Add idiomatic wrappers to be exposed publically, and hide low-level

WinAPI operations

Signed-off-by: Ben Ridley <benridley29@gmail.com>

collector/cs.go

@@ -72,13 +72,13 @@ func (c *CSCollector) collect(ch chan<- prometheus.Metric) (*prometheus.Desc, er
 	ch <- prometheus.MustNewConstMetric(
 		c.LogicalProcessors,
 		prometheus.GaugeValue,
-		float64(systemInfo.DwNumberOfProcessors),
+		float64(systemInfo.NumberOfProcessors),
 	)
 
 	ch <- prometheus.MustNewConstMetric(
 		c.PhysicalMemoryBytes,
 		prometheus.GaugeValue,
-		float64(mem.UllTotalPhys),
+		float64(mem.TotalPhys),
 	)
 
 	hostname, err := sysinfoapi.GetComputerName(sysinfoapi.ComputerNameDNSHostname)

collector/os.go

@@ -158,7 +158,7 @@ type Win32_OperatingSystem struct {
 }
 
 func (c *OSCollector) collect(ctx *ScrapeContext, ch chan<- prometheus.Metric) (*prometheus.Desc, error) {
-	nwgi, _, err := netapi32.NetWkstaGetInfo()
+	nwgi, err := netapi32.GetWorkstationInfo()
 	if err != nil {
 		return nil, err
 	}
@@ -241,13 +241,13 @@ func (c *OSCollector) collect(ctx *ScrapeContext, ch chan<- prometheus.Metric) (
 		prometheus.GaugeValue,
 		1.0,
 		fmt.Sprintf("Microsoft %s", pn), // Caption
-		fmt.Sprintf("%d.%d.%s", nwgi.Wki102_ver_major, nwgi.Wki102_ver_minor, bn), // Version
+		fmt.Sprintf("%d.%d.%s", nwgi.VersionMajor, nwgi.VersionMinor, bn), // Version
 	)
 
 	ch <- prometheus.MustNewConstMetric(
 		c.PhysicalMemoryFreeBytes,
 		prometheus.GaugeValue,
-		float64(gmse.UllAvailPhys),
+		float64(gmse.AvailPhys),
 	)
 
 	ch <- prometheus.MustNewConstMetric(
@@ -272,7 +272,7 @@ func (c *OSCollector) collect(ctx *ScrapeContext, ch chan<- prometheus.Metric) (
 	ch <- prometheus.MustNewConstMetric(
 		c.VirtualMemoryFreeBytes,
 		prometheus.GaugeValue,
-		float64(gmse.UllAvailPageFile),
+		float64(gmse.AvailPageFile),
 	)
 
 	// Windows has no defined limit, and is based off available resources. This currently isn't calculated by WMI and is set to default value.
@@ -287,7 +287,7 @@ func (c *OSCollector) collect(ctx *ScrapeContext, ch chan<- prometheus.Metric) (
 	ch <- prometheus.MustNewConstMetric(
 		c.ProcessMemoryLimitBytes,
 		prometheus.GaugeValue,
-		float64(gmse.UllTotalVirtual),
+		float64(gmse.TotalVirtual),
 	)
 
 	ch <- prometheus.MustNewConstMetric(
@@ -299,7 +299,7 @@ func (c *OSCollector) collect(ctx *ScrapeContext, ch chan<- prometheus.Metric) (
 	ch <- prometheus.MustNewConstMetric(
 		c.Users,
 		prometheus.GaugeValue,
-		float64(nwgi.Wki102_logged_on_users),
+		float64(nwgi.LoggedOnUsers),
 	)
 
 	ch <- prometheus.MustNewConstMetric(
@@ -311,13 +311,13 @@ func (c *OSCollector) collect(ctx *ScrapeContext, ch chan<- prometheus.Metric) (
 	ch <- prometheus.MustNewConstMetric(
 		c.VirtualMemoryBytes,
 		prometheus.GaugeValue,
-		float64(gmse.UllTotalPageFile),
+		float64(gmse.TotalPageFile),
 	)
 
 	ch <- prometheus.MustNewConstMetric(
 		c.VisibleMemoryBytes,
 		prometheus.GaugeValue,
-		float64(gmse.UllTotalPhys),
+		float64(gmse.TotalPhys),
 	)
 
 	return nil, nil

headers/netapi32/netapi32.go

@@ -9,14 +9,25 @@ import (
 
 // WKSTAInfo102 is a wrapper of WKSTA_Info_102
 //https://docs.microsoft.com/en-us/windows/win32/api/lmwksta/ns-lmwksta-wksta_info_102
-type WKSTAInfo102 struct {
+type wKSTAInfo102 struct {
-	Wki102_platform_id     uint32
+	wki102_platform_id     uint32
 	wki102_computername    *uint16
 	wki102_langroup        *uint16
-	Wki102_ver_major       uint32
+	wki102_ver_major       uint32
-	Wki102_ver_minor       uint32
+	wki102_ver_minor       uint32
 	wki102_lanroot         *uint16
-	Wki102_logged_on_users uint32
+	wki102_logged_on_users uint32
+}
+
+// WorkstationInfo is an idiomatic wrapper of WKSTAInfo102
+type WorkstationInfo struct {
+	PlatformId    uint32
+	ComputerName  string
+	LanGroup      string
+	VersionMajor  uint32
+	VersionMinor  uint32
+	LanRoot       string
+	LoggedOnUsers uint32
 }
 
 var (
@@ -57,33 +68,42 @@ var NetApiStatus = map[uint32]string{
 
 // NetApiBufferFree frees the memory other network management functions use internally to return information.
 // https://docs.microsoft.com/en-us/windows/win32/api/lmapibuf/nf-lmapibuf-netapibufferfree
-func NetApiBufferFree(buffer *WKSTAInfo102) {
+func netApiBufferFree(buffer *wKSTAInfo102) {
 	procNetApiBufferFree.Call(uintptr(unsafe.Pointer(buffer)))
 }
 
 // NetWkstaGetInfo returns information about the configuration of a workstation.
+// WARNING: The caller must call netApiBufferFree to free the memory allocated by this function.
 // https://docs.microsoft.com/en-us/windows/win32/api/lmwksta/nf-lmwksta-netwkstagetinfo
-func NetWkstaGetInfo() (WKSTAInfo102, uint32, error) {
+func netWkstaGetInfo() (*wKSTAInfo102, uint32, error) {
-	// Struct
+	var lpwi *wKSTAInfo102
-	var lpwi *WKSTAInfo102
-	pLpwi := uintptr(unsafe.Pointer(&lpwi))
-
-	// Null value
-	var nullptr = uintptr(0)
-
-	// Level
 	pLevel := uintptr(102)
 
-	// Func call
+	r1, _, _ := procNetWkstaGetInfo.Call(0, pLevel, uintptr(unsafe.Pointer(&lpwi)))
-	r1, _, _ := procNetWkstaGetInfo.Call(nullptr, pLevel, pLpwi)
 
 	if ret := *(*uint32)(unsafe.Pointer(&r1)); ret != 0 {
-		return WKSTAInfo102{}, ret, errors.New(NetApiStatus[ret])
+		return nil, ret, errors.New(NetApiStatus[ret])
 	}
 
-	// Derence the pointer and return the object so we can safely clear the buffer.
+	return lpwi, 0, nil
-	var deref WKSTAInfo102 = *lpwi
+}
-	defer NetApiBufferFree(lpwi)
+
-
+// GetWorkstationInfo is an idiomatic wrapper for netWkstaGetInfo
-	return deref, 0, nil
+func GetWorkstationInfo() (WorkstationInfo, error) {
+	info, _, err := netWkstaGetInfo()
+	if err != nil {
+		return WorkstationInfo{}, err
+	}
+	workstationInfo := WorkstationInfo{
+		PlatformId:    info.wki102_platform_id,
+		ComputerName:  windows.UTF16PtrToString(info.wki102_computername),
+		LanGroup:      windows.UTF16PtrToString(info.wki102_langroup),
+		VersionMajor:  info.wki102_ver_major,
+		VersionMinor:  info.wki102_ver_minor,
+		LanRoot:       windows.UTF16PtrToString(info.wki102_lanroot),
+		LoggedOnUsers: info.wki102_logged_on_users,
+	}
+	// Free the memory allocated by netapi
+	netApiBufferFree(info)
+	return workstationInfo, nil
 }

headers/sysinfoapi/sysinfoapi.go

@@ -1,6 +1,7 @@
 package sysinfoapi
 
 import (
+	"fmt"
 	"unicode/utf16"
 	"unsafe"
 
@@ -9,7 +10,7 @@ import (
 
 // MemoryStatusEx is a wrapper for MEMORYSTATUSEX
 // https://docs.microsoft.com/en-us/windows/win32/api/sysinfoapi/ns-sysinfoapi-memorystatusex
-type MemoryStatusEx struct {
+type memoryStatusEx struct {
 	dwLength                uint32
 	DwMemoryLoad            uint32
 	UllTotalPhys            uint64
@@ -21,6 +22,18 @@ type MemoryStatusEx struct {
 	UllAvailExtendedVirtual uint64
 }
 
+// MemoryStatus is an idiomatic wrapper for MemoryStatusEx
+type MemoryStatus struct {
+	MemoryLoad           uint32
+	TotalPhys            uint64
+	AvailPhys            uint64
+	TotalPageFile        uint64
+	AvailPageFile        uint64
+	TotalVirtual         uint64
+	AvailVirtual         uint64
+	AvailExtendedVirtual uint64
+}
+
 // wProcessorArchitecture is a wrapper for the union found in LP_SYSTEM_INFO
 // https://docs.microsoft.com/en-us/windows/win32/api/sysinfoapi/ns-sysinfoapi-system_info
 type wProcessorArchitecture struct {
@@ -28,14 +41,27 @@ type wProcessorArchitecture struct {
 	WProcessorArchitecture uint16
 }
 
+// ProcessorArchitecture is an idiomatic wrapper for wProcessorArchitecture
+type ProcessorArchitecture uint16
+
+// Idiomatic values for wProcessorArchitecture
+const (
+	AMD64   ProcessorArchitecture = 9
+	ARM                           = 5
+	ARM64                         = 12
+	IA64                          = 6
+	INTEL                         = 0
+	UNKNOWN                       = 0xffff
+)
+
 // LpSystemInfo is a wrapper for LPSYSTEM_INFO
 // https://docs.microsoft.com/en-us/windows/win32/api/sysinfoapi/ns-sysinfoapi-system_info
-type LpSystemInfo struct {
+type lpSystemInfo struct {
 	Arch                        wProcessorArchitecture
 	DwPageSize                  uint32
-	LpMinimumApplicationAddress *byte
+	LpMinimumApplicationAddress uintptr
-	LpMaximumApplicationAddress *byte
+	LpMaximumApplicationAddress uintptr
-	DwActiveProcessorMask       *uint32
+	DwActiveProcessorMask       uint32
 	DwNumberOfProcessors        uint32
 	DwProcessorType             uint32
 	DwAllocationGranularity     uint32
@@ -43,6 +69,20 @@ type LpSystemInfo struct {
 	WProcessorRevision          uint16
 }
 
+// SystemInfo is an idiomatic wrapper for LpSystemInfo
+type SystemInfo struct {
+	Arch                      ProcessorArchitecture
+	PageSize                  uint32
+	MinimumApplicationAddress uintptr
+	MaximumApplicationAddress uintptr
+	ActiveProcessorMask       uint32
+	NumberOfProcessors        uint32
+	ProcessorType             uint32
+	AllocationGranularity     uint32
+	ProcessorLevel            uint16
+	ProcessorRevision         uint16
+}
+
 // WinComputerNameFormat is a wrapper for COMPUTER_NAME_FORMAT
 type WinComputerNameFormat int
 
@@ -68,27 +108,47 @@ var (
 
 // GlobalMemoryStatusEx retrieves information about the system's current usage of both physical and virtual memory.
 // https://docs.microsoft.com/en-us/windows/win32/api/sysinfoapi/nf-sysinfoapi-globalmemorystatusex
-func GlobalMemoryStatusEx() (MemoryStatusEx, error) {
+func GlobalMemoryStatusEx() (MemoryStatus, error) {
-	var mse MemoryStatusEx
+	var mse memoryStatusEx
 	mse.dwLength = (uint32)(unsafe.Sizeof(mse))
 	pMse := uintptr(unsafe.Pointer(&mse))
 	r1, _, err := procGlobalMemoryStatusEx.Call(pMse)
 
 	if ret := *(*bool)(unsafe.Pointer(&r1)); ret == false {
-		// returned false
+		return MemoryStatus{}, err
-		return MemoryStatusEx{}, err
 	}
 
-	return mse, nil
+	return MemoryStatus{
+		MemoryLoad:           mse.DwMemoryLoad,
+		TotalPhys:            mse.UllTotalPhys,
+		AvailPhys:            mse.UllAvailPhys,
+		TotalPageFile:        mse.UllTotalPageFile,
+		AvailPageFile:        mse.UllAvailPageFile,
+		TotalVirtual:         mse.UllTotalVirtual,
+		AvailVirtual:         mse.UllAvailVirtual,
+		AvailExtendedVirtual: mse.UllAvailExtendedVirtual,
+	}, nil
 }
 
 // GetSystemInfo wraps the GetSystemInfo function from sysinfoapi
 // https://docs.microsoft.com/en-us/windows/win32/api/sysinfoapi/nf-sysinfoapi-getsysteminfo
-func GetSystemInfo() LpSystemInfo {
+func GetSystemInfo() SystemInfo {
-	var info LpSystemInfo
+	var info lpSystemInfo
 	pInfo := uintptr(unsafe.Pointer(&info))
 	procGetSystemInfo.Call(pInfo)
-	return info
+	fmt.Printf("%+v", info)
+	return SystemInfo{
+		Arch:                      ProcessorArchitecture(info.Arch.WProcessorArchitecture),
+		PageSize:                  info.DwPageSize,
+		MinimumApplicationAddress: info.LpMinimumApplicationAddress,
+		MaximumApplicationAddress: info.LpMinimumApplicationAddress,
+		ActiveProcessorMask:       info.DwActiveProcessorMask,
+		NumberOfProcessors:        info.DwNumberOfProcessors,
+		ProcessorType:             info.DwProcessorType,
+		AllocationGranularity:     info.DwAllocationGranularity,
+		ProcessorLevel:            info.WProcessorLevel,
+		ProcessorRevision:         info.WProcessorRevision,
+	}
 }
 
 // GetComputerName wraps the GetComputerNameW function in a more Go-like way