| 95 | } |
| 96 | |
| 97 | func (v *Queue) dequeue(ctx context.Context) CallbackFunc { |
| 98 | v.monitor.L.Lock() |
| 99 | defer v.monitor.L.Unlock() |
| 100 | |
| 101 | for v.queueItems.Len() == 0 && v.activeWorkerCount > 0 { |
| 102 | // no items in queue, but some workers are active, they may add more. |
| 103 | v.monitor.Wait() |
| 104 | } |
| 105 | |
| 106 | // no items in queue, no workers are active, no more work. |
| 107 | if v.queueItems.Len() == 0 { |
| 108 | return nil |
| 109 | } |
| 110 | |
| 111 | v.activeWorkerCount++ |
| 112 | v.maybeReportProgress(ctx) |
| 113 | |
| 114 | front := v.queueItems.Front() |
| 115 | v.queueItems.Remove(front) |
| 116 | |
| 117 | return front.Value.(CallbackFunc) //nolint:forcetypeassert |
| 118 | } |
| 119 | |
| 120 | func (v *Queue) completed(ctx context.Context) { |
| 121 | v.monitor.L.Lock() |