1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or https://opensource.org/licenses/CDDL-1.0. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved. 24 * Copyright 2015 Nexenta Systems, Inc. All rights reserved. 25 * Copyright (c) 2015, 2018 by Delphix. All rights reserved. 26 * Copyright 2016 Joyent, Inc. 27 * Copyright 2016 Igor Kozhukhov <ikozhukhov@gmail.com> 28 */ 29 30 /* 31 * zfs diff support 32 */ 33 #include <ctype.h> 34 #include <errno.h> 35 #include <libintl.h> 36 #include <string.h> 37 #include <sys/types.h> 38 #include <sys/stat.h> 39 #include <fcntl.h> 40 #include <stddef.h> 41 #include <unistd.h> 42 #include <stdio.h> 43 #include <stdlib.h> 44 #include <pthread.h> 45 #include <sys/zfs_ioctl.h> 46 #include <libzfs.h> 47 #include "libzfs_impl.h" 48 49 #define ZDIFF_SNAPDIR "/.zfs/snapshot/" 50 #define ZDIFF_PREFIX "zfs-diff-%d" 51 52 #define ZDIFF_ADDED '+' 53 #define ZDIFF_MODIFIED "M" 54 #define ZDIFF_REMOVED '-' 55 #define ZDIFF_RENAMED "R" 56 57 58 /* 59 * Given a {dsname, object id}, get the object path 60 */ 61 static int 62 get_stats_for_obj(differ_info_t *di, const char *dsname, uint64_t obj, 63 char *pn, int maxlen, zfs_stat_t *sb) 64 { 65 zfs_cmd_t zc = {"\0"}; 66 int error; 67 68 (void) strlcpy(zc.zc_name, dsname, sizeof (zc.zc_name)); 69 zc.zc_obj = obj; 70 71 errno = 0; 72 error = zfs_ioctl(di->zhp->zfs_hdl, ZFS_IOC_OBJ_TO_STATS, &zc); 73 di->zerr = errno; 74 75 /* we can get stats even if we failed to get a path */ 76 (void) memcpy(sb, &zc.zc_stat, sizeof (zfs_stat_t)); 77 if (error == 0) { 78 ASSERT(di->zerr == 0); 79 (void) strlcpy(pn, zc.zc_value, maxlen); 80 return (0); 81 } 82 83 if (di->zerr == ESTALE) { 84 (void) snprintf(pn, maxlen, "(on_delete_queue)"); 85 return (0); 86 } else if (di->zerr == EPERM) { 87 (void) snprintf(di->errbuf, sizeof (di->errbuf), 88 dgettext(TEXT_DOMAIN, 89 "The sys_config privilege or diff delegated permission " 90 "is needed\nto discover path names")); 91 return (-1); 92 } else if (di->zerr == EACCES) { 93 (void) snprintf(di->errbuf, sizeof (di->errbuf), 94 dgettext(TEXT_DOMAIN, 95 "Key must be loaded to discover path names")); 96 return (-1); 97 } else { 98 (void) snprintf(di->errbuf, sizeof (di->errbuf), 99 dgettext(TEXT_DOMAIN, 100 "Unable to determine path or stats for " 101 "object %lld in %s"), (longlong_t)obj, dsname); 102 return (-1); 103 } 104 } 105 106 /* 107 * stream_bytes 108 * 109 * Prints a file name out a character at a time. If the character is 110 * not in the range of what we consider "printable" ASCII, display it 111 * as an escaped 4-digit octal value. ASCII values less than a space 112 * are all control characters and we declare the upper end as the 113 * DELete character. This also is the last 7-bit ASCII character. 114 * We choose to treat all 8-bit ASCII as not printable for this 115 * application. 116 */ 117 static void 118 stream_bytes(FILE *fp, const char *string) 119 { 120 char c; 121 122 while ((c = *string++) != '\0') { 123 if (c > ' ' && c != '\\' && c < '\177') { 124 (void) fputc(c, fp); 125 } else { 126 (void) fprintf(fp, "\\%04hho", (uint8_t)c); 127 } 128 } 129 } 130 131 static char 132 get_what(mode_t what) 133 { 134 switch (what & S_IFMT) { 135 case S_IFBLK: 136 return ('B'); 137 case S_IFCHR: 138 return ('C'); 139 case S_IFDIR: 140 return ('/'); 141 #ifdef S_IFDOOR 142 case S_IFDOOR: 143 return ('>'); 144 #endif 145 case S_IFIFO: 146 return ('|'); 147 case S_IFLNK: 148 return ('@'); 149 #ifdef S_IFPORT 150 case S_IFPORT: 151 return ('P'); 152 #endif 153 case S_IFSOCK: 154 return ('='); 155 case S_IFREG: 156 return ('F'); 157 default: 158 return ('?'); 159 } 160 } 161 162 static void 163 print_cmn(FILE *fp, differ_info_t *di, const char *file) 164 { 165 if (!di->no_mangle) { 166 stream_bytes(fp, di->dsmnt); 167 stream_bytes(fp, file); 168 } else { 169 (void) fputs(di->dsmnt, fp); 170 (void) fputs(file, fp); 171 } 172 } 173 174 static void 175 print_rename(FILE *fp, differ_info_t *di, const char *old, const char *new, 176 zfs_stat_t *isb) 177 { 178 if (di->timestamped) 179 (void) fprintf(fp, "%10lld.%09lld\t", 180 (longlong_t)isb->zs_ctime[0], 181 (longlong_t)isb->zs_ctime[1]); 182 (void) fputs(ZDIFF_RENAMED "\t", fp); 183 if (di->classify) 184 (void) fprintf(fp, "%c\t", get_what(isb->zs_mode)); 185 print_cmn(fp, di, old); 186 (void) fputs(di->scripted ? "\t" : " -> ", fp); 187 print_cmn(fp, di, new); 188 (void) fputc('\n', fp); 189 } 190 191 static void 192 print_link_change(FILE *fp, differ_info_t *di, int delta, const char *file, 193 zfs_stat_t *isb) 194 { 195 if (di->timestamped) 196 (void) fprintf(fp, "%10lld.%09lld\t", 197 (longlong_t)isb->zs_ctime[0], 198 (longlong_t)isb->zs_ctime[1]); 199 (void) fputs(ZDIFF_MODIFIED "\t", fp); 200 if (di->classify) 201 (void) fprintf(fp, "%c\t", get_what(isb->zs_mode)); 202 print_cmn(fp, di, file); 203 (void) fprintf(fp, "\t(%+d)\n", delta); 204 } 205 206 static void 207 print_file(FILE *fp, differ_info_t *di, char type, const char *file, 208 zfs_stat_t *isb) 209 { 210 if (di->timestamped) 211 (void) fprintf(fp, "%10lld.%09lld\t", 212 (longlong_t)isb->zs_ctime[0], 213 (longlong_t)isb->zs_ctime[1]); 214 (void) fprintf(fp, "%c\t", type); 215 if (di->classify) 216 (void) fprintf(fp, "%c\t", get_what(isb->zs_mode)); 217 print_cmn(fp, di, file); 218 (void) fputc('\n', fp); 219 } 220 221 static int 222 write_inuse_diffs_one(FILE *fp, differ_info_t *di, uint64_t dobj) 223 { 224 struct zfs_stat fsb, tsb; 225 mode_t fmode, tmode; 226 char fobjname[MAXPATHLEN], tobjname[MAXPATHLEN]; 227 boolean_t already_logged = B_FALSE; 228 int fobjerr, tobjerr; 229 int change; 230 231 if (dobj == di->shares) 232 return (0); 233 234 /* 235 * Check the from and to snapshots for info on the object. If 236 * we get ENOENT, then the object just didn't exist in that 237 * snapshot. If we get ENOTSUP, then we tried to get 238 * info on a non-ZPL object, which we don't care about anyway. 239 * For any other error we print a warning which includes the 240 * errno and continue. 241 */ 242 243 fobjerr = get_stats_for_obj(di, di->fromsnap, dobj, fobjname, 244 MAXPATHLEN, &fsb); 245 if (fobjerr && di->zerr != ENOTSUP && di->zerr != ENOENT) { 246 zfs_error_aux(di->zhp->zfs_hdl, "%s", strerror(di->zerr)); 247 zfs_error(di->zhp->zfs_hdl, di->zerr, di->errbuf); 248 /* 249 * Let's not print an error for the same object more than 250 * once if it happens in both snapshots 251 */ 252 already_logged = B_TRUE; 253 } 254 255 tobjerr = get_stats_for_obj(di, di->tosnap, dobj, tobjname, 256 MAXPATHLEN, &tsb); 257 258 if (tobjerr && di->zerr != ENOTSUP && di->zerr != ENOENT) { 259 if (!already_logged) { 260 zfs_error_aux(di->zhp->zfs_hdl, 261 "%s", strerror(di->zerr)); 262 zfs_error(di->zhp->zfs_hdl, di->zerr, di->errbuf); 263 } 264 } 265 /* 266 * Unallocated object sharing the same meta dnode block 267 */ 268 if (fobjerr && tobjerr) { 269 di->zerr = 0; 270 return (0); 271 } 272 273 di->zerr = 0; /* negate get_stats_for_obj() from side that failed */ 274 fmode = fsb.zs_mode & S_IFMT; 275 tmode = tsb.zs_mode & S_IFMT; 276 if (fmode == S_IFDIR || tmode == S_IFDIR || fsb.zs_links == 0 || 277 tsb.zs_links == 0) 278 change = 0; 279 else 280 change = tsb.zs_links - fsb.zs_links; 281 282 if (fobjerr) { 283 if (change) { 284 print_link_change(fp, di, change, tobjname, &tsb); 285 return (0); 286 } 287 print_file(fp, di, ZDIFF_ADDED, tobjname, &tsb); 288 return (0); 289 } else if (tobjerr) { 290 if (change) { 291 print_link_change(fp, di, change, fobjname, &fsb); 292 return (0); 293 } 294 print_file(fp, di, ZDIFF_REMOVED, fobjname, &fsb); 295 return (0); 296 } 297 298 if (fmode != tmode && fsb.zs_gen == tsb.zs_gen) 299 tsb.zs_gen++; /* Force a generational difference */ 300 301 /* Simple modification or no change */ 302 if (fsb.zs_gen == tsb.zs_gen) { 303 /* No apparent changes. Could we assert !this? */ 304 if (fsb.zs_ctime[0] == tsb.zs_ctime[0] && 305 fsb.zs_ctime[1] == tsb.zs_ctime[1]) 306 return (0); 307 if (change) { 308 print_link_change(fp, di, change, 309 change > 0 ? fobjname : tobjname, &tsb); 310 } else if (strcmp(fobjname, tobjname) == 0) { 311 print_file(fp, di, *ZDIFF_MODIFIED, fobjname, &tsb); 312 } else { 313 print_rename(fp, di, fobjname, tobjname, &tsb); 314 } 315 return (0); 316 } else { 317 /* file re-created or object re-used */ 318 print_file(fp, di, ZDIFF_REMOVED, fobjname, &fsb); 319 print_file(fp, di, ZDIFF_ADDED, tobjname, &tsb); 320 return (0); 321 } 322 } 323 324 static int 325 write_inuse_diffs(FILE *fp, differ_info_t *di, dmu_diff_record_t *dr) 326 { 327 uint64_t o; 328 int err; 329 330 for (o = dr->ddr_first; o <= dr->ddr_last; o++) { 331 if ((err = write_inuse_diffs_one(fp, di, o)) != 0) 332 return (err); 333 } 334 return (0); 335 } 336 337 static int 338 describe_free(FILE *fp, differ_info_t *di, uint64_t object, char *namebuf, 339 int maxlen) 340 { 341 struct zfs_stat sb; 342 343 (void) get_stats_for_obj(di, di->fromsnap, object, namebuf, 344 maxlen, &sb); 345 346 /* Don't print if in the delete queue on from side */ 347 if (di->zerr == ESTALE || di->zerr == ENOENT) { 348 di->zerr = 0; 349 return (0); 350 } 351 352 print_file(fp, di, ZDIFF_REMOVED, namebuf, &sb); 353 return (0); 354 } 355 356 static int 357 write_free_diffs(FILE *fp, differ_info_t *di, dmu_diff_record_t *dr) 358 { 359 zfs_cmd_t zc = {"\0"}; 360 libzfs_handle_t *lhdl = di->zhp->zfs_hdl; 361 char fobjname[MAXPATHLEN]; 362 363 (void) strlcpy(zc.zc_name, di->fromsnap, sizeof (zc.zc_name)); 364 zc.zc_obj = dr->ddr_first - 1; 365 366 ASSERT(di->zerr == 0); 367 368 while (zc.zc_obj < dr->ddr_last) { 369 int err; 370 371 err = zfs_ioctl(lhdl, ZFS_IOC_NEXT_OBJ, &zc); 372 if (err == 0) { 373 if (zc.zc_obj == di->shares) { 374 zc.zc_obj++; 375 continue; 376 } 377 if (zc.zc_obj > dr->ddr_last) { 378 break; 379 } 380 (void) describe_free(fp, di, zc.zc_obj, fobjname, 381 MAXPATHLEN); 382 } else if (errno == ESRCH) { 383 break; 384 } else { 385 (void) snprintf(di->errbuf, sizeof (di->errbuf), 386 dgettext(TEXT_DOMAIN, 387 "next allocated object (> %lld) find failure"), 388 (longlong_t)zc.zc_obj); 389 di->zerr = errno; 390 break; 391 } 392 } 393 if (di->zerr) 394 return (-1); 395 return (0); 396 } 397 398 static void * 399 differ(void *arg) 400 { 401 differ_info_t *di = arg; 402 dmu_diff_record_t dr; 403 FILE *ofp; 404 int err = 0; 405 406 if ((ofp = fdopen(di->outputfd, "w")) == NULL) { 407 di->zerr = errno; 408 strlcpy(di->errbuf, strerror(errno), sizeof (di->errbuf)); 409 (void) close(di->datafd); 410 return ((void *)-1); 411 } 412 413 for (;;) { 414 char *cp = (char *)&dr; 415 int len = sizeof (dr); 416 int rv; 417 418 do { 419 rv = read(di->datafd, cp, len); 420 cp += rv; 421 len -= rv; 422 } while (len > 0 && rv > 0); 423 424 if (rv < 0 || (rv == 0 && len != sizeof (dr))) { 425 di->zerr = EPIPE; 426 break; 427 } else if (rv == 0) { 428 /* end of file at a natural breaking point */ 429 break; 430 } 431 432 switch (dr.ddr_type) { 433 case DDR_FREE: 434 err = write_free_diffs(ofp, di, &dr); 435 break; 436 case DDR_INUSE: 437 err = write_inuse_diffs(ofp, di, &dr); 438 break; 439 default: 440 di->zerr = EPIPE; 441 break; 442 } 443 444 if (err || di->zerr) 445 break; 446 } 447 448 (void) fclose(ofp); 449 (void) close(di->datafd); 450 if (err) 451 return ((void *)-1); 452 if (di->zerr) { 453 ASSERT(di->zerr == EPIPE); 454 (void) snprintf(di->errbuf, sizeof (di->errbuf), 455 dgettext(TEXT_DOMAIN, 456 "Internal error: bad data from diff IOCTL")); 457 return ((void *)-1); 458 } 459 return ((void *)0); 460 } 461 462 static int 463 make_temp_snapshot(differ_info_t *di) 464 { 465 libzfs_handle_t *hdl = di->zhp->zfs_hdl; 466 zfs_cmd_t zc = {"\0"}; 467 468 (void) snprintf(zc.zc_value, sizeof (zc.zc_value), 469 ZDIFF_PREFIX, getpid()); 470 (void) strlcpy(zc.zc_name, di->ds, sizeof (zc.zc_name)); 471 zc.zc_cleanup_fd = di->cleanupfd; 472 473 if (zfs_ioctl(hdl, ZFS_IOC_TMP_SNAPSHOT, &zc) != 0) { 474 int err = errno; 475 if (err == EPERM) { 476 (void) snprintf(di->errbuf, sizeof (di->errbuf), 477 dgettext(TEXT_DOMAIN, "The diff delegated " 478 "permission is needed in order\nto create a " 479 "just-in-time snapshot for diffing\n")); 480 return (zfs_error(hdl, EZFS_DIFF, di->errbuf)); 481 } else { 482 (void) snprintf(di->errbuf, sizeof (di->errbuf), 483 dgettext(TEXT_DOMAIN, "Cannot create just-in-time " 484 "snapshot of '%s'"), zc.zc_name); 485 return (zfs_standard_error(hdl, err, di->errbuf)); 486 } 487 } 488 489 di->tmpsnap = zfs_strdup(hdl, zc.zc_value); 490 di->tosnap = zfs_asprintf(hdl, "%s@%s", di->ds, di->tmpsnap); 491 return (0); 492 } 493 494 static void 495 teardown_differ_info(differ_info_t *di) 496 { 497 free(di->ds); 498 free(di->dsmnt); 499 free(di->fromsnap); 500 free(di->frommnt); 501 free(di->tosnap); 502 free(di->tmpsnap); 503 free(di->tomnt); 504 (void) close(di->cleanupfd); 505 } 506 507 static int 508 get_snapshot_names(differ_info_t *di, const char *fromsnap, 509 const char *tosnap) 510 { 511 libzfs_handle_t *hdl = di->zhp->zfs_hdl; 512 char *atptrf = NULL; 513 char *atptrt = NULL; 514 int fdslen, fsnlen; 515 int tdslen, tsnlen; 516 517 /* 518 * Can accept 519 * fdslen fsnlen tdslen tsnlen 520 * dataset@snap1 521 * 0. dataset@snap1 dataset@snap2 >0 >1 >0 >1 522 * 1. dataset@snap1 @snap2 >0 >1 ==0 >1 523 * 2. dataset@snap1 dataset >0 >1 >0 ==0 524 * 3. @snap1 dataset@snap2 ==0 >1 >0 >1 525 * 4. @snap1 dataset ==0 >1 >0 ==0 526 */ 527 if (tosnap == NULL) { 528 /* only a from snapshot given, must be valid */ 529 (void) snprintf(di->errbuf, sizeof (di->errbuf), 530 dgettext(TEXT_DOMAIN, 531 "Badly formed snapshot name %s"), fromsnap); 532 533 if (!zfs_validate_name(hdl, fromsnap, ZFS_TYPE_SNAPSHOT, 534 B_FALSE)) { 535 return (zfs_error(hdl, EZFS_INVALIDNAME, 536 di->errbuf)); 537 } 538 539 atptrf = strchr(fromsnap, '@'); 540 ASSERT(atptrf != NULL); 541 fdslen = atptrf - fromsnap; 542 543 di->fromsnap = zfs_strdup(hdl, fromsnap); 544 di->ds = zfs_strdup(hdl, fromsnap); 545 di->ds[fdslen] = '\0'; 546 547 /* the to snap will be a just-in-time snap of the head */ 548 return (make_temp_snapshot(di)); 549 } 550 551 (void) snprintf(di->errbuf, sizeof (di->errbuf), 552 dgettext(TEXT_DOMAIN, 553 "Unable to determine which snapshots to compare")); 554 555 atptrf = strchr(fromsnap, '@'); 556 atptrt = strchr(tosnap, '@'); 557 fdslen = atptrf ? atptrf - fromsnap : strlen(fromsnap); 558 tdslen = atptrt ? atptrt - tosnap : strlen(tosnap); 559 fsnlen = strlen(fromsnap) - fdslen; /* includes @ sign */ 560 tsnlen = strlen(tosnap) - tdslen; /* includes @ sign */ 561 562 if (fsnlen <= 1 || tsnlen == 1 || (fdslen == 0 && tdslen == 0)) { 563 return (zfs_error(hdl, EZFS_INVALIDNAME, di->errbuf)); 564 } else if ((fdslen > 0 && tdslen > 0) && 565 ((tdslen != fdslen || strncmp(fromsnap, tosnap, fdslen) != 0))) { 566 /* 567 * not the same dataset name, might be okay if 568 * tosnap is a clone of a fromsnap descendant. 569 */ 570 char origin[ZFS_MAX_DATASET_NAME_LEN]; 571 zprop_source_t src; 572 zfs_handle_t *zhp; 573 574 di->ds = zfs_alloc(di->zhp->zfs_hdl, tdslen + 1); 575 (void) strlcpy(di->ds, tosnap, tdslen + 1); 576 577 zhp = zfs_open(hdl, di->ds, ZFS_TYPE_FILESYSTEM); 578 while (zhp != NULL) { 579 if (zfs_prop_get(zhp, ZFS_PROP_ORIGIN, origin, 580 sizeof (origin), &src, NULL, 0, B_FALSE) != 0) { 581 (void) zfs_close(zhp); 582 zhp = NULL; 583 break; 584 } 585 if (strncmp(origin, fromsnap, fsnlen) == 0) 586 break; 587 588 (void) zfs_close(zhp); 589 zhp = zfs_open(hdl, origin, ZFS_TYPE_FILESYSTEM); 590 } 591 592 if (zhp == NULL) { 593 (void) snprintf(di->errbuf, sizeof (di->errbuf), 594 dgettext(TEXT_DOMAIN, 595 "Not an earlier snapshot from the same fs")); 596 return (zfs_error(hdl, EZFS_INVALIDNAME, di->errbuf)); 597 } else { 598 (void) zfs_close(zhp); 599 } 600 601 di->isclone = B_TRUE; 602 di->fromsnap = zfs_strdup(hdl, fromsnap); 603 if (tsnlen) 604 di->tosnap = zfs_strdup(hdl, tosnap); 605 else 606 return (make_temp_snapshot(di)); 607 } else { 608 int dslen = fdslen ? fdslen : tdslen; 609 610 di->ds = zfs_alloc(hdl, dslen + 1); 611 (void) strlcpy(di->ds, fdslen ? fromsnap : tosnap, dslen + 1); 612 613 di->fromsnap = zfs_asprintf(hdl, "%s%s", di->ds, atptrf); 614 if (tsnlen) { 615 di->tosnap = zfs_asprintf(hdl, "%s%s", di->ds, atptrt); 616 } else { 617 return (make_temp_snapshot(di)); 618 } 619 } 620 return (0); 621 } 622 623 static int 624 get_mountpoint(differ_info_t *di, char *dsnm, char **mntpt) 625 { 626 boolean_t mounted; 627 628 mounted = is_mounted(di->zhp->zfs_hdl, dsnm, mntpt); 629 if (mounted == B_FALSE) { 630 (void) snprintf(di->errbuf, sizeof (di->errbuf), 631 dgettext(TEXT_DOMAIN, 632 "Cannot diff an unmounted snapshot")); 633 return (zfs_error(di->zhp->zfs_hdl, EZFS_BADTYPE, di->errbuf)); 634 } 635 636 /* Avoid a double slash at the beginning of root-mounted datasets */ 637 if (**mntpt == '/' && *(*mntpt + 1) == '\0') 638 **mntpt = '\0'; 639 return (0); 640 } 641 642 static int 643 get_mountpoints(differ_info_t *di) 644 { 645 char *strptr; 646 char *frommntpt; 647 648 /* 649 * first get the mountpoint for the parent dataset 650 */ 651 if (get_mountpoint(di, di->ds, &di->dsmnt) != 0) 652 return (-1); 653 654 strptr = strchr(di->tosnap, '@'); 655 ASSERT3P(strptr, !=, NULL); 656 di->tomnt = zfs_asprintf(di->zhp->zfs_hdl, "%s%s%s", di->dsmnt, 657 ZDIFF_SNAPDIR, ++strptr); 658 659 strptr = strchr(di->fromsnap, '@'); 660 ASSERT3P(strptr, !=, NULL); 661 662 frommntpt = di->dsmnt; 663 if (di->isclone) { 664 char *mntpt; 665 int err; 666 667 *strptr = '\0'; 668 err = get_mountpoint(di, di->fromsnap, &mntpt); 669 *strptr = '@'; 670 if (err != 0) 671 return (-1); 672 frommntpt = mntpt; 673 } 674 675 di->frommnt = zfs_asprintf(di->zhp->zfs_hdl, "%s%s%s", frommntpt, 676 ZDIFF_SNAPDIR, ++strptr); 677 678 if (di->isclone) 679 free(frommntpt); 680 681 return (0); 682 } 683 684 static int 685 setup_differ_info(zfs_handle_t *zhp, const char *fromsnap, 686 const char *tosnap, differ_info_t *di) 687 { 688 di->zhp = zhp; 689 690 di->cleanupfd = open(ZFS_DEV, O_RDWR | O_CLOEXEC); 691 VERIFY(di->cleanupfd >= 0); 692 693 if (get_snapshot_names(di, fromsnap, tosnap) != 0) 694 return (-1); 695 696 if (get_mountpoints(di) != 0) 697 return (-1); 698 699 if (find_shares_object(di) != 0) 700 return (-1); 701 702 return (0); 703 } 704 705 int 706 zfs_show_diffs(zfs_handle_t *zhp, int outfd, const char *fromsnap, 707 const char *tosnap, int flags) 708 { 709 zfs_cmd_t zc = {"\0"}; 710 char errbuf[ERRBUFLEN]; 711 differ_info_t di = { 0 }; 712 pthread_t tid; 713 int pipefd[2]; 714 int iocerr; 715 716 (void) snprintf(errbuf, sizeof (errbuf), 717 dgettext(TEXT_DOMAIN, "zfs diff failed")); 718 719 if (setup_differ_info(zhp, fromsnap, tosnap, &di)) { 720 teardown_differ_info(&di); 721 return (-1); 722 } 723 724 if (pipe2(pipefd, O_CLOEXEC)) { 725 zfs_error_aux(zhp->zfs_hdl, "%s", strerror(errno)); 726 teardown_differ_info(&di); 727 return (zfs_error(zhp->zfs_hdl, EZFS_PIPEFAILED, errbuf)); 728 } 729 730 di.scripted = (flags & ZFS_DIFF_PARSEABLE); 731 di.classify = (flags & ZFS_DIFF_CLASSIFY); 732 di.timestamped = (flags & ZFS_DIFF_TIMESTAMP); 733 di.no_mangle = (flags & ZFS_DIFF_NO_MANGLE); 734 735 di.outputfd = outfd; 736 di.datafd = pipefd[0]; 737 738 if (pthread_create(&tid, NULL, differ, &di)) { 739 zfs_error_aux(zhp->zfs_hdl, "%s", strerror(errno)); 740 (void) close(pipefd[0]); 741 (void) close(pipefd[1]); 742 teardown_differ_info(&di); 743 return (zfs_error(zhp->zfs_hdl, 744 EZFS_THREADCREATEFAILED, errbuf)); 745 } 746 747 /* do the ioctl() */ 748 (void) strlcpy(zc.zc_value, di.fromsnap, strlen(di.fromsnap) + 1); 749 (void) strlcpy(zc.zc_name, di.tosnap, strlen(di.tosnap) + 1); 750 zc.zc_cookie = pipefd[1]; 751 752 iocerr = zfs_ioctl(zhp->zfs_hdl, ZFS_IOC_DIFF, &zc); 753 if (iocerr != 0) { 754 (void) snprintf(errbuf, sizeof (errbuf), 755 dgettext(TEXT_DOMAIN, "Unable to obtain diffs")); 756 if (errno == EPERM) { 757 zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN, 758 "\n The sys_mount privilege or diff delegated " 759 "permission is needed\n to execute the " 760 "diff ioctl")); 761 } else if (errno == EXDEV) { 762 zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN, 763 "\n Not an earlier snapshot from the same fs")); 764 } else if (errno != EPIPE || di.zerr == 0) { 765 zfs_error_aux(zhp->zfs_hdl, "%s", strerror(errno)); 766 } 767 (void) close(pipefd[1]); 768 (void) pthread_cancel(tid); 769 (void) pthread_join(tid, NULL); 770 teardown_differ_info(&di); 771 if (di.zerr != 0 && di.zerr != EPIPE) { 772 zfs_error_aux(zhp->zfs_hdl, "%s", strerror(di.zerr)); 773 return (zfs_error(zhp->zfs_hdl, EZFS_DIFF, di.errbuf)); 774 } else { 775 return (zfs_error(zhp->zfs_hdl, EZFS_DIFFDATA, errbuf)); 776 } 777 } 778 779 (void) close(pipefd[1]); 780 (void) pthread_join(tid, NULL); 781 782 if (di.zerr != 0) { 783 zfs_error_aux(zhp->zfs_hdl, "%s", strerror(di.zerr)); 784 return (zfs_error(zhp->zfs_hdl, EZFS_DIFF, di.errbuf)); 785 } 786 teardown_differ_info(&di); 787 return (0); 788 } 789