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   1 /*
   2  * wim.c - Stuff that doesn't fit into any other file
   3  */
   4
   5 /*
   6  * Copyright (C) 2012, 2013 Eric Biggers
   7  *
   8  * This file is part of wimlib, a library for working with WIM files.
   9  *
  10  * wimlib is free software; you can redistribute it and/or modify it under the
  11  * terms of the GNU General Public License as published by the Free
  12  * Software Foundation; either version 3 of the License, or (at your option)
  13  * any later version.
  14  *
  15  * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY
  16  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
  17  * A PARTICULAR PURPOSE. See the GNU General Public License for more
  18  * details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with wimlib; if not, see http://www.gnu.org/licenses/.
  22  */
  23
  24 #ifdef HAVE_CONFIG_H
  25 #  include "config.h"
  26 #endif
  27
  28 #include "wimlib/error.h"
  29 #include "wimlib/dentry.h"
  30 #include "wimlib/encoding.h"
  31 #include "wimlib/file_io.h"
  32 #include "wimlib/integrity.h"
  33 #include "wimlib/lookup_table.h"
  34 #include "wimlib/metadata.h"
  35 #ifdef WITH_NTFS_3G
  36 #  include "wimlib/ntfs_3g.h" /* for do_ntfs_umount() */
  37 #endif
  38 #include "wimlib/security.h"
  39 #include "wimlib/wim.h"
  40 #include "wimlib/xml.h"
  41 #include "wimlib/compressor_ops.h"
  42 #include "wimlib/decompressor_ops.h"
  43
  44 #ifdef __WIN32__
  45 #  include "wimlib/win32.h" /* for realpath() replacement */
  46 #endif
  47
  48 #include <errno.h>
  49 #include <fcntl.h>
  50 #ifndef __WIN32__
  51 #  include <langinfo.h>
  52 #endif
  53 #include <limits.h>
  54 #include <stdarg.h>
  55 #include <stdlib.h>
  56 #include <unistd.h>
  57
  58 static int
  59 image_print_metadata(WIMStruct *wim)
  60 {
  61         DEBUG("Printing metadata for image %d", wim->current_image);
  62         print_wim_security_data(wim_security_data(wim));
  63         return for_dentry_in_tree(wim_root_dentry(wim), print_dentry,
  64                                   wim->lookup_table);
  65 }
  66
  67
  68 static WIMStruct *
  69 new_wim_struct(void)
  70 {
  71         WIMStruct *wim = CALLOC(1, sizeof(WIMStruct));
  72         if (wim) {
  73                 wim->in_fd.fd = -1;
  74                 wim->out_fd.fd = -1;
  75                 INIT_LIST_HEAD(&wim->subwims);
  76         }
  77         return wim;
  78 }
  79
  80 /* Determine if the chunk size is valid for the specified compression type.  */
  81 static bool
  82 wim_chunk_size_valid(u32 chunk_size, int ctype)
  83 {
  84         u32 order;
  85
  86         /* Chunk size is meaningless for uncompressed WIMs --- any value is
  87          * okay.  */
  88         if (ctype == WIMLIB_COMPRESSION_TYPE_NONE)
  89                 return true;
  90
  91         /* Chunk size must be power of 2.  */
  92         if (chunk_size == 0)
  93                 return false;
  94         order = bsr32(chunk_size);
  95         if (chunk_size != 1U << order)
  96                 return false;
  97
  98         /* Order        Size
  99          * =====        ====
 100          * 15           32768
 101          * 16           65536
 102          * 17           131072
 103          * 18           262144
 104          * 19           524288
 105          * 20           1048576
 106          * 21           2097152
 107          * 22           4194304
 108          * 23           8388608
 109          * 24           16777216
 110          * 25           33554432
 111          * 26           67108864
 112          */
 113         switch (ctype) {
 114         case WIMLIB_COMPRESSION_TYPE_LZX:
 115                 /* For LZX compression, the chunk size corresponds to the LZX
 116                  * window size, which according the LZX specification can be any
 117                  * power of 2 between 2^15 and 2^21, inclusively.  All these are
 118                  * supported by wimlib; however, unfortunately only 2^15 is
 119                  * supported by WIMGAPI[1] so this value is used by default.
 120                  *
 121                  * [1] WIMGAPI (Windows 7) attempts to decompress LZX chunk
 122                  * sizes > 2^15 but seems to have bug(s) that cause it to fail
 123                  * or crash.  (I tried several tweaks to the LZX data but none
 124                  * resulted in successful decompression.)  WIMGAPI (Windows 8)
 125                  * appears to refuse to open WIMs with chunk size > 2^15
 126                  * entirely.  */
 127                 return order >= 15 && order <= 21;
 128
 129         case WIMLIB_COMPRESSION_TYPE_XPRESS:
 130                 /* WIMGAPI (Windows 7) didn't seem to support XPRESS chunk size
 131                  * below 32768 bytes, but larger power-of-two sizes appear to be
 132                  * supported.  67108864 was the largest size that worked.
 133                  * (Note, however, that the offsets of XPRESS matches are still
 134                  * limited to 65535 bytes even when a much larger chunk size is
 135                  * used!)
 136                  *
 137                  * WIMGAPI (Windows 8) seemed to have removed the support for
 138                  * larger XPRESS chunk sizes and will refuse to open such WIMs.
 139                  *
 140                  * 2^15 = 32768 is the default value used for compatibility, but
 141                  * wimlib can actually use up to 2^26.  */
 142                 return order >= 15 && order <= 26;
 143
 144         case WIMLIB_COMPRESSION_TYPE_LZMS:
 145                 return order >= 15 && order <= 26;
 146         }
 147         return false;
 148 }
 149
 150 /* Return the default chunk size to use for the specified compression type.
 151  *
 152  * See notes above in wim_chunk_size_valid().  */
 153 static u32
 154 wim_default_chunk_size(int ctype)
 155 {
 156         switch (ctype) {
 157         case WIMLIB_COMPRESSION_TYPE_LZMS:
 158                 return 131072;
 159         default:
 160                 return 32768;
 161         }
 162 }
 163
 164 /*
 165  * Calls a function on images in the WIM.  If @image is WIMLIB_ALL_IMAGES, @visitor
 166  * is called on the WIM once for each image, with each image selected as the
 167  * current image in turn.  If @image is a certain image, @visitor is called on
 168  * the WIM only once, with that image selected.
 169  */
 170 int
 171 for_image(WIMStruct *wim, int image, int (*visitor)(WIMStruct *))
 172 {
 173         int ret;
 174         int start;
 175         int end;
 176         int i;
 177
 178         if (image == WIMLIB_ALL_IMAGES) {
 179                 start = 1;
 180                 end = wim->hdr.image_count;
 181         } else if (image >= 1 && image <= wim->hdr.image_count) {
 182                 start = image;
 183                 end = image;
 184         } else {
 185                 return WIMLIB_ERR_INVALID_IMAGE;
 186         }
 187         for (i = start; i <= end; i++) {
 188                 ret = select_wim_image(wim, i);
 189                 if (ret != 0)
 190                         return ret;
 191                 ret = visitor(wim);
 192                 if (ret != 0)
 193                         return ret;
 194         }
 195         return 0;
 196 }
 197
 198 /* API function documented in wimlib.h  */
 199 WIMLIBAPI int
 200 wimlib_create_new_wim(int ctype, WIMStruct **wim_ret)
 201 {
 202         WIMStruct *wim;
 203         struct wim_lookup_table *table;
 204         int ret;
 205
 206         wimlib_global_init(WIMLIB_INIT_FLAG_ASSUME_UTF8);
 207
 208         DEBUG("Creating new WIM with %"TS" compression.",
 209               wimlib_get_compression_type_string(ctype));
 210
 211         /* Allocate the WIMStruct. */
 212         wim = new_wim_struct();
 213         if (wim == NULL)
 214                 return WIMLIB_ERR_NOMEM;
 215
 216         ret = init_wim_header(&wim->hdr, ctype, wim_default_chunk_size(ctype));
 217         if (ret)
 218                 goto out_free;
 219
 220         table = new_lookup_table(9001);
 221         if (table == NULL) {
 222                 ret = WIMLIB_ERR_NOMEM;
 223                 goto out_free;
 224         }
 225         wim->lookup_table = table;
 226         wim->refcnts_ok = 1;
 227         wim->compression_type = ctype;
 228         wim->out_compression_type = ctype;
 229         wim->chunk_size = wim->hdr.chunk_size;
 230         wim->out_chunk_size = wim->hdr.chunk_size;
 231         *wim_ret = wim;
 232         return 0;
 233 out_free:
 234         FREE(wim);
 235         return ret;
 236 }
 237
 238 int
 239 select_wim_image(WIMStruct *wim, int image)
 240 {
 241         struct wim_image_metadata *imd;
 242         int ret;
 243
 244         DEBUG("Selecting image %d", image);
 245
 246         if (image == WIMLIB_NO_IMAGE) {
 247                 ERROR("Invalid image: %d", WIMLIB_NO_IMAGE);
 248                 return WIMLIB_ERR_INVALID_IMAGE;
 249         }
 250
 251         if (image == wim->current_image)
 252                 return 0;
 253
 254         if (image < 1 || image > wim->hdr.image_count) {
 255                 ERROR("Cannot select image %d: There are only %u images",
 256                       image, wim->hdr.image_count);
 257                 return WIMLIB_ERR_INVALID_IMAGE;
 258         }
 259
 260         if (!wim_has_metadata(wim)) {
 261                 ERROR("\"%"TS"\" does not contain metadata resources!", wim->filename);
 262                 if (wim->hdr.part_number != 1)
 263                         ERROR("Specify the first part of the split WIM instead.");
 264                 return WIMLIB_ERR_METADATA_NOT_FOUND;
 265         }
 266
 267         /* If a valid image is currently selected, it can be freed if it is not
 268          * modified.  */
 269         if (wim->current_image != WIMLIB_NO_IMAGE) {
 270                 imd = wim_get_current_image_metadata(wim);
 271                 if (!imd->modified) {
 272                         wimlib_assert(list_empty(&imd->unhashed_streams));
 273                         DEBUG("Freeing image %u", wim->current_image);
 274                         destroy_image_metadata(imd, NULL, false);
 275                 }
 276         }
 277         wim->current_image = image;
 278         imd = wim_get_current_image_metadata(wim);
 279         if (imd->root_dentry || imd->modified) {
 280                 ret = 0;
 281         } else {
 282                 #ifdef ENABLE_DEBUG
 283                 DEBUG("Reading metadata resource specified by the following "
 284                       "lookup table entry:");
 285                 print_lookup_table_entry(imd->metadata_lte, stderr);
 286                 #endif
 287                 ret = read_metadata_resource(wim, imd);
 288                 if (ret)
 289                         wim->current_image = WIMLIB_NO_IMAGE;
 290         }
 291         return ret;
 292 }
 293
 294
 295 /* API function documented in wimlib.h  */
 296 WIMLIBAPI const tchar *
 297 wimlib_get_compression_type_string(int ctype)
 298 {
 299         switch (ctype) {
 300                 case WIMLIB_COMPRESSION_TYPE_NONE:
 301                         return T("None");
 302                 case WIMLIB_COMPRESSION_TYPE_LZX:
 303                         return T("LZX");
 304                 case WIMLIB_COMPRESSION_TYPE_XPRESS:
 305                         return T("XPRESS");
 306                 case WIMLIB_COMPRESSION_TYPE_LZMS:
 307                         return T("LZMS");
 308                 default:
 309                         return T("Invalid");
 310         }
 311 }
 312
 313 /* API function documented in wimlib.h  */
 314 WIMLIBAPI int
 315 wimlib_resolve_image(WIMStruct *wim, const tchar *image_name_or_num)
 316 {
 317         tchar *p;
 318         long image;
 319         int i;
 320
 321         if (!image_name_or_num || !*image_name_or_num)
 322                 return WIMLIB_NO_IMAGE;
 323
 324         if (!tstrcasecmp(image_name_or_num, T("all"))
 325             || !tstrcasecmp(image_name_or_num, T("*")))
 326                 return WIMLIB_ALL_IMAGES;
 327         image = tstrtol(image_name_or_num, &p, 10);
 328         if (p != image_name_or_num && *p == T('\0') && image > 0) {
 329                 if (image > wim->hdr.image_count)
 330                         return WIMLIB_NO_IMAGE;
 331                 return image;
 332         } else {
 333                 for (i = 1; i <= wim->hdr.image_count; i++) {
 334                         if (!tstrcmp(image_name_or_num,
 335                                      wimlib_get_image_name(wim, i)))
 336                                 return i;
 337                 }
 338                 return WIMLIB_NO_IMAGE;
 339         }
 340 }
 341
 342 /* API function documented in wimlib.h  */
 343 WIMLIBAPI void
 344 wimlib_print_available_images(const WIMStruct *wim, int image)
 345 {
 346         int first;
 347         int last;
 348         int i;
 349         int n;
 350         if (image == WIMLIB_ALL_IMAGES) {
 351                 n = tprintf(T("Available Images:\n"));
 352                 first = 1;
 353                 last = wim->hdr.image_count;
 354         } else if (image >= 1 && image <= wim->hdr.image_count) {
 355                 n = tprintf(T("Information for Image %d\n"), image);
 356                 first = image;
 357                 last = image;
 358         } else {
 359                 tprintf(T("wimlib_print_available_images(): Invalid image %d"),
 360                         image);
 361                 return;
 362         }
 363         for (i = 0; i < n - 1; i++)
 364                 tputchar(T('-'));
 365         tputchar(T('\n'));
 366         for (i = first; i <= last; i++)
 367                 print_image_info(wim->wim_info, i);
 368 }
 369
 370
 371 /* API function documented in wimlib.h  */
 372 WIMLIBAPI int
 373 wimlib_print_metadata(WIMStruct *wim, int image)
 374 {
 375         return for_image(wim, image, image_print_metadata);
 376 }
 377
 378 /* API function documented in wimlib.h  */
 379 WIMLIBAPI int
 380 wimlib_get_wim_info(WIMStruct *wim, struct wimlib_wim_info *info)
 381 {
 382         memset(info, 0, sizeof(struct wimlib_wim_info));
 383         memcpy(info->guid, wim->hdr.guid, WIMLIB_GUID_LEN);
 384         info->image_count = wim->hdr.image_count;
 385         info->boot_index = wim->hdr.boot_idx;
 386         info->wim_version = wim->hdr.wim_version;
 387         info->chunk_size = wim->hdr.chunk_size;
 388         info->part_number = wim->hdr.part_number;
 389         info->total_parts = wim->hdr.total_parts;
 390         info->compression_type = wim->compression_type;
 391         info->total_bytes = wim_info_get_total_bytes(wim->wim_info);
 392         info->has_integrity_table = wim_has_integrity_table(wim);
 393         info->opened_from_file = (wim->filename != NULL);
 394         info->is_readonly = (wim->hdr.flags & WIM_HDR_FLAG_READONLY) ||
 395                              (wim->hdr.total_parts != 1) ||
 396                              (wim->filename && taccess(wim->filename, W_OK));
 397         info->has_rpfix = (wim->hdr.flags & WIM_HDR_FLAG_RP_FIX) != 0;
 398         info->is_marked_readonly = (wim->hdr.flags & WIM_HDR_FLAG_READONLY) != 0;
 399         info->write_in_progress = (wim->hdr.flags & WIM_HDR_FLAG_WRITE_IN_PROGRESS) != 0;
 400         info->metadata_only = (wim->hdr.flags & WIM_HDR_FLAG_METADATA_ONLY) != 0;
 401         info->resource_only = (wim->hdr.flags & WIM_HDR_FLAG_RESOURCE_ONLY) != 0;
 402         info->spanned = (wim->hdr.flags & WIM_HDR_FLAG_SPANNED) != 0;
 403         info->pipable = wim_is_pipable(wim);
 404         return 0;
 405 }
 406
 407 /* API function documented in wimlib.h  */
 408 WIMLIBAPI int
 409 wimlib_set_wim_info(WIMStruct *wim, const struct wimlib_wim_info *info, int which)
 410 {
 411         int ret;
 412
 413         if (which & WIMLIB_CHANGE_READONLY_FLAG) {
 414                 if (info->is_marked_readonly)
 415                         wim->hdr.flags |= WIM_HDR_FLAG_READONLY;
 416                 else
 417                         wim->hdr.flags &= ~WIM_HDR_FLAG_READONLY;
 418         }
 419
 420         if ((which & ~WIMLIB_CHANGE_READONLY_FLAG) == 0)
 421                 return 0;
 422
 423         ret = can_modify_wim(wim);
 424         if (ret)
 425                 return ret;
 426
 427         if (which & WIMLIB_CHANGE_GUID) {
 428                 memcpy(wim->hdr.guid, info->guid, WIM_GID_LEN);
 429                 wim->guid_set_explicitly = 1;
 430         }
 431
 432         if (which & WIMLIB_CHANGE_BOOT_INDEX) {
 433                 if (info->boot_index > wim->hdr.image_count) {
 434                         ERROR("%u is not 0 or a valid image in the WIM to mark as bootable",
 435                               info->boot_index);
 436                         return WIMLIB_ERR_INVALID_IMAGE;
 437                 }
 438                 wim->hdr.boot_idx = info->boot_index;
 439         }
 440
 441         if (which & WIMLIB_CHANGE_RPFIX_FLAG) {
 442                 if (info->has_rpfix)
 443                         wim->hdr.flags |= WIM_HDR_FLAG_RP_FIX;
 444                 else
 445                         wim->hdr.flags &= ~WIM_HDR_FLAG_RP_FIX;
 446         }
 447         return 0;
 448 }
 449
 450 /* API function documented in wimlib.h  */
 451 WIMLIBAPI int
 452 wimlib_set_output_compression_type(WIMStruct *wim, int ctype)
 453 {
 454         switch (ctype) {
 455         case WIMLIB_COMPRESSION_TYPE_INVALID:
 456                 break;
 457         case WIMLIB_COMPRESSION_TYPE_NONE:
 458         case WIMLIB_COMPRESSION_TYPE_LZX:
 459         case WIMLIB_COMPRESSION_TYPE_XPRESS:
 460         case WIMLIB_COMPRESSION_TYPE_LZMS:
 461                 wim->out_compression_type = ctype;
 462
 463                 /* Reset the chunk size if it's no longer valid.  */
 464                 if (!wim_chunk_size_valid(wim->out_chunk_size,
 465                                           wim->out_compression_type))
 466                         wim->out_chunk_size = wim_default_chunk_size(wim->out_compression_type);
 467                 return 0;
 468         }
 469         return WIMLIB_ERR_INVALID_PARAM;
 470 }
 471
 472 /* API function documented in wimlib.h  */
 473 WIMLIBAPI int
 474 wimlib_set_output_chunk_size(WIMStruct *wim, uint32_t chunk_size)
 475 {
 476         if (!wim_chunk_size_valid(chunk_size, wim->out_compression_type)) {
 477                 ERROR("Invalid chunk size (%"PRIu32" bytes) "
 478                       "for compression type %"TS"!",
 479                       chunk_size,
 480                       wimlib_get_compression_type_string(wim->out_compression_type));
 481                 switch (wim->out_compression_type) {
 482                 case WIMLIB_COMPRESSION_TYPE_XPRESS:
 483                         ERROR("Valid chunk sizes for XPRESS are "
 484                               "32768, 65536, 131072, ..., 67108864.");
 485                         break;
 486                 case WIMLIB_COMPRESSION_TYPE_LZX:
 487                         ERROR("Valid chunk sizes for LZX are "
 488                               "32768, 65536, 131072, ..., 2097152.");
 489                         break;
 490                 case WIMLIB_COMPRESSION_TYPE_LZMS:
 491                         ERROR("Valid chunk sizes for LZMS are "
 492                               "32768, 65536, 131072, ..., 67108864.");
 493                         break;
 494                 }
 495                 return WIMLIB_ERR_INVALID_CHUNK_SIZE;
 496         }
 497         if (chunk_size != 32768 &&
 498             wim->out_compression_type != WIMLIB_COMPRESSION_TYPE_LZMS)
 499         {
 500                 WARNING  ("Changing the compression chunk size to any value other than\n"
 501                 "          the default of 32768 bytes eliminates compatibility with\n"
 502                 "          Microsoft's software!");
 503         }
 504         wim->out_chunk_size = chunk_size;
 505         return 0;
 506 }
 507
 508 static int
 509 do_open_wim(const tchar *filename, struct filedes *fd_ret)
 510 {
 511         int raw_fd;
 512
 513         raw_fd = topen(filename, O_RDONLY | O_BINARY);
 514         if (raw_fd < 0) {
 515                 ERROR_WITH_ERRNO("Can't open \"%"TS"\" read-only", filename);
 516                 return WIMLIB_ERR_OPEN;
 517         }
 518         filedes_init(fd_ret, raw_fd);
 519         return 0;
 520 }
 521
 522 int
 523 reopen_wim(WIMStruct *wim)
 524 {
 525         wimlib_assert(!filedes_valid(&wim->in_fd));
 526         return do_open_wim(wim->filename, &wim->in_fd);
 527 }
 528
 529 int
 530 close_wim(WIMStruct *wim)
 531 {
 532         if (filedes_valid(&wim->in_fd)) {
 533                 filedes_close(&wim->in_fd);
 534                 filedes_invalidate(&wim->in_fd);
 535         }
 536         return 0;
 537 }
 538
 539 /*
 540  * Begins the reading of a WIM file; opens the file and reads its header and
 541  * lookup table, and optionally checks the integrity.
 542  */
 543 static int
 544 begin_read(WIMStruct *wim, const void *wim_filename_or_fd,
 545            int open_flags, wimlib_progress_func_t progress_func)
 546 {
 547         int ret;
 548         int xml_num_images;
 549         const tchar *wimfile;
 550
 551         if (open_flags & WIMLIB_OPEN_FLAG_FROM_PIPE) {
 552                 wimfile = NULL;
 553                 filedes_init(&wim->in_fd, *(const int*)wim_filename_or_fd);
 554                 wim->in_fd.is_pipe = 1;
 555         } else {
 556                 wimfile = wim_filename_or_fd;
 557                 ret = do_open_wim(wimfile, &wim->in_fd);
 558                 if (ret)
 559                         return ret;
 560
 561                 /* The absolute path to the WIM is requested so that
 562                  * wimlib_overwrite() still works even if the process changes
 563                  * its working directory.  This actually happens if a WIM is
 564                  * mounted read-write, since the FUSE thread changes directory
 565                  * to "/", and it needs to be able to find the WIM file again.
 566                  *
 567                  * This will break if the full path to the WIM changes in the
 568                  * intervening time...
 569                  *
 570                  * Warning: in Windows native builds, realpath() calls the
 571                  * replacement function in win32_replacements.c.
 572                  */
 573                 wim->filename = realpath(wimfile, NULL);
 574                 if (wim->filename == NULL) {
 575                         ERROR_WITH_ERRNO("Failed to resolve WIM filename");
 576                         if (errno == ENOMEM)
 577                                 return WIMLIB_ERR_NOMEM;
 578                         else
 579                                 return WIMLIB_ERR_OPEN;
 580                 }
 581         }
 582
 583         ret = read_wim_header(wim, &wim->hdr);
 584         if (ret)
 585                 return ret;
 586
 587         if (wim->hdr.flags & WIM_HDR_FLAG_WRITE_IN_PROGRESS) {
 588                 WARNING("The WIM_HDR_FLAG_WRITE_IN_PROGRESS flag is set in the header of\n"
 589                         "          \"%"TS"\".  It may be being changed by another process,\n"
 590                         "          or a process may have crashed while writing the WIM.",
 591                         wimfile);
 592         }
 593
 594         if (open_flags & WIMLIB_OPEN_FLAG_WRITE_ACCESS) {
 595                 ret = can_modify_wim(wim);
 596                 if (ret)
 597                         return ret;
 598         }
 599
 600         if ((open_flags & WIMLIB_OPEN_FLAG_ERROR_IF_SPLIT) &&
 601             (wim->hdr.total_parts != 1))
 602                 return WIMLIB_ERR_IS_SPLIT_WIM;
 603
 604         DEBUG("According to header, WIM contains %u images", wim->hdr.image_count);
 605
 606         /* If the boot index is invalid, print a warning and set it to 0 */
 607         if (wim->hdr.boot_idx > wim->hdr.image_count) {
 608                 WARNING("In `%"TS"', image %u is marked as bootable, "
 609                         "but there are only %u images in the WIM",
 610                         wimfile, wim->hdr.boot_idx, wim->hdr.image_count);
 611                 wim->hdr.boot_idx = 0;
 612         }
 613
 614         /* Check and cache the compression type */
 615         if (wim->hdr.flags & WIM_HDR_FLAG_COMPRESSION) {
 616                 if (wim->hdr.flags & WIM_HDR_FLAG_COMPRESS_LZX) {
 617                         wim->compression_type = WIMLIB_COMPRESSION_TYPE_LZX;
 618                 } else if (wim->hdr.flags & WIM_HDR_FLAG_COMPRESS_XPRESS) {
 619                         wim->compression_type = WIMLIB_COMPRESSION_TYPE_XPRESS;
 620                 } else if (wim->hdr.flags & WIM_HDR_FLAG_COMPRESS_LZMS) {
 621                         wim->compression_type = WIMLIB_COMPRESSION_TYPE_LZMS;
 622                 } else {
 623                         ERROR("The compression flag is set on \"%"TS"\", but "
 624                               "a flag for a recognized format is not",
 625                               wimfile);
 626                         return WIMLIB_ERR_INVALID_COMPRESSION_TYPE;
 627                 }
 628         } else {
 629                 wim->compression_type = WIMLIB_COMPRESSION_TYPE_NONE;
 630         }
 631         wim->out_compression_type = wim->compression_type;
 632
 633         /* Check and cache the chunk size.  */
 634         wim->chunk_size = wim->out_chunk_size = wim->hdr.chunk_size;
 635         if (!wim_chunk_size_valid(wim->chunk_size, wim->compression_type)) {
 636                 ERROR("Invalid chunk size (%"PRIu32" bytes) "
 637                       "for compression type %"TS"!",
 638                       wim->chunk_size,
 639                       wimlib_get_compression_type_string(wim->compression_type));
 640                 return WIMLIB_ERR_INVALID_CHUNK_SIZE;
 641         }
 642
 643         if (open_flags & WIMLIB_OPEN_FLAG_CHECK_INTEGRITY) {
 644                 ret = check_wim_integrity(wim, progress_func);
 645                 if (ret == WIM_INTEGRITY_NONEXISTENT) {
 646                         WARNING("No integrity information for `%"TS"'; skipping "
 647                                 "integrity check.", wimfile);
 648                 } else if (ret == WIM_INTEGRITY_NOT_OK) {
 649                         ERROR("WIM is not intact! (Failed integrity check)");
 650                         return WIMLIB_ERR_INTEGRITY;
 651                 } else if (ret != WIM_INTEGRITY_OK) {
 652                         return ret;
 653                 }
 654         }
 655
 656         if (wim->hdr.image_count != 0 && wim->hdr.part_number == 1) {
 657                 wim->image_metadata = new_image_metadata_array(wim->hdr.image_count);
 658                 if (wim->image_metadata == NULL)
 659                         return WIMLIB_ERR_NOMEM;
 660         }
 661
 662         if (open_flags & WIMLIB_OPEN_FLAG_FROM_PIPE) {
 663                 wim->lookup_table = new_lookup_table(9001);
 664                 if (wim->lookup_table == NULL)
 665                         return WIMLIB_ERR_NOMEM;
 666         } else {
 667                 ret = read_wim_lookup_table(wim);
 668                 if (ret)
 669                         return ret;
 670
 671                 ret = read_wim_xml_data(wim);
 672                 if (ret)
 673                         return ret;
 674
 675                 xml_num_images = wim_info_get_num_images(wim->wim_info);
 676                 if (xml_num_images != wim->hdr.image_count) {
 677                         ERROR("In the file `%"TS"', there are %u <IMAGE> elements "
 678                               "in the XML data,", wimfile, xml_num_images);
 679                         ERROR("but %u images in the WIM!  There must be exactly one "
 680                               "<IMAGE> element per image.", wim->hdr.image_count);
 681                         return WIMLIB_ERR_IMAGE_COUNT;
 682                 }
 683                 DEBUG("Done beginning read of WIM file `%"TS"'.", wimfile);
 684         }
 685         return 0;
 686 }
 687
 688 int
 689 open_wim_as_WIMStruct(const void *wim_filename_or_fd, int open_flags,
 690                       WIMStruct **wim_ret, wimlib_progress_func_t progress_func)
 691 {
 692         WIMStruct *wim;
 693         int ret;
 694
 695         if (open_flags & WIMLIB_OPEN_FLAG_FROM_PIPE)
 696                 DEBUG("Opening pipable WIM from file descriptor %d.", *(const int*)wim_filename_or_fd);
 697         else
 698                 DEBUG("Opening WIM file \"%"TS"\"", (const tchar*)wim_filename_or_fd);
 699
 700         wimlib_global_init(WIMLIB_INIT_FLAG_ASSUME_UTF8);
 701
 702         if (wim_ret == NULL)
 703                 return WIMLIB_ERR_INVALID_PARAM;
 704
 705         wim = new_wim_struct();
 706         if (wim == NULL)
 707                 return WIMLIB_ERR_NOMEM;
 708
 709         ret = begin_read(wim, wim_filename_or_fd, open_flags, progress_func);
 710         if (ret) {
 711                 wimlib_free(wim);
 712                 return ret;
 713         }
 714
 715         DEBUG("Successfully opened WIM and created WIMStruct.");
 716         *wim_ret = wim;
 717         return 0;
 718 }
 719
 720 /* API function documented in wimlib.h  */
 721 WIMLIBAPI int
 722 wimlib_open_wim(const tchar *wimfile, int open_flags,
 723                 WIMStruct **wim_ret, wimlib_progress_func_t progress_func)
 724 {
 725         open_flags &= WIMLIB_OPEN_MASK_PUBLIC;
 726         return open_wim_as_WIMStruct(wimfile, open_flags, wim_ret,
 727                                      progress_func);
 728 }
 729
 730 void
 731 destroy_image_metadata(struct wim_image_metadata *imd,
 732                        struct wim_lookup_table *table,
 733                        bool free_metadata_lte)
 734 {
 735         free_dentry_tree(imd->root_dentry, table);
 736         imd->root_dentry = NULL;
 737         free_wim_security_data(imd->security_data);
 738         imd->security_data = NULL;
 739
 740         if (free_metadata_lte) {
 741                 free_lookup_table_entry(imd->metadata_lte);
 742                 imd->metadata_lte = NULL;
 743         }
 744         if (table == NULL) {
 745                 struct wim_lookup_table_entry *lte, *tmp;
 746                 list_for_each_entry_safe(lte, tmp, &imd->unhashed_streams, unhashed_list)
 747                         free_lookup_table_entry(lte);
 748         }
 749         INIT_LIST_HEAD(&imd->unhashed_streams);
 750         INIT_LIST_HEAD(&imd->inode_list);
 751 #ifdef WITH_NTFS_3G
 752         if (imd->ntfs_vol) {
 753                 do_ntfs_umount(imd->ntfs_vol);
 754                 imd->ntfs_vol = NULL;
 755         }
 756 #endif
 757 }
 758
 759 void
 760 put_image_metadata(struct wim_image_metadata *imd,
 761                    struct wim_lookup_table *table)
 762 {
 763         if (imd && --imd->refcnt == 0) {
 764                 destroy_image_metadata(imd, table, true);
 765                 FREE(imd);
 766         }
 767 }
 768
 769 /* Appends the specified image metadata structure to the array of image metadata
 770  * for a WIM, and increments the image count. */
 771 int
 772 append_image_metadata(WIMStruct *wim, struct wim_image_metadata *imd)
 773 {
 774         struct wim_image_metadata **imd_array;
 775
 776         DEBUG("Reallocating image metadata array for image_count = %u",
 777               wim->hdr.image_count + 1);
 778         imd_array = REALLOC(wim->image_metadata,
 779                             sizeof(wim->image_metadata[0]) * (wim->hdr.image_count + 1));
 780
 781         if (imd_array == NULL)
 782                 return WIMLIB_ERR_NOMEM;
 783         wim->image_metadata = imd_array;
 784         imd_array[wim->hdr.image_count++] = imd;
 785         return 0;
 786 }
 787
 788
 789 struct wim_image_metadata *
 790 new_image_metadata(void)
 791 {
 792         struct wim_image_metadata *imd;
 793
 794         imd = CALLOC(1, sizeof(*imd));
 795         if (imd) {
 796                 imd->refcnt = 1;
 797                 INIT_LIST_HEAD(&imd->inode_list);
 798                 INIT_LIST_HEAD(&imd->unhashed_streams);
 799                 DEBUG("Created new image metadata (refcnt=1)");
 800         } else {
 801                 ERROR_WITH_ERRNO("Failed to allocate new image metadata structure");
 802         }
 803         return imd;
 804 }
 805
 806 struct wim_image_metadata **
 807 new_image_metadata_array(unsigned num_images)
 808 {
 809         struct wim_image_metadata **imd_array;
 810
 811         DEBUG("Creating new image metadata array for %u images",
 812               num_images);
 813
 814         imd_array = CALLOC(num_images, sizeof(imd_array[0]));
 815
 816         if (imd_array == NULL) {
 817                 ERROR("Failed to allocate memory for %u image metadata structures",
 818                       num_images);
 819                 return NULL;
 820         }
 821         for (unsigned i = 0; i < num_images; i++) {
 822                 imd_array[i] = new_image_metadata();
 823                 if (imd_array[i] == NULL) {
 824                         for (unsigned j = 0; j < i; j++)
 825                                 put_image_metadata(imd_array[j], NULL);
 826                         FREE(imd_array);
 827                         return NULL;
 828                 }
 829         }
 830         return imd_array;
 831 }
 832
 833 /* Checksum all streams that are unhashed (other than the metadata streams),
 834  * merging them into the lookup table as needed.  This is a no-op unless the
 835  * library has previously used to add or mount an image using the same
 836  * WIMStruct. */
 837 int
 838 wim_checksum_unhashed_streams(WIMStruct *wim)
 839 {
 840         int ret;
 841
 842         if (!wim_has_metadata(wim))
 843                 return 0;
 844         for (int i = 0; i < wim->hdr.image_count; i++) {
 845                 struct wim_lookup_table_entry *lte, *tmp;
 846                 struct wim_image_metadata *imd = wim->image_metadata[i];
 847                 image_for_each_unhashed_stream_safe(lte, tmp, imd) {
 848                         struct wim_lookup_table_entry *new_lte;
 849                         ret = hash_unhashed_stream(lte, wim->lookup_table, &new_lte);
 850                         if (ret)
 851                                 return ret;
 852                         if (new_lte != lte)
 853                                 free_lookup_table_entry(lte);
 854                 }
 855         }
 856         return 0;
 857 }
 858
 859 /*
 860  * can_modify_wim - Check if a given WIM is writeable.  This is only the case if
 861  * it meets the following three conditions:
 862  *
 863  * 1. Write access is allowed to the underlying file (if any) at the filesystem level.
 864  * 2. The WIM is not part of a spanned set.
 865  * 3. The WIM_HDR_FLAG_READONLY flag is not set in the WIM header.
 866  *
 867  * Return value is 0 if writable; WIMLIB_ERR_WIM_IS_READONLY otherwise.
 868  */
 869 int
 870 can_modify_wim(WIMStruct *wim)
 871 {
 872         if (wim->filename) {
 873                 if (taccess(wim->filename, W_OK)) {
 874                         ERROR_WITH_ERRNO("Can't modify \"%"TS"\"", wim->filename);
 875                         return WIMLIB_ERR_WIM_IS_READONLY;
 876                 }
 877         }
 878         if (wim->hdr.total_parts != 1) {
 879                 ERROR("Cannot modify \"%"TS"\": is part of a split WIM",
 880                       wim->filename);
 881                 return WIMLIB_ERR_WIM_IS_READONLY;
 882         }
 883         if (wim->hdr.flags & WIM_HDR_FLAG_READONLY) {
 884                 ERROR("Cannot modify \"%"TS"\": is marked read-only",
 885                       wim->filename);
 886                 return WIMLIB_ERR_WIM_IS_READONLY;
 887         }
 888         return 0;
 889 }
 890
 891 /*
 892  * can_delete_from_wim - Check if files or images can be deleted from a given
 893  * WIM file.
 894  *
 895  * This theoretically should be exactly the same as can_modify_wim(), but
 896  * unfortunately, due to bugs in Microsoft's software that generate incorrect
 897  * reference counts for some WIM resources, we need to run expensive
 898  * verifications to make sure the reference counts are correct on all WIM
 899  * resources.  Otherwise we might delete a WIM resource whose reference count
 900  * has fallen to 0, but is actually still referenced somewhere.
 901  */
 902 int
 903 can_delete_from_wim(WIMStruct *wim)
 904 {
 905         int ret;
 906
 907         ret = can_modify_wim(wim);
 908         if (ret)
 909                 return ret;
 910         if (!wim->refcnts_ok) {
 911                 ret = wim_recalculate_refcnts(wim);
 912                 if (ret)
 913                         return ret;
 914         }
 915         return 0;
 916 }
 917
 918 /* API function documented in wimlib.h  */
 919 WIMLIBAPI void
 920 wimlib_free(WIMStruct *wim)
 921 {
 922         if (wim == NULL)
 923                 return;
 924
 925         DEBUG("Freeing WIMStruct (filename=\"%"TS"\", image_count=%u)",
 926               wim->filename, wim->hdr.image_count);
 927
 928         while (!list_empty(&wim->subwims)) {
 929                 WIMStruct *subwim;
 930
 931                 subwim = list_entry(wim->subwims.next, WIMStruct, subwim_node);
 932                 list_del(&subwim->subwim_node);
 933                 DEBUG("Freeing subwim.");
 934                 wimlib_free(subwim);
 935         }
 936
 937         if (filedes_valid(&wim->in_fd))
 938                 filedes_close(&wim->in_fd);
 939         if (filedes_valid(&wim->out_fd))
 940                 filedes_close(&wim->out_fd);
 941
 942         free_lookup_table(wim->lookup_table);
 943
 944         wimlib_free_decompressor(wim->decompressor);
 945
 946         FREE(wim->filename);
 947         free_wim_info(wim->wim_info);
 948         if (wim->image_metadata) {
 949                 for (unsigned i = 0; i < wim->hdr.image_count; i++)
 950                         put_image_metadata(wim->image_metadata[i], NULL);
 951                 FREE(wim->image_metadata);
 952         }
 953         FREE(wim);
 954 }
 955
 956 static bool
 957 test_locale_ctype_utf8(void)
 958 {
 959 #ifdef __WIN32__
 960         return false;
 961 #else
 962         char *ctype = nl_langinfo(CODESET);
 963
 964         return (!strstr(ctype, "UTF-8") ||
 965                 !strstr(ctype, "UTF8") ||
 966                 !strstr(ctype, "utf8") ||
 967                 !strstr(ctype, "utf-8"));
 968 #endif
 969 }
 970
 971 /* API function documented in wimlib.h  */
 972 WIMLIBAPI int
 973 wimlib_global_init(int init_flags)
 974 {
 975         static bool already_inited = false;
 976         int ret;
 977
 978         if (already_inited)
 979                 return 0;
 980         libxml_global_init();
 981         if (!(init_flags & WIMLIB_INIT_FLAG_ASSUME_UTF8)) {
 982                 wimlib_mbs_is_utf8 = test_locale_ctype_utf8();
 983         #ifdef WITH_NTFS_3G
 984                 if (!wimlib_mbs_is_utf8)
 985                         libntfs3g_global_init();
 986         #endif
 987         }
 988 #ifdef __WIN32__
 989         ret = win32_global_init(init_flags);
 990         if (ret)
 991                 return ret;
 992 #else
 993         ret = 0;
 994 #endif
 995         already_inited = true;
 996         return ret;
 997 }
 998
 999 /* API function documented in wimlib.h  */
1000 WIMLIBAPI void
1001 wimlib_global_cleanup(void)
1002 {
1003         libxml_global_cleanup();
1004         iconv_global_cleanup();
1005 #ifdef __WIN32__
1006         win32_global_cleanup();
1007 #endif
1008         cleanup_decompressor_params();
1009         cleanup_compressor_params();
1010 }