1 /* Support for printing C values for GDB, the GNU debugger. 2 3 Copyright 1986, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 4 1997, 1998, 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_string.h" 25 #include "symtab.h" 26 #include "gdbtypes.h" 27 #include "expression.h" 28 #include "value.h" 29 #include "valprint.h" 30 #include "language.h" 31 #include "c-lang.h" 32 #include "cp-abi.h" 33 #include "target.h" 34 35 36 /* Print function pointer with inferior address ADDRESS onto stdio 37 stream STREAM. */ 38 39 static void 40 print_function_pointer_address (CORE_ADDR address, struct ui_file *stream) 41 { 42 CORE_ADDR func_addr = gdbarch_convert_from_func_ptr_addr (current_gdbarch, 43 address, 44 ¤t_target); 45 46 /* If the function pointer is represented by a description, print the 47 address of the description. */ 48 if (addressprint && func_addr != address) 49 { 50 fputs_filtered ("@", stream); 51 print_address_numeric (address, 1, stream); 52 fputs_filtered (": ", stream); 53 } 54 print_address_demangle (func_addr, stream, demangle); 55 } 56 57 58 /* Print data of type TYPE located at VALADDR (within GDB), which came from 59 the inferior at address ADDRESS, onto stdio stream STREAM according to 60 FORMAT (a letter or 0 for natural format). The data at VALADDR is in 61 target byte order. 62 63 If the data are a string pointer, returns the number of string characters 64 printed. 65 66 If DEREF_REF is nonzero, then dereference references, otherwise just print 67 them like pointers. 68 69 The PRETTY parameter controls prettyprinting. */ 70 71 int 72 c_val_print (struct type *type, char *valaddr, int embedded_offset, 73 CORE_ADDR address, struct ui_file *stream, int format, 74 int deref_ref, int recurse, enum val_prettyprint pretty) 75 { 76 unsigned int i = 0; /* Number of characters printed */ 77 unsigned len; 78 struct type *elttype; 79 unsigned eltlen; 80 LONGEST val; 81 CORE_ADDR addr; 82 83 CHECK_TYPEDEF (type); 84 switch (TYPE_CODE (type)) 85 { 86 case TYPE_CODE_ARRAY: 87 elttype = check_typedef (TYPE_TARGET_TYPE (type)); 88 if (TYPE_LENGTH (type) > 0 && TYPE_LENGTH (TYPE_TARGET_TYPE (type)) > 0) 89 { 90 eltlen = TYPE_LENGTH (elttype); 91 len = TYPE_LENGTH (type) / eltlen; 92 if (prettyprint_arrays) 93 { 94 print_spaces_filtered (2 + 2 * recurse, stream); 95 } 96 /* For an array of chars, print with string syntax. */ 97 if (eltlen == 1 && 98 ((TYPE_CODE (elttype) == TYPE_CODE_INT) 99 || ((current_language->la_language == language_m2) 100 && (TYPE_CODE (elttype) == TYPE_CODE_CHAR))) 101 && (format == 0 || format == 's')) 102 { 103 /* If requested, look for the first null char and only print 104 elements up to it. */ 105 if (stop_print_at_null) 106 { 107 unsigned int temp_len; 108 109 /* Look for a NULL char. */ 110 for (temp_len = 0; 111 (valaddr + embedded_offset)[temp_len] 112 && temp_len < len && temp_len < print_max; 113 temp_len++); 114 len = temp_len; 115 } 116 117 LA_PRINT_STRING (stream, valaddr + embedded_offset, len, eltlen, 0); 118 i = len; 119 } 120 else 121 { 122 fprintf_filtered (stream, "{"); 123 /* If this is a virtual function table, print the 0th 124 entry specially, and the rest of the members normally. */ 125 if (cp_is_vtbl_ptr_type (elttype)) 126 { 127 i = 1; 128 fprintf_filtered (stream, "%d vtable entries", len - 1); 129 } 130 else 131 { 132 i = 0; 133 } 134 val_print_array_elements (type, valaddr + embedded_offset, address, stream, 135 format, deref_ref, recurse, pretty, i); 136 fprintf_filtered (stream, "}"); 137 } 138 break; 139 } 140 /* Array of unspecified length: treat like pointer to first elt. */ 141 addr = address; 142 goto print_unpacked_pointer; 143 144 case TYPE_CODE_PTR: 145 if (format && format != 's') 146 { 147 print_scalar_formatted (valaddr + embedded_offset, type, format, 0, stream); 148 break; 149 } 150 if (vtblprint && cp_is_vtbl_ptr_type (type)) 151 { 152 /* Print the unmangled name if desired. */ 153 /* Print vtable entry - we only get here if we ARE using 154 -fvtable_thunks. (Otherwise, look under TYPE_CODE_STRUCT.) */ 155 CORE_ADDR addr 156 = extract_typed_address (valaddr + embedded_offset, type); 157 print_function_pointer_address (addr, stream); 158 break; 159 } 160 elttype = check_typedef (TYPE_TARGET_TYPE (type)); 161 if (TYPE_CODE (elttype) == TYPE_CODE_METHOD) 162 { 163 cp_print_class_method (valaddr + embedded_offset, type, stream); 164 } 165 else if (TYPE_CODE (elttype) == TYPE_CODE_MEMBER) 166 { 167 cp_print_class_member (valaddr + embedded_offset, 168 TYPE_DOMAIN_TYPE (TYPE_TARGET_TYPE (type)), 169 stream, "&"); 170 } 171 else 172 { 173 addr = unpack_pointer (type, valaddr + embedded_offset); 174 print_unpacked_pointer: 175 176 if (TYPE_CODE (elttype) == TYPE_CODE_FUNC) 177 { 178 /* Try to print what function it points to. */ 179 print_function_pointer_address (addr, stream); 180 /* Return value is irrelevant except for string pointers. */ 181 return (0); 182 } 183 184 if (addressprint && format != 's') 185 { 186 print_address_numeric (addr, 1, stream); 187 } 188 189 /* For a pointer to char or unsigned char, also print the string 190 pointed to, unless pointer is null. */ 191 /* FIXME: need to handle wchar_t here... */ 192 193 if (TYPE_LENGTH (elttype) == 1 194 && TYPE_CODE (elttype) == TYPE_CODE_INT 195 && (format == 0 || format == 's') 196 && addr != 0) 197 { 198 i = val_print_string (addr, -1, TYPE_LENGTH (elttype), stream); 199 } 200 else if (cp_is_vtbl_member (type)) 201 { 202 /* print vtbl's nicely */ 203 CORE_ADDR vt_address = unpack_pointer (type, valaddr + embedded_offset); 204 205 struct minimal_symbol *msymbol = 206 lookup_minimal_symbol_by_pc (vt_address); 207 if ((msymbol != NULL) && 208 (vt_address == SYMBOL_VALUE_ADDRESS (msymbol))) 209 { 210 fputs_filtered (" <", stream); 211 fputs_filtered (SYMBOL_PRINT_NAME (msymbol), stream); 212 fputs_filtered (">", stream); 213 } 214 if (vt_address && vtblprint) 215 { 216 struct value *vt_val; 217 struct symbol *wsym = (struct symbol *) NULL; 218 struct type *wtype; 219 struct block *block = (struct block *) NULL; 220 int is_this_fld; 221 222 if (msymbol != NULL) 223 wsym = lookup_symbol (DEPRECATED_SYMBOL_NAME (msymbol), block, 224 VAR_DOMAIN, &is_this_fld, NULL); 225 226 if (wsym) 227 { 228 wtype = SYMBOL_TYPE (wsym); 229 } 230 else 231 { 232 wtype = TYPE_TARGET_TYPE (type); 233 } 234 vt_val = value_at (wtype, vt_address, NULL); 235 val_print (VALUE_TYPE (vt_val), VALUE_CONTENTS (vt_val), 0, 236 VALUE_ADDRESS (vt_val), stream, format, 237 deref_ref, recurse + 1, pretty); 238 if (pretty) 239 { 240 fprintf_filtered (stream, "\n"); 241 print_spaces_filtered (2 + 2 * recurse, stream); 242 } 243 } 244 } 245 246 /* Return number of characters printed, including the terminating 247 '\0' if we reached the end. val_print_string takes care including 248 the terminating '\0' if necessary. */ 249 return i; 250 } 251 break; 252 253 case TYPE_CODE_MEMBER: 254 error ("not implemented: member type in c_val_print"); 255 break; 256 257 case TYPE_CODE_REF: 258 elttype = check_typedef (TYPE_TARGET_TYPE (type)); 259 if (TYPE_CODE (elttype) == TYPE_CODE_MEMBER) 260 { 261 cp_print_class_member (valaddr + embedded_offset, 262 TYPE_DOMAIN_TYPE (elttype), 263 stream, ""); 264 break; 265 } 266 if (addressprint) 267 { 268 CORE_ADDR addr 269 = extract_typed_address (valaddr + embedded_offset, type); 270 fprintf_filtered (stream, "@"); 271 print_address_numeric (addr, 1, stream); 272 if (deref_ref) 273 fputs_filtered (": ", stream); 274 } 275 /* De-reference the reference. */ 276 if (deref_ref) 277 { 278 if (TYPE_CODE (elttype) != TYPE_CODE_UNDEF) 279 { 280 struct value *deref_val = 281 value_at 282 (TYPE_TARGET_TYPE (type), 283 unpack_pointer (lookup_pointer_type (builtin_type_void), 284 valaddr + embedded_offset), 285 NULL); 286 val_print (VALUE_TYPE (deref_val), 287 VALUE_CONTENTS (deref_val), 288 0, 289 VALUE_ADDRESS (deref_val), 290 stream, 291 format, 292 deref_ref, 293 recurse, 294 pretty); 295 } 296 else 297 fputs_filtered ("???", stream); 298 } 299 break; 300 301 case TYPE_CODE_UNION: 302 if (recurse && !unionprint) 303 { 304 fprintf_filtered (stream, "{...}"); 305 break; 306 } 307 /* Fall through. */ 308 case TYPE_CODE_STRUCT: 309 /*FIXME: Abstract this away */ 310 if (vtblprint && cp_is_vtbl_ptr_type (type)) 311 { 312 /* Print the unmangled name if desired. */ 313 /* Print vtable entry - we only get here if NOT using 314 -fvtable_thunks. (Otherwise, look under TYPE_CODE_PTR.) */ 315 int offset = (embedded_offset + 316 TYPE_FIELD_BITPOS (type, VTBL_FNADDR_OFFSET) / 8); 317 struct type *field_type = TYPE_FIELD_TYPE (type, VTBL_FNADDR_OFFSET); 318 CORE_ADDR addr 319 = extract_typed_address (valaddr + offset, field_type); 320 321 print_function_pointer_address (addr, stream); 322 } 323 else 324 cp_print_value_fields (type, type, valaddr, embedded_offset, address, stream, format, 325 recurse, pretty, NULL, 0); 326 break; 327 328 case TYPE_CODE_ENUM: 329 if (format) 330 { 331 print_scalar_formatted (valaddr + embedded_offset, type, format, 0, stream); 332 break; 333 } 334 len = TYPE_NFIELDS (type); 335 val = unpack_long (type, valaddr + embedded_offset); 336 for (i = 0; i < len; i++) 337 { 338 QUIT; 339 if (val == TYPE_FIELD_BITPOS (type, i)) 340 { 341 break; 342 } 343 } 344 if (i < len) 345 { 346 fputs_filtered (TYPE_FIELD_NAME (type, i), stream); 347 } 348 else 349 { 350 print_longest (stream, 'd', 0, val); 351 } 352 break; 353 354 case TYPE_CODE_FUNC: 355 if (format) 356 { 357 print_scalar_formatted (valaddr + embedded_offset, type, format, 0, stream); 358 break; 359 } 360 /* FIXME, we should consider, at least for ANSI C language, eliminating 361 the distinction made between FUNCs and POINTERs to FUNCs. */ 362 fprintf_filtered (stream, "{"); 363 type_print (type, "", stream, -1); 364 fprintf_filtered (stream, "} "); 365 /* Try to print what function it points to, and its address. */ 366 print_address_demangle (address, stream, demangle); 367 break; 368 369 case TYPE_CODE_BOOL: 370 format = format ? format : output_format; 371 if (format) 372 print_scalar_formatted (valaddr + embedded_offset, type, format, 0, stream); 373 else 374 { 375 val = unpack_long (type, valaddr + embedded_offset); 376 if (val == 0) 377 fputs_filtered ("false", stream); 378 else if (val == 1) 379 fputs_filtered ("true", stream); 380 else 381 print_longest (stream, 'd', 0, val); 382 } 383 break; 384 385 case TYPE_CODE_RANGE: 386 /* FIXME: create_range_type does not set the unsigned bit in a 387 range type (I think it probably should copy it from the target 388 type), so we won't print values which are too large to 389 fit in a signed integer correctly. */ 390 /* FIXME: Doesn't handle ranges of enums correctly. (Can't just 391 print with the target type, though, because the size of our type 392 and the target type might differ). */ 393 /* FALLTHROUGH */ 394 395 case TYPE_CODE_INT: 396 format = format ? format : output_format; 397 if (format) 398 { 399 print_scalar_formatted (valaddr + embedded_offset, type, format, 0, stream); 400 } 401 else 402 { 403 val_print_type_code_int (type, valaddr + embedded_offset, stream); 404 /* C and C++ has no single byte int type, char is used instead. 405 Since we don't know whether the value is really intended to 406 be used as an integer or a character, print the character 407 equivalent as well. */ 408 if (TYPE_LENGTH (type) == 1) 409 { 410 fputs_filtered (" ", stream); 411 LA_PRINT_CHAR ((unsigned char) unpack_long (type, valaddr + embedded_offset), 412 stream); 413 } 414 } 415 break; 416 417 case TYPE_CODE_CHAR: 418 format = format ? format : output_format; 419 if (format) 420 { 421 print_scalar_formatted (valaddr + embedded_offset, type, format, 0, stream); 422 } 423 else 424 { 425 val = unpack_long (type, valaddr + embedded_offset); 426 if (TYPE_UNSIGNED (type)) 427 fprintf_filtered (stream, "%u", (unsigned int) val); 428 else 429 fprintf_filtered (stream, "%d", (int) val); 430 fputs_filtered (" ", stream); 431 LA_PRINT_CHAR ((unsigned char) val, stream); 432 } 433 break; 434 435 case TYPE_CODE_FLT: 436 if (format) 437 { 438 print_scalar_formatted (valaddr + embedded_offset, type, format, 0, stream); 439 } 440 else 441 { 442 print_floating (valaddr + embedded_offset, type, stream); 443 } 444 break; 445 446 case TYPE_CODE_METHOD: 447 { 448 struct value *v = value_at (type, address, NULL); 449 cp_print_class_method (VALUE_CONTENTS (value_addr (v)), 450 lookup_pointer_type (type), stream); 451 break; 452 } 453 454 case TYPE_CODE_VOID: 455 fprintf_filtered (stream, "void"); 456 break; 457 458 case TYPE_CODE_ERROR: 459 fprintf_filtered (stream, "<error type>"); 460 break; 461 462 case TYPE_CODE_UNDEF: 463 /* This happens (without TYPE_FLAG_STUB set) on systems which don't use 464 dbx xrefs (NO_DBX_XREFS in gcc) if a file has a "struct foo *bar" 465 and no complete type for struct foo in that file. */ 466 fprintf_filtered (stream, "<incomplete type>"); 467 break; 468 469 case TYPE_CODE_COMPLEX: 470 if (format) 471 print_scalar_formatted (valaddr + embedded_offset, 472 TYPE_TARGET_TYPE (type), 473 format, 0, stream); 474 else 475 print_floating (valaddr + embedded_offset, TYPE_TARGET_TYPE (type), 476 stream); 477 fprintf_filtered (stream, " + "); 478 if (format) 479 print_scalar_formatted (valaddr + embedded_offset 480 + TYPE_LENGTH (TYPE_TARGET_TYPE (type)), 481 TYPE_TARGET_TYPE (type), 482 format, 0, stream); 483 else 484 print_floating (valaddr + embedded_offset 485 + TYPE_LENGTH (TYPE_TARGET_TYPE (type)), 486 TYPE_TARGET_TYPE (type), 487 stream); 488 fprintf_filtered (stream, " * I"); 489 break; 490 491 default: 492 error ("Invalid C/C++ type code %d in symbol table.", TYPE_CODE (type)); 493 } 494 gdb_flush (stream); 495 return (0); 496 } 497 498 int 499 c_value_print (struct value *val, struct ui_file *stream, int format, 500 enum val_prettyprint pretty) 501 { 502 struct type *type = VALUE_TYPE (val); 503 struct type *real_type; 504 int full, top, using_enc; 505 506 /* If it is a pointer, indicate what it points to. 507 508 Print type also if it is a reference. 509 510 C++: if it is a member pointer, we will take care 511 of that when we print it. */ 512 if (TYPE_CODE (type) == TYPE_CODE_PTR || 513 TYPE_CODE (type) == TYPE_CODE_REF) 514 { 515 /* Hack: remove (char *) for char strings. Their 516 type is indicated by the quoted string anyway. */ 517 if (TYPE_CODE (type) == TYPE_CODE_PTR && 518 TYPE_NAME (type) == NULL && 519 TYPE_NAME (TYPE_TARGET_TYPE (type)) != NULL && 520 strcmp (TYPE_NAME (TYPE_TARGET_TYPE (type)), "char") == 0) 521 { 522 /* Print nothing */ 523 } 524 else if (objectprint && (TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_CLASS)) 525 { 526 527 if (TYPE_CODE(type) == TYPE_CODE_REF) 528 { 529 /* Copy value, change to pointer, so we don't get an 530 * error about a non-pointer type in value_rtti_target_type 531 */ 532 struct value *temparg; 533 temparg=value_copy(val); 534 VALUE_TYPE (temparg) = lookup_pointer_type(TYPE_TARGET_TYPE(type)); 535 val=temparg; 536 } 537 /* Pointer to class, check real type of object */ 538 fprintf_filtered (stream, "("); 539 real_type = value_rtti_target_type (val, &full, &top, &using_enc); 540 if (real_type) 541 { 542 /* RTTI entry found */ 543 if (TYPE_CODE (type) == TYPE_CODE_PTR) 544 { 545 /* create a pointer type pointing to the real type */ 546 type = lookup_pointer_type (real_type); 547 } 548 else 549 { 550 /* create a reference type referencing the real type */ 551 type = lookup_reference_type (real_type); 552 } 553 /* JYG: Need to adjust pointer value. */ 554 val->aligner.contents[0] -= top; 555 556 /* Note: When we look up RTTI entries, we don't get any 557 information on const or volatile attributes */ 558 } 559 type_print (type, "", stream, -1); 560 fprintf_filtered (stream, ") "); 561 } 562 else 563 { 564 /* normal case */ 565 fprintf_filtered (stream, "("); 566 type_print (type, "", stream, -1); 567 fprintf_filtered (stream, ") "); 568 } 569 } 570 if (objectprint && (TYPE_CODE (VALUE_TYPE (val)) == TYPE_CODE_CLASS)) 571 { 572 /* Attempt to determine real type of object */ 573 real_type = value_rtti_type (val, &full, &top, &using_enc); 574 if (real_type) 575 { 576 /* We have RTTI information, so use it */ 577 val = value_full_object (val, real_type, full, top, using_enc); 578 fprintf_filtered (stream, "(%s%s) ", 579 TYPE_NAME (real_type), 580 full ? "" : " [incomplete object]"); 581 /* Print out object: enclosing type is same as real_type if full */ 582 return val_print (VALUE_ENCLOSING_TYPE (val), VALUE_CONTENTS_ALL (val), 0, 583 VALUE_ADDRESS (val), stream, format, 1, 0, pretty); 584 /* Note: When we look up RTTI entries, we don't get any information on 585 const or volatile attributes */ 586 } 587 else if (type != VALUE_ENCLOSING_TYPE (val)) 588 { 589 /* No RTTI information, so let's do our best */ 590 fprintf_filtered (stream, "(%s ?) ", 591 TYPE_NAME (VALUE_ENCLOSING_TYPE (val))); 592 return val_print (VALUE_ENCLOSING_TYPE (val), VALUE_CONTENTS_ALL (val), 0, 593 VALUE_ADDRESS (val), stream, format, 1, 0, pretty); 594 } 595 /* Otherwise, we end up at the return outside this "if" */ 596 } 597 598 return val_print (type, VALUE_CONTENTS_ALL (val), 599 VALUE_EMBEDDED_OFFSET (val), 600 VALUE_ADDRESS (val) + VALUE_OFFSET (val), 601 stream, format, 1, 0, pretty); 602 } 603