Fix atomicity violation in set_logger_racy using compare_exchange

[quantpoet]

This commit fixes a race condition in set_logger_racy where multiple threads could simultaneously initialize different loggers.

The fix uses atomic compare_exchange to ensure only one thread can transition from UNINITIALIZED to INITIALIZING state, eliminating the TOCTOU bug while preserving the original API.

[KodrAus]

Thanks for the PR @quantpoet.

set_logger_racy is racy by definition, and is intended for embedded environments that don’t have multiple threads. As a caller you’re required to ensure there is only a single call to the function. Since the compare exchange here isn’t actually atomic I don’t think it really buys us any additional safety.

[quantpoet]

Thanks for the PR @quantpoet.

set_logger_racy is racy by definition, and is intended for embedded environments that don’t have multiple threads. As a caller you’re required to ensure there is only a single call to the function. Since the compare exchange here isn’t actually atomic I don’t think it really buys us any additional safety.

Oh indeed. Thanks for your reply!