95 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			95 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
| // +build !windows
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| 
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| /*
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|    Copyright The containerd Authors.
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| 
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|    Licensed under the Apache License, Version 2.0 (the "License");
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|    you may not use this file except in compliance with the License.
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|    You may obtain a copy of the License at
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| 
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|        http://www.apache.org/licenses/LICENSE-2.0
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| 
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|    Unless required by applicable law or agreed to in writing, software
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|    distributed under the License is distributed on an "AS IS" BASIS,
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|    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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|    See the License for the specific language governing permissions and
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|    limitations under the License.
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| */
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| 
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| package shim
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| 
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| import (
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| 	"context"
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| 	"io"
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| 	"net"
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| 	"os"
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| 	"os/signal"
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| 	"syscall"
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| 
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| 	"github.com/containerd/containerd/sys/reaper"
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| 	"github.com/containerd/fifo"
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| 	"github.com/pkg/errors"
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| 	"github.com/sirupsen/logrus"
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| 	"golang.org/x/sys/unix"
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| )
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| 
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| // setupSignals creates a new signal handler for all signals and sets the shim as a
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| // sub-reaper so that the container processes are reparented
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| func setupSignals(config Config) (chan os.Signal, error) {
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| 	signals := make(chan os.Signal, 32)
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| 	smp := []os.Signal{unix.SIGTERM, unix.SIGINT, unix.SIGPIPE}
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| 	if !config.NoReaper {
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| 		smp = append(smp, unix.SIGCHLD)
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| 	}
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| 	signal.Notify(signals, smp...)
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| 	return signals, nil
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| }
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| 
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| func setupDumpStacks(dump chan<- os.Signal) {
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| 	signal.Notify(dump, syscall.SIGUSR1)
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| }
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| 
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| func serveListener(path string) (net.Listener, error) {
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| 	var (
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| 		l   net.Listener
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| 		err error
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| 	)
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| 	if path == "" {
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| 		l, err = net.FileListener(os.NewFile(3, "socket"))
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| 		path = "[inherited from parent]"
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| 	} else {
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| 		if len(path) > socketPathLimit {
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| 			return nil, errors.Errorf("%q: unix socket path too long (> %d)", path, socketPathLimit)
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| 		}
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| 		l, err = net.Listen("unix", path)
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| 	}
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| 	if err != nil {
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| 		return nil, err
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| 	}
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| 	logrus.WithField("socket", path).Debug("serving api on socket")
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| 	return l, nil
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| }
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| 
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| func handleSignals(ctx context.Context, logger *logrus.Entry, signals chan os.Signal) error {
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| 	logger.Info("starting signal loop")
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| 
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| 	for {
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| 		select {
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| 		case <-ctx.Done():
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| 			return ctx.Err()
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| 		case s := <-signals:
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| 			switch s {
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| 			case unix.SIGCHLD:
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| 				if err := reaper.Reap(); err != nil {
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| 					logger.WithError(err).Error("reap exit status")
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| 				}
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| 			case unix.SIGPIPE:
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| 			}
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| 		}
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| 	}
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| }
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| 
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| func openLog(ctx context.Context, _ string) (io.Writer, error) {
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| 	return fifo.OpenFifoDup2(ctx, "log", unix.O_WRONLY, 0700, int(os.Stderr.Fd()))
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| }
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