1 /* Serial interface for raw TCP connections on Un*x like systems.
3 Copyright (C) 1992-2017 Free Software Foundation, Inc.
5 This file is part of GDB.
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 3 of the License, or
10 (at your option) any later version.
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.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
25 #include "cli/cli-decode.h"
26 #include "cli/cli-setshow.h"
27 #include "filestuff.h"
29 #include <sys/types.h>
31 #ifdef HAVE_SYS_FILIO_H
32 #include <sys/filio.h> /* For FIONBIO. */
34 #ifdef HAVE_SYS_IOCTL_H
35 #include <sys/ioctl.h> /* For FIONBIO. */
38 #include "gdb_sys_time.h"
43 #define ETIMEDOUT WSAETIMEDOUT
45 #define close(fd) closesocket (fd)
46 #define ioctl ioctlsocket
48 #include <netinet/in.h>
49 #include <arpa/inet.h>
51 #include <sys/socket.h>
52 #include <netinet/tcp.h>
56 #include "gdb_select.h"
59 #ifndef HAVE_SOCKLEN_T
60 typedef int socklen_t
;
63 /* For "set tcp" and "show tcp". */
65 static struct cmd_list_element
*tcp_set_cmdlist
;
66 static struct cmd_list_element
*tcp_show_cmdlist
;
68 /* Whether to auto-retry refused connections. */
70 static int tcp_auto_retry
= 1;
72 /* Timeout period for connections, in seconds. */
74 static unsigned int tcp_retry_limit
= 15;
76 /* How many times per second to poll deprecated_ui_loop_hook. */
78 #define POLL_INTERVAL 5
80 /* Helper function to wait a while. If SCB is non-null, wait on its
81 file descriptor. Otherwise just wait on a timeout, updating *POLLS.
82 Returns -1 on timeout or interrupt, otherwise the value of select. */
85 wait_for_connect (struct serial
*scb
, unsigned int *polls
)
90 /* While we wait for the connect to complete,
91 poll the UI so it can update or the user can
93 if (deprecated_ui_loop_hook
&& deprecated_ui_loop_hook (0))
99 /* Check for timeout. */
100 if (*polls
> tcp_retry_limit
* POLL_INTERVAL
)
106 /* Back off to polling once per second after the first POLL_INTERVAL
108 if (*polls
< POLL_INTERVAL
)
111 t
.tv_usec
= 1000000 / POLL_INTERVAL
;
121 fd_set rset
, wset
, eset
;
124 FD_SET (scb
->fd
, &rset
);
128 /* POSIX systems return connection success or failure by signalling
129 wset. Windows systems return success in wset and failure in
132 We must call select here, rather than gdb_select, because
133 the serial structure has not yet been initialized - the
134 MinGW select wrapper will not know that this FD refers
136 n
= select (scb
->fd
+ 1, &rset
, &wset
, &eset
, &t
);
139 /* Use gdb_select here, since we have no file descriptors, and on
140 Windows, plain select doesn't work in that case. */
141 n
= gdb_select (0, NULL
, NULL
, NULL
, &t
);
143 /* If we didn't time out, only count it as one poll. */
144 if (n
> 0 || *polls
< POLL_INTERVAL
)
147 (*polls
) += POLL_INTERVAL
;
152 /* Open a tcp socket. */
155 net_open (struct serial
*scb
, const char *name
)
158 const char *port_str
;
161 struct hostent
*hostent
;
162 struct sockaddr_in sockaddr
;
168 unsigned int polls
= 0;
171 if (startswith (name
, "udp:"))
176 else if (startswith (name
, "tcp:"))
179 port_str
= strchr (name
, ':');
182 error (_("net_open: No colon in host name!")); /* Shouldn't ever
185 tmp
= std::min (port_str
- name
, (ptrdiff_t) sizeof hostname
- 1);
186 strncpy (hostname
, name
, tmp
); /* Don't want colon. */
187 hostname
[tmp
] = '\000'; /* Tie off host name. */
188 port
= atoi (port_str
+ 1);
190 /* Default hostname is localhost. */
192 strcpy (hostname
, "localhost");
194 hostent
= gethostbyname (hostname
);
197 fprintf_unfiltered (gdb_stderr
, "%s: unknown host\n", hostname
);
202 sockaddr
.sin_family
= PF_INET
;
203 sockaddr
.sin_port
= htons (port
);
204 memcpy (&sockaddr
.sin_addr
.s_addr
, hostent
->h_addr
,
205 sizeof (struct in_addr
));
210 scb
->fd
= gdb_socket_cloexec (PF_INET
, SOCK_DGRAM
, 0);
212 scb
->fd
= gdb_socket_cloexec (PF_INET
, SOCK_STREAM
, 0);
217 /* Set socket nonblocking. */
219 ioctl (scb
->fd
, FIONBIO
, &ioarg
);
221 /* Use Non-blocking connect. connect() will return 0 if connected
223 n
= connect (scb
->fd
, (struct sockaddr
*) &sockaddr
, sizeof (sockaddr
));
228 int err
= WSAGetLastError();
233 /* Maybe we're waiting for the remote target to become ready to
234 accept connections. */
237 && err
== WSAECONNREFUSED
239 && err
== ECONNREFUSED
241 && wait_for_connect (NULL
, &polls
) >= 0)
249 /* Under Windows, calling "connect" with a non-blocking socket
250 results in WSAEWOULDBLOCK, not WSAEINPROGRESS. */
251 err
!= WSAEWOULDBLOCK
262 /* Looks like we need to wait for the connect. */
265 n
= wait_for_connect (scb
, &polls
);
275 /* Got something. Is it an error? */
281 /* On Windows, the fourth parameter to getsockopt is a "char *";
282 on UNIX systems it is generally "void *". The cast to "char *"
283 is OK everywhere, since in C++ any data pointer type can be
284 implicitly converted to "void *". */
285 res
= getsockopt (scb
->fd
, SOL_SOCKET
, SO_ERROR
, (char *) &err
, &len
);
288 /* Maybe the target still isn't ready to accept the connection. */
291 && err
== WSAECONNREFUSED
293 && err
== ECONNREFUSED
295 && wait_for_connect (NULL
, &polls
) >= 0)
307 /* Turn off nonblocking. */
309 ioctl (scb
->fd
, FIONBIO
, &ioarg
);
313 /* Disable Nagle algorithm. Needed in some cases. */
315 setsockopt (scb
->fd
, IPPROTO_TCP
, TCP_NODELAY
,
316 (char *)&tmp
, sizeof (tmp
));
320 /* If we don't do this, then GDB simply exits
321 when the remote side dies. */
322 signal (SIGPIPE
, SIG_IGN
);
329 net_close (struct serial
*scb
)
339 net_read_prim (struct serial
*scb
, size_t count
)
341 /* Need to cast to silence -Wpointer-sign on MinGW, as Winsock's
342 'recv' takes 'char *' as second argument, while 'scb->buf' is
343 'unsigned char *'. */
344 return recv (scb
->fd
, (char *) scb
->buf
, count
, 0);
348 net_write_prim (struct serial
*scb
, const void *buf
, size_t count
)
350 /* On Windows, the second parameter to send is a "const char *"; on
351 UNIX systems it is generally "const void *". The cast to "const
352 char *" is OK everywhere, since in C++ any data pointer type can
353 be implicitly converted to "const void *". */
354 return send (scb
->fd
, (const char *) buf
, count
, 0);
358 ser_tcp_send_break (struct serial
*scb
)
360 /* Send telnet IAC and BREAK characters. */
361 return (serial_write (scb
, "\377\363", 2));
364 /* Support for "set tcp" and "show tcp" commands. */
367 set_tcp_cmd (char *args
, int from_tty
)
369 help_list (tcp_set_cmdlist
, "set tcp ", all_commands
, gdb_stdout
);
373 show_tcp_cmd (char *args
, int from_tty
)
375 help_list (tcp_show_cmdlist
, "show tcp ", all_commands
, gdb_stdout
);
382 static const struct serial_ops tcp_ops
=
390 ser_base_flush_output
,
391 ser_base_flush_input
,
394 ser_base_get_tty_state
,
395 ser_base_copy_tty_state
,
396 ser_base_set_tty_state
,
397 ser_base_print_tty_state
,
398 ser_base_noflush_set_tty_state
,
399 ser_base_setbaudrate
,
400 ser_base_setstopbits
,
402 ser_base_drain_output
,
408 #endif /* USE_WIN32API */
411 _initialize_ser_tcp (void)
414 /* Do nothing; the TCP serial operations will be initialized in
417 serial_add_interface (&tcp_ops
);
418 #endif /* USE_WIN32API */
420 add_prefix_cmd ("tcp", class_maintenance
, set_tcp_cmd
, _("\
421 TCP protocol specific variables\n\
422 Configure variables specific to remote TCP connections"),
423 &tcp_set_cmdlist
, "set tcp ",
424 0 /* allow-unknown */, &setlist
);
425 add_prefix_cmd ("tcp", class_maintenance
, show_tcp_cmd
, _("\
426 TCP protocol specific variables\n\
427 Configure variables specific to remote TCP connections"),
428 &tcp_show_cmdlist
, "show tcp ",
429 0 /* allow-unknown */, &showlist
);
431 add_setshow_boolean_cmd ("auto-retry", class_obscure
,
432 &tcp_auto_retry
, _("\
433 Set auto-retry on socket connect"), _("\
434 Show auto-retry on socket connect"),
436 &tcp_set_cmdlist
, &tcp_show_cmdlist
);
438 add_setshow_uinteger_cmd ("connect-timeout", class_obscure
,
439 &tcp_retry_limit
, _("\
440 Set timeout limit in seconds for socket connection"), _("\
441 Show timeout limit in seconds for socket connection"), _("\
442 If set to \"unlimited\", GDB will keep attempting to establish a\n\
443 connection forever, unless interrupted with Ctrl-c.\n\
444 The default is 15 seconds."),
446 &tcp_set_cmdlist
, &tcp_show_cmdlist
);