xref: /netbsd-src/external/gpl3/gdb.old/dist/gdb/python/py-breakpoint.c (revision 200d779b75dbeafa7bc01fd0f60bc61185f6967b)
1 /* Python interface to breakpoints
2 
3    Copyright (C) 2008-2014 Free Software Foundation, Inc.
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 #include "defs.h"
21 #include "value.h"
22 #include "exceptions.h"
23 #include "python-internal.h"
24 #include "python.h"
25 #include "charset.h"
26 #include "breakpoint.h"
27 #include "gdbcmd.h"
28 #include "gdbthread.h"
29 #include "observer.h"
30 #include "cli/cli-script.h"
31 #include "ada-lang.h"
32 #include "arch-utils.h"
33 #include "language.h"
34 
35 /* Number of live breakpoints.  */
36 static int bppy_live;
37 
38 /* Variables used to pass information between the Breakpoint
39    constructor and the breakpoint-created hook function.  */
40 gdbpy_breakpoint_object *bppy_pending_object;
41 
42 /* Function that is called when a Python condition is evaluated.  */
43 static char * const stop_func = "stop";
44 
45 /* This is used to initialize various gdb.bp_* constants.  */
46 struct pybp_code
47 {
48   /* The name.  */
49   const char *name;
50   /* The code.  */
51   int code;
52 };
53 
54 /* Entries related to the type of user set breakpoints.  */
55 static struct pybp_code pybp_codes[] =
56 {
57   { "BP_NONE", bp_none},
58   { "BP_BREAKPOINT", bp_breakpoint},
59   { "BP_WATCHPOINT", bp_watchpoint},
60   { "BP_HARDWARE_WATCHPOINT", bp_hardware_watchpoint},
61   { "BP_READ_WATCHPOINT", bp_read_watchpoint},
62   { "BP_ACCESS_WATCHPOINT", bp_access_watchpoint},
63   {NULL} /* Sentinel.  */
64 };
65 
66 /* Entries related to the type of watchpoint.  */
67 static struct pybp_code pybp_watch_types[] =
68 {
69   { "WP_READ", hw_read},
70   { "WP_WRITE", hw_write},
71   { "WP_ACCESS", hw_access},
72   {NULL} /* Sentinel.  */
73 };
74 
75 /* Python function which checks the validity of a breakpoint object.  */
76 static PyObject *
77 bppy_is_valid (PyObject *self, PyObject *args)
78 {
79   gdbpy_breakpoint_object *self_bp = (gdbpy_breakpoint_object *) self;
80 
81   if (self_bp->bp)
82     Py_RETURN_TRUE;
83   Py_RETURN_FALSE;
84 }
85 
86 /* Python function to test whether or not the breakpoint is enabled.  */
87 static PyObject *
88 bppy_get_enabled (PyObject *self, void *closure)
89 {
90   gdbpy_breakpoint_object *self_bp = (gdbpy_breakpoint_object *) self;
91 
92   BPPY_REQUIRE_VALID (self_bp);
93   if (! self_bp->bp)
94     Py_RETURN_FALSE;
95   if (self_bp->bp->enable_state == bp_enabled)
96     Py_RETURN_TRUE;
97   Py_RETURN_FALSE;
98 }
99 
100 /* Python function to test whether or not the breakpoint is silent.  */
101 static PyObject *
102 bppy_get_silent (PyObject *self, void *closure)
103 {
104   gdbpy_breakpoint_object *self_bp = (gdbpy_breakpoint_object *) self;
105 
106   BPPY_REQUIRE_VALID (self_bp);
107   if (self_bp->bp->silent)
108     Py_RETURN_TRUE;
109   Py_RETURN_FALSE;
110 }
111 
112 /* Python function to set the enabled state of a breakpoint.  */
113 static int
114 bppy_set_enabled (PyObject *self, PyObject *newvalue, void *closure)
115 {
116   gdbpy_breakpoint_object *self_bp = (gdbpy_breakpoint_object *) self;
117   int cmp;
118   volatile struct gdb_exception except;
119 
120   BPPY_SET_REQUIRE_VALID (self_bp);
121 
122   if (newvalue == NULL)
123     {
124       PyErr_SetString (PyExc_TypeError,
125 		       _("Cannot delete `enabled' attribute."));
126 
127       return -1;
128     }
129   else if (! PyBool_Check (newvalue))
130     {
131       PyErr_SetString (PyExc_TypeError,
132 		       _("The value of `enabled' must be a boolean."));
133       return -1;
134     }
135 
136   cmp = PyObject_IsTrue (newvalue);
137   if (cmp < 0)
138     return -1;
139 
140   TRY_CATCH (except, RETURN_MASK_ALL)
141     {
142       if (cmp == 1)
143 	enable_breakpoint (self_bp->bp);
144       else
145 	disable_breakpoint (self_bp->bp);
146     }
147   GDB_PY_SET_HANDLE_EXCEPTION (except);
148 
149   return 0;
150 }
151 
152 /* Python function to set the 'silent' state of a breakpoint.  */
153 static int
154 bppy_set_silent (PyObject *self, PyObject *newvalue, void *closure)
155 {
156   gdbpy_breakpoint_object *self_bp = (gdbpy_breakpoint_object *) self;
157   int cmp;
158 
159   BPPY_SET_REQUIRE_VALID (self_bp);
160 
161   if (newvalue == NULL)
162     {
163       PyErr_SetString (PyExc_TypeError,
164 		       _("Cannot delete `silent' attribute."));
165       return -1;
166     }
167   else if (! PyBool_Check (newvalue))
168     {
169       PyErr_SetString (PyExc_TypeError,
170 		       _("The value of `silent' must be a boolean."));
171       return -1;
172     }
173 
174   cmp = PyObject_IsTrue (newvalue);
175   if (cmp < 0)
176     return -1;
177   else
178     breakpoint_set_silent (self_bp->bp, cmp);
179 
180   return 0;
181 }
182 
183 /* Python function to set the thread of a breakpoint.  */
184 static int
185 bppy_set_thread (PyObject *self, PyObject *newvalue, void *closure)
186 {
187   gdbpy_breakpoint_object *self_bp = (gdbpy_breakpoint_object *) self;
188   long id;
189 
190   BPPY_SET_REQUIRE_VALID (self_bp);
191 
192   if (newvalue == NULL)
193     {
194       PyErr_SetString (PyExc_TypeError,
195 		       _("Cannot delete `thread' attribute."));
196       return -1;
197     }
198   else if (PyInt_Check (newvalue))
199     {
200       if (! gdb_py_int_as_long (newvalue, &id))
201 	return -1;
202 
203       if (! valid_thread_id (id))
204 	{
205 	  PyErr_SetString (PyExc_RuntimeError,
206 			   _("Invalid thread ID."));
207 	  return -1;
208 	}
209     }
210   else if (newvalue == Py_None)
211     id = -1;
212   else
213     {
214       PyErr_SetString (PyExc_TypeError,
215 		       _("The value of `thread' must be an integer or None."));
216       return -1;
217     }
218 
219   breakpoint_set_thread (self_bp->bp, id);
220 
221   return 0;
222 }
223 
224 /* Python function to set the (Ada) task of a breakpoint.  */
225 static int
226 bppy_set_task (PyObject *self, PyObject *newvalue, void *closure)
227 {
228   gdbpy_breakpoint_object *self_bp = (gdbpy_breakpoint_object *) self;
229   long id;
230   int valid_id = 0;
231   volatile struct gdb_exception except;
232 
233   BPPY_SET_REQUIRE_VALID (self_bp);
234 
235   if (newvalue == NULL)
236     {
237       PyErr_SetString (PyExc_TypeError,
238 		       _("Cannot delete `task' attribute."));
239       return -1;
240     }
241   else if (PyInt_Check (newvalue))
242     {
243       if (! gdb_py_int_as_long (newvalue, &id))
244 	return -1;
245 
246       TRY_CATCH (except, RETURN_MASK_ALL)
247 	{
248 	  valid_id = valid_task_id (id);
249 	}
250       GDB_PY_SET_HANDLE_EXCEPTION (except);
251 
252       if (! valid_id)
253 	{
254 	  PyErr_SetString (PyExc_RuntimeError,
255 			   _("Invalid task ID."));
256 	  return -1;
257 	}
258     }
259   else if (newvalue == Py_None)
260     id = 0;
261   else
262     {
263       PyErr_SetString (PyExc_TypeError,
264 		       _("The value of `task' must be an integer or None."));
265       return -1;
266     }
267 
268   breakpoint_set_task (self_bp->bp, id);
269 
270   return 0;
271 }
272 
273 /* Python function which deletes the underlying GDB breakpoint.  This
274    triggers the breakpoint_deleted observer which will call
275    gdbpy_breakpoint_deleted; that function cleans up the Python
276    sections.  */
277 
278 static PyObject *
279 bppy_delete_breakpoint (PyObject *self, PyObject *args)
280 {
281   gdbpy_breakpoint_object *self_bp = (gdbpy_breakpoint_object *) self;
282   volatile struct gdb_exception except;
283 
284   BPPY_REQUIRE_VALID (self_bp);
285 
286   TRY_CATCH (except, RETURN_MASK_ALL)
287     {
288       delete_breakpoint (self_bp->bp);
289     }
290   GDB_PY_HANDLE_EXCEPTION (except);
291 
292   Py_RETURN_NONE;
293 }
294 
295 
296 /* Python function to set the ignore count of a breakpoint.  */
297 static int
298 bppy_set_ignore_count (PyObject *self, PyObject *newvalue, void *closure)
299 {
300   gdbpy_breakpoint_object *self_bp = (gdbpy_breakpoint_object *) self;
301   long value;
302   volatile struct gdb_exception except;
303 
304   BPPY_SET_REQUIRE_VALID (self_bp);
305 
306   if (newvalue == NULL)
307     {
308       PyErr_SetString (PyExc_TypeError,
309 		       _("Cannot delete `ignore_count' attribute."));
310       return -1;
311     }
312   else if (! PyInt_Check (newvalue))
313     {
314       PyErr_SetString (PyExc_TypeError,
315 		       _("The value of `ignore_count' must be an integer."));
316       return -1;
317     }
318 
319   if (! gdb_py_int_as_long (newvalue, &value))
320     return -1;
321 
322   if (value < 0)
323     value = 0;
324 
325   TRY_CATCH (except, RETURN_MASK_ALL)
326     {
327       set_ignore_count (self_bp->number, (int) value, 0);
328     }
329   GDB_PY_SET_HANDLE_EXCEPTION (except);
330 
331   return 0;
332 }
333 
334 /* Python function to set the hit count of a breakpoint.  */
335 static int
336 bppy_set_hit_count (PyObject *self, PyObject *newvalue, void *closure)
337 {
338   gdbpy_breakpoint_object *self_bp = (gdbpy_breakpoint_object *) self;
339 
340   BPPY_SET_REQUIRE_VALID (self_bp);
341 
342   if (newvalue == NULL)
343     {
344       PyErr_SetString (PyExc_TypeError,
345 		       _("Cannot delete `hit_count' attribute."));
346       return -1;
347     }
348   else
349     {
350       long value;
351 
352       if (! gdb_py_int_as_long (newvalue, &value))
353 	return -1;
354 
355       if (value != 0)
356 	{
357 	  PyErr_SetString (PyExc_AttributeError,
358 			   _("The value of `hit_count' must be zero."));
359 	  return -1;
360 	}
361     }
362 
363   self_bp->bp->hit_count = 0;
364 
365   return 0;
366 }
367 
368 /* Python function to get the location of a breakpoint.  */
369 static PyObject *
370 bppy_get_location (PyObject *self, void *closure)
371 {
372   char *str;
373   gdbpy_breakpoint_object *obj = (gdbpy_breakpoint_object *) self;
374 
375   BPPY_REQUIRE_VALID (obj);
376 
377   if (obj->bp->type != bp_breakpoint)
378     Py_RETURN_NONE;
379 
380   str = obj->bp->addr_string;
381 
382   if (! str)
383     str = "";
384   return PyString_Decode (str, strlen (str), host_charset (), NULL);
385 }
386 
387 /* Python function to get the breakpoint expression.  */
388 static PyObject *
389 bppy_get_expression (PyObject *self, void *closure)
390 {
391   char *str;
392   gdbpy_breakpoint_object *obj = (gdbpy_breakpoint_object *) self;
393   struct watchpoint *wp;
394 
395   BPPY_REQUIRE_VALID (obj);
396 
397   if (!is_watchpoint (obj->bp))
398     Py_RETURN_NONE;
399 
400   wp = (struct watchpoint *) obj->bp;
401 
402   str = wp->exp_string;
403   if (! str)
404     str = "";
405 
406   return PyString_Decode (str, strlen (str), host_charset (), NULL);
407 }
408 
409 /* Python function to get the condition expression of a breakpoint.  */
410 static PyObject *
411 bppy_get_condition (PyObject *self, void *closure)
412 {
413   char *str;
414   gdbpy_breakpoint_object *obj = (gdbpy_breakpoint_object *) self;
415 
416   BPPY_REQUIRE_VALID (obj);
417 
418   str = obj->bp->cond_string;
419   if (! str)
420     Py_RETURN_NONE;
421 
422   return PyString_Decode (str, strlen (str), host_charset (), NULL);
423 }
424 
425 /* Returns 0 on success.  Returns -1 on error, with a python exception set.
426    */
427 
428 static int
429 bppy_set_condition (PyObject *self, PyObject *newvalue, void *closure)
430 {
431   char *exp;
432   gdbpy_breakpoint_object *self_bp = (gdbpy_breakpoint_object *) self;
433   volatile struct gdb_exception except;
434 
435   BPPY_SET_REQUIRE_VALID (self_bp);
436 
437   if (newvalue == NULL)
438     {
439       PyErr_SetString (PyExc_TypeError,
440 		       _("Cannot delete `condition' attribute."));
441       return -1;
442     }
443   else if (newvalue == Py_None)
444     exp = "";
445   else
446     {
447       exp = python_string_to_host_string (newvalue);
448       if (exp == NULL)
449 	return -1;
450     }
451 
452   TRY_CATCH (except, RETURN_MASK_ALL)
453     {
454       set_breakpoint_condition (self_bp->bp, exp, 0);
455     }
456 
457   if (newvalue != Py_None)
458     xfree (exp);
459 
460   GDB_PY_SET_HANDLE_EXCEPTION (except);
461 
462   return 0;
463 }
464 
465 /* Python function to get the commands attached to a breakpoint.  */
466 static PyObject *
467 bppy_get_commands (PyObject *self, void *closure)
468 {
469   gdbpy_breakpoint_object *self_bp = (gdbpy_breakpoint_object *) self;
470   struct breakpoint *bp = self_bp->bp;
471   long length;
472   volatile struct gdb_exception except;
473   struct ui_file *string_file;
474   struct cleanup *chain;
475   PyObject *result;
476   char *cmdstr;
477 
478   BPPY_REQUIRE_VALID (self_bp);
479 
480   if (! self_bp->bp->commands)
481     Py_RETURN_NONE;
482 
483   string_file = mem_fileopen ();
484   chain = make_cleanup_ui_file_delete (string_file);
485 
486   ui_out_redirect (current_uiout, string_file);
487   TRY_CATCH (except, RETURN_MASK_ALL)
488     {
489       print_command_lines (current_uiout, breakpoint_commands (bp), 0);
490     }
491   ui_out_redirect (current_uiout, NULL);
492   if (except.reason < 0)
493     {
494       do_cleanups (chain);
495       gdbpy_convert_exception (except);
496       return NULL;
497     }
498 
499   cmdstr = ui_file_xstrdup (string_file, &length);
500   make_cleanup (xfree, cmdstr);
501   result = PyString_Decode (cmdstr, strlen (cmdstr), host_charset (), NULL);
502   do_cleanups (chain);
503   return result;
504 }
505 
506 /* Python function to get the breakpoint type.  */
507 static PyObject *
508 bppy_get_type (PyObject *self, void *closure)
509 {
510   gdbpy_breakpoint_object *self_bp = (gdbpy_breakpoint_object *) self;
511 
512   BPPY_REQUIRE_VALID (self_bp);
513 
514   return PyInt_FromLong (self_bp->bp->type);
515 }
516 
517 /* Python function to get the visibility of the breakpoint.  */
518 
519 static PyObject *
520 bppy_get_visibility (PyObject *self, void *closure)
521 {
522   gdbpy_breakpoint_object *self_bp = (gdbpy_breakpoint_object *) self;
523 
524   BPPY_REQUIRE_VALID (self_bp);
525 
526   if (self_bp->bp->number < 0)
527     Py_RETURN_FALSE;
528 
529   Py_RETURN_TRUE;
530 }
531 
532 /* Python function to determine if the breakpoint is a temporary
533    breakpoint.  */
534 
535 static PyObject *
536 bppy_get_temporary (PyObject *self, void *closure)
537 {
538   gdbpy_breakpoint_object *self_bp = (gdbpy_breakpoint_object *) self;
539 
540   BPPY_REQUIRE_VALID (self_bp);
541 
542   if (self_bp->bp->disposition == disp_del
543       || self_bp->bp->disposition == disp_del_at_next_stop)
544     Py_RETURN_TRUE;
545 
546   Py_RETURN_FALSE;
547 }
548 
549 /* Python function to get the breakpoint's number.  */
550 static PyObject *
551 bppy_get_number (PyObject *self, void *closure)
552 {
553   gdbpy_breakpoint_object *self_bp = (gdbpy_breakpoint_object *) self;
554 
555   BPPY_REQUIRE_VALID (self_bp);
556 
557   return PyInt_FromLong (self_bp->number);
558 }
559 
560 /* Python function to get the breakpoint's thread ID.  */
561 static PyObject *
562 bppy_get_thread (PyObject *self, void *closure)
563 {
564   gdbpy_breakpoint_object *self_bp = (gdbpy_breakpoint_object *) self;
565 
566   BPPY_REQUIRE_VALID (self_bp);
567 
568   if (self_bp->bp->thread == -1)
569     Py_RETURN_NONE;
570 
571   return PyInt_FromLong (self_bp->bp->thread);
572 }
573 
574 /* Python function to get the breakpoint's task ID (in Ada).  */
575 static PyObject *
576 bppy_get_task (PyObject *self, void *closure)
577 {
578   gdbpy_breakpoint_object *self_bp = (gdbpy_breakpoint_object *) self;
579 
580   BPPY_REQUIRE_VALID (self_bp);
581 
582   if (self_bp->bp->task == 0)
583     Py_RETURN_NONE;
584 
585   return PyInt_FromLong (self_bp->bp->task);
586 }
587 
588 /* Python function to get the breakpoint's hit count.  */
589 static PyObject *
590 bppy_get_hit_count (PyObject *self, void *closure)
591 {
592   gdbpy_breakpoint_object *self_bp = (gdbpy_breakpoint_object *) self;
593 
594   BPPY_REQUIRE_VALID (self_bp);
595 
596   return PyInt_FromLong (self_bp->bp->hit_count);
597 }
598 
599 /* Python function to get the breakpoint's ignore count.  */
600 static PyObject *
601 bppy_get_ignore_count (PyObject *self, void *closure)
602 {
603   gdbpy_breakpoint_object *self_bp = (gdbpy_breakpoint_object *) self;
604 
605   BPPY_REQUIRE_VALID (self_bp);
606 
607   return PyInt_FromLong (self_bp->bp->ignore_count);
608 }
609 
610 /* Python function to create a new breakpoint.  */
611 static int
612 bppy_init (PyObject *self, PyObject *args, PyObject *kwargs)
613 {
614   static char *keywords[] = { "spec", "type", "wp_class", "internal",
615 			      "temporary", NULL };
616   const char *spec;
617   int type = bp_breakpoint;
618   int access_type = hw_write;
619   PyObject *internal = NULL;
620   PyObject *temporary = NULL;
621   int internal_bp = 0;
622   int temporary_bp = 0;
623   volatile struct gdb_exception except;
624 
625   if (! PyArg_ParseTupleAndKeywords (args, kwargs, "s|iiOO", keywords,
626 				     &spec, &type, &access_type,
627 				     &internal, &temporary))
628     return -1;
629 
630   if (internal)
631     {
632       internal_bp = PyObject_IsTrue (internal);
633       if (internal_bp == -1)
634 	return -1;
635     }
636 
637   if (temporary != NULL)
638     {
639       temporary_bp = PyObject_IsTrue (temporary);
640       if (temporary_bp == -1)
641 	return -1;
642     }
643 
644   bppy_pending_object = (gdbpy_breakpoint_object *) self;
645   bppy_pending_object->number = -1;
646   bppy_pending_object->bp = NULL;
647 
648   TRY_CATCH (except, RETURN_MASK_ALL)
649     {
650       char *copy = xstrdup (spec);
651       struct cleanup *cleanup = make_cleanup (xfree, copy);
652 
653       switch (type)
654 	{
655 	case bp_breakpoint:
656 	  {
657 	    create_breakpoint (python_gdbarch,
658 			       copy, NULL, -1, NULL,
659 			       0,
660 			       temporary_bp, bp_breakpoint,
661 			       0,
662 			       AUTO_BOOLEAN_TRUE,
663 			       &bkpt_breakpoint_ops,
664 			       0, 1, internal_bp, 0);
665 	    break;
666 	  }
667         case bp_watchpoint:
668 	  {
669 	    if (access_type == hw_write)
670 	      watch_command_wrapper (copy, 0, internal_bp);
671 	    else if (access_type == hw_access)
672 	      awatch_command_wrapper (copy, 0, internal_bp);
673 	    else if (access_type == hw_read)
674 	      rwatch_command_wrapper (copy, 0, internal_bp);
675 	    else
676 	      error(_("Cannot understand watchpoint access type."));
677 	    break;
678 	  }
679 	default:
680 	  error(_("Do not understand breakpoint type to set."));
681 	}
682 
683       do_cleanups (cleanup);
684     }
685   if (except.reason < 0)
686     {
687       PyErr_Format (except.reason == RETURN_QUIT
688 		    ? PyExc_KeyboardInterrupt : PyExc_RuntimeError,
689 		    "%s", except.message);
690       return -1;
691     }
692 
693   BPPY_SET_REQUIRE_VALID ((gdbpy_breakpoint_object *) self);
694   return 0;
695 }
696 
697 
698 
699 static int
700 build_bp_list (struct breakpoint *b, void *arg)
701 {
702   PyObject *list = arg;
703   PyObject *bp = (PyObject *) b->py_bp_object;
704   int iserr = 0;
705 
706   /* Not all breakpoints will have a companion Python object.
707      Only breakpoints that were created via bppy_new, or
708      breakpoints that were created externally and are tracked by
709      the Python Scripting API.  */
710   if (bp)
711     iserr = PyList_Append (list, bp);
712 
713   if (iserr == -1)
714     return 1;
715 
716   return 0;
717 }
718 
719 /* Static function to return a tuple holding all breakpoints.  */
720 
721 PyObject *
722 gdbpy_breakpoints (PyObject *self, PyObject *args)
723 {
724   PyObject *list, *tuple;
725 
726   if (bppy_live == 0)
727     Py_RETURN_NONE;
728 
729   list = PyList_New (0);
730   if (!list)
731     return NULL;
732 
733   /* If iteratre_over_breakpoints returns non NULL it signals an error
734      condition.  In that case abandon building the list and return
735      NULL.  */
736   if (iterate_over_breakpoints (build_bp_list, list) != NULL)
737     {
738       Py_DECREF (list);
739       return NULL;
740     }
741 
742   tuple = PyList_AsTuple (list);
743   Py_DECREF (list);
744 
745   return tuple;
746 }
747 
748 /* Call the "stop" method (if implemented) in the breakpoint
749    class.  If the method returns True, the inferior  will be
750    stopped at the breakpoint.  Otherwise the inferior will be
751    allowed to continue.  */
752 
753 int
754 gdbpy_should_stop (struct gdbpy_breakpoint_object *bp_obj)
755 {
756   int stop = 1;
757 
758   PyObject *py_bp = (PyObject *) bp_obj;
759   struct breakpoint *b = bp_obj->bp;
760   struct gdbarch *garch = b->gdbarch ? b->gdbarch : get_current_arch ();
761   struct cleanup *cleanup = ensure_python_env (garch, current_language);
762 
763   if (bp_obj->is_finish_bp)
764     bpfinishpy_pre_stop_hook (bp_obj);
765 
766   if (PyObject_HasAttrString (py_bp, stop_func))
767     {
768       PyObject *result = PyObject_CallMethod (py_bp, stop_func, NULL);
769 
770       if (result)
771 	{
772 	  int evaluate = PyObject_IsTrue (result);
773 
774 	  if (evaluate == -1)
775 	    gdbpy_print_stack ();
776 
777 	  /* If the "stop" function returns False that means
778 	     the Python breakpoint wants GDB to continue.  */
779 	  if (! evaluate)
780 	    stop = 0;
781 
782 	  Py_DECREF (result);
783 	}
784       else
785 	gdbpy_print_stack ();
786     }
787 
788   if (bp_obj->is_finish_bp)
789     bpfinishpy_post_stop_hook (bp_obj);
790 
791   do_cleanups (cleanup);
792 
793   return stop;
794 }
795 
796 /* Checks if the  "stop" method exists in this breakpoint.
797    Used by condition_command to ensure mutual exclusion of breakpoint
798    conditions.  */
799 
800 int
801 gdbpy_breakpoint_has_py_cond (struct gdbpy_breakpoint_object *bp_obj)
802 {
803   int has_func = 0;
804   PyObject *py_bp = (PyObject *) bp_obj;
805   struct gdbarch *garch = bp_obj->bp->gdbarch ? bp_obj->bp->gdbarch :
806     get_current_arch ();
807   struct cleanup *cleanup = ensure_python_env (garch, current_language);
808 
809   if (py_bp != NULL)
810     has_func = PyObject_HasAttrString (py_bp, stop_func);
811 
812   do_cleanups (cleanup);
813 
814   return has_func;
815 }
816 
817 
818 
819 /* Event callback functions.  */
820 
821 /* Callback that is used when a breakpoint is created.  This function
822    will create a new Python breakpoint object.  */
823 static void
824 gdbpy_breakpoint_created (struct breakpoint *bp)
825 {
826   gdbpy_breakpoint_object *newbp;
827   PyGILState_STATE state;
828 
829   if (bp->number < 0 && bppy_pending_object == NULL)
830     return;
831 
832   if (bp->type != bp_breakpoint
833       && bp->type != bp_watchpoint
834       && bp->type != bp_hardware_watchpoint
835       && bp->type != bp_read_watchpoint
836       && bp->type != bp_access_watchpoint)
837     return;
838 
839   state = PyGILState_Ensure ();
840 
841   if (bppy_pending_object)
842     {
843       newbp = bppy_pending_object;
844       bppy_pending_object = NULL;
845     }
846   else
847     newbp = PyObject_New (gdbpy_breakpoint_object, &breakpoint_object_type);
848   if (newbp)
849     {
850       newbp->number = bp->number;
851       newbp->bp = bp;
852       newbp->bp->py_bp_object = newbp;
853       newbp->is_finish_bp = 0;
854       Py_INCREF (newbp);
855       ++bppy_live;
856     }
857   else
858     {
859       PyErr_SetString (PyExc_RuntimeError,
860 		       _("Error while creating breakpoint from GDB."));
861       gdbpy_print_stack ();
862     }
863 
864   PyGILState_Release (state);
865 }
866 
867 /* Callback that is used when a breakpoint is deleted.  This will
868    invalidate the corresponding Python object.  */
869 static void
870 gdbpy_breakpoint_deleted (struct breakpoint *b)
871 {
872   int num = b->number;
873   PyGILState_STATE state;
874   struct breakpoint *bp = NULL;
875   gdbpy_breakpoint_object *bp_obj;
876 
877   state = PyGILState_Ensure ();
878   bp = get_breakpoint (num);
879   if (bp)
880     {
881       bp_obj = bp->py_bp_object;
882       if (bp_obj)
883 	{
884 	  bp_obj->bp = NULL;
885 	  --bppy_live;
886 	  Py_DECREF (bp_obj);
887 	}
888     }
889   PyGILState_Release (state);
890 }
891 
892 
893 
894 /* Initialize the Python breakpoint code.  */
895 int
896 gdbpy_initialize_breakpoints (void)
897 {
898   int i;
899 
900   breakpoint_object_type.tp_new = PyType_GenericNew;
901   if (PyType_Ready (&breakpoint_object_type) < 0)
902     return -1;
903 
904   if (gdb_pymodule_addobject (gdb_module, "Breakpoint",
905 			      (PyObject *) &breakpoint_object_type) < 0)
906     return -1;
907 
908   observer_attach_breakpoint_created (gdbpy_breakpoint_created);
909   observer_attach_breakpoint_deleted (gdbpy_breakpoint_deleted);
910 
911   /* Add breakpoint types constants.  */
912   for (i = 0; pybp_codes[i].name; ++i)
913     {
914       if (PyModule_AddIntConstant (gdb_module,
915 				   /* Cast needed for Python 2.4.  */
916 				   (char *) pybp_codes[i].name,
917 				   pybp_codes[i].code) < 0)
918 	return -1;
919     }
920 
921   /* Add watchpoint types constants.  */
922   for (i = 0; pybp_watch_types[i].name; ++i)
923     {
924       if (PyModule_AddIntConstant (gdb_module,
925 				   /* Cast needed for Python 2.4.  */
926 				   (char *) pybp_watch_types[i].name,
927 				   pybp_watch_types[i].code) < 0)
928 	return -1;
929     }
930 
931   return 0;
932 }
933 
934 
935 
936 /* Helper function that overrides this Python object's
937    PyObject_GenericSetAttr to allow extra validation of the attribute
938    being set.  */
939 
940 static int
941 local_setattro (PyObject *self, PyObject *name, PyObject *v)
942 {
943   gdbpy_breakpoint_object *obj = (gdbpy_breakpoint_object *) self;
944   char *attr = python_string_to_host_string (name);
945 
946   if (attr == NULL)
947     return -1;
948 
949   /* If the attribute trying to be set is the "stop" method,
950      but we already have a condition set in the CLI, disallow this
951      operation.  */
952   if (strcmp (attr, stop_func) == 0 && obj->bp->cond_string)
953     {
954       xfree (attr);
955       PyErr_SetString (PyExc_RuntimeError,
956 		       _("Cannot set 'stop' method.  There is an " \
957 			 "existing GDB condition attached to the " \
958 			 "breakpoint."));
959       return -1;
960     }
961 
962   xfree (attr);
963 
964   return PyObject_GenericSetAttr ((PyObject *)self, name, v);
965 }
966 
967 static PyGetSetDef breakpoint_object_getset[] = {
968   { "enabled", bppy_get_enabled, bppy_set_enabled,
969     "Boolean telling whether the breakpoint is enabled.", NULL },
970   { "silent", bppy_get_silent, bppy_set_silent,
971     "Boolean telling whether the breakpoint is silent.", NULL },
972   { "thread", bppy_get_thread, bppy_set_thread,
973     "Thread ID for the breakpoint.\n\
974 If the value is a thread ID (integer), then this is a thread-specific breakpoint.\n\
975 If the value is None, then this breakpoint is not thread-specific.\n\
976 No other type of value can be used.", NULL },
977   { "task", bppy_get_task, bppy_set_task,
978     "Thread ID for the breakpoint.\n\
979 If the value is a task ID (integer), then this is an Ada task-specific breakpoint.\n\
980 If the value is None, then this breakpoint is not task-specific.\n\
981 No other type of value can be used.", NULL },
982   { "ignore_count", bppy_get_ignore_count, bppy_set_ignore_count,
983     "Number of times this breakpoint should be automatically continued.",
984     NULL },
985   { "number", bppy_get_number, NULL,
986     "Breakpoint's number assigned by GDB.", NULL },
987   { "hit_count", bppy_get_hit_count, bppy_set_hit_count,
988     "Number of times the breakpoint has been hit.\n\
989 Can be set to zero to clear the count. No other value is valid\n\
990 when setting this property.", NULL },
991   { "location", bppy_get_location, NULL,
992     "Location of the breakpoint, as specified by the user.", NULL},
993   { "expression", bppy_get_expression, NULL,
994     "Expression of the breakpoint, as specified by the user.", NULL},
995   { "condition", bppy_get_condition, bppy_set_condition,
996     "Condition of the breakpoint, as specified by the user,\
997 or None if no condition set."},
998   { "commands", bppy_get_commands, NULL,
999     "Commands of the breakpoint, as specified by the user."},
1000   { "type", bppy_get_type, NULL,
1001     "Type of breakpoint."},
1002   { "visible", bppy_get_visibility, NULL,
1003     "Whether the breakpoint is visible to the user."},
1004   { "temporary", bppy_get_temporary, NULL,
1005     "Whether this breakpoint is a temporary breakpoint."},
1006   { NULL }  /* Sentinel.  */
1007 };
1008 
1009 static PyMethodDef breakpoint_object_methods[] =
1010 {
1011   { "is_valid", bppy_is_valid, METH_NOARGS,
1012     "Return true if this breakpoint is valid, false if not." },
1013   { "delete", bppy_delete_breakpoint, METH_NOARGS,
1014     "Delete the underlying GDB breakpoint." },
1015   { NULL } /* Sentinel.  */
1016 };
1017 
1018 PyTypeObject breakpoint_object_type =
1019 {
1020   PyVarObject_HEAD_INIT (NULL, 0)
1021   "gdb.Breakpoint",		  /*tp_name*/
1022   sizeof (gdbpy_breakpoint_object), /*tp_basicsize*/
1023   0,				  /*tp_itemsize*/
1024   0,				  /*tp_dealloc*/
1025   0,				  /*tp_print*/
1026   0,				  /*tp_getattr*/
1027   0,				  /*tp_setattr*/
1028   0,				  /*tp_compare*/
1029   0,				  /*tp_repr*/
1030   0,				  /*tp_as_number*/
1031   0,				  /*tp_as_sequence*/
1032   0,				  /*tp_as_mapping*/
1033   0,				  /*tp_hash */
1034   0,				  /*tp_call*/
1035   0,				  /*tp_str*/
1036   0,				  /*tp_getattro*/
1037   (setattrofunc)local_setattro,   /*tp_setattro */
1038   0,				  /*tp_as_buffer*/
1039   Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE,  /*tp_flags*/
1040   "GDB breakpoint object",	  /* tp_doc */
1041   0,				  /* tp_traverse */
1042   0,				  /* tp_clear */
1043   0,				  /* tp_richcompare */
1044   0,				  /* tp_weaklistoffset */
1045   0,				  /* tp_iter */
1046   0,				  /* tp_iternext */
1047   breakpoint_object_methods,	  /* tp_methods */
1048   0,				  /* tp_members */
1049   breakpoint_object_getset,	  /* tp_getset */
1050   0,				  /* tp_base */
1051   0,				  /* tp_dict */
1052   0,				  /* tp_descr_get */
1053   0,				  /* tp_descr_set */
1054   0,				  /* tp_dictoffset */
1055   bppy_init,			  /* tp_init */
1056   0,				  /* tp_alloc */
1057 };
1058