fix: data race between libddwaf.Load() and libddwaf.Usable()
#149
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A data race existed between `libddwaf.Load()` and `libddwaf.Usable()` as both access shared global state that is not managed through atomic pointers. This PR puts the shared state behind atomics so that the data race no longer exists. We copy the `wafLib` pointer in the `Builder`, `Handle` and `Context` structures to avoid having to load the atomic all the time, which would have broad performance impact.
RamyElkest
approved these changes
Aug 11, 2025
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A data race existed between
libddwaf.Load()andlibddwaf.Usable()as both access shared global state that is not managed through atomic pointers.This PR adds a
sync.Mutexto resolve the race condition betweenLoadandUsable; as the use of async.OnceinLoadensures there is no race condition in other places (all uses of thegWafLibare guaranteed to be preceded by a call toLoad, which means the reads "synchronize after" the write).