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Diffstat (limited to 'src/core/job.h')
-rw-r--r-- | src/core/job.h | 230 |
1 files changed, 230 insertions, 0 deletions
diff --git a/src/core/job.h b/src/core/job.h new file mode 100644 index 0000000000..3aa49d4b46 --- /dev/null +++ b/src/core/job.h @@ -0,0 +1,230 @@ +/*-*- 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 <errno.h> + +typedef struct Job Job; +typedef struct JobDependency JobDependency; +typedef struct JobBusClient JobBusClient; +typedef enum JobType JobType; +typedef enum JobState JobState; +typedef enum JobMode JobMode; +typedef enum JobResult JobResult; + +/* Be careful when changing the job types! Adjust job_merging_table[] accordingly! */ +enum JobType { + JOB_START, /* if a unit does not support being started, we'll just wait until it becomes active */ + JOB_VERIFY_ACTIVE, + + JOB_STOP, + + JOB_RELOAD, /* if running, reload */ + + /* Note that restarts are first treated like JOB_STOP, but + * then instead of finishing are patched to become + * JOB_START. */ + JOB_RESTART, /* If running, stop. Then start unconditionally. */ + + _JOB_TYPE_MAX_MERGING, + + /* JOB_NOP can enter into a transaction, but as it won't pull in + * any dependencies, it won't have to merge with anything. + * job_install() avoids the problem of merging JOB_NOP too (it's + * special-cased, only merges with other JOB_NOPs). */ + JOB_NOP = _JOB_TYPE_MAX_MERGING, /* do nothing */ + + _JOB_TYPE_MAX_IN_TRANSACTION, + + /* JOB_TRY_RESTART can never appear in a transaction, because + * it always collapses into JOB_RESTART or JOB_NOP before entering. + * Thus we never need to merge it with anything. */ + JOB_TRY_RESTART = _JOB_TYPE_MAX_IN_TRANSACTION, /* if running, stop and then start */ + + /* JOB_RELOAD_OR_START won't enter into a transaction and cannot result + * from transaction merging (there's no way for JOB_RELOAD and + * JOB_START to meet in one transaction). It can result from a merge + * during job installation, but then it will immediately collapse into + * one of the two simpler types. */ + JOB_RELOAD_OR_START, /* if running, reload, otherwise start */ + + _JOB_TYPE_MAX, + _JOB_TYPE_INVALID = -1 +}; + +enum JobState { + JOB_WAITING, + JOB_RUNNING, + _JOB_STATE_MAX, + _JOB_STATE_INVALID = -1 +}; + +enum JobMode { + JOB_FAIL, /* Fail if a conflicting job is already queued */ + JOB_REPLACE, /* Replace an existing conflicting job */ + JOB_ISOLATE, /* Start a unit, and stop all others */ + JOB_IGNORE_DEPENDENCIES, /* Ignore both requirement and ordering dependencies */ + JOB_IGNORE_REQUIREMENTS, /* Ignore requirement dependencies */ + _JOB_MODE_MAX, + _JOB_MODE_INVALID = -1 +}; + +enum JobResult { + JOB_DONE, /* Job completed successfully */ + JOB_CANCELED, /* Job canceled by a conflicting job installation or by explicit cancel request */ + JOB_TIMEOUT, /* JobTimeout elapsed */ + JOB_FAILED, /* Job failed */ + JOB_DEPENDENCY, /* A required dependency job did not result in JOB_DONE */ + JOB_SKIPPED, /* JOB_RELOAD of inactive unit; negative result of JOB_VERIFY_ACTIVE */ + _JOB_RESULT_MAX, + _JOB_RESULT_INVALID = -1 +}; + +#include "manager.h" +#include "unit.h" +#include "hashmap.h" +#include "list.h" + +struct JobDependency { + /* Encodes that the 'subject' job needs the 'object' job in + * some way. This structure is used only while building a transaction. */ + Job *subject; + Job *object; + + LIST_FIELDS(JobDependency, subject); + LIST_FIELDS(JobDependency, object); + + bool matters; + bool conflicts; +}; + +struct JobBusClient { + LIST_FIELDS(JobBusClient, client); + /* Note that this bus object is not ref counted here. */ + DBusConnection *bus; + char name[0]; +}; + +struct Job { + Manager *manager; + Unit *unit; + + LIST_FIELDS(Job, transaction); + LIST_FIELDS(Job, run_queue); + LIST_FIELDS(Job, dbus_queue); + + LIST_HEAD(JobDependency, subject_list); + LIST_HEAD(JobDependency, object_list); + + /* Used for graph algs as a "I have been here" marker */ + Job* marker; + unsigned generation; + + uint32_t id; + + JobType type; + JobState state; + + Watch timer_watch; + + /* There can be more than one client, because of job merging. */ + LIST_HEAD(JobBusClient, bus_client_list); + + JobResult result; + + bool installed:1; + bool in_run_queue:1; + bool matters_to_anchor:1; + bool override:1; + bool in_dbus_queue:1; + bool sent_dbus_new_signal:1; + bool ignore_order:1; + bool forgot_bus_clients:1; +}; + +JobBusClient* job_bus_client_new(DBusConnection *connection, const char *name); + +Job* job_new(Unit *unit, JobType type); +Job* job_new_raw(Unit *unit); +void job_free(Job *job); +Job* job_install(Job *j); +int job_install_deserialized(Job *j); +void job_uninstall(Job *j); +void job_dump(Job *j, FILE*f, const char *prefix); +int job_serialize(Job *j, FILE *f, FDSet *fds); +int job_deserialize(Job *j, FILE *f, FDSet *fds); +int job_coldplug(Job *j); + +JobDependency* job_dependency_new(Job *subject, Job *object, bool matters, bool conflicts); +void job_dependency_free(JobDependency *l); + +int job_merge(Job *j, Job *other); + +JobType job_type_lookup_merge(JobType a, JobType b); + +static inline bool job_type_is_mergeable(JobType a, JobType b) { + return job_type_lookup_merge(a, b) >= 0; +} + +static inline bool job_type_is_conflicting(JobType a, JobType b) { + return !job_type_is_mergeable(a, b); +} + +static inline bool job_type_is_superset(JobType a, JobType b) { + /* Checks whether operation a is a "superset" of b in its actions */ + return a == job_type_lookup_merge(a, b); +} + +bool job_type_is_redundant(JobType a, UnitActiveState b); + +/* Collapses a state-dependent job type into a simpler type by observing + * the state of the unit which it is going to be applied to. */ +void job_type_collapse(JobType *t, Unit *u); + +int job_type_merge_and_collapse(JobType *a, JobType b, Unit *u); + +bool job_is_runnable(Job *j); + +void job_add_to_run_queue(Job *j); +void job_add_to_dbus_queue(Job *j); + +int job_start_timer(Job *j); +void job_timer_event(Job *j, uint64_t n_elapsed, Watch *w); + +int job_run_and_invalidate(Job *j); +int job_finish_and_invalidate(Job *j, JobResult result, bool recursive); + +char *job_dbus_path(Job *j); + +const char* job_type_to_string(JobType t); +JobType job_type_from_string(const char *s); + +const char* job_state_to_string(JobState t); +JobState job_state_from_string(const char *s); + +const char* job_mode_to_string(JobMode t); +JobMode job_mode_from_string(const char *s); + +const char* job_result_to_string(JobResult t); +JobResult job_result_from_string(const char *s); |