Merge pull request #762 from Lomanic/issue760

[process] Fix #760 implement IsRunning by checking process with same PID has same CreateTime as current process

process/process.go

@@ -31,6 +31,7 @@ type Process struct {
 	numThreads     int32
 	memInfo        *MemoryInfoStat
 	sigInfo        *SignalInfoStat
+	createTime     int64
 
 	lastCPUTimes *cpu.TimesStat
 	lastCPUTime  time.Time
@@ -163,6 +164,7 @@ func NewProcess(pid int32) (*Process, error) {
 	if !exists {
 		return p, ErrorProcessNotRunning
 	}
+	go p.CreateTime()
 	return p, nil
 }
 
@@ -222,6 +224,41 @@ func (p *Process) PercentWithContext(ctx context.Context, interval time.Duration
 	return ret, nil
 }
 
+// IsRunning returns whether the process is still running or not.
+func (p *Process) IsRunning() (bool, error) {
+	return p.IsRunningWithContext(context.Background())
+}
+
+func (p *Process) IsRunningWithContext(ctx context.Context) (bool, error) {
+	createTime, err := p.CreateTimeWithContext(ctx)
+	if err != nil {
+		return false, err
+	}
+	p2, err := NewProcess(p.Pid)
+	if err == ErrorProcessNotRunning {
+		return false, nil
+	}
+	createTime2, err := p2.CreateTimeWithContext(ctx)
+	if err != nil {
+		return false, err
+	}
+	return createTime == createTime2, nil
+}
+
+// CreateTime returns created time of the process in milliseconds since the epoch, in UTC.
+func (p *Process) CreateTime() (int64, error) {
+	return p.CreateTimeWithContext(context.Background())
+}
+
+func (p *Process) CreateTimeWithContext(ctx context.Context) (int64, error) {
+	if p.createTime != 0 {
+		return p.createTime, nil
+	}
+	createTime, err := p.createTimeWithContext(ctx)
+	p.createTime = createTime
+	return p.createTime, err
+}
+
 func calculatePercent(t1, t2 *cpu.TimesStat, delta float64, numcpu int) float64 {
 	if delta == 0 {
 		return 0

process/process_darwin.go

@@ -129,11 +129,8 @@ func (p *Process) CmdlineSliceWithContext(ctx context.Context) ([]string, error)
 	}
 	return r[0], err
 }
-func (p *Process) CreateTime() (int64, error) {
-	return p.CreateTimeWithContext(context.Background())
-}
 
-func (p *Process) CreateTimeWithContext(ctx context.Context) (int64, error) {
+func (p *Process) createTimeWithContext(ctx context.Context) (int64, error) {
 	r, err := callPsWithContext(ctx, "etime", p.Pid, false)
 	if err != nil {
 		return 0, err
@@ -527,13 +524,6 @@ func (p *Process) NetIOCountersWithContext(ctx context.Context, pernic bool) ([]
 	return nil, common.ErrNotImplementedError
 }
 
-func (p *Process) IsRunning() (bool, error) {
-	return p.IsRunningWithContext(context.Background())
-}
-
-func (p *Process) IsRunningWithContext(ctx context.Context) (bool, error) {
-	return true, common.ErrNotImplementedError
-}
 func (p *Process) MemoryMaps(grouped bool) (*[]MemoryMapsStat, error) {
 	return p.MemoryMapsWithContext(context.Background(), grouped)
 }

process/process_fallback.go

@@ -93,11 +93,8 @@ func (p *Process) CmdlineSlice() ([]string, error) {
 func (p *Process) CmdlineSliceWithContext(ctx context.Context) ([]string, error) {
 	return []string{}, common.ErrNotImplementedError
 }
-func (p *Process) CreateTime() (int64, error) {
-	return p.CreateTimeWithContext(context.Background())
-}
 
-func (p *Process) CreateTimeWithContext(ctx context.Context) (int64, error) {
+func (p *Process) createTimeWithContext(ctx context.Context) (int64, error) {
 	return 0, common.ErrNotImplementedError
 }
 func (p *Process) Cwd() (string, error) {
@@ -283,13 +280,7 @@ func (p *Process) NetIOCounters(pernic bool) ([]net.IOCountersStat, error) {
 func (p *Process) NetIOCountersWithContext(ctx context.Context, pernic bool) ([]net.IOCountersStat, error) {
 	return []net.IOCountersStat{}, common.ErrNotImplementedError
 }
-func (p *Process) IsRunning() (bool, error) {
-	return p.IsRunningWithContext(context.Background())
-}
 
-func (p *Process) IsRunningWithContext(ctx context.Context) (bool, error) {
-	return true, common.ErrNotImplementedError
-}
 func (p *Process) MemoryMaps(grouped bool) (*[]MemoryMapsStat, error) {
 	return p.MemoryMapsWithContext(context.Background(), grouped)
 }

process/process_freebsd.go

@@ -116,11 +116,8 @@ func (p *Process) CmdlineSliceWithContext(ctx context.Context) ([]string, error)
 
 	return strParts, nil
 }
-func (p *Process) CreateTime() (int64, error) {
-	return p.CreateTimeWithContext(context.Background())
-}
 
-func (p *Process) CreateTimeWithContext(ctx context.Context) (int64, error) {
+func (p *Process) createTimeWithContext(ctx context.Context) (int64, error) {
 	return 0, common.ErrNotImplementedError
 }
 func (p *Process) Cwd() (string, error) {
@@ -428,13 +425,6 @@ func (p *Process) NetIOCountersWithContext(ctx context.Context, pernic bool) ([]
 	return nil, common.ErrNotImplementedError
 }
 
-func (p *Process) IsRunning() (bool, error) {
-	return p.IsRunningWithContext(context.Background())
-}
-
-func (p *Process) IsRunningWithContext(ctx context.Context) (bool, error) {
-	return true, common.ErrNotImplementedError
-}
 func (p *Process) MemoryMaps(grouped bool) (*[]MemoryMapsStat, error) {
 	return p.MemoryMapsWithContext(context.Background(), grouped)
 }

process/process_linux.go

@@ -130,12 +130,7 @@ func (p *Process) CmdlineSliceWithContext(ctx context.Context) ([]string, error)
 	return p.fillSliceFromCmdlineWithContext(ctx)
 }
 
-// CreateTime returns created time of the process in milliseconds since the epoch, in UTC.
+func (p *Process) createTimeWithContext(ctx context.Context) (int64, error) {
-func (p *Process) CreateTime() (int64, error) {
-	return p.CreateTimeWithContext(context.Background())
-}
-
-func (p *Process) CreateTimeWithContext(ctx context.Context) (int64, error) {
 	_, _, _, createTime, _, _, _, err := p.fillFromStatWithContext(ctx)
 	if err != nil {
 		return 0, err
@@ -550,16 +545,6 @@ func (p *Process) NetIOCountersWithContext(ctx context.Context, pernic bool) ([]
 	return net.IOCountersByFile(pernic, filename)
 }
 
-// IsRunning returns whether the process is running or not.
-// Not implemented yet.
-func (p *Process) IsRunning() (bool, error) {
-	return p.IsRunningWithContext(context.Background())
-}
-
-func (p *Process) IsRunningWithContext(ctx context.Context) (bool, error) {
-	return true, common.ErrNotImplementedError
-}
-
 // MemoryMaps get memory maps from /proc/(pid)/smaps
 func (p *Process) MemoryMaps(grouped bool) (*[]MemoryMapsStat, error) {
 	return p.MemoryMapsWithContext(context.Background(), grouped)

process/process_openbsd.go

@@ -114,11 +114,7 @@ func (p *Process) CmdlineWithContext(ctx context.Context) (string, error) {
 	return strings.Join(argv, " "), nil
 }
 
-func (p *Process) CreateTime() (int64, error) {
+func (p *Process) createTimeWithContext(ctx context.Context) (int64, error) {
-	return p.CreateTimeWithContext(context.Background())
-}
-
-func (p *Process) CreateTimeWithContext(ctx context.Context) (int64, error) {
 	return 0, common.ErrNotImplementedError
 }
 func (p *Process) Cwd() (string, error) {
@@ -415,13 +411,6 @@ func (p *Process) NetIOCountersWithContext(ctx context.Context, pernic bool) ([]
 	return nil, common.ErrNotImplementedError
 }
 
-func (p *Process) IsRunning() (bool, error) {
-	return p.IsRunningWithContext(context.Background())
-}
-
-func (p *Process) IsRunningWithContext(ctx context.Context) (bool, error) {
-	return true, common.ErrNotImplementedError
-}
 func (p *Process) MemoryMaps(grouped bool) (*[]MemoryMapsStat, error) {
 	return p.MemoryMapsWithContext(context.Background(), grouped)
 }

process/process_test.go

@@ -539,3 +539,30 @@ func Test_Kill(t *testing.T) {
 	assert.Nil(t, err)
 	cmd.Wait()
 }
+
+func Test_IsRunning(t *testing.T) {
+	var cmd *exec.Cmd
+	if runtime.GOOS == "windows" {
+		cmd = exec.Command("ping", "localhost", "-n", "2")
+	} else {
+		cmd = exec.Command("sleep", "1")
+	}
+	cmd.Start()
+	p, err := NewProcess(int32(cmd.Process.Pid))
+	assert.Nil(t, err)
+	running, err := p.IsRunning()
+	if err != nil {
+		t.Fatalf("IsRunning error: %v", err)
+	}
+	if !running {
+		t.Fatalf("process should be found running")
+	}
+	cmd.Wait()
+	running, err = p.IsRunning()
+	if err != nil {
+		t.Fatalf("IsRunning error: %v", err)
+	}
+	if running {
+		t.Fatalf("process should NOT be found running")
+	}
+}

process/process_windows.go

@@ -320,11 +320,7 @@ func (p *Process) CmdlineSliceWithContext(ctx context.Context) ([]string, error)
 	return strings.Split(cmdline, " "), nil
 }
 
-func (p *Process) CreateTime() (int64, error) {
+func (p *Process) createTimeWithContext(ctx context.Context) (int64, error) {
-	return p.CreateTimeWithContext(context.Background())
-}
-
-func (p *Process) CreateTimeWithContext(ctx context.Context) (int64, error) {
 	ru, err := getRusage(p.Pid)
 	if err != nil {
 		return 0, fmt.Errorf("could not get CreationDate: %s", err)
@@ -659,14 +655,6 @@ func (p *Process) NetIOCountersWithContext(ctx context.Context, pernic bool) ([]
 	return nil, common.ErrNotImplementedError
 }
 
-func (p *Process) IsRunning() (bool, error) {
-	return p.IsRunningWithContext(context.Background())
-}
-
-func (p *Process) IsRunningWithContext(ctx context.Context) (bool, error) {
-	return true, common.ErrNotImplementedError
-}
-
 func (p *Process) MemoryMaps(grouped bool) (*[]MemoryMapsStat, error) {
 	return p.MemoryMapsWithContext(context.Background(), grouped)
 }