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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, 2015 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 <pthread.h>
  32 #include <stdlib.h>
  33 #include <unistd.h>
  34
  35 #include "wimlib.h"
  36 #include "wimlib/assert.h"
  37 #include "wimlib/blob_table.h"
  38 #include "wimlib/dentry.h"
  39 #include "wimlib/encoding.h"
  40 #include "wimlib/file_io.h"
  41 #include "wimlib/integrity.h"
  42 #include "wimlib/metadata.h"
  43 #include "wimlib/ntfs_3g.h" /* for libntfs3g_global_init() */
  44 #include "wimlib/security.h"
  45 #include "wimlib/wim.h"
  46 #include "wimlib/xml.h"
  47 #include "wimlib/win32.h"
  48
  49 /* Information about the available compression types for the WIM format.  */
  50 static const struct {
  51         const tchar *name;
  52         u32 min_chunk_size;
  53         u32 max_chunk_size;
  54         u32 default_nonsolid_chunk_size;
  55         u32 default_solid_chunk_size;
  56 } wim_ctype_info[] = {
  57         [WIMLIB_COMPRESSION_TYPE_NONE] = {
  58                 .name = T("None"),
  59                 .min_chunk_size = 0,
  60                 .max_chunk_size = 0,
  61                 .default_nonsolid_chunk_size = 0,
  62                 .default_solid_chunk_size = 0,
  63         },
  64         [WIMLIB_COMPRESSION_TYPE_XPRESS] = {
  65                 .name = T("XPRESS"),
  66                 .min_chunk_size = 4096,
  67                 .max_chunk_size = 65536,
  68                 .default_nonsolid_chunk_size = 32768,
  69                 .default_solid_chunk_size = 32768,
  70         },
  71         [WIMLIB_COMPRESSION_TYPE_LZX] = {
  72                 .name = T("LZX"),
  73                 .min_chunk_size = 32768,
  74                 .max_chunk_size = 2097152,
  75                 .default_nonsolid_chunk_size = 32768,
  76                 .default_solid_chunk_size = 32768,
  77         },
  78         [WIMLIB_COMPRESSION_TYPE_LZMS] = {
  79                 .name = T("LZMS"),
  80                 .min_chunk_size = 32768,
  81                 .max_chunk_size = 1073741824,
  82                 .default_nonsolid_chunk_size = 131072,
  83                 .default_solid_chunk_size = 67108864,
  84         },
  85 };
  86
  87 /* Is the specified compression type valid?  */
  88 static bool
  89 wim_compression_type_valid(enum wimlib_compression_type ctype)
  90 {
  91         return (unsigned)ctype < ARRAY_LEN(wim_ctype_info) &&
  92                wim_ctype_info[(unsigned)ctype].name != NULL;
  93 }
  94
  95 /* Is the specified chunk size valid for the compression type?  */
  96 static bool
  97 wim_chunk_size_valid(u32 chunk_size, enum wimlib_compression_type ctype)
  98 {
  99         if (!(chunk_size == 0 || is_power_of_2(chunk_size)))
 100                 return false;
 101
 102         return chunk_size >= wim_ctype_info[(unsigned)ctype].min_chunk_size &&
 103                chunk_size <= wim_ctype_info[(unsigned)ctype].max_chunk_size;
 104 }
 105
 106 /* Return the default chunk size to use for the specified compression type in
 107  * non-solid resources.  */
 108 static u32
 109 wim_default_nonsolid_chunk_size(enum wimlib_compression_type ctype)
 110 {
 111         return wim_ctype_info[(unsigned)ctype].default_nonsolid_chunk_size;
 112 }
 113
 114 /* Return the default chunk size to use for the specified compression type in
 115  * solid resources.  */
 116 static u32
 117 wim_default_solid_chunk_size(enum wimlib_compression_type ctype)
 118 {
 119         return wim_ctype_info[(unsigned)ctype].default_solid_chunk_size;
 120 }
 121
 122 /* Return the default compression type to use in solid resources.  */
 123 static enum wimlib_compression_type
 124 wim_default_solid_compression_type(void)
 125 {
 126         return WIMLIB_COMPRESSION_TYPE_LZMS;
 127 }
 128
 129 static int
 130 is_blob_in_solid_resource(struct blob_descriptor *blob, void *_ignore)
 131 {
 132         return blob->blob_location == BLOB_IN_WIM &&
 133                 (blob->rdesc->flags & WIM_RESHDR_FLAG_SOLID);
 134 }
 135
 136 bool
 137 wim_has_solid_resources(const WIMStruct *wim)
 138 {
 139         return for_blob_in_table(wim->blob_table, is_blob_in_solid_resource, NULL);
 140 }
 141
 142 static WIMStruct *
 143 new_wim_struct(void)
 144 {
 145         WIMStruct *wim = CALLOC(1, sizeof(WIMStruct));
 146         if (!wim)
 147                 return NULL;
 148
 149         filedes_invalidate(&wim->in_fd);
 150         filedes_invalidate(&wim->out_fd);
 151         wim->out_solid_compression_type = wim_default_solid_compression_type();
 152         wim->out_solid_chunk_size = wim_default_solid_chunk_size(
 153                                         wim->out_solid_compression_type);
 154         INIT_LIST_HEAD(&wim->subwims);
 155         return wim;
 156 }
 157
 158 /* API function documented in wimlib.h  */
 159 WIMLIBAPI int
 160 wimlib_create_new_wim(enum wimlib_compression_type ctype, WIMStruct **wim_ret)
 161 {
 162         int ret;
 163         WIMStruct *wim;
 164
 165         ret = wimlib_global_init(WIMLIB_INIT_FLAG_ASSUME_UTF8);
 166         if (ret)
 167                 return ret;
 168
 169         if (!wim_ret)
 170                 return WIMLIB_ERR_INVALID_PARAM;
 171
 172         if (!wim_compression_type_valid(ctype))
 173                 return WIMLIB_ERR_INVALID_COMPRESSION_TYPE;
 174
 175         wim = new_wim_struct();
 176         if (!wim)
 177                 return WIMLIB_ERR_NOMEM;
 178
 179         wim->xml_info = xml_new_info_struct();
 180         wim->blob_table = new_blob_table(9001);
 181         if (!wim->xml_info || !wim->blob_table) {
 182                 wimlib_free(wim);
 183                 return WIMLIB_ERR_NOMEM;
 184         }
 185
 186         /* Fill in wim->hdr with default values  */
 187         wim->hdr.magic = WIM_MAGIC;
 188         wim->hdr.wim_version = WIM_VERSION_DEFAULT;
 189         wim->hdr.flags = 0;
 190         wim->hdr.chunk_size = 0;
 191         generate_guid(wim->hdr.guid);
 192         wim->hdr.part_number = 1;
 193         wim->hdr.total_parts = 1;
 194         wim->hdr.image_count = 0;
 195         wim->hdr.boot_idx = 0;
 196
 197         wim->compression_type = WIMLIB_COMPRESSION_TYPE_NONE;
 198         wim->chunk_size = wim->hdr.chunk_size;
 199
 200         /* Set the output compression type  */
 201         wim->out_compression_type = ctype;
 202         wim->out_chunk_size = wim_default_nonsolid_chunk_size(ctype);
 203
 204         *wim_ret = wim;
 205         return 0;
 206 }
 207
 208 static void
 209 destroy_image_metadata(struct wim_image_metadata *imd,
 210                        struct blob_table *table,
 211                        bool free_metadata_blob_descriptor)
 212 {
 213         free_dentry_tree(imd->root_dentry, table);
 214         imd->root_dentry = NULL;
 215         free_wim_security_data(imd->security_data);
 216         imd->security_data = NULL;
 217
 218         if (free_metadata_blob_descriptor) {
 219                 free_blob_descriptor(imd->metadata_blob);
 220                 imd->metadata_blob = NULL;
 221         }
 222         if (!table) {
 223                 struct blob_descriptor *blob, *tmp;
 224                 list_for_each_entry_safe(blob, tmp, &imd->unhashed_blobs, unhashed_list)
 225                         free_blob_descriptor(blob);
 226         }
 227         INIT_LIST_HEAD(&imd->unhashed_blobs);
 228         INIT_HLIST_HEAD(&imd->inode_list);
 229 }
 230
 231 void
 232 put_image_metadata(struct wim_image_metadata *imd, struct blob_table *table)
 233 {
 234         if (imd && --imd->refcnt == 0) {
 235                 destroy_image_metadata(imd, table, true);
 236                 FREE(imd);
 237         }
 238 }
 239
 240 /* Appends the specified image metadata structure to the array of image metadata
 241  * for a WIM, and increments the image count. */
 242 int
 243 append_image_metadata(WIMStruct *wim, struct wim_image_metadata *imd)
 244 {
 245         struct wim_image_metadata **imd_array;
 246
 247         imd_array = REALLOC(wim->image_metadata,
 248                             sizeof(wim->image_metadata[0]) * (wim->hdr.image_count + 1));
 249
 250         if (!imd_array)
 251                 return WIMLIB_ERR_NOMEM;
 252         wim->image_metadata = imd_array;
 253         imd_array[wim->hdr.image_count++] = imd;
 254         return 0;
 255 }
 256
 257 struct wim_image_metadata *
 258 new_image_metadata(void)
 259 {
 260         struct wim_image_metadata *imd;
 261
 262         imd = CALLOC(1, sizeof(*imd));
 263         if (imd) {
 264                 imd->refcnt = 1;
 265                 INIT_HLIST_HEAD(&imd->inode_list);
 266                 INIT_LIST_HEAD(&imd->unhashed_blobs);
 267         }
 268         return imd;
 269 }
 270
 271 static struct wim_image_metadata **
 272 new_image_metadata_array(unsigned num_images)
 273 {
 274         struct wim_image_metadata **imd_array;
 275
 276         imd_array = CALLOC(num_images, sizeof(imd_array[0]));
 277
 278         if (!imd_array)
 279                 return NULL;
 280         for (unsigned i = 0; i < num_images; i++) {
 281                 imd_array[i] = new_image_metadata();
 282                 if (unlikely(!imd_array[i])) {
 283                         for (unsigned j = 0; j < i; j++)
 284                                 put_image_metadata(imd_array[j], NULL);
 285                         FREE(imd_array);
 286                         return NULL;
 287                 }
 288         }
 289         return imd_array;
 290 }
 291
 292
 293 /*
 294  * Load the metadata for the specified WIM image into memory and set it
 295  * as the WIMStruct's currently selected image.
 296  *
 297  * @wim
 298  *      The WIMStruct for the WIM.
 299  * @image
 300  *      The 1-based index of the image in the WIM to select.
 301  *
 302  * On success, 0 will be returned, wim->current_image will be set to
 303  * @image, and wim_get_current_image_metadata() can be used to retrieve
 304  * metadata information for the image.
 305  *
 306  * On failure, WIMLIB_ERR_INVALID_IMAGE, WIMLIB_ERR_METADATA_NOT_FOUND,
 307  * or another error code will be returned.
 308  */
 309 int
 310 select_wim_image(WIMStruct *wim, int image)
 311 {
 312         struct wim_image_metadata *imd;
 313         int ret;
 314
 315         if (image == WIMLIB_NO_IMAGE)
 316                 return WIMLIB_ERR_INVALID_IMAGE;
 317
 318         if (image == wim->current_image)
 319                 return 0;
 320
 321         if (image < 1 || image > wim->hdr.image_count)
 322                 return WIMLIB_ERR_INVALID_IMAGE;
 323
 324         if (!wim_has_metadata(wim))
 325                 return WIMLIB_ERR_METADATA_NOT_FOUND;
 326
 327         /* If a valid image is currently selected, its metadata can be freed if
 328          * it is not dirty and no other WIMStructs may have it selected.  */
 329         deselect_current_wim_image(wim);
 330         wim->current_image = image;
 331         imd = wim_get_current_image_metadata(wim);
 332         if (imd->root_dentry || is_image_dirty(imd)) {
 333                 ret = 0;
 334         } else {
 335                 ret = read_metadata_resource(imd);
 336                 if (ret)
 337                         wim->current_image = WIMLIB_NO_IMAGE;
 338         }
 339         return ret;
 340 }
 341
 342 void
 343 deselect_current_wim_image(WIMStruct *wim)
 344 {
 345         struct wim_image_metadata *imd;
 346         if (wim->current_image == WIMLIB_NO_IMAGE)
 347                 return;
 348         imd = wim_get_current_image_metadata(wim);
 349         if (!is_image_dirty(imd) && imd->refcnt == 1) {
 350                 wimlib_assert(list_empty(&imd->unhashed_blobs));
 351                 destroy_image_metadata(imd, NULL, false);
 352         }
 353         wim->current_image = WIMLIB_NO_IMAGE;
 354 }
 355
 356 /*
 357  * Calls a function on images in the WIM.  If @image is WIMLIB_ALL_IMAGES,
 358  * @visitor is called on the WIM once for each image, with each image selected
 359  * as the current image in turn.  If @image is a certain image, @visitor is
 360  * called on the WIM only once, with that image selected.
 361  */
 362 int
 363 for_image(WIMStruct *wim, int image, int (*visitor)(WIMStruct *))
 364 {
 365         int ret;
 366         int start;
 367         int end;
 368         int i;
 369
 370         if (image == WIMLIB_ALL_IMAGES) {
 371                 start = 1;
 372                 end = wim->hdr.image_count;
 373         } else if (image >= 1 && image <= wim->hdr.image_count) {
 374                 start = image;
 375                 end = image;
 376         } else {
 377                 return WIMLIB_ERR_INVALID_IMAGE;
 378         }
 379         for (i = start; i <= end; i++) {
 380                 ret = select_wim_image(wim, i);
 381                 if (ret != 0)
 382                         return ret;
 383                 ret = visitor(wim);
 384                 if (ret != 0)
 385                         return ret;
 386         }
 387         return 0;
 388 }
 389
 390 /* API function documented in wimlib.h  */
 391 WIMLIBAPI int
 392 wimlib_resolve_image(WIMStruct *wim, const tchar *image_name_or_num)
 393 {
 394         tchar *p;
 395         long image;
 396         int i;
 397
 398         if (!image_name_or_num || !*image_name_or_num)
 399                 return WIMLIB_NO_IMAGE;
 400
 401         if (!tstrcasecmp(image_name_or_num, T("all"))
 402             || !tstrcasecmp(image_name_or_num, T("*")))
 403                 return WIMLIB_ALL_IMAGES;
 404         image = tstrtol(image_name_or_num, &p, 10);
 405         if (p != image_name_or_num && *p == T('\0') && image > 0) {
 406                 if (image > wim->hdr.image_count)
 407                         return WIMLIB_NO_IMAGE;
 408                 return image;
 409         } else {
 410                 for (i = 1; i <= wim->hdr.image_count; i++) {
 411                         if (!tstrcmp(image_name_or_num,
 412                                      wimlib_get_image_name(wim, i)))
 413                                 return i;
 414                 }
 415                 return WIMLIB_NO_IMAGE;
 416         }
 417 }
 418
 419 /* API function documented in wimlib.h  */
 420 WIMLIBAPI void
 421 wimlib_print_available_images(const WIMStruct *wim, int image)
 422 {
 423         int first;
 424         int last;
 425         int i;
 426         int n;
 427         if (image == WIMLIB_ALL_IMAGES) {
 428                 n = tprintf(T("Available Images:\n"));
 429                 first = 1;
 430                 last = wim->hdr.image_count;
 431         } else if (image >= 1 && image <= wim->hdr.image_count) {
 432                 n = tprintf(T("Information for Image %d\n"), image);
 433                 first = image;
 434                 last = image;
 435         } else {
 436                 tprintf(T("wimlib_print_available_images(): Invalid image %d"),
 437                         image);
 438                 return;
 439         }
 440         for (i = 0; i < n - 1; i++)
 441                 tputchar(T('-'));
 442         tputchar(T('\n'));
 443         for (i = first; i <= last; i++)
 444                 xml_print_image_info(wim->xml_info, i);
 445 }
 446
 447 /* API function documented in wimlib.h  */
 448 WIMLIBAPI int
 449 wimlib_get_wim_info(WIMStruct *wim, struct wimlib_wim_info *info)
 450 {
 451         memset(info, 0, sizeof(struct wimlib_wim_info));
 452         copy_guid(info->guid, wim->hdr.guid);
 453         info->image_count = wim->hdr.image_count;
 454         info->boot_index = wim->hdr.boot_idx;
 455         info->wim_version = wim->hdr.wim_version;
 456         info->chunk_size = wim->chunk_size;
 457         info->part_number = wim->hdr.part_number;
 458         info->total_parts = wim->hdr.total_parts;
 459         info->compression_type = wim->compression_type;
 460         info->total_bytes = xml_get_total_bytes(wim->xml_info);
 461         info->has_integrity_table = wim_has_integrity_table(wim);
 462         info->opened_from_file = (wim->filename != NULL);
 463         info->is_readonly = (wim->hdr.flags & WIM_HDR_FLAG_READONLY) ||
 464                              (wim->hdr.total_parts != 1) ||
 465                              (wim->filename && taccess(wim->filename, W_OK));
 466         info->has_rpfix = (wim->hdr.flags & WIM_HDR_FLAG_RP_FIX) != 0;
 467         info->is_marked_readonly = (wim->hdr.flags & WIM_HDR_FLAG_READONLY) != 0;
 468         info->write_in_progress = (wim->hdr.flags & WIM_HDR_FLAG_WRITE_IN_PROGRESS) != 0;
 469         info->metadata_only = (wim->hdr.flags & WIM_HDR_FLAG_METADATA_ONLY) != 0;
 470         info->resource_only = (wim->hdr.flags & WIM_HDR_FLAG_RESOURCE_ONLY) != 0;
 471         info->spanned = (wim->hdr.flags & WIM_HDR_FLAG_SPANNED) != 0;
 472         info->pipable = wim_is_pipable(wim);
 473         return 0;
 474 }
 475
 476 /* API function documented in wimlib.h  */
 477 WIMLIBAPI int
 478 wimlib_set_wim_info(WIMStruct *wim, const struct wimlib_wim_info *info, int which)
 479 {
 480         if (which & ~(WIMLIB_CHANGE_READONLY_FLAG |
 481                       WIMLIB_CHANGE_GUID |
 482                       WIMLIB_CHANGE_BOOT_INDEX |
 483                       WIMLIB_CHANGE_RPFIX_FLAG))
 484                 return WIMLIB_ERR_INVALID_PARAM;
 485
 486         if ((which & WIMLIB_CHANGE_BOOT_INDEX) &&
 487             info->boot_index > wim->hdr.image_count)
 488                 return WIMLIB_ERR_INVALID_IMAGE;
 489
 490         if (which & WIMLIB_CHANGE_READONLY_FLAG) {
 491                 if (info->is_marked_readonly)
 492                         wim->hdr.flags |= WIM_HDR_FLAG_READONLY;
 493                 else
 494                         wim->hdr.flags &= ~WIM_HDR_FLAG_READONLY;
 495         }
 496
 497         if (which & WIMLIB_CHANGE_GUID)
 498                 copy_guid(wim->hdr.guid, info->guid);
 499
 500         if (which & WIMLIB_CHANGE_BOOT_INDEX)
 501                 wim->hdr.boot_idx = info->boot_index;
 502
 503         if (which & WIMLIB_CHANGE_RPFIX_FLAG) {
 504                 if (info->has_rpfix)
 505                         wim->hdr.flags |= WIM_HDR_FLAG_RP_FIX;
 506                 else
 507                         wim->hdr.flags &= ~WIM_HDR_FLAG_RP_FIX;
 508         }
 509         return 0;
 510 }
 511
 512 /* API function documented in wimlib.h  */
 513 WIMLIBAPI int
 514 wimlib_set_output_compression_type(WIMStruct *wim,
 515                                    enum wimlib_compression_type ctype)
 516 {
 517         if (!wim_compression_type_valid(ctype))
 518                 return WIMLIB_ERR_INVALID_COMPRESSION_TYPE;
 519
 520         wim->out_compression_type = ctype;
 521
 522         /* Reset the chunk size if it's no longer valid.  */
 523         if (!wim_chunk_size_valid(wim->out_chunk_size, ctype))
 524                 wim->out_chunk_size = wim_default_nonsolid_chunk_size(ctype);
 525         return 0;
 526 }
 527
 528 /* API function documented in wimlib.h  */
 529 WIMLIBAPI int
 530 wimlib_set_output_pack_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         /* Solid resources can't be uncompressed.  */
 537         if (ctype == WIMLIB_COMPRESSION_TYPE_NONE)
 538                 return WIMLIB_ERR_INVALID_COMPRESSION_TYPE;
 539
 540         wim->out_solid_compression_type = ctype;
 541
 542         /* Reset the chunk size if it's no longer valid.  */
 543         if (!wim_chunk_size_valid(wim->out_solid_chunk_size, ctype))
 544                 wim->out_solid_chunk_size = wim_default_solid_chunk_size(ctype);
 545         return 0;
 546 }
 547
 548 /* API function documented in wimlib.h  */
 549 WIMLIBAPI int
 550 wimlib_set_output_chunk_size(WIMStruct *wim, u32 chunk_size)
 551 {
 552         if (chunk_size == 0) {
 553                 wim->out_chunk_size =
 554                         wim_default_nonsolid_chunk_size(wim->out_compression_type);
 555                 return 0;
 556         }
 557
 558         if (!wim_chunk_size_valid(chunk_size, wim->out_compression_type))
 559                 return WIMLIB_ERR_INVALID_CHUNK_SIZE;
 560
 561         wim->out_chunk_size = chunk_size;
 562         return 0;
 563 }
 564
 565 /* API function documented in wimlib.h  */
 566 WIMLIBAPI int
 567 wimlib_set_output_pack_chunk_size(WIMStruct *wim, u32 chunk_size)
 568 {
 569         if (chunk_size == 0) {
 570                 wim->out_solid_chunk_size =
 571                         wim_default_solid_chunk_size(wim->out_solid_compression_type);
 572                 return 0;
 573         }
 574
 575         if (!wim_chunk_size_valid(chunk_size, wim->out_solid_compression_type))
 576                 return WIMLIB_ERR_INVALID_CHUNK_SIZE;
 577
 578         wim->out_solid_chunk_size = chunk_size;
 579         return 0;
 580 }
 581
 582 /* API function documented in wimlib.h  */
 583 WIMLIBAPI const tchar *
 584 wimlib_get_compression_type_string(enum wimlib_compression_type ctype)
 585 {
 586         if (!wim_compression_type_valid(ctype))
 587                 return T("Invalid");
 588
 589         return wim_ctype_info[(unsigned)ctype].name;
 590 }
 591
 592 WIMLIBAPI void
 593 wimlib_register_progress_function(WIMStruct *wim,
 594                                   wimlib_progress_func_t progfunc,
 595                                   void *progctx)
 596 {
 597         wim->progfunc = progfunc;
 598         wim->progctx = progctx;
 599 }
 600
 601 static int
 602 open_wim_file(const tchar *filename, struct filedes *fd_ret)
 603 {
 604         int raw_fd;
 605
 606         raw_fd = topen(filename, O_RDONLY | O_BINARY);
 607         if (raw_fd < 0) {
 608                 ERROR_WITH_ERRNO("Can't open \"%"TS"\" read-only", filename);
 609                 return WIMLIB_ERR_OPEN;
 610         }
 611         filedes_init(fd_ret, raw_fd);
 612         return 0;
 613 }
 614
 615 /*
 616  * Begins the reading of a WIM file; opens the file and reads its header and
 617  * blob table, and optionally checks the integrity.
 618  */
 619 static int
 620 begin_read(WIMStruct *wim, const void *wim_filename_or_fd, int open_flags)
 621 {
 622         int ret;
 623         const tchar *wimfile;
 624
 625         if (open_flags & WIMLIB_OPEN_FLAG_FROM_PIPE) {
 626                 wimfile = NULL;
 627                 filedes_init(&wim->in_fd, *(const int*)wim_filename_or_fd);
 628                 wim->in_fd.is_pipe = 1;
 629         } else {
 630                 wimfile = wim_filename_or_fd;
 631                 ret = open_wim_file(wimfile, &wim->in_fd);
 632                 if (ret)
 633                         return ret;
 634
 635                 /* The absolute path to the WIM is requested so that
 636                  * wimlib_overwrite() still works even if the process changes
 637                  * its working directory.  This actually happens if a WIM is
 638                  * mounted read-write, since the FUSE thread changes directory
 639                  * to "/", and it needs to be able to find the WIM file again.
 640                  *
 641                  * This will break if the full path to the WIM changes in the
 642                  * intervening time...
 643                  *
 644                  * Warning: in Windows native builds, realpath() calls the
 645                  * replacement function in win32_replacements.c.
 646                  */
 647                 wim->filename = realpath(wimfile, NULL);
 648                 if (!wim->filename) {
 649                         ERROR_WITH_ERRNO("Failed to get full path to file "
 650                                          "\"%"TS"\"", wimfile);
 651                         if (errno == ENOMEM)
 652                                 return WIMLIB_ERR_NOMEM;
 653                         else
 654                                 return WIMLIB_ERR_NO_FILENAME;
 655                 }
 656         }
 657
 658         ret = read_wim_header(wim, &wim->hdr);
 659         if (ret)
 660                 return ret;
 661
 662         if (wim->hdr.flags & WIM_HDR_FLAG_WRITE_IN_PROGRESS) {
 663                 WARNING("The WIM_HDR_FLAG_WRITE_IN_PROGRESS flag is set in the header of\n"
 664                         "          \"%"TS"\".  It may be being changed by another process,\n"
 665                         "          or a process may have crashed while writing the WIM.",
 666                         wimfile);
 667         }
 668
 669         if (open_flags & WIMLIB_OPEN_FLAG_WRITE_ACCESS) {
 670                 ret = can_modify_wim(wim);
 671                 if (ret)
 672                         return ret;
 673         }
 674
 675         if ((open_flags & WIMLIB_OPEN_FLAG_ERROR_IF_SPLIT) &&
 676             (wim->hdr.total_parts != 1))
 677                 return WIMLIB_ERR_IS_SPLIT_WIM;
 678
 679         /* If the boot index is invalid, print a warning and set it to 0 */
 680         if (wim->hdr.boot_idx > wim->hdr.image_count) {
 681                 WARNING("Ignoring invalid boot index.");
 682                 wim->hdr.boot_idx = 0;
 683         }
 684
 685         /* Check and cache the compression type */
 686         if (wim->hdr.flags & WIM_HDR_FLAG_COMPRESSION) {
 687                 if (wim->hdr.flags & WIM_HDR_FLAG_COMPRESS_LZX) {
 688                         wim->compression_type = WIMLIB_COMPRESSION_TYPE_LZX;
 689                 } else if (wim->hdr.flags & (WIM_HDR_FLAG_COMPRESS_XPRESS |
 690                                              WIM_HDR_FLAG_COMPRESS_XPRESS_2)) {
 691                         wim->compression_type = WIMLIB_COMPRESSION_TYPE_XPRESS;
 692                 } else if (wim->hdr.flags & WIM_HDR_FLAG_COMPRESS_LZMS) {
 693                         wim->compression_type = WIMLIB_COMPRESSION_TYPE_LZMS;
 694                 } else {
 695                         return WIMLIB_ERR_INVALID_COMPRESSION_TYPE;
 696                 }
 697         } else {
 698                 wim->compression_type = WIMLIB_COMPRESSION_TYPE_NONE;
 699         }
 700         wim->out_compression_type = wim->compression_type;
 701
 702         /* Check and cache the chunk size.  */
 703         wim->chunk_size = wim->hdr.chunk_size;
 704         wim->out_chunk_size = wim->chunk_size;
 705         if (!wim_chunk_size_valid(wim->chunk_size, wim->compression_type)) {
 706                 ERROR("Invalid chunk size (%"PRIu32" bytes) "
 707                       "for compression type %"TS"!", wim->chunk_size,
 708                       wimlib_get_compression_type_string(wim->compression_type));
 709                 return WIMLIB_ERR_INVALID_CHUNK_SIZE;
 710         }
 711
 712         if (open_flags & WIMLIB_OPEN_FLAG_CHECK_INTEGRITY) {
 713                 ret = check_wim_integrity(wim);
 714                 if (ret == WIM_INTEGRITY_NONEXISTENT) {
 715                         WARNING("\"%"TS"\" does not contain integrity "
 716                                 "information.  Skipping integrity check.",
 717                                 wimfile);
 718                 } else if (ret == WIM_INTEGRITY_NOT_OK) {
 719                         return WIMLIB_ERR_INTEGRITY;
 720                 } else if (ret != WIM_INTEGRITY_OK) {
 721                         return ret;
 722                 }
 723         }
 724
 725         if (wim->hdr.image_count != 0 && wim->hdr.part_number == 1) {
 726                 wim->image_metadata = new_image_metadata_array(wim->hdr.image_count);
 727                 if (!wim->image_metadata)
 728                         return WIMLIB_ERR_NOMEM;
 729         }
 730
 731         if (open_flags & WIMLIB_OPEN_FLAG_FROM_PIPE) {
 732                 wim->blob_table = new_blob_table(9001);
 733                 if (!wim->blob_table)
 734                         return WIMLIB_ERR_NOMEM;
 735         } else {
 736                 if (wim->hdr.blob_table_reshdr.uncompressed_size == 0 &&
 737                     wim->hdr.xml_data_reshdr.uncompressed_size == 0)
 738                         return WIMLIB_ERR_WIM_IS_INCOMPLETE;
 739
 740                 ret = read_wim_xml_data(wim);
 741                 if (ret)
 742                         return ret;
 743
 744                 if (xml_get_image_count(wim->xml_info) != wim->hdr.image_count) {
 745                         ERROR("The WIM's header is inconsistent with its XML data.\n"
 746                               "        Please submit a bug report if you believe this "
 747                               "WIM file should be considered valid.");
 748                         return WIMLIB_ERR_IMAGE_COUNT;
 749                 }
 750
 751                 ret = read_blob_table(wim);
 752                 if (ret)
 753                         return ret;
 754         }
 755         return 0;
 756 }
 757
 758 int
 759 open_wim_as_WIMStruct(const void *wim_filename_or_fd, int open_flags,
 760                       WIMStruct **wim_ret,
 761                       wimlib_progress_func_t progfunc, void *progctx)
 762 {
 763         WIMStruct *wim;
 764         int ret;
 765
 766         ret = wimlib_global_init(WIMLIB_INIT_FLAG_ASSUME_UTF8);
 767         if (ret)
 768                 return ret;
 769
 770         wim = new_wim_struct();
 771         if (!wim)
 772                 return WIMLIB_ERR_NOMEM;
 773
 774         wim->progfunc = progfunc;
 775         wim->progctx = progctx;
 776
 777         ret = begin_read(wim, wim_filename_or_fd, open_flags);
 778         if (ret) {
 779                 wimlib_free(wim);
 780                 return ret;
 781         }
 782
 783         *wim_ret = wim;
 784         return 0;
 785 }
 786
 787 /* API function documented in wimlib.h  */
 788 WIMLIBAPI int
 789 wimlib_open_wim_with_progress(const tchar *wimfile, int open_flags,
 790                               WIMStruct **wim_ret,
 791                               wimlib_progress_func_t progfunc, void *progctx)
 792 {
 793         if (open_flags & ~(WIMLIB_OPEN_FLAG_CHECK_INTEGRITY |
 794                            WIMLIB_OPEN_FLAG_ERROR_IF_SPLIT |
 795                            WIMLIB_OPEN_FLAG_WRITE_ACCESS))
 796                 return WIMLIB_ERR_INVALID_PARAM;
 797
 798         if (!wimfile || !*wimfile || !wim_ret)
 799                 return WIMLIB_ERR_INVALID_PARAM;
 800
 801         return open_wim_as_WIMStruct(wimfile, open_flags, wim_ret,
 802                                      progfunc, progctx);
 803 }
 804
 805 /* API function documented in wimlib.h  */
 806 WIMLIBAPI int
 807 wimlib_open_wim(const tchar *wimfile, int open_flags, WIMStruct **wim_ret)
 808 {
 809         return wimlib_open_wim_with_progress(wimfile, open_flags, wim_ret,
 810                                              NULL, NULL);
 811 }
 812
 813 /* Checksum all blobs that are unhashed (other than the metadata blobs), merging
 814  * them into the blob table as needed.  This is a no-op unless files have been
 815  * added to an image in the same WIMStruct.  */
 816 int
 817 wim_checksum_unhashed_blobs(WIMStruct *wim)
 818 {
 819         int ret;
 820
 821         if (!wim_has_metadata(wim))
 822                 return 0;
 823         for (int i = 0; i < wim->hdr.image_count; i++) {
 824                 struct blob_descriptor *blob, *tmp;
 825                 struct wim_image_metadata *imd = wim->image_metadata[i];
 826                 image_for_each_unhashed_blob_safe(blob, tmp, imd) {
 827                         struct blob_descriptor *new_blob;
 828                         ret = hash_unhashed_blob(blob, wim->blob_table, &new_blob);
 829                         if (ret)
 830                                 return ret;
 831                         if (new_blob != blob)
 832                                 free_blob_descriptor(blob);
 833                 }
 834         }
 835         return 0;
 836 }
 837
 838 /*
 839  * can_modify_wim - Check if a given WIM is writeable.  This is only the case if
 840  * it meets the following three conditions:
 841  *
 842  * 1. Write access is allowed to the underlying file (if any) at the filesystem level.
 843  * 2. The WIM is not part of a spanned set.
 844  * 3. The WIM_HDR_FLAG_READONLY flag is not set in the WIM header.
 845  *
 846  * Return value is 0 if writable; WIMLIB_ERR_WIM_IS_READONLY otherwise.
 847  */
 848 int
 849 can_modify_wim(WIMStruct *wim)
 850 {
 851         if (wim->filename) {
 852                 if (taccess(wim->filename, W_OK)) {
 853                         ERROR_WITH_ERRNO("Can't modify \"%"TS"\"", wim->filename);
 854                         return WIMLIB_ERR_WIM_IS_READONLY;
 855                 }
 856         }
 857         if (wim->hdr.total_parts != 1) {
 858                 ERROR("Cannot modify \"%"TS"\": is part of a split WIM",
 859                       wim->filename);
 860                 return WIMLIB_ERR_WIM_IS_READONLY;
 861         }
 862         if (wim->hdr.flags & WIM_HDR_FLAG_READONLY) {
 863                 ERROR("Cannot modify \"%"TS"\": is marked read-only",
 864                       wim->filename);
 865                 return WIMLIB_ERR_WIM_IS_READONLY;
 866         }
 867         return 0;
 868 }
 869
 870 /* API function documented in wimlib.h  */
 871 WIMLIBAPI void
 872 wimlib_free(WIMStruct *wim)
 873 {
 874         if (!wim)
 875                 return;
 876
 877         while (!list_empty(&wim->subwims)) {
 878                 WIMStruct *subwim;
 879
 880                 subwim = list_entry(wim->subwims.next, WIMStruct, subwim_node);
 881                 list_del(&subwim->subwim_node);
 882                 wimlib_free(subwim);
 883         }
 884
 885         if (filedes_valid(&wim->in_fd))
 886                 filedes_close(&wim->in_fd);
 887         if (filedes_valid(&wim->out_fd))
 888                 filedes_close(&wim->out_fd);
 889
 890         free_blob_table(wim->blob_table);
 891
 892         wimlib_free_decompressor(wim->decompressor);
 893
 894         FREE(wim->filename);
 895         xml_free_info_struct(wim->xml_info);
 896         if (wim->image_metadata) {
 897                 for (unsigned i = 0; i < wim->hdr.image_count; i++)
 898                         put_image_metadata(wim->image_metadata[i], NULL);
 899                 FREE(wim->image_metadata);
 900         }
 901         FREE(wim);
 902 }
 903
 904 static bool
 905 test_locale_ctype_utf8(void)
 906 {
 907 #ifdef __WIN32__
 908         return false;
 909 #else
 910         char *ctype = nl_langinfo(CODESET);
 911
 912         return (!strstr(ctype, "UTF-8") ||
 913                 !strstr(ctype, "UTF8") ||
 914                 !strstr(ctype, "utf8") ||
 915                 !strstr(ctype, "utf-8"));
 916 #endif
 917 }
 918
 919 /* API function documented in wimlib.h  */
 920 WIMLIBAPI u32
 921 wimlib_get_version(void)
 922 {
 923         return (WIMLIB_MAJOR_VERSION << 20) |
 924                (WIMLIB_MINOR_VERSION << 10) |
 925                 WIMLIB_PATCH_VERSION;
 926 }
 927
 928 static bool lib_initialized = false;
 929 static pthread_mutex_t lib_initialization_mutex = PTHREAD_MUTEX_INITIALIZER;
 930
 931 /* API function documented in wimlib.h  */
 932 WIMLIBAPI int
 933 wimlib_global_init(int init_flags)
 934 {
 935         int ret = 0;
 936
 937         if (lib_initialized)
 938                 goto out;
 939
 940         pthread_mutex_lock(&lib_initialization_mutex);
 941
 942         if (lib_initialized)
 943                 goto out_unlock;
 944
 945 #ifdef ENABLE_ERROR_MESSAGES
 946         if (!wimlib_error_file)
 947                 wimlib_error_file = stderr;
 948 #endif
 949
 950         ret = WIMLIB_ERR_INVALID_PARAM;
 951         if (init_flags & ~(WIMLIB_INIT_FLAG_ASSUME_UTF8 |
 952                            WIMLIB_INIT_FLAG_DONT_ACQUIRE_PRIVILEGES |
 953                            WIMLIB_INIT_FLAG_STRICT_CAPTURE_PRIVILEGES |
 954                            WIMLIB_INIT_FLAG_STRICT_APPLY_PRIVILEGES |
 955                            WIMLIB_INIT_FLAG_DEFAULT_CASE_SENSITIVE |
 956                            WIMLIB_INIT_FLAG_DEFAULT_CASE_INSENSITIVE))
 957                 goto out_unlock;
 958
 959         ret = WIMLIB_ERR_INVALID_PARAM;
 960         if ((init_flags & (WIMLIB_INIT_FLAG_DEFAULT_CASE_SENSITIVE |
 961                            WIMLIB_INIT_FLAG_DEFAULT_CASE_INSENSITIVE))
 962                         == (WIMLIB_INIT_FLAG_DEFAULT_CASE_SENSITIVE |
 963                             WIMLIB_INIT_FLAG_DEFAULT_CASE_INSENSITIVE))
 964                 goto out_unlock;
 965
 966         xml_global_init();
 967         if (!(init_flags & WIMLIB_INIT_FLAG_ASSUME_UTF8)) {
 968                 wimlib_mbs_is_utf8 = test_locale_ctype_utf8();
 969         #ifdef WITH_NTFS_3G
 970                 if (!wimlib_mbs_is_utf8)
 971                         libntfs3g_global_init();
 972         #endif
 973         }
 974 #ifdef __WIN32__
 975         ret = win32_global_init(init_flags);
 976         if (ret)
 977                 goto out_unlock;
 978 #endif
 979         iconv_global_init();
 980         init_upcase();
 981         if (init_flags & WIMLIB_INIT_FLAG_DEFAULT_CASE_SENSITIVE)
 982                 default_ignore_case = false;
 983         else if (init_flags & WIMLIB_INIT_FLAG_DEFAULT_CASE_INSENSITIVE)
 984                 default_ignore_case = true;
 985         lib_initialized = true;
 986         ret = 0;
 987 out_unlock:
 988         pthread_mutex_unlock(&lib_initialization_mutex);
 989 out:
 990         return ret;
 991 }
 992
 993 /* API function documented in wimlib.h  */
 994 WIMLIBAPI void
 995 wimlib_global_cleanup(void)
 996 {
 997         if (!lib_initialized)
 998                 return;
 999
1000         pthread_mutex_lock(&lib_initialization_mutex);
1001
1002         if (!lib_initialized)
1003                 goto out_unlock;
1004
1005         xml_global_cleanup();
1006         iconv_global_cleanup();
1007 #ifdef __WIN32__
1008         win32_global_cleanup();
1009 #endif
1010
1011         wimlib_set_error_file(NULL);
1012         lib_initialized = false;
1013
1014 out_unlock:
1015         pthread_mutex_unlock(&lib_initialization_mutex);
1016 }