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diff --git a/docs/tutorials/007/page05.html b/docs/tutorials/007/page05.html deleted file mode 100644 index a5ad7a8d62e..00000000000 --- a/docs/tutorials/007/page05.html +++ /dev/null @@ -1,294 +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 007</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 007</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>Creating a thread-pool server</FONT></B></CENTER> - - -<P> -<HR WIDTH="100%"> - -<P>As you might expect, <A HREF="client_handler.h">client_handler.h</A> -is next. - -<P> -<HR WIDTH="100%"> -<BR> -<BR><FONT FACE="Arial,Helvetica">// $Id: client_handler.h,v 1.1 1998/08/30 -23:47:14 schmidt Exp $</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">#ifndef CLIENT_HANDLER_H</FONT> -<BR><FONT FACE="Arial,Helvetica">#define CLIENT_HANDLER_H</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">/*</FONT> -<BR><FONT FACE="Arial,Helvetica"> Our client handler must exist -somewhere in the ACE_Event_Handler object</FONT> -<BR><FONT FACE="Arial,Helvetica"> hierarchy. This is -a requirement of the ACE_Reactor because it maintains</FONT> -<BR><FONT FACE="Arial,Helvetica"> ACE_Event_Handler pointers -for each registered event handler. You could</FONT> -<BR><FONT FACE="Arial,Helvetica"> derive our Client_Handler -directly from ACE_Event_Handler but you still have</FONT> -<BR><FONT FACE="Arial,Helvetica"> to have an ACE_SOCK_Stream -for the actually connection. With a direct</FONT> -<BR><FONT FACE="Arial,Helvetica"> derivative of ACE_Event_Handler, -you'll have to contain and maintain an</FONT> -<BR><FONT FACE="Arial,Helvetica"> ACE_SOCK_Stream instance -yourself. With ACE_Svc_Handler (which is a</FONT> -<BR><FONT FACE="Arial,Helvetica"> derivative of ACE_Event_Handler) -some of those details are handled for you.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">#include "ace/Svc_Handler.h"</FONT> -<BR><FONT FACE="Arial,Helvetica">#include "ace/SOCK_Stream.h"</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">class Client_Acceptor;</FONT> -<BR><FONT FACE="Arial,Helvetica">class Thread_Pool;</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">/*</FONT> -<BR><FONT FACE="Arial,Helvetica"> Another feature of ACE_Svc_Handler -is it's ability to present the ACE_Task<></FONT> -<BR><FONT FACE="Arial,Helvetica"> interface as well. -That's what the ACE_NULL_SYNCH parameter below is all</FONT> -<BR><FONT FACE="Arial,Helvetica"> about. That's beyond -our scope here but we'll come back to it in the next</FONT> -<BR><FONT FACE="Arial,Helvetica"> tutorial when we start looking -at concurrency options.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica">class Client_Handler : public ACE_Svc_Handler -< ACE_SOCK_STREAM, ACE_NULL_SYNCH ></FONT> -<BR><FONT FACE="Arial,Helvetica">{</FONT> -<BR><FONT FACE="Arial,Helvetica">public:</FONT> -<BR><FONT FACE="Arial,Helvetica"> typedef ACE_Svc_Handler < ACE_SOCK_STREAM, -ACE_NULL_SYNCH > inherited;</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> // Constructor...</FONT> -<BR><FONT FACE="Arial,Helvetica"> Client_Handler (void);</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> /*</FONT> -<BR><FONT FACE="Arial,Helvetica"> The destroy() -method is our preferred method of destruction. We could</FONT> -<BR><FONT FACE="Arial,Helvetica"> have overloaded -the delete operator but that is neither easy nor</FONT> -<BR><FONT FACE="Arial,Helvetica"> intuitive (at -least to me). Instead, we provide a new method of</FONT> -<BR><FONT FACE="Arial,Helvetica"> destruction and -we make our destructor protected so that only ourselves,</FONT> -<BR><FONT FACE="Arial,Helvetica"> our derivatives -and our friends can delete us. It's a nice</FONT> -<BR><FONT FACE="Arial,Helvetica"> compromise.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica"> void destroy (void);</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> /*</FONT> -<BR><FONT FACE="Arial,Helvetica"> Most ACE objects -have an open() method. That's how you make them ready</FONT> -<BR><FONT FACE="Arial,Helvetica"> to do work. -ACE_Event_Handler has a virtual open() method which allows us</FONT> -<BR><FONT FACE="Arial,Helvetica"> to create this -overrride. ACE_Acceptor<> will invoke this method after</FONT> -<BR><FONT FACE="Arial,Helvetica"> creating a new -Client_Handler when a client connects. Notice that the</FONT> -<BR><FONT FACE="Arial,Helvetica"> parameter to -open() is a void*. It just so happens that the pointer</FONT> -<BR><FONT FACE="Arial,Helvetica"> points to the -acceptor which created us. You would like for the parameter</FONT> -<BR><FONT FACE="Arial,Helvetica"> to be an ACE_Acceptor<>* -but since ACE_Event_Handler is generic, that</FONT> -<BR><FONT FACE="Arial,Helvetica"> would tie it -too closely to the ACE_Acceptor<> set of objects. In our</FONT> -<BR><FONT FACE="Arial,Helvetica"> definition of -open() you'll see how we get around that.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica"> int open (void *_acceptor);</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> /*</FONT> -<BR><FONT FACE="Arial,Helvetica"> When an ACE_Task<> -object falls out of the svc() method, the framework</FONT> -<BR><FONT FACE="Arial,Helvetica"> will call the -close() method. That's where we want to cleanup ourselves</FONT> -<BR><FONT FACE="Arial,Helvetica"> if we're running -in either thread-per-connection or thread-pool mode.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica"> int close(u_long flags = 0);</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> /*</FONT> -<BR><FONT FACE="Arial,Helvetica"> When there is -activity on a registered handler, the handle_input() method</FONT> -<BR><FONT FACE="Arial,Helvetica"> of the handler -will be invoked. If that method returns an error code (eg</FONT> -<BR><FONT FACE="Arial,Helvetica"> -- -1) then the -reactor will invoke handle_close() to allow the object to</FONT> -<BR><FONT FACE="Arial,Helvetica"> clean itself -up. Since an event handler can be registered for more than</FONT> -<BR><FONT FACE="Arial,Helvetica"> one type of callback, -the callback mask is provided to inform</FONT> -<BR><FONT FACE="Arial,Helvetica"> handle_close() -exactly which method failed. That way, you don't have to</FONT> -<BR><FONT FACE="Arial,Helvetica"> maintain state -information between your handle_* method calls. The _handle</FONT> -<BR><FONT FACE="Arial,Helvetica"> parameter is -explained below...</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica"> int handle_close (ACE_HANDLE _handle, -ACE_Reactor_Mask _mask);</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> /*</FONT> -<BR><FONT FACE="Arial,Helvetica"> When we register -with the reactor, we're going to tell it that we want to</FONT> -<BR><FONT FACE="Arial,Helvetica"> be notified of -READ events. When the reactor sees that there is read</FONT> -<BR><FONT FACE="Arial,Helvetica"> activity for -us, our handle_input() will be invoked. The _handleg</FONT> -<BR><FONT FACE="Arial,Helvetica"> provided is the -handle (file descriptor in Unix) of the actual connection</FONT> -<BR><FONT FACE="Arial,Helvetica"> causing the activity. -Since we're derived from ACE_Svc_Handler<> and it</FONT> -<BR><FONT FACE="Arial,Helvetica"> maintains it's -own peer (ACE_SOCK_Stream) object, this is redundant for</FONT> -<BR><FONT FACE="Arial,Helvetica"> us. However, -if we had been derived directly from ACE_Event_Handler, we</FONT> -<BR><FONT FACE="Arial,Helvetica"> may have chosen -not to contain the peer. In that case, the _handleg</FONT> -<BR><FONT FACE="Arial,Helvetica"> would be important -to us for reading the client's data.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica"> int handle_input (ACE_HANDLE _handle);</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">protected:</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> /*</FONT> -<BR><FONT FACE="Arial,Helvetica"> If the Client_Acceptor -which created us has chosen a thread-per-connection</FONT> -<BR><FONT FACE="Arial,Helvetica"> strategy then -our open() method will activate us into a dedicate thread.</FONT> -<BR><FONT FACE="Arial,Helvetica"> The svc() method -will then execute in that thread performing some of the</FONT> -<BR><FONT FACE="Arial,Helvetica"> functions we -used to leave up to the reactor.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica"> int svc(void);</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> /*</FONT> -<BR><FONT FACE="Arial,Helvetica"> This has nothing -at all to do with ACE. I've added this here as a worker</FONT> -<BR><FONT FACE="Arial,Helvetica"> function which -I will call from handle_input(). That allows me to</FONT> -<BR><FONT FACE="Arial,Helvetica"> introduce concurrencly -in later tutorials with a no changes to the worker</FONT> -<BR><FONT FACE="Arial,Helvetica"> function. -You can think of process() as application-level code and</FONT> -<BR><FONT FACE="Arial,Helvetica"> everything elase -as application-framework code.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica"> int process (char *_rdbuf, int -_rdbuf_len);</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> /*</FONT> -<BR><FONT FACE="Arial,Helvetica"> We don't really -do anything in our destructor but we've declared it to be</FONT> -<BR><FONT FACE="Arial,Helvetica"> protected to -prevent casual deletion of this object. As I said above, I</FONT> -<BR><FONT FACE="Arial,Helvetica"> really would -prefer that everyone goes through the destroy() method to get</FONT> -<BR><FONT FACE="Arial,Helvetica"> rid of us.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica"> ~Client_Handler (void);</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> /*</FONT> -<BR><FONT FACE="Arial,Helvetica"> When we -get to the definition of Client_Handler we'll see that there are</FONT> -<BR><FONT FACE="Arial,Helvetica"> -several places where we go back to the Client_Acceptor for information.</FONT> -<BR><FONT FACE="Arial,Helvetica"> -It is generally a good idea to do that through an accesor rather than</FONT> -<BR><FONT FACE="Arial,Helvetica"> -using the member variable directly.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica"> Client_Acceptor * client_acceptor( -void )</FONT> -<BR><FONT FACE="Arial,Helvetica"> -{ return this->client_acceptor_; }</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> /*</FONT> -<BR><FONT FACE="Arial,Helvetica"> And since -you shouldn't access a member variable directly, neither should you</FONT> -<BR><FONT FACE="Arial,Helvetica"> -set (mutate) it. Although it might seem silly to do it this way, -you'll thank</FONT> -<BR><FONT FACE="Arial,Helvetica"> -yourself for it later.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica"> void client_acceptor( Client_Acceptor -* _client_acceptor )</FONT> -<BR><FONT FACE="Arial,Helvetica"> -{ this->client_acceptor_ = _client_acceptor; }</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> /*</FONT> -<BR><FONT FACE="Arial,Helvetica"> The concurrency() -accessor tells us the current concurrency strategy. It actually</FONT> -<BR><FONT FACE="Arial,Helvetica"> -queries the Client_Acceptor for it but by having the accessor in place, -we could</FONT> -<BR><FONT FACE="Arial,Helvetica"> -change our implementation without affecting everything that needs to know.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica"> int concurrency(void);</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> /*</FONT> -<BR><FONT FACE="Arial,Helvetica"> Likewise -for access to the Thread_Pool that we belong to.</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica"> Thread_Pool * thread_pool(void);</FONT> -<BR><FONT FACE="Arial,Helvetica"></FONT> <FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> Client_Acceptor * client_acceptor_;</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> /*</FONT> -<BR><FONT FACE="Arial,Helvetica"> For some -reason I didn't create accessor/mutator methods for this. So much -for</FONT> -<BR><FONT FACE="Arial,Helvetica"> -consistency....</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica"> -This variable is used to remember the thread in which we were created: -the "creator"</FONT> -<BR><FONT FACE="Arial,Helvetica"> -thread in other words. handle_input() needs to know if it is operating -in the</FONT> -<BR><FONT FACE="Arial,Helvetica"> -main reactor thread (which is the one that created us) or if it is operating -in</FONT> -<BR><FONT FACE="Arial,Helvetica"> -one of the thread pool threads. More on this when we get to handle_input().</FONT> -<BR><FONT FACE="Arial,Helvetica"> */</FONT> -<BR><FONT FACE="Arial,Helvetica"> ACE_thread_t -creator_;</FONT> -<BR><FONT FACE="Arial,Helvetica">};</FONT><FONT FACE="Arial,Helvetica"></FONT> - -<P><FONT FACE="Arial,Helvetica">#endif // CLIENT_HANDLER_H</FONT> - -<P> -<HR WIDTH="100%"> - -<P>Still, we're just not seeing a lot of changes due to intruduction of -the thread pool. That's a good thing! You don't want to go turning -your application upside down just because you changed thread models. - -<P> -<HR WIDTH="100%"> -<CENTER>[<A HREF="..">Tutorial -Index</A>] [<A HREF="page06.html">Continue -This Tutorial</A>]</CENTER> - -</BODY> -</HTML> |