cmds-receive.c

   1 /*
   2  * Copyright (C) 2012 Alexander Block.  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 #define _GNU_SOURCE
  20 #define _POSIX_C_SOURCE 200809
  21 #define _XOPEN_SOURCE 700
  22 #define _BSD_SOURCE
  23
  24 #include "kerncompat.h"
  25
  26 #include <unistd.h>
  27 #include <stdint.h>
  28 #include <dirent.h>
  29 #include <fcntl.h>
  30 #include <pthread.h>
  31 #include <math.h>
  32 #include <ftw.h>
  33 #include <wait.h>
  34 #include <assert.h>
  35
  36 #include <sys/stat.h>
  37 #include <sys/types.h>
  38 #include <sys/ioctl.h>
  39 #include <sys/time.h>
  40 #include <sys/types.h>
  41 #include <sys/xattr.h>
  42 #include <uuid/uuid.h>
  43
  44 #include "ctree.h"
  45 #include "ioctl.h"
  46 #include "commands.h"
  47 #include "utils.h"
  48 #include "list.h"
  49 #include "btrfs-list.h"
  50
  51 #include "send.h"
  52 #include "send-stream.h"
  53 #include "send-utils.h"
  54
  55 static int g_verbose = 0;
  56
  57 struct btrfs_receive
  58 {
  59         int mnt_fd;
  60         int dest_dir_fd;
  61
  62         int write_fd;
  63         char *write_path;
  64
  65         char *root_path;
  66         char *dest_dir_path; /* relative to root_path */
  67         char *full_subvol_path;
  68
  69         struct subvol_info *cur_subvol;
  70
  71         struct subvol_uuid_search sus;
  72
  73         int honor_end_cmd;
  74 };
  75
  76 static int finish_subvol(struct btrfs_receive *r)
  77 {
  78         int ret;
  79         int subvol_fd = -1;
  80         struct btrfs_ioctl_received_subvol_args rs_args;
  81         char uuid_str[128];
  82         u64 flags;
  83
  84         if (r->cur_subvol == NULL)
  85                 return 0;
  86
  87         subvol_fd = openat(r->mnt_fd, r->cur_subvol->path,
  88                         O_RDONLY | O_NOATIME);
  89         if (subvol_fd < 0) {
  90                 ret = -errno;
  91                 fprintf(stderr, "ERROR: open %s failed. %s\n",
  92                                 r->cur_subvol->path, strerror(-ret));
  93                 goto out;
  94         }
  95
  96         memset(&rs_args, 0, sizeof(rs_args));
  97         memcpy(rs_args.uuid, r->cur_subvol->received_uuid, BTRFS_UUID_SIZE);
  98         rs_args.stransid = r->cur_subvol->stransid;
  99
 100         if (g_verbose >= 1) {
 101                 uuid_unparse((u8*)rs_args.uuid, uuid_str);
 102                 fprintf(stderr, "BTRFS_IOC_SET_RECEIVED_SUBVOL uuid=%s, "
 103                                 "stransid=%llu\n", uuid_str, rs_args.stransid);
 104         }
 105
 106         ret = ioctl(subvol_fd, BTRFS_IOC_SET_RECEIVED_SUBVOL, &rs_args);
 107         if (ret < 0) {
 108                 ret = -errno;
 109                 fprintf(stderr, "ERROR: BTRFS_IOC_SET_RECEIVED_SUBVOL failed. %s\n",
 110                                 strerror(-ret));
 111                 goto out;
 112         }
 113         r->cur_subvol->rtransid = rs_args.rtransid;
 114
 115         ret = ioctl(subvol_fd, BTRFS_IOC_SUBVOL_GETFLAGS, &flags);
 116         if (ret < 0) {
 117                 ret = -errno;
 118                 fprintf(stderr, "ERROR: BTRFS_IOC_SUBVOL_GETFLAGS failed. %s\n",
 119                                 strerror(-ret));
 120                 goto out;
 121         }
 122
 123         flags |= BTRFS_SUBVOL_RDONLY;
 124
 125         ret = ioctl(subvol_fd, BTRFS_IOC_SUBVOL_SETFLAGS, &flags);
 126         if (ret < 0) {
 127                 ret = -errno;
 128                 fprintf(stderr, "ERROR: failed to make subvolume read only. "
 129                                 "%s\n", strerror(-ret));
 130                 goto out;
 131         }
 132
 133         ret = 0;
 134
 135 out:
 136         if (r->cur_subvol) {
 137                 free(r->cur_subvol->path);
 138                 free(r->cur_subvol);
 139                 r->cur_subvol = NULL;
 140         }
 141         if (subvol_fd != -1)
 142                 close(subvol_fd);
 143         return ret;
 144 }
 145
 146 static int process_subvol(const char *path, const u8 *uuid, u64 ctransid,
 147                           void *user)
 148 {
 149         int ret;
 150         struct btrfs_receive *r = user;
 151         struct btrfs_ioctl_vol_args args_v1;
 152         char uuid_str[128];
 153
 154         ret = finish_subvol(r);
 155         if (ret < 0)
 156                 goto out;
 157
 158         r->cur_subvol = calloc(1, sizeof(*r->cur_subvol));
 159
 160         if (strlen(r->dest_dir_path) == 0)
 161                 r->cur_subvol->path = strdup(path);
 162         else
 163                 r->cur_subvol->path = path_cat(r->dest_dir_path, path);
 164         free(r->full_subvol_path);
 165         r->full_subvol_path = path_cat3(r->root_path, r->dest_dir_path, path);
 166
 167         fprintf(stderr, "At subvol %s\n", path);
 168
 169         memcpy(r->cur_subvol->received_uuid, uuid, BTRFS_UUID_SIZE);
 170         r->cur_subvol->stransid = ctransid;
 171
 172         if (g_verbose) {
 173                 uuid_unparse((u8*)r->cur_subvol->received_uuid, uuid_str);
 174                 fprintf(stderr, "receiving subvol %s uuid=%s, stransid=%llu\n",
 175                                 path, uuid_str,
 176                                 r->cur_subvol->stransid);
 177         }
 178
 179         memset(&args_v1, 0, sizeof(args_v1));
 180         strncpy_null(args_v1.name, path);
 181         ret = ioctl(r->dest_dir_fd, BTRFS_IOC_SUBVOL_CREATE, &args_v1);
 182         if (ret < 0) {
 183                 ret = -errno;
 184                 fprintf(stderr, "ERROR: creating subvolume %s failed. "
 185                                 "%s\n", path, strerror(-ret));
 186                 goto out;
 187         }
 188
 189 out:
 190         return ret;
 191 }
 192
 193 static int process_snapshot(const char *path, const u8 *uuid, u64 ctransid,
 194                             const u8 *parent_uuid, u64 parent_ctransid,
 195                             void *user)
 196 {
 197         int ret;
 198         struct btrfs_receive *r = user;
 199         char uuid_str[128];
 200         struct btrfs_ioctl_vol_args_v2 args_v2;
 201         struct subvol_info *parent_subvol = NULL;
 202
 203         ret = finish_subvol(r);
 204         if (ret < 0)
 205                 goto out;
 206
 207         r->cur_subvol = calloc(1, sizeof(*r->cur_subvol));
 208
 209         if (strlen(r->dest_dir_path) == 0)
 210                 r->cur_subvol->path = strdup(path);
 211         else
 212                 r->cur_subvol->path = path_cat(r->dest_dir_path, path);
 213         free(r->full_subvol_path);
 214         r->full_subvol_path = path_cat3(r->root_path, r->dest_dir_path, path);
 215
 216         fprintf(stderr, "At snapshot %s\n", path);
 217
 218         memcpy(r->cur_subvol->received_uuid, uuid, BTRFS_UUID_SIZE);
 219         r->cur_subvol->stransid = ctransid;
 220
 221         if (g_verbose) {
 222                 uuid_unparse((u8*)r->cur_subvol->received_uuid, uuid_str);
 223                 fprintf(stderr, "receiving snapshot %s uuid=%s, "
 224                                 "ctransid=%llu ", path, uuid_str,
 225                                 r->cur_subvol->stransid);
 226                 uuid_unparse(parent_uuid, uuid_str);
 227                 fprintf(stderr, "parent_uuid=%s, parent_ctransid=%llu\n",
 228                                 uuid_str, parent_ctransid);
 229         }
 230
 231         memset(&args_v2, 0, sizeof(args_v2));
 232         strncpy_null(args_v2.name, path);
 233
 234         parent_subvol = subvol_uuid_search(&r->sus, 0, parent_uuid,
 235                         parent_ctransid, NULL, subvol_search_by_received_uuid);
 236         if (!parent_subvol) {
 237                 ret = -ENOENT;
 238                 fprintf(stderr, "ERROR: could not find parent subvolume\n");
 239                 goto out;
 240         }
 241
 242         /*if (rs_args.ctransid > rs_args.rtransid) {
 243                 if (!r->force) {
 244                         ret = -EINVAL;
 245                         fprintf(stderr, "ERROR: subvolume %s was modified after it was received.\n", r->subvol_parent_name);
 246                         goto out;
 247                 } else {
 248                         fprintf(stderr, "WARNING: subvolume %s was modified after it was received.\n", r->subvol_parent_name);
 249                 }
 250         }*/
 251
 252         args_v2.fd = openat(r->mnt_fd, parent_subvol->path,
 253                         O_RDONLY | O_NOATIME);
 254         if (args_v2.fd < 0) {
 255                 ret = -errno;
 256                 fprintf(stderr, "ERROR: open %s failed. %s\n",
 257                                 parent_subvol->path, strerror(-ret));
 258                 goto out;
 259         }
 260
 261         ret = ioctl(r->dest_dir_fd, BTRFS_IOC_SNAP_CREATE_V2, &args_v2);
 262         close(args_v2.fd);
 263         if (ret < 0) {
 264                 ret = -errno;
 265                 fprintf(stderr, "ERROR: creating snapshot %s -> %s "
 266                                 "failed. %s\n", parent_subvol->path,
 267                                 path, strerror(-ret));
 268                 goto out;
 269         }
 270
 271 out:
 272         if (parent_subvol) {
 273                 free(parent_subvol->path);
 274                 free(parent_subvol);
 275         }
 276         return ret;
 277 }
 278
 279 static int process_mkfile(const char *path, void *user)
 280 {
 281         int ret;
 282         struct btrfs_receive *r = user;
 283         char *full_path = path_cat(r->full_subvol_path, path);
 284
 285         if (g_verbose >= 2)
 286                 fprintf(stderr, "mkfile %s\n", path);
 287
 288         ret = creat(full_path, 0600);
 289         if (ret < 0) {
 290                 ret = -errno;
 291                 fprintf(stderr, "ERROR: mkfile %s failed. %s\n", path,
 292                                 strerror(-ret));
 293                 goto out;
 294         }
 295         close(ret);
 296         ret = 0;
 297
 298 out:
 299         free(full_path);
 300         return ret;
 301 }
 302
 303 static int process_mkdir(const char *path, void *user)
 304 {
 305         int ret;
 306         struct btrfs_receive *r = user;
 307         char *full_path = path_cat(r->full_subvol_path, path);
 308
 309         if (g_verbose >= 2)
 310                 fprintf(stderr, "mkdir %s\n", path);
 311
 312         ret = mkdir(full_path, 0700);
 313         if (ret < 0) {
 314                 ret = -errno;
 315                 fprintf(stderr, "ERROR: mkdir %s failed. %s\n", path,
 316                                 strerror(-ret));
 317         }
 318
 319         free(full_path);
 320         return ret;
 321 }
 322
 323 static int process_mknod(const char *path, u64 mode, u64 dev, void *user)
 324 {
 325         int ret;
 326         struct btrfs_receive *r = user;
 327         char *full_path = path_cat(r->full_subvol_path, path);
 328
 329         if (g_verbose >= 2)
 330                 fprintf(stderr, "mknod %s mode=%llu, dev=%llu\n",
 331                                 path, mode, dev);
 332
 333         ret = mknod(full_path, mode & S_IFMT, dev);
 334         if (ret < 0) {
 335                 ret = -errno;
 336                 fprintf(stderr, "ERROR: mknod %s failed. %s\n", path,
 337                                 strerror(-ret));
 338         }
 339
 340         free(full_path);
 341         return ret;
 342 }
 343
 344 static int process_mkfifo(const char *path, void *user)
 345 {
 346         int ret;
 347         struct btrfs_receive *r = user;
 348         char *full_path = path_cat(r->full_subvol_path, path);
 349
 350         if (g_verbose >= 2)
 351                 fprintf(stderr, "mkfifo %s\n", path);
 352
 353         ret = mkfifo(full_path, 0600);
 354         if (ret < 0) {
 355                 ret = -errno;
 356                 fprintf(stderr, "ERROR: mkfifo %s failed. %s\n", path,
 357                                 strerror(-ret));
 358         }
 359
 360         free(full_path);
 361         return ret;
 362 }
 363
 364 static int process_mksock(const char *path, void *user)
 365 {
 366         int ret;
 367         struct btrfs_receive *r = user;
 368         char *full_path = path_cat(r->full_subvol_path, path);
 369
 370         if (g_verbose >= 2)
 371                 fprintf(stderr, "mksock %s\n", path);
 372
 373         ret = mknod(full_path, 0600 | S_IFSOCK, 0);
 374         if (ret < 0) {
 375                 ret = -errno;
 376                 fprintf(stderr, "ERROR: mknod %s failed. %s\n", path,
 377                                 strerror(-ret));
 378         }
 379
 380         free(full_path);
 381         return ret;
 382 }
 383
 384 static int process_symlink(const char *path, const char *lnk, void *user)
 385 {
 386         int ret;
 387         struct btrfs_receive *r = user;
 388         char *full_path = path_cat(r->full_subvol_path, path);
 389
 390         if (g_verbose >= 2)
 391                 fprintf(stderr, "symlink %s -> %s\n", path, lnk);
 392
 393         ret = symlink(lnk, full_path);
 394         if (ret < 0) {
 395                 ret = -errno;
 396                 fprintf(stderr, "ERROR: symlink %s -> %s failed. %s\n", path,
 397                                 lnk, strerror(-ret));
 398         }
 399
 400         free(full_path);
 401         return ret;
 402 }
 403
 404 static int process_rename(const char *from, const char *to, void *user)
 405 {
 406         int ret;
 407         struct btrfs_receive *r = user;
 408         char *full_from = path_cat(r->full_subvol_path, from);
 409         char *full_to = path_cat(r->full_subvol_path, to);
 410
 411         if (g_verbose >= 2)
 412                 fprintf(stderr, "rename %s -> %s\n", from, to);
 413
 414         ret = rename(full_from, full_to);
 415         if (ret < 0) {
 416                 ret = -errno;
 417                 fprintf(stderr, "ERROR: rename %s -> %s failed. %s\n", from,
 418                                 to, strerror(-ret));
 419         }
 420
 421         free(full_from);
 422         free(full_to);
 423         return ret;
 424 }
 425
 426 static int process_link(const char *path, const char *lnk, void *user)
 427 {
 428         int ret;
 429         struct btrfs_receive *r = user;
 430         char *full_path = path_cat(r->full_subvol_path, path);
 431         char *full_link_path = path_cat(r->full_subvol_path, lnk);
 432
 433         if (g_verbose >= 2)
 434                 fprintf(stderr, "link %s -> %s\n", path, lnk);
 435
 436         ret = link(full_link_path, full_path);
 437         if (ret < 0) {
 438                 ret = -errno;
 439                 fprintf(stderr, "ERROR: link %s -> %s failed. %s\n", path,
 440                                 lnk, strerror(-ret));
 441         }
 442
 443         free(full_path);
 444         free(full_link_path);
 445         return ret;
 446 }
 447
 448
 449 static int process_unlink(const char *path, void *user)
 450 {
 451         int ret;
 452         struct btrfs_receive *r = user;
 453         char *full_path = path_cat(r->full_subvol_path, path);
 454
 455         if (g_verbose >= 2)
 456                 fprintf(stderr, "unlink %s\n", path);
 457
 458         ret = unlink(full_path);
 459         if (ret < 0) {
 460                 ret = -errno;
 461                 fprintf(stderr, "ERROR: unlink %s failed. %s\n", path,
 462                                 strerror(-ret));
 463         }
 464
 465         free(full_path);
 466         return ret;
 467 }
 468
 469 static int process_rmdir(const char *path, void *user)
 470 {
 471         int ret;
 472         struct btrfs_receive *r = user;
 473         char *full_path = path_cat(r->full_subvol_path, path);
 474
 475         if (g_verbose >= 2)
 476                 fprintf(stderr, "rmdir %s\n", path);
 477
 478         ret = rmdir(full_path);
 479         if (ret < 0) {
 480                 ret = -errno;
 481                 fprintf(stderr, "ERROR: rmdir %s failed. %s\n", path,
 482                                 strerror(-ret));
 483         }
 484
 485         free(full_path);
 486         return ret;
 487 }
 488
 489
 490 static int open_inode_for_write(struct btrfs_receive *r, const char *path)
 491 {
 492         int ret = 0;
 493
 494         if (r->write_fd != -1) {
 495                 if (strcmp(r->write_path, path) == 0)
 496                         goto out;
 497                 close(r->write_fd);
 498                 r->write_fd = -1;
 499         }
 500
 501         r->write_fd = open(path, O_RDWR);
 502         if (r->write_fd < 0) {
 503                 ret = -errno;
 504                 fprintf(stderr, "ERROR: open %s failed. %s\n", path,
 505                                 strerror(-ret));
 506                 goto out;
 507         }
 508         free(r->write_path);
 509         r->write_path = strdup(path);
 510
 511 out:
 512         return ret;
 513 }
 514
 515 static int close_inode_for_write(struct btrfs_receive *r)
 516 {
 517         int ret = 0;
 518
 519         if(r->write_fd == -1)
 520                 goto out;
 521
 522         close(r->write_fd);
 523         r->write_fd = -1;
 524         r->write_path[0] = 0;
 525
 526 out:
 527         return ret;
 528 }
 529
 530 static int process_write(const char *path, const void *data, u64 offset,
 531                          u64 len, void *user)
 532 {
 533         int ret = 0;
 534         struct btrfs_receive *r = user;
 535         char *full_path = path_cat(r->full_subvol_path, path);
 536         u64 pos = 0;
 537         int w;
 538
 539         ret = open_inode_for_write(r, full_path);
 540         if (ret < 0)
 541                 goto out;
 542
 543         while (pos < len) {
 544                 w = pwrite(r->write_fd, (char*)data + pos, len - pos,
 545                                 offset + pos);
 546                 if (w < 0) {
 547                         ret = -errno;
 548                         fprintf(stderr, "ERROR: writing to %s failed. %s\n",
 549                                         path, strerror(-ret));
 550                         goto out;
 551                 }
 552                 pos += w;
 553         }
 554
 555 out:
 556         free(full_path);
 557         return ret;
 558 }
 559
 560 static int process_clone(const char *path, u64 offset, u64 len,
 561                          const u8 *clone_uuid, u64 clone_ctransid,
 562                          const char *clone_path, u64 clone_offset,
 563                          void *user)
 564 {
 565         int ret;
 566         struct btrfs_receive *r = user;
 567         struct btrfs_ioctl_clone_range_args clone_args;
 568         struct subvol_info *si = NULL;
 569         char *full_path = path_cat(r->full_subvol_path, path);
 570         char *subvol_path = NULL;
 571         char *full_clone_path = NULL;
 572         int clone_fd = -1;
 573
 574         ret = open_inode_for_write(r, full_path);
 575         if (ret < 0)
 576                 goto out;
 577
 578         si = subvol_uuid_search(&r->sus, 0, clone_uuid, clone_ctransid, NULL,
 579                         subvol_search_by_received_uuid);
 580         if (!si) {
 581                 if (memcmp(clone_uuid, r->cur_subvol->received_uuid,
 582                                 BTRFS_UUID_SIZE) == 0) {
 583                         /* TODO check generation of extent */
 584                         subvol_path = strdup(r->cur_subvol->path);
 585                 } else {
 586                         ret = -ENOENT;
 587                         fprintf(stderr, "ERROR: did not find source subvol.\n");
 588                         goto out;
 589                 }
 590         } else {
 591                 /*if (rs_args.ctransid > rs_args.rtransid) {
 592                         if (!r->force) {
 593                                 ret = -EINVAL;
 594                                 fprintf(stderr, "ERROR: subvolume %s was "
 595                                                 "modified after it was "
 596                                                 "received.\n",
 597                                                 r->subvol_parent_name);
 598                                 goto out;
 599                         } else {
 600                                 fprintf(stderr, "WARNING: subvolume %s was "
 601                                                 "modified after it was "
 602                                                 "received.\n",
 603                                                 r->subvol_parent_name);
 604                         }
 605                 }*/
 606                 subvol_path = strdup(si->path);
 607         }
 608
 609         full_clone_path = path_cat3(r->root_path, subvol_path, clone_path);
 610
 611         clone_fd = open(full_clone_path, O_RDONLY | O_NOATIME);
 612         if (clone_fd < 0) {
 613                 ret = -errno;
 614                 fprintf(stderr, "ERROR: failed to open %s. %s\n",
 615                                 full_clone_path, strerror(-ret));
 616                 goto out;
 617         }
 618
 619         clone_args.src_fd = clone_fd;
 620         clone_args.src_offset = clone_offset;
 621         clone_args.src_length = len;
 622         clone_args.dest_offset = offset;
 623         ret = ioctl(r->write_fd, BTRFS_IOC_CLONE_RANGE, &clone_args);
 624         if (ret) {
 625                 ret = -errno;
 626                 fprintf(stderr, "ERROR: failed to clone extents to %s\n%s\n",
 627                                 path, strerror(-ret));
 628                 goto out;
 629         }
 630
 631 out:
 632         if (si) {
 633                 free(si->path);
 634                 free(si);
 635         }
 636         free(full_path);
 637         free(full_clone_path);
 638         free(subvol_path);
 639         if (clone_fd != -1)
 640                 close(clone_fd);
 641         return ret;
 642 }
 643
 644
 645 static int process_set_xattr(const char *path, const char *name,
 646                              const void *data, int len, void *user)
 647 {
 648         int ret = 0;
 649         struct btrfs_receive *r = user;
 650         char *full_path = path_cat(r->full_subvol_path, path);
 651
 652         if (g_verbose >= 2) {
 653                 fprintf(stderr, "set_xattr %s - name=%s data_len=%d "
 654                                 "data=%.*s\n", path, name, len,
 655                                 len, (char*)data);
 656         }
 657
 658         ret = lsetxattr(full_path, name, data, len, 0);
 659         if (ret < 0) {
 660                 ret = -errno;
 661                 fprintf(stderr, "ERROR: lsetxattr %s %s=%.*s failed. %s\n",
 662                                 path, name, len, (char*)data, strerror(-ret));
 663                 goto out;
 664         }
 665
 666 out:
 667         free(full_path);
 668         return ret;
 669 }
 670
 671 static int process_remove_xattr(const char *path, const char *name, void *user)
 672 {
 673         int ret = 0;
 674         struct btrfs_receive *r = user;
 675         char *full_path = path_cat(r->full_subvol_path, path);
 676
 677         if (g_verbose >= 2) {
 678                 fprintf(stderr, "remove_xattr %s - name=%s\n",
 679                                 path, name);
 680         }
 681
 682         ret = lremovexattr(full_path, name);
 683         if (ret < 0) {
 684                 ret = -errno;
 685                 fprintf(stderr, "ERROR: lremovexattr %s %s failed. %s\n",
 686                                 path, name, strerror(-ret));
 687                 goto out;
 688         }
 689
 690 out:
 691         free(full_path);
 692         return ret;
 693 }
 694
 695 static int process_truncate(const char *path, u64 size, void *user)
 696 {
 697         int ret = 0;
 698         struct btrfs_receive *r = user;
 699         char *full_path = path_cat(r->full_subvol_path, path);
 700
 701         if (g_verbose >= 2)
 702                 fprintf(stderr, "truncate %s size=%llu\n", path, size);
 703
 704         ret = truncate(full_path, size);
 705         if (ret < 0) {
 706                 ret = -errno;
 707                 fprintf(stderr, "ERROR: truncate %s failed. %s\n",
 708                                 path, strerror(-ret));
 709                 goto out;
 710         }
 711
 712 out:
 713         free(full_path);
 714         return ret;
 715 }
 716
 717 static int process_chmod(const char *path, u64 mode, void *user)
 718 {
 719         int ret = 0;
 720         struct btrfs_receive *r = user;
 721         char *full_path = path_cat(r->full_subvol_path, path);
 722
 723         if (g_verbose >= 2)
 724                 fprintf(stderr, "chmod %s - mode=0%o\n", path, (int)mode);
 725
 726         ret = chmod(full_path, mode);
 727         if (ret < 0) {
 728                 ret = -errno;
 729                 fprintf(stderr, "ERROR: chmod %s failed. %s\n",
 730                                 path, strerror(-ret));
 731                 goto out;
 732         }
 733
 734 out:
 735         free(full_path);
 736         return ret;
 737 }
 738
 739 static int process_chown(const char *path, u64 uid, u64 gid, void *user)
 740 {
 741         int ret = 0;
 742         struct btrfs_receive *r = user;
 743         char *full_path = path_cat(r->full_subvol_path, path);
 744
 745         if (g_verbose >= 2)
 746                 fprintf(stderr, "chown %s - uid=%llu, gid=%llu\n", path,
 747                                 uid, gid);
 748
 749         ret = lchown(full_path, uid, gid);
 750         if (ret < 0) {
 751                 ret = -errno;
 752                 fprintf(stderr, "ERROR: chown %s failed. %s\n",
 753                                 path, strerror(-ret));
 754                 goto out;
 755         }
 756
 757 out:
 758         free(full_path);
 759         return ret;
 760 }
 761
 762 static int process_utimes(const char *path, struct timespec *at,
 763                           struct timespec *mt, struct timespec *ct,
 764                           void *user)
 765 {
 766         int ret = 0;
 767         struct btrfs_receive *r = user;
 768         char *full_path = path_cat(r->full_subvol_path, path);
 769         struct timespec tv[2];
 770
 771         if (g_verbose >= 2)
 772                 fprintf(stderr, "utimes %s\n", path);
 773
 774         tv[0] = *at;
 775         tv[1] = *mt;
 776         ret = utimensat(AT_FDCWD, full_path, tv, AT_SYMLINK_NOFOLLOW);
 777         if (ret < 0) {
 778                 ret = -errno;
 779                 fprintf(stderr, "ERROR: utimes %s failed. %s\n",
 780                                 path, strerror(-ret));
 781                 goto out;
 782         }
 783
 784 out:
 785         free(full_path);
 786         return ret;
 787 }
 788
 789
 790 static struct btrfs_send_ops send_ops = {
 791         .subvol = process_subvol,
 792         .snapshot = process_snapshot,
 793         .mkfile = process_mkfile,
 794         .mkdir = process_mkdir,
 795         .mknod = process_mknod,
 796         .mkfifo = process_mkfifo,
 797         .mksock = process_mksock,
 798         .symlink = process_symlink,
 799         .rename = process_rename,
 800         .link = process_link,
 801         .unlink = process_unlink,
 802         .rmdir = process_rmdir,
 803         .write = process_write,
 804         .clone = process_clone,
 805         .set_xattr = process_set_xattr,
 806         .remove_xattr = process_remove_xattr,
 807         .truncate = process_truncate,
 808         .chmod = process_chmod,
 809         .chown = process_chown,
 810         .utimes = process_utimes,
 811 };
 812
 813 static int do_receive(struct btrfs_receive *r, const char *tomnt, int r_fd)
 814 {
 815         int ret;
 816         char *dest_dir_full_path;
 817         int end = 0;
 818
 819         dest_dir_full_path = realpath(tomnt, NULL);
 820         if (!dest_dir_full_path) {
 821                 ret = -errno;
 822                 fprintf(stderr, "ERROR: realpath(%s) failed. %s\n", tomnt,
 823                         strerror(-ret));
 824                 goto out;
 825         }
 826         r->dest_dir_fd = open(dest_dir_full_path, O_RDONLY | O_NOATIME);
 827         if (r->dest_dir_fd < 0) {
 828                 ret = -errno;
 829                 fprintf(stderr,
 830                         "ERROR: failed to open destination directory %s. %s\n",
 831                         dest_dir_full_path, strerror(-ret));
 832                 goto out;
 833         }
 834
 835         ret = find_mount_root(dest_dir_full_path, &r->root_path);
 836         if (ret < 0) {
 837                 ret = -EINVAL;
 838                 fprintf(stderr, "ERROR: failed to determine mount point "
 839                         "for %s\n", dest_dir_full_path);
 840                 goto out;
 841         }
 842         r->mnt_fd = open(r->root_path, O_RDONLY | O_NOATIME);
 843         if (r->mnt_fd < 0) {
 844                 ret = -errno;
 845                 fprintf(stderr, "ERROR: failed to open %s. %s\n", r->root_path,
 846                         strerror(-ret));
 847                 goto out;
 848         }
 849
 850         /*
 851          * find_mount_root returns a root_path that is a subpath of
 852          * dest_dir_full_path. Now get the other part of root_path,
 853          * which is the destination dir relative to root_path.
 854          */
 855         r->dest_dir_path = dest_dir_full_path + strlen(r->root_path);
 856         while (r->dest_dir_path[0] == '/')
 857                 r->dest_dir_path++;
 858
 859         ret = subvol_uuid_search_init(r->mnt_fd, &r->sus);
 860         if (ret < 0)
 861                 goto out;
 862
 863         while (!end) {
 864                 ret = btrfs_read_and_process_send_stream(r_fd, &send_ops, r,
 865                                                          r->honor_end_cmd);
 866                 if (ret < 0)
 867                         goto out;
 868                 if (ret)
 869                         end = 1;
 870
 871                 ret = close_inode_for_write(r);
 872                 if (ret < 0)
 873                         goto out;
 874                 ret = finish_subvol(r);
 875                 if (ret < 0)
 876                         goto out;
 877         }
 878         ret = 0;
 879
 880 out:
 881         if (r->write_fd != -1) {
 882                 close(r->write_fd);
 883                 r->write_fd = -1;
 884         }
 885         free(r->root_path);
 886         r->root_path = NULL;
 887         free(r->write_path);
 888         r->write_path = NULL;
 889         free(r->full_subvol_path);
 890         r->full_subvol_path = NULL;
 891         r->dest_dir_path = NULL;
 892         free(dest_dir_full_path);
 893         if (r->cur_subvol) {
 894                 free(r->cur_subvol->path);
 895                 free(r->cur_subvol);
 896                 r->cur_subvol = NULL;
 897         }
 898         subvol_uuid_search_finit(&r->sus);
 899         if (r->mnt_fd != -1) {
 900                 close(r->mnt_fd);
 901                 r->mnt_fd = -1;
 902         }
 903         if (r->dest_dir_fd != -1) {
 904                 close(r->dest_dir_fd);
 905                 r->dest_dir_fd = -1;
 906         }
 907         return ret;
 908 }
 909
 910 int cmd_receive(int argc, char **argv)
 911 {
 912         int c;
 913         char *tomnt = NULL;
 914         char *fromfile = NULL;
 915         struct btrfs_receive r;
 916         int receive_fd = fileno(stdin);
 917
 918         int ret;
 919
 920         memset(&r, 0, sizeof(r));
 921         r.mnt_fd = -1;
 922         r.write_fd = -1;
 923         r.dest_dir_fd = -1;
 924
 925         while ((c = getopt(argc, argv, "evf:")) != -1) {
 926                 switch (c) {
 927                 case 'v':
 928                         g_verbose++;
 929                         break;
 930                 case 'f':
 931                         fromfile = optarg;
 932                         break;
 933                 case 'e':
 934                         r.honor_end_cmd = 1;
 935                         break;
 936                 case '?':
 937                 default:
 938                         fprintf(stderr, "ERROR: receive args invalid.\n");
 939                         return 1;
 940                 }
 941         }
 942
 943         if (optind + 1 != argc) {
 944                 fprintf(stderr, "ERROR: receive needs path to subvolume\n");
 945                 return 1;
 946         }
 947
 948         tomnt = argv[optind];
 949
 950         if (fromfile) {
 951                 receive_fd = open(fromfile, O_RDONLY | O_NOATIME);
 952                 if (receive_fd < 0) {
 953                         fprintf(stderr, "ERROR: failed to open %s\n", fromfile);
 954                         return -errno;
 955                 }
 956         }
 957
 958         ret = do_receive(&r, tomnt, receive_fd);
 959
 960         return ret;
 961 }
 962
 963 const char * const cmd_receive_usage[] = {
 964         "btrfs receive [-ve] [-f <infile>] <mount>",
 965         "Receive subvolumes from stdin.",
 966         "Receives one or more subvolumes that were previously ",
 967         "sent with btrfs send. The received subvolumes are stored",
 968         "into <mount>.",
 969         "btrfs receive will fail in case a receiving subvolume",
 970         "already exists. It will also fail in case a previously",
 971         "received subvolume was changed after it was received.",
 972         "After receiving a subvolume, it is immediately set to",
 973         "read only.\n",
 974         "-v               Enable verbose debug output. Each",
 975         "                 occurrence of this option increases the",
 976         "                 verbose level more.",
 977         "-f <infile>      By default, btrfs receive uses stdin",
 978         "                 to receive the subvolumes. Use this",
 979         "                 option to specify a file to use instead.",
 980         "-e               Terminate after receiving an <end cmd>",
 981         "                 in the data stream. Without this option,",
 982         "                 the receiver terminates only if an error",
 983         "                 is recognized or on EOF.",
 984         NULL
 985 };