+2011-12-16 Doug Evans <dje@google.com>
+
+ * NEWS: Add entry for stdio gdbserver.
+
2011-12-16 Phil Muldoon <pmuldoon@redhat.com>
* python/python.c: Define python_excp_enums.
*** Changes since GDB 7.4
+* GDBserver now supports stdio connections.
+ E.g. (gdb) target remote | ssh myhost gdbserver - hello
+
*** Changes in GDB 7.4
* GDB now handles ambiguous linespecs more consistently; the existing
+2011-12-16 Doug Evans <dje@google.com>
+
+ * gdb.texinfo (Server): Document -/stdio argument to gdbserver.
+
2011-12-16 Phil Muldoon <pmuldoon@redhat.com>
* gdb.texinfo (Python Commands): Remove "maint set/show print
target> gdbserver @var{comm} @var{program} [ @var{args} @dots{} ]
@end smallexample
-@var{comm} is either a device name (to use a serial line) or a TCP
-hostname and portnumber. For example, to debug Emacs with the argument
+@var{comm} is either a device name (to use a serial line), or a TCP
+hostname and portnumber, or @code{-} or @code{stdio} to use
+stdin/stdout of @code{gdbserver}.
+For example, to debug Emacs with the argument
@samp{foo.txt} and communicate with @value{GDBN} over the serial port
@file{/dev/com1}:
and exits.} You must use the same port number with the host @value{GDBN}
@code{target remote} command.
+The @code{stdio} connection is useful when starting @code{gdbserver}
+with ssh:
+
+@smallexample
+(gdb) target remote | ssh -T hostname gdbserver - hello
+@end smallexample
+
+The @samp{-T} option to ssh is provided because we don't need a remote pty,
+and we don't want escape-character handling. Ssh does this by default when
+a command is provided, the flag is provided to make it explicit.
+You could elide it if you want to.
+
+Programs started with stdio-connected gdbserver have @file{/dev/null} for
+@code{stdin}, and @code{stdout},@code{stderr} are sent back to gdb for
+display through a pipe connected to gdbserver.
+Both @code{stdout} and @code{stderr} use the same pipe.
+
@subsubsection Attaching to a Running Program
@cindex attach to a program, @code{gdbserver}
@cindex @option{--attach}, @code{gdbserver} option
setpgid (0, 0);
+ /* If gdbserver is connected to gdb via stdio, redirect the inferior's
+ stdout to stderr so that inferior i/o doesn't corrupt the connection.
+ Also, redirect stdin to /dev/null. */
+ if (remote_connection_is_stdio ())
+ {
+ close (0);
+ open ("/dev/null", O_RDONLY);
+ dup2 (2, 1);
+ write (2, "stdin/stdout redirected\n",
+ sizeof ("stdin/stdout redirected\n") - 1);
+ }
+
execv (program, allargs);
if (errno == ENOENT)
execvp (program, allargs);
int remote_debug = 0;
struct ui_file *gdb_stdlog;
+static int remote_is_stdio = 0;
+
static gdb_fildes_t remote_desc = INVALID_DESCRIPTOR;
static gdb_fildes_t listen_desc = INVALID_DESCRIPTOR;
return remote_desc != INVALID_DESCRIPTOR;
}
+/* Return true if the remote connection is over stdio. */
+
+int
+remote_connection_is_stdio (void)
+{
+ return remote_is_stdio;
+}
+
static void
enable_async_notification (int fd)
{
socklen_t tmp;
char *port_end;
+ remote_is_stdio = 0;
+ if (strcmp (name, STDIO_CONNECTION_NAME) == 0)
+ {
+ /* We need to record fact that we're using stdio sooner than the
+ call to remote_open so start_inferior knows the connection is
+ via stdio. */
+ remote_is_stdio = 1;
+ transport_is_reliable = 1;
+ return;
+ }
+
port_str = strchr (name, ':');
if (port_str == NULL)
{
char *port_str;
port_str = strchr (name, ':');
+#ifdef USE_WIN32API
if (port_str == NULL)
+ error ("Only <host>:<port> is supported on this platform.");
+#endif
+
+ if (strcmp (name, STDIO_CONNECTION_NAME) == 0)
+ {
+ fprintf (stderr, "Remote debugging using stdio\n");
+
+ /* Use stdin as the handle of the connection.
+ We only select on reads, for example. */
+ remote_desc = fileno (stdin);
+
+ enable_async_notification (remote_desc);
+
+ /* Register the event loop handler. */
+ add_file_handler (remote_desc, handle_serial_event, NULL);
+ }
+#ifndef USE_WIN32API
+ else if (port_str == NULL)
{
-#ifdef USE_WIN32API
- error ("Only <host>:<port> is supported on this platform.");
-#else
struct stat statbuf;
if (stat (name, &statbuf) == 0
/* Register the event loop handler. */
add_file_handler (remote_desc, handle_serial_event, NULL);
-#endif /* USE_WIN32API */
}
+#endif /* USE_WIN32API */
else
{
int port;
#ifdef USE_WIN32API
closesocket (remote_desc);
#else
- close (remote_desc);
+ if (! remote_connection_is_stdio ())
+ close (remote_desc);
#endif
remote_desc = INVALID_DESCRIPTOR;
return ptid_build (pid, tid, 0);
}
+/* Write COUNT bytes in BUF to the client.
+ The result is the number of bytes written or -1 if error.
+ This may return less than COUNT. */
+
+static int
+write_prim (const void *buf, int count)
+{
+ if (remote_connection_is_stdio ())
+ return write (fileno (stdout), buf, count);
+ else
+ return write (remote_desc, buf, count);
+}
+
+/* Read COUNT bytes from the client and store in BUF.
+ The result is the number of bytes read or -1 if error.
+ This may return less than COUNT. */
+
+static int
+read_prim (void *buf, int count)
+{
+ if (remote_connection_is_stdio ())
+ return read (fileno (stdin), buf, count);
+ else
+ return read (remote_desc, buf, count);
+}
+
/* Send a packet to the remote machine, with error checking.
The data of the packet is in BUF, and the length of the
packet is in CNT. Returns >= 0 on success, -1 otherwise. */
do
{
- if (write (remote_desc, buf2, p - buf2) != p - buf2)
+ if (write_prim (buf2, p - buf2) != p - buf2)
{
perror ("putpkt(write)");
free (buf2);
int cc;
char c = 0;
- cc = read (remote_desc, &c, 1);
+ cc = read_prim (&c, 1);
if (cc != 1 || c != '\003' || current_inferior == NULL)
{
if (readchar_bufcnt == 0)
{
- readchar_bufcnt = read (remote_desc, readchar_buf,
- sizeof (readchar_buf));
+ readchar_bufcnt = read_prim (readchar_buf, sizeof (readchar_buf));
if (readchar_bufcnt <= 0)
{
fprintf (stderr, "Bad checksum, sentsum=0x%x, csum=0x%x, buf=%s\n",
(c1 << 4) + c2, csum, buf);
- if (write (remote_desc, "-", 1) != 1)
+ if (write_prim ("-", 1) != 1)
return -1;
}
fflush (stderr);
}
- if (write (remote_desc, "+", 1) != 1)
+ if (write_prim ("+", 1) != 1)
return -1;
if (remote_debug)
}
}
}
+ else if (strcmp (*next_arg, "-") == 0)
+ {
+ /* "-" specifies a stdio connection and is a form of port
+ specification. */
+ *next_arg = STDIO_CONNECTION_NAME;
+ break;
+ }
else if (strcmp (*next_arg, "--disable-randomization") == 0)
disable_randomization = 1;
else if (strcmp (*next_arg, "--no-disable-randomization") == 0)
exit (1);
}
+ /* We need to know whether the remote connection is stdio before
+ starting the inferior. Inferiors created in this scenario have
+ stdin,stdout redirected. So do this here before we call
+ start_inferior. */
+ remote_prepare (port);
+
bad_attach = 0;
pid = 0;
exit (1);
}
- remote_prepare (port);
-
while (1)
{
noack_mode = 0;
int gdb_connected (void);
+#define STDIO_CONNECTION_NAME "stdio"
+int remote_connection_is_stdio (void);
+
ptid_t read_ptid (char *buf, char **obuf);
char *write_ptid (char *buf, ptid_t ptid);
+2011-12-16 Doug Evans <dje@google.com>
+
+ * lib/gdbserver-support.exp (gdb_target_cmd): Recognize stdio
+ gdbserver output.
+ (gdbserver_default_get_remote_address): New function.
+ (gdbserver_start): Call gdb,get_remote_address to compute argument
+ to "target remote" command.
+
2011-12-16 Phil Muldoon <pmuldoon@redhat.com>
* gdb.python/py-function.exp: Change "on" to "full" for
verbose "Set target to $targetname"
return 0
}
+ -re "Remote debugging using stdio.*$gdb_prompt $" {
+ verbose "Set target to $targetname"
+ return 0
+ }
-re "Remote target $targetname connected to.*$gdb_prompt $" {
verbose "Set target to $targetname"
return 0
return $gdbserver_server_exec
}
+# Default routine to compute the argument to "target remote".
+
+proc gdbserver_default_get_remote_address { host port } {
+ return "$host$port"
+}
+
# Start a gdbserver process with initial OPTIONS and trailing ARGUMENTS.
# The port will be filled in between them automatically.
#
set debughost "localhost:"
}
+ # Some boards use a different value for the port that is passed to
+ # gdbserver and the port that is passed to the "target remote" command.
+ # One example is the stdio gdbserver support.
+ if [target_info exists gdb,get_remote_address] {
+ set get_remote_address [target_info gdb,get_remote_address]
+ } else {
+ set get_remote_address gdbserver_default_get_remote_address
+ }
+
# Extract the protocol
if [target_info exists gdb_protocol] {
set protocol [target_info gdb_protocol]
# Loop till we find a free port.
while 1 {
- # Export the host:port pair.
- set gdbport $debughost$portnum
-
# Fire off the debug agent.
set gdbserver_command "$gdbserver"
if { $options != "" } {
append gdbserver_command " $options"
}
-
- append gdbserver_command " :$portnum"
-
+ if { $portnum != "" } {
+ append gdbserver_command " :$portnum"
+ }
if { $arguments != "" } {
append gdbserver_command " $arguments"
}
}
}
- return [list $protocol $gdbport]
+ return [list $protocol [$get_remote_address $debughost $portnum]]
}
# Start a gdbserver process running SERVER_EXEC, and connect GDB