-/* -*- mode: C; c-file-style: "gnu" -*- */
+/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
/* dbus-threads.h D-Bus threads handling
*
* Copyright (C) 2002, 2003, 2006 Red Hat Inc.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
+#include <config.h>
#include "dbus-threads.h"
#include "dbus-internals.h"
#include "dbus-threads-internal.h"
#include "dbus-list.h"
-static DBusThreadFunctions thread_functions =
-{
- 0,
- NULL, NULL, NULL, NULL, NULL,
- NULL, NULL, NULL, NULL, NULL,
- NULL, NULL, NULL, NULL,
-
- NULL, NULL, NULL, NULL
-};
-
static int thread_init_generation = 0;
-
-static DBusList *uninitialized_mutex_list = NULL;
-static DBusList *uninitialized_condvar_list = NULL;
-
-/** This is used for the no-op default mutex pointer, just to be distinct from #NULL */
-#define _DBUS_DUMMY_MUTEX ((DBusMutex*)0xABCDEF)
-
-/** This is used for the no-op default mutex pointer, just to be distinct from #NULL */
-#define _DBUS_DUMMY_CONDVAR ((DBusCondVar*)0xABCDEF2)
/**
* @defgroup DBusThreadsInternals Thread functions
* @ingroup DBusInternals
- * @brief _dbus_mutex_lock(), etc.
+ * @brief _dbus_rmutex_lock(), etc.
*
* Functions and macros related to threads and thread locks.
*
*/
/**
- * Creates a new mutex using the function supplied to dbus_threads_init(),
+ * Creates a new mutex
* or creates a no-op mutex if threads are not initialized.
* May return #NULL even if threads are initialized, indicating
* out-of-memory.
*
- * @returns new mutex or #NULL
+ * If possible, the mutex returned by this function is recursive, to
+ * avoid deadlocks. However, that cannot be relied on.
+ *
+ * @param location_p the location of the new mutex, can return #NULL on OOM
*/
-DBusMutex*
-_dbus_mutex_new (void)
+void
+_dbus_rmutex_new_at_location (DBusRMutex **location_p)
{
- if (thread_functions.recursive_mutex_new)
- return (* thread_functions.recursive_mutex_new) ();
- else if (thread_functions.mutex_new)
- return (* thread_functions.mutex_new) ();
- else
- return _DBUS_DUMMY_MUTEX;
+ _dbus_assert (location_p != NULL);
+
+ if (!dbus_threads_init_default ())
+ {
+ *location_p = NULL;
+ return;
+ }
+
+ *location_p = _dbus_platform_rmutex_new ();
}
/**
- * This does the same thing as _dbus_mutex_new. It however
- * gives another level of indirection by allocating a pointer
- * to point to the mutex location. This allows the threading
- * module to swap out dummy mutexes for real a real mutex so libraries
- * can initialize threads even after the D-Bus API has been used.
+ * Creates a new mutex
+ * or creates a no-op mutex if threads are not initialized.
+ * May return #NULL even if threads are initialized, indicating
+ * out-of-memory.
+ *
+ * The returned mutex is suitable for use with condition variables.
*
* @param location_p the location of the new mutex, can return #NULL on OOM
*/
void
-_dbus_mutex_new_at_location (DBusMutex **location_p)
+_dbus_cmutex_new_at_location (DBusCMutex **location_p)
{
_dbus_assert (location_p != NULL);
- *location_p = _dbus_mutex_new();
-
- if (thread_init_generation != _dbus_current_generation && *location_p)
+ if (!dbus_threads_init_default ())
{
- if (!_dbus_list_append (&uninitialized_mutex_list, location_p))
- {
- _dbus_mutex_free (*location_p);
- *location_p = NULL;
- }
+ *location_p = NULL;
+ return;
}
+
+ *location_p = _dbus_platform_cmutex_new ();
}
/**
- * Frees a mutex created with dbus_mutex_new(); does
- * nothing if passed a #NULL pointer.
+ * Frees a DBusRMutex; does nothing if passed a #NULL pointer.
*/
void
-_dbus_mutex_free (DBusMutex *mutex)
+_dbus_rmutex_free_at_location (DBusRMutex **location_p)
{
- if (mutex)
- {
- if (mutex && thread_functions.recursive_mutex_free)
- (* thread_functions.recursive_mutex_free) (mutex);
- else if (mutex && thread_functions.mutex_free)
- (* thread_functions.mutex_free) (mutex);
- }
+ if (location_p == NULL)
+ return;
+
+ if (*location_p != NULL)
+ _dbus_platform_rmutex_free (*location_p);
}
/**
- * Frees a mutex and removes it from the
- * uninitialized_mutex_list;
- * does nothing if passed a #NULL pointer.
+ * Frees a DBusCMutex; does nothing if passed a #NULL pointer.
*/
void
-_dbus_mutex_free_at_location (DBusMutex **location_p)
+_dbus_cmutex_free_at_location (DBusCMutex **location_p)
{
- if (location_p)
- {
- if (thread_init_generation != _dbus_current_generation)
- _dbus_list_remove (&uninitialized_mutex_list, location_p);
+ if (location_p == NULL)
+ return;
- _dbus_mutex_free (*location_p);
- }
+ if (*location_p != NULL)
+ _dbus_platform_cmutex_free (*location_p);
}
/**
* recursive locks.
*/
void
-_dbus_mutex_lock (DBusMutex *mutex)
+_dbus_rmutex_lock (DBusRMutex *mutex)
{
- if (mutex)
- {
- if (thread_functions.recursive_mutex_lock)
- (* thread_functions.recursive_mutex_lock) (mutex);
- else if (thread_functions.mutex_lock)
- (* thread_functions.mutex_lock) (mutex);
- }
+ if (mutex == NULL)
+ return;
+
+ _dbus_platform_rmutex_lock (mutex);
+}
+
+/**
+ * Locks a mutex. Does nothing if passed a #NULL pointer.
+ * Locks may be recursive if threading implementation initialized
+ * recursive locks.
+ */
+void
+_dbus_cmutex_lock (DBusCMutex *mutex)
+{
+ if (mutex == NULL)
+ return;
+
+ _dbus_platform_cmutex_lock (mutex);
}
/**
* @returns #TRUE on success
*/
void
-_dbus_mutex_unlock (DBusMutex *mutex)
+_dbus_rmutex_unlock (DBusRMutex *mutex)
{
- if (mutex)
- {
- if (thread_functions.recursive_mutex_unlock)
- (* thread_functions.recursive_mutex_unlock) (mutex);
- else if (thread_functions.mutex_unlock)
- (* thread_functions.mutex_unlock) (mutex);
- }
+ if (mutex == NULL)
+ return;
+
+ _dbus_platform_rmutex_unlock (mutex);
+}
+
+/**
+ * Unlocks a mutex. Does nothing if passed a #NULL pointer.
+ *
+ * @returns #TRUE on success
+ */
+void
+_dbus_cmutex_unlock (DBusCMutex *mutex)
+{
+ if (mutex == NULL)
+ return;
+
+ _dbus_platform_cmutex_unlock (mutex);
}
/**
DBusCondVar *
_dbus_condvar_new (void)
{
- if (thread_functions.condvar_new)
- return (* thread_functions.condvar_new) ();
- else
- return _DBUS_DUMMY_CONDVAR;
+ if (!dbus_threads_init_default ())
+ return NULL;
+
+ return _dbus_platform_condvar_new ();
}
/**
* This does the same thing as _dbus_condvar_new. It however
* gives another level of indirection by allocating a pointer
- * to point to the condvar location. This allows the threading
- * module to swap out dummy condvars for real a real condvar so libraries
- * can initialize threads even after the D-Bus API has been used.
+ * to point to the condvar location; this used to be useful.
*
* @returns the location of a new condvar or #NULL on OOM
*/
void
_dbus_condvar_new_at_location (DBusCondVar **location_p)
{
- *location_p = _dbus_condvar_new();
+ _dbus_assert (location_p != NULL);
- if (thread_init_generation != _dbus_current_generation && *location_p)
- {
- if (!_dbus_list_append (&uninitialized_condvar_list, location_p))
- {
- _dbus_condvar_free (*location_p);
- *location_p = NULL;
- }
- }
+ *location_p = _dbus_condvar_new();
}
void
_dbus_condvar_free (DBusCondVar *cond)
{
- if (cond && thread_functions.condvar_free)
- (* thread_functions.condvar_free) (cond);
+ if (cond == NULL)
+ return;
+
+ _dbus_platform_condvar_free (cond);
}
/**
- * Frees a conditional variable and removes it from the
- * uninitialized_condvar_list;
- * does nothing if passed a #NULL pointer.
+ * Frees a condition variable; does nothing if passed a #NULL pointer.
*/
void
_dbus_condvar_free_at_location (DBusCondVar **location_p)
{
- if (location_p)
- {
- if (thread_init_generation != _dbus_current_generation)
- _dbus_list_remove (&uninitialized_condvar_list, location_p);
+ if (location_p == NULL)
+ return;
- _dbus_condvar_free (*location_p);
- }
+ if (*location_p != NULL)
+ _dbus_platform_condvar_free (*location_p);
}
/**
*/
void
_dbus_condvar_wait (DBusCondVar *cond,
- DBusMutex *mutex)
+ DBusCMutex *mutex)
{
- if (cond && mutex && thread_functions.condvar_wait)
- (* thread_functions.condvar_wait) (cond, mutex);
+ if (cond == NULL || mutex == NULL)
+ return;
+
+ _dbus_platform_condvar_wait (cond, mutex);
}
/**
*/
dbus_bool_t
_dbus_condvar_wait_timeout (DBusCondVar *cond,
- DBusMutex *mutex,
+ DBusCMutex *mutex,
int timeout_milliseconds)
{
- if (cond && mutex && thread_functions.condvar_wait)
- return (* thread_functions.condvar_wait_timeout) (cond, mutex, timeout_milliseconds);
- else
+ if (cond == NULL || mutex == NULL)
return TRUE;
+
+ return _dbus_platform_condvar_wait_timeout (cond, mutex,
+ timeout_milliseconds);
}
/**
void
_dbus_condvar_wake_one (DBusCondVar *cond)
{
- if (cond && thread_functions.condvar_wake_one)
- (* thread_functions.condvar_wake_one) (cond);
+ if (cond == NULL)
+ return;
+
+ _dbus_platform_condvar_wake_one (cond);
}
-/**
- * If there are threads waiting on the condition variable, wake
- * up all of them.
- * Does nothing if passed a #NULL pointer.
- */
-void
-_dbus_condvar_wake_all (DBusCondVar *cond)
+#ifdef DBUS_HAVE_STATIC_RECURSIVE_MUTEXES
+
+static dbus_bool_t
+init_global_locks (void)
{
- if (cond && thread_functions.condvar_wake_all)
- (* thread_functions.condvar_wake_all) (cond);
+ return TRUE;
}
+/* implementations in dbus-sysdeps-pthread.c */
+
+#else /* !defined(DBUS_HAVE_STATIC_RECURSIVE_MUTEXES) */
+
+static DBusRMutex *global_locks[_DBUS_N_GLOBAL_LOCKS] = { NULL };
+
static void
-shutdown_global_locks (void *data)
+shutdown_global_locks (void *nil)
{
- DBusMutex ***locks = data;
int i;
- i = 0;
- while (i < _DBUS_N_GLOBAL_LOCKS)
+ for (i = 0; i < _DBUS_N_GLOBAL_LOCKS; i++)
{
- _dbus_mutex_free (*(locks[i]));
- *(locks[i]) = NULL;
- ++i;
+ _dbus_assert (global_locks[i] != NULL);
+ _dbus_platform_rmutex_free (global_locks[i]);
+ global_locks[i] = NULL;
}
-
- dbus_free (locks);
-}
-
-static void
-shutdown_uninitialized_locks (void *data)
-{
- _dbus_list_clear (&uninitialized_mutex_list);
- _dbus_list_clear (&uninitialized_condvar_list);
}
static dbus_bool_t
-init_uninitialized_locks (void)
+init_global_locks (void)
{
- DBusList *link;
-
- _dbus_assert (thread_init_generation != _dbus_current_generation);
-
- link = uninitialized_mutex_list;
- while (link != NULL)
- {
- DBusMutex **mp;
-
- mp = (DBusMutex **)link->data;
- _dbus_assert (*mp == _DBUS_DUMMY_MUTEX);
-
- *mp = _dbus_mutex_new ();
- if (*mp == NULL)
- goto fail_mutex;
-
- link = _dbus_list_get_next_link (&uninitialized_mutex_list, link);
- }
+ int i;
+ dbus_bool_t ok;
- link = uninitialized_condvar_list;
- while (link != NULL)
+ for (i = 0; i < _DBUS_N_GLOBAL_LOCKS; i++)
{
- DBusCondVar **cp;
+ _dbus_assert (global_locks[i] == NULL);
- cp = (DBusCondVar **)link->data;
- _dbus_assert (*cp == _DBUS_DUMMY_CONDVAR);
+ global_locks[i] = _dbus_platform_rmutex_new ();
- *cp = _dbus_condvar_new ();
- if (*cp == NULL)
- goto fail_condvar;
-
- link = _dbus_list_get_next_link (&uninitialized_condvar_list, link);
+ if (global_locks[i] == NULL)
+ goto failed;
}
- _dbus_list_clear (&uninitialized_mutex_list);
- _dbus_list_clear (&uninitialized_condvar_list);
+ _dbus_platform_rmutex_lock (global_locks[_DBUS_LOCK_shutdown_funcs]);
+ ok = _dbus_register_shutdown_func_unlocked (shutdown_global_locks, NULL);
+ _dbus_platform_rmutex_unlock (global_locks[_DBUS_LOCK_shutdown_funcs]);
- if (!_dbus_register_shutdown_func (shutdown_uninitialized_locks,
- NULL))
- goto fail_condvar;
+ if (!ok)
+ goto failed;
return TRUE;
- fail_condvar:
- link = uninitialized_condvar_list;
- while (link != NULL)
+ failed:
+ for (i = i - 1; i >= 0; i--)
{
- DBusCondVar **cp;
-
- cp = (DBusCondVar **)link->data;
-
- if (*cp != _DBUS_DUMMY_CONDVAR)
- _dbus_condvar_free (*cp);
- else
- break;
-
- *cp = _DBUS_DUMMY_CONDVAR;
-
- link = _dbus_list_get_next_link (&uninitialized_condvar_list, link);
- }
-
- fail_mutex:
- link = uninitialized_mutex_list;
- while (link != NULL)
- {
- DBusMutex **mp;
-
- mp = (DBusMutex **)link->data;
-
- if (*mp != _DBUS_DUMMY_MUTEX)
- _dbus_mutex_free (*mp);
- else
- break;
-
- *mp = _DBUS_DUMMY_MUTEX;
-
- link = _dbus_list_get_next_link (&uninitialized_mutex_list, link);
+ _dbus_platform_rmutex_free (global_locks[i]);
+ global_locks[i] = NULL;
}
return FALSE;
}
-static dbus_bool_t
-init_locks (void)
+dbus_bool_t
+_dbus_lock (DBusGlobalLock lock)
{
- int i;
- DBusMutex ***dynamic_global_locks;
-
- DBusMutex **global_locks[] = {
-#define LOCK_ADDR(name) (& _dbus_lock_##name)
- LOCK_ADDR (win_fds),
- LOCK_ADDR (sid_atom_cache),
- LOCK_ADDR (list),
- LOCK_ADDR (connection_slots),
- LOCK_ADDR (pending_call_slots),
- LOCK_ADDR (server_slots),
- LOCK_ADDR (message_slots),
- LOCK_ADDR (atomic),
- LOCK_ADDR (bus),
- LOCK_ADDR (shutdown_funcs),
- LOCK_ADDR (system_users),
- LOCK_ADDR (message_cache),
- LOCK_ADDR (shared_connections),
- LOCK_ADDR (machine_uuid)
-#undef LOCK_ADDR
- };
-
- _dbus_assert (_DBUS_N_ELEMENTS (global_locks) ==
- _DBUS_N_GLOBAL_LOCKS);
-
- i = 0;
-
- dynamic_global_locks = dbus_new (DBusMutex**, _DBUS_N_GLOBAL_LOCKS);
- if (dynamic_global_locks == NULL)
- goto failed;
-
- while (i < _DBUS_N_ELEMENTS (global_locks))
- {
- *global_locks[i] = _dbus_mutex_new ();
-
- if (*global_locks[i] == NULL)
- goto failed;
+ _dbus_assert (lock >= 0);
+ _dbus_assert (lock < _DBUS_N_GLOBAL_LOCKS);
- dynamic_global_locks[i] = global_locks[i];
-
- ++i;
- }
-
- if (!_dbus_register_shutdown_func (shutdown_global_locks,
- dynamic_global_locks))
- goto failed;
+ if (thread_init_generation != _dbus_current_generation &&
+ !dbus_threads_init_default ())
+ return FALSE;
- if (!init_uninitialized_locks ())
- goto failed;
-
+ _dbus_platform_rmutex_lock (global_locks[lock]);
return TRUE;
+}
- failed:
- dbus_free (dynamic_global_locks);
-
- for (i = i - 1; i >= 0; i--)
- {
- _dbus_mutex_free (*global_locks[i]);
- *global_locks[i] = NULL;
- }
- return FALSE;
+void
+_dbus_unlock (DBusGlobalLock lock)
+{
+ _dbus_assert (lock >= 0);
+ _dbus_assert (lock < _DBUS_N_GLOBAL_LOCKS);
+
+ _dbus_platform_rmutex_unlock (global_locks[lock]);
}
+#endif /* !defined(DBUS_HAVE_STATIC_RECURSIVE_MUTEXES) */
+
/** @} */ /* end of internals */
/**
*/
/**
- *
- * Initializes threads. If this function is not called, the D-Bus
- * library will not lock any data structures. If it is called, D-Bus
- * will do locking, at some cost in efficiency. Note that this
- * function must be called BEFORE the second thread is started.
- *
- * Almost always, you should use dbus_threads_init_default() instead.
- * The raw dbus_threads_init() is only useful if you require a
- * particular thread implementation for some reason.
- *
- * A possible reason to use dbus_threads_init() rather than
- * dbus_threads_init_default() is to insert debugging checks or print
- * statements.
- *
- * dbus_threads_init() may be called more than once. The first one
- * wins and subsequent calls are ignored. (Unless you use
- * dbus_shutdown() to reset libdbus, which will let you re-init
- * threads.)
+ * Initializes threads, like dbus_threads_init_default().
+ * This version previously allowed user-specified threading
+ * primitives, but since D-Bus 1.6 it ignores them and behaves
+ * exactly like dbus_threads_init_default().
*
- * Either recursive or nonrecursive mutex functions must be specified,
- * but not both. New code should provide only the recursive functions
- * - specifying the nonrecursive ones is deprecated.
- *
- * Because this function effectively sets global state, all code
- * running in a given application must agree on the thread
- * implementation. Most code won't care which thread implementation is
- * used, so there's no problem. However, usually libraries should not
- * call dbus_threads_init() or dbus_threads_init_default(), instead
- * leaving this policy choice to applications.
- *
- * The exception is for application frameworks (GLib, Qt, etc.) and
- * D-Bus bindings based on application frameworks. These frameworks
- * define a cross-platform thread abstraction and can assume
- * applications using the framework are OK with using that thread
- * abstraction.
- *
- * However, even these app frameworks may find it easier to simply call
- * dbus_threads_init_default(), and there's no reason they shouldn't.
- *
- * @param functions functions for using threads
+ * @param functions ignored, formerly functions for using threads
* @returns #TRUE on success, #FALSE if no memory
*/
dbus_bool_t
dbus_threads_init (const DBusThreadFunctions *functions)
{
- dbus_bool_t mutex_set;
- dbus_bool_t recursive_mutex_set;
-
- _dbus_assert (functions != NULL);
-
- /* these base functions are required. Future additions to
- * DBusThreadFunctions may be optional.
- */
- _dbus_assert (functions->mask & DBUS_THREAD_FUNCTIONS_CONDVAR_NEW_MASK);
- _dbus_assert (functions->mask & DBUS_THREAD_FUNCTIONS_CONDVAR_FREE_MASK);
- _dbus_assert (functions->mask & DBUS_THREAD_FUNCTIONS_CONDVAR_WAIT_MASK);
- _dbus_assert (functions->mask & DBUS_THREAD_FUNCTIONS_CONDVAR_WAIT_TIMEOUT_MASK);
- _dbus_assert (functions->mask & DBUS_THREAD_FUNCTIONS_CONDVAR_WAKE_ONE_MASK);
- _dbus_assert (functions->mask & DBUS_THREAD_FUNCTIONS_CONDVAR_WAKE_ALL_MASK);
- _dbus_assert (functions->condvar_new != NULL);
- _dbus_assert (functions->condvar_free != NULL);
- _dbus_assert (functions->condvar_wait != NULL);
- _dbus_assert (functions->condvar_wait_timeout != NULL);
- _dbus_assert (functions->condvar_wake_one != NULL);
- _dbus_assert (functions->condvar_wake_all != NULL);
-
- /* Either the mutex function set or recursive mutex set needs
- * to be available but not both
- */
- mutex_set = (functions->mask & DBUS_THREAD_FUNCTIONS_MUTEX_NEW_MASK) &&
- (functions->mask & DBUS_THREAD_FUNCTIONS_MUTEX_FREE_MASK) &&
- (functions->mask & DBUS_THREAD_FUNCTIONS_MUTEX_LOCK_MASK) &&
- (functions->mask & DBUS_THREAD_FUNCTIONS_MUTEX_UNLOCK_MASK) &&
- functions->mutex_new &&
- functions->mutex_free &&
- functions->mutex_lock &&
- functions->mutex_unlock;
-
- recursive_mutex_set =
- (functions->mask & DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_NEW_MASK) &&
- (functions->mask & DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_FREE_MASK) &&
- (functions->mask & DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_LOCK_MASK) &&
- (functions->mask & DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_UNLOCK_MASK) &&
- functions->recursive_mutex_new &&
- functions->recursive_mutex_free &&
- functions->recursive_mutex_lock &&
- functions->recursive_mutex_unlock;
-
- if (!(mutex_set || recursive_mutex_set))
- _dbus_assert_not_reached ("Either the nonrecusrive or recursive mutex "
- "functions sets should be passed into "
- "dbus_threads_init. Neither sets were passed.");
-
- if (mutex_set && recursive_mutex_set)
- _dbus_assert_not_reached ("Either the nonrecusrive or recursive mutex "
- "functions sets should be passed into "
- "dbus_threads_init. Both sets were passed. "
- "You most likely just want to set the recursive "
- "mutex functions to avoid deadlocks in D-Bus.");
-
- /* Check that all bits in the mask actually are valid mask bits.
- * ensures people won't write code that breaks when we add
- * new bits.
- */
- _dbus_assert ((functions->mask & ~DBUS_THREAD_FUNCTIONS_ALL_MASK) == 0);
-
- if (thread_init_generation != _dbus_current_generation)
- thread_functions.mask = 0; /* allow re-init in new generation */
-
- /* Silently allow multiple init
- * First init wins and D-Bus will always use its threading system
- */
- if (thread_functions.mask != 0)
- return TRUE;
-
- thread_functions.mutex_new = functions->mutex_new;
- thread_functions.mutex_free = functions->mutex_free;
- thread_functions.mutex_lock = functions->mutex_lock;
- thread_functions.mutex_unlock = functions->mutex_unlock;
-
- thread_functions.condvar_new = functions->condvar_new;
- thread_functions.condvar_free = functions->condvar_free;
- thread_functions.condvar_wait = functions->condvar_wait;
- thread_functions.condvar_wait_timeout = functions->condvar_wait_timeout;
- thread_functions.condvar_wake_one = functions->condvar_wake_one;
- thread_functions.condvar_wake_all = functions->condvar_wake_all;
-
- if (functions->mask & DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_NEW_MASK)
- thread_functions.recursive_mutex_new = functions->recursive_mutex_new;
-
- if (functions->mask & DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_FREE_MASK)
- thread_functions.recursive_mutex_free = functions->recursive_mutex_free;
-
- if (functions->mask & DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_LOCK_MASK)
- thread_functions.recursive_mutex_lock = functions->recursive_mutex_lock;
-
- if (functions->mask & DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_UNLOCK_MASK)
- thread_functions.recursive_mutex_unlock = functions->recursive_mutex_unlock;
-
- thread_functions.mask = functions->mask;
-
- if (!init_locks ())
- return FALSE;
+ _dbus_threads_lock_platform_specific ();
+
+ if (thread_init_generation == _dbus_current_generation)
+ {
+ _dbus_threads_unlock_platform_specific ();
+ return TRUE;
+ }
+
+ if (!_dbus_threads_init_platform_specific() ||
+ !init_global_locks ())
+ {
+ _dbus_threads_unlock_platform_specific ();
+ return FALSE;
+ }
thread_init_generation = _dbus_current_generation;
-
+
+ _dbus_threads_unlock_platform_specific ();
return TRUE;
}
/* Default thread implemenation */
/**
+ * Initializes threads. If this function is not called, the D-Bus
+ * library will not lock any data structures. If it is called, D-Bus
+ * will do locking, at some cost in efficiency.
*
- * Calls dbus_threads_init() with a default set of
- * #DBusThreadFunctions appropriate for the platform.
- *
- * Most applications should use this rather than dbus_threads_init().
+ * Since D-Bus 1.7 it is safe to call this function from any thread,
+ * any number of times (but it must be called before any other
+ * libdbus API is used).
*
- * It's safe to call dbus_threads_init_default() as many times as you
- * want, but only the first time will have an effect.
+ * In D-Bus 1.6 or older, this function must be called in the main thread
+ * before any other thread starts. As a result, it is not sufficient to
+ * call this function in a library or plugin, unless the library or plugin
+ * imposes a similar requirement on its callers.
*
* dbus_shutdown() reverses the effects of this function when it
* resets all global state in libdbus.
dbus_bool_t
dbus_threads_init_default (void)
{
- return _dbus_threads_init_platform_specific ();
+ return dbus_threads_init (NULL);
}
/** @} */
#ifdef DBUS_BUILD_TESTS
-/** Fake mutex used for debugging */
-typedef struct DBusFakeMutex DBusFakeMutex;
-/** Fake mutex used for debugging */
-struct DBusFakeMutex
-{
- dbus_bool_t locked; /**< Mutex is "locked" */
-};
-
-static DBusMutex * dbus_fake_mutex_new (void);
-static void dbus_fake_mutex_free (DBusMutex *mutex);
-static dbus_bool_t dbus_fake_mutex_lock (DBusMutex *mutex);
-static dbus_bool_t dbus_fake_mutex_unlock (DBusMutex *mutex);
-static DBusCondVar* dbus_fake_condvar_new (void);
-static void dbus_fake_condvar_free (DBusCondVar *cond);
-static void dbus_fake_condvar_wait (DBusCondVar *cond,
- DBusMutex *mutex);
-static dbus_bool_t dbus_fake_condvar_wait_timeout (DBusCondVar *cond,
- DBusMutex *mutex,
- int timeout_msec);
-static void dbus_fake_condvar_wake_one (DBusCondVar *cond);
-static void dbus_fake_condvar_wake_all (DBusCondVar *cond);
-
-
-static const DBusThreadFunctions fake_functions =
-{
- DBUS_THREAD_FUNCTIONS_MUTEX_NEW_MASK |
- DBUS_THREAD_FUNCTIONS_MUTEX_FREE_MASK |
- DBUS_THREAD_FUNCTIONS_MUTEX_LOCK_MASK |
- DBUS_THREAD_FUNCTIONS_MUTEX_UNLOCK_MASK |
- DBUS_THREAD_FUNCTIONS_CONDVAR_NEW_MASK |
- DBUS_THREAD_FUNCTIONS_CONDVAR_FREE_MASK |
- DBUS_THREAD_FUNCTIONS_CONDVAR_WAIT_MASK |
- DBUS_THREAD_FUNCTIONS_CONDVAR_WAIT_TIMEOUT_MASK |
- DBUS_THREAD_FUNCTIONS_CONDVAR_WAKE_ONE_MASK|
- DBUS_THREAD_FUNCTIONS_CONDVAR_WAKE_ALL_MASK,
- dbus_fake_mutex_new,
- dbus_fake_mutex_free,
- dbus_fake_mutex_lock,
- dbus_fake_mutex_unlock,
- dbus_fake_condvar_new,
- dbus_fake_condvar_free,
- dbus_fake_condvar_wait,
- dbus_fake_condvar_wait_timeout,
- dbus_fake_condvar_wake_one,
- dbus_fake_condvar_wake_all
-};
-
-static DBusMutex *
-dbus_fake_mutex_new (void)
-{
- DBusFakeMutex *mutex;
-
- mutex = dbus_new0 (DBusFakeMutex, 1);
-
- return (DBusMutex *)mutex;
-}
-
-static void
-dbus_fake_mutex_free (DBusMutex *mutex)
-{
- DBusFakeMutex *fake = (DBusFakeMutex*) mutex;
-
- _dbus_assert (!fake->locked);
-
- dbus_free (fake);
-}
-
-static dbus_bool_t
-dbus_fake_mutex_lock (DBusMutex *mutex)
-{
- DBusFakeMutex *fake = (DBusFakeMutex*) mutex;
-
- _dbus_assert (!fake->locked);
-
- fake->locked = TRUE;
-
- return TRUE;
-}
-
-static dbus_bool_t
-dbus_fake_mutex_unlock (DBusMutex *mutex)
-{
- DBusFakeMutex *fake = (DBusFakeMutex*) mutex;
-
- _dbus_assert (fake->locked);
-
- fake->locked = FALSE;
-
- return TRUE;
-}
-
-static DBusCondVar*
-dbus_fake_condvar_new (void)
-{
- return (DBusCondVar*) _dbus_strdup ("FakeCondvar");
-}
-
-static void
-dbus_fake_condvar_free (DBusCondVar *cond)
-{
- dbus_free (cond);
-}
-
-static void
-dbus_fake_condvar_wait (DBusCondVar *cond,
- DBusMutex *mutex)
-{
-
-}
-
-static dbus_bool_t
-dbus_fake_condvar_wait_timeout (DBusCondVar *cond,
- DBusMutex *mutex,
- int timeout_msec)
-{
- return TRUE;
-}
-
-static void
-dbus_fake_condvar_wake_one (DBusCondVar *cond)
-{
-
-}
-
-static void
-dbus_fake_condvar_wake_all (DBusCondVar *cond)
-{
-
-}
dbus_bool_t
_dbus_threads_init_debug (void)
{
- return dbus_threads_init (&fake_functions);
+ return dbus_threads_init (NULL);
}
#endif /* DBUS_BUILD_TESTS */