snes9x/netplay.cpp

/*****************************************************************************\
     Snes9x - Portable Super Nintendo Entertainment System (TM) emulator.
                This file is licensed under the Snes9x License.
   For further information, consult the LICENSE file in the root directory.
\*****************************************************************************/

#ifdef NETPLAY_SUPPORT

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <memory.h>
#include <sys/types.h>

#include "snes9x.h"

#ifdef __WIN32__
	#include <winsock.h>
	#include <process.h>
	#include "win32/wsnes9x.h"

	#define ioctl ioctlsocket
	#define close(h) if(h){closesocket(h);}
	#define read(a,b,c) recv(a, b, c, 0)
	#define write(a,b,c) send(a, b, c, 0)
#else
	#include <unistd.h>
	#include <sys/time.h>
	#include <sys/types.h>
	#include <sys/stat.h>

	#include <netdb.h>
	#include <sys/ioctl.h>
	#include <sys/socket.h>
	#include <sys/param.h>
	#include <netinet/in.h>
	#include <arpa/inet.h>

	#ifdef __SVR4
		#include <sys/stropts.h>
	#endif
#endif

#ifdef USE_THREADS
#include <pthread.h>
#include <sched.h>
#include <semaphore.h>
#endif

#include "memmap.h"
#include "netplay.h"
#include "snapshot.h"
#include "display.h"

void S9xNPClientLoop (void *);
bool8 S9xNPLoadROM (uint32 len);
bool8 S9xNPLoadROMDialog (const char *);
bool8 S9xNPGetROMImage (uint32 len);
void S9xNPGetSRAMData (uint32 len);
void S9xNPGetFreezeFile (uint32 len);

unsigned long START = 0;

bool8 S9xNPConnect ();

bool8 S9xNPConnectToServer (const char *hostname, int port,
                            const char *rom_name)
{
    if (!S9xNPInitialise ())
        return (FALSE);

    S9xNPDisconnect ();

    NetPlay.MySequenceNum = 0;
    NetPlay.ServerSequenceNum = 0;
    NetPlay.Connected = FALSE;
    NetPlay.Abort = FALSE;
    NetPlay.Player = 0;
    NetPlay.Paused = FALSE;
    NetPlay.PercentageComplete = 0;
    NetPlay.Socket = 0;
    if (NetPlay.ServerHostName)
        free ((char *) NetPlay.ServerHostName);
    NetPlay.ServerHostName = strdup (hostname);
    if (NetPlay.ROMName)
        free ((char *) NetPlay.ROMName);
    NetPlay.ROMName = strdup (rom_name);
    NetPlay.Port = port;
    NetPlay.PendingWait4Sync = FALSE;

#ifdef __WIN32__
    if (GUI.ClientSemaphore == NULL)
        GUI.ClientSemaphore = CreateSemaphore (NULL, 0, NP_JOYPAD_HIST_SIZE, NULL);

    if (NetPlay.ReplyEvent == NULL)
        NetPlay.ReplyEvent = CreateEvent (NULL, FALSE, FALSE, NULL);

    _beginthread (S9xNPClientLoop, 0, NULL);

    return (TRUE);
#endif

    return S9xNPConnect();
}

bool8 S9xNPConnect ()
{
    struct sockaddr_in address;
    struct hostent *hostinfo;
    unsigned int addr;

    address.sin_family = AF_INET;
    address.sin_port = htons (NetPlay.Port);
#ifdef NP_DEBUG
    printf ("CLIENT: Looking up server's hostname (%s) @%ld\n", NetPlay.ServerHostName, S9xGetMilliTime () - START);
#endif
    S9xNPSetAction ("Looking up server's hostname...");
    if ((int) (addr = inet_addr (NetPlay.ServerHostName)) == -1)
    {
	if ((hostinfo = gethostbyname (NetPlay.ServerHostName)))
	{
	    memcpy ((char *)&address.sin_addr, hostinfo->h_addr,
		    hostinfo->h_length);
	}
	else
	{
            S9xNPSetError ("\
Unable to look up server's IP address from hostname.\n\n\
Unknown hostname or may be your nameserver isn't set\n\
up correctly?");
	    return (FALSE);
	}
    }
    else
    {
	memcpy ((char *)&address.sin_addr, &addr, sizeof (addr));
    }

#ifdef NP_DEBUG
    printf ("CLIENT: Creating socket @%ld\n", S9xGetMilliTime () - START);
#endif
    S9xNPSetAction ("Creating network socket...");
    if ((NetPlay.Socket = socket (AF_INET, SOCK_STREAM, 0)) < 0)
    {
        S9xNPSetError ("Creating network socket failed.");
	return (FALSE);
    }

#ifdef NP_DEBUG
    printf ("CLIENT: Trying to connect to server @%ld...\n", S9xGetMilliTime () - START);
#endif
    S9xNPSetAction ("Trying to connect to Snes9x server...");

    if (connect (NetPlay.Socket, (struct sockaddr *) &address, sizeof (address)) < 0)
    {
        char buf [100];
#ifdef __WIN32__
        if (WSAGetLastError () == WSAECONNREFUSED)
#else
	if (errno == ECONNREFUSED)
#endif
        {
            S9xNPSetError ("\
Connection to remote server socket refused:\n\n\
Is there actually a Snes9x NetPlay server running\n\
on the remote machine on this port?");
        }
        else
        {
            sprintf (buf, "Connection to server failed with error number %d",
#ifdef __WIN32__
                     WSAGetLastError ()
#else
		     errno
#endif
		     );
            S9xNPSetError(buf);
            S9xNPDisconnect ();
        }
	return (FALSE);
    }
    NetPlay.Connected = TRUE;

#ifdef NP_DEBUG
    printf ("CLIENT: Sending 'HELLO' message @%ld...\n", S9xGetMilliTime () - START);
#endif
    S9xNPSetAction ("Sending 'HELLO' message...");
    /* Send the server a HELLO packet*/
    int len = 7 + 4 + strlen (NetPlay.ROMName) + 1;
    uint8 *tmp = new uint8 [len];
    uint8 *ptr = tmp;

    *ptr++ = NP_CLNT_MAGIC;
    *ptr++ = NetPlay.MySequenceNum++;
    *ptr++ = NP_CLNT_HELLO;
    WRITE_LONG (ptr, len);
    ptr += 4;
#ifdef __WIN32__
    uint32 ft = Settings.FrameTime;

    WRITE_LONG (ptr, ft);
#else
    WRITE_LONG (ptr, Settings.FrameTime);
#endif
    ptr += 4;
    strcpy ((char *) ptr, NetPlay.ROMName);

    if (!S9xNPSendData (NetPlay.Socket, tmp, len))
    {
        S9xNPSetError ("Sending 'HELLO' message failed.");
	S9xNPDisconnect ();
	delete[] tmp;
	return (FALSE);
    }
    delete[] tmp;

#ifdef NP_DEBUG
    printf ("CLIENT: Waiting for 'WELCOME' reply from server @%ld...\n", S9xGetMilliTime () - START);
#endif
    S9xNPSetAction ("Waiting for 'HELLO' reply from server...");

    uint8 header [7];

    if (!S9xNPGetData (NetPlay.Socket, header, 7) ||
        header [0] != NP_SERV_MAGIC || header [1] != 0 ||
        (header [2] & 0x1f) != NP_SERV_HELLO)
    {
        S9xNPSetError ("Error in 'HELLO' reply packet received from server.");
	S9xNPDisconnect ();
	return (FALSE);
    }
#ifdef NP_DEBUG
    printf ("CLIENT: Got 'WELCOME' reply @%ld\n", S9xGetMilliTime () - START);
#endif
    len = READ_LONG (&header [3]);
    if (len > 256)
    {
        S9xNPSetError ("Error in 'HELLO' reply packet received from server.");
	S9xNPDisconnect ();
	return (FALSE);
    }
    uint8 *data = new uint8 [len];
    if (!S9xNPGetData (NetPlay.Socket, data, len - 7))
    {
        S9xNPSetError ("Error in 'HELLO' reply packet received from server.");
        delete[] data;
	S9xNPDisconnect ();
	return (FALSE);
    }

    if (data [0] != NP_VERSION)
    {
        S9xNPSetError ("\
The Snes9x NetPlay server implements a different\n\
version of the protocol. Disconnecting.");
        delete[] data;
	S9xNPDisconnect ();
        return (FALSE);
    }

    NetPlay.FrameCount = READ_LONG (&data [2]);

    if (!(header [2] & 0x80) &&
        strcmp ((char *) data + 4 + 2, NetPlay.ROMName) != 0)
    {
        if (!S9xNPLoadROMDialog ((char *) data + 4 + 2))
        {
            delete[] data;
            S9xNPDisconnect ();
            return (FALSE);
        }
    }
    NetPlay.Player = data [1];
    delete[] data;

    NetPlay.PendingWait4Sync = TRUE;
    Settings.NetPlay = TRUE;
    S9xNPResetJoypadReadPos ();
    NetPlay.ServerSequenceNum = 1;

#ifdef NP_DEBUG
    printf ("CLIENT: Sending 'READY' to server @%ld...\n", S9xGetMilliTime () - START);
#endif
    S9xNPSetAction ("Sending 'READY' to the server...");

    return (S9xNPSendReady ((header [2] & 0x80) ?
                            NP_CLNT_WAITING_FOR_ROM_IMAGE :
                            NP_CLNT_READY));
}

bool8 S9xNPSendReady (uint8 op)
{
    uint8 ready [7];
    uint8 *ptr = ready;
    *ptr++ = NP_CLNT_MAGIC;
    *ptr++ = NetPlay.MySequenceNum++;
    *ptr++ = op;
    WRITE_LONG (ptr, 7);
    ptr += 4;

    if (!S9xNPSendData (NetPlay.Socket, ready, 7))
    {
	S9xNPDisconnect ();
        S9xNPSetError ("Sending 'READY' message failed.");
	return (FALSE);
    }

    return (TRUE);
}

bool8 S9xNPSendPause (bool8 paused)
{
#ifdef NP_DEBUG
    printf ("CLIENT: Pause - %s @%ld\n", paused ? "YES" : "NO", S9xGetMilliTime () - START);
#endif
    uint8 pause [7];
    uint8 *ptr = pause;
    *ptr++ = NP_CLNT_MAGIC;
    *ptr++ = NetPlay.MySequenceNum++;
    *ptr++ = NP_CLNT_PAUSE | (paused ? 0x80 : 0);
    WRITE_LONG (ptr, 7);
    ptr += 4;

    if (!S9xNPSendData (NetPlay.Socket, pause, 7))
    {
        S9xNPSetError ("Sending 'PAUSE' message failed.");
	S9xNPDisconnect ();
	return (FALSE);
    }

    return (TRUE);
}

#ifdef __WIN32__
void S9xNPClientLoop (void *)
{
    NetPlay.Waiting4EmulationThread = FALSE;

    if (S9xNPConnect ())
    {
        S9xClearPause (PAUSE_NETPLAY_CONNECT);
        while (NetPlay.Connected)
        {
            if (S9xNPWaitForHeartBeat ())
            {
                LONG prev;
                if (!ReleaseSemaphore (GUI.ClientSemaphore, 1, &prev))
                {
#ifdef NP_DEBUG
                    printf ("CLIENT: ReleaseSemaphore failed - already hit max count (%d) %ld\n", NP_JOYPAD_HIST_SIZE, S9xGetMilliTime () - START);
#endif
                    S9xNPSetWarning ("NetPlay: Client may be out of sync with server.");
                }
                else
                {
                    if (!NetPlay.Waiting4EmulationThread &&
                        prev == (int) NetPlay.MaxBehindFrameCount)
                    {
                        NetPlay.Waiting4EmulationThread = TRUE;
                        S9xNPSendPause (TRUE);
                    }
                }
            }
            else
                S9xNPDisconnect ();
        }
    }
    else
    {
        S9xClearPause (PAUSE_NETPLAY_CONNECT);
    }
#ifdef NP_DEBUG
    printf ("CLIENT: Client thread exiting @%ld\n", S9xGetMilliTime () - START);
#endif
}
#endif

bool8 S9xNPCheckForHeartBeat (uint32 time_msec)
{
    fd_set read_fds;
    struct timeval timeout;
    int res;
    int i;

    int max_fd = NetPlay.Socket;

    FD_ZERO (&read_fds);
    FD_SET (NetPlay.Socket, &read_fds);

    timeout.tv_sec = 0;
    timeout.tv_usec = time_msec * 1000;
    res = select (max_fd + 1, &read_fds, NULL, NULL, &timeout);

    i = (res > 0 && FD_ISSET(NetPlay.Socket, &read_fds));

#if defined(NP_DEBUG) && NP_DEBUG >= 4
    printf ("CLIENT: S9xCheckForHeartBeat %s @%ld\n", (i?"successful":"still waiting"), S9xGetMilliTime () - START);
#endif

    return i;
}

bool8 S9xNPWaitForHeartBeatDelay (uint32 time_msec)
{
    if (!S9xNPCheckForHeartBeat(time_msec))
        return FALSE;

    if (!S9xNPWaitForHeartBeat())
    {
        S9xNPDisconnect();
	return FALSE;
    }

    return TRUE;
}

bool8 S9xNPWaitForHeartBeat ()
{
    uint8 header [3 + 4 + 4 * 5];

    while (S9xNPGetData (NetPlay.Socket, header, 3 + 4))
    {
        if (header [0] != NP_SERV_MAGIC)
        {
            S9xNPSetError ("Bad magic value from server while waiting for heart-beat message\n");
            S9xNPDisconnect ();
            return (FALSE);
        }
        if (header [1] != NetPlay.ServerSequenceNum)
        {
            char buf [200];
            sprintf (buf, "Unexpected message sequence number from server, expected %d, got %d\n", NetPlay.ServerSequenceNum, header [1]);
            S9xNPSetWarning (buf);
            NetPlay.ServerSequenceNum = header [1] + 1;
        }
        else
            NetPlay.ServerSequenceNum++;

        if ((header [2] & 0x1f) == NP_SERV_JOYPAD)
        {
            // Top 2 bits + 1 of opcode is joypad data count.
            int num = (header [2] >> 6) + 1;

            if (num)
            {
                if (!S9xNPGetData (NetPlay.Socket, header + 3 + 4, num * 4))
                {
                    S9xNPSetError ("Error while receiving 'JOYPAD' message.");
                    S9xNPDisconnect ();
                    return (FALSE);
                }
            }
            NetPlay.Frame [NetPlay.JoypadWriteInd] = READ_LONG (&header [3]);

			int i;

			for (i = 0; i < num; i++)
                NetPlay.Joypads [NetPlay.JoypadWriteInd][i] = READ_LONG (&header [3 + 4 + i * sizeof (uint32)]);

			for (i = 0; i < NP_MAX_CLIENTS; i++)
				NetPlay.JoypadsReady [NetPlay.JoypadWriteInd][i] = TRUE;

			NetPlay.Paused = (header [2] & 0x20) != 0;

            NetPlay.JoypadWriteInd = (NetPlay.JoypadWriteInd + 1) % NP_JOYPAD_HIST_SIZE;

            if (NetPlay.JoypadWriteInd != (NetPlay.JoypadReadInd + 1) % NP_JOYPAD_HIST_SIZE)
            {
                //printf ("(%d)", (NetPlay.JoypadWriteInd - NetPlay.JoypadReadInd) % NP_JOYPAD_HIST_SIZE); fflush (stdout);
            }
//printf ("CLIENT: HB: @%d\n", S9xGetMilliTime () - START);
            return (TRUE);
        }
        else
        {
            uint32 len = READ_LONG (&header [3]);
	    switch (header [2] & 0x1f)
	    {
	    case NP_SERV_RESET:
#ifdef NP_DEBUG
                printf ("CLIENT: RESET received @%ld\n", S9xGetMilliTime () - START);
#endif
                S9xNPDiscardHeartbeats ();
		S9xReset ();
                NetPlay.FrameCount = READ_LONG (&header [3]);
                S9xNPResetJoypadReadPos ();
                S9xNPSendReady ();
                break;
	    case NP_SERV_PAUSE:
                NetPlay.Paused = (header [2] & 0x20) != 0;
				if (NetPlay.Paused)
					S9xNPSetWarning("CLIENT: Server has paused.");
				else
					S9xNPSetWarning("CLIENT: Server has resumed.");
                break;
            case NP_SERV_LOAD_ROM:
#ifdef NP_DEBUG
                printf ("CLIENT: LOAD_ROM received @%ld\n", S9xGetMilliTime () - START);
#endif
                S9xNPDiscardHeartbeats ();
                if (S9xNPLoadROM (len - 7))
                    S9xNPSendReady (NP_CLNT_LOADED_ROM);
                break;
            case NP_SERV_ROM_IMAGE:
#ifdef NP_DEBUG
                printf ("CLIENT: ROM_IMAGE received @%ld\n", S9xGetMilliTime () - START);
#endif
                S9xNPDiscardHeartbeats ();
                if (S9xNPGetROMImage (len - 7))
                    S9xNPSendReady (NP_CLNT_RECEIVED_ROM_IMAGE);
                break;
            case NP_SERV_SRAM_DATA:
#ifdef NP_DEBUG
                printf ("CLIENT: SRAM_DATA received @%ld\n", S9xGetMilliTime () - START);
#endif
                S9xNPDiscardHeartbeats ();
                S9xNPGetSRAMData (len - 7);
                break;
            case NP_SERV_FREEZE_FILE:
#ifdef NP_DEBUG
                printf ("CLIENT: FREEZE_FILE received @%ld\n", S9xGetMilliTime () - START);
#endif
                S9xNPDiscardHeartbeats ();
                S9xNPGetFreezeFile (len - 7);
                S9xNPResetJoypadReadPos ();
                S9xNPSendReady ();
                break;
            default:
#ifdef NP_DEBUG
                printf ("CLIENT: UNKNOWN received @%ld\n", S9xGetMilliTime () - START);
#endif
                S9xNPDisconnect ();
                return (FALSE);
	    }
	}
    }

    S9xNPDisconnect ();
    return (FALSE);
}

bool8 S9xNPLoadROMDialog (const char *rom_name)
{
    NetPlay.Answer = FALSE;

#ifdef __WIN32__
    ResetEvent (NetPlay.ReplyEvent);

#ifdef NP_DEBUG
    printf ("CLIENT: Asking GUI thread to open ROM load dialog...\n");
#endif

    PostMessage (GUI.hWnd, WM_USER + 3, (WPARAM) rom_name, (LPARAM) rom_name);

#ifdef NP_DEBUG
    printf ("CLIENT: Waiting for reply from GUI thread...\n");
#endif

    WaitForSingleObject (NetPlay.ReplyEvent, INFINITE);

#ifdef NP_DEBUG
    printf ("CLIENT: Got reply from GUI thread (%d)\n", NetPlay.Answer);
#endif

#else
	NetPlay.Answer = TRUE;
#endif

    return (NetPlay.Answer);
}

bool8 S9xNPLoadROM (uint32 len)
{
    uint8 *data = new uint8 [len];

    S9xNPSetAction ("Receiving ROM name...");
    if (!S9xNPGetData (NetPlay.Socket, data, len))
    {
        S9xNPSetError ("Error while receiving ROM name.");
        delete[] data;
        S9xNPDisconnect ();
        return (FALSE);
    }

    S9xNPSetAction ("Opening LoadROM dialog...");
    if (!S9xNPLoadROMDialog ((char *) data))
    {
        S9xNPSetError ("Disconnected from NetPlay server because you are playing a different game!");
        delete[] data;
        S9xNPDisconnect ();
        return (FALSE);
    }
    delete[] data;
    return (TRUE);
}

bool8 S9xNPGetROMImage (uint32 len)
{
    uint8 rom_info [5];

    S9xNPSetAction ("Receiving ROM information...");
    if (!S9xNPGetData (NetPlay.Socket, rom_info, 5))
    {
        S9xNPSetError ("Error while receiving ROM information.");
        S9xNPDisconnect ();
        return (FALSE);
    }
    uint32 CalculatedSize = READ_LONG (&rom_info [1]);
#ifdef NP_DEBUG
    printf ("CLIENT: Hi-ROM: %s, Size: %04x\n", rom_info [0] ? "Y" : "N", CalculatedSize);
#endif
    if (CalculatedSize + 5 >= len ||
        CalculatedSize >= CMemory::MAX_ROM_SIZE)
    {
        S9xNPSetError ("Size error in ROM image data received from server.");
        S9xNPDisconnect ();
        return (FALSE);
    }

    Memory.HiROM = rom_info [0];
    Memory.LoROM = !Memory.HiROM;
    Memory.HeaderCount = 0;
    Memory.CalculatedSize = CalculatedSize;

    // Load up ROM image
#ifdef NP_DEBUG
    printf ("CLIENT: Receiving ROM image @%ld...\n", S9xGetMilliTime () - START);
#endif
    S9xNPSetAction ("Receiving ROM image...");
    if (!S9xNPGetData (NetPlay.Socket, Memory.ROM, Memory.CalculatedSize))
    {
        S9xNPSetError ("Error while receiving ROM image from server.");
        Settings.StopEmulation = TRUE;
        S9xNPDisconnect ();
        return (FALSE);
    }
#ifdef NP_DEBUG
    printf ("CLIENT: Receiving ROM filename @%ld...\n", S9xGetMilliTime () - START);
#endif
    S9xNPSetAction ("Receiving ROM filename...");
    uint32 filename_len = len - Memory.CalculatedSize - 5;
    if (filename_len > PATH_MAX ||
        !S9xNPGetData (NetPlay.Socket, (uint8 *) Memory.ROMFilename, filename_len))
    {
        S9xNPSetError ("Error while receiving ROM filename from server.");
        S9xNPDisconnect ();
        Settings.StopEmulation = TRUE;
        return (FALSE);
    }
    Memory.InitROM ();
    S9xReset ();
    S9xNPResetJoypadReadPos ();
    Settings.StopEmulation = FALSE;

#ifdef __WIN32__
    PostMessage (GUI.hWnd, WM_NULL, 0, 0);
#endif

    return (TRUE);
}

void S9xNPGetSRAMData (uint32 len)
{
    if (len > 0x10000)
    {
        S9xNPSetError ("Length error in S-RAM data received from server.");
        S9xNPDisconnect ();
        return;
    }
    S9xNPSetAction ("Receiving S-RAM data...");
    if (len > 0 && !S9xNPGetData (NetPlay.Socket, Memory.SRAM, len))
    {
        S9xNPSetError ("Error while receiving S-RAM data from server.");
        S9xNPDisconnect ();
    }
	S9xNPSetAction ("", TRUE);
}

void S9xNPGetFreezeFile (uint32 len)
{
    uint8 frame_count [4];

#ifdef NP_DEBUG
    printf ("CLIENT: Receiving freeze file information @%ld...\n", S9xGetMilliTime () - START);
#endif
    S9xNPSetAction ("Receiving freeze file information...");
    if (!S9xNPGetData (NetPlay.Socket, frame_count, 4))
    {
        S9xNPSetError ("Error while receiving freeze file information from server.");
        S9xNPDisconnect ();
        return;
    }
    NetPlay.FrameCount = READ_LONG (frame_count);

#ifdef NP_DEBUG
    printf ("CLIENT: Receiving freeze file @%ld...\n", S9xGetMilliTime () - START);
#endif
    S9xNPSetAction ("Receiving freeze file...");
    uint8 *data = new uint8 [len];
    if (!S9xNPGetData (NetPlay.Socket, data, len - 4))
    {
        S9xNPSetError ("Error while receiving freeze file from server.");
        S9xNPDisconnect ();
        delete[] data;
        return;
    }
	S9xNPSetAction ("", TRUE);

    //FIXME: Setting umask here wouldn't hurt.
    FILE *file;
#ifdef HAVE_MKSTEMP
    int fd;
    char fname[] = "/tmp/snes9x_fztmpXXXXXX";
    if ((fd = mkstemp(fname)) >= 0)
    {
        if ((file = fdopen (fd, "wb")))
#else
    char fname [L_tmpnam];
    if (tmpnam (fname))
    {
        if ((file = fopen (fname, "wb")))
#endif
        {
            if (fwrite (data, 1, len, file) == len)
            {
                fclose(file);
#ifndef __WIN32__
		/* We need .s96 extension, else .s96 is addded by unix code */
                char buf[PATH_MAX +1 ];

                strncpy(buf, fname, PATH_MAX);
                strcat(buf, ".s96");

                rename(fname, buf);

                if (!S9xUnfreezeGame (buf))
#else
                if (!S9xUnfreezeGame (fname))
#endif
                    S9xNPSetError ("Unable to load freeze file just received.");
            } else {
                S9xNPSetError ("Failed to write to temporary freeze file.");
                fclose(file);
            }
        } else
            S9xNPSetError ("Failed to create temporary freeze file.");
        remove (fname);
    } else
        S9xNPSetError ("Unable to get name for temporary freeze file.");
    delete[] data;
}

uint32 S9xNPGetJoypad (int which1)
{
    if (Settings.NetPlay && which1 < 8)
	{
#ifdef NP_DEBUG
		if(!NetPlay.JoypadsReady [NetPlay.JoypadReadInd][which1])
		{
            S9xNPSetWarning ("Missing input from server!");
		}
#endif
		NetPlay.JoypadsReady [NetPlay.JoypadReadInd][which1] = FALSE;

		return (NetPlay.Joypads [NetPlay.JoypadReadInd][which1]);
	}

    return (0);
}

void S9xNPStepJoypadHistory ()
{
    if ((NetPlay.JoypadReadInd + 1) % NP_JOYPAD_HIST_SIZE != NetPlay.JoypadWriteInd)
    {
        NetPlay.JoypadReadInd = (NetPlay.JoypadReadInd + 1) % NP_JOYPAD_HIST_SIZE;
        if (NetPlay.FrameCount != NetPlay.Frame [NetPlay.JoypadReadInd])
        {
            S9xNPSetWarning ("This Snes9x session may be out of sync with the server.");
#ifdef NP_DEBUG
            printf ("*** CLIENT: client out of sync with server (%d, %d) @%ld\n", NetPlay.FrameCount, NetPlay.Frame [NetPlay.JoypadReadInd], S9xGetMilliTime () - START);
#endif
        }
    }
    else
    {
#ifdef NP_DEBUG
        printf ("*** CLIENT: S9xNPStepJoypadHistory NOT OK@%ld\n", S9xGetMilliTime () - START);
#endif
    }
}


void S9xNPResetJoypadReadPos ()
{
#ifdef NP_DEBUG
    printf ("CLIENT: ResetJoyReadPos @%ld\n", S9xGetMilliTime () - START); fflush (stdout);
#endif
    NetPlay.JoypadWriteInd = 0;
    NetPlay.JoypadReadInd = NP_JOYPAD_HIST_SIZE - 1;
    for (int h = 0; h < NP_JOYPAD_HIST_SIZE; h++)
        memset ((void *) &NetPlay.Joypads [h], 0, sizeof (NetPlay.Joypads [0]));
    for (int h = 0; h < NP_JOYPAD_HIST_SIZE; h++)
        memset ((void *) &NetPlay.JoypadsReady [h], 0, sizeof (NetPlay.JoypadsReady [0]));
}

bool8 S9xNPSendJoypadUpdate (uint32 joypad)
{
    uint8 data [7];
    uint8 *ptr = data;

    *ptr++ = NP_CLNT_MAGIC;
    *ptr++ = NetPlay.MySequenceNum++;
    *ptr++ = NP_CLNT_JOYPAD;

    joypad |= 0x80000000;

    WRITE_LONG (ptr, joypad);
    if (!S9xNPSendData (NetPlay.Socket, data, 7))
    {
        S9xNPSetError ("Error while sending joypad data server.");
	S9xNPDisconnect ();
	return (FALSE);
    }
    return (TRUE);
}

void S9xNPDisconnect ()
{
    close (NetPlay.Socket);
    NetPlay.Socket = -1;
    NetPlay.Connected = FALSE;
    Settings.NetPlay = FALSE;
}

bool8 S9xNPSendData (int socket, const uint8 *data, int length)
{
    int len = length;
    const uint8 *ptr = data;

    NetPlay.PercentageComplete = 0;

    do
    {
        if (NetPlay.Abort)
            return (FALSE);

        int num_bytes = len;

        // Write the data in small chunks, allowing this thread to spot an
        // abort request from another thread.
        if (num_bytes > 512)
            num_bytes = 512;

	int sent = write (socket, (char *) ptr, num_bytes);
	if (sent < 0)
	{
	    if (errno == EINTR
#ifdef EAGAIN
		|| errno == EAGAIN
#endif
#ifdef EWOULDBLOCK
		|| errno == EWOULDBLOCK
#endif
		)
            {
#ifdef NP_DEBUG
                printf ("CLIENT: EINTR, EAGAIN or EWOULDBLOCK while sending data @%ld\n", S9xGetMilliTime () - START);
#endif
		continue;
            }
	    return (FALSE);
	}
	else
	if (sent == 0)
	    return (FALSE);
	len -= sent;
	ptr += sent;

        NetPlay.PercentageComplete = (uint8) (((length - len) * 100) / length);
    } while (len > 0);

    return (TRUE);
}

bool8 S9xNPGetData (int socket, uint8 *data, int length)
{
    int len = length;
    uint8 *ptr = data;
    int chunk = length / 50;

    if (chunk < 1024)
        chunk = 1024;

    NetPlay.PercentageComplete = 0;
    do
    {
        if (NetPlay.Abort)
            return (FALSE);

        int num_bytes = len;

        // Read the data in small chunks, allowing this thread to spot an
        // abort request from another thread.
        if (num_bytes > chunk)
            num_bytes = chunk;

        int got = read (socket, (char *) ptr, num_bytes);
        if (got < 0)
        {
	    if (errno == EINTR
#ifdef EAGAIN
		|| errno == EAGAIN
#endif
#ifdef EWOULDBLOCK
		|| errno == EWOULDBLOCK
#endif
#ifdef WSAEWOULDBLOCK
                || errno == WSAEWOULDBLOCK
#endif
		)
            {
#ifdef NP_DEBUG
                printf ("CLIENT: EINTR, EAGAIN or EWOULDBLOCK while receiving data @%ld\n", S9xGetMilliTime () - START);
#endif
		continue;
            }
#ifdef WSAEMSGSIZE
            if (errno != WSAEMSGSIZE)
                return (FALSE);
            else
            {
                got = num_bytes;
#ifdef NP_DEBUG
                printf ("CLIENT: WSAEMSGSIZE, actual bytes %d while receiving data @%ld\n", got, S9xGetMilliTime () - START);
#endif
            }
#else
            return (FALSE);
#endif
        }
        else
        if (got == 0)
            return (FALSE);

        len -= got;
        ptr += got;

        if (!Settings.NetPlayServer && length > 1024)
        {
            NetPlay.PercentageComplete = (uint8) (((length - len) * 100) / length);
#ifdef __WIN32__
            PostMessage (GUI.hWnd, WM_USER, NetPlay.PercentageComplete,
                         NetPlay.PercentageComplete);
            Sleep (0);
#endif
        }

    } while (len > 0);

    return (TRUE);
}

bool8 S9xNPInitialise ()
{
#ifdef __WIN32__
    static bool8 initialised = FALSE;

    if (!initialised)
    {
        initialised = TRUE;
        WSADATA data;

#ifdef NP_DEBUG
        START = S9xGetMilliTime ();

        printf ("CLIENT/SERVER: Initialising WinSock @%ld\n", S9xGetMilliTime () - START);
#endif
        S9xNPSetAction ("Initialising Windows sockets interface...");
        if (WSAStartup (MAKEWORD (1, 0), &data) != 0)
        {
            S9xNPSetError ("Call to init Windows sockets failed. Do you have WinSock2 installed?");
            return (FALSE);
        }
    }
#endif
    return (TRUE);
}

void S9xNPDiscardHeartbeats ()
{
    // Discard any pending heartbeats and wait for any frame that is currently
    // being emulated to complete.
#ifdef NP_DEBUG
    printf ("CLIENT: DiscardHeartbeats @%ld, finished @", S9xGetMilliTime () - START);
    fflush (stdout);
#endif

#ifdef __WIN32__
    while (WaitForSingleObject (GUI.ClientSemaphore, 200) == WAIT_OBJECT_0)
        ;
#endif

#ifdef NP_DEBUG
    printf ("%ld\n", S9xGetMilliTime () - START);
#endif
    NetPlay.Waiting4EmulationThread = FALSE;
}

void S9xNPSetAction (const char *action, bool8 force)
{
#ifdef NP_DEBUG
    printf ("NPSetAction: %s, forced = %d %ld\n", action, force, S9xGetMilliTime () - START);
#endif
    if (force || !Settings.NetPlayServer)
    {
        strncpy (NetPlay.ActionMsg, action, NP_MAX_ACTION_LEN - 1);
        NetPlay.ActionMsg [NP_MAX_ACTION_LEN - 1] = 0;
#ifdef __WIN32__
        PostMessage (GUI.hWnd, WM_USER, 0, 0);
        Sleep (0);
#endif
    }
}

void S9xNPSetError (const char *error)
{
#if defined(NP_DEBUG) && NP_DEBUG == 2
    printf("ERROR: %s\n", error);
    fflush (stdout);
#endif
    strncpy (NetPlay.ErrorMsg, error, NP_MAX_ACTION_LEN - 1);
    NetPlay.ErrorMsg [NP_MAX_ACTION_LEN - 1] = 0;
#ifdef __WIN32__
    PostMessage (GUI.hWnd, WM_USER + 1, 0, 0);
    Sleep (0);
#endif
}

void S9xNPSetWarning (const char *warning)
{
#if defined(NP_DEBUG) && NP_DEBUG == 3
    printf("Warning: %s\n", warning);
    fflush (stdout);
#endif
    strncpy (NetPlay.WarningMsg, warning, NP_MAX_ACTION_LEN - 1);
    NetPlay.WarningMsg [NP_MAX_ACTION_LEN - 1] = 0;
#ifdef __WIN32__
    PostMessage (GUI.hWnd, WM_USER + 2, 0, 0);
    Sleep (0);
#endif
}
#endif