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diff --git a/docs/tutorials/010/page05.html b/docs/tutorials/010/page05.html deleted file mode 100644 index 653cb496cb2..00000000000 --- a/docs/tutorials/010/page05.html +++ /dev/null @@ -1,168 +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 010</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 010</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>Passing chunks of data through an ACE_Message_Queue</FONT></B></CENTER> - - -<HR WIDTH="100%"> -<P> - -Our <A HREF="task.cpp">Task</A> object definition: -<P> - -<HR WIDTH="100%"> -<PRE> - -#include "task.h" -#include "block.h" - -/* - Set our housekeeping pointer to NULL and tell the user we exist. - */ -Task::Task (void) -: barrier_ (0) -{ - ACE_DEBUG ((LM_DEBUG, "(%P|%t) Task ctor 0x%x\n", (void *) this)); -} - -/* - Take care of cleanup & tell the user we're going away. -*/ -Task::~Task (void) -{ - ACE_DEBUG ((LM_DEBUG, "(%P|%t) Task dtor 0x%x\n", (void *) this)); - - /* - Get our shutdown notification out of the queue and release it. - */ - ACE_Message_Block * message; - this->getq(message); - message->release(); - - delete barrier_; -} - -/* - Open the object to do work. We create the Barrier object and tell - it how many threads we'll be using. Next, we activate the Task - into the number of requested threads. -*/ -int Task::open (int threads) -{ - barrier_ = new ACE_Barrier (threads); - return this->activate (THR_NEW_LWP, threads); -} - -/* - Tell the user we're closing and invoke the baseclass' close() to - take care of things. -*/ -int Task::close (u_long flags) -{ - ACE_DEBUG ((LM_DEBUG, "(%P|%t) Task close 0x%x\n", (void *) this)); - return inherited::close (flags); -} - -/* - Our svc() method waits for work on the queue and then processes that work. - */ -int Task::svc (void) -{ - /* - This will cause all of the threads to wait on this line until all - have invoked this method. The net result is that no thread in the - Task will get a shot at the queue until all of the threads are active. - There's no real need to do this but it's an easy intro into the use - of ACE_Barrier. - */ - this->barrier_->wait (); - - ACE_DEBUG ((LM_DEBUG, "(%P|%t) Task 0x%x starts in thread %d\n", (void *) this, ACE_Thread::self ())); - - /* - Remember that get() needs a reference to a pointer. To save stack - thrashing we'll go ahead and create a pointer outside of the almost- - infinite loop. - */ - ACE_Message_Block *message; - while (1) - { - /* - Get a message from the queue. - */ - if (this->getq (message) == -1) - { - ACE_ERROR_RETURN ((LM_ERROR, "%p\n", "getq"), -1); - } - - /* - If we got the shutdown request, we need to go away. - */ - if (message->msg_type () == ACE_Message_Block::MB_HANGUP) - { - /* - Forward the request to any peer threads. - */ - this->putq (message); - - /* - Leave the infinite loop so that the thread exits. - */ - break; - } - - /* - The message queue stores char* data. We use rd_ptr() to get to - the beginning of the data. - */ - const char *cp = message->rd_ptr (); - - /* - Move the rd_ptr() past the data we read. This isn't real useful - here since we won't be reading any more from the block but it's - a good habit to get into. - */ - message->rd_ptr( strlen(cp) ); - - /* - Display the block's address and data to the user. - */ - ACE_DEBUG ((LM_DEBUG, "(%P|%t) Block 0x%x contains (%s)\n", (void *) message, cp)); - - /* - Pretend that it takes a while to process the data. - */ - ACE_OS::sleep (ACE_Time_Value (0, 5000)); - - /* - Release the message block. Notice that we never delete a message block. - Blocks are reference counted & the release() method will take care of - the delete when there are no more references to the data. - */ - message->release (); - } - - return (0); -} -</PRE> -<HR WIDTH="100%"> -<P> -This is all pretty straight-forward too. One gottcha we avoided was a memory leak -due to our shutdown message. Notice that svc() enqueues that block without bothering -to see if there are any more threads to dequeue it. Thats why our dtor can call getq() -without worrying about blocking infinitely: it knows the message block will be there. -<P> -<HR WIDTH="100%"> - -<CENTER>[<A HREF="..">Tutorial Index</A>] [<A HREF="page06.html">Continue -This Tutorial</A>]</CENTER> - -</BODY> -</HTML> |