Wasm32 Compatibility: Unexpected HTTP Range Values When Handling Large Files

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Description:

I'm developing a Rust library that is primarily designed for native environments but also offers WASM bindings. On the WASM side, I use a HTTP client implementation (via gloo_net) and have implemented the AsyncHttpRangeClient trait from the http-range-client from the crate to fetch data via HTTP range requests.

What I Want to Do:

• Large File Access in WASM: I aim to efficiently fetch portions of very large files using HTTP range requests in a wasm32 environment, replicating native functionality.
• Maintain API Interoperability: I wish to keep using the current API by reusing the AsyncBufferedHttpRangeClient and AsyncHttpRangeClient traits without needing to diverge from the existing design.

The Issue:

• In a wasm32 environment, when the client tries to request a range that exceeds the maximum value of a 32‑bit integer (i.e., beyond u32::MAX), integer overflows occur. This is because, on wasm32, the Rust type usize is interpreted as a 32‑bit value.
• As a result, HTTP range requests are sent with unexpected values, leading to misaligned or incorrect data being fetched.
• This behavior seems to be directly linked to the limitations of the wasm32 memory model and its handling of 32‑bit addressable units.

Inquiry:

• Has anyone encountered this issue in a wasm32 context when handling large file requests?
• Are there any known workarounds or design suggestions to effectively manage large file offsets while avoiding these integer overflow issues on wasm32?