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         MMapFileDescriptor *cache_fd;
  79
  80         mode_t mode;
  81
  82         int flags;
  83         int prot;
  84         bool writable:1;
  85         bool compress_xz:1;
  86         bool compress_lz4:1;
  87         bool seal:1;
  88         bool defrag_on_close:1;
  89         bool close_fd:1;
  90         bool archive:1;
  91
  92         bool tail_entry_monotonic_valid:1;
  93
  94         direction_t last_direction;
  95         LocationType location_type;
  96         uint64_t last_n_entries;
  97
  98         char *path;
  99         struct stat last_stat;
 100         usec_t last_stat_usec;
 101
 102         Header *header;
 103         HashItem *data_hash_table;
 104         HashItem *field_hash_table;
 105
 106         uint64_t current_offset;
 107         uint64_t current_seqnum;
 108         uint64_t current_realtime;
 109         uint64_t current_monotonic;
 110         sd_id128_t current_boot_id;
 111         uint64_t current_xor_hash;
 112
 113         JournalMetrics metrics;
 114         MMapCache *mmap;
 115
 116         sd_event_source *post_change_timer;
 117         usec_t post_change_timer_period;
 118
 119         OrderedHashmap *chain_cache;
 120
 121         pthread_t offline_thread;
 122         volatile OfflineState offline_state;
 123
 124 #if defined(HAVE_XZ) || defined(HAVE_LZ4)
 125         void *compress_buffer;
 126         size_t compress_buffer_size;
 127 #endif
 128
 129 #ifdef HAVE_GCRYPT
 130         gcry_md_hd_t hmac;
 131         bool hmac_running;
 132
 133         FSSHeader *fss_file;
 134         size_t fss_file_size;
 135
 136         uint64_t fss_start_usec;
 137         uint64_t fss_interval_usec;
 138
 139         void *fsprg_state;
 140         size_t fsprg_state_size;
 141
 142         void *fsprg_seed;
 143         size_t fsprg_seed_size;
 144 #endif
 145 } JournalFile;
 146
 147 int journal_file_open(
 148                 int fd,
 149                 const char *fname,
 150                 int flags,
 151                 mode_t mode,
 152                 bool compress,
 153                 bool seal,
 154                 JournalMetrics *metrics,
 155                 MMapCache *mmap_cache,
 156                 Set *deferred_closes,
 157                 JournalFile *template,
 158                 JournalFile **ret);
 159
 160 int journal_file_set_offline(JournalFile *f, bool wait);
 161 bool journal_file_is_offlining(JournalFile *f);
 162 JournalFile* journal_file_close(JournalFile *j);
 163 void journal_file_close_set(Set *s);
 164
 165 int journal_file_open_reliably(
 166                 const char *fname,
 167                 int flags,
 168                 mode_t mode,
 169                 bool compress,
 170                 bool seal,
 171                 JournalMetrics *metrics,
 172                 MMapCache *mmap_cache,
 173                 Set *deferred_closes,
 174                 JournalFile *template,
 175                 JournalFile **ret);
 176
 177 #define ALIGN64(x) (((x) + 7ULL) & ~7ULL)
 178 #define VALID64(x) (((x) & 7ULL) == 0ULL)
 179
 180 /* Use six characters to cover the offsets common in smallish journal
 181  * files without adding too many zeros. */
 182 #define OFSfmt "%06"PRIx64
 183
 184 static inline bool VALID_REALTIME(uint64_t u) {
 185         /* This considers timestamps until the year 3112 valid. That should be plenty room... */
 186         return u > 0 && u < (1ULL << 55);
 187 }
 188
 189 static inline bool VALID_MONOTONIC(uint64_t u) {
 190         /* This considers timestamps until 1142 years of runtime valid. */
 191         return u < (1ULL << 55);
 192 }
 193
 194 static inline bool VALID_EPOCH(uint64_t u) {
 195         /* This allows changing the key for 1142 years, every usec. */
 196         return u < (1ULL << 55);
 197 }
 198
 199 #define JOURNAL_HEADER_CONTAINS(h, field) \
 200         (le64toh((h)->header_size) >= offsetof(Header, field) + sizeof((h)->field))
 201
 202 #define JOURNAL_HEADER_SEALED(h) \
 203         (!!(le32toh((h)->compatible_flags) & HEADER_COMPATIBLE_SEALED))
 204
 205 #define JOURNAL_HEADER_COMPRESSED_XZ(h) \
 206         (!!(le32toh((h)->incompatible_flags) & HEADER_INCOMPATIBLE_COMPRESSED_XZ))
 207
 208 #define JOURNAL_HEADER_COMPRESSED_LZ4(h) \
 209         (!!(le32toh((h)->incompatible_flags) & HEADER_INCOMPATIBLE_COMPRESSED_LZ4))
 210
 211 int journal_file_move_to_object(JournalFile *f, ObjectType type, uint64_t offset, Object **ret);
 212
 213 uint64_t journal_file_entry_n_items(Object *o) _pure_;
 214 uint64_t journal_file_entry_array_n_items(Object *o) _pure_;
 215 uint64_t journal_file_hash_table_n_items(Object *o) _pure_;
 216
 217 int journal_file_append_object(JournalFile *f, ObjectType type, uint64_t size, Object **ret, uint64_t *offset);
 218 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);
 219
 220 int journal_file_find_data_object(JournalFile *f, const void *data, uint64_t size, Object **ret, uint64_t *offset);
 221 int journal_file_find_data_object_with_hash(JournalFile *f, const void *data, uint64_t size, uint64_t hash, Object **ret, uint64_t *offset);
 222
 223 int journal_file_find_field_object(JournalFile *f, const void *field, uint64_t size, Object **ret, uint64_t *offset);
 224 int journal_file_find_field_object_with_hash(JournalFile *f, const void *field, uint64_t size, uint64_t hash, Object **ret, uint64_t *offset);
 225
 226 void journal_file_reset_location(JournalFile *f);
 227 void journal_file_save_location(JournalFile *f, Object *o, uint64_t offset);
 228 int journal_file_compare_locations(JournalFile *af, JournalFile *bf);
 229 int journal_file_next_entry(JournalFile *f, uint64_t p, direction_t direction, Object **ret, uint64_t *offset);
 230
 231 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);
 232
 233 int journal_file_move_to_entry_by_seqnum(JournalFile *f, uint64_t seqnum, direction_t direction, Object **ret, uint64_t *offset);
 234 int journal_file_move_to_entry_by_realtime(JournalFile *f, uint64_t realtime, direction_t direction, Object **ret, uint64_t *offset);
 235 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);
 236
 237 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);
 238 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);
 239 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);
 240 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);
 241
 242 int journal_file_copy_entry(JournalFile *from, JournalFile *to, Object *o, uint64_t p, uint64_t *seqnum, Object **ret, uint64_t *offset);
 243
 244 void journal_file_dump(JournalFile *f);
 245 void journal_file_print_header(JournalFile *f);
 246
 247 int journal_file_rotate(JournalFile **f, bool compress, bool seal, Set *deferred_closes);
 248
 249 void journal_file_post_change(JournalFile *f);
 250 int journal_file_enable_post_change_timer(JournalFile *f, sd_event *e, usec_t t);
 251
 252 void journal_reset_metrics(JournalMetrics *m);
 253 void journal_default_metrics(JournalMetrics *m, int fd);
 254
 255 int journal_file_get_cutoff_realtime_usec(JournalFile *f, usec_t *from, usec_t *to);
 256 int journal_file_get_cutoff_monotonic_usec(JournalFile *f, sd_id128_t boot, usec_t *from, usec_t *to);
 257
 258 bool journal_file_rotate_suggested(JournalFile *f, usec_t max_file_usec);
 259
 260 int journal_file_map_data_hash_table(JournalFile *f);
 261 int journal_file_map_field_hash_table(JournalFile *f);
 262
 263 static inline bool JOURNAL_FILE_COMPRESS(JournalFile *f) {
 264         assert(f);
 265         return f->compress_xz || f->compress_lz4;
 266 }