1 /*
2  * Copyright (C) 2018 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  * Header file of an in-memory representation of DEX files.
17  */
18 
19 #ifndef ART_DEXLAYOUT_DEX_CONTAINER_H_
20 #define ART_DEXLAYOUT_DEX_CONTAINER_H_
21 
22 #include <vector>
23 
24 namespace art {
25 
26 // Dex container holds the artifacts produced by dexlayout and contains up to two sections: a main
27 // section and a data section.
28 // This container may also hold metadata used for multi dex deduplication in the future.
29 class DexContainer {
30  public:
~DexContainer()31   virtual ~DexContainer() {}
32 
33   class Section {
34    public:
~Section()35     virtual ~Section() {}
36 
37     // Returns the start of the memory region.
38     virtual uint8_t* Begin() = 0;
39 
40     // Size in bytes.
41     virtual size_t Size() const = 0;
42 
43     // Resize the backing storage.
44     virtual void Resize(size_t size) = 0;
45 
46     // Clear the container.
47     virtual void Clear() = 0;
48 
49     // Release the data, clearing the container contents.
50     virtual std::vector<uint8_t> ReleaseData() = 0;
51 
52     // Returns the end of the memory region.
End()53     uint8_t* End() {
54       return Begin() + Size();
55     }
56   };
57 
58   // Vector backed section.
59   class VectorSection : public Section {
60    public:
~VectorSection()61     virtual ~VectorSection() {}
62 
Begin()63     uint8_t* Begin() override {
64       return &data_[0];
65     }
66 
Size()67     size_t Size() const override {
68       return data_.size();
69     }
70 
Resize(size_t size)71     void Resize(size_t size) override {
72       data_.resize(size, 0u);
73     }
74 
Clear()75     void Clear() override {
76       data_.clear();
77     }
78 
ReleaseData()79     std::vector<uint8_t> ReleaseData() override {
80       std::vector<uint8_t> temp;
81       temp.swap(data_);
82       return temp;
83     }
84 
85    private:
86     std::vector<uint8_t> data_;
87   };
88 
89   virtual Section* GetMainSection() = 0;
90   virtual Section* GetDataSection() = 0;
91   virtual bool IsCompactDexContainer() const = 0;
92 };
93 
94 }  // namespace art
95 
96 #endif  // ART_DEXLAYOUT_DEX_CONTAINER_H_
97