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