buildkit/source/git/gitsource_unix.go

104 lines
1.8 KiB
Go

//go:build !windows
// +build !windows
package git
import (
"context"
"os"
"os/exec"
"os/signal"
"syscall"
"time"
"github.com/docker/docker/pkg/reexec"
"golang.org/x/sys/unix"
)
const (
gitCmd = "umask-git"
)
func init() {
reexec.Register(gitCmd, gitMain)
}
func gitMain() {
// Need standard user umask for git process.
unix.Umask(0022)
// Reexec git command
cmd := exec.Command(os.Args[1], os.Args[2:]...)
cmd.SysProcAttr = &unix.SysProcAttr{
Setpgid: true,
Pdeathsig: unix.SIGTERM,
}
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
cmd.Stdin = os.Stdin
// Forward all signals
sigc := make(chan os.Signal, 1)
done := make(chan struct{})
signal.Notify(sigc)
go func() {
for {
select {
case sig := <-sigc:
if cmd.Process == nil {
continue
}
switch sig {
case unix.SIGINT, unix.SIGTERM, unix.SIGKILL:
_ = unix.Kill(-cmd.Process.Pid, sig.(unix.Signal))
default:
_ = cmd.Process.Signal(sig)
}
case <-done:
return
}
}
}()
err := cmd.Run()
close(done)
if err != nil {
if exiterr, ok := err.(*exec.ExitError); ok {
switch status := exiterr.Sys().(type) {
case unix.WaitStatus:
os.Exit(status.ExitStatus())
case syscall.WaitStatus:
os.Exit(status.ExitStatus())
}
}
os.Exit(1)
}
os.Exit(0)
}
func runProcessGroup(ctx context.Context, cmd *exec.Cmd) error {
cmd.Path = reexec.Self()
cmd.Args = append([]string{gitCmd}, cmd.Args...)
if err := cmd.Start(); err != nil {
return err
}
waitDone := make(chan struct{})
go func() {
select {
case <-ctx.Done():
_ = unix.Kill(-cmd.Process.Pid, unix.SIGTERM)
go func() {
select {
case <-waitDone:
case <-time.After(10 * time.Second):
_ = unix.Kill(-cmd.Process.Pid, unix.SIGKILL)
}
}()
case <-waitDone:
}
}()
err := cmd.Wait()
close(waitDone)
return err
}