SparseSwitchMethodItem.java revision e00d96c438364844a5c87797119e8770d8ad1f67 
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.baksmali.Adaptors.Format;
30
31import org.jf.baksmali.Adaptors.LabelMethodItem;
32import org.jf.baksmali.Adaptors.MethodDefinition;
33import org.jf.util.IndentingWriter;
34import org.jf.baksmali.Renderers.IntegerRenderer;
35import org.jf.dexlib.Code.Format.SparseSwitchDataPseudoInstruction;
36import org.jf.dexlib.CodeItem;
37
38import java.io.IOException;
39import java.util.ArrayList;
40import java.util.Iterator;
41import java.util.List;
42
43public class SparseSwitchMethodItem extends InstructionMethodItem<SparseSwitchDataPseudoInstruction> {
44    private final List<SparseSwitchTarget> targets;
45
46    public SparseSwitchMethodItem(MethodDefinition methodDefinition, CodeItem codeItem, int codeAddress,
47                                  SparseSwitchDataPseudoInstruction instruction) {
48        super(codeItem, codeAddress, instruction);
49
50        int baseCodeAddress = methodDefinition.getSparseSwitchBaseAddress(codeAddress);
51
52        targets = new ArrayList<SparseSwitchTarget>();
53        Iterator<SparseSwitchDataPseudoInstruction.SparseSwitchTarget> iterator = instruction.iterateKeysAndTargets();
54        if (baseCodeAddress >= 0) {
55            while (iterator.hasNext()) {
56                SparseSwitchDataPseudoInstruction.SparseSwitchTarget target = iterator.next();
57                SparseSwitchLabelTarget sparseSwitchLabelTarget = new SparseSwitchLabelTarget();
58                sparseSwitchLabelTarget.Key = target.key;
59
60                LabelMethodItem label = new LabelMethodItem(baseCodeAddress + target.targetAddressOffset, "sswitch_");
61                label = methodDefinition.getLabelCache().internLabel(label);
62                sparseSwitchLabelTarget.Target = label;
63
64                targets.add(sparseSwitchLabelTarget);
65            }
66        } else {
67            //if we couldn't determine a base address, just use relative offsets rather than labels
68            while (iterator.hasNext()) {
69                SparseSwitchDataPseudoInstruction.SparseSwitchTarget target = iterator.next();
70                SparseSwitchOffsetTarget sparseSwitchOffsetTarget = new SparseSwitchOffsetTarget();
71                sparseSwitchOffsetTarget.Key = target.key;
72
73                sparseSwitchOffsetTarget.Target = target.targetAddressOffset;
74                targets.add(sparseSwitchOffsetTarget);
75            }
76        }
77    }
78
79    @Override
80    public boolean writeTo(IndentingWriter writer) throws IOException {
81        writer.write(".sparse-switch\n");
82        writer.indent(4);
83        for (SparseSwitchTarget target: targets) {
84            IntegerRenderer.writeTo(writer, target.Key);
85            writer.write(" -> ");
86            target.writeTargetTo(writer);
87            writer.write('\n');
88        }
89        writer.deindent(4);
90        writer.write(".end sparse-switch");
91        return true;
92    }
93
94    private static abstract class SparseSwitchTarget {
95        public int Key;
96        public abstract void writeTargetTo(IndentingWriter writer) throws IOException;
97    }
98
99    private static class SparseSwitchLabelTarget extends SparseSwitchTarget {
100        public LabelMethodItem Target;
101        public void writeTargetTo(IndentingWriter writer) throws IOException {
102            Target.writeTo(writer);
103        }
104    }
105
106    private static class SparseSwitchOffsetTarget extends SparseSwitchTarget {
107        public int Target;
108        public void writeTargetTo(IndentingWriter writer) throws IOException {
109            if (Target >= 0) {
110                writer.write('+');
111            }
112            writer.printSignedIntAsDec(Target);
113        }
114    }
115}
116