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
  29 #include "sd-journal.h"
  30 #include "journal-def.h"
  31 #include "journal-file.h"
  32 #include "hashmap.h"
  33 #include "list.h"
  34 #include "path-util.h"
  35 #include "lookup3.h"
  36 #include "compress.h"
  37 #include "journal-internal.h"
  38
  39 #define JOURNAL_FILES_MAX 1024
  40
  41 static void detach_location(sd_journal *j) {
  42         Iterator i;
  43         JournalFile *f;
  44
  45         assert(j);
  46
  47         j->current_file = NULL;
  48         j->current_field = 0;
  49
  50         HASHMAP_FOREACH(f, j->files, i)
  51                 f->current_offset = 0;
  52 }
  53
  54 static void reset_location(sd_journal *j) {
  55         assert(j);
  56
  57         detach_location(j);
  58         zero(j->current_location);
  59 }
  60
  61 static void init_location(Location *l, JournalFile *f, Object *o) {
  62         assert(l);
  63         assert(f);
  64         assert(o->object.type == OBJECT_ENTRY);
  65
  66         l->type = LOCATION_DISCRETE;
  67         l->seqnum = le64toh(o->entry.seqnum);
  68         l->seqnum_id = f->header->seqnum_id;
  69         l->realtime = le64toh(o->entry.realtime);
  70         l->monotonic = le64toh(o->entry.monotonic);
  71         l->boot_id = o->entry.boot_id;
  72         l->xor_hash = le64toh(o->entry.xor_hash);
  73
  74         l->seqnum_set = l->realtime_set = l->monotonic_set = l->xor_hash_set = true;
  75 }
  76
  77 static void set_location(sd_journal *j, JournalFile *f, Object *o, uint64_t offset) {
  78         assert(j);
  79         assert(f);
  80         assert(o);
  81
  82         init_location(&j->current_location, f, o);
  83
  84         j->current_file = f;
  85         j->current_field = 0;
  86
  87         f->current_offset = offset;
  88 }
  89
  90 static int match_is_valid(const void *data, size_t size) {
  91         const char *b, *p;
  92
  93         assert(data);
  94
  95         if (size < 2)
  96                 return false;
  97
  98         if (startswith(data, "__"))
  99                 return false;
 100
 101         b = data;
 102         for (p = b; p < b + size; p++) {
 103
 104                 if (*p == '=')
 105                         return p > b;
 106
 107                 if (*p == '_')
 108                         continue;
 109
 110                 if (*p >= 'A' && *p <= 'Z')
 111                         continue;
 112
 113                 if (*p >= '0' && *p <= '9')
 114                         continue;
 115
 116                 return false;
 117         }
 118
 119         return false;
 120 }
 121
 122 static bool same_field(const void *_a, size_t s, const void *_b, size_t t) {
 123         const uint8_t *a = _a, *b = _b;
 124         size_t j;
 125
 126         for (j = 0; j < s && j < t; j++) {
 127
 128                 if (a[j] != b[j])
 129                         return false;
 130
 131                 if (a[j] == '=')
 132                         return true;
 133         }
 134
 135         return true;
 136 }
 137
 138 static Match *match_new(Match *p, MatchType t) {
 139         Match *m;
 140
 141         m = new0(Match, 1);
 142         if (!m)
 143                 return NULL;
 144
 145         m->type = t;
 146
 147         if (p) {
 148                 m->parent = p;
 149                 LIST_PREPEND(Match, matches, p->matches, m);
 150         }
 151
 152         return m;
 153 }
 154
 155 static void match_free(Match *m) {
 156         assert(m);
 157
 158         while (m->matches)
 159                 match_free(m->matches);
 160
 161         if (m->parent)
 162                 LIST_REMOVE(Match, matches, m->parent->matches, m);
 163
 164         free(m->data);
 165         free(m);
 166 }
 167
 168 static void match_free_if_empty(Match *m) {
 169         assert(m);
 170
 171         if (m->matches)
 172                 return;
 173
 174         match_free(m);
 175 }
 176
 177 _public_ int sd_journal_add_match(sd_journal *j, const void *data, size_t size) {
 178         Match *l2, *l3, *add_here = NULL, *m;
 179         le64_t le_hash;
 180
 181         if (!j)
 182                 return -EINVAL;
 183
 184         if (!data)
 185                 return -EINVAL;
 186
 187         if (size == 0)
 188                 size = strlen(data);
 189
 190         if (!match_is_valid(data, size))
 191                 return -EINVAL;
 192
 193         /* level 0: OR term
 194          * level 1: AND terms
 195          * level 2: OR terms
 196          * level 3: concrete matches */
 197
 198         if (!j->level0) {
 199                 j->level0 = match_new(NULL, MATCH_OR_TERM);
 200                 if (!j->level0)
 201                         return -ENOMEM;
 202         }
 203
 204         if (!j->level1) {
 205                 j->level1 = match_new(j->level0, MATCH_AND_TERM);
 206                 if (!j->level1)
 207                         return -ENOMEM;
 208         }
 209
 210         assert(j->level0->type == MATCH_OR_TERM);
 211         assert(j->level1->type == MATCH_AND_TERM);
 212
 213         le_hash = htole64(hash64(data, size));
 214
 215         LIST_FOREACH(matches, l2, j->level1->matches) {
 216                 assert(l2->type == MATCH_OR_TERM);
 217
 218                 LIST_FOREACH(matches, l3, l2->matches) {
 219                         assert(l3->type == MATCH_DISCRETE);
 220
 221                         /* Exactly the same match already? Then ignore
 222                          * this addition */
 223                         if (l3->le_hash == le_hash &&
 224                             l3->size == size &&
 225                             memcmp(l3->data, data, size) == 0)
 226                                 return 0;
 227
 228                         /* Same field? Then let's add this to this OR term */
 229                         if (same_field(data, size, l3->data, l3->size)) {
 230                                 add_here = l2;
 231                                 break;
 232                         }
 233                 }
 234
 235                 if (add_here)
 236                         break;
 237         }
 238
 239         if (!add_here) {
 240                 add_here = match_new(j->level1, MATCH_OR_TERM);
 241                 if (!add_here)
 242                         goto fail;
 243         }
 244
 245         m = match_new(add_here, MATCH_DISCRETE);
 246         if (!m)
 247                 goto fail;
 248
 249         m->le_hash = le_hash;
 250         m->size = size;
 251         m->data = memdup(data, size);
 252         if (!m->data)
 253                 goto fail;
 254
 255         detach_location(j);
 256
 257         return 0;
 258
 259 fail:
 260         if (add_here)
 261                 match_free_if_empty(add_here);
 262
 263         if (j->level1)
 264                 match_free_if_empty(j->level1);
 265
 266         if (j->level0)
 267                 match_free_if_empty(j->level0);
 268
 269         return -ENOMEM;
 270 }
 271
 272 _public_ int sd_journal_add_disjunction(sd_journal *j) {
 273         Match *m;
 274
 275         assert(j);
 276
 277         if (!j->level0)
 278                 return 0;
 279
 280         if (!j->level1)
 281                 return 0;
 282
 283         if (!j->level1->matches)
 284                 return 0;
 285
 286         m = match_new(j->level0, MATCH_AND_TERM);
 287         if (!m)
 288                 return -ENOMEM;
 289
 290         j->level1 = m;
 291         return 0;
 292 }
 293
 294 static char *match_make_string(Match *m) {
 295         char *p, *r;
 296         Match *i;
 297         bool enclose = false;
 298
 299         if (!m)
 300                 return strdup("");
 301
 302         if (m->type == MATCH_DISCRETE)
 303                 return strndup(m->data, m->size);
 304
 305         p = NULL;
 306         LIST_FOREACH(matches, i, m->matches) {
 307                 char *t, *k;
 308
 309                 t = match_make_string(i);
 310                 if (!t) {
 311                         free(p);
 312                         return NULL;
 313                 }
 314
 315                 if (p) {
 316                         k = strjoin(p, m->type == MATCH_OR_TERM ? " OR " : " AND ", t, NULL);
 317                         free(p);
 318                         free(t);
 319
 320                         if (!k)
 321                                 return NULL;
 322
 323                         p = k;
 324
 325                         enclose = true;
 326                 } else {
 327                         free(p);
 328                         p = t;
 329                 }
 330         }
 331
 332         if (enclose) {
 333                 r = strjoin("(", p, ")", NULL);
 334                 free(p);
 335                 return r;
 336         }
 337
 338         return p;
 339 }
 340
 341 char *journal_make_match_string(sd_journal *j) {
 342         assert(j);
 343
 344         return match_make_string(j->level0);
 345 }
 346
 347 _public_ void sd_journal_flush_matches(sd_journal *j) {
 348
 349         if (!j)
 350                 return;
 351
 352         if (j->level0)
 353                 match_free(j->level0);
 354
 355         j->level0 = j->level1 = NULL;
 356
 357         detach_location(j);
 358 }
 359
 360 static int compare_order(JournalFile *af, Object *ao,
 361                          JournalFile *bf, Object *bo) {
 362
 363         uint64_t a, b;
 364
 365         assert(af);
 366         assert(ao);
 367         assert(bf);
 368         assert(bo);
 369
 370         /* We operate on two different files here, hence we can access
 371          * two objects at the same time, which we normally can't.
 372          *
 373          * If contents and timestamps match, these entries are
 374          * identical, even if the seqnum does not match */
 375
 376         if (sd_id128_equal(ao->entry.boot_id, bo->entry.boot_id) &&
 377             ao->entry.monotonic == bo->entry.monotonic &&
 378             ao->entry.realtime == bo->entry.realtime &&
 379             ao->entry.xor_hash == bo->entry.xor_hash)
 380                 return 0;
 381
 382         if (sd_id128_equal(af->header->seqnum_id, bf->header->seqnum_id)) {
 383
 384                 /* If this is from the same seqnum source, compare
 385                  * seqnums */
 386                 a = le64toh(ao->entry.seqnum);
 387                 b = le64toh(bo->entry.seqnum);
 388
 389                 if (a < b)
 390                         return -1;
 391                 if (a > b)
 392                         return 1;
 393
 394                 /* Wow! This is weird, different data but the same
 395                  * seqnums? Something is borked, but let's make the
 396                  * best of it and compare by time. */
 397         }
 398
 399         if (sd_id128_equal(ao->entry.boot_id, bo->entry.boot_id)) {
 400
 401                 /* If the boot id matches compare monotonic time */
 402                 a = le64toh(ao->entry.monotonic);
 403                 b = le64toh(bo->entry.monotonic);
 404
 405                 if (a < b)
 406                         return -1;
 407                 if (a > b)
 408                         return 1;
 409         }
 410
 411         /* Otherwise compare UTC time */
 412         a = le64toh(ao->entry.realtime);
 413         b = le64toh(bo->entry.realtime);
 414
 415         if (a < b)
 416                 return -1;
 417         if (a > b)
 418                 return 1;
 419
 420         /* Finally, compare by contents */
 421         a = le64toh(ao->entry.xor_hash);
 422         b = le64toh(bo->entry.xor_hash);
 423
 424         if (a < b)
 425                 return -1;
 426         if (a > b)
 427                 return 1;
 428
 429         return 0;
 430 }
 431
 432 static int compare_with_location(JournalFile *af, Object *ao, Location *l) {
 433         uint64_t a;
 434
 435         assert(af);
 436         assert(ao);
 437         assert(l);
 438         assert(l->type == LOCATION_DISCRETE);
 439
 440         if (l->monotonic_set &&
 441             sd_id128_equal(ao->entry.boot_id, l->boot_id) &&
 442             l->realtime_set &&
 443             le64toh(ao->entry.realtime) == l->realtime &&
 444             l->xor_hash_set &&
 445             le64toh(ao->entry.xor_hash) == l->xor_hash)
 446                 return 0;
 447
 448         if (l->seqnum_set &&
 449             sd_id128_equal(af->header->seqnum_id, l->seqnum_id)) {
 450
 451                 a = le64toh(ao->entry.seqnum);
 452
 453                 if (a < l->seqnum)
 454                         return -1;
 455                 if (a > l->seqnum)
 456                         return 1;
 457         }
 458
 459         if (l->monotonic_set &&
 460             sd_id128_equal(ao->entry.boot_id, l->boot_id)) {
 461
 462                 a = le64toh(ao->entry.monotonic);
 463
 464                 if (a < l->monotonic)
 465                         return -1;
 466                 if (a > l->monotonic)
 467                         return 1;
 468         }
 469
 470         if (l->realtime_set) {
 471
 472                 a = le64toh(ao->entry.realtime);
 473
 474                 if (a < l->realtime)
 475                         return -1;
 476                 if (a > l->realtime)
 477                         return 1;
 478         }
 479
 480         if (l->xor_hash_set) {
 481                 a = le64toh(ao->entry.xor_hash);
 482
 483                 if (a < l->xor_hash)
 484                         return -1;
 485                 if (a > l->xor_hash)
 486                         return 1;
 487         }
 488
 489         return 0;
 490 }
 491
 492 static int next_for_match(
 493                 sd_journal *j,
 494                 Match *m,
 495                 JournalFile *f,
 496                 uint64_t after_offset,
 497                 direction_t direction,
 498                 Object **ret,
 499                 uint64_t *offset) {
 500
 501         int r;
 502         uint64_t np = 0;
 503         Object *n;
 504
 505         assert(j);
 506         assert(m);
 507         assert(f);
 508
 509         if (m->type == MATCH_DISCRETE) {
 510                 uint64_t dp;
 511
 512                 r = journal_file_find_data_object_with_hash(f, m->data, m->size, le64toh(m->le_hash), NULL, &dp);
 513                 if (r <= 0)
 514                         return r;
 515
 516                 return journal_file_move_to_entry_by_offset_for_data(f, dp, after_offset, direction, ret, offset);
 517
 518         } else if (m->type == MATCH_OR_TERM) {
 519                 Match *i;
 520
 521                 /* Find the earliest match beyond after_offset */
 522
 523                 LIST_FOREACH(matches, i, m->matches) {
 524                         uint64_t cp;
 525
 526                         r = next_for_match(j, i, f, after_offset, direction, NULL, &cp);
 527                         if (r < 0)
 528                                 return r;
 529                         else if (r > 0) {
 530                                 if (np == 0 || (direction == DIRECTION_DOWN ? np > cp : np < cp))
 531                                         np = cp;
 532                         }
 533                 }
 534
 535         } else if (m->type == MATCH_AND_TERM) {
 536                 Match *i;
 537                 bool continue_looking;
 538
 539                 /* Always jump to the next matching entry and repeat
 540                  * this until we fine and offset that matches for all
 541                  * matches. */
 542
 543                 if (!m->matches)
 544                         return 0;
 545
 546                 np = 0;
 547                 do {
 548                         continue_looking = false;
 549
 550                         LIST_FOREACH(matches, i, m->matches) {
 551                                 uint64_t cp, limit;
 552
 553                                 if (np == 0)
 554                                         limit = after_offset;
 555                                 else if (direction == DIRECTION_DOWN)
 556                                         limit = MAX(np, after_offset);
 557                                 else
 558                                         limit = MIN(np, after_offset);
 559
 560                                 r = next_for_match(j, i, f, limit, direction, NULL, &cp);
 561                                 if (r <= 0)
 562                                         return r;
 563
 564                                 if ((direction == DIRECTION_DOWN ? cp >= after_offset : cp <= after_offset) &&
 565                                     (np == 0 || (direction == DIRECTION_DOWN ? cp > np : np < cp))) {
 566                                         np = cp;
 567                                         continue_looking = true;
 568                                 }
 569                         }
 570
 571                 } while (continue_looking);
 572         }
 573
 574         if (np == 0)
 575                 return 0;
 576
 577         r = journal_file_move_to_object(f, OBJECT_ENTRY, np, &n);
 578         if (r < 0)
 579                 return r;
 580
 581         if (ret)
 582                 *ret = n;
 583         if (offset)
 584                 *offset = np;
 585
 586         return 1;
 587 }
 588
 589 static int find_location_for_match(
 590                 sd_journal *j,
 591                 Match *m,
 592                 JournalFile *f,
 593                 direction_t direction,
 594                 Object **ret,
 595                 uint64_t *offset) {
 596
 597         int r;
 598
 599         assert(j);
 600         assert(m);
 601         assert(f);
 602
 603         if (m->type == MATCH_DISCRETE) {
 604                 uint64_t dp;
 605
 606                 r = journal_file_find_data_object_with_hash(f, m->data, m->size, le64toh(m->le_hash), NULL, &dp);
 607                 if (r <= 0)
 608                         return r;
 609
 610                 /* FIXME: missing: find by monotonic */
 611
 612                 if (j->current_location.type == LOCATION_HEAD)
 613                         return journal_file_next_entry_for_data(f, NULL, 0, dp, DIRECTION_DOWN, ret, offset);
 614                 if (j->current_location.type == LOCATION_TAIL)
 615                         return journal_file_next_entry_for_data(f, NULL, 0, dp, DIRECTION_UP, ret, offset);
 616                 if (j->current_location.seqnum_set && sd_id128_equal(j->current_location.seqnum_id, f->header->seqnum_id))
 617                         return journal_file_move_to_entry_by_seqnum_for_data(f, dp, j->current_location.seqnum, direction, ret, offset);
 618                 if (j->current_location.monotonic_set) {
 619                         r = journal_file_move_to_entry_by_monotonic_for_data(f, dp, j->current_location.boot_id, j->current_location.monotonic, direction, ret, offset);
 620                         if (r != -ENOENT)
 621                                 return r;
 622                 }
 623                 if (j->current_location.realtime_set)
 624                         return journal_file_move_to_entry_by_realtime_for_data(f, dp, j->current_location.realtime, direction, ret, offset);
 625
 626                 return journal_file_next_entry_for_data(f, NULL, 0, dp, direction, ret, offset);
 627
 628         } else if (m->type == MATCH_OR_TERM) {
 629                 uint64_t np = 0;
 630                 Object *n;
 631                 Match *i;
 632
 633                 /* Find the earliest match */
 634
 635                 LIST_FOREACH(matches, i, m->matches) {
 636                         uint64_t cp;
 637
 638                         r = find_location_for_match(j, i, f, direction, NULL, &cp);
 639                         if (r < 0)
 640                                 return r;
 641                         else if (r > 0) {
 642                                 if (np == 0 || (direction == DIRECTION_DOWN ? np > cp : np < cp))
 643                                         np = cp;
 644                         }
 645                 }
 646
 647                 if (np == 0)
 648                         return 0;
 649
 650                 r = journal_file_move_to_object(f, OBJECT_ENTRY, np, &n);
 651                 if (r < 0)
 652                         return r;
 653
 654                 if (ret)
 655                         *ret = n;
 656                 if (offset)
 657                         *offset = np;
 658
 659                 return 1;
 660
 661         } else {
 662                 Match *i;
 663                 uint64_t np = 0;
 664
 665                 assert(m->type == MATCH_AND_TERM);
 666
 667                 /* First jump to the last match, and then find the
 668                  * next one where all matches match */
 669
 670                 if (!m->matches)
 671                         return 0;
 672
 673                 LIST_FOREACH(matches, i, m->matches) {
 674                         uint64_t cp;
 675
 676                         r = find_location_for_match(j, i, f, direction, NULL, &cp);
 677                         if (r <= 0)
 678                                 return r;
 679
 680                         if (np == 0 || (direction == DIRECTION_DOWN ? np < cp : np > cp))
 681                                 np = cp;
 682                 }
 683
 684                 return next_for_match(j, m, f, np, direction, ret, offset);
 685         }
 686 }
 687
 688 static int find_location_with_matches(
 689                 sd_journal *j,
 690                 JournalFile *f,
 691                 direction_t direction,
 692                 Object **ret,
 693                 uint64_t *offset) {
 694
 695         int r;
 696
 697         assert(j);
 698         assert(f);
 699         assert(ret);
 700         assert(offset);
 701
 702         if (!j->level0) {
 703                 /* No matches is simple */
 704
 705                 if (j->current_location.type == LOCATION_HEAD)
 706                         return journal_file_next_entry(f, NULL, 0, DIRECTION_DOWN, ret, offset);
 707                 if (j->current_location.type == LOCATION_TAIL)
 708                         return journal_file_next_entry(f, NULL, 0, DIRECTION_UP, ret, offset);
 709                 if (j->current_location.seqnum_set && sd_id128_equal(j->current_location.seqnum_id, f->header->seqnum_id))
 710                         return journal_file_move_to_entry_by_seqnum(f, j->current_location.seqnum, direction, ret, offset);
 711                 if (j->current_location.monotonic_set) {
 712                         r = journal_file_move_to_entry_by_monotonic(f, j->current_location.boot_id, j->current_location.monotonic, direction, ret, offset);
 713                         if (r != -ENOENT)
 714                                 return r;
 715                 }
 716                 if (j->current_location.realtime_set)
 717                         return journal_file_move_to_entry_by_realtime(f, j->current_location.realtime, direction, ret, offset);
 718
 719                 return journal_file_next_entry(f, NULL, 0, direction, ret, offset);
 720         } else
 721                 return find_location_for_match(j, j->level0, f, direction, ret, offset);
 722 }
 723
 724 static int next_with_matches(
 725                 sd_journal *j,
 726                 JournalFile *f,
 727                 direction_t direction,
 728                 Object **ret,
 729                 uint64_t *offset) {
 730
 731         Object *c;
 732         uint64_t cp;
 733
 734         assert(j);
 735         assert(f);
 736         assert(ret);
 737         assert(offset);
 738
 739         c = *ret;
 740         cp = *offset;
 741
 742         /* No matches is easy. We simple advance the file
 743          * pointer by one. */
 744         if (!j->level0)
 745                 return journal_file_next_entry(f, c, cp, direction, ret, offset);
 746
 747         /* If we have a match then we look for the next matching entry
 748          * with an offset at least one step larger */
 749         return next_for_match(j, j->level0, f, direction == DIRECTION_DOWN ? cp+1 : cp-1, direction, ret, offset);
 750 }
 751
 752 static int next_beyond_location(sd_journal *j, JournalFile *f, direction_t direction, Object **ret, uint64_t *offset) {
 753         Object *c;
 754         uint64_t cp;
 755         int r;
 756
 757         assert(j);
 758         assert(f);
 759
 760         if (f->current_offset > 0) {
 761                 cp = f->current_offset;
 762
 763                 r = journal_file_move_to_object(f, OBJECT_ENTRY, cp, &c);
 764                 if (r < 0)
 765                         return r;
 766
 767                 r = next_with_matches(j, f, direction, &c, &cp);
 768                 if (r <= 0)
 769                         return r;
 770         } else {
 771                 r = find_location_with_matches(j, f, direction, &c, &cp);
 772                 if (r <= 0)
 773                         return r;
 774         }
 775
 776         /* OK, we found the spot, now let's advance until to an entry
 777          * that is actually different from what we were previously
 778          * looking at. This is necessary to handle entries which exist
 779          * in two (or more) journal files, and which shall all be
 780          * suppressed but one. */
 781
 782         for (;;) {
 783                 bool found;
 784
 785                 if (j->current_location.type == LOCATION_DISCRETE) {
 786                         int k;
 787
 788                         k = compare_with_location(f, c, &j->current_location);
 789                         if (direction == DIRECTION_DOWN)
 790                                 found = k > 0;
 791                         else
 792                                 found = k < 0;
 793                 } else
 794                         found = true;
 795
 796                 if (found) {
 797                         if (ret)
 798                                 *ret = c;
 799                         if (offset)
 800                                 *offset = cp;
 801                         return 1;
 802                 }
 803
 804                 r = next_with_matches(j, f, direction, &c, &cp);
 805                 if (r <= 0)
 806                         return r;
 807         }
 808 }
 809
 810 static int real_journal_next(sd_journal *j, direction_t direction) {
 811         JournalFile *f, *new_current = NULL;
 812         Iterator i;
 813         int r;
 814         uint64_t new_offset = 0;
 815         Object *new_entry = NULL;
 816
 817         if (!j)
 818                 return -EINVAL;
 819
 820         HASHMAP_FOREACH(f, j->files, i) {
 821                 Object *o;
 822                 uint64_t p;
 823                 bool found;
 824
 825                 r = next_beyond_location(j, f, direction, &o, &p);
 826                 if (r < 0) {
 827                         log_debug("Can't iterate through %s, ignoring: %s", f->path, strerror(-r));
 828                         continue;
 829                 } else if (r == 0)
 830                         continue;
 831
 832                 if (!new_current)
 833                         found = true;
 834                 else {
 835                         int k;
 836
 837                         k = compare_order(f, o, new_current, new_entry);
 838
 839                         if (direction == DIRECTION_DOWN)
 840                                 found = k < 0;
 841                         else
 842                                 found = k > 0;
 843                 }
 844
 845                 if (found) {
 846                         new_current = f;
 847                         new_entry = o;
 848                         new_offset = p;
 849                 }
 850         }
 851
 852         if (!new_current)
 853                 return 0;
 854
 855         set_location(j, new_current, new_entry, new_offset);
 856
 857         return 1;
 858 }
 859
 860 _public_ int sd_journal_next(sd_journal *j) {
 861         return real_journal_next(j, DIRECTION_DOWN);
 862 }
 863
 864 _public_ int sd_journal_previous(sd_journal *j) {
 865         return real_journal_next(j, DIRECTION_UP);
 866 }
 867
 868 static int real_journal_next_skip(sd_journal *j, direction_t direction, uint64_t skip) {
 869         int c = 0, r;
 870
 871         if (!j)
 872                 return -EINVAL;
 873
 874         if (skip == 0) {
 875                 /* If this is not a discrete skip, then at least
 876                  * resolve the current location */
 877                 if (j->current_location.type != LOCATION_DISCRETE)
 878                         return real_journal_next(j, direction);
 879
 880                 return 0;
 881         }
 882
 883         do {
 884                 r = real_journal_next(j, direction);
 885                 if (r < 0)
 886                         return r;
 887
 888                 if (r == 0)
 889                         return c;
 890
 891                 skip--;
 892                 c++;
 893         } while (skip > 0);
 894
 895         return c;
 896 }
 897
 898 _public_ int sd_journal_next_skip(sd_journal *j, uint64_t skip) {
 899         return real_journal_next_skip(j, DIRECTION_DOWN, skip);
 900 }
 901
 902 _public_ int sd_journal_previous_skip(sd_journal *j, uint64_t skip) {
 903         return real_journal_next_skip(j, DIRECTION_UP, skip);
 904 }
 905
 906 _public_ int sd_journal_get_cursor(sd_journal *j, char **cursor) {
 907         Object *o;
 908         int r;
 909         char bid[33], sid[33];
 910
 911         if (!j)
 912                 return -EINVAL;
 913         if (!cursor)
 914                 return -EINVAL;
 915
 916         if (!j->current_file || j->current_file->current_offset <= 0)
 917                 return -EADDRNOTAVAIL;
 918
 919         r = journal_file_move_to_object(j->current_file, OBJECT_ENTRY, j->current_file->current_offset, &o);
 920         if (r < 0)
 921                 return r;
 922
 923         sd_id128_to_string(j->current_file->header->seqnum_id, sid);
 924         sd_id128_to_string(o->entry.boot_id, bid);
 925
 926         if (asprintf(cursor,
 927                      "s=%s;i=%llx;b=%s;m=%llx;t=%llx;x=%llx;p=%s",
 928                      sid, (unsigned long long) le64toh(o->entry.seqnum),
 929                      bid, (unsigned long long) le64toh(o->entry.monotonic),
 930                      (unsigned long long) le64toh(o->entry.realtime),
 931                      (unsigned long long) le64toh(o->entry.xor_hash),
 932                      path_get_file_name(j->current_file->path)) < 0)
 933                 return -ENOMEM;
 934
 935         return 1;
 936 }
 937
 938 _public_ int sd_journal_seek_cursor(sd_journal *j, const char *cursor) {
 939         char *w;
 940         size_t l;
 941         char *state;
 942         unsigned long long seqnum, monotonic, realtime, xor_hash;
 943         bool
 944                 seqnum_id_set = false,
 945                 seqnum_set = false,
 946                 boot_id_set = false,
 947                 monotonic_set = false,
 948                 realtime_set = false,
 949                 xor_hash_set = false;
 950         sd_id128_t seqnum_id, boot_id;
 951
 952         if (!j)
 953                 return -EINVAL;
 954         if (!cursor)
 955                 return -EINVAL;
 956
 957         FOREACH_WORD_SEPARATOR(w, l, cursor, ";", state) {
 958                 char *item;
 959                 int k = 0;
 960
 961                 if (l < 2 || w[1] != '=')
 962                         return -EINVAL;
 963
 964                 item = strndup(w, l);
 965                 if (!item)
 966                         return -ENOMEM;
 967
 968                 switch (w[0]) {
 969
 970                 case 's':
 971                         seqnum_id_set = true;
 972                         k = sd_id128_from_string(w+2, &seqnum_id);
 973                         break;
 974
 975                 case 'i':
 976                         seqnum_set = true;
 977                         if (sscanf(w+2, "%llx", &seqnum) != 1)
 978                                 k = -EINVAL;
 979                         break;
 980
 981                 case 'b':
 982                         boot_id_set = true;
 983                         k = sd_id128_from_string(w+2, &boot_id);
 984                         break;
 985
 986                 case 'm':
 987                         monotonic_set = true;
 988                         if (sscanf(w+2, "%llx", &monotonic) != 1)
 989                                 k = -EINVAL;
 990                         break;
 991
 992                 case 't':
 993                         realtime_set = true;
 994                         if (sscanf(w+2, "%llx", &realtime) != 1)
 995                                 k = -EINVAL;
 996                         break;
 997
 998                 case 'x':
 999                         xor_hash_set = true;
1000                         if (sscanf(w+2, "%llx", &xor_hash) != 1)
1001                                 k = -EINVAL;
1002                         break;
1003                 }
1004
1005                 free(item);
1006
1007                 if (k < 0)
1008                         return k;
1009         }
1010
1011         if ((!seqnum_set || !seqnum_id_set) &&
1012             (!monotonic_set || !boot_id_set) &&
1013             !realtime_set)
1014                 return -EINVAL;
1015
1016         reset_location(j);
1017
1018         j->current_location.type = LOCATION_DISCRETE;
1019
1020         if (realtime_set) {
1021                 j->current_location.realtime = (uint64_t) realtime;
1022                 j->current_location.realtime_set = true;
1023         }
1024
1025         if (seqnum_set && seqnum_id_set) {
1026                 j->current_location.seqnum = (uint64_t) seqnum;
1027                 j->current_location.seqnum_id = seqnum_id;
1028                 j->current_location.seqnum_set = true;
1029         }
1030
1031         if (monotonic_set && boot_id_set) {
1032                 j->current_location.monotonic = (uint64_t) monotonic;
1033                 j->current_location.boot_id = boot_id;
1034                 j->current_location.monotonic_set = true;
1035         }
1036
1037         if (xor_hash_set) {
1038                 j->current_location.xor_hash = (uint64_t) xor_hash;
1039                 j->current_location.xor_hash_set = true;
1040         }
1041
1042         return 0;
1043 }
1044
1045 _public_ int sd_journal_seek_monotonic_usec(sd_journal *j, sd_id128_t boot_id, uint64_t usec) {
1046         if (!j)
1047                 return -EINVAL;
1048
1049         reset_location(j);
1050         j->current_location.type = LOCATION_DISCRETE;
1051         j->current_location.boot_id = boot_id;
1052         j->current_location.monotonic = usec;
1053         j->current_location.monotonic_set = true;
1054
1055         return 0;
1056 }
1057
1058 _public_ int sd_journal_seek_realtime_usec(sd_journal *j, uint64_t usec) {
1059         if (!j)
1060                 return -EINVAL;
1061
1062         reset_location(j);
1063         j->current_location.type = LOCATION_DISCRETE;
1064         j->current_location.realtime = usec;
1065         j->current_location.realtime_set = true;
1066
1067         return 0;
1068 }
1069
1070 _public_ int sd_journal_seek_head(sd_journal *j) {
1071         if (!j)
1072                 return -EINVAL;
1073
1074         reset_location(j);
1075         j->current_location.type = LOCATION_HEAD;
1076
1077         return 0;
1078 }
1079
1080 _public_ int sd_journal_seek_tail(sd_journal *j) {
1081         if (!j)
1082                 return -EINVAL;
1083
1084         reset_location(j);
1085         j->current_location.type = LOCATION_TAIL;
1086
1087         return 0;
1088 }
1089
1090 static int add_file(sd_journal *j, const char *prefix, const char *filename) {
1091         char *path;
1092         int r;
1093         JournalFile *f;
1094
1095         assert(j);
1096         assert(prefix);
1097         assert(filename);
1098
1099         if ((j->flags & SD_JOURNAL_SYSTEM_ONLY) &&
1100             !(streq(filename, "system.journal") ||
1101              (startswith(filename, "system@") && endswith(filename, ".journal"))))
1102                 return 0;
1103
1104         path = strjoin(prefix, "/", filename, NULL);
1105         if (!path)
1106                 return -ENOMEM;
1107
1108         if (hashmap_get(j->files, path)) {
1109                 free(path);
1110                 return 0;
1111         }
1112
1113         if (hashmap_size(j->files) >= JOURNAL_FILES_MAX) {
1114                 log_debug("Too many open journal files, not adding %s, ignoring.", path);
1115                 free(path);
1116                 return 0;
1117         }
1118
1119         r = journal_file_open(path, O_RDONLY, 0, NULL, NULL, &f);
1120         free(path);
1121
1122         if (r < 0) {
1123                 if (errno == ENOENT)
1124                         return 0;
1125
1126                 return r;
1127         }
1128
1129         /* journal_file_dump(f); */
1130
1131         r = hashmap_put(j->files, f->path, f);
1132         if (r < 0) {
1133                 journal_file_close(f);
1134                 return r;
1135         }
1136
1137         j->current_invalidate_counter ++;
1138
1139         log_debug("File %s got added.", f->path);
1140
1141         return 0;
1142 }
1143
1144 static int remove_file(sd_journal *j, const char *prefix, const char *filename) {
1145         char *path;
1146         JournalFile *f;
1147
1148         assert(j);
1149         assert(prefix);
1150         assert(filename);
1151
1152         path = strjoin(prefix, "/", filename, NULL);
1153         if (!path)
1154                 return -ENOMEM;
1155
1156         f = hashmap_get(j->files, path);
1157         free(path);
1158         if (!f)
1159                 return 0;
1160
1161         hashmap_remove(j->files, f->path);
1162         journal_file_close(f);
1163
1164         j->current_invalidate_counter ++;
1165
1166         log_debug("File %s got removed.", f->path);
1167         return 0;
1168 }
1169
1170 static int add_directory(sd_journal *j, const char *prefix, const char *dirname) {
1171         char *path;
1172         int r;
1173         DIR *d;
1174         sd_id128_t id, mid;
1175         Directory *m;
1176
1177         assert(j);
1178         assert(prefix);
1179         assert(dirname);
1180
1181         if ((j->flags & SD_JOURNAL_LOCAL_ONLY) &&
1182             (sd_id128_from_string(dirname, &id) < 0 ||
1183              sd_id128_get_machine(&mid) < 0 ||
1184              !sd_id128_equal(id, mid)))
1185             return 0;
1186
1187         path = strjoin(prefix, "/", dirname, NULL);
1188         if (!path)
1189                 return -ENOMEM;
1190
1191         d = opendir(path);
1192         if (!d) {
1193                 log_debug("Failed to open %s: %m", path);
1194                 free(path);
1195
1196                 if (errno == ENOENT)
1197                         return 0;
1198                 return -errno;
1199         }
1200
1201         m = hashmap_get(j->directories_by_path, path);
1202         if (!m) {
1203                 m = new0(Directory, 1);
1204                 if (!m) {
1205                         closedir(d);
1206                         free(path);
1207                         return -ENOMEM;
1208                 }
1209
1210                 m->is_root = false;
1211                 m->path = path;
1212
1213                 if (hashmap_put(j->directories_by_path, m->path, m) < 0) {
1214                         closedir(d);
1215                         free(m->path);
1216                         free(m);
1217                         return -ENOMEM;
1218                 }
1219
1220                 j->current_invalidate_counter ++;
1221
1222                 log_debug("Directory %s got added.", m->path);
1223
1224         } else if (m->is_root) {
1225                 free (path);
1226                 closedir(d);
1227                 return 0;
1228         }  else
1229                 free(path);
1230
1231         if (m->wd <= 0 && j->inotify_fd >= 0) {
1232
1233                 m->wd = inotify_add_watch(j->inotify_fd, m->path,
1234                                           IN_CREATE|IN_MOVED_TO|IN_MODIFY|IN_ATTRIB|IN_DELETE|
1235                                           IN_DELETE_SELF|IN_MOVE_SELF|IN_UNMOUNT|
1236                                           IN_DONT_FOLLOW|IN_ONLYDIR);
1237
1238                 if (m->wd > 0 && hashmap_put(j->directories_by_wd, INT_TO_PTR(m->wd), m) < 0)
1239                         inotify_rm_watch(j->inotify_fd, m->wd);
1240         }
1241
1242         for (;;) {
1243                 struct dirent buf, *de;
1244
1245                 r = readdir_r(d, &buf, &de);
1246                 if (r != 0 || !de)
1247                         break;
1248
1249                 if (dirent_is_file_with_suffix(de, ".journal")) {
1250                         r = add_file(j, m->path, de->d_name);
1251                         if (r < 0)
1252                                 log_debug("Failed to add file %s/%s: %s", m->path, de->d_name, strerror(-r));
1253                 }
1254         }
1255
1256         closedir(d);
1257
1258         return 0;
1259 }
1260
1261 static int add_root_directory(sd_journal *j, const char *p) {
1262         DIR *d;
1263         Directory *m;
1264         int r;
1265
1266         assert(j);
1267         assert(p);
1268
1269         if ((j->flags & SD_JOURNAL_RUNTIME_ONLY) &&
1270             !path_startswith(p, "/run"))
1271                 return -EINVAL;
1272
1273         d = opendir(p);
1274         if (!d)
1275                 return -errno;
1276
1277         m = hashmap_get(j->directories_by_path, p);
1278         if (!m) {
1279                 m = new0(Directory, 1);
1280                 if (!m) {
1281                         closedir(d);
1282                         return -ENOMEM;
1283                 }
1284
1285                 m->is_root = true;
1286                 m->path = strdup(p);
1287                 if (!m->path) {
1288                         closedir(d);
1289                         free(m);
1290                         return -ENOMEM;
1291                 }
1292
1293                 if (hashmap_put(j->directories_by_path, m->path, m) < 0) {
1294                         closedir(d);
1295                         free(m->path);
1296                         free(m);
1297                         return -ENOMEM;
1298                 }
1299
1300                 j->current_invalidate_counter ++;
1301
1302                 log_debug("Root directory %s got added.", m->path);
1303
1304         } else if (!m->is_root) {
1305                 closedir(d);
1306                 return 0;
1307         }
1308
1309         if (m->wd <= 0 && j->inotify_fd >= 0) {
1310
1311                 m->wd = inotify_add_watch(j->inotify_fd, m->path,
1312                                           IN_CREATE|IN_MOVED_TO|IN_MODIFY|IN_ATTRIB|IN_DELETE|
1313                                           IN_DONT_FOLLOW|IN_ONLYDIR);
1314
1315                 if (m->wd > 0 && hashmap_put(j->directories_by_wd, INT_TO_PTR(m->wd), m) < 0)
1316                         inotify_rm_watch(j->inotify_fd, m->wd);
1317         }
1318
1319         for (;;) {
1320                 struct dirent buf, *de;
1321                 sd_id128_t id;
1322
1323                 r = readdir_r(d, &buf, &de);
1324                 if (r != 0 || !de)
1325                         break;
1326
1327                 if (dirent_is_file_with_suffix(de, ".journal")) {
1328                         r = add_file(j, m->path, de->d_name);
1329                         if (r < 0)
1330                                 log_debug("Failed to add file %s/%s: %s", m->path, de->d_name, strerror(-r));
1331
1332                 } else if ((de->d_type == DT_DIR || de->d_type == DT_UNKNOWN) &&
1333                            sd_id128_from_string(de->d_name, &id) >= 0) {
1334
1335                         r = add_directory(j, m->path, de->d_name);
1336                         if (r < 0)
1337                                 log_debug("Failed to add directory %s/%s: %s", m->path, de->d_name, strerror(-r));
1338                 }
1339         }
1340
1341         closedir(d);
1342
1343         return 0;
1344 }
1345
1346 static int remove_directory(sd_journal *j, Directory *d) {
1347         assert(j);
1348
1349         if (d->wd > 0) {
1350                 hashmap_remove(j->directories_by_wd, INT_TO_PTR(d->wd));
1351
1352                 if (j->inotify_fd >= 0)
1353                         inotify_rm_watch(j->inotify_fd, d->wd);
1354         }
1355
1356         hashmap_remove(j->directories_by_path, d->path);
1357
1358         if (d->is_root)
1359                 log_debug("Root directory %s got removed.", d->path);
1360         else
1361                 log_debug("Directory %s got removed.", d->path);
1362
1363         free(d->path);
1364         free(d);
1365
1366         return 0;
1367 }
1368
1369 static int add_search_paths(sd_journal *j) {
1370
1371         const char search_paths[] =
1372                 "/run/log/journal\0"
1373                 "/var/log/journal\0";
1374         const char *p;
1375
1376         assert(j);
1377
1378         /* We ignore most errors here, since the idea is to only open
1379          * what's actually accessible, and ignore the rest. */
1380
1381         NULSTR_FOREACH(p, search_paths)
1382                 add_root_directory(j, p);
1383
1384         return 0;
1385 }
1386
1387 static int allocate_inotify(sd_journal *j) {
1388         assert(j);
1389
1390         if (j->inotify_fd < 0) {
1391                 j->inotify_fd = inotify_init1(IN_NONBLOCK|IN_CLOEXEC);
1392                 if (j->inotify_fd < 0)
1393                         return -errno;
1394         }
1395
1396         if (!j->directories_by_wd) {
1397                 j->directories_by_wd = hashmap_new(trivial_hash_func, trivial_compare_func);
1398                 if (!j->directories_by_wd)
1399                         return -ENOMEM;
1400         }
1401
1402         return 0;
1403 }
1404
1405 static sd_journal *journal_new(int flags) {
1406         sd_journal *j;
1407
1408         j = new0(sd_journal, 1);
1409         if (!j)
1410                 return NULL;
1411
1412         j->inotify_fd = -1;
1413         j->flags = flags;
1414
1415         j->files = hashmap_new(string_hash_func, string_compare_func);
1416         if (!j->files) {
1417                 free(j);
1418                 return NULL;
1419         }
1420
1421         j->directories_by_path = hashmap_new(string_hash_func, string_compare_func);
1422         if (!j->directories_by_path) {
1423                 hashmap_free(j->files);
1424                 free(j);
1425                 return NULL;
1426         }
1427
1428         return j;
1429 }
1430
1431 _public_ int sd_journal_open(sd_journal **ret, int flags) {
1432         sd_journal *j;
1433         int r;
1434
1435         if (!ret)
1436                 return -EINVAL;
1437
1438         if (flags & ~(SD_JOURNAL_LOCAL_ONLY|
1439                       SD_JOURNAL_RUNTIME_ONLY|
1440                       SD_JOURNAL_SYSTEM_ONLY))
1441                 return -EINVAL;
1442
1443         j = journal_new(flags);
1444         if (!j)
1445                 return -ENOMEM;
1446
1447         r = add_search_paths(j);
1448         if (r < 0)
1449                 goto fail;
1450
1451         *ret = j;
1452         return 0;
1453
1454 fail:
1455         sd_journal_close(j);
1456
1457         return r;
1458 }
1459
1460 _public_ int sd_journal_open_directory(sd_journal **ret, const char *path, int flags) {
1461         sd_journal *j;
1462         int r;
1463
1464         if (!ret)
1465                 return -EINVAL;
1466
1467         if (!path || !path_is_absolute(path))
1468                 return -EINVAL;
1469
1470         if (flags != 0)
1471                 return -EINVAL;
1472
1473         j = journal_new(flags);
1474         if (!j)
1475                 return -ENOMEM;
1476
1477         r = add_root_directory(j, path);
1478         if (r < 0)
1479                 goto fail;
1480
1481         *ret = j;
1482         return 0;
1483
1484 fail:
1485         sd_journal_close(j);
1486
1487         return r;
1488 }
1489
1490 _public_ void sd_journal_close(sd_journal *j) {
1491         Directory *d;
1492         JournalFile *f;
1493
1494         if (!j)
1495                 return;
1496
1497         while ((f = hashmap_steal_first(j->files)))
1498                 journal_file_close(f);
1499
1500         hashmap_free(j->files);
1501
1502         while ((d = hashmap_first(j->directories_by_path)))
1503                 remove_directory(j, d);
1504
1505         while ((d = hashmap_first(j->directories_by_wd)))
1506                 remove_directory(j, d);
1507
1508         hashmap_free(j->directories_by_path);
1509         hashmap_free(j->directories_by_wd);
1510
1511         if (j->inotify_fd >= 0)
1512                 close_nointr_nofail(j->inotify_fd);
1513
1514         sd_journal_flush_matches(j);
1515
1516         free(j);
1517 }
1518
1519 _public_ int sd_journal_get_realtime_usec(sd_journal *j, uint64_t *ret) {
1520         Object *o;
1521         JournalFile *f;
1522         int r;
1523
1524         if (!j)
1525                 return -EINVAL;
1526         if (!ret)
1527                 return -EINVAL;
1528
1529         f = j->current_file;
1530         if (!f)
1531                 return -EADDRNOTAVAIL;
1532
1533         if (f->current_offset <= 0)
1534                 return -EADDRNOTAVAIL;
1535
1536         r = journal_file_move_to_object(f, OBJECT_ENTRY, f->current_offset, &o);
1537         if (r < 0)
1538                 return r;
1539
1540         *ret = le64toh(o->entry.realtime);
1541         return 0;
1542 }
1543
1544 _public_ int sd_journal_get_monotonic_usec(sd_journal *j, uint64_t *ret, sd_id128_t *ret_boot_id) {
1545         Object *o;
1546         JournalFile *f;
1547         int r;
1548         sd_id128_t id;
1549
1550         if (!j)
1551                 return -EINVAL;
1552
1553         f = j->current_file;
1554         if (!f)
1555                 return -EADDRNOTAVAIL;
1556
1557         if (f->current_offset <= 0)
1558                 return -EADDRNOTAVAIL;
1559
1560         r = journal_file_move_to_object(f, OBJECT_ENTRY, f->current_offset, &o);
1561         if (r < 0)
1562                 return r;
1563
1564         if (ret_boot_id)
1565                 *ret_boot_id = o->entry.boot_id;
1566         else {
1567                 r = sd_id128_get_boot(&id);
1568                 if (r < 0)
1569                         return r;
1570
1571                 if (!sd_id128_equal(id, o->entry.boot_id))
1572                         return -ESTALE;
1573         }
1574
1575         if (ret)
1576                 *ret = le64toh(o->entry.monotonic);
1577
1578         return 0;
1579 }
1580
1581 static bool field_is_valid(const char *field) {
1582         const char *p;
1583
1584         assert(field);
1585
1586         if (isempty(field))
1587                 return false;
1588
1589         if (startswith(field, "__"))
1590                 return false;
1591
1592         for (p = field; *p; p++) {
1593
1594                 if (*p == '_')
1595                         continue;
1596
1597                 if (*p >= 'A' && *p <= 'Z')
1598                         continue;
1599
1600                 if (*p >= '0' && *p <= '9')
1601                         continue;
1602
1603                 return false;
1604         }
1605
1606         return true;
1607 }
1608
1609 _public_ int sd_journal_get_data(sd_journal *j, const char *field, const void **data, size_t *size) {
1610         JournalFile *f;
1611         uint64_t i, n;
1612         size_t field_length;
1613         int r;
1614         Object *o;
1615
1616         if (!j)
1617                 return -EINVAL;
1618         if (!field)
1619                 return -EINVAL;
1620         if (!data)
1621                 return -EINVAL;
1622         if (!size)
1623                 return -EINVAL;
1624
1625         if (!field_is_valid(field))
1626                 return -EINVAL;
1627
1628         f = j->current_file;
1629         if (!f)
1630                 return -EADDRNOTAVAIL;
1631
1632         if (f->current_offset <= 0)
1633                 return -EADDRNOTAVAIL;
1634
1635         r = journal_file_move_to_object(f, OBJECT_ENTRY, f->current_offset, &o);
1636         if (r < 0)
1637                 return r;
1638
1639         field_length = strlen(field);
1640
1641         n = journal_file_entry_n_items(o);
1642         for (i = 0; i < n; i++) {
1643                 uint64_t p, l;
1644                 le64_t le_hash;
1645                 size_t t;
1646
1647                 p = le64toh(o->entry.items[i].object_offset);
1648                 le_hash = o->entry.items[i].hash;
1649                 r = journal_file_move_to_object(f, OBJECT_DATA, p, &o);
1650                 if (r < 0)
1651                         return r;
1652
1653                 if (le_hash != o->data.hash)
1654                         return -EBADMSG;
1655
1656                 l = le64toh(o->object.size) - offsetof(Object, data.payload);
1657
1658                 if (o->object.flags & OBJECT_COMPRESSED) {
1659
1660 #ifdef HAVE_XZ
1661                         if (uncompress_startswith(o->data.payload, l,
1662                                                   &f->compress_buffer, &f->compress_buffer_size,
1663                                                   field, field_length, '=')) {
1664
1665                                 uint64_t rsize;
1666
1667                                 if (!uncompress_blob(o->data.payload, l,
1668                                                      &f->compress_buffer, &f->compress_buffer_size, &rsize))
1669                                         return -EBADMSG;
1670
1671                                 *data = f->compress_buffer;
1672                                 *size = (size_t) rsize;
1673
1674                                 return 0;
1675                         }
1676 #else
1677                         return -EPROTONOSUPPORT;
1678 #endif
1679
1680                 } else if (l >= field_length+1 &&
1681                            memcmp(o->data.payload, field, field_length) == 0 &&
1682                            o->data.payload[field_length] == '=') {
1683
1684                         t = (size_t) l;
1685
1686                         if ((uint64_t) t != l)
1687                                 return -E2BIG;
1688
1689                         *data = o->data.payload;
1690                         *size = t;
1691
1692                         return 0;
1693                 }
1694
1695                 r = journal_file_move_to_object(f, OBJECT_ENTRY, f->current_offset, &o);
1696                 if (r < 0)
1697                         return r;
1698         }
1699
1700         return -ENOENT;
1701 }
1702
1703 _public_ int sd_journal_enumerate_data(sd_journal *j, const void **data, size_t *size) {
1704         JournalFile *f;
1705         uint64_t p, l, n;
1706         le64_t le_hash;
1707         int r;
1708         Object *o;
1709         size_t t;
1710
1711         if (!j)
1712                 return -EINVAL;
1713         if (!data)
1714                 return -EINVAL;
1715         if (!size)
1716                 return -EINVAL;
1717
1718         f = j->current_file;
1719         if (!f)
1720                 return -EADDRNOTAVAIL;
1721
1722         if (f->current_offset <= 0)
1723                 return -EADDRNOTAVAIL;
1724
1725         r = journal_file_move_to_object(f, OBJECT_ENTRY, f->current_offset, &o);
1726         if (r < 0)
1727                 return r;
1728
1729         n = journal_file_entry_n_items(o);
1730         if (j->current_field >= n)
1731                 return 0;
1732
1733         p = le64toh(o->entry.items[j->current_field].object_offset);
1734         le_hash = o->entry.items[j->current_field].hash;
1735         r = journal_file_move_to_object(f, OBJECT_DATA, p, &o);
1736         if (r < 0)
1737                 return r;
1738
1739         if (le_hash != o->data.hash)
1740                 return -EBADMSG;
1741
1742         l = le64toh(o->object.size) - offsetof(Object, data.payload);
1743         t = (size_t) l;
1744
1745         /* We can't read objects larger than 4G on a 32bit machine */
1746         if ((uint64_t) t != l)
1747                 return -E2BIG;
1748
1749         if (o->object.flags & OBJECT_COMPRESSED) {
1750 #ifdef HAVE_XZ
1751                 uint64_t rsize;
1752
1753                 if (!uncompress_blob(o->data.payload, l, &f->compress_buffer, &f->compress_buffer_size, &rsize))
1754                         return -EBADMSG;
1755
1756                 *data = f->compress_buffer;
1757                 *size = (size_t) rsize;
1758 #else
1759                 return -EPROTONOSUPPORT;
1760 #endif
1761         } else {
1762                 *data = o->data.payload;
1763                 *size = t;
1764         }
1765
1766         j->current_field ++;
1767
1768         return 1;
1769 }
1770
1771 _public_ void sd_journal_restart_data(sd_journal *j) {
1772         if (!j)
1773                 return;
1774
1775         j->current_field = 0;
1776 }
1777
1778 _public_ int sd_journal_get_fd(sd_journal *j) {
1779         int r;
1780
1781         if (!j)
1782                 return -EINVAL;
1783
1784         if (j->inotify_fd >= 0)
1785                 return j->inotify_fd;
1786
1787         r = allocate_inotify(j);
1788         if (r < 0)
1789                 return r;
1790
1791         /* Iterate through all dirs again, to add them to the
1792          * inotify */
1793         r = add_search_paths(j);
1794         if (r < 0)
1795                 return r;
1796
1797         return j->inotify_fd;
1798 }
1799
1800 static void process_inotify_event(sd_journal *j, struct inotify_event *e) {
1801         Directory *d;
1802         int r;
1803
1804         assert(j);
1805         assert(e);
1806
1807         /* Is this a subdirectory we watch? */
1808         d = hashmap_get(j->directories_by_wd, INT_TO_PTR(e->wd));
1809         if (d) {
1810                 sd_id128_t id;
1811
1812                 if (!(e->mask & IN_ISDIR) && e->len > 0 && endswith(e->name, ".journal")) {
1813
1814                         /* Event for a journal file */
1815
1816                         if (e->mask & (IN_CREATE|IN_MOVED_TO|IN_MODIFY|IN_ATTRIB)) {
1817                                 r = add_file(j, d->path, e->name);
1818                                 if (r < 0)
1819                                         log_debug("Failed to add file %s/%s: %s", d->path, e->name, strerror(-r));
1820
1821                         } else if (e->mask & (IN_DELETE|IN_UNMOUNT)) {
1822
1823                                 r = remove_file(j, d->path, e->name);
1824                                 if (r < 0)
1825                                         log_debug("Failed to remove file %s/%s: %s", d->path, e->name, strerror(-r));
1826                         }
1827
1828                 } else if (!d->is_root && e->len == 0) {
1829
1830                         /* Event for a subdirectory */
1831
1832                         if (e->mask & (IN_DELETE_SELF|IN_MOVE_SELF|IN_UNMOUNT)) {
1833                                 r = remove_directory(j, d);
1834                                 if (r < 0)
1835                                         log_debug("Failed to remove directory %s: %s", d->path, strerror(-r));
1836                         }
1837
1838
1839                 } else if (d->is_root && (e->mask & IN_ISDIR) && e->len > 0 && sd_id128_from_string(e->name, &id) >= 0) {
1840
1841                         /* Event for root directory */
1842
1843                         if (e->mask & (IN_CREATE|IN_MOVED_TO|IN_MODIFY|IN_ATTRIB)) {
1844                                 r = add_directory(j, d->path, e->name);
1845                                 if (r < 0)
1846                                         log_debug("Failed to add directory %s/%s: %s", d->path, e->name, strerror(-r));
1847                         }
1848                 }
1849
1850                 return;
1851         }
1852
1853         if (e->mask & IN_IGNORED)
1854                 return;
1855
1856         log_warning("Unknown inotify event.");
1857 }
1858
1859 static int determine_change(sd_journal *j) {
1860         bool b;
1861
1862         assert(j);
1863
1864         b = j->current_invalidate_counter != j->last_invalidate_counter;
1865         j->last_invalidate_counter = j->current_invalidate_counter;
1866
1867         return b ? SD_JOURNAL_INVALIDATE : SD_JOURNAL_APPEND;
1868 }
1869
1870 _public_ int sd_journal_process(sd_journal *j) {
1871         uint8_t buffer[sizeof(struct inotify_event) + FILENAME_MAX] _alignas_(struct inotify_event);
1872         bool got_something = false;
1873
1874         if (!j)
1875                 return -EINVAL;
1876
1877         for (;;) {
1878                 struct inotify_event *e;
1879                 ssize_t l;
1880
1881                 l = read(j->inotify_fd, buffer, sizeof(buffer));
1882                 if (l < 0) {
1883                         if (errno == EAGAIN || errno == EINTR)
1884                                 return got_something ? determine_change(j) : SD_JOURNAL_NOP;
1885
1886                         return -errno;
1887                 }
1888
1889                 got_something = true;
1890
1891                 e = (struct inotify_event*) buffer;
1892                 while (l > 0) {
1893                         size_t step;
1894
1895                         process_inotify_event(j, e);
1896
1897                         step = sizeof(struct inotify_event) + e->len;
1898                         assert(step <= (size_t) l);
1899
1900                         e = (struct inotify_event*) ((uint8_t*) e + step);
1901                         l -= step;
1902                 }
1903         }
1904
1905         return determine_change(j);
1906 }
1907
1908 _public_ int sd_journal_wait(sd_journal *j, uint64_t timeout_usec) {
1909         int r;
1910
1911         assert(j);
1912
1913         if (j->inotify_fd < 0) {
1914
1915                 /* This is the first invocation, hence create the
1916                  * inotify watch */
1917                 r = sd_journal_get_fd(j);
1918                 if (r < 0)
1919                         return r;
1920
1921                 /* The journal might have changed since the context
1922                  * object was created and we weren't watching before,
1923                  * hence don't wait for anything, and return
1924                  * immediately. */
1925                 return determine_change(j);
1926         }
1927
1928         do {
1929                 r = fd_wait_for_event(j->inotify_fd, POLLIN, timeout_usec);
1930         } while (r == -EINTR);
1931
1932         if (r < 0)
1933                 return r;
1934
1935         return sd_journal_process(j);
1936 }
1937
1938 _public_ int sd_journal_get_cutoff_realtime_usec(sd_journal *j, uint64_t *from, uint64_t *to) {
1939         Iterator i;
1940         JournalFile *f;
1941         bool first = true;
1942         int r;
1943
1944         if (!j)
1945                 return -EINVAL;
1946         if (!from && !to)
1947                 return -EINVAL;
1948
1949         HASHMAP_FOREACH(f, j->files, i) {
1950                 usec_t fr, t;
1951
1952                 r = journal_file_get_cutoff_realtime_usec(f, &fr, &t);
1953                 if (r < 0)
1954                         return r;
1955                 if (r == 0)
1956                         continue;
1957
1958                 if (first) {
1959                         if (from)
1960                                 *from = fr;
1961                         if (to)
1962                                 *to = t;
1963                         first = false;
1964                 } else {
1965                         if (from)
1966                                 *from = MIN(fr, *from);
1967                         if (to)
1968                                 *to = MIN(t, *to);
1969                 }
1970         }
1971
1972         return first ? 0 : 1;
1973 }
1974
1975 _public_ int sd_journal_get_cutoff_monotonic_usec(sd_journal *j, sd_id128_t boot_id, uint64_t *from, uint64_t *to) {
1976         Iterator i;
1977         JournalFile *f;
1978         bool first = true;
1979         int r;
1980
1981         if (!j)
1982                 return -EINVAL;
1983         if (!from && !to)
1984                 return -EINVAL;
1985
1986         HASHMAP_FOREACH(f, j->files, i) {
1987                 usec_t fr, t;
1988
1989                 r = journal_file_get_cutoff_monotonic_usec(f, boot_id, &fr, &t);
1990                 if (r < 0)
1991                         return r;
1992                 if (r == 0)
1993                         continue;
1994
1995                 if (first) {
1996                         if (from)
1997                                 *from = fr;
1998                         if (to)
1999                                 *to = t;
2000                         first = false;
2001                 } else {
2002                         if (from)
2003                                 *from = MIN(fr, *from);
2004                         if (to)
2005                                 *to = MIN(t, *to);
2006                 }
2007         }
2008
2009         return first ? 0 : 1;
2010 }
2011
2012 void journal_print_header(sd_journal *j) {
2013         Iterator i;
2014         JournalFile *f;
2015         bool newline = false;
2016
2017         assert(j);
2018
2019         HASHMAP_FOREACH(f, j->files, i) {
2020                 if (newline)
2021                         putchar('\n');
2022                 else
2023                         newline = true;
2024
2025                 journal_file_print_header(f);
2026         }
2027 }
2028
2029 /* _public_ int sd_journal_query_unique(sd_journal *j, const char *field) { */
2030 /*         if (!j) */
2031 /*                 return -EINVAL; */
2032 /*         if (!field) */
2033 /*                 return -EINVAL; */
2034
2035 /*         return -ENOTSUP; */
2036 /* } */
2037
2038 /* _public_ int sd_journal_enumerate_unique(sd_journal *j, const void **data, size_t *l) { */
2039 /*         if (!j) */
2040 /*                 return -EINVAL; */
2041 /*         if (!data) */
2042 /*                 return -EINVAL; */
2043 /*         if (!l) */
2044 /*                 return -EINVAL; */
2045
2046 /*         return -ENOTSUP; */
2047 /* } */
2048
2049 /* _public_ void sd_journal_restart_unique(sd_journal *j) { */
2050 /*         if (!j) */
2051 /*                 return; */
2052 /* } */