INF: Building an ODS Application with MFC

• Microsoft SQL Server versions 4.2x, 6.0, 6.5

SUMMARY

This article describes the steps necessary to build an ODS application using MFC. The major issue is that without the _cdecl specifications, the C++ compiler cannot locate the standard C API calls.

1. Wrap the following code around the include of the Srv.h header file:
   

   
            #ifdef __cplusplus
               extern "C" {
            #endif
   
         #include <srv.h>
   
            #ifdef __cplusplus
               }
            #endif
    




2. If you are developing a non-console application, you should start a separate thread to call srv_start. This frees the main thread to handle Windows message processing activity. The following lines provide a small example:
   

   
         DWORD dwThread =  0;
   
         hThread = CreateThread(NULL, 0 ,
      (LPTHREAD_START_ROUTINE)iServerRunThread, NULL, 0, &dwThread);
         if(!hThread)
            ... Error processing ...
   
         int iServerRunThread(void)
         {
            srv_run(pDlg->pserver);
            return 1;
         }
    




3. Cast your calls to install event handlers as shown by the following:
   

   
         srv_handle(pserver, SRV_START, (int (__cdecl *)(void *))
            iODSEventHandler);
    

BOOL CODSSampleDlg::OnInitDialog()
{
   CDialog::OnInitDialog();
   pDlg = this;

   // Add "About..." menu item to system menu.
   // IDM_ABOUTBOX must be in the system command range.
   ASSERT((IDM_ABOUTBOX & 0xFFF0) == IDM_ABOUTBOX);
   ASSERT(IDM_ABOUTBOX < 0xF000);
   CMenu* pSysMenu = GetSystemMenu(FALSE);
   CString strAboutMenu;
   strAboutMenu.LoadString(IDS_ABOUTBOX);
   if (!strAboutMenu.IsEmpty())
   {
      pSysMenu->AppendMenu(MF_SEPARATOR);
      pSysMenu->AppendMenu(MF_STRING, IDM_ABOUTBOX, strAboutMenu);
   }
   // Set the icon for this dialog.  The framework does this automatically
   //  when the application's main window is not a dialog
   SetIcon(m_hIcon, TRUE);       // Set big icon
   SetIcon(m_hIcon, FALSE);      // Set small icon

   // ************************************************
   //    BEGIN:   ODS Code Initialization
   // ************************************************

   if(pconfig = srv_config_alloc())
   {
      if(srv_config(pconfig, SRV_ANSI_CODEPAGE, "TRUE", SRV_NULLTERM) ==
        SUCCEED)
      {
         if(srv_config(pconfig, SRV_MINWORKINGTHREADS, "10", SRV_NULLTERM)
           == SUCCEED)
         {
            if(srv_config(pconfig, SRV_MAXWORKINGTHREADS, "25",
               SRV_NULLTERM) == SUCCEED)
            {
               if(srv_config(pconfig, SRV_THREADTIMEOUT, "1", SRV_NULLTERM)
                  == SUCCEED)
               {
                  srv_errhandle(iODSErrorHandler);
                  if(pserver = (PSRV_SERVER) srv_init(pconfig, "ODS",
                     SRV_NULLTERM))
                  {
                     vAddLine(">>> ODS Sample Starting.");
                     srv_handle(pserver, SRV_START, (int (__cdecl *)(void
                        *))iODSEventHandler);

                     // 
                     // Lets get things started
                     // 
                     DWORD dwThread =  0;
                     hThread = CreateThread(NULL, 0 ,
                       (LPTHREAD_START_ROUTINE)iServerRunThread, NULL, 0, &dwThread);
                     if(!hThread)
                        vAddLine("*** attempt to start ODS server thread failed.");
                  }
                  else
                     vAddLine("*** attempt to initialize server failed.");
               }
               else
                  vAddLine("*** attempt to set thread timeout failed.");
            }
            else
               vAddLine("*** attempt to set max worker threads failed.");
         }
         else
            vAddLine("*** attempt to set min worker threads failed.");
      }
      else
         vAddLine("*** attempt to set ANSI codepage failed.");
   }
   else
      vAddLine("*** srv_config_alloc() failed.");

   // ************************************************
   //    END:  ODS Code Initialization
   // ************************************************

   return TRUE;  // return TRUE  unless you set the focus to a control
}
#ifdef __cplusplus
   extern "C" {
#endif

// 
//    ODS Handlers
// 
int iODSErrorHandler(PSRV_SERVER pserver, PSRV_PROC psrvproc, int iErrorNo,
BYTE bSeverity,
                BYTE bState, int iOSErrorNo, DBCHAR * strError, int
iErrorLen, DBCHAR *strOSError, int iOSErrorLen)
{
   CString     cstrError;
   int   iRc = SRV_CONTINUE;
    pDlg->vAddLine("");
   cstrError.Format("*** OS Error %d: %s.", iOSErrorNo, strOSError);
   pDlg->vAddLine((LPCTSTR)cstrError);
   cstrError.Format("*** Error: (%d) Sev: (%d) State: (%d) %s.", iErrorNo,
      bSeverity, bState, strError);
   pDlg->vAddLine((LPCTSTR)cstrError);
   pDlg->vAddLine("");
   return iRc;
}
int iODSEventHandler(PSRV_SERVER pserver)
{
   pDlg->vAddLine(">>> SRV_START called.");

   // 
   //    Setup ODS handlers
   // 
   srv_handle(pserver, SRV_CONNECT, (int (__cdecl *)(void *))
iConnectionHandler);

   //   srv_handle(pserver, SRV_LANGUAGE, iLangExecHandler);
   //   srv_handle(pserver, SRV_DISCONNECT, iExitConnectHandler);
   //   srv_handle(pserver, SRV_ATTENTION, iAttentionHandler);

   return(SRV_CONTINUE);
}
int iServerRunThread(void)
{
   srv_run(pDlg->pserver);

   return 1;
}
int iConnectionHandler(PSRV_PROC psrvproc)
{
   CString     cstrData;

   EnterCriticalSection(&pDlg->csSync);

   cstrData.Format(">>> User name ............ \"%s\"",
srv_pfield(psrvproc, SRV_USER, NULL));
   pDlg->vAddLine((LPCTSTR)cstrData);
   cstrData.Format(">>> Password ............. \"%s\"",
srv_pfield(psrvproc, SRV_PWD, NULL));
   pDlg->vAddLine((LPCTSTR)cstrData);
   LeaveCriticalSection(&pDlg->csSync);
   return SRV_DISCONNECT;
}
#ifdef __cplusplus
   }
#endif 

Keywords : kbprg kbusage SSrvODS SSrvProg
Version : 4.21 6.0 6.5
Platform : WINDOWS
Issue type : kbhowto