wasip3: Improve/fix handling of buffered reads#793
Merged
alexcrichton merged 1 commit intoWebAssembly:mainfrom Apr 22, 2026
Merged
wasip3: Improve/fix handling of buffered reads#793alexcrichton merged 1 commit intoWebAssembly:mainfrom
alexcrichton merged 1 commit intoWebAssembly:mainfrom
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This updates the code path that performs a buffered read for a stream when zero-length reads/writes are determined to not signal readiness correctly. Specifically a defensive assertion that this is a nonzero-length read is added and additionally in the case that I/O completes immediately the return code is handled appropriately. Unfortunately I don't know of a way to test this as it's not testable from Wasmtime today and the file streams implementation in Wasmtime ends up sort of accidentally respecting the zero-length protocol (sort of). Thus, for now, this is just a code change until more comprehensive testing such as WebAssembly#766 is implemented.
dicej
approved these changes
Apr 22, 2026
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This updates the code path that performs a buffered read for a stream when zero-length reads/writes are determined to not signal readiness correctly. Specifically a defensive assertion that this is a nonzero-length read is added and additionally in the case that I/O completes immediately the return code is handled appropriately. Unfortunately I don't know of a way to test this as it's not testable from Wasmtime today and the file streams implementation in Wasmtime ends up sort of accidentally respecting the zero-length protocol (sort of). Thus, for now, this is just a code change until more comprehensive testing such as #766 is implemented.