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diff --git a/docs/tutorials/015/page13.html b/docs/tutorials/015/page13.html deleted file mode 100644 index 967948e3d16..00000000000 --- a/docs/tutorials/015/page13.html +++ /dev/null @@ -1,170 +0,0 @@ -<HTML> -<HEAD> - <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> - <META NAME="Author" CONTENT="James CE Johnson"> - <TITLE>ACE Tutorial 015</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 015</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>Building a protocol stream</FONT></B></CENTER> - -<P> -<HR WIDTH="100%"> -The Protocol_Task implementation takes care of the open(), close(), -put() and svc() methods so that derivatives can concentrate on the -send() and recv() methods. After a while you find that most -ACE_Task<> derivatives look very similar in the four basic methods and -only need one or two additional to do any real work. -<HR> -<PRE> - -<font color=red>// $Id$</font> - -<font color=blue>#include</font> "<font color=green>Protocol_Task.h</font>" - -<font color=red>// Construct the object and remember the thread count.</font> -<font color=#008888>Protocol_Task::Protocol_Task</font>( int _thr_count ) - : desired_thr_count_(_thr_count) -{ -} - -<font color=#008888>Protocol_Task::~Protocol_Task</font>(void) -{ -} - -<font color=red>// Activate the object if necessary.</font> -int <font color=#008888>Protocol_Task::open</font>(void *arg) -{ - ACE_UNUSED_ARG(arg); - - if( desired_thr_count_ ) - { - return this->activate(THR_NEW_LWP, desired_thr_count_); - } - - return(0); -} - -<font color=red>/* When we're being closed by the ACE_Stream and we've got threads to - worry about then we drop a hangup message onto the message queue so - that svc() will go away. Except for the call to is_active(), this - is lifted directly from Tutorial 14. -*/</font> -int <font color=#008888>Protocol_Task::close</font>(u_long flags) -{ - if (flags == 1 && is_active() ) - { - ACE_Message_Block *hangupBlock = new ACE_Message_Block(); - - hangupBlock->msg_type(<font color=#008888>ACE_Message_Block::MB_HANGUP</font>); - - if (this->putq(hangupBlock->duplicate()) == -1) { - ACE_ERROR_RETURN ((LM_ERROR, "<font color=green>%p\n</font>", "<font color=green><font color=#008888>Task::close</font>() putq</font>"), -1); - } - - hangupBlock->release(); - - return this->wait(); - } - - return 0; -} - -<font color=red>/* The put() method has to make a decision. If we've got threads then - put the unit of work onto the message queue for svc() to deal - with. If not then process() it directly. -*/</font> -int <font color=#008888>Protocol_Task::put</font>(ACE_Message_Block *message,ACE_Time_Value *timeout) -{ - if( is_active() ) - { - return this->putq(message,timeout); - } - - return this->process(message,timeout); -} - -<font color=red>/* svc() is about what you would expect. This is again lifted - directly from Tutorial 14 but with a call to process() for handling - the logic instead of doing the work right here. - */</font> -int <font color=#008888>Protocol_Task::svc</font>(void) -{ - ACE_Message_Block * message; - - while (1) - { - <font color=red>// Get a message</font> - if ( this->getq(message, 0) == -1) { - ACE_ERROR_RETURN ((LM_ERROR, "<font color=green>%p\n</font>", "<font color=green><font color=#008888>Protocol_Task::svc</font>() getq</font>"), -1); - } - - ACE_DEBUG ((LM_DEBUG, "<font color=green>(%P|%t) <font color=#008888>Protocol_Task::svc</font>() got message\n</font>")); - - <font color=red>// Check for hangup</font> - if (message->msg_type() == <font color=#008888>ACE_Message_Block::MB_HANGUP</font>) { - - ACE_DEBUG ((LM_DEBUG, "<font color=green>(%P|%t) <font color=#008888>Protocol_Task::svc</font>() -- HANGUP block received\n</font>")); - - <font color=red>// Hangup our thread-pool peers (if any)</font> - if (this->putq(message->duplicate()) == -1) { - ACE_ERROR_RETURN ((LM_ERROR, "<font color=green>%p\n</font>", "<font color=green><font color=#008888>Protocol_Task::svc</font>() putq</font>"), -1); - } - - <font color=red>// Leave svc()</font> - break; - } - - <font color=red>// Do some work on the data.</font> - if( this->process(message->duplicate(),0) == -1 ) - { - break; - } - - <font color=red>// Give up the message block before we go get another.</font> - message->release(); - } - - <font color=red>// Give up the message block that caused us to exit the</font> - <font color=red>// while(1) loop.</font> - message->release(); - - return(0); -} - -<font color=red>/* There's nothing really magic about process(). We just decide if - we're moving data upstream or downstream and invoke the appropriate - virtual function to handle it. -*/</font> -int <font color=#008888>Protocol_Task::process</font>(ACE_Message_Block * message, ACE_Time_Value *timeout) -{ - if( this->is_writer() ) - { - return this->send(message,timeout); - } - - return this->recv(message,timeout); -} - -<font color=red>/* We must insist that derivatives provide a meaningful overload for - these methods. It's fairly common for ACE object methods to return - an error when an overload is expected but the method cannot be - safely made pure virtual. - */</font> - -int <font color=#008888>Protocol_Task::send</font>(ACE_Message_Block *message, - ACE_Time_Value *timeout) -{ - return -1; -} - -int <font color=#008888>Protocol_Task::recv</font>(ACE_Message_Block * message, - ACE_Time_Value *timeout) -{ - return -1; -} -</PRE> -<P><HR WIDTH="100%"> -<CENTER>[<A HREF="../online-tutorials.html">Tutorial Index</A>] [<A HREF="page14.html">Continue This Tutorial</A>]</CENTER> |