From 069016bbc4fac01260f2addd70b67bce5ebeac70 Mon Sep 17 00:00:00 2001
From: Simon Rozman <simon@rozman.si>
Date: Wed, 6 Feb 2019 20:17:47 +0100
Subject: [PATCH] setupapi: Add SP_DRVINFO_DATA.IsNewer() method to simplify
 comparison

Signed-off-by: Simon Rozman <simon@rozman.si>
---
 setupapi/setupapi_windows_test.go | 22 ++++++++++++++++++++++
 setupapi/types_windows.go         | 26 ++++++++++++++++++++++++++
 2 files changed, 48 insertions(+)

diff --git a/setupapi/setupapi_windows_test.go b/setupapi/setupapi_windows_test.go
index 3d9abd6..9f45a6f 100644
--- a/setupapi/setupapi_windows_test.go
+++ b/setupapi/setupapi_windows_test.go
@@ -177,6 +177,28 @@ func TestDevInfo_BuildDriverInfoList(t *testing.T) {
 				continue
 			}
 
+			if !driverData.IsNewer(windows.Filetime{}, 0) {
+				t.Error("Driver should have non-zero date and version")
+			}
+			if !driverData.IsNewer(windows.Filetime{HighDateTime: driverData.DriverDate.HighDateTime}, 0) {
+				t.Error("Driver should have non-zero date and version")
+			}
+			if driverData.IsNewer(windows.Filetime{HighDateTime: driverData.DriverDate.HighDateTime + 1}, 0) {
+				t.Error("Driver should report newer version on high-date-time")
+			}
+			if !driverData.IsNewer(windows.Filetime{HighDateTime: driverData.DriverDate.HighDateTime, LowDateTime: driverData.DriverDate.LowDateTime}, 0) {
+				t.Error("Driver should have non-zero version")
+			}
+			if driverData.IsNewer(windows.Filetime{HighDateTime: driverData.DriverDate.HighDateTime, LowDateTime: driverData.DriverDate.LowDateTime + 1}, 0) {
+				t.Error("Driver should report newer version on low-date-time")
+			}
+			if driverData.IsNewer(windows.Filetime{HighDateTime: driverData.DriverDate.HighDateTime, LowDateTime: driverData.DriverDate.LowDateTime}, driverData.DriverVersion) {
+				t.Error("Driver should not be newer than itself")
+			}
+			if driverData.IsNewer(windows.Filetime{HighDateTime: driverData.DriverDate.HighDateTime, LowDateTime: driverData.DriverDate.LowDateTime}, driverData.DriverVersion+1) {
+				t.Error("Driver should report newer version on version")
+			}
+
 			err = devInfoList.SetSelectedDriver(deviceData, driverData)
 			if err != nil {
 				t.Errorf("Error calling SetupDiSetSelectedDriver: %s", err.Error())
diff --git a/setupapi/types_windows.go b/setupapi/types_windows.go
index 0eb640c..2dfcb70 100644
--- a/setupapi/types_windows.go
+++ b/setupapi/types_windows.go
@@ -321,6 +321,32 @@ func (data SP_DRVINFO_DATA) ToGo() *DrvInfoData {
 	}
 }
 
+// IsNewer method returns true if SP_DRVINFO_DATA date and version is newer than supplied parameters.
+func (data SP_DRVINFO_DATA) IsNewer(DriverDate windows.Filetime, DriverVersion uint64) bool {
+	if data.DriverDate.HighDateTime > DriverDate.HighDateTime {
+		return true
+	}
+	if data.DriverDate.HighDateTime < DriverDate.HighDateTime {
+		return false
+	}
+
+	if data.DriverDate.LowDateTime > DriverDate.LowDateTime {
+		return true
+	}
+	if data.DriverDate.LowDateTime < DriverDate.LowDateTime {
+		return false
+	}
+
+	if data.DriverVersion > DriverVersion {
+		return true
+	}
+	if data.DriverVersion < DriverVersion {
+		return false
+	}
+
+	return false
+}
+
 // DrvInfoData is driver information structure (member of a driver info list that may be associated with a particular device instance, or (globally) with a device information set)
 type DrvInfoData struct {
 	DriverType    uint32