1 /*
2  * libjingle
3  * Copyright 2011 Google Inc.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions are met:
7  *
8  *  1. Redistributions of source code must retain the above copyright notice,
9  *     this list of conditions and the following disclaimer.
10  *  2. Redistributions in binary form must reproduce the above copyright notice,
11  *     this list of conditions and the following disclaimer in the documentation
12  *     and/or other materials provided with the distribution.
13  *  3. The name of the author may not be used to endorse or promote products
14  *     derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
17  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
18  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
19  * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
20  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
22  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
23  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
24  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
25  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include "talk/media/base/streamparams.h"
29 
30 #include <list>
31 #include <sstream>
32 
33 namespace cricket {
34 namespace {
35 // NOTE: There is no check here for duplicate streams, so check before
36 // adding.
AddStream(std::vector<StreamParams> * streams,const StreamParams & stream)37 void AddStream(std::vector<StreamParams>* streams, const StreamParams& stream) {
38   streams->push_back(stream);
39 }
40 }
41 
42 const char kFecSsrcGroupSemantics[] = "FEC";
43 const char kFidSsrcGroupSemantics[] = "FID";
44 const char kSimSsrcGroupSemantics[] = "SIM";
45 
GetStream(const StreamParamsVec & streams,const StreamSelector & selector,StreamParams * stream_out)46 bool GetStream(const StreamParamsVec& streams,
47                const StreamSelector& selector,
48                StreamParams* stream_out) {
49   const StreamParams* found = GetStream(streams, selector);
50   if (found && stream_out)
51     *stream_out = *found;
52   return found != nullptr;
53 }
54 
GetAudioStream(const StreamSelector & selector,StreamParams * stream)55 bool MediaStreams::GetAudioStream(
56     const StreamSelector& selector, StreamParams* stream) {
57   return GetStream(audio_, selector, stream);
58 }
59 
GetVideoStream(const StreamSelector & selector,StreamParams * stream)60 bool MediaStreams::GetVideoStream(
61     const StreamSelector& selector, StreamParams* stream) {
62   return GetStream(video_, selector, stream);
63 }
64 
GetDataStream(const StreamSelector & selector,StreamParams * stream)65 bool MediaStreams::GetDataStream(
66     const StreamSelector& selector, StreamParams* stream) {
67   return GetStream(data_, selector, stream);
68 }
69 
CopyFrom(const MediaStreams & streams)70 void MediaStreams::CopyFrom(const MediaStreams& streams) {
71   audio_ = streams.audio_;
72   video_ = streams.video_;
73   data_ = streams.data_;
74 }
75 
AddAudioStream(const StreamParams & stream)76 void MediaStreams::AddAudioStream(const StreamParams& stream) {
77   AddStream(&audio_, stream);
78 }
79 
AddVideoStream(const StreamParams & stream)80 void MediaStreams::AddVideoStream(const StreamParams& stream) {
81   AddStream(&video_, stream);
82 }
83 
AddDataStream(const StreamParams & stream)84 void MediaStreams::AddDataStream(const StreamParams& stream) {
85   AddStream(&data_, stream);
86 }
87 
RemoveAudioStream(const StreamSelector & selector)88 bool MediaStreams::RemoveAudioStream(
89     const StreamSelector& selector) {
90   return RemoveStream(&audio_, selector);
91 }
92 
RemoveVideoStream(const StreamSelector & selector)93 bool MediaStreams::RemoveVideoStream(
94     const StreamSelector& selector) {
95   return RemoveStream(&video_, selector);
96 }
97 
RemoveDataStream(const StreamSelector & selector)98 bool MediaStreams::RemoveDataStream(
99     const StreamSelector& selector) {
100   return RemoveStream(&data_, selector);
101 }
102 
SsrcsToString(const std::vector<uint32_t> & ssrcs)103 static std::string SsrcsToString(const std::vector<uint32_t>& ssrcs) {
104   std::ostringstream ost;
105   ost << "ssrcs:[";
106   for (std::vector<uint32_t>::const_iterator it = ssrcs.begin();
107        it != ssrcs.end(); ++it) {
108     if (it != ssrcs.begin()) {
109       ost << ",";
110     }
111     ost << *it;
112   }
113   ost << "]";
114   return ost.str();
115 }
116 
has_semantics(const std::string & semantics_in) const117 bool SsrcGroup::has_semantics(const std::string& semantics_in) const {
118   return (semantics == semantics_in && ssrcs.size() > 0);
119 }
120 
ToString() const121 std::string SsrcGroup::ToString() const {
122   std::ostringstream ost;
123   ost << "{";
124   ost << "semantics:" << semantics << ";";
125   ost << SsrcsToString(ssrcs);
126   ost << "}";
127   return ost.str();
128 }
129 
ToString() const130 std::string StreamParams::ToString() const {
131   std::ostringstream ost;
132   ost << "{";
133   if (!groupid.empty()) {
134     ost << "groupid:" << groupid << ";";
135   }
136   if (!id.empty()) {
137     ost << "id:" << id << ";";
138   }
139   ost << SsrcsToString(ssrcs) << ";";
140   ost << "ssrc_groups:";
141   for (std::vector<SsrcGroup>::const_iterator it = ssrc_groups.begin();
142        it != ssrc_groups.end(); ++it) {
143     if (it != ssrc_groups.begin()) {
144       ost << ",";
145     }
146     ost << it->ToString();
147   }
148   ost << ";";
149   if (!type.empty()) {
150     ost << "type:" << type << ";";
151   }
152   if (!display.empty()) {
153     ost << "display:" << display << ";";
154   }
155   if (!cname.empty()) {
156     ost << "cname:" << cname << ";";
157   }
158   if (!sync_label.empty()) {
159     ost << "sync_label:" << sync_label;
160   }
161   ost << "}";
162   return ost.str();
163 }
GetPrimarySsrcs(std::vector<uint32_t> * ssrcs) const164 void StreamParams::GetPrimarySsrcs(std::vector<uint32_t>* ssrcs) const {
165   const SsrcGroup* sim_group = get_ssrc_group(kSimSsrcGroupSemantics);
166   if (sim_group == NULL) {
167     ssrcs->push_back(first_ssrc());
168   } else {
169     for (size_t i = 0; i < sim_group->ssrcs.size(); ++i) {
170       ssrcs->push_back(sim_group->ssrcs[i]);
171     }
172   }
173 }
174 
GetFidSsrcs(const std::vector<uint32_t> & primary_ssrcs,std::vector<uint32_t> * fid_ssrcs) const175 void StreamParams::GetFidSsrcs(const std::vector<uint32_t>& primary_ssrcs,
176                                std::vector<uint32_t>* fid_ssrcs) const {
177   for (size_t i = 0; i < primary_ssrcs.size(); ++i) {
178     uint32_t fid_ssrc;
179     if (GetFidSsrc(primary_ssrcs[i], &fid_ssrc)) {
180       fid_ssrcs->push_back(fid_ssrc);
181     }
182   }
183 }
184 
AddSecondarySsrc(const std::string & semantics,uint32_t primary_ssrc,uint32_t secondary_ssrc)185 bool StreamParams::AddSecondarySsrc(const std::string& semantics,
186                                     uint32_t primary_ssrc,
187                                     uint32_t secondary_ssrc) {
188   if (!has_ssrc(primary_ssrc)) {
189     return false;
190   }
191 
192   ssrcs.push_back(secondary_ssrc);
193   std::vector<uint32_t> ssrc_vector;
194   ssrc_vector.push_back(primary_ssrc);
195   ssrc_vector.push_back(secondary_ssrc);
196   SsrcGroup ssrc_group = SsrcGroup(semantics, ssrc_vector);
197   ssrc_groups.push_back(ssrc_group);
198   return true;
199 }
200 
GetSecondarySsrc(const std::string & semantics,uint32_t primary_ssrc,uint32_t * secondary_ssrc) const201 bool StreamParams::GetSecondarySsrc(const std::string& semantics,
202                                     uint32_t primary_ssrc,
203                                     uint32_t* secondary_ssrc) const {
204   for (std::vector<SsrcGroup>::const_iterator it = ssrc_groups.begin();
205        it != ssrc_groups.end(); ++it) {
206     if (it->has_semantics(semantics) &&
207           it->ssrcs.size() >= 2 &&
208           it->ssrcs[0] == primary_ssrc) {
209       *secondary_ssrc = it->ssrcs[1];
210       return true;
211     }
212   }
213   return false;
214 }
215 
IsOneSsrcStream(const StreamParams & sp)216 bool IsOneSsrcStream(const StreamParams& sp) {
217   if (sp.ssrcs.size() == 1 && sp.ssrc_groups.empty()) {
218     return true;
219   }
220   if (sp.ssrcs.size() == 2) {
221     const SsrcGroup* fid_group = sp.get_ssrc_group(kFidSsrcGroupSemantics);
222     if (fid_group != NULL) {
223       return (sp.ssrcs == fid_group->ssrcs);
224     }
225   }
226   return false;
227 }
228 
RemoveFirst(std::list<uint32_t> * ssrcs,uint32_t value)229 static void RemoveFirst(std::list<uint32_t>* ssrcs, uint32_t value) {
230   std::list<uint32_t>::iterator it =
231       std::find(ssrcs->begin(), ssrcs->end(), value);
232   if (it != ssrcs->end()) {
233     ssrcs->erase(it);
234   }
235 }
236 
IsSimulcastStream(const StreamParams & sp)237 bool IsSimulcastStream(const StreamParams& sp) {
238   const SsrcGroup* const sg = sp.get_ssrc_group(kSimSsrcGroupSemantics);
239   if (sg == NULL || sg->ssrcs.size() < 2) {
240     return false;
241   }
242   // Start with all StreamParams SSRCs. Remove simulcast SSRCs (from sg) and
243   // RTX SSRCs. If we still have SSRCs left, we don't know what they're for.
244   // Also we remove first-found SSRCs only. So duplicates should lead to errors.
245   std::list<uint32_t> sp_ssrcs(sp.ssrcs.begin(), sp.ssrcs.end());
246   for (size_t i = 0; i < sg->ssrcs.size(); ++i) {
247     RemoveFirst(&sp_ssrcs, sg->ssrcs[i]);
248   }
249   for (size_t i = 0; i < sp.ssrc_groups.size(); ++i) {
250     const SsrcGroup& group = sp.ssrc_groups[i];
251     if (group.semantics.compare(kFidSsrcGroupSemantics) != 0 ||
252         group.ssrcs.size() != 2) {
253       continue;
254     }
255     RemoveFirst(&sp_ssrcs, group.ssrcs[1]);
256   }
257   // If there's SSRCs left that we don't know how to handle, we bail out.
258   return sp_ssrcs.size() == 0;
259 }
260 
261 }  // namespace cricket
262