Add vendor github.com/rs/xid

vendor/github.com/rs/xid/hostid_windows.go

@@ -0,0 +1,39 @@
+// +build windows
+
+package xid
+
+import (
+	"fmt"
+	"unsafe"
+
+	"golang.org/x/sys/windows"
+)
+
+func readPlatformMachineID() (string, error) {
+	// source: https://github.com/shirou/gopsutil/blob/master/host/host_windows.go
+	var h windows.Handle
+	err := windows.RegOpenKeyEx(windows.HKEY_LOCAL_MACHINE, windows.StringToUTF16Ptr(`SOFTWARE\Microsoft\Cryptography`), 0, windows.KEY_READ|windows.KEY_WOW64_64KEY, &h)
+	if err != nil {
+		return "", err
+	}
+	defer windows.RegCloseKey(h)
+
+	const windowsRegBufLen = 74 // len(`{`) + len(`abcdefgh-1234-456789012-123345456671` * 2) + len(`}`) // 2 == bytes/UTF16
+	const uuidLen = 36
+
+	var regBuf [windowsRegBufLen]uint16
+	bufLen := uint32(windowsRegBufLen)
+	var valType uint32
+	err = windows.RegQueryValueEx(h, windows.StringToUTF16Ptr(`MachineGuid`), nil, &valType, (*byte)(unsafe.Pointer(&regBuf[0])), &bufLen)
+	if err != nil {
+		return "", err
+	}
+
+	hostID := windows.UTF16ToString(regBuf[:])
+	hostIDLen := len(hostID)
+	if hostIDLen != uuidLen {
+		return "", fmt.Errorf("HostID incorrect: %q\n", hostID)
+	}
+
+	return hostID, nil
+}