1 /*
2  *  Copyright (c) 2013 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 #ifndef CALL_CALL_H_
11 #define CALL_CALL_H_
12 
13 #include <algorithm>
14 #include <memory>
15 #include <string>
16 #include <vector>
17 
18 #include "api/rtcerror.h"
19 #include "call/audio_receive_stream.h"
20 #include "call/audio_send_stream.h"
21 #include "call/audio_state.h"
22 #include "call/flexfec_receive_stream.h"
23 #include "call/rtp_transport_controller_send_interface.h"
24 #include "call/video_receive_stream.h"
25 #include "call/video_send_stream.h"
26 #include "common_types.h"  // NOLINT(build/include)
27 #include "rtc_base/bitrateallocationstrategy.h"
28 #include "rtc_base/networkroute.h"
29 #include "rtc_base/platform_file.h"
30 #include "rtc_base/socket.h"
31 
32 namespace webrtc {
33 
34 class AudioProcessing;
35 class RtcEventLog;
36 
37 enum class MediaType {
38   ANY,
39   AUDIO,
40   VIDEO,
41   DATA
42 };
43 
44 // Like std::min, but considers non-positive values to be unset.
45 // TODO(zstein): Remove once all callers use rtc::Optional.
46 template <typename T>
MinPositive(T a,T b)47 static T MinPositive(T a, T b) {
48   if (a <= 0) {
49     return b;
50   }
51   if (b <= 0) {
52     return a;
53   }
54   return std::min(a, b);
55 }
56 
57 class PacketReceiver {
58  public:
59   enum DeliveryStatus {
60     DELIVERY_OK,
61     DELIVERY_UNKNOWN_SSRC,
62     DELIVERY_PACKET_ERROR,
63   };
64 
65   virtual DeliveryStatus DeliverPacket(MediaType media_type,
66                                        const uint8_t* packet,
67                                        size_t length,
68                                        const PacketTime& packet_time) = 0;
69 
70  protected:
~PacketReceiver()71   virtual ~PacketReceiver() {}
72 };
73 
74 // A Call instance can contain several send and/or receive streams. All streams
75 // are assumed to have the same remote endpoint and will share bitrate estimates
76 // etc.
77 class Call {
78  public:
79   struct Config {
ConfigConfig80     explicit Config(RtcEventLog* event_log) : event_log(event_log) {
81       RTC_DCHECK(event_log);
82     }
83 
84     static constexpr int kDefaultStartBitrateBps = 300000;
85 
86     // Bitrate config used until valid bitrate estimates are calculated. Also
87     // used to cap total bitrate used. This comes from the remote connection.
88     struct BitrateConfig {
89       int min_bitrate_bps = 0;
90       int start_bitrate_bps = kDefaultStartBitrateBps;
91       int max_bitrate_bps = -1;
92     } bitrate_config;
93 
94     // The local client's bitrate preferences. The actual configuration used
95     // is a combination of this and |bitrate_config|. The combination is
96     // currently more complicated than a simple mask operation (see
97     // SetBitrateConfig and SetBitrateConfigMask). Assumes that 0 <= min <=
98     // start <= max holds for set parameters.
99     struct BitrateConfigMask {
100       rtc::Optional<int> min_bitrate_bps;
101       rtc::Optional<int> start_bitrate_bps;
102       rtc::Optional<int> max_bitrate_bps;
103     };
104 
105     // AudioState which is possibly shared between multiple calls.
106     // TODO(solenberg): Change this to a shared_ptr once we can use C++11.
107     rtc::scoped_refptr<AudioState> audio_state;
108 
109     // Audio Processing Module to be used in this call.
110     // TODO(solenberg): Change this to a shared_ptr once we can use C++11.
111     AudioProcessing* audio_processing = nullptr;
112 
113     // RtcEventLog to use for this call. Required.
114     // Use webrtc::RtcEventLog::CreateNull() for a null implementation.
115     RtcEventLog* event_log = nullptr;
116   };
117 
118   struct Stats {
119     std::string ToString(int64_t time_ms) const;
120 
121     int send_bandwidth_bps = 0;       // Estimated available send bandwidth.
122     int max_padding_bitrate_bps = 0;  // Cumulative configured max padding.
123     int recv_bandwidth_bps = 0;       // Estimated available receive bandwidth.
124     int64_t pacer_delay_ms = 0;
125     int64_t rtt_ms = -1;
126   };
127 
128   static Call* Create(const Call::Config& config);
129 
130   // Allows mocking |transport_send| for testing.
131   static Call* Create(
132       const Call::Config& config,
133       std::unique_ptr<RtpTransportControllerSendInterface> transport_send);
134 
135   virtual AudioSendStream* CreateAudioSendStream(
136       const AudioSendStream::Config& config) = 0;
137   virtual void DestroyAudioSendStream(AudioSendStream* send_stream) = 0;
138 
139   virtual AudioReceiveStream* CreateAudioReceiveStream(
140       const AudioReceiveStream::Config& config) = 0;
141   virtual void DestroyAudioReceiveStream(
142       AudioReceiveStream* receive_stream) = 0;
143 
144   virtual VideoSendStream* CreateVideoSendStream(
145       VideoSendStream::Config config,
146       VideoEncoderConfig encoder_config) = 0;
147   virtual void DestroyVideoSendStream(VideoSendStream* send_stream) = 0;
148 
149   virtual VideoReceiveStream* CreateVideoReceiveStream(
150       VideoReceiveStream::Config configuration) = 0;
151   virtual void DestroyVideoReceiveStream(
152       VideoReceiveStream* receive_stream) = 0;
153 
154   // In order for a created VideoReceiveStream to be aware that it is
155   // protected by a FlexfecReceiveStream, the latter should be created before
156   // the former.
157   virtual FlexfecReceiveStream* CreateFlexfecReceiveStream(
158       const FlexfecReceiveStream::Config& config) = 0;
159   virtual void DestroyFlexfecReceiveStream(
160       FlexfecReceiveStream* receive_stream) = 0;
161 
162   // All received RTP and RTCP packets for the call should be inserted to this
163   // PacketReceiver. The PacketReceiver pointer is valid as long as the
164   // Call instance exists.
165   virtual PacketReceiver* Receiver() = 0;
166 
167   // Returns the call statistics, such as estimated send and receive bandwidth,
168   // pacing delay, etc.
169   virtual Stats GetStats() const = 0;
170 
171   // The greater min and smaller max set by this and SetBitrateConfigMask will
172   // be used. The latest non-negative start value from either call will be used.
173   // Specifying a start bitrate (>0) will reset the current bitrate estimate.
174   // This is due to how the 'x-google-start-bitrate' flag is currently
175   // implemented. Passing -1 leaves the start bitrate unchanged. Behavior is not
176   // guaranteed for other negative values or 0.
177   virtual void SetBitrateConfig(
178       const Config::BitrateConfig& bitrate_config) = 0;
179 
180   // The greater min and smaller max set by this and SetBitrateConfig will be
181   // used. The latest non-negative start value form either call will be used.
182   // Specifying a start bitrate will reset the current bitrate estimate.
183   // Assumes 0 <= min <= start <= max holds for set parameters.
184   virtual void SetBitrateConfigMask(
185       const Config::BitrateConfigMask& bitrate_mask) = 0;
186 
187   virtual void SetBitrateAllocationStrategy(
188       std::unique_ptr<rtc::BitrateAllocationStrategy>
189           bitrate_allocation_strategy) = 0;
190 
191   // TODO(skvlad): When the unbundled case with multiple streams for the same
192   // media type going over different networks is supported, track the state
193   // for each stream separately. Right now it's global per media type.
194   virtual void SignalChannelNetworkState(MediaType media,
195                                          NetworkState state) = 0;
196 
197   virtual void OnTransportOverheadChanged(
198       MediaType media,
199       int transport_overhead_per_packet) = 0;
200 
201   virtual void OnNetworkRouteChanged(
202       const std::string& transport_name,
203       const rtc::NetworkRoute& network_route) = 0;
204 
205   virtual void OnSentPacket(const rtc::SentPacket& sent_packet) = 0;
206 
207   virtual VoiceEngine* voice_engine() = 0;
208 
~Call()209   virtual ~Call() {}
210 };
211 
212 }  // namespace webrtc
213 
214 #endif  // CALL_CALL_H_
215