ResourceValues.h revision 769de98f2dd41bfe39a1c9f76aefd1ad58942733
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_RESOURCE_VALUES_H 18#define AAPT_RESOURCE_VALUES_H 19 20#include "Resource.h" 21#include "StringPool.h" 22 23#include <array> 24#include <androidfw/ResourceTypes.h> 25#include <ostream> 26#include <vector> 27 28namespace aapt { 29 30struct ValueVisitor; 31struct ConstValueVisitor; 32struct ValueVisitorArgs; 33 34/** 35 * A resource value. This is an all-encompassing representation 36 * of Item and Map and their subclasses. The way to do 37 * type specific operations is to check the Value's type() and 38 * cast it to the appropriate subclass. This isn't super clean, 39 * but it is the simplest strategy. 40 */ 41struct Value { 42 /** 43 * Whether or not this is an Item. 44 */ 45 virtual bool isItem() const; 46 47 /** 48 * Whether this value is weak and can be overriden without 49 * warning or error. Default for base class is false. 50 */ 51 virtual bool isWeak() const; 52 53 /** 54 * Calls the appropriate overload of ValueVisitor. 55 */ 56 virtual void accept(ValueVisitor& visitor, ValueVisitorArgs&& args) = 0; 57 58 /** 59 * Const version of accept(). 60 */ 61 virtual void accept(ConstValueVisitor& visitor, ValueVisitorArgs&& args) const = 0; 62 63 /** 64 * Clone the value. 65 */ 66 virtual Value* clone(StringPool* newPool) const = 0; 67 68 /** 69 * Human readable printout of this value. 70 */ 71 virtual void print(std::ostream& out) const = 0; 72}; 73 74/** 75 * Inherit from this to get visitor accepting implementations for free. 76 */ 77template <typename Derived> 78struct BaseValue : public Value { 79 virtual void accept(ValueVisitor& visitor, ValueVisitorArgs&& args) override; 80 virtual void accept(ConstValueVisitor& visitor, ValueVisitorArgs&& args) const override; 81}; 82 83/** 84 * A resource item with a single value. This maps to android::ResTable_entry. 85 */ 86struct Item : public Value { 87 /** 88 * An Item is, of course, an Item. 89 */ 90 virtual bool isItem() const override; 91 92 /** 93 * Clone the Item. 94 */ 95 virtual Item* clone(StringPool* newPool) const override = 0; 96 97 /** 98 * Fills in an android::Res_value structure with this Item's binary representation. 99 * Returns false if an error ocurred. 100 */ 101 virtual bool flatten(android::Res_value& outValue) const = 0; 102}; 103 104/** 105 * Inherit from this to get visitor accepting implementations for free. 106 */ 107template <typename Derived> 108struct BaseItem : public Item { 109 virtual void accept(ValueVisitor& visitor, ValueVisitorArgs&& args) override; 110 virtual void accept(ConstValueVisitor& visitor, ValueVisitorArgs&& args) const override; 111}; 112 113/** 114 * A reference to another resource. This maps to android::Res_value::TYPE_REFERENCE. 115 * 116 * A reference can be symbolic (with the name set to a valid resource name) or be 117 * numeric (the id is set to a valid resource ID). 118 */ 119struct Reference : public BaseItem<Reference> { 120 enum class Type { 121 kResource, 122 kAttribute, 123 }; 124 125 ResourceName name; 126 ResourceId id; 127 Reference::Type referenceType; 128 bool privateReference = false; 129 130 Reference(); 131 Reference(const ResourceNameRef& n, Type type = Type::kResource); 132 Reference(const ResourceId& i, Type type = Type::kResource); 133 134 bool flatten(android::Res_value& outValue) const override; 135 Reference* clone(StringPool* newPool) const override; 136 void print(std::ostream& out) const override; 137}; 138 139/** 140 * An ID resource. Has no real value, just a place holder. 141 */ 142struct Id : public BaseItem<Id> { 143 bool isWeak() const override; 144 bool flatten(android::Res_value& out) const override; 145 Id* clone(StringPool* newPool) const override; 146 void print(std::ostream& out) const override; 147}; 148 149/** 150 * A raw, unprocessed string. This may contain quotations, 151 * escape sequences, and whitespace. This shall *NOT* 152 * end up in the final resource table. 153 */ 154struct RawString : public BaseItem<RawString> { 155 StringPool::Ref value; 156 157 RawString(const StringPool::Ref& ref); 158 159 bool flatten(android::Res_value& outValue) const override; 160 RawString* clone(StringPool* newPool) const override; 161 void print(std::ostream& out) const override; 162}; 163 164struct String : public BaseItem<String> { 165 StringPool::Ref value; 166 167 String(const StringPool::Ref& ref); 168 169 bool flatten(android::Res_value& outValue) const override; 170 String* clone(StringPool* newPool) const override; 171 void print(std::ostream& out) const override; 172}; 173 174struct StyledString : public BaseItem<StyledString> { 175 StringPool::StyleRef value; 176 177 StyledString(const StringPool::StyleRef& ref); 178 179 bool flatten(android::Res_value& outValue) const override; 180 StyledString* clone(StringPool* newPool) const override; 181 void print(std::ostream& out) const override; 182}; 183 184struct FileReference : public BaseItem<FileReference> { 185 StringPool::Ref path; 186 187 FileReference() = default; 188 FileReference(const StringPool::Ref& path); 189 190 bool flatten(android::Res_value& outValue) const override; 191 FileReference* clone(StringPool* newPool) const override; 192 void print(std::ostream& out) const override; 193}; 194 195/** 196 * Represents any other android::Res_value. 197 */ 198struct BinaryPrimitive : public BaseItem<BinaryPrimitive> { 199 android::Res_value value; 200 201 BinaryPrimitive() = default; 202 BinaryPrimitive(const android::Res_value& val); 203 204 bool flatten(android::Res_value& outValue) const override; 205 BinaryPrimitive* clone(StringPool* newPool) const override; 206 void print(std::ostream& out) const override; 207}; 208 209/** 210 * Sentinel value that should be ignored in the final output. 211 * Mainly used as a placeholder for public entries with no 212 * values defined yet. 213 */ 214struct Sentinel : public BaseItem<Sentinel> { 215 bool isWeak() const override; 216 bool flatten(android::Res_value& outValue) const override; 217 Sentinel* clone(StringPool* newPool) const override; 218 void print(std::ostream& out) const override; 219}; 220 221struct Attribute : public BaseValue<Attribute> { 222 struct Symbol { 223 Reference symbol; 224 uint32_t value; 225 }; 226 227 bool weak; 228 uint32_t typeMask; 229 uint32_t minInt; 230 uint32_t maxInt; 231 std::vector<Symbol> symbols; 232 233 Attribute(bool w, uint32_t t = 0u); 234 235 bool isWeak() const override; 236 virtual Attribute* clone(StringPool* newPool) const override; 237 virtual void print(std::ostream& out) const override; 238}; 239 240struct Style : public BaseValue<Style> { 241 struct Entry { 242 Reference key; 243 std::unique_ptr<Item> value; 244 }; 245 246 bool weak; 247 Reference parent; 248 std::vector<Entry> entries; 249 250 Style(bool weak); 251 bool isWeak() const override; 252 Style* clone(StringPool* newPool) const override; 253 void print(std::ostream& out) const override; 254}; 255 256struct Array : public BaseValue<Array> { 257 std::vector<std::unique_ptr<Item>> items; 258 259 Array* clone(StringPool* newPool) const override; 260 void print(std::ostream& out) const override; 261}; 262 263struct Plural : public BaseValue<Plural> { 264 enum { 265 Zero = 0, 266 One, 267 Two, 268 Few, 269 Many, 270 Other, 271 Count 272 }; 273 274 std::array<std::unique_ptr<Item>, Count> values; 275 276 Plural* clone(StringPool* newPool) const override; 277 void print(std::ostream& out) const override; 278}; 279 280struct Styleable : public BaseValue<Styleable> { 281 std::vector<Reference> entries; 282 283 Styleable* clone(StringPool* newPool) const override; 284 void print(std::ostream& out) const override; 285}; 286 287/** 288 * Stream operator for printing Value objects. 289 */ 290inline ::std::ostream& operator<<(::std::ostream& out, const Value& value) { 291 value.print(out); 292 return out; 293} 294 295/** 296 * The argument object that gets passed through the value 297 * back to the ValueVisitor. Subclasses of ValueVisitor should 298 * subclass ValueVisitorArgs to contain the data they need 299 * to operate. 300 */ 301struct ValueVisitorArgs {}; 302 303/** 304 * Visits a value and runs the appropriate method based on its type. 305 */ 306struct ValueVisitor { 307 virtual void visit(Reference& reference, ValueVisitorArgs& args) { 308 visitItem(reference, args); 309 } 310 311 virtual void visit(RawString& string, ValueVisitorArgs& args) { 312 visitItem(string, args); 313 } 314 315 virtual void visit(String& string, ValueVisitorArgs& args) { 316 visitItem(string, args); 317 } 318 319 virtual void visit(StyledString& string, ValueVisitorArgs& args) { 320 visitItem(string, args); 321 } 322 323 virtual void visit(FileReference& file, ValueVisitorArgs& args) { 324 visitItem(file, args); 325 } 326 327 virtual void visit(Id& id, ValueVisitorArgs& args) { 328 visitItem(id, args); 329 } 330 331 virtual void visit(BinaryPrimitive& primitive, ValueVisitorArgs& args) { 332 visitItem(primitive, args); 333 } 334 335 virtual void visit(Sentinel& sentinel, ValueVisitorArgs& args) { 336 visitItem(sentinel, args); 337 } 338 339 virtual void visit(Attribute& attr, ValueVisitorArgs& args) {} 340 virtual void visit(Style& style, ValueVisitorArgs& args) {} 341 virtual void visit(Array& array, ValueVisitorArgs& args) {} 342 virtual void visit(Plural& array, ValueVisitorArgs& args) {} 343 virtual void visit(Styleable& styleable, ValueVisitorArgs& args) {} 344 345 virtual void visitItem(Item& item, ValueVisitorArgs& args) {} 346}; 347 348/** 349 * Const version of ValueVisitor. 350 */ 351struct ConstValueVisitor { 352 virtual void visit(const Reference& reference, ValueVisitorArgs& args) { 353 visitItem(reference, args); 354 } 355 356 virtual void visit(const RawString& string, ValueVisitorArgs& args) { 357 visitItem(string, args); 358 } 359 360 virtual void visit(const String& string, ValueVisitorArgs& args) { 361 visitItem(string, args); 362 } 363 364 virtual void visit(const StyledString& string, ValueVisitorArgs& args) { 365 visitItem(string, args); 366 } 367 368 virtual void visit(const FileReference& file, ValueVisitorArgs& args) { 369 visitItem(file, args); 370 } 371 372 virtual void visit(const Id& id, ValueVisitorArgs& args) { 373 visitItem(id, args); 374 } 375 376 virtual void visit(const BinaryPrimitive& primitive, ValueVisitorArgs& args) { 377 visitItem(primitive, args); 378 } 379 380 virtual void visit(const Sentinel& sentinel, ValueVisitorArgs& args) { 381 visitItem(sentinel, args); 382 } 383 384 virtual void visit(const Attribute& attr, ValueVisitorArgs& args) {} 385 virtual void visit(const Style& style, ValueVisitorArgs& args) {} 386 virtual void visit(const Array& array, ValueVisitorArgs& args) {} 387 virtual void visit(const Plural& array, ValueVisitorArgs& args) {} 388 virtual void visit(const Styleable& styleable, ValueVisitorArgs& args) {} 389 390 virtual void visitItem(const Item& item, ValueVisitorArgs& args) {} 391}; 392 393/** 394 * Convenience Visitor that forwards a specific type to a function. 395 * Args are not used as the function can bind variables. Do not use 396 * directly, use the wrapper visitFunc() method. 397 */ 398template <typename T, typename TFunc> 399struct ValueVisitorFunc : ValueVisitor { 400 TFunc func; 401 402 ValueVisitorFunc(TFunc f) : func(f) { 403 } 404 405 void visit(T& value, ValueVisitorArgs&) override { 406 func(value); 407 } 408}; 409 410/** 411 * Const version of ValueVisitorFunc. 412 */ 413template <typename T, typename TFunc> 414struct ConstValueVisitorFunc : ConstValueVisitor { 415 TFunc func; 416 417 ConstValueVisitorFunc(TFunc f) : func(f) { 418 } 419 420 void visit(const T& value, ValueVisitorArgs&) override { 421 func(value); 422 } 423}; 424 425template <typename T, typename TFunc> 426void visitFunc(Value& value, TFunc f) { 427 ValueVisitorFunc<T, TFunc> visitor(f); 428 value.accept(visitor, ValueVisitorArgs{}); 429} 430 431template <typename T, typename TFunc> 432void visitFunc(const Value& value, TFunc f) { 433 ConstValueVisitorFunc<T, TFunc> visitor(f); 434 value.accept(visitor, ValueVisitorArgs{}); 435} 436 437template <typename Derived> 438void BaseValue<Derived>::accept(ValueVisitor& visitor, ValueVisitorArgs&& args) { 439 visitor.visit(static_cast<Derived&>(*this), args); 440} 441 442template <typename Derived> 443void BaseValue<Derived>::accept(ConstValueVisitor& visitor, ValueVisitorArgs&& args) const { 444 visitor.visit(static_cast<const Derived&>(*this), args); 445} 446 447template <typename Derived> 448void BaseItem<Derived>::accept(ValueVisitor& visitor, ValueVisitorArgs&& args) { 449 visitor.visit(static_cast<Derived&>(*this), args); 450} 451 452template <typename Derived> 453void BaseItem<Derived>::accept(ConstValueVisitor& visitor, ValueVisitorArgs&& args) const { 454 visitor.visit(static_cast<const Derived&>(*this), args); 455} 456 457} // namespace aapt 458 459#endif // AAPT_RESOURCE_VALUES_H 460