1 /*
2  * Copyright (c) 2017 VMware, Inc.
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 #pragma once
18 
19 #include <cstddef>
20 #include <iterator>
21 #include <map>
22 #include <memory>
23 #include <string>
24 #include <vector>
25 
26 #include "table_desc.h"
27 
28 namespace ebpf {
29 
30 typedef std::map<int, std::tuple<int, std::string, int, int, int, int, int, std::string, std::string>>
31         fake_fd_map_def;
32 
33 class TableStorageImpl;
34 class TableStorageIteratorImpl;
35 
36 class Path {
37  public:
38   static const std::string DELIM;
39   Path() = default;
40   Path(const Path &other) = default;
41   Path &operator=(const Path &other) = default;
Path(std::initializer_list<std::string> parts)42   Path(std::initializer_list<std::string> parts) {
43     size_t len = parts.size() * DELIM.size();
44     for (const auto &s : parts)
45       len += s.size();
46     path_.reserve(len);
47     for (const auto &s : parts)
48       path_ += DELIM + s;
49   }
to_string()50   const std::string &to_string() const { return path_; }
51 
52  private:
53   std::string path_;
54 };
55 
56 class TableStorage {
57  public:
58   /// iterator is an abstract class for traversing the map entries in a table
59   /// storage object.
60   class iterator {
61    private:
62     friend class TableStorage;
63     iterator(const iterator &);
64 
65    public:
66     typedef std::pair<const std::string, TableDesc> value_type;
67     typedef std::ptrdiff_t difference_type;
68     typedef value_type *pointer;
69     typedef value_type &reference;
70     typedef std::forward_iterator_tag iterator_category;
71     typedef iterator self_type;
72 
73     iterator();
74     iterator(std::unique_ptr<TableStorageIteratorImpl>);
75     ~iterator();
76     iterator(iterator &&);
77     iterator &operator=(iterator &&);
78     self_type &operator++();
79     self_type operator++(int);
80     bool operator==(const self_type &) const;
81     bool operator!=(const self_type &) const;
82     value_type &operator*() const;
83     pointer operator->() const;
84 
85    private:
86     std::unique_ptr<TableStorageIteratorImpl> impl_;
87   };
88 
89   TableStorage();
90   ~TableStorage();
91   void Init(std::unique_ptr<TableStorageImpl>);
92 
93   bool Find(const Path &path, TableStorage::iterator &result) const;
94   bool Insert(const Path &path, TableDesc &&desc);
95   bool Delete(const Path &path);
96   size_t DeletePrefix(const Path &path);
97 
98   void AddMapTypesVisitor(std::unique_ptr<MapTypesVisitor>);
99   void VisitMapType(TableDesc &desc, clang::ASTContext &C, clang::QualType key_type,
100                     clang::QualType leaf_type);
101   iterator begin();
102   iterator end();
103   iterator lower_bound(const Path &p);
104   iterator upper_bound(const Path &p);
105 
106  private:
107   std::unique_ptr<TableStorageImpl> impl_;
108   std::vector<std::unique_ptr<MapTypesVisitor>> visitors_;
109 };
110 
111 std::unique_ptr<TableStorage> createSharedTableStorage();
112 std::unique_ptr<TableStorage> createBpfFsTableStorage();
113 }
114