1 /* Language independent support for printing types for GDB, the GNU debugger.
3 Copyright (C) 1986-2015 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 = 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 = a;
102 const struct typedef_field *tfb = 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 (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 = 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 = 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);
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 = htab_find (flags->local_typedefs->table, &tf);
329 return find_global_typedef (flags, t);
334 /* Print a description of a type in the format of a
335 typedef for the current language.
336 NEW is the new name for a type TYPE. */
339 typedef_print (struct type *type, struct symbol *newobj, struct ui_file *stream)
341 LA_PRINT_TYPEDEF (type, newobj, stream);
344 /* The default way to print a typedef. */
347 default_print_typedef (struct type *type, struct symbol *new_symbol,
348 struct ui_file *stream)
350 error (_("Language not supported."));
353 /* Print a description of a type TYPE in the form of a declaration of a
354 variable named VARSTRING. (VARSTRING is demangled if necessary.)
355 Output goes to STREAM (via stdio).
356 If SHOW is positive, we show the contents of the outermost level
357 of structure even if there is a type name that could be used instead.
358 If SHOW is negative, we never show the details of elements' types. */
361 type_print (struct type *type, const char *varstring, struct ui_file *stream,
364 LA_PRINT_TYPE (type, varstring, stream, show, 0, &default_ptype_flags);
367 /* Print TYPE to a string, returning it. The caller is responsible for
368 freeing the string. */
371 type_to_string (struct type *type)
375 struct cleanup *old_chain;
377 stb = mem_fileopen ();
378 old_chain = make_cleanup_ui_file_delete (stb);
382 type_print (type, "", stb, -1);
383 s = ui_file_xstrdup (stb, NULL);
385 CATCH (except, RETURN_MASK_ALL)
391 do_cleanups (old_chain);
396 /* Print type of EXP, or last thing in value history if EXP == NULL.
397 show is passed to type_print. */
400 whatis_exp (char *exp, int show)
402 struct expression *expr;
404 struct cleanup *old_chain;
405 struct type *real_type = NULL;
410 struct value_print_options opts;
411 struct type_print_options flags = default_ptype_flags;
413 old_chain = make_cleanup (null_cleanup, NULL);
421 for (++exp; *exp && !isspace (*exp); ++exp)
429 flags.print_methods = 0;
432 flags.print_methods = 1;
435 flags.print_typedefs = 0;
438 flags.print_typedefs = 1;
441 error (_("unrecognized flag '%c'"), *exp);
446 if (!*exp && !seen_one)
447 error (_("flag expected"));
449 error (_("expected space after format"));
450 exp = skip_spaces (exp);
453 expr = parse_expression (exp);
454 make_cleanup (free_current_contents, &expr);
455 val = evaluate_type (expr);
458 val = access_value_history (0);
460 type = value_type (val);
462 get_user_print_options (&opts);
463 if (opts.objectprint)
465 if (((TYPE_CODE (type) == TYPE_CODE_PTR)
466 || (TYPE_CODE (type) == TYPE_CODE_REF))
467 && (TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_STRUCT))
468 real_type = value_rtti_indirect_type (val, &full, &top, &using_enc);
469 else if (TYPE_CODE (type) == TYPE_CODE_STRUCT)
470 real_type = value_rtti_type (val, &full, &top, &using_enc);
473 printf_filtered ("type = ");
476 create_global_typedef_table (&flags);
480 printf_filtered ("/* real type = ");
481 type_print (real_type, "", gdb_stdout, -1);
483 printf_filtered (" (incomplete object)");
484 printf_filtered (" */\n");
487 LA_PRINT_TYPE (type, "", gdb_stdout, show, 0, &flags);
488 printf_filtered ("\n");
490 do_cleanups (old_chain);
494 whatis_command (char *exp, int from_tty)
496 /* Most of the time users do not want to see all the fields
497 in a structure. If they do they can use the "ptype" command.
498 Hence the "-1" below. */
499 whatis_exp (exp, -1);
502 /* TYPENAME is either the name of a type, or an expression. */
505 ptype_command (char *type_name, int from_tty)
507 whatis_exp (type_name, 1);
510 /* Print integral scalar data VAL, of type TYPE, onto stdio stream STREAM.
511 Used to print data from type structures in a specified type. For example,
512 array bounds may be characters or booleans in some languages, and this
513 allows the ranges to be printed in their "natural" form rather than as
514 decimal integer values.
516 FIXME: This is here simply because only the type printing routines
517 currently use it, and it wasn't clear if it really belonged somewhere
518 else (like printcmd.c). There are a lot of other gdb routines that do
519 something similar, but they are generally concerned with printing values
520 that come from the inferior in target byte order and target size. */
523 print_type_scalar (struct type *type, LONGEST val, struct ui_file *stream)
528 type = check_typedef (type);
530 switch (TYPE_CODE (type))
534 len = TYPE_NFIELDS (type);
535 for (i = 0; i < len; i++)
537 if (TYPE_FIELD_ENUMVAL (type, i) == val)
544 fputs_filtered (TYPE_FIELD_NAME (type, i), stream);
548 print_longest (stream, 'd', 0, val);
553 print_longest (stream, TYPE_UNSIGNED (type) ? 'u' : 'd', 0, val);
557 LA_PRINT_CHAR ((unsigned char) val, type, stream);
561 fprintf_filtered (stream, val ? "TRUE" : "FALSE");
564 case TYPE_CODE_RANGE:
565 print_type_scalar (TYPE_TARGET_TYPE (type), val, stream);
568 case TYPE_CODE_UNDEF:
570 case TYPE_CODE_ARRAY:
571 case TYPE_CODE_STRUCT:
572 case TYPE_CODE_UNION:
577 case TYPE_CODE_STRING:
578 case TYPE_CODE_ERROR:
579 case TYPE_CODE_MEMBERPTR:
580 case TYPE_CODE_METHODPTR:
581 case TYPE_CODE_METHOD:
583 case TYPE_CODE_NAMESPACE:
584 error (_("internal error: unhandled type in print_type_scalar"));
588 error (_("Invalid type code in symbol table."));
593 /* Dump details of a type specified either directly or indirectly.
594 Uses the same sort of type lookup mechanism as ptype_command()
595 and whatis_command(). */
598 maintenance_print_type (char *type_name, int from_tty)
602 struct cleanup *old_chain;
603 struct expression *expr;
605 if (type_name != NULL)
607 expr = parse_expression (type_name);
608 old_chain = make_cleanup (free_current_contents, &expr);
609 if (expr->elts[0].opcode == OP_TYPE)
611 /* The user expression names a type directly, just use that type. */
612 type = expr->elts[1].type;
616 /* The user expression may name a type indirectly by naming an
617 object of that type. Find that indirectly named type. */
618 val = evaluate_type (expr);
619 type = value_type (val);
623 recursive_dump_type (type, 0);
625 do_cleanups (old_chain);
630 struct cmd_list_element *setprinttypelist;
632 struct cmd_list_element *showprinttypelist;
635 set_print_type (char *arg, int from_tty)
638 "\"set print type\" must be followed by the name of a subcommand.\n");
639 help_list (setprintlist, "set print type ", all_commands, gdb_stdout);
643 show_print_type (char *args, int from_tty)
645 cmd_show_list (showprinttypelist, from_tty, "");
648 static int print_methods = 1;
651 set_print_type_methods (char *args, int from_tty, struct cmd_list_element *c)
653 default_ptype_flags.print_methods = print_methods;
657 show_print_type_methods (struct ui_file *file, int from_tty,
658 struct cmd_list_element *c, const char *value)
660 fprintf_filtered (file, _("Printing of methods defined in a class in %s\n"),
664 static int print_typedefs = 1;
667 set_print_type_typedefs (char *args, int from_tty, struct cmd_list_element *c)
669 default_ptype_flags.print_typedefs = print_typedefs;
673 show_print_type_typedefs (struct ui_file *file, int from_tty,
674 struct cmd_list_element *c, const char *value)
676 fprintf_filtered (file, _("Printing of typedefs defined in a class in %s\n"),
681 _initialize_typeprint (void)
683 struct cmd_list_element *c;
685 c = add_com ("ptype", class_vars, ptype_command, _("\
686 Print definition of type TYPE.\n\
687 Usage: ptype[/FLAGS] TYPE | EXPRESSION\n\
688 Argument may be any type (for example a type name defined by typedef,\n\
689 or \"struct STRUCT-TAG\" or \"class CLASS-NAME\" or \"union UNION-TAG\"\n\
690 or \"enum ENUM-TAG\") or an expression.\n\
691 The selected stack frame's lexical context is used to look up the name.\n\
692 Contrary to \"whatis\", \"ptype\" always unrolls any typedefs.\n\
694 Available FLAGS are:\n\
695 /r print in \"raw\" form; do not substitute typedefs\n\
696 /m do not print methods defined in a class\n\
697 /M print methods defined in a class\n\
698 /t do not print typedefs defined in a class\n\
699 /T print typedefs defined in a class"));
700 set_cmd_completer (c, expression_completer);
702 c = add_com ("whatis", class_vars, whatis_command,
703 _("Print data type of expression EXP.\n\
704 Only one level of typedefs is unrolled. See also \"ptype\"."));
705 set_cmd_completer (c, expression_completer);
707 add_prefix_cmd ("type", no_class, show_print_type,
708 _("Generic command for showing type-printing settings."),
709 &showprinttypelist, "show print type ", 0, &showprintlist);
710 add_prefix_cmd ("type", no_class, set_print_type,
711 _("Generic command for setting how types print."),
712 &setprinttypelist, "show print type ", 0, &setprintlist);
714 add_setshow_boolean_cmd ("methods", no_class, &print_methods,
716 Set printing of methods defined in classes."), _("\
717 Show printing of methods defined in classes."), NULL,
718 set_print_type_methods,
719 show_print_type_methods,
720 &setprinttypelist, &showprinttypelist);
721 add_setshow_boolean_cmd ("typedefs", no_class, &print_typedefs,
723 Set printing of typedefs defined in classes."), _("\
724 Show printing of typedefs defined in classes."), NULL,
725 set_print_type_typedefs,
726 show_print_type_typedefs,
727 &setprinttypelist, &showprinttypelist);