1/*
2 * Copyright (C) 2015 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef AAPT_IO_DATA_H
18#define AAPT_IO_DATA_H
19
20#include <utils/FileMap.h>
21
22#include <memory>
23
24namespace aapt {
25namespace io {
26
27/**
28 * Interface for a block of contiguous memory. An instance of this interface owns the data.
29 */
30class IData {
31public:
32    virtual ~IData() = default;
33
34    virtual const void* data() const = 0;
35    virtual size_t size() const = 0;
36};
37
38/**
39 * Implementation of IData that exposes a memory mapped file. The mmapped file is owned by this
40 * object.
41 */
42class MmappedData : public IData {
43public:
44    explicit MmappedData(android::FileMap&& map) : mMap(std::forward<android::FileMap>(map)) {
45    }
46
47    const void* data() const override {
48        return mMap.getDataPtr();
49    }
50
51    size_t size() const override {
52        return mMap.getDataLength();
53    }
54
55private:
56    android::FileMap mMap;
57};
58
59/**
60 * Implementation of IData that exposes a block of memory that was malloc'ed (new'ed). The
61 * memory is owned by this object.
62 */
63class MallocData : public IData {
64public:
65    MallocData(std::unique_ptr<const uint8_t[]> data, size_t size) :
66            mData(std::move(data)), mSize(size) {
67    }
68
69    const void* data() const override {
70        return mData.get();
71    }
72
73    size_t size() const override {
74        return mSize;
75    }
76
77private:
78    std::unique_ptr<const uint8_t[]> mData;
79    size_t mSize;
80};
81
82/**
83 * When mmap fails because the file has length 0, we use the EmptyData to simulate data of length 0.
84 */
85class EmptyData : public IData {
86public:
87    const void* data() const override {
88        static const uint8_t d = 0;
89        return &d;
90    }
91
92    size_t size() const override {
93        return 0u;
94    }
95};
96
97} // namespace io
98} // namespace aapt
99
100#endif /* AAPT_IO_DATA_H */
101