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 SparseSwitchDataPseudoInstruction extends Instruction implements MultiOffsetInstruction { 41 public static final Instruction.InstructionFactory Factory = new Factory(); 42 private int[] keys; 43 private int[] targets; 44 45 @Override 46 public int getSize(int codeAddress) { 47 return getTargetCount() * 4 + 2 + (codeAddress % 2); 48 } 49 50 public SparseSwitchDataPseudoInstruction(int[] keys, int[] targets) { 51 super(Opcode.NOP); 52 53 if (keys.length != targets.length) { 54 throw new RuntimeException("The number of keys and targets don't match"); 55 } 56 57 if (targets.length == 0) { 58 throw new RuntimeException("The sparse-switch data must contain at least 1 key/target"); 59 } 60 61 if (targets.length > 0xFFFF) { 62 throw new RuntimeException("The sparse-switch data contains too many elements. " + 63 "The maximum number of switch elements is 65535"); 64 } 65 66 this.keys = keys; 67 this.targets = targets; 68 } 69 70 public SparseSwitchDataPseudoInstruction(byte[] buffer, int bufferIndex) { 71 super(Opcode.NOP); 72 73 byte opcodeByte = buffer[bufferIndex]; 74 if (opcodeByte != 0x00) { 75 throw new RuntimeException("Invalid opcode byte for a SparseSwitchData pseudo-instruction"); 76 } 77 byte subopcodeByte = buffer[bufferIndex+1]; 78 if (subopcodeByte != 0x02) { 79 throw new RuntimeException("Invalid sub-opcode byte for a SparseSwitchData pseudo-instruction"); 80 } 81 82 int targetCount = NumberUtils.decodeUnsignedShort(buffer, bufferIndex + 2); 83 keys = new int[targetCount]; 84 targets = new int[targetCount]; 85 86 for (int i=0; i<targetCount; i++) { 87 keys[i] = NumberUtils.decodeInt(buffer, bufferIndex + 4 + i*4); 88 targets[i] = NumberUtils.decodeInt(buffer, bufferIndex + 4 + targetCount*4 + i*4); 89 } 90 } 91 92 protected void writeInstruction(AnnotatedOutput out, int currentCodeAddress) { 93 out.alignTo(4); 94 95 out.writeByte(0x00); 96 out.writeByte(0x02); 97 out.writeShort(targets.length); 98 99 if (targets.length > 0) { 100 int key = keys[0]; 101 102 out.writeInt(key); 103 104 for (int i = 1; i < keys.length; i++) { 105 key = keys[i]; 106 assert key >= keys[i - 1]; 107 out.writeInt(key); 108 } 109 110 for (int target : targets) { 111 out.writeInt(target); 112 } 113 } 114 } 115 116 protected void annotateInstruction(AnnotatedOutput out, int currentCodeAddress) { 117 out.annotate(getSize(currentCodeAddress)*2, "[0x" + Integer.toHexString(currentCodeAddress) + "] " + 118 "sparse-switch-data instruction"); 119 } 120 121 public void updateTarget(int targetIndex, int targetAddressOffset) { 122 targets[targetIndex] = targetAddressOffset; 123 } 124 125 public Format getFormat() { 126 return Format.SparseSwitchData; 127 } 128 129 public int getTargetCount() { 130 return targets.length; 131 } 132 133 public int[] getTargets() { 134 return targets; 135 } 136 137 public int[] getKeys() { 138 return keys; 139 } 140 141 public static class SparseSwitchTarget { 142 public int key; 143 public int targetAddressOffset; 144 } 145 146 public Iterator<SparseSwitchTarget> iterateKeysAndTargets() { 147 return new Iterator<SparseSwitchTarget>() { 148 final int targetCount = getTargetCount(); 149 int i = 0; 150 151 SparseSwitchTarget sparseSwitchTarget = new SparseSwitchTarget(); 152 153 public boolean hasNext() { 154 return i<targetCount; 155 } 156 157 public SparseSwitchTarget next() { 158 sparseSwitchTarget.key = keys[i]; 159 sparseSwitchTarget.targetAddressOffset = targets[i]; 160 i++; 161 return sparseSwitchTarget; 162 } 163 164 public void remove() { 165 } 166 }; 167 } 168 169 private static class Factory implements Instruction.InstructionFactory { 170 public Instruction makeInstruction(DexFile dexFile, Opcode opcode, byte[] buffer, int bufferIndex) { 171 if (opcode != Opcode.NOP) { 172 throw new RuntimeException("The opcode for a SparseSwitchDataPseudoInstruction must be NOP"); 173 } 174 return new SparseSwitchDataPseudoInstruction(buffer, bufferIndex); 175 } 176 } 177} 178