dbus: Add GetUnitByPID

dbus/methods.go

@@ -288,6 +288,15 @@ func (c *Conn) listUnitsInternal(f storeFunc) ([]UnitStatus, error) {
  return status, nil
 }
 
+// GetUnitByPID returns an array with all currently loaded units. Note that
+func (c *Conn) GetUnitByPID(pid int) (dbus.ObjectPath, error) {
+ var op dbus.ObjectPath
+ if err := c.sysobj.Call("org.freedesktop.systemd1.Manager.GetUnitByPID", 0, uint(pid)).Store(&op); err != nil {
+ return dbus.ObjectPath(""), err
+ }
+ return op, nil
+}
+
 // ListUnits returns an array with all currently loaded units. Note that
 // units may be known by multiple names at the same time, and hence there might
 // be more unit names loaded than actual units behind them.

dbus/methods_test.go

@@ -16,11 +16,14 @@ package dbus
 
 import (
  "fmt"
+ "io/ioutil"
+ "log"
  "os"
  "os/exec"
  "path"
  "path/filepath"
  "reflect"
+ "strconv"
  "syscall"
  "testing"
  "time"
@@ -132,6 +135,18 @@ func runStopUnit(t *testing.T, conn *Conn, trTarget TrUnitProp) error {
  return nil
 }
 
+func assertNoError(t *testing.T, err error) {
+ if err != nil {
+ t.Fatal(err)
+ }
+}
+
+func assertEqualStr(t *testing.T, shouldBe, target string) {
+ if target != shouldBe {
+ t.Fatalf("expected %q to equal %q", target, shouldBe)
+ }
+}
+
 // Ensure that basic unit starting and stopping works.
 func TestStartStopUnit(t *testing.T) {
  target := "start-stop.service"
@@ -1539,3 +1554,31 @@ func TestUnitName(t *testing.T) {
  }
  }
 }
+
+func TestGetUnitByPID(t *testing.T) {
+ target := "get-unit-pid.service"
+ conn := setupConn(t)
+ defer conn.Close()
+
+ setupUnit(target, conn, t)
+ linkUnit(target, conn, t)
+
+ reschan := make(chan string)
+ _, err := conn.StartUnit(target, "replace", reschan)
+ assertNoError(t, err)
+
+ job := <-reschan
+ if job != "done" {
+ t.Fatal("Job is not done:", job)
+ }
+
+ pidStr, err := ioutil.ReadFile("../fixtures/get-unit-pid.pid")
+ assertNoError(t, err)
+ pid, err := strconv.Atoi(string(pidStr))
+ assertNoError(t, err)
+ objectPath, err := conn.GetUnitByPID(pid)
+ if err != nil {
+ log.Fatalf("conn.getunitbypid ntp: %v", err)
+ }
+ assertEqualStr(t, "foo", string(objectPath))
+}

fixtures/get-unit-pid.service

@@ -0,0 +1,5 @@
+[Unit]
+Description=get unit pid
+
+[Service]
+ExecStart=get-unit-pid.sh

fixtures/get-unit-pid.sh

@@ -0,0 +1,2 @@
+/bin/echo ${PID} >get-unit-pid.pid
+/bin/sleep 400