server.cpp

著名SFC模拟器Snes9x的源代码。

/*
 * Snes9x - Portable Super Nintendo Entertainment System (TM) emulator.
 *
 * (c) Copyright 1996 - 2001 Gary Henderson ([e-mail]) and
 *                           Jerremy Koot ([e-mail])
 *
 * Super FX C emulator code 
 * (c) Copyright 1997 - 1999 Ivar ([e-mail]) and
 *                           Gary Henderson.
 * Super FX assembler emulator code (c) Copyright 1998 zsKnight and _Demo_.
 *
 * DSP1 emulator code (c) Copyright 1998 Ivar, _Demo_ and Gary Henderson.
 * C4 asm and some C emulation code (c) Copyright 2000 zsKnight and _Demo_.
 * C4 C code (c) Copyright 2001 Gary Henderson ([e-mail]).
 *
 * DOS port code contains the works of other authors. See headers in
 * individual files.
 *
 * Snes9x homepage: www.snes9x.com
 *
 * Permission to use, copy, modify and distribute Snes9x in both binary and
 * source form, for non-commercial purposes, is hereby granted without fee,
 * providing that this license information and copyright notice appear with
 * all copies and any derived work.
 *
 * This software is provided 'as-is', without any express or implied
 * warranty. In no event shall the authors be held liable for any damages
 * arising from the use of this software.
 *
 * Snes9x is freeware for PERSONAL USE only. Commercial users should
 * seek permission of the copyright holders first. Commercial use includes
 * charging money for Snes9x or software derived from Snes9x.
 *
 * The copyright holders request that bug fixes and improvements to the code
 * should be forwarded to them so everyone can benefit from the modifications
 * in future versions.
 *
 * Super NES and Super Nintendo Entertainment System are trademarks of
 * Nintendo Co., Limited and its subsidiary companies.
 */
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <memory.h>
#include <sys/types.h>

#ifndef __WIN32__
#include <unistd.h>
#include <sys/time.h>
#endif

#ifdef __WIN32__

#include <winsock.h>
#include <process.h>
#define ioctl ioctlsocket
#define close closesocket
#define read(a,b,c) recv(a, b, c, 0)
#define write(a,b,c) send(a, b, c, 0)
#define gettimeofday(a,b) S9xGetTimeOfDay (a)
#define exit(a) _endthread()
void S9xGetTimeOfDay (struct timeval *n);
#else

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

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

#endif // !__WIN32__

#include "snes9x.h"
#include "netplay.h"
#include "memmap.h"
#include "snapshot.h"

#define NP_ONE_CLIENT 1

struct SNPServer NPServer;

extern unsigned long START;

void S9xNPSendToAllClients (uint8 *data, int len);
bool8 S9xNPLoadFreezeFile (const char *fname, uint8 *&data, uint32 &len);
void S9xNPSendFreezeFile (int c, uint8 *data, uint32 len);
void S9xNPNoClientReady (int start_index = NP_ONE_CLIENT);
void S9xNPRecomputePause ();
void S9xNPWaitForEmulationToComplete ();
void S9xNPSendROMImageToAllClients ();
bool8 S9xNPSendROMImageToClient (int client);
void S9xNPSendSRAMToClient (int c);
void S9xNPSendSRAMToAllClients ();
void S9xNPSyncClient (int);
void S9xNPSendROMLoadRequest (const char *filename);
void S9xNPSendFreezeFileToAllClients (const char *filename);
void S9xNPStopServer ();

void S9xNPShutdownClient (int c, bool8 report_error = FALSE)
{
    if (NPServer.Clients [c].Connected)
    {
        NPServer.Clients [c].Connected = FALSE;
        NPServer.Clients [c].SaidHello = FALSE;

        close (NPServer.Clients [c].Socket);
#ifdef NP_DEBUG
        printf ("SERVER: Player %d disconnecting @%ld\n", c + 1, S9xGetMilliTime () - START);
#endif
        if (report_error)
        {
            sprintf (NetPlay.ErrorMsg, 
                     "Player %d on '%s' has disconnected.", c + 1,
                     NPServer.Clients [c].HostName);
            S9xNPSetError (NetPlay.ErrorMsg);
        }

        if (NPServer.Clients [c].HostName)
        {
            free ((char *) NPServer.Clients [c].HostName);
            NPServer.Clients [c].HostName = NULL;
        }
        if (NPServer.Clients [c].ROMName)
        {
            free ((char *) NPServer.Clients [c].ROMName);
            NPServer.Clients [c].ROMName = NULL;
        }
        if (NPServer.Clients [c].Who)
        {
            free ((char *) NPServer.Clients [c].Who);
            NPServer.Clients [c].Who = NULL;
        }
        NPServer.Joypads [c] = 0;
        NPServer.NumClients--;
        S9xNPRecomputePause ();
    }
}

static bool8 S9xNPSGetData (int socket, uint8 *data, int length)
{
    int len = length;
    uint8 *ptr = data;

    do
    {
        int num_bytes = len;

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

        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
		)
		continue;
#ifdef WSAEMSGSIZE
            if (errno != WSAEMSGSIZE)
                return (FALSE);
            else
            {
                got = num_bytes;
#ifdef NP_DEBUG
                printf ("SERVER: WSAEMSGSIZE, actual bytes %d while receiving data @%d\n", got, S9xGetMilliTime () - START);
#endif
            }
#else
            return (FALSE);
#endif
        }
        else
        if (got == 0)
            return (FALSE);

        len -= got;
        ptr += got;
    } while (len > 0);

    return (TRUE);
}

static bool8 S9xNPSSendData (int fd, const uint8 *data, int length)
{
    int Percent = 0;
    int len = length;
    int chunk = length / 50;

    if (chunk < 1024)
        chunk = 1024;
    
    do
    {
        int num_bytes = len;

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

	int sent;
	sent = write (fd, (char *) data, len);

	if (sent < 0)
	{
	    if (errno == EINTR 
#ifdef EAGAIN
		|| errno == EAGAIN
#endif
#ifdef EWOULDBLOCK
		|| errno == EWOULDBLOCK
#endif
		)
            {
#ifdef NP_DEBUG
                printf ("SERVER: EINTR, EAGAIN or EWOULDBLOCK while sending data @%ld\n", S9xGetMilliTime () - START);
#endif
		continue;
            }
	    return (FALSE);
	}
	else
	if (sent == 0)
	    return (FALSE);
	len -= sent;
	data += sent;
        if (length > 1024)
        {
            Percent = (uint8) (((length - len) * 100) / length);
#ifdef __WIN32__
            PostMessage (GUI.hWnd, WM_USER, Percent, Percent);
            Sleep (0);
#endif
        }
    } while (len > 0);

    return (TRUE);
}

void S9xNPSendHeartBeat ()
{
    int len = 3;
    uint8 data [3 + 4 * 5];
    uint8 *ptr = data;
    int n;

    for (n = NP_MAX_CLIENTS - 1; n >= 0; n--)
    {
        if (NPServer.Clients [n].SaidHello)
            break;
    }

    if (n >= 0)
    {
        bool8 Paused = NPServer.Paused != 0;
        
        NPServer.FrameCount++;
        *ptr++ = NP_SERV_MAGIC;
        *ptr++ = 0; // Individual client sequence number will get placed here
        *ptr++ = NP_SERV_JOYPAD | (n << 6) | ((Paused != 0) << 5);
        
        WRITE_LONG (ptr, NPServer.FrameCount);
        len += 4;
        ptr += 4;

        int i;
        
        for (i = 0; i <= n; i++)
        {
            WRITE_LONG (ptr, NPServer.Joypads [i]);
            len += 4;
            ptr += 4;
        }

        S9xNPSendToAllClients (data, len);
    }
}

void S9xNPSendToAllClients (uint8 *data, int len)
{
    int i;

    for (i = 0; i < NP_MAX_CLIENTS; i++)
    {
	if (NPServer.Clients [i].SaidHello)
	{
            data [1] = NPServer.Clients [i].SendSequenceNum++;
	    if (!S9xNPSSendData (NPServer.Clients [i].Socket, data, len))
		S9xNPShutdownClient (i, TRUE);
	}
    }
}

void S9xNPProcessClient (int c)
{
    uint8 header [7];
    uint8 *data;
    uint32 len;
    uint8 *ptr;

    if (!S9xNPSGetData (NPServer.Clients [c].Socket, header, 7))
    {
        S9xNPSetWarning ("SERVER: Failed to get message header from client.\n");
        S9xNPShutdownClient (c, TRUE);
        return;
    }
    if (header [0] != NP_CLNT_MAGIC)
    {
        S9xNPSetWarning ("SERVER: Bad header magic value received from client.\n");
        S9xNPShutdownClient (c, TRUE);
        return;
    }

    if (header [1] != NPServer.Clients [c].ReceiveSequenceNum)
    {
#ifdef NP_DEBUG
        printf ("SERVER: Messages lost from '%s', expected %d, got %d\n",
                NPServer.Clients [c].HostName ? 
                NPServer.Clients [c].HostName : "Unknown", 
                NPServer.Clients [c].ReceiveSequenceNum,
                header [1]);
#endif
        sprintf (NetPlay.WarningMsg, 
                 "SERVER: Messages lost from '%s', expected %d, got %d\n",
                NPServer.Clients [c].HostName ? 
                NPServer.Clients [c].HostName : "Unknown", 
                NPServer.Clients [c].ReceiveSequenceNum,
                header [1]);
        NPServer.Clients [c].ReceiveSequenceNum = header [1] + 1;
        S9xNPSetWarning (NetPlay.WarningMsg);
    }
    else
        NPServer.Clients [c].ReceiveSequenceNum++;

    len = READ_LONG (&header [3]);

    switch (header [2] & 0x3f)
    {
        case NP_CLNT_HELLO:
#ifdef NP_DEBUG
            printf ("SERVER: Got HELLO from client @%ld\n", S9xGetMilliTime () - START);
#endif
            S9xNPSetAction ("Got HELLO from client...", TRUE);
            if (len > 0x10000)
            {
                S9xNPSetWarning ("SERVER: Client HELLO message length error.");
                S9xNPShutdownClient (c, TRUE);
                return;
            }
            data = new uint8 [len - 7];
            if (!S9xNPSGetData (NPServer.Clients [c].Socket, data, len - 7))
            {
                S9xNPSetWarning ("SERVER: Failed to get HELLO message content from client.");
                S9xNPShutdownClient (c, TRUE);
                return;
            }

            if (NPServer.NumClients <= NP_ONE_CLIENT)
            {
		NPServer.FrameTime = READ_LONG (data);
		strncpy (NPServer.ROMName, (char *) &data [4], 29);
		NPServer.ROMName [29] = 0;
            }

            NPServer.Clients [c].ROMName = strdup ((char *) &data [4]);
#ifdef NP_DEBUG
            printf ("SERVER: Client is playing: %s, Frame Time: %d @%ld\n", data + 4, READ_LONG (data), S9xGetMilliTime () - START);
#endif

            NPServer.Clients [c].SendSequenceNum = 0;

            len = 7 + 1 + 1 + 4 + strlen (NPServer.ROMName) + 1;

            delete data;
            ptr = data = new uint8 [len];
            *ptr++ = NP_SERV_MAGIC;
            *ptr++ = NPServer.Clients [c].SendSequenceNum++;

            if (NPServer.SendROMImageOnConnect && 
                NPServer.NumClients > NP_ONE_CLIENT)
                *ptr++ = NP_SERV_HELLO | 0x80;
            else
                *ptr++ = NP_SERV_HELLO;
            WRITE_LONG (ptr, len);
            ptr += 4;
            *ptr++ = NP_VERSION;
            *ptr++ = c + 1;
            WRITE_LONG (ptr, NPServer.FrameCount);
            ptr += 4;
            strcpy ((char *) ptr, NPServer.ROMName);

#ifdef NP_DEBUG
            printf ("SERVER: Sending welcome information to client @%ld...\n", S9xGetMilliTime () - START);
#endif
            S9xNPSetAction ("SERVER: Sending welcome information to new client...", TRUE);
            if (!S9xNPSSendData (NPServer.Clients [c].Socket, data, len))
            {
                S9xNPSetWarning ("SERVER: Failed to send welcome message to client.");
                S9xNPShutdownClient (c, TRUE);
                return;