wimlib.net Git - wimlib/blob - src/wim.c

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