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-rw-r--r--third_party/rust/bytes/src/buf/buf_mut.rs1088
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diff --git a/third_party/rust/bytes/src/buf/buf_mut.rs b/third_party/rust/bytes/src/buf/buf_mut.rs
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+++ b/third_party/rust/bytes/src/buf/buf_mut.rs
@@ -0,0 +1,1088 @@
+use core::{cmp, mem::{self, MaybeUninit}, ptr, usize};
+
+#[cfg(feature = "std")]
+use std::fmt;
+
+use alloc::{vec::Vec, boxed::Box};
+
+/// 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 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 `bytes_mut`.
+ ///
+ /// # 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.
+ fn remaining_mut(&self) -> usize;
+
+ /// Advance the internal cursor of the BufMut
+ ///
+ /// The next call to `bytes_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);
+ ///
+ /// unsafe {
+ /// // MaybeUninit::as_mut_ptr
+ /// buf.bytes_mut()[0].as_mut_ptr().write(b'h');
+ /// buf.bytes_mut()[1].as_mut_ptr().write(b'e');
+ ///
+ /// buf.advance_mut(2);
+ ///
+ /// buf.bytes_mut()[0].as_mut_ptr().write(b'l');
+ /// buf.bytes_mut()[1].as_mut_ptr().write(b'l');
+ /// buf.bytes_mut()[2].as_mut_ptr().write(b'o');
+ ///
+ /// 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.bytes_mut()[0].as_mut_ptr().write(b'h');
+ /// buf.bytes_mut()[1].as_mut_ptr().write(b'e');
+ ///
+ /// buf.advance_mut(2);
+ ///
+ /// buf.bytes_mut()[0].as_mut_ptr().write(b'l');
+ /// buf.bytes_mut()[1].as_mut_ptr().write(b'l');
+ /// buf.bytes_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. `bytes_mut` should return an empty
+ /// slice **if and only if** `remaining_mut` returns 0. In other words,
+ /// `bytes_mut` returning an empty slice implies that `remaining_mut` will
+ /// return 0 and `remaining_mut` returning 0 implies that `bytes_mut` will
+ /// return an empty slice.
+ fn bytes_mut(&mut self) -> &mut [MaybeUninit<u8>];
+
+ /// Fills `dst` with potentially multiple mutable slices starting at `self`'s
+ /// current position.
+ ///
+ /// If the `BufMut` is backed by disjoint slices of bytes, `bytes_vectored_mut`
+ /// enables fetching more than one slice at once. `dst` is a slice of
+ /// mutable `IoSliceMut` references, enabling the slice to be directly used with
+ /// [`readv`] without any further conversion. The sum of the lengths of all
+ /// the buffers in `dst` will be less than or equal to
+ /// `Buf::remaining_mut()`.
+ ///
+ /// The entries in `dst` will be overwritten, but the data **contained** by
+ /// the slices **will not** be modified. If `bytes_vectored_mut` 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., `BufMut::remaining_mut` returns 0, calls to `bytes_vectored_mut` must
+ /// return 0 without mutating `dst`.
+ ///
+ /// Implementations should also take care to properly handle being called
+ /// with `dst` being a zero length slice.
+ ///
+ /// [`readv`]: http://man7.org/linux/man-pages/man2/readv.2.html
+ #[cfg(feature = "std")]
+ fn bytes_vectored_mut<'a>(&'a mut self, dst: &mut [IoSliceMut<'a>]) -> usize {
+ if dst.is_empty() {
+ return 0;
+ }
+
+ if self.has_remaining_mut() {
+ dst[0] = IoSliceMut::from(self.bytes_mut());
+ 1
+ } else {
+ 0
+ }
+ }
+
+ /// 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.bytes();
+ let d = self.bytes_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.bytes_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); }
+ }
+ }
+
+ /// 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 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 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 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 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 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 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 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 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 a signed 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_int(0x010203, 3);
+ /// assert_eq!(buf, b"\x01\x02\x03");
+ /// ```
+ ///
+ /// # Panics
+ ///
+ /// This function panics if there is not enough remaining capacity in
+ /// `self`.
+ fn put_int(&mut self, n: i64, nbytes: usize) {
+ self.put_slice(&n.to_be_bytes()[mem::size_of_val(&n) - nbytes..]);
+ }
+
+ /// Writes a signed n-byte integer to `self` in little-endian byte order.
+ ///
+ /// The current position is advanced by `nbytes`.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use bytes::BufMut;
+ ///
+ /// let mut buf = vec![];
+ /// buf.put_int_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_int_le(&mut self, n: i64, nbytes: usize) {
+ self.put_slice(&n.to_le_bytes()[0..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 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());
+ }
+}
+
+macro_rules! deref_forward_bufmut {
+ () => (
+ fn remaining_mut(&self) -> usize {
+ (**self).remaining_mut()
+ }
+
+ fn bytes_mut(&mut self) -> &mut [MaybeUninit<u8>] {
+ (**self).bytes_mut()
+ }
+
+ #[cfg(feature = "std")]
+ fn bytes_vectored_mut<'b>(&'b mut self, dst: &mut [IoSliceMut<'b>]) -> usize {
+ (**self).bytes_vectored_mut(dst)
+ }
+
+ 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_i16(&mut self, n: i16) {
+ (**self).put_i16(n)
+ }
+
+ fn put_i16_le(&mut self, n: i16) {
+ (**self).put_i16_le(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_i32(&mut self, n: i32) {
+ (**self).put_i32(n)
+ }
+
+ fn put_i32_le(&mut self, n: i32) {
+ (**self).put_i32_le(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_i64(&mut self, n: i64) {
+ (**self).put_i64(n)
+ }
+
+ fn put_i64_le(&mut self, n: i64) {
+ (**self).put_i64_le(n)
+ }
+ )
+}
+
+impl<T: BufMut + ?Sized> BufMut for &mut T {
+ deref_forward_bufmut!();
+}
+
+impl<T: BufMut + ?Sized> BufMut for Box<T> {
+ deref_forward_bufmut!();
+}
+
+impl BufMut for &mut [u8] {
+ #[inline]
+ fn remaining_mut(&self) -> usize {
+ self.len()
+ }
+
+ #[inline]
+ fn bytes_mut(&mut self) -> &mut [MaybeUninit<u8>] {
+ // MaybeUninit is repr(transparent), so safe to transmute
+ unsafe { mem::transmute(&mut **self) }
+ }
+
+ #[inline]
+ unsafe fn advance_mut(&mut self, cnt: usize) {
+ // Lifetime dance taken from `impl Write for &mut [u8]`.
+ let (_, b) = core::mem::replace(self, &mut []).split_at_mut(cnt);
+ *self = b;
+ }
+}
+
+impl BufMut for Vec<u8> {
+ #[inline]
+ fn remaining_mut(&self) -> usize {
+ usize::MAX - self.len()
+ }
+
+ #[inline]
+ unsafe fn advance_mut(&mut self, cnt: usize) {
+ let len = self.len();
+ let remaining = self.capacity() - len;
+ if cnt > remaining {
+ // Reserve additional capacity, and ensure that the total length
+ // will not overflow usize.
+ self.reserve(cnt);
+ }
+
+ self.set_len(len + cnt);
+ }
+
+ #[inline]
+ fn bytes_mut(&mut self) -> &mut [MaybeUninit<u8>] {
+ use core::slice;
+
+ 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() as *mut MaybeUninit<u8>;
+ unsafe {
+ &mut slice::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.bytes();
+ l = s.len();
+ self.extend_from_slice(s);
+ }
+
+ src.advance(l);
+ }
+ }
+
+ fn put_slice(&mut self, src: &[u8]) {
+ self.extend_from_slice(src);
+ }
+}
+
+// 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) {}
+
+// ===== impl IoSliceMut =====
+
+/// A buffer type used for `readv`.
+///
+/// This is a wrapper around an `std::io::IoSliceMut`, but does not expose
+/// the inner bytes in a safe API, as they may point at uninitialized memory.
+///
+/// This is `repr(transparent)` of the `std::io::IoSliceMut`, so it is valid to
+/// transmute them. However, as the memory might be uninitialized, care must be
+/// taken to not *read* the internal bytes, only *write* to them.
+#[repr(transparent)]
+#[cfg(feature = "std")]
+pub struct IoSliceMut<'a>(std::io::IoSliceMut<'a>);
+
+#[cfg(feature = "std")]
+impl fmt::Debug for IoSliceMut<'_> {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ f.debug_struct("IoSliceMut")
+ .field("len", &self.0.len())
+ .finish()
+ }
+}
+
+#[cfg(feature = "std")]
+impl<'a> From<&'a mut [u8]> for IoSliceMut<'a> {
+ fn from(buf: &'a mut [u8]) -> IoSliceMut<'a> {
+ IoSliceMut(std::io::IoSliceMut::new(buf))
+ }
+}
+
+#[cfg(feature = "std")]
+impl<'a> From<&'a mut [MaybeUninit<u8>]> for IoSliceMut<'a> {
+ fn from(buf: &'a mut [MaybeUninit<u8>]) -> IoSliceMut<'a> {
+ IoSliceMut(std::io::IoSliceMut::new(unsafe {
+ // We don't look at the contents, and `std::io::IoSliceMut`
+ // doesn't either.
+ mem::transmute::<&'a mut [MaybeUninit<u8>], &'a mut [u8]>(buf)
+ }))
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2025-02-09 14:45:18 +0000