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

WinAPI operations

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

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
-	LpMaximumApplicationAddress *byte
-	DwActiveProcessorMask       *uint32
+	LpMinimumApplicationAddress uintptr
+	LpMaximumApplicationAddress uintptr
+	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) {
-	var mse MemoryStatusEx
+func GlobalMemoryStatusEx() (MemoryStatus, error) {
+	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 MemoryStatusEx{}, err
+		return MemoryStatus{}, 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 {
-	var info LpSystemInfo
+func GetSystemInfo() SystemInfo {
+	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