/*++

   Copyright    (c)    1999    Microsoft Corporation

   Module Name :
     maincontext.cxx

   Abstract:
     Drive the state machine
 
   Author:
     Bilal Alam (balam)             10-Mar-2000

   Environment:
     Win32 - User Mode

   Project:
     ULW3.DLL
--*/

#include "precomp.hxx"
#include "rawconnection.hxx"
#include "sspiprovider.hxx"
#include "basicprovider.hxx"
#include "servervar.hxx"

//
// Global alloc cache and context list 
//

ALLOC_CACHE_HANDLER *    W3_MAIN_CONTEXT::sm_pachMainContexts = NULL;
W3_STATE *               W3_MAIN_CONTEXT::sm_pStates[ STATE_COUNT ];
SHORT                    W3_MAIN_CONTEXT::sm_rgInline[ STATE_COUNT ];
USHORT                   W3_MAIN_CONTEXT::sm_cbInlineBytes = 0;
LONG                     W3_MAIN_CONTEXT::sm_cOutstandingThreads = 0;
DWORD                    W3_MAIN_CONTEXT::sm_dwTimeout = 0;

VOID
W3_MAIN_CONTEXT::DoWork(
    DWORD                cbCompletion,
    DWORD                dwCompletionStatus,
    BOOL                 fIoCompletion
)
/*++

Routine Description:

    Drives the W3 state machine

Arguments:

    cbCompletion - Number of bytes in an async completion
    dwCompletionStatus - Error status of a completion
    fIoCompletion - TRUE if this was an IO completion,
                    FALSE if this was a new request completion

Return Value:

    None

--*/
{
    CONTEXT_STATUS         Status = CONTEXT_STATUS_CONTINUE;
    BOOL                   fLastState = FALSE;
    W3_CONTEXT *           pCurrentContext = NULL;

    if (fIoCompletion)
    {
        if (QueryLastIOPending() == LOG_WRITE_IO)
        {
            _LogContext.m_dwBytesSent += cbCompletion;
        }
        else if (QueryLastIOPending() == LOG_READ_IO)
        {
            _LogContext.m_dwBytesRecvd += cbCompletion;

            if ( _cbRemainingEntityFromUL != INFINITE )
            {
                if ( _cbRemainingEntityFromUL >= cbCompletion )
                {
                    _cbRemainingEntityFromUL -= cbCompletion;
                }
                else
                {
                    _cbRemainingEntityFromUL = 0;
                }
            }
        }
    }

    //
    // Progress thru states until we are finished or a state operation
    // is performed asynchronously
    //

    while ( !fLastState )
    {
        W3_STATE *              pState;

        //
        // Get the next function to call, and then call it
        //

        pState = sm_pStates[ _currentState ];
        DBG_ASSERT( pState != NULL );

        //
        // Manage the _nextState which indicates what the next state will be
        // if the DoWork() returns CONTEXT_STATUS_CONTINUE.  Note that this
        // state can be overriden by W3_MAIN_CONTEXT::SetFinishedResponse 
        //

        _nextState = _currentState + 1;

        //
        // If this is the last state, remember that so we can cleanup
        //

        if ( _currentState == CONTEXT_STATE_DONE )
        {
            fLastState = TRUE;
        }

        if ( !fIoCompletion )
        {
            Status = pState->DoWork( this,
                                     cbCompletion,
                                     dwCompletionStatus );
        }
        else
        {
            pCurrentContext = QueryCurrentContext();

            //
            // First try to complete handler contexts if any.  
            //

            Status = pCurrentContext->ExecuteHandlerCompletion(
                                                 cbCompletion,
                                                 dwCompletionStatus );

            if ( Status == CONTEXT_STATUS_CONTINUE )
            {   
                //
                // Excellent.  All handlers for this context have 
                // completed.  Now we finally complete the original
                // state which originally started the async ball rolling
                //

                Status = pState->OnCompletion( this,
                                               cbCompletion,
                                               dwCompletionStatus );
            }

            //
            // Reset fIoCompletion so we can continue the state machine
            // after the completion function is done 
            //
            fIoCompletion = FALSE;

        }
        
        //
        // An async operation was posted, bail immediately
        //

        if ( Status == CONTEXT_STATUS_PENDING )
        {
            return;
        }

        DBG_ASSERT( Status == CONTEXT_STATUS_CONTINUE );

        _currentState = _nextState;
    }

    //
    // If we get here, we must have executed the last state, so cleanup the
    // MAIN_CONTEXT
    //

    DBG_ASSERT( fLastState );
   
    //
    // If we have a raw connection, detach ourselves from it now
    //
    
    if ( _pRawConnection != NULL )
    {
        _pRawConnection->SetMainContext( NULL );
    }
    
    DereferenceMainContext();
}

VOID
W3_MAIN_CONTEXT::BackupStateMachine(
    VOID
)
/*++

Routine Description:

    Backup in state machine to the URL_INFO state.  This should be used only
    by AUTH_COMPLETE filters

Arguments:

    None
    
Return Value:

    None

--*/
{
    URL_CONTEXT *           pUrlContext;
    
    DBG_ASSERT( IsNotificationNeeded( SF_NOTIFY_AUTH_COMPLETE ) );

    //
    // Clear the URL context
    //

    pUrlContext = QueryUrlContext();
    DBG_ASSERT( pUrlContext != NULL );
    
    SetUrlContext( NULL );
    
    delete pUrlContext;
    
    //
    // Reset our access check state.  
    //
    
    ResetAccessCheck();
    
    //
    // Back that state up
    //
    
    _nextState = CONTEXT_STATE_URLINFO;   
}

// static
HRESULT
W3_MAIN_CONTEXT::SetupStateMachine(
    VOID
)
/*++

Routine Description:

    Setup state machine

Arguments:

    None
    
Return Value:

    HRESULT

--*/
{
    HRESULT                     hr = NO_ERROR;
    W3_STATE *                  pState = NULL;
    USHORT                      cbContextSize = 0;
    DWORD                       cState = CONTEXT_STATE_START;
    
    //
    // First create all the states
    //
    
    //
    // Start State
    //
     
    pState = (W3_STATE*) new W3_STATE_START();
    if ( pState == NULL )
    {
        hr = HRESULT_FROM_WIN32( ERROR_NOT_ENOUGH_MEMORY );
        goto Failure;
    }
    else if ( FAILED( hr = pState->QueryResult() ) )
    {
        goto Failure;
    }
    
    sm_pStates[ cState ] = pState;
    cbContextSize += pState->QueryContextSize();
    //
    // provide space for 8 bit alignment
    //
    cbContextSize = (cbContextSize + 7) & ~7;
    cState++;

    //
    // URLINFO State
    //
     
    pState = (W3_STATE*) new W3_STATE_URLINFO();
    if ( pState == NULL )
    {
        hr = HRESULT_FROM_WIN32( ERROR_NOT_ENOUGH_MEMORY );
        goto Failure;
    }
    else if ( FAILED( hr = pState->QueryResult() ) )
    {
        goto Failure;
    }
    
    sm_pStates[ cState ] = pState;
    cbContextSize += pState->QueryContextSize();
    //
    // provide space for 8 bit alignment
    //
    cbContextSize = (cbContextSize + 7) & ~7;
    cState++;

    //
    // Authentication State
    //
     
    pState = (W3_STATE*) new W3_STATE_AUTHENTICATION();
    if ( pState == NULL )
    {
        hr = HRESULT_FROM_WIN32( ERROR_NOT_ENOUGH_MEMORY );
        goto Failure;
    }
    else if ( FAILED( hr = pState->QueryResult() ) )
    {
        goto Failure;
    }
    
    sm_pStates[ cState ] = pState;
    cbContextSize += pState->QueryContextSize();
    //
    // provide space for 8 bit alignment
    //
    cbContextSize = (cbContextSize + 7) & ~7;
    cState++;

    //
    // Authorization State
    //
     
    pState = (W3_STATE*) new W3_STATE_AUTHORIZATION();
    if ( pState == NULL )
    {
        hr = HRESULT_FROM_WIN32( ERROR_NOT_ENOUGH_MEMORY );
        goto Failure;
    }
    else if ( FAILED( hr = pState->QueryResult() ) )
    {
        goto Failure;
    }
    
    sm_pStates[ cState ] = pState;
    cbContextSize += pState->QueryContextSize();
    //
    // provide space for 8 bit alignment
    //
    cbContextSize = (cbContextSize + 7) & ~7;
    cState++;

    //
    // Handle Request State
    //
     
    pState = (W3_STATE*) new W3_STATE_HANDLE_REQUEST();
    if ( pState == NULL )
    {
        hr = HRESULT_FROM_WIN32( ERROR_NOT_ENOUGH_MEMORY );
        goto Failure;
    }
    else if ( FAILED( hr = pState->QueryResult() ) )
    {
        goto Failure;
    }
    
    sm_pStates[ cState ] = pState;
    cbContextSize += pState->QueryContextSize();
    //
    // provide space for 8 bit alignment
    //
    cbContextSize = (cbContextSize + 7) & ~7;
    cState++;

    //
    // Response State
    //
     
    pState = (W3_STATE*) new W3_STATE_RESPONSE();
    if ( pState == NULL )
    {
        hr = HRESULT_FROM_WIN32( ERROR_NOT_ENOUGH_MEMORY );
        goto Failure;
    }
    else if ( FAILED( hr = pState->QueryResult() ) )
    {
        goto Failure;
    }
    
    sm_pStates[ cState ] = pState;
    cbContextSize += pState->QueryContextSize();
    //
    // provide space for 8 bit alignment
    //
    cbContextSize = (cbContextSize + 7) & ~7;
    cState++;

    //
    // Log State
    //
     
    pState = (W3_STATE*) new W3_STATE_LOG();
    if ( pState == NULL )
    {
        hr = HRESULT_FROM_WIN32( ERROR_NOT_ENOUGH_MEMORY );
        goto Failure;
    }
    else if ( FAILED( hr = pState->QueryResult() ) )
    {
        goto Failure;
    }
    
    sm_pStates[ cState ] = pState;
    cbContextSize += pState->QueryContextSize();
    //
    // provide space for 8 bit alignment
    //
    cbContextSize = (cbContextSize + 7) & ~7;
    cState++;

    //
    // Done State
    //
     
    pState = (W3_STATE*) new W3_STATE_DONE();
    if ( pState == NULL )
    {
        hr = HRESULT_FROM_WIN32( ERROR_NOT_ENOUGH_MEMORY );
        goto Failure;
    }
    else if ( FAILED( hr = pState->QueryResult() ) )
    {
        goto Failure;
    }
    
    sm_pStates[ cState ] = pState;
    cbContextSize += pState->QueryContextSize();
    //
    // provide space for 8 bit alignment
    //
    cbContextSize = (cbContextSize + 7) & ~7;
    cState++;

    //
    // Keep track of total number of state bytes needed so that we can
    // initialize allocation cache properly
    //

    // throw in 8 more bytes, alignment may cause us to need it
    sm_cbInlineBytes = cbContextSize + 8;
    
    return NO_ERROR;

Failure:

    for ( int i = 0; i < STATE_COUNT; i++ )
    {
        if ( sm_pStates[ i ] != NULL )
        {
            delete sm_pStates[ i ];
            sm_pStates[ i ] = NULL;
        }
    }
    
    return hr;
}

// static
VOID
W3_MAIN_CONTEXT::CleanupStateMachine(
    VOID
)
/*++

Routine Description:

    Cleanup state machine

Arguments:

    None

Return Value:

    None

--*/
{
    for ( int i = CONTEXT_STATE_START;
          i < STATE_COUNT;
          i++ )
    {
        if ( sm_pStates[ i ] != NULL )
        {
            delete sm_pStates[ i ];
            sm_pStates[ i ] = NULL;
        }
    }
}

BOOL
W3_MAIN_CONTEXT::SetupContext(
    HTTP_REQUEST *          pUlHttpRequest,
    ULATQ_CONTEXT           ulatqContext
)
/*++

Routine Description:

    Sets up a MAIN_CONTEXT before executing the state machine for a new
    incoming request.  

Arguments:

    pUlHttpRequest - the HTTP_REQUEST from UL
    ulatqContext - used to send/receive data thru ULATQ

Return Value:

    TRUE if successful, else FALSE

--*/
{   
    memset( _rgStateContexts, 0, sizeof( _rgStateContexts ) );

    //
    // Should we generate a content-length header
    //
    
    if ( pUlHttpRequest->Verb == HttpVerbHEAD )
    {
        _fGenerateContentLength = TRUE;
    }

    //
    // Associate HTTP_REQUEST with W3_REQUEST wrapper
    //

    _request.SetHttpRequest( pUlHttpRequest );

    //
    // Associate context for async IO (if any)
    //

    _ulatqContext = ulatqContext;  

    UlAtqSetContextProperty( _ulatqContext,
                             ULATQ_PROPERTY_COMPLETION_CONTEXT,
                             this );

    //
    // Setup the state machine
    //    

    _currentState = CONTEXT_STATE_START;
    _nextState = CONTEXT_STATE_START;

    //
    // Setup current context to receive IO completions.  Naturally on 
    // startup, this context will be 'this'.  But it can change depending
    // on whether child executes are called
    //

    _pCurrentContext = this;

    return TRUE;
}

W3_CONNECTION_STATE *
W3_MAIN_CONTEXT::QueryConnectionState(
    VOID
)
/*++

Routine Description:

    Get any context associated with this connection and this state.

Arguments:

    None

Return Value:

    A W3_CONNECTION_STATE * or NULL if there is no state

--*/
{
    //
    // Since we are just looking for any existing connection state, make 
    // sure we don't create a connection object if none is already associated
    // (creating a connection object is expensive)
    //
    
    W3_CONNECTION *     pConn = QueryConnection( FALSE );

    return pConn ? pConn->QueryConnectionState( _currentState ) : NULL;
}

VOID
W3_MAIN_CONTEXT::SetConnectionState(
    W3_CONNECTION_STATE *       pConnectionState
)
/*++

Routine Description:

    Set any context to be associated with the connection and current state

Arguments:

    pConnectionState - Context to associate

Return Value:

    None

--*/
{ 
    if ( QueryConnection() )
    {
        QueryConnection()->SetConnectionState( _currentState,
                                               pConnectionState );
    }
}

W3_MAIN_CONTEXT::W3_MAIN_CONTEXT(
    HTTP_REQUEST *          pUlHttpRequest,
    ULATQ_CONTEXT           ulAtqContext
) 
    : W3_CONTEXT            ( 0 ),
      _pSite                ( NULL ),
      _pFilterContext       ( NULL ),
      _fDisconnect          ( FALSE ),
      _fNeedFinalDone       ( FALSE ),
      _fAssociationChecked  ( FALSE ),
      _pConnection          ( NULL ),
      _pUrlContext          ( NULL ),
      _pUserContext         ( NULL ),
      _fProviderHandled     ( FALSE ),
      _cbInlineOffset       ( 0 ),
      _fDoneWithCompression ( FALSE ),
      _pCompressionContext  ( NULL ),
      _fIsUlCacheable       ( TRUE ),
      _pCertificateContext  ( NULL ),
      _cbRemainingEntityFromUL ( 0 ),
      _fGenerateContentLength( FALSE ),
      _pRawConnection       ( NULL ),
      _cRefs                ( 1 ),
      _hTimer               (NULL)
{
    _LogContext.m_msStartTickCount = GetTickCount();

    SetupContext( pUlHttpRequest, ulAtqContext );

    _hTimer = NULL;

    if (sm_dwTimeout)
    {
        BOOL fRet;
        fRet = CreateTimerQueueTimer(&_hTimer,
                                     NULL,
                                     W3_MAIN_CONTEXT::TimerCallback,
                                     this,
                                     sm_dwTimeout,
                                     0,
                                     WT_EXECUTEONLYONCE
                                     );
        DBG_ASSERT(fRet);
    }

}

W3_MAIN_CONTEXT::~W3_MAIN_CONTEXT()
/*++

Routine Description:

    Main context destructor

Arguments:

    None

Return Value:

    None

--*/
{
    //
    // Cleanup context state
    //
    
    for ( DWORD i = 0; i < STATE_COUNT; i++ )
    {
        if ( _rgStateContexts[ i ] != NULL ) 
        {
            ((W3_MAIN_CONTEXT_STATE*) _rgStateContexts[ i ])->Cleanup( this );
            _rgStateContexts[ i ] = NULL;
        }
    }
    
    //
    // Let our filter context go
    //
    
    if ( _pFilterContext != NULL )
    {
        _pFilterContext->SetMainContext( NULL );
        _pFilterContext->DereferenceFilterContext();
        _pFilterContext = NULL;
    }
    
    //
    // Let go of reference to associated connection
    //
   
    if ( _pConnection != NULL )
    {
        _pConnection->DereferenceConnection();
        _pConnection = NULL;
    }
    
    //
    // Cleanup URL-Context
    //
    
    if ( _pUrlContext != NULL )
    {
        delete _pUrlContext;
        _pUrlContext = NULL;
    }
    
    //
    // Release our user context
    //
    
    if ( _pUserContext != NULL )
    {
        // perf ctr
        if (_pUserContext->QueryAuthType() == MD_AUTH_ANONYMOUS)
        {
            _pSite->DecAnonUsers();
        }
        else
        {
            _pSite->DecNonAnonUsers();
        }

        _pUserContext->DereferenceUserContext();
        _pUserContext = NULL;
    }

    //
    // Release the compression context
    //
    if ( _pCompressionContext != NULL )
    {
        delete _pCompressionContext;
        _pCompressionContext = NULL;
    }
    
    //
    // Cleanup RDNS crud
    //
    
    _IpAddressCheck.UnbindAddr();

    //
    // Cleanup client certificate context
    //
    
    if ( _pCertificateContext != NULL )
    {
        delete _pCertificateContext;
        _pCertificateContext = NULL;
    }
    
    //
    // Release the raw connection now
    //
    
    if ( _pRawConnection != NULL )
    {
        _pRawConnection->DereferenceRawConnection();
        _pRawConnection = NULL;
    }

    //
    // Allow ULATQ to cleanup itself up and to read the next request
    //

    UlAtqFreeContext( _ulatqContext );
    _ulatqContext = NULL;

    //
    // Finally release the site
    //
    if ( _pSite )
    {
        _pSite->Release();
        _pSite = NULL;
    }

    if (_hTimer)
    {
        BOOL fRet;
        fRet = DeleteTimerQueueTimer(NULL,
                                    _hTimer,
                                    INVALID_HANDLE_VALUE);
        DBG_ASSERT(fRet);
        _hTimer = NULL;
    }

}

// static
HRESULT
W3_MAIN_CONTEXT::Initialize(
    VOID
)
/*++

Routine Description:

    Global initialization routine for W3_MAIN_CONTEXTs

Arguments:

    None
    
Return Value:

    HRESULT

--*/
{
    ALLOC_CACHE_CONFIGURATION       acConfig;
    HRESULT                         hr = NO_ERROR;

    //
    // Setup global state machine.  We do this BEFORE we setup the 
    // allocation cache because the state machine setup will tell how much
    // inline buffer space is needed for state
    //
    
    hr = SetupStateMachine();
    if ( FAILED( hr ) )
    {
        return hr;
    } 
    
    //
    // Setup allocation lookaside
    //
    
    acConfig.nConcurrency = 1;
    acConfig.nThreshold = 100;
    acConfig.cbSize = sizeof( W3_MAIN_CONTEXT ) + sm_cbInlineBytes;

    DBG_ASSERT( sm_pachMainContexts == NULL );
    
    sm_pachMainContexts = new ALLOC_CACHE_HANDLER( "W3_MAIN_CONTEXT",  
                                                   &acConfig );

    if ( sm_pachMainContexts == NULL )
    {
        CleanupStateMachine();
        return HRESULT_FROM_WIN32( ERROR_NOT_ENOUGH_MEMORY );
    }
        
    sm_dwTimeout = ReadRegDword(HKEY_LOCAL_MACHINE, 
                                REGISTRY_KEY_INETINFO_PARAMETERS_W, 
                                L"RequestTimeoutBreak", 
                                0);

    return NO_ERROR;
}

// static
VOID
W3_MAIN_CONTEXT::WaitForThreadDrain(
    VOID
)
/*++

Routine Description:

    Wait for all threads doing W3CORE stuff to drain away

Arguments:

    None
    
Return Value:

    None

--*/
{
    while ( sm_cOutstandingThreads != 0 )
    {
        Sleep( 200 );
    }
}

// static
VOID
W3_MAIN_CONTEXT::Terminate(
    VOID
)
/*++

Routine Description:

    Terminate MAIN_CONTEXT globals

Arguments:

    None
    
Return Value:

    None

--*/
{
    CleanupStateMachine();

    if ( sm_pachMainContexts != NULL )
    {
        delete sm_pachMainContexts;
        sm_pachMainContexts = NULL;
    }
}

W3_USER_CONTEXT *
W3_MAIN_CONTEXT::QueryConnectionUserContext(
    VOID
)
/*++

Routine Description:

    Get any user context associated with this connection

Arguments:

    None

Return Value:

    Pointer to W3_USER_CONTEXT (or NULL if no used associated)

--*/
{
    W3_CONNECTION *         pConnection = NULL;
    
    pConnection = QueryConnection( FALSE );
    if ( pConnection != NULL )
    {
        return pConnection->QueryUserContext();
    }
    else
    {
        return NULL;
    }
}
    
VOID
W3_MAIN_CONTEXT::SetConnectionUserContext(
    W3_USER_CONTEXT *           pUserContext
)
/*++

Routine Description:

    Associate user context with connection

Arguments:

    pUserContext - User context to associate

Return Value:

    None

--*/
{
    W3_CONNECTION *         pConnection = NULL;
    
    pConnection = QueryConnection( TRUE );
    if ( pConnection != NULL )
    {
        pConnection->SetUserContext( pUserContext );
    }
    else
    {
        DBG_ASSERT( FALSE );
    }
}

HRESULT
W3_MAIN_CONTEXT::ReceiveEntityBody(
    BOOL            fAsync,
    VOID *          pBuffer,
    DWORD           cbBuffer,
    DWORD *         pBytesReceived
    )
/*++

Routine Description:

    Receives entity data from the client

Arguments:

    fAsync - TRUE if this is an async request
    pBuffer - The buffer to store the data
    cbBuffer - The size of the buffer
    pBytesReceived - Upon return, the amount of data copied
                     into the buffer

Return Value:

    HRESULT

--*/
{
    HRESULT hr = UlAtqReceiveEntityBody( QueryUlatqContext(),
                                         fAsync,
                                         0,
                                         pBuffer,
                                         cbBuffer,
                                         pBytesReceived );

    //
    // Keep track of how much we're reading
    //

    if (!fAsync &&
        SUCCEEDED(hr))
    {
        if ( _cbRemainingEntityFromUL != INFINITE )
        {
            if ( _cbRemainingEntityFromUL >= *pBytesReceived )
            {
                _cbRemainingEntityFromUL -= *pBytesReceived;
            }
            else
            {
                _cbRemainingEntityFromUL = 0;
            }
        }
    }

    return hr;
}

W3_CONNECTION *
W3_MAIN_CONTEXT::QueryConnection(
    BOOL                fCreateIfNotFound
)
/*++

Routine Description:

    Get the W3_CONNECTION object associated with this request

Arguments:

    fCreateIfNotFound - If not found in hash table, create it

Return Value:

    Pointer to W3_CONNECTION.

--*/
{
    HRESULT             hr;

    if ( _pConnection == NULL )
    {
        //
        // Get the connection associated with this request
        //
        
        if ( !fCreateIfNotFound && _fAssociationChecked )
        {
            //
            // If we have already looked for the connection, and we're not
            // required to create one, then we can fast path
            //
            
            hr = HRESULT_FROM_WIN32( ERROR_FILE_NOT_FOUND );
        }
        else
        {
            hr = W3_CONNECTION::RetrieveConnection( _request.QueryConnectionId(),
                                                    fCreateIfNotFound,
                                                    &_pConnection );
        }
        
        if ( FAILED( hr ) )
        {
            if ( fCreateIfNotFound )
            {
                DBGPRINTF(( DBG_CONTEXT,
                            "Error retrieving connection.  hr = %x\n",
                            hr ));
            }
            else
            {
                //
                // Not really an error.  We were just querying the hash table
                // for an associated connection (but not creating one)
                //
            }
        }
        else
        {
            DBG_ASSERT( _pConnection != NULL );
        }
        
        //
        // Don't try to repeat connection lookup again
        //
        
        _fAssociationChecked = TRUE;
    }
    
    return _pConnection;
}

VOID *
W3_MAIN_CONTEXT::ContextAlloc(
    UINT                cbSize
)
/*++

Routine Description:

    Allocate context space from inline buffer in MAIN_CONTEXT.  This 
    complicated mechanism allows for states to allocate small state 
    without going to the heap.

Arguments:

    cbSize - Size to allocate
    
Return Value:

    Pointer to buffer

--*/
{
    BYTE *pOrigBuffer = (PBYTE) QueryInlineBuffer() + _cbInlineOffset;

    //
    // Make space for 8 byte alignment
    //
    VOID *pBuffer = (VOID *)(((DWORD_PTR)pOrigBuffer + 7) & ~7);
    _cbInlineOffset += DIFF((PBYTE)pBuffer - pOrigBuffer);
    
    if ( _cbInlineOffset + cbSize > sm_cbInlineBytes )
    {
        DBG_ASSERT( FALSE );
        return NULL;
    }
    
    _cbInlineOffset += cbSize;
    
    return pBuffer; 
}

BOOL
W3_MAIN_CONTEXT::NotifyFilters(
    DWORD                   dwNotification,
    PVOID                   pvFilterInfo,
    BOOL *                  pfFinished
)
/*++

Routine Description:

    Notify all applicable filters for a given notification.  This is a 
    wrapper of the W3_FILTER_CONTEXT call to actually do the work.  The 
    notifications made in this routine are those which would occur during
    the worker process state machine.  (excludes end_of_net_session and
    raw data notifications)

Arguments:

    dwNotification - Notification in question
    pvFilterInfo - Points to any info object passed to filter
    pfFinished - Set to TRUE if the filter decided to complete work
    
Return Value:

    BOOL

--*/
{
    BOOL                fRet = FALSE;
    BOOL                fSynchronized = FALSE;

    DBG_ASSERT( _pFilterContext != NULL );
    
    _pFilterContext->FilterLock();

    switch( dwNotification )
    {
    case SF_NOTIFY_PREPROC_HEADERS:
        fRet = _pFilterContext->NotifyPreProcHeaderFilters( pfFinished );
        break;
        
    case SF_NOTIFY_URL_MAP:
        fRet = _pFilterContext->NotifyUrlMap( (HTTP_FILTER_URL_MAP*) pvFilterInfo,
                                              pfFinished );
        break;

    case SF_NOTIFY_AUTHENTICATION:
        fRet = _pFilterContext->NotifyAuthentication( (HTTP_FILTER_AUTHENT*) pvFilterInfo,
                                                      pfFinished );
        break;
        
    case SF_NOTIFY_AUTH_COMPLETE:
        fRet = _pFilterContext->NotifyAuthComplete( 
                    ( HTTP_FILTER_AUTH_COMPLETE_INFO * )pvFilterInfo,
                    pfFinished );
        break;

    case SF_NOTIFY_SEND_RESPONSE:
        fRet = _pFilterContext->NotifySendResponseFilters( 
                            (HTTP_FILTER_SEND_RESPONSE*) pvFilterInfo,
                            pfFinished );
        break;

    case SF_NOTIFY_END_OF_REQUEST:
        fRet = _pFilterContext->NotifyEndOfRequest();
        break;

    case SF_NOTIFY_LOG:
        fRet = _pFilterContext->NotifyLogFilters((HTTP_FILTER_LOG *)pvFilterInfo);
        break;
        
    case SF_NOTIFY_SEND_RAW_DATA:
        fRet = _pFilterContext->NotifySendRawFilters(
                            (HTTP_FILTER_RAW_DATA*) pvFilterInfo,
                            pfFinished );
        break;        
        
    default:
        DBG_ASSERT( FALSE );
        fRet = FALSE;
    }

    _pFilterContext->FilterUnlock();
    
    return fRet;
}    

W3_FILTER_CONTEXT *
W3_MAIN_CONTEXT::QueryFilterContext(
    BOOL                    fCreateIfNotFound
)
/*++

Routine Description:

    Get a filter context to associate with the MAIN_CONTEXT and to also (
    AAAAAAAARRRRRRRGGGGGGGHHHHHH) associate with the connection on the
    W3_CONTXT

Arguments:

    fCreateIfNotFound - Should we create a context if it doesn't already exist
    
Return Value:

    Pointer to a new W3_FILTER_CONTEXT

--*/
{
    BOOL                            fSecure;
    
    if ( _pFilterContext == NULL &&
         fCreateIfNotFound )
    {
        fSecure = QueryRequest()->IsSecureRequest();

        DBG_ASSERT( _pSite != NULL );
       
        _pFilterContext = new W3_FILTER_CONTEXT( fSecure,
                                                 _pSite->QueryFilterList() );
        if ( _pFilterContext != NULL )
        {
            _pFilterContext->SetMainContext( this );
        }
        else
        {
            DBG_ASSERT( FALSE );
        }
    }
    return _pFilterContext;
}

BOOL
W3_MAIN_CONTEXT::IsNotificationNeeded(
    DWORD                   dwNotification
)
/*++
Routine Description:

    Is a specific filter notification applicable for this request

Arguments:

    dwNotification - Notification in question
    
Return Value:

    BOOL

--*/
{
    BOOL                fNeeded = FALSE;
    FILTER_LIST *       pFilterList = NULL;
    W3_FILTER_CONTEXT * pW3Context = NULL;

    if ( _pSite != NULL )
    {
        //
        // To avoid creating connection contexts, do the simple fast check
        // to determine whether the given contexts site supports the 
        // notification.  If it does, then we have to do the more robust
        // check to determine whether this specific request requires the 
        // notification (there is a difference because a filter can 
        // disable itself on the fly for any given request)
        //
        
        pFilterList = _pSite->QueryFilterList();
        DBG_ASSERT( pFilterList != NULL );

        if ( pFilterList->IsNotificationNeeded( dwNotification, 
                                                QueryRequest()->IsSecureRequest() ) )
        {
            pW3Context = QueryFilterContext();
            if ( pW3Context != NULL )
            {
                fNeeded = pW3Context->IsNotificationNeeded( dwNotification );
            }
        }
    }
    
    return fNeeded;
}

BOOL 
W3_MAIN_CONTEXT::QueryExpiry( 
    LARGE_INTEGER *           pExpiry 
)
/*++

Routine Description:

    Queries the expiration date/time for logon user

Arguments:

    pExpiry - ptr to buffer to update with expiration date

Return Value:

    TRUE if successful, FALSE if not available

--*/
{
    SECURITY_STATUS                ss;
    SecPkgContext_PasswordExpiry   speExpiry;
    SSPI_SECURITY_CONTEXT        * pSecurityContext;
    W3_USER_CONTEXT              * pW3UserContext;
    LARGE_INTEGER                * pUserAcctExpiry = NULL;

    
    pUserAcctExpiry = _pUserContext->QueryExpiry();

    if ( pUserAcctExpiry == NULL )
    {
        ((LARGE_INTEGER*)pExpiry)->HighPart = 0x7fffffff;
        ((LARGE_INTEGER*)pExpiry)->LowPart = 0xffffffff;
        return FALSE;
    }
    else
    {
        memcpy( pExpiry, 
                pUserAcctExpiry, 
                sizeof( LARGE_INTEGER ) );
    }
    return TRUE;

}

HRESULT
W3_MAIN_CONTEXT::ExecuteExpiredUrl(
    STRU & strExpUrl
)
/*++

Routine Description:

    Do child execution on the server configed expire url

Arguments:

    strExpUrl - The configed expire url to be executed

Return Value:

    HRESULT

--*/
{
    HRESULT             hr;
    AUTH_PROVIDER *     pAnonymousProvider = NULL;
    STRA                strNewHeader;
    STRA                strNewValue;


    pAnonymousProvider = W3_STATE_AUTHENTICATION::QueryAnonymousProvider();
    DBG_ASSERT( pAnonymousProvider != NULL );
    
    hr = pAnonymousProvider->DoAuthenticate( this );
    if( FAILED( hr ) )
    {
        return hr;
    }

    //
    // Execute a child request
    //
    QueryResponse()->Clear();
    QueryResponse()->SetStatus( HttpStatusOk );
    
    //
    // Reset the new url to be executed
    //
    hr = QueryRequest()->SetUrl( strExpUrl );
    if( FAILED( hr ) )
    {
        return hr;
    } 

    //
    // Add CFG_ENC_CAPS header and set its value to 1 to indicate 
    // the site support SSL, to 0 if not.
    //
    strNewHeader.Copy( "CFG-ENC-CAPS" );
    
    if( QuerySite()->QuerySSLSupported() )
    {
        strNewValue.Copy( "1" );
    }
    else
    {
        strNewValue.Copy( "0" );
    }
       
    hr = QueryRequest()->SetHeader( strNewHeader,
                                    strNewValue,
                                    TRUE );
    if( FAILED( hr ) )
    {
        return hr;
    }

    //
    // Set the auth access check flag to FALSE so the 
    // child execution won't do auth access check
    //

    SetAuthAccessCheckRequired( FALSE );

    //
    // Set finished response for parent
    //
    SetFinishedResponse();


    //
    // Execute child request
    //
    hr = ExecuteChildRequest( QueryRequest(),
                              FALSE,
                              W3_FLAG_ASYNC );

    return hr;
}

HRESULT
W3_MAIN_CONTEXT::PasswdExpireNotify(
    VOID
)
/*++

Routine Description:

    Check if the user password has been expired

Arguments:

    None

Return Value:

    HRESULT

--*/
{
    HRESULT             hr = S_FALSE;
    LARGE_INTEGER       cExpire;
    FILETIME            ftNow;
    DWORD               dwExpireInDay;
    DWORD               dwTotalRequired;
    STACK_STRU        ( strExpUrl,  MAX_PATH );
    STACK_STRU        ( strFullUrl, MAX_PATH );
    STRU              * pstrAdvNotPwdExpUrl;
    BYTE                byTokenInfo[ SID_DEFAULT_SIZE + sizeof( TOKEN_USER ) ];
    PSID                pSid;

    if ( QueryExpiry( &cExpire ) )
    {
        if ( cExpire.HighPart == 0x7fffffff )
        {
            //
            // Password never expire
            //

            return hr;
        }
        else
        {
            GetSystemTimeAsFileTime( &ftNow );

            if ( *( __int64 * )&cExpire > *( __int64 * )&ftNow )
            {
                dwExpireInDay = ( DWORD )( ( * ( __int64 * )&cExpire
                                - *( __int64 * )&ftNow )
                                / ( ( __int64 )10000000 * 86400 ) );
                                
                if ( QuerySite()->QueryAdvNotPwdExpInDays() && 
                     dwExpireInDay <= QuerySite()->QueryAdvNotPwdExpInDays() )
                {
                    pstrAdvNotPwdExpUrl = QuerySite()->QueryAdvNotPwdExpUrl(); 
                    if( pstrAdvNotPwdExpUrl == NULL )
                    {
                        //
                        // Advanced password expire notification disabled
                        //
                        return hr;
                    }

                    //
                    // Check this SID has not already been notified
                    // of pwd expiration
                    //

                    if ( GetTokenInformation( 
                                 QueryUserContext()->QueryPrimaryToken(),
                                 TokenUser,
                                 ( LPVOID )byTokenInfo,
                                 sizeof( byTokenInfo ),
                                 &dwTotalRequired ) )
                    {
                        pSid = ( ( TOKEN_USER * )byTokenInfo )->User.Sid;

                        if( !PenCheckPresentAndResetTtl( 
                                     pSid,
                                     QuerySite()->QueryAdvCacheTTL() ) )
                        {
                            PenAddToCache( 
                                     pSid,
                                     QuerySite()->QueryAdvCacheTTL() );

                            //
                            // flush cache when connection close
                            // so that account change will not be masked
                            // by cached information
                            //

                            if( QueryUserContext()->QueryAuthType() == 
                                MD_AUTH_BASIC )
                            {
                                g_pW3Server->QueryTokenCache()->FlushCacheEntry( 
                                  ( ( BASIC_USER_CONTEXT * )QueryUserContext() )
                                   ->QueryCachedToken()->QueryCacheKey() );
                            }

                            hr = strExpUrl.Copy( pstrAdvNotPwdExpUrl->
                                                     QueryStr() );
                            if( FAILED( hr ) )
                            {
                                return hr;
                            }

                            if ( strExpUrl.QueryStr()[0] == NULL )
                            {
                                return E_FAIL;
                            }
                            
                            //
                            // Add the arg to be passed to the 
                            // password-change URL - argument is the
                            // URL the user is pointed to after all 
                            // the password-change processing is done 
                            //

                            hr = strExpUrl.Append( L"?" );
                            if( FAILED( hr ) )
                            {
                                return hr;
                            }

                            hr = QueryRequest()->GetOriginalFullUrl( 
                                                       &strFullUrl );
                            if( FAILED( hr ) )
                            {
                                return hr;
                            }

                            hr = strExpUrl.Append( strFullUrl );
                            if( FAILED( hr ) )
                            {
                                return hr;
                            }
                                
                            return ExecuteExpiredUrl( strExpUrl );
                        }
                    }
                }
            }
            else
            {
                //
                // flush cache when connection close
                // since the password has expired
                //

                if( QueryUserContext()->QueryAuthType() == MD_AUTH_BASIC )
                {
                    g_pW3Server->QueryTokenCache()->FlushCacheEntry( 
                      ( ( BASIC_USER_CONTEXT * )QueryUserContext() )
                       ->QueryCachedToken()->QueryCacheKey() );
                }

                return PasswdChangeExecute();
            }
        }
    }

    return hr;
}

HRESULT
W3_MAIN_CONTEXT::PasswdChangeExecute(
    VOID    
)
/*++

Routine Description:

    This method handles password expiration notification

Arguments:

    None

Return Value:

    HRESULT

--*/
{
    HRESULT             hr = S_FALSE;
    STACK_STRU        ( strExpUrl,  MAX_PATH );
    STACK_STRU        ( strFullUrl, MAX_PATH );
    STACK_STRU        ( strUrl,     MAX_PATH );
    STRU              * pstrAuthExpiredUrl;

    pstrAuthExpiredUrl = QuerySite()->QueryAuthExpiredUrl();
    
    if( pstrAuthExpiredUrl == NULL )
    {
        //
        // S_FALSE means password change disabled
        //

        return hr;

    } 

    hr = strExpUrl.Copy( pstrAuthExpiredUrl->QueryStr() );
    if( FAILED( hr ) )
    {
        return hr;
    }

    if ( strExpUrl.QueryStr()[0] == NULL )
    {
        return E_FAIL;
    }

    hr = QueryRequest()->GetUrl( &strUrl );
    if( FAILED( hr ) )
    {
        return hr;
    }

    //
    // Add the arg to be passed to the password-change URL - argument 
    // is the URL the user is pointed to after all the password-change 
    // processing is done 
    //
    hr = strExpUrl.Append( L"?" );
    if ( FAILED( hr ) )
    {
        return hr;
    }

    hr = QueryRequest()->GetOriginalFullUrl( &strFullUrl );
    if( FAILED( hr ) )
    {
        return hr;
    }

    hr = strExpUrl.Append( strFullUrl );
    if( FAILED( hr ) )
    {
        return hr;
    }
    
    return ExecuteExpiredUrl( strExpUrl );
}

HRESULT
W3_MAIN_CONTEXT::GetRemoteDNSName(
    STRA *              pstrDNSName
)
/*++

Routine Description:

    Get remote client's DNS name if it is resolved

Arguments:

    pstrDNSName - Filled with DNS name on success

Return Value:

    HRESULT

--*/
{
    DBG_ASSERT( pstrDNSName != NULL );
    
    if ( _IpAddressCheck.IsDnsResolved() )
    {
        return pstrDNSName->Copy( _IpAddressCheck.QueryResolvedDnsName() );
    }
    else
    {
        return HRESULT_FROM_WIN32( ERROR_NOT_SUPPORTED );
    }
}

CONTEXT_STATUS
W3_STATE_START::DoWork(
    W3_MAIN_CONTEXT *       pMainContext,
    DWORD                   cbCompletion,
    DWORD                   dwCompletionStatus
)
/*++

Routine Description:

    Initial start state handling

Arguments:

    pMainContext - W3_MAIN_CONTEXT representing an execution of the state machine
    cbCompletion - Number of bytes on completion
    dwCompletionStatus - Win32 Error on completion (if any)
    
Return Value:

    CONTEXT_STATUS_CONTINUE - if we should continue in state machine
    else stop executing the machine and free up the current thread

--*/
{
    W3_REQUEST *                    pRequest;
    DWORD                           dwSiteId;
    HRESULT                         hr;
    W3_SITE *                       pSite;
    BOOL                            fFinished = FALSE;
    BOOL                            fNeedRawRead = FALSE;
    RAW_CONNECTION *                pRawConnection = NULL;
    W3_FILTER_CONTEXT *             pFilterContext = NULL;
    
    //
    // Get the request out of the context and the SiteId out of the request
    //
    
    pRequest = pMainContext->QueryRequest();
    DBG_ASSERT( pRequest != NULL );
    
    dwSiteId = pRequest->QuerySiteId();

    //
    // Check if this site already exists
    //
    
    pSite = g_pW3Server->FindSite( dwSiteId );

    //
    // Now we need to do some locking while adding this site
    //

    if ( pSite == NULL )
    {
        g_pW3Server->WriteLockSiteList();

        //
        // try again, avoid race condition
        //
        
        pSite = g_pW3Server->FindSite( dwSiteId );
        if ( pSite == NULL )
        {
            //
            // Need to create a new site!
            //
            
            pSite = new W3_SITE( dwSiteId );
            if ( pSite == NULL )
            {
                hr = HRESULT_FROM_WIN32( ERROR_NOT_ENOUGH_MEMORY );
            }
            else
            {
                hr = pSite->Initialize();
            }
            
            if ( FAILED( hr ) )
            {
                if ( pSite != NULL )
                {
                    pSite->Release();
                    pSite = NULL;
                }
                
                pMainContext->SetErrorStatus( hr );
                pMainContext->SetFinishedResponse();               
            }
            else
            {
                g_pW3Server->AddSite( pSite );
            }
        }

        g_pW3Server->WriteUnlockSiteList();
    }
    
    if ( pSite == NULL )
    {
        return CONTEXT_STATUS_CONTINUE;
    }
    
    //
    // If we found a site, associate it so that all future consumers can
    // get at site configuration settings
    //
    
    pMainContext->AssociateSite( pSite );

    //
    // Let the raw data fun begin. 
    //
    // If this request has gone thru the stream filter, then we'll need
    // to associate the current W3_CONNECTION with a RAW_CONNECTION.  Also,
    // we'll have to retrieve a filter context
    //
    
    fNeedRawRead = FILTER_LIST::QueryGlobalList()->IsNotificationNeeded(
                                                SF_NOTIFY_READ_RAW_DATA,
                                                FALSE );
    
    if ( pRequest->QueryRawConnectionId() != HTTP_NULL_ID &&
         fNeedRawRead )
    {
        //
        // Raw read filters should be loaded only in old mode
        //
        DBG_ASSERT( g_pW3Server->QueryInBackwardCompatibilityMode() );

        //
        // Find a raw connection for this request
        //

        hr = RAW_CONNECTION::FindConnection( pRequest->QueryRawConnectionId(),
                                             &pRawConnection );
        if ( FAILED( hr ) )
        {
            pMainContext->SetErrorStatus( hr ); 
            pMainContext->SetFinishedResponse();
            pMainContext->SetDisconnect( TRUE );
            return CONTEXT_STATUS_CONTINUE;
        }  
        
        DBG_ASSERT( pRawConnection != NULL );                         
        
        //
        // We will need to copy over context pointers and allocated memory
        // from any existing read data filters
        // 
        
        pFilterContext = pMainContext->QueryFilterContext();
        if ( pFilterContext == NULL )
        {
            pMainContext->SetErrorStatus( hr ); 
            pMainContext->SetFinishedResponse();
            pMainContext->SetDisconnect( TRUE );
            return CONTEXT_STATUS_CONTINUE;
        }
        
        pRawConnection->CopyContextPointers( pFilterContext );
        pRawConnection->CopyAllocatedFilterMemory( pFilterContext );
        
        hr = pRawConnection->CopyHeaders( pFilterContext );
        if ( FAILED( hr ) )
        {
            pMainContext->SetErrorStatus( hr ); 
            pMainContext->SetFinishedResponse();
            pMainContext->SetDisconnect( TRUE );
            return CONTEXT_STATUS_CONTINUE;
        }

        //
        // Associate the raw connection with the main context
        //
        
        pRawConnection->SetMainContext( pMainContext );
        pMainContext->SetRawConnection( pRawConnection );
    }    
    
    //
    // We can notify filters now that we have a site associated
    //
    
    if ( pMainContext->IsNotificationNeeded( SF_NOTIFY_PREPROC_HEADERS ) )
    {
        pMainContext->NotifyFilters( SF_NOTIFY_PREPROC_HEADERS,
                                     NULL,
                                     &fFinished );
        
        if ( fFinished )
        {
            pMainContext->SetFinishedResponse();
        }
    }

    //
    // Determine the amount of bytes available to be read thru UL
    //
    
    pMainContext->DetermineRemainingEntity();
    
    //
    // Now that filters have been notified, we can increment the appropriate
    // verb perf counter.
    //
    
    pSite->IncReqType( pRequest->QueryVerbType() );
    
    return CONTEXT_STATUS_CONTINUE;
}

VOID *
W3_MAIN_CONTEXT_STATE::operator new(
    size_t              uiSize,
    VOID *              pPlacement
)
{
    W3_MAIN_CONTEXT *           pContext;
    W3_MAIN_CONTEXT_STATE *     pState;
    PVOID                       pBuffer;
    
    pContext = (W3_MAIN_CONTEXT*) pPlacement;
    DBG_ASSERT( pContext != NULL );
    DBG_ASSERT( pContext->CheckSignature() );

    pBuffer = pContext->ContextAlloc( (UINT)uiSize );
    DBG_ASSERT( pBuffer != NULL );
    return pBuffer;
}
    
VOID
W3_MAIN_CONTEXT_STATE::operator delete(
    VOID *              pContext
)
{
    //
    // Do nothing here.  Either
    // a) memory was allocated from inline W3_MAIN_CONTEXT buffer and thus should
    //    not be freeed
    // b) memory was allocated from heap because inline buffer didn't have
    //    enough space.  In this case, the memory is freed on MAIN_CONTEXT
    //    cleanup
    //
}

VOID
W3_MAIN_CONTEXT::DetermineRemainingEntity(
    VOID
)
/*++

Routine Description:

    Determine remaining entity body to be read from UL

Arguments:

    None

Return Value:

    None

--*/
{
    CHAR *                  pszContentLength;
    DWORD                   cbContentLength;
    
    if ( _request.QueryMoreEntityBodyExists() )
    {
        pszContentLength = _request.GetHeader( HttpHeaderContentLength );
        if ( pszContentLength != NULL )
        {
            cbContentLength = atoi( pszContentLength );
            
            if ( _request.QueryAvailableBytes() <= cbContentLength )
            {
                _cbRemainingEntityFromUL = cbContentLength - _request.QueryAvailableBytes();
            } 
            else
            {
                _cbRemainingEntityFromUL = 0;
            }
        }
        else
        {
            _cbRemainingEntityFromUL = INFINITE;
        }
    }
    else
    {
        _cbRemainingEntityFromUL = 0;
    }
}

HRESULT
W3_MAIN_CONTEXT::SetupCertificateContext(
    HTTP_SSL_CLIENT_CERT_INFO * pClientCertInfo
)
/*++

Routine Description:

    Create a CERTIFICATE_CONTEXT representing the given client certificate

Arguments:

    pClientCertInfo - Client cert info from stream filter

Return Value:

    HRESULT

--*/
{
    if ( pClientCertInfo == NULL )
    {
        DBG_ASSERT( FALSE );
        return HRESULT_FROM_WIN32( ERROR_INVALID_PARAMETER );
    }
    
    //
    // Just for completeness sake, attach the raw cert descriptor to the
    // main request, as it automatically be for subsequent requests on this
    // connection
    //
    
    QueryRequest()->SetClientCertInfo( pClientCertInfo );

    //
    // Create a client certificate descriptor and associate it with
    //
    
    DBG_ASSERT( _pCertificateContext == NULL );
    
    _pCertificateContext = new CERTIFICATE_CONTEXT( pClientCertInfo );
    if ( _pCertificateContext == NULL )
    {
        return HRESULT_FROM_WIN32( GetLastError() );
    }
    
    return NO_ERROR;
}

VOID
W3_MAIN_CONTEXT::SetRawConnection(
    RAW_CONNECTION *            pRawConnection
)
/*++

Routine Description:

    Set a raw connection for this context.  This raw connection is stored so
    that we can disassociate ourselves with it when the state machine is
    complete

Arguments:

    pRawConnection - Raw connection

Return Value:

    None

--*/
{
    pRawConnection->ReferenceRawConnection();
    _pRawConnection = pRawConnection;
}

CONTEXT_STATUS
W3_STATE_DONE::DoWork(
    W3_MAIN_CONTEXT *       pMainContext,
    DWORD                   cbCompletion,
    DWORD                   dwCompletionStatus
)
/*++

Routine Description:

    Do the done state stuff

Arguments:

    pMainContext - W3_MAIN_CONTEXT representing an execution of the state machine
    cbCompletion - Number of bytes on completion
    dwCompletionStatus - Win32 Error on completion (if any)
    
Return Value:

    CONTEXT_STATUS_CONTINUE - if we should continue in state machine
    else stop executing the machine and free up the current thread

--*/
{
    return CONTEXT_STATUS_CONTINUE;
}

CONTEXT_STATUS
W3_STATE_DONE::OnCompletion(
    W3_MAIN_CONTEXT *       pMainContext,
    DWORD                   cbCompletion,
    DWORD                   dwCompletionStatus
)
/*++

Routine Description:

    Complete the done state

Arguments:

    pMainContext - W3_MAIN_CONTEXT representing an execution of the state machine
    cbCompletion - Number of bytes on completion
    dwCompletionStatus - Win32 Error on completion (if any)
    
Return Value:

    CONTEXT_STATUS_CONTINUE - if we should continue in state machine
    else stop executing the machine and free up the current thread

--*/
{
    DBG_ASSERT( pMainContext != NULL );
    
    //
    // We could only get to here, if a send raw notification caused us to
    // pend the done state until the connection goes away, or the current
    // context is disassociated with the connection
    //
    
    DBG_ASSERT( pMainContext->IsNotificationNeeded( SF_NOTIFY_SEND_RAW_DATA ) );

    return CONTEXT_STATUS_CONTINUE;
}

//static
VOID
W3_MAIN_CONTEXT::OnNewRequest(
    ULATQ_CONTEXT          ulatqContext
)
/*++

Routine Description:

    Completion routine called when a new request is dequeued to be handled

Arguments:

    ulatqContext - ULATQ_CONTEXT representing the request
    
Return Value:

    None

--*/
{
    HTTP_REQUEST *          pUlHttpRequest = NULL;
    W3_CONNECTION *         pConnection = NULL;
    W3_MAIN_CONTEXT *       pMainContext = NULL;
    HRESULT                 hr = NO_ERROR;

    InterlockedIncrement( &sm_cOutstandingThreads );
    
    //
    // Get the HTTP_REQUEST for this new request
    //
    
    pUlHttpRequest = (HTTP_REQUEST *)UlAtqGetContextProperty(
                                         ulatqContext,
                                         ULATQ_PROPERTY_HTTP_REQUEST );

    DBG_ASSERT( pUlHttpRequest != NULL );

    //
    // Setup the MAIN_CONTEXT for this new request
    //

    pMainContext = new W3_MAIN_CONTEXT( pUlHttpRequest,
                                        ulatqContext );
    
    if (NULL == pMainContext)
    {
        UlAtqFreeContext(ulatqContext);
        goto done;
    }

    pMainContext->_LogContext.m_dwBytesRecvd = pUlHttpRequest->BytesReceived;

    //
    // Start the state machine
    //
    
    pMainContext->DoWork( 0, 
                          0, 
                          FALSE );

done:                          
    InterlockedDecrement( &sm_cOutstandingThreads );
}

//static
VOID
W3_MAIN_CONTEXT::OnPostedCompletion(
    DWORD           dwCompletionStatus,
    DWORD           cbTransferred,
    LPOVERLAPPED    lpo
)
/*++

Routine Description:

    Fake completion routine called when we want to fake a completion for
    asynchronous sanity sake

Arguments:

    dwCompletionStatus - Error (if any) on the completion
    cbTransferred - Bytes Written
    lpo - Overlapped
    
Return Value:

    None

--*/
{
    W3_MAIN_CONTEXT *    pMainContext;

    InterlockedIncrement( &sm_cOutstandingThreads );

    pMainContext = (W3_MAIN_CONTEXT *)lpo;
    DBG_ASSERT( pMainContext != NULL );

    //
    // Continue the state machine
    //
    
    pMainContext->DoWork( cbTransferred,
                          dwCompletionStatus,
                          TRUE );
                          
    InterlockedDecrement( &sm_cOutstandingThreads );
}

//static
VOID
W3_MAIN_CONTEXT::OnIoCompletion(
    PVOID                   pvContext,
    DWORD                   cbTransferred,
    DWORD                   dwCompletionStatus,
    OVERLAPPED *            lpo
)
/*++

Routine Description:

    Completion routine called on async IO completions for a given request

Arguments:

    pvContext - Completion context (a UL_REQUEST*)
    cbTransferred - Bytes on the completion
    dwCompletionStatus - Error (if any) on the completion
    lpo - Overlapped
    
Return Value:

    None

--*/
{
    W3_MAIN_CONTEXT *            pMainContext;

    InterlockedIncrement( &sm_cOutstandingThreads );
    
    pMainContext = (W3_MAIN_CONTEXT*) pvContext;
    DBG_ASSERT( pMainContext != NULL );
    DBG_ASSERT( pMainContext->CheckSignature() );

    //
    // Continue the state machine
    //
    
    pMainContext->DoWork( cbTransferred,
                          dwCompletionStatus,
                          TRUE );
                          
    InterlockedDecrement( &sm_cOutstandingThreads );
}

//static
VOID
W3_MAIN_CONTEXT::AddressResolutionCallback(
    ADDRCHECKARG            pContext,
    BOOL                    fUnused,
    LPSTR                   pszUnused
)
/*++

Routine Description:

    Callback called when RDNS crud has done its resolution

Arguments:

    pContext - Context (in our case, pointer to W3_MAIN_CONTEXT so that 
                        we can resume state machine)
    fUnused - Not used
    pszUnused - Not used
    
Return Value:

    None

--*/
{
    W3_MAIN_CONTEXT *           pMainContext;
    
    pMainContext = (W3_MAIN_CONTEXT*) pContext;
    DBG_ASSERT( pMainContext != NULL );
    DBG_ASSERT( pMainContext->CheckSignature() );
    
    ThreadPoolPostCompletion( 0,
                              W3_MAIN_CONTEXT::OnPostedCompletion,
                              (OVERLAPPED*) pMainContext );
}

VOID
W3_MAIN_CONTEXT::TimerCallback(LPVOID pvParam,
                             BOOLEAN fReason)
/*++

Routine Description:

    Callback called when W3_MAIN_CONTEXT has existed for too long

    OutputDebugString to tell people why we are doing this
    and DebugBreak if a debugger is attached.  
    
    If no debugger is attached, ignore the callback.

Arguments:

    pvParam - pointer to W3_MAIN_CONTEXT that has exceeded its maximum lifetime
    fReason - not used
    
Return Value:

    void

--*/
{
    W3_MAIN_CONTEXT* pThis = (W3_MAIN_CONTEXT*)pvParam;
    if (IsDebuggerPresent())
    {
        OutputDebugString(L"****************\nIIS (w3core.dll) has called DebugBreak because\nHKLM\\System\\CurrentControlSet\\Services\\InetInfo\\Parameters\\RequestTimeoutBreak\nwas set.\nAnd a request has taken longer than the specified maximium time in milliseconds\n****************\n");
        DebugBreak();
    }

    return;
}