binutils-gdb/gdb/tui/tui-interp.c
Tom Tromey a350efd4fb Fix crash when exiting TUI with gdb -tui
PR tui/25348 points out that, when "gdb -tui" is used, then exiting
the TUI will cause a crash.

This happens because tui_setup_io stashes some readline variables --
but because this happens before readline is initialized, some of these
are NULL.  Then, when exiting the TUI, the NULL values are "restored",
causing a crash in readline.

This patch fixes the problem by ensuring that readline is initialized
first.  Back in commit 11061048d ("Give a name to the TUI SingleKey
keymap"), a call to rl_initialize was removed from
tui_initialize_readline; this patch resurrects the call, but moves it
to the end of the function, so as not to remove the ability to modify
the SingleKey map from .inputrc.

gdb/ChangeLog
2020-06-16  Tom Tromey  <tom@tromey.com>

	PR tui/25348:
	* tui/tui.c (tui_ensure_readline_initialized): Rename from
	tui_initialize_readline.  Only run once.  Call rl_initialize.
	* tui/tui.h (tui_ensure_readline_initialized): Rename from
	tui_initialize_readline.
	* tui/tui-io.c (tui_setup_io): Call
	tui_ensure_readline_initialized.
	* tui/tui-interp.c (tui_interp::init): Update.
2020-06-16 18:02:20 -06:00

336 lines
7.6 KiB
C

/* TUI Interpreter definitions for GDB, the GNU debugger.
Copyright (C) 2003-2020 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 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 "gdbsupport/event-loop.h"
#include "ui-out.h"
#include "cli-out.h"
#include "tui/tui-data.h"
#include "tui/tui-win.h"
#include "tui/tui.h"
#include "tui/tui-io.h"
#include "infrun.h"
#include "observable.h"
#include "gdbthread.h"
#include "inferior.h"
#include "main.h"
/* Set to true when the TUI mode must be activated when we first start
gdb. */
static bool tui_start_enabled = false;
class tui_interp final : public cli_interp_base
{
public:
explicit tui_interp (const char *name)
: cli_interp_base (name)
{}
void init (bool top_level) override;
void resume () override;
void suspend () override;
gdb_exception exec (const char *command_str) override;
ui_out *interp_ui_out () override;
};
/* Returns the INTERP if the INTERP is a TUI, and returns NULL
otherwise. */
static tui_interp *
as_tui_interp (struct interp *interp)
{
return dynamic_cast<tui_interp *> (interp);
}
/* 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)
{
if (!print_frame)
return;
SWITCH_THRU_ALL_UIS ()
{
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->interp_ui_out ());
}
}
/* Observer for the signal_received notification. */
static void
tui_on_signal_received (enum gdb_signal siggnal)
{
SWITCH_THRU_ALL_UIS ()
{
struct interp *tui = as_tui_interp (top_level_interpreter ());
if (tui == NULL)
continue;
print_signal_received_reason (tui->interp_ui_out (), siggnal);
}
}
/* Observer for the end_stepping_range notification. */
static void
tui_on_end_stepping_range (void)
{
SWITCH_THRU_ALL_UIS ()
{
struct interp *tui = as_tui_interp (top_level_interpreter ());
if (tui == NULL)
continue;
print_end_stepping_range_reason (tui->interp_ui_out ());
}
}
/* Observer for the signal_exited notification. */
static void
tui_on_signal_exited (enum gdb_signal siggnal)
{
SWITCH_THRU_ALL_UIS ()
{
struct interp *tui = as_tui_interp (top_level_interpreter ());
if (tui == NULL)
continue;
print_signal_exited_reason (tui->interp_ui_out (), siggnal);
}
}
/* Observer for the exited notification. */
static void
tui_on_exited (int exitstatus)
{
SWITCH_THRU_ALL_UIS ()
{
struct interp *tui = as_tui_interp (top_level_interpreter ());
if (tui == NULL)
continue;
print_exited_reason (tui->interp_ui_out (), exitstatus);
}
}
/* Observer for the no_history notification. */
static void
tui_on_no_history (void)
{
SWITCH_THRU_ALL_UIS ()
{
struct interp *tui = as_tui_interp (top_level_interpreter ());
if (tui == NULL)
continue;
print_no_history_reason (tui->interp_ui_out ());
}
}
/* 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)
{
/* This event is suppressed. */
if (cli_suppress_notification.user_selected_context)
return;
thread_info *tp = inferior_ptid != null_ptid ? inferior_thread () : NULL;
SWITCH_THRU_ALL_UIS ()
{
struct interp *tui = as_tui_interp (top_level_interpreter ());
if (tui == NULL)
continue;
if (selection & USER_SELECTED_INFERIOR)
print_selected_inferior (tui->interp_ui_out ());
if (tp != NULL
&& ((selection & (USER_SELECTED_THREAD | USER_SELECTED_FRAME))))
print_selected_thread_frame (tui->interp_ui_out (), selection);
}
}
/* These implement the TUI interpreter. */
void
tui_interp::init (bool top_level)
{
/* Install exit handler to leave the screen in a good shape. */
atexit (tui_exit);
tui_initialize_io ();
tui_initialize_win ();
if (gdb_stdout->isatty ())
tui_ensure_readline_initialized ();
}
void
tui_interp::resume ()
{
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 = tui_old_uiout->set_stream (gdb_stdout);
if (stream != gdb_stdout)
{
tui_old_uiout->set_stream (stream);
stream = NULL;
}
gdb_setup_readline (1);
ui->input_handler = command_line_handler;
if (stream != NULL)
tui_old_uiout->set_stream (gdb_stdout);
if (tui_start_enabled)
tui_enable ();
}
void
tui_interp::suspend ()
{
tui_start_enabled = tui_active;
tui_disable ();
}
ui_out *
tui_interp::interp_ui_out ()
{
if (tui_active)
return tui_out;
else
return tui_old_uiout;
}
gdb_exception
tui_interp::exec (const char *command_str)
{
internal_error (__FILE__, __LINE__, _("tui_exec called"));
}
/* Factory for TUI interpreters. */
static struct interp *
tui_interp_factory (const char *name)
{
return new tui_interp (name);
}
void _initialize_tui_interp ();
void
_initialize_tui_interp ()
{
interp_factory_register (INTERP_TUI, tui_interp_factory);
if (interpreter_p && strcmp (interpreter_p, INTERP_TUI) == 0)
tui_start_enabled = true;
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. */
gdb::observers::normal_stop.attach (tui_on_normal_stop);
gdb::observers::signal_received.attach (tui_on_signal_received);
gdb::observers::end_stepping_range.attach (tui_on_end_stepping_range);
gdb::observers::signal_exited.attach (tui_on_signal_exited);
gdb::observers::exited.attach (tui_on_exited);
gdb::observers::no_history.attach (tui_on_no_history);
gdb::observers::sync_execution_done.attach (tui_on_sync_execution_done);
gdb::observers::command_error.attach (tui_on_command_error);
gdb::observers::user_selected_context_changed.attach
(tui_on_user_selected_context_changed);
}