There's no reason the user should be forced to wrap it in BufReader in
case the trait is needed, because the Reader has all the bits for
supporting it naturally.
The property the Buff and BuffMut can return shorter slice is quite an
important detail. Nevertheless, while it is mentioned in the
documentation, the wording makes it relatively easy to overlook. This
tries to bring more attention to it.
With this if foo is a mutable slice, it is possible to do
foo.into_buf().put_u32_le(42);
Before this patch into_buf would create a Cursor<&'a [u8]> and it
would not be possible to write into it.
With this if foo is a mutable slice, it is possible to do
foo.into_buf().put_u32_le(42);
Before this patch into_buf would create a Cursor<&'a [u8]> and it
would not be possible to write into it.
* Recycle space when reserving from Vec-backed Bytes
BytesMut::reserve, when called on a BytesMut instance which is backed by
a non-shared Vec<u8>, would previously just delegate to Vec::reserve
regardless of the current location in the buffer. If the Bytes is
actually the trailing component of a larger Vec, then the unused space
won't be recycled. In applications which continually move the pointer
forward to consume data as it comes in, this can cause the underlying
buffer to get extremely large.
This commit checks whether there's extra space at the start of the
backing Vec in this case, and reuses the unused space if possible
instead of allocating.
* Avoid excessive copying when reusing Vec space
Only reuse space in a Vec-backed Bytes when doing so would gain back
more than half of the current capacity. This avoids excessive copy
operations when a large buffer is almost (but not completely) full.
* Recycle space when reserving from Vec-backed Bytes
BytesMut::reserve, when called on a BytesMut instance which is backed by
a non-shared Vec<u8>, would previously just delegate to Vec::reserve
regardless of the current location in the buffer. If the Bytes is
actually the trailing component of a larger Vec, then the unused space
won't be recycled. In applications which continually move the pointer
forward to consume data as it comes in, this can cause the underlying
buffer to get extremely large.
This commit checks whether there's extra space at the start of the
backing Vec in this case, and reuses the unused space if possible
instead of allocating.
* Avoid excessive copying when reusing Vec space
Only reuse space in a Vec-backed Bytes when doing so would gain back
more than half of the current capacity. This avoids excessive copy
operations when a large buffer is almost (but not completely) full.
This patch fixes the `copy_to_slice` function, rectifying the logic.
However, the incorrect code does not result in incorrect behavior as the
only case `cnt != src.len()` is during the final iteration, and since
`src.len()` is greater than `cnt` in that case, `off` will be
incremented by too much, but this will still trigger the `off <
dst.len()` condition.
The only danger is `src.len()` could cause an overflow.
* 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.
- 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.
Fixes#163
Sean McArthur