Struct bytes::buf::UninitSlice[][src]

#[repr(transparent)]
pub struct UninitSlice(_);
Expand description

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.

Implementations

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) };

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[..]);

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[..]);

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();

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);

Trait Implementations

Formats the value using the given formatter. Read more

The returned type after indexing.

Performs the indexing (container[index]) operation. Read more

The returned type after indexing.

Performs the indexing (container[index]) operation. Read more

The returned type after indexing.

Performs the indexing (container[index]) operation. Read more

The returned type after indexing.

Performs the indexing (container[index]) operation. Read more

The returned type after indexing.

Performs the indexing (container[index]) operation. Read more

The returned type after indexing.

Performs the indexing (container[index]) operation. Read more

Performs the mutable indexing (container[index]) operation. Read more

Performs the mutable indexing (container[index]) operation. Read more

Performs the mutable indexing (container[index]) operation. Read more

Performs the mutable indexing (container[index]) operation. Read more

Performs the mutable indexing (container[index]) operation. Read more

Performs the mutable indexing (container[index]) operation. Read more

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more