1 /* Support for printing C values for GDB, the GNU debugger.
3 Copyright (C) 1986, 1988-1989, 1991-2001, 2003, 2005-2012 Free
4 Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
22 #include "gdb_string.h"
25 #include "expression.h"
34 /* A helper for c_textual_element_type. This checks the name of the
35 typedef. This is bogus but it isn't apparent that the compiler
36 provides us the help we may need. */
39 textual_name (const char *name
)
41 return (!strcmp (name
, "wchar_t")
42 || !strcmp (name
, "char16_t")
43 || !strcmp (name
, "char32_t"));
46 /* Apply a heuristic to decide whether an array of TYPE or a pointer
47 to TYPE should be printed as a textual string. Return non-zero if
48 it should, or zero if it should be treated as an array of integers
49 or pointer to integers. FORMAT is the current format letter, or 0
52 We guess that "char" is a character. Explicitly signed and
53 unsigned character types are also characters. Integer data from
54 vector types is not. The user can override this by using the /s
58 c_textual_element_type (struct type
*type
, char format
)
60 struct type
*true_type
, *iter_type
;
62 if (format
!= 0 && format
!= 's')
65 /* We also rely on this for its side effect of setting up all the
67 true_type
= check_typedef (type
);
69 /* TYPE_CODE_CHAR is always textual. */
70 if (TYPE_CODE (true_type
) == TYPE_CODE_CHAR
)
73 /* Any other character-like types must be integral. */
74 if (TYPE_CODE (true_type
) != TYPE_CODE_INT
)
77 /* We peel typedefs one by one, looking for a match. */
81 /* Check the name of the type. */
82 if (TYPE_NAME (iter_type
) && textual_name (TYPE_NAME (iter_type
)))
85 if (TYPE_CODE (iter_type
) != TYPE_CODE_TYPEDEF
)
88 /* Peel a single typedef. If the typedef doesn't have a target
89 type, we use check_typedef and hope the result is ok -- it
90 might be for C++, where wchar_t is a built-in type. */
91 if (TYPE_TARGET_TYPE (iter_type
))
92 iter_type
= TYPE_TARGET_TYPE (iter_type
);
94 iter_type
= check_typedef (iter_type
);
99 /* Print this as a string if we can manage it. For now, no wide
100 character support. */
101 if (TYPE_CODE (true_type
) == TYPE_CODE_INT
102 && TYPE_LENGTH (true_type
) == 1)
107 /* If a one-byte TYPE_CODE_INT is missing the not-a-character
108 flag, then we treat it as text; otherwise, we assume it's
109 being used as data. */
110 if (TYPE_CODE (true_type
) == TYPE_CODE_INT
111 && TYPE_LENGTH (true_type
) == 1
112 && !TYPE_NOTTEXT (true_type
))
119 /* Decorations for C. */
121 static const struct generic_val_print_decorations c_decorations
=
131 /* See val_print for a description of the various parameters of this
132 function; they are identical. */
135 c_val_print (struct type
*type
, const gdb_byte
*valaddr
,
136 int embedded_offset
, CORE_ADDR address
,
137 struct ui_file
*stream
, int recurse
,
138 const struct value
*original_value
,
139 const struct value_print_options
*options
)
141 struct gdbarch
*gdbarch
= get_type_arch (type
);
142 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
143 unsigned int i
= 0; /* Number of characters printed. */
145 struct type
*elttype
, *unresolved_elttype
;
146 struct type
*unresolved_type
= type
;
150 CHECK_TYPEDEF (type
);
151 switch (TYPE_CODE (type
))
153 case TYPE_CODE_ARRAY
:
154 unresolved_elttype
= TYPE_TARGET_TYPE (type
);
155 elttype
= check_typedef (unresolved_elttype
);
156 if (TYPE_LENGTH (type
) > 0 && TYPE_LENGTH (unresolved_elttype
) > 0)
158 LONGEST low_bound
, high_bound
;
160 if (!get_array_bounds (type
, &low_bound
, &high_bound
))
161 error (_("Could not determine the array high bound"));
163 eltlen
= TYPE_LENGTH (elttype
);
164 len
= high_bound
- low_bound
+ 1;
165 if (options
->prettyprint_arrays
)
167 print_spaces_filtered (2 + 2 * recurse
, stream
);
170 /* Print arrays of textual chars with a string syntax, as
171 long as the entire array is valid. */
172 if (c_textual_element_type (unresolved_elttype
,
174 && value_bytes_available (original_value
, embedded_offset
,
176 && value_bits_valid (original_value
,
177 TARGET_CHAR_BIT
* embedded_offset
,
178 TARGET_CHAR_BIT
* TYPE_LENGTH (type
)))
180 /* If requested, look for the first null char and only
181 print elements up to it. */
182 if (options
->stop_print_at_null
)
184 unsigned int temp_len
;
188 && temp_len
< options
->print_max
189 && extract_unsigned_integer (valaddr
+ embedded_offset
191 eltlen
, byte_order
) != 0);
197 LA_PRINT_STRING (stream
, unresolved_elttype
,
198 valaddr
+ embedded_offset
, len
,
204 fprintf_filtered (stream
, "{");
205 /* If this is a virtual function table, print the 0th
206 entry specially, and the rest of the members
208 if (cp_is_vtbl_ptr_type (elttype
))
211 fprintf_filtered (stream
, _("%d vtable entries"),
218 val_print_array_elements (type
, valaddr
, embedded_offset
,
220 recurse
, original_value
, options
, i
);
221 fprintf_filtered (stream
, "}");
225 /* Array of unspecified length: treat like pointer to first
227 addr
= address
+ embedded_offset
;
228 goto print_unpacked_pointer
;
230 case TYPE_CODE_METHODPTR
:
231 cplus_print_method_ptr (valaddr
+ embedded_offset
, type
, stream
);
235 if (options
->format
&& options
->format
!= 's')
237 val_print_scalar_formatted (type
, valaddr
, embedded_offset
,
238 original_value
, options
, 0, stream
);
241 if (options
->vtblprint
&& cp_is_vtbl_ptr_type (type
))
243 /* Print the unmangled name if desired. */
244 /* Print vtable entry - we only get here if we ARE using
245 -fvtable_thunks. (Otherwise, look under
246 TYPE_CODE_STRUCT.) */
248 = extract_typed_address (valaddr
+ embedded_offset
, type
);
250 print_function_pointer_address (options
, gdbarch
, addr
, stream
);
253 unresolved_elttype
= TYPE_TARGET_TYPE (type
);
254 elttype
= check_typedef (unresolved_elttype
);
258 addr
= unpack_pointer (type
, valaddr
+ embedded_offset
);
259 print_unpacked_pointer
:
263 if (TYPE_CODE (elttype
) == TYPE_CODE_FUNC
)
265 /* Try to print what function it points to. */
266 print_function_pointer_address (options
, gdbarch
, addr
, stream
);
270 if (options
->symbol_print
)
271 want_space
= print_address_demangle (options
, gdbarch
, addr
,
273 else if (options
->addressprint
)
275 fputs_filtered (paddress (gdbarch
, addr
), stream
);
279 /* For a pointer to a textual type, also print the string
280 pointed to, unless pointer is null. */
282 if (c_textual_element_type (unresolved_elttype
,
287 fputs_filtered (" ", stream
);
288 i
= val_print_string (unresolved_elttype
, NULL
,
292 else if (cp_is_vtbl_member (type
))
294 /* Print vtbl's nicely. */
295 CORE_ADDR vt_address
= unpack_pointer (type
,
298 struct minimal_symbol
*msymbol
=
299 lookup_minimal_symbol_by_pc (vt_address
);
301 /* If 'symbol_print' is set, we did the work above. */
302 if (!options
->symbol_print
304 && (vt_address
== SYMBOL_VALUE_ADDRESS (msymbol
)))
307 fputs_filtered (" ", stream
);
308 fputs_filtered (" <", stream
);
309 fputs_filtered (SYMBOL_PRINT_NAME (msymbol
), stream
);
310 fputs_filtered (">", stream
);
314 if (vt_address
&& options
->vtblprint
)
316 struct value
*vt_val
;
317 struct symbol
*wsym
= (struct symbol
*) NULL
;
319 struct block
*block
= (struct block
*) NULL
;
323 fputs_filtered (" ", stream
);
326 wsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (msymbol
),
332 wtype
= SYMBOL_TYPE (wsym
);
336 wtype
= unresolved_elttype
;
338 vt_val
= value_at (wtype
, vt_address
);
339 common_val_print (vt_val
, stream
, recurse
+ 1,
340 options
, current_language
);
343 fprintf_filtered (stream
, "\n");
344 print_spaces_filtered (2 + 2 * recurse
, stream
);
352 case TYPE_CODE_UNION
:
353 if (recurse
&& !options
->unionprint
)
355 fprintf_filtered (stream
, "{...}");
359 case TYPE_CODE_STRUCT
:
360 /*FIXME: Abstract this away. */
361 if (options
->vtblprint
&& cp_is_vtbl_ptr_type (type
))
363 /* Print the unmangled name if desired. */
364 /* Print vtable entry - we only get here if NOT using
365 -fvtable_thunks. (Otherwise, look under
367 int offset
= (embedded_offset
368 + TYPE_FIELD_BITPOS (type
,
369 VTBL_FNADDR_OFFSET
) / 8);
370 struct type
*field_type
= TYPE_FIELD_TYPE (type
,
373 = extract_typed_address (valaddr
+ offset
, field_type
);
375 print_function_pointer_address (options
, gdbarch
, addr
, stream
);
378 cp_print_value_fields_rtti (type
, valaddr
,
379 embedded_offset
, address
,
381 original_value
, options
,
386 if (options
->format
|| options
->output_format
)
388 struct value_print_options opts
= *options
;
390 opts
.format
= (options
->format
? options
->format
391 : options
->output_format
);
392 val_print_scalar_formatted (type
, valaddr
, embedded_offset
,
393 original_value
, &opts
, 0, stream
);
397 val_print_type_code_int (type
, valaddr
+ embedded_offset
,
399 /* C and C++ has no single byte int type, char is used
400 instead. Since we don't know whether the value is really
401 intended to be used as an integer or a character, print
402 the character equivalent as well. */
403 if (c_textual_element_type (unresolved_type
, options
->format
))
405 fputs_filtered (" ", stream
);
406 LA_PRINT_CHAR (unpack_long (type
, valaddr
+ embedded_offset
),
407 unresolved_type
, stream
);
412 case TYPE_CODE_MEMBERPTR
:
413 if (!options
->format
)
415 cp_print_class_member (valaddr
+ embedded_offset
, type
, stream
, "&");
422 case TYPE_CODE_FLAGS
:
424 case TYPE_CODE_METHOD
:
426 case TYPE_CODE_RANGE
:
428 case TYPE_CODE_DECFLOAT
:
430 case TYPE_CODE_ERROR
:
431 case TYPE_CODE_UNDEF
:
432 case TYPE_CODE_COMPLEX
:
435 generic_val_print (type
, valaddr
, embedded_offset
, address
,
436 stream
, recurse
, original_value
, options
,
444 c_value_print (struct value
*val
, struct ui_file
*stream
,
445 const struct value_print_options
*options
)
447 struct type
*type
, *real_type
, *val_type
;
448 int full
, top
, using_enc
;
449 struct value_print_options opts
= *options
;
453 /* If it is a pointer, indicate what it points to.
455 Print type also if it is a reference.
457 C++: if it is a member pointer, we will take care
458 of that when we print it. */
460 /* Preserve the original type before stripping typedefs. We prefer
461 to pass down the original type when possible, but for local
462 checks it is better to look past the typedefs. */
463 val_type
= value_type (val
);
464 type
= check_typedef (val_type
);
466 if (TYPE_CODE (type
) == TYPE_CODE_PTR
467 || TYPE_CODE (type
) == TYPE_CODE_REF
)
469 /* Hack: remove (char *) for char strings. Their
470 type is indicated by the quoted string anyway.
471 (Don't use c_textual_element_type here; quoted strings
472 are always exactly (char *), (wchar_t *), or the like. */
473 if (TYPE_CODE (val_type
) == TYPE_CODE_PTR
474 && TYPE_NAME (val_type
) == NULL
475 && TYPE_NAME (TYPE_TARGET_TYPE (val_type
)) != NULL
476 && (strcmp (TYPE_NAME (TYPE_TARGET_TYPE (val_type
)),
478 || textual_name (TYPE_NAME (TYPE_TARGET_TYPE (val_type
)))))
482 else if (options
->objectprint
483 && (TYPE_CODE (TYPE_TARGET_TYPE (type
)) == TYPE_CODE_CLASS
))
486 if (TYPE_CODE(type
) == TYPE_CODE_REF
)
488 /* Copy value, change to pointer, so we don't get an
489 error about a non-pointer type in
490 value_rtti_target_type. */
491 struct value
*temparg
;
492 temparg
=value_copy(val
);
493 deprecated_set_value_type
494 (temparg
, lookup_pointer_type (TYPE_TARGET_TYPE (type
)));
497 /* Pointer to class, check real type of object. */
498 fprintf_filtered (stream
, "(");
500 if (value_entirely_available (val
))
502 real_type
= value_rtti_indirect_type (val
, &full
, &top
,
506 /* RTTI entry found. */
509 /* Need to adjust pointer value. */
510 val
= value_from_pointer (type
, value_as_address (val
) - top
);
512 /* Note: When we look up RTTI entries, we don't get
513 any information on const or volatile
517 type_print (type
, "", stream
, -1);
518 fprintf_filtered (stream
, ") ");
524 fprintf_filtered (stream
, "(");
525 type_print (value_type (val
), "", stream
, -1);
526 fprintf_filtered (stream
, ") ");
530 if (!value_initialized (val
))
531 fprintf_filtered (stream
, " [uninitialized] ");
533 if (options
->objectprint
&& (TYPE_CODE (type
) == TYPE_CODE_CLASS
))
535 /* Attempt to determine real type of object. */
536 real_type
= value_rtti_type (val
, &full
, &top
, &using_enc
);
539 /* We have RTTI information, so use it. */
540 val
= value_full_object (val
, real_type
,
541 full
, top
, using_enc
);
542 fprintf_filtered (stream
, "(%s%s) ",
543 TYPE_NAME (real_type
),
544 full
? "" : _(" [incomplete object]"));
545 /* Print out object: enclosing type is same as real_type if
547 val_print (value_enclosing_type (val
),
548 value_contents_for_printing (val
), 0,
549 value_address (val
), stream
, 0,
550 val
, &opts
, current_language
);
552 /* Note: When we look up RTTI entries, we don't get any
553 information on const or volatile attributes. */
555 else if (type
!= check_typedef (value_enclosing_type (val
)))
557 /* No RTTI information, so let's do our best. */
558 fprintf_filtered (stream
, "(%s ?) ",
559 TYPE_NAME (value_enclosing_type (val
)));
560 val_print (value_enclosing_type (val
),
561 value_contents_for_printing (val
), 0,
562 value_address (val
), stream
, 0,
563 val
, &opts
, current_language
);
566 /* Otherwise, we end up at the return outside this "if". */
569 val_print (val_type
, value_contents_for_printing (val
),
570 value_embedded_offset (val
),
573 val
, &opts
, current_language
);