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   1 /*
   2  * dentry.c
   3  *
   4  * In the WIM file format, the dentries are stored in the "metadata resource"
   5  * section right after the security data.  Each image in the WIM file has its
   6  * own metadata resource with its own security data and dentry tree.  Dentries
   7  * in different images may share file resources by referring to the same lookup
   8  * table entries.
   9  */
  10
  11 /*
  12  * Copyright (C) 2012, 2013 Eric Biggers
  13  *
  14  * This file is part of wimlib, a library for working with WIM files.
  15  *
  16  * wimlib is free software; you can redistribute it and/or modify it under the
  17  * terms of the GNU General Public License as published by the Free Software
  18  * Foundation; either version 3 of the License, or (at your option) any later
  19  * version.
  20  *
  21  * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY
  22  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
  23  * A PARTICULAR PURPOSE. See the GNU General Public License for more details.
  24  *
  25  * You should have received a copy of the GNU General Public License along with
  26  * wimlib; if not, see http://www.gnu.org/licenses/.
  27  */
  28
  29 #include "buffer_io.h"
  30 #include "dentry.h"
  31 #include "lookup_table.h"
  32 #include "timestamp.h"
  33 #include "wimlib_internal.h"
  34 #include <errno.h>
  35
  36 /* Calculates the unaligned length, in bytes, of an on-disk WIM dentry that has
  37  * a file name and short name that take the specified numbers of bytes.  This
  38  * excludes any alternate data stream entries that may follow the dentry. */
  39 static u64
  40 __dentry_correct_length_unaligned(u16 file_name_nbytes, u16 short_name_nbytes)
  41 {
  42         u64 length = WIM_DENTRY_DISK_SIZE;
  43         if (file_name_nbytes)
  44                 length += file_name_nbytes + 2;
  45         if (short_name_nbytes)
  46                 length += short_name_nbytes + 2;
  47         return length;
  48 }
  49
  50 /* Calculates the unaligned length, in bytes, of an on-disk WIM dentry, based on
  51  * the file name length and short name length.  Note that dentry->length is
  52  * ignored; also, this excludes any alternate data stream entries that may
  53  * follow the dentry. */
  54 static u64
  55 dentry_correct_length_unaligned(const struct wim_dentry *dentry)
  56 {
  57         return __dentry_correct_length_unaligned(dentry->file_name_nbytes,
  58                                                  dentry->short_name_nbytes);
  59 }
  60
  61 /* Return the "correct" value to write in the length field of a WIM dentry,
  62  * based on the file name length and short name length. */
  63 static u64
  64 dentry_correct_length(const struct wim_dentry *dentry)
  65 {
  66         return (dentry_correct_length_unaligned(dentry) + 7) & ~7;
  67 }
  68
  69 /* Return %true iff the alternate data stream entry @entry has the UTF-16LE
  70  * stream name @name that has length @name_nbytes bytes. */
  71 static inline bool
  72 ads_entry_has_name(const struct wim_ads_entry *entry,
  73                    const utf16lechar *name, size_t name_nbytes)
  74 {
  75         return entry->stream_name_nbytes == name_nbytes &&
  76                memcmp(entry->stream_name, name, name_nbytes) == 0;
  77 }
  78
  79 /* Duplicates a string of system-dependent encoding into a UTF-16LE string and
  80  * returns the string and its length, in bytes, in the pointer arguments.  Frees
  81  * any existing string at the return location before overwriting it. */
  82 static int
  83 get_utf16le_name(const tchar *name, utf16lechar **name_utf16le_ret,
  84                  u16 *name_utf16le_nbytes_ret)
  85 {
  86         utf16lechar *name_utf16le;
  87         size_t name_utf16le_nbytes;
  88         int ret;
  89 #if TCHAR_IS_UTF16LE
  90         name_utf16le_nbytes = tstrlen(name) * sizeof(utf16lechar);
  91         name_utf16le = MALLOC(name_utf16le_nbytes + sizeof(utf16lechar));
  92         if (!name_utf16le)
  93                 return WIMLIB_ERR_NOMEM;
  94         memcpy(name_utf16le, name, name_utf16le_nbytes + sizeof(utf16lechar));
  95         ret = 0;
  96 #else
  97
  98         ret = tstr_to_utf16le(name, tstrlen(name), &name_utf16le,
  99                               &name_utf16le_nbytes);
 100         if (ret == 0) {
 101                 if (name_utf16le_nbytes > 0xffff) {
 102                         FREE(name_utf16le);
 103                         ERROR("Multibyte string \"%"TS"\" is too long!", name);
 104                         ret = WIMLIB_ERR_INVALID_UTF8_STRING;
 105                 }
 106         }
 107 #endif
 108         if (ret == 0) {
 109                 FREE(*name_utf16le_ret);
 110                 *name_utf16le_ret = name_utf16le;
 111                 *name_utf16le_nbytes_ret = name_utf16le_nbytes;
 112         }
 113         return ret;
 114 }
 115
 116 /* Sets the name of a WIM dentry from a multibyte string. */
 117 int
 118 set_dentry_name(struct wim_dentry *dentry, const tchar *new_name)
 119 {
 120         int ret;
 121         ret = get_utf16le_name(new_name, &dentry->file_name,
 122                                &dentry->file_name_nbytes);
 123         if (ret == 0) {
 124                 /* Clear the short name and recalculate the dentry length */
 125                 if (dentry_has_short_name(dentry)) {
 126                         FREE(dentry->short_name);
 127                         dentry->short_name = NULL;
 128                         dentry->short_name_nbytes = 0;
 129                 }
 130                 dentry->length = dentry_correct_length(dentry);
 131         }
 132         return ret;
 133 }
 134
 135 /* Returns the total length of a WIM alternate data stream entry on-disk,
 136  * including the stream name, the null terminator, AND the padding after the
 137  * entry to align the next ADS entry or dentry on an 8-byte boundary. */
 138 static u64
 139 ads_entry_total_length(const struct wim_ads_entry *entry)
 140 {
 141         u64 len = WIM_ADS_ENTRY_DISK_SIZE;
 142         if (entry->stream_name_nbytes)
 143                 len += entry->stream_name_nbytes + 2;
 144         return (len + 7) & ~7;
 145 }
 146
 147
 148 static u64
 149 __dentry_total_length(const struct wim_dentry *dentry, u64 length)
 150 {
 151         const struct wim_inode *inode = dentry->d_inode;
 152         for (u16 i = 0; i < inode->i_num_ads; i++)
 153                 length += ads_entry_total_length(&inode->i_ads_entries[i]);
 154         return (length + 7) & ~7;
 155 }
 156
 157 /* Calculate the aligned *total* length of an on-disk WIM dentry.  This includes
 158  * all alternate data streams. */
 159 u64
 160 dentry_correct_total_length(const struct wim_dentry *dentry)
 161 {
 162         return __dentry_total_length(dentry,
 163                                      dentry_correct_length_unaligned(dentry));
 164 }
 165
 166 /* Like dentry_correct_total_length(), but use the existing dentry->length field
 167  * instead of calculating its "correct" value. */
 168 static u64
 169 dentry_total_length(const struct wim_dentry *dentry)
 170 {
 171         return __dentry_total_length(dentry, dentry->length);
 172 }
 173
 174 int
 175 for_dentry_in_rbtree(struct rb_node *root,
 176                      int (*visitor)(struct wim_dentry *, void *),
 177                      void *arg)
 178 {
 179         int ret;
 180         struct rb_node *node = root;
 181         LIST_HEAD(stack);
 182         while (1) {
 183                 if (node) {
 184                         list_add(&rbnode_dentry(node)->tmp_list, &stack);
 185                         node = node->rb_left;
 186                 } else {
 187                         struct list_head *next;
 188                         struct wim_dentry *dentry;
 189
 190                         next = stack.next;
 191                         if (next == &stack)
 192                                 return 0;
 193                         dentry = container_of(next, struct wim_dentry, tmp_list);
 194                         list_del(next);
 195                         ret = visitor(dentry, arg);
 196                         if (ret != 0)
 197                                 return ret;
 198                         node = dentry->rb_node.rb_right;
 199                 }
 200         }
 201 }
 202
 203 static int
 204 for_dentry_tree_in_rbtree_depth(struct rb_node *node,
 205                                 int (*visitor)(struct wim_dentry*, void*),
 206                                 void *arg)
 207 {
 208         int ret;
 209         if (node) {
 210                 ret = for_dentry_tree_in_rbtree_depth(node->rb_left,
 211                                                       visitor, arg);
 212                 if (ret != 0)
 213                         return ret;
 214                 ret = for_dentry_tree_in_rbtree_depth(node->rb_right,
 215                                                       visitor, arg);
 216                 if (ret != 0)
 217                         return ret;
 218                 ret = for_dentry_in_tree_depth(rbnode_dentry(node), visitor, arg);
 219                 if (ret != 0)
 220                         return ret;
 221         }
 222         return 0;
 223 }
 224
 225 static int
 226 for_dentry_tree_in_rbtree(struct rb_node *node,
 227                           int (*visitor)(struct wim_dentry*, void*),
 228                           void *arg)
 229 {
 230         int ret;
 231         if (node) {
 232                 ret = for_dentry_tree_in_rbtree(node->rb_left, visitor, arg);
 233                 if (ret != 0)
 234                         return ret;
 235                 ret = for_dentry_in_tree(rbnode_dentry(node), visitor, arg);
 236                 if (ret != 0)
 237                         return ret;
 238                 ret = for_dentry_tree_in_rbtree(node->rb_right, visitor, arg);
 239                 if (ret != 0)
 240                         return ret;
 241         }
 242         return 0;
 243 }
 244
 245 /* Calls a function on all directory entries in a WIM dentry tree.  Logically,
 246  * this is a pre-order traversal (the function is called on a parent dentry
 247  * before its children), but sibling dentries will be visited in order as well.
 248  * */
 249 int
 250 for_dentry_in_tree(struct wim_dentry *root,
 251                    int (*visitor)(struct wim_dentry*, void*), void *arg)
 252 {
 253         int ret = visitor(root, arg);
 254         if (ret == 0) {
 255                 ret = for_dentry_tree_in_rbtree(root->d_inode->i_children.rb_node,
 256                                                 visitor,
 257                                                 arg);
 258         }
 259         return ret;
 260 }
 261
 262 /* Like for_dentry_in_tree(), but the visitor function is always called on a
 263  * dentry's children before on itself. */
 264 int
 265 for_dentry_in_tree_depth(struct wim_dentry *root,
 266                          int (*visitor)(struct wim_dentry*, void*), void *arg)
 267 {
 268         int ret;
 269         ret = for_dentry_tree_in_rbtree_depth(root->d_inode->i_children.rb_node,
 270                                               visitor, arg);
 271         if (ret == 0)
 272                 ret = visitor(root, arg);
 273         return ret;
 274 }
 275
 276 /* Calculate the full path of @dentry.  The full path of its parent must have
 277  * already been calculated, or it must be the root dentry. */
 278 static int
 279 calculate_dentry_full_path(struct wim_dentry *dentry)
 280 {
 281         tchar *full_path;
 282         u32 full_path_nbytes;
 283         int ret;
 284
 285         if (dentry->_full_path)
 286                 return 0;
 287
 288         if (dentry_is_root(dentry)) {
 289                 full_path = TSTRDUP(T("/"));
 290                 if (!full_path)
 291                         return WIMLIB_ERR_NOMEM;
 292                 full_path_nbytes = 1 * sizeof(tchar);
 293         } else {
 294                 struct wim_dentry *parent;
 295                 tchar *parent_full_path;
 296                 u32 parent_full_path_nbytes;
 297                 size_t filename_nbytes;
 298
 299                 parent = dentry->parent;
 300                 if (dentry_is_root(parent)) {
 301                         parent_full_path = T("");
 302                         parent_full_path_nbytes = 0;
 303                 } else {
 304                         if (!parent->_full_path) {
 305                                 ret = calculate_dentry_full_path(parent);
 306                                 if (ret)
 307                                         return ret;
 308                         }
 309                         parent_full_path = parent->_full_path;
 310                         parent_full_path_nbytes = parent->full_path_nbytes;
 311                 }
 312
 313                 /* Append this dentry's name as a tchar string to the full path
 314                  * of the parent followed by the path separator */
 315         #if TCHAR_IS_UTF16LE
 316                 filename_nbytes = dentry->file_name_nbytes;
 317         #else
 318                 {
 319                         int ret = utf16le_to_tstr_nbytes(dentry->file_name,
 320                                                          dentry->file_name_nbytes,
 321                                                          &filename_nbytes);
 322                         if (ret)
 323                                 return ret;
 324                 }
 325         #endif
 326
 327                 full_path_nbytes = parent_full_path_nbytes + sizeof(tchar) +
 328                                    filename_nbytes;
 329                 full_path = MALLOC(full_path_nbytes + sizeof(tchar));
 330                 if (!full_path)
 331                         return WIMLIB_ERR_NOMEM;
 332                 memcpy(full_path, parent_full_path, parent_full_path_nbytes);
 333                 full_path[parent_full_path_nbytes / sizeof(tchar)] = T('/');
 334         #if TCHAR_IS_UTF16LE
 335                 memcpy(&full_path[parent_full_path_nbytes / sizeof(tchar) + 1],
 336                        dentry->file_name,
 337                        filename_nbytes + sizeof(tchar));
 338         #else
 339                 utf16le_to_tstr_buf(dentry->file_name,
 340                                     dentry->file_name_nbytes,
 341                                     &full_path[parent_full_path_nbytes /
 342                                                sizeof(tchar) + 1]);
 343         #endif
 344         }
 345         dentry->_full_path = full_path;
 346         dentry->full_path_nbytes= full_path_nbytes;
 347         return 0;
 348 }
 349
 350 static int
 351 do_calculate_dentry_full_path(struct wim_dentry *dentry, void *_ignore)
 352 {
 353         return calculate_dentry_full_path(dentry);
 354 }
 355
 356 int
 357 calculate_dentry_tree_full_paths(struct wim_dentry *root)
 358 {
 359         return for_dentry_in_tree(root, do_calculate_dentry_full_path, NULL);
 360 }
 361
 362 tchar *
 363 dentry_full_path(struct wim_dentry *dentry)
 364 {
 365         calculate_dentry_full_path(dentry);
 366         return dentry->_full_path;
 367 }
 368
 369 static int
 370 increment_subdir_offset(struct wim_dentry *dentry, void *subdir_offset_p)
 371 {
 372         *(u64*)subdir_offset_p += dentry_correct_total_length(dentry);
 373         return 0;
 374 }
 375
 376 static int
 377 call_calculate_subdir_offsets(struct wim_dentry *dentry, void *subdir_offset_p)
 378 {
 379         calculate_subdir_offsets(dentry, subdir_offset_p);
 380         return 0;
 381 }
 382
 383 /*
 384  * Recursively calculates the subdir offsets for a directory tree.
 385  *
 386  * @dentry:  The root of the directory tree.
 387  * @subdir_offset_p:  The current subdirectory offset; i.e., the subdirectory
 388  *                    offset for @dentry.
 389  */
 390 void
 391 calculate_subdir_offsets(struct wim_dentry *dentry, u64 *subdir_offset_p)
 392 {
 393         struct rb_node *node;
 394
 395         dentry->subdir_offset = *subdir_offset_p;
 396         node = dentry->d_inode->i_children.rb_node;
 397         if (node) {
 398                 /* Advance the subdir offset by the amount of space the children
 399                  * of this dentry take up. */
 400                 for_dentry_in_rbtree(node, increment_subdir_offset, subdir_offset_p);
 401
 402                 /* End-of-directory dentry on disk. */
 403                 *subdir_offset_p += 8;
 404
 405                 /* Recursively call calculate_subdir_offsets() on all the
 406                  * children. */
 407                 for_dentry_in_rbtree(node, call_calculate_subdir_offsets, subdir_offset_p);
 408         } else {
 409                 /* On disk, childless directories have a valid subdir_offset
 410                  * that points to an 8-byte end-of-directory dentry.  Regular
 411                  * files or reparse points have a subdir_offset of 0. */
 412                 if (dentry_is_directory(dentry))
 413                         *subdir_offset_p += 8;
 414                 else
 415                         dentry->subdir_offset = 0;
 416         }
 417 }
 418
 419 static int
 420 compare_utf16le_names(const utf16lechar *name1, size_t nbytes1,
 421                       const utf16lechar *name2, size_t nbytes2)
 422 {
 423         int result = memcmp(name1, name2, min(nbytes1, nbytes2));
 424         if (result)
 425                 return result;
 426         else
 427                 return (int)nbytes1 - (int)nbytes2;
 428 }
 429
 430 static int
 431 dentry_compare_names(const struct wim_dentry *d1, const struct wim_dentry *d2)
 432 {
 433         return compare_utf16le_names(d1->file_name, d1->file_name_nbytes,
 434                                      d2->file_name, d2->file_name_nbytes);
 435 }
 436
 437
 438 struct wim_dentry *
 439 get_dentry_child_with_utf16le_name(const struct wim_dentry *dentry,
 440                                    const utf16lechar *name,
 441                                    size_t name_nbytes)
 442 {
 443         struct rb_node *node = dentry->d_inode->i_children.rb_node;
 444         struct wim_dentry *child;
 445         while (node) {
 446                 child = rbnode_dentry(node);
 447                 int result = compare_utf16le_names(name, name_nbytes,
 448                                                    child->file_name,
 449                                                    child->file_name_nbytes);
 450                 if (result < 0)
 451                         node = node->rb_left;
 452                 else if (result > 0)
 453                         node = node->rb_right;
 454                 else
 455                         return child;
 456         }
 457         return NULL;
 458 }
 459
 460 /* Returns the child of @dentry that has the file name @name.  Returns NULL if
 461  * no child has the name. */
 462 struct wim_dentry *
 463 get_dentry_child_with_name(const struct wim_dentry *dentry, const tchar *name)
 464 {
 465 #if TCHAR_IS_UTF16LE
 466         return get_dentry_child_with_utf16le_name(dentry, name,
 467                                                   tstrlen(name) * sizeof(tchar));
 468 #else
 469         utf16lechar *utf16le_name;
 470         size_t utf16le_name_nbytes;
 471         int ret;
 472         struct wim_dentry *child;
 473
 474         ret = tstr_to_utf16le(name, tstrlen(name) * sizeof(tchar),
 475                               &utf16le_name, &utf16le_name_nbytes);
 476         if (ret) {
 477                 child = NULL;
 478         } else {
 479                 child = get_dentry_child_with_utf16le_name(dentry,
 480                                                            utf16le_name,
 481                                                            utf16le_name_nbytes);
 482                 FREE(utf16le_name);
 483         }
 484         return child;
 485 #endif
 486 }
 487
 488 static struct wim_dentry *
 489 get_dentry_utf16le(WIMStruct *w, const utf16lechar *path,
 490                    size_t path_nbytes)
 491 {
 492         struct wim_dentry *cur_dentry, *parent_dentry;
 493         const utf16lechar *p, *pp;
 494
 495         cur_dentry = parent_dentry = wim_root_dentry(w);
 496         p = path;
 497         while (1) {
 498                 while (*p == cpu_to_le16('/'))
 499                         p++;
 500                 if (*p == '\0')
 501                         break;
 502                 pp = p;
 503                 while (*pp != cpu_to_le16('/') && *pp != cpu_to_le16('\0'))
 504                         pp++;
 505
 506                 cur_dentry = get_dentry_child_with_utf16le_name(parent_dentry, p,
 507                                                                 (void*)pp - (void*)p);
 508                 if (cur_dentry == NULL)
 509                         break;
 510                 p = pp;
 511                 parent_dentry = cur_dentry;
 512         }
 513         if (cur_dentry == NULL) {
 514                 if (dentry_is_directory(parent_dentry))
 515                         errno = ENOENT;
 516                 else
 517                         errno = ENOTDIR;
 518         }
 519         return cur_dentry;
 520 }
 521
 522 /* Returns the dentry corresponding to the @path, or NULL if there is no such
 523  * dentry. */
 524 struct wim_dentry *
 525 get_dentry(WIMStruct *w, const tchar *path)
 526 {
 527 #if TCHAR_IS_UTF16LE
 528         return get_dentry_utf16le(w, path, tstrlen(path) * sizeof(tchar));
 529 #else
 530         utf16lechar *path_utf16le;
 531         size_t path_utf16le_nbytes;
 532         int ret;
 533         struct wim_dentry *dentry;
 534
 535         ret = tstr_to_utf16le(path, tstrlen(path) * sizeof(tchar),
 536                               &path_utf16le, &path_utf16le_nbytes);
 537         if (ret)
 538                 return NULL;
 539         dentry = get_dentry_utf16le(w, path_utf16le, path_utf16le_nbytes);
 540         FREE(path_utf16le);
 541         return dentry;
 542 #endif
 543 }
 544
 545 struct wim_inode *
 546 wim_pathname_to_inode(WIMStruct *w, const tchar *path)
 547 {
 548         struct wim_dentry *dentry;
 549         dentry = get_dentry(w, path);
 550         if (dentry)
 551                 return dentry->d_inode;
 552         else
 553                 return NULL;
 554 }
 555
 556 /* Takes in a path of length @len in @buf, and transforms it into a string for
 557  * the path of its parent directory. */
 558 static void
 559 to_parent_name(tchar *buf, size_t len)
 560 {
 561         ssize_t i = (ssize_t)len - 1;
 562         while (i >= 0 && buf[i] == T('/'))
 563                 i--;
 564         while (i >= 0 && buf[i] != T('/'))
 565                 i--;
 566         while (i >= 0 && buf[i] == T('/'))
 567                 i--;
 568         buf[i + 1] = T('\0');
 569 }
 570
 571 /* Returns the dentry that corresponds to the parent directory of @path, or NULL
 572  * if the dentry is not found. */
 573 struct wim_dentry *
 574 get_parent_dentry(WIMStruct *w, const tchar *path)
 575 {
 576         size_t path_len = tstrlen(path);
 577         tchar buf[path_len + 1];
 578
 579         tmemcpy(buf, path, path_len + 1);
 580         to_parent_name(buf, path_len);
 581         return get_dentry(w, buf);
 582 }
 583
 584 /* Prints the full path of a dentry. */
 585 int
 586 print_dentry_full_path(struct wim_dentry *dentry, void *_ignore)
 587 {
 588         int ret = calculate_dentry_full_path(dentry);
 589         if (ret)
 590                 return ret;
 591         tprintf(T("%"TS"\n"), dentry->_full_path);
 592         return 0;
 593 }
 594
 595 /* We want to be able to show the names of the file attribute flags that are
 596  * set. */
 597 struct file_attr_flag {
 598         u32 flag;
 599         const tchar *name;
 600 };
 601 struct file_attr_flag file_attr_flags[] = {
 602         {FILE_ATTRIBUTE_READONLY,           T("READONLY")},
 603         {FILE_ATTRIBUTE_HIDDEN,             T("HIDDEN")},
 604         {FILE_ATTRIBUTE_SYSTEM,             T("SYSTEM")},
 605         {FILE_ATTRIBUTE_DIRECTORY,          T("DIRECTORY")},
 606         {FILE_ATTRIBUTE_ARCHIVE,            T("ARCHIVE")},
 607         {FILE_ATTRIBUTE_DEVICE,             T("DEVICE")},
 608         {FILE_ATTRIBUTE_NORMAL,             T("NORMAL")},
 609         {FILE_ATTRIBUTE_TEMPORARY,          T("TEMPORARY")},
 610         {FILE_ATTRIBUTE_SPARSE_FILE,        T("SPARSE_FILE")},
 611         {FILE_ATTRIBUTE_REPARSE_POINT,      T("REPARSE_POINT")},
 612         {FILE_ATTRIBUTE_COMPRESSED,         T("COMPRESSED")},
 613         {FILE_ATTRIBUTE_OFFLINE,            T("OFFLINE")},
 614         {FILE_ATTRIBUTE_NOT_CONTENT_INDEXED,T("NOT_CONTENT_INDEXED")},
 615         {FILE_ATTRIBUTE_ENCRYPTED,          T("ENCRYPTED")},
 616         {FILE_ATTRIBUTE_VIRTUAL,            T("VIRTUAL")},
 617 };
 618
 619 /* Prints a directory entry.  @lookup_table is a pointer to the lookup table, if
 620  * available.  If the dentry is unresolved and the lookup table is NULL, the
 621  * lookup table entries will not be printed.  Otherwise, they will be. */
 622 int
 623 print_dentry(struct wim_dentry *dentry, void *lookup_table)
 624 {
 625         const u8 *hash;
 626         struct wim_lookup_table_entry *lte;
 627         const struct wim_inode *inode = dentry->d_inode;
 628         tchar buf[50];
 629
 630         tprintf(T("[DENTRY]\n"));
 631         tprintf(T("Length            = %"PRIu64"\n"), dentry->length);
 632         tprintf(T("Attributes        = 0x%x\n"), inode->i_attributes);
 633         for (size_t i = 0; i < ARRAY_LEN(file_attr_flags); i++)
 634                 if (file_attr_flags[i].flag & inode->i_attributes)
 635                         tprintf(T("    FILE_ATTRIBUTE_%"TS" is set\n"),
 636                                 file_attr_flags[i].name);
 637         tprintf(T("Security ID       = %d\n"), inode->i_security_id);
 638         tprintf(T("Subdir offset     = %"PRIu64"\n"), dentry->subdir_offset);
 639
 640         wim_timestamp_to_str(inode->i_creation_time, buf, sizeof(buf));
 641         tprintf(T("Creation Time     = %"TS"\n"), buf);
 642
 643         wim_timestamp_to_str(inode->i_last_access_time, buf, sizeof(buf));
 644         tprintf(T("Last Access Time  = %"TS"\n"), buf);
 645
 646         wim_timestamp_to_str(inode->i_last_write_time, buf, sizeof(buf));
 647         tprintf(T("Last Write Time   = %"TS"\n"), buf);
 648
 649         if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
 650                 tprintf(T("Reparse Tag       = 0x%"PRIx32"\n"), inode->i_reparse_tag);
 651                 tprintf(T("Reparse Point Flags = 0x%"PRIx16"\n"),
 652                         inode->i_not_rpfixed);
 653                 tprintf(T("Reparse Point Unknown 2 = 0x%"PRIx32"\n"),
 654                         inode->i_rp_unknown_2);
 655         }
 656         tprintf(T("Reparse Point Unknown 1 = 0x%"PRIx32"\n"),
 657                 inode->i_rp_unknown_1);
 658         tprintf(T("Hard Link Group   = 0x%"PRIx64"\n"), inode->i_ino);
 659         tprintf(T("Hard Link Group Size = %"PRIu32"\n"), inode->i_nlink);
 660         tprintf(T("Number of Alternate Data Streams = %hu\n"), inode->i_num_ads);
 661         if (dentry_has_long_name(dentry))
 662                 wimlib_printf(T("Filename = \"%"WS"\"\n"), dentry->file_name);
 663         if (dentry_has_short_name(dentry))
 664                 wimlib_printf(T("Short Name \"%"WS"\"\n"), dentry->short_name);
 665         if (dentry->_full_path)
 666                 tprintf(T("Full Path = \"%"TS"\"\n"), dentry->_full_path);
 667
 668         lte = inode_stream_lte(dentry->d_inode, 0, lookup_table);
 669         if (lte) {
 670                 print_lookup_table_entry(lte, stdout);
 671         } else {
 672                 hash = inode_stream_hash(inode, 0);
 673                 if (hash) {
 674                         tprintf(T("Hash              = 0x"));
 675                         print_hash(hash, stdout);
 676                         tputchar(T('\n'));
 677                         tputchar(T('\n'));
 678                 }
 679         }
 680         for (u16 i = 0; i < inode->i_num_ads; i++) {
 681                 tprintf(T("[Alternate Stream Entry %u]\n"), i);
 682                 wimlib_printf(T("Name = \"%"WS"\"\n"),
 683                               inode->i_ads_entries[i].stream_name);
 684                 tprintf(T("Name Length (UTF16 bytes) = %hu\n"),
 685                        inode->i_ads_entries[i].stream_name_nbytes);
 686                 hash = inode_stream_hash(inode, i + 1);
 687                 if (hash) {
 688                         tprintf(T("Hash              = 0x"));
 689                         print_hash(hash, stdout);
 690                         tputchar(T('\n'));
 691                 }
 692                 print_lookup_table_entry(inode_stream_lte(inode, i + 1, lookup_table),
 693                                          stdout);
 694         }
 695         return 0;
 696 }
 697
 698 /* Initializations done on every `struct wim_dentry'. */
 699 static void
 700 dentry_common_init(struct wim_dentry *dentry)
 701 {
 702         memset(dentry, 0, sizeof(struct wim_dentry));
 703 }
 704
 705 struct wim_inode *
 706 new_timeless_inode()
 707 {
 708         struct wim_inode *inode = CALLOC(1, sizeof(struct wim_inode));
 709         if (inode) {
 710                 inode->i_security_id = -1;
 711                 inode->i_nlink = 1;
 712                 inode->i_next_stream_id = 1;
 713                 inode->i_not_rpfixed = 1;
 714                 INIT_LIST_HEAD(&inode->i_list);
 715         #ifdef WITH_FUSE
 716                 if (pthread_mutex_init(&inode->i_mutex, NULL) != 0) {
 717                         ERROR_WITH_ERRNO("Error initializing mutex");
 718                         FREE(inode);
 719                         return NULL;
 720                 }
 721         #endif
 722                 INIT_LIST_HEAD(&inode->i_dentry);
 723         }
 724         return inode;
 725 }
 726
 727 static struct wim_inode *
 728 new_inode()
 729 {
 730         struct wim_inode *inode = new_timeless_inode();
 731         if (inode) {
 732                 u64 now = get_wim_timestamp();
 733                 inode->i_creation_time = now;
 734                 inode->i_last_access_time = now;
 735                 inode->i_last_write_time = now;
 736         }
 737         return inode;
 738 }
 739
 740 /* Creates an unlinked directory entry. */
 741 int
 742 new_dentry(const tchar *name, struct wim_dentry **dentry_ret)
 743 {
 744         struct wim_dentry *dentry;
 745         int ret;
 746
 747         dentry = MALLOC(sizeof(struct wim_dentry));
 748         if (!dentry)
 749                 return WIMLIB_ERR_NOMEM;
 750
 751         dentry_common_init(dentry);
 752         ret = set_dentry_name(dentry, name);
 753         if (ret == 0) {
 754                 dentry->parent = dentry;
 755                 *dentry_ret = dentry;
 756         } else {
 757                 FREE(dentry);
 758                 ERROR("Failed to set name on new dentry with name \"%"TS"\"",
 759                       name);
 760         }
 761         return ret;
 762 }
 763
 764
 765 static int
 766 __new_dentry_with_inode(const tchar *name, struct wim_dentry **dentry_ret,
 767                         bool timeless)
 768 {
 769         struct wim_dentry *dentry;
 770         int ret;
 771
 772         ret = new_dentry(name, &dentry);
 773         if (ret)
 774                 return ret;
 775
 776         if (timeless)
 777                 dentry->d_inode = new_timeless_inode();
 778         else
 779                 dentry->d_inode = new_inode();
 780         if (!dentry->d_inode) {
 781                 free_dentry(dentry);
 782                 return WIMLIB_ERR_NOMEM;
 783         }
 784
 785         inode_add_dentry(dentry, dentry->d_inode);
 786         *dentry_ret = dentry;
 787         return 0;
 788 }
 789
 790 int
 791 new_dentry_with_timeless_inode(const tchar *name, struct wim_dentry **dentry_ret)
 792 {
 793         return __new_dentry_with_inode(name, dentry_ret, true);
 794 }
 795
 796 int
 797 new_dentry_with_inode(const tchar *name, struct wim_dentry **dentry_ret)
 798 {
 799         return __new_dentry_with_inode(name, dentry_ret, false);
 800 }
 801
 802
 803 static int
 804 init_ads_entry(struct wim_ads_entry *ads_entry, const void *name,
 805                size_t name_nbytes, bool is_utf16le)
 806 {
 807         int ret = 0;
 808         memset(ads_entry, 0, sizeof(*ads_entry));
 809
 810         if (is_utf16le) {
 811                 utf16lechar *p = MALLOC(name_nbytes + sizeof(utf16lechar));
 812                 if (!p)
 813                         return WIMLIB_ERR_NOMEM;
 814                 memcpy(p, name, name_nbytes);
 815                 p[name_nbytes / 2] = 0;
 816                 ads_entry->stream_name = p;
 817                 ads_entry->stream_name_nbytes = name_nbytes;
 818         } else {
 819                 if (name && *(const tchar*)name != T('\0')) {
 820                         ret = get_utf16le_name(name, &ads_entry->stream_name,
 821                                                &ads_entry->stream_name_nbytes);
 822                 }
 823         }
 824         return ret;
 825 }
 826
 827 static void
 828 destroy_ads_entry(struct wim_ads_entry *ads_entry)
 829 {
 830         FREE(ads_entry->stream_name);
 831 }
 832
 833 /* Frees an inode. */
 834 void
 835 free_inode(struct wim_inode *inode)
 836 {
 837         if (inode) {
 838                 if (inode->i_ads_entries) {
 839                         for (u16 i = 0; i < inode->i_num_ads; i++)
 840                                 destroy_ads_entry(&inode->i_ads_entries[i]);
 841                         FREE(inode->i_ads_entries);
 842                 }
 843         #ifdef WITH_FUSE
 844                 wimlib_assert(inode->i_num_opened_fds == 0);
 845                 FREE(inode->i_fds);
 846                 pthread_mutex_destroy(&inode->i_mutex);
 847         #endif
 848                 /* HACK: This may instead delete the inode from i_list, but the
 849                  * hlist_del() behaves the same as list_del(). */
 850                 hlist_del(&inode->i_hlist);
 851                 FREE(inode->i_extracted_file);
 852                 FREE(inode);
 853         }
 854 }
 855
 856 /* Decrements link count on an inode and frees it if the link count reaches 0.
 857  * */
 858 static void
 859 put_inode(struct wim_inode *inode)
 860 {
 861         wimlib_assert(inode->i_nlink != 0);
 862         if (--inode->i_nlink == 0) {
 863         #ifdef WITH_FUSE
 864                 if (inode->i_num_opened_fds == 0)
 865         #endif
 866                 {
 867                         free_inode(inode);
 868                 }
 869         }
 870 }
 871
 872 /* Frees a WIM dentry.
 873  *
 874  * The corresponding inode (if any) is freed only if its link count is
 875  * decremented to 0.
 876  */
 877 void
 878 free_dentry(struct wim_dentry *dentry)
 879 {
 880         FREE(dentry->file_name);
 881         FREE(dentry->short_name);
 882         FREE(dentry->_full_path);
 883         if (dentry->d_inode)
 884                 put_inode(dentry->d_inode);
 885         FREE(dentry);
 886 }
 887
 888 /* This function is passed as an argument to for_dentry_in_tree_depth() in order
 889  * to free a directory tree. */
 890 static int
 891 do_free_dentry(struct wim_dentry *dentry, void *__lookup_table)
 892 {
 893         struct wim_lookup_table *lookup_table = __lookup_table;
 894         unsigned i;
 895
 896         if (lookup_table) {
 897                 struct wim_lookup_table_entry *lte;
 898                 struct wim_inode *inode = dentry->d_inode;
 899                 wimlib_assert(inode->i_nlink != 0);
 900                 for (i = 0; i <= inode->i_num_ads; i++) {
 901                         lte = inode_stream_lte(inode, i, lookup_table);
 902                         if (lte)
 903                                 lte_decrement_refcnt(lte, lookup_table);
 904                 }
 905         }
 906         free_dentry(dentry);
 907         return 0;
 908 }
 909
 910 /*
 911  * Unlinks and frees a dentry tree.
 912  *
 913  * @root:               The root of the tree.
 914  * @lookup_table:       The lookup table for dentries.  If non-NULL, the
 915  *                      reference counts in the lookup table for the lookup
 916  *                      table entries corresponding to the dentries will be
 917  *                      decremented.
 918  */
 919 void
 920 free_dentry_tree(struct wim_dentry *root, struct wim_lookup_table *lookup_table)
 921 {
 922         if (root)
 923                 for_dentry_in_tree_depth(root, do_free_dentry, lookup_table);
 924 }
 925
 926 /*
 927  * Links a dentry into the directory tree.
 928  *
 929  * @parent: The dentry that will be the parent of @dentry.
 930  * @dentry: The dentry to link.
 931  */
 932 struct wim_dentry *
 933 dentry_add_child(struct wim_dentry * restrict parent,
 934                  struct wim_dentry * restrict child)
 935 {
 936         wimlib_assert(dentry_is_directory(parent));
 937
 938         struct rb_root *root = &parent->d_inode->i_children;
 939         struct rb_node **new = &(root->rb_node);
 940         struct rb_node *rb_parent = NULL;
 941
 942         while (*new) {
 943                 struct wim_dentry *this = rbnode_dentry(*new);
 944                 int result = dentry_compare_names(child, this);
 945
 946                 rb_parent = *new;
 947
 948                 if (result < 0)
 949                         new = &((*new)->rb_left);
 950                 else if (result > 0)
 951                         new = &((*new)->rb_right);
 952                 else
 953                         return this;
 954         }
 955         child->parent = parent;
 956         rb_link_node(&child->rb_node, rb_parent, new);
 957         rb_insert_color(&child->rb_node, root);
 958         return NULL;
 959 }
 960
 961 /* Unlink a WIM dentry from the directory entry tree. */
 962 void
 963 unlink_dentry(struct wim_dentry *dentry)
 964 {
 965         struct wim_dentry *parent = dentry->parent;
 966         if (parent == dentry)
 967                 return;
 968         rb_erase(&dentry->rb_node, &parent->d_inode->i_children);
 969 }
 970
 971 /*
 972  * Returns the alternate data stream entry belonging to @inode that has the
 973  * stream name @stream_name.
 974  */
 975 struct wim_ads_entry *
 976 inode_get_ads_entry(struct wim_inode *inode, const tchar *stream_name,
 977                     u16 *idx_ret)
 978 {
 979         if (inode->i_num_ads == 0) {
 980                 return NULL;
 981         } else {
 982                 size_t stream_name_utf16le_nbytes;
 983                 u16 i;
 984                 struct wim_ads_entry *result;
 985
 986         #if TCHAR_IS_UTF16LE
 987                 const utf16lechar *stream_name_utf16le;
 988
 989                 stream_name_utf16le = stream_name;
 990                 stream_name_utf16le_nbytes = tstrlen(stream_name) * sizeof(tchar);
 991         #else
 992                 utf16lechar *stream_name_utf16le;
 993
 994                 {
 995                         int ret = tstr_to_utf16le(stream_name,
 996                                                   tstrlen(stream_name) *
 997                                                       sizeof(tchar),
 998                                                   &stream_name_utf16le,
 999                                                   &stream_name_utf16le_nbytes);
1000                         if (ret)
1001                                 return NULL;
1002                 }
1003         #endif
1004                 i = 0;
1005                 result = NULL;
1006                 do {
1007                         if (ads_entry_has_name(&inode->i_ads_entries[i],
1008                                                stream_name_utf16le,
1009                                                stream_name_utf16le_nbytes))
1010                         {
1011                                 if (idx_ret)
1012                                         *idx_ret = i;
1013                                 result = &inode->i_ads_entries[i];
1014                                 break;
1015                         }
1016                 } while (++i != inode->i_num_ads);
1017         #if !TCHAR_IS_UTF16LE
1018                 FREE(stream_name_utf16le);
1019         #endif
1020                 return result;
1021         }
1022 }
1023
1024 static struct wim_ads_entry *
1025 do_inode_add_ads(struct wim_inode *inode, const void *stream_name,
1026                  size_t stream_name_nbytes, bool is_utf16le)
1027 {
1028         u16 num_ads;
1029         struct wim_ads_entry *ads_entries;
1030         struct wim_ads_entry *new_entry;
1031
1032         if (inode->i_num_ads >= 0xfffe) {
1033                 ERROR("Too many alternate data streams in one inode!");
1034                 return NULL;
1035         }
1036         num_ads = inode->i_num_ads + 1;
1037         ads_entries = REALLOC(inode->i_ads_entries,
1038                               num_ads * sizeof(inode->i_ads_entries[0]));
1039         if (!ads_entries) {
1040                 ERROR("Failed to allocate memory for new alternate data stream");
1041                 return NULL;
1042         }
1043         inode->i_ads_entries = ads_entries;
1044
1045         new_entry = &inode->i_ads_entries[num_ads - 1];
1046         if (init_ads_entry(new_entry, stream_name, stream_name_nbytes, is_utf16le))
1047                 return NULL;
1048         new_entry->stream_id = inode->i_next_stream_id++;
1049         inode->i_num_ads = num_ads;
1050         return new_entry;
1051 }
1052
1053 struct wim_ads_entry *
1054 inode_add_ads_utf16le(struct wim_inode *inode,
1055                       const utf16lechar *stream_name,
1056                       size_t stream_name_nbytes)
1057 {
1058         DEBUG("Add alternate data stream \"%"WS"\"", stream_name);
1059         return do_inode_add_ads(inode, stream_name, stream_name_nbytes, true);
1060 }
1061
1062 /*
1063  * Add an alternate stream entry to a WIM inode and return a pointer to it, or
1064  * NULL if memory could not be allocated.
1065  */
1066 struct wim_ads_entry *
1067 inode_add_ads(struct wim_inode *inode, const tchar *stream_name)
1068 {
1069         DEBUG("Add alternate data stream \"%"TS"\"", stream_name);
1070         return do_inode_add_ads(inode, stream_name,
1071                                 tstrlen(stream_name) * sizeof(tchar),
1072                                 TCHAR_IS_UTF16LE);
1073 }
1074
1075 int
1076 inode_add_ads_with_data(struct wim_inode *inode, const tchar *name,
1077                         const void *value, size_t size,
1078                         struct wim_lookup_table *lookup_table)
1079 {
1080         int ret = WIMLIB_ERR_NOMEM;
1081         struct wim_ads_entry *new_ads_entry;
1082         struct wim_lookup_table_entry *existing_lte;
1083         struct wim_lookup_table_entry *lte;
1084         u8 value_hash[SHA1_HASH_SIZE];
1085
1086         wimlib_assert(inode->i_resolved);
1087         new_ads_entry = inode_add_ads(inode, name);
1088         if (!new_ads_entry)
1089                 goto out;
1090         sha1_buffer((const u8*)value, size, value_hash);
1091         existing_lte = __lookup_resource(lookup_table, value_hash);
1092         if (existing_lte) {
1093                 lte = existing_lte;
1094                 lte->refcnt++;
1095         } else {
1096                 u8 *value_copy;
1097                 lte = new_lookup_table_entry();
1098                 if (!lte)
1099                         goto out_remove_ads_entry;
1100                 value_copy = MALLOC(size);
1101                 if (!value_copy) {
1102                         FREE(lte);
1103                         goto out_remove_ads_entry;
1104                 }
1105                 memcpy(value_copy, value, size);
1106                 lte->resource_location            = RESOURCE_IN_ATTACHED_BUFFER;
1107                 lte->attached_buffer              = value_copy;
1108                 lte->resource_entry.original_size = size;
1109                 lte->resource_entry.size          = size;
1110                 copy_hash(lte->hash, value_hash);
1111                 lookup_table_insert(lookup_table, lte);
1112         }
1113         new_ads_entry->lte = lte;
1114         ret = 0;
1115         goto out;
1116 out_remove_ads_entry:
1117         inode_remove_ads(inode, new_ads_entry - inode->i_ads_entries,
1118                          lookup_table);
1119 out:
1120         return ret;
1121 }
1122
1123 /* Set the unnamed stream of a WIM inode, given a data buffer containing the
1124  * stream contents. */
1125 int
1126 inode_set_unnamed_stream(struct wim_inode *inode, const void *data, size_t len,
1127                          struct wim_lookup_table *lookup_table)
1128 {
1129         struct wim_lookup_table_entry *lte, *existing_lte;
1130         u8 hash[SHA1_HASH_SIZE];
1131         void *buf;
1132
1133         sha1_buffer(data, len, hash);
1134         existing_lte = __lookup_resource(lookup_table, hash);
1135         if (existing_lte) {
1136                 wimlib_assert(wim_resource_size(existing_lte) == len);
1137                 lte = existing_lte;
1138                 lte->refcnt++;
1139         } else {
1140                 lte = new_lookup_table_entry();
1141                 if (!lte)
1142                         return WIMLIB_ERR_NOMEM;
1143                 buf = MALLOC(len);
1144                 if (!buf) {
1145                         free_lookup_table_entry(lte);
1146                         return WIMLIB_ERR_NOMEM;
1147                 }
1148                 memcpy(buf, data, len);
1149                 lte->resource_location = RESOURCE_IN_ATTACHED_BUFFER;
1150                 lte->attached_buffer = buf;
1151                 lte->resource_entry.original_size = len;
1152                 copy_hash(lte->hash, hash);
1153                 lookup_table_insert(lookup_table, lte);
1154         }
1155         inode->i_lte = lte;
1156         inode->i_resolved = 1;
1157         return 0;
1158 }
1159
1160 /* Remove an alternate data stream from a WIM inode  */
1161 void
1162 inode_remove_ads(struct wim_inode *inode, u16 idx,
1163                  struct wim_lookup_table *lookup_table)
1164 {
1165         struct wim_ads_entry *ads_entry;
1166         struct wim_lookup_table_entry *lte;
1167
1168         wimlib_assert(idx < inode->i_num_ads);
1169         wimlib_assert(inode->i_resolved);
1170
1171         ads_entry = &inode->i_ads_entries[idx];
1172
1173         DEBUG("Remove alternate data stream \"%"WS"\"", ads_entry->stream_name);
1174
1175         lte = ads_entry->lte;
1176         if (lte)
1177                 lte_decrement_refcnt(lte, lookup_table);
1178
1179         destroy_ads_entry(ads_entry);
1180
1181         memmove(&inode->i_ads_entries[idx],
1182                 &inode->i_ads_entries[idx + 1],
1183                 (inode->i_num_ads - idx - 1) * sizeof(inode->i_ads_entries[0]));
1184         inode->i_num_ads--;
1185 }
1186
1187 #ifndef __WIN32__
1188 int
1189 inode_get_unix_data(const struct wim_inode *inode,
1190                     struct wimlib_unix_data *unix_data,
1191                     u16 *stream_idx_ret)
1192 {
1193         const struct wim_ads_entry *ads_entry;
1194         const struct wim_lookup_table_entry *lte;
1195         size_t size;
1196         int ret;
1197
1198         wimlib_assert(inode->i_resolved);
1199
1200         ads_entry = inode_get_ads_entry((struct wim_inode*)inode,
1201                                         WIMLIB_UNIX_DATA_TAG, NULL);
1202         if (!ads_entry)
1203                 return NO_UNIX_DATA;
1204
1205         if (stream_idx_ret)
1206                 *stream_idx_ret = ads_entry - inode->i_ads_entries;
1207
1208         lte = ads_entry->lte;
1209         if (!lte)
1210                 return NO_UNIX_DATA;
1211
1212         size = wim_resource_size(lte);
1213         if (size != sizeof(struct wimlib_unix_data))
1214                 return BAD_UNIX_DATA;
1215
1216         ret = read_full_resource_into_buf(lte, unix_data, true);
1217         if (ret)
1218                 return ret;
1219
1220         if (unix_data->version != 0)
1221                 return BAD_UNIX_DATA;
1222         return 0;
1223 }
1224
1225 int
1226 inode_set_unix_data(struct wim_inode *inode, uid_t uid, gid_t gid, mode_t mode,
1227                     struct wim_lookup_table *lookup_table, int which)
1228 {
1229         struct wimlib_unix_data unix_data;
1230         int ret;
1231         bool have_good_unix_data = false;
1232         bool have_unix_data = false;
1233         u16 stream_idx;
1234
1235         if (!(which & UNIX_DATA_CREATE)) {
1236                 ret = inode_get_unix_data(inode, &unix_data, &stream_idx);
1237                 if (ret == 0 || ret == BAD_UNIX_DATA || ret > 0)
1238                         have_unix_data = true;
1239                 if (ret == 0)
1240                         have_good_unix_data = true;
1241         }
1242         unix_data.version = 0;
1243         if (which & UNIX_DATA_UID || !have_good_unix_data)
1244                 unix_data.uid = uid;
1245         if (which & UNIX_DATA_GID || !have_good_unix_data)
1246                 unix_data.gid = gid;
1247         if (which & UNIX_DATA_MODE || !have_good_unix_data)
1248                 unix_data.mode = mode;
1249         ret = inode_add_ads_with_data(inode, WIMLIB_UNIX_DATA_TAG,
1250                                       &unix_data,
1251                                       sizeof(struct wimlib_unix_data),
1252                                       lookup_table);
1253         if (ret == 0 && have_unix_data)
1254                 inode_remove_ads(inode, stream_idx, lookup_table);
1255         return ret;
1256 }
1257 #endif /* !__WIN32__ */
1258
1259 /* Replace weird characters in filenames and alternate data stream names.
1260  *
1261  * In particular we do not want the path separator to appear in any names, as
1262  * that would make it possible for a "malicious" WIM to extract itself to any
1263  * location it wanted to. */
1264 static void
1265 replace_forbidden_characters(utf16lechar *name)
1266 {
1267         utf16lechar *p;
1268
1269         for (p = name; *p; p++) {
1270         #ifdef __WIN32__
1271                 if (wcschr(L"<>:\"/\\|?*", (wchar_t)*p))
1272         #else
1273                 if (*p == '/')
1274         #endif
1275                 {
1276                 #ifdef __WIN32__
1277                         *p = cpu_to_le16(0xfffd);
1278                 #else
1279                         *p = '?';
1280                 #endif
1281                         if (name) {
1282                                 WARNING("File, directory, or stream name \"%"WS"\"\n"
1283                                         "          contains forbidden characters; "
1284                                         "substituting replacement characters.",
1285                                         name);
1286                                 name = NULL;
1287                         }
1288                 }
1289         }
1290 }
1291
1292 /*
1293  * Reads the alternate data stream entries of a WIM dentry.
1294  *
1295  * @p:  Pointer to buffer that starts with the first alternate stream entry.
1296  *
1297  * @inode:      Inode to load the alternate data streams into.
1298  *                      @inode->i_num_ads must have been set to the number of
1299  *                      alternate data streams that are expected.
1300  *
1301  * @remaining_size:     Number of bytes of data remaining in the buffer pointed
1302  *                              to by @p.
1303  *
1304  * The format of the on-disk alternate stream entries is as follows:
1305  *
1306  * struct wim_ads_entry_on_disk {
1307  *      u64  length;          // Length of the entry, in bytes.  This includes
1308  *                                  all fields (including the stream name and
1309  *                                  null terminator if present, AND the padding!).
1310  *      u64  reserved;        // Seems to be unused
1311  *      u8   hash[20];        // SHA1 message digest of the uncompressed stream
1312  *      u16  stream_name_len; // Length of the stream name, in bytes
1313  *      char stream_name[];   // Stream name in UTF-16LE, @stream_name_len bytes long,
1314  *                                  not including null terminator
1315  *      u16  zero;            // UTF-16 null terminator for the stream name, NOT
1316  *                                  included in @stream_name_len.  Based on what
1317  *                                  I've observed from filenames in dentries,
1318  *                                  this field should not exist when
1319  *                                  (@stream_name_len == 0), but you can't
1320  *                                  actually tell because of the padding anyway
1321  *                                  (provided that the padding is zeroed, which
1322  *                                  it always seems to be).
1323  *      char padding[];       // Padding to make the size a multiple of 8 bytes.
1324  * };
1325  *
1326  * In addition, the entries are 8-byte aligned.
1327  *
1328  * Return 0 on success or nonzero on failure.  On success, inode->i_ads_entries
1329  * is set to an array of `struct wim_ads_entry's of length inode->i_num_ads.  On
1330  * failure, @inode is not modified.
1331  */
1332 static int
1333 read_ads_entries(const u8 *p, struct wim_inode *inode, u64 remaining_size)
1334 {
1335         u16 num_ads;
1336         struct wim_ads_entry *ads_entries;
1337         int ret;
1338
1339         num_ads = inode->i_num_ads;
1340         ads_entries = CALLOC(num_ads, sizeof(inode->i_ads_entries[0]));
1341         if (!ads_entries) {
1342                 ERROR("Could not allocate memory for %"PRIu16" "
1343                       "alternate data stream entries", num_ads);
1344                 return WIMLIB_ERR_NOMEM;
1345         }
1346
1347         for (u16 i = 0; i < num_ads; i++) {
1348                 struct wim_ads_entry *cur_entry;
1349                 u64 length;
1350                 u64 length_no_padding;
1351                 u64 total_length;
1352                 const u8 *p_save = p;
1353
1354                 cur_entry = &ads_entries[i];
1355
1356         #ifdef WITH_FUSE
1357                 ads_entries[i].stream_id = i + 1;
1358         #endif
1359
1360                 /* Read the base stream entry, excluding the stream name. */
1361                 if (remaining_size < WIM_ADS_ENTRY_DISK_SIZE) {
1362                         ERROR("Stream entries go past end of metadata resource");
1363                         ERROR("(remaining_size = %"PRIu64")", remaining_size);
1364                         ret = WIMLIB_ERR_INVALID_DENTRY;
1365                         goto out_free_ads_entries;
1366                 }
1367
1368                 p = get_u64(p, &length);
1369                 p = get_u64(p, &cur_entry->unused);
1370                 p = get_bytes(p, SHA1_HASH_SIZE, cur_entry->hash);
1371                 p = get_u16(p, &cur_entry->stream_name_nbytes);
1372
1373                 cur_entry->stream_name = NULL;
1374
1375                 /* Length including neither the null terminator nor the padding
1376                  * */
1377                 length_no_padding = WIM_ADS_ENTRY_DISK_SIZE +
1378                                     cur_entry->stream_name_nbytes;
1379
1380                 /* Length including the null terminator and the padding */
1381                 total_length = ((length_no_padding + 2) + 7) & ~7;
1382
1383                 wimlib_assert(total_length == ads_entry_total_length(cur_entry));
1384
1385                 if (remaining_size < length_no_padding) {
1386                         ERROR("Stream entries go past end of metadata resource");
1387                         ERROR("(remaining_size = %"PRIu64" bytes, "
1388                               "length_no_padding = %"PRIu64" bytes)",
1389                               remaining_size, length_no_padding);
1390                         ret = WIMLIB_ERR_INVALID_DENTRY;
1391                         goto out_free_ads_entries;
1392                 }
1393
1394                 /* The @length field in the on-disk ADS entry is expected to be
1395                  * equal to @total_length, which includes all of the entry and
1396                  * the padding that follows it to align the next ADS entry to an
1397                  * 8-byte boundary.  However, to be safe, we'll accept the
1398                  * length field as long as it's not less than the un-padded
1399                  * total length and not more than the padded total length. */
1400                 if (length < length_no_padding || length > total_length) {
1401                         ERROR("Stream entry has unexpected length "
1402                               "field (length field = %"PRIu64", "
1403                               "unpadded total length = %"PRIu64", "
1404                               "padded total length = %"PRIu64")",
1405                               length, length_no_padding, total_length);
1406                         ret = WIMLIB_ERR_INVALID_DENTRY;
1407                         goto out_free_ads_entries;
1408                 }
1409
1410                 if (cur_entry->stream_name_nbytes) {
1411                         cur_entry->stream_name = MALLOC(cur_entry->stream_name_nbytes + 2);
1412                         if (!cur_entry->stream_name) {
1413                                 ret = WIMLIB_ERR_NOMEM;
1414                                 goto out_free_ads_entries;
1415                         }
1416                         get_bytes(p, cur_entry->stream_name_nbytes,
1417                                   cur_entry->stream_name);
1418                         cur_entry->stream_name[cur_entry->stream_name_nbytes / 2] = 0;
1419                         replace_forbidden_characters(cur_entry->stream_name);
1420                 }
1421                 /* It's expected that the size of every ADS entry is a multiple
1422                  * of 8.  However, to be safe, I'm allowing the possibility of
1423                  * an ADS entry at the very end of the metadata resource ending
1424                  * un-aligned.  So although we still need to increment the input
1425                  * pointer by @total_length to reach the next ADS entry, it's
1426                  * possible that less than @total_length is actually remaining
1427                  * in the metadata resource. We should set the remaining size to
1428                  * 0 bytes if this happens. */
1429                 p = p_save + total_length;
1430                 if (remaining_size < total_length)
1431                         remaining_size = 0;
1432                 else
1433                         remaining_size -= total_length;
1434         }
1435         inode->i_ads_entries = ads_entries;
1436 #ifdef WITH_FUSE
1437         inode->i_next_stream_id = inode->i_num_ads + 1;
1438 #endif
1439         return 0;
1440 out_free_ads_entries:
1441         for (u16 i = 0; i < num_ads; i++)
1442                 destroy_ads_entry(&ads_entries[i]);
1443         FREE(ads_entries);
1444         return ret;
1445 }
1446
1447 /*
1448  * Reads a WIM directory entry, including all alternate data stream entries that
1449  * follow it, from the WIM image's metadata resource.
1450  *
1451  * @metadata_resource:  Buffer containing the uncompressed metadata resource.
1452  * @metadata_resource_len:   Length of the metadata resource.
1453  * @offset:     Offset of this directory entry in the metadata resource.
1454  * @dentry:     A `struct wim_dentry' that will be filled in by this function.
1455  *
1456  * Return 0 on success or nonzero on failure.  On failure, @dentry will have
1457  * been modified, but it will not be left with pointers to any allocated
1458  * buffers.  On success, the dentry->length field must be examined.  If zero,
1459  * this was a special "end of directory" dentry and not a real dentry.  If
1460  * nonzero, this was a real dentry.
1461  */
1462 int
1463 read_dentry(const u8 metadata_resource[], u64 metadata_resource_len,
1464             u64 offset, struct wim_dentry *dentry)
1465 {
1466         const u8 *p;
1467         u64 calculated_size;
1468         utf16lechar *file_name = NULL;
1469         utf16lechar *short_name = NULL;
1470         u16 short_name_nbytes;
1471         u16 file_name_nbytes;
1472         int ret;
1473         struct wim_inode *inode = NULL;
1474
1475         dentry_common_init(dentry);
1476
1477         /*Make sure the dentry really fits into the metadata resource.*/
1478         if (offset + 8 > metadata_resource_len || offset + 8 < offset) {
1479                 ERROR("Directory entry starting at %"PRIu64" ends past the "
1480                       "end of the metadata resource (size %"PRIu64")",
1481                       offset, metadata_resource_len);
1482                 return WIMLIB_ERR_INVALID_DENTRY;
1483         }
1484
1485         /* Before reading the whole dentry, we need to read just the length.
1486          * This is because a dentry of length 8 (that is, just the length field)
1487          * terminates the list of sibling directory entries. */
1488
1489         p = get_u64(&metadata_resource[offset], &dentry->length);
1490
1491         /* A zero length field (really a length of 8, since that's how big the
1492          * directory entry is...) indicates that this is the end of directory
1493          * dentry.  We do not read it into memory as an actual dentry, so just
1494          * return successfully in that case. */
1495         if (dentry->length == 0)
1496                 return 0;
1497
1498         /* If the dentry does not overflow the metadata resource buffer and is
1499          * not too short, read the rest of it (excluding the alternate data
1500          * streams, but including the file name and short name variable-length
1501          * fields) into memory. */
1502         if (offset + dentry->length >= metadata_resource_len
1503             || offset + dentry->length < offset)
1504         {
1505                 ERROR("Directory entry at offset %"PRIu64" and with size "
1506                       "%"PRIu64" ends past the end of the metadata resource "
1507                       "(size %"PRIu64")",
1508                       offset, dentry->length, metadata_resource_len);
1509                 return WIMLIB_ERR_INVALID_DENTRY;
1510         }
1511
1512         if (dentry->length < WIM_DENTRY_DISK_SIZE) {
1513                 ERROR("Directory entry has invalid length of %"PRIu64" bytes",
1514                       dentry->length);
1515                 return WIMLIB_ERR_INVALID_DENTRY;
1516         }
1517
1518         inode = new_timeless_inode();
1519         if (!inode)
1520                 return WIMLIB_ERR_NOMEM;
1521
1522         p = get_u32(p, &inode->i_attributes);
1523         p = get_u32(p, (u32*)&inode->i_security_id);
1524         p = get_u64(p, &dentry->subdir_offset);
1525
1526         p = get_u64(p, &inode->i_unused_1);
1527         p = get_u64(p, &inode->i_unused_2);
1528
1529         p = get_u64(p, &inode->i_creation_time);
1530         p = get_u64(p, &inode->i_last_access_time);
1531         p = get_u64(p, &inode->i_last_write_time);
1532
1533         p = get_bytes(p, SHA1_HASH_SIZE, inode->i_hash);
1534
1535         /* I don't know what's going on here.  It seems like M$ screwed up the
1536          * reparse points, then put the fields in the same place and didn't
1537          * document it.  */
1538         if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
1539                 p = get_u32(p, &inode->i_rp_unknown_1);
1540                 p = get_u32(p, &inode->i_reparse_tag);
1541                 p = get_u16(p, &inode->i_rp_unknown_2);
1542                 p = get_u16(p, &inode->i_not_rpfixed);
1543         } else {
1544                 p = get_u32(p, &inode->i_rp_unknown_1);
1545                 p = get_u64(p, &inode->i_ino);
1546         }
1547
1548         /* By the way, the reparse_reserved field does not actually exist (at
1549          * least when the file is not a reparse point) */
1550
1551         p = get_u16(p, &inode->i_num_ads);
1552
1553         p = get_u16(p, &short_name_nbytes);
1554         p = get_u16(p, &file_name_nbytes);
1555
1556         /* We now know the length of the file name and short name.  Make sure
1557          * the length of the dentry is large enough to actually hold them.
1558          *
1559          * The calculated length here is unaligned to allow for the possibility
1560          * that the dentry->length names an unaligned length, although this
1561          * would be unexpected. */
1562         calculated_size = __dentry_correct_length_unaligned(file_name_nbytes,
1563                                                             short_name_nbytes);
1564
1565         if (dentry->length < calculated_size) {
1566                 ERROR("Unexpected end of directory entry! (Expected "
1567                       "at least %"PRIu64" bytes, got %"PRIu64" bytes. "
1568                       "short_name_nbytes = %hu, file_name_nbytes = %hu)",
1569                       calculated_size, dentry->length,
1570                       short_name_nbytes, file_name_nbytes);
1571                 ret = WIMLIB_ERR_INVALID_DENTRY;
1572                 goto out_free_inode;
1573         }
1574
1575         /* Read the filename if present.  Note: if the filename is empty, there
1576          * is no null terminator following it. */
1577         if (file_name_nbytes) {
1578                 file_name = MALLOC(file_name_nbytes + 2);
1579                 if (!file_name) {
1580                         ERROR("Failed to allocate %d bytes for dentry file name",
1581                               file_name_nbytes + 2);
1582                         ret = WIMLIB_ERR_NOMEM;
1583                         goto out_free_inode;
1584                 }
1585                 p = get_bytes(p, file_name_nbytes + 2, file_name);
1586                 if (file_name[file_name_nbytes / 2] != 0) {
1587                         file_name[file_name_nbytes / 2] = 0;
1588                         WARNING("File name in WIM dentry \"%"WS"\" is not "
1589                                 "null-terminated!", file_name);
1590                 }
1591                 replace_forbidden_characters(file_name);
1592         }
1593
1594         /* Align the calculated size */
1595         calculated_size = (calculated_size + 7) & ~7;
1596
1597         if (dentry->length > calculated_size) {
1598                 /* Weird; the dentry says it's longer than it should be.  Note
1599                  * that the length field does NOT include the size of the
1600                  * alternate stream entries. */
1601
1602                 /* Strangely, some directory entries inexplicably have a little
1603                  * over 70 bytes of extra data.  The exact amount of data seems
1604                  * to be 72 bytes, but it is aligned on the next 8-byte
1605                  * boundary.  It does NOT seem to be alternate data stream
1606                  * entries.  Here's an example of the aligned data:
1607                  *
1608                  * 01000000 40000000 6c786bba c58ede11 b0bb0026 1870892a b6adb76f
1609                  * e63a3e46 8fca8653 0d2effa1 6c786bba c58ede11 b0bb0026 1870892a
1610                  * 00000000 00000000 00000000 00000000
1611                  *
1612                  * Here's one interpretation of how the data is laid out.
1613                  *
1614                  * struct unknown {
1615                  *      u32 field1; (always 0x00000001)
1616                  *      u32 field2; (always 0x40000000)
1617                  *      u8  data[48]; (???)
1618                  *      u64 reserved1; (always 0)
1619                  *      u64 reserved2; (always 0)
1620                  * };*/
1621                 /*DEBUG("Dentry for file or directory `%"WS"' has %"PRIu64" "*/
1622                       /*"extra bytes of data", file_name,*/
1623                       /*dentry->length - calculated_size);*/
1624         }
1625
1626         /* Read the short filename if present.  Note: if there is no short
1627          * filename, there is no null terminator following it. */
1628         if (short_name_nbytes) {
1629                 short_name = MALLOC(short_name_nbytes + 2);
1630                 if (!short_name) {
1631                         ERROR("Failed to allocate %d bytes for dentry short name",
1632                               short_name_nbytes + 2);
1633                         ret = WIMLIB_ERR_NOMEM;
1634                         goto out_free_file_name;
1635                 }
1636                 p = get_bytes(p, short_name_nbytes + 2, short_name);
1637                 if (short_name[short_name_nbytes / 2] != 0) {
1638                         short_name[short_name_nbytes / 2] = 0;
1639                         WARNING("Short name in WIM dentry \"%"WS"\" is not "
1640                                 "null-terminated!", file_name);
1641                 }
1642                 replace_forbidden_characters(short_name);
1643         }
1644
1645         /*
1646          * Read the alternate data streams, if present.  dentry->num_ads tells
1647          * us how many they are, and they will directly follow the dentry
1648          * on-disk.
1649          *
1650          * Note that each alternate data stream entry begins on an 8-byte
1651          * aligned boundary, and the alternate data stream entries are NOT
1652          * included in the dentry->length field for some reason.
1653          */
1654         if (inode->i_num_ads != 0) {
1655
1656                 /* Trying different lengths is just a hack to make sure we have
1657                  * a chance of reading the ADS entries correctly despite the
1658                  * poor documentation. */
1659
1660                 if (calculated_size != dentry->length) {
1661                         WARNING("Trying calculated dentry length (%"PRIu64") "
1662                                 "instead of dentry->length field (%"PRIu64") "
1663                                 "to read ADS entries",
1664                                 calculated_size, dentry->length);
1665                 }
1666                 u64 lengths_to_try[3] = {calculated_size,
1667                                          (dentry->length + 7) & ~7,
1668                                          dentry->length};
1669                 ret = WIMLIB_ERR_INVALID_DENTRY;
1670                 for (size_t i = 0; i < ARRAY_LEN(lengths_to_try); i++) {
1671                         if (lengths_to_try[i] > metadata_resource_len - offset)
1672                                 continue;
1673                         ret = read_ads_entries(&metadata_resource[offset + lengths_to_try[i]],
1674                                                inode,
1675                                                metadata_resource_len - offset - lengths_to_try[i]);
1676                         if (ret == 0)
1677                                 goto out;
1678                 }
1679                 ERROR("Failed to read alternate data stream "
1680                       "entries of WIM dentry \"%"WS"\"", file_name);
1681                 goto out_free_short_name;
1682         }
1683 out:
1684         /* We've read all the data for this dentry.  Set the names and their
1685          * lengths, and we've done. */
1686         dentry->d_inode           = inode;
1687         dentry->file_name         = file_name;
1688         dentry->short_name        = short_name;
1689         dentry->file_name_nbytes  = file_name_nbytes;
1690         dentry->short_name_nbytes = short_name_nbytes;
1691         return 0;
1692 out_free_short_name:
1693         FREE(short_name);
1694 out_free_file_name:
1695         FREE(file_name);
1696 out_free_inode:
1697         free_inode(inode);
1698         return ret;
1699 }
1700
1701 /* Reads the children of a dentry, and all their children, ..., etc. from the
1702  * metadata resource and into the dentry tree.
1703  *
1704  * @metadata_resource:  An array that contains the uncompressed metadata
1705  *                      resource for the WIM file.
1706  *
1707  * @metadata_resource_len:  The length of the uncompressed metadata resource, in
1708  *                          bytes.
1709  *
1710  * @dentry:     A pointer to a `struct wim_dentry' that is the root of the directory
1711  *              tree and has already been read from the metadata resource.  It
1712  *              does not need to be the real root because this procedure is
1713  *              called recursively.
1714  *
1715  * Returns zero on success; nonzero on failure.
1716  */
1717 int
1718 read_dentry_tree(const u8 metadata_resource[], u64 metadata_resource_len,
1719                  struct wim_dentry *dentry)
1720 {
1721         u64 cur_offset = dentry->subdir_offset;
1722         struct wim_dentry *child;
1723         struct wim_dentry cur_child;
1724         int ret;
1725
1726         /*
1727          * If @dentry has no child dentries, nothing more needs to be done for
1728          * this branch.  This is the case for regular files, symbolic links, and
1729          * *possibly* empty directories (although an empty directory may also
1730          * have one child dentry that is the special end-of-directory dentry)
1731          */
1732         if (cur_offset == 0)
1733                 return 0;
1734
1735         /* Find and read all the children of @dentry. */
1736         while (1) {
1737
1738                 /* Read next child of @dentry into @cur_child. */
1739                 ret = read_dentry(metadata_resource, metadata_resource_len,
1740                                   cur_offset, &cur_child);
1741                 if (ret != 0)
1742                         break;
1743
1744                 /* Check for end of directory. */
1745                 if (cur_child.length == 0)
1746                         break;
1747
1748                 /* Not end of directory.  Allocate this child permanently and
1749                  * link it to the parent and previous child. */
1750                 child = MALLOC(sizeof(struct wim_dentry));
1751                 if (!child) {
1752                         ERROR("Failed to allocate %zu bytes for new dentry",
1753                               sizeof(struct wim_dentry));
1754                         ret = WIMLIB_ERR_NOMEM;
1755                         break;
1756                 }
1757                 memcpy(child, &cur_child, sizeof(struct wim_dentry));
1758                 dentry_add_child(dentry, child);
1759                 inode_add_dentry(child, child->d_inode);
1760
1761                 /* If there are children of this child, call this procedure
1762                  * recursively. */
1763                 if (child->subdir_offset != 0) {
1764                         ret = read_dentry_tree(metadata_resource,
1765                                                metadata_resource_len, child);
1766                         if (ret != 0)
1767                                 break;
1768                 }
1769
1770                 /* Advance to the offset of the next child.  Note: We need to
1771                  * advance by the TOTAL length of the dentry, not by the length
1772                  * child->length, which although it does take into account the
1773                  * padding, it DOES NOT take into account alternate stream
1774                  * entries. */
1775                 cur_offset += dentry_total_length(child);
1776         }
1777         return ret;
1778 }
1779
1780 /*
1781  * Writes a WIM dentry to an output buffer.
1782  *
1783  * @dentry:  The dentry structure.
1784  * @p:       The memory location to write the data to.
1785  * @return:  Pointer to the byte after the last byte we wrote as part of the
1786  *              dentry.
1787  */
1788 static u8 *
1789 write_dentry(const struct wim_dentry *dentry, u8 *p)
1790 {
1791         u8 *orig_p = p;
1792         const u8 *hash;
1793         const struct wim_inode *inode = dentry->d_inode;
1794
1795         /* We calculate the correct length of the dentry ourselves because the
1796          * dentry->length field may been set to an unexpected value from when we
1797          * read the dentry in (for example, there may have been unknown data
1798          * appended to the end of the dentry...) */
1799         u64 length = dentry_correct_length(dentry);
1800
1801         p = put_u64(p, length);
1802         p = put_u32(p, inode->i_attributes);
1803         p = put_u32(p, inode->i_security_id);
1804         p = put_u64(p, dentry->subdir_offset);
1805         p = put_u64(p, inode->i_unused_1);
1806         p = put_u64(p, inode->i_unused_2);
1807         p = put_u64(p, inode->i_creation_time);
1808         p = put_u64(p, inode->i_last_access_time);
1809         p = put_u64(p, inode->i_last_write_time);
1810         hash = inode_stream_hash(inode, 0);
1811         p = put_bytes(p, SHA1_HASH_SIZE, hash);
1812         if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
1813                 p = put_u32(p, inode->i_rp_unknown_1);
1814                 p = put_u32(p, inode->i_reparse_tag);
1815                 p = put_u16(p, inode->i_rp_unknown_2);
1816                 p = put_u16(p, inode->i_not_rpfixed);
1817         } else {
1818                 u64 link_group_id;
1819                 p = put_u32(p, inode->i_rp_unknown_1);
1820                 if (inode->i_nlink == 1)
1821                         link_group_id = 0;
1822                 else
1823                         link_group_id = inode->i_ino;
1824                 p = put_u64(p, link_group_id);
1825         }
1826         p = put_u16(p, inode->i_num_ads);
1827         p = put_u16(p, dentry->short_name_nbytes);
1828         p = put_u16(p, dentry->file_name_nbytes);
1829         if (dentry_has_long_name(dentry)) {
1830                 p = put_bytes(p, dentry->file_name_nbytes + 2,
1831                               dentry->file_name);
1832         }
1833         if (dentry_has_short_name(dentry)) {
1834                 p = put_bytes(p, dentry->short_name_nbytes + 2,
1835                               dentry->short_name);
1836         }
1837
1838         /* Align to 8-byte boundary */
1839         wimlib_assert(length >= (p - orig_p) && length - (p - orig_p) <= 7);
1840         p = put_zeroes(p, length - (p - orig_p));
1841
1842         /* Write the alternate data streams, if there are any.  Please see
1843          * read_ads_entries() for comments about the format of the on-disk
1844          * alternate data stream entries. */
1845         for (u16 i = 0; i < inode->i_num_ads; i++) {
1846                 p = put_u64(p, ads_entry_total_length(&inode->i_ads_entries[i]));
1847                 p = put_u64(p, inode->i_ads_entries[i].unused);
1848                 hash = inode_stream_hash(inode, i + 1);
1849                 p = put_bytes(p, SHA1_HASH_SIZE, hash);
1850                 p = put_u16(p, inode->i_ads_entries[i].stream_name_nbytes);
1851                 if (inode->i_ads_entries[i].stream_name_nbytes) {
1852                         p = put_bytes(p,
1853                                       inode->i_ads_entries[i].stream_name_nbytes + 2,
1854                                       inode->i_ads_entries[i].stream_name);
1855                 }
1856                 p = put_zeroes(p, (8 - (p - orig_p) % 8) % 8);
1857         }
1858         wimlib_assert(p - orig_p == __dentry_total_length(dentry, length));
1859         return p;
1860 }
1861
1862 static int
1863 write_dentry_cb(struct wim_dentry *dentry, void *_p)
1864 {
1865         u8 **p = _p;
1866         *p = write_dentry(dentry, *p);
1867         return 0;
1868 }
1869
1870 static u8 *
1871 write_dentry_tree_recursive(const struct wim_dentry *parent, u8 *p);
1872
1873 static int
1874 write_dentry_tree_recursive_cb(struct wim_dentry *dentry, void *_p)
1875 {
1876         u8 **p = _p;
1877         *p = write_dentry_tree_recursive(dentry, *p);
1878         return 0;
1879 }
1880
1881 /* Recursive function that writes a dentry tree rooted at @parent, not including
1882  * @parent itself, which has already been written. */
1883 static u8 *
1884 write_dentry_tree_recursive(const struct wim_dentry *parent, u8 *p)
1885 {
1886         /* Nothing to do if this dentry has no children. */
1887         if (parent->subdir_offset == 0)
1888                 return p;
1889
1890         /* Write child dentries and end-of-directory entry.
1891          *
1892          * Note: we need to write all of this dentry's children before
1893          * recursively writing the directory trees rooted at each of the child
1894          * dentries, since the on-disk dentries for a dentry's children are
1895          * always located at consecutive positions in the metadata resource! */
1896         for_dentry_child(parent, write_dentry_cb, &p);
1897
1898         /* write end of directory entry */
1899         p = put_u64(p, 0);
1900
1901         /* Recurse on children. */
1902         for_dentry_child(parent, write_dentry_tree_recursive_cb, &p);
1903         return p;
1904 }
1905
1906 /* Writes a directory tree to the metadata resource.
1907  *
1908  * @root:       Root of the dentry tree.
1909  * @p:          Pointer to a buffer with enough space for the dentry tree.
1910  *
1911  * Returns pointer to the byte after the last byte we wrote.
1912  */
1913 u8 *
1914 write_dentry_tree(const struct wim_dentry *root, u8 *p)
1915 {
1916         DEBUG("Writing dentry tree.");
1917         wimlib_assert(dentry_is_root(root));
1918
1919         /* If we're the root dentry, we have no parent that already
1920          * wrote us, so we need to write ourselves. */
1921         p = write_dentry(root, p);
1922
1923         /* Write end of directory entry after the root dentry just to be safe;
1924          * however the root dentry obviously cannot have any siblings. */
1925         p = put_u64(p, 0);
1926
1927         /* Recursively write the rest of the dentry tree. */
1928         return write_dentry_tree_recursive(root, p);
1929 }