Enable extended patterns in fnmatch

[tsipinakis]

I wanted to add a compilation warning but apparently #warning is a gcc specific extension. Not sure how else we could indicate if this is enabled or not.

Fixes #645
Fixes #658

[bebehei]

Nice and clean solution. But I've been getting the suspicious if this is a good solution to solve our problem. I've got absolutely no knowledge, how GLib and other libs are working when compiling multiple units with different sources and linking them.

[tsipinakis]

I've got absolutely no knowledge, how GLib and other libs are working when compiling multiple units with different sources and linking them.

Theoretically this should not play a role at all. Either the GNU extensions exist in libc or they don't our definitions do not affect that. All it does is control if they are exported in the header to allow us to use them.

See fnmatch.h, fnmatch.c.

[tsipinakis]

But I've been getting the suspicious if this is a good solution to solve our problem

I've been getting suspicious too but for an entirely different reason - I'm unsure if fnmatch is the best fit here. As the manpage mentions it's intended for paths and while it does what we need I feel like regex would be a better fit.

[bebehei]

To achieve negative matching, I guess we either have to implement such "quirk" and document it right or allow regexes.

TBH, I'd prefer the fnmatch thing ... if it wouldn't be such a weird mess.

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Just to evaluate a possible regex path: How would we implement it? While thinking about it, I guess,. you had some ideas. We can't have it as a drop-in replacement. Chars like .?\()[] would have a complete different meaning now.

[tsipinakis]

We can't have it as a drop-in replacement. Chars like .?()[] would have a complete different meaning now.

I was thinking using something like a tilde as a prefix for it, so appname = "firefox" uses fnmatch and `appname = "~firefox" uses regex.

[bebehei]

I was thinking using something like a tilde as a prefix for it, so appname = "firefox" uses fnmatch and `appname = "~firefox" uses regex.

What about a slash? I guess it's more intuitive.

[tsipinakis]

I'll close this as, as said above it's better to add an option to use regex rather than enable extended patterns.