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diff --git a/docs/tutorials/015/page19.html b/docs/tutorials/015/page19.html deleted file mode 100644 index 2b62ec0bdb3..00000000000 --- a/docs/tutorials/015/page19.html +++ /dev/null @@ -1,116 +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%"> -Here we implement the details of our compression. By having both -compression and decompression in one object it's easier to keep track -of implementation details. Splitting Xmit/Recv like I did will make -things more difficult if something has to change in their interaction. -<HR> -<PRE> - -<font color=red>// $Id$</font> - -<font color=blue>#include</font> "<font color=green>Compressor.h</font>" -<font color=blue>#include</font> "<A HREF="../../../ace/SOCK_Stream.h">ace/SOCK_Stream.h</A>" - -<font color=#008888>Compressor::Compressor</font>( void ) - : Protocol_Task() -{ - ; -} - -<font color=#008888>Compressor::~Compressor</font>(void) -{ - ; -} - -<font color=red>/* This is where you insert your compression code. Most compressors - want to work on a block of data instead of a byte-stream. - Fortunately the message block has a block that can be compressed. - Take a look at libz for a quick way to add compression to your - apps - */</font> -int <font color=#008888>Compressor::send</font>(ACE_Message_Block *message, ACE_Time_Value *timeout) -{ - ACE_DEBUG ((LM_INFO, "<font color=green>(%P|%t) <font color=#008888>Compressor::send</font>() compressing (%s)\n</font>", message->rd_ptr() )); - - <font color=red>// Create a block to hold the compressed data. I belive libz</font> - <font color=red>// recommends a buffer about 10-20% larger than the source.</font> - <font color=red>// Other libraries/algorithms may have their own quirks.</font> - ACE_Message_Block * compressed = new ACE_Message_Block( message->size() ); - - <font color=red>// Perform a bogus compression algorithm. 'CD' just tells me</font> - <font color=red>// that this is compressed data and when we "<font color=green>decompress</font>" we'll </font> - <font color=red>// look for this signature to validate the data received.</font> - <font color=#008888>ACE_OS::sprintf</font>( compressed->wr_ptr(), "<font color=green>CD:%s</font>", message->rd_ptr() ); - compressed->wr_ptr( strlen(compressed->wr_ptr())+1 ); - - <font color=red>// Send the compressed data down the stream to the next module</font> - this->put_next( compressed ); - - <font color=red>// We're done here.</font> - message->release(); - - return( 0 ); -} - -<font color=red>/* And here's the decompression side. We've written Xmit/Recv so that - we're guaranteed to get an entire block of compressed data. If - we'd used recv() in the Recv object then we might have gotten a - partial block and that may not decompress very nicely. - */</font> -int <font color=#008888>Compressor::recv</font>(ACE_Message_Block *message, ACE_Time_Value *timeout) -{ - ACE_DEBUG ((LM_INFO, "<font color=green>(%P|%t) <font color=#008888>Compress::recv</font>() decompressing (%s)\n</font>", message->rd_ptr() )); - - <font color=red>// Room for the decompressed data. In the real world you</font> - <font color=red>// would probably want to send the original (uncompressed)</font> - <font color=red>// data size in the message. You can predict the maximum</font> - <font color=red>// possible decompression size but it's cheap and easy just to </font> - <font color=red>// send that along. Look again at how I do exacly that</font> - <font color=red>// between Xmit and Recv.</font> - ACE_Message_Block * decompressed = new ACE_Message_Block( message->size() ); - - <font color=red>// Check for our signature. Even when you use a real</font> - <font color=red>// compression algorithm you may want to include your own</font> - <font color=red>// signature so that you can verify the block. It pays to be</font> - <font color=red>// paranoid!</font> - if( <font color=#008888>ACE_OS::strncmp</font>( message->rd_ptr(), "<font color=green>CD:</font>", 3 ) ) - { - ACE_DEBUG ((LM_INFO, "<font color=green>(%P|%t) Improperly encompressed data.\n</font>" )); - message->release(); - return(-1); - } - - <font color=red>// Skip past the signature before going any further.</font> - message->rd_ptr( 3 ); - - <font color=red>// Perform a bogus decompression algorithm. This is where you </font> - <font color=red>// would feed to libz or your favorite decompressor. (It's</font> - <font color=red>// costly but you could invoke popen() on gzip!)</font> - <font color=#008888>ACE_OS::sprintf</font>( decompressed->wr_ptr(), "<font color=green>%s</font>", message->rd_ptr() ); - decompressed->wr_ptr( strlen(decompressed->wr_ptr())+1 ); - - <font color=red>// Recv the decompressed data down the stream to the next module</font> - this->put_next( decompressed ); - - <font color=red>// We're done here.</font> - message->release(); - - return( 0 ); -} - -</PRE> -<P><HR WIDTH="100%"> -<CENTER>[<A HREF="../online-tutorials.html">Tutorial Index</A>] [<A HREF="page20.html">Continue This Tutorial</A>]</CENTER> |