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// $Id: Semaphores_1.cpp 91673 2010-09-08 18:49:47Z johnnyw $
#include "ace/SV_Shared_Memory.h"
#include "ace/SV_Semaphore_Simple.h"
#include "ace/SV_Semaphore_Complex.h"
#include "ace/Shared_Memory_Pool.h"
#include "ace/Malloc_T.h"
#include "ace/OS_NS_unistd.h"
#if defined (ACE_HAS_SYSV_IPC) && !defined(ACE_LACKS_SYSV_SHMEM)
// Shared memory allocator (note that this chews up the
// ACE_DEFAULT_SEM_KEY).
static ACE_Malloc<ACE_SHARED_MEMORY_POOL, ACE_SV_Semaphore_Simple> alloc;
const int SEM_KEY = ACE_DEFAULT_SEM_KEY + 1;
static int
parent (char *shm)
{
char *s = shm;
ACE_SV_Semaphore_Complex sem (SEM_KEY, ACE_SV_Semaphore_Complex::ACE_CREATE, 0, 2);
for (char c = 'a'; c <= 'z'; c++)
*s++ = c;
*s = '\0';
if (sem.release (0) == -1)
ACE_ERROR ((LM_ERROR, "%p", "parent sem.release(0)"));
else if (sem.acquire (1) == -1)
ACE_ERROR ((LM_ERROR, "%p", "parent sem.acquire(1)"));
if (alloc.remove () == -1)
ACE_ERROR ((LM_ERROR, "%p\n", "alloc.remove"));
if (sem.remove () == -1)
ACE_ERROR ((LM_ERROR, "%p\n", "sem.remove"));
return 0;
}
static int
child (char *shm)
{
ACE_SV_Semaphore_Complex sem (SEM_KEY, ACE_SV_Semaphore_Complex::ACE_CREATE, 0, 2);
while (sem.tryacquire (0) == -1)
if (errno == EAGAIN)
ACE_DEBUG ((LM_DEBUG, "spinning in client!\n"));
else
ACE_ERROR_RETURN ((LM_ERROR, "client mutex.tryacquire(0)"), 1);
for (char *s = (char *) shm; *s != '\0'; s++)
ACE_DEBUG ((LM_DEBUG, "%c", *s));
ACE_DEBUG ((LM_DEBUG, "\n"));
if (sem.release (1) < 0)
ACE_ERROR ((LM_ERROR, "client sem.release(1)"));
return 0;
}
int
ACE_TMAIN (int, ACE_TCHAR *[])
{
char *shm = (char *) alloc.malloc (27);
switch (ACE_OS::fork ())
{
case -1:
ACE_ERROR_RETURN ((LM_ERROR, "fork failed\n"), -1);
/* NOTREACHED */
case 0:
// Child.
return child (shm);
default:
return parent (shm);
}
}
#else
int ACE_TMAIN (int, ACE_TCHAR *[])
{
ACE_ERROR ((LM_ERROR,
"SYSV IPC, or SYSV SHMEM is not supported on this platform\n"));
return 0;
}
#endif /* ACE_HAS_SYSV_IPC */
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