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