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;
30
31import org.jf.dexlib.Code.Format.Format;
32import org.jf.dexlib.DexFile;
33import org.jf.dexlib.Util.AnnotatedOutput;
34
35public abstract class Instruction {
36    public final Opcode opcode;
37
38    /**
39     * Returns the size of this instruction in code blocks, assuming the instruction is located at the given address
40     * @param codeAddress the code address where the instruction is located
41     * @return The size of this instruction in code blocks
42     **/
43    public int getSize(int codeAddress) {
44        return opcode.format.size/2;
45    }
46
47    protected Instruction(Opcode opcode) {
48        this.opcode = opcode;
49    }
50
51    public abstract Format getFormat();
52
53    public int write(AnnotatedOutput out, int currentCodeAddress) {
54        if (out.annotates()) {
55            annotateInstruction(out, currentCodeAddress);
56        }
57        writeInstruction(out, currentCodeAddress);
58        return currentCodeAddress + getSize(currentCodeAddress);
59    }
60
61    protected void annotateInstruction(AnnotatedOutput out, int currentCodeAddress) {
62        out.annotate(getSize(currentCodeAddress)*2, "[0x" + Integer.toHexString(currentCodeAddress) + "] " +
63                opcode.name + " instruction");
64    }
65
66    protected abstract void writeInstruction(AnnotatedOutput out, int currentCodeAddress);
67
68    public static interface InstructionFactory {
69        public Instruction makeInstruction(DexFile dexFile, Opcode opcode, byte[] buffer, int bufferIndex);
70    }
71}
72