Dynamic Libraryes, C++ and Objective-C

Dynamic Libraryes, C++ and Objective-C

[Bruno Moreira Guedes]

Hello People,

I'm highly interested in developing a "very-pluggable API", to offer a
"Java API-like"(just LIKE hehehe) for C++. So, I asked myself "how
could I dynamic load classes?". During my research about how to
construct that, I break into that step, and it's getting too hard to
pass...

After a little research, I heard about a 'ugly' method which consists
of creating a virtual/pure-virtual and class using a helper function
to make the new/delete operations.

But I want to "split" the API into a base library, statically linked
with the base libraries, and the "pluggable parts", where each part
consists of a set of many classes. So, creating a virtual class for
each class don't make sense...

Researching anymor I heard about a Objective-C ability of creating and
modifying classes during the runtime. But I don't know Objective-C
very-well and I don't know how to 'mix' it with C++ code... As an
alternative, if someone could help-me about using GCC to mix that, I'm
grateful...

But returning to the main problem, I want to use the headers which I
have of the API parts, of course... And the I get the idea of letting
the symbols to be resolved during the library loading stage, and not
during the compile time...
There's anyway to don't resolve the symbols during the compile-time???

Re: Dynamic Libraryes, C++ and Objective-C

[Lawrence Crowl]

On 1/1/08, Bruno Moreira Guedes <thbmatrix@gmail.com> wrote:
> Hello People,
>
> I'm highly interested in developing a "very-pluggable API", to offer a
> "Java API-like"(just LIKE hehehe) for C++. So, I asked myself "how
> could I dynamic load classes?". During my research about how to
> construct that, I break into that step, and it's getting too hard to
> pass...
>
> After a little research, I heard about a 'ugly' method which consists
> of creating a virtual/pure-virtual and class using a helper function
> to make the new/delete operations.
>
> But I want to "split" the API into a base library, statically linked
> with the base libraries, and the "pluggable parts", where each part
> consists of a set of many classes. So, creating a virtual class for
> each class don't make sense...
>
> Researching anymor I heard about a Objective-C ability of creating and
> modifying classes during the runtime. But I don't know Objective-C
> very-well and I don't know how to 'mix' it with C++ code... As an
> alternative, if someone could help-me about using GCC to mix that, I'm
> grateful...
>
> But returning to the main problem, I want to use the headers which I
> have of the API parts, of course... And the I get the idea of letting
> the symbols to be resolved during the library loading stage, and not
> during the compile time...
> There's anyway to don't resolve the symbols during the compile-time???

Your best bet is probably to define a simple function that is a factory
for implementation classes derived from the interface's abstract base
classes.  Each plug-in would define the factory.

-- 
Lawrence Crowl