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diff --git a/docs/tutorials/021/page02.html b/docs/tutorials/021/page02.html deleted file mode 100644 index 8f48d770840..00000000000 --- a/docs/tutorials/021/page02.html +++ /dev/null @@ -1,183 +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%"> - The key components for creating the memory pool are: - <ul> - <li>Create and name the pool - <li>Allocate a chunk (region) of memory from the pool - <li>Name the allocated region - </ul> - The rest of it is just critical sections and data manipulation. -<hr> -<PRE> - -<font color=red>// $Id$</font> - -<font color=red>/* - I've hidden the details in an Allocator class declared in mpool.h - We'll come to that a little later. -*/</font> -<font color=blue>#include</font> "<font color=green>mpool.h</font>" - -<font color=blue>#if defined</font>(<font color=purple>ACE_LACKS_SYSV_SHMEM</font>) -int -main (int, char *[]) -{ - ACE_ERROR_RETURN ((LM_ERROR, - "<font color=green>System V Semaphores not available on this platform.\n</font>"),100); -} -#else <font color=red>// ACE_LACKS_SYSV_SHMEM</font> -int -main (int, char *[]) -{ - <font color=red>/* - Construction of an Allocator will create the memory pool and - provide it with a name. The Constants class is also - declared in mpool.h to keep server and client on the same - page. The name is used to generate a unique semaphore which - prevents simultaneous access to the pools housekeeping - information. (Note that you still have to provide your own - synch mechanisms for the data *you* put in the poo.) - */</font> - Allocator allocator (<font color=#008888>Constants::PoolName</font>); - - <font color=red>/* - The Allocator class provides the pool() member so that you - have access to the actual memory pool. A more robust - implementation would behave more as a bridge class but this - is good enough for what we're doing here. - Once you have a reference to the pool, the malloc() method - can be used to get some bytes. If successful, shm will - point to the data. Otherwise, it will be zero. - */</font> - char *shm = (char *) allocator.pool ().malloc (27); - - ACE_ASSERT (shm != 0); - - <font color=red>/// FYI</font> - ACE_DEBUG ((LM_INFO, - "<font color=green>Shared memory is at 0x%x\n</font>", - shm)); - - <font color=red>/* - Something that we can do with a memory pool is map a name to - a region provided by malloc. By doing this, we can - communicate that name to the client as a rendezvous - location. Again, a member of Constants is used to keep the - client and server coordinated. - */</font> - if (allocator.pool ().bind(<font color=#008888>Constants::RegionName</font>,shm) == -1) - ACE_ERROR_RETURN ((LM_ERROR, - "<font color=green>Cannot bind the name '%s' to the pointer 0x%x\n</font>", - <font color=#008888>Constants::RegionName</font>, - shm), - 100); - - <font color=red>/* - One of the best ways to synch between different processes is - through the use of semaphores. ACE_SV_Semaphore_Complex - hides the gory details and lets us use them rather easily. - - Here, we'll create two semaphores: mutex and synch. mutex - will be used to provide mutually exclusive access to the - shared region for writting/reading. synch will be used to - prevent the server from removing the memory pool before the - client is done with it. - - Both semaphores are created in an initially locked state. - */</font> - - ACE_SV_Semaphore_Complex mutex; - ACE_ASSERT (mutex.open (<font color=#008888>Constants::SEM_KEY_1</font>, - <font color=#008888>ACE_SV_Semaphore_Complex::ACE_CREATE</font>, - 0) != -1); - - ACE_SV_Semaphore_Complex synch; - ACE_ASSERT (synch.open (<font color=#008888>Constants::SEM_KEY_2</font>, - <font color=#008888>ACE_SV_Semaphore_Complex::ACE_CREATE</font>, - 0) != -1); - - <font color=red>/* - We know the mutex is locked because we created it that way. - Take a moment to write some data into the shared region. - */</font> - for (int i = 0; i < <font color=#008888>Constants::SHMSZ</font>; i++) - shm[i] = <font color=#008888>Constants::SHMDATA</font>[i]; - - <font color=red>/* - The client will be blocking on an acquire() of mutex. By - releasing it here, the client can go look at the shared data. - */</font> - if (mutex.release () == -1) - ACE_ERROR ((LM_ERROR, - "<font color=green>(%P) %p</font>", - "<font color=green>server mutex.release</font>")); - <font color=red>/* - Even though we created the synch semaphore in a locked - state, if we attempt to acquire() it, we will block. Our - design requires that the client release() synch when it is - OK for us to remove the shared memory. - */</font> - else if (synch.acquire () == -1) - ACE_ERROR ((LM_ERROR, - "<font color=green>(%P) %p</font>", - "<font color=green>server synch.acquire</font>")); - <font color=red>/* - This will remove all of the memory pool's resources. In the - case where a memory mapped file is used, the physical file - will also be removed. - */</font> - if (allocator.pool ().remove () == -1) - ACE_ERROR ((LM_ERROR, - "<font color=green>(%P) %p\n</font>", - "<font color=green>server allocator.remove</font>")); - <font color=red>/* - We now have to cleanup the semaphores we created. Use the - ipcs command to see that they did, indeed, go away after the - server exits. - */</font> - - if (mutex.remove () == -1) - ACE_ERROR ((LM_ERROR, - "<font color=green>(%P) %p\n</font>", - "<font color=green>server mutex.remove</font>")); - else if (synch.remove () == -1) - ACE_ERROR ((LM_ERROR, - "<font color=green>(%P) %p\n</font>", - "<font color=green>server synch.remove</font>")); - return 0; -} - -<font color=red>/* - This tutorial was created by shamelessly modifying one of the ACE - examples. Someone there had already created the necessary explicit - template instantiations & I don't want them to go to waste... - */</font> -<font color=blue>#if defined</font> (<font color=purple>ACE_HAS_EXPLICIT_TEMPLATE_INSTANTIATION</font>) -template class ACE_Malloc<ACE_MMAP_MEMORY_POOL, ACE_SV_Semaphore_Simple>; -template class ACE_Guard<ACE_SV_Semaphore_Simple>; -template class ACE_Write_Guard<ACE_SV_Semaphore_Simple>; -template class ACE_Read_Guard<ACE_SV_Semaphore_Simple>; -<font color=blue>#elif defined</font> (<font color=purple>ACE_HAS_TEMPLATE_INSTANTIATION_PRAGMA</font>) -<font color=blue>#pragma</font> <font color=purple>instantiate</font> ACE_Malloc<ACE_MMAP_MEMORY_POOL, ACE_SV_Semaphore_Simple> -<font color=blue>#pragma</font> <font color=purple>instantiate</font> ACE_Guard<ACE_SV_Semaphore_Simple> -<font color=blue>#pragma</font> <font color=purple>instantiate</font> ACE_Write_Guard<ACE_SV_Semaphore_Simple> -<font color=blue>#pragma</font> <font color=purple>instantiate</font> ACE_Read_Guard<ACE_SV_Semaphore_Simple> -<font color=blue>#endif</font> <font color=red>/* ACE_HAS_EXPLICIT_TEMPLATE_INSTANTIATION */</font> - -<font color=blue>#endif</font> <font color=red>/* ACE_LACKS_SYSV_SHMEM */</font> -</PRE> -<P><HR WIDTH="100%"> -<CENTER>[<A HREF="../online-tutorials.html">Tutorial Index</A>] [<A HREF="page03.html">Continue This Tutorial</A>]</CENTER> |