1 files changed, 118 insertions, 0 deletions
diff --git a/ACE/examples/APG/Threads/Condition_Variables.cpp b/ACE/examples/APG/Threads/Condition_Variables.cpp
new file mode 100644
index 00000000000..ccb29895032
--- /dev/null
+++ b/ACE/examples/APG/Threads/Condition_Variables.cpp
@@ -0,0 +1,118 @@
+// $Id$
+
+#include "ace/config-lite.h"
+#if defined (ACE_HAS_THREADS)
+
+#include "ace/Task.h"
+#include "ace/Synch.h"
+
+// Listing 1 code/ch12
+class HA_Device_Repository
+{
+public:
+  HA_Device_Repository() : owner_(0)
+  { }
+
+  int is_free (void)
+    { return (this->owner_ == 0); }
+
+  int is_owner (ACE_Task_Base* tb)
+    { return (this->owner_ == tb); }
+
+  ACE_Task_Base *get_owner (void)
+    { return this->owner_; }
+
+  void set_owner (ACE_Task_Base *owner)
+    { this->owner_ = owner; }
+
+  int update_device (int device_id);
+
+private:
+  ACE_Task_Base * owner_;
+};
+// Listing 1
+
+class HA_CommandHandler : public ACE_Task_Base
+{
+public:
+  enum {NUM_USES = 10};
+
+  HA_CommandHandler (HA_Device_Repository& rep,
+                     ACE_Condition<ACE_Thread_Mutex> &wait,
+                     ACE_Thread_Mutex& mutex)
+    : rep_(rep), waitCond_(wait), mutex_(mutex)
+  { }
+
+  virtual int svc (void);
+
+private:
+  HA_Device_Repository &rep_;
+  ACE_Condition<ACE_Thread_Mutex> &waitCond_;
+  ACE_Thread_Mutex &mutex_;
+};
+// Listing 2 code/ch12
+int
+HA_CommandHandler::svc (void)
+{
+  ACE_DEBUG ((LM_DEBUG,
+              ACE_TEXT ("(%t) Handler Thread running\n")));
+
+  for (int i = 0; i < NUM_USES; i++)
+    {
+      this->mutex_.acquire ();
+      while (!this->rep_.is_free ())
+        this->waitCond_.wait ();
+      this->rep_.set_owner (this);
+      this->mutex_.release ();
+
+      this->rep_.update_device (i);
+
+      ACE_ASSERT (this->rep_.is_owner (this));
+      this->rep_.set_owner (0);
+
+      this->waitCond_.signal ();
+    }
+
+  return 0;
+}
+// Listing 2
+int
+HA_Device_Repository::update_device (int device_id)
+{
+  ACE_DEBUG ((LM_DEBUG, ACE_TEXT ("(%t) Updating device %d\n"),
+              device_id));
+
+  ACE_OS::sleep (1);
+  return 0;
+}
+// Listing 3 code/ch12
+int ACE_TMAIN (int, ACE_TCHAR *[])
+{
+  HA_Device_Repository rep;
+  ACE_Thread_Mutex rep_mutex;
+  ACE_Condition<ACE_Thread_Mutex> wait (rep_mutex);
+
+  HA_CommandHandler handler1 (rep, wait, rep_mutex);
+  HA_CommandHandler handler2 (rep, wait, rep_mutex);
+
+  handler1.activate ();
+  handler2.activate ();
+
+  handler1.wait ();
+  handler2.wait ();
+
+  return 0;
+}
+// Listing 3
+
+#else
+#include "ace/OS_main.h"
+#include "ace/OS_NS_stdio.h"
+
+int ACE_TMAIN (int, ACE_TCHAR *[])
+{
+  ACE_OS::puts (ACE_TEXT ("This example requires threads."));
+  return 0;
+}
+
+#endif /* ACE_HAS_THREADS */