getSerialPortsWindows.go

//go:build windows

package main

import (
	"syscall"
	"errors"
  "golang.org/x/sys/windows"
  "unsafe"
)

var (
  modadvapi32 = windows.NewLazySystemDLL("advapi32.dll")
  procRegEnumValueW       = modadvapi32.NewProc("RegEnumValueW")
)

func regEnumValue(key syscall.Handle, index uint32, name *uint16, nameLen *uint32, reserved *uint32, class *uint16, value *uint16, valueLen *uint32) (regerrno error) {
	r0, _, _ := syscall.Syscall9(procRegEnumValueW.Addr(), 8, uintptr(key), uintptr(index), uintptr(unsafe.Pointer(name)), uintptr(unsafe.Pointer(nameLen)), uintptr(unsafe.Pointer(reserved)), uintptr(unsafe.Pointer(class)), uintptr(unsafe.Pointer(value)), uintptr(unsafe.Pointer(valueLen)), 0)
	if r0 != 0 {
		regerrno = syscall.Errno(r0)
	}
	return
}


func nativeGetPortsList() ([]string, error) {
	subKey, err := syscall.UTF16PtrFromString("HARDWARE\\DEVICEMAP\\SERIALCOMM\\")
	if err != nil {
		return nil, errors.New("ErrorEnumeratingPorts")
	}

	var h syscall.Handle
	if err := syscall.RegOpenKeyEx(syscall.HKEY_LOCAL_MACHINE, subKey, 0, syscall.KEY_READ, &h); err != nil {
		if errno, isErrno := err.(syscall.Errno); isErrno && errno == syscall.ERROR_FILE_NOT_FOUND {
			return []string{}, nil
		}
		return nil, errors.New("ErrorEnumeratingPorts")
	}
	defer syscall.RegCloseKey(h)

	var valuesCount uint32
	if syscall.RegQueryInfoKey(h, nil, nil, nil, nil, nil, nil, &valuesCount, nil, nil, nil, nil) != nil {
		return nil, errors.New("ErrorEnumeratingPorts")
	}

	list := make([]string, valuesCount)
	for i := range list {
		var data [1024]uint16
		dataSize := uint32(len(data))
		var name [1024]uint16
		nameSize := uint32(len(name))
		if regEnumValue(h, uint32(i), &name[0], &nameSize, nil, nil, &data[0], &dataSize) != nil {
      return nil, errors.New("ErrorEnumeratingPorts")
		}
		list[i] = syscall.UTF16ToString(data[:])
	}
	return list, nil
}