opensource/podman
1
0
Fork 0
mirror of https://github.com/containers/podman.git synced 2025-08-06 11:32:07 +08:00
Code Issues Packages Projects Releases Wiki Activity

Remove duplicated exec handling code

Browse Source 
During the initial workup of HTTP exec, I duplicated most of the
existing exec handling code so I could work on it without
breaking normal exec (and compare what I was doing to the nroaml
version). Now that it's done and working, we can switch over to
the refactored version and ditch the original, removing a lot of
duplicated code.

Signed-off-by: Matthew Heon <matthew.heon@pm.me>
This commit is contained in:
Matthew Heon
2020-05-14 17:32:44 -04:00
parent a6d9cf9a5e
commit 50ed292aee
1 changed files with 15 additions and 162 deletions
Download Patch File Download Diff File Expand all files Collapse all files

177
libpod/oci_conmon_linux.go
View File

@ -636,7 +636,6 @@ func (r *ConmonOCIRuntime) AttachResize(ctr *Container, newSize remotecommand.Te
}
// ExecContainer executes a command in a running container
// TODO: Split into Create/Start/Attach/Wait
func (r *ConmonOCIRuntime) ExecContainer(c *Container, sessionID string, options *ExecOptions, streams *define.AttachStreams) (int, chan error, error) {
if options == nil {
return -1, nil, errors.Wrapf(define.ErrInvalidArg, "must provide an ExecOptions struct to ExecContainer")
@ -649,178 +648,46 @@ func (r *ConmonOCIRuntime) ExecContainer(c *Container, sessionID string, options
return -1, nil, errors.Wrapf(define.ErrEmptyID, "must provide a session ID for exec")
}
// create sync pipe to receive the pid
parentSyncPipe, childSyncPipe, err := newPipe()
if err != nil {
return -1, nil, errors.Wrapf(err, "error creating socket pair")
}
defer errorhandling.CloseQuiet(parentSyncPipe)
// create start pipe to set the cgroup before running
// attachToExec is responsible for closing parentStartPipe
childStartPipe, parentStartPipe, err := newPipe()
if err != nil {
return -1, nil, errors.Wrapf(err, "error creating socket pair")
}
// We want to make sure we close the parent{Start,Attach}Pipes if we fail
// but also don't want to close them after attach to exec is called
attachToExecCalled := false
defer func() {
if !attachToExecCalled {
errorhandling.CloseQuiet(parentStartPipe)
}
}()
// create the attach pipe to allow attach socket to be created before
// $RUNTIME exec starts running. This is to make sure we can capture all output
// from the process through that socket, rather than half reading the log, half attaching to the socket
// attachToExec is responsible for closing parentAttachPipe
parentAttachPipe, childAttachPipe, err := newPipe()
if err != nil {
return -1, nil, errors.Wrapf(err, "error creating socket pair")
}
defer func() {
if !attachToExecCalled {
errorhandling.CloseQuiet(parentAttachPipe)
}
}()
childrenClosed := false
defer func() {
if !childrenClosed {
errorhandling.CloseQuiet(childSyncPipe)
errorhandling.CloseQuiet(childAttachPipe)
errorhandling.CloseQuiet(childStartPipe)
}
}()
runtimeDir, err := util.GetRuntimeDir()
if err != nil {
return -1, nil, err
}
finalEnv := make([]string, 0, len(options.Env))
for k, v := range options.Env {
finalEnv = append(finalEnv, fmt.Sprintf("%s=%s", k, v))
}
processFile, err := prepareProcessExec(c, options.Cmd, finalEnv, options.Terminal, options.Cwd, options.User, sessionID)
if err != nil {
return -1, nil, err
// TODO: Should we default this to false?
// Or maybe make streams mandatory?
attachStdin := true
if streams != nil {
attachStdin = streams.AttachInput
}
var ociLog string
if logrus.GetLevel() != logrus.DebugLevel && r.supportsJSON {
ociLog = c.execOCILog(sessionID)
}
args := r.sharedConmonArgs(c, sessionID, c.execBundlePath(sessionID), c.execPidPath(sessionID), c.execLogPath(sessionID), c.execExitFileDir(sessionID), ociLog, "")
if options.PreserveFDs > 0 {
args = append(args, formatRuntimeOpts("--preserve-fds", fmt.Sprintf("%d", options.PreserveFDs))...)
}
for _, capability := range options.CapAdd {
args = append(args, formatRuntimeOpts("--cap", capability)...)
}
if options.Terminal {
args = append(args, "-t")
}
if streams != nil && streams.AttachInput {
args = append(args, "-i")
}
// Append container ID and command
args = append(args, "-e")
// TODO make this optional when we can detach
args = append(args, "--exec-attach")
args = append(args, "--exec-process-spec", processFile.Name())
logrus.WithFields(logrus.Fields{
"args": args,
}).Debugf("running conmon: %s", r.conmonPath)
execCmd := exec.Command(r.conmonPath, args...)
if streams != nil {
// Don't add the InputStream to the execCmd. Instead, the data should be passed
// through CopyDetachable
if streams.AttachOutput {
execCmd.Stdout = options.Streams.OutputStream
}
if streams.AttachError {
execCmd.Stderr = options.Streams.ErrorStream
}
}
conmonEnv, extraFiles, err := r.configureConmonEnv(runtimeDir)
execCmd, pipes, err := r.startExec(c, sessionID, options, attachStdin, ociLog)
if err != nil {
return -1, nil, err
}
if options.PreserveFDs > 0 {
for fd := 3; fd < int(3+options.PreserveFDs); fd++ {
execCmd.ExtraFiles = append(execCmd.ExtraFiles, os.NewFile(uintptr(fd), fmt.Sprintf("fd-%d", fd)))
// Only close sync pipe. Start and attach are consumed in the attach
// goroutine.
defer func() {
if pipes.syncPipe != nil && !pipes.syncClosed {
errorhandling.CloseQuiet(pipes.syncPipe)
pipes.syncClosed = true
}
}
// we don't want to step on users fds they asked to preserve
// Since 0-2 are used for stdio, start the fds we pass in at preserveFDs+3
execCmd.Env = r.conmonEnv
execCmd.Env = append(execCmd.Env, fmt.Sprintf("_OCI_SYNCPIPE=%d", options.PreserveFDs+3), fmt.Sprintf("_OCI_STARTPIPE=%d", options.PreserveFDs+4), fmt.Sprintf("_OCI_ATTACHPIPE=%d", options.PreserveFDs+5))
execCmd.Env = append(execCmd.Env, conmonEnv...)
execCmd.ExtraFiles = append(execCmd.ExtraFiles, childSyncPipe, childStartPipe, childAttachPipe)
execCmd.ExtraFiles = append(execCmd.ExtraFiles, extraFiles...)
execCmd.Dir = c.execBundlePath(sessionID)
execCmd.SysProcAttr = &syscall.SysProcAttr{
Setpgid: true,
}
err = startCommandGivenSelinux(execCmd)
// We don't need children pipes on the parent side
errorhandling.CloseQuiet(childSyncPipe)
errorhandling.CloseQuiet(childAttachPipe)
errorhandling.CloseQuiet(childStartPipe)
childrenClosed = true
if err != nil {
return -1, nil, errors.Wrapf(err, "cannot start container %s", c.ID())
}
if err := r.moveConmonToCgroupAndSignal(c, execCmd, parentStartPipe); err != nil {
return -1, nil, err
}
if options.PreserveFDs > 0 {
for fd := 3; fd < int(3+options.PreserveFDs); fd++ {
// These fds were passed down to the runtime. Close them
// and not interfere
if err := os.NewFile(uintptr(fd), fmt.Sprintf("fd-%d", fd)).Close(); err != nil {
logrus.Debugf("unable to close file fd-%d", fd)
}
}
}
}()
// TODO Only create if !detach
// Attach to the container before starting it
attachChan := make(chan error)
go func() {
// attachToExec is responsible for closing pipes
attachChan <- c.attachToExec(streams, options.DetachKeys, sessionID, parentStartPipe, parentAttachPipe)
attachChan <- c.attachToExec(streams, options.DetachKeys, sessionID, pipes.startPipe, pipes.attachPipe)
close(attachChan)
}()
attachToExecCalled = true
if err := execCmd.Wait(); err != nil {
return -1, nil, errors.Wrapf(err, "cannot run conmon")
}
pid, err := readConmonPipeData(parentSyncPipe, ociLog)
pid, err := readConmonPipeData(pipes.syncPipe, ociLog)
return pid, attachChan, err
}
@ -1949,9 +1816,6 @@ func (r *ConmonOCIRuntime) startExec(c *Container, sessionID string, options *Ex
}
}()
// TODOTODOTODO
//defer errorhandling.CloseQuiet(parentSyncPipe)
// create start pipe to set the cgroup before running
// attachToExec is responsible for closing parentStartPipe
childStartPipe, parentStartPipe, err := newPipe()
@ -1960,17 +1824,6 @@ func (r *ConmonOCIRuntime) startExec(c *Container, sessionID string, options *Ex
}
pipes.startPipe = parentStartPipe
// We want to make sure we close the parent{Start,Attach}Pipes if we fail
// but also don't want to close them after attach to exec is called
//attachToExecCalled := false
// TODOTODOTODO
// defer func() {
// if !attachToExecCalled {
// errorhandling.CloseQuiet(parentStartPipe)
// }
// }()
// create the attach pipe to allow attach socket to be created before
// $RUNTIME exec starts running. This is to make sure we can capture all output
// from the process through that socket, rather than half reading the log, half attaching to the socket