Line data    Source code

       1             : /*
       2             :  *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
       3             :  *
       4             :  *  Use of this source code is governed by a BSD-style license
       5             :  *  that can be found in the LICENSE file in the root of the source
       6             :  *  tree. An additional intellectual property rights grant can be found
       7             :  *  in the file PATENTS.  All contributing project authors may
       8             :  *  be found in the AUTHORS file in the root of the source tree.
       9             :  */
      10             : 
      11             : #ifndef WEBRTC_VOICE_ENGINE_CHANNEL_MANAGER_H
      12             : #define WEBRTC_VOICE_ENGINE_CHANNEL_MANAGER_H
      13             : 
      14             : #include <memory>
      15             : #include <vector>
      16             : 
      17             : #include "webrtc/base/constructormagic.h"
      18             : #include "webrtc/base/criticalsection.h"
      19             : #include "webrtc/base/scoped_ref_ptr.h"
      20             : #include "webrtc/system_wrappers/include/atomic32.h"
      21             : #include "webrtc/typedefs.h"
      22             : #include "webrtc/voice_engine/include/voe_base.h"
      23             : 
      24             : namespace webrtc {
      25             : 
      26             : class AudioDecoderFactory;
      27             : 
      28             : namespace voe {
      29             : 
      30             : class Channel;
      31             : 
      32             : // Shared-pointer implementation for keeping track of Channels. The underlying
      33             : // shared instance will be dropped when no more ChannelOwners point to it.
      34             : //
      35             : // One common source of ChannelOwner instances are
      36             : // ChannelManager::CreateChannel() and ChannelManager::GetChannel(...).
      37             : // It has a similar use case to shared_ptr in C++11. Should this move to C++11
      38             : // in the future, this class should be replaced by exactly that.
      39             : //
      40             : // To access the underlying Channel, use .channel().
      41             : // IsValid() implements a convenience method as an alternative for checking
      42             : // whether the underlying pointer is NULL or not.
      43             : //
      44             : // Channel channel_owner = channel_manager.GetChannel(channel_id);
      45             : // if (channel_owner.IsValid())
      46             : //   channel_owner.channel()->...;
      47             : //
      48             : class ChannelOwner {
      49             :  public:
      50             :   explicit ChannelOwner(Channel* channel);
      51             :   ChannelOwner(const ChannelOwner& channel_owner);
      52             : 
      53             :   ~ChannelOwner();
      54             : 
      55             :   ChannelOwner& operator=(const ChannelOwner& other);
      56             : 
      57           0 :   Channel* channel() const { return channel_ref_->channel.get(); }
      58             :   bool IsValid() { return channel_ref_->channel.get() != NULL; }
      59             :   int use_count() const { return channel_ref_->ref_count.Value(); }
      60             :  private:
      61             :   // Shared instance of a Channel. Copying ChannelOwners increase the reference
      62             :   // count and destroying ChannelOwners decrease references. Channels are
      63             :   // deleted when no references to them are held.
      64           0 :   struct ChannelRef {
      65             :     ChannelRef(Channel* channel);
      66             :     const std::unique_ptr<Channel> channel;
      67             :     Atomic32 ref_count;
      68             :   };
      69             : 
      70             :   ChannelRef* channel_ref_;
      71             : };
      72             : 
      73           0 : class ChannelManager {
      74             :  public:
      75             :   ChannelManager(uint32_t instance_id);
      76             : 
      77             :   // Upon construction of an Iterator it will grab a copy of the channel list of
      78             :   // the ChannelManager. The iteration will then occur over this state, not the
      79             :   // current one of the ChannelManager. As the Iterator holds its own references
      80             :   // to the Channels, they will remain valid even if they are removed from the
      81             :   // ChannelManager.
      82           0 :   class Iterator {
      83             :    public:
      84             :     explicit Iterator(ChannelManager* channel_manager);
      85             : 
      86             :     Channel* GetChannel();
      87             :     bool IsValid();
      88             : 
      89             :     void Increment();
      90             : 
      91             :    private:
      92             :     size_t iterator_pos_;
      93             :     std::vector<ChannelOwner> channels_;
      94             : 
      95             :     RTC_DISALLOW_COPY_AND_ASSIGN(Iterator);
      96             :   };
      97             : 
      98             :   // CreateChannel will always return a valid ChannelOwner instance.
      99             :   ChannelOwner CreateChannel(const VoEBase::ChannelConfig& config);
     100             : 
     101             :   // ChannelOwner.channel() will be NULL if channel_id is invalid or no longer
     102             :   // exists. This should be checked with ChannelOwner::IsValid().
     103             :   ChannelOwner GetChannel(int32_t channel_id);
     104             :   void GetAllChannels(std::vector<ChannelOwner>* channels);
     105             : 
     106             :   void DestroyChannel(int32_t channel_id);
     107             :   void DestroyAllChannels();
     108             : 
     109             :   size_t NumOfChannels() const;
     110             : 
     111             :  private:
     112             :   uint32_t instance_id_;
     113             : 
     114             :   Atomic32 last_channel_id_;
     115             : 
     116             :   rtc::CriticalSection lock_;
     117             :   std::vector<ChannelOwner> channels_;
     118             : 
     119             :   RTC_DISALLOW_COPY_AND_ASSIGN(ChannelManager);
     120             : };
     121             : }  // namespace voe
     122             : }  // namespace webrtc
     123             : 
     124             : #endif  // WEBRTC_VOICE_ENGINE_CHANNEL_MANAGER_H