1 /* Language independent support for printing types for GDB, the GNU debugger.
3 Copyright (C) 1986-2019 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21 #include "gdb_obstack.h"
22 #include "bfd.h" /* Binary File Description */
25 #include "expression.h"
33 #include "typeprint.h"
36 #include "cli/cli-utils.h"
37 #include "extension.h"
38 #include "completer.h"
40 const struct type_print_options type_print_raw_options
=
43 1, /* print_methods */
44 1, /* print_typedefs */
45 0, /* print_offsets */
46 0, /* print_nested_type_limit */
47 NULL
, /* local_typedefs */
48 NULL
, /* global_table */
49 NULL
/* global_printers */
52 /* The default flags for 'ptype' and 'whatis'. */
54 static struct type_print_options default_ptype_flags
=
57 1, /* print_methods */
58 1, /* print_typedefs */
59 0, /* print_offsets */
60 0, /* print_nested_type_limit */
61 NULL
, /* local_typedefs */
62 NULL
, /* global_table */
63 NULL
/* global_printers */
68 /* See typeprint.h. */
70 const int print_offset_data::indentation
= 23;
73 /* See typeprint.h. */
76 print_offset_data::maybe_print_hole (struct ui_file
*stream
,
80 /* We check for END_BITPOS > 0 because there is a specific
81 scenario when END_BITPOS can be zero and BITPOS can be >
82 0: when we are dealing with a struct/class with a virtual method.
83 Because of the vtable, the first field of the struct/class will
84 have an offset of sizeof (void *) (the size of the vtable). If
85 we do not check for END_BITPOS > 0 here, GDB will report
86 a hole before the first field, which is not accurate. */
87 if (end_bitpos
> 0 && end_bitpos
< bitpos
)
89 /* If END_BITPOS is smaller than the current type's
90 bitpos, it means there's a hole in the struct, so we report
92 unsigned int hole
= bitpos
- end_bitpos
;
93 unsigned int hole_byte
= hole
/ TARGET_CHAR_BIT
;
94 unsigned int hole_bit
= hole
% TARGET_CHAR_BIT
;
97 fprintf_filtered (stream
, "/* XXX %2u-bit %s */\n", hole_bit
,
101 fprintf_filtered (stream
, "/* XXX %2u-byte %s */\n", hole_byte
,
106 /* See typeprint.h. */
109 print_offset_data::update (struct type
*type
, unsigned int field_idx
,
110 struct ui_file
*stream
)
112 if (field_is_static (&TYPE_FIELD (type
, field_idx
)))
114 print_spaces_filtered (indentation
, stream
);
118 struct type
*ftype
= check_typedef (TYPE_FIELD_TYPE (type
, field_idx
));
119 if (TYPE_CODE (type
) == TYPE_CODE_UNION
)
121 /* Since union fields don't have the concept of offsets, we just
122 print their sizes. */
123 fprintf_filtered (stream
, "/* %4s */",
124 pulongest (TYPE_LENGTH (ftype
)));
128 unsigned int bitpos
= TYPE_FIELD_BITPOS (type
, field_idx
);
129 unsigned int fieldsize_byte
= TYPE_LENGTH (ftype
);
130 unsigned int fieldsize_bit
= fieldsize_byte
* TARGET_CHAR_BIT
;
132 maybe_print_hole (stream
, bitpos
, "hole");
134 if (TYPE_FIELD_PACKED (type
, field_idx
)
135 || offset_bitpos
% TARGET_CHAR_BIT
!= 0)
137 /* We're dealing with a bitfield. Print the bit offset. */
138 fieldsize_bit
= TYPE_FIELD_BITSIZE (type
, field_idx
);
140 unsigned real_bitpos
= bitpos
+ offset_bitpos
;
142 fprintf_filtered (stream
, "/* %4u:%2u", real_bitpos
/ TARGET_CHAR_BIT
,
143 real_bitpos
% TARGET_CHAR_BIT
);
147 /* The position of the field, relative to the beginning of the
149 fprintf_filtered (stream
, "/* %4u",
150 (bitpos
+ offset_bitpos
) / TARGET_CHAR_BIT
);
152 fprintf_filtered (stream
, " ");
155 fprintf_filtered (stream
, " | %4u */", fieldsize_byte
);
157 end_bitpos
= bitpos
+ fieldsize_bit
;
160 /* See typeprint.h. */
163 print_offset_data::finish (struct type
*type
, int level
,
164 struct ui_file
*stream
)
166 unsigned int bitpos
= TYPE_LENGTH (type
) * TARGET_CHAR_BIT
;
167 maybe_print_hole (stream
, bitpos
, "padding");
169 fputs_filtered ("\n", stream
);
170 print_spaces_filtered (level
+ 4 + print_offset_data::indentation
, stream
);
171 fprintf_filtered (stream
, "/* total size (bytes): %4s */\n",
172 pulongest (TYPE_LENGTH (type
)));
177 /* A hash function for a typedef_field. */
180 hash_typedef_field (const void *p
)
182 const struct decl_field
*tf
= (const struct decl_field
*) p
;
183 struct type
*t
= check_typedef (tf
->type
);
185 return htab_hash_string (TYPE_SAFE_NAME (t
));
188 /* An equality function for a typedef field. */
191 eq_typedef_field (const void *a
, const void *b
)
193 const struct decl_field
*tfa
= (const struct decl_field
*) a
;
194 const struct decl_field
*tfb
= (const struct decl_field
*) b
;
196 return types_equal (tfa
->type
, tfb
->type
);
199 /* See typeprint.h. */
202 typedef_hash_table::recursively_update (struct type
*t
)
206 for (i
= 0; i
< TYPE_TYPEDEF_FIELD_COUNT (t
); ++i
)
208 struct decl_field
*tdef
= &TYPE_TYPEDEF_FIELD (t
, i
);
211 slot
= htab_find_slot (m_table
, tdef
, INSERT
);
212 /* Only add a given typedef name once. Really this shouldn't
213 happen; but it is safe enough to do the updates breadth-first
214 and thus use the most specific typedef. */
219 /* Recurse into superclasses. */
220 for (i
= 0; i
< TYPE_N_BASECLASSES (t
); ++i
)
221 recursively_update (TYPE_BASECLASS (t
, i
));
224 /* See typeprint.h. */
227 typedef_hash_table::add_template_parameters (struct type
*t
)
231 for (i
= 0; i
< TYPE_N_TEMPLATE_ARGUMENTS (t
); ++i
)
233 struct decl_field
*tf
;
236 /* We only want type-valued template parameters in the hash. */
237 if (SYMBOL_CLASS (TYPE_TEMPLATE_ARGUMENT (t
, i
)) != LOC_TYPEDEF
)
240 tf
= XOBNEW (&m_storage
, struct decl_field
);
241 tf
->name
= SYMBOL_LINKAGE_NAME (TYPE_TEMPLATE_ARGUMENT (t
, i
));
242 tf
->type
= SYMBOL_TYPE (TYPE_TEMPLATE_ARGUMENT (t
, i
));
244 slot
= htab_find_slot (m_table
, tf
, INSERT
);
250 /* See typeprint.h. */
252 typedef_hash_table::typedef_hash_table ()
254 m_table
= htab_create_alloc (10, hash_typedef_field
, eq_typedef_field
,
255 NULL
, xcalloc
, xfree
);
258 /* Free a typedef field table. */
260 typedef_hash_table::~typedef_hash_table ()
262 htab_delete (m_table
);
265 /* Helper function for typedef_hash_table::copy. */
268 copy_typedef_hash_element (void **slot
, void *nt
)
270 htab_t new_table
= (htab_t
) nt
;
273 new_slot
= htab_find_slot (new_table
, *slot
, INSERT
);
274 if (*new_slot
== NULL
)
280 /* See typeprint.h. */
282 typedef_hash_table::typedef_hash_table (const typedef_hash_table
&table
)
284 m_table
= htab_create_alloc (10, hash_typedef_field
, eq_typedef_field
,
285 NULL
, xcalloc
, xfree
);
286 htab_traverse_noresize (table
.m_table
, copy_typedef_hash_element
,
290 /* Look up the type T in the global typedef hash. If it is found,
291 return the typedef name. If it is not found, apply the
292 type-printers, if any, given by start_script_type_printers and return the
293 result. A NULL return means that the name was not found. */
296 typedef_hash_table::find_global_typedef (const struct type_print_options
*flags
,
301 struct decl_field tf
, *new_tf
;
303 if (flags
->global_typedefs
== NULL
)
309 slot
= htab_find_slot (flags
->global_typedefs
->m_table
, &tf
, INSERT
);
312 new_tf
= (struct decl_field
*) *slot
;
316 /* Put an entry into the hash table now, in case
317 apply_ext_lang_type_printers recurses. */
318 new_tf
= XOBNEW (&flags
->global_typedefs
->m_storage
, struct decl_field
);
324 applied
= apply_ext_lang_type_printers (flags
->global_printers
, t
);
329 = (const char *) obstack_copy0 (&flags
->global_typedefs
->m_storage
,
330 applied
, strlen (applied
));
337 /* See typeprint.h. */
340 typedef_hash_table::find_typedef (const struct type_print_options
*flags
,
343 if (flags
->local_typedefs
!= NULL
)
345 struct decl_field tf
, *found
;
349 found
= (struct decl_field
*) htab_find (flags
->local_typedefs
->m_table
,
356 return find_global_typedef (flags
, t
);
361 /* Print a description of a type in the format of a
362 typedef for the current language.
363 NEW is the new name for a type TYPE. */
366 typedef_print (struct type
*type
, struct symbol
*newobj
, struct ui_file
*stream
)
368 LA_PRINT_TYPEDEF (type
, newobj
, stream
);
371 /* The default way to print a typedef. */
374 default_print_typedef (struct type
*type
, struct symbol
*new_symbol
,
375 struct ui_file
*stream
)
377 error (_("Language not supported."));
380 /* Print a description of a type TYPE in the form of a declaration of a
381 variable named VARSTRING. (VARSTRING is demangled if necessary.)
382 Output goes to STREAM (via stdio).
383 If SHOW is positive, we show the contents of the outermost level
384 of structure even if there is a type name that could be used instead.
385 If SHOW is negative, we never show the details of elements' types. */
388 type_print (struct type
*type
, const char *varstring
, struct ui_file
*stream
,
391 LA_PRINT_TYPE (type
, varstring
, stream
, show
, 0, &default_ptype_flags
);
394 /* Print TYPE to a string, returning it. The caller is responsible for
395 freeing the string. */
398 type_to_string (struct type
*type
)
404 type_print (type
, "", &stb
, -1);
405 return std::move (stb
.string ());
407 catch (const gdb_exception
&except
)
414 /* See typeprint.h. */
417 type_print_unknown_return_type (struct ui_file
*stream
)
419 fprintf_filtered (stream
, _("<unknown return type>"));
422 /* See typeprint.h. */
425 error_unknown_type (const char *sym_print_name
)
427 error (_("'%s' has unknown type; cast it to its declared type"),
431 /* Print type of EXP, or last thing in value history if EXP == NULL.
432 show is passed to type_print. */
435 whatis_exp (const char *exp
, int show
)
438 struct type
*real_type
= NULL
;
443 struct value_print_options opts
;
444 struct type_print_options flags
= default_ptype_flags
;
452 for (++exp
; *exp
&& !isspace (*exp
); ++exp
)
460 flags
.print_methods
= 0;
463 flags
.print_methods
= 1;
466 flags
.print_typedefs
= 0;
469 flags
.print_typedefs
= 1;
473 /* Filter out languages which don't implement the
476 && (current_language
->la_language
== language_c
477 || current_language
->la_language
== language_cplus
478 || current_language
->la_language
== language_rust
))
480 flags
.print_offsets
= 1;
481 flags
.print_typedefs
= 0;
482 flags
.print_methods
= 0;
487 error (_("unrecognized flag '%c'"), *exp
);
492 if (!*exp
&& !seen_one
)
493 error (_("flag expected"));
495 error (_("expected space after format"));
496 exp
= skip_spaces (exp
);
499 expression_up expr
= parse_expression (exp
);
501 /* The behavior of "whatis" depends on whether the user
502 expression names a type directly, or a language expression
503 (including variable names). If the former, then "whatis"
504 strips one level of typedefs, only. If an expression,
505 "whatis" prints the type of the expression without stripping
506 any typedef level. "ptype" always strips all levels of
508 if (show
== -1 && expr
->elts
[0].opcode
== OP_TYPE
)
510 /* The user expression names a type directly. */
511 type
= expr
->elts
[1].type
;
513 /* If this is a typedef, then find its immediate target.
514 Use check_typedef to resolve stubs, but ignore its result
515 because we do not want to dig past all typedefs. */
516 check_typedef (type
);
517 if (TYPE_CODE (type
) == TYPE_CODE_TYPEDEF
)
518 type
= TYPE_TARGET_TYPE (type
);
520 /* If the expression is actually a type, then there's no
521 value to fetch the dynamic type from. */
526 /* The user expression names a type indirectly by naming an
527 object or expression of that type. Find that
528 indirectly-named type. */
529 val
= evaluate_type (expr
.get ());
530 type
= value_type (val
);
535 val
= access_value_history (0);
536 type
= value_type (val
);
539 get_user_print_options (&opts
);
540 if (val
!= NULL
&& opts
.objectprint
)
542 if (((TYPE_CODE (type
) == TYPE_CODE_PTR
) || TYPE_IS_REFERENCE (type
))
543 && (TYPE_CODE (TYPE_TARGET_TYPE (type
)) == TYPE_CODE_STRUCT
))
544 real_type
= value_rtti_indirect_type (val
, &full
, &top
, &using_enc
);
545 else if (TYPE_CODE (type
) == TYPE_CODE_STRUCT
)
546 real_type
= value_rtti_type (val
, &full
, &top
, &using_enc
);
549 if (flags
.print_offsets
550 && (TYPE_CODE (type
) == TYPE_CODE_STRUCT
551 || TYPE_CODE (type
) == TYPE_CODE_UNION
))
552 fprintf_filtered (gdb_stdout
, "/* offset | size */ ");
554 printf_filtered ("type = ");
556 std::unique_ptr
<typedef_hash_table
> table_holder
;
557 std::unique_ptr
<ext_lang_type_printers
> printer_holder
;
560 table_holder
.reset (new typedef_hash_table
);
561 flags
.global_typedefs
= table_holder
.get ();
563 printer_holder
.reset (new ext_lang_type_printers
);
564 flags
.global_printers
= printer_holder
.get ();
569 printf_filtered ("/* real type = ");
570 type_print (real_type
, "", gdb_stdout
, -1);
572 printf_filtered (" (incomplete object)");
573 printf_filtered (" */\n");
576 LA_PRINT_TYPE (type
, "", gdb_stdout
, show
, 0, &flags
);
577 printf_filtered ("\n");
581 whatis_command (const char *exp
, int from_tty
)
583 /* Most of the time users do not want to see all the fields
584 in a structure. If they do they can use the "ptype" command.
585 Hence the "-1" below. */
586 whatis_exp (exp
, -1);
589 /* TYPENAME is either the name of a type, or an expression. */
592 ptype_command (const char *type_name
, int from_tty
)
594 whatis_exp (type_name
, 1);
597 /* Print integral scalar data VAL, of type TYPE, onto stdio stream STREAM.
598 Used to print data from type structures in a specified type. For example,
599 array bounds may be characters or booleans in some languages, and this
600 allows the ranges to be printed in their "natural" form rather than as
601 decimal integer values.
603 FIXME: This is here simply because only the type printing routines
604 currently use it, and it wasn't clear if it really belonged somewhere
605 else (like printcmd.c). There are a lot of other gdb routines that do
606 something similar, but they are generally concerned with printing values
607 that come from the inferior in target byte order and target size. */
610 print_type_scalar (struct type
*type
, LONGEST val
, struct ui_file
*stream
)
615 type
= check_typedef (type
);
617 switch (TYPE_CODE (type
))
621 len
= TYPE_NFIELDS (type
);
622 for (i
= 0; i
< len
; i
++)
624 if (TYPE_FIELD_ENUMVAL (type
, i
) == val
)
631 fputs_filtered (TYPE_FIELD_NAME (type
, i
), stream
);
635 print_longest (stream
, 'd', 0, val
);
640 print_longest (stream
, TYPE_UNSIGNED (type
) ? 'u' : 'd', 0, val
);
644 LA_PRINT_CHAR ((unsigned char) val
, type
, stream
);
648 fprintf_filtered (stream
, val
? "TRUE" : "FALSE");
651 case TYPE_CODE_RANGE
:
652 print_type_scalar (TYPE_TARGET_TYPE (type
), val
, stream
);
655 case TYPE_CODE_UNDEF
:
657 case TYPE_CODE_ARRAY
:
658 case TYPE_CODE_STRUCT
:
659 case TYPE_CODE_UNION
:
664 case TYPE_CODE_STRING
:
665 case TYPE_CODE_ERROR
:
666 case TYPE_CODE_MEMBERPTR
:
667 case TYPE_CODE_METHODPTR
:
668 case TYPE_CODE_METHOD
:
670 case TYPE_CODE_RVALUE_REF
:
671 case TYPE_CODE_NAMESPACE
:
672 error (_("internal error: unhandled type in print_type_scalar"));
676 error (_("Invalid type code in symbol table."));
680 /* Dump details of a type specified either directly or indirectly.
681 Uses the same sort of type lookup mechanism as ptype_command()
682 and whatis_command(). */
685 maintenance_print_type (const char *type_name
, int from_tty
)
690 if (type_name
!= NULL
)
692 expression_up expr
= parse_expression (type_name
);
693 if (expr
->elts
[0].opcode
== OP_TYPE
)
695 /* The user expression names a type directly, just use that type. */
696 type
= expr
->elts
[1].type
;
700 /* The user expression may name a type indirectly by naming an
701 object of that type. Find that indirectly named type. */
702 val
= evaluate_type (expr
.get ());
703 type
= value_type (val
);
707 recursive_dump_type (type
, 0);
713 struct cmd_list_element
*setprinttypelist
;
715 struct cmd_list_element
*showprinttypelist
;
718 set_print_type (const char *arg
, int from_tty
)
721 "\"set print type\" must be followed by the name of a subcommand.\n");
722 help_list (setprintlist
, "set print type ", all_commands
, gdb_stdout
);
726 show_print_type (const char *args
, int from_tty
)
728 cmd_show_list (showprinttypelist
, from_tty
, "");
731 static int print_methods
= 1;
734 set_print_type_methods (const char *args
,
735 int from_tty
, struct cmd_list_element
*c
)
737 default_ptype_flags
.print_methods
= print_methods
;
741 show_print_type_methods (struct ui_file
*file
, int from_tty
,
742 struct cmd_list_element
*c
, const char *value
)
744 fprintf_filtered (file
, _("Printing of methods defined in a class in %s\n"),
748 static int print_typedefs
= 1;
751 set_print_type_typedefs (const char *args
,
752 int from_tty
, struct cmd_list_element
*c
)
754 default_ptype_flags
.print_typedefs
= print_typedefs
;
758 show_print_type_typedefs (struct ui_file
*file
, int from_tty
,
759 struct cmd_list_element
*c
, const char *value
)
761 fprintf_filtered (file
, _("Printing of typedefs defined in a class in %s\n"),
765 /* Limit on the number of nested type definitions to print or -1 to print
766 all nested type definitions in a class. By default, we do not print
767 nested definitions. */
769 static int print_nested_type_limit
= 0;
771 /* Set how many nested type definitions should be printed by the type
775 set_print_type_nested_types (const char *args
, int from_tty
,
776 struct cmd_list_element
*c
)
778 default_ptype_flags
.print_nested_type_limit
= print_nested_type_limit
;
781 /* Show how many nested type definitions the type printer will print. */
784 show_print_type_nested_types (struct ui_file
*file
, int from_tty
,
785 struct cmd_list_element
*c
, const char *value
)
789 fprintf_filtered (file
,
790 _("Will not print nested types defined in a class\n"));
794 fprintf_filtered (file
,
795 _("Will print %s nested types defined in a class\n"),
801 _initialize_typeprint (void)
803 struct cmd_list_element
*c
;
805 c
= add_com ("ptype", class_vars
, ptype_command
, _("\
806 Print definition of type TYPE.\n\
807 Usage: ptype[/FLAGS] TYPE | EXPRESSION\n\
808 Argument may be any type (for example a type name defined by typedef,\n\
809 or \"struct STRUCT-TAG\" or \"class CLASS-NAME\" or \"union UNION-TAG\"\n\
810 or \"enum ENUM-TAG\") or an expression.\n\
811 The selected stack frame's lexical context is used to look up the name.\n\
812 Contrary to \"whatis\", \"ptype\" always unrolls any typedefs.\n\
814 Available FLAGS are:\n\
815 /r print in \"raw\" form; do not substitute typedefs\n\
816 /m do not print methods defined in a class\n\
817 /M print methods defined in a class\n\
818 /t do not print typedefs defined in a class\n\
819 /T print typedefs defined in a class\n\
820 /o print offsets and sizes of fields in a struct (like pahole)\n"));
821 set_cmd_completer (c
, expression_completer
);
823 c
= add_com ("whatis", class_vars
, whatis_command
,
824 _("Print data type of expression EXP.\n\
825 Only one level of typedefs is unrolled. See also \"ptype\"."));
826 set_cmd_completer (c
, expression_completer
);
828 add_prefix_cmd ("type", no_class
, show_print_type
,
829 _("Generic command for showing type-printing settings."),
830 &showprinttypelist
, "show print type ", 0, &showprintlist
);
831 add_prefix_cmd ("type", no_class
, set_print_type
,
832 _("Generic command for setting how types print."),
833 &setprinttypelist
, "set print type ", 0, &setprintlist
);
835 add_setshow_boolean_cmd ("methods", no_class
, &print_methods
,
837 Set printing of methods defined in classes."), _("\
838 Show printing of methods defined in classes."), NULL
,
839 set_print_type_methods
,
840 show_print_type_methods
,
841 &setprinttypelist
, &showprinttypelist
);
842 add_setshow_boolean_cmd ("typedefs", no_class
, &print_typedefs
,
844 Set printing of typedefs defined in classes."), _("\
845 Show printing of typedefs defined in classes."), NULL
,
846 set_print_type_typedefs
,
847 show_print_type_typedefs
,
848 &setprinttypelist
, &showprinttypelist
);
850 add_setshow_zuinteger_unlimited_cmd ("nested-type-limit", no_class
,
851 &print_nested_type_limit
,
853 Set the number of recursive nested type definitions to print \
854 (\"unlimited\" or -1 to show all)."), _("\
855 Show the number of recursive nested type definitions to print."), NULL
,
856 set_print_type_nested_types
,
857 show_print_type_nested_types
,
858 &setprinttypelist
, &showprinttypelist
);
861 /* Print <not allocated> status to stream STREAM. */
864 val_print_not_allocated (struct ui_file
*stream
)
866 fprintf_filtered (stream
, _("<not allocated>"));
869 /* Print <not associated> status to stream STREAM. */
872 val_print_not_associated (struct ui_file
*stream
)
874 fprintf_filtered (stream
, _("<not associated>"));