INT
WINAPI
NSQUERY::LookupServiceNext(
IN DWORD dwControlFlags,
IN OUT LPDWORD lpdwBufferLength,
IN OUT LPWSAQUERYSETW lpqsResults
)
/*++
Routine Description:
//***TODO Fill in description from the spec when it stabilizes.
Arguments:
Return Value:
--*/
{
INT ReturnCode = SOCKET_ERROR;
PNSPROVIDERSTATE NewProvider = NULL;
PNSPROVIDERSTATE ThisProvider = NULL;
again:
if (!m_shutting_down){
//Snapshot the value of m_current_provider and bump up the calls in
//progress counter
EnterCriticalSection(&m_members_guard);
InterlockedIncrement(&m_calls_in_progress);
NewProvider = m_current_provider;
LeaveCriticalSection(&m_members_guard);
if ( !NewProvider )
SetLastError( WSA_E_NO_MORE );
while (NewProvider){
ReturnCode = NewProvider->LookupServiceNext(
dwControlFlags,
lpdwBufferLength,
lpqsResults);
if ((ERROR_SUCCESS == ReturnCode)
||
(WSAEFAULT == GetLastError()) )
{
break;
} //if
EnterCriticalSection(&m_members_guard);
ThisProvider = NewProvider;
NewProvider = NextProvider(m_current_provider);
if (ThisProvider == m_current_provider){
m_current_provider = NewProvider ;
} //if
LeaveCriticalSection(&m_members_guard);
} //while
InterlockedDecrement(&m_calls_in_progress);
#ifdef RASAUTODIAL
if (NewProvider == NULL &&
m_restartable &&
ReturnCode == SOCKET_ERROR)
{
PLIST_ENTRY ListEntry;
DWORD errval;
//
// Save the error in case the Autodial
// attempt fails.
//
errval = GetLastError();
//
// We only invoke Autodial once per query.
//
m_restartable = FALSE;
if (WSAttemptAutodialName(m_query_set)) {
//
// Because the providers have cached state
// about this query, we need to call
// LookupServiceEnd/LookupServiceBegin
// to reset them.
//
while (!IsListEmpty(&m_provider_list)){
ListEntry = RemoveHeadList(&m_provider_list);
ThisProvider = CONTAINING_RECORD( ListEntry,
NSPROVIDERSTATE,
m_query_linkage);
ThisProvider->LookupServiceEnd();
delete(ThisProvider);
} //while
//
// Restart the query.
//
if (LookupServiceBegin(
m_query_set,
m_control_flags|LUP_FLUSHCACHE,
m_catalog) == ERROR_SUCCESS)
{
goto again;
}
}
else
SetLastError(errval);
}
#endif // RASAUTODIAL
} //if
else{
ReturnCode = SOCKET_ERROR;
SetLastError(WSAECANCELLED);
} //else
return(ReturnCode);
}
DWORD
WSAAPI
WsNqLookupServiceNext(IN PNSQUERY NsQuery,
IN DWORD ControlFlags,
OUT PDWORD BufferLength,
OUT LPWSAQUERYSETW Results)
{
PNSQUERY_PROVIDER Provider, NextProvider;
INT ErrorCode = SOCKET_ERROR, OldErrorCode;
PLIST_ENTRY Entry;
/* Make sure we're not shutting down */
if (!NsQuery->ShuttingDown)
{
/* Acquire query lock */
WsNqLock();
/* Check if we already have an active provider */
NextProvider = NsQuery->ActiveProvider;
if (!NextProvider)
{
/* Make sure we have a current provider */
if (!NsQuery->CurrentProvider)
{
/* We don't; fail */
WsNqUnlock();
SetLastError(WSA_E_NO_MORE);
return SOCKET_ERROR;
}
/* Get the first provider on the list and start looping */
Entry = NsQuery->ProviderList.Blink;
NextProvider = CONTAINING_RECORD(Entry, NSQUERY_PROVIDER, QueryLink);
while (NextProvider)
{
/* Check if this is a new-style provider */
if (NextProvider->Provider->Service.NSPIoctl)
{
/* Remove it and re-add it on top */
RemoveEntryList(&NextProvider->QueryLink);
InsertHeadList(&NsQuery->ProviderList, &NextProvider->QueryLink);
/* Set it as the active provider and exit the loop */
NsQuery->ActiveProvider = NextProvider;
break;
}
/* Get the previous provider */
NextProvider = WsNqPreviousProvider(NsQuery, NextProvider);
}
}
/* Release the lock */
WsNqUnlock();
/* Check if we have an active provider now */
if (NextProvider)
{
/* Start loop */
do
{
/* Call its routine */
ErrorCode = WsNqProvLookupServiceNext(NextProvider,
ControlFlags,
BufferLength,
Results);
/* Check for error or shutdown */
if ((ErrorCode == ERROR_SUCCESS) ||
(GetLastError() == WSAEFAULT) || (NsQuery->ShuttingDown))
{
/* Get out */
break;
}
/* Acquire Query Lock */
WsNqLock();
/* Save the current active provider */
Provider = NsQuery->ActiveProvider;
/* Check if one exists */
if (Provider)
{
/* Get the next one */
NextProvider = WsNqNextProvider(NsQuery,
NsQuery->ActiveProvider);
/* Was the old provider our active? */
if (Provider == NsQuery->ActiveProvider)
{
/* Change our active provider to the new one */
NsQuery->ActiveProvider = NextProvider;
}
}
else
{
/* No next provider */
NextProvider = NULL;
}
/* Check if we failed and if we can try again */
if (!(NextProvider) &&
(ErrorCode == SOCKET_ERROR) &&
(NsQuery->TryAgain))
{
/* Save the error code so RAS doesn't overwrite it */
OldErrorCode = GetLastError();
/* Make sure we won't try for a 3rd time */
NsQuery->TryAgain = FALSE;
/* Call the helper to auto-dial */
if (WSAttemptAutodialName(NsQuery->QuerySet))
{
/* It suceeded, so we'll delete the current state. */
while (!IsListEmpty(&NsQuery->ProviderList))
{
/* Remove the entry and get its provider */
Entry = RemoveHeadList(&NsQuery->ProviderList);
Provider = CONTAINING_RECORD(Entry,
NSQUERY_PROVIDER,
QueryLink);
/* Reset it */
WsNqProvLookupServiceEnd(Provider);
WsNqProvDelete(Provider);
}
/* Start a new query */
if (!WsNqLookupServiceBegin(NsQuery,
NsQuery->QuerySet,
NsQuery->ControlFlags,
NsQuery->Catalog))
{
/* New query succeeded, set active provider now */
NsQuery->ActiveProvider =
WsNqNextProvider(NsQuery,
NsQuery->ActiveProvider);
}
}
else
{
/* Reset the error code */
SetLastError(OldErrorCode);
}
}
/* Release lock */
WsNqUnlock();
/* Keep looping as long as there is a provider */
} while (NextProvider);
}
}
else
{
/* We are shuting down; fail */
SetLastError(WSAECANCELLED);
}
/* Return */
return ErrorCode;
}
