[geos-devel] initGEOS/finishGEOS and multiple subsystems

[Mateusz Loskot]

Frank Warmerdam wrote:
> Mateusz Loskot wrote:
>> strk at refractions.net wrote:
>>> With GEOS-3.0.0 initGEOS/finishGEOS do not instantiate/delete a
>>> GeometryFactory anymore. Rather the default GeometryFactory is
>>> used. This should fix the problem.
>> 
>> What about backport to 2.2.x with ref-counted proposal? Such
>> changes could would not affect existing code.
>> 
>> I'd like to repeat that in general, global factory should be
>> replaced with shared object (e.g. managed by shared_ptr from Boost
>> or our own home-made shared smart pointer). static factory can
>> cause problems too: 
>> http://www.parashift.com/c++-faq-lite/ctors.html#faq-10.12
> 
> Mateusz,
> 
> I personally hate static objects of any complexity because I don't 
> like a lot of randomly ordered stuff happening before main() even 
> starts.

Frank,

yes, that's the problem.

> I would much prefer the referenced counted implementation in 2.2.x
> and in head.  I'm not sure how smart pointers would help since the
> functions don't return a handle for the caller to hold.

Yes, you mean initGEOS does not return any pointer/handle.
but I had in mind global static factory, recently replaced with lazy
initialized one:

const GeometryFactory*
GeometryFactory::getDefaultInstance()
{
	static GeometryFactory defInstance;
	return &defInstance;
}



BTW, boost::smart_ptr is implemented as ref-counted:
http://www.boost.org/libs/smart_ptr/shared_ptr.htm

Cheers
-- 
Mateusz Loskot
http://mateusz.loskot.net