gdb/jv-valprint.c

   1 /* Support for printing Java values for GDB, the GNU debugger.
   2
   3    Copyright (C) 1997-2016 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   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.
  11
  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.
  16
  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/>.  */
  19
  20 #include "defs.h"
  21 #include "symtab.h"
  22 #include "gdbtypes.h"
  23 #include "gdbcore.h"
  24 #include "expression.h"
  25 #include "value.h"
  26 #include "demangle.h"
  27 #include "valprint.h"
  28 #include "language.h"
  29 #include "jv-lang.h"
  30 #include "c-lang.h"
  31 #include "annotate.h"
  32 /* Local functions */
  33
  34 void
  35 java_value_print (struct value *val, struct ui_file *stream,
  36                   const struct value_print_options *options)
  37 {
  38   struct gdbarch *gdbarch = get_type_arch (value_type (val));
  39   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
  40   struct type *type;
  41   CORE_ADDR address;
  42   int i;
  43   const char *name;
  44   struct value_print_options opts;
  45
  46   type = value_type (val);
  47   address = value_address (val);
  48
  49   if (is_object_type (type))
  50     {
  51       CORE_ADDR obj_addr;
  52       struct value *tem = val;
  53
  54       /* Get the run-time type, and cast the object into that.  */
  55       while (TYPE_CODE (value_type (tem)) == TYPE_CODE_PTR)
  56         tem = value_ind (tem);
  57
  58       obj_addr = value_address (tem);
  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           type = value_type (val);
  67         }
  68     }
  69
  70   if (TYPE_CODE (type) == TYPE_CODE_PTR && !value_logical_not (val))
  71     type_print (TYPE_TARGET_TYPE (type), "", stream, -1);
  72
  73   name = TYPE_TAG_NAME (type);
  74   if (TYPE_CODE (type) == TYPE_CODE_STRUCT && name != NULL
  75       && (i = strlen (name), name[i - 1] == ']'))
  76     {
  77       gdb_byte buf4[4];
  78       long length;
  79       unsigned int things_printed = 0;
  80       int reps;
  81       struct type *el_type
  82         = java_primitive_type_from_name (gdbarch, name, i - 2);
  83
  84       i = 0;
  85       read_memory (address + get_java_object_header_size (gdbarch), buf4, 4);
  86
  87       length = (long) extract_signed_integer (buf4, 4, byte_order);
  88       fprintf_filtered (stream, "{length: %ld", length);
  89
  90       if (el_type == NULL)
  91         {
  92           CORE_ADDR element;
  93           CORE_ADDR next_element = -1; /* Dummy initial value.  */
  94
  95           /* Skip object header and length.  */
  96           address += get_java_object_header_size (gdbarch) + 4;
  97
  98           while (i < length && things_printed < options->print_max)
  99             {
 100               gdb_byte *buf;
 101
 102               buf = ((gdb_byte *)
 103                      alloca (gdbarch_ptr_bit (gdbarch) / HOST_CHAR_BIT));
 104               fputs_filtered (", ", stream);
 105               wrap_here (n_spaces (2));
 106
 107               if (i > 0)
 108                 element = next_element;
 109               else
 110                 {
 111                   read_memory (address, buf, sizeof (buf));
 112                   address += gdbarch_ptr_bit (gdbarch) / HOST_CHAR_BIT;
 113                   /* FIXME: cagney/2003-05-24: Bogus or what.  It
 114                      pulls a host sized pointer out of the target and
 115                      then extracts that as an address (while assuming
 116                      that the address is unsigned)!  */
 117                   element = extract_unsigned_integer (buf, sizeof (buf),
 118                                                       byte_order);
 119                 }
 120
 121               for (reps = 1; i + reps < length; reps++)
 122                 {
 123                   read_memory (address, buf, sizeof (buf));
 124                   address += gdbarch_ptr_bit (gdbarch) / HOST_CHAR_BIT;
 125                   /* FIXME: cagney/2003-05-24: Bogus or what.  It
 126                      pulls a host sized pointer out of the target and
 127                      then extracts that as an address (while assuming
 128                      that the address is unsigned)!  */
 129                   next_element = extract_unsigned_integer (buf, sizeof (buf),
 130                                                            byte_order);
 131                   if (next_element != element)
 132                     break;
 133                 }
 134
 135               if (reps == 1)
 136                 fprintf_filtered (stream, "%d: ", i);
 137               else
 138                 fprintf_filtered (stream, "%d..%d: ", i, i + reps - 1);
 139
 140               if (element == 0)
 141                 fprintf_filtered (stream, "null");
 142               else
 143                 fprintf_filtered (stream, "@%s", paddress (gdbarch, element));
 144
 145               things_printed++;
 146               i += reps;
 147             }
 148         }
 149       else
 150         {
 151           struct value *v = allocate_value (el_type);
 152           struct value *next_v = allocate_value (el_type);
 153
 154           set_value_address (v, (address
 155                                  + get_java_object_header_size (gdbarch) + 4));
 156           set_value_address (next_v, value_raw_address (v));
 157
 158           while (i < length && things_printed < options->print_max)
 159             {
 160               fputs_filtered (", ", stream);
 161               wrap_here (n_spaces (2));
 162
 163               if (i > 0)
 164                 {
 165                   struct value *tmp;
 166
 167                   tmp = next_v;
 168                   next_v = v;
 169                   v = tmp;
 170                 }
 171               else
 172                 {
 173                   set_value_lazy (v, 1);
 174                   set_value_offset (v, 0);
 175                 }
 176
 177               set_value_offset (next_v, value_offset (v));
 178
 179               for (reps = 1; i + reps < length; reps++)
 180                 {
 181                   set_value_lazy (next_v, 1);
 182                   set_value_offset (next_v, value_offset (next_v)
 183                                     + TYPE_LENGTH (el_type));
 184                   value_fetch_lazy (next_v);
 185                   if (!value_contents_eq (v, value_embedded_offset (v),
 186                                           next_v,
 187                                           value_embedded_offset (next_v),
 188                                           TYPE_LENGTH (el_type)))
 189                     break;
 190                 }
 191
 192               if (reps == 1)
 193                 fprintf_filtered (stream, "%d: ", i);
 194               else
 195                 fprintf_filtered (stream, "%d..%d: ", i, i + reps - 1);
 196
 197               opts = *options;
 198               opts.deref_ref = 1;
 199               common_val_print (v, stream, 1, &opts, current_language);
 200
 201               things_printed++;
 202               i += reps;
 203             }
 204         }
 205
 206       if (i < length)
 207         fprintf_filtered (stream, "...");
 208
 209       fprintf_filtered (stream, "}");
 210
 211       return;
 212     }
 213
 214   /* If it's type String, print it.  */
 215
 216   if (TYPE_CODE (type) == TYPE_CODE_PTR
 217       && TYPE_TARGET_TYPE (type)
 218       && TYPE_TAG_NAME (TYPE_TARGET_TYPE (type))
 219       && strcmp (TYPE_TAG_NAME (TYPE_TARGET_TYPE (type)),
 220                  "java.lang.String") == 0
 221       && (options->format == 0 || options->format == 's')
 222       && address != 0
 223       && value_as_address (val) != 0)
 224     {
 225       struct type *char_type;
 226       struct value *data_val;
 227       CORE_ADDR data;
 228       struct value *boffset_val;
 229       unsigned long boffset;
 230       struct value *count_val;
 231       unsigned long count;
 232       struct value *mark;
 233
 234       fputs_filtered (" ", stream);
 235
 236       mark = value_mark ();     /* Remember start of new values.  */
 237
 238       data_val = value_struct_elt (&val, NULL, "data", NULL, NULL);
 239       data = value_as_address (data_val);
 240
 241       boffset_val = value_struct_elt (&val, NULL, "boffset", NULL, NULL);
 242       boffset = value_as_address (boffset_val);
 243
 244       count_val = value_struct_elt (&val, NULL, "count", NULL, NULL);
 245       count = value_as_address (count_val);
 246
 247       value_free_to_mark (mark);        /* Release unnecessary values.  */
 248
 249       char_type = builtin_java_type (gdbarch)->builtin_char;
 250       val_print_string (char_type, NULL, data + boffset, count, stream,
 251                         options);
 252
 253       return;
 254     }
 255
 256   opts = *options;
 257   opts.deref_ref = 1;
 258   common_val_print (val, stream, 0, &opts, current_language);
 259 }
 260
 261 /* TYPE, VALADDR, ADDRESS, STREAM, RECURSE, and OPTIONS have the
 262    same meanings as in cp_print_value and c_val_print.
 263
 264    DONT_PRINT is an array of baseclass types that we
 265    should not print, or zero if called from top level.  */
 266
 267 static void
 268 java_print_value_fields (struct type *type, const gdb_byte *valaddr,
 269                          LONGEST offset,
 270                          CORE_ADDR address, struct ui_file *stream,
 271                          int recurse,
 272                          const struct value *val,
 273                          const struct value_print_options *options)
 274 {
 275   int i, len, n_baseclasses;
 276
 277   type = check_typedef (type);
 278
 279   fprintf_filtered (stream, "{");
 280   len = TYPE_NFIELDS (type);
 281   n_baseclasses = TYPE_N_BASECLASSES (type);
 282
 283   if (n_baseclasses > 0)
 284     {
 285       int i, n_baseclasses = TYPE_N_BASECLASSES (type);
 286
 287       for (i = 0; i < n_baseclasses; i++)
 288         {
 289           int boffset;
 290           struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
 291           const char *basename = TYPE_NAME (baseclass);
 292           const gdb_byte *base_valaddr;
 293
 294           if (BASETYPE_VIA_VIRTUAL (type, i))
 295             continue;
 296
 297           if (basename != NULL && strcmp (basename, "java.lang.Object") == 0)
 298             continue;
 299
 300           boffset = 0;
 301
 302           if (options->prettyformat)
 303             {
 304               fprintf_filtered (stream, "\n");
 305               print_spaces_filtered (2 * (recurse + 1), stream);
 306             }
 307           fputs_filtered ("<", stream);
 308           /* Not sure what the best notation is in the case where there is no
 309              baseclass name.  */
 310           fputs_filtered (basename ? basename : "", stream);
 311           fputs_filtered ("> = ", stream);
 312
 313           base_valaddr = valaddr;
 314
 315           java_print_value_fields (baseclass, base_valaddr,
 316                                    offset + boffset, address,
 317                                    stream, recurse + 1, val, options);
 318           fputs_filtered (", ", stream);
 319         }
 320     }
 321
 322   if (!len && n_baseclasses == 1)
 323     fprintf_filtered (stream, "<No data fields>");
 324   else
 325     {
 326       int fields_seen = 0;
 327
 328       for (i = n_baseclasses; i < len; i++)
 329         {
 330           /* If requested, skip printing of static fields.  */
 331           if (field_is_static (&TYPE_FIELD (type, i)))
 332             {
 333               const char *name = TYPE_FIELD_NAME (type, i);
 334
 335               if (!options->static_field_print)
 336                 continue;
 337               if (name != NULL && strcmp (name, "class") == 0)
 338                 continue;
 339             }
 340           if (fields_seen)
 341             fprintf_filtered (stream, ", ");
 342           else if (n_baseclasses > 0)
 343             {
 344               if (options->prettyformat)
 345                 {
 346                   fprintf_filtered (stream, "\n");
 347                   print_spaces_filtered (2 + 2 * recurse, stream);
 348                   fputs_filtered ("members of ", stream);
 349                   fputs_filtered (type_name_no_tag (type), stream);
 350                   fputs_filtered (": ", stream);
 351                 }
 352             }
 353           fields_seen = 1;
 354
 355           if (options->prettyformat)
 356             {
 357               fprintf_filtered (stream, "\n");
 358               print_spaces_filtered (2 + 2 * recurse, stream);
 359             }
 360           else
 361             {
 362               wrap_here (n_spaces (2 + 2 * recurse));
 363             }
 364
 365           annotate_field_begin (TYPE_FIELD_TYPE (type, i));
 366
 367           if (field_is_static (&TYPE_FIELD (type, i)))
 368             fputs_filtered ("static ", stream);
 369           fprintf_symbol_filtered (stream, TYPE_FIELD_NAME (type, i),
 370                                    language_cplus,
 371                                    DMGL_PARAMS | DMGL_ANSI);
 372           annotate_field_name_end ();
 373           fputs_filtered (": ", stream);
 374           annotate_field_value ();
 375
 376           if (!field_is_static (&TYPE_FIELD (type, i))
 377               && TYPE_FIELD_PACKED (type, i))
 378             {
 379               struct value *v;
 380
 381               /* Bitfields require special handling, especially due to byte
 382                  order problems.  */
 383               if (TYPE_FIELD_IGNORE (type, i))
 384                 {
 385                   fputs_filtered ("<optimized out or zero length>", stream);
 386                 }
 387               else if (value_bits_synthetic_pointer (val,
 388                                                      TYPE_FIELD_BITPOS (type,
 389                                                                         i),
 390                                                      TYPE_FIELD_BITSIZE (type,
 391                                                                          i)))
 392                 {
 393                   fputs_filtered (_("<synthetic pointer>"), stream);
 394                 }
 395               else
 396                 {
 397                   struct value_print_options opts;
 398
 399                   v = value_field_bitfield (type, i, valaddr, offset, val);
 400
 401                   opts = *options;
 402                   opts.deref_ref = 0;
 403                   common_val_print (v, stream, recurse + 1,
 404                                     &opts, current_language);
 405                 }
 406             }
 407           else
 408             {
 409               if (TYPE_FIELD_IGNORE (type, i))
 410                 {
 411                   fputs_filtered ("<optimized out or zero length>", stream);
 412                 }
 413               else if (field_is_static (&TYPE_FIELD (type, i)))
 414                 {
 415                   struct value_print_options opts;
 416                   struct value *v = value_static_field (type, i);
 417                   struct type *t = check_typedef (value_type (v));
 418
 419                   if (TYPE_CODE (t) == TYPE_CODE_STRUCT)
 420                     v = value_addr (v);
 421                   opts = *options;
 422                   opts.deref_ref = 0;
 423                   common_val_print (v, stream, recurse + 1,
 424                                     &opts, current_language);
 425                 }
 426               else if (TYPE_FIELD_TYPE (type, i) == NULL)
 427                 fputs_filtered ("<unknown type>", stream);
 428               else
 429                 {
 430                   struct value_print_options opts = *options;
 431
 432                   opts.deref_ref = 0;
 433                   val_print (TYPE_FIELD_TYPE (type, i),
 434                              valaddr,
 435                              offset + TYPE_FIELD_BITPOS (type, i) / 8,
 436                              address, stream, recurse + 1, val, &opts,
 437                              current_language);
 438                 }
 439             }
 440           annotate_field_end ();
 441         }
 442
 443       if (options->prettyformat)
 444         {
 445           fprintf_filtered (stream, "\n");
 446           print_spaces_filtered (2 * recurse, stream);
 447         }
 448     }
 449   fprintf_filtered (stream, "}");
 450 }
 451
 452 /* See val_print for a description of the various parameters of this
 453    function; they are identical.  */
 454
 455 void
 456 java_val_print (struct type *type, const gdb_byte *valaddr,
 457                 int embedded_offset, CORE_ADDR address,
 458                 struct ui_file *stream, int recurse,
 459                 const struct value *val,
 460                 const struct value_print_options *options)
 461 {
 462   struct gdbarch *gdbarch = get_type_arch (type);
 463   struct type *target_type;
 464   CORE_ADDR addr;
 465
 466   type = check_typedef (type);
 467   switch (TYPE_CODE (type))
 468     {
 469     case TYPE_CODE_PTR:
 470       if (options->format && options->format != 's')
 471         {
 472           val_print_scalar_formatted (type, valaddr, embedded_offset,
 473                                       val, options, 0, stream);
 474           break;
 475         }
 476       addr = unpack_pointer (type, valaddr + embedded_offset);
 477       if (addr == 0)
 478         {
 479           fputs_filtered ("null", stream);
 480           return;
 481         }
 482       target_type = check_typedef (TYPE_TARGET_TYPE (type));
 483
 484       if (TYPE_CODE (target_type) == TYPE_CODE_FUNC)
 485         {
 486           /* Try to print what function it points to.  */
 487           print_address_demangle (options, gdbarch, addr, stream, demangle);
 488           return;
 489         }
 490
 491       if (options->addressprint && options->format != 's')
 492         {
 493           fputs_filtered ("@", stream);
 494           print_longest (stream, 'x', 0, (ULONGEST) addr);
 495         }
 496
 497       return;
 498
 499     case TYPE_CODE_CHAR:
 500     case TYPE_CODE_INT:
 501       /* Can't just call c_val_print because that prints bytes as C
 502          chars.  */
 503       if (options->format || options->output_format)
 504         {
 505           struct value_print_options opts = *options;
 506
 507           opts.format = (options->format ? options->format
 508                          : options->output_format);
 509           val_print_scalar_formatted (type, valaddr, embedded_offset,
 510                                       val, &opts, 0, stream);
 511         }
 512       else if (TYPE_CODE (type) == TYPE_CODE_CHAR
 513                || (TYPE_CODE (type) == TYPE_CODE_INT
 514                    && TYPE_LENGTH (type) == 2
 515                    && strcmp (TYPE_NAME (type), "char") == 0))
 516         LA_PRINT_CHAR ((int) unpack_long (type, valaddr + embedded_offset),
 517                        type, stream);
 518       else
 519         val_print_type_code_int (type, valaddr + embedded_offset, stream);
 520       break;
 521
 522     case TYPE_CODE_STRUCT:
 523       java_print_value_fields (type, valaddr, embedded_offset,
 524                                address, stream, recurse, val, options);
 525       break;
 526
 527     default:
 528       c_val_print (type, valaddr, embedded_offset, address, stream,
 529                    recurse, val, options);
 530       break;
 531     }
 532 }