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diff --git a/docs/tutorials/015/page11.html b/docs/tutorials/015/page11.html deleted file mode 100644 index 0ae929e8f7d..00000000000 --- a/docs/tutorials/015/page11.html +++ /dev/null @@ -1,195 +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%"> -And now the implementation of the Protocol_Stream. There are more -lines of code here than we've seen so far but it still isn't -complicated. The basic idea is to construct the ACE_Stream with our -set of protocol objects that will manipulate the data. Our primary -concern in this file is to get everything in the correct order! -<HR> -<PRE> - -<font color=red>// $Id$</font> - -<font color=blue>#include</font> "<font color=green>Protocol_Stream.h</font>" -<font color=blue>#include</font> "<font color=green>Protocol_Task.h</font>" - -<font color=blue>#include</font> "<font color=green>Xmit.h</font>" -<font color=blue>#include</font> "<font color=green>Recv.h</font>" - -<font color=blue>#include</font> "<font color=green>Compressor.h</font>" -<font color=blue>#include</font> "<font color=green>Crypt.h</font>" - -<font color=blue>#include</font> "<font color=green>ace/Stream_Modules.h</font>" - -<font color=red>/* You can choose at compile time to include/exclude the protocol - pieces. -*/</font> -<font color=blue>#define</font> <font color=purple>ENABLE_COMPRESSION</font> -<font color=blue>#define</font> <font color=purple>ENABLE_ENCRYPTION</font> - -<font color=red>// The usual typedefs to make things easier to type.</font> -typedef ACE_Module<ACE_MT_SYNCH> Module; -typedef ACE_Thru_Task<ACE_MT_SYNCH> Thru_Task; - -<font color=red>/* Do-nothing constructor and destructor - */</font> - -<font color=#008888>Protocol_Stream::Protocol_Stream</font>( void ) -{ - ; -} - -<font color=#008888>Protocol_Stream::~Protocol_Stream</font>( void ) -{ - ; -} - -<font color=red>/* Even opening the stream is rather simple. The important thing to - rememer is that the modules you push onto the stream first will be - at the tail (eg -- most downstream) end of things when you're - done. - */</font> -int <font color=#008888>Protocol_Stream::open</font>( ACE_SOCK_Stream & _peer, Protocol_Task * _reader ) -{ - <font color=red>// Initialize our peer() to read/write the socket we're given</font> - peer_.set_handle( _peer.get_handle() ); - - <font color=red>// Construct (and remember) the Recv object so that we can</font> - <font color=red>// read from the peer().</font> - recv_ = new Recv( peer() ); - - <font color=red>// Add the transmit and receive tasks to the head of the</font> - <font color=red>// stream. As we add more modules these will get pushed</font> - <font color=red>// downstream and end up nearest the tail by the time we're</font> - <font color=red>// done.</font> - if( stream().push( new Module( "<font color=green>Xmit/Recv</font>", new Xmit( peer() ), recv_ ) ) == -1 ) - { - ACE_ERROR_RETURN ((LM_ERROR, "<font color=green>%p\n</font>", "<font color=green>stream().push( xmit/recv )</font>"), -1); - } - - <font color=red>// Add any other protocol tasks to the stream. Each one is</font> - <font color=red>// added at the head. The net result is that Xmit/Recv are at </font> - <font color=red>// the tail.</font> - if( this->open() == -1 ) - { - return(-1); - } - - <font color=red>// If a reader task was provided then push that in as the</font> - <font color=red>// upstream side of the next-to-head module. Any data read</font> - <font color=red>// from the peer() will be sent through here last. Server</font> - <font color=red>// applications will typically use this task to do the actual</font> - <font color=red>// processing of data.</font> - <font color=red>// Note the use of Thru_Task. Since a module must always have </font> - <font color=red>// a pair of tasks we use this on the writter side as a no-op.</font> - if( _reader ) - { - if( stream().push( new Module( "<font color=green>Reader</font>", new Thru_Task(), _reader ) ) == -1 ) - { - ACE_ERROR_RETURN ((LM_ERROR, "<font color=green>%p\n</font>", "<font color=green>stream().push( reader )</font>"), -1); - } - } - - return(0); -} - -<font color=red>/* Add the necessary protocol objects to the stream. The way we're - pushing things on we will encrypt the data before compressing it. -*/</font> -int <font color=#008888>Protocol_Stream::open</font>(void) -{ -<font color=blue>#if defined</font>(<font color=purple>ENABLE_COMPRESSION</font>) - if( stream().push( new Module( "<font color=green>compress</font>", new Compressor(), new Compressor() ) ) == -1 ) - { - ACE_ERROR_RETURN ((LM_ERROR, "<font color=green>%p\n</font>", "<font color=green>stream().push( comprssor )</font>"), -1); - } -<font color=blue>#endif</font> <font color=red>// ENABLE_COMPRESSION</font> - -<font color=blue>#if defined</font>(<font color=purple>ENABLE_ENCRYPTION</font>) - if( stream().push( new Module( "<font color=green>crypt</font>", new Crypt(), new Crypt() ) ) == -1 ) - { - ACE_ERROR_RETURN ((LM_ERROR, "<font color=green>%p\n</font>", "<font color=green>stream().push( crypt )</font>"), -1); - } -<font color=blue>#endif</font> <font color=red>// ENABLE_ENCRYPTION</font> - return( 0 ); -} - -<font color=red>// Closing the Protocol_Stream is as simple as closing the ACE_Stream.</font> -int <font color=#008888>Protocol_Stream::close</font>(void) -{ - return stream().close(); -} - -<font color=red>// Simply pass the data directly to the ACE_Stream.</font> -int <font color=#008888>Protocol_Stream::put</font>(ACE_Message_Block * & _message, ACE_Time_Value * _timeout ) -{ - return stream().put(_message,_timeout); -} - -<font color=red>/* Tell the Recv module to read some data from the peer and pass it - upstream. Servers will typically use this method in a - handle_input() method to tell the stream to get a client's request. -*/</font> -int <font color=#008888>Protocol_Stream::get</font>(void) -{ - <font color=red>// If there is no Recv module, we're in big trouble!</font> - if( ! recv_ ) - { - ACE_ERROR_RETURN ((LM_ERROR, "<font color=green>(%P|%t) No Recv object!\n</font>"), -1); - } - - <font color=red>// This tells the Recv module to go to it's peer() and read</font> - <font color=red>// some data. Once read, that data will be pushed upstream.</font> - <font color=red>// If there is a reader object then it will have a chance to</font> - <font color=red>// process the data. If not, the received data will be</font> - <font color=red>// available in the message queue of the stream head's reader</font> - <font color=red>// object (eg -- stream().head()->reader()->msg_queue()) and</font> - <font color=red>// can be read with our other get() method below.</font> - if( recv_->get() == -1 ) - { - ACE_ERROR_RETURN ((LM_ERROR, "<font color=green>(%P|%t) Cannot queue read request\n</font>"), -1); - } - - <font color=red>// For flexibility I've added an error() method to tell us if</font> - <font color=red>// something bad has happened to the Recv object.</font> - if( recv_->error() ) - { - ACE_ERROR_RETURN ((LM_ERROR, "<font color=green>(%P|%t) Recv object error!\n</font>"), -1); - } - - return(0); -} - -<font color=red>/* Take a message block off of the stream head reader's message - queue. If the queue is empty, use get() to read from the peer. - This is most often used by client applications. Servers will - generaly insert a reader that will prevent the data from getting - all the way upstream to the head. -*/</font> -int <font color=#008888>Protocol_Stream::get</font>(ACE_Message_Block * & _response, ACE_Time_Value * _timeout ) -{ - if( stream().head()->reader()->msg_queue()->is_empty() ) - { - if( this->get() == -1 ) - { - ACE_ERROR_RETURN ((LM_ERROR, "<font color=green>(%P|%t) Cannot get data into the stream.\n</font>"), -1); - } - } - - return stream().head()->reader()->getq(_response,_timeout); -} -</PRE> -<P><HR WIDTH="100%"> -<CENTER>[<A HREF="..">Tutorial Index</A>] [<A HREF="page12.html">Continue This Tutorial</A>]</CENTER> |