mono/metadata/debug-mono-symfile.c

   1 /*
   2  * debug-mono-symfile.c:
   3  *
   4  * Author:
   5  *      Mono Project (http://www.mono-project.com)
   6  *
   7  * Copyright (C) 2005-2008 Novell, Inc. (http://www.novell.com)
   8  */
   9
  10 #include <config.h>
  11 #include <stdlib.h>
  12 #include <stdio.h>
  13 #include <errno.h>
  14 #include <string.h>
  15 #ifdef HAVE_SYS_PARAM_H
  16 #include <sys/param.h>
  17 #endif
  18 #include <sys/stat.h>
  19 #include <mono/metadata/metadata.h>
  20 #include <mono/metadata/tabledefs.h>
  21 #include <mono/metadata/tokentype.h>
  22 #include <mono/metadata/appdomain.h>
  23 #include <mono/metadata/exception.h>
  24 #include <mono/metadata/debug-helpers.h>
  25 #include <mono/metadata/mono-debug.h>
  26 #include <mono/metadata/debug-mono-symfile.h>
  27 #include <mono/metadata/mono-debug-debugger.h>
  28 #include <mono/metadata/mono-endian.h>
  29 #include <mono/metadata/metadata-internals.h>
  30 #include <mono/metadata/class-internals.h>
  31 #include <mono/utils/mono-mmap.h>
  32
  33 #include <fcntl.h>
  34 #ifdef HAVE_UNISTD_H
  35 #include <unistd.h>
  36 #endif
  37
  38 #define RANGE_TABLE_CHUNK_SIZE          256
  39 #define CLASS_TABLE_CHUNK_SIZE          256
  40 #define TYPE_TABLE_PTR_CHUNK_SIZE       256
  41 #define TYPE_TABLE_CHUNK_SIZE           65536
  42
  43 static void
  44 free_method_info (MonoDebugMethodInfo *minfo)
  45 {
  46         g_free (minfo);
  47 }
  48
  49 static int
  50 load_symfile (MonoDebugHandle *handle, MonoSymbolFile *symfile, gboolean in_the_debugger)
  51 {
  52         const char *ptr, *start;
  53         gchar *guid;
  54         guint64 magic;
  55         int minor, major;
  56
  57         ptr = start = (const char*)symfile->raw_contents;
  58         if (!ptr)
  59                 return FALSE;
  60
  61         magic = read64(ptr);
  62         ptr += sizeof(guint64);
  63         if (magic != MONO_SYMBOL_FILE_MAGIC) {
  64                 if (!in_the_debugger)
  65                         g_warning ("Symbol file %s is not a mono symbol file", symfile->filename);
  66                 return FALSE;
  67         }
  68
  69         major = read32(ptr);
  70         ptr += sizeof(guint32);
  71         minor = read32(ptr);
  72         ptr += sizeof(guint32);
  73
  74         /*
  75          * 50.0 is the frozen version for Mono 2.0.
  76          *
  77          * Nobody except me (Martin) is allowed to check the minor version.
  78          */
  79         if (major != MONO_SYMBOL_FILE_MAJOR_VERSION) {
  80                 if (!in_the_debugger)
  81                         g_warning ("Symbol file %s has incorrect version (expected %d.%d, got %d)",
  82                                    symfile->filename, MONO_SYMBOL_FILE_MAJOR_VERSION,
  83                                    MONO_SYMBOL_FILE_MINOR_VERSION, major);
  84                 return FALSE;
  85         }
  86
  87         guid = mono_guid_to_string ((const guint8 *) ptr);
  88         ptr += 16;
  89
  90         if (strcmp (handle->image->guid, guid)) {
  91                 if (!in_the_debugger)
  92                         g_warning ("Symbol file %s doesn't match image %s", symfile->filename,
  93                                    handle->image_file);
  94                 if (guid)
  95                         g_free (guid);
  96                 return FALSE;
  97         }
  98
  99         symfile->major_version = major;
 100         symfile->minor_version = minor;
 101
 102         symfile->offset_table = (MonoSymbolFileOffsetTable *) ptr;
 103
 104         symfile->method_hash = g_hash_table_new_full (
 105                 g_direct_hash, g_direct_equal, NULL, (GDestroyNotify) free_method_info);
 106
 107         g_free (guid);
 108         return TRUE;
 109 }
 110
 111 MonoSymbolFile *
 112 mono_debug_open_mono_symbols (MonoDebugHandle *handle, const guint8 *raw_contents,
 113                               int size, gboolean in_the_debugger)
 114 {
 115         MonoSymbolFile *symfile;
 116
 117         mono_debugger_lock ();
 118         symfile = g_new0 (MonoSymbolFile, 1);
 119
 120         if (raw_contents != NULL) {
 121                 unsigned char *p;
 122                 symfile->raw_contents_size = size;
 123                 symfile->raw_contents = p = g_malloc (size);
 124                 memcpy (p, raw_contents, size);
 125                 symfile->filename = g_strdup_printf ("LoadedFromMemory");
 126                 symfile->was_loaded_from_memory = TRUE;
 127         } else {
 128                 MonoFileMap *f;
 129                 symfile->filename = g_strdup_printf ("%s.mdb", mono_image_get_filename (handle->image));
 130                 symfile->was_loaded_from_memory = FALSE;
 131                 if ((f = mono_file_map_open (symfile->filename))) {
 132                         symfile->raw_contents_size = mono_file_map_size (f);
 133                         if (symfile->raw_contents_size == 0) {
 134                                 if (!in_the_debugger)
 135                                         g_warning ("stat of %s failed: %s",
 136                                                    symfile->filename,  g_strerror (errno));
 137                         } else {
 138                                 symfile->raw_contents = mono_file_map (symfile->raw_contents_size, MONO_MMAP_READ|MONO_MMAP_PRIVATE, mono_file_map_fd (f), 0, &symfile->raw_contents_handle);
 139                         }
 140
 141                         mono_file_map_close (f);
 142                 }
 143         }
 144
 145         if (load_symfile (handle, symfile, in_the_debugger)) {
 146                 mono_debugger_unlock ();
 147                 return symfile;
 148         } else if (!in_the_debugger) {
 149                 mono_debug_close_mono_symbol_file (symfile);
 150                 mono_debugger_unlock ();
 151                 return NULL;
 152         }
 153
 154         mono_debugger_unlock ();
 155         return symfile;
 156 }
 157
 158 void
 159 mono_debug_close_mono_symbol_file (MonoSymbolFile *symfile)
 160 {
 161         if (!symfile)
 162                 return;
 163
 164         mono_debugger_lock ();
 165         if (symfile->method_hash)
 166                 g_hash_table_destroy (symfile->method_hash);
 167
 168         if (symfile->raw_contents) {
 169                 if (symfile->was_loaded_from_memory)
 170                         g_free ((gpointer)symfile->raw_contents);
 171                 else
 172                         mono_file_unmap ((gpointer) symfile->raw_contents, symfile->raw_contents_handle);
 173         }
 174
 175         if (symfile->filename)
 176                 g_free (symfile->filename);
 177         g_free (symfile);
 178         mono_debugger_unlock ();
 179 }
 180
 181 static int
 182 read_leb128 (const guint8 *ptr, const guint8 **rptr)
 183 {
 184         int ret = 0;
 185         int shift = 0;
 186         char b;
 187
 188         do {
 189                 b = *ptr++;
 190
 191                 ret = ret | ((b & 0x7f) << shift);
 192                 shift += 7;
 193         } while ((b & 0x80) == 0x80);
 194
 195         if (rptr)
 196                 *rptr = ptr;
 197
 198         return ret;
 199 }
 200
 201 static gchar *
 202 read_string (const guint8 *ptr)
 203 {
 204         int len = read_leb128 (ptr, &ptr);
 205         return g_filename_from_utf8 ((const char *) ptr, len, NULL, NULL, NULL);
 206 }
 207
 208 typedef struct {
 209         MonoSymbolFile *symfile;
 210         int line_base, line_range, max_address_incr;
 211         guint8 opcode_base;
 212         guint32 last_line, last_file, last_offset;
 213         guint32 first_file;
 214         int line, file, offset;
 215         gboolean is_hidden;
 216 } StatementMachine;
 217
 218 static gboolean
 219 check_line (StatementMachine *stm, int offset, MonoDebugSourceLocation **location)
 220 {
 221         gchar *source_file = NULL;
 222
 223         if (stm->offset <= offset) {
 224                 stm->last_offset = stm->offset;
 225                 stm->last_file = stm->file;
 226                 if (stm->line != 0xfeefee)
 227                         stm->last_line = stm->line;
 228                 return FALSE;
 229         }
 230
 231         if (stm->last_file) {
 232                 int offset = read32(&(stm->symfile->offset_table->_source_table_offset)) +
 233                         (stm->last_file - 1) * sizeof (MonoSymbolFileSourceEntry);
 234                 MonoSymbolFileSourceEntry *se = (MonoSymbolFileSourceEntry *)
 235                         (stm->symfile->raw_contents + offset);
 236
 237                 source_file = read_string (stm->symfile->raw_contents + read32(&(se->_data_offset)));
 238         }
 239
 240         if (stm->last_line == 0) {
 241                 /*
 242                  * The IL offset is less than the first IL offset which has a corresponding
 243                  * source line.
 244                  */
 245                 *location = NULL;
 246                 return TRUE;
 247         }
 248
 249         *location = g_new0 (MonoDebugSourceLocation, 1);
 250         (*location)->source_file = source_file;
 251         (*location)->row = stm->last_line;
 252         (*location)->il_offset = stm->last_offset;
 253         return TRUE;
 254 }
 255
 256 /**
 257  * mono_debug_symfile_lookup_location:
 258  * @minfo: A `MonoDebugMethodInfo' which can be retrieved by
 259  *         mono_debug_lookup_method().
 260  * @offset: IL offset within the corresponding method's CIL code.
 261  *
 262  * This function is similar to mono_debug_lookup_location(), but we
 263  * already looked up the method and also already did the
 264  * `native address -> IL offset' mapping.
 265  */
 266 MonoDebugSourceLocation *
 267 mono_debug_symfile_lookup_location (MonoDebugMethodInfo *minfo, guint32 offset)
 268 {
 269         MonoDebugSourceLocation *location = NULL;
 270         MonoSymbolFile *symfile;
 271         const unsigned char *ptr;
 272         StatementMachine stm;
 273
 274 #define DW_LNS_copy 1
 275 #define DW_LNS_advance_pc 2
 276 #define DW_LNS_advance_line 3
 277 #define DW_LNS_set_file 4
 278 #define DW_LNS_const_add_pc 8
 279
 280 #define DW_LNE_end_sequence 1
 281 #define DW_LNE_MONO_negate_is_hidden 0x40
 282
 283 #define DW_LNE_MONO__extensions_start 0x40
 284 #define DW_LNE_MONO__extensions_end 0x7f
 285
 286         if ((symfile = minfo->handle->symfile) == NULL)
 287                 return NULL;
 288
 289         stm.line_base = read32 (&symfile->offset_table->_line_number_table_line_base);
 290         stm.line_range = read32 (&symfile->offset_table->_line_number_table_line_range);
 291         stm.opcode_base = (guint8) read32 (&symfile->offset_table->_line_number_table_opcode_base);
 292         stm.max_address_incr = (255 - stm.opcode_base) / stm.line_range;
 293
 294         mono_debugger_lock ();
 295
 296         ptr = symfile->raw_contents + minfo->lnt_offset;
 297
 298         stm.symfile = symfile;
 299         stm.offset = stm.last_offset = 0;
 300         stm.last_file = 0;
 301         stm.last_line = 0;
 302         stm.first_file = 0;
 303         stm.file = 1;
 304         stm.line = 1;
 305         stm.is_hidden = FALSE;
 306
 307         while (TRUE) {
 308                 guint8 opcode = *ptr++;
 309
 310                 if (opcode == 0) {
 311                         guint8 size = *ptr++;
 312                         const unsigned char *end_ptr = ptr + size;
 313
 314                         opcode = *ptr++;
 315
 316                         if (opcode == DW_LNE_end_sequence) {
 317                                 if (check_line (&stm, -1, &location))
 318                                         goto out_success;
 319                                 break;
 320                         } else if (opcode == DW_LNE_MONO_negate_is_hidden) {
 321                                 stm.is_hidden = !stm.is_hidden;
 322                         } else if ((opcode >= DW_LNE_MONO__extensions_start) &&
 323                                    (opcode <= DW_LNE_MONO__extensions_end)) {
 324                                 ; // reserved for future extensions
 325                         } else {
 326                                 g_warning ("Unknown extended opcode %x in LNT", opcode);
 327                         }
 328
 329                         ptr = end_ptr;
 330                         continue;
 331                 } else if (opcode < stm.opcode_base) {
 332                         switch (opcode) {
 333                         case DW_LNS_copy:
 334                                 if (check_line (&stm, offset, &location))
 335                                         goto out_success;
 336                                 break;
 337                         case DW_LNS_advance_pc:
 338                                 stm.offset += read_leb128 (ptr, &ptr);
 339                                 break;
 340                         case DW_LNS_advance_line:
 341                                 stm.line += read_leb128 (ptr, &ptr);
 342                                 break;
 343                         case DW_LNS_set_file:
 344                                 stm.file = read_leb128 (ptr, &ptr);
 345                                 break;
 346                         case DW_LNS_const_add_pc:
 347                                 stm.offset += stm.max_address_incr;
 348                                 break;
 349                         default:
 350                                 g_warning ("Unknown standard opcode %x in LNT", opcode);
 351                                 goto error_out;
 352                         }
 353                 } else {
 354                         opcode -= stm.opcode_base;
 355
 356                         stm.offset += opcode / stm.line_range;
 357                         stm.line += stm.line_base + (opcode % stm.line_range);
 358
 359                         if (check_line (&stm, offset, &location))
 360                                 goto out_success;
 361                 }
 362         }
 363
 364  error_out:
 365         mono_debugger_unlock ();
 366         return NULL;
 367
 368  out_success:
 369         mono_debugger_unlock ();
 370         return location;
 371 }
 372
 373 static void
 374 add_line (StatementMachine *stm, GPtrArray *il_offset_array, GPtrArray *line_number_array)
 375 {
 376         if (stm->line > 0) {
 377                 g_ptr_array_add (il_offset_array, GUINT_TO_POINTER (stm->offset));
 378                 g_ptr_array_add (line_number_array, GUINT_TO_POINTER (stm->line));
 379         }
 380
 381         if (!stm->is_hidden && !stm->first_file)
 382                 stm->first_file = stm->file;
 383 }
 384
 385 /*
 386  * mono_debug_symfile_free_location:
 387  *
 388  *   Free a MonoDebugSourceLocation returned by
 389  *   mono_debug_symfile_lookup_location
 390  */
 391 void
 392 mono_debug_symfile_free_location   (MonoDebugSourceLocation  *location)
 393 {
 394         g_free (location->source_file);
 395         g_free (location);
 396 }
 397
 398 /*
 399  * mono_debug_symfile_get_line_numbers:
 400  *
 401  *   All the output parameters can be NULL.
 402  */
 403 void
 404 mono_debug_symfile_get_line_numbers (MonoDebugMethodInfo *minfo, char **source_file, int *n_il_offsets, int **il_offsets, int **line_numbers)
 405 {
 406         // FIXME: Unify this with mono_debug_symfile_lookup_location
 407         MonoSymbolFile *symfile;
 408         const unsigned char *ptr;
 409         StatementMachine stm;
 410         guint32 i;
 411         GPtrArray *il_offset_array, *line_number_array;
 412
 413         if (source_file)
 414                 *source_file = NULL;
 415         if (n_il_offsets)
 416                 *n_il_offsets = 0;
 417
 418         if ((symfile = minfo->handle->symfile) == NULL)
 419                 return;
 420
 421         il_offset_array = g_ptr_array_new ();
 422         line_number_array = g_ptr_array_new ();
 423
 424         stm.line_base = read32 (&symfile->offset_table->_line_number_table_line_base);
 425         stm.line_range = read32 (&symfile->offset_table->_line_number_table_line_range);
 426         stm.opcode_base = (guint8) read32 (&symfile->offset_table->_line_number_table_opcode_base);
 427         stm.max_address_incr = (255 - stm.opcode_base) / stm.line_range;
 428
 429         mono_debugger_lock ();
 430
 431         ptr = symfile->raw_contents + minfo->lnt_offset;
 432
 433         stm.symfile = symfile;
 434         stm.offset = stm.last_offset = 0;
 435         stm.last_file = 0;
 436         stm.last_line = 0;
 437         stm.first_file = 0;
 438         stm.file = 1;
 439         stm.line = 1;
 440         stm.is_hidden = FALSE;
 441
 442         while (TRUE) {
 443                 guint8 opcode = *ptr++;
 444
 445                 if (opcode == 0) {
 446                         guint8 size = *ptr++;
 447                         const unsigned char *end_ptr = ptr + size;
 448
 449                         opcode = *ptr++;
 450
 451                         if (opcode == DW_LNE_end_sequence) {
 452                                 add_line (&stm, il_offset_array, line_number_array);
 453                                 break;
 454                         } else if (opcode == DW_LNE_MONO_negate_is_hidden) {
 455                                 stm.is_hidden = !stm.is_hidden;
 456                         } else if ((opcode >= DW_LNE_MONO__extensions_start) &&
 457                                    (opcode <= DW_LNE_MONO__extensions_end)) {
 458                                 ; // reserved for future extensions
 459                         } else {
 460                                 g_warning ("Unknown extended opcode %x in LNT", opcode);
 461                         }
 462
 463                         ptr = end_ptr;
 464                         continue;
 465                 } else if (opcode < stm.opcode_base) {
 466                         switch (opcode) {
 467                         case DW_LNS_copy:
 468                                 add_line (&stm, il_offset_array, line_number_array);
 469                                 break;
 470                         case DW_LNS_advance_pc:
 471                                 stm.offset += read_leb128 (ptr, &ptr);
 472                                 break;
 473                         case DW_LNS_advance_line:
 474                                 stm.line += read_leb128 (ptr, &ptr);
 475                                 break;
 476                         case DW_LNS_set_file:
 477                                 stm.file = read_leb128 (ptr, &ptr);
 478                                 break;
 479                         case DW_LNS_const_add_pc:
 480                                 stm.offset += stm.max_address_incr;
 481                                 break;
 482                         default:
 483                                 g_warning ("Unknown standard opcode %x in LNT", opcode);
 484                                 g_assert_not_reached ();
 485                         }
 486                 } else {
 487                         opcode -= stm.opcode_base;
 488
 489                         stm.offset += opcode / stm.line_range;
 490                         stm.line += stm.line_base + (opcode % stm.line_range);
 491
 492                         add_line (&stm, il_offset_array, line_number_array);
 493                 }
 494         }
 495
 496         if (!stm.file && stm.first_file)
 497                 stm.file = stm.first_file;
 498
 499         if (stm.file) {
 500                 int offset = read32(&(stm.symfile->offset_table->_source_table_offset)) +
 501                         (stm.file - 1) * sizeof (MonoSymbolFileSourceEntry);
 502                 MonoSymbolFileSourceEntry *se = (MonoSymbolFileSourceEntry *)
 503                         (stm.symfile->raw_contents + offset);
 504
 505                 if (source_file)
 506                         *source_file = read_string (stm.symfile->raw_contents + read32(&(se->_data_offset)));
 507         }
 508
 509         if (n_il_offsets)
 510                 *n_il_offsets = il_offset_array->len;
 511         if (il_offsets && line_numbers) {
 512                 *il_offsets = g_malloc (il_offset_array->len * sizeof (int));
 513                 *line_numbers = g_malloc (il_offset_array->len * sizeof (int));
 514                 for (i = 0; i < il_offset_array->len; ++i) {
 515                         (*il_offsets) [i] = GPOINTER_TO_UINT (g_ptr_array_index (il_offset_array, i));
 516                         (*line_numbers) [i] = GPOINTER_TO_UINT (g_ptr_array_index (line_number_array, i));
 517                 }
 518         }
 519         g_ptr_array_free (il_offset_array, TRUE);
 520         g_ptr_array_free (line_number_array, TRUE);
 521
 522         mono_debugger_unlock ();
 523         return;
 524 }
 525
 526 gint32
 527 _mono_debug_address_from_il_offset (MonoDebugMethodJitInfo *jit, guint32 il_offset)
 528 {
 529         int i;
 530
 531         if (!jit || !jit->line_numbers)
 532                 return -1;
 533
 534         for (i = jit->num_line_numbers - 1; i >= 0; i--) {
 535                 MonoDebugLineNumberEntry lne = jit->line_numbers [i];
 536
 537                 if (lne.il_offset < 0)
 538                         continue;
 539                 if (lne.il_offset <= il_offset)
 540                         return lne.native_offset;
 541         }
 542
 543         return 0;
 544 }
 545
 546 static int
 547 compare_method (const void *key, const void *object)
 548 {
 549         guint32 token = GPOINTER_TO_UINT (key);
 550         MonoSymbolFileMethodEntry *me = (MonoSymbolFileMethodEntry*)object;
 551
 552         return token - read32(&(me->_token));
 553 }
 554
 555 MonoDebugMethodInfo *
 556 mono_debug_symfile_lookup_method (MonoDebugHandle *handle, MonoMethod *method)
 557 {
 558         MonoSymbolFileMethodEntry *first_ie, *ie;
 559         MonoDebugMethodInfo *minfo;
 560         MonoSymbolFile *symfile = handle->symfile;
 561
 562         if (!symfile->method_hash)
 563                 return NULL;
 564
 565         if (handle->image != mono_class_get_image (mono_method_get_class (method)))
 566                 return NULL;
 567
 568         mono_debugger_lock ();
 569
 570         minfo = g_hash_table_lookup (symfile->method_hash, method);
 571         if (minfo) {
 572                 mono_debugger_unlock ();
 573                 return minfo;
 574         }
 575
 576         first_ie = (MonoSymbolFileMethodEntry *)
 577                 (symfile->raw_contents + read32(&(symfile->offset_table->_method_table_offset)));
 578
 579         ie = bsearch (GUINT_TO_POINTER (mono_method_get_token (method)), first_ie,
 580                                    read32(&(symfile->offset_table->_method_count)),
 581                                    sizeof (MonoSymbolFileMethodEntry), compare_method);
 582
 583         if (!ie) {
 584                 mono_debugger_unlock ();
 585                 return NULL;
 586         }
 587
 588         minfo = g_new0 (MonoDebugMethodInfo, 1);
 589         minfo->index = (ie - first_ie) + 1;
 590         minfo->method = method;
 591         minfo->handle = handle;
 592
 593         minfo->data_offset = read32 (&(ie->_data_offset));
 594         minfo->lnt_offset = read32 (&(ie->_line_number_table));
 595
 596         g_hash_table_insert (symfile->method_hash, method, minfo);
 597
 598         mono_debugger_unlock ();
 599         return minfo;
 600 }
 601
 602 /*
 603  * mono_debug_symfile_lookup_locals:
 604  *
 605  *   Return information about the local variables of MINFO from the symbol file.
 606  * Return NULL if no information can be found.
 607  * The result should be freed using mono_debug_symfile_free_locals ().
 608  */
 609 MonoDebugLocalsInfo*
 610 mono_debug_symfile_lookup_locals (MonoDebugMethodInfo *minfo)
 611 {
 612         MonoSymbolFile *symfile = minfo->handle->symfile;
 613         const guint8 *p;
 614         int i, len, compile_unit_index, locals_offset, num_locals, block_index;
 615         int namespace_id, code_block_table_offset;
 616         MonoDebugLocalsInfo *res;
 617
 618         if (!symfile)
 619                 return NULL;
 620
 621         p = symfile->raw_contents + minfo->data_offset;
 622
 623         compile_unit_index = read_leb128 (p, &p);
 624         locals_offset = read_leb128 (p, &p);
 625         namespace_id = read_leb128 (p, &p);
 626         code_block_table_offset = read_leb128 (p, &p);
 627
 628         res = g_new0 (MonoDebugLocalsInfo, 1);
 629
 630         p = symfile->raw_contents + code_block_table_offset;
 631         res->num_blocks = read_leb128 (p, &p);
 632         res->code_blocks = g_new0 (MonoDebugCodeBlock, res->num_blocks);
 633         for (i = 0; i < res->num_blocks; ++i) {
 634                 res->code_blocks [i].type = read_leb128 (p, &p);
 635                 res->code_blocks [i].parent = read_leb128 (p, &p);
 636                 res->code_blocks [i].start_offset = read_leb128 (p, &p);
 637                 res->code_blocks [i].end_offset = read_leb128 (p, &p);
 638         }
 639
 640         p = symfile->raw_contents + locals_offset;
 641         num_locals = read_leb128 (p, &p);
 642
 643         res->num_locals = num_locals;
 644         res->locals = g_new0 (MonoDebugLocalVar, num_locals);
 645
 646         for (i = 0; i < num_locals; ++i) {
 647                 res->locals [i].index = read_leb128 (p, &p);
 648                 len = read_leb128 (p, &p);
 649                 res->locals [i].name = g_malloc (len + 1);
 650                 memcpy (res->locals [i].name, p, len);
 651                 res->locals [i].name [len] = '\0';
 652                 p += len;
 653                 block_index = read_leb128 (p, &p);
 654                 if (block_index >= 1 && block_index <= res->num_blocks)
 655                         res->locals [i].block = &res->code_blocks [block_index - 1];
 656         }
 657
 658         return res;
 659 }
 660
 661 /*
 662  * mono_debug_symfile_free_locals:
 663  *
 664  *   Free all the data allocated by mono_debug_symfile_lookup_locals ().
 665  */
 666 void
 667 mono_debug_symfile_free_locals (MonoDebugLocalsInfo *info)
 668 {
 669         int i;
 670
 671         for (i = 0; i < info->num_locals; ++i)
 672                 g_free (info->locals [i].name);
 673         g_free (info->locals);
 674         g_free (info->code_blocks);
 675         g_free (info);
 676 }