src/journal/sd-journal.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2011 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU Lesser General Public License as published by
  10   the Free Software Foundation; either version 2.1 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   Lesser General Public License for more details.
  17
  18   You should have received a copy of the GNU Lesser General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <errno.h>
  23 #include <fcntl.h>
  24 #include <stddef.h>
  25 #include <unistd.h>
  26 #include <sys/inotify.h>
  27 #include <sys/poll.h>
  28 #include <sys/vfs.h>
  29 #include <linux/magic.h>
  30
  31 #include "sd-journal.h"
  32 #include "journal-def.h"
  33 #include "journal-file.h"
  34 #include "hashmap.h"
  35 #include "list.h"
  36 #include "path-util.h"
  37 #include "lookup3.h"
  38 #include "compress.h"
  39 #include "journal-internal.h"
  40 #include "missing.h"
  41 #include "catalog.h"
  42 #include "replace-var.h"
  43
  44 #define JOURNAL_FILES_MAX 1024
  45
  46 #define JOURNAL_FILES_RECHECK_USEC (2 * USEC_PER_SEC)
  47
  48 #define REPLACE_VAR_MAX 256
  49
  50 #define DEFAULT_DATA_THRESHOLD (64*1024)
  51
  52 /* We return an error here only if we didn't manage to
  53    memorize the real error. */
  54 static int set_put_error(sd_journal *j, int r) {
  55         int k;
  56
  57         if (r >= 0)
  58                 return r;
  59
  60         k = set_ensure_allocated(&j->errors, trivial_hash_func, trivial_compare_func);
  61         if (k < 0)
  62                 return k;
  63
  64         return set_put(j->errors, INT_TO_PTR(r));
  65 }
  66
  67 static void detach_location(sd_journal *j) {
  68         Iterator i;
  69         JournalFile *f;
  70
  71         assert(j);
  72
  73         j->current_file = NULL;
  74         j->current_field = 0;
  75
  76         HASHMAP_FOREACH(f, j->files, i)
  77                 f->current_offset = 0;
  78 }
  79
  80 static void reset_location(sd_journal *j) {
  81         assert(j);
  82
  83         detach_location(j);
  84         zero(j->current_location);
  85 }
  86
  87 static void init_location(Location *l, LocationType type, JournalFile *f, Object *o) {
  88         assert(l);
  89         assert(type == LOCATION_DISCRETE || type == LOCATION_SEEK);
  90         assert(f);
  91         assert(o->object.type == OBJECT_ENTRY);
  92
  93         l->type = type;
  94         l->seqnum = le64toh(o->entry.seqnum);
  95         l->seqnum_id = f->header->seqnum_id;
  96         l->realtime = le64toh(o->entry.realtime);
  97         l->monotonic = le64toh(o->entry.monotonic);
  98         l->boot_id = o->entry.boot_id;
  99         l->xor_hash = le64toh(o->entry.xor_hash);
 100
 101         l->seqnum_set = l->realtime_set = l->monotonic_set = l->xor_hash_set = true;
 102 }
 103
 104 static void set_location(sd_journal *j, LocationType type, JournalFile *f, Object *o, uint64_t offset) {
 105         assert(j);
 106         assert(type == LOCATION_DISCRETE || type == LOCATION_SEEK);
 107         assert(f);
 108         assert(o);
 109
 110         init_location(&j->current_location, type, f, o);
 111
 112         j->current_file = f;
 113         j->current_field = 0;
 114
 115         f->current_offset = offset;
 116 }
 117
 118 static int match_is_valid(const void *data, size_t size) {
 119         const char *b, *p;
 120
 121         assert(data);
 122
 123         if (size < 2)
 124                 return false;
 125
 126         if (startswith(data, "__"))
 127                 return false;
 128
 129         b = data;
 130         for (p = b; p < b + size; p++) {
 131
 132                 if (*p == '=')
 133                         return p > b;
 134
 135                 if (*p == '_')
 136                         continue;
 137
 138                 if (*p >= 'A' && *p <= 'Z')
 139                         continue;
 140
 141                 if (*p >= '0' && *p <= '9')
 142                         continue;
 143
 144                 return false;
 145         }
 146
 147         return false;
 148 }
 149
 150 static bool same_field(const void *_a, size_t s, const void *_b, size_t t) {
 151         const uint8_t *a = _a, *b = _b;
 152         size_t j;
 153
 154         for (j = 0; j < s && j < t; j++) {
 155
 156                 if (a[j] != b[j])
 157                         return false;
 158
 159                 if (a[j] == '=')
 160                         return true;
 161         }
 162
 163         return true;
 164 }
 165
 166 static Match *match_new(Match *p, MatchType t) {
 167         Match *m;
 168
 169         m = new0(Match, 1);
 170         if (!m)
 171                 return NULL;
 172
 173         m->type = t;
 174
 175         if (p) {
 176                 m->parent = p;
 177                 LIST_PREPEND(Match, matches, p->matches, m);
 178         }
 179
 180         return m;
 181 }
 182
 183 static void match_free(Match *m) {
 184         assert(m);
 185
 186         while (m->matches)
 187                 match_free(m->matches);
 188
 189         if (m->parent)
 190                 LIST_REMOVE(Match, matches, m->parent->matches, m);
 191
 192         free(m->data);
 193         free(m);
 194 }
 195
 196 static void match_free_if_empty(Match *m) {
 197         assert(m);
 198
 199         if (m->matches)
 200                 return;
 201
 202         match_free(m);
 203 }
 204
 205 _public_ int sd_journal_add_match(sd_journal *j, const void *data, size_t size) {
 206         Match *l2, *l3, *add_here = NULL, *m;
 207         le64_t le_hash;
 208
 209         if (!j)
 210                 return -EINVAL;
 211
 212         if (!data)
 213                 return -EINVAL;
 214
 215         if (size == 0)
 216                 size = strlen(data);
 217
 218         if (!match_is_valid(data, size))
 219                 return -EINVAL;
 220
 221         /* level 0: OR term
 222          * level 1: AND terms
 223          * level 2: OR terms
 224          * level 3: concrete matches */
 225
 226         if (!j->level0) {
 227                 j->level0 = match_new(NULL, MATCH_OR_TERM);
 228                 if (!j->level0)
 229                         return -ENOMEM;
 230         }
 231
 232         if (!j->level1) {
 233                 j->level1 = match_new(j->level0, MATCH_AND_TERM);
 234                 if (!j->level1)
 235                         return -ENOMEM;
 236         }
 237
 238         assert(j->level0->type == MATCH_OR_TERM);
 239         assert(j->level1->type == MATCH_AND_TERM);
 240
 241         le_hash = htole64(hash64(data, size));
 242
 243         LIST_FOREACH(matches, l2, j->level1->matches) {
 244                 assert(l2->type == MATCH_OR_TERM);
 245
 246                 LIST_FOREACH(matches, l3, l2->matches) {
 247                         assert(l3->type == MATCH_DISCRETE);
 248
 249                         /* Exactly the same match already? Then ignore
 250                          * this addition */
 251                         if (l3->le_hash == le_hash &&
 252                             l3->size == size &&
 253                             memcmp(l3->data, data, size) == 0)
 254                                 return 0;
 255
 256                         /* Same field? Then let's add this to this OR term */
 257                         if (same_field(data, size, l3->data, l3->size)) {
 258                                 add_here = l2;
 259                                 break;
 260                         }
 261                 }
 262
 263                 if (add_here)
 264                         break;
 265         }
 266
 267         if (!add_here) {
 268                 add_here = match_new(j->level1, MATCH_OR_TERM);
 269                 if (!add_here)
 270                         goto fail;
 271         }
 272
 273         m = match_new(add_here, MATCH_DISCRETE);
 274         if (!m)
 275                 goto fail;
 276
 277         m->le_hash = le_hash;
 278         m->size = size;
 279         m->data = memdup(data, size);
 280         if (!m->data)
 281                 goto fail;
 282
 283         detach_location(j);
 284
 285         return 0;
 286
 287 fail:
 288         if (add_here)
 289                 match_free_if_empty(add_here);
 290
 291         if (j->level1)
 292                 match_free_if_empty(j->level1);
 293
 294         if (j->level0)
 295                 match_free_if_empty(j->level0);
 296
 297         return -ENOMEM;
 298 }
 299
 300 _public_ int sd_journal_add_disjunction(sd_journal *j) {
 301         Match *m;
 302
 303         assert(j);
 304
 305         if (!j->level0)
 306                 return 0;
 307
 308         if (!j->level1)
 309                 return 0;
 310
 311         if (!j->level1->matches)
 312                 return 0;
 313
 314         m = match_new(j->level0, MATCH_AND_TERM);
 315         if (!m)
 316                 return -ENOMEM;
 317
 318         j->level1 = m;
 319         return 0;
 320 }
 321
 322 static char *match_make_string(Match *m) {
 323         char *p, *r;
 324         Match *i;
 325         bool enclose = false;
 326
 327         if (!m)
 328                 return strdup("");
 329
 330         if (m->type == MATCH_DISCRETE)
 331                 return strndup(m->data, m->size);
 332
 333         p = NULL;
 334         LIST_FOREACH(matches, i, m->matches) {
 335                 char *t, *k;
 336
 337                 t = match_make_string(i);
 338                 if (!t) {
 339                         free(p);
 340                         return NULL;
 341                 }
 342
 343                 if (p) {
 344                         k = strjoin(p, m->type == MATCH_OR_TERM ? " OR " : " AND ", t, NULL);
 345                         free(p);
 346                         free(t);
 347
 348                         if (!k)
 349                                 return NULL;
 350
 351                         p = k;
 352
 353                         enclose = true;
 354                 } else {
 355                         free(p);
 356                         p = t;
 357                 }
 358         }
 359
 360         if (enclose) {
 361                 r = strjoin("(", p, ")", NULL);
 362                 free(p);
 363                 return r;
 364         }
 365
 366         return p;
 367 }
 368
 369 char *journal_make_match_string(sd_journal *j) {
 370         assert(j);
 371
 372         return match_make_string(j->level0);
 373 }
 374
 375 _public_ void sd_journal_flush_matches(sd_journal *j) {
 376
 377         if (!j)
 378                 return;
 379
 380         if (j->level0)
 381                 match_free(j->level0);
 382
 383         j->level0 = j->level1 = NULL;
 384
 385         detach_location(j);
 386 }
 387
 388 static int compare_entry_order(JournalFile *af, Object *_ao,
 389                          JournalFile *bf, uint64_t bp) {
 390
 391         uint64_t a, b;
 392         Object *ao, *bo;
 393         int r;
 394
 395         assert(af);
 396         assert(bf);
 397         assert(_ao);
 398
 399         /* The mmap cache might invalidate the object from the first
 400          * file if we look at the one from the second file. Hence
 401          * temporarily copy the header of the first one, and look at
 402          * that only. */
 403         ao = alloca(offsetof(EntryObject, items));
 404         memcpy(ao, _ao, offsetof(EntryObject, items));
 405
 406         r = journal_file_move_to_object(bf, OBJECT_ENTRY, bp, &bo);
 407         if (r < 0)
 408                 return strcmp(af->path, bf->path);
 409
 410         /* We operate on two different files here, hence we can access
 411          * two objects at the same time, which we normally can't.
 412          *
 413          * If contents and timestamps match, these entries are
 414          * identical, even if the seqnum does not match */
 415
 416         if (sd_id128_equal(ao->entry.boot_id, bo->entry.boot_id) &&
 417             ao->entry.monotonic == bo->entry.monotonic &&
 418             ao->entry.realtime == bo->entry.realtime &&
 419             ao->entry.xor_hash == bo->entry.xor_hash)
 420                 return 0;
 421
 422         if (sd_id128_equal(af->header->seqnum_id, bf->header->seqnum_id)) {
 423
 424                 /* If this is from the same seqnum source, compare
 425                  * seqnums */
 426                 a = le64toh(ao->entry.seqnum);
 427                 b = le64toh(bo->entry.seqnum);
 428
 429                 if (a < b)
 430                         return -1;
 431                 if (a > b)
 432                         return 1;
 433
 434                 /* Wow! This is weird, different data but the same
 435                  * seqnums? Something is borked, but let's make the
 436                  * best of it and compare by time. */
 437         }
 438
 439         if (sd_id128_equal(ao->entry.boot_id, bo->entry.boot_id)) {
 440
 441                 /* If the boot id matches compare monotonic time */
 442                 a = le64toh(ao->entry.monotonic);
 443                 b = le64toh(bo->entry.monotonic);
 444
 445                 if (a < b)
 446                         return -1;
 447                 if (a > b)
 448                         return 1;
 449         }
 450
 451         /* Otherwise compare UTC time */
 452         a = le64toh(ao->entry.realtime);
 453         b = le64toh(bo->entry.realtime);
 454
 455         if (a < b)
 456                 return -1;
 457         if (a > b)
 458                 return 1;
 459
 460         /* Finally, compare by contents */
 461         a = le64toh(ao->entry.xor_hash);
 462         b = le64toh(bo->entry.xor_hash);
 463
 464         if (a < b)
 465                 return -1;
 466         if (a > b)
 467                 return 1;
 468
 469         return 0;
 470 }
 471
 472 static int compare_with_location(JournalFile *af, Object *ao, Location *l) {
 473         uint64_t a;
 474
 475         assert(af);
 476         assert(ao);
 477         assert(l);
 478         assert(l->type == LOCATION_DISCRETE || l->type == LOCATION_SEEK);
 479
 480         if (l->monotonic_set &&
 481             sd_id128_equal(ao->entry.boot_id, l->boot_id) &&
 482             l->realtime_set &&
 483             le64toh(ao->entry.realtime) == l->realtime &&
 484             l->xor_hash_set &&
 485             le64toh(ao->entry.xor_hash) == l->xor_hash)
 486                 return 0;
 487
 488         if (l->seqnum_set &&
 489             sd_id128_equal(af->header->seqnum_id, l->seqnum_id)) {
 490
 491                 a = le64toh(ao->entry.seqnum);
 492
 493                 if (a < l->seqnum)
 494                         return -1;
 495                 if (a > l->seqnum)
 496                         return 1;
 497         }
 498
 499         if (l->monotonic_set &&
 500             sd_id128_equal(ao->entry.boot_id, l->boot_id)) {
 501
 502                 a = le64toh(ao->entry.monotonic);
 503
 504                 if (a < l->monotonic)
 505                         return -1;
 506                 if (a > l->monotonic)
 507                         return 1;
 508         }
 509
 510         if (l->realtime_set) {
 511
 512                 a = le64toh(ao->entry.realtime);
 513
 514                 if (a < l->realtime)
 515                         return -1;
 516                 if (a > l->realtime)
 517                         return 1;
 518         }
 519
 520         if (l->xor_hash_set) {
 521                 a = le64toh(ao->entry.xor_hash);
 522
 523                 if (a < l->xor_hash)
 524                         return -1;
 525                 if (a > l->xor_hash)
 526                         return 1;
 527         }
 528
 529         return 0;
 530 }
 531
 532 static int next_for_match(
 533                 sd_journal *j,
 534                 Match *m,
 535                 JournalFile *f,
 536                 uint64_t after_offset,
 537                 direction_t direction,
 538                 Object **ret,
 539                 uint64_t *offset) {
 540
 541         int r;
 542         uint64_t np = 0;
 543         Object *n;
 544
 545         assert(j);
 546         assert(m);
 547         assert(f);
 548
 549         if (m->type == MATCH_DISCRETE) {
 550                 uint64_t dp;
 551
 552                 r = journal_file_find_data_object_with_hash(f, m->data, m->size, le64toh(m->le_hash), NULL, &dp);
 553                 if (r <= 0)
 554                         return r;
 555
 556                 return journal_file_move_to_entry_by_offset_for_data(f, dp, after_offset, direction, ret, offset);
 557
 558         } else if (m->type == MATCH_OR_TERM) {
 559                 Match *i;
 560
 561                 /* Find the earliest match beyond after_offset */
 562
 563                 LIST_FOREACH(matches, i, m->matches) {
 564                         uint64_t cp;
 565
 566                         r = next_for_match(j, i, f, after_offset, direction, NULL, &cp);
 567                         if (r < 0)
 568                                 return r;
 569                         else if (r > 0) {
 570                                 if (np == 0 || (direction == DIRECTION_DOWN ? np > cp : np < cp))
 571                                         np = cp;
 572                         }
 573                 }
 574
 575         } else if (m->type == MATCH_AND_TERM) {
 576                 Match *i;
 577                 bool continue_looking;
 578
 579                 /* Always jump to the next matching entry and repeat
 580                  * this until we fine and offset that matches for all
 581                  * matches. */
 582
 583                 if (!m->matches)
 584                         return 0;
 585
 586                 np = 0;
 587                 do {
 588                         continue_looking = false;
 589
 590                         LIST_FOREACH(matches, i, m->matches) {
 591                                 uint64_t cp, limit;
 592
 593                                 if (np == 0)
 594                                         limit = after_offset;
 595                                 else if (direction == DIRECTION_DOWN)
 596                                         limit = MAX(np, after_offset);
 597                                 else
 598                                         limit = MIN(np, after_offset);
 599
 600                                 r = next_for_match(j, i, f, limit, direction, NULL, &cp);
 601                                 if (r <= 0)
 602                                         return r;
 603
 604                                 if ((direction == DIRECTION_DOWN ? cp >= after_offset : cp <= after_offset) &&
 605                                     (np == 0 || (direction == DIRECTION_DOWN ? cp > np : np < cp))) {
 606                                         np = cp;
 607                                         continue_looking = true;
 608                                 }
 609                         }
 610
 611                 } while (continue_looking);
 612         }
 613
 614         if (np == 0)
 615                 return 0;
 616
 617         r = journal_file_move_to_object(f, OBJECT_ENTRY, np, &n);
 618         if (r < 0)
 619                 return r;
 620
 621         if (ret)
 622                 *ret = n;
 623         if (offset)
 624                 *offset = np;
 625
 626         return 1;
 627 }
 628
 629 static int find_location_for_match(
 630                 sd_journal *j,
 631                 Match *m,
 632                 JournalFile *f,
 633                 direction_t direction,
 634                 Object **ret,
 635                 uint64_t *offset) {
 636
 637         int r;
 638
 639         assert(j);
 640         assert(m);
 641         assert(f);
 642
 643         if (m->type == MATCH_DISCRETE) {
 644                 uint64_t dp;
 645
 646                 r = journal_file_find_data_object_with_hash(f, m->data, m->size, le64toh(m->le_hash), NULL, &dp);
 647                 if (r <= 0)
 648                         return r;
 649
 650                 /* FIXME: missing: find by monotonic */
 651
 652                 if (j->current_location.type == LOCATION_HEAD)
 653                         return journal_file_next_entry_for_data(f, NULL, 0, dp, DIRECTION_DOWN, ret, offset);
 654                 if (j->current_location.type == LOCATION_TAIL)
 655                         return journal_file_next_entry_for_data(f, NULL, 0, dp, DIRECTION_UP, ret, offset);
 656                 if (j->current_location.seqnum_set && sd_id128_equal(j->current_location.seqnum_id, f->header->seqnum_id))
 657                         return journal_file_move_to_entry_by_seqnum_for_data(f, dp, j->current_location.seqnum, direction, ret, offset);
 658                 if (j->current_location.monotonic_set) {
 659                         r = journal_file_move_to_entry_by_monotonic_for_data(f, dp, j->current_location.boot_id, j->current_location.monotonic, direction, ret, offset);
 660                         if (r != -ENOENT)
 661                                 return r;
 662                 }
 663                 if (j->current_location.realtime_set)
 664                         return journal_file_move_to_entry_by_realtime_for_data(f, dp, j->current_location.realtime, direction, ret, offset);
 665
 666                 return journal_file_next_entry_for_data(f, NULL, 0, dp, direction, ret, offset);
 667
 668         } else if (m->type == MATCH_OR_TERM) {
 669                 uint64_t np = 0;
 670                 Object *n;
 671                 Match *i;
 672
 673                 /* Find the earliest match */
 674
 675                 LIST_FOREACH(matches, i, m->matches) {
 676                         uint64_t cp;
 677
 678                         r = find_location_for_match(j, i, f, direction, NULL, &cp);
 679                         if (r < 0)
 680                                 return r;
 681                         else if (r > 0) {
 682                                 if (np == 0 || (direction == DIRECTION_DOWN ? np > cp : np < cp))
 683                                         np = cp;
 684                         }
 685                 }
 686
 687                 if (np == 0)
 688                         return 0;
 689
 690                 r = journal_file_move_to_object(f, OBJECT_ENTRY, np, &n);
 691                 if (r < 0)
 692                         return r;
 693
 694                 if (ret)
 695                         *ret = n;
 696                 if (offset)
 697                         *offset = np;
 698
 699                 return 1;
 700
 701         } else {
 702                 Match *i;
 703                 uint64_t np = 0;
 704
 705                 assert(m->type == MATCH_AND_TERM);
 706
 707                 /* First jump to the last match, and then find the
 708                  * next one where all matches match */
 709
 710                 if (!m->matches)
 711                         return 0;
 712
 713                 LIST_FOREACH(matches, i, m->matches) {
 714                         uint64_t cp;
 715
 716                         r = find_location_for_match(j, i, f, direction, NULL, &cp);
 717                         if (r <= 0)
 718                                 return r;
 719
 720                         if (np == 0 || (direction == DIRECTION_DOWN ? np < cp : np > cp))
 721                                 np = cp;
 722                 }
 723
 724                 return next_for_match(j, m, f, np, direction, ret, offset);
 725         }
 726 }
 727
 728 static int find_location_with_matches(
 729                 sd_journal *j,
 730                 JournalFile *f,
 731                 direction_t direction,
 732                 Object **ret,
 733                 uint64_t *offset) {
 734
 735         int r;
 736
 737         assert(j);
 738         assert(f);
 739         assert(ret);
 740         assert(offset);
 741
 742         if (!j->level0) {
 743                 /* No matches is simple */
 744
 745                 if (j->current_location.type == LOCATION_HEAD)
 746                         return journal_file_next_entry(f, NULL, 0, DIRECTION_DOWN, ret, offset);
 747                 if (j->current_location.type == LOCATION_TAIL)
 748                         return journal_file_next_entry(f, NULL, 0, DIRECTION_UP, ret, offset);
 749                 if (j->current_location.seqnum_set && sd_id128_equal(j->current_location.seqnum_id, f->header->seqnum_id))
 750                         return journal_file_move_to_entry_by_seqnum(f, j->current_location.seqnum, direction, ret, offset);
 751                 if (j->current_location.monotonic_set) {
 752                         r = journal_file_move_to_entry_by_monotonic(f, j->current_location.boot_id, j->current_location.monotonic, direction, ret, offset);
 753                         if (r != -ENOENT)
 754                                 return r;
 755                 }
 756                 if (j->current_location.realtime_set)
 757                         return journal_file_move_to_entry_by_realtime(f, j->current_location.realtime, direction, ret, offset);
 758
 759                 return journal_file_next_entry(f, NULL, 0, direction, ret, offset);
 760         } else
 761                 return find_location_for_match(j, j->level0, f, direction, ret, offset);
 762 }
 763
 764 static int next_with_matches(
 765                 sd_journal *j,
 766                 JournalFile *f,
 767                 direction_t direction,
 768                 Object **ret,
 769                 uint64_t *offset) {
 770
 771         Object *c;
 772         uint64_t cp;
 773
 774         assert(j);
 775         assert(f);
 776         assert(ret);
 777         assert(offset);
 778
 779         c = *ret;
 780         cp = *offset;
 781
 782         /* No matches is easy. We simple advance the file
 783          * pointer by one. */
 784         if (!j->level0)
 785                 return journal_file_next_entry(f, c, cp, direction, ret, offset);
 786
 787         /* If we have a match then we look for the next matching entry
 788          * with an offset at least one step larger */
 789         return next_for_match(j, j->level0, f, direction == DIRECTION_DOWN ? cp+1 : cp-1, direction, ret, offset);
 790 }
 791
 792 static int next_beyond_location(sd_journal *j, JournalFile *f, direction_t direction, Object **ret, uint64_t *offset) {
 793         Object *c;
 794         uint64_t cp;
 795         int r;
 796
 797         assert(j);
 798         assert(f);
 799
 800         if (f->current_offset > 0) {
 801                 cp = f->current_offset;
 802
 803                 r = journal_file_move_to_object(f, OBJECT_ENTRY, cp, &c);
 804                 if (r < 0)
 805                         return r;
 806
 807                 r = next_with_matches(j, f, direction, &c, &cp);
 808                 if (r <= 0)
 809                         return r;
 810         } else {
 811                 r = find_location_with_matches(j, f, direction, &c, &cp);
 812                 if (r <= 0)
 813                         return r;
 814         }
 815
 816         /* OK, we found the spot, now let's advance until to an entry
 817          * that is actually different from what we were previously
 818          * looking at. This is necessary to handle entries which exist
 819          * in two (or more) journal files, and which shall all be
 820          * suppressed but one. */
 821
 822         for (;;) {
 823                 bool found;
 824
 825                 if (j->current_location.type == LOCATION_DISCRETE) {
 826                         int k;
 827
 828                         k = compare_with_location(f, c, &j->current_location);
 829                         if (direction == DIRECTION_DOWN)
 830                                 found = k > 0;
 831                         else
 832                                 found = k < 0;
 833                 } else
 834                         found = true;
 835
 836                 if (found) {
 837                         if (ret)
 838                                 *ret = c;
 839                         if (offset)
 840                                 *offset = cp;
 841                         return 1;
 842                 }
 843
 844                 r = next_with_matches(j, f, direction, &c, &cp);
 845                 if (r <= 0)
 846                         return r;
 847         }
 848 }
 849
 850 static int real_journal_next(sd_journal *j, direction_t direction) {
 851         JournalFile *f, *new_file = NULL;
 852         uint64_t new_offset = 0;
 853         Object *o;
 854         uint64_t p;
 855         Iterator i;
 856         int r;
 857
 858         if (!j)
 859                 return -EINVAL;
 860
 861         HASHMAP_FOREACH(f, j->files, i) {
 862                 bool found;
 863
 864                 r = next_beyond_location(j, f, direction, &o, &p);
 865                 if (r < 0) {
 866                         log_debug("Can't iterate through %s, ignoring: %s", f->path, strerror(-r));
 867                         continue;
 868                 } else if (r == 0)
 869                         continue;
 870
 871                 if (!new_file)
 872                         found = true;
 873                 else {
 874                         int k;
 875
 876                         k = compare_entry_order(f, o, new_file, new_offset);
 877
 878                         if (direction == DIRECTION_DOWN)
 879                                 found = k < 0;
 880                         else
 881                                 found = k > 0;
 882                 }
 883
 884                 if (found) {
 885                         new_file = f;
 886                         new_offset = p;
 887                 }
 888         }
 889
 890         if (!new_file)
 891                 return 0;
 892
 893         r = journal_file_move_to_object(new_file, OBJECT_ENTRY, new_offset, &o);
 894         if (r < 0)
 895                 return r;
 896
 897         set_location(j, LOCATION_DISCRETE, new_file, o, new_offset);
 898
 899         return 1;
 900 }
 901
 902 _public_ int sd_journal_next(sd_journal *j) {
 903         return real_journal_next(j, DIRECTION_DOWN);
 904 }
 905
 906 _public_ int sd_journal_previous(sd_journal *j) {
 907         return real_journal_next(j, DIRECTION_UP);
 908 }
 909
 910 static int real_journal_next_skip(sd_journal *j, direction_t direction, uint64_t skip) {
 911         int c = 0, r;
 912
 913         if (!j)
 914                 return -EINVAL;
 915
 916         if (skip == 0) {
 917                 /* If this is not a discrete skip, then at least
 918                  * resolve the current location */
 919                 if (j->current_location.type != LOCATION_DISCRETE)
 920                         return real_journal_next(j, direction);
 921
 922                 return 0;
 923         }
 924
 925         do {
 926                 r = real_journal_next(j, direction);
 927                 if (r < 0)
 928                         return r;
 929
 930                 if (r == 0)
 931                         return c;
 932
 933                 skip--;
 934                 c++;
 935         } while (skip > 0);
 936
 937         return c;
 938 }
 939
 940 _public_ int sd_journal_next_skip(sd_journal *j, uint64_t skip) {
 941         return real_journal_next_skip(j, DIRECTION_DOWN, skip);
 942 }
 943
 944 _public_ int sd_journal_previous_skip(sd_journal *j, uint64_t skip) {
 945         return real_journal_next_skip(j, DIRECTION_UP, skip);
 946 }
 947
 948 _public_ int sd_journal_get_cursor(sd_journal *j, char **cursor) {
 949         Object *o;
 950         int r;
 951         char bid[33], sid[33];
 952
 953         if (!j)
 954                 return -EINVAL;
 955         if (!cursor)
 956                 return -EINVAL;
 957
 958         if (!j->current_file || j->current_file->current_offset <= 0)
 959                 return -EADDRNOTAVAIL;
 960
 961         r = journal_file_move_to_object(j->current_file, OBJECT_ENTRY, j->current_file->current_offset, &o);
 962         if (r < 0)
 963                 return r;
 964
 965         sd_id128_to_string(j->current_file->header->seqnum_id, sid);
 966         sd_id128_to_string(o->entry.boot_id, bid);
 967
 968         if (asprintf(cursor,
 969                      "s=%s;i=%llx;b=%s;m=%llx;t=%llx;x=%llx",
 970                      sid, (unsigned long long) le64toh(o->entry.seqnum),
 971                      bid, (unsigned long long) le64toh(o->entry.monotonic),
 972                      (unsigned long long) le64toh(o->entry.realtime),
 973                      (unsigned long long) le64toh(o->entry.xor_hash)) < 0)
 974                 return -ENOMEM;
 975
 976         return 0;
 977 }
 978
 979 _public_ int sd_journal_seek_cursor(sd_journal *j, const char *cursor) {
 980         char *w, *state;
 981         size_t l;
 982         unsigned long long seqnum, monotonic, realtime, xor_hash;
 983         bool
 984                 seqnum_id_set = false,
 985                 seqnum_set = false,
 986                 boot_id_set = false,
 987                 monotonic_set = false,
 988                 realtime_set = false,
 989                 xor_hash_set = false;
 990         sd_id128_t seqnum_id, boot_id;
 991
 992         if (!j)
 993                 return -EINVAL;
 994         if (isempty(cursor))
 995                 return -EINVAL;
 996
 997         FOREACH_WORD_SEPARATOR(w, l, cursor, ";", state) {
 998                 char *item;
 999                 int k = 0;
1000
1001                 if (l < 2 || w[1] != '=')
1002                         return -EINVAL;
1003
1004                 item = strndup(w, l);
1005                 if (!item)
1006                         return -ENOMEM;
1007
1008                 switch (w[0]) {
1009
1010                 case 's':
1011                         seqnum_id_set = true;
1012                         k = sd_id128_from_string(item+2, &seqnum_id);
1013                         break;
1014
1015                 case 'i':
1016                         seqnum_set = true;
1017                         if (sscanf(item+2, "%llx", &seqnum) != 1)
1018                                 k = -EINVAL;
1019                         break;
1020
1021                 case 'b':
1022                         boot_id_set = true;
1023                         k = sd_id128_from_string(item+2, &boot_id);
1024                         break;
1025
1026                 case 'm':
1027                         monotonic_set = true;
1028                         if (sscanf(item+2, "%llx", &monotonic) != 1)
1029                                 k = -EINVAL;
1030                         break;
1031
1032                 case 't':
1033                         realtime_set = true;
1034                         if (sscanf(item+2, "%llx", &realtime) != 1)
1035                                 k = -EINVAL;
1036                         break;
1037
1038                 case 'x':
1039                         xor_hash_set = true;
1040                         if (sscanf(item+2, "%llx", &xor_hash) != 1)
1041                                 k = -EINVAL;
1042                         break;
1043                 }
1044
1045                 free(item);
1046
1047                 if (k < 0)
1048                         return k;
1049         }
1050
1051         if ((!seqnum_set || !seqnum_id_set) &&
1052             (!monotonic_set || !boot_id_set) &&
1053             !realtime_set)
1054                 return -EINVAL;
1055
1056         reset_location(j);
1057
1058         j->current_location.type = LOCATION_SEEK;
1059
1060         if (realtime_set) {
1061                 j->current_location.realtime = (uint64_t) realtime;
1062                 j->current_location.realtime_set = true;
1063         }
1064
1065         if (seqnum_set && seqnum_id_set) {
1066                 j->current_location.seqnum = (uint64_t) seqnum;
1067                 j->current_location.seqnum_id = seqnum_id;
1068                 j->current_location.seqnum_set = true;
1069         }
1070
1071         if (monotonic_set && boot_id_set) {
1072                 j->current_location.monotonic = (uint64_t) monotonic;
1073                 j->current_location.boot_id = boot_id;
1074                 j->current_location.monotonic_set = true;
1075         }
1076
1077         if (xor_hash_set) {
1078                 j->current_location.xor_hash = (uint64_t) xor_hash;
1079                 j->current_location.xor_hash_set = true;
1080         }
1081
1082         return 0;
1083 }
1084
1085 _public_ int sd_journal_test_cursor(sd_journal *j, const char *cursor) {
1086         int r;
1087         char *w, *state;
1088         size_t l;
1089         Object *o;
1090
1091         if (!j)
1092                 return -EINVAL;
1093         if (isempty(cursor))
1094                 return -EINVAL;
1095
1096         if (!j->current_file || j->current_file->current_offset <= 0)
1097                 return -EADDRNOTAVAIL;
1098
1099         r = journal_file_move_to_object(j->current_file, OBJECT_ENTRY, j->current_file->current_offset, &o);
1100         if (r < 0)
1101                 return r;
1102
1103         FOREACH_WORD_SEPARATOR(w, l, cursor, ";", state) {
1104                 _cleanup_free_ char *item = NULL;
1105                 sd_id128_t id;
1106                 unsigned long long ll;
1107                 int k = 0;
1108
1109                 if (l < 2 || w[1] != '=')
1110                         return -EINVAL;
1111
1112                 item = strndup(w, l);
1113                 if (!item)
1114                         return -ENOMEM;
1115
1116                 switch (w[0]) {
1117
1118                 case 's':
1119                         k = sd_id128_from_string(item+2, &id);
1120                         if (k < 0)
1121                                 return k;
1122                         if (!sd_id128_equal(id, j->current_file->header->seqnum_id))
1123                                 return 0;
1124                         break;
1125
1126                 case 'i':
1127                         if (sscanf(item+2, "%llx", &ll) != 1)
1128                                 return -EINVAL;
1129                         if (ll != le64toh(o->entry.seqnum))
1130                                 return 0;
1131                         break;
1132
1133                 case 'b':
1134                         k = sd_id128_from_string(item+2, &id);
1135                         if (k < 0)
1136                                 return k;
1137                         if (!sd_id128_equal(id, o->entry.boot_id))
1138                                 return 0;
1139                         break;
1140
1141                 case 'm':
1142                         if (sscanf(item+2, "%llx", &ll) != 1)
1143                                 return -EINVAL;
1144                         if (ll != le64toh(o->entry.monotonic))
1145                                 return 0;
1146                         break;
1147
1148                 case 't':
1149                         if (sscanf(item+2, "%llx", &ll) != 1)
1150                                 return -EINVAL;
1151                         if (ll != le64toh(o->entry.realtime))
1152                                 return 0;
1153                         break;
1154
1155                 case 'x':
1156                         if (sscanf(item+2, "%llx", &ll) != 1)
1157                                 return -EINVAL;
1158                         if (ll != le64toh(o->entry.xor_hash))
1159                                 return 0;
1160                         break;
1161                 }
1162         }
1163
1164         return 1;
1165 }
1166
1167
1168 _public_ int sd_journal_seek_monotonic_usec(sd_journal *j, sd_id128_t boot_id, uint64_t usec) {
1169         if (!j)
1170                 return -EINVAL;
1171
1172         reset_location(j);
1173         j->current_location.type = LOCATION_SEEK;
1174         j->current_location.boot_id = boot_id;
1175         j->current_location.monotonic = usec;
1176         j->current_location.monotonic_set = true;
1177
1178         return 0;
1179 }
1180
1181 _public_ int sd_journal_seek_realtime_usec(sd_journal *j, uint64_t usec) {
1182         if (!j)
1183                 return -EINVAL;
1184
1185         reset_location(j);
1186         j->current_location.type = LOCATION_SEEK;
1187         j->current_location.realtime = usec;
1188         j->current_location.realtime_set = true;
1189
1190         return 0;
1191 }
1192
1193 _public_ int sd_journal_seek_head(sd_journal *j) {
1194         if (!j)
1195                 return -EINVAL;
1196
1197         reset_location(j);
1198         j->current_location.type = LOCATION_HEAD;
1199
1200         return 0;
1201 }
1202
1203 _public_ int sd_journal_seek_tail(sd_journal *j) {
1204         if (!j)
1205                 return -EINVAL;
1206
1207         reset_location(j);
1208         j->current_location.type = LOCATION_TAIL;
1209
1210         return 0;
1211 }
1212
1213 static void check_network(sd_journal *j, int fd) {
1214         struct statfs sfs;
1215
1216         assert(j);
1217
1218         if (j->on_network)
1219                 return;
1220
1221         if (fstatfs(fd, &sfs) < 0)
1222                 return;
1223
1224         j->on_network =
1225                 (long)sfs.f_type == (long)CIFS_MAGIC_NUMBER ||
1226                 sfs.f_type == CODA_SUPER_MAGIC ||
1227                 sfs.f_type == NCP_SUPER_MAGIC ||
1228                 sfs.f_type == NFS_SUPER_MAGIC ||
1229                 sfs.f_type == SMB_SUPER_MAGIC;
1230 }
1231
1232 static int add_file(sd_journal *j, const char *prefix, const char *filename) {
1233         char _cleanup_free_ *path = NULL;
1234         int r;
1235         JournalFile *f;
1236
1237         assert(j);
1238         assert(prefix);
1239         assert(filename);
1240
1241         if ((j->flags & SD_JOURNAL_SYSTEM_ONLY) &&
1242             !(streq(filename, "system.journal") ||
1243               streq(filename, "system.journal~") ||
1244               (startswith(filename, "system@") &&
1245                (endswith(filename, ".journal") || endswith(filename, ".journal~")))))
1246                 return 0;
1247
1248         path = strjoin(prefix, "/", filename, NULL);
1249         if (!path)
1250                 return -ENOMEM;
1251
1252         if (hashmap_get(j->files, path))
1253                 return 0;
1254
1255         if (hashmap_size(j->files) >= JOURNAL_FILES_MAX) {
1256                 log_debug("Too many open journal files, not adding %s, ignoring.", path);
1257                 return set_put_error(j, -ETOOMANYREFS);
1258         }
1259
1260         r = journal_file_open(path, O_RDONLY, 0, false, false, NULL, j->mmap, NULL, &f);
1261         if (r < 0) {
1262                 if (errno == ENOENT)
1263                         return 0;
1264
1265                 return r;
1266         }
1267
1268         /* journal_file_dump(f); */
1269
1270         r = hashmap_put(j->files, f->path, f);
1271         if (r < 0) {
1272                 journal_file_close(f);
1273                 return r;
1274         }
1275
1276         log_debug("File %s got added.", f->path);
1277
1278         check_network(j, f->fd);
1279
1280         j->current_invalidate_counter ++;
1281
1282         return 0;
1283 }
1284
1285 static int remove_file(sd_journal *j, const char *prefix, const char *filename) {
1286         char *path;
1287         JournalFile *f;
1288
1289         assert(j);
1290         assert(prefix);
1291         assert(filename);
1292
1293         path = strjoin(prefix, "/", filename, NULL);
1294         if (!path)
1295                 return -ENOMEM;
1296
1297         f = hashmap_get(j->files, path);
1298         free(path);
1299         if (!f)
1300                 return 0;
1301
1302         hashmap_remove(j->files, f->path);
1303
1304         log_debug("File %s got removed.", f->path);
1305
1306         if (j->current_file == f) {
1307                 j->current_file = NULL;
1308                 j->current_field = 0;
1309         }
1310
1311         if (j->unique_file == f) {
1312                 j->unique_file = NULL;
1313                 j->unique_offset = 0;
1314         }
1315
1316         journal_file_close(f);
1317
1318         j->current_invalidate_counter ++;
1319
1320         return 0;
1321 }
1322
1323 static int add_directory(sd_journal *j, const char *prefix, const char *dirname) {
1324         char _cleanup_free_ *path = NULL;
1325         int r;
1326         DIR _cleanup_closedir_ *d = NULL;
1327         sd_id128_t id, mid;
1328         Directory *m;
1329
1330         assert(j);
1331         assert(prefix);
1332         assert(dirname);
1333
1334         log_debug("Considering %s/%s.", prefix, dirname);
1335
1336         if ((j->flags & SD_JOURNAL_LOCAL_ONLY) &&
1337             (sd_id128_from_string(dirname, &id) < 0 ||
1338              sd_id128_get_machine(&mid) < 0 ||
1339              !(sd_id128_equal(id, mid) || path_startswith(prefix, "/run"))))
1340             return 0;
1341
1342         path = strjoin(prefix, "/", dirname, NULL);
1343         if (!path)
1344                 return -ENOMEM;
1345
1346         d = opendir(path);
1347         if (!d) {
1348                 log_debug("Failed to open %s: %m", path);
1349                 if (errno == ENOENT)
1350                         return 0;
1351                 return -errno;
1352         }
1353
1354         m = hashmap_get(j->directories_by_path, path);
1355         if (!m) {
1356                 m = new0(Directory, 1);
1357                 if (!m)
1358                         return -ENOMEM;
1359
1360                 m->is_root = false;
1361                 m->path = path;
1362
1363                 if (hashmap_put(j->directories_by_path, m->path, m) < 0) {
1364                         free(m);
1365                         return -ENOMEM;
1366                 }
1367
1368                 path = NULL; /* avoid freeing in cleanup */
1369                 j->current_invalidate_counter ++;
1370
1371                 log_debug("Directory %s got added.", m->path);
1372
1373         } else if (m->is_root)
1374                 return 0;
1375
1376         if (m->wd <= 0 && j->inotify_fd >= 0) {
1377
1378                 m->wd = inotify_add_watch(j->inotify_fd, m->path,
1379                                           IN_CREATE|IN_MOVED_TO|IN_MODIFY|IN_ATTRIB|IN_DELETE|
1380                                           IN_DELETE_SELF|IN_MOVE_SELF|IN_UNMOUNT|IN_MOVED_FROM|
1381                                           IN_ONLYDIR);
1382
1383                 if (m->wd > 0 && hashmap_put(j->directories_by_wd, INT_TO_PTR(m->wd), m) < 0)
1384                         inotify_rm_watch(j->inotify_fd, m->wd);
1385         }
1386
1387         for (;;) {
1388                 struct dirent *de;
1389                 union dirent_storage buf;
1390
1391                 r = readdir_r(d, &buf.de, &de);
1392                 if (r != 0 || !de)
1393                         break;
1394
1395                 if (dirent_is_file_with_suffix(de, ".journal") ||
1396                     dirent_is_file_with_suffix(de, ".journal~")) {
1397                         r = add_file(j, m->path, de->d_name);
1398                         if (r < 0) {
1399                                 log_debug("Failed to add file %s/%s: %s",
1400                                           m->path, de->d_name, strerror(-r));
1401                                 r = set_put_error(j, r);
1402                                 if (r < 0)
1403                                         return r;
1404                         }
1405                 }
1406         }
1407
1408         check_network(j, dirfd(d));
1409
1410         return 0;
1411 }
1412
1413 static int add_root_directory(sd_journal *j, const char *p) {
1414         DIR _cleanup_closedir_ *d = NULL;
1415         Directory *m;
1416         int r;
1417
1418         assert(j);
1419         assert(p);
1420
1421         if ((j->flags & SD_JOURNAL_RUNTIME_ONLY) &&
1422             !path_startswith(p, "/run"))
1423                 return -EINVAL;
1424
1425         d = opendir(p);
1426         if (!d)
1427                 return -errno;
1428
1429         m = hashmap_get(j->directories_by_path, p);
1430         if (!m) {
1431                 m = new0(Directory, 1);
1432                 if (!m)
1433                         return -ENOMEM;
1434
1435                 m->is_root = true;
1436                 m->path = strdup(p);
1437                 if (!m->path) {
1438                         free(m);
1439                         return -ENOMEM;
1440                 }
1441
1442                 if (hashmap_put(j->directories_by_path, m->path, m) < 0) {
1443                         free(m->path);
1444                         free(m);
1445                         return -ENOMEM;
1446                 }
1447
1448                 j->current_invalidate_counter ++;
1449
1450                 log_debug("Root directory %s got added.", m->path);
1451
1452         } else if (!m->is_root)
1453                 return 0;
1454
1455         if (m->wd <= 0 && j->inotify_fd >= 0) {
1456
1457                 m->wd = inotify_add_watch(j->inotify_fd, m->path,
1458                                           IN_CREATE|IN_MOVED_TO|IN_MODIFY|IN_ATTRIB|IN_DELETE|
1459                                           IN_ONLYDIR);
1460
1461                 if (m->wd > 0 && hashmap_put(j->directories_by_wd, INT_TO_PTR(m->wd), m) < 0)
1462                         inotify_rm_watch(j->inotify_fd, m->wd);
1463         }
1464
1465         for (;;) {
1466                 struct dirent *de;
1467                 union dirent_storage buf;
1468                 sd_id128_t id;
1469
1470                 r = readdir_r(d, &buf.de, &de);
1471                 if (r != 0 || !de)
1472                         break;
1473
1474                 if (dirent_is_file_with_suffix(de, ".journal") ||
1475                     dirent_is_file_with_suffix(de, ".journal~")) {
1476                         r = add_file(j, m->path, de->d_name);
1477                         if (r < 0) {
1478                                 log_debug("Failed to add file %s/%s: %s",
1479                                           m->path, de->d_name, strerror(-r));
1480                                 r = set_put_error(j, r);
1481                                 if (r < 0)
1482                                         return r;
1483                         }
1484                 } else if ((de->d_type == DT_DIR || de->d_type == DT_LNK || de->d_type == DT_UNKNOWN) &&
1485                            sd_id128_from_string(de->d_name, &id) >= 0) {
1486
1487                         r = add_directory(j, m->path, de->d_name);
1488                         if (r < 0)
1489                                 log_debug("Failed to add directory %s/%s: %s", m->path, de->d_name, strerror(-r));
1490                 }
1491         }
1492
1493         check_network(j, dirfd(d));
1494
1495         return 0;
1496 }
1497
1498 static int remove_directory(sd_journal *j, Directory *d) {
1499         assert(j);
1500
1501         if (d->wd > 0) {
1502                 hashmap_remove(j->directories_by_wd, INT_TO_PTR(d->wd));
1503
1504                 if (j->inotify_fd >= 0)
1505                         inotify_rm_watch(j->inotify_fd, d->wd);
1506         }
1507
1508         hashmap_remove(j->directories_by_path, d->path);
1509
1510         if (d->is_root)
1511                 log_debug("Root directory %s got removed.", d->path);
1512         else
1513                 log_debug("Directory %s got removed.", d->path);
1514
1515         free(d->path);
1516         free(d);
1517
1518         return 0;
1519 }
1520
1521 static int add_search_paths(sd_journal *j) {
1522         int r;
1523         const char search_paths[] =
1524                 "/run/log/journal\0"
1525                 "/var/log/journal\0";
1526         const char *p;
1527
1528         assert(j);
1529
1530         /* We ignore most errors here, since the idea is to only open
1531          * what's actually accessible, and ignore the rest. */
1532
1533         NULSTR_FOREACH(p, search_paths) {
1534                 r = add_root_directory(j, p);
1535                 if (r < 0 && r != -ENOENT) {
1536                         r = set_put_error(j, r);
1537                         if (r < 0)
1538                                 return r;
1539                 }
1540         }
1541
1542         return 0;
1543 }
1544
1545 static int allocate_inotify(sd_journal *j) {
1546         assert(j);
1547
1548         if (j->inotify_fd < 0) {
1549                 j->inotify_fd = inotify_init1(IN_NONBLOCK|IN_CLOEXEC);
1550                 if (j->inotify_fd < 0)
1551                         return -errno;
1552         }
1553
1554         if (!j->directories_by_wd) {
1555                 j->directories_by_wd = hashmap_new(trivial_hash_func, trivial_compare_func);
1556                 if (!j->directories_by_wd)
1557                         return -ENOMEM;
1558         }
1559
1560         return 0;
1561 }
1562
1563 static sd_journal *journal_new(int flags, const char *path) {
1564         sd_journal *j;
1565
1566         j = new0(sd_journal, 1);
1567         if (!j)
1568                 return NULL;
1569
1570         j->inotify_fd = -1;
1571         j->flags = flags;
1572         j->data_threshold = DEFAULT_DATA_THRESHOLD;
1573
1574         if (path) {
1575                 j->path = strdup(path);
1576                 if (!j->path)
1577                         goto fail;
1578         }
1579
1580         j->files = hashmap_new(string_hash_func, string_compare_func);
1581         j->directories_by_path = hashmap_new(string_hash_func, string_compare_func);
1582         j->mmap = mmap_cache_new();
1583         if (!j->files || !j->directories_by_path || !j->mmap)
1584                 goto fail;
1585
1586         return j;
1587
1588 fail:
1589         sd_journal_close(j);
1590         return NULL;
1591 }
1592
1593 _public_ int sd_journal_open(sd_journal **ret, int flags) {
1594         sd_journal *j;
1595         int r;
1596
1597         if (!ret)
1598                 return -EINVAL;
1599
1600         if (flags & ~(SD_JOURNAL_LOCAL_ONLY|
1601                       SD_JOURNAL_RUNTIME_ONLY|
1602                       SD_JOURNAL_SYSTEM_ONLY))
1603                 return -EINVAL;
1604
1605         j = journal_new(flags, NULL);
1606         if (!j)
1607                 return -ENOMEM;
1608
1609         r = add_search_paths(j);
1610         if (r < 0)
1611                 goto fail;
1612
1613         *ret = j;
1614         return 0;
1615
1616 fail:
1617         sd_journal_close(j);
1618
1619         return r;
1620 }
1621
1622 _public_ int sd_journal_open_directory(sd_journal **ret, const char *path, int flags) {
1623         sd_journal *j;
1624         int r;
1625
1626         if (!ret)
1627                 return -EINVAL;
1628
1629         if (!path)
1630                 return -EINVAL;
1631
1632         if (flags != 0)
1633                 return -EINVAL;
1634
1635         j = journal_new(flags, path);
1636         if (!j)
1637                 return -ENOMEM;
1638
1639         r = add_root_directory(j, path);
1640         if (r < 0) {
1641                 set_put_error(j, r);
1642                 goto fail;
1643         }
1644
1645         *ret = j;
1646         return 0;
1647
1648 fail:
1649         sd_journal_close(j);
1650
1651         return r;
1652 }
1653
1654 _public_ void sd_journal_close(sd_journal *j) {
1655         Directory *d;
1656         JournalFile *f;
1657
1658         if (!j)
1659                 return;
1660
1661         sd_journal_flush_matches(j);
1662
1663         while ((f = hashmap_steal_first(j->files)))
1664                 journal_file_close(f);
1665
1666         hashmap_free(j->files);
1667
1668         while ((d = hashmap_first(j->directories_by_path)))
1669                 remove_directory(j, d);
1670
1671         while ((d = hashmap_first(j->directories_by_wd)))
1672                 remove_directory(j, d);
1673
1674         hashmap_free(j->directories_by_path);
1675         hashmap_free(j->directories_by_wd);
1676
1677         if (j->inotify_fd >= 0)
1678                 close_nointr_nofail(j->inotify_fd);
1679
1680         if (j->mmap)
1681                 mmap_cache_unref(j->mmap);
1682
1683         free(j->path);
1684         free(j->unique_field);
1685         set_free(j->errors);
1686         free(j);
1687 }
1688
1689 _public_ int sd_journal_get_realtime_usec(sd_journal *j, uint64_t *ret) {
1690         Object *o;
1691         JournalFile *f;
1692         int r;
1693
1694         if (!j)
1695                 return -EINVAL;
1696         if (!ret)
1697                 return -EINVAL;
1698
1699         f = j->current_file;
1700         if (!f)
1701                 return -EADDRNOTAVAIL;
1702
1703         if (f->current_offset <= 0)
1704                 return -EADDRNOTAVAIL;
1705
1706         r = journal_file_move_to_object(f, OBJECT_ENTRY, f->current_offset, &o);
1707         if (r < 0)
1708                 return r;
1709
1710         *ret = le64toh(o->entry.realtime);
1711         return 0;
1712 }
1713
1714 _public_ int sd_journal_get_monotonic_usec(sd_journal *j, uint64_t *ret, sd_id128_t *ret_boot_id) {
1715         Object *o;
1716         JournalFile *f;
1717         int r;
1718         sd_id128_t id;
1719
1720         if (!j)
1721                 return -EINVAL;
1722
1723         f = j->current_file;
1724         if (!f)
1725                 return -EADDRNOTAVAIL;
1726
1727         if (f->current_offset <= 0)
1728                 return -EADDRNOTAVAIL;
1729
1730         r = journal_file_move_to_object(f, OBJECT_ENTRY, f->current_offset, &o);
1731         if (r < 0)
1732                 return r;
1733
1734         if (ret_boot_id)
1735                 *ret_boot_id = o->entry.boot_id;
1736         else {
1737                 r = sd_id128_get_boot(&id);
1738                 if (r < 0)
1739                         return r;
1740
1741                 if (!sd_id128_equal(id, o->entry.boot_id))
1742                         return -ESTALE;
1743         }
1744
1745         if (ret)
1746                 *ret = le64toh(o->entry.monotonic);
1747
1748         return 0;
1749 }
1750
1751 static bool field_is_valid(const char *field) {
1752         const char *p;
1753
1754         assert(field);
1755
1756         if (isempty(field))
1757                 return false;
1758
1759         if (startswith(field, "__"))
1760                 return false;
1761
1762         for (p = field; *p; p++) {
1763
1764                 if (*p == '_')
1765                         continue;
1766
1767                 if (*p >= 'A' && *p <= 'Z')
1768                         continue;
1769
1770                 if (*p >= '0' && *p <= '9')
1771                         continue;
1772
1773                 return false;
1774         }
1775
1776         return true;
1777 }
1778
1779 _public_ int sd_journal_get_data(sd_journal *j, const char *field, const void **data, size_t *size) {
1780         JournalFile *f;
1781         uint64_t i, n;
1782         size_t field_length;
1783         int r;
1784         Object *o;
1785
1786         if (!j)
1787                 return -EINVAL;
1788         if (!field)
1789                 return -EINVAL;
1790         if (!data)
1791                 return -EINVAL;
1792         if (!size)
1793                 return -EINVAL;
1794
1795         if (!field_is_valid(field))
1796                 return -EINVAL;
1797
1798         f = j->current_file;
1799         if (!f)
1800                 return -EADDRNOTAVAIL;
1801
1802         if (f->current_offset <= 0)
1803                 return -EADDRNOTAVAIL;
1804
1805         r = journal_file_move_to_object(f, OBJECT_ENTRY, f->current_offset, &o);
1806         if (r < 0)
1807                 return r;
1808
1809         field_length = strlen(field);
1810
1811         n = journal_file_entry_n_items(o);
1812         for (i = 0; i < n; i++) {
1813                 uint64_t p, l;
1814                 le64_t le_hash;
1815                 size_t t;
1816
1817                 p = le64toh(o->entry.items[i].object_offset);
1818                 le_hash = o->entry.items[i].hash;
1819                 r = journal_file_move_to_object(f, OBJECT_DATA, p, &o);
1820                 if (r < 0)
1821                         return r;
1822
1823                 if (le_hash != o->data.hash)
1824                         return -EBADMSG;
1825
1826                 l = le64toh(o->object.size) - offsetof(Object, data.payload);
1827
1828                 if (o->object.flags & OBJECT_COMPRESSED) {
1829
1830 #ifdef HAVE_XZ
1831                         if (uncompress_startswith(o->data.payload, l,
1832                                                   &f->compress_buffer, &f->compress_buffer_size,
1833                                                   field, field_length, '=')) {
1834
1835                                 uint64_t rsize;
1836
1837                                 if (!uncompress_blob(o->data.payload, l,
1838                                                      &f->compress_buffer, &f->compress_buffer_size, &rsize,
1839                                                      j->data_threshold))
1840                                         return -EBADMSG;
1841
1842                                 *data = f->compress_buffer;
1843                                 *size = (size_t) rsize;
1844
1845                                 return 0;
1846                         }
1847 #else
1848                         return -EPROTONOSUPPORT;
1849 #endif
1850
1851                 } else if (l >= field_length+1 &&
1852                            memcmp(o->data.payload, field, field_length) == 0 &&
1853                            o->data.payload[field_length] == '=') {
1854
1855                         t = (size_t) l;
1856
1857                         if ((uint64_t) t != l)
1858                                 return -E2BIG;
1859
1860                         *data = o->data.payload;
1861                         *size = t;
1862
1863                         return 0;
1864                 }
1865
1866                 r = journal_file_move_to_object(f, OBJECT_ENTRY, f->current_offset, &o);
1867                 if (r < 0)
1868                         return r;
1869         }
1870
1871         return -ENOENT;
1872 }
1873
1874 static int return_data(sd_journal *j, JournalFile *f, Object *o, const void **data, size_t *size) {
1875         size_t t;
1876         uint64_t l;
1877
1878         l = le64toh(o->object.size) - offsetof(Object, data.payload);
1879         t = (size_t) l;
1880
1881         /* We can't read objects larger than 4G on a 32bit machine */
1882         if ((uint64_t) t != l)
1883                 return -E2BIG;
1884
1885         if (o->object.flags & OBJECT_COMPRESSED) {
1886 #ifdef HAVE_XZ
1887                 uint64_t rsize;
1888
1889                 if (!uncompress_blob(o->data.payload, l, &f->compress_buffer, &f->compress_buffer_size, &rsize, j->data_threshold))
1890                         return -EBADMSG;
1891
1892                 *data = f->compress_buffer;
1893                 *size = (size_t) rsize;
1894 #else
1895                 return -EPROTONOSUPPORT;
1896 #endif
1897         } else {
1898                 *data = o->data.payload;
1899                 *size = t;
1900         }
1901
1902         return 0;
1903 }
1904
1905 _public_ int sd_journal_enumerate_data(sd_journal *j, const void **data, size_t *size) {
1906         JournalFile *f;
1907         uint64_t p, n;
1908         le64_t le_hash;
1909         int r;
1910         Object *o;
1911
1912         if (!j)
1913                 return -EINVAL;
1914         if (!data)
1915                 return -EINVAL;
1916         if (!size)
1917                 return -EINVAL;
1918
1919         f = j->current_file;
1920         if (!f)
1921                 return -EADDRNOTAVAIL;
1922
1923         if (f->current_offset <= 0)
1924                 return -EADDRNOTAVAIL;
1925
1926         r = journal_file_move_to_object(f, OBJECT_ENTRY, f->current_offset, &o);
1927         if (r < 0)
1928                 return r;
1929
1930         n = journal_file_entry_n_items(o);
1931         if (j->current_field >= n)
1932                 return 0;
1933
1934         p = le64toh(o->entry.items[j->current_field].object_offset);
1935         le_hash = o->entry.items[j->current_field].hash;
1936         r = journal_file_move_to_object(f, OBJECT_DATA, p, &o);
1937         if (r < 0)
1938                 return r;
1939
1940         if (le_hash != o->data.hash)
1941                 return -EBADMSG;
1942
1943         r = return_data(j, f, o, data, size);
1944         if (r < 0)
1945                 return r;
1946
1947         j->current_field ++;
1948
1949         return 1;
1950 }
1951
1952 _public_ void sd_journal_restart_data(sd_journal *j) {
1953         if (!j)
1954                 return;
1955
1956         j->current_field = 0;
1957 }
1958
1959 _public_ int sd_journal_get_fd(sd_journal *j) {
1960         int r;
1961
1962         if (!j)
1963                 return -EINVAL;
1964
1965         if (j->inotify_fd >= 0)
1966                 return j->inotify_fd;
1967
1968         r = allocate_inotify(j);
1969         if (r < 0)
1970                 return r;
1971
1972         /* Iterate through all dirs again, to add them to the
1973          * inotify */
1974         if (j->path)
1975                 r = add_root_directory(j, j->path);
1976         else
1977                 r = add_search_paths(j);
1978         if (r < 0)
1979                 return r;
1980
1981         return j->inotify_fd;
1982 }
1983
1984 _public_ int sd_journal_get_events(sd_journal *j) {
1985         int fd;
1986
1987         if (!j)
1988                 return -EINVAL;
1989
1990         fd = sd_journal_get_fd(j);
1991         if (fd < 0)
1992                 return fd;
1993
1994         return POLLIN;
1995 }
1996
1997 static void process_inotify_event(sd_journal *j, struct inotify_event *e) {
1998         Directory *d;
1999         int r;
2000
2001         assert(j);
2002         assert(e);
2003
2004         /* Is this a subdirectory we watch? */
2005         d = hashmap_get(j->directories_by_wd, INT_TO_PTR(e->wd));
2006         if (d) {
2007                 sd_id128_t id;
2008
2009                 if (!(e->mask & IN_ISDIR) && e->len > 0 &&
2010                     (endswith(e->name, ".journal") ||
2011                      endswith(e->name, ".journal~"))) {
2012
2013                         /* Event for a journal file */
2014
2015                         if (e->mask & (IN_CREATE|IN_MOVED_TO|IN_MODIFY|IN_ATTRIB)) {
2016                                 r = add_file(j, d->path, e->name);
2017                                 if (r < 0) {
2018                                         log_debug("Failed to add file %s/%s: %s",
2019                                                   d->path, e->name, strerror(-r));
2020                                         set_put_error(j, r);
2021                                 }
2022
2023                         } else if (e->mask & (IN_DELETE|IN_MOVED_FROM|IN_UNMOUNT)) {
2024
2025                                 r = remove_file(j, d->path, e->name);
2026                                 if (r < 0)
2027                                         log_debug("Failed to remove file %s/%s: %s", d->path, e->name, strerror(-r));
2028                         }
2029
2030                 } else if (!d->is_root && e->len == 0) {
2031
2032                         /* Event for a subdirectory */
2033
2034                         if (e->mask & (IN_DELETE_SELF|IN_MOVE_SELF|IN_UNMOUNT)) {
2035                                 r = remove_directory(j, d);
2036                                 if (r < 0)
2037                                         log_debug("Failed to remove directory %s: %s", d->path, strerror(-r));
2038                         }
2039
2040
2041                 } else if (d->is_root && (e->mask & IN_ISDIR) && e->len > 0 && sd_id128_from_string(e->name, &id) >= 0) {
2042
2043                         /* Event for root directory */
2044
2045                         if (e->mask & (IN_CREATE|IN_MOVED_TO|IN_MODIFY|IN_ATTRIB)) {
2046                                 r = add_directory(j, d->path, e->name);
2047                                 if (r < 0)
2048                                         log_debug("Failed to add directory %s/%s: %s", d->path, e->name, strerror(-r));
2049                         }
2050                 }
2051
2052                 return;
2053         }
2054
2055         if (e->mask & IN_IGNORED)
2056                 return;
2057
2058         log_warning("Unknown inotify event.");
2059 }
2060
2061 static int determine_change(sd_journal *j) {
2062         bool b;
2063
2064         assert(j);
2065
2066         b = j->current_invalidate_counter != j->last_invalidate_counter;
2067         j->last_invalidate_counter = j->current_invalidate_counter;
2068
2069         return b ? SD_JOURNAL_INVALIDATE : SD_JOURNAL_APPEND;
2070 }
2071
2072 _public_ int sd_journal_process(sd_journal *j) {
2073         uint8_t buffer[sizeof(struct inotify_event) + FILENAME_MAX] _alignas_(struct inotify_event);
2074         bool got_something = false;
2075
2076         if (!j)
2077                 return -EINVAL;
2078
2079         for (;;) {
2080                 struct inotify_event *e;
2081                 ssize_t l;
2082
2083                 l = read(j->inotify_fd, buffer, sizeof(buffer));
2084                 if (l < 0) {
2085                         if (errno == EAGAIN || errno == EINTR)
2086                                 return got_something ? determine_change(j) : SD_JOURNAL_NOP;
2087
2088                         return -errno;
2089                 }
2090
2091                 got_something = true;
2092
2093                 e = (struct inotify_event*) buffer;
2094                 while (l > 0) {
2095                         size_t step;
2096
2097                         process_inotify_event(j, e);
2098
2099                         step = sizeof(struct inotify_event) + e->len;
2100                         assert(step <= (size_t) l);
2101
2102                         e = (struct inotify_event*) ((uint8_t*) e + step);
2103                         l -= step;
2104                 }
2105         }
2106
2107         return determine_change(j);
2108 }
2109
2110 _public_ int sd_journal_wait(sd_journal *j, uint64_t timeout_usec) {
2111         int r;
2112
2113         assert(j);
2114
2115         if (j->inotify_fd < 0) {
2116
2117                 /* This is the first invocation, hence create the
2118                  * inotify watch */
2119                 r = sd_journal_get_fd(j);
2120                 if (r < 0)
2121                         return r;
2122
2123                 /* The journal might have changed since the context
2124                  * object was created and we weren't watching before,
2125                  * hence don't wait for anything, and return
2126                  * immediately. */
2127                 return determine_change(j);
2128         }
2129
2130         if (j->on_network) {
2131                 /* If we are on the network we need to regularly check
2132                  * for changes manually */
2133
2134                 if (timeout_usec == (uint64_t) -1 || timeout_usec > JOURNAL_FILES_RECHECK_USEC)
2135                         timeout_usec = JOURNAL_FILES_RECHECK_USEC;
2136         }
2137
2138         do {
2139                 r = fd_wait_for_event(j->inotify_fd, POLLIN, timeout_usec);
2140         } while (r == -EINTR);
2141
2142         if (r < 0)
2143                 return r;
2144
2145         return sd_journal_process(j);
2146 }
2147
2148 _public_ int sd_journal_get_cutoff_realtime_usec(sd_journal *j, uint64_t *from, uint64_t *to) {
2149         Iterator i;
2150         JournalFile *f;
2151         bool first = true;
2152         int r;
2153
2154         if (!j)
2155                 return -EINVAL;
2156         if (!from && !to)
2157                 return -EINVAL;
2158
2159         HASHMAP_FOREACH(f, j->files, i) {
2160                 usec_t fr, t;
2161
2162                 r = journal_file_get_cutoff_realtime_usec(f, &fr, &t);
2163                 if (r == -ENOENT)
2164                         continue;
2165                 if (r < 0)
2166                         return r;
2167                 if (r == 0)
2168                         continue;
2169
2170                 if (first) {
2171                         if (from)
2172                                 *from = fr;
2173                         if (to)
2174                                 *to = t;
2175                         first = false;
2176                 } else {
2177                         if (from)
2178                                 *from = MIN(fr, *from);
2179                         if (to)
2180                                 *to = MAX(t, *to);
2181                 }
2182         }
2183
2184         return first ? 0 : 1;
2185 }
2186
2187 _public_ int sd_journal_get_cutoff_monotonic_usec(sd_journal *j, sd_id128_t boot_id, uint64_t *from, uint64_t *to) {
2188         Iterator i;
2189         JournalFile *f;
2190         bool first = true;
2191         int r;
2192
2193         if (!j)
2194                 return -EINVAL;
2195         if (!from && !to)
2196                 return -EINVAL;
2197
2198         HASHMAP_FOREACH(f, j->files, i) {
2199                 usec_t fr, t;
2200
2201                 r = journal_file_get_cutoff_monotonic_usec(f, boot_id, &fr, &t);
2202                 if (r == -ENOENT)
2203                         continue;
2204                 if (r < 0)
2205                         return r;
2206                 if (r == 0)
2207                         continue;
2208
2209                 if (first) {
2210                         if (from)
2211                                 *from = fr;
2212                         if (to)
2213                                 *to = t;
2214                         first = false;
2215                 } else {
2216                         if (from)
2217                                 *from = MIN(fr, *from);
2218                         if (to)
2219                                 *to = MAX(t, *to);
2220                 }
2221         }
2222
2223         return first ? 0 : 1;
2224 }
2225
2226 void journal_print_header(sd_journal *j) {
2227         Iterator i;
2228         JournalFile *f;
2229         bool newline = false;
2230
2231         assert(j);
2232
2233         HASHMAP_FOREACH(f, j->files, i) {
2234                 if (newline)
2235                         putchar('\n');
2236                 else
2237                         newline = true;
2238
2239                 journal_file_print_header(f);
2240         }
2241 }
2242
2243 _public_ int sd_journal_get_usage(sd_journal *j, uint64_t *bytes) {
2244         Iterator i;
2245         JournalFile *f;
2246         uint64_t sum = 0;
2247
2248         if (!j)
2249                 return -EINVAL;
2250         if (!bytes)
2251                 return -EINVAL;
2252
2253         HASHMAP_FOREACH(f, j->files, i) {
2254                 struct stat st;
2255
2256                 if (fstat(f->fd, &st) < 0)
2257                         return -errno;
2258
2259                 sum += (uint64_t) st.st_blocks * 512ULL;
2260         }
2261
2262         *bytes = sum;
2263         return 0;
2264 }
2265
2266 _public_ int sd_journal_query_unique(sd_journal *j, const char *field) {
2267         char *f;
2268
2269         if (!j)
2270                 return -EINVAL;
2271         if (isempty(field))
2272                 return -EINVAL;
2273         if (!field_is_valid(field))
2274                 return -EINVAL;
2275
2276         f = strdup(field);
2277         if (!f)
2278                 return -ENOMEM;
2279
2280         free(j->unique_field);
2281         j->unique_field = f;
2282         j->unique_file = NULL;
2283         j->unique_offset = 0;
2284
2285         return 0;
2286 }
2287
2288 _public_ int sd_journal_enumerate_unique(sd_journal *j, const void **data, size_t *l) {
2289         Object *o;
2290         size_t k;
2291         int r;
2292
2293         if (!j)
2294                 return -EINVAL;
2295         if (!data)
2296                 return -EINVAL;
2297         if (!l)
2298                 return -EINVAL;
2299         if (!j->unique_field)
2300                 return -EINVAL;
2301
2302         k = strlen(j->unique_field);
2303
2304         if (!j->unique_file) {
2305                 j->unique_file = hashmap_first(j->files);
2306                 if (!j->unique_file)
2307                         return 0;
2308                 j->unique_offset = 0;
2309         }
2310
2311         for (;;) {
2312                 JournalFile *of;
2313                 Iterator i;
2314                 const void *odata;
2315                 size_t ol;
2316                 bool found;
2317
2318                 /* Proceed to next data object in the field's linked list */
2319                 if (j->unique_offset == 0) {
2320                         r = journal_file_find_field_object(j->unique_file, j->unique_field, k, &o, NULL);
2321                         if (r < 0)
2322                                 return r;
2323
2324                         j->unique_offset = r > 0 ? le64toh(o->field.head_data_offset) : 0;
2325                 } else {
2326                         r = journal_file_move_to_object(j->unique_file, OBJECT_DATA, j->unique_offset, &o);
2327                         if (r < 0)
2328                                 return r;
2329
2330                         j->unique_offset = le64toh(o->data.next_field_offset);
2331                 }
2332
2333                 /* We reached the end of the list? Then start again, with the next file */
2334                 if (j->unique_offset == 0) {
2335                         JournalFile *n;
2336
2337                         n = hashmap_next(j->files, j->unique_file->path);
2338                         if (!n)
2339                                 return 0;
2340
2341                         j->unique_file = n;
2342                         continue;
2343                 }
2344
2345                 /* We do not use the type context here, but 0 instead,
2346                  * so that we can look at this data object at the same
2347                  * time as one on another file */
2348                 r = journal_file_move_to_object(j->unique_file, 0, j->unique_offset, &o);
2349                 if (r < 0)
2350                         return r;
2351
2352                 /* Let's do the type check by hand, since we used 0 context above. */
2353                 if (o->object.type != OBJECT_DATA)
2354                         return -EBADMSG;
2355
2356                 r = return_data(j, j->unique_file, o, &odata, &ol);
2357                 if (r < 0)
2358                         return r;
2359
2360                 /* OK, now let's see if we already returned this data
2361                  * object by checking if it exists in the earlier
2362                  * traversed files. */
2363                 found = false;
2364                 HASHMAP_FOREACH(of, j->files, i) {
2365                         Object *oo;
2366                         uint64_t op;
2367
2368                         if (of == j->unique_file)
2369                                 break;
2370
2371                         /* Skip this file it didn't have any fields
2372                          * indexed */
2373                         if (JOURNAL_HEADER_CONTAINS(of->header, n_fields) &&
2374                             le64toh(of->header->n_fields) <= 0)
2375                                 continue;
2376
2377                         r = journal_file_find_data_object_with_hash(of, odata, ol, le64toh(o->data.hash), &oo, &op);
2378                         if (r < 0)
2379                                 return r;
2380
2381                         if (r > 0)
2382                                 found = true;
2383                 }
2384
2385                 if (found)
2386                         continue;
2387
2388                 r = return_data(j, j->unique_file, o, data, l);
2389                 if (r < 0)
2390                         return r;
2391
2392                 return 1;
2393         }
2394 }
2395
2396 _public_ void sd_journal_restart_unique(sd_journal *j) {
2397         if (!j)
2398                 return;
2399
2400         j->unique_file = NULL;
2401         j->unique_offset = 0;
2402 }
2403
2404 _public_ int sd_journal_reliable_fd(sd_journal *j) {
2405         if (!j)
2406                 return -EINVAL;
2407
2408         return !j->on_network;
2409 }
2410
2411 static char *lookup_field(const char *field, void *userdata) {
2412         sd_journal *j = userdata;
2413         const void *data;
2414         size_t size, d;
2415         int r;
2416
2417         assert(field);
2418         assert(j);
2419
2420         r = sd_journal_get_data(j, field, &data, &size);
2421         if (r < 0 ||
2422             size > REPLACE_VAR_MAX)
2423                 return strdup(field);
2424
2425         d = strlen(field) + 1;
2426
2427         return strndup((const char*) data + d, size - d);
2428 }
2429
2430 _public_ int sd_journal_get_catalog(sd_journal *j, char **ret) {
2431         const void *data;
2432         size_t size;
2433         sd_id128_t id;
2434         _cleanup_free_ char *text = NULL, *cid = NULL;
2435         char *t;
2436         int r;
2437
2438         if (!j)
2439                 return -EINVAL;
2440         if (!ret)
2441                 return -EINVAL;
2442
2443         r = sd_journal_get_data(j, "MESSAGE_ID", &data, &size);
2444         if (r < 0)
2445                 return r;
2446
2447         cid = strndup((const char*) data + 11, size - 11);
2448         if (!cid)
2449                 return -ENOMEM;
2450
2451         r = sd_id128_from_string(cid, &id);
2452         if (r < 0)
2453                 return r;
2454
2455         r = catalog_get(CATALOG_DATABASE, id, &text);
2456         if (r < 0)
2457                 return r;
2458
2459         t = replace_var(text, lookup_field, j);
2460         if (!t)
2461                 return -ENOMEM;
2462
2463         *ret = t;
2464         return 0;
2465 }
2466
2467 _public_ int sd_journal_get_catalog_for_message_id(sd_id128_t id, char **ret) {
2468         if (!ret)
2469                 return -EINVAL;
2470
2471         return catalog_get(CATALOG_DATABASE, id, ret);
2472 }
2473
2474 _public_ int sd_journal_set_data_threshold(sd_journal *j, size_t sz) {
2475         if (!j)
2476                 return -EINVAL;
2477
2478         j->data_threshold = sz;
2479         return 0;
2480 }
2481
2482 _public_ int sd_journal_get_data_threshold(sd_journal *j, size_t *sz) {
2483         if (!j)
2484                 return -EINVAL;
2485         if (!sz)
2486                 return -EINVAL;
2487
2488         *sz = j->data_threshold;
2489         return 0;
2490 }