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#include "stdafx.h"

     2

#include "ttd.h"

     4

#include "command.h"

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#include "player.h"

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     7

#if defined(WIN32)

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#	include <windows.h>

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#	include <winsock.h>

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# pragma comment (lib, "ws2_32.lib")

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# define ENABLE_NETWORK

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# define GET_LAST_ERROR() WSAGetLastError()

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# define EWOULDBLOCK WSAEWOULDBLOCK

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#endif

    16

    17

#if defined(UNIX)

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// Make compatible with WIN32 names

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#	define SOCKET int

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#	define INVALID_SOCKET -1

    21

// we need different defines for MorphOS and AmigaOS

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#if !defined(__MORPHOS__) && !defined(__AMIGA__)

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#	define ioctlsocket ioctl

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# define closesocket close

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# define GET_LAST_ERROR() errno

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#endif

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// Need this for FIONREAD on solaris

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#	define BSD_COMP

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#	include <unistd.h>

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#	include <sys/ioctl.h>

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// Socket stuff

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#	include <sys/socket.h>

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#	include <netinet/in.h>

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#	include <arpa/inet.h>

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# 	include <errno.h>

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# 	include <sys/time.h>

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// NetDB

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#   include <netdb.h>

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    41

# ifndef TCP_NODELAY

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#  define TCP_NODELAY 0x0001

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# endif

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#endif

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    47

    48

#if defined(__MORPHOS__) || defined(__AMIGA__)

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#	include <exec/types.h>

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#	include <proto/exec.h> 		// required for Open/CloseLibrary()

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#	if defined(__MORPHOS__)

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#		include <sys/filio.h> 	// FION#? defines

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#	else // __AMIGA__

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#		include	<proto/socket.h>

    55

#	endif

    56

    57

// make source compatible with bsdsocket.library functions

    58

# define closesocket(s)     						CloseSocket(s)

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# define GET_LAST_ERROR() 							Errno()

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#	define ioctlsocket(s,request,status)  IoctlSocket((LONG)s,(ULONG)request,(char*)status)

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    62

struct Library *SocketBase = NULL;

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#endif /* __MORPHOS__ || __AMIGA__ */

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    65

    66

#define SEND_MTU 1460

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    68

#if defined(ENABLE_NETWORK)

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    70

// sent from client -> server whenever the client wants to exec a command.

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// send from server -> client when another player execs a command.

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typedef struct CommandPacket {

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	byte packet_length;

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	byte packet_type;

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	uint16 cmd;

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	uint32 p1,p2;

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	TileIndex tile;

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	byte player;// player id, this is checked by the server.

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	byte when;  // offset from the current max_frame value minus 1. this is set by the server.

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	uint32 dp[8];

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} CommandPacket;

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    83

assert_compile(sizeof(CommandPacket) == 16 + 32);

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    85

#define COMMAND_PACKET_BASE_SIZE (sizeof(CommandPacket) - 8 * sizeof(uint32))

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    87

// sent from server -> client periodically to tell the client about the current tick in the server

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// and how far the client may progress.

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typedef struct SyncPacket {

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	byte packet_length;

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	byte packet_type;

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	byte frames; // how many more frames may the client execute? this is relative to the old value of max.

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	byte server; // where is the server currently executing? this is negatively relative to the old value of max.

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	uint32 random_seed_1; // current random state at server. used to detect out of sync.

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	uint32 random_seed_2;

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} SyncPacket;

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    98

assert_compile(sizeof(SyncPacket) == 12);

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   100

// sent from server -> client as an acknowledgement that the server received the command.

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// the command will be executed at the current value of "max".

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typedef struct AckPacket {

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	byte packet_length;

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	byte packet_type;

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} AckPacket;

   106

   107

typedef struct FilePacketHdr {

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	byte packet_length;

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	byte packet_type;

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	byte unused[2];

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} FilePacketHdr;

   112

   113

assert_compile(sizeof(FilePacketHdr) == 4);

   114

   115

// sent from server to client when the client has joined.

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typedef struct WelcomePacket {

   117

	byte packet_length;

   118

	byte packet_type;

   119

	byte unused[2];

   120

} WelcomePacket;

   121

   122

typedef struct Packet Packet;

   123

struct Packet {

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	Packet *next; // this one has to be the first element.

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	uint siz;

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	byte buf[SEND_MTU]; // packet payload

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};

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   129

typedef struct ClientState {

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	int socket;

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	bool inactive; // disable sending of commands/syncs to client

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	bool writable;

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	uint xmitpos;

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   135

	uint eaten;

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	Packet *head, **last;

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   138

	uint buflen;											// receive buffer len

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	byte buf[256];										// receive buffer

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} ClientState;

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   142

   143

static uint _not_packet;

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   145

typedef struct QueuedCommand QueuedCommand;

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struct QueuedCommand {

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	QueuedCommand *next;

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	CommandPacket cp;

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	CommandCallback *callback;

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	uint32 cmd;

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	int32 frame;

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};

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   154

typedef struct CommandQueue CommandQueue;

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struct CommandQueue {

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	QueuedCommand *head, **last;

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};

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   159

#define MAX_CLIENTS (MAX_PLAYERS + 1)

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   161

// packets waiting to be executed, for each of the players.

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// this list is sorted in frame order, so the item on the front will be executed first.

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static CommandQueue _command_queue;

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   165

// in the client, this is the list of commands that have not yet been acked.

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// when it is acked, it will be moved to the appropriate position at the end of the player queue.

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static CommandQueue _ack_queue;

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   169

static ClientState _clients[MAX_CLIENTS];

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static int _num_clients;

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   172

// keep a history of the 16 most recent seeds to be able to capture out of sync errors.

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static uint32 _my_seed_list[16][2];

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   175

typedef struct FutureSeeds {

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	int32 frame;

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	uint32 seed[2];

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} FutureSeeds;

   179

   180

// remember some future seeds that the server sent to us.

   181

static FutureSeeds _future_seed[8];

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static int _num_future_seed;

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   185

   188

   189

typedef struct UDPPacket {

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	byte command_code;

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	byte data_len;

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	byte command_check;

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	byte data[255];

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} UDPPacket;

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   196

enum {

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	NET_UDPCMD_SERVERSEARCH = 1,

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	NET_UDPCMD_SERVERACTIVE,

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};

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   207

// this is set to point to the savegame

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static byte *_transmit_file;

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static size_t _transmit_file_size;

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   211

static FILE *_recv_file;

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   252

//////////////////////////////////////////////////////////////////////

   253

   258

static QueuedCommand *AllocQueuedCommand(CommandQueue *nq)

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{

   260

	QueuedCommand *qp = (QueuedCommand*)calloc(sizeof(QueuedCommand), 1);

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	assert(qp);

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	*nq->last = qp;

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	nq->last = &qp->next;

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	return qp;

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}

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   267

// go through the player queues for each player and see if there are any pending commands

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// that should be executed this frame. if there are, execute them.

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void NetworkProcessCommands()

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{

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	CommandQueue *nq;

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	QueuedCommand *qp;

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   274

	// queue mode ?

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	if (_networking_queuing)

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		return;

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   278

	nq = &_command_queue;

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	while ( (qp=nq->head) && (!_networking_sync || qp->frame <= _frame_counter)) {

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		// unlink it.

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		if (!(nq->head = qp->next)) nq->last = &nq->head;

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   283

		if (qp->frame < _frame_counter && _networking_sync) {

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			error("!qp->cp.frame < _frame_counter, %d < %d\n", qp->frame, _frame_counter);

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		}

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   287

		// run the command

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		_current_player = qp->cp.player;

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		memcpy(_decode_parameters, qp->cp.dp, (qp->cp.packet_length - COMMAND_PACKET_BASE_SIZE));

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		DoCommandP(qp->cp.tile, qp->cp.p1, qp->cp.p2, qp->callback, qp->cmd | CMD_DONT_NETWORK);

   291

		free(qp);

   292

	}

   293

   294

	if (!_networking_server) {

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		// remember the random seed so we can check if we're out of sync.

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		_my_seed_list[_frame_counter & 15][0] = _sync_seed_1;

   297

		_my_seed_list[_frame_counter & 15][1] = _sync_seed_2;

   298

   299

		while (_num_future_seed) {

   300

			assert(_future_seed[0].frame >= _frame_counter);

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			if (_future_seed[0].frame != _frame_counter) break;

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			if (_future_seed[0].seed[0] != _sync_seed_1 ||_future_seed[0].seed[1] != _sync_seed_2)

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				error("!network sync error");

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			memcpy_overlapping(_future_seed, _future_seed + 1, --_num_future_seed * sizeof(FutureSeeds));

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		}

   306

	}

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}

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   309

// send a packet to a client

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static void SendBytes(ClientState *cs, void *bytes, uint len)

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{

   312

	byte *b = (byte*)bytes;

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	uint n;

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	Packet *p;

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	assert(len != 0);

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   318

	// see if there's space in the last packet?

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	if (!cs->head || (p = (Packet*)cs->last, p->siz == sizeof(p->buf)))

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		p = NULL;

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	do {

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		if (!p) {

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			// need to allocate a new packet buffer.

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			p = (Packet*)malloc(sizeof(Packet));

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			// insert at the end of the linked list.

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			*cs->last = p;

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			cs->last = &p->next;

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			p->next = NULL;

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			p->siz = 0;

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		}

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		// copy bytes to packet.

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		n = minu(sizeof(p->buf) - p->siz, len);

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		memcpy(p->buf + p->siz, b, n);

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		p->siz += n;

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		b += n;

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		p = NULL;

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	} while (len -= n);

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}

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   343

// client:

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//   add it to the client's ack queue, and send the command to the server

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// server:

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//   add it to the server's player queue, and send it to all clients.

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void NetworkSendCommand(TileIndex tile, uint32 p1, uint32 p2, uint32 cmd, CommandCallback *callback)

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{

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	int nump;

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	QueuedCommand *qp;

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	ClientState *cs;

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	qp = AllocQueuedCommand(_networking_server ? &_command_queue : &_ack_queue);

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	qp->cp.packet_type = 0;

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	qp->cp.tile = tile;

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	qp->cp.p1 = p1;

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	qp->cp.p2 = p2;

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	qp->cp.cmd = (uint16)cmd;

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	qp->cp.player = _local_player;

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	qp->cp.when = 0;

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	qp->cmd = cmd;

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	qp->callback = callback;

   363

   364

	// so the server knows when to execute it.

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	qp->frame = _frame_counter_max;

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   367

	// calculate the amount of extra bytes.

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	nump = 8;

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	while ( nump != 0 && ((uint32*)_decode_parameters)[nump-1] == 0) nump--;

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	qp->cp.packet_length = COMMAND_PACKET_BASE_SIZE + nump * sizeof(uint32);

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	if (nump != 0) memcpy(qp->cp.dp, _decode_parameters, nump * sizeof(uint32));

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#if defined(TTD_BIG_ENDIAN)

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	// need to convert the command to little endian before sending it.

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	{

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		CommandPacket cp;

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		cp = qp->cp;

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		cp.cmd = TO_LE16(cp.cmd);

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		cp.tile = TO_LE16(cp.tile);

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		cp.p1 = TO_LE32(cp.p1);

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		cp.p2 = TO_LE32(cp.p2);

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		for(cs=_clients; cs->socket != INVALID_SOCKET; cs++) if (!cs->inactive) SendBytes(cs, &cp, cp.packet_length);

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	}

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#else

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	// send it to the peers

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	for(cs=_clients; cs->socket != INVALID_SOCKET; cs++) if (!cs->inactive) SendBytes(cs, &qp->cp, qp->cp.packet_length);

   387

   388

#endif

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}

   390

   391

// client:

   392

//   server sends a command from another player that we should execute.

   393

//   put it in the command queue.

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//

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// server:

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//   client sends a command that it wants to execute.

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//   fill the when field so the client knows when to execute it.

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//   put it in the appropriate player queue.

   399

//   send it to all other clients.

   400

//   send an ack packet to the actual client.

   401

   402

static void HandleCommandPacket(ClientState *cs, CommandPacket *np)

   403

{

   404

	QueuedCommand *qp;

   405

	ClientState *c;

   406

	AckPacket ap;

   407

   408

	printf("net: cmd size %d\n", np->packet_length);

   409

   410

	assert(np->packet_length >= COMMAND_PACKET_BASE_SIZE);

   411

   412

	// put it into the command queue

   413

	qp = AllocQueuedCommand(&_command_queue);

   414

	qp->cp = *np;

   415

   416

	qp->frame = _frame_counter_max;

   417

   418

	qp->callback = NULL;

   419

   420

	// extra params

   421

	memcpy(&qp->cp.dp, np->dp, np->packet_length - COMMAND_PACKET_BASE_SIZE);

   422

   423

	ap.packet_type = 2;

   424

	ap.packet_length = 2;

   425

   426

	// send it to the peers

   427

	if (_networking_server) {

   428

		for(c=_clients; c->socket != INVALID_SOCKET; c++) {

   429

			if (c == cs) {

   430

				SendBytes(c, &ap, 2);

   431

			} else {

   432

				if (!cs->inactive) SendBytes(c, &qp->cp, qp->cp.packet_length);

   433

			}

   434

		}

   435

	}

   436

   437

// convert from little endian to big endian?

   438

#if defined(TTD_BIG_ENDIAN)

   439

	qp->cp.cmd = TO_LE16(qp->cp.cmd);

   440

	qp->cp.tile = TO_LE16(qp->cp.tile);

   441

	qp->cp.p1 = TO_LE32(qp->cp.p1);

   442

	qp->cp.p2 = TO_LE32(qp->cp.p2);

   443

#endif

   444

   445

	qp->cmd = qp->cp.cmd;

   446

}

   447

   448

// sent from server -> client periodically to tell the client about the current tick in the server

   449

// and how far the client may progress.

   450

static void HandleSyncPacket(SyncPacket *sp)

   451

{

   452

	uint32 s1,s2;

   453

   454

	_frame_counter_srv = _frame_counter_max - sp->server;

   455

	_frame_counter_max += sp->frames;

   456

   457

	printf("net: sync max=%d  cur=%d  server=%d\n", _frame_counter_max, _frame_counter, _frame_counter_srv);

   458

   459

	// queueing only?

   460

	if (_networking_queuing || _frame_counter == 0)

   461

		return;

   462

   463

	s1 = TO_LE32(sp->random_seed_1);

   464

	s2 = TO_LE32(sp->random_seed_2);

   465

   466

	if (_frame_counter_srv <= _frame_counter) {

   467

		// we are ahead of the server check if the seed is in our list.

   468

		if (_frame_counter_srv + 16 > _frame_counter) {

   469

			// the random seed exists in our array check it.

   470

			if (s1 != _my_seed_list[_frame_counter_srv & 0xF][0] || s2 != _my_seed_list[_frame_counter_srv & 0xF][1])

   471

				error("!network is desynched\n");

   472

		}

   473

	} else {

   474

		// the server's frame has not been executed yet. store the server's seed in a list.

   475

		if (_num_future_seed < lengthof(_future_seed)) {

   476

			_future_seed[_num_future_seed].frame = _frame_counter_srv;

   477

			_future_seed[_num_future_seed].seed[0] = s1;

   478

			_future_seed[_num_future_seed].seed[1] = s2;

   479

			_num_future_seed++;

   480

		}

   481

	}

   482

}

   483

   484

// sent from server -> client as an acknowledgement that the server received the command.

   485

// the command will be executed at the current value of "max".

   486

static void HandleAckPacket()

   487

{

   488

	QueuedCommand *q;

   489

	// move a packet from the ack queue to the end of this player's queue.

   490

	q = _ack_queue.head;

   491

	assert(q);

   492

	if (!(_ack_queue.head = q->next)) _ack_queue.last = &_ack_queue.head;

   493

	q->next = NULL;

   494

	q->frame = _frame_counter_max;

   495

   496

	*_command_queue.last = q;

   497

	_command_queue.last = &q->next;

   498

   499

	printf("net: ack\n");

   500

}

   501

   502

static void HandleFilePacket(FilePacketHdr *fp)

   503

{

   504

	int n = fp->packet_length - sizeof(FilePacketHdr);

   505

	if (n == 0) {

   506

		assert(_networking_queuing);

   507

		assert(!_networking_sync);

   508

		// eof

   509

		if (_recv_file) { fclose(_recv_file); _recv_file = NULL; }

   510

   511

		// attempt loading the game.

   512

		_game_mode = GM_NORMAL;

   513

		if (SaveOrLoad("networkc.tmp", SL_LOAD) != SL_OK) error("network load failed");

   514

   515

		// sync to server.

   516

		_networking_queuing = false;

   519

		_networking_sync = true;

   520

		_frame_counter = 0; // start executing at frame 0.

   521

		_sync_seed_1 = _sync_seed_2 = 0;

   522

		_num_future_seed = 0;

   524