Source/Base/Network/Socket/OSGDgramQueue.cpp

   1 /*---------------------------------------------------------------------------*\
   2  *                                OpenSG                                     *
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   5  *             Copyright (C) 2000-2002 by the OpenSG Forum                   *
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  15  * This library is free software; you can redistribute it and/or modify it   *
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  29 /*---------------------------------------------------------------------------*\
  30  *                                Changes                                    *
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  37 \*---------------------------------------------------------------------------*/
  38
  39 #include <cstdlib>
  40 #include <cstdio>
  41
  42 #include <vector>
  43 #include <algorithm>
  44 #include <set>
  45
  46 #include "OSGConfig.h"
  47 #include "OSGBaseThread.h"
  48 #include "OSGThreadManager.h"
  49 #include "OSGSocketSelection.h"
  50 #include "OSGDgramQueue.h"
  51
  52 OSG_USING_NAMESPACE
  53
  54 /** \class OSG::DgramQueue
  55  *  \brief Stream socket connection
  56  *
  57  **/
  58
  59 /*-------------------------------------------------------------------------*/
  60 /*                            constructor destructor                       */
  61
  62 /*! Constructor
  63  *  size must be 2^x
  64  */
  65
  66 DgramQueue::DgramQueue():
  67     _barrier(NULL ),
  68     _queue  (     ),
  69     _waiting(false)
  70 {
  71     char barrierName[256];
  72     sprintf(barrierName,"DgramQueue%p", static_cast<void *>(this));
  73
  74     // create barrier
  75     _barrier = Barrier::get(barrierName, false);
  76 }
  77
  78 /*! Destructor
  79  */
  80 DgramQueue::~DgramQueue()
  81 {
  82     _barrier = NULL;
  83 }
  84
  85 /*-------------------------------------------------------------------------*/
  86 /*                           put / get                                     */
  87
  88 /*! put a dgram to the queue.
  89  */
  90 void DgramQueue::put( Dgram *dgram )
  91 {
  92     _queue.push_back(dgram);
  93     if(_waiting)
  94     {
  95         _waiting = false;
  96         _barrier->enter(2);
  97     }
  98 }
  99
 100 /*! get a dgram from the queue. Block if queue is empty
 101  */
 102 Dgram *DgramQueue::get( Lock *lock )
 103 {
 104     Dgram *result;
 105
 106     if(_queue.empty())
 107     {
 108         _waiting = true;
 109         lock->release();
 110         _barrier->enter(2);
 111         lock->acquire();
 112     }
 113     result = _queue.front();
 114     _queue.pop_front();
 115
 116     return result;
 117 }
 118
 119 /*! wait for a dgram but dont read
 120  */
 121 void DgramQueue::wait( Lock *lock )
 122 {
 123     if(_queue.empty())
 124     {
 125         _waiting = true;
 126         lock->release();
 127         _barrier->enter(2);
 128         lock->acquire();
 129     }
 130 }
 131
 132 /*! true, if reader is waiting
 133  */
 134 bool DgramQueue::waiting(void)
 135 {
 136     return _waiting;
 137 }
 138
 139 bool DgramQueue::empty(void)
 140 {
 141     return _queue.empty();
 142 }