ACE/examples/APG/Processes/Process_Mutex.cpp

   1 #include "ace/OS_NS_unistd.h"
   2 #include "ace/Log_Msg.h"
   3 #include "ace/Process.h"
   4 #include "ace/Process_Mutex.h"
   5
   6 // Listing 1 code/ch10
   7 class GResourceUser
   8 {
   9 public:
  10   GResourceUser (ACE_Process_Mutex &mutex) : gmutex_(mutex)
  11   {
  12     ACE_TRACE ("GResourceUser::GResourceUser");
  13   }
  14
  15   void run ()
  16   {
  17     ACE_TRACE ("GResourceUser::run");
  18
  19     int count = 0;
  20     while (count++ < 10)
  21       {
  22         int result = this->gmutex_.acquire ();
  23         ACE_TEST_ASSERT (result == 0);
  24
  25         ACE_DEBUG ((LM_DEBUG,
  26                     ACE_TEXT ("(%P| %t) has the mutex\n")));
  27
  28         // Access Global resource
  29         ACE_OS::sleep (1);
  30
  31         result = this->gmutex_.release ();
  32         ACE_TEST_ASSERT (result == 0);
  33         ACE_OS::sleep (1);     // Give other process a chance.
  34       }
  35   }
  36
  37 private:
  38   ACE_Process_Mutex &gmutex_;
  39 };
  40 // Listing 1
  41
  42 // Listing 0 code/ch10
  43 int ACE_TMAIN (int argc, ACE_TCHAR *argv[])
  44 {
  45   if (argc > 1)      // Run as the child.
  46     {
  47       // Create or get the global mutex.
  48       ACE_Process_Mutex mutex ("GlobalMutex");
  49
  50       GResourceUser acquirer (mutex);
  51       acquirer.run ();
  52     }
  53   else              // Run as the parent.
  54     {
  55       ACE_Process_Options options;
  56       options.command_line (ACE_TEXT ("%s a"), argv[0]);
  57       ACE_Process processa, processb;
  58
  59       pid_t pida = processa.spawn (options);
  60       pid_t pidb = processb.spawn (options);
  61
  62       ACE_DEBUG ((LM_DEBUG,
  63                   ACE_TEXT ("Spawned processes; pids %d:%d\n"),
  64                   pida, pidb));
  65
  66       if (processa.wait() == -1)
  67         ACE_ERROR_RETURN ((LM_ERROR, ACE_TEXT ("%p\n"),
  68                            ACE_TEXT ("processa wait")), -1);
  69
  70       if (processb.wait() == -1)
  71         ACE_ERROR_RETURN ((LM_ERROR, ACE_TEXT ("%p\n"),
  72                            ACE_TEXT ("processb wait")), -1);
  73     }
  74
  75   return 0;
  76 }
  77 // Listing 0