gdb/ser-tcp.c

   1 /* Serial interface for raw TCP connections on Un*x like systems
   2    Copyright 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2001
   3    Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #include "defs.h"
  23 #include "serial.h"
  24 #include "ser-unix.h"
  25
  26 #include <sys/types.h>
  27
  28 #ifdef HAVE_SYS_FILIO_H
  29 #include <sys/filio.h>  /* For FIONBIO. */
  30 #endif
  31 #ifdef HAVE_SYS_IOCTL_H
  32 #include <sys/ioctl.h>  /* For FIONBIO. */
  33 #endif
  34
  35 #include <sys/time.h>
  36 #include <netinet/in.h>
  37 #include <arpa/inet.h>
  38 #include <netdb.h>
  39 #include <sys/socket.h>
  40 #include <netinet/tcp.h>
  41
  42 #include <signal.h>
  43 #include "gdb_string.h"
  44
  45 static int net_open (struct serial *scb, const char *name);
  46 static void net_close (struct serial *scb);
  47 extern int (*ui_loop_hook) (int);
  48 void _initialize_ser_tcp (void);
  49
  50 /* seconds to wait for connect */
  51 #define TIMEOUT 15
  52 /* how many times per second to poll ui_loop_hook */
  53 #define POLL_INTERVAL 2
  54
  55 /* Open a tcp socket */
  56
  57 static int
  58 net_open (struct serial *scb, const char *name)
  59 {
  60   char *port_str, hostname[100];
  61   int n, port, tmp;
  62   int use_udp;
  63   struct hostent *hostent;
  64   struct sockaddr_in sockaddr;
  65
  66   use_udp = 0;
  67   if (strncmp (name, "udp:", 4) == 0)
  68     {
  69       use_udp = 1;
  70       name = name + 4;
  71     }
  72   else if (strncmp (name, "tcp:", 4) == 0)
  73     name = name + 4;
  74
  75   port_str = strchr (name, ':');
  76
  77   if (!port_str)
  78     error ("net_open: No colon in host name!");    /* Shouldn't ever happen */
  79
  80   tmp = min (port_str - name, (int) sizeof hostname - 1);
  81   strncpy (hostname, name, tmp);        /* Don't want colon */
  82   hostname[tmp] = '\000';       /* Tie off host name */
  83   port = atoi (port_str + 1);
  84
  85   /* default hostname is localhost */
  86   if (!hostname[0])
  87     strcpy (hostname, "localhost");
  88
  89   hostent = gethostbyname (hostname);
  90   if (!hostent)
  91     {
  92       fprintf_unfiltered (gdb_stderr, "%s: unknown host\n", hostname);
  93       errno = ENOENT;
  94       return -1;
  95     }
  96
  97   if (use_udp)
  98     scb->fd = socket (PF_INET, SOCK_DGRAM, 0);
  99   else
 100     scb->fd = socket (PF_INET, SOCK_STREAM, 0);
 101
 102   if (scb->fd < 0)
 103     return -1;
 104
 105   sockaddr.sin_family = PF_INET;
 106   sockaddr.sin_port = htons (port);
 107   memcpy (&sockaddr.sin_addr.s_addr, hostent->h_addr,
 108           sizeof (struct in_addr));
 109
 110   /* set socket nonblocking */
 111   tmp = 1;
 112   ioctl (scb->fd, FIONBIO, &tmp);
 113
 114   /* Use Non-blocking connect.  connect() will return 0 if connected already. */
 115   n = connect (scb->fd, (struct sockaddr *) &sockaddr, sizeof (sockaddr));
 116
 117   if (n < 0 && errno != EINPROGRESS)
 118     {
 119       net_close (scb);
 120       return -1;
 121     }
 122
 123   if (n)
 124     {
 125       /* looks like we need to wait for the connect */
 126       struct timeval t;
 127       fd_set rset, wset;
 128       int polls = 0;
 129       FD_ZERO (&rset);
 130
 131       do
 132         {
 133           /* While we wait for the connect to complete
 134              poll the UI so it can update or the user can
 135              interrupt. */
 136           if (ui_loop_hook)
 137             {
 138               if (ui_loop_hook (0))
 139                 {
 140                   errno = EINTR;
 141                   net_close (scb);
 142                   return -1;
 143                 }
 144             }
 145
 146           FD_SET (scb->fd, &rset);
 147           wset = rset;
 148           t.tv_sec = 0;
 149           t.tv_usec = 1000000 / POLL_INTERVAL;
 150
 151           n = select (scb->fd + 1, &rset, &wset, NULL, &t);
 152           polls++;
 153         }
 154       while (n == 0 && polls <= TIMEOUT * POLL_INTERVAL);
 155       if (n < 0 || polls > TIMEOUT * POLL_INTERVAL)
 156         {
 157           if (polls > TIMEOUT * POLL_INTERVAL)
 158             errno = ETIMEDOUT;
 159           net_close (scb);
 160           return -1;
 161         }
 162     }
 163
 164   /* Got something.  Is it an error? */
 165   {
 166     int res, err, len;
 167     len = sizeof(err);
 168     res = getsockopt (scb->fd, SOL_SOCKET, SO_ERROR, &err, &len);
 169     if (res < 0 || err)
 170       {
 171         if (err)
 172           errno = err;
 173         net_close (scb);
 174         return -1;
 175       }
 176   }
 177
 178   /* turn off nonblocking */
 179   tmp = 0;
 180   ioctl (scb->fd, FIONBIO, &tmp);
 181
 182   if (use_udp == 0)
 183     {
 184       /* Disable Nagle algorithm. Needed in some cases. */
 185       tmp = 1;
 186       setsockopt (scb->fd, IPPROTO_TCP, TCP_NODELAY,
 187                   (char *)&tmp, sizeof (tmp));
 188     }
 189
 190   /* If we don't do this, then GDB simply exits
 191      when the remote side dies.  */
 192   signal (SIGPIPE, SIG_IGN);
 193
 194   return 0;
 195 }
 196
 197 static void
 198 net_close (struct serial *scb)
 199 {
 200   if (scb->fd < 0)
 201     return;
 202
 203   close (scb->fd);
 204   scb->fd = -1;
 205 }
 206
 207 void
 208 _initialize_ser_tcp (void)
 209 {
 210   struct serial_ops *ops = XMALLOC (struct serial_ops);
 211   memset (ops, sizeof (struct serial_ops), 0);
 212   ops->name = "tcp";
 213   ops->next = 0;
 214   ops->open = net_open;
 215   ops->close = net_close;
 216   ops->readchar = ser_unix_readchar;
 217   ops->write = ser_unix_write;
 218   ops->flush_output = ser_unix_nop_flush_output;
 219   ops->flush_input = ser_unix_flush_input;
 220   ops->send_break = ser_unix_nop_send_break;
 221   ops->go_raw = ser_unix_nop_raw;
 222   ops->get_tty_state = ser_unix_nop_get_tty_state;
 223   ops->set_tty_state = ser_unix_nop_set_tty_state;
 224   ops->print_tty_state = ser_unix_nop_print_tty_state;
 225   ops->noflush_set_tty_state = ser_unix_nop_noflush_set_tty_state;
 226   ops->setbaudrate = ser_unix_nop_setbaudrate;
 227   ops->setstopbits = ser_unix_nop_setstopbits;
 228   ops->drain_output = ser_unix_nop_drain_output;
 229   ops->async = ser_unix_async;
 230   serial_add_interface (ops);
 231 }