ACE/examples/APG/ThreadSafety/Barrier.cpp

   1 #include "ace/config-lite.h"
   2 #if defined (ACE_HAS_THREADS)
   3
   4 #include "ace/OS_NS_stdlib.h"
   5 #include "ace/OS_NS_time.h"
   6 #include "ace/Task.h"
   7 #include "ace/Synch.h"
   8
   9 // Listing 2 code/ch14
  10 class HA_CommandHandler : public ACE_Task<ACE_MT_SYNCH>
  11 {
  12 public:
  13   enum { N_THREADS = 5 };
  14
  15   HA_CommandHandler (ACE_Barrier& startup_barrier,
  16                      ACE_Barrier &shutdown_barrier)
  17     : startup_barrier_(startup_barrier),
  18       shutdown_barrier_(shutdown_barrier)
  19     { }
  20
  21   void initialize_handler ();
  22   int handle_command_requests ();
  23
  24   int svc ()
  25   {
  26     initialize_handler ();
  27     startup_barrier_.wait ();
  28     ACE_DEBUG ((LM_DEBUG, ACE_TEXT ("(%t: %D) Started\n")));
  29
  30     while (handle_command_requests () > 0)
  31       ;
  32
  33     shutdown_barrier_.wait ();
  34     ACE_DEBUG ((LM_DEBUG, ACE_TEXT ("(%t: %D) Ended\n")));
  35
  36     return 0;
  37   }
  38
  39 private:
  40   ACE_Barrier& startup_barrier_;
  41   ACE_Barrier& shutdown_barrier_;
  42 };
  43 // Listing 2
  44
  45 void
  46 HA_CommandHandler::initialize_handler ()
  47 {
  48   ACE_Time_Value tv (0, ACE_OS::rand () * 100);
  49   timespec_t t = (timespec_t)tv;
  50   ACE_OS::nanosleep (&t);
  51 }
  52
  53 int
  54 HA_CommandHandler::handle_command_requests ()
  55 {
  56   ACE_Time_Value tv (0, ACE_OS::rand () * 100);
  57   timespec_t t = (timespec_t)tv;
  58
  59   // Simulate work.
  60   ACE_OS::nanosleep (&t);
  61
  62   return -1;
  63 }
  64
  65 // Listing 1 code/ch14
  66 int ACE_TMAIN (int, ACE_TCHAR *[])
  67 {
  68   ACE_Barrier startup_barrier (HA_CommandHandler::N_THREADS);
  69   ACE_Barrier shutdown_barrier (HA_CommandHandler::N_THREADS);
  70
  71   HA_CommandHandler handler (startup_barrier, shutdown_barrier);
  72   handler.activate (THR_NEW_LWP | THR_JOINABLE,
  73                     HA_CommandHandler::N_THREADS);
  74   handler.wait ();
  75   return 0;
  76 }
  77 // Listing 1
  78
  79 #else
  80 #include "ace/OS_main.h"
  81 #include "ace/OS_NS_stdio.h"
  82
  83 int ACE_TMAIN (int, ACE_TCHAR *[])
  84 {
  85   ACE_OS::puts (ACE_TEXT ("This example requires threads."));
  86   return 0;
  87 }
  88
  89 #endif /* ACE_HAS_THREADS */