broker leak detector

broker-leak-detector/pom.xml

@@ -0,0 +1,74 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+ xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+ xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+ <modelVersion>4.0.0</modelVersion>
+
+ <groupId>org.existdb</groupId>
+ <artifactId>broker-leak-detector</artifactId>
+ <version>1.0-SNAPSHOT</version>
+
+ <dependencies>
+ <dependency>
+ <groupId>org.kohsuke</groupId>
+ <artifactId>asm5</artifactId>
+ <version>5.0.1</version>
+ </dependency>
+
+ <dependency>
+ <groupId>args4j</groupId>
+ <artifactId>args4j</artifactId>
+ <version>2.0.16</version>
+ </dependency>
+ </dependencies>
+
+ <build>
+ <plugins>
+ <plugin>
+ <artifactId>maven-compiler-plugin</artifactId>
+ <configuration>
+ <source>1.5</source>
+ <target>1.5</target>
+ </configuration>
+ </plugin>
+ <plugin>
+ <artifactId>maven-shade-plugin</artifactId>
+ <executions>
+ <execution>
+ <goals>
+ <goal>shade</goal>
+ </goals>
+ <phase>package</phase>
+ <configuration>
+ <shadedArtifactAttached>true</shadedArtifactAttached>
+ <shadedClassifierName>jar-with-dependencies</shadedClassifierName>
+ <transformers>
+ <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
+ <manifestEntries>
+ <Agent-Class>org.exist.agent.AgentMain</Agent-Class>
+ <Premain-Class>org.exist.agent.AgentMain</Premain-Class>
+ <Main-Class>org.exist.agent.Main</Main-Class>
+ <Can-Retransform-Classes>true</Can-Retransform-Classes>
+ <Can-Redefine-Classes>true</Can-Redefine-Classes>
+ </manifestEntries>
+ </transformer>
+ </transformers>
+ <relocations>
+ <relocation>
+ <pattern>org.kohsuke.args4j</pattern>
+ <shadedPattern>org.exist.agent.args4j</shadedPattern>
+ </relocation>
+ <relocation>
+ <pattern>org.kohsuke.asm3</pattern>
+ <shadedPattern>org.exist.agent.asm3</shadedPattern>
+ </relocation>
+ </relocations>
+ </configuration>
+ </execution>
+ </executions>
+ <configuration>
+ </configuration>
+ </plugin>
+ </plugins>
+ </build>
+</project>

broker-leak-detector/src/main/java/org/exist/agent/AgentMain.java

@@ -0,0 +1,149 @@
+package org.exist.agent;
+
+import org.exist.agent.transform.ClassTransformSpec;
+import org.exist.agent.transform.CodeGenerator;
+import org.exist.agent.transform.MethodAppender;
+import org.exist.agent.transform.TransformerImpl;
+
+import java.io.*;
+import java.lang.instrument.Instrumentation;
+import java.net.InetSocketAddress;
+import java.net.ServerSocket;
+import java.net.Socket;
+import java.util.Arrays;
+import java.util.List;
+import java.util.concurrent.Callable;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ThreadFactory;
+
+/**
+ * @author <a href="mailto:[email protected]">Dmitriy Shabanov</a>
+ */
+public class AgentMain {
+
+
+ public static void premain(String arguments, Instrumentation instrumentation) throws Exception {
+
+ int port = 12251;
+
+ if (arguments != null) {
+ for (String argument : arguments.split(",")) {
+ if (argument.startsWith("http=")) {
+ port = Integer.parseInt(argument.substring(argument.indexOf('=') + 1));
+ }
+ }
+ }
+
+ System.err.println("eXist-db agent installed");
+
+ instrumentation.addTransformer(new TransformerImpl(createSpec()),true);
+
+ //instrumentation.retransformClasses(...class);
+
+ runHttpServer(port);
+ }
+
+ private static void runHttpServer(int port) throws IOException {
+ final ServerSocket ss = new ServerSocket();
+ ss.bind(new InetSocketAddress("localhost", port));
+ System.err.println("Serving broker leak info on http://localhost:"+port+"/");
+ final ExecutorService es = Executors.newCachedThreadPool(new ThreadFactory() {
+ public Thread newThread(Runnable r) {
+ Thread t = new Thread(r);
+ t.setDaemon(true);
+ return t;
+ }
+ });
+ es.submit(new Callable<Void>() {
+ public Void call() throws Exception {
+ while (true) {
+ final Socket s = ss.accept();
+ es.submit(new Callable<Void>() {
+ public Void call() throws Exception {
+ try {
+ BufferedReader in = new BufferedReader(new InputStreamReader(s.getInputStream()));
+ // Read the request line (and ignore it)
+ in.readLine();
+
+ PrintWriter w = new PrintWriter(new OutputStreamWriter(s.getOutputStream(), "UTF-8"));
+ w.print("HTTP/1.0 200 OK\r\nContent-Type: text/plain;charset=UTF-8\r\n\r\n");
+ Listener.dump(w);
+ } finally {
+ s.close();
+ }
+ return null;
+ }
+ });
+ }
+ }
+ });
+ }
+
+
+ static List<ClassTransformSpec> createSpec() {
+ return Arrays.asList(
+ new ClassTransformSpec("org/exist/storage/DBBroker",
+ new OccupationInterceptor(),
+ new ReleaseInterceptor(),
+ new Skip("<init>", "*"),
+ new Skip("<clinit>", "*"),
+ new Skip("initIndexModules", "*"),
+ new Skip("addContentLoadingObserver", "*"),
+ new Skip("clearContentLoadingObservers", "*"),
+ new Skip("setId", "*"),
+ new CheckerInterceptor()
+ )
+ );
+ }
+
+
+ private static class OccupationInterceptor extends MethodAppender {
+ OccupationInterceptor() {
+ super("incReferenceCount", "()V", false);
+ }
+
+ @Override
+ protected void append(CodeGenerator g) {
+ g.invokeAppStatic(Listener.class,"occupation",
+ new Class[]{Object.class},
+ new int[]{0});
+ }
+ }
+
+ private static class ReleaseInterceptor extends MethodAppender {
+ ReleaseInterceptor() {
+ super("decReferenceCount", "()V", false);
+ }
+
+ @Override
+ protected void append(CodeGenerator g) {
+ g.invokeAppStatic(Listener.class,"release",
+ new Class[]{Object.class},
+ new int[]{0});
+ }
+ }
+
+ private static class CheckerInterceptor extends MethodAppender {
+ CheckerInterceptor() {
+ super("*", "", false);
+ }
+
+ @Override
+ protected void append(CodeGenerator g) {
+ g.invokeAppStatic(Listener.class,"check",
+ new Class[]{Object.class},
+ new int[]{0});
+ }
+ }
+
+ private static class Skip extends MethodAppender {
+ Skip(String name, String signature) {
+ super(name, signature, true);
+ }
+
+ @Override
+ protected void append(CodeGenerator g) {
+ }
+ }
+}