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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, 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 #include "gdb_string.h"
  31
  32 struct tcp_ttystate
  33 {
  34   int bogus;
  35 };
  36
  37 static int tcp_open PARAMS ((serial_t scb, const char *name));
  38 static void tcp_raw PARAMS ((serial_t scb));
  39 static int wait_for PARAMS ((serial_t scb, int timeout));
  40 static int tcp_readchar PARAMS ((serial_t scb, int timeout));
  41 static int tcp_setbaudrate PARAMS ((serial_t scb, int rate));
  42 static int tcp_setstopbits PARAMS ((serial_t scb, int num));
  43 static int tcp_write PARAMS ((serial_t scb, const char *str, int len));
  44 /* FIXME: static void tcp_restore PARAMS ((serial_t scb)); */
  45 static void tcp_close PARAMS ((serial_t scb));
  46 static serial_ttystate tcp_get_tty_state PARAMS ((serial_t scb));
  47 static int tcp_set_tty_state PARAMS ((serial_t scb, serial_ttystate state));
  48 static int tcp_return_0 PARAMS ((serial_t));
  49 static int tcp_noflush_set_tty_state PARAMS ((serial_t, serial_ttystate,
  50                                               serial_ttystate));
  51 static void tcp_print_tty_state PARAMS ((serial_t, serial_ttystate));
  52
  53 /* Open up a raw tcp socket */
  54
  55 static int
  56 tcp_open(scb, name)
  57      serial_t scb;
  58      const char *name;
  59 {
  60   char *port_str;
  61   int port;
  62   struct hostent *hostent;
  63   struct sockaddr_in sockaddr;
  64   int tmp;
  65   char hostname[100];
  66   struct protoent *protoent;
  67   int i;
  68
  69   port_str = strchr (name, ':');
  70
  71   if (!port_str)
  72     error ("tcp_open: No colon in host name!"); /* Shouldn't ever happen */
  73
  74   tmp = min (port_str - name, (int) sizeof hostname - 1);
  75   strncpy (hostname, name, tmp); /* Don't want colon */
  76   hostname[tmp] = '\000';       /* Tie off host name */
  77   port = atoi (port_str + 1);
  78
  79   hostent = gethostbyname (hostname);
  80
  81   if (!hostent)
  82     {
  83       fprintf_unfiltered (gdb_stderr, "%s: unknown host\n", hostname);
  84       errno = ENOENT;
  85       return -1;
  86     }
  87
  88   for (i = 1; i <= 15; i++)
  89     {
  90       scb->fd = socket (PF_INET, SOCK_STREAM, 0);
  91       if (scb->fd < 0)
  92         return -1;
  93
  94       /* Allow rapid reuse of this port. */
  95       tmp = 1;
  96       setsockopt (scb->fd, SOL_SOCKET, SO_REUSEADDR, (char *)&tmp, sizeof(tmp));
  97
  98       /* Enable TCP keep alive process. */
  99       tmp = 1;
 100       setsockopt (scb->fd, SOL_SOCKET, SO_KEEPALIVE, (char *)&tmp, sizeof(tmp));
 101
 102       sockaddr.sin_family = PF_INET;
 103       sockaddr.sin_port = htons(port);
 104       memcpy (&sockaddr.sin_addr.s_addr, hostent->h_addr,
 105               sizeof (struct in_addr));
 106
 107       if (!connect (scb->fd, (struct sockaddr *) &sockaddr, sizeof(sockaddr)))
 108         break;
 109
 110       close (scb->fd);
 111       scb->fd = -1;
 112
 113 /* We retry for ECONNREFUSED because that is often a temporary condition, which
 114    happens when the server is being restarted.  */
 115
 116       if (errno != ECONNREFUSED)
 117         return -1;
 118
 119       sleep (1);
 120     }
 121
 122   protoent = getprotobyname ("tcp");
 123   if (!protoent)
 124     return -1;
 125
 126   tmp = 1;
 127   if (setsockopt (scb->fd, protoent->p_proto, TCP_NODELAY,
 128                   (char *)&tmp, sizeof(tmp)))
 129     return -1;
 130
 131   signal(SIGPIPE, SIG_IGN);     /* If we don't do this, then GDB simply exits
 132                                    when the remote side dies.  */
 133
 134   return 0;
 135 }
 136
 137 static serial_ttystate
 138 tcp_get_tty_state(scb)
 139      serial_t scb;
 140 {
 141   struct tcp_ttystate *state;
 142
 143   state = (struct tcp_ttystate *)xmalloc(sizeof *state);
 144
 145   return (serial_ttystate)state;
 146 }
 147
 148 static int
 149 tcp_set_tty_state(scb, ttystate)
 150      serial_t scb;
 151      serial_ttystate ttystate;
 152 {
 153   struct tcp_ttystate *state;
 154
 155   state = (struct tcp_ttystate *)ttystate;
 156
 157   return 0;
 158 }
 159
 160 static int
 161 tcp_return_0 (scb)
 162      serial_t scb;
 163 {
 164   return 0;
 165 }
 166
 167 static void
 168 tcp_raw(scb)
 169      serial_t scb;
 170 {
 171   return;                       /* Always in raw mode */
 172 }
 173
 174 /* Wait for input on scb, with timeout seconds.  Returns 0 on success,
 175    otherwise SERIAL_TIMEOUT or SERIAL_ERROR.
 176
 177    For termio{s}, we actually just setup VTIME if necessary, and let the
 178    timeout occur in the read() in tcp_read().
 179  */
 180
 181 static int
 182 wait_for(scb, timeout)
 183      serial_t scb;
 184      int timeout;
 185 {
 186   int numfds;
 187   struct timeval tv;
 188   fd_set readfds, exceptfds;
 189
 190   FD_ZERO (&readfds);
 191   FD_ZERO (&exceptfds);
 192
 193   tv.tv_sec = timeout;
 194   tv.tv_usec = 0;
 195
 196   FD_SET(scb->fd, &readfds);
 197   FD_SET(scb->fd, &exceptfds);
 198
 199   while (1)
 200     {
 201       if (timeout >= 0)
 202         numfds = select(scb->fd+1, &readfds, 0, &exceptfds, &tv);
 203       else
 204         numfds = select(scb->fd+1, &readfds, 0, &exceptfds, 0);
 205
 206       if (numfds <= 0)
 207         if (numfds == 0)
 208           return SERIAL_TIMEOUT;
 209         else if (errno == EINTR)
 210           continue;
 211         else
 212           return SERIAL_ERROR;  /* Got an error from select or poll */
 213
 214       return 0;
 215     }
 216 }
 217
 218 /* Read a character with user-specified timeout.  TIMEOUT is number of seconds
 219    to wait, or -1 to wait forever.  Use timeout of 0 to effect a poll.  Returns
 220    char if successful.  Returns -2 if timeout expired, EOF if line dropped
 221    dead, or -3 for any other error (see errno in that case). */
 222
 223 static int
 224 tcp_readchar(scb, timeout)
 225      serial_t scb;
 226      int timeout;
 227 {
 228   int status;
 229
 230   if (scb->bufcnt-- > 0)
 231     return *scb->bufp++;
 232
 233   status = wait_for(scb, timeout);
 234
 235   if (status < 0)
 236     return status;
 237
 238   while (1)
 239     {
 240       scb->bufcnt = read(scb->fd, scb->buf, BUFSIZ);
 241       if (scb->bufcnt != -1 || errno != EINTR)
 242         break;
 243     }
 244
 245   if (scb->bufcnt <= 0)
 246     if (scb->bufcnt == 0)
 247       return SERIAL_TIMEOUT;    /* 0 chars means timeout [may need to
 248                                    distinguish between EOF & timeouts
 249                                    someday] */
 250     else
 251       return SERIAL_ERROR;      /* Got an error from read */
 252
 253   scb->bufcnt--;
 254   scb->bufp = scb->buf;
 255   return *scb->bufp++;
 256 }
 257
 258 static int
 259 tcp_noflush_set_tty_state (scb, new_ttystate, old_ttystate)
 260      serial_t scb;
 261      serial_ttystate new_ttystate;
 262      serial_ttystate old_ttystate;
 263 {
 264   return 0;
 265 }
 266
 267 static void
 268 tcp_print_tty_state (scb, ttystate)
 269      serial_t scb;
 270      serial_ttystate ttystate;
 271 {
 272   /* Nothing to print.  */
 273   return;
 274 }
 275
 276 static int
 277 tcp_setbaudrate(scb, rate)
 278      serial_t scb;
 279      int rate;
 280 {
 281   return 0;                     /* Never fails! */
 282 }
 283
 284 static int
 285 tcp_setstopbits(scb, num)
 286      serial_t scb;
 287      int num;
 288 {
 289   return 0;                     /* Never fails! */
 290 }
 291
 292 static int
 293 tcp_write(scb, str, len)
 294      serial_t scb;
 295      const char *str;
 296      int len;
 297 {
 298   int cc;
 299
 300   while (len > 0)
 301     {
 302       cc = write(scb->fd, str, len);
 303
 304       if (cc < 0)
 305         return 1;
 306       len -= cc;
 307       str += cc;
 308     }
 309   return 0;
 310 }
 311
 312 static void
 313 tcp_close(scb)
 314      serial_t scb;
 315 {
 316   if (scb->fd < 0)
 317     return;
 318
 319   close(scb->fd);
 320   scb->fd = -1;
 321 }
 322
 323 static struct serial_ops tcp_ops =
 324 {
 325   "tcp",
 326   0,
 327   tcp_open,
 328   tcp_close,
 329   tcp_readchar,
 330   tcp_write,
 331   tcp_return_0, /* flush output */
 332   tcp_return_0, /* flush input */
 333   tcp_return_0, /* send break */
 334   tcp_raw,
 335   tcp_get_tty_state,
 336   tcp_set_tty_state,
 337   tcp_print_tty_state,
 338   tcp_noflush_set_tty_state,
 339   tcp_setbaudrate,
 340   tcp_setstopbits,
 341 };
 342
 343 void
 344 _initialize_ser_tcp ()
 345 {
 346   serial_add_interface (&tcp_ops);
 347 }