Stream: git-wasmtime

Topic: wasmtime / PR #11612 make `Destination::as_direct` work f...

Wasmtime GitHub notifications bot (Sep 04 2025 at 23:59):

dicej requested alexcrichton for a review on PR #11612.

Wasmtime GitHub notifications bot (Sep 04 2025 at 23:59):

dicej requested rvolosatovs for a review on PR #11612.

Wasmtime GitHub notifications bot (Sep 04 2025 at 23:59):

dicej opened PR #11612 from dicej:unconditional-destination-as-direct to bytecodealliance:main:

In order to reduce code duplication (and code paths to test) in wasmtime-wasi and custom host embeddings, I've made Destination::as_direct (formerly known as as_direct_destination) work for host readers as well as guest ones. In the process, I noticed and fixed a couple of related issues:

• I had forgotten to implement or test host reader support in DirectSource :facepalm:
• The code to support host-to-host pipes failed to account for partial reads

I've also simplified the StreamConsumer and StreamProducer APIs slightly by having them take their Source and Destination parameters by value rather than by reference, respectively.

Note that, per https://github.com/WebAssembly/component-model/issues/561, I've tweaked the documentation for StreamProducer to indicate that implementations might reasonably opt to "pretend" they're ready without buffering any items when handling zero-length reads given that buffering has its own hazards. Likewise, I've updated the wasi-filesystem and wasi-cli implementations to "pretend" instead of buffering.

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Wasmtime GitHub notifications bot (Sep 04 2025 at 23:59):

dicej requested wasmtime-wasi-reviewers for a review on PR #11612.

Wasmtime GitHub notifications bot (Sep 04 2025 at 23:59):

dicej requested wasmtime-core-reviewers for a review on PR #11612.

Wasmtime GitHub notifications bot (Sep 05 2025 at 00:14):

alexcrichton submitted PR review.

Wasmtime GitHub notifications bot (Sep 05 2025 at 00:39):

alexcrichton merged PR #11612.

Last updated: Dec 06 2025 at 06:05 UTC