added @implemented and @unimplemented notes to the cc through fs directories of ntoskrnl
[reactos.git] / reactos / ntoskrnl / ex / fmutex.c
1 /*
2 * ReactOS kernel
3 * Copyright (C) 1998, 1999, 2000, 2001 ReactOS Team
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18 */
19 /* $Id: fmutex.c,v 1.19 2003/07/10 06:27:13 royce Exp $
20 *
21 * PROJECT: ReactOS kernel
22 * FILE: ntoskrnl/ex/fmutex.c
23 * PURPOSE: Implements fast mutexes
24 * PROGRAMMER: David Welch (welch@cwcom.net)
25 * PORTABILITY: Checked.
26 * UPDATE HISTORY:
27 * Created 22/05/98
28 */
29
30 /* INCLUDES *****************************************************************/
31
32 #include <ddk/ntddk.h>
33
34 #include <internal/debug.h>
35
36 /* FUNCTIONS *****************************************************************/
37
38 /*
39 * @implemented
40 */
41 VOID FASTCALL
42 ExAcquireFastMutexUnsafe(PFAST_MUTEX FastMutex)
43 {
44 assert(FastMutex->Owner != KeGetCurrentThread());
45 InterlockedIncrement((LONG *)&FastMutex->Contention);
46 while (InterlockedExchange(&FastMutex->Count, 0) == 0)
47 {
48 KeWaitForSingleObject(&FastMutex->Event,
49 Executive,
50 KernelMode,
51 FALSE,
52 NULL);
53 }
54 InterlockedDecrement((LONG *)&FastMutex->Contention);
55 FastMutex->Owner = KeGetCurrentThread();
56 }
57
58 /*
59 * @implemented
60 */
61 VOID FASTCALL
62 ExReleaseFastMutexUnsafe(PFAST_MUTEX FastMutex)
63 {
64 assert(FastMutex->Owner == KeGetCurrentThread());
65 FastMutex->Owner = NULL;
66 if (FastMutex->Contention > 0)
67 {
68 KeSetEvent(&FastMutex->Event, 0, FALSE);
69 }
70 InterlockedExchange(&FastMutex->Count, 1);
71 }
72
73 /* EOF */