chiark / gitweb /
journal: fix iteration when we go backwards from the beginning of an array chain...
[elogind.git] / src / journal / journal-file.h
1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
2
3 #pragma once
4
5 /***
6   This file is part of systemd.
7
8   Copyright 2011 Lennart Poettering
9
10   systemd is free software; you can redistribute it and/or modify it
11   under the terms of the GNU Lesser General Public License as published by
12   the Free Software Foundation; either version 2.1 of the License, or
13   (at your option) any later version.
14
15   systemd is distributed in the hope that it will be useful, but
16   WITHOUT ANY WARRANTY; without even the implied warranty of
17   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18   Lesser General Public License for more details.
19
20   You should have received a copy of the GNU Lesser General Public License
21   along with systemd; If not, see <http://www.gnu.org/licenses/>.
22 ***/
23
24 #include <inttypes.h>
25
26 #ifdef HAVE_GCRYPT
27 #include <gcrypt.h>
28 #endif
29
30 #include <systemd/sd-id128.h>
31
32 #include "sparse-endian.h"
33 #include "journal-def.h"
34 #include "util.h"
35 #include "mmap-cache.h"
36 #include "hashmap.h"
37
38 typedef struct JournalMetrics {
39         uint64_t max_use;
40         uint64_t max_size;
41         uint64_t min_size;
42         uint64_t keep_free;
43 } JournalMetrics;
44
45 typedef enum direction {
46         DIRECTION_UP,
47         DIRECTION_DOWN
48 } direction_t;
49
50 typedef struct JournalFile {
51         int fd;
52
53         mode_t mode;
54
55         int flags;
56         int prot;
57         bool writable:1;
58         bool compress:1;
59         bool seal:1;
60
61         bool tail_entry_monotonic_valid:1;
62
63         direction_t last_direction;
64
65         char *path;
66         struct stat last_stat;
67
68         Header *header;
69         HashItem *data_hash_table;
70         HashItem *field_hash_table;
71
72         uint64_t current_offset;
73
74         JournalMetrics metrics;
75         MMapCache *mmap;
76
77         Hashmap *chain_cache;
78
79 #ifdef HAVE_XZ
80         void *compress_buffer;
81         uint64_t compress_buffer_size;
82 #endif
83
84 #ifdef HAVE_GCRYPT
85         gcry_md_hd_t hmac;
86         bool hmac_running;
87
88         FSSHeader *fss_file;
89         size_t fss_file_size;
90
91         uint64_t fss_start_usec;
92         uint64_t fss_interval_usec;
93
94         void *fsprg_state;
95         size_t fsprg_state_size;
96
97         void *fsprg_seed;
98         size_t fsprg_seed_size;
99 #endif
100 } JournalFile;
101
102 int journal_file_open(
103                 const char *fname,
104                 int flags,
105                 mode_t mode,
106                 bool compress,
107                 bool seal,
108                 JournalMetrics *metrics,
109                 MMapCache *mmap_cache,
110                 JournalFile *template,
111                 JournalFile **ret);
112
113 int journal_file_set_offline(JournalFile *f);
114 void journal_file_close(JournalFile *j);
115
116 int journal_file_open_reliably(
117                 const char *fname,
118                 int flags,
119                 mode_t mode,
120                 bool compress,
121                 bool seal,
122                 JournalMetrics *metrics,
123                 MMapCache *mmap_cache,
124                 JournalFile *template,
125                 JournalFile **ret);
126
127 #define ALIGN64(x) (((x) + 7ULL) & ~7ULL)
128 #define VALID64(x) (((x) & 7ULL) == 0ULL)
129
130 static inline bool VALID_REALTIME(uint64_t u) {
131         /* This considers timestamps until the year 3112 valid. That should be plenty room... */
132         return u > 0 && u < (1ULL << 55);
133 }
134
135 static inline bool VALID_MONOTONIC(uint64_t u) {
136         /* This considers timestamps until 1142 years of runtime valid. */
137         return u < (1ULL << 55);
138 }
139
140 static inline bool VALID_EPOCH(uint64_t u) {
141         /* This allows changing the key for 1142 years, every usec. */
142         return u < (1ULL << 55);
143 }
144
145 #define JOURNAL_HEADER_CONTAINS(h, field) \
146         (le64toh((h)->header_size) >= offsetof(Header, field) + sizeof((h)->field))
147
148 #define JOURNAL_HEADER_SEALED(h) \
149         (!!(le32toh((h)->compatible_flags) & HEADER_COMPATIBLE_SEALED))
150
151 #define JOURNAL_HEADER_COMPRESSED(h) \
152         (!!(le32toh((h)->incompatible_flags) & HEADER_INCOMPATIBLE_COMPRESSED))
153
154 int journal_file_move_to_object(JournalFile *f, int type, uint64_t offset, Object **ret);
155
156 uint64_t journal_file_entry_n_items(Object *o) _pure_;
157 uint64_t journal_file_entry_array_n_items(Object *o) _pure_;
158 uint64_t journal_file_hash_table_n_items(Object *o) _pure_;
159
160 int journal_file_append_object(JournalFile *f, int type, uint64_t size, Object **ret, uint64_t *offset);
161 int journal_file_append_entry(JournalFile *f, const dual_timestamp *ts, const struct iovec iovec[], unsigned n_iovec, uint64_t *seqno, Object **ret, uint64_t *offset);
162
163 int journal_file_find_data_object(JournalFile *f, const void *data, uint64_t size, Object **ret, uint64_t *offset);
164 int journal_file_find_data_object_with_hash(JournalFile *f, const void *data, uint64_t size, uint64_t hash, Object **ret, uint64_t *offset);
165
166 int journal_file_find_field_object(JournalFile *f, const void *field, uint64_t size, Object **ret, uint64_t *offset);
167 int journal_file_find_field_object_with_hash(JournalFile *f, const void *field, uint64_t size, uint64_t hash, Object **ret, uint64_t *offset);
168
169 int journal_file_next_entry(JournalFile *f, Object *o, uint64_t p, direction_t direction, Object **ret, uint64_t *offset);
170 int journal_file_skip_entry(JournalFile *f, Object *o, uint64_t p, int64_t skip, Object **ret, uint64_t *offset);
171
172 int journal_file_next_entry_for_data(JournalFile *f, Object *o, uint64_t p, uint64_t data_offset, direction_t direction, Object **ret, uint64_t *offset);
173
174 int journal_file_move_to_entry_by_offset(JournalFile *f, uint64_t seqnum, direction_t direction, Object **ret, uint64_t *offset);
175 int journal_file_move_to_entry_by_seqnum(JournalFile *f, uint64_t seqnum, direction_t direction, Object **ret, uint64_t *offset);
176 int journal_file_move_to_entry_by_realtime(JournalFile *f, uint64_t realtime, direction_t direction, Object **ret, uint64_t *offset);
177 int journal_file_move_to_entry_by_monotonic(JournalFile *f, sd_id128_t boot_id, uint64_t monotonic, direction_t direction, Object **ret, uint64_t *offset);
178
179 int journal_file_move_to_entry_by_offset_for_data(JournalFile *f, uint64_t data_offset, uint64_t p, direction_t direction, Object **ret, uint64_t *offset);
180 int journal_file_move_to_entry_by_seqnum_for_data(JournalFile *f, uint64_t data_offset, uint64_t seqnum, direction_t direction, Object **ret, uint64_t *offset);
181 int journal_file_move_to_entry_by_realtime_for_data(JournalFile *f, uint64_t data_offset, uint64_t realtime, direction_t direction, Object **ret, uint64_t *offset);
182 int journal_file_move_to_entry_by_monotonic_for_data(JournalFile *f, uint64_t data_offset, sd_id128_t boot_id, uint64_t monotonic, direction_t direction, Object **ret, uint64_t *offset);
183
184 int journal_file_copy_entry(JournalFile *from, JournalFile *to, Object *o, uint64_t p, uint64_t *seqnum, Object **ret, uint64_t *offset);
185
186 void journal_file_dump(JournalFile *f);
187 void journal_file_print_header(JournalFile *f);
188
189 int journal_file_rotate(JournalFile **f, bool compress, bool seal);
190
191 void journal_file_post_change(JournalFile *f);
192
193 void journal_default_metrics(JournalMetrics *m, int fd);
194
195 int journal_file_get_cutoff_realtime_usec(JournalFile *f, usec_t *from, usec_t *to);
196 int journal_file_get_cutoff_monotonic_usec(JournalFile *f, sd_id128_t boot, usec_t *from, usec_t *to);
197
198 bool journal_file_rotate_suggested(JournalFile *f, usec_t max_file_usec);