/* Serial interface for raw TCP connections on Un*x like systems.
- Copyright (C) 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2001, 2005, 2006,
- 2007 Free Software Foundation, Inc.
+ Copyright (C) 1992-2020 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
+ the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 51 Franklin Street, Fifth Floor,
- Boston, MA 02110-1301, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "serial.h"
#include "ser-base.h"
#include "ser-tcp.h"
+#include "gdbcmd.h"
+#include "cli/cli-decode.h"
+#include "cli/cli-setshow.h"
+#include "gdbsupport/filestuff.h"
+#include "gdbsupport/netstuff.h"
#include <sys/types.h>
#ifdef HAVE_SYS_FILIO_H
-#include <sys/filio.h> /* For FIONBIO. */
+#include <sys/filio.h> /* For FIONBIO. */
#endif
#ifdef HAVE_SYS_IOCTL_H
-#include <sys/ioctl.h> /* For FIONBIO. */
+#include <sys/ioctl.h> /* For FIONBIO. */
#endif
-#include <sys/time.h>
+#include "gdbsupport/gdb_sys_time.h"
#ifdef USE_WIN32API
-#include <winsock2.h>
+#include <ws2tcpip.h>
+#ifndef ETIMEDOUT
#define ETIMEDOUT WSAETIMEDOUT
+#endif
+/* Gnulib defines close too, but gnulib's replacement
+ doesn't call closesocket unless we import the
+ socketlib module. */
+#undef close
#define close(fd) closesocket (fd)
#define ioctl ioctlsocket
#else
#endif
#include <signal.h>
-#include "gdb_string.h"
+#include "gdbsupport/gdb_select.h"
+#include <algorithm>
#ifndef HAVE_SOCKLEN_T
typedef int socklen_t;
#endif
-void _initialize_ser_tcp (void);
+/* For "set tcp" and "show tcp". */
-/* seconds to wait for connect */
-#define TIMEOUT 15
-/* how many times per second to poll deprecated_ui_loop_hook */
-#define POLL_INTERVAL 2
+static struct cmd_list_element *tcp_set_cmdlist;
+static struct cmd_list_element *tcp_show_cmdlist;
-/* Open a tcp socket */
+/* Whether to auto-retry refused connections. */
-int
-net_open (struct serial *scb, const char *name)
-{
- char *port_str, hostname[100];
- int n, port, tmp;
- int use_udp;
- struct hostent *hostent;
- struct sockaddr_in sockaddr;
-#ifdef USE_WIN32API
- u_long ioarg;
-#else
- int ioarg;
-#endif
+static bool tcp_auto_retry = true;
- use_udp = 0;
- if (strncmp (name, "udp:", 4) == 0)
- {
- use_udp = 1;
- name = name + 4;
- }
- else if (strncmp (name, "tcp:", 4) == 0)
- name = name + 4;
+/* Timeout period for connections, in seconds. */
+
+static unsigned int tcp_retry_limit = 15;
- port_str = strchr (name, ':');
+/* How many times per second to poll deprecated_ui_loop_hook. */
- if (!port_str)
- error (_("net_open: No colon in host name!")); /* Shouldn't ever happen */
+#define POLL_INTERVAL 5
- tmp = min (port_str - name, (int) sizeof hostname - 1);
- strncpy (hostname, name, tmp); /* Don't want colon */
- hostname[tmp] = '\000'; /* Tie off host name */
- port = atoi (port_str + 1);
+/* Helper function to wait a while. If SOCK is not -1, wait on its
+ file descriptor. Otherwise just wait on a timeout, updating
+ *POLLS. Returns -1 on timeout or interrupt, otherwise the value of
+ select. */
- /* default hostname is localhost */
- if (!hostname[0])
- strcpy (hostname, "localhost");
+static int
+wait_for_connect (int sock, unsigned int *polls)
+{
+ struct timeval t;
+ int n;
- hostent = gethostbyname (hostname);
- if (!hostent)
+ /* While we wait for the connect to complete,
+ poll the UI so it can update or the user can
+ interrupt. */
+ if (deprecated_ui_loop_hook && deprecated_ui_loop_hook (0))
{
- fprintf_unfiltered (gdb_stderr, "%s: unknown host\n", hostname);
- errno = ENOENT;
+ errno = EINTR;
+ return -1;
+ }
+
+ /* Check for timeout. */
+ if (*polls > tcp_retry_limit * POLL_INTERVAL)
+ {
+ errno = ETIMEDOUT;
return -1;
}
- if (use_udp)
- scb->fd = socket (PF_INET, SOCK_DGRAM, 0);
+ /* Back off to polling once per second after the first POLL_INTERVAL
+ polls. */
+ if (*polls < POLL_INTERVAL)
+ {
+ t.tv_sec = 0;
+ t.tv_usec = 1000000 / POLL_INTERVAL;
+ }
else
- scb->fd = socket (PF_INET, SOCK_STREAM, 0);
+ {
+ t.tv_sec = 1;
+ t.tv_usec = 0;
+ }
- if (scb->fd < 0)
- return -1;
-
- sockaddr.sin_family = PF_INET;
- sockaddr.sin_port = htons (port);
- memcpy (&sockaddr.sin_addr.s_addr, hostent->h_addr,
- sizeof (struct in_addr));
-
- /* set socket nonblocking */
- ioarg = 1;
- ioctl (scb->fd, FIONBIO, &ioarg);
+ if (sock >= 0)
+ {
+ fd_set rset, wset, eset;
+
+ FD_ZERO (&rset);
+ FD_SET (sock, &rset);
+ wset = rset;
+ eset = rset;
+
+ /* POSIX systems return connection success or failure by signalling
+ wset. Windows systems return success in wset and failure in
+ eset.
+
+ We must call select here, rather than gdb_select, because
+ the serial structure has not yet been initialized - the
+ MinGW select wrapper will not know that this FD refers
+ to a socket. */
+ n = select (sock + 1, &rset, &wset, &eset, &t);
+ }
+ else
+ /* Use gdb_select here, since we have no file descriptors, and on
+ Windows, plain select doesn't work in that case. */
+ n = gdb_select (0, NULL, NULL, NULL, &t);
+
+ /* If we didn't time out, only count it as one poll. */
+ if (n > 0 || *polls < POLL_INTERVAL)
+ (*polls)++;
+ else
+ (*polls) += POLL_INTERVAL;
- /* Use Non-blocking connect. connect() will return 0 if connected already. */
- n = connect (scb->fd, (struct sockaddr *) &sockaddr, sizeof (sockaddr));
+ return n;
+}
+
+/* Try to connect to the host represented by AINFO. If the connection
+ succeeds, return its socket. Otherwise, return -1 and set ERRNO
+ accordingly. POLLS is used when 'connect' returns EINPROGRESS, and
+ we need to invoke 'wait_for_connect' to obtain the status. */
+
+static int
+try_connect (const struct addrinfo *ainfo, unsigned int *polls)
+{
+ int sock = gdb_socket_cloexec (ainfo->ai_family, ainfo->ai_socktype,
+ ainfo->ai_protocol);
- if (n < 0
+ if (sock < 0)
+ return -1;
+
+ /* Set socket nonblocking. */
#ifdef USE_WIN32API
- /* Under Windows, calling "connect" with a non-blocking socket
- results in WSAEWOULDBLOCK, not WSAEINPROGRESS. */
- && WSAGetLastError() != WSAEWOULDBLOCK
+ u_long ioarg = 1;
#else
- && errno != EINPROGRESS
+ int ioarg = 1;
#endif
- )
+
+ ioctl (sock, FIONBIO, &ioarg);
+
+ /* Use Non-blocking connect. connect() will return 0 if connected
+ already. */
+ if (connect (sock, ainfo->ai_addr, ainfo->ai_addrlen) < 0)
{
#ifdef USE_WIN32API
- errno = WSAGetLastError();
+ int err = WSAGetLastError();
+#else
+ int err = errno;
#endif
- net_close (scb);
+
+ /* If we've got a "connection refused" error, just return
+ -1. The caller will know what to do. */
+ if (
+#ifdef USE_WIN32API
+ err == WSAECONNREFUSED
+#else
+ err == ECONNREFUSED
+#endif
+ )
+ {
+ close (sock);
+ errno = err;
+ return -1;
+ }
+
+ if (
+ /* Any other error (except EINPROGRESS) will be "swallowed"
+ here. We return without specifying a return value, and
+ set errno if the caller wants to inspect what
+ happened. */
+#ifdef USE_WIN32API
+ /* Under Windows, calling "connect" with a non-blocking socket
+ results in WSAEWOULDBLOCK, not WSAEINPROGRESS. */
+ err != WSAEWOULDBLOCK
+#else
+ err != EINPROGRESS
+#endif
+ )
+ {
+ close (sock);
+ errno = err;
+ return -1;
+ }
+
+ /* Looks like we need to wait for the connect. */
+ int n;
+
+ do
+ n = wait_for_connect (sock, polls);
+ while (n == 0);
+
+ if (n < 0)
+ {
+ int saved_errno = errno;
+
+ /* A negative value here means that we either timed out or
+ got interrupted by the user. Just return. */
+ close (sock);
+ errno = saved_errno;
+ return -1;
+ }
+ }
+
+ /* Got something. Is it an error? */
+ int err;
+ socklen_t len = sizeof (err);
+
+ /* On Windows, the fourth parameter to getsockopt is a "char *";
+ on UNIX systems it is generally "void *". The cast to "char *"
+ is OK everywhere, since in C++ any data pointer type can be
+ implicitly converted to "void *". */
+ int ret = getsockopt (sock, SOL_SOCKET, SO_ERROR, (char *) &err, &len);
+
+ if (ret < 0)
+ {
+ int saved_errno = errno;
+
+ close (sock);
+ errno = saved_errno;
+ return -1;
+ }
+ else if (ret == 0 && err != 0)
+ {
+ close (sock);
+ errno = err;
return -1;
}
- if (n)
+ /* The connection succeeded. Return the socket. */
+ return sock;
+}
+
+/* Open a tcp socket. */
+
+int
+net_open (struct serial *scb, const char *name)
+{
+ struct addrinfo hint;
+ struct addrinfo *ainfo;
+
+ memset (&hint, 0, sizeof (hint));
+ /* Assume no prefix will be passed, therefore we should use
+ AF_UNSPEC. */
+ hint.ai_family = AF_UNSPEC;
+ hint.ai_socktype = SOCK_STREAM;
+ hint.ai_protocol = IPPROTO_TCP;
+
+ parsed_connection_spec parsed = parse_connection_spec (name, &hint);
+
+ if (parsed.port_str.empty ())
+ error (_("Missing port on hostname '%s'"), name);
+
+ int r = getaddrinfo (parsed.host_str.c_str (),
+ parsed.port_str.c_str (),
+ &hint, &ainfo);
+
+ if (r != 0)
{
- /* looks like we need to wait for the connect */
- struct timeval t;
- fd_set rset, wset, eset;
- int polls = 0;
- FD_ZERO (&rset);
+ fprintf_unfiltered (gdb_stderr, _("%s: cannot resolve name: %s\n"),
+ name, gai_strerror (r));
+ errno = ENOENT;
+ return -1;
+ }
+
+ scoped_free_addrinfo free_ainfo (ainfo);
+
+ /* Flag to indicate whether we've got a connection refused. It will
+ be true if any of the connections tried was refused. */
+ bool got_connrefused;
+ /* If a connection succeeds, SUCCESS_AINFO will point to the
+ 'struct addrinfo' that succeed. */
+ struct addrinfo *success_ainfo = NULL;
+ unsigned int polls = 0;
- do
+ /* Assume the worst. */
+ scb->fd = -1;
+
+ do
+ {
+ got_connrefused = false;
+
+ for (addrinfo *iter = ainfo; iter != NULL; iter = iter->ai_next)
{
- /* While we wait for the connect to complete,
- poll the UI so it can update or the user can
- interrupt. */
- if (deprecated_ui_loop_hook)
+ /* Iterate over the list of possible addresses to connect
+ to. For each, we'll try to connect and see if it
+ succeeds. */
+ int sock = try_connect (iter, &polls);
+
+ if (sock >= 0)
{
- if (deprecated_ui_loop_hook (0))
- {
- errno = EINTR;
- net_close (scb);
- return -1;
- }
+ /* We've gotten a successful connection. Save its
+ 'struct addrinfo', the socket, and break. */
+ success_ainfo = iter;
+ scb->fd = sock;
+ break;
}
-
- FD_SET (scb->fd, &rset);
- wset = rset;
- eset = rset;
- t.tv_sec = 0;
- t.tv_usec = 1000000 / POLL_INTERVAL;
-
- /* POSIX systems return connection success or failure by signalling
- wset. Windows systems return success in wset and failure in
- eset.
-
- We must call select here, rather than gdb_select, because
- the serial structure has not yet been initialized - the
- MinGW select wrapper will not know that this FD refers
- to a socket. */
- n = select (scb->fd + 1, &rset, &wset, &eset, &t);
- polls++;
- }
- while (n == 0 && polls <= TIMEOUT * POLL_INTERVAL);
- if (n < 0 || polls > TIMEOUT * POLL_INTERVAL)
- {
- if (polls > TIMEOUT * POLL_INTERVAL)
- errno = ETIMEDOUT;
- net_close (scb);
- return -1;
+ else if (
+#ifdef USE_WIN32API
+ errno == WSAECONNREFUSED
+#else
+ errno == ECONNREFUSED
+#endif
+ )
+ got_connrefused = true;
}
}
+ /* Just retry if:
+
+ - tcp_auto_retry is true, and
+ - We haven't gotten a connection yet, and
+ - Any of our connection attempts returned with ECONNREFUSED, and
+ - wait_for_connect signals that we can keep going. */
+ while (tcp_auto_retry
+ && success_ainfo == NULL
+ && got_connrefused
+ && wait_for_connect (-1, &polls) >= 0);
+
+ if (success_ainfo == NULL)
+ {
+ net_close (scb);
+ return -1;
+ }
- /* Got something. Is it an error? */
- {
- int res, err;
- socklen_t len;
- len = sizeof (err);
- /* On Windows, the fourth parameter to getsockopt is a "char *";
- on UNIX systems it is generally "void *". The cast to "void *"
- is OK everywhere, since in C "void *" can be implicitly
- converted to any pointer type. */
- res = getsockopt (scb->fd, SOL_SOCKET, SO_ERROR, (void *) &err, &len);
- if (res < 0 || err)
- {
- if (err)
- errno = err;
- net_close (scb);
- return -1;
- }
- }
+ /* Turn off nonblocking. */
+#ifdef USE_WIN32API
+ u_long ioarg = 0;
+#else
+ int ioarg = 0;
+#endif
- /* turn off nonblocking */
- ioarg = 0;
ioctl (scb->fd, FIONBIO, &ioarg);
- if (use_udp == 0)
+ if (success_ainfo->ai_protocol == IPPROTO_TCP)
{
- /* Disable Nagle algorithm. Needed in some cases. */
- tmp = 1;
+ /* Disable Nagle algorithm. Needed in some cases. */
+ int tmp = 1;
+
setsockopt (scb->fd, IPPROTO_TCP, TCP_NODELAY,
- (char *)&tmp, sizeof (tmp));
+ (char *) &tmp, sizeof (tmp));
}
#ifdef SIGPIPE
void
net_close (struct serial *scb)
{
- if (scb->fd < 0)
+ if (scb->fd == -1)
return;
close (scb->fd);
int
net_read_prim (struct serial *scb, size_t count)
{
- return recv (scb->fd, scb->buf, count, 0);
+ /* Need to cast to silence -Wpointer-sign on MinGW, as Winsock's
+ 'recv' takes 'char *' as second argument, while 'scb->buf' is
+ 'unsigned char *'. */
+ return recv (scb->fd, (char *) scb->buf, count, 0);
}
int
net_write_prim (struct serial *scb, const void *buf, size_t count)
{
- return send (scb->fd, buf, count, 0);
+ /* On Windows, the second parameter to send is a "const char *"; on
+ UNIX systems it is generally "const void *". The cast to "const
+ char *" is OK everywhere, since in C++ any data pointer type can
+ be implicitly converted to "const void *". */
+ return send (scb->fd, (const char *) buf, count, 0);
+}
+
+int
+ser_tcp_send_break (struct serial *scb)
+{
+ /* Send telnet IAC and BREAK characters. */
+ return (serial_write (scb, "\377\363", 2));
}
+#ifndef USE_WIN32API
+
+/* The TCP ops. */
+
+static const struct serial_ops tcp_ops =
+{
+ "tcp",
+ net_open,
+ net_close,
+ NULL,
+ ser_base_readchar,
+ ser_base_write,
+ ser_base_flush_output,
+ ser_base_flush_input,
+ ser_tcp_send_break,
+ ser_base_raw,
+ ser_base_get_tty_state,
+ ser_base_copy_tty_state,
+ ser_base_set_tty_state,
+ ser_base_print_tty_state,
+ ser_base_setbaudrate,
+ ser_base_setstopbits,
+ ser_base_setparity,
+ ser_base_drain_output,
+ ser_base_async,
+ net_read_prim,
+ net_write_prim
+};
+
+#endif /* USE_WIN32API */
+
+void _initialize_ser_tcp ();
void
-_initialize_ser_tcp (void)
+_initialize_ser_tcp ()
{
#ifdef USE_WIN32API
/* Do nothing; the TCP serial operations will be initialized in
ser-mingw.c. */
- return;
#else
- struct serial_ops *ops;
- ops = XMALLOC (struct serial_ops);
- memset (ops, 0, sizeof (struct serial_ops));
- ops->name = "tcp";
- ops->next = 0;
- ops->open = net_open;
- ops->close = net_close;
- ops->readchar = ser_base_readchar;
- ops->write = ser_base_write;
- ops->flush_output = ser_base_flush_output;
- ops->flush_input = ser_base_flush_input;
- ops->send_break = ser_base_send_break;
- ops->go_raw = ser_base_raw;
- ops->get_tty_state = ser_base_get_tty_state;
- ops->set_tty_state = ser_base_set_tty_state;
- ops->print_tty_state = ser_base_print_tty_state;
- ops->noflush_set_tty_state = ser_base_noflush_set_tty_state;
- ops->setbaudrate = ser_base_setbaudrate;
- ops->setstopbits = ser_base_setstopbits;
- ops->drain_output = ser_base_drain_output;
- ops->async = ser_base_async;
- ops->read_prim = net_read_prim;
- ops->write_prim = net_write_prim;
- serial_add_interface (ops);
+ serial_add_interface (&tcp_ops);
#endif /* USE_WIN32API */
+
+ add_basic_prefix_cmd ("tcp", class_maintenance, _("\
+TCP protocol specific variables.\n\
+Configure variables specific to remote TCP connections."),
+ &tcp_set_cmdlist, "set tcp ",
+ 0 /* allow-unknown */, &setlist);
+ add_show_prefix_cmd ("tcp", class_maintenance, _("\
+TCP protocol specific variables.\n\
+Configure variables specific to remote TCP connections."),
+ &tcp_show_cmdlist, "show tcp ",
+ 0 /* allow-unknown */, &showlist);
+
+ add_setshow_boolean_cmd ("auto-retry", class_obscure,
+ &tcp_auto_retry, _("\
+Set auto-retry on socket connect."), _("\
+Show auto-retry on socket connect."),
+ NULL, NULL, NULL,
+ &tcp_set_cmdlist, &tcp_show_cmdlist);
+
+ add_setshow_uinteger_cmd ("connect-timeout", class_obscure,
+ &tcp_retry_limit, _("\
+Set timeout limit in seconds for socket connection."), _("\
+Show timeout limit in seconds for socket connection."), _("\
+If set to \"unlimited\", GDB will keep attempting to establish a\n\
+connection forever, unless interrupted with Ctrl-c.\n\
+The default is 15 seconds."),
+ NULL, NULL,
+ &tcp_set_cmdlist, &tcp_show_cmdlist);
}
projects / deliverable / binutils-gdb.git / blobdiff