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
;
151 CHECK_TYPEDEF (type
);
152 switch (TYPE_CODE (type
))
154 case TYPE_CODE_ARRAY
:
155 unresolved_elttype
= TYPE_TARGET_TYPE (type
);
156 elttype
= check_typedef (unresolved_elttype
);
157 if (TYPE_LENGTH (type
) > 0 && TYPE_LENGTH (unresolved_elttype
) > 0)
159 LONGEST low_bound
, high_bound
;
161 if (!get_array_bounds (type
, &low_bound
, &high_bound
))
162 error (_("Could not determine the array high bound"));
164 eltlen
= TYPE_LENGTH (elttype
);
165 len
= high_bound
- low_bound
+ 1;
166 if (options
->prettyprint_arrays
)
168 print_spaces_filtered (2 + 2 * recurse
, stream
);
171 /* Print arrays of textual chars with a string syntax, as
172 long as the entire array is valid. */
173 if (c_textual_element_type (unresolved_elttype
,
175 && value_bytes_available (original_value
, embedded_offset
,
177 && value_bits_valid (original_value
,
178 TARGET_CHAR_BIT
* embedded_offset
,
179 TARGET_CHAR_BIT
* TYPE_LENGTH (type
)))
181 /* If requested, look for the first null char and only
182 print elements up to it. */
183 if (options
->stop_print_at_null
)
185 unsigned int temp_len
;
189 && temp_len
< options
->print_max
190 && extract_unsigned_integer (valaddr
+ embedded_offset
192 eltlen
, byte_order
) != 0);
198 LA_PRINT_STRING (stream
, unresolved_elttype
,
199 valaddr
+ embedded_offset
, len
,
205 fprintf_filtered (stream
, "{");
206 /* If this is a virtual function table, print the 0th
207 entry specially, and the rest of the members
209 if (cp_is_vtbl_ptr_type (elttype
))
212 fprintf_filtered (stream
, _("%d vtable entries"),
219 val_print_array_elements (type
, valaddr
, embedded_offset
,
221 recurse
, original_value
, options
, i
);
222 fprintf_filtered (stream
, "}");
226 /* Array of unspecified length: treat like pointer to first
228 addr
= address
+ embedded_offset
;
229 goto print_unpacked_pointer
;
231 case TYPE_CODE_METHODPTR
:
232 cplus_print_method_ptr (valaddr
+ embedded_offset
, type
, stream
);
236 if (options
->format
&& options
->format
!= 's')
238 val_print_scalar_formatted (type
, valaddr
, embedded_offset
,
239 original_value
, options
, 0, stream
);
242 if (options
->vtblprint
&& cp_is_vtbl_ptr_type (type
))
244 /* Print the unmangled name if desired. */
245 /* Print vtable entry - we only get here if we ARE using
246 -fvtable_thunks. (Otherwise, look under
247 TYPE_CODE_STRUCT.) */
249 = extract_typed_address (valaddr
+ embedded_offset
, type
);
251 print_function_pointer_address (gdbarch
, addr
, stream
,
252 options
->addressprint
);
255 unresolved_elttype
= TYPE_TARGET_TYPE (type
);
256 elttype
= check_typedef (unresolved_elttype
);
258 addr
= unpack_pointer (type
, valaddr
+ embedded_offset
);
259 print_unpacked_pointer
:
261 if (TYPE_CODE (elttype
) == TYPE_CODE_FUNC
)
263 /* Try to print what function it points to. */
264 print_function_pointer_address (gdbarch
, addr
, stream
,
265 options
->addressprint
);
269 if (options
->addressprint
)
270 fputs_filtered (paddress (gdbarch
, addr
), stream
);
272 /* For a pointer to a textual type, also print the string
273 pointed to, unless pointer is null. */
275 if (c_textual_element_type (unresolved_elttype
,
279 i
= val_print_string (unresolved_elttype
, NULL
,
283 else if (cp_is_vtbl_member (type
))
285 /* Print vtbl's nicely. */
286 CORE_ADDR vt_address
= unpack_pointer (type
,
290 struct minimal_symbol
*msymbol
=
291 lookup_minimal_symbol_by_pc (vt_address
);
292 if ((msymbol
!= NULL
)
293 && (vt_address
== SYMBOL_VALUE_ADDRESS (msymbol
)))
295 fputs_filtered (" <", stream
);
296 fputs_filtered (SYMBOL_PRINT_NAME (msymbol
), stream
);
297 fputs_filtered (">", stream
);
299 if (vt_address
&& options
->vtblprint
)
301 struct value
*vt_val
;
302 struct symbol
*wsym
= (struct symbol
*) NULL
;
304 struct block
*block
= (struct block
*) NULL
;
308 wsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (msymbol
),
314 wtype
= SYMBOL_TYPE (wsym
);
318 wtype
= unresolved_elttype
;
320 vt_val
= value_at (wtype
, vt_address
);
321 common_val_print (vt_val
, stream
, recurse
+ 1,
322 options
, current_language
);
325 fprintf_filtered (stream
, "\n");
326 print_spaces_filtered (2 + 2 * recurse
, stream
);
334 case TYPE_CODE_UNION
:
335 if (recurse
&& !options
->unionprint
)
337 fprintf_filtered (stream
, "{...}");
341 case TYPE_CODE_STRUCT
:
342 /*FIXME: Abstract this away. */
343 if (options
->vtblprint
&& cp_is_vtbl_ptr_type (type
))
345 /* Print the unmangled name if desired. */
346 /* Print vtable entry - we only get here if NOT using
347 -fvtable_thunks. (Otherwise, look under
349 int offset
= (embedded_offset
350 + TYPE_FIELD_BITPOS (type
,
351 VTBL_FNADDR_OFFSET
) / 8);
352 struct type
*field_type
= TYPE_FIELD_TYPE (type
,
355 = extract_typed_address (valaddr
+ offset
, field_type
);
357 print_function_pointer_address (gdbarch
, addr
, stream
,
358 options
->addressprint
);
361 cp_print_value_fields_rtti (type
, valaddr
,
362 embedded_offset
, address
,
364 original_value
, options
,
369 if (options
->format
|| options
->output_format
)
371 struct value_print_options opts
= *options
;
373 opts
.format
= (options
->format
? options
->format
374 : options
->output_format
);
375 val_print_scalar_formatted (type
, valaddr
, embedded_offset
,
376 original_value
, &opts
, 0, stream
);
380 val_print_type_code_int (type
, valaddr
+ embedded_offset
,
382 /* C and C++ has no single byte int type, char is used
383 instead. Since we don't know whether the value is really
384 intended to be used as an integer or a character, print
385 the character equivalent as well. */
386 if (c_textual_element_type (unresolved_type
, options
->format
))
388 fputs_filtered (" ", stream
);
389 LA_PRINT_CHAR (unpack_long (type
, valaddr
+ embedded_offset
),
390 unresolved_type
, stream
);
395 case TYPE_CODE_MEMBERPTR
:
396 if (!options
->format
)
398 cp_print_class_member (valaddr
+ embedded_offset
, type
, stream
, "&");
405 case TYPE_CODE_FLAGS
:
407 case TYPE_CODE_METHOD
:
409 case TYPE_CODE_RANGE
:
411 case TYPE_CODE_DECFLOAT
:
413 case TYPE_CODE_ERROR
:
414 case TYPE_CODE_UNDEF
:
415 case TYPE_CODE_COMPLEX
:
418 generic_val_print (type
, valaddr
, embedded_offset
, address
,
419 stream
, recurse
, original_value
, options
,
427 c_value_print (struct value
*val
, struct ui_file
*stream
,
428 const struct value_print_options
*options
)
430 struct type
*type
, *real_type
, *val_type
;
431 int full
, top
, using_enc
;
432 struct value_print_options opts
= *options
;
436 /* If it is a pointer, indicate what it points to.
438 Print type also if it is a reference.
440 C++: if it is a member pointer, we will take care
441 of that when we print it. */
443 /* Preserve the original type before stripping typedefs. We prefer
444 to pass down the original type when possible, but for local
445 checks it is better to look past the typedefs. */
446 val_type
= value_type (val
);
447 type
= check_typedef (val_type
);
449 if (TYPE_CODE (type
) == TYPE_CODE_PTR
450 || TYPE_CODE (type
) == TYPE_CODE_REF
)
452 /* Hack: remove (char *) for char strings. Their
453 type is indicated by the quoted string anyway.
454 (Don't use c_textual_element_type here; quoted strings
455 are always exactly (char *), (wchar_t *), or the like. */
456 if (TYPE_CODE (val_type
) == TYPE_CODE_PTR
457 && TYPE_NAME (val_type
) == NULL
458 && TYPE_NAME (TYPE_TARGET_TYPE (val_type
)) != NULL
459 && (strcmp (TYPE_NAME (TYPE_TARGET_TYPE (val_type
)),
461 || textual_name (TYPE_NAME (TYPE_TARGET_TYPE (val_type
)))))
465 else if (options
->objectprint
466 && (TYPE_CODE (TYPE_TARGET_TYPE (type
)) == TYPE_CODE_CLASS
))
469 if (TYPE_CODE(type
) == TYPE_CODE_REF
)
471 /* Copy value, change to pointer, so we don't get an
472 error about a non-pointer type in
473 value_rtti_target_type. */
474 struct value
*temparg
;
475 temparg
=value_copy(val
);
476 deprecated_set_value_type
477 (temparg
, lookup_pointer_type (TYPE_TARGET_TYPE (type
)));
480 /* Pointer to class, check real type of object. */
481 fprintf_filtered (stream
, "(");
483 if (value_entirely_available (val
))
485 real_type
= value_rtti_indirect_type (val
, &full
, &top
,
489 /* RTTI entry found. */
492 /* Need to adjust pointer value. */
493 val
= value_from_pointer (type
, value_as_address (val
) - top
);
495 /* Note: When we look up RTTI entries, we don't get
496 any information on const or volatile
500 type_print (type
, "", stream
, -1);
501 fprintf_filtered (stream
, ") ");
507 fprintf_filtered (stream
, "(");
508 type_print (value_type (val
), "", stream
, -1);
509 fprintf_filtered (stream
, ") ");
513 if (!value_initialized (val
))
514 fprintf_filtered (stream
, " [uninitialized] ");
516 if (options
->objectprint
&& (TYPE_CODE (type
) == TYPE_CODE_CLASS
))
518 /* Attempt to determine real type of object. */
519 real_type
= value_rtti_type (val
, &full
, &top
, &using_enc
);
522 /* We have RTTI information, so use it. */
523 val
= value_full_object (val
, real_type
,
524 full
, top
, using_enc
);
525 fprintf_filtered (stream
, "(%s%s) ",
526 TYPE_NAME (real_type
),
527 full
? "" : _(" [incomplete object]"));
528 /* Print out object: enclosing type is same as real_type if
530 val_print (value_enclosing_type (val
),
531 value_contents_for_printing (val
), 0,
532 value_address (val
), stream
, 0,
533 val
, &opts
, current_language
);
535 /* Note: When we look up RTTI entries, we don't get any
536 information on const or volatile attributes. */
538 else if (type
!= check_typedef (value_enclosing_type (val
)))
540 /* No RTTI information, so let's do our best. */
541 fprintf_filtered (stream
, "(%s ?) ",
542 TYPE_NAME (value_enclosing_type (val
)));
543 val_print (value_enclosing_type (val
),
544 value_contents_for_printing (val
), 0,
545 value_address (val
), stream
, 0,
546 val
, &opts
, current_language
);
549 /* Otherwise, we end up at the return outside this "if". */
552 val_print (val_type
, value_contents_for_printing (val
),
553 value_embedded_offset (val
),
556 val
, &opts
, current_language
);