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diff --git a/docs/tutorials/006/page02.html b/docs/tutorials/006/page02.html deleted file mode 100644 index 29d4c457ff1..00000000000 --- a/docs/tutorials/006/page02.html +++ /dev/null @@ -1,205 +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="James CE Johnson"> - <META NAME="Description" CONTENT="A first step towards using ACE productively"> - <TITLE>ACE Tutorial 006</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 006</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>Creating a thread-per-connection server</FONT></B></CENTER> - - -<P> -<HR WIDTH="100%"> - -<P>Again, we begin with <A HREF="server.cpp">server.cpp.</A> If you -look closely you will see that the only difference between this and the -Tutorial 5 implementation is a single comment. - -<P> -<HR WIDTH="100%"><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">// $Id: server.cpp,v 1.1 1998/08/30 13:38:28 -jcej Exp $</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">/*</FONT> -<BR><FONT FACE="Arial,Helvetica"> We try to keep main() very -simple. One of the ways we do that is to push</FONT> -<BR><FONT FACE="Arial,Helvetica"> much of the complicated stuff -into worker objects. In this case, we only</FONT> -<BR><FONT FACE="Arial,Helvetica"> need to include the acceptor -header in our main source file. We let it</FONT> -<BR><FONT FACE="Arial,Helvetica"> worry about the "real work".</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">#include "client_acceptor.h"</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">/*</FONT> -<BR><FONT FACE="Arial,Helvetica"> As before, we create a simple -signal handler that will set our finished</FONT> -<BR><FONT FACE="Arial,Helvetica"> flag. There are, of -course, more elegant ways to handle program shutdown</FONT> -<BR><FONT FACE="Arial,Helvetica"> requests but that isn't really -our focus right now, so we'll just do the</FONT> -<BR><FONT FACE="Arial,Helvetica"> easiest thing.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">static sig_atomic_t finished = 0;</FONT> -<BR><FONT FACE="Arial,Helvetica">extern "C" void handler (int)</FONT> -<BR><FONT FACE="Arial,Helvetica">{</FONT> -<BR><FONT FACE="Arial,Helvetica"> finished = 1;</FONT> -<BR><FONT FACE="Arial,Helvetica">}</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">/*</FONT> -<BR><FONT FACE="Arial,Helvetica"> A server has to listen for -clients at a known TCP/IP port. The default ACE</FONT> -<BR><FONT FACE="Arial,Helvetica"> port is 10002 (at least on -my system) and that's good enough for what we</FONT> -<BR><FONT FACE="Arial,Helvetica"> want to do here. Obviously, -a more robust application would take a command</FONT> -<BR><FONT FACE="Arial,Helvetica"> line parameter or read from -a configuration file or do some other clever</FONT> -<BR><FONT FACE="Arial,Helvetica"> thing. Just like the -signal handler above, though, that's what we want to</FONT> -<BR><FONT FACE="Arial,Helvetica"> focus on, so we're taking -the easy way out.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">static const u_short PORT = ACE_DEFAULT_SERVER_PORT;</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">/*</FONT> -<BR><FONT FACE="Arial,Helvetica"> Finally, we get to main. -Some C++ compilers will complain loudly if your</FONT> -<BR><FONT FACE="Arial,Helvetica"> function signature doesn't -match the prototype. Even though we're not</FONT> -<BR><FONT FACE="Arial,Helvetica"> going to use the parameters, -we still have to specify them.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">int main (int argc, char *argv[])</FONT> -<BR><FONT FACE="Arial,Helvetica">{</FONT> -<BR><FONT FACE="Arial,Helvetica">/*</FONT> -<BR><FONT FACE="Arial,Helvetica"> In our earlier servers, we -used a global pointer to get to the reactor. I've</FONT> -<BR><FONT FACE="Arial,Helvetica"> never really liked that idea, -so I've moved it into main() this time. When</FONT> -<BR><FONT FACE="Arial,Helvetica"> we get to the Client_Handler -object you'll see how we manage to get a</FONT> -<BR><FONT FACE="Arial,Helvetica"> pointer back to this reactor.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica"> ACE_Reactor reactor;</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> /*</FONT> -<BR><FONT FACE="Arial,Helvetica"> The acceptor -will take care of letting clients connect to us. It will</FONT> -<BR><FONT FACE="Arial,Helvetica"> also arrange -for a Client_Handler to be created for each new client.</FONT> -<BR><FONT FACE="Arial,Helvetica"> Since we're only -going to listen at one TCP/IP port, we only need one</FONT> -<BR><FONT FACE="Arial,Helvetica"> acceptor. -If we wanted, though, we could create several of these and</FONT> -<BR><FONT FACE="Arial,Helvetica"> listen at several -ports. (That's what we would do if we wanted to rewrite</FONT> -<BR><FONT FACE="Arial,Helvetica"> inetd for -instance.)</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica"> Client_Acceptor peer_acceptor;</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> /*</FONT> -<BR><FONT FACE="Arial,Helvetica"> Create an ACE_INET_Addr -that represents our endpoint of a connection. We</FONT> -<BR><FONT FACE="Arial,Helvetica"> then open our -acceptor object with that Addr. Doing so tells the acceptor</FONT> -<BR><FONT FACE="Arial,Helvetica"> where to listen -for connections. Servers generally listen at "well known"</FONT> -<BR><FONT FACE="Arial,Helvetica"> addresses. -If not, there must be some mechanism by which the client is</FONT> -<BR><FONT FACE="Arial,Helvetica"> informed of the -server's address.</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> Note how ACE_ERROR_RETURN -is used if we fail to open the acceptor. This</FONT> -<BR><FONT FACE="Arial,Helvetica"> technique is -used over and over again in our tutorials.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica"> if (peer_acceptor.open (ACE_INET_Addr -(PORT), &reactor) == -1)</FONT> -<BR><FONT FACE="Arial,Helvetica"> ACE_ERROR_RETURN ((LM_ERROR, -"%p\n", "open"), -1);</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> /*</FONT> -<BR><FONT FACE="Arial,Helvetica"> As with Tutorial -5, we know that we're now registered with our reactor</FONT> -<BR><FONT FACE="Arial,Helvetica"> so we don't have -to mess with that step.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> /*</FONT> -<BR><FONT FACE="Arial,Helvetica"> Install our signal -handler. You can actually register signal handlers</FONT> -<BR><FONT FACE="Arial,Helvetica"> with the reactor. -You might do that when the signal handler is</FONT> -<BR><FONT FACE="Arial,Helvetica"> responsible for -performing "real" work. Our simple flag-setter doesn't</FONT> -<BR><FONT FACE="Arial,Helvetica"> justify deriving -from ACE_Event_Handler and providing a callback function</FONT> -<BR><FONT FACE="Arial,Helvetica"> though.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica"> ACE_Sig_Action sa ((ACE_SignalHandler) -handler, SIGINT);</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> /*</FONT> -<BR><FONT FACE="Arial,Helvetica"> Like ACE_ERROR_RETURN, -the ACE_DEBUG macro gets used quite a bit. It's a</FONT> -<BR><FONT FACE="Arial,Helvetica"> handy way to -generate uniform debug output from your program.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica"> ACE_DEBUG ((LM_DEBUG, "(%P|%t) -starting up server daemon\n"));</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> /*</FONT> -<BR><FONT FACE="Arial,Helvetica"> This will loop -"forever" invoking the handle_events() method of our</FONT> -<BR><FONT FACE="Arial,Helvetica"> reactor. handle_events() -watches for activity on any registered handlers</FONT> -<BR><FONT FACE="Arial,Helvetica"> and invokes their -appropriate callbacks when necessary. Callback-driven</FONT> -<BR><FONT FACE="Arial,Helvetica"> programming is -a big thing in ACE, you should get used to it. If the</FONT> -<BR><FONT FACE="Arial,Helvetica"> signal handler -catches something, the finished flag will be set and we'll</FONT> -<BR><FONT FACE="Arial,Helvetica"> exit. Conveniently -enough, handle_events() is also interrupted by signals</FONT> -<BR><FONT FACE="Arial,Helvetica"> and will exit -back to the while() loop. (If you want your event loop to</FONT> -<BR><FONT FACE="Arial,Helvetica"> not be interrupted -by signals, checkout the <i>restart</i> flag on the</FONT> -<BR><FONT FACE="Arial,Helvetica"> open() method -of ACE_Reactor if you're interested.)</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica"> while (!finished)</FONT> -<BR><FONT FACE="Arial,Helvetica"> reactor.handle_events -();</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> ACE_DEBUG ((LM_DEBUG, "(%P|%t) shutting -down server daemon\n"));</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> return 0;</FONT> -<BR><FONT FACE="Arial,Helvetica">}</FONT> - -<P> -<HR WIDTH="100%"> - -<P>Let's move along and see what happend to the Client_Acceptor. - -<P> -<HR WIDTH="100%"> -<CENTER>[<A HREF="..">Tutorial -Index</A>] [<A HREF="page03.html">Continue This Tutorial</A>]</CENTER> - -</BODY> -</HTML> |