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// $Id$
#ifndef _CLIENT_HANDLER_H
#define _CLIENT_HANDLER_H
/*
A connection handler will also be derived from ACE_Event_Handler so that we
can register with a reactor.
*/
#include "ace/Event_Handler.h"
#if !defined (ACE_LACKS_PRAGMA_ONCE)
# pragma once
#endif /* ACE_LACKS_PRAGMA_ONCE */
#include "ace/INET_Addr.h"
/*
Since we're doing TCP/IP, we'll need a SOCK_Stream for the connection.
*/
#include "ace/SOCK_Stream.h"
class Logging_Handler : public ACE_Event_Handler
{
public:
/*
Like the acceptor, we're simple enough to avoid constructor and destructor.
*/
/*
To open the client handler, we have to register ourselves with the reactor.
Notice that we don't have to "open" our ACE_SOCK_Stream member variable.
Why? Because the call to the acceptor's accept() method took care of those
details for us.
*/
int open ( ACE_Reactor * _reactor )
{
/*
Remember our reactor...
*/
reactor_ = _reactor;
/*
In this case we're using the READ_MASK. Like the acceptor, handle_input()
will be called due to this mask but it's a nice piece of bookkeeping to
have separate masks for the separate types of activity.
*/
if (_reactor-> register_handler (this, ACE_Event_Handler::READ_MASK) == -1)
ACE_ERROR_RETURN ((LM_ERROR, "(%P|%t) can't register with reactor\n"), -1);
return 0;
}
/*
If we're explicitly closed we'll close our "file handle". The net result
is to close the connection to the client and remove ourselves from the
reactor if we're registered
*/
int close (void)
{
return this->handle_close (ACE_INVALID_HANDLE, ACE_Event_Handler::RWE_MASK);
}
/*
This is a bit of magic... When we call the accept() method of the acceptor
object, it wants to do work on an ACE_SOCK_Stream. We have one of those as
our connection to the client but it would be gross to provide a method to
access that object. It's much cooler if the acceptor can just treat the
Logging_Handler as an ACE_SOCK_Stream. Providing this cast operator lets
that happen cleanly.
*/
operator ACE_SOCK_Stream &()
{
return this->cli_stream_;
}
protected:
/*
Again, like the acceptor, we need to provide the connection handle to the reactor.
*/
ACE_HANDLE get_handle (void) const
{
return this->cli_stream_.get_handle ();
}
/*
And here's the handle_input(). This is really the workhorse of the application.
*/
int handle_input (ACE_HANDLE)
{
/*
Create and initialize a small receive buffer.
*/
char buf[128];
memset(buf,0,sizeof(buf));
/*
Invoke the recv() method of the ACE_SOCK_Stream to get some data. It will
return -1 if there is an error. Otherwise, it will return the number of bytes
read. Of course, if it read zero bytes then the connection must be gone.
How do I know that? Because handle_input() would not be called by the reactor
if there wasn't *some* kind of activity and a closed connection looks like a
read request to the reactor. But when you read from a closed connection you'll
read zero bytes.
Notice that in the error case or closed case we return -1. That tells the reactor
to call our handle_close() where we'll take care of shutting down cleanly.
*/
switch( this->cli_stream_.recv(buf,sizeof buf) )
{
case -1:
ACE_ERROR_RETURN ((LM_ERROR, "(%P|%t) %p bad read\n", "client logger"), -1);
case 0:
ACE_ERROR_RETURN ((LM_ERROR, "(%P|%t) closing log daemon (fd = %d)\n",
this->get_handle ()), -1);
default:
ACE_DEBUG ((LM_DEBUG, "(%P|%t) from client: %s",buf));
}
return 0;
}
/*
When handle_input() returns -1, we'll end up here. There are a few housekeeping
chores to handle.
*/
int handle_close (ACE_HANDLE, ACE_Reactor_Mask _mask)
{
/*
Remove ourselves from the reactor. We have to include the DONT_CALL in the
mask so that it won't call handle_close() on us again!
*/
reactor_->remove_handler(this,_mask|ACE_Event_Handler::DONT_CALL);
/*
Close the socket that we're connected to the client with.
*/
cli_stream_.close();
/*
Since we know we were dynamically allocated by the acceptor, now is a good
time to get rid of ourselves.
*/
delete this;
return 0;
}
protected:
/*
Our peer connection.
*/
ACE_SOCK_Stream cli_stream_;
/*
Our reactor (and our acceptor's reactor).
*/
ACE_Reactor * reactor_;
};
#endif /* _CLIENT_HANDLER_H */
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