Ok I will control my code again but I couldnt understand exacly below..
"Your queuing code already does that, but you are not protecting your room array itself."
Q1- why?
Troom=class
name: String;
kritiklist: TThreadlist;
xlist: Tthreadlist;
constructor create(name:string);
end;
project oncreate:
rooms: array of Troom;
setlength(rooms, myvalue);
for i := 0 to myvalue-1 do rooms := Troom.create(names[i]);
rooms[ 1 ].kritiklist.locklist ---> for example alot of threads can access this line in the same time.But I think this does not cause any problem? is it true?
I think it is not necessary protect rooms array because rooms variables of rooms array are threadlist.But I am not sure..
Only one variable( name:string ) is not being protect because it does not change any where.It is set only one in project oncreate. All threads only read this value if necessary.
Q2-
procedure TfrmTcpserver.ServerDisconnect(AThread:TIdPeerThread);
begin
TMypeerthread( Athread ).fromOnthisconnect := true;//it's value is false in Tmypeerthread creating method.
.......
end;
destructor TMyPeerThread.Destroy;
begin
if fromOnthisconnect = false then savetolog('interesting');
....
end;
When I check log file for example I see 70 lines 'interesting' expression for 10 seconds.What about this?
when the user try to connect the server and if the connection is not ensured than onthisconnect event is not called and TMypeerthread will free.is it true? Or TMypeerthread class is created only if connection is established otherwise TMypeerthread is not created or free by indy.
So is this a problem? if it is a problem what about this?
many thanks.
"Remy Lebeau \(TeamB\)" <no.spam@no.spam.com> wrote:
>
>"emre varol" <none@none.com> wrote in message
>news:47b16bb3$1@newsgroups.borland.com...
>
>> Some times only one exception occurs. This is 'test2' exception that in
>> the AddToQueue function. Access violation at address 7C81A379 in
>> module 'ntdll.dll'. Write of address Test2 exception is related with
>> FQueue threadlist.
>
>Then clearly your code is not protecting itself adequately enough from
>concurrency issues. EVERYWHERE that two connections can access the same
>resource at potentially the same time, you need to have a lock for it. Your
>queuing code already does that, but you are not protecting your room array
>itself.
>
>> if KAth.AddToQueue( stream ) ----> if KAth has been free
>
>The only way that can happen is if you did not remove the thread from the
>room's list before another thread tried to send data to that thread. All
>the more reason to think that you are not serializing access to your rooms
>good enough to prevent invalid pointers from being passed around.
>
>> how can we go to its function(AddToQueue) if KAth has been free
>
>From the CPU's perspective, calling an object method is no different than
>calling a standalone procedure. The memory address of the method is static.
>The compiler jumps to the same place each time. The only difference is that
>a method has a hidden Self parameter whereas a standalone procedure does
>not. It doesn't matter what the Self pointer value actually is at the time
>of the calling. The method itself can still be called regardless of whether
>the object is valid or not. You won't get a crash or the like until the
>Self pointer is dereferenced to access one of its data members.
>
>> In the TMyPeerThread.Destroy method FQueue threadlist is being free.
>> But this TMyPeerThread class is being removed from rooms[ no ].kritiklist
>> in ServerDisconnect event.
>
>Then your problem is somewhere else.
>
>> if ServerDisconnect event is not called by indy
>
>It will be.
>
>> But in which cases Indy dont call ServerDisconnect event
>
>The OnDisconnect event will always be called.
>
>> And FQueue variable are being free only in TMyPeerThread.Destroy method.
>> if destroy method occurs how can we call KAth.AddToQueue method?
>
>Like I said, the only way that could happen is if you have not yet removed
>the thread from the room list before AddToQueue() is called again
>
>
>Gambit
