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

   1 /*
   2  * extract.c
   3  *
   4  * Support for extracting WIM images, or files or directories contained in a WIM
   5  * image.
   6  */
   7
   8 /*
   9  * Copyright (C) 2012-2016 Eric Biggers
  10  *
  11  * This file is free software; you can redistribute it and/or modify it under
  12  * the terms of the GNU Lesser General Public License as published by the Free
  13  * Software Foundation; either version 3 of the License, or (at your option) any
  14  * later version.
  15  *
  16  * This file is distributed in the hope that it will be useful, but WITHOUT
  17  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  18  * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
  19  * details.
  20  *
  21  * You should have received a copy of the GNU Lesser General Public License
  22  * along with this file; if not, see http://www.gnu.org/licenses/.
  23  */
  24
  25 /*
  26  * This file provides the API functions wimlib_extract_image(),
  27  * wimlib_extract_image_from_pipe(), wimlib_extract_paths(), and
  28  * wimlib_extract_pathlist().  Internally, all end up calling
  29  * do_wimlib_extract_paths() and extract_trees().
  30  *
  31  * Although wimlib supports multiple extraction modes/backends (NTFS-3G, UNIX,
  32  * Win32), this file does not itself have code to extract files or directories
  33  * to any specific target; instead, it handles generic functionality and relies
  34  * on lower-level callback functions declared in `struct apply_operations' to do
  35  * the actual extraction.
  36  */
  37
  38 #ifdef HAVE_CONFIG_H
  39 #  include "config.h"
  40 #endif
  41
  42 #include <errno.h>
  43 #include <fcntl.h>
  44 #include <stdlib.h>
  45 #include <sys/stat.h>
  46 #include <unistd.h>
  47
  48 #include "wimlib/apply.h"
  49 #include "wimlib/assert.h"
  50 #include "wimlib/blob_table.h"
  51 #include "wimlib/dentry.h"
  52 #include "wimlib/encoding.h"
  53 #include "wimlib/endianness.h"
  54 #include "wimlib/error.h"
  55 #include "wimlib/metadata.h"
  56 #include "wimlib/object_id.h"
  57 #include "wimlib/pathlist.h"
  58 #include "wimlib/paths.h"
  59 #include "wimlib/pattern.h"
  60 #include "wimlib/reparse.h"
  61 #include "wimlib/resource.h"
  62 #include "wimlib/security.h"
  63 #include "wimlib/unix_data.h"
  64 #include "wimlib/wim.h"
  65 #include "wimlib/win32.h" /* for realpath() equivalent */
  66 #include "wimlib/xml.h"
  67
  68 #define WIMLIB_EXTRACT_FLAG_FROM_PIPE   0x80000000
  69 #define WIMLIB_EXTRACT_FLAG_IMAGEMODE   0x40000000
  70
  71 /* Keep in sync with wimlib.h  */
  72 #define WIMLIB_EXTRACT_MASK_PUBLIC                              \
  73         (WIMLIB_EXTRACT_FLAG_NTFS                       |       \
  74          WIMLIB_EXTRACT_FLAG_UNIX_DATA                  |       \
  75          WIMLIB_EXTRACT_FLAG_NO_ACLS                    |       \
  76          WIMLIB_EXTRACT_FLAG_STRICT_ACLS                |       \
  77          WIMLIB_EXTRACT_FLAG_RPFIX                      |       \
  78          WIMLIB_EXTRACT_FLAG_NORPFIX                    |       \
  79          WIMLIB_EXTRACT_FLAG_TO_STDOUT                  |       \
  80          WIMLIB_EXTRACT_FLAG_REPLACE_INVALID_FILENAMES  |       \
  81          WIMLIB_EXTRACT_FLAG_ALL_CASE_CONFLICTS         |       \
  82          WIMLIB_EXTRACT_FLAG_STRICT_TIMESTAMPS          |       \
  83          WIMLIB_EXTRACT_FLAG_STRICT_SHORT_NAMES         |       \
  84          WIMLIB_EXTRACT_FLAG_STRICT_SYMLINKS            |       \
  85          WIMLIB_EXTRACT_FLAG_GLOB_PATHS                 |       \
  86          WIMLIB_EXTRACT_FLAG_STRICT_GLOB                |       \
  87          WIMLIB_EXTRACT_FLAG_NO_ATTRIBUTES              |       \
  88          WIMLIB_EXTRACT_FLAG_NO_PRESERVE_DIR_STRUCTURE  |       \
  89          WIMLIB_EXTRACT_FLAG_WIMBOOT                    |       \
  90          WIMLIB_EXTRACT_FLAG_COMPACT_XPRESS4K           |       \
  91          WIMLIB_EXTRACT_FLAG_COMPACT_XPRESS8K           |       \
  92          WIMLIB_EXTRACT_FLAG_COMPACT_XPRESS16K          |       \
  93          WIMLIB_EXTRACT_FLAG_COMPACT_LZX                        \
  94          )
  95
  96 /* Send WIMLIB_PROGRESS_MSG_EXTRACT_FILE_STRUCTURE or
  97  * WIMLIB_PROGRESS_MSG_EXTRACT_METADATA.  */
  98 int
  99 do_file_extract_progress(struct apply_ctx *ctx, enum wimlib_progress_msg msg)
 100 {
 101         ctx->count_until_file_progress = 500;  /* Arbitrary value to limit calls  */
 102         return extract_progress(ctx, msg);
 103 }
 104
 105 static int
 106 start_file_phase(struct apply_ctx *ctx, u64 end_file_count, enum wimlib_progress_msg msg)
 107 {
 108         ctx->progress.extract.current_file_count = 0;
 109         ctx->progress.extract.end_file_count = end_file_count;
 110         return do_file_extract_progress(ctx, msg);
 111 }
 112
 113 int
 114 start_file_structure_phase(struct apply_ctx *ctx, u64 end_file_count)
 115 {
 116         return start_file_phase(ctx, end_file_count, WIMLIB_PROGRESS_MSG_EXTRACT_FILE_STRUCTURE);
 117 }
 118
 119 int
 120 start_file_metadata_phase(struct apply_ctx *ctx, u64 end_file_count)
 121 {
 122         return start_file_phase(ctx, end_file_count, WIMLIB_PROGRESS_MSG_EXTRACT_METADATA);
 123 }
 124
 125 static int
 126 end_file_phase(struct apply_ctx *ctx, enum wimlib_progress_msg msg)
 127 {
 128         ctx->progress.extract.current_file_count = ctx->progress.extract.end_file_count;
 129         return do_file_extract_progress(ctx, msg);
 130 }
 131
 132 int
 133 end_file_structure_phase(struct apply_ctx *ctx)
 134 {
 135         return end_file_phase(ctx, WIMLIB_PROGRESS_MSG_EXTRACT_FILE_STRUCTURE);
 136 }
 137
 138 int
 139 end_file_metadata_phase(struct apply_ctx *ctx)
 140 {
 141         return end_file_phase(ctx, WIMLIB_PROGRESS_MSG_EXTRACT_METADATA);
 142 }
 143
 144 #define PWM_FOUND_WIM_HDR (-1)
 145
 146 /* Read the header for a blob in a pipable WIM.  If @pwm_hdr_ret is not NULL,
 147  * also look for a pipable WIM header and return PWM_FOUND_WIM_HDR if found.  */
 148 static int
 149 read_pwm_blob_header(WIMStruct *pwm, u8 hash_ret[SHA1_HASH_SIZE],
 150                      struct wim_reshdr *reshdr_ret,
 151                      struct wim_header_disk *pwm_hdr_ret)
 152 {
 153         int ret;
 154         struct pwm_blob_hdr blob_hdr;
 155         u64 magic;
 156
 157         ret = full_read(&pwm->in_fd, &blob_hdr, sizeof(blob_hdr));
 158         if (unlikely(ret))
 159                 goto read_error;
 160
 161         magic = le64_to_cpu(blob_hdr.magic);
 162
 163         if (magic == PWM_MAGIC && pwm_hdr_ret != NULL) {
 164                 memcpy(pwm_hdr_ret, &blob_hdr, sizeof(blob_hdr));
 165                 ret = full_read(&pwm->in_fd,
 166                                 (u8 *)pwm_hdr_ret + sizeof(blob_hdr),
 167                                 sizeof(*pwm_hdr_ret) - sizeof(blob_hdr));
 168                 if (unlikely(ret))
 169                         goto read_error;
 170                 return PWM_FOUND_WIM_HDR;
 171         }
 172
 173         if (unlikely(magic != PWM_BLOB_MAGIC)) {
 174                 ERROR("Data read on pipe is invalid (expected blob header)");
 175                 return WIMLIB_ERR_INVALID_PIPABLE_WIM;
 176         }
 177
 178         copy_hash(hash_ret, blob_hdr.hash);
 179
 180         reshdr_ret->size_in_wim = 0; /* Not available  */
 181         reshdr_ret->flags = le32_to_cpu(blob_hdr.flags);
 182         reshdr_ret->offset_in_wim = pwm->in_fd.offset;
 183         reshdr_ret->uncompressed_size = le64_to_cpu(blob_hdr.uncompressed_size);
 184
 185         if (unlikely(reshdr_ret->uncompressed_size == 0)) {
 186                 ERROR("Data read on pipe is invalid (resource is of 0 size)");
 187                 return WIMLIB_ERR_INVALID_PIPABLE_WIM;
 188         }
 189
 190         return 0;
 191
 192 read_error:
 193         if (ret == WIMLIB_ERR_UNEXPECTED_END_OF_FILE)
 194                 ERROR("The pipe ended before all needed data was sent!");
 195         else
 196                 ERROR_WITH_ERRNO("Error reading pipable WIM from pipe");
 197         return ret;
 198 }
 199
 200 static int
 201 read_blobs_from_pipe(struct apply_ctx *ctx, const struct read_blob_callbacks *cbs)
 202 {
 203         int ret;
 204         u8 hash[SHA1_HASH_SIZE];
 205         struct wim_reshdr reshdr;
 206         struct wim_header_disk pwm_hdr;
 207         struct wim_resource_descriptor rdesc;
 208         struct blob_descriptor *blob;
 209
 210         copy_guid(ctx->progress.extract.guid, ctx->wim->hdr.guid);
 211         ctx->progress.extract.part_number = ctx->wim->hdr.part_number;
 212         ctx->progress.extract.total_parts = ctx->wim->hdr.total_parts;
 213         ret = extract_progress(ctx, WIMLIB_PROGRESS_MSG_EXTRACT_SPWM_PART_BEGIN);
 214         if (ret)
 215                 return ret;
 216
 217         while (ctx->num_blobs_remaining) {
 218
 219                 ret = read_pwm_blob_header(ctx->wim, hash, &reshdr, &pwm_hdr);
 220
 221                 if (ret == PWM_FOUND_WIM_HDR) {
 222                         u16 part_number = le16_to_cpu(pwm_hdr.part_number);
 223                         u16 total_parts = le16_to_cpu(pwm_hdr.total_parts);
 224
 225                         if (part_number == ctx->progress.extract.part_number &&
 226                             total_parts == ctx->progress.extract.total_parts &&
 227                             guids_equal(pwm_hdr.guid, ctx->progress.extract.guid))
 228                                 continue;
 229
 230                         copy_guid(ctx->progress.extract.guid, pwm_hdr.guid);
 231                         ctx->progress.extract.part_number = part_number;
 232                         ctx->progress.extract.total_parts = total_parts;
 233                         ret = extract_progress(ctx, WIMLIB_PROGRESS_MSG_EXTRACT_SPWM_PART_BEGIN);
 234                         if (ret)
 235                                 return ret;
 236
 237                         continue;
 238                 }
 239
 240                 if (ret)
 241                         return ret;
 242
 243                 if (!(reshdr.flags & WIM_RESHDR_FLAG_METADATA)
 244                     && (blob = lookup_blob(ctx->wim->blob_table, hash))
 245                     && (blob->out_refcnt))
 246                 {
 247                         wim_reshdr_to_desc_and_blob(&reshdr, ctx->wim, &rdesc, blob);
 248                         ret = read_blob_with_sha1(blob, cbs);
 249                         blob_unset_is_located_in_wim_resource(blob);
 250                         if (ret)
 251                                 return ret;
 252                         ctx->num_blobs_remaining--;
 253                 } else {
 254                         wim_reshdr_to_desc(&reshdr, ctx->wim, &rdesc);
 255                         ret = skip_wim_resource(&rdesc);
 256                         if (ret)
 257                                 return ret;
 258                 }
 259         }
 260
 261         return 0;
 262 }
 263
 264 static int
 265 handle_pwm_metadata_resource(WIMStruct *pwm, int image, bool is_needed)
 266 {
 267         struct blob_descriptor *blob;
 268         struct wim_reshdr reshdr;
 269         struct wim_resource_descriptor *rdesc;
 270         int ret;
 271
 272         ret = WIMLIB_ERR_NOMEM;
 273         blob = new_blob_descriptor();
 274         if (!blob)
 275                 goto out;
 276
 277         ret = read_pwm_blob_header(pwm, blob->hash, &reshdr, NULL);
 278         if (ret)
 279                 goto out;
 280
 281         ret = WIMLIB_ERR_INVALID_PIPABLE_WIM;
 282         if (!(reshdr.flags & WIM_RESHDR_FLAG_METADATA)) {
 283                 ERROR("Expected metadata resource, but found non-metadata "
 284                       "resource");
 285                 goto out;
 286         }
 287
 288         ret = WIMLIB_ERR_NOMEM;
 289         rdesc = MALLOC(sizeof(*rdesc));
 290         if (!rdesc)
 291                 goto out;
 292
 293         wim_reshdr_to_desc_and_blob(&reshdr, pwm, rdesc, blob);
 294         pwm->refcnt++;
 295
 296         ret = WIMLIB_ERR_NOMEM;
 297         pwm->image_metadata[image - 1] = new_unloaded_image_metadata(blob);
 298         if (!pwm->image_metadata[image - 1])
 299                 goto out;
 300         blob = NULL;
 301
 302         /* If the metadata resource is for the image being extracted, then parse
 303          * it and save the metadata in memory.  Otherwise, skip over it.  */
 304         if (is_needed)
 305                 ret = select_wim_image(pwm, image);
 306         else
 307                 ret = skip_wim_resource(rdesc);
 308 out:
 309         free_blob_descriptor(blob);
 310         return ret;
 311 }
 312
 313 /* Creates a temporary file opened for writing.  The open file descriptor is
 314  * returned in @fd_ret and its name is returned in @name_ret (dynamically
 315  * allocated).  */
 316 static int
 317 create_temporary_file(struct filedes *fd_ret, tchar **name_ret)
 318 {
 319         tchar *name;
 320         int raw_fd;
 321
 322 #ifdef __WIN32__
 323 retry:
 324         name = _wtempnam(NULL, L"wimlib");
 325         if (!name) {
 326                 ERROR_WITH_ERRNO("Failed to create temporary filename");
 327                 return WIMLIB_ERR_NOMEM;
 328         }
 329         raw_fd = _wopen(name, O_WRONLY | O_CREAT | O_EXCL | O_BINARY |
 330                         _O_SHORT_LIVED, 0600);
 331         if (raw_fd < 0 && errno == EEXIST) {
 332                 FREE(name);
 333                 goto retry;
 334         }
 335 #else /* __WIN32__ */
 336         const char *tmpdir = getenv("TMPDIR");
 337         if (!tmpdir)
 338                 tmpdir = P_tmpdir;
 339         name = MALLOC(strlen(tmpdir) + 1 + 6 + 6 + 1);
 340         if (!name)
 341                 return WIMLIB_ERR_NOMEM;
 342         sprintf(name, "%s/wimlibXXXXXX", tmpdir);
 343         raw_fd = mkstemp(name);
 344 #endif /* !__WIN32__ */
 345
 346         if (raw_fd < 0) {
 347                 ERROR_WITH_ERRNO("Failed to create temporary file "
 348                                  "\"%"TS"\"", name);
 349                 FREE(name);
 350                 return WIMLIB_ERR_OPEN;
 351         }
 352
 353         filedes_init(fd_ret, raw_fd);
 354         *name_ret = name;
 355         return 0;
 356 }
 357
 358 static int
 359 begin_extract_blob_wrapper(struct blob_descriptor *blob, void *_ctx)
 360 {
 361         struct apply_ctx *ctx = _ctx;
 362
 363         ctx->cur_blob = blob;
 364         ctx->cur_blob_offset = 0;
 365
 366         if (unlikely(blob->out_refcnt > MAX_OPEN_FILES))
 367                 return create_temporary_file(&ctx->tmpfile_fd, &ctx->tmpfile_name);
 368
 369         return call_begin_blob(blob, ctx->saved_cbs);
 370 }
 371
 372 static int
 373 extract_chunk_wrapper(const void *chunk, size_t size, void *_ctx)
 374 {
 375         struct apply_ctx *ctx = _ctx;
 376         union wimlib_progress_info *progress = &ctx->progress;
 377         int ret;
 378
 379         ctx->cur_blob_offset += size;
 380
 381         if (likely(ctx->supported_features.hard_links)) {
 382                 progress->extract.completed_bytes +=
 383                         (u64)size * ctx->cur_blob->out_refcnt;
 384                 if (ctx->cur_blob_offset == ctx->cur_blob->size)
 385                         progress->extract.completed_streams += ctx->cur_blob->out_refcnt;
 386         } else {
 387                 const struct blob_extraction_target *targets =
 388                         blob_extraction_targets(ctx->cur_blob);
 389                 for (u32 i = 0; i < ctx->cur_blob->out_refcnt; i++) {
 390                         const struct wim_inode *inode = targets[i].inode;
 391                         const struct wim_dentry *dentry;
 392
 393                         inode_for_each_extraction_alias(dentry, inode) {
 394                                 progress->extract.completed_bytes += size;
 395                                 if (ctx->cur_blob_offset == ctx->cur_blob->size)
 396                                         progress->extract.completed_streams++;
 397                         }
 398                 }
 399         }
 400         if (progress->extract.completed_bytes >= ctx->next_progress) {
 401
 402                 ret = extract_progress(ctx, WIMLIB_PROGRESS_MSG_EXTRACT_STREAMS);
 403                 if (ret)
 404                         return ret;
 405
 406                 set_next_progress(progress->extract.completed_bytes,
 407                                   progress->extract.total_bytes,
 408                                   &ctx->next_progress);
 409         }
 410
 411         if (unlikely(filedes_valid(&ctx->tmpfile_fd))) {
 412                 /* Just extracting to temporary file for now.  */
 413                 ret = full_write(&ctx->tmpfile_fd, chunk, size);
 414                 if (ret) {
 415                         ERROR_WITH_ERRNO("Error writing data to "
 416                                          "temporary file \"%"TS"\"",
 417                                          ctx->tmpfile_name);
 418                 }
 419                 return ret;
 420         }
 421
 422         return call_consume_chunk(chunk, size, ctx->saved_cbs);
 423 }
 424
 425 /* Copy the blob's data from the temporary file to each of its targets.
 426  *
 427  * This is executed only in the very uncommon case that a blob is being
 428  * extracted to more than MAX_OPEN_FILES targets!  */
 429 static int
 430 extract_from_tmpfile(const tchar *tmpfile_name,
 431                      const struct blob_descriptor *orig_blob,
 432                      const struct read_blob_callbacks *cbs)
 433 {
 434         struct blob_descriptor tmpfile_blob;
 435         const struct blob_extraction_target *targets = blob_extraction_targets(orig_blob);
 436         int ret;
 437
 438         memcpy(&tmpfile_blob, orig_blob, sizeof(struct blob_descriptor));
 439         tmpfile_blob.blob_location = BLOB_IN_FILE_ON_DISK;
 440         tmpfile_blob.file_on_disk = (tchar *)tmpfile_name;
 441         tmpfile_blob.out_refcnt = 1;
 442
 443         for (u32 i = 0; i < orig_blob->out_refcnt; i++) {
 444                 tmpfile_blob.inline_blob_extraction_targets[0] = targets[i];
 445                 ret = read_blob_with_cbs(&tmpfile_blob, cbs);
 446                 if (ret)
 447                         return ret;
 448         }
 449         return 0;
 450 }
 451
 452 static int
 453 end_extract_blob_wrapper(struct blob_descriptor *blob, int status, void *_ctx)
 454 {
 455         struct apply_ctx *ctx = _ctx;
 456
 457         if (unlikely(filedes_valid(&ctx->tmpfile_fd))) {
 458                 filedes_close(&ctx->tmpfile_fd);
 459                 if (!status)
 460                         status = extract_from_tmpfile(ctx->tmpfile_name, blob,
 461                                                       ctx->saved_cbs);
 462                 filedes_invalidate(&ctx->tmpfile_fd);
 463                 tunlink(ctx->tmpfile_name);
 464                 FREE(ctx->tmpfile_name);
 465                 return status;
 466         }
 467
 468         return call_end_blob(blob, status, ctx->saved_cbs);
 469 }
 470
 471 /*
 472  * Read the list of blobs to extract and feed their data into the specified
 473  * callback functions.
 474  *
 475  * This handles checksumming each blob.
 476  *
 477  * This also handles sending WIMLIB_PROGRESS_MSG_EXTRACT_STREAMS.
 478  *
 479  * This also works if the WIM is being read from a pipe.
 480  *
 481  * This also will split up blobs that will need to be extracted to more than
 482  * MAX_OPEN_FILES locations, as measured by the 'out_refcnt' of each blob.
 483  * Therefore, the apply_operations implementation need not worry about running
 484  * out of file descriptors, unless it might open more than one file descriptor
 485  * per 'blob_extraction_target' (e.g. Win32 currently might because the
 486  * destination file system might not support hard links).
 487  */
 488 int
 489 extract_blob_list(struct apply_ctx *ctx, const struct read_blob_callbacks *cbs)
 490 {
 491         struct read_blob_callbacks wrapper_cbs = {
 492                 .begin_blob     = begin_extract_blob_wrapper,
 493                 .consume_chunk  = extract_chunk_wrapper,
 494                 .end_blob       = end_extract_blob_wrapper,
 495                 .ctx            = ctx,
 496         };
 497         ctx->saved_cbs = cbs;
 498         if (ctx->extract_flags & WIMLIB_EXTRACT_FLAG_FROM_PIPE) {
 499                 return read_blobs_from_pipe(ctx, &wrapper_cbs);
 500         } else {
 501                 return read_blob_list(&ctx->blob_list,
 502                                       offsetof(struct blob_descriptor,
 503                                                extraction_list),
 504                                       &wrapper_cbs, VERIFY_BLOB_HASHES);
 505         }
 506 }
 507
 508 /* Extract a WIM dentry to standard output.
 509  *
 510  * This obviously doesn't make sense in all cases.  We return an error if the
 511  * dentry does not correspond to a regular file.  Otherwise we extract the
 512  * unnamed data stream only.  */
 513 static int
 514 extract_dentry_to_stdout(struct wim_dentry *dentry,
 515                          const struct blob_table *blob_table)
 516 {
 517         struct wim_inode *inode = dentry->d_inode;
 518         struct blob_descriptor *blob;
 519         struct filedes _stdout;
 520
 521         if (inode->i_attributes & (FILE_ATTRIBUTE_REPARSE_POINT |
 522                                    FILE_ATTRIBUTE_DIRECTORY |
 523                                    FILE_ATTRIBUTE_ENCRYPTED))
 524         {
 525                 ERROR("\"%"TS"\" is not a regular file and therefore cannot be "
 526                       "extracted to standard output", dentry_full_path(dentry));
 527                 return WIMLIB_ERR_NOT_A_REGULAR_FILE;
 528         }
 529
 530         blob = inode_get_blob_for_unnamed_data_stream(inode, blob_table);
 531         if (!blob) {
 532                 const u8 *hash = inode_get_hash_of_unnamed_data_stream(inode);
 533                 if (!is_zero_hash(hash))
 534                         return blob_not_found_error(inode, hash);
 535                 return 0;
 536         }
 537
 538         filedes_init(&_stdout, STDOUT_FILENO);
 539         return extract_blob_to_fd(blob, &_stdout);
 540 }
 541
 542 static int
 543 extract_dentries_to_stdout(struct wim_dentry **dentries, size_t num_dentries,
 544                            const struct blob_table *blob_table)
 545 {
 546         for (size_t i = 0; i < num_dentries; i++) {
 547                 int ret = extract_dentry_to_stdout(dentries[i], blob_table);
 548                 if (ret)
 549                         return ret;
 550         }
 551         return 0;
 552 }
 553
 554 /**********************************************************************/
 555
 556 /*
 557  * Removes duplicate dentries from the array.
 558  *
 559  * Returns the new number of dentries, packed at the front of the array.
 560  */
 561 static size_t
 562 remove_duplicate_trees(struct wim_dentry **trees, size_t num_trees)
 563 {
 564         size_t i, j = 0;
 565         for (i = 0; i < num_trees; i++) {
 566                 if (!trees[i]->d_tmp_flag) {
 567                         /* Found distinct dentry.  */
 568                         trees[i]->d_tmp_flag = 1;
 569                         trees[j++] = trees[i];
 570                 }
 571         }
 572         for (i = 0; i < j; i++)
 573                 trees[i]->d_tmp_flag = 0;
 574         return j;
 575 }
 576
 577 /*
 578  * Remove dentries that are descendants of other dentries in the array.
 579  *
 580  * Returns the new number of dentries, packed at the front of the array.
 581  */
 582 static size_t
 583 remove_contained_trees(struct wim_dentry **trees, size_t num_trees)
 584 {
 585         size_t i, j = 0;
 586         for (i = 0; i < num_trees; i++)
 587                 trees[i]->d_tmp_flag = 1;
 588         for (i = 0; i < num_trees; i++) {
 589                 struct wim_dentry *d = trees[i];
 590                 while (!dentry_is_root(d)) {
 591                         d = d->d_parent;
 592                         if (d->d_tmp_flag)
 593                                 goto tree_contained;
 594                 }
 595                 trees[j++] = trees[i];
 596                 continue;
 597
 598         tree_contained:
 599                 trees[i]->d_tmp_flag = 0;
 600         }
 601
 602         for (i = 0; i < j; i++)
 603                 trees[i]->d_tmp_flag = 0;
 604         return j;
 605 }
 606
 607 static int
 608 dentry_append_to_list(struct wim_dentry *dentry, void *_dentry_list)
 609 {
 610         struct list_head *dentry_list = _dentry_list;
 611         list_add_tail(&dentry->d_extraction_list_node, dentry_list);
 612         return 0;
 613 }
 614
 615 static void
 616 dentry_reset_extraction_list_node(struct wim_dentry *dentry)
 617 {
 618         dentry->d_extraction_list_node = (struct list_head){NULL, NULL};
 619 }
 620
 621 static int
 622 dentry_delete_from_list(struct wim_dentry *dentry, void *_ignore)
 623 {
 624         if (will_extract_dentry(dentry)) {
 625                 list_del(&dentry->d_extraction_list_node);
 626                 dentry_reset_extraction_list_node(dentry);
 627         }
 628         return 0;
 629 }
 630
 631 /*
 632  * Build the preliminary list of dentries to be extracted.
 633  *
 634  * The list maintains the invariant that if d1 and d2 are in the list and d1 is
 635  * an ancestor of d2, then d1 appears before d2 in the list.
 636  */
 637 static void
 638 build_dentry_list(struct list_head *dentry_list, struct wim_dentry **trees,
 639                   size_t num_trees, bool add_ancestors)
 640 {
 641         INIT_LIST_HEAD(dentry_list);
 642
 643         /* Add the trees recursively.  */
 644         for (size_t i = 0; i < num_trees; i++)
 645                 for_dentry_in_tree(trees[i], dentry_append_to_list, dentry_list);
 646
 647         /* If requested, add ancestors of the trees.  */
 648         if (add_ancestors) {
 649                 for (size_t i = 0; i < num_trees; i++) {
 650                         struct wim_dentry *dentry = trees[i];
 651                         struct wim_dentry *ancestor;
 652                         struct list_head *place_after;
 653
 654                         if (dentry_is_root(dentry))
 655                                 continue;
 656
 657                         place_after = dentry_list;
 658                         ancestor = dentry;
 659                         do {
 660                                 ancestor = ancestor->d_parent;
 661                                 if (will_extract_dentry(ancestor)) {
 662                                         place_after = &ancestor->d_extraction_list_node;
 663                                         break;
 664                                 }
 665                         } while (!dentry_is_root(ancestor));
 666
 667                         ancestor = dentry;
 668                         do {
 669                                 ancestor = ancestor->d_parent;
 670                                 if (will_extract_dentry(ancestor))
 671                                         break;
 672                                 list_add(&ancestor->d_extraction_list_node, place_after);
 673                         } while (!dentry_is_root(ancestor));
 674                 }
 675         }
 676 }
 677
 678 static void
 679 destroy_dentry_list(struct list_head *dentry_list)
 680 {
 681         struct wim_dentry *dentry, *tmp;
 682         struct wim_inode *inode;
 683
 684         list_for_each_entry_safe(dentry, tmp, dentry_list, d_extraction_list_node) {
 685                 inode = dentry->d_inode;
 686                 dentry_reset_extraction_list_node(dentry);
 687                 inode->i_visited = 0;
 688                 inode->i_can_externally_back = 0;
 689                 if ((void *)dentry->d_extraction_name != (void *)dentry->d_name)
 690                         FREE(dentry->d_extraction_name);
 691                 dentry->d_extraction_name = NULL;
 692                 dentry->d_extraction_name_nchars = 0;
 693         }
 694 }
 695
 696 static void
 697 destroy_blob_list(struct list_head *blob_list)
 698 {
 699         struct blob_descriptor *blob;
 700
 701         list_for_each_entry(blob, blob_list, extraction_list)
 702                 if (blob->out_refcnt > ARRAY_LEN(blob->inline_blob_extraction_targets))
 703                         FREE(blob->blob_extraction_targets);
 704 }
 705
 706 #ifdef __WIN32__
 707 static const utf16lechar replacement_char = cpu_to_le16(0xfffd);
 708 #else
 709 static const utf16lechar replacement_char = cpu_to_le16('?');
 710 #endif
 711
 712 static bool
 713 file_name_valid(utf16lechar *name, size_t num_chars, bool fix)
 714 {
 715         size_t i;
 716
 717         if (num_chars == 0)
 718                 return true;
 719         for (i = 0; i < num_chars; i++) {
 720                 switch (le16_to_cpu(name[i])) {
 721         #ifdef __WIN32__
 722                 case '\x01'...'\x1F':
 723                 case '\\':
 724                 case ':':
 725                 case '*':
 726                 case '?':
 727                 case '"':
 728                 case '<':
 729                 case '>':
 730                 case '|':
 731         #endif
 732                 case '/':
 733                 case '\0':
 734                         if (fix)
 735                                 name[i] = replacement_char;
 736                         else
 737                                 return false;
 738                 }
 739         }
 740
 741         return true;
 742 }
 743
 744 static int
 745 dentry_calculate_extraction_name(struct wim_dentry *dentry,
 746                                  struct apply_ctx *ctx)
 747 {
 748         int ret;
 749
 750         if (dentry_is_root(dentry))
 751                 return 0;
 752
 753 #ifdef WITH_NTFS_3G
 754         if (ctx->extract_flags & WIMLIB_EXTRACT_FLAG_NTFS) {
 755                 dentry->d_extraction_name = dentry->d_name;
 756                 dentry->d_extraction_name_nchars = dentry->d_name_nbytes /
 757                                                    sizeof(utf16lechar);
 758                 return 0;
 759         }
 760 #endif
 761
 762         if (!ctx->supported_features.case_sensitive_filenames) {
 763                 struct wim_dentry *other;
 764                 dentry_for_each_ci_match(other, dentry) {
 765                         if (will_extract_dentry(other)) {
 766                                 if (ctx->extract_flags &
 767                                     WIMLIB_EXTRACT_FLAG_ALL_CASE_CONFLICTS) {
 768                                         WARNING("\"%"TS"\" has the same "
 769                                                 "case-insensitive name as "
 770                                                 "\"%"TS"\"; extracting "
 771                                                 "dummy name instead",
 772                                                 dentry_full_path(dentry),
 773                                                 dentry_full_path(other));
 774                                         goto out_replace;
 775                                 } else {
 776                                         WARNING("Not extracting \"%"TS"\": "
 777                                                 "has same case-insensitive "
 778                                                 "name as \"%"TS"\"",
 779                                                 dentry_full_path(dentry),
 780                                                 dentry_full_path(other));
 781                                         goto skip_dentry;
 782                                 }
 783                         }
 784                 }
 785         }
 786
 787         if (file_name_valid(dentry->d_name, dentry->d_name_nbytes / 2, false)) {
 788                 size_t nbytes = 0;
 789                 ret = utf16le_get_tstr(dentry->d_name,
 790                                        dentry->d_name_nbytes,
 791                                        (const tchar **)&dentry->d_extraction_name,
 792                                        &nbytes);
 793                 dentry->d_extraction_name_nchars = nbytes / sizeof(tchar);
 794                 return ret;
 795         } else {
 796                 if (ctx->extract_flags & WIMLIB_EXTRACT_FLAG_REPLACE_INVALID_FILENAMES)
 797                 {
 798                         WARNING("\"%"TS"\" has an invalid filename "
 799                                 "that is not supported on this platform; "
 800                                 "extracting dummy name instead",
 801                                 dentry_full_path(dentry));
 802                         goto out_replace;
 803                 } else {
 804                         WARNING("Not extracting \"%"TS"\": has an invalid filename "
 805                                 "that is not supported on this platform",
 806                                 dentry_full_path(dentry));
 807                         goto skip_dentry;
 808                 }
 809         }
 810
 811 out_replace:
 812         {
 813                 utf16lechar utf16_name_copy[dentry->d_name_nbytes / 2];
 814
 815                 memcpy(utf16_name_copy, dentry->d_name, dentry->d_name_nbytes);
 816                 file_name_valid(utf16_name_copy, dentry->d_name_nbytes / 2, true);
 817
 818                 const tchar *tchar_name;
 819                 size_t tchar_nchars;
 820
 821                 ret = utf16le_get_tstr(utf16_name_copy,
 822                                        dentry->d_name_nbytes,
 823                                        &tchar_name, &tchar_nchars);
 824                 if (ret)
 825                         return ret;
 826
 827                 tchar_nchars /= sizeof(tchar);
 828
 829                 size_t fixed_name_num_chars = tchar_nchars;
 830                 tchar fixed_name[tchar_nchars + 50];
 831
 832                 tmemcpy(fixed_name, tchar_name, tchar_nchars);
 833                 fixed_name_num_chars += tsprintf(fixed_name + tchar_nchars,
 834                                                  T(" (invalid filename #%lu)"),
 835                                                  ++ctx->invalid_sequence);
 836
 837                 utf16le_put_tstr(tchar_name);
 838
 839                 dentry->d_extraction_name = TSTRDUP(fixed_name);
 840                 if (!dentry->d_extraction_name)
 841                         return WIMLIB_ERR_NOMEM;
 842                 dentry->d_extraction_name_nchars = fixed_name_num_chars;
 843         }
 844         return 0;
 845
 846 skip_dentry:
 847         for_dentry_in_tree(dentry, dentry_delete_from_list, NULL);
 848         return 0;
 849 }
 850
 851 /*
 852  * Calculate the actual filename component at which each WIM dentry will be
 853  * extracted, with special handling for dentries that are unsupported by the
 854  * extraction backend or have invalid names.
 855  *
 856  * ctx->supported_features must be filled in.
 857  *
 858  * Possible error codes: WIMLIB_ERR_NOMEM, WIMLIB_ERR_INVALID_UTF16_STRING
 859  */
 860 static int
 861 dentry_list_calculate_extraction_names(struct list_head *dentry_list,
 862                                        struct apply_ctx *ctx)
 863 {
 864         struct list_head *prev, *cur;
 865
 866         /* Can't use list_for_each_entry() because a call to
 867          * dentry_calculate_extraction_name() may delete the current dentry and
 868          * its children from the list.  */
 869
 870         prev = dentry_list;
 871         for (;;) {
 872                 struct wim_dentry *dentry;
 873                 int ret;
 874
 875                 cur = prev->next;
 876                 if (cur == dentry_list)
 877                         break;
 878
 879                 dentry = list_entry(cur, struct wim_dentry, d_extraction_list_node);
 880
 881                 ret = dentry_calculate_extraction_name(dentry, ctx);
 882                 if (ret)
 883                         return ret;
 884
 885                 if (prev->next == cur)
 886                         prev = cur;
 887                 else
 888                         ; /* Current dentry and its children (which follow in
 889                              the list) were deleted.  prev stays the same.  */
 890         }
 891         return 0;
 892 }
 893
 894 static int
 895 dentry_resolve_streams(struct wim_dentry *dentry, int extract_flags,
 896                        struct blob_table *blob_table)
 897 {
 898         struct wim_inode *inode = dentry->d_inode;
 899         struct blob_descriptor *blob;
 900         int ret;
 901         bool force = false;
 902
 903         /* Special case:  when extracting from a pipe, the WIM blob table is
 904          * initially empty, so "resolving" an inode's streams is initially not
 905          * possible.  However, we still need to keep track of which blobs,
 906          * identified by SHA-1 message digests, need to be extracted, so we
 907          * "resolve" the inode's streams anyway by allocating a 'struct
 908          * blob_descriptor' for each one.  */
 909         if (extract_flags & WIMLIB_EXTRACT_FLAG_FROM_PIPE)
 910                 force = true;
 911         ret = inode_resolve_streams(inode, blob_table, force);
 912         if (ret)
 913                 return ret;
 914         for (unsigned i = 0; i < inode->i_num_streams; i++) {
 915                 blob = stream_blob_resolved(&inode->i_streams[i]);
 916                 if (blob)
 917                         blob->out_refcnt = 0;
 918         }
 919         return 0;
 920 }
 921
 922 /*
 923  * For each dentry to be extracted, resolve all streams in the corresponding
 924  * inode and set 'out_refcnt' in all referenced blob_descriptors to 0.
 925  *
 926  * Possible error codes: WIMLIB_ERR_RESOURCE_NOT_FOUND, WIMLIB_ERR_NOMEM.
 927  */
 928 static int
 929 dentry_list_resolve_streams(struct list_head *dentry_list,
 930                             struct apply_ctx *ctx)
 931 {
 932         struct wim_dentry *dentry;
 933         int ret;
 934
 935         list_for_each_entry(dentry, dentry_list, d_extraction_list_node) {
 936                 ret = dentry_resolve_streams(dentry,
 937                                              ctx->extract_flags,
 938                                              ctx->wim->blob_table);
 939                 if (ret)
 940                         return ret;
 941         }
 942         return 0;
 943 }
 944
 945 static int
 946 ref_stream(struct wim_inode_stream *strm, struct wim_dentry *dentry,
 947            struct apply_ctx *ctx)
 948 {
 949         struct wim_inode *inode = dentry->d_inode;
 950         struct blob_descriptor *blob = stream_blob_resolved(strm);
 951         struct blob_extraction_target *targets;
 952
 953         if (!blob)
 954                 return 0;
 955
 956         /* Tally the size only for each actual extraction of the stream (not
 957          * additional hard links to the inode).  */
 958         if (inode->i_visited && ctx->supported_features.hard_links)
 959                 return 0;
 960
 961         ctx->progress.extract.total_bytes += blob->size;
 962         ctx->progress.extract.total_streams++;
 963
 964         if (inode->i_visited)
 965                 return 0;
 966
 967         /* Add each blob to 'ctx->blob_list' only one time, regardless of how
 968          * many extraction targets it will have.  */
 969         if (blob->out_refcnt == 0) {
 970                 list_add_tail(&blob->extraction_list, &ctx->blob_list);
 971                 ctx->num_blobs_remaining++;
 972         }
 973
 974         /* Set this stream as an extraction target of 'blob'.  */
 975
 976         if (blob->out_refcnt < ARRAY_LEN(blob->inline_blob_extraction_targets)) {
 977                 targets = blob->inline_blob_extraction_targets;
 978         } else {
 979                 struct blob_extraction_target *prev_targets;
 980                 size_t alloc_blob_extraction_targets;
 981
 982                 if (blob->out_refcnt == ARRAY_LEN(blob->inline_blob_extraction_targets)) {
 983                         prev_targets = NULL;
 984                         alloc_blob_extraction_targets = ARRAY_LEN(blob->inline_blob_extraction_targets);
 985                 } else {
 986                         prev_targets = blob->blob_extraction_targets;
 987                         alloc_blob_extraction_targets = blob->alloc_blob_extraction_targets;
 988                 }
 989
 990                 if (blob->out_refcnt == alloc_blob_extraction_targets) {
 991                         alloc_blob_extraction_targets *= 2;
 992                         targets = REALLOC(prev_targets,
 993                                           alloc_blob_extraction_targets *
 994                                           sizeof(targets[0]));
 995                         if (!targets)
 996                                 return WIMLIB_ERR_NOMEM;
 997                         if (!prev_targets) {
 998                                 memcpy(targets,
 999                                        blob->inline_blob_extraction_targets,
1000                                        sizeof(blob->inline_blob_extraction_targets));
1001                         }
1002                         blob->blob_extraction_targets = targets;
1003                         blob->alloc_blob_extraction_targets = alloc_blob_extraction_targets;
1004                 }
1005                 targets = blob->blob_extraction_targets;
1006         }
1007         targets[blob->out_refcnt].inode = inode;
1008         targets[blob->out_refcnt].stream = strm;
1009         blob->out_refcnt++;
1010         return 0;
1011 }
1012
1013 static int
1014 ref_stream_if_needed(struct wim_dentry *dentry, struct wim_inode *inode,
1015                      struct wim_inode_stream *strm, struct apply_ctx *ctx)
1016 {
1017         bool need_stream = false;
1018         switch (strm->stream_type) {
1019         case STREAM_TYPE_DATA:
1020                 if (stream_is_named(strm)) {
1021                         /* Named data stream  */
1022                         if (ctx->supported_features.named_data_streams)
1023                                 need_stream = true;
1024                 } else if (!(inode->i_attributes & (FILE_ATTRIBUTE_DIRECTORY |
1025                                                     FILE_ATTRIBUTE_ENCRYPTED))
1026                            && !(inode_is_symlink(inode)
1027                                 && !ctx->supported_features.reparse_points
1028                                 && ctx->supported_features.symlink_reparse_points))
1029                 {
1030                         /*
1031                          * Unnamed data stream.  Skip if any of the following is true:
1032                          *
1033                          * - file is a directory
1034                          * - file is encrypted
1035                          * - backend needs to create the file as UNIX symlink
1036                          * - backend will extract the stream as externally
1037                          *   backed from the WIM archive itself
1038                          */
1039                         if (ctx->apply_ops->will_back_from_wim) {
1040                                 int ret = (*ctx->apply_ops->will_back_from_wim)(dentry, ctx);
1041                                 if (ret > 0) /* Error?  */
1042                                         return ret;
1043                                 if (ret < 0) /* Won't externally back?  */
1044                                         need_stream = true;
1045                         } else {
1046                                 need_stream = true;
1047                         }
1048                 }
1049                 break;
1050         case STREAM_TYPE_REPARSE_POINT:
1051                 wimlib_assert(inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT);
1052                 if (ctx->supported_features.reparse_points ||
1053                     (inode_is_symlink(inode) &&
1054                      ctx->supported_features.symlink_reparse_points))
1055                         need_stream = true;
1056                 break;
1057         case STREAM_TYPE_EFSRPC_RAW_DATA:
1058                 wimlib_assert(inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED);
1059                 if (inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY) {
1060                         if (ctx->supported_features.encrypted_directories)
1061                                 need_stream = true;
1062                 } else {
1063                         if (ctx->supported_features.encrypted_files)
1064                                 need_stream = true;
1065                 }
1066                 break;
1067         }
1068         if (need_stream)
1069                 return ref_stream(strm, dentry, ctx);
1070         return 0;
1071 }
1072
1073 static int
1074 dentry_ref_streams(struct wim_dentry *dentry, struct apply_ctx *ctx)
1075 {
1076         struct wim_inode *inode = dentry->d_inode;
1077         for (unsigned i = 0; i < inode->i_num_streams; i++) {
1078                 int ret = ref_stream_if_needed(dentry, inode,
1079                                                &inode->i_streams[i], ctx);
1080                 if (ret)
1081                         return ret;
1082         }
1083         inode->i_visited = 1;
1084         return 0;
1085 }
1086
1087 /*
1088  * Given a list of dentries to be extracted, build the list of blobs that need
1089  * to be extracted, and for each blob determine the streams to which that blob
1090  * will be extracted.
1091  *
1092  * This also initializes the extract progress info with byte and blob
1093  * information.
1094  *
1095  * ctx->supported_features must be filled in.
1096  */
1097 static int
1098 dentry_list_ref_streams(struct list_head *dentry_list, struct apply_ctx *ctx)
1099 {
1100         struct wim_dentry *dentry;
1101         int ret;
1102
1103         list_for_each_entry(dentry, dentry_list, d_extraction_list_node) {
1104                 ret = dentry_ref_streams(dentry, ctx);
1105                 if (ret)
1106                         return ret;
1107         }
1108         list_for_each_entry(dentry, dentry_list, d_extraction_list_node)
1109                 dentry->d_inode->i_visited = 0;
1110         return 0;
1111 }
1112
1113 static void
1114 dentry_list_build_inode_alias_lists(struct list_head *dentry_list)
1115 {
1116         struct wim_dentry *dentry;
1117
1118         list_for_each_entry(dentry, dentry_list, d_extraction_list_node)
1119                 dentry->d_inode->i_first_extraction_alias = NULL;
1120
1121         list_for_each_entry(dentry, dentry_list, d_extraction_list_node) {
1122                 dentry->d_next_extraction_alias = dentry->d_inode->i_first_extraction_alias;
1123                 dentry->d_inode->i_first_extraction_alias = dentry;
1124         }
1125 }
1126
1127 static void
1128 inode_tally_features(const struct wim_inode *inode,
1129                      struct wim_features *features)
1130 {
1131         if (inode->i_attributes & FILE_ATTRIBUTE_READONLY)
1132                 features->readonly_files++;
1133         if (inode->i_attributes & FILE_ATTRIBUTE_HIDDEN)
1134                 features->hidden_files++;
1135         if (inode->i_attributes & FILE_ATTRIBUTE_SYSTEM)
1136                 features->system_files++;
1137         if (inode->i_attributes & FILE_ATTRIBUTE_ARCHIVE)
1138                 features->archive_files++;
1139         if (inode->i_attributes & FILE_ATTRIBUTE_COMPRESSED)
1140                 features->compressed_files++;
1141         if (inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED) {
1142                 if (inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY)
1143                         features->encrypted_directories++;
1144                 else
1145                         features->encrypted_files++;
1146         }
1147         if (inode->i_attributes & FILE_ATTRIBUTE_NOT_CONTENT_INDEXED)
1148                 features->not_context_indexed_files++;
1149         if (inode->i_attributes & FILE_ATTRIBUTE_SPARSE_FILE)
1150                 features->sparse_files++;
1151         if (inode_has_named_data_stream(inode))
1152                 features->named_data_streams++;
1153         if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
1154                 features->reparse_points++;
1155                 if (inode_is_symlink(inode))
1156                         features->symlink_reparse_points++;
1157                 else
1158                         features->other_reparse_points++;
1159         }
1160         if (inode_has_security_descriptor(inode))
1161                 features->security_descriptors++;
1162         if (inode_has_unix_data(inode))
1163                 features->unix_data++;
1164         if (inode_has_object_id(inode))
1165                 features->object_ids++;
1166 }
1167
1168 /* Tally features necessary to extract a dentry and the corresponding inode.  */
1169 static void
1170 dentry_tally_features(struct wim_dentry *dentry, struct wim_features *features)
1171 {
1172         struct wim_inode *inode = dentry->d_inode;
1173
1174         if (dentry_has_short_name(dentry))
1175                 features->short_names++;
1176
1177         if (inode->i_visited) {
1178                 features->hard_links++;
1179         } else {
1180                 inode_tally_features(inode, features);
1181                 inode->i_visited = 1;
1182         }
1183 }
1184
1185 /* Tally the features necessary to extract the specified dentries.  */
1186 static void
1187 dentry_list_get_features(struct list_head *dentry_list,
1188                          struct wim_features *features)
1189 {
1190         struct wim_dentry *dentry;
1191
1192         list_for_each_entry(dentry, dentry_list, d_extraction_list_node)
1193                 dentry_tally_features(dentry, features);
1194
1195         list_for_each_entry(dentry, dentry_list, d_extraction_list_node)
1196                 dentry->d_inode->i_visited = 0;
1197 }
1198
1199 static int
1200 do_feature_check(const struct wim_features *required_features,
1201                  const struct wim_features *supported_features,
1202                  int extract_flags)
1203 {
1204         /* Encrypted files.  */
1205         if (required_features->encrypted_files &&
1206             !supported_features->encrypted_files)
1207                 WARNING("Ignoring EFS-encrypted data of %lu files",
1208                         required_features->encrypted_files);
1209
1210         /* Named data streams.  */
1211         if (required_features->named_data_streams &&
1212             !supported_features->named_data_streams)
1213                 WARNING("Ignoring named data streams of %lu files",
1214                         required_features->named_data_streams);
1215
1216         /* File attributes.  */
1217         if (!(extract_flags & WIMLIB_EXTRACT_FLAG_NO_ATTRIBUTES)) {
1218
1219                 if (required_features->readonly_files &&
1220                     !supported_features->readonly_files)
1221                         WARNING("Ignoring FILE_ATTRIBUTE_READONLY of %lu files",
1222                                 required_features->readonly_files);
1223
1224                 if (required_features->hidden_files &&
1225                     !supported_features->hidden_files)
1226                         WARNING("Ignoring FILE_ATTRIBUTE_HIDDEN of %lu files",
1227                                 required_features->hidden_files);
1228
1229                 if (required_features->system_files &&
1230                     !supported_features->system_files)
1231                         WARNING("Ignoring FILE_ATTRIBUTE_SYSTEM of %lu files",
1232                                 required_features->system_files);
1233
1234                 /* Note: Don't bother the user about FILE_ATTRIBUTE_ARCHIVE.
1235                  * We're an archive program, so theoretically we can do what we
1236                  * want with it.  */
1237
1238                 if (required_features->compressed_files &&
1239                     !supported_features->compressed_files)
1240                         WARNING("Ignoring FILE_ATTRIBUTE_COMPRESSED of %lu files",
1241                                 required_features->compressed_files);
1242
1243                 if (required_features->not_context_indexed_files &&
1244                     !supported_features->not_context_indexed_files)
1245                         WARNING("Ignoring FILE_ATTRIBUTE_NOT_CONTENT_INDEXED of %lu files",
1246                                 required_features->not_context_indexed_files);
1247
1248                 if (required_features->sparse_files &&
1249                     !supported_features->sparse_files)
1250                         WARNING("Ignoring FILE_ATTRIBUTE_SPARSE_FILE of %lu files",
1251                                 required_features->sparse_files);
1252
1253                 if (required_features->encrypted_directories &&
1254                     !supported_features->encrypted_directories)
1255                         WARNING("Ignoring FILE_ATTRIBUTE_ENCRYPTED of %lu directories",
1256                                 required_features->encrypted_directories);
1257         }
1258
1259         /* Hard links.  */
1260         if (required_features->hard_links && !supported_features->hard_links)
1261                 WARNING("Extracting %lu hard links as independent files",
1262                         required_features->hard_links);
1263
1264         /* Symbolic links and reparse points.  */
1265         if ((extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_SYMLINKS) &&
1266             required_features->symlink_reparse_points &&
1267             !supported_features->symlink_reparse_points &&
1268             !supported_features->reparse_points)
1269         {
1270                 ERROR("Extraction backend does not support symbolic links!");
1271                 return WIMLIB_ERR_UNSUPPORTED;
1272         }
1273         if (required_features->reparse_points &&
1274             !supported_features->reparse_points)
1275         {
1276                 if (supported_features->symlink_reparse_points) {
1277                         if (required_features->other_reparse_points) {
1278                                 WARNING("Ignoring reparse data of %lu non-symlink/junction files",
1279                                         required_features->other_reparse_points);
1280                         }
1281                 } else {
1282                         WARNING("Ignoring reparse data of %lu files",
1283                                 required_features->reparse_points);
1284                 }
1285         }
1286
1287         /* Security descriptors.  */
1288         if (((extract_flags & (WIMLIB_EXTRACT_FLAG_STRICT_ACLS |
1289                                WIMLIB_EXTRACT_FLAG_UNIX_DATA))
1290              == WIMLIB_EXTRACT_FLAG_STRICT_ACLS) &&
1291             required_features->security_descriptors &&
1292             !supported_features->security_descriptors)
1293         {
1294                 ERROR("Extraction backend does not support security descriptors!");
1295                 return WIMLIB_ERR_UNSUPPORTED;
1296         }
1297         if (!(extract_flags & WIMLIB_EXTRACT_FLAG_NO_ACLS) &&
1298             required_features->security_descriptors &&
1299             !supported_features->security_descriptors)
1300                 WARNING("Ignoring Windows NT security descriptors of %lu files",
1301                         required_features->security_descriptors);
1302
1303         /* UNIX data.  */
1304         if ((extract_flags & WIMLIB_EXTRACT_FLAG_UNIX_DATA) &&
1305             required_features->unix_data && !supported_features->unix_data)
1306         {
1307                 ERROR("Extraction backend does not support UNIX data!");
1308                 return WIMLIB_ERR_UNSUPPORTED;
1309         }
1310
1311         if (required_features->unix_data &&
1312             !(extract_flags & WIMLIB_EXTRACT_FLAG_UNIX_DATA))
1313         {
1314                 WARNING("Ignoring UNIX metadata of %lu files",
1315                         required_features->unix_data);
1316         }
1317
1318         /* Object IDs.  */
1319         if (required_features->object_ids && !supported_features->object_ids) {
1320                 WARNING("Ignoring object IDs of %lu files",
1321                         required_features->object_ids);
1322         }
1323
1324         /* DOS Names.  */
1325         if (required_features->short_names &&
1326             !supported_features->short_names)
1327         {
1328                 if (extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_SHORT_NAMES) {
1329                         ERROR("Extraction backend does not support DOS names!");
1330                         return WIMLIB_ERR_UNSUPPORTED;
1331                 }
1332                 WARNING("Ignoring DOS names of %lu files",
1333                         required_features->short_names);
1334         }
1335
1336         /* Timestamps.  */
1337         if ((extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_TIMESTAMPS) &&
1338             !supported_features->timestamps)
1339         {
1340                 ERROR("Extraction backend does not support timestamps!");
1341                 return WIMLIB_ERR_UNSUPPORTED;
1342         }
1343
1344         return 0;
1345 }
1346
1347 static const struct apply_operations *
1348 select_apply_operations(int extract_flags)
1349 {
1350 #ifdef WITH_NTFS_3G
1351         if (extract_flags & WIMLIB_EXTRACT_FLAG_NTFS)
1352                 return &ntfs_3g_apply_ops;
1353 #endif
1354 #ifdef __WIN32__
1355         return &win32_apply_ops;
1356 #else
1357         return &unix_apply_ops;
1358 #endif
1359 }
1360
1361 static int
1362 extract_trees(WIMStruct *wim, struct wim_dentry **trees, size_t num_trees,
1363               const tchar *target, int extract_flags)
1364 {
1365         const struct apply_operations *ops;
1366         struct apply_ctx *ctx;
1367         int ret;
1368         LIST_HEAD(dentry_list);
1369
1370         if (extract_flags & WIMLIB_EXTRACT_FLAG_TO_STDOUT) {
1371                 ret = extract_dentries_to_stdout(trees, num_trees,
1372                                                  wim->blob_table);
1373                 goto out;
1374         }
1375
1376         num_trees = remove_duplicate_trees(trees, num_trees);
1377         num_trees = remove_contained_trees(trees, num_trees);
1378
1379         ops = select_apply_operations(extract_flags);
1380
1381         if (num_trees > 1 && ops->single_tree_only) {
1382                 ERROR("Extracting multiple directory trees "
1383                       "at once is not supported in %s extraction mode!",
1384                       ops->name);
1385                 ret = WIMLIB_ERR_UNSUPPORTED;
1386                 goto out;
1387         }
1388
1389         ctx = CALLOC(1, ops->context_size);
1390         if (!ctx) {
1391                 ret = WIMLIB_ERR_NOMEM;
1392                 goto out;
1393         }
1394
1395         ctx->wim = wim;
1396         ctx->target = target;
1397         ctx->target_nchars = tstrlen(target);
1398         ctx->extract_flags = extract_flags;
1399         if (ctx->wim->progfunc) {
1400                 ctx->progfunc = ctx->wim->progfunc;
1401                 ctx->progctx = ctx->wim->progctx;
1402                 ctx->progress.extract.image = wim->current_image;
1403                 ctx->progress.extract.extract_flags = (extract_flags &
1404                                                        WIMLIB_EXTRACT_MASK_PUBLIC);
1405                 ctx->progress.extract.wimfile_name = wim->filename;
1406                 ctx->progress.extract.image_name = wimlib_get_image_name(wim,
1407                                                                          wim->current_image);
1408                 ctx->progress.extract.target = target;
1409         }
1410         INIT_LIST_HEAD(&ctx->blob_list);
1411         filedes_invalidate(&ctx->tmpfile_fd);
1412         ctx->apply_ops = ops;
1413
1414         ret = (*ops->get_supported_features)(target, &ctx->supported_features);
1415         if (ret)
1416                 goto out_cleanup;
1417
1418         build_dentry_list(&dentry_list, trees, num_trees,
1419                           !(extract_flags &
1420                             WIMLIB_EXTRACT_FLAG_NO_PRESERVE_DIR_STRUCTURE));
1421
1422         dentry_list_get_features(&dentry_list, &ctx->required_features);
1423
1424         ret = do_feature_check(&ctx->required_features, &ctx->supported_features,
1425                                ctx->extract_flags);
1426         if (ret)
1427                 goto out_cleanup;
1428
1429         ret = dentry_list_calculate_extraction_names(&dentry_list, ctx);
1430         if (ret)
1431                 goto out_cleanup;
1432
1433         if (unlikely(list_empty(&dentry_list))) {
1434                 WARNING("There is nothing to extract!");
1435                 goto out_cleanup;
1436         }
1437
1438         ret = dentry_list_resolve_streams(&dentry_list, ctx);
1439         if (ret)
1440                 goto out_cleanup;
1441
1442         dentry_list_build_inode_alias_lists(&dentry_list);
1443
1444         ret = dentry_list_ref_streams(&dentry_list, ctx);
1445         if (ret)
1446                 goto out_cleanup;
1447
1448         if (extract_flags & WIMLIB_EXTRACT_FLAG_FROM_PIPE) {
1449                 /* When extracting from a pipe, the number of bytes of data to
1450                  * extract can't be determined in the normal way (examining the
1451                  * blob table), since at this point all we have is a set of
1452                  * SHA-1 message digests of blobs that need to be extracted.
1453                  * However, we can get a reasonably accurate estimate by taking
1454                  * <TOTALBYTES> from the corresponding <IMAGE> in the WIM XML
1455                  * data.  This does assume that a full image is being extracted,
1456                  * but currently there is no API for doing otherwise.  (Also,
1457                  * subtract <HARDLINKBYTES> from this if hard links are
1458                  * supported by the extraction mode.)  */
1459                 ctx->progress.extract.total_bytes =
1460                         xml_get_image_total_bytes(wim->xml_info,
1461                                                   wim->current_image);
1462                 if (ctx->supported_features.hard_links) {
1463                         ctx->progress.extract.total_bytes -=
1464                                 xml_get_image_hard_link_bytes(wim->xml_info,
1465                                                               wim->current_image);
1466                 }
1467         }
1468
1469         ret = extract_progress(ctx,
1470                                ((extract_flags & WIMLIB_EXTRACT_FLAG_IMAGEMODE) ?
1471                                        WIMLIB_PROGRESS_MSG_EXTRACT_IMAGE_BEGIN :
1472                                        WIMLIB_PROGRESS_MSG_EXTRACT_TREE_BEGIN));
1473         if (ret)
1474                 goto out_cleanup;
1475
1476         ret = (*ops->extract)(&dentry_list, ctx);
1477         if (ret)
1478                 goto out_cleanup;
1479
1480         if (ctx->progress.extract.completed_bytes <
1481             ctx->progress.extract.total_bytes)
1482         {
1483                 ctx->progress.extract.completed_bytes =
1484                         ctx->progress.extract.total_bytes;
1485                 ret = extract_progress(ctx, WIMLIB_PROGRESS_MSG_EXTRACT_STREAMS);
1486                 if (ret)
1487                         goto out_cleanup;
1488         }
1489
1490         ret = extract_progress(ctx,
1491                                ((extract_flags & WIMLIB_EXTRACT_FLAG_IMAGEMODE) ?
1492                                        WIMLIB_PROGRESS_MSG_EXTRACT_IMAGE_END :
1493                                        WIMLIB_PROGRESS_MSG_EXTRACT_TREE_END));
1494 out_cleanup:
1495         destroy_blob_list(&ctx->blob_list);
1496         destroy_dentry_list(&dentry_list);
1497         FREE(ctx);
1498 out:
1499         return ret;
1500 }
1501
1502 static int
1503 mkdir_if_needed(const tchar *target)
1504 {
1505         if (!tmkdir(target, 0755))
1506                 return 0;
1507
1508         if (errno == EEXIST)
1509                 return 0;
1510
1511 #ifdef __WIN32__
1512         /* _wmkdir() fails with EACCES if called on a drive root directory.  */
1513         if (errno == EACCES)
1514                 return 0;
1515 #endif
1516
1517         ERROR_WITH_ERRNO("Failed to create directory \"%"TS"\"", target);
1518         return WIMLIB_ERR_MKDIR;
1519 }
1520
1521 /* Make sure the extraction flags make sense, and update them if needed.  */
1522 static int
1523 check_extract_flags(const WIMStruct *wim, int *extract_flags_p)
1524 {
1525         int extract_flags = *extract_flags_p;
1526
1527         /* Check for invalid flag combinations  */
1528
1529         if ((extract_flags &
1530              (WIMLIB_EXTRACT_FLAG_NO_ACLS |
1531               WIMLIB_EXTRACT_FLAG_STRICT_ACLS)) == (WIMLIB_EXTRACT_FLAG_NO_ACLS |
1532                                                     WIMLIB_EXTRACT_FLAG_STRICT_ACLS))
1533                 return WIMLIB_ERR_INVALID_PARAM;
1534
1535         if ((extract_flags &
1536              (WIMLIB_EXTRACT_FLAG_RPFIX |
1537               WIMLIB_EXTRACT_FLAG_NORPFIX)) == (WIMLIB_EXTRACT_FLAG_RPFIX |
1538                                                 WIMLIB_EXTRACT_FLAG_NORPFIX))
1539                 return WIMLIB_ERR_INVALID_PARAM;
1540
1541 #ifndef WITH_NTFS_3G
1542         if (extract_flags & WIMLIB_EXTRACT_FLAG_NTFS) {
1543                 ERROR("wimlib was compiled without support for NTFS-3G, so\n"
1544                       "        it cannot apply a WIM image directly to an NTFS volume.");
1545                 return WIMLIB_ERR_UNSUPPORTED;
1546         }
1547 #endif
1548
1549         if (extract_flags & WIMLIB_EXTRACT_FLAG_WIMBOOT) {
1550 #ifdef __WIN32__
1551                 if (!wim->filename)
1552                         return WIMLIB_ERR_NO_FILENAME;
1553 #else
1554                 ERROR("WIMBoot extraction is only supported on Windows!");
1555                 return WIMLIB_ERR_UNSUPPORTED;
1556 #endif
1557         }
1558
1559         if (extract_flags & (WIMLIB_EXTRACT_FLAG_COMPACT_XPRESS4K |
1560                              WIMLIB_EXTRACT_FLAG_COMPACT_XPRESS8K |
1561                              WIMLIB_EXTRACT_FLAG_COMPACT_XPRESS16K |
1562                              WIMLIB_EXTRACT_FLAG_COMPACT_LZX))
1563         {
1564         #ifdef __WIN32__
1565                 int count = 0;
1566                 count += ((extract_flags & WIMLIB_EXTRACT_FLAG_COMPACT_XPRESS4K) != 0);
1567                 count += ((extract_flags & WIMLIB_EXTRACT_FLAG_COMPACT_XPRESS8K) != 0);
1568                 count += ((extract_flags & WIMLIB_EXTRACT_FLAG_COMPACT_XPRESS16K) != 0);
1569                 count += ((extract_flags & WIMLIB_EXTRACT_FLAG_COMPACT_LZX) != 0);
1570                 if (count != 1) {
1571                         ERROR("Only one compression format can be specified "
1572                               "for compact-mode extraction!");
1573                         return WIMLIB_ERR_INVALID_PARAM;
1574                 }
1575                 if (extract_flags & WIMLIB_EXTRACT_FLAG_WIMBOOT) {
1576                         ERROR("Compact-mode extraction and WIMBoot-mode "
1577                               "extraction are mutually exclusive!");
1578                         return WIMLIB_ERR_INVALID_PARAM;
1579                 }
1580         #else
1581                 ERROR("Compact-mode extraction (System Compression) "
1582                       "is only supported on Windows!");
1583                 return WIMLIB_ERR_UNSUPPORTED;
1584         #endif
1585         }
1586
1587
1588         if ((extract_flags & (WIMLIB_EXTRACT_FLAG_RPFIX |
1589                               WIMLIB_EXTRACT_FLAG_NORPFIX |
1590                               WIMLIB_EXTRACT_FLAG_IMAGEMODE)) ==
1591                                         WIMLIB_EXTRACT_FLAG_IMAGEMODE)
1592         {
1593                 /* For full-image extraction, do reparse point fixups by default
1594                  * if the WIM header says they are enabled.  */
1595                 if (wim->hdr.flags & WIM_HDR_FLAG_RP_FIX)
1596                         extract_flags |= WIMLIB_EXTRACT_FLAG_RPFIX;
1597         }
1598
1599         *extract_flags_p = extract_flags;
1600         return 0;
1601 }
1602
1603 struct append_dentry_ctx {
1604         struct wim_dentry **dentries;
1605         size_t num_dentries;
1606         size_t num_alloc_dentries;
1607 };
1608
1609 static int
1610 append_dentry_cb(struct wim_dentry *dentry, void *_ctx)
1611 {
1612         struct append_dentry_ctx *ctx = _ctx;
1613
1614         if (ctx->num_dentries == ctx->num_alloc_dentries) {
1615                 struct wim_dentry **new_dentries;
1616                 size_t new_length;
1617
1618                 new_length = max(ctx->num_alloc_dentries + 8,
1619                                  ctx->num_alloc_dentries * 3 / 2);
1620                 new_dentries = REALLOC(ctx->dentries,
1621                                        new_length * sizeof(ctx->dentries[0]));
1622                 if (new_dentries == NULL)
1623                         return WIMLIB_ERR_NOMEM;
1624                 ctx->dentries = new_dentries;
1625                 ctx->num_alloc_dentries = new_length;
1626         }
1627         ctx->dentries[ctx->num_dentries++] = dentry;
1628         return 0;
1629 }
1630
1631 /* Append dentries matched by a path which can contain wildcard characters.  */
1632 static int
1633 append_matched_dentries(WIMStruct *wim, const tchar *orig_pattern,
1634                         int extract_flags, struct append_dentry_ctx *ctx)
1635 {
1636         const size_t count_before = ctx->num_dentries;
1637         tchar *pattern;
1638         int ret;
1639
1640         pattern = canonicalize_wim_path(orig_pattern);
1641         if (!pattern)
1642                 return WIMLIB_ERR_NOMEM;
1643         ret = expand_path_pattern(wim_get_current_root_dentry(wim), pattern,
1644                                   append_dentry_cb, ctx);
1645         FREE(pattern);
1646         if (ret || ctx->num_dentries > count_before)
1647                 return ret;
1648         if (extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_GLOB) {
1649                 ERROR("No matches for path pattern \"%"TS"\"", orig_pattern);
1650                 return WIMLIB_ERR_PATH_DOES_NOT_EXIST;
1651         }
1652         WARNING("No matches for path pattern \"%"TS"\"", orig_pattern);
1653         return 0;
1654 }
1655
1656 static int
1657 do_wimlib_extract_paths(WIMStruct *wim, int image, const tchar *target,
1658                         const tchar * const *paths, size_t num_paths,
1659                         int extract_flags)
1660 {
1661         int ret;
1662         struct wim_dentry **trees;
1663         size_t num_trees;
1664
1665         if (wim == NULL || target == NULL || target[0] == T('\0') ||
1666             (num_paths != 0 && paths == NULL))
1667                 return WIMLIB_ERR_INVALID_PARAM;
1668
1669         ret = check_extract_flags(wim, &extract_flags);
1670         if (ret)
1671                 return ret;
1672
1673         ret = select_wim_image(wim, image);
1674         if (ret)
1675                 return ret;
1676
1677         ret = wim_checksum_unhashed_blobs(wim);
1678         if (ret)
1679                 return ret;
1680
1681         if ((extract_flags & (WIMLIB_EXTRACT_FLAG_NTFS |
1682                               WIMLIB_EXTRACT_FLAG_NO_PRESERVE_DIR_STRUCTURE)) ==
1683             (WIMLIB_EXTRACT_FLAG_NO_PRESERVE_DIR_STRUCTURE))
1684         {
1685                 ret = mkdir_if_needed(target);
1686                 if (ret)
1687                         return ret;
1688         }
1689
1690         if (extract_flags & WIMLIB_EXTRACT_FLAG_GLOB_PATHS) {
1691
1692                 struct append_dentry_ctx append_dentry_ctx = {
1693                         .dentries = NULL,
1694                         .num_dentries = 0,
1695                         .num_alloc_dentries = 0,
1696                 };
1697
1698                 for (size_t i = 0; i < num_paths; i++) {
1699                         ret = append_matched_dentries(wim, paths[i],
1700                                                       extract_flags,
1701                                                       &append_dentry_ctx);
1702                         if (ret) {
1703                                 trees = append_dentry_ctx.dentries;
1704                                 goto out_free_trees;
1705                         }
1706                 }
1707                 trees = append_dentry_ctx.dentries;
1708                 num_trees = append_dentry_ctx.num_dentries;
1709         } else {
1710                 trees = MALLOC(num_paths * sizeof(trees[0]));
1711                 if (trees == NULL)
1712                         return WIMLIB_ERR_NOMEM;
1713
1714                 for (size_t i = 0; i < num_paths; i++) {
1715
1716                         tchar *path = canonicalize_wim_path(paths[i]);
1717                         if (path == NULL) {
1718                                 ret = WIMLIB_ERR_NOMEM;
1719                                 goto out_free_trees;
1720                         }
1721
1722                         trees[i] = get_dentry(wim, path,
1723                                               WIMLIB_CASE_PLATFORM_DEFAULT);
1724                         FREE(path);
1725                         if (trees[i] == NULL) {
1726                                   ERROR("Path \"%"TS"\" does not exist "
1727                                         "in WIM image %d",
1728                                         paths[i], wim->current_image);
1729                                   ret = WIMLIB_ERR_PATH_DOES_NOT_EXIST;
1730                                   goto out_free_trees;
1731                         }
1732                 }
1733                 num_trees = num_paths;
1734         }
1735
1736         if (num_trees == 0) {
1737                 ret = 0;
1738                 goto out_free_trees;
1739         }
1740
1741         ret = extract_trees(wim, trees, num_trees, target, extract_flags);
1742 out_free_trees:
1743         FREE(trees);
1744         return ret;
1745 }
1746
1747 static int
1748 extract_single_image(WIMStruct *wim, int image,
1749                      const tchar *target, int extract_flags)
1750 {
1751         const tchar *path = WIMLIB_WIM_ROOT_PATH;
1752         extract_flags |= WIMLIB_EXTRACT_FLAG_IMAGEMODE;
1753         return do_wimlib_extract_paths(wim, image, target, &path, 1, extract_flags);
1754 }
1755
1756 static const tchar * const filename_forbidden_chars =
1757 #ifdef __WIN32__
1758 T("<>:\"/\\|?*");
1759 #else
1760 T("/");
1761 #endif
1762
1763 /* This function checks if it is okay to use a WIM image's name as a directory
1764  * name.  */
1765 static bool
1766 image_name_ok_as_dir(const tchar *image_name)
1767 {
1768         return image_name && *image_name &&
1769                 !tstrpbrk(image_name, filename_forbidden_chars) &&
1770                 tstrcmp(image_name, T(".")) &&
1771                 tstrcmp(image_name, T("..")) &&
1772                 tstrlen(image_name) <= 128;
1773 }
1774
1775 /* Extracts all images from the WIM to the directory @target, with the images
1776  * placed in subdirectories named by their image names. */
1777 static int
1778 extract_all_images(WIMStruct *wim, const tchar *target, int extract_flags)
1779 {
1780         size_t output_path_len = tstrlen(target);
1781         tchar buf[output_path_len + 1 + 128 + 1];
1782         int ret;
1783         int image;
1784         const tchar *image_name;
1785
1786         if (extract_flags & WIMLIB_EXTRACT_FLAG_NTFS) {
1787                 ERROR("Cannot extract multiple images in NTFS extraction mode.");
1788                 return WIMLIB_ERR_INVALID_PARAM;
1789         }
1790
1791         ret = mkdir_if_needed(target);
1792         if (ret)
1793                 return ret;
1794         tmemcpy(buf, target, output_path_len);
1795         buf[output_path_len] = OS_PREFERRED_PATH_SEPARATOR;
1796         for (image = 1; image <= wim->hdr.image_count; image++) {
1797                 image_name = wimlib_get_image_name(wim, image);
1798                 if (image_name_ok_as_dir(image_name)) {
1799                         tstrcpy(buf + output_path_len + 1, image_name);
1800                 } else {
1801                         /* Image name is empty or contains forbidden characters.
1802                          * Use image number instead. */
1803                         tsprintf(buf + output_path_len + 1, T("%d"), image);
1804                 }
1805                 ret = extract_single_image(wim, image, buf, extract_flags);
1806                 if (ret)
1807                         return ret;
1808         }
1809         return 0;
1810 }
1811
1812 static int
1813 do_wimlib_extract_image(WIMStruct *wim, int image, const tchar *target,
1814                         int extract_flags)
1815 {
1816         if (extract_flags & (WIMLIB_EXTRACT_FLAG_NO_PRESERVE_DIR_STRUCTURE |
1817                              WIMLIB_EXTRACT_FLAG_TO_STDOUT |
1818                              WIMLIB_EXTRACT_FLAG_GLOB_PATHS))
1819                 return WIMLIB_ERR_INVALID_PARAM;
1820
1821         if (image == WIMLIB_ALL_IMAGES)
1822                 return extract_all_images(wim, target, extract_flags);
1823         else
1824                 return extract_single_image(wim, image, target, extract_flags);
1825 }
1826
1827
1828 /****************************************************************************
1829  *                          Extraction API                                  *
1830  ****************************************************************************/
1831
1832 WIMLIBAPI int
1833 wimlib_extract_paths(WIMStruct *wim, int image, const tchar *target,
1834                      const tchar * const *paths, size_t num_paths,
1835                      int extract_flags)
1836 {
1837         if (extract_flags & ~WIMLIB_EXTRACT_MASK_PUBLIC)
1838                 return WIMLIB_ERR_INVALID_PARAM;
1839
1840         return do_wimlib_extract_paths(wim, image, target, paths, num_paths,
1841                                        extract_flags);
1842 }
1843
1844 WIMLIBAPI int
1845 wimlib_extract_pathlist(WIMStruct *wim, int image, const tchar *target,
1846                         const tchar *path_list_file, int extract_flags)
1847 {
1848         int ret;
1849         tchar **paths;
1850         size_t num_paths;
1851         void *mem;
1852
1853         ret = read_path_list_file(path_list_file, &paths, &num_paths, &mem);
1854         if (ret) {
1855                 ERROR("Failed to read path list file \"%"TS"\"",
1856                       path_list_file);
1857                 return ret;
1858         }
1859
1860         ret = wimlib_extract_paths(wim, image, target,
1861                                    (const tchar * const *)paths, num_paths,
1862                                    extract_flags);
1863         FREE(paths);
1864         FREE(mem);
1865         return ret;
1866 }
1867
1868 WIMLIBAPI int
1869 wimlib_extract_image_from_pipe_with_progress(int pipe_fd,
1870                                              const tchar *image_num_or_name,
1871                                              const tchar *target,
1872                                              int extract_flags,
1873                                              wimlib_progress_func_t progfunc,
1874                                              void *progctx)
1875 {
1876         int ret;
1877         WIMStruct *pwm;
1878         struct filedes *in_fd;
1879         int image;
1880         unsigned i;
1881
1882         if (extract_flags & ~WIMLIB_EXTRACT_MASK_PUBLIC)
1883                 return WIMLIB_ERR_INVALID_PARAM;
1884
1885         /* Read the WIM header from the pipe and get a WIMStruct to represent
1886          * the pipable WIM.  Caveats:  Unlike getting a WIMStruct with
1887          * wimlib_open_wim(), getting a WIMStruct in this way will result in an
1888          * empty blob table, no XML data read, and no filename set.  */
1889         ret = open_wim_as_WIMStruct(&pipe_fd, WIMLIB_OPEN_FLAG_FROM_PIPE, &pwm,
1890                                     progfunc, progctx);
1891         if (ret)
1892                 return ret;
1893
1894         /* Sanity check to make sure this is a pipable WIM.  */
1895         if (pwm->hdr.magic != PWM_MAGIC) {
1896                 ERROR("The WIM being read from file descriptor %d "
1897                       "is not pipable!", pipe_fd);
1898                 ret = WIMLIB_ERR_NOT_PIPABLE;
1899                 goto out_wimlib_free;
1900         }
1901
1902         /* Sanity check to make sure the first part of a pipable split WIM is
1903          * sent over the pipe first.  */
1904         if (pwm->hdr.part_number != 1) {
1905                 ERROR("The first part of the split WIM must be "
1906                       "sent over the pipe first.");
1907                 ret = WIMLIB_ERR_INVALID_PIPABLE_WIM;
1908                 goto out_wimlib_free;
1909         }
1910
1911         in_fd = &pwm->in_fd;
1912         wimlib_assert(in_fd->offset == WIM_HEADER_DISK_SIZE);
1913
1914         /* As mentioned, the WIMStruct we created from the pipe does not have
1915          * XML data yet.  Fix this by reading the extra copy of the XML data
1916          * that directly follows the header in pipable WIMs.  (Note: see
1917          * write_pipable_wim() for more details about the format of pipable
1918          * WIMs.)  */
1919         {
1920                 u8 hash[SHA1_HASH_SIZE];
1921
1922                 ret = read_pwm_blob_header(pwm, hash,
1923                                            &pwm->hdr.xml_data_reshdr, NULL);
1924                 if (ret)
1925                         goto out_wimlib_free;
1926
1927                 if (!(pwm->hdr.xml_data_reshdr.flags & WIM_RESHDR_FLAG_METADATA)) {
1928                         ERROR("Expected XML data, but found non-metadata resource.");
1929                         ret = WIMLIB_ERR_INVALID_PIPABLE_WIM;
1930                         goto out_wimlib_free;
1931                 }
1932
1933                 ret = read_wim_xml_data(pwm);
1934                 if (ret)
1935                         goto out_wimlib_free;
1936
1937                 if (xml_get_image_count(pwm->xml_info) != pwm->hdr.image_count) {
1938                         ERROR("Image count in XML data is not the same as in WIM header.");
1939                         ret = WIMLIB_ERR_IMAGE_COUNT;
1940                         goto out_wimlib_free;
1941                 }
1942         }
1943
1944         /* Get image index (this may use the XML data that was just read to
1945          * resolve an image name).  */
1946         if (image_num_or_name) {
1947                 image = wimlib_resolve_image(pwm, image_num_or_name);
1948                 if (image == WIMLIB_NO_IMAGE) {
1949                         ERROR("\"%"TS"\" is not a valid image in the pipable WIM!",
1950                               image_num_or_name);
1951                         ret = WIMLIB_ERR_INVALID_IMAGE;
1952                         goto out_wimlib_free;
1953                 } else if (image == WIMLIB_ALL_IMAGES) {
1954                         ERROR("Applying all images from a pipe is not supported!");
1955                         ret = WIMLIB_ERR_INVALID_IMAGE;
1956                         goto out_wimlib_free;
1957                 }
1958         } else {
1959                 if (pwm->hdr.image_count != 1) {
1960                         ERROR("No image was specified, but the pipable WIM "
1961                               "did not contain exactly 1 image");
1962                         ret = WIMLIB_ERR_INVALID_IMAGE;
1963                         goto out_wimlib_free;
1964                 }
1965                 image = 1;
1966         }
1967
1968         /* Load the needed metadata resource.  */
1969         for (i = 1; i <= pwm->hdr.image_count; i++) {
1970                 ret = handle_pwm_metadata_resource(pwm, i, i == image);
1971                 if (ret)
1972                         goto out_wimlib_free;
1973         }
1974         /* Extract the image.  */
1975         extract_flags |= WIMLIB_EXTRACT_FLAG_FROM_PIPE;
1976         ret = do_wimlib_extract_image(pwm, image, target, extract_flags);
1977         /* Clean up and return.  */
1978 out_wimlib_free:
1979         wimlib_free(pwm);
1980         return ret;
1981 }
1982
1983
1984 WIMLIBAPI int
1985 wimlib_extract_image_from_pipe(int pipe_fd, const tchar *image_num_or_name,
1986                                const tchar *target, int extract_flags)
1987 {
1988         return wimlib_extract_image_from_pipe_with_progress(pipe_fd,
1989                                                             image_num_or_name,
1990                                                             target,
1991                                                             extract_flags,
1992                                                             NULL,
1993                                                             NULL);
1994 }
1995
1996 WIMLIBAPI int
1997 wimlib_extract_image(WIMStruct *wim, int image, const tchar *target,
1998                      int extract_flags)
1999 {
2000         if (extract_flags & ~WIMLIB_EXTRACT_MASK_PUBLIC)
2001                 return WIMLIB_ERR_INVALID_PARAM;
2002         return do_wimlib_extract_image(wim, image, target, extract_flags);
2003 }