source: code/trunk/vendor/github.com/valyala/fasthttp/timer.go@ 145

package fasthttp

import (
        "sync"
        "time"
)

func initTimer(t *time.Timer, timeout time.Duration) *time.Timer {
        if t == nil {
                return time.NewTimer(timeout)
        }
        if t.Reset(timeout) {
                panic("BUG: active timer trapped into initTimer()")
        }
        return t
}

func stopTimer(t *time.Timer) {
        if !t.Stop() {
                // Collect possibly added time from the channel
                // if timer has been stopped and nobody collected its' value.
                select {
                case <-t.C:
                default:
                }
        }
}

// AcquireTimer returns a time.Timer from the pool and updates it to
// send the current time on its channel after at least timeout.
//
// The returned Timer may be returned to the pool with ReleaseTimer
// when no longer needed. This allows reducing GC load.
func AcquireTimer(timeout time.Duration) *time.Timer {
        v := timerPool.Get()
        if v == nil {
                return time.NewTimer(timeout)
        }
        t := v.(*time.Timer)
        initTimer(t, timeout)
        return t
}

// ReleaseTimer returns the time.Timer acquired via AcquireTimer to the pool
// and prevents the Timer from firing.
//
// Do not access the released time.Timer or read from it's channel otherwise
// data races may occur.
func ReleaseTimer(t *time.Timer) {
        stopTimer(t)
        timerPool.Put(t)
}

var timerPool sync.Pool