target system. If it is not set, the target will use a default
filename (e.g.@: the last program run).
+@item set remote interrupt-sequence
+@cindex interrupt remote programs
+@cindex select Ctrl-C, BREAK or BREAK-g
+Allow the user to select one of @samp{Ctrl-C}, a @code{BREAK} or
+@samp{BREAK-g} as the
+sequence to the remote target in order to interrupt the execution.
+@samp{Ctrl-C} is a default. Some system prefers @code{BREAK} which
+is high level of serial line for some certain time.
+Linux kernel prefers @samp{BREAK-g}, a.k.a Magic SysRq g.
+It is @code{BREAK} signal followed by character @code{g}.
+
+@item show interrupt-sequence
+Show which of @samp{Ctrl-C}, @code{BREAK} or @code{BREAK-g}
+is sent by @value{GDBN} to interrupt the remote program.
+@code{BREAK-g} is BREAK signal followed by @code{g} and
+also known as Magic SysRq g.
+
+@item set remote interrupt-on-connect
+@cindex send interrupt-sequence on start
+Specify whether interrupt-sequence is sent to remote target when
+@value{GDBN} connects to it. This is mostly needed when you debug
+Linux kernel. Linux kernel expects @code{BREAK} followed by @code{g}
+which is known as Magic SysRq g in order to connect @value{GDBN}.
+
+@item show interrupt-on-connect
+Show whether interrupt-sequence is sent
+to remote target when @value{GDBN} connects to it.
+
@kindex set tcp
@kindex show tcp
@item set tcp auto-retry on
@cindex interrupts (remote protocol)
When a program on the remote target is running, @value{GDBN} may
-attempt to interrupt it by sending a @samp{Ctrl-C} or a @code{BREAK},
-control of which is specified via @value{GDBN}'s @samp{remotebreak}
-setting (@pxref{set remotebreak}).
+attempt to interrupt it by sending a @samp{Ctrl-C}, @code{BREAK} or
+a @code{BREAK} followed by @code{g},
+control of which is specified via @value{GDBN}'s @samp{interrupt-sequence}.
The precise meaning of @code{BREAK} is defined by the transport
mechanism and may, in fact, be undefined. @value{GDBN} does not
(@pxref{X packet}), used for binary downloads, may include an unescaped
@code{0x03} as part of its packet.
+@code{BREAK} followed by @code{g} is also known as Magic SysRq g.
+When Linux kernel receives this sequence from serial port,
+it stops execution and connects to gdb.
+
Stubs are not required to recognize these interrupt mechanisms and the
precise meaning associated with receipt of the interrupt is
implementation defined. If the target supports debugging of multiple
this can go away. */
static int wait_forever_enabled_p = 1;
+/* Allow the user to specify what sequence to send to the remote
+ when he requests a program interruption: Although ^C is usually
+ what remote systems expect (this is the default, here), it is
+ sometimes preferable to send a break. On other systems such
+ as the Linux kernel, a break followed by g, which is Magic SysRq g
+ is required in order to interrupt the execution. */
+const char interrupt_sequence_control_c[] = "Ctrl-C";
+const char interrupt_sequence_break[] = "BREAK";
+const char interrupt_sequence_break_g[] = "BREAK-g";
+static const char *interrupt_sequence_modes[] =
+ {
+ interrupt_sequence_control_c,
+ interrupt_sequence_break,
+ interrupt_sequence_break_g,
+ NULL
+ };
+static const char *interrupt_sequence_mode = interrupt_sequence_control_c;
+
+static void
+show_interrupt_sequence (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c,
+ const char *value)
+{
+ if (interrupt_sequence_mode == interrupt_sequence_control_c)
+ fprintf_filtered (file,
+ _("Send the ASCII ETX character (Ctrl-c) "
+ "to the remote target to interrupt the "
+ "execution of the program.\n"));
+ else if (interrupt_sequence_mode == interrupt_sequence_break)
+ fprintf_filtered (file,
+ _("send a break signal to the remote target "
+ "to interrupt the execution of the program.\n"));
+ else if (interrupt_sequence_mode == interrupt_sequence_break_g)
+ fprintf_filtered (file,
+ _("Send a break signal and 'g' a.k.a. Magic SysRq g to "
+ "the remote target to interrupt the execution "
+ "of Linux kernel.\n"));
+ else
+ internal_error (__FILE__, __LINE__,
+ _("Invalid value for interrupt_sequence_mode: %s."),
+ interrupt_sequence_mode);
+}
-/* This variable chooses whether to send a ^C or a break when the user
- requests program interruption. Although ^C is usually what remote
- systems expect, and that is the default here, sometimes a break is
- preferable instead. */
+/* This boolean variable specifies whether interrupt_sequence is sent
+ to the remote target when gdb connects to it.
+ This is mostly needed when you debug the Linux kernel: The Linux kernel
+ expects BREAK g which is Magic SysRq g for connecting gdb. */
+static int interrupt_on_connect = 0;
+/* This variable is used to implement the "set/show remotebreak" commands.
+ Since these commands are now deprecated in favor of "set/show remote
+ interrupt-sequence", it no longer has any effect on the code. */
static int remote_break;
+static void
+set_remotebreak (char *args, int from_tty, struct cmd_list_element *c)
+{
+ if (remote_break)
+ interrupt_sequence_mode = interrupt_sequence_break;
+ else
+ interrupt_sequence_mode = interrupt_sequence_control_c;
+}
+
+static void
+show_remotebreak (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c,
+ const char *value)
+{
+}
+
/* Descriptor for I/O to remote machine. Initialize it to NULL so that
remote_open knows that we don't have a file open when the program
starts. */
int extended_p;
};
+/* Send interrupt_sequence to remote target. */
+static void
+send_interrupt_sequence ()
+{
+ if (interrupt_sequence_mode == interrupt_sequence_control_c)
+ serial_write (remote_desc, "\x03", 1);
+ else if (interrupt_sequence_mode == interrupt_sequence_break)
+ serial_send_break (remote_desc);
+ else if (interrupt_sequence_mode == interrupt_sequence_break_g)
+ {
+ serial_send_break (remote_desc);
+ serial_write (remote_desc, "g", 1);
+ }
+ else
+ internal_error (__FILE__, __LINE__,
+ _("Invalid value for interrupt_sequence_mode: %s."),
+ interrupt_sequence_mode);
+}
+
static void
remote_start_remote (struct ui_out *uiout, void *opaque)
{
/* Ack any packet which the remote side has already sent. */
serial_write (remote_desc, "+", 1);
+ if (interrupt_on_connect)
+ send_interrupt_sequence ();
+
/* The first packet we send to the target is the optional "supported
packets" request. If the target can answer this, it will tell us
which later probes to skip. */
if (rs->cached_wait_status)
return;
- /* Send a break or a ^C, depending on user preference. */
-
- if (remote_break)
- serial_send_break (remote_desc);
- else
- serial_write (remote_desc, "\003", 1);
+ /* Send interrupt_sequence to remote target. */
+ send_interrupt_sequence ();
}
/* This is the generic stop called via the target vector. When a target
_initialize_remote (void)
{
struct remote_state *rs;
+ struct cmd_list_element *cmd;
+ char *cmd_name;
/* architecture specific data */
remote_gdbarch_data_handle =
Set whether to send break if interrupted."), _("\
Show whether to send break if interrupted."), _("\
If set, a break, instead of a cntrl-c, is sent to the remote target."),
- NULL, NULL, /* FIXME: i18n: Whether to send break if interrupted is %s. */
+ set_remotebreak, show_remotebreak,
&setlist, &showlist);
+ cmd_name = "remotebreak";
+ cmd = lookup_cmd (&cmd_name, setlist, "", -1, 1);
+ deprecate_cmd (cmd, "set remote interrupt-sequence");
+ cmd_name = "remotebreak"; /* needed because lookup_cmd updates the pointer */
+ cmd = lookup_cmd (&cmd_name, showlist, "", -1, 1);
+ deprecate_cmd (cmd, "show remote interrupt-sequence");
+
+ add_setshow_enum_cmd ("interrupt-sequence", class_support,
+ interrupt_sequence_modes, &interrupt_sequence_mode, _("\
+Set interrupt sequence to remote target."), _("\
+Show interrupt sequence to remote target."), _("\
+Valid value is \"Ctrl-C\", \"BREAK\" or \"BREAK-g\". The default is \"Ctrl-C\"."),
+ NULL, show_interrupt_sequence,
+ &remote_set_cmdlist,
+ &remote_show_cmdlist);
+
+ add_setshow_boolean_cmd ("interrupt-on-connect", class_support,
+ &interrupt_on_connect, _("\
+Set whether interrupt-sequence is sent to remote target when gdb connects to."), _(" \
+Show whether interrupt-sequence is sent to remote target when gdb connects to."), _(" \
+If set, interrupt sequence is sent to remote target."),
+ NULL, NULL,
+ &remote_set_cmdlist, &remote_show_cmdlist);
/* Install commands for configuring memory read/write packets. */