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 #include <getopt.h>
  36
  37 #include <sys/stat.h>
  38 #include <sys/types.h>
  39 #include <sys/ioctl.h>
  40 #include <sys/time.h>
  41 #include <sys/types.h>
  42 #include <sys/xattr.h>
  43 #include <uuid/uuid.h>
  44
  45 #include "ctree.h"
  46 #include "ioctl.h"
  47 #include "commands.h"
  48 #include "utils.h"
  49 #include "list.h"
  50 #include "btrfs-list.h"
  51
  52 #include "send.h"
  53 #include "send-stream.h"
  54 #include "send-utils.h"
  55
  56 static int g_verbose = 0;
  57
  58 struct btrfs_receive
  59 {
  60         int mnt_fd;
  61         int dest_dir_fd;
  62
  63         int write_fd;
  64         char *write_path;
  65
  66         char *root_path;
  67         char *dest_dir_path; /* relative to root_path */
  68         char *full_subvol_path;
  69
  70         struct subvol_info *cur_subvol;
  71
  72         struct subvol_uuid_search sus;
  73
  74         int honor_end_cmd;
  75 };
  76
  77 static int finish_subvol(struct btrfs_receive *r)
  78 {
  79         int ret;
  80         int subvol_fd = -1;
  81         struct btrfs_ioctl_received_subvol_args rs_args;
  82         char uuid_str[BTRFS_UUID_UNPARSED_SIZE];
  83         u64 flags;
  84
  85         if (r->cur_subvol == NULL)
  86                 return 0;
  87
  88         subvol_fd = openat(r->mnt_fd, r->cur_subvol->path,
  89                         O_RDONLY | O_NOATIME);
  90         if (subvol_fd < 0) {
  91                 ret = -errno;
  92                 fprintf(stderr, "ERROR: open %s failed. %s\n",
  93                                 r->cur_subvol->path, strerror(-ret));
  94                 goto out;
  95         }
  96
  97         memset(&rs_args, 0, sizeof(rs_args));
  98         memcpy(rs_args.uuid, r->cur_subvol->received_uuid, BTRFS_UUID_SIZE);
  99         rs_args.stransid = r->cur_subvol->stransid;
 100
 101         if (g_verbose >= 1) {
 102                 uuid_unparse((u8*)rs_args.uuid, uuid_str);
 103                 fprintf(stderr, "BTRFS_IOC_SET_RECEIVED_SUBVOL uuid=%s, "
 104                                 "stransid=%llu\n", uuid_str, rs_args.stransid);
 105         }
 106
 107         ret = ioctl(subvol_fd, BTRFS_IOC_SET_RECEIVED_SUBVOL, &rs_args);
 108         if (ret < 0) {
 109                 ret = -errno;
 110                 fprintf(stderr, "ERROR: BTRFS_IOC_SET_RECEIVED_SUBVOL failed. %s\n",
 111                                 strerror(-ret));
 112                 goto out;
 113         }
 114         r->cur_subvol->rtransid = rs_args.rtransid;
 115
 116         ret = ioctl(subvol_fd, BTRFS_IOC_SUBVOL_GETFLAGS, &flags);
 117         if (ret < 0) {
 118                 ret = -errno;
 119                 fprintf(stderr, "ERROR: BTRFS_IOC_SUBVOL_GETFLAGS failed. %s\n",
 120                                 strerror(-ret));
 121                 goto out;
 122         }
 123
 124         flags |= BTRFS_SUBVOL_RDONLY;
 125
 126         ret = ioctl(subvol_fd, BTRFS_IOC_SUBVOL_SETFLAGS, &flags);
 127         if (ret < 0) {
 128                 ret = -errno;
 129                 fprintf(stderr, "ERROR: failed to make subvolume read only. "
 130                                 "%s\n", strerror(-ret));
 131                 goto out;
 132         }
 133
 134         ret = 0;
 135
 136 out:
 137         if (r->cur_subvol) {
 138                 free(r->cur_subvol->path);
 139                 free(r->cur_subvol);
 140                 r->cur_subvol = NULL;
 141         }
 142         if (subvol_fd != -1)
 143                 close(subvol_fd);
 144         return ret;
 145 }
 146
 147 static int process_subvol(const char *path, const u8 *uuid, u64 ctransid,
 148                           void *user)
 149 {
 150         int ret;
 151         struct btrfs_receive *r = user;
 152         struct btrfs_ioctl_vol_args args_v1;
 153         char uuid_str[BTRFS_UUID_UNPARSED_SIZE];
 154
 155         ret = finish_subvol(r);
 156         if (ret < 0)
 157                 goto out;
 158
 159         r->cur_subvol = calloc(1, sizeof(*r->cur_subvol));
 160
 161         if (strlen(r->dest_dir_path) == 0)
 162                 r->cur_subvol->path = strdup(path);
 163         else
 164                 r->cur_subvol->path = path_cat(r->dest_dir_path, path);
 165         free(r->full_subvol_path);
 166         r->full_subvol_path = path_cat3(r->root_path, r->dest_dir_path, path);
 167
 168         fprintf(stderr, "At subvol %s\n", path);
 169
 170         memcpy(r->cur_subvol->received_uuid, uuid, BTRFS_UUID_SIZE);
 171         r->cur_subvol->stransid = ctransid;
 172
 173         if (g_verbose) {
 174                 uuid_unparse((u8*)r->cur_subvol->received_uuid, uuid_str);
 175                 fprintf(stderr, "receiving subvol %s uuid=%s, stransid=%llu\n",
 176                                 path, uuid_str,
 177                                 r->cur_subvol->stransid);
 178         }
 179
 180         memset(&args_v1, 0, sizeof(args_v1));
 181         strncpy_null(args_v1.name, path);
 182         ret = ioctl(r->dest_dir_fd, BTRFS_IOC_SUBVOL_CREATE, &args_v1);
 183         if (ret < 0) {
 184                 ret = -errno;
 185                 fprintf(stderr, "ERROR: creating subvolume %s failed. "
 186                                 "%s\n", path, strerror(-ret));
 187                 goto out;
 188         }
 189
 190 out:
 191         return ret;
 192 }
 193
 194 static int process_snapshot(const char *path, const u8 *uuid, u64 ctransid,
 195                             const u8 *parent_uuid, u64 parent_ctransid,
 196                             void *user)
 197 {
 198         int ret;
 199         struct btrfs_receive *r = user;
 200         char uuid_str[BTRFS_UUID_UNPARSED_SIZE];
 201         struct btrfs_ioctl_vol_args_v2 args_v2;
 202         struct subvol_info *parent_subvol = NULL;
 203
 204         ret = finish_subvol(r);
 205         if (ret < 0)
 206                 goto out;
 207
 208         r->cur_subvol = calloc(1, sizeof(*r->cur_subvol));
 209
 210         if (strlen(r->dest_dir_path) == 0)
 211                 r->cur_subvol->path = strdup(path);
 212         else
 213                 r->cur_subvol->path = path_cat(r->dest_dir_path, path);
 214         free(r->full_subvol_path);
 215         r->full_subvol_path = path_cat3(r->root_path, r->dest_dir_path, path);
 216
 217         fprintf(stdout, "At snapshot %s\n", path);
 218
 219         memcpy(r->cur_subvol->received_uuid, uuid, BTRFS_UUID_SIZE);
 220         r->cur_subvol->stransid = ctransid;
 221
 222         if (g_verbose) {
 223                 uuid_unparse((u8*)r->cur_subvol->received_uuid, uuid_str);
 224                 fprintf(stderr, "receiving snapshot %s uuid=%s, "
 225                                 "ctransid=%llu ", path, uuid_str,
 226                                 r->cur_subvol->stransid);
 227                 uuid_unparse(parent_uuid, uuid_str);
 228                 fprintf(stderr, "parent_uuid=%s, parent_ctransid=%llu\n",
 229                                 uuid_str, parent_ctransid);
 230         }
 231
 232         memset(&args_v2, 0, sizeof(args_v2));
 233         strncpy_null(args_v2.name, path);
 234
 235         parent_subvol = subvol_uuid_search(&r->sus, 0, parent_uuid,
 236                         parent_ctransid, NULL, subvol_search_by_received_uuid);
 237         if (!parent_subvol) {
 238                 parent_subvol = subvol_uuid_search(&r->sus, 0, parent_uuid,
 239                                 parent_ctransid, NULL, subvol_search_by_uuid);
 240         }
 241         if (!parent_subvol) {
 242                 ret = -ENOENT;
 243                 fprintf(stderr, "ERROR: could not find parent subvolume\n");
 244                 goto out;
 245         }
 246
 247         /*if (rs_args.ctransid > rs_args.rtransid) {
 248                 if (!r->force) {
 249                         ret = -EINVAL;
 250                         fprintf(stderr, "ERROR: subvolume %s was modified after it was received.\n", r->subvol_parent_name);
 251                         goto out;
 252                 } else {
 253                         fprintf(stderr, "WARNING: subvolume %s was modified after it was received.\n", r->subvol_parent_name);
 254                 }
 255         }*/
 256
 257         args_v2.fd = openat(r->mnt_fd, parent_subvol->path,
 258                         O_RDONLY | O_NOATIME);
 259         if (args_v2.fd < 0) {
 260                 ret = -errno;
 261                 if (errno != ENOENT)
 262                         fprintf(stderr, "ERROR: open %s failed. %s\n",
 263                                         parent_subvol->path, strerror(-ret));
 264                 else
 265                         fprintf(stderr,
 266                                 "It seems that you have changed your default "
 267                                 "subvolume or you specify other subvolume to\n"
 268                                 "mount btrfs, try to remount this btrfs filesystem "
 269                                 "with fs tree, and run btrfs receive again!\n");
 270                 goto out;
 271         }
 272
 273         ret = ioctl(r->dest_dir_fd, BTRFS_IOC_SNAP_CREATE_V2, &args_v2);
 274         close(args_v2.fd);
 275         if (ret < 0) {
 276                 ret = -errno;
 277                 fprintf(stderr, "ERROR: creating snapshot %s -> %s "
 278                                 "failed. %s\n", parent_subvol->path,
 279                                 path, strerror(-ret));
 280                 goto out;
 281         }
 282
 283 out:
 284         if (parent_subvol) {
 285                 free(parent_subvol->path);
 286                 free(parent_subvol);
 287         }
 288         return ret;
 289 }
 290
 291 static int process_mkfile(const char *path, void *user)
 292 {
 293         int ret;
 294         struct btrfs_receive *r = user;
 295         char *full_path = path_cat(r->full_subvol_path, path);
 296
 297         if (g_verbose >= 2)
 298                 fprintf(stderr, "mkfile %s\n", path);
 299
 300         ret = creat(full_path, 0600);
 301         if (ret < 0) {
 302                 ret = -errno;
 303                 fprintf(stderr, "ERROR: mkfile %s failed. %s\n", path,
 304                                 strerror(-ret));
 305                 goto out;
 306         }
 307         close(ret);
 308         ret = 0;
 309
 310 out:
 311         free(full_path);
 312         return ret;
 313 }
 314
 315 static int process_mkdir(const char *path, void *user)
 316 {
 317         int ret;
 318         struct btrfs_receive *r = user;
 319         char *full_path = path_cat(r->full_subvol_path, path);
 320
 321         if (g_verbose >= 2)
 322                 fprintf(stderr, "mkdir %s\n", path);
 323
 324         ret = mkdir(full_path, 0700);
 325         if (ret < 0) {
 326                 ret = -errno;
 327                 fprintf(stderr, "ERROR: mkdir %s failed. %s\n", path,
 328                                 strerror(-ret));
 329         }
 330
 331         free(full_path);
 332         return ret;
 333 }
 334
 335 static int process_mknod(const char *path, u64 mode, u64 dev, void *user)
 336 {
 337         int ret;
 338         struct btrfs_receive *r = user;
 339         char *full_path = path_cat(r->full_subvol_path, path);
 340
 341         if (g_verbose >= 2)
 342                 fprintf(stderr, "mknod %s mode=%llu, dev=%llu\n",
 343                                 path, mode, dev);
 344
 345         ret = mknod(full_path, mode & S_IFMT, dev);
 346         if (ret < 0) {
 347                 ret = -errno;
 348                 fprintf(stderr, "ERROR: mknod %s failed. %s\n", path,
 349                                 strerror(-ret));
 350         }
 351
 352         free(full_path);
 353         return ret;
 354 }
 355
 356 static int process_mkfifo(const char *path, void *user)
 357 {
 358         int ret;
 359         struct btrfs_receive *r = user;
 360         char *full_path = path_cat(r->full_subvol_path, path);
 361
 362         if (g_verbose >= 2)
 363                 fprintf(stderr, "mkfifo %s\n", path);
 364
 365         ret = mkfifo(full_path, 0600);
 366         if (ret < 0) {
 367                 ret = -errno;
 368                 fprintf(stderr, "ERROR: mkfifo %s failed. %s\n", path,
 369                                 strerror(-ret));
 370         }
 371
 372         free(full_path);
 373         return ret;
 374 }
 375
 376 static int process_mksock(const char *path, void *user)
 377 {
 378         int ret;
 379         struct btrfs_receive *r = user;
 380         char *full_path = path_cat(r->full_subvol_path, path);
 381
 382         if (g_verbose >= 2)
 383                 fprintf(stderr, "mksock %s\n", path);
 384
 385         ret = mknod(full_path, 0600 | S_IFSOCK, 0);
 386         if (ret < 0) {
 387                 ret = -errno;
 388                 fprintf(stderr, "ERROR: mknod %s failed. %s\n", path,
 389                                 strerror(-ret));
 390         }
 391
 392         free(full_path);
 393         return ret;
 394 }
 395
 396 static int process_symlink(const char *path, const char *lnk, void *user)
 397 {
 398         int ret;
 399         struct btrfs_receive *r = user;
 400         char *full_path = path_cat(r->full_subvol_path, path);
 401
 402         if (g_verbose >= 2)
 403                 fprintf(stderr, "symlink %s -> %s\n", path, lnk);
 404
 405         ret = symlink(lnk, full_path);
 406         if (ret < 0) {
 407                 ret = -errno;
 408                 fprintf(stderr, "ERROR: symlink %s -> %s failed. %s\n", path,
 409                                 lnk, strerror(-ret));
 410         }
 411
 412         free(full_path);
 413         return ret;
 414 }
 415
 416 static int process_rename(const char *from, const char *to, void *user)
 417 {
 418         int ret;
 419         struct btrfs_receive *r = user;
 420         char *full_from = path_cat(r->full_subvol_path, from);
 421         char *full_to = path_cat(r->full_subvol_path, to);
 422
 423         if (g_verbose >= 2)
 424                 fprintf(stderr, "rename %s -> %s\n", from, to);
 425
 426         ret = rename(full_from, full_to);
 427         if (ret < 0) {
 428                 ret = -errno;
 429                 fprintf(stderr, "ERROR: rename %s -> %s failed. %s\n", from,
 430                                 to, strerror(-ret));
 431         }
 432
 433         free(full_from);
 434         free(full_to);
 435         return ret;
 436 }
 437
 438 static int process_link(const char *path, const char *lnk, void *user)
 439 {
 440         int ret;
 441         struct btrfs_receive *r = user;
 442         char *full_path = path_cat(r->full_subvol_path, path);
 443         char *full_link_path = path_cat(r->full_subvol_path, lnk);
 444
 445         if (g_verbose >= 2)
 446                 fprintf(stderr, "link %s -> %s\n", path, lnk);
 447
 448         ret = link(full_link_path, full_path);
 449         if (ret < 0) {
 450                 ret = -errno;
 451                 fprintf(stderr, "ERROR: link %s -> %s failed. %s\n", path,
 452                                 lnk, strerror(-ret));
 453         }
 454
 455         free(full_path);
 456         free(full_link_path);
 457         return ret;
 458 }
 459
 460
 461 static int process_unlink(const char *path, void *user)
 462 {
 463         int ret;
 464         struct btrfs_receive *r = user;
 465         char *full_path = path_cat(r->full_subvol_path, path);
 466
 467         if (g_verbose >= 2)
 468                 fprintf(stderr, "unlink %s\n", path);
 469
 470         ret = unlink(full_path);
 471         if (ret < 0) {
 472                 ret = -errno;
 473                 fprintf(stderr, "ERROR: unlink %s failed. %s\n", path,
 474                                 strerror(-ret));
 475         }
 476
 477         free(full_path);
 478         return ret;
 479 }
 480
 481 static int process_rmdir(const char *path, void *user)
 482 {
 483         int ret;
 484         struct btrfs_receive *r = user;
 485         char *full_path = path_cat(r->full_subvol_path, path);
 486
 487         if (g_verbose >= 2)
 488                 fprintf(stderr, "rmdir %s\n", path);
 489
 490         ret = rmdir(full_path);
 491         if (ret < 0) {
 492                 ret = -errno;
 493                 fprintf(stderr, "ERROR: rmdir %s failed. %s\n", path,
 494                                 strerror(-ret));
 495         }
 496
 497         free(full_path);
 498         return ret;
 499 }
 500
 501
 502 static int open_inode_for_write(struct btrfs_receive *r, const char *path)
 503 {
 504         int ret = 0;
 505
 506         if (r->write_fd != -1) {
 507                 if (strcmp(r->write_path, path) == 0)
 508                         goto out;
 509                 close(r->write_fd);
 510                 r->write_fd = -1;
 511         }
 512
 513         r->write_fd = open(path, O_RDWR);
 514         if (r->write_fd < 0) {
 515                 ret = -errno;
 516                 fprintf(stderr, "ERROR: open %s failed. %s\n", path,
 517                                 strerror(-ret));
 518                 goto out;
 519         }
 520         free(r->write_path);
 521         r->write_path = strdup(path);
 522
 523 out:
 524         return ret;
 525 }
 526
 527 static void close_inode_for_write(struct btrfs_receive *r)
 528 {
 529         if(r->write_fd == -1)
 530                 return;
 531
 532         close(r->write_fd);
 533         r->write_fd = -1;
 534         r->write_path[0] = 0;
 535 }
 536
 537 static int process_write(const char *path, const void *data, u64 offset,
 538                          u64 len, void *user)
 539 {
 540         int ret = 0;
 541         struct btrfs_receive *r = user;
 542         char *full_path = path_cat(r->full_subvol_path, path);
 543         u64 pos = 0;
 544         int w;
 545
 546         ret = open_inode_for_write(r, full_path);
 547         if (ret < 0)
 548                 goto out;
 549
 550         while (pos < len) {
 551                 w = pwrite(r->write_fd, (char*)data + pos, len - pos,
 552                                 offset + pos);
 553                 if (w < 0) {
 554                         ret = -errno;
 555                         fprintf(stderr, "ERROR: writing to %s failed. %s\n",
 556                                         path, strerror(-ret));
 557                         goto out;
 558                 }
 559                 pos += w;
 560         }
 561
 562 out:
 563         free(full_path);
 564         return ret;
 565 }
 566
 567 static int process_clone(const char *path, u64 offset, u64 len,
 568                          const u8 *clone_uuid, u64 clone_ctransid,
 569                          const char *clone_path, u64 clone_offset,
 570                          void *user)
 571 {
 572         int ret;
 573         struct btrfs_receive *r = user;
 574         struct btrfs_ioctl_clone_range_args clone_args;
 575         struct subvol_info *si = NULL;
 576         char *full_path = path_cat(r->full_subvol_path, path);
 577         char *subvol_path = NULL;
 578         char *full_clone_path = NULL;
 579         int clone_fd = -1;
 580
 581         ret = open_inode_for_write(r, full_path);
 582         if (ret < 0)
 583                 goto out;
 584
 585         si = subvol_uuid_search(&r->sus, 0, clone_uuid, clone_ctransid, NULL,
 586                         subvol_search_by_received_uuid);
 587         if (!si) {
 588                 if (memcmp(clone_uuid, r->cur_subvol->received_uuid,
 589                                 BTRFS_UUID_SIZE) == 0) {
 590                         /* TODO check generation of extent */
 591                         subvol_path = strdup(r->cur_subvol->path);
 592                 } else {
 593                         ret = -ENOENT;
 594                         fprintf(stderr, "ERROR: did not find source subvol.\n");
 595                         goto out;
 596                 }
 597         } else {
 598                 /*if (rs_args.ctransid > rs_args.rtransid) {
 599                         if (!r->force) {
 600                                 ret = -EINVAL;
 601                                 fprintf(stderr, "ERROR: subvolume %s was "
 602                                                 "modified after it was "
 603                                                 "received.\n",
 604                                                 r->subvol_parent_name);
 605                                 goto out;
 606                         } else {
 607                                 fprintf(stderr, "WARNING: subvolume %s was "
 608                                                 "modified after it was "
 609                                                 "received.\n",
 610                                                 r->subvol_parent_name);
 611                         }
 612                 }*/
 613                 subvol_path = strdup(si->path);
 614         }
 615
 616         full_clone_path = path_cat3(r->root_path, subvol_path, clone_path);
 617
 618         clone_fd = open(full_clone_path, O_RDONLY | O_NOATIME);
 619         if (clone_fd < 0) {
 620                 ret = -errno;
 621                 fprintf(stderr, "ERROR: failed to open %s. %s\n",
 622                                 full_clone_path, strerror(-ret));
 623                 goto out;
 624         }
 625
 626         clone_args.src_fd = clone_fd;
 627         clone_args.src_offset = clone_offset;
 628         clone_args.src_length = len;
 629         clone_args.dest_offset = offset;
 630         ret = ioctl(r->write_fd, BTRFS_IOC_CLONE_RANGE, &clone_args);
 631         if (ret) {
 632                 ret = -errno;
 633                 fprintf(stderr, "ERROR: failed to clone extents to %s\n%s\n",
 634                                 path, strerror(-ret));
 635                 goto out;
 636         }
 637
 638 out:
 639         if (si) {
 640                 free(si->path);
 641                 free(si);
 642         }
 643         free(full_path);
 644         free(full_clone_path);
 645         free(subvol_path);
 646         if (clone_fd != -1)
 647                 close(clone_fd);
 648         return ret;
 649 }
 650
 651
 652 static int process_set_xattr(const char *path, const char *name,
 653                              const void *data, int len, void *user)
 654 {
 655         int ret = 0;
 656         struct btrfs_receive *r = user;
 657         char *full_path = path_cat(r->full_subvol_path, path);
 658
 659         if (g_verbose >= 2) {
 660                 fprintf(stderr, "set_xattr %s - name=%s data_len=%d "
 661                                 "data=%.*s\n", path, name, len,
 662                                 len, (char*)data);
 663         }
 664
 665         ret = lsetxattr(full_path, name, data, len, 0);
 666         if (ret < 0) {
 667                 ret = -errno;
 668                 fprintf(stderr, "ERROR: lsetxattr %s %s=%.*s failed. %s\n",
 669                                 path, name, len, (char*)data, strerror(-ret));
 670                 goto out;
 671         }
 672
 673 out:
 674         free(full_path);
 675         return ret;
 676 }
 677
 678 static int process_remove_xattr(const char *path, const char *name, void *user)
 679 {
 680         int ret = 0;
 681         struct btrfs_receive *r = user;
 682         char *full_path = path_cat(r->full_subvol_path, path);
 683
 684         if (g_verbose >= 2) {
 685                 fprintf(stderr, "remove_xattr %s - name=%s\n",
 686                                 path, name);
 687         }
 688
 689         ret = lremovexattr(full_path, name);
 690         if (ret < 0) {
 691                 ret = -errno;
 692                 fprintf(stderr, "ERROR: lremovexattr %s %s failed. %s\n",
 693                                 path, name, strerror(-ret));
 694                 goto out;
 695         }
 696
 697 out:
 698         free(full_path);
 699         return ret;
 700 }
 701
 702 static int process_truncate(const char *path, u64 size, void *user)
 703 {
 704         int ret = 0;
 705         struct btrfs_receive *r = user;
 706         char *full_path = path_cat(r->full_subvol_path, path);
 707
 708         if (g_verbose >= 2)
 709                 fprintf(stderr, "truncate %s size=%llu\n", path, size);
 710
 711         ret = truncate(full_path, size);
 712         if (ret < 0) {
 713                 ret = -errno;
 714                 fprintf(stderr, "ERROR: truncate %s failed. %s\n",
 715                                 path, strerror(-ret));
 716                 goto out;
 717         }
 718
 719 out:
 720         free(full_path);
 721         return ret;
 722 }
 723
 724 static int process_chmod(const char *path, u64 mode, void *user)
 725 {
 726         int ret = 0;
 727         struct btrfs_receive *r = user;
 728         char *full_path = path_cat(r->full_subvol_path, path);
 729
 730         if (g_verbose >= 2)
 731                 fprintf(stderr, "chmod %s - mode=0%o\n", path, (int)mode);
 732
 733         ret = chmod(full_path, mode);
 734         if (ret < 0) {
 735                 ret = -errno;
 736                 fprintf(stderr, "ERROR: chmod %s failed. %s\n",
 737                                 path, strerror(-ret));
 738                 goto out;
 739         }
 740
 741 out:
 742         free(full_path);
 743         return ret;
 744 }
 745
 746 static int process_chown(const char *path, u64 uid, u64 gid, void *user)
 747 {
 748         int ret = 0;
 749         struct btrfs_receive *r = user;
 750         char *full_path = path_cat(r->full_subvol_path, path);
 751
 752         if (g_verbose >= 2)
 753                 fprintf(stderr, "chown %s - uid=%llu, gid=%llu\n", path,
 754                                 uid, gid);
 755
 756         ret = lchown(full_path, uid, gid);
 757         if (ret < 0) {
 758                 ret = -errno;
 759                 fprintf(stderr, "ERROR: chown %s failed. %s\n",
 760                                 path, strerror(-ret));
 761                 goto out;
 762         }
 763
 764 out:
 765         free(full_path);
 766         return ret;
 767 }
 768
 769 static int process_utimes(const char *path, struct timespec *at,
 770                           struct timespec *mt, struct timespec *ct,
 771                           void *user)
 772 {
 773         int ret = 0;
 774         struct btrfs_receive *r = user;
 775         char *full_path = path_cat(r->full_subvol_path, path);
 776         struct timespec tv[2];
 777
 778         if (g_verbose >= 2)
 779                 fprintf(stderr, "utimes %s\n", path);
 780
 781         tv[0] = *at;
 782         tv[1] = *mt;
 783         ret = utimensat(AT_FDCWD, full_path, tv, AT_SYMLINK_NOFOLLOW);
 784         if (ret < 0) {
 785                 ret = -errno;
 786                 fprintf(stderr, "ERROR: utimes %s failed. %s\n",
 787                                 path, strerror(-ret));
 788                 goto out;
 789         }
 790
 791 out:
 792         free(full_path);
 793         return ret;
 794 }
 795
 796
 797 static struct btrfs_send_ops send_ops = {
 798         .subvol = process_subvol,
 799         .snapshot = process_snapshot,
 800         .mkfile = process_mkfile,
 801         .mkdir = process_mkdir,
 802         .mknod = process_mknod,
 803         .mkfifo = process_mkfifo,
 804         .mksock = process_mksock,
 805         .symlink = process_symlink,
 806         .rename = process_rename,
 807         .link = process_link,
 808         .unlink = process_unlink,
 809         .rmdir = process_rmdir,
 810         .write = process_write,
 811         .clone = process_clone,
 812         .set_xattr = process_set_xattr,
 813         .remove_xattr = process_remove_xattr,
 814         .truncate = process_truncate,
 815         .chmod = process_chmod,
 816         .chown = process_chown,
 817         .utimes = process_utimes,
 818 };
 819
 820 static int do_receive(struct btrfs_receive *r, const char *tomnt, int r_fd,
 821                       u64 max_errors)
 822 {
 823         int ret;
 824         char *dest_dir_full_path;
 825         int end = 0;
 826
 827         dest_dir_full_path = realpath(tomnt, NULL);
 828         if (!dest_dir_full_path) {
 829                 ret = -errno;
 830                 fprintf(stderr, "ERROR: realpath(%s) failed. %s\n", tomnt,
 831                         strerror(-ret));
 832                 goto out;
 833         }
 834         r->dest_dir_fd = open(dest_dir_full_path, O_RDONLY | O_NOATIME);
 835         if (r->dest_dir_fd < 0) {
 836                 ret = -errno;
 837                 fprintf(stderr,
 838                         "ERROR: failed to open destination directory %s. %s\n",
 839                         dest_dir_full_path, strerror(-ret));
 840                 goto out;
 841         }
 842
 843         ret = find_mount_root(dest_dir_full_path, &r->root_path);
 844         if (ret < 0) {
 845                 fprintf(stderr,
 846                         "ERROR: failed to determine mount point for %s: %s\n",
 847                         dest_dir_full_path, strerror(-ret));
 848                 ret = -EINVAL;
 849                 goto out;
 850         }
 851         if (ret > 0) {
 852                 fprintf(stderr,
 853                         "ERROR: %s doesn't belong to btrfs mount point\n",
 854                         dest_dir_full_path);
 855                 ret = -EINVAL;
 856                 goto out;
 857         }
 858         r->mnt_fd = open(r->root_path, O_RDONLY | O_NOATIME);
 859         if (r->mnt_fd < 0) {
 860                 ret = -errno;
 861                 fprintf(stderr, "ERROR: failed to open %s. %s\n", r->root_path,
 862                         strerror(-ret));
 863                 goto out;
 864         }
 865
 866         /*
 867          * find_mount_root returns a root_path that is a subpath of
 868          * dest_dir_full_path. Now get the other part of root_path,
 869          * which is the destination dir relative to root_path.
 870          */
 871         r->dest_dir_path = dest_dir_full_path + strlen(r->root_path);
 872         while (r->dest_dir_path[0] == '/')
 873                 r->dest_dir_path++;
 874
 875         ret = subvol_uuid_search_init(r->mnt_fd, &r->sus);
 876         if (ret < 0)
 877                 goto out;
 878
 879         while (!end) {
 880                 ret = btrfs_read_and_process_send_stream(r_fd, &send_ops, r,
 881                                                          r->honor_end_cmd,
 882                                                          max_errors);
 883                 if (ret < 0)
 884                         goto out;
 885                 if (ret)
 886                         end = 1;
 887
 888                 close_inode_for_write(r);
 889                 ret = finish_subvol(r);
 890                 if (ret < 0)
 891                         goto out;
 892         }
 893         ret = 0;
 894
 895 out:
 896         if (r->write_fd != -1) {
 897                 close(r->write_fd);
 898                 r->write_fd = -1;
 899         }
 900         free(r->root_path);
 901         r->root_path = NULL;
 902         free(r->write_path);
 903         r->write_path = NULL;
 904         free(r->full_subvol_path);
 905         r->full_subvol_path = NULL;
 906         r->dest_dir_path = NULL;
 907         free(dest_dir_full_path);
 908         if (r->cur_subvol) {
 909                 free(r->cur_subvol->path);
 910                 free(r->cur_subvol);
 911                 r->cur_subvol = NULL;
 912         }
 913         subvol_uuid_search_finit(&r->sus);
 914         if (r->mnt_fd != -1) {
 915                 close(r->mnt_fd);
 916                 r->mnt_fd = -1;
 917         }
 918         if (r->dest_dir_fd != -1) {
 919                 close(r->dest_dir_fd);
 920                 r->dest_dir_fd = -1;
 921         }
 922         return ret;
 923 }
 924
 925 static const struct option long_opts[] = {
 926         { "max-errors", 1, NULL, 'E' },
 927         { NULL, 0, NULL, 0 }
 928 };
 929
 930 int cmd_receive(int argc, char **argv)
 931 {
 932         int c;
 933         char *tomnt = NULL;
 934         char *fromfile = NULL;
 935         struct btrfs_receive r;
 936         int receive_fd = fileno(stdin);
 937         u64 max_errors = 1;
 938         int ret;
 939
 940         memset(&r, 0, sizeof(r));
 941         r.mnt_fd = -1;
 942         r.write_fd = -1;
 943         r.dest_dir_fd = -1;
 944
 945         while ((c = getopt_long(argc, argv, "evf:", long_opts, NULL)) != -1) {
 946                 switch (c) {
 947                 case 'v':
 948                         g_verbose++;
 949                         break;
 950                 case 'f':
 951                         fromfile = optarg;
 952                         break;
 953                 case 'e':
 954                         r.honor_end_cmd = 1;
 955                         break;
 956                 case 'E':
 957                         max_errors = arg_strtou64(optarg);
 958                         break;
 959                 case '?':
 960                 default:
 961                         fprintf(stderr, "ERROR: receive args invalid.\n");
 962                         return 1;
 963                 }
 964         }
 965
 966         if (check_argc_exact(argc - optind, 1))
 967                 usage(cmd_receive_usage);
 968
 969         tomnt = argv[optind];
 970
 971         if (fromfile) {
 972                 receive_fd = open(fromfile, O_RDONLY | O_NOATIME);
 973                 if (receive_fd < 0) {
 974                         fprintf(stderr, "ERROR: failed to open %s\n", fromfile);
 975                         return 1;
 976                 }
 977         }
 978
 979         ret = do_receive(&r, tomnt, receive_fd, max_errors);
 980
 981         return !!ret;
 982 }
 983
 984 const char * const cmd_receive_usage[] = {
 985         "btrfs receive [-ve] [-f <infile>] [--max-errors <N>] <mount>",
 986         "Receive subvolumes from stdin.",
 987         "Receives one or more subvolumes that were previously",
 988         "sent with btrfs send. The received subvolumes are stored",
 989         "into <mount>.",
 990         "btrfs receive will fail in case a receiving subvolume",
 991         "already exists. It will also fail in case a previously",
 992         "received subvolume was changed after it was received.",
 993         "After receiving a subvolume, it is immediately set to",
 994         "read only.\n",
 995         "-v               Enable verbose debug output. Each",
 996         "                 occurrence of this option increases the",
 997         "                 verbose level more.",
 998         "-f <infile>      By default, btrfs receive uses stdin",
 999         "                 to receive the subvolumes. Use this",
1000         "                 option to specify a file to use instead.",
1001         "-e               Terminate after receiving an <end cmd>",
1002         "                 in the data stream. Without this option,",
1003         "                 the receiver terminates only if an error",
1004         "                 is recognized or on EOF.",
1005         "--max-errors <N> Terminate as soon as N errors happened while",
1006         "                 processing commands from the send stream.",
1007         "                 Default value is 1. A value of 0 means no limit.",
1008         NULL
1009 };