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   1 /*
   2  * extract_image.c
   3  *
   4  * Support for extracting WIM files.
   5  */
   6
   7 /*
   8  * Copyright (C) 2012, 2013 Eric Biggers
   9  *
  10  * This file is part of wimlib, a library for working with WIM files.
  11  *
  12  * wimlib is free software; you can redistribute it and/or modify it under the
  13  * terms of the GNU General Public License as published by the Free
  14  * Software Foundation; either version 3 of the License, or (at your option)
  15  * any later version.
  16  *
  17  * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY
  18  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
  19  * A PARTICULAR PURPOSE. See the GNU General Public License for more
  20  * details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with wimlib; if not, see http://www.gnu.org/licenses/.
  24  */
  25
  26 #include "config.h"
  27
  28 #include <dirent.h>
  29
  30 #ifdef __WIN32__
  31 #  include "win32.h"
  32 #else
  33 #  ifdef HAVE_UTIME_H
  34 #    include <utime.h>
  35 #  endif
  36 #  include "timestamp.h"
  37 #  include <sys/time.h>
  38 #endif
  39
  40 #include <errno.h>
  41 #include <fcntl.h>
  42 #include <stdlib.h>
  43 #include <string.h>
  44 #include <sys/stat.h>
  45 #include <unistd.h>
  46
  47 #include "dentry.h"
  48 #include "lookup_table.h"
  49 #include "wimlib_internal.h"
  50 #include "xml.h"
  51
  52 #ifdef WITH_NTFS_3G
  53 #  include <ntfs-3g/volume.h>
  54 #endif
  55
  56 #ifdef HAVE_ALLOCA_H
  57 #  include <alloca.h>
  58 #endif
  59
  60
  61 #ifndef __WIN32__
  62
  63 /* Returns the number of components of @path.  */
  64 static unsigned
  65 get_num_path_components(const char *path)
  66 {
  67         unsigned num_components = 0;
  68         while (*path) {
  69                 while (*path == '/')
  70                         path++;
  71                 if (*path)
  72                         num_components++;
  73                 while (*path && *path != '/')
  74                         path++;
  75         }
  76         return num_components;
  77 }
  78
  79 static const char *
  80 path_next_part(const char *path)
  81 {
  82         while (*path && *path != '/')
  83                 path++;
  84         while (*path && *path == '/')
  85                 path++;
  86         return path;
  87 }
  88
  89 static int
  90 extract_regular_file_linked(struct wim_dentry *dentry,
  91                             const char *output_path,
  92                             struct apply_args *args,
  93                             struct wim_lookup_table_entry *lte)
  94 {
  95         /* This mode overrides the normal hard-link extraction and
  96          * instead either symlinks or hardlinks *all* identical files in
  97          * the WIM, even if they are in a different image (in the case
  98          * of a multi-image extraction) */
  99
 100         if (args->extract_flags & WIMLIB_EXTRACT_FLAG_HARDLINK) {
 101                 if (link(lte->extracted_file, output_path) != 0) {
 102                         ERROR_WITH_ERRNO("Failed to hard link "
 103                                          "`%s' to `%s'",
 104                                          output_path, lte->extracted_file);
 105                         return WIMLIB_ERR_LINK;
 106                 }
 107         } else {
 108                 int num_path_components;
 109                 int num_output_dir_path_components;
 110                 size_t extracted_file_len;
 111                 char *p;
 112                 const char *p2;
 113                 size_t i;
 114
 115                 num_path_components = get_num_path_components(dentry->_full_path) - 1;
 116                 num_output_dir_path_components = get_num_path_components(args->target);
 117
 118                 if (args->extract_flags & WIMLIB_EXTRACT_FLAG_MULTI_IMAGE) {
 119                         num_path_components++;
 120                         num_output_dir_path_components--;
 121                 }
 122                 extracted_file_len = strlen(lte->extracted_file);
 123
 124                 char buf[extracted_file_len + 3 * num_path_components + 1];
 125                 p = &buf[0];
 126
 127                 for (i = 0; i < num_path_components; i++) {
 128                         *p++ = '.';
 129                         *p++ = '.';
 130                         *p++ = '/';
 131                 }
 132                 p2 = lte->extracted_file;
 133                 while (*p2 == '/')
 134                         p2++;
 135                 while (num_output_dir_path_components > 0) {
 136                         p2 = path_next_part(p2);
 137                         num_output_dir_path_components--;
 138                 }
 139                 strcpy(p, p2);
 140                 if (symlink(buf, output_path) != 0) {
 141                         ERROR_WITH_ERRNO("Failed to symlink `%s' to `%s'",
 142                                          buf, lte->extracted_file);
 143                         return WIMLIB_ERR_LINK;
 144                 }
 145         }
 146         return 0;
 147 }
 148
 149 static int
 150 symlink_apply_unix_data(const char *link,
 151                         const struct wimlib_unix_data *unix_data)
 152 {
 153         if (lchown(link, unix_data->uid, unix_data->gid)) {
 154                 if (errno == EPERM) {
 155                         /* Ignore */
 156                         WARNING_WITH_ERRNO("failed to set symlink UNIX "
 157                                            "owner/group on \"%s\"", link);
 158                 } else {
 159                         ERROR_WITH_ERRNO("failed to set symlink UNIX "
 160                                          "owner/group on \"%s\"", link);
 161                         return WIMLIB_ERR_INVALID_DENTRY;
 162                 }
 163         }
 164         return 0;
 165 }
 166
 167 static int
 168 fd_apply_unix_data(int fd, const char *path,
 169                    const struct wimlib_unix_data *unix_data)
 170 {
 171         if (fchown(fd, unix_data->uid, unix_data->gid)) {
 172                 if (errno == EPERM) {
 173                         WARNING_WITH_ERRNO("failed to set file UNIX "
 174                                            "owner/group on \"%s\"", path);
 175                         /* Ignore? */
 176                 } else {
 177                         ERROR_WITH_ERRNO("failed to set file UNIX "
 178                                          "owner/group on \"%s\"", path);
 179                         return WIMLIB_ERR_INVALID_DENTRY;
 180                 }
 181         }
 182
 183         if (fchmod(fd, unix_data->mode)) {
 184                 if (errno == EPERM) {
 185                         WARNING_WITH_ERRNO("failed to set UNIX file mode "
 186                                            "on \"%s\"", path);
 187                         /* Ignore? */
 188                 } else {
 189                         ERROR_WITH_ERRNO("failed to set UNIX file mode "
 190                                          "on \"%s\"", path);
 191                         return WIMLIB_ERR_INVALID_DENTRY;
 192                 }
 193         }
 194         return 0;
 195 }
 196
 197 static int
 198 dir_apply_unix_data(const char *dir, const struct wimlib_unix_data *unix_data)
 199 {
 200         int dfd = open(dir, O_RDONLY);
 201         int ret;
 202         if (dfd >= 0) {
 203                 ret = fd_apply_unix_data(dfd, dir, unix_data);
 204                 if (close(dfd)) {
 205                         ERROR_WITH_ERRNO("can't close directory `%s'", dir);
 206                         ret = WIMLIB_ERR_MKDIR;
 207                 }
 208         } else {
 209                 ERROR_WITH_ERRNO("can't open directory `%s'", dir);
 210                 ret = WIMLIB_ERR_MKDIR;
 211         }
 212         return ret;
 213 }
 214
 215 static int
 216 extract_regular_file_unlinked(struct wim_dentry *dentry,
 217                               struct apply_args *args,
 218                               const char *output_path,
 219                               struct wim_lookup_table_entry *lte)
 220 {
 221         /* Normal mode of extraction.  Regular files and hard links are
 222          * extracted in the way that they appear in the WIM. */
 223
 224         int out_fd;
 225         int ret;
 226         struct wim_inode *inode = dentry->d_inode;
 227
 228         if (!((args->extract_flags & WIMLIB_EXTRACT_FLAG_MULTI_IMAGE)
 229                 && (args->extract_flags & (WIMLIB_EXTRACT_FLAG_SYMLINK |
 230                                      WIMLIB_EXTRACT_FLAG_HARDLINK))))
 231         {
 232                 /* If the dentry is part of a hard link set of at least 2
 233                  * dentries and one of the other dentries has already been
 234                  * extracted, make a hard link to the file corresponding to this
 235                  * already-extracted directory.  Otherwise, extract the file and
 236                  * set the inode->i_extracted_file field so that other dentries
 237                  * in the hard link group can link to it. */
 238                 if (inode->i_nlink > 1) {
 239                         if (inode->i_extracted_file) {
 240                                 DEBUG("Extracting hard link `%s' => `%s'",
 241                                       output_path, inode->i_extracted_file);
 242                                 if (link(inode->i_extracted_file, output_path) != 0) {
 243                                         ERROR_WITH_ERRNO("Failed to hard link "
 244                                                          "`%s' to `%s'",
 245                                                          output_path,
 246                                                          inode->i_extracted_file);
 247                                         return WIMLIB_ERR_LINK;
 248                                 }
 249                                 return 0;
 250                         }
 251                         FREE(inode->i_extracted_file);
 252                         inode->i_extracted_file = STRDUP(output_path);
 253                         if (!inode->i_extracted_file) {
 254                                 ERROR("Failed to allocate memory for filename");
 255                                 return WIMLIB_ERR_NOMEM;
 256                         }
 257                 }
 258         }
 259
 260         /* Extract the contents of the file to @output_path. */
 261
 262         out_fd = open(output_path, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 263         if (out_fd == -1) {
 264                 ERROR_WITH_ERRNO("Failed to open the file `%s' for writing",
 265                                  output_path);
 266                 return WIMLIB_ERR_OPEN;
 267         }
 268
 269         if (!lte) {
 270                 /* Empty file with no lookup table entry */
 271                 DEBUG("Empty file `%s'.", output_path);
 272                 ret = 0;
 273                 goto out_extract_unix_data;
 274         }
 275
 276         ret = extract_wim_resource_to_fd(lte, out_fd, wim_resource_size(lte));
 277         if (ret) {
 278                 ERROR("Failed to extract resource to `%s'", output_path);
 279                 goto out;
 280         }
 281
 282 out_extract_unix_data:
 283         if (args->extract_flags & WIMLIB_EXTRACT_FLAG_UNIX_DATA) {
 284                 struct wimlib_unix_data unix_data;
 285                 ret = inode_get_unix_data(inode, &unix_data, NULL);
 286                 if (ret > 0)
 287                         ;
 288                 else if (ret < 0)
 289                         ret = 0;
 290                 else
 291                         ret = fd_apply_unix_data(out_fd, output_path, &unix_data);
 292                 if (ret)
 293                         goto out;
 294         }
 295         if (lte)
 296                 args->progress.extract.completed_bytes += wim_resource_size(lte);
 297 out:
 298         if (close(out_fd) != 0) {
 299                 ERROR_WITH_ERRNO("Failed to close file `%s'", output_path);
 300                 if (ret == 0)
 301                         ret = WIMLIB_ERR_WRITE;
 302         }
 303         return ret;
 304 }
 305
 306 static int
 307 extract_regular_file(struct wim_dentry *dentry,
 308                      struct apply_args *args,
 309                      const char *output_path)
 310 {
 311         struct wim_lookup_table_entry *lte;
 312         const struct wim_inode *inode = dentry->d_inode;
 313
 314         lte = inode_unnamed_lte_resolved(inode);
 315
 316         if (lte && (args->extract_flags & (WIMLIB_EXTRACT_FLAG_SYMLINK |
 317                                            WIMLIB_EXTRACT_FLAG_HARDLINK)))
 318         {
 319                 if (lte->extracted_file) {
 320                         return extract_regular_file_linked(dentry, output_path, args, lte);
 321                 } else {
 322                         lte->extracted_file = STRDUP(output_path);
 323                         if (!lte->extracted_file)
 324                                 return WIMLIB_ERR_NOMEM;
 325                 }
 326         }
 327         return extract_regular_file_unlinked(dentry, args, output_path, lte);
 328 }
 329
 330 static int
 331 extract_symlink(struct wim_dentry *dentry,
 332                 struct apply_args *args,
 333                 const char *output_path)
 334 {
 335         char target[4096 + args->target_realpath_len];
 336         char *fixed_target;
 337         const struct wim_inode *inode = dentry->d_inode;
 338
 339         ssize_t ret = wim_inode_readlink(inode,
 340                                          target + args->target_realpath_len,
 341                                          sizeof(target) - args->target_realpath_len - 1);
 342         struct wim_lookup_table_entry *lte;
 343
 344         if (ret <= 0) {
 345                 ERROR("Could not read the symbolic link from dentry `%s'",
 346                       dentry->_full_path);
 347                 return WIMLIB_ERR_INVALID_DENTRY;
 348         }
 349         target[args->target_realpath_len + ret] = '\0';
 350         if (target[args->target_realpath_len] == '/' &&
 351             args->extract_flags & WIMLIB_EXTRACT_FLAG_RPFIX)
 352         {
 353                 /* Fix absolute symbolic link target to point into the actual
 354                  * extraction destination */
 355                 memcpy(target, args->target_realpath,
 356                        args->target_realpath_len);
 357                 fixed_target = target;
 358         } else {
 359                 /* Keep same link target */
 360                 fixed_target = target + args->target_realpath_len;
 361         }
 362         ret = symlink(fixed_target, output_path);
 363         if (ret) {
 364                 ERROR_WITH_ERRNO("Failed to symlink `%s' to `%s'",
 365                                  output_path, fixed_target);
 366                 return WIMLIB_ERR_LINK;
 367         }
 368         if (args->extract_flags & WIMLIB_EXTRACT_FLAG_UNIX_DATA) {
 369                 struct wimlib_unix_data unix_data;
 370                 ret = inode_get_unix_data(inode, &unix_data, NULL);
 371                 if (ret > 0)
 372                         ;
 373                 else if (ret < 0)
 374                         ret = 0;
 375                 else
 376                         ret = symlink_apply_unix_data(output_path, &unix_data);
 377                 if (ret)
 378                         return ret;
 379         }
 380         lte = inode_unnamed_lte_resolved(inode);
 381         wimlib_assert(lte != NULL);
 382         args->progress.extract.completed_bytes += wim_resource_size(lte);
 383         return 0;
 384 }
 385
 386 #endif /* !__WIN32__ */
 387
 388 static int
 389 extract_directory(struct wim_dentry *dentry,
 390                   const tchar *output_path, bool is_root)
 391 {
 392         int ret;
 393         struct stat stbuf;
 394
 395         ret = tstat(output_path, &stbuf);
 396         if (ret == 0) {
 397                 if (S_ISDIR(stbuf.st_mode)) {
 398                         /*if (!is_root)*/
 399                                 /*WARNING("`%s' already exists", output_path);*/
 400                         goto dir_exists;
 401                 } else {
 402                         ERROR("`%"TS"' is not a directory", output_path);
 403                         return WIMLIB_ERR_MKDIR;
 404                 }
 405         } else {
 406                 if (errno != ENOENT) {
 407                         ERROR_WITH_ERRNO("Failed to stat `%"TS"'", output_path);
 408                         return WIMLIB_ERR_STAT;
 409                 }
 410         }
 411
 412         if (tmkdir(output_path, S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH))
 413         {
 414                 ERROR_WITH_ERRNO("Cannot create directory `%"TS"'", output_path);
 415                 return WIMLIB_ERR_MKDIR;
 416         }
 417 dir_exists:
 418         ret = 0;
 419 #ifndef __WIN32__
 420         if (dentry) {
 421                 struct wimlib_unix_data unix_data;
 422                 ret = inode_get_unix_data(dentry->d_inode, &unix_data, NULL);
 423                 if (ret > 0)
 424                         ;
 425                 else if (ret < 0)
 426                         ret = 0;
 427                 else
 428                         ret = dir_apply_unix_data(output_path, &unix_data);
 429         }
 430 #endif
 431         return ret;
 432 }
 433
 434 #ifndef __WIN32__
 435 static int
 436 unix_do_apply_dentry(const char *output_path, size_t output_path_len,
 437                      struct wim_dentry *dentry, struct apply_args *args)
 438 {
 439         const struct wim_inode *inode = dentry->d_inode;
 440
 441         if (inode_is_symlink(inode))
 442                 return extract_symlink(dentry, args, output_path);
 443         else if (inode_is_directory(inode))
 444                 return extract_directory((args->extract_flags &
 445                                            WIMLIB_EXTRACT_FLAG_UNIX_DATA) ? dentry : NULL,
 446                                          output_path, false);
 447         else
 448                 return extract_regular_file(dentry, args, output_path);
 449 }
 450
 451 static int
 452 unix_do_apply_dentry_timestamps(const char *output_path,
 453                                 size_t output_path_len,
 454                                 struct wim_dentry *dentry,
 455                                 struct apply_args *args)
 456 {
 457         int ret;
 458         const struct wim_inode *inode = dentry->d_inode;
 459
 460 #ifdef HAVE_UTIMENSAT
 461         /* Convert the WIM timestamps, which are accurate to 100 nanoseconds,
 462          * into `struct timespec's for passing to utimensat(), which is accurate
 463          * to 1 nanosecond. */
 464
 465         struct timespec ts[2];
 466         ts[0] = wim_timestamp_to_timespec(inode->i_last_access_time);
 467         ts[1] = wim_timestamp_to_timespec(inode->i_last_write_time);
 468         ret = utimensat(AT_FDCWD, output_path, ts, AT_SYMLINK_NOFOLLOW);
 469         if (ret)
 470                 ret = errno;
 471 #else
 472         ret = ENOSYS;
 473 #endif
 474
 475         if (ret == ENOSYS) {
 476                 /* utimensat() not implemented or not available */
 477         #ifdef HAVE_LUTIMES
 478                 /* Convert the WIM timestamps, which are accurate to 100
 479                  * nanoseconds, into `struct timeval's for passing to lutimes(),
 480                  * which is accurate to 1 microsecond. */
 481                 struct timeval tv[2];
 482                 tv[0] = wim_timestamp_to_timeval(inode->i_last_access_time);
 483                 tv[1] = wim_timestamp_to_timeval(inode->i_last_write_time);
 484                 ret = lutimes(output_path, tv);
 485                 if (ret)
 486                         ret = errno;
 487         #endif
 488         }
 489
 490         if (ret == ENOSYS) {
 491                 /* utimensat() and lutimes() both not implemented or not
 492                  * available */
 493         #ifdef HAVE_UTIME
 494                 /* Convert the WIM timestamps, which are accurate to 100
 495                  * nanoseconds, into a `struct utimbuf's for passing to
 496                  * utime(), which is accurate to 1 second. */
 497                 struct utimbuf buf;
 498                 buf.actime = wim_timestamp_to_unix(inode->i_last_access_time);
 499                 buf.modtime = wim_timestamp_to_unix(inode->i_last_write_time);
 500                 ret = utime(output_path, &buf);
 501         #endif
 502         }
 503         if (ret && args->num_utime_warnings < 10) {
 504                 WARNING_WITH_ERRNO("Failed to set timestamp on file `%s'",
 505                                     output_path);
 506                 args->num_utime_warnings++;
 507         }
 508         return 0;
 509 }
 510 #endif /* !__WIN32__ */
 511
 512 static int
 513 do_apply_op(struct wim_dentry *dentry, struct apply_args *args,
 514             int (*apply_dentry_func)(const tchar *, size_t,
 515                                      struct wim_dentry *, struct apply_args *))
 516 {
 517         tchar *p;
 518         const tchar *full_path;
 519         size_t full_path_nchars;
 520
 521         wimlib_assert(dentry->_full_path != NULL);
 522         full_path = dentry->_full_path + 1;
 523         full_path_nchars = dentry->full_path_nbytes / sizeof(tchar) - 1;
 524         tchar output_path[args->target_nchars + 1 +
 525                          (full_path_nchars - args->wim_source_path_nchars) + 1];
 526         p = output_path;
 527
 528         /*print_dentry(dentry, NULL);*/
 529         /*ERROR("%"TS" %"TS, args->target, dentry->_full_path);*/
 530         /*ERROR("");*/
 531
 532         tmemcpy(p, args->target, args->target_nchars);
 533         p += args->target_nchars;
 534
 535         if (dentry != args->extract_root) {
 536                 *p++ = T('/');
 537                 tmemcpy(p, full_path + args->wim_source_path_nchars,
 538                         full_path_nchars - args->wim_source_path_nchars);
 539                 p += full_path_nchars - args->wim_source_path_nchars;
 540         }
 541         *p = T('\0');
 542         return (*apply_dentry_func)(output_path, p - output_path,
 543                                     dentry, args);
 544 }
 545
 546
 547 /* Extracts a file, directory, or symbolic link from the WIM archive. */
 548 static int
 549 apply_dentry_normal(struct wim_dentry *dentry, void *arg)
 550 {
 551 #ifdef __WIN32__
 552         return do_apply_op(dentry, arg, win32_do_apply_dentry);
 553 #else
 554         return do_apply_op(dentry, arg, unix_do_apply_dentry);
 555 #endif
 556 }
 557
 558
 559 /* Apply timestamps to an extracted file or directory */
 560 static int
 561 apply_dentry_timestamps_normal(struct wim_dentry *dentry, void *arg)
 562 {
 563 #ifdef __WIN32__
 564         return do_apply_op(dentry, arg, win32_do_apply_dentry_timestamps);
 565 #else
 566         return do_apply_op(dentry, arg, unix_do_apply_dentry_timestamps);
 567 #endif
 568 }
 569
 570 static bool
 571 dentry_is_descendent(const struct wim_dentry *dentry,
 572                      const struct wim_dentry *ancestor)
 573 {
 574         for (;;) {
 575                 if (dentry == ancestor)
 576                         return true;
 577                 if (dentry_is_root(dentry))
 578                         return false;
 579                 dentry = dentry->parent;
 580         }
 581 }
 582
 583 /* Extract a dentry if it hasn't already been extracted and either
 584  * WIMLIB_EXTRACT_FLAG_NO_STREAMS is not specified, or the dentry is a directory
 585  * and/or has no unnamed stream. */
 586 static int
 587 maybe_apply_dentry(struct wim_dentry *dentry, void *arg)
 588 {
 589         struct apply_args *args = arg;
 590         int ret;
 591
 592         if (dentry->is_extracted)
 593                 return 0;
 594
 595         if (!dentry_is_descendent(dentry, args->extract_root))
 596                 return 0;
 597
 598         if (args->extract_flags & WIMLIB_EXTRACT_FLAG_NO_STREAMS &&
 599             !dentry_is_directory(dentry) &&
 600             inode_unnamed_lte_resolved(dentry->d_inode) != NULL)
 601                 return 0;
 602
 603         if ((args->extract_flags & WIMLIB_EXTRACT_FLAG_VERBOSE) &&
 604              args->progress_func) {
 605                 args->progress.extract.cur_path = dentry->_full_path;
 606                 args->progress_func(WIMLIB_PROGRESS_MSG_EXTRACT_DENTRY,
 607                                     &args->progress);
 608         }
 609         ret = args->apply_dentry(dentry, args);
 610         if (ret == 0)
 611                 dentry->is_extracted = 1;
 612         return ret;
 613 }
 614
 615 static void
 616 calculate_bytes_to_extract(struct list_head *stream_list,
 617                            int extract_flags,
 618                            union wimlib_progress_info *progress)
 619 {
 620         struct wim_lookup_table_entry *lte;
 621         u64 total_bytes = 0;
 622         u64 num_streams = 0;
 623
 624         /* For each stream to be extracted... */
 625         list_for_each_entry(lte, stream_list, extraction_list) {
 626                 if (extract_flags &
 627                     (WIMLIB_EXTRACT_FLAG_SYMLINK | WIMLIB_EXTRACT_FLAG_HARDLINK))
 628                 {
 629                         /* In the symlink or hard link extraction mode, each
 630                          * stream will be extracted one time regardless of how
 631                          * many dentries share the stream. */
 632                         wimlib_assert(!(extract_flags & WIMLIB_EXTRACT_FLAG_NTFS));
 633                         if (!lte->extracted_file) {
 634                                 num_streams++;
 635                                 total_bytes += wim_resource_size(lte);
 636                         }
 637                 } else {
 638                         num_streams += lte->out_refcnt;
 639                         total_bytes += lte->out_refcnt * wim_resource_size(lte);
 640                 }
 641         }
 642         progress->extract.num_streams = num_streams;
 643         progress->extract.total_bytes = total_bytes;
 644         progress->extract.completed_bytes = 0;
 645 }
 646
 647 static void
 648 maybe_add_stream_for_extraction(struct wim_lookup_table_entry *lte,
 649                                 struct list_head *stream_list)
 650 {
 651         if (++lte->out_refcnt == 1) {
 652                 INIT_LIST_HEAD(&lte->inode_list);
 653                 list_add_tail(&lte->extraction_list, stream_list);
 654         }
 655 }
 656
 657 static void
 658 inode_find_streams_for_extraction(struct wim_inode *inode,
 659                                   struct list_head *stream_list,
 660                                   int extract_flags)
 661 {
 662         struct wim_lookup_table_entry *lte;
 663         bool inode_added = false;
 664
 665         lte = inode_unnamed_lte_resolved(inode);
 666         if (lte) {
 667                 maybe_add_stream_for_extraction(lte, stream_list);
 668                 list_add_tail(&inode->i_lte_inode_list, &lte->inode_list);
 669                 inode_added = true;
 670         }
 671
 672         /* Determine whether to include alternate data stream entries or not.
 673          *
 674          * UNIX:  Include them if extracting using NTFS-3g.
 675          *
 676          * Windows: Include them undconditionally, although if the filesystem is
 677          * not NTFS we won't actually be able to extract them. */
 678 #if defined(WITH_NTFS_3G)
 679         if (extract_flags & WIMLIB_EXTRACT_FLAG_NTFS)
 680 #elif defined(__WIN32__)
 681         if (1)
 682 #else
 683         if (0)
 684 #endif
 685         {
 686                 for (unsigned i = 0; i < inode->i_num_ads; i++) {
 687                         if (inode->i_ads_entries[i].stream_name_nbytes != 0) {
 688                                 lte = inode->i_ads_entries[i].lte;
 689                                 if (lte) {
 690                                         maybe_add_stream_for_extraction(lte,
 691                                                                         stream_list);
 692                                         if (!inode_added) {
 693                                                 list_add_tail(&inode->i_lte_inode_list,
 694                                                               &lte->inode_list);
 695                                                 inode_added = true;
 696                                         }
 697                                 }
 698                         }
 699                 }
 700         }
 701 }
 702
 703 struct find_streams_ctx {
 704         struct list_head stream_list;
 705         int extract_flags;
 706 };
 707
 708 static int
 709 dentry_find_streams_to_extract(struct wim_dentry *dentry, void *_ctx)
 710 {
 711         struct find_streams_ctx *ctx = _ctx;
 712         struct wim_inode *inode = dentry->d_inode;
 713
 714         dentry->is_extracted = 0;
 715         if (!inode->i_visited) {
 716                 inode_find_streams_for_extraction(inode, &ctx->stream_list,
 717                                                   ctx->extract_flags);
 718                 inode->i_visited = 1;
 719         }
 720         return 0;
 721 }
 722
 723 static int
 724 dentry_resolve_and_zero_lte_refcnt(struct wim_dentry *dentry, void *_lookup_table)
 725 {
 726         struct wim_inode *inode = dentry->d_inode;
 727         struct wim_lookup_table *lookup_table = _lookup_table;
 728         struct wim_lookup_table_entry *lte;
 729
 730         inode_resolve_ltes(inode, lookup_table);
 731         for (unsigned i = 0; i <= inode->i_num_ads; i++) {
 732                 lte = inode_stream_lte_resolved(inode, i);
 733                 if (lte)
 734                         lte->out_refcnt = 0;
 735         }
 736         return 0;
 737 }
 738
 739 static void
 740 find_streams_for_extraction(struct wim_dentry *root,
 741                             struct list_head *stream_list,
 742                             struct wim_lookup_table *lookup_table,
 743                             int extract_flags)
 744 {
 745         struct find_streams_ctx ctx;
 746
 747         INIT_LIST_HEAD(&ctx.stream_list);
 748         ctx.extract_flags = extract_flags;
 749         for_dentry_in_tree(root, dentry_resolve_and_zero_lte_refcnt, lookup_table);
 750         for_dentry_in_tree(root, dentry_find_streams_to_extract, &ctx);
 751         list_transfer(&ctx.stream_list, stream_list);
 752 }
 753
 754 static int
 755 dentry_mark_inode_unvisited(struct wim_dentry *dentry, void *_ignore)
 756 {
 757         dentry->d_inode->i_visited = 0;
 758         return 0;
 759 }
 760
 761 struct apply_operations {
 762         int (*apply_dentry)(struct wim_dentry *dentry, void *arg);
 763         int (*apply_dentry_timestamps)(struct wim_dentry *dentry, void *arg);
 764 };
 765
 766 static const struct apply_operations normal_apply_operations = {
 767         .apply_dentry = apply_dentry_normal,
 768         .apply_dentry_timestamps = apply_dentry_timestamps_normal,
 769 };
 770
 771 #ifdef WITH_NTFS_3G
 772 static const struct apply_operations ntfs_apply_operations = {
 773         .apply_dentry = apply_dentry_ntfs,
 774         .apply_dentry_timestamps = apply_dentry_timestamps_ntfs,
 775 };
 776 #endif
 777
 778 static int
 779 apply_stream_list(struct list_head *stream_list,
 780                   struct apply_args *args,
 781                   const struct apply_operations *ops,
 782                   wimlib_progress_func_t progress_func)
 783 {
 784         uint64_t bytes_per_progress = args->progress.extract.total_bytes / 100;
 785         uint64_t next_progress = bytes_per_progress;
 786         struct wim_lookup_table_entry *lte;
 787         struct wim_inode *inode;
 788         struct wim_dentry *dentry;
 789         int ret;
 790
 791         /* This complicated loop is essentially looping through the dentries,
 792          * although dentries may be visited more than once (if a dentry contains
 793          * two different nonempty streams) or not at all (if a dentry contains
 794          * no non-empty streams).
 795          *
 796          * The outer loop is over the distinct streams to be extracted so that
 797          * sequential reading of the WIM can be implemented. */
 798
 799         /* For each distinct stream to be extracted */
 800         list_for_each_entry(lte, stream_list, extraction_list) {
 801                 /* For each inode that contains the stream */
 802                 list_for_each_entry(inode, &lte->inode_list, i_lte_inode_list) {
 803                         /* For each dentry that points to the inode */
 804                         inode_for_each_dentry(dentry, inode) {
 805                                 /* Extract the dentry if it was not already
 806                                  * extracted */
 807                                 ret = maybe_apply_dentry(dentry, args);
 808                                 if (ret)
 809                                         return ret;
 810                                 if (progress_func &&
 811                                     args->progress.extract.completed_bytes >= next_progress)
 812                                 {
 813                                         progress_func(WIMLIB_PROGRESS_MSG_EXTRACT_STREAMS,
 814                                                       &args->progress);
 815                                         if (args->progress.extract.completed_bytes >=
 816                                             args->progress.extract.total_bytes)
 817                                         {
 818                                                 next_progress = ~0ULL;
 819                                         } else {
 820                                                 next_progress =
 821                                                         min (args->progress.extract.completed_bytes +
 822                                                              bytes_per_progress,
 823                                                              args->progress.extract.total_bytes);
 824                                         }
 825                                 }
 826                         }
 827                 }
 828         }
 829         return 0;
 830 }
 831
 832 static int
 833 sort_stream_list_by_wim_position(struct list_head *stream_list)
 834 {
 835         struct list_head *cur;
 836         size_t num_streams;
 837         struct wim_lookup_table_entry **array;
 838         size_t i;
 839         size_t array_size;
 840
 841         num_streams = 0;
 842         list_for_each(cur, stream_list)
 843                 num_streams++;
 844         array_size = num_streams * sizeof(array[0]);
 845         array = MALLOC(array_size);
 846         if (!array) {
 847                 ERROR("Failed to allocate %zu bytes to sort stream entries",
 848                       array_size);
 849                 return WIMLIB_ERR_NOMEM;
 850         }
 851         cur = stream_list->next;
 852         for (i = 0; i < num_streams; i++) {
 853                 array[i] = container_of(cur, struct wim_lookup_table_entry, extraction_list);
 854                 cur = cur->next;
 855         }
 856
 857         qsort(array, num_streams, sizeof(array[0]), cmp_streams_by_wim_position);
 858
 859         INIT_LIST_HEAD(stream_list);
 860         for (i = 0; i < num_streams; i++)
 861                 list_add_tail(&array[i]->extraction_list, stream_list);
 862         FREE(array);
 863         return 0;
 864 }
 865
 866 /*
 867  * extract_tree - Extract a file or directory tree from the currently selected
 868  *                WIM image.
 869  *
 870  * @wim:        WIMStruct for the WIM file, with the desired image selected
 871  *              (as wim->current_image).
 872  * @wim_source_path:
 873  *              "Canonical" (i.e. no leading or trailing slashes, path
 874  *              separators forwald slashes) path inside the WIM image to
 875  *              extract.  An empty string means the full image.
 876  * @target:
 877  *              Filesystem path to extract the file or directory tree to.
 878  *
 879  * @extract_flags:
 880  *              WIMLIB_EXTRACT_FLAG_*.  Also, the private flag
 881  *              WIMLIB_EXTRACT_FLAG_MULTI_IMAGE will be set if this is being
 882  *              called through wimlib_extract_image() with WIMLIB_ALL_IMAGES as
 883  *              the image.
 884  *
 885  * @progress_func:
 886  *              If non-NULL, progress function for the extraction.  The messages
 887  *              we may in this function are:
 888  *
 889  *              WIMLIB_PROGRESS_MSG_EXTRACT_TREE_BEGIN or
 890  *                      WIMLIB_PROGRESS_MSG_EXTRACT_IMAGE_BEGIN;
 891  *              WIMLIB_PROGRESS_MSG_EXTRACT_DIR_STRUCTURE_BEGIN;
 892  *              WIMLIB_PROGRESS_MSG_EXTRACT_DIR_STRUCTURE_END;
 893  *              WIMLIB_PROGRESS_MSG_EXTRACT_DENTRY;
 894  *              WIMLIB_PROGRESS_MSG_EXTRACT_STREAMS;
 895  *              WIMLIB_PROGRESS_MSG_APPLY_TIMESTAMPS;
 896  *              WIMLIB_PROGRESS_MSG_EXTRACT_TREE_END or
 897  *                      WIMLIB_PROGRESS_MSG_EXTRACT_IMAGE_END.
 898  *
 899  * Returns 0 on success; nonzero on failure.
 900  */
 901 static int
 902 extract_tree(WIMStruct *wim, const tchar *wim_source_path, const tchar *target,
 903              int extract_flags, wimlib_progress_func_t progress_func)
 904 {
 905         int ret;
 906         struct list_head stream_list;
 907         struct apply_args args;
 908         const struct apply_operations *ops;
 909         struct wim_dentry *root;
 910
 911         memset(&args, 0, sizeof(args));
 912
 913         args.w                      = wim;
 914         args.target                 = target;
 915         args.extract_flags          = extract_flags;
 916         args.progress_func          = progress_func;
 917         args.target_nchars          = tstrlen(target);
 918         args.wim_source_path_nchars = tstrlen(wim_source_path);
 919
 920         if (progress_func) {
 921                 args.progress.extract.wimfile_name = wim->filename;
 922                 args.progress.extract.image = wim->current_image;
 923                 args.progress.extract.extract_flags = (extract_flags &
 924                                                        WIMLIB_EXTRACT_MASK_PUBLIC);
 925                 args.progress.extract.image_name = wimlib_get_image_name(wim,
 926                                                                          wim->current_image);
 927                 args.progress.extract.extract_root_wim_source_path = wim_source_path;
 928                 args.progress.extract.target = target;
 929         }
 930
 931 #ifdef WITH_NTFS_3G
 932         if (extract_flags & WIMLIB_EXTRACT_FLAG_NTFS) {
 933                 args.vol = ntfs_mount(target, 0);
 934                 if (!args.vol) {
 935                         ERROR_WITH_ERRNO("Failed to mount NTFS volume `%"TS"'",
 936                                          target);
 937                         ret = WIMLIB_ERR_NTFS_3G;
 938                         goto out;
 939                 }
 940                 ops = &ntfs_apply_operations;
 941         } else
 942 #endif
 943                 ops = &normal_apply_operations;
 944
 945         root = get_dentry(wim, wim_source_path);
 946         if (!root) {
 947                 ERROR("Path \"%"TS"\" does not exist in WIM image %d",
 948                       wim_source_path, wim->current_image);
 949                 ret = WIMLIB_ERR_PATH_DOES_NOT_EXIST;
 950                 goto out_ntfs_umount;
 951         }
 952         args.extract_root = root;
 953
 954         /* Build a list of the streams that need to be extracted */
 955         find_streams_for_extraction(root,
 956                                     &stream_list,
 957                                     wim->lookup_table, extract_flags);
 958
 959         /* Calculate the number of bytes of data that will be extracted */
 960         calculate_bytes_to_extract(&stream_list, extract_flags,
 961                                    &args.progress);
 962
 963         if (progress_func) {
 964                 progress_func(*wim_source_path ? WIMLIB_PROGRESS_MSG_EXTRACT_TREE_BEGIN :
 965                               WIMLIB_PROGRESS_MSG_EXTRACT_IMAGE_BEGIN,
 966                               &args.progress);
 967         }
 968
 969         /* If a sequential extraction was specified, sort the streams to be
 970          * extracted by their position in the WIM file, so that the WIM file can
 971          * be read sequentially. */
 972         if (extract_flags & WIMLIB_EXTRACT_FLAG_SEQUENTIAL) {
 973                 ret = sort_stream_list_by_wim_position(&stream_list);
 974                 if (ret != 0) {
 975                         WARNING("Falling back to non-sequential extraction");
 976                         extract_flags &= ~WIMLIB_EXTRACT_FLAG_SEQUENTIAL;
 977                 }
 978         }
 979
 980         if (progress_func) {
 981                 progress_func(WIMLIB_PROGRESS_MSG_EXTRACT_DIR_STRUCTURE_BEGIN,
 982                               &args.progress);
 983         }
 984
 985         ret = calculate_dentry_tree_full_paths(root);
 986         if (ret)
 987                 goto out_mark_inodes_unvisited;
 988
 989         /* Make the directory structure and extract empty files */
 990         args.extract_flags |= WIMLIB_EXTRACT_FLAG_NO_STREAMS;
 991         args.apply_dentry = ops->apply_dentry;
 992         ret = for_dentry_in_tree(root, maybe_apply_dentry, &args);
 993         args.extract_flags &= ~WIMLIB_EXTRACT_FLAG_NO_STREAMS;
 994         if (ret)
 995                 goto out_mark_inodes_unvisited;
 996
 997         if (progress_func) {
 998                 progress_func(WIMLIB_PROGRESS_MSG_EXTRACT_DIR_STRUCTURE_END,
 999                               &args.progress);
1000         }
1001
1002         if (extract_flags & WIMLIB_EXTRACT_FLAG_RPFIX) {
1003                 args.target_realpath = realpath(target, NULL);
1004                 if (!args.target_realpath) {
1005                         ret = WIMLIB_ERR_NOMEM;
1006                         goto out_mark_inodes_unvisited;
1007                 }
1008                 args.target_realpath_len = tstrlen(args.target_realpath);
1009         }
1010
1011         /* Extract non-empty files */
1012         ret = apply_stream_list(&stream_list, &args, ops, progress_func);
1013         if (ret)
1014                 goto out_free_target_realpath;
1015
1016         if (progress_func) {
1017                 progress_func(WIMLIB_PROGRESS_MSG_APPLY_TIMESTAMPS,
1018                               &args.progress);
1019         }
1020
1021         /* Apply timestamps */
1022         ret = for_dentry_in_tree_depth(root,
1023                                        ops->apply_dentry_timestamps, &args);
1024         if (ret)
1025                 goto out_free_target_realpath;
1026
1027         if (progress_func) {
1028                 progress_func(*wim_source_path ? WIMLIB_PROGRESS_MSG_EXTRACT_TREE_END :
1029                               WIMLIB_PROGRESS_MSG_EXTRACT_IMAGE_END,
1030                               &args.progress);
1031         }
1032 out_free_target_realpath:
1033         FREE(args.target_realpath);
1034 out_mark_inodes_unvisited:
1035         for_dentry_in_tree(root, dentry_mark_inode_unvisited, NULL);
1036 out_ntfs_umount:
1037 #ifdef WITH_NTFS_3G
1038         /* Unmount the NTFS volume */
1039         if (extract_flags & WIMLIB_EXTRACT_FLAG_NTFS) {
1040                 if (ntfs_umount(args.vol, FALSE) != 0) {
1041                         ERROR_WITH_ERRNO("Failed to unmount NTFS volume `%"TS"'",
1042                                          args.target);
1043                         if (ret == 0)
1044                                 ret = WIMLIB_ERR_NTFS_3G;
1045                 }
1046         }
1047 #endif
1048 out:
1049         return ret;
1050 }
1051
1052 /* Validates a single wimlib_extract_command, mostly checking to make sure the
1053  * extract flags make sense. */
1054 static int
1055 check_extract_command(struct wimlib_extract_command *cmd, int wim_header_flags)
1056 {
1057         int extract_flags;
1058         bool is_entire_image = (cmd->wim_source_path[0] == T('\0'));
1059
1060         /* Empty destination path? */
1061         if (cmd->fs_dest_path[0] == T('\0'))
1062                 return WIMLIB_ERR_INVALID_PARAM;
1063
1064         extract_flags = cmd->extract_flags;
1065
1066         /* Specified both symlink and hardlink modes? */
1067         if ((extract_flags &
1068              (WIMLIB_EXTRACT_FLAG_SYMLINK |
1069               WIMLIB_EXTRACT_FLAG_HARDLINK)) == (WIMLIB_EXTRACT_FLAG_SYMLINK |
1070                                                  WIMLIB_EXTRACT_FLAG_HARDLINK))
1071                 return WIMLIB_ERR_INVALID_PARAM;
1072
1073 #ifdef __WIN32__
1074         /* Wanted UNIX data on Win32? */
1075         if (extract_flags & WIMLIB_EXTRACT_FLAG_UNIX_DATA) {
1076                 ERROR("Extracting UNIX data is not supported on Windows");
1077                 return WIMLIB_ERR_INVALID_PARAM;
1078         }
1079         /* Wanted linked extraction on Windows?  (XXX This is possible, just not
1080          * implemented yet.) */
1081         if (extract_flags & (WIMLIB_EXTRACT_FLAG_SYMLINK |
1082                              WIMLIB_EXTRACT_FLAG_HARDLINK))
1083         {
1084                 ERROR("Linked extraction modes are not supported on Windows");
1085                 return WIMLIB_ERR_INVALID_PARAM;
1086         }
1087 #endif
1088
1089         if (extract_flags & WIMLIB_EXTRACT_FLAG_NTFS) {
1090                 /* NTFS-3g extraction mode requested */
1091 #ifdef WITH_NTFS_3G
1092                 if ((extract_flags & (WIMLIB_EXTRACT_FLAG_SYMLINK |
1093                                       WIMLIB_EXTRACT_FLAG_HARDLINK))) {
1094                         ERROR("Cannot specify symlink or hardlink flags when applying\n"
1095                               "        directly to a NTFS volume");
1096                         return WIMLIB_ERR_INVALID_PARAM;
1097                 }
1098                 if (!is_entire_image &&
1099                     (extract_flags & WIMLIB_EXTRACT_FLAG_NTFS))
1100                 {
1101                         ERROR("When applying directly to a NTFS volume you can "
1102                               "only extract a full image, not part of one");
1103                         return WIMLIB_ERR_INVALID_PARAM;
1104                 }
1105                 if (extract_flags & WIMLIB_EXTRACT_FLAG_UNIX_DATA) {
1106                         ERROR("Cannot restore UNIX-specific data in "
1107                               "the NTFS extraction mode");
1108                         return WIMLIB_ERR_INVALID_PARAM;
1109                 }
1110 #else
1111                 ERROR("wimlib was compiled without support for NTFS-3g, so");
1112                 ERROR("we cannot apply a WIM image directly to a NTFS volume");
1113                 return WIMLIB_ERR_UNSUPPORTED;
1114 #endif
1115         }
1116
1117         if ((extract_flags & (WIMLIB_EXTRACT_FLAG_RPFIX |
1118                               WIMLIB_EXTRACT_FLAG_NORPFIX)) ==
1119                 (WIMLIB_EXTRACT_FLAG_RPFIX | WIMLIB_EXTRACT_FLAG_NORPFIX))
1120         {
1121                 ERROR("Cannot specify RPFIX and NORPFIX flags at the same time!");
1122                 return WIMLIB_ERR_INVALID_PARAM;
1123         }
1124
1125         if ((extract_flags & (WIMLIB_EXTRACT_FLAG_RPFIX |
1126                               WIMLIB_EXTRACT_FLAG_NORPFIX)) == 0)
1127         {
1128                 /* Do reparse point fixups by default if the WIM header says
1129                  * they are enabled and we are extracting a full image. */
1130                 if ((wim_header_flags & WIM_HDR_FLAG_RP_FIX) && is_entire_image)
1131                         extract_flags |= WIMLIB_EXTRACT_FLAG_RPFIX;
1132         }
1133
1134         if (!is_entire_image && (extract_flags & WIMLIB_EXTRACT_FLAG_RPFIX)) {
1135                 ERROR("Cannot specify --rpfix when not extracting entire image");
1136                 return WIMLIB_ERR_INVALID_PARAM;
1137         }
1138
1139         cmd->extract_flags = extract_flags;
1140         return 0;
1141 }
1142
1143
1144 /* Internal function to execute extraction commands for a WIM image. */
1145 static int
1146 do_wimlib_extract_files(WIMStruct *wim,
1147                         int image,
1148                         struct wimlib_extract_command *cmds,
1149                         size_t num_cmds,
1150                         wimlib_progress_func_t progress_func)
1151 {
1152         int ret;
1153         bool found_link_cmd = false;
1154         bool found_nolink_cmd = false;
1155
1156         /* Select the image from which we are extracting files */
1157         ret = select_wim_image(wim, image);
1158         if (ret)
1159                 return ret;
1160
1161         /* Make sure there are no streams in the WIM that have not been
1162          * checksummed yet. */
1163         ret = wim_checksum_unhashed_streams(wim);
1164         if (ret)
1165                 return ret;
1166
1167         /* Check for problems with the extraction commands */
1168         for (size_t i = 0; i < num_cmds; i++) {
1169                 ret = check_extract_command(&cmds[i], wim->hdr.flags);
1170                 if (ret)
1171                         return ret;
1172                 if (cmds[i].extract_flags & (WIMLIB_EXTRACT_FLAG_SYMLINK |
1173                                              WIMLIB_EXTRACT_FLAG_HARDLINK)) {
1174                         found_link_cmd = true;
1175                 } else {
1176                         found_nolink_cmd = true;
1177                 }
1178                 if (found_link_cmd && found_nolink_cmd) {
1179                         ERROR("Symlink or hardlink extraction mode must "
1180                               "be set on all extraction commands");
1181                         return WIMLIB_ERR_INVALID_PARAM;
1182                 }
1183         }
1184
1185         /* Execute the extraction commands */
1186         for (size_t i = 0; i < num_cmds; i++) {
1187                 ret = extract_tree(wim,
1188                                    cmds[i].wim_source_path,
1189                                    cmds[i].fs_dest_path,
1190                                    cmds[i].extract_flags,
1191                                    progress_func);
1192                 if (ret)
1193                         return ret;
1194         }
1195         return 0;
1196 }
1197
1198 /* Extract files or directories from a WIM image. */
1199 WIMLIBAPI int
1200 wimlib_extract_files(WIMStruct *wim,
1201                      int image,
1202                      int default_extract_flags,
1203                      const struct wimlib_extract_command *cmds,
1204                      size_t num_cmds,
1205                      WIMStruct **additional_swms,
1206                      unsigned num_additional_swms,
1207                      wimlib_progress_func_t progress_func)
1208 {
1209         int ret;
1210         struct wimlib_extract_command *cmds_copy;
1211         struct wim_lookup_table *wim_tab_save, *joined_tab;
1212         int all_flags = 0;
1213
1214         default_extract_flags &= WIMLIB_EXTRACT_MASK_PUBLIC;
1215
1216         ret = verify_swm_set(wim, additional_swms, num_additional_swms);
1217         if (ret)
1218                 goto out;
1219
1220         if (num_additional_swms) {
1221                 ret = new_joined_lookup_table(wim, additional_swms,
1222                                               num_additional_swms,
1223                                               &joined_tab);
1224                 if (ret)
1225                         goto out;
1226                 wim_tab_save = wim->lookup_table;
1227                 wim->lookup_table = joined_tab;
1228         }
1229
1230         cmds_copy = CALLOC(num_cmds, sizeof(cmds[0]));
1231         if (!cmds_copy) {
1232                 ret = WIMLIB_ERR_NOMEM;
1233                 goto out_restore_lookup_table;
1234         }
1235
1236         for (size_t i = 0; i < num_cmds; i++) {
1237                 cmds_copy[i].extract_flags = (default_extract_flags |
1238                                                  cmds[i].extract_flags)
1239                                                 & WIMLIB_EXTRACT_MASK_PUBLIC;
1240                 all_flags |= cmds_copy[i].extract_flags;
1241
1242                 cmds_copy[i].wim_source_path = canonicalize_wim_path(cmds[i].wim_source_path);
1243                 if (!cmds_copy[i].wim_source_path) {
1244                         ret = WIMLIB_ERR_NOMEM;
1245                         goto out_free_cmds_copy;
1246                 }
1247
1248                 cmds_copy[i].fs_dest_path = canonicalize_fs_path(cmds[i].fs_dest_path);
1249                 if (!cmds_copy[i].fs_dest_path) {
1250                         ret = WIMLIB_ERR_NOMEM;
1251                         goto out_free_cmds_copy;
1252                 }
1253
1254         }
1255         ret = do_wimlib_extract_files(wim, image,
1256                                       cmds_copy, num_cmds,
1257                                       progress_func);
1258
1259         if (all_flags & (WIMLIB_EXTRACT_FLAG_SYMLINK |
1260                          WIMLIB_EXTRACT_FLAG_HARDLINK))
1261         {
1262                 for_lookup_table_entry(wim->lookup_table,
1263                                        lte_free_extracted_file, NULL);
1264         }
1265 out_free_cmds_copy:
1266         for (size_t i = 0; i < num_cmds; i++) {
1267                 FREE(cmds_copy[i].wim_source_path);
1268                 FREE(cmds_copy[i].fs_dest_path);
1269         }
1270         FREE(cmds_copy);
1271 out_restore_lookup_table:
1272         if (num_additional_swms) {
1273                 free_lookup_table(wim->lookup_table);
1274                 wim->lookup_table = wim_tab_save;
1275         }
1276 out:
1277         return ret;
1278 }
1279
1280 /*
1281  * Extracts an image from a WIM file.
1282  *
1283  * @wim:                WIMStruct for the WIM file.
1284  *
1285  * @image:              Number of the single image to extract.
1286  *
1287  * @target:             Directory or NTFS volume to extract the image to.
1288  *
1289  * @extract_flags:      Bitwise or of WIMLIB_EXTRACT_FLAG_*.
1290  *
1291  * @progress_func:      If non-NULL, a progress function to be called
1292  *                      periodically.
1293  *
1294  * Returns 0 on success; nonzero on failure.
1295  */
1296 static int
1297 extract_single_image(WIMStruct *wim, int image,
1298                      const tchar *target, int extract_flags,
1299                      wimlib_progress_func_t progress_func)
1300 {
1301         int ret;
1302         tchar *target_copy = canonicalize_fs_path(target);
1303         if (!target_copy)
1304                 return WIMLIB_ERR_NOMEM;
1305         struct wimlib_extract_command cmd = {
1306                 .wim_source_path = T(""),
1307                 .fs_dest_path = target_copy,
1308                 .extract_flags = extract_flags,
1309         };
1310         ret = do_wimlib_extract_files(wim, image, &cmd, 1, progress_func);
1311         FREE(target_copy);
1312         return ret;
1313 }
1314
1315 static const tchar * const filename_forbidden_chars =
1316 T(
1317 #ifdef __WIN32__
1318 "<>:\"/\\|?*"
1319 #else
1320 "/"
1321 #endif
1322 );
1323
1324 /* This function checks if it is okay to use a WIM image's name as a directory
1325  * name.  */
1326 static bool
1327 image_name_ok_as_dir(const tchar *image_name)
1328 {
1329         return image_name && *image_name &&
1330                 !tstrpbrk(image_name, filename_forbidden_chars);
1331 }
1332
1333 /* Extracts all images from the WIM to the directory @target, with the images
1334  * placed in subdirectories named by their image names. */
1335 static int
1336 extract_all_images(WIMStruct *wim,
1337                    const tchar *target,
1338                    int extract_flags,
1339                    wimlib_progress_func_t progress_func)
1340 {
1341         size_t image_name_max_len = max(xml_get_max_image_name_len(wim), 20);
1342         size_t output_path_len = tstrlen(target);
1343         tchar buf[output_path_len + 1 + image_name_max_len + 1];
1344         int ret;
1345         int image;
1346         const tchar *image_name;
1347
1348         ret = extract_directory(NULL, target, true);
1349         if (ret)
1350                 return ret;
1351
1352         tmemcpy(buf, target, output_path_len);
1353         buf[output_path_len] = T('/');
1354         for (image = 1; image <= wim->hdr.image_count; image++) {
1355                 image_name = wimlib_get_image_name(wim, image);
1356                 if (image_name_ok_as_dir(image_name)) {
1357                         tstrcpy(buf + output_path_len + 1, image_name);
1358                 } else {
1359                         /* Image name is empty or contains forbidden characters.
1360                          * Use image number instead. */
1361                         tsprintf(buf + output_path_len + 1, T("%d"), image);
1362                 }
1363                 ret = extract_single_image(wim, image, buf, extract_flags,
1364                                            progress_func);
1365                 if (ret)
1366                         return ret;
1367         }
1368         return 0;
1369 }
1370
1371 /* Extracts a single image or all images from a WIM file to a directory or NTFS
1372  * volume. */
1373 WIMLIBAPI int
1374 wimlib_extract_image(WIMStruct *wim,
1375                      int image,
1376                      const tchar *target,
1377                      int extract_flags,
1378                      WIMStruct **additional_swms,
1379                      unsigned num_additional_swms,
1380                      wimlib_progress_func_t progress_func)
1381 {
1382         struct wim_lookup_table *joined_tab, *wim_tab_save;
1383         int ret;
1384
1385         extract_flags &= WIMLIB_EXTRACT_MASK_PUBLIC;
1386
1387         ret = verify_swm_set(wim, additional_swms, num_additional_swms);
1388         if (ret)
1389                 return ret;
1390
1391         if (num_additional_swms) {
1392                 ret = new_joined_lookup_table(wim, additional_swms,
1393                                               num_additional_swms, &joined_tab);
1394                 if (ret)
1395                         return ret;
1396                 wim_tab_save = wim->lookup_table;
1397                 wim->lookup_table = joined_tab;
1398         }
1399
1400         if (image == WIMLIB_ALL_IMAGES) {
1401                 extract_flags |= WIMLIB_EXTRACT_FLAG_MULTI_IMAGE;
1402                 ret = extract_all_images(wim, target, extract_flags,
1403                                          progress_func);
1404         } else {
1405                 extract_flags &= ~WIMLIB_EXTRACT_FLAG_MULTI_IMAGE;
1406                 ret = extract_single_image(wim, image, target, extract_flags,
1407                                            progress_func);
1408         }
1409
1410         if (extract_flags & (WIMLIB_EXTRACT_FLAG_SYMLINK |
1411                              WIMLIB_EXTRACT_FLAG_HARDLINK))
1412         {
1413                 for_lookup_table_entry(wim->lookup_table,
1414                                        lte_free_extracted_file,
1415                                        NULL);
1416         }
1417         if (num_additional_swms) {
1418                 free_lookup_table(wim->lookup_table);
1419                 wim->lookup_table = wim_tab_save;
1420         }
1421         return ret;
1422 }