| package org.apache.maven.shared.dependency.analyzer.asm; |
| |
| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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.nio.Buffer; |
| import java.nio.ByteBuffer; |
| import java.nio.ByteOrder; |
| import java.util.Collections; |
| import java.util.HashMap; |
| import java.util.HashSet; |
| import java.util.Map; |
| import java.util.Set; |
| |
| /** |
| * A small parser to read the constant pool directly, in case it contains references |
| * ASM does not support. |
| * |
| * Adapted from http://stackoverflow.com/a/32278587/23691 |
| * |
| * Constant pool types: |
| * |
| * @see <a href="https://docs.oracle.com/javase/specs/jvms/se9/html/jvms-4.html#jvms-4.4">JVM 9 Sepc</a> |
| * @see <a href="https://docs.oracle.com/javase/specs/jvms/se10/html/jvms-4.html#jvms-4.4">JVM 10 Sepc</a> |
| */ |
| public class ConstantPoolParser |
| { |
| /** Constant <code>HEAD=0xcafebabe</code> */ |
| public static final int HEAD = 0xcafebabe; |
| |
| // Constant pool types |
| |
| /** Constant <code>CONSTANT_UTF8=1</code> */ |
| public static final byte CONSTANT_UTF8 = 1; |
| |
| /** Constant <code>CONSTANT_INTEGER=3</code> */ |
| public static final byte CONSTANT_INTEGER = 3; |
| |
| /** Constant <code>CONSTANT_FLOAT=4</code> */ |
| public static final byte CONSTANT_FLOAT = 4; |
| |
| /** Constant <code>CONSTANT_LONG=5</code> */ |
| public static final byte CONSTANT_LONG = 5; |
| |
| /** Constant <code>CONSTANT_DOUBLE=6</code> */ |
| public static final byte CONSTANT_DOUBLE = 6; |
| |
| /** Constant <code>CONSTANT_CLASS=7</code> */ |
| public static final byte CONSTANT_CLASS = 7; |
| |
| /** Constant <code>CONSTANT_STRING=8</code> */ |
| public static final byte CONSTANT_STRING = 8; |
| |
| /** Constant <code>CONSTANT_FIELDREF=9</code> */ |
| public static final byte CONSTANT_FIELDREF = 9; |
| |
| /** Constant <code>CONSTANT_METHODREF=10</code> */ |
| public static final byte CONSTANT_METHODREF = 10; |
| |
| /** Constant <code>CONSTANT_INTERFACEMETHODREF=11</code> */ |
| public static final byte CONSTANT_INTERFACEMETHODREF = 11; |
| |
| /** Constant <code>CONSTANT_NAME_AND_TYPE=12</code> */ |
| public static final byte CONSTANT_NAME_AND_TYPE = 12; |
| |
| /** Constant <code>CONSTANT_METHODHANDLE=15</code> */ |
| public static final byte CONSTANT_METHODHANDLE = 15; |
| |
| /** Constant <code>CONSTANT_METHOD_TYPE=16</code> */ |
| public static final byte CONSTANT_METHOD_TYPE = 16; |
| |
| /** Constant <code>CONSTANT_INVOKE_DYNAMIC=18</code> */ |
| public static final byte CONSTANT_INVOKE_DYNAMIC = 18; |
| |
| /** Constant <code>CONSTANT_MODULE=19</code> */ |
| public static final byte CONSTANT_MODULE = 19; |
| |
| /** Constant <code>CONSTANT_PACKAGE=20</code> */ |
| public static final byte CONSTANT_PACKAGE = 20; |
| |
| private static final int OXF0 = 0xf0; |
| |
| private static final int OXE0 = 0xe0; |
| |
| private static final int OX3F = 0x3F; |
| |
| static Set<String> getConstantPoolClassReferences( byte[] b ) |
| { |
| return parseConstantPoolClassReferences( ByteBuffer.wrap( b ) ); |
| } |
| |
| static Set<String> parseConstantPoolClassReferences( ByteBuffer buf ) |
| { |
| if ( buf.order( ByteOrder.BIG_ENDIAN ) |
| .getInt() != HEAD ) |
| { |
| return Collections.emptySet(); |
| } |
| buf.getChar() ; buf.getChar(); // minor + ver |
| Set<Integer> classes = new HashSet<>(); |
| Map<Integer, String> stringConstants = new HashMap<>(); |
| for ( int ix = 1, num = buf.getChar(); ix < num; ix++ ) |
| { |
| byte tag = buf.get(); |
| switch ( tag ) |
| { |
| default: |
| throw new RuntimeException( "Unknown constant pool type '" + tag + "'" ); |
| case CONSTANT_UTF8: |
| stringConstants.put( ix, decodeString( buf ) ); |
| continue; |
| case CONSTANT_CLASS: |
| case CONSTANT_METHOD_TYPE: |
| classes.add( (int) buf.getChar() ); |
| break; |
| case CONSTANT_FIELDREF: |
| case CONSTANT_METHODREF: |
| case CONSTANT_INTERFACEMETHODREF: |
| case CONSTANT_NAME_AND_TYPE: |
| consumeReference( buf ); |
| break; |
| case CONSTANT_INTEGER: |
| consumeInt( buf ); |
| break; |
| case CONSTANT_FLOAT: |
| consumeFloat( buf ); |
| break; |
| case CONSTANT_DOUBLE: |
| consumeDouble( buf ); |
| ix++; |
| break; |
| case CONSTANT_LONG: |
| consumeLong( buf ); |
| ix++; |
| break; |
| case CONSTANT_STRING: |
| consumeString( buf ); |
| break; |
| case CONSTANT_METHODHANDLE: |
| consumeMethodHandle( buf ); |
| break; |
| case CONSTANT_INVOKE_DYNAMIC: |
| consumeInvokeDynamic( buf ); |
| break; |
| case CONSTANT_MODULE: |
| consumeModule( buf ); |
| break; |
| case CONSTANT_PACKAGE: |
| consumePackage( buf ); |
| break; |
| } |
| } |
| Set<String> result = new HashSet<>(); |
| for ( Integer aClass : classes ) |
| { |
| String className = stringConstants.get( aClass ); |
| |
| // filter out things from unnamed package, probably a false-positive |
| if ( isImportableClass( className ) ) |
| { |
| result.add( className ); |
| } |
| } |
| return result; |
| } |
| |
| private static String decodeString( ByteBuffer buf ) |
| { |
| int size = buf.getChar(); |
| // Explicit cast for compatibility with covariant return type on JDK 9's ByteBuffer |
| @SuppressWarnings( "RedundantCast" ) |
| int oldLimit = ( (Buffer) buf ).limit(); |
| ( (Buffer) buf ).limit( buf.position() + size ); |
| StringBuilder sb = new StringBuilder( size + ( size >> 1 ) + 16 ); |
| while ( buf.hasRemaining() ) |
| { |
| byte b = buf.get(); |
| if ( b > 0 ) |
| { |
| sb.append( (char) b ); |
| } |
| else |
| { |
| int b2 = buf.get(); |
| if ( ( b & OXF0 ) != OXE0 ) |
| { |
| sb.append( (char) ( ( b & 0x1F ) << 6 | b2 & OX3F ) ); |
| } |
| else |
| { |
| int b3 = buf.get(); |
| sb.append( (char) ( ( b & 0x0F ) << 12 | ( b2 & OX3F ) << 6 | b3 & OX3F ) ); |
| } |
| } |
| } |
| ( (Buffer) buf ).limit( oldLimit ); |
| return sb.toString(); |
| } |
| |
| private static boolean isImportableClass( String className ) |
| { |
| // without a slash, class must be in unnamed package, which can't be imported |
| return className.indexOf( '/' ) != -1; |
| } |
| |
| private static void consumeReference( ByteBuffer buf ) |
| { |
| buf.getChar(); |
| buf.getChar(); |
| } |
| |
| private static void consumeInt( ByteBuffer buf ) |
| { |
| buf.getInt(); |
| } |
| |
| private static void consumeFloat( ByteBuffer buf ) |
| { |
| buf.getFloat(); |
| } |
| |
| private static void consumeDouble( ByteBuffer buf ) |
| { |
| buf.getDouble(); |
| } |
| |
| private static void consumeLong( ByteBuffer buf ) |
| { |
| buf.getLong(); |
| } |
| |
| private static void consumeString( ByteBuffer buf ) |
| { |
| buf.getChar(); |
| } |
| |
| private static void consumeMethodHandle( ByteBuffer buf ) |
| { |
| buf.get(); |
| buf.getChar(); |
| } |
| |
| private static void consumeInvokeDynamic( ByteBuffer buf ) |
| { |
| buf.getChar(); |
| buf.getChar(); |
| } |
| |
| private static void consumeModule( ByteBuffer buf ) |
| { |
| buf.getChar(); |
| } |
| |
| private static void consumePackage( ByteBuffer buf ) |
| { |
| buf.getChar(); |
| } |
| } |