blob: 703f7a9634c9a03a1e6271629b5140323dc3476e [file] [log] [blame]
/*
* Copyright (c) 2013 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include <stdio.h>
#include <string.h>
#include <memory>
#include <string>
#include <vector>
#include "absl/algorithm/container.h"
#include "media/sctp/sctp_transport.h"
#include "p2p/base/fake_dtls_transport.h"
#include "rtc_base/copy_on_write_buffer.h"
#include "rtc_base/gunit.h"
#include "rtc_base/logging.h"
#include "rtc_base/message_queue.h"
#include "rtc_base/thread.h"
#include "test/gtest.h"
namespace {
static const int kDefaultTimeout = 10000; // 10 seconds.
// Use ports other than the default 5000 for testing.
static const int kTransport1Port = 5001;
static const int kTransport2Port = 5002;
} // namespace
namespace cricket {
// This is essentially a buffer to hold recieved data. It stores only the last
// received data. Calling OnDataReceived twice overwrites old data with the
// newer one.
// TODO(ldixon): Implement constraints, and allow new data to be added to old
// instead of replacing it.
class SctpFakeDataReceiver : public sigslot::has_slots<> {
public:
SctpFakeDataReceiver() : received_(false) {}
void Clear() {
received_ = false;
last_data_ = "";
last_params_ = ReceiveDataParams();
}
void OnDataReceived(const ReceiveDataParams& params,
const rtc::CopyOnWriteBuffer& data) {
received_ = true;
last_data_ = std::string(data.data<char>(), data.size());
last_params_ = params;
}
bool received() const { return received_; }
std::string last_data() const { return last_data_; }
ReceiveDataParams last_params() const { return last_params_; }
private:
bool received_;
std::string last_data_;
ReceiveDataParams last_params_;
};
class SctpTransportObserver : public sigslot::has_slots<> {
public:
explicit SctpTransportObserver(SctpTransport* transport) {
transport->SignalClosingProcedureComplete.connect(
this, &SctpTransportObserver::OnClosingProcedureComplete);
transport->SignalReadyToSendData.connect(
this, &SctpTransportObserver::OnReadyToSend);
}
int StreamCloseCount(int stream) {
return absl::c_count(closed_streams_, stream);
}
bool WasStreamClosed(int stream) {
return absl::c_linear_search(closed_streams_, stream);
}
bool ReadyToSend() { return ready_to_send_; }
private:
void OnClosingProcedureComplete(int stream) {
closed_streams_.push_back(stream);
}
void OnReadyToSend() { ready_to_send_ = true; }
std::vector<int> closed_streams_;
bool ready_to_send_ = false;
};
// Helper class used to immediately attempt to reopen a stream as soon as it's
// been closed.
class SignalTransportClosedReopener : public sigslot::has_slots<> {
public:
SignalTransportClosedReopener(SctpTransport* transport, SctpTransport* peer)
: transport_(transport), peer_(peer) {}
int StreamCloseCount(int stream) { return absl::c_count(streams_, stream); }
private:
void OnStreamClosed(int stream) {
transport_->OpenStream(stream);
peer_->OpenStream(stream);
streams_.push_back(stream);
}
SctpTransport* transport_;
SctpTransport* peer_;
std::vector<int> streams_;
};
// SCTP Data Engine testing framework.
class SctpTransportTest : public ::testing::Test, public sigslot::has_slots<> {
protected:
// usrsctp uses the NSS random number generator on non-Android platforms,
// so we need to initialize SSL.
static void SetUpTestSuite() {}
void SetupConnectedTransportsWithTwoStreams() {
SetupConnectedTransportsWithTwoStreams(kTransport1Port, kTransport2Port);
}
void SetupConnectedTransportsWithTwoStreams(int port1, int port2) {
fake_dtls1_.reset(new FakeDtlsTransport("fake dtls 1", 0));
fake_dtls2_.reset(new FakeDtlsTransport("fake dtls 2", 0));
recv1_.reset(new SctpFakeDataReceiver());
recv2_.reset(new SctpFakeDataReceiver());
transport1_.reset(CreateTransport(fake_dtls1_.get(), recv1_.get()));
transport1_->set_debug_name_for_testing("transport1");
transport1_->SignalReadyToSendData.connect(
this, &SctpTransportTest::OnChan1ReadyToSend);
transport2_.reset(CreateTransport(fake_dtls2_.get(), recv2_.get()));
transport2_->set_debug_name_for_testing("transport2");
transport2_->SignalReadyToSendData.connect(
this, &SctpTransportTest::OnChan2ReadyToSend);
// Setup two connected transports ready to send and receive.
bool asymmetric = false;
fake_dtls1_->SetDestination(fake_dtls2_.get(), asymmetric);
RTC_LOG(LS_VERBOSE) << "Transport setup ----------------------------- ";
AddStream(1);
AddStream(2);
RTC_LOG(LS_VERBOSE)
<< "Connect the transports -----------------------------";
// Both transports need to have started (with matching ports) for an
// association to be formed.
transport1_->Start(port1, port2, kSctpSendBufferSize);
transport2_->Start(port2, port1, kSctpSendBufferSize);
}
bool AddStream(int sid) {
bool ret = true;
ret = ret && transport1_->OpenStream(sid);
ret = ret && transport2_->OpenStream(sid);
return ret;
}
SctpTransport* CreateTransport(FakeDtlsTransport* fake_dtls,
SctpFakeDataReceiver* recv) {
SctpTransport* transport =
new SctpTransport(rtc::Thread::Current(), fake_dtls);
// When data is received, pass it to the SctpFakeDataReceiver.
transport->SignalDataReceived.connect(
recv, &SctpFakeDataReceiver::OnDataReceived);
return transport;
}
bool SendData(SctpTransport* chan,
int sid,
const std::string& msg,
SendDataResult* result) {
SendDataParams params;
params.sid = sid;
return chan->SendData(params, rtc::CopyOnWriteBuffer(&msg[0], msg.length()),
result);
}
bool ReceivedData(const SctpFakeDataReceiver* recv,
int sid,
const std::string& msg) {
return (recv->received() && recv->last_params().sid == sid &&
recv->last_data() == msg);
}
bool ProcessMessagesUntilIdle() {
rtc::Thread* thread = rtc::Thread::Current();
while (!thread->empty()) {
rtc::Message msg;
if (thread->Get(&msg, rtc::Thread::kForever)) {
thread->Dispatch(&msg);
}
}
return !thread->IsQuitting();
}
SctpTransport* transport1() { return transport1_.get(); }
SctpTransport* transport2() { return transport2_.get(); }
SctpFakeDataReceiver* receiver1() { return recv1_.get(); }
SctpFakeDataReceiver* receiver2() { return recv2_.get(); }
FakeDtlsTransport* fake_dtls1() { return fake_dtls1_.get(); }
FakeDtlsTransport* fake_dtls2() { return fake_dtls2_.get(); }
int transport1_ready_to_send_count() {
return transport1_ready_to_send_count_;
}
int transport2_ready_to_send_count() {
return transport2_ready_to_send_count_;
}
private:
std::unique_ptr<FakeDtlsTransport> fake_dtls1_;
std::unique_ptr<FakeDtlsTransport> fake_dtls2_;
std::unique_ptr<SctpFakeDataReceiver> recv1_;
std::unique_ptr<SctpFakeDataReceiver> recv2_;
std::unique_ptr<SctpTransport> transport1_;
std::unique_ptr<SctpTransport> transport2_;
int transport1_ready_to_send_count_ = 0;
int transport2_ready_to_send_count_ = 0;
void OnChan1ReadyToSend() { ++transport1_ready_to_send_count_; }
void OnChan2ReadyToSend() { ++transport2_ready_to_send_count_; }
};
// Test that data can be sent end-to-end when an SCTP transport starts with one
// transport (which is unwritable), and then switches to another transport. A
// common scenario due to how BUNDLE works.
TEST_F(SctpTransportTest, SwitchDtlsTransport) {
FakeDtlsTransport black_hole("black hole", 0);
FakeDtlsTransport fake_dtls1("fake dtls 1", 0);
FakeDtlsTransport fake_dtls2("fake dtls 2", 0);
SctpFakeDataReceiver recv1;
SctpFakeDataReceiver recv2;
// Construct transport1 with the "black hole" transport.
std::unique_ptr<SctpTransport> transport1(
CreateTransport(&black_hole, &recv1));
std::unique_ptr<SctpTransport> transport2(
CreateTransport(&fake_dtls2, &recv2));
// Add a stream.
transport1->OpenStream(1);
transport2->OpenStream(1);
// Tell them both to start (though transport1_ is connected to black_hole).
transport1->Start(kTransport1Port, kTransport2Port, kSctpSendBufferSize);
transport2->Start(kTransport2Port, kTransport1Port, kSctpSendBufferSize);
// Switch transport1_ to the normal fake_dtls1_ transport.
transport1->SetDtlsTransport(&fake_dtls1);
// Connect the two fake DTLS transports.
bool asymmetric = false;
fake_dtls1.SetDestination(&fake_dtls2, asymmetric);
// Make sure we end up able to send data.
SendDataResult result;
ASSERT_TRUE(SendData(transport1.get(), 1, "foo", &result));
ASSERT_TRUE(SendData(transport2.get(), 1, "bar", &result));
EXPECT_TRUE_WAIT(ReceivedData(&recv2, 1, "foo"), kDefaultTimeout);
EXPECT_TRUE_WAIT(ReceivedData(&recv1, 1, "bar"), kDefaultTimeout);
// Setting a null DtlsTransport should work. This could happen when an SCTP
// data section is rejected.
transport1->SetDtlsTransport(nullptr);
}
// Calling Start twice shouldn't do anything bad, if with the same parameters.
TEST_F(SctpTransportTest, DuplicateStartCallsIgnored) {
SetupConnectedTransportsWithTwoStreams();
EXPECT_TRUE(transport1()->Start(kTransport1Port, kTransport2Port,
kSctpSendBufferSize));
// Make sure we can still send/recv data.
SendDataResult result;
ASSERT_TRUE(SendData(transport1(), 1, "foo", &result));
ASSERT_TRUE(SendData(transport2(), 1, "bar", &result));
EXPECT_TRUE_WAIT(ReceivedData(receiver2(), 1, "foo"), kDefaultTimeout);
EXPECT_TRUE_WAIT(ReceivedData(receiver1(), 1, "bar"), kDefaultTimeout);
}
// Calling Start a second time with a different port should fail.
TEST_F(SctpTransportTest, CallingStartWithDifferentPortFails) {
SetupConnectedTransportsWithTwoStreams();
EXPECT_FALSE(transport1()->Start(kTransport1Port, 1234, kSctpSendBufferSize));
EXPECT_FALSE(transport1()->Start(1234, kTransport2Port, kSctpSendBufferSize));
}
// A value of -1 for the local/remote port should be treated as the default
// (5000).
TEST_F(SctpTransportTest, NegativeOnePortTreatedAsDefault) {
FakeDtlsTransport fake_dtls1("fake dtls 1", 0);
FakeDtlsTransport fake_dtls2("fake dtls 2", 0);
SctpFakeDataReceiver recv1;
SctpFakeDataReceiver recv2;
std::unique_ptr<SctpTransport> transport1(
CreateTransport(&fake_dtls1, &recv1));
std::unique_ptr<SctpTransport> transport2(
CreateTransport(&fake_dtls2, &recv2));
// Add a stream.
transport1->OpenStream(1);
transport2->OpenStream(1);
// Tell them both to start, giving one transport the default port and the
// other transport -1.
transport1->Start(kSctpDefaultPort, kSctpDefaultPort, kSctpSendBufferSize);
transport2->Start(-1, -1, kSctpSendBufferSize);
// Connect the two fake DTLS transports.
bool asymmetric = false;
fake_dtls1.SetDestination(&fake_dtls2, asymmetric);
// Make sure we end up able to send data.
SendDataResult result;
ASSERT_TRUE(SendData(transport1.get(), 1, "foo", &result));
ASSERT_TRUE(SendData(transport2.get(), 1, "bar", &result));
EXPECT_TRUE_WAIT(ReceivedData(&recv2, 1, "foo"), kDefaultTimeout);
EXPECT_TRUE_WAIT(ReceivedData(&recv1, 1, "bar"), kDefaultTimeout);
}
TEST_F(SctpTransportTest, OpenStreamWithAlreadyOpenedStreamFails) {
FakeDtlsTransport fake_dtls("fake dtls", 0);
SctpFakeDataReceiver recv;
std::unique_ptr<SctpTransport> transport(CreateTransport(&fake_dtls, &recv));
EXPECT_TRUE(transport->OpenStream(1));
EXPECT_FALSE(transport->OpenStream(1));
}
TEST_F(SctpTransportTest, ResetStreamWithAlreadyResetStreamFails) {
FakeDtlsTransport fake_dtls("fake dtls", 0);
SctpFakeDataReceiver recv;
std::unique_ptr<SctpTransport> transport(CreateTransport(&fake_dtls, &recv));
EXPECT_TRUE(transport->OpenStream(1));
EXPECT_TRUE(transport->ResetStream(1));
EXPECT_FALSE(transport->ResetStream(1));
}
// Test that SignalReadyToSendData is fired after Start has been called and the
// DTLS transport is writable.
TEST_F(SctpTransportTest, SignalReadyToSendDataAfterDtlsWritable) {
FakeDtlsTransport fake_dtls("fake dtls", 0);
SctpFakeDataReceiver recv;
std::unique_ptr<SctpTransport> transport(CreateTransport(&fake_dtls, &recv));
SctpTransportObserver observer(transport.get());
transport->Start(kSctpDefaultPort, kSctpDefaultPort, kSctpSendBufferSize);
fake_dtls.SetWritable(true);
EXPECT_TRUE_WAIT(observer.ReadyToSend(), kDefaultTimeout);
}
// Test that after an SCTP socket's buffer is filled, SignalReadyToSendData
// is fired after it begins to be drained.
TEST_F(SctpTransportTest, SignalReadyToSendDataAfterBlocked) {
SetupConnectedTransportsWithTwoStreams();
// Wait for initial SCTP association to be formed.
EXPECT_EQ_WAIT(1, transport1_ready_to_send_count(), kDefaultTimeout);
// Make the fake transport unwritable so that messages pile up for the SCTP
// socket.
fake_dtls1()->SetWritable(false);
// Send messages until we get EWOULDBLOCK.
static const int kMaxMessages = 1024;
SendDataParams params;
params.sid = 1;
rtc::CopyOnWriteBuffer buf(1024);
memset(buf.data<uint8_t>(), 0, 1024);
SendDataResult result;
int message_count;
for (message_count = 0; message_count < kMaxMessages; ++message_count) {
if (!transport1()->SendData(params, buf, &result) && result == SDR_BLOCK) {
break;
}
}
ASSERT_NE(kMaxMessages, message_count)
<< "Sent max number of messages without getting SDR_BLOCK?";
// Make sure the ready-to-send count hasn't changed.
EXPECT_EQ(1, transport1_ready_to_send_count());
// Make the transport writable again and expect a "SignalReadyToSendData" at
// some point.
fake_dtls1()->SetWritable(true);
EXPECT_EQ_WAIT(2, transport1_ready_to_send_count(), kDefaultTimeout);
}
TEST_F(SctpTransportTest, SendData) {
SetupConnectedTransportsWithTwoStreams();
SendDataResult result;
RTC_LOG(LS_VERBOSE)
<< "transport1 sending: 'hello?' -----------------------------";
ASSERT_TRUE(SendData(transport1(), 1, "hello?", &result));
EXPECT_EQ(SDR_SUCCESS, result);
EXPECT_TRUE_WAIT(ReceivedData(receiver2(), 1, "hello?"), kDefaultTimeout);
RTC_LOG(LS_VERBOSE) << "recv2.received=" << receiver2()->received()
<< ", recv2.last_params.sid="
<< receiver2()->last_params().sid
<< ", recv2.last_params.timestamp="
<< receiver2()->last_params().timestamp
<< ", recv2.last_params.seq_num="
<< receiver2()->last_params().seq_num
<< ", recv2.last_data=" << receiver2()->last_data();
RTC_LOG(LS_VERBOSE)
<< "transport2 sending: 'hi transport1' -----------------------------";
ASSERT_TRUE(SendData(transport2(), 2, "hi transport1", &result));
EXPECT_EQ(SDR_SUCCESS, result);
EXPECT_TRUE_WAIT(ReceivedData(receiver1(), 2, "hi transport1"),
kDefaultTimeout);
RTC_LOG(LS_VERBOSE) << "recv1.received=" << receiver1()->received()
<< ", recv1.last_params.sid="
<< receiver1()->last_params().sid
<< ", recv1.last_params.timestamp="
<< receiver1()->last_params().timestamp
<< ", recv1.last_params.seq_num="
<< receiver1()->last_params().seq_num
<< ", recv1.last_data=" << receiver1()->last_data();
}
// Sends a lot of large messages at once and verifies SDR_BLOCK is returned.
TEST_F(SctpTransportTest, SendDataBlocked) {
SetupConnectedTransportsWithTwoStreams();
SendDataResult result;
SendDataParams params;
params.sid = 1;
std::vector<char> buffer(1024 * 64, 0);
for (size_t i = 0; i < 100; ++i) {
transport1()->SendData(
params, rtc::CopyOnWriteBuffer(&buffer[0], buffer.size()), &result);
if (result == SDR_BLOCK)
break;
}
EXPECT_EQ(SDR_BLOCK, result);
}
// Trying to send data for a nonexistent stream should fail.
TEST_F(SctpTransportTest, SendDataWithNonexistentStreamFails) {
SetupConnectedTransportsWithTwoStreams();
SendDataResult result;
EXPECT_FALSE(SendData(transport2(), 123, "some data", &result));
EXPECT_EQ(SDR_ERROR, result);
}
TEST_F(SctpTransportTest, SendDataHighPorts) {
SetupConnectedTransportsWithTwoStreams(32768, 32769);
SendDataResult result;
ASSERT_TRUE(SendData(transport1(), 1, "hello?", &result));
EXPECT_EQ(SDR_SUCCESS, result);
EXPECT_TRUE_WAIT(ReceivedData(receiver2(), 1, "hello?"), kDefaultTimeout);
ASSERT_TRUE(SendData(transport2(), 2, "hi transport1", &result));
EXPECT_EQ(SDR_SUCCESS, result);
EXPECT_TRUE_WAIT(ReceivedData(receiver1(), 2, "hi transport1"),
kDefaultTimeout);
}
TEST_F(SctpTransportTest, ClosesRemoteStream) {
SetupConnectedTransportsWithTwoStreams();
SctpTransportObserver transport1_observer(transport1());
SctpTransportObserver transport2_observer(transport2());
SendDataResult result;
ASSERT_TRUE(SendData(transport1(), 1, "hello?", &result));
EXPECT_EQ(SDR_SUCCESS, result);
EXPECT_TRUE_WAIT(ReceivedData(receiver2(), 1, "hello?"), kDefaultTimeout);
ASSERT_TRUE(SendData(transport2(), 2, "hi transport1", &result));
EXPECT_EQ(SDR_SUCCESS, result);
EXPECT_TRUE_WAIT(ReceivedData(receiver1(), 2, "hi transport1"),
kDefaultTimeout);
// Close stream 1 on transport 1. Transport 2 should notify us.
transport1()->ResetStream(1);
EXPECT_TRUE_WAIT(transport2_observer.WasStreamClosed(1), kDefaultTimeout);
}
TEST_F(SctpTransportTest, ClosesTwoRemoteStreams) {
SetupConnectedTransportsWithTwoStreams();
AddStream(3);
SctpTransportObserver transport1_observer(transport1());
SctpTransportObserver transport2_observer(transport2());
SendDataResult result;
ASSERT_TRUE(SendData(transport1(), 1, "hello?", &result));
EXPECT_EQ(SDR_SUCCESS, result);
EXPECT_TRUE_WAIT(ReceivedData(receiver2(), 1, "hello?"), kDefaultTimeout);
ASSERT_TRUE(SendData(transport2(), 2, "hi transport1", &result));
EXPECT_EQ(SDR_SUCCESS, result);
EXPECT_TRUE_WAIT(ReceivedData(receiver1(), 2, "hi transport1"),
kDefaultTimeout);
// Close two streams on one side.
transport2()->ResetStream(2);
transport2()->ResetStream(3);
EXPECT_TRUE_WAIT(transport2_observer.WasStreamClosed(2), kDefaultTimeout);
EXPECT_TRUE_WAIT(transport2_observer.WasStreamClosed(3), kDefaultTimeout);
}
TEST_F(SctpTransportTest, ClosesStreamsOnBothSides) {
SetupConnectedTransportsWithTwoStreams();
AddStream(3);
AddStream(4);
SctpTransportObserver transport1_observer(transport1());
SctpTransportObserver transport2_observer(transport2());
SendDataResult result;
ASSERT_TRUE(SendData(transport1(), 1, "hello?", &result));
EXPECT_EQ(SDR_SUCCESS, result);
EXPECT_TRUE_WAIT(ReceivedData(receiver2(), 1, "hello?"), kDefaultTimeout);
ASSERT_TRUE(SendData(transport2(), 2, "hi transport1", &result));
EXPECT_EQ(SDR_SUCCESS, result);
EXPECT_TRUE_WAIT(ReceivedData(receiver1(), 2, "hi transport1"),
kDefaultTimeout);
// Close one stream on transport1(), while closing three streams on
// transport2(). They will conflict (only one side can close anything at a
// time, apparently). Test the resolution of the conflict.
transport1()->ResetStream(1);
transport2()->ResetStream(2);
transport2()->ResetStream(3);
transport2()->ResetStream(4);
EXPECT_TRUE_WAIT(transport2_observer.WasStreamClosed(1), kDefaultTimeout);
EXPECT_TRUE_WAIT(transport1_observer.WasStreamClosed(2), kDefaultTimeout);
EXPECT_TRUE_WAIT(transport1_observer.WasStreamClosed(3), kDefaultTimeout);
EXPECT_TRUE_WAIT(transport1_observer.WasStreamClosed(4), kDefaultTimeout);
}
TEST_F(SctpTransportTest, RefusesHighNumberedTransports) {
SetupConnectedTransportsWithTwoStreams();
EXPECT_TRUE(AddStream(kMaxSctpSid));
EXPECT_FALSE(AddStream(kMaxSctpSid + 1));
}
TEST_F(SctpTransportTest, ReusesAStream) {
// Shut down transport 1, then open it up again for reuse.
SetupConnectedTransportsWithTwoStreams();
SendDataResult result;
SctpTransportObserver transport2_observer(transport2());
ASSERT_TRUE(SendData(transport1(), 1, "hello?", &result));
EXPECT_EQ(SDR_SUCCESS, result);
EXPECT_TRUE_WAIT(ReceivedData(receiver2(), 1, "hello?"), kDefaultTimeout);
transport1()->ResetStream(1);
EXPECT_TRUE_WAIT(transport2_observer.WasStreamClosed(1), kDefaultTimeout);
// Transport 1 is gone now.
// Create a new transport 1.
AddStream(1);
ASSERT_TRUE(SendData(transport1(), 1, "hi?", &result));
EXPECT_EQ(SDR_SUCCESS, result);
EXPECT_TRUE_WAIT(ReceivedData(receiver2(), 1, "hi?"), kDefaultTimeout);
transport1()->ResetStream(1);
EXPECT_EQ_WAIT(2, transport2_observer.StreamCloseCount(1), kDefaultTimeout);
}
TEST_F(SctpTransportTest, RejectsTooLargeMessageSize) {
FakeDtlsTransport fake_dtls("fake dtls", 0);
SctpFakeDataReceiver recv;
std::unique_ptr<SctpTransport> transport(CreateTransport(&fake_dtls, &recv));
EXPECT_FALSE(transport->Start(kSctpDefaultPort, kSctpDefaultPort,
kSctpSendBufferSize + 1));
}
TEST_F(SctpTransportTest, RejectsTooSmallMessageSize) {
FakeDtlsTransport fake_dtls("fake dtls", 0);
SctpFakeDataReceiver recv;
std::unique_ptr<SctpTransport> transport(CreateTransport(&fake_dtls, &recv));
EXPECT_FALSE(transport->Start(kSctpDefaultPort, kSctpDefaultPort, 0));
}
TEST_F(SctpTransportTest, RejectsSendTooLargeMessages) {
SetupConnectedTransportsWithTwoStreams();
// Use "Start" to reduce the max message size
transport1()->Start(kTransport1Port, kTransport2Port, 10);
EXPECT_EQ(10, transport1()->max_message_size());
const char eleven_characters[] = "12345678901";
SendDataResult result;
EXPECT_FALSE(SendData(transport1(), 1, eleven_characters, &result));
}
} // namespace cricket