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);
259 addr = unpack_pointer (type, valaddr + embedded_offset);
260 print_unpacked_pointer:
264 if (TYPE_CODE (elttype) == TYPE_CODE_FUNC)
266 /* Try to print what function it points to. */
267 print_function_pointer_address (options, gdbarch, addr, stream);
271 if (options->addressprint)
273 fputs_filtered (paddress (gdbarch, addr), stream);
277 /* For a pointer to a textual type, also print the string
278 pointed to, unless pointer is null. */
280 if (c_textual_element_type (unresolved_elttype,
285 fputs_filtered (" ", stream);
286 i = val_print_string (unresolved_elttype, NULL,
290 else if (cp_is_vtbl_member (type))
292 /* Print vtbl's nicely. */
293 CORE_ADDR vt_address = unpack_pointer (type,
296 struct minimal_symbol *msymbol =
297 lookup_minimal_symbol_by_pc (vt_address);
299 if ((msymbol != NULL)
300 && (vt_address == SYMBOL_VALUE_ADDRESS (msymbol)))
303 fputs_filtered (" ", stream);
304 fputs_filtered (" <", stream);
305 fputs_filtered (SYMBOL_PRINT_NAME (msymbol), stream);
306 fputs_filtered (">", stream);
310 if (vt_address && options->vtblprint)
312 struct value *vt_val;
313 struct symbol *wsym = (struct symbol *) NULL;
315 struct block *block = (struct block *) NULL;
319 fputs_filtered (" ", stream);
322 wsym = lookup_symbol (SYMBOL_LINKAGE_NAME (msymbol),
328 wtype = SYMBOL_TYPE (wsym);
332 wtype = unresolved_elttype;
334 vt_val = value_at (wtype, vt_address);
335 common_val_print (vt_val, stream, recurse + 1,
336 options, current_language);
339 fprintf_filtered (stream, "\n");
340 print_spaces_filtered (2 + 2 * recurse, stream);
348 case TYPE_CODE_UNION:
349 if (recurse && !options->unionprint)
351 fprintf_filtered (stream, "{...}");
355 case TYPE_CODE_STRUCT:
356 /*FIXME: Abstract this away. */
357 if (options->vtblprint && cp_is_vtbl_ptr_type (type))
359 /* Print the unmangled name if desired. */
360 /* Print vtable entry - we only get here if NOT using
361 -fvtable_thunks. (Otherwise, look under
363 int offset = (embedded_offset
364 + TYPE_FIELD_BITPOS (type,
365 VTBL_FNADDR_OFFSET) / 8);
366 struct type *field_type = TYPE_FIELD_TYPE (type,
369 = extract_typed_address (valaddr + offset, field_type);
371 print_function_pointer_address (options, gdbarch, addr, stream);
374 cp_print_value_fields_rtti (type, valaddr,
375 embedded_offset, address,
377 original_value, options,
382 if (options->format || options->output_format)
384 struct value_print_options opts = *options;
386 opts.format = (options->format ? options->format
387 : options->output_format);
388 val_print_scalar_formatted (type, valaddr, embedded_offset,
389 original_value, &opts, 0, stream);
393 val_print_type_code_int (type, valaddr + embedded_offset,
395 /* C and C++ has no single byte int type, char is used
396 instead. Since we don't know whether the value is really
397 intended to be used as an integer or a character, print
398 the character equivalent as well. */
399 if (c_textual_element_type (unresolved_type, options->format))
401 fputs_filtered (" ", stream);
402 LA_PRINT_CHAR (unpack_long (type, valaddr + embedded_offset),
403 unresolved_type, stream);
408 case TYPE_CODE_MEMBERPTR:
409 if (!options->format)
411 cp_print_class_member (valaddr + embedded_offset, type, stream, "&");
418 case TYPE_CODE_FLAGS:
420 case TYPE_CODE_METHOD:
422 case TYPE_CODE_RANGE:
424 case TYPE_CODE_DECFLOAT:
426 case TYPE_CODE_ERROR:
427 case TYPE_CODE_UNDEF:
428 case TYPE_CODE_COMPLEX:
431 generic_val_print (type, valaddr, embedded_offset, address,
432 stream, recurse, original_value, options,
440 c_value_print (struct value *val, struct ui_file *stream,
441 const struct value_print_options *options)
443 struct type *type, *real_type, *val_type;
444 int full, top, using_enc;
445 struct value_print_options opts = *options;
449 /* If it is a pointer, indicate what it points to.
451 Print type also if it is a reference.
453 C++: if it is a member pointer, we will take care
454 of that when we print it. */
456 /* Preserve the original type before stripping typedefs. We prefer
457 to pass down the original type when possible, but for local
458 checks it is better to look past the typedefs. */
459 val_type = value_type (val);
460 type = check_typedef (val_type);
462 if (TYPE_CODE (type) == TYPE_CODE_PTR
463 || TYPE_CODE (type) == TYPE_CODE_REF)
465 /* Hack: remove (char *) for char strings. Their
466 type is indicated by the quoted string anyway.
467 (Don't use c_textual_element_type here; quoted strings
468 are always exactly (char *), (wchar_t *), or the like. */
469 if (TYPE_CODE (val_type) == TYPE_CODE_PTR
470 && TYPE_NAME (val_type) == NULL
471 && TYPE_NAME (TYPE_TARGET_TYPE (val_type)) != NULL
472 && (strcmp (TYPE_NAME (TYPE_TARGET_TYPE (val_type)),
474 || textual_name (TYPE_NAME (TYPE_TARGET_TYPE (val_type)))))
478 else if (options->objectprint
479 && (TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_CLASS))
482 if (TYPE_CODE(type) == TYPE_CODE_REF)
484 /* Copy value, change to pointer, so we don't get an
485 error about a non-pointer type in
486 value_rtti_target_type. */
487 struct value *temparg;
488 temparg=value_copy(val);
489 deprecated_set_value_type
490 (temparg, lookup_pointer_type (TYPE_TARGET_TYPE (type)));
493 /* Pointer to class, check real type of object. */
494 fprintf_filtered (stream, "(");
496 if (value_entirely_available (val))
498 real_type = value_rtti_indirect_type (val, &full, &top,
502 /* RTTI entry found. */
505 /* Need to adjust pointer value. */
506 val = value_from_pointer (type, value_as_address (val) - top);
508 /* Note: When we look up RTTI entries, we don't get
509 any information on const or volatile
513 type_print (type, "", stream, -1);
514 fprintf_filtered (stream, ") ");
520 fprintf_filtered (stream, "(");
521 type_print (value_type (val), "", stream, -1);
522 fprintf_filtered (stream, ") ");
526 if (!value_initialized (val))
527 fprintf_filtered (stream, " [uninitialized] ");
529 if (options->objectprint && (TYPE_CODE (type) == TYPE_CODE_CLASS))
531 /* Attempt to determine real type of object. */
532 real_type = value_rtti_type (val, &full, &top, &using_enc);
535 /* We have RTTI information, so use it. */
536 val = value_full_object (val, real_type,
537 full, top, using_enc);
538 fprintf_filtered (stream, "(%s%s) ",
539 TYPE_NAME (real_type),
540 full ? "" : _(" [incomplete object]"));
541 /* Print out object: enclosing type is same as real_type if
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);
548 /* Note: When we look up RTTI entries, we don't get any
549 information on const or volatile attributes. */
551 else if (type != check_typedef (value_enclosing_type (val)))
553 /* No RTTI information, so let's do our best. */
554 fprintf_filtered (stream, "(%s ?) ",
555 TYPE_NAME (value_enclosing_type (val)));
556 val_print (value_enclosing_type (val),
557 value_contents_for_printing (val), 0,
558 value_address (val), stream, 0,
559 val, &opts, current_language);
562 /* Otherwise, we end up at the return outside this "if". */
565 val_print (val_type, value_contents_for_printing (val),
566 value_embedded_offset (val),
569 val, &opts, current_language);