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// $Id$
#if !defined (_CLIENT_ACCEPTOR_H)
#define _CLIENT_ACCEPTOR_H
/*
A SOCK_Acceptor knows how to accept socket connections. We'll use
one of those at the heart of our Logging_Acceptor.
*/
#include "ace/SOCK_Acceptor.h"
/*
An Event_Handler is what you register with ACE_Reactor. When events occur,
the reactor will callback on the Event_Handler. More on that in a few lines.
*/
#include "ace/Event_Handler.h"
/*
When a client connects, we'll create a Logging_Handler to deal with the
connection. Here, we bring in that declaration.
*/
#include "logger.h"
/*
Our Logging_Acceptor is derived from ACE_Event_Handler. That lets the
reactor treat our acceptor just like every other handler.
*/
class Logging_Acceptor : public ACE_Event_Handler
{
friend class Logging_Handler;
public:
/*
For this simple case we won't bother with either constructor or
destructor. In a real application you would certainly have them.
*/
/*
Here's the open() method we called from main(). We have two things
to accomplish here: (1) Open the acceptor so that we can hear
client requests and (2) register ourselves with the reactor so that
we can respond to those requests.
*/
int open (const ACE_INET_Addr &_addr, ACE_Reactor * _reactor )
{
/*
Perform the open() on the acceptor. We pass through the address
at which main() wants us to listen. The second parameter tells
the acceptor it is OK to reuse the address. This is necessary
sometimes to get around closed connections that haven't timed out.
*/
if (this->peer_acceptor_.open (_addr, 1) == -1)
return -1;
/*
Remember the reactor we're using. We'll need it later when we
create a client connection handler.
*/
reactor_ = _reactor;
/*
Now we can register with the reactor we were given. Since the reactor
pointer is global, we could have just used that but it's gross enough
already.
Notice that we can pass 'this' right into the registration since we're
derived from ACE_Event_Handler. We also provide ACCEPT_MASK to tell
the reactor that we want to know about accept requests from clients.
*/
return _reactor->register_handler( this, ACE_Event_Handler::ACCEPT_MASK );
}
private:
/*
To provide multi-OS abstraction, ACE uses the concept of "handles" for
connection endpoints. In Unix, this is a traditional file descriptor
(or integer). On other OS's, it may be something else.
The reactor will need to get the handle (file descriptor) to satisfy
it's own internal needs. Our relevant handle is the handle of the
acceptor object, so that's what we provide.
*/
ACE_HANDLE get_handle (void) const
{
return this->peer_acceptor_.get_handle ();
}
/*
When an accept request arrives, the reactor will invoke the handle_input()
callback. This is where we deal with the connection request.
*/
int handle_input (ACE_HANDLE)
{
/*
In response to the connection request, we create a new Logging_Handler.
This new object will be used to interact with the client until it
disconnects.
*/
Logging_Handler *svc_handler = new Logging_Handler;
/*
To complete the connection, we invoke the accept() method call on
the acceptor object and provide it with the connection handler instance.
This transfers "ownership" of the connection from the acceptor to the
connection handler.
*/
if (this->peer_acceptor_.accept (*svc_handler) == -1)
ACE_ERROR_RETURN ((LM_ERROR, "%p", "accept failed"), -1);
/*
Again, most objects need to be open()ed before they are useful. We'll
give the handler our reactor pointer so that it can register for
events as well. If the open fails, we'll force a close().
*/
if (svc_handler->open (reactor_) == -1)
svc_handler->close ();
return 0;
}
protected:
/*
Our acceptor object instance
*/
ACE_SOCK_Acceptor peer_acceptor_;
/*
A place to remember our reactor pointer
*/
ACE_Reactor * reactor_;
};
#endif /* _CLIENT_ACCEPTOR_H */
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