File indexing completed on 2024-04-21 04:03:14

 /**
  * KMuddy scripting - variable support
  *
  * #include this file in a C/C++ script, if you want to use variables
  * in that script.
  *
  * */
 
 /* PUBLIC INTERFACE: */
 
 /** call this at the beginning of your script */
 void initVariableSocket ();
 
 /** call this at the end of your script */
 void closeVariableSocket ();
 
 /** call this to set your script up to listen on an IP port */
 void initIPPort(const int ip_port);
 
 /** wait for and retrieve event notification from IP port */
 void getEvent (char *buffer, int buflen);
 
 /** reads variable value and store it in the buffer (of size buflen+1) */
 void getVariable (const char *name, char *buffer, int buflen);
 
 /** sets a variable value */
 char setVariable (const char *name, const char *value);
 
 /** unsets a variable */
 char unsetVariable (const char *name);
 
 /** increases a variable value */
 char incVariable (const char *name, int delta);
 
 /** decreases a variable value */
 char decVariable (const char *name, int delta);
 
 /** provide a resource */
 char provideResource (const char *name);
 
 /** request a resource */
 char requestResource (const char *name);
 
 /** request variable lock */
 char lockVariable (const char *name);
 
 /** unlock a variable */
 void unlockVariable (const char *name);
 
 /** sends a command to the MUD */
 char sendCommand (const char *command);
 
 
 
 
 /* INTERNAL VARIABLES AND FUNCTIONS -- DO NOT USE IN THE SCRIPT */
 #define MAX_PENDING_CONNECTIONS 5
 char internalBuffer[51];
 int variableSocket = -1;
 int serverSocket   = -1;
 int clientSocket   = -1;
 char simpleCommand (const char *command, const char *name);
 
 void sendAndReceive (const char *sendthis, char *buffer, int buflen);
 
 /* IMPLEMENTATION */
 
 #include <errno.h>
 
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
 #include <sys/socket.h>
 #include <sys/types.h>
 #include <sys/un.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include <kvbox.h>
 
 
 void initVariableSocket ()
 {
    struct sockaddr_un sa;
    char *path;
    path = getenv ("KMUDDY_SOCKET");
    if (!path)
    {
       puts ("Variable KMUDDY_SOCKET is not set - variable support won't work!\n");
       fflush (stdout);
       return; /* bah! */
    }
    variableSocket = socket (PF_UNIX, SOCK_STREAM, 0);
    sa.sun_family = AF_UNIX;
    strcpy (sa.sun_path, path);
    if (connect (variableSocket, (struct sockaddr *) &sa, sizeof (sa)) == -1)
    {
       close (variableSocket);
       variableSocket = -1;  /* :( */
       puts ("Could not connect to KMuddy!\n");
       printf ("Error = %s\n", strerror (errno));
       fflush (stdout);
    }
    /* okay, we should be connected now... */
 }
 
 void closeVariableSocket ()
 {
   if (variableSocket != -1)
      close (variableSocket);
 
   if (serverSocket != -1)
      close (serverSocket);
 
   if (clientSocket != -1)
      close(clientSocket);
 
 }
 
 
 /** call this to set your script up to listen on an IP port */
 void initIPPort(const int ip_port)
 {
    struct sockaddr_in server_address;
    int                val = 1;
    int                result;
 
    serverSocket = socket(AF_INET,
                          SOCK_STREAM,
                          0);
 
    if (serverSocket < 0)
    {
       puts ("Unable to create a socket - server support won't work!\n");
       fflush (stdout);
       return; /* bah! */
    } /* endif unable to obtain a socket */
 
    result = setsockopt(serverSocket,
                        SOL_SOCKET,
                        SO_REUSEADDR,
                        (char *)&val,
                        sizeof(val));
 
    if (result != 0)
    {
       close(serverSocket);
       puts ("Unable to modify socket options - server support won't work!\n");
       fflush (stdout);
       return; /* bah! */
    } /* endif unable to modify socket options */
 
    server_address.sin_family      = AF_INET;
    server_address.sin_addr.s_addr = htonl(INADDR_ANY);
    server_address.sin_port        = htons(ip_port);
 
    result = bind(serverSocket,
                  (struct sockaddr *)&server_address,
                  sizeof(server_address));
 
    if (result != 0)
    {
       close(serverSocket);
       puts ("Unable to bind socket to specified IP port - server support won't work!\n");
       fflush (stdout);
       return; /* bah! */
    } /* endif unable to modify socket options */
 
    result = listen(serverSocket,
                    MAX_PENDING_CONNECTIONS);
 
    if (result != 0)
    {
       close(serverSocket);
       puts ("Unable to listen on specified IP port - server support won't work!\n");
       fflush (stdout);
       return; /* bah! */
    } /* endif unable to modify socket options */
 
 } /* initIPPort */
 
 
 /** wait for and retrieve event notification from IP port */
 void getEvent (char *buffer, int buflen)
 {
    struct sockaddr_in client_address;
 
    int   client_name_size;
    char *dest;
    int   finished = 0;
    int   remaining;
    int   received;
    int   total;
 
    /* Buffer to store incoming TCP/IP data */
    static char recv_buffer[1024];
    const int   recv_buffer_maxsize = 1024;
    static int  recv_amount = 0;  /* Amount actually received from the network */
    static int  recv_offset = 0;  /* Amount processed so far */
    static int  need_skip   = 0;  /* Set if we need to ignore everything until next \n */
 
    int buffer_offset = 0;
 
    buffer[0] = '\0';
 
    if (serverSocket == -1)
    {
       return;
    } /* endif not listening on IP port */
 
    if (clientSocket == -1)
    {
       /* Debug message */
 /*
       puts ("No previous connection from KMuddy - waiting for connection\n");
       fflush (stdout);
 */
 
       client_name_size = sizeof(client_address);
 
       clientSocket = accept(serverSocket,
                             (struct sockaddr *)&client_address,
                             (socklen_t *)&client_name_size);
 
    } // endif no previous dialogue with server
 
    if (clientSocket < 0)
    {
       return;
    } /* endif accept failed */
 
 
    while (!finished)
    {
       if (recv_offset >= recv_amount)
       {
          recv_offset = 0;
 
          recv_amount = recv(clientSocket,
                             recv_buffer,
                             recv_buffer_maxsize,
                             0);
 
       } /* endif need to receive more data from the network */
 
       if (need_skip)
       {
          while ((recv_offset               < recv_amount)&&
                 (recv_buffer[recv_offset] != '\n')         )
          {
             recv_offset++;
          } /* endwhile more characters to skip */
 
          if (recv_offset < recv_amount)
          {
             recv_offset++;
             need_skip = 0;
          } /* endif found \n */
 
       } /* endif need to ignore everything until next \n */
 
       while ((recv_offset               < recv_amount)&&
              (buffer_offset             < buflen-1)   &&
              (recv_buffer[recv_offset] != '\n')         )
       {
          buffer[buffer_offset++] = recv_buffer[recv_offset++];
 
       } /* endwhile not found complete message yet */
 
       if (buffer_offset == buflen-1)
       {
          /* Truncate message */
          buffer[buflen-1] = '\0';
          finished         = 1;
          need_skip        = 1; /* need to ignore everything until next \n */
       } /* endif reached limits of message buffer */
       else if (recv_offset < recv_amount)
       {
          /* Found \n at recv_offset */
          buffer[buffer_offset] = '\0';
          finished = 1;
          recv_offset++;
       } /* endif received full message */
 
    } /* endwhile more work to do to receive complete message */
 
 } /* getEvent */
 
 
 
 void getVariable (const char *name, char *buffer, int buflen)
 {
   int n;
    /* some initial tests */
    if (!name) return;
    if (!buffer) return;
    if (buflen <= 0) return;
    //alocate memory for request-string
    n = strlen (name);
    char *request = (char *) malloc (6 + n);
    //build a request
    strcpy (request, "get ");
    strcat (request, name);
    strcat (request, "\n");
    /* send it and receive the result */
    sendAndReceive (request, buffer, buflen);
    /* free up memory used by the request-string */
    free (request);
 }
 
 char setVariable (const char *name, const char *value)
 {
   int n1, n2;
   /* some initial tests */
   if (!name) return 0;
    if (!value) return 0;
    /* allocate memory for request-string */
    n1 = strlen (name);
    n2 = strlen (value);
    char *request = (char *) malloc (7 + n1 + n2);
    /* build a request */
    strcpy (request, "set ");
    strcat (request, name);
    strcat (request, " ");
    strcat (request, value);
    strcat (request, "\n");
    /* send it and receive the result */
    sendAndReceive (request, internalBuffer, 51);
    /* free up memory used by the request-string */
    free (request);
 
    if (strncmp (internalBuffer, "OK", 2) == 0)
       return 1;  /* success */
    return 0;  /* failure */
 }
 
 char unsetVariable (const char *name)
 {
   return simpleCommand ("unset", name);
 }
 
 char incVariable (const char *name, int delta)
 {
   int n1, n2;
   /* some initial tests */
   if (!name) return 0;
    if (delta <= 0) return 0;
    //alocate memory for request-string
    n1 = strlen (name);
    n2 = 10;
    char *request = (char *) malloc (7 + n1 + n2);
    char *value = (char *) malloc (10);
    sprintf (value, "%d", delta);
    //build a request
    strcpy (request, "inc ");
    strcat (request, name);
    strcat (request, " ");
    strcat (request, value);
    strcat (request, "\n");
    /* send it and receive the result */
    sendAndReceive (request, internalBuffer, 51);
    /* free up memory used by the request-string */
    free (request);
 
    if (strncmp (internalBuffer, "OK", 2) == 0)
       return 1;  /* success */
    return 0;  /* failure */
 }
 
 char decVariable (const char *name, int delta)
 {
   int n1, n2;
   /* some initial tests */
   if (!name) return 0;
    if (delta <= 0) return 0;
    /* allocate memory for request-string */
    n1 = strlen (name);
    n2 = 10;
    char *request = (char *) malloc (7 + n1 + n2);
    char *value = (char *) malloc (10);
    sprintf (value, "%d", delta);
    /* build a request */
    strcpy (request, "dec ");
    strcat (request, name);
    strcat (request, " ");
    strcat (request, value);
    strcat (request, "\n");
    /* send it and receive the result */
    sendAndReceive (request, internalBuffer, 51);
    /* free up memory used by the request-string */
    free (request);
 
    if (strncmp (internalBuffer, "OK", 2) == 0)
       return 1;  /* success */
    return 0;  /* failure */
 }
 
 char provideResource (const char *name)
 {
   return simpleCommand ("provide", name);
 }
 
 char requestResource (const char *name)
 {
   return simpleCommand ("request", name);
 }
 
 char lockVariable (const char *name)
 {
   return simpleCommand ("lock", name);
 }
 
 void unlockVariable (const char *name)
 {
   simpleCommand ("unlock", name);
 }
 
 char simpleCommand (const char *command, const char *name)
 {
   int n,k;
   /* some initial tests */
   if (!name) return 0;
    /* allocate memory for request-string */
    n = strlen (name);
    k = strlen (command);
    char *request = (char *) malloc (3 + k + n);
    /* build a request */
    strcpy (request, command);
    strcat (request, " ");
    strcat (request, name);
    strcat (request, "\n");
    /* send it and receive the result */
    sendAndReceive (request, internalBuffer, 51);
    /* free up memory used by the request-string */
    free (request);
 
    if (strncmp (internalBuffer, "OK", 2) == 0)
       return 1;  /* success */
    return 0;  /* failure */
 }
 
 void sendAndReceive (const char *sendthis, char *buffer, int buflen)
 {
   int n;
    int tobewritten, remaining;
    const char *sendme;
    char myBuf[101];
    char gotNewLine = 0;
    buffer[0] = '\0';
 
    if (variableSocket == -1)
       return;
   tobewritten = strlen (sendthis);
    if (tobewritten == 0)
       return;
    /* pointer to data that hasn't been written yet */
    sendme = sendthis;
    /* write it all */
    while (tobewritten > 0)
    {
       n = write (variableSocket, sendme, strlen (sendme));
       if (n == -1)
          /* TODO: some error reporting */
          return;
       /* shift the pointer */
       tobewritten -= n; // Alex change - moved from above
       sendme += n;
    }
 
    /* read reply from KMuddy */
    remaining = buflen;  /* buffer needs to have one extra byte for \0 */
 
    while (!gotNewLine)
    {
       n = read (variableSocket, myBuf, 100);
 
       if (n == -1) /* bah! */
          return;
       myBuf[n] = '\0';
       if (remaining)
       {
          strncat (buffer, myBuf, remaining);
          remaining -= n;
          if (remaining < 0)
             remaining = 0;
          n = strlen (buffer);
          if (n)
             if (buffer[n - 1] == '\n')
             {
                gotNewLine = 1;
                buffer[n - 1] = '\0';  /* don't return that newline */
             }
       }
    }
 }
 
 
 
 /* ALEX CHANGE */
 char sendCommand (const char *command)
 {
   int n1;
    /* some initial tests */
   if (!command) return 0;
    /* allocate memory for request-string */
    n1 = strlen (command);
    char *request = (char *) malloc (7 + n1);
    /* build a request */
    strcpy (request, "send ");
    strcat (request, command);
    strcat (request, "\n");
    /* send it and receive the result */
    sendAndReceive (request, internalBuffer, 51);
    /* free up memory used by the request-string */
    free (request);
 
    if (strncmp (internalBuffer, "OK", 2) == 0)
       return 1;  /* success */
    return 0;  /* failure */
 }
 
 /* END ALEX CHANGE */