Fix missing vendor dir

vendor/github.com/shirou/gopsutil/mem/mem_windows.go

@@ -0,0 +1,165 @@
+// +build windows
+
+package mem
+
+import (
+	"context"
+	"sync"
+	"syscall"
+	"unsafe"
+
+	"github.com/shirou/gopsutil/internal/common"
+	"golang.org/x/sys/windows"
+)
+
+var (
+	procEnumPageFilesW       = common.ModPsapi.NewProc("EnumPageFilesW")
+	procGetNativeSystemInfo  = common.Modkernel32.NewProc("GetNativeSystemInfo")
+	procGetPerformanceInfo   = common.ModPsapi.NewProc("GetPerformanceInfo")
+	procGlobalMemoryStatusEx = common.Modkernel32.NewProc("GlobalMemoryStatusEx")
+)
+
+type memoryStatusEx struct {
+	cbSize                  uint32
+	dwMemoryLoad            uint32
+	ullTotalPhys            uint64 // in bytes
+	ullAvailPhys            uint64
+	ullTotalPageFile        uint64
+	ullAvailPageFile        uint64
+	ullTotalVirtual         uint64
+	ullAvailVirtual         uint64
+	ullAvailExtendedVirtual uint64
+}
+
+func VirtualMemory() (*VirtualMemoryStat, error) {
+	return VirtualMemoryWithContext(context.Background())
+}
+
+func VirtualMemoryWithContext(ctx context.Context) (*VirtualMemoryStat, error) {
+	var memInfo memoryStatusEx
+	memInfo.cbSize = uint32(unsafe.Sizeof(memInfo))
+	mem, _, _ := procGlobalMemoryStatusEx.Call(uintptr(unsafe.Pointer(&memInfo)))
+	if mem == 0 {
+		return nil, windows.GetLastError()
+	}
+
+	ret := &VirtualMemoryStat{
+		Total:       memInfo.ullTotalPhys,
+		Available:   memInfo.ullAvailPhys,
+		Free:        memInfo.ullAvailPhys,
+		UsedPercent: float64(memInfo.dwMemoryLoad),
+	}
+
+	ret.Used = ret.Total - ret.Available
+	return ret, nil
+}
+
+type performanceInformation struct {
+	cb                uint32
+	commitTotal       uint64
+	commitLimit       uint64
+	commitPeak        uint64
+	physicalTotal     uint64
+	physicalAvailable uint64
+	systemCache       uint64
+	kernelTotal       uint64
+	kernelPaged       uint64
+	kernelNonpaged    uint64
+	pageSize          uint64
+	handleCount       uint32
+	processCount      uint32
+	threadCount       uint32
+}
+
+func SwapMemory() (*SwapMemoryStat, error) {
+	return SwapMemoryWithContext(context.Background())
+}
+
+func SwapMemoryWithContext(ctx context.Context) (*SwapMemoryStat, error) {
+	var perfInfo performanceInformation
+	perfInfo.cb = uint32(unsafe.Sizeof(perfInfo))
+	mem, _, _ := procGetPerformanceInfo.Call(uintptr(unsafe.Pointer(&perfInfo)), uintptr(perfInfo.cb))
+	if mem == 0 {
+		return nil, windows.GetLastError()
+	}
+	tot := perfInfo.commitLimit * perfInfo.pageSize
+	used := perfInfo.commitTotal * perfInfo.pageSize
+	free := tot - used
+	var usedPercent float64
+	if tot == 0 {
+		usedPercent = 0
+	} else {
+		usedPercent = float64(used) / float64(tot) * 100
+	}
+	ret := &SwapMemoryStat{
+		Total:       tot,
+		Used:        used,
+		Free:        free,
+		UsedPercent: usedPercent,
+	}
+
+	return ret, nil
+}
+
+var (
+	pageSize     uint64
+	pageSizeOnce sync.Once
+)
+
+type systemInfo struct {
+	wProcessorArchitecture      uint16
+	wReserved                   uint16
+	dwPageSize                  uint32
+	lpMinimumApplicationAddress uintptr
+	lpMaximumApplicationAddress uintptr
+	dwActiveProcessorMask       uintptr
+	dwNumberOfProcessors        uint32
+	dwProcessorType             uint32
+	dwAllocationGranularity     uint32
+	wProcessorLevel             uint16
+	wProcessorRevision          uint16
+}
+
+// system type as defined in https://docs.microsoft.com/en-us/windows/win32/api/psapi/ns-psapi-enum_page_file_information
+type enumPageFileInformation struct {
+	cb         uint32
+	reserved   uint32
+	totalSize  uint64
+	totalInUse uint64
+	peakUsage  uint64
+}
+
+func SwapDevices() ([]*SwapDevice, error) {
+	return SwapDevicesWithContext(context.Background())
+}
+
+func SwapDevicesWithContext(ctx context.Context) ([]*SwapDevice, error) {
+	pageSizeOnce.Do(func() {
+		var sysInfo systemInfo
+		procGetNativeSystemInfo.Call(uintptr(unsafe.Pointer(&sysInfo)))
+		pageSize = uint64(sysInfo.dwPageSize)
+	})
+
+	// the following system call invokes the supplied callback function once for each page file before returning
+	// see https://docs.microsoft.com/en-us/windows/win32/api/psapi/nf-psapi-enumpagefilesw
+	var swapDevices []*SwapDevice
+	result, _, _ := procEnumPageFilesW.Call(windows.NewCallback(pEnumPageFileCallbackW), uintptr(unsafe.Pointer(&swapDevices)))
+	if result == 0 {
+		return nil, windows.GetLastError()
+	}
+
+	return swapDevices, nil
+}
+
+// system callback as defined in https://docs.microsoft.com/en-us/windows/win32/api/psapi/nc-psapi-penum_page_file_callbackw
+func pEnumPageFileCallbackW(swapDevices *[]*SwapDevice, enumPageFileInfo *enumPageFileInformation, lpFilenamePtr *[syscall.MAX_LONG_PATH]uint16) *bool {
+	*swapDevices = append(*swapDevices, &SwapDevice{
+		Name:      syscall.UTF16ToString((*lpFilenamePtr)[:]),
+		UsedBytes: enumPageFileInfo.totalInUse * pageSize,
+		FreeBytes: (enumPageFileInfo.totalSize - enumPageFileInfo.totalInUse) * pageSize,
+	})
+
+	// return true to continue enumerating page files
+	ret := true
+	return &ret
+}