src/core/manager.h

/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/

#pragma once

/***
  This file is part of systemd.

  Copyright 2010 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 <inttypes.h>
#include <stdio.h>

#include "sd-bus.h"
#include "sd-event.h"
#include "fdset.h"
#include "cgroup-util.h"

/* Enforce upper limit how many names we allow */
#define MANAGER_MAX_NAMES 131072 /* 128K */

typedef struct Manager Manager;

typedef enum ManagerExitCode {
        MANAGER_RUNNING,
        MANAGER_EXIT,
        MANAGER_RELOAD,
        MANAGER_REEXECUTE,
        MANAGER_REBOOT,
        MANAGER_POWEROFF,
        MANAGER_HALT,
        MANAGER_KEXEC,
        MANAGER_SWITCH_ROOT,
        _MANAGER_EXIT_CODE_MAX,
        _MANAGER_EXIT_CODE_INVALID = -1
} ManagerExitCode;

#include "unit.h"
#include "job.h"
#include "hashmap.h"
#include "list.h"
#include "set.h"
#include "path-lookup.h"
#include "execute.h"
#include "unit-name.h"
#include "exit-status.h"

struct Manager {
        /* Note that the set of units we know of is allowed to be
         * inconsistent. However the subset of it that is loaded may
         * not, and the list of jobs may neither. */

        /* Active jobs and units */
        Hashmap *units;  /* name string => Unit object n:1 */
        Hashmap *jobs;   /* job id => Job object 1:1 */

        /* To make it easy to iterate through the units of a specific
         * type we maintain a per type linked list */
        LIST_HEAD(Unit, units_by_type[_UNIT_TYPE_MAX]);

        /* Units that need to be loaded */
        LIST_HEAD(Unit, load_queue); /* this is actually more a stack than a queue, but uh. */

        /* Jobs that need to be run */
        LIST_HEAD(Job, run_queue);   /* more a stack than a queue, too */

        /* Units and jobs that have not yet been announced via
         * D-Bus. When something about a job changes it is added here
         * if it is not in there yet. This allows easy coalescing of
         * D-Bus change signals. */
        LIST_HEAD(Unit, dbus_unit_queue);
        LIST_HEAD(Job, dbus_job_queue);

        /* Units to remove */
        LIST_HEAD(Unit, cleanup_queue);

        /* Units to check when doing GC */
        LIST_HEAD(Unit, gc_queue);

        /* Units that should be realized */
        LIST_HEAD(Unit, cgroup_queue);

        sd_event *event;

        /* We use two hash tables here, since the same PID might be
         * watched by two different units: once the unit that forked
         * it off, and possibly a different unit to which it was
         * joined as cgroup member. Since we know that it is either
         * one or two units for each PID we just use to hashmaps
         * here. */
        Hashmap *watch_pids1;  /* pid => Unit object n:1 */
        Hashmap *watch_pids2;  /* pid => Unit object n:1 */

        sd_event_source *run_queue_event_source;

        char *notify_socket;
        int notify_fd;
        sd_event_source *notify_event_source;

        int signal_fd;
        sd_event_source *signal_event_source;

        int time_change_fd;
        sd_event_source *time_change_event_source;

        sd_event_source *jobs_in_progress_event_source;

        unsigned n_snapshots;

        LookupPaths lookup_paths;
        Set *unit_path_cache;

        char **environment;

        usec_t runtime_watchdog;
        usec_t shutdown_watchdog;

        dual_timestamp firmware_timestamp;
        dual_timestamp loader_timestamp;
        dual_timestamp kernel_timestamp;
        dual_timestamp initrd_timestamp;
        dual_timestamp userspace_timestamp;
        dual_timestamp finish_timestamp;
        dual_timestamp security_start_timestamp;
        dual_timestamp security_finish_timestamp;
        dual_timestamp generators_start_timestamp;
        dual_timestamp generators_finish_timestamp;
        dual_timestamp units_load_start_timestamp;
        dual_timestamp units_load_finish_timestamp;

        char *generator_unit_path;
        char *generator_unit_path_early;
        char *generator_unit_path_late;

        struct udev* udev;

        /* Data specific to the device subsystem */
        struct udev_monitor* udev_monitor;
        sd_event_source *udev_event_source;
        Hashmap *devices_by_sysfs;

        /* Data specific to the mount subsystem */
        FILE *proc_self_mountinfo;
        sd_event_source *mount_event_source;

        /* Data specific to the swap filesystem */
        FILE *proc_swaps;
        sd_event_source *swap_event_source;
        Hashmap *swaps_by_devnode;

        /* Data specific to the D-Bus subsystem */
        sd_bus *api_bus, *system_bus;
        Set *private_buses;
        int private_listen_fd;
        sd_event_source *private_listen_event_source;
        Set *subscribed;

        sd_bus_message *queued_message; /* This is used during reloading:
                                      * before the reload we queue the
                                      * reply message here, and
                                      * afterwards we send it */
        sd_bus *queued_message_bus; /* The connection to send the queued message on */

        Hashmap *watch_bus;  /* D-Bus names => Unit object n:1 */

        bool send_reloading_done;

        uint32_t current_job_id;
        uint32_t default_unit_job_id;

        /* Data specific to the Automount subsystem */
        int dev_autofs_fd;

        /* Data specific to the cgroup subsystem */
        Hashmap *cgroup_unit;
        CGroupControllerMask cgroup_supported;
        char *cgroup_root;

        int gc_marker;
        unsigned n_in_gc_queue;

        /* Make sure the user cannot accidentally unmount our cgroup
         * file system */
        int pin_cgroupfs_fd;

        /* Flags */
        SystemdRunningAs running_as;
        ManagerExitCode exit_code:5;

        bool dispatching_load_queue:1;
        bool dispatching_dbus_queue:1;

        bool taint_usr:1;

        ShowStatus show_status;
        bool confirm_spawn;
        bool no_console_output;

        ExecOutput default_std_output, default_std_error;

        usec_t default_restart_usec, default_timeout_start_usec,
                default_timeout_stop_usec;

        usec_t default_start_limit_interval;
        unsigned default_start_limit_burst;

        struct rlimit *rlimit[RLIMIT_NLIMITS];

        /* non-zero if we are reloading or reexecuting, */
        int n_reloading;

        unsigned n_installed_jobs;
        unsigned n_failed_jobs;

        /* Jobs in progress watching */
        unsigned n_running_jobs;
        unsigned n_on_console;
        unsigned jobs_in_progress_iteration;

        /* Type=idle pipes */
        int idle_pipe[4];
        sd_event_source *idle_pipe_event_source;

        char *switch_root;
        char *switch_root_init;

        /* This maps all possible path prefixes to the units needing
         * them. It's a hashmap with a path string as key and a Set as
         * value where Unit objects are contained. */
        Hashmap *units_requiring_mounts_for;

        /* Reference to the kdbus bus control fd */
        int kdbus_fd;
};

int manager_new(SystemdRunningAs running_as, Manager **m);
void manager_free(Manager *m);

int manager_enumerate(Manager *m);
int manager_startup(Manager *m, FILE *serialization, FDSet *fds);

Job *manager_get_job(Manager *m, uint32_t id);
Unit *manager_get_unit(Manager *m, const char *name);

int manager_get_unit_by_path(Manager *m, const char *path, const char *suffix, Unit **_found);

int manager_get_job_from_dbus_path(Manager *m, const char *s, Job **_j);

int manager_load_unit_prepare(Manager *m, const char *name, const char *path, sd_bus_error *e, Unit **_ret);
int manager_load_unit(Manager *m, const char *name, const char *path, sd_bus_error *e, Unit **_ret);
int manager_load_unit_from_dbus_path(Manager *m, const char *s, sd_bus_error *e, Unit **_u);

int manager_add_job(Manager *m, JobType type, Unit *unit, JobMode mode, bool force, sd_bus_error *e, Job **_ret);
int manager_add_job_by_name(Manager *m, JobType type, const char *name, JobMode mode, bool force, sd_bus_error *e, Job **_ret);

void manager_dump_units(Manager *s, FILE *f, const char *prefix);
void manager_dump_jobs(Manager *s, FILE *f, const char *prefix);

void manager_clear_jobs(Manager *m);

unsigned manager_dispatch_load_queue(Manager *m);

int manager_environment_add(Manager *m, char **minus, char **plus);
int manager_set_default_rlimits(Manager *m, struct rlimit **default_rlimit);

int manager_loop(Manager *m);

void manager_dispatch_bus_name_owner_changed(Manager *m, const char *name, const char* old_owner, const char *new_owner);

int manager_open_serialization(Manager *m, FILE **_f);

int manager_serialize(Manager *m, FILE *f, FDSet *fds, bool switching_root);
int manager_deserialize(Manager *m, FILE *f, FDSet *fds);

int manager_reload(Manager *m);

bool manager_is_reloading_or_reexecuting(Manager *m) _pure_;

void manager_reset_failed(Manager *m);

void manager_send_unit_audit(Manager *m, Unit *u, int type, bool success);
void manager_send_unit_plymouth(Manager *m, Unit *u);

bool manager_unit_inactive_or_pending(Manager *m, const char *name);

void manager_check_finished(Manager *m);

void manager_run_generators(Manager *m);
void manager_undo_generators(Manager *m);

void manager_recheck_journal(Manager *m);

void manager_set_show_status(Manager *m, ShowStatus mode);
void manager_status_printf(Manager *m, bool ephemeral, const char *status, const char *format, ...) _printf_(4,5);
void manager_flip_auto_status(Manager *m, bool enable);

Set *manager_get_units_requiring_mounts_for(Manager *m, const char *path);