package util

import (
	"syscall"

	"github.com/opencontainers/runc/libcontainer/utils"
)

// Exit is the wait4 information from an exited process
type Exit struct {
	Pid    int
	Status int
}

// Reap reaps all child processes for the calling process and returns their
// exit information
func Reap() (exits []Exit, err error) {
	var (
		ws  syscall.WaitStatus
		rus syscall.Rusage
	)
	for {
		pid, err := syscall.Wait4(-1, &ws, syscall.WNOHANG, &rus)
		if err != nil {
			if err == syscall.ECHILD {
				return exits, nil
			}
			return exits, err
		}
		if pid <= 0 {
			return exits, nil
		}
		exits = append(exits, Exit{
			Pid:    pid,
			Status: utils.ExitStatus(ws),
		})
	}
}