restart

Documentation

Overview

Package restart implements requesting restarts from any part of the code that has access to state. It also implements a mimimal manager to take care of restart state.

Index

• func ClearReboot(st *state.State)
• func FinishTaskWithRestart(t *state.Task, status state.Status, restartType RestartType, snapName string, ...) error
• func MarkTaskAsRestartBoundary(t *state.Task, dir RestartBoundaryDirection)
• func MockAfterRestartForChange(chg *state.Change)
• func PendingForChange(st *state.State, chg *state.Change) bool
• func PendingForChangeTasks(st *state.State, chg *state.Change, considerTasks map[string]bool) bool
• func ReplaceBootID(st *state.State, bootID string)
• func Request(st *state.State, t RestartType, rebootInfo *boot.RebootInfo)
• func TaskIsRestartBoundary(t *state.Task, dir RestartBoundaryDirection) bool
• func TaskWaitForRestart(t *state.Task) error
• type Handler
• type RestartBoundaryDirection
  • func (rb RestartBoundaryDirection) MarshalJSON() ([]byte, error)
  • func (rb *RestartBoundaryDirection) String() string
  • func (rb *RestartBoundaryDirection) UnmarshalJSON(data []byte) error
• type RestartManager
  • func Manager(st *state.State, curBootID string, h Handler) (*RestartManager, error)
  • func (m *RestartManager) Ensure() error
  • func (m *RestartManager) StartUp() error
  • func (rm *RestartManager) Stop()
• type RestartParameters
• type RestartType
  • func MockPending(st *state.State, restarting RestartType) RestartType
  • func Pending(st *state.State) (bool, RestartType)

Functions

func ClearReboot

func ClearReboot(st *state.State)

ClearReboot clears state information about tracking requested reboots.

func FinishTaskWithRestart

func FinishTaskWithRestart(t *state.Task, status state.Status, restartType RestartType, snapName string, rebootInfo *boot.RebootInfo) error

FinishTaskWithRestart either schedules a restart for the given task or it does an immediate restart of the snapd daemon, depending on the type of restart provided. For SystemRestart and friends, the restart is scheduled and postponed until the change has run out of tasks to run. For tasks that request restarts as a part of their undo, any tasks that previously scheduled restarts as a part of their 'do' will be unscheduled.

func MarkTaskAsRestartBoundary

func MarkTaskAsRestartBoundary(t *state.Task, dir RestartBoundaryDirection)

MarkTaskAsRestartBoundary sets a task as a restart boundary. That means the change cannot continue beyond this task, before a restart has taken place. 'path' indicates which execution direction(s) it will be a restart boundary for.

func MockAfterRestartForChange

func MockAfterRestartForChange(chg *state.Change)

MockAfterRestartForChange is added solely for unit test purposes, to help simulate restarts.

func PendingForChange

func PendingForChange(st *state.State, chg *state.Change) bool

PendingForChange checks if a system restart is pending for a change.

func PendingForChangeTasks

func PendingForChangeTasks(st *state.State, chg *state.Change, considerTasks map[string]bool) bool

PendingForChangeTasks checks if a system restart is pending for a change, ignoring tasks other than the task IDs supplied.

func ReplaceBootID

func ReplaceBootID(st *state.State, bootID string)

func Request

func Request(st *state.State, t RestartType, rebootInfo *boot.RebootInfo)

Request asks for a restart of the managing process. The state needs to be locked to request a restart.

func TaskIsRestartBoundary

func TaskIsRestartBoundary(t *state.Task, dir RestartBoundaryDirection) bool

TaskIsRestartBoundary returns true if the task is a restart-boundary for the given direction.

func TaskWaitForRestart

func TaskWaitForRestart(t *state.Task) error

TaskWaitForRestart can be used for tasks that need to wait for a pending restart to occur, meant to be used in conjunction with PendingForChange. The task will then be re-run after the restart has occurred. This is only supported for tasks that are currently in Doing/Undoing and is only safe to call from the task itself. After calling this, the task should immediately return.

Types

type Handler

type Handler interface {
	HandleRestart(t RestartType, rebootInfo *boot.RebootInfo)
	// RebootAsExpected is called early when either a reboot was
	// requested by snapd and happened or no reboot was expected at all.
	RebootAsExpected(st *state.State) error
	// RebootDidNotHappen is called early instead when a reboot was
	// requested by snapd but did not happen.
	RebootDidNotHappen(st *state.State) error
}

Handler can handle restart requests and whether expected reboots happen.

type RestartBoundaryDirection

type RestartBoundaryDirection int

RestartBoundaryDirection defines in which direction a task may have a restart boundary set. A restart boundary is when the task must restart, before it's dependencies can continue. A restart boundary may be either in the 'Do' direction, or the 'Undo' direction.

const (
	// RestartBoundaryDirectionDo is a restart boundary in the 'Do' direction
	RestartBoundaryDirectionDo RestartBoundaryDirection = 1 << iota
	// RestartBoundaryDirectionUndo is a restart boundary in the 'Undo' direction
	RestartBoundaryDirectionUndo RestartBoundaryDirection = 1 << iota
)

func (RestartBoundaryDirection) MarshalJSON

func (rb RestartBoundaryDirection) MarshalJSON() ([]byte, error)

func (*RestartBoundaryDirection) String

func (rb *RestartBoundaryDirection) String() string

func (*RestartBoundaryDirection) UnmarshalJSON

func (rb *RestartBoundaryDirection) UnmarshalJSON(data []byte) error

type RestartManager

type RestartManager struct {
	// contains filtered or unexported fields
}

RestartManager takes care of restart-related state.

func Manager

func Manager(st *state.State, curBootID string, h Handler) (*RestartManager, error)

Manager returns a new restart manager and initializes the support for restarts requests. It takes the current boot id to track and verify reboots and a Handler that handles the actual requests and reacts to reboot happening. It must be called with the state lock held.

func (*RestartManager) Ensure

func (m *RestartManager) Ensure() error

Ensure implements StateManager.Ensure. Required by StateEngine, we actually do nothing here.

func (*RestartManager) StartUp

func (m *RestartManager) StartUp() error

StartUp implements StateStarterUp.Startup.

func (*RestartManager) Stop

func (rm *RestartManager) Stop()

Stop implements StateStopper. It will unregister the change callback handler from state.

type RestartParameters

type RestartParameters struct {
	SnapName          string              `json:"snap-name,omitempty"`
	RestartType       RestartType         `json:"restart-type,omitempty"`
	BootloaderOptions *bootloader.Options `json:"bootloader-options,omitempty"`
}

type RestartType

type RestartType int

const (
	RestartUnset RestartType = iota
	RestartDaemon
	RestartSystem
	// RestartSystemNow is like RestartSystem but action is immediate
	RestartSystemNow
	// RestartSocket will restart the daemon so that it goes into
	// socket activation mode.
	RestartSocket
	// Stop just stops the daemon (used with image pre-seeding)
	StopDaemon
	// RestartSystemHaltNow will shutdown --halt the system asap
	RestartSystemHaltNow
	// RestartSystemPoweroffNow will shutdown --poweroff the system asap
	RestartSystemPoweroffNow
)

func MockPending

func MockPending(st *state.State, restarting RestartType) RestartType

func Pending

func Pending(st *state.State) (bool, RestartType)

Pending returns whether a restart was requested with Request and of which type.