1 /* 2 * Copyright 2012, Google Inc. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are 7 * met: 8 * 9 * * Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * * Redistributions in binary form must reproduce the above 12 * copyright notice, this list of conditions and the following disclaimer 13 * in the documentation and/or other materials provided with the 14 * distribution. 15 * * Neither the name of Google Inc. nor the names of its 16 * contributors may be used to endorse or promote products derived from 17 * this software without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 20 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 21 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 22 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 23 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 24 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 25 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 29 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 package org.jf.dexlib2.util; 33 34 import com.google.common.collect.ImmutableList; 35 import com.google.common.collect.ImmutableMap; 36 import com.google.common.collect.Maps; 37 import org.jf.dexlib2.AccessFlags; 38 import org.jf.dexlib2.iface.ClassDef; 39 import org.jf.dexlib2.iface.Method; 40 import org.jf.dexlib2.iface.MethodImplementation; 41 import org.jf.dexlib2.iface.instruction.Instruction; 42 import org.jf.dexlib2.iface.instruction.ReferenceInstruction; 43 import org.jf.dexlib2.iface.reference.MethodReference; 44 import org.jf.dexlib2.iface.reference.Reference; 45 46 import javax.annotation.Nonnull; 47 import javax.annotation.Nullable; 48 import java.util.List; 49 import java.util.Map; 50 51 public class SyntheticAccessorResolver { 52 public static final int METHOD = 0; 53 public static final int GETTER = 1; 54 public static final int SETTER = 2; 55 public static final int POSTFIX_INCREMENT = 3; 56 public static final int PREFIX_INCREMENT = 4; 57 public static final int POSTFIX_DECREMENT = 5; 58 public static final int PREFIX_DECREMENT = 6; 59 public static final int ADD_ASSIGNMENT = 7; 60 public static final int SUB_ASSIGNMENT = 8; 61 public static final int MUL_ASSIGNMENT = 9; 62 public static final int DIV_ASSIGNMENT = 10; 63 public static final int REM_ASSIGNMENT = 11; 64 public static final int AND_ASSIGNMENT = 12; 65 public static final int OR_ASSIGNMENT = 13; 66 public static final int XOR_ASSIGNMENT = 14; 67 public static final int SHL_ASSIGNMENT = 15; 68 public static final int SHR_ASSIGNMENT = 16; 69 public static final int USHR_ASSIGNMENT = 17; 70 71 private final Map<String, ClassDef> classDefMap; 72 private final Map<String, AccessedMember> resolvedAccessors = Maps.newConcurrentMap(); 73 74 public SyntheticAccessorResolver(Iterable<? extends ClassDef> classDefs) { 75 ImmutableMap.Builder<String, ClassDef> builder = ImmutableMap.builder(); 76 77 for (ClassDef classDef: classDefs) { 78 builder.put(classDef.getType(), classDef); 79 } 80 81 this.classDefMap = builder.build(); 82 } 83 84 public static boolean looksLikeSyntheticAccessor(String methodName) { 85 return methodName.startsWith("access$"); 86 } 87 88 @Nullable 89 public AccessedMember getAccessedMember(@Nonnull MethodReference methodReference) { 90 String methodDescriptor = ReferenceUtil.getMethodDescriptor(methodReference); 91 92 AccessedMember accessedMember = resolvedAccessors.get(methodDescriptor); 93 if (accessedMember != null) { 94 return accessedMember; 95 } 96 97 String type = methodReference.getDefiningClass(); 98 ClassDef classDef = classDefMap.get(type); 99 if (classDef == null) { 100 return null; 101 } 102 103 Method matchedMethod = null; 104 MethodImplementation matchedMethodImpl = null; 105 for (Method method: classDef.getMethods()) { 106 MethodImplementation methodImpl = method.getImplementation(); 107 if (methodImpl != null) { 108 if (methodReferenceEquals(method, methodReference)) { 109 matchedMethod = method; 110 matchedMethodImpl = methodImpl; 111 break; 112 } 113 } 114 } 115 116 if (matchedMethod == null) { 117 return null; 118 } 119 120 //A synthetic accessor will be marked synthetic 121 if (!AccessFlags.SYNTHETIC.isSet(matchedMethod.getAccessFlags())) { 122 return null; 123 } 124 125 List<Instruction> instructions = ImmutableList.copyOf(matchedMethodImpl.getInstructions()); 126 127 int accessType = SyntheticAccessorFSM.test(instructions); 128 129 if (accessType >= 0) { 130 AccessedMember member = 131 new AccessedMember(accessType, ((ReferenceInstruction)instructions.get(0)).getReference()); 132 resolvedAccessors.put(methodDescriptor, member); 133 return member; 134 } 135 return null; 136 } 137 138 public static class AccessedMember { 139 public final int accessedMemberType; 140 @Nonnull public final Reference accessedMember; 141 142 public AccessedMember(int accessedMemberType, @Nonnull Reference accessedMember) { 143 this.accessedMemberType = accessedMemberType; 144 this.accessedMember = accessedMember; 145 } 146 } 147 148 private static boolean methodReferenceEquals(@Nonnull MethodReference ref1, @Nonnull MethodReference ref2) { 149 // we already know the containing class matches 150 return ref1.getName().equals(ref2.getName()) && 151 ref1.getReturnType().equals(ref2.getReturnType()) && 152 ref1.getParameterTypes().equals(ref2.getParameterTypes()); 153 } 154 } 155