/*

 * Copyright (c) 2013, 2018, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package org.graalvm.compiler.core.test;

import static org.graalvm.compiler.serviceprovider.GraalServices.Java8OrEarlier;

import java.lang.annotation.Annotation;

import org.graalvm.compiler.nodes.Invoke;

import org.graalvm.compiler.nodes.StructuredGraph;

import org.graalvm.compiler.nodes.java.MethodCallTargetNode;

import org.graalvm.compiler.phases.VerifyPhase;

import org.graalvm.compiler.phases.tiers.PhaseContext;

import jdk.vm.ci.meta.ResolvedJavaMethod;

import jdk.vm.ci.meta.ResolvedJavaType;

/**

 * Verifies a method is annotated with CallerSensitive iff it calls Reflection#getCallerClass().

 */

public class VerifyCallerSensitiveMethods extends VerifyPhase<PhaseContext> {

    Class<? extends Annotation> callerSensitiveClass;

    Class<?> reflectionClass;

    @Override

    public boolean checkContract() {

        return false;

    }

    @SuppressWarnings("unchecked")

    public VerifyCallerSensitiveMethods() {

        try {

            ClassLoader classLoader = ClassLoader.getSystemClassLoader();

            if (Java8OrEarlier) {

                reflectionClass = classLoader.loadClass("sun.reflect.Reflection");

                callerSensitiveClass = (Class<? extends Annotation>) classLoader.loadClass("sun.reflect.ConstantPool");

            } else {

                reflectionClass = classLoader.loadClass("jdk.internal.reflect.Reflection");

                callerSensitiveClass = (Class<? extends Annotation>) classLoader.loadClass("jdk.internal.reflect.ConstantPool");

            }

        } catch (ClassNotFoundException e) {

            throw new AssertionError(e);

        }

    }

    @Override

    protected boolean verify(StructuredGraph graph, PhaseContext context) {

        Invoke invoke = callsReflectionGetCallerClass(graph, context);

        Annotation annotation = graph.method().getAnnotation(callerSensitiveClass);

        if (invoke != null) {

            if (annotation == null) {

                StackTraceElement e = graph.method().asStackTraceElement(invoke.bci());

                throw new VerificationError(String.format("%s: method that calls Reflection.getCallerClass() must be annotated with @CallerSensitive", e));

            }

        } else if (annotation != null) {

            throw new VerificationError(String.format("%s: method annotated with @CallerSensitive does not call Reflection.getCallerClass()", graph.method().format("%H.%n(%p)")));

        }

        return true;

    }

    private Invoke callsReflectionGetCallerClass(StructuredGraph graph, PhaseContext context) {

        ResolvedJavaType reflectionType = context.getMetaAccess().lookupJavaType(reflectionClass);

        for (MethodCallTargetNode t : graph.getNodes(MethodCallTargetNode.TYPE)) {

            ResolvedJavaMethod callee = t.targetMethod();

            if (callee.getDeclaringClass().equals(reflectionType)) {

                if (callee.getName().equals("getCallerClass")) {

                    return t.invoke();

                }

            }

        }

        return null;

    }

}