/*
 * Thu Mar  6 09:17:56 CET 2003
 * <spd@daphne.cps.unizar.es>
 *
 * Minimal plug-in sample code
 *
 */


#include <stdio.h>
#include <limits.h>

#ifdef __DARWIN__
# include <mach-o/dyld.h>
# define SHLT	NSModule
#else
# include <dlfcn.h>
# define SHLT	void *
#endif


int	mint=0;
SHLT	load(char *name,float (**fun)(float));
int	unload(SHLT module);

main( int		argc, char	**argv)
{
	SHLT	mod;
	float	x;
	float	(*f)(float);


	if (argc<2)
	{
		fprintf(stderr,"Usage: %s object_file\n",argv[0]);
		exit(1);
	}

	/* Carga del objeto. Devuelve 1 si lo consigue */
	if(NULL!=(mod=load(argv[1],&f)))
	{
		for (x=0; x<10; x++)
		{
			printf("f(%f) = %f\n",x,f(x));
			mint++;
		}
	}
	unload(mod);
}

void init( void )
{
	static int a=0;

	if (a == 0)
	{
		puts("Init");
		a++ ;
	}
}

#ifndef __DARWIN__
SHLT	load(char *name,float (**fun)(float))
{
	void	*coderef;
	char	*errstr;
	int		res;
	char	ename[PATH_MAX];
	char	**ident;

	*fun = NULL;

	printf("Loading %s\n",name);
/*	sprintf(ename, "./%s", name);*/
	sprintf(ename, "%s", name);

	res = 0;
	/*
	 * Intenta abrir el fichero objeto, Devuelve NULL si no lo encuentra,
	 * 	si lo encuentra devuelve una referencia al trozo de codigo y
	 * 	variables
	 *
	 * RTLD_NOW es para que todas las referencias a variables que haya
	 * 	en el fichero se resuelvan en el momento de la carga
	 */
    coderef = dlopen(ename,RTLD_NOW);
    if (coderef != NULL)
    {
		/* Acceso a una funcion */
        *fun = dlsym(coderef,"fun");
		if ( res = (*fun != NULL))
		{
			if ( NULL == ( ident = (char **)dlsym(coderef, "_name")))
			{
				fprintf(stderr,"can't get name\n");
			}
			else
			{
				fprintf(stderr,"name: (%p) %s\n", *ident, *ident);
			}
		}
    }
    if ((errstr=dlerror()) != NULL) fprintf(stderr,"%s\n",errstr);

	return coderef;
}

int	unload(SHLT module)
{
	int res = dlclose(module);
	if (res)
	{
		perror("dlclose");
		return 1;
	}
	return 0;
}

#else
SHLT	load(char *name,float (**fun)(float))
{
	NSObjectFileImage			image;
	NSObjectFileImageReturnCode	result;
	NSModule					handle = NULL;
	NSSymbol					symbol;
	void						*sym;
	char						**ident;
	const char*					err = NULL;


	printf("Loading %s\n",name);

	result = NSCreateObjectFileImageFromFile(name, &image);
	if (result == NSObjectFileImageSuccess)
	{
		handle = NSLinkModule(image,name,NSLINKMODULE_OPTION_RETURN_ON_ERROR);
		/* If something went wrong, get the errors... */
		if (!handle)
		{
			NSLinkEditErrors c;
			int errornumber;
			const char *filename;
			NSLinkEditError(&c, &errornumber, &filename, &err);
		}
		NSDestroyObjectFileImage(image);
	}
	else if ((
			result == NSObjectFileImageFormat ||
			result == NSObjectFileImageInappropriateFile))
	{
		err = "invalid MH_BUNDLE file";
	}
	else
	{
		err = "unable to create object file image";
	}

	if (err==NULL)
	{
		if (NULL==(symbol = NSLookupSymbolInModule(handle,"__name")))
		{
			fprintf(stderr,"can't get name\n");
		}
		else if (NULL!=(ident = (char **)NSAddressOfSymbol(symbol)))
		{
			fprintf(stderr,"name: (%p) %s\n", *ident, *ident);
		}
		fflush(stderr);

		if (NULL==(symbol = NSLookupSymbolInModule(handle,"_fun")))
		{
			err = "undefined";
		}
		else if (NULL==(*fun = NSAddressOfSymbol(symbol)))
		{
			err = "can't resolve address";
			*fun=0;
		}
	}
	if ( NULL != err )
	{
		fprintf(stderr,"Err: %s\n",err);
	}

	return handle;
}

int	unload(SHLT module)
{
	NSUnLinkModule(module, FALSE);
	return 0;
}

#endif