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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 #ifndef __WIN32__
  61
  62 /* Returns the number of components of @path.  */
  63 static unsigned
  64 get_num_path_components(const char *path)
  65 {
  66         unsigned num_components = 0;
  67         while (*path) {
  68                 while (*path == '/')
  69                         path++;
  70                 if (*path)
  71                         num_components++;
  72                 while (*path && *path != '/')
  73                         path++;
  74         }
  75         return num_components;
  76 }
  77
  78 static const char *
  79 path_next_part(const char *path)
  80 {
  81         while (*path && *path != '/')
  82                 path++;
  83         while (*path && *path == '/')
  84                 path++;
  85         return path;
  86 }
  87
  88 static int
  89 extract_regular_file_linked(struct wim_dentry *dentry,
  90                             const char *output_path,
  91                             struct apply_args *args,
  92                             struct wim_lookup_table_entry *lte)
  93 {
  94         /* This mode overrides the normal hard-link extraction and
  95          * instead either symlinks or hardlinks *all* identical files in
  96          * the WIM, even if they are in a different image (in the case
  97          * of a multi-image extraction) */
  98
  99         if (args->extract_flags & WIMLIB_EXTRACT_FLAG_HARDLINK) {
 100                 if (link(lte->extracted_file, output_path) != 0) {
 101                         ERROR_WITH_ERRNO("Failed to hard link "
 102                                          "`%s' to `%s'",
 103                                          output_path, lte->extracted_file);
 104                         return WIMLIB_ERR_LINK;
 105                 }
 106         } else {
 107                 int num_path_components;
 108                 int num_output_dir_path_components;
 109                 size_t extracted_file_len;
 110                 char *p;
 111                 const char *p2;
 112                 size_t i;
 113
 114                 num_path_components = get_num_path_components(dentry->_full_path) - 1;
 115                 num_output_dir_path_components = get_num_path_components(args->target);
 116
 117                 if (args->extract_flags & WIMLIB_EXTRACT_FLAG_MULTI_IMAGE) {
 118                         num_path_components++;
 119                         num_output_dir_path_components--;
 120                 }
 121                 extracted_file_len = strlen(lte->extracted_file);
 122
 123                 char buf[extracted_file_len + 3 * num_path_components + 1];
 124                 p = &buf[0];
 125
 126                 for (i = 0; i < num_path_components; i++) {
 127                         *p++ = '.';
 128                         *p++ = '.';
 129                         *p++ = '/';
 130                 }
 131                 p2 = lte->extracted_file;
 132                 while (*p2 == '/')
 133                         p2++;
 134                 while (num_output_dir_path_components > 0) {
 135                         p2 = path_next_part(p2);
 136                         num_output_dir_path_components--;
 137                 }
 138                 strcpy(p, p2);
 139                 if (symlink(buf, output_path) != 0) {
 140                         ERROR_WITH_ERRNO("Failed to symlink `%s' to `%s'",
 141                                          buf, lte->extracted_file);
 142                         return WIMLIB_ERR_LINK;
 143                 }
 144         }
 145         return 0;
 146 }
 147
 148 static int
 149 symlink_apply_unix_data(const char *link,
 150                         const struct wimlib_unix_data *unix_data)
 151 {
 152         if (lchown(link, unix_data->uid, unix_data->gid)) {
 153                 if (errno == EPERM) {
 154                         /* Ignore */
 155                         WARNING_WITH_ERRNO("failed to set symlink UNIX owner/group");
 156                 } else {
 157                         ERROR_WITH_ERRNO("failed to set symlink UNIX owner/group");
 158                         return WIMLIB_ERR_INVALID_DENTRY;
 159                 }
 160         }
 161         return 0;
 162 }
 163
 164 static int
 165 fd_apply_unix_data(int fd, const struct wimlib_unix_data *unix_data)
 166 {
 167         if (fchown(fd, unix_data->uid, unix_data->gid)) {
 168                 if (errno == EPERM) {
 169                         WARNING_WITH_ERRNO("failed to set file UNIX owner/group");
 170                         /* Ignore? */
 171                 } else {
 172                         ERROR_WITH_ERRNO("failed to set file UNIX owner/group");
 173                         return WIMLIB_ERR_INVALID_DENTRY;
 174                 }
 175         }
 176
 177         if (fchmod(fd, unix_data->mode)) {
 178                 if (errno == EPERM) {
 179                         WARNING_WITH_ERRNO("failed to set UNIX file mode");
 180                         /* Ignore? */
 181                 } else {
 182                         ERROR_WITH_ERRNO("failed to set UNIX file mode");
 183                         return WIMLIB_ERR_INVALID_DENTRY;
 184                 }
 185         }
 186         return 0;
 187 }
 188
 189 static int
 190 dir_apply_unix_data(const char *dir, const struct wimlib_unix_data *unix_data)
 191 {
 192         int dfd = open(dir, O_RDONLY);
 193         int ret;
 194         if (dfd >= 0) {
 195                 ret = fd_apply_unix_data(dfd, unix_data);
 196                 if (close(dfd)) {
 197                         ERROR_WITH_ERRNO("can't close directory `%s'", dir);
 198                         ret = WIMLIB_ERR_MKDIR;
 199                 }
 200         } else {
 201                 ERROR_WITH_ERRNO("can't open directory `%s'", dir);
 202                 ret = WIMLIB_ERR_MKDIR;
 203         }
 204         return ret;
 205 }
 206
 207 static int
 208 extract_regular_file_unlinked(struct wim_dentry *dentry,
 209                               struct apply_args *args,
 210                               const char *output_path,
 211                               struct wim_lookup_table_entry *lte)
 212 {
 213         /* Normal mode of extraction.  Regular files and hard links are
 214          * extracted in the way that they appear in the WIM. */
 215
 216         int out_fd;
 217         int ret;
 218         struct wim_inode *inode = dentry->d_inode;
 219
 220         if (!((args->extract_flags & WIMLIB_EXTRACT_FLAG_MULTI_IMAGE)
 221                 && (args->extract_flags & (WIMLIB_EXTRACT_FLAG_SYMLINK |
 222                                      WIMLIB_EXTRACT_FLAG_HARDLINK))))
 223         {
 224                 /* If the dentry is part of a hard link set of at least 2
 225                  * dentries and one of the other dentries has already been
 226                  * extracted, make a hard link to the file corresponding to this
 227                  * already-extracted directory.  Otherwise, extract the file and
 228                  * set the inode->i_extracted_file field so that other dentries
 229                  * in the hard link group can link to it. */
 230                 if (inode->i_nlink > 1) {
 231                         if (inode->i_extracted_file) {
 232                                 DEBUG("Extracting hard link `%s' => `%s'",
 233                                       output_path, inode->i_extracted_file);
 234                                 if (link(inode->i_extracted_file, output_path) != 0) {
 235                                         ERROR_WITH_ERRNO("Failed to hard link "
 236                                                          "`%s' to `%s'",
 237                                                          output_path,
 238                                                          inode->i_extracted_file);
 239                                         return WIMLIB_ERR_LINK;
 240                                 }
 241                                 return 0;
 242                         }
 243                         FREE(inode->i_extracted_file);
 244                         inode->i_extracted_file = STRDUP(output_path);
 245                         if (!inode->i_extracted_file) {
 246                                 ERROR("Failed to allocate memory for filename");
 247                                 return WIMLIB_ERR_NOMEM;
 248                         }
 249                 }
 250         }
 251
 252         /* Extract the contents of the file to @output_path. */
 253
 254         out_fd = open(output_path, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 255         if (out_fd == -1) {
 256                 ERROR_WITH_ERRNO("Failed to open the file `%s' for writing",
 257                                  output_path);
 258                 return WIMLIB_ERR_OPEN;
 259         }
 260
 261         if (!lte) {
 262                 /* Empty file with no lookup table entry */
 263                 DEBUG("Empty file `%s'.", output_path);
 264                 ret = 0;
 265                 goto out_extract_unix_data;
 266         }
 267
 268         ret = extract_wim_resource_to_fd(lte, out_fd, wim_resource_size(lte));
 269         if (ret) {
 270                 ERROR("Failed to extract resource to `%s'", output_path);
 271                 goto out;
 272         }
 273
 274 out_extract_unix_data:
 275         if (args->extract_flags & WIMLIB_EXTRACT_FLAG_UNIX_DATA) {
 276                 struct wimlib_unix_data unix_data;
 277                 ret = inode_get_unix_data(inode, &unix_data, NULL);
 278                 if (ret > 0)
 279                         ;
 280                 else if (ret < 0)
 281                         ret = 0;
 282                 else
 283                         ret = fd_apply_unix_data(out_fd, &unix_data);
 284                 if (ret)
 285                         goto out;
 286         }
 287         if (lte)
 288                 args->progress.extract.completed_bytes += wim_resource_size(lte);
 289 out:
 290         if (close(out_fd) != 0) {
 291                 ERROR_WITH_ERRNO("Failed to close file `%s'", output_path);
 292                 if (ret == 0)
 293                         ret = WIMLIB_ERR_WRITE;
 294         }
 295         return ret;
 296 }
 297
 298 static int
 299 extract_regular_file(struct wim_dentry *dentry,
 300                      struct apply_args *args,
 301                      const char *output_path)
 302 {
 303         struct wim_lookup_table_entry *lte;
 304         const struct wim_inode *inode = dentry->d_inode;
 305
 306         lte = inode_unnamed_lte_resolved(inode);
 307
 308         if (lte && (args->extract_flags & (WIMLIB_EXTRACT_FLAG_SYMLINK |
 309                                            WIMLIB_EXTRACT_FLAG_HARDLINK)))
 310         {
 311                 if (lte->extracted_file) {
 312                         return extract_regular_file_linked(dentry, output_path, args, lte);
 313                 } else {
 314                         lte->extracted_file = STRDUP(output_path);
 315                         if (!lte->extracted_file)
 316                                 return WIMLIB_ERR_NOMEM;
 317                 }
 318         }
 319         return extract_regular_file_unlinked(dentry, args, output_path, lte);
 320 }
 321
 322 static int
 323 extract_symlink(struct wim_dentry *dentry,
 324                 struct apply_args *args,
 325                 const char *output_path)
 326 {
 327         char target[4096 + args->target_realpath_len];
 328         char *fixed_target;
 329         const struct wim_inode *inode = dentry->d_inode;
 330
 331         ssize_t ret = wim_inode_readlink(inode,
 332                                          target + args->target_realpath_len,
 333                                          sizeof(target) - args->target_realpath_len - 1);
 334         struct wim_lookup_table_entry *lte;
 335
 336         if (ret <= 0) {
 337                 ERROR("Could not read the symbolic link from dentry `%s'",
 338                       dentry->_full_path);
 339                 return WIMLIB_ERR_INVALID_DENTRY;
 340         }
 341         target[args->target_realpath_len + ret] = '\0';
 342         if (target[args->target_realpath_len] == '/' &&
 343             args->extract_flags & WIMLIB_EXTRACT_FLAG_RPFIX)
 344         {
 345                 /* Fix absolute symbolic link target to point into the actual
 346                  * extraction destination */
 347                 memcpy(target, args->target_realpath,
 348                        args->target_realpath_len);
 349                 fixed_target = target;
 350         } else {
 351                 /* Keep same link target */
 352                 fixed_target = target + args->target_realpath_len;
 353         }
 354         ret = symlink(fixed_target, output_path);
 355         if (ret) {
 356                 ERROR_WITH_ERRNO("Failed to symlink `%s' to `%s'",
 357                                  output_path, fixed_target);
 358                 return WIMLIB_ERR_LINK;
 359         }
 360         if (args->extract_flags & WIMLIB_EXTRACT_FLAG_UNIX_DATA) {
 361                 struct wimlib_unix_data unix_data;
 362                 ret = inode_get_unix_data(inode, &unix_data, NULL);
 363                 if (ret > 0)
 364                         ;
 365                 else if (ret < 0)
 366                         ret = 0;
 367                 else
 368                         ret = symlink_apply_unix_data(output_path, &unix_data);
 369                 if (ret)
 370                         return ret;
 371         }
 372         lte = inode_unnamed_lte_resolved(inode);
 373         wimlib_assert(lte != NULL);
 374         args->progress.extract.completed_bytes += wim_resource_size(lte);
 375         return 0;
 376 }
 377
 378 #endif /* !__WIN32__ */
 379
 380 static int
 381 extract_directory(struct wim_dentry *dentry,
 382                   const tchar *output_path, bool is_root)
 383 {
 384         int ret;
 385         struct stat stbuf;
 386
 387         ret = tstat(output_path, &stbuf);
 388         if (ret == 0) {
 389                 if (S_ISDIR(stbuf.st_mode)) {
 390                         /*if (!is_root)*/
 391                                 /*WARNING("`%s' already exists", output_path);*/
 392                         goto dir_exists;
 393                 } else {
 394                         ERROR("`%"TS"' is not a directory", output_path);
 395                         return WIMLIB_ERR_MKDIR;
 396                 }
 397         } else {
 398                 if (errno != ENOENT) {
 399                         ERROR_WITH_ERRNO("Failed to stat `%"TS"'", output_path);
 400                         return WIMLIB_ERR_STAT;
 401                 }
 402         }
 403
 404         if (tmkdir(output_path, S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH))
 405         {
 406                 ERROR_WITH_ERRNO("Cannot create directory `%"TS"'", output_path);
 407                 return WIMLIB_ERR_MKDIR;
 408         }
 409 dir_exists:
 410         ret = 0;
 411 #ifndef __WIN32__
 412         if (dentry) {
 413                 struct wimlib_unix_data unix_data;
 414                 ret = inode_get_unix_data(dentry->d_inode, &unix_data, NULL);
 415                 if (ret > 0)
 416                         ;
 417                 else if (ret < 0)
 418                         ret = 0;
 419                 else
 420                         ret = dir_apply_unix_data(output_path, &unix_data);
 421         }
 422 #endif
 423         return ret;
 424 }
 425
 426 #ifndef __WIN32__
 427 static int
 428 unix_do_apply_dentry(const char *output_path, size_t output_path_len,
 429                      struct wim_dentry *dentry, struct apply_args *args)
 430 {
 431         const struct wim_inode *inode = dentry->d_inode;
 432
 433         if (inode_is_symlink(inode))
 434                 return extract_symlink(dentry, args, output_path);
 435         else if (inode_is_directory(inode))
 436                 return extract_directory((args->extract_flags &
 437                                            WIMLIB_EXTRACT_FLAG_UNIX_DATA) ? dentry : NULL,
 438                                          output_path, false);
 439         else
 440                 return extract_regular_file(dentry, args, output_path);
 441 }
 442
 443 static int
 444 unix_do_apply_dentry_timestamps(const char *output_path,
 445                                 size_t output_path_len,
 446                                 const struct wim_dentry *dentry,
 447                                 struct apply_args *args)
 448 {
 449         int ret;
 450         const struct wim_inode *inode = dentry->d_inode;
 451
 452 #ifdef HAVE_UTIMENSAT
 453         /* Convert the WIM timestamps, which are accurate to 100 nanoseconds,
 454          * into `struct timespec's for passing to utimensat(), which is accurate
 455          * to 1 nanosecond. */
 456
 457         struct timespec ts[2];
 458         ts[0] = wim_timestamp_to_timespec(inode->i_last_access_time);
 459         ts[1] = wim_timestamp_to_timespec(inode->i_last_write_time);
 460         ret = utimensat(AT_FDCWD, output_path, ts, AT_SYMLINK_NOFOLLOW);
 461         if (ret)
 462                 ret = errno;
 463 #else
 464         ret = ENOSYS;
 465 #endif
 466
 467         if (ret == ENOSYS) {
 468                 /* utimensat() not implemented or not available */
 469         #ifdef HAVE_LUTIMES
 470                 /* Convert the WIM timestamps, which are accurate to 100
 471                  * nanoseconds, into `struct timeval's for passing to lutimes(),
 472                  * which is accurate to 1 microsecond. */
 473                 struct timeval tv[2];
 474                 tv[0] = wim_timestamp_to_timeval(inode->i_last_access_time);
 475                 tv[1] = wim_timestamp_to_timeval(inode->i_last_write_time);
 476                 ret = lutimes(output_path, tv);
 477                 if (ret)
 478                         ret = errno;
 479         #endif
 480         }
 481
 482         if (ret == ENOSYS) {
 483                 /* utimensat() and lutimes() both not implemented or not
 484                  * available */
 485         #ifdef HAVE_UTIME
 486                 /* Convert the WIM timestamps, which are accurate to 100
 487                  * nanoseconds, into a `struct utimbuf's for passing to
 488                  * utime(), which is accurate to 1 second. */
 489                 struct utimbuf buf;
 490                 buf.actime = wim_timestamp_to_unix(inode->i_last_access_time);
 491                 buf.modtime = wim_timestamp_to_unix(inode->i_last_write_time);
 492                 ret = utime(output_path, &buf);
 493         #endif
 494         }
 495         if (ret && args->num_utime_warnings < 10) {
 496                 WARNING_WITH_ERRNO("Failed to set timestamp on file `%s'",
 497                                     output_path);
 498                 args->num_utime_warnings++;
 499         }
 500         return 0;
 501 }
 502 #endif /* !__WIN32__ */
 503
 504 /* Extracts a file, directory, or symbolic link from the WIM archive. */
 505 static int
 506 apply_dentry_normal(struct wim_dentry *dentry, void *arg)
 507 {
 508         struct apply_args *args = arg;
 509         size_t len;
 510         tchar *output_path;
 511
 512         len = tstrlen(args->target);
 513         if (dentry_is_root(dentry)) {
 514                 output_path = (tchar*)args->target;
 515         } else {
 516                 output_path = alloca(len * sizeof(tchar) + dentry->full_path_nbytes +
 517                                      sizeof(tchar));
 518                 memcpy(output_path, args->target, len * sizeof(tchar));
 519                 memcpy(output_path + len, dentry->_full_path, dentry->full_path_nbytes);
 520                 len += dentry->full_path_nbytes / sizeof(tchar);
 521                 output_path[len] = T('\0');
 522         }
 523 #ifdef __WIN32__
 524         return win32_do_apply_dentry(output_path, len, dentry, args);
 525 #else
 526         return unix_do_apply_dentry(output_path, len, dentry, args);
 527 #endif
 528 }
 529
 530
 531 /* Apply timestamps to an extracted file or directory */
 532 static int
 533 apply_dentry_timestamps_normal(struct wim_dentry *dentry, void *arg)
 534 {
 535         struct apply_args *args = arg;
 536         size_t len;
 537         tchar *output_path;
 538
 539         len = tstrlen(args->target);
 540         if (dentry_is_root(dentry)) {
 541                 output_path = (tchar*)args->target;
 542         } else {
 543                 output_path = alloca(len * sizeof(tchar) + dentry->full_path_nbytes +
 544                                      sizeof(tchar));
 545                 memcpy(output_path, args->target, len * sizeof(tchar));
 546                 memcpy(output_path + len, dentry->_full_path, dentry->full_path_nbytes);
 547                 len += dentry->full_path_nbytes / sizeof(tchar);
 548                 output_path[len] = T('\0');
 549         }
 550
 551 #ifdef __WIN32__
 552         return win32_do_apply_dentry_timestamps(output_path, len, dentry, args);
 553 #else
 554         return unix_do_apply_dentry_timestamps(output_path, len, dentry, args);
 555 #endif
 556 }
 557
 558 /* Extract a dentry if it hasn't already been extracted, and either the dentry
 559  * has no streams or WIMLIB_EXTRACT_FLAG_NO_STREAMS is not specified. */
 560 static int
 561 maybe_apply_dentry(struct wim_dentry *dentry, void *arg)
 562 {
 563         struct apply_args *args = arg;
 564         int ret;
 565
 566         if (dentry->is_extracted)
 567                 return 0;
 568
 569         if (args->extract_flags & WIMLIB_EXTRACT_FLAG_NO_STREAMS)
 570                 if (inode_unnamed_lte_resolved(dentry->d_inode) &&
 571                     !(dentry->d_inode->i_attributes & (FILE_ATTRIBUTE_DIRECTORY |
 572                                                        FILE_ATTRIBUTE_ENCRYPTED)))
 573                         return 0;
 574
 575         if ((args->extract_flags & WIMLIB_EXTRACT_FLAG_VERBOSE) &&
 576              args->progress_func) {
 577                 args->progress.extract.cur_path = dentry->_full_path;
 578                 args->progress_func(WIMLIB_PROGRESS_MSG_EXTRACT_DENTRY,
 579                                     &args->progress);
 580         }
 581         ret = args->apply_dentry(dentry, args);
 582         if (ret == 0)
 583                 dentry->is_extracted = 1;
 584         return ret;
 585 }
 586
 587 static void
 588 calculate_bytes_to_extract(struct list_head *stream_list,
 589                            int extract_flags,
 590                            union wimlib_progress_info *progress)
 591 {
 592         struct wim_lookup_table_entry *lte;
 593         u64 total_bytes = 0;
 594         u64 num_streams = 0;
 595
 596         /* For each stream to be extracted... */
 597         list_for_each_entry(lte, stream_list, extraction_list) {
 598                 if (extract_flags &
 599                     (WIMLIB_EXTRACT_FLAG_SYMLINK | WIMLIB_EXTRACT_FLAG_HARDLINK))
 600                 {
 601                         /* In the symlink or hard link extraction mode, each
 602                          * stream will be extracted one time regardless of how
 603                          * many dentries share the stream. */
 604                         wimlib_assert(!(extract_flags & WIMLIB_EXTRACT_FLAG_NTFS));
 605                         if (!lte->extracted_file) {
 606                                 num_streams++;
 607                                 total_bytes += wim_resource_size(lte);
 608                         }
 609                 } else {
 610                         num_streams += lte->out_refcnt;
 611                         total_bytes += lte->out_refcnt * wim_resource_size(lte);
 612                 }
 613         }
 614         progress->extract.num_streams = num_streams;
 615         progress->extract.total_bytes = total_bytes;
 616         progress->extract.completed_bytes = 0;
 617 }
 618
 619 static void
 620 maybe_add_stream_for_extraction(struct wim_lookup_table_entry *lte,
 621                                 struct list_head *stream_list)
 622 {
 623         if (++lte->out_refcnt == 1) {
 624                 INIT_LIST_HEAD(&lte->inode_list);
 625                 list_add_tail(&lte->extraction_list, stream_list);
 626         }
 627 }
 628
 629 static void
 630 inode_find_streams_for_extraction(struct wim_inode *inode,
 631                                   struct list_head *stream_list,
 632                                   int extract_flags)
 633 {
 634         struct wim_lookup_table_entry *lte;
 635         bool inode_added = false;
 636
 637         lte = inode_unnamed_lte_resolved(inode);
 638         if (lte) {
 639                 maybe_add_stream_for_extraction(lte, stream_list);
 640                 list_add_tail(&inode->i_lte_inode_list, &lte->inode_list);
 641                 inode_added = true;
 642         }
 643
 644         /* Determine whether to include alternate data stream entries or not.
 645          *
 646          * UNIX:  Include them if extracting using NTFS-3g.
 647          *
 648          * Windows: Include them undconditionally, although if the filesystem is
 649          * not NTFS we won't actually be able to extract them. */
 650 #if defined(WITH_NTFS_3G)
 651         if (extract_flags & WIMLIB_EXTRACT_FLAG_NTFS)
 652 #elif defined(__WIN32__)
 653         if (1)
 654 #else
 655         if (0)
 656 #endif
 657         {
 658                 for (unsigned i = 0; i < inode->i_num_ads; i++) {
 659                         if (inode->i_ads_entries[i].stream_name_nbytes != 0) {
 660                                 lte = inode->i_ads_entries[i].lte;
 661                                 if (lte) {
 662                                         maybe_add_stream_for_extraction(lte,
 663                                                                         stream_list);
 664                                         if (!inode_added) {
 665                                                 list_add_tail(&inode->i_lte_inode_list,
 666                                                               &lte->inode_list);
 667                                                 inode_added = true;
 668                                         }
 669                                 }
 670                         }
 671                 }
 672         }
 673 }
 674
 675 static void
 676 find_streams_for_extraction(struct wim_image_metadata *imd,
 677                             struct list_head *stream_list,
 678                             struct wim_lookup_table *lookup_table,
 679                             int extract_flags)
 680 {
 681         struct wim_inode *inode;
 682         struct wim_dentry *dentry;
 683
 684         for_lookup_table_entry(lookup_table, lte_zero_out_refcnt, NULL);
 685         INIT_LIST_HEAD(stream_list);
 686         image_for_each_inode(inode, imd) {
 687                 if (!inode->i_resolved)
 688                         inode_resolve_ltes(inode, lookup_table);
 689                 inode_for_each_dentry(dentry, inode)
 690                         dentry->is_extracted = 0;
 691                 inode_find_streams_for_extraction(inode, stream_list,
 692                                                   extract_flags);
 693         }
 694 }
 695
 696 struct apply_operations {
 697         int (*apply_dentry)(struct wim_dentry *dentry, void *arg);
 698         int (*apply_dentry_timestamps)(struct wim_dentry *dentry, void *arg);
 699 };
 700
 701 static const struct apply_operations normal_apply_operations = {
 702         .apply_dentry = apply_dentry_normal,
 703         .apply_dentry_timestamps = apply_dentry_timestamps_normal,
 704 };
 705
 706 #ifdef WITH_NTFS_3G
 707 static const struct apply_operations ntfs_apply_operations = {
 708         .apply_dentry = apply_dentry_ntfs,
 709         .apply_dentry_timestamps = apply_dentry_timestamps_ntfs,
 710 };
 711 #endif
 712
 713 static int
 714 apply_stream_list(struct list_head *stream_list,
 715                   struct apply_args *args,
 716                   const struct apply_operations *ops,
 717                   wimlib_progress_func_t progress_func)
 718 {
 719         uint64_t bytes_per_progress = args->progress.extract.total_bytes / 100;
 720         uint64_t next_progress = bytes_per_progress;
 721         struct wim_lookup_table_entry *lte;
 722         struct wim_inode *inode;
 723         struct wim_dentry *dentry;
 724         int ret;
 725
 726         /* This complicated loop is essentially looping through the dentries,
 727          * although dentries may be visited more than once (if a dentry contains
 728          * two different nonempty streams) or not at all (if a dentry contains
 729          * no non-empty streams).
 730          *
 731          * The outer loop is over the distinct streams to be extracted so that
 732          * sequential reading of the WIM can be implemented. */
 733
 734         /* For each distinct stream to be extracted */
 735         list_for_each_entry(lte, stream_list, extraction_list) {
 736                 /* For each inode that contains the stream */
 737                 list_for_each_entry(inode, &lte->inode_list, i_lte_inode_list) {
 738                         /* For each dentry that points to the inode */
 739                         inode_for_each_dentry(dentry, inode) {
 740                                 /* Extract the dentry if it was not already
 741                                  * extracted */
 742                                 ret = maybe_apply_dentry(dentry, args);
 743                                 if (ret)
 744                                         return ret;
 745                                 if (progress_func &&
 746                                     args->progress.extract.completed_bytes >= next_progress)
 747                                 {
 748                                         progress_func(WIMLIB_PROGRESS_MSG_EXTRACT_STREAMS,
 749                                                       &args->progress);
 750                                         if (args->progress.extract.completed_bytes >=
 751                                             args->progress.extract.total_bytes)
 752                                         {
 753                                                 next_progress = ~0ULL;
 754                                         } else {
 755                                                 next_progress =
 756                                                         min (args->progress.extract.completed_bytes +
 757                                                              bytes_per_progress,
 758                                                              args->progress.extract.total_bytes);
 759                                         }
 760                                 }
 761                         }
 762                 }
 763         }
 764         return 0;
 765 }
 766
 767 static int
 768 sort_stream_list_by_wim_position(struct list_head *stream_list)
 769 {
 770         struct list_head *cur;
 771         size_t num_streams;
 772         struct wim_lookup_table_entry **array;
 773         size_t i;
 774         size_t array_size;
 775
 776         num_streams = 0;
 777         list_for_each(cur, stream_list)
 778                 num_streams++;
 779         array_size = num_streams * sizeof(array[0]);
 780         array = MALLOC(array_size);
 781         if (!array) {
 782                 ERROR("Failed to allocate %zu bytes to sort stream entries",
 783                       array_size);
 784                 return WIMLIB_ERR_NOMEM;
 785         }
 786         cur = stream_list->next;
 787         for (i = 0; i < num_streams; i++) {
 788                 array[i] = container_of(cur, struct wim_lookup_table_entry, extraction_list);
 789                 cur = cur->next;
 790         }
 791
 792         qsort(array, num_streams, sizeof(array[0]), cmp_streams_by_wim_position);
 793
 794         INIT_LIST_HEAD(stream_list);
 795         for (i = 0; i < num_streams; i++)
 796                 list_add_tail(&array[i]->extraction_list, stream_list);
 797         FREE(array);
 798         return 0;
 799 }
 800
 801
 802 /* Extracts the image @image from the WIM @w to the directory or NTFS volume
 803  * @target. */
 804 static int
 805 extract_single_image(WIMStruct *w, int image,
 806                      const tchar *target, int extract_flags,
 807                      wimlib_progress_func_t progress_func)
 808 {
 809         int ret;
 810         struct list_head stream_list;
 811
 812         struct apply_args args;
 813         const struct apply_operations *ops;
 814
 815         memset(&args, 0, sizeof(args));
 816
 817         args.w                  = w;
 818         args.target             = target;
 819         args.extract_flags      = extract_flags;
 820         args.progress_func      = progress_func;
 821
 822         if (progress_func) {
 823                 args.progress.extract.wimfile_name = w->filename;
 824                 args.progress.extract.image = image;
 825                 args.progress.extract.extract_flags = (extract_flags &
 826                                                        WIMLIB_EXTRACT_MASK_PUBLIC);
 827                 args.progress.extract.image_name = wimlib_get_image_name(w, image);
 828                 args.progress.extract.target = target;
 829         }
 830
 831 #ifdef WITH_NTFS_3G
 832         if (extract_flags & WIMLIB_EXTRACT_FLAG_NTFS) {
 833                 args.vol = ntfs_mount(target, 0);
 834                 if (!args.vol) {
 835                         ERROR_WITH_ERRNO("Failed to mount NTFS volume `%"TS"'",
 836                                          target);
 837                         return WIMLIB_ERR_NTFS_3G;
 838                 }
 839                 ops = &ntfs_apply_operations;
 840         } else
 841 #endif
 842                 ops = &normal_apply_operations;
 843
 844         ret = select_wim_image(w, image);
 845         if (ret)
 846                 goto out;
 847
 848         /* Build a list of the streams that need to be extracted */
 849         find_streams_for_extraction(wim_get_current_image_metadata(w),
 850                                     &stream_list,
 851                                     w->lookup_table, extract_flags);
 852
 853         /* Calculate the number of bytes of data that will be extracted */
 854         calculate_bytes_to_extract(&stream_list, extract_flags,
 855                                    &args.progress);
 856
 857         if (progress_func) {
 858                 progress_func(WIMLIB_PROGRESS_MSG_EXTRACT_IMAGE_BEGIN,
 859                               &args.progress);
 860         }
 861
 862         /* If a sequential extraction was specified, sort the streams to be
 863          * extracted by their position in the WIM file, so that the WIM file can
 864          * be read sequentially. */
 865         if (extract_flags & WIMLIB_EXTRACT_FLAG_SEQUENTIAL) {
 866                 ret = sort_stream_list_by_wim_position(&stream_list);
 867                 if (ret != 0) {
 868                         WARNING("Falling back to non-sequential extraction");
 869                         extract_flags &= ~WIMLIB_EXTRACT_FLAG_SEQUENTIAL;
 870                 }
 871         }
 872
 873         if (progress_func) {
 874                 progress_func(WIMLIB_PROGRESS_MSG_EXTRACT_DIR_STRUCTURE_BEGIN,
 875                               &args.progress);
 876         }
 877
 878         ret = calculate_dentry_tree_full_paths(wim_root_dentry(w));
 879         if (ret)
 880                 goto out;
 881
 882         /* Make the directory structure and extract empty files */
 883         args.extract_flags |= WIMLIB_EXTRACT_FLAG_NO_STREAMS;
 884         args.apply_dentry = ops->apply_dentry;
 885         ret = for_dentry_in_tree(wim_root_dentry(w), maybe_apply_dentry, &args);
 886         args.extract_flags &= ~WIMLIB_EXTRACT_FLAG_NO_STREAMS;
 887         if (ret)
 888                 goto out;
 889
 890         if (progress_func) {
 891                 progress_func(WIMLIB_PROGRESS_MSG_EXTRACT_DIR_STRUCTURE_END,
 892                               &args.progress);
 893         }
 894
 895         if (extract_flags & WIMLIB_EXTRACT_FLAG_RPFIX) {
 896                 args.target_realpath = realpath(target, NULL);
 897                 if (!args.target_realpath)
 898                         return WIMLIB_ERR_NOMEM;
 899                 args.target_realpath_len = tstrlen(args.target_realpath);
 900         }
 901
 902         /* Extract non-empty files */
 903         ret = apply_stream_list(&stream_list, &args, ops, progress_func);
 904         if (ret)
 905                 goto out_free_target_realpath;
 906
 907         if (progress_func) {
 908                 progress_func(WIMLIB_PROGRESS_MSG_APPLY_TIMESTAMPS,
 909                               &args.progress);
 910         }
 911
 912         /* Apply timestamps */
 913         ret = for_dentry_in_tree_depth(wim_root_dentry(w),
 914                                        ops->apply_dentry_timestamps, &args);
 915         if (ret)
 916                 goto out_free_target_realpath;
 917
 918         if (progress_func) {
 919                 progress_func(WIMLIB_PROGRESS_MSG_EXTRACT_IMAGE_END,
 920                               &args.progress);
 921         }
 922 out_free_target_realpath:
 923         FREE(args.target_realpath);
 924 out:
 925 #ifdef WITH_NTFS_3G
 926         /* Unmount the NTFS volume */
 927         if (extract_flags & WIMLIB_EXTRACT_FLAG_NTFS) {
 928                 if (ntfs_umount(args.vol, FALSE) != 0) {
 929                         ERROR_WITH_ERRNO("Failed to unmount NTFS volume `%"TS"'",
 930                                          args.target);
 931                         if (ret == 0)
 932                                 ret = WIMLIB_ERR_NTFS_3G;
 933                 }
 934         }
 935 #endif
 936         return ret;
 937 }
 938
 939 static const tchar * const filename_forbidden_chars =
 940 T(
 941 #ifdef __WIN32__
 942 "<>:\"/\\|?*"
 943 #else
 944 "/"
 945 #endif
 946 );
 947
 948 /* This function checks if it is okay to use a WIM image's name as a directory
 949  * name.  */
 950 static bool
 951 image_name_ok_as_dir(const tchar *image_name)
 952 {
 953         return image_name && *image_name &&
 954                 !tstrpbrk(image_name, filename_forbidden_chars);
 955 }
 956
 957 /* Extracts all images from the WIM to the directory @target, with the images
 958  * placed in subdirectories named by their image names. */
 959 static int
 960 extract_all_images(WIMStruct *w,
 961                    const tchar *target,
 962                    int extract_flags,
 963                    wimlib_progress_func_t progress_func)
 964 {
 965         size_t image_name_max_len = max(xml_get_max_image_name_len(w), 20);
 966         size_t output_path_len = tstrlen(target);
 967         tchar buf[output_path_len + 1 + image_name_max_len + 1];
 968         int ret;
 969         int image;
 970         const tchar *image_name;
 971
 972         ret = extract_directory(NULL, target, true);
 973         if (ret)
 974                 return ret;
 975
 976         tmemcpy(buf, target, output_path_len);
 977         buf[output_path_len] = T('/');
 978         for (image = 1; image <= w->hdr.image_count; image++) {
 979                 image_name = wimlib_get_image_name(w, image);
 980                 if (image_name_ok_as_dir(image_name)) {
 981                         tstrcpy(buf + output_path_len + 1, image_name);
 982                 } else {
 983                         /* Image name is empty, or contains forbidden
 984                          * characters. */
 985                         tsprintf(buf + output_path_len + 1, T("%d"), image);
 986                 }
 987                 ret = extract_single_image(w, image, buf, extract_flags,
 988                                            progress_func);
 989                 if (ret != 0)
 990                         return ret;
 991         }
 992         return 0;
 993 }
 994
 995 /* Extracts a single image or all images from a WIM file to a directory or NTFS
 996  * volume. */
 997 WIMLIBAPI int
 998 wimlib_extract_image(WIMStruct *w,
 999                      int image,
1000                      const tchar *target,
1001                      int extract_flags,
1002                      WIMStruct **additional_swms,
1003                      unsigned num_additional_swms,
1004                      wimlib_progress_func_t progress_func)
1005 {
1006         struct wim_lookup_table *joined_tab, *w_tab_save;
1007         int ret;
1008
1009         if (!target)
1010                 return WIMLIB_ERR_INVALID_PARAM;
1011
1012         extract_flags &= WIMLIB_EXTRACT_MASK_PUBLIC;
1013
1014         if ((extract_flags & (WIMLIB_EXTRACT_FLAG_SYMLINK | WIMLIB_EXTRACT_FLAG_HARDLINK))
1015                         == (WIMLIB_EXTRACT_FLAG_SYMLINK | WIMLIB_EXTRACT_FLAG_HARDLINK))
1016                 return WIMLIB_ERR_INVALID_PARAM;
1017
1018 #ifdef __WIN32__
1019         if (extract_flags & WIMLIB_EXTRACT_FLAG_UNIX_DATA) {
1020                 ERROR("Extracting UNIX data is not supported on Windows");
1021                 return WIMLIB_ERR_INVALID_PARAM;
1022         }
1023         if (extract_flags & (WIMLIB_EXTRACT_FLAG_SYMLINK | WIMLIB_EXTRACT_FLAG_HARDLINK)) {
1024                 ERROR("Linked extraction modes are not supported on Windows");
1025                 return WIMLIB_ERR_INVALID_PARAM;
1026         }
1027 #endif
1028
1029         if (extract_flags & WIMLIB_EXTRACT_FLAG_NTFS) {
1030 #ifdef WITH_NTFS_3G
1031                 if ((extract_flags & (WIMLIB_EXTRACT_FLAG_SYMLINK | WIMLIB_EXTRACT_FLAG_HARDLINK))) {
1032                         ERROR("Cannot specify symlink or hardlink flags when applying\n"
1033                               "        directly to a NTFS volume");
1034                         return WIMLIB_ERR_INVALID_PARAM;
1035                 }
1036                 if (image == WIMLIB_ALL_IMAGES) {
1037                         ERROR("Can only apply a single image when applying "
1038                               "directly to a NTFS volume");
1039                         return WIMLIB_ERR_INVALID_PARAM;
1040                 }
1041                 if (extract_flags & WIMLIB_EXTRACT_FLAG_UNIX_DATA) {
1042                         ERROR("Cannot restore UNIX-specific data in the NTFS extraction mode");
1043                         return WIMLIB_ERR_INVALID_PARAM;
1044                 }
1045 #else
1046                 ERROR("wimlib was compiled without support for NTFS-3g, so");
1047                 ERROR("we cannot apply a WIM image directly to a NTFS volume");
1048                 return WIMLIB_ERR_UNSUPPORTED;
1049 #endif
1050         }
1051
1052         if ((extract_flags & (WIMLIB_EXTRACT_FLAG_RPFIX |
1053                               WIMLIB_EXTRACT_FLAG_RPFIX)) ==
1054                 (WIMLIB_EXTRACT_FLAG_RPFIX | WIMLIB_EXTRACT_FLAG_NORPFIX))
1055         {
1056                 ERROR("Cannot specify RPFIX and NORPFIX flags at the same time!");
1057                 return WIMLIB_ERR_INVALID_PARAM;
1058         }
1059
1060         if ((extract_flags & (WIMLIB_EXTRACT_FLAG_RPFIX |
1061                               WIMLIB_EXTRACT_FLAG_NORPFIX)) == 0)
1062                 if (w->hdr.flags & WIM_HDR_FLAG_RP_FIX)
1063                         extract_flags |= WIMLIB_EXTRACT_FLAG_RPFIX;
1064
1065         ret = verify_swm_set(w, additional_swms, num_additional_swms);
1066         if (ret)
1067                 return ret;
1068
1069         ret = wim_checksum_unhashed_streams(w);
1070         if (ret)
1071                 return ret;
1072
1073         if (num_additional_swms) {
1074                 ret = new_joined_lookup_table(w, additional_swms,
1075                                               num_additional_swms, &joined_tab);
1076                 if (ret)
1077                         return ret;
1078                 w_tab_save = w->lookup_table;
1079                 w->lookup_table = joined_tab;
1080         }
1081
1082         if (image == WIMLIB_ALL_IMAGES) {
1083                 extract_flags |= WIMLIB_EXTRACT_FLAG_MULTI_IMAGE;
1084                 ret = extract_all_images(w, target, extract_flags,
1085                                          progress_func);
1086         } else {
1087                 extract_flags &= ~WIMLIB_EXTRACT_FLAG_MULTI_IMAGE;
1088                 ret = extract_single_image(w, image, target, extract_flags,
1089                                            progress_func);
1090         }
1091
1092         if (extract_flags & (WIMLIB_EXTRACT_FLAG_SYMLINK |
1093                              WIMLIB_EXTRACT_FLAG_HARDLINK))
1094         {
1095                 for_lookup_table_entry(w->lookup_table,
1096                                        lte_free_extracted_file,
1097                                        NULL);
1098         }
1099
1100         if (num_additional_swms) {
1101                 free_lookup_table(w->lookup_table);
1102                 w->lookup_table = w_tab_save;
1103         }
1104         return ret;
1105 }