Systemd/src/journal/journald-server.h
Lennart Poettering d3070fbdf6 core: implement /run/systemd/units/-based path for passing unit info from PID 1 to journald
And let's make use of it to implement two new unit settings with it:

1. LogLevelMax= is a new per-unit setting that may be used to configure
   log priority filtering: set it to LogLevelMax=notice and only
   messages of level "notice" and lower (i.e. more important) will be
   processed, all others are dropped.

2. LogExtraFields= is a new per-unit setting for configuring per-unit
   journal fields, that are implicitly included in every log record
   generated by the unit's processes. It takes field/value pairs in the
   form of FOO=BAR.

Also, related to this, one exisiting unit setting is ported to this new
facility:

3. The invocation ID is now pulled from /run/systemd/units/ instead of
   cgroupfs xattrs. This substantially relaxes requirements of systemd
   on the kernel version and the privileges it runs with (specifically,
   cgroupfs xattrs are not available in containers, since they are
   stored in kernel memory, and hence are unsafe to permit to lesser
   privileged code).

/run/systemd/units/ is a new directory, which contains a number of files
and symlinks encoding the above information. PID 1 creates and manages
these files, and journald reads them from there.

Note that this is supposed to be a direct path between PID 1 and the
journal only, due to the special runtime environment the journal runs
in. Normally, today we shouldn't introduce new interfaces that (mis-)use
a file system as IPC framework, and instead just an IPC system, but this
is very hard to do between the journal and PID 1, as long as the IPC
system is a subject PID 1 manages, and itself a client to the journal.

This patch cleans up a couple of types used in journal code:
specifically we switch to size_t for a couple of memory-sizing values,
as size_t is the right choice for everything that is memory.

Fixes: #4089
Fixes: #3041
Fixes: #4441
2017-11-16 12:40:17 +01:00

217 lines
6.5 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-context.h"
#include "journald-rate-limit.h"
#include "journald-stream.h"
#include "list.h"
#include "prioq.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, /* deprecated */
SPLIT_NONE,
_SPLIT_MAX,
_SPLIT_INVALID = -1
} SplitMode;
typedef struct JournalStorageSpace {
usec_t timestamp;
uint64_t available;
uint64_t limit;
uint64_t vfs_used; /* space used by journal files */
uint64_t vfs_available;
} JournalStorageSpace;
typedef struct JournalStorage {
const char *name;
char *path;
JournalMetrics metrics;
JournalStorageSpace space;
} JournalStorage;
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;
JournalStorage runtime_storage;
JournalStorage system_storage;
bool compress;
bool seal;
bool read_kmsg;
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 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;
usec_t last_realtime_clock;
size_t line_max;
/* Caching of client metadata */
Hashmap *client_contexts;
Prioq *client_contexts_lru;
ClientContext *my_context; /* the context of journald itself */
ClientContext *pid1_context; /* the context of PID 1 */
};
#define SERVER_MACHINE_ID(s) ((s)->machine_id_field + strlen("_MACHINE_ID="))
#define N_IOVEC_META_FIELDS 22
#define N_IOVEC_KERNEL_FIELDS 64
#define N_IOVEC_UDEV_FIELDS 32
#define N_IOVEC_OBJECT_FIELDS 14
#define N_IOVEC_PAYLOAD_FIELDS 15
void server_dispatch_message(Server *s, struct iovec *iovec, size_t n, size_t m, ClientContext *c, const struct timeval *tv, int priority, pid_t object_pid);
void server_driver_message(Server *s, pid_t object_pid, const char *message_id, const char *format, ...) _sentinel_;
/* gperf lookup function */
const struct ConfigPerfItem* journald_gperf_lookup(const char *key, GPERF_LEN_TYPE 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);
int config_parse_line_max(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);
void server_rotate(Server *s);
int server_schedule_sync(Server *s, int priority);
int server_flush_to_var(Server *s, bool require_flag_file);
void server_maybe_append_tags(Server *s);
int server_process_datagram(sd_event_source *es, int fd, uint32_t revents, void *userdata);
void server_space_usage_message(Server *s, JournalStorage *storage);