added: a deadlock counter to Synchro class

now we can use Lock() more than one in the same thread
       and next Unlock() will recognize it
       sample:
       Lock(); // first lock -- resources locked
       Lock(); // second lock -- skipped (counter incremented)
       ...
       Unlock(); // first unlock -- skipped (because counter greater than zero)
       Unlock(); // second unlock -- actually unlocking


git-svn-id: svn://ttmath.org/publicrep/winix/trunk@830 e52654a7-88a9-db11-a3e9-0013d4bc506e

core/synchro.cpp

@@ -2,31 +2,53 @@
  * This file is a part of Winix
  * and is not publicly distributed
  * 
- * Copyright (c) 2010, Tomasz Sowa
+ * Copyright (c) 2010-2012, Tomasz Sowa
  * All rights reserved.
  * 
  */
- 
-#include "synchro.h"
 
+#include <errno.h>
+#include "synchro.h"
 
 
 Synchro::Synchro() : mutex(PTHREAD_MUTEX_INITIALIZER)
 {
 	was_stop_signal = false;
+	ref = 0;
 }
 
 
 
 bool Synchro::Lock()
 {
-	return pthread_mutex_lock(&mutex) == 0;
+	int res = pthread_mutex_lock(&mutex);
+
+	if( res == EDEADLK )
+	{
+		// Lock() method in this thread was called before
+		ref += 1;
+		return true;
+	}
+	else
+	{
+		ref = 0;
+	}
+
+return res == 0;
 }
 
 
+
 void Synchro::Unlock()
 {
-	pthread_mutex_unlock(&mutex);
+	if( ref > 0 )
+	{
+		ref -= 1;
+	}
+	else
+	{
+		pthread_mutex_unlock(&mutex);
+	}
 }