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
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, CORE_ADDR address,
40 struct ui_file *stream, int addressprint)
42 CORE_ADDR func_addr = gdbarch_convert_from_func_ptr_addr (gdbarch, address,
45 /* If the function pointer is represented by a description, print the
46 address of the description. */
47 if (addressprint && func_addr != address)
49 fputs_filtered ("@", stream);
50 fputs_filtered (paddress (gdbarch, address), stream);
51 fputs_filtered (": ", stream);
53 print_address_demangle (gdbarch, func_addr, stream, demangle);
57 /* A helper for c_textual_element_type. This checks the name of the
58 typedef. This is bogus but it isn't apparent that the compiler
59 provides us the help we may need. */
62 textual_name (const char *name)
64 return (!strcmp (name, "wchar_t")
65 || !strcmp (name, "char16_t")
66 || !strcmp (name, "char32_t"));
69 /* Apply a heuristic to decide whether an array of TYPE or a pointer
70 to TYPE should be printed as a textual string. Return non-zero if
71 it should, or zero if it should be treated as an array of integers
72 or pointer to integers. FORMAT is the current format letter,
75 We guess that "char" is a character. Explicitly signed and
76 unsigned character types are also characters. Integer data from
77 vector types is not. The user can override this by using the /s
81 c_textual_element_type (struct type *type, char format)
83 struct type *true_type, *iter_type;
85 if (format != 0 && format != 's')
88 /* We also rely on this for its side effect of setting up all the
90 true_type = check_typedef (type);
92 /* TYPE_CODE_CHAR is always textual. */
93 if (TYPE_CODE (true_type) == TYPE_CODE_CHAR)
96 /* Any other character-like types must be integral. */
97 if (TYPE_CODE (true_type) != TYPE_CODE_INT)
100 /* We peel typedefs one by one, looking for a match. */
104 /* Check the name of the type. */
105 if (TYPE_NAME (iter_type) && textual_name (TYPE_NAME (iter_type)))
108 if (TYPE_CODE (iter_type) != TYPE_CODE_TYPEDEF)
111 /* Peel a single typedef. If the typedef doesn't have a target
112 type, we use check_typedef and hope the result is ok -- it
113 might be for C++, where wchar_t is a built-in type. */
114 if (TYPE_TARGET_TYPE (iter_type))
115 iter_type = TYPE_TARGET_TYPE (iter_type);
117 iter_type = check_typedef (iter_type);
122 /* Print this as a string if we can manage it. For now, no
123 wide character support. */
124 if (TYPE_CODE (true_type) == TYPE_CODE_INT
125 && TYPE_LENGTH (true_type) == 1)
130 /* If a one-byte TYPE_CODE_INT is missing the not-a-character
131 flag, then we treat it as text; otherwise, we assume it's
132 being used as data. */
133 if (TYPE_CODE (true_type) == TYPE_CODE_INT
134 && TYPE_LENGTH (true_type) == 1
135 && !TYPE_NOTTEXT (true_type))
143 /* Print data of type TYPE located at VALADDR (within GDB), which came from
144 the inferior at address ADDRESS, onto stdio stream STREAM according to
145 OPTIONS. The data at VALADDR is in target byte order.
147 If the data are a string pointer, returns the number of string characters
151 c_val_print (struct type *type, const gdb_byte *valaddr, int embedded_offset,
152 CORE_ADDR address, 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, options->format)
189 && value_bits_valid (original_value,
190 TARGET_CHAR_BIT * embedded_offset,
191 TARGET_CHAR_BIT * TYPE_LENGTH (type)))
193 /* If requested, look for the first null char and only print
194 elements up to it. */
195 if (options->stop_print_at_null)
197 unsigned int temp_len;
201 && temp_len < options->print_max
202 && extract_unsigned_integer (valaddr + embedded_offset
204 eltlen, byte_order) != 0);
210 LA_PRINT_STRING (stream, unresolved_elttype,
211 valaddr + embedded_offset, len,
217 fprintf_filtered (stream, "{");
218 /* If this is a virtual function table, print the 0th
219 entry specially, and the rest of the members normally. */
220 if (cp_is_vtbl_ptr_type (elttype))
223 fprintf_filtered (stream, _("%d vtable entries"), len - 1);
229 val_print_array_elements (type, valaddr + embedded_offset,
230 address + embedded_offset, stream,
231 recurse, original_value, options, i);
232 fprintf_filtered (stream, "}");
236 /* Array of unspecified length: treat like pointer to first elt. */
238 goto print_unpacked_pointer;
240 case TYPE_CODE_MEMBERPTR:
243 print_scalar_formatted (valaddr + embedded_offset, type,
247 cp_print_class_member (valaddr + embedded_offset, type, stream, "&");
250 case TYPE_CODE_METHODPTR:
251 cplus_print_method_ptr (valaddr + embedded_offset, type, stream);
255 if (options->format && options->format != 's')
257 print_scalar_formatted (valaddr + embedded_offset, type,
261 if (options->vtblprint && cp_is_vtbl_ptr_type (type))
263 /* Print the unmangled name if desired. */
264 /* Print vtable entry - we only get here if we ARE using
265 -fvtable_thunks. (Otherwise, look under TYPE_CODE_STRUCT.) */
267 = extract_typed_address (valaddr + embedded_offset, type);
269 print_function_pointer_address (gdbarch, addr, stream,
270 options->addressprint);
273 unresolved_elttype = TYPE_TARGET_TYPE (type);
274 elttype = check_typedef (unresolved_elttype);
276 addr = unpack_pointer (type, valaddr + embedded_offset);
277 print_unpacked_pointer:
279 if (TYPE_CODE (elttype) == TYPE_CODE_FUNC)
281 /* Try to print what function it points to. */
282 print_function_pointer_address (gdbarch, addr, stream,
283 options->addressprint);
284 /* Return value is irrelevant except for string pointers. */
288 if (options->addressprint)
289 fputs_filtered (paddress (gdbarch, addr), stream);
291 /* For a pointer to a textual type, also print the string
292 pointed to, unless pointer is null. */
294 if (c_textual_element_type (unresolved_elttype, options->format)
297 i = val_print_string (unresolved_elttype, NULL, addr, -1, stream,
300 else if (cp_is_vtbl_member (type))
302 /* print vtbl's nicely */
303 CORE_ADDR vt_address = unpack_pointer (type, valaddr + embedded_offset);
305 struct minimal_symbol *msymbol =
306 lookup_minimal_symbol_by_pc (vt_address);
307 if ((msymbol != NULL)
308 && (vt_address == SYMBOL_VALUE_ADDRESS (msymbol)))
310 fputs_filtered (" <", stream);
311 fputs_filtered (SYMBOL_PRINT_NAME (msymbol), stream);
312 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 wsym = lookup_symbol (SYMBOL_LINKAGE_NAME (msymbol), block,
324 VAR_DOMAIN, &is_this_fld);
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, options,
339 fprintf_filtered (stream, "\n");
340 print_spaces_filtered (2 + 2 * recurse, stream);
345 /* Return number of characters printed, including the terminating
346 '\0' if we reached the end. val_print_string takes care including
347 the terminating '\0' if necessary. */
353 elttype = check_typedef (TYPE_TARGET_TYPE (type));
354 if (options->addressprint)
357 = extract_typed_address (valaddr + embedded_offset, type);
359 fprintf_filtered (stream, "@");
360 fputs_filtered (paddress (gdbarch, addr), stream);
361 if (options->deref_ref)
362 fputs_filtered (": ", stream);
364 /* De-reference the reference. */
365 if (options->deref_ref)
367 if (TYPE_CODE (elttype) != TYPE_CODE_UNDEF)
369 struct value *deref_val =
371 (TYPE_TARGET_TYPE (type),
372 unpack_pointer (type, valaddr + embedded_offset));
374 common_val_print (deref_val, stream, recurse, options,
378 fputs_filtered ("???", stream);
382 case TYPE_CODE_UNION:
383 if (recurse && !options->unionprint)
385 fprintf_filtered (stream, "{...}");
389 case TYPE_CODE_STRUCT:
390 /*FIXME: Abstract this away */
391 if (options->vtblprint && cp_is_vtbl_ptr_type (type))
393 /* Print the unmangled name if desired. */
394 /* Print vtable entry - we only get here if NOT using
395 -fvtable_thunks. (Otherwise, look under TYPE_CODE_PTR.) */
396 int offset = (embedded_offset +
397 TYPE_FIELD_BITPOS (type, VTBL_FNADDR_OFFSET) / 8);
398 struct type *field_type = TYPE_FIELD_TYPE (type, VTBL_FNADDR_OFFSET);
400 = extract_typed_address (valaddr + offset, field_type);
402 print_function_pointer_address (gdbarch, addr, stream,
403 options->addressprint);
406 cp_print_value_fields_rtti (type, valaddr,
407 embedded_offset, address, stream,
408 recurse, original_value, options, NULL, 0);
414 print_scalar_formatted (valaddr + embedded_offset, type,
418 len = TYPE_NFIELDS (type);
419 val = unpack_long (type, valaddr + embedded_offset);
420 for (i = 0; i < len; i++)
423 if (val == TYPE_FIELD_BITPOS (type, i))
430 fputs_filtered (TYPE_FIELD_NAME (type, i), stream);
434 print_longest (stream, 'd', 0, val);
438 case TYPE_CODE_FLAGS:
440 print_scalar_formatted (valaddr + embedded_offset, type,
443 val_print_type_code_flags (type, valaddr + embedded_offset, stream);
447 case TYPE_CODE_METHOD:
450 print_scalar_formatted (valaddr + embedded_offset, type,
454 /* FIXME, we should consider, at least for ANSI C language, eliminating
455 the distinction made between FUNCs and POINTERs to FUNCs. */
456 fprintf_filtered (stream, "{");
457 type_print (type, "", stream, -1);
458 fprintf_filtered (stream, "} ");
459 /* Try to print what function it points to, and its address. */
460 print_address_demangle (gdbarch, address, stream, demangle);
464 if (options->format || options->output_format)
466 struct value_print_options opts = *options;
467 opts.format = (options->format ? options->format
468 : options->output_format);
469 print_scalar_formatted (valaddr + embedded_offset, type,
474 val = unpack_long (type, valaddr + embedded_offset);
476 fputs_filtered ("false", stream);
478 fputs_filtered ("true", stream);
480 print_longest (stream, 'd', 0, val);
484 case TYPE_CODE_RANGE:
485 /* FIXME: create_range_type does not set the unsigned bit in a
486 range type (I think it probably should copy it from the target
487 type), so we won't print values which are too large to
488 fit in a signed integer correctly. */
489 /* FIXME: Doesn't handle ranges of enums correctly. (Can't just
490 print with the target type, though, because the size of our type
491 and the target type might differ). */
495 if (options->format || options->output_format)
497 struct value_print_options opts = *options;
499 opts.format = (options->format ? options->format
500 : options->output_format);
501 print_scalar_formatted (valaddr + embedded_offset, type,
506 val_print_type_code_int (type, valaddr + embedded_offset, stream);
507 /* C and C++ has no single byte int type, char is used instead.
508 Since we don't know whether the value is really intended to
509 be used as an integer or a character, print the character
510 equivalent as well. */
511 if (c_textual_element_type (unresolved_type, options->format))
513 fputs_filtered (" ", stream);
514 LA_PRINT_CHAR ((unsigned char) unpack_long (type, valaddr + embedded_offset),
515 unresolved_type, stream);
521 if (options->format || options->output_format)
523 struct value_print_options opts = *options;
524 opts.format = (options->format ? options->format
525 : options->output_format);
526 print_scalar_formatted (valaddr + embedded_offset, type,
531 val = unpack_long (type, valaddr + embedded_offset);
532 if (TYPE_UNSIGNED (type))
533 fprintf_filtered (stream, "%u", (unsigned int) val);
535 fprintf_filtered (stream, "%d", (int) val);
536 fputs_filtered (" ", stream);
537 LA_PRINT_CHAR ((unsigned char) val, unresolved_type, stream);
544 print_scalar_formatted (valaddr + embedded_offset, type,
549 print_floating (valaddr + embedded_offset, type, stream);
553 case TYPE_CODE_DECFLOAT:
555 print_scalar_formatted (valaddr + embedded_offset, type,
558 print_decimal_floating (valaddr + embedded_offset, type, stream);
562 fprintf_filtered (stream, "void");
565 case TYPE_CODE_ERROR:
566 fprintf_filtered (stream, "%s", TYPE_ERROR_NAME (type));
569 case TYPE_CODE_UNDEF:
570 /* This happens (without TYPE_FLAG_STUB set) on systems which don't use
571 dbx xrefs (NO_DBX_XREFS in gcc) if a file has a "struct foo *bar"
572 and no complete type for struct foo in that file. */
573 fprintf_filtered (stream, _("<incomplete type>"));
576 case TYPE_CODE_COMPLEX:
578 print_scalar_formatted (valaddr + embedded_offset,
579 TYPE_TARGET_TYPE (type),
582 print_floating (valaddr + embedded_offset, TYPE_TARGET_TYPE (type),
584 fprintf_filtered (stream, " + ");
586 print_scalar_formatted (valaddr + embedded_offset
587 + TYPE_LENGTH (TYPE_TARGET_TYPE (type)),
588 TYPE_TARGET_TYPE (type),
591 print_floating (valaddr + embedded_offset
592 + TYPE_LENGTH (TYPE_TARGET_TYPE (type)),
593 TYPE_TARGET_TYPE (type),
595 fprintf_filtered (stream, " * I");
599 error (_("Invalid C/C++ type code %d in symbol table."), TYPE_CODE (type));
606 c_value_print (struct value *val, struct ui_file *stream,
607 const struct value_print_options *options)
609 struct type *type, *real_type, *val_type;
610 int full, top, using_enc;
611 struct value_print_options opts = *options;
615 /* If it is a pointer, indicate what it points to.
617 Print type also if it is a reference.
619 C++: if it is a member pointer, we will take care
620 of that when we print it. */
622 /* Preserve the original type before stripping typedefs. We prefer
623 to pass down the original type when possible, but for local
624 checks it is better to look past the typedefs. */
625 val_type = value_type (val);
626 type = check_typedef (val_type);
628 if (TYPE_CODE (type) == TYPE_CODE_PTR
629 || TYPE_CODE (type) == TYPE_CODE_REF)
631 /* Hack: remove (char *) for char strings. Their
632 type is indicated by the quoted string anyway.
633 (Don't use c_textual_element_type here; quoted strings
634 are always exactly (char *), (wchar_t *), or the like. */
635 if (TYPE_CODE (val_type) == TYPE_CODE_PTR
636 && TYPE_NAME (val_type) == NULL
637 && TYPE_NAME (TYPE_TARGET_TYPE (val_type)) != NULL
638 && (strcmp (TYPE_NAME (TYPE_TARGET_TYPE (val_type)), "char") == 0
639 || textual_name (TYPE_NAME (TYPE_TARGET_TYPE (val_type)))))
643 else if (options->objectprint
644 && (TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_CLASS))
647 if (TYPE_CODE(type) == TYPE_CODE_REF)
649 /* Copy value, change to pointer, so we don't get an
650 * error about a non-pointer type in value_rtti_target_type
652 struct value *temparg;
653 temparg=value_copy(val);
654 deprecated_set_value_type (temparg, lookup_pointer_type (TYPE_TARGET_TYPE(type)));
657 /* Pointer to class, check real type of object */
658 fprintf_filtered (stream, "(");
659 real_type = value_rtti_target_type (val, &full, &top, &using_enc);
662 /* RTTI entry found */
663 if (TYPE_CODE (type) == TYPE_CODE_PTR)
665 /* create a pointer type pointing to the real type */
666 type = lookup_pointer_type (real_type);
670 /* create a reference type referencing the real type */
671 type = lookup_reference_type (real_type);
673 /* JYG: Need to adjust pointer value. */
674 /* NOTE: cagney/2005-01-02: THIS IS BOGUS. */
675 value_contents_writeable (val)[0] -= top;
677 /* Note: When we look up RTTI entries, we don't get any
678 information on const or volatile attributes */
680 type_print (type, "", stream, -1);
681 fprintf_filtered (stream, ") ");
687 fprintf_filtered (stream, "(");
688 type_print (value_type (val), "", stream, -1);
689 fprintf_filtered (stream, ") ");
693 if (!value_initialized (val))
694 fprintf_filtered (stream, " [uninitialized] ");
696 if (options->objectprint && (TYPE_CODE (type) == TYPE_CODE_CLASS))
698 /* Attempt to determine real type of object */
699 real_type = value_rtti_type (val, &full, &top, &using_enc);
702 /* We have RTTI information, so use it */
703 val = value_full_object (val, real_type, full, top, using_enc);
704 fprintf_filtered (stream, "(%s%s) ",
705 TYPE_NAME (real_type),
706 full ? "" : _(" [incomplete object]"));
707 /* Print out object: enclosing type is same as real_type if full */
708 return val_print (value_enclosing_type (val),
709 value_contents_for_printing (val), 0,
710 value_address (val), stream, 0,
711 val, &opts, current_language);
712 /* Note: When we look up RTTI entries, we don't get any information on
713 const or volatile attributes */
715 else if (type != check_typedef (value_enclosing_type (val)))
717 /* No RTTI information, so let's do our best */
718 fprintf_filtered (stream, "(%s ?) ",
719 TYPE_NAME (value_enclosing_type (val)));
720 return val_print (value_enclosing_type (val),
721 value_contents_for_printing (val), 0,
722 value_address (val), stream, 0,
723 val, &opts, current_language);
725 /* Otherwise, we end up at the return outside this "if" */
728 return val_print (val_type, value_contents_for_printing (val),
729 value_embedded_offset (val),
732 val, &opts, current_language);