[Y!!]

For discussion/bugtracking about the extension.

[Raoul]

Hi Y!!,
I've downloaded your EMutex extension, and I have a question on how it works. Really, I didn't notice any problem, that's just I would like to understand better the basic principles of your mutex.
I'm probable wrong but it seems to me that in a particular case, 2 php threads could get the same mutex.
On the lock method, you wrote :

file_put_contents($path, serialize(array($timeout, time())), LOCK_EX);

This is the only command that is garanteed to be atomic right ? Then, 2 php threads could execute all previous lines, and reach this one sequencially .. isn't it ?

Thread 1> if (false !== $data && (0 === $data[0] || $data[0] + $data[1] > time()))
Thread 2> if (false !== $data && (0 === $data[0] || $data[0] + $data[1] > time()))

Thread 2 > array_push($this->_locks, $id);
Thread 1 > array_push($this->_locks, $id);

Thread 1 > file_put_contents($path, serialize(array($timeout, time())), LOCK_EX);
Thread 2 > file_put_contents($path, serialize(array($timeout, time())), LOCK_EX);

// both thread have the mutex !!

Of course, that is very bad luck, but from a formal point of view, this is possible no ?
Please, could you tell me if and why I'm wrong ...
thanks

[Y!!]

Hehe good find. Yes I think it's possible. Though, under some crazy circumstances since the time-difference between checking and writing the lock file is probably under 3ms. I'm not really sure yet what a good fix would be, probably the use of flock() with only one global lock file (that hold's all locks in a serialized array)?

[Y!!]

I updated the extension.

- All locks in one file
- Now using microtime() for more precise timeout
- Some other enhancements

[Raoul]

that it greay Y!! .. As I told you, I never had any problem with EMutex, my question was just theorical, but I apreciate you new enhancments and this time, it seems that there can't be any Mutex 'collision' ...even theorically
Thanks
ciao

[jptsetung]

That's an awesoem extension, exactly what I was looking for. Thx!