examples/peerconnection/client/peer_connection_client.cc - src.git - Git at Google

 /*
  *  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 "examples/peerconnection/client/defaults.h"
 #include "rtc_base/checks.h"
 #include "rtc_base/logging.h"
 #include "rtc_base/nethelpers.h"
 #include "rtc_base/stringutils.h"

 #ifdef WIN32
 #include "rtc_base/win32socketserver.h"
 #endif

 using rtc::sprintfn;

 namespace {

 // This is our magical hangup signal.
 const char kByeMessage[] = "BYE";
 // Delay between server connection retries, in milliseconds
 const int kReconnectDelay = 2000;

 rtc::AsyncSocket* CreateClientSocket(int family) {
 #ifdef WIN32
   rtc::Win32Socket* sock = new rtc::Win32Socket();
   sock->CreateT(family, SOCK_STREAM);
   return sock;
 #elif defined(WEBRTC_POSIX)
   rtc::Thread* thread = rtc::Thread::Current();
   RTC_DCHECK(thread != NULL);
   return thread->socketserver()->CreateAsyncSocket(family, SOCK_STREAM);
 #else
 #error Platform not supported.
 #endif
 }

 }  // namespace

 PeerConnectionClient::PeerConnectionClient()
     : callback_(NULL), resolver_(NULL), state_(NOT_CONNECTED), my_id_(-1) {}

 PeerConnectionClient::~PeerConnectionClient() {}

 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(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()) {
     state_ = RESOLVING;
     resolver_ = new rtc::AsyncResolver();
     resolver_->SignalDone.connect(this, &PeerConnectionClient::OnResolveResult);
     resolver_->Start(server_address_);
   } else {
     DoConnect();
   }
 }

 void PeerConnectionClient::OnResolveResult(
     rtc::AsyncResolverInterface* resolver) {
   if (resolver_->GetError() != 0) {
     callback_->OnServerConnectionFailure();
     resolver_->Destroy(false);
     resolver_ = NULL;
     state_ = NOT_CONNECTED;
   } else {
     server_address_ = resolver_->address();
     DoConnect();
   }
 }

 void PeerConnectionClient::DoConnect() {
   control_socket_.reset(CreateClientSocket(server_address_.ipaddr().family()));
   hanging_get_.reset(CreateClientSocket(server_address_.ipaddr().family()));
   InitSocketSignals();
   char buffer[1024];
   sprintfn(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];
   sprintfn(headers, sizeof(headers),
            "POST /message?peer_id=%i&to=%i HTTP/1.0\r\n"
            "Content-Length: %i\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];
       sprintfn(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();
   if (resolver_ != NULL) {
     resolver_->Destroy(false);
     resolver_ = NULL;
   }
   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::AsyncSocket* 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::AsyncSocket* socket) {
   char buffer[1024];
   sprintfn(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::AsyncSocket* 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(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::AsyncSocket* 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::AsyncSocket* socket) {
   RTC_LOG(INFO) << __FUNCTION__;
   size_t content_length = 0;
   if (ReadIntoBuffer(socket, &notification_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 and
   // not e.g. "X-Peer-Id".
   GetHeaderValue(response, *eoh, "\r\nPragma: ", peer_id);

   return true;
 }

 void PeerConnectionClient::OnClose(rtc::AsyncSocket* socket, int err) {
   RTC_LOG(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(WARNING) << "Connection refused; retrying in 2 seconds";
       rtc::Thread::Current()->PostDelayed(RTC_FROM_HERE, kReconnectDelay, this,
                                           0);
     } else {
       Close();
       callback_->OnDisconnected();
     }
   }
 }

 void PeerConnectionClient::OnMessage(rtc::Message* msg) {
   // ignore msg; there is currently only one supported message ("retry")
   DoConnect();
 }
	/*
	* 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 "examples/peerconnection/client/defaults.h"
	#include "rtc_base/checks.h"
	#include "rtc_base/logging.h"
	#include "rtc_base/nethelpers.h"
	#include "rtc_base/stringutils.h"

	#ifdef WIN32
	#include "rtc_base/win32socketserver.h"
	#endif

	using rtc::sprintfn;

	namespace {

	// This is our magical hangup signal.
	const char kByeMessage[] = "BYE";
	// Delay between server connection retries, in milliseconds
	const int kReconnectDelay = 2000;

	rtc::AsyncSocket* CreateClientSocket(int family) {
	#ifdef WIN32
	rtc::Win32Socket* sock = new rtc::Win32Socket();
	sock->CreateT(family, SOCK_STREAM);
	return sock;
	#elif defined(WEBRTC_POSIX)
	rtc::Thread* thread = rtc::Thread::Current();
	RTC_DCHECK(thread != NULL);
	return thread->socketserver()->CreateAsyncSocket(family, SOCK_STREAM);
	#else
	#error Platform not supported.
	#endif
	}

	} // namespace

	PeerConnectionClient::PeerConnectionClient()
	: callback_(NULL), resolver_(NULL), state_(NOT_CONNECTED), my_id_(-1) {}

	PeerConnectionClient::~PeerConnectionClient() {}

	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(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()) {
	state_ = RESOLVING;
	resolver_ = new rtc::AsyncResolver();
	resolver_->SignalDone.connect(this, &PeerConnectionClient::OnResolveResult);
	resolver_->Start(server_address_);
	} else {
	DoConnect();
	}
	}

	void PeerConnectionClient::OnResolveResult(
	rtc::AsyncResolverInterface* resolver) {
	if (resolver_->GetError() != 0) {
	callback_->OnServerConnectionFailure();
	resolver_->Destroy(false);
	resolver_ = NULL;
	state_ = NOT_CONNECTED;
	} else {
	server_address_ = resolver_->address();
	DoConnect();
	}
	}

	void PeerConnectionClient::DoConnect() {
	control_socket_.reset(CreateClientSocket(server_address_.ipaddr().family()));
	hanging_get_.reset(CreateClientSocket(server_address_.ipaddr().family()));
	InitSocketSignals();
	char buffer[1024];
	sprintfn(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];
	sprintfn(headers, sizeof(headers),
	"POST /message?peer_id=%i&to=%i HTTP/1.0\r\n"
	"Content-Length: %i\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];
	sprintfn(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();
	if (resolver_ != NULL) {
	resolver_->Destroy(false);
	resolver_ = NULL;
	}
	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::AsyncSocket* 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::AsyncSocket* socket) {
	char buffer[1024];
	sprintfn(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::AsyncSocket* 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(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::AsyncSocket* 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::AsyncSocket* socket) {
	RTC_LOG(INFO) << __FUNCTION__;
	size_t content_length = 0;
	if (ReadIntoBuffer(socket, &notification_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 and
	// not e.g. "X-Peer-Id".
	GetHeaderValue(response, *eoh, "\r\nPragma: ", peer_id);

	return true;
	}

	void PeerConnectionClient::OnClose(rtc::AsyncSocket* socket, int err) {
	RTC_LOG(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(WARNING) << "Connection refused; retrying in 2 seconds";
	rtc::Thread::Current()->PostDelayed(RTC_FROM_HERE, kReconnectDelay, this,
	0);
	} else {
	Close();
	callback_->OnDisconnected();
	}
	}
	}

	void PeerConnectionClient::OnMessage(rtc::Message* msg) {
	// ignore msg; there is currently only one supported message ("retry")
	DoConnect();
	}