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-rw-r--r--ACE/examples/Threads/auto_event.cpp118
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diff --git a/ACE/examples/Threads/auto_event.cpp b/ACE/examples/Threads/auto_event.cpp
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+// $Id$
+
+// This test shows the use of an ACE_Auto_Event as a signaling
+// mechanism. Two threads are created (one a reader, the other a
+// writer). The reader waits till the writer has completed
+// calculations. Upon waking up the reader prints the data calculated
+// by the writer. The writer thread calculates the value and signals
+// the reader when the calculation completes.
+
+#include "ace/OS_NS_unistd.h"
+#include "ace/OS_main.h"
+#include "ace/Service_Config.h"
+#include "ace/Auto_Event.h"
+#include "ace/Singleton.h"
+#include "ace/Thread_Manager.h"
+
+#if defined (ACE_HAS_THREADS)
+// Shared event between reader and writer. The ACE_Thread_Mutex is
+// necessary to make sure that only one ACE_Auto_Event is created.
+// The default constructor for ACE_Auto_Event sets it initially into
+// the non-signaled state.
+
+typedef ACE_Singleton <ACE_Auto_Event, ACE_Thread_Mutex> EVENT;
+
+// work time for writer
+static int work_time;
+
+// Reader thread.
+static void *
+reader (void *arg)
+{
+ // Shared data via a reference.
+ int& data = *(int *) arg;
+
+ // Wait for writer to complete.
+
+ ACE_DEBUG ((LM_DEBUG, "(%t) reader: waiting......\n"));
+
+ if (EVENT::instance ()->wait () == -1)
+ {
+ ACE_ERROR ((LM_ERROR, "thread wait failed"));
+ ACE_OS::exit (0);
+ }
+
+ // Read shared data.
+ ACE_DEBUG ((LM_DEBUG, "(%t) reader: value of data is: %d\n", data));
+
+ return 0;
+}
+
+// Writer thread.
+static void *
+writer (void *arg)
+{
+ int& data = *(int *) arg;
+
+ // Calculate (work).
+ ACE_DEBUG ((LM_DEBUG, "(%t) writer: working for %d secs\n", work_time));
+ ACE_OS::sleep (work_time);
+
+ // Write shared data.
+ data = 42;
+
+ // Wake up reader.
+ ACE_DEBUG ((LM_DEBUG, "(%t) writer: calculation complete, waking reader\n"));
+
+ if (EVENT::instance ()->signal () == -1)
+ {
+ ACE_ERROR ((LM_ERROR, "thread signal failed"));
+ ACE_OS::exit (0);
+ }
+
+ return 0;
+}
+
+int
+ACE_TMAIN (int argc, ACE_TCHAR **argv)
+{
+ // Shared data: set by writer, read by reader.
+ int data;
+
+ // Work time for writer.
+ work_time = argc == 2 ? ACE_OS::atoi (argv[1]) : 5;
+
+ // threads manager
+ ACE_Thread_Manager& tm = *ACE_Thread_Manager::instance ();
+
+ // Create reader thread.
+ if (tm.spawn ((ACE_THR_FUNC) reader, (void *) &data) == -1)
+ ACE_ERROR_RETURN ((LM_ERROR, "thread create for reader failed"), -1);
+
+ // Create writer thread.
+ if (tm.spawn ((ACE_THR_FUNC) writer, (void *) &data) == -1)
+ ACE_ERROR_RETURN ((LM_ERROR, "thread create for writer failed"), -1);
+
+ // Wait for both.
+ if (tm.wait () == -1)
+ ACE_ERROR_RETURN ((LM_ERROR, "thread wait failed"), -1);
+ else
+ ACE_DEBUG ((LM_ERROR, "graceful exit\n"));
+
+ return 0;
+}
+
+#if defined (ACE_HAS_EXPLICIT_STATIC_TEMPLATE_MEMBER_INSTANTIATION)
+template ACE_Singleton<ACE_Auto_Event, ACE_Thread_Mutex> *
+ ACE_Singleton<ACE_Auto_Event, ACE_Thread_Mutex>::singleton_;
+#endif /* ACE_HAS_EXPLICIT_STATIC_TEMPLATE_MEMBER_INSTANTIATION */
+
+
+#else
+int
+ACE_TMAIN (int, ACE_TCHAR *[])
+{
+ ACE_ERROR ((LM_ERROR, "threads not supported on this platform\n"));
+ return 0;
+}
+#endif /* ACE_HAS_THREADS */