(Breaking Changes) Re-implement tracing wrapper in a safer way, replacing the use of &str with &[u8].#1071
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ehuss merged 2 commits intorust-lang:masterfrom Jan 4, 2025
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…moke test, update tracing callback to use `&[u8]` instead of `&str`.
This was referenced Jul 22, 2024
ehuss
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Jan 4, 2025
| // Test that using the above function to set a tracing callback doesn't panic. | ||
| #[test] | ||
| fn smoke() { | ||
| super::trace_set(TraceLevel::Trace, |level, msg| { |
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Just noting that since this is a global, we can't really have multiple tests for this. And this is registering a trace function that triggers for all tests running after this. That might be ok, but something we'll need to be careful of.
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This changes the type signature of
TracingCbto use a&[u8]over an&str, leaving the conversion to the consumer as planned. This is a breaking change and will require a new release.Internally, this replaces the use of a static
AtomicUsizeto store the tracing subscriber with aAtomicPtr. This is still unsafe, but lets us avoid the integer to pointer transmutation that was previously happening which is more explicitly a possible violation of Rust's memory model. Now all the casts and transmutations intracing.rsare between pointer types, which is (relatively) safer.