snippets

#include <mutex>

class LockGuard {
public:
    explicit LockGuard(std::mutex& m) : mtx(m) { mtx.lock(); }
    ~LockGuard() { mtx.unlock(); }
    LockGuard(const LockGuard&) = delete;
    LockGuard& operator=(const LockGuard&) = delete;
private:
    std::mutex& mtx;
};