-/* -*- mode: C; c-file-style: "gnu" -*- */
-/* dbus-threads.h D-BUS threads handling
+/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
+/* dbus-threads.h D-Bus threads handling
*
* Copyright (C) 2002 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
*
*/
#if !defined (DBUS_INSIDE_DBUS_H) && !defined (DBUS_COMPILATION)
DBUS_BEGIN_DECLS
+/**
+ * @addtogroup DBusThreads
+ * @{
+ */
+
+/** An opaque mutex type provided by the #DBusThreadFunctions implementation installed by dbus_threads_init(). */
typedef struct DBusMutex DBusMutex;
+/** An opaque condition variable type provided by the #DBusThreadFunctions implementation installed by dbus_threads_init(). */
typedef struct DBusCondVar DBusCondVar;
+/** Deprecated, provide DBusRecursiveMutexNewFunction instead. */
typedef DBusMutex* (* DBusMutexNewFunction) (void);
+/** Deprecated, provide DBusRecursiveMutexFreeFunction instead. */
typedef void (* DBusMutexFreeFunction) (DBusMutex *mutex);
+/** Deprecated, provide DBusRecursiveMutexLockFunction instead. Return value is lock success, but gets ignored in practice. */
typedef dbus_bool_t (* DBusMutexLockFunction) (DBusMutex *mutex);
+/** Deprecated, provide DBusRecursiveMutexUnlockFunction instead. Return value is unlock success, but gets ignored in practice. */
typedef dbus_bool_t (* DBusMutexUnlockFunction) (DBusMutex *mutex);
+/** Creates a new recursively-lockable mutex, or returns #NULL if not
+ * enough memory. Can only fail due to lack of memory. Found in
+ * #DBusThreadFunctions. Do not just use PTHREAD_MUTEX_RECURSIVE for
+ * this, because it does not save/restore the recursion count when
+ * waiting on a condition. libdbus requires the Java-style behavior
+ * where the mutex is fully unlocked to wait on a condition.
+ */
+typedef DBusMutex* (* DBusRecursiveMutexNewFunction) (void);
+/** Frees a recursively-lockable mutex. Found in #DBusThreadFunctions.
+ */
+typedef void (* DBusRecursiveMutexFreeFunction) (DBusMutex *mutex);
+/** Locks a recursively-lockable mutex. Found in #DBusThreadFunctions.
+ * Can only fail due to lack of memory.
+ */
+typedef void (* DBusRecursiveMutexLockFunction) (DBusMutex *mutex);
+/** Unlocks a recursively-lockable mutex. Found in #DBusThreadFunctions.
+ * Can only fail due to lack of memory.
+ */
+typedef void (* DBusRecursiveMutexUnlockFunction) (DBusMutex *mutex);
+
+/** Creates a new condition variable. Found in #DBusThreadFunctions.
+ * Can only fail (returning #NULL) due to lack of memory.
+ */
typedef DBusCondVar* (* DBusCondVarNewFunction) (void);
+/** Frees a condition variable. Found in #DBusThreadFunctions.
+ */
typedef void (* DBusCondVarFreeFunction) (DBusCondVar *cond);
+
+/** Waits on a condition variable. Found in
+ * #DBusThreadFunctions. Must work with either a recursive or
+ * nonrecursive mutex, whichever the thread implementation
+ * provides. Note that PTHREAD_MUTEX_RECURSIVE does not work with
+ * condition variables (does not save/restore the recursion count) so
+ * don't try using simply pthread_cond_wait() and a
+ * PTHREAD_MUTEX_RECURSIVE to implement this, it won't work right.
+ *
+ * Has no error conditions. Must succeed if it returns.
+ */
typedef void (* DBusCondVarWaitFunction) (DBusCondVar *cond,
DBusMutex *mutex);
+
+/** Waits on a condition variable with a timeout. Found in
+ * #DBusThreadFunctions. Returns #TRUE if the wait did not
+ * time out, and #FALSE if it did.
+ *
+ * Has no error conditions. Must succeed if it returns.
+ */
typedef dbus_bool_t (* DBusCondVarWaitTimeoutFunction) (DBusCondVar *cond,
DBusMutex *mutex,
int timeout_milliseconds);
+/** Wakes one waiting thread on a condition variable. Found in #DBusThreadFunctions.
+ *
+ * Has no error conditions. Must succeed if it returns.
+ */
typedef void (* DBusCondVarWakeOneFunction) (DBusCondVar *cond);
+
+/** Wakes all waiting threads on a condition variable. Found in #DBusThreadFunctions.
+ *
+ * Has no error conditions. Must succeed if it returns.
+ */
typedef void (* DBusCondVarWakeAllFunction) (DBusCondVar *cond);
+/**
+ * Flags indicating which functions are present in #DBusThreadFunctions. Used to allow
+ * the library to detect older callers of dbus_threads_init() if new possible functions
+ * are added to #DBusThreadFunctions.
+ */
typedef enum
{
DBUS_THREAD_FUNCTIONS_MUTEX_NEW_MASK = 1 << 0,
DBUS_THREAD_FUNCTIONS_CONDVAR_WAIT_TIMEOUT_MASK = 1 << 7,
DBUS_THREAD_FUNCTIONS_CONDVAR_WAKE_ONE_MASK = 1 << 8,
DBUS_THREAD_FUNCTIONS_CONDVAR_WAKE_ALL_MASK = 1 << 9,
-
- DBUS_THREAD_FUNCTIONS_ALL_MASK = (1 << 10) - 1
+ DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_NEW_MASK = 1 << 10,
+ DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_FREE_MASK = 1 << 11,
+ DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_LOCK_MASK = 1 << 12,
+ DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_UNLOCK_MASK = 1 << 13,
+ DBUS_THREAD_FUNCTIONS_ALL_MASK = (1 << 14) - 1
} DBusThreadFunctionsMask;
/**
- * Functions that must be implemented to make the D-BUS
- * library thread-aware.
+ * Functions that must be implemented to make the D-Bus library
+ * thread-aware.
+ *
+ * If you supply both recursive and non-recursive mutexes,
+ * libdbus will use the non-recursive version for condition variables,
+ * and the recursive version in other contexts.
+ *
+ * The condition variable functions have to work with nonrecursive
+ * mutexes if you provide those, or with recursive mutexes if you
+ * don't.
*/
typedef struct
{
unsigned int mask; /**< Mask indicating which functions are present. */
- DBusMutexNewFunction mutex_new; /**< Function to create a mutex */
- DBusMutexFreeFunction mutex_free; /**< Function to free a mutex */
- DBusMutexLockFunction mutex_lock; /**< Function to lock a mutex */
- DBusMutexUnlockFunction mutex_unlock; /**< Function to unlock a mutex */
+ DBusMutexNewFunction mutex_new; /**< Function to create a mutex; optional and deprecated. */
+ DBusMutexFreeFunction mutex_free; /**< Function to free a mutex; optional and deprecated. */
+ DBusMutexLockFunction mutex_lock; /**< Function to lock a mutex; optional and deprecated. */
+ DBusMutexUnlockFunction mutex_unlock; /**< Function to unlock a mutex; optional and deprecated. */
DBusCondVarNewFunction condvar_new; /**< Function to create a condition variable */
DBusCondVarFreeFunction condvar_free; /**< Function to free a condition variable */
DBusCondVarWaitTimeoutFunction condvar_wait_timeout; /**< Function to wait on a condition with a timeout */
DBusCondVarWakeOneFunction condvar_wake_one; /**< Function to wake one thread waiting on the condition */
DBusCondVarWakeAllFunction condvar_wake_all; /**< Function to wake all threads waiting on the condition */
-
+
+ DBusRecursiveMutexNewFunction recursive_mutex_new; /**< Function to create a recursive mutex */
+ DBusRecursiveMutexFreeFunction recursive_mutex_free; /**< Function to free a recursive mutex */
+ DBusRecursiveMutexLockFunction recursive_mutex_lock; /**< Function to lock a recursive mutex */
+ DBusRecursiveMutexUnlockFunction recursive_mutex_unlock; /**< Function to unlock a recursive mutex */
+
void (* padding1) (void); /**< Reserved for future expansion */
void (* padding2) (void); /**< Reserved for future expansion */
void (* padding3) (void); /**< Reserved for future expansion */
void (* padding4) (void); /**< Reserved for future expansion */
- void (* padding5) (void); /**< Reserved for future expansion */
- void (* padding6) (void); /**< Reserved for future expansion */
- void (* padding7) (void); /**< Reserved for future expansion */
- void (* padding8) (void); /**< Reserved for future expansion */
} DBusThreadFunctions;
+DBUS_EXPORT
dbus_bool_t dbus_threads_init (const DBusThreadFunctions *functions);
+DBUS_EXPORT
+dbus_bool_t dbus_threads_init_default (void);
+
+/** @} */
DBUS_END_DECLS