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   1 /*
   2  * wim.c - High-level code dealing with WIMStructs and images.
   3  */
   4
   5 /*
   6  * Copyright (C) 2012, 2013, 2014 Eric Biggers
   7  *
   8  * This file is free software; you can redistribute it and/or modify it under
   9  * the terms of the GNU Lesser General Public License as published by the Free
  10  * Software Foundation; either version 3 of the License, or (at your option) any
  11  * later version.
  12  *
  13  * This file is distributed in the hope that it will be useful, but WITHOUT
  14  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  15  * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
  16  * details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public License
  19  * along with this file; if not, see http://www.gnu.org/licenses/.
  20  */
  21
  22 #ifdef HAVE_CONFIG_H
  23 #  include "config.h"
  24 #endif
  25
  26 #include <errno.h>
  27 #include <fcntl.h>
  28 #ifndef __WIN32__
  29 #  include <langinfo.h>
  30 #endif
  31 #include <stdlib.h>
  32 #include <unistd.h>
  33
  34 #include "wimlib.h"
  35 #include "wimlib/assert.h"
  36 #include "wimlib/bitops.h"
  37 #include "wimlib/dentry.h"
  38 #include "wimlib/encoding.h"
  39 #include "wimlib/file_io.h"
  40 #include "wimlib/integrity.h"
  41 #include "wimlib/lookup_table.h"
  42 #include "wimlib/metadata.h"
  43 #ifdef WITH_NTFS_3G
  44 #  include "wimlib/ntfs_3g.h" /* for do_ntfs_umount() */
  45 #endif
  46 #include "wimlib/security.h"
  47 #include "wimlib/wim.h"
  48 #include "wimlib/xml.h"
  49 #ifdef __WIN32__
  50 #  include "wimlib/win32.h" /* for realpath() replacement */
  51 #endif
  52
  53 static int
  54 wim_default_solid_compression_type(void)
  55 {
  56         return WIMLIB_COMPRESSION_TYPE_LZMS;
  57 }
  58
  59 static u32
  60 wim_default_solid_chunk_size(int ctype) {
  61         switch (ctype) {
  62         case WIMLIB_COMPRESSION_TYPE_LZMS:
  63                 return 1U << 25; /* 33554432  */
  64         default:
  65                 return 1U << 15; /* 32768     */
  66         }
  67 }
  68
  69 static WIMStruct *
  70 new_wim_struct(void)
  71 {
  72         WIMStruct *wim = CALLOC(1, sizeof(WIMStruct));
  73         if (!wim)
  74                 return NULL;
  75
  76         filedes_invalidate(&wim->in_fd);
  77         filedes_invalidate(&wim->out_fd);
  78         wim->out_solid_compression_type = wim_default_solid_compression_type();
  79         wim->out_solid_chunk_size = wim_default_solid_chunk_size(
  80                                         wim->out_solid_compression_type);
  81         INIT_LIST_HEAD(&wim->subwims);
  82         return wim;
  83 }
  84
  85 /* Determine if the chunk size is valid for the specified compression type.  */
  86 static bool
  87 wim_chunk_size_valid(u32 chunk_size, int ctype)
  88 {
  89         u32 order;
  90
  91         /* Chunk size is meaningless for uncompressed WIMs --- any value is
  92          * okay.  */
  93         if (ctype == WIMLIB_COMPRESSION_TYPE_NONE)
  94                 return true;
  95
  96         /* Chunk size must be power of 2.  */
  97         if (chunk_size == 0)
  98                 return false;
  99         order = fls32(chunk_size);
 100         if (chunk_size != 1U << order)
 101                 return false;
 102
 103         /* Order        Size
 104          * =====        ====
 105          * 15           32768
 106          * 16           65536
 107          * 17           131072
 108          * 18           262144
 109          * 19           524288
 110          * 20           1048576
 111          * 21           2097152
 112          * 22           4194304
 113          * 23           8388608
 114          * 24           16777216
 115          * 25           33554432
 116          * 26           67108864
 117          */
 118
 119         /* See the documentation for the --chunk-size option of `wimlib-imagex
 120          * capture' for information about allowed chunk sizes.  */
 121         switch (ctype) {
 122         case WIMLIB_COMPRESSION_TYPE_LZX:
 123                 return order >= 15 && order <= 21;
 124         case WIMLIB_COMPRESSION_TYPE_XPRESS:
 125                 return order >= 12 && order <= 16;
 126         case WIMLIB_COMPRESSION_TYPE_LZMS:
 127                 return order >= 15 && order <= 30;
 128         }
 129         return false;
 130 }
 131
 132 /* Return the default chunk size to use for the specified compression type.
 133  *
 134  * See notes above in wim_chunk_size_valid().  */
 135 static u32
 136 wim_default_chunk_size(int ctype)
 137 {
 138         switch (ctype) {
 139         case WIMLIB_COMPRESSION_TYPE_LZMS:
 140                 return 1U << 17; /* 131072  */
 141         default:
 142                 return 1U << 15; /* 32768   */
 143         }
 144 }
 145
 146 /*
 147  * Calls a function on images in the WIM.  If @image is WIMLIB_ALL_IMAGES,
 148  * @visitor is called on the WIM once for each image, with each image selected
 149  * as the current image in turn.  If @image is a certain image, @visitor is
 150  * called on the WIM only once, with that image selected.
 151  */
 152 int
 153 for_image(WIMStruct *wim, int image, int (*visitor)(WIMStruct *))
 154 {
 155         int ret;
 156         int start;
 157         int end;
 158         int i;
 159
 160         if (image == WIMLIB_ALL_IMAGES) {
 161                 start = 1;
 162                 end = wim->hdr.image_count;
 163         } else if (image >= 1 && image <= wim->hdr.image_count) {
 164                 start = image;
 165                 end = image;
 166         } else {
 167                 return WIMLIB_ERR_INVALID_IMAGE;
 168         }
 169         for (i = start; i <= end; i++) {
 170                 ret = select_wim_image(wim, i);
 171                 if (ret != 0)
 172                         return ret;
 173                 ret = visitor(wim);
 174                 if (ret != 0)
 175                         return ret;
 176         }
 177         return 0;
 178 }
 179
 180 /* API function documented in wimlib.h  */
 181 WIMLIBAPI int
 182 wimlib_create_new_wim(int ctype, WIMStruct **wim_ret)
 183 {
 184         WIMStruct *wim;
 185         struct wim_lookup_table *table;
 186         int ret;
 187
 188         ret = wimlib_global_init(WIMLIB_INIT_FLAG_ASSUME_UTF8);
 189         if (ret)
 190                 return ret;
 191
 192         wim = new_wim_struct();
 193         if (!wim)
 194                 return WIMLIB_ERR_NOMEM;
 195
 196         ret = init_wim_header(&wim->hdr, ctype, wim_default_chunk_size(ctype));
 197         if (ret)
 198                 goto out_free_wim;
 199
 200         table = new_lookup_table(9001);
 201         if (!table) {
 202                 ret = WIMLIB_ERR_NOMEM;
 203                 goto out_free_wim;
 204         }
 205         wim->lookup_table = table;
 206         wim->compression_type = ctype;
 207         wim->out_compression_type = ctype;
 208         wim->chunk_size = wim->hdr.chunk_size;
 209         wim->out_chunk_size = wim->hdr.chunk_size;
 210         *wim_ret = wim;
 211         return 0;
 212
 213 out_free_wim:
 214         FREE(wim);
 215         return ret;
 216 }
 217
 218 static void
 219 destroy_image_metadata(struct wim_image_metadata *imd,
 220                        struct wim_lookup_table *table,
 221                        bool free_metadata_lte)
 222 {
 223         free_dentry_tree(imd->root_dentry, table);
 224         imd->root_dentry = NULL;
 225         free_wim_security_data(imd->security_data);
 226         imd->security_data = NULL;
 227
 228         if (free_metadata_lte) {
 229                 free_lookup_table_entry(imd->metadata_lte);
 230                 imd->metadata_lte = NULL;
 231         }
 232         if (!table) {
 233                 struct wim_lookup_table_entry *lte, *tmp;
 234                 list_for_each_entry_safe(lte, tmp, &imd->unhashed_streams, unhashed_list)
 235                         free_lookup_table_entry(lte);
 236         }
 237         INIT_LIST_HEAD(&imd->unhashed_streams);
 238         INIT_LIST_HEAD(&imd->inode_list);
 239 #ifdef WITH_NTFS_3G
 240         if (imd->ntfs_vol) {
 241                 do_ntfs_umount(imd->ntfs_vol);
 242                 imd->ntfs_vol = NULL;
 243         }
 244 #endif
 245 }
 246
 247 void
 248 put_image_metadata(struct wim_image_metadata *imd,
 249                    struct wim_lookup_table *table)
 250 {
 251         if (imd && --imd->refcnt == 0) {
 252                 destroy_image_metadata(imd, table, true);
 253                 FREE(imd);
 254         }
 255 }
 256
 257 /* Appends the specified image metadata structure to the array of image metadata
 258  * for a WIM, and increments the image count. */
 259 int
 260 append_image_metadata(WIMStruct *wim, struct wim_image_metadata *imd)
 261 {
 262         struct wim_image_metadata **imd_array;
 263
 264         imd_array = REALLOC(wim->image_metadata,
 265                             sizeof(wim->image_metadata[0]) * (wim->hdr.image_count + 1));
 266
 267         if (!imd_array)
 268                 return WIMLIB_ERR_NOMEM;
 269         wim->image_metadata = imd_array;
 270         imd_array[wim->hdr.image_count++] = imd;
 271         return 0;
 272 }
 273
 274 struct wim_image_metadata *
 275 new_image_metadata(void)
 276 {
 277         struct wim_image_metadata *imd;
 278
 279         imd = CALLOC(1, sizeof(*imd));
 280         if (imd) {
 281                 imd->refcnt = 1;
 282                 INIT_LIST_HEAD(&imd->inode_list);
 283                 INIT_LIST_HEAD(&imd->unhashed_streams);
 284         }
 285         return imd;
 286 }
 287
 288 static struct wim_image_metadata **
 289 new_image_metadata_array(unsigned num_images)
 290 {
 291         struct wim_image_metadata **imd_array;
 292
 293         imd_array = CALLOC(num_images, sizeof(imd_array[0]));
 294
 295         if (!imd_array)
 296                 return NULL;
 297         for (unsigned i = 0; i < num_images; i++) {
 298                 imd_array[i] = new_image_metadata();
 299                 if (unlikely(!imd_array[i])) {
 300                         for (unsigned j = 0; j < i; j++)
 301                                 put_image_metadata(imd_array[j], NULL);
 302                         FREE(imd_array);
 303                         return NULL;
 304                 }
 305         }
 306         return imd_array;
 307 }
 308
 309
 310 /*
 311  * Load the metadata for the specified WIM image into memory and set it
 312  * as the WIMStruct's currently selected image.
 313  *
 314  * @wim
 315  *      The WIMStruct for the WIM.
 316  * @image
 317  *      The 1-based index of the image in the WIM to select.
 318  *
 319  * On success, 0 will be returned, wim->current_image will be set to
 320  * @image, and wim_get_current_image_metadata() can be used to retrieve
 321  * metadata information for the image.
 322  *
 323  * On failure, WIMLIB_ERR_INVALID_IMAGE, WIMLIB_ERR_METADATA_NOT_FOUND,
 324  * or another error code will be returned.
 325  */
 326 int
 327 select_wim_image(WIMStruct *wim, int image)
 328 {
 329         struct wim_image_metadata *imd;
 330         int ret;
 331
 332         if (image == WIMLIB_NO_IMAGE)
 333                 return WIMLIB_ERR_INVALID_IMAGE;
 334
 335         if (image == wim->current_image)
 336                 return 0;
 337
 338         if (image < 1 || image > wim->hdr.image_count)
 339                 return WIMLIB_ERR_INVALID_IMAGE;
 340
 341         if (!wim_has_metadata(wim))
 342                 return WIMLIB_ERR_METADATA_NOT_FOUND;
 343
 344         /* If a valid image is currently selected, its metadata can be freed if
 345          * it has not been modified.  */
 346         deselect_current_wim_image(wim);
 347         wim->current_image = image;
 348         imd = wim_get_current_image_metadata(wim);
 349         if (imd->root_dentry || imd->modified) {
 350                 ret = 0;
 351         } else {
 352                 ret = read_metadata_resource(imd);
 353                 if (ret)
 354                         wim->current_image = WIMLIB_NO_IMAGE;
 355         }
 356         return ret;
 357 }
 358
 359 void
 360 deselect_current_wim_image(WIMStruct *wim)
 361 {
 362         struct wim_image_metadata *imd;
 363         if (wim->current_image == WIMLIB_NO_IMAGE)
 364                 return;
 365         imd = wim_get_current_image_metadata(wim);
 366         if (!imd->modified) {
 367                 wimlib_assert(list_empty(&imd->unhashed_streams));
 368                 destroy_image_metadata(imd, NULL, false);
 369         }
 370         wim->current_image = WIMLIB_NO_IMAGE;
 371 }
 372
 373 /* API function documented in wimlib.h  */
 374 WIMLIBAPI const tchar *
 375 wimlib_get_compression_type_string(int ctype)
 376 {
 377         switch (ctype) {
 378         case WIMLIB_COMPRESSION_TYPE_NONE:
 379                 return T("None");
 380         case WIMLIB_COMPRESSION_TYPE_XPRESS:
 381                 return T("XPRESS");
 382         case WIMLIB_COMPRESSION_TYPE_LZX:
 383                 return T("LZX");
 384         case WIMLIB_COMPRESSION_TYPE_LZMS:
 385                 return T("LZMS");
 386         default:
 387                 return T("Invalid");
 388         }
 389 }
 390
 391 /* API function documented in wimlib.h  */
 392 WIMLIBAPI int
 393 wimlib_resolve_image(WIMStruct *wim, const tchar *image_name_or_num)
 394 {
 395         tchar *p;
 396         long image;
 397         int i;
 398
 399         if (!image_name_or_num || !*image_name_or_num)
 400                 return WIMLIB_NO_IMAGE;
 401
 402         if (!tstrcasecmp(image_name_or_num, T("all"))
 403             || !tstrcasecmp(image_name_or_num, T("*")))
 404                 return WIMLIB_ALL_IMAGES;
 405         image = tstrtol(image_name_or_num, &p, 10);
 406         if (p != image_name_or_num && *p == T('\0') && image > 0) {
 407                 if (image > wim->hdr.image_count)
 408                         return WIMLIB_NO_IMAGE;
 409                 return image;
 410         } else {
 411                 for (i = 1; i <= wim->hdr.image_count; i++) {
 412                         if (!tstrcmp(image_name_or_num,
 413                                      wimlib_get_image_name(wim, i)))
 414                                 return i;
 415                 }
 416                 return WIMLIB_NO_IMAGE;
 417         }
 418 }
 419
 420 /* API function documented in wimlib.h  */
 421 WIMLIBAPI void
 422 wimlib_print_available_images(const WIMStruct *wim, int image)
 423 {
 424         int first;
 425         int last;
 426         int i;
 427         int n;
 428         if (image == WIMLIB_ALL_IMAGES) {
 429                 n = tprintf(T("Available Images:\n"));
 430                 first = 1;
 431                 last = wim->hdr.image_count;
 432         } else if (image >= 1 && image <= wim->hdr.image_count) {
 433                 n = tprintf(T("Information for Image %d\n"), image);
 434                 first = image;
 435                 last = image;
 436         } else {
 437                 tprintf(T("wimlib_print_available_images(): Invalid image %d"),
 438                         image);
 439                 return;
 440         }
 441         for (i = 0; i < n - 1; i++)
 442                 tputchar(T('-'));
 443         tputchar(T('\n'));
 444         for (i = first; i <= last; i++)
 445                 print_image_info(wim->wim_info, i);
 446 }
 447
 448 /* API function documented in wimlib.h  */
 449 WIMLIBAPI int
 450 wimlib_get_wim_info(WIMStruct *wim, struct wimlib_wim_info *info)
 451 {
 452         memset(info, 0, sizeof(struct wimlib_wim_info));
 453         memcpy(info->guid, wim->hdr.guid, WIMLIB_GUID_LEN);
 454         info->image_count = wim->hdr.image_count;
 455         info->boot_index = wim->hdr.boot_idx;
 456         info->wim_version = wim->hdr.wim_version;
 457         info->chunk_size = wim->chunk_size;
 458         info->part_number = wim->hdr.part_number;
 459         info->total_parts = wim->hdr.total_parts;
 460         info->compression_type = wim->compression_type;
 461         info->total_bytes = wim_info_get_total_bytes(wim->wim_info);
 462         info->has_integrity_table = wim_has_integrity_table(wim);
 463         info->opened_from_file = (wim->filename != NULL);
 464         info->is_readonly = (wim->hdr.flags & WIM_HDR_FLAG_READONLY) ||
 465                              (wim->hdr.total_parts != 1) ||
 466                              (wim->filename && taccess(wim->filename, W_OK));
 467         info->has_rpfix = (wim->hdr.flags & WIM_HDR_FLAG_RP_FIX) != 0;
 468         info->is_marked_readonly = (wim->hdr.flags & WIM_HDR_FLAG_READONLY) != 0;
 469         info->write_in_progress = (wim->hdr.flags & WIM_HDR_FLAG_WRITE_IN_PROGRESS) != 0;
 470         info->metadata_only = (wim->hdr.flags & WIM_HDR_FLAG_METADATA_ONLY) != 0;
 471         info->resource_only = (wim->hdr.flags & WIM_HDR_FLAG_RESOURCE_ONLY) != 0;
 472         info->spanned = (wim->hdr.flags & WIM_HDR_FLAG_SPANNED) != 0;
 473         info->pipable = wim_is_pipable(wim);
 474         return 0;
 475 }
 476
 477 /* API function documented in wimlib.h  */
 478 WIMLIBAPI int
 479 wimlib_set_wim_info(WIMStruct *wim, const struct wimlib_wim_info *info, int which)
 480 {
 481         if (which & ~(WIMLIB_CHANGE_READONLY_FLAG |
 482                       WIMLIB_CHANGE_GUID |
 483                       WIMLIB_CHANGE_BOOT_INDEX |
 484                       WIMLIB_CHANGE_RPFIX_FLAG))
 485                 return WIMLIB_ERR_INVALID_PARAM;
 486
 487         if ((which & WIMLIB_CHANGE_BOOT_INDEX) &&
 488             info->boot_index > wim->hdr.image_count)
 489                 return WIMLIB_ERR_INVALID_IMAGE;
 490
 491         if (which & WIMLIB_CHANGE_READONLY_FLAG) {
 492                 if (info->is_marked_readonly)
 493                         wim->hdr.flags |= WIM_HDR_FLAG_READONLY;
 494                 else
 495                         wim->hdr.flags &= ~WIM_HDR_FLAG_READONLY;
 496         }
 497
 498         if (which & WIMLIB_CHANGE_GUID)
 499                 memcpy(wim->hdr.guid, info->guid, WIM_GUID_LEN);
 500
 501         if (which & WIMLIB_CHANGE_BOOT_INDEX)
 502                 wim->hdr.boot_idx = info->boot_index;
 503
 504         if (which & WIMLIB_CHANGE_RPFIX_FLAG) {
 505                 if (info->has_rpfix)
 506                         wim->hdr.flags |= WIM_HDR_FLAG_RP_FIX;
 507                 else
 508                         wim->hdr.flags &= ~WIM_HDR_FLAG_RP_FIX;
 509         }
 510         return 0;
 511 }
 512
 513 static int
 514 set_out_ctype(int ctype, u8 *out_ctype_p)
 515 {
 516         switch (ctype) {
 517         case WIMLIB_COMPRESSION_TYPE_NONE:
 518         case WIMLIB_COMPRESSION_TYPE_LZX:
 519         case WIMLIB_COMPRESSION_TYPE_XPRESS:
 520         case WIMLIB_COMPRESSION_TYPE_LZMS:
 521                 *out_ctype_p = ctype;
 522                 return 0;
 523         }
 524         return WIMLIB_ERR_INVALID_COMPRESSION_TYPE;
 525 }
 526
 527 /* API function documented in wimlib.h  */
 528 WIMLIBAPI int
 529 wimlib_set_output_compression_type(WIMStruct *wim, int ctype)
 530 {
 531         int ret = set_out_ctype(ctype, &wim->out_compression_type);
 532         if (ret)
 533                 return ret;
 534
 535         /* Reset the chunk size if it's no longer valid.  */
 536         if (!wim_chunk_size_valid(wim->out_chunk_size, ctype))
 537                 wim->out_chunk_size = wim_default_chunk_size(ctype);
 538         return 0;
 539 }
 540
 541 /* API function documented in wimlib.h  */
 542 WIMLIBAPI int
 543 wimlib_set_output_pack_compression_type(WIMStruct *wim, int ctype)
 544 {
 545         int ret = set_out_ctype(ctype, &wim->out_solid_compression_type);
 546         if (ret)
 547                 return ret;
 548
 549         /* Reset the chunk size if it's no longer valid.  */
 550         if (!wim_chunk_size_valid(wim->out_solid_chunk_size, ctype))
 551                 wim->out_solid_chunk_size = wim_default_solid_chunk_size(ctype);
 552         return 0;
 553 }
 554
 555 static int
 556 set_out_chunk_size(u32 chunk_size, int ctype, u32 *out_chunk_size_p)
 557 {
 558         if (!wim_chunk_size_valid(chunk_size, ctype))
 559                 return WIMLIB_ERR_INVALID_CHUNK_SIZE;
 560
 561         *out_chunk_size_p = chunk_size;
 562         return 0;
 563 }
 564
 565 /* API function documented in wimlib.h  */
 566 WIMLIBAPI int
 567 wimlib_set_output_chunk_size(WIMStruct *wim, uint32_t chunk_size)
 568 {
 569         if (chunk_size == 0) {
 570                 wim->out_chunk_size =
 571                         wim_default_chunk_size(wim->out_compression_type);
 572                 return 0;
 573         }
 574
 575         return set_out_chunk_size(chunk_size,
 576                                   wim->out_compression_type,
 577                                   &wim->out_chunk_size);
 578 }
 579
 580 /* API function documented in wimlib.h  */
 581 WIMLIBAPI int
 582 wimlib_set_output_pack_chunk_size(WIMStruct *wim, uint32_t chunk_size)
 583 {
 584         if (chunk_size == 0) {
 585                 wim->out_solid_chunk_size =
 586                         wim_default_solid_chunk_size(wim->out_solid_compression_type);
 587                 return 0;
 588         }
 589
 590         return set_out_chunk_size(chunk_size,
 591                                   wim->out_solid_compression_type,
 592                                   &wim->out_solid_chunk_size);
 593 }
 594
 595 WIMLIBAPI void
 596 wimlib_register_progress_function(WIMStruct *wim,
 597                                   wimlib_progress_func_t progfunc,
 598                                   void *progctx)
 599 {
 600         wim->progfunc = progfunc;
 601         wim->progctx = progctx;
 602 }
 603
 604 static int
 605 open_wim_file(const tchar *filename, struct filedes *fd_ret)
 606 {
 607         int raw_fd;
 608
 609         raw_fd = topen(filename, O_RDONLY | O_BINARY);
 610         if (raw_fd < 0) {
 611                 ERROR_WITH_ERRNO("Can't open \"%"TS"\" read-only", filename);
 612                 return WIMLIB_ERR_OPEN;
 613         }
 614         filedes_init(fd_ret, raw_fd);
 615         return 0;
 616 }
 617
 618 /*
 619  * Begins the reading of a WIM file; opens the file and reads its header and
 620  * lookup table, and optionally checks the integrity.
 621  */
 622 static int
 623 begin_read(WIMStruct *wim, const void *wim_filename_or_fd, int open_flags)
 624 {
 625         int ret;
 626         int xml_num_images;
 627         const tchar *wimfile;
 628
 629         if (open_flags & WIMLIB_OPEN_FLAG_FROM_PIPE) {
 630                 wimfile = NULL;
 631                 filedes_init(&wim->in_fd, *(const int*)wim_filename_or_fd);
 632                 wim->in_fd.is_pipe = 1;
 633         } else {
 634                 wimfile = wim_filename_or_fd;
 635                 ret = open_wim_file(wimfile, &wim->in_fd);
 636                 if (ret)
 637                         return ret;
 638
 639                 /* The absolute path to the WIM is requested so that
 640                  * wimlib_overwrite() still works even if the process changes
 641                  * its working directory.  This actually happens if a WIM is
 642                  * mounted read-write, since the FUSE thread changes directory
 643                  * to "/", and it needs to be able to find the WIM file again.
 644                  *
 645                  * This will break if the full path to the WIM changes in the
 646                  * intervening time...
 647                  *
 648                  * Warning: in Windows native builds, realpath() calls the
 649                  * replacement function in win32_replacements.c.
 650                  */
 651                 wim->filename = realpath(wimfile, NULL);
 652                 if (!wim->filename) {
 653                         ERROR_WITH_ERRNO("Failed to get full path to file "
 654                                          "\"%"TS"\"", wimfile);
 655                         if (errno == ENOMEM)
 656                                 return WIMLIB_ERR_NOMEM;
 657                         else
 658                                 return WIMLIB_ERR_NO_FILENAME;
 659                 }
 660         }
 661
 662         ret = read_wim_header(wim, &wim->hdr);
 663         if (ret)
 664                 return ret;
 665
 666         if (wim->hdr.flags & WIM_HDR_FLAG_WRITE_IN_PROGRESS) {
 667                 WARNING("The WIM_HDR_FLAG_WRITE_IN_PROGRESS flag is set in the header of\n"
 668                         "          \"%"TS"\".  It may be being changed by another process,\n"
 669                         "          or a process may have crashed while writing the WIM.",
 670                         wimfile);
 671         }
 672
 673         if (open_flags & WIMLIB_OPEN_FLAG_WRITE_ACCESS) {
 674                 ret = can_modify_wim(wim);
 675                 if (ret)
 676                         return ret;
 677         }
 678
 679         if ((open_flags & WIMLIB_OPEN_FLAG_ERROR_IF_SPLIT) &&
 680             (wim->hdr.total_parts != 1))
 681                 return WIMLIB_ERR_IS_SPLIT_WIM;
 682
 683         /* If the boot index is invalid, print a warning and set it to 0 */
 684         if (wim->hdr.boot_idx > wim->hdr.image_count) {
 685                 WARNING("Ignoring invalid boot index.");
 686                 wim->hdr.boot_idx = 0;
 687         }
 688
 689         /* Check and cache the compression type */
 690         if (wim->hdr.flags & WIM_HDR_FLAG_COMPRESSION) {
 691                 if (wim->hdr.flags & WIM_HDR_FLAG_COMPRESS_LZX) {
 692                         wim->compression_type = WIMLIB_COMPRESSION_TYPE_LZX;
 693                 } else if (wim->hdr.flags & (WIM_HDR_FLAG_COMPRESS_XPRESS |
 694                                              WIM_HDR_FLAG_COMPRESS_XPRESS_2)) {
 695                         wim->compression_type = WIMLIB_COMPRESSION_TYPE_XPRESS;
 696                 } else if (wim->hdr.flags & WIM_HDR_FLAG_COMPRESS_LZMS) {
 697                         wim->compression_type = WIMLIB_COMPRESSION_TYPE_LZMS;
 698                 } else {
 699                         return WIMLIB_ERR_INVALID_COMPRESSION_TYPE;
 700                 }
 701         } else {
 702                 wim->compression_type = WIMLIB_COMPRESSION_TYPE_NONE;
 703         }
 704         wim->out_compression_type = wim->compression_type;
 705
 706         /* Check and cache the chunk size.  */
 707         wim->chunk_size = wim->hdr.chunk_size;
 708         wim->out_chunk_size = wim->chunk_size;
 709         if (!wim_chunk_size_valid(wim->chunk_size, wim->compression_type)) {
 710                 ERROR("Invalid chunk size (%"PRIu32" bytes) "
 711                       "for compression type %"TS"!", wim->chunk_size,
 712                       wimlib_get_compression_type_string(wim->compression_type));
 713                 return WIMLIB_ERR_INVALID_CHUNK_SIZE;
 714         }
 715
 716         if (open_flags & WIMLIB_OPEN_FLAG_CHECK_INTEGRITY) {
 717                 ret = check_wim_integrity(wim);
 718                 if (ret == WIM_INTEGRITY_NONEXISTENT) {
 719                         WARNING("\"%"TS"\" does not contain integrity "
 720                                 "information.  Skipping integrity check.",
 721                                 wimfile);
 722                 } else if (ret == WIM_INTEGRITY_NOT_OK) {
 723                         return WIMLIB_ERR_INTEGRITY;
 724                 } else if (ret != WIM_INTEGRITY_OK) {
 725                         return ret;
 726                 }
 727         }
 728
 729         if (wim->hdr.image_count != 0 && wim->hdr.part_number == 1) {
 730                 wim->image_metadata = new_image_metadata_array(wim->hdr.image_count);
 731                 if (!wim->image_metadata)
 732                         return WIMLIB_ERR_NOMEM;
 733         }
 734
 735         if (open_flags & WIMLIB_OPEN_FLAG_FROM_PIPE) {
 736                 wim->lookup_table = new_lookup_table(9001);
 737                 if (!wim->lookup_table)
 738                         return WIMLIB_ERR_NOMEM;
 739         } else {
 740
 741                 ret = read_wim_xml_data(wim);
 742                 if (ret)
 743                         return ret;
 744
 745                 xml_num_images = wim_info_get_num_images(wim->wim_info);
 746                 if (xml_num_images != wim->hdr.image_count) {
 747                         ERROR("The WIM's header is inconsistent with its XML data.\n"
 748                               "        Please submit a bug report if you believe this "
 749                               "WIM file should be considered valid.");
 750                         return WIMLIB_ERR_IMAGE_COUNT;
 751                 }
 752
 753                 ret = read_wim_lookup_table(wim);
 754                 if (ret)
 755                         return ret;
 756         }
 757         return 0;
 758 }
 759
 760 int
 761 open_wim_as_WIMStruct(const void *wim_filename_or_fd, int open_flags,
 762                       WIMStruct **wim_ret,
 763                       wimlib_progress_func_t progfunc, void *progctx)
 764 {
 765         WIMStruct *wim;
 766         int ret;
 767
 768         ret = wimlib_global_init(WIMLIB_INIT_FLAG_ASSUME_UTF8);
 769         if (ret)
 770                 return ret;
 771
 772         wim = new_wim_struct();
 773         if (!wim)
 774                 return WIMLIB_ERR_NOMEM;
 775
 776         wim->progfunc = progfunc;
 777         wim->progctx = progctx;
 778
 779         ret = begin_read(wim, wim_filename_or_fd, open_flags);
 780         if (ret) {
 781                 wimlib_free(wim);
 782                 return ret;
 783         }
 784
 785         *wim_ret = wim;
 786         return 0;
 787 }
 788
 789 /* API function documented in wimlib.h  */
 790 WIMLIBAPI int
 791 wimlib_open_wim_with_progress(const tchar *wimfile, int open_flags,
 792                               WIMStruct **wim_ret,
 793                               wimlib_progress_func_t progfunc, void *progctx)
 794 {
 795         if (open_flags & ~(WIMLIB_OPEN_FLAG_CHECK_INTEGRITY |
 796                            WIMLIB_OPEN_FLAG_ERROR_IF_SPLIT |
 797                            WIMLIB_OPEN_FLAG_WRITE_ACCESS))
 798                 return WIMLIB_ERR_INVALID_PARAM;
 799
 800         if (!wimfile || !*wimfile || !wim_ret)
 801                 return WIMLIB_ERR_INVALID_PARAM;
 802
 803         return open_wim_as_WIMStruct(wimfile, open_flags, wim_ret,
 804                                      progfunc, progctx);
 805 }
 806
 807 /* API function documented in wimlib.h  */
 808 WIMLIBAPI int
 809 wimlib_open_wim(const tchar *wimfile, int open_flags, WIMStruct **wim_ret)
 810 {
 811         return wimlib_open_wim_with_progress(wimfile, open_flags, wim_ret,
 812                                              NULL, NULL);
 813 }
 814
 815 /* Checksum all streams that are unhashed (other than the metadata streams),
 816  * merging them into the lookup table as needed.  This is a no-op unless the
 817  * library has previously used to add or mount an image using the same
 818  * WIMStruct. */
 819 int
 820 wim_checksum_unhashed_streams(WIMStruct *wim)
 821 {
 822         int ret;
 823
 824         if (!wim_has_metadata(wim))
 825                 return 0;
 826         for (int i = 0; i < wim->hdr.image_count; i++) {
 827                 struct wim_lookup_table_entry *lte, *tmp;
 828                 struct wim_image_metadata *imd = wim->image_metadata[i];
 829                 image_for_each_unhashed_stream_safe(lte, tmp, imd) {
 830                         struct wim_lookup_table_entry *new_lte;
 831                         ret = hash_unhashed_stream(lte, wim->lookup_table, &new_lte);
 832                         if (ret)
 833                                 return ret;
 834                         if (new_lte != lte)
 835                                 free_lookup_table_entry(lte);
 836                 }
 837         }
 838         return 0;
 839 }
 840
 841 /*
 842  * can_modify_wim - Check if a given WIM is writeable.  This is only the case if
 843  * it meets the following three conditions:
 844  *
 845  * 1. Write access is allowed to the underlying file (if any) at the filesystem level.
 846  * 2. The WIM is not part of a spanned set.
 847  * 3. The WIM_HDR_FLAG_READONLY flag is not set in the WIM header.
 848  *
 849  * Return value is 0 if writable; WIMLIB_ERR_WIM_IS_READONLY otherwise.
 850  */
 851 int
 852 can_modify_wim(WIMStruct *wim)
 853 {
 854         if (wim->filename) {
 855                 if (taccess(wim->filename, W_OK)) {
 856                         ERROR_WITH_ERRNO("Can't modify \"%"TS"\"", wim->filename);
 857                         return WIMLIB_ERR_WIM_IS_READONLY;
 858                 }
 859         }
 860         if (wim->hdr.total_parts != 1) {
 861                 ERROR("Cannot modify \"%"TS"\": is part of a split WIM",
 862                       wim->filename);
 863                 return WIMLIB_ERR_WIM_IS_READONLY;
 864         }
 865         if (wim->hdr.flags & WIM_HDR_FLAG_READONLY) {
 866                 ERROR("Cannot modify \"%"TS"\": is marked read-only",
 867                       wim->filename);
 868                 return WIMLIB_ERR_WIM_IS_READONLY;
 869         }
 870         return 0;
 871 }
 872
 873 /* API function documented in wimlib.h  */
 874 WIMLIBAPI void
 875 wimlib_free(WIMStruct *wim)
 876 {
 877         if (!wim)
 878                 return;
 879
 880         while (!list_empty(&wim->subwims)) {
 881                 WIMStruct *subwim;
 882
 883                 subwim = list_entry(wim->subwims.next, WIMStruct, subwim_node);
 884                 list_del(&subwim->subwim_node);
 885                 wimlib_free(subwim);
 886         }
 887
 888         if (filedes_valid(&wim->in_fd))
 889                 filedes_close(&wim->in_fd);
 890         if (filedes_valid(&wim->out_fd))
 891                 filedes_close(&wim->out_fd);
 892
 893         free_lookup_table(wim->lookup_table);
 894
 895         wimlib_free_decompressor(wim->decompressor);
 896
 897         FREE(wim->filename);
 898         free_wim_info(wim->wim_info);
 899         if (wim->image_metadata) {
 900                 for (unsigned i = 0; i < wim->hdr.image_count; i++)
 901                         put_image_metadata(wim->image_metadata[i], NULL);
 902                 FREE(wim->image_metadata);
 903         }
 904         FREE(wim);
 905 }
 906
 907 static bool
 908 test_locale_ctype_utf8(void)
 909 {
 910 #ifdef __WIN32__
 911         return false;
 912 #else
 913         char *ctype = nl_langinfo(CODESET);
 914
 915         return (!strstr(ctype, "UTF-8") ||
 916                 !strstr(ctype, "UTF8") ||
 917                 !strstr(ctype, "utf8") ||
 918                 !strstr(ctype, "utf-8"));
 919 #endif
 920 }
 921
 922 /* API function documented in wimlib.h  */
 923 WIMLIBAPI u32
 924 wimlib_get_version(void)
 925 {
 926         return (WIMLIB_MAJOR_VERSION << 20) |
 927                (WIMLIB_MINOR_VERSION << 10) |
 928                 WIMLIB_PATCH_VERSION;
 929 }
 930
 931 static bool lib_initialized = false;
 932
 933 /* API function documented in wimlib.h  */
 934 WIMLIBAPI int
 935 wimlib_global_init(int init_flags)
 936 {
 937         if (lib_initialized)
 938                 return 0;
 939
 940 #ifdef ENABLE_ERROR_MESSAGES
 941         if (!wimlib_error_file)
 942                 wimlib_error_file = stderr;
 943 #endif
 944
 945         if (init_flags & ~(WIMLIB_INIT_FLAG_ASSUME_UTF8 |
 946                            WIMLIB_INIT_FLAG_DONT_ACQUIRE_PRIVILEGES |
 947                            WIMLIB_INIT_FLAG_STRICT_CAPTURE_PRIVILEGES |
 948                            WIMLIB_INIT_FLAG_STRICT_APPLY_PRIVILEGES |
 949                            WIMLIB_INIT_FLAG_DEFAULT_CASE_SENSITIVE |
 950                            WIMLIB_INIT_FLAG_DEFAULT_CASE_INSENSITIVE))
 951                 return WIMLIB_ERR_INVALID_PARAM;
 952
 953         libxml_global_init();
 954         if (!(init_flags & WIMLIB_INIT_FLAG_ASSUME_UTF8)) {
 955                 wimlib_mbs_is_utf8 = test_locale_ctype_utf8();
 956         #ifdef WITH_NTFS_3G
 957                 if (!wimlib_mbs_is_utf8)
 958                         libntfs3g_global_init();
 959         #endif
 960         }
 961 #ifdef __WIN32__
 962         {
 963                 int ret = win32_global_init(init_flags);
 964                 if (ret)
 965                         return ret;
 966         }
 967 #endif
 968         iconv_global_init();
 969         init_upcase();
 970         if (init_flags & WIMLIB_INIT_FLAG_DEFAULT_CASE_SENSITIVE)
 971                 default_ignore_case = false;
 972         else if (init_flags & WIMLIB_INIT_FLAG_DEFAULT_CASE_INSENSITIVE)
 973                 default_ignore_case = true;
 974         lib_initialized = true;
 975         return 0;
 976 }
 977
 978 /* API function documented in wimlib.h  */
 979 WIMLIBAPI void
 980 wimlib_global_cleanup(void)
 981 {
 982         if (!lib_initialized)
 983                 return;
 984         libxml_global_cleanup();
 985         iconv_global_cleanup();
 986 #ifdef __WIN32__
 987         win32_global_cleanup();
 988 #endif
 989
 990         wimlib_set_error_file(NULL);
 991         lib_initialized = false;
 992 }