src/net-limit/limiter.h

   1 /***************************************************************************
   2  *                                                                         *
   3  *   Copyright (C) 2006 David Brodsky                                      *
   4  *                                                                         *
   5  *   This library is free software; you can redistribute it and/or         *
   6  *   modify it under the terms of the GNU Library General Public           *
   7  *   License as published by the Free Software Foundation and appearing    *
   8  *   in the file LICENSE.LGPL included in the packaging of this file.      *
   9  *                                                                         *
  10  *   This library is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU      *
  13  *   Library General Public License for more details.                      *
  14  *                                                                         *
  15  ***************************************************************************/
  16
  17 #ifndef _tairon_net_limit_limiter_h
  18 #define _tairon_net_limit_limiter_h
  19
  20 #include <list>
  21
  22 #include <tairon/core/signals.h>
  23
  24 namespace Tairon
  25 {
  26
  27 namespace Net
  28 {
  29
  30 /** \brief Limiter is used for limiting network bandwidth.
  31  */
  32 class Limiter
  33 {
  34         public:
  35                 /** Constructs a Limiter object.
  36                  *
  37                  * \param r Maximum number of bytes to by transferred per second.
  38                  * \param p Parent of this limiter. Transfer rate of this limiter won't
  39                  * exceed its parent's rate. If no parent is specified then this
  40                  * limiter notices its child about free bandwidth to use. An instance
  41                  * of Tairon::Net::LimitManager has to be created before Limiter can be
  42                  * used.
  43                  */
  44                 Limiter(size_t r, Limiter *p = 0);
  45
  46                 /** Destroys the object.
  47                  */
  48                 ~Limiter();
  49
  50                 /** Returns maximum number of bytes that can be transferred.
  51                  */
  52                 size_t getAllowedSize(size_t max);
  53
  54                 /** Removes a functor from queue of functors waiting for free transfer.
  55                  */
  56                 void removeFromQueue(Tairon::Core::Functor0<void> *f);
  57
  58                 /** Sets number of transferred bytes to zero and calls waiting functors.
  59                  */
  60                 void reset();
  61
  62                 /** Informs this Limiter about transferred data.
  63                  */
  64                 void transferred(size_t s);
  65
  66                 /** Someone wants to be notified when there is a possibility to transfer
  67                  * more data.
  68                  *
  69                  * \param f Functor that will be called when there are data to read.
  70                  */
  71                 void wantMore(Tairon::Core::Functor0<void> *f);
  72
  73         private:
  74                 /** Parent of this limiter.
  75                  */
  76                 Limiter *parent;
  77
  78                 /** Maximum number of bytes to be transferred per second.
  79                  */
  80                 size_t rate;
  81
  82                 /** Number of bytes that can be transferred.
  83                  */
  84                 size_t rest;
  85
  86                 /** List of functors that will be called when a transfer can be done.
  87                  */
  88                 std::list<Tairon::Core::Functor0<void> *> waiting;
  89
  90                 /** Functor for calling wantMore() method.
  91                  */
  92                 Tairon::Core::Functor0<void> *wantMoreFunctor;
  93 };
  94
  95 }; // namespace Net
  96
  97 }; // namespace Tairon
  98
  99 #endif
 100
 101 // vim: ai sw=4 ts=4 noet fdm=marker