binutils-gdb/gdb/cli/cli-interp.c
Pedro Alves 92bcb5f949 Make display_gdb_prompt CLI-only.
Enabling target-async by default will require implementing sync
execution on top of an async target, much like foreground command are
implemented on the CLI in async mode.

In order to do that, we will need better control of when to print the
MI prompt.  Currently the interp->display_prompt_p hook is all we
have, and MI just always returns false, meaning, make
display_gdb_prompt a no-op.  We'll need to be able to know to print
the MI prompt in some of the conditions that display_gdb_prompt is
called from the core, but not all.

This is all a litte twisted currently.  As we can see,
display_gdb_prompt is really CLI specific, so make the console
interpreters (console/tui) themselves call it.  To be able to do that,
and add a few different observers that the interpreters can use to
distinguish when or why the the prompt is being printed:

#1 - one called whenever a command is cancelled due to an error.
#2 - another for when a foreground command just finished.

In both cases, CLI wants to print the prompt, while MI doesn't.

MI will want to print the prompt in the second case when in a special
MI mode.

The display_gdb_prompt call in interp_set made me pause.  The comment
there reads:

  /* Finally, put up the new prompt to show that we are indeed here.
     Also, display_gdb_prompt for the console does some readline magic
     which is needed for the console interpreter, at least...  */

But, that looks very much like a no-op to me currently:

 - the MI interpreter always return false in the prompt hook, meaning
   actually display no prompt.

 - the interpreter used at that point is still quiet.  And the
   console/tui interpreters return false in the prompt hook if they're
   quiet, meaning actually display no prompt.

The only remaining possible use would then be the readline magic.  But
whatever that might have been, it's not reacheable today either,
because display_gdb_prompt returns early, before touching readline if
the interpreter returns false in the display_prompt_p hook.

Tested on x86_64 Fedora 20, sync and async modes.

gdb/
2014-05-29  Pedro Alves  <palves@redhat.com>

	* cli/cli-interp.c (cli_interpreter_display_prompt_p): Delete.
	(_initialize_cli_interp): Adjust.
	* event-loop.c: Include "observer.h".
	(start_event_loop): Notify 'command_error' observers instead of
	calling display_gdb_prompt.  Remove FIXME comment.
	* event-top.c (display_gdb_prompt): Remove call into the
	interpreters.
	* inf-loop.c: Include "observer.h".
	(inferior_event_handler): Notify 'command_error' observers instead
	of calling display_gdb_prompt.
	* infrun.c (fetch_inferior_event): Notify 'sync_execution_done'
	observers instead of calling display_gdb_prompt.
	* interps.c (interp_set): Don't call display_gdb_prompt.
	(current_interp_display_prompt_p): Delete.
	* interps.h (interp_prompt_p): Delete declaration.
	(interp_prompt_p_ftype): Delete.
	(struct interp_procs) <prompt_proc_p>: Delete field.
	(current_interp_display_prompt_p): Delete declaration.
	* mi-interp.c (mi_interpreter_prompt_p): Delete.
	(_initialize_mi_interp): Adjust.
	* tui-interp.c (tui_init): Install 'sync_execution_done' and
	'command_error' observers.
	(tui_on_sync_execution_done, tui_on_command_error): New
	functions.
	(tui_display_prompt_p): Delete.
	(_initialize_tui_interp): Adjust.

gdb/doc/
2014-05-29  Pedro Alves  <palves@redhat.com>

	* observer.texi (sync_execution_done, command_error): New
	subjects.
2014-05-29 13:47:09 +01:00

233 lines
6.1 KiB
C

/* CLI Definitions for GDB, the GNU debugger.
Copyright (C) 2002-2014 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 "interps.h"
#include "event-top.h"
#include "ui-out.h"
#include "cli-out.h"
#include "top.h" /* for "execute_command" */
#include <string.h>
#include "exceptions.h"
#include "infrun.h"
#include "observer.h"
/* These are the ui_out and the interpreter for the console
interpreter. */
struct ui_out *cli_uiout;
static struct interp *cli_interp;
/* Longjmp-safe wrapper for "execute_command". */
static struct gdb_exception safe_execute_command (struct ui_out *uiout,
char *command,
int from_tty);
/* 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 signal_received notification. */
static void
cli_on_signal_received (enum gdb_signal siggnal)
{
if (!interp_quiet_p (cli_interp))
print_signal_received_reason (cli_uiout, siggnal);
}
/* Observer for the end_stepping_range notification. */
static void
cli_on_end_stepping_range (void)
{
if (!interp_quiet_p (cli_interp))
print_end_stepping_range_reason (cli_uiout);
}
/* Observer for the signalled notification. */
static void
cli_on_signal_exited (enum gdb_signal siggnal)
{
if (!interp_quiet_p (cli_interp))
print_signal_exited_reason (cli_uiout, siggnal);
}
/* Observer for the exited notification. */
static void
cli_on_exited (int exitstatus)
{
if (!interp_quiet_p (cli_interp))
print_exited_reason (cli_uiout, exitstatus);
}
/* Observer for the no_history notification. */
static void
cli_on_no_history (void)
{
if (!interp_quiet_p (cli_interp))
print_no_history_reason (cli_uiout);
}
/* Observer for the sync_execution_done notification. */
static void
cli_on_sync_execution_done (void)
{
if (!interp_quiet_p (cli_interp))
display_gdb_prompt (NULL);
}
/* Observer for the command_error notification. */
static void
cli_on_command_error (void)
{
if (!interp_quiet_p (cli_interp))
display_gdb_prompt (NULL);
}
/* These implement the cli out interpreter: */
static void *
cli_interpreter_init (struct interp *self, int top_level)
{
/* If changing this, remember to update tui-interp.c as well. */
observer_attach_end_stepping_range (cli_on_end_stepping_range);
observer_attach_signal_received (cli_on_signal_received);
observer_attach_signal_exited (cli_on_signal_exited);
observer_attach_exited (cli_on_exited);
observer_attach_no_history (cli_on_no_history);
observer_attach_sync_execution_done (cli_on_sync_execution_done);
observer_attach_command_error (cli_on_command_error);
return NULL;
}
static int
cli_interpreter_resume (void *data)
{
struct ui_file *stream;
/*sync_execution = 1; */
/* gdb_setup_readline will change gdb_stdout. If the CLI was
previously writing to gdb_stdout, then set it to the new
gdb_stdout afterwards. */
stream = cli_out_set_stream (cli_uiout, gdb_stdout);
if (stream != gdb_stdout)
{
cli_out_set_stream (cli_uiout, stream);
stream = NULL;
}
gdb_setup_readline ();
if (stream != NULL)
cli_out_set_stream (cli_uiout, gdb_stdout);
return 1;
}
static int
cli_interpreter_suspend (void *data)
{
gdb_disable_readline ();
return 1;
}
static struct gdb_exception
cli_interpreter_exec (void *data, const char *command_str)
{
struct ui_file *old_stream;
struct gdb_exception result;
/* FIXME: cagney/2003-02-01: Need to const char *propogate
safe_execute_command. */
char *str = strcpy (alloca (strlen (command_str) + 1), command_str);
/* gdb_stdout could change between the time cli_uiout was
initialized and now. Since we're probably using a different
interpreter which has a new ui_file for gdb_stdout, use that one
instead of the default.
It is important that it gets reset everytime, since the user
could set gdb to use a different interpreter. */
old_stream = cli_out_set_stream (cli_uiout, gdb_stdout);
result = safe_execute_command (cli_uiout, str, 1);
cli_out_set_stream (cli_uiout, old_stream);
return result;
}
static struct gdb_exception
safe_execute_command (struct ui_out *command_uiout, char *command, int from_tty)
{
volatile struct gdb_exception e;
struct ui_out *saved_uiout;
/* Save and override the global ``struct ui_out'' builder. */
saved_uiout = current_uiout;
current_uiout = command_uiout;
TRY_CATCH (e, RETURN_MASK_ALL)
{
execute_command (command, from_tty);
}
/* Restore the global builder. */
current_uiout = saved_uiout;
/* FIXME: cagney/2005-01-13: This shouldn't be needed. Instead the
caller should print the exception. */
exception_print (gdb_stderr, e);
return e;
}
static struct ui_out *
cli_ui_out (struct interp *self)
{
return cli_uiout;
}
/* Standard gdb initialization hook. */
extern initialize_file_ftype _initialize_cli_interp; /* -Wmissing-prototypes */
void
_initialize_cli_interp (void)
{
static const struct interp_procs procs = {
cli_interpreter_init, /* init_proc */
cli_interpreter_resume, /* resume_proc */
cli_interpreter_suspend, /* suspend_proc */
cli_interpreter_exec, /* exec_proc */
cli_ui_out, /* ui_out_proc */
NULL, /* set_logging_proc */
cli_command_loop /* command_loop_proc */
};
/* Create a default uiout builder for the CLI. */
cli_uiout = cli_out_new (gdb_stdout);
cli_interp = interp_new (INTERP_CONSOLE, &procs);
interp_add (cli_interp);
}