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

   1 /*
   2  * update_image.c - Update a WIM image.
   3  */
   4
   5 /*
   6  * Copyright (C) 2013 Eric Biggers
   7  *
   8  * This file is part of wimlib, a library for working with WIM files.
   9  *
  10  * wimlib is free software; you can redistribute it and/or modify it under the
  11  * terms of the GNU General Public License as published by the Free
  12  * Software Foundation; either version 3 of the License, or (at your option)
  13  * any later version.
  14  *
  15  * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY
  16  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
  17  * A PARTICULAR PURPOSE. See the GNU General Public License for more
  18  * details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with wimlib; if not, see http://www.gnu.org/licenses/.
  22  */
  23
  24 #include "wimlib_internal.h"
  25 #include "dentry.h"
  26 #include "lookup_table.h"
  27 #include "security.h"
  28 #include "xml.h"
  29 #include <errno.h>
  30
  31 /* Overlays @branch onto @target, both of which must be directories. */
  32 static int
  33 do_overlay(struct wim_dentry *target, struct wim_dentry *branch)
  34 {
  35         struct rb_root *rb_root;
  36
  37         DEBUG("Doing overlay \"%"WS"\" => \"%"WS"\"",
  38               branch->file_name, target->file_name);
  39
  40         if (!dentry_is_directory(branch) || !dentry_is_directory(target)) {
  41                 ERROR("Cannot overlay \"%"WS"\" onto existing dentry: "
  42                       "is not directory-on-directory!", branch->file_name);
  43                 return WIMLIB_ERR_INVALID_OVERLAY;
  44         }
  45
  46         rb_root = &branch->d_inode->i_children;
  47         while (rb_root->rb_node) { /* While @branch has children... */
  48                 struct wim_dentry *child = rbnode_dentry(rb_root->rb_node);
  49                 struct wim_dentry *existing;
  50
  51                 /* Move @child to the directory @target */
  52                 unlink_dentry(child);
  53                 existing = dentry_add_child(target, child);
  54
  55                 /* File or directory with same name already exists */
  56                 if (existing) {
  57                         int ret;
  58                         ret = do_overlay(existing, child);
  59                         if (ret) {
  60                                 /* Overlay failed.  Revert the change to avoid
  61                                  * leaking the directory tree rooted at @child.
  62                                  * */
  63                                 dentry_add_child(branch, child);
  64                                 return ret;
  65                         }
  66                 }
  67         }
  68         free_dentry(branch);
  69         return 0;
  70 }
  71
  72 /* Attach or overlay a branch onto the WIM image.
  73  *
  74  * @root_p:
  75  *      Pointer to the root of the WIM image, or pointer to NULL if it has not
  76  *      been created yet.
  77  * @branch
  78  *      Branch to add.
  79  * @target_path:
  80  *      Path in the WIM image to add the branch, with leading and trailing
  81  *      slashes stripped.
  82  */
  83 static int
  84 attach_branch(struct wim_dentry **root_p, struct wim_dentry *branch,
  85               tchar *target_path)
  86 {
  87         tchar *slash;
  88         struct wim_dentry *dentry, *parent, *target;
  89         int ret;
  90
  91         DEBUG("Attaching branch \"%"WS"\" => \"%"TS"\"",
  92               branch->file_name, target_path);
  93
  94         if (*target_path == T('\0')) {
  95                 /* Target: root directory */
  96                 if (*root_p) {
  97                         /* Overlay on existing root */
  98                         return do_overlay(*root_p, branch);
  99                 } else {
 100                         if (!dentry_is_directory(branch)) {
 101                                 ERROR("Cannot set non-directory as root of WIM image");
 102                                 return WIMLIB_ERR_NOTDIR;
 103                         }
 104                         /* Set as root */
 105                         *root_p = branch;
 106                         return 0;
 107                 }
 108         }
 109
 110         /* Adding a non-root branch.  Create root if it hasn't been created
 111          * already. */
 112         if (!*root_p) {
 113                 ret  = new_filler_directory(T(""), root_p);
 114                 if (ret)
 115                         return ret;
 116         }
 117
 118         /* Walk the path to the branch, creating filler directories as needed.
 119          * */
 120         parent = *root_p;
 121         while ((slash = tstrchr(target_path, T('/')))) {
 122                 *slash = T('\0');
 123                 dentry = get_dentry_child_with_name(parent, target_path);
 124                 if (!dentry) {
 125                         ret = new_filler_directory(target_path, &dentry);
 126                         if (ret)
 127                                 return ret;
 128                         dentry_add_child(parent, dentry);
 129                 }
 130                 parent = dentry;
 131                 target_path = slash;
 132                 /* Skip over slashes.  Note: this cannot overrun the length of
 133                  * the string because the last character cannot be a slash, as
 134                  * trailing slashes were tripped.  */
 135                 do {
 136                         ++target_path;
 137                 } while (*target_path == T('/'));
 138         }
 139
 140         /* If the target path already existed, overlay the branch onto it.
 141          * Otherwise, set the branch as the target path. */
 142         target = get_dentry_child_with_utf16le_name(parent, branch->file_name,
 143                                                     branch->file_name_nbytes);
 144         if (target) {
 145                 return do_overlay(target, branch);
 146         } else {
 147                 dentry_add_child(parent, branch);
 148                 return 0;
 149         }
 150 }
 151
 152 static int
 153 execute_add_command(WIMStruct *wim,
 154                     const struct wimlib_update_command *add_cmd,
 155                     wimlib_progress_func_t progress_func)
 156 {
 157         int ret;
 158         int add_flags;
 159         tchar *fs_source_path;
 160         tchar *wim_target_path;
 161         struct wim_inode_table inode_table;
 162         struct sd_set sd_set;
 163         struct wim_image_metadata *imd;
 164         struct list_head unhashed_streams;
 165         struct add_image_params params;
 166         int (*capture_tree)(struct wim_dentry **,
 167                             const tchar *,
 168                             struct add_image_params *);
 169         union wimlib_progress_info progress;
 170         struct wimlib_capture_config *config;
 171 #ifdef WITH_NTFS_3G
 172         struct _ntfs_volume *ntfs_vol = NULL;
 173 #endif
 174         void *extra_arg;
 175         struct wim_dentry *branch;
 176         bool rollback_sd = true;
 177
 178         wimlib_assert(add_cmd->op == WIMLIB_UPDATE_OP_ADD);
 179         add_flags = add_cmd->add.add_flags;
 180         fs_source_path = add_cmd->add.fs_source_path;
 181         wim_target_path = add_cmd->add.wim_target_path;
 182         config = add_cmd->add.config;
 183         DEBUG("fs_source_path=\"%"TS"\", wim_target_path=\"%"TS"\", add_flags=%#x",
 184               fs_source_path, wim_target_path, add_flags);
 185
 186         imd = wim->image_metadata[wim->current_image - 1];
 187
 188         if (add_flags & WIMLIB_ADD_FLAG_NTFS) {
 189         #ifdef WITH_NTFS_3G
 190                 capture_tree = build_dentry_tree_ntfs;
 191                 extra_arg = &ntfs_vol;
 192                 if (imd->ntfs_vol != NULL) {
 193                         ERROR("NTFS volume already set");
 194                         ret = WIMLIB_ERR_INVALID_PARAM;
 195                         goto out;
 196                 }
 197         #else
 198                 ret = WIMLIB_ERR_INVALID_PARAM;
 199                 goto out;
 200         #endif
 201         } else {
 202         #ifdef __WIN32__
 203                 capture_tree = win32_build_dentry_tree;
 204         #else
 205                 capture_tree = unix_build_dentry_tree;
 206         #endif
 207                 extra_arg = NULL;
 208         }
 209
 210         ret = init_inode_table(&inode_table, 9001);
 211         if (ret)
 212                 goto out;
 213
 214         ret = init_sd_set(&sd_set, imd->security_data);
 215         if (ret)
 216                 goto out_destroy_inode_table;
 217
 218         INIT_LIST_HEAD(&unhashed_streams);
 219         wim->lookup_table->unhashed_streams = &unhashed_streams;
 220         params.lookup_table = wim->lookup_table;
 221         params.inode_table = &inode_table;
 222         params.sd_set = &sd_set;
 223         params.config = config;
 224         params.add_flags = add_flags;
 225         params.progress_func = progress_func;
 226         params.extra_arg = extra_arg;
 227
 228         if (progress_func) {
 229                 memset(&progress, 0, sizeof(progress));
 230                 progress.scan.source = fs_source_path;
 231                 progress.scan.wim_target_path = wim_target_path;
 232                 progress_func(WIMLIB_PROGRESS_MSG_SCAN_BEGIN, &progress);
 233         }
 234         config->_prefix = fs_source_path;
 235         config->_prefix_num_tchars = tstrlen(fs_source_path);
 236
 237         if (wim_target_path[0] == T('\0'))
 238                 add_flags |= WIMLIB_ADD_FLAG_ROOT;
 239         ret = (*capture_tree)(&branch, fs_source_path, &params);
 240         if (ret) {
 241                 ERROR("Failed to build dentry tree for \"%"TS"\"",
 242                       fs_source_path);
 243                 goto out_destroy_sd_set;
 244         }
 245         if (branch) {
 246                 /* Use the target name, not the source name, for
 247                  * the root of each branch from a capture
 248                  * source.  (This will also set the root dentry
 249                  * of the entire image to be unnamed.) */
 250                 ret = set_dentry_name(branch,
 251                                       path_basename(wim_target_path));
 252                 if (ret)
 253                         goto out_ntfs_umount;
 254
 255                 ret = attach_branch(&imd->root_dentry, branch, wim_target_path);
 256                 if (ret)
 257                         goto out_ntfs_umount;
 258         }
 259         if (progress_func)
 260                 progress_func(WIMLIB_PROGRESS_MSG_SCAN_END, &progress);
 261         list_splice_tail(&unhashed_streams, &imd->unhashed_streams);
 262 #ifdef WITH_NTFS_3G
 263         imd->ntfs_vol = ntfs_vol;
 264 #endif
 265         inode_table_prepare_inode_list(&inode_table, &imd->inode_list);
 266         ret = 0;
 267         rollback_sd = false;
 268         if (add_flags & WIMLIB_ADD_FLAG_RPFIX)
 269                 wim->hdr.flags |= WIM_HDR_FLAG_RP_FIX;
 270         goto out_destroy_sd_set;
 271 out_ntfs_umount:
 272 #ifdef WITH_NTFS_3G
 273         if (ntfs_vol)
 274                 do_ntfs_umount(ntfs_vol);
 275 #endif
 276         free_dentry_tree(branch, wim->lookup_table);
 277 out_destroy_sd_set:
 278         destroy_sd_set(&sd_set, rollback_sd);
 279 out_destroy_inode_table:
 280         destroy_inode_table(&inode_table);
 281 out:
 282         return ret;
 283 }
 284
 285 static int
 286 execute_delete_command(WIMStruct *wim,
 287                        const struct wimlib_update_command *delete_cmd)
 288 {
 289         int flags;
 290         const tchar *wim_path;
 291         struct wim_dentry *tree;
 292         bool is_root;
 293
 294         wimlib_assert(delete_cmd->op == WIMLIB_UPDATE_OP_DELETE);
 295         flags = delete_cmd->delete.delete_flags;
 296         wim_path = delete_cmd->delete.wim_path;
 297
 298         tree = get_dentry(wim, wim_path);
 299         if (!tree) {
 300                 /* Path to delete does not exist in the WIM. */
 301                 if (flags & WIMLIB_DELETE_FLAG_FORCE) {
 302                         return 0;
 303                 } else {
 304                         ERROR("Path \"%"TS"\" does not exist in WIM image %d",
 305                               wim_path, wim->current_image);
 306                         return WIMLIB_ERR_PATH_DOES_NOT_EXIST;
 307                 }
 308         }
 309
 310         if (dentry_is_directory(tree) && !(flags & WIMLIB_DELETE_FLAG_RECURSIVE)) {
 311                 ERROR("Path \"%"TS"\" in WIM image %d is a directory "
 312                       "but a recursive delete was not requested",
 313                       wim_path, wim->current_image);
 314                 return WIMLIB_ERR_IS_DIRECTORY;
 315         }
 316
 317         is_root = dentry_is_root(tree);
 318         unlink_dentry(tree);
 319         free_dentry_tree(tree, wim->lookup_table);
 320         if (is_root)
 321                 wim->image_metadata[wim->current_image - 1]->root_dentry = NULL;
 322         return 0;
 323 }
 324
 325 /*
 326  * Rename a file or directory in the WIM.
 327  *
 328  * This is also called from wimfs_rename() in the FUSE mount code.
 329  */
 330 int
 331 rename_wim_path(WIMStruct *wim, const tchar *from, const tchar *to)
 332 {
 333         struct wim_dentry *src;
 334         struct wim_dentry *dst;
 335         struct wim_dentry *parent_of_dst;
 336         int ret;
 337
 338         /* This rename() implementation currently only supports actual files
 339          * (not alternate data streams) */
 340
 341         src = get_dentry(wim, from);
 342         if (!src)
 343                 return -errno;
 344
 345         dst = get_dentry(wim, to);
 346
 347         if (dst) {
 348                 /* Destination file exists */
 349
 350                 if (src == dst) /* Same file */
 351                         return 0;
 352
 353                 if (!dentry_is_directory(src)) {
 354                         /* Cannot rename non-directory to directory. */
 355                         if (dentry_is_directory(dst))
 356                                 return -EISDIR;
 357                 } else {
 358                         /* Cannot rename directory to a non-directory or a non-empty
 359                          * directory */
 360                         if (!dentry_is_directory(dst))
 361                                 return -ENOTDIR;
 362                         if (inode_has_children(dst->d_inode))
 363                                 return -ENOTEMPTY;
 364                 }
 365                 parent_of_dst = dst->parent;
 366         } else {
 367                 /* Destination does not exist */
 368                 parent_of_dst = get_parent_dentry(wim, to);
 369                 if (!parent_of_dst)
 370                         return -errno;
 371
 372                 if (!dentry_is_directory(parent_of_dst))
 373                         return -ENOTDIR;
 374         }
 375
 376         ret = set_dentry_name(src, path_basename(to));
 377         if (ret)
 378                 return -ENOMEM;
 379         if (dst) {
 380                 unlink_dentry(dst);
 381                 free_dentry_tree(dst, wim->lookup_table);
 382         }
 383         unlink_dentry(src);
 384         dentry_add_child(parent_of_dst, src);
 385         return 0;
 386 }
 387
 388
 389 static int
 390 execute_rename_command(WIMStruct *wim,
 391                        const struct wimlib_update_command *rename_cmd)
 392 {
 393         int ret;
 394
 395         wimlib_assert(rename_cmd->op == WIMLIB_UPDATE_OP_RENAME);
 396
 397         ret = rename_wim_path(wim, rename_cmd->rename.wim_source_path,
 398                               rename_cmd->rename.wim_target_path);
 399         if (ret) {
 400                 switch (ret) {
 401                 case -ENOMEM:
 402                         ret = WIMLIB_ERR_NOMEM;
 403                         break;
 404                 case -ENOTDIR:
 405                         ret = WIMLIB_ERR_NOTDIR;
 406                         break;
 407                 case -ENOTEMPTY:
 408                         ret = WIMLIB_ERR_NOTEMPTY;
 409                         break;
 410                 case -EISDIR:
 411                         ret = WIMLIB_ERR_IS_DIRECTORY;
 412                         break;
 413                 case -ENOENT:
 414                 default:
 415                         ret = WIMLIB_ERR_PATH_DOES_NOT_EXIST;
 416                         break;
 417                 }
 418         }
 419         return ret;
 420 }
 421
 422 static inline const tchar *
 423 update_op_to_str(int op)
 424 {
 425         switch (op) {
 426         case WIMLIB_UPDATE_OP_ADD:
 427                 return T("add");
 428         case WIMLIB_UPDATE_OP_DELETE:
 429                 return T("delete");
 430         case WIMLIB_UPDATE_OP_RENAME:
 431                 return T("rename");
 432         default:
 433                 return T("???");
 434         }
 435 }
 436
 437 static int
 438 execute_update_commands(WIMStruct *wim,
 439                         const struct wimlib_update_command *cmds,
 440                         size_t num_cmds,
 441                         wimlib_progress_func_t progress_func)
 442 {
 443         int ret = 0;
 444         for (size_t i = 0; i < num_cmds; i++) {
 445                 DEBUG("Executing update command %zu of %zu (op=%"TS")",
 446                       i + 1, num_cmds, update_op_to_str(cmds[i].op));
 447                 switch (cmds[i].op) {
 448                 case WIMLIB_UPDATE_OP_ADD:
 449                         ret = execute_add_command(wim, &cmds[i], progress_func);
 450                         break;
 451                 case WIMLIB_UPDATE_OP_DELETE:
 452                         ret = execute_delete_command(wim, &cmds[i]);
 453                         if (ret == 0)
 454                                 wim->deletion_occurred = 1;
 455                         break;
 456                 case WIMLIB_UPDATE_OP_RENAME:
 457                         ret = execute_rename_command(wim, &cmds[i]);
 458                         break;
 459                 default:
 460                         wimlib_assert(0);
 461                         break;
 462                 }
 463                 if (ret)
 464                         break;
 465         }
 466         return ret;
 467 }
 468
 469 static int
 470 check_add_command(struct wimlib_update_command *cmd,
 471                   const struct wim_header *hdr)
 472 {
 473         int add_flags = cmd->add.add_flags;
 474
 475         /* Are we adding the entire image or not?  An empty wim_target_path
 476          * indicates that the tree we're adding is to be placed in the root of
 477          * the image.  We consider this to be capturing the entire image,
 478          * although it could potentially be an overlay on an existing root as
 479          * well. */
 480         bool is_entire_image = cmd->add.wim_target_path[0] == T('\0');
 481
 482 #ifdef __WIN32__
 483         /* Check for flags not supported on Windows */
 484         if (add_flags & WIMLIB_ADD_FLAG_NTFS) {
 485                 ERROR("wimlib was compiled without support for NTFS-3g, so");
 486                 ERROR("we cannot capture a WIM image directly from a NTFS volume");
 487                 return WIMLIB_ERR_UNSUPPORTED;
 488         }
 489         if (add_flags & WIMLIB_ADD_FLAG_UNIX_DATA) {
 490                 ERROR("Capturing UNIX-specific data is not supported on Windows");
 491                 return WIMLIB_ERR_UNSUPPORTED;
 492         }
 493         if (add_flags & WIMLIB_ADD_FLAG_DEREFERENCE) {
 494                 ERROR("Dereferencing symbolic links is not supported on Windows");
 495                 return WIMLIB_ERR_UNSUPPORTED;
 496         }
 497 #endif
 498
 499         /* VERBOSE implies EXCLUDE_VERBOSE */
 500         if (add_flags & WIMLIB_ADD_FLAG_VERBOSE)
 501                 add_flags |= WIMLIB_ADD_FLAG_EXCLUDE_VERBOSE;
 502
 503         /* Check for contradictory reparse point fixup flags */
 504         if ((add_flags & (WIMLIB_ADD_FLAG_RPFIX |
 505                           WIMLIB_ADD_FLAG_NORPFIX)) ==
 506                 (WIMLIB_ADD_FLAG_RPFIX |
 507                  WIMLIB_ADD_FLAG_NORPFIX))
 508         {
 509                 ERROR("Cannot specify RPFIX and NORPFIX flags "
 510                       "at the same time!");
 511                 return WIMLIB_ERR_INVALID_PARAM;
 512         }
 513
 514         /* Set default behavior on reparse point fixups if requested */
 515         if ((add_flags & (WIMLIB_ADD_FLAG_RPFIX |
 516                           WIMLIB_ADD_FLAG_NORPFIX)) == 0)
 517         {
 518                 /* Do reparse-point fixups by default if we are capturing an
 519                  * entire image and either the header flag is set from previous
 520                  * images, or if this is the first image being added. */
 521                 if (is_entire_image &&
 522                     ((hdr->flags & WIM_HDR_FLAG_RP_FIX) || hdr->image_count == 1))
 523                         add_flags |= WIMLIB_ADD_FLAG_RPFIX;
 524         }
 525
 526         if (!is_entire_image) {
 527                 if (add_flags & WIMLIB_ADD_FLAG_NTFS) {
 528                         ERROR("Cannot add directly from a NTFS volume "
 529                               "when not capturing a full image!");
 530                         return WIMLIB_ERR_INVALID_PARAM;
 531                 }
 532
 533                 if (add_flags & WIMLIB_ADD_FLAG_RPFIX) {
 534                         ERROR("Cannot do reparse point fixups when "
 535                               "not capturing a full image!");
 536                         return WIMLIB_ERR_INVALID_PARAM;
 537                 }
 538         }
 539         /* We may have modified the add flags. */
 540         cmd->add.add_flags = add_flags;
 541         return 0;
 542 }
 543
 544 static int
 545 check_update_command(struct wimlib_update_command *cmd,
 546                      const struct wim_header *hdr)
 547 {
 548         switch (cmd->op) {
 549         case WIMLIB_UPDATE_OP_ADD:
 550                 return check_add_command(cmd, hdr);
 551         case WIMLIB_UPDATE_OP_DELETE:
 552         case WIMLIB_UPDATE_OP_RENAME:
 553                 break;
 554         }
 555         return 0;
 556 }
 557
 558 static int
 559 check_update_commands(struct wimlib_update_command *cmds, size_t num_cmds,
 560                       const struct wim_header *hdr)
 561 {
 562         int ret = 0;
 563         for (size_t i = 0; i < num_cmds; i++) {
 564                 ret = check_update_command(&cmds[i], hdr);
 565                 if (ret)
 566                         break;
 567         }
 568         return ret;
 569 }
 570
 571
 572 extern void
 573 free_update_commands(struct wimlib_update_command *cmds, size_t num_cmds)
 574 {
 575         if (cmds) {
 576                 for (size_t i = 0; i < num_cmds; i++) {
 577                         switch (cmds->op) {
 578                         case WIMLIB_UPDATE_OP_ADD:
 579                                 FREE(cmds[i].add.fs_source_path);
 580                                 FREE(cmds[i].add.wim_target_path);
 581                                 free_capture_config(cmds[i].add.config);
 582                                 break;
 583                         case WIMLIB_UPDATE_OP_DELETE:
 584                                 FREE(cmds[i].delete.wim_path);
 585                                 break;
 586                         case WIMLIB_UPDATE_OP_RENAME:
 587                                 FREE(cmds[i].rename.wim_source_path);
 588                                 FREE(cmds[i].rename.wim_target_path);
 589                                 break;
 590                         }
 591                 }
 592                 FREE(cmds);
 593         }
 594 }
 595
 596 static int
 597 copy_update_commands(const struct wimlib_update_command *cmds,
 598                      size_t num_cmds,
 599                      struct wimlib_update_command **cmds_copy_ret)
 600 {
 601         int ret;
 602         struct wimlib_update_command *cmds_copy;
 603
 604         cmds_copy = CALLOC(num_cmds, sizeof(cmds[0]));
 605         if (!cmds_copy)
 606                 goto oom;
 607
 608         for (size_t i = 0; i < num_cmds; i++) {
 609                 cmds_copy[i].op = cmds[i].op;
 610                 switch (cmds[i].op) {
 611                 case WIMLIB_UPDATE_OP_ADD:
 612                         cmds_copy[i].add.fs_source_path =
 613                                 canonicalize_fs_path(cmds[i].add.fs_source_path);
 614                         cmds_copy[i].add.wim_target_path =
 615                                 canonicalize_wim_path(cmds[i].add.wim_target_path);
 616                         if (!cmds_copy[i].add.fs_source_path ||
 617                             !cmds_copy[i].add.wim_target_path)
 618                                 goto oom;
 619                         if (cmds[i].add.config) {
 620                                 ret = copy_and_canonicalize_capture_config(cmds[i].add.config,
 621                                                                            &cmds_copy[i].add.config);
 622                                 if (ret)
 623                                         goto err;
 624                         }
 625                         cmds_copy[i].add.add_flags = cmds[i].add.add_flags;
 626                         break;
 627                 case WIMLIB_UPDATE_OP_DELETE:
 628                         cmds_copy[i].delete.wim_path =
 629                                 canonicalize_wim_path(cmds[i].delete.wim_path);
 630                         if (!cmds_copy[i].delete.wim_path)
 631                                 goto oom;
 632                         cmds_copy[i].delete.delete_flags = cmds[i].delete.delete_flags;
 633                         break;
 634                 case WIMLIB_UPDATE_OP_RENAME:
 635                         cmds_copy[i].rename.wim_source_path =
 636                                 canonicalize_wim_path(cmds[i].rename.wim_source_path);
 637                         cmds_copy[i].rename.wim_target_path =
 638                                 canonicalize_wim_path(cmds[i].rename.wim_target_path);
 639                         if (!cmds_copy[i].rename.wim_source_path ||
 640                             !cmds_copy[i].rename.wim_target_path)
 641                                 goto oom;
 642                         break;
 643                 default:
 644                         ERROR("Unknown update operation %u", cmds[i].op);
 645                         ret = WIMLIB_ERR_INVALID_PARAM;
 646                         goto err;
 647                 }
 648         }
 649         *cmds_copy_ret = cmds_copy;
 650         ret = 0;
 651 out:
 652         return ret;
 653 oom:
 654         ret = WIMLIB_ERR_NOMEM;
 655 err:
 656         free_update_commands(cmds_copy, num_cmds);
 657         goto out;
 658 }
 659
 660 /*
 661  * Entry point for making a series of updates to a WIM image.
 662  */
 663 WIMLIBAPI int
 664 wimlib_update_image(WIMStruct *wim,
 665                     int image,
 666                     const struct wimlib_update_command *cmds,
 667                     size_t num_cmds,
 668                     int update_flags,
 669                     wimlib_progress_func_t progress_func)
 670 {
 671         int ret;
 672         struct wimlib_update_command *cmds_copy;
 673
 674         DEBUG("Updating image %d with %zu commands", image, num_cmds);
 675
 676         /* Refuse to update a split WIM. */
 677         if (wim->hdr.total_parts != 1) {
 678                 ERROR("Cannot update a split WIM!");
 679                 ret = WIMLIB_ERR_SPLIT_UNSUPPORTED;
 680                 goto out;
 681         }
 682
 683         /* Load the metadata for the image to modify (if not loaded already) */
 684         ret = select_wim_image(wim, image);
 685         if (ret)
 686                 goto out;
 687
 688         /* Short circuit a successful return if no commands were specified.
 689          * Avoids problems with trying to allocate 0 bytes of memory. */
 690         if (num_cmds == 0)
 691                 goto out;
 692
 693         DEBUG("Preparing %zu update commands", num_cmds);
 694
 695         /* Make a copy of the update commands, in the process doing certain
 696          * canonicalizations on paths (e.g. translating backslashes to forward
 697          * slashes).  This is done to avoid modifying the caller's copy of the
 698          * commands. */
 699         ret = copy_update_commands(cmds, num_cmds, &cmds_copy);
 700         if (ret)
 701                 goto out;
 702
 703         /* Perform additional checks on the update commands before we execute
 704          * them. */
 705         ret = check_update_commands(cmds_copy, num_cmds, &wim->hdr);
 706         if (ret)
 707                 goto out_free_cmds_copy;
 708
 709         /* Actually execute the update commands. */
 710         DEBUG("Executing %zu update commands", num_cmds);
 711         ret = execute_update_commands(wim, cmds_copy, num_cmds, progress_func);
 712         if (ret)
 713                 goto out_free_cmds_copy;
 714
 715         wim->image_metadata[image - 1]->modified = 1;
 716
 717         /* Statistics about the WIM image, such as the numbers of files and
 718          * directories, may have changed.  Call xml_update_image_info() to
 719          * recalculate these statistics. */
 720         xml_update_image_info(wim, image);
 721 out_free_cmds_copy:
 722         free_update_commands(cmds_copy, num_cmds);
 723 out:
 724         return ret;
 725 }