binutils-gdb/gdb/command.h
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

427 lines
15 KiB
C

/* Header file for command creation.
Copyright (C) 1986-2016 Free Software Foundation, Inc.
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/>. */
#if !defined (COMMAND_H)
#define COMMAND_H 1
#include "gdb_vecs.h"
/* This file defines the public interface for any code wanting to
create commands. */
/* Command classes are top-level categories into which commands are
broken down for "help" purposes.
Notes on classes: class_alias is for alias commands which are not
abbreviations of the original command. class-pseudo is for
commands which are not really commands nor help topics ("stop"). */
enum command_class
{
/* Special args to help_list */
class_deprecated = -3, all_classes = -2, all_commands = -1,
/* Classes of commands */
no_class = -1, class_run = 0, class_vars, class_stack, class_files,
class_support, class_info, class_breakpoint, class_trace,
class_alias, class_bookmark, class_obscure, class_maintenance,
class_pseudo, class_tui, class_user, class_xdb,
no_set_class /* Used for "show" commands that have no corresponding
"set" command. */
};
/* FIXME: cagney/2002-03-17: Once cmd_type() has been removed, ``enum
cmd_types'' can be moved from "command.h" to "cli-decode.h". */
/* Not a set/show command. Note that some commands which begin with
"set" or "show" might be in this category, if their syntax does
not fall into one of the following categories. */
typedef enum cmd_types
{
not_set_cmd,
set_cmd,
show_cmd
}
cmd_types;
/* Types of "set" or "show" command. */
typedef enum var_types
{
/* "on" or "off". *VAR is an integer which is nonzero for on,
zero for off. */
var_boolean,
/* "on" / "true" / "enable" or "off" / "false" / "disable" or
"auto. *VAR is an ``enum auto_boolean''. NOTE: In general a
custom show command will need to be implemented - one that for
"auto" prints both the "auto" and the current auto-selected
value. */
var_auto_boolean,
/* Unsigned Integer. *VAR is an unsigned int. The user can type
0 to mean "unlimited", which is stored in *VAR as UINT_MAX. */
var_uinteger,
/* Like var_uinteger but signed. *VAR is an int. The user can
type 0 to mean "unlimited", which is stored in *VAR as
INT_MAX. The only remaining use of it is the Python API.
Don't use it elsewhere. */
var_integer,
/* String which the user enters with escapes (e.g. the user types
\n and it is a real newline in the stored string).
*VAR is a malloc'd string, or NULL if the string is empty. */
var_string,
/* String which stores what the user types verbatim.
*VAR is a malloc'd string, or NULL if the string is empty. */
var_string_noescape,
/* String which stores a filename. (*VAR) is a malloc'd string,
or "" if the string was empty. */
var_optional_filename,
/* String which stores a filename. (*VAR) is a malloc'd
string. */
var_filename,
/* ZeroableInteger. *VAR is an int. Like var_integer except
that zero really means zero. */
var_zinteger,
/* ZeroableUnsignedInteger. *VAR is an unsigned int. Zero really
means zero. */
var_zuinteger,
/* ZeroableUnsignedInteger with unlimited value. *VAR is an int,
but its range is [0, INT_MAX]. -1 stands for unlimited and
other negative numbers are not allowed. */
var_zuinteger_unlimited,
/* Enumerated type. Can only have one of the specified values.
*VAR is a char pointer to the name of the element that we
find. */
var_enum
}
var_types;
/* This structure records one command'd definition. */
struct cmd_list_element;
typedef void cmd_cfunc_ftype (char *args, int from_tty);
/* This structure specifies notifications to be suppressed by a cli
command interpreter. */
struct cli_suppress_notification
{
/* Inferior, thread, frame selected notification suppressed? */
int user_selected_context;
};
extern struct cli_suppress_notification cli_suppress_notification;
/* Forward-declarations of the entry-points of cli/cli-decode.c. */
/* API to the manipulation of command lists. */
extern int valid_user_defined_cmd_name_p (const char *name);
extern struct cmd_list_element *add_cmd (const char *, enum command_class,
cmd_cfunc_ftype *fun,
const char *,
struct cmd_list_element **);
extern struct cmd_list_element *add_alias_cmd (const char *, const char *,
enum command_class, int,
struct cmd_list_element **);
extern struct cmd_list_element *add_prefix_cmd (const char *, enum command_class,
cmd_cfunc_ftype *fun,
const char *,
struct cmd_list_element **,
const char *, int,
struct cmd_list_element **);
extern struct cmd_list_element *add_abbrev_prefix_cmd (const char *,
enum command_class,
cmd_cfunc_ftype *fun,
const char *,
struct cmd_list_element
**, const char *, int,
struct cmd_list_element
**);
/* Set the commands corresponding callback. */
extern void set_cmd_cfunc (struct cmd_list_element *cmd,
cmd_cfunc_ftype *cfunc);
typedef void cmd_sfunc_ftype (char *args, int from_tty,
struct cmd_list_element *c);
extern void set_cmd_sfunc (struct cmd_list_element *cmd,
cmd_sfunc_ftype *sfunc);
typedef VEC (char_ptr) *completer_ftype (struct cmd_list_element *,
const char *, const char *);
typedef void completer_ftype_void (struct cmd_list_element *,
const char *, const char *);
extern void set_cmd_completer (struct cmd_list_element *, completer_ftype *);
/* Set the completer_handle_brkchars callback. */
extern void set_cmd_completer_handle_brkchars (struct cmd_list_element *,
completer_ftype_void *);
/* HACK: cagney/2002-02-23: Code, mostly in tracepoints.c, grubs
around in cmd objects to test the value of the commands sfunc(). */
extern int cmd_cfunc_eq (struct cmd_list_element *cmd,
cmd_cfunc_ftype *cfun);
/* Each command object has a local context attached to it. */
extern void set_cmd_context (struct cmd_list_element *cmd,
void *context);
extern void *get_cmd_context (struct cmd_list_element *cmd);
/* Execute CMD's pre/post hook. Throw an error if the command fails.
If already executing this pre/post hook, or there is no pre/post
hook, the call is silently ignored. */
extern void execute_cmd_pre_hook (struct cmd_list_element *cmd);
extern void execute_cmd_post_hook (struct cmd_list_element *cmd);
/* Return the type of the command. */
extern enum cmd_types cmd_type (struct cmd_list_element *cmd);
/* Flag for an ambiguous cmd_list result. */
#define CMD_LIST_AMBIGUOUS ((struct cmd_list_element *) -1)
extern struct cmd_list_element *lookup_cmd (const char **,
struct cmd_list_element *, char *,
int, int);
extern struct cmd_list_element *lookup_cmd_1 (const char **,
struct cmd_list_element *,
struct cmd_list_element **,
int);
extern struct cmd_list_element *deprecate_cmd (struct cmd_list_element *,
const char * );
extern void deprecated_cmd_warning (const char *);
extern int lookup_cmd_composition (const char *text,
struct cmd_list_element **alias,
struct cmd_list_element **prefix_cmd,
struct cmd_list_element **cmd);
extern struct cmd_list_element *add_com (const char *, enum command_class,
cmd_cfunc_ftype *fun,
const char *);
extern struct cmd_list_element *add_com_alias (const char *, const char *,
enum command_class, int);
extern struct cmd_list_element *add_com_suppress_notification
(const char *name, enum command_class theclass,
cmd_cfunc_ftype *fun, const char *doc,
int *supress_notification);
extern struct cmd_list_element *add_info (const char *,
cmd_cfunc_ftype *fun,
const char *);
extern struct cmd_list_element *add_info_alias (const char *, const char *,
int);
extern VEC (char_ptr) *complete_on_cmdlist (struct cmd_list_element *,
const char *, const char *, int);
extern VEC (char_ptr) *complete_on_enum (const char *const *enumlist,
const char *, const char *);
/* Functions that implement commands about CLI commands. */
extern void help_list (struct cmd_list_element *, const char *,
enum command_class, struct ui_file *);
/* Method for show a set/show variable's VALUE on FILE. If this
method isn't supplied deprecated_show_value_hack() is called (which
is not good). */
typedef void (show_value_ftype) (struct ui_file *file,
int from_tty,
struct cmd_list_element *cmd,
const char *value);
/* NOTE: i18n: This function is not i18n friendly. Callers should
instead print the value out directly. */
extern show_value_ftype deprecated_show_value_hack;
extern void add_setshow_enum_cmd (const char *name,
enum command_class theclass,
const char *const *enumlist,
const char **var,
const char *set_doc,
const char *show_doc,
const char *help_doc,
cmd_sfunc_ftype *set_func,
show_value_ftype *show_func,
struct cmd_list_element **set_list,
struct cmd_list_element **show_list);
extern void add_setshow_auto_boolean_cmd (const char *name,
enum command_class theclass,
enum auto_boolean *var,
const char *set_doc,
const char *show_doc,
const char *help_doc,
cmd_sfunc_ftype *set_func,
show_value_ftype *show_func,
struct cmd_list_element **set_list,
struct cmd_list_element **show_list);
extern void add_setshow_boolean_cmd (const char *name,
enum command_class theclass,
int *var,
const char *set_doc, const char *show_doc,
const char *help_doc,
cmd_sfunc_ftype *set_func,
show_value_ftype *show_func,
struct cmd_list_element **set_list,
struct cmd_list_element **show_list);
extern void add_setshow_filename_cmd (const char *name,
enum command_class theclass,
char **var,
const char *set_doc,
const char *show_doc,
const char *help_doc,
cmd_sfunc_ftype *set_func,
show_value_ftype *show_func,
struct cmd_list_element **set_list,
struct cmd_list_element **show_list);
extern void add_setshow_string_cmd (const char *name,
enum command_class theclass,
char **var,
const char *set_doc,
const char *show_doc,
const char *help_doc,
cmd_sfunc_ftype *set_func,
show_value_ftype *show_func,
struct cmd_list_element **set_list,
struct cmd_list_element **show_list);
extern struct cmd_list_element *add_setshow_string_noescape_cmd
(const char *name,
enum command_class theclass,
char **var,
const char *set_doc,
const char *show_doc,
const char *help_doc,
cmd_sfunc_ftype *set_func,
show_value_ftype *show_func,
struct cmd_list_element **set_list,
struct cmd_list_element **show_list);
extern void add_setshow_optional_filename_cmd (const char *name,
enum command_class theclass,
char **var,
const char *set_doc,
const char *show_doc,
const char *help_doc,
cmd_sfunc_ftype *set_func,
show_value_ftype *show_func,
struct cmd_list_element **set_list,
struct cmd_list_element **show_list);
extern void add_setshow_integer_cmd (const char *name,
enum command_class theclass,
int *var,
const char *set_doc,
const char *show_doc,
const char *help_doc,
cmd_sfunc_ftype *set_func,
show_value_ftype *show_func,
struct cmd_list_element **set_list,
struct cmd_list_element **show_list);
extern void add_setshow_uinteger_cmd (const char *name,
enum command_class theclass,
unsigned int *var,
const char *set_doc,
const char *show_doc,
const char *help_doc,
cmd_sfunc_ftype *set_func,
show_value_ftype *show_func,
struct cmd_list_element **set_list,
struct cmd_list_element **show_list);
extern void add_setshow_zinteger_cmd (const char *name,
enum command_class theclass,
int *var,
const char *set_doc,
const char *show_doc,
const char *help_doc,
cmd_sfunc_ftype *set_func,
show_value_ftype *show_func,
struct cmd_list_element **set_list,
struct cmd_list_element **show_list);
extern void add_setshow_zuinteger_cmd (const char *name,
enum command_class theclass,
unsigned int *var,
const char *set_doc,
const char *show_doc,
const char *help_doc,
cmd_sfunc_ftype *set_func,
show_value_ftype *show_func,
struct cmd_list_element **set_list,
struct cmd_list_element **show_list);
extern void
add_setshow_zuinteger_unlimited_cmd (const char *name,
enum command_class theclass,
int *var,
const char *set_doc,
const char *show_doc,
const char *help_doc,
cmd_sfunc_ftype *set_func,
show_value_ftype *show_func,
struct cmd_list_element **set_list,
struct cmd_list_element **show_list);
/* Do a "show" command for each thing on a command list. */
extern void cmd_show_list (struct cmd_list_element *, int, const char *);
/* Used everywhere whenever at least one parameter is required and
none is specified. */
extern void error_no_arg (const char *) ATTRIBUTE_NORETURN;
extern void dont_repeat (void);
extern struct cleanup *prevent_dont_repeat (void);
/* Used to mark commands that don't do anything. If we just leave the
function field NULL, the command is interpreted as a help topic, or
as a class of commands. */
extern void not_just_help_class_command (char *, int);
/* Check function pointer. */
extern int cmd_func_p (struct cmd_list_element *cmd);
/* Call the command function. */
extern void cmd_func (struct cmd_list_element *cmd,
char *args, int from_tty);
#endif /* !defined (COMMAND_H) */