packer-cn/builder/parallels/common/host_ip_ifconfig.go

57 lines
1.3 KiB
Go

package common
import (
"bytes"
"errors"
"os"
"os/exec"
"regexp"
)
// IfconfigIPFinder finds the host IP based on the output of `ifconfig`.
type IfconfigIPFinder struct {
Devices []string
}
// HostIP returns the host's IP address or an error if it could not be found
// from the `ifconfig` output.
func (f *IfconfigIPFinder) HostIP() (string, error) {
var ifconfigPath string
// On some systems, ifconfig is in /sbin which is generally not
// on the PATH for a standard user, so we just check that first.
if _, err := os.Stat("/sbin/ifconfig"); err == nil {
ifconfigPath = "/sbin/ifconfig"
}
if ifconfigPath == "" {
var err error
ifconfigPath, err = exec.LookPath("ifconfig")
if err != nil {
return "", err
}
}
for _, device := range f.Devices {
stdout := new(bytes.Buffer)
cmd := exec.Command(ifconfigPath, device)
// Force LANG=C so that the output is what we expect it to be
// despite the locale.
cmd.Env = append(cmd.Env, "LANG=C")
cmd.Env = append(cmd.Env, os.Environ()...)
cmd.Stdout = stdout
cmd.Stderr = new(bytes.Buffer)
if err := cmd.Run(); err == nil {
re := regexp.MustCompile(`inet\s+(?:addr:)?(.+?)\s`)
matches := re.FindStringSubmatch(stdout.String())
if matches != nil {
return matches[1], nil
}
}
}
return "", errors.New("IP not found in ifconfig output")
}