.put_slice(&n.to_le_bytes()[0..nbytes]); + } + + /// Writes an unsigned n-byte integer to `self` in the native-endian byte order. + /// + /// The current position is advanced by `nbytes`. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// 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 low `nbytes` of a signed integer to `self` in little-endian byte order. + /// + /// The current position is advanced by `nbytes`. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// 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` 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. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_f32(1.2f32); + /// assert_eq!(buf, b"\x3F\x99\x99\x9A"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_f32(&mut self, n: f32) { + self.put_u32(n.to_bits()); + } + + /// Writes an IEEE754 single-precision (4 bytes) floating point number to + /// `self` in little-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_f32_le(1.2f32); + /// assert_eq!(buf, b"\x9A\x99\x99\x3F"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_f32_le(&mut self, n: f32) { + 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. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_f64(1.2f64); + /// assert_eq!(buf, b"\x3F\xF3\x33\x33\x33\x33\x33\x33"); + /// ``` + /// + /// # Panics + /// + /// This function panics if there is not enough remaining capacity in + /// `self`. + fn put_f64(&mut self, n: f64) { + self.put_u64(n.to_bits()); + } + + /// Writes an IEEE754 double-precision (8 bytes) floating point number to + /// `self` in little-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut buf = vec![]; + /// buf.put_f64_le(1.2f64); + /// 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_le(&mut self, n: f64) { + 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 + /// + /// ``` + /// use bytes::BufMut; + /// + /// let arr = &mut [0u8; 128][..]; + /// assert_eq!(arr.remaining_mut(), 128); + /// + /// let dst = arr.limit(10); + /// assert_eq!(dst.remaining_mut(), 10); + /// ``` + fn limit(self, limit: usize) -> Limit + where + Self: Sized, + { + limit::new(self, limit) + } + + /// Creates an adaptor which implements the `Write` trait for `self`. + /// + /// This function returns a new value which implements `Write` by adapting + /// the `Write` trait functions to the `BufMut` trait functions. Given that + /// `BufMut` operations are infallible, none of the `Write` functions will + /// return with `Err`. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// use std::io::Write; + /// + /// let mut buf = vec![].writer(); + /// + /// let num = buf.write(&b"hello world"[..]).unwrap(); + /// assert_eq!(11, num); + /// + /// let buf = buf.into_inner(); + /// + /// assert_eq!(*buf, b"hello world"[..]); + /// ``` + #[cfg(feature = "std")] + #[cfg_attr(docsrs, doc(cfg(feature = "std")))] + fn writer(self) -> Writer + where + Self: Sized, + { + writer::new(self) + } + + /// Creates an adapter which will chain this buffer with another. + /// + /// The returned `BufMut` instance will first write to all bytes from + /// `self`. Afterwards, it will write to `next`. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut a = [0u8; 5]; + /// let mut b = [0u8; 6]; + /// + /// let mut chain = (&mut a[..]).chain_mut(&mut b[..]); + /// + /// chain.put_slice(b"hello world"); + /// + /// assert_eq!(&a[..], b"hello"); + /// assert_eq!(&b[..], b" world"); + /// ``` + fn chain_mut(self, next: U) -> Chain + where + Self: Sized, + { + Chain::new(self, next) + } +} + +macro_rules! deref_forward_bufmut { + () => { + fn remaining_mut(&self) -> usize { + (**self).remaining_mut() + } + + fn chunk_mut(&mut self) -> &mut UninitSlice { + (**self).chunk_mut() + } + + unsafe fn advance_mut(&mut self, cnt: usize) { + (**self).advance_mut(cnt) + } + + fn put_slice(&mut self, src: &[u8]) { + (**self).put_slice(src) + } + + fn put_u8(&mut self, n: u8) { + (**self).put_u8(n) + } + + fn put_i8(&mut self, n: i8) { + (**self).put_i8(n) + } + + fn put_u16(&mut self, n: u16) { + (**self).put_u16(n) + } + + fn put_u16_le(&mut self, n: u16) { + (**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) + } + + fn put_i16_le(&mut self, n: i16) { + (**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) + } + + fn put_u32_le(&mut self, n: u32) { + (**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) + } + + fn put_i32_le(&mut self, n: i32) { + (**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) + } + + fn put_u64_le(&mut self, n: u64) { + (**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) + } + + 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) + } + }; +} + +unsafe impl BufMut for &mut T { + deref_forward_bufmut!(); +} + +unsafe impl BufMut for Box { + deref_forward_bufmut!(); +} + +unsafe impl BufMut for &mut [u8] { + #[inline] + fn remaining_mut(&self) -> usize { + self.len() + } + + #[inline] + fn chunk_mut(&mut self) -> &mut UninitSlice { + // UninitSlice is repr(transparent), so safe to transmute + unsafe { &mut *(*self as *mut [u8] as *mut _) } + } + + #[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[..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(), val, cnt); + self.advance_mut(cnt); + } + } +} + +unsafe impl BufMut for Vec { + #[inline] + fn remaining_mut(&self) -> usize { + // A vector can never have more than isize::MAX bytes + core::isize::MAX as usize - self.len() + } + + #[inline] + unsafe fn advance_mut(&mut self, cnt: usize) { + let len = self.len(); + let remaining = self.capacity() - len; + + assert!( + cnt <= remaining, + "cannot advance past `remaining_mut`: {:?} <= {:?}", + cnt, + remaining + ); + + self.set_len(len + cnt); + } + + #[inline] + fn chunk_mut(&mut self) -> &mut UninitSlice { + if self.capacity() == self.len() { + self.reserve(64); // Grow the vec + } + + let cap = self.capacity(); + let len = self.len(); + + let ptr = self.as_mut_ptr(); + unsafe { &mut UninitSlice::from_raw_parts_mut(ptr, cap)[len..] } + } + + // Specialize these methods so they can skip checking `remaining_mut` + // and `advance_mut`. + fn put(&mut self, mut src: T) + where + Self: Sized, + { + // In case the src isn't contiguous, reserve upfront + self.reserve(src.remaining()); + + while src.has_remaining() { + let l; + + // a block to contain the src.bytes() borrow + { + let s = src.chunk(); + l = s.len(); + self.extend_from_slice(s); + } + + src.advance(l); + } + } + + #[inline] + 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 +// trait is "object-safe" or not. +fn _assert_trait_object(_b: &dyn BufMut) {} diff --git a/src/buf/chain.rs b/src/buf/chain.rs new file mode 100644 index 0000000..78979a1 --- /dev/null +++ b/src/buf/chain.rs @@ -0,0 +1,242 @@ +use crate::buf::{IntoIter, UninitSlice}; +use crate::{Buf, BufMut, Bytes}; + +#[cfg(feature = "std")] +use std::io::IoSlice; + +/// A `Chain` sequences two buffers. +/// +/// `Chain` is an adapter that links two underlying buffers and provides a +/// continuous view across both buffers. It is able to sequence either immutable +/// buffers ([`Buf`] values) or mutable buffers ([`BufMut`] values). +/// +/// This struct is generally created by calling [`Buf::chain`]. Please see that +/// function's documentation for more detail. +/// +/// # Examples +/// +/// ``` +/// use bytes::{Bytes, Buf}; +/// +/// let mut buf = (&b"hello "[..]) +/// .chain(&b"world"[..]); +/// +/// let full: Bytes = buf.copy_to_bytes(11); +/// assert_eq!(full[..], b"hello world"[..]); +/// ``` +/// +/// [`Buf::chain`]: trait.Buf.html#method.chain +/// [`Buf`]: trait.Buf.html +/// [`BufMut`]: trait.BufMut.html +#[derive(Debug)] +pub struct Chain { + a: T, + b: U, +} + +impl Chain { + /// Creates a new `Chain` sequencing the provided values. + pub(crate) fn new(a: T, b: U) -> Chain { + Chain { a, b } + } + + /// Gets a reference to the first underlying `Buf`. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let buf = (&b"hello"[..]) + /// .chain(&b"world"[..]); + /// + /// assert_eq!(buf.first_ref()[..], b"hello"[..]); + /// ``` + pub fn first_ref(&self) -> &T { + &self.a + } + + /// Gets a mutable reference to the first underlying `Buf`. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = (&b"hello"[..]) + /// .chain(&b"world"[..]); + /// + /// buf.first_mut().advance(1); + /// + /// let full = buf.copy_to_bytes(9); + /// assert_eq!(full, b"elloworld"[..]); + /// ``` + pub fn first_mut(&mut self) -> &mut T { + &mut self.a + } + + /// Gets a reference to the last underlying `Buf`. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let buf = (&b"hello"[..]) + /// .chain(&b"world"[..]); + /// + /// assert_eq!(buf.last_ref()[..], b"world"[..]); + /// ``` + pub fn last_ref(&self) -> &U { + &self.b + } + + /// Gets a mutable reference to the last underlying `Buf`. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = (&b"hello "[..]) + /// .chain(&b"world"[..]); + /// + /// buf.last_mut().advance(1); + /// + /// let full = buf.copy_to_bytes(10); + /// assert_eq!(full, b"hello orld"[..]); + /// ``` + pub fn last_mut(&mut self) -> &mut U { + &mut self.b + } + + /// Consumes this `Chain`, returning the underlying values. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let chain = (&b"hello"[..]) + /// .chain(&b"world"[..]); + /// + /// let (first, last) = chain.into_inner(); + /// assert_eq!(first[..], b"hello"[..]); + /// assert_eq!(last[..], b"world"[..]); + /// ``` + pub fn into_inner(self) -> (T, U) { + (self.a, self.b) + } +} + +impl Buf for Chain +where + T: Buf, + U: Buf, +{ + fn remaining(&self) -> usize { + self.a.remaining().checked_add(self.b.remaining()).unwrap() + } + + fn chunk(&self) -> &[u8] { + if self.a.has_remaining() { + self.a.chunk() + } else { + self.b.chunk() + } + } + + fn advance(&mut self, mut cnt: usize) { + let a_rem = self.a.remaining(); + + if a_rem != 0 { + if a_rem >= cnt { + self.a.advance(cnt); + return; + } + + // Consume what is left of a + self.a.advance(a_rem); + + cnt -= a_rem; + } + + self.b.advance(cnt); + } + + #[cfg(feature = "std")] + fn chunks_vectored<'a>(&'a self, dst: &mut [IoSlice<'a>]) -> usize { + let mut n = self.a.chunks_vectored(dst); + n += self.b.chunks_vectored(&mut dst[n..]); + n + } + + fn copy_to_bytes(&mut self, len: usize) -> Bytes { + let a_rem = self.a.remaining(); + if a_rem >= len { + self.a.copy_to_bytes(len) + } else if a_rem == 0 { + self.b.copy_to_bytes(len) + } else { + assert!( + len - a_rem <= self.b.remaining(), + "`len` greater than remaining" + ); + let mut ret = crate::BytesMut::with_capacity(len); + ret.put(&mut self.a); + ret.put((&mut self.b).take(len - a_rem)); + ret.freeze() + } + } +} + +unsafe impl BufMut for Chain +where + T: BufMut, + U: BufMut, +{ + fn remaining_mut(&self) -> usize { + self.a + .remaining_mut() + .saturating_add(self.b.remaining_mut()) + } + + fn chunk_mut(&mut self) -> &mut UninitSlice { + if self.a.has_remaining_mut() { + self.a.chunk_mut() + } else { + self.b.chunk_mut() + } + } + + unsafe fn advance_mut(&mut self, mut cnt: usize) { + let a_rem = self.a.remaining_mut(); + + if a_rem != 0 { + if a_rem >= cnt { + self.a.advance_mut(cnt); + return; + } + + // Consume what is left of a + self.a.advance_mut(a_rem); + + cnt -= a_rem; + } + + self.b.advance_mut(cnt); + } +} + +impl IntoIterator for Chain +where + T: Buf, + U: Buf, +{ + type Item = u8; + type IntoIter = IntoIter>; + + fn into_iter(self) -> Self::IntoIter { + IntoIter::new(self) + } +} diff --git a/src/buf/iter.rs b/src/buf/iter.rs new file mode 100644 index 0000000..c694e3d --- /dev/null +++ b/src/buf/iter.rs @@ -0,0 +1,130 @@ +use crate::Buf; + +/// Iterator over the bytes contained by the buffer. +/// +/// # Examples +/// +/// Basic usage: +/// +/// ``` +/// use bytes::Bytes; +/// +/// let buf = Bytes::from(&b"abc"[..]); +/// let mut iter = buf.into_iter(); +/// +/// assert_eq!(iter.next(), Some(b'a')); +/// assert_eq!(iter.next(), Some(b'b')); +/// assert_eq!(iter.next(), Some(b'c')); +/// assert_eq!(iter.next(), None); +/// ``` +/// +/// [`iter`]: trait.Buf.html#method.iter +/// [`Buf`]: trait.Buf.html +#[derive(Debug)] +pub struct IntoIter { + inner: T, +} + +impl IntoIter { + /// Creates an iterator over the bytes contained by the buffer. + /// + /// # Examples + /// + /// ``` + /// use bytes::Bytes; + /// + /// let buf = Bytes::from_static(b"abc"); + /// let mut iter = buf.into_iter(); + /// + /// assert_eq!(iter.next(), Some(b'a')); + /// assert_eq!(iter.next(), Some(b'b')); + /// assert_eq!(iter.next(), Some(b'c')); + /// assert_eq!(iter.next(), None); + /// ``` + pub fn new(inner: T) -> IntoIter { + IntoIter { inner } + } + + /// Consumes this `IntoIter`, returning the underlying value. + /// + /// # Examples + /// + /// ```rust + /// use bytes::{Buf, Bytes}; + /// + /// let buf = Bytes::from(&b"abc"[..]); + /// let mut iter = buf.into_iter(); + /// + /// assert_eq!(iter.next(), Some(b'a')); + /// + /// let buf = iter.into_inner(); + /// assert_eq!(2, buf.remaining()); + /// ``` + pub fn into_inner(self) -> T { + self.inner + } + + /// Gets a reference to the underlying `Buf`. + /// + /// It is inadvisable to directly read from the underlying `Buf`. + /// + /// # Examples + /// + /// ```rust + /// use bytes::{Buf, Bytes}; + /// + /// let buf = Bytes::from(&b"abc"[..]); + /// let mut iter = buf.into_iter(); + /// + /// assert_eq!(iter.next(), Some(b'a')); + /// + /// assert_eq!(2, iter.get_ref().remaining()); + /// ``` + pub fn get_ref(&self) -> &T { + &self.inner + } + + /// Gets a mutable reference to the underlying `Buf`. + /// + /// It is inadvisable to directly read from the underlying `Buf`. + /// + /// # Examples + /// + /// ```rust + /// use bytes::{Buf, BytesMut}; + /// + /// let buf = BytesMut::from(&b"abc"[..]); + /// let mut iter = buf.into_iter(); + /// + /// assert_eq!(iter.next(), Some(b'a')); + /// + /// iter.get_mut().advance(1); + /// + /// assert_eq!(iter.next(), Some(b'c')); + /// ``` + pub fn get_mut(&mut self) -> &mut T { + &mut self.inner + } +} + +impl Iterator for IntoIter { + type Item = u8; + + fn next(&mut self) -> Option { + if !self.inner.has_remaining() { + return None; + } + + let b = self.inner.chunk()[0]; + self.inner.advance(1); + + Some(b) + } + + fn size_hint(&self) -> (usize, Option) { + let rem = self.inner.remaining(); + (rem, Some(rem)) + } +} + +impl ExactSizeIterator for IntoIter {} diff --git a/src/buf/limit.rs b/src/buf/limit.rs new file mode 100644 index 0000000..b422be5 --- /dev/null +++ b/src/buf/limit.rs @@ -0,0 +1,75 @@ +use crate::buf::UninitSlice; +use crate::BufMut; + +use core::cmp; + +/// A `BufMut` adapter which limits the amount of bytes that can be written +/// to an underlying buffer. +#[derive(Debug)] +pub struct Limit { + inner: T, + limit: usize, +} + +pub(super) fn new(inner: T, limit: usize) -> Limit { + Limit { inner, limit } +} + +impl Limit { + /// Consumes this `Limit`, returning the underlying value. + pub fn into_inner(self) -> T { + self.inner + } + + /// Gets a reference to the underlying `BufMut`. + /// + /// It is inadvisable to directly write to the underlying `BufMut`. + pub fn get_ref(&self) -> &T { + &self.inner + } + + /// Gets a mutable reference to the underlying `BufMut`. + /// + /// It is inadvisable to directly write to the underlying `BufMut`. + pub fn get_mut(&mut self) -> &mut T { + &mut self.inner + } + + /// Returns the maximum number of bytes that can be written + /// + /// # Note + /// + /// If the inner `BufMut` has fewer bytes than indicated by this method then + /// that is the actual number of available bytes. + pub fn limit(&self) -> usize { + self.limit + } + + /// Sets the maximum number of bytes that can be written. + /// + /// # Note + /// + /// If the inner `BufMut` has fewer bytes than `lim` then that is the actual + /// number of available bytes. + pub fn set_limit(&mut self, lim: usize) { + self.limit = lim + } +} + +unsafe impl BufMut for Limit { + fn remaining_mut(&self) -> usize { + cmp::min(self.inner.remaining_mut(), self.limit) + } + + fn chunk_mut(&mut self) -> &mut UninitSlice { + let bytes = self.inner.chunk_mut(); + let end = cmp::min(bytes.len(), self.limit); + &mut bytes[..end] + } + + unsafe fn advance_mut(&mut self, cnt: usize) { + assert!(cnt <= self.limit); + self.inner.advance_mut(cnt); + self.limit -= cnt; + } +} diff --git a/src/buf/mod.rs b/src/buf/mod.rs new file mode 100644 index 0000000..c4c0a57 --- /dev/null +++ b/src/buf/mod.rs @@ -0,0 +1,41 @@ +//! Utilities for working with buffers. +//! +//! A buffer is any structure that contains a sequence of bytes. The bytes may +//! or may not be stored in contiguous memory. This module contains traits used +//! to abstract over buffers as well as utilities for working with buffer types. +//! +//! # `Buf`, `BufMut` +//! +//! These are the two foundational traits for abstractly working with buffers. +//! They can be thought as iterators for byte structures. They offer additional +//! performance over `Iterator` by providing an API optimized for byte slices. +//! +//! See [`Buf`] and [`BufMut`] for more details. +//! +//! [rope]: https://en.wikipedia.org/wiki/Rope_(data_structure) +//! [`Buf`]: trait.Buf.html +//! [`BufMut`]: trait.BufMut.html + +mod buf_impl; +mod buf_mut; +mod chain; +mod iter; +mod limit; +#[cfg(feature = "std")] +mod reader; +mod take; +mod uninit_slice; +mod vec_deque; +#[cfg(feature = "std")] +mod writer; + +pub use self::buf_impl::Buf; +pub use self::buf_mut::BufMut; +pub use self::chain::Chain; +pub use self::iter::IntoIter; +pub use self::limit::Limit; +pub use self::take::Take; +pub use self::uninit_slice::UninitSlice; + +#[cfg(feature = "std")] +pub use self::{reader::Reader, writer::Writer}; diff --git a/src/buf/reader.rs b/src/buf/reader.rs new file mode 100644 index 0000000..f2b4d98 --- /dev/null +++ b/src/buf/reader.rs @@ -0,0 +1,81 @@ +use crate::Buf; + +use std::{cmp, io}; + +/// A `Buf` adapter which implements `io::Read` for the inner value. +/// +/// This struct is generally created by calling `reader()` on `Buf`. See +/// documentation of [`reader()`](trait.Buf.html#method.reader) for more +/// details. +#[derive(Debug)] +pub struct Reader { + buf: B, +} + +pub fn new(buf: B) -> Reader { + Reader { buf } +} + +impl Reader { + /// Gets a reference to the underlying `Buf`. + /// + /// It is inadvisable to directly read from the underlying `Buf`. + /// + /// # Examples + /// + /// ```rust + /// use bytes::Buf; + /// + /// let buf = b"hello world".reader(); + /// + /// assert_eq!(b"hello world", buf.get_ref()); + /// ``` + pub fn get_ref(&self) -> &B { + &self.buf + } + + /// Gets a mutable reference to the underlying `Buf`. + /// + /// It is inadvisable to directly read from the underlying `Buf`. + pub fn get_mut(&mut self) -> &mut B { + &mut self.buf + } + + /// Consumes this `Reader`, returning the underlying value. + /// + /// # Examples + /// + /// ```rust + /// use bytes::Buf; + /// use std::io; + /// + /// let mut buf = b"hello world".reader(); + /// let mut dst = vec![]; + /// + /// io::copy(&mut buf, &mut dst).unwrap(); + /// + /// let buf = buf.into_inner(); + /// assert_eq!(0, buf.remaining()); + /// ``` + pub fn into_inner(self) -> B { + self.buf + } +} + +impl io::Read for Reader { + fn read(&mut self, dst: &mut [u8]) -> io::Result { + let len = cmp::min(self.buf.remaining(), dst.len()); + + Buf::copy_to_slice(&mut self.buf, &mut dst[0..len]); + Ok(len) + } +} + +impl io::BufRead for Reader { + fn fill_buf(&mut self) -> io::Result<&[u8]> { + Ok(self.buf.chunk()) + } + fn consume(&mut self, amt: usize) { + self.buf.advance(amt) + } +} diff --git a/src/buf/take.rs b/src/buf/take.rs new file mode 100644 index 0000000..d3cb10a --- /dev/null +++ b/src/buf/take.rs @@ -0,0 +1,155 @@ +use crate::{Buf, Bytes}; + +use core::cmp; + +/// A `Buf` adapter which limits the bytes read from an underlying buffer. +/// +/// This struct is generally created by calling `take()` on `Buf`. See +/// documentation of [`take()`](trait.Buf.html#method.take) for more details. +#[derive(Debug)] +pub struct Take { + inner: T, + limit: usize, +} + +pub fn new(inner: T, limit: usize) -> Take { + Take { inner, limit } +} + +impl Take { + /// Consumes this `Take`, returning the underlying value. + /// + /// # Examples + /// + /// ```rust + /// use bytes::{Buf, BufMut}; + /// + /// let mut buf = b"hello world".take(2); + /// let mut dst = vec![]; + /// + /// dst.put(&mut buf); + /// assert_eq!(*dst, b"he"[..]); + /// + /// let mut buf = buf.into_inner(); + /// + /// dst.clear(); + /// dst.put(&mut buf); + /// assert_eq!(*dst, b"llo world"[..]); + /// ``` + pub fn into_inner(self) -> T { + self.inner + } + + /// Gets a reference to the underlying `Buf`. + /// + /// It is inadvisable to directly read from the underlying `Buf`. + /// + /// # Examples + /// + /// ```rust + /// use bytes::Buf; + /// + /// let buf = b"hello world".take(2); + /// + /// assert_eq!(11, buf.get_ref().remaining()); + /// ``` + pub fn get_ref(&self) -> &T { + &self.inner + } + + /// Gets a mutable reference to the underlying `Buf`. + /// + /// It is inadvisable to directly read from the underlying `Buf`. + /// + /// # Examples + /// + /// ```rust + /// use bytes::{Buf, BufMut}; + /// + /// let mut buf = b"hello world".take(2); + /// let mut dst = vec![]; + /// + /// buf.get_mut().advance(2); + /// + /// dst.put(&mut buf); + /// assert_eq!(*dst, b"ll"[..]); + /// ``` + pub fn get_mut(&mut self) -> &mut T { + &mut self.inner + } + + /// Returns the maximum number of bytes that can be read. + /// + /// # Note + /// + /// If the inner `Buf` has fewer bytes than indicated by this method then + /// that is the actual number of available bytes. + /// + /// # Examples + /// + /// ```rust + /// use bytes::Buf; + /// + /// let mut buf = b"hello world".take(2); + /// + /// assert_eq!(2, buf.limit()); + /// assert_eq!(b'h', buf.get_u8()); + /// assert_eq!(1, buf.limit()); + /// ``` + pub fn limit(&self) -> usize { + self.limit + } + + /// Sets the maximum number of bytes that can be read. + /// + /// # Note + /// + /// If the inner `Buf` has fewer bytes than `lim` then that is the actual + /// number of available bytes. + /// + /// # Examples + /// + /// ```rust + /// use bytes::{Buf, BufMut}; + /// + /// let mut buf = b"hello world".take(2); + /// let mut dst = vec![]; + /// + /// dst.put(&mut buf); + /// assert_eq!(*dst, b"he"[..]); + /// + /// dst.clear(); + /// + /// buf.set_limit(3); + /// dst.put(&mut buf); + /// assert_eq!(*dst, b"llo"[..]); + /// ``` + pub fn set_limit(&mut self, lim: usize) { + self.limit = lim + } +} + +impl Buf for Take { + fn remaining(&self) -> usize { + cmp::min(self.inner.remaining(), self.limit) + } + + fn chunk(&self) -> &[u8] { + let bytes = self.inner.chunk(); + &bytes[..cmp::min(bytes.len(), self.limit)] + } + + fn advance(&mut self, cnt: usize) { + assert!(cnt <= self.limit); + self.inner.advance(cnt); + self.limit -= cnt; + } + + fn copy_to_bytes(&mut self, len: usize) -> Bytes { + assert!(len <= self.remaining(), "`len` greater than remaining"); + + let r = self.inner.copy_to_bytes(len); + self.limit -= len; + r + } +} diff --git a/src/buf/uninit_slice.rs b/src/buf/uninit_slice.rs new file mode 100644 index 0000000..3161a14 --- /dev/null +++ b/src/buf/uninit_slice.rs @@ -0,0 +1,213 @@ +use core::fmt; +use core::mem::MaybeUninit; +use core::ops::{ + Index, IndexMut, Range, RangeFrom, RangeFull, RangeInclusive, RangeTo, RangeToInclusive, +}; + +/// Uninitialized byte slice. +/// +/// Returned by `BufMut::chunk_mut()`, the referenced byte slice may be +/// uninitialized. The wrapper provides safe access without introducing +/// undefined behavior. +/// +/// The safety invariants of this wrapper are: +/// +/// 1. Reading from an `UninitSlice` is undefined behavior. +/// 2. Writing uninitialized bytes to an `UninitSlice` is undefined behavior. +/// +/// The difference between `&mut UninitSlice` and `&mut [MaybeUninit]` is +/// that it is possible in safe code to write uninitialized bytes to an +/// `&mut [MaybeUninit]`, which this type prohibits. +#[repr(transparent)] +pub struct UninitSlice([MaybeUninit]); + +impl UninitSlice { + pub(crate) fn from_slice(slice: &mut [MaybeUninit]) -> &mut UninitSlice { + unsafe { &mut *(slice as *mut [MaybeUninit] as *mut UninitSlice) } + } + + /// Create a `&mut UninitSlice` from a pointer and a length. + /// + /// # Safety + /// + /// The caller must ensure that `ptr` references a valid memory region owned + /// by the caller representing a byte slice for the duration of `'a`. + /// + /// # Examples + /// + /// ``` + /// use bytes::buf::UninitSlice; + /// + /// let bytes = b"hello world".to_vec(); + /// let ptr = bytes.as_ptr() as *mut _; + /// let len = bytes.len(); + /// + /// let slice = unsafe { UninitSlice::from_raw_parts_mut(ptr, len) }; + /// ``` + #[inline] + 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); + Self::from_slice(maybe_init) + } + + /// Write a single byte at the specified offset. + /// + /// # Panics + /// + /// The function panics if `index` is out of bounds. + /// + /// # Examples + /// + /// ``` + /// use bytes::buf::UninitSlice; + /// + /// let mut data = [b'f', b'o', b'o']; + /// let slice = unsafe { UninitSlice::from_raw_parts_mut(data.as_mut_ptr(), 3) }; + /// + /// slice.write_byte(0, b'b'); + /// + /// assert_eq!(b"boo", &data[..]); + /// ``` + #[inline] + pub fn write_byte(&mut self, index: usize, byte: u8) { + assert!(index < self.len()); + + unsafe { self[index..].as_mut_ptr().write(byte) } + } + + /// Copies bytes from `src` into `self`. + /// + /// The length of `src` must be the same as `self`. + /// + /// # Panics + /// + /// The function panics if `src` has a different length than `self`. + /// + /// # Examples + /// + /// ``` + /// use bytes::buf::UninitSlice; + /// + /// let mut data = [b'f', b'o', b'o']; + /// let slice = unsafe { UninitSlice::from_raw_parts_mut(data.as_mut_ptr(), 3) }; + /// + /// slice.copy_from_slice(b"bar"); + /// + /// assert_eq!(b"bar", &data[..]); + /// ``` + #[inline] + pub fn copy_from_slice(&mut self, src: &[u8]) { + use core::ptr; + + assert_eq!(self.len(), src.len()); + + unsafe { + ptr::copy_nonoverlapping(src.as_ptr(), self.as_mut_ptr(), self.len()); + } + } + + /// Return a raw pointer to the slice's buffer. + /// + /// # Safety + /// + /// The caller **must not** read from the referenced memory and **must not** + /// write **uninitialized** bytes to the slice either. + /// + /// # Examples + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut data = [0, 1, 2]; + /// let mut slice = &mut data[..]; + /// let ptr = BufMut::chunk_mut(&mut slice).as_mut_ptr(); + /// ``` + #[inline] + pub fn as_mut_ptr(&mut self) -> *mut u8 { + 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 + /// + /// ``` + /// use bytes::BufMut; + /// + /// let mut data = [0, 1, 2]; + /// let mut slice = &mut data[..]; + /// let len = BufMut::chunk_mut(&mut slice).len(); + /// + /// assert_eq!(len, 3); + /// ``` + #[inline] + pub fn len(&self) -> usize { + self.0.len() + } +} + +impl fmt::Debug for UninitSlice { + fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { + fmt.debug_struct("UninitSlice[...]").finish() + } +} + +macro_rules! impl_index { + ($($t:ty),*) => { + $( + impl Index<$t> for UninitSlice { + type Output = UninitSlice; + + #[inline] + fn index(&self, index: $t) -> &UninitSlice { + let maybe_uninit: &[MaybeUninit] = &self.0[index]; + unsafe { &*(maybe_uninit as *const [MaybeUninit] as *const UninitSlice) } + } + } + + impl IndexMut<$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) } + } + } + )* + }; +} + +impl_index!( + Range, + RangeFrom, + RangeFull, + RangeInclusive, + RangeTo, + RangeToInclusive +); diff --git a/src/buf/vec_deque.rs b/src/buf/vec_deque.rs new file mode 100644 index 0000000..263167e --- /dev/null +++ b/src/buf/vec_deque.rs @@ -0,0 +1,22 @@ +use alloc::collections::VecDeque; + +use super::Buf; + +impl Buf for VecDeque { + fn remaining(&self) -> usize { + self.len() + } + + fn chunk(&self) -> &[u8] { + let (s1, s2) = self.as_slices(); + if s1.is_empty() { + s2 + } else { + s1 + } + } + + fn advance(&mut self, cnt: usize) { + self.drain(..cnt); + } +} diff --git a/src/buf/writer.rs b/src/buf/writer.rs new file mode 100644 index 0000000..261d7cd --- /dev/null +++ b/src/buf/writer.rs @@ -0,0 +1,88 @@ +use crate::BufMut; + +use std::{cmp, io}; + +/// A `BufMut` adapter which implements `io::Write` for the inner value. +/// +/// This struct is generally created by calling `writer()` on `BufMut`. See +/// documentation of [`writer()`](trait.BufMut.html#method.writer) for more +/// details. +#[derive(Debug)] +pub struct Writer { + buf: B, +} + +pub fn new(buf: B) -> Writer { + Writer { buf } +} + +impl Writer { + /// Gets a reference to the underlying `BufMut`. + /// + /// It is inadvisable to directly write to the underlying `BufMut`. + /// + /// # Examples + /// + /// ```rust + /// use bytes::BufMut; + /// + /// let buf = Vec::with_capacity(1024).writer(); + /// + /// assert_eq!(1024, buf.get_ref().capacity()); + /// ``` + pub fn get_ref(&self) -> &B { + &self.buf + } + + /// Gets a mutable reference to the underlying `BufMut`. + /// + /// It is inadvisable to directly write to the underlying `BufMut`. + /// + /// # Examples + /// + /// ```rust + /// use bytes::BufMut; + /// + /// let mut buf = vec![].writer(); + /// + /// buf.get_mut().reserve(1024); + /// + /// assert_eq!(1024, buf.get_ref().capacity()); + /// ``` + pub fn get_mut(&mut self) -> &mut B { + &mut self.buf + } + + /// Consumes this `Writer`, returning the underlying value. + /// + /// # Examples + /// + /// ```rust + /// use bytes::BufMut; + /// use std::io; + /// + /// let mut buf = vec![].writer(); + /// let mut src = &b"hello world"[..]; + /// + /// io::copy(&mut src, &mut buf).unwrap(); + /// + /// let buf = buf.into_inner(); + /// assert_eq!(*buf, b"hello world"[..]); + /// ``` + pub fn into_inner(self) -> B { + self.buf + } +} + +impl io::Write for Writer { + fn write(&mut self, src: &[u8]) -> io::Result { + let n = cmp::min(self.buf.remaining_mut(), src.len()); + + self.buf.put(&src[0..n]); + Ok(n) + } + + fn flush(&mut self) -> io::Result<()> { + Ok(()) + } +} diff --git a/src/bytes.rs b/src/bytes.rs new file mode 100644 index 0000000..0404a72 --- /dev/null +++ b/src/bytes.rs @@ -0,0 +1,1304 @@ +use core::iter::FromIterator; +use core::ops::{Deref, RangeBounds}; +use core::{cmp, fmt, hash, mem, ptr, slice, usize}; + +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::{AtomicPtr, AtomicUsize, Ordering}; +use crate::Buf; + +/// A cheaply cloneable and sliceable chunk of contiguous memory. +/// +/// `Bytes` is an efficient container for storing and operating on contiguous +/// slices of memory. It is intended for use primarily in networking code, but +/// could have applications elsewhere as well. +/// +/// `Bytes` values facilitate zero-copy network programming by allowing multiple +/// `Bytes` objects to point to the same underlying memory. +/// +/// `Bytes` does not have a single implementation. It is an interface, whose +/// exact behavior is implemented through dynamic dispatch in several underlying +/// implementations of `Bytes`. +/// +/// 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 original buffer. +/// +/// ``` +/// use bytes::Bytes; +/// +/// let mut mem = Bytes::from("Hello world"); +/// let a = mem.slice(0..5); +/// +/// assert_eq!(a, "Hello"); +/// +/// let b = mem.split_to(6); +/// +/// assert_eq!(mem, "world"); +/// assert_eq!(b, "Hello "); +/// ``` +/// +/// # Memory layout +/// +/// The `Bytes` struct itself is fairly small, limited to 4 `usize` fields used +/// to track information about which segment of the underlying memory the +/// `Bytes` handle has access to. +/// +/// `Bytes` keeps both a pointer to the shared state containing the full memory +/// slice and a pointer to the start of the region visible by the handle. +/// `Bytes` also tracks the length of its view into the memory. +/// +/// # Sharing +/// +/// `Bytes` contains a vtable, which allows implementations of `Bytes` to define +/// 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. +/// +/// For `Bytes` implementations which refer to constant memory (e.g. created +/// via `Bytes::from_static()`) the cloning implementation will be a no-op. +/// +/// For `Bytes` implementations which point to a reference counted shared storage +/// (e.g. an `Arc<[u8]>`), sharing will be implemented by increasing the +/// reference count. +/// +/// Due to this mechanism, multiple `Bytes` instances may point to the same +/// shared memory region. +/// Each `Bytes` instance can point to different sections within that +/// memory region, and `Bytes` instances may or may not have overlapping views +/// into the memory. +/// +/// The following diagram visualizes a scenario where 2 `Bytes` instances make +/// use of an `Arc`-based backing storage, and provide access to different views: +/// +/// ```text +/// +/// Arc ptrs ┌─────────┐ +/// ________________________ / │ Bytes 2 │ +/// / └─────────┘ +/// / ┌───────────┐ | | +/// |_________/ │ Bytes 1 │ | | +/// | └───────────┘ | | +/// | | | ___/ data | tail +/// | data | tail |/ | +/// v v v v +/// ┌─────┬─────┬───────────┬───────────────┬─────┐ +/// │ Arc │ │ │ │ │ +/// └─────┴─────┴───────────┴───────────────┴─────┘ +/// ``` +pub struct Bytes { + ptr: *const u8, + len: usize, + // inlined "trait object" + data: AtomicPtr<()>, + vtable: &'static Vtable, +} + +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), +} + +impl Bytes { + /// Creates a new empty `Bytes`. + /// + /// This will not allocate and the returned `Bytes` handle will be empty. + /// + /// # Examples + /// + /// ``` + /// use bytes::Bytes; + /// + /// let b = Bytes::new(); + /// assert_eq!(&b[..], b""); + /// ``` + #[inline] + #[cfg(not(all(loom, test)))] + pub const fn new() -> Self { + // Make it a named const to work around + // "unsizing casts are not allowed in const fn" + const EMPTY: &[u8] = &[]; + Bytes::from_static(EMPTY) + } + + #[cfg(all(loom, test))] + pub fn new() -> Self { + const EMPTY: &[u8] = &[]; + Bytes::from_static(EMPTY) + } + + /// Creates a new `Bytes` from a static slice. + /// + /// The returned `Bytes` will point directly to the static slice. There is + /// no allocating or copying. + /// + /// # Examples + /// + /// ``` + /// use bytes::Bytes; + /// + /// let b = Bytes::from_static(b"hello"); + /// assert_eq!(&b[..], b"hello"); + /// ``` + #[inline] + #[cfg(not(all(loom, test)))] + pub const fn from_static(bytes: &'static [u8]) -> Self { + Bytes { + ptr: bytes.as_ptr(), + len: bytes.len(), + data: AtomicPtr::new(ptr::null_mut()), + vtable: &STATIC_VTABLE, + } + } + + #[cfg(all(loom, test))] + pub fn from_static(bytes: &'static [u8]) -> Self { + Bytes { + ptr: bytes.as_ptr(), + len: bytes.len(), + data: AtomicPtr::new(ptr::null_mut()), + vtable: &STATIC_VTABLE, + } + } + + /// Returns the number of bytes contained in this `Bytes`. + /// + /// # Examples + /// + /// ``` + /// use bytes::Bytes; + /// + /// let b = Bytes::from(&b"hello"[..]); + /// assert_eq!(b.len(), 5); + /// ``` + #[inline] + pub const fn len(&self) -> usize { + self.len + } + + /// Returns true if the `Bytes` has a length of 0. + /// + /// # Examples + /// + /// ``` + /// use bytes::Bytes; + /// + /// let b = Bytes::new(); + /// assert!(b.is_empty()); + /// ``` + #[inline] + pub const fn is_empty(&self) -> bool { + self.len == 0 + } + + /// Creates `Bytes` instance from slice, by copying it. + pub fn copy_from_slice(data: &[u8]) -> Self { + data.to_vec().into() + } + + /// Returns a slice of self for the provided range. + /// + /// This will increment the reference count for the underlying memory and + /// return a new `Bytes` handle set to the slice. + /// + /// This operation is `O(1)`. + /// + /// # Examples + /// + /// ``` + /// use bytes::Bytes; + /// + /// let a = Bytes::from(&b"hello world"[..]); + /// let b = a.slice(2..5); + /// + /// assert_eq!(&b[..], b"llo"); + /// ``` + /// + /// # Panics + /// + /// Requires that `begin <= end` and `end <= self.len()`, otherwise slicing + /// will panic. + pub fn slice(&self, range: impl RangeBounds) -> Self { + use core::ops::Bound; + + let len = self.len(); + + let begin = match range.start_bound() { + Bound::Included(&n) => n, + Bound::Excluded(&n) => n + 1, + Bound::Unbounded => 0, + }; + + let end = match range.end_bound() { + Bound::Included(&n) => n.checked_add(1).expect("out of range"), + Bound::Excluded(&n) => n, + Bound::Unbounded => len, + }; + + assert!( + begin <= end, + "range start must not be greater than end: {:?} <= {:?}", + begin, + end, + ); + assert!( + end <= len, + "range end out of bounds: {:?} <= {:?}", + end, + len, + ); + + if end == begin { + return Bytes::new(); + } + + let mut ret = self.clone(); + + ret.len = end - begin; + ret.ptr = unsafe { ret.ptr.add(begin) }; + + ret + } + + /// Returns a slice of self that is equivalent to the given `subset`. + /// + /// When processing a `Bytes` buffer with other tools, one often gets a + /// `&[u8]` which is in fact a slice of the `Bytes`, i.e. a subset of it. + /// This function turns that `&[u8]` into another `Bytes`, as if one had + /// called `self.slice()` with the offsets that correspond to `subset`. + /// + /// This operation is `O(1)`. + /// + /// # Examples + /// + /// ``` + /// use bytes::Bytes; + /// + /// let bytes = Bytes::from(&b"012345678"[..]); + /// let as_slice = bytes.as_ref(); + /// let subset = &as_slice[2..6]; + /// let subslice = bytes.slice_ref(&subset); + /// assert_eq!(&subslice[..], b"2345"); + /// ``` + /// + /// # Panics + /// + /// 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]) -> 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() { + return Bytes::new(); + } + + let bytes_p = self.as_ptr() as usize; + let bytes_len = self.len(); + + let sub_p = subset.as_ptr() as usize; + let sub_len = subset.len(); + + assert!( + sub_p >= bytes_p, + "subset pointer ({:p}) is smaller than self pointer ({:p})", + subset.as_ptr(), + self.as_ptr(), + ); + assert!( + sub_p + sub_len <= bytes_p + bytes_len, + "subset is out of bounds: self = ({:p}, {}), subset = ({:p}, {})", + self.as_ptr(), + bytes_len, + subset.as_ptr(), + sub_len, + ); + + let sub_offset = sub_p - bytes_p; + + self.slice(sub_offset..(sub_offset + sub_len)) + } + + /// Splits the bytes into two at the given index. + /// + /// Afterwards `self` contains elements `[0, at)`, and the returned `Bytes` + /// contains elements `[at, len)`. + /// + /// This is an `O(1)` operation that just increases the reference count and + /// sets a few indices. + /// + /// # Examples + /// + /// ``` + /// use bytes::Bytes; + /// + /// let mut a = Bytes::from(&b"hello world"[..]); + /// let b = a.split_off(5); + /// + /// assert_eq!(&a[..], b"hello"); + /// assert_eq!(&b[..], b" world"); + /// ``` + /// + /// # Panics + /// + /// 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) -> Self { + assert!( + at <= self.len(), + "split_off out of bounds: {:?} <= {:?}", + at, + self.len(), + ); + + if at == self.len() { + return Bytes::new(); + } + + if at == 0 { + return mem::replace(self, Bytes::new()); + } + + let mut ret = self.clone(); + + self.len = at; + + unsafe { ret.inc_start(at) }; + + ret + } + + /// Splits the bytes into two at the given index. + /// + /// Afterwards `self` contains elements `[at, len)`, and the returned + /// `Bytes` contains elements `[0, at)`. + /// + /// This is an `O(1)` operation that just increases the reference count and + /// sets a few indices. + /// + /// # Examples + /// + /// ``` + /// use bytes::Bytes; + /// + /// let mut a = Bytes::from(&b"hello world"[..]); + /// let b = a.split_to(5); + /// + /// assert_eq!(&a[..], b" world"); + /// assert_eq!(&b[..], b"hello"); + /// ``` + /// + /// # Panics + /// + /// 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) -> Self { + assert!( + at <= self.len(), + "split_to out of bounds: {:?} <= {:?}", + at, + self.len(), + ); + + if at == self.len() { + return mem::replace(self, Bytes::new()); + } + + if at == 0 { + return Bytes::new(); + } + + let mut ret = self.clone(); + + unsafe { self.inc_start(at) }; + + ret.len = at; + ret + } + + /// Shortens the buffer, keeping the first `len` bytes and dropping the + /// rest. + /// + /// If `len` is greater than the buffer's current length, this has no + /// effect. + /// + /// The [`split_off`] method can emulate `truncate`, but this causes the + /// excess bytes to be returned instead of dropped. + /// + /// # Examples + /// + /// ``` + /// use bytes::Bytes; + /// + /// let mut buf = Bytes::from(&b"hello world"[..]); + /// buf.truncate(5); + /// assert_eq!(buf, b"hello"[..]); + /// ``` + /// + /// [`split_off`]: #method.split_off + #[inline] + pub fn truncate(&mut self, len: usize) { + if len < self.len { + // The Vec "promotable" vtables do not store the capacity, + // so we cannot truncate while using this repr. We *have* to + // promote using `split_off` so the capacity can be stored. + if self.vtable as *const Vtable == &PROMOTABLE_EVEN_VTABLE + || self.vtable as *const Vtable == &PROMOTABLE_ODD_VTABLE + { + drop(self.split_off(len)); + } else { + self.len = len; + } + } + } + + /// Clears the buffer, removing all data. + /// + /// # Examples + /// + /// ``` + /// use bytes::Bytes; + /// + /// let mut buf = Bytes::from(&b"hello world"[..]); + /// buf.clear(); + /// assert!(buf.is_empty()); + /// ``` + #[inline] + pub fn clear(&mut self) { + self.truncate(0); + } + + #[inline] + pub(crate) unsafe fn with_vtable( + ptr: *const u8, + len: usize, + data: AtomicPtr<()>, + vtable: &'static Vtable, + ) -> Bytes { + Bytes { + ptr, + len, + data, + vtable, + } + } + + // private + + #[inline] + fn as_slice(&self) -> &[u8] { + unsafe { slice::from_raw_parts(self.ptr, self.len) } + } + + #[inline] + unsafe fn inc_start(&mut self, by: usize) { + // 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.add(by); + } +} + +// Vtable must enforce this behavior +unsafe impl Send for Bytes {} +unsafe impl Sync for Bytes {} + +impl Drop for Bytes { + #[inline] + fn drop(&mut self) { + unsafe { (self.vtable.drop)(&mut self.data, self.ptr, self.len) } + } +} + +impl Clone for Bytes { + #[inline] + fn clone(&self) -> Bytes { + unsafe { (self.vtable.clone)(&self.data, self.ptr, self.len) } + } +} + +impl Buf for Bytes { + #[inline] + fn remaining(&self) -> usize { + self.len() + } + + #[inline] + fn chunk(&self) -> &[u8] { + self.as_slice() + } + + #[inline] + fn advance(&mut self, cnt: usize) { + assert!( + cnt <= self.len(), + "cannot advance past `remaining`: {:?} <= {:?}", + cnt, + self.len(), + ); + + unsafe { + self.inc_start(cnt); + } + } + + fn copy_to_bytes(&mut self, len: usize) -> crate::Bytes { + if len == self.remaining() { + core::mem::replace(self, Bytes::new()) + } else { + let ret = self.slice(..len); + self.advance(len); + ret + } + } +} + +impl Deref for Bytes { + type Target = [u8]; + + #[inline] + fn deref(&self) -> &[u8] { + self.as_slice() + } +} + +impl AsRef<[u8]> for Bytes { + #[inline] + fn as_ref(&self) -> &[u8] { + self.as_slice() + } +} + +impl hash::Hash for Bytes { + fn hash(&self, state: &mut H) + where + H: hash::Hasher, + { + self.as_slice().hash(state); + } +} + +impl Borrow<[u8]> for Bytes { + fn borrow(&self) -> &[u8] { + self.as_slice() + } +} + +impl IntoIterator for Bytes { + type Item = u8; + type IntoIter = IntoIter; + + fn into_iter(self) -> Self::IntoIter { + IntoIter::new(self) + } +} + +impl<'a> IntoIterator for &'a Bytes { + type Item = &'a u8; + type IntoIter = core::slice::Iter<'a, u8>; + + fn into_iter(self) -> Self::IntoIter { + self.as_slice().iter() + } +} + +impl FromIterator for Bytes { + fn from_iter>(into_iter: T) -> Self { + Vec::from_iter(into_iter).into() + } +} + +// impl Eq + +impl PartialEq for Bytes { + fn eq(&self, other: &Bytes) -> bool { + self.as_slice() == other.as_slice() + } +} + +impl PartialOrd for Bytes { + fn partial_cmp(&self, other: &Bytes) -> Option { + self.as_slice().partial_cmp(other.as_slice()) + } +} + +impl Ord for Bytes { + fn cmp(&self, other: &Bytes) -> cmp::Ordering { + self.as_slice().cmp(other.as_slice()) + } +} + +impl Eq for Bytes {} + +impl PartialEq<[u8]> for Bytes { + fn eq(&self, other: &[u8]) -> bool { + self.as_slice() == other + } +} + +impl PartialOrd<[u8]> for Bytes { + fn partial_cmp(&self, other: &[u8]) -> Option { + self.as_slice().partial_cmp(other) + } +} + +impl PartialEq for [u8] { + fn eq(&self, other: &Bytes) -> bool { + *other == *self + } +} + +impl PartialOrd for [u8] { + fn partial_cmp(&self, other: &Bytes) -> Option { + <[u8] as PartialOrd<[u8]>>::partial_cmp(self, other) + } +} + +impl PartialEq for Bytes { + fn eq(&self, other: &str) -> bool { + self.as_slice() == other.as_bytes() + } +} + +impl PartialOrd for Bytes { + fn partial_cmp(&self, other: &str) -> Option { + self.as_slice().partial_cmp(other.as_bytes()) + } +} + +impl PartialEq for str { + fn eq(&self, other: &Bytes) -> bool { + *other == *self + } +} + +impl PartialOrd for str { + fn partial_cmp(&self, other: &Bytes) -> Option { + <[u8] as PartialOrd<[u8]>>::partial_cmp(self.as_bytes(), other) + } +} + +impl PartialEq> for Bytes { + fn eq(&self, other: &Vec) -> bool { + *self == other[..] + } +} + +impl PartialOrd> for Bytes { + fn partial_cmp(&self, other: &Vec) -> Option { + self.as_slice().partial_cmp(&other[..]) + } +} + +impl PartialEq for Vec { + fn eq(&self, other: &Bytes) -> bool { + *other == *self + } +} + +impl PartialOrd for Vec { + fn partial_cmp(&self, other: &Bytes) -> Option { + <[u8] as PartialOrd<[u8]>>::partial_cmp(self, other) + } +} + +impl PartialEq for Bytes { + fn eq(&self, other: &String) -> bool { + *self == other[..] + } +} + +impl PartialOrd for Bytes { + fn partial_cmp(&self, other: &String) -> Option { + self.as_slice().partial_cmp(other.as_bytes()) + } +} + +impl PartialEq for String { + fn eq(&self, other: &Bytes) -> bool { + *other == *self + } +} + +impl PartialOrd for String { + fn partial_cmp(&self, other: &Bytes) -> Option { + <[u8] as PartialOrd<[u8]>>::partial_cmp(self.as_bytes(), other) + } +} + +impl PartialEq for &[u8] { + fn eq(&self, other: &Bytes) -> bool { + *other == *self + } +} + +impl PartialOrd for &[u8] { + fn partial_cmp(&self, other: &Bytes) -> Option { + <[u8] as PartialOrd<[u8]>>::partial_cmp(self, other) + } +} + +impl PartialEq for &str { + fn eq(&self, other: &Bytes) -> bool { + *other == *self + } +} + +impl PartialOrd for &str { + fn partial_cmp(&self, other: &Bytes) -> Option { + <[u8] as PartialOrd<[u8]>>::partial_cmp(self.as_bytes(), other) + } +} + +impl<'a, T: ?Sized> PartialEq<&'a T> for Bytes +where + Bytes: PartialEq, +{ + fn eq(&self, other: &&'a T) -> bool { + *self == **other + } +} + +impl<'a, T: ?Sized> PartialOrd<&'a T> for Bytes +where + Bytes: PartialOrd, +{ + fn partial_cmp(&self, other: &&'a T) -> Option { + self.partial_cmp(&**other) + } +} + +// impl From + +impl Default for Bytes { + #[inline] + fn default() -> Bytes { + Bytes::new() + } +} + +impl From<&'static [u8]> for Bytes { + fn from(slice: &'static [u8]) -> Bytes { + Bytes::from_static(slice) + } +} + +impl From<&'static str> for Bytes { + fn from(slice: &'static str) -> Bytes { + Bytes::from_static(slice.as_bytes()) + } +} + +impl From> for Bytes { + fn from(vec: Vec) -> Bytes { + 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 slice.is_empty() { + return Bytes::new(); + } + + let len = slice.len(); + let ptr = Box::into_raw(slice) as *mut u8; + + if ptr as usize & 0x1 == 0 { + let data = ptr_map(ptr, |addr| addr | KIND_VEC); + Bytes { + ptr, + len, + data: AtomicPtr::new(data.cast()), + vtable: &PROMOTABLE_EVEN_VTABLE, + } + } else { + Bytes { + ptr, + len, + data: AtomicPtr::new(ptr.cast()), + vtable: &PROMOTABLE_ODD_VTABLE, + } + } + } +} + +impl From for Bytes { + fn from(s: String) -> Bytes { + Bytes::from(s.into_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 { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.debug_struct("Vtable") + .field("clone", &(self.clone as *const ())) + .field("drop", &(self.drop as *const ())) + .finish() + } +} + +// ===== impl StaticVtable ===== + +const STATIC_VTABLE: Vtable = Vtable { + clone: static_clone, + to_vec: static_to_vec, + drop: static_drop, +}; + +unsafe fn static_clone(_: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Bytes { + let slice = slice::from_raw_parts(ptr, len); + 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] +} + +// ===== impl PromotableVtable ===== + +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, +}; + +unsafe fn promotable_even_clone(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Bytes { + let shared = data.load(Ordering::Acquire); + let kind = shared as usize & KIND_MASK; + + if kind == KIND_ARC { + shallow_clone_arc(shared.cast(), ptr, len) + } else { + debug_assert_eq!(kind, KIND_VEC); + 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.cast()); + } else { + debug_assert_eq!(kind, KIND_VEC); + let buf = ptr_map(shared.cast(), |addr| addr & !KIND_MASK); + free_boxed_slice(buf, ptr, len); + } + }); +} + +unsafe fn promotable_odd_clone(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Bytes { + let shared = data.load(Ordering::Acquire); + let kind = shared as usize & KIND_MASK; + + if kind == KIND_ARC { + shallow_clone_arc(shared as _, ptr, len) + } else { + debug_assert_eq!(kind, KIND_VEC); + 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.cast()); + } else { + debug_assert_eq!(kind, KIND_VEC); + + free_boxed_slice(shared.cast(), ptr, len); + } + }); +} + +unsafe fn free_boxed_slice(buf: *mut u8, offset: *const u8, len: usize) { + let cap = (offset as usize - buf as usize) + len; + dealloc(buf, Layout::from_size_align(cap, 1).unwrap()) +} + +// ===== impl SharedVtable ===== + +struct Shared { + // 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. +// This flag is set when the LSB is 0. +const _: [(); 0 - mem::align_of::() % 2] = []; // Assert that the alignment of `Shared` is divisible by 2. + +static SHARED_VTABLE: Vtable = Vtable { + clone: shared_clone, + to_vec: shared_to_vec, + drop: shared_drop, +}; + +const KIND_ARC: usize = 0b0; +const KIND_VEC: usize = 0b1; +const KIND_MASK: usize = 0b1; + +unsafe fn shared_clone(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Bytes { + let shared = data.load(Ordering::Relaxed); + 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.cast()); + }); +} + +unsafe fn shallow_clone_arc(shared: *mut Shared, ptr: *const u8, len: usize) -> Bytes { + let old_size = (*shared).ref_cnt.fetch_add(1, Ordering::Relaxed); + + if old_size > usize::MAX >> 1 { + crate::abort(); + } + + Bytes { + ptr, + len, + data: AtomicPtr::new(shared as _), + vtable: &SHARED_VTABLE, + } +} + +#[cold] +unsafe fn shallow_clone_vec( + atom: &AtomicPtr<()>, + ptr: *const (), + buf: *mut u8, + offset: *const u8, + len: usize, +) -> Bytes { + // If the buffer is still tracked in a `Vec`. It is time to + // promote the vec to an `Arc`. This could potentially be called + // concurrently, so some care must be taken. + + // First, allocate a new `Shared` instance containing the + // `Vec` fields. It's important to note that `ptr`, `len`, + // and `cap` cannot be mutated without having `&mut self`. + // This means that these fields will not be concurrently + // updated and since the buffer hasn't been promoted to an + // `Arc`, those three fields still are the components of the + // vector. + let shared = Box::new(Shared { + 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`. + ref_cnt: AtomicUsize::new(2), + }); + + 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", + ); + + // Try compare & swapping the pointer into the `arc` field. + // `Release` is used synchronize with other threads that + // will load the `arc` field. + // + // If the `compare_exchange` fails, then the thread lost the + // race to promote the buffer to shared. The `Acquire` + // ordering will synchronize with the `compare_exchange` + // that happened in the other thread and the `Shared` + // pointed to by `actual` will be visible. + match atom.compare_exchange(ptr as _, shared as _, Ordering::AcqRel, Ordering::Acquire) { + Ok(actual) => { + debug_assert!(actual as usize == ptr as usize); + // The upgrade was successful, the new handle can be + // returned. + Bytes { + ptr: offset, + len, + data: AtomicPtr::new(shared as _), + vtable: &SHARED_VTABLE, + } + } + Err(actual) => { + // The upgrade failed, a concurrent clone happened. Release + // the allocation that was made in this thread, it will not + // be needed. + let shared = Box::from_raw(shared); + mem::forget(*shared); + + // Buffer already promoted to shared storage, so increment ref + // count. + shallow_clone_arc(actual as _, offset, len) + } + } +} + +unsafe fn release_shared(ptr: *mut Shared) { + // `Shared` storage... follow the drop steps from Arc. + if (*ptr).ref_cnt.fetch_sub(1, Ordering::Release) != 1 { + return; + } + + // This fence is needed to prevent reordering of use of the data and + // deletion of the data. Because it is marked `Release`, the decreasing + // of the reference count synchronizes with this `Acquire` fence. This + // means that use of the data happens before decreasing the reference + // count, which happens before this fence, which happens before the + // deletion of the data. + // + // As explained in the [Boost documentation][1], + // + // > It is important to enforce any possible access to the object in one + // > thread (through an existing reference) to *happen before* deleting + // > the object in a different thread. This is achieved by a "release" + // > operation after dropping a reference (any access to the object + // > through this reference must obviously happened before), and an + // > "acquire" operation before deleting the object. + // + // [1]: (www.boost.org/doc/libs/1_55_0/doc/html/atomic/usage_examples.html) + // + // Thread sanitizer does not support atomic fences. Use an atomic load + // instead. + (*ptr).ref_cnt.load(Ordering::Acquire); + + // Drop the data + 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 + +/// ```compile_fail +/// use bytes::Bytes; +/// #[deny(unused_must_use)] +/// { +/// let mut b1 = Bytes::from("hello world"); +/// b1.split_to(6); +/// } +/// ``` +fn _split_to_must_use() {} + +/// ```compile_fail +/// use bytes::Bytes; +/// #[deny(unused_must_use)] +/// { +/// let mut b1 = Bytes::from("hello world"); +/// b1.split_off(6); +/// } +/// ``` +fn _split_off_must_use() {} + +// fuzz tests +#[cfg(all(test, loom))] +mod fuzz { + use loom::sync::Arc; + use loom::thread; + + use super::Bytes; + #[test] + fn bytes_cloning_vec() { + loom::model(|| { + let a = Bytes::from(b"abcdefgh".to_vec()); + let addr = a.as_ptr() as usize; + + // test the Bytes::clone is Sync by putting it in an Arc + let a1 = Arc::new(a); + let a2 = a1.clone(); + + let t1 = thread::spawn(move || { + let b: Bytes = (*a1).clone(); + assert_eq!(b.as_ptr() as usize, addr); + }); + + let t2 = thread::spawn(move || { + let b: Bytes = (*a2).clone(); + assert_eq!(b.as_ptr() as usize, addr); + }); + + t1.join().unwrap(); + t2.join().unwrap(); + }); + } +} diff --git a/src/bytes_mut.rs b/src/bytes_mut.rs new file mode 100644 index 0000000..70613b2 --- /dev/null +++ b/src/bytes_mut.rs @@ -0,0 +1,1812 @@ +use core::iter::{FromIterator, Iterator}; +use core::mem::{self, ManuallyDrop, MaybeUninit}; +use core::ops::{Deref, DerefMut}; +use core::ptr::{self, NonNull}; +use core::{cmp, fmt, hash, isize, slice, usize}; + +use alloc::{ + borrow::{Borrow, BorrowMut}, + boxed::Box, + string::String, + vec, + vec::Vec, +}; + +use crate::buf::{IntoIter, UninitSlice}; +use crate::bytes::Vtable; +#[allow(unused)] +use crate::loom::sync::atomic::AtomicMut; +use crate::loom::sync::atomic::{AtomicPtr, AtomicUsize, Ordering}; +use crate::{Buf, BufMut, Bytes}; + +/// A unique reference to a contiguous slice of memory. +/// +/// `BytesMut` represents a unique view into a potentially shared memory region. +/// Given the uniqueness guarantee, owners of `BytesMut` handles are able to +/// mutate the memory. +/// +/// `BytesMut` can be thought of as containing a `buf: Arc>`, an offset +/// into `buf`, a slice length, and a guarantee that no other `BytesMut` for the +/// same `buf` overlaps with its slice. That guarantee means that a write lock +/// is not required. +/// +/// # Growth +/// +/// `BytesMut`'s `BufMut` implementation will implicitly grow its buffer as +/// necessary. However, explicitly reserving the required space up-front before +/// a series of inserts will be more efficient. +/// +/// # Examples +/// +/// ``` +/// use bytes::{BytesMut, BufMut}; +/// +/// let mut buf = BytesMut::with_capacity(64); +/// +/// buf.put_u8(b'h'); +/// buf.put_u8(b'e'); +/// buf.put(&b"llo"[..]); +/// +/// assert_eq!(&buf[..], b"hello"); +/// +/// // Freeze the buffer so that it can be shared +/// let a = buf.freeze(); +/// +/// // This does not allocate, instead `b` points to the same memory. +/// let b = a.clone(); +/// +/// assert_eq!(&a[..], b"hello"); +/// assert_eq!(&b[..], b"hello"); +/// ``` +pub struct BytesMut { + ptr: NonNull, + len: usize, + cap: usize, + data: *mut Shared, +} + +// Thread-safe reference-counted container for the shared storage. This mostly +// the same as `core::sync::Arc` but without the weak counter. The ref counting +// fns are based on the ones found in `std`. +// +// The main reason to use `Shared` instead of `core::sync::Arc` is that it ends +// up making the overall code simpler and easier to reason about. This is due to +// some of the logic around setting `Inner::arc` and other ways the `arc` field +// is used. Using `Arc` ended up requiring a number of funky transmutes and +// other shenanigans to make it work. +struct Shared { + vec: Vec, + original_capacity_repr: usize, + ref_count: AtomicUsize, +} + +// Buffer storage strategy flags. +const KIND_ARC: usize = 0b0; +const KIND_VEC: usize = 0b1; +const KIND_MASK: usize = 0b1; + +// The max original capacity value. Any `Bytes` allocated with a greater initial +// capacity will default to this. +const MAX_ORIGINAL_CAPACITY_WIDTH: usize = 17; +// The original capacity algorithm will not take effect unless the originally +// allocated capacity was at least 1kb in size. +const MIN_ORIGINAL_CAPACITY_WIDTH: usize = 10; +// The original capacity is stored in powers of 2 starting at 1kb to a max of +// 64kb. Representing it as such requires only 3 bits of storage. +const ORIGINAL_CAPACITY_MASK: usize = 0b11100; +const ORIGINAL_CAPACITY_OFFSET: usize = 2; + +// When the storage is in the `Vec` representation, the pointer can be advanced +// at most this value. This is due to the amount of storage available to track +// the offset is usize - number of KIND bits and number of ORIGINAL_CAPACITY +// bits. +const VEC_POS_OFFSET: usize = 5; +const MAX_VEC_POS: usize = usize::MAX >> VEC_POS_OFFSET; +const NOT_VEC_POS_MASK: usize = 0b11111; + +#[cfg(target_pointer_width = "64")] +const PTR_WIDTH: usize = 64; +#[cfg(target_pointer_width = "32")] +const PTR_WIDTH: usize = 32; + +/* + * + * ===== BytesMut ===== + * + */ + +impl BytesMut { + /// Creates a new `BytesMut` with the specified capacity. + /// + /// The returned `BytesMut` will be able to hold at least `capacity` bytes + /// without reallocating. + /// + /// It is important to note that this function does not specify the length + /// of the returned `BytesMut`, but only the capacity. + /// + /// # Examples + /// + /// ``` + /// use bytes::{BytesMut, BufMut}; + /// + /// let mut bytes = BytesMut::with_capacity(64); + /// + /// // `bytes` contains no data, even though there is capacity + /// assert_eq!(bytes.len(), 0); + /// + /// bytes.put(&b"hello world"[..]); + /// + /// assert_eq!(&bytes[..], b"hello world"); + /// ``` + #[inline] + pub fn with_capacity(capacity: usize) -> BytesMut { + BytesMut::from_vec(Vec::with_capacity(capacity)) + } + + /// Creates a new `BytesMut` with default capacity. + /// + /// Resulting object has length 0 and unspecified capacity. + /// This function does not allocate. + /// + /// # Examples + /// + /// ``` + /// use bytes::{BytesMut, BufMut}; + /// + /// let mut bytes = BytesMut::new(); + /// + /// assert_eq!(0, bytes.len()); + /// + /// bytes.reserve(2); + /// bytes.put_slice(b"xy"); + /// + /// assert_eq!(&b"xy"[..], &bytes[..]); + /// ``` + #[inline] + pub fn new() -> BytesMut { + BytesMut::with_capacity(0) + } + + /// Returns the number of bytes contained in this `BytesMut`. + /// + /// # Examples + /// + /// ``` + /// use bytes::BytesMut; + /// + /// let b = BytesMut::from(&b"hello"[..]); + /// assert_eq!(b.len(), 5); + /// ``` + #[inline] + pub fn len(&self) -> usize { + self.len + } + + /// Returns true if the `BytesMut` has a length of 0. + /// + /// # Examples + /// + /// ``` + /// use bytes::BytesMut; + /// + /// let b = BytesMut::with_capacity(64); + /// assert!(b.is_empty()); + /// ``` + #[inline] + pub fn is_empty(&self) -> bool { + self.len == 0 + } + + /// Returns the number of bytes the `BytesMut` can hold without reallocating. + /// + /// # Examples + /// + /// ``` + /// use bytes::BytesMut; + /// + /// let b = BytesMut::with_capacity(64); + /// assert_eq!(b.capacity(), 64); + /// ``` + #[inline] + pub fn capacity(&self) -> usize { + self.cap + } + + /// Converts `self` into an immutable `Bytes`. + /// + /// The conversion is zero cost and is used to indicate that the slice + /// referenced by the handle will no longer be mutated. Once the conversion + /// is done, the handle can be cloned and shared across threads. + /// + /// # Examples + /// + /// ``` + /// use bytes::{BytesMut, BufMut}; + /// use std::thread; + /// + /// let mut b = BytesMut::with_capacity(64); + /// b.put(&b"hello world"[..]); + /// let b1 = b.freeze(); + /// let b2 = b1.clone(); + /// + /// let th = thread::spawn(move || { + /// assert_eq!(&b1[..], b"hello world"); + /// }); + /// + /// assert_eq!(&b2[..], b"hello world"); + /// th.join().unwrap(); + /// ``` + #[inline] + pub fn freeze(mut self) -> Bytes { + if self.kind() == KIND_VEC { + // Just re-use `Bytes` internal Vec vtable + unsafe { + let (off, _) = self.get_vec_pos(); + let vec = rebuild_vec(self.ptr.as_ptr(), self.len, self.cap, off); + mem::forget(self); + let mut b: Bytes = vec.into(); + b.advance(off); + b + } + } else { + debug_assert_eq!(self.kind(), KIND_ARC); + + let ptr = self.ptr.as_ptr(); + let len = self.len; + 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 + /// `BytesMut` contains elements `[at, capacity)`. + /// + /// This is an `O(1)` operation that just increases the reference count + /// and sets a few indices. + /// + /// # Examples + /// + /// ``` + /// use bytes::BytesMut; + /// + /// let mut a = BytesMut::from(&b"hello world"[..]); + /// let mut b = a.split_off(5); + /// + /// a[0] = b'j'; + /// b[0] = b'!'; + /// + /// assert_eq!(&a[..], b"jello"); + /// assert_eq!(&b[..], b"!world"); + /// ``` + /// + /// # Panics + /// + /// Panics if `at > capacity`. + #[must_use = "consider BytesMut::truncate if you don't need the other half"] + pub fn split_off(&mut self, at: usize) -> BytesMut { + assert!( + at <= self.capacity(), + "split_off out of bounds: {:?} <= {:?}", + at, + self.capacity(), + ); + unsafe { + let mut other = self.shallow_clone(); + other.set_start(at); + self.set_end(at); + other + } + } + + /// Removes the bytes from the current view, returning them in a new + /// `BytesMut` handle. + /// + /// Afterwards, `self` will be empty, but will retain any additional + /// capacity that it had before the operation. This is identical to + /// `self.split_to(self.len())`. + /// + /// This is an `O(1)` operation that just increases the reference count and + /// sets a few indices. + /// + /// # Examples + /// + /// ``` + /// use bytes::{BytesMut, BufMut}; + /// + /// let mut buf = BytesMut::with_capacity(1024); + /// buf.put(&b"hello world"[..]); + /// + /// let other = buf.split(); + /// + /// assert!(buf.is_empty()); + /// assert_eq!(1013, buf.capacity()); + /// + /// assert_eq!(other, b"hello world"[..]); + /// ``` + #[must_use = "consider BytesMut::advance(len()) if you don't need the other half"] + pub fn split(&mut self) -> BytesMut { + let len = self.len(); + self.split_to(len) + } + + /// Splits the buffer into two at the given index. + /// + /// Afterwards `self` contains elements `[at, len)`, and the returned `BytesMut` + /// contains elements `[0, at)`. + /// + /// This is an `O(1)` operation that just increases the reference count and + /// sets a few indices. + /// + /// # Examples + /// + /// ``` + /// use bytes::BytesMut; + /// + /// let mut a = BytesMut::from(&b"hello world"[..]); + /// let mut b = a.split_to(5); + /// + /// a[0] = b'!'; + /// b[0] = b'j'; + /// + /// assert_eq!(&a[..], b"!world"); + /// assert_eq!(&b[..], b"jello"); + /// ``` + /// + /// # Panics + /// + /// Panics if `at > len`. + #[must_use = "consider BytesMut::advance if you don't need the other half"] + pub fn split_to(&mut self, at: usize) -> BytesMut { + assert!( + at <= self.len(), + "split_to out of bounds: {:?} <= {:?}", + at, + self.len(), + ); + + unsafe { + let mut other = self.shallow_clone(); + other.set_end(at); + self.set_start(at); + other + } + } + + /// Shortens the buffer, keeping the first `len` bytes and dropping the + /// rest. + /// + /// 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. + /// + /// # Examples + /// + /// ``` + /// use bytes::BytesMut; + /// + /// let mut buf = BytesMut::from(&b"hello world"[..]); + /// buf.truncate(5); + /// assert_eq!(buf, b"hello"[..]); + /// ``` + /// + /// [`split_off`]: #method.split_off + pub fn truncate(&mut self, len: usize) { + if len <= self.len() { + unsafe { + self.set_len(len); + } + } + } + + /// Clears the buffer, removing all data. Existing capacity is preserved. + /// + /// # Examples + /// + /// ``` + /// use bytes::BytesMut; + /// + /// let mut buf = BytesMut::from(&b"hello world"[..]); + /// buf.clear(); + /// assert!(buf.is_empty()); + /// ``` + pub fn clear(&mut self) { + self.truncate(0); + } + + /// Resizes the buffer so that `len` is equal to `new_len`. + /// + /// If `new_len` is greater than `len`, the buffer is extended by the + /// difference with each additional byte set to `value`. If `new_len` is + /// less than `len`, the buffer is simply truncated. + /// + /// # Examples + /// + /// ``` + /// use bytes::BytesMut; + /// + /// let mut buf = BytesMut::new(); + /// + /// buf.resize(3, 0x1); + /// assert_eq!(&buf[..], &[0x1, 0x1, 0x1]); + /// + /// buf.resize(2, 0x2); + /// assert_eq!(&buf[..], &[0x1, 0x1]); + /// + /// buf.resize(4, 0x3); + /// assert_eq!(&buf[..], &[0x1, 0x1, 0x3, 0x3]); + /// ``` + pub fn resize(&mut self, new_len: usize, value: u8) { + let len = self.len(); + if new_len > len { + let additional = new_len - len; + self.reserve(additional); + unsafe { + let dst = self.chunk_mut().as_mut_ptr(); + ptr::write_bytes(dst, value, additional); + self.set_len(new_len); + } + } else { + self.truncate(new_len); + } + } + + /// Sets the length of the buffer. + /// + /// This will explicitly set the size of the buffer without actually + /// modifying the data, so it is up to the caller to ensure that the data + /// has been initialized. + /// + /// # Examples + /// + /// ``` + /// use bytes::BytesMut; + /// + /// let mut b = BytesMut::from(&b"hello world"[..]); + /// + /// unsafe { + /// b.set_len(5); + /// } + /// + /// assert_eq!(&b[..], b"hello"); + /// + /// unsafe { + /// b.set_len(11); + /// } + /// + /// assert_eq!(&b[..], b"hello world"); + /// ``` + #[inline] + pub unsafe fn set_len(&mut self, len: usize) { + debug_assert!(len <= self.cap, "set_len out of bounds"); + self.len = len; + } + + /// Reserves capacity for at least `additional` more bytes to be inserted + /// into the given `BytesMut`. + /// + /// More than `additional` bytes may be reserved in order to avoid frequent + /// 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 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 + /// + /// In the following example, a new buffer is allocated. + /// + /// ``` + /// use bytes::BytesMut; + /// + /// let mut buf = BytesMut::from(&b"hello"[..]); + /// buf.reserve(64); + /// assert!(buf.capacity() >= 69); + /// ``` + /// + /// In the following example, the existing buffer is reclaimed. + /// + /// ``` + /// use bytes::{BytesMut, BufMut}; + /// + /// let mut buf = BytesMut::with_capacity(128); + /// buf.put(&[0; 64][..]); + /// + /// let ptr = buf.as_ptr(); + /// let other = buf.split(); + /// + /// assert!(buf.is_empty()); + /// assert_eq!(buf.capacity(), 64); + /// + /// drop(other); + /// buf.reserve(128); + /// + /// assert_eq!(buf.capacity(), 128); + /// assert_eq!(buf.as_ptr(), ptr); + /// ``` + /// + /// # Panics + /// + /// Panics if the new capacity overflows `usize`. + #[inline] + pub fn reserve(&mut self, additional: usize) { + let len = self.len(); + let rem = self.capacity() - len; + + if additional <= rem { + // The handle can already store at least `additional` more bytes, so + // there is no further work needed to be done. + return; + } + + self.reserve_inner(additional); + } + + // In separate function to allow the short-circuits in `reserve` to + // be inline-able. Significant helps performance. + fn reserve_inner(&mut self, additional: usize) { + let len = self.len(); + let kind = self.kind(); + + if kind == KIND_VEC { + // If there's enough free space before the start of the buffer, then + // just copy the data backwards and reuse the already-allocated + // 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. + // + // 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)); + // 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); + + // Length stays constant, but since we moved backwards we + // can gain capacity back. + self.cap += off; + } else { + // 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().add(off)); + self.len = v.len() - off; + self.cap = v.capacity() - off; + } + + return; + } + } + + debug_assert_eq!(kind, KIND_ARC); + let shared: *mut Shared = self.data; + + // Reserving involves abandoning the currently shared buffer and + // allocating a new vector with the requested capacity. + // + // Compute the new capacity + let mut new_cap = len.checked_add(additional).expect("overflow"); + + let original_capacity; + let original_capacity_repr; + + unsafe { + original_capacity_repr = (*shared).original_capacity_repr; + original_capacity = original_capacity_from_repr(original_capacity_repr); + + // First, try to reclaim the buffer. This is possible if the current + // handle is the only outstanding handle pointing to the buffer. + if (*shared).is_unique() { + // This is the only handle to the buffer. It can be reclaimed. + // However, before doing the work of copying data, check to make + // sure that the vector has enough capacity. + let v = &mut (*shared).vec; + + 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! + + // `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); + + // 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); + + 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()); + + // 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); + } + } + + // Create a new vector to store the data + let mut v = ManuallyDrop::new(Vec::with_capacity(new_cap)); + + // Copy the bytes + v.extend_from_slice(self.as_ref()); + + // Release the shared handle. This must be done *after* the bytes are + // copied. + unsafe { release_shared(shared) }; + + // Update self + let data = (original_capacity_repr << ORIGINAL_CAPACITY_OFFSET) | KIND_VEC; + self.data = invalid_ptr(data); + self.ptr = vptr(v.as_mut_ptr()); + self.len = v.len(); + self.cap = v.capacity(); + } + + /// Appends given bytes to this `BytesMut`. + /// + /// If this `BytesMut` object does not have enough capacity, it is resized + /// first. + /// + /// # Examples + /// + /// ``` + /// use bytes::BytesMut; + /// + /// let mut buf = BytesMut::with_capacity(0); + /// buf.extend_from_slice(b"aaabbb"); + /// buf.extend_from_slice(b"cccddd"); + /// + /// assert_eq!(b"aaabbbcccddd", &buf[..]); + /// ``` + pub fn extend_from_slice(&mut self, extend: &[u8]) { + let cnt = extend.len(); + self.reserve(cnt); + + unsafe { + let dst = self.spare_capacity_mut(); + // Reserved above + debug_assert!(dst.len() >= cnt); + + ptr::copy_nonoverlapping(extend.as_ptr(), dst.as_mut_ptr().cast(), cnt); + } + + unsafe { + self.advance_mut(cnt); + } + } + + /// Absorbs a `BytesMut` that was previously split off. + /// + /// 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 + /// + /// ``` + /// use bytes::BytesMut; + /// + /// let mut buf = BytesMut::with_capacity(64); + /// buf.extend_from_slice(b"aaabbbcccddd"); + /// + /// let split = buf.split_off(6); + /// assert_eq!(b"aaabbb", &buf[..]); + /// assert_eq!(b"cccddd", &split[..]); + /// + /// buf.unsplit(split); + /// assert_eq!(b"aaabbbcccddd", &buf[..]); + /// ``` + pub fn unsplit(&mut self, other: BytesMut) { + if self.is_empty() { + *self = other; + return; + } + + if let Err(other) = self.try_unsplit(other) { + self.extend_from_slice(other.as_ref()); + } + } + + // private + + // For now, use a `Vec` to manage the memory for us, but we may want to + // change that in the future to some alternate allocator strategy. + // + // Thus, we don't expose an easy way to construct from a `Vec` since an + // internal change could make a simple pattern (`BytesMut::from(vec)`) + // suddenly a lot more expensive. + #[inline] + pub(crate) fn from_vec(mut vec: Vec) -> BytesMut { + let ptr = vptr(vec.as_mut_ptr()); + let len = vec.len(); + let cap = vec.capacity(); + mem::forget(vec); + + let original_capacity_repr = original_capacity_to_repr(cap); + let data = (original_capacity_repr << ORIGINAL_CAPACITY_OFFSET) | KIND_VEC; + + BytesMut { + ptr, + len, + cap, + data: invalid_ptr(data), + } + } + + #[inline] + fn as_slice(&self) -> &[u8] { + unsafe { slice::from_raw_parts(self.ptr.as_ptr(), self.len) } + } + + #[inline] + fn as_slice_mut(&mut self) -> &mut [u8] { + unsafe { slice::from_raw_parts_mut(self.ptr.as_ptr(), self.len) } + } + + unsafe fn set_start(&mut self, start: usize) { + // Setting the start to 0 is a no-op, so return early if this is the + // case. + if start == 0 { + return; + } + + debug_assert!(start <= self.cap, "internal: set_start out of bounds"); + + let kind = self.kind(); + + if kind == KIND_VEC { + // Setting the start when in vec representation is a little more + // complicated. First, we have to track how far ahead the + // "start" of the byte buffer from the beginning of the vec. We + // also have to ensure that we don't exceed the maximum shift. + let (mut pos, prev) = self.get_vec_pos(); + pos += start; + + if pos <= MAX_VEC_POS { + self.set_vec_pos(pos, prev); + } else { + // The repr must be upgraded to ARC. This will never happen + // on 64 bit systems and will only happen on 32 bit systems + // when shifting past 134,217,727 bytes. As such, we don't + // worry too much about performance here. + self.promote_to_shared(/*ref_count = */ 1); + } + } + + // 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().add(start)); + + if self.len >= start { + self.len -= start; + } else { + self.len = 0; + } + + self.cap -= start; + } + + unsafe fn set_end(&mut self, end: usize) { + debug_assert_eq!(self.kind(), KIND_ARC); + assert!(end <= self.cap, "set_end out of bounds"); + + self.cap = end; + self.len = cmp::min(self.len, end); + } + + fn try_unsplit(&mut self, other: BytesMut) -> Result<(), BytesMut> { + if other.capacity() == 0 { + return Ok(()); + } + + let ptr = unsafe { self.ptr.as_ptr().add(self.len) }; + if ptr == other.ptr.as_ptr() + && self.kind() == KIND_ARC + && other.kind() == KIND_ARC + && self.data == other.data + { + // Contiguous blocks, just combine directly + self.len += other.len; + self.cap += other.cap; + Ok(()) + } else { + Err(other) + } + } + + #[inline] + fn kind(&self) -> usize { + self.data as usize & KIND_MASK + } + + unsafe fn promote_to_shared(&mut self, ref_cnt: usize) { + debug_assert_eq!(self.kind(), KIND_VEC); + debug_assert!(ref_cnt == 1 || ref_cnt == 2); + + let original_capacity_repr = + (self.data as usize & ORIGINAL_CAPACITY_MASK) >> ORIGINAL_CAPACITY_OFFSET; + + // The vec offset cannot be concurrently mutated, so there + // should be no danger reading it. + let off = (self.data as usize) >> VEC_POS_OFFSET; + + // First, allocate a new `Shared` instance containing the + // `Vec` fields. It's important to note that `ptr`, `len`, + // and `cap` cannot be mutated without having `&mut self`. + // This means that these fields will not be concurrently + // updated and since the buffer hasn't been promoted to an + // `Arc`, those three fields still are the components of the + // vector. + let shared = Box::new(Shared { + vec: rebuild_vec(self.ptr.as_ptr(), self.len, self.cap, off), + original_capacity_repr, + ref_count: AtomicUsize::new(ref_cnt), + }); + + let shared = Box::into_raw(shared); + + // The pointer should be aligned, so this assert should + // always succeed. + debug_assert_eq!(shared as usize & KIND_MASK, KIND_ARC); + + self.data = shared; + } + + /// Makes an exact shallow clone of `self`. + /// + /// The kind of `self` doesn't matter, but this is unsafe + /// because the clone will have the same offsets. You must + /// be sure the returned value to the user doesn't allow + /// two views into the same range. + #[inline] + unsafe fn shallow_clone(&mut self) -> BytesMut { + if self.kind() == KIND_ARC { + increment_shared(self.data); + ptr::read(self) + } else { + self.promote_to_shared(/*ref_count = */ 2); + ptr::read(self) + } + } + + #[inline] + unsafe fn get_vec_pos(&mut self) -> (usize, usize) { + debug_assert_eq!(self.kind(), KIND_VEC); + + let prev = self.data as usize; + (prev >> VEC_POS_OFFSET, prev) + } + + #[inline] + unsafe fn set_vec_pos(&mut self, pos: usize, prev: usize) { + debug_assert_eq!(self.kind(), KIND_VEC); + debug_assert!(pos <= MAX_VEC_POS); + + 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] + pub fn spare_capacity_mut(&mut self) -> &mut [MaybeUninit] { + unsafe { + let ptr = self.ptr.as_ptr().add(self.len); + let len = self.cap - self.len; + + slice::from_raw_parts_mut(ptr.cast(), len) + } + } +} + +impl Drop for BytesMut { + fn drop(&mut self) { + let kind = self.kind(); + + if kind == KIND_VEC { + unsafe { + let (off, _) = self.get_vec_pos(); + + // Vector storage, free the vector + let _ = rebuild_vec(self.ptr.as_ptr(), self.len, self.cap, off); + } + } else if kind == KIND_ARC { + unsafe { release_shared(self.data) }; + } + } +} + +impl Buf for BytesMut { + #[inline] + fn remaining(&self) -> usize { + self.len() + } + + #[inline] + fn chunk(&self) -> &[u8] { + self.as_slice() + } + + #[inline] + fn advance(&mut self, cnt: usize) { + assert!( + cnt <= self.remaining(), + "cannot advance past `remaining`: {:?} <= {:?}", + cnt, + self.remaining(), + ); + unsafe { + self.set_start(cnt); + } + } + + fn copy_to_bytes(&mut self, len: usize) -> crate::Bytes { + self.split_to(len).freeze() + } +} + +unsafe impl BufMut for BytesMut { + #[inline] + fn remaining_mut(&self) -> usize { + usize::MAX - self.len() + } + + #[inline] + unsafe fn advance_mut(&mut self, cnt: usize) { + let new_len = self.len() + cnt; + assert!( + new_len <= self.cap, + "new_len = {}; capacity = {}", + new_len, + self.cap + ); + self.len = new_len; + } + + #[inline] + fn chunk_mut(&mut self) -> &mut UninitSlice { + if self.capacity() == self.len() { + self.reserve(64); + } + UninitSlice::from_slice(self.spare_capacity_mut()) + } + + // Specialize these methods so they can skip checking `remaining_mut` + // and `advance_mut`. + + fn put(&mut self, mut src: T) + where + Self: Sized, + { + while src.has_remaining() { + let s = src.chunk(); + let l = s.len(); + self.extend_from_slice(s); + src.advance(l); + } + } + + 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 { + #[inline] + fn as_ref(&self) -> &[u8] { + self.as_slice() + } +} + +impl Deref for BytesMut { + type Target = [u8]; + + #[inline] + fn deref(&self) -> &[u8] { + self.as_ref() + } +} + +impl AsMut<[u8]> for BytesMut { + #[inline] + fn as_mut(&mut self) -> &mut [u8] { + self.as_slice_mut() + } +} + +impl DerefMut for BytesMut { + #[inline] + fn deref_mut(&mut self) -> &mut [u8] { + self.as_mut() + } +} + +impl<'a> From<&'a [u8]> for BytesMut { + fn from(src: &'a [u8]) -> BytesMut { + BytesMut::from_vec(src.to_vec()) + } +} + +impl<'a> From<&'a str> for BytesMut { + fn from(src: &'a str) -> BytesMut { + BytesMut::from(src.as_bytes()) + } +} + +impl From for Bytes { + fn from(src: BytesMut) -> Bytes { + src.freeze() + } +} + +impl PartialEq for BytesMut { + fn eq(&self, other: &BytesMut) -> bool { + self.as_slice() == other.as_slice() + } +} + +impl PartialOrd for BytesMut { + fn partial_cmp(&self, other: &BytesMut) -> Option { + self.as_slice().partial_cmp(other.as_slice()) + } +} + +impl Ord for BytesMut { + fn cmp(&self, other: &BytesMut) -> cmp::Ordering { + self.as_slice().cmp(other.as_slice()) + } +} + +impl Eq for BytesMut {} + +impl Default for BytesMut { + #[inline] + fn default() -> BytesMut { + BytesMut::new() + } +} + +impl hash::Hash for BytesMut { + fn hash(&self, state: &mut H) + where + H: hash::Hasher, + { + let s: &[u8] = self.as_ref(); + s.hash(state); + } +} + +impl Borrow<[u8]> for BytesMut { + fn borrow(&self) -> &[u8] { + self.as_ref() + } +} + +impl BorrowMut<[u8]> for BytesMut { + fn borrow_mut(&mut self) -> &mut [u8] { + self.as_mut() + } +} + +impl fmt::Write for BytesMut { + #[inline] + fn write_str(&mut self, s: &str) -> fmt::Result { + if self.remaining_mut() >= s.len() { + self.put_slice(s.as_bytes()); + Ok(()) + } else { + Err(fmt::Error) + } + } + + #[inline] + fn write_fmt(&mut self, args: fmt::Arguments<'_>) -> fmt::Result { + fmt::write(self, args) + } +} + +impl Clone for BytesMut { + fn clone(&self) -> BytesMut { + BytesMut::from(&self[..]) + } +} + +impl IntoIterator for BytesMut { + type Item = u8; + type IntoIter = IntoIter; + + fn into_iter(self) -> Self::IntoIter { + IntoIter::new(self) + } +} + +impl<'a> IntoIterator for &'a BytesMut { + type Item = &'a u8; + type IntoIter = core::slice::Iter<'a, u8>; + + fn into_iter(self) -> Self::IntoIter { + self.as_ref().iter() + } +} + +impl Extend for BytesMut { + fn extend(&mut self, iter: T) + where + T: IntoIterator, + { + let iter = iter.into_iter(); + + let (lower, _) = iter.size_hint(); + self.reserve(lower); + + // TODO: optimize + // 1. If self.kind() == KIND_VEC, use Vec::extend + // 2. Make `reserve` inline-able + for b in iter { + self.reserve(1); + self.put_u8(b); + } + } +} + +impl<'a> Extend<&'a u8> for BytesMut { + fn extend(&mut self, iter: T) + where + T: IntoIterator, + { + 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) + } + } +} + +impl FromIterator for BytesMut { + fn from_iter>(into_iter: T) -> Self { + BytesMut::from_vec(Vec::from_iter(into_iter)) + } +} + +impl<'a> FromIterator<&'a u8> for BytesMut { + fn from_iter>(into_iter: T) -> Self { + BytesMut::from_iter(into_iter.into_iter().copied()) + } +} + +/* + * + * ===== Inner ===== + * + */ + +unsafe fn increment_shared(ptr: *mut Shared) { + let old_size = (*ptr).ref_count.fetch_add(1, Ordering::Relaxed); + + if old_size > isize::MAX as usize { + crate::abort(); + } +} + +unsafe fn release_shared(ptr: *mut Shared) { + // `Shared` storage... follow the drop steps from Arc. + if (*ptr).ref_count.fetch_sub(1, Ordering::Release) != 1 { + return; + } + + // This fence is needed to prevent reordering of use of the data and + // deletion of the data. Because it is marked `Release`, the decreasing + // of the reference count synchronizes with this `Acquire` fence. This + // means that use of the data happens before decreasing the reference + // count, which happens before this fence, which happens before the + // deletion of the data. + // + // As explained in the [Boost documentation][1], + // + // > It is important to enforce any possible access to the object in one + // > thread (through an existing reference) to *happen before* deleting + // > the object in a different thread. This is achieved by a "release" + // > operation after dropping a reference (any access to the object + // > through this reference must obviously happened before), and an + // > "acquire" operation before deleting the object. + // + // [1]: (www.boost.org/doc/libs/1_55_0/doc/html/atomic/usage_examples.html) + // + // Thread sanitizer does not support atomic fences. Use an atomic load + // instead. + (*ptr).ref_count.load(Ordering::Acquire); + + // Drop the data + drop(Box::from_raw(ptr)); +} + +impl Shared { + fn is_unique(&self) -> bool { + // The goal is to check if the current handle is the only handle + // that currently has access to the buffer. This is done by + // checking if the `ref_count` is currently 1. + // + // The `Acquire` ordering synchronizes with the `Release` as + // part of the `fetch_sub` in `release_shared`. The `fetch_sub` + // operation guarantees that any mutations done in other threads + // are ordered before the `ref_count` is decremented. As such, + // this `Acquire` will guarantee that those mutations are + // visible to the current thread. + self.ref_count.load(Ordering::Acquire) == 1 + } +} + +#[inline] +fn original_capacity_to_repr(cap: usize) -> usize { + let width = PTR_WIDTH - ((cap >> MIN_ORIGINAL_CAPACITY_WIDTH).leading_zeros() as usize); + cmp::min( + width, + MAX_ORIGINAL_CAPACITY_WIDTH - MIN_ORIGINAL_CAPACITY_WIDTH, + ) +} + +fn original_capacity_from_repr(repr: usize) -> usize { + if repr == 0 { + return 0; + } + + 1 << (repr + (MIN_ORIGINAL_CAPACITY_WIDTH - 1)) +} + +/* +#[test] +fn test_original_capacity_to_repr() { + assert_eq!(original_capacity_to_repr(0), 0); + + let max_width = 32; + + for width in 1..(max_width + 1) { + let cap = 1 << width - 1; + + let expected = if width < MIN_ORIGINAL_CAPACITY_WIDTH { + 0 + } else if width < MAX_ORIGINAL_CAPACITY_WIDTH { + width - MIN_ORIGINAL_CAPACITY_WIDTH + } else { + MAX_ORIGINAL_CAPACITY_WIDTH - MIN_ORIGINAL_CAPACITY_WIDTH + }; + + assert_eq!(original_capacity_to_repr(cap), expected); + + if width > 1 { + assert_eq!(original_capacity_to_repr(cap + 1), expected); + } + + // MIN_ORIGINAL_CAPACITY_WIDTH must be bigger than 7 to pass tests below + if width == MIN_ORIGINAL_CAPACITY_WIDTH + 1 { + assert_eq!(original_capacity_to_repr(cap - 24), expected - 1); + assert_eq!(original_capacity_to_repr(cap + 76), expected); + } else if width == MIN_ORIGINAL_CAPACITY_WIDTH + 2 { + assert_eq!(original_capacity_to_repr(cap - 1), expected - 1); + assert_eq!(original_capacity_to_repr(cap - 48), expected - 1); + } + } +} + +#[test] +fn test_original_capacity_from_repr() { + assert_eq!(0, original_capacity_from_repr(0)); + + let min_cap = 1 << MIN_ORIGINAL_CAPACITY_WIDTH; + + assert_eq!(min_cap, original_capacity_from_repr(1)); + assert_eq!(min_cap * 2, original_capacity_from_repr(2)); + assert_eq!(min_cap * 4, original_capacity_from_repr(3)); + assert_eq!(min_cap * 8, original_capacity_from_repr(4)); + assert_eq!(min_cap * 16, original_capacity_from_repr(5)); + assert_eq!(min_cap * 32, original_capacity_from_repr(6)); + assert_eq!(min_cap * 64, original_capacity_from_repr(7)); +} +*/ + +unsafe impl Send for BytesMut {} +unsafe impl Sync for BytesMut {} + +/* + * + * ===== PartialEq / PartialOrd ===== + * + */ + +impl PartialEq<[u8]> for BytesMut { + fn eq(&self, other: &[u8]) -> bool { + &**self == other + } +} + +impl PartialOrd<[u8]> for BytesMut { + fn partial_cmp(&self, other: &[u8]) -> Option { + (**self).partial_cmp(other) + } +} + +impl PartialEq for [u8] { + fn eq(&self, other: &BytesMut) -> bool { + *other == *self + } +} + +impl PartialOrd for [u8] { + fn partial_cmp(&self, other: &BytesMut) -> Option { + <[u8] as PartialOrd<[u8]>>::partial_cmp(self, other) + } +} + +impl PartialEq for BytesMut { + fn eq(&self, other: &str) -> bool { + &**self == other.as_bytes() + } +} + +impl PartialOrd for BytesMut { + fn partial_cmp(&self, other: &str) -> Option { + (**self).partial_cmp(other.as_bytes()) + } +} + +impl PartialEq for str { + fn eq(&self, other: &BytesMut) -> bool { + *other == *self + } +} + +impl PartialOrd for str { + fn partial_cmp(&self, other: &BytesMut) -> Option { + <[u8] as PartialOrd<[u8]>>::partial_cmp(self.as_bytes(), other) + } +} + +impl PartialEq> for BytesMut { + fn eq(&self, other: &Vec) -> bool { + *self == other[..] + } +} + +impl PartialOrd> for BytesMut { + fn partial_cmp(&self, other: &Vec) -> Option { + (**self).partial_cmp(&other[..]) + } +} + +impl PartialEq for Vec { + fn eq(&self, other: &BytesMut) -> bool { + *other == *self + } +} + +impl PartialOrd for Vec { + fn partial_cmp(&self, other: &BytesMut) -> Option { + other.partial_cmp(self) + } +} + +impl PartialEq for BytesMut { + fn eq(&self, other: &String) -> bool { + *self == other[..] + } +} + +impl PartialOrd for BytesMut { + fn partial_cmp(&self, other: &String) -> Option { + (**self).partial_cmp(other.as_bytes()) + } +} + +impl PartialEq for String { + fn eq(&self, other: &BytesMut) -> bool { + *other == *self + } +} + +impl PartialOrd for String { + fn partial_cmp(&self, other: &BytesMut) -> Option { + <[u8] as PartialOrd<[u8]>>::partial_cmp(self.as_bytes(), other) + } +} + +impl<'a, T: ?Sized> PartialEq<&'a T> for BytesMut +where + BytesMut: PartialEq, +{ + fn eq(&self, other: &&'a T) -> bool { + *self == **other + } +} + +impl<'a, T: ?Sized> PartialOrd<&'a T> for BytesMut +where + BytesMut: PartialOrd, +{ + fn partial_cmp(&self, other: &&'a T) -> Option { + self.partial_cmp(*other) + } +} + +impl PartialEq for &[u8] { + fn eq(&self, other: &BytesMut) -> bool { + *other == *self + } +} + +impl PartialOrd for &[u8] { + fn partial_cmp(&self, other: &BytesMut) -> Option { + <[u8] as PartialOrd<[u8]>>::partial_cmp(self, other) + } +} + +impl PartialEq for &str { + fn eq(&self, other: &BytesMut) -> bool { + *other == *self + } +} + +impl PartialOrd for &str { + fn partial_cmp(&self, other: &BytesMut) -> Option { + other.partial_cmp(self) + } +} + +impl PartialEq for Bytes { + fn eq(&self, other: &BytesMut) -> bool { + other[..] == self[..] + } +} + +impl PartialEq for BytesMut { + fn eq(&self, other: &Bytes) -> bool { + 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 + } +} + +#[inline] +fn vptr(ptr: *mut u8) -> NonNull { + if cfg!(debug_assertions) { + NonNull::new(ptr).expect("Vec pointer should be non-null") + } else { + unsafe { NonNull::new_unchecked(ptr) } + } +} + +/// 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; + cap += off; + + Vec::from_raw_parts(ptr, len, cap) +} + +// ===== impl SharedVtable ===== + +static SHARED_VTABLE: Vtable = Vtable { + clone: shared_v_clone, + to_vec: shared_v_to_vec, + drop: shared_v_drop, +}; + +unsafe fn shared_v_clone(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Bytes { + let shared = data.load(Ordering::Relaxed) as *mut Shared; + increment_shared(shared); + + 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); + }); +} + +// compile-fails + +/// ```compile_fail +/// use bytes::BytesMut; +/// #[deny(unused_must_use)] +/// { +/// let mut b1 = BytesMut::from("hello world"); +/// b1.split_to(6); +/// } +/// ``` +fn _split_to_must_use() {} + +/// ```compile_fail +/// use bytes::BytesMut; +/// #[deny(unused_must_use)] +/// { +/// let mut b1 = BytesMut::from("hello world"); +/// b1.split_off(6); +/// } +/// ``` +fn _split_off_must_use() {} + +/// ```compile_fail +/// use bytes::BytesMut; +/// #[deny(unused_must_use)] +/// { +/// let mut b1 = BytesMut::from("hello world"); +/// b1.split(); +/// } +/// ``` +fn _split_must_use() {} + +// fuzz tests +#[cfg(all(test, loom))] +mod fuzz { + use loom::sync::Arc; + use loom::thread; + + use super::BytesMut; + use crate::Bytes; + + #[test] + fn bytes_mut_cloning_frozen() { + loom::model(|| { + let a = BytesMut::from(&b"abcdefgh"[..]).split().freeze(); + let addr = a.as_ptr() as usize; + + // test the Bytes::clone is Sync by putting it in an Arc + let a1 = Arc::new(a); + let a2 = a1.clone(); + + let t1 = thread::spawn(move || { + let b: Bytes = (*a1).clone(); + assert_eq!(b.as_ptr() as usize, addr); + }); + + let t2 = thread::spawn(move || { + let b: Bytes = (*a2).clone(); + assert_eq!(b.as_ptr() as usize, addr); + }); + + t1.join().unwrap(); + t2.join().unwrap(); + }); + } +} diff --git a/src/fmt/debug.rs b/src/fmt/debug.rs new file mode 100644 index 0000000..83de695 --- /dev/null +++ b/src/fmt/debug.rs @@ -0,0 +1,49 @@ +use core::fmt::{Debug, Formatter, Result}; + +use super::BytesRef; +use crate::{Bytes, BytesMut}; + +/// Alternative implementation of `std::fmt::Debug` for byte slice. +/// +/// Standard `Debug` implementation for `[u8]` is comma separated +/// list of numbers. Since large amount of byte strings are in fact +/// ASCII strings or contain a lot of ASCII strings (e. g. HTTP), +/// it is convenient to print strings as ASCII when possible. +impl Debug for BytesRef<'_> { + fn fmt(&self, f: &mut Formatter<'_>) -> Result { + write!(f, "b\"")?; + for &b in self.0 { + // https://doc.rust-lang.org/reference/tokens.html#byte-escapes + if b == b'\n' { + write!(f, "\\n")?; + } else if b == b'\r' { + write!(f, "\\r")?; + } else if b == b'\t' { + write!(f, "\\t")?; + } else if b == b'\\' || b == b'"' { + write!(f, "\\{}", b as char)?; + } else if b == b'\0' { + write!(f, "\\0")?; + // ASCII printable + } else if (0x20..0x7f).contains(&b) { + write!(f, "{}", b as char)?; + } else { + write!(f, "\\x{:02x}", b)?; + } + } + write!(f, "\"")?; + Ok(()) + } +} + +impl Debug for Bytes { + fn fmt(&self, f: &mut Formatter<'_>) -> Result { + 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) + } +} diff --git a/src/fmt/hex.rs b/src/fmt/hex.rs new file mode 100644 index 0000000..97a749a --- /dev/null +++ b/src/fmt/hex.rs @@ -0,0 +1,37 @@ +use core::fmt::{Formatter, LowerHex, Result, UpperHex}; + +use super::BytesRef; +use crate::{Bytes, BytesMut}; + +impl LowerHex for BytesRef<'_> { + fn fmt(&self, f: &mut Formatter<'_>) -> Result { + for &b in self.0 { + write!(f, "{:02x}", b)?; + } + Ok(()) + } +} + +impl UpperHex for BytesRef<'_> { + fn fmt(&self, f: &mut Formatter<'_>) -> Result { + for &b in self.0 { + write!(f, "{:02X}", b)?; + } + Ok(()) + } +} + +macro_rules! hex_impl { + ($tr:ident, $ty:ty) => { + impl $tr for $ty { + fn fmt(&self, f: &mut Formatter<'_>) -> Result { + $tr::fmt(&BytesRef(self.as_ref()), f) + } + } + }; +} + +hex_impl!(LowerHex, Bytes); +hex_impl!(LowerHex, BytesMut); +hex_impl!(UpperHex, Bytes); +hex_impl!(UpperHex, BytesMut); diff --git a/src/fmt/mod.rs b/src/fmt/mod.rs new file mode 100644 index 0000000..676d15f --- /dev/null +++ b/src/fmt/mod.rs @@ -0,0 +1,5 @@ +mod debug; +mod hex; + +/// `BytesRef` is not a part of public API of bytes crate. +struct BytesRef<'a>(&'a [u8]); diff --git a/src/lib.rs b/src/lib.rs new file mode 100644 index 0000000..af436b3 --- /dev/null +++ b/src/lib.rs @@ -0,0 +1,117 @@ +#![warn(missing_docs, missing_debug_implementations, rust_2018_idioms)] +#![doc(test( + no_crate_inject, + 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. +//! +//! The `bytes` crate provides an efficient byte buffer structure +//! ([`Bytes`](struct.Bytes.html)) and traits for working with buffer +//! implementations ([`Buf`], [`BufMut`]). +//! +//! [`Buf`]: trait.Buf.html +//! [`BufMut`]: trait.BufMut.html +//! +//! # `Bytes` +//! +//! `Bytes` is an efficient container for storing and operating on contiguous +//! slices of memory. It is intended for use primarily in networking code, but +//! could have applications elsewhere as well. +//! +//! `Bytes` values facilitate zero-copy network programming by allowing multiple +//! `Bytes` objects to point to the same underlying memory. This is managed by +//! using a reference count to track when the memory is no longer needed and can +//! be freed. +//! +//! A `Bytes` handle can be created directly from an existing byte store (such as `&[u8]` +//! or `Vec`), but usually a `BytesMut` is used first and written to. For +//! example: +//! +//! ```rust +//! use bytes::{BytesMut, BufMut}; +//! +//! let mut buf = BytesMut::with_capacity(1024); +//! buf.put(&b"hello world"[..]); +//! buf.put_u16(1234); +//! +//! let a = buf.split(); +//! assert_eq!(a, b"hello world\x04\xD2"[..]); +//! +//! buf.put(&b"goodbye world"[..]); +//! +//! let b = buf.split(); +//! assert_eq!(b, b"goodbye world"[..]); +//! +//! assert_eq!(buf.capacity(), 998); +//! ``` +//! +//! In the above example, only a single buffer of 1024 is allocated. The handles +//! `a` and `b` will share the underlying buffer and maintain indices tracking +//! the view into the buffer represented by the handle. +//! +//! See the [struct docs] for more details. +//! +//! [struct docs]: struct.Bytes.html +//! +//! # `Buf`, `BufMut` +//! +//! These two traits provide read and write access to buffers. The underlying +//! storage may or may not be in contiguous memory. For example, `Bytes` is a +//! buffer that guarantees contiguous memory, but a [rope] stores the bytes in +//! disjoint chunks. `Buf` and `BufMut` maintain cursors tracking the current +//! position in the underlying byte storage. When bytes are read or written, the +//! cursor is advanced. +//! +//! [rope]: https://en.wikipedia.org/wiki/Rope_(data_structure) +//! +//! ## Relation with `Read` and `Write` +//! +//! At first glance, it may seem that `Buf` and `BufMut` overlap in +//! functionality with `std::io::Read` and `std::io::Write`. However, they +//! serve different purposes. A buffer is the value that is provided as an +//! argument to `Read::read` and `Write::write`. `Read` and `Write` may then +//! perform a syscall, which has the potential of failing. Operations on `Buf` +//! and `BufMut` are infallible. + +extern crate alloc; + +#[cfg(feature = "std")] +extern crate std; + +pub mod buf; +pub use crate::buf::{Buf, BufMut}; + +mod bytes; +mod bytes_mut; +mod fmt; +mod loom; +pub use crate::bytes::Bytes; +pub use crate::bytes_mut::BytesMut; + +// Optional Serde support +#[cfg(feature = "serde")] +mod serde; + +#[inline(never)] +#[cold] +fn abort() -> ! { + #[cfg(feature = "std")] + { + std::process::abort(); + } + + #[cfg(not(feature = "std"))] + { + struct Abort; + impl Drop for Abort { + fn drop(&mut self) { + panic!(); + } + } + let _a = Abort; + panic!("abort"); + } +} diff --git a/src/loom.rs b/src/loom.rs new file mode 100644 index 0000000..9e6b2d5 --- /dev/null +++ b/src/loom.rs @@ -0,0 +1,30 @@ +#[cfg(not(all(test, loom)))] +pub(crate) mod sync { + pub(crate) mod atomic { + pub(crate) use core::sync::atomic::{AtomicPtr, AtomicUsize, Ordering}; + + pub(crate) trait AtomicMut { + fn with_mut(&mut self, f: F) -> R + where + F: FnOnce(&mut *mut T) -> R; + } + + impl AtomicMut for AtomicPtr { + fn with_mut(&mut self, f: F) -> R + where + F: FnOnce(&mut *mut T) -> R, + { + f(self.get_mut()) + } + } + } +} + +#[cfg(all(test, loom))] +pub(crate) mod sync { + pub(crate) mod atomic { + pub(crate) use loom::sync::atomic::{AtomicPtr, AtomicUsize, Ordering}; + + pub(crate) trait AtomicMut {} + } +} diff --git a/src/serde.rs b/src/serde.rs new file mode 100644 index 0000000..0a5bd14 --- /dev/null +++ b/src/serde.rs @@ -0,0 +1,89 @@ +use super::{Bytes, BytesMut}; +use alloc::string::String; +use alloc::vec::Vec; +use core::{cmp, fmt}; +use serde::{de, Deserialize, Deserializer, Serialize, Serializer}; + +macro_rules! serde_impl { + ($ty:ident, $visitor_ty:ident, $from_slice:ident, $from_vec:ident) => { + impl Serialize for $ty { + #[inline] + fn serialize(&self, serializer: S) -> Result + where + S: Serializer, + { + serializer.serialize_bytes(&self) + } + } + + struct $visitor_ty; + + impl<'de> de::Visitor<'de> for $visitor_ty { + type Value = $ty; + + fn expecting(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result { + formatter.write_str("byte array") + } + + #[inline] + fn visit_seq(self, mut seq: V) -> Result + where + V: de::SeqAccess<'de>, + { + let len = cmp::min(seq.size_hint().unwrap_or(0), 4096); + let mut values: Vec = Vec::with_capacity(len); + + while let Some(value) = seq.next_element()? { + values.push(value); + } + + Ok($ty::$from_vec(values)) + } + + #[inline] + fn visit_bytes(self, v: &[u8]) -> Result + where + E: de::Error, + { + Ok($ty::$from_slice(v)) + } + + #[inline] + fn visit_byte_buf(self, v: Vec) -> Result + where + E: de::Error, + { + Ok($ty::$from_vec(v)) + } + + #[inline] + fn visit_str(self, v: &str) -> Result + where + E: de::Error, + { + Ok($ty::$from_slice(v.as_bytes())) + } + + #[inline] + fn visit_string(self, v: String) -> Result + where + E: de::Error, + { + Ok($ty::$from_vec(v.into_bytes())) + } + } + + impl<'de> Deserialize<'de> for $ty { + #[inline] + fn deserialize(deserializer: D) -> Result<$ty, D::Error> + where + D: Deserializer<'de>, + { + deserializer.deserialize_byte_buf($visitor_ty) + } + } + }; +} + +serde_impl!(Bytes, BytesVisitor, copy_from_slice, from); +serde_impl!(BytesMut, BytesMutVisitor, from, from_vec); diff --git a/tests/test_buf.rs b/tests/test_buf.rs new file mode 100644 index 0000000..fbad003 --- /dev/null +++ b/tests/test_buf.rs @@ -0,0 +1,120 @@ +#![warn(rust_2018_idioms)] + +use bytes::Buf; +#[cfg(feature = "std")] +use std::io::IoSlice; + +#[test] +fn test_fresh_cursor_vec() { + let mut buf = &b"hello"[..]; + + assert_eq!(buf.remaining(), 5); + assert_eq!(buf.chunk(), b"hello"); + + buf.advance(2); + + assert_eq!(buf.remaining(), 3); + assert_eq!(buf.chunk(), b"llo"); + + buf.advance(3); + + assert_eq!(buf.remaining(), 0); + assert_eq!(buf.chunk(), b""); +} + +#[test] +fn test_get_u8() { + let mut buf = &b"\x21zomg"[..]; + assert_eq!(0x21, buf.get_u8()); +} + +#[test] +fn test_get_u16() { + let mut buf = &b"\x21\x54zomg"[..]; + assert_eq!(0x2154, buf.get_u16()); + let mut buf = &b"\x21\x54zomg"[..]; + assert_eq!(0x5421, buf.get_u16_le()); +} + +#[test] +#[should_panic] +fn test_get_u16_buffer_underflow() { + let mut buf = &b"\x21"[..]; + buf.get_u16(); +} + +#[cfg(feature = "std")] +#[test] +fn test_bufs_vec() { + let buf = &b"hello world"[..]; + + let b1: &[u8] = &mut []; + let b2: &[u8] = &mut []; + + let mut dst = [IoSlice::new(b1), IoSlice::new(b2)]; + + assert_eq!(1, buf.chunks_vectored(&mut dst[..])); +} + +#[test] +fn test_vec_deque() { + use std::collections::VecDeque; + + let mut buffer: VecDeque = VecDeque::new(); + buffer.extend(b"hello world"); + assert_eq!(11, buffer.remaining()); + assert_eq!(b"hello world", buffer.chunk()); + buffer.advance(6); + assert_eq!(b"world", buffer.chunk()); + buffer.extend(b" piece"); + let mut out = [0; 11]; + buffer.copy_to_slice(&mut out); + assert_eq!(b"world piece", &out[..]); +} + +#[test] +fn test_deref_buf_forwards() { + struct Special; + + impl Buf for Special { + fn remaining(&self) -> usize { + unreachable!("remaining"); + } + + fn chunk(&self) -> &[u8] { + unreachable!("chunk"); + } + + fn advance(&mut self, _: usize) { + unreachable!("advance"); + } + + fn get_u8(&mut self) -> u8 { + // specialized! + b'x' + } + } + + // these should all use the specialized method + assert_eq!(Special.get_u8(), b'x'); + assert_eq!((&mut Special as &mut dyn Buf).get_u8(), b'x'); + assert_eq!((Box::new(Special) as Box).get_u8(), b'x'); + assert_eq!(Box::new(Special).get_u8(), b'x'); +} + +#[test] +fn copy_to_bytes_less() { + let mut buf = &b"hello world"[..]; + + let bytes = buf.copy_to_bytes(5); + assert_eq!(bytes, &b"hello"[..]); + assert_eq!(buf, &b" world"[..]) +} + +#[test] +#[should_panic] +fn copy_to_bytes_overflow() { + let mut buf = &b"hello world"[..]; + + let _bytes = buf.copy_to_bytes(12); +} diff --git a/tests/test_buf_mut.rs b/tests/test_buf_mut.rs new file mode 100644 index 0000000..53f4e86 --- /dev/null +++ b/tests/test_buf_mut.rs @@ -0,0 +1,178 @@ +#![warn(rust_2018_idioms)] + +use bytes::buf::UninitSlice; +use bytes::{BufMut, BytesMut}; +use core::fmt::Write; +use core::usize; + +#[test] +fn test_vec_as_mut_buf() { + let mut buf = Vec::with_capacity(64); + + assert_eq!(buf.remaining_mut(), isize::MAX as usize); + + assert!(buf.chunk_mut().len() >= 64); + + buf.put(&b"zomg"[..]); + + assert_eq!(&buf, b"zomg"); + + assert_eq!(buf.remaining_mut(), isize::MAX as usize - 4); + assert_eq!(buf.capacity(), 64); + + for _ in 0..16 { + buf.put(&b"zomg"[..]); + } + + 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); + buf.put_u8(33); + assert_eq!(b"\x21", &buf[..]); +} + +#[test] +fn test_put_u16() { + let mut buf = Vec::with_capacity(8); + buf.put_u16(8532); + assert_eq!(b"\x21\x54", &buf[..]); + + buf.clear(); + buf.put_u16_le(8532); + 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() { + // Verify fix for #354 + let mut buf = Vec::with_capacity(8); + unsafe { + buf.advance_mut(12); + } +} + +#[test] +fn test_clone() { + let mut buf = BytesMut::with_capacity(100); + buf.write_str("this is a test").unwrap(); + let buf2 = buf.clone(); + + buf.write_str(" of our emergency broadcast system").unwrap(); + assert!(buf != buf2); +} + +#[test] +fn test_mut_slice() { + let mut v = vec![0, 0, 0, 0]; + let mut s = &mut v[..]; + s.put_u32(42); + + assert_eq!(s.len(), 0); + assert_eq!(&v, &[0, 0, 0, 42]); +} + +#[test] +fn test_slice_put_bytes() { + let mut v = [0, 0, 0, 0]; + let mut s = &mut v[..]; + s.put_u8(17); + s.put_bytes(19, 2); + assert_eq!(1, s.remaining_mut()); + assert_eq!(&[17, 19, 19, 0], &v[..]); +} + +#[test] +fn test_deref_bufmut_forwards() { + struct Special; + + unsafe impl BufMut for Special { + fn remaining_mut(&self) -> usize { + unreachable!("remaining_mut"); + } + + fn chunk_mut(&mut self) -> &mut UninitSlice { + unreachable!("chunk_mut"); + } + + unsafe fn advance_mut(&mut self, _: usize) { + unreachable!("advance"); + } + + fn put_u8(&mut self, _: u8) { + // specialized! + } + } + + // these should all use the specialized method + Special.put_u8(b'x'); + (&mut Special as &mut dyn BufMut).put_u8(b'x'); + (Box::new(Special) as Box).put_u8(b'x'); + Box::new(Special).put_u8(b'x'); +} + +#[test] +#[should_panic] +fn write_byte_panics_if_out_of_bounds() { + let mut data = [b'b', b'a', b'r']; + + let slice = unsafe { UninitSlice::from_raw_parts_mut(data.as_mut_ptr(), 3) }; + slice.write_byte(4, b'f'); +} + +#[test] +#[should_panic] +fn copy_from_slice_panics_if_different_length_1() { + let mut data = [b'b', b'a', b'r']; + + let slice = unsafe { UninitSlice::from_raw_parts_mut(data.as_mut_ptr(), 3) }; + slice.copy_from_slice(b"a"); +} + +#[test] +#[should_panic] +fn copy_from_slice_panics_if_different_length_2() { + let mut data = [b'b', b'a', b'r']; + + let slice = unsafe { UninitSlice::from_raw_parts_mut(data.as_mut_ptr(), 3) }; + slice.copy_from_slice(b"abcd"); +} diff --git a/tests/test_bytes.rs b/tests/test_bytes.rs new file mode 100644 index 0000000..5ec60a5 --- /dev/null +++ b/tests/test_bytes.rs @@ -0,0 +1,1210 @@ +#![warn(rust_2018_idioms)] + +use bytes::{Buf, BufMut, Bytes, BytesMut}; + +use std::usize; + +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() {} + +#[test] +fn test_bounds() { + is_sync::(); + is_sync::(); + is_send::(); + is_send::(); +} + +#[test] +fn test_layout() { + use std::mem; + + assert_eq!( + mem::size_of::(), + mem::size_of::() * 4, + "Bytes size should be 4 words", + ); + assert_eq!( + mem::size_of::(), + mem::size_of::() * 4, + "BytesMut should be 4 words", + ); + + assert_eq!( + mem::size_of::(), + mem::size_of::>(), + "Bytes should be same size as Option", + ); + + assert_eq!( + mem::size_of::(), + mem::size_of::>(), + "BytesMut should be same size as Option", + ); +} + +#[test] +fn from_slice() { + let a = Bytes::from(&b"abcdefgh"[..]); + assert_eq!(a, b"abcdefgh"[..]); + assert_eq!(a, &b"abcdefgh"[..]); + assert_eq!(a, Vec::from(&b"abcdefgh"[..])); + assert_eq!(b"abcdefgh"[..], a); + assert_eq!(&b"abcdefgh"[..], a); + assert_eq!(Vec::from(&b"abcdefgh"[..]), a); + + let a = BytesMut::from(&b"abcdefgh"[..]); + assert_eq!(a, b"abcdefgh"[..]); + assert_eq!(a, &b"abcdefgh"[..]); + assert_eq!(a, Vec::from(&b"abcdefgh"[..])); + assert_eq!(b"abcdefgh"[..], a); + assert_eq!(&b"abcdefgh"[..], a); + assert_eq!(Vec::from(&b"abcdefgh"[..]), a); +} + +#[test] +fn fmt() { + let a = format!("{:?}", Bytes::from(&b"abcdefg"[..])); + let b = "b\"abcdefg\""; + + assert_eq!(a, b); + + let a = format!("{:?}", BytesMut::from(&b"abcdefg"[..])); + assert_eq!(a, b); +} + +#[test] +fn fmt_write() { + use std::fmt::Write; + use std::iter::FromIterator; + let s = String::from_iter((0..10).map(|_| "abcdefg")); + + let mut a = BytesMut::with_capacity(64); + write!(a, "{}", &s[..64]).unwrap(); + assert_eq!(a, s[..64].as_bytes()); + + let mut b = BytesMut::with_capacity(64); + write!(b, "{}", &s[..32]).unwrap(); + write!(b, "{}", &s[32..64]).unwrap(); + assert_eq!(b, s[..64].as_bytes()); + + let mut c = BytesMut::with_capacity(64); + write!(c, "{}", s).unwrap(); + assert_eq!(c, s[..].as_bytes()); +} + +#[test] +fn len() { + let a = Bytes::from(&b"abcdefg"[..]); + assert_eq!(a.len(), 7); + + let a = BytesMut::from(&b"abcdefg"[..]); + assert_eq!(a.len(), 7); + + let a = Bytes::from(&b""[..]); + assert!(a.is_empty()); + + let a = BytesMut::from(&b""[..]); + assert!(a.is_empty()); +} + +#[test] +fn index() { + let a = Bytes::from(&b"hello world"[..]); + assert_eq!(a[0..5], *b"hello"); +} + +#[test] +fn slice() { + let a = Bytes::from(&b"hello world"[..]); + + let b = a.slice(3..5); + assert_eq!(b, b"lo"[..]); + + let b = a.slice(0..0); + assert_eq!(b, b""[..]); + + let b = a.slice(3..3); + assert_eq!(b, b""[..]); + + let b = a.slice(a.len()..a.len()); + assert_eq!(b, b""[..]); + + let b = a.slice(..5); + assert_eq!(b, b"hello"[..]); + + let b = a.slice(3..); + assert_eq!(b, b"lo world"[..]); +} + +#[test] +#[should_panic] +fn slice_oob_1() { + let a = Bytes::from(&b"hello world"[..]); + a.slice(5..44); +} + +#[test] +#[should_panic] +fn slice_oob_2() { + let a = Bytes::from(&b"hello world"[..]); + a.slice(44..49); +} + +#[test] +fn split_off() { + let mut hello = Bytes::from(&b"helloworld"[..]); + let world = hello.split_off(5); + + assert_eq!(hello, &b"hello"[..]); + assert_eq!(world, &b"world"[..]); + + let mut hello = BytesMut::from(&b"helloworld"[..]); + let world = hello.split_off(5); + + assert_eq!(hello, &b"hello"[..]); + assert_eq!(world, &b"world"[..]); +} + +#[test] +#[should_panic] +fn split_off_oob() { + let mut hello = Bytes::from(&b"helloworld"[..]); + let _ = hello.split_off(44); +} + +#[test] +fn split_off_uninitialized() { + let mut bytes = BytesMut::with_capacity(1024); + let other = bytes.split_off(128); + + assert_eq!(bytes.len(), 0); + assert_eq!(bytes.capacity(), 128); + + assert_eq!(other.len(), 0); + assert_eq!(other.capacity(), 896); +} + +#[test] +fn split_off_to_loop() { + let s = b"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"; + + for i in 0..(s.len() + 1) { + { + let mut bytes = Bytes::from(&s[..]); + let off = bytes.split_off(i); + assert_eq!(i, bytes.len()); + let mut sum = Vec::new(); + sum.extend(bytes.iter()); + sum.extend(off.iter()); + assert_eq!(&s[..], &sum[..]); + } + { + let mut bytes = BytesMut::from(&s[..]); + let off = bytes.split_off(i); + assert_eq!(i, bytes.len()); + let mut sum = Vec::new(); + sum.extend(&bytes); + sum.extend(&off); + assert_eq!(&s[..], &sum[..]); + } + { + let mut bytes = Bytes::from(&s[..]); + let off = bytes.split_to(i); + assert_eq!(i, off.len()); + let mut sum = Vec::new(); + sum.extend(off.iter()); + sum.extend(bytes.iter()); + assert_eq!(&s[..], &sum[..]); + } + { + let mut bytes = BytesMut::from(&s[..]); + let off = bytes.split_to(i); + assert_eq!(i, off.len()); + let mut sum = Vec::new(); + sum.extend(&off); + sum.extend(&bytes); + assert_eq!(&s[..], &sum[..]); + } + } +} + +#[test] +fn split_to_1() { + // Static + let mut a = Bytes::from_static(SHORT); + let b = a.split_to(4); + + assert_eq!(SHORT[4..], a); + assert_eq!(SHORT[..4], b); + + // Allocated + let mut a = Bytes::copy_from_slice(LONG); + let b = a.split_to(4); + + assert_eq!(LONG[4..], a); + assert_eq!(LONG[..4], b); + + let mut a = Bytes::copy_from_slice(LONG); + let b = a.split_to(30); + + assert_eq!(LONG[30..], a); + assert_eq!(LONG[..30], b); +} + +#[test] +fn split_to_2() { + let mut a = Bytes::from(LONG); + assert_eq!(LONG, a); + + let b = a.split_to(1); + + assert_eq!(LONG[1..], a); + drop(b); +} + +#[test] +#[should_panic] +fn split_to_oob() { + let mut hello = Bytes::from(&b"helloworld"[..]); + let _ = hello.split_to(33); +} + +#[test] +#[should_panic] +fn split_to_oob_mut() { + let mut hello = BytesMut::from(&b"helloworld"[..]); + let _ = hello.split_to(33); +} + +#[test] +#[should_panic] +fn split_to_uninitialized() { + let mut bytes = BytesMut::with_capacity(1024); + let _other = bytes.split_to(128); +} + +#[test] +fn split_off_to_at_gt_len() { + fn make_bytes() -> Bytes { + let mut bytes = BytesMut::with_capacity(100); + bytes.put_slice(&[10, 20, 30, 40]); + bytes.freeze() + } + + use std::panic; + + let _ = make_bytes().split_to(4); + let _ = make_bytes().split_off(4); + + assert!(panic::catch_unwind(move || { + let _ = make_bytes().split_to(5); + }) + .is_err()); + + assert!(panic::catch_unwind(move || { + let _ = make_bytes().split_off(5); + }) + .is_err()); +} + +#[test] +fn truncate() { + let s = &b"helloworld"[..]; + let mut hello = Bytes::from(s); + hello.truncate(15); + assert_eq!(hello, s); + hello.truncate(10); + assert_eq!(hello, s); + hello.truncate(5); + assert_eq!(hello, "hello"); +} + +#[test] +fn freeze_clone_shared() { + let s = &b"abcdefgh"[..]; + let b = BytesMut::from(s).split().freeze(); + assert_eq!(b, s); + let c = b.clone(); + assert_eq!(c, s); +} + +#[test] +fn freeze_clone_unique() { + let s = &b"abcdefgh"[..]; + let b = BytesMut::from(s).freeze(); + assert_eq!(b, s); + let c = b.clone(); + assert_eq!(c, s); +} + +#[test] +fn freeze_after_advance() { + let s = &b"abcdefgh"[..]; + let mut b = BytesMut::from(s); + b.advance(1); + assert_eq!(b, s[1..]); + let b = b.freeze(); + // Verify fix for #352. Previously, freeze would ignore the start offset + // for BytesMuts in Vec mode. + assert_eq!(b, s[1..]); +} + +#[test] +fn freeze_after_advance_arc() { + let s = &b"abcdefgh"[..]; + let mut b = BytesMut::from(s); + // Make b Arc + let _ = b.split_to(0); + b.advance(1); + assert_eq!(b, s[1..]); + let b = b.freeze(); + assert_eq!(b, s[1..]); +} + +#[test] +fn freeze_after_split_to() { + let s = &b"abcdefgh"[..]; + let mut b = BytesMut::from(s); + let _ = b.split_to(1); + assert_eq!(b, s[1..]); + let b = b.freeze(); + assert_eq!(b, s[1..]); +} + +#[test] +fn freeze_after_truncate() { + let s = &b"abcdefgh"[..]; + let mut b = BytesMut::from(s); + b.truncate(7); + assert_eq!(b, s[..7]); + let b = b.freeze(); + assert_eq!(b, s[..7]); +} + +#[test] +fn freeze_after_truncate_arc() { + let s = &b"abcdefgh"[..]; + let mut b = BytesMut::from(s); + // Make b Arc + let _ = b.split_to(0); + b.truncate(7); + assert_eq!(b, s[..7]); + let b = b.freeze(); + assert_eq!(b, s[..7]); +} + +#[test] +fn freeze_after_split_off() { + let s = &b"abcdefgh"[..]; + let mut b = BytesMut::from(s); + let _ = b.split_off(7); + assert_eq!(b, s[..7]); + let b = b.freeze(); + assert_eq!(b, s[..7]); +} + +#[test] +fn fns_defined_for_bytes_mut() { + let mut bytes = BytesMut::from(&b"hello world"[..]); + + let _ = bytes.as_ptr(); + let _ = bytes.as_mut_ptr(); + + // Iterator + let v: Vec = bytes.as_ref().iter().cloned().collect(); + assert_eq!(&v[..], bytes); +} + +#[test] +fn reserve_convert() { + // Vec -> Vec + let mut bytes = BytesMut::from(LONG); + bytes.reserve(64); + assert_eq!(bytes.capacity(), LONG.len() + 64); + + // Arc -> Vec + let mut bytes = BytesMut::from(LONG); + let a = bytes.split_to(30); + + bytes.reserve(128); + assert!(bytes.capacity() >= bytes.len() + 128); + + drop(a); +} + +#[test] +fn reserve_growth() { + let mut bytes = BytesMut::with_capacity(64); + bytes.put("hello world".as_bytes()); + let _ = bytes.split(); + + bytes.reserve(65); + assert_eq!(bytes.capacity(), 117); +} + +#[test] +fn reserve_allocates_at_least_original_capacity() { + let mut bytes = BytesMut::with_capacity(1024); + + for i in 0..1020 { + bytes.put_u8(i as u8); + } + + let _other = bytes.split(); + + bytes.reserve(16); + assert_eq!(bytes.capacity(), 1024); +} + +#[test] +#[cfg_attr(miri, ignore)] // Miri is too slow +fn reserve_max_original_capacity_value() { + const SIZE: usize = 128 * 1024; + + let mut bytes = BytesMut::with_capacity(SIZE); + + for _ in 0..SIZE { + bytes.put_u8(0u8); + } + + let _other = bytes.split(); + + bytes.reserve(16); + assert_eq!(bytes.capacity(), 64 * 1024); +} + +#[test] +fn reserve_vec_recycling() { + let mut bytes = BytesMut::with_capacity(16); + assert_eq!(bytes.capacity(), 16); + let addr = bytes.as_ptr() as usize; + bytes.put("0123456789012345".as_bytes()); + assert_eq!(bytes.as_ptr() as usize, addr); + bytes.advance(10); + assert_eq!(bytes.capacity(), 6); + bytes.reserve(8); + assert_eq!(bytes.capacity(), 16); + assert_eq!(bytes.as_ptr() as usize, addr); +} + +#[test] +fn reserve_in_arc_unique_does_not_overallocate() { + let mut bytes = BytesMut::with_capacity(1000); + let _ = bytes.split(); + + // now bytes is Arc and refcount == 1 + + assert_eq!(1000, bytes.capacity()); + bytes.reserve(2001); + assert_eq!(2001, bytes.capacity()); +} + +#[test] +fn reserve_in_arc_unique_doubles() { + let mut bytes = BytesMut::with_capacity(1000); + let _ = bytes.split(); + + // now bytes is Arc and refcount == 1 + + assert_eq!(1000, bytes.capacity()); + bytes.reserve(1001); + 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); + let _copy = bytes.split(); + + // now bytes is Arc and refcount == 2 + + assert_eq!(1000, bytes.capacity()); + bytes.reserve(2001); + 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); + bytes.extend(LONG); + assert_eq!(*bytes, LONG[..]); +} + +#[test] +fn extend_from_slice_mut() { + for &i in &[3, 34] { + let mut bytes = BytesMut::new(); + bytes.extend_from_slice(&LONG[..i]); + bytes.extend_from_slice(&LONG[i..]); + assert_eq!(LONG[..], *bytes); + } +} + +#[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); + let mut long_iter = LONG.iter(); + + // Use iter::from_fn since it doesn't know a size_hint + bytes.extend(std::iter::from_fn(|| long_iter.next())); + assert_eq!(*bytes, LONG[..]); +} + +#[test] +fn from_static() { + let mut a = Bytes::from_static(b"ab"); + let b = a.split_off(1); + + assert_eq!(a, b"a"[..]); + assert_eq!(b, b"b"[..]); +} + +#[test] +fn advance_static() { + let mut a = Bytes::from_static(b"hello world"); + a.advance(6); + assert_eq!(a, &b"world"[..]); +} + +#[test] +fn advance_vec() { + let mut a = Bytes::from(b"hello world boooo yah world zomg wat wat".to_vec()); + a.advance(16); + assert_eq!(a, b"o yah world zomg wat wat"[..]); + + a.advance(4); + assert_eq!(a, b"h world zomg wat wat"[..]); + + a.advance(6); + assert_eq!(a, b"d zomg wat wat"[..]); +} + +#[test] +fn advance_bytes_mut() { + let mut a = BytesMut::from("hello world boooo yah world zomg wat wat"); + a.advance(16); + assert_eq!(a, b"o yah world zomg wat wat"[..]); + + a.advance(4); + assert_eq!(a, b"h world zomg wat wat"[..]); + + // Reserve some space. + a.reserve(1024); + assert_eq!(a, b"h world zomg wat wat"[..]); + + a.advance(6); + assert_eq!(a, b"d zomg wat wat"[..]); +} + +#[test] +#[should_panic] +fn advance_past_len() { + let mut a = BytesMut::from("hello world"); + a.advance(20); +} + +#[test] +// Only run these tests on little endian systems. CI uses qemu for testing +// big endian... and qemu doesn't really support threading all that well. +#[cfg(any(miri, target_endian = "little"))] +fn stress() { + // Tests promoting a buffer from a vec -> shared in a concurrent situation + use std::sync::{Arc, Barrier}; + use std::thread; + + const THREADS: usize = 8; + const ITERS: usize = if cfg!(miri) { 100 } else { 1_000 }; + + for i in 0..ITERS { + let data = [i as u8; 256]; + let buf = Arc::new(Bytes::copy_from_slice(&data[..])); + + let barrier = Arc::new(Barrier::new(THREADS)); + let mut joins = Vec::with_capacity(THREADS); + + for _ in 0..THREADS { + let c = barrier.clone(); + let buf = buf.clone(); + + joins.push(thread::spawn(move || { + c.wait(); + let buf: Bytes = (*buf).clone(); + drop(buf); + })); + } + + for th in joins { + th.join().unwrap(); + } + + assert_eq!(*buf, data[..]); + } +} + +#[test] +fn partial_eq_bytesmut() { + let bytes = Bytes::from(&b"The quick red fox"[..]); + let bytesmut = BytesMut::from(&b"The quick red fox"[..]); + assert!(bytes == bytesmut); + assert!(bytesmut == bytes); + let bytes2 = Bytes::from(&b"Jumped over the lazy brown dog"[..]); + assert!(bytes2 != bytesmut); + assert!(bytesmut != bytes2); +} + +/* +#[test] +fn bytes_unsplit_basic() { + let buf = Bytes::from(&b"aaabbbcccddd"[..]); + + let splitted = buf.split_off(6); + assert_eq!(b"aaabbb", &buf[..]); + assert_eq!(b"cccddd", &splitted[..]); + + buf.unsplit(splitted); + assert_eq!(b"aaabbbcccddd", &buf[..]); +} + +#[test] +fn bytes_unsplit_empty_other() { + let buf = Bytes::from(&b"aaabbbcccddd"[..]); + + // empty other + let other = Bytes::new(); + + buf.unsplit(other); + assert_eq!(b"aaabbbcccddd", &buf[..]); +} + +#[test] +fn bytes_unsplit_empty_self() { + // empty self + let mut buf = Bytes::new(); + + let mut other = Bytes::with_capacity(64); + other.extend_from_slice(b"aaabbbcccddd"); + + buf.unsplit(other); + assert_eq!(b"aaabbbcccddd", &buf[..]); +} + +#[test] +fn bytes_unsplit_arc_different() { + let mut buf = Bytes::with_capacity(64); + buf.extend_from_slice(b"aaaabbbbeeee"); + + buf.split_off(8); //arc + + let mut buf2 = Bytes::with_capacity(64); + buf2.extend_from_slice(b"ccccddddeeee"); + + buf2.split_off(8); //arc + + buf.unsplit(buf2); + assert_eq!(b"aaaabbbbccccdddd", &buf[..]); +} + +#[test] +fn bytes_unsplit_arc_non_contiguous() { + let mut buf = Bytes::with_capacity(64); + buf.extend_from_slice(b"aaaabbbbeeeeccccdddd"); + + let mut buf2 = buf.split_off(8); //arc + + let buf3 = buf2.split_off(4); //arc + + buf.unsplit(buf3); + assert_eq!(b"aaaabbbbccccdddd", &buf[..]); +} + +#[test] +fn bytes_unsplit_two_split_offs() { + let mut buf = Bytes::with_capacity(64); + buf.extend_from_slice(b"aaaabbbbccccdddd"); + + let mut buf2 = buf.split_off(8); //arc + let buf3 = buf2.split_off(4); //arc + + buf2.unsplit(buf3); + buf.unsplit(buf2); + assert_eq!(b"aaaabbbbccccdddd", &buf[..]); +} + +#[test] +fn bytes_unsplit_overlapping_references() { + let mut buf = Bytes::with_capacity(64); + buf.extend_from_slice(b"abcdefghijklmnopqrstuvwxyz"); + let mut buf0010 = buf.slice(0..10); + let buf1020 = buf.slice(10..20); + let buf0515 = buf.slice(5..15); + buf0010.unsplit(buf1020); + assert_eq!(b"abcdefghijklmnopqrst", &buf0010[..]); + assert_eq!(b"fghijklmno", &buf0515[..]); +} +*/ + +#[test] +fn bytes_mut_unsplit_basic() { + let mut buf = BytesMut::with_capacity(64); + buf.extend_from_slice(b"aaabbbcccddd"); + + let splitted = buf.split_off(6); + assert_eq!(b"aaabbb", &buf[..]); + assert_eq!(b"cccddd", &splitted[..]); + + buf.unsplit(splitted); + assert_eq!(b"aaabbbcccddd", &buf[..]); +} + +#[test] +fn bytes_mut_unsplit_empty_other() { + let mut buf = BytesMut::with_capacity(64); + buf.extend_from_slice(b"aaabbbcccddd"); + + // empty other + let other = BytesMut::new(); + + buf.unsplit(other); + assert_eq!(b"aaabbbcccddd", &buf[..]); +} + +#[test] +fn bytes_mut_unsplit_empty_self() { + // empty self + let mut buf = BytesMut::new(); + + let mut other = BytesMut::with_capacity(64); + other.extend_from_slice(b"aaabbbcccddd"); + + buf.unsplit(other); + assert_eq!(b"aaabbbcccddd", &buf[..]); +} + +#[test] +fn bytes_mut_unsplit_other_keeps_capacity() { + let mut buf = BytesMut::with_capacity(64); + buf.extend_from_slice(b"aabb"); + + // non empty other created "from" buf + let mut other = buf.split_off(buf.len()); + other.extend_from_slice(b"ccddee"); + buf.unsplit(other); + + assert_eq!(buf.capacity(), 64); +} + +#[test] +fn bytes_mut_unsplit_empty_other_keeps_capacity() { + let mut buf = BytesMut::with_capacity(64); + buf.extend_from_slice(b"aabbccddee"); + + // empty other created "from" buf + let other = buf.split_off(buf.len()); + buf.unsplit(other); + + assert_eq!(buf.capacity(), 64); +} + +#[test] +fn bytes_mut_unsplit_arc_different() { + let mut buf = BytesMut::with_capacity(64); + buf.extend_from_slice(b"aaaabbbbeeee"); + + let _ = buf.split_off(8); //arc + + let mut buf2 = BytesMut::with_capacity(64); + buf2.extend_from_slice(b"ccccddddeeee"); + + let _ = buf2.split_off(8); //arc + + buf.unsplit(buf2); + assert_eq!(b"aaaabbbbccccdddd", &buf[..]); +} + +#[test] +fn bytes_mut_unsplit_arc_non_contiguous() { + let mut buf = BytesMut::with_capacity(64); + buf.extend_from_slice(b"aaaabbbbeeeeccccdddd"); + + let mut buf2 = buf.split_off(8); //arc + + let buf3 = buf2.split_off(4); //arc + + buf.unsplit(buf3); + assert_eq!(b"aaaabbbbccccdddd", &buf[..]); +} + +#[test] +fn bytes_mut_unsplit_two_split_offs() { + let mut buf = BytesMut::with_capacity(64); + buf.extend_from_slice(b"aaaabbbbccccdddd"); + + let mut buf2 = buf.split_off(8); //arc + let buf3 = buf2.split_off(4); //arc + + buf2.unsplit(buf3); + buf.unsplit(buf2); + assert_eq!(b"aaaabbbbccccdddd", &buf[..]); +} + +#[test] +fn from_iter_no_size_hint() { + use std::iter; + + let mut expect = vec![]; + + let actual: Bytes = iter::repeat(b'x') + .scan(100, |cnt, item| { + if *cnt >= 1 { + *cnt -= 1; + expect.push(item); + Some(item) + } else { + None + } + }) + .collect(); + + assert_eq!(&actual[..], &expect[..]); +} + +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); + assert_eq!(&sub[..], expected); +} + +#[test] +fn slice_ref_works() { + let bytes = Bytes::from(&b"012345678"[..]); + + test_slice_ref(&bytes, 0, 0, b""); + test_slice_ref(&bytes, 0, 3, b"012"); + test_slice_ref(&bytes, 2, 6, b"2345"); + test_slice_ref(&bytes, 7, 9, b"78"); + test_slice_ref(&bytes, 9, 9, b""); +} + +#[test] +fn slice_ref_empty() { + let bytes = Bytes::from(&b""[..]); + let slice = &(bytes.as_ref()[0..0]); + + let sub = bytes.slice_ref(slice); + assert_eq!(&sub[..], b""); +} + +#[test] +fn slice_ref_empty_subslice() { + let bytes = Bytes::from(&b"abcde"[..]); + let subbytes = bytes.slice(0..0); + let slice = &subbytes[..]; + // The `slice` object is derived from the original `bytes` object + // so `slice_ref` should work. + assert_eq!(Bytes::new(), bytes.slice_ref(slice)); +} + +#[test] +#[should_panic] +fn slice_ref_catches_not_a_subset() { + let bytes = Bytes::from(&b"012345678"[..]); + let slice = &b"012345"[0..4]; + + bytes.slice_ref(slice); +} + +#[test] +fn slice_ref_not_an_empty_subset() { + let bytes = Bytes::from(&b"012345678"[..]); + let slice = &b""[0..0]; + + assert_eq!(Bytes::new(), bytes.slice_ref(slice)); +} + +#[test] +fn empty_slice_ref_not_an_empty_subset() { + let bytes = Bytes::new(); + let slice = &b"some other slice"[0..0]; + + assert_eq!(Bytes::new(), bytes.slice_ref(slice)); +} + +#[test] +fn bytes_buf_mut_advance() { + let mut bytes = BytesMut::with_capacity(1024); + + unsafe { + let ptr = bytes.chunk_mut().as_mut_ptr(); + assert_eq!(1024, bytes.chunk_mut().len()); + + bytes.advance_mut(10); + + let next = bytes.chunk_mut().as_mut_ptr(); + assert_eq!(1024 - 10, bytes.chunk_mut().len()); + assert_eq!(ptr.offset(10), next); + + // advance to the end + bytes.advance_mut(1024 - 10); + + // The buffer size is doubled + assert_eq!(1024, bytes.chunk_mut().len()); + } +} + +#[test] +fn bytes_buf_mut_reuse_when_fully_consumed() { + use bytes::{Buf, BytesMut}; + let mut buf = BytesMut::new(); + buf.reserve(8192); + buf.extend_from_slice(&[0u8; 100][..]); + + let p = &buf[0] as *const u8; + buf.advance(100); + + buf.reserve(8192); + buf.extend_from_slice(b" "); + + assert_eq!(&buf[0] as *const u8, p); +} + +#[test] +#[should_panic] +fn bytes_reserve_overflow() { + let mut bytes = BytesMut::with_capacity(1024); + bytes.put_slice(b"hello world"); + + bytes.reserve(usize::MAX); +} + +#[test] +fn bytes_with_capacity_but_empty() { + // See https://github.com/tokio-rs/bytes/issues/340 + 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 new file mode 100644 index 0000000..27ed877 --- /dev/null +++ b/tests/test_bytes_odd_alloc.rs @@ -0,0 +1,97 @@ +//! Test using `Bytes` with an allocator that hands out "odd" pointers for +//! vectors (pointers where the LSB is set). + +#![cfg(not(miri))] // Miri does not support custom allocators (also, Miri is "odd" by default with 50% chance) + +use std::alloc::{GlobalAlloc, Layout, System}; +use std::ptr; + +use bytes::Bytes; + +#[global_allocator] +static ODD: Odd = Odd; + +struct Odd; + +unsafe impl GlobalAlloc for Odd { + unsafe fn alloc(&self, layout: Layout) -> *mut u8 { + if layout.align() == 1 && layout.size() > 0 { + // Allocate slightly bigger so that we can offset the pointer by 1 + let size = layout.size() + 1; + 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.offset(1) + } else { + ptr + } + } else { + System.alloc(layout) + } + } + + unsafe fn dealloc(&self, ptr: *mut u8, layout: Layout) { + if layout.align() == 1 && layout.size() > 0 { + let size = layout.size() + 1; + let new_layout = match Layout::from_size_align(size, 1) { + Ok(layout) => layout, + Err(_err) => std::process::abort(), + }; + System.dealloc(ptr.offset(-1), new_layout); + } else { + System.dealloc(ptr, layout); + } + } +} + +#[test] +fn sanity_check_odd_allocator() { + let vec = vec![33u8; 1024]; + let p = vec.as_ptr() as usize; + assert!(p & 0x1 == 0x1, "{:#b}", p); +} + +#[test] +fn test_bytes_from_vec_drop() { + let vec = vec![33u8; 1024]; + let _b = Bytes::from(vec); +} + +#[test] +fn test_bytes_clone_drop() { + let vec = vec![33u8; 1024]; + 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 new file mode 100644 index 0000000..107e56e --- /dev/null +++ b/tests/test_bytes_vec_alloc.rs @@ -0,0 +1,143 @@ +use std::alloc::{GlobalAlloc, Layout, System}; +use std::ptr::null_mut; +use std::sync::atomic::{AtomicPtr, AtomicUsize, Ordering}; + +use bytes::{Buf, Bytes}; + +#[global_allocator] +static LEDGER: Ledger = Ledger::new(); + +const LEDGER_LENGTH: usize = 2048; + +struct Ledger { + alloc_table: [(AtomicPtr, AtomicUsize); LEDGER_LENGTH], +} + +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; + } + } + } + + 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); + + 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]); + bytes.advance(1); + drop(bytes); +} + +#[test] +fn test_bytes_truncate() { + let mut bytes = Bytes::from(vec![10, 20, 30]); + bytes.truncate(2); + drop(bytes); +} + +#[test] +fn test_bytes_truncate_and_advance() { + let mut bytes = Bytes::from(vec![10, 20, 30]); + bytes.truncate(2); + 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 new file mode 100644 index 0000000..cfda6b8 --- /dev/null +++ b/tests/test_chain.rs @@ -0,0 +1,177 @@ +#![warn(rust_2018_idioms)] + +use bytes::{Buf, BufMut, Bytes}; +#[cfg(feature = "std")] +use std::io::IoSlice; + +#[test] +fn collect_two_bufs() { + let a = Bytes::from(&b"hello"[..]); + let b = Bytes::from(&b"world"[..]); + + let res = a.chain(b).copy_to_bytes(10); + assert_eq!(res, &b"helloworld"[..]); +} + +#[test] +fn writing_chained() { + let mut a = [0u8; 64]; + let mut b = [0u8; 64]; + + { + let mut buf = (&mut a[..]).chain_mut(&mut b[..]); + + for i in 0u8..128 { + buf.put_u8(i); + } + } + + for i in 0..64 { + let expect = i as u8; + assert_eq!(expect, a[i]); + assert_eq!(expect + 64, b[i]); + } +} + +#[test] +fn iterating_two_bufs() { + let a = Bytes::from(&b"hello"[..]); + let b = Bytes::from(&b"world"[..]); + + let res: Vec = a.chain(b).into_iter().collect(); + assert_eq!(res, &b"helloworld"[..]); +} + +#[cfg(feature = "std")] +#[test] +fn vectored_read() { + let a = Bytes::from(&b"hello"[..]); + let b = Bytes::from(&b"world"[..]); + + let mut buf = a.chain(b); + + { + let b1: &[u8] = &mut []; + let b2: &[u8] = &mut []; + let b3: &[u8] = &mut []; + let b4: &[u8] = &mut []; + let mut iovecs = [ + IoSlice::new(b1), + IoSlice::new(b2), + IoSlice::new(b3), + IoSlice::new(b4), + ]; + + assert_eq!(2, buf.chunks_vectored(&mut iovecs)); + assert_eq!(iovecs[0][..], b"hello"[..]); + assert_eq!(iovecs[1][..], b"world"[..]); + assert_eq!(iovecs[2][..], b""[..]); + assert_eq!(iovecs[3][..], b""[..]); + } + + buf.advance(2); + + { + let b1: &[u8] = &mut []; + let b2: &[u8] = &mut []; + let b3: &[u8] = &mut []; + let b4: &[u8] = &mut []; + let mut iovecs = [ + IoSlice::new(b1), + IoSlice::new(b2), + IoSlice::new(b3), + IoSlice::new(b4), + ]; + + assert_eq!(2, buf.chunks_vectored(&mut iovecs)); + assert_eq!(iovecs[0][..], b"llo"[..]); + assert_eq!(iovecs[1][..], b"world"[..]); + assert_eq!(iovecs[2][..], b""[..]); + assert_eq!(iovecs[3][..], b""[..]); + } + + buf.advance(3); + + { + let b1: &[u8] = &mut []; + let b2: &[u8] = &mut []; + let b3: &[u8] = &mut []; + let b4: &[u8] = &mut []; + let mut iovecs = [ + IoSlice::new(b1), + IoSlice::new(b2), + IoSlice::new(b3), + IoSlice::new(b4), + ]; + + assert_eq!(1, buf.chunks_vectored(&mut iovecs)); + assert_eq!(iovecs[0][..], b"world"[..]); + assert_eq!(iovecs[1][..], b""[..]); + assert_eq!(iovecs[2][..], b""[..]); + assert_eq!(iovecs[3][..], b""[..]); + } + + buf.advance(3); + + { + let b1: &[u8] = &mut []; + let b2: &[u8] = &mut []; + let b3: &[u8] = &mut []; + let b4: &[u8] = &mut []; + let mut iovecs = [ + IoSlice::new(b1), + IoSlice::new(b2), + IoSlice::new(b3), + IoSlice::new(b4), + ]; + + assert_eq!(1, buf.chunks_vectored(&mut iovecs)); + assert_eq!(iovecs[0][..], b"ld"[..]); + assert_eq!(iovecs[1][..], b""[..]); + assert_eq!(iovecs[2][..], b""[..]); + assert_eq!(iovecs[3][..], b""[..]); + } +} + +#[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"); + let mut cd = Bytes::copy_from_slice(b"cd"); + let ab_ptr = ab.as_ptr(); + let cd_ptr = cd.as_ptr(); + let mut chain = (&mut ab).chain(&mut cd); + let a = chain.copy_to_bytes(1); + let bc = chain.copy_to_bytes(2); + let d = chain.copy_to_bytes(1); + + assert_eq!(Bytes::copy_from_slice(b"a"), a); + assert_eq!(Bytes::copy_from_slice(b"bc"), bc); + assert_eq!(Bytes::copy_from_slice(b"d"), d); + + // assert `get_bytes` did not allocate + assert_eq!(ab_ptr, a.as_ptr()); + // assert `get_bytes` did not allocate + assert_eq!(cd_ptr.wrapping_offset(1), d.as_ptr()); +} diff --git a/tests/test_debug.rs b/tests/test_debug.rs new file mode 100644 index 0000000..08d2f25 --- /dev/null +++ b/tests/test_debug.rs @@ -0,0 +1,35 @@ +#![warn(rust_2018_idioms)] + +use bytes::Bytes; + +#[test] +fn fmt() { + let vec: Vec<_> = (0..0x100).map(|b| b as u8).collect(); + + let expected = "b\"\ + \\0\\x01\\x02\\x03\\x04\\x05\\x06\\x07\ + \\x08\\t\\n\\x0b\\x0c\\r\\x0e\\x0f\ + \\x10\\x11\\x12\\x13\\x14\\x15\\x16\\x17\ + \\x18\\x19\\x1a\\x1b\\x1c\\x1d\\x1e\\x1f\ + \x20!\\\"#$%&'()*+,-./0123456789:;<=>?\ + @ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\\\]^_\ + `abcdefghijklmnopqrstuvwxyz{|}~\\x7f\ + \\x80\\x81\\x82\\x83\\x84\\x85\\x86\\x87\ + \\x88\\x89\\x8a\\x8b\\x8c\\x8d\\x8e\\x8f\ + \\x90\\x91\\x92\\x93\\x94\\x95\\x96\\x97\ + \\x98\\x99\\x9a\\x9b\\x9c\\x9d\\x9e\\x9f\ + \\xa0\\xa1\\xa2\\xa3\\xa4\\xa5\\xa6\\xa7\ + \\xa8\\xa9\\xaa\\xab\\xac\\xad\\xae\\xaf\ + \\xb0\\xb1\\xb2\\xb3\\xb4\\xb5\\xb6\\xb7\ + \\xb8\\xb9\\xba\\xbb\\xbc\\xbd\\xbe\\xbf\ + \\xc0\\xc1\\xc2\\xc3\\xc4\\xc5\\xc6\\xc7\ + \\xc8\\xc9\\xca\\xcb\\xcc\\xcd\\xce\\xcf\ + \\xd0\\xd1\\xd2\\xd3\\xd4\\xd5\\xd6\\xd7\ + \\xd8\\xd9\\xda\\xdb\\xdc\\xdd\\xde\\xdf\ + \\xe0\\xe1\\xe2\\xe3\\xe4\\xe5\\xe6\\xe7\ + \\xe8\\xe9\\xea\\xeb\\xec\\xed\\xee\\xef\ + \\xf0\\xf1\\xf2\\xf3\\xf4\\xf5\\xf6\\xf7\ + \\xf8\\xf9\\xfa\\xfb\\xfc\\xfd\\xfe\\xff\""; + + assert_eq!(expected, format!("{:?}", Bytes::from(vec))); +} diff --git a/tests/test_iter.rs b/tests/test_iter.rs new file mode 100644 index 0000000..a5bfddd --- /dev/null +++ b/tests/test_iter.rs @@ -0,0 +1,21 @@ +#![warn(rust_2018_idioms)] + +use bytes::Bytes; + +#[test] +fn iter_len() { + let buf = Bytes::from_static(b"hello world"); + let iter = buf.iter(); + + assert_eq!(iter.size_hint(), (11, Some(11))); + assert_eq!(iter.len(), 11); +} + +#[test] +fn empty_iter_len() { + let buf = Bytes::from_static(b""); + let iter = buf.iter(); + + assert_eq!(iter.size_hint(), (0, Some(0))); + assert_eq!(iter.len(), 0); +} diff --git a/tests/test_reader.rs b/tests/test_reader.rs new file mode 100644 index 0000000..897aff6 --- /dev/null +++ b/tests/test_reader.rs @@ -0,0 +1,29 @@ +#![warn(rust_2018_idioms)] +#![cfg(feature = "std")] + +use std::io::{BufRead, Read}; + +use bytes::Buf; + +#[test] +fn read() { + let buf1 = &b"hello "[..]; + let buf2 = &b"world"[..]; + let buf = Buf::chain(buf1, buf2); // Disambiguate with Read::chain + let mut buffer = Vec::new(); + buf.reader().read_to_end(&mut buffer).unwrap(); + assert_eq!(b"hello world", &buffer[..]); +} + +#[test] +fn buf_read() { + let buf1 = &b"hell"[..]; + let buf2 = &b"o\nworld"[..]; + let mut reader = Buf::chain(buf1, buf2).reader(); + let mut line = String::new(); + reader.read_line(&mut line).unwrap(); + assert_eq!("hello\n", &line); + line.clear(); + reader.read_line(&mut line).unwrap(); + assert_eq!("world", &line); +} diff --git a/tests/test_serde.rs b/tests/test_serde.rs new file mode 100644 index 0000000..cf4aeff --- /dev/null +++ b/tests/test_serde.rs @@ -0,0 +1,20 @@ +#![cfg(feature = "serde")] +#![warn(rust_2018_idioms)] + +use serde_test::{assert_tokens, Token}; + +#[test] +fn test_ser_de_empty() { + let b = bytes::Bytes::new(); + assert_tokens(&b, &[Token::Bytes(b"")]); + let b = bytes::BytesMut::with_capacity(0); + assert_tokens(&b, &[Token::Bytes(b"")]); +} + +#[test] +fn test_ser_de() { + let b = bytes::Bytes::from(&b"bytes"[..]); + assert_tokens(&b, &[Token::Bytes(b"bytes")]); + let b = bytes::BytesMut::from(&b"bytes"[..]); + assert_tokens(&b, &[Token::Bytes(b"bytes")]); +} diff --git a/tests/test_take.rs b/tests/test_take.rs new file mode 100644 index 0000000..51df91d --- /dev/null +++ b/tests/test_take.rs @@ -0,0 +1,32 @@ +#![warn(rust_2018_idioms)] + +use bytes::buf::Buf; +use bytes::Bytes; + +#[test] +fn long_take() { + // Tests that get a take with a size greater than the buffer length will not + // overrun the buffer. Regression test for #138. + let buf = b"hello world".take(100); + assert_eq!(11, buf.remaining()); + assert_eq!(b"hello world", buf.chunk()); +} + +#[test] +fn take_copy_to_bytes() { + let mut abcd = Bytes::copy_from_slice(b"abcd"); + let abcd_ptr = abcd.as_ptr(); + let mut take = (&mut abcd).take(2); + let a = take.copy_to_bytes(1); + assert_eq!(Bytes::copy_from_slice(b"a"), a); + // assert `to_bytes` did not allocate + assert_eq!(abcd_ptr, a.as_ptr()); + assert_eq!(Bytes::copy_from_slice(b"bcd"), abcd); +} + +#[test] +#[should_panic] +fn take_copy_to_bytes_panics() { + let abcd = Bytes::copy_from_slice(b"abcd"); + abcd.take(2).copy_to_bytes(3); +} -- 2.7.4