setupapi: Make toUTF16() public and add UTF16ToBuf() counterpart

Signed-off-by: Simon Rozman <simon@rozman.si>

diff --git a/setupapi/setupapi_windows.go b/setupapi/setupapi_windows.go
index 84d324d79096f7e3cd389c821a536d710a3e3c5f..740b81bec120fbf9794d10fb794e02b56c444945 100644 (file)
--- a/setupapi/setupapi_windows.go
+++ b/setupapi/setupapi_windows.go
@@ -264,9 +264,9 @@ func SetupDiGetDeviceRegistryProperty(DeviceInfoSet DevInfo, DeviceInfoData *SP_
 func getRegistryValue(buf []byte, dataType uint32) (interface{}, error) {
        switch dataType {
        case windows.REG_SZ:
-               return windows.UTF16ToString(toUTF16(buf)), nil
+               return windows.UTF16ToString(BufToUTF16(buf)), nil
        case windows.REG_EXPAND_SZ:
-               return registry.ExpandString(windows.UTF16ToString(toUTF16(buf)))
+               return registry.ExpandString(windows.UTF16ToString(BufToUTF16(buf)))
        case windows.REG_BINARY:
                return buf, nil
        case windows.REG_DWORD_LITTLE_ENDIAN:
@@ -274,7 +274,7 @@ func getRegistryValue(buf []byte, dataType uint32) (interface{}, error) {
        case windows.REG_DWORD_BIG_ENDIAN:
                return binary.BigEndian.Uint32(buf), nil
        case windows.REG_MULTI_SZ:
-               bufW := toUTF16(buf)
+               bufW := BufToUTF16(buf)
                a := []string{}
                for i := 0; i < len(bufW); {
                        j := i + wcslen(bufW[i:])
@@ -291,7 +291,8 @@ func getRegistryValue(buf []byte, dataType uint32) (interface{}, error) {
        }
 }
 
-func toUTF16(buf []byte) []uint16 {
+// BufToUTF16 function reinterprets []byte buffer as []uint16
+func BufToUTF16(buf []byte) []uint16 {
        sl := struct {
                addr *uint16
                len  int
@@ -300,6 +301,16 @@ func toUTF16(buf []byte) []uint16 {
        return *(*[]uint16)(unsafe.Pointer(&sl))
 }
 
+// UTF16ToBuf function reinterprets []uint16 as []byte
+func UTF16ToBuf(buf []uint16) []byte {
+       sl := struct {
+               addr *byte
+               len  int
+               cap  int
+       }{(*byte)(unsafe.Pointer(&buf[0])), len(buf) * 2, cap(buf) * 2}
+       return *(*[]byte)(unsafe.Pointer(&sl))
+}
+
 func wcslen(str []uint16) int {
        for i := 0; i < len(str); i++ {
                if str[i] == 0 {

diff --git a/setupapi/setupapi_windows_test.go b/setupapi/setupapi_windows_test.go
index 12b5fe12f287967abea858191341a5b4b90bcb0f..3d9abd65a2ad068dc47d78f14b69dbf63c85cb81 100644 (file)
--- a/setupapi/setupapi_windows_test.go
+++ b/setupapi/setupapi_windows_test.go
@@ -403,3 +403,16 @@ func TestSetupDiGetSelectedDevice(t *testing.T) {
                }
        }
 }
+
+func TestUTF16ToBuf(t *testing.T) {
+       buf := []uint16{0x0123, 0x4567, 0x89ab, 0xcdef}
+       buf2 := UTF16ToBuf(buf)
+       if len(buf)*2 != len(buf2) ||
+               cap(buf)*2 != cap(buf2) ||
+               buf2[0] != 0x23 || buf2[1] != 0x01 ||
+               buf2[2] != 0x67 || buf2[3] != 0x45 ||
+               buf2[4] != 0xab || buf2[5] != 0x89 ||
+               buf2[6] != 0xef || buf2[7] != 0xcd {
+               t.Errorf("SetupDiSetSelectedDevice(nil) should fail with ERROR_INVALID_USER_BUFFER")
+       }
+}