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
  90         bool tail_entry_monotonic_valid:1;
  91
  92         direction_t last_direction;
  93         LocationType location_type;
  94         uint64_t last_n_entries;
  95
  96         char *path;
  97         struct stat last_stat;
  98         usec_t last_stat_usec;
  99
 100         Header *header;
 101         HashItem *data_hash_table;
 102         HashItem *field_hash_table;
 103
 104         uint64_t current_offset;
 105         uint64_t current_seqnum;
 106         uint64_t current_realtime;
 107         uint64_t current_monotonic;
 108         sd_id128_t current_boot_id;
 109         uint64_t current_xor_hash;
 110
 111         JournalMetrics metrics;
 112         MMapCache *mmap;
 113
 114         sd_event_source *post_change_timer;
 115         usec_t post_change_timer_period;
 116
 117         OrderedHashmap *chain_cache;
 118
 119         pthread_t offline_thread;
 120         volatile OfflineState offline_state;
 121
 122 #if defined(HAVE_XZ) || defined(HAVE_LZ4)
 123         void *compress_buffer;
 124         size_t compress_buffer_size;
 125 #endif
 126
 127 #ifdef HAVE_GCRYPT
 128         gcry_md_hd_t hmac;
 129         bool hmac_running;
 130
 131         FSSHeader *fss_file;
 132         size_t fss_file_size;
 133
 134         uint64_t fss_start_usec;
 135         uint64_t fss_interval_usec;
 136
 137         void *fsprg_state;
 138         size_t fsprg_state_size;
 139
 140         void *fsprg_seed;
 141         size_t fsprg_seed_size;
 142 #endif
 143 } JournalFile;
 144
 145 int journal_file_open(
 146                 int fd,
 147                 const char *fname,
 148                 int flags,
 149                 mode_t mode,
 150                 bool compress,
 151                 bool seal,
 152                 JournalMetrics *metrics,
 153                 MMapCache *mmap_cache,
 154                 Set *deferred_closes,
 155                 JournalFile *template,
 156                 JournalFile **ret);
 157
 158 int journal_file_set_offline(JournalFile *f, bool wait);
 159 bool journal_file_is_offlining(JournalFile *f);
 160 JournalFile* journal_file_close(JournalFile *j);
 161 void journal_file_close_set(Set *s);
 162
 163 int journal_file_open_reliably(
 164                 const char *fname,
 165                 int flags,
 166                 mode_t mode,
 167                 bool compress,
 168                 bool seal,
 169                 JournalMetrics *metrics,
 170                 MMapCache *mmap_cache,
 171                 Set *deferred_closes,
 172                 JournalFile *template,
 173                 JournalFile **ret);
 174
 175 #define ALIGN64(x) (((x) + 7ULL) & ~7ULL)
 176 #define VALID64(x) (((x) & 7ULL) == 0ULL)
 177
 178 /* Use six characters to cover the offsets common in smallish journal
 179  * files without adding too many zeros. */
 180 #define OFSfmt "%06"PRIx64
 181
 182 static inline bool VALID_REALTIME(uint64_t u) {
 183         /* This considers timestamps until the year 3112 valid. That should be plenty room... */
 184         return u > 0 && u < (1ULL << 55);
 185 }
 186
 187 static inline bool VALID_MONOTONIC(uint64_t u) {
 188         /* This considers timestamps until 1142 years of runtime valid. */
 189         return u < (1ULL << 55);
 190 }
 191
 192 static inline bool VALID_EPOCH(uint64_t u) {
 193         /* This allows changing the key for 1142 years, every usec. */
 194         return u < (1ULL << 55);
 195 }
 196
 197 #define JOURNAL_HEADER_CONTAINS(h, field) \
 198         (le64toh((h)->header_size) >= offsetof(Header, field) + sizeof((h)->field))
 199
 200 #define JOURNAL_HEADER_SEALED(h) \
 201         (!!(le32toh((h)->compatible_flags) & HEADER_COMPATIBLE_SEALED))
 202
 203 #define JOURNAL_HEADER_COMPRESSED_XZ(h) \
 204         (!!(le32toh((h)->incompatible_flags) & HEADER_INCOMPATIBLE_COMPRESSED_XZ))
 205
 206 #define JOURNAL_HEADER_COMPRESSED_LZ4(h) \
 207         (!!(le32toh((h)->incompatible_flags) & HEADER_INCOMPATIBLE_COMPRESSED_LZ4))
 208
 209 int journal_file_move_to_object(JournalFile *f, ObjectType type, uint64_t offset, Object **ret);
 210
 211 uint64_t journal_file_entry_n_items(Object *o) _pure_;
 212 uint64_t journal_file_entry_array_n_items(Object *o) _pure_;
 213 uint64_t journal_file_hash_table_n_items(Object *o) _pure_;
 214
 215 int journal_file_append_object(JournalFile *f, ObjectType type, uint64_t size, Object **ret, uint64_t *offset);
 216 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);
 217
 218 int journal_file_find_data_object(JournalFile *f, const void *data, uint64_t size, Object **ret, uint64_t *offset);
 219 int journal_file_find_data_object_with_hash(JournalFile *f, const void *data, uint64_t size, uint64_t hash, Object **ret, uint64_t *offset);
 220
 221 int journal_file_find_field_object(JournalFile *f, const void *field, uint64_t size, Object **ret, uint64_t *offset);
 222 int journal_file_find_field_object_with_hash(JournalFile *f, const void *field, uint64_t size, uint64_t hash, Object **ret, uint64_t *offset);
 223
 224 void journal_file_reset_location(JournalFile *f);
 225 void journal_file_save_location(JournalFile *f, Object *o, uint64_t offset);
 226 int journal_file_compare_locations(JournalFile *af, JournalFile *bf);
 227 int journal_file_next_entry(JournalFile *f, uint64_t p, direction_t direction, Object **ret, uint64_t *offset);
 228
 229 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);
 230
 231 int journal_file_move_to_entry_by_seqnum(JournalFile *f, uint64_t seqnum, direction_t direction, Object **ret, uint64_t *offset);
 232 int journal_file_move_to_entry_by_realtime(JournalFile *f, uint64_t realtime, direction_t direction, Object **ret, uint64_t *offset);
 233 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);
 234
 235 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);
 236 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);
 237 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);
 238 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);
 239
 240 int journal_file_copy_entry(JournalFile *from, JournalFile *to, Object *o, uint64_t p, uint64_t *seqnum, Object **ret, uint64_t *offset);
 241
 242 void journal_file_dump(JournalFile *f);
 243 void journal_file_print_header(JournalFile *f);
 244
 245 int journal_file_rotate(JournalFile **f, bool compress, bool seal, Set *deferred_closes);
 246
 247 void journal_file_post_change(JournalFile *f);
 248 int journal_file_enable_post_change_timer(JournalFile *f, sd_event *e, usec_t t);
 249
 250 void journal_reset_metrics(JournalMetrics *m);
 251 void journal_default_metrics(JournalMetrics *m, int fd);
 252
 253 int journal_file_get_cutoff_realtime_usec(JournalFile *f, usec_t *from, usec_t *to);
 254 int journal_file_get_cutoff_monotonic_usec(JournalFile *f, sd_id128_t boot, usec_t *from, usec_t *to);
 255
 256 bool journal_file_rotate_suggested(JournalFile *f, usec_t max_file_usec);
 257
 258 int journal_file_map_data_hash_table(JournalFile *f);
 259 int journal_file_map_field_hash_table(JournalFile *f);
 260
 261 static inline bool JOURNAL_FILE_COMPRESS(JournalFile *f) {
 262         assert(f);
 263         return f->compress_xz || f->compress_lz4;
 264 }