blob: 289044a44d4b21665ffdfc080765c8d47028bd68 [file] [log] [blame]
// +build !darwin
package dbus
import (
"bytes"
"errors"
"fmt"
"io/ioutil"
"os"
"os/exec"
"os/user"
"path"
"strings"
)
func getSessionBusPlatformAddress() (string, error) {
cmd := exec.Command("dbus-launch")
b, err := cmd.CombinedOutput()
if err != nil {
return "", err
}
i := bytes.IndexByte(b, '=')
j := bytes.IndexByte(b, '\n')
if i == -1 || j == -1 {
return "", errors.New("dbus: couldn't determine address of session bus")
}
env, addr := string(b[0:i]), string(b[i+1:j])
os.Setenv(env, addr)
return addr, nil
}
// tryDiscoverDbusSessionBusAddress tries to discover an existing dbus session
// and return the value of its DBUS_SESSION_BUS_ADDRESS.
// It tries different techniques employed by different operating systems,
// returning the first valid address it finds, or an empty string.
//
// * /run/user/<uid>/bus if this exists, it *is* the bus socket. present on
// Ubuntu 18.04
// * /run/user/<uid>/dbus-session: if this exists, it can be parsed for the bus
// address. present on Ubuntu 16.04
//
// See https://dbus.freedesktop.org/doc/dbus-launch.1.html
func tryDiscoverDbusSessionBusAddress() string {
if runtimeDirectory, err := getRuntimeDirectory(); err == nil {
if runUserBusFile := path.Join(runtimeDirectory, "bus"); fileExists(runUserBusFile) {
// if /run/user/<uid>/bus exists, that file itself
// *is* the unix socket, so return its path
return fmt.Sprintf("unix:path=%s", runUserBusFile)
}
if runUserSessionDbusFile := path.Join(runtimeDirectory, "dbus-session"); fileExists(runUserSessionDbusFile) {
// if /run/user/<uid>/dbus-session exists, it's a
// text file // containing the address of the socket, e.g.:
// DBUS_SESSION_BUS_ADDRESS=unix:abstract=/tmp/dbus-E1c73yNqrG
if f, err := ioutil.ReadFile(runUserSessionDbusFile); err == nil {
fileContent := string(f)
prefix := "DBUS_SESSION_BUS_ADDRESS="
if strings.HasPrefix(fileContent, prefix) {
address := strings.TrimRight(strings.TrimPrefix(fileContent, prefix), "\n\r")
return address
}
}
}
}
return ""
}
func getRuntimeDirectory() (string, error) {
if currentUser, err := user.Current(); err != nil {
return "", err
} else {
return fmt.Sprintf("/run/user/%s", currentUser.Uid), nil
}
}
func fileExists(filename string) bool {
if _, err := os.Stat(filename); !os.IsNotExist(err) {
return true
} else {
return false
}
}