From cd73a6904d3dc91f305c7415ab7bada8a976d815 Mon Sep 17 00:00:00 2001 From: Matthew Heon Date: Sun, 4 Mar 2018 12:24:56 -0500 Subject: Add signal proxying to podman run, start, and attach Also removes sig-proxy from 'podman create', where is does not make sense. Signed-off-by: Matthew Heon --- cmd/podman/attach.go | 8 ++++++++ cmd/podman/common.go | 4 ---- cmd/podman/create.go | 2 -- cmd/podman/run.go | 11 ++++++++++- cmd/podman/sigproxy.go | 33 +++++++++++++++++++++++++++++++++ cmd/podman/start.go | 12 ++++++++++++ 6 files changed, 63 insertions(+), 7 deletions(-) create mode 100644 cmd/podman/sigproxy.go (limited to 'cmd') diff --git a/cmd/podman/attach.go b/cmd/podman/attach.go index 7f7e4d192..20c1c306d 100644 --- a/cmd/podman/attach.go +++ b/cmd/podman/attach.go @@ -16,6 +16,10 @@ var ( Name: "no-stdin", Usage: "Do not attach STDIN. The default is false.", }, + cli.BoolTFlag{ + Name: "sig-proxy", + Usage: "proxy received signals to the process (default true)", + }, LatestFlag, } attachDescription = "The podman attach command allows you to attach to a running container using the container's ID or name, either to view its ongoing output or to control it interactively." @@ -63,6 +67,10 @@ func attachCmd(c *cli.Context) error { return errors.Errorf("you can only attach to running containers") } + if c.BoolT("sig-proxy") { + ProxySignals(ctr) + } + if err := ctr.Attach(c.Bool("no-stdin"), c.String("detach-keys")); err != nil { return errors.Wrapf(err, "error attaching to container %s", ctr.ID()) } diff --git a/cmd/podman/common.go b/cmd/podman/common.go index 60cc48803..93de80e29 100644 --- a/cmd/podman/common.go +++ b/cmd/podman/common.go @@ -334,10 +334,6 @@ var createFlags = []cli.Flag{ Usage: "Size of `/dev/shm`. The format is ``.", Value: "65536k", }, - cli.BoolFlag{ - Name: "sig-proxy", - Usage: "Proxy received signals to the process (default true)", - }, cli.StringFlag{ Name: "stop-signal", Usage: "Signal to stop a container. Default is SIGTERM", diff --git a/cmd/podman/create.go b/cmd/podman/create.go index 462c56a51..efd7458ea 100644 --- a/cmd/podman/create.go +++ b/cmd/podman/create.go @@ -117,7 +117,6 @@ type createConfig struct { Resources createResourceConfig Rm bool //rm ShmDir string - SigProxy bool //sig-proxy StopSignal syscall.Signal // stop-signal StopTimeout uint // stop-timeout Sysctl map[string]string //sysctl @@ -715,7 +714,6 @@ func parseCreateOpts(c *cli.Context, runtime *libpod.Runtime, imageName string, }, Rm: c.Bool("rm"), ShmDir: shmDir, - SigProxy: c.Bool("sig-proxy"), StopSignal: stopSignal, StopTimeout: c.Uint("stop-timeout"), Sysctl: sysctl, diff --git a/cmd/podman/run.go b/cmd/podman/run.go index f68db9036..7b840a387 100644 --- a/cmd/podman/run.go +++ b/cmd/podman/run.go @@ -13,11 +13,16 @@ import ( var runDescription = "Runs a command in a new container from the given image" +var runFlags []cli.Flag = append(createFlags, cli.BoolTFlag{ + Name: "sig-proxy", + Usage: "proxy received signals to the process (default true)", +}) + var runCommand = cli.Command{ Name: "run", Usage: "run a command in a new container", Description: runDescription, - Flags: createFlags, + Flags: runFlags, Action: runCmd, ArgsUsage: "IMAGE [COMMAND [ARG...]]", SkipArgReorder: true, @@ -133,6 +138,10 @@ func runCmd(c *cli.Context) error { return errors.Wrapf(err, "unable to start container %q", ctr.ID()) } + if c.BoolT("sig-proxy") { + ProxySignals(ctr) + } + // Wait for attach to complete err = <-attachChan if err != nil { diff --git a/cmd/podman/sigproxy.go b/cmd/podman/sigproxy.go new file mode 100644 index 000000000..fd1415dc6 --- /dev/null +++ b/cmd/podman/sigproxy.go @@ -0,0 +1,33 @@ +package main + +import ( + "os" + "syscall" + + "github.com/docker/docker/pkg/signal" + "github.com/projectatomic/libpod/libpod" + "github.com/sirupsen/logrus" +) + +func ProxySignals(ctr *libpod.Container) { + sigBuffer := make(chan os.Signal, 128) + signal.CatchAll(sigBuffer) + + logrus.Debugf("Enabling signal proxying") + + go func() { + for s := range sigBuffer { + // Ignore SIGCHLD and SIGPIPE - these are mostly likely + // intended for the podman command itself. + if s == signal.SIGCHLD || s == signal.SIGPIPE { + continue + } + + if err := ctr.Kill(uint(s.(syscall.Signal))); err != nil { + logrus.Errorf("Error forwarding signal %d to container %s: %v", s, ctr.ID(), err) + } + } + }() + + return +} diff --git a/cmd/podman/start.go b/cmd/podman/start.go index c90fab645..366d5c3fc 100644 --- a/cmd/podman/start.go +++ b/cmd/podman/start.go @@ -25,6 +25,10 @@ var ( Name: "interactive, i", Usage: "Keep STDIN open even if not attached", }, + cli.BoolFlag{ + Name: "sig-proxy", + Usage: "proxy received signals to the process", + }, LatestFlag, } startDescription = ` @@ -60,6 +64,10 @@ func startCmd(c *cli.Context) error { return err } + if c.Bool("sig-proxy") && !attach { + return errors.Wrapf(libpod.ErrInvalidArg, "you cannot use sig-proxy without --attach") + } + runtime, err := getRuntime(c) if err != nil { return errors.Wrapf(err, "error creating libpod runtime") @@ -106,6 +114,10 @@ func startCmd(c *cli.Context) error { return errors.Wrapf(err, "unable to start container %s", ctr.ID()) } + if c.Bool("sig-proxy") { + ProxySignals(ctr) + } + // Wait for attach to complete err = <-attachChan if err != nil { -- cgit v1.2.3-54-g00ecf