1 /* Language independent support for printing types for GDB, the GNU debugger.
2
3 Copyright 1986, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1998,
4 1999, 2000, 2001, 2003 Free Software Foundation, Inc.
5
6 This file is part of GDB.
7
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 2 of the License, or
11 (at your option) any later version.
12
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.
17
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 59 Temple Place - Suite 330,
21 Boston, MA 02111-1307, USA. */
22
23 #include "defs.h"
24 #include "gdb_obstack.h"
25 #include "bfd.h" /* Binary File Description */
26 #include "symtab.h"
27 #include "gdbtypes.h"
28 #include "expression.h"
29 #include "value.h"
30 #include "gdbcore.h"
31 #include "command.h"
32 #include "gdbcmd.h"
33 #include "target.h"
34 #include "language.h"
35 #include "cp-abi.h"
36 #include "typeprint.h"
37 #include "gdb_string.h"
38 #include <errno.h>
39
40 /* For real-type printing in whatis_exp() */
41 extern int objectprint; /* Controls looking up an object's derived type
42 using what we find in its vtables. */
43
44 extern void _initialize_typeprint (void);
45
46 static void ptype_command (char *, int);
47
48 static struct type *ptype_eval (struct expression *);
49
50 static void whatis_command (char *, int);
51
52 static void whatis_exp (char *, int);
53
54 /* Print a description of a type in the format of a
55 typedef for the current language.
56 NEW is the new name for a type TYPE. */
57
58 void
typedef_print(struct type * type,struct symbol * new,struct ui_file * stream)59 typedef_print (struct type *type, struct symbol *new, struct ui_file *stream)
60 {
61 CHECK_TYPEDEF (type);
62 switch (current_language->la_language)
63 {
64 #ifdef _LANG_c
65 case language_c:
66 case language_cplus:
67 fprintf_filtered (stream, "typedef ");
68 type_print (type, "", stream, 0);
69 if (TYPE_NAME ((SYMBOL_TYPE (new))) == 0
70 || strcmp (TYPE_NAME ((SYMBOL_TYPE (new))), DEPRECATED_SYMBOL_NAME (new)) != 0)
71 fprintf_filtered (stream, " %s", SYMBOL_PRINT_NAME (new));
72 break;
73 #endif
74 #ifdef _LANG_m2
75 case language_m2:
76 fprintf_filtered (stream, "TYPE ");
77 if (!TYPE_NAME (SYMBOL_TYPE (new))
78 || strcmp (TYPE_NAME ((SYMBOL_TYPE (new))), DEPRECATED_SYMBOL_NAME (new)) != 0)
79 fprintf_filtered (stream, "%s = ", SYMBOL_PRINT_NAME (new));
80 else
81 fprintf_filtered (stream, "<builtin> = ");
82 type_print (type, "", stream, 0);
83 break;
84 #endif
85 #ifdef _LANG_pascal
86 case language_pascal:
87 fprintf_filtered (stream, "type ");
88 fprintf_filtered (stream, "%s = ", SYMBOL_PRINT_NAME (new));
89 type_print (type, "", stream, 0);
90 break;
91 #endif
92 default:
93 error ("Language not supported.");
94 }
95 fprintf_filtered (stream, ";\n");
96 }
97
98 /* Print a description of a type TYPE in the form of a declaration of a
99 variable named VARSTRING. (VARSTRING is demangled if necessary.)
100 Output goes to STREAM (via stdio).
101 If SHOW is positive, we show the contents of the outermost level
102 of structure even if there is a type name that could be used instead.
103 If SHOW is negative, we never show the details of elements' types. */
104
105 void
type_print(struct type * type,char * varstring,struct ui_file * stream,int show)106 type_print (struct type *type, char *varstring, struct ui_file *stream,
107 int show)
108 {
109 LA_PRINT_TYPE (type, varstring, stream, show, 0);
110 }
111
112 /* Print type of EXP, or last thing in value history if EXP == NULL.
113 show is passed to type_print. */
114
115 static void
whatis_exp(char * exp,int show)116 whatis_exp (char *exp, int show)
117 {
118 struct expression *expr;
119 struct value *val;
120 struct cleanup *old_chain = NULL;
121 struct type *real_type = NULL;
122 struct type *type;
123 int full = 0;
124 int top = -1;
125 int using_enc = 0;
126
127 if (exp)
128 {
129 expr = parse_expression (exp);
130 old_chain = make_cleanup (free_current_contents, &expr);
131 val = evaluate_type (expr);
132 }
133 else
134 val = access_value_history (0);
135
136 type = VALUE_TYPE (val);
137
138 if (objectprint)
139 {
140 if (((TYPE_CODE (type) == TYPE_CODE_PTR) ||
141 (TYPE_CODE (type) == TYPE_CODE_REF))
142 &&
143 (TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_CLASS))
144 {
145 real_type = value_rtti_target_type (val, &full, &top, &using_enc);
146 if (real_type)
147 {
148 if (TYPE_CODE (type) == TYPE_CODE_PTR)
149 real_type = lookup_pointer_type (real_type);
150 else
151 real_type = lookup_reference_type (real_type);
152 }
153 }
154 else if (TYPE_CODE (type) == TYPE_CODE_CLASS)
155 real_type = value_rtti_type (val, &full, &top, &using_enc);
156 }
157
158 printf_filtered ("type = ");
159
160 if (real_type)
161 {
162 printf_filtered ("/* real type = ");
163 type_print (real_type, "", gdb_stdout, -1);
164 if (! full)
165 printf_filtered (" (incomplete object)");
166 printf_filtered (" */\n");
167 }
168
169 type_print (type, "", gdb_stdout, show);
170 printf_filtered ("\n");
171
172 if (exp)
173 do_cleanups (old_chain);
174 }
175
176 static void
whatis_command(char * exp,int from_tty)177 whatis_command (char *exp, int from_tty)
178 {
179 /* Most of the time users do not want to see all the fields
180 in a structure. If they do they can use the "ptype" command.
181 Hence the "-1" below. */
182 whatis_exp (exp, -1);
183 }
184
185 /* Simple subroutine for ptype_command. */
186
187 static struct type *
ptype_eval(struct expression * exp)188 ptype_eval (struct expression *exp)
189 {
190 if (exp->elts[0].opcode == OP_TYPE)
191 {
192 return (exp->elts[1].type);
193 }
194 else
195 {
196 return (NULL);
197 }
198 }
199
200 /* TYPENAME is either the name of a type, or an expression. */
201
202 static void
ptype_command(char * typename,int from_tty)203 ptype_command (char *typename, int from_tty)
204 {
205 struct type *type;
206 struct expression *expr;
207 struct cleanup *old_chain;
208
209 if (typename == NULL)
210 {
211 /* Print type of last thing in value history. */
212 whatis_exp (typename, 1);
213 }
214 else
215 {
216 expr = parse_expression (typename);
217 old_chain = make_cleanup (free_current_contents, &expr);
218 type = ptype_eval (expr);
219 if (type != NULL)
220 {
221 /* User did "ptype <typename>" */
222 printf_filtered ("type = ");
223 type_print (type, "", gdb_stdout, 1);
224 printf_filtered ("\n");
225 do_cleanups (old_chain);
226 }
227 else
228 {
229 /* User did "ptype <symbolname>" */
230 do_cleanups (old_chain);
231 whatis_exp (typename, 1);
232 }
233 }
234 }
235
236 /* Print integral scalar data VAL, of type TYPE, onto stdio stream STREAM.
237 Used to print data from type structures in a specified type. For example,
238 array bounds may be characters or booleans in some languages, and this
239 allows the ranges to be printed in their "natural" form rather than as
240 decimal integer values.
241
242 FIXME: This is here simply because only the type printing routines
243 currently use it, and it wasn't clear if it really belonged somewhere
244 else (like printcmd.c). There are a lot of other gdb routines that do
245 something similar, but they are generally concerned with printing values
246 that come from the inferior in target byte order and target size. */
247
248 void
print_type_scalar(struct type * type,LONGEST val,struct ui_file * stream)249 print_type_scalar (struct type *type, LONGEST val, struct ui_file *stream)
250 {
251 unsigned int i;
252 unsigned len;
253
254 CHECK_TYPEDEF (type);
255
256 switch (TYPE_CODE (type))
257 {
258
259 case TYPE_CODE_ENUM:
260 len = TYPE_NFIELDS (type);
261 for (i = 0; i < len; i++)
262 {
263 if (TYPE_FIELD_BITPOS (type, i) == val)
264 {
265 break;
266 }
267 }
268 if (i < len)
269 {
270 fputs_filtered (TYPE_FIELD_NAME (type, i), stream);
271 }
272 else
273 {
274 print_longest (stream, 'd', 0, val);
275 }
276 break;
277
278 case TYPE_CODE_INT:
279 print_longest (stream, TYPE_UNSIGNED (type) ? 'u' : 'd', 0, val);
280 break;
281
282 case TYPE_CODE_CHAR:
283 LA_PRINT_CHAR ((unsigned char) val, stream);
284 break;
285
286 case TYPE_CODE_BOOL:
287 fprintf_filtered (stream, val ? "TRUE" : "FALSE");
288 break;
289
290 case TYPE_CODE_RANGE:
291 print_type_scalar (TYPE_TARGET_TYPE (type), val, stream);
292 return;
293
294 case TYPE_CODE_UNDEF:
295 case TYPE_CODE_PTR:
296 case TYPE_CODE_ARRAY:
297 case TYPE_CODE_STRUCT:
298 case TYPE_CODE_UNION:
299 case TYPE_CODE_FUNC:
300 case TYPE_CODE_FLT:
301 case TYPE_CODE_VOID:
302 case TYPE_CODE_SET:
303 case TYPE_CODE_STRING:
304 case TYPE_CODE_ERROR:
305 case TYPE_CODE_MEMBER:
306 case TYPE_CODE_METHOD:
307 case TYPE_CODE_REF:
308 case TYPE_CODE_NAMESPACE:
309 error ("internal error: unhandled type in print_type_scalar");
310 break;
311
312 default:
313 error ("Invalid type code in symbol table.");
314 }
315 gdb_flush (stream);
316 }
317
318 /* Dump details of a type specified either directly or indirectly.
319 Uses the same sort of type lookup mechanism as ptype_command()
320 and whatis_command(). */
321
322 void
maintenance_print_type(char * typename,int from_tty)323 maintenance_print_type (char *typename, int from_tty)
324 {
325 struct value *val;
326 struct type *type;
327 struct cleanup *old_chain;
328 struct expression *expr;
329
330 if (typename != NULL)
331 {
332 expr = parse_expression (typename);
333 old_chain = make_cleanup (free_current_contents, &expr);
334 if (expr->elts[0].opcode == OP_TYPE)
335 {
336 /* The user expression names a type directly, just use that type. */
337 type = expr->elts[1].type;
338 }
339 else
340 {
341 /* The user expression may name a type indirectly by naming an
342 object of that type. Find that indirectly named type. */
343 val = evaluate_type (expr);
344 type = VALUE_TYPE (val);
345 }
346 if (type != NULL)
347 {
348 recursive_dump_type (type, 0);
349 }
350 do_cleanups (old_chain);
351 }
352 }
353
354
355 void
_initialize_typeprint(void)356 _initialize_typeprint (void)
357 {
358
359 add_com ("ptype", class_vars, ptype_command,
360 "Print definition of type TYPE.\n\
361 Argument may be a type name defined by typedef, or \"struct STRUCT-TAG\"\n\
362 or \"class CLASS-NAME\" or \"union UNION-TAG\" or \"enum ENUM-TAG\".\n\
363 The selected stack frame's lexical context is used to look up the name.");
364
365 add_com ("whatis", class_vars, whatis_command,
366 "Print data type of expression EXP.");
367
368 }
369