semaphore.h@ 31155

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1	/** @file
2	* IPRT - Semaphore.
3	*/
4
5	/*
6	* Copyright (C) 2006-2010 Oracle Corporation
7	*
8	* This file is part of VirtualBox Open Source Edition (OSE), as
9	* available from http://www.virtualbox.org. This file is free software;
10	* you can redistribute it and/or modify it under the terms of the GNU
11	* General Public License (GPL) as published by the Free Software
12	* Foundation, in version 2 as it comes in the "COPYING" file of the
13	* VirtualBox OSE distribution. VirtualBox OSE is distributed in the
14	* hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
15	*
16	* The contents of this file may alternatively be used under the terms
17	* of the Common Development and Distribution License Version 1.0
18	* (CDDL) only, as it comes in the "COPYING.CDDL" file of the
19	* VirtualBox OSE distribution, in which case the provisions of the
20	* CDDL are applicable instead of those of the GPL.
21	*
22	* You may elect to license modified versions of this file under the
23	* terms and conditions of either the GPL or the CDDL or both.
24	*/
25
26	#ifndef ___iprt_semaphore_h
27	#define ___iprt_semaphore_h
28
29	#include <iprt/cdefs.h>
30	#include <iprt/types.h>
31	#if defined(RT_LOCK_STRICT_ORDER) && defined(IN_RING3)
32	# include <iprt/lockvalidator.h>
33	#endif
34
35
36	RT_C_DECLS_BEGIN
37
38	/** @defgroup grp_rt_sems RTSem - Semaphores
39	*
40	* This module implements all kinds of event and mutex semaphores; in addition
41	* to these, IPRT implements "critical sections", which are fast recursive
42	* mutexes (see @ref grp_rt_critsect ). C++ users may find @ref grp_rt_lock
43	* interesting.
44	*
45	* @ingroup grp_rt
46	* @{
47	*/
48
49
50	/** @defgroup grp_rt_sems_event RTSemEvent - Single Release Event Semaphores
51	*
52	* Event semaphores can be used for inter-thread communication when one thread
53	* wants to notify another thread that something happened. A thread can block
54	* ("wait") on an event semaphore until it is signalled by another thread; see
55	* RTSemEventCreate, RTSemEventSignal and RTSemEventWait.
56	*
57	* @{ */
58
59	/**
60	* Create an event semaphore.
61	*
62	* @returns iprt status code.
63	* @param phEventSem Where to store the handle to the newly created
64	* event semaphore.
65	*/
66	RTDECL(int) RTSemEventCreate(PRTSEMEVENT phEventSem);
67
68	/**
69	* Create an event semaphore.
70	*
71	* @returns iprt status code.
72	* @param phEventSem Where to store the handle to the newly created
73	* event semaphore.
74	* @param fFlags Flags, any combination of the
75	* RTSEMEVENT_FLAGS_XXX \#defines.
76	* @param hClass The class (no reference consumed). Since we
77	* don't do order checks on event semaphores, the
78	* use of the class is limited to controlling the
79	* timeout threshold for deadlock detection.
80	* @param pszNameFmt Name format string for the lock validator,
81	* optional (NULL). Max length is 32 bytes.
82	* @param ... Format string arguments.
83	*/
84	RTDECL(int) RTSemEventCreateEx(PRTSEMEVENT phEventSem, uint32_t fFlags, RTLOCKVALCLASS hClass, const char *pszNameFmt, ...);
85
86	/** @name RTSemMutexCreateEx flags
87	* @{ */
88	/** Disables lock validation. */
89	#define RTSEMEVENT_FLAGS_NO_LOCK_VAL UINT32_C(0x00000001)
90	/** @} */
91
92	/**
93	* Destroy an event semaphore.
94	*
95	* @returns iprt status code.
96	* @param hEventSem Handle of the event sempahore. NIL_RTSEMEVENT
97	* is quitely ignored (VINF_SUCCESS).
98	*/
99	RTDECL(int) RTSemEventDestroy(RTSEMEVENT hEventSem);
100
101	/**
102	* Signal an event semaphore.
103	*
104	* The event semaphore will be signaled and automatically reset after exactly
105	* one thread have successfully returned from RTSemEventWait() after
106	* waiting/polling on that semaphore.
107	*
108	* @returns iprt status code.
109	* @param hEventSem The event semaphore to signal.
110	*
111	* @remarks ring-0: This works when preemption is disabled. However it is
112	* system specific whether it works in interrupt context or with
113	* interrupts disabled.
114	*/
115	RTDECL(int) RTSemEventSignal(RTSEMEVENT hEventSem);
116
117	/**
118	* Wait for the event semaphore to be signaled, resume on interruption.
119	*
120	* This function will resume if the wait is interrupted by an async system event
121	* (like a unix signal) or similar.
122	*
123	* @returns iprt status code.
124	* Will not return VERR_INTERRUPTED.
125	* @param hEventSem The event semaphore to wait on.
126	* @param cMillies Number of milliseconds to wait.
127	*/
128	RTDECL(int) RTSemEventWait(RTSEMEVENT hEventSem, RTMSINTERVAL cMillies);
129
130	/**
131	* Wait for the event semaphore to be signaled, return on interruption.
132	*
133	* This function will not resume the wait if interrupted.
134	*
135	* @returns iprt status code.
136	* @param hEventSem The event semaphore to wait on.
137	* @param cMillies Number of milliseconds to wait.
138	*/
139	RTDECL(int) RTSemEventWaitNoResume(RTSEMEVENT hEventSem, RTMSINTERVAL cMillies);
140
141	/**
142	* Sets the signaller thread to one specific thread.
143	*
144	* This is only used for validating usage and deadlock detection. When used
145	* after calls to RTSemEventAddSignaller, the specified thread will be the only
146	* signalling thread.
147	*
148	* @param hEventSem The event semaphore.
149	* @param hThread The thread that will signal it. Pass
150	* NIL_RTTHREAD to indicate that there is no
151	* special signalling thread.
152	*/
153	RTDECL(void) RTSemEventSetSignaller(RTSEMEVENT hEventSem, RTTHREAD hThread);
154
155	/**
156	* To add more signalling threads.
157	*
158	* First call RTSemEventSetSignaller then add further threads with this.
159	*
160	* @param hEventSem The event semaphore.
161	* @param hThread The thread that will signal it. NIL_RTTHREAD is
162	* not accepted.
163	*/
164	RTDECL(void) RTSemEventAddSignaller(RTSEMEVENT hEventSem, RTTHREAD hThread);
165
166	/**
167	* To remove a signalling thread.
168	*
169	* Reverts work done by RTSemEventAddSignaller and RTSemEventSetSignaller.
170	*
171	* @param hEventSem The event semaphore.
172	* @param hThread A previously added thread.
173	*/
174	RTDECL(void) RTSemEventRemoveSignaller(RTSEMEVENT hEventSem, RTTHREAD hThread);
175
176	/** @} */
177
178
179	/** @defgroup grp_rt_sems_event_multi RTSemEventMulti - Multiple Release Event Semaphores
180	*
181	* A variant of @ref grp_rt_sems_event where all threads will be unblocked when
182	* signalling the semaphore.
183	*
184	* @{ */
185
186	/**
187	* Creates a multiple release event semaphore.
188	*
189	* @returns iprt status code.
190	* @param phEventMultiSem Where to store the handle to the newly created
191	* multiple release event semaphore.
192	*/
193	RTDECL(int) RTSemEventMultiCreate(PRTSEMEVENTMULTI phEventMultiSem);
194
195	/**
196	* Creates a multiple release event semaphore.
197	*
198	* @returns iprt status code.
199	* @param phEventMultiSem Where to store the handle to the newly created
200	* multiple release event semaphore.
201	* @param fFlags Flags, any combination of the
202	* RTSEMEVENTMULTI_FLAGS_XXX \#defines.
203	* @param hClass The class (no reference consumed). Since we
204	* don't do order checks on event semaphores, the
205	* use of the class is limited to controlling the
206	* timeout threshold for deadlock detection.
207	* @param pszNameFmt Name format string for the lock validator,
208	* optional (NULL). Max length is 32 bytes.
209	* @param ... Format string arguments.
210	*/
211	RTDECL(int) RTSemEventMultiCreateEx(PRTSEMEVENTMULTI phEventMultiSem, uint32_t fFlags, RTLOCKVALCLASS hClass,
212	const char *pszNameFmt, ...);
213
214	/** @name RTSemMutexCreateEx flags
215	* @{ */
216	/** Disables lock validation. */
217	#define RTSEMEVENTMULTI_FLAGS_NO_LOCK_VAL UINT32_C(0x00000001)
218	/** @} */
219
220	/**
221	* Destroy an event multi semaphore.
222	*
223	* @returns iprt status code.
224	* @param hEventMultiSem The multiple release event sempahore. NIL is
225	* quietly ignored (VINF_SUCCESS).
226	*/
227	RTDECL(int) RTSemEventMultiDestroy(RTSEMEVENTMULTI hEventMultiSem);
228
229	/**
230	* Signal an event multi semaphore.
231	*
232	* @returns iprt status code.
233	* @param hEventMultiSem The multiple release event sempahore.
234	*
235	* @remarks ring-0: This works when preemption is disabled. However it is
236	* system specific whether it works in interrupt context or with
237	* interrupts disabled.
238	*/
239	RTDECL(int) RTSemEventMultiSignal(RTSEMEVENTMULTI hEventMultiSem);
240
241	/**
242	* Resets an event multi semaphore to non-signaled state.
243	*
244	* @returns iprt status code.
245	* @param hEventMultiSem The multiple release event sempahore.
246	*/
247	RTDECL(int) RTSemEventMultiReset(RTSEMEVENTMULTI hEventMultiSem);
248
249	/**
250	* Wait for the event multi semaphore to be signaled, resume on interruption.
251	*
252	* This function will resume if the wait is interrupted by an async
253	* system event (like a unix signal) or similar.
254	*
255	* @returns iprt status code.
256	* Will not return VERR_INTERRUPTED.
257	* @param hEventMultiSem The multiple release event sempahore.
258	* @param cMillies Number of milliseconds to wait.
259	*/
260	RTDECL(int) RTSemEventMultiWait(RTSEMEVENTMULTI hEventMultiSem, RTMSINTERVAL cMillies);
261
262
263	/**
264	* Wait for the event multi semaphore to be signaled, return on interruption.
265	*
266	* This function will not resume the wait if interrupted.
267	*
268	* @returns iprt status code.
269	* @param hEventMultiSem The multiple release event sempahore.
270	* @param cMillies Number of milliseconds to wait.
271	*/
272	RTDECL(int) RTSemEventMultiWaitNoResume(RTSEMEVENTMULTI hEventMultiSem, RTMSINTERVAL cMillies);
273
274	/**
275	* Sets the signaller thread to one specific thread.
276	*
277	* This is only used for validating usage and deadlock detection. When used
278	* after calls to RTSemEventAddSignaller, the specified thread will be the only
279	* signalling thread.
280	*
281	* @param hEventMultiSem The multiple release event semaphore.
282	* @param hThread The thread that will signal it. Pass
283	* NIL_RTTHREAD to indicate that there is no
284	* special signalling thread.
285	*/
286	RTDECL(void) RTSemEventMultiSetSignaller(RTSEMEVENTMULTI hEventMultiSem, RTTHREAD hThread);
287
288	/**
289	* To add more signalling threads.
290	*
291	* First call RTSemEventSetSignaller then add further threads with this.
292	*
293	* @param hEventMultiSem The multiple release event semaphore.
294	* @param hThread The thread that will signal it. NIL_RTTHREAD is
295	* not accepted.
296	*/
297	RTDECL(void) RTSemEventMultiAddSignaller(RTSEMEVENTMULTI hEventMultiSem, RTTHREAD hThread);
298
299	/**
300	* To remove a signalling thread.
301	*
302	* Reverts work done by RTSemEventAddSignaller and RTSemEventSetSignaller.
303	*
304	* @param hEventMultiSem The multiple release event semaphore.
305	* @param hThread A previously added thread.
306	*/
307	RTDECL(void) RTSemEventMultiRemoveSignaller(RTSEMEVENTMULTI hEventMultiSem, RTTHREAD hThread);
308
309	/** @} */
310
311
312	/** @defgroup grp_rt_sems_mutex RTSemMutex - Mutex semaphores.
313	*
314	* Mutex semaphores protect a section of code or data to which access must be
315	* exclusive. Only one thread can hold access to a critical section at one
316	* time. See RTSemMutexCreate, RTSemMutexRequest and RTSemMutexRelease.
317	*
318	* @remarks These are less efficient than "fast mutexes" and "critical
319	* sections", which IPRT implements as well; see @ref
320	* grp_rt_sems_fast_mutex and @ref grp_rt_critsect .
321	*
322	* @{ */
323
324	/**
325	* Create a mutex semaphore.
326	*
327	* @returns iprt status code.
328	* @param phMutexSem Where to store the mutex semaphore handle.
329	*/
330	RTDECL(int) RTSemMutexCreate(PRTSEMMUTEX phMutexSem);
331
332	/**
333	* Creates a read/write semaphore.
334	*
335	* @returns iprt status code.
336	* @param phRWSem Where to store the handle to the newly created
337	* RW semaphore.
338	* @param fFlags Flags, any combination of the
339	* RTSEMMUTEX_FLAGS_XXX \#defines.
340	* @param hClass The class (no reference consumed). If NIL, no
341	* lock order validation will be performed on this
342	* lock.
343	* @param uSubClass The sub-class. This is used to define lock
344	* order within a class. RTLOCKVAL_SUB_CLASS_NONE
345	* is the recommended value here.
346	* @param pszNameFmt Name format string for the lock validator,
347	* optional (NULL). Max length is 32 bytes.
348	* @param ... Format string arguments.
349	*/
350	RTDECL(int) RTSemMutexCreateEx(PRTSEMMUTEX phMutexSem, uint32_t fFlags,
351	RTLOCKVALCLASS hClass, uint32_t uSubClass, const char *pszNameFmt, ...);
352
353	/** @name RTSemMutexCreateEx flags
354	* @{ */
355	/** Disables lock validation. */
356	#define RTSEMMUTEX_FLAGS_NO_LOCK_VAL UINT32_C(0x00000001)
357	/** @} */
358
359
360	/**
361	* Destroy a mutex semaphore.
362	*
363	* @returns iprt status code.
364	* @param hMutexSem The mutex semaphore to destroy. NIL is quitely
365	* ignored (VINF_SUCCESS).
366	*/
367	RTDECL(int) RTSemMutexDestroy(RTSEMMUTEX hMutexSem);
368
369	/**
370	* Changes the lock validator sub-class of the mutex semaphore.
371	*
372	* It is recommended to try make sure that nobody is using this sempahore while
373	* changing the value.
374	*
375	* @returns The old sub-class. RTLOCKVAL_SUB_CLASS_INVALID is returns if the
376	* lock validator isn't compiled in or either of the parameters are
377	* invalid.
378	* @param hMutexSem The handle to the mutex semaphore.
379	* @param uSubClass The new sub-class value.
380	*/
381	RTDECL(uint32_t) RTSemMutexSetSubClass(RTSEMMUTEX hMutexSem, uint32_t uSubClass);
382
383	/**
384	* Request ownership of a mutex semaphore, resume on interruption.
385	*
386	* This function will resume if the wait is interrupted by an async
387	* system event (like a unix signal) or similar.
388	*
389	* The same thread may request a mutex semaphore multiple times,
390	* a nested counter is kept to make sure it's released on the right
391	* RTSemMutexRelease() call.
392	*
393	* @returns iprt status code.
394	* Will not return VERR_INTERRUPTED.
395	* @param hMutexSem The mutex semaphore to request ownership over.
396	* @param cMillies The number of milliseconds to wait.
397	*/
398	RTDECL(int) RTSemMutexRequest(RTSEMMUTEX hMutexSem, RTMSINTERVAL cMillies);
399
400	/**
401	* Request ownership of a mutex semaphore, return on interruption.
402	*
403	* This function will not resume the wait if interrupted.
404	*
405	* The same thread may request a mutex semaphore multiple times,
406	* a nested counter is kept to make sure it's released on the right
407	* RTSemMutexRelease() call.
408	*
409	* @returns iprt status code.
410	* @param hMutexSem The mutex semaphore to request ownership over.
411	* @param cMillies The number of milliseconds to wait.
412	*/
413	RTDECL(int) RTSemMutexRequestNoResume(RTSEMMUTEX hMutexSem, RTMSINTERVAL cMillies);
414
415	/**
416	* Debug version of RTSemMutexRequest that tracks the location.
417	*
418	* @returns iprt status code.
419	* Will not return VERR_INTERRUPTED.
420	* @param hMutexSem The mutex semaphore to request ownership over.
421	* @param cMillies The number of milliseconds to wait.
422	* @param uId Some kind of locking location ID. Typically a
423	* return address up the stack. Optional (0).
424	* @param pszFile The file where the lock is being acquired from.
425	* Optional.
426	* @param iLine The line number in that file. Optional (0).
427	* @param pszFunction The functionn where the lock is being acquired
428	* from. Optional.
429	*/
430	RTDECL(int) RTSemMutexRequestDebug(RTSEMMUTEX hMutexSem, RTMSINTERVAL cMillies, RTHCUINTPTR uId, RT_SRC_POS_DECL);
431
432	/**
433	* Debug version of RTSemMutexRequestNoResume that tracks the location.
434	*
435	* @returns iprt status code.
436	* @param hMutexSem The mutex semaphore to request ownership over.
437	* @param cMillies The number of milliseconds to wait.
438	* @param uId Some kind of locking location ID. Typically a
439	* return address up the stack. Optional (0).
440	* @param pszFile The file where the lock is being acquired from.
441	* Optional.
442	* @param iLine The line number in that file. Optional (0).
443	* @param pszFunction The functionn where the lock is being acquired
444	* from. Optional.
445	*/
446	RTDECL(int) RTSemMutexRequestNoResumeDebug(RTSEMMUTEX hMutexSem, RTMSINTERVAL cMillies, RTHCUINTPTR uId, RT_SRC_POS_DECL);
447
448	/**
449	* Release the ownership of a mutex semaphore.
450	*
451	* @returns iprt status code.
452	* @param hMutexSem The mutex to release the ownership of. It goes
453	* without saying the the calling thread must own
454	* it.
455	*/
456	RTDECL(int) RTSemMutexRelease(RTSEMMUTEX hMutexSem);
457
458	/**
459	* Checks if the mutex semaphore is owned or not.
460	*
461	* @returns true if owned, false if not.
462	* @param hMutexSem The mutex semaphore.
463	*/
464	RTDECL(bool) RTSemMutexIsOwned(RTSEMMUTEX hMutexSem);
465
466	/* Strict build: Remap the two request calls to the debug versions. */
467	#ifdef RT_STRICT
468	# ifdef ___iprt_asm_h
469	# define RTSemMutexRequest(pCritSect, cMillies) RTSemMutexRequestDebug((pCritSect), (cMillies), (uintptr_t)ASMReturnAddress(), RT_SRC_POS)
470	# define RTSemMutexRequestNoResume(pCritSect, cMillies) RTSemMutexRequestNoResumeDebug((pCritSect), (cMillies), (uintptr_t)ASMReturnAddress(), RT_SRC_POS)
471	# else
472	# define RTSemMutexRequest(pCritSect, cMillies) RTSemMutexRequestDebug((pCritSect), (cMillies), 0, RT_SRC_POS)
473	# define RTSemMutexRequestNoResume(pCritSect, cMillies) RTSemMutexRequestNoResumeDebug((pCritSect), (cMillies), 0, RT_SRC_POS)
474	# endif
475	#endif
476
477	/* Strict lock order: Automatically classify locks by init location. */
478	#if defined(RT_LOCK_STRICT_ORDER) && defined(IN_RING3)
479	# define RTSemMutexCreate(phMutexSem) \
480	RTSemMutexCreateEx((phMutexSem), 0 /fFlags/, \
481	RTLockValidatorClassForSrcPos(RT_SRC_POS, NULL), \
482	RTLOCKVAL_SUB_CLASS_NONE, NULL)
483	#endif
484
485	/** @} */
486
487
488	/** @defgroup grp_rt_sems_fast_mutex RTSemFastMutex - Fast Mutex Semaphores
489	*
490	* Fast mutexes work like regular mutexes in that they allow only a single
491	* thread access to a critical piece of code or data. As opposed to mutexes,
492	* they require no syscall if the fast mutex is not held (like critical
493	* sections). Unlike critical sections however, they are not recursive.
494	*
495	* @{ */
496
497	/**
498	* Create a fast mutex semaphore.
499	*
500	* @returns iprt status code.
501	* @param phFastMtx Where to store the handle to the newly created
502	* fast mutex semaphore.
503	*
504	* @remarks Fast mutex semaphores are not recursive.
505	*/
506	RTDECL(int) RTSemFastMutexCreate(PRTSEMFASTMUTEX phFastMtx);
507
508	/**
509	* Destroy a fast mutex semaphore.
510	*
511	* @returns iprt status code.
512	* @param hFastMtx Handle to the fast mutex semaphore. NIL is
513	* quietly ignored (VINF_SUCCESS).
514	*/
515	RTDECL(int) RTSemFastMutexDestroy(RTSEMFASTMUTEX hFastMtx);
516
517	/**
518	* Request ownership of a fast mutex semaphore.
519	*
520	* The same thread may request a mutex semaphore multiple times,
521	* a nested counter is kept to make sure it's released on the right
522	* RTSemMutexRelease() call.
523	*
524	* @returns iprt status code.
525	* @param hFastMtx Handle to the fast mutex semaphore.
526	*/
527	RTDECL(int) RTSemFastMutexRequest(RTSEMFASTMUTEX hFastMtx);
528
529	/**
530	* Release the ownership of a fast mutex semaphore.
531	*
532	* @returns iprt status code.
533	* @param hFastMtx Handle to the fast mutex semaphore. It goes
534	* without saying the the calling thread must own
535	* it.
536	*/
537	RTDECL(int) RTSemFastMutexRelease(RTSEMFASTMUTEX hFastMtx);
538
539	/** @} */
540
541
542	/** @defgroup grp_rt_sems_spin_mutex RTSemSpinMutex - Spinning Mutex Semaphores
543	*
544	* A very adaptive variant of mutex semaphore that is tailored for the ring-0
545	* logger.
546	*
547	* @{ */
548
549	/**
550	* Creates a spinning mutex semaphore.
551	*
552	* @returns iprt status code.
553	* @retval VERR_INVALID_PARAMETER on invalid flags.
554	* @retval VERR_NO_MEMORY if out of memory for the semaphore structure and
555	* handle.
556	*
557	* @param phSpinMtx Where to return the handle to the create semaphore.
558	* @param fFlags Flags, see RTSEMSPINMUTEX_FLAGS_XXX.
559	*/
560	RTDECL(int) RTSemSpinMutexCreate(PRTSEMSPINMUTEX phSpinMtx, uint32_t fFlags);
561
562	/** @name RTSemSpinMutexCreate flags.
563	* @{ */
564	/** Always take the semaphore in a IRQ safe way.
565	* (In plain words: always disable interrupts.) */
566	#define RTSEMSPINMUTEX_FLAGS_IRQ_SAFE RT_BIT_32(0)
567	/** Mask of valid flags. */
568	#define RTSEMSPINMUTEX_FLAGS_VALID_MASK UINT32_C(0x00000001)
569	/** @} */
570
571	/**
572	* Destroys a spinning mutex semaphore.
573	*
574	* @returns iprt status code.
575	* @retval VERR_INVALID_HANDLE (or crash) if the handle is invalid. (NIL will
576	* not cause this status.)
577	*
578	* @param hSpinMtx The semaphore handle. NIL_RTSEMSPINMUTEX is ignored
579	* quietly (VINF_SUCCESS).
580	*/
581	RTDECL(int) RTSemSpinMutexDestroy(RTSEMSPINMUTEX hSpinMtx);
582
583	/**
584	* Request the spinning mutex semaphore.
585	*
586	* This may block if the context we're called in allows this. If not it will
587	* spin. If called in an interrupt context, we will only spin if the current
588	* owner isn't interrupted. Also, on some systems it is not always possible to
589	* wake up blocking threads in all contexts, so, which will either be indicated
590	* by returning VERR_SEM_BAD_CONTEXT or by temporarily switching the semaphore
591	* into pure spinlock state.
592	*
593	* Preemption will be disabled upon return. IRQs may also be disabled.
594	*
595	* @returns iprt status code.
596	* @retval VERR_SEM_BAD_CONTEXT if the context it's called in isn't suitable
597	* for releasing it if someone is sleeping on it.
598	* @retval VERR_SEM_DESTROYED if destroyed.
599	* @retval VERR_SEM_NESTED if held by the caller. Asserted.
600	* @retval VERR_INVALID_HANDLE if the handle is invalid. Asserted
601	*
602	* @param hSpinMtx The semaphore handle.
603	*/
604	RTDECL(int) RTSemSpinMutexRequest(RTSEMSPINMUTEX hSpinMtx);
605
606	/**
607	* Like RTSemSpinMutexRequest but it won't block or spin if the semaphore is
608	* held by someone else.
609	*
610	* @returns iprt status code.
611	* @retval VERR_SEM_BUSY if held by someone else.
612	* @retval VERR_SEM_DESTROYED if destroyed.
613	* @retval VERR_SEM_NESTED if held by the caller. Asserted.
614	* @retval VERR_INVALID_HANDLE if the handle is invalid. Asserted
615	*
616	* @param hSpinMtx The semaphore handle.
617	*/
618	RTDECL(int) RTSemSpinMutexTryRequest(RTSEMSPINMUTEX hSpinMtx);
619
620	/**
621	* Releases the semaphore previously acquired by RTSemSpinMutexRequest or
622	* RTSemSpinMutexTryRequest.
623	*
624	* @returns iprt status code.
625	* @retval VERR_SEM_DESTROYED if destroyed.
626	* @retval VERR_NOT_OWNER if not owner. Asserted.
627	* @retval VERR_INVALID_HANDLE if the handle is invalid. Asserted.
628	*
629	* @param hSpinMtx The semaphore handle.
630	*/
631	RTDECL(int) RTSemSpinMutexRelease(RTSEMSPINMUTEX hSpinMtx);
632
633	/** @} */
634
635
636	/** @defgroup grp_rt_sem_rw RTSemRW - Read / Write Semaphores
637	*
638	* Read/write semaphores are a fancier version of mutexes in that they grant
639	* read access to the protected data to several threads at the same time but
640	* allow only one writer at a time. This can make code scale better at the
641	* expense of slightly more overhead in mutex management.
642	*
643	* @{ */
644
645	/**
646	* Creates a read/write semaphore.
647	*
648	* @returns iprt status code.
649	* @param phRWSem Where to store the handle to the newly created
650	* RW semaphore.
651	*/
652	RTDECL(int) RTSemRWCreate(PRTSEMRW phRWSem);
653
654	/**
655	* Creates a read/write semaphore.
656	*
657	* @returns iprt status code.
658	* @param phRWSem Where to store the handle to the newly created
659	* RW semaphore.
660	* @param fFlags Flags, any combination of the RTSEMRW_FLAGS_XXX
661	* \#defines.
662	* @param hClass The class (no reference consumed). If NIL, no
663	* lock order validation will be performed on this
664	* lock.
665	* @param uSubClass The sub-class. This is used to define lock
666	* order within a class. RTLOCKVAL_SUB_CLASS_NONE
667	* is the recommended value here.
668	* @param pszNameFmt Name format string for the lock validator,
669	* optional (NULL). Max length is 32 bytes.
670	* @param ... Format string arguments.
671	*/
672	RTDECL(int) RTSemRWCreateEx(PRTSEMRW phRWSem, uint32_t fFlags,
673	RTLOCKVALCLASS hClass, uint32_t uSubClass, const char *pszNameFmt, ...);
674
675	/** @name RTSemRWCreateEx flags
676	* @{ */
677	/** Disables lock validation. */
678	#define RTSEMRW_FLAGS_NO_LOCK_VAL UINT32_C(0x00000001)
679	/** @} */
680
681	/**
682	* Destroys a read/write semaphore.
683	*
684	* @returns iprt status code.
685	* @param hRWSem Handle to the read/write semaphore. NIL is
686	* quitly ignored (VINF_SUCCESS).
687	*/
688	RTDECL(int) RTSemRWDestroy(RTSEMRW hRWSem);
689
690	/**
691	* Changes the lock validator sub-class of the read/write semaphore.
692	*
693	* It is recommended to try make sure that nobody is using this sempahore while
694	* changing the value.
695	*
696	* @returns The old sub-class. RTLOCKVAL_SUB_CLASS_INVALID is returns if the
697	* lock validator isn't compiled in or either of the parameters are
698	* invalid.
699	* @param hRWSem Handle to the read/write semaphore.
700	* @param uSubClass The new sub-class value.
701	*/
702	RTDECL(uint32_t) RTSemRWSetSubClass(RTSEMRW hRWSem, uint32_t uSubClass);
703
704	/**
705	* Request read access to a read/write semaphore, resume on interruption
706	*
707	* @returns iprt status code.
708	* @retval VINF_SUCCESS on success.
709	* @retval VERR_INTERRUPT if the wait was interrupted.
710	* @retval VERR_INVALID_HANDLE if hRWSem is invalid.
711	*
712	* @param hRWSem Handle to the read/write semaphore.
713	* @param cMillies The number of milliseconds to wait.
714	*/
715	RTDECL(int) RTSemRWRequestRead(RTSEMRW hRWSem, RTMSINTERVAL cMillies);
716
717	/**
718	* Request read access to a read/write semaphore, return on interruption
719	*
720	* @returns iprt status code.
721	* @retval VINF_SUCCESS on success.
722	* @retval VERR_INTERRUPT if the wait was interrupted.
723	* @retval VERR_INVALID_HANDLE if hRWSem is invalid.
724	*
725	* @param hRWSem Handle to the read/write semaphore.
726	* @param cMillies The number of milliseconds to wait.
727	*/
728	RTDECL(int) RTSemRWRequestReadNoResume(RTSEMRW hRWSem, RTMSINTERVAL cMillies);
729
730	/**
731	* Debug version of RTSemRWRequestRead that tracks the location.
732	*
733	* @returns iprt status code.
734	* @retval VINF_SUCCESS on success.
735	* @retval VERR_INTERRUPT if the wait was interrupted.
736	* @retval VERR_INVALID_HANDLE if hRWSem is invalid.
737	*
738	* @param hRWSem Handle to the read/write semaphore.
739	* @param cMillies The number of milliseconds to wait.
740	* @param uId Some kind of locking location ID. Typically a
741	* return address up the stack. Optional (0).
742	* @param pszFile The file where the lock is being acquired from.
743	* Optional.
744	* @param iLine The line number in that file. Optional (0).
745	* @param pszFunction The functionn where the lock is being acquired
746	* from. Optional.
747	*/
748	RTDECL(int) RTSemRWRequestReadDebug(RTSEMRW hRWSem, RTMSINTERVAL cMillies, RTHCUINTPTR uId, RT_SRC_POS_DECL);
749
750	/**
751	* Debug version of RTSemRWRequestWriteNoResume that tracks the location.
752	*
753	* @returns iprt status code.
754	* @retval VINF_SUCCESS on success.
755	* @retval VERR_INTERRUPT if the wait was interrupted.
756	* @retval VERR_INVALID_HANDLE if hRWSem is invalid.
757	*
758	* @param hRWSem Handle to the read/write semaphore.
759	* @param cMillies The number of milliseconds to wait.
760	* @param uId Some kind of locking location ID. Typically a
761	* return address up the stack. Optional (0).
762	* @param pszFile The file where the lock is being acquired from.
763	* Optional.
764	* @param iLine The line number in that file. Optional (0).
765	* @param pszFunction The functionn where the lock is being acquired
766	* from. Optional.
767	*/
768	RTDECL(int) RTSemRWRequestReadNoResumeDebug(RTSEMRW hRWSem, RTMSINTERVAL cMillies, RTHCUINTPTR uId, RT_SRC_POS_DECL);
769
770	/**
771	* Release read access to a read/write semaphore.
772	*
773	* @returns iprt status code.
774	* @param hRWSem Handle to the read/write semaphore. It goes
775	* without saying that caller must own read
776	* privileges to the semaphore.
777	*/
778	RTDECL(int) RTSemRWReleaseRead(RTSEMRW hRWSem);
779
780	/**
781	* Request write access to a read/write semaphore, resume on interruption.
782	*
783	* @returns iprt status code.
784	* @retval VINF_SUCCESS on success.
785	* @retval VERR_DEADLOCK if the caller owned the read lock.
786	* @retval VERR_INVALID_HANDLE if hRWSem is invalid.
787	*
788	* @param hRWSem Handle to the read/write semaphore.
789	* @param cMillies The number of milliseconds to wait.
790	*/
791	RTDECL(int) RTSemRWRequestWrite(RTSEMRW hRWSem, RTMSINTERVAL cMillies);
792
793	/**
794	* Request write access to a read/write semaphore, return on interruption.
795	*
796	* @returns iprt status code.
797	* @retval VINF_SUCCESS on success.
798	* @retval VERR_INTERRUPT if the wait was interrupted.
799	* @retval VERR_DEADLOCK if the caller owned the read lock.
800	* @retval VERR_INVALID_HANDLE if hRWSem is invalid.
801	*
802	* @param hRWSem Handle to the read/write semaphore.
803	* @param cMillies The number of milliseconds to wait.
804	*/
805	RTDECL(int) RTSemRWRequestWriteNoResume(RTSEMRW hRWSem, RTMSINTERVAL cMillies);
806
807	/**
808	* Debug version of RTSemRWRequestWrite that tracks the location.
809	*
810	* @returns IPRT status code, see RTSemRWRequestWrite.
811	* @param hRWSem Handle to the read/write semaphore.
812	* @param cMillies The number of milliseconds to wait.
813	* @param uId Some kind of locking location ID. Typically a
814	* return address up the stack. Optional (0).
815	* @param pszFile The file where the lock is being acquired from.
816	* Optional.
817	* @param iLine The line number in that file. Optional (0).
818	* @param pszFunction The functionn where the lock is being acquired
819	* from. Optional.
820	*/
821	RTDECL(int) RTSemRWRequestWriteDebug(RTSEMRW hRWSem, RTMSINTERVAL cMillies, RTHCUINTPTR uId, RT_SRC_POS_DECL);
822
823	/**
824	* Debug version of RTSemRWRequestWriteNoResume that tracks the location.
825	*
826	* @returns IPRT status code, see RTSemRWRequestWriteNoResume.
827	* @param hRWSem Handle to the read/write semaphore.
828	* @param cMillies The number of milliseconds to wait.
829	* @param uId Some kind of locking location ID. Typically a
830	* return address up the stack. Optional (0).
831	* @param pszFile The file where the lock is being acquired from.
832	* Optional.
833	* @param iLine The line number in that file. Optional (0).
834	* @param pszFunction The functionn where the lock is being acquired
835	* from. Optional.
836	*/
837	RTDECL(int) RTSemRWRequestWriteNoResumeDebug(RTSEMRW hRWSem, RTMSINTERVAL cMillies, RTHCUINTPTR uId, RT_SRC_POS_DECL);
838
839	/**
840	* Release write access to a read/write semaphore.
841	*
842	* @returns iprt status code.
843	* @param hRWSem Handle to the read/write semaphore. Goes
844	* without saying that caller must have write
845	* access to the semaphore.
846	*/
847	RTDECL(int) RTSemRWReleaseWrite(RTSEMRW hRWSem);
848
849	/**
850	* Checks if the caller is the exclusive semaphore owner.
851	*
852	* @returns true / false accoringly.
853	* @param hRWSem Handle to the read/write semaphore.
854	*/
855	RTDECL(bool) RTSemRWIsWriteOwner(RTSEMRW hRWSem);
856
857	/**
858	* Checks if the caller is one of the read owners of the sempahore.
859	*
860	* @note !CAUTION! This API doesn't work reliably if lock validation isn't
861	* enabled. Meaning, the answer is not trustworhty unless
862	* RT_LOCK_STRICT or RTSEMRW_STRICT was defined at build time. Also,
863	* make sure you do not use RTSEMRW_FLAGS_NO_LOCK_VAL when creating
864	* the semaphore. And finally, if you used a locking class, don't
865	* disable deadlock detection by setting cMsMinDeadlock to
866	* RT_INDEFINITE_WAIT.
867	*
868	* In short, only use this for assertions.
869	*
870	* @returns true if reader, false if not.
871	* @param hRWSem Handle to the read/write semaphore.
872	* @param fWannaHear What you'd like to hear when lock validation is
873	* not available. (For avoiding asserting all over
874	* the place.)
875	*/
876	RTDECL(bool) RTSemRWIsReadOwner(RTSEMRW hRWSem, bool fWannaHear);
877
878	/**
879	* Gets the write recursion count.
880	*
881	* @returns The write recursion count (0 if bad semaphore handle).
882	* @param hRWSem Handle to the read/write semaphore.
883	*/
884	RTDECL(uint32_t) RTSemRWGetWriteRecursion(RTSEMRW hRWSem);
885
886	/**
887	* Gets the read recursion count of the current writer.
888	*
889	* @returns The read recursion count (0 if bad semaphore handle).
890	* @param hRWSem Handle to the read/write semaphore.
891	*/
892	RTDECL(uint32_t) RTSemRWGetWriterReadRecursion(RTSEMRW hRWSem);
893
894	/**
895	* Gets the current number of reads.
896	*
897	* This includes all read recursions, so it might be higher than the number of
898	* read owners. It does not include reads done by the current writer.
899	*
900	* @returns The read count (0 if bad semaphore handle).
901	* @param hRWSem Handle to the read/write semaphore.
902	*/
903	RTDECL(uint32_t) RTSemRWGetReadCount(RTSEMRW hRWSem);
904
905	/* Strict build: Remap the four request calls to the debug versions. */
906	#ifdef RT_STRICT
907	# ifdef ___iprt_asm_h
908	# define RTSemRWRequestRead(pCritSect, cMillies) RTSemRWRequestReadDebug((pCritSect), (cMillies), (uintptr_t)ASMReturnAddress(), RT_SRC_POS)
909	# define RTSemRWRequestReadNoResume(pCritSect, cMillies) RTSemRWRequestReadNoResumeDebug((pCritSect), (cMillies), (uintptr_t)ASMReturnAddress(), RT_SRC_POS)
910	# define RTSemRWRequestWrite(pCritSect, cMillies) RTSemRWRequestWriteDebug((pCritSect), (cMillies), (uintptr_t)ASMReturnAddress(), RT_SRC_POS)
911	# define RTSemRWRequestWriteNoResume(pCritSect, cMillies) RTSemRWRequestWriteNoResumeDebug((pCritSect), (cMillies), (uintptr_t)ASMReturnAddress(), RT_SRC_POS)
912	# else
913	# define RTSemRWRequestRead(pCritSect, cMillies) RTSemRWRequestReadDebug((pCritSect), (cMillies), 0, RT_SRC_POS)
914	# define RTSemRWRequestReadNoResume(pCritSect, cMillies) RTSemRWRequestReadNoResumeDebug((pCritSect), (cMillies), 0, RT_SRC_POS)
915	# define RTSemRWRequestWrite(pCritSect, cMillies) RTSemRWRequestWriteDebug((pCritSect), (cMillies), 0, RT_SRC_POS)
916	# define RTSemRWRequestWriteNoResume(pCritSect, cMillies) RTSemRWRequestWriteNoResumeDebug((pCritSect), (cMillies), 0, RT_SRC_POS)
917	# endif
918	#endif
919
920	/* Strict lock order: Automatically classify locks by init location. */
921	#if defined(RT_LOCK_STRICT_ORDER) && defined(IN_RING3)
922	# define RTSemRWCreate(phSemRW) \
923	RTSemRWCreateEx((phSemRW), 0 /fFlags/, \
924	RTLockValidatorClassForSrcPos(RT_SRC_POS, NULL), \
925	RTLOCKVAL_SUB_CLASS_NONE, NULL)
926	#endif
927
928	/** @} */
929
930
931	/** @defgroup grp_rt_sems_pingpong RTSemPingPong - Ping-Pong Construct
932	*
933	* Serialization of a two way communication.
934	*
935	* @{ */
936
937	/**
938	* Ping-pong speaker
939	*/
940	typedef enum RTPINGPONGSPEAKER
941	{
942	/** Not initialized. */
943	RTPINGPONGSPEAKER_UNINITIALIZE = 0,
944	/** Ping is speaking, Pong is waiting. */
945	RTPINGPONGSPEAKER_PING,
946	/** Pong is signaled, Ping is waiting. */
947	RTPINGPONGSPEAKER_PONG_SIGNALED,
948	/** Pong is speaking, Ping is waiting. */
949	RTPINGPONGSPEAKER_PONG,
950	/** Ping is signaled, Pong is waiting. */
951	RTPINGPONGSPEAKER_PING_SIGNALED,
952	/** Hack to ensure that it's at least 32-bits wide. */
953	RTPINGPONGSPEAKER_HACK = 0x7fffffff
954	} RTPINGPONGSPEAKER;
955
956	/**
957	* Ping-Pong construct.
958	*
959	* Two threads, one saying Ping and the other saying Pong. The construct
960	* makes sure they don't speak out of turn and that they can wait and poll
961	* on the conversation.
962	*/
963	typedef struct RTPINGPONG
964	{
965	/** The semaphore the Ping thread waits on. */
966	RTSEMEVENT Ping;
967	/** The semaphore the Pong thread waits on. */
968	RTSEMEVENT Pong;
969	/** The current speaker. */
970	volatile RTPINGPONGSPEAKER enmSpeaker;
971	#if HC_ARCH_BITS == 64
972	/** Padding the structure to become a multiple of sizeof(RTHCPTR). */
973	uint32_t u32Padding;
974	#endif
975	} RTPINGPONG;
976	/** Pointer to Ping-Pong construct. */
977	typedef RTPINGPONG *PRTPINGPONG;
978
979	/**
980	* Init a Ping-Pong construct.
981	*
982	* @returns iprt status code.
983	* @param pPP Pointer to the ping-pong structure which needs initialization.
984	*/
985	RTDECL(int) RTSemPingPongInit(PRTPINGPONG pPP);
986
987	/**
988	* Deletes a Ping-Pong construct.
989	*
990	* @returns iprt status code.
991	* @param pPP Pointer to the ping-pong structure which is to be destroyed.
992	* (I.e. put into uninitialized state.)
993	*/
994	RTDECL(int) RTSemPingPongDelete(PRTPINGPONG pPP);
995
996	/**
997	* Signals the pong thread in a ping-pong construct. (I.e. sends ping.)
998	* This is called by the ping thread.
999	*
1000	* @returns iprt status code.
1001	* @param pPP Pointer to the ping-pong structure to ping.
1002	*/
1003	RTDECL(int) RTSemPing(PRTPINGPONG pPP);
1004
1005	/**
1006	* Signals the ping thread in a ping-pong construct. (I.e. sends pong.)
1007	* This is called by the pong thread.
1008	*
1009	* @returns iprt status code.
1010	* @param pPP Pointer to the ping-pong structure to pong.
1011	*/
1012	RTDECL(int) RTSemPong(PRTPINGPONG pPP);
1013
1014	/**
1015	* Wait function for the ping thread.
1016	*
1017	* @returns iprt status code.
1018	* Will not return VERR_INTERRUPTED.
1019	* @param pPP Pointer to the ping-pong structure to wait on.
1020	* @param cMillies Number of milliseconds to wait.
1021	*/
1022	RTDECL(int) RTSemPingWait(PRTPINGPONG pPP, RTMSINTERVAL cMillies);
1023
1024	/**
1025	* Wait function for the pong thread.
1026	*
1027	* @returns iprt status code.
1028	* Will not return VERR_INTERRUPTED.
1029	* @param pPP Pointer to the ping-pong structure to wait on.
1030	* @param cMillies Number of milliseconds to wait.
1031	*/
1032	RTDECL(int) RTSemPongWait(PRTPINGPONG pPP, RTMSINTERVAL cMillies);
1033
1034
1035	/**
1036	* Checks if the pong thread is speaking.
1037	*
1038	* @returns true / false.
1039	* @param pPP Pointer to the ping-pong structure.
1040	* @remark This is NOT the same as !RTSemPongIsSpeaker().
1041	*/
1042	DECLINLINE(bool) RTSemPingIsSpeaker(PRTPINGPONG pPP)
1043	{
1044	RTPINGPONGSPEAKER enmSpeaker = pPP->enmSpeaker;
1045	return enmSpeaker == RTPINGPONGSPEAKER_PING;
1046	}
1047
1048
1049	/**
1050	* Checks if the pong thread is speaking.
1051	*
1052	* @returns true / false.
1053	* @param pPP Pointer to the ping-pong structure.
1054	* @remark This is NOT the same as !RTSemPingIsSpeaker().
1055	*/
1056	DECLINLINE(bool) RTSemPongIsSpeaker(PRTPINGPONG pPP)
1057	{
1058	RTPINGPONGSPEAKER enmSpeaker = pPP->enmSpeaker;
1059	return enmSpeaker == RTPINGPONGSPEAKER_PONG;
1060	}
1061
1062
1063	/**
1064	* Checks whether the ping thread should wait.
1065	*
1066	* @returns true / false.
1067	* @param pPP Pointer to the ping-pong structure.
1068	* @remark This is NOT the same as !RTSemPongShouldWait().
1069	*/
1070	DECLINLINE(bool) RTSemPingShouldWait(PRTPINGPONG pPP)
1071	{
1072	RTPINGPONGSPEAKER enmSpeaker = pPP->enmSpeaker;
1073	return enmSpeaker == RTPINGPONGSPEAKER_PONG
1074	\|\| enmSpeaker == RTPINGPONGSPEAKER_PONG_SIGNALED
1075	\|\| enmSpeaker == RTPINGPONGSPEAKER_PING_SIGNALED;
1076	}
1077
1078
1079	/**
1080	* Checks whether the pong thread should wait.
1081	*
1082	* @returns true / false.
1083	* @param pPP Pointer to the ping-pong structure.
1084	* @remark This is NOT the same as !RTSemPingShouldWait().
1085	*/
1086	DECLINLINE(bool) RTSemPongShouldWait(PRTPINGPONG pPP)
1087	{
1088	RTPINGPONGSPEAKER enmSpeaker = pPP->enmSpeaker;
1089	return enmSpeaker == RTPINGPONGSPEAKER_PING
1090	\|\| enmSpeaker == RTPINGPONGSPEAKER_PING_SIGNALED
1091	\|\| enmSpeaker == RTPINGPONGSPEAKER_PONG_SIGNALED;
1092	}
1093
1094	/** @} */
1095
1096
1097	/** @defgroup grp_rt_sems_xroads RTSemXRoads - Crossroads
1098	*
1099	* The crossroads semaphore is intended to prevent two classes of incompatible
1100	* events from occuring simultaneously, like south/north bound traffic and
1101	* west/east bound traffic at a 4-way junction.
1102	*
1103	* @remarks In order to simplify the implementation, the current flow is always
1104	* given priority. So, it won't work at all well when busy!
1105	*
1106	* @remarks "XRoads" is used as a name because it is briefer than "crossroads"
1107	* and it slightly stresses that is a 4 way crossing to the users of
1108	* American English.
1109	* @{
1110	*/
1111
1112	/**
1113	* Creates a crossroads semaphore.
1114	*
1115	* @returns IPRT status code.
1116	*
1117	* @param phXRoads Where to return the handle to the newly created
1118	* crossroads semaphore.
1119	*/
1120	RTDECL(int) RTSemXRoadsCreate(PRTSEMXROADS phXRoads);
1121
1122	/**
1123	* Destroys a crossroads semaphore.
1124	*
1125	* @returns IPRT status code.
1126	*
1127	* @param hXRoads Handle to the crossroads semaphore that is to be
1128	* destroyed. NIL_RTSEMXROADS is quitetly ignored
1129	* (VINF_SUCCESS).
1130	*/
1131	RTDECL(int) RTSemXRoadsDestroy(RTSEMXROADS hXRoads);
1132
1133	/**
1134	* Enter the crossroads from the south or north.
1135	*
1136	* (Coupled with RTSemXRoadsNSLeave.)
1137	*
1138	* @returns IPRT status code.
1139	* @param hXRoads Handle to the crossroads semaphore.
1140	*/
1141	RTDECL(int) RTSemXRoadsNSEnter(RTSEMXROADS hXRoads);
1142
1143	/**
1144	* Leave the crossroads to the north or south.
1145	*
1146	* (Coupled with RTSemXRoadsNSEnter.)
1147	*
1148	* @returns IPRT status code.
1149	* @param hXRoads Handle to the crossroads semaphore.
1150	*/
1151	RTDECL(int) RTSemXRoadsNSLeave(RTSEMXROADS hXRoads);
1152
1153	/**
1154	* Leave the crossroads from the east or west.
1155	*
1156	* (Coupled with RTSemXRoadsEWLeave.)
1157	*
1158	* @returns IPRT status code.
1159	* @param hXRoads Handle to the crossroads semaphore.
1160	*/
1161	RTDECL(int) RTSemXRoadsEWEnter(RTSEMXROADS hXRoads);
1162
1163	/**
1164	* Leave the crossroads to the west or east.
1165	*
1166	* (Coupled with RTSemXRoadsEWEnter.)
1167	*
1168	* @returns IPRT status code.
1169	* @param hXRoads Handle to the crossroads semaphore.
1170	*/
1171	RTDECL(int) RTSemXRoadsEWLeave(RTSEMXROADS hXRoads);
1172
1173	/** @} */
1174
1175	/** @} */
1176
1177	RT_C_DECLS_END
1178
1179	#endif
1180

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source: vbox/trunk/include/iprt/semaphore.h@ 31155

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