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authorJörg Frings-Fürst <debian@jff.email>2024-10-20 15:22:21 +0200
committerJörg Frings-Fürst <debian@jff.email>2024-10-20 15:22:21 +0200
commit1d8b9e17ea13630aec475484da09ebba0366f7c8 (patch)
tree0c801f68561bfb0930a4ade80d7ca3a7940887ab /tests/windows-timedmutex.c
parent84e26c587987e8484d55db4165f188b40c09e94b (diff)
parent630f99f29bd31a76d8d24da2975a045452c763ef (diff)
Merge branch 'feature/upstream' into develop
Diffstat (limited to 'tests/windows-timedmutex.c')
-rw-r--r--tests/windows-timedmutex.c265
1 files changed, 265 insertions, 0 deletions
diff --git a/tests/windows-timedmutex.c b/tests/windows-timedmutex.c
new file mode 100644
index 00000000..3833cab1
--- /dev/null
+++ b/tests/windows-timedmutex.c
@@ -0,0 +1,265 @@
+/* Timed mutexes (native Windows implementation).
+ Copyright (C) 2005-2024 Free Software Foundation, Inc.
+
+ This file is free software: you can redistribute it and/or modify
+ it under the terms of the GNU Lesser General Public License as
+ published by the Free Software Foundation; either version 2.1 of the
+ License, or (at your option) any later version.
+
+ This file is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+/* Written by Bruno Haible <bruno@clisp.org>, 2005, 2019.
+ Based on GCC's gthr-win32.h. */
+
+#include <config.h>
+
+/* Specification. */
+#include "windows-timedmutex.h"
+
+#include <errno.h>
+#include <stdlib.h>
+#include <sys/time.h>
+
+/* Don't assume that UNICODE is not defined. */
+#undef CreateEvent
+#define CreateEvent CreateEventA
+
+int
+glwthread_timedmutex_init (glwthread_timedmutex_t *mutex)
+{
+ /* Attempt to allocate an auto-reset event object. */
+ /* CreateEvent
+ <https://docs.microsoft.com/en-us/windows/desktop/api/synchapi/nf-synchapi-createeventa> */
+ HANDLE event = CreateEvent (NULL, FALSE, FALSE, NULL);
+ if (event == INVALID_HANDLE_VALUE)
+ return EAGAIN;
+ mutex->event = event;
+ mutex->owner = 0;
+ InitializeCriticalSection (&mutex->lock);
+ mutex->guard.done = 1;
+ return 0;
+}
+
+int
+glwthread_timedmutex_lock (glwthread_timedmutex_t *mutex)
+{
+ if (!mutex->guard.done)
+ {
+ if (InterlockedIncrement (&mutex->guard.started) == 0)
+ {
+ /* This thread is the first one to need this mutex.
+ Initialize it. */
+ int err = glwthread_timedmutex_init (mutex);
+ if (err != 0)
+ {
+ /* Undo increment. */
+ InterlockedDecrement (&mutex->guard.started);
+ return err;
+ }
+ }
+ else
+ {
+ /* Don't let mutex->guard.started grow and wrap around. */
+ InterlockedDecrement (&mutex->guard.started);
+ /* Yield the CPU while waiting for another thread to finish
+ initializing this mutex. */
+ while (!mutex->guard.done)
+ Sleep (0);
+ }
+ }
+ /* If this thread already owns the mutex, POSIX pthread_mutex_lock() is
+ required to deadlock here. But let's not do that on purpose. */
+ EnterCriticalSection (&mutex->lock);
+ {
+ DWORD self = GetCurrentThreadId ();
+ mutex->owner = self;
+ }
+ return 0;
+}
+
+int
+glwthread_timedmutex_trylock (glwthread_timedmutex_t *mutex)
+{
+ if (!mutex->guard.done)
+ {
+ if (InterlockedIncrement (&mutex->guard.started) == 0)
+ {
+ /* This thread is the first one to need this mutex.
+ Initialize it. */
+ int err = glwthread_timedmutex_init (mutex);
+ if (err != 0)
+ {
+ /* Undo increment. */
+ InterlockedDecrement (&mutex->guard.started);
+ return err;
+ }
+ }
+ else
+ {
+ /* Don't let mutex->guard.started grow and wrap around. */
+ InterlockedDecrement (&mutex->guard.started);
+ /* Let another thread finish initializing this mutex, and let it also
+ lock this mutex. */
+ return EBUSY;
+ }
+ }
+ if (!TryEnterCriticalSection (&mutex->lock))
+ return EBUSY;
+ {
+ DWORD self = GetCurrentThreadId ();
+ /* TryEnterCriticalSection succeeded. This means that the mutex was either
+ previously unlocked (and thus mutex->owner == 0) or previously locked by
+ this thread (and thus mutex->owner == self). Since the mutex is meant to
+ be plain, we need to fail in the latter case. */
+ if (mutex->owner == self)
+ {
+ LeaveCriticalSection (&mutex->lock);
+ return EBUSY;
+ }
+ if (mutex->owner != 0)
+ abort ();
+ mutex->owner = self;
+ }
+ return 0;
+}
+
+int
+glwthread_timedmutex_timedlock (glwthread_timedmutex_t *mutex,
+ const struct timespec *abstime)
+{
+ if (!mutex->guard.done)
+ {
+ if (InterlockedIncrement (&mutex->guard.started) == 0)
+ {
+ /* This thread is the first one to need this mutex.
+ Initialize it. */
+ int err = glwthread_timedmutex_init (mutex);
+ if (err != 0)
+ {
+ /* Undo increment. */
+ InterlockedDecrement (&mutex->guard.started);
+ return err;
+ }
+ }
+ else
+ {
+ /* Don't let mutex->guard.started grow and wrap around. */
+ InterlockedDecrement (&mutex->guard.started);
+ /* Yield the CPU while waiting for another thread to finish
+ initializing this mutex. */
+ while (!mutex->guard.done)
+ Sleep (0);
+ }
+ }
+
+ /* POSIX says:
+ "Under no circumstance shall the function fail with a timeout if
+ the mutex can be locked immediately. The validity of the abstime
+ parameter need not be checked if the mutex can be locked
+ immediately."
+ Therefore start the loop with a TryEnterCriticalSection call. */
+ for (;;)
+ {
+ if (TryEnterCriticalSection (&mutex->lock))
+ break;
+
+ {
+ struct timeval currtime;
+ DWORD timeout;
+ DWORD result;
+
+ gettimeofday (&currtime, NULL);
+
+ /* Wait until another thread signals the event or until the
+ abstime passes. */
+ if (currtime.tv_sec > abstime->tv_sec)
+ timeout = 0;
+ else
+ {
+ unsigned long seconds = abstime->tv_sec - currtime.tv_sec;
+ timeout = seconds * 1000;
+ if (timeout / 1000 != seconds) /* overflow? */
+ timeout = INFINITE;
+ else
+ {
+ long milliseconds =
+ abstime->tv_nsec / 1000000 - currtime.tv_usec / 1000;
+ if (milliseconds >= 0)
+ {
+ timeout += milliseconds;
+ if (timeout < milliseconds) /* overflow? */
+ timeout = INFINITE;
+ }
+ else
+ {
+ if (timeout >= - milliseconds)
+ timeout -= (- milliseconds);
+ else
+ timeout = 0;
+ }
+ }
+ }
+ if (timeout == 0)
+ return ETIMEDOUT;
+
+ /* WaitForSingleObject
+ <https://docs.microsoft.com/en-us/windows/desktop/api/synchapi/nf-synchapi-waitforsingleobject> */
+ result = WaitForSingleObject (mutex->event, timeout);
+ if (result == WAIT_FAILED)
+ abort ();
+ if (result == WAIT_TIMEOUT)
+ return ETIMEDOUT;
+ /* Another thread has just unlocked the mutex. We have good chances at
+ locking it now. */
+ }
+ }
+ {
+ DWORD self = GetCurrentThreadId ();
+ /* TryEnterCriticalSection succeeded. This means that the mutex was either
+ previously unlocked (and thus mutex->owner == 0) or previously locked by
+ this thread (and thus mutex->owner == self). Since the mutex is meant to
+ be plain, it is useful to fail in the latter case. */
+ if (mutex->owner == self)
+ {
+ LeaveCriticalSection (&mutex->lock);
+ return EDEADLK;
+ }
+ if (mutex->owner != 0)
+ abort ();
+ mutex->owner = self;
+ }
+ return 0;
+}
+
+int
+glwthread_timedmutex_unlock (glwthread_timedmutex_t *mutex)
+{
+ if (!mutex->guard.done)
+ return EINVAL;
+ mutex->owner = 0;
+ LeaveCriticalSection (&mutex->lock);
+ /* Notify one of the threads that were waiting with a timeout. */
+ /* SetEvent
+ <https://docs.microsoft.com/en-us/windows/desktop/api/synchapi/nf-synchapi-setevent> */
+ SetEvent (mutex->event);
+ return 0;
+}
+
+int
+glwthread_timedmutex_destroy (glwthread_timedmutex_t *mutex)
+{
+ if (!mutex->guard.done)
+ return EINVAL;
+ DeleteCriticalSection (&mutex->lock);
+ /* CloseHandle
+ <https://docs.microsoft.com/en-us/windows/desktop/api/handleapi/nf-handleapi-closehandle> */
+ CloseHandle (mutex->event);
+ mutex->guard.done = 0;
+ return 0;
+}