AcessNative/acesskernel_src/server.c

   1 /*
   2  * Acess2 Native Kernel
   3  * - Acess kernel emulation on another OS using SDL and UDP
   4  *
   5  * Syscall Server
   6  */
   7 #include <stdio.h>
   8 #include <stdlib.h>
   9 #include <string.h>
  10 #include <SDL/SDL.h>
  11 #ifdef __WIN32__
  12 # include <windows.h>
  13 # include <winsock.h>
  14 #else
  15 # include <unistd.h>
  16 # include <sys/socket.h>
  17 # include <netinet/in.h>
  18 #endif
  19 #include "../syscalls.h"
  20
  21 #define USE_TCP 0
  22 #define MAX_CLIENTS     16
  23
  24 // === TYPES ===
  25 typedef struct {
  26          int    ClientID;
  27         SDL_Thread      *WorkerThread;
  28         #if USE_TCP
  29         #else
  30         tRequestHeader  *CurrentRequest;
  31         struct sockaddr_in      ClientAddr;
  32         SDL_cond        *WaitFlag;
  33         SDL_mutex       *Mutex;
  34         #endif
  35 }       tClient;
  36
  37 // === IMPORTS ===
  38 extern tRequestHeader *SyscallRecieve(tRequestHeader *Request, int *ReturnLength);
  39
  40 // === PROTOTYPES ===
  41 tClient *Server_GetClient(int ClientID);
  42  int    Server_WorkerThread(void *ClientPtr);
  43  int    SyscallServer(void);
  44
  45 // === GLOBALS ===
  46 #ifdef __WIN32__
  47 WSADATA gWinsock;
  48 SOCKET  gSocket = INVALID_SOCKET;
  49 #else
  50 # define INVALID_SOCKET -1
  51  int    gSocket = INVALID_SOCKET;
  52 #endif
  53  int    giServer_NextClientID = 1;
  54 tClient gaServer_Clients[MAX_CLIENTS];
  55
  56 // === CODE ===
  57 int Server_GetClientID(void)
  58 {
  59          int    i;
  60         Uint32  thisId = SDL_ThreadID();
  61
  62         for( i = 0; i < MAX_CLIENTS; i ++ )
  63         {
  64                 if( SDL_GetThreadID(gaServer_Clients[i].WorkerThread) == thisId )
  65                         return gaServer_Clients[i].ClientID;
  66         }
  67
  68         fprintf(stderr, "ERROR: Server_GetClientID - Thread is not allocated\n");
  69
  70         return 0;
  71 }
  72
  73 tClient *Server_GetClient(int ClientID)
  74 {
  75         tClient *ret = NULL;
  76          int    i;
  77
  78         for( i = 0; i < MAX_CLIENTS; i ++ )
  79         {
  80                 if( gaServer_Clients[i].ClientID == ClientID ) {
  81                         ret = &gaServer_Clients[i];
  82                         break;
  83                 }
  84         }
  85
  86         // Uh oh, no free slots
  87         // TODO: Dynamic allocation
  88         if( !ret )
  89                 return NULL;
  90
  91         if( ClientID == 0 )
  92         {
  93                 ret->ClientID = giServer_NextClientID ++;
  94                 ret->CurrentRequest = NULL;
  95
  96                 if( !ret->WorkerThread ) {
  97                         ret->WaitFlag = SDL_CreateCond();
  98                         ret->Mutex = SDL_CreateMutex();
  99                         SDL_mutexP( ret->Mutex );
 100                         ret->WorkerThread = SDL_CreateThread( Server_WorkerThread, ret );
 101                 }
 102         }
 103
 104         return &gaServer_Clients[i];
 105 }
 106
 107 int Server_WorkerThread(void *ClientPtr)
 108 {
 109         tClient *Client = ClientPtr;
 110         tRequestHeader  *retHeader;
 111         tRequestHeader  errorHeader;
 112          int    retSize = 0;
 113          int    sentSize;
 114
 115         #if USE_TCP
 116         #else
 117         for( ;; )
 118         {
 119                 // Wait for something to do
 120                 while( Client->CurrentRequest == NULL )
 121                         SDL_CondWait(Client->WaitFlag, Client->Mutex);
 122
 123                 printf("Worker for %i, Job: %p\n", Client->ClientID, Client->CurrentRequest);
 124
 125                 // Get the response
 126                 retHeader = SyscallRecieve(Client->CurrentRequest, &retSize);
 127
 128                 if( !retHeader ) {
 129                         // Return an error to the client
 130                         printf("Error returned by SyscallRecieve\n");
 131                         errorHeader.CallID = Client->CurrentRequest->CallID;
 132                         errorHeader.NParams = 0;
 133                         retHeader = &errorHeader;
 134                         retSize = sizeof(errorHeader);
 135                 }
 136
 137                 // Set ID
 138                 retHeader->ClientID = Client->ClientID;
 139
 140                 // Mark the thread as ready for another job
 141                 Client->CurrentRequest = 0;
 142
 143                 printf("Sending %i to %x:%i\n",
 144                         retSize, ntohl(Client->ClientAddr.sin_addr.s_addr),
 145                         ntohs(Client->ClientAddr.sin_port)
 146                         );
 147
 148                 // Return the data
 149                 sentSize = sendto(gSocket, retHeader, retSize, 0,
 150                         (struct sockaddr*)&Client->ClientAddr, sizeof(Client->ClientAddr)
 151                         );
 152                 if( sentSize != retSize ) {
 153                         perror("Server_WorkerThread - send");
 154                 }
 155
 156                 // Free allocated header
 157                 if( retHeader != &errorHeader )
 158                         free( retHeader );
 159         }
 160         #endif
 161 }
 162
 163 int SyscallServer(void)
 164 {
 165         struct sockaddr_in      server;
 166
 167         #ifdef __WIN32__
 168         /* Open windows connection */
 169         if (WSAStartup(0x0101, &gWinsock) != 0)
 170         {
 171                 fprintf(stderr, "Could not open Windows connection.\n");
 172                 exit(0);
 173         }
 174         #endif
 175
 176         #if USE_TCP
 177         // Open TCP Connection
 178         gSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
 179         #else
 180         // Open UDP Connection
 181         gSocket = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
 182         #endif
 183         if (gSocket == INVALID_SOCKET)
 184         {
 185                 fprintf(stderr, "Could not create socket.\n");
 186                 #if __WIN32__
 187                 WSACleanup();
 188                 #endif
 189                 exit(0);
 190         }
 191
 192         // Set server address
 193         memset(&server, 0, sizeof(struct sockaddr_in));
 194         server.sin_family = AF_INET;
 195         server.sin_port = htons(SERVER_PORT);
 196         server.sin_addr.s_addr = htonl(INADDR_ANY);
 197
 198         // Bind
 199         if( bind(gSocket, (struct sockaddr *)&server, sizeof(struct sockaddr_in)) == -1 )
 200         {
 201                 fprintf(stderr, "Cannot bind address to socket.\n");
 202                 perror("SyscallServer - bind");
 203                 #if __WIN32__
 204                 closesocket(gSocket);
 205                 WSACleanup();
 206                 #else
 207                 close(gSocket);
 208                 #endif
 209                 exit(0);
 210         }
 211
 212         #if USE_TCP
 213         listen(gSocket, 5);
 214         #endif
 215
 216         Log_Notice("Syscall", "Listening on 0.0.0.0:%i\n", SERVER_PORT);
 217
 218         // Wait for something to do :)
 219         for( ;; )
 220         {
 221                 #if USE_TCP
 222                 struct sockaddr_in      client;
 223                 uint    clientSize = sizeof(client);
 224                  int    clientSock = accept(gSocket, (struct sockaddr*)&client, &clientSize);
 225                 if( clientSock < 0 ) {
 226                         perror("SyscallServer - accept");
 227                         break ;
 228                 }
 229
 230                 printf("Client connection %x:%i",
 231                         ntohl(client.sin_addr), ntohs(client.sin_port)
 232                         );
 233
 234                 #else
 235                 char    data[BUFSIZ];
 236                 tRequestHeader  *req = (void*)data;
 237                 struct sockaddr_in      addr;
 238                 uint    clientSize = sizeof(addr);
 239                  int    length = recvfrom(gSocket, data, BUFSIZ, 0, (struct sockaddr*)&addr, &clientSize);
 240                 tClient *client;
 241
 242                 if( length == -1 ) {
 243                         perror("SyscallServer - recv");
 244                         break;
 245                 }
 246
 247                 // Hand off to a worker thread
 248                 // - TODO: Actually have worker threads
 249                 printf("%i bytes from %x:%i\n", length,
 250                         ntohl(addr.sin_addr.s_addr), ntohs(addr.sin_port));
 251
 252                 client = Server_GetClient(req->ClientID);
 253                 if( req->ClientID == 0 )
 254                 {
 255                         memcpy(&client->ClientAddr, &addr, sizeof(addr));
 256                 }
 257                 else if( memcmp(&client->ClientAddr, &addr, sizeof(addr)) != 0 )
 258                 {
 259                         printf("ClientID %i used by %x:%i\n",
 260                                 client->ClientID, ntohl(addr.sin_addr.s_addr), ntohs(addr.sin_port));
 261                         printf(" actually owned by %x:%i\n",
 262                                 ntohl(client->ClientAddr.sin_addr.s_addr), ntohs(client->ClientAddr.sin_port));
 263                         continue;
 264                 }
 265
 266                 if( client->CurrentRequest ) {
 267                         printf("Worker thread for %x:%i is busy\n",
 268                                 ntohl(client->ClientAddr.sin_addr.s_addr), ntohs(client->ClientAddr.sin_port));
 269                         continue;
 270                 }
 271
 272                 printf("client = %p, ClientID = %i\n", client, client->ClientID);
 273
 274                 client->CurrentRequest = req;
 275                 SDL_CondSignal(client->WaitFlag);
 276                 #endif
 277         }
 278
 279         return -1;
 280 }