gpu: add device id label (#2186)

internal/headers/win32/types.go

@@ -18,6 +18,7 @@
 package win32
 
 import (
+	"strconv"
 	"unsafe"
 
 	"golang.org/x/sys/windows"
@@ -32,8 +33,8 @@ type (
 	LPWSTR    struct {
 		*uint16
 	}
-	ULONG = uint32 // ULONG is a 32-bit unsigned int in Win32
-	UINT  = uint32 // UINT is a 32-bit unsigned int in Win32
+	ULONG uint32 // ULONG is a 32-bit unsigned int in Win32
+	UINT  uint32 // UINT is a 32-bit unsigned int in Win32
 )
 
 // NewLPWSTR creates a new LPWSTR from a string.
@@ -60,3 +61,7 @@ func (s *LPWSTR) Pointer() uintptr {
 func (s *LPWSTR) String() string {
 	return windows.UTF16PtrToString(s.uint16)
 }
+
+func (u *UINT) String() string {
+	return strconv.FormatUint(uint64(*u), 10)
+}

internal/headers/win32/utils.go

@@ -0,0 +1,55 @@
+// SPDX-License-Identifier: Apache-2.0
+//
+// Copyright The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package win32
+
+// ParseMultiSz splits a UTF-16 encoded MULTI_SZ buffer (Windows style) into
+// individual UTF-16 string slices.
+//
+// A MULTI_SZ buffer is a sequence of UTF-16 strings separated by single null
+// terminators (0x0000) and terminated by an extra null (i.e., two consecutive
+// nulls) to mark the end of the list.
+//
+// Example layout in memory (UTF-16):
+//
+//	"foo\0bar\0baz\0\0"
+//
+// Given such a []uint16, this function returns a [][]uint16 where each inner
+// slice is one null-terminated string segment without the trailing null.
+//
+// The returned slices reference the original buffer (no copying).
+func ParseMultiSz(buf []uint16) [][]uint16 {
+	var (
+		result [][]uint16
+		start  int
+	)
+
+	for i := range buf {
+		if buf[i] == 0 {
+			// Found a null terminator.
+			if i == start {
+				// Two consecutive nulls → end of list.
+				break
+			}
+
+			// Append current string slice (excluding null).
+			result = append(result, buf[start:i])
+			// Move start to next character after null.
+			start = i + 1
+		}
+	}
+
+	return result
+}