Free up resources on SIGTERM and SIGINT

[dgraziotin]

Make the structures extern
Free up al mallocs on SIGTERM and SIGINT

[Yamakaky]

Why ? Isn't is freed anyway at the end of the program ?

[dgraziotin]

This is what I would think, too.

However, valgrind keeps bothering me about some possible memory leaks. And I see that there are mixed feelings regarding what to do when a program exits.

My conclusion is that it would be a good practice to free the resources on those two signals. However, I do not see that as something urgent to be done. One day, I will fix this. Meanwhile, it does not harm.

[Yamakaky]

OK ^^

[Yamakaky]

As we are here, I read somewhere that it's better to only set flags conditionally and read them in the main loop, as there can be race problems between two signals. Here, it doesn't mind but it's good practice.

[oliviertilmans]

While you're at it:
Beside free'ing up the structure, you should consider putting back the fans to auto so that they are managed again by applesmc.

I wanted to submit a pull request for that by since it required to expose the structures and you're doing it I figured I'd just suggest it.

[Yamakaky]

That's a good idea.

[dgraziotin]

@oliviertilmans thank you! That is really a good idea, indeed. I did not know that there was a way to put them to "auto". It was probably not possible when I first developed mbpfan 2 years ago. Anyway, how does it work? Is there some documentation regarding it? Is it just a echo "auto"?

[oliviertilmans]

Simply handle back the control to the applesmc driver à la

echo "0" > /sys/devices/platform/applesmc.768/fan1_manual

[dgraziotin]

@oliviertilmans...it was pretty easy. Thanks! This goes to #46