Remove uses of `enum`

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Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
35/100
Issue type
Refactor
Clarity
Mostly clear
Activity status
Stale
Tech stack
rust
Domain
operating-systems

Research direction

Start by reviewing the existing cases where C enums are mapped to constants, then read the linked bindgen context and the discussion in rust-bindgen issue #2646. Determine the scope of enum uses to remove and whether an enum! macro is needed. Done means the affected bindings avoid unsafe Rust enums while preserving the C values across platforms.

Written by the indexing model from the issue text.

Description

I-unsound 💥

Rust enums become UB if they hold an unexpected value, while C enums are effectively a grouped list of named constants. This causes easy UB if e.g. C adds a value or returns a value not represented by the enum (as is allowed in C), and this value gets passed to Rust.

The easiest thing to do is map enums to constants, which we already do in most cases. We could also consider an enum! macro that figures out the values.

Some more context is at https://mdaverde.com/posts/rust-bindgen-enum/ and https://github.com/rust-lang/rust-bindgen/issues/2646.

Dominant language
Rust
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Forks
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Avg merge
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Merged PRs (30d)
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Getting set up

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

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