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-rw-r--r--third_party/rust/bytes/src/buf/buf_impl.rs1394
-rw-r--r--third_party/rust/bytes/src/buf/buf_mut.rs1493
-rw-r--r--third_party/rust/bytes/src/buf/chain.rs242
-rw-r--r--third_party/rust/bytes/src/buf/iter.rs130
-rw-r--r--third_party/rust/bytes/src/buf/limit.rs75
-rw-r--r--third_party/rust/bytes/src/buf/mod.rs41
-rw-r--r--third_party/rust/bytes/src/buf/reader.rs81
-rw-r--r--third_party/rust/bytes/src/buf/take.rs155
-rw-r--r--third_party/rust/bytes/src/buf/uninit_slice.rs213
-rw-r--r--third_party/rust/bytes/src/buf/vec_deque.rs22
-rw-r--r--third_party/rust/bytes/src/buf/writer.rs88
-rw-r--r--third_party/rust/bytes/src/bytes.rs1304
-rw-r--r--third_party/rust/bytes/src/bytes_mut.rs1812
-rw-r--r--third_party/rust/bytes/src/fmt/debug.rs49
-rw-r--r--third_party/rust/bytes/src/fmt/hex.rs37
-rw-r--r--third_party/rust/bytes/src/fmt/mod.rs5
-rw-r--r--third_party/rust/bytes/src/lib.rs117
-rw-r--r--third_party/rust/bytes/src/loom.rs30
-rw-r--r--third_party/rust/bytes/src/serde.rs89
19 files changed, 7377 insertions, 0 deletions
diff --git a/third_party/rust/bytes/src/buf/buf_impl.rs b/third_party/rust/bytes/src/buf/buf_impl.rs
new file mode 100644
index 0000000000..366cfc9898
--- /dev/null
+++ b/third_party/rust/bytes/src/buf/buf_impl.rs
@@ -0,0 +1,1394 @@
+#[cfg(feature = "std")]
+use crate::buf::{reader, Reader};
+use crate::buf::{take, Chain, Take};
+
+use core::{cmp, mem, ptr};
+
+#[cfg(feature = "std")]
+use std::io::IoSlice;
+
+use alloc::boxed::Box;
+
+macro_rules! buf_get_impl {
+ ($this:ident, $typ:tt::$conv:tt) => {{
+ const SIZE: usize = mem::size_of::<$typ>();
+ // try to convert directly from the bytes
+ // this Option<ret> trick is to avoid keeping a borrow on self
+ // when advance() is called (mut borrow) and to call bytes() only once
+ let ret = $this
+ .chunk()
+ .get(..SIZE)
+ .map(|src| unsafe { $typ::$conv(*(src as *const _ as *const [_; SIZE])) });
+
+ if let Some(ret) = ret {
+ // if the direct conversion was possible, advance and return
+ $this.advance(SIZE);
+ return ret;
+ } else {
+ // if not we copy the bytes in a temp buffer then convert
+ let mut buf = [0; SIZE];
+ $this.copy_to_slice(&mut buf); // (do the advance)
+ return $typ::$conv(buf);
+ }
+ }};
+ (le => $this:ident, $typ:tt, $len_to_read:expr) => {{
+ debug_assert!(mem::size_of::<$typ>() >= $len_to_read);
+
+ // The same trick as above does not improve the best case speed.
+ // It seems to be linked to the way the method is optimised by the compiler
+ let mut buf = [0; (mem::size_of::<$typ>())];
+ $this.copy_to_slice(&mut buf[..($len_to_read)]);
+ return $typ::from_le_bytes(buf);
+ }};
+ (be => $this:ident, $typ:tt, $len_to_read:expr) => {{
+ debug_assert!(mem::size_of::<$typ>() >= $len_to_read);
+
+ let mut buf = [0; (mem::size_of::<$typ>())];
+ $this.copy_to_slice(&mut buf[mem::size_of::<$typ>() - ($len_to_read)..]);
+ return $typ::from_be_bytes(buf);
+ }};
+}
+
+/// Read bytes from a buffer.
+///
+/// A buffer stores bytes in memory such that read operations are infallible.
+/// The underlying storage may or may not be in contiguous memory. A `Buf` value
+/// is a cursor into the buffer. Reading from `Buf` advances the cursor
+/// position. It can be thought of as an efficient `Iterator` for collections of
+/// bytes.
+///
+/// The simplest `Buf` is a `&[u8]`.
+///
+/// ```
+/// use bytes::Buf;
+///
+/// let mut buf = &b"hello world"[..];
+///
+/// assert_eq!(b'h', buf.get_u8());
+/// assert_eq!(b'e', buf.get_u8());
+/// assert_eq!(b'l', buf.get_u8());
+///
+/// let mut rest = [0; 8];
+/// buf.copy_to_slice(&mut rest);
+///
+/// assert_eq!(&rest[..], &b"lo world"[..]);
+/// ```
+pub trait Buf {
+ /// Returns the number of bytes between the current position and the end of
+ /// the buffer.
+ ///
+ /// This value is greater than or equal to the length of the slice returned
+ /// by `chunk()`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"hello world"[..];
+ ///
+ /// assert_eq!(buf.remaining(), 11);
+ ///
+ /// buf.get_u8();
+ ///
+ /// assert_eq!(buf.remaining(), 10);
+ /// ```
+ ///
+ /// # Implementer notes
+ ///
+ /// Implementations of `remaining` should ensure that the return value does
+ /// not change unless a call is made to `advance` or any other function that
+ /// is documented to change the `Buf`'s current position.
+ fn remaining(&self) -> usize;
+
+ /// Returns a slice starting at the current position and of length between 0
+ /// and `Buf::remaining()`. Note that this *can* return shorter slice (this allows
+ /// non-continuous internal representation).
+ ///
+ /// This is a lower level function. Most operations are done with other
+ /// functions.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"hello world"[..];
+ ///
+ /// assert_eq!(buf.chunk(), &b"hello world"[..]);
+ ///
+ /// buf.advance(6);
+ ///
+ /// assert_eq!(buf.chunk(), &b"world"[..]);
+ /// ```
+ ///
+ /// # Implementer notes
+ ///
+ /// This function should never panic. Once the end of the buffer is reached,
+ /// i.e., `Buf::remaining` returns 0, calls to `chunk()` should return an
+ /// empty slice.
+ // The `chunk` method was previously called `bytes`. This alias makes the rename
+ // more easily discoverable.
+ #[cfg_attr(docsrs, doc(alias = "bytes"))]
+ fn chunk(&self) -> &[u8];
+
+ /// Fills `dst` with potentially multiple slices starting at `self`'s
+ /// current position.
+ ///
+ /// If the `Buf` is backed by disjoint slices of bytes, `chunk_vectored` enables
+ /// fetching more than one slice at once. `dst` is a slice of `IoSlice`
+ /// references, enabling the slice to be directly used with [`writev`]
+ /// without any further conversion. The sum of the lengths of all the
+ /// buffers in `dst` will be less than or equal to `Buf::remaining()`.
+ ///
+ /// The entries in `dst` will be overwritten, but the data **contained** by
+ /// the slices **will not** be modified. If `chunk_vectored` does not fill every
+ /// entry in `dst`, then `dst` is guaranteed to contain all remaining slices
+ /// in `self.
+ ///
+ /// This is a lower level function. Most operations are done with other
+ /// functions.
+ ///
+ /// # Implementer notes
+ ///
+ /// This function should never panic. Once the end of the buffer is reached,
+ /// i.e., `Buf::remaining` returns 0, calls to `chunk_vectored` must return 0
+ /// without mutating `dst`.
+ ///
+ /// Implementations should also take care to properly handle being called
+ /// with `dst` being a zero length slice.
+ ///
+ /// [`writev`]: http://man7.org/linux/man-pages/man2/readv.2.html
+ #[cfg(feature = "std")]
+ #[cfg_attr(docsrs, doc(cfg(feature = "std")))]
+ fn chunks_vectored<'a>(&'a self, dst: &mut [IoSlice<'a>]) -> usize {
+ if dst.is_empty() {
+ return 0;
+ }
+
+ if self.has_remaining() {
+ dst[0] = IoSlice::new(self.chunk());
+ 1
+ } else {
+ 0
+ }
+ }
+
+ /// Advance the internal cursor of the Buf
+ ///
+ /// The next call to `chunk()` will return a slice starting `cnt` bytes
+ /// further into the underlying buffer.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"hello world"[..];
+ ///
+ /// assert_eq!(buf.chunk(), &b"hello world"[..]);
+ ///
+ /// buf.advance(6);
+ ///
+ /// assert_eq!(buf.chunk(), &b"world"[..]);
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function **may** panic if `cnt > self.remaining()`.
+ ///
+ /// # Implementer notes
+ ///
+ /// It is recommended for implementations of `advance` to panic if `cnt >
+ /// self.remaining()`. If the implementation does not panic, the call must
+ /// behave as if `cnt == self.remaining()`.
+ ///
+ /// A call with `cnt == 0` should never panic and be a no-op.
+ fn advance(&mut self, cnt: usize);
+
+ /// Returns true if there are any more bytes to consume
+ ///
+ /// This is equivalent to `self.remaining() != 0`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"a"[..];
+ ///
+ /// assert!(buf.has_remaining());
+ ///
+ /// buf.get_u8();
+ ///
+ /// assert!(!buf.has_remaining());
+ /// ```
+ fn has_remaining(&self) -> bool {
+ self.remaining() > 0
+ }
+
+ /// Copies bytes from `self` into `dst`.
+ ///
+ /// The cursor is advanced by the number of bytes copied. `self` must have
+ /// enough remaining bytes to fill `dst`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"hello world"[..];
+ /// let mut dst = [0; 5];
+ ///
+ /// buf.copy_to_slice(&mut dst);
+ /// assert_eq!(&b"hello"[..], &dst);
+ /// assert_eq!(6, buf.remaining());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if `self.remaining() < dst.len()`
+ fn copy_to_slice(&mut self, dst: &mut [u8]) {
+ let mut off = 0;
+
+ assert!(self.remaining() >= dst.len());
+
+ while off < dst.len() {
+ let cnt;
+
+ unsafe {
+ let src = self.chunk();
+ cnt = cmp::min(src.len(), dst.len() - off);
+
+ ptr::copy_nonoverlapping(src.as_ptr(), dst[off..].as_mut_ptr(), cnt);
+
+ off += cnt;
+ }
+
+ self.advance(cnt);
+ }
+ }
+
+ /// Gets an unsigned 8 bit integer from `self`.
+ ///
+ /// The current position is advanced by 1.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x08 hello"[..];
+ /// assert_eq!(8, buf.get_u8());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is no more remaining data in `self`.
+ fn get_u8(&mut self) -> u8 {
+ assert!(self.remaining() >= 1);
+ let ret = self.chunk()[0];
+ self.advance(1);
+ ret
+ }
+
+ /// Gets a signed 8 bit integer from `self`.
+ ///
+ /// The current position is advanced by 1.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x08 hello"[..];
+ /// assert_eq!(8, buf.get_i8());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is no more remaining data in `self`.
+ fn get_i8(&mut self) -> i8 {
+ assert!(self.remaining() >= 1);
+ let ret = self.chunk()[0] as i8;
+ self.advance(1);
+ ret
+ }
+
+ /// Gets an unsigned 16 bit integer from `self` in big-endian byte order.
+ ///
+ /// The current position is advanced by 2.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x08\x09 hello"[..];
+ /// assert_eq!(0x0809, buf.get_u16());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_u16(&mut self) -> u16 {
+ buf_get_impl!(self, u16::from_be_bytes);
+ }
+
+ /// Gets an unsigned 16 bit integer from `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by 2.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x09\x08 hello"[..];
+ /// assert_eq!(0x0809, buf.get_u16_le());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_u16_le(&mut self) -> u16 {
+ buf_get_impl!(self, u16::from_le_bytes);
+ }
+
+ /// Gets an unsigned 16 bit integer from `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by 2.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf: &[u8] = match cfg!(target_endian = "big") {
+ /// true => b"\x08\x09 hello",
+ /// false => b"\x09\x08 hello",
+ /// };
+ /// assert_eq!(0x0809, buf.get_u16_ne());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_u16_ne(&mut self) -> u16 {
+ buf_get_impl!(self, u16::from_ne_bytes);
+ }
+
+ /// Gets a signed 16 bit integer from `self` in big-endian byte order.
+ ///
+ /// The current position is advanced by 2.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x08\x09 hello"[..];
+ /// assert_eq!(0x0809, buf.get_i16());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_i16(&mut self) -> i16 {
+ buf_get_impl!(self, i16::from_be_bytes);
+ }
+
+ /// Gets a signed 16 bit integer from `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by 2.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x09\x08 hello"[..];
+ /// assert_eq!(0x0809, buf.get_i16_le());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_i16_le(&mut self) -> i16 {
+ buf_get_impl!(self, i16::from_le_bytes);
+ }
+
+ /// Gets a signed 16 bit integer from `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by 2.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf: &[u8] = match cfg!(target_endian = "big") {
+ /// true => b"\x08\x09 hello",
+ /// false => b"\x09\x08 hello",
+ /// };
+ /// assert_eq!(0x0809, buf.get_i16_ne());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_i16_ne(&mut self) -> i16 {
+ buf_get_impl!(self, i16::from_ne_bytes);
+ }
+
+ /// Gets an unsigned 32 bit integer from `self` in the big-endian byte order.
+ ///
+ /// The current position is advanced by 4.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x08\x09\xA0\xA1 hello"[..];
+ /// assert_eq!(0x0809A0A1, buf.get_u32());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_u32(&mut self) -> u32 {
+ buf_get_impl!(self, u32::from_be_bytes);
+ }
+
+ /// Gets an unsigned 32 bit integer from `self` in the little-endian byte order.
+ ///
+ /// The current position is advanced by 4.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\xA1\xA0\x09\x08 hello"[..];
+ /// assert_eq!(0x0809A0A1, buf.get_u32_le());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_u32_le(&mut self) -> u32 {
+ buf_get_impl!(self, u32::from_le_bytes);
+ }
+
+ /// Gets an unsigned 32 bit integer from `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by 4.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf: &[u8] = match cfg!(target_endian = "big") {
+ /// true => b"\x08\x09\xA0\xA1 hello",
+ /// false => b"\xA1\xA0\x09\x08 hello",
+ /// };
+ /// assert_eq!(0x0809A0A1, buf.get_u32_ne());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_u32_ne(&mut self) -> u32 {
+ buf_get_impl!(self, u32::from_ne_bytes);
+ }
+
+ /// Gets a signed 32 bit integer from `self` in big-endian byte order.
+ ///
+ /// The current position is advanced by 4.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x08\x09\xA0\xA1 hello"[..];
+ /// assert_eq!(0x0809A0A1, buf.get_i32());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_i32(&mut self) -> i32 {
+ buf_get_impl!(self, i32::from_be_bytes);
+ }
+
+ /// Gets a signed 32 bit integer from `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by 4.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\xA1\xA0\x09\x08 hello"[..];
+ /// assert_eq!(0x0809A0A1, buf.get_i32_le());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_i32_le(&mut self) -> i32 {
+ buf_get_impl!(self, i32::from_le_bytes);
+ }
+
+ /// Gets a signed 32 bit integer from `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by 4.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf: &[u8] = match cfg!(target_endian = "big") {
+ /// true => b"\x08\x09\xA0\xA1 hello",
+ /// false => b"\xA1\xA0\x09\x08 hello",
+ /// };
+ /// assert_eq!(0x0809A0A1, buf.get_i32_ne());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_i32_ne(&mut self) -> i32 {
+ buf_get_impl!(self, i32::from_ne_bytes);
+ }
+
+ /// Gets an unsigned 64 bit integer from `self` in big-endian byte order.
+ ///
+ /// The current position is advanced by 8.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x01\x02\x03\x04\x05\x06\x07\x08 hello"[..];
+ /// assert_eq!(0x0102030405060708, buf.get_u64());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_u64(&mut self) -> u64 {
+ buf_get_impl!(self, u64::from_be_bytes);
+ }
+
+ /// Gets an unsigned 64 bit integer from `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by 8.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x08\x07\x06\x05\x04\x03\x02\x01 hello"[..];
+ /// assert_eq!(0x0102030405060708, buf.get_u64_le());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_u64_le(&mut self) -> u64 {
+ buf_get_impl!(self, u64::from_le_bytes);
+ }
+
+ /// Gets an unsigned 64 bit integer from `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by 8.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf: &[u8] = match cfg!(target_endian = "big") {
+ /// true => b"\x01\x02\x03\x04\x05\x06\x07\x08 hello",
+ /// false => b"\x08\x07\x06\x05\x04\x03\x02\x01 hello",
+ /// };
+ /// assert_eq!(0x0102030405060708, buf.get_u64_ne());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_u64_ne(&mut self) -> u64 {
+ buf_get_impl!(self, u64::from_ne_bytes);
+ }
+
+ /// Gets a signed 64 bit integer from `self` in big-endian byte order.
+ ///
+ /// The current position is advanced by 8.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x01\x02\x03\x04\x05\x06\x07\x08 hello"[..];
+ /// assert_eq!(0x0102030405060708, buf.get_i64());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_i64(&mut self) -> i64 {
+ buf_get_impl!(self, i64::from_be_bytes);
+ }
+
+ /// Gets a signed 64 bit integer from `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by 8.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x08\x07\x06\x05\x04\x03\x02\x01 hello"[..];
+ /// assert_eq!(0x0102030405060708, buf.get_i64_le());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_i64_le(&mut self) -> i64 {
+ buf_get_impl!(self, i64::from_le_bytes);
+ }
+
+ /// Gets a signed 64 bit integer from `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by 8.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf: &[u8] = match cfg!(target_endian = "big") {
+ /// true => b"\x01\x02\x03\x04\x05\x06\x07\x08 hello",
+ /// false => b"\x08\x07\x06\x05\x04\x03\x02\x01 hello",
+ /// };
+ /// assert_eq!(0x0102030405060708, buf.get_i64_ne());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_i64_ne(&mut self) -> i64 {
+ buf_get_impl!(self, i64::from_ne_bytes);
+ }
+
+ /// Gets an unsigned 128 bit integer from `self` in big-endian byte order.
+ ///
+ /// The current position is advanced by 16.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16 hello"[..];
+ /// assert_eq!(0x01020304050607080910111213141516, buf.get_u128());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_u128(&mut self) -> u128 {
+ buf_get_impl!(self, u128::from_be_bytes);
+ }
+
+ /// Gets an unsigned 128 bit integer from `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by 16.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02\x01 hello"[..];
+ /// assert_eq!(0x01020304050607080910111213141516, buf.get_u128_le());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_u128_le(&mut self) -> u128 {
+ buf_get_impl!(self, u128::from_le_bytes);
+ }
+
+ /// Gets an unsigned 128 bit integer from `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by 16.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf: &[u8] = match cfg!(target_endian = "big") {
+ /// true => b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16 hello",
+ /// false => b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02\x01 hello",
+ /// };
+ /// assert_eq!(0x01020304050607080910111213141516, buf.get_u128_ne());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_u128_ne(&mut self) -> u128 {
+ buf_get_impl!(self, u128::from_ne_bytes);
+ }
+
+ /// Gets a signed 128 bit integer from `self` in big-endian byte order.
+ ///
+ /// The current position is advanced by 16.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16 hello"[..];
+ /// assert_eq!(0x01020304050607080910111213141516, buf.get_i128());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_i128(&mut self) -> i128 {
+ buf_get_impl!(self, i128::from_be_bytes);
+ }
+
+ /// Gets a signed 128 bit integer from `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by 16.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02\x01 hello"[..];
+ /// assert_eq!(0x01020304050607080910111213141516, buf.get_i128_le());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_i128_le(&mut self) -> i128 {
+ buf_get_impl!(self, i128::from_le_bytes);
+ }
+
+ /// Gets a signed 128 bit integer from `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by 16.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf: &[u8] = match cfg!(target_endian = "big") {
+ /// true => b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16 hello",
+ /// false => b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02\x01 hello",
+ /// };
+ /// assert_eq!(0x01020304050607080910111213141516, buf.get_i128_ne());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_i128_ne(&mut self) -> i128 {
+ buf_get_impl!(self, i128::from_ne_bytes);
+ }
+
+ /// Gets an unsigned n-byte integer from `self` in big-endian byte order.
+ ///
+ /// The current position is advanced by `nbytes`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x01\x02\x03 hello"[..];
+ /// assert_eq!(0x010203, buf.get_uint(3));
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_uint(&mut self, nbytes: usize) -> u64 {
+ buf_get_impl!(be => self, u64, nbytes);
+ }
+
+ /// Gets an unsigned n-byte integer from `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by `nbytes`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x03\x02\x01 hello"[..];
+ /// assert_eq!(0x010203, buf.get_uint_le(3));
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_uint_le(&mut self, nbytes: usize) -> u64 {
+ buf_get_impl!(le => self, u64, nbytes);
+ }
+
+ /// Gets an unsigned n-byte integer from `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by `nbytes`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf: &[u8] = match cfg!(target_endian = "big") {
+ /// true => b"\x01\x02\x03 hello",
+ /// false => b"\x03\x02\x01 hello",
+ /// };
+ /// assert_eq!(0x010203, buf.get_uint_ne(3));
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_uint_ne(&mut self, nbytes: usize) -> u64 {
+ if cfg!(target_endian = "big") {
+ self.get_uint(nbytes)
+ } else {
+ self.get_uint_le(nbytes)
+ }
+ }
+
+ /// Gets a signed n-byte integer from `self` in big-endian byte order.
+ ///
+ /// The current position is advanced by `nbytes`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x01\x02\x03 hello"[..];
+ /// assert_eq!(0x010203, buf.get_int(3));
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_int(&mut self, nbytes: usize) -> i64 {
+ buf_get_impl!(be => self, i64, nbytes);
+ }
+
+ /// Gets a signed n-byte integer from `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by `nbytes`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x03\x02\x01 hello"[..];
+ /// assert_eq!(0x010203, buf.get_int_le(3));
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_int_le(&mut self, nbytes: usize) -> i64 {
+ buf_get_impl!(le => self, i64, nbytes);
+ }
+
+ /// Gets a signed n-byte integer from `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by `nbytes`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf: &[u8] = match cfg!(target_endian = "big") {
+ /// true => b"\x01\x02\x03 hello",
+ /// false => b"\x03\x02\x01 hello",
+ /// };
+ /// assert_eq!(0x010203, buf.get_int_ne(3));
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_int_ne(&mut self, nbytes: usize) -> i64 {
+ if cfg!(target_endian = "big") {
+ self.get_int(nbytes)
+ } else {
+ self.get_int_le(nbytes)
+ }
+ }
+
+ /// Gets an IEEE754 single-precision (4 bytes) floating point number from
+ /// `self` in big-endian byte order.
+ ///
+ /// The current position is advanced by 4.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x3F\x99\x99\x9A hello"[..];
+ /// assert_eq!(1.2f32, buf.get_f32());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_f32(&mut self) -> f32 {
+ f32::from_bits(Self::get_u32(self))
+ }
+
+ /// Gets an IEEE754 single-precision (4 bytes) floating point number from
+ /// `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by 4.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x9A\x99\x99\x3F hello"[..];
+ /// assert_eq!(1.2f32, buf.get_f32_le());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_f32_le(&mut self) -> f32 {
+ f32::from_bits(Self::get_u32_le(self))
+ }
+
+ /// Gets an IEEE754 single-precision (4 bytes) floating point number from
+ /// `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by 4.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf: &[u8] = match cfg!(target_endian = "big") {
+ /// true => b"\x3F\x99\x99\x9A hello",
+ /// false => b"\x9A\x99\x99\x3F hello",
+ /// };
+ /// assert_eq!(1.2f32, buf.get_f32_ne());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_f32_ne(&mut self) -> f32 {
+ f32::from_bits(Self::get_u32_ne(self))
+ }
+
+ /// Gets an IEEE754 double-precision (8 bytes) floating point number from
+ /// `self` in big-endian byte order.
+ ///
+ /// The current position is advanced by 8.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x3F\xF3\x33\x33\x33\x33\x33\x33 hello"[..];
+ /// assert_eq!(1.2f64, buf.get_f64());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_f64(&mut self) -> f64 {
+ f64::from_bits(Self::get_u64(self))
+ }
+
+ /// Gets an IEEE754 double-precision (8 bytes) floating point number from
+ /// `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by 8.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf = &b"\x33\x33\x33\x33\x33\x33\xF3\x3F hello"[..];
+ /// assert_eq!(1.2f64, buf.get_f64_le());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_f64_le(&mut self) -> f64 {
+ f64::from_bits(Self::get_u64_le(self))
+ }
+
+ /// Gets an IEEE754 double-precision (8 bytes) floating point number from
+ /// `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by 8.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let mut buf: &[u8] = match cfg!(target_endian = "big") {
+ /// true => b"\x3F\xF3\x33\x33\x33\x33\x33\x33 hello",
+ /// false => b"\x33\x33\x33\x33\x33\x33\xF3\x3F hello",
+ /// };
+ /// assert_eq!(1.2f64, buf.get_f64_ne());
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining data in `self`.
+ fn get_f64_ne(&mut self) -> f64 {
+ f64::from_bits(Self::get_u64_ne(self))
+ }
+
+ /// Consumes `len` bytes inside self and returns new instance of `Bytes`
+ /// with this data.
+ ///
+ /// This function may be optimized by the underlying type to avoid actual
+ /// copies. For example, `Bytes` implementation will do a shallow copy
+ /// (ref-count increment).
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Buf;
+ ///
+ /// let bytes = (&b"hello world"[..]).copy_to_bytes(5);
+ /// assert_eq!(&bytes[..], &b"hello"[..]);
+ /// ```
+ fn copy_to_bytes(&mut self, len: usize) -> crate::Bytes {
+ use super::BufMut;
+
+ assert!(len <= self.remaining(), "`len` greater than remaining");
+
+ let mut ret = crate::BytesMut::with_capacity(len);
+ ret.put(self.take(len));
+ ret.freeze()
+ }
+
+ /// Creates an adaptor which will read at most `limit` bytes from `self`.
+ ///
+ /// This function returns a new instance of `Buf` which will read at most
+ /// `limit` bytes.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::{Buf, BufMut};
+ ///
+ /// let mut buf = b"hello world"[..].take(5);
+ /// let mut dst = vec![];
+ ///
+ /// dst.put(&mut buf);
+ /// assert_eq!(dst, b"hello");
+ ///
+ /// let mut buf = buf.into_inner();
+ /// dst.clear();
+ /// dst.put(&mut buf);
+ /// assert_eq!(dst, b" world");
+ /// ```
+ fn take(self, limit: usize) -> Take<Self>
+ 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<U: Buf>(self, next: U) -> Chain<Self, U>
+ 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<Self>
+ where
+ Self: Sized,
+ {
+ reader::new(self)
+ }
+}
+
+macro_rules! deref_forward_buf {
+ () => {
+ fn remaining(&self) -> usize {
+ (**self).remaining()
+ }
+
+ fn chunk(&self) -> &[u8] {
+ (**self).chunk()
+ }
+
+ #[cfg(feature = "std")]
+ fn chunks_vectored<'b>(&'b self, dst: &mut [IoSlice<'b>]) -> usize {
+ (**self).chunks_vectored(dst)
+ }
+
+ fn advance(&mut self, cnt: usize) {
+ (**self).advance(cnt)
+ }
+
+ fn has_remaining(&self) -> bool {
+ (**self).has_remaining()
+ }
+
+ fn copy_to_slice(&mut self, dst: &mut [u8]) {
+ (**self).copy_to_slice(dst)
+ }
+
+ fn get_u8(&mut self) -> u8 {
+ (**self).get_u8()
+ }
+
+ fn get_i8(&mut self) -> i8 {
+ (**self).get_i8()
+ }
+
+ fn get_u16(&mut self) -> u16 {
+ (**self).get_u16()
+ }
+
+ fn get_u16_le(&mut self) -> u16 {
+ (**self).get_u16_le()
+ }
+
+ fn get_u16_ne(&mut self) -> u16 {
+ (**self).get_u16_ne()
+ }
+
+ fn get_i16(&mut self) -> i16 {
+ (**self).get_i16()
+ }
+
+ fn get_i16_le(&mut self) -> i16 {
+ (**self).get_i16_le()
+ }
+
+ fn get_i16_ne(&mut self) -> i16 {
+ (**self).get_i16_ne()
+ }
+
+ fn get_u32(&mut self) -> u32 {
+ (**self).get_u32()
+ }
+
+ fn get_u32_le(&mut self) -> u32 {
+ (**self).get_u32_le()
+ }
+
+ fn get_u32_ne(&mut self) -> u32 {
+ (**self).get_u32_ne()
+ }
+
+ fn get_i32(&mut self) -> i32 {
+ (**self).get_i32()
+ }
+
+ fn get_i32_le(&mut self) -> i32 {
+ (**self).get_i32_le()
+ }
+
+ fn get_i32_ne(&mut self) -> i32 {
+ (**self).get_i32_ne()
+ }
+
+ fn get_u64(&mut self) -> u64 {
+ (**self).get_u64()
+ }
+
+ fn get_u64_le(&mut self) -> u64 {
+ (**self).get_u64_le()
+ }
+
+ fn get_u64_ne(&mut self) -> u64 {
+ (**self).get_u64_ne()
+ }
+
+ fn get_i64(&mut self) -> i64 {
+ (**self).get_i64()
+ }
+
+ fn get_i64_le(&mut self) -> i64 {
+ (**self).get_i64_le()
+ }
+
+ fn get_i64_ne(&mut self) -> i64 {
+ (**self).get_i64_ne()
+ }
+
+ fn get_uint(&mut self, nbytes: usize) -> u64 {
+ (**self).get_uint(nbytes)
+ }
+
+ fn get_uint_le(&mut self, nbytes: usize) -> u64 {
+ (**self).get_uint_le(nbytes)
+ }
+
+ fn get_uint_ne(&mut self, nbytes: usize) -> u64 {
+ (**self).get_uint_ne(nbytes)
+ }
+
+ fn get_int(&mut self, nbytes: usize) -> i64 {
+ (**self).get_int(nbytes)
+ }
+
+ fn get_int_le(&mut self, nbytes: usize) -> i64 {
+ (**self).get_int_le(nbytes)
+ }
+
+ fn get_int_ne(&mut self, nbytes: usize) -> i64 {
+ (**self).get_int_ne(nbytes)
+ }
+
+ fn copy_to_bytes(&mut self, len: usize) -> crate::Bytes {
+ (**self).copy_to_bytes(len)
+ }
+ };
+}
+
+impl<T: Buf + ?Sized> Buf for &mut T {
+ deref_forward_buf!();
+}
+
+impl<T: Buf + ?Sized> Buf for Box<T> {
+ deref_forward_buf!();
+}
+
+impl Buf for &[u8] {
+ #[inline]
+ fn remaining(&self) -> usize {
+ self.len()
+ }
+
+ #[inline]
+ fn chunk(&self) -> &[u8] {
+ self
+ }
+
+ #[inline]
+ fn advance(&mut self, cnt: usize) {
+ *self = &self[cnt..];
+ }
+}
+
+#[cfg(feature = "std")]
+impl<T: AsRef<[u8]>> Buf for std::io::Cursor<T> {
+ fn remaining(&self) -> usize {
+ let len = self.get_ref().as_ref().len();
+ let pos = self.position();
+
+ if pos >= len as u64 {
+ return 0;
+ }
+
+ len - pos as usize
+ }
+
+ fn chunk(&self) -> &[u8] {
+ let len = self.get_ref().as_ref().len();
+ let pos = self.position();
+
+ if pos >= len as u64 {
+ return &[];
+ }
+
+ &self.get_ref().as_ref()[pos as usize..]
+ }
+
+ fn advance(&mut self, cnt: usize) {
+ let pos = (self.position() as usize)
+ .checked_add(cnt)
+ .expect("overflow");
+
+ assert!(pos <= self.get_ref().as_ref().len());
+ self.set_position(pos as u64);
+ }
+}
+
+// The existence of this function makes the compiler catch if the Buf
+// trait is "object-safe" or not.
+fn _assert_trait_object(_b: &dyn Buf) {}
diff --git a/third_party/rust/bytes/src/buf/buf_mut.rs b/third_party/rust/bytes/src/buf/buf_mut.rs
new file mode 100644
index 0000000000..685fcc76b1
--- /dev/null
+++ b/third_party/rust/bytes/src/buf/buf_mut.rs
@@ -0,0 +1,1493 @@
+use crate::buf::{limit, Chain, Limit, UninitSlice};
+#[cfg(feature = "std")]
+use crate::buf::{writer, Writer};
+
+use core::{cmp, mem, ptr, usize};
+
+use alloc::{boxed::Box, vec::Vec};
+
+/// A trait for values that provide sequential write access to bytes.
+///
+/// Write bytes to a buffer
+///
+/// A buffer stores bytes in memory such that write operations are infallible.
+/// The underlying storage may or may not be in contiguous memory. A `BufMut`
+/// value is a cursor into the buffer. Writing to `BufMut` advances the cursor
+/// position.
+///
+/// The simplest `BufMut` is a `Vec<u8>`.
+///
+/// ```
+/// use bytes::BufMut;
+///
+/// let mut buf = vec![];
+///
+/// buf.put(&b"hello world"[..]);
+///
+/// assert_eq!(buf, b"hello world");
+/// ```
+pub unsafe trait BufMut {
+ /// Returns the number of bytes that can be written from the current
+ /// position until the end of the buffer is reached.
+ ///
+ /// This value is greater than or equal to the length of the slice returned
+ /// by `chunk_mut()`.
+ ///
+ /// Writing to a `BufMut` may involve allocating more memory on the fly.
+ /// Implementations may fail before reaching the number of bytes indicated
+ /// by this method if they encounter an allocation failure.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut dst = [0; 10];
+ /// let mut buf = &mut dst[..];
+ ///
+ /// let original_remaining = buf.remaining_mut();
+ /// buf.put(&b"hello"[..]);
+ ///
+ /// assert_eq!(original_remaining - 5, buf.remaining_mut());
+ /// ```
+ ///
+ /// # Implementer notes
+ ///
+ /// Implementations of `remaining_mut` should ensure that the return value
+ /// does not change unless a call is made to `advance_mut` or any other
+ /// function that is documented to change the `BufMut`'s current position.
+ ///
+ /// # Note
+ ///
+ /// `remaining_mut` may return value smaller than actual available space.
+ fn remaining_mut(&self) -> usize;
+
+ /// Advance the internal cursor of the BufMut
+ ///
+ /// The next call to `chunk_mut` will return a slice starting `cnt` bytes
+ /// further into the underlying buffer.
+ ///
+ /// This function is unsafe because there is no guarantee that the bytes
+ /// being advanced past have been initialized.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = Vec::with_capacity(16);
+ ///
+ /// // Write some data
+ /// buf.chunk_mut()[0..2].copy_from_slice(b"he");
+ /// unsafe { buf.advance_mut(2) };
+ ///
+ /// // write more bytes
+ /// buf.chunk_mut()[0..3].copy_from_slice(b"llo");
+ ///
+ /// unsafe { buf.advance_mut(3); }
+ ///
+ /// assert_eq!(5, buf.len());
+ /// assert_eq!(buf, b"hello");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function **may** panic if `cnt > self.remaining_mut()`.
+ ///
+ /// # Implementer notes
+ ///
+ /// It is recommended for implementations of `advance_mut` to panic if
+ /// `cnt > self.remaining_mut()`. If the implementation does not panic,
+ /// the call must behave as if `cnt == self.remaining_mut()`.
+ ///
+ /// A call with `cnt == 0` should never panic and be a no-op.
+ unsafe fn advance_mut(&mut self, cnt: usize);
+
+ /// Returns true if there is space in `self` for more bytes.
+ ///
+ /// This is equivalent to `self.remaining_mut() != 0`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut dst = [0; 5];
+ /// let mut buf = &mut dst[..];
+ ///
+ /// assert!(buf.has_remaining_mut());
+ ///
+ /// buf.put(&b"hello"[..]);
+ ///
+ /// assert!(!buf.has_remaining_mut());
+ /// ```
+ fn has_remaining_mut(&self) -> bool {
+ self.remaining_mut() > 0
+ }
+
+ /// Returns a mutable slice starting at the current BufMut position and of
+ /// length between 0 and `BufMut::remaining_mut()`. Note that this *can* be shorter than the
+ /// whole remainder of the buffer (this allows non-continuous implementation).
+ ///
+ /// This is a lower level function. Most operations are done with other
+ /// functions.
+ ///
+ /// The returned byte slice may represent uninitialized memory.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = Vec::with_capacity(16);
+ ///
+ /// unsafe {
+ /// // MaybeUninit::as_mut_ptr
+ /// buf.chunk_mut()[0..].as_mut_ptr().write(b'h');
+ /// buf.chunk_mut()[1..].as_mut_ptr().write(b'e');
+ ///
+ /// buf.advance_mut(2);
+ ///
+ /// buf.chunk_mut()[0..].as_mut_ptr().write(b'l');
+ /// buf.chunk_mut()[1..].as_mut_ptr().write(b'l');
+ /// buf.chunk_mut()[2..].as_mut_ptr().write(b'o');
+ ///
+ /// buf.advance_mut(3);
+ /// }
+ ///
+ /// assert_eq!(5, buf.len());
+ /// assert_eq!(buf, b"hello");
+ /// ```
+ ///
+ /// # Implementer notes
+ ///
+ /// This function should never panic. `chunk_mut` should return an empty
+ /// slice **if and only if** `remaining_mut()` returns 0. In other words,
+ /// `chunk_mut()` returning an empty slice implies that `remaining_mut()` will
+ /// return 0 and `remaining_mut()` returning 0 implies that `chunk_mut()` will
+ /// return an empty slice.
+ ///
+ /// This function may trigger an out-of-memory abort if it tries to allocate
+ /// memory and fails to do so.
+ // The `chunk_mut` method was previously called `bytes_mut`. This alias makes the
+ // rename more easily discoverable.
+ #[cfg_attr(docsrs, doc(alias = "bytes_mut"))]
+ fn chunk_mut(&mut self) -> &mut UninitSlice;
+
+ /// Transfer bytes into `self` from `src` and advance the cursor by the
+ /// number of bytes written.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ ///
+ /// buf.put_u8(b'h');
+ /// buf.put(&b"ello"[..]);
+ /// buf.put(&b" world"[..]);
+ ///
+ /// assert_eq!(buf, b"hello world");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// Panics if `self` does not have enough capacity to contain `src`.
+ fn put<T: super::Buf>(&mut self, mut src: T)
+ where
+ Self: Sized,
+ {
+ assert!(self.remaining_mut() >= src.remaining());
+
+ while src.has_remaining() {
+ let l;
+
+ unsafe {
+ let s = src.chunk();
+ let d = self.chunk_mut();
+ l = cmp::min(s.len(), d.len());
+
+ ptr::copy_nonoverlapping(s.as_ptr(), d.as_mut_ptr() as *mut u8, l);
+ }
+
+ src.advance(l);
+ unsafe {
+ self.advance_mut(l);
+ }
+ }
+ }
+
+ /// Transfer bytes into `self` from `src` and advance the cursor by the
+ /// number of bytes written.
+ ///
+ /// `self` must have enough remaining capacity to contain all of `src`.
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut dst = [0; 6];
+ ///
+ /// {
+ /// let mut buf = &mut dst[..];
+ /// buf.put_slice(b"hello");
+ ///
+ /// assert_eq!(1, buf.remaining_mut());
+ /// }
+ ///
+ /// assert_eq!(b"hello\0", &dst);
+ /// ```
+ fn put_slice(&mut self, src: &[u8]) {
+ let mut off = 0;
+
+ assert!(
+ self.remaining_mut() >= src.len(),
+ "buffer overflow; remaining = {}; src = {}",
+ self.remaining_mut(),
+ src.len()
+ );
+
+ while off < src.len() {
+ let cnt;
+
+ unsafe {
+ let dst = self.chunk_mut();
+ cnt = cmp::min(dst.len(), src.len() - off);
+
+ ptr::copy_nonoverlapping(src[off..].as_ptr(), dst.as_mut_ptr() as *mut u8, cnt);
+
+ off += cnt;
+ }
+
+ unsafe {
+ self.advance_mut(cnt);
+ }
+ }
+ }
+
+ /// Put `cnt` bytes `val` into `self`.
+ ///
+ /// Logically equivalent to calling `self.put_u8(val)` `cnt` times, but may work faster.
+ ///
+ /// `self` must have at least `cnt` remaining capacity.
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut dst = [0; 6];
+ ///
+ /// {
+ /// let mut buf = &mut dst[..];
+ /// buf.put_bytes(b'a', 4);
+ ///
+ /// assert_eq!(2, buf.remaining_mut());
+ /// }
+ ///
+ /// assert_eq!(b"aaaa\0\0", &dst);
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_bytes(&mut self, val: u8, cnt: usize) {
+ for _ in 0..cnt {
+ self.put_u8(val);
+ }
+ }
+
+ /// Writes an unsigned 8 bit integer to `self`.
+ ///
+ /// The current position is advanced by 1.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_u8(0x01);
+ /// assert_eq!(buf, b"\x01");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_u8(&mut self, n: u8) {
+ let src = [n];
+ self.put_slice(&src);
+ }
+
+ /// Writes a signed 8 bit integer to `self`.
+ ///
+ /// The current position is advanced by 1.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_i8(0x01);
+ /// assert_eq!(buf, b"\x01");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_i8(&mut self, n: i8) {
+ let src = [n as u8];
+ self.put_slice(&src)
+ }
+
+ /// Writes an unsigned 16 bit integer to `self` in big-endian byte order.
+ ///
+ /// The current position is advanced by 2.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_u16(0x0809);
+ /// assert_eq!(buf, b"\x08\x09");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_u16(&mut self, n: u16) {
+ self.put_slice(&n.to_be_bytes())
+ }
+
+ /// Writes an unsigned 16 bit integer to `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by 2.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_u16_le(0x0809);
+ /// assert_eq!(buf, b"\x09\x08");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_u16_le(&mut self, n: u16) {
+ self.put_slice(&n.to_le_bytes())
+ }
+
+ /// Writes an unsigned 16 bit integer to `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by 2.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_u16_ne(0x0809);
+ /// if cfg!(target_endian = "big") {
+ /// assert_eq!(buf, b"\x08\x09");
+ /// } else {
+ /// assert_eq!(buf, b"\x09\x08");
+ /// }
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_u16_ne(&mut self, n: u16) {
+ self.put_slice(&n.to_ne_bytes())
+ }
+
+ /// Writes a signed 16 bit integer to `self` in big-endian byte order.
+ ///
+ /// The current position is advanced by 2.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_i16(0x0809);
+ /// assert_eq!(buf, b"\x08\x09");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_i16(&mut self, n: i16) {
+ self.put_slice(&n.to_be_bytes())
+ }
+
+ /// Writes a signed 16 bit integer to `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by 2.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_i16_le(0x0809);
+ /// assert_eq!(buf, b"\x09\x08");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_i16_le(&mut self, n: i16) {
+ self.put_slice(&n.to_le_bytes())
+ }
+
+ /// Writes a signed 16 bit integer to `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by 2.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_i16_ne(0x0809);
+ /// if cfg!(target_endian = "big") {
+ /// assert_eq!(buf, b"\x08\x09");
+ /// } else {
+ /// assert_eq!(buf, b"\x09\x08");
+ /// }
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_i16_ne(&mut self, n: i16) {
+ self.put_slice(&n.to_ne_bytes())
+ }
+
+ /// Writes an unsigned 32 bit integer to `self` in big-endian byte order.
+ ///
+ /// The current position is advanced by 4.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_u32(0x0809A0A1);
+ /// assert_eq!(buf, b"\x08\x09\xA0\xA1");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_u32(&mut self, n: u32) {
+ self.put_slice(&n.to_be_bytes())
+ }
+
+ /// Writes an unsigned 32 bit integer to `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by 4.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_u32_le(0x0809A0A1);
+ /// assert_eq!(buf, b"\xA1\xA0\x09\x08");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_u32_le(&mut self, n: u32) {
+ self.put_slice(&n.to_le_bytes())
+ }
+
+ /// Writes an unsigned 32 bit integer to `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by 4.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_u32_ne(0x0809A0A1);
+ /// if cfg!(target_endian = "big") {
+ /// assert_eq!(buf, b"\x08\x09\xA0\xA1");
+ /// } else {
+ /// assert_eq!(buf, b"\xA1\xA0\x09\x08");
+ /// }
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_u32_ne(&mut self, n: u32) {
+ self.put_slice(&n.to_ne_bytes())
+ }
+
+ /// Writes a signed 32 bit integer to `self` in big-endian byte order.
+ ///
+ /// The current position is advanced by 4.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_i32(0x0809A0A1);
+ /// assert_eq!(buf, b"\x08\x09\xA0\xA1");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_i32(&mut self, n: i32) {
+ self.put_slice(&n.to_be_bytes())
+ }
+
+ /// Writes a signed 32 bit integer to `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by 4.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_i32_le(0x0809A0A1);
+ /// assert_eq!(buf, b"\xA1\xA0\x09\x08");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_i32_le(&mut self, n: i32) {
+ self.put_slice(&n.to_le_bytes())
+ }
+
+ /// Writes a signed 32 bit integer to `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by 4.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_i32_ne(0x0809A0A1);
+ /// if cfg!(target_endian = "big") {
+ /// assert_eq!(buf, b"\x08\x09\xA0\xA1");
+ /// } else {
+ /// assert_eq!(buf, b"\xA1\xA0\x09\x08");
+ /// }
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_i32_ne(&mut self, n: i32) {
+ self.put_slice(&n.to_ne_bytes())
+ }
+
+ /// Writes an unsigned 64 bit integer to `self` in the big-endian byte order.
+ ///
+ /// The current position is advanced by 8.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_u64(0x0102030405060708);
+ /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_u64(&mut self, n: u64) {
+ self.put_slice(&n.to_be_bytes())
+ }
+
+ /// Writes an unsigned 64 bit integer to `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by 8.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_u64_le(0x0102030405060708);
+ /// assert_eq!(buf, b"\x08\x07\x06\x05\x04\x03\x02\x01");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_u64_le(&mut self, n: u64) {
+ self.put_slice(&n.to_le_bytes())
+ }
+
+ /// Writes an unsigned 64 bit integer to `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by 8.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_u64_ne(0x0102030405060708);
+ /// if cfg!(target_endian = "big") {
+ /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08");
+ /// } else {
+ /// assert_eq!(buf, b"\x08\x07\x06\x05\x04\x03\x02\x01");
+ /// }
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_u64_ne(&mut self, n: u64) {
+ self.put_slice(&n.to_ne_bytes())
+ }
+
+ /// Writes a signed 64 bit integer to `self` in the big-endian byte order.
+ ///
+ /// The current position is advanced by 8.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_i64(0x0102030405060708);
+ /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_i64(&mut self, n: i64) {
+ self.put_slice(&n.to_be_bytes())
+ }
+
+ /// Writes a signed 64 bit integer to `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by 8.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_i64_le(0x0102030405060708);
+ /// assert_eq!(buf, b"\x08\x07\x06\x05\x04\x03\x02\x01");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_i64_le(&mut self, n: i64) {
+ self.put_slice(&n.to_le_bytes())
+ }
+
+ /// Writes a signed 64 bit integer to `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by 8.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_i64_ne(0x0102030405060708);
+ /// if cfg!(target_endian = "big") {
+ /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08");
+ /// } else {
+ /// assert_eq!(buf, b"\x08\x07\x06\x05\x04\x03\x02\x01");
+ /// }
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_i64_ne(&mut self, n: i64) {
+ self.put_slice(&n.to_ne_bytes())
+ }
+
+ /// Writes an unsigned 128 bit integer to `self` in the big-endian byte order.
+ ///
+ /// The current position is advanced by 16.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_u128(0x01020304050607080910111213141516);
+ /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_u128(&mut self, n: u128) {
+ self.put_slice(&n.to_be_bytes())
+ }
+
+ /// Writes an unsigned 128 bit integer to `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by 16.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_u128_le(0x01020304050607080910111213141516);
+ /// assert_eq!(buf, b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02\x01");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_u128_le(&mut self, n: u128) {
+ self.put_slice(&n.to_le_bytes())
+ }
+
+ /// Writes an unsigned 128 bit integer to `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by 16.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_u128_ne(0x01020304050607080910111213141516);
+ /// if cfg!(target_endian = "big") {
+ /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16");
+ /// } else {
+ /// assert_eq!(buf, b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02\x01");
+ /// }
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_u128_ne(&mut self, n: u128) {
+ self.put_slice(&n.to_ne_bytes())
+ }
+
+ /// Writes a signed 128 bit integer to `self` in the big-endian byte order.
+ ///
+ /// The current position is advanced by 16.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_i128(0x01020304050607080910111213141516);
+ /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_i128(&mut self, n: i128) {
+ self.put_slice(&n.to_be_bytes())
+ }
+
+ /// Writes a signed 128 bit integer to `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by 16.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_i128_le(0x01020304050607080910111213141516);
+ /// assert_eq!(buf, b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02\x01");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_i128_le(&mut self, n: i128) {
+ self.put_slice(&n.to_le_bytes())
+ }
+
+ /// Writes a signed 128 bit integer to `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by 16.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_i128_ne(0x01020304050607080910111213141516);
+ /// if cfg!(target_endian = "big") {
+ /// assert_eq!(buf, b"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x10\x11\x12\x13\x14\x15\x16");
+ /// } else {
+ /// assert_eq!(buf, b"\x16\x15\x14\x13\x12\x11\x10\x09\x08\x07\x06\x05\x04\x03\x02\x01");
+ /// }
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_i128_ne(&mut self, n: i128) {
+ self.put_slice(&n.to_ne_bytes())
+ }
+
+ /// Writes an unsigned n-byte integer to `self` in big-endian byte order.
+ ///
+ /// The current position is advanced by `nbytes`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_uint(0x010203, 3);
+ /// assert_eq!(buf, b"\x01\x02\x03");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_uint(&mut self, n: u64, nbytes: usize) {
+ self.put_slice(&n.to_be_bytes()[mem::size_of_val(&n) - nbytes..]);
+ }
+
+ /// Writes an unsigned n-byte integer to `self` in the little-endian byte order.
+ ///
+ /// The current position is advanced by `nbytes`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_uint_le(0x010203, 3);
+ /// assert_eq!(buf, b"\x03\x02\x01");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_uint_le(&mut self, n: u64, nbytes: usize) {
+ self.put_slice(&n.to_le_bytes()[0..nbytes]);
+ }
+
+ /// Writes an unsigned n-byte integer to `self` in the native-endian byte order.
+ ///
+ /// The current position is advanced by `nbytes`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_uint_ne(0x010203, 3);
+ /// if cfg!(target_endian = "big") {
+ /// assert_eq!(buf, b"\x01\x02\x03");
+ /// } else {
+ /// assert_eq!(buf, b"\x03\x02\x01");
+ /// }
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_uint_ne(&mut self, n: u64, nbytes: usize) {
+ if cfg!(target_endian = "big") {
+ self.put_uint(n, nbytes)
+ } else {
+ self.put_uint_le(n, nbytes)
+ }
+ }
+
+ /// Writes low `nbytes` of a signed integer to `self` in big-endian byte order.
+ ///
+ /// The current position is advanced by `nbytes`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_int(0x0504010203, 3);
+ /// assert_eq!(buf, b"\x01\x02\x03");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self` or if `nbytes` is greater than 8.
+ fn put_int(&mut self, n: i64, nbytes: usize) {
+ self.put_slice(&n.to_be_bytes()[mem::size_of_val(&n) - nbytes..]);
+ }
+
+ /// Writes low `nbytes` of a signed integer to `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by `nbytes`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_int_le(0x0504010203, 3);
+ /// assert_eq!(buf, b"\x03\x02\x01");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self` or if `nbytes` is greater than 8.
+ fn put_int_le(&mut self, n: i64, nbytes: usize) {
+ self.put_slice(&n.to_le_bytes()[0..nbytes]);
+ }
+
+ /// Writes low `nbytes` of a signed integer to `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by `nbytes`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_int_ne(0x010203, 3);
+ /// if cfg!(target_endian = "big") {
+ /// assert_eq!(buf, b"\x01\x02\x03");
+ /// } else {
+ /// assert_eq!(buf, b"\x03\x02\x01");
+ /// }
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self` or if `nbytes` is greater than 8.
+ fn put_int_ne(&mut self, n: i64, nbytes: usize) {
+ if cfg!(target_endian = "big") {
+ self.put_int(n, nbytes)
+ } else {
+ self.put_int_le(n, nbytes)
+ }
+ }
+
+ /// Writes an IEEE754 single-precision (4 bytes) floating point number to
+ /// `self` in big-endian byte order.
+ ///
+ /// The current position is advanced by 4.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_f32(1.2f32);
+ /// assert_eq!(buf, b"\x3F\x99\x99\x9A");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_f32(&mut self, n: f32) {
+ self.put_u32(n.to_bits());
+ }
+
+ /// Writes an IEEE754 single-precision (4 bytes) floating point number to
+ /// `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by 4.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_f32_le(1.2f32);
+ /// assert_eq!(buf, b"\x9A\x99\x99\x3F");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_f32_le(&mut self, n: f32) {
+ self.put_u32_le(n.to_bits());
+ }
+
+ /// Writes an IEEE754 single-precision (4 bytes) floating point number to
+ /// `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by 4.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_f32_ne(1.2f32);
+ /// if cfg!(target_endian = "big") {
+ /// assert_eq!(buf, b"\x3F\x99\x99\x9A");
+ /// } else {
+ /// assert_eq!(buf, b"\x9A\x99\x99\x3F");
+ /// }
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_f32_ne(&mut self, n: f32) {
+ self.put_u32_ne(n.to_bits());
+ }
+
+ /// Writes an IEEE754 double-precision (8 bytes) floating point number to
+ /// `self` in big-endian byte order.
+ ///
+ /// The current position is advanced by 8.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_f64(1.2f64);
+ /// assert_eq!(buf, b"\x3F\xF3\x33\x33\x33\x33\x33\x33");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_f64(&mut self, n: f64) {
+ self.put_u64(n.to_bits());
+ }
+
+ /// Writes an IEEE754 double-precision (8 bytes) floating point number to
+ /// `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by 8.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_f64_le(1.2f64);
+ /// assert_eq!(buf, b"\x33\x33\x33\x33\x33\x33\xF3\x3F");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_f64_le(&mut self, n: f64) {
+ self.put_u64_le(n.to_bits());
+ }
+
+ /// Writes an IEEE754 double-precision (8 bytes) floating point number to
+ /// `self` in native-endian byte order.
+ ///
+ /// The current position is advanced by 8.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_f64_ne(1.2f64);
+ /// if cfg!(target_endian = "big") {
+ /// assert_eq!(buf, b"\x3F\xF3\x33\x33\x33\x33\x33\x33");
+ /// } else {
+ /// assert_eq!(buf, b"\x33\x33\x33\x33\x33\x33\xF3\x3F");
+ /// }
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_f64_ne(&mut self, n: f64) {
+ self.put_u64_ne(n.to_bits());
+ }
+
+ /// Creates an adaptor which can write at most `limit` bytes to `self`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let arr = &mut [0u8; 128][..];
+ /// assert_eq!(arr.remaining_mut(), 128);
+ ///
+ /// let dst = arr.limit(10);
+ /// assert_eq!(dst.remaining_mut(), 10);
+ /// ```
+ fn limit(self, limit: usize) -> Limit<Self>
+ where
+ Self: Sized,
+ {
+ limit::new(self, limit)
+ }
+
+ /// Creates an adaptor which implements the `Write` trait for `self`.
+ ///
+ /// This function returns a new value which implements `Write` by adapting
+ /// the `Write` trait functions to the `BufMut` trait functions. Given that
+ /// `BufMut` operations are infallible, none of the `Write` functions will
+ /// return with `Err`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ /// use std::io::Write;
+ ///
+ /// let mut buf = vec![].writer();
+ ///
+ /// let num = buf.write(&b"hello world"[..]).unwrap();
+ /// assert_eq!(11, num);
+ ///
+ /// let buf = buf.into_inner();
+ ///
+ /// assert_eq!(*buf, b"hello world"[..]);
+ /// ```
+ #[cfg(feature = "std")]
+ #[cfg_attr(docsrs, doc(cfg(feature = "std")))]
+ fn writer(self) -> Writer<Self>
+ where
+ Self: Sized,
+ {
+ writer::new(self)
+ }
+
+ /// Creates an adapter which will chain this buffer with another.
+ ///
+ /// The returned `BufMut` instance will first write to all bytes from
+ /// `self`. Afterwards, it will write to `next`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut a = [0u8; 5];
+ /// let mut b = [0u8; 6];
+ ///
+ /// let mut chain = (&mut a[..]).chain_mut(&mut b[..]);
+ ///
+ /// chain.put_slice(b"hello world");
+ ///
+ /// assert_eq!(&a[..], b"hello");
+ /// assert_eq!(&b[..], b" world");
+ /// ```
+ fn chain_mut<U: BufMut>(self, next: U) -> Chain<Self, U>
+ where
+ Self: Sized,
+ {
+ Chain::new(self, next)
+ }
+}
+
+macro_rules! deref_forward_bufmut {
+ () => {
+ fn remaining_mut(&self) -> usize {
+ (**self).remaining_mut()
+ }
+
+ fn chunk_mut(&mut self) -> &mut UninitSlice {
+ (**self).chunk_mut()
+ }
+
+ unsafe fn advance_mut(&mut self, cnt: usize) {
+ (**self).advance_mut(cnt)
+ }
+
+ fn put_slice(&mut self, src: &[u8]) {
+ (**self).put_slice(src)
+ }
+
+ fn put_u8(&mut self, n: u8) {
+ (**self).put_u8(n)
+ }
+
+ fn put_i8(&mut self, n: i8) {
+ (**self).put_i8(n)
+ }
+
+ fn put_u16(&mut self, n: u16) {
+ (**self).put_u16(n)
+ }
+
+ fn put_u16_le(&mut self, n: u16) {
+ (**self).put_u16_le(n)
+ }
+
+ fn put_u16_ne(&mut self, n: u16) {
+ (**self).put_u16_ne(n)
+ }
+
+ fn put_i16(&mut self, n: i16) {
+ (**self).put_i16(n)
+ }
+
+ fn put_i16_le(&mut self, n: i16) {
+ (**self).put_i16_le(n)
+ }
+
+ fn put_i16_ne(&mut self, n: i16) {
+ (**self).put_i16_ne(n)
+ }
+
+ fn put_u32(&mut self, n: u32) {
+ (**self).put_u32(n)
+ }
+
+ fn put_u32_le(&mut self, n: u32) {
+ (**self).put_u32_le(n)
+ }
+
+ fn put_u32_ne(&mut self, n: u32) {
+ (**self).put_u32_ne(n)
+ }
+
+ fn put_i32(&mut self, n: i32) {
+ (**self).put_i32(n)
+ }
+
+ fn put_i32_le(&mut self, n: i32) {
+ (**self).put_i32_le(n)
+ }
+
+ fn put_i32_ne(&mut self, n: i32) {
+ (**self).put_i32_ne(n)
+ }
+
+ fn put_u64(&mut self, n: u64) {
+ (**self).put_u64(n)
+ }
+
+ fn put_u64_le(&mut self, n: u64) {
+ (**self).put_u64_le(n)
+ }
+
+ fn put_u64_ne(&mut self, n: u64) {
+ (**self).put_u64_ne(n)
+ }
+
+ fn put_i64(&mut self, n: i64) {
+ (**self).put_i64(n)
+ }
+
+ fn put_i64_le(&mut self, n: i64) {
+ (**self).put_i64_le(n)
+ }
+
+ fn put_i64_ne(&mut self, n: i64) {
+ (**self).put_i64_ne(n)
+ }
+ };
+}
+
+unsafe impl<T: BufMut + ?Sized> BufMut for &mut T {
+ deref_forward_bufmut!();
+}
+
+unsafe impl<T: BufMut + ?Sized> BufMut for Box<T> {
+ deref_forward_bufmut!();
+}
+
+unsafe impl BufMut for &mut [u8] {
+ #[inline]
+ fn remaining_mut(&self) -> usize {
+ self.len()
+ }
+
+ #[inline]
+ fn chunk_mut(&mut self) -> &mut UninitSlice {
+ // UninitSlice is repr(transparent), so safe to transmute
+ unsafe { &mut *(*self as *mut [u8] as *mut _) }
+ }
+
+ #[inline]
+ unsafe fn advance_mut(&mut self, cnt: usize) {
+ // Lifetime dance taken from `impl Write for &mut [u8]`.
+ let (_, b) = core::mem::replace(self, &mut []).split_at_mut(cnt);
+ *self = b;
+ }
+
+ #[inline]
+ fn put_slice(&mut self, src: &[u8]) {
+ self[..src.len()].copy_from_slice(src);
+ unsafe {
+ self.advance_mut(src.len());
+ }
+ }
+
+ fn put_bytes(&mut self, val: u8, cnt: usize) {
+ assert!(self.remaining_mut() >= cnt);
+ unsafe {
+ ptr::write_bytes(self.as_mut_ptr(), val, cnt);
+ self.advance_mut(cnt);
+ }
+ }
+}
+
+unsafe impl BufMut for Vec<u8> {
+ #[inline]
+ fn remaining_mut(&self) -> usize {
+ // A vector can never have more than isize::MAX bytes
+ core::isize::MAX as usize - self.len()
+ }
+
+ #[inline]
+ unsafe fn advance_mut(&mut self, cnt: usize) {
+ let len = self.len();
+ let remaining = self.capacity() - len;
+
+ assert!(
+ cnt <= remaining,
+ "cannot advance past `remaining_mut`: {:?} <= {:?}",
+ cnt,
+ remaining
+ );
+
+ self.set_len(len + cnt);
+ }
+
+ #[inline]
+ fn chunk_mut(&mut self) -> &mut UninitSlice {
+ if self.capacity() == self.len() {
+ self.reserve(64); // Grow the vec
+ }
+
+ let cap = self.capacity();
+ let len = self.len();
+
+ let ptr = self.as_mut_ptr();
+ unsafe { &mut UninitSlice::from_raw_parts_mut(ptr, cap)[len..] }
+ }
+
+ // Specialize these methods so they can skip checking `remaining_mut`
+ // and `advance_mut`.
+ fn put<T: super::Buf>(&mut self, mut src: T)
+ where
+ Self: Sized,
+ {
+ // In case the src isn't contiguous, reserve upfront
+ self.reserve(src.remaining());
+
+ while src.has_remaining() {
+ let l;
+
+ // a block to contain the src.bytes() borrow
+ {
+ let s = src.chunk();
+ l = s.len();
+ self.extend_from_slice(s);
+ }
+
+ src.advance(l);
+ }
+ }
+
+ #[inline]
+ fn put_slice(&mut self, src: &[u8]) {
+ self.extend_from_slice(src);
+ }
+
+ fn put_bytes(&mut self, val: u8, cnt: usize) {
+ let new_len = self.len().checked_add(cnt).unwrap();
+ self.resize(new_len, val);
+ }
+}
+
+// The existence of this function makes the compiler catch if the BufMut
+// trait is "object-safe" or not.
+fn _assert_trait_object(_b: &dyn BufMut) {}
diff --git a/third_party/rust/bytes/src/buf/chain.rs b/third_party/rust/bytes/src/buf/chain.rs
new file mode 100644
index 0000000000..78979a1231
--- /dev/null
+++ b/third_party/rust/bytes/src/buf/chain.rs
@@ -0,0 +1,242 @@
+use crate::buf::{IntoIter, UninitSlice};
+use crate::{Buf, BufMut, Bytes};
+
+#[cfg(feature = "std")]
+use std::io::IoSlice;
+
+/// A `Chain` sequences two buffers.
+///
+/// `Chain` is an adapter that links two underlying buffers and provides a
+/// continuous view across both buffers. It is able to sequence either immutable
+/// buffers ([`Buf`] values) or mutable buffers ([`BufMut`] values).
+///
+/// This struct is generally created by calling [`Buf::chain`]. Please see that
+/// function's documentation for more detail.
+///
+/// # Examples
+///
+/// ```
+/// use bytes::{Bytes, Buf};
+///
+/// let mut buf = (&b"hello "[..])
+/// .chain(&b"world"[..]);
+///
+/// let full: Bytes = buf.copy_to_bytes(11);
+/// assert_eq!(full[..], b"hello world"[..]);
+/// ```
+///
+/// [`Buf::chain`]: trait.Buf.html#method.chain
+/// [`Buf`]: trait.Buf.html
+/// [`BufMut`]: trait.BufMut.html
+#[derive(Debug)]
+pub struct Chain<T, U> {
+ a: T,
+ b: U,
+}
+
+impl<T, U> Chain<T, U> {
+ /// Creates a new `Chain` sequencing the provided values.
+ pub(crate) fn new(a: T, b: U) -> Chain<T, U> {
+ 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<T, U> Buf for Chain<T, U>
+where
+ T: Buf,
+ U: Buf,
+{
+ fn remaining(&self) -> usize {
+ self.a.remaining().checked_add(self.b.remaining()).unwrap()
+ }
+
+ fn chunk(&self) -> &[u8] {
+ if self.a.has_remaining() {
+ self.a.chunk()
+ } else {
+ self.b.chunk()
+ }
+ }
+
+ fn advance(&mut self, mut cnt: usize) {
+ let a_rem = self.a.remaining();
+
+ if a_rem != 0 {
+ if a_rem >= cnt {
+ self.a.advance(cnt);
+ return;
+ }
+
+ // Consume what is left of a
+ self.a.advance(a_rem);
+
+ cnt -= a_rem;
+ }
+
+ self.b.advance(cnt);
+ }
+
+ #[cfg(feature = "std")]
+ fn chunks_vectored<'a>(&'a self, dst: &mut [IoSlice<'a>]) -> usize {
+ let mut n = self.a.chunks_vectored(dst);
+ n += self.b.chunks_vectored(&mut dst[n..]);
+ n
+ }
+
+ fn copy_to_bytes(&mut self, len: usize) -> Bytes {
+ let a_rem = self.a.remaining();
+ if a_rem >= len {
+ self.a.copy_to_bytes(len)
+ } else if a_rem == 0 {
+ self.b.copy_to_bytes(len)
+ } else {
+ assert!(
+ len - a_rem <= self.b.remaining(),
+ "`len` greater than remaining"
+ );
+ let mut ret = crate::BytesMut::with_capacity(len);
+ ret.put(&mut self.a);
+ ret.put((&mut self.b).take(len - a_rem));
+ ret.freeze()
+ }
+ }
+}
+
+unsafe impl<T, U> BufMut for Chain<T, U>
+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<T, U> IntoIterator for Chain<T, U>
+where
+ T: Buf,
+ U: Buf,
+{
+ type Item = u8;
+ type IntoIter = IntoIter<Chain<T, U>>;
+
+ fn into_iter(self) -> Self::IntoIter {
+ IntoIter::new(self)
+ }
+}
diff --git a/third_party/rust/bytes/src/buf/iter.rs b/third_party/rust/bytes/src/buf/iter.rs
new file mode 100644
index 0000000000..c694e3d418
--- /dev/null
+++ b/third_party/rust/bytes/src/buf/iter.rs
@@ -0,0 +1,130 @@
+use crate::Buf;
+
+/// Iterator over the bytes contained by the buffer.
+///
+/// # Examples
+///
+/// Basic usage:
+///
+/// ```
+/// use bytes::Bytes;
+///
+/// let buf = Bytes::from(&b"abc"[..]);
+/// let mut iter = buf.into_iter();
+///
+/// assert_eq!(iter.next(), Some(b'a'));
+/// assert_eq!(iter.next(), Some(b'b'));
+/// assert_eq!(iter.next(), Some(b'c'));
+/// assert_eq!(iter.next(), None);
+/// ```
+///
+/// [`iter`]: trait.Buf.html#method.iter
+/// [`Buf`]: trait.Buf.html
+#[derive(Debug)]
+pub struct IntoIter<T> {
+ inner: T,
+}
+
+impl<T> IntoIter<T> {
+ /// 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<T> {
+ 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<T: Buf> Iterator for IntoIter<T> {
+ type Item = u8;
+
+ fn next(&mut self) -> Option<u8> {
+ 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<usize>) {
+ let rem = self.inner.remaining();
+ (rem, Some(rem))
+ }
+}
+
+impl<T: Buf> ExactSizeIterator for IntoIter<T> {}
diff --git a/third_party/rust/bytes/src/buf/limit.rs b/third_party/rust/bytes/src/buf/limit.rs
new file mode 100644
index 0000000000..b422be5383
--- /dev/null
+++ b/third_party/rust/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<T> {
+ inner: T,
+ limit: usize,
+}
+
+pub(super) fn new<T>(inner: T, limit: usize) -> Limit<T> {
+ Limit { inner, limit }
+}
+
+impl<T> Limit<T> {
+ /// 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<T: BufMut> BufMut for Limit<T> {
+ 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/third_party/rust/bytes/src/buf/mod.rs b/third_party/rust/bytes/src/buf/mod.rs
new file mode 100644
index 0000000000..c4c0a5724a
--- /dev/null
+++ b/third_party/rust/bytes/src/buf/mod.rs
@@ -0,0 +1,41 @@
+//! Utilities for working with buffers.
+//!
+//! A buffer is any structure that contains a sequence of bytes. The bytes may
+//! or may not be stored in contiguous memory. This module contains traits used
+//! to abstract over buffers as well as utilities for working with buffer types.
+//!
+//! # `Buf`, `BufMut`
+//!
+//! These are the two foundational traits for abstractly working with buffers.
+//! They can be thought as iterators for byte structures. They offer additional
+//! performance over `Iterator` by providing an API optimized for byte slices.
+//!
+//! See [`Buf`] and [`BufMut`] for more details.
+//!
+//! [rope]: https://en.wikipedia.org/wiki/Rope_(data_structure)
+//! [`Buf`]: trait.Buf.html
+//! [`BufMut`]: trait.BufMut.html
+
+mod buf_impl;
+mod buf_mut;
+mod chain;
+mod iter;
+mod limit;
+#[cfg(feature = "std")]
+mod reader;
+mod take;
+mod uninit_slice;
+mod vec_deque;
+#[cfg(feature = "std")]
+mod writer;
+
+pub use self::buf_impl::Buf;
+pub use self::buf_mut::BufMut;
+pub use self::chain::Chain;
+pub use self::iter::IntoIter;
+pub use self::limit::Limit;
+pub use self::take::Take;
+pub use self::uninit_slice::UninitSlice;
+
+#[cfg(feature = "std")]
+pub use self::{reader::Reader, writer::Writer};
diff --git a/third_party/rust/bytes/src/buf/reader.rs b/third_party/rust/bytes/src/buf/reader.rs
new file mode 100644
index 0000000000..f2b4d98f71
--- /dev/null
+++ b/third_party/rust/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()`](trait.Buf.html#method.reader) for more
+/// details.
+#[derive(Debug)]
+pub struct Reader<B> {
+ buf: B,
+}
+
+pub fn new<B>(buf: B) -> Reader<B> {
+ Reader { buf }
+}
+
+impl<B: Buf> Reader<B> {
+ /// 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<B: Buf + Sized> io::Read for Reader<B> {
+ fn read(&mut self, dst: &mut [u8]) -> io::Result<usize> {
+ let len = cmp::min(self.buf.remaining(), dst.len());
+
+ Buf::copy_to_slice(&mut self.buf, &mut dst[0..len]);
+ Ok(len)
+ }
+}
+
+impl<B: Buf + Sized> io::BufRead for Reader<B> {
+ 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/third_party/rust/bytes/src/buf/take.rs b/third_party/rust/bytes/src/buf/take.rs
new file mode 100644
index 0000000000..d3cb10ab64
--- /dev/null
+++ b/third_party/rust/bytes/src/buf/take.rs
@@ -0,0 +1,155 @@
+use crate::{Buf, Bytes};
+
+use core::cmp;
+
+/// A `Buf` adapter which limits the bytes read from an underlying buffer.
+///
+/// This struct is generally created by calling `take()` on `Buf`. See
+/// documentation of [`take()`](trait.Buf.html#method.take) for more details.
+#[derive(Debug)]
+pub struct Take<T> {
+ inner: T,
+ limit: usize,
+}
+
+pub fn new<T>(inner: T, limit: usize) -> Take<T> {
+ Take { inner, limit }
+}
+
+impl<T> Take<T> {
+ /// 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<T: Buf> Buf for Take<T> {
+ fn remaining(&self) -> usize {
+ cmp::min(self.inner.remaining(), self.limit)
+ }
+
+ fn chunk(&self) -> &[u8] {
+ let bytes = self.inner.chunk();
+ &bytes[..cmp::min(bytes.len(), self.limit)]
+ }
+
+ fn advance(&mut self, cnt: usize) {
+ assert!(cnt <= self.limit);
+ self.inner.advance(cnt);
+ self.limit -= cnt;
+ }
+
+ fn copy_to_bytes(&mut self, len: usize) -> Bytes {
+ assert!(len <= self.remaining(), "`len` greater than remaining");
+
+ let r = self.inner.copy_to_bytes(len);
+ self.limit -= len;
+ r
+ }
+}
diff --git a/third_party/rust/bytes/src/buf/uninit_slice.rs b/third_party/rust/bytes/src/buf/uninit_slice.rs
new file mode 100644
index 0000000000..3161a147eb
--- /dev/null
+++ b/third_party/rust/bytes/src/buf/uninit_slice.rs
@@ -0,0 +1,213 @@
+use core::fmt;
+use core::mem::MaybeUninit;
+use core::ops::{
+ Index, IndexMut, Range, RangeFrom, RangeFull, RangeInclusive, RangeTo, RangeToInclusive,
+};
+
+/// Uninitialized byte slice.
+///
+/// Returned by `BufMut::chunk_mut()`, the referenced byte slice may be
+/// uninitialized. The wrapper provides safe access without introducing
+/// undefined behavior.
+///
+/// The safety invariants of this wrapper are:
+///
+/// 1. Reading from an `UninitSlice` is undefined behavior.
+/// 2. Writing uninitialized bytes to an `UninitSlice` is undefined behavior.
+///
+/// The difference between `&mut UninitSlice` and `&mut [MaybeUninit<u8>]` is
+/// that it is possible in safe code to write uninitialized bytes to an
+/// `&mut [MaybeUninit<u8>]`, which this type prohibits.
+#[repr(transparent)]
+pub struct UninitSlice([MaybeUninit<u8>]);
+
+impl UninitSlice {
+ pub(crate) fn from_slice(slice: &mut [MaybeUninit<u8>]) -> &mut UninitSlice {
+ unsafe { &mut *(slice as *mut [MaybeUninit<u8>] as *mut UninitSlice) }
+ }
+
+ /// Create a `&mut UninitSlice` from a pointer and a length.
+ ///
+ /// # Safety
+ ///
+ /// The caller must ensure that `ptr` references a valid memory region owned
+ /// by the caller representing a byte slice for the duration of `'a`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::buf::UninitSlice;
+ ///
+ /// let bytes = b"hello world".to_vec();
+ /// let ptr = bytes.as_ptr() as *mut _;
+ /// let len = bytes.len();
+ ///
+ /// let slice = unsafe { UninitSlice::from_raw_parts_mut(ptr, len) };
+ /// ```
+ #[inline]
+ pub unsafe fn from_raw_parts_mut<'a>(ptr: *mut u8, len: usize) -> &'a mut UninitSlice {
+ let maybe_init: &mut [MaybeUninit<u8>] =
+ core::slice::from_raw_parts_mut(ptr as *mut _, len);
+ Self::from_slice(maybe_init)
+ }
+
+ /// Write a single byte at the specified offset.
+ ///
+ /// # Panics
+ ///
+ /// The function panics if `index` is out of bounds.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::buf::UninitSlice;
+ ///
+ /// let mut data = [b'f', b'o', b'o'];
+ /// let slice = unsafe { UninitSlice::from_raw_parts_mut(data.as_mut_ptr(), 3) };
+ ///
+ /// slice.write_byte(0, b'b');
+ ///
+ /// assert_eq!(b"boo", &data[..]);
+ /// ```
+ #[inline]
+ pub fn write_byte(&mut self, index: usize, byte: u8) {
+ assert!(index < self.len());
+
+ unsafe { self[index..].as_mut_ptr().write(byte) }
+ }
+
+ /// Copies bytes from `src` into `self`.
+ ///
+ /// The length of `src` must be the same as `self`.
+ ///
+ /// # Panics
+ ///
+ /// The function panics if `src` has a different length than `self`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::buf::UninitSlice;
+ ///
+ /// let mut data = [b'f', b'o', b'o'];
+ /// let slice = unsafe { UninitSlice::from_raw_parts_mut(data.as_mut_ptr(), 3) };
+ ///
+ /// slice.copy_from_slice(b"bar");
+ ///
+ /// assert_eq!(b"bar", &data[..]);
+ /// ```
+ #[inline]
+ pub fn copy_from_slice(&mut self, src: &[u8]) {
+ use core::ptr;
+
+ assert_eq!(self.len(), src.len());
+
+ unsafe {
+ ptr::copy_nonoverlapping(src.as_ptr(), self.as_mut_ptr(), self.len());
+ }
+ }
+
+ /// Return a raw pointer to the slice's buffer.
+ ///
+ /// # Safety
+ ///
+ /// The caller **must not** read from the referenced memory and **must not**
+ /// write **uninitialized** bytes to the slice either.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut data = [0, 1, 2];
+ /// let mut slice = &mut data[..];
+ /// let ptr = BufMut::chunk_mut(&mut slice).as_mut_ptr();
+ /// ```
+ #[inline]
+ pub fn as_mut_ptr(&mut self) -> *mut u8 {
+ self.0.as_mut_ptr() as *mut _
+ }
+
+ /// Return a `&mut [MaybeUninit<u8>]` to this slice's buffer.
+ ///
+ /// # Safety
+ ///
+ /// The caller **must not** read from the referenced memory and **must not** write
+ /// **uninitialized** bytes to the slice either. This is because `BufMut` implementation
+ /// that created the `UninitSlice` knows which parts are initialized. Writing uninitalized
+ /// bytes to the slice may cause the `BufMut` to read those bytes and trigger undefined
+ /// behavior.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut data = [0, 1, 2];
+ /// let mut slice = &mut data[..];
+ /// unsafe {
+ /// let uninit_slice = BufMut::chunk_mut(&mut slice).as_uninit_slice_mut();
+ /// };
+ /// ```
+ #[inline]
+ pub unsafe fn as_uninit_slice_mut<'a>(&'a mut self) -> &'a mut [MaybeUninit<u8>] {
+ &mut *(self as *mut _ as *mut [MaybeUninit<u8>])
+ }
+
+ /// Returns the number of bytes in the slice.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut data = [0, 1, 2];
+ /// let mut slice = &mut data[..];
+ /// let len = BufMut::chunk_mut(&mut slice).len();
+ ///
+ /// assert_eq!(len, 3);
+ /// ```
+ #[inline]
+ pub fn len(&self) -> usize {
+ self.0.len()
+ }
+}
+
+impl fmt::Debug for UninitSlice {
+ fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+ fmt.debug_struct("UninitSlice[...]").finish()
+ }
+}
+
+macro_rules! impl_index {
+ ($($t:ty),*) => {
+ $(
+ impl Index<$t> for UninitSlice {
+ type Output = UninitSlice;
+
+ #[inline]
+ fn index(&self, index: $t) -> &UninitSlice {
+ let maybe_uninit: &[MaybeUninit<u8>] = &self.0[index];
+ unsafe { &*(maybe_uninit as *const [MaybeUninit<u8>] as *const UninitSlice) }
+ }
+ }
+
+ impl IndexMut<$t> for UninitSlice {
+ #[inline]
+ fn index_mut(&mut self, index: $t) -> &mut UninitSlice {
+ let maybe_uninit: &mut [MaybeUninit<u8>] = &mut self.0[index];
+ unsafe { &mut *(maybe_uninit as *mut [MaybeUninit<u8>] as *mut UninitSlice) }
+ }
+ }
+ )*
+ };
+}
+
+impl_index!(
+ Range<usize>,
+ RangeFrom<usize>,
+ RangeFull,
+ RangeInclusive<usize>,
+ RangeTo<usize>,
+ RangeToInclusive<usize>
+);
diff --git a/third_party/rust/bytes/src/buf/vec_deque.rs b/third_party/rust/bytes/src/buf/vec_deque.rs
new file mode 100644
index 0000000000..263167e83c
--- /dev/null
+++ b/third_party/rust/bytes/src/buf/vec_deque.rs
@@ -0,0 +1,22 @@
+use alloc::collections::VecDeque;
+
+use super::Buf;
+
+impl Buf for VecDeque<u8> {
+ fn remaining(&self) -> usize {
+ self.len()
+ }
+
+ fn chunk(&self) -> &[u8] {
+ let (s1, s2) = self.as_slices();
+ if s1.is_empty() {
+ s2
+ } else {
+ s1
+ }
+ }
+
+ fn advance(&mut self, cnt: usize) {
+ self.drain(..cnt);
+ }
+}
diff --git a/third_party/rust/bytes/src/buf/writer.rs b/third_party/rust/bytes/src/buf/writer.rs
new file mode 100644
index 0000000000..261d7cd091
--- /dev/null
+++ b/third_party/rust/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()`](trait.BufMut.html#method.writer) for more
+/// details.
+#[derive(Debug)]
+pub struct Writer<B> {
+ buf: B,
+}
+
+pub fn new<B>(buf: B) -> Writer<B> {
+ Writer { buf }
+}
+
+impl<B: BufMut> Writer<B> {
+ /// 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<B: BufMut + Sized> io::Write for Writer<B> {
+ fn write(&mut self, src: &[u8]) -> io::Result<usize> {
+ let n = cmp::min(self.buf.remaining_mut(), src.len());
+
+ self.buf.put(&src[0..n]);
+ Ok(n)
+ }
+
+ fn flush(&mut self) -> io::Result<()> {
+ Ok(())
+ }
+}
diff --git a/third_party/rust/bytes/src/bytes.rs b/third_party/rust/bytes/src/bytes.rs
new file mode 100644
index 0000000000..0404a72dba
--- /dev/null
+++ b/third_party/rust/bytes/src/bytes.rs
@@ -0,0 +1,1304 @@
+use core::iter::FromIterator;
+use core::ops::{Deref, RangeBounds};
+use core::{cmp, fmt, hash, mem, ptr, slice, usize};
+
+use alloc::{
+ alloc::{dealloc, Layout},
+ borrow::Borrow,
+ boxed::Box,
+ string::String,
+ vec::Vec,
+};
+
+use crate::buf::IntoIter;
+#[allow(unused)]
+use crate::loom::sync::atomic::AtomicMut;
+use crate::loom::sync::atomic::{AtomicPtr, AtomicUsize, Ordering};
+use crate::Buf;
+
+/// A cheaply cloneable and sliceable chunk of contiguous memory.
+///
+/// `Bytes` is an efficient container for storing and operating on contiguous
+/// slices of memory. It is intended for use primarily in networking code, but
+/// could have applications elsewhere as well.
+///
+/// `Bytes` values facilitate zero-copy network programming by allowing multiple
+/// `Bytes` objects to point to the same underlying memory.
+///
+/// `Bytes` does not have a single implementation. It is an interface, whose
+/// exact behavior is implemented through dynamic dispatch in several underlying
+/// implementations of `Bytes`.
+///
+/// All `Bytes` implementations must fulfill the following requirements:
+/// - They are cheaply cloneable and thereby shareable between an unlimited amount
+/// of components, for example by modifying a reference count.
+/// - Instances can be sliced to refer to a subset of the original buffer.
+///
+/// ```
+/// use bytes::Bytes;
+///
+/// let mut mem = Bytes::from("Hello world");
+/// let a = mem.slice(0..5);
+///
+/// assert_eq!(a, "Hello");
+///
+/// let b = mem.split_to(6);
+///
+/// assert_eq!(mem, "world");
+/// assert_eq!(b, "Hello ");
+/// ```
+///
+/// # Memory layout
+///
+/// The `Bytes` struct itself is fairly small, limited to 4 `usize` fields used
+/// to track information about which segment of the underlying memory the
+/// `Bytes` handle has access to.
+///
+/// `Bytes` keeps both a pointer to the shared state containing the full memory
+/// slice and a pointer to the start of the region visible by the handle.
+/// `Bytes` also tracks the length of its view into the memory.
+///
+/// # Sharing
+///
+/// `Bytes` contains a vtable, which allows implementations of `Bytes` to define
+/// how sharing/cloning is implemented in detail.
+/// When `Bytes::clone()` is called, `Bytes` will call the vtable function for
+/// cloning the backing storage in order to share it behind between multiple
+/// `Bytes` instances.
+///
+/// For `Bytes` implementations which refer to constant memory (e.g. created
+/// via `Bytes::from_static()`) the cloning implementation will be a no-op.
+///
+/// For `Bytes` implementations which point to a reference counted shared storage
+/// (e.g. an `Arc<[u8]>`), sharing will be implemented by increasing the
+/// reference count.
+///
+/// Due to this mechanism, multiple `Bytes` instances may point to the same
+/// shared memory region.
+/// Each `Bytes` instance can point to different sections within that
+/// memory region, and `Bytes` instances may or may not have overlapping views
+/// into the memory.
+///
+/// The following diagram visualizes a scenario where 2 `Bytes` instances make
+/// use of an `Arc`-based backing storage, and provide access to different views:
+///
+/// ```text
+///
+/// Arc ptrs ┌─────────┐
+/// ________________________ / │ Bytes 2 │
+/// / └─────────┘
+/// / ┌───────────┐ | |
+/// |_________/ │ Bytes 1 │ | |
+/// | └───────────┘ | |
+/// | | | ___/ data | tail
+/// | data | tail |/ |
+/// v v v v
+/// ┌─────┬─────┬───────────┬───────────────┬─────┐
+/// │ Arc │ │ │ │ │
+/// └─────┴─────┴───────────┴───────────────┴─────┘
+/// ```
+pub struct Bytes {
+ ptr: *const u8,
+ len: usize,
+ // inlined "trait object"
+ data: AtomicPtr<()>,
+ vtable: &'static Vtable,
+}
+
+pub(crate) struct Vtable {
+ /// fn(data, ptr, len)
+ pub clone: unsafe fn(&AtomicPtr<()>, *const u8, usize) -> Bytes,
+ /// fn(data, ptr, len)
+ ///
+ /// takes `Bytes` to value
+ pub to_vec: unsafe fn(&AtomicPtr<()>, *const u8, usize) -> Vec<u8>,
+ /// fn(data, ptr, len)
+ pub drop: unsafe fn(&mut AtomicPtr<()>, *const u8, usize),
+}
+
+impl Bytes {
+ /// Creates a new empty `Bytes`.
+ ///
+ /// This will not allocate and the returned `Bytes` handle will be empty.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Bytes;
+ ///
+ /// let b = Bytes::new();
+ /// assert_eq!(&b[..], b"");
+ /// ```
+ #[inline]
+ #[cfg(not(all(loom, test)))]
+ pub const fn new() -> Self {
+ // Make it a named const to work around
+ // "unsizing casts are not allowed in const fn"
+ const EMPTY: &[u8] = &[];
+ Bytes::from_static(EMPTY)
+ }
+
+ #[cfg(all(loom, test))]
+ pub fn new() -> Self {
+ const EMPTY: &[u8] = &[];
+ Bytes::from_static(EMPTY)
+ }
+
+ /// Creates a new `Bytes` from a static slice.
+ ///
+ /// The returned `Bytes` will point directly to the static slice. There is
+ /// no allocating or copying.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Bytes;
+ ///
+ /// let b = Bytes::from_static(b"hello");
+ /// assert_eq!(&b[..], b"hello");
+ /// ```
+ #[inline]
+ #[cfg(not(all(loom, test)))]
+ pub const fn from_static(bytes: &'static [u8]) -> Self {
+ Bytes {
+ ptr: bytes.as_ptr(),
+ len: bytes.len(),
+ data: AtomicPtr::new(ptr::null_mut()),
+ vtable: &STATIC_VTABLE,
+ }
+ }
+
+ #[cfg(all(loom, test))]
+ pub fn from_static(bytes: &'static [u8]) -> Self {
+ Bytes {
+ ptr: bytes.as_ptr(),
+ len: bytes.len(),
+ data: AtomicPtr::new(ptr::null_mut()),
+ vtable: &STATIC_VTABLE,
+ }
+ }
+
+ /// Returns the number of bytes contained in this `Bytes`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Bytes;
+ ///
+ /// let b = Bytes::from(&b"hello"[..]);
+ /// assert_eq!(b.len(), 5);
+ /// ```
+ #[inline]
+ pub const fn len(&self) -> usize {
+ self.len
+ }
+
+ /// Returns true if the `Bytes` has a length of 0.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Bytes;
+ ///
+ /// let b = Bytes::new();
+ /// assert!(b.is_empty());
+ /// ```
+ #[inline]
+ pub const fn is_empty(&self) -> bool {
+ self.len == 0
+ }
+
+ /// Creates `Bytes` instance from slice, by copying it.
+ pub fn copy_from_slice(data: &[u8]) -> Self {
+ data.to_vec().into()
+ }
+
+ /// Returns a slice of self for the provided range.
+ ///
+ /// This will increment the reference count for the underlying memory and
+ /// return a new `Bytes` handle set to the slice.
+ ///
+ /// This operation is `O(1)`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Bytes;
+ ///
+ /// let a = Bytes::from(&b"hello world"[..]);
+ /// let b = a.slice(2..5);
+ ///
+ /// assert_eq!(&b[..], b"llo");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// Requires that `begin <= end` and `end <= self.len()`, otherwise slicing
+ /// will panic.
+ pub fn slice(&self, range: impl RangeBounds<usize>) -> Self {
+ use core::ops::Bound;
+
+ let len = self.len();
+
+ let begin = match range.start_bound() {
+ Bound::Included(&n) => n,
+ Bound::Excluded(&n) => n + 1,
+ Bound::Unbounded => 0,
+ };
+
+ let end = match range.end_bound() {
+ Bound::Included(&n) => n.checked_add(1).expect("out of range"),
+ Bound::Excluded(&n) => n,
+ Bound::Unbounded => len,
+ };
+
+ assert!(
+ begin <= end,
+ "range start must not be greater than end: {:?} <= {:?}",
+ begin,
+ end,
+ );
+ assert!(
+ end <= len,
+ "range end out of bounds: {:?} <= {:?}",
+ end,
+ len,
+ );
+
+ if end == begin {
+ return Bytes::new();
+ }
+
+ let mut ret = self.clone();
+
+ ret.len = end - begin;
+ ret.ptr = unsafe { ret.ptr.add(begin) };
+
+ ret
+ }
+
+ /// Returns a slice of self that is equivalent to the given `subset`.
+ ///
+ /// When processing a `Bytes` buffer with other tools, one often gets a
+ /// `&[u8]` which is in fact a slice of the `Bytes`, i.e. a subset of it.
+ /// This function turns that `&[u8]` into another `Bytes`, as if one had
+ /// called `self.slice()` with the offsets that correspond to `subset`.
+ ///
+ /// This operation is `O(1)`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Bytes;
+ ///
+ /// let bytes = Bytes::from(&b"012345678"[..]);
+ /// let as_slice = bytes.as_ref();
+ /// let subset = &as_slice[2..6];
+ /// let subslice = bytes.slice_ref(&subset);
+ /// assert_eq!(&subslice[..], b"2345");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// Requires that the given `sub` slice is in fact contained within the
+ /// `Bytes` buffer; otherwise this function will panic.
+ pub fn slice_ref(&self, subset: &[u8]) -> Self {
+ // Empty slice and empty Bytes may have their pointers reset
+ // so explicitly allow empty slice to be a subslice of any slice.
+ if subset.is_empty() {
+ return Bytes::new();
+ }
+
+ let bytes_p = self.as_ptr() as usize;
+ let bytes_len = self.len();
+
+ let sub_p = subset.as_ptr() as usize;
+ let sub_len = subset.len();
+
+ assert!(
+ sub_p >= bytes_p,
+ "subset pointer ({:p}) is smaller than self pointer ({:p})",
+ subset.as_ptr(),
+ self.as_ptr(),
+ );
+ assert!(
+ sub_p + sub_len <= bytes_p + bytes_len,
+ "subset is out of bounds: self = ({:p}, {}), subset = ({:p}, {})",
+ self.as_ptr(),
+ bytes_len,
+ subset.as_ptr(),
+ sub_len,
+ );
+
+ let sub_offset = sub_p - bytes_p;
+
+ self.slice(sub_offset..(sub_offset + sub_len))
+ }
+
+ /// Splits the bytes into two at the given index.
+ ///
+ /// Afterwards `self` contains elements `[0, at)`, and the returned `Bytes`
+ /// contains elements `[at, len)`.
+ ///
+ /// This is an `O(1)` operation that just increases the reference count and
+ /// sets a few indices.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Bytes;
+ ///
+ /// let mut a = Bytes::from(&b"hello world"[..]);
+ /// let b = a.split_off(5);
+ ///
+ /// assert_eq!(&a[..], b"hello");
+ /// assert_eq!(&b[..], b" world");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// Panics if `at > len`.
+ #[must_use = "consider Bytes::truncate if you don't need the other half"]
+ pub fn split_off(&mut self, at: usize) -> Self {
+ assert!(
+ at <= self.len(),
+ "split_off out of bounds: {:?} <= {:?}",
+ at,
+ self.len(),
+ );
+
+ if at == self.len() {
+ return Bytes::new();
+ }
+
+ if at == 0 {
+ return mem::replace(self, Bytes::new());
+ }
+
+ let mut ret = self.clone();
+
+ self.len = at;
+
+ unsafe { ret.inc_start(at) };
+
+ ret
+ }
+
+ /// Splits the bytes into two at the given index.
+ ///
+ /// Afterwards `self` contains elements `[at, len)`, and the returned
+ /// `Bytes` contains elements `[0, at)`.
+ ///
+ /// This is an `O(1)` operation that just increases the reference count and
+ /// sets a few indices.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Bytes;
+ ///
+ /// let mut a = Bytes::from(&b"hello world"[..]);
+ /// let b = a.split_to(5);
+ ///
+ /// assert_eq!(&a[..], b" world");
+ /// assert_eq!(&b[..], b"hello");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// Panics if `at > len`.
+ #[must_use = "consider Bytes::advance if you don't need the other half"]
+ pub fn split_to(&mut self, at: usize) -> Self {
+ assert!(
+ at <= self.len(),
+ "split_to out of bounds: {:?} <= {:?}",
+ at,
+ self.len(),
+ );
+
+ if at == self.len() {
+ return mem::replace(self, Bytes::new());
+ }
+
+ if at == 0 {
+ return Bytes::new();
+ }
+
+ let mut ret = self.clone();
+
+ unsafe { self.inc_start(at) };
+
+ ret.len = at;
+ ret
+ }
+
+ /// Shortens the buffer, keeping the first `len` bytes and dropping the
+ /// rest.
+ ///
+ /// If `len` is greater than the buffer's current length, this has no
+ /// effect.
+ ///
+ /// The [`split_off`] method can emulate `truncate`, but this causes the
+ /// excess bytes to be returned instead of dropped.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Bytes;
+ ///
+ /// let mut buf = Bytes::from(&b"hello world"[..]);
+ /// buf.truncate(5);
+ /// assert_eq!(buf, b"hello"[..]);
+ /// ```
+ ///
+ /// [`split_off`]: #method.split_off
+ #[inline]
+ pub fn truncate(&mut self, len: usize) {
+ if len < self.len {
+ // The Vec "promotable" vtables do not store the capacity,
+ // so we cannot truncate while using this repr. We *have* to
+ // promote using `split_off` so the capacity can be stored.
+ if self.vtable as *const Vtable == &PROMOTABLE_EVEN_VTABLE
+ || self.vtable as *const Vtable == &PROMOTABLE_ODD_VTABLE
+ {
+ drop(self.split_off(len));
+ } else {
+ self.len = len;
+ }
+ }
+ }
+
+ /// Clears the buffer, removing all data.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::Bytes;
+ ///
+ /// let mut buf = Bytes::from(&b"hello world"[..]);
+ /// buf.clear();
+ /// assert!(buf.is_empty());
+ /// ```
+ #[inline]
+ pub fn clear(&mut self) {
+ self.truncate(0);
+ }
+
+ #[inline]
+ pub(crate) unsafe fn with_vtable(
+ ptr: *const u8,
+ len: usize,
+ data: AtomicPtr<()>,
+ vtable: &'static Vtable,
+ ) -> Bytes {
+ Bytes {
+ ptr,
+ len,
+ data,
+ vtable,
+ }
+ }
+
+ // private
+
+ #[inline]
+ fn as_slice(&self) -> &[u8] {
+ unsafe { slice::from_raw_parts(self.ptr, self.len) }
+ }
+
+ #[inline]
+ unsafe fn inc_start(&mut self, by: usize) {
+ // should already be asserted, but debug assert for tests
+ debug_assert!(self.len >= by, "internal: inc_start out of bounds");
+ self.len -= by;
+ self.ptr = self.ptr.add(by);
+ }
+}
+
+// Vtable must enforce this behavior
+unsafe impl Send for Bytes {}
+unsafe impl Sync for Bytes {}
+
+impl Drop for Bytes {
+ #[inline]
+ fn drop(&mut self) {
+ unsafe { (self.vtable.drop)(&mut self.data, self.ptr, self.len) }
+ }
+}
+
+impl Clone for Bytes {
+ #[inline]
+ fn clone(&self) -> Bytes {
+ unsafe { (self.vtable.clone)(&self.data, self.ptr, self.len) }
+ }
+}
+
+impl Buf for Bytes {
+ #[inline]
+ fn remaining(&self) -> usize {
+ self.len()
+ }
+
+ #[inline]
+ fn chunk(&self) -> &[u8] {
+ self.as_slice()
+ }
+
+ #[inline]
+ fn advance(&mut self, cnt: usize) {
+ assert!(
+ cnt <= self.len(),
+ "cannot advance past `remaining`: {:?} <= {:?}",
+ cnt,
+ self.len(),
+ );
+
+ unsafe {
+ self.inc_start(cnt);
+ }
+ }
+
+ fn copy_to_bytes(&mut self, len: usize) -> crate::Bytes {
+ if len == self.remaining() {
+ core::mem::replace(self, Bytes::new())
+ } else {
+ let ret = self.slice(..len);
+ self.advance(len);
+ ret
+ }
+ }
+}
+
+impl Deref for Bytes {
+ type Target = [u8];
+
+ #[inline]
+ fn deref(&self) -> &[u8] {
+ self.as_slice()
+ }
+}
+
+impl AsRef<[u8]> for Bytes {
+ #[inline]
+ fn as_ref(&self) -> &[u8] {
+ self.as_slice()
+ }
+}
+
+impl hash::Hash for Bytes {
+ fn hash<H>(&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<Bytes>;
+
+ 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<u8> for Bytes {
+ fn from_iter<T: IntoIterator<Item = u8>>(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<cmp::Ordering> {
+ 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<cmp::Ordering> {
+ self.as_slice().partial_cmp(other)
+ }
+}
+
+impl PartialEq<Bytes> for [u8] {
+ fn eq(&self, other: &Bytes) -> bool {
+ *other == *self
+ }
+}
+
+impl PartialOrd<Bytes> for [u8] {
+ fn partial_cmp(&self, other: &Bytes) -> Option<cmp::Ordering> {
+ <[u8] as PartialOrd<[u8]>>::partial_cmp(self, other)
+ }
+}
+
+impl PartialEq<str> for Bytes {
+ fn eq(&self, other: &str) -> bool {
+ self.as_slice() == other.as_bytes()
+ }
+}
+
+impl PartialOrd<str> for Bytes {
+ fn partial_cmp(&self, other: &str) -> Option<cmp::Ordering> {
+ self.as_slice().partial_cmp(other.as_bytes())
+ }
+}
+
+impl PartialEq<Bytes> for str {
+ fn eq(&self, other: &Bytes) -> bool {
+ *other == *self
+ }
+}
+
+impl PartialOrd<Bytes> for str {
+ fn partial_cmp(&self, other: &Bytes) -> Option<cmp::Ordering> {
+ <[u8] as PartialOrd<[u8]>>::partial_cmp(self.as_bytes(), other)
+ }
+}
+
+impl PartialEq<Vec<u8>> for Bytes {
+ fn eq(&self, other: &Vec<u8>) -> bool {
+ *self == other[..]
+ }
+}
+
+impl PartialOrd<Vec<u8>> for Bytes {
+ fn partial_cmp(&self, other: &Vec<u8>) -> Option<cmp::Ordering> {
+ self.as_slice().partial_cmp(&other[..])
+ }
+}
+
+impl PartialEq<Bytes> for Vec<u8> {
+ fn eq(&self, other: &Bytes) -> bool {
+ *other == *self
+ }
+}
+
+impl PartialOrd<Bytes> for Vec<u8> {
+ fn partial_cmp(&self, other: &Bytes) -> Option<cmp::Ordering> {
+ <[u8] as PartialOrd<[u8]>>::partial_cmp(self, other)
+ }
+}
+
+impl PartialEq<String> for Bytes {
+ fn eq(&self, other: &String) -> bool {
+ *self == other[..]
+ }
+}
+
+impl PartialOrd<String> for Bytes {
+ fn partial_cmp(&self, other: &String) -> Option<cmp::Ordering> {
+ self.as_slice().partial_cmp(other.as_bytes())
+ }
+}
+
+impl PartialEq<Bytes> for String {
+ fn eq(&self, other: &Bytes) -> bool {
+ *other == *self
+ }
+}
+
+impl PartialOrd<Bytes> for String {
+ fn partial_cmp(&self, other: &Bytes) -> Option<cmp::Ordering> {
+ <[u8] as PartialOrd<[u8]>>::partial_cmp(self.as_bytes(), other)
+ }
+}
+
+impl PartialEq<Bytes> for &[u8] {
+ fn eq(&self, other: &Bytes) -> bool {
+ *other == *self
+ }
+}
+
+impl PartialOrd<Bytes> for &[u8] {
+ fn partial_cmp(&self, other: &Bytes) -> Option<cmp::Ordering> {
+ <[u8] as PartialOrd<[u8]>>::partial_cmp(self, other)
+ }
+}
+
+impl PartialEq<Bytes> for &str {
+ fn eq(&self, other: &Bytes) -> bool {
+ *other == *self
+ }
+}
+
+impl PartialOrd<Bytes> for &str {
+ fn partial_cmp(&self, other: &Bytes) -> Option<cmp::Ordering> {
+ <[u8] as PartialOrd<[u8]>>::partial_cmp(self.as_bytes(), other)
+ }
+}
+
+impl<'a, T: ?Sized> PartialEq<&'a T> for Bytes
+where
+ Bytes: PartialEq<T>,
+{
+ fn eq(&self, other: &&'a T) -> bool {
+ *self == **other
+ }
+}
+
+impl<'a, T: ?Sized> PartialOrd<&'a T> for Bytes
+where
+ Bytes: PartialOrd<T>,
+{
+ fn partial_cmp(&self, other: &&'a T) -> Option<cmp::Ordering> {
+ 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<Vec<u8>> for Bytes {
+ fn from(vec: Vec<u8>) -> Bytes {
+ let mut vec = vec;
+ let ptr = vec.as_mut_ptr();
+ let len = vec.len();
+ let cap = vec.capacity();
+
+ // Avoid an extra allocation if possible.
+ if len == cap {
+ return Bytes::from(vec.into_boxed_slice());
+ }
+
+ let shared = Box::new(Shared {
+ buf: ptr,
+ cap,
+ ref_cnt: AtomicUsize::new(1),
+ });
+ mem::forget(vec);
+
+ let shared = Box::into_raw(shared);
+ // The pointer should be aligned, so this assert should
+ // always succeed.
+ debug_assert!(
+ 0 == (shared as usize & KIND_MASK),
+ "internal: Box<Shared> should have an aligned pointer",
+ );
+ Bytes {
+ ptr,
+ len,
+ data: AtomicPtr::new(shared as _),
+ vtable: &SHARED_VTABLE,
+ }
+ }
+}
+
+impl From<Box<[u8]>> 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<String> for Bytes {
+ fn from(s: String) -> Bytes {
+ Bytes::from(s.into_bytes())
+ }
+}
+
+impl From<Bytes> for Vec<u8> {
+ fn from(bytes: Bytes) -> Vec<u8> {
+ let bytes = mem::ManuallyDrop::new(bytes);
+ unsafe { (bytes.vtable.to_vec)(&bytes.data, bytes.ptr, bytes.len) }
+ }
+}
+
+// ===== impl Vtable =====
+
+impl fmt::Debug for Vtable {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ f.debug_struct("Vtable")
+ .field("clone", &(self.clone as *const ()))
+ .field("drop", &(self.drop as *const ()))
+ .finish()
+ }
+}
+
+// ===== impl StaticVtable =====
+
+const STATIC_VTABLE: Vtable = Vtable {
+ clone: static_clone,
+ to_vec: static_to_vec,
+ drop: static_drop,
+};
+
+unsafe fn static_clone(_: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Bytes {
+ let slice = slice::from_raw_parts(ptr, len);
+ Bytes::from_static(slice)
+}
+
+unsafe fn static_to_vec(_: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Vec<u8> {
+ let slice = slice::from_raw_parts(ptr, len);
+ slice.to_vec()
+}
+
+unsafe fn static_drop(_: &mut AtomicPtr<()>, _: *const u8, _: usize) {
+ // nothing to drop for &'static [u8]
+}
+
+// ===== impl PromotableVtable =====
+
+static PROMOTABLE_EVEN_VTABLE: Vtable = Vtable {
+ clone: promotable_even_clone,
+ to_vec: promotable_even_to_vec,
+ drop: promotable_even_drop,
+};
+
+static PROMOTABLE_ODD_VTABLE: Vtable = Vtable {
+ clone: promotable_odd_clone,
+ to_vec: promotable_odd_to_vec,
+ drop: promotable_odd_drop,
+};
+
+unsafe fn promotable_even_clone(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Bytes {
+ let shared = data.load(Ordering::Acquire);
+ let kind = shared as usize & KIND_MASK;
+
+ if kind == KIND_ARC {
+ shallow_clone_arc(shared.cast(), ptr, len)
+ } else {
+ debug_assert_eq!(kind, KIND_VEC);
+ let buf = ptr_map(shared.cast(), |addr| addr & !KIND_MASK);
+ shallow_clone_vec(data, shared, buf, ptr, len)
+ }
+}
+
+unsafe fn promotable_to_vec(
+ data: &AtomicPtr<()>,
+ ptr: *const u8,
+ len: usize,
+ f: fn(*mut ()) -> *mut u8,
+) -> Vec<u8> {
+ let shared = data.load(Ordering::Acquire);
+ let kind = shared as usize & KIND_MASK;
+
+ if kind == KIND_ARC {
+ shared_to_vec_impl(shared.cast(), ptr, len)
+ } else {
+ // If Bytes holds a Vec, then the offset must be 0.
+ debug_assert_eq!(kind, KIND_VEC);
+
+ let buf = f(shared);
+
+ let cap = (ptr as usize - buf as usize) + len;
+
+ // Copy back buffer
+ ptr::copy(ptr, buf, len);
+
+ Vec::from_raw_parts(buf, len, cap)
+ }
+}
+
+unsafe fn promotable_even_to_vec(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Vec<u8> {
+ promotable_to_vec(data, ptr, len, |shared| {
+ ptr_map(shared.cast(), |addr| addr & !KIND_MASK)
+ })
+}
+
+unsafe fn promotable_even_drop(data: &mut AtomicPtr<()>, ptr: *const u8, len: usize) {
+ data.with_mut(|shared| {
+ let shared = *shared;
+ let kind = shared as usize & KIND_MASK;
+
+ if kind == KIND_ARC {
+ release_shared(shared.cast());
+ } else {
+ debug_assert_eq!(kind, KIND_VEC);
+ let buf = ptr_map(shared.cast(), |addr| addr & !KIND_MASK);
+ free_boxed_slice(buf, ptr, len);
+ }
+ });
+}
+
+unsafe fn promotable_odd_clone(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Bytes {
+ let shared = data.load(Ordering::Acquire);
+ let kind = shared as usize & KIND_MASK;
+
+ if kind == KIND_ARC {
+ shallow_clone_arc(shared as _, ptr, len)
+ } else {
+ debug_assert_eq!(kind, KIND_VEC);
+ shallow_clone_vec(data, shared, shared.cast(), ptr, len)
+ }
+}
+
+unsafe fn promotable_odd_to_vec(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Vec<u8> {
+ promotable_to_vec(data, ptr, len, |shared| shared.cast())
+}
+
+unsafe fn promotable_odd_drop(data: &mut AtomicPtr<()>, ptr: *const u8, len: usize) {
+ data.with_mut(|shared| {
+ let shared = *shared;
+ let kind = shared as usize & KIND_MASK;
+
+ if kind == KIND_ARC {
+ release_shared(shared.cast());
+ } else {
+ debug_assert_eq!(kind, KIND_VEC);
+
+ free_boxed_slice(shared.cast(), ptr, len);
+ }
+ });
+}
+
+unsafe fn free_boxed_slice(buf: *mut u8, offset: *const u8, len: usize) {
+ let cap = (offset as usize - buf as usize) + len;
+ dealloc(buf, Layout::from_size_align(cap, 1).unwrap())
+}
+
+// ===== impl SharedVtable =====
+
+struct Shared {
+ // Holds arguments to dealloc upon Drop, but otherwise doesn't use them
+ buf: *mut u8,
+ cap: usize,
+ ref_cnt: AtomicUsize,
+}
+
+impl Drop for Shared {
+ fn drop(&mut self) {
+ unsafe { dealloc(self.buf, Layout::from_size_align(self.cap, 1).unwrap()) }
+ }
+}
+
+// Assert that the alignment of `Shared` is divisible by 2.
+// This is a necessary invariant since we depend on allocating `Shared` a
+// shared object to implicitly carry the `KIND_ARC` flag in its pointer.
+// This flag is set when the LSB is 0.
+const _: [(); 0 - mem::align_of::<Shared>() % 2] = []; // Assert that the alignment of `Shared` is divisible by 2.
+
+static SHARED_VTABLE: Vtable = Vtable {
+ clone: shared_clone,
+ to_vec: shared_to_vec,
+ drop: shared_drop,
+};
+
+const KIND_ARC: usize = 0b0;
+const KIND_VEC: usize = 0b1;
+const KIND_MASK: usize = 0b1;
+
+unsafe fn shared_clone(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Bytes {
+ let shared = data.load(Ordering::Relaxed);
+ shallow_clone_arc(shared as _, ptr, len)
+}
+
+unsafe fn shared_to_vec_impl(shared: *mut Shared, ptr: *const u8, len: usize) -> Vec<u8> {
+ // Check that the ref_cnt is 1 (unique).
+ //
+ // If it is unique, then it is set to 0 with AcqRel fence for the same
+ // reason in release_shared.
+ //
+ // Otherwise, we take the other branch and call release_shared.
+ if (*shared)
+ .ref_cnt
+ .compare_exchange(1, 0, Ordering::AcqRel, Ordering::Relaxed)
+ .is_ok()
+ {
+ let buf = (*shared).buf;
+ let cap = (*shared).cap;
+
+ // Deallocate Shared
+ drop(Box::from_raw(shared as *mut mem::ManuallyDrop<Shared>));
+
+ // 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<u8> {
+ shared_to_vec_impl(data.load(Ordering::Relaxed).cast(), ptr, len)
+}
+
+unsafe fn shared_drop(data: &mut AtomicPtr<()>, _ptr: *const u8, _len: usize) {
+ data.with_mut(|shared| {
+ release_shared(shared.cast());
+ });
+}
+
+unsafe fn shallow_clone_arc(shared: *mut Shared, ptr: *const u8, len: usize) -> Bytes {
+ let old_size = (*shared).ref_cnt.fetch_add(1, Ordering::Relaxed);
+
+ if old_size > usize::MAX >> 1 {
+ crate::abort();
+ }
+
+ Bytes {
+ ptr,
+ len,
+ data: AtomicPtr::new(shared as _),
+ vtable: &SHARED_VTABLE,
+ }
+}
+
+#[cold]
+unsafe fn shallow_clone_vec(
+ atom: &AtomicPtr<()>,
+ ptr: *const (),
+ buf: *mut u8,
+ offset: *const u8,
+ len: usize,
+) -> Bytes {
+ // If the buffer is still tracked in a `Vec<u8>`. It is time to
+ // promote the vec to an `Arc`. This could potentially be called
+ // concurrently, so some care must be taken.
+
+ // First, allocate a new `Shared` instance containing the
+ // `Vec` fields. It's important to note that `ptr`, `len`,
+ // and `cap` cannot be mutated without having `&mut self`.
+ // This means that these fields will not be concurrently
+ // updated and since the buffer hasn't been promoted to an
+ // `Arc`, those three fields still are the components of the
+ // vector.
+ let shared = Box::new(Shared {
+ buf,
+ cap: (offset as usize - buf as usize) + len,
+ // Initialize refcount to 2. One for this reference, and one
+ // for the new clone that will be returned from
+ // `shallow_clone`.
+ ref_cnt: AtomicUsize::new(2),
+ });
+
+ let shared = Box::into_raw(shared);
+
+ // The pointer should be aligned, so this assert should
+ // always succeed.
+ debug_assert!(
+ 0 == (shared as usize & KIND_MASK),
+ "internal: Box<Shared> 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<F>(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<F>(ptr: *mut u8, f: F) -> *mut u8
+where
+ F: FnOnce(usize) -> usize,
+{
+ let old_addr = ptr as usize;
+ let new_addr = f(old_addr);
+ new_addr as *mut u8
+}
+
+// compile-fails
+
+/// ```compile_fail
+/// use bytes::Bytes;
+/// #[deny(unused_must_use)]
+/// {
+/// let mut b1 = Bytes::from("hello world");
+/// b1.split_to(6);
+/// }
+/// ```
+fn _split_to_must_use() {}
+
+/// ```compile_fail
+/// use bytes::Bytes;
+/// #[deny(unused_must_use)]
+/// {
+/// let mut b1 = Bytes::from("hello world");
+/// b1.split_off(6);
+/// }
+/// ```
+fn _split_off_must_use() {}
+
+// fuzz tests
+#[cfg(all(test, loom))]
+mod fuzz {
+ use loom::sync::Arc;
+ use loom::thread;
+
+ use super::Bytes;
+ #[test]
+ fn bytes_cloning_vec() {
+ loom::model(|| {
+ let a = Bytes::from(b"abcdefgh".to_vec());
+ let addr = a.as_ptr() as usize;
+
+ // test the Bytes::clone is Sync by putting it in an Arc
+ let a1 = Arc::new(a);
+ let a2 = a1.clone();
+
+ let t1 = thread::spawn(move || {
+ let b: Bytes = (*a1).clone();
+ assert_eq!(b.as_ptr() as usize, addr);
+ });
+
+ let t2 = thread::spawn(move || {
+ let b: Bytes = (*a2).clone();
+ assert_eq!(b.as_ptr() as usize, addr);
+ });
+
+ t1.join().unwrap();
+ t2.join().unwrap();
+ });
+ }
+}
diff --git a/third_party/rust/bytes/src/bytes_mut.rs b/third_party/rust/bytes/src/bytes_mut.rs
new file mode 100644
index 0000000000..70613b2248
--- /dev/null
+++ b/third_party/rust/bytes/src/bytes_mut.rs
@@ -0,0 +1,1812 @@
+use core::iter::{FromIterator, Iterator};
+use core::mem::{self, ManuallyDrop, MaybeUninit};
+use core::ops::{Deref, DerefMut};
+use core::ptr::{self, NonNull};
+use core::{cmp, fmt, hash, isize, slice, usize};
+
+use alloc::{
+ borrow::{Borrow, BorrowMut},
+ boxed::Box,
+ string::String,
+ vec,
+ vec::Vec,
+};
+
+use crate::buf::{IntoIter, UninitSlice};
+use crate::bytes::Vtable;
+#[allow(unused)]
+use crate::loom::sync::atomic::AtomicMut;
+use crate::loom::sync::atomic::{AtomicPtr, AtomicUsize, Ordering};
+use crate::{Buf, BufMut, Bytes};
+
+/// A unique reference to a contiguous slice of memory.
+///
+/// `BytesMut` represents a unique view into a potentially shared memory region.
+/// Given the uniqueness guarantee, owners of `BytesMut` handles are able to
+/// mutate the memory.
+///
+/// `BytesMut` can be thought of as containing a `buf: Arc<Vec<u8>>`, 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<u8>,
+ 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<u8>,
+ original_capacity_repr: usize,
+ ref_count: AtomicUsize,
+}
+
+// Buffer storage strategy flags.
+const KIND_ARC: usize = 0b0;
+const KIND_VEC: usize = 0b1;
+const KIND_MASK: usize = 0b1;
+
+// The max original capacity value. Any `Bytes` allocated with a greater initial
+// capacity will default to this.
+const MAX_ORIGINAL_CAPACITY_WIDTH: usize = 17;
+// The original capacity algorithm will not take effect unless the originally
+// allocated capacity was at least 1kb in size.
+const MIN_ORIGINAL_CAPACITY_WIDTH: usize = 10;
+// The original capacity is stored in powers of 2 starting at 1kb to a max of
+// 64kb. Representing it as such requires only 3 bits of storage.
+const ORIGINAL_CAPACITY_MASK: usize = 0b11100;
+const ORIGINAL_CAPACITY_OFFSET: usize = 2;
+
+// When the storage is in the `Vec` representation, the pointer can be advanced
+// at most this value. This is due to the amount of storage available to track
+// the offset is usize - number of KIND bits and number of ORIGINAL_CAPACITY
+// bits.
+const VEC_POS_OFFSET: usize = 5;
+const MAX_VEC_POS: usize = usize::MAX >> VEC_POS_OFFSET;
+const NOT_VEC_POS_MASK: usize = 0b11111;
+
+#[cfg(target_pointer_width = "64")]
+const PTR_WIDTH: usize = 64;
+#[cfg(target_pointer_width = "32")]
+const PTR_WIDTH: usize = 32;
+
+/*
+ *
+ * ===== BytesMut =====
+ *
+ */
+
+impl BytesMut {
+ /// Creates a new `BytesMut` with the specified capacity.
+ ///
+ /// The returned `BytesMut` will be able to hold at least `capacity` bytes
+ /// without reallocating.
+ ///
+ /// It is important to note that this function does not specify the length
+ /// of the returned `BytesMut`, but only the capacity.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::{BytesMut, BufMut};
+ ///
+ /// let mut bytes = BytesMut::with_capacity(64);
+ ///
+ /// // `bytes` contains no data, even though there is capacity
+ /// assert_eq!(bytes.len(), 0);
+ ///
+ /// bytes.put(&b"hello world"[..]);
+ ///
+ /// assert_eq!(&bytes[..], b"hello world");
+ /// ```
+ #[inline]
+ pub fn with_capacity(capacity: usize) -> BytesMut {
+ BytesMut::from_vec(Vec::with_capacity(capacity))
+ }
+
+ /// Creates a new `BytesMut` with default capacity.
+ ///
+ /// Resulting object has length 0 and unspecified capacity.
+ /// This function does not allocate.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::{BytesMut, BufMut};
+ ///
+ /// let mut bytes = BytesMut::new();
+ ///
+ /// assert_eq!(0, bytes.len());
+ ///
+ /// bytes.reserve(2);
+ /// bytes.put_slice(b"xy");
+ ///
+ /// assert_eq!(&b"xy"[..], &bytes[..]);
+ /// ```
+ #[inline]
+ pub fn new() -> BytesMut {
+ BytesMut::with_capacity(0)
+ }
+
+ /// Returns the number of bytes contained in this `BytesMut`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BytesMut;
+ ///
+ /// let b = BytesMut::from(&b"hello"[..]);
+ /// assert_eq!(b.len(), 5);
+ /// ```
+ #[inline]
+ pub fn len(&self) -> usize {
+ self.len
+ }
+
+ /// Returns true if the `BytesMut` has a length of 0.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BytesMut;
+ ///
+ /// let b = BytesMut::with_capacity(64);
+ /// assert!(b.is_empty());
+ /// ```
+ #[inline]
+ pub fn is_empty(&self) -> bool {
+ self.len == 0
+ }
+
+ /// Returns the number of bytes the `BytesMut` can hold without reallocating.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BytesMut;
+ ///
+ /// let b = BytesMut::with_capacity(64);
+ /// assert_eq!(b.capacity(), 64);
+ /// ```
+ #[inline]
+ pub fn capacity(&self) -> usize {
+ self.cap
+ }
+
+ /// Converts `self` into an immutable `Bytes`.
+ ///
+ /// The conversion is zero cost and is used to indicate that the slice
+ /// referenced by the handle will no longer be mutated. Once the conversion
+ /// is done, the handle can be cloned and shared across threads.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::{BytesMut, BufMut};
+ /// use std::thread;
+ ///
+ /// let mut b = BytesMut::with_capacity(64);
+ /// b.put(&b"hello world"[..]);
+ /// let b1 = b.freeze();
+ /// let b2 = b1.clone();
+ ///
+ /// let th = thread::spawn(move || {
+ /// assert_eq!(&b1[..], b"hello world");
+ /// });
+ ///
+ /// assert_eq!(&b2[..], b"hello world");
+ /// th.join().unwrap();
+ /// ```
+ #[inline]
+ pub fn freeze(mut self) -> Bytes {
+ if self.kind() == KIND_VEC {
+ // Just re-use `Bytes` internal Vec vtable
+ unsafe {
+ let (off, _) = self.get_vec_pos();
+ let vec = rebuild_vec(self.ptr.as_ptr(), self.len, self.cap, off);
+ mem::forget(self);
+ let mut b: Bytes = vec.into();
+ b.advance(off);
+ b
+ }
+ } else {
+ debug_assert_eq!(self.kind(), KIND_ARC);
+
+ let ptr = self.ptr.as_ptr();
+ let len = self.len;
+ let data = AtomicPtr::new(self.data.cast());
+ mem::forget(self);
+ unsafe { Bytes::with_vtable(ptr, len, data, &SHARED_VTABLE) }
+ }
+ }
+
+ /// Creates a new `BytesMut`, which is initialized with zero.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BytesMut;
+ ///
+ /// let zeros = BytesMut::zeroed(42);
+ ///
+ /// assert_eq!(zeros.len(), 42);
+ /// zeros.into_iter().for_each(|x| assert_eq!(x, 0));
+ /// ```
+ pub fn zeroed(len: usize) -> BytesMut {
+ BytesMut::from_vec(vec![0; len])
+ }
+
+ /// Splits the bytes into two at the given index.
+ ///
+ /// Afterwards `self` contains elements `[0, at)`, and the returned
+ /// `BytesMut` contains elements `[at, capacity)`.
+ ///
+ /// This is an `O(1)` operation that just increases the reference count
+ /// and sets a few indices.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BytesMut;
+ ///
+ /// let mut a = BytesMut::from(&b"hello world"[..]);
+ /// let mut b = a.split_off(5);
+ ///
+ /// a[0] = b'j';
+ /// b[0] = b'!';
+ ///
+ /// assert_eq!(&a[..], b"jello");
+ /// assert_eq!(&b[..], b"!world");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// Panics if `at > capacity`.
+ #[must_use = "consider BytesMut::truncate if you don't need the other half"]
+ pub fn split_off(&mut self, at: usize) -> BytesMut {
+ assert!(
+ at <= self.capacity(),
+ "split_off out of bounds: {:?} <= {:?}",
+ at,
+ self.capacity(),
+ );
+ unsafe {
+ let mut other = self.shallow_clone();
+ other.set_start(at);
+ self.set_end(at);
+ other
+ }
+ }
+
+ /// Removes the bytes from the current view, returning them in a new
+ /// `BytesMut` handle.
+ ///
+ /// Afterwards, `self` will be empty, but will retain any additional
+ /// capacity that it had before the operation. This is identical to
+ /// `self.split_to(self.len())`.
+ ///
+ /// This is an `O(1)` operation that just increases the reference count and
+ /// sets a few indices.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::{BytesMut, BufMut};
+ ///
+ /// let mut buf = BytesMut::with_capacity(1024);
+ /// buf.put(&b"hello world"[..]);
+ ///
+ /// let other = buf.split();
+ ///
+ /// assert!(buf.is_empty());
+ /// assert_eq!(1013, buf.capacity());
+ ///
+ /// assert_eq!(other, b"hello world"[..]);
+ /// ```
+ #[must_use = "consider BytesMut::advance(len()) if you don't need the other half"]
+ pub fn split(&mut self) -> BytesMut {
+ let len = self.len();
+ self.split_to(len)
+ }
+
+ /// Splits the buffer into two at the given index.
+ ///
+ /// Afterwards `self` contains elements `[at, len)`, and the returned `BytesMut`
+ /// contains elements `[0, at)`.
+ ///
+ /// This is an `O(1)` operation that just increases the reference count and
+ /// sets a few indices.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BytesMut;
+ ///
+ /// let mut a = BytesMut::from(&b"hello world"[..]);
+ /// let mut b = a.split_to(5);
+ ///
+ /// a[0] = b'!';
+ /// b[0] = b'j';
+ ///
+ /// assert_eq!(&a[..], b"!world");
+ /// assert_eq!(&b[..], b"jello");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// Panics if `at > len`.
+ #[must_use = "consider BytesMut::advance if you don't need the other half"]
+ pub fn split_to(&mut self, at: usize) -> BytesMut {
+ assert!(
+ at <= self.len(),
+ "split_to out of bounds: {:?} <= {:?}",
+ at,
+ self.len(),
+ );
+
+ unsafe {
+ let mut other = self.shallow_clone();
+ other.set_end(at);
+ self.set_start(at);
+ other
+ }
+ }
+
+ /// Shortens the buffer, keeping the first `len` bytes and dropping the
+ /// rest.
+ ///
+ /// If `len` is greater than the buffer's current length, this has no
+ /// effect.
+ ///
+ /// Existing underlying capacity is preserved.
+ ///
+ /// The [`split_off`] method can emulate `truncate`, but this causes the
+ /// excess bytes to be returned instead of dropped.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BytesMut;
+ ///
+ /// let mut buf = BytesMut::from(&b"hello world"[..]);
+ /// buf.truncate(5);
+ /// assert_eq!(buf, b"hello"[..]);
+ /// ```
+ ///
+ /// [`split_off`]: #method.split_off
+ pub fn truncate(&mut self, len: usize) {
+ if len <= self.len() {
+ unsafe {
+ self.set_len(len);
+ }
+ }
+ }
+
+ /// Clears the buffer, removing all data. Existing capacity is preserved.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BytesMut;
+ ///
+ /// let mut buf = BytesMut::from(&b"hello world"[..]);
+ /// buf.clear();
+ /// assert!(buf.is_empty());
+ /// ```
+ pub fn clear(&mut self) {
+ self.truncate(0);
+ }
+
+ /// Resizes the buffer so that `len` is equal to `new_len`.
+ ///
+ /// If `new_len` is greater than `len`, the buffer is extended by the
+ /// difference with each additional byte set to `value`. If `new_len` is
+ /// less than `len`, the buffer is simply truncated.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BytesMut;
+ ///
+ /// let mut buf = BytesMut::new();
+ ///
+ /// buf.resize(3, 0x1);
+ /// assert_eq!(&buf[..], &[0x1, 0x1, 0x1]);
+ ///
+ /// buf.resize(2, 0x2);
+ /// assert_eq!(&buf[..], &[0x1, 0x1]);
+ ///
+ /// buf.resize(4, 0x3);
+ /// assert_eq!(&buf[..], &[0x1, 0x1, 0x3, 0x3]);
+ /// ```
+ pub fn resize(&mut self, new_len: usize, value: u8) {
+ let len = self.len();
+ if new_len > len {
+ let additional = new_len - len;
+ self.reserve(additional);
+ unsafe {
+ let dst = self.chunk_mut().as_mut_ptr();
+ ptr::write_bytes(dst, value, additional);
+ self.set_len(new_len);
+ }
+ } else {
+ self.truncate(new_len);
+ }
+ }
+
+ /// Sets the length of the buffer.
+ ///
+ /// This will explicitly set the size of the buffer without actually
+ /// modifying the data, so it is up to the caller to ensure that the data
+ /// has been initialized.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BytesMut;
+ ///
+ /// let mut b = BytesMut::from(&b"hello world"[..]);
+ ///
+ /// unsafe {
+ /// b.set_len(5);
+ /// }
+ ///
+ /// assert_eq!(&b[..], b"hello");
+ ///
+ /// unsafe {
+ /// b.set_len(11);
+ /// }
+ ///
+ /// assert_eq!(&b[..], b"hello world");
+ /// ```
+ #[inline]
+ pub unsafe fn set_len(&mut self, len: usize) {
+ debug_assert!(len <= self.cap, "set_len out of bounds");
+ self.len = len;
+ }
+
+ /// Reserves capacity for at least `additional` more bytes to be inserted
+ /// into the given `BytesMut`.
+ ///
+ /// More than `additional` bytes may be reserved in order to avoid frequent
+ /// reallocations. A call to `reserve` may result in an allocation.
+ ///
+ /// Before allocating new buffer space, the function will attempt to reclaim
+ /// space in the existing buffer. If the current handle references a view
+ /// into a larger original buffer, and all other handles referencing part
+ /// of the same original buffer have been dropped, then the current view
+ /// can be copied/shifted to the front of the buffer and the handle can take
+ /// ownership of the full buffer, provided that the full buffer is large
+ /// enough to fit the requested additional capacity.
+ ///
+ /// This optimization will only happen if shifting the data from the current
+ /// view to the front of the buffer is not too expensive in terms of the
+ /// (amortized) time required. The precise condition is subject to change;
+ /// as of now, the length of the data being shifted needs to be at least as
+ /// large as the distance that it's shifted by. If the current view is empty
+ /// and the original buffer is large enough to fit the requested additional
+ /// capacity, then reallocations will never happen.
+ ///
+ /// # Examples
+ ///
+ /// In the following example, a new buffer is allocated.
+ ///
+ /// ```
+ /// use bytes::BytesMut;
+ ///
+ /// let mut buf = BytesMut::from(&b"hello"[..]);
+ /// buf.reserve(64);
+ /// assert!(buf.capacity() >= 69);
+ /// ```
+ ///
+ /// In the following example, the existing buffer is reclaimed.
+ ///
+ /// ```
+ /// use bytes::{BytesMut, BufMut};
+ ///
+ /// let mut buf = BytesMut::with_capacity(128);
+ /// buf.put(&[0; 64][..]);
+ ///
+ /// let ptr = buf.as_ptr();
+ /// let other = buf.split();
+ ///
+ /// assert!(buf.is_empty());
+ /// assert_eq!(buf.capacity(), 64);
+ ///
+ /// drop(other);
+ /// buf.reserve(128);
+ ///
+ /// assert_eq!(buf.capacity(), 128);
+ /// assert_eq!(buf.as_ptr(), ptr);
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// Panics if the new capacity overflows `usize`.
+ #[inline]
+ pub fn reserve(&mut self, additional: usize) {
+ let len = self.len();
+ let rem = self.capacity() - len;
+
+ if additional <= rem {
+ // The handle can already store at least `additional` more bytes, so
+ // there is no further work needed to be done.
+ return;
+ }
+
+ self.reserve_inner(additional);
+ }
+
+ // In separate function to allow the short-circuits in `reserve` to
+ // be inline-able. Significant helps performance.
+ fn reserve_inner(&mut self, additional: usize) {
+ let len = self.len();
+ let kind = self.kind();
+
+ if kind == KIND_VEC {
+ // If there's enough free space before the start of the buffer, then
+ // just copy the data backwards and reuse the already-allocated
+ // space.
+ //
+ // Otherwise, since backed by a vector, use `Vec::reserve`
+ //
+ // We need to make sure that this optimization does not kill the
+ // amortized runtimes of BytesMut's operations.
+ unsafe {
+ let (off, prev) = self.get_vec_pos();
+
+ // Only reuse space if we can satisfy the requested additional space.
+ //
+ // Also check if the value of `off` suggests that enough bytes
+ // have been read to account for the overhead of shifting all
+ // the data (in an amortized analysis).
+ // Hence the condition `off >= self.len()`.
+ //
+ // This condition also already implies that the buffer is going
+ // to be (at least) half-empty in the end; so we do not break
+ // the (amortized) runtime with future resizes of the underlying
+ // `Vec`.
+ //
+ // [For more details check issue #524, and PR #525.]
+ if self.capacity() - self.len() + off >= additional && off >= self.len() {
+ // There's enough space, and it's not too much overhead:
+ // reuse the space!
+ //
+ // Just move the pointer back to the start after copying
+ // data back.
+ let base_ptr = self.ptr.as_ptr().offset(-(off as isize));
+ // Since `off >= self.len()`, the two regions don't overlap.
+ ptr::copy_nonoverlapping(self.ptr.as_ptr(), base_ptr, self.len);
+ self.ptr = vptr(base_ptr);
+ self.set_vec_pos(0, prev);
+
+ // Length stays constant, but since we moved backwards we
+ // can gain capacity back.
+ self.cap += off;
+ } else {
+ // Not enough space, or reusing might be too much overhead:
+ // allocate more space!
+ let mut v =
+ ManuallyDrop::new(rebuild_vec(self.ptr.as_ptr(), self.len, self.cap, off));
+ v.reserve(additional);
+
+ // Update the info
+ self.ptr = vptr(v.as_mut_ptr().add(off));
+ self.len = v.len() - off;
+ self.cap = v.capacity() - off;
+ }
+
+ return;
+ }
+ }
+
+ debug_assert_eq!(kind, KIND_ARC);
+ let shared: *mut Shared = self.data;
+
+ // Reserving involves abandoning the currently shared buffer and
+ // allocating a new vector with the requested capacity.
+ //
+ // Compute the new capacity
+ let mut new_cap = len.checked_add(additional).expect("overflow");
+
+ let original_capacity;
+ let original_capacity_repr;
+
+ unsafe {
+ original_capacity_repr = (*shared).original_capacity_repr;
+ original_capacity = original_capacity_from_repr(original_capacity_repr);
+
+ // First, try to reclaim the buffer. This is possible if the current
+ // handle is the only outstanding handle pointing to the buffer.
+ if (*shared).is_unique() {
+ // This is the only handle to the buffer. It can be reclaimed.
+ // However, before doing the work of copying data, check to make
+ // sure that the vector has enough capacity.
+ let v = &mut (*shared).vec;
+
+ let v_capacity = v.capacity();
+ let ptr = v.as_mut_ptr();
+
+ let offset = offset_from(self.ptr.as_ptr(), ptr);
+
+ // Compare the condition in the `kind == KIND_VEC` case above
+ // for more details.
+ if v_capacity >= new_cap + offset {
+ self.cap = new_cap;
+ // no copy is necessary
+ } else if v_capacity >= new_cap && offset >= len {
+ // The capacity is sufficient, and copying is not too much
+ // overhead: reclaim the buffer!
+
+ // `offset >= len` means: no overlap
+ ptr::copy_nonoverlapping(self.ptr.as_ptr(), ptr, len);
+
+ self.ptr = vptr(ptr);
+ self.cap = v.capacity();
+ } else {
+ // calculate offset
+ let off = (self.ptr.as_ptr() as usize) - (v.as_ptr() as usize);
+
+ // new_cap is calculated in terms of `BytesMut`, not the underlying
+ // `Vec`, so it does not take the offset into account.
+ //
+ // Thus we have to manually add it here.
+ new_cap = new_cap.checked_add(off).expect("overflow");
+
+ // The vector capacity is not sufficient. The reserve request is
+ // asking for more than the initial buffer capacity. Allocate more
+ // than requested if `new_cap` is not much bigger than the current
+ // capacity.
+ //
+ // There are some situations, using `reserve_exact` that the
+ // buffer capacity could be below `original_capacity`, so do a
+ // check.
+ let double = v.capacity().checked_shl(1).unwrap_or(new_cap);
+
+ new_cap = cmp::max(double, new_cap);
+
+ // No space - allocate more
+ //
+ // The length field of `Shared::vec` is not used by the `BytesMut`;
+ // instead we use the `len` field in the `BytesMut` itself. However,
+ // when calling `reserve`, it doesn't guarantee that data stored in
+ // the unused capacity of the vector is copied over to the new
+ // allocation, so we need to ensure that we don't have any data we
+ // care about in the unused capacity before calling `reserve`.
+ debug_assert!(off + len <= v.capacity());
+ v.set_len(off + len);
+ v.reserve(new_cap - v.len());
+
+ // Update the info
+ self.ptr = vptr(v.as_mut_ptr().add(off));
+ self.cap = v.capacity() - off;
+ }
+
+ return;
+ } else {
+ new_cap = cmp::max(new_cap, original_capacity);
+ }
+ }
+
+ // Create a new vector to store the data
+ let mut v = ManuallyDrop::new(Vec::with_capacity(new_cap));
+
+ // Copy the bytes
+ v.extend_from_slice(self.as_ref());
+
+ // Release the shared handle. This must be done *after* the bytes are
+ // copied.
+ unsafe { release_shared(shared) };
+
+ // Update self
+ let data = (original_capacity_repr << ORIGINAL_CAPACITY_OFFSET) | KIND_VEC;
+ self.data = invalid_ptr(data);
+ self.ptr = vptr(v.as_mut_ptr());
+ self.len = v.len();
+ self.cap = v.capacity();
+ }
+
+ /// Appends given bytes to this `BytesMut`.
+ ///
+ /// If this `BytesMut` object does not have enough capacity, it is resized
+ /// first.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BytesMut;
+ ///
+ /// let mut buf = BytesMut::with_capacity(0);
+ /// buf.extend_from_slice(b"aaabbb");
+ /// buf.extend_from_slice(b"cccddd");
+ ///
+ /// assert_eq!(b"aaabbbcccddd", &buf[..]);
+ /// ```
+ pub fn extend_from_slice(&mut self, extend: &[u8]) {
+ let cnt = extend.len();
+ self.reserve(cnt);
+
+ unsafe {
+ let dst = self.spare_capacity_mut();
+ // Reserved above
+ debug_assert!(dst.len() >= cnt);
+
+ ptr::copy_nonoverlapping(extend.as_ptr(), dst.as_mut_ptr().cast(), cnt);
+ }
+
+ unsafe {
+ self.advance_mut(cnt);
+ }
+ }
+
+ /// Absorbs a `BytesMut` that was previously split off.
+ ///
+ /// If the two `BytesMut` objects were previously contiguous and not mutated
+ /// in a way that causes re-allocation i.e., if `other` was created by
+ /// calling `split_off` on this `BytesMut`, then this is an `O(1)` operation
+ /// that just decreases a reference count and sets a few indices.
+ /// Otherwise this method degenerates to
+ /// `self.extend_from_slice(other.as_ref())`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BytesMut;
+ ///
+ /// let mut buf = BytesMut::with_capacity(64);
+ /// buf.extend_from_slice(b"aaabbbcccddd");
+ ///
+ /// let split = buf.split_off(6);
+ /// assert_eq!(b"aaabbb", &buf[..]);
+ /// assert_eq!(b"cccddd", &split[..]);
+ ///
+ /// buf.unsplit(split);
+ /// assert_eq!(b"aaabbbcccddd", &buf[..]);
+ /// ```
+ pub fn unsplit(&mut self, other: BytesMut) {
+ if self.is_empty() {
+ *self = other;
+ return;
+ }
+
+ if let Err(other) = self.try_unsplit(other) {
+ self.extend_from_slice(other.as_ref());
+ }
+ }
+
+ // private
+
+ // For now, use a `Vec` to manage the memory for us, but we may want to
+ // change that in the future to some alternate allocator strategy.
+ //
+ // Thus, we don't expose an easy way to construct from a `Vec` since an
+ // internal change could make a simple pattern (`BytesMut::from(vec)`)
+ // suddenly a lot more expensive.
+ #[inline]
+ pub(crate) fn from_vec(mut vec: Vec<u8>) -> BytesMut {
+ let ptr = vptr(vec.as_mut_ptr());
+ let len = vec.len();
+ let cap = vec.capacity();
+ mem::forget(vec);
+
+ let original_capacity_repr = original_capacity_to_repr(cap);
+ let data = (original_capacity_repr << ORIGINAL_CAPACITY_OFFSET) | KIND_VEC;
+
+ BytesMut {
+ ptr,
+ len,
+ cap,
+ data: invalid_ptr(data),
+ }
+ }
+
+ #[inline]
+ fn as_slice(&self) -> &[u8] {
+ unsafe { slice::from_raw_parts(self.ptr.as_ptr(), self.len) }
+ }
+
+ #[inline]
+ fn as_slice_mut(&mut self) -> &mut [u8] {
+ unsafe { slice::from_raw_parts_mut(self.ptr.as_ptr(), self.len) }
+ }
+
+ unsafe fn set_start(&mut self, start: usize) {
+ // Setting the start to 0 is a no-op, so return early if this is the
+ // case.
+ if start == 0 {
+ return;
+ }
+
+ debug_assert!(start <= self.cap, "internal: set_start out of bounds");
+
+ let kind = self.kind();
+
+ if kind == KIND_VEC {
+ // Setting the start when in vec representation is a little more
+ // complicated. First, we have to track how far ahead the
+ // "start" of the byte buffer from the beginning of the vec. We
+ // also have to ensure that we don't exceed the maximum shift.
+ let (mut pos, prev) = self.get_vec_pos();
+ pos += start;
+
+ if pos <= MAX_VEC_POS {
+ self.set_vec_pos(pos, prev);
+ } else {
+ // The repr must be upgraded to ARC. This will never happen
+ // on 64 bit systems and will only happen on 32 bit systems
+ // when shifting past 134,217,727 bytes. As such, we don't
+ // worry too much about performance here.
+ self.promote_to_shared(/*ref_count = */ 1);
+ }
+ }
+
+ // Updating the start of the view is setting `ptr` to point to the
+ // new start and updating the `len` field to reflect the new length
+ // of the view.
+ self.ptr = vptr(self.ptr.as_ptr().add(start));
+
+ if self.len >= start {
+ self.len -= start;
+ } else {
+ self.len = 0;
+ }
+
+ self.cap -= start;
+ }
+
+ unsafe fn set_end(&mut self, end: usize) {
+ debug_assert_eq!(self.kind(), KIND_ARC);
+ assert!(end <= self.cap, "set_end out of bounds");
+
+ self.cap = end;
+ self.len = cmp::min(self.len, end);
+ }
+
+ fn try_unsplit(&mut self, other: BytesMut) -> Result<(), BytesMut> {
+ if other.capacity() == 0 {
+ return Ok(());
+ }
+
+ let ptr = unsafe { self.ptr.as_ptr().add(self.len) };
+ if ptr == other.ptr.as_ptr()
+ && self.kind() == KIND_ARC
+ && other.kind() == KIND_ARC
+ && self.data == other.data
+ {
+ // Contiguous blocks, just combine directly
+ self.len += other.len;
+ self.cap += other.cap;
+ Ok(())
+ } else {
+ Err(other)
+ }
+ }
+
+ #[inline]
+ fn kind(&self) -> usize {
+ self.data as usize & KIND_MASK
+ }
+
+ unsafe fn promote_to_shared(&mut self, ref_cnt: usize) {
+ debug_assert_eq!(self.kind(), KIND_VEC);
+ debug_assert!(ref_cnt == 1 || ref_cnt == 2);
+
+ let original_capacity_repr =
+ (self.data as usize & ORIGINAL_CAPACITY_MASK) >> ORIGINAL_CAPACITY_OFFSET;
+
+ // The vec offset cannot be concurrently mutated, so there
+ // should be no danger reading it.
+ let off = (self.data as usize) >> VEC_POS_OFFSET;
+
+ // First, allocate a new `Shared` instance containing the
+ // `Vec` fields. It's important to note that `ptr`, `len`,
+ // and `cap` cannot be mutated without having `&mut self`.
+ // This means that these fields will not be concurrently
+ // updated and since the buffer hasn't been promoted to an
+ // `Arc`, those three fields still are the components of the
+ // vector.
+ let shared = Box::new(Shared {
+ vec: rebuild_vec(self.ptr.as_ptr(), self.len, self.cap, off),
+ original_capacity_repr,
+ ref_count: AtomicUsize::new(ref_cnt),
+ });
+
+ let shared = Box::into_raw(shared);
+
+ // The pointer should be aligned, so this assert should
+ // always succeed.
+ debug_assert_eq!(shared as usize & KIND_MASK, KIND_ARC);
+
+ self.data = shared;
+ }
+
+ /// Makes an exact shallow clone of `self`.
+ ///
+ /// The kind of `self` doesn't matter, but this is unsafe
+ /// because the clone will have the same offsets. You must
+ /// be sure the returned value to the user doesn't allow
+ /// two views into the same range.
+ #[inline]
+ unsafe fn shallow_clone(&mut self) -> BytesMut {
+ if self.kind() == KIND_ARC {
+ increment_shared(self.data);
+ ptr::read(self)
+ } else {
+ self.promote_to_shared(/*ref_count = */ 2);
+ ptr::read(self)
+ }
+ }
+
+ #[inline]
+ unsafe fn get_vec_pos(&mut self) -> (usize, usize) {
+ debug_assert_eq!(self.kind(), KIND_VEC);
+
+ let prev = self.data as usize;
+ (prev >> VEC_POS_OFFSET, prev)
+ }
+
+ #[inline]
+ unsafe fn set_vec_pos(&mut self, pos: usize, prev: usize) {
+ debug_assert_eq!(self.kind(), KIND_VEC);
+ debug_assert!(pos <= MAX_VEC_POS);
+
+ self.data = invalid_ptr((pos << VEC_POS_OFFSET) | (prev & NOT_VEC_POS_MASK));
+ }
+
+ /// Returns the remaining spare capacity of the buffer as a slice of `MaybeUninit<u8>`.
+ ///
+ /// 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<u8>] {
+ unsafe {
+ let ptr = self.ptr.as_ptr().add(self.len);
+ let len = self.cap - self.len;
+
+ slice::from_raw_parts_mut(ptr.cast(), len)
+ }
+ }
+}
+
+impl Drop for BytesMut {
+ fn drop(&mut self) {
+ let kind = self.kind();
+
+ if kind == KIND_VEC {
+ unsafe {
+ let (off, _) = self.get_vec_pos();
+
+ // Vector storage, free the vector
+ let _ = rebuild_vec(self.ptr.as_ptr(), self.len, self.cap, off);
+ }
+ } else if kind == KIND_ARC {
+ unsafe { release_shared(self.data) };
+ }
+ }
+}
+
+impl Buf for BytesMut {
+ #[inline]
+ fn remaining(&self) -> usize {
+ self.len()
+ }
+
+ #[inline]
+ fn chunk(&self) -> &[u8] {
+ self.as_slice()
+ }
+
+ #[inline]
+ fn advance(&mut self, cnt: usize) {
+ assert!(
+ cnt <= self.remaining(),
+ "cannot advance past `remaining`: {:?} <= {:?}",
+ cnt,
+ self.remaining(),
+ );
+ unsafe {
+ self.set_start(cnt);
+ }
+ }
+
+ fn copy_to_bytes(&mut self, len: usize) -> crate::Bytes {
+ self.split_to(len).freeze()
+ }
+}
+
+unsafe impl BufMut for BytesMut {
+ #[inline]
+ fn remaining_mut(&self) -> usize {
+ usize::MAX - self.len()
+ }
+
+ #[inline]
+ unsafe fn advance_mut(&mut self, cnt: usize) {
+ let new_len = self.len() + cnt;
+ assert!(
+ new_len <= self.cap,
+ "new_len = {}; capacity = {}",
+ new_len,
+ self.cap
+ );
+ self.len = new_len;
+ }
+
+ #[inline]
+ fn chunk_mut(&mut self) -> &mut UninitSlice {
+ if self.capacity() == self.len() {
+ self.reserve(64);
+ }
+ UninitSlice::from_slice(self.spare_capacity_mut())
+ }
+
+ // Specialize these methods so they can skip checking `remaining_mut`
+ // and `advance_mut`.
+
+ fn put<T: crate::Buf>(&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<BytesMut> 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<cmp::Ordering> {
+ 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<H>(&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<BytesMut>;
+
+ 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<u8> for BytesMut {
+ fn extend<T>(&mut self, iter: T)
+ where
+ T: IntoIterator<Item = u8>,
+ {
+ let iter = iter.into_iter();
+
+ let (lower, _) = iter.size_hint();
+ self.reserve(lower);
+
+ // TODO: optimize
+ // 1. If self.kind() == KIND_VEC, use Vec::extend
+ // 2. Make `reserve` inline-able
+ for b in iter {
+ self.reserve(1);
+ self.put_u8(b);
+ }
+ }
+}
+
+impl<'a> Extend<&'a u8> for BytesMut {
+ fn extend<T>(&mut self, iter: T)
+ where
+ T: IntoIterator<Item = &'a u8>,
+ {
+ self.extend(iter.into_iter().copied())
+ }
+}
+
+impl Extend<Bytes> for BytesMut {
+ fn extend<T>(&mut self, iter: T)
+ where
+ T: IntoIterator<Item = Bytes>,
+ {
+ for bytes in iter {
+ self.extend_from_slice(&bytes)
+ }
+ }
+}
+
+impl FromIterator<u8> for BytesMut {
+ fn from_iter<T: IntoIterator<Item = u8>>(into_iter: T) -> Self {
+ BytesMut::from_vec(Vec::from_iter(into_iter))
+ }
+}
+
+impl<'a> FromIterator<&'a u8> for BytesMut {
+ fn from_iter<T: IntoIterator<Item = &'a u8>>(into_iter: T) -> Self {
+ BytesMut::from_iter(into_iter.into_iter().copied())
+ }
+}
+
+/*
+ *
+ * ===== Inner =====
+ *
+ */
+
+unsafe fn increment_shared(ptr: *mut Shared) {
+ let old_size = (*ptr).ref_count.fetch_add(1, Ordering::Relaxed);
+
+ if old_size > isize::MAX as usize {
+ crate::abort();
+ }
+}
+
+unsafe fn release_shared(ptr: *mut Shared) {
+ // `Shared` storage... follow the drop steps from Arc.
+ if (*ptr).ref_count.fetch_sub(1, Ordering::Release) != 1 {
+ return;
+ }
+
+ // This fence is needed to prevent reordering of use of the data and
+ // deletion of the data. Because it is marked `Release`, the decreasing
+ // of the reference count synchronizes with this `Acquire` fence. This
+ // means that use of the data happens before decreasing the reference
+ // count, which happens before this fence, which happens before the
+ // deletion of the data.
+ //
+ // As explained in the [Boost documentation][1],
+ //
+ // > It is important to enforce any possible access to the object in one
+ // > thread (through an existing reference) to *happen before* deleting
+ // > the object in a different thread. This is achieved by a "release"
+ // > operation after dropping a reference (any access to the object
+ // > through this reference must obviously happened before), and an
+ // > "acquire" operation before deleting the object.
+ //
+ // [1]: (www.boost.org/doc/libs/1_55_0/doc/html/atomic/usage_examples.html)
+ //
+ // Thread sanitizer does not support atomic fences. Use an atomic load
+ // instead.
+ (*ptr).ref_count.load(Ordering::Acquire);
+
+ // Drop the data
+ drop(Box::from_raw(ptr));
+}
+
+impl Shared {
+ fn is_unique(&self) -> bool {
+ // The goal is to check if the current handle is the only handle
+ // that currently has access to the buffer. This is done by
+ // checking if the `ref_count` is currently 1.
+ //
+ // The `Acquire` ordering synchronizes with the `Release` as
+ // part of the `fetch_sub` in `release_shared`. The `fetch_sub`
+ // operation guarantees that any mutations done in other threads
+ // are ordered before the `ref_count` is decremented. As such,
+ // this `Acquire` will guarantee that those mutations are
+ // visible to the current thread.
+ self.ref_count.load(Ordering::Acquire) == 1
+ }
+}
+
+#[inline]
+fn original_capacity_to_repr(cap: usize) -> usize {
+ let width = PTR_WIDTH - ((cap >> MIN_ORIGINAL_CAPACITY_WIDTH).leading_zeros() as usize);
+ cmp::min(
+ width,
+ MAX_ORIGINAL_CAPACITY_WIDTH - MIN_ORIGINAL_CAPACITY_WIDTH,
+ )
+}
+
+fn original_capacity_from_repr(repr: usize) -> usize {
+ if repr == 0 {
+ return 0;
+ }
+
+ 1 << (repr + (MIN_ORIGINAL_CAPACITY_WIDTH - 1))
+}
+
+/*
+#[test]
+fn test_original_capacity_to_repr() {
+ assert_eq!(original_capacity_to_repr(0), 0);
+
+ let max_width = 32;
+
+ for width in 1..(max_width + 1) {
+ let cap = 1 << width - 1;
+
+ let expected = if width < MIN_ORIGINAL_CAPACITY_WIDTH {
+ 0
+ } else if width < MAX_ORIGINAL_CAPACITY_WIDTH {
+ width - MIN_ORIGINAL_CAPACITY_WIDTH
+ } else {
+ MAX_ORIGINAL_CAPACITY_WIDTH - MIN_ORIGINAL_CAPACITY_WIDTH
+ };
+
+ assert_eq!(original_capacity_to_repr(cap), expected);
+
+ if width > 1 {
+ assert_eq!(original_capacity_to_repr(cap + 1), expected);
+ }
+
+ // MIN_ORIGINAL_CAPACITY_WIDTH must be bigger than 7 to pass tests below
+ if width == MIN_ORIGINAL_CAPACITY_WIDTH + 1 {
+ assert_eq!(original_capacity_to_repr(cap - 24), expected - 1);
+ assert_eq!(original_capacity_to_repr(cap + 76), expected);
+ } else if width == MIN_ORIGINAL_CAPACITY_WIDTH + 2 {
+ assert_eq!(original_capacity_to_repr(cap - 1), expected - 1);
+ assert_eq!(original_capacity_to_repr(cap - 48), expected - 1);
+ }
+ }
+}
+
+#[test]
+fn test_original_capacity_from_repr() {
+ assert_eq!(0, original_capacity_from_repr(0));
+
+ let min_cap = 1 << MIN_ORIGINAL_CAPACITY_WIDTH;
+
+ assert_eq!(min_cap, original_capacity_from_repr(1));
+ assert_eq!(min_cap * 2, original_capacity_from_repr(2));
+ assert_eq!(min_cap * 4, original_capacity_from_repr(3));
+ assert_eq!(min_cap * 8, original_capacity_from_repr(4));
+ assert_eq!(min_cap * 16, original_capacity_from_repr(5));
+ assert_eq!(min_cap * 32, original_capacity_from_repr(6));
+ assert_eq!(min_cap * 64, original_capacity_from_repr(7));
+}
+*/
+
+unsafe impl Send for BytesMut {}
+unsafe impl Sync for BytesMut {}
+
+/*
+ *
+ * ===== PartialEq / PartialOrd =====
+ *
+ */
+
+impl PartialEq<[u8]> for BytesMut {
+ fn eq(&self, other: &[u8]) -> bool {
+ &**self == other
+ }
+}
+
+impl PartialOrd<[u8]> for BytesMut {
+ fn partial_cmp(&self, other: &[u8]) -> Option<cmp::Ordering> {
+ (**self).partial_cmp(other)
+ }
+}
+
+impl PartialEq<BytesMut> for [u8] {
+ fn eq(&self, other: &BytesMut) -> bool {
+ *other == *self
+ }
+}
+
+impl PartialOrd<BytesMut> for [u8] {
+ fn partial_cmp(&self, other: &BytesMut) -> Option<cmp::Ordering> {
+ <[u8] as PartialOrd<[u8]>>::partial_cmp(self, other)
+ }
+}
+
+impl PartialEq<str> for BytesMut {
+ fn eq(&self, other: &str) -> bool {
+ &**self == other.as_bytes()
+ }
+}
+
+impl PartialOrd<str> for BytesMut {
+ fn partial_cmp(&self, other: &str) -> Option<cmp::Ordering> {
+ (**self).partial_cmp(other.as_bytes())
+ }
+}
+
+impl PartialEq<BytesMut> for str {
+ fn eq(&self, other: &BytesMut) -> bool {
+ *other == *self
+ }
+}
+
+impl PartialOrd<BytesMut> for str {
+ fn partial_cmp(&self, other: &BytesMut) -> Option<cmp::Ordering> {
+ <[u8] as PartialOrd<[u8]>>::partial_cmp(self.as_bytes(), other)
+ }
+}
+
+impl PartialEq<Vec<u8>> for BytesMut {
+ fn eq(&self, other: &Vec<u8>) -> bool {
+ *self == other[..]
+ }
+}
+
+impl PartialOrd<Vec<u8>> for BytesMut {
+ fn partial_cmp(&self, other: &Vec<u8>) -> Option<cmp::Ordering> {
+ (**self).partial_cmp(&other[..])
+ }
+}
+
+impl PartialEq<BytesMut> for Vec<u8> {
+ fn eq(&self, other: &BytesMut) -> bool {
+ *other == *self
+ }
+}
+
+impl PartialOrd<BytesMut> for Vec<u8> {
+ fn partial_cmp(&self, other: &BytesMut) -> Option<cmp::Ordering> {
+ other.partial_cmp(self)
+ }
+}
+
+impl PartialEq<String> for BytesMut {
+ fn eq(&self, other: &String) -> bool {
+ *self == other[..]
+ }
+}
+
+impl PartialOrd<String> for BytesMut {
+ fn partial_cmp(&self, other: &String) -> Option<cmp::Ordering> {
+ (**self).partial_cmp(other.as_bytes())
+ }
+}
+
+impl PartialEq<BytesMut> for String {
+ fn eq(&self, other: &BytesMut) -> bool {
+ *other == *self
+ }
+}
+
+impl PartialOrd<BytesMut> for String {
+ fn partial_cmp(&self, other: &BytesMut) -> Option<cmp::Ordering> {
+ <[u8] as PartialOrd<[u8]>>::partial_cmp(self.as_bytes(), other)
+ }
+}
+
+impl<'a, T: ?Sized> PartialEq<&'a T> for BytesMut
+where
+ BytesMut: PartialEq<T>,
+{
+ fn eq(&self, other: &&'a T) -> bool {
+ *self == **other
+ }
+}
+
+impl<'a, T: ?Sized> PartialOrd<&'a T> for BytesMut
+where
+ BytesMut: PartialOrd<T>,
+{
+ fn partial_cmp(&self, other: &&'a T) -> Option<cmp::Ordering> {
+ self.partial_cmp(*other)
+ }
+}
+
+impl PartialEq<BytesMut> for &[u8] {
+ fn eq(&self, other: &BytesMut) -> bool {
+ *other == *self
+ }
+}
+
+impl PartialOrd<BytesMut> for &[u8] {
+ fn partial_cmp(&self, other: &BytesMut) -> Option<cmp::Ordering> {
+ <[u8] as PartialOrd<[u8]>>::partial_cmp(self, other)
+ }
+}
+
+impl PartialEq<BytesMut> for &str {
+ fn eq(&self, other: &BytesMut) -> bool {
+ *other == *self
+ }
+}
+
+impl PartialOrd<BytesMut> for &str {
+ fn partial_cmp(&self, other: &BytesMut) -> Option<cmp::Ordering> {
+ other.partial_cmp(self)
+ }
+}
+
+impl PartialEq<BytesMut> for Bytes {
+ fn eq(&self, other: &BytesMut) -> bool {
+ other[..] == self[..]
+ }
+}
+
+impl PartialEq<Bytes> for BytesMut {
+ fn eq(&self, other: &Bytes) -> bool {
+ other[..] == self[..]
+ }
+}
+
+impl From<BytesMut> for Vec<u8> {
+ fn from(mut bytes: BytesMut) -> Self {
+ let kind = bytes.kind();
+
+ let mut vec = if kind == KIND_VEC {
+ unsafe {
+ let (off, _) = bytes.get_vec_pos();
+ rebuild_vec(bytes.ptr.as_ptr(), bytes.len, bytes.cap, off)
+ }
+ } else if kind == KIND_ARC {
+ let shared = bytes.data as *mut Shared;
+
+ if unsafe { (*shared).is_unique() } {
+ let vec = mem::replace(unsafe { &mut (*shared).vec }, Vec::new());
+
+ unsafe { release_shared(shared) };
+
+ vec
+ } else {
+ return bytes.deref().to_vec();
+ }
+ } else {
+ return bytes.deref().to_vec();
+ };
+
+ let len = bytes.len;
+
+ unsafe {
+ ptr::copy(bytes.ptr.as_ptr(), vec.as_mut_ptr(), len);
+ vec.set_len(len);
+ }
+
+ mem::forget(bytes);
+
+ vec
+ }
+}
+
+#[inline]
+fn vptr(ptr: *mut u8) -> NonNull<u8> {
+ 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<T>(addr: usize) -> *mut T {
+ let ptr = core::ptr::null_mut::<u8>().wrapping_add(addr);
+ debug_assert_eq!(ptr as usize, addr);
+ ptr.cast::<T>()
+}
+
+/// Precondition: dst >= original
+///
+/// The following line is equivalent to:
+///
+/// ```rust,ignore
+/// self.ptr.as_ptr().offset_from(ptr) as usize;
+/// ```
+///
+/// But due to min rust is 1.39 and it is only stablised
+/// in 1.47, we cannot use it.
+#[inline]
+fn offset_from(dst: *mut u8, original: *mut u8) -> usize {
+ debug_assert!(dst >= original);
+
+ dst as usize - original as usize
+}
+
+unsafe fn rebuild_vec(ptr: *mut u8, mut len: usize, mut cap: usize, off: usize) -> Vec<u8> {
+ let ptr = ptr.offset(-(off as isize));
+ len += off;
+ cap += off;
+
+ Vec::from_raw_parts(ptr, len, cap)
+}
+
+// ===== impl SharedVtable =====
+
+static SHARED_VTABLE: Vtable = Vtable {
+ clone: shared_v_clone,
+ to_vec: shared_v_to_vec,
+ drop: shared_v_drop,
+};
+
+unsafe fn shared_v_clone(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Bytes {
+ let shared = data.load(Ordering::Relaxed) as *mut Shared;
+ increment_shared(shared);
+
+ let data = AtomicPtr::new(shared as *mut ());
+ Bytes::with_vtable(ptr, len, data, &SHARED_VTABLE)
+}
+
+unsafe fn shared_v_to_vec(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> Vec<u8> {
+ let shared: *mut Shared = data.load(Ordering::Relaxed).cast();
+
+ if (*shared).is_unique() {
+ let shared = &mut *shared;
+
+ // Drop shared
+ let mut vec = mem::replace(&mut shared.vec, Vec::new());
+ release_shared(shared);
+
+ // Copy back buffer
+ ptr::copy(ptr, vec.as_mut_ptr(), len);
+ vec.set_len(len);
+
+ vec
+ } else {
+ let v = slice::from_raw_parts(ptr, len).to_vec();
+ release_shared(shared);
+ v
+ }
+}
+
+unsafe fn shared_v_drop(data: &mut AtomicPtr<()>, _ptr: *const u8, _len: usize) {
+ data.with_mut(|shared| {
+ release_shared(*shared as *mut Shared);
+ });
+}
+
+// compile-fails
+
+/// ```compile_fail
+/// use bytes::BytesMut;
+/// #[deny(unused_must_use)]
+/// {
+/// let mut b1 = BytesMut::from("hello world");
+/// b1.split_to(6);
+/// }
+/// ```
+fn _split_to_must_use() {}
+
+/// ```compile_fail
+/// use bytes::BytesMut;
+/// #[deny(unused_must_use)]
+/// {
+/// let mut b1 = BytesMut::from("hello world");
+/// b1.split_off(6);
+/// }
+/// ```
+fn _split_off_must_use() {}
+
+/// ```compile_fail
+/// use bytes::BytesMut;
+/// #[deny(unused_must_use)]
+/// {
+/// let mut b1 = BytesMut::from("hello world");
+/// b1.split();
+/// }
+/// ```
+fn _split_must_use() {}
+
+// fuzz tests
+#[cfg(all(test, loom))]
+mod fuzz {
+ use loom::sync::Arc;
+ use loom::thread;
+
+ use super::BytesMut;
+ use crate::Bytes;
+
+ #[test]
+ fn bytes_mut_cloning_frozen() {
+ loom::model(|| {
+ let a = BytesMut::from(&b"abcdefgh"[..]).split().freeze();
+ let addr = a.as_ptr() as usize;
+
+ // test the Bytes::clone is Sync by putting it in an Arc
+ let a1 = Arc::new(a);
+ let a2 = a1.clone();
+
+ let t1 = thread::spawn(move || {
+ let b: Bytes = (*a1).clone();
+ assert_eq!(b.as_ptr() as usize, addr);
+ });
+
+ let t2 = thread::spawn(move || {
+ let b: Bytes = (*a2).clone();
+ assert_eq!(b.as_ptr() as usize, addr);
+ });
+
+ t1.join().unwrap();
+ t2.join().unwrap();
+ });
+ }
+}
diff --git a/third_party/rust/bytes/src/fmt/debug.rs b/third_party/rust/bytes/src/fmt/debug.rs
new file mode 100644
index 0000000000..83de695dd7
--- /dev/null
+++ b/third_party/rust/bytes/src/fmt/debug.rs
@@ -0,0 +1,49 @@
+use core::fmt::{Debug, Formatter, Result};
+
+use super::BytesRef;
+use crate::{Bytes, BytesMut};
+
+/// Alternative implementation of `std::fmt::Debug` for byte slice.
+///
+/// Standard `Debug` implementation for `[u8]` is comma separated
+/// list of numbers. Since large amount of byte strings are in fact
+/// ASCII strings or contain a lot of ASCII strings (e. g. HTTP),
+/// it is convenient to print strings as ASCII when possible.
+impl Debug for BytesRef<'_> {
+ fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+ write!(f, "b\"")?;
+ for &b in self.0 {
+ // https://doc.rust-lang.org/reference/tokens.html#byte-escapes
+ if b == b'\n' {
+ write!(f, "\\n")?;
+ } else if b == b'\r' {
+ write!(f, "\\r")?;
+ } else if b == b'\t' {
+ write!(f, "\\t")?;
+ } else if b == b'\\' || b == b'"' {
+ write!(f, "\\{}", b as char)?;
+ } else if b == b'\0' {
+ write!(f, "\\0")?;
+ // ASCII printable
+ } else if (0x20..0x7f).contains(&b) {
+ write!(f, "{}", b as char)?;
+ } else {
+ write!(f, "\\x{:02x}", b)?;
+ }
+ }
+ write!(f, "\"")?;
+ Ok(())
+ }
+}
+
+impl Debug for Bytes {
+ fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+ Debug::fmt(&BytesRef(self.as_ref()), f)
+ }
+}
+
+impl Debug for BytesMut {
+ fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+ Debug::fmt(&BytesRef(self.as_ref()), f)
+ }
+}
diff --git a/third_party/rust/bytes/src/fmt/hex.rs b/third_party/rust/bytes/src/fmt/hex.rs
new file mode 100644
index 0000000000..97a749a336
--- /dev/null
+++ b/third_party/rust/bytes/src/fmt/hex.rs
@@ -0,0 +1,37 @@
+use core::fmt::{Formatter, LowerHex, Result, UpperHex};
+
+use super::BytesRef;
+use crate::{Bytes, BytesMut};
+
+impl LowerHex for BytesRef<'_> {
+ fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+ for &b in self.0 {
+ write!(f, "{:02x}", b)?;
+ }
+ Ok(())
+ }
+}
+
+impl UpperHex for BytesRef<'_> {
+ fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+ for &b in self.0 {
+ write!(f, "{:02X}", b)?;
+ }
+ Ok(())
+ }
+}
+
+macro_rules! hex_impl {
+ ($tr:ident, $ty:ty) => {
+ impl $tr for $ty {
+ fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+ $tr::fmt(&BytesRef(self.as_ref()), f)
+ }
+ }
+ };
+}
+
+hex_impl!(LowerHex, Bytes);
+hex_impl!(LowerHex, BytesMut);
+hex_impl!(UpperHex, Bytes);
+hex_impl!(UpperHex, BytesMut);
diff --git a/third_party/rust/bytes/src/fmt/mod.rs b/third_party/rust/bytes/src/fmt/mod.rs
new file mode 100644
index 0000000000..676d15fc21
--- /dev/null
+++ b/third_party/rust/bytes/src/fmt/mod.rs
@@ -0,0 +1,5 @@
+mod debug;
+mod hex;
+
+/// `BytesRef` is not a part of public API of bytes crate.
+struct BytesRef<'a>(&'a [u8]);
diff --git a/third_party/rust/bytes/src/lib.rs b/third_party/rust/bytes/src/lib.rs
new file mode 100644
index 0000000000..af436b3162
--- /dev/null
+++ b/third_party/rust/bytes/src/lib.rs
@@ -0,0 +1,117 @@
+#![warn(missing_docs, missing_debug_implementations, rust_2018_idioms)]
+#![doc(test(
+ no_crate_inject,
+ attr(deny(warnings, rust_2018_idioms), allow(dead_code, unused_variables))
+))]
+#![no_std]
+#![cfg_attr(docsrs, feature(doc_cfg))]
+
+//! Provides abstractions for working with bytes.
+//!
+//! The `bytes` crate provides an efficient byte buffer structure
+//! ([`Bytes`](struct.Bytes.html)) and traits for working with buffer
+//! implementations ([`Buf`], [`BufMut`]).
+//!
+//! [`Buf`]: trait.Buf.html
+//! [`BufMut`]: trait.BufMut.html
+//!
+//! # `Bytes`
+//!
+//! `Bytes` is an efficient container for storing and operating on contiguous
+//! slices of memory. It is intended for use primarily in networking code, but
+//! could have applications elsewhere as well.
+//!
+//! `Bytes` values facilitate zero-copy network programming by allowing multiple
+//! `Bytes` objects to point to the same underlying memory. This is managed by
+//! using a reference count to track when the memory is no longer needed and can
+//! be freed.
+//!
+//! A `Bytes` handle can be created directly from an existing byte store (such as `&[u8]`
+//! or `Vec<u8>`), but usually a `BytesMut` is used first and written to. For
+//! example:
+//!
+//! ```rust
+//! use bytes::{BytesMut, BufMut};
+//!
+//! let mut buf = BytesMut::with_capacity(1024);
+//! buf.put(&b"hello world"[..]);
+//! buf.put_u16(1234);
+//!
+//! let a = buf.split();
+//! assert_eq!(a, b"hello world\x04\xD2"[..]);
+//!
+//! buf.put(&b"goodbye world"[..]);
+//!
+//! let b = buf.split();
+//! assert_eq!(b, b"goodbye world"[..]);
+//!
+//! assert_eq!(buf.capacity(), 998);
+//! ```
+//!
+//! In the above example, only a single buffer of 1024 is allocated. The handles
+//! `a` and `b` will share the underlying buffer and maintain indices tracking
+//! the view into the buffer represented by the handle.
+//!
+//! See the [struct docs] for more details.
+//!
+//! [struct docs]: struct.Bytes.html
+//!
+//! # `Buf`, `BufMut`
+//!
+//! These two traits provide read and write access to buffers. The underlying
+//! storage may or may not be in contiguous memory. For example, `Bytes` is a
+//! buffer that guarantees contiguous memory, but a [rope] stores the bytes in
+//! disjoint chunks. `Buf` and `BufMut` maintain cursors tracking the current
+//! position in the underlying byte storage. When bytes are read or written, the
+//! cursor is advanced.
+//!
+//! [rope]: https://en.wikipedia.org/wiki/Rope_(data_structure)
+//!
+//! ## Relation with `Read` and `Write`
+//!
+//! At first glance, it may seem that `Buf` and `BufMut` overlap in
+//! functionality with `std::io::Read` and `std::io::Write`. However, they
+//! serve different purposes. A buffer is the value that is provided as an
+//! argument to `Read::read` and `Write::write`. `Read` and `Write` may then
+//! perform a syscall, which has the potential of failing. Operations on `Buf`
+//! and `BufMut` are infallible.
+
+extern crate alloc;
+
+#[cfg(feature = "std")]
+extern crate std;
+
+pub mod buf;
+pub use crate::buf::{Buf, BufMut};
+
+mod bytes;
+mod bytes_mut;
+mod fmt;
+mod loom;
+pub use crate::bytes::Bytes;
+pub use crate::bytes_mut::BytesMut;
+
+// Optional Serde support
+#[cfg(feature = "serde")]
+mod serde;
+
+#[inline(never)]
+#[cold]
+fn abort() -> ! {
+ #[cfg(feature = "std")]
+ {
+ std::process::abort();
+ }
+
+ #[cfg(not(feature = "std"))]
+ {
+ struct Abort;
+ impl Drop for Abort {
+ fn drop(&mut self) {
+ panic!();
+ }
+ }
+ let _a = Abort;
+ panic!("abort");
+ }
+}
diff --git a/third_party/rust/bytes/src/loom.rs b/third_party/rust/bytes/src/loom.rs
new file mode 100644
index 0000000000..9e6b2d5e25
--- /dev/null
+++ b/third_party/rust/bytes/src/loom.rs
@@ -0,0 +1,30 @@
+#[cfg(not(all(test, loom)))]
+pub(crate) mod sync {
+ pub(crate) mod atomic {
+ pub(crate) use core::sync::atomic::{AtomicPtr, AtomicUsize, Ordering};
+
+ pub(crate) trait AtomicMut<T> {
+ fn with_mut<F, R>(&mut self, f: F) -> R
+ where
+ F: FnOnce(&mut *mut T) -> R;
+ }
+
+ impl<T> AtomicMut<T> for AtomicPtr<T> {
+ fn with_mut<F, R>(&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<T> {}
+ }
+}
diff --git a/third_party/rust/bytes/src/serde.rs b/third_party/rust/bytes/src/serde.rs
new file mode 100644
index 0000000000..0a5bd144a9
--- /dev/null
+++ b/third_party/rust/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<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+ where
+ S: Serializer,
+ {
+ serializer.serialize_bytes(&self)
+ }
+ }
+
+ struct $visitor_ty;
+
+ impl<'de> de::Visitor<'de> for $visitor_ty {
+ type Value = $ty;
+
+ fn expecting(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
+ formatter.write_str("byte array")
+ }
+
+ #[inline]
+ fn visit_seq<V>(self, mut seq: V) -> Result<Self::Value, V::Error>
+ where
+ V: de::SeqAccess<'de>,
+ {
+ let len = cmp::min(seq.size_hint().unwrap_or(0), 4096);
+ let mut values: Vec<u8> = Vec::with_capacity(len);
+
+ while let Some(value) = seq.next_element()? {
+ values.push(value);
+ }
+
+ Ok($ty::$from_vec(values))
+ }
+
+ #[inline]
+ fn visit_bytes<E>(self, v: &[u8]) -> Result<Self::Value, E>
+ where
+ E: de::Error,
+ {
+ Ok($ty::$from_slice(v))
+ }
+
+ #[inline]
+ fn visit_byte_buf<E>(self, v: Vec<u8>) -> Result<Self::Value, E>
+ where
+ E: de::Error,
+ {
+ Ok($ty::$from_vec(v))
+ }
+
+ #[inline]
+ fn visit_str<E>(self, v: &str) -> Result<Self::Value, E>
+ where
+ E: de::Error,
+ {
+ Ok($ty::$from_slice(v.as_bytes()))
+ }
+
+ #[inline]
+ fn visit_string<E>(self, v: String) -> Result<Self::Value, E>
+ where
+ E: de::Error,
+ {
+ Ok($ty::$from_vec(v.into_bytes()))
+ }
+ }
+
+ impl<'de> Deserialize<'de> for $ty {
+ #[inline]
+ fn deserialize<D>(deserializer: D) -> Result<$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);
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-16 10:37:55 +0000