containerd/cmd/ctr/utils.go
Kenfe-Mickael Laventure 0aad42f5cf Add exec and terminal support
Signed-off-by: Kenfe-Mickael Laventure <mickael.laventure@gmail.com>
2016-12-09 10:00:34 -08:00

122 lines
2.6 KiB
Go

package main
import (
"fmt"
"io"
"io/ioutil"
"log"
"net"
"os"
"path/filepath"
"sync"
"syscall"
"time"
gocontext "context"
"github.com/docker/containerd/api/execution"
"github.com/tonistiigi/fifo"
"github.com/urfave/cli"
"google.golang.org/grpc"
"google.golang.org/grpc/grpclog"
)
var grpcConn *grpc.ClientConn
func prepareStdio(in, out, err string) (*sync.WaitGroup, error) {
var (
wg sync.WaitGroup
dst io.Writer
src io.Reader
close func()
)
for _, f := range []struct {
name string
flags int
src bool
reader io.Reader
writer io.Writer
}{
{in, syscall.O_WRONLY | syscall.O_CREAT | syscall.O_NONBLOCK, false, os.Stdin, nil},
{out, syscall.O_RDONLY | syscall.O_CREAT | syscall.O_NONBLOCK, true, nil, os.Stdout},
{err, syscall.O_RDONLY | syscall.O_CREAT | syscall.O_NONBLOCK, true, nil, os.Stderr},
} {
ff, err := fifo.OpenFifo(gocontext.Background(), f.name, f.flags, 0700)
if err != nil {
return nil, err
}
defer func(c io.Closer) {
if err != nil {
c.Close()
}
}(ff)
if f.src {
src = ff
dst = f.writer
close = func() {
ff.Close()
wg.Done()
}
wg.Add(1)
} else {
src = f.reader
dst = ff
close = func() { ff.Close() }
}
go func(dst io.Writer, src io.Reader, close func()) {
io.Copy(dst, src)
close()
}(dst, src, close)
}
return &wg, nil
}
func getGRPCConnection(context *cli.Context) (*grpc.ClientConn, error) {
if grpcConn != nil {
return grpcConn, nil
}
bindSocket := context.GlobalString("socket")
// reset the logger for grpc to log to dev/null so that it does not mess with our stdio
grpclog.SetLogger(log.New(ioutil.Discard, "", log.LstdFlags))
dialOpts := []grpc.DialOption{grpc.WithInsecure(), grpc.WithTimeout(100 * time.Second)}
dialOpts = append(dialOpts,
grpc.WithDialer(func(addr string, timeout time.Duration) (net.Conn, error) {
return net.DialTimeout("unix", bindSocket, timeout)
},
))
conn, err := grpc.Dial(fmt.Sprintf("unix://%s", bindSocket), dialOpts...)
if err != nil {
return nil, err
}
grpcConn = conn
return grpcConn, nil
}
func getExecutionService(context *cli.Context) (execution.ExecutionServiceClient, error) {
conn, err := getGRPCConnection(context)
if err != nil {
return nil, err
}
return execution.NewExecutionServiceClient(conn), nil
}
func getTempDir(id string) (string, error) {
err := os.MkdirAll(filepath.Join(os.TempDir(), "ctr"), 0700)
if err != nil {
return "", err
}
tmpDir, err := ioutil.TempDir(filepath.Join(os.TempDir(), "ctr"), fmt.Sprintf("%s-", id))
if err != nil {
return "", err
}
return tmpDir, nil
}