/***************************************************************************/
/* "Mario Paranhos" <mxp@bravepoint.com> as released on peg                */
/***************************************************************************/

FUNCTION pingHost RETURNS LOGICAL (INPUT chrDBHost AS CHARACTER):
  DEFINE VARIABLE pingResponse AS CHARACTER NO-UNDO.
  DEFINE VARIABLE pingValidResponseUNIX AS CHARACTER NO-UNDO.
  DEFINE VARIABLE pingValidResponseNT AS CHARACTER NO-UNDO.
  DEFINE VARIABLE pingValidResponse AS CHARACTER NO-UNDO.
  DEFINE VARIABLE pingUNIX AS CHARACTER NO-UNDO.
  DEFINE VARIABLE pingNT AS CHARACTER NO-UNDO.
  DEFINE VARIABLE pingCMD AS CHARACTER NO-UNDO.
  DEFINE VARIABLE pingTimeOut AS INTEGER NO-UNDO.
  DEFINE VARIABLE hostAlive AS LOGICAL NO-UNDO.

  ASSIGN pingValidResponseUNIX = "9 bytes from"
         pingValidResponseNT = "Reply from"
         pingTimeOut = 50 /* Windows is in milliseconds, UNIX seconds */
         pingNT = "ping -l 1 -n 1 -w " + STRING(pingTimeOut) + " " +
chrDBHost.
         pingUNIX = "ping -s 1 -c 1 -w " + STRING(pingTimeOut) + " " +
chrDBHost.
         .

  IF "{&opsys}" = "UNIX" THEN
    ASSIGN pingCMD = pingUNIX
           pingValidResponse = pingValidResponseUNIX.
  ELSE
    ASSIGN pingCMD = pingNT
           pingValidResponse = pingValidResponseNT.

  INPUT THROUGH VALUE(pingCMD).
  pingLoop:
  REPEAT:
    IMPORT UNFORMATTED pingResponse.
    IF pingResponse BEGINS pingValidResponse THEN
    DO:
      ASSIGN hostAlive = TRUE.
      LEAVE pingLoop.
    END.
  END.
  INPUT CLOSE.

  RETURN hostAlive.
END FUNCTION. /* pingHost */

FUNCTION serverIsUp RETURN LOGICAL (INPUT pServer AS CHARACTER,
                                   INPUT pPort AS CHARACTER):
  DEFINE VARIABLE hSocket AS HANDLE  NO-UNDO.
  DEFINE VARIABLE lStatus AS LOGICAL NO-UNDO.

  CREATE SOCKET hSocket.
  ASSIGN lStatus = hSocket:CONNECT("-H " + pServer + " -S " + pPort)
NO-ERROR.
  hSocket:DISCONNECT().
  DELETE OBJECT hSocket.
  ASSIGN hSocket = ?.
  RETURN lStatus.
END FUNCTION. /* serverIsUp */


FUNCTION connectDB RETURNS LOGICAL (INPUT chrDBName AS CHARACTER,
                                    INPUT chrDBHost AS CHARACTER,
                                    INPUT chrDBService AS CHARACTER):
  IF NOT pingHost(chrDBHost) THEN
    RETURN FALSE.

  IF NOT serverIsUp(chrDBHost,chrDBService) THEN
    RETURN FALSE.

  CONNECT VALUE(chrDBName) -H VALUE(chrDBHost) -S VALUE(chrDBService) -N TCP
NO-ERROR.
  IF ERROR-STATUS:ERROR THEN
    RETURN FALSE.

  RETURN TRUE.
END FUNCTION. /* connectDB */


MESSAGE string(connectDB("DBNAME","IP","PORT")) VIEW-AS ALERT-BOX.

/***************************************************************************/