From 5e03cec7ec83f8ff8b31a89a6180dda203b04d9c Mon Sep 17 00:00:00 2001 From: Matthew Heon Date: Wed, 11 Apr 2018 13:09:41 -0400 Subject: Changes to attach to enable per-stream attaching This allows us to attach to attach to just stdout or stderr or stdin, or any combination of these. Signed-off-by: Matthew Heon Closes: #608 Approved by: baude --- cmd/podman/attach.go | 9 +++++- cmd/podman/run.go | 39 +++++++++++++++++++++-- cmd/podman/start.go | 9 ++++-- cmd/podman/utils.go | 87 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 138 insertions(+), 6 deletions(-) (limited to 'cmd') diff --git a/cmd/podman/attach.go b/cmd/podman/attach.go index 20c1c306d..4b16d013c 100644 --- a/cmd/podman/attach.go +++ b/cmd/podman/attach.go @@ -1,6 +1,8 @@ package main import ( + "os" + "github.com/pkg/errors" "github.com/projectatomic/libpod/libpod" "github.com/urfave/cli" @@ -71,7 +73,12 @@ func attachCmd(c *cli.Context) error { ProxySignals(ctr) } - if err := ctr.Attach(c.Bool("no-stdin"), c.String("detach-keys")); err != nil { + inputStream := os.Stdin + if c.Bool("no-stdin") { + inputStream = nil + } + + if err := attachCtr(ctr, os.Stdout, os.Stderr, inputStream, c.String("detach-keys")); err != nil { return errors.Wrapf(err, "error attaching to container %s", ctr.ID()) } diff --git a/cmd/podman/run.go b/cmd/podman/run.go index 4966316c5..b8d6e0968 100644 --- a/cmd/podman/run.go +++ b/cmd/podman/run.go @@ -144,9 +144,42 @@ func runCmd(c *cli.Context) error { return nil } - // TODO: that "false" should probably be linked to -i - // Handle this when we split streams to allow attaching just stdin/out/err - attachChan, err := ctr.StartAndAttach(false, c.String("detach-keys")) + outputStream := os.Stdout + errorStream := os.Stderr + inputStream := os.Stdin + + // If -i is not set, clear stdin + if !c.Bool("interactive") { + inputStream = nil + } + + // If attach is set, clear stdin/stdout/stderr and only attach requested + if c.IsSet("attach") { + outputStream = nil + errorStream = nil + inputStream = nil + + attachTo := c.StringSlice("attach") + for _, stream := range attachTo { + switch strings.ToLower(stream) { + case "stdout": + outputStream = os.Stdout + case "stderr": + errorStream = os.Stderr + case "stdin": + inputStream = os.Stdin + default: + return errors.Wrapf(libpod.ErrInvalidArg, "invalid stream %q for --attach - must be one of stdin, stdout, or stderr", stream) + } + } + + // If --interactive is set, restore stdin + if c.Bool("interactive") { + inputStream = os.Stdin + } + } + + attachChan, err := startAttachCtr(ctr, outputStream, errorStream, inputStream, c.String("detach-keys")) if err != nil { // This means the command did not exist exitCode = 127 diff --git a/cmd/podman/start.go b/cmd/podman/start.go index 1a57a538b..14b03ac7c 100644 --- a/cmd/podman/start.go +++ b/cmd/podman/start.go @@ -95,7 +95,7 @@ func startCmd(c *cli.Context) error { if c.Bool("interactive") && !ctr.Config().Stdin { return errors.Errorf("the container was not created with the interactive option") } - noStdIn := c.Bool("interactive") + tty, err := strconv.ParseBool(ctr.Spec().Annotations["io.kubernetes.cri-o.TTY"]) if err != nil { return errors.Wrapf(err, "unable to parse annotations in %s", ctr.ID()) @@ -105,7 +105,12 @@ func startCmd(c *cli.Context) error { // We only get a terminal session if both a tty was specified in the spec and // -a on the command-line was given. if attach && tty { - attachChan, err := ctr.StartAndAttach(noStdIn, c.String("detach-keys")) + inputStream := os.Stdin + if !c.Bool("interactive") { + inputStream = nil + } + + attachChan, err := startAttachCtr(ctr, os.Stdout, os.Stderr, inputStream, c.String("detach-keys")) if err != nil { return errors.Wrapf(err, "unable to start container %s", ctr.ID()) } diff --git a/cmd/podman/utils.go b/cmd/podman/utils.go index 8b59e1344..502424403 100644 --- a/cmd/podman/utils.go +++ b/cmd/podman/utils.go @@ -1,9 +1,18 @@ package main import ( + "os" + gosignal "os/signal" + "github.com/containers/storage" + "github.com/docker/docker/pkg/signal" + "github.com/docker/docker/pkg/term" + "github.com/pkg/errors" "github.com/projectatomic/libpod/libpod" + "github.com/sirupsen/logrus" "github.com/urfave/cli" + "golang.org/x/crypto/ssh/terminal" + "k8s.io/client-go/tools/remotecommand" ) // Generate a new libpod runtime configured by command line options @@ -54,3 +63,81 @@ func getRuntime(c *cli.Context) (*libpod.Runtime, error) { return libpod.NewRuntime(options...) } + +// Attach to a container +func attachCtr(ctr *libpod.Container, stdout, stderr, stdin *os.File, detachKeys string) error { + resize := make(chan remotecommand.TerminalSize) + + haveTerminal := terminal.IsTerminal(int(os.Stdin.Fd())) + + // Check if we are attached to a terminal. If we are, generate resize + // events, and set the terminal to raw mode + if haveTerminal { + logrus.Debugf("Handling terminal attach") + + resizeTty(resize) + + oldTermState, err := term.SaveState(os.Stdin.Fd()) + if err != nil { + return errors.Wrapf(err, "unable to save terminal state") + } + + term.SetRawTerminal(os.Stdin.Fd()) + + defer term.RestoreTerminal(os.Stdin.Fd(), oldTermState) + } + + return ctr.Attach(stdout, stderr, stdin, detachKeys, resize) +} + +// Start and attach to a container +func startAttachCtr(ctr *libpod.Container, stdout, stderr, stdin *os.File, detachKeys string) (<-chan error, error) { + resize := make(chan remotecommand.TerminalSize) + + haveTerminal := terminal.IsTerminal(int(os.Stdin.Fd())) + + // Check if we are attached to a terminal. If we are, generate resize + // events, and set the terminal to raw mode + if haveTerminal && ctr.Spec().Process.Terminal { + logrus.Debugf("Handling terminal attach") + + resizeTty(resize) + + oldTermState, err := term.SaveState(os.Stdin.Fd()) + if err != nil { + return nil, errors.Wrapf(err, "unable to save terminal state") + } + + term.SetRawTerminal(os.Stdin.Fd()) + + defer term.RestoreTerminal(os.Stdin.Fd(), oldTermState) + } + + return ctr.StartAndAttach(stdout, stderr, stdin, detachKeys, resize) +} + +// Helper for prepareAttach - set up a goroutine to generate terminal resize events +func resizeTty(resize chan remotecommand.TerminalSize) { + sigchan := make(chan os.Signal, 1) + gosignal.Notify(sigchan, signal.SIGWINCH) + sendUpdate := func() { + winsize, err := term.GetWinsize(os.Stdin.Fd()) + if err != nil { + logrus.Warnf("Could not get terminal size %v", err) + return + } + resize <- remotecommand.TerminalSize{ + Width: winsize.Width, + Height: winsize.Height, + } + } + go func() { + defer close(resize) + // Update the terminal size immediately without waiting + // for a SIGWINCH to get the correct initial size. + sendUpdate() + for range sigchan { + sendUpdate() + } + }() +} -- cgit v1.2.3-54-g00ecf