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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 *w)
  58 {
  59         DEBUG("Printing metadata for image %d", w->current_image);
  60         print_wim_security_data(wim_security_data(w));
  61         return for_dentry_in_tree(wim_root_dentry(w), print_dentry,
  62                                   w->lookup_table);
  63 }
  64
  65
  66 static int
  67 image_print_files(WIMStruct *w)
  68 {
  69         return for_dentry_in_tree(wim_root_dentry(w), print_dentry_full_path,
  70                                   NULL);
  71 }
  72
  73 static WIMStruct *
  74 new_wim_struct(void)
  75 {
  76         WIMStruct *w = CALLOC(1, sizeof(WIMStruct));
  77         if (w) {
  78                 w->in_fd = -1;
  79                 w->out_fd = -1;
  80         }
  81         return w;
  82 }
  83
  84 /*
  85  * Calls a function on images in the WIM.  If @image is WIMLIB_ALL_IMAGES, @visitor
  86  * is called on the WIM once for each image, with each image selected as the
  87  * current image in turn.  If @image is a certain image, @visitor is called on
  88  * the WIM only once, with that image selected.
  89  */
  90 int
  91 for_image(WIMStruct *w, int image, int (*visitor)(WIMStruct *))
  92 {
  93         int ret;
  94         int start;
  95         int end;
  96         int i;
  97
  98         if (image == WIMLIB_ALL_IMAGES) {
  99                 start = 1;
 100                 end = w->hdr.image_count;
 101         } else if (image >= 1 && image <= w->hdr.image_count) {
 102                 start = image;
 103                 end = image;
 104         } else {
 105                 return WIMLIB_ERR_INVALID_IMAGE;
 106         }
 107         for (i = start; i <= end; i++) {
 108                 ret = select_wim_image(w, i);
 109                 if (ret != 0)
 110                         return ret;
 111                 ret = visitor(w);
 112                 if (ret != 0)
 113                         return ret;
 114         }
 115         return 0;
 116 }
 117
 118 /*
 119  * Creates a WIMStruct for a new WIM file.
 120  */
 121 WIMLIBAPI int
 122 wimlib_create_new_wim(int ctype, WIMStruct **w_ret)
 123 {
 124         WIMStruct *w;
 125         struct wim_lookup_table *table;
 126         int ret;
 127
 128         wimlib_global_init(WIMLIB_INIT_FLAG_ASSUME_UTF8);
 129
 130         DEBUG("Creating new WIM with %"TS" compression.",
 131               wimlib_get_compression_type_string(ctype));
 132
 133         /* Allocate the WIMStruct. */
 134         w = new_wim_struct();
 135         if (!w)
 136                 return WIMLIB_ERR_NOMEM;
 137
 138         ret = init_header(&w->hdr, ctype);
 139         if (ret != 0)
 140                 goto out_free;
 141
 142         table = new_lookup_table(9001);
 143         if (!table) {
 144                 ret = WIMLIB_ERR_NOMEM;
 145                 goto out_free;
 146         }
 147         w->lookup_table = table;
 148         w->refcnts_ok = 1;
 149         w->compression_type = ctype;
 150         *w_ret = w;
 151         return 0;
 152 out_free:
 153         FREE(w);
 154         return ret;
 155 }
 156
 157 int
 158 select_wim_image(WIMStruct *w, int image)
 159 {
 160         struct wim_image_metadata *imd;
 161         int ret;
 162
 163         DEBUG("Selecting image %d", image);
 164
 165         if (image == WIMLIB_NO_IMAGE) {
 166                 ERROR("Invalid image: %d", WIMLIB_NO_IMAGE);
 167                 return WIMLIB_ERR_INVALID_IMAGE;
 168         }
 169
 170         if (image == w->current_image)
 171                 return 0;
 172
 173         if (image < 1 || image > w->hdr.image_count) {
 174                 ERROR("Cannot select image %d: There are only %u images",
 175                       image, w->hdr.image_count);
 176                 return WIMLIB_ERR_INVALID_IMAGE;
 177         }
 178
 179         /* If a valid image is currently selected, it can be freed if it is not
 180          * modified.  */
 181         if (w->current_image != WIMLIB_NO_IMAGE) {
 182                 imd = wim_get_current_image_metadata(w);
 183                 if (!imd->modified) {
 184                         wimlib_assert(list_empty(&imd->unhashed_streams));
 185                         DEBUG("Freeing image %u", w->current_image);
 186                         destroy_image_metadata(imd, NULL, false);
 187                 }
 188         }
 189         w->current_image = image;
 190         imd = wim_get_current_image_metadata(w);
 191         if (imd->root_dentry || imd->modified) {
 192                 ret = 0;
 193         } else {
 194                 #ifdef ENABLE_DEBUG
 195                 DEBUG("Reading metadata resource specified by the following "
 196                       "lookup table entry:");
 197                 print_lookup_table_entry(imd->metadata_lte, stderr);
 198                 #endif
 199                 ret = read_metadata_resource(w, imd);
 200                 if (ret)
 201                         w->current_image = WIMLIB_NO_IMAGE;
 202         }
 203         return ret;
 204 }
 205
 206
 207 WIMLIBAPI const tchar *
 208 wimlib_get_compression_type_string(int ctype)
 209 {
 210         switch (ctype) {
 211                 case WIMLIB_COMPRESSION_TYPE_NONE:
 212                         return T("None");
 213                 case WIMLIB_COMPRESSION_TYPE_LZX:
 214                         return T("LZX");
 215                 case WIMLIB_COMPRESSION_TYPE_XPRESS:
 216                         return T("XPRESS");
 217                 default:
 218                         return T("Invalid");
 219         }
 220 }
 221
 222 /*
 223  * Returns the number of an image in the WIM file, given a string that is either
 224  * the number of the image, or the name of the image.  The images are numbered
 225  * starting at 1.
 226  */
 227 WIMLIBAPI int
 228 wimlib_resolve_image(WIMStruct *w, const tchar *image_name_or_num)
 229 {
 230         tchar *p;
 231         long image;
 232         int i;
 233
 234         if (!image_name_or_num || !*image_name_or_num)
 235                 return WIMLIB_NO_IMAGE;
 236
 237         if (!tstrcasecmp(image_name_or_num, T("all"))
 238             || !tstrcasecmp(image_name_or_num, T("*")))
 239                 return WIMLIB_ALL_IMAGES;
 240         image = tstrtol(image_name_or_num, &p, 10);
 241         if (p != image_name_or_num && *p == T('\0') && image > 0) {
 242                 if (image > w->hdr.image_count)
 243                         return WIMLIB_NO_IMAGE;
 244                 return image;
 245         } else {
 246                 for (i = 1; i <= w->hdr.image_count; i++) {
 247                         if (!tstrcmp(image_name_or_num,
 248                                      wimlib_get_image_name(w, i)))
 249                                 return i;
 250                 }
 251                 return WIMLIB_NO_IMAGE;
 252         }
 253 }
 254
 255 /* Prints some basic information about a WIM file. */
 256 WIMLIBAPI void
 257 wimlib_print_wim_information(const WIMStruct *w)
 258 {
 259         const struct wim_header *hdr;
 260
 261         hdr = &w->hdr;
 262         tputs(T("WIM Information:"));
 263         tputs(T("----------------"));
 264         tprintf(T("Path:           %"TS"\n"), w->filename);
 265         tfputs(T("GUID:           0x"), stdout);
 266         print_byte_field(hdr->guid, WIM_GID_LEN, stdout);
 267         tputchar(T('\n'));
 268         tprintf(T("Image Count:    %d\n"), hdr->image_count);
 269         tprintf(T("Compression:    %"TS"\n"),
 270                 wimlib_get_compression_type_string(w->compression_type));
 271         tprintf(T("Part Number:    %d/%d\n"), hdr->part_number, hdr->total_parts);
 272         tprintf(T("Boot Index:     %d\n"), hdr->boot_idx);
 273         tprintf(T("Size:           %"PRIu64" bytes\n"),
 274                 wim_info_get_total_bytes(w->wim_info));
 275         tprintf(T("Integrity Info: %"TS"\n"),
 276                 (w->hdr.integrity.offset != 0) ? T("yes") : T("no"));
 277         tprintf(T("Relative path junction: %"TS"\n"),
 278                 (hdr->flags & WIM_HDR_FLAG_RP_FIX) ? T("yes") : T("no"));
 279         tputchar(T('\n'));
 280 }
 281
 282 WIMLIBAPI bool
 283 wimlib_has_integrity_table(const WIMStruct *w)
 284 {
 285         return w->hdr.integrity.size != 0;
 286 }
 287
 288 WIMLIBAPI void
 289 wimlib_print_available_images(const WIMStruct *w, int image)
 290 {
 291         int first;
 292         int last;
 293         int i;
 294         int n;
 295         if (image == WIMLIB_ALL_IMAGES) {
 296                 n = tprintf(T("Available Images:\n"));
 297                 first = 1;
 298                 last = w->hdr.image_count;
 299         } else if (image >= 1 && image <= w->hdr.image_count) {
 300                 n = tprintf(T("Information for Image %d\n"), image);
 301                 first = image;
 302                 last = image;
 303         } else {
 304                 tprintf(T("wimlib_print_available_images(): Invalid image %d"),
 305                         image);
 306                 return;
 307         }
 308         for (i = 0; i < n - 1; i++)
 309                 tputchar(T('-'));
 310         tputchar(T('\n'));
 311         for (i = first; i <= last; i++)
 312                 print_image_info(w->wim_info, i);
 313 }
 314
 315
 316 /* Prints the metadata for the specified image, which may be WIMLIB_ALL_IMAGES, but
 317  * not WIMLIB_NO_IMAGE. */
 318 WIMLIBAPI int
 319 wimlib_print_metadata(WIMStruct *w, int image)
 320 {
 321         if (w->hdr.part_number != 1) {
 322                 ERROR("Cannot show the metadata from part %hu of a %hu-part split WIM!",
 323                        w->hdr.part_number, w->hdr.total_parts);
 324                 ERROR("Select the first part of the split WIM to see the metadata.");
 325                 return WIMLIB_ERR_SPLIT_UNSUPPORTED;
 326         }
 327         return for_image(w, image, image_print_metadata);
 328 }
 329
 330 WIMLIBAPI int
 331 wimlib_print_files(WIMStruct *w, int image)
 332 {
 333         if (w->hdr.part_number != 1) {
 334                 ERROR("Cannot list the files from part %hu of a %hu-part split WIM!",
 335                        w->hdr.part_number, w->hdr.total_parts);
 336                 ERROR("Select the first part of the split WIM if you'd like to list the files.");
 337                 return WIMLIB_ERR_SPLIT_UNSUPPORTED;
 338         }
 339         return for_image(w, image, image_print_files);
 340 }
 341
 342 WIMLIBAPI int
 343 wimlib_get_wim_info(WIMStruct *wim, struct wimlib_wim_info *info)
 344 {
 345         memset(info, 0, sizeof(struct wimlib_wim_info));
 346         memcpy(info->guid, wim->hdr.guid, WIMLIB_GUID_LEN);
 347         info->image_count = wim->hdr.image_count;
 348         info->boot_index = wim->hdr.boot_idx;
 349         info->wim_version = WIM_VERSION;
 350         info->chunk_size = WIM_CHUNK_SIZE;
 351         info->part_number = wim->hdr.part_number;
 352         info->total_parts = wim->hdr.total_parts;
 353         info->compression_type = wim->compression_type;
 354         if (wim->wim_info)
 355                 info->total_bytes = wim->wim_info->total_bytes;
 356         else
 357                 info->total_bytes = 0;
 358         info->has_integrity_table = wim->hdr.integrity.offset != 0;
 359         info->opened_from_file = (wim->filename != NULL);
 360         info->is_readonly == (wim->hdr.flags & WIM_HDR_FLAG_READONLY) ||
 361                              (wim->hdr.total_parts != 1) ||
 362                              (wim->filename && taccess(wim->filename, W_OK));
 363         info->has_rpfix = (wim->hdr.flags & WIM_HDR_FLAG_RP_FIX) != 0;
 364         info->is_marked_readonly = (wim->hdr.flags & WIM_HDR_FLAG_READONLY) != 0;
 365         info->write_in_progress = (wim->hdr.flags & WIM_HDR_FLAG_WRITE_IN_PROGRESS) != 0;
 366         info->metadata_only = (wim->hdr.flags & WIM_HDR_FLAG_METADATA_ONLY) != 0;
 367         info->resource_only = (wim->hdr.flags & WIM_HDR_FLAG_RESOURCE_ONLY) != 0;
 368         info->spanned = (wim->hdr.flags & WIM_HDR_FLAG_SPANNED) != 0;
 369         return 0;
 370 }
 371
 372
 373 /* Deprecated */
 374 WIMLIBAPI int
 375 wimlib_get_boot_idx(const WIMStruct *wim)
 376 {
 377         struct wimlib_wim_info info;
 378
 379         wimlib_get_wim_info((WIMStruct*)wim, &info);
 380         return info.boot_index;
 381 }
 382
 383 /* Deprecated */
 384 WIMLIBAPI int
 385 wimlib_get_compression_type(const WIMStruct *wim)
 386 {
 387         struct wimlib_wim_info info;
 388
 389         wimlib_get_wim_info((WIMStruct*)wim, &info);
 390         return info.compression_type;
 391 }
 392
 393 /* Deprecated */
 394 WIMLIBAPI int
 395 wimlib_get_num_images(const WIMStruct *wim)
 396 {
 397         struct wimlib_wim_info info;
 398
 399         wimlib_get_wim_info((WIMStruct*)wim, &info);
 400         return info.image_count;
 401 }
 402
 403 /* Deprecated */
 404 WIMLIBAPI int
 405 wimlib_get_part_number(const WIMStruct *wim, int *total_parts_ret)
 406 {
 407         struct wimlib_wim_info info;
 408
 409         wimlib_get_wim_info((WIMStruct*)wim, &info);
 410         if (total_parts_ret)
 411                 *total_parts_ret = info.total_parts;
 412         return info.part_number;
 413 }
 414
 415 WIMLIBAPI int
 416 wimlib_set_wim_info(WIMStruct *wim, const struct wimlib_wim_info *info, int which)
 417 {
 418         int ret;
 419
 420         if (which & WIMLIB_CHANGE_READONLY_FLAG) {
 421                 if (info->is_marked_readonly)
 422                         wim->hdr.flags |= WIM_HDR_FLAG_READONLY;
 423                 else
 424                         wim->hdr.flags &= ~WIM_HDR_FLAG_READONLY;
 425         }
 426
 427         if ((which & ~WIMLIB_CHANGE_READONLY_FLAG) == 0)
 428                 return 0;
 429
 430         ret = can_modify_wim(wim);
 431         if (ret)
 432                 return ret;
 433
 434         if (which & WIMLIB_CHANGE_GUID)
 435                 memcpy(wim->hdr.guid, info->guid, WIM_GID_LEN);
 436
 437         if (which & WIMLIB_CHANGE_BOOT_INDEX) {
 438                 if (info->boot_index < 0 || info->boot_index > wim->hdr.image_count)
 439                 {
 440                         ERROR("%u is not 0 or a valid image in the WIM to mark as bootable",
 441                               info->boot_index);
 442                         return WIMLIB_ERR_INVALID_IMAGE;
 443                 }
 444                 wim->hdr.boot_idx = info->boot_index;
 445         }
 446
 447         if (which & WIMLIB_CHANGE_RPFIX_FLAG) {
 448                 if (info->has_rpfix)
 449                         wim->hdr.flags |= WIM_HDR_FLAG_RP_FIX;
 450                 else
 451                         wim->hdr.flags &= ~WIM_HDR_FLAG_RP_FIX;
 452         }
 453         return 0;
 454 }
 455
 456 /* Deprecated */
 457 WIMLIBAPI int
 458 wimlib_set_boot_idx(WIMStruct *wim, int boot_idx)
 459 {
 460         struct wimlib_wim_info info;
 461
 462         info.boot_index = boot_idx;
 463         return wimlib_set_wim_info(wim, &info, WIMLIB_CHANGE_BOOT_INDEX);
 464 }
 465
 466 static int
 467 do_open_wim(const tchar *filename, int *fd_ret)
 468 {
 469         int fd;
 470
 471         fd = topen(filename, O_RDONLY | O_BINARY);
 472         if (fd == -1) {
 473                 ERROR_WITH_ERRNO("Can't open \"%"TS"\" read-only", filename);
 474                 return WIMLIB_ERR_OPEN;
 475         }
 476         *fd_ret = fd;
 477         return 0;
 478 }
 479
 480 int
 481 reopen_wim(WIMStruct *w)
 482 {
 483         wimlib_assert(w->in_fd == -1);
 484         return do_open_wim(w->filename, &w->in_fd);
 485 }
 486
 487 int
 488 close_wim(WIMStruct *w)
 489 {
 490         if (w->in_fd != -1) {
 491                 close(w->in_fd);
 492                 w->in_fd = -1;
 493         }
 494         return 0;
 495 }
 496
 497 /*
 498  * Begins the reading of a WIM file; opens the file and reads its header and
 499  * lookup table, and optionally checks the integrity.
 500  */
 501 static int
 502 begin_read(WIMStruct *w, const tchar *in_wim_path, int open_flags,
 503            wimlib_progress_func_t progress_func)
 504 {
 505         int ret;
 506         int xml_num_images;
 507
 508         DEBUG("Reading the WIM file `%"TS"'", in_wim_path);
 509
 510         ret = do_open_wim(in_wim_path, &w->in_fd);
 511         if (ret)
 512                 return ret;
 513
 514         /* The absolute path to the WIM is requested so that wimlib_overwrite()
 515          * still works even if the process changes its working directory.  This
 516          * actually happens if a WIM is mounted read-write, since the FUSE
 517          * thread changes directory to "/", and it needs to be able to find the
 518          * WIM file again.
 519          *
 520          * This will break if the full path to the WIM changes in the
 521          * intervening time...
 522          *
 523          * Warning: in Windows native builds, realpath() calls the replacement
 524          * function in win32.c.
 525          */
 526         w->filename = realpath(in_wim_path, NULL);
 527         if (!w->filename) {
 528                 ERROR_WITH_ERRNO("Failed to resolve WIM filename");
 529                 if (errno == ENOMEM)
 530                         return WIMLIB_ERR_NOMEM;
 531                 else
 532                         return WIMLIB_ERR_OPEN;
 533         }
 534
 535         ret = read_header(w->filename, w->in_fd, &w->hdr);
 536         if (ret)
 537                 return ret;
 538
 539         if (w->hdr.flags & WIM_HDR_FLAG_WRITE_IN_PROGRESS) {
 540                 WARNING("The WIM_HDR_FLAG_WRITE_IN_PROGRESS is set in the header of \"%"TS"\".\n"
 541                         "          It may be being changed by another process, or a process\n"
 542                         "          may have crashed while writing the WIM.", in_wim_path);
 543         }
 544
 545         if (open_flags & WIMLIB_OPEN_FLAG_WRITE_ACCESS) {
 546                 ret = can_modify_wim(w);
 547                 if (ret)
 548                         return ret;
 549         }
 550
 551         if (w->hdr.total_parts != 1 && !(open_flags & WIMLIB_OPEN_FLAG_SPLIT_OK)) {
 552                 ERROR("\"%"TS"\": This WIM is part %u of a %u-part WIM",
 553                       in_wim_path, w->hdr.part_number, w->hdr.total_parts);
 554                 return WIMLIB_ERR_SPLIT_UNSUPPORTED;
 555         }
 556
 557         DEBUG("According to header, WIM contains %u images", w->hdr.image_count);
 558
 559         /* If the boot index is invalid, print a warning and set it to 0 */
 560         if (w->hdr.boot_idx > w->hdr.image_count) {
 561                 WARNING("In `%"TS"', image %u is marked as bootable, "
 562                         "but there are only %u images in the WIM",
 563                         in_wim_path, w->hdr.boot_idx, w->hdr.image_count);
 564                 w->hdr.boot_idx = 0;
 565         }
 566
 567         /* Check and cache the compression type */
 568         if (w->hdr.flags & WIM_HDR_FLAG_COMPRESSION) {
 569                 if (w->hdr.flags & WIM_HDR_FLAG_COMPRESS_LZX) {
 570                         if (w->hdr.flags & WIM_HDR_FLAG_COMPRESS_XPRESS) {
 571                                 ERROR("Multiple compression flags are set in \"%"TS"\"",
 572                                       in_wim_path);
 573                                 return WIMLIB_ERR_INVALID_COMPRESSION_TYPE;
 574                         }
 575                         w->compression_type = WIMLIB_COMPRESSION_TYPE_LZX;
 576                 } else if (w->hdr.flags & WIM_HDR_FLAG_COMPRESS_XPRESS) {
 577                         w->compression_type = WIMLIB_COMPRESSION_TYPE_XPRESS;
 578                 } else {
 579                         ERROR("The compression flag is set on \"%"TS"\", but "
 580                               "neither the XPRESS nor LZX flag is set",
 581                               in_wim_path);
 582                         return WIMLIB_ERR_INVALID_COMPRESSION_TYPE;
 583                 }
 584         } else {
 585                 BUILD_BUG_ON(WIMLIB_COMPRESSION_TYPE_NONE != 0);
 586         }
 587
 588         if (open_flags & WIMLIB_OPEN_FLAG_CHECK_INTEGRITY) {
 589                 ret = check_wim_integrity(w, progress_func);
 590                 if (ret == WIM_INTEGRITY_NONEXISTENT) {
 591                         WARNING("No integrity information for `%"TS"'; skipping "
 592                                 "integrity check.", in_wim_path);
 593                 } else if (ret == WIM_INTEGRITY_NOT_OK) {
 594                         ERROR("WIM is not intact! (Failed integrity check)");
 595                         return WIMLIB_ERR_INTEGRITY;
 596                 } else if (ret != WIM_INTEGRITY_OK) {
 597                         return ret;
 598                 }
 599         }
 600
 601         if (w->hdr.image_count != 0 && w->hdr.part_number == 1) {
 602                 w->image_metadata = new_image_metadata_array(w->hdr.image_count);
 603                 if (!w->image_metadata)
 604                         return WIMLIB_ERR_NOMEM;
 605         }
 606
 607         ret = read_lookup_table(w);
 608         if (ret)
 609                 return ret;
 610
 611         ret = read_xml_data(w->in_fd, &w->hdr.xml_res_entry, &w->wim_info);
 612         if (ret)
 613                 return ret;
 614
 615         xml_num_images = wim_info_get_num_images(w->wim_info);
 616         if (xml_num_images != w->hdr.image_count) {
 617                 ERROR("In the file `%"TS"', there are %u <IMAGE> elements "
 618                       "in the XML data,", in_wim_path, xml_num_images);
 619                 ERROR("but %u images in the WIM!  There must be exactly one "
 620                       "<IMAGE> element per image.", w->hdr.image_count);
 621                 return WIMLIB_ERR_IMAGE_COUNT;
 622         }
 623
 624         DEBUG("Done beginning read of WIM file `%"TS"'.", in_wim_path);
 625         return 0;
 626 }
 627
 628 /*
 629  * Opens a WIM file and creates a WIMStruct for it.
 630  */
 631 WIMLIBAPI int
 632 wimlib_open_wim(const tchar *wim_file, int open_flags,
 633                 WIMStruct **wim_ret,
 634                 wimlib_progress_func_t progress_func)
 635 {
 636         WIMStruct *wim;
 637         int ret;
 638
 639         wimlib_global_init(WIMLIB_INIT_FLAG_ASSUME_UTF8);
 640
 641         ret = WIMLIB_ERR_INVALID_PARAM;
 642         if (!wim_file || !wim_ret)
 643                 goto out;
 644
 645         ret = WIMLIB_ERR_NOMEM;
 646         wim = new_wim_struct();
 647         if (!wim)
 648                 goto out;
 649
 650         ret = begin_read(wim, wim_file, open_flags, progress_func);
 651         if (ret)
 652                 goto out_wimlib_free;
 653
 654         ret = 0;
 655         *wim_ret = wim;
 656         goto out;
 657 out_wimlib_free:
 658         wimlib_free(wim);
 659 out:
 660         return ret;
 661 }
 662
 663 void
 664 destroy_image_metadata(struct wim_image_metadata *imd,
 665                        struct wim_lookup_table *table,
 666                        bool free_metadata_lte)
 667 {
 668         free_dentry_tree(imd->root_dentry, table);
 669         imd->root_dentry = NULL;
 670         free_wim_security_data(imd->security_data);
 671         imd->security_data = NULL;
 672
 673         if (free_metadata_lte) {
 674                 free_lookup_table_entry(imd->metadata_lte);
 675                 imd->metadata_lte = NULL;
 676         }
 677         if (!table) {
 678                 struct wim_lookup_table_entry *lte, *tmp;
 679                 list_for_each_entry_safe(lte, tmp, &imd->unhashed_streams, unhashed_list)
 680                         free_lookup_table_entry(lte);
 681         }
 682         INIT_LIST_HEAD(&imd->unhashed_streams);
 683         INIT_LIST_HEAD(&imd->inode_list);
 684 #ifdef WITH_NTFS_3G
 685         if (imd->ntfs_vol) {
 686                 do_ntfs_umount(imd->ntfs_vol);
 687                 imd->ntfs_vol = NULL;
 688         }
 689 #endif
 690 }
 691
 692 void
 693 put_image_metadata(struct wim_image_metadata *imd,
 694                    struct wim_lookup_table *table)
 695 {
 696         if (imd && --imd->refcnt == 0) {
 697                 destroy_image_metadata(imd, table, true);
 698                 FREE(imd);
 699         }
 700 }
 701
 702 /* Appends the specified image metadata structure to the array of image metadata
 703  * for a WIM, and increments the image count. */
 704 int
 705 append_image_metadata(WIMStruct *w, struct wim_image_metadata *imd)
 706 {
 707         struct wim_image_metadata **imd_array;
 708
 709         DEBUG("Reallocating image metadata array for image_count = %u",
 710               w->hdr.image_count + 1);
 711         imd_array = REALLOC(w->image_metadata,
 712                             sizeof(w->image_metadata[0]) * (w->hdr.image_count + 1));
 713
 714         if (!imd_array)
 715                 return WIMLIB_ERR_NOMEM;
 716         w->image_metadata = imd_array;
 717         imd_array[w->hdr.image_count++] = imd;
 718         return 0;
 719 }
 720
 721
 722 struct wim_image_metadata *
 723 new_image_metadata(void)
 724 {
 725         struct wim_image_metadata *imd;
 726
 727         imd = CALLOC(1, sizeof(*imd));
 728         if (imd) {
 729                 imd->refcnt = 1;
 730                 INIT_LIST_HEAD(&imd->inode_list);
 731                 INIT_LIST_HEAD(&imd->unhashed_streams);
 732                 DEBUG("Created new image metadata (refcnt=1)");
 733         } else {
 734                 ERROR_WITH_ERRNO("Failed to allocate new image metadata structure");
 735         }
 736         return imd;
 737 }
 738
 739 struct wim_image_metadata **
 740 new_image_metadata_array(unsigned num_images)
 741 {
 742         struct wim_image_metadata **imd_array;
 743
 744         DEBUG("Creating new image metadata array for %u images",
 745               num_images);
 746
 747         imd_array = CALLOC(num_images, sizeof(imd_array[0]));
 748
 749         if (!imd_array) {
 750                 ERROR("Failed to allocate memory for %u image metadata structures",
 751                       num_images);
 752                 return NULL;
 753         }
 754         for (unsigned i = 0; i < num_images; i++) {
 755                 imd_array[i] = new_image_metadata();
 756                 if (!imd_array[i]) {
 757                         for (unsigned j = 0; j < i; j++)
 758                                 put_image_metadata(imd_array[j], NULL);
 759                         FREE(imd_array);
 760                         return NULL;
 761                 }
 762         }
 763         return imd_array;
 764 }
 765
 766 /* Checksum all streams that are unhashed (other than the metadata streams),
 767  * merging them into the lookup table as needed.  This is a no-op unless the
 768  * library has previously used to add or mount an image using the same
 769  * WIMStruct. */
 770 int
 771 wim_checksum_unhashed_streams(WIMStruct *w)
 772 {
 773         int ret;
 774         for (int i = 0; i < w->hdr.image_count; i++) {
 775                 struct wim_lookup_table_entry *lte, *tmp;
 776                 struct wim_image_metadata *imd = w->image_metadata[i];
 777                 image_for_each_unhashed_stream_safe(lte, tmp, imd) {
 778                         ret = hash_unhashed_stream(lte, w->lookup_table, NULL);
 779                         if (ret)
 780                                 return ret;
 781                 }
 782         }
 783         return 0;
 784 }
 785
 786 /*
 787  * can_modify_wim - Check if a given WIM is writeable.  This is only the case if
 788  * it meets the following three conditions:
 789  *
 790  * 1. Write access is allowed to the underlying file (if any) at the filesystem level.
 791  * 2. The WIM is not part of a spanned set.
 792  * 3. The WIM_HDR_FLAG_READONLY flag is not set in the WIM header.
 793  *
 794  * Return value is 0 if writable; WIMLIB_ERR_WIM_IS_READONLY otherwise.
 795  */
 796 int
 797 can_modify_wim(WIMStruct *wim)
 798 {
 799         if (wim->filename) {
 800                 if (taccess(wim->filename, W_OK)) {
 801                         ERROR_WITH_ERRNO("Can't modify \"%"TS"\"", wim->filename);
 802                         return WIMLIB_ERR_WIM_IS_READONLY;
 803                 }
 804         }
 805         if (wim->hdr.total_parts != 1) {
 806                 ERROR("Cannot modify \"%"TS"\": is part of a spanned set",
 807                       wim->filename);
 808                 return WIMLIB_ERR_WIM_IS_READONLY;
 809         }
 810         if (wim->hdr.flags & WIM_HDR_FLAG_READONLY) {
 811                 ERROR("Cannot modify \"%"TS"\": is marked read-only",
 812                       wim->filename);
 813                 return WIMLIB_ERR_WIM_IS_READONLY;
 814         }
 815         return 0;
 816 }
 817
 818 /*
 819  * can_delete_from_wim - Check if files or images can be deleted from a given
 820  * WIM file.
 821  *
 822  * This theoretically should be exactly the same as can_modify_wim(), but
 823  * unfortunately, due to bugs in Microsoft's software that generate incorrect
 824  * reference counts for some WIM resources, we need to run expensive
 825  * verifications to make sure the reference counts are correct on all WIM
 826  * resources.  Otherwise we might delete a WIM resource whose reference count
 827  * has fallen to 0, but is actually still referenced somewhere.
 828  */
 829 int
 830 can_delete_from_wim(WIMStruct *wim)
 831 {
 832         int ret;
 833
 834         ret = can_modify_wim(wim);
 835         if (ret)
 836                 return ret;
 837         if (!wim->refcnts_ok)
 838                 wim_recalculate_refcnts(wim);
 839         return 0;
 840 }
 841
 842 /* Frees the memory for the WIMStruct, including all internal memory; also
 843  * closes all files associated with the WIMStruct.  */
 844 WIMLIBAPI void
 845 wimlib_free(WIMStruct *w)
 846 {
 847         DEBUG("Freeing WIMStruct");
 848
 849         if (!w)
 850                 return;
 851         if (w->in_fd != -1)
 852                 close(w->in_fd);
 853         if (w->out_fd != -1)
 854                 close(w->out_fd);
 855
 856         free_lookup_table(w->lookup_table);
 857
 858         FREE(w->filename);
 859         free_wim_info(w->wim_info);
 860         if (w->image_metadata) {
 861                 for (unsigned i = 0; i < w->hdr.image_count; i++)
 862                         put_image_metadata(w->image_metadata[i], NULL);
 863                 FREE(w->image_metadata);
 864         }
 865         FREE(w);
 866         DEBUG("Freed WIMStruct");
 867 }
 868
 869 static bool
 870 test_locale_ctype_utf8(void)
 871 {
 872 #ifdef __WIN32__
 873         return false;
 874 #else
 875         char *ctype = nl_langinfo(CODESET);
 876
 877         return (!strstr(ctype, "UTF-8") ||
 878                 !strstr(ctype, "UTF8") ||
 879                 !strstr(ctype, "utf8") ||
 880                 !strstr(ctype, "utf-8"));
 881 #endif
 882 }
 883
 884 WIMLIBAPI int
 885 wimlib_global_init(int init_flags)
 886 {
 887         static bool already_inited = false;
 888
 889         if (already_inited)
 890                 return 0;
 891         libxml_global_init();
 892         if (!(init_flags & WIMLIB_INIT_FLAG_ASSUME_UTF8)) {
 893                 wimlib_mbs_is_utf8 = test_locale_ctype_utf8();
 894         #ifdef WITH_NTFS_3G
 895                 if (!wimlib_mbs_is_utf8)
 896                         libntfs3g_global_init();
 897         #endif
 898         }
 899 #ifdef __WIN32__
 900         win32_global_init();
 901 #endif
 902         already_inited = true;
 903         return 0;
 904 }
 905
 906 /* Free global memory allocations.  Not strictly necessary if the process using
 907  * wimlib is just about to exit (as is the case for 'imagex'). */
 908 WIMLIBAPI void
 909 wimlib_global_cleanup(void)
 910 {
 911         libxml_global_cleanup();
 912         iconv_global_cleanup();
 913 #ifdef __WIN32__
 914         win32_global_cleanup();
 915 #endif
 916 }