cmds-restore.c

   1 /*
   2  * Copyright (C) 2011 Red Hat.  All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public
   6  * License v2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public
  14  * License along with this program; if not, write to the
  15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16  * Boston, MA 021110-1307, USA.
  17  */
  18
  19
  20 #include "kerncompat.h"
  21
  22 #include <ctype.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <unistd.h>
  26 #include <fcntl.h>
  27 #include <sys/stat.h>
  28 #include <sys/types.h>
  29 #include <lzo/lzoconf.h>
  30 #include <lzo/lzo1x.h>
  31 #include <zlib.h>
  32 #include <regex.h>
  33 #include <getopt.h>
  34 #include <sys/types.h>
  35 #include <sys/xattr.h>
  36
  37 #include "ctree.h"
  38 #include "disk-io.h"
  39 #include "print-tree.h"
  40 #include "transaction.h"
  41 #include "list.h"
  42 #include "volumes.h"
  43 #include "utils.h"
  44 #include "commands.h"
  45
  46 static char fs_name[PATH_MAX];
  47 static char path_name[PATH_MAX];
  48 static int get_snaps = 0;
  49 static int verbose = 0;
  50 static int restore_metadata = 0;
  51 static int ignore_errors = 0;
  52 static int overwrite = 0;
  53 static int get_xattrs = 0;
  54 static int dry_run = 0;
  55
  56 #define LZO_LEN 4
  57 #define PAGE_CACHE_SIZE 4096
  58 #define lzo1x_worst_compress(x) ((x) + ((x) / 16) + 64 + 3)
  59
  60 static int decompress_zlib(char *inbuf, char *outbuf, u64 compress_len,
  61                            u64 decompress_len)
  62 {
  63         z_stream strm;
  64         int ret;
  65
  66         memset(&strm, 0, sizeof(strm));
  67         ret = inflateInit(&strm);
  68         if (ret != Z_OK) {
  69                 fprintf(stderr, "inflate init returnd %d\n", ret);
  70                 return -1;
  71         }
  72
  73         strm.avail_in = compress_len;
  74         strm.next_in = (unsigned char *)inbuf;
  75         strm.avail_out = decompress_len;
  76         strm.next_out = (unsigned char *)outbuf;
  77         ret = inflate(&strm, Z_NO_FLUSH);
  78         if (ret != Z_STREAM_END) {
  79                 (void)inflateEnd(&strm);
  80                 fprintf(stderr, "failed to inflate: %d\n", ret);
  81                 return -1;
  82         }
  83
  84         (void)inflateEnd(&strm);
  85         return 0;
  86 }
  87 static inline size_t read_compress_length(unsigned char *buf)
  88 {
  89         __le32 dlen;
  90         memcpy(&dlen, buf, LZO_LEN);
  91         return le32_to_cpu(dlen);
  92 }
  93
  94 static int decompress_lzo(unsigned char *inbuf, char *outbuf, u64 compress_len,
  95                           u64 *decompress_len)
  96 {
  97         size_t new_len;
  98         size_t in_len;
  99         size_t out_len = 0;
 100         size_t tot_len;
 101         size_t tot_in;
 102         int ret;
 103
 104         ret = lzo_init();
 105         if (ret != LZO_E_OK) {
 106                 fprintf(stderr, "lzo init returned %d\n", ret);
 107                 return -1;
 108         }
 109
 110         tot_len = read_compress_length(inbuf);
 111         inbuf += LZO_LEN;
 112         tot_in = LZO_LEN;
 113
 114         while (tot_in < tot_len) {
 115                 size_t mod_page;
 116                 size_t rem_page;
 117                 in_len = read_compress_length(inbuf);
 118
 119                 if ((tot_in + LZO_LEN + in_len) > tot_len) {
 120                         fprintf(stderr, "bad compress length %lu\n",
 121                                 (unsigned long)in_len);
 122                         return -1;
 123                 }
 124
 125                 inbuf += LZO_LEN;
 126                 tot_in += LZO_LEN;
 127
 128                 new_len = lzo1x_worst_compress(PAGE_CACHE_SIZE);
 129                 ret = lzo1x_decompress_safe((const unsigned char *)inbuf, in_len,
 130                                             (unsigned char *)outbuf,
 131                                             (void *)&new_len, NULL);
 132                 if (ret != LZO_E_OK) {
 133                         fprintf(stderr, "failed to inflate: %d\n", ret);
 134                         return -1;
 135                 }
 136                 out_len += new_len;
 137                 outbuf += new_len;
 138                 inbuf += in_len;
 139                 tot_in += in_len;
 140
 141                 /*
 142                  * If the 4 byte header does not fit to the rest of the page we
 143                  * have to move to the next one, unless we read some garbage
 144                  */
 145                 mod_page = tot_in % PAGE_CACHE_SIZE;
 146                 rem_page = PAGE_CACHE_SIZE - mod_page;
 147                 if (rem_page < LZO_LEN) {
 148                         inbuf += rem_page;
 149                         tot_in += rem_page;
 150                 }
 151         }
 152
 153         *decompress_len = out_len;
 154
 155         return 0;
 156 }
 157
 158 static int decompress(char *inbuf, char *outbuf, u64 compress_len,
 159                       u64 *decompress_len, int compress)
 160 {
 161         switch (compress) {
 162         case BTRFS_COMPRESS_ZLIB:
 163                 return decompress_zlib(inbuf, outbuf, compress_len,
 164                                        *decompress_len);
 165         case BTRFS_COMPRESS_LZO:
 166                 return decompress_lzo((unsigned char *)inbuf, outbuf, compress_len,
 167                                       decompress_len);
 168         default:
 169                 break;
 170         }
 171
 172         fprintf(stderr, "invalid compression type: %d\n", compress);
 173         return -1;
 174 }
 175
 176 static int next_leaf(struct btrfs_root *root, struct btrfs_path *path)
 177 {
 178         int slot;
 179         int level = 1;
 180         int offset = 1;
 181         struct extent_buffer *c;
 182         struct extent_buffer *next = NULL;
 183
 184 again:
 185         for (; level < BTRFS_MAX_LEVEL; level++) {
 186                 if (path->nodes[level])
 187                         break;
 188         }
 189
 190         if (level >= BTRFS_MAX_LEVEL)
 191                 return 1;
 192
 193         slot = path->slots[level] + 1;
 194
 195         while(level < BTRFS_MAX_LEVEL) {
 196                 if (!path->nodes[level])
 197                         return 1;
 198
 199                 slot = path->slots[level] + offset;
 200                 c = path->nodes[level];
 201                 if (slot >= btrfs_header_nritems(c)) {
 202                         level++;
 203                         if (level == BTRFS_MAX_LEVEL)
 204                                 return 1;
 205                         offset = 1;
 206                         continue;
 207                 }
 208
 209                 if (path->reada)
 210                         reada_for_search(root, path, level, slot, 0);
 211
 212                 next = read_node_slot(root, c, slot);
 213                 if (extent_buffer_uptodate(next))
 214                         break;
 215                 offset++;
 216         }
 217         path->slots[level] = slot;
 218         while(1) {
 219                 level--;
 220                 c = path->nodes[level];
 221                 free_extent_buffer(c);
 222                 path->nodes[level] = next;
 223                 path->slots[level] = 0;
 224                 if (!level)
 225                         break;
 226                 if (path->reada)
 227                         reada_for_search(root, path, level, 0, 0);
 228                 next = read_node_slot(root, next, 0);
 229                 if (!extent_buffer_uptodate(next))
 230                         goto again;
 231         }
 232         return 0;
 233 }
 234
 235 static int copy_one_inline(int fd, struct btrfs_path *path, u64 pos)
 236 {
 237         struct extent_buffer *leaf = path->nodes[0];
 238         struct btrfs_file_extent_item *fi;
 239         char buf[4096];
 240         char *outbuf;
 241         u64 ram_size;
 242         ssize_t done;
 243         unsigned long ptr;
 244         int ret;
 245         int len;
 246         int inline_item_len;
 247         int compress;
 248
 249         fi = btrfs_item_ptr(leaf, path->slots[0],
 250                             struct btrfs_file_extent_item);
 251         ptr = btrfs_file_extent_inline_start(fi);
 252         len = btrfs_file_extent_inline_len(leaf, path->slots[0], fi);
 253         inline_item_len = btrfs_file_extent_inline_item_len(leaf, btrfs_item_nr(path->slots[0]));
 254         read_extent_buffer(leaf, buf, ptr, inline_item_len);
 255
 256         compress = btrfs_file_extent_compression(leaf, fi);
 257         if (compress == BTRFS_COMPRESS_NONE) {
 258                 done = pwrite(fd, buf, len, pos);
 259                 if (done < len) {
 260                         fprintf(stderr, "Short inline write, wanted %d, did "
 261                                 "%zd: %d\n", len, done, errno);
 262                         return -1;
 263                 }
 264                 return 0;
 265         }
 266
 267         ram_size = btrfs_file_extent_ram_bytes(leaf, fi);
 268         outbuf = calloc(1, ram_size);
 269         if (!outbuf) {
 270                 fprintf(stderr, "No memory\n");
 271                 return -ENOMEM;
 272         }
 273
 274         ret = decompress(buf, outbuf, len, &ram_size, compress);
 275         if (ret) {
 276                 free(outbuf);
 277                 return ret;
 278         }
 279
 280         done = pwrite(fd, outbuf, ram_size, pos);
 281         free(outbuf);
 282         if (done < ram_size) {
 283                 fprintf(stderr, "Short compressed inline write, wanted %Lu, "
 284                         "did %zd: %d\n", ram_size, done, errno);
 285                 return -1;
 286         }
 287
 288         return 0;
 289 }
 290
 291 static int copy_one_extent(struct btrfs_root *root, int fd,
 292                            struct extent_buffer *leaf,
 293                            struct btrfs_file_extent_item *fi, u64 pos)
 294 {
 295         struct btrfs_multi_bio *multi = NULL;
 296         struct btrfs_device *device;
 297         char *inbuf, *outbuf = NULL;
 298         ssize_t done, total = 0;
 299         u64 bytenr;
 300         u64 ram_size;
 301         u64 disk_size;
 302         u64 num_bytes;
 303         u64 length;
 304         u64 size_left;
 305         u64 dev_bytenr;
 306         u64 offset;
 307         u64 count = 0;
 308         int compress;
 309         int ret;
 310         int dev_fd;
 311         int mirror_num = 1;
 312         int num_copies;
 313
 314         compress = btrfs_file_extent_compression(leaf, fi);
 315         bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
 316         disk_size = btrfs_file_extent_disk_num_bytes(leaf, fi);
 317         ram_size = btrfs_file_extent_ram_bytes(leaf, fi);
 318         offset = btrfs_file_extent_offset(leaf, fi);
 319         num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
 320         size_left = disk_size;
 321         if (compress == BTRFS_COMPRESS_NONE)
 322                 bytenr += offset;
 323
 324         if (verbose && offset)
 325                 printf("offset is %Lu\n", offset);
 326         /* we found a hole */
 327         if (disk_size == 0)
 328                 return 0;
 329
 330         inbuf = malloc(size_left);
 331         if (!inbuf) {
 332                 fprintf(stderr, "No memory\n");
 333                 return -ENOMEM;
 334         }
 335
 336         if (compress != BTRFS_COMPRESS_NONE) {
 337                 outbuf = calloc(1, ram_size);
 338                 if (!outbuf) {
 339                         fprintf(stderr, "No memory\n");
 340                         free(inbuf);
 341                         return -ENOMEM;
 342                 }
 343         }
 344 again:
 345         length = size_left;
 346         ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
 347                               bytenr, &length, &multi, mirror_num, NULL);
 348         if (ret) {
 349                 fprintf(stderr, "Error mapping block %d\n", ret);
 350                 goto out;
 351         }
 352         device = multi->stripes[0].dev;
 353         dev_fd = device->fd;
 354         device->total_ios++;
 355         dev_bytenr = multi->stripes[0].physical;
 356         kfree(multi);
 357
 358         if (size_left < length)
 359                 length = size_left;
 360
 361         done = pread(dev_fd, inbuf+count, length, dev_bytenr);
 362         /* Need both checks, or we miss negative values due to u64 conversion */
 363         if (done < 0 || done < length) {
 364                 num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
 365                                               bytenr, length);
 366                 mirror_num++;
 367                 /* mirror_num is 1-indexed, so num_copies is a valid mirror. */
 368                 if (mirror_num > num_copies) {
 369                         ret = -1;
 370                         fprintf(stderr, "Exhausted mirrors trying to read\n");
 371                         goto out;
 372                 }
 373                 fprintf(stderr, "Trying another mirror\n");
 374                 goto again;
 375         }
 376
 377         mirror_num = 1;
 378         size_left -= length;
 379         count += length;
 380         bytenr += length;
 381         if (size_left)
 382                 goto again;
 383
 384         if (compress == BTRFS_COMPRESS_NONE) {
 385                 while (total < num_bytes) {
 386                         done = pwrite(fd, inbuf+total, num_bytes-total,
 387                                       pos+total);
 388                         if (done < 0) {
 389                                 ret = -1;
 390                                 fprintf(stderr, "Error writing: %d %s\n", errno, strerror(errno));
 391                                 goto out;
 392                         }
 393                         total += done;
 394                 }
 395                 ret = 0;
 396                 goto out;
 397         }
 398
 399         ret = decompress(inbuf, outbuf, disk_size, &ram_size, compress);
 400         if (ret) {
 401                 num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
 402                                               bytenr, length);
 403                 mirror_num++;
 404                 if (mirror_num >= num_copies) {
 405                         ret = -1;
 406                         goto out;
 407                 }
 408                 fprintf(stderr, "Trying another mirror\n");
 409                 goto again;
 410         }
 411
 412         while (total < num_bytes) {
 413                 done = pwrite(fd, outbuf + offset + total,
 414                               num_bytes - total,
 415                               pos + total);
 416                 if (done < 0) {
 417                         ret = -1;
 418                         goto out;
 419                 }
 420                 total += done;
 421         }
 422 out:
 423         free(inbuf);
 424         free(outbuf);
 425         return ret;
 426 }
 427
 428 enum loop_response {
 429         LOOP_STOP,
 430         LOOP_CONTINUE,
 431         LOOP_DONTASK
 432 };
 433
 434 static enum loop_response ask_to_continue(const char *file)
 435 {
 436         char buf[2];
 437         char *ret;
 438
 439         printf("We seem to be looping a lot on %s, do you want to keep going "
 440                "on ? (y/N/a): ", file);
 441 again:
 442         ret = fgets(buf, 2, stdin);
 443         if (*ret == '\n' || tolower(*ret) == 'n')
 444                 return LOOP_STOP;
 445         if (tolower(*ret) == 'a')
 446                 return LOOP_DONTASK;
 447         if (tolower(*ret) != 'y') {
 448                 printf("Please enter one of 'y', 'n', or 'a': ");
 449                 goto again;
 450         }
 451
 452         return LOOP_CONTINUE;
 453 }
 454
 455
 456 static int set_file_xattrs(struct btrfs_root *root, u64 inode,
 457                            int fd, const char *file_name)
 458 {
 459         struct btrfs_key key;
 460         struct btrfs_path *path;
 461         struct extent_buffer *leaf;
 462         struct btrfs_dir_item *di;
 463         u32 name_len = 0;
 464         u32 data_len = 0;
 465         u32 len = 0;
 466         u32 cur, total_len;
 467         char *name = NULL;
 468         char *data = NULL;
 469         int ret = 0;
 470
 471         key.objectid = inode;
 472         key.type = BTRFS_XATTR_ITEM_KEY;
 473         key.offset = 0;
 474
 475         path = btrfs_alloc_path();
 476         if (!path)
 477                 return -ENOMEM;
 478
 479         ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
 480         if (ret < 0)
 481                 goto out;
 482
 483         leaf = path->nodes[0];
 484         while (1) {
 485                 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
 486                         do {
 487                                 ret = next_leaf(root, path);
 488                                 if (ret < 0) {
 489                                         fprintf(stderr,
 490                                                 "Error searching for extended attributes: %d\n",
 491                                                 ret);
 492                                         goto out;
 493                                 } else if (ret) {
 494                                         /* No more leaves to search */
 495                                         ret = 0;
 496                                         goto out;
 497                                 }
 498                                 leaf = path->nodes[0];
 499                         } while (!leaf);
 500                         continue;
 501                 }
 502
 503                 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
 504                 if (key.type != BTRFS_XATTR_ITEM_KEY || key.objectid != inode)
 505                         break;
 506                 cur = 0;
 507                 total_len = btrfs_item_size_nr(leaf, path->slots[0]);
 508                 di = btrfs_item_ptr(leaf, path->slots[0],
 509                                     struct btrfs_dir_item);
 510
 511                 while (cur < total_len) {
 512                         len = btrfs_dir_name_len(leaf, di);
 513                         if (len > name_len) {
 514                                 free(name);
 515                                 name = (char *) malloc(len + 1);
 516                                 if (!name) {
 517                                         ret = -ENOMEM;
 518                                         goto out;
 519                                 }
 520                         }
 521                         read_extent_buffer(leaf, name,
 522                                            (unsigned long)(di + 1), len);
 523                         name[len] = '\0';
 524                         name_len = len;
 525
 526                         len = btrfs_dir_data_len(leaf, di);
 527                         if (len > data_len) {
 528                                 free(data);
 529                                 data = (char *) malloc(len);
 530                                 if (!data) {
 531                                         ret = -ENOMEM;
 532                                         goto out;
 533                                 }
 534                         }
 535                         read_extent_buffer(leaf, data,
 536                                            (unsigned long)(di + 1) + name_len,
 537                                            len);
 538                         data_len = len;
 539
 540                         if (fsetxattr(fd, name, data, data_len, 0)) {
 541                                 int err = errno;
 542
 543                                 fprintf(stderr,
 544                                         "Error setting extended attribute %s on file %s: %s\n",
 545                                         name, file_name, strerror(err));
 546                         }
 547
 548                         len = sizeof(*di) + name_len + data_len;
 549                         cur += len;
 550                         di = (struct btrfs_dir_item *)((char *)di + len);
 551                 }
 552                 path->slots[0]++;
 553         }
 554         ret = 0;
 555 out:
 556         btrfs_free_path(path);
 557         free(name);
 558         free(data);
 559
 560         return ret;
 561 }
 562
 563 static int copy_metadata(struct btrfs_root *root, int fd,
 564                 struct btrfs_key *key)
 565 {
 566         struct btrfs_path *path;
 567         struct btrfs_inode_item *inode_item;
 568         int ret;
 569
 570         path = btrfs_alloc_path();
 571         if (!path) {
 572                 fprintf(stderr, "ERROR: Ran out of memory\n");
 573                 return -ENOMEM;
 574         }
 575
 576         ret = btrfs_lookup_inode(NULL, root, path, key, 0);
 577         if (ret == 0) {
 578                 struct btrfs_timespec *bts;
 579                 struct timespec times[2];
 580
 581                 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
 582                                 struct btrfs_inode_item);
 583
 584                 ret = fchown(fd, btrfs_inode_uid(path->nodes[0], inode_item),
 585                                 btrfs_inode_gid(path->nodes[0], inode_item));
 586                 if (ret) {
 587                         fprintf(stderr, "ERROR: Failed to change owner: %s\n",
 588                                         strerror(errno));
 589                         goto out;
 590                 }
 591
 592                 ret = fchmod(fd, btrfs_inode_mode(path->nodes[0], inode_item));
 593                 if (ret) {
 594                         fprintf(stderr, "ERROR: Failed to change mode: %s\n",
 595                                         strerror(errno));
 596                         goto out;
 597                 }
 598
 599                 bts = btrfs_inode_atime(inode_item);
 600                 times[0].tv_sec = btrfs_timespec_sec(path->nodes[0], bts);
 601                 times[0].tv_nsec = btrfs_timespec_nsec(path->nodes[0], bts);
 602
 603                 bts = btrfs_inode_mtime(inode_item);
 604                 times[1].tv_sec = btrfs_timespec_sec(path->nodes[0], bts);
 605                 times[1].tv_nsec = btrfs_timespec_nsec(path->nodes[0], bts);
 606
 607                 ret = futimens(fd, times);
 608                 if (ret) {
 609                         fprintf(stderr, "ERROR: Failed to set times: %s\n",
 610                                         strerror(errno));
 611                         goto out;
 612                 }
 613         }
 614 out:
 615         btrfs_free_path(path);
 616         return ret;
 617 }
 618
 619 static int copy_file(struct btrfs_root *root, int fd, struct btrfs_key *key,
 620                      const char *file)
 621 {
 622         struct extent_buffer *leaf;
 623         struct btrfs_path *path;
 624         struct btrfs_file_extent_item *fi;
 625         struct btrfs_inode_item *inode_item;
 626         struct btrfs_timespec *bts;
 627         struct btrfs_key found_key;
 628         int ret;
 629         int extent_type;
 630         int compression;
 631         int loops = 0;
 632         u64 found_size = 0;
 633         struct timespec times[2];
 634         int times_ok = 0;
 635
 636         path = btrfs_alloc_path();
 637         if (!path) {
 638                 fprintf(stderr, "Ran out of memory\n");
 639                 return -ENOMEM;
 640         }
 641
 642         ret = btrfs_lookup_inode(NULL, root, path, key, 0);
 643         if (ret == 0) {
 644                 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
 645                                     struct btrfs_inode_item);
 646                 found_size = btrfs_inode_size(path->nodes[0], inode_item);
 647
 648                 if (restore_metadata) {
 649                         /*
 650                          * Change the ownership and mode now, set times when
 651                          * copyout is finished.
 652                          */
 653
 654                         ret = fchown(fd, btrfs_inode_uid(path->nodes[0], inode_item),
 655                                         btrfs_inode_gid(path->nodes[0], inode_item));
 656                         if (ret && !ignore_errors)
 657                                 goto out;
 658
 659                         ret = fchmod(fd, btrfs_inode_mode(path->nodes[0], inode_item));
 660                         if (ret && !ignore_errors)
 661                                 goto out;
 662
 663                         bts = btrfs_inode_atime(inode_item);
 664                         times[0].tv_sec = btrfs_timespec_sec(path->nodes[0], bts);
 665                         times[0].tv_nsec = btrfs_timespec_nsec(path->nodes[0], bts);
 666
 667                         bts = btrfs_inode_mtime(inode_item);
 668                         times[1].tv_sec = btrfs_timespec_sec(path->nodes[0], bts);
 669                         times[1].tv_nsec = btrfs_timespec_nsec(path->nodes[0], bts);
 670                         times_ok = 1;
 671                 }
 672         }
 673         btrfs_release_path(path);
 674
 675         key->offset = 0;
 676         key->type = BTRFS_EXTENT_DATA_KEY;
 677
 678         ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
 679         if (ret < 0) {
 680                 fprintf(stderr, "Error searching %d\n", ret);
 681                 goto out;
 682         }
 683
 684         leaf = path->nodes[0];
 685         while (!leaf) {
 686                 ret = next_leaf(root, path);
 687                 if (ret < 0) {
 688                         fprintf(stderr, "Error getting next leaf %d\n",
 689                                 ret);
 690                         goto out;
 691                 } else if (ret > 0) {
 692                         /* No more leaves to search */
 693                         ret = 0;
 694                         goto out;
 695                 }
 696                 leaf = path->nodes[0];
 697         }
 698
 699         while (1) {
 700                 if (loops >= 0 && loops++ >= 1024) {
 701                         enum loop_response resp;
 702
 703                         resp = ask_to_continue(file);
 704                         if (resp == LOOP_STOP)
 705                                 break;
 706                         else if (resp == LOOP_CONTINUE)
 707                                 loops = 0;
 708                         else if (resp == LOOP_DONTASK)
 709                                 loops = -1;
 710                 }
 711                 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
 712                         do {
 713                                 ret = next_leaf(root, path);
 714                                 if (ret < 0) {
 715                                         fprintf(stderr, "Error searching %d\n", ret);
 716                                         goto out;
 717                                 } else if (ret) {
 718                                         /* No more leaves to search */
 719                                         btrfs_free_path(path);
 720                                         goto set_size;
 721                                 }
 722                                 leaf = path->nodes[0];
 723                         } while (!leaf);
 724                         continue;
 725                 }
 726                 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
 727                 if (found_key.objectid != key->objectid)
 728                         break;
 729                 if (found_key.type != key->type)
 730                         break;
 731                 fi = btrfs_item_ptr(leaf, path->slots[0],
 732                                     struct btrfs_file_extent_item);
 733                 extent_type = btrfs_file_extent_type(leaf, fi);
 734                 compression = btrfs_file_extent_compression(leaf, fi);
 735                 if (compression >= BTRFS_COMPRESS_LAST) {
 736                         fprintf(stderr, "Don't support compression yet %d\n",
 737                                 compression);
 738                         ret = -1;
 739                         goto out;
 740                 }
 741
 742                 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC)
 743                         goto next;
 744                 if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
 745                         ret = copy_one_inline(fd, path, found_key.offset);
 746                         if (ret)
 747                                 goto out;
 748                 } else if (extent_type == BTRFS_FILE_EXTENT_REG) {
 749                         ret = copy_one_extent(root, fd, leaf, fi,
 750                                               found_key.offset);
 751                         if (ret)
 752                                 goto out;
 753                 } else {
 754                         printf("Weird extent type %d\n", extent_type);
 755                 }
 756 next:
 757                 path->slots[0]++;
 758         }
 759
 760         btrfs_free_path(path);
 761 set_size:
 762         if (found_size) {
 763                 ret = ftruncate(fd, (loff_t)found_size);
 764                 if (ret)
 765                         return ret;
 766         }
 767         if (get_xattrs) {
 768                 ret = set_file_xattrs(root, key->objectid, fd, file);
 769                 if (ret)
 770                         return ret;
 771         }
 772         if (restore_metadata && times_ok) {
 773                 ret = futimens(fd, times);
 774                 if (ret)
 775                         return ret;
 776         }
 777         return 0;
 778
 779 out:
 780         btrfs_free_path(path);
 781         return ret;
 782 }
 783
 784 /*
 785  * returns:
 786  *  0 if the file exists and should be skipped.
 787  *  1 if the file does NOT exist
 788  *  2 if the file exists but is OK to overwrite
 789  */
 790 static int overwrite_ok(const char * path)
 791 {
 792         static int warn = 0;
 793         struct stat st;
 794         int ret;
 795
 796         /* don't be fooled by symlinks */
 797         ret = fstatat(-1, path_name, &st, AT_SYMLINK_NOFOLLOW);
 798
 799         if (!ret) {
 800                 if (overwrite)
 801                         return 2;
 802
 803                 if (verbose || !warn)
 804                         printf("Skipping existing file"
 805                                    " %s\n", path);
 806                 if (!warn)
 807                         printf("If you wish to overwrite use -o\n");
 808                 warn = 1;
 809                 return 0;
 810         }
 811         return 1;
 812 }
 813
 814 static int search_dir(struct btrfs_root *root, struct btrfs_key *key,
 815                       const char *output_rootdir, const char *in_dir,
 816                       const regex_t *mreg)
 817 {
 818         struct btrfs_path *path;
 819         struct extent_buffer *leaf;
 820         struct btrfs_dir_item *dir_item;
 821         struct btrfs_key found_key, location;
 822         char filename[BTRFS_NAME_LEN + 1];
 823         unsigned long name_ptr;
 824         int name_len;
 825         int ret = 0;
 826         int fd;
 827         int loops = 0;
 828         u8 type;
 829
 830         path = btrfs_alloc_path();
 831         if (!path) {
 832                 fprintf(stderr, "Ran out of memory\n");
 833                 return -ENOMEM;
 834         }
 835
 836         key->offset = 0;
 837         key->type = BTRFS_DIR_INDEX_KEY;
 838
 839         ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
 840         if (ret < 0) {
 841                 fprintf(stderr, "Error searching %d\n", ret);
 842                 goto out;
 843         }
 844
 845         ret = 0;
 846
 847         leaf = path->nodes[0];
 848         while (!leaf) {
 849                 if (verbose > 1)
 850                         printf("No leaf after search, looking for the next "
 851                                "leaf\n");
 852                 ret = next_leaf(root, path);
 853                 if (ret < 0) {
 854                         fprintf(stderr, "Error getting next leaf %d\n",
 855                                 ret);
 856                         goto out;
 857                 } else if (ret > 0) {
 858                         /* No more leaves to search */
 859                         if (verbose)
 860                                 printf("Reached the end of the tree looking "
 861                                        "for the directory\n");
 862                         ret = 0;
 863                         goto out;
 864                 }
 865                 leaf = path->nodes[0];
 866         }
 867
 868         while (leaf) {
 869                 if (loops++ >= 1024) {
 870                         printf("We have looped trying to restore files in %s "
 871                                "too many times to be making progress, "
 872                                "stopping\n", in_dir);
 873                         break;
 874                 }
 875
 876                 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
 877                         do {
 878                                 ret = next_leaf(root, path);
 879                                 if (ret < 0) {
 880                                         fprintf(stderr, "Error searching %d\n",
 881                                                 ret);
 882                                         goto out;
 883                                 } else if (ret > 0) {
 884                                         /* No more leaves to search */
 885                                         if (verbose)
 886                                                 printf("Reached the end of "
 887                                                        "the tree searching the"
 888                                                        " directory\n");
 889                                         ret = 0;
 890                                         goto out;
 891                                 }
 892                                 leaf = path->nodes[0];
 893                         } while (!leaf);
 894                         continue;
 895                 }
 896                 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
 897                 if (found_key.objectid != key->objectid) {
 898                         if (verbose > 1)
 899                                 printf("Found objectid=%Lu, key=%Lu\n",
 900                                        found_key.objectid, key->objectid);
 901                         break;
 902                 }
 903                 if (found_key.type != key->type) {
 904                         if (verbose > 1)
 905                                 printf("Found type=%u, want=%u\n",
 906                                        found_key.type, key->type);
 907                         break;
 908                 }
 909                 dir_item = btrfs_item_ptr(leaf, path->slots[0],
 910                                           struct btrfs_dir_item);
 911                 name_ptr = (unsigned long)(dir_item + 1);
 912                 name_len = btrfs_dir_name_len(leaf, dir_item);
 913                 read_extent_buffer(leaf, filename, name_ptr, name_len);
 914                 filename[name_len] = '\0';
 915                 type = btrfs_dir_type(leaf, dir_item);
 916                 btrfs_dir_item_key_to_cpu(leaf, dir_item, &location);
 917
 918                 /* full path from root of btrfs being restored */
 919                 snprintf(fs_name, PATH_MAX, "%s/%s", in_dir, filename);
 920
 921                 if (mreg && REG_NOMATCH == regexec(mreg, fs_name, 0, NULL, 0))
 922                         goto next;
 923
 924                 /* full path from system root */
 925                 snprintf(path_name, PATH_MAX, "%s%s", output_rootdir, fs_name);
 926
 927                 /*
 928                  * At this point we're only going to restore directories and
 929                  * files, no symlinks or anything else.
 930                  */
 931                 if (type == BTRFS_FT_REG_FILE) {
 932                         if (!overwrite_ok(path_name))
 933                                 goto next;
 934
 935                         if (verbose)
 936                                 printf("Restoring %s\n", path_name);
 937                         if (dry_run)
 938                                 goto next;
 939                         fd = open(path_name, O_CREAT|O_WRONLY, 0644);
 940                         if (fd < 0) {
 941                                 fprintf(stderr, "Error creating %s: %d\n",
 942                                         path_name, errno);
 943                                 if (ignore_errors)
 944                                         goto next;
 945                                 ret = -1;
 946                                 goto out;
 947                         }
 948                         loops = 0;
 949                         ret = copy_file(root, fd, &location, path_name);
 950                         close(fd);
 951                         if (ret) {
 952                                 fprintf(stderr, "Error copying data for %s\n",
 953                                         path_name);
 954                                 if (ignore_errors)
 955                                         goto next;
 956                                 goto out;
 957                         }
 958                 } else if (type == BTRFS_FT_DIR) {
 959                         struct btrfs_root *search_root = root;
 960                         char *dir = strdup(fs_name);
 961
 962                         if (!dir) {
 963                                 fprintf(stderr, "Ran out of memory\n");
 964                                 ret = -ENOMEM;
 965                                 goto out;
 966                         }
 967
 968                         if (location.type == BTRFS_ROOT_ITEM_KEY) {
 969                                 /*
 970                                  * If we are a snapshot and this is the index
 971                                  * object to ourselves just skip it.
 972                                  */
 973                                 if (location.objectid ==
 974                                     root->root_key.objectid) {
 975                                         free(dir);
 976                                         goto next;
 977                                 }
 978
 979                                 location.offset = (u64)-1;
 980                                 search_root = btrfs_read_fs_root(root->fs_info,
 981                                                                  &location);
 982                                 if (IS_ERR(search_root)) {
 983                                         free(dir);
 984                                         fprintf(stderr, "Error reading "
 985                                                 "subvolume %s: %lu\n",
 986                                                 path_name,
 987                                                 PTR_ERR(search_root));
 988                                         if (ignore_errors)
 989                                                 goto next;
 990                                         ret = PTR_ERR(search_root);
 991                                         goto out;
 992                                 }
 993
 994                                 /*
 995                                  * A subvolume will have a key.offset of 0, a
 996                                  * snapshot will have key.offset of a transid.
 997                                  */
 998                                 if (search_root->root_key.offset != 0 &&
 999                                     get_snaps == 0) {
1000                                         free(dir);
1001                                         printf("Skipping snapshot %s\n",
1002                                                filename);
1003                                         goto next;
1004                                 }
1005                                 location.objectid = BTRFS_FIRST_FREE_OBJECTID;
1006                         }
1007
1008                         if (verbose)
1009                                 printf("Restoring %s\n", path_name);
1010
1011                         errno = 0;
1012                         if (dry_run)
1013                                 ret = 0;
1014                         else
1015                                 ret = mkdir(path_name, 0755);
1016                         if (ret && errno != EEXIST) {
1017                                 free(dir);
1018                                 fprintf(stderr, "Error mkdiring %s: %d\n",
1019                                         path_name, errno);
1020                                 if (ignore_errors)
1021                                         goto next;
1022                                 ret = -1;
1023                                 goto out;
1024                         }
1025                         loops = 0;
1026                         ret = search_dir(search_root, &location,
1027                                          output_rootdir, dir, mreg);
1028                         free(dir);
1029                         if (ret) {
1030                                 fprintf(stderr, "Error searching %s\n",
1031                                         path_name);
1032                                 if (ignore_errors)
1033                                         goto next;
1034                                 goto out;
1035                         }
1036                 }
1037 next:
1038                 path->slots[0]++;
1039         }
1040
1041         if (restore_metadata) {
1042                 snprintf(path_name, PATH_MAX, "%s%s", output_rootdir, in_dir);
1043                 fd = open(path_name, O_RDONLY);
1044                 if (fd < 0) {
1045                         fprintf(stderr, "ERROR: Failed to access %s to restore metadata\n",
1046                                         path_name);
1047                         if (!ignore_errors) {
1048                                 ret = -1;
1049                                 goto out;
1050                         }
1051                 } else {
1052                         /*
1053                          * Set owner/mode/time on the directory as well
1054                          */
1055                         key->type = BTRFS_INODE_ITEM_KEY;
1056                         ret = copy_metadata(root, fd, key);
1057                         close(fd);
1058                         if (ret && !ignore_errors)
1059                                 goto out;
1060                 }
1061         }
1062
1063         if (verbose)
1064                 printf("Done searching %s\n", in_dir);
1065 out:
1066         btrfs_free_path(path);
1067         return ret;
1068 }
1069
1070 static int do_list_roots(struct btrfs_root *root)
1071 {
1072         struct btrfs_key key;
1073         struct btrfs_key found_key;
1074         struct btrfs_disk_key disk_key;
1075         struct btrfs_path *path;
1076         struct extent_buffer *leaf;
1077         struct btrfs_root_item ri;
1078         unsigned long offset;
1079         int slot;
1080         int ret;
1081
1082         root = root->fs_info->tree_root;
1083         path = btrfs_alloc_path();
1084         if (!path) {
1085                 fprintf(stderr, "Failed to alloc path\n");
1086                 return -ENOMEM;
1087         }
1088
1089         key.offset = 0;
1090         key.objectid = 0;
1091         key.type = BTRFS_ROOT_ITEM_KEY;
1092
1093         ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1094         if (ret < 0) {
1095                 fprintf(stderr, "Failed to do search %d\n", ret);
1096                 btrfs_free_path(path);
1097                 return -1;
1098         }
1099
1100         leaf = path->nodes[0];
1101
1102         while (1) {
1103                 slot = path->slots[0];
1104                 if (slot >= btrfs_header_nritems(leaf)) {
1105                         ret = btrfs_next_leaf(root, path);
1106                         if (ret)
1107                                 break;
1108                         leaf = path->nodes[0];
1109                         slot = path->slots[0];
1110                 }
1111                 btrfs_item_key(leaf, &disk_key, slot);
1112                 btrfs_disk_key_to_cpu(&found_key, &disk_key);
1113                 if (btrfs_key_type(&found_key) != BTRFS_ROOT_ITEM_KEY) {
1114                         path->slots[0]++;
1115                         continue;
1116                 }
1117
1118                 offset = btrfs_item_ptr_offset(leaf, slot);
1119                 read_extent_buffer(leaf, &ri, offset, sizeof(ri));
1120                 printf(" tree ");
1121                 btrfs_print_key(&disk_key);
1122                 printf(" %Lu level %d\n", btrfs_root_bytenr(&ri),
1123                        btrfs_root_level(&ri));
1124                 path->slots[0]++;
1125         }
1126         btrfs_free_path(path);
1127
1128         return 0;
1129 }
1130
1131 static struct btrfs_root *open_fs(const char *dev, u64 root_location,
1132                                   int super_mirror, int list_roots)
1133 {
1134         struct btrfs_fs_info *fs_info = NULL;
1135         struct btrfs_root *root = NULL;
1136         u64 bytenr;
1137         int i;
1138
1139         for (i = super_mirror; i < BTRFS_SUPER_MIRROR_MAX; i++) {
1140                 bytenr = btrfs_sb_offset(i);
1141                 fs_info = open_ctree_fs_info(dev, bytenr, root_location,
1142                                              OPEN_CTREE_PARTIAL);
1143                 if (fs_info)
1144                         break;
1145                 fprintf(stderr, "Could not open root, trying backup super\n");
1146         }
1147
1148         if (!fs_info)
1149                 return NULL;
1150
1151         /*
1152          * All we really need to succeed is reading the chunk tree, everything
1153          * else we can do by hand, since we only need to read the tree root and
1154          * the fs_root.
1155          */
1156         if (!extent_buffer_uptodate(fs_info->tree_root->node)) {
1157                 u64 generation;
1158
1159                 root = fs_info->tree_root;
1160                 if (!root_location)
1161                         root_location = btrfs_super_root(fs_info->super_copy);
1162                 generation = btrfs_super_generation(fs_info->super_copy);
1163                 root->node = read_tree_block(root, root_location,
1164                                              root->leafsize, generation);
1165                 if (!extent_buffer_uptodate(root->node)) {
1166                         fprintf(stderr, "Error opening tree root\n");
1167                         close_ctree(root);
1168                         return NULL;
1169                 }
1170         }
1171
1172         if (!list_roots && !fs_info->fs_root) {
1173                 struct btrfs_key key;
1174
1175                 key.objectid = BTRFS_FS_TREE_OBJECTID;
1176                 key.type = BTRFS_ROOT_ITEM_KEY;
1177                 key.offset = (u64)-1;
1178                 fs_info->fs_root = btrfs_read_fs_root_no_cache(fs_info, &key);
1179                 if (IS_ERR(fs_info->fs_root)) {
1180                         fprintf(stderr, "Couldn't read fs root: %ld\n",
1181                                 PTR_ERR(fs_info->fs_root));
1182                         close_ctree(fs_info->tree_root);
1183                         return NULL;
1184                 }
1185         }
1186
1187         if (list_roots && do_list_roots(fs_info->tree_root)) {
1188                 close_ctree(fs_info->tree_root);
1189                 return NULL;
1190         }
1191
1192         return fs_info->fs_root;
1193 }
1194
1195 static int find_first_dir(struct btrfs_root *root, u64 *objectid)
1196 {
1197         struct btrfs_path *path;
1198         struct btrfs_key found_key;
1199         struct btrfs_key key;
1200         int ret = -1;
1201         int i;
1202
1203         key.objectid = 0;
1204         key.type = BTRFS_DIR_INDEX_KEY;
1205         key.offset = 0;
1206
1207         path = btrfs_alloc_path();
1208         if (!path) {
1209                 fprintf(stderr, "Ran out of memory\n");
1210                 return ret;
1211         }
1212
1213         ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1214         if (ret < 0) {
1215                 fprintf(stderr, "Error searching %d\n", ret);
1216                 goto out;
1217         }
1218
1219         if (!path->nodes[0]) {
1220                 fprintf(stderr, "No leaf!\n");
1221                 goto out;
1222         }
1223 again:
1224         for (i = path->slots[0];
1225              i < btrfs_header_nritems(path->nodes[0]); i++) {
1226                 btrfs_item_key_to_cpu(path->nodes[0], &found_key, i);
1227                 if (found_key.type != key.type)
1228                         continue;
1229
1230                 printf("Using objectid %Lu for first dir\n",
1231                        found_key.objectid);
1232                 *objectid = found_key.objectid;
1233                 ret = 0;
1234                 goto out;
1235         }
1236         do {
1237                 ret = next_leaf(root, path);
1238                 if (ret < 0) {
1239                         fprintf(stderr, "Error getting next leaf %d\n",
1240                                 ret);
1241                         goto out;
1242                 } else if (ret > 0) {
1243                         fprintf(stderr, "No more leaves\n");
1244                         goto out;
1245                 }
1246         } while (!path->nodes[0]);
1247         if (path->nodes[0])
1248                 goto again;
1249         printf("Couldn't find a dir index item\n");
1250 out:
1251         btrfs_free_path(path);
1252         return ret;
1253 }
1254
1255 const char * const cmd_restore_usage[] = {
1256         "btrfs restore [options] <device> <path> | -l <device>",
1257         "Try to restore files from a damaged filesystem (unmounted)",
1258         "",
1259         "-s              get snapshots",
1260         "-x              get extended attributes",
1261         "-m|--metadata   restore owner, mode and times",
1262         "-v              verbose",
1263         "-i              ignore errors",
1264         "-o              overwrite",
1265         "-t <bytenr>     tree location",
1266         "-f <bytenr>     filesystem location",
1267         "-u <mirror>     super mirror",
1268         "-r <rootid>     root objectid",
1269         "-d              find dir",
1270         "-l              list tree roots",
1271         "-D|--dry-run    dry run (only list files that would be recovered)",
1272         "--path-regex <regex>",
1273         "                restore only filenames matching regex,",
1274         "                you have to use following syntax (possibly quoted):",
1275         "                ^/(|home(|/username(|/Desktop(|/.*))))$",
1276         "-c              ignore case (--path-regex only)",
1277         NULL
1278 };
1279
1280 int cmd_restore(int argc, char **argv)
1281 {
1282         struct btrfs_root *root;
1283         struct btrfs_key key;
1284         char dir_name[128];
1285         u64 tree_location = 0;
1286         u64 fs_location = 0;
1287         u64 root_objectid = 0;
1288         int len;
1289         int ret;
1290         int super_mirror = 0;
1291         int find_dir = 0;
1292         int list_roots = 0;
1293         const char *match_regstr = NULL;
1294         int match_cflags = REG_EXTENDED | REG_NOSUB | REG_NEWLINE;
1295         regex_t match_reg, *mreg = NULL;
1296         char reg_err[256];
1297
1298         while (1) {
1299                 int opt;
1300                 static const struct option long_options[] = {
1301                         { "path-regex", required_argument, NULL, 256},
1302                         { "dry-run", no_argument, NULL, 'D'},
1303                         { "metadata", no_argument, NULL, 'm'},
1304                         { NULL, 0, NULL, 0}
1305                 };
1306
1307                 opt = getopt_long(argc, argv, "sxviot:u:dmf:r:lDc", long_options,
1308                                         NULL);
1309                 if (opt < 0)
1310                         break;
1311
1312                 switch (opt) {
1313                         case 's':
1314                                 get_snaps = 1;
1315                                 break;
1316                         case 'v':
1317                                 verbose++;
1318                                 break;
1319                         case 'i':
1320                                 ignore_errors = 1;
1321                                 break;
1322                         case 'o':
1323                                 overwrite = 1;
1324                                 break;
1325                         case 't':
1326                                 tree_location = arg_strtou64(optarg);
1327                                 break;
1328                         case 'f':
1329                                 fs_location = arg_strtou64(optarg);
1330                                 break;
1331                         case 'u':
1332                                 super_mirror = arg_strtou64(optarg);
1333                                 if (super_mirror >= BTRFS_SUPER_MIRROR_MAX) {
1334                                         fprintf(stderr, "Super mirror not "
1335                                                 "valid\n");
1336                                         exit(1);
1337                                 }
1338                                 break;
1339                         case 'd':
1340                                 find_dir = 1;
1341                                 break;
1342                         case 'r':
1343                                 root_objectid = arg_strtou64(optarg);
1344                                 if (!is_fstree(root_objectid)) {
1345                                         fprintf(stderr, "objectid %llu is not a valid fs/file tree\n",
1346                                                         root_objectid);
1347                                         exit(1);
1348                                 }
1349                                 break;
1350                         case 'l':
1351                                 list_roots = 1;
1352                                 break;
1353                         case 'm':
1354                                 restore_metadata = 1;
1355                                 break;
1356                         case 'D':
1357                                 dry_run = 1;
1358                                 break;
1359                         case 'c':
1360                                 match_cflags |= REG_ICASE;
1361                                 break;
1362                         /* long option without single letter alternative */
1363                         case 256:
1364                                 match_regstr = optarg;
1365                                 break;
1366                         case 'x':
1367                                 get_xattrs = 1;
1368                                 break;
1369                         default:
1370                                 usage(cmd_restore_usage);
1371                 }
1372         }
1373
1374         if (!list_roots && check_argc_min(argc - optind, 2))
1375                 usage(cmd_restore_usage);
1376         else if (list_roots && check_argc_min(argc - optind, 1))
1377                 usage(cmd_restore_usage);
1378
1379         if (fs_location && root_objectid) {
1380                 fprintf(stderr, "don't use -f and -r at the same time.\n");
1381                 return 1;
1382         }
1383
1384         if ((ret = check_mounted(argv[optind])) < 0) {
1385                 fprintf(stderr, "Could not check mount status: %s\n",
1386                         strerror(-ret));
1387                 return 1;
1388         } else if (ret) {
1389                 fprintf(stderr, "%s is currently mounted.  Aborting.\n", argv[optind]);
1390                 return 1;
1391         }
1392
1393         root = open_fs(argv[optind], tree_location, super_mirror, list_roots);
1394         if (root == NULL)
1395                 return 1;
1396
1397         if (list_roots)
1398                 goto out;
1399
1400         if (fs_location != 0) {
1401                 free_extent_buffer(root->node);
1402                 root->node = read_tree_block(root, fs_location, root->leafsize, 0);
1403                 if (!extent_buffer_uptodate(root->node)) {
1404                         fprintf(stderr, "Failed to read fs location\n");
1405                         ret = 1;
1406                         goto out;
1407                 }
1408         }
1409
1410         memset(path_name, 0, PATH_MAX);
1411
1412         strncpy(dir_name, argv[optind + 1], sizeof dir_name);
1413         dir_name[sizeof dir_name - 1] = 0;
1414
1415         /* Strip the trailing / on the dir name */
1416         len = strlen(dir_name);
1417         while (len && dir_name[--len] == '/') {
1418                 dir_name[len] = '\0';
1419         }
1420
1421         if (root_objectid != 0) {
1422                 struct btrfs_root *orig_root = root;
1423
1424                 key.objectid = root_objectid;
1425                 key.type = BTRFS_ROOT_ITEM_KEY;
1426                 key.offset = (u64)-1;
1427                 root = btrfs_read_fs_root(orig_root->fs_info, &key);
1428                 if (IS_ERR(root)) {
1429                         fprintf(stderr, "fail to read root %llu: %s\n",
1430                                         root_objectid, strerror(-PTR_ERR(root)));
1431                         root = orig_root;
1432                         ret = 1;
1433                         goto out;
1434                 }
1435                 key.type = 0;
1436                 key.offset = 0;
1437         }
1438
1439         if (find_dir) {
1440                 ret = find_first_dir(root, &key.objectid);
1441                 if (ret)
1442                         goto out;
1443         } else {
1444                 key.objectid = BTRFS_FIRST_FREE_OBJECTID;
1445         }
1446
1447         if (match_regstr) {
1448                 ret = regcomp(&match_reg, match_regstr, match_cflags);
1449                 if (ret) {
1450                         regerror(ret, &match_reg, reg_err, sizeof(reg_err));
1451                         fprintf(stderr, "Regex compile failed: %s\n", reg_err);
1452                         goto out;
1453                 }
1454                 mreg = &match_reg;
1455         }
1456
1457         if (dry_run)
1458                 printf("This is a dry-run, no files are going to be restored\n");
1459
1460         ret = search_dir(root, &key, dir_name, "", mreg);
1461
1462 out:
1463         if (mreg)
1464                 regfree(mreg);
1465         close_ctree(root);
1466         return !!ret;
1467 }