use assert etc. in Wine dlls? What is better?

[Michael Stefaniuc]

Hello Joerg,

On 03/13/2012 03:05 PM, Joerg-Cyril.Hoehle at t-systems.com wrote:
> Maarten's wine-pulse contains several instances of assert()
> I've been thinking about adding a bit of protection against
> inconcsistencies within mmdevapi code too.
> 
> There are two variants that could be applicable depending on the situation:
> /* this should not happen, but if we detect it early, we can work-around the situation */
> if (a > limit) { ERR("%d > %d\n", a, limit); a = limit; }
> or
> assert(a <= limit, "whatever %d", a);
> 
> I'm not too fond of assert.  An assert in DSound was one of my first bug
> fixes in Wine, years ago. It was not obvious why the app should not
> continue running -- perhaps without sound.
> OTOH, if an assert is violated, as a programmer, I'd like to hear about it.
> 
> I found little on that topic in Wine. In 2002, Alexandre Julliard wrote:
> http://www.winehq.org/pipermail/wine-devel/2002-October/009766.html
>> A better approach would be to leave assert() alone, and raise an
>> exception on the SIGABRT signal.
> 
> What is current opinion on this topic?
there are quite a few assert calls used in the dlls:
git grep -w assert dlls | grep -v "include" | wc -l
1509

But of course the correct answer when to add an assert is as always "It
depends" ;)
- If some internal state got corrupt and the app has no way to recover
but crash later on it is better to assert as early as possible as that
simplifies the debugging.
- If the app has a chance to deal with the error then returning an error
is the better approach. Add an ERR() or WARN() to that so we at least
can see the issue.

bye
	michael