test/2398-method-trace-opt-code/src/VMDebug.java

/*
 * Copyright (C) 2025 The Android Open Source Project
 *
 * 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.
 */

import java.io.File;
import java.io.FileDescriptor;
import java.io.FileOutputStream;
import java.io.IOException;
import java.lang.reflect.Method;

public class VMDebug {
    private static final String TEMP_FILE_NAME_PREFIX = "test";
    private static final String TEMP_FILE_NAME_SUFFIX = ".trace";
    private static final Method startMethodTracingMethod;
    private static final Method stopMethodTracingMethod;
    private static final Method getMethodTracingModeMethod;

    static {
        try {
            Class<?> c = Class.forName("dalvik.system.VMDebug");
            startMethodTracingMethod = c.getDeclaredMethod(
                    "startMethodTracing", String.class, FileDescriptor.class, Integer.TYPE,
                    Integer.TYPE, Boolean.TYPE, Integer.TYPE, Boolean.TYPE);
            stopMethodTracingMethod = c.getDeclaredMethod("stopMethodTracing");
            getMethodTracingModeMethod = c.getDeclaredMethod("getMethodTracingMode");
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    public static void startMethodTracing(String filename, FileDescriptor fd, int bufferSize,
                                          int flags, boolean samplingEnabled, int intervalUs,
                                          boolean streaming) throws Exception {
        startMethodTracingMethod.invoke(null, filename, fd, bufferSize, flags, samplingEnabled,
                                        intervalUs, streaming);
    }

    public static void $noinline$stopMethodTracing() throws Exception {
        stopMethodTracingMethod.invoke(null);
    }

    public static int getMethodTracingMode() throws Exception {
        return (int) getMethodTracingModeMethod.invoke(null);
    }

    public static File createTempFile() throws Exception {
        try {
            return File.createTempFile(TEMP_FILE_NAME_PREFIX, TEMP_FILE_NAME_SUFFIX);
        } catch (IOException e) {
            System.setProperty("java.io.tmpdir", "/data/local/tmp");
            try {
                return File.createTempFile(TEMP_FILE_NAME_PREFIX, TEMP_FILE_NAME_SUFFIX);
            } catch (IOException e2) {
                System.setProperty("java.io.tmpdir", "/sdcard");
                return File.createTempFile(TEMP_FILE_NAME_PREFIX, TEMP_FILE_NAME_SUFFIX);
            }
        }
    }
}