sms_serv.c

手机短消息的服务器端和客户端的源代码 是应用于LINUX/UNIX开发环境的

    if ((gsmitem = getnextgsmdev ()) != NULL) {
      if (gsmdevcpy (&gsmdevices[i], gsmitem) == -1)
        syserr ("sms_serv: error copying GSM instance");
      gsmdevices[i].free = TRUE;
      gsmdevices[i].owner = 0;
    }
    else {
      syserr ("sms_serv: error while reading config. file");
    }
  }                                      /* for (i = 0... */
  if (i != ngsmdevs) {
    syslog ((FACILITY | LOG_INFO), "internal error: expected %d, found %d definition(s)",
           ngsmdevs, i);
    syserr ("sms_serv: internal error, not all GSM modules accounted for");
  }
    
  syslog ((FACILITY | LOG_INFO), "found %d GSM module definition(s)", ngsmdevs);

  /*================================Real start of program */
  /* get the hostname I'm running on */
  localhost = (char *) malloc ((MINIBUFF + 1) * sizeof (char));
  if (gethostname (localhost, MINIBUFF) == -1)
    syserr ("sms_serv: can't get host name");

  /* get the port number we should listen to */
  if ((sent = getservbyname ("sms", "tcp")) == NULL)
    syserr ("sms_serv: can't get service port info");
#ifdef INCL_DEBUG_CODE
printf ("found port <%d> for service sms\n", ntohs (sent->s_port));
#endif
    
  /* now fill in the socket address structure */
  s_addr.sin_family = AF_INET;
  s_addr.sin_port = sent->s_port;
  s_addr.sin_addr.s_addr = htonl (INADDR_ANY);
  /* INADDR_ANY allows connection to any valid IP address for this
     host, including the loopback address. */
  
  /* let's create the socket */
  if ((ssfd = socket (AF_INET, SOCK_STREAM, IPPROTO_IP)) == -1)
    syserr ("sms_serv: can't create socket");
  
  /* set socket options (INA)*/
  optval = 1;
  if (setsockopt (ssfd, SOL_SOCKET, SO_REUSEADDR, &optval, sizeof (optval))) {
       syserr ("sms_serv: can't set socket options to reuse");
  }

  /* load access control list */
  acl_list_init (&gsm_acl);
  if (! read_acl (&gsm_acl)) {
    syserr ("sms_serv: can't read access control list");
  }
  /* end INA */

  /* now bind the socket to the server address */
  if (bind (ssfd, (struct sockaddr *) &s_addr, sizeof (s_addr)) == -1)
    syserr ("sms_serv: can't bind socket");
    
  /* create the client queue on the socket */
  if (listen (ssfd, MAXCLIENTCONN) == -1)
    syserr ("sms_serv: can't listen to that many connections");

  /* set the flags to make the socket "non-blocking" */
  if ((sockflags = fcntl (ssfd, F_GETFL, 0)) == -1)
    syserr ("sms_serv: can't get socket descriptor attributes");
  if (fcntl (ssfd, F_SETFL, (O_NONBLOCK | sockflags)) == -1)
    syserr ("sms_serv: can't set socket descriptor attributes");

  /* initialize "last checked" time */
  lastchked = time (NULL);
  starttime = lastchked;
  
  syslog ((FACILITY | LOG_INFO), "server now ready to answer requests.");
  /*---------------------------Start real processing loop */
  while (TRUE) {
    /* wait for a client to connect */
    if ((csfd = accept (ssfd, (struct sockaddr *) &c_addr, &c_addr_len)) == -1) {
      /* no connection - check the reason of the "error" */
      switch (errno) {
        case EWOULDBLOCK:
	  /* no error - time to check the mailbox ? */
	  if (difftime (time (NULL), lastchked) >= MBCHKINTERVAL) {
	    syslog ((FACILITY | LOG_INFO), "initiating mailbox check.");

	    /* now fork a child to handle mailbox check */
	    pid = fork ();
	    switch (pid) {
	      case (-1):                         /* error */
		syserr ("sms_serv: can't fork");
	        break;

	      case (0):
	        /* ###########< I'm the child >########## */
	        /*----Initialize child-specific variables */
		/*------------------------------Now do it */
		mbcheck_wrapper ();
		/*----------------------------Child exits */
		exit (0);
	        break;           /* Just to be consistent */

	      default:
	        /* ##########< I'm the father >########## */
		/* re-initialize timer */
	        lastchked = time (NULL);
	        break;

	    }                             /* switch (pid) */
	  }                            /* if (difftime... */
	  break;

	default:
	  /* there was a "real" error */
          syserr ("sms_serv: can't accept incoming connection");
	  break;
      }                                 /* switch (errno) */
    }
    else { /* we have a connection - handle it */
      /* first check it against the acl (INA) */
      if (! check_acl (&c_addr.sin_addr, gsm_acl)) {
        syslog ((FACILITY | LOG_WARNING), "illegal connect from [%s]", inet_ntoa (c_addr.sin_addr));
        /* close the socket */
        if (close (csfd) == -1)
          syserr ("sms_serv: can't close client socket");
        continue;
      }

      /* for logging purposes */
      syslog ((FACILITY | LOG_NOTICE), "connect from [%s]", inet_ntoa (c_addr.sin_addr));
    
      /* Now fork a child to handle each individ. request & go on listening */
      pid = fork ();
      switch (pid) {
        case (-1):                               /* error */
          syserr ("sms_serv: can't fork");
	  break;
	
        case (0):
	  /* ###############< I'm the child >############ */
	  /*----------Initialize child-specific variables */
	  /* allocate space for the symbols */
	  symbols.smsc = (char *) malloc ((MAXPHNUMLEN + 1) * sizeof (char));
	  symbols.destgsm = (char *) malloc ((MAXPHNUMLEN + 1) * sizeof (char));
	  symbols.message = (char *) malloc ((MAXMSGLEN + 1) * sizeof (char));
	  symbols.user = (char *) malloc ((MAXUIDLEN + 1) * sizeof (char));

	  /* set those symbols to their default values */
	  strcpy (symbols.smsc, DEFAULTSMSC);
	  symbols.destgsm[0] = '\0';
	  symbols.message[0] = '\0';
	  symbols.user[0] = '\0';

	  /* scratch space for communication with the client */
	  buffer = (char *) malloc ((BUFFSIZE + 1) * sizeof (char));
	  buffer[0] = '\0';  

	  /*------------------------------Server announce */
	  sprintf (buffer, "SMS-Link for Linux, ver %s (%s) on %s\r\n", SMS_SERV_VERSION,
          	 SMS_SERV_DATE, localhost);
	  tellsock (csfd, buffer);
	  sprintf (buffer, "(c) Les Ateliers du Heron, 1998 for Scitex Europe, S.A.\r\n"
	          "(c) Internet Access AG, 1999\r\n\r\n");
	  tellsock (csfd, buffer);

	  /* enter the parser module - handle dialogue with client */
	  while (1) {
            /* display prompt */
            sprintf (buffer, PROMPT);
            tellsock (csfd, buffer);
	    /* get client data */
	    buffer[0] = '\0';
	    nread = read (csfd, buffer, BUFFSIZE);
	    if (nread == -1)
	      syserr ("sms_serv: error while reading from socket");
	    buffer[nread] = '\0';     /* may not be needed, but can't harm */
            /* prepare variables to be used by flex in the new YYINPUT */
	    myinputptr = buffer;
	    myinputlim = buffer + strlen (buffer);
	    /* parse client data */
	    parser ();
	  }                                  /* while (1) */

	  /*--------------------------Close client socket */
	  if (close (csfd) == -1)
	    syserr ("sms_serv: can't close client socket");

	  /*---------------------------------Child exists */
	  exit (0);
	  break; /* just to be consistent */
      
        default:
  	  /* #############< I'm the father >############# */
	  /*--------------------------Close client socket */
	  if (close (csfd) == -1)
	    syserr ("sms_serv: can't close client socket");
	  break;
	
      }                                   /* switch (pid) */
    }                           /* if accept() .. else .. */
    /* give the CPU some rest */
    sleep (1);
  }                                          /* while (1) */
  /*------------------------------------------Conclusions */
  /* close server socket */
  if (close (ssfd) == -1)
    syserr ("sms_serv: can't close server socket");
    
  /* let's clean what's allocated on the heap */
  free (buffer);
  free (destgsm);
  free (message);
  free (localhost);
  /*------------------------------------------End program */
  exit (0);
}                                              /* main () */

/*==========================================================
 * EOF : sms_serv.c
 *===================*/