github.com/openebs/api@v1.12.0/pkg/util/signals/signal.go (about)

     1  /*
     2  Copyright 2018 The OpenEBS Authors.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package signals
    18  
    19  import (
    20  	"os"
    21  	"os/signal"
    22  )
    23  
    24  var onlyOneSignalHandler = make(chan struct{})
    25  
    26  // SetupSignalHandler registered for SIGTERM and SIGINT. A stop channel is returned
    27  // which is closed on one of these signals. If a second signal is caught, the program
    28  // is terminated with exit code 1.
    29  func SetupSignalHandler() (stopCh <-chan struct{}) {
    30  	//	close(onlyOneSignalHandler) // panics when called twice
    31  
    32  	stop := make(chan struct{})
    33  	c := make(chan os.Signal, 2)
    34  	signal.Notify(c, shutdownSignals...)
    35  	go func() {
    36  		<-c
    37  		close(stop)
    38  		<-c
    39  		os.Exit(1) // second signal. Exit directly.
    40  	}()
    41  
    42  	return stop
    43  }