1 /* GLIB - Library of useful routines for C programming
2 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
4 * gthread.c: thread related functions
5 * Copyright 1998 Sebastian Wilhelmi; University of Karlsruhe
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with this library; if not, write to the
19 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 * Boston, MA 02111-1307, USA.
24 * Modified by the GLib Team and others 1997-2000. See the AUTHORS
25 * file for a list of people on the GLib Team. See the ChangeLog
26 * files for a list of changes. These files are distributed with
27 * GLib at ftp://ftp.gtk.org/pub/gtk/.
37 #include "gthreadinit.h"
39 #ifdef G_THREADS_ENABLED
41 static gboolean thread_system_already_initialized = FALSE;
42 static gint g_thread_priority_map [G_THREAD_PRIORITY_URGENT + 1];
44 #include G_THREAD_SOURCE
46 #ifndef PRIORITY_LOW_VALUE
47 # define PRIORITY_LOW_VALUE 0
50 #ifndef PRIORITY_URGENT_VALUE
51 # define PRIORITY_URGENT_VALUE 0
54 #ifndef PRIORITY_NORMAL_VALUE
55 # define PRIORITY_NORMAL_VALUE \
56 ((PRIORITY_LOW_VALUE * 6 + PRIORITY_URGENT_VALUE * 4) / 10)
57 #endif /* PRIORITY_NORMAL_VALUE */
59 #ifndef PRIORITY_HIGH_VALUE
60 # define PRIORITY_HIGH_VALUE \
61 ((PRIORITY_NORMAL_VALUE + PRIORITY_URGENT_VALUE * 2) / 3)
62 #endif /* PRIORITY_HIGH_VALUE */
64 void g_mutex_init (void);
65 void g_mem_init (void);
66 void g_messages_init (void);
67 void g_convert_init (void);
68 void g_rand_init (void);
69 void g_main_thread_init (void);
71 #define G_MUTEX_DEBUG_INFO(mutex) (*((gpointer*)(((char*)mutex)+G_MUTEX_SIZE)))
73 typedef struct _ErrorCheckInfo ErrorCheckInfo;
74 struct _ErrorCheckInfo
81 g_mutex_new_errorcheck_impl (void)
83 GMutex *retval = g_thread_functions_for_glib_use_default.mutex_new ();
84 retval = g_realloc (retval, G_MUTEX_SIZE + sizeof (gpointer));
85 G_MUTEX_DEBUG_INFO (retval) = NULL;
90 g_mutex_lock_errorcheck_impl (GMutex *mutex,
95 GThread *self = g_thread_self ();
97 if (magic != G_MUTEX_DEBUG_MAGIC)
100 if (G_MUTEX_DEBUG_INFO (mutex) == NULL)
102 /* if the debug info is NULL, we have not yet locked that mutex,
104 g_thread_functions_for_glib_use_default.mutex_lock (mutex);
105 /* Now we have to check again, because another thread might have
106 * tried to lock the mutex at the same time we did. This
107 * technique is not 100% save on systems without decent cache
108 * coherence, but we have no choice */
109 if (G_MUTEX_DEBUG_INFO (mutex) == NULL)
111 info = G_MUTEX_DEBUG_INFO (mutex) = g_new0 (ErrorCheckInfo, 1);
113 g_thread_functions_for_glib_use_default.mutex_unlock (mutex);
116 info = G_MUTEX_DEBUG_INFO (mutex);
117 if (info->owner == self)
118 g_error ("Trying to recursivly lock a mutex at '%s', "
119 "previously locked at '%s'",
120 location, info->location);
122 g_thread_functions_for_glib_use_default.mutex_lock (mutex);
125 info->location = location;
129 g_mutex_trylock_errorcheck_impl (GMutex *mutex,
133 ErrorCheckInfo *info = G_MUTEX_DEBUG_INFO (mutex);
134 GThread *self = g_thread_self ();
136 if (magic != G_MUTEX_DEBUG_MAGIC)
137 location = "unknown";
141 /* This mutex has not yet been used, so simply lock and return TRUE */
142 g_mutex_lock_errorcheck_impl (mutex, magic, location);
146 if (info->owner == self)
147 g_error ("Trying to recursivly lock a mutex at '%s', "
148 "previously locked at '%s'",
149 location, info->location);
151 if (!g_thread_functions_for_glib_use_default.mutex_trylock (mutex))
155 info->location = location;
161 g_mutex_unlock_errorcheck_impl (GMutex *mutex,
165 ErrorCheckInfo *info = G_MUTEX_DEBUG_INFO (mutex);
166 GThread *self = g_thread_self ();
168 if (magic != G_MUTEX_DEBUG_MAGIC)
169 location = "unknown";
171 if (!info || info->owner == NULL)
172 g_error ("Trying to unlock an unlocked mutex at '%s'", location);
174 if (info->owner != self)
175 g_warning ("Trying to unlock a mutex at '%s', "
176 "previously locked by a different thread at '%s'",
177 location, info->location);
180 info->location = NULL;
182 g_thread_functions_for_glib_use_default.mutex_unlock (mutex);
186 g_mutex_free_errorcheck_impl (GMutex *mutex,
190 ErrorCheckInfo *info = G_MUTEX_DEBUG_INFO (mutex);
192 if (magic != G_MUTEX_DEBUG_MAGIC)
193 location = "unknown";
195 if (info && info->owner != NULL)
196 g_error ("Trying to free a locked mutex at '%s', "
197 "which was previously locked at '%s'",
198 location, info->location);
200 g_free (G_MUTEX_DEBUG_INFO (mutex));
201 g_thread_functions_for_glib_use_default.mutex_free (mutex);
205 g_cond_wait_errorcheck_impl (GCond *cond,
211 ErrorCheckInfo *info = G_MUTEX_DEBUG_INFO (mutex);
212 GThread *self = g_thread_self ();
214 if (magic != G_MUTEX_DEBUG_MAGIC)
215 location = "unknown";
217 if (!info || info->owner == NULL)
218 g_error ("Trying to use an unlocked mutex in g_cond_wait() at '%s'",
221 if (info->owner != self)
222 g_error ("Trying to use a mutex locked by another thread in "
223 "g_cond_wait() at '%s'", location);
226 location = info->location;
228 g_thread_functions_for_glib_use_default.cond_wait (cond, mutex);
231 info->location = location;
236 g_cond_timed_wait_errorcheck_impl (GCond *cond,
242 ErrorCheckInfo *info = G_MUTEX_DEBUG_INFO (mutex);
243 GThread *self = g_thread_self ();
246 if (magic != G_MUTEX_DEBUG_MAGIC)
247 location = "unknown";
249 if (!info || info->owner == NULL)
250 g_error ("Trying to use an unlocked mutex in g_cond_timed_wait() at '%s'",
253 if (info->owner != self)
254 g_error ("Trying to use a mutex locked by another thread in "
255 "g_cond_timed_wait() at '%s'", location);
258 location = info->location;
260 retval = g_thread_functions_for_glib_use_default.cond_timed_wait (cond,
265 info->location = location;
271 /* unshadow function declaration. See gthread.h */
275 g_thread_init_with_errorcheck_mutexes (GThreadFunctions* init)
277 GThreadFunctions errorcheck_functions;
279 g_error ("Errorcheck mutexes can only be used for native "
280 "thread implementations. Sorry." );
282 #ifdef HAVE_G_THREAD_IMPL_INIT
283 /* This isn't called in g_thread_init, as it doesn't think to get
284 * the default implementation, so we have to call it on our own.
286 * We must call this before copying
287 * g_thread_functions_for_glib_use_default as the
288 * implementation-specific init function might modify the contents
289 * of g_thread_functions_for_glib_use_default based on operating
290 * system version, C library version, or whatever. */
291 g_thread_impl_init();
292 #endif /* HAVE_G_THREAD_IMPL_INIT */
294 errorcheck_functions = g_thread_functions_for_glib_use_default;
295 errorcheck_functions.mutex_new = g_mutex_new_errorcheck_impl;
296 errorcheck_functions.mutex_lock =
297 (void (*)(GMutex *)) g_mutex_lock_errorcheck_impl;
298 errorcheck_functions.mutex_trylock =
299 (gboolean (*)(GMutex *)) g_mutex_trylock_errorcheck_impl;
300 errorcheck_functions.mutex_unlock =
301 (void (*)(GMutex *)) g_mutex_unlock_errorcheck_impl;
302 errorcheck_functions.mutex_free =
303 (void (*)(GMutex *)) g_mutex_free_errorcheck_impl;
304 errorcheck_functions.cond_wait =
305 (void (*)(GCond *, GMutex *)) g_cond_wait_errorcheck_impl;
306 errorcheck_functions.cond_timed_wait =
307 (gboolean (*)(GCond *, GMutex *, GTimeVal *))
308 g_cond_timed_wait_errorcheck_impl;
310 g_thread_init (&errorcheck_functions);
314 g_thread_init (GThreadFunctions* init)
318 if (thread_system_already_initialized)
319 g_error ("GThread system may only be initialized once.");
321 thread_system_already_initialized = TRUE;
325 #ifdef HAVE_G_THREAD_IMPL_INIT
326 /* now do any initialization stuff required by the
327 * implementation, but only if called with a NULL argument, of
328 * course. Otherwise it's up to the user to do so. */
329 g_thread_impl_init();
330 #endif /* HAVE_G_THREAD_IMPL_INIT */
331 init = &g_thread_functions_for_glib_use_default;
334 g_thread_use_default_impl = FALSE;
336 g_thread_functions_for_glib_use = *init;
338 supported = (init->mutex_new &&
340 init->mutex_trylock &&
341 init->mutex_unlock &&
345 init->cond_broadcast &&
347 init->cond_timed_wait &&
352 init->thread_create &&
353 init->thread_yield &&
356 init->thread_set_priority &&
359 /* if somebody is calling g_thread_init (), it means that he wants to
360 * have thread support, so check this
364 if (g_thread_use_default_impl)
365 g_error ("Threads are not supported on this platform.");
367 g_error ("The supplied thread function vector is invalid.");
370 g_thread_priority_map [G_THREAD_PRIORITY_LOW] = PRIORITY_LOW_VALUE;
371 g_thread_priority_map [G_THREAD_PRIORITY_NORMAL] = PRIORITY_NORMAL_VALUE;
372 g_thread_priority_map [G_THREAD_PRIORITY_HIGH] = PRIORITY_HIGH_VALUE;
373 g_thread_priority_map [G_THREAD_PRIORITY_URGENT] = PRIORITY_URGENT_VALUE;
375 g_thread_init_glib ();
378 #else /* !G_THREADS_ENABLED */
381 g_thread_init (GThreadFunctions* init)
383 g_error ("GLib thread support is disabled.");
386 #endif /* !G_THREADS_ENABLED */