1/*
2 * Copyright 2013, 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
32package org.jf.dexlib2.builder;
33
34import org.jf.dexlib2.Opcode;
35import org.jf.dexlib2.iface.instruction.OffsetInstruction;
36import org.jf.util.ExceptionWithContext;
37
38import javax.annotation.Nonnull;
39
40public abstract class BuilderOffsetInstruction extends BuilderInstruction implements OffsetInstruction {
41    @Nonnull
42    protected final Label target;
43
44    public BuilderOffsetInstruction(@Nonnull Opcode opcode,
45                                    @Nonnull Label target) {
46        super(opcode);
47        this.target = target;
48    }
49
50    @Override public int getCodeOffset() {
51        int codeOffset = internalGetCodeOffset();
52        if (this.getCodeUnits() == 1) {
53            if (codeOffset < Byte.MIN_VALUE || codeOffset > Byte.MAX_VALUE) {
54                throw new ExceptionWithContext("Invalid instruction offset: %d. " +
55                        "Offset must be in [-128, 127]", codeOffset);
56            }
57        } else if (this.getCodeUnits() == 2) {
58            if (codeOffset < Short.MIN_VALUE || codeOffset > Short.MAX_VALUE) {
59                throw new ExceptionWithContext("Invalid instruction offset: %d. " +
60                        "Offset must be in [-32768, 32767]", codeOffset);
61            }
62        }
63        return codeOffset;
64    }
65
66
67    int internalGetCodeOffset() {
68        return target.getCodeAddress() - this.getLocation().getCodeAddress();
69    }
70
71    @Nonnull
72    public Label getTarget() {
73        return target;
74    }
75}
76