/*

 * 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.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * 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.

 */

/*

 * This file is available under and governed by the GNU General Public

 * License version 2 only, as published by the Free Software Foundation.

 * However, the following notice accompanied the original version of this

 * file:

 *

 * ASM: a very small and fast Java bytecode manipulation framework

 * Copyright (c) 2000-2011 INRIA, France Telecom

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 * 3. Neither the name of the copyright holders nor the names of its

 *    contributors may be used to endorse or promote products derived from

 *    this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE

 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN

 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF

 * THE POSSIBILITY OF SUCH DAMAGE.

 */

package jdk.internal.org.objectweb.asm.util;

import java.io.PrintWriter;

import java.io.StringWriter;

import java.lang.reflect.Field;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.HashSet;

import java.util.List;

import java.util.Map;

import java.util.Set;

import jdk.internal.org.objectweb.asm.AnnotationVisitor;

import jdk.internal.org.objectweb.asm.Attribute;

import jdk.internal.org.objectweb.asm.Handle;

import jdk.internal.org.objectweb.asm.Label;

import jdk.internal.org.objectweb.asm.MethodVisitor;

import jdk.internal.org.objectweb.asm.Opcodes;

import jdk.internal.org.objectweb.asm.Type;

import jdk.internal.org.objectweb.asm.TypePath;

import jdk.internal.org.objectweb.asm.TypeReference;

import jdk.internal.org.objectweb.asm.tree.MethodNode;

import jdk.internal.org.objectweb.asm.tree.analysis.Analyzer;

import jdk.internal.org.objectweb.asm.tree.analysis.BasicValue;

import jdk.internal.org.objectweb.asm.tree.analysis.BasicVerifier;

/**

 * A {@link MethodVisitor} that checks that its methods are properly used. More

 * precisely this method adapter checks each instruction individually, i.e.,

 * each visit method checks some preconditions based <i>only</i> on its

 * arguments - such as the fact that the given opcode is correct for a given

 * visit method. This adapter can also perform some basic data flow checks (more

 * precisely those that can be performed without the full class hierarchy - see

 * {@link jdk.internal.org.objectweb.asm.tree.analysis.BasicVerifier}). For instance in a

 * method whose signature is <tt>void m ()</tt>, the invalid instruction

 * IRETURN, or the invalid sequence IADD L2I will be detected if the data flow

 * checks are enabled. These checks are enabled by using the

 * {@link #CheckMethodAdapter(int,String,String,MethodVisitor,Map)} constructor.

 * They are not performed if any other constructor is used.

 *

 * @author Eric Bruneton

 */

public class CheckMethodAdapter extends MethodVisitor {

    /**

     * The class version number.

     */

    public int version;

    /**

     * The access flags of the method.

     */

    private int access;

    /**

     * <tt>true</tt> if the visitCode method has been called.

     */

    private boolean startCode;

    /**

     * <tt>true</tt> if the visitMaxs method has been called.

     */

    private boolean endCode;

    /**

     * <tt>true</tt> if the visitEnd method has been called.

     */

    private boolean endMethod;

    /**

     * Number of visited instructions.

     */

    private int insnCount;

    /**

     * The already visited labels. This map associate Integer values to pseudo

     * code offsets.

     */

    private final Map<Label, Integer> labels;

    /**

     * The labels used in this method. Every used label must be visited with

     * visitLabel before the end of the method (i.e. should be in #labels).

     */

    private Set<Label> usedLabels;

    /**

     * Number of visited frames in expanded form.

     */

    private int expandedFrames;

    /**

     * Number of visited frames in compressed form.

     */

    private int compressedFrames;

    /**

     * The exception handler ranges. Each pair of list element contains the

     * start and end labels of an exception handler block.

     */

    private List<Label> handlers;

    /**

     * Code of the visit method to be used for each opcode.

     */

    private static final int[] TYPE;

    /**

     * The Label.status field.

     */

    private static Field labelStatusField;

    static {

        String s = "BBBBBBBBBBBBBBBBCCIAADDDDDAAAAAAAAAAAAAAAAAAAABBBBBBBBDD"

                + "DDDAAAAAAAAAAAAAAAAAAAABBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB"

                + "BBBBBBBBBBBBBBBBBBBJBBBBBBBBBBBBBBBBBBBBHHHHHHHHHHHHHHHHD"

                + "KLBBBBBBFFFFGGGGAECEBBEEBBAMHHAA";

        TYPE = new int[s.length()];

        for (int i = 0; i < TYPE.length; ++i) {

            TYPE[i] = s.charAt(i) - 'A' - 1;

        }

    }

    // code to generate the above string

    // public static void main (String[] args) {

    // int[] TYPE = new int[] {

    // 0, //NOP

    // 0, //ACONST_NULL

    // 0, //ICONST_M1

    // 0, //ICONST_0

    // 0, //ICONST_1

    // 0, //ICONST_2

    // 0, //ICONST_3

    // 0, //ICONST_4

    // 0, //ICONST_5

    // 0, //LCONST_0

    // 0, //LCONST_1

    // 0, //FCONST_0

    // 0, //FCONST_1

    // 0, //FCONST_2

    // 0, //DCONST_0

    // 0, //DCONST_1

    // 1, //BIPUSH

    // 1, //SIPUSH

    // 7, //LDC

    // -1, //LDC_W

    // -1, //LDC2_W

    // 2, //ILOAD

    // 2, //LLOAD

    // 2, //FLOAD

    // 2, //DLOAD

    // 2, //ALOAD

    // -1, //ILOAD_0

    // -1, //ILOAD_1

    // -1, //ILOAD_2

    // -1, //ILOAD_3

    // -1, //LLOAD_0

    // -1, //LLOAD_1

    // -1, //LLOAD_2

    // -1, //LLOAD_3

    // -1, //FLOAD_0

    // -1, //FLOAD_1

    // -1, //FLOAD_2

    // -1, //FLOAD_3

    // -1, //DLOAD_0

    // -1, //DLOAD_1

    // -1, //DLOAD_2

    // -1, //DLOAD_3

    // -1, //ALOAD_0

    // -1, //ALOAD_1

    // -1, //ALOAD_2

    // -1, //ALOAD_3

    // 0, //IALOAD

    // 0, //LALOAD

    // 0, //FALOAD

    // 0, //DALOAD

    // 0, //AALOAD

    // 0, //BALOAD

    // 0, //CALOAD

    // 0, //SALOAD

    // 2, //ISTORE

    // 2, //LSTORE

    // 2, //FSTORE

    // 2, //DSTORE

    // 2, //ASTORE

    // -1, //ISTORE_0

    // -1, //ISTORE_1

    // -1, //ISTORE_2

    // -1, //ISTORE_3

    // -1, //LSTORE_0

    // -1, //LSTORE_1

    // -1, //LSTORE_2

    // -1, //LSTORE_3

    // -1, //FSTORE_0

    // -1, //FSTORE_1

    // -1, //FSTORE_2

    // -1, //FSTORE_3

    // -1, //DSTORE_0

    // -1, //DSTORE_1

    // -1, //DSTORE_2

    // -1, //DSTORE_3

    // -1, //ASTORE_0

    // -1, //ASTORE_1

    // -1, //ASTORE_2

    // -1, //ASTORE_3

    // 0, //IASTORE

    // 0, //LASTORE

    // 0, //FASTORE

    // 0, //DASTORE

    // 0, //AASTORE

    // 0, //BASTORE

    // 0, //CASTORE

    // 0, //SASTORE

    // 0, //POP

    // 0, //POP2

    // 0, //DUP

    // 0, //DUP_X1

    // 0, //DUP_X2

    // 0, //DUP2

    // 0, //DUP2_X1

    // 0, //DUP2_X2

    // 0, //SWAP

    // 0, //IADD

    // 0, //LADD

    // 0, //FADD

    // 0, //DADD

    // 0, //ISUB

    // 0, //LSUB

    // 0, //FSUB

    // 0, //DSUB

    // 0, //IMUL

    // 0, //LMUL

    // 0, //FMUL

    // 0, //DMUL

    // 0, //IDIV

    // 0, //LDIV

    // 0, //FDIV

    // 0, //DDIV

    // 0, //IREM

    // 0, //LREM

    // 0, //FREM

    // 0, //DREM

    // 0, //INEG

    // 0, //LNEG

    // 0, //FNEG

    // 0, //DNEG

    // 0, //ISHL

    // 0, //LSHL

    // 0, //ISHR

    // 0, //LSHR

    // 0, //IUSHR

    // 0, //LUSHR

    // 0, //IAND

    // 0, //LAND

    // 0, //IOR

    // 0, //LOR

    // 0, //IXOR

    // 0, //LXOR

    // 8, //IINC

    // 0, //I2L

    // 0, //I2F

    // 0, //I2D

    // 0, //L2I

    // 0, //L2F

    // 0, //L2D

    // 0, //F2I

    // 0, //F2L

    // 0, //F2D

    // 0, //D2I

    // 0, //D2L

    // 0, //D2F

    // 0, //I2B

    // 0, //I2C

    // 0, //I2S

    // 0, //LCMP

    // 0, //FCMPL

    // 0, //FCMPG

    // 0, //DCMPL

    // 0, //DCMPG

    // 6, //IFEQ

    // 6, //IFNE

    // 6, //IFLT

    // 6, //IFGE

    // 6, //IFGT

    // 6, //IFLE

    // 6, //IF_ICMPEQ

    // 6, //IF_ICMPNE

    // 6, //IF_ICMPLT

    // 6, //IF_ICMPGE

    // 6, //IF_ICMPGT

    // 6, //IF_ICMPLE

    // 6, //IF_ACMPEQ

    // 6, //IF_ACMPNE

    // 6, //GOTO

    // 6, //JSR

    // 2, //RET

    // 9, //TABLESWITCH

    // 10, //LOOKUPSWITCH

    // 0, //IRETURN

    // 0, //LRETURN

    // 0, //FRETURN

    // 0, //DRETURN

    // 0, //ARETURN

    // 0, //RETURN

    // 4, //GETSTATIC

    // 4, //PUTSTATIC

    // 4, //GETFIELD

    // 4, //PUTFIELD

    // 5, //INVOKEVIRTUAL

    // 5, //INVOKESPECIAL

    // 5, //INVOKESTATIC

    // 5, //INVOKEINTERFACE

    // -1, //INVOKEDYNAMIC

    // 3, //NEW

    // 1, //NEWARRAY

    // 3, //ANEWARRAY

    // 0, //ARRAYLENGTH

    // 0, //ATHROW

    // 3, //CHECKCAST

    // 3, //INSTANCEOF

    // 0, //MONITORENTER

    // 0, //MONITOREXIT

    // -1, //WIDE

    // 11, //MULTIANEWARRAY

    // 6, //IFNULL

    // 6, //IFNONNULL

    // -1, //GOTO_W

    // -1 //JSR_W

    // };

    // for (int i = 0; i < TYPE.length; ++i) {

    // System.out.print((char)(TYPE[i] + 1 + 'A'));

    // }

    // System.out.println();

    // }

    /**

     * Constructs a new {@link CheckMethodAdapter} object. This method adapter

     * will not perform any data flow check (see

     * {@link #CheckMethodAdapter(int,String,String,MethodVisitor,Map)}).

     * <i>Subclasses must not use this constructor</i>. Instead, they must use

     * the {@link #CheckMethodAdapter(int, MethodVisitor, Map)} version.

     *

     * @param mv

     *            the method visitor to which this adapter must delegate calls.

     */

    public CheckMethodAdapter(final MethodVisitor mv) {

        this(mv, new HashMap<Label, Integer>());

    }

    /**

     * Constructs a new {@link CheckMethodAdapter} object. This method adapter

     * will not perform any data flow check (see

     * {@link #CheckMethodAdapter(int,String,String,MethodVisitor,Map)}).

     * <i>Subclasses must not use this constructor</i>. Instead, they must use

     * the {@link #CheckMethodAdapter(int, MethodVisitor, Map)} version.

     *

     * @param mv

     *            the method visitor to which this adapter must delegate calls.

     * @param labels

     *            a map of already visited labels (in other methods).

     */

    public CheckMethodAdapter(final MethodVisitor mv,

            final Map<Label, Integer> labels) {

        this(Opcodes.ASM5, mv, labels);

    }

    /**

     * Constructs a new {@link CheckMethodAdapter} object. This method adapter

     * will not perform any data flow check (see

     * {@link #CheckMethodAdapter(int,String,String,MethodVisitor,Map)}).

     *

     * @param mv

     *            the method visitor to which this adapter must delegate calls.

     * @param labels

     *            a map of already visited labels (in other methods).

     */

    protected CheckMethodAdapter(final int api, final MethodVisitor mv,

            final Map<Label, Integer> labels) {

        super(api, mv);

        this.labels = labels;

        this.usedLabels = new HashSet<Label>();

        this.handlers = new ArrayList<Label>();

    }

    /**

     * Constructs a new {@link CheckMethodAdapter} object. This method adapter

     * will perform basic data flow checks. For instance in a method whose

     * signature is <tt>void m ()</tt>, the invalid instruction IRETURN, or the

     * invalid sequence IADD L2I will be detected.

     *

     * @param access

     *            the method's access flags.

     * @param name

     *            the method's name.

     * @param desc

     *            the method's descriptor (see {@link Type Type}).

     * @param cmv

     *            the method visitor to which this adapter must delegate calls.

     * @param labels

     *            a map of already visited labels (in other methods).

     */

    public CheckMethodAdapter(final int access, final String name,

            final String desc, final MethodVisitor cmv,

            final Map<Label, Integer> labels) {

            @Override

            public void visitEnd() {

                Analyzer<BasicValue> a = new Analyzer<BasicValue>(

                        new BasicVerifier());

                try {

                    a.analyze("dummy", this);

                } catch (Exception e) {

                    if (e instanceof IndexOutOfBoundsException

                            && maxLocals == 0 && maxStack == 0) {

                        throw new RuntimeException(

                                "Data flow checking option requires valid, non zero maxLocals and maxStack values.");

                    }

                    e.printStackTrace();

                    StringWriter sw = new StringWriter();

                    PrintWriter pw = new PrintWriter(sw, true);

                    CheckClassAdapter.printAnalyzerResult(this, a, pw);

                    pw.close();

                    throw new RuntimeException(e.getMessage() + ' '

                            + sw.toString());

                }

                accept(cmv);

            }

        }, labels);

        this.access = access;

    }

    @Override

    public void visitParameter(String name, int access) {

        if (name != null) {

            checkUnqualifiedName(version, name, "name");

        }

        CheckClassAdapter.checkAccess(access, Opcodes.ACC_FINAL

                + Opcodes.ACC_MANDATED + Opcodes.ACC_SYNTHETIC);

    }

    @Override

    public AnnotationVisitor visitAnnotation(final String desc,

            final boolean visible) {

        checkEndMethod();

        checkDesc(desc, false);

        return new CheckAnnotationAdapter(super.visitAnnotation(desc, visible));

    }

    @Override

    public AnnotationVisitor visitTypeAnnotation(final int typeRef,

            final TypePath typePath, final String desc, final boolean visible) {

        checkEndMethod();