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