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 tcp_open (struct serial *scb, const char *name);
  46 static void tcp_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 tcp_open (struct serial *scb, const char *name)
  59 {
  60   char *port_str, hostname[100];
  61   int n, port, tmp;
  62   struct hostent *hostent;
  63   struct sockaddr_in sockaddr;
  64
  65   port_str = strchr (name, ':');
  66
  67   if (!port_str)
  68     error ("tcp_open: No colon in host name!");    /* Shouldn't ever happen */
  69
  70   tmp = min (port_str - name, (int) sizeof hostname - 1);
  71   strncpy (hostname, name, tmp);        /* Don't want colon */
  72   hostname[tmp] = '\000';       /* Tie off host name */
  73   port = atoi (port_str + 1);
  74
  75   /* default hostname is localhost */
  76   if (!hostname[0])
  77     strcpy (hostname, "localhost");
  78
  79   hostent = gethostbyname (hostname);
  80   if (!hostent)
  81     {
  82       fprintf_unfiltered (gdb_stderr, "%s: unknown host\n", hostname);
  83       errno = ENOENT;
  84       return -1;
  85     }
  86
  87   scb->fd = socket (PF_INET, SOCK_STREAM, 0);
  88   if (scb->fd < 0)
  89     return -1;
  90
  91   sockaddr.sin_family = PF_INET;
  92   sockaddr.sin_port = htons (port);
  93   memcpy (&sockaddr.sin_addr.s_addr, hostent->h_addr,
  94           sizeof (struct in_addr));
  95
  96   /* set socket nonblocking */
  97   tmp = 1;
  98   ioctl (scb->fd, FIONBIO, &tmp);
  99
 100   /* Use Non-blocking connect.  connect() will return 0 if connected already. */
 101   n = connect (scb->fd, (struct sockaddr *) &sockaddr, sizeof (sockaddr));
 102
 103   if (n < 0 && errno != EINPROGRESS)
 104     {
 105       tcp_close (scb);
 106       return -1;
 107     }
 108
 109   if (n)
 110     {
 111       /* looks like we need to wait for the connect */
 112       struct timeval t;
 113       fd_set rset, wset;
 114       int polls = 0;
 115       FD_ZERO (&rset);
 116
 117       do
 118         {
 119           /* While we wait for the connect to complete
 120              poll the UI so it can update or the user can
 121              interrupt. */
 122           if (ui_loop_hook)
 123             {
 124               if (ui_loop_hook (0))
 125                 {
 126                   errno = EINTR;
 127                   tcp_close (scb);
 128                   return -1;
 129                 }
 130             }
 131
 132           FD_SET (scb->fd, &rset);
 133           wset = rset;
 134           t.tv_sec = 0;
 135           t.tv_usec = 1000000 / POLL_INTERVAL;
 136
 137           n = select (scb->fd + 1, &rset, &wset, NULL, &t);
 138           polls++;
 139         }
 140       while (n == 0 && polls <= TIMEOUT * POLL_INTERVAL);
 141       if (n < 0 || polls > TIMEOUT * POLL_INTERVAL)
 142         {
 143           if (polls > TIMEOUT * POLL_INTERVAL)
 144             errno = ETIMEDOUT;
 145           tcp_close (scb);
 146           return -1;
 147         }
 148     }
 149
 150   /* Got something.  Is it an error? */
 151   {
 152     int res, err, len;
 153     len = sizeof(err);
 154     res = getsockopt (scb->fd, SOL_SOCKET, SO_ERROR, &err, &len);
 155     if (res < 0 || err)
 156       {
 157         if (err)
 158           errno = err;
 159         tcp_close (scb);
 160         return -1;
 161       }
 162   }
 163
 164   /* turn off nonblocking */
 165   tmp = 0;
 166   ioctl (scb->fd, FIONBIO, &tmp);
 167
 168   /* Disable Nagle algorithm. Needed in some cases. */
 169   tmp = 1;
 170   setsockopt (scb->fd, IPPROTO_TCP, TCP_NODELAY,
 171               (char *)&tmp, sizeof (tmp));
 172
 173   /* If we don't do this, then GDB simply exits
 174      when the remote side dies.  */
 175   signal (SIGPIPE, SIG_IGN);
 176
 177   return 0;
 178 }
 179
 180 static void
 181 tcp_close (struct serial *scb)
 182 {
 183   if (scb->fd < 0)
 184     return;
 185
 186   close (scb->fd);
 187   scb->fd = -1;
 188 }
 189
 190 void
 191 _initialize_ser_tcp (void)
 192 {
 193   struct serial_ops *ops = XMALLOC (struct serial_ops);
 194   memset (ops, sizeof (struct serial_ops), 0);
 195   ops->name = "tcp";
 196   ops->next = 0;
 197   ops->open = tcp_open;
 198   ops->close = tcp_close;
 199   ops->readchar = ser_unix_readchar;
 200   ops->write = ser_unix_write;
 201   ops->flush_output = ser_unix_nop_flush_output;
 202   ops->flush_input = ser_unix_flush_input;
 203   ops->send_break = ser_unix_nop_send_break;
 204   ops->go_raw = ser_unix_nop_raw;
 205   ops->get_tty_state = ser_unix_nop_get_tty_state;
 206   ops->set_tty_state = ser_unix_nop_set_tty_state;
 207   ops->print_tty_state = ser_unix_nop_print_tty_state;
 208   ops->noflush_set_tty_state = ser_unix_nop_noflush_set_tty_state;
 209   ops->setbaudrate = ser_unix_nop_setbaudrate;
 210   ops->setstopbits = ser_unix_nop_setstopbits;
 211   ops->drain_output = ser_unix_nop_drain_output;
 212   ops->async = ser_unix_async;
 213   serial_add_interface (ops);
 214 }