github.com/demonoid81/containerd@v1.3.4/sys/reaper.go (about) 1 // +build !windows 2 3 /* 4 Copyright The containerd Authors. 5 6 Licensed under the Apache License, Version 2.0 (the "License"); 7 you may not use this file except in compliance with the License. 8 You may obtain a copy of the License at 9 10 http://www.apache.org/licenses/LICENSE-2.0 11 12 Unless required by applicable law or agreed to in writing, software 13 distributed under the License is distributed on an "AS IS" BASIS, 14 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 See the License for the specific language governing permissions and 16 limitations under the License. 17 */ 18 19 package sys 20 21 import ( 22 "golang.org/x/sys/unix" 23 ) 24 25 // Exit is the wait4 information from an exited process 26 type Exit struct { 27 Pid int 28 Status int 29 } 30 31 // Reap reaps all child processes for the calling process and returns their 32 // exit information 33 func Reap(wait bool) (exits []Exit, err error) { 34 var ( 35 ws unix.WaitStatus 36 rus unix.Rusage 37 ) 38 flag := unix.WNOHANG 39 if wait { 40 flag = 0 41 } 42 for { 43 pid, err := unix.Wait4(-1, &ws, flag, &rus) 44 if err != nil { 45 if err == unix.ECHILD { 46 return exits, nil 47 } 48 return exits, err 49 } 50 if pid <= 0 { 51 return exits, nil 52 } 53 exits = append(exits, Exit{ 54 Pid: pid, 55 Status: exitStatus(ws), 56 }) 57 } 58 } 59 60 const exitSignalOffset = 128 61 62 // exitStatus returns the correct exit status for a process based on if it 63 // was signaled or exited cleanly 64 func exitStatus(status unix.WaitStatus) int { 65 if status.Signaled() { 66 return exitSignalOffset + int(status.Signal()) 67 } 68 return status.ExitStatus() 69 }