I find this diagram very helpful, but a little hard to distinguish
between the boxes and the lines that connect them. This commit redraws
the boxes with line drawing characters so that the boxes appear a
little more solid, and stand out from the other lines.
* Optimize `BytesMut::reserve`: Reuse vec if possible
If the `BytesMut` holds a unqiue reference to `KIND_ARC` while the
capacity of the `Vec` is not big enough , reuse the existing `Vec`
instead of allocating a new one.
Signed-off-by: Jiahao XU <[email protected]>
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`.
Avoid allocation when `Take` or `Chain` is composed of `Bytes`
objects.
This works now for `Take`.
`Chain` it works if the requested bytes does not cross boundary
between `Chain` members.
This appears to be the primary cause of significant performance
regressions in the `prost` test suite in the 0.5 to 0.6 transition. See
danburkert/prost#381.
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
This method replaces `Buf::to_bytes()`, providing a method that copies a
subset of the remaining buffer into a `Bytes` value. As this is strictly
more flexible, `to_bytes()` is removed.
Fixes: #129, #398
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
The previous description focussed a lot on the `Arc` based implementation
of `Bytes`. Given the vtable based implemetation, this is however not the
only valid implementation. This changes the description a bit in order
to de-emaphasize the `Arc` part, and to describe that other implementations
are possible.
This should also be necessary if the vtable gets public.
