moby/pkg/system/exitcode.go

package system

import (
	"fmt"
	"os/exec"
	"syscall"
)

// GetExitCode returns the ExitStatus of the specified error if its type is
// exec.ExitError, returns 0 and an error otherwise.
func GetExitCode(err error) (int, error) {
	exitCode := 0
	if exiterr, ok := err.(*exec.ExitError); ok {
		if procExit, ok := exiterr.Sys().(syscall.WaitStatus); ok {
			return procExit.ExitStatus(), nil
		}
	}
	return exitCode, fmt.Errorf("failed to get exit code")
}

// ProcessExitCode process the specified error and returns the exit status code
// if the error was of type exec.ExitError, returns nothing otherwise.
func ProcessExitCode(err error) (exitCode int) {
	if err != nil {
		var exiterr error
		if exitCode, exiterr = GetExitCode(err); exiterr != nil {
			// TODO: Fix this so we check the error's text.
			// we've failed to retrieve exit code, so we set it to 127
			exitCode = 127
		}
	}
	return
}