bool
CNdasEventPreSubscriber::BeginWaitForConnection()
{
XTLENSURE_RETURN_T(!m_hPipe.IsInvalid() && "Not initialized", false);
XTLENSURE_RETURN_T(!m_hEvent.IsInvalid() && "Not initialized", false);
XTLENSURE_RETURN_T( ResetOverlapped(), false);
BOOL fConnected = ::ConnectNamedPipe(m_hPipe, &m_overlapped);
if (fConnected)
{
XTLENSURE_RETURN_T(::SetEvent(m_hEvent), false);
return true;
}
DWORD error = ::GetLastError();
switch (error)
{
case ERROR_IO_PENDING:
// The overlapped connection in progress
break;
case ERROR_PIPE_CONNECTED:
// client is already connected, signal an event
XTLENSURE_RETURN_T(::SetEvent(m_hEvent), false);
break;
default:
return true;
}
return true;
}
bool
CNdasEventSubscriber::BeginWriteMessage(const NDAS_EVENT_MESSAGE& msg)
{
XTLENSURE_RETURN_T(ResetOverlapped(), false);
const DWORD cbToWrite = sizeof(NDAS_EVENT_MESSAGE);
DWORD cbWritten;
BOOL fSuccess = ::WriteFile(m_hPipe, &msg, cbToWrite, &cbWritten, &m_overlapped);
if (!fSuccess && ::GetLastError() != ERROR_IO_PENDING)
{
return false;
}
return true;
}
bool AsyncIO::asyncWrite(size_t qIdx, const void* buf, size_t length, off_t offset) {
OVERLAPPED& aio = m_queue[qIdx].first;
if (aio.hEvent) {
#ifndef NDEBUG
fprintf(stderr, "WARNING: synchronous kabufuda fallback, check access polling\n");
#endif
_waitForOperation(qIdx);
} else {
aio.hEvent = CreateEvent(nullptr, TRUE, FALSE, nullptr);
}
ResetOverlapped(aio, DWORD(offset));
m_maxBlock = std::max(m_maxBlock, qIdx + 1);
BOOL res = WriteFile(m_fh, buf, length, nullptr, &aio);
return res == TRUE || GetLastError() == ERROR_IO_PENDING;
}
bool
CNdasEventPreSubscriber::Initialize()
{
if (m_hEvent.IsInvalid())
{
m_hEvent = ::CreateEvent(NULL, TRUE, FALSE, NULL);
if (m_hEvent.IsInvalid())
{
return false;
}
}
if (!ResetPipeHandle())
{
return false;
}
XTLENSURE_RETURN_T(ResetOverlapped(), false);
return true;
}
bool
CNdasEventPreSubscriber::ResetPipeHandle()
{
XTLASSERT(m_hPipe.IsInvalid());
XTLENSURE_RETURN_T(ResetOverlapped(), false);
m_hPipe = ::CreateNamedPipe(
PipeName,
PIPE_ACCESS_OUTBOUND | FILE_FLAG_OVERLAPPED,
PIPE_TYPE_MESSAGE | PIPE_READMODE_MESSAGE | PIPE_WAIT,
MaxInstances,
sizeof(NDAS_EVENT_MESSAGE),
0,
NMPWAIT_USE_DEFAULT_WAIT,
NULL);
if (m_hPipe.IsInvalid())
{
return false;
}
return true;
}
