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   1 /*
   2  * wim.c - High-level code dealing with WIMStructs and images.
   3  */
   4
   5 /*
   6  * Copyright (C) 2012-2016 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 #include <pthread.h>
  29 #include <stdlib.h>
  30 #include <unistd.h>
  31
  32 #include "wimlib.h"
  33 #include "wimlib/assert.h"
  34 #include "wimlib/blob_table.h"
  35 #include "wimlib/dentry.h"
  36 #include "wimlib/encoding.h"
  37 #include "wimlib/file_io.h"
  38 #include "wimlib/integrity.h"
  39 #include "wimlib/metadata.h"
  40 #include "wimlib/security.h"
  41 #include "wimlib/wim.h"
  42 #include "wimlib/xml.h"
  43 #include "wimlib/win32.h"
  44
  45 /* Information about the available compression types for the WIM format.  */
  46 static const struct {
  47         const tchar *name;
  48         u32 min_chunk_size;
  49         u32 max_chunk_size;
  50         u32 default_nonsolid_chunk_size;
  51         u32 default_solid_chunk_size;
  52 } wim_ctype_info[] = {
  53         [WIMLIB_COMPRESSION_TYPE_NONE] = {
  54                 .name = T("None"),
  55                 .min_chunk_size = 0,
  56                 .max_chunk_size = 0,
  57                 .default_nonsolid_chunk_size = 0,
  58                 .default_solid_chunk_size = 0,
  59         },
  60         [WIMLIB_COMPRESSION_TYPE_XPRESS] = {
  61                 .name = T("XPRESS"),
  62                 .min_chunk_size = 4096,
  63                 .max_chunk_size = 65536,
  64                 .default_nonsolid_chunk_size = 32768,
  65                 .default_solid_chunk_size = 32768,
  66         },
  67         [WIMLIB_COMPRESSION_TYPE_LZX] = {
  68                 .name = T("LZX"),
  69                 .min_chunk_size = 32768,
  70                 .max_chunk_size = 2097152,
  71                 .default_nonsolid_chunk_size = 32768,
  72                 .default_solid_chunk_size = 32768,
  73         },
  74         [WIMLIB_COMPRESSION_TYPE_LZMS] = {
  75                 .name = T("LZMS"),
  76                 .min_chunk_size = 32768,
  77                 .max_chunk_size = 1073741824,
  78                 .default_nonsolid_chunk_size = 131072,
  79                 .default_solid_chunk_size = 67108864,
  80         },
  81 };
  82
  83 /* Is the specified compression type valid?  */
  84 static bool
  85 wim_compression_type_valid(enum wimlib_compression_type ctype)
  86 {
  87         return (unsigned)ctype < ARRAY_LEN(wim_ctype_info) &&
  88                wim_ctype_info[(unsigned)ctype].name != NULL;
  89 }
  90
  91 /* Is the specified chunk size valid for the compression type?  */
  92 static bool
  93 wim_chunk_size_valid(u32 chunk_size, enum wimlib_compression_type ctype)
  94 {
  95         if (!(chunk_size == 0 || is_power_of_2(chunk_size)))
  96                 return false;
  97
  98         return chunk_size >= wim_ctype_info[(unsigned)ctype].min_chunk_size &&
  99                chunk_size <= wim_ctype_info[(unsigned)ctype].max_chunk_size;
 100 }
 101
 102 /* Return the default chunk size to use for the specified compression type in
 103  * non-solid resources.  */
 104 static u32
 105 wim_default_nonsolid_chunk_size(enum wimlib_compression_type ctype)
 106 {
 107         return wim_ctype_info[(unsigned)ctype].default_nonsolid_chunk_size;
 108 }
 109
 110 /* Return the default chunk size to use for the specified compression type in
 111  * solid resources.  */
 112 static u32
 113 wim_default_solid_chunk_size(enum wimlib_compression_type ctype)
 114 {
 115         return wim_ctype_info[(unsigned)ctype].default_solid_chunk_size;
 116 }
 117
 118 /* Return the default compression type to use in solid resources.  */
 119 static enum wimlib_compression_type
 120 wim_default_solid_compression_type(void)
 121 {
 122         return WIMLIB_COMPRESSION_TYPE_LZMS;
 123 }
 124
 125 static int
 126 is_blob_in_solid_resource(struct blob_descriptor *blob, void *_ignore)
 127 {
 128         return blob->blob_location == BLOB_IN_WIM &&
 129                 (blob->rdesc->flags & WIM_RESHDR_FLAG_SOLID);
 130 }
 131
 132 bool
 133 wim_has_solid_resources(const WIMStruct *wim)
 134 {
 135         return for_blob_in_table(wim->blob_table, is_blob_in_solid_resource, NULL);
 136 }
 137
 138 static WIMStruct *
 139 new_wim_struct(void)
 140 {
 141         WIMStruct *wim = CALLOC(1, sizeof(WIMStruct));
 142         if (!wim)
 143                 return NULL;
 144
 145         wim->refcnt = 1;
 146         filedes_invalidate(&wim->in_fd);
 147         filedes_invalidate(&wim->out_fd);
 148         wim->out_solid_compression_type = wim_default_solid_compression_type();
 149         wim->out_solid_chunk_size = wim_default_solid_chunk_size(
 150                                         wim->out_solid_compression_type);
 151         return wim;
 152 }
 153
 154 /* API function documented in wimlib.h  */
 155 WIMLIBAPI int
 156 wimlib_create_new_wim(enum wimlib_compression_type ctype, WIMStruct **wim_ret)
 157 {
 158         int ret;
 159         WIMStruct *wim;
 160
 161         ret = wimlib_global_init(0);
 162         if (ret)
 163                 return ret;
 164
 165         if (!wim_ret)
 166                 return WIMLIB_ERR_INVALID_PARAM;
 167
 168         if (!wim_compression_type_valid(ctype))
 169                 return WIMLIB_ERR_INVALID_COMPRESSION_TYPE;
 170
 171         wim = new_wim_struct();
 172         if (!wim)
 173                 return WIMLIB_ERR_NOMEM;
 174
 175         /* Fill in wim->hdr with default values */
 176         wim->hdr.magic = WIM_MAGIC;
 177         wim->hdr.wim_version = WIM_VERSION_DEFAULT;
 178         wim->hdr.part_number = 1;
 179         wim->hdr.total_parts = 1;
 180         wim->compression_type = WIMLIB_COMPRESSION_TYPE_NONE;
 181
 182         /* Set the output compression type */
 183         wim->out_compression_type = ctype;
 184         wim->out_chunk_size = wim_default_nonsolid_chunk_size(ctype);
 185
 186         /* Allocate an empty XML info and blob table */
 187         wim->xml_info = xml_new_info_struct();
 188         wim->blob_table = new_blob_table(64);
 189         if (!wim->xml_info || !wim->blob_table) {
 190                 wimlib_free(wim);
 191                 return WIMLIB_ERR_NOMEM;
 192         }
 193
 194         *wim_ret = wim;
 195         return 0;
 196 }
 197
 198 static void
 199 unload_image_metadata(struct wim_image_metadata *imd)
 200 {
 201         free_dentry_tree(imd->root_dentry, NULL);
 202         imd->root_dentry = NULL;
 203         free_wim_security_data(imd->security_data);
 204         imd->security_data = NULL;
 205         INIT_HLIST_HEAD(&imd->inode_list);
 206 }
 207
 208 /* Release a reference to the specified image metadata.  This assumes that no
 209  * WIMStruct has the image selected.  */
 210 void
 211 put_image_metadata(struct wim_image_metadata *imd)
 212 {
 213         struct blob_descriptor *blob, *tmp;
 214
 215         if (!imd)
 216                 return;
 217         wimlib_assert(imd->refcnt > 0);
 218         if (--imd->refcnt != 0)
 219                 return;
 220         wimlib_assert(imd->selected_refcnt == 0);
 221         unload_image_metadata(imd);
 222         list_for_each_entry_safe(blob, tmp, &imd->unhashed_blobs, unhashed_list)
 223                 free_blob_descriptor(blob);
 224         free_blob_descriptor(imd->metadata_blob);
 225         FREE(imd);
 226 }
 227
 228 /* Appends the specified image metadata structure to the array of image metadata
 229  * for a WIM, and increments the image count. */
 230 int
 231 append_image_metadata(WIMStruct *wim, struct wim_image_metadata *imd)
 232 {
 233         struct wim_image_metadata **imd_array;
 234
 235         if (!wim_has_metadata(wim))
 236                 return WIMLIB_ERR_METADATA_NOT_FOUND;
 237
 238         if (wim->hdr.image_count >= MAX_IMAGES)
 239                 return WIMLIB_ERR_IMAGE_COUNT;
 240
 241         imd_array = REALLOC(wim->image_metadata,
 242                             sizeof(wim->image_metadata[0]) * (wim->hdr.image_count + 1));
 243
 244         if (!imd_array)
 245                 return WIMLIB_ERR_NOMEM;
 246         wim->image_metadata = imd_array;
 247         imd_array[wim->hdr.image_count++] = imd;
 248         return 0;
 249 }
 250
 251 static struct wim_image_metadata *
 252 new_image_metadata(struct blob_descriptor *metadata_blob,
 253                    struct wim_security_data *security_data)
 254 {
 255         struct wim_image_metadata *imd;
 256
 257         imd = CALLOC(1, sizeof(*imd));
 258         if (!imd)
 259                 return NULL;
 260
 261         metadata_blob->is_metadata = 1;
 262         imd->refcnt = 1;
 263         imd->selected_refcnt = 0;
 264         imd->root_dentry = NULL;
 265         imd->security_data = security_data;
 266         imd->metadata_blob = metadata_blob;
 267         INIT_HLIST_HEAD(&imd->inode_list);
 268         INIT_LIST_HEAD(&imd->unhashed_blobs);
 269         imd->stats_outdated = false;
 270         return imd;
 271 }
 272
 273 /* Create an image metadata structure for a new empty image.  */
 274 struct wim_image_metadata *
 275 new_empty_image_metadata(void)
 276 {
 277         struct blob_descriptor *metadata_blob;
 278         struct wim_security_data *security_data;
 279         struct wim_image_metadata *imd;
 280
 281         metadata_blob = new_blob_descriptor();
 282         security_data = new_wim_security_data();
 283         if (metadata_blob && security_data) {
 284                 metadata_blob->refcnt = 1;
 285                 imd = new_image_metadata(metadata_blob, security_data);
 286                 if (imd)
 287                         return imd;
 288         }
 289         free_blob_descriptor(metadata_blob);
 290         FREE(security_data);
 291         return NULL;
 292 }
 293
 294 /* Create an image metadata structure that refers to the specified metadata
 295  * resource and is initially not loaded.  */
 296 struct wim_image_metadata *
 297 new_unloaded_image_metadata(struct blob_descriptor *metadata_blob)
 298 {
 299         wimlib_assert(metadata_blob->blob_location == BLOB_IN_WIM);
 300         return new_image_metadata(metadata_blob, NULL);
 301 }
 302
 303 /*
 304  * Load the metadata for the specified WIM image into memory and set it
 305  * as the WIMStruct's currently selected image.
 306  *
 307  * @wim
 308  *      The WIMStruct for the WIM.
 309  * @image
 310  *      The 1-based index of the image in the WIM to select.
 311  *
 312  * On success, 0 will be returned, wim->current_image will be set to
 313  * @image, and wim_get_current_image_metadata() can be used to retrieve
 314  * metadata information for the image.
 315  *
 316  * On failure, WIMLIB_ERR_INVALID_IMAGE, WIMLIB_ERR_METADATA_NOT_FOUND,
 317  * or another error code will be returned.
 318  */
 319 int
 320 select_wim_image(WIMStruct *wim, int image)
 321 {
 322         struct wim_image_metadata *imd;
 323         int ret;
 324
 325         if (image == WIMLIB_NO_IMAGE)
 326                 return WIMLIB_ERR_INVALID_IMAGE;
 327
 328         if (image == wim->current_image)
 329                 return 0;
 330
 331         if (image < 1 || image > wim->hdr.image_count)
 332                 return WIMLIB_ERR_INVALID_IMAGE;
 333
 334         if (!wim_has_metadata(wim))
 335                 return WIMLIB_ERR_METADATA_NOT_FOUND;
 336
 337         deselect_current_wim_image(wim);
 338
 339         imd = wim->image_metadata[image - 1];
 340         if (!is_image_loaded(imd)) {
 341                 ret = read_metadata_resource(imd);
 342                 if (ret)
 343                         return ret;
 344         }
 345         wim->current_image = image;
 346         imd->selected_refcnt++;
 347         return 0;
 348 }
 349
 350 /*
 351  * Deselect the WIMStruct's currently selected image, if any.  To reduce memory
 352  * usage, possibly unload the newly deselected image's metadata from memory.
 353  */
 354 void
 355 deselect_current_wim_image(WIMStruct *wim)
 356 {
 357         struct wim_image_metadata *imd;
 358
 359         if (wim->current_image == WIMLIB_NO_IMAGE)
 360                 return;
 361         imd = wim_get_current_image_metadata(wim);
 362         wimlib_assert(imd->selected_refcnt > 0);
 363         imd->selected_refcnt--;
 364         wim->current_image = WIMLIB_NO_IMAGE;
 365
 366         if (can_unload_image(imd)) {
 367                 wimlib_assert(list_empty(&imd->unhashed_blobs));
 368                 unload_image_metadata(imd);
 369         }
 370 }
 371
 372 /*
 373  * Calls a function on images in the WIM.  If @image is WIMLIB_ALL_IMAGES,
 374  * @visitor is called on the WIM once for each image, with each image selected
 375  * as the current image in turn.  If @image is a certain image, @visitor is
 376  * called on the WIM only once, with that image selected.
 377  */
 378 int
 379 for_image(WIMStruct *wim, int image, int (*visitor)(WIMStruct *))
 380 {
 381         int ret;
 382         int start;
 383         int end;
 384         int i;
 385
 386         if (image == WIMLIB_ALL_IMAGES) {
 387                 start = 1;
 388                 end = wim->hdr.image_count;
 389         } else if (image >= 1 && image <= wim->hdr.image_count) {
 390                 start = image;
 391                 end = image;
 392         } else {
 393                 return WIMLIB_ERR_INVALID_IMAGE;
 394         }
 395         for (i = start; i <= end; i++) {
 396                 ret = select_wim_image(wim, i);
 397                 if (ret != 0)
 398                         return ret;
 399                 ret = visitor(wim);
 400                 if (ret != 0)
 401                         return ret;
 402         }
 403         return 0;
 404 }
 405
 406 /* API function documented in wimlib.h  */
 407 WIMLIBAPI int
 408 wimlib_resolve_image(WIMStruct *wim, const tchar *image_name_or_num)
 409 {
 410         tchar *p;
 411         long image;
 412         int i;
 413
 414         if (!image_name_or_num || !*image_name_or_num)
 415                 return WIMLIB_NO_IMAGE;
 416
 417         if (!tstrcasecmp(image_name_or_num, T("all"))
 418             || !tstrcasecmp(image_name_or_num, T("*")))
 419                 return WIMLIB_ALL_IMAGES;
 420         image = tstrtol(image_name_or_num, &p, 10);
 421         if (p != image_name_or_num && *p == T('\0') && image > 0) {
 422                 if (image > wim->hdr.image_count)
 423                         return WIMLIB_NO_IMAGE;
 424                 return image;
 425         } else {
 426                 for (i = 1; i <= wim->hdr.image_count; i++) {
 427                         if (!tstrcmp(image_name_or_num,
 428                                      wimlib_get_image_name(wim, i)))
 429                                 return i;
 430                 }
 431                 return WIMLIB_NO_IMAGE;
 432         }
 433 }
 434
 435 /* API function documented in wimlib.h  */
 436 WIMLIBAPI void
 437 wimlib_print_available_images(const WIMStruct *wim, int image)
 438 {
 439         int first;
 440         int last;
 441         int i;
 442         int n;
 443         if (image == WIMLIB_ALL_IMAGES) {
 444                 n = tprintf(T("Available Images:\n"));
 445                 first = 1;
 446                 last = wim->hdr.image_count;
 447         } else if (image >= 1 && image <= wim->hdr.image_count) {
 448                 n = tprintf(T("Information for Image %d\n"), image);
 449                 first = image;
 450                 last = image;
 451         } else {
 452                 tprintf(T("wimlib_print_available_images(): Invalid image %d"),
 453                         image);
 454                 return;
 455         }
 456         for (i = 0; i < n - 1; i++)
 457                 tputchar(T('-'));
 458         tputchar(T('\n'));
 459         for (i = first; i <= last; i++)
 460                 xml_print_image_info(wim->xml_info, i);
 461 }
 462
 463 /* API function documented in wimlib.h  */
 464 WIMLIBAPI int
 465 wimlib_get_wim_info(WIMStruct *wim, struct wimlib_wim_info *info)
 466 {
 467         memset(info, 0, sizeof(struct wimlib_wim_info));
 468         copy_guid(info->guid, wim->hdr.guid);
 469         info->image_count = wim->hdr.image_count;
 470         info->boot_index = wim->hdr.boot_idx;
 471         info->wim_version = wim->hdr.wim_version;
 472         info->chunk_size = wim->chunk_size;
 473         info->part_number = wim->hdr.part_number;
 474         info->total_parts = wim->hdr.total_parts;
 475         info->compression_type = wim->compression_type;
 476         info->total_bytes = xml_get_total_bytes(wim->xml_info);
 477         info->has_integrity_table = wim_has_integrity_table(wim);
 478         info->opened_from_file = (wim->filename != NULL);
 479         info->is_readonly = (wim->hdr.flags & WIM_HDR_FLAG_READONLY) ||
 480                              (wim->hdr.total_parts != 1) ||
 481                              (wim->filename && taccess(wim->filename, W_OK));
 482         info->has_rpfix = (wim->hdr.flags & WIM_HDR_FLAG_RP_FIX) != 0;
 483         info->is_marked_readonly = (wim->hdr.flags & WIM_HDR_FLAG_READONLY) != 0;
 484         info->write_in_progress = (wim->hdr.flags & WIM_HDR_FLAG_WRITE_IN_PROGRESS) != 0;
 485         info->metadata_only = (wim->hdr.flags & WIM_HDR_FLAG_METADATA_ONLY) != 0;
 486         info->resource_only = (wim->hdr.flags & WIM_HDR_FLAG_RESOURCE_ONLY) != 0;
 487         info->spanned = (wim->hdr.flags & WIM_HDR_FLAG_SPANNED) != 0;
 488         info->pipable = wim_is_pipable(wim);
 489         return 0;
 490 }
 491
 492 /* API function documented in wimlib.h  */
 493 WIMLIBAPI int
 494 wimlib_set_wim_info(WIMStruct *wim, const struct wimlib_wim_info *info, int which)
 495 {
 496         if (which & ~(WIMLIB_CHANGE_READONLY_FLAG |
 497                       WIMLIB_CHANGE_GUID |
 498                       WIMLIB_CHANGE_BOOT_INDEX |
 499                       WIMLIB_CHANGE_RPFIX_FLAG))
 500                 return WIMLIB_ERR_INVALID_PARAM;
 501
 502         if ((which & WIMLIB_CHANGE_BOOT_INDEX) &&
 503             info->boot_index > wim->hdr.image_count)
 504                 return WIMLIB_ERR_INVALID_IMAGE;
 505
 506         if (which & WIMLIB_CHANGE_READONLY_FLAG) {
 507                 if (info->is_marked_readonly)
 508                         wim->hdr.flags |= WIM_HDR_FLAG_READONLY;
 509                 else
 510                         wim->hdr.flags &= ~WIM_HDR_FLAG_READONLY;
 511         }
 512
 513         if (which & WIMLIB_CHANGE_GUID)
 514                 copy_guid(wim->hdr.guid, info->guid);
 515
 516         if (which & WIMLIB_CHANGE_BOOT_INDEX)
 517                 wim->hdr.boot_idx = info->boot_index;
 518
 519         if (which & WIMLIB_CHANGE_RPFIX_FLAG) {
 520                 if (info->has_rpfix)
 521                         wim->hdr.flags |= WIM_HDR_FLAG_RP_FIX;
 522                 else
 523                         wim->hdr.flags &= ~WIM_HDR_FLAG_RP_FIX;
 524         }
 525         return 0;
 526 }
 527
 528 /* API function documented in wimlib.h  */
 529 WIMLIBAPI int
 530 wimlib_set_output_compression_type(WIMStruct *wim,
 531                                    enum wimlib_compression_type ctype)
 532 {
 533         if (!wim_compression_type_valid(ctype))
 534                 return WIMLIB_ERR_INVALID_COMPRESSION_TYPE;
 535
 536         wim->out_compression_type = ctype;
 537
 538         /* Reset the chunk size if it's no longer valid.  */
 539         if (!wim_chunk_size_valid(wim->out_chunk_size, ctype))
 540                 wim->out_chunk_size = wim_default_nonsolid_chunk_size(ctype);
 541         return 0;
 542 }
 543
 544 /* API function documented in wimlib.h  */
 545 WIMLIBAPI int
 546 wimlib_set_output_pack_compression_type(WIMStruct *wim,
 547                                         enum wimlib_compression_type ctype)
 548 {
 549         if (!wim_compression_type_valid(ctype))
 550                 return WIMLIB_ERR_INVALID_COMPRESSION_TYPE;
 551
 552         /* Solid resources can't be uncompressed.  */
 553         if (ctype == WIMLIB_COMPRESSION_TYPE_NONE)
 554                 return WIMLIB_ERR_INVALID_COMPRESSION_TYPE;
 555
 556         wim->out_solid_compression_type = ctype;
 557
 558         /* Reset the chunk size if it's no longer valid.  */
 559         if (!wim_chunk_size_valid(wim->out_solid_chunk_size, ctype))
 560                 wim->out_solid_chunk_size = wim_default_solid_chunk_size(ctype);
 561         return 0;
 562 }
 563
 564 /* API function documented in wimlib.h  */
 565 WIMLIBAPI int
 566 wimlib_set_output_chunk_size(WIMStruct *wim, u32 chunk_size)
 567 {
 568         if (chunk_size == 0) {
 569                 wim->out_chunk_size =
 570                         wim_default_nonsolid_chunk_size(wim->out_compression_type);
 571                 return 0;
 572         }
 573
 574         if (!wim_chunk_size_valid(chunk_size, wim->out_compression_type))
 575                 return WIMLIB_ERR_INVALID_CHUNK_SIZE;
 576
 577         wim->out_chunk_size = chunk_size;
 578         return 0;
 579 }
 580
 581 /* API function documented in wimlib.h  */
 582 WIMLIBAPI int
 583 wimlib_set_output_pack_chunk_size(WIMStruct *wim, u32 chunk_size)
 584 {
 585         if (chunk_size == 0) {
 586                 wim->out_solid_chunk_size =
 587                         wim_default_solid_chunk_size(wim->out_solid_compression_type);
 588                 return 0;
 589         }
 590
 591         if (!wim_chunk_size_valid(chunk_size, wim->out_solid_compression_type))
 592                 return WIMLIB_ERR_INVALID_CHUNK_SIZE;
 593
 594         wim->out_solid_chunk_size = chunk_size;
 595         return 0;
 596 }
 597
 598 /* API function documented in wimlib.h  */
 599 WIMLIBAPI const tchar *
 600 wimlib_get_compression_type_string(enum wimlib_compression_type ctype)
 601 {
 602         if (!wim_compression_type_valid(ctype))
 603                 return T("Invalid");
 604
 605         return wim_ctype_info[(unsigned)ctype].name;
 606 }
 607
 608 WIMLIBAPI void
 609 wimlib_register_progress_function(WIMStruct *wim,
 610                                   wimlib_progress_func_t progfunc,
 611                                   void *progctx)
 612 {
 613         wim->progfunc = progfunc;
 614         wim->progctx = progctx;
 615 }
 616
 617 static int
 618 open_wim_file(const tchar *filename, struct filedes *fd_ret)
 619 {
 620         int raw_fd;
 621
 622         raw_fd = topen(filename, O_RDONLY | O_BINARY);
 623         if (raw_fd < 0) {
 624                 ERROR_WITH_ERRNO("Can't open \"%"TS"\" read-only", filename);
 625                 return WIMLIB_ERR_OPEN;
 626         }
 627         filedes_init(fd_ret, raw_fd);
 628         return 0;
 629 }
 630
 631 /*
 632  * Begins the reading of a WIM file; opens the file and reads its header and
 633  * blob table, and optionally checks the integrity.
 634  */
 635 static int
 636 begin_read(WIMStruct *wim, const void *wim_filename_or_fd, int open_flags)
 637 {
 638         int ret;
 639         const tchar *wimfile;
 640
 641         if (open_flags & WIMLIB_OPEN_FLAG_FROM_PIPE) {
 642                 wimfile = NULL;
 643                 filedes_init(&wim->in_fd, *(const int*)wim_filename_or_fd);
 644                 wim->in_fd.is_pipe = 1;
 645         } else {
 646                 wimfile = wim_filename_or_fd;
 647                 ret = open_wim_file(wimfile, &wim->in_fd);
 648                 if (ret)
 649                         return ret;
 650
 651                 /* The absolute path to the WIM is requested so that
 652                  * wimlib_overwrite() still works even if the process changes
 653                  * its working directory.  This actually happens if a WIM is
 654                  * mounted read-write, since the FUSE thread changes directory
 655                  * to "/", and it needs to be able to find the WIM file again.
 656                  *
 657                  * This will break if the full path to the WIM changes in the
 658                  * intervening time...
 659                  *
 660                  * Warning: in Windows native builds, realpath() calls the
 661                  * replacement function in win32_replacements.c.
 662                  */
 663                 wim->filename = realpath(wimfile, NULL);
 664                 if (!wim->filename) {
 665                         ERROR_WITH_ERRNO("Failed to get full path to file "
 666                                          "\"%"TS"\"", wimfile);
 667                         if (errno == ENOMEM)
 668                                 return WIMLIB_ERR_NOMEM;
 669                         else
 670                                 return WIMLIB_ERR_NO_FILENAME;
 671                 }
 672         }
 673
 674         ret = read_wim_header(wim, &wim->hdr);
 675         if (ret)
 676                 return ret;
 677
 678         if (wim->hdr.flags & WIM_HDR_FLAG_WRITE_IN_PROGRESS) {
 679                 WARNING("The WIM_HDR_FLAG_WRITE_IN_PROGRESS flag is set in the header of\n"
 680                         "          \"%"TS"\".  It may be being changed by another process,\n"
 681                         "          or a process may have crashed while writing the WIM.",
 682                         wimfile);
 683         }
 684
 685         if (open_flags & WIMLIB_OPEN_FLAG_WRITE_ACCESS) {
 686                 ret = can_modify_wim(wim);
 687                 if (ret)
 688                         return ret;
 689         }
 690
 691         if ((open_flags & WIMLIB_OPEN_FLAG_ERROR_IF_SPLIT) &&
 692             (wim->hdr.total_parts != 1))
 693                 return WIMLIB_ERR_IS_SPLIT_WIM;
 694
 695         /* If the boot index is invalid, print a warning and set it to 0 */
 696         if (wim->hdr.boot_idx > wim->hdr.image_count) {
 697                 WARNING("Ignoring invalid boot index.");
 698                 wim->hdr.boot_idx = 0;
 699         }
 700
 701         /* Check and cache the compression type */
 702         if (wim->hdr.flags & WIM_HDR_FLAG_COMPRESSION) {
 703                 if (wim->hdr.flags & WIM_HDR_FLAG_COMPRESS_LZX) {
 704                         wim->compression_type = WIMLIB_COMPRESSION_TYPE_LZX;
 705                 } else if (wim->hdr.flags & (WIM_HDR_FLAG_COMPRESS_XPRESS |
 706                                              WIM_HDR_FLAG_COMPRESS_XPRESS_2)) {
 707                         wim->compression_type = WIMLIB_COMPRESSION_TYPE_XPRESS;
 708                 } else if (wim->hdr.flags & WIM_HDR_FLAG_COMPRESS_LZMS) {
 709                         wim->compression_type = WIMLIB_COMPRESSION_TYPE_LZMS;
 710                 } else {
 711                         return WIMLIB_ERR_INVALID_COMPRESSION_TYPE;
 712                 }
 713         } else {
 714                 wim->compression_type = WIMLIB_COMPRESSION_TYPE_NONE;
 715         }
 716         wim->out_compression_type = wim->compression_type;
 717
 718         /* Check and cache the chunk size.  */
 719         wim->chunk_size = wim->hdr.chunk_size;
 720         wim->out_chunk_size = wim->chunk_size;
 721         if (!wim_chunk_size_valid(wim->chunk_size, wim->compression_type)) {
 722                 ERROR("Invalid chunk size (%"PRIu32" bytes) "
 723                       "for compression type %"TS"!", wim->chunk_size,
 724                       wimlib_get_compression_type_string(wim->compression_type));
 725                 return WIMLIB_ERR_INVALID_CHUNK_SIZE;
 726         }
 727
 728         if (open_flags & WIMLIB_OPEN_FLAG_CHECK_INTEGRITY) {
 729                 ret = check_wim_integrity(wim);
 730                 if (ret == WIM_INTEGRITY_NONEXISTENT) {
 731                         WARNING("\"%"TS"\" does not contain integrity "
 732                                 "information.  Skipping integrity check.",
 733                                 wimfile);
 734                 } else if (ret == WIM_INTEGRITY_NOT_OK) {
 735                         return WIMLIB_ERR_INTEGRITY;
 736                 } else if (ret != WIM_INTEGRITY_OK) {
 737                         return ret;
 738                 }
 739         }
 740
 741         if (wim->hdr.image_count != 0 && wim->hdr.part_number == 1) {
 742                 wim->image_metadata = CALLOC(wim->hdr.image_count,
 743                                              sizeof(wim->image_metadata[0]));
 744                 if (!wim->image_metadata)
 745                         return WIMLIB_ERR_NOMEM;
 746         }
 747
 748         if (open_flags & WIMLIB_OPEN_FLAG_FROM_PIPE) {
 749                 wim->blob_table = new_blob_table(64);
 750                 if (!wim->blob_table)
 751                         return WIMLIB_ERR_NOMEM;
 752         } else {
 753                 if (wim->hdr.blob_table_reshdr.uncompressed_size == 0 &&
 754                     wim->hdr.xml_data_reshdr.uncompressed_size == 0)
 755                         return WIMLIB_ERR_WIM_IS_INCOMPLETE;
 756
 757                 ret = read_wim_xml_data(wim);
 758                 if (ret)
 759                         return ret;
 760
 761                 if (xml_get_image_count(wim->xml_info) != wim->hdr.image_count) {
 762                         ERROR("The WIM's header is inconsistent with its XML data.\n"
 763                               "        Please submit a bug report if you believe this "
 764                               "WIM file should be considered valid.");
 765                         return WIMLIB_ERR_IMAGE_COUNT;
 766                 }
 767
 768                 ret = read_blob_table(wim);
 769                 if (ret)
 770                         return ret;
 771         }
 772         return 0;
 773 }
 774
 775 int
 776 open_wim_as_WIMStruct(const void *wim_filename_or_fd, int open_flags,
 777                       WIMStruct **wim_ret,
 778                       wimlib_progress_func_t progfunc, void *progctx)
 779 {
 780         WIMStruct *wim;
 781         int ret;
 782
 783         ret = wimlib_global_init(0);
 784         if (ret)
 785                 return ret;
 786
 787         wim = new_wim_struct();
 788         if (!wim)
 789                 return WIMLIB_ERR_NOMEM;
 790
 791         wim->progfunc = progfunc;
 792         wim->progctx = progctx;
 793
 794         ret = begin_read(wim, wim_filename_or_fd, open_flags);
 795         if (ret) {
 796                 wimlib_free(wim);
 797                 return ret;
 798         }
 799
 800         *wim_ret = wim;
 801         return 0;
 802 }
 803
 804 /* API function documented in wimlib.h  */
 805 WIMLIBAPI int
 806 wimlib_open_wim_with_progress(const tchar *wimfile, int open_flags,
 807                               WIMStruct **wim_ret,
 808                               wimlib_progress_func_t progfunc, void *progctx)
 809 {
 810         if (open_flags & ~(WIMLIB_OPEN_FLAG_CHECK_INTEGRITY |
 811                            WIMLIB_OPEN_FLAG_ERROR_IF_SPLIT |
 812                            WIMLIB_OPEN_FLAG_WRITE_ACCESS))
 813                 return WIMLIB_ERR_INVALID_PARAM;
 814
 815         if (!wimfile || !*wimfile || !wim_ret)
 816                 return WIMLIB_ERR_INVALID_PARAM;
 817
 818         return open_wim_as_WIMStruct(wimfile, open_flags, wim_ret,
 819                                      progfunc, progctx);
 820 }
 821
 822 /* API function documented in wimlib.h  */
 823 WIMLIBAPI int
 824 wimlib_open_wim(const tchar *wimfile, int open_flags, WIMStruct **wim_ret)
 825 {
 826         return wimlib_open_wim_with_progress(wimfile, open_flags, wim_ret,
 827                                              NULL, NULL);
 828 }
 829
 830 /* Checksum all blobs that are unhashed (other than the metadata blobs), merging
 831  * them into the blob table as needed.  This is a no-op unless files have been
 832  * added to an image in the same WIMStruct.  */
 833 int
 834 wim_checksum_unhashed_blobs(WIMStruct *wim)
 835 {
 836         int ret;
 837
 838         if (!wim_has_metadata(wim))
 839                 return 0;
 840         for (int i = 0; i < wim->hdr.image_count; i++) {
 841                 struct blob_descriptor *blob, *tmp;
 842                 struct wim_image_metadata *imd = wim->image_metadata[i];
 843                 image_for_each_unhashed_blob_safe(blob, tmp, imd) {
 844                         struct blob_descriptor *new_blob;
 845                         ret = hash_unhashed_blob(blob, wim->blob_table, &new_blob);
 846                         if (ret)
 847                                 return ret;
 848                         if (new_blob != blob)
 849                                 free_blob_descriptor(blob);
 850                 }
 851         }
 852         return 0;
 853 }
 854
 855 /*
 856  * can_modify_wim - Check if a given WIM is writeable.  This is only the case if
 857  * it meets the following three conditions:
 858  *
 859  * 1. Write access is allowed to the underlying file (if any) at the filesystem level.
 860  * 2. The WIM is not part of a spanned set.
 861  * 3. The WIM_HDR_FLAG_READONLY flag is not set in the WIM header.
 862  *
 863  * Return value is 0 if writable; WIMLIB_ERR_WIM_IS_READONLY otherwise.
 864  */
 865 int
 866 can_modify_wim(WIMStruct *wim)
 867 {
 868         if (wim->filename) {
 869                 if (taccess(wim->filename, W_OK)) {
 870                         ERROR_WITH_ERRNO("Can't modify \"%"TS"\"", wim->filename);
 871                         return WIMLIB_ERR_WIM_IS_READONLY;
 872                 }
 873         }
 874         if (wim->hdr.total_parts != 1) {
 875                 ERROR("Cannot modify \"%"TS"\": is part of a split WIM",
 876                       wim->filename);
 877                 return WIMLIB_ERR_WIM_IS_READONLY;
 878         }
 879         if (wim->hdr.flags & WIM_HDR_FLAG_READONLY) {
 880                 ERROR("Cannot modify \"%"TS"\": is marked read-only",
 881                       wim->filename);
 882                 return WIMLIB_ERR_WIM_IS_READONLY;
 883         }
 884         return 0;
 885 }
 886
 887 /* Release a reference to a WIMStruct.  If the reference count reaches 0, the
 888  * WIMStruct is freed.  */
 889 void
 890 wim_decrement_refcnt(WIMStruct *wim)
 891 {
 892         wimlib_assert(wim->refcnt > 0);
 893         if (--wim->refcnt != 0)
 894                 return;
 895         if (filedes_valid(&wim->in_fd))
 896                 filedes_close(&wim->in_fd);
 897         if (filedes_valid(&wim->out_fd))
 898                 filedes_close(&wim->out_fd);
 899         wimlib_free_decompressor(wim->decompressor);
 900         xml_free_info_struct(wim->xml_info);
 901         FREE(wim->filename);
 902         FREE(wim);
 903 }
 904
 905 /* API function documented in wimlib.h  */
 906 WIMLIBAPI void
 907 wimlib_free(WIMStruct *wim)
 908 {
 909         if (!wim)
 910                 return;
 911
 912         /* The blob table and image metadata are freed immediately, but other
 913          * members of the WIMStruct such as the input file descriptor are
 914          * retained until no more exported resources reference the WIMStruct. */
 915
 916         free_blob_table(wim->blob_table);
 917         wim->blob_table = NULL;
 918         if (wim->image_metadata != NULL) {
 919                 deselect_current_wim_image(wim);
 920                 for (int i = 0; i < wim->hdr.image_count; i++)
 921                         put_image_metadata(wim->image_metadata[i]);
 922                 FREE(wim->image_metadata);
 923                 wim->image_metadata = NULL;
 924         }
 925
 926         wim_decrement_refcnt(wim);
 927 }
 928
 929 /* API function documented in wimlib.h  */
 930 WIMLIBAPI u32
 931 wimlib_get_version(void)
 932 {
 933         return (WIMLIB_MAJOR_VERSION << 20) |
 934                (WIMLIB_MINOR_VERSION << 10) |
 935                 WIMLIB_PATCH_VERSION;
 936 }
 937
 938 WIMLIBAPI const tchar *
 939 wimlib_get_version_string(void)
 940 {
 941         return T(PACKAGE_VERSION);
 942 }
 943
 944 static bool lib_initialized = false;
 945 static pthread_mutex_t lib_initialization_mutex = PTHREAD_MUTEX_INITIALIZER;
 946
 947 /* API function documented in wimlib.h  */
 948 WIMLIBAPI int
 949 wimlib_global_init(int init_flags)
 950 {
 951         int ret = 0;
 952
 953         if (lib_initialized)
 954                 goto out;
 955
 956         pthread_mutex_lock(&lib_initialization_mutex);
 957
 958         if (lib_initialized)
 959                 goto out_unlock;
 960
 961 #ifdef ENABLE_ERROR_MESSAGES
 962         if (!wimlib_error_file)
 963                 wimlib_error_file = stderr;
 964 #endif
 965
 966         ret = WIMLIB_ERR_INVALID_PARAM;
 967         if (init_flags & ~(WIMLIB_INIT_FLAG_ASSUME_UTF8 |
 968                            WIMLIB_INIT_FLAG_DONT_ACQUIRE_PRIVILEGES |
 969                            WIMLIB_INIT_FLAG_STRICT_CAPTURE_PRIVILEGES |
 970                            WIMLIB_INIT_FLAG_STRICT_APPLY_PRIVILEGES |
 971                            WIMLIB_INIT_FLAG_DEFAULT_CASE_SENSITIVE |
 972                            WIMLIB_INIT_FLAG_DEFAULT_CASE_INSENSITIVE))
 973                 goto out_unlock;
 974
 975         ret = WIMLIB_ERR_INVALID_PARAM;
 976         if ((init_flags & (WIMLIB_INIT_FLAG_DEFAULT_CASE_SENSITIVE |
 977                            WIMLIB_INIT_FLAG_DEFAULT_CASE_INSENSITIVE))
 978                         == (WIMLIB_INIT_FLAG_DEFAULT_CASE_SENSITIVE |
 979                             WIMLIB_INIT_FLAG_DEFAULT_CASE_INSENSITIVE))
 980                 goto out_unlock;
 981
 982         xml_global_init();
 983 #ifdef __WIN32__
 984         ret = win32_global_init(init_flags);
 985         if (ret)
 986                 goto out_unlock;
 987 #endif
 988         init_upcase();
 989         if (init_flags & WIMLIB_INIT_FLAG_DEFAULT_CASE_SENSITIVE)
 990                 default_ignore_case = false;
 991         else if (init_flags & WIMLIB_INIT_FLAG_DEFAULT_CASE_INSENSITIVE)
 992                 default_ignore_case = true;
 993         lib_initialized = true;
 994         ret = 0;
 995 out_unlock:
 996         pthread_mutex_unlock(&lib_initialization_mutex);
 997 out:
 998         return ret;
 999 }
1000
1001 /* API function documented in wimlib.h  */
1002 WIMLIBAPI void
1003 wimlib_global_cleanup(void)
1004 {
1005         if (!lib_initialized)
1006                 return;
1007
1008         pthread_mutex_lock(&lib_initialization_mutex);
1009
1010         if (!lib_initialized)
1011                 goto out_unlock;
1012
1013         xml_global_cleanup();
1014 #ifdef __WIN32__
1015         win32_global_cleanup();
1016 #endif
1017
1018         wimlib_set_error_file(NULL);
1019         lib_initialized = false;
1020
1021 out_unlock:
1022         pthread_mutex_unlock(&lib_initialization_mutex);
1023 }