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, 2013, 2014, 2015 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 <sys/stat.h>
  45 #include <unistd.h>
  46
  47 #include "wimlib/apply.h"
  48 #include "wimlib/assert.h"
  49 #include "wimlib/blob_table.h"
  50 #include "wimlib/dentry.h"
  51 #include "wimlib/encoding.h"
  52 #include "wimlib/endianness.h"
  53 #include "wimlib/error.h"
  54 #include "wimlib/metadata.h"
  55 #include "wimlib/pathlist.h"
  56 #include "wimlib/paths.h"
  57 #include "wimlib/reparse.h"
  58 #include "wimlib/resource.h"
  59 #include "wimlib/security.h"
  60 #include "wimlib/unix_data.h"
  61 #include "wimlib/wildcard.h"
  62 #include "wimlib/wim.h"
  63 #include "wimlib/win32.h" /* for realpath() equivalent */
  64 #include "wimlib/xml.h"
  65
  66 #define WIMLIB_EXTRACT_FLAG_FROM_PIPE   0x80000000
  67 #define WIMLIB_EXTRACT_FLAG_IMAGEMODE   0x40000000
  68
  69 /* Keep in sync with wimlib.h  */
  70 #define WIMLIB_EXTRACT_MASK_PUBLIC                              \
  71         (WIMLIB_EXTRACT_FLAG_NTFS                       |       \
  72          WIMLIB_EXTRACT_FLAG_UNIX_DATA                  |       \
  73          WIMLIB_EXTRACT_FLAG_NO_ACLS                    |       \
  74          WIMLIB_EXTRACT_FLAG_STRICT_ACLS                |       \
  75          WIMLIB_EXTRACT_FLAG_RPFIX                      |       \
  76          WIMLIB_EXTRACT_FLAG_NORPFIX                    |       \
  77          WIMLIB_EXTRACT_FLAG_TO_STDOUT                  |       \
  78          WIMLIB_EXTRACT_FLAG_REPLACE_INVALID_FILENAMES  |       \
  79          WIMLIB_EXTRACT_FLAG_ALL_CASE_CONFLICTS         |       \
  80          WIMLIB_EXTRACT_FLAG_STRICT_TIMESTAMPS          |       \
  81          WIMLIB_EXTRACT_FLAG_STRICT_SHORT_NAMES         |       \
  82          WIMLIB_EXTRACT_FLAG_STRICT_SYMLINKS            |       \
  83          WIMLIB_EXTRACT_FLAG_GLOB_PATHS                 |       \
  84          WIMLIB_EXTRACT_FLAG_STRICT_GLOB                |       \
  85          WIMLIB_EXTRACT_FLAG_NO_ATTRIBUTES              |       \
  86          WIMLIB_EXTRACT_FLAG_NO_PRESERVE_DIR_STRUCTURE  |       \
  87          WIMLIB_EXTRACT_FLAG_WIMBOOT)
  88
  89 /* Send WIMLIB_PROGRESS_MSG_EXTRACT_FILE_STRUCTURE or
  90  * WIMLIB_PROGRESS_MSG_EXTRACT_METADATA.  */
  91 int
  92 do_file_extract_progress(struct apply_ctx *ctx, enum wimlib_progress_msg msg)
  93 {
  94         ctx->count_until_file_progress = 500;  /* Arbitrary value to limit calls  */
  95         return extract_progress(ctx, msg);
  96 }
  97
  98 static int
  99 start_file_phase(struct apply_ctx *ctx, u64 end_file_count, enum wimlib_progress_msg msg)
 100 {
 101         ctx->progress.extract.current_file_count = 0;
 102         ctx->progress.extract.end_file_count = end_file_count;
 103         return do_file_extract_progress(ctx, msg);
 104 }
 105
 106 int
 107 start_file_structure_phase(struct apply_ctx *ctx, u64 end_file_count)
 108 {
 109         return start_file_phase(ctx, end_file_count, WIMLIB_PROGRESS_MSG_EXTRACT_FILE_STRUCTURE);
 110 }
 111
 112 int
 113 start_file_metadata_phase(struct apply_ctx *ctx, u64 end_file_count)
 114 {
 115         return start_file_phase(ctx, end_file_count, WIMLIB_PROGRESS_MSG_EXTRACT_METADATA);
 116 }
 117
 118 static int
 119 end_file_phase(struct apply_ctx *ctx, enum wimlib_progress_msg msg)
 120 {
 121         ctx->progress.extract.current_file_count = ctx->progress.extract.end_file_count;
 122         return do_file_extract_progress(ctx, msg);
 123 }
 124
 125 int
 126 end_file_structure_phase(struct apply_ctx *ctx)
 127 {
 128         return end_file_phase(ctx, WIMLIB_PROGRESS_MSG_EXTRACT_FILE_STRUCTURE);
 129 }
 130
 131 int
 132 end_file_metadata_phase(struct apply_ctx *ctx)
 133 {
 134         return end_file_phase(ctx, WIMLIB_PROGRESS_MSG_EXTRACT_METADATA);
 135 }
 136
 137 #define PWM_ALLOW_WIM_HDR 0x00001
 138
 139 /* Read the header for a blob in a pipable WIM.  */
 140 static int
 141 read_pwm_blob_header(WIMStruct *pwm, struct blob_descriptor *blob,
 142                      struct wim_resource_descriptor *rdesc,
 143                      int flags, struct wim_header_disk *hdr_ret)
 144 {
 145         union {
 146                 struct pwm_blob_hdr blob_hdr;
 147                 struct wim_header_disk pwm_hdr;
 148         } buf;
 149         struct wim_reshdr reshdr;
 150         int ret;
 151
 152         ret = full_read(&pwm->in_fd, &buf.blob_hdr, sizeof(buf.blob_hdr));
 153         if (ret)
 154                 goto read_error;
 155
 156         if ((flags & PWM_ALLOW_WIM_HDR) &&
 157             le64_to_cpu(buf.blob_hdr.magic) == PWM_MAGIC)
 158         {
 159                 BUILD_BUG_ON(sizeof(buf.pwm_hdr) < sizeof(buf.blob_hdr));
 160                 ret = full_read(&pwm->in_fd, &buf.blob_hdr + 1,
 161                                 sizeof(buf.pwm_hdr) - sizeof(buf.blob_hdr));
 162
 163                 if (ret)
 164                         goto read_error;
 165                 blob->blob_location = BLOB_NONEXISTENT;
 166                 memcpy(hdr_ret, &buf.pwm_hdr, sizeof(buf.pwm_hdr));
 167                 return 0;
 168         }
 169
 170         if (le64_to_cpu(buf.blob_hdr.magic) != PWM_BLOB_MAGIC) {
 171                 ERROR("Data read on pipe is invalid (expected blob header).");
 172                 return WIMLIB_ERR_INVALID_PIPABLE_WIM;
 173         }
 174
 175         copy_hash(blob->hash, buf.blob_hdr.hash);
 176
 177         reshdr.size_in_wim = 0;
 178         reshdr.flags = le32_to_cpu(buf.blob_hdr.flags);
 179         reshdr.offset_in_wim = pwm->in_fd.offset;
 180         reshdr.uncompressed_size = le64_to_cpu(buf.blob_hdr.uncompressed_size);
 181         wim_res_hdr_to_desc(&reshdr, pwm, rdesc);
 182         blob_set_is_located_in_nonsolid_wim_resource(blob, rdesc);
 183         blob->is_metadata = (rdesc->flags & WIM_RESHDR_FLAG_METADATA) != 0;
 184         return 0;
 185
 186 read_error:
 187         ERROR_WITH_ERRNO("Error reading pipable WIM from pipe");
 188         return ret;
 189 }
 190
 191 static int
 192 read_blobs_from_pipe(struct apply_ctx *ctx,
 193                      const struct read_blob_list_callbacks *cbs)
 194 {
 195         struct blob_descriptor *found_blob = NULL;
 196         struct wim_resource_descriptor *rdesc = NULL;
 197         struct blob_table *blob_table;
 198         int ret;
 199
 200         ret = WIMLIB_ERR_NOMEM;
 201         found_blob = new_blob_descriptor();
 202         if (!found_blob)
 203                 goto out;
 204
 205         rdesc = MALLOC(sizeof(struct wim_resource_descriptor));
 206         if (!rdesc)
 207                 goto out;
 208
 209         blob_table = ctx->wim->blob_table;
 210         memcpy(ctx->progress.extract.guid, ctx->wim->hdr.guid, WIM_GUID_LEN);
 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                 goto out;
 216
 217         while (ctx->num_blobs_remaining) {
 218                 struct wim_header_disk pwm_hdr;
 219                 struct blob_descriptor *needed_blob;
 220
 221                 if (found_blob->blob_location != BLOB_NONEXISTENT)
 222                         blob_unset_is_located_in_wim_resource(found_blob);
 223                 ret = read_pwm_blob_header(ctx->wim, found_blob, rdesc,
 224                                            PWM_ALLOW_WIM_HDR, &pwm_hdr);
 225                 if (ret)
 226                         goto out;
 227
 228                 if ((found_blob->blob_location != BLOB_NONEXISTENT)
 229                     && !found_blob->is_metadata
 230                     && (needed_blob = lookup_blob(blob_table, found_blob->hash))
 231                     && (needed_blob->out_refcnt))
 232                 {
 233                         blob_unset_is_located_in_wim_resource(found_blob);
 234                         blob_set_is_located_in_nonsolid_wim_resource(needed_blob, rdesc);
 235
 236                         ret = (*cbs->begin_blob)(needed_blob,
 237                                                  cbs->begin_blob_ctx);
 238                         if (ret) {
 239                                 blob_unset_is_located_in_wim_resource(needed_blob);
 240                                 goto out;
 241                         }
 242
 243                         ret = extract_blob(needed_blob, needed_blob->size,
 244                                            cbs->consume_chunk,
 245                                            cbs->consume_chunk_ctx);
 246
 247                         ret = (*cbs->end_blob)(needed_blob, ret,
 248                                                cbs->end_blob_ctx);
 249                         blob_unset_is_located_in_wim_resource(needed_blob);
 250                         if (ret)
 251                                 goto out;
 252                         ctx->num_blobs_remaining--;
 253                 } else if (found_blob->blob_location != BLOB_NONEXISTENT) {
 254                         ret = skip_wim_resource(found_blob->rdesc);
 255                         if (ret)
 256                                 goto out;
 257                 } else {
 258                         u16 part_number = le16_to_cpu(pwm_hdr.part_number);
 259                         u16 total_parts = le16_to_cpu(pwm_hdr.total_parts);
 260
 261                         if (part_number != ctx->progress.extract.part_number ||
 262                             total_parts != ctx->progress.extract.total_parts ||
 263                             memcmp(pwm_hdr.guid, ctx->progress.extract.guid,
 264                                    WIM_GUID_LEN))
 265                         {
 266                                 ctx->progress.extract.part_number = part_number;
 267                                 ctx->progress.extract.total_parts = total_parts;
 268                                 memcpy(ctx->progress.extract.guid,
 269                                        pwm_hdr.guid, WIM_GUID_LEN);
 270                                 ret = extract_progress(ctx,
 271                                                        WIMLIB_PROGRESS_MSG_EXTRACT_SPWM_PART_BEGIN);
 272                                 if (ret)
 273                                         goto out;
 274                         }
 275                 }
 276         }
 277         ret = 0;
 278 out:
 279         if (found_blob && found_blob->blob_location != BLOB_IN_WIM)
 280                 FREE(rdesc);
 281         free_blob_descriptor(found_blob);
 282         return ret;
 283 }
 284
 285 /* Creates a temporary file opened for writing.  The open file descriptor is
 286  * returned in @fd_ret and its name is returned in @name_ret (dynamically
 287  * allocated).  */
 288 static int
 289 create_temporary_file(struct filedes *fd_ret, tchar **name_ret)
 290 {
 291         tchar *name;
 292         int open_flags;
 293         int raw_fd;
 294
 295 retry:
 296         name = ttempnam(NULL, T("wimlib"));
 297         if (!name) {
 298                 ERROR_WITH_ERRNO("Failed to create temporary filename");
 299                 return WIMLIB_ERR_NOMEM;
 300         }
 301
 302         open_flags = O_WRONLY | O_CREAT | O_EXCL | O_BINARY;
 303 #ifdef __WIN32__
 304         open_flags |= _O_SHORT_LIVED;
 305 #endif
 306         raw_fd = topen(name, open_flags, 0600);
 307
 308         if (raw_fd < 0) {
 309                 if (errno == EEXIST) {
 310                         FREE(name);
 311                         goto retry;
 312                 }
 313                 ERROR_WITH_ERRNO("Failed to create temporary file "
 314                                  "\"%"TS"\"", name);
 315                 FREE(name);
 316                 return WIMLIB_ERR_OPEN;
 317         }
 318
 319         filedes_init(fd_ret, raw_fd);
 320         *name_ret = name;
 321         return 0;
 322 }
 323
 324 static int
 325 begin_extract_blob_wrapper(struct blob_descriptor *blob, void *_ctx)
 326 {
 327         struct apply_ctx *ctx = _ctx;
 328
 329         ctx->cur_blob = blob;
 330         ctx->cur_blob_offset = 0;
 331
 332         if (unlikely(blob->out_refcnt > MAX_OPEN_FILES))
 333                 return create_temporary_file(&ctx->tmpfile_fd, &ctx->tmpfile_name);
 334         else
 335                 return (*ctx->saved_cbs->begin_blob)(blob, ctx->saved_cbs->begin_blob_ctx);
 336 }
 337
 338 static int
 339 extract_chunk_wrapper(const void *chunk, size_t size, void *_ctx)
 340 {
 341         struct apply_ctx *ctx = _ctx;
 342         union wimlib_progress_info *progress = &ctx->progress;
 343         int ret;
 344
 345         ctx->cur_blob_offset += size;
 346
 347         if (likely(ctx->supported_features.hard_links)) {
 348                 progress->extract.completed_bytes +=
 349                         (u64)size * ctx->cur_blob->out_refcnt;
 350                 if (ctx->cur_blob_offset == ctx->cur_blob->size)
 351                         progress->extract.completed_streams += ctx->cur_blob->out_refcnt;
 352         } else {
 353                 const struct blob_extraction_target *targets =
 354                         blob_extraction_targets(ctx->cur_blob);
 355                 for (u32 i = 0; i < ctx->cur_blob->out_refcnt; i++) {
 356                         const struct wim_inode *inode = targets[i].inode;
 357                         const struct wim_dentry *dentry;
 358
 359                         list_for_each_entry(dentry,
 360                                             &inode->i_extraction_aliases,
 361                                             d_extraction_alias_node)
 362                         {
 363                                 progress->extract.completed_bytes += size;
 364                                 if (ctx->cur_blob_offset == ctx->cur_blob->size)
 365                                         progress->extract.completed_streams++;
 366                         }
 367                 }
 368         }
 369         if (progress->extract.completed_bytes >= ctx->next_progress) {
 370
 371                 ret = extract_progress(ctx, WIMLIB_PROGRESS_MSG_EXTRACT_STREAMS);
 372                 if (ret)
 373                         return ret;
 374
 375                 if (progress->extract.completed_bytes >=
 376                     progress->extract.total_bytes)
 377                 {
 378                         ctx->next_progress = UINT64_MAX;
 379                 } else {
 380                         /* Send new message as soon as another 1/128 of the
 381                          * total has been extracted.  (Arbitrary number.)  */
 382                         ctx->next_progress =
 383                                 progress->extract.completed_bytes +
 384                                         progress->extract.total_bytes / 128;
 385
 386                         /* ... Unless that would be more than 5000000 bytes, in
 387                          * which case send the next after the next 5000000
 388                          * bytes.  (Another arbitrary number.)  */
 389                         if (progress->extract.completed_bytes + 5000000 <
 390                             ctx->next_progress)
 391                                 ctx->next_progress =
 392                                         progress->extract.completed_bytes + 5000000;
 393
 394                         /* ... But always send a message as soon as we're
 395                          * completely done.  */
 396                         if (progress->extract.total_bytes < ctx->next_progress)
 397                                 ctx->next_progress = progress->extract.total_bytes;
 398                 }
 399         }
 400
 401         if (unlikely(filedes_valid(&ctx->tmpfile_fd))) {
 402                 /* Just extracting to temporary file for now.  */
 403                 ret = full_write(&ctx->tmpfile_fd, chunk, size);
 404                 if (ret) {
 405                         ERROR_WITH_ERRNO("Error writing data to "
 406                                          "temporary file \"%"TS"\"",
 407                                          ctx->tmpfile_name);
 408                 }
 409                 return ret;
 410         } else {
 411                 return (*ctx->saved_cbs->consume_chunk)(chunk, size,
 412                                                         ctx->saved_cbs->consume_chunk_ctx);
 413         }
 414 }
 415
 416 static int
 417 extract_from_tmpfile(const tchar *tmpfile_name, struct apply_ctx *ctx)
 418 {
 419         struct blob_descriptor tmpfile_blob;
 420         struct blob_descriptor *orig_blob = ctx->cur_blob;
 421         const struct read_blob_list_callbacks *cbs = ctx->saved_cbs;
 422         int ret;
 423         const u32 orig_refcnt = orig_blob->out_refcnt;
 424
 425         BUILD_BUG_ON(MAX_OPEN_FILES <
 426                      ARRAY_LEN(orig_blob->inline_blob_extraction_targets));
 427
 428         struct blob_extraction_target *targets = orig_blob->blob_extraction_targets;
 429
 430         /* Copy the blob's data from the temporary file to each of its targets.
 431          *
 432          * This is executed only in the very uncommon case that a blob is being
 433          * extracted to more than MAX_OPEN_FILES targets!  */
 434
 435         memcpy(&tmpfile_blob, orig_blob, sizeof(struct blob_descriptor));
 436         tmpfile_blob.blob_location = BLOB_IN_FILE_ON_DISK;
 437         tmpfile_blob.file_on_disk = ctx->tmpfile_name;
 438         ret = 0;
 439         for (u32 i = 0; i < orig_refcnt; i++) {
 440
 441                 /* Note: it usually doesn't matter whether we pass the original
 442                  * blob descriptor to callbacks provided by the extraction
 443                  * backend as opposed to the tmpfile blob descriptor, since they
 444                  * shouldn't actually read data from the blob other than through
 445                  * the read_blob_prefix() call below.  But for
 446                  * WIMLIB_EXTRACT_FLAG_WIMBOOT mode on Windows it does matter
 447                  * because it needs access to the original WIM resource
 448                  * descriptor in order to create the external backing reference.
 449                  */
 450
 451                 orig_blob->out_refcnt = 1;
 452                 orig_blob->inline_blob_extraction_targets[0] = targets[i];
 453
 454                 ret = (*cbs->begin_blob)(orig_blob, cbs->begin_blob_ctx);
 455                 if (ret)
 456                         break;
 457
 458                 /* Extra SHA-1 isn't necessary here, but it shouldn't hurt as
 459                  * this case is very rare anyway.  */
 460                 ret = extract_blob(&tmpfile_blob, tmpfile_blob.size,
 461                                    cbs->consume_chunk,
 462                                    cbs->consume_chunk_ctx);
 463
 464                 ret = (*cbs->end_blob)(orig_blob, ret, cbs->end_blob_ctx);
 465                 if (ret)
 466                         break;
 467         }
 468         FREE(targets);
 469         orig_blob->out_refcnt = 0;
 470         return ret;
 471 }
 472
 473 static int
 474 end_extract_blob_wrapper(struct blob_descriptor *blob, int status, void *_ctx)
 475 {
 476         struct apply_ctx *ctx = _ctx;
 477
 478         if (unlikely(filedes_valid(&ctx->tmpfile_fd))) {
 479                 filedes_close(&ctx->tmpfile_fd);
 480                 if (!status)
 481                         status = extract_from_tmpfile(ctx->tmpfile_name, ctx);
 482                 filedes_invalidate(&ctx->tmpfile_fd);
 483                 tunlink(ctx->tmpfile_name);
 484                 FREE(ctx->tmpfile_name);
 485                 return status;
 486         } else {
 487                 return (*ctx->saved_cbs->end_blob)(blob, status,
 488                                                    ctx->saved_cbs->end_blob_ctx);
 489         }
 490 }
 491
 492 /*
 493  * Read the list of blobs to extract and feed their data into the specified
 494  * callback functions.
 495  *
 496  * This handles checksumming each blob.
 497  *
 498  * This also handles sending WIMLIB_PROGRESS_MSG_EXTRACT_STREAMS.
 499  *
 500  * This also works if the WIM is being read from a pipe, whereas attempting to
 501  * read blobs directly (e.g. with read_full_blob_into_buf()) will not.
 502  *
 503  * This also will split up blobs that will need to be extracted to more than
 504  * MAX_OPEN_FILES locations, as measured by the 'out_refcnt' of each blob.
 505  * Therefore, the apply_operations implementation need not worry about running
 506  * out of file descriptors, unless it might open more than one file descriptor
 507  * per 'blob_extraction_target' (e.g. Win32 currently might because the
 508  * destination file system might not support hard links).
 509  */
 510 int
 511 extract_blob_list(struct apply_ctx *ctx,
 512                   const struct read_blob_list_callbacks *cbs)
 513 {
 514         struct read_blob_list_callbacks wrapper_cbs = {
 515                 .begin_blob        = begin_extract_blob_wrapper,
 516                 .begin_blob_ctx    = ctx,
 517                 .consume_chunk     = extract_chunk_wrapper,
 518                 .consume_chunk_ctx = ctx,
 519                 .end_blob          = end_extract_blob_wrapper,
 520                 .end_blob_ctx      = ctx,
 521         };
 522         ctx->saved_cbs = cbs;
 523         if (ctx->extract_flags & WIMLIB_EXTRACT_FLAG_FROM_PIPE) {
 524                 return read_blobs_from_pipe(ctx, &wrapper_cbs);
 525         } else {
 526                 return read_blob_list(&ctx->blob_list,
 527                                       offsetof(struct blob_descriptor,
 528                                                extraction_list),
 529                                       &wrapper_cbs, VERIFY_BLOB_HASHES);
 530         }
 531 }
 532
 533 /* Extract a WIM dentry to standard output.
 534  *
 535  * This obviously doesn't make sense in all cases.  We return an error if the
 536  * dentry does not correspond to a regular file.  Otherwise we extract the
 537  * unnamed data stream only.  */
 538 static int
 539 extract_dentry_to_stdout(struct wim_dentry *dentry,
 540                          const struct blob_table *blob_table)
 541 {
 542         struct wim_inode *inode = dentry->d_inode;
 543         struct blob_descriptor *blob;
 544         struct filedes _stdout;
 545
 546         if (inode->i_attributes & (FILE_ATTRIBUTE_REPARSE_POINT |
 547                                    FILE_ATTRIBUTE_DIRECTORY |
 548                                    FILE_ATTRIBUTE_ENCRYPTED))
 549         {
 550                 ERROR("\"%"TS"\" is not a regular file and therefore cannot be "
 551                       "extracted to standard output", dentry_full_path(dentry));
 552                 return WIMLIB_ERR_NOT_A_REGULAR_FILE;
 553         }
 554
 555         blob = inode_get_blob_for_unnamed_data_stream(inode, blob_table);
 556         if (!blob) {
 557                 const u8 *hash = inode_get_hash_of_unnamed_data_stream(inode);
 558                 if (!is_zero_hash(hash))
 559                         return blob_not_found_error(inode, hash);
 560                 return 0;
 561         }
 562
 563         filedes_init(&_stdout, STDOUT_FILENO);
 564         return extract_full_blob_to_fd(blob, &_stdout);
 565 }
 566
 567 static int
 568 extract_dentries_to_stdout(struct wim_dentry **dentries, size_t num_dentries,
 569                            const struct blob_table *blob_table)
 570 {
 571         for (size_t i = 0; i < num_dentries; i++) {
 572                 int ret = extract_dentry_to_stdout(dentries[i], blob_table);
 573                 if (ret)
 574                         return ret;
 575         }
 576         return 0;
 577 }
 578
 579 /**********************************************************************/
 580
 581 /*
 582  * Removes duplicate dentries from the array.
 583  *
 584  * Returns the new number of dentries, packed at the front of the array.
 585  */
 586 static size_t
 587 remove_duplicate_trees(struct wim_dentry **trees, size_t num_trees)
 588 {
 589         size_t i, j = 0;
 590         for (i = 0; i < num_trees; i++) {
 591                 if (!trees[i]->tmp_flag) {
 592                         /* Found distinct dentry.  */
 593                         trees[i]->tmp_flag = 1;
 594                         trees[j++] = trees[i];
 595                 }
 596         }
 597         for (i = 0; i < j; i++)
 598                 trees[i]->tmp_flag = 0;
 599         return j;
 600 }
 601
 602 /*
 603  * Remove dentries that are descendants of other dentries in the array.
 604  *
 605  * Returns the new number of dentries, packed at the front of the array.
 606  */
 607 static size_t
 608 remove_contained_trees(struct wim_dentry **trees, size_t num_trees)
 609 {
 610         size_t i, j = 0;
 611         for (i = 0; i < num_trees; i++)
 612                 trees[i]->tmp_flag = 1;
 613         for (i = 0; i < num_trees; i++) {
 614                 struct wim_dentry *d = trees[i];
 615                 while (!dentry_is_root(d)) {
 616                         d = d->d_parent;
 617                         if (d->tmp_flag)
 618                                 goto tree_contained;
 619                 }
 620                 trees[j++] = trees[i];
 621                 continue;
 622
 623         tree_contained:
 624                 trees[i]->tmp_flag = 0;
 625         }
 626
 627         for (i = 0; i < j; i++)
 628                 trees[i]->tmp_flag = 0;
 629         return j;
 630 }
 631
 632 static int
 633 dentry_append_to_list(struct wim_dentry *dentry, void *_dentry_list)
 634 {
 635         struct list_head *dentry_list = _dentry_list;
 636         list_add_tail(&dentry->d_extraction_list_node, dentry_list);
 637         return 0;
 638 }
 639
 640 static void
 641 dentry_reset_extraction_list_node(struct wim_dentry *dentry)
 642 {
 643         dentry->d_extraction_list_node = (struct list_head){NULL, NULL};
 644 }
 645
 646 static int
 647 dentry_delete_from_list(struct wim_dentry *dentry, void *_ignore)
 648 {
 649         list_del(&dentry->d_extraction_list_node);
 650         dentry_reset_extraction_list_node(dentry);
 651         return 0;
 652 }
 653
 654 /*
 655  * Build the preliminary list of dentries to be extracted.
 656  *
 657  * The list maintains the invariant that if d1 and d2 are in the list and d1 is
 658  * an ancestor of d2, then d1 appears before d2 in the list.
 659  */
 660 static void
 661 build_dentry_list(struct list_head *dentry_list, struct wim_dentry **trees,
 662                   size_t num_trees, bool add_ancestors)
 663 {
 664         INIT_LIST_HEAD(dentry_list);
 665
 666         /* Add the trees recursively.  */
 667         for (size_t i = 0; i < num_trees; i++)
 668                 for_dentry_in_tree(trees[i], dentry_append_to_list, dentry_list);
 669
 670         /* If requested, add ancestors of the trees.  */
 671         if (add_ancestors) {
 672                 for (size_t i = 0; i < num_trees; i++) {
 673                         struct wim_dentry *dentry = trees[i];
 674                         struct wim_dentry *ancestor;
 675                         struct list_head *place_after;
 676
 677                         if (dentry_is_root(dentry))
 678                                 continue;
 679
 680                         place_after = dentry_list;
 681                         ancestor = dentry;
 682                         do {
 683                                 ancestor = ancestor->d_parent;
 684                                 if (will_extract_dentry(ancestor)) {
 685                                         place_after = &ancestor->d_extraction_list_node;
 686                                         break;
 687                                 }
 688                         } while (!dentry_is_root(ancestor));
 689
 690                         ancestor = dentry;
 691                         do {
 692                                 ancestor = ancestor->d_parent;
 693                                 if (will_extract_dentry(ancestor))
 694                                         break;
 695                                 list_add(&ancestor->d_extraction_list_node, place_after);
 696                         } while (!dentry_is_root(ancestor));
 697                 }
 698         }
 699 }
 700
 701 static void
 702 destroy_dentry_list(struct list_head *dentry_list)
 703 {
 704         struct wim_dentry *dentry, *tmp;
 705         struct wim_inode *inode;
 706
 707         list_for_each_entry_safe(dentry, tmp, dentry_list, d_extraction_list_node) {
 708                 inode = dentry->d_inode;
 709                 dentry_reset_extraction_list_node(dentry);
 710                 inode->i_visited = 0;
 711                 inode->i_can_externally_back = 0;
 712                 if ((void *)dentry->d_extraction_name != (void *)dentry->file_name)
 713                         FREE(dentry->d_extraction_name);
 714                 dentry->d_extraction_name = NULL;
 715                 dentry->d_extraction_name_nchars = 0;
 716         }
 717 }
 718
 719 static void
 720 destroy_blob_list(struct list_head *blob_list)
 721 {
 722         struct blob_descriptor *blob;
 723
 724         list_for_each_entry(blob, blob_list, extraction_list)
 725                 if (blob->out_refcnt > ARRAY_LEN(blob->inline_blob_extraction_targets))
 726                         FREE(blob->blob_extraction_targets);
 727 }
 728
 729 #ifdef __WIN32__
 730 static const utf16lechar replacement_char = cpu_to_le16(0xfffd);
 731 #else
 732 static const utf16lechar replacement_char = cpu_to_le16('?');
 733 #endif
 734
 735 static bool
 736 file_name_valid(utf16lechar *name, size_t num_chars, bool fix)
 737 {
 738         size_t i;
 739
 740         if (num_chars == 0)
 741                 return true;
 742         for (i = 0; i < num_chars; i++) {
 743                 switch (name[i]) {
 744         #ifdef __WIN32__
 745                 case cpu_to_le16('\\'):
 746                 case cpu_to_le16(':'):
 747                 case cpu_to_le16('*'):
 748                 case cpu_to_le16('?'):
 749                 case cpu_to_le16('"'):
 750                 case cpu_to_le16('<'):
 751                 case cpu_to_le16('>'):
 752                 case cpu_to_le16('|'):
 753         #endif
 754                 case cpu_to_le16('/'):
 755                 case cpu_to_le16('\0'):
 756                         if (fix)
 757                                 name[i] = replacement_char;
 758                         else
 759                                 return false;
 760                 }
 761         }
 762
 763 #ifdef __WIN32__
 764         if (name[num_chars - 1] == cpu_to_le16(' ') ||
 765             name[num_chars - 1] == cpu_to_le16('.'))
 766         {
 767                 if (fix)
 768                         name[num_chars - 1] = replacement_char;
 769                 else
 770                         return false;
 771         }
 772 #endif
 773         return true;
 774 }
 775
 776 static int
 777 dentry_calculate_extraction_name(struct wim_dentry *dentry,
 778                                  struct apply_ctx *ctx)
 779 {
 780         int ret;
 781
 782         if (dentry_is_root(dentry))
 783                 return 0;
 784
 785 #ifdef WITH_NTFS_3G
 786         if (ctx->extract_flags & WIMLIB_EXTRACT_FLAG_NTFS) {
 787                 dentry->d_extraction_name = dentry->file_name;
 788                 dentry->d_extraction_name_nchars = dentry->file_name_nbytes /
 789                                                    sizeof(utf16lechar);
 790                 return 0;
 791         }
 792 #endif
 793
 794         if (!ctx->supported_features.case_sensitive_filenames) {
 795                 struct wim_dentry *other;
 796                 list_for_each_entry(other, &dentry->d_ci_conflict_list,
 797                                     d_ci_conflict_list)
 798                 {
 799                         if (will_extract_dentry(other)) {
 800                                 if (ctx->extract_flags &
 801                                     WIMLIB_EXTRACT_FLAG_ALL_CASE_CONFLICTS) {
 802                                         WARNING("\"%"TS"\" has the same "
 803                                                 "case-insensitive name as "
 804                                                 "\"%"TS"\"; extracting "
 805                                                 "dummy name instead",
 806                                                 dentry_full_path(dentry),
 807                                                 dentry_full_path(other));
 808                                         goto out_replace;
 809                                 } else {
 810                                         WARNING("Not extracting \"%"TS"\": "
 811                                                 "has same case-insensitive "
 812                                                 "name as \"%"TS"\"",
 813                                                 dentry_full_path(dentry),
 814                                                 dentry_full_path(other));
 815                                         goto skip_dentry;
 816                                 }
 817                         }
 818                 }
 819         }
 820
 821         if (file_name_valid(dentry->file_name, dentry->file_name_nbytes / 2, false)) {
 822                 ret = utf16le_get_tstr(dentry->file_name,
 823                                        dentry->file_name_nbytes,
 824                                        (const tchar **)&dentry->d_extraction_name,
 825                                        &dentry->d_extraction_name_nchars);
 826                 dentry->d_extraction_name_nchars /= sizeof(tchar);
 827                 return ret;
 828         } else {
 829                 if (ctx->extract_flags & WIMLIB_EXTRACT_FLAG_REPLACE_INVALID_FILENAMES)
 830                 {
 831                         WARNING("\"%"TS"\" has an invalid filename "
 832                                 "that is not supported on this platform; "
 833                                 "extracting dummy name instead",
 834                                 dentry_full_path(dentry));
 835                         goto out_replace;
 836                 } else {
 837                         WARNING("Not extracting \"%"TS"\": has an invalid filename "
 838                                 "that is not supported on this platform",
 839                                 dentry_full_path(dentry));
 840                         goto skip_dentry;
 841                 }
 842         }
 843
 844 out_replace:
 845         {
 846                 utf16lechar utf16_name_copy[dentry->file_name_nbytes / 2];
 847
 848                 memcpy(utf16_name_copy, dentry->file_name, dentry->file_name_nbytes);
 849                 file_name_valid(utf16_name_copy, dentry->file_name_nbytes / 2, true);
 850
 851                 const tchar *tchar_name;
 852                 size_t tchar_nchars;
 853
 854                 ret = utf16le_get_tstr(utf16_name_copy,
 855                                        dentry->file_name_nbytes,
 856                                        &tchar_name, &tchar_nchars);
 857                 if (ret)
 858                         return ret;
 859
 860                 tchar_nchars /= sizeof(tchar);
 861
 862                 size_t fixed_name_num_chars = tchar_nchars;
 863                 tchar fixed_name[tchar_nchars + 50];
 864
 865                 tmemcpy(fixed_name, tchar_name, tchar_nchars);
 866                 fixed_name_num_chars += tsprintf(fixed_name + tchar_nchars,
 867                                                  T(" (invalid filename #%lu)"),
 868                                                  ++ctx->invalid_sequence);
 869
 870                 utf16le_put_tstr(tchar_name);
 871
 872                 dentry->d_extraction_name = TSTRDUP(fixed_name);
 873                 if (!dentry->d_extraction_name)
 874                         return WIMLIB_ERR_NOMEM;
 875                 dentry->d_extraction_name_nchars = fixed_name_num_chars;
 876         }
 877         return 0;
 878
 879 skip_dentry:
 880         for_dentry_in_tree(dentry, dentry_delete_from_list, NULL);
 881         return 0;
 882 }
 883
 884 /*
 885  * Calculate the actual filename component at which each WIM dentry will be
 886  * extracted, with special handling for dentries that are unsupported by the
 887  * extraction backend or have invalid names.
 888  *
 889  * ctx->supported_features must be filled in.
 890  *
 891  * Possible error codes: WIMLIB_ERR_NOMEM, WIMLIB_ERR_INVALID_UTF16_STRING
 892  */
 893 static int
 894 dentry_list_calculate_extraction_names(struct list_head *dentry_list,
 895                                        struct apply_ctx *ctx)
 896 {
 897         struct list_head *prev, *cur;
 898
 899         /* Can't use list_for_each_entry() because a call to
 900          * dentry_calculate_extraction_name() may delete the current dentry and
 901          * its children from the list.  */
 902
 903         prev = dentry_list;
 904         for (;;) {
 905                 struct wim_dentry *dentry;
 906                 int ret;
 907
 908                 cur = prev->next;
 909                 if (cur == dentry_list)
 910                         break;
 911
 912                 dentry = list_entry(cur, struct wim_dentry, d_extraction_list_node);
 913
 914                 ret = dentry_calculate_extraction_name(dentry, ctx);
 915                 if (ret)
 916                         return ret;
 917
 918                 if (prev->next == cur)
 919                         prev = cur;
 920                 else
 921                         ; /* Current dentry and its children (which follow in
 922                              the list) were deleted.  prev stays the same.  */
 923         }
 924         return 0;
 925 }
 926
 927 static int
 928 dentry_resolve_streams(struct wim_dentry *dentry, int extract_flags,
 929                        struct blob_table *blob_table)
 930 {
 931         struct wim_inode *inode = dentry->d_inode;
 932         struct blob_descriptor *blob;
 933         int ret;
 934         bool force = false;
 935
 936         /* Special case:  when extracting from a pipe, the WIM blob table is
 937          * initially empty, so "resolving" an inode's streams is initially not
 938          * possible.  However, we still need to keep track of which blobs,
 939          * identified by SHA-1 message digests, need to be extracted, so we
 940          * "resolve" the inode's streams anyway by allocating a 'struct
 941          * blob_descriptor' for each one.  */
 942         if (extract_flags & WIMLIB_EXTRACT_FLAG_FROM_PIPE)
 943                 force = true;
 944         ret = inode_resolve_streams(inode, blob_table, force);
 945         if (ret)
 946                 return ret;
 947         for (unsigned i = 0; i < inode->i_num_streams; i++) {
 948                 blob = stream_blob_resolved(&inode->i_streams[i]);
 949                 if (blob)
 950                         blob->out_refcnt = 0;
 951         }
 952         return 0;
 953 }
 954
 955 /*
 956  * For each dentry to be extracted, resolve all streams in the corresponding
 957  * inode and set 'out_refcnt' in all referenced blob_descriptors to 0.
 958  *
 959  * Possible error codes: WIMLIB_ERR_RESOURCE_NOT_FOUND, WIMLIB_ERR_NOMEM.
 960  */
 961 static int
 962 dentry_list_resolve_streams(struct list_head *dentry_list,
 963                             struct apply_ctx *ctx)
 964 {
 965         struct wim_dentry *dentry;
 966         int ret;
 967
 968         list_for_each_entry(dentry, dentry_list, d_extraction_list_node) {
 969                 ret = dentry_resolve_streams(dentry,
 970                                              ctx->extract_flags,
 971                                              ctx->wim->blob_table);
 972                 if (ret)
 973                         return ret;
 974         }
 975         return 0;
 976 }
 977
 978 static int
 979 ref_stream(struct wim_inode_stream *strm, struct wim_dentry *dentry,
 980            struct apply_ctx *ctx)
 981 {
 982         struct wim_inode *inode = dentry->d_inode;
 983         struct blob_descriptor *blob = stream_blob_resolved(strm);
 984         struct blob_extraction_target *targets;
 985
 986         if (!blob)
 987                 return 0;
 988
 989         /* Tally the size only for each actual extraction of the stream (not
 990          * additional hard links to the inode).  */
 991         if (inode->i_visited && ctx->supported_features.hard_links)
 992                 return 0;
 993
 994         ctx->progress.extract.total_bytes += blob->size;
 995         ctx->progress.extract.total_streams++;
 996
 997         if (inode->i_visited)
 998                 return 0;
 999
1000         /* Add each blob to 'ctx->blob_list' only one time, regardless of how
1001          * many extraction targets it will have.  */
1002         if (blob->out_refcnt == 0) {
1003                 list_add_tail(&blob->extraction_list, &ctx->blob_list);
1004                 ctx->num_blobs_remaining++;
1005         }
1006
1007         /* Set this stream as an extraction target of 'blob'.  */
1008
1009         if (blob->out_refcnt < ARRAY_LEN(blob->inline_blob_extraction_targets)) {
1010                 targets = blob->inline_blob_extraction_targets;
1011         } else {
1012                 struct blob_extraction_target *prev_targets;
1013                 size_t alloc_blob_extraction_targets;
1014
1015                 if (blob->out_refcnt == ARRAY_LEN(blob->inline_blob_extraction_targets)) {
1016                         prev_targets = NULL;
1017                         alloc_blob_extraction_targets = ARRAY_LEN(blob->inline_blob_extraction_targets);
1018                 } else {
1019                         prev_targets = blob->blob_extraction_targets;
1020                         alloc_blob_extraction_targets = blob->alloc_blob_extraction_targets;
1021                 }
1022
1023                 if (blob->out_refcnt == alloc_blob_extraction_targets) {
1024                         alloc_blob_extraction_targets *= 2;
1025                         targets = REALLOC(prev_targets,
1026                                           alloc_blob_extraction_targets *
1027                                           sizeof(targets[0]));
1028                         if (!targets)
1029                                 return WIMLIB_ERR_NOMEM;
1030                         if (!prev_targets) {
1031                                 memcpy(targets,
1032                                        blob->inline_blob_extraction_targets,
1033                                        sizeof(blob->inline_blob_extraction_targets));
1034                         }
1035                         blob->blob_extraction_targets = targets;
1036                         blob->alloc_blob_extraction_targets = alloc_blob_extraction_targets;
1037                 }
1038                 targets = blob->blob_extraction_targets;
1039         }
1040         targets[blob->out_refcnt].inode = inode;
1041         targets[blob->out_refcnt].stream = strm;
1042         blob->out_refcnt++;
1043         return 0;
1044 }
1045
1046 static int
1047 ref_stream_if_needed(struct wim_dentry *dentry, struct wim_inode *inode,
1048                      struct wim_inode_stream *strm, struct apply_ctx *ctx)
1049 {
1050         bool need_stream = false;
1051         switch (strm->stream_type) {
1052         case STREAM_TYPE_DATA:
1053                 if (stream_is_named(strm)) {
1054                         /* Named data stream  */
1055                         if (ctx->supported_features.named_data_streams)
1056                                 need_stream = true;
1057                 } else if (!(inode->i_attributes & (FILE_ATTRIBUTE_DIRECTORY |
1058                                                     FILE_ATTRIBUTE_ENCRYPTED))
1059                            && !(inode_is_symlink(inode)
1060                                 && !ctx->supported_features.reparse_points
1061                                 && ctx->supported_features.symlink_reparse_points))
1062                 {
1063                         /*
1064                          * Unnamed data stream.  Skip if any of the following is true:
1065                          *
1066                          * - file is a directory
1067                          * - file is encrypted
1068                          * - backend needs to create the file as UNIX symlink
1069                          * - backend will extract the stream as externally backed
1070                          */
1071                         if (ctx->apply_ops->will_externally_back) {
1072                                 int ret = (*ctx->apply_ops->will_externally_back)(dentry, ctx);
1073                                 if (ret > 0) /* Error?  */
1074                                         return ret;
1075                                 if (ret < 0) /* Won't externally back?  */
1076                                         need_stream = true;
1077                         } else {
1078                                 need_stream = true;
1079                         }
1080                 }
1081                 break;
1082         case STREAM_TYPE_REPARSE_POINT:
1083                 wimlib_assert(inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT);
1084                 if (ctx->supported_features.reparse_points ||
1085                     (inode_is_symlink(inode) &&
1086                      ctx->supported_features.symlink_reparse_points))
1087                         need_stream = true;
1088                 break;
1089         case STREAM_TYPE_EFSRPC_RAW_DATA:
1090                 wimlib_assert(inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED);
1091                 if (inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY) {
1092                         if (ctx->supported_features.encrypted_directories)
1093                                 need_stream = true;
1094                 } else {
1095                         if (ctx->supported_features.encrypted_files)
1096                                 need_stream = true;
1097                 }
1098                 break;
1099         }
1100         if (need_stream)
1101                 return ref_stream(strm, dentry, ctx);
1102         return 0;
1103 }
1104
1105 static int
1106 dentry_ref_streams(struct wim_dentry *dentry, struct apply_ctx *ctx)
1107 {
1108         struct wim_inode *inode = dentry->d_inode;
1109         for (unsigned i = 0; i < inode->i_num_streams; i++) {
1110                 int ret = ref_stream_if_needed(dentry, inode,
1111                                                &inode->i_streams[i], ctx);
1112                 if (ret)
1113                         return ret;
1114         }
1115         inode->i_visited = 1;
1116         return 0;
1117 }
1118
1119 /*
1120  * Given a list of dentries to be extracted, build the list of blobs that need
1121  * to be extracted, and for each blob determine the streams to which that blob
1122  * will be extracted.
1123  *
1124  * This also initializes the extract progress info with byte and blob
1125  * information.
1126  *
1127  * ctx->supported_features must be filled in.
1128  */
1129 static int
1130 dentry_list_ref_streams(struct list_head *dentry_list, struct apply_ctx *ctx)
1131 {
1132         struct wim_dentry *dentry;
1133         int ret;
1134
1135         list_for_each_entry(dentry, dentry_list, d_extraction_list_node) {
1136                 ret = dentry_ref_streams(dentry, ctx);
1137                 if (ret)
1138                         return ret;
1139         }
1140         list_for_each_entry(dentry, dentry_list, d_extraction_list_node)
1141                 dentry->d_inode->i_visited = 0;
1142         return 0;
1143 }
1144
1145 static void
1146 dentry_list_build_inode_alias_lists(struct list_head *dentry_list)
1147 {
1148         struct wim_dentry *dentry;
1149         struct wim_inode *inode;
1150
1151         list_for_each_entry(dentry, dentry_list, d_extraction_list_node) {
1152                 inode = dentry->d_inode;
1153                 if (!inode->i_visited)
1154                         INIT_LIST_HEAD(&inode->i_extraction_aliases);
1155                 list_add_tail(&dentry->d_extraction_alias_node,
1156                               &inode->i_extraction_aliases);
1157                 inode->i_visited = 1;
1158         }
1159         list_for_each_entry(dentry, dentry_list, d_extraction_list_node)
1160                 dentry->d_inode->i_visited = 0;
1161 }
1162
1163 static void
1164 inode_tally_features(const struct wim_inode *inode,
1165                      struct wim_features *features)
1166 {
1167         if (inode->i_attributes & FILE_ATTRIBUTE_ARCHIVE)
1168                 features->archive_files++;
1169         if (inode->i_attributes & FILE_ATTRIBUTE_HIDDEN)
1170                 features->hidden_files++;
1171         if (inode->i_attributes & FILE_ATTRIBUTE_SYSTEM)
1172                 features->system_files++;
1173         if (inode->i_attributes & FILE_ATTRIBUTE_COMPRESSED)
1174                 features->compressed_files++;
1175         if (inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED) {
1176                 if (inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY)
1177                         features->encrypted_directories++;
1178                 else
1179                         features->encrypted_files++;
1180         }
1181         if (inode->i_attributes & FILE_ATTRIBUTE_NOT_CONTENT_INDEXED)
1182                 features->not_context_indexed_files++;
1183         if (inode->i_attributes & FILE_ATTRIBUTE_SPARSE_FILE)
1184                 features->sparse_files++;
1185         if (inode_has_named_data_stream(inode))
1186                 features->named_data_streams++;
1187         if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
1188                 features->reparse_points++;
1189                 if (inode_is_symlink(inode))
1190                         features->symlink_reparse_points++;
1191                 else
1192                         features->other_reparse_points++;
1193         }
1194         if (inode->i_security_id != -1)
1195                 features->security_descriptors++;
1196         if (inode_has_unix_data(inode))
1197                 features->unix_data++;
1198 }
1199
1200 /* Tally features necessary to extract a dentry and the corresponding inode.  */
1201 static void
1202 dentry_tally_features(struct wim_dentry *dentry, struct wim_features *features)
1203 {
1204         struct wim_inode *inode = dentry->d_inode;
1205
1206         if (dentry_has_short_name(dentry))
1207                 features->short_names++;
1208
1209         if (inode->i_visited) {
1210                 features->hard_links++;
1211         } else {
1212                 inode_tally_features(inode, features);
1213                 inode->i_visited = 1;
1214         }
1215 }
1216
1217 /* Tally the features necessary to extract the specified dentries.  */
1218 static void
1219 dentry_list_get_features(struct list_head *dentry_list,
1220                          struct wim_features *features)
1221 {
1222         struct wim_dentry *dentry;
1223
1224         list_for_each_entry(dentry, dentry_list, d_extraction_list_node)
1225                 dentry_tally_features(dentry, features);
1226
1227         list_for_each_entry(dentry, dentry_list, d_extraction_list_node)
1228                 dentry->d_inode->i_visited = 0;
1229 }
1230
1231 static int
1232 do_feature_check(const struct wim_features *required_features,
1233                  const struct wim_features *supported_features,
1234                  int extract_flags)
1235 {
1236         /* Encrypted files.  */
1237         if (required_features->encrypted_files &&
1238             !supported_features->encrypted_files)
1239                 WARNING("Ignoring EFS-encrypted data of %lu files",
1240                         required_features->encrypted_files);
1241
1242         /* Named data streams.  */
1243         if (required_features->named_data_streams &&
1244             !supported_features->named_data_streams)
1245                 WARNING("Ignoring named data streams of %lu files",
1246                         required_features->named_data_streams);
1247
1248         /* File attributes.  */
1249         if (!(extract_flags & WIMLIB_EXTRACT_FLAG_NO_ATTRIBUTES)) {
1250                 /* Note: Don't bother the user about FILE_ATTRIBUTE_ARCHIVE.
1251                  * We're an archive program, so theoretically we can do what we
1252                  * want with it.  */
1253
1254                 if (required_features->hidden_files &&
1255                     !supported_features->hidden_files)
1256                         WARNING("Ignoring FILE_ATTRIBUTE_HIDDEN of %lu files",
1257                                 required_features->hidden_files);
1258
1259                 if (required_features->system_files &&
1260                     !supported_features->system_files)
1261                         WARNING("Ignoring FILE_ATTRIBUTE_SYSTEM of %lu files",
1262                                 required_features->system_files);
1263
1264                 if (required_features->compressed_files &&
1265                     !supported_features->compressed_files)
1266                         WARNING("Ignoring FILE_ATTRIBUTE_COMPRESSED of %lu files",
1267                                 required_features->compressed_files);
1268
1269                 if (required_features->not_context_indexed_files &&
1270                     !supported_features->not_context_indexed_files)
1271                         WARNING("Ignoring FILE_ATTRIBUTE_NOT_CONTENT_INDEXED of %lu files",
1272                                 required_features->not_context_indexed_files);
1273
1274                 if (required_features->sparse_files &&
1275                     !supported_features->sparse_files)
1276                         WARNING("Ignoring FILE_ATTRIBUTE_SPARSE_FILE of %lu files",
1277                                 required_features->sparse_files);
1278
1279                 if (required_features->encrypted_directories &&
1280                     !supported_features->encrypted_directories)
1281                         WARNING("Ignoring FILE_ATTRIBUTE_ENCRYPTED of %lu directories",
1282                                 required_features->encrypted_directories);
1283         }
1284
1285         /* Hard links.  */
1286         if (required_features->hard_links && !supported_features->hard_links)
1287                 WARNING("Extracting %lu hard links as independent files",
1288                         required_features->hard_links);
1289
1290         /* Symbolic links and reparse points.  */
1291         if ((extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_SYMLINKS) &&
1292             required_features->symlink_reparse_points &&
1293             !supported_features->symlink_reparse_points &&
1294             !supported_features->reparse_points)
1295         {
1296                 ERROR("Extraction backend does not support symbolic links!");
1297                 return WIMLIB_ERR_UNSUPPORTED;
1298         }
1299         if (required_features->reparse_points &&
1300             !supported_features->reparse_points)
1301         {
1302                 if (supported_features->symlink_reparse_points) {
1303                         if (required_features->other_reparse_points) {
1304                                 WARNING("Ignoring reparse data of %lu non-symlink/junction files",
1305                                         required_features->other_reparse_points);
1306                         }
1307                 } else {
1308                         WARNING("Ignoring reparse data of %lu files",
1309                                 required_features->reparse_points);
1310                 }
1311         }
1312
1313         /* Security descriptors.  */
1314         if (((extract_flags & (WIMLIB_EXTRACT_FLAG_STRICT_ACLS |
1315                                WIMLIB_EXTRACT_FLAG_UNIX_DATA))
1316              == WIMLIB_EXTRACT_FLAG_STRICT_ACLS) &&
1317             required_features->security_descriptors &&
1318             !supported_features->security_descriptors)
1319         {
1320                 ERROR("Extraction backend does not support security descriptors!");
1321                 return WIMLIB_ERR_UNSUPPORTED;
1322         }
1323         if (!(extract_flags & WIMLIB_EXTRACT_FLAG_NO_ACLS) &&
1324             required_features->security_descriptors &&
1325             !supported_features->security_descriptors)
1326                 WARNING("Ignoring Windows NT security descriptors of %lu files",
1327                         required_features->security_descriptors);
1328
1329         /* UNIX data.  */
1330         if ((extract_flags & WIMLIB_EXTRACT_FLAG_UNIX_DATA) &&
1331             required_features->unix_data && !supported_features->unix_data)
1332         {
1333                 ERROR("Extraction backend does not support UNIX data!");
1334                 return WIMLIB_ERR_UNSUPPORTED;
1335         }
1336
1337         if (required_features->unix_data &&
1338             !(extract_flags & WIMLIB_EXTRACT_FLAG_UNIX_DATA))
1339         {
1340                 WARNING("Ignoring UNIX metadata of %lu files",
1341                         required_features->unix_data);
1342         }
1343
1344         /* DOS Names.  */
1345         if (required_features->short_names &&
1346             !supported_features->short_names)
1347         {
1348                 if (extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_SHORT_NAMES) {
1349                         ERROR("Extraction backend does not support DOS names!");
1350                         return WIMLIB_ERR_UNSUPPORTED;
1351                 }
1352                 WARNING("Ignoring DOS names of %lu files",
1353                         required_features->short_names);
1354         }
1355
1356         /* Timestamps.  */
1357         if ((extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_TIMESTAMPS) &&
1358             !supported_features->timestamps)
1359         {
1360                 ERROR("Extraction backend does not support timestamps!");
1361                 return WIMLIB_ERR_UNSUPPORTED;
1362         }
1363
1364         return 0;
1365 }
1366
1367 static const struct apply_operations *
1368 select_apply_operations(int extract_flags)
1369 {
1370 #ifdef WITH_NTFS_3G
1371         if (extract_flags & WIMLIB_EXTRACT_FLAG_NTFS)
1372                 return &ntfs_3g_apply_ops;
1373 #endif
1374 #ifdef __WIN32__
1375         return &win32_apply_ops;
1376 #else
1377         return &unix_apply_ops;
1378 #endif
1379 }
1380
1381 static int
1382 extract_trees(WIMStruct *wim, struct wim_dentry **trees, size_t num_trees,
1383               const tchar *target, int extract_flags)
1384 {
1385         const struct apply_operations *ops;
1386         struct apply_ctx *ctx;
1387         int ret;
1388         LIST_HEAD(dentry_list);
1389
1390         if (extract_flags & WIMLIB_EXTRACT_FLAG_TO_STDOUT) {
1391                 ret = extract_dentries_to_stdout(trees, num_trees,
1392                                                  wim->blob_table);
1393                 goto out;
1394         }
1395
1396         num_trees = remove_duplicate_trees(trees, num_trees);
1397         num_trees = remove_contained_trees(trees, num_trees);
1398
1399         ops = select_apply_operations(extract_flags);
1400
1401         if (num_trees > 1 && ops->single_tree_only) {
1402                 ERROR("Extracting multiple directory trees "
1403                       "at once is not supported in %s extraction mode!",
1404                       ops->name);
1405                 ret = WIMLIB_ERR_UNSUPPORTED;
1406                 goto out;
1407         }
1408
1409         ctx = CALLOC(1, ops->context_size);
1410         if (!ctx) {
1411                 ret = WIMLIB_ERR_NOMEM;
1412                 goto out;
1413         }
1414
1415         ctx->wim = wim;
1416         ctx->target = target;
1417         ctx->target_nchars = tstrlen(target);
1418         ctx->extract_flags = extract_flags;
1419         if (ctx->wim->progfunc) {
1420                 ctx->progfunc = ctx->wim->progfunc;
1421                 ctx->progctx = ctx->wim->progctx;
1422                 ctx->progress.extract.image = wim->current_image;
1423                 ctx->progress.extract.extract_flags = (extract_flags &
1424                                                        WIMLIB_EXTRACT_MASK_PUBLIC);
1425                 ctx->progress.extract.wimfile_name = wim->filename;
1426                 ctx->progress.extract.image_name = wimlib_get_image_name(wim,
1427                                                                          wim->current_image);
1428                 ctx->progress.extract.target = target;
1429         }
1430         INIT_LIST_HEAD(&ctx->blob_list);
1431         filedes_invalidate(&ctx->tmpfile_fd);
1432         ctx->apply_ops = ops;
1433
1434         ret = (*ops->get_supported_features)(target, &ctx->supported_features);
1435         if (ret)
1436                 goto out_cleanup;
1437
1438         build_dentry_list(&dentry_list, trees, num_trees,
1439                           !(extract_flags &
1440                             WIMLIB_EXTRACT_FLAG_NO_PRESERVE_DIR_STRUCTURE));
1441
1442         dentry_list_get_features(&dentry_list, &ctx->required_features);
1443
1444         ret = do_feature_check(&ctx->required_features, &ctx->supported_features,
1445                                ctx->extract_flags);
1446         if (ret)
1447                 goto out_cleanup;
1448
1449         ret = dentry_list_calculate_extraction_names(&dentry_list, ctx);
1450         if (ret)
1451                 goto out_cleanup;
1452
1453         if (unlikely(list_empty(&dentry_list))) {
1454                 WARNING("There is nothing to extract!");
1455                 goto out_cleanup;
1456         }
1457
1458         ret = dentry_list_resolve_streams(&dentry_list, ctx);
1459         if (ret)
1460                 goto out_cleanup;
1461
1462         dentry_list_build_inode_alias_lists(&dentry_list);
1463
1464         ret = dentry_list_ref_streams(&dentry_list, ctx);
1465         if (ret)
1466                 goto out_cleanup;
1467
1468         if (extract_flags & WIMLIB_EXTRACT_FLAG_FROM_PIPE) {
1469                 /* When extracting from a pipe, the number of bytes of data to
1470                  * extract can't be determined in the normal way (examining the
1471                  * blob table), since at this point all we have is a set of
1472                  * SHA-1 message digests of blobs that need to be extracted.
1473                  * However, we can get a reasonably accurate estimate by taking
1474                  * <TOTALBYTES> from the corresponding <IMAGE> in the WIM XML
1475                  * data.  This does assume that a full image is being extracted,
1476                  * but currently there is no API for doing otherwise.  (Also,
1477                  * subtract <HARDLINKBYTES> from this if hard links are
1478                  * supported by the extraction mode.)  */
1479                 ctx->progress.extract.total_bytes =
1480                         wim_info_get_image_total_bytes(wim->wim_info,
1481                                                        wim->current_image);
1482                 if (ctx->supported_features.hard_links) {
1483                         ctx->progress.extract.total_bytes -=
1484                                 wim_info_get_image_hard_link_bytes(wim->wim_info,
1485                                                                    wim->current_image);
1486                 }
1487         }
1488
1489         ret = extract_progress(ctx,
1490                                ((extract_flags & WIMLIB_EXTRACT_FLAG_IMAGEMODE) ?
1491                                        WIMLIB_PROGRESS_MSG_EXTRACT_IMAGE_BEGIN :
1492                                        WIMLIB_PROGRESS_MSG_EXTRACT_TREE_BEGIN));
1493         if (ret)
1494                 goto out_cleanup;
1495
1496         ret = (*ops->extract)(&dentry_list, ctx);
1497         if (ret)
1498                 goto out_cleanup;
1499
1500         if (ctx->progress.extract.completed_bytes <
1501             ctx->progress.extract.total_bytes)
1502         {
1503                 ctx->progress.extract.completed_bytes =
1504                         ctx->progress.extract.total_bytes;
1505                 ret = extract_progress(ctx, WIMLIB_PROGRESS_MSG_EXTRACT_STREAMS);
1506                 if (ret)
1507                         goto out_cleanup;
1508         }
1509
1510         ret = extract_progress(ctx,
1511                                ((extract_flags & WIMLIB_EXTRACT_FLAG_IMAGEMODE) ?
1512                                        WIMLIB_PROGRESS_MSG_EXTRACT_IMAGE_END :
1513                                        WIMLIB_PROGRESS_MSG_EXTRACT_TREE_END));
1514 out_cleanup:
1515         destroy_blob_list(&ctx->blob_list);
1516         destroy_dentry_list(&dentry_list);
1517         FREE(ctx);
1518 out:
1519         return ret;
1520 }
1521
1522 static int
1523 mkdir_if_needed(const tchar *target)
1524 {
1525         if (!tmkdir(target, 0755))
1526                 return 0;
1527
1528         if (errno == EEXIST)
1529                 return 0;
1530
1531 #ifdef __WIN32__
1532         /* _wmkdir() fails with EACCES if called on a drive root directory.  */
1533         if (errno == EACCES)
1534                 return 0;
1535 #endif
1536
1537         ERROR_WITH_ERRNO("Failed to create directory \"%"TS"\"", target);
1538         return WIMLIB_ERR_MKDIR;
1539 }
1540
1541 /* Make sure the extraction flags make sense, and update them if needed.  */
1542 static int
1543 check_extract_flags(const WIMStruct *wim, int *extract_flags_p)
1544 {
1545         int extract_flags = *extract_flags_p;
1546
1547         /* Check for invalid flag combinations  */
1548
1549         if ((extract_flags &
1550              (WIMLIB_EXTRACT_FLAG_NO_ACLS |
1551               WIMLIB_EXTRACT_FLAG_STRICT_ACLS)) == (WIMLIB_EXTRACT_FLAG_NO_ACLS |
1552                                                     WIMLIB_EXTRACT_FLAG_STRICT_ACLS))
1553                 return WIMLIB_ERR_INVALID_PARAM;
1554
1555         if ((extract_flags &
1556              (WIMLIB_EXTRACT_FLAG_RPFIX |
1557               WIMLIB_EXTRACT_FLAG_NORPFIX)) == (WIMLIB_EXTRACT_FLAG_RPFIX |
1558                                                 WIMLIB_EXTRACT_FLAG_NORPFIX))
1559                 return WIMLIB_ERR_INVALID_PARAM;
1560
1561 #ifndef WITH_NTFS_3G
1562         if (extract_flags & WIMLIB_EXTRACT_FLAG_NTFS) {
1563                 ERROR("wimlib was compiled without support for NTFS-3g, so\n"
1564                       "        it cannot apply a WIM image directly to an NTFS volume.");
1565                 return WIMLIB_ERR_UNSUPPORTED;
1566         }
1567 #endif
1568
1569         if (extract_flags & WIMLIB_EXTRACT_FLAG_WIMBOOT) {
1570 #ifdef __WIN32__
1571                 if (!wim->filename)
1572                         return WIMLIB_ERR_NO_FILENAME;
1573 #else
1574                 ERROR("WIMBoot extraction is only supported on Windows!");
1575                 return WIMLIB_ERR_UNSUPPORTED;
1576 #endif
1577         }
1578
1579
1580         if ((extract_flags & (WIMLIB_EXTRACT_FLAG_RPFIX |
1581                               WIMLIB_EXTRACT_FLAG_NORPFIX |
1582                               WIMLIB_EXTRACT_FLAG_IMAGEMODE)) ==
1583                                         WIMLIB_EXTRACT_FLAG_IMAGEMODE)
1584         {
1585                 /* For full-image extraction, do reparse point fixups by default
1586                  * if the WIM header says they are enabled.  */
1587                 if (wim->hdr.flags & WIM_HDR_FLAG_RP_FIX)
1588                         extract_flags |= WIMLIB_EXTRACT_FLAG_RPFIX;
1589         }
1590
1591         *extract_flags_p = extract_flags;
1592         return 0;
1593 }
1594
1595 static u32
1596 get_wildcard_flags(int extract_flags)
1597 {
1598         u32 wildcard_flags = 0;
1599
1600         if (extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_GLOB)
1601                 wildcard_flags |= WILDCARD_FLAG_ERROR_IF_NO_MATCH;
1602         else
1603                 wildcard_flags |= WILDCARD_FLAG_WARN_IF_NO_MATCH;
1604
1605         if (default_ignore_case)
1606                 wildcard_flags |= WILDCARD_FLAG_CASE_INSENSITIVE;
1607
1608         return wildcard_flags;
1609 }
1610
1611 struct append_dentry_ctx {
1612         struct wim_dentry **dentries;
1613         size_t num_dentries;
1614         size_t num_alloc_dentries;
1615 };
1616
1617 static int
1618 append_dentry_cb(struct wim_dentry *dentry, void *_ctx)
1619 {
1620         struct append_dentry_ctx *ctx = _ctx;
1621
1622         if (ctx->num_dentries == ctx->num_alloc_dentries) {
1623                 struct wim_dentry **new_dentries;
1624                 size_t new_length;
1625
1626                 new_length = max(ctx->num_alloc_dentries + 8,
1627                                  ctx->num_alloc_dentries * 3 / 2);
1628                 new_dentries = REALLOC(ctx->dentries,
1629                                        new_length * sizeof(ctx->dentries[0]));
1630                 if (new_dentries == NULL)
1631                         return WIMLIB_ERR_NOMEM;
1632                 ctx->dentries = new_dentries;
1633                 ctx->num_alloc_dentries = new_length;
1634         }
1635         ctx->dentries[ctx->num_dentries++] = dentry;
1636         return 0;
1637 }
1638
1639 static int
1640 do_wimlib_extract_paths(WIMStruct *wim, int image, const tchar *target,
1641                         const tchar * const *paths, size_t num_paths,
1642                         int extract_flags)
1643 {
1644         int ret;
1645         struct wim_dentry **trees;
1646         size_t num_trees;
1647
1648         if (wim == NULL || target == NULL || target[0] == T('\0') ||
1649             (num_paths != 0 && paths == NULL))
1650                 return WIMLIB_ERR_INVALID_PARAM;
1651
1652         ret = check_extract_flags(wim, &extract_flags);
1653         if (ret)
1654                 return ret;
1655
1656         ret = select_wim_image(wim, image);
1657         if (ret)
1658                 return ret;
1659
1660         ret = wim_checksum_unhashed_blobs(wim);
1661         if (ret)
1662                 return ret;
1663
1664         if ((extract_flags & (WIMLIB_EXTRACT_FLAG_NTFS |
1665                               WIMLIB_EXTRACT_FLAG_NO_PRESERVE_DIR_STRUCTURE)) ==
1666             (WIMLIB_EXTRACT_FLAG_NO_PRESERVE_DIR_STRUCTURE))
1667         {
1668                 ret = mkdir_if_needed(target);
1669                 if (ret)
1670                         return ret;
1671         }
1672
1673         if (extract_flags & WIMLIB_EXTRACT_FLAG_GLOB_PATHS) {
1674
1675                 struct append_dentry_ctx append_dentry_ctx = {
1676                         .dentries = NULL,
1677                         .num_dentries = 0,
1678                         .num_alloc_dentries = 0,
1679                 };
1680
1681                 u32 wildcard_flags = get_wildcard_flags(extract_flags);
1682
1683                 for (size_t i = 0; i < num_paths; i++) {
1684                         tchar *path = canonicalize_wim_path(paths[i]);
1685                         if (path == NULL) {
1686                                 ret = WIMLIB_ERR_NOMEM;
1687                                 trees = append_dentry_ctx.dentries;
1688                                 goto out_free_trees;
1689                         }
1690                         ret = expand_wildcard(wim, path,
1691                                               append_dentry_cb,
1692                                               &append_dentry_ctx,
1693                                               wildcard_flags);
1694                         FREE(path);
1695                         if (ret) {
1696                                 trees = append_dentry_ctx.dentries;
1697                                 goto out_free_trees;
1698                         }
1699                 }
1700                 trees = append_dentry_ctx.dentries;
1701                 num_trees = append_dentry_ctx.num_dentries;
1702         } else {
1703                 trees = MALLOC(num_paths * sizeof(trees[0]));
1704                 if (trees == NULL)
1705                         return WIMLIB_ERR_NOMEM;
1706
1707                 for (size_t i = 0; i < num_paths; i++) {
1708
1709                         tchar *path = canonicalize_wim_path(paths[i]);
1710                         if (path == NULL) {
1711                                 ret = WIMLIB_ERR_NOMEM;
1712                                 goto out_free_trees;
1713                         }
1714
1715                         trees[i] = get_dentry(wim, path,
1716                                               WIMLIB_CASE_PLATFORM_DEFAULT);
1717                         FREE(path);
1718                         if (trees[i] == NULL) {
1719                                   ERROR("Path \"%"TS"\" does not exist "
1720                                         "in WIM image %d",
1721                                         paths[i], wim->current_image);
1722                                   ret = WIMLIB_ERR_PATH_DOES_NOT_EXIST;
1723                                   goto out_free_trees;
1724                         }
1725                 }
1726                 num_trees = num_paths;
1727         }
1728
1729         if (num_trees == 0) {
1730                 ret = 0;
1731                 goto out_free_trees;
1732         }
1733
1734         ret = extract_trees(wim, trees, num_trees, target, extract_flags);
1735 out_free_trees:
1736         FREE(trees);
1737         return ret;
1738 }
1739
1740 static int
1741 extract_single_image(WIMStruct *wim, int image,
1742                      const tchar *target, int extract_flags)
1743 {
1744         const tchar *path = WIMLIB_WIM_ROOT_PATH;
1745         extract_flags |= WIMLIB_EXTRACT_FLAG_IMAGEMODE;
1746         return do_wimlib_extract_paths(wim, image, target, &path, 1, extract_flags);
1747 }
1748
1749 static const tchar * const filename_forbidden_chars =
1750 T(
1751 #ifdef __WIN32__
1752 "<>:\"/\\|?*"
1753 #else
1754 "/"
1755 #endif
1756 );
1757
1758 /* This function checks if it is okay to use a WIM image's name as a directory
1759  * name.  */
1760 static bool
1761 image_name_ok_as_dir(const tchar *image_name)
1762 {
1763         return image_name && *image_name &&
1764                 !tstrpbrk(image_name, filename_forbidden_chars) &&
1765                 tstrcmp(image_name, T(".")) &&
1766                 tstrcmp(image_name, T(".."));
1767 }
1768
1769 /* Extracts all images from the WIM to the directory @target, with the images
1770  * placed in subdirectories named by their image names. */
1771 static int
1772 extract_all_images(WIMStruct *wim, const tchar *target, int extract_flags)
1773 {
1774         size_t image_name_max_len = max(xml_get_max_image_name_len(wim), 20);
1775         size_t output_path_len = tstrlen(target);
1776         tchar buf[output_path_len + 1 + image_name_max_len + 1];
1777         int ret;
1778         int image;
1779         const tchar *image_name;
1780
1781         if (extract_flags & WIMLIB_EXTRACT_FLAG_NTFS) {
1782                 ERROR("Cannot extract multiple images in NTFS extraction mode.");
1783                 return WIMLIB_ERR_INVALID_PARAM;
1784         }
1785
1786         ret = mkdir_if_needed(target);
1787         if (ret)
1788                 return ret;
1789         tmemcpy(buf, target, output_path_len);
1790         buf[output_path_len] = OS_PREFERRED_PATH_SEPARATOR;
1791         for (image = 1; image <= wim->hdr.image_count; image++) {
1792                 image_name = wimlib_get_image_name(wim, image);
1793                 if (image_name_ok_as_dir(image_name)) {
1794                         tstrcpy(buf + output_path_len + 1, image_name);
1795                 } else {
1796                         /* Image name is empty or contains forbidden characters.
1797                          * Use image number instead. */
1798                         tsprintf(buf + output_path_len + 1, T("%d"), image);
1799                 }
1800                 ret = extract_single_image(wim, image, buf, extract_flags);
1801                 if (ret)
1802                         return ret;
1803         }
1804         return 0;
1805 }
1806
1807 static int
1808 do_wimlib_extract_image(WIMStruct *wim, int image, const tchar *target,
1809                         int extract_flags)
1810 {
1811         if (extract_flags & (WIMLIB_EXTRACT_FLAG_NO_PRESERVE_DIR_STRUCTURE |
1812                              WIMLIB_EXTRACT_FLAG_TO_STDOUT |
1813                              WIMLIB_EXTRACT_FLAG_GLOB_PATHS))
1814                 return WIMLIB_ERR_INVALID_PARAM;
1815
1816         if (image == WIMLIB_ALL_IMAGES)
1817                 return extract_all_images(wim, target, extract_flags);
1818         else
1819                 return extract_single_image(wim, image, target, extract_flags);
1820 }
1821
1822
1823 /****************************************************************************
1824  *                          Extraction API                                  *
1825  ****************************************************************************/
1826
1827 WIMLIBAPI int
1828 wimlib_extract_paths(WIMStruct *wim, int image, const tchar *target,
1829                      const tchar * const *paths, size_t num_paths,
1830                      int extract_flags)
1831 {
1832         if (extract_flags & ~WIMLIB_EXTRACT_MASK_PUBLIC)
1833                 return WIMLIB_ERR_INVALID_PARAM;
1834
1835         return do_wimlib_extract_paths(wim, image, target, paths, num_paths,
1836                                        extract_flags);
1837 }
1838
1839 WIMLIBAPI int
1840 wimlib_extract_pathlist(WIMStruct *wim, int image, const tchar *target,
1841                         const tchar *path_list_file, int extract_flags)
1842 {
1843         int ret;
1844         tchar **paths;
1845         size_t num_paths;
1846         void *mem;
1847
1848         ret = read_path_list_file(path_list_file, &paths, &num_paths, &mem);
1849         if (ret) {
1850                 ERROR("Failed to read path list file \"%"TS"\"",
1851                       path_list_file);
1852                 return ret;
1853         }
1854
1855         ret = wimlib_extract_paths(wim, image, target,
1856                                    (const tchar * const *)paths, num_paths,
1857                                    extract_flags);
1858         FREE(paths);
1859         FREE(mem);
1860         return ret;
1861 }
1862
1863 WIMLIBAPI int
1864 wimlib_extract_image_from_pipe_with_progress(int pipe_fd,
1865                                              const tchar *image_num_or_name,
1866                                              const tchar *target,
1867                                              int extract_flags,
1868                                              wimlib_progress_func_t progfunc,
1869                                              void *progctx)
1870 {
1871         int ret;
1872         WIMStruct *pwm;
1873         struct filedes *in_fd;
1874         int image;
1875         unsigned i;
1876
1877         if (extract_flags & ~WIMLIB_EXTRACT_MASK_PUBLIC)
1878                 return WIMLIB_ERR_INVALID_PARAM;
1879
1880         /* Read the WIM header from the pipe and get a WIMStruct to represent
1881          * the pipable WIM.  Caveats:  Unlike getting a WIMStruct with
1882          * wimlib_open_wim(), getting a WIMStruct in this way will result in an
1883          * empty blob table, no XML data read, and no filename set.  */
1884         ret = open_wim_as_WIMStruct(&pipe_fd, WIMLIB_OPEN_FLAG_FROM_PIPE, &pwm,
1885                                     progfunc, progctx);
1886         if (ret)
1887                 return ret;
1888
1889         /* Sanity check to make sure this is a pipable WIM.  */
1890         if (pwm->hdr.magic != PWM_MAGIC) {
1891                 ERROR("The WIM being read from file descriptor %d "
1892                       "is not pipable!", pipe_fd);
1893                 ret = WIMLIB_ERR_NOT_PIPABLE;
1894                 goto out_wimlib_free;
1895         }
1896
1897         /* Sanity check to make sure the first part of a pipable split WIM is
1898          * sent over the pipe first.  */
1899         if (pwm->hdr.part_number != 1) {
1900                 ERROR("The first part of the split WIM must be "
1901                       "sent over the pipe first.");
1902                 ret = WIMLIB_ERR_INVALID_PIPABLE_WIM;
1903                 goto out_wimlib_free;
1904         }
1905
1906         in_fd = &pwm->in_fd;
1907         wimlib_assert(in_fd->offset == WIM_HEADER_DISK_SIZE);
1908
1909         /* As mentioned, the WIMStruct we created from the pipe does not have
1910          * XML data yet.  Fix this by reading the extra copy of the XML data
1911          * that directly follows the header in pipable WIMs.  (Note: see
1912          * write_pipable_wim() for more details about the format of pipable
1913          * WIMs.)  */
1914         {
1915                 struct blob_descriptor xml_blob;
1916                 struct wim_resource_descriptor xml_rdesc;
1917                 ret = read_pwm_blob_header(pwm, &xml_blob, &xml_rdesc, 0, NULL);
1918                 if (ret)
1919                         goto out_wimlib_free;
1920
1921                 if (!xml_blob.is_metadata) {
1922                         ERROR("Expected XML data, but found non-metadata resource.");
1923                         ret = WIMLIB_ERR_INVALID_PIPABLE_WIM;
1924                         goto out_wimlib_free;
1925                 }
1926
1927                 wim_res_desc_to_hdr(&xml_rdesc, &pwm->hdr.xml_data_reshdr);
1928
1929                 ret = read_wim_xml_data(pwm);
1930                 if (ret)
1931                         goto out_wimlib_free;
1932
1933                 if (wim_info_get_num_images(pwm->wim_info) != pwm->hdr.image_count) {
1934                         ERROR("Image count in XML data is not the same as in WIM header.");
1935                         ret = WIMLIB_ERR_IMAGE_COUNT;
1936                         goto out_wimlib_free;
1937                 }
1938         }
1939
1940         /* Get image index (this may use the XML data that was just read to
1941          * resolve an image name).  */
1942         if (image_num_or_name) {
1943                 image = wimlib_resolve_image(pwm, image_num_or_name);
1944                 if (image == WIMLIB_NO_IMAGE) {
1945                         ERROR("\"%"TS"\" is not a valid image in the pipable WIM!",
1946                               image_num_or_name);
1947                         ret = WIMLIB_ERR_INVALID_IMAGE;
1948                         goto out_wimlib_free;
1949                 } else if (image == WIMLIB_ALL_IMAGES) {
1950                         ERROR("Applying all images from a pipe is not supported!");
1951                         ret = WIMLIB_ERR_INVALID_IMAGE;
1952                         goto out_wimlib_free;
1953                 }
1954         } else {
1955                 if (pwm->hdr.image_count != 1) {
1956                         ERROR("No image was specified, but the pipable WIM "
1957                               "did not contain exactly 1 image");
1958                         ret = WIMLIB_ERR_INVALID_IMAGE;
1959                         goto out_wimlib_free;
1960                 }
1961                 image = 1;
1962         }
1963
1964         /* Load the needed metadata resource.  */
1965         for (i = 1; i <= pwm->hdr.image_count; i++) {
1966                 struct blob_descriptor *metadata_blob;
1967                 struct wim_image_metadata *imd;
1968                 struct wim_resource_descriptor *metadata_rdesc;
1969
1970                 metadata_blob = new_blob_descriptor();
1971                 if (metadata_blob == NULL) {
1972                         ret = WIMLIB_ERR_NOMEM;
1973                         goto out_wimlib_free;
1974                 }
1975                 metadata_rdesc = MALLOC(sizeof(struct wim_resource_descriptor));
1976                 if (metadata_rdesc == NULL) {
1977                         ret = WIMLIB_ERR_NOMEM;
1978                         free_blob_descriptor(metadata_blob);
1979                         goto out_wimlib_free;
1980                 }
1981
1982                 ret = read_pwm_blob_header(pwm, metadata_blob, metadata_rdesc, 0, NULL);
1983                 imd = pwm->image_metadata[i - 1];
1984                 imd->metadata_blob = metadata_blob;
1985                 if (ret) {
1986                         FREE(metadata_rdesc);
1987                         goto out_wimlib_free;
1988                 }
1989
1990                 if (!metadata_blob->is_metadata) {
1991                         ERROR("Expected metadata resource, but found "
1992                               "non-metadata resource.");
1993                         ret = WIMLIB_ERR_INVALID_PIPABLE_WIM;
1994                         goto out_wimlib_free;
1995                 }
1996
1997                 if (i == image) {
1998                         /* Metadata resource is for the image being extracted.
1999                          * Parse it and save the metadata in memory.  */
2000                         ret = read_metadata_resource(imd);
2001                         if (ret)
2002                                 goto out_wimlib_free;
2003                         imd->modified = 1;
2004                 } else {
2005                         /* Metadata resource is not for the image being
2006                          * extracted.  Skip over it.  */
2007                         ret = skip_wim_resource(metadata_rdesc);
2008                         if (ret)
2009                                 goto out_wimlib_free;
2010                 }
2011         }
2012         /* Extract the image.  */
2013         extract_flags |= WIMLIB_EXTRACT_FLAG_FROM_PIPE;
2014         ret = do_wimlib_extract_image(pwm, image, target, extract_flags);
2015         /* Clean up and return.  */
2016 out_wimlib_free:
2017         wimlib_free(pwm);
2018         return ret;
2019 }
2020
2021
2022 WIMLIBAPI int
2023 wimlib_extract_image_from_pipe(int pipe_fd, const tchar *image_num_or_name,
2024                                const tchar *target, int extract_flags)
2025 {
2026         return wimlib_extract_image_from_pipe_with_progress(pipe_fd,
2027                                                             image_num_or_name,
2028                                                             target,
2029                                                             extract_flags,
2030                                                             NULL,
2031                                                             NULL);
2032 }
2033
2034 WIMLIBAPI int
2035 wimlib_extract_image(WIMStruct *wim, int image, const tchar *target,
2036                      int extract_flags)
2037 {
2038         if (extract_flags & ~WIMLIB_EXTRACT_MASK_PUBLIC)
2039                 return WIMLIB_ERR_INVALID_PARAM;
2040         return do_wimlib_extract_image(wim, image, target, extract_flags);
2041 }