[fU] ClassLoader --> LoadableClass relationship obsolete

[stephan b. <st...@ei...>]

Yo,

i've just finished a rough draft for a DLL-using classloader which takes 
it's BaseType (a-la LoadableClass) via a template parameter. Under this 
model the LoadableClass --> ClassLoader explicit relationship is 
obsolete.


Current caveats:

- it's template based, so it's implemented in a header file. (It's not 
/so/ big, though.)

- it (somehow) loads classes which do not derive from the BaseType, and 
i have no idea how/why it's doing it. This /might/ not be a problem in 
practice, but it sure is bugging the hell out of me (HTF is the  
dynamic_cast<BaseType*>(NonDerived*) actually working???).



Consider:
    class LoadableClass {...}
    class Foo : public LoadableClass {...}
    class Bar : public LoadableClass {...}
    class Unrelated {...}

typedef DLLLoader<LoadableClass> CL;
CL cl;
CL::value_type * obj = cl.load( "Foo" ); // finds Foo
obj = cl.load( "Bar" ); // finds Bar
obj = cl.load( "Unrelated" );
// somehow actually loads Unrelated as a LoadableClass(!?!?),
// but it shouldn't.

i don't have the code in the fun tree yet, but i'll move it all over 
once i'm happier with how it's working. After putting the s11n tree 
into fun this weekend i spent the rest of the weekend in a major 
refactoring session so i could:
a) pull out some of the code that s11n is dependent on.
b) make the non-removable code more project-portable, so i can maintain 
copies in elib and libfun without significant hassles.

So, the LoadableClass classloader is now just a typedef:

typedef DLLLoader<LoadableClass> ClassLoader;

The loader can also take statically-registered factory functions. When i 
loads a class from an INSTANTIATOR func it maps that function back to 
it's registered factories, so the parent class (non-DLL-aware) can 
handle future requests for a given key.


DLLLoader.cpp:11 : check_for_dll_bootstrap(0x40014f50 , main )
DLLLoader.cpp:20 : running DLLLoader_bootstrap()
../../../include/elib/DLLLoader.h:189 : No DLL found for key 'Car'. 
Looking in main() space.
../../../include/elib/DLLLoader.h:234 : Found instantiator new_Car()
playground.cpp:152 : l[Car]=0x80af1b8 class=LoadableClass
playground.cpp:48 : Car::foo()
playground.cpp:153 : l[Car]=0x8126008 class=LoadableClass
playground.cpp:48 : Car::foo()
playground.cpp:154 : l[Car]=0x812cd18 class=LoadableClass
playground.cpp:48 : Car::foo()
playground.cpp:155 : l[Truck]=0x8128cb0 class=LoadableClass
playground.cpp:99 : Truck::foo()
../../../include/elib/DLLLoader.h:189 : No DLL found for key 
'Unrelated'. Looking in main() space.
../../../include/elib/DLLLoader.h:234 : Found instantiator 
new_Unrelated()
playground.cpp:156 : l[Unrelated]=0x8124ec0 class=LoadableClass
playground.cpp:69 : Unrelated::foo()
../../../include/elib/DLLLoader.h:189 : No DLL found for key 
'Unloadable'. Looking in main() space.
playground.cpp:157 : l[Unloadable]=0
../../../include/elib/DLLLoader.h:194 : Found DLL for 
'LoadableSubclass': ./LoadableSubclass.so
DLLLoader.cpp:11 : check_for_dll_bootstrap(0x80a0390 , LoadableSubclass 
)
DLLLoader.cpp:17 : no DLLLoader_bootstrap() found in 0x80a0390
../../../include/elib/DLLLoader.h:234 : Found instantiator 
new_LoadableSubclass()
playground.cpp:158 : l[LoadableSubclass]=0x80f2570 class=LoadableClass
LoadableSubclass.cpp:5 : LoadableSubclass::foo()


-- 
----- st...@ei... - http://www.einsurance.de
"... it's up to other companies to ensure interoperability."
-- Bill Gates
http://www.nydailynews.com/city_life/tech/story/84722p-77434c.html