src/core/service.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 /***
   5   This file is part of systemd.
   6
   7   Copyright 2010 Lennart Poettering
   8
   9   systemd is free software; you can redistribute it and/or modify it
  10   under the terms of the GNU Lesser General Public License as published by
  11   the Free Software Foundation; either version 2.1 of the License, or
  12   (at your option) any later version.
  13
  14   systemd is distributed in the hope that it will be useful, but
  15   WITHOUT ANY WARRANTY; without even the implied warranty of
  16   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  17   Lesser General Public License for more details.
  18
  19   You should have received a copy of the GNU Lesser General Public License
  20   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  21 ***/
  22
  23 typedef struct Service Service;
  24 typedef struct ServiceFDStore ServiceFDStore;
  25
  26 #include "exit-status.h"
  27 #include "kill.h"
  28 #include "path.h"
  29 #include "ratelimit.h"
  30
  31 typedef enum ServiceRestart {
  32         SERVICE_RESTART_NO,
  33         SERVICE_RESTART_ON_SUCCESS,
  34         SERVICE_RESTART_ON_FAILURE,
  35         SERVICE_RESTART_ON_ABNORMAL,
  36         SERVICE_RESTART_ON_WATCHDOG,
  37         SERVICE_RESTART_ON_ABORT,
  38         SERVICE_RESTART_ALWAYS,
  39         _SERVICE_RESTART_MAX,
  40         _SERVICE_RESTART_INVALID = -1
  41 } ServiceRestart;
  42
  43 typedef enum ServiceType {
  44         SERVICE_SIMPLE,   /* we fork and go on right-away (i.e. modern socket activated daemons) */
  45         SERVICE_FORKING,  /* forks by itself (i.e. traditional daemons) */
  46         SERVICE_ONESHOT,  /* we fork and wait until the program finishes (i.e. programs like fsck which run and need to finish before we continue) */
  47         SERVICE_DBUS,     /* we fork and wait until a specific D-Bus name appears on the bus */
  48         SERVICE_NOTIFY,   /* we fork and wait until a daemon sends us a ready message with sd_notify() */
  49         SERVICE_IDLE,     /* much like simple, but delay exec() until all jobs are dispatched. */
  50         _SERVICE_TYPE_MAX,
  51         _SERVICE_TYPE_INVALID = -1
  52 } ServiceType;
  53
  54 typedef enum ServiceExecCommand {
  55         SERVICE_EXEC_START_PRE,
  56         SERVICE_EXEC_START,
  57         SERVICE_EXEC_START_POST,
  58         SERVICE_EXEC_RELOAD,
  59         SERVICE_EXEC_STOP,
  60         SERVICE_EXEC_STOP_POST,
  61         _SERVICE_EXEC_COMMAND_MAX,
  62         _SERVICE_EXEC_COMMAND_INVALID = -1
  63 } ServiceExecCommand;
  64
  65 typedef enum NotifyState {
  66         NOTIFY_UNKNOWN,
  67         NOTIFY_READY,
  68         NOTIFY_RELOADING,
  69         NOTIFY_STOPPING,
  70         _NOTIFY_STATE_MAX,
  71         _NOTIFY_STATE_INVALID = -1
  72 } NotifyState;
  73
  74 /* The values of this enum are referenced in man/systemd.exec.xml and src/shared/bus-unit-util.c.
  75  * Update those sources for each change to this enum. */
  76 typedef enum ServiceResult {
  77         SERVICE_SUCCESS,
  78         SERVICE_FAILURE_RESOURCES, /* a bit of a misnomer, just our catch-all error for errnos we didn't expect */
  79         SERVICE_FAILURE_PROTOCOL,
  80         SERVICE_FAILURE_TIMEOUT,
  81         SERVICE_FAILURE_EXIT_CODE,
  82         SERVICE_FAILURE_SIGNAL,
  83         SERVICE_FAILURE_CORE_DUMP,
  84         SERVICE_FAILURE_WATCHDOG,
  85         SERVICE_FAILURE_START_LIMIT_HIT,
  86         _SERVICE_RESULT_MAX,
  87         _SERVICE_RESULT_INVALID = -1
  88 } ServiceResult;
  89
  90 struct ServiceFDStore {
  91         Service *service;
  92
  93         int fd;
  94         char *fdname;
  95         sd_event_source *event_source;
  96
  97         LIST_FIELDS(ServiceFDStore, fd_store);
  98 };
  99
 100 struct Service {
 101         Unit meta;
 102
 103         ServiceType type;
 104         ServiceRestart restart;
 105         ExitStatusSet restart_prevent_status;
 106         ExitStatusSet restart_force_status;
 107         ExitStatusSet success_status;
 108
 109         /* If set we'll read the main daemon PID from this file */
 110         char *pid_file;
 111
 112         usec_t restart_usec;
 113         usec_t timeout_start_usec;
 114         usec_t timeout_stop_usec;
 115         usec_t runtime_max_usec;
 116
 117         dual_timestamp watchdog_timestamp;
 118         usec_t watchdog_usec;
 119         usec_t watchdog_override_usec;
 120         bool watchdog_override_enable;
 121         sd_event_source *watchdog_event_source;
 122
 123         ExecCommand* exec_command[_SERVICE_EXEC_COMMAND_MAX];
 124
 125         ExecContext exec_context;
 126         KillContext kill_context;
 127         CGroupContext cgroup_context;
 128
 129         ServiceState state, deserialized_state;
 130
 131         /* The exit status of the real main process */
 132         ExecStatus main_exec_status;
 133
 134         /* The currently executed control process */
 135         ExecCommand *control_command;
 136
 137         /* The currently executed main process, which may be NULL if
 138          * the main process got started via forking mode and not by
 139          * us */
 140         ExecCommand *main_command;
 141
 142         /* The ID of the control command currently being executed */
 143         ServiceExecCommand control_command_id;
 144
 145         /* Runtime data of the execution context */
 146         ExecRuntime *exec_runtime;
 147         DynamicCreds dynamic_creds;
 148
 149         pid_t main_pid, control_pid;
 150         int socket_fd;
 151         SocketPeer *peer;
 152         bool socket_fd_selinux_context_net;
 153
 154         bool permissions_start_only;
 155         bool root_directory_start_only;
 156         bool remain_after_exit;
 157         bool guess_main_pid;
 158
 159         /* If we shut down, remember why */
 160         ServiceResult result;
 161         ServiceResult reload_result;
 162
 163         bool main_pid_known:1;
 164         bool main_pid_alien:1;
 165         bool bus_name_good:1;
 166         bool forbid_restart:1;
 167         bool start_timeout_defined:1;
 168
 169         bool reset_accounting:1;
 170
 171         char *bus_name;
 172         char *bus_name_owner; /* unique name of the current owner */
 173
 174         char *status_text;
 175         int status_errno;
 176
 177         EmergencyAction emergency_action;
 178
 179         UnitRef accept_socket;
 180
 181         sd_event_source *timer_event_source;
 182         PathSpec *pid_file_pathspec;
 183
 184         NotifyAccess notify_access;
 185         NotifyState notify_state;
 186
 187         ServiceFDStore *fd_store;
 188         unsigned n_fd_store;
 189         unsigned n_fd_store_max;
 190         unsigned n_keep_fd_store;
 191
 192         char *usb_function_descriptors;
 193         char *usb_function_strings;
 194
 195         int stdin_fd;
 196         int stdout_fd;
 197         int stderr_fd;
 198
 199         unsigned n_restarts;
 200         bool flush_n_restarts;
 201 };
 202
 203 extern const UnitVTable service_vtable;
 204
 205 int service_set_socket_fd(Service *s, int fd, struct Socket *socket, bool selinux_context_net);
 206 void service_close_socket_fd(Service *s);
 207
 208 const char* service_restart_to_string(ServiceRestart i) _const_;
 209 ServiceRestart service_restart_from_string(const char *s) _pure_;
 210
 211 const char* service_type_to_string(ServiceType i) _const_;
 212 ServiceType service_type_from_string(const char *s) _pure_;
 213
 214 const char* service_exec_command_to_string(ServiceExecCommand i) _const_;
 215 ServiceExecCommand service_exec_command_from_string(const char *s) _pure_;
 216
 217 const char* notify_state_to_string(NotifyState i) _const_;
 218 NotifyState notify_state_from_string(const char *s) _pure_;
 219
 220 const char* service_result_to_string(ServiceResult i) _const_;
 221 ServiceResult service_result_from_string(const char *s) _pure_;