()
| 67 | } |
| 68 | |
| 69 | func (r *RingBufferRateLimiter) loop() { |
| 70 | defer func() { |
| 71 | if err := recover(); err != nil { |
| 72 | buf := make([]byte, stackTraceBufferSize) |
| 73 | buf = buf[:runtime.Stack(buf, false)] |
| 74 | log.Printf("panic: ring buffer rate limiter: %v\n%s", err, buf) |
| 75 | } |
| 76 | }() |
| 77 | |
| 78 | for { |
| 79 | // if we've been stopped, return |
| 80 | select { |
| 81 | case <-r.stopped: |
| 82 | return |
| 83 | default: |
| 84 | } |
| 85 | |
| 86 | if len(r.ring) == 0 { |
| 87 | if r.window == 0 { |
| 88 | // rate limiting is disabled; always allow immediately |
| 89 | r.permit() |
| 90 | continue |
| 91 | } |
| 92 | panic("invalid configuration: maxEvents = 0 and window != 0 does not allow any events") |
| 93 | } |
| 94 | |
| 95 | // wait until next slot is available or until we've been stopped |
| 96 | r.mu.Lock() |
| 97 | then := r.ring[r.cursor].Add(r.window) |
| 98 | r.mu.Unlock() |
| 99 | waitDuration := time.Until(then) |
| 100 | waitTimer := time.NewTimer(waitDuration) |
| 101 | select { |
| 102 | case <-waitTimer.C: |
| 103 | r.permit() |
| 104 | case <-r.stopped: |
| 105 | waitTimer.Stop() |
| 106 | return |
| 107 | } |
| 108 | } |
| 109 | } |
| 110 | |
| 111 | // Allow returns true if the event is allowed to |
| 112 | // happen right now. It does not wait. If the event |
no test coverage detected