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diff --git a/docs/tutorials/005/page02.html b/docs/tutorials/005/page02.html deleted file mode 100644 index d453146c0ca..00000000000 --- a/docs/tutorials/005/page02.html +++ /dev/null @@ -1,158 +0,0 @@ -<HTML> -<HEAD> - <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> - <META NAME="GENERATOR" CONTENT="Mozilla/4.04 [en] (X11; I; Linux 2.0.32 i486) [Netscape]"> - <META NAME="Author" CONTENT="Billy Quinn"> - <META NAME="Description" CONTENT="A first step towards using ACE productively"> - <TITLE>ACE Tutorial 005</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 005</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>On the road to a multithreaded server</FONT></B></CENTER> - - -<P> -<HR WIDTH="100%"> - -<P>We begin with <I><A HREF="server.cpp">server.cpp</A></I>. -<P> -Abstraction by Kirthika: -<UL> -This tutorial is a re-cap of the client-server hookup tutorial with much - cleaner code (for instance: use of destroy() to delete objects and -process() which does the task of reading in data from the client). -<P> -We again enroll the services of the ACE_Reactor to handle events. Everything -occurs in a single thread. -<P> -This tutorial is a stepping stone towards a mutithreaded server model. -</ul> -<P> -<HR WIDTH="100%"> -<PRE> -<font color=red>// $Id$</font> - -<font color=red>/* - 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 "<font color=green>real work</font>". - */</font> - -<font color=blue>#include</font> "<font color=green>client_acceptor.h</font>" - -<font color=red>/* - 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. - */</font> - -static sig_atomic_t finished = 0; -extern "<font color=green>C</font>" void handler (int) -{ - finished = 1; -} - -<font color=red>/* - 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 not what we want to - focus on, so we're taking the easy way out. - */</font> - -static const u_short PORT = ACE_DEFAULT_SERVER_PORT; - -<font color=red>/* - 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. - */</font> - -int main (int argc, char *argv[]) -{ -<font color=red>/* - 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. - */</font> - ACE_Reactor reactor; - - <font color=red>/* - 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.) - */</font> - Client_Acceptor peer_acceptor; - - <font color=red>/* - 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 "<font color=green>well known</font>" - 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. - */</font> - if (peer_acceptor.open (ACE_INET_Addr (PORT), &reactor) == -1) - ACE_ERROR_RETURN ((LM_ERROR, "<font color=green>%p\n</font>", "<font color=green>open</font>"), -1); - - <font color=red>/* - Here, we know that the open was successful. If it had failed, we would - have exited above. A nice side-effect of the open() is that we're already - registered with the reactor we provided it. - */</font> - - <font color=red>/* - 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 "<font color=green>real</font>" work. Our simple flag-setter doesn't - justify deriving from ACE_Event_Handler and providing a callback function - though. - */</font> - ACE_Sig_Action sa ((ACE_SignalHandler) handler, SIGINT); - - <font color=red>/* - 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. - */</font> - ACE_DEBUG ((LM_DEBUG, "<font color=green>(%P|%t) starting up server daemon\n</font>")); - - <font color=red>/* - This will loop "<font color=green>forever</font>" 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 'restart' flag on the - open() method of ACE_Reactor if you're interested.) - */</font> - while (!finished) - reactor.handle_events (); - - ACE_DEBUG ((LM_DEBUG, "<font color=green>(%P|%t) shutting down server daemon\n</font>")); - - return 0; -} - -<font color=blue>#if defined</font> (<font color=purple>ACE_HAS_EXPLICIT_TEMPLATE_INSTANTIATION</font>) -template class ACE_Acceptor <Client_Handler, ACE_SOCK_ACCEPTOR>; -template class ACE_Svc_Handler<ACE_SOCK_STREAM, ACE_NULL_SYNCH>; -<font color=blue>#elif defined</font> (<font color=purple>ACE_HAS_TEMPLATE_INSTANTIATION_PRAGMA</font>) -<font color=blue>#pragma</font> <font color=purple>instantiate</font> ACE_Acceptor <Client_Handler, ACE_SOCK_ACCEPTOR> -<font color=blue>#pragma</font> <font color=purple>instantiate</font> ACE_Svc_Handler<ACE_SOCK_STREAM, ACE_NULL_SYNCH> -<font color=blue>#endif</font> <font color=red>/* ACE_HAS_EXPLICIT_TEMPLATE_INSTANTIATION */</font> -</PRE> -<P><HR WIDTH="100%"> -<CENTER>[<A HREF="../online-tutorials.html">Tutorial Index</A>] [<A HREF="page03.html">Continue This Tutorial</A>]</CENTER> |