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Improve Call tests for RTX.

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Also does some refactoring to reuse RtpRtcpObserver.

BUG=1811
R=mflodman@webrtc.org, pbos@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/3809004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@5126 4adac7df-926f-26a2-2b94-8c16560cd09d
This commit is contained in:
stefan@webrtc.org
2013-11-15 12:32:15 +00:00
parent 6e95d7afab
commit 69969e2e2f
6 changed files with 114 additions and 119 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
webrtc/call_tests.cc
View File

@@ -31,6 +31,7 @@ namespace webrtc {
static unsigned int kDefaultTimeoutMs = 30 * 1000;
static unsigned int kLongTimeoutMs = 120 * 1000;
static const uint8_t kSendPayloadType = 125;
class CallTest : public ::testing::Test {
public:
@@ -59,6 +60,7 @@ class CallTest : public ::testing::Test {
send_config_.encoder = &fake_encoder_;
send_config_.internal_source = false;
test::FakeEncoder::SetCodecSettings(&send_config_.codec, 1);
send_config_.codec.plType = kSendPayloadType;
receive_config_.codecs.clear();
receive_config_.codecs.push_back(send_config_.codec);

3
webrtc/test/direct_transport.cc
View File

@@ -62,7 +62,8 @@ DirectTransport::Packet::Packet(const uint8_t* data, size_t length)
void DirectTransport::QueuePacket(const uint8_t* data, size_t length) {
CriticalSectionScoped crit(lock_.get());
EXPECT_TRUE(receiver_ != NULL);
if (receiver_ == NULL)
return;
packet_queue_.push_back(Packet(data, length));
packet_event_->Set();
}

1
webrtc/test/fake_encoder.cc
View File

@@ -57,7 +57,6 @@ void FakeEncoder::SetCodecSettings(VideoCodec* codec,
codec->codecType = kVideoCodecGeneric;
strcpy(codec->plName, "FAKE");
codec->plType = 125;
}
int32_t FakeEncoder::InitEncode(const VideoCodec* config,

7
webrtc/test/rtp_rtcp_observer.h
View File

@@ -13,6 +13,7 @@
#include <map>
#include <vector>
#include "webrtc/modules/rtp_rtcp/interface/rtp_header_parser.h"
#include "webrtc/typedefs.h"
#include "webrtc/video_send_stream.h"
@@ -40,12 +41,15 @@ class RtpRtcpObserver {
receive_transport_.StopSending();
}
EventTypeWrapper Wait() { return observation_complete_->Wait(timeout_ms_); }
virtual EventTypeWrapper Wait() {
return observation_complete_->Wait(timeout_ms_);
}
protected:
RtpRtcpObserver(unsigned int event_timeout_ms)
: lock_(CriticalSectionWrapper::CreateCriticalSection()),
observation_complete_(EventWrapper::Create()),
parser_(RtpHeaderParser::Create()),
send_transport_(lock_.get(),
this,
&RtpRtcpObserver::OnSendRtp,
@@ -135,6 +139,7 @@ class RtpRtcpObserver {
protected:
scoped_ptr<CriticalSectionWrapper> lock_;
scoped_ptr<EventWrapper> observation_complete_;
scoped_ptr<RtpHeaderParser> parser_;
private:
PacketTransport send_transport_, receive_transport_;

1
webrtc/video/rampup_tests.cc
View File

@@ -152,6 +152,7 @@ TEST_P(RampUpTest, RampUpWithPadding) {
send_config.encoder = &encoder;
send_config.internal_source = false;
test::FakeEncoder::SetCodecSettings(&send_config.codec, 3);
send_config.codec.plType = 125;
send_config.pacing = GetParam();
send_config.rtp.extensions.push_back(
RtpExtension("toffset", kTOffsetExtensionId));

219
webrtc/video/video_send_stream_tests.cc
View File

@@ -26,32 +26,12 @@
#include "webrtc/test/fake_encoder.h"
#include "webrtc/test/frame_generator_capturer.h"
#include "webrtc/test/null_transport.h"
#include "webrtc/test/rtp_rtcp_observer.h"
#include "webrtc/video/transport_adapter.h"
#include "webrtc/video_send_stream.h"
namespace webrtc {
class SendTransportObserver : public test::NullTransport {
public:
explicit SendTransportObserver(unsigned long timeout_ms)
: rtp_header_parser_(RtpHeaderParser::Create()),
send_test_complete_(EventWrapper::Create()),
timeout_ms_(timeout_ms) {}
virtual EventTypeWrapper Wait() {
return send_test_complete_->Wait(timeout_ms_);
}
virtual void Stop() {}
protected:
scoped_ptr<RtpHeaderParser> rtp_header_parser_;
scoped_ptr<EventWrapper> send_test_complete_;
private:
unsigned long timeout_ms_;
};
class VideoSendStreamTest : public ::testing::Test {
public:
VideoSendStreamTest() : fake_encoder_(Clock::GetRealTimeClock()) {}
@@ -59,7 +39,7 @@ class VideoSendStreamTest : public ::testing::Test {
protected:
void RunSendTest(Call* call,
const VideoSendStream::Config& config,
SendTransportObserver* observer) {
test::RtpRtcpObserver* observer) {
send_stream_ = call->CreateSendStream(config);
scoped_ptr<test::FrameGeneratorCapturer> frame_generator_capturer(
test::FrameGeneratorCapturer::Create(
@@ -69,7 +49,7 @@ class VideoSendStreamTest : public ::testing::Test {
EXPECT_EQ(kEventSignaled, observer->Wait());
observer->Stop();
observer->StopSending();
frame_generator_capturer->Stop();
send_stream_->StopSend();
call->DestroySendStream(send_stream_);
@@ -81,11 +61,17 @@ class VideoSendStreamTest : public ::testing::Test {
config.internal_source = false;
config.rtp.ssrcs.push_back(kSendSsrc);
test::FakeEncoder::SetCodecSettings(&config.codec, 1);
config.codec.plType = kFakeSendPayloadType;
return config;
}
void TestNackRetransmission(uint32_t retransmit_ssrc);
void TestNackRetransmission(uint32_t retransmit_ssrc,
uint8_t retransmit_payload_type,
bool enable_pacing);
static const uint8_t kSendPayloadType;
static const uint8_t kSendRtxPayloadType;
static const uint8_t kFakeSendPayloadType;
static const uint32_t kSendSsrc;
static const uint32_t kSendRtxSsrc;
@@ -93,27 +79,30 @@ class VideoSendStreamTest : public ::testing::Test {
test::FakeEncoder fake_encoder_;
};
const uint8_t VideoSendStreamTest::kSendPayloadType = 100;
const uint8_t VideoSendStreamTest::kFakeSendPayloadType = 125;
const uint8_t VideoSendStreamTest::kSendRtxPayloadType = 98;
const uint32_t VideoSendStreamTest::kSendSsrc = 0xC0FFEE;
const uint32_t VideoSendStreamTest::kSendRtxSsrc = 0xBADCAFE;
TEST_F(VideoSendStreamTest, SendsSetSsrc) {
class SendSsrcObserver : public SendTransportObserver {
class SendSsrcObserver : public test::RtpRtcpObserver {
public:
SendSsrcObserver() : SendTransportObserver(30 * 1000) {}
SendSsrcObserver() : RtpRtcpObserver(30 * 1000) {}
virtual bool SendRTP(const uint8_t* packet, size_t length) OVERRIDE {
virtual Action OnSendRtp(const uint8_t* packet, size_t length) OVERRIDE {
RTPHeader header;
EXPECT_TRUE(
rtp_header_parser_->Parse(packet, static_cast<int>(length), &header));
parser_->Parse(packet, static_cast<int>(length), &header));
if (header.ssrc == kSendSsrc)
send_test_complete_->Set();
observation_complete_->Set();
return true;
return SEND_PACKET;
}
} observer;
Call::Config call_config(&observer);
Call::Config call_config(observer.SendTransport());
scoped_ptr<Call> call(Call::Create(call_config));
VideoSendStream::Config send_config = GetSendTestConfig(call.get());
@@ -124,11 +113,11 @@ TEST_F(VideoSendStreamTest, SendsSetSsrc) {
TEST_F(VideoSendStreamTest, SupportsCName) {
static std::string kCName = "PjQatC14dGfbVwGPUOA9IH7RlsFDbWl4AhXEiDsBizo=";
class CNameObserver : public SendTransportObserver {
class CNameObserver : public test::RtpRtcpObserver {
public:
CNameObserver() : SendTransportObserver(30 * 1000) {}
CNameObserver() : RtpRtcpObserver(30 * 1000) {}
virtual bool SendRTCP(const uint8_t* packet, size_t length) OVERRIDE {
virtual Action OnSendRtcp(const uint8_t* packet, size_t length) OVERRIDE {
RTCPUtility::RTCPParserV2 parser(packet, length, true);
EXPECT_TRUE(parser.IsValid());
@@ -136,17 +125,17 @@ TEST_F(VideoSendStreamTest, SupportsCName) {
while (packet_type != RTCPUtility::kRtcpNotValidCode) {
if (packet_type == RTCPUtility::kRtcpSdesChunkCode) {
EXPECT_EQ(parser.Packet().CName.CName, kCName);
send_test_complete_->Set();
observation_complete_->Set();
}
packet_type = parser.Iterate();
}
return true;
return SEND_PACKET;
}
} observer;
Call::Config call_config(&observer);
Call::Config call_config(observer.SendTransport());
scoped_ptr<Call> call(Call::Create(call_config));
VideoSendStream::Config send_config = GetSendTestConfig(call.get());
@@ -157,26 +146,26 @@ TEST_F(VideoSendStreamTest, SupportsCName) {
TEST_F(VideoSendStreamTest, SupportsAbsoluteSendTime) {
static const uint8_t kAbsSendTimeExtensionId = 13;
class AbsoluteSendTimeObserver : public SendTransportObserver {
class AbsoluteSendTimeObserver : public test::RtpRtcpObserver {
public:
AbsoluteSendTimeObserver() : SendTransportObserver(30 * 1000) {
EXPECT_TRUE(rtp_header_parser_->RegisterRtpHeaderExtension(
AbsoluteSendTimeObserver() : RtpRtcpObserver(30 * 1000) {
EXPECT_TRUE(parser_->RegisterRtpHeaderExtension(
kRtpExtensionAbsoluteSendTime, kAbsSendTimeExtensionId));
}
virtual bool SendRTP(const uint8_t* packet, size_t length) OVERRIDE {
virtual Action OnSendRtp(const uint8_t* packet, size_t length) OVERRIDE {
RTPHeader header;
EXPECT_TRUE(
rtp_header_parser_->Parse(packet, static_cast<int>(length), &header));
parser_->Parse(packet, static_cast<int>(length), &header));
if (header.extension.absoluteSendTime > 0)
send_test_complete_->Set();
observation_complete_->Set();
return true;
return SEND_PACKET;
}
} observer;
Call::Config call_config(&observer);
Call::Config call_config(observer.SendTransport());
scoped_ptr<Call> call(Call::Create(call_config));
VideoSendStream::Config send_config = GetSendTestConfig(call.get());
@@ -202,26 +191,26 @@ TEST_F(VideoSendStreamTest, SupportsTransmissionTimeOffset) {
}
} encoder(Clock::GetRealTimeClock());
class TransmissionTimeOffsetObserver : public SendTransportObserver {
class TransmissionTimeOffsetObserver : public test::RtpRtcpObserver {
public:
TransmissionTimeOffsetObserver() : SendTransportObserver(30 * 1000) {
EXPECT_TRUE(rtp_header_parser_->RegisterRtpHeaderExtension(
TransmissionTimeOffsetObserver() : RtpRtcpObserver(30 * 1000) {
EXPECT_TRUE(parser_->RegisterRtpHeaderExtension(
kRtpExtensionTransmissionTimeOffset, kTOffsetExtensionId));
}
virtual bool SendRTP(const uint8_t* packet, size_t length) OVERRIDE {
virtual Action OnSendRtp(const uint8_t* packet, size_t length) OVERRIDE {
RTPHeader header;
EXPECT_TRUE(
rtp_header_parser_->Parse(packet, static_cast<int>(length), &header));
parser_->Parse(packet, static_cast<int>(length), &header));
EXPECT_GT(header.extension.transmissionTimeOffset, 0);
send_test_complete_->Set();
observation_complete_->Set();
return true;
return SEND_PACKET;
}
} observer;
Call::Config call_config(&observer);
Call::Config call_config(observer.SendTransport());
scoped_ptr<Call> call(Call::Create(call_config));
VideoSendStream::Config send_config = GetSendTestConfig(call.get());
@@ -291,23 +280,19 @@ class FakeReceiveStatistics : public NullReceiveStatistics {
TEST_F(VideoSendStreamTest, SupportsFec) {
static const int kRedPayloadType = 118;
static const int kUlpfecPayloadType = 119;
class FecObserver : public SendTransportObserver {
class FecObserver : public test::RtpRtcpObserver {
public:
FecObserver()
: SendTransportObserver(30 * 1000),
transport_adapter_(&transport_),
: RtpRtcpObserver(30 * 1000),
transport_adapter_(SendTransport()),
send_count_(0),
received_media_(false),
received_fec_(false) {}
void SetReceiver(PacketReceiver* receiver) {
transport_.SetReceiver(receiver);
}
virtual bool SendRTP(const uint8_t* packet, size_t length) OVERRIDE {
virtual Action OnSendRtp(const uint8_t* packet, size_t length) OVERRIDE {
RTPHeader header;
EXPECT_TRUE(
rtp_header_parser_->Parse(packet, static_cast<int>(length), &header));
parser_->Parse(packet, static_cast<int>(length), &header));
// Send lossy receive reports to trigger FEC enabling.
if (send_count_++ % 2 != 0) {
@@ -337,25 +322,22 @@ TEST_F(VideoSendStreamTest, SupportsFec) {
}
if (received_media_ && received_fec_)
send_test_complete_->Set();
observation_complete_->Set();
return true;
return SEND_PACKET;
}
virtual void Stop() OVERRIDE { transport_.StopSending(); }
private:
internal::TransportAdapter transport_adapter_;
test::DirectTransport transport_;
int send_count_;
bool received_media_;
bool received_fec_;
} observer;
Call::Config call_config(&observer);
Call::Config call_config(observer.SendTransport());
scoped_ptr<Call> call(Call::Create(call_config));
observer.SetReceiver(call->Receiver());
observer.SetReceivers(call->Receiver(), NULL);
VideoSendStream::Config send_config = GetSendTestConfig(call.get());
send_config.rtp.fec.red_payload_type = kRedPayloadType;
@@ -364,24 +346,25 @@ TEST_F(VideoSendStreamTest, SupportsFec) {
RunSendTest(call.get(), send_config, &observer);
}
void VideoSendStreamTest::TestNackRetransmission(uint32_t retransmit_ssrc) {
class NackObserver : public SendTransportObserver {
void VideoSendStreamTest::TestNackRetransmission(
uint32_t retransmit_ssrc,
uint8_t retransmit_payload_type,
bool enable_pacing) {
class NackObserver : public test::RtpRtcpObserver {
public:
explicit NackObserver(uint32_t retransmit_ssrc)
: SendTransportObserver(30 * 1000),
transport_adapter_(&transport_),
explicit NackObserver(uint32_t retransmit_ssrc,
uint8_t retransmit_payload_type)
: RtpRtcpObserver(30 * 1000),
transport_adapter_(SendTransport()),
send_count_(0),
retransmit_ssrc_(retransmit_ssrc),
retransmit_payload_type_(retransmit_payload_type),
nacked_sequence_number_(0) {}
void SetReceiver(PacketReceiver* receiver) {
transport_.SetReceiver(receiver);
}
virtual bool SendRTP(const uint8_t* packet, size_t length) OVERRIDE {
virtual Action OnSendRtp(const uint8_t* packet, size_t length) OVERRIDE {
RTPHeader header;
EXPECT_TRUE(
rtp_header_parser_->Parse(packet, static_cast<int>(length), &header));
parser_->Parse(packet, static_cast<int>(length), &header));
// Nack second packet after receiving the third one.
if (++send_count_ == 3) {
@@ -411,28 +394,29 @@ void VideoSendStreamTest::TestNackRetransmission(uint32_t retransmit_ssrc) {
if (sequence_number == nacked_sequence_number_) {
EXPECT_EQ(retransmit_ssrc_, header.ssrc);
send_test_complete_->Set();
EXPECT_EQ(retransmit_payload_type_, header.payloadType);
observation_complete_->Set();
}
return true;
return SEND_PACKET;
}
virtual void Stop() OVERRIDE { transport_.StopSending(); }
private:
internal::TransportAdapter transport_adapter_;
test::DirectTransport transport_;
int send_count_;
uint32_t retransmit_ssrc_;
uint8_t retransmit_payload_type_;
uint16_t nacked_sequence_number_;
} observer(retransmit_ssrc);
} observer(retransmit_ssrc, retransmit_payload_type);
Call::Config call_config(&observer);
Call::Config call_config(observer.SendTransport());
scoped_ptr<Call> call(Call::Create(call_config));
observer.SetReceiver(call->Receiver());
observer.SetReceivers(call->Receiver(), NULL);
VideoSendStream::Config send_config = GetSendTestConfig(call.get());
send_config.rtp.nack.rtp_history_ms = 1000;
send_config.rtp.rtx.rtx_payload_type = retransmit_payload_type;
send_config.pacing = enable_pacing;
if (retransmit_ssrc != kSendSsrc)
send_config.rtp.rtx.ssrcs.push_back(retransmit_ssrc);
@@ -441,24 +425,29 @@ void VideoSendStreamTest::TestNackRetransmission(uint32_t retransmit_ssrc) {
TEST_F(VideoSendStreamTest, RetransmitsNack) {
// Normal NACKs should use the send SSRC.
TestNackRetransmission(kSendSsrc);
TestNackRetransmission(kSendSsrc, kFakeSendPayloadType, false);
}
TEST_F(VideoSendStreamTest, RetransmitsNackOverRtx) {
// NACKs over RTX should use a separate SSRC.
TestNackRetransmission(kSendRtxSsrc);
TestNackRetransmission(kSendRtxSsrc, kSendRtxPayloadType, false);
}
TEST_F(VideoSendStreamTest, RetransmitsNackOverRtxWithPacing) {
// NACKs over RTX should use a separate SSRC.
TestNackRetransmission(kSendRtxSsrc, kSendRtxPayloadType, true);
}
TEST_F(VideoSendStreamTest, MaxPacketSize) {
class PacketSizeObserver : public SendTransportObserver {
class PacketSizeObserver : public test::RtpRtcpObserver {
public:
PacketSizeObserver(size_t max_length) : SendTransportObserver(30 * 1000),
PacketSizeObserver(size_t max_length) : RtpRtcpObserver(30 * 1000),
max_length_(max_length), accumulated_size_(0) {}
virtual bool SendRTP(const uint8_t* packet, size_t length) OVERRIDE {
virtual Action OnSendRtp(const uint8_t* packet, size_t length) OVERRIDE {
RTPHeader header;
EXPECT_TRUE(
rtp_header_parser_->Parse(packet, static_cast<int>(length), &header));
parser_->Parse(packet, static_cast<int>(length), &header));
EXPECT_LE(length, max_length_);
@@ -469,12 +458,12 @@ TEST_F(VideoSendStreamTest, MaxPacketSize) {
if (accumulated_size_ + length > max_length_) {
// The packet was fragmented, total size was larger than max size,
// but size of individual fragments were within size limit => pass!
send_test_complete_->Set();
observation_complete_->Set();
}
accumulated_size_ = 0; // Last fragment, reset packet size
}
return true;
return SEND_PACKET;
}
private:
@@ -485,7 +474,7 @@ TEST_F(VideoSendStreamTest, MaxPacketSize) {
static const uint32_t kMaxPacketSize = 128;
PacketSizeObserver observer(kMaxPacketSize);
Call::Config call_config(&observer);
Call::Config call_config(observer.SendTransport());
scoped_ptr<Call> call(Call::Create(call_config));
VideoSendStream::Config send_config = GetSendTestConfig(call.get());
@@ -498,25 +487,24 @@ TEST_F(VideoSendStreamTest, CanChangeSendCodec) {
static const uint8_t kFirstPayloadType = 121;
static const uint8_t kSecondPayloadType = 122;
class CodecChangeObserver : public SendTransportObserver {
class CodecChangeObserver : public test::RtpRtcpObserver {
public:
CodecChangeObserver(VideoSendStream** send_stream_ptr)
: SendTransportObserver(30 * 1000),
: RtpRtcpObserver(30 * 1000),
received_first_payload_(EventWrapper::Create()),
send_stream_ptr_(send_stream_ptr) {}
virtual bool SendRTP(const uint8_t* packet, size_t length) OVERRIDE {
virtual Action OnSendRtp(const uint8_t* packet, size_t length) OVERRIDE {
RTPHeader header;
EXPECT_TRUE(
rtp_header_parser_->Parse(packet, static_cast<int>(length), &header));
EXPECT_TRUE(parser_->Parse(packet, static_cast<int>(length), &header));
if (header.payloadType == kFirstPayloadType) {
received_first_payload_->Set();
} else if (header.payloadType == kSecondPayloadType) {
send_test_complete_->Set();
observation_complete_->Set();
}
return true;
return SEND_PACKET;
}
virtual EventTypeWrapper Wait() OVERRIDE {
@@ -525,7 +513,7 @@ TEST_F(VideoSendStreamTest, CanChangeSendCodec) {
EXPECT_TRUE((*send_stream_ptr_)->SetCodec(second_codec_));
EXPECT_EQ(kEventSignaled, SendTransportObserver::Wait())
EXPECT_EQ(kEventSignaled, RtpRtcpObserver::Wait())
<< "Timed out while waiting for second payload type.";
// Return OK regardless, prevents double error reporting.
@@ -542,7 +530,7 @@ TEST_F(VideoSendStreamTest, CanChangeSendCodec) {
VideoCodec second_codec_;
} observer(&send_stream_);
Call::Config call_config(&observer);
Call::Config call_config(observer.SendTransport());
scoped_ptr<Call> call(Call::Create(call_config));
std::vector<VideoCodec> codecs = call->GetVideoCodecs();
@@ -570,10 +558,10 @@ TEST_F(VideoSendStreamTest, CanChangeSendCodec) {
TEST_F(VideoSendStreamTest, AutoMute) {
static const int kMuteTimeFrames = 60; // Mute for 2 seconds @ 30 fps.
class RembObserver : public SendTransportObserver, public I420FrameCallback {
class RembObserver : public test::RtpRtcpObserver, public I420FrameCallback {
public:
RembObserver()
: SendTransportObserver(30 * 1000), // Timeout after 30 seconds.
: RtpRtcpObserver(30 * 1000), // Timeout after 30 seconds.
transport_adapter_(&transport_),
clock_(Clock::GetRealTimeClock()),
test_state_(kBeforeMute),
@@ -588,20 +576,19 @@ TEST_F(VideoSendStreamTest, AutoMute) {
transport_.SetReceiver(receiver);
}
virtual bool SendRTCP(const uint8_t* packet, size_t length) OVERRIDE {
virtual Action OnSendRtcp(const uint8_t* packet, size_t length) OVERRIDE {
// Receive statistics reporting having lost 0% of the packets.
// This is needed for the send-side bitrate controller to work properly.
CriticalSectionScoped lock(crit_sect_.get());
SendRtcpFeedback(0); // REMB is only sent if value is > 0.
return true;
return SEND_PACKET;
}
virtual bool SendRTP(const uint8_t* packet, size_t length) OVERRIDE {
virtual Action OnSendRtp(const uint8_t* packet, size_t length) OVERRIDE {
CriticalSectionScoped lock(crit_sect_.get());
++rtp_count_;
RTPHeader header;
EXPECT_TRUE(
rtp_header_parser_->Parse(packet, static_cast<int>(length), &header));
EXPECT_TRUE(parser_->Parse(packet, static_cast<int>(length), &header));
last_sequence_number_ = header.sequenceNumber;
if (test_state_ == kBeforeMute) {
@@ -611,10 +598,10 @@ TEST_F(VideoSendStreamTest, AutoMute) {
} else if (test_state_ == kDuringMute) {
mute_frame_count_ = 0;
} else if (test_state_ == kWaitingForPacket) {
send_test_complete_->Set();
observation_complete_->Set();
}
return true;
return SEND_PACKET;
}
// This method implements the I420FrameCallback.
@@ -668,7 +655,7 @@ TEST_F(VideoSendStreamTest, AutoMute) {
scoped_ptr<CriticalSectionWrapper> crit_sect_;
} observer;
Call::Config call_config(&observer);
Call::Config call_config(observer.SendTransport());
scoped_ptr<Call> call(Call::Create(call_config));
observer.SetReceiver(call->Receiver());