BOOST_LOG_API bool once_block_sentry::enter_once_block() const
{
AcquireSRWLockExclusive(&g_OnceBlockMutex);
once_block_flag volatile& flag = m_Flag;
while (flag.status != once_block_flag::initialized)
{
if (flag.status == once_block_flag::uninitialized)
{
flag.status = once_block_flag::being_initialized;
ReleaseSRWLockExclusive(&g_OnceBlockMutex);
// Invoke the initializer block
return false;
}
else
{
while (flag.status == once_block_flag::being_initialized)
{
BOOST_VERIFY(SleepConditionVariableSRW(
&g_OnceBlockCond, &g_OnceBlockMutex, INFINITE, 0));
}
}
}
ReleaseSRWLockExclusive(&g_OnceBlockMutex);
return true;
}
void qemu_cond_wait_impl(QemuCond *cond, QemuMutex *mutex, const char *file, const int line)
{
assert(cond->initialized);
trace_qemu_mutex_unlock(mutex, file, line);
SleepConditionVariableSRW(&cond->var, &mutex->lock, INFINITE, 0);
trace_qemu_mutex_locked(mutex, file, line);
}
// -------------------------------------------------------------------------------------- FUNCTION
// -------------------------------------------------------------------------------------- FUNCTION
void Monitor::Wait(XR_IN xr::Core::Mutex & mutex) const
{
if (SleepConditionVariableSRW((CONDITION_VARIABLE*)&mCondition, mutex.UnderlyingSystemObject(), INFINITE, 0) == FALSE)
{
uint32_t err = (uint32_t)GetLastError();
XR_ASSERT_ALWAYS_EQ_FM(err, ERROR_TIMEOUT, "SleepConditionVariableSRW Error 0x%8.8" XR_UINT32_PRINTX "!", err);
}
}
bool wait() {
BOOL result = SleepConditionVariableSRW( &condition, &lock, INFINITE, 0 );
bool ret = false;
if( result == TRUE ) {
down();
ReleaseSRWLockExclusive( &lock );
ret = true;
}
return ret;
}
BOOL ConsumeElement(int nThreadNum, int nRequestNum, HWND hWndLB) {
// Get access to the queue to consume a new element
AcquireSRWLockShared(&g_srwLock);
// Fall asleep until there is something to read.
// Check if, while it was asleep,
// it was not decided that the thread should stop
while (g_q.IsEmpty(nThreadNum) && !g_fShutdown) {
// There was not a readable element
AddText(hWndLB, TEXT("[%d] Nothing to process"), nThreadNum);
// The queue is empty
// --> Wait until a writer adds a new element to read
// and come back with the lock acquired in shared mode
SleepConditionVariableSRW(&g_cvReadyToConsume, &g_srwLock,
INFINITE, CONDITION_VARIABLE_LOCKMODE_SHARED);
}
// When thread is exiting, the lock should be released for writer
// and readers should be signaled through the condition variable
if (g_fShutdown) {
// Show that the current thread is exiting
AddText(hWndLB, TEXT("[%d] bye bye"), nThreadNum);
// Another writer thread might still be blocked on the lock
// --> release it before exiting
ReleaseSRWLockShared(&g_srwLock);
// Notify other readers that it is time to exit
// --> release readers
WakeConditionVariable(&g_cvReadyToConsume);
return(FALSE);
}
// Get the first new element
CQueue::ELEMENT e;
// Note: No need to test the return value since IsEmpty
// returned FALSE
g_q.GetNewElement(nThreadNum, e);
// No need to keep the lock any longer
ReleaseSRWLockShared(&g_srwLock);
// Show result of consuming the element
AddText(hWndLB, TEXT("[%d] Processing %d:%d"),
nThreadNum, e.m_nThreadNum, e.m_nRequestNum);
// A free slot is now available for writer threads to produce
// --> wake up a writer thread
WakeConditionVariable(&g_cvReadyToProduce);
return(TRUE);
}
_EXP_IMPL void __cdecl Event::wait()
{
AcquireSRWLockExclusive(reinterpret_cast<PSRWLOCK>(&m_lock));
while (!m_isSet)
{
SleepConditionVariableSRW(reinterpret_cast<PCONDITION_VARIABLE>(&m_cond), reinterpret_cast<PSRWLOCK>(&m_lock),
INFINITE, 0);
}
ReleaseSRWLockExclusive(reinterpret_cast<PSRWLOCK>(&m_lock));
}
int __bctbx_WIN_cond_wait(bctbx_cond_t* hCond, bctbx_mutex_t * hMutex)
{
#ifdef BCTBX_WINDOWS_DESKTOP
//gulp: this is not very atomic ! bug here ?
__bctbx_WIN_mutex_unlock(hMutex);
WaitForSingleObject(*hCond, INFINITE);
__bctbx_WIN_mutex_lock(hMutex);
#else
SleepConditionVariableSRW(hCond, hMutex, INFINITE, 0);
#endif
return 0;
}
int condvar_wait(struct condvar_handle *condvar, struct mutex_handle *mutex)
{
struct condvar_priv *priv = (struct condvar_priv *)condvar->priv;
struct mutex_priv *mpriv = (struct mutex_priv *)mutex->priv;
if (!SleepConditionVariableSRW(&priv->cond, &mpriv->lock, INFINITE, 0))
{
return GetLastError();
}
return 0;
}
DWORD QueuePut (QUEUE_OBJECT *q, PVOID msg, DWORD msize, DWORD MaxWait)
{
AcquireSRWLockExclusive (&q->qGuard);
if (q->msgArray == NULL) return 1; /* Queue has been destroyed */
while (QueueFull (q))
{
if (!SleepConditionVariableSRW(&q->qNf, &q->qGuard, INFINITE, 0))
ReportError(_T("QueuePut failed. SleepConditionVariableCS."), 1, TRUE);
}
/* Put the message in the queue */
QueueInsert (q, msg, msize);
/* Signal that the queue is not empty as we've inserted a message */
WakeConditionVariable (&q->qNe);
ReleaseSRWLockExclusive (&q->qGuard);
return 0;
}
DWORD QueueGet (QUEUE_OBJECT *q, PVOID msg, DWORD msize, DWORD MaxWait)
{
AcquireSRWLockExclusive (&q->qGuard);
if (q->msgArray == NULL) return 1; /* Queue has been destroyed */
while (QueueEmpty (q))
{
if (!SleepConditionVariableSRW (&q->qNe, &q->qGuard, INFINITE, 0))
ReportError(_T("QueueGet failed. SleepConditionVariableCS."), 1, TRUE);
}
/* remove the message from the queue */
QueueRemove (q, msg, msize);
/* Signal that the queue is not full as we've removed a message */
WakeConditionVariable (&q->qNf);
ReleaseSRWLockExclusive (&q->qGuard);
return 0;
}
DWORD WINAPI WriterThread(PVOID pvParam) {
int nThreadNum = PtrToUlong(pvParam);
HWND hWndLB = GetDlgItem(g_hWnd, IDC_CLIENTS);
for (int nRequestNum = 1; !g_fShutdown; nRequestNum++) {
CQueue::ELEMENT e = { nThreadNum, nRequestNum };
// Require access for writing
AcquireSRWLockExclusive(&g_srwLock);
// If the queue is full, fall asleep as long as the condition variable
// is not signaled
// Note: During the wait for acquiring the lock,
// a stop might have been received
if (g_q.IsFull() & !g_fShutdown) {
// No more room in the queue
AddText(hWndLB, TEXT("[%d] Queue is full: impossible to add %d"),
nThreadNum, nRequestNum);
// --> Need to wait for a reader to empty a slot before acquiring
// the lock again
SleepConditionVariableSRW(&g_cvReadyToProduce, &g_srwLock,
INFINITE, 0);
}
// Other writer threads might still be blocked on the lock
// --> Release the lock and notify the remaining writer threads to quit
if (g_fShutdown) {
// Show that the current thread is exiting
AddText(hWndLB, TEXT("[%d] bye bye"), nThreadNum);
// No need to keep the lock any longer
ReleaseSRWLockExclusive(&g_srwLock);
// Signal other blocked writers threads that it is time to exit
WakeAllConditionVariable(&g_cvReadyToProduce);
// Bye bye
return(0);
} else {
// Add the new ELEMENT into the queue
g_q.AddElement(e);
// Show result of processing element
AddText(hWndLB, TEXT("[%d] Adding %d"), nThreadNum, nRequestNum);
// No need to keep the lock any longer
ReleaseSRWLockExclusive(&g_srwLock);
// Signal reader threads that there is an element to consume
WakeAllConditionVariable(&g_cvReadyToConsume);
// Wait before adding a new element
Sleep(1500);
}
}
// Show that the current thread is exiting
AddText(hWndLB, TEXT("[%d] bye bye"), nThreadNum);
return(0);
}
// A function responsible for releasing a SlimReadWriter lock and putting the calling thread to sleep.
inline bool ConditionVariable::sleep( SRWLOCK& slim_read_writer_lock , const DWORD milliseconds , bool shared )
{
return ( SleepConditionVariableSRW(&_variable,&slim_read_writer_lock,milliseconds, ( shared ? CONDITION_VARIABLE_LOCKMODE_SHARED : 0 ) ) > FALSE ? true : false );
};
