1 // Copyright 2011 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 package cgotest 6 7 /* 8 // mysleep returns the absolute start time in ms. 9 long long mysleep(int seconds); 10 11 // twoSleep returns the absolute start time of the first sleep 12 // in ms. 13 long long twoSleep(int); 14 */ 15 import "C" 16 17 import ( 18 "testing" 19 "time" 20 ) 21 22 var sleepDone = make(chan int64) 23 24 // parallelSleep returns the absolute difference between the start time 25 // of the two sleeps. 26 func parallelSleep(n int) int64 { 27 t := int64(C.twoSleep(C.int(n))) - <-sleepDone 28 if t < 0 { 29 return -t 30 } 31 return t 32 } 33 34 //export BackgroundSleep 35 func BackgroundSleep(n int32) { 36 go func() { 37 sleepDone <- int64(C.mysleep(C.int(n))) 38 }() 39 } 40 41 func testParallelSleep(t *testing.T) { 42 sleepSec := 1 43 dt := time.Duration(parallelSleep(sleepSec)) * time.Millisecond 44 t.Logf("difference in start time for two sleep(%d) is %v", sleepSec, dt) 45 // bug used to run sleeps in serial, producing a 2*sleepSec-second delay. 46 // we detect if the start times of those sleeps are > 0.5*sleepSec-second. 47 if dt >= time.Duration(sleepSec)*time.Second/2 { 48 t.Fatalf("parallel %d-second sleeps slept for %f seconds", sleepSec, dt.Seconds()) 49 } 50 } 51
