1 /* 2 * Copyright (C) 2015 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_NAME_MANGLER_H 18 #define AAPT_NAME_MANGLER_H 19 20 #include <set> 21 #include <string> 22 23 #include "Resource.h" 24 25 namespace aapt { 26 27 struct NameManglerPolicy { 28 /** 29 * Represents the package we are trying to build. References pointing 30 * to this package are not mangled, and mangled references inherit this 31 * package name. 32 */ 33 std::string target_package_name; 34 35 /** 36 * We must know which references to mangle, and which to keep (android vs. 37 * com.android.support). 38 */ 39 std::set<std::string> packages_to_mangle; 40 }; 41 42 class NameMangler { 43 public: NameMangler(NameManglerPolicy policy)44 explicit NameMangler(NameManglerPolicy policy) : policy_(policy) {} 45 MangleName(const ResourceName & name)46 std::optional<ResourceName> MangleName(const ResourceName& name) { 47 if (policy_.target_package_name == name.package || 48 policy_.packages_to_mangle.count(name.package) == 0) { 49 return {}; 50 } 51 52 std::string mangled_entry_name = MangleEntry(name.package, name.entry); 53 return ResourceName(policy_.target_package_name, name.type, 54 mangled_entry_name); 55 } 56 ShouldMangle(const std::string & package)57 bool ShouldMangle(const std::string& package) const { 58 if (package.empty() || policy_.target_package_name == package) { 59 return false; 60 } 61 return policy_.packages_to_mangle.count(package) != 0; 62 } 63 GetTargetPackageName()64 const std::string& GetTargetPackageName() const { return policy_.target_package_name; } 65 66 /** 67 * Returns a mangled name that is a combination of `name` and `package`. 68 * The mangled name should contain symbols that are illegal to define in XML, 69 * so that there will never be name mangling collisions. 70 */ MangleEntry(const std::string & package,const std::string & name)71 static std::string MangleEntry(const std::string& package, const std::string& name) { 72 return package + "$" + name; 73 } 74 75 /** 76 * Unmangles the name in `outName`, storing the correct name back in `outName` 77 * and the package in `outPackage`. Returns true if the name was unmangled or 78 * false if the name was never mangled to begin with. 79 */ Unmangle(std::string * out_name,std::string * out_package)80 static bool Unmangle(std::string* out_name, std::string* out_package) { 81 size_t pivot = out_name->find('$'); 82 if (pivot == std::string::npos) { 83 return false; 84 } 85 86 out_package->assign(out_name->data(), pivot); 87 std::string new_name = out_name->substr(pivot + 1); 88 *out_name = std::move(new_name); 89 return true; 90 } 91 92 private: 93 NameManglerPolicy policy_; 94 }; 95 96 } // namespace aapt 97 98 #endif // AAPT_NAME_MANGLER_H 99