1 /* Support for printing C values for GDB, the GNU debugger.
3 Copyright (C) 1986, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
4 1998, 1999, 2000, 2001, 2003, 2005, 2006, 2007, 2008, 2009, 2010, 2011
5 Free Software Foundation, Inc.
7 This file is part of GDB.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>. */
23 #include "gdb_string.h"
26 #include "expression.h"
35 /* Print function pointer with inferior address ADDRESS onto stdio
39 print_function_pointer_address (struct gdbarch
*gdbarch
,
41 struct ui_file
*stream
,
45 = gdbarch_convert_from_func_ptr_addr (gdbarch
, address
,
48 /* If the function pointer is represented by a description, print
49 the address of the description. */
50 if (addressprint
&& func_addr
!= address
)
52 fputs_filtered ("@", stream
);
53 fputs_filtered (paddress (gdbarch
, address
), stream
);
54 fputs_filtered (": ", stream
);
56 print_address_demangle (gdbarch
, func_addr
, stream
, demangle
);
60 /* A helper for c_textual_element_type. This checks the name of the
61 typedef. This is bogus but it isn't apparent that the compiler
62 provides us the help we may need. */
65 textual_name (const char *name
)
67 return (!strcmp (name
, "wchar_t")
68 || !strcmp (name
, "char16_t")
69 || !strcmp (name
, "char32_t"));
72 /* Apply a heuristic to decide whether an array of TYPE or a pointer
73 to TYPE should be printed as a textual string. Return non-zero if
74 it should, or zero if it should be treated as an array of integers
75 or pointer to integers. FORMAT is the current format letter, or 0
78 We guess that "char" is a character. Explicitly signed and
79 unsigned character types are also characters. Integer data from
80 vector types is not. The user can override this by using the /s
84 c_textual_element_type (struct type
*type
, char format
)
86 struct type
*true_type
, *iter_type
;
88 if (format
!= 0 && format
!= 's')
91 /* We also rely on this for its side effect of setting up all the
93 true_type
= check_typedef (type
);
95 /* TYPE_CODE_CHAR is always textual. */
96 if (TYPE_CODE (true_type
) == TYPE_CODE_CHAR
)
99 /* Any other character-like types must be integral. */
100 if (TYPE_CODE (true_type
) != TYPE_CODE_INT
)
103 /* We peel typedefs one by one, looking for a match. */
107 /* Check the name of the type. */
108 if (TYPE_NAME (iter_type
) && textual_name (TYPE_NAME (iter_type
)))
111 if (TYPE_CODE (iter_type
) != TYPE_CODE_TYPEDEF
)
114 /* Peel a single typedef. If the typedef doesn't have a target
115 type, we use check_typedef and hope the result is ok -- it
116 might be for C++, where wchar_t is a built-in type. */
117 if (TYPE_TARGET_TYPE (iter_type
))
118 iter_type
= TYPE_TARGET_TYPE (iter_type
);
120 iter_type
= check_typedef (iter_type
);
125 /* Print this as a string if we can manage it. For now, no wide
126 character support. */
127 if (TYPE_CODE (true_type
) == TYPE_CODE_INT
128 && TYPE_LENGTH (true_type
) == 1)
133 /* If a one-byte TYPE_CODE_INT is missing the not-a-character
134 flag, then we treat it as text; otherwise, we assume it's
135 being used as data. */
136 if (TYPE_CODE (true_type
) == TYPE_CODE_INT
137 && TYPE_LENGTH (true_type
) == 1
138 && !TYPE_NOTTEXT (true_type
))
145 /* See val_print for a description of the various parameters of this
146 function; they are identical. The semantics of the return value is
147 also identical to val_print. */
150 c_val_print (struct type
*type
, const gdb_byte
*valaddr
,
151 int embedded_offset
, CORE_ADDR address
,
152 struct ui_file
*stream
, int recurse
,
153 const struct value
*original_value
,
154 const struct value_print_options
*options
)
156 struct gdbarch
*gdbarch
= get_type_arch (type
);
157 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
158 unsigned int i
= 0; /* Number of characters printed. */
160 struct type
*elttype
, *unresolved_elttype
;
161 struct type
*unresolved_type
= type
;
166 CHECK_TYPEDEF (type
);
167 switch (TYPE_CODE (type
))
169 case TYPE_CODE_ARRAY
:
170 unresolved_elttype
= TYPE_TARGET_TYPE (type
);
171 elttype
= check_typedef (unresolved_elttype
);
172 if (TYPE_LENGTH (type
) > 0 && TYPE_LENGTH (unresolved_elttype
) > 0)
174 LONGEST low_bound
, high_bound
;
176 if (!get_array_bounds (type
, &low_bound
, &high_bound
))
177 error (_("Could not determine the array high bound"));
179 eltlen
= TYPE_LENGTH (elttype
);
180 len
= high_bound
- low_bound
+ 1;
181 if (options
->prettyprint_arrays
)
183 print_spaces_filtered (2 + 2 * recurse
, stream
);
186 /* Print arrays of textual chars with a string syntax, as
187 long as the entire array is valid. */
188 if (c_textual_element_type (unresolved_elttype
,
190 && value_bytes_available (original_value
, embedded_offset
,
192 && value_bits_valid (original_value
,
193 TARGET_CHAR_BIT
* embedded_offset
,
194 TARGET_CHAR_BIT
* TYPE_LENGTH (type
)))
196 /* If requested, look for the first null char and only
197 print elements up to it. */
198 if (options
->stop_print_at_null
)
200 unsigned int temp_len
;
204 && temp_len
< options
->print_max
205 && extract_unsigned_integer (valaddr
+ embedded_offset
207 eltlen
, byte_order
) != 0);
213 LA_PRINT_STRING (stream
, unresolved_elttype
,
214 valaddr
+ embedded_offset
, len
,
220 fprintf_filtered (stream
, "{");
221 /* If this is a virtual function table, print the 0th
222 entry specially, and the rest of the members
224 if (cp_is_vtbl_ptr_type (elttype
))
227 fprintf_filtered (stream
, _("%d vtable entries"),
234 val_print_array_elements (type
, valaddr
, embedded_offset
,
236 recurse
, original_value
, options
, i
);
237 fprintf_filtered (stream
, "}");
241 /* Array of unspecified length: treat like pointer to first
243 addr
= address
+ embedded_offset
;
244 goto print_unpacked_pointer
;
246 case TYPE_CODE_MEMBERPTR
:
249 val_print_scalar_formatted (type
, valaddr
, embedded_offset
,
250 original_value
, options
, 0, stream
);
253 cp_print_class_member (valaddr
+ embedded_offset
, type
, stream
, "&");
256 case TYPE_CODE_METHODPTR
:
257 cplus_print_method_ptr (valaddr
+ embedded_offset
, type
, stream
);
261 if (options
->format
&& options
->format
!= 's')
263 val_print_scalar_formatted (type
, valaddr
, embedded_offset
,
264 original_value
, options
, 0, stream
);
267 if (options
->vtblprint
&& cp_is_vtbl_ptr_type (type
))
269 /* Print the unmangled name if desired. */
270 /* Print vtable entry - we only get here if we ARE using
271 -fvtable_thunks. (Otherwise, look under
272 TYPE_CODE_STRUCT.) */
274 = extract_typed_address (valaddr
+ embedded_offset
, type
);
276 print_function_pointer_address (gdbarch
, addr
, stream
,
277 options
->addressprint
);
280 unresolved_elttype
= TYPE_TARGET_TYPE (type
);
281 elttype
= check_typedef (unresolved_elttype
);
283 addr
= unpack_pointer (type
, valaddr
+ embedded_offset
);
284 print_unpacked_pointer
:
286 if (TYPE_CODE (elttype
) == TYPE_CODE_FUNC
)
288 /* Try to print what function it points to. */
289 print_function_pointer_address (gdbarch
, addr
, stream
,
290 options
->addressprint
);
291 /* Return value is irrelevant except for string
296 if (options
->addressprint
)
297 fputs_filtered (paddress (gdbarch
, addr
), stream
);
299 /* For a pointer to a textual type, also print the string
300 pointed to, unless pointer is null. */
302 if (c_textual_element_type (unresolved_elttype
,
306 i
= val_print_string (unresolved_elttype
, NULL
,
310 else if (cp_is_vtbl_member (type
))
312 /* Print vtbl's nicely. */
313 CORE_ADDR vt_address
= unpack_pointer (type
,
317 struct minimal_symbol
*msymbol
=
318 lookup_minimal_symbol_by_pc (vt_address
);
319 if ((msymbol
!= NULL
)
320 && (vt_address
== SYMBOL_VALUE_ADDRESS (msymbol
)))
322 fputs_filtered (" <", stream
);
323 fputs_filtered (SYMBOL_PRINT_NAME (msymbol
), stream
);
324 fputs_filtered (">", stream
);
326 if (vt_address
&& options
->vtblprint
)
328 struct value
*vt_val
;
329 struct symbol
*wsym
= (struct symbol
*) NULL
;
331 struct block
*block
= (struct block
*) NULL
;
335 wsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (msymbol
),
341 wtype
= SYMBOL_TYPE (wsym
);
345 wtype
= unresolved_elttype
;
347 vt_val
= value_at (wtype
, vt_address
);
348 common_val_print (vt_val
, stream
, recurse
+ 1,
349 options
, current_language
);
352 fprintf_filtered (stream
, "\n");
353 print_spaces_filtered (2 + 2 * recurse
, stream
);
358 /* Return number of characters printed, including the
359 terminating '\0' if we reached the end. val_print_string
360 takes care including the terminating '\0' if
367 elttype
= check_typedef (TYPE_TARGET_TYPE (type
));
368 if (options
->addressprint
)
371 = extract_typed_address (valaddr
+ embedded_offset
, type
);
373 fprintf_filtered (stream
, "@");
374 fputs_filtered (paddress (gdbarch
, addr
), stream
);
375 if (options
->deref_ref
)
376 fputs_filtered (": ", stream
);
378 /* De-reference the reference. */
379 if (options
->deref_ref
)
381 if (TYPE_CODE (elttype
) != TYPE_CODE_UNDEF
)
383 struct value
*deref_val
;
385 deref_val
= coerce_ref_if_computed (original_value
);
386 if (deref_val
!= NULL
)
388 /* More complicated computed references are not supported. */
389 gdb_assert (embedded_offset
== 0);
392 deref_val
= value_at (TYPE_TARGET_TYPE (type
),
393 unpack_pointer (type
,
395 + embedded_offset
)));
397 common_val_print (deref_val
, stream
, recurse
, options
,
401 fputs_filtered ("???", stream
);
405 case TYPE_CODE_UNION
:
406 if (recurse
&& !options
->unionprint
)
408 fprintf_filtered (stream
, "{...}");
412 case TYPE_CODE_STRUCT
:
413 /*FIXME: Abstract this away. */
414 if (options
->vtblprint
&& cp_is_vtbl_ptr_type (type
))
416 /* Print the unmangled name if desired. */
417 /* Print vtable entry - we only get here if NOT using
418 -fvtable_thunks. (Otherwise, look under
420 int offset
= (embedded_offset
421 + TYPE_FIELD_BITPOS (type
,
422 VTBL_FNADDR_OFFSET
) / 8);
423 struct type
*field_type
= TYPE_FIELD_TYPE (type
,
426 = extract_typed_address (valaddr
+ offset
, field_type
);
428 print_function_pointer_address (gdbarch
, addr
, stream
,
429 options
->addressprint
);
432 cp_print_value_fields_rtti (type
, valaddr
,
433 embedded_offset
, address
,
435 original_value
, options
,
442 val_print_scalar_formatted (type
, valaddr
, embedded_offset
,
443 original_value
, options
, 0, stream
);
446 len
= TYPE_NFIELDS (type
);
447 val
= unpack_long (type
, valaddr
+ embedded_offset
);
448 for (i
= 0; i
< len
; i
++)
451 if (val
== TYPE_FIELD_BITPOS (type
, i
))
458 fputs_filtered (TYPE_FIELD_NAME (type
, i
), stream
);
462 print_longest (stream
, 'd', 0, val
);
466 case TYPE_CODE_FLAGS
:
468 val_print_scalar_formatted (type
, valaddr
, embedded_offset
,
469 original_value
, options
, 0, stream
);
471 val_print_type_code_flags (type
, valaddr
+ embedded_offset
,
476 case TYPE_CODE_METHOD
:
479 val_print_scalar_formatted (type
, valaddr
, embedded_offset
,
480 original_value
, options
, 0, stream
);
483 /* FIXME, we should consider, at least for ANSI C language,
484 eliminating the distinction made between FUNCs and POINTERs
486 fprintf_filtered (stream
, "{");
487 type_print (type
, "", stream
, -1);
488 fprintf_filtered (stream
, "} ");
489 /* Try to print what function it points to, and its address. */
490 print_address_demangle (gdbarch
, address
, stream
, demangle
);
494 if (options
->format
|| options
->output_format
)
496 struct value_print_options opts
= *options
;
497 opts
.format
= (options
->format
? options
->format
498 : options
->output_format
);
499 val_print_scalar_formatted (type
, valaddr
, embedded_offset
,
500 original_value
, &opts
, 0, stream
);
504 val
= unpack_long (type
, valaddr
+ embedded_offset
);
506 fputs_filtered ("false", stream
);
508 fputs_filtered ("true", stream
);
510 print_longest (stream
, 'd', 0, val
);
514 case TYPE_CODE_RANGE
:
515 /* FIXME: create_range_type does not set the unsigned bit in a
516 range type (I think it probably should copy it from the
517 target type), so we won't print values which are too large to
518 fit in a signed integer correctly. */
519 /* FIXME: Doesn't handle ranges of enums correctly. (Can't just
520 print with the target type, though, because the size of our
521 type and the target type might differ). */
525 if (options
->format
|| options
->output_format
)
527 struct value_print_options opts
= *options
;
529 opts
.format
= (options
->format
? options
->format
530 : options
->output_format
);
531 val_print_scalar_formatted (type
, valaddr
, embedded_offset
,
532 original_value
, &opts
, 0, stream
);
536 val_print_type_code_int (type
, valaddr
+ embedded_offset
,
538 /* C and C++ has no single byte int type, char is used
539 instead. Since we don't know whether the value is really
540 intended to be used as an integer or a character, print
541 the character equivalent as well. */
542 if (c_textual_element_type (unresolved_type
, options
->format
))
544 fputs_filtered (" ", stream
);
545 LA_PRINT_CHAR (unpack_long (type
, valaddr
+ embedded_offset
),
546 unresolved_type
, stream
);
552 if (options
->format
|| options
->output_format
)
554 struct value_print_options opts
= *options
;
555 opts
.format
= (options
->format
? options
->format
556 : options
->output_format
);
557 val_print_scalar_formatted (type
, valaddr
, embedded_offset
,
558 original_value
, &opts
, 0, stream
);
562 val
= unpack_long (type
, valaddr
+ embedded_offset
);
563 if (TYPE_UNSIGNED (type
))
564 fprintf_filtered (stream
, "%u", (unsigned int) val
);
566 fprintf_filtered (stream
, "%d", (int) val
);
567 fputs_filtered (" ", stream
);
568 LA_PRINT_CHAR (val
, unresolved_type
, stream
);
575 val_print_scalar_formatted (type
, valaddr
, embedded_offset
,
576 original_value
, options
, 0, stream
);
580 print_floating (valaddr
+ embedded_offset
, type
, stream
);
584 case TYPE_CODE_DECFLOAT
:
586 val_print_scalar_formatted (type
, valaddr
, embedded_offset
,
587 original_value
, options
, 0, stream
);
589 print_decimal_floating (valaddr
+ embedded_offset
,
594 fprintf_filtered (stream
, "void");
597 case TYPE_CODE_ERROR
:
598 fprintf_filtered (stream
, "%s", TYPE_ERROR_NAME (type
));
601 case TYPE_CODE_UNDEF
:
602 /* This happens (without TYPE_FLAG_STUB set) on systems which
603 don't use dbx xrefs (NO_DBX_XREFS in gcc) if a file has a
604 "struct foo *bar" and no complete type for struct foo in that
606 fprintf_filtered (stream
, _("<incomplete type>"));
609 case TYPE_CODE_COMPLEX
:
611 val_print_scalar_formatted (TYPE_TARGET_TYPE (type
),
612 valaddr
, embedded_offset
,
613 original_value
, options
, 0, stream
);
615 print_floating (valaddr
+ embedded_offset
,
616 TYPE_TARGET_TYPE (type
),
618 fprintf_filtered (stream
, " + ");
620 val_print_scalar_formatted (TYPE_TARGET_TYPE (type
),
623 + TYPE_LENGTH (TYPE_TARGET_TYPE (type
)),
627 print_floating (valaddr
+ embedded_offset
628 + TYPE_LENGTH (TYPE_TARGET_TYPE (type
)),
629 TYPE_TARGET_TYPE (type
),
631 fprintf_filtered (stream
, " * I");
635 error (_("Invalid C/C++ type code %d in symbol table."),
643 c_value_print (struct value
*val
, struct ui_file
*stream
,
644 const struct value_print_options
*options
)
646 struct type
*type
, *real_type
, *val_type
;
647 int full
, top
, using_enc
;
648 struct value_print_options opts
= *options
;
652 /* If it is a pointer, indicate what it points to.
654 Print type also if it is a reference.
656 C++: if it is a member pointer, we will take care
657 of that when we print it. */
659 /* Preserve the original type before stripping typedefs. We prefer
660 to pass down the original type when possible, but for local
661 checks it is better to look past the typedefs. */
662 val_type
= value_type (val
);
663 type
= check_typedef (val_type
);
665 if (TYPE_CODE (type
) == TYPE_CODE_PTR
666 || TYPE_CODE (type
) == TYPE_CODE_REF
)
668 /* Hack: remove (char *) for char strings. Their
669 type is indicated by the quoted string anyway.
670 (Don't use c_textual_element_type here; quoted strings
671 are always exactly (char *), (wchar_t *), or the like. */
672 if (TYPE_CODE (val_type
) == TYPE_CODE_PTR
673 && TYPE_NAME (val_type
) == NULL
674 && TYPE_NAME (TYPE_TARGET_TYPE (val_type
)) != NULL
675 && (strcmp (TYPE_NAME (TYPE_TARGET_TYPE (val_type
)),
677 || textual_name (TYPE_NAME (TYPE_TARGET_TYPE (val_type
)))))
681 else if (options
->objectprint
682 && (TYPE_CODE (TYPE_TARGET_TYPE (type
)) == TYPE_CODE_CLASS
))
685 if (TYPE_CODE(type
) == TYPE_CODE_REF
)
687 /* Copy value, change to pointer, so we don't get an
688 error about a non-pointer type in
689 value_rtti_target_type. */
690 struct value
*temparg
;
691 temparg
=value_copy(val
);
692 deprecated_set_value_type
693 (temparg
, lookup_pointer_type (TYPE_TARGET_TYPE (type
)));
696 /* Pointer to class, check real type of object. */
697 fprintf_filtered (stream
, "(");
699 if (value_entirely_available (val
))
701 real_type
= value_rtti_target_type (val
, &full
, &top
, &using_enc
);
704 /* RTTI entry found. */
705 if (TYPE_CODE (type
) == TYPE_CODE_PTR
)
707 /* Create a pointer type pointing to the real
709 type
= lookup_pointer_type (real_type
);
713 /* Create a reference type referencing the real
715 type
= lookup_reference_type (real_type
);
717 /* Need to adjust pointer value. */
718 val
= value_from_pointer (type
, value_as_address (val
) - top
);
720 /* Note: When we look up RTTI entries, we don't get
721 any information on const or volatile
725 type_print (type
, "", stream
, -1);
726 fprintf_filtered (stream
, ") ");
732 fprintf_filtered (stream
, "(");
733 type_print (value_type (val
), "", stream
, -1);
734 fprintf_filtered (stream
, ") ");
738 if (!value_initialized (val
))
739 fprintf_filtered (stream
, " [uninitialized] ");
741 if (options
->objectprint
&& (TYPE_CODE (type
) == TYPE_CODE_CLASS
))
743 /* Attempt to determine real type of object. */
744 real_type
= value_rtti_type (val
, &full
, &top
, &using_enc
);
747 /* We have RTTI information, so use it. */
748 val
= value_full_object (val
, real_type
,
749 full
, top
, using_enc
);
750 fprintf_filtered (stream
, "(%s%s) ",
751 TYPE_NAME (real_type
),
752 full
? "" : _(" [incomplete object]"));
753 /* Print out object: enclosing type is same as real_type if
755 return val_print (value_enclosing_type (val
),
756 value_contents_for_printing (val
), 0,
757 value_address (val
), stream
, 0,
758 val
, &opts
, current_language
);
759 /* Note: When we look up RTTI entries, we don't get any
760 information on const or volatile attributes. */
762 else if (type
!= check_typedef (value_enclosing_type (val
)))
764 /* No RTTI information, so let's do our best. */
765 fprintf_filtered (stream
, "(%s ?) ",
766 TYPE_NAME (value_enclosing_type (val
)));
767 return val_print (value_enclosing_type (val
),
768 value_contents_for_printing (val
), 0,
769 value_address (val
), stream
, 0,
770 val
, &opts
, current_language
);
772 /* Otherwise, we end up at the return outside this "if". */
775 return val_print (val_type
, value_contents_for_printing (val
),
776 value_embedded_offset (val
),
779 val
, &opts
, current_language
);