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
  29 #ifndef __CYGWIN32__
  30 #include <netinet/tcp.h>
  31 #endif
  32
  33 #include "signals.h"
  34 #include "gdb_string.h"
  35
  36 struct tcp_ttystate
  37 {
  38   int bogus;
  39 };
  40
  41 static int tcp_open PARAMS ((serial_t scb, const char *name));
  42 static void tcp_raw PARAMS ((serial_t scb));
  43 static int wait_for PARAMS ((serial_t scb, int timeout));
  44 static int tcp_readchar PARAMS ((serial_t scb, int timeout));
  45 static int tcp_setbaudrate PARAMS ((serial_t scb, int rate));
  46 static int tcp_setstopbits PARAMS ((serial_t scb, int num));
  47 static int tcp_write PARAMS ((serial_t scb, const char *str, int len));
  48 /* FIXME: static void tcp_restore PARAMS ((serial_t scb)); */
  49 static void tcp_close PARAMS ((serial_t scb));
  50 static serial_ttystate tcp_get_tty_state PARAMS ((serial_t scb));
  51 static int tcp_set_tty_state PARAMS ((serial_t scb, serial_ttystate state));
  52 static int tcp_return_0 PARAMS ((serial_t));
  53 static int tcp_noflush_set_tty_state PARAMS ((serial_t, serial_ttystate,
  54                                               serial_ttystate));
  55 static void tcp_print_tty_state PARAMS ((serial_t, serial_ttystate));
  56
  57 /* Open up a raw tcp socket */
  58
  59 static int
  60 tcp_open(scb, name)
  61      serial_t scb;
  62      const char *name;
  63 {
  64   char *port_str;
  65   int port;
  66   struct hostent *hostent;
  67   struct sockaddr_in sockaddr;
  68   int tmp;
  69   char hostname[100];
  70   struct protoent *protoent;
  71   int i;
  72
  73   port_str = strchr (name, ':');
  74
  75   if (!port_str)
  76     error ("tcp_open: No colon in host name!"); /* Shouldn't ever happen */
  77
  78   tmp = min (port_str - name, (int) sizeof hostname - 1);
  79   strncpy (hostname, name, tmp); /* Don't want colon */
  80   hostname[tmp] = '\000';       /* Tie off host name */
  81   port = atoi (port_str + 1);
  82
  83   hostent = gethostbyname (hostname);
  84
  85   if (!hostent)
  86     {
  87       fprintf_unfiltered (gdb_stderr, "%s: unknown host\n", hostname);
  88       errno = ENOENT;
  89       return -1;
  90     }
  91
  92   for (i = 1; i <= 15; i++)
  93     {
  94       scb->fd = socket (PF_INET, SOCK_STREAM, 0);
  95       if (scb->fd < 0)
  96         return -1;
  97
  98       /* Allow rapid reuse of this port. */
  99       tmp = 1;
 100       setsockopt (scb->fd, SOL_SOCKET, SO_REUSEADDR, (char *)&tmp, sizeof(tmp));
 101
 102       /* Enable TCP keep alive process. */
 103       tmp = 1;
 104       setsockopt (scb->fd, SOL_SOCKET, SO_KEEPALIVE, (char *)&tmp, sizeof(tmp));
 105
 106       sockaddr.sin_family = PF_INET;
 107       sockaddr.sin_port = htons(port);
 108       memcpy (&sockaddr.sin_addr.s_addr, hostent->h_addr,
 109               sizeof (struct in_addr));
 110
 111       if (!connect (scb->fd, (struct sockaddr *) &sockaddr, sizeof(sockaddr)))
 112         break;
 113
 114       close (scb->fd);
 115       scb->fd = -1;
 116
 117 /* We retry for ECONNREFUSED because that is often a temporary condition, which
 118    happens when the server is being restarted.  */
 119
 120       if (errno != ECONNREFUSED)
 121         return -1;
 122
 123       sleep (1);
 124     }
 125
 126   protoent = getprotobyname ("tcp");
 127   if (!protoent)
 128     return -1;
 129
 130   tmp = 1;
 131   if (setsockopt (scb->fd, protoent->p_proto, TCP_NODELAY,
 132                   (char *)&tmp, sizeof(tmp)))
 133     return -1;
 134
 135   signal(SIGPIPE, SIG_IGN);     /* If we don't do this, then GDB simply exits
 136                                    when the remote side dies.  */
 137
 138   return 0;
 139 }
 140
 141 static serial_ttystate
 142 tcp_get_tty_state(scb)
 143      serial_t scb;
 144 {
 145   struct tcp_ttystate *state;
 146
 147   state = (struct tcp_ttystate *)xmalloc(sizeof *state);
 148
 149   return (serial_ttystate)state;
 150 }
 151
 152 static int
 153 tcp_set_tty_state(scb, ttystate)
 154      serial_t scb;
 155      serial_ttystate ttystate;
 156 {
 157   struct tcp_ttystate *state;
 158
 159   state = (struct tcp_ttystate *)ttystate;
 160
 161   return 0;
 162 }
 163
 164 static int
 165 tcp_return_0 (scb)
 166      serial_t scb;
 167 {
 168   return 0;
 169 }
 170
 171 static void
 172 tcp_raw(scb)
 173      serial_t scb;
 174 {
 175   return;                       /* Always in raw mode */
 176 }
 177
 178 /* Wait for input on scb, with timeout seconds.  Returns 0 on success,
 179    otherwise SERIAL_TIMEOUT or SERIAL_ERROR.
 180
 181    For termio{s}, we actually just setup VTIME if necessary, and let the
 182    timeout occur in the read() in tcp_read().
 183  */
 184
 185 static int
 186 wait_for(scb, timeout)
 187      serial_t scb;
 188      int timeout;
 189 {
 190   int numfds;
 191   struct timeval tv;
 192   fd_set readfds, exceptfds;
 193
 194   FD_ZERO (&readfds);
 195   FD_ZERO (&exceptfds);
 196
 197   tv.tv_sec = timeout;
 198   tv.tv_usec = 0;
 199
 200   FD_SET(scb->fd, &readfds);
 201   FD_SET(scb->fd, &exceptfds);
 202
 203   while (1)
 204     {
 205       if (timeout >= 0)
 206         numfds = select(scb->fd+1, &readfds, 0, &exceptfds, &tv);
 207       else
 208         numfds = select(scb->fd+1, &readfds, 0, &exceptfds, 0);
 209
 210       if (numfds <= 0)
 211         if (numfds == 0)
 212           return SERIAL_TIMEOUT;
 213         else if (errno == EINTR)
 214           continue;
 215         else
 216           return SERIAL_ERROR;  /* Got an error from select or poll */
 217
 218       return 0;
 219     }
 220 }
 221
 222 /* Read a character with user-specified timeout.  TIMEOUT is number of seconds
 223    to wait, or -1 to wait forever.  Use timeout of 0 to effect a poll.  Returns
 224    char if successful.  Returns -2 if timeout expired, EOF if line dropped
 225    dead, or -3 for any other error (see errno in that case). */
 226
 227 static int
 228 tcp_readchar(scb, timeout)
 229      serial_t scb;
 230      int timeout;
 231 {
 232   int status;
 233
 234   if (scb->bufcnt-- > 0)
 235     return *scb->bufp++;
 236
 237   status = wait_for(scb, timeout);
 238
 239   if (status < 0)
 240     return status;
 241
 242   while (1)
 243     {
 244       scb->bufcnt = read(scb->fd, scb->buf, BUFSIZ);
 245       if (scb->bufcnt != -1 || errno != EINTR)
 246         break;
 247     }
 248
 249   if (scb->bufcnt <= 0)
 250     if (scb->bufcnt == 0)
 251       return SERIAL_TIMEOUT;    /* 0 chars means timeout [may need to
 252                                    distinguish between EOF & timeouts
 253                                    someday] */
 254     else
 255       return SERIAL_ERROR;      /* Got an error from read */
 256
 257   scb->bufcnt--;
 258   scb->bufp = scb->buf;
 259   return *scb->bufp++;
 260 }
 261
 262 static int
 263 tcp_noflush_set_tty_state (scb, new_ttystate, old_ttystate)
 264      serial_t scb;
 265      serial_ttystate new_ttystate;
 266      serial_ttystate old_ttystate;
 267 {
 268   return 0;
 269 }
 270
 271 static void
 272 tcp_print_tty_state (scb, ttystate)
 273      serial_t scb;
 274      serial_ttystate ttystate;
 275 {
 276   /* Nothing to print.  */
 277   return;
 278 }
 279
 280 static int
 281 tcp_setbaudrate(scb, rate)
 282      serial_t scb;
 283      int rate;
 284 {
 285   return 0;                     /* Never fails! */
 286 }
 287
 288 static int
 289 tcp_setstopbits(scb, num)
 290      serial_t scb;
 291      int num;
 292 {
 293   return 0;                     /* Never fails! */
 294 }
 295
 296 static int
 297 tcp_write(scb, str, len)
 298      serial_t scb;
 299      const char *str;
 300      int len;
 301 {
 302   int cc;
 303
 304   while (len > 0)
 305     {
 306       cc = write(scb->fd, str, len);
 307
 308       if (cc < 0)
 309         return 1;
 310       len -= cc;
 311       str += cc;
 312     }
 313   return 0;
 314 }
 315
 316 static void
 317 tcp_close(scb)
 318      serial_t scb;
 319 {
 320   if (scb->fd < 0)
 321     return;
 322
 323   close(scb->fd);
 324   scb->fd = -1;
 325 }
 326
 327 static struct serial_ops tcp_ops =
 328 {
 329   "tcp",
 330   0,
 331   tcp_open,
 332   tcp_close,
 333   tcp_readchar,
 334   tcp_write,
 335   tcp_return_0, /* flush output */
 336   tcp_return_0, /* flush input */
 337   tcp_return_0, /* send break */
 338   tcp_raw,
 339   tcp_get_tty_state,
 340   tcp_set_tty_state,
 341   tcp_print_tty_state,
 342   tcp_noflush_set_tty_state,
 343   tcp_setbaudrate,
 344   tcp_setstopbits,
 345 };
 346
 347 void
 348 _initialize_ser_tcp ()
 349 {
 350   serial_add_interface (&tcp_ops);
 351 }