aboutsummaryrefslogtreecommitdiff
path: root/assets/blender/trackplane.blend
Commit message (Expand)AuthorAge
* Restructure mod directoryorwell962017-01-04
36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841
/*
Minetest
Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/

#pragma once

#include "irrlichttypes_bloated.h"
#include "peerhandler.h"
#include "socket.h"
#include "constants.h"
#include "util/pointer.h"
#include "util/container.h"
#include "util/thread.h"
#include "util/numeric.h"
#include "networkprotocol.h"
#include <iostream>
#include <fstream>
#include <vector>
#include <map>

class NetworkPacket;

namespace con
{

class ConnectionReceiveThread;
class ConnectionSendThread;

typedef enum MTProtocols {
	MTP_PRIMARY,
	MTP_UDP,
	MTP_MINETEST_RELIABLE_UDP
} MTProtocols;

#define MAX_UDP_PEERS 65535

#define SEQNUM_MAX 65535

inline bool seqnum_higher(u16 totest, u16 base)
{
	if (totest > base)
	{
		if ((totest - base) > (SEQNUM_MAX/2))
			return false;

		return true;
	}

	if ((base - totest) > (SEQNUM_MAX/2))
		return true;

	return false;
}

inline bool seqnum_in_window(u16 seqnum, u16 next,u16 window_size)
{
	u16 window_start = next;
	u16 window_end   = ( next + window_size ) % (SEQNUM_MAX+1);

	if (window_start < window_end) {
		return ((seqnum >= window_start) && (seqnum < window_end));
	}


	return ((seqnum < window_end) || (seqnum >= window_start));
}

static inline float CALC_DTIME(u64 lasttime, u64 curtime)
{
	float value = ( curtime - lasttime) / 1000.0;
	return MYMAX(MYMIN(value,0.1),0.0);
}

struct BufferedPacket
{
	BufferedPacket(u8 *a_data, u32 a_size):
		data(a_data, a_size)
	{}
	BufferedPacket(u32 a_size):
		data(a_size)
	{}
	Buffer<u8> data; // Data of the packet, including headers
	float time = 0.0f; // Seconds from buffering the packet or re-sending
	float totaltime = 0.0f; // Seconds from buffering the packet
	u64 absolute_send_time = -1;
	Address address; // Sender or destination
	unsigned int resend_count = 0;
};

// This adds the base headers to the data and makes a packet out of it
BufferedPacket makePacket(Address &address, const SharedBuffer<u8> &data,
		u32 protocol_id, session_t sender_peer_id, u8 channel);

// Depending on size, make a TYPE_ORIGINAL or TYPE_SPLIT packet
// Increments split_seqnum if a split packet is made
void makeAutoSplitPacket(const SharedBuffer<u8> &data, u32 chunksize_max,
		u16 &split_seqnum, std::list<SharedBuffer<u8>> *list);

// Add the TYPE_RELIABLE header to the data
SharedBuffer<u8> makeReliablePacket(const SharedBuffer<u8> &data, u16 seqnum);

struct IncomingSplitPacket
{
	IncomingSplitPacket(u32 cc, bool r):
		chunk_count(cc), reliable(r) {}

	IncomingSplitPacket() = delete;

	float time = 0.0f; // Seconds from adding
	u32 chunk_count;
	bool reliable; // If true, isn't deleted on timeout

	bool allReceived() const
	{
		return (chunks.size() == chunk_count);
	}
	bool insert(u32 chunk_num, SharedBuffer<u8> &chunkdata);
	SharedBuffer<u8> reassemble();

private:
	// Key is chunk number, value is data without headers
	std::map<u16, SharedBuffer<u8>> chunks;
};

/*
=== NOTES ===

A packet is sent through a channel to a peer with a basic header:
	Header (7 bytes):
	[0] u32 protocol_id
	[4] session_t sender_peer_id
	[6] u8 channel
sender_peer_id:
	Unique to each peer.
	value 0 (PEER_ID_INEXISTENT) is reserved for making new connections
	value 1 (PEER_ID_SERVER) is reserved for server
	these constants are defined in constants.h
channel:
	Channel numbers have no intrinsic meaning. Currently only 0, 1, 2 exist.
*/
#define BASE_HEADER_SIZE 7
#define CHANNEL_COUNT 3
/*
Packet types:

CONTROL: This is a packet used by the protocol.
- When this is processed, nothing is handed to the user.
	Header (2 byte):
	[0] u8 type
	[1] u8 controltype
controltype and data description:
	CONTROLTYPE_ACK
		[2] u16 seqnum
	CONTROLTYPE_SET_PEER_ID
		[2] session_t peer_id_new
	CONTROLTYPE_PING
	- There is no actual reply, but this can be sent in a reliable
	  packet to get a reply
	CONTROLTYPE_DISCO
*/
//#define TYPE_CONTROL 0
#define CONTROLTYPE_ACK 0
#define CONTROLTYPE_SET_PEER_ID 1
#define CONTROLTYPE_PING 2
#define CONTROLTYPE_DISCO 3

/*
ORIGINAL: This is a plain packet with no control and no error
checking at all.
- When this is processed, it is directly handed to the user.
	Header (1 byte):
	[0] u8 type
*/
//#define TYPE_ORIGINAL 1
#define ORIGINAL_HEADER_SIZE 1
/*
SPLIT: These are sequences of packets forming one bigger piece of
data.
- When processed and all the packet_nums 0...packet_count-1 are
  present (this should be buffered), the resulting data shall be
  directly handed to the user.
- If the data fails to come up in a reasonable time, the buffer shall
  be silently discarded.
- These can be sent as-is or atop of a RELIABLE packet stream.
	Header (7 bytes):
	[0] u8 type
	[1] u16 seqnum
	[3] u16 chunk_count
	[5] u16 chunk_num
*/
//#define TYPE_SPLIT 2
/*
RELIABLE: Delivery of all RELIABLE packets shall be forced by ACKs,
and they shall be delivered in the same order as sent. This is done
with a buffer in the receiving and transmitting end.
- When this is processed, the contents of each packet is recursively
  processed as packets.
	Header (3 bytes):
	[0] u8 type
	[1] u16 seqnum

*/
//#define TYPE_RELIABLE 3
#define RELIABLE_HEADER_SIZE 3
#define SEQNUM_INITIAL 65500

enum PacketType: u8 {
	PACKET_TYPE_CONTROL = 0,
	PACKET_TYPE_ORIGINAL = 1,
	PACKET_TYPE_SPLIT = 2,
	PACKET_TYPE_RELIABLE = 3,
	PACKET_TYPE_MAX
};
/*
	A buffer which stores reliable packets and sorts them internally
	for fast access to the smallest one.
*/

typedef std::list<BufferedPacket>::iterator RPBSearchResult;

class ReliablePacketBuffer
{
public:
	ReliablePacketBuffer() = default;

	bool getFirstSeqnum(u16& result);

	BufferedPacket popFirst();
	BufferedPacket popSeqnum(u16 seqnum);
	void insert(BufferedPacket &p, u16 next_expected);

	void incrementTimeouts(float dtime);
	std::list<BufferedPacket> getTimedOuts(float timeout,
			unsigned int max_packets);

	void print();
	bool empty();
	RPBSearchResult notFound();
	u32 size();


private:
	RPBSearchResult findPacket(u16 seqnum); // does not perform locking

	std::list<BufferedPacket> m_list;

	u16 m_oldest_non_answered_ack;

	std::mutex m_list_mutex;
};

/*
	A buffer for reconstructing split packets
*/

class IncomingSplitBuffer
{
public:
	~IncomingSplitBuffer();
	/*
		Returns a reference counted buffer of length != 0 when a full split
		packet is constructed. If not, returns one of length 0.
	*/
	SharedBuffer<u8> insert(const BufferedPacket &p, bool reliable);

	void removeUnreliableTimedOuts(float dtime, float timeout);

private:
	// Key is seqnum
	std::map<u16, IncomingSplitPacket*> m_buf;

	std::mutex m_map_mutex;
};

struct OutgoingPacket
{
	session_t peer_id;
	u8 channelnum;
	SharedBuffer<u8> data;
	bool reliable;
	bool ack;

	OutgoingPacket(session_t peer_id_, u8 channelnum_, const SharedBuffer<u8> &data_,
			bool reliable_,bool ack_=false):
		peer_id(peer_id_),
		channelnum(channelnum_),
		data(data_),
		reliable(reliable_),
		ack(ack_)
	{
	}
};

enum ConnectionCommandType{
	CONNCMD_NONE,
	CONNCMD_SERVE,
	CONNCMD_CONNECT,
	CONNCMD_DISCONNECT,
	CONNCMD_DISCONNECT_PEER,
	CONNCMD_SEND,
	CONNCMD_SEND_TO_ALL,
	CONCMD_ACK,
	CONCMD_CREATE_PEER
};

struct ConnectionCommand
{
	enum ConnectionCommandType type = CONNCMD_NONE;
	Address address;
	session_t peer_id = PEER_ID_INEXISTENT;
	u8 channelnum = 0;
	Buffer<u8> data;
	bool reliable = false;
	bool raw = false;

	ConnectionCommand() = default;
	ConnectionCommand &operator=(const ConnectionCommand &other)
	{
		type = other.type;
		address = other.address;
		peer_id = other.peer_id;
		channelnum = other.channelnum;
		// We must copy the buffer here to prevent race condition
		data = SharedBuffer<u8>(*other.data, other.data.getSize());
		reliable = other.reliable;
		raw = other.raw;
		return *this;
	}

	void serve(Address address_)
	{
		type = CONNCMD_SERVE;
		address = address_;
	}
	void connect(Address address_)
	{
		type = CONNCMD_CONNECT;
		address = address_;
	}
	void disconnect()
	{
		type = CONNCMD_DISCONNECT;
	}
	void disconnect_peer(session_t peer_id_)
	{
		type = CONNCMD_DISCONNECT_PEER;
		peer_id = peer_id_;
	}

	void send(session_t peer_id_, u8 channelnum_, NetworkPacket *pkt, bool reliable_);

	void ack(session_t peer_id_, u8 channelnum_, const SharedBuffer<u8> &data_)
	{
		type = CONCMD_ACK;
		peer_id = peer_id_;
		channelnum = channelnum_;
		data = data_;
		reliable = false;
	}

	void createPeer(session_t peer_id_, const SharedBuffer<u8> &data_)
	{
		type = CONCMD_CREATE_PEER;
		peer_id = peer_id_;
		data = data_;
		channelnum = 0;
		reliable = true;
		raw = true;
	}
};

/* maximum window size to use, 0xFFFF is theoretical maximum. don't think about
 * touching it, the less you're away from it the more likely data corruption
 * will occur
 */
#define MAX_RELIABLE_WINDOW_SIZE 0x8000
/* starting value for window size */
#define START_RELIABLE_WINDOW_SIZE 0x400
/* minimum value for window size */
#define MIN_RELIABLE_WINDOW_SIZE 0x40

class Channel
{

public:
	u16 readNextIncomingSeqNum();
	u16 incNextIncomingSeqNum();

	u16 getOutgoingSequenceNumber(bool& successfull);
	u16 readOutgoingSequenceNumber();
	bool putBackSequenceNumber(u16);

	u16 readNextSplitSeqNum();
	void setNextSplitSeqNum(u16 seqnum);

	// This is for buffering the incoming packets that are coming in
	// the wrong order
	ReliablePacketBuffer incoming_reliables;
	// This is for buffering the sent packets so that the sender can
	// re-send them if no ACK is received
	ReliablePacketBuffer outgoing_reliables_sent;

	//queued reliable packets
	std::queue<BufferedPacket> queued_reliables;

	//queue commands prior splitting to packets
	std::deque<ConnectionCommand> queued_commands;

	IncomingSplitBuffer incoming_splits;

	Channel() = default;
	~Channel() = default;

	void UpdatePacketLossCounter(unsigned int count);
	void UpdatePacketTooLateCounter();
	void UpdateBytesSent(unsigned int bytes,unsigned int packages=1);
	void UpdateBytesLost(unsigned int bytes);
	void UpdateBytesReceived(unsigned int bytes);

	void UpdateTimers(float dtime);

	const float getCurrentDownloadRateKB()
		{ MutexAutoLock lock(m_internal_mutex); return cur_kbps; };
	const float getMaxDownloadRateKB()
		{ MutexAutoLock lock(m_internal_mutex); return max_kbps; };

	const float getCurrentLossRateKB()
		{ MutexAutoLock lock(m_internal_mutex); return cur_kbps_lost; };
	const float getMaxLossRateKB()
		{ MutexAutoLock lock(m_internal_mutex); return max_kbps_lost; };

	const float getCurrentIncomingRateKB()
		{ MutexAutoLock lock(m_internal_mutex); return cur_incoming_kbps; };
	const float getMaxIncomingRateKB()
		{ MutexAutoLock lock(m_internal_mutex); return max_incoming_kbps; };

	const float getAvgDownloadRateKB()
		{ MutexAutoLock lock(m_internal_mutex); return avg_kbps; };
	const float getAvgLossRateKB()
		{ MutexAutoLock lock(m_internal_mutex); return avg_kbps_lost; };
	const float getAvgIncomingRateKB()
		{ MutexAutoLock lock(m_internal_mutex); return avg_incoming_kbps; };

	const unsigned int getWindowSize() const { return window_size; };

	void setWindowSize(unsigned int size) { window_size = size; };
private:
	std::mutex m_internal_mutex;
	int window_size = MIN_RELIABLE_WINDOW_SIZE;

	u16 next_incoming_seqnum = SEQNUM_INITIAL;

	u16 next_outgoing_seqnum = SEQNUM_INITIAL;
	u16 next_outgoing_split_seqnum = SEQNUM_INITIAL;

	unsigned int current_packet_loss = 0;
	unsigned int current_packet_too_late = 0;
	unsigned int current_packet_successful = 0;
	float packet_loss_counter = 0.0f;

	unsigned int current_bytes_transfered = 0;
	unsigned int current_bytes_received = 0;
	unsigned int current_bytes_lost = 0;
	float max_kbps = 0.0f;
	float cur_kbps = 0.0f;
	float avg_kbps = 0.0f;
	float max_incoming_kbps = 0.0f;
	float cur_incoming_kbps = 0.0f;
	float avg_incoming_kbps = 0.0f;
	float max_kbps_lost = 0.0f;
	float cur_kbps_lost = 0.0f;
	float avg_kbps_lost = 0.0f;
	float bpm_counter = 0.0f;

	unsigned int rate_samples = 0;
};

class Peer;

class PeerHelper
{
public:
	PeerHelper() = default;
	PeerHelper(Peer* peer);
	~PeerHelper();

	PeerHelper&   operator=(Peer* peer);
	Peer*         operator->() const;
	bool          operator!();
	Peer*         operator&() const;
	bool          operator!=(void* ptr);

private:
	Peer *m_peer = nullptr;
};

class Connection;

typedef enum {
	CUR_DL_RATE,
	AVG_DL_RATE,
	CUR_INC_RATE,
	AVG_INC_RATE,
	CUR_LOSS_RATE,
	AVG_LOSS_RATE,
} rate_stat_type;

class Peer {
	public:
		friend class PeerHelper;

		Peer(Address address_,u16 id_,Connection* connection) :
			id(id_),
			m_connection(connection),
			address(address_),
			m_last_timeout_check(porting::getTimeMs())
		{
		};

		virtual ~Peer() {
			MutexAutoLock usage_lock(m_exclusive_access_mutex);
			FATAL_ERROR_IF(m_usage != 0, "Reference counting failure");
		};

		// Unique id of the peer
		u16 id;

		void Drop();

		virtual void PutReliableSendCommand(ConnectionCommand &c,
						unsigned int max_packet_size) {};

		virtual bool getAddress(MTProtocols type, Address& toset) = 0;

		bool isPendingDeletion()
		{ MutexAutoLock lock(m_exclusive_access_mutex); return m_pending_deletion; };

		void ResetTimeout()
			{MutexAutoLock lock(m_exclusive_access_mutex); m_timeout_counter = 0.0; };

		bool isTimedOut(float timeout);

		unsigned int m_increment_packets_remaining = 0;

		virtual u16 getNextSplitSequenceNumber(u8 channel) { return 0; };
		virtual void setNextSplitSequenceNumber(u8 channel, u16 seqnum) {};
		virtual SharedBuffer<u8> addSplitPacket(u8 channel, const BufferedPacket &toadd,
				bool reliable)
		{
			errorstream << "Peer::addSplitPacket called,"
					<< " this is supposed to be never called!" << std::endl;
			return SharedBuffer<u8>(0);
		};

		virtual bool Ping(float dtime, SharedBuffer<u8>& data) { return false; };

		virtual float getStat(rtt_stat_type type) const {
			switch (type) {
				case MIN_RTT:
					return m_rtt.min_rtt;
				case MAX_RTT:
					return m_rtt.max_rtt;
				case AVG_RTT:
					return m_rtt.avg_rtt;
				case MIN_JITTER:
					return m_rtt.jitter_min;
				case MAX_JITTER:
					return m_rtt.jitter_max;
				case AVG_JITTER:
					return m_rtt.jitter_avg;
			}
			return -1;
		}
	protected:
		virtual void reportRTT(float rtt) {};

		void RTTStatistics(float rtt,
							const std::string &profiler_id = "",
							unsigned int num_samples = 1000);

		bool IncUseCount();
		void DecUseCount();

		std::mutex m_exclusive_access_mutex;

		bool m_pending_deletion = false;

		Connection* m_connection;

		// Address of the peer
		Address address;

		// Ping timer
		float m_ping_timer = 0.0f;
	private:

		struct rttstats {
			float jitter_min = FLT_MAX;
			float jitter_max = 0.0f;
			float jitter_avg = -1.0f;
			float min_rtt = FLT_MAX;
			float max_rtt = 0.0f;
			float avg_rtt = -1.0f;

			rttstats() = default;
		};

		rttstats m_rtt;
		float m_last_rtt = -1.0f;

		// current usage count
		unsigned int m_usage = 0;

		// Seconds from last receive
		float m_timeout_counter = 0.0f;

		u64 m_last_timeout_check;
};

class UDPPeer : public Peer
{
public:

	friend class PeerHelper;
	friend class ConnectionReceiveThread;
	friend class ConnectionSendThread;
	friend class Connection;

	UDPPeer(u16 a_id, Address a_address, Connection* connection);
	virtual ~UDPPeer() = default;

	void PutReliableSendCommand(ConnectionCommand &c,
							unsigned int max_packet_size);

	bool getAddress(MTProtocols type, Address& toset);

	u16 getNextSplitSequenceNumber(u8 channel);
	void setNextSplitSequenceNumber(u8 channel, u16 seqnum);

	SharedBuffer<u8> addSplitPacket(u8 channel, const BufferedPacket &toadd,
		bool reliable);

protected:
	/*
		Calculates avg_rtt and resend_timeout.
		rtt=-1 only recalculates resend_timeout
	*/
	void reportRTT(float rtt);

	void RunCommandQueues(
					unsigned int max_packet_size,
					unsigned int maxcommands,
					unsigned int maxtransfer);

	float getResendTimeout()
		{ MutexAutoLock lock(m_exclusive_access_mutex); return resend_timeout; }

	void setResendTimeout(float timeout)
		{ MutexAutoLock lock(m_exclusive_access_mutex); resend_timeout = timeout; }
	bool Ping(float dtime,SharedBuffer<u8>& data);

	Channel channels[CHANNEL_COUNT];
	bool m_pending_disconnect = false;
private:
	// This is changed dynamically
	float resend_timeout = 0.5;

	bool processReliableSendCommand(
					ConnectionCommand &c,
					unsigned int max_packet_size);
};

/*
	Connection
*/

enum ConnectionEventType{
	CONNEVENT_NONE,
	CONNEVENT_DATA_RECEIVED,
	CONNEVENT_PEER_ADDED,
	CONNEVENT_PEER_REMOVED,
	CONNEVENT_BIND_FAILED,
};

struct ConnectionEvent
{
	enum ConnectionEventType type = CONNEVENT_NONE;
	session_t peer_id = 0;
	Buffer<u8> data;
	bool timeout = false;
	Address address;

	ConnectionEvent() = default;

	std::string describe()
	{
		switch(type) {
		case CONNEVENT_NONE:
			return "CONNEVENT_NONE";
		case CONNEVENT_DATA_RECEIVED:
			return "CONNEVENT_DATA_RECEIVED";
		case CONNEVENT_PEER_ADDED:
			return "CONNEVENT_PEER_ADDED";
		case CONNEVENT_PEER_REMOVED:
			return "CONNEVENT_PEER_REMOVED";
		case CONNEVENT_BIND_FAILED:
			return "CONNEVENT_BIND_FAILED";
		}
		return "Invalid ConnectionEvent";
	}

	void dataReceived(session_t peer_id_, const SharedBuffer<u8> &data_)
	{
		type = CONNEVENT_DATA_RECEIVED;
		peer_id = peer_id_;
		data = data_;
	}
	void peerAdded(session_t peer_id_, Address address_)
	{
		type = CONNEVENT_PEER_ADDED;
		peer_id = peer_id_;
		address = address_;
	}
	void peerRemoved(session_t peer_id_, bool timeout_, Address address_)
	{
		type = CONNEVENT_PEER_REMOVED;
		peer_id = peer_id_;
		timeout = timeout_;
		address = address_;
	}
	void bindFailed()
	{
		type = CONNEVENT_BIND_FAILED;
	}
};

class PeerHandler;

class Connection
{
public:
	friend class ConnectionSendThread;
	friend class ConnectionReceiveThread;

	Connection(u32 protocol_id, u32 max_packet_size, float timeout, bool ipv6,
			PeerHandler *peerhandler);
	~Connection();

	/* Interface */
	ConnectionEvent waitEvent(u32 timeout_ms);
	void putCommand(ConnectionCommand &c);

	void SetTimeoutMs(u32 timeout) { m_bc_receive_timeout = timeout; }
	void Serve(Address bind_addr);
	void Connect(Address address);
	bool Connected();
	void Disconnect();
	void Receive(NetworkPacket* pkt);
	bool TryReceive(NetworkPacket *pkt);
	void Send(session_t peer_id, u8 channelnum, NetworkPacket *pkt, bool reliable);
	session_t GetPeerID() const { return m_peer_id; }
	Address GetPeerAddress(session_t peer_id);
	float getPeerStat(session_t peer_id, rtt_stat_type type);
	float getLocalStat(rate_stat_type type);
	const u32 GetProtocolID() const { return m_protocol_id; };
	const std::string getDesc();
	void DisconnectPeer(session_t peer_id);

protected:
	PeerHelper getPeerNoEx(session_t peer_id);
	u16   lookupPeer(Address& sender);

	u16 createPeer(Address& sender, MTProtocols protocol, int fd);
	UDPPeer*  createServerPeer(Address& sender);
	bool deletePeer(session_t peer_id, bool timeout);

	void SetPeerID(session_t id) { m_peer_id = id; }

	void sendAck(session_t peer_id, u8 channelnum, u16 seqnum);

	void PrintInfo(std::ostream &out);

	std::vector<session_t> getPeerIDs()
	{
		MutexAutoLock peerlock(m_peers_mutex);
		return m_peer_ids;
	}

	UDPSocket m_udpSocket;
	MutexedQueue<ConnectionCommand> m_command_queue;

	bool Receive(NetworkPacket *pkt, u32 timeout);

	void putEvent(ConnectionEvent &e);

	void TriggerSend();
	
	bool ConnectedToServer() 
	{
		return getPeerNoEx(PEER_ID_SERVER) != nullptr;
	}
private:
	MutexedQueue<ConnectionEvent> m_event_queue;

	session_t m_peer_id = 0;
	u32 m_protocol_id;

	std::map<session_t, Peer *> m_peers;
	std::vector<session_t> m_peer_ids;
	std::mutex m_peers_mutex;

	std::unique_ptr<ConnectionSendThread> m_sendThread;
	std::unique_ptr<ConnectionReceiveThread> m_receiveThread;

	std::mutex m_info_mutex;

	// Backwards compatibility
	PeerHandler *m_bc_peerhandler;
	u32 m_bc_receive_timeout = 0;

	bool m_shutting_down = false;

	session_t m_next_remote_peer_id = 2;
};

} // namespace