1 /*
2  * Copyright (C) 2017 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 ART_LIBDEXFILE_DEX_DEX_FILE_REFERENCE_H_
18 #define ART_LIBDEXFILE_DEX_DEX_FILE_REFERENCE_H_
19 
20 #include <cstddef>
21 #include <cstdint>
22 #include <utility>
23 
24 namespace art {
25 
26 class DexFile;
27 
28 class DexFileReference {
29  public:
DexFileReference(const DexFile * file,uint32_t idx)30   DexFileReference(const DexFile* file, uint32_t idx) : dex_file(file), index(idx) {}
31   const DexFile* dex_file;
32   uint32_t index;
33 
34   struct Comparator {
operatorComparator35     bool operator()(const DexFileReference& a, const DexFileReference& b) const {
36       if (a.dex_file != b.dex_file) {
37         return a.dex_file < b.dex_file;
38       }
39       return a.index < b.index;
40     }
41   };
42 };
43 
44 // Default comparators, compares the indices, not the backing data.
45 inline bool operator<(const DexFileReference& a, const DexFileReference& b) {
46   return DexFileReference::Comparator()(a, b);
47 }
48 inline bool operator==(const DexFileReference& a, const DexFileReference& b) {
49   return a.dex_file == b.dex_file && a.index == b.index;
50 }
51 inline bool operator!=(const DexFileReference& a, const DexFileReference& b) {
52   return !(a == b);
53 }
54 
55 }  // namespace art
56 
57 namespace std {
58 // Hash implementation used for std::set/std::map. Simply xor the hash of the dex-file and index
59 template <>
60 struct hash<art::DexFileReference> {
61   size_t operator()(const art::DexFileReference& ref) const {
62     return hash<decltype(ref.dex_file)>()(ref.dex_file) ^
63            hash<decltype(ref.index)>()(ref.index);
64   }
65 };
66 }  // namespace std
67 
68 #endif  // ART_LIBDEXFILE_DEX_DEX_FILE_REFERENCE_H_
69