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/.
40 static gboolean thread_system_already_initialized = FALSE;
41 static gint g_thread_priority_map [G_THREAD_PRIORITY_URGENT];
43 #include G_THREAD_SOURCE
45 #ifndef PRIORITY_LOW_VALUE
46 # define PRIORITY_LOW_VALUE 0
49 #ifndef PRIORITY_URGENT_VALUE
50 # define PRIORITY_URGENT_VALUE 0
53 #ifndef PRIORITY_NORMAL_VALUE
54 # define PRIORITY_NORMAL_VALUE \
55 PRIORITY_LOW_VALUE + (PRIORITY_URGENT_VALUE - PRIORITY_LOW_VALUE) * 40 / 100
56 #endif /* PRIORITY_NORMAL_VALUE */
58 #ifndef PRIORITY_HIGH_VALUE
59 # define PRIORITY_HIGH_VALUE \
60 PRIORITY_LOW_VALUE + (PRIORITY_URGENT_VALUE - PRIORITY_LOW_VALUE) * 80 / 100
61 #endif /* PRIORITY_HIGH_VALUE */
63 void g_mutex_init (void);
64 void g_mem_init (void);
65 void g_messages_init (void);
67 #define G_MUTEX_DEBUG_INFO(mutex) (*((gpointer*)(((char*)mutex)+G_MUTEX_SIZE)))
69 typedef struct _ErrorCheckInfo ErrorCheckInfo;
70 struct _ErrorCheckInfo
77 g_mutex_new_errorcheck_impl (void)
79 GMutex *retval = g_thread_functions_for_glib_use_default.mutex_new ();
80 retval = g_realloc (retval, G_MUTEX_SIZE + sizeof (gpointer));
81 G_MUTEX_DEBUG_INFO (retval) = NULL;
86 g_mutex_lock_errorcheck_impl (GMutex *mutex,
91 GThread *self = g_thread_self ();
93 if (magic != G_MUTEX_DEBUG_MAGIC)
96 if (G_MUTEX_DEBUG_INFO (mutex) == NULL)
98 /* if the debug info is NULL, we have not yet locked that mutex,
100 g_thread_functions_for_glib_use_default.mutex_lock (mutex);
101 /* Now we have to check again, because another thread might have
102 * tried to lock the mutex at the same time we did. This
103 * technique is not 100% save on systems without decent cache
104 * coherence, but we have no choice */
105 if (G_MUTEX_DEBUG_INFO (mutex) == NULL)
107 info = G_MUTEX_DEBUG_INFO (mutex) = g_new0 (ErrorCheckInfo, 1);
109 g_thread_functions_for_glib_use_default.mutex_unlock (mutex);
112 info = G_MUTEX_DEBUG_INFO (mutex);
113 if (info->owner == self)
114 g_error ("Trying to recursivly lock a mutex at '%s', "
115 "previously locked at '%s'",
116 location, info->location);
118 g_thread_functions_for_glib_use_default.mutex_lock (mutex);
121 info->location = location;
125 g_mutex_trylock_errorcheck_impl (GMutex *mutex,
129 ErrorCheckInfo *info = G_MUTEX_DEBUG_INFO (mutex);
130 GThread *self = g_thread_self ();
132 if (magic != G_MUTEX_DEBUG_MAGIC)
133 location = "unknown";
137 /* This mutex has not yet been used, so simply lock and return TRUE */
138 g_mutex_lock_errorcheck_impl (mutex, magic, location);
142 if (info->owner == self)
143 g_error ("Trying to recursivly lock a mutex at '%s', "
144 "previously locked at '%s'",
145 location, info->location);
147 if (!g_thread_functions_for_glib_use_default.mutex_trylock (mutex))
151 info->location = location;
157 g_mutex_unlock_errorcheck_impl (GMutex *mutex,
161 ErrorCheckInfo *info = G_MUTEX_DEBUG_INFO (mutex);
162 GThread *self = g_thread_self ();
164 if (magic != G_MUTEX_DEBUG_MAGIC)
165 location = "unknown";
167 if (!info || info->owner == NULL)
168 g_error ("Trying to unlock an unlocked mutex at '%s'", location);
170 if (info->owner != self)
171 g_warning ("Trying to unlock a mutex at '%s', "
172 "previously locked by a different thread at '%s'",
173 location, info->location);
176 info->location = NULL;
178 g_thread_functions_for_glib_use_default.mutex_unlock (mutex);
182 g_mutex_free_errorcheck_impl (GMutex *mutex)
184 g_free (G_MUTEX_DEBUG_INFO (mutex));
185 g_thread_functions_for_glib_use_default.mutex_free (mutex);
189 g_cond_wait_errorcheck_impl (GCond *cond,
195 ErrorCheckInfo *info = G_MUTEX_DEBUG_INFO (mutex);
196 GThread *self = g_thread_self ();
198 if (magic != G_MUTEX_DEBUG_MAGIC)
199 location = "unknown";
201 if (!info || info->owner == NULL)
202 g_error ("Trying to use an unlocked mutex in g_cond_wait() at '%s'",
205 if (info->owner != self)
206 g_error ("Trying to use a mutex locked by another thread in "
207 "g_cond_wait() at '%s'", location);
210 location = info->location;
212 g_thread_functions_for_glib_use_default.cond_wait (cond, mutex);
215 info->location = location;
220 g_cond_timed_wait_errorcheck_impl (GCond *cond,
226 ErrorCheckInfo *info = G_MUTEX_DEBUG_INFO (mutex);
227 GThread *self = g_thread_self ();
230 if (magic != G_MUTEX_DEBUG_MAGIC)
231 location = "unknown";
233 if (!info || info->owner == NULL)
234 g_error ("Trying to use an unlocked mutex in g_cond_timed_wait() at '%s'",
237 if (info->owner != self)
238 g_error ("Trying to use a mutex locked by another thread in "
239 "g_cond_timed_wait() at '%s'", location);
242 location = info->location;
244 retval = g_thread_functions_for_glib_use_default.cond_timed_wait (cond,
249 info->location = location;
255 /* unshadow function declaration. See glib.h */
259 g_thread_init_with_errorcheck_mutexes (GThreadFunctions* init)
261 GThreadFunctions errorcheck_functions;
263 g_error ("Errorcheck mutexes can only be used for native "
264 "thread implementations. Sorry." );
265 errorcheck_functions = g_thread_functions_for_glib_use_default;
266 errorcheck_functions.mutex_new = g_mutex_new_errorcheck_impl;
267 errorcheck_functions.mutex_lock =
268 (void (*)(GMutex *)) g_mutex_lock_errorcheck_impl;
269 errorcheck_functions.mutex_trylock =
270 (gboolean (*)(GMutex *)) g_mutex_trylock_errorcheck_impl;
271 errorcheck_functions.mutex_unlock =
272 (void (*)(GMutex *)) g_mutex_unlock_errorcheck_impl;
273 errorcheck_functions.mutex_free = g_mutex_free_errorcheck_impl;
274 errorcheck_functions.cond_wait = g_cond_wait_errorcheck_impl;
275 errorcheck_functions.cond_timed_wait = g_cond_timed_wait_errorcheck_impl;
277 g_thread_init (&errorcheck_functions);
281 g_thread_init (GThreadFunctions* init)
285 #ifndef G_THREADS_ENABLED
286 g_error ("GLib thread support is disabled.");
287 #endif /* !G_THREADS_ENABLED */
289 if (thread_system_already_initialized)
290 g_error ("GThread system may only be initialized once.");
292 thread_system_already_initialized = TRUE;
295 init = &g_thread_functions_for_glib_use_default;
297 g_thread_use_default_impl = FALSE;
299 #if defined (G_OS_WIN32) && defined (__GNUC__)
300 memcpy(&g_thread_functions_for_glib_use, init, sizeof (*init));
302 g_thread_functions_for_glib_use = *init;
304 /* It is important, that g_threads_got_initialized is not set before the
305 * thread initialization functions of the different modules are called
308 supported = (init->mutex_new &&
310 init->mutex_trylock &&
311 init->mutex_unlock &&
315 init->cond_broadcast &&
317 init->cond_timed_wait &&
323 /* if somebody is calling g_thread_init (), it means that he wants to
324 * have thread support, so check this
328 if (g_thread_use_default_impl)
329 g_error ("Threads are not supported on this platform.");
331 g_error ("The supplied thread function vector is invalid.");
334 /* now do any initialization stuff required by the implementation,
335 * but only if called with a NULL argument, of course. Otherwise
336 * it's up to the user to do so. */
338 #ifdef HAVE_G_THREAD_IMPL_INIT
339 if (g_thread_use_default_impl)
340 g_thread_impl_init();
343 g_thread_priority_map [G_THREAD_PRIORITY_LOW] = PRIORITY_LOW_VALUE;
344 g_thread_priority_map [G_THREAD_PRIORITY_NORMAL] = PRIORITY_NORMAL_VALUE;
345 g_thread_priority_map [G_THREAD_PRIORITY_HIGH] = PRIORITY_HIGH_VALUE;
346 g_thread_priority_map [G_THREAD_PRIORITY_URGENT] = PRIORITY_URGENT_VALUE;
348 /* now call the thread initialization functions of the different
349 * glib modules. order does matter, g_mutex_init MUST come first.
355 /* now we can set g_threads_got_initialized and thus enable
356 * all the thread functions
358 g_threads_got_initialized = TRUE;
360 /* we want the main thread to run with normal priority */
361 g_thread_set_priority (g_thread_self(), G_THREAD_PRIORITY_NORMAL);