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/*
* Copyright 2012 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 "examples/peerconnection/client/peer_connection_client.h"
#include "api/units/time_delta.h"
#include "examples/peerconnection/client/defaults.h"
#include "rtc_base/async_dns_resolver.h"
#include "rtc_base/checks.h"
#include "rtc_base/logging.h"
#include "rtc_base/net_helpers.h"
#include "rtc_base/thread.h"
namespace {
// This is our magical hangup signal.
constexpr char kByeMessage[] = "BYE";
// Delay between server connection retries, in milliseconds
constexpr webrtc::TimeDelta kReconnectDelay = webrtc::TimeDelta::Seconds(2);
rtc::Socket* CreateClientSocket(int family) {
rtc::Thread* thread = rtc::Thread::Current();
RTC_DCHECK(thread != NULL);
return thread->socketserver()->CreateSocket(family, SOCK_STREAM);
}
} // namespace
PeerConnectionClient::PeerConnectionClient()
: callback_(NULL), resolver_(nullptr), state_(NOT_CONNECTED), my_id_(-1) {}
PeerConnectionClient::~PeerConnectionClient() = default;
void PeerConnectionClient::InitSocketSignals() {
RTC_DCHECK(control_socket_.get() != NULL);
RTC_DCHECK(hanging_get_.get() != NULL);
control_socket_->SignalCloseEvent.connect(this,
&PeerConnectionClient::OnClose);
hanging_get_->SignalCloseEvent.connect(this, &PeerConnectionClient::OnClose);
control_socket_->SignalConnectEvent.connect(this,
&PeerConnectionClient::OnConnect);
hanging_get_->SignalConnectEvent.connect(
this, &PeerConnectionClient::OnHangingGetConnect);
control_socket_->SignalReadEvent.connect(this, &PeerConnectionClient::OnRead);
hanging_get_->SignalReadEvent.connect(
this, &PeerConnectionClient::OnHangingGetRead);
}
int PeerConnectionClient::id() const {
return my_id_;
}
bool PeerConnectionClient::is_connected() const {
return my_id_ != -1;
}
const Peers& PeerConnectionClient::peers() const {
return peers_;
}
void PeerConnectionClient::RegisterObserver(
PeerConnectionClientObserver* callback) {
RTC_DCHECK(!callback_);
callback_ = callback;
}
void PeerConnectionClient::Connect(const std::string& server,
int port,
const std::string& client_name) {
RTC_DCHECK(!server.empty());
RTC_DCHECK(!client_name.empty());
if (state_ != NOT_CONNECTED) {
RTC_LOG(LS_WARNING)
<< "The client must not be connected before you can call Connect()";
callback_->OnServerConnectionFailure();
return;
}
if (server.empty() || client_name.empty()) {
callback_->OnServerConnectionFailure();
return;
}
if (port <= 0)
port = kDefaultServerPort;
server_address_.SetIP(server);
server_address_.SetPort(port);
client_name_ = client_name;
if (server_address_.IsUnresolvedIP()) {
RTC_DCHECK_NE(state_, RESOLVING);
RTC_DCHECK(!resolver_);
state_ = RESOLVING;
resolver_ = std::make_unique<webrtc::AsyncDnsResolver>();
resolver_->Start(server_address_,
[this] { OnResolveResult(resolver_->result()); });
} else {
DoConnect();
}
}
void PeerConnectionClient::OnResolveResult(
const webrtc::AsyncDnsResolverResult& result) {
if (result.GetError() != 0) {
callback_->OnServerConnectionFailure();
resolver_.reset();
state_ = NOT_CONNECTED;
return;
}
if (!result.GetResolvedAddress(AF_INET, &server_address_)) {
callback_->OnServerConnectionFailure();
resolver_.reset();
state_ = NOT_CONNECTED;
return;
}
DoConnect();
}
void PeerConnectionClient::DoConnect() {
control_socket_.reset(CreateClientSocket(server_address_.ipaddr().family()));
hanging_get_.reset(CreateClientSocket(server_address_.ipaddr().family()));
InitSocketSignals();
char buffer[1024];
snprintf(buffer, sizeof(buffer), "GET /sign_in?%s HTTP/1.0\r\n\r\n",
client_name_.c_str());
onconnect_data_ = buffer;
bool ret = ConnectControlSocket();
if (ret)
state_ = SIGNING_IN;
if (!ret) {
callback_->OnServerConnectionFailure();
}
}
bool PeerConnectionClient::SendToPeer(int peer_id, const std::string& message) {
if (state_ != CONNECTED)
return false;
RTC_DCHECK(is_connected());
RTC_DCHECK(control_socket_->GetState() == rtc::Socket::CS_CLOSED);
if (!is_connected() || peer_id == -1)
return false;
char headers[1024];
snprintf(headers, sizeof(headers),
"POST /message?peer_id=%i&to=%i HTTP/1.0\r\n"
"Content-Length: %zu\r\n"
"Content-Type: text/plain\r\n"
"\r\n",
my_id_, peer_id, message.length());
onconnect_data_ = headers;
onconnect_data_ += message;
return ConnectControlSocket();
}
bool PeerConnectionClient::SendHangUp(int peer_id) {
return SendToPeer(peer_id, kByeMessage);
}
bool PeerConnectionClient::IsSendingMessage() {
return state_ == CONNECTED &&
control_socket_->GetState() != rtc::Socket::CS_CLOSED;
}
bool PeerConnectionClient::SignOut() {
if (state_ == NOT_CONNECTED || state_ == SIGNING_OUT)
return true;
if (hanging_get_->GetState() != rtc::Socket::CS_CLOSED)
hanging_get_->Close();
if (control_socket_->GetState() == rtc::Socket::CS_CLOSED) {
state_ = SIGNING_OUT;
if (my_id_ != -1) {
char buffer[1024];
snprintf(buffer, sizeof(buffer),
"GET /sign_out?peer_id=%i HTTP/1.0\r\n\r\n", my_id_);
onconnect_data_ = buffer;
return ConnectControlSocket();
} else {
// Can occur if the app is closed before we finish connecting.
return true;
}
} else {
state_ = SIGNING_OUT_WAITING;
}
return true;
}
void PeerConnectionClient::Close() {
control_socket_->Close();
hanging_get_->Close();
onconnect_data_.clear();
peers_.clear();
resolver_.reset();
my_id_ = -1;
state_ = NOT_CONNECTED;
}
bool PeerConnectionClient::ConnectControlSocket() {
RTC_DCHECK(control_socket_->GetState() == rtc::Socket::CS_CLOSED);
int err = control_socket_->Connect(server_address_);
if (err == SOCKET_ERROR) {
Close();
return false;
}
return true;
}
void PeerConnectionClient::OnConnect(rtc::Socket* socket) {
RTC_DCHECK(!onconnect_data_.empty());
size_t sent = socket->Send(onconnect_data_.c_str(), onconnect_data_.length());
RTC_DCHECK(sent == onconnect_data_.length());
onconnect_data_.clear();
}
void PeerConnectionClient::OnHangingGetConnect(rtc::Socket* socket) {
char buffer[1024];
snprintf(buffer, sizeof(buffer), "GET /wait?peer_id=%i HTTP/1.0\r\n\r\n",
my_id_);
int len = static_cast<int>(strlen(buffer));
int sent = socket->Send(buffer, len);
RTC_DCHECK(sent == len);
}
void PeerConnectionClient::OnMessageFromPeer(int peer_id,
const std::string& message) {
if (message.length() == (sizeof(kByeMessage) - 1) &&
message.compare(kByeMessage) == 0) {
callback_->OnPeerDisconnected(peer_id);
} else {
callback_->OnMessageFromPeer(peer_id, message);
}
}
bool PeerConnectionClient::GetHeaderValue(const std::string& data,
size_t eoh,
const char* header_pattern,
size_t* value) {
RTC_DCHECK(value != NULL);
size_t found = data.find(header_pattern);
if (found != std::string::npos && found < eoh) {
*value = atoi(&data[found + strlen(header_pattern)]);
return true;
}
return false;
}
bool PeerConnectionClient::GetHeaderValue(const std::string& data,
size_t eoh,
const char* header_pattern,
std::string* value) {
RTC_DCHECK(value != NULL);
size_t found = data.find(header_pattern);
if (found != std::string::npos && found < eoh) {
size_t begin = found + strlen(header_pattern);
size_t end = data.find("\r\n", begin);
if (end == std::string::npos)
end = eoh;
value->assign(data.substr(begin, end - begin));
return true;
}
return false;
}
bool PeerConnectionClient::ReadIntoBuffer(rtc::Socket* socket,
std::string* data,
size_t* content_length) {
char buffer[0xffff];
do {
int bytes = socket->Recv(buffer, sizeof(buffer), nullptr);
if (bytes <= 0)
break;
data->append(buffer, bytes);
} while (true);
bool ret = false;
size_t i = data->find("\r\n\r\n");
if (i != std::string::npos) {
RTC_LOG(LS_INFO) << "Headers received";
if (GetHeaderValue(*data, i, "\r\nContent-Length: ", content_length)) {
size_t total_response_size = (i + 4) + *content_length;
if (data->length() >= total_response_size) {
ret = true;
std::string should_close;
const char kConnection[] = "\r\nConnection: ";
if (GetHeaderValue(*data, i, kConnection, &should_close) &&
should_close.compare("close") == 0) {
socket->Close();
// Since we closed the socket, there was no notification delivered
// to us. Compensate by letting ourselves know.
OnClose(socket, 0);
}
} else {
// We haven't received everything. Just continue to accept data.
}
} else {
RTC_LOG(LS_ERROR) << "No content length field specified by the server.";
}
}
return ret;
}
void PeerConnectionClient::OnRead(rtc::Socket* socket) {
size_t content_length = 0;
if (ReadIntoBuffer(socket, &control_data_, &content_length)) {
size_t peer_id = 0, eoh = 0;
bool ok =
ParseServerResponse(control_data_, content_length, &peer_id, &eoh);
if (ok) {
if (my_id_ == -1) {
// First response. Let's store our server assigned ID.
RTC_DCHECK(state_ == SIGNING_IN);
my_id_ = static_cast<int>(peer_id);
RTC_DCHECK(my_id_ != -1);
// The body of the response will be a list of already connected peers.
if (content_length) {
size_t pos = eoh + 4;
while (pos < control_data_.size()) {
size_t eol = control_data_.find('\n', pos);
if (eol == std::string::npos)
break;
int id = 0;
std::string name;
bool connected;
if (ParseEntry(control_data_.substr(pos, eol - pos), &name, &id,
&connected) &&
id != my_id_) {
peers_[id] = name;
callback_->OnPeerConnected(id, name);
}
pos = eol + 1;
}
}
RTC_DCHECK(is_connected());
callback_->OnSignedIn();
} else if (state_ == SIGNING_OUT) {
Close();
callback_->OnDisconnected();
} else if (state_ == SIGNING_OUT_WAITING) {
SignOut();
}
}
control_data_.clear();
if (state_ == SIGNING_IN) {
RTC_DCHECK(hanging_get_->GetState() == rtc::Socket::CS_CLOSED);
state_ = CONNECTED;
hanging_get_->Connect(server_address_);
}
}
}
void PeerConnectionClient::OnHangingGetRead(rtc::Socket* socket) {
RTC_LOG(LS_INFO) << __FUNCTION__;
size_t content_length = 0;
if (ReadIntoBuffer(socket, ¬ification_data_, &content_length)) {
size_t peer_id = 0, eoh = 0;
bool ok =
ParseServerResponse(notification_data_, content_length, &peer_id, &eoh);
if (ok) {
// Store the position where the body begins.
size_t pos = eoh + 4;
if (my_id_ == static_cast<int>(peer_id)) {
// A notification about a new member or a member that just
// disconnected.
int id = 0;
std::string name;
bool connected = false;
if (ParseEntry(notification_data_.substr(pos), &name, &id,
&connected)) {
if (connected) {
peers_[id] = name;
callback_->OnPeerConnected(id, name);
} else {
peers_.erase(id);
callback_->OnPeerDisconnected(id);
}
}
} else {
OnMessageFromPeer(static_cast<int>(peer_id),
notification_data_.substr(pos));
}
}
notification_data_.clear();
}
if (hanging_get_->GetState() == rtc::Socket::CS_CLOSED &&
state_ == CONNECTED) {
hanging_get_->Connect(server_address_);
}
}
bool PeerConnectionClient::ParseEntry(const std::string& entry,
std::string* name,
int* id,
bool* connected) {
RTC_DCHECK(name != NULL);
RTC_DCHECK(id != NULL);
RTC_DCHECK(connected != NULL);
RTC_DCHECK(!entry.empty());
*connected = false;
size_t separator = entry.find(',');
if (separator != std::string::npos) {
*id = atoi(&entry[separator + 1]);
name->assign(entry.substr(0, separator));
separator = entry.find(',', separator + 1);
if (separator != std::string::npos) {
*connected = atoi(&entry[separator + 1]) ? true : false;
}
}
return !name->empty();
}
int PeerConnectionClient::GetResponseStatus(const std::string& response) {
int status = -1;
size_t pos = response.find(' ');
if (pos != std::string::npos)
status = atoi(&response[pos + 1]);
return status;
}
bool PeerConnectionClient::ParseServerResponse(const std::string& response,
size_t content_length,
size_t* peer_id,
size_t* eoh) {
int status = GetResponseStatus(response.c_str());
if (status != 200) {
RTC_LOG(LS_ERROR) << "Received error from server";
Close();
callback_->OnDisconnected();
return false;
}
*eoh = response.find("\r\n\r\n");
RTC_DCHECK(*eoh != std::string::npos);
if (*eoh == std::string::npos)
return false;
*peer_id = -1;
// See comment in peer_channel.cc for why we use the Pragma header.
GetHeaderValue(response, *eoh, "\r\nPragma: ", peer_id);
return true;
}
void PeerConnectionClient::OnClose(rtc::Socket* socket, int err) {
RTC_LOG(LS_INFO) << __FUNCTION__;
socket->Close();
#ifdef WIN32
if (err != WSAECONNREFUSED) {
#else
if (err != ECONNREFUSED) {
#endif
if (socket == hanging_get_.get()) {
if (state_ == CONNECTED) {
hanging_get_->Close();
hanging_get_->Connect(server_address_);
}
} else {
callback_->OnMessageSent(err);
}
} else {
if (socket == control_socket_.get()) {
RTC_LOG(LS_WARNING) << "Connection refused; retrying in 2 seconds";
rtc::Thread::Current()->PostDelayedTask(
SafeTask(safety_.flag(), [this] { DoConnect(); }), kReconnectDelay);
} else {
Close();
callback_->OnDisconnected();
}
}
}