src/journal/journal-file.h

   1 #pragma once
   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 <inttypes.h>
  23
  24 #ifdef HAVE_GCRYPT
  25 #include <gcrypt.h>
  26 #endif
  27
  28 #include "sd-id128.h"
  29
  30 #include "hashmap.h"
  31 #include "journal-def.h"
  32 #include "macro.h"
  33 #include "mmap-cache.h"
  34 #include "sd-event.h"
  35 #include "sparse-endian.h"
  36
  37 typedef struct JournalMetrics {
  38         /* For all these: -1 means "pick automatically", and 0 means "no limit enforced" */
  39         uint64_t max_size;     /* how large journal files grow at max */
  40         uint64_t min_size;     /* how large journal files grow at least */
  41         uint64_t max_use;      /* how much disk space to use in total at max, keep_free permitting */
  42         uint64_t min_use;      /* how much disk space to use in total at least, even if keep_free says not to */
  43         uint64_t keep_free;    /* how much to keep free on disk */
  44         uint64_t n_max_files;  /* how many files to keep around at max */
  45 } JournalMetrics;
  46
  47 typedef enum direction {
  48         DIRECTION_UP,
  49         DIRECTION_DOWN
  50 } direction_t;
  51
  52 typedef enum LocationType {
  53         /* The first and last entries, resp. */
  54         LOCATION_HEAD,
  55         LOCATION_TAIL,
  56
  57         /* We already read the entry we currently point to, and the
  58          * next one to read should probably not be this one again. */
  59         LOCATION_DISCRETE,
  60
  61         /* We should seek to the precise location specified, and
  62          * return it, as we haven't read it yet. */
  63         LOCATION_SEEK
  64 } LocationType;
  65
  66 typedef enum OfflineState {
  67         OFFLINE_JOINED,
  68         OFFLINE_SYNCING,
  69         OFFLINE_OFFLINING,
  70         OFFLINE_CANCEL,
  71         OFFLINE_AGAIN_FROM_SYNCING,
  72         OFFLINE_AGAIN_FROM_OFFLINING,
  73         OFFLINE_DONE
  74 } OfflineState;
  75
  76 typedef struct JournalFile {
  77         int fd;
  78
  79         mode_t mode;
  80
  81         int flags;
  82         int prot;
  83         bool writable:1;
  84         bool compress_xz:1;
  85         bool compress_lz4:1;
  86         bool seal:1;
  87         bool defrag_on_close:1;
  88         bool close_fd:1;
  89         bool archive:1;
  90
  91         bool tail_entry_monotonic_valid:1;
  92
  93         direction_t last_direction;
  94         LocationType location_type;
  95         uint64_t last_n_entries;
  96
  97         char *path;
  98         struct stat last_stat;
  99         usec_t last_stat_usec;
 100
 101         Header *header;
 102         HashItem *data_hash_table;
 103         HashItem *field_hash_table;
 104
 105         uint64_t current_offset;
 106         uint64_t current_seqnum;
 107         uint64_t current_realtime;
 108         uint64_t current_monotonic;
 109         sd_id128_t current_boot_id;
 110         uint64_t current_xor_hash;
 111
 112         JournalMetrics metrics;
 113         MMapCache *mmap;
 114
 115         sd_event_source *post_change_timer;
 116         usec_t post_change_timer_period;
 117
 118         OrderedHashmap *chain_cache;
 119
 120         pthread_t offline_thread;
 121         volatile OfflineState offline_state;
 122
 123 #if defined(HAVE_XZ) || defined(HAVE_LZ4)
 124         void *compress_buffer;
 125         size_t compress_buffer_size;
 126 #endif
 127
 128 #ifdef HAVE_GCRYPT
 129         gcry_md_hd_t hmac;
 130         bool hmac_running;
 131
 132         FSSHeader *fss_file;
 133         size_t fss_file_size;
 134
 135         uint64_t fss_start_usec;
 136         uint64_t fss_interval_usec;
 137
 138         void *fsprg_state;
 139         size_t fsprg_state_size;
 140
 141         void *fsprg_seed;
 142         size_t fsprg_seed_size;
 143 #endif
 144 } JournalFile;
 145
 146 int journal_file_open(
 147                 int fd,
 148                 const char *fname,
 149                 int flags,
 150                 mode_t mode,
 151                 bool compress,
 152                 bool seal,
 153                 JournalMetrics *metrics,
 154                 MMapCache *mmap_cache,
 155                 Set *deferred_closes,
 156                 JournalFile *template,
 157                 JournalFile **ret);
 158
 159 int journal_file_set_offline(JournalFile *f, bool wait);
 160 bool journal_file_is_offlining(JournalFile *f);
 161 JournalFile* journal_file_close(JournalFile *j);
 162 void journal_file_close_set(Set *s);
 163
 164 int journal_file_open_reliably(
 165                 const char *fname,
 166                 int flags,
 167                 mode_t mode,
 168                 bool compress,
 169                 bool seal,
 170                 JournalMetrics *metrics,
 171                 MMapCache *mmap_cache,
 172                 Set *deferred_closes,
 173                 JournalFile *template,
 174                 JournalFile **ret);
 175
 176 #define ALIGN64(x) (((x) + 7ULL) & ~7ULL)
 177 #define VALID64(x) (((x) & 7ULL) == 0ULL)
 178
 179 /* Use six characters to cover the offsets common in smallish journal
 180  * files without adding too many zeros. */
 181 #define OFSfmt "%06"PRIx64
 182
 183 static inline bool VALID_REALTIME(uint64_t u) {
 184         /* This considers timestamps until the year 3112 valid. That should be plenty room... */
 185         return u > 0 && u < (1ULL << 55);
 186 }
 187
 188 static inline bool VALID_MONOTONIC(uint64_t u) {
 189         /* This considers timestamps until 1142 years of runtime valid. */
 190         return u < (1ULL << 55);
 191 }
 192
 193 static inline bool VALID_EPOCH(uint64_t u) {
 194         /* This allows changing the key for 1142 years, every usec. */
 195         return u < (1ULL << 55);
 196 }
 197
 198 #define JOURNAL_HEADER_CONTAINS(h, field) \
 199         (le64toh((h)->header_size) >= offsetof(Header, field) + sizeof((h)->field))
 200
 201 #define JOURNAL_HEADER_SEALED(h) \
 202         (!!(le32toh((h)->compatible_flags) & HEADER_COMPATIBLE_SEALED))
 203
 204 #define JOURNAL_HEADER_COMPRESSED_XZ(h) \
 205         (!!(le32toh((h)->incompatible_flags) & HEADER_INCOMPATIBLE_COMPRESSED_XZ))
 206
 207 #define JOURNAL_HEADER_COMPRESSED_LZ4(h) \
 208         (!!(le32toh((h)->incompatible_flags) & HEADER_INCOMPATIBLE_COMPRESSED_LZ4))
 209
 210 int journal_file_move_to_object(JournalFile *f, ObjectType type, uint64_t offset, Object **ret);
 211
 212 uint64_t journal_file_entry_n_items(Object *o) _pure_;
 213 uint64_t journal_file_entry_array_n_items(Object *o) _pure_;
 214 uint64_t journal_file_hash_table_n_items(Object *o) _pure_;
 215
 216 int journal_file_append_object(JournalFile *f, ObjectType type, uint64_t size, Object **ret, uint64_t *offset);
 217 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);
 218
 219 int journal_file_find_data_object(JournalFile *f, const void *data, uint64_t size, Object **ret, uint64_t *offset);
 220 int journal_file_find_data_object_with_hash(JournalFile *f, const void *data, uint64_t size, uint64_t hash, Object **ret, uint64_t *offset);
 221
 222 int journal_file_find_field_object(JournalFile *f, const void *field, uint64_t size, Object **ret, uint64_t *offset);
 223 int journal_file_find_field_object_with_hash(JournalFile *f, const void *field, uint64_t size, uint64_t hash, Object **ret, uint64_t *offset);
 224
 225 void journal_file_reset_location(JournalFile *f);
 226 void journal_file_save_location(JournalFile *f, Object *o, uint64_t offset);
 227 int journal_file_compare_locations(JournalFile *af, JournalFile *bf);
 228 int journal_file_next_entry(JournalFile *f, uint64_t p, direction_t direction, Object **ret, uint64_t *offset);
 229
 230 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);
 231
 232 int journal_file_move_to_entry_by_seqnum(JournalFile *f, uint64_t seqnum, direction_t direction, Object **ret, uint64_t *offset);
 233 int journal_file_move_to_entry_by_realtime(JournalFile *f, uint64_t realtime, direction_t direction, Object **ret, uint64_t *offset);
 234 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);
 235
 236 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);
 237 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);
 238 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);
 239 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);
 240
 241 int journal_file_copy_entry(JournalFile *from, JournalFile *to, Object *o, uint64_t p, uint64_t *seqnum, Object **ret, uint64_t *offset);
 242
 243 void journal_file_dump(JournalFile *f);
 244 void journal_file_print_header(JournalFile *f);
 245
 246 int journal_file_rotate(JournalFile **f, bool compress, bool seal, Set *deferred_closes);
 247
 248 void journal_file_post_change(JournalFile *f);
 249 int journal_file_enable_post_change_timer(JournalFile *f, sd_event *e, usec_t t);
 250
 251 void journal_reset_metrics(JournalMetrics *m);
 252 void journal_default_metrics(JournalMetrics *m, int fd);
 253
 254 int journal_file_get_cutoff_realtime_usec(JournalFile *f, usec_t *from, usec_t *to);
 255 int journal_file_get_cutoff_monotonic_usec(JournalFile *f, sd_id128_t boot, usec_t *from, usec_t *to);
 256
 257 bool journal_file_rotate_suggested(JournalFile *f, usec_t max_file_usec);
 258
 259 int journal_file_map_data_hash_table(JournalFile *f);
 260 int journal_file_map_field_hash_table(JournalFile *f);
 261
 262 static inline bool JOURNAL_FILE_COMPRESS(JournalFile *f) {
 263         assert(f);
 264         return f->compress_xz || f->compress_lz4;
 265 }