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// $Id$
// ============================================================================
//
// = LIBRARY
// tests
//
// = FILENAME
// Shared_Memory_MM_Test.cpp
//
// = DESCRIPTION
// This is a simple test of <ACE_Shared_Memory_MM>. The test
// forks two processes or spawns two threads (depending upon the
// platform) and then executes child and parent allowing them to
// exchange data using shared memory. No user input is required as
// far as command line arguments are concerned.
//
// = AUTHOR
// Prashant Jain <pjain@cs.wustl.edu>
// and Douglas C. Schmidt <schmidt@cs.wustl.edu>
//
// ============================================================================
#include "test_config.h"
#include "ace/Shared_Memory_MM.h"
#include "ace/Synch.h"
#include "ace/SV_Semaphore_Simple.h"
#include "ace/Process_Semaphore.h"
#include "ace/Thread_Manager.h"
ACE_RCSID(tests, MM_Shared_Memory_Test, "$Id$")
static const char ACE_ALPHABET[] = "abcdefghijklmnopqrstuvwxyz";
const int SHMSZ = 27;
static ACE_TCHAR *shm_key;
#if defined (ACE_LACKS_FORK)
typedef ACE_Thread_Semaphore SYNCHRONIZER;
#elif defined (ACE_HAS_POSIX_SEM)
class SYNCHRONIZER : public ACE_SV_Semaphore_Simple
{
// = TITLE
// If the platform has native cross-process POSIX semaphores, we
// must *force* this test to use the System V Semaphores in order
// to get the right semantics.
public:
SYNCHRONIZER (int initial_value)
: ACE_SV_Semaphore_Simple ((const char *) 0,
ACE_SV_Semaphore_Simple::ACE_CREATE,
initial_value)
{}
};
#else
typedef ACE_Process_Semaphore SYNCHRONIZER;
#endif /* !defined (ACE_LACKS_FORK) */
// Synchronize the start of the parent and the child.
static SYNCHRONIZER *synchronizer = 0;
static void *
child (void * = 0)
{
int result;
// Wait for the parent to be initialized.
result = synchronizer->acquire ();
ACE_ASSERT (result != -1);
const char *t = ACE_ALPHABET;
ACE_Shared_Memory_MM shm_child;
result = shm_child.open (shm_key);
ACE_ASSERT (result != -1);
char *shm = (char *) shm_child.malloc ();
ACE_ASSERT (shm != 0);
for (char *s = shm; *s != '\0'; s++)
{
ACE_ASSERT (*t == s[0]);
t++;
}
// Indicate to the parent that we're done.
*shm = '*';
return 0;
}
static void *
parent (void * = 0)
{
int result;
ACE_Shared_Memory_MM shm_parent;
result = shm_parent.open (shm_key, SHMSZ);
ACE_ASSERT (result != -1);
char *shm = (char *) shm_parent.malloc ();
ACE_ASSERT (shm != 0);
char *s = shm;
for (const char *c = ACE_ALPHABET; *c != '\0'; c++)
*s++ = *c;
*s = '\0';
// Allow the child to proceed.
result = synchronizer->release ();
ACE_ASSERT (result != -1);
// Perform a "busy wait" until the child sets the character to '*'.
while (*shm != '*')
ACE_DEBUG ((LM_DEBUG,
ACE_TEXT ("(%P) spinning in parent!\n")));
result = shm_parent.remove ();
ACE_ASSERT (result != -1);
ACE_OS::unlink (shm_key);
return 0;
}
static int
spawn (void)
{
// Create the synchronizer before spawning the child process/thread,
// to avoid race condition between the creation in the parent and
// use in the child.
ACE_NEW_RETURN (synchronizer,
SYNCHRONIZER (0), // Locked by default...
-1);
#if !defined (ACE_LACKS_FORK)
switch (ACE_OS::fork (ACE_TEXT ("child")))
{
case -1:
ACE_ERROR_RETURN ((LM_ERROR,
ACE_TEXT ("(%P|%t) %p\n"),
ACE_TEXT ("fork failed")),
1);
/* NOTREACHED */
case 0:
parent ();
// Remove the semaphore.
synchronizer->remove ();
delete synchronizer;
break;
/* NOTREACHED */
default:
child ();
delete synchronizer;
break;
/* NOTREACHED */
}
#elif defined (ACE_HAS_THREADS)
if (ACE_Thread_Manager::instance ()->spawn
(ACE_THR_FUNC (child),
(void *) 0,
THR_NEW_LWP | THR_DETACHED) == -1)
ACE_ERROR_RETURN ((LM_ERROR,
ACE_TEXT ("(%P|%t) %p\n"),
ACE_TEXT ("thread create failed")),
1);
else if (ACE_Thread_Manager::instance ()->spawn
(ACE_THR_FUNC (parent),
(void *) 0,
THR_NEW_LWP | THR_DETACHED) == -1)
ACE_ERROR_RETURN ((LM_ERROR,
ACE_TEXT ("(%P|%t) %p\n"),
ACE_TEXT ("thread create failed")),
1);
ACE_Thread_Manager::instance ()->wait ();
delete synchronizer;
#else
ACE_UNUSED_ARG (synchronizer);
ACE_ERROR_RETURN ((LM_ERROR,
ACE_TEXT ("only one thread may be run in a process on this platform\n")),
1);
#endif /* ACE_HAS_THREADS */
return 0;
}
int
main (int, ACE_TCHAR *[])
{
ACE_START_TEST (ACE_TEXT ("MM_Shared_Memory_Test"));
ACE_TCHAR temp_file[MAXPATHLEN + 1];
// Get the temporary directory,
// The - 24 is for the filename, mm_shared_mem_testXXXXXX
if (ACE::get_temp_dir (temp_file, MAXPATHLEN - 24) == -1)
ACE_ERROR_RETURN ((LM_ERROR, ACE_TEXT ("Temporary path too long\n")), -1);
// Add the filename to the end
ACE_OS_String::strcat (temp_file, ACE_TEXT ("mm_shared_mem_testXXXXXX"));
// Store in the global variable.
shm_key = temp_file;
if (ACE_OS::mktemp (shm_key) == 0
|| (ACE_OS::unlink (shm_key) == -1
&& errno == EPERM))
ACE_ERROR_RETURN ((LM_ERROR,
ACE_TEXT ("(%P|%t) %p\n"),
shm_key),
1);
spawn ();
ACE_END_TEST;
return 0;
}
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