mirror of
https://github.com/openharmony/third_party_rust_bytes.git
synced 2026-07-18 16:24:29 -04:00
Noah Zentzis
2491e5102d
* 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.