Files
binutils-gdb/gdb/tui/tui-interp.c
Antoine Tremblay 4034d0ff52 Emit inferior, thread and frame selection events to all UIs
With this patch, when an inferior, thread or frame is explicitly
selected by the user, notifications will appear on all CLI and MI UIs.
When a GDB console is integrated in a front-end, this allows the
front-end to follow a selection made by the user ont he CLI, and it
informs the user about selection changes made behind the scenes by the
front-end.

This patch addresses PR gdb/20487.

In order to communicate frame changes to the front-end, this patch adds
a new field to the =thread-selected event for the selected frame.  The
idea is that since inferior/thread/frame can be seen as a composition,
it makes sense to send them together in the same event.  The vision
would be to eventually send the inferior information as well, if we find
that it's needed, although the "=thread-selected" event would be
ill-named for that job.

Front-ends need to handle this new field if they want to follow the
frame selection changes that originate from the console.  The format of
the frame attribute is the same as what is found in the *stopped events.

Here's a detailed example for each command and the events they generate:

thread
------

1. CLI command:

     thread 1.3

   MI event:

     =thread-selected,id="3",frame={...}

2. MI command:

     -thread-select 3

   CLI event:

     [Switching to thread 1.3 ...]

3. MI command (CLI-in-MI):

     thread 1.3

   MI event/reply:

     &"thread 1.3\n"
     ~"#0  child_sub_function () ...
     =thread-selected,id="3",frame={level="0",...}
     ^done

frame
-----

1. CLI command:

     frame 1

   MI event:

     =thread-selected,id="3",frame={level="1",...}

2. MI command:

     -stack-select-frame 1

   CLI event:

     #1  0x00000000004007f0 in child_function...

3. MI command (CLI-in-MI):

     frame 1

   MI event/reply:

     &"frame 1\n"
     ~"#1  0x00000000004007f9 in ..."
     =thread-selected,id="3",frame={level="1"...}
     ^done

inferior
--------

Inferior selection events only go from the console to MI, since there's
no way to select the inferior in pure MI.

1. CLI command:

     inferior 2

   MI event:

     =thread-selected,id="3"

Note that if the user selects an inferior that is not started or exited,
the MI doesn't receive a notification.  Since there is no threads to
select, the =thread-selected event does not apply...

2. MI command (CLI-in-MI):

     inferior 2

   MI event/reply:

     &"inferior 2\n"
     ~"[Switching to inferior 2 ...]"
     =thread-selected,id="4",frame={level="0"...}
     ^done

Internal implementation detail: this patch makes it possible to suppress
notifications caused by a CLI command, like what is done in mi-interp.c.
This means that it's now possible to use the
add_com_suppress_notification function to register a command with some
event suppressed.  It is used to implement the select-frame command in
this patch.

The function command_notifies_uscc_observer was added to extract
the rather complicated logical expression from the if statement.  It is
also now clearer what that logic does: if the command used by the user
already notifies the user_selected_context_changed observer, there is
not need to notify it again.  It therefore protects again emitting the
event twice.

No regressions, tested on ubuntu 14.04 x86 with target boards unix and
native-extended-gdbserver.

gdb/ChangeLog:

YYYY-MM-DD  Antoine Tremblay  <antoine.tremblay@ericsson.com>
YYYY-MM-DD  Simon Marchi  <simon.marchi@ericsson.com>

	PR gdb/20487
	* NEWS: Mention new frame field of =thread-selected event.
	* cli/cli-decode.c (add_cmd): Initialize c->suppress_notification.
	(add_com_suppress_notification): New function definition.
	(cmd_func): Set and restore the suppress_notification flag.
	* cli/cli-deicode.h (struct cmd_list_element)
	<suppress_notification>: New field.
	* cli/cli-interp.c (cli_suppress_notification): New global variable.
	(cli_on_user_selected_context_changed): New function.
	(_initialize_cli_interp): Attach to user_selected_context_changed
	observer.
	* command.h (struct cli_suppress_notification): New structure.
	(cli_suppress_notification): New global variable declaration.
	(add_com_suppress_notification): New function declaration.
	* defs.h (enum user_selected_what_flag): New enum.
	(user_selected_what): New enum flag type.
	* frame.h (print_stack_frame_to_uiout): New function declaration.
	* gdbthread.h (print_selected_thread_frame): New function declaration.
	* inferior.c (print_selected_inferior): New function definition.
	(inferior_command): Remove printing of inferior/thread/frame switch
	notifications, notify user_selected_context_changed observer.
	* inferior.h (print_selected_inferior): New function declaration.
	* mi/mi-cmds.c (struct mi_cmd): Add user_selected_context
	suppression to stack-select-frame and thread-select commands.
	* mi/mi-interp.c (struct mi_suppress_notification)
	<user_selected_context>: Initialize.
	(mi_user_selected_context_changed): New function definition.
	(_initialize_mi_interp): Attach to user_selected_context_changed.
	* mi/mi-main.c (mi_cmd_thread_select): Print thread selection reply.
	(mi_execute_command): Handle notification suppression.  Notify
	user_selected_context_changed observer on thread change instead of printing
	event directly.  Don't send it if command already sends the notification.
	(command_notifies_uscc_observer): New function.
	(mi_cmd_execute): Don't handle notification suppression.
	* mi/mi-main.h (struct mi_suppress_notification)
	<user_selected_context>: New field.
	* stack.c (print_stack_frame_to_uiout): New function definition.
	(select_frame_command): Notify user_selected_context_changed
	observer.
	(frame_command): Call print_selected_thread_frame if there's no frame
	change or notify user_selected_context_changed observer if there is.
	(up_command): Notify user_selected_context_changed observer.
	(down_command): Likewise.
	(_initialize_stack): Suppress user_selected_context notification for
	command select-frame.
	* thread.c (thread_command): Notify
	user_selected_context_changed if the thread has changed, print
	thread info directly if it hasn't.
	(do_captured_thread_select): Do not print thread switch event.
	(print_selected_thread_frame): New function definition.
	* tui/tui-interp.c (tui_on_user_selected_context_changed):
	New function definition.
	(_initialize_tui_interp): Attach to user_selected_context_changed
	observer.

gdb/doc/ChangeLog:

	PR gdb/20487
	* gdb.texinfo (Context management): Update mention of frame
	change notifications.
	(gdb/mi Async Records): Document frame field in
	=thread-select event.
	* observer.texi (GDB Observers): New user_selected_context_changed
	observer.

gdb/testsuite/ChangeLog:

	PR gdb/20487
	* gdb.mi/mi-pthreads.exp (check_mi_thread_command_set): Adapt
	=thread-select-event check.
2016-10-03 16:54:58 -04:00

360 lines
8.1 KiB
C

/* TUI Interpreter definitions for GDB, the GNU debugger.
Copyright (C) 2003-2016 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 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "cli/cli-interp.h"
#include "interps.h"
#include "top.h"
#include "event-top.h"
#include "event-loop.h"
#include "ui-out.h"
#include "cli-out.h"
#include "tui/tui-data.h"
#include "readline/readline.h"
#include "tui/tui-win.h"
#include "tui/tui.h"
#include "tui/tui-io.h"
#include "infrun.h"
#include "observer.h"
#include "gdbthread.h"
static struct ui_out *tui_ui_out (struct interp *self);
/* Set to 1 when the TUI mode must be activated when we first start
gdb. */
static int tui_start_enabled = 0;
/* Returns the INTERP if the INTERP is a TUI, and returns NULL
otherwise. */
static struct interp *
as_tui_interp (struct interp *interp)
{
if (strcmp (interp_name (interp), INTERP_TUI) == 0)
return interp;
return NULL;
}
/* Cleanup the tui before exiting. */
static void
tui_exit (void)
{
/* Disable the tui. Curses mode is left leaving the screen in a
clean state (see endwin()). */
tui_disable ();
}
/* Observers for several run control events. If the interpreter is
quiet (i.e., another interpreter is being run with
interpreter-exec), print nothing. */
/* Observer for the normal_stop notification. */
static void
tui_on_normal_stop (struct bpstats *bs, int print_frame)
{
struct switch_thru_all_uis state;
if (!print_frame)
return;
SWITCH_THRU_ALL_UIS (state)
{
struct interp *interp = top_level_interpreter ();
struct interp *tui = as_tui_interp (interp);
struct thread_info *thread;
if (tui == NULL)
continue;
thread = inferior_thread ();
if (should_print_stop_to_console (interp, thread))
print_stop_event (tui_ui_out (tui));
}
}
/* Observer for the signal_received notification. */
static void
tui_on_signal_received (enum gdb_signal siggnal)
{
struct switch_thru_all_uis state;
SWITCH_THRU_ALL_UIS (state)
{
struct interp *tui = as_tui_interp (top_level_interpreter ());
if (tui == NULL)
continue;
print_signal_received_reason (tui_ui_out (tui), siggnal);
}
}
/* Observer for the end_stepping_range notification. */
static void
tui_on_end_stepping_range (void)
{
struct switch_thru_all_uis state;
SWITCH_THRU_ALL_UIS (state)
{
struct interp *tui = as_tui_interp (top_level_interpreter ());
if (tui == NULL)
continue;
print_end_stepping_range_reason (tui_ui_out (tui));
}
}
/* Observer for the signal_exited notification. */
static void
tui_on_signal_exited (enum gdb_signal siggnal)
{
struct switch_thru_all_uis state;
SWITCH_THRU_ALL_UIS (state)
{
struct interp *tui = as_tui_interp (top_level_interpreter ());
if (tui == NULL)
continue;
print_signal_exited_reason (tui_ui_out (tui), siggnal);
}
}
/* Observer for the exited notification. */
static void
tui_on_exited (int exitstatus)
{
struct switch_thru_all_uis state;
SWITCH_THRU_ALL_UIS (state)
{
struct interp *tui = as_tui_interp (top_level_interpreter ());
if (tui == NULL)
continue;
print_exited_reason (tui_ui_out (tui), exitstatus);
}
}
/* Observer for the no_history notification. */
static void
tui_on_no_history (void)
{
struct switch_thru_all_uis state;
SWITCH_THRU_ALL_UIS (state)
{
struct interp *tui = as_tui_interp (top_level_interpreter ());
if (tui == NULL)
continue;
print_no_history_reason (tui_ui_out (tui));
}
}
/* Observer for the sync_execution_done notification. */
static void
tui_on_sync_execution_done (void)
{
struct interp *tui = as_tui_interp (top_level_interpreter ());
if (tui == NULL)
return;
display_gdb_prompt (NULL);
}
/* Observer for the command_error notification. */
static void
tui_on_command_error (void)
{
struct interp *tui = as_tui_interp (top_level_interpreter ());
if (tui == NULL)
return;
display_gdb_prompt (NULL);
}
/* Observer for the user_selected_context_changed notification. */
static void
tui_on_user_selected_context_changed (user_selected_what selection)
{
struct switch_thru_all_uis state;
struct thread_info *tp;
/* This event is suppressed. */
if (cli_suppress_notification.user_selected_context)
return;
tp = find_thread_ptid (inferior_ptid);
SWITCH_THRU_ALL_UIS (state)
{
struct interp *tui = as_tui_interp (top_level_interpreter ());
if (tui == NULL)
continue;
if (selection & USER_SELECTED_INFERIOR)
print_selected_inferior (tui_ui_out (tui));
if (tp != NULL
&& ((selection & (USER_SELECTED_THREAD | USER_SELECTED_FRAME))))
print_selected_thread_frame (tui_ui_out (tui), selection);
}
}
/* These implement the TUI interpreter. */
static void *
tui_init (struct interp *self, int top_level)
{
/* Install exit handler to leave the screen in a good shape. */
atexit (tui_exit);
tui_initialize_static_data ();
tui_initialize_io ();
tui_initialize_win ();
if (ui_file_isatty (gdb_stdout))
tui_initialize_readline ();
return NULL;
}
static int
tui_resume (void *data)
{
struct ui *ui = current_ui;
struct ui_file *stream;
/* gdb_setup_readline will change gdb_stdout. If the TUI was
previously writing to gdb_stdout, then set it to the new
gdb_stdout afterwards. */
stream = cli_out_set_stream (tui_old_uiout, gdb_stdout);
if (stream != gdb_stdout)
{
cli_out_set_stream (tui_old_uiout, stream);
stream = NULL;
}
gdb_setup_readline (1);
ui->input_handler = command_line_handler;
if (stream != NULL)
cli_out_set_stream (tui_old_uiout, gdb_stdout);
if (tui_start_enabled)
tui_enable ();
return 1;
}
static int
tui_suspend (void *data)
{
tui_start_enabled = tui_active;
tui_disable ();
return 1;
}
static struct ui_out *
tui_ui_out (struct interp *self)
{
if (tui_active)
return tui_out;
else
return tui_old_uiout;
}
static struct gdb_exception
tui_exec (void *data, const char *command_str)
{
internal_error (__FILE__, __LINE__, _("tui_exec called"));
}
/* The TUI interpreter's vtable. */
static const struct interp_procs tui_interp_procs = {
tui_init,
tui_resume,
tui_suspend,
tui_exec,
tui_ui_out,
NULL,
cli_interpreter_pre_command_loop,
cli_interpreter_supports_command_editing,
};
/* Factory for TUI interpreters. */
static struct interp *
tui_interp_factory (const char *name)
{
return interp_new (name, &tui_interp_procs, NULL);
}
/* Provide a prototype to silence -Wmissing-prototypes. */
extern initialize_file_ftype _initialize_tui_interp;
void
_initialize_tui_interp (void)
{
interp_factory_register (INTERP_TUI, tui_interp_factory);
if (interpreter_p && strcmp (interpreter_p, INTERP_TUI) == 0)
tui_start_enabled = 1;
if (interpreter_p && strcmp (interpreter_p, INTERP_CONSOLE) == 0)
{
xfree (interpreter_p);
interpreter_p = xstrdup (INTERP_TUI);
}
/* If changing this, remember to update cli-interp.c as well. */
observer_attach_normal_stop (tui_on_normal_stop);
observer_attach_signal_received (tui_on_signal_received);
observer_attach_end_stepping_range (tui_on_end_stepping_range);
observer_attach_signal_exited (tui_on_signal_exited);
observer_attach_exited (tui_on_exited);
observer_attach_no_history (tui_on_no_history);
observer_attach_sync_execution_done (tui_on_sync_execution_done);
observer_attach_command_error (tui_on_command_error);
observer_attach_user_selected_context_changed
(tui_on_user_selected_context_changed);
}