| 'use strict'; |
| |
| // This file depends on `webrtc/RTCPeerConnection-helper.js` |
| // which should be loaded from the main HTML file. |
| |
| var kAbsCaptureTime = |
| 'http://www.webrtc.org/experiments/rtp-hdrext/abs-capture-time'; |
| |
| function addHeaderExtensionToSdp(sdp, uri) { |
| const extmap = new RegExp('a=extmap:(\\d+)'); |
| let sdpLines = sdp.split('\r\n'); |
| |
| // This assumes at most one audio m= section and one video m= section. |
| // If more are present, only the first section of each kind is munged. |
| for (const section of ['audio', 'video']) { |
| let found_section = false; |
| let maxId = undefined; |
| let maxIdLine = undefined; |
| let extmapAllowMixed = false; |
| |
| // find the largest header extension id for section. |
| for (let i = 0; i < sdpLines.length; ++i) { |
| if (!found_section) { |
| if (sdpLines[i].startsWith('m=' + section)) { |
| found_section = true; |
| } |
| continue; |
| } else { |
| if (sdpLines[i].startsWith('m=')) { |
| // end of section |
| break; |
| } |
| } |
| |
| if (sdpLines[i] === 'a=extmap-allow-mixed') { |
| extmapAllowMixed = true; |
| } |
| let result = sdpLines[i].match(extmap); |
| if (result && result.length === 2) { |
| if (maxId == undefined || result[1] > maxId) { |
| maxId = parseInt(result[1]); |
| maxIdLine = i; |
| } |
| } |
| } |
| |
| if (maxId == 14 && !extmapAllowMixed) { |
| // Reaching the limit of one byte header extension. Adding two byte header |
| // extension support. |
| sdpLines.splice(maxIdLine + 1, 0, 'a=extmap-allow-mixed'); |
| } |
| if (maxIdLine !== undefined) { |
| sdpLines.splice(maxIdLine + 1, 0, |
| 'a=extmap:' + (maxId + 1).toString() + ' ' + uri); |
| } |
| } |
| return sdpLines.join('\r\n'); |
| } |
| |
| // TODO(crbug.com/1051821): Use RTP header extension API instead of munging |
| // when the RTP header extension API is implemented. |
| async function addAbsCaptureTimeAndExchangeOffer(caller, callee) { |
| let offer = await caller.createOffer(); |
| |
| // Absolute capture time header extension may not be offered by default, |
| // in such case, munge the SDP. |
| offer.sdp = addHeaderExtensionToSdp(offer.sdp, kAbsCaptureTime); |
| |
| await caller.setLocalDescription(offer); |
| return callee.setRemoteDescription(offer); |
| } |
| |
| // TODO(crbug.com/1051821): Use RTP header extension API instead of munging |
| // when the RTP header extension API is implemented. |
| async function checkAbsCaptureTimeAndExchangeAnswer(caller, callee, |
| absCaptureTimeAnswered) { |
| let answer = await callee.createAnswer(); |
| |
| const extmap = new RegExp('a=extmap:\\d+ ' + kAbsCaptureTime + '\r\n', 'g'); |
| if (answer.sdp.match(extmap) == null) { |
| // We expect that absolute capture time RTP header extension is answered. |
| // But if not, there is no need to proceed with the test. |
| assert_false(absCaptureTimeAnswered, 'Absolute capture time RTP ' + |
| 'header extension is not answered'); |
| } else { |
| if (!absCaptureTimeAnswered) { |
| // We expect that absolute capture time RTP header extension is not |
| // answered, but it is, then we munge the answer to remove it. |
| answer.sdp = answer.sdp.replace(extmap, ''); |
| } |
| } |
| |
| await callee.setLocalDescription(answer); |
| return caller.setRemoteDescription(answer); |
| } |
| |
| async function exchangeOfferAndListenToOntrack(t, caller, callee, |
| absCaptureTimeOffered) { |
| const ontrackPromise = addEventListenerPromise(t, callee, 'track'); |
| // Absolute capture time header extension is expected not offered by default, |
| // and thus munging is needed to enable it. |
| await absCaptureTimeOffered |
| ? addAbsCaptureTimeAndExchangeOffer(caller, callee) |
| : exchangeOffer(caller, callee); |
| return ontrackPromise; |
| } |
| |
| async function initiateSingleTrackCall(t, cap, absCaptureTimeOffered, |
| absCaptureTimeAnswered) { |
| const caller = new RTCPeerConnection(); |
| t.add_cleanup(() => caller.close()); |
| const callee = new RTCPeerConnection(); |
| t.add_cleanup(() => callee.close()); |
| |
| const stream = await getNoiseStream(cap); |
| stream.getTracks().forEach(track => { |
| caller.addTrack(track, stream); |
| t.add_cleanup(() => track.stop()); |
| }); |
| |
| // TODO(crbug.com/988432): `getSynchronizationSources() on the audio side |
| // needs a hardware sink for the returned dictionary entries to get updated. |
| const remoteVideo = document.getElementById('remote'); |
| |
| callee.ontrack = e => { |
| remoteVideo.srcObject = e.streams[0]; |
| } |
| |
| exchangeIceCandidates(caller, callee); |
| |
| await exchangeOfferAndListenToOntrack(t, caller, callee, |
| absCaptureTimeOffered); |
| |
| // Exchange answer and check whether the absolute capture time RTP header |
| // extension is answered. |
| await checkAbsCaptureTimeAndExchangeAnswer(caller, callee, |
| absCaptureTimeAnswered); |
| |
| return [caller, callee]; |
| } |