1 /* GMODULE - GLIB wrapper code for dynamic module loading
2 * Copyright (C) 1998 Tim Janik
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
14 * You should have received a copy of the GNU Library General Public
15 * License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
17 * Boston, MA 02111-1307, USA.
25 #include "gmoduleconf.h"
30 /* We maintain a list of modules, so we can reference count them.
31 * That's needed because some platforms don't support refernce counts on
32 * modules e.g. the shl_* implementation of HP-UX
33 * (http://www.stat.umn.edu/~luke/xls/projects/dlbasics/dlbasics.html).
34 * Also, the module for the program itself is kept seperatedly for
35 * faster access and because it has special semantics.
39 /* --- structures --- */
45 guint is_resident : 1;
51 /* --- prototypes --- */
52 static gpointer _g_module_open (const gchar *file_name,
54 static void _g_module_close (gpointer handle,
56 static gpointer _g_module_self (void);
57 static gpointer _g_module_symbol (gpointer handle,
58 const gchar *symbol_name);
59 static gchar* _g_module_build_path (const gchar *directory,
60 const gchar *module_name);
61 static inline void g_module_set_error (const gchar *error);
62 static inline GModule* g_module_find_by_handle (gpointer handle);
63 static inline GModule* g_module_find_by_name (const gchar *name);
66 /* --- variables --- */
67 G_LOCK_DEFINE_STATIC (GModule);
68 const char *g_log_domain_gmodule = "GModule";
69 static GModule *modules = NULL;
70 static GModule *main_module = NULL;
71 static GStaticPrivate module_error_private = G_STATIC_PRIVATE_INIT;
74 /* --- inline functions --- */
75 static inline GModule*
76 g_module_find_by_handle (gpointer handle)
79 GModule *retval = NULL;
82 if (main_module && main_module->handle == handle)
85 for (module = modules; module; module = module->next)
86 if (handle == module->handle)
96 static inline GModule*
97 g_module_find_by_name (const gchar *name)
100 GModule *retval = NULL;
103 for (module = modules; module; module = module->next)
104 if (strcmp (name, module->file_name) == 0)
115 g_module_set_error (const gchar *error)
117 g_static_private_set (&module_error_private, g_strdup (error), g_free);
122 /* --- include platform specifc code --- */
123 #define CHECK_ERROR(rv) { g_module_set_error (NULL); }
124 #if (G_MODULE_IMPL == G_MODULE_IMPL_DL)
125 #include "gmodule-dl.c"
126 #elif (G_MODULE_IMPL == G_MODULE_IMPL_DLD)
127 #include "gmodule-dld.c"
128 #elif (G_MODULE_IMPL == G_MODULE_IMPL_WIN32)
129 #include "gmodule-win32.c"
132 #define CHECK_ERROR(rv) { g_module_set_error ("dynamic modules are " \
133 "not supported by this system"); return rv; }
135 _g_module_open (const gchar *file_name,
141 _g_module_close (gpointer handle,
146 _g_module_self (void)
151 _g_module_symbol (gpointer handle,
152 const gchar *symbol_name)
157 _g_module_build_path (const gchar *directory,
158 const gchar *module_name)
162 #endif /* no implementation */
164 #if defined (NATIVE_WIN32) && defined (__LCC__)
166 LibMain (void *hinstDll,
167 unsigned long dwReason,
172 #endif /* NATIVE_WIN32 && __LCC__ */
175 /* --- functions --- */
177 g_module_supported (void)
185 g_module_open (const gchar *file_name,
198 handle = _g_module_self ();
201 main_module = g_new (GModule, 1);
202 main_module->file_name = NULL;
203 main_module->handle = handle;
204 main_module->ref_count = 1;
205 main_module->is_resident = TRUE;
206 main_module->unload = NULL;
207 main_module->next = NULL;
215 /* we first search the module list by name */
216 module = g_module_find_by_name (file_name);
224 /* open the module */
225 handle = _g_module_open (file_name, (flags & G_MODULE_BIND_LAZY) != 0);
229 GModuleCheckInit check_init;
230 const gchar *check_failed = NULL;
232 /* search the module list by handle, since file names are not unique */
233 module = g_module_find_by_handle (handle);
236 _g_module_close (module->handle, TRUE);
238 g_module_set_error (NULL);
243 saved_error = g_strdup (g_module_error ());
244 g_module_set_error (NULL);
246 module = g_new (GModule, 1);
247 module->file_name = g_strdup (file_name);
248 module->handle = handle;
249 module->ref_count = 1;
250 module->is_resident = FALSE;
251 module->unload = NULL;
253 module->next = modules;
257 /* check initialization */
258 if (g_module_symbol (module, "g_module_check_init", (gpointer) &check_init))
259 check_failed = check_init (module);
261 /* we don't call unload() if the initialization check failed. */
263 g_module_symbol (module, "g_module_unload", (gpointer) &module->unload);
269 error = g_strconcat ("GModule initialization check failed: ", check_failed, NULL);
270 g_module_close (module);
272 g_module_set_error (error);
276 g_module_set_error (saved_error);
278 g_free (saved_error);
285 g_module_close (GModule *module)
289 g_return_val_if_fail (module != NULL, FALSE);
290 g_return_val_if_fail (module->ref_count > 0, FALSE);
294 if (!module->ref_count && !module->is_resident && module->unload)
296 GModuleUnload unload;
298 unload = module->unload;
299 module->unload = NULL;
303 if (!module->ref_count && !module->is_resident)
317 last->next = node->next;
319 modules = node->next;
328 _g_module_close (module->handle, FALSE);
329 g_free (module->file_name);
334 return g_module_error() == NULL;
338 g_module_make_resident (GModule *module)
340 g_return_if_fail (module != NULL);
342 module->is_resident = TRUE;
346 g_module_error (void)
348 return g_static_private_get (&module_error_private);
352 g_module_symbol (GModule *module,
353 const gchar *symbol_name,
361 g_return_val_if_fail (module != NULL, FALSE);
362 g_return_val_if_fail (symbol_name != NULL, FALSE);
363 g_return_val_if_fail (symbol != NULL, FALSE);
365 #ifdef G_MODULE_NEED_USCORE
369 name = g_strconcat ("_", symbol_name, NULL);
370 *symbol = _g_module_symbol (module->handle, name);
373 #else /* !G_MODULE_NEED_USCORE */
374 *symbol = _g_module_symbol (module->handle, symbol_name);
375 #endif /* !G_MODULE_NEED_USCORE */
377 if ((module_error = g_module_error()))
381 error = g_strconcat ("`", symbol_name, "': ", module_error, NULL);
382 g_module_set_error (error);
392 g_module_name (GModule *module)
394 g_return_val_if_fail (module != NULL, NULL);
396 if (module == main_module)
399 return module->file_name;
403 g_module_build_path (const gchar *directory,
404 const gchar *module_name)
406 g_return_val_if_fail (module_name != NULL, NULL);
408 return _g_module_build_path (directory, module_name);