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diff --git a/docs/tutorials/021/page04.html b/docs/tutorials/021/page04.html deleted file mode 100644 index 2886b87e19e..00000000000 --- a/docs/tutorials/021/page04.html +++ /dev/null @@ -1,111 +0,0 @@ -<!-- $Id$ --> -<HTML> -<HEAD> - <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> - <META NAME="Author" CONTENT="James CE Johnson"> - <TITLE>ACE Tutorial 021</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 021</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>Pooling your memories</FONT></B></CENTER> - -<P> -<HR WIDTH="100%"> - Everything common the server & client is kept here. In - particular, the Constants class where we keep the names & - semaphore keys. - <p> - The Allocator class is just a thin wrapper around - ACE_Malloc<> that moves some of the details out of the - application logic. -<hr> -<PRE> - -<font color=red>// $Id$</font> - -<font color=blue>#ifndef</font> <font color=purple>MPOOL_H</font> -<font color=blue>#define</font> <font color=purple>MPOOL_H</font> - -<font color=red>// Everything else we need is in this one header</font> -<font color=blue>#include</font> "<A HREF="../../../ace/Malloc.h">ace/Malloc.h</A>" - -<font color=blue>#if !defined</font> (<font color=purple>ACE_LACKS_SYSV_SHMEM</font>) - -<font color=red>/* - With this we will abstract away some of the details of the memory - pool. Note that we don't treat this as a singleton because an - application may need more than one pool. Each would have a - different name and be used for different purposes. - */</font> - -class Allocator -{ -public: - <font color=red>// The pool name will be used to create a unique semaphore to</font> - <font color=red>// keep this pool separate from others.</font> - Allocator (const char * _name = "<font color=green>MemoryPool</font>"); - ~Allocator (void); - - typedef ACE_Malloc<ACE_MMAP_MEMORY_POOL, ACE_SV_Semaphore_Simple> pool_t; - - <font color=red>// Provide an accessor to the pool. This will also allocate the</font> - <font color=red>// pool when first invoked.</font> - pool_t &pool (void); - -protected: - - <font color=red>// The name we gave to the pool</font> - char *name_; - - pool_t *pool_; -}; - -<font color=red>/* - The client and server need to agree on a certain set of values. By - placing them in the Constants class we can eliminate a bit of confusion. - */</font> -class Constants -{ -public: - <font color=red>// The semaphore keys are needed for the two semaphores that</font> - <font color=red>// synch access to the shared memory area.</font> - static const int SEM_KEY_1; - static const int SEM_KEY_2; - - <font color=red>// How big the pool will be and what we'll put into it. A real</font> - <font color=red>// app wouldn't need SHMDATA of course.</font> - static const int SHMSZ; - static const char *SHMDATA; - - <font color=red>// The name assigned to the memory pool by the server is needed</font> - <font color=red>// by the client. Without it, the pool cannot be found.</font> - <font color=red>// Likewise, the name the server will bind() to the region of the</font> - <font color=red>// pool must be available to the client.</font> - static const char *PoolName; - static const char *RegionName; -}; - -<font color=blue>#endif</font> <font color=red>/* ACE_LACKS_SYSV_SHMEM */</font> -<font color=blue>#endif</font> <font color=red>/* MPOOL_H */</font> -</PRE> -<HR> - The really hard stuff is done by the ACE_Malloc<> template. This - template takes two parameters.<sup>*</sup> The first is a - memory pool class to use. ACE has several, I've choosen one - that uses a memory-mapped file. The second parameter is a lock - class of some sort. This is needed so that the ACE_Malloc<> can - protect its internal data. Note that you still have to - provide your own mutex around the data you put into the - malloc'd area. - -<P> - * Actually, some implementations may require a different - number of parameters. - That's why ACE uses those funky macros. ACE_MMAP_MEMORY_POOL - for instance turns into ACE_MMAP_Memory_Pool on Linux but may - do other things on your platform. -<P><HR WIDTH="100%"> -<CENTER>[<A HREF="../online-tutorials.html">Tutorial Index</A>] [<A HREF="page05.html">Continue This Tutorial</A>]</CENTER> - |