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diff --git a/dep/src/zthread/posix/ConditionRecursiveLock.h b/dep/src/zthread/posix/ConditionRecursiveLock.h
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+/*
+ * Copyright (c) 2005, Eric Crahen
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is furnished
+ * to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ */
+
+#ifndef __ZTFASTRECURSIVELOCK_H__
+#define __ZTFASTRECURSIVELOCK_H__
+
+#include "zthread/NonCopyable.h"
+#include <pthread.h>
+#include <errno.h>
+#include <assert.h>
+
+namespace ZThread {
+
+/**
+ * @class FastRecursiveLock
+ *
+ * @author Eric Crahen <http://www.code-foo.com>
+ * @date <2003-07-16T23:28:37-0400>
+ * @version 2.2.0
+ *
+ * This is an implementation of a FastRecursiveLock for any vannila
+ * POSIX system. It is based on a condition variable and a mutex; 
+ * because of this it is important to not that its waiting properties
+ * are not the same as other mutex implementations that generally
+ * based on spin locks. Under high contention, this implementation may
+ * be preferable to a spin lock, although refactoring the design of
+ * code that puts a mutex under alot of preasure may be worth investigating.
+ */ 
+class FastRecursiveLock : private NonCopyable {
+
+  //! Serialize state
+  pthread_mutex_t _mtx;
+
+  //! Wait for lock
+  pthread_cond_t _cond;
+
+  //! Owner
+  pthread_t _owner;
+
+  //! Count
+  volatile unsigned int _count;
+
+public:
+
+  inline FastRecursiveLock() : _owner(0), _count(0) {
+    
+    pthread_mutex_init(&_mtx, 0);
+    if(pthread_cond_init(&_cond, 0) != 0) {
+      assert(0);
+    }
+
+  }
+  
+  inline ~FastRecursiveLock() {
+
+    pthread_mutex_destroy(&_mtx);
+    if(pthread_cond_destroy(&_cond) != 0) {
+      assert(0); 
+    }
+    
+  }
+  
+  inline void acquire() {
+    
+    pthread_t self = pthread_self();
+    pthread_mutex_lock(&_mtx);
+
+    // If the caller does not own the lock, wait until there is no owner
+    if(_owner != 0 && !pthread_equal(_owner, self)) {
+
+      int status = 0;
+      do { // ignore signals
+        status = pthread_cond_wait(&_cond, &_mtx);
+      } while(status == EINTR && _owner == 0);
+      
+    }
+    
+    _owner = self;
+    _count++;
+
+    pthread_mutex_unlock(&_mtx);
+ 
+  }
+
+  inline bool tryAcquire(unsigned long timeout=0) {
+
+    pthread_t self = pthread_self();
+    pthread_mutex_lock(&_mtx);
+
+    // If the caller owns the lock, or there is no owner update the count
+    bool success = (_owner == 0 || pthread_equal(_owner, self));
+    if(success) {
+      
+      _owner = self;
+      _count++;
+      
+    }
+
+    pthread_mutex_unlock(&_mtx);
+
+    return success;
+
+  }
+
+  inline void release() {
+    
+    assert(pthread_equal(_owner, pthread_self()));
+
+    pthread_mutex_lock(&_mtx);
+    if(--_count == 0) {
+
+      _owner = 0;
+      pthread_cond_signal(&_cond);
+
+    }
+
+    pthread_mutex_unlock(&_mtx);
+    
+  }
+  
+  
+}; /* FastRecursiveLock */
+
+
+} // namespace ZThread 
+
+#endif