68 lines
1.1 KiB
Go
68 lines
1.1 KiB
Go
package mutex
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import (
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"errors"
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"sync"
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)
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// Activity represents work that can be started and stopped.
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type Activity struct {
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busy bool
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canceled bool
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mutex sync.Mutex
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}
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// Running checks if the Activity is currently running.
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func (b *Activity) Running() bool {
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b.mutex.Lock()
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defer b.mutex.Unlock()
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return b.busy
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}
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// Start marks the Activity as started and returns an error if it is already running.
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func (b *Activity) Start() error {
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b.mutex.Lock()
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defer b.mutex.Unlock()
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if b.canceled {
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return errors.New("still running")
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}
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if b.busy {
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return errors.New("already running")
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}
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b.busy = true
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b.canceled = false
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return nil
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}
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// Stop marks the Activity as stopped.
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func (b *Activity) Stop() {
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b.mutex.Lock()
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defer b.mutex.Unlock()
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b.busy = false
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b.canceled = false
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}
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// Cancel requests to stop the Activity.
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func (b *Activity) Cancel() {
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b.mutex.Lock()
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defer b.mutex.Unlock()
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if b.busy {
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b.canceled = true
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}
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}
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// Canceled marks the Activity as stopped.
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func (b *Activity) Canceled() bool {
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b.mutex.Lock()
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defer b.mutex.Unlock()
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return b.canceled
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}
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