1 /* Language independent support for printing types for GDB, the GNU debugger.
3 Copyright (C) 1986-2017 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 extern void _initialize_typeprint (void);
42 static void ptype_command (char *, int);
44 static void whatis_command (char *, int);
46 static void whatis_exp (char *, int);
48 const struct type_print_options type_print_raw_options =
51 1, /* print_methods */
52 1, /* print_typedefs */
53 NULL, /* local_typedefs */
54 NULL, /* global_table */
55 NULL /* global_printers */
58 /* The default flags for 'ptype' and 'whatis'. */
60 static struct type_print_options default_ptype_flags =
63 1, /* print_methods */
64 1, /* print_typedefs */
65 NULL, /* local_typedefs */
66 NULL, /* global_table */
67 NULL /* global_printers */
72 /* A hash table holding typedef_field objects. This is more
73 complicated than an ordinary hash because it must also track the
74 lifetime of some -- but not all -- of the contained objects. */
76 struct typedef_hash_table
78 /* The actual hash table. */
81 /* Storage for typedef_field objects that must be synthesized. */
82 struct obstack storage;
85 /* A hash function for a typedef_field. */
88 hash_typedef_field (const void *p)
90 const struct typedef_field *tf = (const struct typedef_field *) p;
91 struct type *t = check_typedef (tf->type);
93 return htab_hash_string (TYPE_SAFE_NAME (t));
96 /* An equality function for a typedef field. */
99 eq_typedef_field (const void *a, const void *b)
101 const struct typedef_field *tfa = (const struct typedef_field *) a;
102 const struct typedef_field *tfb = (const struct typedef_field *) b;
104 return types_equal (tfa->type, tfb->type);
107 /* Add typedefs from T to the hash table TABLE. */
110 recursively_update_typedef_hash (struct typedef_hash_table *table,
118 for (i = 0; i < TYPE_TYPEDEF_FIELD_COUNT (t); ++i)
120 struct typedef_field *tdef = &TYPE_TYPEDEF_FIELD (t, i);
123 slot = htab_find_slot (table->table, tdef, INSERT);
124 /* Only add a given typedef name once. Really this shouldn't
125 happen; but it is safe enough to do the updates breadth-first
126 and thus use the most specific typedef. */
131 /* Recurse into superclasses. */
132 for (i = 0; i < TYPE_N_BASECLASSES (t); ++i)
133 recursively_update_typedef_hash (table, TYPE_BASECLASS (t, i));
136 /* Add template parameters from T to the typedef hash TABLE. */
139 add_template_parameters (struct typedef_hash_table *table, struct type *t)
146 for (i = 0; i < TYPE_N_TEMPLATE_ARGUMENTS (t); ++i)
148 struct typedef_field *tf;
151 /* We only want type-valued template parameters in the hash. */
152 if (SYMBOL_CLASS (TYPE_TEMPLATE_ARGUMENT (t, i)) != LOC_TYPEDEF)
155 tf = XOBNEW (&table->storage, struct typedef_field);
156 tf->name = SYMBOL_LINKAGE_NAME (TYPE_TEMPLATE_ARGUMENT (t, i));
157 tf->type = SYMBOL_TYPE (TYPE_TEMPLATE_ARGUMENT (t, i));
159 slot = htab_find_slot (table->table, tf, INSERT);
165 /* Create a new typedef-lookup hash table. */
167 struct typedef_hash_table *
168 create_typedef_hash (void)
170 struct typedef_hash_table *result;
172 result = XNEW (struct typedef_hash_table);
173 result->table = htab_create_alloc (10, hash_typedef_field, eq_typedef_field,
174 NULL, xcalloc, xfree);
175 obstack_init (&result->storage);
180 /* Free a typedef field table. */
183 free_typedef_hash (struct typedef_hash_table *table)
187 htab_delete (table->table);
188 obstack_free (&table->storage, NULL);
193 /* A cleanup for freeing a typedef_hash_table. */
196 do_free_typedef_hash (void *arg)
198 free_typedef_hash ((struct typedef_hash_table *) arg);
201 /* Return a new cleanup that frees TABLE. */
204 make_cleanup_free_typedef_hash (struct typedef_hash_table *table)
206 return make_cleanup (do_free_typedef_hash, table);
209 /* Helper function for copy_typedef_hash. */
212 copy_typedef_hash_element (void **slot, void *nt)
214 htab_t new_table = (htab_t) nt;
217 new_slot = htab_find_slot (new_table, *slot, INSERT);
218 if (*new_slot == NULL)
224 /* Copy a typedef hash. */
226 struct typedef_hash_table *
227 copy_typedef_hash (struct typedef_hash_table *table)
229 struct typedef_hash_table *result;
234 result = create_typedef_hash ();
235 htab_traverse_noresize (table->table, copy_typedef_hash_element,
240 /* A cleanup to free the global typedef hash. */
243 do_free_global_table (void *arg)
245 struct type_print_options *flags = (struct type_print_options *) arg;
247 free_typedef_hash (flags->global_typedefs);
248 free_ext_lang_type_printers (flags->global_printers);
251 /* Create the global typedef hash. */
253 static struct cleanup *
254 create_global_typedef_table (struct type_print_options *flags)
256 gdb_assert (flags->global_typedefs == NULL && flags->global_printers == NULL);
257 flags->global_typedefs = create_typedef_hash ();
258 flags->global_printers = start_ext_lang_type_printers ();
259 return make_cleanup (do_free_global_table, flags);
262 /* Look up the type T in the global typedef hash. If it is found,
263 return the typedef name. If it is not found, apply the
264 type-printers, if any, given by start_script_type_printers and return the
265 result. A NULL return means that the name was not found. */
268 find_global_typedef (const struct type_print_options *flags,
273 struct typedef_field tf, *new_tf;
275 if (flags->global_typedefs == NULL)
281 slot = htab_find_slot (flags->global_typedefs->table, &tf, INSERT);
284 new_tf = (struct typedef_field *) *slot;
288 /* Put an entry into the hash table now, in case
289 apply_ext_lang_type_printers recurses. */
290 new_tf = XOBNEW (&flags->global_typedefs->storage, struct typedef_field);
296 applied = apply_ext_lang_type_printers (flags->global_printers, t);
301 = (const char *) obstack_copy0 (&flags->global_typedefs->storage,
302 applied, strlen (applied));
309 /* Look up the type T in the typedef hash table in with FLAGS. If T
310 is in the table, return its short (class-relative) typedef name.
311 Otherwise return NULL. If the table is NULL, this always returns
315 find_typedef_in_hash (const struct type_print_options *flags, struct type *t)
317 if (flags->local_typedefs != NULL)
319 struct typedef_field tf, *found;
323 found = (struct typedef_field *) htab_find (flags->local_typedefs->table,
330 return find_global_typedef (flags, t);
335 /* Print a description of a type in the format of a
336 typedef for the current language.
337 NEW is the new name for a type TYPE. */
340 typedef_print (struct type *type, struct symbol *newobj, struct ui_file *stream)
342 LA_PRINT_TYPEDEF (type, newobj, stream);
345 /* The default way to print a typedef. */
348 default_print_typedef (struct type *type, struct symbol *new_symbol,
349 struct ui_file *stream)
351 error (_("Language not supported."));
354 /* Print a description of a type TYPE in the form of a declaration of a
355 variable named VARSTRING. (VARSTRING is demangled if necessary.)
356 Output goes to STREAM (via stdio).
357 If SHOW is positive, we show the contents of the outermost level
358 of structure even if there is a type name that could be used instead.
359 If SHOW is negative, we never show the details of elements' types. */
362 type_print (struct type *type, const char *varstring, struct ui_file *stream,
365 LA_PRINT_TYPE (type, varstring, stream, show, 0, &default_ptype_flags);
368 /* Print TYPE to a string, returning it. The caller is responsible for
369 freeing the string. */
372 type_to_string (struct type *type)
378 type_print (type, "", &stb, -1);
379 return std::move (stb.string ());
381 CATCH (except, RETURN_MASK_ALL)
389 /* Print type of EXP, or last thing in value history if EXP == NULL.
390 show is passed to type_print. */
393 whatis_exp (char *exp, int show)
396 struct cleanup *old_chain;
397 struct type *real_type = NULL;
402 struct value_print_options opts;
403 struct type_print_options flags = default_ptype_flags;
405 old_chain = make_cleanup (null_cleanup, NULL);
413 for (++exp; *exp && !isspace (*exp); ++exp)
421 flags.print_methods = 0;
424 flags.print_methods = 1;
427 flags.print_typedefs = 0;
430 flags.print_typedefs = 1;
433 error (_("unrecognized flag '%c'"), *exp);
438 if (!*exp && !seen_one)
439 error (_("flag expected"));
441 error (_("expected space after format"));
442 exp = skip_spaces (exp);
445 expression_up expr = parse_expression (exp);
446 val = evaluate_type (expr.get ());
449 val = access_value_history (0);
451 type = value_type (val);
453 get_user_print_options (&opts);
454 if (opts.objectprint)
456 if (((TYPE_CODE (type) == TYPE_CODE_PTR) || TYPE_IS_REFERENCE (type))
457 && (TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_STRUCT))
458 real_type = value_rtti_indirect_type (val, &full, &top, &using_enc);
459 else if (TYPE_CODE (type) == TYPE_CODE_STRUCT)
460 real_type = value_rtti_type (val, &full, &top, &using_enc);
463 printf_filtered ("type = ");
466 create_global_typedef_table (&flags);
470 printf_filtered ("/* real type = ");
471 type_print (real_type, "", gdb_stdout, -1);
473 printf_filtered (" (incomplete object)");
474 printf_filtered (" */\n");
477 LA_PRINT_TYPE (type, "", gdb_stdout, show, 0, &flags);
478 printf_filtered ("\n");
480 do_cleanups (old_chain);
484 whatis_command (char *exp, int from_tty)
486 /* Most of the time users do not want to see all the fields
487 in a structure. If they do they can use the "ptype" command.
488 Hence the "-1" below. */
489 whatis_exp (exp, -1);
492 /* TYPENAME is either the name of a type, or an expression. */
495 ptype_command (char *type_name, int from_tty)
497 whatis_exp (type_name, 1);
500 /* Print integral scalar data VAL, of type TYPE, onto stdio stream STREAM.
501 Used to print data from type structures in a specified type. For example,
502 array bounds may be characters or booleans in some languages, and this
503 allows the ranges to be printed in their "natural" form rather than as
504 decimal integer values.
506 FIXME: This is here simply because only the type printing routines
507 currently use it, and it wasn't clear if it really belonged somewhere
508 else (like printcmd.c). There are a lot of other gdb routines that do
509 something similar, but they are generally concerned with printing values
510 that come from the inferior in target byte order and target size. */
513 print_type_scalar (struct type *type, LONGEST val, struct ui_file *stream)
518 type = check_typedef (type);
520 switch (TYPE_CODE (type))
524 len = TYPE_NFIELDS (type);
525 for (i = 0; i < len; i++)
527 if (TYPE_FIELD_ENUMVAL (type, i) == val)
534 fputs_filtered (TYPE_FIELD_NAME (type, i), stream);
538 print_longest (stream, 'd', 0, val);
543 print_longest (stream, TYPE_UNSIGNED (type) ? 'u' : 'd', 0, val);
547 LA_PRINT_CHAR ((unsigned char) val, type, stream);
551 fprintf_filtered (stream, val ? "TRUE" : "FALSE");
554 case TYPE_CODE_RANGE:
555 print_type_scalar (TYPE_TARGET_TYPE (type), val, stream);
558 case TYPE_CODE_UNDEF:
560 case TYPE_CODE_ARRAY:
561 case TYPE_CODE_STRUCT:
562 case TYPE_CODE_UNION:
567 case TYPE_CODE_STRING:
568 case TYPE_CODE_ERROR:
569 case TYPE_CODE_MEMBERPTR:
570 case TYPE_CODE_METHODPTR:
571 case TYPE_CODE_METHOD:
573 case TYPE_CODE_RVALUE_REF:
574 case TYPE_CODE_NAMESPACE:
575 error (_("internal error: unhandled type in print_type_scalar"));
579 error (_("Invalid type code in symbol table."));
584 /* Dump details of a type specified either directly or indirectly.
585 Uses the same sort of type lookup mechanism as ptype_command()
586 and whatis_command(). */
589 maintenance_print_type (char *type_name, int from_tty)
594 if (type_name != NULL)
596 expression_up expr = parse_expression (type_name);
597 if (expr->elts[0].opcode == OP_TYPE)
599 /* The user expression names a type directly, just use that type. */
600 type = expr->elts[1].type;
604 /* The user expression may name a type indirectly by naming an
605 object of that type. Find that indirectly named type. */
606 val = evaluate_type (expr.get ());
607 type = value_type (val);
611 recursive_dump_type (type, 0);
617 struct cmd_list_element *setprinttypelist;
619 struct cmd_list_element *showprinttypelist;
622 set_print_type (char *arg, int from_tty)
625 "\"set print type\" must be followed by the name of a subcommand.\n");
626 help_list (setprintlist, "set print type ", all_commands, gdb_stdout);
630 show_print_type (char *args, int from_tty)
632 cmd_show_list (showprinttypelist, from_tty, "");
635 static int print_methods = 1;
638 set_print_type_methods (char *args, int from_tty, struct cmd_list_element *c)
640 default_ptype_flags.print_methods = print_methods;
644 show_print_type_methods (struct ui_file *file, int from_tty,
645 struct cmd_list_element *c, const char *value)
647 fprintf_filtered (file, _("Printing of methods defined in a class in %s\n"),
651 static int print_typedefs = 1;
654 set_print_type_typedefs (char *args, int from_tty, struct cmd_list_element *c)
656 default_ptype_flags.print_typedefs = print_typedefs;
660 show_print_type_typedefs (struct ui_file *file, int from_tty,
661 struct cmd_list_element *c, const char *value)
663 fprintf_filtered (file, _("Printing of typedefs defined in a class in %s\n"),
668 _initialize_typeprint (void)
670 struct cmd_list_element *c;
672 c = add_com ("ptype", class_vars, ptype_command, _("\
673 Print definition of type TYPE.\n\
674 Usage: ptype[/FLAGS] TYPE | EXPRESSION\n\
675 Argument may be any type (for example a type name defined by typedef,\n\
676 or \"struct STRUCT-TAG\" or \"class CLASS-NAME\" or \"union UNION-TAG\"\n\
677 or \"enum ENUM-TAG\") or an expression.\n\
678 The selected stack frame's lexical context is used to look up the name.\n\
679 Contrary to \"whatis\", \"ptype\" always unrolls any typedefs.\n\
681 Available FLAGS are:\n\
682 /r print in \"raw\" form; do not substitute typedefs\n\
683 /m do not print methods defined in a class\n\
684 /M print methods defined in a class\n\
685 /t do not print typedefs defined in a class\n\
686 /T print typedefs defined in a class"));
687 set_cmd_completer (c, expression_completer);
689 c = add_com ("whatis", class_vars, whatis_command,
690 _("Print data type of expression EXP.\n\
691 Only one level of typedefs is unrolled. See also \"ptype\"."));
692 set_cmd_completer (c, expression_completer);
694 add_prefix_cmd ("type", no_class, show_print_type,
695 _("Generic command for showing type-printing settings."),
696 &showprinttypelist, "show print type ", 0, &showprintlist);
697 add_prefix_cmd ("type", no_class, set_print_type,
698 _("Generic command for setting how types print."),
699 &setprinttypelist, "show print type ", 0, &setprintlist);
701 add_setshow_boolean_cmd ("methods", no_class, &print_methods,
703 Set printing of methods defined in classes."), _("\
704 Show printing of methods defined in classes."), NULL,
705 set_print_type_methods,
706 show_print_type_methods,
707 &setprinttypelist, &showprinttypelist);
708 add_setshow_boolean_cmd ("typedefs", no_class, &print_typedefs,
710 Set printing of typedefs defined in classes."), _("\
711 Show printing of typedefs defined in classes."), NULL,
712 set_print_type_typedefs,
713 show_print_type_typedefs,
714 &setprinttypelist, &showprinttypelist);
717 /* Print <not allocated> status to stream STREAM. */
720 val_print_not_allocated (struct ui_file *stream)
722 fprintf_filtered (stream, _("<not allocated>"));
725 /* Print <not associated> status to stream STREAM. */
728 val_print_not_associated (struct ui_file *stream)
730 fprintf_filtered (stream, _("<not associated>"));