1/* 2 * [The "BSD licence"] 3 * Copyright (c) 2010 Ben Gruver (JesusFreke) 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. The name of the author may not be used to endorse or promote products 15 * derived from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29package org.jf.dexlib.Code.Format; 30 31import org.jf.dexlib.Code.Instruction; 32import org.jf.dexlib.Code.MultiOffsetInstruction; 33import org.jf.dexlib.Code.Opcode; 34import org.jf.dexlib.DexFile; 35import org.jf.dexlib.Util.AnnotatedOutput; 36import org.jf.dexlib.Util.NumberUtils; 37 38import java.util.Iterator; 39 40public class PackedSwitchDataPseudoInstruction extends Instruction implements MultiOffsetInstruction { 41 public static final Instruction.InstructionFactory Factory = new Factory(); 42 private int firstKey; 43 private int[] targets; 44 45 @Override 46 public int getSize(int codeAddress) { 47 return getTargetCount() * 2 + 4 + (codeAddress % 2); 48 } 49 50 public PackedSwitchDataPseudoInstruction(int firstKey, int[] targets) { 51 super(Opcode.NOP); 52 53 if (targets.length > 0xFFFF) { 54 throw new RuntimeException("The packed-switch data contains too many elements. " + 55 "The maximum number of switch elements is 65535"); 56 } 57 58 this.firstKey = firstKey; 59 this.targets = targets; 60 } 61 62 public PackedSwitchDataPseudoInstruction(byte[] buffer, int bufferIndex) { 63 super(Opcode.NOP); 64 65 byte opcodeByte = buffer[bufferIndex]; 66 if (opcodeByte != 0x00) { 67 throw new RuntimeException("Invalid opcode byte for a PackedSwitchData pseudo-instruction"); 68 } 69 byte subopcodeByte = buffer[bufferIndex+1]; 70 if (subopcodeByte != 0x01) { 71 throw new RuntimeException("Invalid sub-opcode byte for a PackedSwitchData pseudo-instruction"); 72 } 73 74 int targetCount = NumberUtils.decodeUnsignedShort(buffer, bufferIndex + 2); 75 this.firstKey = NumberUtils.decodeInt(buffer, bufferIndex + 4); 76 this.targets = new int[targetCount]; 77 78 for (int i = 0; i<targetCount; i++) { 79 targets[i] = NumberUtils.decodeInt(buffer, bufferIndex + 8 + 4*i); 80 } 81 } 82 83 protected void writeInstruction(AnnotatedOutput out, int currentCodeAddress) { 84 out.alignTo(4); 85 86 out.writeByte(0x00); 87 out.writeByte(0x01); 88 out.writeShort(targets.length); 89 out.writeInt(firstKey); 90 91 for (int target : targets) { 92 out.writeInt(target); 93 } 94 } 95 96 protected void annotateInstruction(AnnotatedOutput out, int currentCodeAddress) { 97 out.annotate(getSize(currentCodeAddress)*2, "[0x" + Integer.toHexString(currentCodeAddress) + "] " + 98 "packed-switch-data instruction"); 99 } 100 101 public void updateTarget(int targetIndex, int targetAddressOffset) { 102 targets[targetIndex] = targetAddressOffset; 103 } 104 105 public Format getFormat() { 106 return Format.PackedSwitchData; 107 } 108 109 public int getTargetCount() { 110 return targets.length; 111 } 112 113 public int getFirstKey() { 114 return firstKey; 115 } 116 117 public int[] getTargets() { 118 return targets; 119 } 120 121 public static class PackedSwitchTarget { 122 public int value; 123 public int targetAddressOffset; 124 } 125 126 public Iterator<PackedSwitchTarget> iterateKeysAndTargets() { 127 return new Iterator<PackedSwitchTarget>() { 128 final int targetCount = getTargetCount(); 129 int i = 0; 130 int value = getFirstKey(); 131 132 PackedSwitchTarget packedSwitchTarget = new PackedSwitchTarget(); 133 134 public boolean hasNext() { 135 return i<targetCount; 136 } 137 138 public PackedSwitchTarget next() { 139 packedSwitchTarget.value = value++; 140 packedSwitchTarget.targetAddressOffset = targets[i]; 141 i++; 142 return packedSwitchTarget; 143 } 144 145 public void remove() { 146 } 147 }; 148 } 149 150 private static class Factory implements Instruction.InstructionFactory { 151 public Instruction makeInstruction(DexFile dexFile, Opcode opcode, byte[] buffer, int bufferIndex) { 152 if (opcode != Opcode.NOP) { 153 throw new RuntimeException("The opcode for a PackedSwitchDataPseudoInstruction must be NOP"); 154 } 155 return new PackedSwitchDataPseudoInstruction(buffer, bufferIndex); 156 } 157 } 158} 159