1 /*****************************************************************************
2 * modules_core.h : Module management functions used by the core application.
3 *****************************************************************************
4 * Copyright (C) 2001 VideoLAN
5 * $Id: modules_core.h,v 1.5 2001/03/21 13:42:33 sam Exp $
7 * Authors: Samuel Hocevar <sam@zoy.org>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
22 *****************************************************************************/
24 /*****************************************************************************
25 * Inline functions for handling dynamic modules
26 *****************************************************************************/
28 /*****************************************************************************
29 * module_load: load a dynamic library
30 *****************************************************************************
31 * This function loads a dynamically linked library using a system dependant
32 * method, and returns a non-zero value on error, zero otherwise.
33 *****************************************************************************/
35 module_load( char * psz_filename, module_handle_t * handle )
38 *handle = load_add_on( psz_filename );
39 return( *handle < 0 );
41 /* Do not open modules with RTLD_GLOBAL, or we are going to get namespace
42 * collisions when two modules have common public symbols */
43 *handle = dlopen( psz_filename, RTLD_NOW );
45 return( *handle == NULL );
49 /*****************************************************************************
50 * module_unload: unload a dynamic library
51 *****************************************************************************
52 * This function unloads a previously opened dynamically linked library
53 * using a system dependant method. No return value is taken in consideration,
54 * since some libraries sometimes refuse to close properly.
55 *****************************************************************************/
56 static __inline__ void
57 module_unload( module_handle_t handle )
60 unload_add_on( handle );
67 /*****************************************************************************
68 * module_getsymbol: get a symbol from a dynamic library
69 *****************************************************************************
70 * This function queries a loaded library for a symbol specified in a
71 * string, and returns a pointer to it.
72 * FIXME: under Unix we should maybe check for dlerror() instead of the
73 * return value of dlsym, since we could have loaded a symbol really set
74 * to NULL (quite unlikely, though).
75 *****************************************************************************/
76 static __inline__ void *
77 module_getsymbol( module_handle_t handle, char * psz_function )
81 if( B_OK == get_image_symbol( handle, psz_function,
82 B_SYMBOL_TYPE_TEXT, &p_symbol ) )
91 #elif defined(SYS_DARWIN1_3)
92 /* MacOS X dl library expects symbols to begin with "_". That's
93 * really lame, but hey, what can we do ? */
94 char * psz_call = malloc( strlen( psz_function ) + 2 );
96 strcpy( psz_call + 1, psz_function );
99 p_return = dlsym( handle, psz_call );
105 return( dlsym( handle, psz_function ) );
109 /*****************************************************************************
110 * module_error: wrapper for dlerror()
111 *****************************************************************************
112 * This function returns the error message of the last module operation. It
113 * returns the string "failed" on systems which do not have the dlerror()
115 *****************************************************************************/
116 static __inline__ const char *