diff options
Diffstat (limited to 'pkg/shim/proc/exec.go')
-rw-r--r-- | pkg/shim/proc/exec.go | 281 |
1 files changed, 281 insertions, 0 deletions
diff --git a/pkg/shim/proc/exec.go b/pkg/shim/proc/exec.go new file mode 100644 index 000000000..1d1d90488 --- /dev/null +++ b/pkg/shim/proc/exec.go @@ -0,0 +1,281 @@ +// Copyright 2018 The containerd Authors. +// Copyright 2018 The gVisor Authors. +// +// 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 +// +// https://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 proc + +import ( + "context" + "fmt" + "io" + "os" + "path/filepath" + "sync" + "syscall" + "time" + + "github.com/containerd/console" + "github.com/containerd/containerd/errdefs" + "github.com/containerd/containerd/pkg/stdio" + "github.com/containerd/fifo" + runc "github.com/containerd/go-runc" + specs "github.com/opencontainers/runtime-spec/specs-go" + "golang.org/x/sys/unix" + + "gvisor.dev/gvisor/pkg/shim/runsc" +) + +type execProcess struct { + wg sync.WaitGroup + + execState execState + + mu sync.Mutex + id string + console console.Console + io runc.IO + status int + exited time.Time + pid int + internalPid int + closers []io.Closer + stdin io.Closer + stdio stdio.Stdio + path string + spec specs.Process + + parent *Init + waitBlock chan struct{} +} + +func (e *execProcess) Wait() { + <-e.waitBlock +} + +func (e *execProcess) ID() string { + return e.id +} + +func (e *execProcess) Pid() int { + e.mu.Lock() + defer e.mu.Unlock() + return e.pid +} + +func (e *execProcess) ExitStatus() int { + e.mu.Lock() + defer e.mu.Unlock() + return e.status +} + +func (e *execProcess) ExitedAt() time.Time { + e.mu.Lock() + defer e.mu.Unlock() + return e.exited +} + +func (e *execProcess) SetExited(status int) { + e.mu.Lock() + defer e.mu.Unlock() + + e.execState.SetExited(status) +} + +func (e *execProcess) setExited(status int) { + e.status = status + e.exited = time.Now() + e.parent.Platform.ShutdownConsole(context.Background(), e.console) + close(e.waitBlock) +} + +func (e *execProcess) Delete(ctx context.Context) error { + e.mu.Lock() + defer e.mu.Unlock() + + return e.execState.Delete(ctx) +} + +func (e *execProcess) delete(ctx context.Context) error { + e.wg.Wait() + if e.io != nil { + for _, c := range e.closers { + c.Close() + } + e.io.Close() + } + pidfile := filepath.Join(e.path, fmt.Sprintf("%s.pid", e.id)) + // silently ignore error + os.Remove(pidfile) + internalPidfile := filepath.Join(e.path, fmt.Sprintf("%s-internal.pid", e.id)) + // silently ignore error + os.Remove(internalPidfile) + return nil +} + +func (e *execProcess) Resize(ws console.WinSize) error { + e.mu.Lock() + defer e.mu.Unlock() + + return e.execState.Resize(ws) +} + +func (e *execProcess) resize(ws console.WinSize) error { + if e.console == nil { + return nil + } + return e.console.Resize(ws) +} + +func (e *execProcess) Kill(ctx context.Context, sig uint32, _ bool) error { + e.mu.Lock() + defer e.mu.Unlock() + + return e.execState.Kill(ctx, sig, false) +} + +func (e *execProcess) kill(ctx context.Context, sig uint32, _ bool) error { + internalPid := e.internalPid + if internalPid != 0 { + if err := e.parent.runtime.Kill(ctx, e.parent.id, int(sig), &runsc.KillOpts{ + Pid: internalPid, + }); err != nil { + // If this returns error, consider the process has + // already stopped. + // + // TODO: Fix after signal handling is fixed. + return fmt.Errorf("%s: %w", err.Error(), errdefs.ErrNotFound) + } + } + return nil +} + +func (e *execProcess) Stdin() io.Closer { + return e.stdin +} + +func (e *execProcess) Stdio() stdio.Stdio { + return e.stdio +} + +func (e *execProcess) Start(ctx context.Context) error { + e.mu.Lock() + defer e.mu.Unlock() + + return e.execState.Start(ctx) +} + +func (e *execProcess) start(ctx context.Context) (err error) { + var ( + socket *runc.Socket + pidfile = filepath.Join(e.path, fmt.Sprintf("%s.pid", e.id)) + internalPidfile = filepath.Join(e.path, fmt.Sprintf("%s-internal.pid", e.id)) + ) + if e.stdio.Terminal { + if socket, err = runc.NewTempConsoleSocket(); err != nil { + return fmt.Errorf("failed to create runc console socket: %w", err) + } + defer socket.Close() + } else if e.stdio.IsNull() { + if e.io, err = runc.NewNullIO(); err != nil { + return fmt.Errorf("creating new NULL IO: %w", err) + } + } else { + if e.io, err = runc.NewPipeIO(e.parent.IoUID, e.parent.IoGID, withConditionalIO(e.stdio)); err != nil { + return fmt.Errorf("failed to create runc io pipes: %w", err) + } + } + opts := &runsc.ExecOpts{ + PidFile: pidfile, + InternalPidFile: internalPidfile, + IO: e.io, + Detach: true, + } + if socket != nil { + opts.ConsoleSocket = socket + } + eventCh := e.parent.Monitor.Subscribe() + defer func() { + // Unsubscribe if an error is returned. + if err != nil { + e.parent.Monitor.Unsubscribe(eventCh) + } + }() + if err := e.parent.runtime.Exec(ctx, e.parent.id, e.spec, opts); err != nil { + close(e.waitBlock) + return e.parent.runtimeError(err, "OCI runtime exec failed") + } + if e.stdio.Stdin != "" { + sc, err := fifo.OpenFifo(context.Background(), e.stdio.Stdin, syscall.O_WRONLY|syscall.O_NONBLOCK, 0) + if err != nil { + return fmt.Errorf("failed to open stdin fifo %s: %w", e.stdio.Stdin, err) + } + e.closers = append(e.closers, sc) + e.stdin = sc + } + ctx, cancel := context.WithTimeout(ctx, 30*time.Second) + defer cancel() + if socket != nil { + console, err := socket.ReceiveMaster() + if err != nil { + return fmt.Errorf("failed to retrieve console master: %w", err) + } + if e.console, err = e.parent.Platform.CopyConsole(ctx, console, e.stdio.Stdin, e.stdio.Stdout, e.stdio.Stderr, &e.wg); err != nil { + return fmt.Errorf("failed to start console copy: %w", err) + } + } else if !e.stdio.IsNull() { + if err := copyPipes(ctx, e.io, e.stdio.Stdin, e.stdio.Stdout, e.stdio.Stderr, &e.wg); err != nil { + return fmt.Errorf("failed to start io pipe copy: %w", err) + } + } + pid, err := runc.ReadPidFile(opts.PidFile) + if err != nil { + return fmt.Errorf("failed to retrieve OCI runtime exec pid: %w", err) + } + e.pid = pid + internalPid, err := runc.ReadPidFile(opts.InternalPidFile) + if err != nil { + return fmt.Errorf("failed to retrieve OCI runtime exec internal pid: %w", err) + } + e.internalPid = internalPid + go func() { + defer e.parent.Monitor.Unsubscribe(eventCh) + for event := range eventCh { + if event.Pid == e.pid { + ExitCh <- Exit{ + Timestamp: event.Timestamp, + ID: e.id, + Status: event.Status, + } + break + } + } + }() + return nil +} + +func (e *execProcess) Status(ctx context.Context) (string, error) { + e.mu.Lock() + defer e.mu.Unlock() + // if we don't have a pid then the exec process has just been created + if e.pid == 0 { + return "created", nil + } + // if we have a pid and it can be signaled, the process is running + // TODO(random-liu): Use `runsc kill --pid`. + if err := unix.Kill(e.pid, 0); err == nil { + return "running", nil + } + // else if we have a pid but it can nolonger be signaled, it has stopped + return "stopped", nil +} |