1 /* Plain recursive mutexes (native Windows implementation).
2 Copyright (C) 2005-2021 Free Software Foundation, Inc.
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 3, or (at your option)
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, see <https://www.gnu.org/licenses/>. */
17 /* Written by Bruno Haible <bruno@clisp.org>, 2005.
18 Based on GCC's gthr-win32.h. */
23 #include "windows-recmutex.h"
28 glwthread_recmutex_init (glwthread_recmutex_t *mutex)
32 InitializeCriticalSection (&mutex->lock);
33 mutex->guard.done = 1;
37 glwthread_recmutex_lock (glwthread_recmutex_t *mutex)
39 if (!mutex->guard.done)
41 if (InterlockedIncrement (&mutex->guard.started) == 0)
42 /* This thread is the first one to need this mutex. Initialize it. */
43 glwthread_recmutex_init (mutex);
46 /* Don't let mutex->guard.started grow and wrap around. */
47 InterlockedDecrement (&mutex->guard.started);
48 /* Yield the CPU while waiting for another thread to finish
49 initializing this mutex. */
50 while (!mutex->guard.done)
55 DWORD self = GetCurrentThreadId ();
56 if (mutex->owner != self)
58 EnterCriticalSection (&mutex->lock);
61 if (++(mutex->depth) == 0) /* wraparound? */
71 glwthread_recmutex_trylock (glwthread_recmutex_t *mutex)
73 if (!mutex->guard.done)
75 if (InterlockedIncrement (&mutex->guard.started) == 0)
76 /* This thread is the first one to need this mutex. Initialize it. */
77 glwthread_recmutex_init (mutex);
80 /* Don't let mutex->guard.started grow and wrap around. */
81 InterlockedDecrement (&mutex->guard.started);
82 /* Let another thread finish initializing this mutex, and let it also
88 DWORD self = GetCurrentThreadId ();
89 if (mutex->owner != self)
91 if (!TryEnterCriticalSection (&mutex->lock))
95 if (++(mutex->depth) == 0) /* wraparound? */
105 glwthread_recmutex_unlock (glwthread_recmutex_t *mutex)
107 if (mutex->owner != GetCurrentThreadId ())
109 if (mutex->depth == 0)
111 if (--(mutex->depth) == 0)
114 LeaveCriticalSection (&mutex->lock);
120 glwthread_recmutex_destroy (glwthread_recmutex_t *mutex)
122 if (mutex->owner != 0)
124 DeleteCriticalSection (&mutex->lock);
125 mutex->guard.done = 0;