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| 1 // Copyright 2016 The Chromium Authors. All rights reserved. | |
| 2 // Use of this source code is governed by a BSD-style license that can be | |
| 3 // found in the LICENSE file. | |
| 4 | |
| 5 #ifndef MOJO_PUBLIC_CPP_BINDINGS_LIB_ARRAY_SERIALIZATION_TRAITS_H_ | |
| 6 #define MOJO_PUBLIC_CPP_BINDINGS_LIB_ARRAY_SERIALIZATION_TRAITS_H_ | |
| 7 | |
| 8 #include <stddef.h> | |
| 9 #include <string.h> // For |memcpy()|. | |
| 10 | |
| 11 #include <limits> | |
| 12 #include <type_traits> | |
| 13 #include <utility> | |
| 14 #include <vector> | |
| 15 | |
| 16 #include "base/logging.h" | |
| 17 #include "mojo/public/cpp/bindings/lib/array_internal.h" | |
| 18 #include "mojo/public/cpp/bindings/lib/serialization_forward.h" | |
| 19 #include "mojo/public/cpp/bindings/lib/template_util.h" | |
| 20 #include "mojo/public/cpp/bindings/lib/validation_errors.h" | |
| 21 | |
| 22 namespace WTF { | |
| 23 class String; | |
| 24 } | |
| 25 | |
| 26 namespace mojo { | |
| 27 namespace internal { | |
| 28 | |
| 29 enum class ArraySerializerType { | |
| 30 BOOLEAN, | |
| 31 // Except boolean. | |
| 32 POD, | |
| 33 HANDLE, | |
| 34 POINTER, | |
| 35 UNION | |
| 36 }; | |
| 37 | |
| 38 template <typename T> | |
| 39 struct GetArraySerializerType { | |
| 40 static const ArraySerializerType value = | |
| 41 IsUnionDataType<T>::value | |
| 42 ? ArraySerializerType::UNION | |
| 43 : (std::is_pointer<T>::value | |
| 44 ? ArraySerializerType::POINTER | |
| 45 : (IsHandle<T>::value ? ArraySerializerType::HANDLE | |
| 46 : (std::is_same<T, bool>::value | |
| 47 ? ArraySerializerType::BOOLEAN | |
| 48 : ArraySerializerType::POD))); | |
| 49 }; | |
| 50 | |
| 51 template <typename MojomType, | |
| 52 typename UserType, | |
| 53 ArraySerializerType type = | |
| 54 GetArraySerializerType<typename MojomType::Data_::Element>::value> | |
| 55 struct ArraySerializer; | |
| 56 | |
| 57 // Handles serialization and deserialization of arrays of pod types. | |
| 58 template <typename MojomType, typename UserType> | |
| 59 struct ArraySerializer<MojomType, UserType, ArraySerializerType::POD> { | |
| 60 using Data = typename MojomType::Data_; | |
| 61 using DataElement = typename Data::Element; | |
| 62 using Element = typename MojomType::Element; | |
| 63 using Traits = ArrayTraits<UserType>; | |
| 64 using UserElement = typename Traits::Element; | |
| 65 | |
| 66 static_assert(sizeof(Element) == sizeof(DataElement), | |
| 67 "Incorrect array serializer"); | |
| 68 static_assert(std::is_same<Element, UserElement>::value, | |
| 69 "Incorrect array serializer"); | |
| 70 | |
| 71 static size_t GetSerializedSize(const UserType& input, | |
| 72 SerializationContext* context) { | |
| 73 return sizeof(Data) + Align(Traits::GetSize(input) * sizeof(DataElement)); | |
| 74 } | |
| 75 | |
| 76 static void SerializeElements(UserType input, | |
| 77 Buffer* buf, | |
| 78 Data* output, | |
| 79 const ArrayValidateParams* validate_params, | |
| 80 SerializationContext* context) { | |
| 81 DCHECK(!validate_params->element_is_nullable) | |
| 82 << "Primitive type should be non-nullable"; | |
| 83 DCHECK(!validate_params->element_validate_params) | |
| 84 << "Primitive type should not have array validate params"; | |
| 85 | |
| 86 if (Traits::GetSize(input)) { | |
| 87 memcpy(output->storage(), Traits::GetData(input), | |
| 88 Traits::GetSize(input) * sizeof(DataElement)); | |
| 89 } | |
| 90 } | |
| 91 | |
| 92 static bool DeserializeElements(Data* input, | |
| 93 UserType* output, | |
| 94 SerializationContext* context) { | |
| 95 Traits::Resize(*output, input->size()); | |
| 96 if (input->size()) { | |
| 97 memcpy(Traits::GetData(*output), input->storage(), | |
| 98 input->size() * sizeof(DataElement)); | |
| 99 } | |
| 100 return true; | |
| 101 } | |
| 102 }; | |
| 103 | |
| 104 // Serializes and deserializes arrays of bools. | |
| 105 template <typename MojomType, typename UserType> | |
| 106 struct ArraySerializer<MojomType, UserType, ArraySerializerType::BOOLEAN> { | |
| 107 using Traits = ArrayTraits<UserType>; | |
| 108 using Data = typename MojomType::Data_; | |
| 109 | |
| 110 static_assert(std::is_same<bool, typename UserType::Element>::value, | |
| 111 "Incorrect array serializer"); | |
| 112 | |
| 113 static size_t GetSerializedSize(const UserType& input, | |
| 114 SerializationContext* context) { | |
| 115 return sizeof(Data) + Align((Traits::GetSize(input) + 7) / 8); | |
| 116 } | |
| 117 | |
| 118 static void SerializeElements(UserType input, | |
| 119 Buffer* buf, | |
| 120 Data* output, | |
| 121 const ArrayValidateParams* validate_params, | |
| 122 SerializationContext* context) { | |
| 123 DCHECK(!validate_params->element_is_nullable) | |
| 124 << "Primitive type should be non-nullable"; | |
| 125 DCHECK(!validate_params->element_validate_params) | |
| 126 << "Primitive type should not have array validate params"; | |
| 127 | |
| 128 // TODO(darin): Can this be a memcpy somehow instead of a bit-by-bit copy? | |
| 129 size_t size = Traits::GetSize(input); | |
| 130 for (size_t i = 0; i < size; ++i) | |
| 131 output->at(i) = Traits::GetAt(input, i); | |
| 132 } | |
| 133 static bool DeserializeElements(Data* input, | |
| 134 UserType* output, | |
| 135 SerializationContext* context) { | |
| 136 Traits::Resize(*output, input->size()); | |
| 137 // TODO(darin): Can this be a memcpy somehow instead of a bit-by-bit copy? | |
| 138 for (size_t i = 0; i < input->size(); ++i) | |
| 139 Traits::GetAt(*output, i) = input->at(i); | |
| 140 return true; | |
| 141 } | |
| 142 }; | |
| 143 | |
| 144 // Serializes and deserializes arrays of handles. | |
| 145 template <typename MojomType, typename UserType> | |
| 146 struct ArraySerializer<MojomType, UserType, ArraySerializerType::HANDLE> { | |
| 147 using Data = typename MojomType::Data_; | |
| 148 using DataElement = typename Data::Element; | |
| 149 using Element = typename MojomType::Element; | |
| 150 using Traits = ArrayTraits<UserType>; | |
| 151 using UserElement = typename Traits::Element; | |
| 152 | |
| 153 static_assert(std::is_same<Element, UserElement>::value, | |
| 154 "Incorrect array serializer"); | |
| 155 | |
| 156 static size_t GetSerializedSize(const UserType& input, | |
| 157 SerializationContext* context) { | |
| 158 return sizeof(Data) + Align(Traits::GetSize(input) * sizeof(DataElement)); | |
| 159 } | |
| 160 | |
| 161 static void SerializeElements(UserType input, | |
| 162 Buffer* buf, | |
| 163 Data* output, | |
| 164 const ArrayValidateParams* validate_params, | |
| 165 SerializationContext* context) { | |
| 166 DCHECK(!validate_params->element_validate_params) | |
| 167 << "Handle type should not have array validate params"; | |
| 168 | |
| 169 size_t size = Traits::GetSize(input); | |
| 170 for (size_t i = 0; i < size; ++i) { | |
| 171 // Transfer ownership of the handle. | |
| 172 output->at(i) = | |
| 173 context->handles.AddHandle(Traits::GetAt(input, i).release()); | |
| 174 MOJO_INTERNAL_DLOG_SERIALIZATION_WARNING( | |
| 175 !validate_params->element_is_nullable && !output->at(i).is_valid(), | |
| 176 VALIDATION_ERROR_UNEXPECTED_INVALID_HANDLE, | |
| 177 MakeMessageWithArrayIndex( | |
| 178 "invalid handle in array expecting valid handles", size, i)); | |
| 179 } | |
| 180 } | |
| 181 static bool DeserializeElements(Data* input, | |
| 182 UserType* output, | |
| 183 SerializationContext* context) { | |
| 184 using HandleType = typename Element::RawHandleType; | |
| 185 Traits::Resize(*output, input->size()); | |
| 186 for (size_t i = 0; i < input->size(); ++i) { | |
| 187 Traits::GetAt(*output, i) = MakeScopedHandle(HandleType( | |
| 188 context->handles.TakeHandle(input->at(i)).value())); | |
| 189 } | |
| 190 return true; | |
| 191 } | |
| 192 }; | |
| 193 | |
| 194 // This template must only apply to pointer mojo entity (strings, structs, | |
| 195 // arrays and maps). | |
| 196 template <typename MojomType, typename UserType> | |
| 197 struct ArraySerializer<MojomType, UserType, ArraySerializerType::POINTER> { | |
| 198 using Data = typename MojomType::Data_; | |
| 199 using DataElement = typename Data::Element; | |
| 200 using Element = typename MojomType::Element; | |
| 201 using Traits = ArrayTraits<UserType>; | |
| 202 using UserElement = typename Traits::Element; | |
| 203 | |
| 204 static size_t GetSerializedSize(const UserType& input, | |
| 205 SerializationContext* context) { | |
| 206 size_t element_count = Traits::GetSize(input); | |
| 207 size_t size = | |
| 208 sizeof(Data) + | |
| 209 element_count * | |
| 210 sizeof(Pointer<typename std::remove_pointer<DataElement>::type>); | |
| 211 for (size_t i = 0; i < element_count; ++i) | |
| 212 size += GetSerializedSize_(Traits::GetAt(input, i), context); | |
| 213 return size; | |
| 214 } | |
| 215 | |
| 216 static void SerializeElements(UserType input, | |
| 217 Buffer* buf, | |
| 218 Data* output, | |
| 219 const ArrayValidateParams* validate_params, | |
| 220 SerializationContext* context) { | |
| 221 size_t size = Traits::GetSize(input); | |
| 222 for (size_t i = 0; i < size; ++i) { | |
| 223 DataElement element; | |
| 224 SerializeCaller<Element>::Run( | |
| 225 std::move(Traits::GetAt(input, i)), buf, &element, | |
| 226 validate_params->element_validate_params, context); | |
| 227 output->at(i) = element; | |
| 228 MOJO_INTERNAL_DLOG_SERIALIZATION_WARNING( | |
| 229 !validate_params->element_is_nullable && !element, | |
| 230 VALIDATION_ERROR_UNEXPECTED_NULL_POINTER, | |
| 231 MakeMessageWithArrayIndex("null in array expecting valid pointers", | |
| 232 size, i)); | |
| 233 } | |
| 234 } | |
| 235 static bool DeserializeElements(Data* input, | |
| 236 UserType* output, | |
| 237 SerializationContext* context) { | |
| 238 bool success = true; | |
| 239 Traits::Resize(*output, input->size()); | |
| 240 for (size_t i = 0; i < input->size(); ++i) { | |
| 241 // Note that we rely on complete deserialization taking place in order to | |
| 242 // transfer ownership of all encoded handles. Therefore we don't | |
| 243 // short-circuit on failure here. | |
| 244 if (!Deserialize_(input->at(i), &Traits::GetAt(*output, i), context)) | |
| 245 success = false; | |
| 246 } | |
| 247 return success; | |
| 248 } | |
| 249 | |
| 250 private: | |
| 251 template <typename T, | |
| 252 bool is_array = IsSpecializationOf<Array, T>::value || | |
| 253 IsSpecializationOf<WTFArray, T>::value, | |
| 254 bool is_string = std::is_same<T, String>::value || | |
| 255 std::is_same<T, WTF::String>::value> | |
| 256 struct SerializeCaller { | |
| 257 static void Run(T input, | |
| 258 Buffer* buf, | |
| 259 DataElement* output, | |
| 260 const ArrayValidateParams* validate_params, | |
| 261 SerializationContext* context) { | |
| 262 DCHECK(!validate_params) | |
| 263 << "Struct type should not have array validate params"; | |
| 264 | |
| 265 Serialize_(std::move(input), buf, output, context); | |
| 266 } | |
| 267 }; | |
| 268 | |
| 269 template <typename T> | |
| 270 struct SerializeCaller<T, true, false> { | |
| 271 static void Run(T input, | |
| 272 Buffer* buf, | |
| 273 DataElement* output, | |
| 274 const ArrayValidateParams* validate_params, | |
| 275 SerializationContext* context) { | |
| 276 SerializeArray_(std::move(input), buf, output, validate_params, context); | |
| 277 } | |
| 278 }; | |
| 279 | |
| 280 template <typename T, typename U> | |
| 281 struct SerializeCaller<Map<T, U>, false, false> { | |
| 282 static void Run(Map<T, U> input, | |
| 283 Buffer* buf, | |
| 284 DataElement* output, | |
| 285 const ArrayValidateParams* validate_params, | |
| 286 SerializationContext* context) { | |
| 287 SerializeMap_(std::move(input), buf, output, validate_params, context); | |
| 288 } | |
| 289 }; | |
| 290 | |
| 291 template <typename T> | |
| 292 struct SerializeCaller<T, false, true> { | |
| 293 static void Run(const T& input, | |
| 294 Buffer* buf, | |
| 295 DataElement* output, | |
| 296 const ArrayValidateParams* validate_params, | |
| 297 SerializationContext* context) { | |
| 298 DCHECK(validate_params && !validate_params->element_validate_params && | |
| 299 !validate_params->element_is_nullable && | |
| 300 validate_params->expected_num_elements == 0) | |
| 301 << "String type has unexpected array validate params"; | |
| 302 | |
| 303 Serialize_(input, buf, output, context); | |
| 304 } | |
| 305 }; | |
| 306 }; | |
| 307 | |
| 308 // Handles serialization and deserialization of arrays of unions. | |
| 309 template <typename MojomType, typename UserType> | |
| 310 struct ArraySerializer<MojomType, UserType, ArraySerializerType::UNION> { | |
| 311 using Data = typename MojomType::Data_; | |
| 312 using DataElement = typename Data::Element; | |
| 313 using Element = typename MojomType::Element; | |
| 314 using Traits = ArrayTraits<UserType>; | |
| 315 using UserElement = typename Traits::Element; | |
| 316 | |
| 317 static_assert(std::is_same<Element, UserElement>::value, | |
| 318 "Incorrect array serializer"); | |
| 319 | |
| 320 static size_t GetSerializedSize(const UserType& input, | |
| 321 SerializationContext* context) { | |
| 322 size_t element_count = Traits::GetSize(input); | |
| 323 size_t size = sizeof(Data); | |
| 324 for (size_t i = 0; i < element_count; ++i) { | |
| 325 // Call GetSerializedSize_ with |inlined| set to false, so that it will | |
| 326 // account for both the data in the union and the space in the array used | |
| 327 // to hold the union. | |
| 328 size += GetSerializedSize_(Traits::GetAt(input, i), false, context); | |
| 329 } | |
| 330 return size; | |
| 331 } | |
| 332 | |
| 333 static void SerializeElements(UserType input, | |
| 334 Buffer* buf, | |
| 335 Data* output, | |
| 336 const ArrayValidateParams* validate_params, | |
| 337 SerializationContext* context) { | |
| 338 size_t size = Traits::GetSize(input); | |
| 339 for (size_t i = 0; i < size; ++i) { | |
| 340 DataElement* result = output->storage() + i; | |
| 341 SerializeUnion_(std::move(Traits::GetAt(input, i)), buf, &result, true, | |
| 342 context); | |
| 343 MOJO_INTERNAL_DLOG_SERIALIZATION_WARNING( | |
| 344 !validate_params->element_is_nullable && output->at(i).is_null(), | |
| 345 VALIDATION_ERROR_UNEXPECTED_NULL_POINTER, | |
| 346 MakeMessageWithArrayIndex("null in array expecting valid unions", | |
| 347 size, i)); | |
| 348 } | |
| 349 } | |
| 350 | |
| 351 static bool DeserializeElements(Data* input, | |
| 352 UserType* output, | |
| 353 SerializationContext* context) { | |
| 354 bool success = true; | |
| 355 Traits::Resize(*output, input->size()); | |
| 356 for (size_t i = 0; i < input->size(); ++i) { | |
| 357 // Note that we rely on complete deserialization taking place in order to | |
| 358 // transfer ownership of all encoded handles. Therefore we don't | |
| 359 // short-circuit on failure here. | |
| 360 if (!Deserialize_(&input->at(i), &Traits::GetAt(*output, i), context)) | |
| 361 success = false; | |
| 362 } | |
| 363 return success; | |
| 364 } | |
| 365 }; | |
| 366 | |
| 367 // Another layer of abstraction to switch between standard mojom type | |
| 368 // serializers and native-only serializers. | |
| 369 template <typename MojomType, | |
| 370 typename UserType, | |
| 371 bool use_native = | |
| 372 ShouldUseNativeSerializer<typename MojomType::Element>::value> | |
| 373 struct ArraySerializationStrategy; | |
| 374 | |
| 375 // Serialization strategy for standard mojom types. This branches further | |
| 376 // by choosing an ArraySerializer specialization from above. | |
| 377 template <typename MojomType, typename UserType> | |
| 378 struct ArraySerializationStrategy<MojomType, UserType, false> { | |
| 379 using Serializer = ArraySerializer<MojomType, UserType>; | |
| 380 using Traits = ArrayTraits<UserType>; | |
| 381 using Data = typename MojomType::Data_; | |
| 382 | |
| 383 static size_t GetSerializedSize(const UserType& input, | |
| 384 SerializationContext* context) { | |
| 385 DCHECK(!Traits::IsNull(input)); | |
| 386 return Serializer::GetSerializedSize(input, context); | |
| 387 } | |
| 388 | |
| 389 static void Serialize(UserType input, | |
| 390 Buffer* buf, | |
| 391 Data** output, | |
| 392 const ArrayValidateParams* validate_params, | |
| 393 SerializationContext* context) { | |
| 394 DCHECK(!Traits::IsNull(input)); | |
| 395 Data* result = Data::New(Traits::GetSize(input), buf); | |
| 396 if (result) { | |
| 397 Serializer::SerializeElements(std::move(input), buf, result, | |
| 398 validate_params, context); | |
| 399 } | |
| 400 *output = result; | |
| 401 } | |
| 402 | |
| 403 static bool Deserialize(Data* input, | |
| 404 UserType* output, | |
| 405 SerializationContext* context) { | |
| 406 DCHECK(input); | |
| 407 return Serializer::DeserializeElements(input, output, context); | |
| 408 } | |
| 409 }; | |
| 410 | |
| 411 // Serialization for arrays of native-only types, which are opaquely serialized | |
| 412 // as arrays of uint8_t arrays. | |
| 413 template <typename MojomType, typename UserType> | |
| 414 struct ArraySerializationStrategy<MojomType, UserType, true> { | |
| 415 using Traits = ArrayTraits<UserType>; | |
| 416 using Data = typename MojomType::Data_; | |
| 417 using Element = typename MojomType::Element; | |
| 418 | |
| 419 static_assert( | |
| 420 std::is_same<Data, Array_Data<NativeStruct_Data*>>::value, | |
| 421 "Mismatched types for serializing array of native-only structs."); | |
| 422 | |
| 423 static size_t GetSerializedSize(const UserType& input, | |
| 424 SerializationContext* context) { | |
| 425 DCHECK(!Traits::IsNull(input)); | |
| 426 | |
| 427 size_t element_count = Traits::GetSize(input); | |
| 428 DCHECK_LE(element_count, std::numeric_limits<uint32_t>::max()); | |
| 429 size_t size = ArrayDataTraits<NativeStruct_Data*>::GetStorageSize( | |
| 430 static_cast<uint32_t>(element_count)); | |
| 431 for (size_t i = 0; i < element_count; ++i) { | |
| 432 size_t element_size = | |
| 433 PrepareToSerialize<NativeStructPtr>(Traits::GetAt(input, i), context); | |
| 434 DCHECK_LT(element_size, std::numeric_limits<uint32_t>::max()); | |
| 435 size += static_cast<uint32_t>(element_size); | |
| 436 } | |
| 437 return size; | |
| 438 } | |
| 439 | |
| 440 static void Serialize(UserType input, | |
| 441 Buffer* buf, | |
| 442 Data** output, | |
| 443 const ArrayValidateParams* validate_params, | |
| 444 SerializationContext* context) { | |
| 445 DCHECK(!Traits::IsNull(input)); | |
| 446 DCHECK(validate_params); | |
| 447 // TODO(rockot): We may want to support nullable (i.e. std::unique_ptr<T>) | |
| 448 // elements here. | |
| 449 DCHECK(!validate_params->element_is_nullable); | |
| 450 size_t element_count = Traits::GetSize(input); | |
| 451 Data* result = Data::New(element_count, buf); | |
| 452 for (size_t i = 0; i < element_count; ++i) | |
| 453 internal::Serialize<NativeStructPtr>(Traits::GetAt(input, i), buf, | |
| 454 &result->at(i), context); | |
| 455 *output = result; | |
| 456 } | |
| 457 | |
| 458 static bool Deserialize(Data* input, | |
| 459 UserType* output, | |
| 460 SerializationContext* context) { | |
| 461 DCHECK(input); | |
| 462 | |
| 463 Traits::Resize(*output, input->size()); | |
| 464 bool success = true; | |
| 465 for (size_t i = 0; i < input->size(); ++i) { | |
| 466 // We don't short-circuit on failure since we can't know what the native | |
| 467 // type's ParamTraits' expectations are. | |
| 468 if (!internal::Deserialize<NativeStructPtr>( | |
| 469 input->at(i), &Traits::GetAt(*output, i), context)) | |
| 470 success = false; | |
| 471 } | |
| 472 return success; | |
| 473 } | |
| 474 }; | |
| 475 | |
| 476 template <typename MojomType, typename UserType> | |
| 477 struct ArraySerializationImpl { | |
| 478 using Traits = ArrayTraits<UserType>; | |
| 479 using Strategy = ArraySerializationStrategy<MojomType, UserType>; | |
| 480 | |
| 481 static size_t GetSerializedSize(const UserType& input, | |
| 482 SerializationContext* context) { | |
| 483 if (Traits::IsNull(input)) | |
| 484 return 0; | |
| 485 return Strategy::GetSerializedSize(input, context); | |
| 486 } | |
| 487 | |
| 488 static void Serialize(UserType input, | |
| 489 internal::Buffer* buf, | |
| 490 typename MojomType::Data_** output, | |
| 491 const internal::ArrayValidateParams* validate_params, | |
| 492 SerializationContext* context) { | |
| 493 if (!Traits::IsNull(input)) { | |
| 494 MOJO_INTERNAL_DLOG_SERIALIZATION_WARNING( | |
| 495 validate_params->expected_num_elements != 0 && | |
| 496 Traits::GetSize(input) != validate_params->expected_num_elements, | |
| 497 internal::VALIDATION_ERROR_UNEXPECTED_ARRAY_HEADER, | |
| 498 internal::MakeMessageWithExpectedArraySize( | |
| 499 "fixed-size array has wrong number of elements", | |
| 500 Traits::GetSize(input), validate_params->expected_num_elements)); | |
| 501 Strategy::Serialize(std::move(input), buf, output, validate_params, | |
| 502 context); | |
| 503 } else { | |
| 504 *output = nullptr; | |
| 505 } | |
| 506 } | |
| 507 | |
| 508 static bool Deserialize(typename MojomType::Data_* input, | |
| 509 UserType* output, | |
| 510 internal::SerializationContext* context) { | |
| 511 if (input) | |
| 512 return Strategy::Deserialize(input, output, context); | |
| 513 Traits::SetToNull(*output); | |
| 514 return true; | |
| 515 } | |
| 516 }; | |
| 517 | |
| 518 } // namespace internal | |
| 519 | |
| 520 } // namespace mojo | |
| 521 | |
| 522 #endif // MOJO_PUBLIC_CPP_BINDINGS_LIB_ARRAY_SERIALIZATION_TRAITS_H_ | |
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Chromium Code Reviews
Issue 1953493002:
Mojo C++ bindings: custom type mapping for array - part 2 (Closed)
Base URL: https://chromium.googlesource.com/chromium/src.git@21_simplify