mirror of
https://github.com/linuxkit/linuxkit.git
synced 2025-10-25 14:47:35 +00:00
c92af038fb
This is an example external logging service which can be enabled by
adding it to the `init` section of the .yml, for example:
...
init:
- linuxkit/init:35866bb276c264a5f664bfac7456f4b9eeb87a4d
- linuxkit/runc:v0.4
- linuxkit/containerd:f2bc1bda1ab18146967fa1a149800aaf14bee81b
- linuxkit/ca-certificates:v0.4
- linuxkit/memlogd:cc035e5c9e4011ec1ba97a181a6689fc90965ce9
onboot:
...
Signed-off-by: David Scott <dave.scott@docker.com>
77 lines
2.1 KiB
Go
77 lines
2.1 KiB
Go
package main
|
|
|
|
import (
|
|
"flag"
|
|
"fmt"
|
|
"log"
|
|
"net"
|
|
"os"
|
|
"os/exec"
|
|
"syscall"
|
|
)
|
|
|
|
func main() {
|
|
var socketLogPath string
|
|
var socketQueryPath string
|
|
var memlogdBundle string
|
|
var pidFile string
|
|
var detach bool
|
|
flag.StringVar(&socketLogPath, "socket-log", "/var/run/linuxkit-external-logging.sock", "path to fd logging socket. Created and passed to logging container. Existing socket will be removed.")
|
|
flag.StringVar(&socketQueryPath, "socket-query", "/var/run/memlogdq.sock", "path to query socket. Created and passed to logging container. Existing socket will be removed.")
|
|
flag.StringVar(&memlogdBundle, "bundle", "/containers/init/memlogd", "runc bundle with memlogd")
|
|
flag.StringVar(&pidFile, "pid-file", "/run/memlogd.pid", "path to pid file")
|
|
flag.BoolVar(&detach, "detach", true, "detach from subprocess")
|
|
flag.Parse()
|
|
|
|
laddr := net.UnixAddr{socketLogPath, "unixgram"}
|
|
os.Remove(laddr.Name) // remove existing socket
|
|
lconn, err := net.ListenUnixgram("unixgram", &laddr)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
lfd, err := lconn.File()
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
|
|
qaddr := net.UnixAddr{socketQueryPath, "unix"}
|
|
os.Remove(qaddr.Name) // remove existing socket
|
|
qconn, err := net.ListenUnix("unix", &qaddr)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
qfd, err := qconn.File()
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
|
|
cmd := exec.Command("/sbin/start-stop-daemon", "--start", "--pidfile", pidFile,
|
|
"--exec", "/usr/bin/runc", "--", "run", "--preserve-fds=2",
|
|
"--bundle", memlogdBundle,
|
|
"--pid-file", pidFile, "memlogd")
|
|
log.Println(cmd.Args)
|
|
cmd.ExtraFiles = append(cmd.ExtraFiles, lfd, qfd)
|
|
cmd.Stdout = os.Stdout
|
|
cmd.Stderr = os.Stderr
|
|
if err := cmd.Start(); err != nil {
|
|
panic(err)
|
|
}
|
|
if detach {
|
|
if err := cmd.Process.Release(); err != nil {
|
|
panic(err)
|
|
}
|
|
} else {
|
|
if err := cmd.Wait(); err != nil {
|
|
if exitError, ok := err.(*exec.ExitError); ok {
|
|
// exit with exit code from process
|
|
status := exitError.Sys().(syscall.WaitStatus)
|
|
os.Exit(status.ExitStatus())
|
|
} else {
|
|
// no exit code, report error and exit 1
|
|
fmt.Println(err)
|
|
os.Exit(1)
|
|
}
|
|
}
|
|
}
|
|
}
|