binutils-gdb/gdb/thread-fsm.h
Pedro Alves 388a708404 Convert infcalls to thread_fsm mechanism
This removes infcall-specific special casing from normal_stop,
simplifying it.

Like the "finish" command's, the FSM is responsible for storing the
function's return value.

gdb/ChangeLog:
2015-09-09  Pedro Alves  <palves@redhat.com>

	* infcall.c: Include thread_fsm.h.
	(struct call_return_meta_info): New.
	(get_call_return_value): New function, factored out from
	call_function_by_hand_dummy.
	(struct call_thread_fsm): New.
	(call_thread_fsm_ops): New global.
	(new_call_thread_fsm, call_thread_fsm_should_stop)
	(call_thread_fsm_should_notify_stop): New functions.
	(run_inferior_call): Add 'sm' parameter.  Associate the FSM with
	the thread.
	(call_function_by_hand_dummy): Create a new call_thread_fsm
	instance, associate it with the thread, and wait for the FSM to
	finish.  If finished successfully, fetch the function's result
	value out of the FSM.
	* infrun.c (fetch_inferior_event): If the FSM says the stop
	shouldn't be notified, don't call normal_stop.
	(maybe_remove_breakpoints): New function, factored out from ...
	(normal_stop): ... here.  Simplify.
	* infrun.h (maybe_remove_breakpoints): Declare.
	* thread-fsm.c (thread_fsm_should_notify_stop): New function.
	(thread-fsm.h) <struct thread_fsm_ops>: New field.
	(thread_fsm_should_notify_stop): Declare.
2015-09-09 18:24:34 +01:00

105 lines
3.8 KiB
C

/* Thread command's finish-state machine, for GDB, the GNU debugger.
Copyright (C) 2015 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/>. */
#ifndef THREAD_FSM_H
#define THREAD_FSM_H
#include "mi/mi-common.h" /* For enum async_reply_reason. */
struct return_value_info;
struct thread_fsm_ops;
/* A thread finite-state machine structure contains the necessary info
and callbacks to manage the state machine protocol of a thread's
execution command. */
struct thread_fsm
{
/* Pointer of the virtual table of methods. */
struct thread_fsm_ops *ops;
/* Whether the FSM is done successfully. */
int finished;
};
/* The virtual table of a thread_fsm. */
struct thread_fsm_ops
{
/* The destructor. This should simply free heap allocated data
structures. Cleaning up target resources (like, e.g.,
breakpoints) should be done in the clean_up method. */
void (*dtor) (struct thread_fsm *self);
/* Called to clean up target resources after the FSM. E.g., if the
FSM created internal breakpoints, this is where they should be
deleted. */
void (*clean_up) (struct thread_fsm *self);
/* Called after handle_inferior_event decides the target is done
(that is, after stop_waiting). The FSM is given a chance to
decide whether the command is done and thus the target should
stop, or whether there's still more to do and thus the thread
should be re-resumed. This is a good place to cache target data
too. For example, the "finish" command saves the just-finished
function's return value here. */
int (*should_stop) (struct thread_fsm *self);
/* If this FSM saved a function's return value, you can use this
method to retrieve it. Otherwise, this returns NULL. */
struct return_value_info *(*return_value) (struct thread_fsm *self);
/* The async_reply_reason that is broadcast to MI clients if this
FSM finishes successfully. */
enum async_reply_reason (*async_reply_reason) (struct thread_fsm *self);
/* Whether the stop should be notified to the user/frontend. */
int (*should_notify_stop) (struct thread_fsm *self);
};
/* Initialize FSM. */
extern void thread_fsm_ctor (struct thread_fsm *fsm,
struct thread_fsm_ops *ops);
/* Calls the FSM's dtor method, and then frees FSM. */
extern void thread_fsm_delete (struct thread_fsm *fsm);
/* Calls the FSM's clean_up method. */
extern void thread_fsm_clean_up (struct thread_fsm *fsm);
/* Calls the FSM's should_stop method. */
extern int thread_fsm_should_stop (struct thread_fsm *fsm);
/* Calls the FSM's return_value method. */
extern struct return_value_info *
thread_fsm_return_value (struct thread_fsm *fsm);
/* Marks the FSM as completed successfully. */
extern void thread_fsm_set_finished (struct thread_fsm *fsm);
/* Returns true if the FSM completed successfully. */
extern int thread_fsm_finished_p (struct thread_fsm *fsm);
/* Calls the FSM's reply_reason method. */
extern enum async_reply_reason
thread_fsm_async_reply_reason (struct thread_fsm *fsm);
/* Calls the FSM's should_notify_stop method. */
extern int thread_fsm_should_notify_stop (struct thread_fsm *self);
#endif /* THREAD_FSM_H */