[14.0.0]: Add an error resource to WASI streams #7169
Merged
alexcrichton merged 1 commit intoOct 6, 2023
Merged
Conversation
* Change `bindgen!`'s trappable error to take an input type This commit removes the generated type for `trappable_error_type` from the `bindgen!` macro to allow users to provide a type instead. This works similarly as before with new conversion functions generated in traits which are used to convert the custom error into the ABI representation of what a WIT world expects. There are a few motivations for this commit: * This enables reducing the number of errors in play between async/sync bindings by using the same error type there. * This avoids an auto-generated type which is more difficult to inspect than one that's written down already and the source can more easily be inspected. * This enables richer conversions using `self` (e.g. `self.table_mut()`) between error types rather than purely relying on `Into`. This is important for bytecodealliance#7017 where an error is going to be inserted into the table as it gets converted. * Fix tests * Update WASI to use new trappable errors This commit deals with the fallout of the previous commit for the WASI preview2 implementation. The main changes here are: * Bindgen-generated `Error` types no longer exist. These are replaced with `TrappableError<T>` where type aliases are used such as ```rust type FsError = TrappableError<wasi::filesystem::types::ErrorCode>; ``` * Type synonyms such as `FsResult<T>` are now added for more conveniently writing down fallible signatures. * Some various error conversions are updated from converting to the old `Error` type to now instead directly into corresponding `ErrorCode` types. * A number of cases where unknown errors were turned into traps now return bland error codes and log the error instead since these aren't fatal events. * The `StreamError` type does not use `TrappableError` since it has other variants that it's concerned with such as a `LastOperationFailed` variant which has an `anyhow::Error` payload. * Some minor preview1 issues were fixed such as trapping errors being turned into normal I/O errors by accident. * Add an `error` resource to WASI streams This commit adds a new `error` resource to the `wasi:io/streams` interface. This `error` resource is returned as part of `last-operation-failed` and serves as a means to discover through other interfaces more granular type information than a generic string. This error type has a new function in the `filesystem` interface, for example, which enables getting filesystem-related error codes from I/O performed on filesystem-originating streams. This is plumbed through to the adapter as well to return more than `ERRNO_IO` from failed read/write operations now too. This is not super fancy just yet but is intended to be a vector through which future additions can be done. The main thing this enables is to avoid dropping errors on the floor in the host and enabling the guest to discover further information about I/O errors on streams. Closes bytecodealliance#7017 * Update crates/wasi-http/wit/deps/io/streams.wit Co-authored-by: Trevor Elliott <awesomelyawesome@gmail.com> * Update wasi-http wit too * Remove unnecessary clone --------- Co-authored-by: Trevor Elliott <awesomelyawesome@gmail.com>
elliottt
approved these changes
Oct 6, 2023
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
This is a backport of #7152 to the 14 release branch.