Usermode/Applications/telnetd_src/main.c

   1 /*
   2  */
   3 #include <stddef.h>
   4 #include <net.h>
   5 #include <unistd.h>
   6 #include <stdio.h>
   7
   8 // === TYPES ===
   9 typedef struct sClient
  10 {
  11          int    Socket;
  12          int    stdout;
  13          int    stdin;
  14 } tClient;
  15
  16 // === PROTOTYPES ===
  17 void    EventLoop(void);
  18 void    Server_NewClient(int FD);
  19 void    HandleServerBoundData(tClient *Client);
  20 void    HandleClientBoundData(tClient *Client);
  21
  22 // === GLOBALS ===
  23 // --- Configuration ---
  24  int    giConfig_MaxClients = 5;
  25 // --- State ---
  26  int    giServerFD;
  27 tClient *gaClients;
  28  int    giNumClients;
  29
  30 // === CODE ===
  31 int main(int argc, char *argv[])
  32 {
  33         // TODO: Configure
  34
  35         // Initialise
  36         gaClients = calloc(giConfig_MaxClients, sizeof(tClient));
  37
  38         // Open server
  39         giServerFD = Net_OpenSocket(0, NULL, "tcps");
  40
  41         // Event loop
  42         EventLoop();
  43
  44         return 0;
  45 }
  46
  47 void EventLoop(void)
  48 {
  49         fd_set  fds;
  50          int    maxfd;
  51
  52         void FD_SET_MAX(fd_set *set, int fd, int *maxfd)
  53         {
  54                 FD_SET(fd, set);
  55                 if(*maxfd < fd) *maxfd = fd;
  56         }
  57
  58         for( ;; )
  59         {
  60                 maxfd = 0;
  61                 // Fill select
  62                 FD_SET_MAX(&fds, giServerFD, &maxfd);
  63                 for( int i = 0; i < giConfig_MaxClients; i ++ )
  64                 {
  65                         FD_SET_MAX(&fds, gaClients[i].Socket, &maxfd);
  66                         FD_SET_MAX(&fds, gaClients[i].stdout,  &maxfd);
  67                 }
  68
  69                 // Select!
  70                 select( maxfd+1, &fds, NULL, NULL, NULL );
  71
  72                 // Check events
  73                 if( FD_ISSET(giServerFD, &fds) )
  74                 {
  75                         Server_NewClient(giServerFD);
  76                 }
  77                 for( int i = 0; i < giConfig_MaxClients; i ++ )
  78                 {
  79                         if( FD_ISSET(gaClients[i].Socket, &fds) )
  80                         {
  81                                 // Handle client data
  82                                 HandleServerBoundData(&gaClients[i]);
  83                         }
  84                         if( FD_ISSET(gaClients[i].stdout, &fds) )
  85                         {
  86                                 // Handle output from terminal
  87                                 HandleClientBoundData(&gaClients[i]);
  88                         }
  89                 }
  90         }
  91 }
  92
  93 void Server_NewClient(int FD)
  94 {
  95         tClient *clt;
  96
  97         // TODO: Is this done in the IPStack?
  98         if( giNumClients == giConfig_MaxClients )
  99         {
 100                 // Open, reject
 101                 close( _SysOpenChild(FD, "", O_RDWR) );
 102                 return ;
 103         }
 104
 105         // Allocate client structure and open socket
 106         for( int i = 0; i < giConfig_MaxClients; i ++ )
 107         {
 108                 if( gaClients[i].Socket == 0 ) {
 109                         clt = &gaClients[i];
 110                         break;
 111                 }
 112         }
 113         // Accept the connection
 114         clt->Socket = _SysOpenChild(FD, "", O_RDWR);
 115         giNumClients ++;
 116
 117         // Create stdin/stdout
 118         clt->stdin = open("/Devices/fifo", O_RDWR);
 119         clt->stdout = open("/Devices/fifo", O_RDWR);
 120
 121         // TODO: Arguments and envp
 122         {
 123                 int fds[3] = {clt->stdin, clt->stdout, clt->stdout};
 124                 _SysSpawn("/Acess/SBin/login", NULL, NULL, 3, fds);
 125         }
 126 }
 127
 128 void HandleServerBoundData(tClient *Client)
 129 {
 130         char    buf[BUFSIZ];
 131          int    len;
 132
 133         len = read(Client->Socket, buf, BUFSIZ);
 134         write(Client->stdin, buf, len);
 135 }
 136
 137 void HandleClientBoundData(tClient *Client)
 138 {
 139         char    buf[BUFSIZ];
 140          int    len;
 141
 142         len = read(Client->stdout, buf, BUFSIZ);
 143         write(Client->Socket, buf, len);
 144 }
 145