/// <summary>
/// Aborts a transaction on this server
/// </summary>
/// <param name="tid">transaction identifier</param>
/// <param name="usedPadInts">Identifiers of PadInts involved</param>
/// <returns>A predicate confirming the sucess of the operations</returns>
internal override bool Abort(int tid, List <int> usedPadInts)
{
Logger.Log(new String[] { "PrimaryServer", Server.ID.ToString(), "abort", "tid", tid.ToString() });
bool resultAbort = true;
try {
VerifyPadInts(usedPadInts);
foreach (int padIntUid in usedPadInts)
{
PadInt padInt = GetPadInt(padIntUid);
resultAbort = padInt.Abort(tid) && resultAbort;
}
} catch (PadIntNotFoundException) {
throw;
}
/* updates the backup server */
backupReplyTimer.Start();
BackupServer.Abort(tid, usedPadInts);
backupReplyTimer.Stop();
return(resultAbort);
}
/// <summary>
/// Writes a value in a PadInt
/// </summary>
/// <param name="tid">Transaction identifier</param>
/// <param name="uid">PadInt identifier</param>
/// <param name="value">Value of the write</param>
/// <returns>True if successful</returns>
internal override bool WritePadInt(int tid, int uid, int value)
{
Logger.Log(new String[] { "Server ", Server.ID.ToString(), " writePadInt ", "tid", tid.ToString(), "uid", uid.ToString(), "value", value.ToString() });
try {
/* Obtain the PadInt identified by uid */
PadInt padInt = GetPadInt(uid);
while (true)
{
if (padInt.GetWriteLock(tid))
{
padInt.ActualValue = value;
/* updates the backup server */
backupReplyTimer.Start();
BackupServer.WritePadInt(tid, uid, value);
backupReplyTimer.Stop();
return(true);
}
}
} catch (PadIntNotFoundException) {
throw;
} catch (AbortException) {
throw;
}
}
/// <summary>
/// Returns the value of the PadInt when the transaction has the read/write lock.
/// Throws an exception if PadInt not found.
/// </summary>
/// <param name="tid">Transaction identifier</param>
/// <param name="uid">PadInt identifier</param>
/// <returns></returns>
internal override int ReadPadInt(int tid, int uid)
{
Logger.Log(new String[] { "PrimaryServer", Server.ID.ToString(), "readPadInt ", "tid", tid.ToString(), "uid", uid.ToString() });
try {
/* Obtain the PadInt identified by uid */
PadInt padInt = GetPadInt(uid);
while (true)
{
if (padInt.HasWriteLock(tid) || padInt.GetReadLock(tid))
{
/* updates the backup server */
backupReplyTimer.Start();
BackupServer.ReadPadInt(tid, uid);
backupReplyTimer.Stop();
return(padInt.ActualValue);
}
}
} catch (PadIntNotFoundException) {
throw;
} catch (AbortException) {
throw;
}
}
/// <summary>
/// Sends I'm alive to backup server
/// </summary>
internal override void ImAlive()
{
Logger.Log(new String[] { "PrimaryServer", Server.ID.ToString(), "ImAlive" });
imAliveTimer.Stop();
BackupServer.ImAlive();
//re-starts the timer
imAliveTimer.Start();
}
/// <summary>
/// Deals with backup reply timer events
/// </summary>
private void BackupReplyEvent(object source, ElapsedEventArgs e)
{
Logger.Log(new String[] { "PrimaryServer", Server.ID.ToString(), "BackupReplyEvent" });
backupReplyTimer.Stop();
backupReplyTimer.Close();
imAliveTimer.Stop();
imAliveTimer.Close();
IServerMachine backupServerMachine = (IServerMachine)Activator.GetObject(typeof(IServerMachine), BackupAddress + "Machine");
backupServerMachine.RestartServer();
BackupServer.CreateBackupServer(Server.Address, padIntDictionary, false);
}
/// <summary>
/// Create a PadInt identified by uid
/// </summary>
/// <param name="uid">PadInt identifier</param>
/// <returns></returns>
internal override bool CreatePadInt(int uid)
{
Logger.Log(new String[] { "PrimaryServer", Server.ID.ToString(), "createPadInt", "uid ", uid.ToString(),
" NPadInts", (padIntDictionary.Count + 1).ToString() });
try {
padIntDictionary.Add(uid, new PadInt(uid));
/* updates the backup server */
backupReplyTimer.Start();
BackupServer.CreatePadInt(uid);
backupReplyTimer.Stop();
return(true);
} catch (ArgumentException) {
throw new PadIntAlreadyExistsException(uid, Server.ID);
}
}
public override bool Status()
{
base.Status();
BackupServer.Status();
return(true);
}
