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diff --git a/dep/src/zthread/SemaphoreImpl.h b/dep/src/zthread/SemaphoreImpl.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 __ZTSEMAPHOREIMPL_H__
+#define __ZTSEMAPHOREIMPL_H__
+
+#include "zthread/Guard.h"
+
+#include "Debug.h"
+#include "FastLock.h"
+#include "Scheduling.h"
+
+#include <assert.h>
+
+namespace ZThread {
+
+  class Monitor;
+
+  /**
+   * @class SemaphoreImpl
+   * @author Eric Crahen <http://www.code-foo.com>
+   * @date <2003-07-16T20:03:20-0400>
+   * @version 2.2.11
+   *
+   * The SemaphoreImpl template allows how waiter lists are sorted
+   * to be parameteized
+   */
+  template <typename List> 
+    class SemaphoreImpl {
+
+    //! List of waiting events
+    List _waiters;
+
+    //! Serialize access to this object
+    FastLock _lock;
+
+    //! Current count
+    volatile int _count;
+
+    //! Maximum count if any
+    volatile int _maxCount;
+  
+    //! Flag for bounded or unbounded count
+    volatile bool _checked;
+
+    //! Entry count
+    volatile int _entryCount;
+
+    public:
+   
+ 
+    /**
+     * Create a new SemaphoreImpl. Initialzes one pthreads mutex for 
+     * internal use.
+     *
+     * @exception Initialization_Exception thrown if resources could not be
+     * properly allocated
+     */
+    SemaphoreImpl(int count, unsigned int maxCount, bool checked) 
+      : _count(count), _maxCount(maxCount), _checked(checked), _entryCount(0) { }
+
+
+    ~SemaphoreImpl();
+
+    void acquire();
+  
+    void release();
+
+    bool tryAcquire(unsigned long timeout);
+ 
+    int count();
+
+  }; 
+
+
+  /**
+   * Destroy this SemaphoreImpl and release its resources. 
+   */
+  template <typename List> 
+    SemaphoreImpl<List>::~SemaphoreImpl() {
+
+#ifndef NDEBUG
+
+    if(!_waiters.empty()) { 
+
+      ZTDEBUG("** You are destroying a semaphore which is blocking %d threads. **\n", _waiters.size());
+      assert(0); // Destroyed semaphore while in use
+
+    }
+
+#endif
+
+  }
+
+
+  /**
+   * Get the count for the Semaphore
+   *
+   * @return int
+   */
+  template <typename List> 
+    int SemaphoreImpl<List>::count() {
+
+    Guard<FastLock> g(_lock);
+    return _count;
+  
+  }
+
+  /**
+   * Decrement the count, blocking when that count becomes 0 or less.
+   * 
+   * @exception Interrupted_Exception thrown when the caller status is interrupted
+   * @exception Synchronization_Exception thrown if there is some other error.
+   */
+  template <typename List> 
+    void SemaphoreImpl<List>::acquire() {
+
+    // Get the monitor for the current thread
+    ThreadImpl* self = ThreadImpl::current();
+    Monitor& m = self->getMonitor();
+
+    Monitor::STATE state;
+
+    Guard<FastLock> g1(_lock);
+
+    // Update the count without waiting if possible.
+    if(_count > 0 && _entryCount == 0)
+      _count--;
+
+    // Otherwise, wait() for the lock by placing the waiter in the list
+    else {
+
+      ++_entryCount;
+      _waiters.insert(self);
+
+      m.acquire();
+
+      {
+      
+        Guard<FastLock, UnlockedScope> g2(g1);
+        state = m.wait();
+      
+      }
+
+      m.release();
+        
+      // Remove from waiter list, regarless of weather release() is called or
+      // not. The monitor is sticky, so its possible a state 'stuck' from a
+      // previous operation and will leave the wait() w/o release() having
+      // been called.
+      typename List::iterator i = std::find(_waiters.begin(), _waiters.end(), self);
+      if(i != _waiters.end())
+        _waiters.erase(i);
+    
+      --_entryCount;
+
+      switch(state) {
+        // If awoke due to a notify(), update the count
+        case Monitor::SIGNALED:
+            
+          _count--;           
+          break;
+           
+        case Monitor::INTERRUPTED:
+          throw Interrupted_Exception();
+            
+        default:
+          throw Synchronization_Exception();
+      } 
+    
+    }
+
+  }
+
+  /**
+   * Decrement the count, blocking when it that count is 0 or less. If the timeout
+   * expires before the count is raise above 0, the thread will stop blocking 
+   * and return.
+   * 
+   * @exception Interrupted_Exception thrown when the caller status is interrupted
+   * @exception Synchronization_Exception thrown if there is some other error.
+   */
+  template <typename List> 
+    bool SemaphoreImpl<List>::tryAcquire(unsigned long timeout) {
+ 
+    // Get the monitor for the current thread
+    ThreadImpl* self = ThreadImpl::current();
+    Monitor& m = self->getMonitor();
+
+    Guard<FastLock> g1(_lock);
+
+    // Update the count without waiting if possible.
+    if(_count > 0 && _entryCount == 0)
+      _count--;
+
+    // Otherwise, wait() for the lock by placing the waiter in the list
+    else {
+    
+      ++_entryCount;
+      _waiters.push_back(self);
+
+      Monitor::STATE state = Monitor::TIMEDOUT;
+
+      // Don't bother waiting if the timeout is 0
+      if(timeout) {
+        
+        m.acquire();
+
+        {
+        
+          Guard<FastLock, UnlockedScope> g2(g1);
+          state = m.wait(timeout);
+        
+        }
+
+        m.release();
+        
+      }
+        
+      // Remove from waiter list, regarless of weather release() is called or
+      // not. The monitor is sticky, so its possible a state 'stuck' from a
+      // previous operation and will leave the wait() w/o release() having
+      // been called.
+      typename List::iterator i = std::find(_waiters.begin(), _waiters.end(), self);
+      if(i != _waiters.end())
+        _waiters.erase(i);
+    
+      --_entryCount;
+
+      switch(state) {
+        // If awoke due to a notify(), update the count
+        case Monitor::SIGNALED:
+            
+          _count--;           
+          break;
+           
+        case Monitor::INTERRUPTED:
+          throw Interrupted_Exception();
+            
+        case Monitor::TIMEDOUT:
+          return false;
+
+        default:
+          throw Synchronization_Exception();
+      } 
+    
+    }
+
+    return true;
+
+  }
+
+  /**
+   * Increment the count and release a waiter if there are any. If the semaphore
+   * is checked, then an exception will be raised if the maximum count is about to
+   * be exceeded. 
+   *
+   * @exception InvalidOp_Exception thrown if the maximum count is exceeded while
+   * the checked flag is set.
+   */
+  template <typename List> 
+    void SemaphoreImpl<List>::release()  {
+
+    Guard<FastLock> g1(_lock);
+
+    // Make sure the operation is valid
+    if(_checked && _count == _maxCount) 
+      throw InvalidOp_Exception();
+
+    // Increment the count
+    _count++;
+
+    // Try to find a waiter with a backoff & retry scheme
+    for(;;) {
+    
+      // Go through the list, attempt to notify() a waiter.
+      for(typename List::iterator i = _waiters.begin(); i != _waiters.end();) {
+
+        // Try the monitor lock, if it cant be locked skip to the next waiter
+        ThreadImpl* impl = *i;
+        Monitor& m = impl->getMonitor();
+
+        if(m.tryAcquire()) {
+        
+          // Notify the monitor & remove from the waiter list so time isn't
+          // wasted checking it again.
+          i = _waiters.erase(i);
+        
+          // If notify() is not sucessful, it is because the wait() has already 
+          // been ended (killed/interrupted/notify'd)
+          bool woke = m.notify();
+        
+          m.release();
+        
+          // Once notify() succeeds, return
+          if(woke) 
+            return;
+        
+        } else ++i;
+      
+      }
+    
+      if(_waiters.empty())
+        return;
+    
+      { // Backoff and try again
+      
+        Guard<FastLock, UnlockedScope> g2(g1);
+        ThreadImpl::yield();
+
+      }
+
+    }
+  
+  }
+
+  class FifoSemaphoreImpl : public SemaphoreImpl<fifo_list> { 
+  public:
+
+    FifoSemaphoreImpl(int count, unsigned int maxCount, bool checked) 
+      /* throw(Synchronization_Exception) */
+      : SemaphoreImpl<fifo_list>(count, maxCount, checked) { }
+
+  };
+
+
+} // namespace ZThread
+
+#endif //  __ZTSEMAPHOREIMPL_H__