xref: /netbsd-src/external/gpl3/gdb/dist/gdb/python/py-inferior.c (revision 212397c69a103ae7e5eafa8731ddfae671d2dee7)
1 /* Python interface to inferiors.
2 
3    Copyright (C) 2009-2015 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 "gdbcore.h"
22 #include "gdbthread.h"
23 #include "inferior.h"
24 #include "objfiles.h"
25 #include "observer.h"
26 #include "python-internal.h"
27 #include "arch-utils.h"
28 #include "language.h"
29 #include "gdb_signals.h"
30 #include "py-event.h"
31 #include "py-stopevent.h"
32 
33 struct threadlist_entry {
34   thread_object *thread_obj;
35   struct threadlist_entry *next;
36 };
37 
38 typedef struct
39 {
40   PyObject_HEAD
41 
42   /* The inferior we represent.  */
43   struct inferior *inferior;
44 
45   /* thread_object instances under this inferior.  This list owns a
46      reference to each object it contains.  */
47   struct threadlist_entry *threads;
48 
49   /* Number of threads in the list.  */
50   int nthreads;
51 } inferior_object;
52 
53 extern PyTypeObject inferior_object_type
54     CPYCHECKER_TYPE_OBJECT_FOR_TYPEDEF ("inferior_object");
55 
56 static const struct inferior_data *infpy_inf_data_key;
57 
58 typedef struct {
59   PyObject_HEAD
60   void *buffer;
61 
62   /* These are kept just for mbpy_str.  */
63   CORE_ADDR addr;
64   CORE_ADDR length;
65 } membuf_object;
66 
67 extern PyTypeObject membuf_object_type
68     CPYCHECKER_TYPE_OBJECT_FOR_TYPEDEF ("membuf_object");
69 
70 /* Require that INFERIOR be a valid inferior ID.  */
71 #define INFPY_REQUIRE_VALID(Inferior)				\
72   do {								\
73     if (!Inferior->inferior)					\
74       {								\
75 	PyErr_SetString (PyExc_RuntimeError,			\
76 			 _("Inferior no longer exists."));	\
77 	return NULL;						\
78       }								\
79   } while (0)
80 
81 static void
82 python_on_normal_stop (struct bpstats *bs, int print_frame)
83 {
84   struct cleanup *cleanup;
85   enum gdb_signal stop_signal;
86 
87   if (!gdb_python_initialized)
88     return;
89 
90   if (!find_thread_ptid (inferior_ptid))
91       return;
92 
93   stop_signal = inferior_thread ()->suspend.stop_signal;
94 
95   cleanup = ensure_python_env (get_current_arch (), current_language);
96 
97   if (emit_stop_event (bs, stop_signal) < 0)
98     gdbpy_print_stack ();
99 
100   do_cleanups (cleanup);
101 }
102 
103 static void
104 python_on_resume (ptid_t ptid)
105 {
106   struct cleanup *cleanup;
107 
108   if (!gdb_python_initialized)
109     return;
110 
111   cleanup = ensure_python_env (target_gdbarch (), current_language);
112 
113   if (emit_continue_event (ptid) < 0)
114     gdbpy_print_stack ();
115 
116   do_cleanups (cleanup);
117 }
118 
119 /* Callback, registered as an observer, that notifies Python listeners
120    when an inferior function call is about to be made. */
121 
122 static void
123 python_on_inferior_call_pre (ptid_t thread, CORE_ADDR address)
124 {
125   struct cleanup *cleanup;
126 
127   cleanup = ensure_python_env (target_gdbarch (), current_language);
128 
129   if (emit_inferior_call_event (INFERIOR_CALL_PRE, thread, address) < 0)
130     gdbpy_print_stack ();
131 
132   do_cleanups (cleanup);
133 }
134 
135 /* Callback, registered as an observer, that notifies Python listeners
136    when an inferior function call has completed. */
137 
138 static void
139 python_on_inferior_call_post (ptid_t thread, CORE_ADDR address)
140 {
141   struct cleanup *cleanup;
142 
143   cleanup = ensure_python_env (target_gdbarch (), current_language);
144 
145   if (emit_inferior_call_event (INFERIOR_CALL_POST, thread, address) < 0)
146     gdbpy_print_stack ();
147 
148   do_cleanups (cleanup);
149 }
150 
151 /* Callback, registered as an observer, that notifies Python listeners
152    when a part of memory has been modified by user action (eg via a
153    'set' command). */
154 
155 static void
156 python_on_memory_change (struct inferior *inferior, CORE_ADDR addr, ssize_t len, const bfd_byte *data)
157 {
158   struct cleanup *cleanup;
159 
160   cleanup = ensure_python_env (target_gdbarch (), current_language);
161 
162   if (emit_memory_changed_event (addr, len) < 0)
163     gdbpy_print_stack ();
164 
165   do_cleanups (cleanup);
166 }
167 
168 /* Callback, registered as an observer, that notifies Python listeners
169    when a register has been modified by user action (eg via a 'set'
170    command). */
171 
172 static void
173 python_on_register_change (struct frame_info *frame, int regnum)
174 {
175   struct cleanup *cleanup;
176 
177   cleanup = ensure_python_env (target_gdbarch (), current_language);
178 
179   if (emit_register_changed_event (frame, regnum) < 0)
180     gdbpy_print_stack ();
181 
182   do_cleanups (cleanup);
183 }
184 
185 static void
186 python_inferior_exit (struct inferior *inf)
187 {
188   struct cleanup *cleanup;
189   const LONGEST *exit_code = NULL;
190 
191   if (!gdb_python_initialized)
192     return;
193 
194   cleanup = ensure_python_env (target_gdbarch (), current_language);
195 
196   if (inf->has_exit_code)
197     exit_code = &inf->exit_code;
198 
199   if (emit_exited_event (exit_code, inf) < 0)
200     gdbpy_print_stack ();
201 
202   do_cleanups (cleanup);
203 }
204 
205 /* Callback used to notify Python listeners about new objfiles loaded in the
206    inferior.  OBJFILE may be NULL which means that the objfile list has been
207    cleared (emptied).  */
208 
209 static void
210 python_new_objfile (struct objfile *objfile)
211 {
212   struct cleanup *cleanup;
213 
214   if (!gdb_python_initialized)
215     return;
216 
217   cleanup = ensure_python_env (objfile != NULL
218 			       ? get_objfile_arch (objfile)
219 			       : target_gdbarch (),
220 			       current_language);
221 
222   if (objfile == NULL)
223     {
224       if (emit_clear_objfiles_event () < 0)
225 	gdbpy_print_stack ();
226     }
227   else
228     {
229       if (emit_new_objfile_event (objfile) < 0)
230 	gdbpy_print_stack ();
231     }
232 
233   do_cleanups (cleanup);
234 }
235 
236 /* Return a reference to the Python object of type Inferior
237    representing INFERIOR.  If the object has already been created,
238    return it and increment the reference count,  otherwise, create it.
239    Return NULL on failure.  */
240 PyObject *
241 inferior_to_inferior_object (struct inferior *inferior)
242 {
243   inferior_object *inf_obj;
244 
245   inf_obj = inferior_data (inferior, infpy_inf_data_key);
246   if (!inf_obj)
247     {
248       inf_obj = PyObject_New (inferior_object, &inferior_object_type);
249       if (!inf_obj)
250 	  return NULL;
251 
252       inf_obj->inferior = inferior;
253       inf_obj->threads = NULL;
254       inf_obj->nthreads = 0;
255 
256       set_inferior_data (inferior, infpy_inf_data_key, inf_obj);
257 
258     }
259   else
260     Py_INCREF ((PyObject *)inf_obj);
261 
262   return (PyObject *) inf_obj;
263 }
264 
265 /* Finds the Python Inferior object for the given PID.  Returns a
266    reference, or NULL if PID does not match any inferior object. */
267 
268 PyObject *
269 find_inferior_object (int pid)
270 {
271   struct inferior *inf = find_inferior_pid (pid);
272 
273   if (inf)
274     return inferior_to_inferior_object (inf);
275 
276   return NULL;
277 }
278 
279 thread_object *
280 find_thread_object (ptid_t ptid)
281 {
282   int pid;
283   struct threadlist_entry *thread;
284   PyObject *inf_obj;
285   thread_object *found = NULL;
286 
287   pid = ptid_get_pid (ptid);
288   if (pid == 0)
289     return NULL;
290 
291   inf_obj = find_inferior_object (pid);
292 
293   if (! inf_obj)
294     return NULL;
295 
296   for (thread = ((inferior_object *)inf_obj)->threads; thread;
297        thread = thread->next)
298     if (ptid_equal (thread->thread_obj->thread->ptid, ptid))
299       {
300 	found = thread->thread_obj;
301 	break;
302       }
303 
304   Py_DECREF (inf_obj);
305 
306   if (found)
307     return found;
308 
309   return NULL;
310 }
311 
312 static void
313 add_thread_object (struct thread_info *tp)
314 {
315   struct cleanup *cleanup;
316   thread_object *thread_obj;
317   inferior_object *inf_obj;
318   struct threadlist_entry *entry;
319 
320   if (!gdb_python_initialized)
321     return;
322 
323   cleanup = ensure_python_env (python_gdbarch, python_language);
324 
325   thread_obj = create_thread_object (tp);
326   if (!thread_obj)
327     {
328       gdbpy_print_stack ();
329       do_cleanups (cleanup);
330       return;
331     }
332 
333   inf_obj = (inferior_object *) thread_obj->inf_obj;
334 
335   entry = xmalloc (sizeof (struct threadlist_entry));
336   entry->thread_obj = thread_obj;
337   entry->next = inf_obj->threads;
338 
339   inf_obj->threads = entry;
340   inf_obj->nthreads++;
341 
342   do_cleanups (cleanup);
343 }
344 
345 static void
346 delete_thread_object (struct thread_info *tp, int ignore)
347 {
348   struct cleanup *cleanup;
349   inferior_object *inf_obj;
350   struct threadlist_entry **entry, *tmp;
351 
352   if (!gdb_python_initialized)
353     return;
354 
355   cleanup = ensure_python_env (python_gdbarch, python_language);
356 
357   inf_obj
358     = (inferior_object *) find_inferior_object (ptid_get_pid (tp->ptid));
359   if (!inf_obj)
360     {
361       do_cleanups (cleanup);
362       return;
363     }
364 
365   /* Find thread entry in its inferior's thread_list.  */
366   for (entry = &inf_obj->threads; *entry != NULL; entry =
367 	 &(*entry)->next)
368     if ((*entry)->thread_obj->thread == tp)
369       break;
370 
371   if (!*entry)
372     {
373       Py_DECREF (inf_obj);
374       do_cleanups (cleanup);
375       return;
376     }
377 
378   tmp = *entry;
379   tmp->thread_obj->thread = NULL;
380 
381   *entry = (*entry)->next;
382   inf_obj->nthreads--;
383 
384   Py_DECREF (tmp->thread_obj);
385   Py_DECREF (inf_obj);
386   xfree (tmp);
387 
388   do_cleanups (cleanup);
389 }
390 
391 static PyObject *
392 infpy_threads (PyObject *self, PyObject *args)
393 {
394   int i;
395   struct threadlist_entry *entry;
396   inferior_object *inf_obj = (inferior_object *) self;
397   PyObject *tuple;
398 
399   INFPY_REQUIRE_VALID (inf_obj);
400 
401   TRY
402     {
403       update_thread_list ();
404     }
405   CATCH (except, RETURN_MASK_ALL)
406     {
407       GDB_PY_HANDLE_EXCEPTION (except);
408     }
409   END_CATCH
410 
411   tuple = PyTuple_New (inf_obj->nthreads);
412   if (!tuple)
413     return NULL;
414 
415   for (i = 0, entry = inf_obj->threads; i < inf_obj->nthreads;
416        i++, entry = entry->next)
417     {
418       Py_INCREF (entry->thread_obj);
419       PyTuple_SET_ITEM (tuple, i, (PyObject *) entry->thread_obj);
420     }
421 
422   return tuple;
423 }
424 
425 static PyObject *
426 infpy_get_num (PyObject *self, void *closure)
427 {
428   inferior_object *inf = (inferior_object *) self;
429 
430   INFPY_REQUIRE_VALID (inf);
431 
432   return PyLong_FromLong (inf->inferior->num);
433 }
434 
435 static PyObject *
436 infpy_get_pid (PyObject *self, void *closure)
437 {
438   inferior_object *inf = (inferior_object *) self;
439 
440   INFPY_REQUIRE_VALID (inf);
441 
442   return PyLong_FromLong (inf->inferior->pid);
443 }
444 
445 static PyObject *
446 infpy_get_was_attached (PyObject *self, void *closure)
447 {
448   inferior_object *inf = (inferior_object *) self;
449 
450   INFPY_REQUIRE_VALID (inf);
451   if (inf->inferior->attach_flag)
452     Py_RETURN_TRUE;
453   Py_RETURN_FALSE;
454 }
455 
456 static int
457 build_inferior_list (struct inferior *inf, void *arg)
458 {
459   PyObject *list = arg;
460   PyObject *inferior = inferior_to_inferior_object (inf);
461   int success = 0;
462 
463   if (! inferior)
464     return 0;
465 
466   success = PyList_Append (list, inferior);
467   Py_DECREF (inferior);
468 
469   if (success)
470     return 1;
471 
472   return 0;
473 }
474 
475 /* Implementation of gdb.inferiors () -> (gdb.Inferior, ...).
476    Returns a tuple of all inferiors.  */
477 PyObject *
478 gdbpy_inferiors (PyObject *unused, PyObject *unused2)
479 {
480   PyObject *list, *tuple;
481 
482   list = PyList_New (0);
483   if (!list)
484     return NULL;
485 
486   if (iterate_over_inferiors (build_inferior_list, list))
487     {
488       Py_DECREF (list);
489       return NULL;
490     }
491 
492   tuple = PyList_AsTuple (list);
493   Py_DECREF (list);
494 
495   return tuple;
496 }
497 
498 /* Membuf and memory manipulation.  */
499 
500 /* Implementation of Inferior.read_memory (address, length).
501    Returns a Python buffer object with LENGTH bytes of the inferior's
502    memory at ADDRESS.  Both arguments are integers.  Returns NULL on error,
503    with a python exception set.  */
504 static PyObject *
505 infpy_read_memory (PyObject *self, PyObject *args, PyObject *kw)
506 {
507   CORE_ADDR addr, length;
508   void *buffer = NULL;
509   membuf_object *membuf_obj;
510   PyObject *addr_obj, *length_obj, *result;
511   static char *keywords[] = { "address", "length", NULL };
512 
513   if (! PyArg_ParseTupleAndKeywords (args, kw, "OO", keywords,
514 				     &addr_obj, &length_obj))
515     return NULL;
516 
517   if (get_addr_from_python (addr_obj, &addr) < 0
518       || get_addr_from_python (length_obj, &length) < 0)
519     return NULL;
520 
521   TRY
522     {
523       buffer = xmalloc (length);
524 
525       read_memory (addr, buffer, length);
526     }
527   CATCH (except, RETURN_MASK_ALL)
528     {
529       xfree (buffer);
530       GDB_PY_HANDLE_EXCEPTION (except);
531     }
532   END_CATCH
533 
534   membuf_obj = PyObject_New (membuf_object, &membuf_object_type);
535   if (membuf_obj == NULL)
536     {
537       xfree (buffer);
538       return NULL;
539     }
540 
541   membuf_obj->buffer = buffer;
542   membuf_obj->addr = addr;
543   membuf_obj->length = length;
544 
545 #ifdef IS_PY3K
546   result = PyMemoryView_FromObject ((PyObject *) membuf_obj);
547 #else
548   result = PyBuffer_FromReadWriteObject ((PyObject *) membuf_obj, 0,
549 					 Py_END_OF_BUFFER);
550 #endif
551   Py_DECREF (membuf_obj);
552 
553   return result;
554 }
555 
556 /* Implementation of Inferior.write_memory (address, buffer [, length]).
557    Writes the contents of BUFFER (a Python object supporting the read
558    buffer protocol) at ADDRESS in the inferior's memory.  Write LENGTH
559    bytes from BUFFER, or its entire contents if the argument is not
560    provided.  The function returns nothing.  Returns NULL on error, with
561    a python exception set.  */
562 static PyObject *
563 infpy_write_memory (PyObject *self, PyObject *args, PyObject *kw)
564 {
565   struct gdb_exception except = exception_none;
566   Py_ssize_t buf_len;
567   const char *buffer;
568   CORE_ADDR addr, length;
569   PyObject *addr_obj, *length_obj = NULL;
570   static char *keywords[] = { "address", "buffer", "length", NULL };
571 #ifdef IS_PY3K
572   Py_buffer pybuf;
573 
574   if (! PyArg_ParseTupleAndKeywords (args, kw, "Os*|O", keywords,
575 				     &addr_obj, &pybuf,
576 				     &length_obj))
577     return NULL;
578 
579   buffer = pybuf.buf;
580   buf_len = pybuf.len;
581 #else
582   if (! PyArg_ParseTupleAndKeywords (args, kw, "Os#|O", keywords,
583 				     &addr_obj, &buffer, &buf_len,
584 				     &length_obj))
585     return NULL;
586 #endif
587 
588   if (get_addr_from_python (addr_obj, &addr) < 0)
589     goto fail;
590 
591   if (!length_obj)
592     length = buf_len;
593   else if (get_addr_from_python (length_obj, &length) < 0)
594     goto fail;
595 
596   TRY
597     {
598       write_memory_with_notification (addr, (gdb_byte *) buffer, length);
599     }
600   CATCH (ex, RETURN_MASK_ALL)
601     {
602       except = ex;
603     }
604   END_CATCH
605 
606 #ifdef IS_PY3K
607   PyBuffer_Release (&pybuf);
608 #endif
609   GDB_PY_HANDLE_EXCEPTION (except);
610 
611   Py_RETURN_NONE;
612 
613  fail:
614 #ifdef IS_PY3K
615   PyBuffer_Release (&pybuf);
616 #endif
617   return NULL;
618 }
619 
620 /* Destructor of Membuf objects.  */
621 static void
622 mbpy_dealloc (PyObject *self)
623 {
624   xfree (((membuf_object *) self)->buffer);
625   Py_TYPE (self)->tp_free (self);
626 }
627 
628 /* Return a description of the Membuf object.  */
629 static PyObject *
630 mbpy_str (PyObject *self)
631 {
632   membuf_object *membuf_obj = (membuf_object *) self;
633 
634   return PyString_FromFormat (_("Memory buffer for address %s, \
635 which is %s bytes long."),
636 			      paddress (python_gdbarch, membuf_obj->addr),
637 			      pulongest (membuf_obj->length));
638 }
639 
640 #ifdef IS_PY3K
641 
642 static int
643 get_buffer (PyObject *self, Py_buffer *buf, int flags)
644 {
645   membuf_object *membuf_obj = (membuf_object *) self;
646   int ret;
647 
648   ret = PyBuffer_FillInfo (buf, self, membuf_obj->buffer,
649 			   membuf_obj->length, 0,
650 			   PyBUF_CONTIG);
651   buf->format = "c";
652 
653   return ret;
654 }
655 
656 #else
657 
658 static Py_ssize_t
659 get_read_buffer (PyObject *self, Py_ssize_t segment, void **ptrptr)
660 {
661   membuf_object *membuf_obj = (membuf_object *) self;
662 
663   if (segment)
664     {
665       PyErr_SetString (PyExc_SystemError,
666 		       _("The memory buffer supports only one segment."));
667       return -1;
668     }
669 
670   *ptrptr = membuf_obj->buffer;
671 
672   return membuf_obj->length;
673 }
674 
675 static Py_ssize_t
676 get_write_buffer (PyObject *self, Py_ssize_t segment, void **ptrptr)
677 {
678   return get_read_buffer (self, segment, ptrptr);
679 }
680 
681 static Py_ssize_t
682 get_seg_count (PyObject *self, Py_ssize_t *lenp)
683 {
684   if (lenp)
685     *lenp = ((membuf_object *) self)->length;
686 
687   return 1;
688 }
689 
690 static Py_ssize_t
691 get_char_buffer (PyObject *self, Py_ssize_t segment, char **ptrptr)
692 {
693   void *ptr = NULL;
694   Py_ssize_t ret;
695 
696   ret = get_read_buffer (self, segment, &ptr);
697   *ptrptr = (char *) ptr;
698 
699   return ret;
700 }
701 
702 #endif	/* IS_PY3K */
703 
704 /* Implementation of
705    gdb.search_memory (address, length, pattern).  ADDRESS is the
706    address to start the search.  LENGTH specifies the scope of the
707    search from ADDRESS.  PATTERN is the pattern to search for (and
708    must be a Python object supporting the buffer protocol).
709    Returns a Python Long object holding the address where the pattern
710    was located, or if the pattern was not found, returns None.  Returns NULL
711    on error, with a python exception set.  */
712 static PyObject *
713 infpy_search_memory (PyObject *self, PyObject *args, PyObject *kw)
714 {
715   struct gdb_exception except = exception_none;
716   CORE_ADDR start_addr, length;
717   static char *keywords[] = { "address", "length", "pattern", NULL };
718   PyObject *start_addr_obj, *length_obj;
719   Py_ssize_t pattern_size;
720   const void *buffer;
721   CORE_ADDR found_addr;
722   int found = 0;
723 #ifdef IS_PY3K
724   Py_buffer pybuf;
725 
726   if (! PyArg_ParseTupleAndKeywords (args, kw, "OOs*", keywords,
727 				     &start_addr_obj, &length_obj,
728 				     &pybuf))
729     return NULL;
730 
731   buffer = pybuf.buf;
732   pattern_size = pybuf.len;
733 #else
734   PyObject *pattern;
735 
736   if (! PyArg_ParseTupleAndKeywords (args, kw, "OOO", keywords,
737  				     &start_addr_obj, &length_obj,
738 				     &pattern))
739      return NULL;
740 
741   if (!PyObject_CheckReadBuffer (pattern))
742     {
743       PyErr_SetString (PyExc_RuntimeError,
744 		       _("The pattern is not a Python buffer."));
745 
746       return NULL;
747     }
748 
749   if (PyObject_AsReadBuffer (pattern, &buffer, &pattern_size) == -1)
750     return NULL;
751 #endif
752 
753   if (get_addr_from_python (start_addr_obj, &start_addr) < 0)
754     goto fail;
755 
756   if (get_addr_from_python (length_obj, &length) < 0)
757     goto fail;
758 
759   if (!length)
760     {
761       PyErr_SetString (PyExc_ValueError,
762 		       _("Search range is empty."));
763       goto fail;
764     }
765   /* Watch for overflows.  */
766   else if (length > CORE_ADDR_MAX
767 	   || (start_addr + length - 1) < start_addr)
768     {
769       PyErr_SetString (PyExc_ValueError,
770 		       _("The search range is too large."));
771       goto fail;
772     }
773 
774   TRY
775     {
776       found = target_search_memory (start_addr, length,
777 				    buffer, pattern_size,
778 				    &found_addr);
779     }
780   CATCH (ex, RETURN_MASK_ALL)
781     {
782       except = ex;
783     }
784   END_CATCH
785 
786 #ifdef IS_PY3K
787   PyBuffer_Release (&pybuf);
788 #endif
789   GDB_PY_HANDLE_EXCEPTION (except);
790 
791   if (found)
792     return PyLong_FromLong (found_addr);
793   else
794     Py_RETURN_NONE;
795 
796  fail:
797 #ifdef IS_PY3K
798   PyBuffer_Release (&pybuf);
799 #endif
800   return NULL;
801 }
802 
803 /* Implementation of gdb.Inferior.is_valid (self) -> Boolean.
804    Returns True if this inferior object still exists in GDB.  */
805 
806 static PyObject *
807 infpy_is_valid (PyObject *self, PyObject *args)
808 {
809   inferior_object *inf = (inferior_object *) self;
810 
811   if (! inf->inferior)
812     Py_RETURN_FALSE;
813 
814   Py_RETURN_TRUE;
815 }
816 
817 static void
818 infpy_dealloc (PyObject *obj)
819 {
820   inferior_object *inf_obj = (inferior_object *) obj;
821   struct inferior *inf = inf_obj->inferior;
822 
823   if (! inf)
824     return;
825 
826   set_inferior_data (inf, infpy_inf_data_key, NULL);
827 }
828 
829 /* Clear the INFERIOR pointer in an Inferior object and clear the
830    thread list.  */
831 static void
832 py_free_inferior (struct inferior *inf, void *datum)
833 {
834 
835   struct cleanup *cleanup;
836   inferior_object *inf_obj = datum;
837   struct threadlist_entry *th_entry, *th_tmp;
838 
839   if (!gdb_python_initialized)
840     return;
841 
842   cleanup = ensure_python_env (python_gdbarch, python_language);
843 
844   inf_obj->inferior = NULL;
845 
846   /* Deallocate threads list.  */
847   for (th_entry = inf_obj->threads; th_entry != NULL;)
848     {
849       Py_DECREF (th_entry->thread_obj);
850 
851       th_tmp = th_entry;
852       th_entry = th_entry->next;
853       xfree (th_tmp);
854     }
855 
856   inf_obj->nthreads = 0;
857 
858   Py_DECREF ((PyObject *) inf_obj);
859   do_cleanups (cleanup);
860 }
861 
862 /* Implementation of gdb.selected_inferior() -> gdb.Inferior.
863    Returns the current inferior object.  */
864 
865 PyObject *
866 gdbpy_selected_inferior (PyObject *self, PyObject *args)
867 {
868   return inferior_to_inferior_object (current_inferior ());
869 }
870 
871 int
872 gdbpy_initialize_inferior (void)
873 {
874   if (PyType_Ready (&inferior_object_type) < 0)
875     return -1;
876 
877   if (gdb_pymodule_addobject (gdb_module, "Inferior",
878 			      (PyObject *) &inferior_object_type) < 0)
879     return -1;
880 
881   infpy_inf_data_key =
882     register_inferior_data_with_cleanup (NULL, py_free_inferior);
883 
884   observer_attach_new_thread (add_thread_object);
885   observer_attach_thread_exit (delete_thread_object);
886   observer_attach_normal_stop (python_on_normal_stop);
887   observer_attach_target_resumed (python_on_resume);
888   observer_attach_inferior_call_pre (python_on_inferior_call_pre);
889   observer_attach_inferior_call_post (python_on_inferior_call_post);
890   observer_attach_memory_changed (python_on_memory_change);
891   observer_attach_register_changed (python_on_register_change);
892   observer_attach_inferior_exit (python_inferior_exit);
893   observer_attach_new_objfile (python_new_objfile);
894 
895   membuf_object_type.tp_new = PyType_GenericNew;
896   if (PyType_Ready (&membuf_object_type) < 0)
897     return -1;
898 
899   return gdb_pymodule_addobject (gdb_module, "Membuf", (PyObject *)
900 				 &membuf_object_type);
901 }
902 
903 static PyGetSetDef inferior_object_getset[] =
904 {
905   { "num", infpy_get_num, NULL, "ID of inferior, as assigned by GDB.", NULL },
906   { "pid", infpy_get_pid, NULL, "PID of inferior, as assigned by the OS.",
907     NULL },
908   { "was_attached", infpy_get_was_attached, NULL,
909     "True if the inferior was created using 'attach'.", NULL },
910   { NULL }
911 };
912 
913 static PyMethodDef inferior_object_methods[] =
914 {
915   { "is_valid", infpy_is_valid, METH_NOARGS,
916     "is_valid () -> Boolean.\n\
917 Return true if this inferior is valid, false if not." },
918   { "threads", infpy_threads, METH_NOARGS,
919     "Return all the threads of this inferior." },
920   { "read_memory", (PyCFunction) infpy_read_memory,
921     METH_VARARGS | METH_KEYWORDS,
922     "read_memory (address, length) -> buffer\n\
923 Return a buffer object for reading from the inferior's memory." },
924   { "write_memory", (PyCFunction) infpy_write_memory,
925     METH_VARARGS | METH_KEYWORDS,
926     "write_memory (address, buffer [, length])\n\
927 Write the given buffer object to the inferior's memory." },
928   { "search_memory", (PyCFunction) infpy_search_memory,
929     METH_VARARGS | METH_KEYWORDS,
930     "search_memory (address, length, pattern) -> long\n\
931 Return a long with the address of a match, or None." },
932   { NULL }
933 };
934 
935 PyTypeObject inferior_object_type =
936 {
937   PyVarObject_HEAD_INIT (NULL, 0)
938   "gdb.Inferior",		  /* tp_name */
939   sizeof (inferior_object),	  /* tp_basicsize */
940   0,				  /* tp_itemsize */
941   infpy_dealloc,		  /* tp_dealloc */
942   0,				  /* tp_print */
943   0,				  /* tp_getattr */
944   0,				  /* tp_setattr */
945   0,				  /* tp_compare */
946   0,				  /* tp_repr */
947   0,				  /* tp_as_number */
948   0,				  /* tp_as_sequence */
949   0,				  /* tp_as_mapping */
950   0,				  /* tp_hash  */
951   0,				  /* tp_call */
952   0,				  /* tp_str */
953   0,				  /* tp_getattro */
954   0,				  /* tp_setattro */
955   0,				  /* tp_as_buffer */
956   Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_ITER,  /* tp_flags */
957   "GDB inferior object",	  /* tp_doc */
958   0,				  /* tp_traverse */
959   0,				  /* tp_clear */
960   0,				  /* tp_richcompare */
961   0,				  /* tp_weaklistoffset */
962   0,				  /* tp_iter */
963   0,				  /* tp_iternext */
964   inferior_object_methods,	  /* tp_methods */
965   0,				  /* tp_members */
966   inferior_object_getset,	  /* tp_getset */
967   0,				  /* tp_base */
968   0,				  /* tp_dict */
969   0,				  /* tp_descr_get */
970   0,				  /* tp_descr_set */
971   0,				  /* tp_dictoffset */
972   0,				  /* tp_init */
973   0				  /* tp_alloc */
974 };
975 
976 #ifdef IS_PY3K
977 
978 static PyBufferProcs buffer_procs =
979 {
980   get_buffer
981 };
982 
983 #else
984 
985 /* Python doesn't provide a decent way to get compatibility here.  */
986 #if HAVE_LIBPYTHON2_4
987 #define CHARBUFFERPROC_NAME getcharbufferproc
988 #else
989 #define CHARBUFFERPROC_NAME charbufferproc
990 #endif
991 
992 static PyBufferProcs buffer_procs = {
993   get_read_buffer,
994   get_write_buffer,
995   get_seg_count,
996   /* The cast here works around a difference between Python 2.4 and
997      Python 2.5.  */
998   (CHARBUFFERPROC_NAME) get_char_buffer
999 };
1000 #endif	/* IS_PY3K */
1001 
1002 PyTypeObject membuf_object_type = {
1003   PyVarObject_HEAD_INIT (NULL, 0)
1004   "gdb.Membuf",			  /*tp_name*/
1005   sizeof (membuf_object),	  /*tp_basicsize*/
1006   0,				  /*tp_itemsize*/
1007   mbpy_dealloc,			  /*tp_dealloc*/
1008   0,				  /*tp_print*/
1009   0,				  /*tp_getattr*/
1010   0,				  /*tp_setattr*/
1011   0,				  /*tp_compare*/
1012   0,				  /*tp_repr*/
1013   0,				  /*tp_as_number*/
1014   0,				  /*tp_as_sequence*/
1015   0,				  /*tp_as_mapping*/
1016   0,				  /*tp_hash */
1017   0,				  /*tp_call*/
1018   mbpy_str,			  /*tp_str*/
1019   0,				  /*tp_getattro*/
1020   0,				  /*tp_setattro*/
1021   &buffer_procs,		  /*tp_as_buffer*/
1022   Py_TPFLAGS_DEFAULT,		  /*tp_flags*/
1023   "GDB memory buffer object", 	  /*tp_doc*/
1024   0,				  /* tp_traverse */
1025   0,				  /* tp_clear */
1026   0,				  /* tp_richcompare */
1027   0,				  /* tp_weaklistoffset */
1028   0,				  /* tp_iter */
1029   0,				  /* tp_iternext */
1030   0,				  /* tp_methods */
1031   0,				  /* tp_members */
1032   0,				  /* tp_getset */
1033   0,				  /* tp_base */
1034   0,				  /* tp_dict */
1035   0,				  /* tp_descr_get */
1036   0,				  /* tp_descr_set */
1037   0,				  /* tp_dictoffset */
1038   0,				  /* tp_init */
1039   0,				  /* tp_alloc */
1040 };
1041