xref: /netbsd-src/external/gpl3/gdb.old/dist/gdb/python/py-linetable.c (revision 479d8f7d843cc1b22d497efdf1f27a50ee8418d4)
1 /* Python interface to line tables.
2 
3    Copyright (C) 2013-2015 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 "python-internal.h"
22 
23 typedef struct {
24   PyObject_HEAD
25   /* The line table source line.  */
26   int line;
27   /* The pc associated with the source line.  */
28   CORE_ADDR pc;
29 } linetable_entry_object;
30 
31 extern PyTypeObject linetable_entry_object_type
32     CPYCHECKER_TYPE_OBJECT_FOR_TYPEDEF ("linetable_entry_object");
33 
34 typedef struct {
35   PyObject_HEAD
36   /* The symtab python object.  We store the Python object here as the
37      underlying symtab can become invalid, and we have to run validity
38      checks on it.  */
39   PyObject *symtab;
40 } linetable_object;
41 
42 extern PyTypeObject linetable_object_type
43     CPYCHECKER_TYPE_OBJECT_FOR_TYPEDEF ("linetable_object");
44 
45 typedef struct {
46   PyObject_HEAD
47   /* The current entry in the line table for the iterator  */
48   int current_index;
49   /* Pointer back to the original source line table object.  Needed to
50      check if the line table is still valid, and has not been invalidated
51      when an object file has been freed.  */
52   PyObject *source;
53 } ltpy_iterator_object;
54 
55 extern PyTypeObject ltpy_iterator_object_type
56     CPYCHECKER_TYPE_OBJECT_FOR_TYPEDEF ("ltpy_iterator_object");
57 
58 /* Internal helper function to extract gdb.Symtab from a gdb.Linetable
59    object.  */
60 
61 static PyObject *
62 get_symtab (PyObject *linetable)
63 {
64   linetable_object *lt = (linetable_object *) linetable;
65 
66   return lt->symtab;
67 }
68 
69 #define LTPY_REQUIRE_VALID(lt_obj, symtab)				\
70   do {									\
71     symtab = symtab_object_to_symtab (get_symtab (lt_obj));		\
72     if (symtab == NULL)							\
73       {									\
74 	  PyErr_SetString (PyExc_RuntimeError,				\
75 			   _("Symbol Table in line table is invalid."));\
76 	  return NULL;							\
77 	}								\
78   } while (0)
79 
80 
81 /* Helper function to create a line table object that wraps a
82    gdb.Symtab object.  */
83 
84 PyObject *
85 symtab_to_linetable_object (PyObject *symtab)
86 {
87   linetable_object *ltable;
88 
89   ltable = PyObject_New (linetable_object, &linetable_object_type);
90   if (ltable != NULL)
91     {
92       ltable->symtab = symtab;
93       Py_INCREF (symtab);
94     }
95   return (PyObject *) ltable;
96 }
97 
98 /* Internal helper function to build a line table object from a line
99    and an address.  */
100 
101 static PyObject *
102 build_linetable_entry (int line, CORE_ADDR address)
103 {
104   linetable_entry_object *obj;
105 
106   obj = PyObject_New (linetable_entry_object,
107 		      &linetable_entry_object_type);
108   if (obj != NULL)
109     {
110       obj->line = line;
111       obj->pc = address;
112     }
113 
114   return (PyObject *) obj;
115 }
116 
117 /* Internal helper function to build a Python Tuple from a GDB Vector.
118    A line table entry can have multiple PCs for a given source line.
119    Construct a Tuple of all entries for the given source line, LINE
120    from the line table VEC.  Construct one line table entry object per
121    address.  */
122 
123 static PyObject *
124 build_line_table_tuple_from_pcs (int line, VEC (CORE_ADDR) *vec)
125 {
126   int vec_len = 0;
127   PyObject *tuple;
128   CORE_ADDR pc;
129   int i;
130 
131   vec_len = VEC_length (CORE_ADDR, vec);
132   if (vec_len < 1)
133     Py_RETURN_NONE;
134 
135   tuple = PyTuple_New (vec_len);
136 
137   if (tuple == NULL)
138     return NULL;
139 
140   for (i = 0; VEC_iterate (CORE_ADDR, vec, i, pc); ++i)
141     {
142       PyObject *obj = build_linetable_entry (line, pc);
143 
144       if (obj == NULL)
145 	{
146 	  Py_DECREF (tuple);
147 	  tuple = NULL;
148 	  break;
149 	}
150       else if (PyTuple_SetItem (tuple, i, obj) != 0)
151 	{
152 	  Py_DECREF (obj);
153 	  Py_DECREF (tuple);
154 	  tuple = NULL;
155 	  break;
156 	}
157     }
158 
159   return tuple;
160 }
161 
162 /* Implementation of gdb.LineTable.line (self) -> Tuple.  Returns a
163    tuple of LineTableEntry objects associated with this line from the
164    in the line table.  */
165 
166 static PyObject *
167 ltpy_get_pcs_for_line (PyObject *self, PyObject *args)
168 {
169   struct symtab *symtab;
170   gdb_py_longest py_line;
171   struct linetable_entry *best_entry = NULL;
172   linetable_entry_object *result;
173   VEC (CORE_ADDR) *pcs = NULL;
174   PyObject *tuple;
175 
176   LTPY_REQUIRE_VALID (self, symtab);
177 
178   if (! PyArg_ParseTuple (args, GDB_PY_LL_ARG, &py_line))
179     return NULL;
180 
181   TRY
182     {
183       pcs = find_pcs_for_symtab_line (symtab, py_line, &best_entry);
184     }
185   CATCH (except, RETURN_MASK_ALL)
186     {
187       GDB_PY_HANDLE_EXCEPTION (except);
188     }
189   END_CATCH
190 
191   tuple = build_line_table_tuple_from_pcs (py_line, pcs);
192   VEC_free (CORE_ADDR, pcs);
193 
194   return tuple;
195 }
196 
197 /* Implementation of gdb.LineTable.has_line (self, line) -> Boolean.
198    Returns a Python Boolean indicating whether a source line has any
199    line table entries corresponding to it.  */
200 
201 static PyObject *
202 ltpy_has_line (PyObject *self, PyObject *args)
203 {
204   struct symtab *symtab;
205   gdb_py_longest py_line;
206   int index;
207 
208   LTPY_REQUIRE_VALID (self, symtab);
209 
210   if (! PyArg_ParseTuple (args, GDB_PY_LL_ARG, &py_line))
211     return NULL;
212 
213   if (SYMTAB_LINETABLE (symtab) == NULL)
214     {
215       PyErr_SetString (PyExc_RuntimeError,
216 		       _("Linetable information not found in symbol table"));
217       return NULL;
218     }
219 
220   for (index = 0; index < SYMTAB_LINETABLE (symtab)->nitems; index++)
221     {
222       struct linetable_entry *item = &(SYMTAB_LINETABLE (symtab)->item[index]);
223       if (item->line == py_line)
224 	  Py_RETURN_TRUE;
225     }
226 
227   Py_RETURN_FALSE;
228 }
229 
230 /* Implementation of gdb.LineTable.source_lines (self) -> FrozenSet.
231    Returns a Python FrozenSet that contains source line entries in the
232    line table.  This function will just return the source lines
233    without corresponding addresses.  */
234 
235 static PyObject *
236 ltpy_get_all_source_lines (PyObject *self, PyObject *args)
237 {
238   struct symtab *symtab;
239   Py_ssize_t index;
240   PyObject *source_list, *source_dict, *line;
241   struct linetable_entry *item;
242   Py_ssize_t list_size;
243 
244   LTPY_REQUIRE_VALID (self, symtab);
245 
246   if (SYMTAB_LINETABLE (symtab) == NULL)
247     {
248       PyErr_SetString (PyExc_RuntimeError,
249 		       _("Linetable information not found in symbol table"));
250       return NULL;
251     }
252 
253   source_dict = PyDict_New ();
254   if (source_dict == NULL)
255     return NULL;
256 
257   for (index = 0; index < SYMTAB_LINETABLE (symtab)->nitems; index++)
258     {
259       item = &(SYMTAB_LINETABLE (symtab)->item[index]);
260 
261       /* 0 is used to signify end of line table information.  Do not
262 	 include in the source set. */
263       if (item->line > 0)
264 	{
265 	  line = gdb_py_object_from_longest (item->line);
266 
267 	  if (line == NULL)
268 	    {
269 	      Py_DECREF (source_dict);
270 	      return NULL;
271 	    }
272 
273 	  if (PyDict_SetItem (source_dict, line, Py_None) == -1)
274 	    {
275 	      Py_DECREF (line);
276 	      Py_DECREF (source_dict);
277 	      return NULL;
278 	    }
279 
280 	  Py_DECREF (line);
281 	}
282     }
283 
284 
285   source_list = PyDict_Keys (source_dict);
286   Py_DECREF (source_dict);
287 
288   return source_list;
289 }
290 
291 /* Implementation of gdb.Linetable.is_valid (self) -> Boolean.
292    Returns True if this line table object still exists in GDB.  */
293 
294 static PyObject *
295 ltpy_is_valid (PyObject *self, PyObject *args)
296 {
297   struct symtab *symtab = NULL;
298   linetable_object *obj = (linetable_object *) self;
299 
300   symtab = symtab_object_to_symtab (get_symtab (self));
301 
302   if (symtab == NULL)
303     Py_RETURN_FALSE;
304 
305   Py_RETURN_TRUE;
306 }
307 
308 /* Deconstructor for the line table object.  Decrement the reference
309    to the symbol table object before calling the default free.  */
310 
311 static void
312 ltpy_dealloc (PyObject *self)
313 {
314   linetable_object *obj = (linetable_object *) self;
315 
316   Py_DECREF (obj->symtab);
317   Py_TYPE (self)->tp_free (self);
318 }
319 
320 /* Initialize LineTable, LineTableEntry and LineTableIterator
321    objects.  */
322 
323 int
324 gdbpy_initialize_linetable (void)
325 {
326   if (PyType_Ready (&linetable_object_type) < 0)
327     return -1;
328   if (PyType_Ready (&linetable_entry_object_type) < 0)
329     return -1;
330   if (PyType_Ready (&ltpy_iterator_object_type) < 0)
331     return -1;
332 
333   Py_INCREF (&linetable_object_type);
334   Py_INCREF (&linetable_entry_object_type);
335   Py_INCREF (&ltpy_iterator_object_type);
336 
337   if (gdb_pymodule_addobject (gdb_module, "LineTable",
338 			      (PyObject *) &linetable_object_type) < 0)
339     return -1;
340 
341   if (gdb_pymodule_addobject (gdb_module, "LineTableEntry",
342 			      (PyObject *) &linetable_entry_object_type) < 0)
343     return -1;
344 
345   if (gdb_pymodule_addobject (gdb_module, "LineTableIterator",
346 			      (PyObject *) &ltpy_iterator_object_type) < 0)
347     return -1;
348 
349   return 0;
350 }
351 
352 /* Linetable entry object get functions.  */
353 
354 /* Implementation of gdb.LineTableEntry.line (self) -> Long.  Returns
355    a long integer associated with the line table entry.  */
356 
357 static PyObject *
358 ltpy_entry_get_line (PyObject *self, void *closure)
359 {
360   linetable_entry_object *obj = (linetable_entry_object *) self;
361 
362   return gdb_py_object_from_longest (obj->line);
363 }
364 
365 /* Implementation of gdb.LineTableEntry.pc (self) -> Long.  Returns a
366    a long integer associated with the PC of the line table entry.  */
367 
368 static PyObject *
369 ltpy_entry_get_pc (PyObject *self, void *closure)
370 {
371   linetable_entry_object *obj = (linetable_entry_object *) self;
372 
373   return  gdb_py_object_from_longest (obj->pc);
374 }
375 
376 /* Linetable iterator functions.  */
377 
378 /* Return a new line table iterator.  */
379 
380 static PyObject *
381 ltpy_iter (PyObject *self)
382 {
383   ltpy_iterator_object *ltpy_iter_obj;
384   struct symtab *symtab = NULL;
385 
386   LTPY_REQUIRE_VALID (self, symtab);
387 
388   ltpy_iter_obj = PyObject_New (ltpy_iterator_object,
389 				&ltpy_iterator_object_type);
390   if (ltpy_iter_obj == NULL)
391     return NULL;
392 
393   ltpy_iter_obj->current_index = 0;
394   ltpy_iter_obj->source = self;
395 
396   Py_INCREF (self);
397   return (PyObject *) ltpy_iter_obj;
398 }
399 
400 static void
401 ltpy_iterator_dealloc (PyObject *obj)
402 {
403   ltpy_iterator_object *iter_obj = (ltpy_iterator_object *) obj;
404 
405   Py_DECREF (iter_obj->source);
406 }
407 
408 /* Return a reference to the line table iterator.  */
409 
410 static PyObject *
411 ltpy_iterator (PyObject *self)
412 {
413   ltpy_iterator_object *iter_obj = (ltpy_iterator_object *) self;
414   struct symtab *symtab;
415 
416   LTPY_REQUIRE_VALID (iter_obj->source, symtab);
417 
418   Py_INCREF (self);
419   return self;
420 }
421 
422 /* Return the next line table entry in the iteration through the line
423    table data structure.  */
424 
425 static PyObject *
426 ltpy_iternext (PyObject *self)
427 {
428   ltpy_iterator_object *iter_obj = (ltpy_iterator_object *) self;
429   struct symtab *symtab;
430   int index;
431   PyObject *obj;
432   struct linetable_entry *item;
433 
434   LTPY_REQUIRE_VALID (iter_obj->source, symtab);
435 
436   if (iter_obj->current_index >= SYMTAB_LINETABLE (symtab)->nitems)
437     goto stop_iteration;
438 
439   item = &(SYMTAB_LINETABLE (symtab)->item[iter_obj->current_index]);
440 
441   /* Skip over internal entries such as 0.  0 signifies the end of
442      line table data and is not useful to the API user.  */
443   while (item->line < 1)
444     {
445       iter_obj->current_index++;
446 
447       /* Exit if the internal value is the last item in the line table.  */
448       if (iter_obj->current_index >= SYMTAB_LINETABLE (symtab)->nitems)
449 	goto stop_iteration;
450       item = &(SYMTAB_LINETABLE (symtab)->item[iter_obj->current_index]);
451     }
452 
453   obj = build_linetable_entry (item->line, item->pc);
454   iter_obj->current_index++;
455 
456   return obj;
457 
458  stop_iteration:
459   PyErr_SetNone (PyExc_StopIteration);
460   return NULL;
461 }
462 
463 /* Implementation of gdb.LinetableIterator.is_valid (self) -> Boolean.
464    Returns True if this line table iterator object still exists in
465    GDB.  */
466 
467 static PyObject *
468 ltpy_iter_is_valid (PyObject *self, PyObject *args)
469 {
470   struct symtab *symtab = NULL;
471   ltpy_iterator_object *iter_obj = (ltpy_iterator_object *) self;
472 
473   symtab = symtab_object_to_symtab (get_symtab (iter_obj->source));
474 
475   if (symtab == NULL)
476     Py_RETURN_FALSE;
477 
478   Py_RETURN_TRUE;
479 }
480 
481 
482 
483 static PyMethodDef linetable_object_methods[] = {
484   { "line", ltpy_get_pcs_for_line, METH_VARARGS,
485     "line (lineno) -> Tuple\n\
486 Return executable locations for a given source line." },
487   { "has_line", ltpy_has_line, METH_VARARGS,
488     "has_line (lineno) -> Boolean\n\
489 Return TRUE if this line has executable information, FALSE if not." },
490   { "source_lines", ltpy_get_all_source_lines, METH_NOARGS,
491     "source_lines () -> FrozenSet\n\
492 Return a frozen set of all executable source lines." },
493   { "is_valid", ltpy_is_valid, METH_NOARGS,
494     "is_valid () -> Boolean.\n\
495 Return True if this Linetable is valid, False if not." },
496   {NULL}  /* Sentinel */
497 };
498 
499 PyTypeObject linetable_object_type = {
500   PyVarObject_HEAD_INIT (NULL, 0)
501   "gdb.LineTable",	          /*tp_name*/
502   sizeof (linetable_object),	  /*tp_basicsize*/
503   0,				  /*tp_itemsize*/
504   ltpy_dealloc,                   /*tp_dealloc*/
505   0,				  /*tp_print*/
506   0,				  /*tp_getattr*/
507   0,				  /*tp_setattr*/
508   0,				  /*tp_compare*/
509   0,				  /*tp_repr*/
510   0,				  /*tp_as_number*/
511   0,				  /*tp_as_sequence*/
512   0,				  /*tp_as_mapping*/
513   0,				  /*tp_hash */
514   0,				  /*tp_call*/
515   0,				  /*tp_str*/
516   0,				  /*tp_getattro*/
517   0,				  /*tp_setattro*/
518   0,				  /*tp_as_buffer*/
519   Py_TPFLAGS_DEFAULT,             /*tp_flags*/
520   "GDB line table object",	  /* tp_doc */
521   0,				  /* tp_traverse */
522   0,				  /* tp_clear */
523   0,				  /* tp_richcompare */
524   0,				  /* tp_weaklistoffset */
525   ltpy_iter,			  /* tp_iter */
526   0,				  /* tp_iternext */
527   linetable_object_methods,	  /* tp_methods */
528   0,				  /* tp_members */
529   0,	                          /* tp_getset */
530   0,				  /* tp_base */
531   0,				  /* tp_dict */
532   0,				  /* tp_descr_get */
533   0,				  /* tp_descr_set */
534   0,				  /* tp_dictoffset */
535   0,    			  /* tp_init */
536   0,				  /* tp_alloc */
537 };
538 
539 static PyMethodDef ltpy_iterator_methods[] = {
540   { "is_valid", ltpy_iter_is_valid, METH_NOARGS,
541     "is_valid () -> Boolean.\n\
542 Return True if this Linetable iterator is valid, False if not." },
543   {NULL}  /* Sentinel */
544 };
545 
546 PyTypeObject ltpy_iterator_object_type = {
547   PyVarObject_HEAD_INIT (NULL, 0)
548   "gdb.LineTableIterator",		  /*tp_name*/
549   sizeof (ltpy_iterator_object),  /*tp_basicsize*/
550   0,				  /*tp_itemsize*/
551   ltpy_iterator_dealloc,	  /*tp_dealloc*/
552   0,				  /*tp_print*/
553   0,				  /*tp_getattr*/
554   0,				  /*tp_setattr*/
555   0,				  /*tp_compare*/
556   0,				  /*tp_repr*/
557   0,				  /*tp_as_number*/
558   0,				  /*tp_as_sequence*/
559   0,				  /*tp_as_mapping*/
560   0,				  /*tp_hash */
561   0,				  /*tp_call*/
562   0,				  /*tp_str*/
563   0,				  /*tp_getattro*/
564   0,				  /*tp_setattro*/
565   0,				  /*tp_as_buffer*/
566   Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_ITER,  /*tp_flags*/
567   "GDB line table iterator object",	      /*tp_doc */
568   0,				  /*tp_traverse */
569   0,				  /*tp_clear */
570   0,				  /*tp_richcompare */
571   0,				  /*tp_weaklistoffset */
572   ltpy_iterator,                  /*tp_iter */
573   ltpy_iternext,	          /*tp_iternext */
574   ltpy_iterator_methods           /*tp_methods */
575 };
576 
577 
578 static PyGetSetDef linetable_entry_object_getset[] = {
579   { "line", ltpy_entry_get_line, NULL,
580     "The line number in the source file.", NULL },
581   { "pc", ltpy_entry_get_pc, NULL,
582     "The memory address for this line number.", NULL },
583   { NULL }  /* Sentinel */
584 };
585 
586 PyTypeObject linetable_entry_object_type = {
587   PyVarObject_HEAD_INIT (NULL, 0)
588   "gdb.LineTableEntry",	          /*tp_name*/
589   sizeof (linetable_entry_object), /*tp_basicsize*/
590   0,				  /*tp_itemsize*/
591   0,                              /*tp_dealloc*/
592   0,				  /*tp_print*/
593   0,				  /*tp_getattr*/
594   0,				  /*tp_setattr*/
595   0,				  /*tp_compare*/
596   0,				  /*tp_repr*/
597   0,				  /*tp_as_number*/
598   0,				  /*tp_as_sequence*/
599   0,				  /*tp_as_mapping*/
600   0,				  /*tp_hash */
601   0,				  /*tp_call*/
602   0,				  /*tp_str*/
603   0,				  /*tp_getattro*/
604   0,				  /*tp_setattro*/
605   0,				  /*tp_as_buffer*/
606   Py_TPFLAGS_DEFAULT,             /*tp_flags*/
607   "GDB line table entry object",  /* tp_doc */
608   0,				  /* tp_traverse */
609   0,				  /* tp_clear */
610   0,				  /* tp_richcompare */
611   0,				  /* tp_weaklistoffset */
612   0,			          /* tp_iter */
613   0,				  /* tp_iternext */
614   0,                              /* tp_methods */
615   0,				  /* tp_members */
616   linetable_entry_object_getset,  /* tp_getset */
617   0,				  /* tp_base */
618   0,				  /* tp_dict */
619   0,				  /* tp_descr_get */
620   0,				  /* tp_descr_set */
621   0,				  /* tp_dictoffset */
622   0,	                          /* tp_init */
623   0,				  /* tp_alloc */
624 };
625