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+// $Id$
+
+/*
+ We try to keep main() very simple. One of the ways we do that is to push
+ much of the complicated stuff into worker objects. In this case, we only
+ need to include the acceptor header in our main source file. We let it
+ worry about the "real work".
+ */
+
+#include "client_acceptor.h"
+
+/*
+ As before, we create a simple signal handler that will set our finished
+ flag. There are, of course, more elegant ways to handle program shutdown
+ requests but that isn't really our focus right now, so we'll just do the
+ easiest thing.
+ */
+
+static sig_atomic_t finished = 0;
+extern "C" void handler (int)
+{
+ finished = 1;
+}
+
+/*
+ A server has to listen for clients at a known TCP/IP port. The default ACE
+ port is 10002 (at least on my system) and that's good enough for what we
+ want to do here. Obviously, a more robust application would take a command
+ line parameter or read from a configuration file or do some other clever
+ thing. Just like the signal handler above, though, that's what we want to
+ focus on, so we're taking the easy way out.
+ */
+
+static const u_short PORT = ACE_DEFAULT_SERVER_PORT;
+
+/*
+ Finally, we get to main. Some C++ compilers will complain loudly if your
+ function signature doesn't match the prototype. Even though we're not
+ going to use the parameters, we still have to specify them.
+ */
+
+int main (int argc, char *argv[])
+{
+/*
+ In our earlier servers, we used a global pointer to get to the reactor. I've
+ never really liked that idea, so I've moved it into main() this time. When
+ we get to the Client_Handler object you'll see how we manage to get a
+ pointer back to this reactor.
+ */
+ ACE_Reactor reactor;
+
+ /*
+ The acceptor will take care of letting clients connect to us. It will
+ also arrange for a Client_Handler to be created for each new client.
+ Since we're only going to listen at one TCP/IP port, we only need one
+ acceptor. If we wanted, though, we could create several of these and
+ listen at several ports. (That's what we would do if we wanted to rewrite
+ inetd for instance.)
+ */
+ Client_Acceptor peer_acceptor;
+
+ /*
+ Create an ACE_INET_Addr that represents our endpoint of a connection. We
+ then open our acceptor object with that Addr. Doing so tells the acceptor
+ where to listen for connections. Servers generally listen at "well known"
+ addresses. If not, there must be some mechanism by which the client is
+ informed of the server's address.
+
+ Note how ACE_ERROR_RETURN is used if we fail to open the acceptor. This
+ technique is used over and over again in our tutorials.
+ */
+ if (peer_acceptor.open (ACE_INET_Addr (PORT), &reactor) == -1)
+ ACE_ERROR_RETURN ((LM_ERROR, "%p\n", "open"), -1);
+
+ /*
+ Install our signal handler. You can actually register signal handlers
+ with the reactor. You might do that when the signal handler is
+ responsible for performing "real" work. Our simple flag-setter doesn't
+ justify deriving from ACE_Event_Handler and providing a callback function
+ though.
+ */
+ ACE_Sig_Action sa ((ACE_SignalHandler) handler, SIGINT);
+
+ /*
+ Like ACE_ERROR_RETURN, the ACE_DEBUG macro gets used quite a bit. It's a
+ handy way to generate uniform debug output from your program.
+ */
+ ACE_DEBUG ((LM_DEBUG, "(%P|%t) starting up server daemon\n"));
+
+ /*
+ This will loop "forever" invoking the handle_events() method of our
+ reactor. handle_events() watches for activity on any registered handlers
+ and invokes their appropriate callbacks when necessary. Callback-driven
+ programming is a big thing in ACE, you should get used to it. If the
+ signal handler catches something, the finished flag will be set and we'll
+ exit. Conveniently enough, handle_events() is also interrupted by signals
+ and will exit back to the while() loop. (If you want your event loop to
+ not be interrupted by signals, checkout the <i>restart</i> flag on the
+ open() method of ACE_Reactor if you're interested.)
+ */
+ while (!finished)
+ reactor.handle_events ();
+
+ ACE_DEBUG ((LM_DEBUG, "(%P|%t) shutting down server daemon\n"));
+
+ return 0;
+}