/**
* Unblocks a wait block.
*
* \param WaitBlock A wait block.
*
* \remarks The wait block is in an undefined state after it is
* unblocked. Do not attempt to read any values from it. All relevant
* information should be saved before unblocking the wait block.
*/
__mayRaise FORCEINLINE VOID PhpUnblockQueuedWaitBlock(
__inout PPH_QUEUED_WAIT_BLOCK WaitBlock
)
{
NTSTATUS status;
if (!_interlockedbittestandreset((PLONG)&WaitBlock->Flags, PH_QUEUED_WAITER_SPINNING_SHIFT))
{
if (!NT_SUCCESS(status = NtReleaseKeyedEvent(
PhQueuedLockKeyedEventHandle,
WaitBlock,
FALSE,
NULL
)))
PhRaiseStatus(status);
}
}
/**
* Waits for a wait block to be unblocked.
*
* \param WaitBlock A wait block.
* \param Spin TRUE to spin, FALSE to block immediately.
* \param Timeout A timeout value.
*/
__mayRaise FORCEINLINE NTSTATUS PhpBlockOnQueuedWaitBlock(
__inout PPH_QUEUED_WAIT_BLOCK WaitBlock,
__in BOOLEAN Spin,
__in_opt PLARGE_INTEGER Timeout
)
{
NTSTATUS status;
ULONG i;
if (Spin)
{
PHLIB_INC_STATISTIC(QlBlockSpins);
for (i = PhQueuedLockSpinCount; i != 0; i--)
{
if (!(*(volatile ULONG *)&WaitBlock->Flags & PH_QUEUED_WAITER_SPINNING))
return STATUS_SUCCESS;
YieldProcessor();
}
}
if (_interlockedbittestandreset((PLONG)&WaitBlock->Flags, PH_QUEUED_WAITER_SPINNING_SHIFT))
{
PHLIB_INC_STATISTIC(QlBlockWaits);
status = NtWaitForKeyedEvent(
PhQueuedLockKeyedEventHandle,
WaitBlock,
FALSE,
Timeout
);
// If an error occurred (timeout is not an error), raise an exception
// as it is nearly impossible to recover from this situation.
if (!NT_SUCCESS(status))
PhRaiseStatus(status);
}
else
{
status = STATUS_SUCCESS;
}
return status;
}
inline bool interlocked_bit_test_and_reset(long* x,long bit)
{
return _interlockedbittestandreset(x,bit)!=0;
}
void __cdecl _Atomic_flag_clear(volatile _Atomic_flag_t *_Flag,
memory_order _Order)
{ /* atomically clear flag */
_interlockedbittestandreset(_Flag, 1); /* reset bit 0 */
}
void ReleaseLock()
{
LONG *p = (LONG*)&mutex;
_interlockedbittestandreset(p,0);
}