gdb/jv-valprint.c

   1 /* Support for printing Java values for GDB, the GNU debugger.
   2
   3    Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007,
   4    2008, 2009, 2010, 2011 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 3 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, see <http://www.gnu.org/licenses/>.  */
  20
  21 #include "defs.h"
  22 #include "symtab.h"
  23 #include "gdbtypes.h"
  24 #include "gdbcore.h"
  25 #include "expression.h"
  26 #include "value.h"
  27 #include "demangle.h"
  28 #include "valprint.h"
  29 #include "language.h"
  30 #include "jv-lang.h"
  31 #include "c-lang.h"
  32 #include "annotate.h"
  33 #include "gdb_string.h"
  34
  35 /* Local functions */
  36
  37 int
  38 java_value_print (struct value *val, struct ui_file *stream,
  39                   const struct value_print_options *options)
  40 {
  41   struct gdbarch *gdbarch = get_type_arch (value_type (val));
  42   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
  43   struct type *type;
  44   CORE_ADDR address;
  45   int i;
  46   char *name;
  47   struct value_print_options opts;
  48
  49   type = value_type (val);
  50   address = value_address (val);
  51
  52   if (is_object_type (type))
  53     {
  54       CORE_ADDR obj_addr;
  55
  56       /* Get the run-time type, and cast the object into that.  */
  57
  58       obj_addr = unpack_pointer (type, value_contents (val));
  59
  60       if (obj_addr != 0)
  61         {
  62           type = type_from_class (gdbarch, java_class_from_object (val));
  63           type = lookup_pointer_type (type);
  64
  65           val = value_at (type, address);
  66         }
  67     }
  68
  69   if (TYPE_CODE (type) == TYPE_CODE_PTR && !value_logical_not (val))
  70     type_print (TYPE_TARGET_TYPE (type), "", stream, -1);
  71
  72   name = TYPE_TAG_NAME (type);
  73   if (TYPE_CODE (type) == TYPE_CODE_STRUCT && name != NULL
  74       && (i = strlen (name), name[i - 1] == ']'))
  75     {
  76       gdb_byte buf4[4];
  77       long length;
  78       unsigned int things_printed = 0;
  79       int reps;
  80       struct type *el_type
  81         = java_primitive_type_from_name (gdbarch, name, i - 2);
  82
  83       i = 0;
  84       read_memory (address + get_java_object_header_size (gdbarch), buf4, 4);
  85
  86       length = (long) extract_signed_integer (buf4, 4, byte_order);
  87       fprintf_filtered (stream, "{length: %ld", length);
  88
  89       if (el_type == NULL)
  90         {
  91           CORE_ADDR element;
  92           CORE_ADDR next_element = -1; /* Dummy initial value.  */
  93
  94           /* Skip object header and length.  */
  95           address += get_java_object_header_size (gdbarch) + 4;
  96
  97           while (i < length && things_printed < options->print_max)
  98             {
  99               gdb_byte *buf;
 100
 101               buf = alloca (gdbarch_ptr_bit (gdbarch) / HOST_CHAR_BIT);
 102               fputs_filtered (", ", stream);
 103               wrap_here (n_spaces (2));
 104
 105               if (i > 0)
 106                 element = next_element;
 107               else
 108                 {
 109                   read_memory (address, buf, sizeof (buf));
 110                   address += gdbarch_ptr_bit (gdbarch) / HOST_CHAR_BIT;
 111                   /* FIXME: cagney/2003-05-24: Bogus or what.  It
 112                      pulls a host sized pointer out of the target and
 113                      then extracts that as an address (while assuming
 114                      that the address is unsigned)!  */
 115                   element = extract_unsigned_integer (buf, sizeof (buf),
 116                                                       byte_order);
 117                 }
 118
 119               for (reps = 1; i + reps < length; reps++)
 120                 {
 121                   read_memory (address, buf, sizeof (buf));
 122                   address += gdbarch_ptr_bit (gdbarch) / HOST_CHAR_BIT;
 123                   /* FIXME: cagney/2003-05-24: Bogus or what.  It
 124                      pulls a host sized pointer out of the target and
 125                      then extracts that as an address (while assuming
 126                      that the address is unsigned)!  */
 127                   next_element = extract_unsigned_integer (buf, sizeof (buf),
 128                                                            byte_order);
 129                   if (next_element != element)
 130                     break;
 131                 }
 132
 133               if (reps == 1)
 134                 fprintf_filtered (stream, "%d: ", i);
 135               else
 136                 fprintf_filtered (stream, "%d..%d: ", i, i + reps - 1);
 137
 138               if (element == 0)
 139                 fprintf_filtered (stream, "null");
 140               else
 141                 fprintf_filtered (stream, "@%s", paddress (gdbarch, element));
 142
 143               things_printed++;
 144               i += reps;
 145             }
 146         }
 147       else
 148         {
 149           struct value *v = allocate_value (el_type);
 150           struct value *next_v = allocate_value (el_type);
 151
 152           set_value_address (v, (address
 153                                  + get_java_object_header_size (gdbarch) + 4));
 154           set_value_address (next_v, value_raw_address (v));
 155
 156           while (i < length && things_printed < options->print_max)
 157             {
 158               fputs_filtered (", ", stream);
 159               wrap_here (n_spaces (2));
 160
 161               if (i > 0)
 162                 {
 163                   struct value *tmp;
 164
 165                   tmp = next_v;
 166                   next_v = v;
 167                   v = tmp;
 168                 }
 169               else
 170                 {
 171                   set_value_lazy (v, 1);
 172                   set_value_offset (v, 0);
 173                 }
 174
 175               set_value_offset (next_v, value_offset (v));
 176
 177               for (reps = 1; i + reps < length; reps++)
 178                 {
 179                   set_value_lazy (next_v, 1);
 180                   set_value_offset (next_v, value_offset (next_v)
 181                                     + TYPE_LENGTH (el_type));
 182                   value_fetch_lazy (next_v);
 183                   if (!(value_available_contents_eq
 184                         (v, value_embedded_offset (v),
 185                          next_v, value_embedded_offset (next_v),
 186                          TYPE_LENGTH (el_type))))
 187                     break;
 188                 }
 189
 190               if (reps == 1)
 191                 fprintf_filtered (stream, "%d: ", i);
 192               else
 193                 fprintf_filtered (stream, "%d..%d: ", i, i + reps - 1);
 194
 195               opts = *options;
 196               opts.deref_ref = 1;
 197               common_val_print (v, stream, 1, &opts, current_language);
 198
 199               things_printed++;
 200               i += reps;
 201             }
 202         }
 203
 204       if (i < length)
 205         fprintf_filtered (stream, "...");
 206
 207       fprintf_filtered (stream, "}");
 208
 209       return 0;
 210     }
 211
 212   /* If it's type String, print it.  */
 213
 214   if (TYPE_CODE (type) == TYPE_CODE_PTR
 215       && TYPE_TARGET_TYPE (type)
 216       && TYPE_TAG_NAME (TYPE_TARGET_TYPE (type))
 217       && strcmp (TYPE_TAG_NAME (TYPE_TARGET_TYPE (type)),
 218                  "java.lang.String") == 0
 219       && (options->format == 0 || options->format == 's')
 220       && address != 0
 221       && value_as_address (val) != 0)
 222     {
 223       struct type *char_type;
 224       struct value *data_val;
 225       CORE_ADDR data;
 226       struct value *boffset_val;
 227       unsigned long boffset;
 228       struct value *count_val;
 229       unsigned long count;
 230       struct value *mark;
 231
 232       mark = value_mark ();     /* Remember start of new values.  */
 233
 234       data_val = value_struct_elt (&val, NULL, "data", NULL, NULL);
 235       data = value_as_address (data_val);
 236
 237       boffset_val = value_struct_elt (&val, NULL, "boffset", NULL, NULL);
 238       boffset = value_as_address (boffset_val);
 239
 240       count_val = value_struct_elt (&val, NULL, "count", NULL, NULL);
 241       count = value_as_address (count_val);
 242
 243       value_free_to_mark (mark);        /* Release unnecessary values.  */
 244
 245       char_type = builtin_java_type (gdbarch)->builtin_char;
 246       val_print_string (char_type, NULL, data + boffset, count, stream,
 247                         options);
 248
 249       return 0;
 250     }
 251
 252   opts = *options;
 253   opts.deref_ref = 1;
 254   return common_val_print (val, stream, 0, &opts, current_language);
 255 }
 256
 257 /* TYPE, VALADDR, ADDRESS, STREAM, RECURSE, and OPTIONS have the
 258    same meanings as in cp_print_value and c_val_print.
 259
 260    DONT_PRINT is an array of baseclass types that we
 261    should not print, or zero if called from top level.  */
 262
 263 static void
 264 java_print_value_fields (struct type *type, const gdb_byte *valaddr,
 265                          int offset,
 266                          CORE_ADDR address, struct ui_file *stream,
 267                          int recurse,
 268                          const struct value *val,
 269                          const struct value_print_options *options)
 270 {
 271   int i, len, n_baseclasses;
 272
 273   CHECK_TYPEDEF (type);
 274
 275   fprintf_filtered (stream, "{");
 276   len = TYPE_NFIELDS (type);
 277   n_baseclasses = TYPE_N_BASECLASSES (type);
 278
 279   if (n_baseclasses > 0)
 280     {
 281       int i, n_baseclasses = TYPE_N_BASECLASSES (type);
 282
 283       for (i = 0; i < n_baseclasses; i++)
 284         {
 285           int boffset;
 286           struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
 287           char *basename = TYPE_NAME (baseclass);
 288           const gdb_byte *base_valaddr;
 289
 290           if (BASETYPE_VIA_VIRTUAL (type, i))
 291             continue;
 292
 293           if (basename != NULL && strcmp (basename, "java.lang.Object") == 0)
 294             continue;
 295
 296           boffset = 0;
 297
 298           if (options->pretty)
 299             {
 300               fprintf_filtered (stream, "\n");
 301               print_spaces_filtered (2 * (recurse + 1), stream);
 302             }
 303           fputs_filtered ("<", stream);
 304           /* Not sure what the best notation is in the case where there is no
 305              baseclass name.  */
 306           fputs_filtered (basename ? basename : "", stream);
 307           fputs_filtered ("> = ", stream);
 308
 309           base_valaddr = valaddr;
 310
 311           java_print_value_fields (baseclass, base_valaddr,
 312                                    offset + boffset, address,
 313                                    stream, recurse + 1, val, options);
 314           fputs_filtered (", ", stream);
 315         }
 316     }
 317
 318   if (!len && n_baseclasses == 1)
 319     fprintf_filtered (stream, "<No data fields>");
 320   else
 321     {
 322       int fields_seen = 0;
 323
 324       for (i = n_baseclasses; i < len; i++)
 325         {
 326           /* If requested, skip printing of static fields.  */
 327           if (field_is_static (&TYPE_FIELD (type, i)))
 328             {
 329               char *name = TYPE_FIELD_NAME (type, i);
 330
 331               if (!options->static_field_print)
 332                 continue;
 333               if (name != NULL && strcmp (name, "class") == 0)
 334                 continue;
 335             }
 336           if (fields_seen)
 337             fprintf_filtered (stream, ", ");
 338           else if (n_baseclasses > 0)
 339             {
 340               if (options->pretty)
 341                 {
 342                   fprintf_filtered (stream, "\n");
 343                   print_spaces_filtered (2 + 2 * recurse, stream);
 344                   fputs_filtered ("members of ", stream);
 345                   fputs_filtered (type_name_no_tag (type), stream);
 346                   fputs_filtered (": ", stream);
 347                 }
 348             }
 349           fields_seen = 1;
 350
 351           if (options->pretty)
 352             {
 353               fprintf_filtered (stream, "\n");
 354               print_spaces_filtered (2 + 2 * recurse, stream);
 355             }
 356           else
 357             {
 358               wrap_here (n_spaces (2 + 2 * recurse));
 359             }
 360           if (options->inspect_it)
 361             {
 362               if (TYPE_CODE (TYPE_FIELD_TYPE (type, i)) == TYPE_CODE_PTR)
 363                 fputs_filtered ("\"( ptr \"", stream);
 364               else
 365                 fputs_filtered ("\"( nodef \"", stream);
 366               if (field_is_static (&TYPE_FIELD (type, i)))
 367                 fputs_filtered ("static ", stream);
 368               fprintf_symbol_filtered (stream, TYPE_FIELD_NAME (type, i),
 369                                        language_cplus,
 370                                        DMGL_PARAMS | DMGL_ANSI);
 371               fputs_filtered ("\" \"", stream);
 372               fprintf_symbol_filtered (stream, TYPE_FIELD_NAME (type, i),
 373                                        language_cplus,
 374                                        DMGL_PARAMS | DMGL_ANSI);
 375               fputs_filtered ("\") \"", stream);
 376             }
 377           else
 378             {
 379               annotate_field_begin (TYPE_FIELD_TYPE (type, i));
 380
 381               if (field_is_static (&TYPE_FIELD (type, i)))
 382                 fputs_filtered ("static ", stream);
 383               fprintf_symbol_filtered (stream, TYPE_FIELD_NAME (type, i),
 384                                        language_cplus,
 385                                        DMGL_PARAMS | DMGL_ANSI);
 386               annotate_field_name_end ();
 387               fputs_filtered (": ", stream);
 388               annotate_field_value ();
 389             }
 390
 391           if (!field_is_static (&TYPE_FIELD (type, i))
 392               && TYPE_FIELD_PACKED (type, i))
 393             {
 394               struct value *v;
 395
 396               /* Bitfields require special handling, especially due to byte
 397                  order problems.  */
 398               if (TYPE_FIELD_IGNORE (type, i))
 399                 {
 400                   fputs_filtered ("<optimized out or zero length>", stream);
 401                 }
 402               else if (value_bits_synthetic_pointer (val,
 403                                                      TYPE_FIELD_BITPOS (type,
 404                                                                         i),
 405                                                      TYPE_FIELD_BITSIZE (type,
 406                                                                          i)))
 407                 {
 408                   fputs_filtered (_("<synthetic pointer>"), stream);
 409                 }
 410               else if (!value_bits_valid (val, TYPE_FIELD_BITPOS (type, i),
 411                                           TYPE_FIELD_BITSIZE (type, i)))
 412                 {
 413                   val_print_optimized_out (stream);
 414                 }
 415               else
 416                 {
 417                   struct value_print_options opts;
 418
 419                   v = value_from_longest
 420                     (TYPE_FIELD_TYPE (type, i),
 421                      unpack_field_as_long (type, valaddr + offset, i));
 422
 423                   opts = *options;
 424                   opts.deref_ref = 0;
 425                   common_val_print (v, stream, recurse + 1,
 426                                     &opts, current_language);
 427                 }
 428             }
 429           else
 430             {
 431               if (TYPE_FIELD_IGNORE (type, i))
 432                 {
 433                   fputs_filtered ("<optimized out or zero length>", stream);
 434                 }
 435               else if (field_is_static (&TYPE_FIELD (type, i)))
 436                 {
 437                   struct value *v = value_static_field (type, i);
 438
 439                   if (v == NULL)
 440                     val_print_optimized_out (stream);
 441                   else
 442                     {
 443                       struct value_print_options opts;
 444                       struct type *t = check_typedef (value_type (v));
 445
 446                       if (TYPE_CODE (t) == TYPE_CODE_STRUCT)
 447                         v = value_addr (v);
 448                       opts = *options;
 449                       opts.deref_ref = 0;
 450                       common_val_print (v, stream, recurse + 1,
 451                                         &opts, current_language);
 452                     }
 453                 }
 454               else if (TYPE_FIELD_TYPE (type, i) == NULL)
 455                 fputs_filtered ("<unknown type>", stream);
 456               else
 457                 {
 458                   struct value_print_options opts = *options;
 459
 460                   opts.deref_ref = 0;
 461                   val_print (TYPE_FIELD_TYPE (type, i),
 462                              valaddr,
 463                              offset + TYPE_FIELD_BITPOS (type, i) / 8,
 464                              address, stream, recurse + 1, val, &opts,
 465                              current_language);
 466                 }
 467             }
 468           annotate_field_end ();
 469         }
 470
 471       if (options->pretty)
 472         {
 473           fprintf_filtered (stream, "\n");
 474           print_spaces_filtered (2 * recurse, stream);
 475         }
 476     }
 477   fprintf_filtered (stream, "}");
 478 }
 479
 480 /* See val_print for a description of the various parameters of this
 481    function; they are identical.  The semantics of the return value is
 482    also identical to val_print.  */
 483
 484 int
 485 java_val_print (struct type *type, const gdb_byte *valaddr,
 486                 int embedded_offset, CORE_ADDR address,
 487                 struct ui_file *stream, int recurse,
 488                 const struct value *val,
 489                 const struct value_print_options *options)
 490 {
 491   struct gdbarch *gdbarch = get_type_arch (type);
 492   unsigned int i = 0;   /* Number of characters printed.  */
 493   struct type *target_type;
 494   CORE_ADDR addr;
 495
 496   CHECK_TYPEDEF (type);
 497   switch (TYPE_CODE (type))
 498     {
 499     case TYPE_CODE_PTR:
 500       if (options->format && options->format != 's')
 501         {
 502           val_print_scalar_formatted (type, valaddr, embedded_offset,
 503                                       val, options, 0, stream);
 504           break;
 505         }
 506 #if 0
 507       if (options->vtblprint && cp_is_vtbl_ptr_type (type))
 508         {
 509           /* Print the unmangled name if desired.  */
 510           /* Print vtable entry - we only get here if we ARE using
 511              -fvtable_thunks.  (Otherwise, look under TYPE_CODE_STRUCT.)  */
 512           /* Extract an address, assume that it is unsigned.  */
 513           print_address_demangle
 514             (gdbarch,
 515              extract_unsigned_integer (valaddr + embedded_offset,
 516                                        TYPE_LENGTH (type)),
 517              stream, demangle);
 518           break;
 519         }
 520 #endif
 521       addr = unpack_pointer (type, valaddr + embedded_offset);
 522       if (addr == 0)
 523         {
 524           fputs_filtered ("null", stream);
 525           return i;
 526         }
 527       target_type = check_typedef (TYPE_TARGET_TYPE (type));
 528
 529       if (TYPE_CODE (target_type) == TYPE_CODE_FUNC)
 530         {
 531           /* Try to print what function it points to.  */
 532           print_address_demangle (gdbarch, addr, stream, demangle);
 533           /* Return value is irrelevant except for string pointers.  */
 534           return (0);
 535         }
 536
 537       if (options->addressprint && options->format != 's')
 538         {
 539           fputs_filtered ("@", stream);
 540           print_longest (stream, 'x', 0, (ULONGEST) addr);
 541         }
 542
 543       return i;
 544
 545     case TYPE_CODE_CHAR:
 546     case TYPE_CODE_INT:
 547       /* Can't just call c_val_print because that prints bytes as C
 548          chars.  */
 549       if (options->format || options->output_format)
 550         {
 551           struct value_print_options opts = *options;
 552
 553           opts.format = (options->format ? options->format
 554                          : options->output_format);
 555           val_print_scalar_formatted (type, valaddr, embedded_offset,
 556                                       val, &opts, 0, stream);
 557         }
 558       else if (TYPE_CODE (type) == TYPE_CODE_CHAR
 559                || (TYPE_CODE (type) == TYPE_CODE_INT
 560                    && TYPE_LENGTH (type) == 2
 561                    && strcmp (TYPE_NAME (type), "char") == 0))
 562         LA_PRINT_CHAR ((int) unpack_long (type, valaddr + embedded_offset),
 563                        type, stream);
 564       else
 565         val_print_type_code_int (type, valaddr + embedded_offset, stream);
 566       break;
 567
 568     case TYPE_CODE_STRUCT:
 569       java_print_value_fields (type, valaddr, embedded_offset,
 570                                address, stream, recurse, val, options);
 571       break;
 572
 573     default:
 574       return c_val_print (type, valaddr, embedded_offset, address, stream,
 575                           recurse, val, options);
 576     }
 577
 578   return 0;
 579 }