Embeddable Common-Lisp

Julian Stecklina wrote:

>If I compile a lisp source file via ecl -compile -s in order to link
>it together with a C stub to produce a shared library, I have to
>initialize the lisp part.
>After some investigation I found out that I have to call 
>read_VV(OBJNULL, init_SYSTEM); 
>to make the definitions in system.lisp become effective.  Is this
>documented somewhere or am I wrong?
>
>  
>
Hmm, I see you have been a bad boy and tried to guess the mechanism for 
library initialization :-) I would rather advice you to stay away from 
it and use C::BUILD-SHARED-LIBRARY and the :PROLOGUE-CODE and 
:EPILOGUE-CODE if you need to have some special C code that has to be 
executed before or after the lisp part is initialized.

If you definitively cannot do this then you might try to mimic the 
output of BUILD-SHARED-LIBRARY, which is based on the template 
+lisp-program-init+ and in turn uses read_VV. The first argument to 
read_VV is a codeblock object, that keeps information about the module 
you are building: i.e., what the data of the library is, its text 
representation, the file it comes from, etc. If you supply OBJNULL to 
read_VV, such an object is created for you.

This mechanism is not documented because it is prone to change and 
because, as I told you, there's a higher level interface that takes care 
of all this stuff.

Regards,

Juanjo

Juan Jose Garcia Ripoll <lisp@...> writes:

> Hmm, I see you have been a bad boy and tried to guess the mechanism for library initialization :-) I would rather advice you to
> stay away from it and use C::BUILD-SHARED-LIBRARY and the :PROLOGUE-CODE and :EPILOGUE-CODE if you need to have some special C
> code that has to be executed before or after the lisp part is initialized.

What I need is an "entry" function that I can call. The functionality
provided by build-shared-library is of no use to me. My code looks
something like:

void init_plugin(...)
{
        cl_boot(...);

        /* Initialise wrapper functions */
        /* and some variables */
        wrap_functions();

        /* Load the definitions from the lisp object */
        init_list_part();

        return;
}

The main problem is that init_plugin is the entry function that is
called when the shared library is loaded. 
Looking over the code I guess one could add a :init-function keyword
parameter to the builder function and have it construct a function
that I can call whenever it suits me. 

> This mechanism is not documented because it is prone to change and because, as I told you, there's a higher level interface that
> takes care of all this stuff.

I understand, but I do not believe that it is usable for shared
libraries as is. 

Regards,
-- 
                    ____________________________
 Julian Stecklina  /  _________________________/
  ________________/  /
  \_________________/  LISP - truly beautiful

Julian Stecklina wrote:

>What I need is an "entry" function that I can call. The functionality
>provided by build-shared-library is of no use to me. My code looks
>something like:
>
>void init_plugin(...)
>{
>        cl_boot(...);
>
>        /* Initialise wrapper functions */
>        /* and some variables */
>        wrap_functions();
>
>        /* Load the definitions from the lisp object */
>        init_list_part();
>
>        return;
>}
>The main problem is that init_plugin is the entry function that is
>called when the shared library is loaded. 
>Looking over the code I guess one could add a :init-function keyword
>parameter to the builder function and have it construct a function
>that I can call whenever it suits me. 
>
I have done this. Now there is an extra keyword argument, :INIT-NAME, 
that customizes the name of the entry point in a DLL, library or 
program. I hope this helps.

I hope I did not seem to stubborn in the previous emails, but the fact 
is that this initialization code is indeed very fragile and might easily 
change in near future. For instance, depending on the garbage collector 
you choose, one might need to do something different, like registering 
the library with the GC. The BUILD-* routines currently take care of that.

Juanjo

Juan Jose Garcia Ripoll <lisp@...> writes:

> I have done this. Now there is an extra keyword argument, :INIT-NAME,
> that customizes the name of the entry point in a DLL, library or
> program. I hope this helps.

I will try as soon as anon cvs catches up. Thanks!

> I hope I did not seem to stubborn in the previous emails, but the fact
> is that this initialization code is indeed very fragile and might
> easily change in near future. For instance, depending on the garbage
> collector you choose, one might need to do something different, like
> registering the library with the GC. The BUILD-* routines currently
> take care of that.

No problem.

Regards,
-- 
                    ____________________________
 Julian Stecklina  /  _________________________/
  ________________/  /
  \_________________/  LISP - truly beautiful