| 1 | /* Definitions for BFD wrappers used by GDB. |
| 2 | |
| 3 | Copyright (C) 2011, 2012 |
| 4 | 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 "gdb_bfd.h" |
| 23 | #include "gdb_assert.h" |
| 24 | #include "gdb_string.h" |
| 25 | #include "hashtab.h" |
| 26 | #ifdef HAVE_ZLIB_H |
| 27 | #include <zlib.h> |
| 28 | #endif |
| 29 | #ifdef HAVE_MMAP |
| 30 | #include <sys/mman.h> |
| 31 | #ifndef MAP_FAILED |
| 32 | #define MAP_FAILED ((void *) -1) |
| 33 | #endif |
| 34 | #endif |
| 35 | |
| 36 | /* An object of this type is stored in the section's user data when |
| 37 | mapping a section. */ |
| 38 | |
| 39 | struct gdb_bfd_section_data |
| 40 | { |
| 41 | /* Size of the data. */ |
| 42 | bfd_size_type size; |
| 43 | /* If the data was mmapped, this is the length of the map. */ |
| 44 | bfd_size_type map_len; |
| 45 | /* The data. If NULL, the section data has not been read. */ |
| 46 | void *data; |
| 47 | /* If the data was mmapped, this is the map address. */ |
| 48 | void *map_addr; |
| 49 | }; |
| 50 | |
| 51 | /* See gdb_bfd.h. */ |
| 52 | |
| 53 | void |
| 54 | gdb_bfd_stash_filename (struct bfd *abfd) |
| 55 | { |
| 56 | char *name = bfd_get_filename (abfd); |
| 57 | char *data; |
| 58 | |
| 59 | data = bfd_alloc (abfd, strlen (name) + 1); |
| 60 | strcpy (data, name); |
| 61 | |
| 62 | /* Unwarranted chumminess with BFD. */ |
| 63 | abfd->filename = data; |
| 64 | } |
| 65 | |
| 66 | /* An object of this type is stored in each BFD's user data. */ |
| 67 | |
| 68 | struct gdb_bfd_data |
| 69 | { |
| 70 | /* The reference count. */ |
| 71 | int refc; |
| 72 | |
| 73 | /* The mtime of the BFD at the point the cache entry was made. */ |
| 74 | time_t mtime; |
| 75 | }; |
| 76 | |
| 77 | /* A hash table storing all the BFDs maintained in the cache. */ |
| 78 | |
| 79 | static htab_t gdb_bfd_cache; |
| 80 | |
| 81 | /* The type of an object being looked up in gdb_bfd_cache. We use |
| 82 | htab's capability of storing one kind of object (BFD in this case) |
| 83 | and using a different sort of object for searching. */ |
| 84 | |
| 85 | struct gdb_bfd_cache_search |
| 86 | { |
| 87 | /* The filename. */ |
| 88 | const char *filename; |
| 89 | /* The mtime. */ |
| 90 | time_t mtime; |
| 91 | }; |
| 92 | |
| 93 | /* A hash function for BFDs. */ |
| 94 | |
| 95 | static hashval_t |
| 96 | hash_bfd (const void *b) |
| 97 | { |
| 98 | const bfd *abfd = b; |
| 99 | |
| 100 | /* It is simplest to just hash the filename. */ |
| 101 | return htab_hash_string (bfd_get_filename (abfd)); |
| 102 | } |
| 103 | |
| 104 | /* An equality function for BFDs. Note that this expects the caller |
| 105 | to search using struct gdb_bfd_cache_search only, not BFDs. */ |
| 106 | |
| 107 | static int |
| 108 | eq_bfd (const void *a, const void *b) |
| 109 | { |
| 110 | const bfd *abfd = a; |
| 111 | const struct gdb_bfd_cache_search *s = b; |
| 112 | struct gdb_bfd_data *gdata = bfd_usrdata (abfd); |
| 113 | |
| 114 | return (gdata->mtime == s->mtime |
| 115 | && strcmp (bfd_get_filename (abfd), s->filename) == 0); |
| 116 | } |
| 117 | |
| 118 | /* See gdb_bfd.h. */ |
| 119 | |
| 120 | struct bfd * |
| 121 | gdb_bfd_open (const char *name, const char *target, int fd) |
| 122 | { |
| 123 | hashval_t hash; |
| 124 | void **slot; |
| 125 | bfd *abfd; |
| 126 | struct gdb_bfd_cache_search search; |
| 127 | struct stat st; |
| 128 | |
| 129 | if (gdb_bfd_cache == NULL) |
| 130 | gdb_bfd_cache = htab_create_alloc (1, hash_bfd, eq_bfd, NULL, |
| 131 | xcalloc, xfree); |
| 132 | |
| 133 | if (fd == -1) |
| 134 | { |
| 135 | fd = open (name, O_RDONLY | O_BINARY); |
| 136 | if (fd == -1) |
| 137 | { |
| 138 | bfd_set_error (bfd_error_system_call); |
| 139 | return NULL; |
| 140 | } |
| 141 | } |
| 142 | |
| 143 | search.filename = name; |
| 144 | if (fstat (fd, &st) < 0) |
| 145 | { |
| 146 | /* Weird situation here. */ |
| 147 | search.mtime = 0; |
| 148 | } |
| 149 | else |
| 150 | search.mtime = st.st_mtime; |
| 151 | |
| 152 | /* Note that this must compute the same result as hash_bfd. */ |
| 153 | hash = htab_hash_string (name); |
| 154 | /* Note that we cannot use htab_find_slot_with_hash here, because |
| 155 | opening the BFD may fail; and this would violate hashtab |
| 156 | invariants. */ |
| 157 | abfd = htab_find_with_hash (gdb_bfd_cache, &search, hash); |
| 158 | if (abfd != NULL) |
| 159 | { |
| 160 | close (fd); |
| 161 | gdb_bfd_ref (abfd); |
| 162 | return abfd; |
| 163 | } |
| 164 | |
| 165 | abfd = bfd_fopen (name, target, FOPEN_RB, fd); |
| 166 | if (abfd == NULL) |
| 167 | return NULL; |
| 168 | |
| 169 | slot = htab_find_slot_with_hash (gdb_bfd_cache, &search, hash, INSERT); |
| 170 | gdb_assert (!*slot); |
| 171 | *slot = abfd; |
| 172 | |
| 173 | gdb_bfd_stash_filename (abfd); |
| 174 | gdb_bfd_ref (abfd); |
| 175 | return abfd; |
| 176 | } |
| 177 | |
| 178 | /* A helper function that releases any section data attached to the |
| 179 | BFD. */ |
| 180 | |
| 181 | static void |
| 182 | free_one_bfd_section (bfd *abfd, asection *sectp, void *ignore) |
| 183 | { |
| 184 | struct gdb_bfd_section_data *sect = bfd_get_section_userdata (abfd, sectp); |
| 185 | |
| 186 | if (sect != NULL && sect->data != NULL) |
| 187 | { |
| 188 | #ifdef HAVE_MMAP |
| 189 | if (sect->map_addr != NULL) |
| 190 | { |
| 191 | int res; |
| 192 | |
| 193 | res = munmap (sect->map_addr, sect->map_len); |
| 194 | gdb_assert (res == 0); |
| 195 | } |
| 196 | else |
| 197 | #endif |
| 198 | xfree (sect->data); |
| 199 | } |
| 200 | } |
| 201 | |
| 202 | /* Close ABFD, and warn if that fails. */ |
| 203 | |
| 204 | static int |
| 205 | gdb_bfd_close_or_warn (struct bfd *abfd) |
| 206 | { |
| 207 | int ret; |
| 208 | char *name = bfd_get_filename (abfd); |
| 209 | |
| 210 | bfd_map_over_sections (abfd, free_one_bfd_section, NULL); |
| 211 | |
| 212 | ret = bfd_close (abfd); |
| 213 | |
| 214 | if (!ret) |
| 215 | warning (_("cannot close \"%s\": %s"), |
| 216 | name, bfd_errmsg (bfd_get_error ())); |
| 217 | |
| 218 | return ret; |
| 219 | } |
| 220 | |
| 221 | /* See gdb_bfd.h. */ |
| 222 | |
| 223 | void |
| 224 | gdb_bfd_ref (struct bfd *abfd) |
| 225 | { |
| 226 | struct gdb_bfd_data *gdata; |
| 227 | |
| 228 | if (abfd == NULL) |
| 229 | return; |
| 230 | |
| 231 | gdata = bfd_usrdata (abfd); |
| 232 | |
| 233 | if (gdata != NULL) |
| 234 | { |
| 235 | gdata->refc += 1; |
| 236 | return; |
| 237 | } |
| 238 | |
| 239 | gdata = bfd_zalloc (abfd, sizeof (struct gdb_bfd_data)); |
| 240 | gdata->refc = 1; |
| 241 | gdata->mtime = bfd_get_mtime (abfd); |
| 242 | bfd_usrdata (abfd) = gdata; |
| 243 | } |
| 244 | |
| 245 | /* See gdb_bfd.h. */ |
| 246 | |
| 247 | void |
| 248 | gdb_bfd_unref (struct bfd *abfd) |
| 249 | { |
| 250 | struct gdb_bfd_data *gdata; |
| 251 | struct gdb_bfd_cache_search search; |
| 252 | |
| 253 | if (abfd == NULL) |
| 254 | return; |
| 255 | |
| 256 | gdata = bfd_usrdata (abfd); |
| 257 | gdb_assert (gdata->refc >= 1); |
| 258 | |
| 259 | gdata->refc -= 1; |
| 260 | if (gdata->refc > 0) |
| 261 | return; |
| 262 | |
| 263 | search.filename = bfd_get_filename (abfd); |
| 264 | |
| 265 | if (gdb_bfd_cache && search.filename) |
| 266 | { |
| 267 | hashval_t hash = htab_hash_string (search.filename); |
| 268 | void **slot; |
| 269 | |
| 270 | search.mtime = gdata->mtime; |
| 271 | slot = htab_find_slot_with_hash (gdb_bfd_cache, &search, hash, |
| 272 | NO_INSERT); |
| 273 | |
| 274 | if (slot && *slot) |
| 275 | htab_clear_slot (gdb_bfd_cache, slot); |
| 276 | } |
| 277 | |
| 278 | bfd_usrdata (abfd) = NULL; /* Paranoia. */ |
| 279 | |
| 280 | gdb_bfd_close_or_warn (abfd); |
| 281 | } |
| 282 | |
| 283 | /* A helper function that returns the section data descriptor |
| 284 | associated with SECTION. If no such descriptor exists, a new one |
| 285 | is allocated and cleared. */ |
| 286 | |
| 287 | static struct gdb_bfd_section_data * |
| 288 | get_section_descriptor (asection *section) |
| 289 | { |
| 290 | struct gdb_bfd_section_data *result; |
| 291 | |
| 292 | result = bfd_get_section_userdata (section->owner, section); |
| 293 | |
| 294 | if (result == NULL) |
| 295 | { |
| 296 | result = bfd_zalloc (section->owner, sizeof (*result)); |
| 297 | bfd_set_section_userdata (section->owner, section, result); |
| 298 | } |
| 299 | |
| 300 | return result; |
| 301 | } |
| 302 | |
| 303 | /* Decompress a section that was compressed using zlib. Store the |
| 304 | decompressed buffer, and its size, in DESCRIPTOR. */ |
| 305 | |
| 306 | static void |
| 307 | zlib_decompress_section (asection *sectp, |
| 308 | struct gdb_bfd_section_data *descriptor) |
| 309 | { |
| 310 | bfd *abfd = sectp->owner; |
| 311 | #ifndef HAVE_ZLIB_H |
| 312 | error (_("Support for zlib-compressed data (from '%s', section '%s') " |
| 313 | "is disabled in this copy of GDB"), |
| 314 | bfd_get_filename (abfd), |
| 315 | bfd_get_section_name (sectp)); |
| 316 | #else |
| 317 | bfd_size_type compressed_size = bfd_get_section_size (sectp); |
| 318 | gdb_byte *compressed_buffer = xmalloc (compressed_size); |
| 319 | struct cleanup *cleanup = make_cleanup (xfree, compressed_buffer); |
| 320 | struct cleanup *inner_cleanup; |
| 321 | bfd_size_type uncompressed_size; |
| 322 | gdb_byte *uncompressed_buffer; |
| 323 | z_stream strm; |
| 324 | int rc; |
| 325 | int header_size = 12; |
| 326 | struct dwarf2_per_bfd_section *section_data; |
| 327 | |
| 328 | if (bfd_seek (abfd, sectp->filepos, SEEK_SET) != 0 |
| 329 | || bfd_bread (compressed_buffer, |
| 330 | compressed_size, abfd) != compressed_size) |
| 331 | error (_("can't read data from '%s', section '%s'"), |
| 332 | bfd_get_filename (abfd), |
| 333 | bfd_get_section_name (abfd, sectp)); |
| 334 | |
| 335 | /* Read the zlib header. In this case, it should be "ZLIB" followed |
| 336 | by the uncompressed section size, 8 bytes in big-endian order. */ |
| 337 | if (compressed_size < header_size |
| 338 | || strncmp (compressed_buffer, "ZLIB", 4) != 0) |
| 339 | error (_("corrupt ZLIB header from '%s', section '%s'"), |
| 340 | bfd_get_filename (abfd), |
| 341 | bfd_get_section_name (abfd, sectp)); |
| 342 | uncompressed_size = compressed_buffer[4]; uncompressed_size <<= 8; |
| 343 | uncompressed_size += compressed_buffer[5]; uncompressed_size <<= 8; |
| 344 | uncompressed_size += compressed_buffer[6]; uncompressed_size <<= 8; |
| 345 | uncompressed_size += compressed_buffer[7]; uncompressed_size <<= 8; |
| 346 | uncompressed_size += compressed_buffer[8]; uncompressed_size <<= 8; |
| 347 | uncompressed_size += compressed_buffer[9]; uncompressed_size <<= 8; |
| 348 | uncompressed_size += compressed_buffer[10]; uncompressed_size <<= 8; |
| 349 | uncompressed_size += compressed_buffer[11]; |
| 350 | |
| 351 | /* It is possible the section consists of several compressed |
| 352 | buffers concatenated together, so we uncompress in a loop. */ |
| 353 | strm.zalloc = NULL; |
| 354 | strm.zfree = NULL; |
| 355 | strm.opaque = NULL; |
| 356 | strm.avail_in = compressed_size - header_size; |
| 357 | strm.next_in = (Bytef*) compressed_buffer + header_size; |
| 358 | strm.avail_out = uncompressed_size; |
| 359 | uncompressed_buffer = xmalloc (uncompressed_size); |
| 360 | inner_cleanup = make_cleanup (xfree, uncompressed_buffer); |
| 361 | rc = inflateInit (&strm); |
| 362 | while (strm.avail_in > 0) |
| 363 | { |
| 364 | if (rc != Z_OK) |
| 365 | error (_("setting up uncompression in '%s', section '%s': %d"), |
| 366 | bfd_get_filename (abfd), |
| 367 | bfd_get_section_name (abfd, sectp), |
| 368 | rc); |
| 369 | strm.next_out = ((Bytef*) uncompressed_buffer |
| 370 | + (uncompressed_size - strm.avail_out)); |
| 371 | rc = inflate (&strm, Z_FINISH); |
| 372 | if (rc != Z_STREAM_END) |
| 373 | error (_("zlib error uncompressing from '%s', section '%s': %d"), |
| 374 | bfd_get_filename (abfd), |
| 375 | bfd_get_section_name (abfd, sectp), |
| 376 | rc); |
| 377 | rc = inflateReset (&strm); |
| 378 | } |
| 379 | rc = inflateEnd (&strm); |
| 380 | if (rc != Z_OK |
| 381 | || strm.avail_out != 0) |
| 382 | error (_("concluding uncompression in '%s', section '%s': %d"), |
| 383 | bfd_get_filename (abfd), |
| 384 | bfd_get_section_name (abfd, sectp), |
| 385 | rc); |
| 386 | |
| 387 | discard_cleanups (inner_cleanup); |
| 388 | do_cleanups (cleanup); |
| 389 | |
| 390 | /* Attach the data to the BFD section. */ |
| 391 | descriptor->data = uncompressed_buffer; |
| 392 | descriptor->size = uncompressed_size; |
| 393 | #endif |
| 394 | } |
| 395 | |
| 396 | /* See gdb_bfd.h. */ |
| 397 | |
| 398 | const gdb_byte * |
| 399 | gdb_bfd_map_section (asection *sectp, bfd_size_type *size) |
| 400 | { |
| 401 | bfd *abfd; |
| 402 | gdb_byte *buf, *retbuf; |
| 403 | unsigned char header[4]; |
| 404 | struct gdb_bfd_section_data *descriptor; |
| 405 | |
| 406 | gdb_assert ((sectp->flags & SEC_RELOC) == 0); |
| 407 | gdb_assert (size != NULL); |
| 408 | |
| 409 | abfd = sectp->owner; |
| 410 | |
| 411 | descriptor = get_section_descriptor (sectp); |
| 412 | |
| 413 | /* If the data was already read for this BFD, just reuse it. */ |
| 414 | if (descriptor->data != NULL) |
| 415 | goto done; |
| 416 | |
| 417 | /* Check if the file has a 4-byte header indicating compression. */ |
| 418 | if (bfd_get_section_size (sectp) > sizeof (header) |
| 419 | && bfd_seek (abfd, sectp->filepos, SEEK_SET) == 0 |
| 420 | && bfd_bread (header, sizeof (header), abfd) == sizeof (header)) |
| 421 | { |
| 422 | /* Upon decompression, update the buffer and its size. */ |
| 423 | if (strncmp (header, "ZLIB", sizeof (header)) == 0) |
| 424 | { |
| 425 | zlib_decompress_section (sectp, descriptor); |
| 426 | goto done; |
| 427 | } |
| 428 | } |
| 429 | |
| 430 | #ifdef HAVE_MMAP |
| 431 | { |
| 432 | /* The page size, used when mmapping. */ |
| 433 | static int pagesize; |
| 434 | |
| 435 | if (pagesize == 0) |
| 436 | pagesize = getpagesize (); |
| 437 | |
| 438 | /* Only try to mmap sections which are large enough: we don't want |
| 439 | to waste space due to fragmentation. */ |
| 440 | |
| 441 | if (bfd_get_section_size (sectp) > 4 * pagesize) |
| 442 | { |
| 443 | descriptor->size = bfd_get_section_size (sectp); |
| 444 | descriptor->data = bfd_mmap (abfd, 0, descriptor->size, PROT_READ, |
| 445 | MAP_PRIVATE, sectp->filepos, |
| 446 | &descriptor->map_addr, |
| 447 | &descriptor->map_len); |
| 448 | |
| 449 | if ((caddr_t)descriptor->data != MAP_FAILED) |
| 450 | { |
| 451 | #if HAVE_POSIX_MADVISE |
| 452 | posix_madvise (descriptor->map_addr, descriptor->map_len, |
| 453 | POSIX_MADV_WILLNEED); |
| 454 | #endif |
| 455 | goto done; |
| 456 | } |
| 457 | |
| 458 | /* On failure, clear out the section data and try again. */ |
| 459 | memset (descriptor, 0, sizeof (*descriptor)); |
| 460 | } |
| 461 | } |
| 462 | #endif /* HAVE_MMAP */ |
| 463 | |
| 464 | /* If we get here, we are a normal, not-compressed section. */ |
| 465 | |
| 466 | descriptor->size = bfd_get_section_size (sectp); |
| 467 | descriptor->data = xmalloc (descriptor->size); |
| 468 | |
| 469 | if (bfd_seek (abfd, sectp->filepos, SEEK_SET) != 0 |
| 470 | || bfd_bread (descriptor->data, bfd_get_section_size (sectp), |
| 471 | abfd) != bfd_get_section_size (sectp)) |
| 472 | { |
| 473 | xfree (descriptor->data); |
| 474 | descriptor->data = NULL; |
| 475 | error (_("Can't read data for section '%s'"), |
| 476 | bfd_get_filename (abfd)); |
| 477 | } |
| 478 | |
| 479 | done: |
| 480 | gdb_assert (descriptor->data != NULL); |
| 481 | *size = descriptor->size; |
| 482 | return descriptor->data; |
| 483 | } |
| 484 | |
| 485 | \f |
| 486 | |
| 487 | /* See gdb_bfd.h. */ |
| 488 | |
| 489 | bfd * |
| 490 | gdb_bfd_fopen (const char *filename, const char *target, const char *mode, |
| 491 | int fd) |
| 492 | { |
| 493 | bfd *result = bfd_fopen (filename, target, mode, fd); |
| 494 | |
| 495 | if (result) |
| 496 | { |
| 497 | gdb_bfd_stash_filename (result); |
| 498 | gdb_bfd_ref (result); |
| 499 | } |
| 500 | |
| 501 | return result; |
| 502 | } |
| 503 | |
| 504 | /* See gdb_bfd.h. */ |
| 505 | |
| 506 | bfd * |
| 507 | gdb_bfd_openr (const char *filename, const char *target) |
| 508 | { |
| 509 | bfd *result = bfd_openr (filename, target); |
| 510 | |
| 511 | if (result) |
| 512 | { |
| 513 | gdb_bfd_stash_filename (result); |
| 514 | gdb_bfd_ref (result); |
| 515 | } |
| 516 | |
| 517 | return result; |
| 518 | } |
| 519 | |
| 520 | /* See gdb_bfd.h. */ |
| 521 | |
| 522 | bfd * |
| 523 | gdb_bfd_openw (const char *filename, const char *target) |
| 524 | { |
| 525 | bfd *result = bfd_openw (filename, target); |
| 526 | |
| 527 | if (result) |
| 528 | { |
| 529 | gdb_bfd_stash_filename (result); |
| 530 | gdb_bfd_ref (result); |
| 531 | } |
| 532 | |
| 533 | return result; |
| 534 | } |
| 535 | |
| 536 | /* See gdb_bfd.h. */ |
| 537 | |
| 538 | bfd * |
| 539 | gdb_bfd_openr_iovec (const char *filename, const char *target, |
| 540 | void *(*open_func) (struct bfd *nbfd, |
| 541 | void *open_closure), |
| 542 | void *open_closure, |
| 543 | file_ptr (*pread_func) (struct bfd *nbfd, |
| 544 | void *stream, |
| 545 | void *buf, |
| 546 | file_ptr nbytes, |
| 547 | file_ptr offset), |
| 548 | int (*close_func) (struct bfd *nbfd, |
| 549 | void *stream), |
| 550 | int (*stat_func) (struct bfd *abfd, |
| 551 | void *stream, |
| 552 | struct stat *sb)) |
| 553 | { |
| 554 | bfd *result = bfd_openr_iovec (filename, target, |
| 555 | open_func, open_closure, |
| 556 | pread_func, close_func, stat_func); |
| 557 | |
| 558 | if (result) |
| 559 | { |
| 560 | gdb_bfd_ref (result); |
| 561 | gdb_bfd_stash_filename (result); |
| 562 | } |
| 563 | |
| 564 | return result; |
| 565 | } |
| 566 | |
| 567 | /* See gdb_bfd.h. */ |
| 568 | |
| 569 | bfd * |
| 570 | gdb_bfd_openr_next_archived_file (bfd *archive, bfd *previous) |
| 571 | { |
| 572 | bfd *result = bfd_openr_next_archived_file (archive, previous); |
| 573 | |
| 574 | if (result) |
| 575 | { |
| 576 | gdb_bfd_ref (result); |
| 577 | /* No need to stash the filename here. */ |
| 578 | } |
| 579 | |
| 580 | return result; |
| 581 | } |
| 582 | |
| 583 | /* See gdb_bfd.h. */ |
| 584 | |
| 585 | bfd * |
| 586 | gdb_bfd_fdopenr (const char *filename, const char *target, int fd) |
| 587 | { |
| 588 | bfd *result = bfd_fdopenr (filename, target, fd); |
| 589 | |
| 590 | if (result) |
| 591 | { |
| 592 | gdb_bfd_ref (result); |
| 593 | gdb_bfd_stash_filename (result); |
| 594 | } |
| 595 | |
| 596 | return result; |
| 597 | } |