Equivalent to
```
for _ in 0..cnt {
self.put_u8(val);
}
```
but may work faster.
Name and signature is chosen to be consistent with `ptr::write_bytes`.
Include three specializations:
* `Vec<u8>`
* `&mut [u8]`
* `BytesMut`
`BytesMut` and `&mut [u8]` specializations use `ptr::write`, `Vec<u8>`
specialization uses `Vec::resize`.
The `bytes()` / `bytes_mut()` name implies the method returns the full
set of bytes represented by `Buf`/`BufMut`. To rectify this, the methods
are renamed to `chunk()` and `chunk_mut()` to reflect the partial nature
of the returned byte slice.
`bytes_vectored()` is renamed `chunks_vectored()`.
Closes#447
The way BufMut uses MaybeUninit can lead to unsoundness. This replaces
MaybeUnit with a type owned by bytes so we can ensure the usage patterns
are sound.
Refs: #328
This brings `BytesMut` in line with `Vec<u8>` behavior.
This also fixes an existing bug in BytesMut::bytes_mut that exposes
invalid slices. The bug was recently introduced and was only on master
and never released to `crates.io`.
In order to fix a test, `BufMutExt::chain_mut` is provided. Withou this,
it is not possible to chain two `&mut [u8]`.
Closes#170
- The return type of `BufMut::bytes_mut` is now
`&mut [MaybeUninit<u8>]`.
- The argument type of `BufMut::bytes_vectored_mut` is now
`&mut [bytes::buf::IoSliceMut]`.
- `bytes::buf::IoSliceMut` is a `repr(transparent)` wrapper around an
`std::io::IoSliceMut`, but does not expose the inner bytes with a safe
API, since they might be uninitialized.
- `BufMut::bytesMut` and `BufMut::bytes_vectored_mut` are no longer
`unsafe fn`, since the types encapsulate the unsafety instead.
Bytes is a useful tool for managing multiple slices into the same region
of memory, and the other things it used to have been removed to reduce
complexity. The exact strategy for managing the multiple references is
no longer hard-coded, but instead backing by a customizable vtable.
- Removed ability to mutate the underlying memory from the `Bytes` type.
- Removed the "inline" (SBO) mechanism in `Bytes`. The reduces a large
amount of complexity, and improves performance when accessing the
slice of bytes, since a branch is no longer needed to check if the
data is inline.
- Removed `Bytes` knowledge of `BytesMut` (`BytesMut` may grow that
knowledge back at a future point.)
As consequence Buf::collect is removed as well, which is replaced with `Buf::into_bytes`. The advantage of `Buf::into_bytes` is that it can be optimized in cases where converting a `T: Buf` into a `Bytes` instance is efficient.
* make Buf and BufMut usable as trait objects
- All the `get_*` and `put_*` methods that take `T: ByteOrder` have
a `where Self: Sized` bound added, so that they are only usable from
sized types. It was impossible to make `Buf` or `BufMut` into trait
objects before, so this change doesn't break anyone.
- Add `get_n_be`/`get_n_le`/`put_n_be`/`put_n_le` methods that can be
used on trait objects.
- Deprecate the export of `ByteOrder` and methods generic on it.
* remove deprecated ByteOrder methods
Removes the `_be` suffix from all methods, implying that the default
people should use is network endian.
