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 (options
, gdbarch
, addr
, stream
);
254 unresolved_elttype
= TYPE_TARGET_TYPE (type
);
255 elttype
= check_typedef (unresolved_elttype
);
257 addr
= unpack_pointer (type
, valaddr
+ embedded_offset
);
258 print_unpacked_pointer
:
260 if (TYPE_CODE (elttype
) == TYPE_CODE_FUNC
)
262 /* Try to print what function it points to. */
263 print_function_pointer_address (options
, gdbarch
, addr
, stream
);
267 if (options
->addressprint
)
268 fputs_filtered (paddress (gdbarch
, addr
), stream
);
270 /* For a pointer to a textual type, also print the string
271 pointed to, unless pointer is null. */
273 if (c_textual_element_type (unresolved_elttype
,
277 i
= val_print_string (unresolved_elttype
, NULL
,
281 else if (cp_is_vtbl_member (type
))
283 /* Print vtbl's nicely. */
284 CORE_ADDR vt_address
= unpack_pointer (type
,
288 struct minimal_symbol
*msymbol
=
289 lookup_minimal_symbol_by_pc (vt_address
);
290 if ((msymbol
!= NULL
)
291 && (vt_address
== SYMBOL_VALUE_ADDRESS (msymbol
)))
293 fputs_filtered (" <", stream
);
294 fputs_filtered (SYMBOL_PRINT_NAME (msymbol
), stream
);
295 fputs_filtered (">", stream
);
297 if (vt_address
&& options
->vtblprint
)
299 struct value
*vt_val
;
300 struct symbol
*wsym
= (struct symbol
*) NULL
;
302 struct block
*block
= (struct block
*) NULL
;
306 wsym
= lookup_symbol (SYMBOL_LINKAGE_NAME (msymbol
),
312 wtype
= SYMBOL_TYPE (wsym
);
316 wtype
= unresolved_elttype
;
318 vt_val
= value_at (wtype
, vt_address
);
319 common_val_print (vt_val
, stream
, recurse
+ 1,
320 options
, current_language
);
323 fprintf_filtered (stream
, "\n");
324 print_spaces_filtered (2 + 2 * recurse
, stream
);
332 case TYPE_CODE_UNION
:
333 if (recurse
&& !options
->unionprint
)
335 fprintf_filtered (stream
, "{...}");
339 case TYPE_CODE_STRUCT
:
340 /*FIXME: Abstract this away. */
341 if (options
->vtblprint
&& cp_is_vtbl_ptr_type (type
))
343 /* Print the unmangled name if desired. */
344 /* Print vtable entry - we only get here if NOT using
345 -fvtable_thunks. (Otherwise, look under
347 int offset
= (embedded_offset
348 + TYPE_FIELD_BITPOS (type
,
349 VTBL_FNADDR_OFFSET
) / 8);
350 struct type
*field_type
= TYPE_FIELD_TYPE (type
,
353 = extract_typed_address (valaddr
+ offset
, field_type
);
355 print_function_pointer_address (options
, gdbarch
, addr
, stream
);
358 cp_print_value_fields_rtti (type
, valaddr
,
359 embedded_offset
, address
,
361 original_value
, options
,
366 if (options
->format
|| options
->output_format
)
368 struct value_print_options opts
= *options
;
370 opts
.format
= (options
->format
? options
->format
371 : options
->output_format
);
372 val_print_scalar_formatted (type
, valaddr
, embedded_offset
,
373 original_value
, &opts
, 0, stream
);
377 val_print_type_code_int (type
, valaddr
+ embedded_offset
,
379 /* C and C++ has no single byte int type, char is used
380 instead. Since we don't know whether the value is really
381 intended to be used as an integer or a character, print
382 the character equivalent as well. */
383 if (c_textual_element_type (unresolved_type
, options
->format
))
385 fputs_filtered (" ", stream
);
386 LA_PRINT_CHAR (unpack_long (type
, valaddr
+ embedded_offset
),
387 unresolved_type
, stream
);
392 case TYPE_CODE_MEMBERPTR
:
393 if (!options
->format
)
395 cp_print_class_member (valaddr
+ embedded_offset
, type
, stream
, "&");
402 case TYPE_CODE_FLAGS
:
404 case TYPE_CODE_METHOD
:
406 case TYPE_CODE_RANGE
:
408 case TYPE_CODE_DECFLOAT
:
410 case TYPE_CODE_ERROR
:
411 case TYPE_CODE_UNDEF
:
412 case TYPE_CODE_COMPLEX
:
415 generic_val_print (type
, valaddr
, embedded_offset
, address
,
416 stream
, recurse
, original_value
, options
,
424 c_value_print (struct value
*val
, struct ui_file
*stream
,
425 const struct value_print_options
*options
)
427 struct type
*type
, *real_type
, *val_type
;
428 int full
, top
, using_enc
;
429 struct value_print_options opts
= *options
;
433 /* If it is a pointer, indicate what it points to.
435 Print type also if it is a reference.
437 C++: if it is a member pointer, we will take care
438 of that when we print it. */
440 /* Preserve the original type before stripping typedefs. We prefer
441 to pass down the original type when possible, but for local
442 checks it is better to look past the typedefs. */
443 val_type
= value_type (val
);
444 type
= check_typedef (val_type
);
446 if (TYPE_CODE (type
) == TYPE_CODE_PTR
447 || TYPE_CODE (type
) == TYPE_CODE_REF
)
449 /* Hack: remove (char *) for char strings. Their
450 type is indicated by the quoted string anyway.
451 (Don't use c_textual_element_type here; quoted strings
452 are always exactly (char *), (wchar_t *), or the like. */
453 if (TYPE_CODE (val_type
) == TYPE_CODE_PTR
454 && TYPE_NAME (val_type
) == NULL
455 && TYPE_NAME (TYPE_TARGET_TYPE (val_type
)) != NULL
456 && (strcmp (TYPE_NAME (TYPE_TARGET_TYPE (val_type
)),
458 || textual_name (TYPE_NAME (TYPE_TARGET_TYPE (val_type
)))))
462 else if (options
->objectprint
463 && (TYPE_CODE (TYPE_TARGET_TYPE (type
)) == TYPE_CODE_CLASS
))
466 if (TYPE_CODE(type
) == TYPE_CODE_REF
)
468 /* Copy value, change to pointer, so we don't get an
469 error about a non-pointer type in
470 value_rtti_target_type. */
471 struct value
*temparg
;
472 temparg
=value_copy(val
);
473 deprecated_set_value_type
474 (temparg
, lookup_pointer_type (TYPE_TARGET_TYPE (type
)));
477 /* Pointer to class, check real type of object. */
478 fprintf_filtered (stream
, "(");
480 if (value_entirely_available (val
))
482 real_type
= value_rtti_indirect_type (val
, &full
, &top
,
486 /* RTTI entry found. */
489 /* Need to adjust pointer value. */
490 val
= value_from_pointer (type
, value_as_address (val
) - top
);
492 /* Note: When we look up RTTI entries, we don't get
493 any information on const or volatile
497 type_print (type
, "", stream
, -1);
498 fprintf_filtered (stream
, ") ");
504 fprintf_filtered (stream
, "(");
505 type_print (value_type (val
), "", stream
, -1);
506 fprintf_filtered (stream
, ") ");
510 if (!value_initialized (val
))
511 fprintf_filtered (stream
, " [uninitialized] ");
513 if (options
->objectprint
&& (TYPE_CODE (type
) == TYPE_CODE_CLASS
))
515 /* Attempt to determine real type of object. */
516 real_type
= value_rtti_type (val
, &full
, &top
, &using_enc
);
519 /* We have RTTI information, so use it. */
520 val
= value_full_object (val
, real_type
,
521 full
, top
, using_enc
);
522 fprintf_filtered (stream
, "(%s%s) ",
523 TYPE_NAME (real_type
),
524 full
? "" : _(" [incomplete object]"));
525 /* Print out object: enclosing type is same as real_type if
527 val_print (value_enclosing_type (val
),
528 value_contents_for_printing (val
), 0,
529 value_address (val
), stream
, 0,
530 val
, &opts
, current_language
);
532 /* Note: When we look up RTTI entries, we don't get any
533 information on const or volatile attributes. */
535 else if (type
!= check_typedef (value_enclosing_type (val
)))
537 /* No RTTI information, so let's do our best. */
538 fprintf_filtered (stream
, "(%s ?) ",
539 TYPE_NAME (value_enclosing_type (val
)));
540 val_print (value_enclosing_type (val
),
541 value_contents_for_printing (val
), 0,
542 value_address (val
), stream
, 0,
543 val
, &opts
, current_language
);
546 /* Otherwise, we end up at the return outside this "if". */
549 val_print (val_type
, value_contents_for_printing (val
),
550 value_embedded_offset (val
),
553 val
, &opts
, current_language
);