silver-ymz opened a new pull request, #3004: URL: https://github.com/apache/incubator-opendal/pull/3004
## Explanation `std::istream` is more like `BufRead` in rust, so I expose `struct Reader(BufReader<od::BlockingReader>)`. Otherwise, we need to impl a `BufReader` in c++ which will bring more unsafe code and it's more difficult to maintain. `std::streambuf` use three following pointers to track buffer state. c++ side needs to update these pointers with rust buffer state. My implementation is to call [`fill_buf`](https://doc.rust-lang.org/1.72.0/std/io/trait.BufRead.html#tymethod.fill_buf) and [`seek`](https://doc.rust-lang.org/1.72.0/std/io/trait.Seek.html#tymethod.seek) in needed and assign [`buffer`](https://doc.rust-lang.org/1.72.0/std/io/struct.BufReader.html#method.buffer) result to the three pointers. And we call [`consume`](https://doc.rust-lang.org/1.72.0/std/io/trait.BufRead.html#tymethod.consume) in the next `fill_buf` and `seek` operation to update c++ info for rust side. <img width="234" alt="image" src="https://github.com/apache/incubator-opendal/assets/78400701/79bdbd1a-a99f-41ff-a729-64458cc0baa2";> -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
