diplodocus.org Git - nmh/blob - docs/historical/mh-6.8.5/uip/ttyw.c

   1 #ifndef BSD42
   2 #undef  TTYD
   3 #endif
   4
   5 #ifdef  TTYD
   6 /* ttyw.c - the writer */
   7
   8 #include <errno.h>
   9 #include <stdio.h>
  10 #include <strings.h>
  11 #include <sys/types.h>
  12 #include <sys/socket.h>
  13 #include <netinet/in.h>
  14 #include <netdb.h>
  15 #ifndef hpux
  16 #include <arpa/inet.h>
  17 #endif
  18 #include "ttyd.h"
  19 #include "ttym.c"
  20
  21 /* \f */
  22
  23 ttyw (command, host, line, user)
  24 char   *command,
  25        *host,
  26        *line,
  27        *user;
  28 {
  29     int     privd,
  30             sd;
  31     unsigned    times;
  32     char        buffer[BUFSIZ];
  33     struct      hostent *hp;
  34     struct      servent *sp;
  35     struct sockaddr_in  tty_socket,
  36                        *tsock = &tty_socket;
  37
  38     if (command == NULL) {
  39         errno = EINVAL;
  40         return NOTOK;
  41     }
  42
  43     if ((sp = getservbyname ("ttyserver", "tcp")) == NULL) {
  44         errno = ENETDOWN;
  45         return NOTOK;
  46     }
  47     if (host == NULL)
  48         (void) gethostname (host = buffer, sizeof buffer);
  49     if ((hp = gethostbyname (host))==NULL) {
  50         errno = ENETDOWN;
  51         return NOTOK;
  52     }
  53
  54     if (line && strncmp (line, "/dev/", strlen ("/dev/")) == 0)
  55         line += strlen ("/dev/");
  56
  57     privd = *command >= 'A' && *command <= 'Z';/* crude */
  58
  59 /* \f */
  60
  61     for (times = 1; times <= 16; times *= 2) {
  62         if ((sd = getport (0, privd)) == NOTOK)
  63             return NOTOK;
  64
  65         bzero ((char *) tsock, sizeof *tsock);
  66         tsock -> sin_family = hp -> h_addrtype;
  67         tsock -> sin_port = sp -> s_port;
  68         bcopy (hp -> h_addr, (char *) &tsock -> sin_addr, hp -> h_length);
  69
  70         if (connect (sd, (struct sockaddr *) tsock, sizeof *tsock) == NOTOK) {
  71             (void) close (sd);
  72             if (errno == ECONNREFUSED || errno == EINTR) {
  73                 sleep (times);
  74                 continue;
  75             }
  76             break;
  77         }
  78
  79         ttym (sd, command, line, user, NULL);
  80         if (ttyv (sd) == NOTOK || ttyv (sd) == NOTOK) {
  81             (void) close (sd);
  82             errno = EPERM;      /* what else??? */
  83             return NOTOK;
  84         }
  85         else
  86             return sd;
  87     }
  88
  89     return NOTOK;
  90 }
  91
  92 /* \f */
  93
  94 static int  getport (options, privd)
  95 unsigned    options;
  96 int     privd;
  97 {
  98     int     sd,
  99             port;
 100     struct sockaddr_in  unx_socket,
 101                        *usock = &unx_socket;
 102
 103     if ((sd = socket (AF_INET, SOCK_STREAM, 0)) == NOTOK)
 104         return sd;
 105
 106     if (options & SO_DEBUG)
 107         (void) setsockopt (sd, SOL_SOCKET, SO_DEBUG, NULL, 0);
 108     (void) setsockopt (sd, SOL_SOCKET, SO_KEEPALIVE, NULL, 0);
 109
 110     if (!privd)
 111         return sd;
 112
 113     usock -> sin_family = AF_INET;
 114     usock -> sin_addr.s_addr = INADDR_ANY;
 115
 116     for (port = IPPORT_RESERVED - 1; port > IPPORT_RESERVED / 2; port--) {
 117         usock -> sin_port = htons (port);
 118
 119         switch (bind (sd, (struct sockaddr *) usock, sizeof *usock)) {
 120             case NOTOK:
 121                 if (errno != EADDRINUSE && errno != EADDRNOTAVAIL)
 122                     return NOTOK;
 123                 continue;
 124
 125             default:
 126                 return sd;
 127         }
 128     }
 129
 130     return NOTOK;
 131 }
 132 #endif  TTYD