Utils::LockGuard

1 Introduction

LockGuard is a RAII-wrapper around Os::Mutex, essentially allowing scoped lock and unlock. It works the same way as C++11 std::lock_guard.

If a section of code has only basic lock/unlock requirements, LockGuard ensures that early exits from that section will always release the lock.

2 Usage

2.1 Basic

LockGuard is a class that can be included and instantiated with an associated Os::Mutex reference.

#include <Utils/LockGuard.hpp>
...
Os::Mutex mutex;
LockGuard lock(mutex);

The moment LockGuard is instantiated, it will attempt to lock the mutex that's given to it.

LockGuard is meant for scoped use, i.e. it should always live on a function call stack. It allows a sometimes more convenient way of using mutex, e.g. you want this entire function locked from this point forward, and early returns should be guaranteed to release the lock.

LockGuard _lock(mutex);
...
if (xyz) {
  return 0; // will unlock mutex
}
if (abc) {
  return 1; // will unlock mutex
}
return 2; // will unlock mutex

It can also be used for a smaller scope

```cpp if (xyz) { LockGuard _lock(mutex); ... } // will unlock mutex