int CMainDocument::RequestRPC(ASYNC_RPC_REQUEST& request, bool hasPriority) {
std::vector<ASYNC_RPC_REQUEST>::iterator iter;
int retval = 0;
int response = wxID_OK;
wxMutexError mutexErr = wxMUTEX_NO_ERROR;
long delayTimeRemaining, timeToSleep;
bool shown = false;
if (!m_RPCThread) return -1;
if ( (request.rpcType < RPC_TYPE_WAIT_FOR_COMPLETION) ||
(request.rpcType >= NUM_RPC_TYPES) ) {
wxASSERT(false);
return -1;
}
// If we are quitting, cancel any pending RPCs
if (request.which_rpc == RPC_QUIT) {
if (current_rpc_request.isActive) {
RPC_requests.erase(RPC_requests.begin()+1, RPC_requests.end());
} else {
RPC_requests.clear();
}
}
// Check if a duplicate request is already on the queue
for (iter=RPC_requests.begin(); iter!=RPC_requests.end(); iter++) {
if (iter->isSameAs(request)) {
return 0;
}
}
if ((request.rpcType == RPC_TYPE_WAIT_FOR_COMPLETION) && (request.resultPtr == NULL)) {
request.resultPtr = &retval;
}
if (hasPriority) {
// We may want to set hasPriority for some user-initiated events.
// Since the user is waiting, insert this at head of request queue.
// As of 8/14/08, hasPriority is never set true, so hasn't been tested.
iter = RPC_requests.insert(RPC_requests.begin(), request);
} else {
RPC_requests.push_back(request);
}
// Start this RPC if no other RPC is already in progress.
if (RPC_requests.size() == 1) {
// Wait for thread to unlock mutex with m_pRPC_Thread_Condition->Wait()
mutexErr = m_pRPC_Thread_Mutex->Lock(); // Blocks until thread unlocks the mutex
wxASSERT(mutexErr == wxMUTEX_NO_ERROR);
// Make sure activation is an atomic operation
request.isActive = false;
current_rpc_request = request;
current_rpc_request.isActive = true;
m_pRPC_Thread_Condition->Signal(); // Unblock the thread
// m_pRPC_Thread_Condition->Wait() will Lock() the mutex upon receiving Signal(),
// causing it to block again if we still have our lock on the mutex.
mutexErr = m_pRPC_Thread_Mutex->Unlock();
wxASSERT(mutexErr == wxMUTEX_NO_ERROR);
}
// If this is a user-initiated event wait for completion but show
// a dialog allowing the user to cancel.
if (request.rpcType == RPC_TYPE_WAIT_FOR_COMPLETION) {
// TODO: proper handling if a second user request is received while first is pending ??
if (m_bWaitingForRPC) {
wxLogMessage(wxT("Second user RPC request while another was pending"));
wxASSERT(false);
return -1;
}
// Don't show dialog if RPC completes before RPC_WAIT_DLG_DELAY
// or while BOINC is minimized
CBOINCBaseFrame* pFrame = wxGetApp().GetFrame();
wxStopWatch Dlgdelay = wxStopWatch();
m_RPCWaitDlg = new AsyncRPCDlg();
m_bWaitingForRPC = true;
// Allow RPC_WAIT_DLG_DELAY seconds for Demand RPC to complete before
// displaying "Please Wait" dialog, but keep checking for completion.
delayTimeRemaining = RPC_WAIT_DLG_DELAY;
while (true) {
if (delayTimeRemaining >= 0) { // Prevent overflow if minimized for a very long time
delayTimeRemaining = RPC_WAIT_DLG_DELAY - Dlgdelay.Time();
}
if (pFrame) {
shown = pFrame->IsShown();
} else {
shown = false;
}
if (shown) {
if (delayTimeRemaining <= 0) break; // Display the Please Wait dialog
timeToSleep = delayTimeRemaining;
} else {
// Don't show dialog while Manager is minimized, but do
// process events so user can maximize the manager.
//
// NOTE: CBOINCGUIApp::FilterEvent() discards those events
// which might cause posting of more RPC requests while
// we are in this loop, to prevent undesirable recursion.
// Since the manager is minimized, we don't have to worry about
// discarding crucial drawing or command events.
// The filter does allow the the Open Manager menu item from
// the system tray icon and wxEVT_RPC_FINISHED event.
//
timeToSleep = DELAY_WHEN_MINIMIZED; // Allow user to maximize Manager
wxSafeYield(NULL, true);
}
// OnRPCComplete() clears m_bWaitingForRPC if RPC completed
if (! m_bWaitingForRPC) {
return retval;
}
mutexErr = m_pRPC_Request_Mutex->Lock();
wxASSERT(mutexErr == wxMUTEX_NO_ERROR);
// Simulate handling of CRPCFinishedEvent but don't allow any other
// events (so no user activity) to prevent undesirable recursion.
// Since we don't need to filter and discard events, they remain on
// the queue until it is safe to process them.
// Allow RPC thread to run while we wait for it.
if (!current_rpc_request.isActive) {
mutexErr = m_pRPC_Request_Mutex->Unlock();
wxASSERT(mutexErr == wxMUTEX_NO_ERROR);
HandleCompletedRPC();
continue;
}
// Wait for RPC thread to wake us
// This does the following:
// (1) Unlocks the Mutex and puts the main thread to sleep as an atomic operation.
// (2) On Signal from RPC thread: locks Mutex again and wakes the main thread.
m_pRPC_Request_Condition->WaitTimeout(timeToSleep);
mutexErr = m_pRPC_Request_Mutex->Unlock();
wxASSERT(mutexErr == wxMUTEX_NO_ERROR);
}
// Demand RPC has taken longer than RPC_WAIT_DLG_DELAY seconds and
// Manager is not minimized, so display the "Please Wait" dialog
// with a Cancel button. If the RPC does complete while the dialog
// is up, HandleCompletedRPC() will call EndModal with wxID_OK.
//
// NOTE: the Modal dialog permits processing of all events, but
// CBOINCGUIApp::FilterEvent() blocks those events which might cause
// posting of more RPC requests while in this dialog, to prevent
// undesirable recursion.
//
if (m_RPCWaitDlg) {
response = m_RPCWaitDlg->ShowModal();
// Remember time the dialog was closed for use by RunPeriodicRPCs()
m_dtLasAsyncRPCDlgTime = wxDateTime::Now();
if (response != wxID_OK) {
// TODO: If user presses Cancel in Please Wait dialog but request
// has not yet been started, should we just remove it from queue?
// If we make that change, should we also add a separate menu item
// to reset the RPC connection (or does one already exist)?
retval = -1;
// If the RPC continues to get data after we return to
// our caller, it may try to write into a buffer or struct
// which the caller has already deleted. To prevent this,
// we close the socket (disconnect) and kill the RPC thread.
// This is ugly but necessary. We must then reconnect and
// start a new RPC thread.
if (current_rpc_request.isActive) {
current_rpc_request.isActive = false;
rpcClient.close();
RPC_requests.clear();
current_rpc_request.clear();
m_bNeedRefresh = false;
m_bNeedTaskBarRefresh = false;
// We will be reconnected to the same client (if possible) by
// CBOINCDialUpManager::OnPoll() and CNetworkConnection::Poll().
m_pNetworkConnection->SetStateDisconnected();
}
if (response == wxID_EXIT) {
pFrame = wxGetApp().GetFrame();
wxCommandEvent evt(wxEVT_COMMAND_MENU_SELECTED, wxID_EXIT);
s_bSkipExitConfirmation = true;
pFrame->AddPendingEvent(evt);
}
}
if (m_RPCWaitDlg) {
m_RPCWaitDlg->Destroy();
}
m_RPCWaitDlg = NULL;
m_bWaitingForRPC = false;
}
}
return retval;
}
