gdb/ser-tcp.c

   1 /* Serial interface for raw TCP connections on Un*x like systems
   2    Copyright 1992, 1993 Free Software Foundation, Inc.
   3
   4 This file is part of GDB.
   5
   6 This program is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2 of the License, or
   9 (at your option) any later version.
  10
  11 This program is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with this program; if not, write to the Free Software
  18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20 #include "defs.h"
  21 #include "serial.h"
  22 #include <sys/types.h>
  23 #include <sys/time.h>
  24 #include <netinet/in.h>
  25 #include <arpa/inet.h>
  26 #include <netdb.h>
  27 #include <sys/socket.h>
  28 #include <netinet/tcp.h>
  29 #include "signals.h"
  30
  31 struct tcp_ttystate
  32 {
  33   int bogus;
  34 };
  35
  36 static int tcp_open PARAMS ((serial_t scb, const char *name));
  37 static void tcp_raw PARAMS ((serial_t scb));
  38 static int wait_for PARAMS ((serial_t scb, int timeout));
  39 static int tcp_readchar PARAMS ((serial_t scb, int timeout));
  40 static int tcp_setbaudrate PARAMS ((serial_t scb, int rate));
  41 static int tcp_write PARAMS ((serial_t scb, const char *str, int len));
  42 static void tcp_restore PARAMS ((serial_t scb));
  43 static void tcp_close PARAMS ((serial_t scb));
  44 static serial_ttystate tcp_get_tty_state PARAMS ((serial_t scb));
  45 static int tcp_set_tty_state PARAMS ((serial_t scb, serial_ttystate state));
  46
  47 /* Open up a raw tcp socket */
  48
  49 static int
  50 tcp_open(scb, name)
  51      serial_t scb;
  52      const char *name;
  53 {
  54   char *port_str;
  55   int port;
  56   struct hostent *hostent;
  57   struct sockaddr_in sockaddr;
  58   int tmp;
  59   char hostname[100];
  60   struct protoent *protoent;
  61
  62   port_str = strchr (name, ':');
  63
  64   if (!port_str)
  65     error ("tcp_open: No colon in host name!"); /* Shouldn't ever happen */
  66
  67   tmp = min (port_str - name, sizeof hostname - 1);
  68   strncpy (hostname, name, tmp); /* Don't want colon */
  69   hostname[tmp] = '\000';       /* Tie off host name */
  70   port = atoi (port_str + 1);
  71
  72   hostent = gethostbyname (hostname);
  73
  74   if (!hostent)
  75     {
  76       fprintf (stderr, "%s: unknown host\n", hostname);
  77       errno = ENOENT;
  78       return -1;
  79     }
  80
  81   scb->fd = socket (PF_INET, SOCK_STREAM, 0);
  82   if (scb->fd < 0)
  83     return -1;
  84
  85   /* Allow rapid reuse of this port. */
  86   tmp = 1;
  87   setsockopt (scb->fd, SOL_SOCKET, SO_REUSEADDR, (char *)&tmp, sizeof(tmp));
  88
  89   /* Enable TCP keep alive process. */
  90   tmp = 1;
  91   setsockopt (scb->fd, SOL_SOCKET, SO_KEEPALIVE, (char *)&tmp, sizeof(tmp));
  92
  93   sockaddr.sin_family = PF_INET;
  94   sockaddr.sin_port = htons(port);
  95   memcpy (&sockaddr.sin_addr.s_addr, hostent->h_addr,
  96           sizeof (struct in_addr));
  97
  98   if (connect (scb->fd, &sockaddr, sizeof(sockaddr)))
  99     {
 100       close(scb->fd);
 101       scb->fd = -1;
 102       return -1;
 103     }
 104
 105   protoent = getprotobyname ("tcp");
 106   if (!protoent)
 107     return -1;
 108
 109   tmp = 1;
 110   if (setsockopt (scb->fd, protoent->p_proto, TCP_NODELAY,
 111                   (char *)&tmp, sizeof(tmp)))
 112     return -1;
 113
 114   signal(SIGPIPE, SIG_IGN);     /* If we don't do this, then GDB simply exits
 115                                    when the remote side dies.  */
 116
 117   return 0;
 118 }
 119
 120 static serial_ttystate
 121 tcp_get_tty_state(scb)
 122      serial_t scb;
 123 {
 124   struct tcp_ttystate *state;
 125
 126   state = (struct tcp_ttystate *)xmalloc(sizeof *state);
 127
 128   return (serial_ttystate)state;
 129 }
 130
 131 static int
 132 tcp_set_tty_state(scb, ttystate)
 133      serial_t scb;
 134      serial_ttystate ttystate;
 135 {
 136   struct tcp_ttystate *state;
 137
 138   state = (struct tcp_ttystate *)ttystate;
 139
 140   return 0;
 141 }
 142
 143 static int
 144 tcp_return_0 (scb)
 145      serial_t scb;
 146 {
 147   return 0;
 148 }
 149
 150 static void
 151 tcp_raw(scb)
 152      serial_t scb;
 153 {
 154   return;                       /* Always in raw mode */
 155 }
 156
 157 /* Wait for input on scb, with timeout seconds.  Returns 0 on success,
 158    otherwise SERIAL_TIMEOUT or SERIAL_ERROR.
 159
 160    For termio{s}, we actually just setup VTIME if necessary, and let the
 161    timeout occur in the read() in tcp_read().
 162  */
 163
 164 static int
 165 wait_for(scb, timeout)
 166      serial_t scb;
 167      int timeout;
 168 {
 169   int numfds;
 170   struct timeval tv;
 171   fd_set readfds, exceptfds;
 172
 173   FD_ZERO (&readfds);
 174   FD_ZERO (&exceptfds);
 175
 176   tv.tv_sec = timeout;
 177   tv.tv_usec = 0;
 178
 179   FD_SET(scb->fd, &readfds);
 180   FD_SET(scb->fd, &exceptfds);
 181
 182   while (1)
 183     {
 184       if (timeout >= 0)
 185         numfds = select(scb->fd+1, &readfds, 0, &exceptfds, &tv);
 186       else
 187         numfds = select(scb->fd+1, &readfds, 0, &exceptfds, 0);
 188
 189       if (numfds <= 0)
 190         if (numfds == 0)
 191           return SERIAL_TIMEOUT;
 192         else if (errno == EINTR)
 193           continue;
 194         else
 195           return SERIAL_ERROR;  /* Got an error from select or poll */
 196
 197       return 0;
 198     }
 199 }
 200
 201 /* Read a character with user-specified timeout.  TIMEOUT is number of seconds
 202    to wait, or -1 to wait forever.  Use timeout of 0 to effect a poll.  Returns
 203    char if successful.  Returns -2 if timeout expired, EOF if line dropped
 204    dead, or -3 for any other error (see errno in that case). */
 205
 206 static int
 207 tcp_readchar(scb, timeout)
 208      serial_t scb;
 209      int timeout;
 210 {
 211   int status;
 212
 213   if (scb->bufcnt-- > 0)
 214     return *scb->bufp++;
 215
 216   status = wait_for(scb, timeout);
 217
 218   if (status < 0)
 219     return status;
 220
 221   scb->bufcnt = read(scb->fd, scb->buf, BUFSIZ);
 222
 223   if (scb->bufcnt <= 0)
 224     if (scb->bufcnt == 0)
 225       return SERIAL_TIMEOUT;    /* 0 chars means timeout [may need to
 226                                    distinguish between EOF & timeouts
 227                                    someday] */
 228     else
 229       return SERIAL_ERROR;      /* Got an error from read */
 230
 231   scb->bufcnt--;
 232   scb->bufp = scb->buf;
 233   return *scb->bufp++;
 234 }
 235
 236 static int
 237 tcp_noflush_set_tty_state (scb, new_ttystate, old_ttystate)
 238      serial_t scb;
 239      serial_ttystate new_ttystate;
 240      serial_ttystate old_ttystate;
 241 {
 242   return 0;
 243 }
 244
 245 static void
 246 tcp_print_tty_state (scb, ttystate)
 247      serial_t scb;
 248      serial_ttystate ttystate;
 249 {
 250   /* Nothing to print.  */
 251   return;
 252 }
 253
 254 static int
 255 tcp_setbaudrate(scb, rate)
 256      serial_t scb;
 257      int rate;
 258 {
 259   return 0;                     /* Never fails! */
 260 }
 261
 262 static int
 263 tcp_set_process_group (scb, ttystate, group)
 264      serial_t scb;
 265      serial_ttystate ttystate;
 266      int group;
 267 {
 268   return 0;
 269 }
 270
 271 static int
 272 tcp_write(scb, str, len)
 273      serial_t scb;
 274      const char *str;
 275      int len;
 276 {
 277   int cc;
 278
 279   while (len > 0)
 280     {
 281       cc = write(scb->fd, str, len);
 282
 283       if (cc < 0)
 284         return 1;
 285       len -= cc;
 286       str += cc;
 287     }
 288   return 0;
 289 }
 290
 291 static void
 292 tcp_close(scb)
 293      serial_t scb;
 294 {
 295   if (scb->fd < 0)
 296     return;
 297
 298   close(scb->fd);
 299   scb->fd = -1;
 300 }
 301
 302 static struct serial_ops tcp_ops =
 303 {
 304   "tcp",
 305   0,
 306   tcp_open,
 307   tcp_close,
 308   tcp_readchar,
 309   tcp_write,
 310   tcp_return_0, /* flush output */
 311   tcp_return_0, /* flush input */
 312   tcp_return_0, /* send break */
 313   tcp_raw,
 314   tcp_get_tty_state,
 315   tcp_set_tty_state,
 316   tcp_print_tty_state,
 317   tcp_noflush_set_tty_state,
 318   tcp_setbaudrate,
 319   tcp_set_process_group
 320 };
 321
 322 void
 323 _initialize_ser_tcp ()
 324 {
 325   serial_add_interface (&tcp_ops);
 326 }