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diff --git a/docs/tutorials/012/page05.html b/docs/tutorials/012/page05.html deleted file mode 100644 index dba97f08c41..00000000000 --- a/docs/tutorials/012/page05.html +++ /dev/null @@ -1,232 +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 012</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 012</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>Passing classes through ACE_Message_Queue</FONT></B></CENTER> - - -<P> -<HR WIDTH="100%"> -<P> -The Task is the only object we've not been through yet. I'll go ahead -and show both the header and cpp on this one page since the header -isn't very large. -<P> -<HR WIDTH="100%"> -<HR width=50%><P><center>task.h</center><HR width=50%> -<PRE> - -<font color=red>// $Id$</font> - -<font color=blue>#ifndef</font> <font color=purple>TASK_H</font> -<font color=blue>#define</font> <font color=purple>TASK_H</font> - -<font color=blue>#include</font> "<A HREF="../../../ace/Task.h">ace/Task.h</A>" - -<font color=blue>#if !defined</font> (<font color=purple>ACE_LACKS_PRAGMA_ONCE</font>) -<font color=blue># pragma</font> <font color=purple>once</font> -<font color=blue>#endif</font> <font color=red>/* ACE_LACKS_PRAGMA_ONCE */</font> - -<font color=red>/* - This is our basic thread-pool Task. We have a choice of pool size - on the open() and the usual svc() and close() methods. - - A new addition is the ACE_Barrier object. This will allow the - synchronization of our svc() methods so that they all start at the - "<font color=green>same</font>" time. The normal case may allow one thread to start working - earlier than others. There's no real harm in it but you can get - better "<font color=green>work by thread</font>" statistics if they start out together. -*/</font> -class Task : public ACE_Task < ACE_MT_SYNCH > -{ -public: - - typedef ACE_Task < ACE_MT_SYNCH > inherited; - - Task (void); - ~Task (void); - - <font color=red>/* - I really wanted this to be called open() but that was already - claimed by the Task framework. start() will kick off our thread - pool for us. - */</font> - int start (int threads = 1); - - virtual int svc (void); - - virtual int close (u_long flags = 0); - -protected: - ACE_Barrier * barrier_; -}; - -<font color=blue>#endif</font> -</PRE> -<HR width=50%><P><center>task.cpp</center><HR width=50%> -<PRE> - -<font color=red>// $Id$</font> - -<font color=blue>#include</font> "<font color=green>task.h</font>" -<font color=blue>#include</font> "<font color=green>block.h</font>" -<font color=blue>#include</font> "<font color=green>work.h</font>" - -<font color=red>/* - Boring default constructor. Be sure our barrier_ is initialized in - case we get destructed before opened. -*/</font> -<font color=#008888>Task::Task</font> (void) -: barrier_ (0) -{ - ACE_DEBUG ((LM_DEBUG, "<font color=green>(%P|%t) Task ctor 0x%x\n</font>", (void *) this)); -} - -<font color=red>/* - You'll see in the svc() method that when we get a shutdown request, - we always putq() it back into our message queue. The last thread in - the pool will do this also and result in there always being one - shutdown request left in the queue when we get here. Just to be - polite, we'll go ahead and get that message and release it. - - We also delete the barrier_ object we used to synch the svc() - methods. -*/</font> -<font color=#008888>Task::~Task</font> (void) -{ - ACE_DEBUG ((LM_DEBUG, "<font color=green>(%P|%t) Task dtor 0x%x\n</font>", (void *) this)); - - ACE_Message_Block *message; - this->getq (message); - message->release (); - - delete barrier_; -} - -<font color=red>/* - The ACE_Barrier needs to know how many threads it will be working - for. For that reason, we have to put off it's construction until we - get here. We then pass the thread count through to our base class' - activate(). -*/</font> -int <font color=#008888>Task::start</font> (int threads) -{ - barrier_ = new ACE_Barrier (threads); - return this->activate (THR_NEW_LWP, threads); -} - -<font color=red>/* - We don't really do anything here but I wanted to provide a message - in the output. -*/</font> -int <font color=#008888>Task::close</font> (u_long flags) -{ - ACE_DEBUG ((LM_DEBUG, "<font color=green>(%P|%t) Task close 0x%x\n</font>", (void *) this)); - return <font color=#008888>inherited::close</font> (flags); -} - -<font color=red>/* - Now the svc() method where everything interesting happens. -*/</font> -int <font color=#008888>Task::svc</font> (void) -{ - <font color=red>/* - All of the threads will block here until the last thread - arrives. They will all then be free to begin doing work. - */</font> - this->barrier_->wait (); - - ACE_DEBUG ((LM_DEBUG, "<font color=green>(%P|%t) Task 0x%x starts in thread %u\n</font>", (void *) this, <font color=#008888>ACE_Thread::self</font> ())); - - <font color=red>// Where we getq() the message</font> - ACE_Message_Block *message; - <font color=red>// What we really put into the queue is a Message_Block, so we'll</font> - <font color=red>// cast the 'message' to 'message_block' after getting it. I'm</font> - <font color=red>// going through some extra steps here just to be explicit</font> - Message_Block * message_block; - <font color=red>// The baseclass of the work object we put into the queue. Notice</font> - <font color=red>// that we can use this and not bother with the Work object at all.</font> - Unit_Of_Work * unit_of_work; - - while (1) - { - <font color=red>// Get the message...</font> - if (this->getq (message) == -1) - { - ACE_ERROR_RETURN ((LM_ERROR, "<font color=green>%p\n</font>", "<font color=green>getq</font>"), -1); - } - - <font color=red>// Is it a shutdown request?</font> - if (message->msg_type () == <font color=#008888>ACE_Message_Block::MB_HANGUP</font>) - { - <font color=red>// Send the shutdown to all of our pool peers</font> - this->putq (message); - break; - } - - <font color=red>// Cast the pointer to our specialized Message_Block. We could</font> - <font color=red>// have done this at the getq() call but I wanted to be explicit</font> - <font color=red>// about what we're doing here</font> - message_block = (Message_Block*)message; - - <font color=red>/* - Since we left alone the ACE_Data_Block used by the - Message_Block we have chosen to use it to send arbitrary data - as well. - */</font> - const char *cp = message_block->rd_ptr (); - <font color=red>// Don't forget to skip the NULL we inserted</font> - message_block->rd_ptr (strlen (cp) + 1); - - <font color=red>/* - Get the Unit_Of_Work pointer out of our specialized - Message_Block. Since the methods of interest are virtual, we - don't have to know what kind of work we're to do. - */</font> - unit_of_work = message_block->data(); - - <font color=red>/* - Invoke a couple of method calls on the object we constructed. - */</font> - unit_of_work->who_am_i (); - unit_of_work->what_am_i (); - - ACE_DEBUG ((LM_DEBUG, "<font color=green>(%P|%t) Block 0x%x contains (%s)\n</font>", (void *) message, cp)); - - <font color=red>/* - Pretend that the work takes a little time to process. This - prevents one thread from getting all of the action. In a real - system you wouldn't need to do this since the work really - would take time to complete. - */</font> - <font color=#008888>ACE_OS::sleep</font> (ACE_Time_Value (0, 5000)); - - <font color=red>/* - Release the message block and allow the unit of work to also go - away. - */</font> - message->release (); - } - - return (0); -} -</PRE> -<HR WIDTH="100%"> -<P> -Like main() this is actually simpler than the previous tutorial. It's -much cleaner to carry around a pointer to the object we're working -with than to try copying data. -<P> -The only complication is the new ACE_Barrier. It's a pretty simple -object that makes it easy for you to synch threads in this way. You -could do some fancy tricks with mutexes, counters & semaphores but why -bother when the Barrier already exists. -<P> -<P><HR WIDTH="100%"> -<CENTER>[<A HREF="../online-tutorials.html">Tutorial Index</A>] [<A HREF="page06.html">Continue This Tutorial</A>]</CENTER> |