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 AAPT_LINKER_XMLCOMPATVERSIONER_H
18 #define AAPT_LINKER_XMLCOMPATVERSIONER_H
19 
20 #include <set>
21 #include <unordered_map>
22 #include <vector>
23 
24 #include "android-base/macros.h"
25 
26 #include "Resource.h"
27 #include "SdkConstants.h"
28 #include "process/IResourceTableConsumer.h"
29 #include "util/Util.h"
30 #include "xml/XmlDom.h"
31 
32 namespace aapt {
33 
34 class IDegradeRule;
35 
36 struct DegradeResult {
37   xml::Attribute attr;
38   ApiVersion attr_api_version;
39 };
40 
41 class IDegradeRule {
42  public:
43   IDegradeRule() = default;
44   virtual ~IDegradeRule() = default;
45 
46   virtual std::vector<DegradeResult> Degrade(const xml::Element& src_el,
47                                              const xml::Attribute& src_attr,
48                                              StringPool* out_string_pool) const = 0;
49 
50  private:
51   DISALLOW_COPY_AND_ASSIGN(IDegradeRule);
52 };
53 
54 class XmlCompatVersioner {
55  public:
56   using Rules = std::unordered_map<ResourceId, std::unique_ptr<IDegradeRule>>;
57 
58   explicit XmlCompatVersioner(const Rules* rules);
59 
60   std::vector<std::unique_ptr<xml::XmlResource>> Process(IAaptContext* context,
61                                                          xml::XmlResource* doc,
62                                                          util::Range<ApiVersion> api_range);
63 
64  private:
65   DISALLOW_COPY_AND_ASSIGN(XmlCompatVersioner);
66 
67   std::unique_ptr<xml::XmlResource> ProcessDoc(ApiVersion target_api, ApiVersion max_api,
68                                                xml::XmlResource* doc,
69                                                std::set<ApiVersion>* out_apis_referenced);
70   void ProcessRule(const xml::Element& src_el, const xml::Attribute& src_attr,
71                    const ApiVersion& src_attr_version, const IDegradeRule* rule,
72                    const util::Range<ApiVersion>& api_range, bool generated, xml::Element* dst_el,
73                    std::set<ApiVersion>* out_apis_referenced, StringPool* out_string_pool);
74 
75   const Rules* rules_;
76 };
77 
78 struct ReplacementAttr {
79   std::string name;
80   ResourceId id;
81   Attribute attr;
82 };
83 
84 class DegradeToManyRule : public IDegradeRule {
85  public:
86   explicit DegradeToManyRule(std::vector<ReplacementAttr> attrs);
87   virtual ~DegradeToManyRule() = default;
88 
89   std::vector<DegradeResult> Degrade(const xml::Element& src_el, const xml::Attribute& src_attr,
90                                      StringPool* out_string_pool) const override;
91 
92  private:
93   DISALLOW_COPY_AND_ASSIGN(DegradeToManyRule);
94 
95   std::vector<ReplacementAttr> attrs_;
96 };
97 
98 }  // namespace aapt
99 
100 #endif  // AAPT_LINKER_XMLCOMPATVERSIONER_H
101