framework/app/atexit.go

// Copyright (C) 2016 The Android Open Source Project
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package app

import (
	"os"
	"os/signal"
	"time"

	"android.googlesource.com/platform/tools/gpu/framework/log"
	"android.googlesource.com/platform/tools/gpu/framework/task"
)

var (
	// CleanupTimeout is the time to wait for all cleanup signals to fire when shutting down.
	CleanupTimeout = time.Second

	events = task.Events{}
)

// AddCleanupSignal adds a signal the app should wait on when shutting down.
// The signal will automatically be dropped when it is fired, no need unregister it.
func AddCleanupSignal(s ...task.Event) {
	events.Add(s...)
}

// WaitForCleanup waits for all the cleanup signals to fire, or the cleanup timeout to expire,
// whichever comes first.
func WaitForCleanup(ctx log.Context) bool {
	return events.TryWait(ctx, CleanupTimeout)
}

func handleAbortSignals(cancel task.CancelFunc) {
	// register a signal handler for exits
	sigchan := make(chan os.Signal)
	// Enable signal interception, no-op if already enabled.
	// Note: for Unix, these signals translate to SIGINT and SIGKILL.
	signal.Notify(sigchan, os.Interrupt, os.Kill)
	// Run a goroutine that calls the cancel func if the signal is received
	go func() {
		<-sigchan
		cancel()
	}()
}