// Mangle SDP to prefer ISAC/16000 over any other audio codec.
private string preferISAC(string sdpDescription)
{
string[] lines = sdpDescription.Split("\n", true);
int mLineIndex = -1;
string isac16kRtpMap = null;
Java.Util.Regex.Pattern isac16kPattern = Java.Util.Regex.Pattern.Compile("^a=rtpmap:(\\d+) ISAC/16000[\r]?$");
for (int i = 0; (i < lines.Length) && (mLineIndex == -1 || isac16kRtpMap == null); ++i)
{
if (lines[i].StartsWith("m=audio "))
{
mLineIndex = i;
continue;
}
Matcher isac16kMatcher = isac16kPattern.Matcher(lines[i]);
if (isac16kMatcher.Matches())
{
isac16kRtpMap = isac16kMatcher.Group(1);
continue;
}
}
if (mLineIndex == -1)
{
Log.Debug(TAG, "No m=audio line, so can't prefer iSAC");
return(sdpDescription);
}
if (isac16kRtpMap == null)
{
Log.Debug(TAG, "No ISAC/16000 line, so can't prefer iSAC");
return(sdpDescription);
}
string[] origMLineParts = lines[mLineIndex].Split(" ", true);
StringBuilder newMLine = new StringBuilder();
int origPartIndex = 0;
// Format is: m=<media> <port> <proto> <fmt> ...
newMLine.Append(origMLineParts[origPartIndex++]).Append(" ");
newMLine.Append(origMLineParts[origPartIndex++]).Append(" ");
newMLine.Append(origMLineParts[origPartIndex++]).Append(" ");
newMLine.Append(isac16kRtpMap).Append(" ");
for (; origPartIndex < origMLineParts.Length; ++origPartIndex)
{
if (!origMLineParts[origPartIndex].Equals(isac16kRtpMap))
{
newMLine.Append(origMLineParts[origPartIndex]).Append(" ");
}
}
lines[mLineIndex] = newMLine.ToString();
StringBuilder newSdpDescription = new StringBuilder();
foreach (string line in lines)
{
newSdpDescription.Append(line).Append("\n");
}
return(newSdpDescription.ToString());
}
// Fetches |url| and fishes the signaling parameters out of the HTML via
// regular expressions.
//
// TODO(fischman): replace this hackery with a dedicated JSON-serving URL in
// apprtc so that this isn't necessary (here and in other future apps that
// want to interop with apprtc).
private AppRTCSignalingParameters getParametersForRoomUrl(string url)
{
Java.Util.Regex.Pattern fullRoomPattern = Java.Util.Regex.Pattern.Compile(".*\n *Sorry, this room is full\\..*");
string roomHtml = drainStream((new URL(url)).OpenConnection().InputStream);
Matcher fullRoomMatcher = fullRoomPattern.Matcher(roomHtml);
if (fullRoomMatcher.Find())
{
throw new IOException("Room is full!");
}
string gaeBaseHref = url.Substring(0, url.IndexOf('?'));
string token = getVarValue(roomHtml, "channelToken", true);
string postMessageUrl = "/message?r=" + getVarValue(roomHtml, "roomKey", true) + "&u=" + getVarValue(roomHtml, "me", true);
bool initiator = getVarValue(roomHtml, "initiator", false).Equals("1");
List <PeerConnection.IceServer> iceServers = outerInstance.iceServersFromPCConfigJSON(getVarValue(roomHtml, "pcConfig", false));
bool isTurnPresent = false;
foreach (PeerConnection.IceServer server in iceServers)
{
if (server.Uri.StartsWith("turn:"))
{
isTurnPresent = true;
break;
}
}
if (!isTurnPresent)
{
iceServers.Add(requestTurnServer(getVarValue(roomHtml, "turnUrl", true)));
}
MediaConstraints pcConstraints = constraintsFromJSON(getVarValue(roomHtml, "pcConstraints", false));
Log.Debug(TAG, "pcConstraints: " + pcConstraints);
MediaConstraints videoConstraints = constraintsFromJSON(getVideoConstraints(getVarValue(roomHtml, "mediaConstraints", false)));
Log.Debug(TAG, "videoConstraints: " + videoConstraints);
return(new AppRTCSignalingParameters(outerInstance, iceServers, gaeBaseHref, token, postMessageUrl, initiator, pcConstraints, videoConstraints));
}
// Scan |roomHtml| for declaration & assignment of |varName| and return its
// value, optionally stripping outside quotes if |stripQuotes| requests it.
private string getVarValue(string roomHtml, string varName, bool stripQuotes)
{
Java.Util.Regex.Pattern pattern = Java.Util.Regex.Pattern.Compile(".*\n *var " + varName + " = ([^\n]*);\n.*");
Matcher matcher = pattern.Matcher(roomHtml);
if (!matcher.Find())
{
throw new IOException("Missing " + varName + " in HTML: " + roomHtml);
}
string varValue = matcher.Group(1);
if (matcher.Find())
{
throw new IOException("Too many " + varName + " in HTML: " + roomHtml);
}
if (stripQuotes)
{
varValue = varValue.Substring(1, varValue.Length - 1 - 1);
}
return(varValue);
}