-/* Serial interface for raw TCP connections on Un*x like systems
- Copyright 1992, 1993, 1998 Free Software Foundation, Inc.
+/* Serial interface for raw TCP connections on Un*x like systems.
+
+ 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., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, 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>
-#include <sys/time.h>
+
+#ifdef HAVE_SYS_FILIO_H
+#include <sys/filio.h> /* For FIONBIO. */
+#endif
+#ifdef HAVE_SYS_IOCTL_H
+#include <sys/ioctl.h> /* For FIONBIO. */
+#endif
+
+#include "gdbsupport/gdb_sys_time.h"
+
+#ifdef USE_WIN32API
+#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
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <sys/socket.h>
-#ifdef HAVE_UNISTD_H
-#include <unistd.h>
-#endif
-
-#ifndef __CYGWIN32__
#include <netinet/tcp.h>
#endif
-#include "signals.h"
-#include "gdb_string.h"
+#include <signal.h>
+#include "gdbsupport/gdb_select.h"
+#include <algorithm>
-extern int (*ui_loop_hook) PARAMS ((int));
+#ifndef HAVE_SOCKLEN_T
+typedef int socklen_t;
+#endif
-struct tcp_ttystate
- {
- int bogus;
- };
+/* For "set tcp" and "show tcp". */
-static int tcp_open PARAMS ((serial_t scb, const char *name));
-static void tcp_raw PARAMS ((serial_t scb));
-static int wait_for PARAMS ((serial_t scb, int timeout));
-static int tcp_readchar PARAMS ((serial_t scb, int timeout));
-static int tcp_setbaudrate PARAMS ((serial_t scb, int rate));
-static int tcp_setstopbits PARAMS ((serial_t scb, int num));
-static int tcp_write PARAMS ((serial_t scb, const char *str, int len));
-/* FIXME: static void tcp_restore PARAMS ((serial_t scb)); */
-static void tcp_close PARAMS ((serial_t scb));
-static serial_ttystate tcp_get_tty_state PARAMS ((serial_t scb));
-static int tcp_set_tty_state PARAMS ((serial_t scb, serial_ttystate state));
-static int tcp_return_0 PARAMS ((serial_t));
-static int tcp_noflush_set_tty_state PARAMS ((serial_t, serial_ttystate,
- serial_ttystate));
-static void tcp_print_tty_state PARAMS ((serial_t, serial_ttystate));
+static struct cmd_list_element *tcp_set_cmdlist;
+static struct cmd_list_element *tcp_show_cmdlist;
-void _initialize_ser_tcp PARAMS ((void));
+/* Whether to auto-retry refused connections. */
-/* Open up a raw tcp socket */
+static bool tcp_auto_retry = true;
-static int
-tcp_open (scb, name)
- serial_t scb;
- const char *name;
-{
- char *port_str;
- int port;
- struct hostent *hostent;
- struct sockaddr_in sockaddr;
- int tmp;
- char hostname[100];
- struct protoent *protoent;
- int i;
+/* 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 ("tcp_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. */
- hostent = gethostbyname (hostname);
+static int
+wait_for_connect (int sock, unsigned int *polls)
+{
+ struct timeval t;
+ int n;
- 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;
}
- for (i = 1; i <= 15; i++)
+ /* Check for timeout. */
+ if (*polls > tcp_retry_limit * POLL_INTERVAL)
{
- scb->fd = socket (PF_INET, SOCK_STREAM, 0);
- if (scb->fd < 0)
- return -1;
-
- /* Allow rapid reuse of this port. */
- tmp = 1;
- setsockopt (scb->fd, SOL_SOCKET, SO_REUSEADDR, (char *) &tmp, sizeof (tmp));
-
- /* Enable TCP keep alive process. */
- tmp = 1;
- setsockopt (scb->fd, SOL_SOCKET, SO_KEEPALIVE, (char *) &tmp, sizeof (tmp));
-
- sockaddr.sin_family = PF_INET;
- sockaddr.sin_port = htons (port);
- memcpy (&sockaddr.sin_addr.s_addr, hostent->h_addr,
- sizeof (struct in_addr));
-
- if (!connect (scb->fd, (struct sockaddr *) &sockaddr, sizeof (sockaddr)))
- break;
-
- close (scb->fd);
- scb->fd = -1;
-
-/* We retry for ECONNREFUSED because that is often a temporary condition, which
- happens when the server is being restarted. */
-
- if (errno != ECONNREFUSED)
- return -1;
-
- sleep (1);
+ errno = ETIMEDOUT;
+ return -1;
}
- protoent = getprotobyname ("tcp");
- if (!protoent)
- return -1;
-
- tmp = 1;
- if (setsockopt (scb->fd, protoent->p_proto, TCP_NODELAY,
- (char *) &tmp, sizeof (tmp)))
- return -1;
-
- signal (SIGPIPE, SIG_IGN); /* If we don't do this, then GDB simply exits
- when the remote side dies. */
+ /* 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
+ {
+ t.tv_sec = 1;
+ t.tv_usec = 0;
+ }
- return 0;
+ 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;
+
+ return n;
}
-static serial_ttystate
-tcp_get_tty_state (scb)
- serial_t scb;
-{
- struct tcp_ttystate *state;
-
- state = (struct tcp_ttystate *) xmalloc (sizeof *state);
-
- return (serial_ttystate) state;
-}
+/* 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
-tcp_set_tty_state (scb, ttystate)
- serial_t scb;
- serial_ttystate ttystate;
+try_connect (const struct addrinfo *ainfo, unsigned int *polls)
{
- struct tcp_ttystate *state;
+ int sock = gdb_socket_cloexec (ainfo->ai_family, ainfo->ai_socktype,
+ ainfo->ai_protocol);
- state = (struct tcp_ttystate *) ttystate;
+ if (sock < 0)
+ return -1;
- return 0;
-}
+ /* Set socket nonblocking. */
+#ifdef USE_WIN32API
+ u_long ioarg = 1;
+#else
+ int ioarg = 1;
+#endif
-static int
-tcp_return_0 (scb)
- serial_t scb;
-{
- return 0;
-}
+ ioctl (sock, FIONBIO, &ioarg);
-static void
-tcp_raw (scb)
- serial_t scb;
-{
- return; /* Always in raw mode */
-}
+ /* Use Non-blocking connect. connect() will return 0 if connected
+ already. */
+ if (connect (sock, ainfo->ai_addr, ainfo->ai_addrlen) < 0)
+ {
+#ifdef USE_WIN32API
+ int err = WSAGetLastError();
+#else
+ int err = errno;
+#endif
+
+ /* 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;
+ }
-/* Wait for input on scb, with timeout seconds. Returns 0 on success,
- otherwise SERIAL_TIMEOUT or SERIAL_ERROR.
+ /* Looks like we need to wait for the connect. */
+ int n;
- For termio{s}, we actually just setup VTIME if necessary, and let the
- timeout occur in the read() in tcp_read().
- */
+ do
+ n = wait_for_connect (sock, polls);
+ while (n == 0);
-static int
-wait_for (scb, timeout)
- serial_t scb;
- int timeout;
-{
- int numfds;
- struct timeval tv;
- fd_set readfds, exceptfds;
+ if (n < 0)
+ {
+ int saved_errno = errno;
- FD_ZERO (&readfds);
- FD_ZERO (&exceptfds);
+ /* 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;
+ }
+ }
- tv.tv_sec = timeout;
- tv.tv_usec = 0;
+ /* Got something. Is it an error? */
+ int err;
+ socklen_t len = sizeof (err);
- FD_SET (scb->fd, &readfds);
- FD_SET (scb->fd, &exceptfds);
+ /* 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);
- while (1)
+ if (ret < 0)
{
- if (timeout >= 0)
- numfds = select (scb->fd + 1, &readfds, 0, &exceptfds, &tv);
- else
- numfds = select (scb->fd + 1, &readfds, 0, &exceptfds, 0);
+ int saved_errno = errno;
- if (numfds <= 0)
- {
- if (numfds == 0)
- return SERIAL_TIMEOUT;
- else if (errno == EINTR)
- continue;
- else
- return SERIAL_ERROR; /* Got an error from select or poll */
- }
-
- return 0;
+ close (sock);
+ errno = saved_errno;
+ return -1;
}
+ else if (ret == 0 && err != 0)
+ {
+ close (sock);
+ errno = err;
+ return -1;
+ }
+
+ /* The connection succeeded. Return the socket. */
+ return sock;
}
-/* Read a character with user-specified timeout. TIMEOUT is number of seconds
- to wait, or -1 to wait forever. Use timeout of 0 to effect a poll. Returns
- char if successful. Returns -2 if timeout expired, EOF if line dropped
- dead, or -3 for any other error (see errno in that case). */
+/* Open a tcp socket. */
-static int
-tcp_readchar (scb, timeout)
- serial_t scb;
- int timeout;
+int
+net_open (struct serial *scb, const char *name)
{
- int status;
- int delta;
-
- if (scb->bufcnt-- > 0)
- return *scb->bufp++;
+ struct addrinfo hint;
+ struct addrinfo *ainfo;
- /* We have to be able to keep the GUI alive here, so we break the original
- timeout into steps of 1 second, running the "keep the GUI alive" hook
- each time through the loop.
+ 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;
- Also, timeout = 0 means to poll, so we just set the delta to 0, so we
- will only go through the loop once. */
+ parsed_connection_spec parsed = parse_connection_spec (name, &hint);
- delta = (timeout == 0 ? 0 : 1);
- while (1)
- {
+ if (parsed.port_str.empty ())
+ error (_("Missing port on hostname '%s'"), name);
- /* N.B. The UI may destroy our world (for instance by calling
- remote_stop,) in which case we want to get out of here as
- quickly as possible. It is not safe to touch scb, since
- someone else might have freed it. The ui_loop_hook signals that
- we should exit by returning 1. */
+ int r = getaddrinfo (parsed.host_str.c_str (),
+ parsed.port_str.c_str (),
+ &hint, &ainfo);
- if (ui_loop_hook)
- {
- if (ui_loop_hook (0))
- return SERIAL_TIMEOUT;
- }
+ if (r != 0)
+ {
+ fprintf_unfiltered (gdb_stderr, _("%s: cannot resolve name: %s\n"),
+ name, gai_strerror (r));
+ errno = ENOENT;
+ return -1;
+ }
- status = wait_for (scb, delta);
- timeout -= delta;
+ scoped_free_addrinfo free_ainfo (ainfo);
- /* If we got a character or an error back from wait_for, then we can
- break from the loop before the timeout is completed. */
+ /* 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;
- if (status != SERIAL_TIMEOUT)
- {
- break;
- }
+ /* Assume the worst. */
+ scb->fd = -1;
- /* If we have exhausted the original timeout, then generate
- a SERIAL_TIMEOUT, and pass it out of the loop. */
+ do
+ {
+ got_connrefused = false;
- else if (timeout == 0)
+ for (addrinfo *iter = ainfo; iter != NULL; iter = iter->ai_next)
{
- status == SERIAL_TIMEOUT;
- break;
+ /* 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)
+ {
+ /* We've gotten a successful connection. Save its
+ 'struct addrinfo', the socket, and break. */
+ success_ainfo = iter;
+ scb->fd = sock;
+ break;
+ }
+ else if (
+#ifdef USE_WIN32API
+ errno == WSAECONNREFUSED
+#else
+ errno == ECONNREFUSED
+#endif
+ )
+ got_connrefused = true;
}
}
-
- if (status < 0)
- return status;
-
- while (1)
+ /* 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)
{
- scb->bufcnt = read (scb->fd, scb->buf, BUFSIZ);
- if (scb->bufcnt != -1 || errno != EINTR)
- break;
+ net_close (scb);
+ return -1;
}
- if (scb->bufcnt <= 0)
+ /* Turn off nonblocking. */
+#ifdef USE_WIN32API
+ u_long ioarg = 0;
+#else
+ int ioarg = 0;
+#endif
+
+ ioctl (scb->fd, FIONBIO, &ioarg);
+
+ if (success_ainfo->ai_protocol == IPPROTO_TCP)
{
- if (scb->bufcnt == 0)
- return SERIAL_TIMEOUT; /* 0 chars means timeout [may need to
- distinguish between EOF & timeouts
- someday] */
- else
- return SERIAL_ERROR; /* Got an error from read */
+ /* Disable Nagle algorithm. Needed in some cases. */
+ int tmp = 1;
+
+ setsockopt (scb->fd, IPPROTO_TCP, TCP_NODELAY,
+ (char *) &tmp, sizeof (tmp));
}
- scb->bufcnt--;
- scb->bufp = scb->buf;
- return *scb->bufp++;
-}
+#ifdef SIGPIPE
+ /* If we don't do this, then GDB simply exits
+ when the remote side dies. */
+ signal (SIGPIPE, SIG_IGN);
+#endif
-static int
-tcp_noflush_set_tty_state (scb, new_ttystate, old_ttystate)
- serial_t scb;
- serial_ttystate new_ttystate;
- serial_ttystate old_ttystate;
-{
return 0;
}
-static void
-tcp_print_tty_state (scb, ttystate)
- serial_t scb;
- serial_ttystate ttystate;
+void
+net_close (struct serial *scb)
{
- /* Nothing to print. */
- return;
+ if (scb->fd == -1)
+ return;
+
+ close (scb->fd);
+ scb->fd = -1;
}
-static int
-tcp_setbaudrate (scb, rate)
- serial_t scb;
- int rate;
+int
+net_read_prim (struct serial *scb, size_t count)
{
- return 0; /* Never fails! */
+ /* 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);
}
-static int
-tcp_setstopbits (scb, num)
- serial_t scb;
- int num;
+int
+net_write_prim (struct serial *scb, const void *buf, size_t count)
{
- return 0; /* Never fails! */
+ /* 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);
}
-static int
-tcp_write (scb, str, len)
- serial_t scb;
- const char *str;
- int len;
+int
+ser_tcp_send_break (struct serial *scb)
{
- int cc;
-
- while (len > 0)
- {
- cc = write (scb->fd, str, len);
-
- if (cc < 0)
- return 1;
- len -= cc;
- str += cc;
- }
- return 0;
+ /* Send telnet IAC and BREAK characters. */
+ return (serial_write (scb, "\377\363", 2));
}
-static void
-tcp_close (scb)
- serial_t scb;
-{
- if (scb->fd < 0)
- return;
+#ifndef USE_WIN32API
- close (scb->fd);
- scb->fd = -1;
-}
+/* The TCP ops. */
-static struct serial_ops tcp_ops =
+static const struct serial_ops tcp_ops =
{
"tcp",
- 0,
- tcp_open,
- tcp_close,
- tcp_readchar,
- tcp_write,
- tcp_return_0, /* flush output */
- tcp_return_0, /* flush input */
- tcp_return_0, /* send break */
- tcp_raw,
- tcp_get_tty_state,
- tcp_set_tty_state,
- tcp_print_tty_state,
- tcp_noflush_set_tty_state,
- tcp_setbaudrate,
- tcp_setstopbits,
- tcp_return_0, /* wait for output to drain */
+ 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 ()
{
+#ifdef USE_WIN32API
+ /* Do nothing; the TCP serial operations will be initialized in
+ ser-mingw.c. */
+#else
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