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diff --git a/TAO/tao/Transport_Queueing_Strategies.h b/TAO/tao/Transport_Queueing_Strategies.h
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+// -*- C++ -*-
+
+//=============================================================================
+/**
+ *  @file    Transport_Queueing_Strategies.h
+ *
+ *  $Id$
+ *
+ *  Queueing strategies for the ORB Messaging layer.
+ *
+ *  @author  Irfan Pyarali
+ */
+//=============================================================================
+
+
+#ifndef TAO_TRANSPORT_QUEUEING_STRATEGIES_H
+#define TAO_TRANSPORT_QUEUEING_STRATEGIES_H
+
+#include /**/ "ace/pre.h"
+
+#include /**/ "tao/TAO_Export.h"
+
+#if !defined (ACE_LACKS_PRAGMA_ONCE)
+# pragma once
+#endif /* ACE_LACKS_PRAGMA_ONCE */
+
+#include "tao/orbconf.h"
+#include "tao/Basic_Types.h"
+
+ACE_BEGIN_VERSIONED_NAMESPACE_DECL
+class ACE_Time_Value;
+ACE_END_VERSIONED_NAMESPACE_DECL
+
+TAO_BEGIN_VERSIONED_NAMESPACE_DECL
+
+class TAO_Stub;
+
+namespace TAO
+{
+  struct BufferingConstraint;
+}
+
+namespace TimeBase
+{
+  typedef CORBA::ULongLong TimeT;
+}
+
+namespace TAO
+{
+  /// Define the interface for the Queueing Strategy
+  /**
+   * The low-level I/O components in the ORB use this strategy to
+   * determine when messages must be queued, immediately sent or
+   * flushed.
+   *
+   * The strategy isolates this low-level components from the higher
+   * level strategies used by the application developer.
+   */
+  class Transport_Queueing_Strategy
+  {
+  public:
+    /// Destructor
+    virtual ~Transport_Queueing_Strategy (void);
+
+    /// Return true if a message must be queued
+    virtual bool must_queue (bool queue_empty) const = 0;
+
+    /// Return true if it is time to start
+    /**
+     * @param stub The object used to make the request, this is used to
+     *        obtain the policies currently in effect for the request
+     * @param msg_count The number of messages currently queued
+     * @param total_bytes Number of bytes currently queued
+     * @param set_timer Returns true if a timer should be set to drain the
+     *        queue
+     * @param interval If set_timer returns 1, this parameter contains
+     *        the timer interval
+     * @param must_flush Is set to true if things must be flushed at this
+     *        moment
+     */
+    virtual bool buffering_constraints_reached (
+      TAO_Stub *stub,
+      size_t msg_count,
+      size_t total_bytes,
+      bool &must_flush,
+      const ACE_Time_Value &current_deadline,
+      bool &set_timer,
+      ACE_Time_Value &interval) const = 0;
+  };
+
+  class Default_Transport_Queueing_Strategy : public Transport_Queueing_Strategy
+  {
+  public:
+    virtual bool must_queue (bool queue_empty) const;
+
+    virtual bool buffering_constraints_reached (
+      TAO_Stub *stub,
+      size_t msg_count,
+      size_t total_bytes,
+      bool &must_flush,
+      const ACE_Time_Value &current_deadline,
+      bool &set_timer,
+      ACE_Time_Value &interval) const;
+  };
+
+  /**
+   * This strategy doesn't not queue by default, but when a message is queued
+   * we always flush it to the transport. This is used for oneways with
+   * SYNC_WITH_TRANSPORT, SYNC_WITH_SERVER and SYNC_WITH_TARGET
+   */
+  class Flush_Transport_Queueing_Strategy : public Transport_Queueing_Strategy
+  {
+  public:
+    virtual bool must_queue (bool queue_empty) const;
+
+    virtual bool buffering_constraints_reached (
+      TAO_Stub *stub,
+      size_t msg_count,
+      size_t total_bytes,
+      bool &must_flush,
+      const ACE_Time_Value &current_deadline,
+      bool &set_timer,
+      ACE_Time_Value &interval) const;
+  };
+
+  #if (TAO_HAS_BUFFERING_CONSTRAINT_POLICY == 1)
+
+  class Eager_Transport_Queueing_Strategy : public Transport_Queueing_Strategy
+  {
+  public:
+    virtual bool must_queue (bool queue_empty) const;
+
+    virtual bool buffering_constraints_reached (
+      TAO_Stub *stub,
+      size_t msg_count,
+      size_t total_bytes,
+      bool &must_flush,
+      const ACE_Time_Value &current_deadline,
+      bool &set_timer,
+      ACE_Time_Value &new_deadline) const;
+
+  private:
+    /// Check if the buffering constraint includes any timeouts and
+    /// compute the right timeout interval if needed.
+    /**
+     * @param buffering_constraint The constraints defined by the
+     *        application
+     * @param current_deadline The current deadline
+     * @param set_timer Return true if the timer should be set
+     * @param new_deadline Return the timer interval value
+     *
+     * @return Returns true if the deadline has already expired and
+     *         flushing must commence immediately.  If the function
+     *         returns false then flushing may need to be delayed, use @c
+     *         set_timer and
+     */
+    bool timer_check (const TAO::BufferingConstraint &buffering_constraint,
+                      const ACE_Time_Value &current_deadline,
+                      bool &set_timer,
+                      ACE_Time_Value &new_deadline) const;
+
+    /// Convert from standard CORBA time units to seconds/microseconds.
+    ACE_Time_Value time_conversion (const TimeBase::TimeT &time) const;
+  };
+
+  /// Delay the buffering decision until the transport blocks
+  /**
+   * If the queue is empty the transport will try to send immediately.
+   */
+  class Delayed_Transport_Queueing_Strategy
+    : public Eager_Transport_Queueing_Strategy
+  {
+  public:
+    virtual bool must_queue (bool queue_empty) const;
+  };
+
+  #endif /* TAO_HAS_BUFFERING_CONSTRAINT_POLICY == 1 */
+
+}
+
+TAO_END_VERSIONED_NAMESPACE_DECL
+
+#include /**/ "ace/post.h"
+
+#endif /* TAO_TRANSPORT_QUEUEING_STRATEGY_H */