Systemd/src/journal/journald-server.h
Vito Caputo b58c888f30 journal: defer journal closes on rotate
When we rotate journals, we must set offline and close the current one,
but don't generally need to wait for this to complete.

Instead, we'll initiate an asynchronous offline via
journal_file_set_offline(oldfile, false), and add the file to a
per-server set of deferred closes to be closed later when they
won't block.

There's one complication however; journal_file_open() via
journal_file_verify_header() assumes that any writable journal in the
online state is the product of an unclean shutdown or other form of
corruption.

Thus there's a need for journal_file_open() to be aware of deferred
closes and synchronize with their completion when opening preexisting
journals for writing.  To facilitate this the deferred closes set is
supplied to the journal_file_open() function where the deferred closes
may be closed synchronously before verifying the header in such
circumstances.
2016-02-19 18:50:20 -08:00

187 lines
5.6 KiB
C

#pragma once
/***
This file is part of systemd.
Copyright 2011 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <stdbool.h>
#include <sys/types.h>
#include "sd-event.h"
typedef struct Server Server;
#include "hashmap.h"
#include "journal-file.h"
#include "journald-rate-limit.h"
#include "journald-stream.h"
#include "list.h"
typedef enum Storage {
STORAGE_AUTO,
STORAGE_VOLATILE,
STORAGE_PERSISTENT,
STORAGE_NONE,
_STORAGE_MAX,
_STORAGE_INVALID = -1
} Storage;
typedef enum SplitMode {
SPLIT_UID,
SPLIT_LOGIN,
SPLIT_NONE,
_SPLIT_MAX,
_SPLIT_INVALID = -1
} SplitMode;
struct Server {
int syslog_fd;
int native_fd;
int stdout_fd;
int dev_kmsg_fd;
int audit_fd;
int hostname_fd;
int notify_fd;
sd_event *event;
sd_event_source *syslog_event_source;
sd_event_source *native_event_source;
sd_event_source *stdout_event_source;
sd_event_source *dev_kmsg_event_source;
sd_event_source *audit_event_source;
sd_event_source *sync_event_source;
sd_event_source *sigusr1_event_source;
sd_event_source *sigusr2_event_source;
sd_event_source *sigterm_event_source;
sd_event_source *sigint_event_source;
sd_event_source *sigrtmin1_event_source;
sd_event_source *hostname_event_source;
sd_event_source *notify_event_source;
sd_event_source *watchdog_event_source;
JournalFile *runtime_journal;
JournalFile *system_journal;
OrderedHashmap *user_journals;
uint64_t seqnum;
char *buffer;
size_t buffer_size;
JournalRateLimit *rate_limit;
usec_t sync_interval_usec;
usec_t rate_limit_interval;
unsigned rate_limit_burst;
JournalMetrics runtime_metrics;
JournalMetrics system_metrics;
bool compress;
bool seal;
bool forward_to_kmsg;
bool forward_to_syslog;
bool forward_to_console;
bool forward_to_wall;
unsigned n_forward_syslog_missed;
usec_t last_warn_forward_syslog_missed;
uint64_t cached_space_available;
uint64_t cached_space_limit;
usec_t cached_space_timestamp;
uint64_t var_available_timestamp;
usec_t max_retention_usec;
usec_t max_file_usec;
usec_t oldest_file_usec;
LIST_HEAD(StdoutStream, stdout_streams);
LIST_HEAD(StdoutStream, stdout_streams_notify_queue);
unsigned n_stdout_streams;
char *tty_path;
int max_level_store;
int max_level_syslog;
int max_level_kmsg;
int max_level_console;
int max_level_wall;
Storage storage;
SplitMode split_mode;
MMapCache *mmap;
Set *deferred_closes;
struct udev *udev;
uint64_t *kernel_seqnum;
bool dev_kmsg_readable:1;
bool send_watchdog:1;
bool sent_notify_ready:1;
bool sync_scheduled:1;
char machine_id_field[sizeof("_MACHINE_ID=") + 32];
char boot_id_field[sizeof("_BOOT_ID=") + 32];
char *hostname_field;
/* Cached cgroup root, so that we don't have to query that all the time */
char *cgroup_root;
usec_t watchdog_usec;
};
#define SERVER_MACHINE_ID(s) ((s)->machine_id_field + strlen("_MACHINE_ID="))
#define N_IOVEC_META_FIELDS 20
#define N_IOVEC_KERNEL_FIELDS 64
#define N_IOVEC_UDEV_FIELDS 32
#define N_IOVEC_OBJECT_FIELDS 12
#define N_IOVEC_PAYLOAD_FIELDS 15
void server_dispatch_message(Server *s, struct iovec *iovec, unsigned n, unsigned m, const struct ucred *ucred, const struct timeval *tv, const char *label, size_t label_len, const char *unit_id, int priority, pid_t object_pid);
void server_driver_message(Server *s, sd_id128_t message_id, const char *format, ...) _printf_(3,0) _sentinel_;
/* gperf lookup function */
const struct ConfigPerfItem* journald_gperf_lookup(const char *key, unsigned length);
int config_parse_storage(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
const char *storage_to_string(Storage s) _const_;
Storage storage_from_string(const char *s) _pure_;
int config_parse_split_mode(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
const char *split_mode_to_string(SplitMode s) _const_;
SplitMode split_mode_from_string(const char *s) _pure_;
int server_init(Server *s);
void server_done(Server *s);
void server_sync(Server *s);
int server_vacuum(Server *s, bool verbose, bool patch_min_use);
void server_rotate(Server *s);
int server_schedule_sync(Server *s, int priority);
int server_flush_to_var(Server *s);
void server_maybe_append_tags(Server *s);
int server_process_datagram(sd_event_source *es, int fd, uint32_t revents, void *userdata);