chiark / gitweb /
journal: when watching directories actually watch the directories asked for
[elogind.git] / 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_LNK || 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, const char *path) {
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         if (path) {
1416                 j->path = strdup(path);
1417                 if (!j->path) {
1418                         free(j);
1419                         return NULL;
1420                 }
1421         }
1422
1423         j->files = hashmap_new(string_hash_func, string_compare_func);
1424         if (!j->files) {
1425                 free(j->path);
1426                 free(j);
1427                 return NULL;
1428         }
1429
1430         j->directories_by_path = hashmap_new(string_hash_func, string_compare_func);
1431         if (!j->directories_by_path) {
1432                 hashmap_free(j->files);
1433                 free(j->path);
1434                 free(j);
1435                 return NULL;
1436         }
1437
1438         return j;
1439 }
1440
1441 _public_ int sd_journal_open(sd_journal **ret, int flags) {
1442         sd_journal *j;
1443         int r;
1444
1445         if (!ret)
1446                 return -EINVAL;
1447
1448         if (flags & ~(SD_JOURNAL_LOCAL_ONLY|
1449                       SD_JOURNAL_RUNTIME_ONLY|
1450                       SD_JOURNAL_SYSTEM_ONLY))
1451                 return -EINVAL;
1452
1453         j = journal_new(flags, NULL);
1454         if (!j)
1455                 return -ENOMEM;
1456
1457         r = add_search_paths(j);
1458         if (r < 0)
1459                 goto fail;
1460
1461         *ret = j;
1462         return 0;
1463
1464 fail:
1465         sd_journal_close(j);
1466
1467         return r;
1468 }
1469
1470 _public_ int sd_journal_open_directory(sd_journal **ret, const char *path, int flags) {
1471         sd_journal *j;
1472         int r;
1473
1474         if (!ret)
1475                 return -EINVAL;
1476
1477         if (!path || !path_is_absolute(path))
1478                 return -EINVAL;
1479
1480         if (flags != 0)
1481                 return -EINVAL;
1482
1483         j = journal_new(flags, path);
1484         if (!j)
1485                 return -ENOMEM;
1486
1487         r = add_root_directory(j, path);
1488         if (r < 0)
1489                 goto fail;
1490
1491         *ret = j;
1492         return 0;
1493
1494 fail:
1495         sd_journal_close(j);
1496
1497         return r;
1498 }
1499
1500 _public_ void sd_journal_close(sd_journal *j) {
1501         Directory *d;
1502         JournalFile *f;
1503
1504         if (!j)
1505                 return;
1506
1507         while ((f = hashmap_steal_first(j->files)))
1508                 journal_file_close(f);
1509
1510         hashmap_free(j->files);
1511
1512         while ((d = hashmap_first(j->directories_by_path)))
1513                 remove_directory(j, d);
1514
1515         while ((d = hashmap_first(j->directories_by_wd)))
1516                 remove_directory(j, d);
1517
1518         hashmap_free(j->directories_by_path);
1519         hashmap_free(j->directories_by_wd);
1520
1521         if (j->inotify_fd >= 0)
1522                 close_nointr_nofail(j->inotify_fd);
1523
1524         sd_journal_flush_matches(j);
1525
1526         free(j->path);
1527         free(j);
1528 }
1529
1530 _public_ int sd_journal_get_realtime_usec(sd_journal *j, uint64_t *ret) {
1531         Object *o;
1532         JournalFile *f;
1533         int r;
1534
1535         if (!j)
1536                 return -EINVAL;
1537         if (!ret)
1538                 return -EINVAL;
1539
1540         f = j->current_file;
1541         if (!f)
1542                 return -EADDRNOTAVAIL;
1543
1544         if (f->current_offset <= 0)
1545                 return -EADDRNOTAVAIL;
1546
1547         r = journal_file_move_to_object(f, OBJECT_ENTRY, f->current_offset, &o);
1548         if (r < 0)
1549                 return r;
1550
1551         *ret = le64toh(o->entry.realtime);
1552         return 0;
1553 }
1554
1555 _public_ int sd_journal_get_monotonic_usec(sd_journal *j, uint64_t *ret, sd_id128_t *ret_boot_id) {
1556         Object *o;
1557         JournalFile *f;
1558         int r;
1559         sd_id128_t id;
1560
1561         if (!j)
1562                 return -EINVAL;
1563
1564         f = j->current_file;
1565         if (!f)
1566                 return -EADDRNOTAVAIL;
1567
1568         if (f->current_offset <= 0)
1569                 return -EADDRNOTAVAIL;
1570
1571         r = journal_file_move_to_object(f, OBJECT_ENTRY, f->current_offset, &o);
1572         if (r < 0)
1573                 return r;
1574
1575         if (ret_boot_id)
1576                 *ret_boot_id = o->entry.boot_id;
1577         else {
1578                 r = sd_id128_get_boot(&id);
1579                 if (r < 0)
1580                         return r;
1581
1582                 if (!sd_id128_equal(id, o->entry.boot_id))
1583                         return -ESTALE;
1584         }
1585
1586         if (ret)
1587                 *ret = le64toh(o->entry.monotonic);
1588
1589         return 0;
1590 }
1591
1592 static bool field_is_valid(const char *field) {
1593         const char *p;
1594
1595         assert(field);
1596
1597         if (isempty(field))
1598                 return false;
1599
1600         if (startswith(field, "__"))
1601                 return false;
1602
1603         for (p = field; *p; p++) {
1604
1605                 if (*p == '_')
1606                         continue;
1607
1608                 if (*p >= 'A' && *p <= 'Z')
1609                         continue;
1610
1611                 if (*p >= '0' && *p <= '9')
1612                         continue;
1613
1614                 return false;
1615         }
1616
1617         return true;
1618 }
1619
1620 _public_ int sd_journal_get_data(sd_journal *j, const char *field, const void **data, size_t *size) {
1621         JournalFile *f;
1622         uint64_t i, n;
1623         size_t field_length;
1624         int r;
1625         Object *o;
1626
1627         if (!j)
1628                 return -EINVAL;
1629         if (!field)
1630                 return -EINVAL;
1631         if (!data)
1632                 return -EINVAL;
1633         if (!size)
1634                 return -EINVAL;
1635
1636         if (!field_is_valid(field))
1637                 return -EINVAL;
1638
1639         f = j->current_file;
1640         if (!f)
1641                 return -EADDRNOTAVAIL;
1642
1643         if (f->current_offset <= 0)
1644                 return -EADDRNOTAVAIL;
1645
1646         r = journal_file_move_to_object(f, OBJECT_ENTRY, f->current_offset, &o);
1647         if (r < 0)
1648                 return r;
1649
1650         field_length = strlen(field);
1651
1652         n = journal_file_entry_n_items(o);
1653         for (i = 0; i < n; i++) {
1654                 uint64_t p, l;
1655                 le64_t le_hash;
1656                 size_t t;
1657
1658                 p = le64toh(o->entry.items[i].object_offset);
1659                 le_hash = o->entry.items[i].hash;
1660                 r = journal_file_move_to_object(f, OBJECT_DATA, p, &o);
1661                 if (r < 0)
1662                         return r;
1663
1664                 if (le_hash != o->data.hash)
1665                         return -EBADMSG;
1666
1667                 l = le64toh(o->object.size) - offsetof(Object, data.payload);
1668
1669                 if (o->object.flags & OBJECT_COMPRESSED) {
1670
1671 #ifdef HAVE_XZ
1672                         if (uncompress_startswith(o->data.payload, l,
1673                                                   &f->compress_buffer, &f->compress_buffer_size,
1674                                                   field, field_length, '=')) {
1675
1676                                 uint64_t rsize;
1677
1678                                 if (!uncompress_blob(o->data.payload, l,
1679                                                      &f->compress_buffer, &f->compress_buffer_size, &rsize))
1680                                         return -EBADMSG;
1681
1682                                 *data = f->compress_buffer;
1683                                 *size = (size_t) rsize;
1684
1685                                 return 0;
1686                         }
1687 #else
1688                         return -EPROTONOSUPPORT;
1689 #endif
1690
1691                 } else if (l >= field_length+1 &&
1692                            memcmp(o->data.payload, field, field_length) == 0 &&
1693                            o->data.payload[field_length] == '=') {
1694
1695                         t = (size_t) l;
1696
1697                         if ((uint64_t) t != l)
1698                                 return -E2BIG;
1699
1700                         *data = o->data.payload;
1701                         *size = t;
1702
1703                         return 0;
1704                 }
1705
1706                 r = journal_file_move_to_object(f, OBJECT_ENTRY, f->current_offset, &o);
1707                 if (r < 0)
1708                         return r;
1709         }
1710
1711         return -ENOENT;
1712 }
1713
1714 _public_ int sd_journal_enumerate_data(sd_journal *j, const void **data, size_t *size) {
1715         JournalFile *f;
1716         uint64_t p, l, n;
1717         le64_t le_hash;
1718         int r;
1719         Object *o;
1720         size_t t;
1721
1722         if (!j)
1723                 return -EINVAL;
1724         if (!data)
1725                 return -EINVAL;
1726         if (!size)
1727                 return -EINVAL;
1728
1729         f = j->current_file;
1730         if (!f)
1731                 return -EADDRNOTAVAIL;
1732
1733         if (f->current_offset <= 0)
1734                 return -EADDRNOTAVAIL;
1735
1736         r = journal_file_move_to_object(f, OBJECT_ENTRY, f->current_offset, &o);
1737         if (r < 0)
1738                 return r;
1739
1740         n = journal_file_entry_n_items(o);
1741         if (j->current_field >= n)
1742                 return 0;
1743
1744         p = le64toh(o->entry.items[j->current_field].object_offset);
1745         le_hash = o->entry.items[j->current_field].hash;
1746         r = journal_file_move_to_object(f, OBJECT_DATA, p, &o);
1747         if (r < 0)
1748                 return r;
1749
1750         if (le_hash != o->data.hash)
1751                 return -EBADMSG;
1752
1753         l = le64toh(o->object.size) - offsetof(Object, data.payload);
1754         t = (size_t) l;
1755
1756         /* We can't read objects larger than 4G on a 32bit machine */
1757         if ((uint64_t) t != l)
1758                 return -E2BIG;
1759
1760         if (o->object.flags & OBJECT_COMPRESSED) {
1761 #ifdef HAVE_XZ
1762                 uint64_t rsize;
1763
1764                 if (!uncompress_blob(o->data.payload, l, &f->compress_buffer, &f->compress_buffer_size, &rsize))
1765                         return -EBADMSG;
1766
1767                 *data = f->compress_buffer;
1768                 *size = (size_t) rsize;
1769 #else
1770                 return -EPROTONOSUPPORT;
1771 #endif
1772         } else {
1773                 *data = o->data.payload;
1774                 *size = t;
1775         }
1776
1777         j->current_field ++;
1778
1779         return 1;
1780 }
1781
1782 _public_ void sd_journal_restart_data(sd_journal *j) {
1783         if (!j)
1784                 return;
1785
1786         j->current_field = 0;
1787 }
1788
1789 _public_ int sd_journal_get_fd(sd_journal *j) {
1790         int r;
1791
1792         if (!j)
1793                 return -EINVAL;
1794
1795         if (j->inotify_fd >= 0)
1796                 return j->inotify_fd;
1797
1798         r = allocate_inotify(j);
1799         if (r < 0)
1800                 return r;
1801
1802         /* Iterate through all dirs again, to add them to the
1803          * inotify */
1804         if (j->path)
1805                 r = add_root_directory(j, j->path);
1806         else
1807                 r = add_search_paths(j);
1808         if (r < 0)
1809                 return r;
1810
1811         return j->inotify_fd;
1812 }
1813
1814 static void process_inotify_event(sd_journal *j, struct inotify_event *e) {
1815         Directory *d;
1816         int r;
1817
1818         assert(j);
1819         assert(e);
1820
1821         /* Is this a subdirectory we watch? */
1822         d = hashmap_get(j->directories_by_wd, INT_TO_PTR(e->wd));
1823         if (d) {
1824                 sd_id128_t id;
1825
1826                 if (!(e->mask & IN_ISDIR) && e->len > 0 && endswith(e->name, ".journal")) {
1827
1828                         /* Event for a journal file */
1829
1830                         if (e->mask & (IN_CREATE|IN_MOVED_TO|IN_MODIFY|IN_ATTRIB)) {
1831                                 r = add_file(j, d->path, e->name);
1832                                 if (r < 0)
1833                                         log_debug("Failed to add file %s/%s: %s", d->path, e->name, strerror(-r));
1834
1835                         } else if (e->mask & (IN_DELETE|IN_UNMOUNT)) {
1836
1837                                 r = remove_file(j, d->path, e->name);
1838                                 if (r < 0)
1839                                         log_debug("Failed to remove file %s/%s: %s", d->path, e->name, strerror(-r));
1840                         }
1841
1842                 } else if (!d->is_root && e->len == 0) {
1843
1844                         /* Event for a subdirectory */
1845
1846                         if (e->mask & (IN_DELETE_SELF|IN_MOVE_SELF|IN_UNMOUNT)) {
1847                                 r = remove_directory(j, d);
1848                                 if (r < 0)
1849                                         log_debug("Failed to remove directory %s: %s", d->path, strerror(-r));
1850                         }
1851
1852
1853                 } else if (d->is_root && (e->mask & IN_ISDIR) && e->len > 0 && sd_id128_from_string(e->name, &id) >= 0) {
1854
1855                         /* Event for root directory */
1856
1857                         if (e->mask & (IN_CREATE|IN_MOVED_TO|IN_MODIFY|IN_ATTRIB)) {
1858                                 r = add_directory(j, d->path, e->name);
1859                                 if (r < 0)
1860                                         log_debug("Failed to add directory %s/%s: %s", d->path, e->name, strerror(-r));
1861                         }
1862                 }
1863
1864                 return;
1865         }
1866
1867         if (e->mask & IN_IGNORED)
1868                 return;
1869
1870         log_warning("Unknown inotify event.");
1871 }
1872
1873 static int determine_change(sd_journal *j) {
1874         bool b;
1875
1876         assert(j);
1877
1878         b = j->current_invalidate_counter != j->last_invalidate_counter;
1879         j->last_invalidate_counter = j->current_invalidate_counter;
1880
1881         return b ? SD_JOURNAL_INVALIDATE : SD_JOURNAL_APPEND;
1882 }
1883
1884 _public_ int sd_journal_process(sd_journal *j) {
1885         uint8_t buffer[sizeof(struct inotify_event) + FILENAME_MAX] _alignas_(struct inotify_event);
1886         bool got_something = false;
1887
1888         if (!j)
1889                 return -EINVAL;
1890
1891         for (;;) {
1892                 struct inotify_event *e;
1893                 ssize_t l;
1894
1895                 l = read(j->inotify_fd, buffer, sizeof(buffer));
1896                 if (l < 0) {
1897                         if (errno == EAGAIN || errno == EINTR)
1898                                 return got_something ? determine_change(j) : SD_JOURNAL_NOP;
1899
1900                         return -errno;
1901                 }
1902
1903                 got_something = true;
1904
1905                 e = (struct inotify_event*) buffer;
1906                 while (l > 0) {
1907                         size_t step;
1908
1909                         process_inotify_event(j, e);
1910
1911                         step = sizeof(struct inotify_event) + e->len;
1912                         assert(step <= (size_t) l);
1913
1914                         e = (struct inotify_event*) ((uint8_t*) e + step);
1915                         l -= step;
1916                 }
1917         }
1918
1919         return determine_change(j);
1920 }
1921
1922 _public_ int sd_journal_wait(sd_journal *j, uint64_t timeout_usec) {
1923         int r;
1924
1925         assert(j);
1926
1927         if (j->inotify_fd < 0) {
1928
1929                 /* This is the first invocation, hence create the
1930                  * inotify watch */
1931                 r = sd_journal_get_fd(j);
1932                 if (r < 0)
1933                         return r;
1934
1935                 /* The journal might have changed since the context
1936                  * object was created and we weren't watching before,
1937                  * hence don't wait for anything, and return
1938                  * immediately. */
1939                 return determine_change(j);
1940         }
1941
1942         do {
1943                 r = fd_wait_for_event(j->inotify_fd, POLLIN, timeout_usec);
1944         } while (r == -EINTR);
1945
1946         if (r < 0)
1947                 return r;
1948
1949         return sd_journal_process(j);
1950 }
1951
1952 _public_ int sd_journal_get_cutoff_realtime_usec(sd_journal *j, uint64_t *from, uint64_t *to) {
1953         Iterator i;
1954         JournalFile *f;
1955         bool first = true;
1956         int r;
1957
1958         if (!j)
1959                 return -EINVAL;
1960         if (!from && !to)
1961                 return -EINVAL;
1962
1963         HASHMAP_FOREACH(f, j->files, i) {
1964                 usec_t fr, t;
1965
1966                 r = journal_file_get_cutoff_realtime_usec(f, &fr, &t);
1967                 if (r == -ENOENT)
1968                         continue;
1969                 if (r < 0)
1970                         return r;
1971                 if (r == 0)
1972                         continue;
1973
1974                 if (first) {
1975                         if (from)
1976                                 *from = fr;
1977                         if (to)
1978                                 *to = t;
1979                         first = false;
1980                 } else {
1981                         if (from)
1982                                 *from = MIN(fr, *from);
1983                         if (to)
1984                                 *to = MIN(t, *to);
1985                 }
1986         }
1987
1988         return first ? 0 : 1;
1989 }
1990
1991 _public_ int sd_journal_get_cutoff_monotonic_usec(sd_journal *j, sd_id128_t boot_id, uint64_t *from, uint64_t *to) {
1992         Iterator i;
1993         JournalFile *f;
1994         bool first = true;
1995         int r;
1996
1997         if (!j)
1998                 return -EINVAL;
1999         if (!from && !to)
2000                 return -EINVAL;
2001
2002         HASHMAP_FOREACH(f, j->files, i) {
2003                 usec_t fr, t;
2004
2005                 r = journal_file_get_cutoff_monotonic_usec(f, boot_id, &fr, &t);
2006                 if (r == -ENOENT)
2007                         continue;
2008                 if (r < 0)
2009                         return r;
2010                 if (r == 0)
2011                         continue;
2012
2013                 if (first) {
2014                         if (from)
2015                                 *from = fr;
2016                         if (to)
2017                                 *to = t;
2018                         first = false;
2019                 } else {
2020                         if (from)
2021                                 *from = MIN(fr, *from);
2022                         if (to)
2023                                 *to = MIN(t, *to);
2024                 }
2025         }
2026
2027         return first ? 0 : 1;
2028 }
2029
2030 void journal_print_header(sd_journal *j) {
2031         Iterator i;
2032         JournalFile *f;
2033         bool newline = false;
2034
2035         assert(j);
2036
2037         HASHMAP_FOREACH(f, j->files, i) {
2038                 if (newline)
2039                         putchar('\n');
2040                 else
2041                         newline = true;
2042
2043                 journal_file_print_header(f);
2044         }
2045 }
2046
2047 /* _public_ int sd_journal_query_unique(sd_journal *j, const char *field) { */
2048 /*         if (!j) */
2049 /*                 return -EINVAL; */
2050 /*         if (!field) */
2051 /*                 return -EINVAL; */
2052
2053 /*         return -ENOTSUP; */
2054 /* } */
2055
2056 /* _public_ int sd_journal_enumerate_unique(sd_journal *j, const void **data, size_t *l) { */
2057 /*         if (!j) */
2058 /*                 return -EINVAL; */
2059 /*         if (!data) */
2060 /*                 return -EINVAL; */
2061 /*         if (!l) */
2062 /*                 return -EINVAL; */
2063
2064 /*         return -ENOTSUP; */
2065 /* } */
2066
2067 /* _public_ void sd_journal_restart_unique(sd_journal *j) { */
2068 /*         if (!j) */
2069 /*                 return; */
2070 /* } */