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