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|
package signal
import (
"context"
"os"
gosignal "os/signal"
"syscall"
"time"
"github.com/mimecast/dtail/internal/config"
)
// InterruptChWithCancel returns a channel for "please print stats" signalling.
// It accepts a cancel function to properly shutdown when termination signals are received.
func InterruptChWithCancel(ctx context.Context, cancel context.CancelFunc) <-chan string {
sigIntCh := make(chan os.Signal, 10)
gosignal.Notify(sigIntCh, os.Interrupt)
sigOtherCh := make(chan os.Signal, 10)
gosignal.Notify(sigOtherCh, syscall.SIGHUP, syscall.SIGTERM, syscall.SIGQUIT)
statsCh := make(chan string)
go func() {
for {
select {
case <-sigIntCh:
select {
case statsCh <- "Hint: Hit Ctrl+C again to exit":
select {
case <-sigIntCh:
cancel()
// Wait longer to allow MapReduce cleanup, then force exit if still running
go func() {
time.Sleep(5 * time.Second)
os.Exit(0)
}()
case <-time.After(time.Second * time.Duration(config.InterruptTimeoutS)):
}
default:
// Stats already printed.
}
case <-sigOtherCh:
// Cancel context to allow graceful shutdown (MapReduce outfile cleanup, etc.)
cancel()
// Wait longer to allow MapReduce cleanup, then force exit if still running
go func() {
time.Sleep(5 * time.Second)
os.Exit(0)
}()
case <-ctx.Done():
return
}
}
}()
return statsCh
}
// InterruptCh returns a channel for "please print stats" signalling.
// Deprecated: Use InterruptChWithCancel for proper cleanup on termination signals.
func InterruptCh(ctx context.Context) <-chan string {
sigIntCh := make(chan os.Signal, 10)
gosignal.Notify(sigIntCh, os.Interrupt)
sigOtherCh := make(chan os.Signal, 10)
gosignal.Notify(sigOtherCh, syscall.SIGHUP, syscall.SIGTERM, syscall.SIGQUIT)
statsCh := make(chan string)
go func() {
for {
select {
case <-sigIntCh:
select {
case statsCh <- "Hint: Hit Ctrl+C again to exit":
select {
case <-sigIntCh:
os.Exit(0)
case <-time.After(time.Second * time.Duration(config.InterruptTimeoutS)):
}
default:
// Stats already printed.
}
case <-sigOtherCh:
os.Exit(0)
case <-ctx.Done():
return
}
}
}()
return statsCh
}
// NoCh doesn't listen on a signal.
func NoCh(ctx context.Context) <-chan string {
return make(chan string)
}
|
