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 void _initialize_ser_tcp (void);
65 /* For "set tcp" and "show tcp". */
67 static struct cmd_list_element *tcp_set_cmdlist;
68 static struct cmd_list_element *tcp_show_cmdlist;
70 /* Whether to auto-retry refused connections. */
72 static int tcp_auto_retry = 1;
74 /* Timeout period for connections, in seconds. */
76 static unsigned int tcp_retry_limit = 15;
78 /* How many times per second to poll deprecated_ui_loop_hook. */
80 #define POLL_INTERVAL 5
82 /* Helper function to wait a while. If SCB is non-null, wait on its
83 file descriptor. Otherwise just wait on a timeout, updating *POLLS.
84 Returns -1 on timeout or interrupt, otherwise the value of select. */
87 wait_for_connect (struct serial *scb, unsigned int *polls)
92 /* While we wait for the connect to complete,
93 poll the UI so it can update or the user can
95 if (deprecated_ui_loop_hook && deprecated_ui_loop_hook (0))
101 /* Check for timeout. */
102 if (*polls > tcp_retry_limit * POLL_INTERVAL)
108 /* Back off to polling once per second after the first POLL_INTERVAL
110 if (*polls < POLL_INTERVAL)
113 t.tv_usec = 1000000 / POLL_INTERVAL;
123 fd_set rset, wset, eset;
126 FD_SET (scb->fd, &rset);
130 /* POSIX systems return connection success or failure by signalling
131 wset. Windows systems return success in wset and failure in
134 We must call select here, rather than gdb_select, because
135 the serial structure has not yet been initialized - the
136 MinGW select wrapper will not know that this FD refers
138 n = select (scb->fd + 1, &rset, &wset, &eset, &t);
141 /* Use gdb_select here, since we have no file descriptors, and on
142 Windows, plain select doesn't work in that case. */
143 n = gdb_select (0, NULL, NULL, NULL, &t);
145 /* If we didn't time out, only count it as one poll. */
146 if (n > 0 || *polls < POLL_INTERVAL)
149 (*polls) += POLL_INTERVAL;
154 /* Open a tcp socket. */
157 net_open (struct serial *scb, const char *name)
160 const char *port_str;
163 struct hostent *hostent;
164 struct sockaddr_in sockaddr;
170 unsigned int polls = 0;
173 if (startswith (name, "udp:"))
178 else if (startswith (name, "tcp:"))
181 port_str = strchr (name, ':');
184 error (_("net_open: No colon in host name!")); /* Shouldn't ever
187 tmp = std::min (port_str - name, (ptrdiff_t) sizeof hostname - 1);
188 strncpy (hostname, name, tmp); /* Don't want colon. */
189 hostname[tmp] = '\000'; /* Tie off host name. */
190 port = atoi (port_str + 1);
192 /* Default hostname is localhost. */
194 strcpy (hostname, "localhost");
196 hostent = gethostbyname (hostname);
199 fprintf_unfiltered (gdb_stderr, "%s: unknown host\n", hostname);
204 sockaddr.sin_family = PF_INET;
205 sockaddr.sin_port = htons (port);
206 memcpy (&sockaddr.sin_addr.s_addr, hostent->h_addr,
207 sizeof (struct in_addr));
212 scb->fd = gdb_socket_cloexec (PF_INET, SOCK_DGRAM, 0);
214 scb->fd = gdb_socket_cloexec (PF_INET, SOCK_STREAM, 0);
219 /* Set socket nonblocking. */
221 ioctl (scb->fd, FIONBIO, &ioarg);
223 /* Use Non-blocking connect. connect() will return 0 if connected
225 n = connect (scb->fd, (struct sockaddr *) &sockaddr, sizeof (sockaddr));
230 int err = WSAGetLastError();
235 /* Maybe we're waiting for the remote target to become ready to
236 accept connections. */
239 && err == WSAECONNREFUSED
241 && err == ECONNREFUSED
243 && wait_for_connect (NULL, &polls) >= 0)
251 /* Under Windows, calling "connect" with a non-blocking socket
252 results in WSAEWOULDBLOCK, not WSAEINPROGRESS. */
253 err != WSAEWOULDBLOCK
264 /* Looks like we need to wait for the connect. */
267 n = wait_for_connect (scb, &polls);
277 /* Got something. Is it an error? */
283 /* On Windows, the fourth parameter to getsockopt is a "char *";
284 on UNIX systems it is generally "void *". The cast to "char *"
285 is OK everywhere, since in C++ any data pointer type can be
286 implicitly converted to "void *". */
287 res = getsockopt (scb->fd, SOL_SOCKET, SO_ERROR, (char *) &err, &len);
290 /* Maybe the target still isn't ready to accept the connection. */
293 && err == WSAECONNREFUSED
295 && err == ECONNREFUSED
297 && wait_for_connect (NULL, &polls) >= 0)
309 /* Turn off nonblocking. */
311 ioctl (scb->fd, FIONBIO, &ioarg);
315 /* Disable Nagle algorithm. Needed in some cases. */
317 setsockopt (scb->fd, IPPROTO_TCP, TCP_NODELAY,
318 (char *)&tmp, sizeof (tmp));
322 /* If we don't do this, then GDB simply exits
323 when the remote side dies. */
324 signal (SIGPIPE, SIG_IGN);
331 net_close (struct serial *scb)
341 net_read_prim (struct serial *scb, size_t count)
343 /* Need to cast to silence -Wpointer-sign on MinGW, as Winsock's
344 'recv' takes 'char *' as second argument, while 'scb->buf' is
345 'unsigned char *'. */
346 return recv (scb->fd, (char *) scb->buf, count, 0);
350 net_write_prim (struct serial *scb, const void *buf, size_t count)
352 /* On Windows, the second parameter to send is a "const char *"; on
353 UNIX systems it is generally "const void *". The cast to "const
354 char *" is OK everywhere, since in C++ any data pointer type can
355 be implicitly converted to "const void *". */
356 return send (scb->fd, (const char *) buf, count, 0);
360 ser_tcp_send_break (struct serial *scb)
362 /* Send telnet IAC and BREAK characters. */
363 return (serial_write (scb, "\377\363", 2));
366 /* Support for "set tcp" and "show tcp" commands. */
369 set_tcp_cmd (char *args, int from_tty)
371 help_list (tcp_set_cmdlist, "set tcp ", all_commands, gdb_stdout);
375 show_tcp_cmd (char *args, int from_tty)
377 help_list (tcp_show_cmdlist, "show tcp ", all_commands, gdb_stdout);
384 static const struct serial_ops tcp_ops =
392 ser_base_flush_output,
393 ser_base_flush_input,
396 ser_base_get_tty_state,
397 ser_base_copy_tty_state,
398 ser_base_set_tty_state,
399 ser_base_print_tty_state,
400 ser_base_noflush_set_tty_state,
401 ser_base_setbaudrate,
402 ser_base_setstopbits,
404 ser_base_drain_output,
410 #endif /* USE_WIN32API */
413 _initialize_ser_tcp (void)
416 /* Do nothing; the TCP serial operations will be initialized in
419 serial_add_interface (&tcp_ops);
420 #endif /* USE_WIN32API */
422 add_prefix_cmd ("tcp", class_maintenance, set_tcp_cmd, _("\
423 TCP protocol specific variables\n\
424 Configure variables specific to remote TCP connections"),
425 &tcp_set_cmdlist, "set tcp ",
426 0 /* allow-unknown */, &setlist);
427 add_prefix_cmd ("tcp", class_maintenance, show_tcp_cmd, _("\
428 TCP protocol specific variables\n\
429 Configure variables specific to remote TCP connections"),
430 &tcp_show_cmdlist, "show tcp ",
431 0 /* allow-unknown */, &showlist);
433 add_setshow_boolean_cmd ("auto-retry", class_obscure,
434 &tcp_auto_retry, _("\
435 Set auto-retry on socket connect"), _("\
436 Show auto-retry on socket connect"),
438 &tcp_set_cmdlist, &tcp_show_cmdlist);
440 add_setshow_uinteger_cmd ("connect-timeout", class_obscure,
441 &tcp_retry_limit, _("\
442 Set timeout limit in seconds for socket connection"), _("\
443 Show timeout limit in seconds for socket connection"), _("\
444 If set to \"unlimited\", GDB will keep attempting to establish a\n\
445 connection forever, unless interrupted with Ctrl-c.\n\
446 The default is 15 seconds."),
448 &tcp_set_cmdlist, &tcp_show_cmdlist);