Update gosigar windows code to use gosigar/sys/windows package

- Fixes elastic#53 (ProcStatus.PPID value is wrong on Windows). The code was incorrectly using `CreateToolhelp32Snapshot` + `Process32First`. This could have been fixed, but it would have required iterating over each process until finding the PPID of process we were interested it. Instead the code has been changed to use `NtQueryInformationProcess` to get the PPID given a process token.
- Fixes elastic#6 (Get the cpu usage per core in Windows). I used `NtQuerySystemInformation` to collect the timing information on a per CPU basis.
- Adds OS version checks to the functions that make certain WMI calls. The `Win32_Process` data is only available on Vista and newer. On XP and Win2003, these methods will return `ErrNotImplemented`. This will help address elastic/beats#1704.
- Implements `Uptime.Get` for Windows.
- Implements `Swap.Get` for Windows based on page file metrics.
- Removes cgo usage for Windows.
- Adds support to `github.com/gosigar/sys/windows` for querying and enabling privileges in a process token. This will help in addressing elastic/beats#1897.

CHANGELOG.md

@@ -5,14 +5,28 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 ## [Unreleased]
 
 ### Added
+- Added `CpuList` implementation for Windows that returns CPU timing information
+  on a per CPU basis. #55
+- Added `Uptime` implementation for Windows. #55
+- Added `Swap` implementation for Windows based on page file metrics. #55
+- Added support to `github.com/gosigar/sys/windows` for querying and enabling
+  privileges in a process token.
 
 ### Changed
-- Changed several `OpenProcess` calls on Windows to request the lowest possible access privilege. #50
+- Changed several `OpenProcess` calls on Windows to request the lowest possible
+  access privileges. #50
+- Removed cgo usage from Windows code.
+
+- Added OS version checks to `ProcArgs.Get` on Windows because the
+  `Win32_Process` WMI query is not available prior to Windows vista. On XP and
+  Windows 2003, this method returns `ErrNotImplemented`. #55
 
 ### Deprecated
 
 ### Removed
 
 ### Fixed
-- Fix value of `Mem.ActualFree` and `Mem.ActualUsed` on Windows. #49
-- Fix `ProcTime.StartTime` on Windows to report value in milliseconds since Unix epoch. #51
+- Fixed value of `Mem.ActualFree` and `Mem.ActualUsed` on Windows. #49
+- Fixed `ProcTime.StartTime` on Windows to report value in milliseconds since
+  Unix epoch. #51
+- Fixed #53 ProcStatus.PPID value is wrong on Windows. #55

concrete_sigar_test.go

@@ -35,6 +35,7 @@ func TestConcreteCollectCpuStats(t *testing.T) {
 func TestConcreteGetLoadAverage(t *testing.T) {
 	concreteSigar := &sigar.ConcreteSigar{}
 	avg, err := concreteSigar.GetLoadAverage()
+	skipNotImplemented(t, err, "windows")
 	if assert.NoError(t, err) {
 		assert.NotNil(t, avg.One)
 		assert.NotNil(t, avg.Five)
@@ -78,10 +79,7 @@ func TestConcreteFileSystemUsage(t *testing.T) {
 func TestConcreteGetFDUsage(t *testing.T) {
 	concreteSigar := &sigar.ConcreteSigar{}
 	fdUsage, err := concreteSigar.GetFDUsage()
-	// if it's not implemented, don't test
-	if _, ok := err.(sigar.ErrNotImplemented); ok {
-		t.Skipf("Skipping *ConcreteSigar.GetFDUsage test because it is not implemented for " + runtime.GOOS)
-	}
+	skipNotImplemented(t, err, "windows")
 	if assert.NoError(t, err) {
 		assert.True(t, fdUsage.Open > 0)
 		assert.True(t, fdUsage.Open <= fdUsage.Max)

sigar_interface_test.go

@@ -21,11 +21,10 @@ func TestCpu(t *testing.T) {
 
 func TestLoadAverage(t *testing.T) {
 	avg := LoadAverage{}
-	assert.NoError(t, avg.Get())
+	assert.NoError(t, skipNotImplemented(t, avg.Get(), "windows"))
 }
 
 func TestUptime(t *testing.T) {
-	skipWindows(t)
 	uptime := Uptime{}
 	if assert.NoError(t, uptime.Get()) {
 		assert.True(t, uptime.Length > 0, "Uptime (%f) must be positive", uptime.Length)
@@ -52,27 +51,26 @@ func TestSwap(t *testing.T) {
 }
 
 func TestCpuList(t *testing.T) {
-	skipWindows(t)
-	cpulist := CpuList{}
-	if assert.NoError(t, cpulist.Get()) {
-		numCore := len(cpulist.List)
+	cpuList := CpuList{}
+	if assert.NoError(t, cpuList.Get()) {
+		numCore := len(cpuList.List)
 		numCpu := runtime.NumCPU()
 		assert.True(t, numCore >= numCpu, "Number of cores (%d) >= number of logical CPUs (%d)",
 			numCore, numCpu)
 	}
 }
 
 func TestFileSystemList(t *testing.T) {
-	fslist := FileSystemList{}
-	if assert.NoError(t, fslist.Get()) {
-		assert.True(t, len(fslist.List) > 0)
+	fsList := FileSystemList{}
+	if assert.NoError(t, fsList.Get()) {
+		assert.True(t, len(fsList.List) > 0)
 	}
 }
 
 func TestFileSystemUsage(t *testing.T) {
 	root := "/"
 	if runtime.GOOS == "windows" {
-		root = "C:\\"
+		root = `C:\`
 	}
 	fsusage := FileSystemUsage{}
 	if assert.NoError(t, fsusage.Get(root)) {
@@ -99,6 +97,7 @@ func TestProcState(t *testing.T) {
 		assert.Contains(t, []RunState{RunStateRun, RunStateSleep}, state.State)
 		assert.Regexp(t, "go(.exe)?", state.Name)
 		assert.Equal(t, u.Username, state.Username)
+		assert.True(t, state.Ppid > 0, "ppid=%v is non-positive", state.Ppid)
 	}
 
 	assert.Error(t, state.Get(invalidPid))
@@ -123,23 +122,31 @@ func TestProcTime(t *testing.T) {
 }
 
 func TestProcArgs(t *testing.T) {
-	skipWindows(t)
 	args := ProcArgs{}
 	if assert.NoError(t, args.Get(os.Getppid())) {
-		assert.True(t, len(args.List) >= 2)
+		assert.NotEmpty(t, args.List)
 	}
 }
 
 func TestProcExe(t *testing.T) {
-	skipWindows(t)
 	exe := ProcExe{}
-	if assert.NoError(t, exe.Get(os.Getppid())) {
+	if assert.NoError(t, skipNotImplemented(t, exe.Get(os.Getppid()), "windows")) {
 		assert.Regexp(t, "go(.exe)?", filepath.Base(exe.Name))
 	}
 }
 
-func skipWindows(t testing.TB) {
-	if runtime.GOOS == "windows" {
-		t.Skipf("Skipping test on %s", runtime.GOOS)
+func skipNotImplemented(t testing.TB, err error, goos ...string) error {
+	for _, os := range goos {
+		if runtime.GOOS == os {
+			if err == nil {
+				t.Fatal("expected ErrNotImplemented")
+			} else if IsNotImplemented(err) {
+				t.Skipf("Skipping test on %s", runtime.GOOS)
+			}
+
+			break
+		}
 	}
+
+	return err
 }