Chapter 1

aStart.SignalL();
CActiveScheduler::Start();
// Destroy the scheduler
#endif
CleanupStack::PopAndDestroy(self);
}
First ConstructL() creates a real active scheduler and installs it as the thread's current
scheduler. This essentially stores a pointer to the scheduler in a special location reserved by
the kernel. You can get at this pointer using CActiveScheduler::Current() if you need
to. Next the server object is constructed and stored in the iServer member. Finally, the
client is signaled to indicate that the startup has succeeded. Then all that remains to do is to
start the active scheduler, which starts the server processing requests.
CActiveScheduler::Start() does not return until CActiveScheduler::Stop() is
called – we'll see how this happens below.
Server construction
By the time we get to the CGsdpServer construction, we are in normal C++ territory: we
have a cleanup stack and active scheduler, we don't have to think about the thread that's
launched us – in short, the code has lost the flavor of a bootstrap. CGsdpServer's C++
constructor passes two parameters down to the base CServer constructor: a zero active
object priority, and flag specifying that sessions can be shared:
CGsdpServer::CGsdpServer() : CServer(0, EShareableSessions)
{
}
This indicates that the server does not have a higher or lower priority than any other active
object in the thread, and that the server sessions can be shared between all threads in a
process. By default, a session can only be used by the thread that creates it. Sharing
sessions between threads is a useful facility that servers should support if possible, so we
enable this here. The main work of construction is handled by
CGsdpServer::ConstructL() which we looked at earlier.
Server shutdown
The server shuts down 2 s after its last client session is closed. The server keeps a count of
client sessions using IncrementSessions() and DecrementSessions(), which are
called from NewSessionL() and from the session destructor:
void CGsdpServer::IncrementSessions()
{
iSessionCount++;
iShutdown->Cancel();
}
void CGsdpServer::DecrementSessions()
{
iSessionCount--;
if(iSessionCount > 0)