1 /* Python interface to symbols.
3 Copyright (C) 2008-2019 Free Software Foundation, Inc.
5 This file is part of GDB.
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.
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.
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/>. */
24 #include "python-internal.h"
27 typedef struct sympy_symbol_object
{
29 /* The GDB symbol structure this object is wrapping. */
30 struct symbol
*symbol
;
31 /* A symbol object is associated with an objfile, so keep track with
32 doubly-linked list, rooted in the objfile. This lets us
33 invalidate the underlying struct symbol when the objfile is
35 struct sympy_symbol_object
*prev
;
36 struct sympy_symbol_object
*next
;
39 /* Require a valid symbol. All access to symbol_object->symbol should be
40 gated by this call. */
41 #define SYMPY_REQUIRE_VALID(symbol_obj, symbol) \
43 symbol = symbol_object_to_symbol (symbol_obj); \
46 PyErr_SetString (PyExc_RuntimeError, \
47 _("Symbol is invalid.")); \
52 static const struct objfile_data
*sympy_objfile_data_key
;
55 sympy_str (PyObject
*self
)
58 struct symbol
*symbol
= NULL
;
60 SYMPY_REQUIRE_VALID (self
, symbol
);
62 result
= PyString_FromString (SYMBOL_PRINT_NAME (symbol
));
68 sympy_get_type (PyObject
*self
, void *closure
)
70 struct symbol
*symbol
= NULL
;
72 SYMPY_REQUIRE_VALID (self
, symbol
);
74 if (SYMBOL_TYPE (symbol
) == NULL
)
80 return type_to_type_object (SYMBOL_TYPE (symbol
));
84 sympy_get_symtab (PyObject
*self
, void *closure
)
86 struct symbol
*symbol
= NULL
;
88 SYMPY_REQUIRE_VALID (self
, symbol
);
90 if (!SYMBOL_OBJFILE_OWNED (symbol
))
93 return symtab_to_symtab_object (symbol_symtab (symbol
));
97 sympy_get_name (PyObject
*self
, void *closure
)
99 struct symbol
*symbol
= NULL
;
101 SYMPY_REQUIRE_VALID (self
, symbol
);
103 return PyString_FromString (SYMBOL_NATURAL_NAME (symbol
));
107 sympy_get_linkage_name (PyObject
*self
, void *closure
)
109 struct symbol
*symbol
= NULL
;
111 SYMPY_REQUIRE_VALID (self
, symbol
);
113 return PyString_FromString (SYMBOL_LINKAGE_NAME (symbol
));
117 sympy_get_print_name (PyObject
*self
, void *closure
)
119 struct symbol
*symbol
= NULL
;
121 SYMPY_REQUIRE_VALID (self
, symbol
);
123 return sympy_str (self
);
127 sympy_get_addr_class (PyObject
*self
, void *closure
)
129 struct symbol
*symbol
= NULL
;
131 SYMPY_REQUIRE_VALID (self
, symbol
);
133 return PyInt_FromLong (SYMBOL_CLASS (symbol
));
137 sympy_is_argument (PyObject
*self
, void *closure
)
139 struct symbol
*symbol
= NULL
;
141 SYMPY_REQUIRE_VALID (self
, symbol
);
143 return PyBool_FromLong (SYMBOL_IS_ARGUMENT (symbol
));
147 sympy_is_constant (PyObject
*self
, void *closure
)
149 struct symbol
*symbol
= NULL
;
150 enum address_class theclass
;
152 SYMPY_REQUIRE_VALID (self
, symbol
);
154 theclass
= SYMBOL_CLASS (symbol
);
156 return PyBool_FromLong (theclass
== LOC_CONST
|| theclass
== LOC_CONST_BYTES
);
160 sympy_is_function (PyObject
*self
, void *closure
)
162 struct symbol
*symbol
= NULL
;
163 enum address_class theclass
;
165 SYMPY_REQUIRE_VALID (self
, symbol
);
167 theclass
= SYMBOL_CLASS (symbol
);
169 return PyBool_FromLong (theclass
== LOC_BLOCK
);
173 sympy_is_variable (PyObject
*self
, void *closure
)
175 struct symbol
*symbol
= NULL
;
176 enum address_class theclass
;
178 SYMPY_REQUIRE_VALID (self
, symbol
);
180 theclass
= SYMBOL_CLASS (symbol
);
182 return PyBool_FromLong (!SYMBOL_IS_ARGUMENT (symbol
)
183 && (theclass
== LOC_LOCAL
|| theclass
== LOC_REGISTER
184 || theclass
== LOC_STATIC
|| theclass
== LOC_COMPUTED
185 || theclass
== LOC_OPTIMIZED_OUT
));
188 /* Implementation of gdb.Symbol.needs_frame -> Boolean.
189 Returns true iff the symbol needs a frame for evaluation. */
192 sympy_needs_frame (PyObject
*self
, void *closure
)
194 struct symbol
*symbol
= NULL
;
197 SYMPY_REQUIRE_VALID (self
, symbol
);
201 result
= symbol_read_needs_frame (symbol
);
203 CATCH (except
, RETURN_MASK_ALL
)
205 GDB_PY_HANDLE_EXCEPTION (except
);
214 /* Implementation of gdb.Symbol.line -> int.
215 Returns the line number at which the symbol was defined. */
218 sympy_line (PyObject
*self
, void *closure
)
220 struct symbol
*symbol
= NULL
;
222 SYMPY_REQUIRE_VALID (self
, symbol
);
224 return PyInt_FromLong (SYMBOL_LINE (symbol
));
227 /* Implementation of gdb.Symbol.is_valid (self) -> Boolean.
228 Returns True if this Symbol still exists in GDB. */
231 sympy_is_valid (PyObject
*self
, PyObject
*args
)
233 struct symbol
*symbol
= NULL
;
235 symbol
= symbol_object_to_symbol (self
);
242 /* Implementation of gdb.Symbol.value (self[, frame]) -> gdb.Value. Returns
243 the value of the symbol, or an error in various circumstances. */
246 sympy_value (PyObject
*self
, PyObject
*args
)
248 struct symbol
*symbol
= NULL
;
249 struct frame_info
*frame_info
= NULL
;
250 PyObject
*frame_obj
= NULL
;
251 struct value
*value
= NULL
;
253 if (!PyArg_ParseTuple (args
, "|O", &frame_obj
))
256 if (frame_obj
!= NULL
&& !PyObject_TypeCheck (frame_obj
, &frame_object_type
))
258 PyErr_SetString (PyExc_TypeError
, "argument is not a frame");
262 SYMPY_REQUIRE_VALID (self
, symbol
);
263 if (SYMBOL_CLASS (symbol
) == LOC_TYPEDEF
)
265 PyErr_SetString (PyExc_TypeError
, "cannot get the value of a typedef");
271 if (frame_obj
!= NULL
)
273 frame_info
= frame_object_to_frame_info (frame_obj
);
274 if (frame_info
== NULL
)
275 error (_("invalid frame"));
278 if (symbol_read_needs_frame (symbol
) && frame_info
== NULL
)
279 error (_("symbol requires a frame to compute its value"));
281 /* TODO: currently, we have no way to recover the block in which SYMBOL
282 was found, so we have no block to pass to read_var_value. This will
283 yield an incorrect value when symbol is not local to FRAME_INFO (this
284 can happen with nested functions). */
285 value
= read_var_value (symbol
, NULL
, frame_info
);
287 CATCH (except
, RETURN_MASK_ALL
)
289 GDB_PY_HANDLE_EXCEPTION (except
);
293 return value_to_value_object (value
);
296 /* Given a symbol, and a symbol_object that has previously been
297 allocated and initialized, populate the symbol_object with the
298 struct symbol data. Also, register the symbol_object life-cycle
299 with the life-cycle of the object file associated with this
300 symbol, if needed. */
302 set_symbol (symbol_object
*obj
, struct symbol
*symbol
)
304 obj
->symbol
= symbol
;
306 if (SYMBOL_OBJFILE_OWNED (symbol
)
307 && symbol_symtab (symbol
) != NULL
)
309 struct objfile
*objfile
= symbol_objfile (symbol
);
311 obj
->next
= ((struct sympy_symbol_object
*)
312 objfile_data (objfile
, sympy_objfile_data_key
));
314 obj
->next
->prev
= obj
;
315 set_objfile_data (objfile
, sympy_objfile_data_key
, obj
);
321 /* Create a new symbol object (gdb.Symbol) that encapsulates the struct
322 symbol object from GDB. */
324 symbol_to_symbol_object (struct symbol
*sym
)
326 symbol_object
*sym_obj
;
328 sym_obj
= PyObject_New (symbol_object
, &symbol_object_type
);
330 set_symbol (sym_obj
, sym
);
332 return (PyObject
*) sym_obj
;
335 /* Return the symbol that is wrapped by this symbol object. */
337 symbol_object_to_symbol (PyObject
*obj
)
339 if (! PyObject_TypeCheck (obj
, &symbol_object_type
))
341 return ((symbol_object
*) obj
)->symbol
;
345 sympy_dealloc (PyObject
*obj
)
347 symbol_object
*sym_obj
= (symbol_object
*) obj
;
350 sym_obj
->prev
->next
= sym_obj
->next
;
351 else if (sym_obj
->symbol
!= NULL
352 && SYMBOL_OBJFILE_OWNED (sym_obj
->symbol
)
353 && symbol_symtab (sym_obj
->symbol
) != NULL
)
355 set_objfile_data (symbol_objfile (sym_obj
->symbol
),
356 sympy_objfile_data_key
, sym_obj
->next
);
359 sym_obj
->next
->prev
= sym_obj
->prev
;
360 sym_obj
->symbol
= NULL
;
364 gdb.lookup_symbol (name [, block] [, domain]) -> (symbol, is_field_of_this)
365 A tuple with 2 elements is always returned. The first is the symbol
366 object or None, the second is a boolean with the value of
367 is_a_field_of_this (see comment in lookup_symbol_in_language). */
370 gdbpy_lookup_symbol (PyObject
*self
, PyObject
*args
, PyObject
*kw
)
372 int domain
= VAR_DOMAIN
;
373 struct field_of_this_result is_a_field_of_this
;
375 static const char *keywords
[] = { "name", "block", "domain", NULL
};
376 struct symbol
*symbol
= NULL
;
377 PyObject
*block_obj
= NULL
, *sym_obj
, *bool_obj
;
378 const struct block
*block
= NULL
;
380 if (!gdb_PyArg_ParseTupleAndKeywords (args
, kw
, "s|O!i", keywords
, &name
,
381 &block_object_type
, &block_obj
,
386 block
= block_object_to_block (block_obj
);
389 struct frame_info
*selected_frame
;
393 selected_frame
= get_selected_frame (_("No frame selected."));
394 block
= get_frame_block (selected_frame
, NULL
);
396 CATCH (except
, RETURN_MASK_ALL
)
398 GDB_PY_HANDLE_EXCEPTION (except
);
405 symbol
= lookup_symbol (name
, block
, (domain_enum
) domain
,
406 &is_a_field_of_this
).symbol
;
408 CATCH (except
, RETURN_MASK_ALL
)
410 GDB_PY_HANDLE_EXCEPTION (except
);
414 gdbpy_ref
<> ret_tuple (PyTuple_New (2));
415 if (ret_tuple
== NULL
)
420 sym_obj
= symbol_to_symbol_object (symbol
);
429 PyTuple_SET_ITEM (ret_tuple
.get (), 0, sym_obj
);
431 bool_obj
= (is_a_field_of_this
.type
!= NULL
) ? Py_True
: Py_False
;
432 Py_INCREF (bool_obj
);
433 PyTuple_SET_ITEM (ret_tuple
.get (), 1, bool_obj
);
435 return ret_tuple
.release ();
439 gdb.lookup_global_symbol (name [, domain]) -> symbol or None. */
442 gdbpy_lookup_global_symbol (PyObject
*self
, PyObject
*args
, PyObject
*kw
)
444 int domain
= VAR_DOMAIN
;
446 static const char *keywords
[] = { "name", "domain", NULL
};
447 struct symbol
*symbol
= NULL
;
450 if (!gdb_PyArg_ParseTupleAndKeywords (args
, kw
, "s|i", keywords
, &name
,
456 symbol
= lookup_global_symbol (name
, NULL
, (domain_enum
) domain
).symbol
;
458 CATCH (except
, RETURN_MASK_ALL
)
460 GDB_PY_HANDLE_EXCEPTION (except
);
466 sym_obj
= symbol_to_symbol_object (symbol
);
479 /* This function is called when an objfile is about to be freed.
480 Invalidate the symbol as further actions on the symbol would result
481 in bad data. All access to obj->symbol should be gated by
482 SYMPY_REQUIRE_VALID which will raise an exception on invalid
485 del_objfile_symbols (struct objfile
*objfile
, void *datum
)
487 symbol_object
*obj
= (symbol_object
*) datum
;
490 symbol_object
*next
= obj
->next
;
501 gdbpy_initialize_symbols (void)
503 if (PyType_Ready (&symbol_object_type
) < 0)
506 /* Register an objfile "free" callback so we can properly
507 invalidate symbol when an object file that is about to be
509 sympy_objfile_data_key
510 = register_objfile_data_with_cleanup (NULL
, del_objfile_symbols
);
512 if (PyModule_AddIntConstant (gdb_module
, "SYMBOL_LOC_UNDEF", LOC_UNDEF
) < 0
513 || PyModule_AddIntConstant (gdb_module
, "SYMBOL_LOC_CONST",
515 || PyModule_AddIntConstant (gdb_module
, "SYMBOL_LOC_STATIC",
517 || PyModule_AddIntConstant (gdb_module
, "SYMBOL_LOC_REGISTER",
519 || PyModule_AddIntConstant (gdb_module
, "SYMBOL_LOC_ARG",
521 || PyModule_AddIntConstant (gdb_module
, "SYMBOL_LOC_REF_ARG",
523 || PyModule_AddIntConstant (gdb_module
, "SYMBOL_LOC_LOCAL",
525 || PyModule_AddIntConstant (gdb_module
, "SYMBOL_LOC_TYPEDEF",
527 || PyModule_AddIntConstant (gdb_module
, "SYMBOL_LOC_LABEL",
529 || PyModule_AddIntConstant (gdb_module
, "SYMBOL_LOC_BLOCK",
531 || PyModule_AddIntConstant (gdb_module
, "SYMBOL_LOC_CONST_BYTES",
533 || PyModule_AddIntConstant (gdb_module
, "SYMBOL_LOC_UNRESOLVED",
535 || PyModule_AddIntConstant (gdb_module
, "SYMBOL_LOC_OPTIMIZED_OUT",
536 LOC_OPTIMIZED_OUT
) < 0
537 || PyModule_AddIntConstant (gdb_module
, "SYMBOL_LOC_COMPUTED",
539 || PyModule_AddIntConstant (gdb_module
, "SYMBOL_LOC_COMMON_BLOCK",
540 LOC_COMMON_BLOCK
) < 0
541 || PyModule_AddIntConstant (gdb_module
, "SYMBOL_LOC_REGPARM_ADDR",
542 LOC_REGPARM_ADDR
) < 0
543 || PyModule_AddIntConstant (gdb_module
, "SYMBOL_UNDEF_DOMAIN",
545 || PyModule_AddIntConstant (gdb_module
, "SYMBOL_VAR_DOMAIN",
547 || PyModule_AddIntConstant (gdb_module
, "SYMBOL_STRUCT_DOMAIN",
549 || PyModule_AddIntConstant (gdb_module
, "SYMBOL_MODULE_DOMAIN",
551 || PyModule_AddIntConstant (gdb_module
, "SYMBOL_COMMON_BLOCK_DOMAIN",
552 COMMON_BLOCK_DOMAIN
) < 0)
555 /* These remain defined for compatibility, but as they were never
556 correct, they are no longer documented. Eventually we can remove
557 them. These exist because at one time, enum search_domain and
558 enum domain_enum_tag were combined -- but different values were
559 used differently. Here we try to give them values that will make
560 sense if they are passed to gdb.lookup_symbol. */
561 if (PyModule_AddIntConstant (gdb_module
, "SYMBOL_VARIABLES_DOMAIN",
563 || PyModule_AddIntConstant (gdb_module
, "SYMBOL_FUNCTIONS_DOMAIN",
565 || PyModule_AddIntConstant (gdb_module
, "SYMBOL_TYPES_DOMAIN",
569 return gdb_pymodule_addobject (gdb_module
, "Symbol",
570 (PyObject
*) &symbol_object_type
);
575 static gdb_PyGetSetDef symbol_object_getset
[] = {
576 { "type", sympy_get_type
, NULL
,
577 "Type of the symbol.", NULL
},
578 { "symtab", sympy_get_symtab
, NULL
,
579 "Symbol table in which the symbol appears.", NULL
},
580 { "name", sympy_get_name
, NULL
,
581 "Name of the symbol, as it appears in the source code.", NULL
},
582 { "linkage_name", sympy_get_linkage_name
, NULL
,
583 "Name of the symbol, as used by the linker (i.e., may be mangled).",
585 { "print_name", sympy_get_print_name
, NULL
,
586 "Name of the symbol in a form suitable for output.\n\
587 This is either name or linkage_name, depending on whether the user asked GDB\n\
588 to display demangled or mangled names.", NULL
},
589 { "addr_class", sympy_get_addr_class
, NULL
, "Address class of the symbol." },
590 { "is_argument", sympy_is_argument
, NULL
,
591 "True if the symbol is an argument of a function." },
592 { "is_constant", sympy_is_constant
, NULL
,
593 "True if the symbol is a constant." },
594 { "is_function", sympy_is_function
, NULL
,
595 "True if the symbol is a function or method." },
596 { "is_variable", sympy_is_variable
, NULL
,
597 "True if the symbol is a variable." },
598 { "needs_frame", sympy_needs_frame
, NULL
,
599 "True if the symbol requires a frame for evaluation." },
600 { "line", sympy_line
, NULL
,
601 "The source line number at which the symbol was defined." },
602 { NULL
} /* Sentinel */
605 static PyMethodDef symbol_object_methods
[] = {
606 { "is_valid", sympy_is_valid
, METH_NOARGS
,
607 "is_valid () -> Boolean.\n\
608 Return true if this symbol is valid, false if not." },
609 { "value", sympy_value
, METH_VARARGS
,
610 "value ([frame]) -> gdb.Value\n\
611 Return the value of the symbol." },
612 {NULL
} /* Sentinel */
615 PyTypeObject symbol_object_type
= {
616 PyVarObject_HEAD_INIT (NULL
, 0)
617 "gdb.Symbol", /*tp_name*/
618 sizeof (symbol_object
), /*tp_basicsize*/
620 sympy_dealloc
, /*tp_dealloc*/
627 0, /*tp_as_sequence*/
631 sympy_str
, /*tp_str*/
635 Py_TPFLAGS_DEFAULT
, /*tp_flags*/
636 "GDB symbol object", /*tp_doc */
639 0, /*tp_richcompare */
640 0, /*tp_weaklistoffset */
643 symbol_object_methods
, /*tp_methods */
645 symbol_object_getset
/*tp_getset */