1 /*****************************************************************************
2 * os.c : Low-level dynamic library handling
3 *****************************************************************************
4 * Copyright (C) 2001-2007 the VideoLAN team
7 * Authors: Sam Hocevar <sam@zoy.org>
8 * Ethan C. Baldridge <BaldridgeE@cadmus.com>
9 * Hans-Peter Jansen <hpj@urpla.net>
10 * Gildas Bazin <gbazin@videolan.org>
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
25 *****************************************************************************/
31 #include <vlc_common.h>
32 #include <vlc_plugin.h> /* MODULE_SUFFIX */
36 #include <stdlib.h> /* free(), strtol() */
37 #include <stdio.h> /* sprintf() */
38 #include <string.h> /* strdup() */
40 #ifdef HAVE_SYS_TYPES_H
41 # include <sys/types.h>
44 #if !defined(HAVE_DYNAMIC_PLUGINS)
45 /* no support for plugins */
46 #elif defined(HAVE_DL_DYLD)
47 # if defined(HAVE_MACH_O_DYLD_H)
48 # include <mach-o/dyld.h>
50 #elif defined(HAVE_DL_BEOS)
51 # if defined(HAVE_IMAGE_H)
54 #elif defined(HAVE_DL_WINDOWS)
56 #elif defined(HAVE_DL_DLOPEN)
57 # if defined(HAVE_DLFCN_H) /* Linux, BSD, Hurd */
60 # if defined(HAVE_SYS_DL_H)
63 #elif defined(HAVE_DL_SHL_LOAD)
64 # if defined(HAVE_DL_H)
68 #ifdef HAVE_VALGRIND_VALGRIND_H
69 # include <valgrind/valgrind.h>
72 /*****************************************************************************
74 *****************************************************************************/
75 #ifdef HAVE_DYNAMIC_PLUGINS
76 static void *module_Lookup( module_handle_t, const char * );
78 #if defined(HAVE_DL_WINDOWS)
79 static char * GetWindowsError ( void );
85 * Call a symbol given its name and a module structure. The symbol MUST
86 * refer to a function returning int and taking a module_t* as an argument.
87 * \param p_module the modules
88 * \return 0 if it pass and -1 in case of a failure
90 int module_Call( vlc_object_t *obj, module_t *p_module )
92 static const char psz_name[] = "vlc_entry" MODULE_SUFFIX;
93 int (* pf_symbol) ( module_t * p_module );
95 /* Try to resolve the symbol */
96 pf_symbol = (int (*)(module_t *)) module_Lookup( p_module->handle,
99 if( pf_symbol == NULL )
101 #if defined(HAVE_DL_DYLD) || defined(HAVE_DL_BEOS)
102 msg_Warn( obj, "cannot find symbol \"%s\" in file `%s'",
103 psz_name, p_module->psz_filename );
104 #elif defined(HAVE_DL_WINDOWS)
105 char *psz_error = GetWindowsError();
106 msg_Warn( obj, "cannot find symbol \"%s\" in file `%s' (%s)",
107 psz_name, p_module->psz_filename, psz_error );
109 #elif defined(HAVE_DL_DLOPEN)
110 msg_Warn( obj, "cannot find symbol \"%s\" in file `%s' (%s)",
111 psz_name, p_module->psz_filename, dlerror() );
112 #elif defined(HAVE_DL_SHL_LOAD)
113 msg_Warn( obj, "cannot find symbol \"%s\" in file `%s' (%m)",
114 psz_name, p_module->psz_filename );
116 # error "Something is wrong in modules.c"
121 /* We can now try to call the symbol */
122 if( pf_symbol( p_module ) != 0 )
124 /* With a well-written module we shouldn't have to print an
125 * additional error message here, but just make sure. */
126 msg_Err( obj, "Failed to call symbol \"%s\" in file `%s'",
127 psz_name, p_module->psz_filename );
131 /* Everything worked fine, we can return */
135 #if defined (RTLD_NOLOAD)
136 /* Make sure libvlccore is in the global namespace */
137 static void load_libvlccore( void )
139 if( !dlsym( RTLD_DEFAULT, "libvlc_Quit" )
140 && !dlopen( "libvlccore.so", RTLD_GLOBAL|RTLD_NOLOAD ) )
141 fprintf( stderr, "ERROR: failed loading libvlccore\n" );
146 * Load a dynamically linked library using a system dependent method.
148 * \param p_this vlc object
149 * \param psz_file library file
150 * \param p_handle the module handle returned
151 * \return 0 on success as well as the module handle.
153 int module_Load( vlc_object_t *p_this, const char *psz_file,
154 module_handle_t *p_handle )
156 module_handle_t handle;
158 #if defined(HAVE_DL_DYLD)
159 NSObjectFileImage image;
160 NSObjectFileImageReturnCode ret;
162 ret = NSCreateObjectFileImageFromFile( psz_file, &image );
164 if( ret != NSObjectFileImageSuccess )
166 msg_Warn( p_this, "cannot create image from `%s'", psz_file );
170 /* Open the dynamic module */
171 handle = NSLinkModule( image, psz_file,
172 NSLINKMODULE_OPTION_RETURN_ON_ERROR );
176 NSLinkEditErrors errors;
177 const char *psz_file, *psz_err;
179 NSLinkEditError( &errors, &i_errnum, &psz_file, &psz_err );
180 msg_Warn( p_this, "cannot link module `%s' (%s)", psz_file, psz_err );
181 NSDestroyObjectFileImage( image );
185 /* Destroy our image, we won't need it */
186 NSDestroyObjectFileImage( image );
188 #elif defined(HAVE_DL_BEOS)
189 handle = load_add_on( psz_file );
192 msg_Warn( p_this, "cannot load module `%s'", psz_file );
196 #elif defined(HAVE_DL_WINDOWS)
197 wchar_t psz_wfile[MAX_PATH];
198 MultiByteToWideChar( CP_ACP, 0, psz_file, -1, psz_wfile, MAX_PATH );
201 /* FIXME: this is not thread-safe -- Courmisch */
202 UINT mode = SetErrorMode (SEM_FAILCRITICALERRORS);
203 SetErrorMode (mode|SEM_FAILCRITICALERRORS);
206 handle = LoadLibraryW( psz_wfile );
214 char *psz_err = GetWindowsError();
215 msg_Warn( p_this, "cannot load module `%s' (%s)", psz_file, psz_err );
220 #elif defined(HAVE_DL_DLOPEN)
221 # if defined (RTLD_NOLOAD)
222 static pthread_once_t once = PTHREAD_ONCE_INIT;
223 pthread_once( &once, &load_libvlccore );
226 # if defined (RTLD_NOW)
227 const int flags = RTLD_NOW;
228 # elif defined (DL_LAZY)
229 const int flags = DL_LAZY;
234 handle = dlopen( psz_file, flags );
237 msg_Warn( p_this, "cannot load module `%s' (%s)",
238 psz_file, dlerror() );
242 #elif defined(HAVE_DL_SHL_LOAD)
243 handle = shl_load( psz_file, BIND_IMMEDIATE | BIND_NONFATAL, NULL );
246 msg_Warn( p_this, "cannot load module `%s' (%m)", psz_file );
251 # error "Something is wrong in modules.c"
260 * CloseModule: unload a dynamic library
262 * This function unloads a previously opened dynamically linked library
263 * using a system dependent method. No return value is taken in consideration,
264 * since some libraries sometimes refuse to close properly.
265 * \param handle handle of the library
268 void module_Unload( module_handle_t handle )
270 #if defined(HAVE_DL_DYLD)
271 NSUnLinkModule( handle, FALSE );
273 #elif defined(HAVE_DL_BEOS)
274 unload_add_on( handle );
276 #elif defined(HAVE_DL_WINDOWS)
277 FreeLibrary( handle );
279 #elif defined(HAVE_DL_DLOPEN)
280 # ifdef HAVE_VALGRIND_VALGRIND_H
281 if( RUNNING_ON_VALGRIND > 0 )
282 return; /* do not dlclose() so that we get proper stack traces */
286 #elif defined(HAVE_DL_SHL_LOAD)
287 shl_unload( handle );
294 * Looks up a symbol from a dynamically loaded library
296 * This function queries a loaded library for a symbol specified in a
297 * string, and returns a pointer to it. We don't check for dlerror() or
298 * similar functions, since we want a non-NULL symbol anyway.
300 * @param handle handle to the module
301 * @param psz_function function name
302 * @return NULL on error, or the address of the symbol
304 static void *module_Lookup( module_handle_t handle, const char *psz_function )
306 #if defined(HAVE_DL_DYLD)
307 char psz_call[strlen( psz_function ) + 2];
309 memcpy( psz_call + 1, psz_function, sizeof( psz_call ) - 1 );
311 NSSymbol sym = NSLookupSymbolInModule( handle, psz_call );
312 return NSAddressOfSymbol( sym );
314 #elif defined(HAVE_DL_BEOS)
316 if( B_OK == get_image_symbol( handle, psz_function,
317 B_SYMBOL_TYPE_TEXT, &p_symbol ) )
326 #elif defined(HAVE_DL_WINDOWS) && defined(UNDER_CE)
327 wchar_t wide[strlen( psz_function ) + 1];
330 wide[i] = psz_function[i]; /* UTF-16 <- ASCII */
331 while( psz_function[i++] );
333 return (void *)GetProcAddress( handle, wide );
335 #elif defined(HAVE_DL_WINDOWS) && defined(WIN32)
336 return (void *)GetProcAddress( handle, (char *)psz_function );
338 #elif defined(HAVE_DL_DLOPEN)
339 return dlsym( handle, psz_function );
341 #elif defined(HAVE_DL_SHL_LOAD)
343 shl_findsym( &handle, psz_function, TYPE_UNDEFINED, &p_sym );
349 #if defined(HAVE_DL_WINDOWS)
350 static char * GetWindowsError( void )
352 #if defined(UNDER_CE)
353 wchar_t psz_tmp[MAX_PATH];
354 char * psz_buffer = malloc( MAX_PATH );
356 char * psz_tmp = malloc( MAX_PATH );
358 int i = 0, i_error = GetLastError();
360 FormatMessage( FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
361 NULL, i_error, MAKELANGID (LANG_NEUTRAL, SUBLANG_DEFAULT),
362 (LPTSTR)psz_tmp, MAX_PATH, NULL );
364 /* Go to the end of the string */
365 while( psz_tmp[i] && psz_tmp[i] != _T('\r') && psz_tmp[i] != _T('\n') )
372 #if defined(UNDER_CE)
373 swprintf( psz_tmp + i, L" (error %i)", i_error );
374 psz_tmp[ 255 ] = L'\0';
376 snprintf( psz_tmp + i, 256 - i, " (error %i)", i_error );
377 psz_tmp[ 255 ] = '\0';
381 #if defined(UNDER_CE)
382 wcstombs( psz_buffer, psz_tmp, MAX_PATH );
388 #endif /* HAVE_DL_WINDOWS */
389 #endif /* HAVE_DYNAMIC_PLUGINS */