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-rw-r--r--src/pkg/time/sleep.go177
1 files changed, 0 insertions, 177 deletions
diff --git a/src/pkg/time/sleep.go b/src/pkg/time/sleep.go
deleted file mode 100644
index 314622d0d..000000000
--- a/src/pkg/time/sleep.go
+++ /dev/null
@@ -1,177 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package time
-
-import (
- "container/heap"
- "sync"
-)
-
-// The Timer type represents a single event.
-// When the Timer expires, the current time will be sent on C
-// unless the Timer represents an AfterFunc event.
-type Timer struct {
- C <-chan int64
- t int64 // The absolute time that the event should fire.
- f func(int64) // The function to call when the event fires.
- i int // The event's index inside eventHeap.
-}
-
-type timerHeap []*Timer
-
-// forever is the absolute time (in ns) of an event that is forever away.
-const forever = 1 << 62
-
-// maxSleepTime is the maximum length of time that a sleeper
-// sleeps for before checking if it is defunct.
-const maxSleepTime = 1e9
-
-var (
- // timerMutex guards the variables inside this var group.
- timerMutex sync.Mutex
-
- // timers holds a binary heap of pending events, terminated with a sentinel.
- timers timerHeap
-
- // currentSleeper is an ever-incrementing counter which represents
- // the current sleeper. It allows older sleepers to detect that they are
- // defunct and exit.
- currentSleeper int64
-)
-
-func init() {
- timers.Push(&Timer{t: forever}) // sentinel
-}
-
-// NewTimer creates a new Timer that will send
-// the current time on its channel after at least ns nanoseconds.
-func NewTimer(ns int64) *Timer {
- c := make(chan int64, 1)
- e := after(ns, func(t int64) { c <- t })
- e.C = c
- return e
-}
-
-// After waits at least ns nanoseconds before sending the current time
-// on the returned channel.
-// It is equivalent to NewTimer(ns).C.
-func After(ns int64) <-chan int64 {
- return NewTimer(ns).C
-}
-
-// AfterFunc waits at least ns nanoseconds before calling f
-// in its own goroutine. It returns a Timer that can
-// be used to cancel the call using its Stop method.
-func AfterFunc(ns int64, f func()) *Timer {
- return after(ns, func(_ int64) {
- go f()
- })
-}
-
-// Stop prevents the Timer from firing.
-// It returns true if the call stops the timer, false if the timer has already
-// expired or stopped.
-func (e *Timer) Stop() (ok bool) {
- timerMutex.Lock()
- // Avoid removing the first event in the queue so that
- // we don't start a new sleeper unnecessarily.
- if e.i > 0 {
- heap.Remove(timers, e.i)
- }
- ok = e.f != nil
- e.f = nil
- timerMutex.Unlock()
- return
-}
-
-// after is the implementation of After and AfterFunc.
-// When the current time is after ns, it calls f with the current time.
-// It assumes that f will not block.
-func after(ns int64, f func(int64)) (e *Timer) {
- now := Nanoseconds()
- t := now + ns
- if ns > 0 && t < now {
- panic("time: time overflow")
- }
- timerMutex.Lock()
- t0 := timers[0].t
- e = &Timer{nil, t, f, -1}
- heap.Push(timers, e)
- // Start a new sleeper if the new event is before
- // the first event in the queue. If the length of time
- // until the new event is at least maxSleepTime,
- // then we're guaranteed that the sleeper will wake up
- // in time to service it, so no new sleeper is needed.
- if t0 > t && (t0 == forever || ns < maxSleepTime) {
- currentSleeper++
- go sleeper(currentSleeper)
- }
- timerMutex.Unlock()
- return
-}
-
-// sleeper continually looks at the earliest event in the queue, waits until it happens,
-// then removes any events in the queue that are due. It stops when the queue
-// is empty or when another sleeper has been started.
-func sleeper(sleeperId int64) {
- timerMutex.Lock()
- e := timers[0]
- t := Nanoseconds()
- for e.t != forever {
- if dt := e.t - t; dt > 0 {
- if dt > maxSleepTime {
- dt = maxSleepTime
- }
- timerMutex.Unlock()
- sysSleep(dt)
- timerMutex.Lock()
- if currentSleeper != sleeperId {
- // Another sleeper has been started, making this one redundant.
- break
- }
- }
- e = timers[0]
- t = Nanoseconds()
- for t >= e.t {
- if e.f != nil {
- e.f(t)
- e.f = nil
- }
- heap.Pop(timers)
- e = timers[0]
- }
- }
- timerMutex.Unlock()
-}
-
-func (timerHeap) Len() int {
- return len(timers)
-}
-
-func (timerHeap) Less(i, j int) bool {
- return timers[i].t < timers[j].t
-}
-
-func (timerHeap) Swap(i, j int) {
- timers[i], timers[j] = timers[j], timers[i]
- timers[i].i = i
- timers[j].i = j
-}
-
-func (timerHeap) Push(x interface{}) {
- e := x.(*Timer)
- e.i = len(timers)
- timers = append(timers, e)
-}
-
-func (timerHeap) Pop() interface{} {
- // TODO: possibly shrink array.
- n := len(timers) - 1
- e := timers[n]
- timers[n] = nil
- timers = timers[0:n]
- e.i = -1
- return e
-}