QReadLocker unlock question

[touusen]

I have some code like this, but I do not know if readLocker.unlock(); is safe or not.
thanks for advice.

QReadLocker readLocker(&locker);

Login login(name, password);
if (!login.isLoggedIn()) {
    return false;
}

readLocker.unlock();   
onUserChanged();      //signal

[JonB]

@touusen
In what sense " is safe or not"? Your code looks fine to me (assuming what you want to protect is just the Login object and the isLoggedIn() call).

[touusen]

@JonB
Thank you.
I mean , the locker will be unlocked when the QMutexLocker is destroyed,
but I used readLocker.unlock() to unlock the locker manually and I have no idea about the status of locker when QMutexLocker is destroyed.

[JonB]

@touusen
I'm still not understanding your doubt. QReadLocker will release the lock when it goes out of scope or explicitly if you call QReadLocker::unlock().

[touusen]

@JonB
In my code, does QReadLocker release the lock twice?
(① readLocker.unlock(); ②out of scope)

[JonB]

@touusen

• QReadLocker::unlock() call will unlock/release the lock.
• QReadLocker out-of-scope destructor will unlock/release the lock if it holds a lock. You should assume if it has already unlocked/released it will not do it a second time.

Did you actually try your code? Since you seem to be so worried about it, and are not comfortable with answers, why don't you do so to reassure yourself at this point?

[touusen]

@JonB
Thank you very much.