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/*
Copyright (C) 2010 Andreas Baumann <abaumann@yahoo.com>
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "library/loader.h"
#include <stdlib.h> /* for EXIT_SUCCESS, EXIT_FAILURE */
#include <stdio.h> /* for fprintf */
#include <assert.h> /* for assert */
int main( void ) {
wolf_library_p library;
wolf_error_t error;
char errbuf[512];
typedef int (*multiply_by_two_func)( int );
union { multiply_by_two_func func; void *obj; } alias;
void *symbol;
multiply_by_two_func func;
int res = 0;
/* open the libray */
library = wolf_library_load( "./testlib.so.0.0.0", &error );
if( error != WOLF_OK ) {
fprintf( stderr, "Error %d loading the library: %s\n",
error, wolf_library_errmsg( error, library, errbuf, 512 ) );
return EXIT_FAILURE;
}
/* fetch a known function symbol (multiply_by_two), for the reasons why naive
* casting doesn't work, see:
* http://en.wikipedia.org/wiki/Dynamic_loading
*/
symbol = wolf_library_get( library, "multiply_by_two", &error );
alias.obj = symbol;
func = alias.func;
/* call it */
res = func( 7 );
assert( res == 14 );
/* close library */
error = wolf_library_unload( library );
if( error != WOLF_OK ) {
fprintf( stderr, "Error %d unloading the library: %s\n",
error, wolf_library_errmsg( error, library, errbuf, 512 ) );
return EXIT_FAILURE;
}
return EXIT_SUCCESS;
}
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