semaphore.h@ 25908

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1	/** @file
2	* IPRT - Semaphore.
3	*/
4
5	/*
6	* Copyright (C) 2006-2007 Sun Microsystems, Inc.
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	* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
26	* Clara, CA 95054 USA or visit http://www.sun.com if you need
27	* additional information or have any questions.
28	*/
29
30	#ifndef ___iprt_semaphore_h
31	#define ___iprt_semaphore_h
32
33	#include <iprt/cdefs.h>
34	#include <iprt/types.h>
35	#if defined(RT_LOCK_STRICT_ORDER) && defined(IN_RING3)
36	# include <iprt/lockvalidator.h>
37	#endif
38
39
40	RT_C_DECLS_BEGIN
41
42	/** @defgroup grp_rt_sems RTSem - Semaphores
43	*
44	* This module implements all kinds of event and mutex semaphores; in addition
45	* to these, IPRT implements "critical sections", which are fast recursive
46	* mutexes (see @ref grp_rt_critsect ). C++ users may find @ref grp_rt_lock
47	* interesting.
48	*
49	* @ingroup grp_rt
50	* @{
51	*/
52
53
54	/** @defgroup grp_rt_sems_event RTSemEvent - Single Release Event Semaphores
55	*
56	* Event semaphores can be used for inter-thread communication when one thread
57	* wants to notify another thread that something happened. A thread can block
58	* ("wait") on an event semaphore until it is signalled by another thread; see
59	* RTSemEventCreate, RTSemEventSignal and RTSemEventWait.
60	*
61	* @{ */
62
63	/**
64	* Create an event semaphore.
65	*
66	* @returns iprt status code.
67	* @param phEventSem Where to store the handle to the newly created
68	* event semaphore.
69	*/
70	RTDECL(int) RTSemEventCreate(PRTSEMEVENT phEventSem);
71
72	/**
73	* Create an event semaphore.
74	*
75	* @returns iprt status code.
76	* @param phEventSem Where to store the handle to the newly created
77	* event semaphore.
78	* @param fFlags Flags, any combination of the
79	* RTSEMEVENT_FLAGS_XXX \#defines.
80	* @param hClass The class (no reference consumed). Since we
81	* don't do order checks on event semaphores, the
82	* use of the class is limited to controlling the
83	* timeout threshold for deadlock detection.
84	* @param pszNameFmt Name format string for the lock validator,
85	* optional (NULL). Max length is 32 bytes.
86	* @param ... Format string arguments.
87	*/
88	RTDECL(int) RTSemEventCreateEx(PRTSEMEVENT phEventSem, uint32_t fFlags, RTLOCKVALCLASS hClass, const char *pszNameFmt, ...);
89
90	/** @name RTSemMutexCreateEx flags
91	* @{ */
92	/** Disables lock validation. */
93	#define RTSEMEVENT_FLAGS_NO_LOCK_VAL UINT32_C(0x00000001)
94	/** @} */
95
96	/**
97	* Destroy an event semaphore.
98	*
99	* @returns iprt status code.
100	* @param hEventSem Handle of the event sempahore. NIL_RTSEMEVENT
101	* is quitely ignored (VINF_SUCCESS).
102	*/
103	RTDECL(int) RTSemEventDestroy(RTSEMEVENT hEventSem);
104
105	/**
106	* Signal an event semaphore.
107	*
108	* The event semaphore will be signaled and automatically reset after exactly
109	* one thread have successfully returned from RTSemEventWait() after
110	* waiting/polling on that semaphore.
111	*
112	* @returns iprt status code.
113	* @param hEventSem The event semaphore to signal.
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	RTDECL(int) RTSemEventMultiSignal(RTSEMEVENTMULTI hEventMultiSem);
236
237	/**
238	* Resets an event multi semaphore to non-signaled state.
239	*
240	* @returns iprt status code.
241	* @param hEventMultiSem The multiple release event sempahore.
242	*/
243	RTDECL(int) RTSemEventMultiReset(RTSEMEVENTMULTI hEventMultiSem);
244
245	/**
246	* Wait for the event multi semaphore to be signaled, resume on interruption.
247	*
248	* This function will resume if the wait is interrupted by an async
249	* system event (like a unix signal) or similar.
250	*
251	* @returns iprt status code.
252	* Will not return VERR_INTERRUPTED.
253	* @param hEventMultiSem The multiple release event sempahore.
254	* @param cMillies Number of milliseconds to wait.
255	*/
256	RTDECL(int) RTSemEventMultiWait(RTSEMEVENTMULTI hEventMultiSem, RTMSINTERVAL cMillies);
257
258
259	/**
260	* Wait for the event multi semaphore to be signaled, return on interruption.
261	*
262	* This function will not resume the wait if interrupted.
263	*
264	* @returns iprt status code.
265	* @param hEventMultiSem The multiple release event sempahore.
266	* @param cMillies Number of milliseconds to wait.
267	*/
268	RTDECL(int) RTSemEventMultiWaitNoResume(RTSEMEVENTMULTI hEventMultiSem, RTMSINTERVAL cMillies);
269
270	/**
271	* Sets the signaller thread to one specific thread.
272	*
273	* This is only used for validating usage and deadlock detection. When used
274	* after calls to RTSemEventAddSignaller, the specified thread will be the only
275	* signalling thread.
276	*
277	* @param hEventMultiSem The multiple release event semaphore.
278	* @param hThread The thread that will signal it. Pass
279	* NIL_RTTHREAD to indicate that there is no
280	* special signalling thread.
281	*/
282	RTDECL(void) RTSemEventMultiSetSignaller(RTSEMEVENTMULTI hEventMultiSem, RTTHREAD hThread);
283
284	/**
285	* To add more signalling threads.
286	*
287	* First call RTSemEventSetSignaller then add further threads with this.
288	*
289	* @param hEventMultiSem The multiple release event semaphore.
290	* @param hThread The thread that will signal it. NIL_RTTHREAD is
291	* not accepted.
292	*/
293	RTDECL(void) RTSemEventMultiAddSignaller(RTSEMEVENTMULTI hEventMultiSem, RTTHREAD hThread);
294
295	/**
296	* To remove a signalling thread.
297	*
298	* Reverts work done by RTSemEventAddSignaller and RTSemEventSetSignaller.
299	*
300	* @param hEventMultiSem The multiple release event semaphore.
301	* @param hThread A previously added thread.
302	*/
303	RTDECL(void) RTSemEventMultiRemoveSignaller(RTSEMEVENTMULTI hEventMultiSem, RTTHREAD hThread);
304
305	/** @} */
306
307
308	/** @defgroup grp_rt_sems_mutex RTSemMutex - Mutex semaphores.
309	*
310	* Mutex semaphores protect a section of code or data to which access must be
311	* exclusive. Only one thread can hold access to a critical section at one
312	* time. See RTSemMutexCreate, RTSemMutexRequest and RTSemMutexRelease.
313	*
314	* @remarks These are less efficient than "fast mutexes" and "critical
315	* sections", which IPRT implements as well; see @ref
316	* grp_rt_sems_fast_mutex and @ref grp_rt_critsect .
317	*
318	* @{ */
319
320	/**
321	* Create a mutex semaphore.
322	*
323	* @returns iprt status code.
324	* @param phMutexSem Where to store the mutex semaphore handle.
325	*/
326	RTDECL(int) RTSemMutexCreate(PRTSEMMUTEX phMutexSem);
327
328	/**
329	* Creates a read/write semaphore.
330	*
331	* @returns iprt status code.
332	* @param phRWSem Where to store the handle to the newly created
333	* RW semaphore.
334	* @param fFlags Flags, any combination of the
335	* RTSEMMUTEX_FLAGS_XXX \#defines.
336	* @param hClass The class (no reference consumed). If NIL, no
337	* lock order validation will be performed on this
338	* lock.
339	* @param uSubClass The sub-class. This is used to define lock
340	* order within a class. RTLOCKVAL_SUB_CLASS_NONE
341	* is the recommended value here.
342	* @param pszNameFmt Name format string for the lock validator,
343	* optional (NULL). Max length is 32 bytes.
344	* @param ... Format string arguments.
345	*/
346	RTDECL(int) RTSemMutexCreateEx(PRTSEMMUTEX phMutexSem, uint32_t fFlags,
347	RTLOCKVALCLASS hClass, uint32_t uSubClass, const char *pszNameFmt, ...);
348
349	/** @name RTSemMutexCreateEx flags
350	* @{ */
351	/** Disables lock validation. */
352	#define RTSEMMUTEX_FLAGS_NO_LOCK_VAL UINT32_C(0x00000001)
353	/** @} */
354
355
356	/**
357	* Destroy a mutex semaphore.
358	*
359	* @returns iprt status code.
360	* @param hMutexSem The mutex semaphore to destroy. NIL is quitely
361	* ignored (VINF_SUCCESS).
362	*/
363	RTDECL(int) RTSemMutexDestroy(RTSEMMUTEX hMutexSem);
364
365	/**
366	* Changes the lock validator sub-class of the mutex semaphore.
367	*
368	* It is recommended to try make sure that nobody is using this sempahore while
369	* changing the value.
370	*
371	* @returns The old sub-class. RTLOCKVAL_SUB_CLASS_INVALID is returns if the
372	* lock validator isn't compiled in or either of the parameters are
373	* invalid.
374	* @param hMutexSem The handle to the mutex semaphore.
375	* @param uSubClass The new sub-class value.
376	*/
377	RTDECL(uint32_t) RTSemMutexSetSubClass(RTSEMMUTEX hMutexSem, uint32_t uSubClass);
378
379	/**
380	* Request ownership of a mutex semaphore, resume on interruption.
381	*
382	* This function will resume if the wait is interrupted by an async
383	* system event (like a unix signal) or similar.
384	*
385	* The same thread may request a mutex semaphore multiple times,
386	* a nested counter is kept to make sure it's released on the right
387	* RTSemMutexRelease() call.
388	*
389	* @returns iprt status code.
390	* Will not return VERR_INTERRUPTED.
391	* @param hMutexSem The mutex semaphore to request ownership over.
392	* @param cMillies The number of milliseconds to wait.
393	*/
394	RTDECL(int) RTSemMutexRequest(RTSEMMUTEX hMutexSem, RTMSINTERVAL cMillies);
395
396	/**
397	* Request ownership of a mutex semaphore, return on interruption.
398	*
399	* This function will not resume the wait if interrupted.
400	*
401	* The same thread may request a mutex semaphore multiple times,
402	* a nested counter is kept to make sure it's released on the right
403	* RTSemMutexRelease() call.
404	*
405	* @returns iprt status code.
406	* @param hMutexSem The mutex semaphore to request ownership over.
407	* @param cMillies The number of milliseconds to wait.
408	*/
409	RTDECL(int) RTSemMutexRequestNoResume(RTSEMMUTEX hMutexSem, RTMSINTERVAL cMillies);
410
411	/**
412	* Debug version of RTSemMutexRequest that tracks the location.
413	*
414	* @returns iprt status code.
415	* Will not return VERR_INTERRUPTED.
416	* @param hMutexSem The mutex semaphore to request ownership over.
417	* @param cMillies The number of milliseconds to wait.
418	* @param uId Some kind of locking location ID. Typically a
419	* return address up the stack. Optional (0).
420	* @param pszFile The file where the lock is being acquired from.
421	* Optional.
422	* @param iLine The line number in that file. Optional (0).
423	* @param pszFunction The functionn where the lock is being acquired
424	* from. Optional.
425	*/
426	RTDECL(int) RTSemMutexRequestDebug(RTSEMMUTEX hMutexSem, RTMSINTERVAL cMillies, RTHCUINTPTR uId, RT_SRC_POS_DECL);
427
428	/**
429	* Debug version of RTSemMutexRequestNoResume that tracks the location.
430	*
431	* @returns iprt status code.
432	* @param hMutexSem The mutex semaphore to request ownership over.
433	* @param cMillies The number of milliseconds to wait.
434	* @param uId Some kind of locking location ID. Typically a
435	* return address up the stack. Optional (0).
436	* @param pszFile The file where the lock is being acquired from.
437	* Optional.
438	* @param iLine The line number in that file. Optional (0).
439	* @param pszFunction The functionn where the lock is being acquired
440	* from. Optional.
441	*/
442	RTDECL(int) RTSemMutexRequestNoResumeDebug(RTSEMMUTEX hMutexSem, RTMSINTERVAL cMillies, RTHCUINTPTR uId, RT_SRC_POS_DECL);
443
444	/**
445	* Release the ownership of a mutex semaphore.
446	*
447	* @returns iprt status code.
448	* @param hMutexSem The mutex to release the ownership of. It goes
449	* without saying the the calling thread must own
450	* it.
451	*/
452	RTDECL(int) RTSemMutexRelease(RTSEMMUTEX hMutexSem);
453
454	/**
455	* Checks if the mutex semaphore is owned or not.
456	*
457	* @returns true if owned, false if not.
458	* @param hMutexSem The mutex semaphore.
459	*/
460	RTDECL(bool) RTSemMutexIsOwned(RTSEMMUTEX hMutexSem);
461
462	/* Strict build: Remap the two request calls to the debug versions. */
463	#ifdef RT_STRICT
464	# ifdef ___iprt_asm_h
465	# define RTSemMutexRequest(pCritSect, cMillies) RTSemMutexRequestDebug((pCritSect), (cMillies), (uintptr_t)ASMReturnAddress(), RT_SRC_POS)
466	# define RTSemMutexRequestNoResume(pCritSect, cMillies) RTSemMutexRequestNoResumeDebug((pCritSect), (cMillies), (uintptr_t)ASMReturnAddress(), RT_SRC_POS)
467	# else
468	# define RTSemMutexRequest(pCritSect, cMillies) RTSemMutexRequestDebug((pCritSect), (cMillies), 0, RT_SRC_POS)
469	# define RTSemMutexRequestNoResume(pCritSect, cMillies) RTSemMutexRequestNoResumeDebug((pCritSect), (cMillies), 0, RT_SRC_POS)
470	# endif
471	#endif
472
473	/* Strict lock order: Automatically classify locks by init location. */
474	#if defined(RT_LOCK_STRICT_ORDER) && defined(IN_RING3)
475	# define RTSemMutexCreate(phMutexSem) \
476	RTSemMutexCreateEx((phMutexSem), 0 /fFlags/, \
477	RTLockValidatorClassForSrcPos(RT_SRC_POS, NULL), \
478	RTLOCKVAL_SUB_CLASS_NONE, NULL)
479	#endif
480
481	/** @} */
482
483
484	/** @defgroup grp_rt_sems_fast_mutex RTSemFastMutex - Fast Mutex Semaphores
485	*
486	* Fast mutexes work like regular mutexes in that they allow only a single
487	* thread access to a critical piece of code or data. As opposed to mutexes,
488	* they require no syscall if the fast mutex is not held (like critical
489	* sections). Unlike critical sections however, they are not recursive.
490	*
491	* @{ */
492
493	/**
494	* Create a fast mutex semaphore.
495	*
496	* @returns iprt status code.
497	* @param phFastMtx Where to store the handle to the newly created
498	* fast mutex semaphore.
499	*
500	* @remarks Fast mutex semaphores are not recursive.
501	*/
502	RTDECL(int) RTSemFastMutexCreate(PRTSEMFASTMUTEX phFastMtx);
503
504	/**
505	* Destroy a fast mutex semaphore.
506	*
507	* @returns iprt status code.
508	* @param hFastMtx Handle to the fast mutex semaphore. NIL is
509	* quietly ignored (VINF_SUCCESS).
510	*/
511	RTDECL(int) RTSemFastMutexDestroy(RTSEMFASTMUTEX hFastMtx);
512
513	/**
514	* Request ownership of a fast mutex semaphore.
515	*
516	* The same thread may request a mutex semaphore multiple times,
517	* a nested counter is kept to make sure it's released on the right
518	* RTSemMutexRelease() call.
519	*
520	* @returns iprt status code.
521	* @param hFastMtx Handle to the fast mutex semaphore.
522	*/
523	RTDECL(int) RTSemFastMutexRequest(RTSEMFASTMUTEX hFastMtx);
524
525	/**
526	* Release the ownership of a fast mutex semaphore.
527	*
528	* @returns iprt status code.
529	* @param hFastMtx Handle to the fast mutex semaphore. It goes
530	* without saying the the calling thread must own
531	* it.
532	*/
533	RTDECL(int) RTSemFastMutexRelease(RTSEMFASTMUTEX hFastMtx);
534
535	/** @} */
536
537
538	/** @defgroup grp_rt_sems_spin_mutex RTSemSpinMutex - Spinning Mutex Semaphores
539	*
540	* A very adaptive variant of mutex semaphore that is tailored for the ring-0
541	* logger.
542	*
543	* @{ */
544
545	/**
546	* Creates a spinning mutex semaphore.
547	*
548	* @returns iprt status code.
549	* @retval VERR_INVALID_PARAMETER on invalid flags.
550	* @retval VERR_NO_MEMORY if out of memory for the semaphore structure and
551	* handle.
552	*
553	* @param phSpinMtx Where to return the handle to the create semaphore.
554	* @param fFlags Flags, see RTSEMSPINMUTEX_FLAGS_XXX.
555	*/
556	RTDECL(int) RTSemSpinMutexCreate(PRTSEMSPINMUTEX phSpinMtx, uint32_t fFlags);
557
558	/** @name RTSemSpinMutexCreate flags.
559	* @{ */
560	/** Always take the semaphore in a IRQ safe way.
561	* (In plain words: always disable interrupts.) */
562	#define RTSEMSPINMUTEX_FLAGS_IRQ_SAFE RT_BIT_32(0)
563	/** Mask of valid flags. */
564	#define RTSEMSPINMUTEX_FLAGS_VALID_MASK UINT32_C(0x00000001)
565	/** @} */
566
567	/**
568	* Destroys a spinning mutex semaphore.
569	*
570	* @returns iprt status code.
571	* @retval VERR_INVALID_HANDLE (or crash) if the handle is invalid. (NIL will
572	* not cause this status.)
573	*
574	* @param hSpinMtx The semaphore handle. NIL_RTSEMSPINMUTEX is ignored
575	* quietly (VINF_SUCCESS).
576	*/
577	RTDECL(int) RTSemSpinMutexDestroy(RTSEMSPINMUTEX hSpinMtx);
578
579	/**
580	* Request the spinning mutex semaphore.
581	*
582	* This may block if the context we're called in allows this. If not it will
583	* spin. If called in an interrupt context, we will only spin if the current
584	* owner isn't interrupted. Also, on some systems it is not always possible to
585	* wake up blocking threads in all contexts, so, which will either be indicated
586	* by returning VERR_SEM_BAD_CONTEXT or by temporarily switching the semaphore
587	* into pure spinlock state.
588	*
589	* Preemption will be disabled upon return. IRQs may also be disabled.
590	*
591	* @returns iprt status code.
592	* @retval VERR_SEM_BAD_CONTEXT if the context it's called in isn't suitable
593	* for releasing it if someone is sleeping on it.
594	* @retval VERR_SEM_DESTROYED if destroyed.
595	* @retval VERR_SEM_NESTED if held by the caller. Asserted.
596	* @retval VERR_INVALID_HANDLE if the handle is invalid. Asserted
597	*
598	* @param hSpinMtx The semaphore handle.
599	*/
600	RTDECL(int) RTSemSpinMutexRequest(RTSEMSPINMUTEX hSpinMtx);
601
602	/**
603	* Like RTSemSpinMutexRequest but it won't block or spin if the semaphore is
604	* held by someone else.
605	*
606	* @returns iprt status code.
607	* @retval VERR_SEM_BUSY if held by someone else.
608	* @retval VERR_SEM_DESTROYED if destroyed.
609	* @retval VERR_SEM_NESTED if held by the caller. Asserted.
610	* @retval VERR_INVALID_HANDLE if the handle is invalid. Asserted
611	*
612	* @param hSpinMtx The semaphore handle.
613	*/
614	RTDECL(int) RTSemSpinMutexTryRequest(RTSEMSPINMUTEX hSpinMtx);
615
616	/**
617	* Releases the semaphore previously acquired by RTSemSpinMutexRequest or
618	* RTSemSpinMutexTryRequest.
619	*
620	* @returns iprt status code.
621	* @retval VERR_SEM_DESTROYED if destroyed.
622	* @retval VERR_NOT_OWNER if not owner. Asserted.
623	* @retval VERR_INVALID_HANDLE if the handle is invalid. Asserted.
624	*
625	* @param hSpinMtx The semaphore handle.
626	*/
627	RTDECL(int) RTSemSpinMutexRelease(RTSEMSPINMUTEX hSpinMtx);
628
629	/** @} */
630
631
632	/** @defgroup grp_rt_sem_rw RTSemRW - Read / Write Semaphores
633	*
634	* Read/write semaphores are a fancier version of mutexes in that they grant
635	* read access to the protected data to several threads at the same time but
636	* allow only one writer at a time. This can make code scale better at the
637	* expense of slightly more overhead in mutex management.
638	*
639	* @{ */
640
641	/**
642	* Creates a read/write semaphore.
643	*
644	* @returns iprt status code.
645	* @param phRWSem Where to store the handle to the newly created
646	* RW semaphore.
647	*/
648	RTDECL(int) RTSemRWCreate(PRTSEMRW phRWSem);
649
650	/**
651	* Creates a read/write semaphore.
652	*
653	* @returns iprt status code.
654	* @param phRWSem Where to store the handle to the newly created
655	* RW semaphore.
656	* @param fFlags Flags, any combination of the RTSEMRW_FLAGS_XXX
657	* \#defines.
658	* @param hClass The class (no reference consumed). If NIL, no
659	* lock order validation will be performed on this
660	* lock.
661	* @param uSubClass The sub-class. This is used to define lock
662	* order within a class. RTLOCKVAL_SUB_CLASS_NONE
663	* is the recommended value here.
664	* @param pszNameFmt Name format string for the lock validator,
665	* optional (NULL). Max length is 32 bytes.
666	* @param ... Format string arguments.
667	*/
668	RTDECL(int) RTSemRWCreateEx(PRTSEMRW phRWSem, uint32_t fFlags,
669	RTLOCKVALCLASS hClass, uint32_t uSubClass, const char *pszNameFmt, ...);
670
671	/** @name RTSemRWCreateEx flags
672	* @{ */
673	/** Disables lock validation. */
674	#define RTSEMRW_FLAGS_NO_LOCK_VAL UINT32_C(0x00000001)
675	/** @} */
676
677	/**
678	* Destroys a read/write semaphore.
679	*
680	* @returns iprt status code.
681	* @param hRWSem Handle to the read/write semaphore. NIL is
682	* quitly ignored (VINF_SUCCESS).
683	*/
684	RTDECL(int) RTSemRWDestroy(RTSEMRW hRWSem);
685
686	/**
687	* Changes the lock validator sub-class of the read/write semaphore.
688	*
689	* It is recommended to try make sure that nobody is using this sempahore while
690	* changing the value.
691	*
692	* @returns The old sub-class. RTLOCKVAL_SUB_CLASS_INVALID is returns if the
693	* lock validator isn't compiled in or either of the parameters are
694	* invalid.
695	* @param hRWSem Handle to the read/write semaphore.
696	* @param uSubClass The new sub-class value.
697	*/
698	RTDECL(uint32_t) RTSemRWSetSubClass(RTSEMRW hRWSem, uint32_t uSubClass);
699
700	/**
701	* Request read access to a read/write semaphore, resume on interruption
702	*
703	* @returns iprt status code.
704	* @retval VINF_SUCCESS on success.
705	* @retval VERR_INTERRUPT if the wait was interrupted.
706	* @retval VERR_INVALID_HANDLE if hRWSem is invalid.
707	*
708	* @param hRWSem Handle to the read/write semaphore.
709	* @param cMillies The number of milliseconds to wait.
710	*/
711	RTDECL(int) RTSemRWRequestRead(RTSEMRW hRWSem, RTMSINTERVAL cMillies);
712
713	/**
714	* Request read access to a read/write semaphore, return on interruption
715	*
716	* @returns iprt status code.
717	* @retval VINF_SUCCESS on success.
718	* @retval VERR_INTERRUPT if the wait was interrupted.
719	* @retval VERR_INVALID_HANDLE if hRWSem is invalid.
720	*
721	* @param hRWSem Handle to the read/write semaphore.
722	* @param cMillies The number of milliseconds to wait.
723	*/
724	RTDECL(int) RTSemRWRequestReadNoResume(RTSEMRW hRWSem, RTMSINTERVAL cMillies);
725
726	/**
727	* Debug version of RTSemRWRequestRead that tracks the location.
728	*
729	* @returns iprt status code.
730	* @retval VINF_SUCCESS on success.
731	* @retval VERR_INTERRUPT if the wait was interrupted.
732	* @retval VERR_INVALID_HANDLE if hRWSem is invalid.
733	*
734	* @param hRWSem Handle to the read/write semaphore.
735	* @param cMillies The number of milliseconds to wait.
736	* @param uId Some kind of locking location ID. Typically a
737	* return address up the stack. Optional (0).
738	* @param pszFile The file where the lock is being acquired from.
739	* Optional.
740	* @param iLine The line number in that file. Optional (0).
741	* @param pszFunction The functionn where the lock is being acquired
742	* from. Optional.
743	*/
744	RTDECL(int) RTSemRWRequestReadDebug(RTSEMRW hRWSem, RTMSINTERVAL cMillies, RTHCUINTPTR uId, RT_SRC_POS_DECL);
745
746	/**
747	* Debug version of RTSemRWRequestWriteNoResume that tracks the location.
748	*
749	* @returns iprt status code.
750	* @retval VINF_SUCCESS on success.
751	* @retval VERR_INTERRUPT if the wait was interrupted.
752	* @retval VERR_INVALID_HANDLE if hRWSem is invalid.
753	*
754	* @param hRWSem Handle to the read/write semaphore.
755	* @param cMillies The number of milliseconds to wait.
756	* @param uId Some kind of locking location ID. Typically a
757	* return address up the stack. Optional (0).
758	* @param pszFile The file where the lock is being acquired from.
759	* Optional.
760	* @param iLine The line number in that file. Optional (0).
761	* @param pszFunction The functionn where the lock is being acquired
762	* from. Optional.
763	*/
764	RTDECL(int) RTSemRWRequestReadNoResumeDebug(RTSEMRW hRWSem, RTMSINTERVAL cMillies, RTHCUINTPTR uId, RT_SRC_POS_DECL);
765
766	/**
767	* Release read access to a read/write semaphore.
768	*
769	* @returns iprt status code.
770	* @param hRWSem Handle to the read/write semaphore. It goes
771	* without saying that caller must own read
772	* privileges to the semaphore.
773	*/
774	RTDECL(int) RTSemRWReleaseRead(RTSEMRW hRWSem);
775
776	/**
777	* Request write access to a read/write semaphore, resume on interruption.
778	*
779	* @returns iprt status code.
780	* @retval VINF_SUCCESS on success.
781	* @retval VERR_DEADLOCK if the caller owned the read lock.
782	* @retval VERR_INVALID_HANDLE if hRWSem is invalid.
783	*
784	* @param hRWSem Handle to the read/write semaphore.
785	* @param cMillies The number of milliseconds to wait.
786	*/
787	RTDECL(int) RTSemRWRequestWrite(RTSEMRW hRWSem, RTMSINTERVAL cMillies);
788
789	/**
790	* Request write access to a read/write semaphore, return on interruption.
791	*
792	* @returns iprt status code.
793	* @retval VINF_SUCCESS on success.
794	* @retval VERR_INTERRUPT if the wait was interrupted.
795	* @retval VERR_DEADLOCK if the caller owned the read lock.
796	* @retval VERR_INVALID_HANDLE if hRWSem is invalid.
797	*
798	* @param hRWSem Handle to the read/write semaphore.
799	* @param cMillies The number of milliseconds to wait.
800	*/
801	RTDECL(int) RTSemRWRequestWriteNoResume(RTSEMRW hRWSem, RTMSINTERVAL cMillies);
802
803	/**
804	* Debug version of RTSemRWRequestWrite that tracks the location.
805	*
806	* @returns IPRT status code, see RTSemRWRequestWrite.
807	* @param hRWSem Handle to the read/write semaphore.
808	* @param cMillies The number of milliseconds to wait.
809	* @param uId Some kind of locking location ID. Typically a
810	* return address up the stack. Optional (0).
811	* @param pszFile The file where the lock is being acquired from.
812	* Optional.
813	* @param iLine The line number in that file. Optional (0).
814	* @param pszFunction The functionn where the lock is being acquired
815	* from. Optional.
816	*/
817	RTDECL(int) RTSemRWRequestWriteDebug(RTSEMRW hRWSem, RTMSINTERVAL cMillies, RTHCUINTPTR uId, RT_SRC_POS_DECL);
818
819	/**
820	* Debug version of RTSemRWRequestWriteNoResume that tracks the location.
821	*
822	* @returns IPRT status code, see RTSemRWRequestWriteNoResume.
823	* @param hRWSem Handle to the read/write semaphore.
824	* @param cMillies The number of milliseconds to wait.
825	* @param uId Some kind of locking location ID. Typically a
826	* return address up the stack. Optional (0).
827	* @param pszFile The file where the lock is being acquired from.
828	* Optional.
829	* @param iLine The line number in that file. Optional (0).
830	* @param pszFunction The functionn where the lock is being acquired
831	* from. Optional.
832	*/
833	RTDECL(int) RTSemRWRequestWriteNoResumeDebug(RTSEMRW hRWSem, RTMSINTERVAL cMillies, RTHCUINTPTR uId, RT_SRC_POS_DECL);
834
835	/**
836	* Release write access to a read/write semaphore.
837	*
838	* @returns iprt status code.
839	* @param hRWSem Handle to the read/write semaphore. Goes
840	* without saying that caller must have write
841	* access to the semaphore.
842	*/
843	RTDECL(int) RTSemRWReleaseWrite(RTSEMRW hRWSem);
844
845	/**
846	* Checks if the caller is the exclusive semaphore owner.
847	*
848	* @returns true / false accoringly.
849	* @param hRWSem Handle to the read/write semaphore.
850	*/
851	RTDECL(bool) RTSemRWIsWriteOwner(RTSEMRW hRWSem);
852
853	/**
854	* Checks if the caller is one of the read owners of the sempahore.
855	*
856	* @note !CAUTION! This API doesn't work reliably if lock validation isn't
857	* enabled. Meaning, the answer is not trustworhty unless
858	* RT_LOCK_STRICT or RTSEMRW_STRICT was defined at build time. Also,
859	* make sure you do not use RTSEMRW_FLAGS_NO_LOCK_VAL when creating
860	* the semaphore. And finally, if you used a locking class, don't
861	* disable deadlock detection by setting cMsMinDeadlock to
862	* RT_INDEFINITE_WAIT.
863	*
864	* In short, only use this for assertions.
865	*
866	* @returns true if reader, false if not.
867	* @param hRWSem Handle to the read/write semaphore.
868	* @param fWannaHear What you'd like to hear when lock validation is
869	* not available. (For avoiding asserting all over
870	* the place.)
871	*/
872	RTDECL(bool) RTSemRWIsReadOwner(RTSEMRW hRWSem, bool fWannaHear);
873
874	/**
875	* Gets the write recursion count.
876	*
877	* @returns The write recursion count (0 if bad semaphore handle).
878	* @param hRWSem Handle to the read/write semaphore.
879	*/
880	RTDECL(uint32_t) RTSemRWGetWriteRecursion(RTSEMRW hRWSem);
881
882	/**
883	* Gets the read recursion count of the current writer.
884	*
885	* @returns The read recursion count (0 if bad semaphore handle).
886	* @param hRWSem Handle to the read/write semaphore.
887	*/
888	RTDECL(uint32_t) RTSemRWGetWriterReadRecursion(RTSEMRW hRWSem);
889
890	/**
891	* Gets the current number of reads.
892	*
893	* This includes all read recursions, so it might be higher than the number of
894	* read owners. It does not include reads done by the current writer.
895	*
896	* @returns The read count (0 if bad semaphore handle).
897	* @param hRWSem Handle to the read/write semaphore.
898	*/
899	RTDECL(uint32_t) RTSemRWGetReadCount(RTSEMRW hRWSem);
900
901	/* Strict build: Remap the four request calls to the debug versions. */
902	#ifdef RT_STRICT
903	# ifdef ___iprt_asm_h
904	# define RTSemRWRequestRead(pCritSect, cMillies) RTSemRWRequestReadDebug((pCritSect), (cMillies), (uintptr_t)ASMReturnAddress(), RT_SRC_POS)
905	# define RTSemRWRequestReadNoResume(pCritSect, cMillies) RTSemRWRequestReadNoResumeDebug((pCritSect), (cMillies), (uintptr_t)ASMReturnAddress(), RT_SRC_POS)
906	# define RTSemRWRequestWrite(pCritSect, cMillies) RTSemRWRequestWriteDebug((pCritSect), (cMillies), (uintptr_t)ASMReturnAddress(), RT_SRC_POS)
907	# define RTSemRWRequestWriteNoResume(pCritSect, cMillies) RTSemRWRequestWriteNoResumeDebug((pCritSect), (cMillies), (uintptr_t)ASMReturnAddress(), RT_SRC_POS)
908	# else
909	# define RTSemRWRequestRead(pCritSect, cMillies) RTSemRWRequestReadDebug((pCritSect), (cMillies), 0, RT_SRC_POS)
910	# define RTSemRWRequestReadNoResume(pCritSect, cMillies) RTSemRWRequestReadNoResumeDebug((pCritSect), (cMillies), 0, RT_SRC_POS)
911	# define RTSemRWRequestWrite(pCritSect, cMillies) RTSemRWRequestWriteDebug((pCritSect), (cMillies), 0, RT_SRC_POS)
912	# define RTSemRWRequestWriteNoResume(pCritSect, cMillies) RTSemRWRequestWriteNoResumeDebug((pCritSect), (cMillies), 0, RT_SRC_POS)
913	# endif
914	#endif
915
916	/* Strict lock order: Automatically classify locks by init location. */
917	#if defined(RT_LOCK_STRICT_ORDER) && defined(IN_RING3)
918	# define RTSemRWCreate(phSemRW) \
919	RTSemRWCreateEx((phSemRW), 0 /fFlags/, \
920	RTLockValidatorClassForSrcPos(RT_SRC_POS, NULL), \
921	RTLOCKVAL_SUB_CLASS_NONE, NULL)
922	#endif
923
924	/** @} */
925
926
927	/** @defgroup grp_rt_sems_pingpong RTSemPingPong - Ping-Pong Construct
928	*
929	* Serialization of a two way communication.
930	*
931	* @{ */
932
933	/**
934	* Ping-pong speaker
935	*/
936	typedef enum RTPINGPONGSPEAKER
937	{
938	/** Not initialized. */
939	RTPINGPONGSPEAKER_UNINITIALIZE = 0,
940	/** Ping is speaking, Pong is waiting. */
941	RTPINGPONGSPEAKER_PING,
942	/** Pong is signaled, Ping is waiting. */
943	RTPINGPONGSPEAKER_PONG_SIGNALED,
944	/** Pong is speaking, Ping is waiting. */
945	RTPINGPONGSPEAKER_PONG,
946	/** Ping is signaled, Pong is waiting. */
947	RTPINGPONGSPEAKER_PING_SIGNALED,
948	/** Hack to ensure that it's at least 32-bits wide. */
949	RTPINGPONGSPEAKER_HACK = 0x7fffffff
950	} RTPINGPONGSPEAKER;
951
952	/**
953	* Ping-Pong construct.
954	*
955	* Two threads, one saying Ping and the other saying Pong. The construct
956	* makes sure they don't speak out of turn and that they can wait and poll
957	* on the conversation.
958	*/
959	typedef struct RTPINGPONG
960	{
961	/** The semaphore the Ping thread waits on. */
962	RTSEMEVENT Ping;
963	/** The semaphore the Pong thread waits on. */
964	RTSEMEVENT Pong;
965	/** The current speaker. */
966	volatile RTPINGPONGSPEAKER enmSpeaker;
967	#if HC_ARCH_BITS == 64
968	/** Padding the structure to become a multiple of sizeof(RTHCPTR). */
969	uint32_t u32Padding;
970	#endif
971	} RTPINGPONG;
972	/** Pointer to Ping-Pong construct. */
973	typedef RTPINGPONG *PRTPINGPONG;
974
975	/**
976	* Init a Ping-Pong construct.
977	*
978	* @returns iprt status code.
979	* @param pPP Pointer to the ping-pong structure which needs initialization.
980	*/
981	RTDECL(int) RTSemPingPongInit(PRTPINGPONG pPP);
982
983	/**
984	* Deletes a Ping-Pong construct.
985	*
986	* @returns iprt status code.
987	* @param pPP Pointer to the ping-pong structure which is to be destroyed.
988	* (I.e. put into uninitialized state.)
989	*/
990	RTDECL(int) RTSemPingPongDelete(PRTPINGPONG pPP);
991
992	/**
993	* Signals the pong thread in a ping-pong construct. (I.e. sends ping.)
994	* This is called by the ping thread.
995	*
996	* @returns iprt status code.
997	* @param pPP Pointer to the ping-pong structure to ping.
998	*/
999	RTDECL(int) RTSemPing(PRTPINGPONG pPP);
1000
1001	/**
1002	* Signals the ping thread in a ping-pong construct. (I.e. sends pong.)
1003	* This is called by the pong thread.
1004	*
1005	* @returns iprt status code.
1006	* @param pPP Pointer to the ping-pong structure to pong.
1007	*/
1008	RTDECL(int) RTSemPong(PRTPINGPONG pPP);
1009
1010	/**
1011	* Wait function for the ping thread.
1012	*
1013	* @returns iprt status code.
1014	* Will not return VERR_INTERRUPTED.
1015	* @param pPP Pointer to the ping-pong structure to wait on.
1016	* @param cMillies Number of milliseconds to wait.
1017	*/
1018	RTDECL(int) RTSemPingWait(PRTPINGPONG pPP, RTMSINTERVAL cMillies);
1019
1020	/**
1021	* Wait function for the pong thread.
1022	*
1023	* @returns iprt status code.
1024	* Will not return VERR_INTERRUPTED.
1025	* @param pPP Pointer to the ping-pong structure to wait on.
1026	* @param cMillies Number of milliseconds to wait.
1027	*/
1028	RTDECL(int) RTSemPongWait(PRTPINGPONG pPP, RTMSINTERVAL cMillies);
1029
1030
1031	/**
1032	* Checks if the pong thread is speaking.
1033	*
1034	* @returns true / false.
1035	* @param pPP Pointer to the ping-pong structure.
1036	* @remark This is NOT the same as !RTSemPongIsSpeaker().
1037	*/
1038	DECLINLINE(bool) RTSemPingIsSpeaker(PRTPINGPONG pPP)
1039	{
1040	RTPINGPONGSPEAKER enmSpeaker = pPP->enmSpeaker;
1041	return enmSpeaker == RTPINGPONGSPEAKER_PING;
1042	}
1043
1044
1045	/**
1046	* Checks if the pong thread is speaking.
1047	*
1048	* @returns true / false.
1049	* @param pPP Pointer to the ping-pong structure.
1050	* @remark This is NOT the same as !RTSemPingIsSpeaker().
1051	*/
1052	DECLINLINE(bool) RTSemPongIsSpeaker(PRTPINGPONG pPP)
1053	{
1054	RTPINGPONGSPEAKER enmSpeaker = pPP->enmSpeaker;
1055	return enmSpeaker == RTPINGPONGSPEAKER_PONG;
1056	}
1057
1058
1059	/**
1060	* Checks whether the ping thread should wait.
1061	*
1062	* @returns true / false.
1063	* @param pPP Pointer to the ping-pong structure.
1064	* @remark This is NOT the same as !RTSemPongShouldWait().
1065	*/
1066	DECLINLINE(bool) RTSemPingShouldWait(PRTPINGPONG pPP)
1067	{
1068	RTPINGPONGSPEAKER enmSpeaker = pPP->enmSpeaker;
1069	return enmSpeaker == RTPINGPONGSPEAKER_PONG
1070	\|\| enmSpeaker == RTPINGPONGSPEAKER_PONG_SIGNALED
1071	\|\| enmSpeaker == RTPINGPONGSPEAKER_PING_SIGNALED;
1072	}
1073
1074
1075	/**
1076	* Checks whether the pong thread should wait.
1077	*
1078	* @returns true / false.
1079	* @param pPP Pointer to the ping-pong structure.
1080	* @remark This is NOT the same as !RTSemPingShouldWait().
1081	*/
1082	DECLINLINE(bool) RTSemPongShouldWait(PRTPINGPONG pPP)
1083	{
1084	RTPINGPONGSPEAKER enmSpeaker = pPP->enmSpeaker;
1085	return enmSpeaker == RTPINGPONGSPEAKER_PING
1086	\|\| enmSpeaker == RTPINGPONGSPEAKER_PING_SIGNALED
1087	\|\| enmSpeaker == RTPINGPONGSPEAKER_PONG_SIGNALED;
1088	}
1089
1090	/** @} */
1091
1092
1093	/** @defgroup grp_rt_sems_xroads RTSemXRoads - Crossroads
1094	*
1095	* The crossroads semaphore is intended to prevent two classes of incompatible
1096	* events from occuring simultaneously, like south/north bound traffic and
1097	* west/east bound traffic at a 4-way junction.
1098	*
1099	* @remarks In order to simplify the implementation, the current flow is always
1100	* given priority. So, it won't work at all well when busy!
1101	*
1102	* @remarks "XRoads" is used as a name because it is briefer than "crossroads"
1103	* and it slightly stresses that is a 4 way crossing to the users of
1104	* American English.
1105	* @{
1106	*/
1107
1108	/**
1109	* Creates a crossroads semaphore.
1110	*
1111	* @returns IPRT status code.
1112	*
1113	* @param phXRoads Where to return the handle to the newly created
1114	* crossroads semaphore.
1115	*/
1116	RTDECL(int) RTSemXRoadsCreate(PRTSEMXROADS phXRoads);
1117
1118	/**
1119	* Destroys a crossroads semaphore.
1120	*
1121	* @returns IPRT status code.
1122	*
1123	* @param hXRoads Handle to the crossroads semaphore that is to be
1124	* destroyed. NIL_RTSEMXROADS is quitetly ignored
1125	* (VINF_SUCCESS).
1126	*/
1127	RTDECL(int) RTSemXRoadsDestroy(RTSEMXROADS hXRoads);
1128
1129	/**
1130	* Enter the crossroads from the south or north.
1131	*
1132	* (Coupled with RTSemXRoadsNSLeave.)
1133	*
1134	* @returns IPRT status code.
1135	* @param hXRoads Handle to the crossroads semaphore.
1136	*/
1137	RTDECL(int) RTSemXRoadsNSEnter(RTSEMXROADS hXRoads);
1138
1139	/**
1140	* Leave the crossroads to the north or south.
1141	*
1142	* (Coupled with RTSemXRoadsNSEnter.)
1143	*
1144	* @returns IPRT status code.
1145	* @param hXRoads Handle to the crossroads semaphore.
1146	*/
1147	RTDECL(int) RTSemXRoadsNSLeave(RTSEMXROADS hXRoads);
1148
1149	/**
1150	* Leave the crossroads from the east or west.
1151	*
1152	* (Coupled with RTSemXRoadsEWLeave.)
1153	*
1154	* @returns IPRT status code.
1155	* @param hXRoads Handle to the crossroads semaphore.
1156	*/
1157	RTDECL(int) RTSemXRoadsEWEnter(RTSEMXROADS hXRoads);
1158
1159	/**
1160	* Leave the crossroads to the west or east.
1161	*
1162	* (Coupled with RTSemXRoadsEWEnter.)
1163	*
1164	* @returns IPRT status code.
1165	* @param hXRoads Handle to the crossroads semaphore.
1166	*/
1167	RTDECL(int) RTSemXRoadsEWLeave(RTSEMXROADS hXRoads);
1168
1169	/** @} */
1170
1171	/** @} */
1172
1173	RT_C_DECLS_END
1174
1175	#endif
1176

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