pdh: fall back to localized names of v2 counter sets (#2709)

Signed-off-by: Claude <noreply@anthropic.com>
Signed-off-by: Jan-Otto Kröpke <mail@jkroepke.de>
Co-authored-by: Claude <noreply@anthropic.com>

internal/pdh/localized_internal_test.go

@@ -0,0 +1,116 @@
+// 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.
+
+//go:build windows
+
+package pdh
+
+import (
+	"encoding/binary"
+	"testing"
+	"unicode/utf16"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestUTF16String(t *testing.T) {
+	buf := utf16Bytes("SMB-Serverfreigaben")
+	buf = append(buf, 'x', 0)
+
+	require.Equal(t, "SMB-Serverfreigaben", utf16String(buf))
+	require.Empty(t, utf16String(nil))
+}
+
+// TestEnglishCounterSets checks the English names of a v2 counter set that
+// every supported Windows version registers. Classic sets like Processor
+// Information are not v2 counter sets.
+func TestEnglishCounterSets(t *testing.T) {
+	guid, ok := englishCounterSets()["smb client shares"]
+	require.True(t, ok, "SMB Client Shares counter set not found")
+
+	names := counterNames(&guid, langIDEnglish)
+	require.Contains(t, mapValues(names), "Avg. sec/Read")
+}
+
+// TestLocalizedCounterPaths checks that an English path maps to the counter
+// set's names in the UI language. On an English system, there is nothing to map.
+func TestLocalizedCounterPaths(t *testing.T) {
+	paths := localizedCounterPaths("SMB Client Shares", "*", "Avg. sec/Read")
+
+	for _, langID := range uiLanguages() {
+		if isEnglish(langID) {
+			continue
+		}
+
+		require.NotEmpty(t, paths, "no localized path for UI language %#x", langID)
+	}
+
+	for _, path := range paths {
+		var query pdhQueryHandle
+
+		require.Equal(t, uint32(ErrorSuccess), OpenQuery(0, 0, &query))
+
+		var counter pdhCounterHandle
+
+		ret := AddCounter(query, path, 0, &counter)
+		CloseQuery(query)
+
+		require.Equal(t, uint32(ErrorSuccess), ret, "add localized counter %s", path)
+	}
+}
+
+func mapValues(m map[uint32]string) []string {
+	values := make([]string, 0, len(m))
+	for _, v := range m {
+		values = append(values, v)
+	}
+
+	return values
+}
+
+func utf16Bytes(s string) []byte {
+	chars := utf16.Encode([]rune(s))
+	buf := make([]byte, 0, 2*len(chars)+2)
+
+	for _, c := range chars {
+		buf = binary.LittleEndian.AppendUint16(buf, c)
+	}
+
+	return binary.LittleEndian.AppendUint16(buf, 0)
+}
+
+func TestCounterNamesBuffer(t *testing.T) {
+	first := utf16Bytes("Anzahl derzeit geöffneter Dateien")
+	second := utf16Bytes("Anzahl von Strukturverbindungen")
+
+	// PERF_STRING_BUFFER_HEADER, three PERF_STRING_COUNTER_HEADERs, strings.
+	const headers = 8 + 3*8
+
+	buf := binary.LittleEndian.AppendUint32(nil, uint32(headers+len(first)+len(second)))
+	buf = binary.LittleEndian.AppendUint32(buf, 3)
+	buf = binary.LittleEndian.AppendUint32(buf, 1)
+	buf = binary.LittleEndian.AppendUint32(buf, headers)
+	buf = binary.LittleEndian.AppendUint32(buf, 2)
+	buf = binary.LittleEndian.AppendUint32(buf, uint32(headers+len(first)))
+	buf = binary.LittleEndian.AppendUint32(buf, 3)
+	buf = binary.LittleEndian.AppendUint32(buf, 0xFFFFFFFF)
+	buf = append(buf, first...)
+	buf = append(buf, second...)
+
+	require.Equal(t, map[uint32]string{
+		1: "Anzahl derzeit geöffneter Dateien",
+		2: "Anzahl von Strukturverbindungen",
+	}, parseCounterNames(buf))
+}