From 8cdfa445d6629ffef4cb84967ff7017654045bc2 Mon Sep 17 00:00:00 2001 From: mo khan Date: Wed, 2 Jul 2025 18:36:06 -0600 Subject: chore: add vendor directory --- vendor/bytes/src/buf/buf_impl.rs | 2962 ++++++++++++++++++++++++++++++++++ vendor/bytes/src/buf/buf_mut.rs | 1671 +++++++++++++++++++ vendor/bytes/src/buf/chain.rs | 240 +++ vendor/bytes/src/buf/iter.rs | 127 ++ vendor/bytes/src/buf/limit.rs | 75 + vendor/bytes/src/buf/mod.rs | 39 + vendor/bytes/src/buf/reader.rs | 81 + vendor/bytes/src/buf/take.rs | 204 +++ vendor/bytes/src/buf/uninit_slice.rs | 257 +++ vendor/bytes/src/buf/vec_deque.rs | 40 + vendor/bytes/src/buf/writer.rs | 88 + vendor/bytes/src/bytes.rs | 1680 +++++++++++++++++++ vendor/bytes/src/bytes_mut.rs | 1921 ++++++++++++++++++++++ vendor/bytes/src/fmt/debug.rs | 40 + vendor/bytes/src/fmt/hex.rs | 27 + vendor/bytes/src/fmt/mod.rs | 15 + vendor/bytes/src/lib.rs | 199 +++ vendor/bytes/src/loom.rs | 33 + vendor/bytes/src/serde.rs | 89 + 19 files changed, 9788 insertions(+) create mode 100644 vendor/bytes/src/buf/buf_impl.rs create mode 100644 vendor/bytes/src/buf/buf_mut.rs create mode 100644 vendor/bytes/src/buf/chain.rs create mode 100644 vendor/bytes/src/buf/iter.rs create mode 100644 vendor/bytes/src/buf/limit.rs create mode 100644 vendor/bytes/src/buf/mod.rs create mode 100644 vendor/bytes/src/buf/reader.rs create mode 100644 vendor/bytes/src/buf/take.rs create mode 100644 vendor/bytes/src/buf/uninit_slice.rs create mode 100644 vendor/bytes/src/buf/vec_deque.rs create mode 100644 vendor/bytes/src/buf/writer.rs create mode 100644 vendor/bytes/src/bytes.rs create mode 100644 vendor/bytes/src/bytes_mut.rs create mode 100644 vendor/bytes/src/fmt/debug.rs create mode 100644 vendor/bytes/src/fmt/hex.rs create mode 100644 vendor/bytes/src/fmt/mod.rs create mode 100644 vendor/bytes/src/lib.rs create mode 100644 vendor/bytes/src/loom.rs create mode 100644 vendor/bytes/src/serde.rs (limited to 'vendor/bytes/src') diff --git a/vendor/bytes/src/buf/buf_impl.rs b/vendor/bytes/src/buf/buf_impl.rs new file mode 100644 index 00000000..192034fb --- /dev/null +++ b/vendor/bytes/src/buf/buf_impl.rs @@ -0,0 +1,2962 @@ +#[cfg(feature = "std")] +use crate::buf::{reader, Reader}; +use crate::buf::{take, Chain, Take}; +#[cfg(feature = "std")] +use crate::{min_u64_usize, saturating_sub_usize_u64}; +use crate::{panic_advance, panic_does_not_fit, TryGetError}; + +#[cfg(feature = "std")] +use std::io::IoSlice; + +use alloc::boxed::Box; + +macro_rules! buf_try_get_impl { + ($this:ident, $typ:tt::$conv:tt) => {{ + const SIZE: usize = core::mem::size_of::<$typ>(); + + if $this.remaining() < SIZE { + return Err(TryGetError { + requested: SIZE, + available: $this.remaining(), + }); + } + + // 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 Ok(ret); + } else { + // if not we copy the bytes in a temp buffer then convert + let mut buf = [0; SIZE]; + $this.copy_to_slice(&mut buf); // (do the advance) + return Ok($typ::$conv(buf)); + } + }}; + (le => $this:ident, $typ:tt, $len_to_read:expr) => {{ + const SIZE: usize = core::mem::size_of::<$typ>(); + + // 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; SIZE]; + + let subslice = match buf.get_mut(..$len_to_read) { + Some(subslice) => subslice, + None => panic_does_not_fit(SIZE, $len_to_read), + }; + + $this.try_copy_to_slice(subslice)?; + return Ok($typ::from_le_bytes(buf)); + }}; + (be => $this:ident, $typ:tt, $len_to_read:expr) => {{ + const SIZE: usize = core::mem::size_of::<$typ>(); + + let slice_at = match SIZE.checked_sub($len_to_read) { + Some(slice_at) => slice_at, + None => panic_does_not_fit(SIZE, $len_to_read), + }; + + let mut buf = [0; SIZE]; + $this.try_copy_to_slice(&mut buf[slice_at..])?; + return Ok($typ::from_be_bytes(buf)); + }}; +} + +macro_rules! buf_get_impl { + ($this:ident, $typ:tt::$conv:tt) => {{ + return (|| buf_try_get_impl!($this, $typ::$conv))() + .unwrap_or_else(|error| panic_advance(&error)); + }}; + (le => $this:ident, $typ:tt, $len_to_read:expr) => {{ + return (|| buf_try_get_impl!(le => $this, $typ, $len_to_read))() + .unwrap_or_else(|error| panic_advance(&error)); + }}; + (be => $this:ident, $typ:tt, $len_to_read:expr) => {{ + return (|| buf_try_get_impl!(be => $this, $typ, $len_to_read))() + .unwrap_or_else(|error| panic_advance(&error)); + }}; +} + +// https://en.wikipedia.org/wiki/Sign_extension +fn sign_extend(val: u64, nbytes: usize) -> i64 { + let shift = (8 - nbytes) * 8; + (val << shift) as i64 >> shift +} + +/// 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 a 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. `chunk()` should return an empty + /// slice **if and only if** `remaining()` returns 0. In other words, + /// `chunk()` returning an empty slice implies that `remaining()` will + /// return 0 and `remaining()` returning 0 implies that `chunk()` will + /// 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 written to `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. The return value is the number of + /// slices written to `dst`. If `Buf::remaining()` is non-zero, then this + /// writes at least one non-empty slice to `dst`. + /// + /// 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]) { + self.try_copy_to_slice(dst) + .unwrap_or_else(|error| panic_advance(&error)); + } + + /// 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 { + if self.remaining() < 1 { + panic_advance(&TryGetError { + requested: 1, + available: 0, + }) + } + 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 { + if self.remaining() < 1 { + panic_advance(&TryGetError { + requested: 1, + available: 0, + }); + } + 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`, or + /// if `nbytes` is greater than 8. + 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`, or + /// if `nbytes` is greater than 8. + 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`, or + /// if `nbytes` is greater than 8. + 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`, or + /// if `nbytes` is greater than 8. + fn get_int(&mut self, nbytes: usize) -> i64 { + sign_extend(self.get_uint(nbytes), 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`, or + /// if `nbytes` is greater than 8. + fn get_int_le(&mut self, nbytes: usize) -> i64 { + sign_extend(self.get_uint_le(nbytes), 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`, or + /// if `nbytes` is greater than 8. + 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()) + } + + /// 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()) + } + + /// 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()) + } + + /// 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()) + } + + /// 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()) + } + + /// 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()) + } + + /// 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`. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"hello world"[..]; + /// let mut dst = [0; 5]; + /// + /// assert_eq!(Ok(()), buf.try_copy_to_slice(&mut dst)); + /// assert_eq!(&b"hello"[..], &dst); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"hello world"[..]; + /// let mut dst = [0; 12]; + /// + /// assert_eq!(Err(TryGetError{requested: 12, available: 11}), buf.try_copy_to_slice(&mut dst)); + /// assert_eq!(11, buf.remaining()); + /// ``` + fn try_copy_to_slice(&mut self, mut dst: &mut [u8]) -> Result<(), TryGetError> { + if self.remaining() < dst.len() { + return Err(TryGetError { + requested: dst.len(), + available: self.remaining(), + }); + } + + while !dst.is_empty() { + let src = self.chunk(); + let cnt = usize::min(src.len(), dst.len()); + + dst[..cnt].copy_from_slice(&src[..cnt]); + dst = &mut dst[cnt..]; + + self.advance(cnt); + } + Ok(()) + } + + /// Gets an unsigned 8 bit integer from `self`. + /// + /// The current position is advanced by 1. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x08 hello"[..]; + /// assert_eq!(Ok(0x08_u8), buf.try_get_u8()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b""[..]; + /// assert_eq!(Err(TryGetError{requested: 1, available: 0}), buf.try_get_u8()); + /// ``` + fn try_get_u8(&mut self) -> Result { + if self.remaining() < 1 { + return Err(TryGetError { + requested: 1, + available: self.remaining(), + }); + } + let ret = self.chunk()[0]; + self.advance(1); + Ok(ret) + } + + /// Gets a signed 8 bit integer from `self`. + /// + /// The current position is advanced by 1. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x08 hello"[..]; + /// assert_eq!(Ok(0x08_i8), buf.try_get_i8()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b""[..]; + /// assert_eq!(Err(TryGetError{requested: 1, available: 0}), buf.try_get_i8()); + /// ``` + fn try_get_i8(&mut self) -> Result { + if self.remaining() < 1 { + return Err(TryGetError { + requested: 1, + available: self.remaining(), + }); + } + let ret = self.chunk()[0] as i8; + self.advance(1); + Ok(ret) + } + + /// Gets an unsigned 16 bit integer from `self` in big-endian byte order. + /// + /// The current position is advanced by 2. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x08\x09 hello"[..]; + /// assert_eq!(Ok(0x0809_u16), buf.try_get_u16()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x08"[..]; + /// assert_eq!(Err(TryGetError{requested: 2, available: 1}), buf.try_get_u16()); + /// assert_eq!(1, buf.remaining()); + /// ``` + fn try_get_u16(&mut self) -> Result { + buf_try_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. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x09\x08 hello"[..]; + /// assert_eq!(Ok(0x0809_u16), buf.try_get_u16_le()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x08"[..]; + /// assert_eq!(Err(TryGetError{requested: 2, available: 1}), buf.try_get_u16_le()); + /// assert_eq!(1, buf.remaining()); + /// ``` + fn try_get_u16_le(&mut self) -> Result { + buf_try_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. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # 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!(Ok(0x0809_u16), buf.try_get_u16_ne()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x08"[..]; + /// assert_eq!(Err(TryGetError{requested: 2, available: 1}), buf.try_get_u16_ne()); + /// assert_eq!(1, buf.remaining()); + /// ``` + fn try_get_u16_ne(&mut self) -> Result { + buf_try_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. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x08\x09 hello"[..]; + /// assert_eq!(Ok(0x0809_i16), buf.try_get_i16()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x08"[..]; + /// assert_eq!(Err(TryGetError{requested: 2, available: 1}), buf.try_get_i16()); + /// assert_eq!(1, buf.remaining()); + /// ``` + fn try_get_i16(&mut self) -> Result { + buf_try_get_impl!(self, i16::from_be_bytes) + } + + /// Gets an signed 16 bit integer from `self` in little-endian byte order. + /// + /// The current position is advanced by 2. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x09\x08 hello"[..]; + /// assert_eq!(Ok(0x0809_i16), buf.try_get_i16_le()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x08"[..]; + /// assert_eq!(Err(TryGetError{requested: 2, available: 1}), buf.try_get_i16_le()); + /// assert_eq!(1, buf.remaining()); + /// ``` + fn try_get_i16_le(&mut self) -> Result { + buf_try_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. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # 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!(Ok(0x0809_i16), buf.try_get_i16_ne()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x08"[..]; + /// assert_eq!(Err(TryGetError{requested: 2, available: 1}), buf.try_get_i16_ne()); + /// assert_eq!(1, buf.remaining()); + /// ``` + fn try_get_i16_ne(&mut self) -> Result { + buf_try_get_impl!(self, i16::from_ne_bytes) + } + + /// Gets an unsigned 32 bit integer from `self` in big-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x08\x09\xA0\xA1 hello"[..]; + /// assert_eq!(Ok(0x0809A0A1), buf.try_get_u32()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x01\x02\x03"[..]; + /// assert_eq!(Err(TryGetError{requested: 4, available: 3}), buf.try_get_u32()); + /// assert_eq!(3, buf.remaining()); + /// ``` + fn try_get_u32(&mut self) -> Result { + buf_try_get_impl!(self, u32::from_be_bytes) + } + + /// Gets an unsigned 32 bit integer from `self` in little-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\xA1\xA0\x09\x08 hello"[..]; + /// assert_eq!(Ok(0x0809A0A1_u32), buf.try_get_u32_le()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x08\x09\xA0"[..]; + /// assert_eq!(Err(TryGetError{requested: 4, available: 3}), buf.try_get_u32_le()); + /// assert_eq!(3, buf.remaining()); + /// ``` + fn try_get_u32_le(&mut self) -> Result { + buf_try_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. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # 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!(Ok(0x0809A0A1_u32), buf.try_get_u32_ne()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x08\x09\xA0"[..]; + /// assert_eq!(Err(TryGetError{requested: 4, available: 3}), buf.try_get_u32_ne()); + /// assert_eq!(3, buf.remaining()); + /// ``` + fn try_get_u32_ne(&mut self) -> Result { + buf_try_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. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x08\x09\xA0\xA1 hello"[..]; + /// assert_eq!(Ok(0x0809A0A1_i32), buf.try_get_i32()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x01\x02\x03"[..]; + /// assert_eq!(Err(TryGetError{requested: 4, available: 3}), buf.try_get_i32()); + /// assert_eq!(3, buf.remaining()); + /// ``` + fn try_get_i32(&mut self) -> Result { + buf_try_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. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\xA1\xA0\x09\x08 hello"[..]; + /// assert_eq!(Ok(0x0809A0A1_i32), buf.try_get_i32_le()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x08\x09\xA0"[..]; + /// assert_eq!(Err(TryGetError{requested: 4, available: 3}), buf.try_get_i32_le()); + /// assert_eq!(3, buf.remaining()); + /// ``` + fn try_get_i32_le(&mut self) -> Result { + buf_try_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. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # 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!(Ok(0x0809A0A1_i32), buf.try_get_i32_ne()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x08\x09\xA0"[..]; + /// assert_eq!(Err(TryGetError{requested: 4, available: 3}), buf.try_get_i32_ne()); + /// assert_eq!(3, buf.remaining()); + /// ``` + fn try_get_i32_ne(&mut self) -> Result { + buf_try_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. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x01\x02\x03\x04\x05\x06\x07\x08 hello"[..]; + /// assert_eq!(Ok(0x0102030405060708_u64), buf.try_get_u64()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x01\x02\x03\x04\x05\x06\x07"[..]; + /// assert_eq!(Err(TryGetError{requested: 8, available: 7}), buf.try_get_u64()); + /// assert_eq!(7, buf.remaining()); + /// ``` + fn try_get_u64(&mut self) -> Result { + buf_try_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. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x08\x07\x06\x05\x04\x03\x02\x01 hello"[..]; + /// assert_eq!(Ok(0x0102030405060708_u64), buf.try_get_u64_le()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x08\x07\x06\x05\x04\x03\x02"[..]; + /// assert_eq!(Err(TryGetError{requested: 8, available: 7}), buf.try_get_u64_le()); + /// assert_eq!(7, buf.remaining()); + /// ``` + fn try_get_u64_le(&mut self) -> Result { + buf_try_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. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # 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!(Ok(0x0102030405060708_u64), buf.try_get_u64_ne()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x01\x02\x03\x04\x05\x06\x07"[..]; + /// assert_eq!(Err(TryGetError{requested: 8, available: 7}), buf.try_get_u64_ne()); + /// assert_eq!(7, buf.remaining()); + /// ``` + fn try_get_u64_ne(&mut self) -> Result { + buf_try_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. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x01\x02\x03\x04\x05\x06\x07\x08 hello"[..]; + /// assert_eq!(Ok(0x0102030405060708_i64), buf.try_get_i64()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x01\x02\x03\x04\x05\x06\x07"[..]; + /// assert_eq!(Err(TryGetError{requested: 8, available: 7}), buf.try_get_i64()); + /// assert_eq!(7, buf.remaining()); + /// ``` + fn try_get_i64(&mut self) -> Result { + buf_try_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. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x08\x07\x06\x05\x04\x03\x02\x01 hello"[..]; + /// assert_eq!(Ok(0x0102030405060708_i64), buf.try_get_i64_le()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x08\x07\x06\x05\x04\x03\x02"[..]; + /// assert_eq!(Err(TryGetError{requested: 8, available: 7}), buf.try_get_i64_le()); + /// assert_eq!(7, buf.remaining()); + /// ``` + fn try_get_i64_le(&mut self) -> Result { + buf_try_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. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # 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!(Ok(0x0102030405060708_i64), buf.try_get_i64_ne()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x01\x02\x03\x04\x05\x06\x07"[..]; + /// assert_eq!(Err(TryGetError{requested: 8, available: 7}), buf.try_get_i64_ne()); + /// assert_eq!(7, buf.remaining()); + /// ``` + fn try_get_i64_ne(&mut self) -> Result { + buf_try_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. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # 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!(Ok(0x01020304050607080910111213141516_u128), buf.try_get_u128()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15"[..]; + /// assert_eq!(Err(TryGetError{requested: 16, available: 15}), buf.try_get_u128()); + /// assert_eq!(15, buf.remaining()); + /// ``` + fn try_get_u128(&mut self) -> Result { + buf_try_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. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # 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!(Ok(0x01020304050607080910111213141516_u128), buf.try_get_u128_le()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02"[..]; + /// assert_eq!(Err(TryGetError{requested: 16, available: 15}), buf.try_get_u128_le()); + /// assert_eq!(15, buf.remaining()); + /// ``` + fn try_get_u128_le(&mut self) -> Result { + buf_try_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. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # 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!(Ok(0x01020304050607080910111213141516_u128), buf.try_get_u128_ne()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15"[..]; + /// assert_eq!(Err(TryGetError{requested: 16, available: 15}), buf.try_get_u128_ne()); + /// assert_eq!(15, buf.remaining()); + /// ``` + fn try_get_u128_ne(&mut self) -> Result { + buf_try_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. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # 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!(Ok(0x01020304050607080910111213141516_i128), buf.try_get_i128()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15"[..]; + /// assert_eq!(Err(TryGetError{requested: 16, available: 15}), buf.try_get_i128()); + /// assert_eq!(15, buf.remaining()); + /// ``` + fn try_get_i128(&mut self) -> Result { + buf_try_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. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # 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!(Ok(0x01020304050607080910111213141516_i128), buf.try_get_i128_le()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02"[..]; + /// assert_eq!(Err(TryGetError{requested: 16, available: 15}), buf.try_get_i128_le()); + /// assert_eq!(15, buf.remaining()); + /// ``` + fn try_get_i128_le(&mut self) -> Result { + buf_try_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. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # 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!(Ok(0x01020304050607080910111213141516_i128), buf.try_get_i128_ne()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15"[..]; + /// assert_eq!(Err(TryGetError{requested: 16, available: 15}), buf.try_get_i128_ne()); + /// assert_eq!(15, buf.remaining()); + /// ``` + fn try_get_i128_ne(&mut self) -> Result { + buf_try_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`. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x01\x02\x03 hello"[..]; + /// assert_eq!(Ok(0x010203_u64), buf.try_get_uint(3)); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x01\x02\x03"[..]; + /// assert_eq!(Err(TryGetError{requested: 4, available: 3}), buf.try_get_uint(4)); + /// assert_eq!(3, buf.remaining()); + /// ``` + /// + /// # Panics + /// + /// This function panics if `nbytes` > 8. + fn try_get_uint(&mut self, nbytes: usize) -> Result { + buf_try_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`. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x03\x02\x01 hello"[..]; + /// assert_eq!(Ok(0x010203_u64), buf.try_get_uint_le(3)); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x01\x02\x03"[..]; + /// assert_eq!(Err(TryGetError{requested: 4, available: 3}), buf.try_get_uint_le(4)); + /// assert_eq!(3, buf.remaining()); + /// ``` + /// + /// # Panics + /// + /// This function panics if `nbytes` > 8. + fn try_get_uint_le(&mut self, nbytes: usize) -> Result { + buf_try_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`. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # 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!(Ok(0x010203_u64), buf.try_get_uint_ne(3)); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf: &[u8] = match cfg!(target_endian = "big") { + /// true => b"\x01\x02\x03", + /// false => b"\x03\x02\x01", + /// }; + /// assert_eq!(Err(TryGetError{requested: 4, available: 3}), buf.try_get_uint_ne(4)); + /// assert_eq!(3, buf.remaining()); + /// ``` + /// + /// # Panics + /// + /// This function panics if `nbytes` is greater than 8. + fn try_get_uint_ne(&mut self, nbytes: usize) -> Result { + if cfg!(target_endian = "big") { + self.try_get_uint(nbytes) + } else { + self.try_get_uint_le(nbytes) + } + } + + /// Gets a signed n-byte integer from `self` in big-endian byte order. + /// + /// The current position is advanced by `nbytes`. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x01\x02\x03 hello"[..]; + /// assert_eq!(Ok(0x010203_i64), buf.try_get_int(3)); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x01\x02\x03"[..]; + /// assert_eq!(Err(TryGetError{requested: 4, available: 3}), buf.try_get_int(4)); + /// assert_eq!(3, buf.remaining()); + /// ``` + /// + /// # Panics + /// + /// This function panics if `nbytes` is greater than 8. + fn try_get_int(&mut self, nbytes: usize) -> Result { + buf_try_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`. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x03\x02\x01 hello"[..]; + /// assert_eq!(Ok(0x010203_i64), buf.try_get_int_le(3)); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x01\x02\x03"[..]; + /// assert_eq!(Err(TryGetError{requested: 4, available: 3}), buf.try_get_int_le(4)); + /// assert_eq!(3, buf.remaining()); + /// ``` + /// + /// # Panics + /// + /// This function panics if `nbytes` is greater than 8. + fn try_get_int_le(&mut self, nbytes: usize) -> Result { + buf_try_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`. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # 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!(Ok(0x010203_i64), buf.try_get_int_ne(3)); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf: &[u8] = match cfg!(target_endian = "big") { + /// true => b"\x01\x02\x03", + /// false => b"\x03\x02\x01", + /// }; + /// assert_eq!(Err(TryGetError{requested: 4, available: 3}), buf.try_get_int_ne(4)); + /// assert_eq!(3, buf.remaining()); + /// ``` + /// + /// # Panics + /// + /// This function panics if `nbytes` is greater than 8. + fn try_get_int_ne(&mut self, nbytes: usize) -> Result { + if cfg!(target_endian = "big") { + self.try_get_int(nbytes) + } else { + self.try_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. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x3F\x99\x99\x9A hello"[..]; + /// assert_eq!(1.2f32, buf.get_f32()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x3F\x99\x99"[..]; + /// assert_eq!(Err(TryGetError{requested: 4, available: 3}), buf.try_get_f32()); + /// assert_eq!(3, buf.remaining()); + /// ``` + fn try_get_f32(&mut self) -> Result { + Ok(f32::from_bits(self.try_get_u32()?)) + } + + /// Gets an IEEE754 single-precision (4 bytes) floating point number from + /// `self` in little-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x9A\x99\x99\x3F hello"[..]; + /// assert_eq!(1.2f32, buf.get_f32_le()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x3F\x99\x99"[..]; + /// assert_eq!(Err(TryGetError{requested: 4, available: 3}), buf.try_get_f32_le()); + /// assert_eq!(3, buf.remaining()); + /// ``` + fn try_get_f32_le(&mut self) -> Result { + Ok(f32::from_bits(self.try_get_u32_le()?)) + } + + /// Gets an IEEE754 single-precision (4 bytes) floating point number from + /// `self` in native-endian byte order. + /// + /// The current position is advanced by 4. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # 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()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x3F\x99\x99"[..]; + /// assert_eq!(Err(TryGetError{requested: 4, available: 3}), buf.try_get_f32_ne()); + /// assert_eq!(3, buf.remaining()); + /// ``` + fn try_get_f32_ne(&mut self) -> Result { + Ok(f32::from_bits(self.try_get_u32_ne()?)) + } + + /// Gets an IEEE754 double-precision (8 bytes) floating point number from + /// `self` in big-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # Examples + /// + /// ``` + /// use bytes::Buf; + /// + /// let mut buf = &b"\x3F\xF3\x33\x33\x33\x33\x33\x33 hello"[..]; + /// assert_eq!(1.2f64, buf.get_f64()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x3F\xF3\x33\x33\x33\x33\x33"[..]; + /// assert_eq!(Err(TryGetError{requested: 8, available: 7}), buf.try_get_f64()); + /// assert_eq!(7, buf.remaining()); + /// ``` + fn try_get_f64(&mut self) -> Result { + Ok(f64::from_bits(self.try_get_u64()?)) + } + + /// Gets an IEEE754 double-precision (8 bytes) floating point number from + /// `self` in little-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # 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()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x3F\xF3\x33\x33\x33\x33\x33"[..]; + /// assert_eq!(Err(TryGetError{requested: 8, available: 7}), buf.try_get_f64_le()); + /// assert_eq!(7, buf.remaining()); + /// ``` + fn try_get_f64_le(&mut self) -> Result { + Ok(f64::from_bits(self.try_get_u64_le()?)) + } + + /// Gets an IEEE754 double-precision (8 bytes) floating point number from + /// `self` in native-endian byte order. + /// + /// The current position is advanced by 8. + /// + /// Returns `Err(TryGetError)` when there are not enough + /// remaining bytes to read the value. + /// + /// # 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()); + /// assert_eq!(6, buf.remaining()); + /// ``` + /// + /// ``` + /// use bytes::{Buf, TryGetError}; + /// + /// let mut buf = &b"\x3F\xF3\x33\x33\x33\x33\x33"[..]; + /// assert_eq!(Err(TryGetError{requested: 8, available: 7}), buf.try_get_f64_ne()); + /// assert_eq!(7, buf.remaining()); + /// ``` + fn try_get_f64_ne(&mut self) -> Result { + Ok(f64::from_bits(self.try_get_u64_ne()?)) + } + + /// 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"[..]); + /// ``` + /// + /// # Panics + /// + /// This function panics if `len > self.remaining()`. + fn copy_to_bytes(&mut self, len: usize) -> crate::Bytes { + use super::BufMut; + + if self.remaining() < len { + panic_advance(&TryGetError { + requested: len, + available: self.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 { + () => { + #[inline] + fn remaining(&self) -> usize { + (**self).remaining() + } + + #[inline] + fn chunk(&self) -> &[u8] { + (**self).chunk() + } + + #[cfg(feature = "std")] + #[inline] + fn chunks_vectored<'b>(&'b self, dst: &mut [IoSlice<'b>]) -> usize { + (**self).chunks_vectored(dst) + } + + #[inline] + fn advance(&mut self, cnt: usize) { + (**self).advance(cnt) + } + + #[inline] + fn has_remaining(&self) -> bool { + (**self).has_remaining() + } + + #[inline] + fn copy_to_slice(&mut self, dst: &mut [u8]) { + (**self).copy_to_slice(dst) + } + + #[inline] + fn get_u8(&mut self) -> u8 { + (**self).get_u8() + } + + #[inline] + fn get_i8(&mut self) -> i8 { + (**self).get_i8() + } + + #[inline] + fn get_u16(&mut self) -> u16 { + (**self).get_u16() + } + + #[inline] + fn get_u16_le(&mut self) -> u16 { + (**self).get_u16_le() + } + + #[inline] + fn get_u16_ne(&mut self) -> u16 { + (**self).get_u16_ne() + } + + #[inline] + fn get_i16(&mut self) -> i16 { + (**self).get_i16() + } + + #[inline] + fn get_i16_le(&mut self) -> i16 { + (**self).get_i16_le() + } + + #[inline] + fn get_i16_ne(&mut self) -> i16 { + (**self).get_i16_ne() + } + + #[inline] + fn get_u32(&mut self) -> u32 { + (**self).get_u32() + } + + #[inline] + fn get_u32_le(&mut self) -> u32 { + (**self).get_u32_le() + } + + #[inline] + fn get_u32_ne(&mut self) -> u32 { + (**self).get_u32_ne() + } + + #[inline] + fn get_i32(&mut self) -> i32 { + (**self).get_i32() + } + + #[inline] + fn get_i32_le(&mut self) -> i32 { + (**self).get_i32_le() + } + + #[inline] + fn get_i32_ne(&mut self) -> i32 { + (**self).get_i32_ne() + } + + #[inline] + fn get_u64(&mut self) -> u64 { + (**self).get_u64() + } + + #[inline] + fn get_u64_le(&mut self) -> u64 { + (**self).get_u64_le() + } + + #[inline] + fn get_u64_ne(&mut self) -> u64 { + (**self).get_u64_ne() + } + + #[inline] + fn get_i64(&mut self) -> i64 { + (**self).get_i64() + } + + #[inline] + fn get_i64_le(&mut self) -> i64 { + (**self).get_i64_le() + } + + #[inline] + fn get_i64_ne(&mut self) -> i64 { + (**self).get_i64_ne() + } + + #[inline] + fn get_u128(&mut self) -> u128 { + (**self).get_u128() + } + + #[inline] + fn get_u128_le(&mut self) -> u128 { + (**self).get_u128_le() + } + + #[inline] + fn get_u128_ne(&mut self) -> u128 { + (**self).get_u128_ne() + } + + #[inline] + fn get_i128(&mut self) -> i128 { + (**self).get_i128() + } + + #[inline] + fn get_i128_le(&mut self) -> i128 { + (**self).get_i128_le() + } + + #[inline] + fn get_i128_ne(&mut self) -> i128 { + (**self).get_i128_ne() + } + + #[inline] + fn get_uint(&mut self, nbytes: usize) -> u64 { + (**self).get_uint(nbytes) + } + + #[inline] + fn get_uint_le(&mut self, nbytes: usize) -> u64 { + (**self).get_uint_le(nbytes) + } + + #[inline] + fn get_uint_ne(&mut self, nbytes: usize) -> u64 { + (**self).get_uint_ne(nbytes) + } + + #[inline] + fn get_int(&mut self, nbytes: usize) -> i64 { + (**self).get_int(nbytes) + } + + #[inline] + fn get_int_le(&mut self, nbytes: usize) -> i64 { + (**self).get_int_le(nbytes) + } + + #[inline] + fn get_int_ne(&mut self, nbytes: usize) -> i64 { + (**self).get_int_ne(nbytes) + } + + #[inline] + fn get_f32(&mut self) -> f32 { + (**self).get_f32() + } + + #[inline] + fn get_f32_le(&mut self) -> f32 { + (**self).get_f32_le() + } + + #[inline] + fn get_f32_ne(&mut self) -> f32 { + (**self).get_f32_ne() + } + + #[inline] + fn get_f64(&mut self) -> f64 { + (**self).get_f64() + } + + #[inline] + fn get_f64_le(&mut self) -> f64 { + (**self).get_f64_le() + } + + #[inline] + fn get_f64_ne(&mut self) -> f64 { + (**self).get_f64_ne() + } + + #[inline] + fn try_copy_to_slice(&mut self, dst: &mut [u8]) -> Result<(), TryGetError> { + (**self).try_copy_to_slice(dst) + } + + #[inline] + fn try_get_u8(&mut self) -> Result { + (**self).try_get_u8() + } + + #[inline] + fn try_get_i8(&mut self) -> Result { + (**self).try_get_i8() + } + + #[inline] + fn try_get_u16(&mut self) -> Result { + (**self).try_get_u16() + } + + #[inline] + fn try_get_u16_le(&mut self) -> Result { + (**self).try_get_u16_le() + } + + #[inline] + fn try_get_u16_ne(&mut self) -> Result { + (**self).try_get_u16_ne() + } + + #[inline] + fn try_get_i16(&mut self) -> Result { + (**self).try_get_i16() + } + + #[inline] + fn try_get_i16_le(&mut self) -> Result { + (**self).try_get_i16_le() + } + + #[inline] + fn try_get_i16_ne(&mut self) -> Result { + (**self).try_get_i16_ne() + } + + #[inline] + fn try_get_u32(&mut self) -> Result { + (**self).try_get_u32() + } + + #[inline] + fn try_get_u32_le(&mut self) -> Result { + (**self).try_get_u32_le() + } + + #[inline] + fn try_get_u32_ne(&mut self) -> Result { + (**self).try_get_u32_ne() + } + + #[inline] + fn try_get_i32(&mut self) -> Result { + (**self).try_get_i32() + } + + #[inline] + fn try_get_i32_le(&mut self) -> Result { + (**self).try_get_i32_le() + } + + #[inline] + fn try_get_i32_ne(&mut self) -> Result { + (**self).try_get_i32_ne() + } + + #[inline] + fn try_get_u64(&mut self) -> Result { + (**self).try_get_u64() + } + + #[inline] + fn try_get_u64_le(&mut self) -> Result { + (**self).try_get_u64_le() + } + + #[inline] + fn try_get_u64_ne(&mut self) -> Result { + (**self).try_get_u64_ne() + } + + #[inline] + fn try_get_i64(&mut self) -> Result { + (**self).try_get_i64() + } + + #[inline] + fn try_get_i64_le(&mut self) -> Result { + (**self).try_get_i64_le() + } + + #[inline] + fn try_get_i64_ne(&mut self) -> Result { + (**self).try_get_i64_ne() + } + + #[inline] + fn try_get_u128(&mut self) -> Result { + (**self).try_get_u128() + } + + #[inline] + fn try_get_u128_le(&mut self) -> Result { + (**self).try_get_u128_le() + } + + #[inline] + fn try_get_u128_ne(&mut self) -> Result { + (**self).try_get_u128_ne() + } + + #[inline] + fn try_get_i128(&mut self) -> Result { + (**self).try_get_i128() + } + + #[inline] + fn try_get_i128_le(&mut self) -> Result { + (**self).try_get_i128_le() + } + + #[inline] + fn try_get_i128_ne(&mut self) -> Result { + (**self).try_get_i128_ne() + } + + #[inline] + fn try_get_uint(&mut self, nbytes: usize) -> Result { + (**self).try_get_uint(nbytes) + } + + #[inline] + fn try_get_uint_le(&mut self, nbytes: usize) -> Result { + (**self).try_get_uint_le(nbytes) + } + + #[inline] + fn try_get_uint_ne(&mut self, nbytes: usize) -> Result { + (**self).try_get_uint_ne(nbytes) + } + + #[inline] + fn try_get_int(&mut self, nbytes: usize) -> Result { + (**self).try_get_int(nbytes) + } + + #[inline] + fn try_get_int_le(&mut self, nbytes: usize) -> Result { + (**self).try_get_int_le(nbytes) + } + + #[inline] + fn try_get_int_ne(&mut self, nbytes: usize) -> Result { + (**self).try_get_int_ne(nbytes) + } + + #[inline] + fn try_get_f32(&mut self) -> Result { + (**self).try_get_f32() + } + + #[inline] + fn try_get_f32_le(&mut self) -> Result { + (**self).try_get_f32_le() + } + + #[inline] + fn try_get_f32_ne(&mut self) -> Result { + (**self).try_get_f32_ne() + } + + #[inline] + fn try_get_f64(&mut self) -> Result { + (**self).try_get_f64() + } + + #[inline] + fn try_get_f64_le(&mut self) -> Result { + (**self).try_get_f64_le() + } + + #[inline] + fn try_get_f64_ne(&mut self) -> Result { + (**self).try_get_f64_ne() + } + + #[inline] + 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) { + if self.len() < cnt { + panic_advance(&TryGetError { + requested: cnt, + available: self.len(), + }); + } + + *self = &self[cnt..]; + } + + #[inline] + fn copy_to_slice(&mut self, dst: &mut [u8]) { + if self.len() < dst.len() { + panic_advance(&TryGetError { + requested: dst.len(), + available: self.len(), + }); + } + + dst.copy_from_slice(&self[..dst.len()]); + self.advance(dst.len()); + } +} + +#[cfg(feature = "std")] +impl> Buf for std::io::Cursor { + #[inline] + fn remaining(&self) -> usize { + saturating_sub_usize_u64(self.get_ref().as_ref().len(), self.position()) + } + + #[inline] + fn chunk(&self) -> &[u8] { + let slice = self.get_ref().as_ref(); + let pos = min_u64_usize(self.position(), slice.len()); + &slice[pos..] + } + + #[inline] + fn advance(&mut self, cnt: usize) { + let len = self.get_ref().as_ref().len(); + let pos = self.position(); + + // We intentionally allow `cnt == 0` here even if `pos > len`. + let max_cnt = saturating_sub_usize_u64(len, pos); + if cnt > max_cnt { + panic_advance(&TryGetError { + requested: cnt, + available: max_cnt, + }); + } + + // This will not overflow because either `cnt == 0` or the sum is not + // greater than `len`. + self.set_position(pos + cnt 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/vendor/bytes/src/buf/buf_mut.rs b/vendor/bytes/src/buf/buf_mut.rs new file mode 100644 index 00000000..26645c6a --- /dev/null +++ b/vendor/bytes/src/buf/buf_mut.rs @@ -0,0 +1,1671 @@ +use crate::buf::{limit, Chain, Limit, UninitSlice}; +#[cfg(feature = "std")] +use crate::buf::{writer, Writer}; +use crate::{panic_advance, panic_does_not_fit, TryGetError}; + +use core::{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. + /// + /// # Safety + /// + /// The caller must ensure that the next `cnt` bytes of `chunk` are + /// 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()); + /// ``` + #[inline] + 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`. + #[inline] + fn put(&mut self, mut src: T) + where + Self: Sized, + { + if self.remaining_mut() < src.remaining() { + panic_advance(&TryGetError { + requested: src.remaining(), + available: self.remaining_mut(), + }); + } + + while src.has_remaining() { + let s = src.chunk(); + let d = self.chunk_mut(); + let cnt = usize::min(s.len(), d.len()); + + d[..cnt].copy_from_slice(&s[..cnt]); + + // SAFETY: We just initialized `cnt` bytes in `self`. + unsafe { self.advance_mut(cnt) }; + src.advance(cnt); + } + } + + /// 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); + /// ``` + #[inline] + fn put_slice(&mut self, mut src: &[u8]) { + if self.remaining_mut() < src.len() { + panic_advance(&TryGetError { + requested: src.len(), + available: self.remaining_mut(), + }); + } + + while !src.is_empty() { + let dst = self.chunk_mut(); + let cnt = usize::min(src.len(), dst.len()); + + dst[..cnt].copy_from_slice(&src[..cnt]); + src = &src[cnt..]; + + // SAFETY: We just initialized `cnt` bytes in `self`. + 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`. + #[inline] + fn put_bytes(&mut self, val: u8, mut cnt: usize) { + if self.remaining_mut() < cnt { + panic_advance(&TryGetError { + requested: cnt, + available: self.remaining_mut(), + }) + } + + while cnt > 0 { + let dst = self.chunk_mut(); + let dst_len = usize::min(dst.len(), cnt); + // SAFETY: The pointer is valid for `dst_len <= dst.len()` bytes. + unsafe { core::ptr::write_bytes(dst.as_mut_ptr(), val, dst_len) }; + // SAFETY: We just initialized `dst_len` bytes in `self`. + unsafe { self.advance_mut(dst_len) }; + cnt -= dst_len; + } + } + + /// 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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` or if `nbytes` is greater than 8. + #[inline] + fn put_uint(&mut self, n: u64, nbytes: usize) { + let start = match mem::size_of_val(&n).checked_sub(nbytes) { + Some(start) => start, + None => panic_does_not_fit(nbytes, mem::size_of_val(&n)), + }; + + self.put_slice(&n.to_be_bytes()[start..]); + } + + /// 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` or if `nbytes` is greater than 8. + #[inline] + fn put_uint_le(&mut self, n: u64, nbytes: usize) { + let slice = n.to_le_bytes(); + let slice = match slice.get(..nbytes) { + Some(slice) => slice, + None => panic_does_not_fit(nbytes, slice.len()), + }; + + self.put_slice(slice); + } + + /// 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` or if `nbytes` is greater than 8. + #[inline] + 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. + #[inline] + fn put_int(&mut self, n: i64, nbytes: usize) { + let start = match mem::size_of_val(&n).checked_sub(nbytes) { + Some(start) => start, + None => panic_does_not_fit(nbytes, mem::size_of_val(&n)), + }; + + self.put_slice(&n.to_be_bytes()[start..]); + } + + /// 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. + #[inline] + fn put_int_le(&mut self, n: i64, nbytes: usize) { + let slice = n.to_le_bytes(); + let slice = match slice.get(..nbytes) { + Some(slice) => slice, + None => panic_does_not_fit(nbytes, slice.len()), + }; + + self.put_slice(slice); + } + + /// 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. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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`. + #[inline] + 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); + /// ``` + #[inline] + 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")))] + #[inline] + 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"); + /// ``` + #[inline] + fn chain_mut(self, next: U) -> Chain + where + Self: Sized, + { + Chain::new(self, next) + } +} + +macro_rules! deref_forward_bufmut { + () => { + #[inline] + fn remaining_mut(&self) -> usize { + (**self).remaining_mut() + } + + #[inline] + fn chunk_mut(&mut self) -> &mut UninitSlice { + (**self).chunk_mut() + } + + #[inline] + unsafe fn advance_mut(&mut self, cnt: usize) { + (**self).advance_mut(cnt) + } + + #[inline] + fn put_slice(&mut self, src: &[u8]) { + (**self).put_slice(src) + } + + #[inline] + fn put_u8(&mut self, n: u8) { + (**self).put_u8(n) + } + + #[inline] + fn put_i8(&mut self, n: i8) { + (**self).put_i8(n) + } + + #[inline] + fn put_u16(&mut self, n: u16) { + (**self).put_u16(n) + } + + #[inline] + fn put_u16_le(&mut self, n: u16) { + (**self).put_u16_le(n) + } + + #[inline] + fn put_u16_ne(&mut self, n: u16) { + (**self).put_u16_ne(n) + } + + #[inline] + fn put_i16(&mut self, n: i16) { + (**self).put_i16(n) + } + + #[inline] + fn put_i16_le(&mut self, n: i16) { + (**self).put_i16_le(n) + } + + #[inline] + fn put_i16_ne(&mut self, n: i16) { + (**self).put_i16_ne(n) + } + + #[inline] + fn put_u32(&mut self, n: u32) { + (**self).put_u32(n) + } + + #[inline] + fn put_u32_le(&mut self, n: u32) { + (**self).put_u32_le(n) + } + + #[inline] + fn put_u32_ne(&mut self, n: u32) { + (**self).put_u32_ne(n) + } + + #[inline] + fn put_i32(&mut self, n: i32) { + (**self).put_i32(n) + } + + #[inline] + fn put_i32_le(&mut self, n: i32) { + (**self).put_i32_le(n) + } + + #[inline] + fn put_i32_ne(&mut self, n: i32) { + (**self).put_i32_ne(n) + } + + #[inline] + fn put_u64(&mut self, n: u64) { + (**self).put_u64(n) + } + + #[inline] + fn put_u64_le(&mut self, n: u64) { + (**self).put_u64_le(n) + } + + #[inline] + fn put_u64_ne(&mut self, n: u64) { + (**self).put_u64_ne(n) + } + + #[inline] + fn put_i64(&mut self, n: i64) { + (**self).put_i64(n) + } + + #[inline] + fn put_i64_le(&mut self, n: i64) { + (**self).put_i64_le(n) + } + + #[inline] + 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::new(self) + } + + #[inline] + unsafe fn advance_mut(&mut self, cnt: usize) { + if self.len() < cnt { + panic_advance(&TryGetError { + requested: cnt, + available: self.len(), + }); + } + + // 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]) { + if self.len() < src.len() { + panic_advance(&TryGetError { + requested: src.len(), + available: self.len(), + }); + } + + self[..src.len()].copy_from_slice(src); + // SAFETY: We just initialized `src.len()` bytes. + unsafe { self.advance_mut(src.len()) }; + } + + #[inline] + fn put_bytes(&mut self, val: u8, cnt: usize) { + if self.len() < cnt { + panic_advance(&TryGetError { + requested: cnt, + available: self.len(), + }); + } + + // SAFETY: We just checked that the pointer is valid for `cnt` bytes. + unsafe { + ptr::write_bytes(self.as_mut_ptr(), val, cnt); + self.advance_mut(cnt); + } + } +} + +unsafe impl BufMut for &mut [core::mem::MaybeUninit] { + #[inline] + fn remaining_mut(&self) -> usize { + self.len() + } + + #[inline] + fn chunk_mut(&mut self) -> &mut UninitSlice { + UninitSlice::uninit(self) + } + + #[inline] + unsafe fn advance_mut(&mut self, cnt: usize) { + if self.len() < cnt { + panic_advance(&TryGetError { + requested: cnt, + available: self.len(), + }); + } + + // 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]) { + if self.len() < src.len() { + panic_advance(&TryGetError { + requested: src.len(), + available: self.len(), + }); + } + + // SAFETY: We just checked that the pointer is valid for `src.len()` bytes. + unsafe { + ptr::copy_nonoverlapping(src.as_ptr(), self.as_mut_ptr().cast(), src.len()); + self.advance_mut(src.len()); + } + } + + #[inline] + fn put_bytes(&mut self, val: u8, cnt: usize) { + if self.len() < cnt { + panic_advance(&TryGetError { + requested: cnt, + available: self.len(), + }); + } + + // SAFETY: We just checked that the pointer is valid for `cnt` bytes. + unsafe { + ptr::write_bytes(self.as_mut_ptr() as *mut u8, 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; + + if remaining < cnt { + panic_advance(&TryGetError { + requested: cnt, + available: remaining, + }); + } + + // Addition will not overflow since the sum is at most the capacity. + 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(); + // SAFETY: Since `ptr` is valid for `cap` bytes, `ptr.add(len)` must be + // valid for `cap - len` bytes. The subtraction will not underflow since + // `len <= cap`. + unsafe { UninitSlice::from_raw_parts_mut(ptr.add(len), cap - len) } + } + + // Specialize these methods so they can skip checking `remaining_mut` + // and `advance_mut`. + #[inline] + 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 s = src.chunk(); + let l = s.len(); + self.extend_from_slice(s); + src.advance(l); + } + } + + #[inline] + fn put_slice(&mut self, src: &[u8]) { + self.extend_from_slice(src); + } + + #[inline] + fn put_bytes(&mut self, val: u8, cnt: usize) { + // If the addition overflows, then the `resize` will fail. + let new_len = self.len().saturating_add(cnt); + 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/vendor/bytes/src/buf/chain.rs b/vendor/bytes/src/buf/chain.rs new file mode 100644 index 00000000..c8bc36de --- /dev/null +++ b/vendor/bytes/src/buf/chain.rs @@ -0,0 +1,240 @@ +use crate::buf::{IntoIter, UninitSlice}; +use crate::{Buf, BufMut}; + +#[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`]: Buf::chain +#[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().saturating_add(self.b.remaining()) + } + + 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) -> crate::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/vendor/bytes/src/buf/iter.rs b/vendor/bytes/src/buf/iter.rs new file mode 100644 index 00000000..74f9b991 --- /dev/null +++ b/vendor/bytes/src/buf/iter.rs @@ -0,0 +1,127 @@ +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); +/// ``` +#[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/vendor/bytes/src/buf/limit.rs b/vendor/bytes/src/buf/limit.rs new file mode 100644 index 00000000..b422be53 --- /dev/null +++ b/vendor/bytes/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/vendor/bytes/src/buf/mod.rs b/vendor/bytes/src/buf/mod.rs new file mode 100644 index 00000000..1bf0a47e --- /dev/null +++ b/vendor/bytes/src/buf/mod.rs @@ -0,0 +1,39 @@ +//! 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) + +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/vendor/bytes/src/buf/reader.rs b/vendor/bytes/src/buf/reader.rs new file mode 100644 index 00000000..52149495 --- /dev/null +++ b/vendor/bytes/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()`](Buf::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/vendor/bytes/src/buf/take.rs b/vendor/bytes/src/buf/take.rs new file mode 100644 index 00000000..acfeef6e --- /dev/null +++ b/vendor/bytes/src/buf/take.rs @@ -0,0 +1,204 @@ +use crate::Buf; + +use core::cmp; + +#[cfg(feature = "std")] +use std::io::IoSlice; + +/// 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()`](Buf::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) -> crate::Bytes { + assert!(len <= self.remaining(), "`len` greater than remaining"); + + let r = self.inner.copy_to_bytes(len); + self.limit -= len; + r + } + + #[cfg(feature = "std")] + fn chunks_vectored<'a>(&'a self, dst: &mut [IoSlice<'a>]) -> usize { + if self.limit == 0 { + return 0; + } + + const LEN: usize = 16; + let mut slices: [IoSlice<'a>; LEN] = [ + IoSlice::new(&[]), + IoSlice::new(&[]), + IoSlice::new(&[]), + IoSlice::new(&[]), + IoSlice::new(&[]), + IoSlice::new(&[]), + IoSlice::new(&[]), + IoSlice::new(&[]), + IoSlice::new(&[]), + IoSlice::new(&[]), + IoSlice::new(&[]), + IoSlice::new(&[]), + IoSlice::new(&[]), + IoSlice::new(&[]), + IoSlice::new(&[]), + IoSlice::new(&[]), + ]; + + let cnt = self + .inner + .chunks_vectored(&mut slices[..dst.len().min(LEN)]); + let mut limit = self.limit; + for (i, (dst, slice)) in dst[..cnt].iter_mut().zip(slices.iter()).enumerate() { + if let Some(buf) = slice.get(..limit) { + // SAFETY: We could do this safely with `IoSlice::advance` if we had a larger MSRV. + let buf = unsafe { std::mem::transmute::<&[u8], &'a [u8]>(buf) }; + *dst = IoSlice::new(buf); + return i + 1; + } else { + // SAFETY: We could do this safely with `IoSlice::advance` if we had a larger MSRV. + let buf = unsafe { std::mem::transmute::<&[u8], &'a [u8]>(slice) }; + *dst = IoSlice::new(buf); + limit -= slice.len(); + } + } + cnt + } +} diff --git a/vendor/bytes/src/buf/uninit_slice.rs b/vendor/bytes/src/buf/uninit_slice.rs new file mode 100644 index 00000000..aea096ae --- /dev/null +++ b/vendor/bytes/src/buf/uninit_slice.rs @@ -0,0 +1,257 @@ +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 { + /// Creates a `&mut UninitSlice` wrapping a slice of initialised memory. + /// + /// # Examples + /// + /// ``` + /// use bytes::buf::UninitSlice; + /// + /// let mut buffer = [0u8; 64]; + /// let slice = UninitSlice::new(&mut buffer[..]); + /// ``` + #[inline] + pub fn new(slice: &mut [u8]) -> &mut UninitSlice { + unsafe { &mut *(slice as *mut [u8] as *mut [MaybeUninit] as *mut UninitSlice) } + } + + /// Creates a `&mut UninitSlice` wrapping a slice of uninitialised memory. + /// + /// # Examples + /// + /// ``` + /// use bytes::buf::UninitSlice; + /// use core::mem::MaybeUninit; + /// + /// let mut buffer = [MaybeUninit::uninit(); 64]; + /// let slice = UninitSlice::uninit(&mut buffer[..]); + /// + /// let mut vec = Vec::with_capacity(1024); + /// let spare: &mut UninitSlice = vec.spare_capacity_mut().into(); + /// ``` + #[inline] + pub fn uninit(slice: &mut [MaybeUninit]) -> &mut UninitSlice { + unsafe { &mut *(slice as *mut [MaybeUninit] as *mut UninitSlice) } + } + + fn uninit_ref(slice: &[MaybeUninit]) -> &UninitSlice { + unsafe { &*(slice as *const [MaybeUninit] as *const 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::uninit(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 uninitialized + /// 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(&mut self) -> &mut [MaybeUninit] { + &mut self.0 + } + + /// 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() + } +} + +impl<'a> From<&'a mut [u8]> for &'a mut UninitSlice { + fn from(slice: &'a mut [u8]) -> Self { + UninitSlice::new(slice) + } +} + +impl<'a> From<&'a mut [MaybeUninit]> for &'a mut UninitSlice { + fn from(slice: &'a mut [MaybeUninit]) -> Self { + UninitSlice::uninit(slice) + } +} + +macro_rules! impl_index { + ($($t:ty),*) => { + $( + impl Index<$t> for UninitSlice { + type Output = UninitSlice; + + #[inline] + fn index(&self, index: $t) -> &UninitSlice { + UninitSlice::uninit_ref(&self.0[index]) + } + } + + impl IndexMut<$t> for UninitSlice { + #[inline] + fn index_mut(&mut self, index: $t) -> &mut UninitSlice { + UninitSlice::uninit(&mut self.0[index]) + } + } + )* + }; +} + +impl_index!( + Range, + RangeFrom, + RangeFull, + RangeInclusive, + RangeTo, + RangeToInclusive +); diff --git a/vendor/bytes/src/buf/vec_deque.rs b/vendor/bytes/src/buf/vec_deque.rs new file mode 100644 index 00000000..55d5636b --- /dev/null +++ b/vendor/bytes/src/buf/vec_deque.rs @@ -0,0 +1,40 @@ +use alloc::collections::VecDeque; +#[cfg(feature = "std")] +use std::io; + +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 + } + } + + #[cfg(feature = "std")] + fn chunks_vectored<'a>(&'a self, dst: &mut [io::IoSlice<'a>]) -> usize { + if self.is_empty() || dst.is_empty() { + return 0; + } + + let (s1, s2) = self.as_slices(); + dst[0] = io::IoSlice::new(s1); + if s2.is_empty() || dst.len() == 1 { + return 1; + } + + dst[1] = io::IoSlice::new(s2); + 2 + } + + fn advance(&mut self, cnt: usize) { + self.drain(..cnt); + } +} diff --git a/vendor/bytes/src/buf/writer.rs b/vendor/bytes/src/buf/writer.rs new file mode 100644 index 00000000..e72348f4 --- /dev/null +++ b/vendor/bytes/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()`](BufMut::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_slice(&src[..n]); + Ok(n) + } + + fn flush(&mut self) -> io::Result<()> { + Ok(()) + } +} diff --git a/vendor/bytes/src/bytes.rs b/vendor/bytes/src/bytes.rs new file mode 100644 index 00000000..cdb6ea55 --- /dev/null +++ b/vendor/bytes/src/bytes.rs @@ -0,0 +1,1680 @@ +use core::iter::FromIterator; +use core::mem::{self, ManuallyDrop}; +use core::ops::{Deref, RangeBounds}; +use core::ptr::NonNull; +use core::{cmp, fmt, hash, 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::{offset_from, Buf, BytesMut}; + +/// 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 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, + pub to_mut: unsafe fn(&AtomicPtr<()>, *const u8, usize) -> BytesMut, + /// fn(data) + pub is_unique: unsafe fn(&AtomicPtr<()>) -> bool, + /// 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) + } + + /// Creates a new empty `Bytes`. + #[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, + } + } + + /// Creates a new `Bytes` from a static slice. + #[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, + } + } + + /// Creates a new `Bytes` with length zero and the given pointer as the address. + fn new_empty_with_ptr(ptr: *const u8) -> Self { + debug_assert!(!ptr.is_null()); + + // Detach this pointer's provenance from whichever allocation it came from, and reattach it + // to the provenance of the fake ZST [u8;0] at the same address. + let ptr = without_provenance(ptr as usize); + + Bytes { + ptr, + len: 0, + data: AtomicPtr::new(ptr::null_mut()), + vtable: &STATIC_VTABLE, + } + } + + /// Create [Bytes] with a buffer whose lifetime is controlled + /// via an explicit owner. + /// + /// A common use case is to zero-copy construct from mapped memory. + /// + /// ``` + /// # struct File; + /// # + /// # impl File { + /// # pub fn open(_: &str) -> Result { + /// # Ok(Self) + /// # } + /// # } + /// # + /// # mod memmap2 { + /// # pub struct Mmap; + /// # + /// # impl Mmap { + /// # pub unsafe fn map(_file: &super::File) -> Result { + /// # Ok(Self) + /// # } + /// # } + /// # + /// # impl AsRef<[u8]> for Mmap { + /// # fn as_ref(&self) -> &[u8] { + /// # b"buf" + /// # } + /// # } + /// # } + /// use bytes::Bytes; + /// use memmap2::Mmap; + /// + /// # fn main() -> Result<(), ()> { + /// let file = File::open("upload_bundle.tar.gz")?; + /// let mmap = unsafe { Mmap::map(&file) }?; + /// let b = Bytes::from_owner(mmap); + /// # Ok(()) + /// # } + /// ``` + /// + /// The `owner` will be transferred to the constructed [Bytes] object, which + /// will ensure it is dropped once all remaining clones of the constructed + /// object are dropped. The owner will then be responsible for dropping the + /// specified region of memory as part of its [Drop] implementation. + /// + /// Note that converting [Bytes] constructed from an owner into a [BytesMut] + /// will always create a deep copy of the buffer into newly allocated memory. + pub fn from_owner(owner: T) -> Self + where + T: AsRef<[u8]> + Send + 'static, + { + // Safety & Miri: + // The ownership of `owner` is first transferred to the `Owned` wrapper and `Bytes` object. + // This ensures that the owner is pinned in memory, allowing us to call `.as_ref()` safely + // since the lifetime of the owner is controlled by the lifetime of the new `Bytes` object, + // and the lifetime of the resulting borrowed `&[u8]` matches that of the owner. + // Note that this remains safe so long as we only call `.as_ref()` once. + // + // There are some additional special considerations here: + // * We rely on Bytes's Drop impl to clean up memory should `.as_ref()` panic. + // * Setting the `ptr` and `len` on the bytes object last (after moving the owner to + // Bytes) allows Miri checks to pass since it avoids obtaining the `&[u8]` slice + // from a stack-owned Box. + // More details on this: https://github.com/tokio-rs/bytes/pull/742/#discussion_r1813375863 + // and: https://github.com/tokio-rs/bytes/pull/742/#discussion_r1813316032 + + let owned = Box::into_raw(Box::new(Owned { + lifetime: OwnedLifetime { + ref_cnt: AtomicUsize::new(1), + drop: owned_box_and_drop::, + }, + owner, + })); + + let mut ret = Bytes { + ptr: NonNull::dangling().as_ptr(), + len: 0, + data: AtomicPtr::new(owned.cast()), + vtable: &OWNED_VTABLE, + }; + + let buf = unsafe { &*owned }.owner.as_ref(); + ret.ptr = buf.as_ptr(); + ret.len = buf.len(); + + ret + } + + /// 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 + } + + /// Returns true if this is the only reference to the data and + /// `Into` would avoid cloning the underlying buffer. + /// + /// Always returns false if the data is backed by a [static slice](Bytes::from_static), + /// or an [owner](Bytes::from_owner). + /// + /// The result of this method may be invalidated immediately if another + /// thread clones this value while this is being called. Ensure you have + /// unique access to this value (`&mut Bytes`) first if you need to be + /// certain the result is valid (i.e. for safety reasons). + /// # Examples + /// + /// ``` + /// use bytes::Bytes; + /// + /// let a = Bytes::from(vec![1, 2, 3]); + /// assert!(a.is_unique()); + /// let b = a.clone(); + /// assert!(!a.is_unique()); + /// ``` + pub fn is_unique(&self) -> bool { + unsafe { (self.vtable.is_unique)(&self.data) } + } + + /// 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.checked_add(1).expect("out of range"), + 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)`. It's guaranteed that the memory does not + /// move, that is, the address of `self` does not change, and the address of + /// the returned slice is `at` bytes after that. + /// + /// 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 { + if at == self.len() { + return Bytes::new_empty_with_ptr(self.ptr.wrapping_add(at)); + } + + if at == 0 { + return mem::replace(self, Bytes::new_empty_with_ptr(self.ptr)); + } + + assert!( + at <= self.len(), + "split_off out of bounds: {:?} <= {:?}", + at, + self.len(), + ); + + 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 { + if at == self.len() { + let end_ptr = self.ptr.wrapping_add(at); + return mem::replace(self, Bytes::new_empty_with_ptr(end_ptr)); + } + + if at == 0 { + return Bytes::new_empty_with_ptr(self.ptr); + } + + assert!( + at <= self.len(), + "split_to out of bounds: {:?} <= {:?}", + at, + self.len(), + ); + + 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](`Self::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"[..]); + /// ``` + #[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); + } + + /// Try to convert self into `BytesMut`. + /// + /// If `self` is unique for the entire original buffer, this will succeed + /// and return a `BytesMut` with the contents of `self` without copying. + /// If `self` is not unique for the entire original buffer, this will fail + /// and return self. + /// + /// This will also always fail if the buffer was constructed via either + /// [from_owner](Bytes::from_owner) or [from_static](Bytes::from_static). + /// + /// # Examples + /// + /// ``` + /// use bytes::{Bytes, BytesMut}; + /// + /// let bytes = Bytes::from(b"hello".to_vec()); + /// assert_eq!(bytes.try_into_mut(), Ok(BytesMut::from(&b"hello"[..]))); + /// ``` + pub fn try_into_mut(self) -> Result { + if self.is_unique() { + Ok(self.into()) + } else { + Err(self) + } + } + + #[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) -> Self { + self.split_to(len) + } +} + +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 = ManuallyDrop::new(vec); + let ptr = vec.as_mut_ptr(); + let len = vec.len(); + let cap = vec.capacity(); + + // Avoid an extra allocation if possible. + if len == cap { + let vec = ManuallyDrop::into_inner(vec); + return Bytes::from(vec.into_boxed_slice()); + } + + let shared = Box::new(Shared { + buf: ptr, + cap, + ref_cnt: AtomicUsize::new(1), + }); + + 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 BytesMut { + /// Convert self into `BytesMut`. + /// + /// If `bytes` is unique for the entire original buffer, this will return a + /// `BytesMut` with the contents of `bytes` without copying. + /// If `bytes` is not unique for the entire original buffer, this will make + /// a copy of `bytes` subset of the original buffer in a new `BytesMut`. + /// + /// # Examples + /// + /// ``` + /// use bytes::{Bytes, BytesMut}; + /// + /// let bytes = Bytes::from(b"hello".to_vec()); + /// assert_eq!(BytesMut::from(bytes), BytesMut::from(&b"hello"[..])); + /// ``` + fn from(bytes: Bytes) -> Self { + let bytes = ManuallyDrop::new(bytes); + unsafe { (bytes.vtable.to_mut)(&bytes.data, bytes.ptr, bytes.len) } + } +} + +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 = 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, + to_mut: static_to_mut, + is_unique: static_is_unique, + 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_to_mut(_: &AtomicPtr<()>, ptr: *const u8, len: usize) -> BytesMut { + let slice = slice::from_raw_parts(ptr, len); + BytesMut::from(slice) +} + +fn static_is_unique(_: &AtomicPtr<()>) -> bool { + false +} + +unsafe fn static_drop(_: &mut AtomicPtr<()>, _: *const u8, _: usize) { + // nothing to drop for &'static [u8] +} + +// ===== impl OwnedVtable ===== + +#[repr(C)] +struct OwnedLifetime { + ref_cnt: AtomicUsize, + drop: unsafe fn(*mut ()), +} + +#[repr(C)] +struct Owned { + lifetime: OwnedLifetime, + owner: T, +} + +unsafe fn owned_box_and_drop(ptr: *mut ()) { + let b: Box> = Box::from_raw(ptr as _); + drop(b); +} + +unsafe fn owned_clone(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Bytes { + let owned = data.load(Ordering::Relaxed); + let ref_cnt = &(*owned.cast::()).ref_cnt; + let old_cnt = ref_cnt.fetch_add(1, Ordering::Relaxed); + if old_cnt > usize::MAX >> 1 { + crate::abort() + } + + Bytes { + ptr, + len, + data: AtomicPtr::new(owned as _), + vtable: &OWNED_VTABLE, + } +} + +unsafe fn owned_to_vec(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Vec { + let slice = slice::from_raw_parts(ptr, len); + let vec = slice.to_vec(); + owned_drop_impl(data.load(Ordering::Relaxed)); + vec +} + +unsafe fn owned_to_mut(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> BytesMut { + BytesMut::from_vec(owned_to_vec(data, ptr, len)) +} + +unsafe fn owned_is_unique(_data: &AtomicPtr<()>) -> bool { + false +} + +unsafe fn owned_drop_impl(owned: *mut ()) { + let lifetime = owned.cast::(); + let ref_cnt = &(*lifetime).ref_cnt; + + let old_cnt = ref_cnt.fetch_sub(1, Ordering::Release); + debug_assert!( + old_cnt > 0 && old_cnt <= usize::MAX >> 1, + "expected non-zero refcount and no underflow" + ); + if old_cnt != 1 { + return; + } + ref_cnt.load(Ordering::Acquire); + + let drop_fn = &(*lifetime).drop; + drop_fn(owned) +} + +unsafe fn owned_drop(data: &mut AtomicPtr<()>, _ptr: *const u8, _len: usize) { + let owned = data.load(Ordering::Relaxed); + owned_drop_impl(owned); +} + +static OWNED_VTABLE: Vtable = Vtable { + clone: owned_clone, + to_vec: owned_to_vec, + to_mut: owned_to_mut, + is_unique: owned_is_unique, + drop: owned_drop, +}; + +// ===== impl PromotableVtable ===== + +static PROMOTABLE_EVEN_VTABLE: Vtable = Vtable { + clone: promotable_even_clone, + to_vec: promotable_even_to_vec, + to_mut: promotable_even_to_mut, + is_unique: promotable_is_unique, + drop: promotable_even_drop, +}; + +static PROMOTABLE_ODD_VTABLE: Vtable = Vtable { + clone: promotable_odd_clone, + to_vec: promotable_odd_to_vec, + to_mut: promotable_odd_to_mut, + is_unique: promotable_is_unique, + 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 = offset_from(ptr, buf) + len; + + // Copy back buffer + ptr::copy(ptr, buf, len); + + Vec::from_raw_parts(buf, len, cap) + } +} + +unsafe fn promotable_to_mut( + data: &AtomicPtr<()>, + ptr: *const u8, + len: usize, + f: fn(*mut ()) -> *mut u8, +) -> BytesMut { + let shared = data.load(Ordering::Acquire); + let kind = shared as usize & KIND_MASK; + + if kind == KIND_ARC { + shared_to_mut_impl(shared.cast(), ptr, len) + } else { + // KIND_VEC is a view of an underlying buffer at a certain offset. + // The ptr + len always represents the end of that buffer. + // Before truncating it, it is first promoted to KIND_ARC. + // Thus, we can safely reconstruct a Vec from it without leaking memory. + debug_assert_eq!(kind, KIND_VEC); + + let buf = f(shared); + let off = offset_from(ptr, buf); + let cap = off + len; + let v = Vec::from_raw_parts(buf, cap, cap); + + let mut b = BytesMut::from_vec(v); + b.advance_unchecked(off); + b + } +} + +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_to_mut(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> BytesMut { + promotable_to_mut(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_to_mut(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> BytesMut { + promotable_to_mut(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 promotable_is_unique(data: &AtomicPtr<()>) -> bool { + let shared = data.load(Ordering::Acquire); + let kind = shared as usize & KIND_MASK; + + if kind == KIND_ARC { + let ref_cnt = (*shared.cast::()).ref_cnt.load(Ordering::Relaxed); + ref_cnt == 1 + } else { + true + } +} + +unsafe fn free_boxed_slice(buf: *mut u8, offset: *const u8, len: usize) { + let cap = offset_from(offset, buf) + 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, + to_mut: shared_to_mut, + is_unique: shared_is_unique, + 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() + { + // Deallocate the `Shared` instance without running its destructor. + let shared = *Box::from_raw(shared); + let shared = ManuallyDrop::new(shared); + let buf = shared.buf; + let cap = shared.cap; + + // 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_to_mut_impl(shared: *mut Shared, ptr: *const u8, len: usize) -> BytesMut { + // 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_cnt` 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_cnt` is decremented. As such, + // this `Acquire` will guarantee that those mutations are + // visible to the current thread. + // + // Otherwise, we take the other branch, copy the data and call `release_shared`. + if (*shared).ref_cnt.load(Ordering::Acquire) == 1 { + // Deallocate the `Shared` instance without running its destructor. + let shared = *Box::from_raw(shared); + let shared = ManuallyDrop::new(shared); + let buf = shared.buf; + let cap = shared.cap; + + // Rebuild Vec + let off = offset_from(ptr, buf); + let v = Vec::from_raw_parts(buf, len + off, cap); + + let mut b = BytesMut::from_vec(v); + b.advance_unchecked(off); + b + } else { + // Copy the data from Shared in a new Vec, then release it + let v = slice::from_raw_parts(ptr, len).to_vec(); + release_shared(shared); + BytesMut::from_vec(v) + } +} + +unsafe fn shared_to_mut(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> BytesMut { + shared_to_mut_impl(data.load(Ordering::Relaxed).cast(), ptr, len) +} + +pub(crate) unsafe fn shared_is_unique(data: &AtomicPtr<()>) -> bool { + let shared = data.load(Ordering::Acquire); + let ref_cnt = (*shared.cast::()).ref_cnt.load(Ordering::Relaxed); + ref_cnt == 1 +} + +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_from(offset, buf) + 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 +} + +fn without_provenance(ptr: usize) -> *const u8 { + core::ptr::null::().wrapping_add(ptr) +} + +// 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/vendor/bytes/src/bytes_mut.rs b/vendor/bytes/src/bytes_mut.rs new file mode 100644 index 00000000..d5db5124 --- /dev/null +++ b/vendor/bytes/src/bytes_mut.rs @@ -0,0 +1,1921 @@ +use core::iter::FromIterator; +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::{offset_from, Buf, BufMut, Bytes, TryGetError}; + +/// 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, +} + +// 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. + +// 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; + +const VEC_POS_OFFSET: usize = 5; +// 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 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(self) -> Bytes { + let bytes = ManuallyDrop::new(self); + if bytes.kind() == KIND_VEC { + // Just re-use `Bytes` internal Vec vtable + unsafe { + let off = bytes.get_vec_pos(); + let vec = rebuild_vec(bytes.ptr.as_ptr(), bytes.len, bytes.cap, off); + let mut b: Bytes = vec.into(); + b.advance(off); + b + } + } else { + debug_assert_eq!(bytes.kind(), KIND_ARC); + + let ptr = bytes.ptr.as_ptr(); + let len = bytes.len; + let data = AtomicPtr::new(bytes.data.cast()); + unsafe { Bytes::with_vtable(ptr, len, data, &SHARED_VTABLE) } + } + } + + /// Creates a new `BytesMut` containing `len` zeros. + /// + /// The resulting object has a length of `len` and a capacity greater + /// than or equal to `len`. The entire length of the object will be filled + /// with zeros. + /// + /// On some platforms or allocators this function may be faster than + /// a manual implementation. + /// + /// # Examples + /// + /// ``` + /// use bytes::BytesMut; + /// + /// let zeros = BytesMut::zeroed(42); + /// + /// assert!(zeros.capacity() >= 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)`. It's guaranteed that the + /// memory does not move, that is, the address of `self` does not change, + /// and the address of the returned slice is `at` bytes after that. + /// + /// 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(); + // SAFETY: We've checked that `at` <= `self.capacity()` above. + other.advance_unchecked(at); + self.cap = at; + self.len = cmp::min(self.len, 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::clear 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(); + // SAFETY: We've checked that `at` <= `self.len()` and we know that `self.len()` <= + // `self.capacity()`. + self.advance_unchecked(at); + other.cap = at; + other.len = 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](`Self::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"[..]); + /// ``` + pub fn truncate(&mut self, len: usize) { + if len <= self.len() { + // SAFETY: Shrinking the buffer cannot expose uninitialized bytes. + 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) { + // SAFETY: Setting the length to zero cannot expose uninitialized bytes. + unsafe { self.set_len(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 additional = if let Some(additional) = new_len.checked_sub(self.len()) { + additional + } else { + self.truncate(new_len); + return; + }; + + if additional == 0 { + return; + } + + self.reserve(additional); + let dst = self.spare_capacity_mut().as_mut_ptr(); + // SAFETY: `spare_capacity_mut` returns a valid, properly aligned pointer and we've + // reserved enough space to write `additional` bytes. + unsafe { ptr::write_bytes(dst, value, additional) }; + + // SAFETY: There are at least `new_len` initialized bytes in the buffer so no + // uninitialized bytes are being exposed. + unsafe { self.set_len(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; + } + + // will always succeed + let _ = self.reserve_inner(additional, true); + } + + // In separate function to allow the short-circuits in `reserve` and `try_reclaim` to + // be inline-able. Significantly helps performance. Returns false if it did not succeed. + fn reserve_inner(&mut self, additional: usize, allocate: bool) -> bool { + 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 = 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().sub(off); + // 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); + + // Length stays constant, but since we moved backwards we + // can gain capacity back. + self.cap += off; + } else { + if !allocate { + return false; + } + // 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.cap = v.capacity() - off; + debug_assert_eq!(self.len, v.len() - off); + } + + return true; + } + } + + 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 = match len.checked_add(additional) { + Some(new_cap) => new_cap, + None if !allocate => return false, + None => panic!("overflow"), + }; + + unsafe { + // 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 { + if !allocate { + return false; + } + // 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 true; + } + } + if !allocate { + return false; + } + + let original_capacity_repr = unsafe { (*shared).original_capacity_repr }; + let original_capacity = original_capacity_from_repr(original_capacity_repr); + + 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.cap = v.capacity(); + debug_assert_eq!(self.len, v.len()); + return true; + } + + /// Attempts to cheaply reclaim already allocated capacity for at least `additional` more + /// bytes to be inserted into the given `BytesMut` and returns `true` if it succeeded. + /// + /// `try_reclaim` behaves exactly like `reserve`, except that it never allocates new storage + /// and returns a `bool` indicating whether it was successful in doing so: + /// + /// `try_reclaim` returns false under these conditions: + /// - The spare capacity left is less than `additional` bytes AND + /// - The existing allocation cannot be reclaimed cheaply or it was less than + /// `additional` bytes in size + /// + /// Reclaiming the allocation cheaply is possible if the `BytesMut` has no outstanding + /// references through other `BytesMut`s or `Bytes` which point to the same underlying + /// storage. + /// + /// # Examples + /// + /// ``` + /// use bytes::BytesMut; + /// + /// let mut buf = BytesMut::with_capacity(64); + /// assert_eq!(true, buf.try_reclaim(64)); + /// assert_eq!(64, buf.capacity()); + /// + /// buf.extend_from_slice(b"abcd"); + /// let mut split = buf.split(); + /// assert_eq!(60, buf.capacity()); + /// assert_eq!(4, split.capacity()); + /// assert_eq!(false, split.try_reclaim(64)); + /// assert_eq!(false, buf.try_reclaim(64)); + /// // The split buffer is filled with "abcd" + /// assert_eq!(false, split.try_reclaim(4)); + /// // buf is empty and has capacity for 60 bytes + /// assert_eq!(true, buf.try_reclaim(60)); + /// + /// drop(buf); + /// assert_eq!(false, split.try_reclaim(64)); + /// + /// split.clear(); + /// assert_eq!(4, split.capacity()); + /// assert_eq!(true, split.try_reclaim(64)); + /// assert_eq!(64, split.capacity()); + /// ``` + // I tried splitting out try_reclaim_inner after the short circuits, but it was inlined + // regardless with Rust 1.78.0 so probably not worth it + #[inline] + #[must_use = "consider BytesMut::reserve if you need an infallible reservation"] + pub fn try_reclaim(&mut self, additional: usize) -> bool { + 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 true; + } + + self.reserve_inner(additional, false) + } + + /// 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[..]); + /// ``` + #[inline] + 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(vec: Vec) -> BytesMut { + let mut vec = ManuallyDrop::new(vec); + let ptr = vptr(vec.as_mut_ptr()); + let len = vec.len(); + let cap = vec.capacity(); + + 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) } + } + + /// Advance the buffer without bounds checking. + /// + /// # SAFETY + /// + /// The caller must ensure that `count` <= `self.cap`. + pub(crate) unsafe fn advance_unchecked(&mut self, count: usize) { + // Setting the start to 0 is a no-op, so return early if this is the + // case. + if count == 0 { + return; + } + + debug_assert!(count <= 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 pos = self.get_vec_pos() + count; + + if pos <= MAX_VEC_POS { + self.set_vec_pos(pos); + } 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(count)); + self.len = self.len.checked_sub(count).unwrap_or(0); + self.cap -= count; + } + + 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(&self) -> usize { + debug_assert_eq!(self.kind(), KIND_VEC); + + self.data as usize >> VEC_POS_OFFSET + } + + #[inline] + unsafe fn set_vec_pos(&mut self, pos: usize) { + debug_assert_eq!(self.kind(), KIND_VEC); + debug_assert!(pos <= MAX_VEC_POS); + + self.data = invalid_ptr((pos << VEC_POS_OFFSET) | (self.data as usize & 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 { + // SAFETY: We've checked that `cnt` <= `self.remaining()` and we know that + // `self.remaining()` <= `self.cap`. + self.advance_unchecked(cnt); + } + } + + fn copy_to_bytes(&mut self, len: usize) -> 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 remaining = self.cap - self.len(); + if cnt > remaining { + super::panic_advance(&TryGetError { + requested: cnt, + available: remaining, + }); + } + // Addition won't overflow since it is at most `self.cap`. + self.len = self.len() + cnt; + } + + #[inline] + fn chunk_mut(&mut self) -> &mut UninitSlice { + if self.capacity() == self.len() { + self.reserve(64); + } + self.spare_capacity_mut().into() + } + + // 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 + for b in iter { + 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)) +} + +#[cfg(test)] +mod tests { + use super::*; + + #[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(bytes: BytesMut) -> Self { + let kind = bytes.kind(); + let bytes = ManuallyDrop::new(bytes); + + 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 { + 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 ManuallyDrop::into_inner(bytes).deref().to_vec(); + } + }; + + let len = bytes.len; + + unsafe { + ptr::copy(bytes.ptr.as_ptr(), vec.as_mut_ptr(), len); + vec.set_len(len); + } + + 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::() +} + +unsafe fn rebuild_vec(ptr: *mut u8, mut len: usize, mut cap: usize, off: usize) -> Vec { + let ptr = ptr.sub(off); + 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, + to_mut: shared_v_to_mut, + is_unique: shared_v_is_unique, + 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_to_mut(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> BytesMut { + let shared: *mut Shared = data.load(Ordering::Relaxed).cast(); + + if (*shared).is_unique() { + let shared = &mut *shared; + + // The capacity is always the original capacity of the buffer + // minus the offset from the start of the buffer + let v = &mut shared.vec; + let v_capacity = v.capacity(); + let v_ptr = v.as_mut_ptr(); + let offset = offset_from(ptr as *mut u8, v_ptr); + let cap = v_capacity - offset; + + let ptr = vptr(ptr as *mut u8); + + BytesMut { + ptr, + len, + cap, + data: shared, + } + } else { + let v = slice::from_raw_parts(ptr, len).to_vec(); + release_shared(shared); + BytesMut::from_vec(v) + } +} + +unsafe fn shared_v_is_unique(data: &AtomicPtr<()>) -> bool { + let shared = data.load(Ordering::Acquire); + let ref_count = (*shared.cast::()).ref_count.load(Ordering::Relaxed); + ref_count == 1 +} + +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/vendor/bytes/src/fmt/debug.rs b/vendor/bytes/src/fmt/debug.rs new file mode 100644 index 00000000..82d0aa5e --- /dev/null +++ b/vendor/bytes/src/fmt/debug.rs @@ -0,0 +1,40 @@ +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(()) + } +} + +fmt_impl!(Debug, Bytes); +fmt_impl!(Debug, BytesMut); diff --git a/vendor/bytes/src/fmt/hex.rs b/vendor/bytes/src/fmt/hex.rs new file mode 100644 index 00000000..1203b419 --- /dev/null +++ b/vendor/bytes/src/fmt/hex.rs @@ -0,0 +1,27 @@ +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(()) + } +} + +fmt_impl!(LowerHex, Bytes); +fmt_impl!(LowerHex, BytesMut); +fmt_impl!(UpperHex, Bytes); +fmt_impl!(UpperHex, BytesMut); diff --git a/vendor/bytes/src/fmt/mod.rs b/vendor/bytes/src/fmt/mod.rs new file mode 100644 index 00000000..b8a0eafa --- /dev/null +++ b/vendor/bytes/src/fmt/mod.rs @@ -0,0 +1,15 @@ +macro_rules! fmt_impl { + ($tr:ident, $ty:ty) => { + impl $tr for $ty { + fn fmt(&self, f: &mut Formatter<'_>) -> Result { + $tr::fmt(&BytesRef(self.as_ref()), f) + } + } + }; +} + +mod debug; +mod hex; + +/// `BytesRef` is not a part of public API of bytes crate. +struct BytesRef<'a>(&'a [u8]); diff --git a/vendor/bytes/src/lib.rs b/vendor/bytes/src/lib.rs new file mode 100644 index 00000000..08c42494 --- /dev/null +++ b/vendor/bytes/src/lib.rs @@ -0,0 +1,199 @@ +#![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`]) and traits for working with buffer +//! implementations ([`Buf`], [`BufMut`]). +//! +//! # `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](`Bytes`) for more details. +//! +//! # `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"); + } +} + +#[inline(always)] +#[cfg(feature = "std")] +fn saturating_sub_usize_u64(a: usize, b: u64) -> usize { + use core::convert::TryFrom; + match usize::try_from(b) { + Ok(b) => a.saturating_sub(b), + Err(_) => 0, + } +} + +#[inline(always)] +#[cfg(feature = "std")] +fn min_u64_usize(a: u64, b: usize) -> usize { + use core::convert::TryFrom; + match usize::try_from(a) { + Ok(a) => usize::min(a, b), + Err(_) => b, + } +} + +/// Error type for the `try_get_` methods of [`Buf`]. +/// Indicates that there were not enough remaining +/// bytes in the buffer while attempting +/// to get a value from a [`Buf`] with one +/// of the `try_get_` methods. +#[derive(Debug, PartialEq, Eq)] +pub struct TryGetError { + /// The number of bytes necessary to get the value + pub requested: usize, + + /// The number of bytes available in the buffer + pub available: usize, +} + +impl core::fmt::Display for TryGetError { + fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> Result<(), core::fmt::Error> { + write!( + f, + "Not enough bytes remaining in buffer to read value (requested {} but only {} available)", + self.requested, + self.available + ) + } +} + +#[cfg(feature = "std")] +impl std::error::Error for TryGetError {} + +#[cfg(feature = "std")] +impl From for std::io::Error { + fn from(error: TryGetError) -> Self { + std::io::Error::new(std::io::ErrorKind::Other, error) + } +} + +/// Panic with a nice error message. +#[cold] +fn panic_advance(error_info: &TryGetError) -> ! { + panic!( + "advance out of bounds: the len is {} but advancing by {}", + error_info.available, error_info.requested + ); +} + +#[cold] +fn panic_does_not_fit(size: usize, nbytes: usize) -> ! { + panic!( + "size too large: the integer type can fit {} bytes, but nbytes is {}", + size, nbytes + ); +} + +/// 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 stabilized +/// in 1.47, we cannot use it. +#[inline] +fn offset_from(dst: *const u8, original: *const u8) -> usize { + dst as usize - original as usize +} diff --git a/vendor/bytes/src/loom.rs b/vendor/bytes/src/loom.rs new file mode 100644 index 00000000..c8092909 --- /dev/null +++ b/vendor/bytes/src/loom.rs @@ -0,0 +1,33 @@ +#[cfg(not(all(test, loom)))] +pub(crate) mod sync { + pub(crate) mod atomic { + #[cfg(not(feature = "extra-platforms"))] + pub(crate) use core::sync::atomic::{AtomicPtr, AtomicUsize, Ordering}; + #[cfg(feature = "extra-platforms")] + pub(crate) use extra_platforms::{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/vendor/bytes/src/serde.rs b/vendor/bytes/src/serde.rs new file mode 100644 index 00000000..0a5bd144 --- /dev/null +++ b/vendor/bytes/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); -- cgit v1.2.3