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
45static int net_open (struct serial *scb, const char *name);
46static void net_close (struct serial *scb);
47extern int (*ui_loop_hook) (int);
48void _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
57static int
58net_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
197static void
198net_close (struct serial *scb)
199{
200  if (scb->fd < 0)
201    return;
202
203  close (scb->fd);
204  scb->fd = -1;
205}
206
207void
208_initialize_ser_tcp (void)
209{
210  struct serial_ops *ops = XMALLOC (struct serial_ops);
211  memset (ops, 0, sizeof (struct serial_ops));
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}
232