Use std::lock_guard for exception safety in ThreadSafeMap and ThreadSafeQueue#157
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davideberly merged 1 commit intodavideberly:masterfrom Feb 28, 2026
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…afeQueue All methods used manual mMutex.lock()/mMutex.unlock() instead of RAII. If any operation between lock and unlock throws (e.g., copy constructor, map insertion), the mutex would never be unlocked, causing deadlock. Replaced all manual lock/unlock pairs with std::lock_guard<std::mutex>. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Summary
ThreadSafeMap.handThreadSafeQueue.hused manualmMutex.lock()/mMutex.unlock()instead of RAIIvalue = iter->second, map insertion inmMap[key] = value), the mutex would never be unlocked, causing a deadlockstd::lock_guard<std::mutex>, which guarantees unlock on scope exit regardless of exceptionsTest plan
This fix is structural (exception-safety improvement). The bug only manifests when a copy/move constructor throws while the mutex is held, which requires a specially crafted throwing type. The behavioral change is that mutex unlock is now guaranteed in all code paths.
Verified that the files compile correctly and the API is unchanged.
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