binutils-gdb/gdb/interps.h
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

119 lines
4.4 KiB
C

/* Manages interpreters for GDB, the GNU debugger.
Copyright (C) 2000-2014 Free Software Foundation, Inc.
Written by Jim Ingham <jingham@apple.com> of Apple Computer, 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/>. */
#ifndef INTERPS_H
#define INTERPS_H
#include "exceptions.h"
struct ui_out;
struct interp;
extern int interp_resume (struct interp *interp);
extern int interp_suspend (struct interp *interp);
extern struct gdb_exception interp_exec (struct interp *interp,
const char *command);
extern int interp_quiet_p (struct interp *interp);
typedef void *(interp_init_ftype) (struct interp *self, int top_level);
typedef int (interp_resume_ftype) (void *data);
typedef int (interp_suspend_ftype) (void *data);
typedef struct gdb_exception (interp_exec_ftype) (void *data,
const char *command);
typedef void (interp_command_loop_ftype) (void *data);
typedef struct ui_out *(interp_ui_out_ftype) (struct interp *self);
typedef int (interp_set_logging_ftype) (struct interp *self, int start_log,
struct ui_file *out,
struct ui_file *logfile);
struct interp_procs
{
interp_init_ftype *init_proc;
interp_resume_ftype *resume_proc;
interp_suspend_ftype *suspend_proc;
interp_exec_ftype *exec_proc;
/* Returns the ui_out currently used to collect results for this
interpreter. It can be a formatter for stdout, as is the case
for the console & mi outputs, or it might be a result
formatter. */
interp_ui_out_ftype *ui_out_proc;
/* Provides a hook for interpreters to do any additional
setup/cleanup that they might need when logging is enabled or
disabled. */
interp_set_logging_ftype *set_logging_proc;
interp_command_loop_ftype *command_loop_proc;
};
extern struct interp *interp_new (const char *name, const struct interp_procs *procs);
extern void interp_add (struct interp *interp);
extern int interp_set (struct interp *interp, int top_level);
extern struct interp *interp_lookup (const char *name);
extern struct ui_out *interp_ui_out (struct interp *interp);
extern void *interp_data (struct interp *interp);
extern const char *interp_name (struct interp *interp);
extern struct interp *interp_set_temp (const char *name);
extern int current_interp_named_p (const char *name);
extern void current_interp_command_loop (void);
/* Call this function to give the current interpreter an opportunity
to do any special handling of streams when logging is enabled or
disabled. START_LOG is 1 when logging is starting, 0 when it ends,
and OUT is the stream for the log file; it will be NULL when
logging is ending. LOGFILE is non-NULL if the output streams
are to be tees, with the log file as one of the outputs. */
extern int current_interp_set_logging (int start_log, struct ui_file *out,
struct ui_file *logfile);
/* Returns opaque data associated with the top-level interpreter. */
extern void *top_level_interpreter_data (void);
extern struct interp *top_level_interpreter (void);
extern struct interp *command_interp (void);
/* True if the current interpreter is in async mode, false if in sync
mode. If in sync mode, running a synchronous execution command
(with execute_command, e.g, "next") will not return until the
command is finished. If in async mode, then running a synchronous
command returns right after resuming the target. Waiting for the
command's completion is later done on the top event loop (using
continuations). */
extern int interpreter_async;
extern void clear_interpreter_hooks (void);
/* well-known interpreters */
#define INTERP_CONSOLE "console"
#define INTERP_MI1 "mi1"
#define INTERP_MI2 "mi2"
#define INTERP_MI3 "mi3"
#define INTERP_MI "mi"
#define INTERP_TUI "tui"
#define INTERP_INSIGHT "insight"
#endif