/*

 * Copyright (c) 2014, 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.

 */

import java.io.FilePermission;

import java.io.IOException;

import java.lang.reflect.Field;

import java.lang.reflect.ReflectPermission;

import java.net.URI;

import java.nio.file.FileSystem;

import java.nio.file.FileSystems;

import java.nio.file.Files;

import java.nio.file.Path;

import java.security.CodeSource;

import java.security.Permission;

import java.security.PermissionCollection;

import java.security.Permissions;

import java.security.Policy;

import java.security.ProtectionDomain;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.Collections;

import java.util.Enumeration;

import java.util.Iterator;

import java.util.List;

import java.util.PropertyPermission;

import java.util.concurrent.atomic.AtomicBoolean;

import java.util.concurrent.atomic.AtomicLong;

import java.util.stream.Stream;

/**

 * @test

 * @bug 8065552

 * @summary test that all fields returned by getDeclaredFields() can be

 *          set accessible if the right permission is granted; this test

 *          loads all the classes in the BCL, get their declared fields,

 *          and call setAccessible(false) followed by setAccessible(true);

 * @run main/othervm FieldSetAccessibleTest UNSECURE

 * @run main/othervm FieldSetAccessibleTest SECURE

 *

 * @author danielfuchs

 */

public class FieldSetAccessibleTest {

    static final List<String> skipped = new ArrayList<>();

    static final List<String> cantread = new ArrayList<>();

    static final List<String> failed = new ArrayList<>();

    static final AtomicLong classCount = new AtomicLong();

    static final AtomicLong fieldCount = new AtomicLong();

    static long startIndex = 0;

    static long maxSize = Long.MAX_VALUE;

    static long maxIndex = Long.MAX_VALUE;

    static final ClassLoader systemClassLoader = ClassLoader.getSystemClassLoader();

    // Test that all fields for any given class can be made accessibles

    static void testSetFieldsAccessible(Class<?> c) {

        for (Field f : c.getDeclaredFields()) {

            fieldCount.incrementAndGet();

            f.setAccessible(false);

            f.setAccessible(true);

        }

    }

    // Performs a series of test on the given class.

    // At this time, we only call testSetFieldsAccessible(c)

    public static boolean test(Class<?> c) {

        //System.out.println(c.getName());

        classCount.incrementAndGet();

        // Call getDeclaredFields() and try to set their accessible flag.

        testSetFieldsAccessible(c);

        // add more tests here...

        return c == Class.class;

    }

    // Prints a summary at the end of the test.

    static void printSummary(long secs, long millis, long nanos) {

        System.out.println("Tested " + fieldCount.get() + " fields of "

                + classCount.get() + " classes in "

                + secs + "s " + millis + "ms " + nanos + "ns");

    }

    /**

     * @param args the command line arguments:

     *

     *     SECURE|UNSECURE [startIndex (default=0)] [maxSize (default=Long.MAX_VALUE)]

     *

     * @throws java.lang.Exception if the test fails

     */

    public static void main(String[] args) throws Exception {

        if (args == null || args.length == 0) {

            args = new String[] {"SECURE", "0"};

        } else if (args.length > 3) {

            throw new RuntimeException("Expected at most one argument. Found "

                    + Arrays.asList(args));

        }

        try {

            if (args.length > 1) {

                startIndex = Long.parseLong(args[1]);

                if (startIndex < 0) {

                    throw new IllegalArgumentException("startIndex args[1]: "

                            + startIndex);

                }

            }

            if (args.length > 2) {

                maxSize = Long.parseLong(args[2]);

                if (maxSize <= 0) {

                    maxSize = Long.MAX_VALUE;

                }

                maxIndex = (Long.MAX_VALUE - startIndex) < maxSize

                        ? Long.MAX_VALUE : startIndex + maxSize;

            }

            TestCase.valueOf(args[0]).run();

        } catch (OutOfMemoryError oome) {

            System.err.println(classCount.get());

            throw oome;

        }

    }

    public static void run(TestCase test) {

        System.out.println("Testing " + test);

        test(listAllClassNames());

        System.out.println("Passed " + test);

    }

    static Iterable<String> listAllClassNames() {

        return new ClassNameJrtStreamBuilder();

    }

    static void test(Iterable<String> iterable) {

        final long start = System.nanoTime();

        boolean classFound = false;

        int index = 0;

        for (String s: iterable) {

            if (index == maxIndex) break;

            try {

                if (index < startIndex) continue;

                if (test(s)) {

                    classFound = true;

                }

            } finally {

                index++;

            }

        }

        long elapsed = System.nanoTime() - start;

        long secs = elapsed / 1000_000_000;

        long millis = (elapsed % 1000_000_000) / 1000_000;

        long nanos  = elapsed % 1000_000;

        System.out.println("Unreadable path elements: " + cantread);

        System.out.println("Skipped path elements: " + skipped);

        System.out.println("Failed path elements: " + failed);

        printSummary(secs, millis, nanos);

        if (!failed.isEmpty()) {

            throw new RuntimeException("Test failed for the following classes: " + failed);

        }

        if (!classFound && startIndex == 0 && index < maxIndex) {

            // this is just to verify that we have indeed parsed rt.jar

            // (or the java.base module)

            throw  new RuntimeException("Test failed: Class.class not found...");

        }

        if (classCount.get() == 0 && startIndex == 0) {

            throw  new RuntimeException("Test failed: no class found?");

        }

    }

    static boolean test(String s) {

        try {

            if (s.startsWith("WrapperGenerator")) {

                System.out.println("Skipping "+ s);

                return false;

            }

            final Class<?> c = Class.forName(

                    s.replace('/', '.').substring(0, s.length() - 6),

                    false,

                    systemClassLoader);

            return test(c);

        } catch (Exception t) {

            t.printStackTrace(System.err);

            failed.add(s);

        } catch (NoClassDefFoundError e) {

            e.printStackTrace(System.err);

            failed.add(s);

        }

        return false;

    }

    static class ClassNameJrtStreamBuilder implements Iterable<String>{

        final FileSystem jrt;

        final List<Path> roots = new ArrayList<>();

        ClassNameJrtStreamBuilder() {

             jrt = FileSystems.getFileSystem(URI.create("jrt:/"));

             for (Path root : jrt.getRootDirectories()) {

                 roots.add(root);

             }

        }

        Stream<String> build() {

            return roots.stream().flatMap(this::toStream)

                    .filter(x -> x.getNameCount() > 2)

                    .map( x-> x.subpath(2, x.getNameCount()))

                    .map( x -> x.toString())

                    .filter(s -> s.endsWith(".class"));

        }

        @Override

        public Iterator<String> iterator() {

            return build().iterator();

        }

        private Stream<Path> toStream(Path root) {

            try {

                return Files.walk(root);

            } catch(IOException x) {

                x.printStackTrace(System.err);

                skipped.add(root.toString());

            }

            return Collections.<Path>emptyList().stream();

        }

    }

    // Test with or without a security manager

    public static enum TestCase {

        UNSECURE, SECURE;

        public void run() throws Exception {

            System.out.println("Running test case: " + name());

            Configure.setUp(this);

            FieldSetAccessibleTest.run(this);

        }

    }

    // A helper class to configure the security manager for the test,

    // and bypass it when needed.

    static class Configure {

        static Policy policy = null;

        static final ThreadLocal<AtomicBoolean> allowAll = new ThreadLocal<AtomicBoolean>() {

            @Override

            protected AtomicBoolean initialValue() {

                return  new AtomicBoolean(false);

            }

        };

        static void setUp(TestCase test) {

            switch (test) {

                case SECURE:

                    if (policy == null && System.getSecurityManager() != null) {

                        throw new IllegalStateException("SecurityManager already set");

                    } else if (policy == null) {

                        policy = new SimplePolicy(TestCase.SECURE, allowAll);

                        Policy.setPolicy(policy);

                        System.setSecurityManager(new SecurityManager());

                    }

                    if (System.getSecurityManager() == null) {

                        throw new IllegalStateException("No SecurityManager.");

                    }

                    if (policy == null) {

                        throw new IllegalStateException("policy not configured");

                    }

                    break;

                case UNSECURE:

                    if (System.getSecurityManager() != null) {

                        throw new IllegalStateException("SecurityManager already set");

                    }

                    break;

                default:

                    throw new InternalError("No such testcase: " + test);

            }

        }

        static void doPrivileged(Runnable run) {

            allowAll.get().set(true);

            try {

                run.run();

            } finally {

                allowAll.get().set(false);

            }

        }

    }

    // A Helper class to build a set of permissions.

        final Permissions perms;

        public PermissionsBuilder() {

            this(new Permissions());

        }

        public PermissionsBuilder(Permissions perms) {

            this.perms = perms;

        }

        public PermissionsBuilder add(Permission p) {

            perms.add(p);

            return this;

        }

        public PermissionsBuilder addAll(PermissionCollection col) {

            if (col != null) {

                for (Enumeration<Permission> e = col.elements(); e.hasMoreElements(); ) {

                    perms.add(e.nextElement());

                }

            }

            return this;

        }

        public Permissions toPermissions() {

            final PermissionsBuilder builder = new PermissionsBuilder();

            builder.addAll(perms);

            return builder.perms;

        }

    }

    // Policy for the test...

    public static class SimplePolicy extends Policy {

        final Permissions permissions;

        final Permissions allPermissions;

        final ThreadLocal<AtomicBoolean> allowAll;

        public SimplePolicy(TestCase test, ThreadLocal<AtomicBoolean> allowAll) {

            this.allowAll = allowAll;

            // Permission needed by the tested code exercised in the test

            permissions = new Permissions();

            permissions.add(new RuntimePermission("fileSystemProvider"));

            permissions.add(new RuntimePermission("createClassLoader"));

            permissions.add(new RuntimePermission("closeClassLoader"));

            permissions.add(new RuntimePermission("getClassLoader"));

            permissions.add(new RuntimePermission("accessDeclaredMembers"));

            permissions.add(new ReflectPermission("suppressAccessChecks"));

            permissions.add(new PropertyPermission("*", "read"));

            permissions.add(new FilePermission("<<ALL FILES>>", "read"));

            // these are used for configuring the test itself...

            allPermissions = new Permissions();

            allPermissions.add(new java.security.AllPermission());

        }

        @Override

        public boolean implies(ProtectionDomain domain, Permission permission) {

            if (allowAll.get().get()) return allPermissions.implies(permission);

            if (permissions.implies(permission)) return true;

            if (permission instanceof java.lang.RuntimePermission) {

                if (permission.getName().startsWith("accessClassInPackage.")) {

                    // add these along to the set of permission we have, when we

                    // discover that we need them.

                    permissions.add(permission);

                    return true;

                }

            }

            return false;

        }

        @Override

        public PermissionCollection getPermissions(CodeSource codesource) {

            return new PermissionsBuilder().addAll(allowAll.get().get()

                    ? allPermissions : permissions).toPermissions();

        }

        @Override

        public PermissionCollection getPermissions(ProtectionDomain domain) {

            return new PermissionsBuilder().addAll(allowAll.get().get()

                    ? allPermissions : permissions).toPermissions();

        }

    }

}