[deliverable/binutils-gdb.git] / gdb / python / py-finishbreakpoint.c

/* Python interface to finish breakpoints

   Copyright (C) 2011-2019 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 "python-internal.h"
#include "breakpoint.h"
#include "frame.h"
#include "gdbthread.h"
#include "arch-utils.h"
#include "language.h"
#include "observable.h"
#include "inferior.h"
#include "block.h"
#include "location.h"

/* Function that is called when a Python finish bp is found out of scope.  */
static const char outofscope_func[] = "out_of_scope";

/* struct implementing the gdb.FinishBreakpoint object by extending
   the gdb.Breakpoint class.  */
struct finish_breakpoint_object
{
  /* gdb.Breakpoint base class.  */
  gdbpy_breakpoint_object py_bp;
  /* gdb.Type object of the value return by the breakpointed function.
     May be NULL if no debug information was available or return type
     was VOID.  */
  PyObject *return_type;
  /* gdb.Value object of the function finished by this breakpoint.  Will be
     NULL if return_type is NULL.  */
  PyObject *function_value;
  /* When stopped at this FinishBreakpoint, gdb.Value object returned by
     the function; Py_None if the value is not computable; NULL if GDB is
     not stopped at a FinishBreakpoint.  */
  PyObject *return_value;
};

extern PyTypeObject finish_breakpoint_object_type
    CPYCHECKER_TYPE_OBJECT_FOR_TYPEDEF ("finish_breakpoint_object");

/* Python function to get the 'return_value' attribute of
   FinishBreakpoint.  */

static PyObject *
bpfinishpy_get_returnvalue (PyObject *self, void *closure)
{
  struct finish_breakpoint_object *self_finishbp =
      (struct finish_breakpoint_object *) self;

  if (!self_finishbp->return_value)
    Py_RETURN_NONE;

  Py_INCREF (self_finishbp->return_value);
  return self_finishbp->return_value;
}

/* Deallocate FinishBreakpoint object.  */

static void
bpfinishpy_dealloc (PyObject *self)
{
  struct finish_breakpoint_object *self_bpfinish =
        (struct finish_breakpoint_object *) self;

  Py_XDECREF (self_bpfinish->function_value);
  Py_XDECREF (self_bpfinish->return_type);
  Py_XDECREF (self_bpfinish->return_value);
}

/* Triggered when gdbpy_should_stop is about to execute the `stop' callback
   of the gdb.FinishBreakpoint object BP_OBJ.  Will compute and cache the
   `return_value', if possible.  */

void
bpfinishpy_pre_stop_hook (struct gdbpy_breakpoint_object *bp_obj)
{
  struct finish_breakpoint_object *self_finishbp =
        (struct finish_breakpoint_object *) bp_obj;

  /* Can compute return_value only once.  */
  gdb_assert (!self_finishbp->return_value);

  if (!self_finishbp->return_type)
    return;

  try
    {
      struct value *function =
        value_object_to_value (self_finishbp->function_value);
      struct type *value_type =
        type_object_to_type (self_finishbp->return_type);
      struct value *ret = get_return_value (function, value_type);

      if (ret)
        {
          self_finishbp->return_value = value_to_value_object (ret);
          if (!self_finishbp->return_value)
              gdbpy_print_stack ();
        }
      else
        {
          Py_INCREF (Py_None);
          self_finishbp->return_value = Py_None;
        }
    }
  catch (const gdb_exception &except)
    {
      gdbpy_convert_exception (except);
      gdbpy_print_stack ();
    }
}

/* Triggered when gdbpy_should_stop has triggered the `stop' callback
   of the gdb.FinishBreakpoint object BP_OBJ.  */

void
bpfinishpy_post_stop_hook (struct gdbpy_breakpoint_object *bp_obj)
{

  try
    {
      /* Can't delete it here, but it will be removed at the next stop.  */
      disable_breakpoint (bp_obj->bp);
      gdb_assert (bp_obj->bp->disposition == disp_del);
    }
  catch (const gdb_exception &except)
    {
      gdbpy_convert_exception (except);
      gdbpy_print_stack ();
    }
}

/* Python function to create a new breakpoint.  */

static int
bpfinishpy_init (PyObject *self, PyObject *args, PyObject *kwargs)
{
  static const char *keywords[] = { "frame", "internal", NULL };
  struct finish_breakpoint_object *self_bpfinish =
      (struct finish_breakpoint_object *) self;
  PyObject *frame_obj = NULL;
  int thread;
  struct frame_info *frame = NULL; /* init for gcc -Wall */
  struct frame_info *prev_frame = NULL;
  struct frame_id frame_id;
  PyObject *internal = NULL;
  int internal_bp = 0;
  CORE_ADDR pc;
  struct symbol *function;

  if (!gdb_PyArg_ParseTupleAndKeywords (args, kwargs, "|OO", keywords,
					&frame_obj, &internal))
    return -1;

  try
    {
      /* Default frame to newest frame if necessary.  */
      if (frame_obj == NULL)
	frame = get_current_frame ();
      else
	frame = frame_object_to_frame_info (frame_obj);

      if (frame == NULL)
	{
	  PyErr_SetString (PyExc_ValueError,
			   _("Invalid ID for the `frame' object."));
	}
      else
	{
	  prev_frame = get_prev_frame (frame);
	  if (prev_frame == 0)
	    {
	      PyErr_SetString (PyExc_ValueError,
			       _("\"FinishBreakpoint\" not "
				 "meaningful in the outermost "
				 "frame."));
	    }
	  else if (get_frame_type (prev_frame) == DUMMY_FRAME)
	    {
	      PyErr_SetString (PyExc_ValueError,
			       _("\"FinishBreakpoint\" cannot "
				 "be set on a dummy frame."));
	    }
	  else
	    {
	      frame_id = get_frame_id (prev_frame);
	      if (frame_id_eq (frame_id, null_frame_id))
		PyErr_SetString (PyExc_ValueError,
				 _("Invalid ID for the `frame' object."));
	    }
	}
    }
  catch (const gdb_exception &except)
    {
      gdbpy_convert_exception (except);
      return -1;
    }

  if (PyErr_Occurred ())
    return -1;

  if (inferior_ptid == null_ptid)
    {
      PyErr_SetString (PyExc_ValueError,
                       _("No thread currently selected."));
      return -1;
    }

  thread = inferior_thread ()->global_num;

  if (internal)
    {
      internal_bp = PyObject_IsTrue (internal);
      if (internal_bp == -1)
        {
          PyErr_SetString (PyExc_ValueError,
                           _("The value of `internal' must be a boolean."));
          return -1;
        }
    }

  /* Find the function we will return from.  */
  self_bpfinish->return_type = NULL;
  self_bpfinish->function_value = NULL;

  try
    {
      if (get_frame_pc_if_available (frame, &pc))
        {
          function = find_pc_function (pc);
          if (function != NULL)
            {
              struct type *ret_type =
		check_typedef (TYPE_TARGET_TYPE (SYMBOL_TYPE (function)));

              /* Remember only non-void return types.  */
              if (TYPE_CODE (ret_type) != TYPE_CODE_VOID)
                {
                  struct value *func_value;

                  /* Ignore Python errors at this stage.  */
                  self_bpfinish->return_type = type_to_type_object (ret_type);
                  PyErr_Clear ();
                  func_value = read_var_value (function, NULL, frame);
                  self_bpfinish->function_value =
                      value_to_value_object (func_value);
                  PyErr_Clear ();
                }
            }
        }
    }
  catch (const gdb_exception &except)
    {
      /* Just swallow.  Either the return type or the function value
	 remain NULL.  */
    }

  if (self_bpfinish->return_type == NULL || self_bpfinish->function_value == NULL)
    {
      /* Won't be able to compute return value.  */
      Py_XDECREF (self_bpfinish->return_type);
      Py_XDECREF (self_bpfinish->function_value);

      self_bpfinish->return_type = NULL;
      self_bpfinish->function_value = NULL;
    }

  bppy_pending_object = &self_bpfinish->py_bp;
  bppy_pending_object->number = -1;
  bppy_pending_object->bp = NULL;

  try
    {
      /* Set a breakpoint on the return address.  */
      event_location_up location
	= new_address_location (get_frame_pc (prev_frame), NULL, 0);
      create_breakpoint (python_gdbarch,
                         location.get (), NULL, thread, NULL,
                         0,
                         1 /*temp_flag*/,
                         bp_breakpoint,
                         0,
                         AUTO_BOOLEAN_TRUE,
                         &bkpt_breakpoint_ops,
                         0, 1, internal_bp, 0);
    }
  catch (const gdb_exception &except)
    {
      GDB_PY_SET_HANDLE_EXCEPTION (except);
    }

  self_bpfinish->py_bp.bp->frame_id = frame_id;
  self_bpfinish->py_bp.is_finish_bp = 1;

  /* Bind the breakpoint with the current program space.  */
  self_bpfinish->py_bp.bp->pspace = current_program_space;

  return 0;
}

/* Called when GDB notices that the finish breakpoint BP_OBJ is out of
   the current callstack.  Triggers the method OUT_OF_SCOPE if implemented,
   then delete the breakpoint.  */

static void
bpfinishpy_out_of_scope (struct finish_breakpoint_object *bpfinish_obj)
{
  gdbpy_breakpoint_object *bp_obj = (gdbpy_breakpoint_object *) bpfinish_obj;
  PyObject *py_obj = (PyObject *) bp_obj;

  if (bpfinish_obj->py_bp.bp->enable_state == bp_enabled
      && PyObject_HasAttrString (py_obj, outofscope_func))
    {
      gdbpy_ref<> meth_result (PyObject_CallMethod (py_obj, outofscope_func,
						    NULL));
      if (meth_result == NULL)
	gdbpy_print_stack ();
    }

  delete_breakpoint (bpfinish_obj->py_bp.bp);
}

/* Callback for `bpfinishpy_detect_out_scope'.  Triggers Python's
   `B->out_of_scope' function if B is a FinishBreakpoint out of its scope.  */

static int
bpfinishpy_detect_out_scope_cb (struct breakpoint *b, void *args)
{
  struct breakpoint *bp_stopped = (struct breakpoint *) args;
  PyObject *py_bp = (PyObject *) b->py_bp_object;

  /* Trigger out_of_scope if this is a FinishBreakpoint and its frame is
     not anymore in the current callstack.  */
  if (py_bp != NULL && b->py_bp_object->is_finish_bp)
    {
      struct finish_breakpoint_object *finish_bp =
          (struct finish_breakpoint_object *) py_bp;

      /* Check scope if not currently stopped at the FinishBreakpoint.  */
      if (b != bp_stopped)
        {
          try
            {
              if (b->pspace == current_inferior ()->pspace
                  && (!target_has_registers
                      || frame_find_by_id (b->frame_id) == NULL))
                bpfinishpy_out_of_scope (finish_bp);
            }
          catch (const gdb_exception &except)
            {
              gdbpy_convert_exception (except);
              gdbpy_print_stack ();
            }
        }
    }

  return 0;
}

/* Attached to `stop' notifications, check if the execution has run
   out of the scope of any FinishBreakpoint before it has been hit.  */

static void
bpfinishpy_handle_stop (struct bpstats *bs, int print_frame)
{
  gdbpy_enter enter_py (get_current_arch (), current_language);

  iterate_over_breakpoints (bpfinishpy_detect_out_scope_cb,
                            bs == NULL ? NULL : bs->breakpoint_at);
}

/* Attached to `exit' notifications, triggers all the necessary out of
   scope notifications.  */

static void
bpfinishpy_handle_exit (struct inferior *inf)
{
  gdbpy_enter enter_py (target_gdbarch (), current_language);

  iterate_over_breakpoints (bpfinishpy_detect_out_scope_cb, NULL);
}

/* Initialize the Python finish breakpoint code.  */

int
gdbpy_initialize_finishbreakpoints (void)
{
  if (PyType_Ready (&finish_breakpoint_object_type) < 0)
    return -1;

  if (gdb_pymodule_addobject (gdb_module, "FinishBreakpoint",
			      (PyObject *) &finish_breakpoint_object_type) < 0)
    return -1;

  gdb::observers::normal_stop.attach (bpfinishpy_handle_stop);
  gdb::observers::inferior_exit.attach (bpfinishpy_handle_exit);

  return 0;
}

static gdb_PyGetSetDef finish_breakpoint_object_getset[] = {
  { "return_value", bpfinishpy_get_returnvalue, NULL,
  "gdb.Value object representing the return value, if any. \
None otherwise.", NULL },
    { NULL }  /* Sentinel.  */
};

PyTypeObject finish_breakpoint_object_type =
{
  PyVarObject_HEAD_INIT (NULL, 0)
  "gdb.FinishBreakpoint",         /*tp_name*/
  sizeof (struct finish_breakpoint_object),  /*tp_basicsize*/
  0,                              /*tp_itemsize*/
  bpfinishpy_dealloc,             /*tp_dealloc*/
  0,                              /*tp_print*/
  0,                              /*tp_getattr*/
  0,                              /*tp_setattr*/
  0,                              /*tp_compare*/
  0,                              /*tp_repr*/
  0,                              /*tp_as_number*/
  0,                              /*tp_as_sequence*/
  0,                              /*tp_as_mapping*/
  0,                              /*tp_hash */
  0,                              /*tp_call*/
  0,                              /*tp_str*/
  0,                              /*tp_getattro*/
  0,                              /*tp_setattro */
  0,                              /*tp_as_buffer*/
  Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE,  /*tp_flags*/
  "GDB finish breakpoint object", /* tp_doc */
  0,                              /* tp_traverse */
  0,                              /* tp_clear */
  0,                              /* tp_richcompare */
  0,                              /* tp_weaklistoffset */
  0,                              /* tp_iter */
  0,                              /* tp_iternext */
  0,                              /* tp_methods */
  0,                              /* tp_members */
  finish_breakpoint_object_getset,/* tp_getset */
  &breakpoint_object_type,        /* tp_base */
  0,                              /* tp_dict */
  0,                              /* tp_descr_get */
  0,                              /* tp_descr_set */
  0,                              /* tp_dictoffset */
  bpfinishpy_init,                /* tp_init */
  0,                              /* tp_alloc */
  0                               /* tp_new */
};
Commit	Line	Data
cc72b2a2 KP	1	/* Python interface to finish breakpoints
cc72b2a2 KP	2
42a4f53d	3	Copyright (C) 2011-2019 Free Software Foundation, Inc.
cc72b2a2 KP	4
	5	This file is part of GDB.
	6
	7	This program is free software; you can redistribute it and/or modify
	8	it under the terms of the GNU General Public License as published by
	9	the Free Software Foundation; either version 3 of the License, or
	10	(at your option) any later version.
	11
	12	This program is distributed in the hope that it will be useful,
	13	but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	GNU General Public License for more details.
	16
	17	You should have received a copy of the GNU General Public License
	18	along with this program. If not, see <http://www.gnu.org/licenses/>. */
	19
	20
	21
	22	#include "defs.h"
cc72b2a2 KP	23	#include "python-internal.h"
	24	#include "breakpoint.h"
	25	#include "frame.h"
	26	#include "gdbthread.h"
	27	#include "arch-utils.h"
	28	#include "language.h"
76727919	29	#include "observable.h"
cc72b2a2	30	#include "inferior.h"
6a3a010b	31	#include "block.h"
f00aae0f	32	#include "location.h"
cc72b2a2	33
cc72b2a2	34	/* Function that is called when a Python finish bp is found out of scope. */
a121b7c1	35	static const char outofscope_func[] = "out_of_scope";
cc72b2a2 KP	36
	37	/* struct implementing the gdb.FinishBreakpoint object by extending
	38	the gdb.Breakpoint class. */
	39	struct finish_breakpoint_object
	40	{
	41	/* gdb.Breakpoint base class. */
4cb0213d	42	gdbpy_breakpoint_object py_bp;
cc72b2a2 KP	43	/* gdb.Type object of the value return by the breakpointed function.
	44	May be NULL if no debug information was available or return type
	45	was VOID. */
	46	PyObject *return_type;
6a3a010b	47	/* gdb.Value object of the function finished by this breakpoint. Will be
cc72b2a2	48	NULL if return_type is NULL. */
6a3a010b	49	PyObject *function_value;
cc72b2a2 KP	50	/* When stopped at this FinishBreakpoint, gdb.Value object returned by
	51	the function; Py_None if the value is not computable; NULL if GDB is
	52	not stopped at a FinishBreakpoint. */
	53	PyObject *return_value;
	54	};
	55
e36122e9	56	extern PyTypeObject finish_breakpoint_object_type
62eec1a5 TT	57	CPYCHECKER_TYPE_OBJECT_FOR_TYPEDEF ("finish_breakpoint_object");
62eec1a5 TT	58
cc72b2a2 KP	59	/* Python function to get the 'return_value' attribute of
	60	FinishBreakpoint. */
	61
	62	static PyObject *
	63	bpfinishpy_get_returnvalue (PyObject self, void closure)
	64	{
	65	struct finish_breakpoint_object *self_finishbp =
	66	(struct finish_breakpoint_object *) self;
	67
	68	if (!self_finishbp->return_value)
	69	Py_RETURN_NONE;
	70
	71	Py_INCREF (self_finishbp->return_value);
	72	return self_finishbp->return_value;
	73	}
	74
	75	/* Deallocate FinishBreakpoint object. */
	76
	77	static void
	78	bpfinishpy_dealloc (PyObject *self)
	79	{
	80	struct finish_breakpoint_object *self_bpfinish =
	81	(struct finish_breakpoint_object *) self;
	82
6a3a010b	83	Py_XDECREF (self_bpfinish->function_value);
cc72b2a2 KP	84	Py_XDECREF (self_bpfinish->return_type);
	85	Py_XDECREF (self_bpfinish->return_value);
	86	}
	87
	88	/* Triggered when gdbpy_should_stop is about to execute the `stop' callback
	89	of the gdb.FinishBreakpoint object BP_OBJ. Will compute and cache the
	90	`return_value', if possible. */
	91
	92	void
4cb0213d	93	bpfinishpy_pre_stop_hook (struct gdbpy_breakpoint_object *bp_obj)
cc72b2a2 KP	94	{
	95	struct finish_breakpoint_object *self_finishbp =
	96	(struct finish_breakpoint_object *) bp_obj;
cc72b2a2 KP	97
	98	/* Can compute return_value only once. */
	99	gdb_assert (!self_finishbp->return_value);
	100
	101	if (!self_finishbp->return_type)
	102	return;
	103
a70b8144	104	try
cc72b2a2	105	{
6a3a010b MR	106	struct value *function =
	107	value_object_to_value (self_finishbp->function_value);
	108	struct type *value_type =
	109	type_object_to_type (self_finishbp->return_type);
0700e23e	110	struct value *ret = get_return_value (function, value_type);
cc72b2a2 KP	111
	112	if (ret)
	113	{
	114	self_finishbp->return_value = value_to_value_object (ret);
	115	if (!self_finishbp->return_value)
	116	gdbpy_print_stack ();
	117	}
	118	else
	119	{
	120	Py_INCREF (Py_None);
	121	self_finishbp->return_value = Py_None;
	122	}
	123	}
230d2906	124	catch (const gdb_exception &except)
cc72b2a2 KP	125	{
	126	gdbpy_convert_exception (except);
	127	gdbpy_print_stack ();
	128	}
	129	}
	130
	131	/* Triggered when gdbpy_should_stop has triggered the `stop' callback
	132	of the gdb.FinishBreakpoint object BP_OBJ. */
	133
	134	void
4cb0213d	135	bpfinishpy_post_stop_hook (struct gdbpy_breakpoint_object *bp_obj)
cc72b2a2	136	{
cc72b2a2	137
a70b8144	138	try
cc72b2a2 KP	139	{
	140	/* Can't delete it here, but it will be removed at the next stop. */
	141	disable_breakpoint (bp_obj->bp);
	142	gdb_assert (bp_obj->bp->disposition == disp_del);
	143	}
230d2906	144	catch (const gdb_exception &except)
cc72b2a2 KP	145	{
	146	gdbpy_convert_exception (except);
	147	gdbpy_print_stack ();
	148	}
	149	}
	150
	151	/* Python function to create a new breakpoint. */
	152
	153	static int
	154	bpfinishpy_init (PyObject self, PyObject args, PyObject *kwargs)
	155	{
2adadf51	156	static const char *keywords[] = { "frame", "internal", NULL };
cc72b2a2 KP	157	struct finish_breakpoint_object *self_bpfinish =
cc72b2a2 KP	158	(struct finish_breakpoint_object *) self;
cc72b2a2 KP	159	PyObject *frame_obj = NULL;
cc72b2a2 KP	160	int thread;
62d7fb51 DE	161	struct frame_info frame = NULL; / init for gcc -Wall */
62d7fb51 DE	162	struct frame_info *prev_frame = NULL;
cc72b2a2 KP	163	struct frame_id frame_id;
	164	PyObject *internal = NULL;
	165	int internal_bp = 0;
a06efdd6	166	CORE_ADDR pc;
cc72b2a2 KP	167	struct symbol *function;
cc72b2a2 KP	168
2adadf51 PA	169	if (!gdb_PyArg_ParseTupleAndKeywords (args, kwargs, "\|OO", keywords,
2adadf51 PA	170	&frame_obj, &internal))
cc72b2a2 KP	171	return -1;
cc72b2a2 KP	172
a70b8144	173	try
cc72b2a2	174	{
dd5fa3e7 TT	175	/* Default frame to newest frame if necessary. */
	176	if (frame_obj == NULL)
	177	frame = get_current_frame ();
cc72b2a2	178	else
dd5fa3e7 TT	179	frame = frame_object_to_frame_info (frame_obj);
	180
	181	if (frame == NULL)
	182	{
256458bc	183	PyErr_SetString (PyExc_ValueError,
dd5fa3e7 TT	184	_("Invalid ID for the `frame' object."));
	185	}
	186	else
	187	{
	188	prev_frame = get_prev_frame (frame);
	189	if (prev_frame == 0)
	190	{
	191	PyErr_SetString (PyExc_ValueError,
	192	_("\"FinishBreakpoint\" not "
	193	"meaningful in the outermost "
	194	"frame."));
	195	}
	196	else if (get_frame_type (prev_frame) == DUMMY_FRAME)
	197	{
	198	PyErr_SetString (PyExc_ValueError,
	199	_("\"FinishBreakpoint\" cannot "
	200	"be set on a dummy frame."));
	201	}
	202	else
	203	{
	204	frame_id = get_frame_id (prev_frame);
	205	if (frame_id_eq (frame_id, null_frame_id))
	206	PyErr_SetString (PyExc_ValueError,
	207	_("Invalid ID for the `frame' object."));
	208	}
	209	}
cc72b2a2	210	}
230d2906	211	catch (const gdb_exception &except)
cc72b2a2 KP	212	{
	213	gdbpy_convert_exception (except);
	214	return -1;
	215	}
492d29ea PA	216
492d29ea PA	217	if (PyErr_Occurred ())
cc72b2a2 KP	218	return -1;
cc72b2a2 KP	219
00431a78	220	if (inferior_ptid == null_ptid)
cc72b2a2 KP	221	{
	222	PyErr_SetString (PyExc_ValueError,
	223	_("No thread currently selected."));
	224	return -1;
	225	}
	226
00431a78 PA	227	thread = inferior_thread ()->global_num;
00431a78 PA	228
cc72b2a2 KP	229	if (internal)
	230	{
	231	internal_bp = PyObject_IsTrue (internal);
256458bc	232	if (internal_bp == -1)
cc72b2a2	233	{
256458bc	234	PyErr_SetString (PyExc_ValueError,
cc72b2a2 KP	235	_("The value of `internal' must be a boolean."));
	236	return -1;
	237	}
	238	}
	239
	240	/* Find the function we will return from. */
	241	self_bpfinish->return_type = NULL;
6a3a010b	242	self_bpfinish->function_value = NULL;
cc72b2a2	243
a70b8144	244	try
cc72b2a2 KP	245	{
	246	if (get_frame_pc_if_available (frame, &pc))
	247	{
	248	function = find_pc_function (pc);
	249	if (function != NULL)
	250	{
	251	struct type *ret_type =
f097f5ad	252	check_typedef (TYPE_TARGET_TYPE (SYMBOL_TYPE (function)));
cc72b2a2 KP	253
	254	/* Remember only non-void return types. */
	255	if (TYPE_CODE (ret_type) != TYPE_CODE_VOID)
	256	{
6a3a010b MR	257	struct value *func_value;
6a3a010b MR	258
cc72b2a2 KP	259	/* Ignore Python errors at this stage. */
	260	self_bpfinish->return_type = type_to_type_object (ret_type);
	261	PyErr_Clear ();
63e43d3a	262	func_value = read_var_value (function, NULL, frame);
6a3a010b MR	263	self_bpfinish->function_value =
6a3a010b MR	264	value_to_value_object (func_value);
cc72b2a2 KP	265	PyErr_Clear ();
	266	}
	267	}
	268	}
	269	}
230d2906	270	catch (const gdb_exception &except)
7556d4a4 PA	271	{
	272	/* Just swallow. Either the return type or the function value
	273	remain NULL. */
	274	}
	275
	276	if (self_bpfinish->return_type == NULL \|\| self_bpfinish->function_value == NULL)
cc72b2a2 KP	277	{
	278	/* Won't be able to compute return value. */
	279	Py_XDECREF (self_bpfinish->return_type);
6a3a010b	280	Py_XDECREF (self_bpfinish->function_value);
cc72b2a2 KP	281
cc72b2a2 KP	282	self_bpfinish->return_type = NULL;
6a3a010b	283	self_bpfinish->function_value = NULL;
cc72b2a2 KP	284	}
	285
	286	bppy_pending_object = &self_bpfinish->py_bp;
	287	bppy_pending_object->number = -1;
	288	bppy_pending_object->bp = NULL;
	289
a70b8144	290	try
cc72b2a2 KP	291	{
cc72b2a2 KP	292	/* Set a breakpoint on the return address. */
ffc2605c TT	293	event_location_up location
ffc2605c TT	294	= new_address_location (get_frame_pc (prev_frame), NULL, 0);
cc72b2a2	295	create_breakpoint (python_gdbarch,
ffc2605c	296	location.get (), NULL, thread, NULL,
cc72b2a2 KP	297	0,
	298	1 /temp_flag/,
	299	bp_breakpoint,
	300	0,
	301	AUTO_BOOLEAN_TRUE,
	302	&bkpt_breakpoint_ops,
44f238bb	303	0, 1, internal_bp, 0);
cc72b2a2	304	}
230d2906	305	catch (const gdb_exception &except)
492d29ea PA	306	{
	307	GDB_PY_SET_HANDLE_EXCEPTION (except);
	308	}
256458bc	309
cc72b2a2 KP	310	self_bpfinish->py_bp.bp->frame_id = frame_id;
cc72b2a2 KP	311	self_bpfinish->py_bp.is_finish_bp = 1;
256458bc	312
cc72b2a2 KP	313	/* Bind the breakpoint with the current program space. */
	314	self_bpfinish->py_bp.bp->pspace = current_program_space;
	315
	316	return 0;
cc72b2a2 KP	317	}
	318
	319	/* Called when GDB notices that the finish breakpoint BP_OBJ is out of
	320	the current callstack. Triggers the method OUT_OF_SCOPE if implemented,
	321	then delete the breakpoint. */
	322
	323	static void
	324	bpfinishpy_out_of_scope (struct finish_breakpoint_object *bpfinish_obj)
	325	{
4cb0213d	326	gdbpy_breakpoint_object bp_obj = (gdbpy_breakpoint_object ) bpfinish_obj;
cc72b2a2 KP	327	PyObject py_obj = (PyObject ) bp_obj;
	328
	329	if (bpfinish_obj->py_bp.bp->enable_state == bp_enabled
	330	&& PyObject_HasAttrString (py_obj, outofscope_func))
	331	{
7780f186 TT	332	gdbpy_ref<> meth_result (PyObject_CallMethod (py_obj, outofscope_func,
7780f186 TT	333	NULL));
18868860 TT	334	if (meth_result == NULL)
18868860 TT	335	gdbpy_print_stack ();
cc72b2a2 KP	336	}
	337
	338	delete_breakpoint (bpfinish_obj->py_bp.bp);
	339	}
	340
	341	/* Callback for `bpfinishpy_detect_out_scope'. Triggers Python's
	342	`B->out_of_scope' function if B is a FinishBreakpoint out of its scope. */
	343
	344	static int
	345	bpfinishpy_detect_out_scope_cb (struct breakpoint b, void args)
	346	{
cc72b2a2 KP	347	struct breakpoint bp_stopped = (struct breakpoint ) args;
cc72b2a2 KP	348	PyObject py_bp = (PyObject ) b->py_bp_object;
256458bc	349
cc72b2a2 KP	350	/* Trigger out_of_scope if this is a FinishBreakpoint and its frame is
	351	not anymore in the current callstack. */
	352	if (py_bp != NULL && b->py_bp_object->is_finish_bp)
	353	{
	354	struct finish_breakpoint_object *finish_bp =
	355	(struct finish_breakpoint_object *) py_bp;
	356
	357	/* Check scope if not currently stopped at the FinishBreakpoint. */
	358	if (b != bp_stopped)
	359	{
a70b8144	360	try
cc72b2a2 KP	361	{
	362	if (b->pspace == current_inferior ()->pspace
	363	&& (!target_has_registers
	364	\|\| frame_find_by_id (b->frame_id) == NULL))
	365	bpfinishpy_out_of_scope (finish_bp);
	366	}
230d2906	367	catch (const gdb_exception &except)
cc72b2a2 KP	368	{
	369	gdbpy_convert_exception (except);
	370	gdbpy_print_stack ();
	371	}
	372	}
	373	}
	374
	375	return 0;
	376	}
	377
	378	/* Attached to `stop' notifications, check if the execution has run
	379	out of the scope of any FinishBreakpoint before it has been hit. */
	380
	381	static void
	382	bpfinishpy_handle_stop (struct bpstats *bs, int print_frame)
	383	{
6e7c365e	384	gdbpy_enter enter_py (get_current_arch (), current_language);
cc72b2a2 KP	385
	386	iterate_over_breakpoints (bpfinishpy_detect_out_scope_cb,
	387	bs == NULL ? NULL : bs->breakpoint_at);
cc72b2a2 KP	388	}
	389
	390	/* Attached to `exit' notifications, triggers all the necessary out of
	391	scope notifications. */
	392
	393	static void
	394	bpfinishpy_handle_exit (struct inferior *inf)
	395	{
6e7c365e	396	gdbpy_enter enter_py (target_gdbarch (), current_language);
cc72b2a2 KP	397
cc72b2a2 KP	398	iterate_over_breakpoints (bpfinishpy_detect_out_scope_cb, NULL);
cc72b2a2 KP	399	}
	400
	401	/* Initialize the Python finish breakpoint code. */
	402
999633ed	403	int
cc72b2a2 KP	404	gdbpy_initialize_finishbreakpoints (void)
	405	{
	406	if (PyType_Ready (&finish_breakpoint_object_type) < 0)
999633ed	407	return -1;
256458bc	408
aa36459a TT	409	if (gdb_pymodule_addobject (gdb_module, "FinishBreakpoint",
aa36459a TT	410	(PyObject *) &finish_breakpoint_object_type) < 0)
999633ed	411	return -1;
256458bc	412
76727919 TT	413	gdb::observers::normal_stop.attach (bpfinishpy_handle_stop);
76727919 TT	414	gdb::observers::inferior_exit.attach (bpfinishpy_handle_exit);
999633ed TT	415
999633ed TT	416	return 0;
cc72b2a2 KP	417	}
cc72b2a2 KP	418
0d1f4ceb	419	static gdb_PyGetSetDef finish_breakpoint_object_getset[] = {
cc72b2a2 KP	420	{ "return_value", bpfinishpy_get_returnvalue, NULL,
	421	"gdb.Value object representing the return value, if any. \
	422	None otherwise.", NULL },
	423	{ NULL } /* Sentinel. */
	424	};
	425
e36122e9	426	PyTypeObject finish_breakpoint_object_type =
cc72b2a2	427	{
9a27f2c6	428	PyVarObject_HEAD_INIT (NULL, 0)
cc72b2a2 KP	429	"gdb.FinishBreakpoint", /tp_name/
	430	sizeof (struct finish_breakpoint_object), /tp_basicsize/
	431	0, /tp_itemsize/
	432	bpfinishpy_dealloc, /tp_dealloc/
	433	0, /tp_print/
	434	0, /tp_getattr/
	435	0, /tp_setattr/
	436	0, /tp_compare/
	437	0, /tp_repr/
	438	0, /tp_as_number/
	439	0, /tp_as_sequence/
	440	0, /tp_as_mapping/
	441	0, /tp_hash /
	442	0, /tp_call/
	443	0, /tp_str/
	444	0, /tp_getattro/
	445	0, /tp_setattro /
	446	0, /tp_as_buffer/
	447	Py_TPFLAGS_DEFAULT \| Py_TPFLAGS_BASETYPE, /tp_flags/
	448	"GDB finish breakpoint object", /* tp_doc */
	449	0, /* tp_traverse */
	450	0, /* tp_clear */
	451	0, /* tp_richcompare */
	452	0, /* tp_weaklistoffset */
	453	0, /* tp_iter */
	454	0, /* tp_iternext */
	455	0, /* tp_methods */
	456	0, /* tp_members */
	457	finish_breakpoint_object_getset,/* tp_getset */
	458	&breakpoint_object_type, /* tp_base */
	459	0, /* tp_dict */
	460	0, /* tp_descr_get */
	461	0, /* tp_descr_set */
	462	0, /* tp_dictoffset */
	463	bpfinishpy_init, /* tp_init */
	464	0, /* tp_alloc */
	465	0 /* tp_new */
	466	};