1 /*
2  * Copyright (C) 2011 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_RUNTIME_DEX_METHOD_ITERATOR_H_
18 #define ART_RUNTIME_DEX_METHOD_ITERATOR_H_
19 
20 #include <vector>
21 
22 #include "dex_file.h"
23 
24 namespace art {
25 
26 class DexMethodIterator {
27  public:
DexMethodIterator(const std::vector<const DexFile * > & dex_files)28   explicit DexMethodIterator(const std::vector<const DexFile*>& dex_files)
29       : dex_files_(dex_files),
30         found_next_(false),
31         dex_file_index_(0),
32         class_def_index_(0),
33         class_def_(nullptr),
34         class_data_(nullptr),
35         direct_method_(false) {
36     CHECK_NE(0U, dex_files_.size());
37   }
38 
HasNext()39   bool HasNext() {
40     if (found_next_) {
41       return true;
42     }
43     while (true) {
44       // End of DexFiles, we are done.
45       if (dex_file_index_ == dex_files_.size()) {
46         return false;
47       }
48       if (class_def_index_ == GetDexFileInternal().NumClassDefs()) {
49         // End of this DexFile, advance and retry.
50         class_def_index_ = 0;
51         dex_file_index_++;
52         continue;
53       }
54       if (class_def_ == nullptr) {
55         class_def_ = &GetDexFileInternal().GetClassDef(class_def_index_);
56       }
57       if (class_data_ == nullptr) {
58         class_data_ = GetDexFileInternal().GetClassData(*class_def_);
59         if (class_data_ == nullptr) {
60           // empty class, such as a marker interface
61           // End of this class, advance and retry.
62           class_def_ = nullptr;
63           class_def_index_++;
64           continue;
65         }
66       }
67       if (it_.get() == nullptr) {
68         it_.reset(new ClassDataItemIterator(GetDexFileInternal(), class_data_));
69         // Skip fields
70         while (GetIterator().HasNextStaticField()) {
71           GetIterator().Next();
72         }
73         while (GetIterator().HasNextInstanceField()) {
74           GetIterator().Next();
75         }
76         direct_method_ = true;
77       }
78       if (direct_method_ && GetIterator().HasNextDirectMethod()) {
79         // Found method
80         found_next_ = true;
81         return true;
82       }
83       direct_method_ = false;
84       if (GetIterator().HasNextVirtualMethod()) {
85         // Found method
86         found_next_ = true;
87         return true;
88       }
89       // End of this class, advance and retry.
90       DCHECK(!GetIterator().HasNext());
91       it_.reset(nullptr);
92       class_data_ = nullptr;
93       class_def_ = nullptr;
94       class_def_index_++;
95     }
96   }
97 
Next()98   void Next() {
99     found_next_ = false;
100     if (it_.get() != nullptr) {
101       // Advance to next method if we currently are looking at a class.
102       GetIterator().Next();
103     }
104   }
105 
GetDexFile()106   const DexFile& GetDexFile() {
107     CHECK(HasNext());
108     return GetDexFileInternal();
109   }
110 
GetMemberIndex()111   uint32_t GetMemberIndex() {
112     CHECK(HasNext());
113     return GetIterator().GetMemberIndex();
114   }
115 
GetInvokeType()116   InvokeType GetInvokeType() {
117     CHECK(HasNext());
118     CHECK(class_def_ != nullptr);
119     return GetIterator().GetMethodInvokeType(*class_def_);
120   }
121 
122  private:
GetIterator()123   ClassDataItemIterator& GetIterator() const {
124     CHECK(it_.get() != nullptr);
125     return *it_.get();
126   }
127 
GetDexFileInternal()128   const DexFile& GetDexFileInternal() const {
129     CHECK_LT(dex_file_index_, dex_files_.size());
130     const DexFile* dex_file = dex_files_[dex_file_index_];
131     CHECK(dex_file != nullptr);
132     return *dex_file;
133   }
134 
135   const std::vector<const DexFile*>& dex_files_;
136 
137   bool found_next_;
138 
139   uint32_t dex_file_index_;
140   uint32_t class_def_index_;
141   const DexFile::ClassDef* class_def_;
142   const uint8_t* class_data_;
143   std::unique_ptr<ClassDataItemIterator> it_;
144   bool direct_method_;
145 };
146 
147 }  // namespace art
148 
149 #endif  // ART_RUNTIME_DEX_METHOD_ITERATOR_H_
150