Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 1 | // Copyright 2014 the V8 project 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 V8_UTIL_H_ |
| 6 | #define V8_UTIL_H_ |
| 7 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 8 | #include "v8.h" // NOLINT(build/include) |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 9 | #include <map> |
| 10 | #include <vector> |
| 11 | |
| 12 | /** |
| 13 | * Support for Persistent containers. |
| 14 | * |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 15 | * C++11 embedders can use STL containers with Global values, |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 16 | * but pre-C++11 does not support the required move semantic and hence |
| 17 | * may want these container classes. |
| 18 | */ |
| 19 | namespace v8 { |
| 20 | |
| 21 | typedef uintptr_t PersistentContainerValue; |
| 22 | static const uintptr_t kPersistentContainerNotFound = 0; |
| 23 | enum PersistentContainerCallbackType { |
| 24 | kNotWeak, |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 25 | // These correspond to v8::WeakCallbackType |
| 26 | kWeakWithParameter, |
| 27 | kWeakWithInternalFields, |
| 28 | kWeak = kWeakWithParameter // For backwards compatibility. Deprecate. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 29 | }; |
| 30 | |
| 31 | |
| 32 | /** |
| 33 | * A default trait implemenation for PersistentValueMap which uses std::map |
| 34 | * as a backing map. |
| 35 | * |
| 36 | * Users will have to implement their own weak callbacks & dispose traits. |
| 37 | */ |
| 38 | template<typename K, typename V> |
| 39 | class StdMapTraits { |
| 40 | public: |
| 41 | // STL map & related: |
| 42 | typedef std::map<K, PersistentContainerValue> Impl; |
| 43 | typedef typename Impl::iterator Iterator; |
| 44 | |
| 45 | static bool Empty(Impl* impl) { return impl->empty(); } |
| 46 | static size_t Size(Impl* impl) { return impl->size(); } |
| 47 | static void Swap(Impl& a, Impl& b) { std::swap(a, b); } // NOLINT |
| 48 | static Iterator Begin(Impl* impl) { return impl->begin(); } |
| 49 | static Iterator End(Impl* impl) { return impl->end(); } |
| 50 | static K Key(Iterator it) { return it->first; } |
| 51 | static PersistentContainerValue Value(Iterator it) { return it->second; } |
| 52 | static PersistentContainerValue Set(Impl* impl, K key, |
| 53 | PersistentContainerValue value) { |
| 54 | std::pair<Iterator, bool> res = impl->insert(std::make_pair(key, value)); |
| 55 | PersistentContainerValue old_value = kPersistentContainerNotFound; |
| 56 | if (!res.second) { |
| 57 | old_value = res.first->second; |
| 58 | res.first->second = value; |
| 59 | } |
| 60 | return old_value; |
| 61 | } |
| 62 | static PersistentContainerValue Get(Impl* impl, K key) { |
| 63 | Iterator it = impl->find(key); |
| 64 | if (it == impl->end()) return kPersistentContainerNotFound; |
| 65 | return it->second; |
| 66 | } |
| 67 | static PersistentContainerValue Remove(Impl* impl, K key) { |
| 68 | Iterator it = impl->find(key); |
| 69 | if (it == impl->end()) return kPersistentContainerNotFound; |
| 70 | PersistentContainerValue value = it->second; |
| 71 | impl->erase(it); |
| 72 | return value; |
| 73 | } |
| 74 | }; |
| 75 | |
| 76 | |
| 77 | /** |
| 78 | * A default trait implementation for PersistentValueMap, which inherits |
| 79 | * a std:map backing map from StdMapTraits and holds non-weak persistent |
| 80 | * objects and has no special Dispose handling. |
| 81 | * |
| 82 | * You should not derive from this class, since MapType depends on the |
| 83 | * surrounding class, and hence a subclass cannot simply inherit the methods. |
| 84 | */ |
| 85 | template<typename K, typename V> |
| 86 | class DefaultPersistentValueMapTraits : public StdMapTraits<K, V> { |
| 87 | public: |
| 88 | // Weak callback & friends: |
| 89 | static const PersistentContainerCallbackType kCallbackType = kNotWeak; |
| 90 | typedef PersistentValueMap<K, V, DefaultPersistentValueMapTraits<K, V> > |
| 91 | MapType; |
| 92 | typedef void WeakCallbackDataType; |
| 93 | |
| 94 | static WeakCallbackDataType* WeakCallbackParameter( |
| 95 | MapType* map, const K& key, Local<V> value) { |
| 96 | return NULL; |
| 97 | } |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 98 | static MapType* MapFromWeakCallbackInfo( |
| 99 | const WeakCallbackInfo<WeakCallbackDataType>& data) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 100 | return NULL; |
| 101 | } |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 102 | static K KeyFromWeakCallbackInfo( |
| 103 | const WeakCallbackInfo<WeakCallbackDataType>& data) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 104 | return K(); |
| 105 | } |
| 106 | static void DisposeCallbackData(WeakCallbackDataType* data) { } |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 107 | static void Dispose(Isolate* isolate, Global<V> value, K key) {} |
| 108 | }; |
| 109 | |
| 110 | |
| 111 | template <typename K, typename V> |
| 112 | class DefaultGlobalMapTraits : public StdMapTraits<K, V> { |
| 113 | private: |
| 114 | template <typename T> |
| 115 | struct RemovePointer; |
| 116 | |
| 117 | public: |
| 118 | // Weak callback & friends: |
| 119 | static const PersistentContainerCallbackType kCallbackType = kNotWeak; |
| 120 | typedef GlobalValueMap<K, V, DefaultGlobalMapTraits<K, V> > MapType; |
| 121 | typedef void WeakCallbackDataType; |
| 122 | |
| 123 | static WeakCallbackDataType* WeakCallbackParameter(MapType* map, const K& key, |
| 124 | Local<V> value) { |
| 125 | return nullptr; |
| 126 | } |
| 127 | static MapType* MapFromWeakCallbackInfo( |
| 128 | const WeakCallbackInfo<WeakCallbackDataType>& data) { |
| 129 | return nullptr; |
| 130 | } |
| 131 | static K KeyFromWeakCallbackInfo( |
| 132 | const WeakCallbackInfo<WeakCallbackDataType>& data) { |
| 133 | return K(); |
| 134 | } |
| 135 | static void DisposeCallbackData(WeakCallbackDataType* data) {} |
| 136 | static void OnWeakCallback( |
| 137 | const WeakCallbackInfo<WeakCallbackDataType>& data) {} |
| 138 | static void Dispose(Isolate* isolate, Global<V> value, K key) {} |
| 139 | // This is a second pass callback, so SetSecondPassCallback cannot be called. |
| 140 | static void DisposeWeak(const WeakCallbackInfo<WeakCallbackDataType>& data) {} |
| 141 | |
| 142 | private: |
| 143 | template <typename T> |
| 144 | struct RemovePointer<T*> { |
| 145 | typedef T Type; |
| 146 | }; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 147 | }; |
| 148 | |
| 149 | |
| 150 | /** |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 151 | * A map wrapper that allows using Global as a mapped value. |
| 152 | * C++11 embedders don't need this class, as they can use Global |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 153 | * directly in std containers. |
| 154 | * |
| 155 | * The map relies on a backing map, whose type and accessors are described |
| 156 | * by the Traits class. The backing map will handle values of type |
| 157 | * PersistentContainerValue, with all conversion into and out of V8 |
| 158 | * handles being transparently handled by this class. |
| 159 | */ |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 160 | template <typename K, typename V, typename Traits> |
| 161 | class PersistentValueMapBase { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 162 | public: |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 163 | Isolate* GetIsolate() { return isolate_; } |
| 164 | |
| 165 | /** |
| 166 | * Return size of the map. |
| 167 | */ |
| 168 | size_t Size() { return Traits::Size(&impl_); } |
| 169 | |
| 170 | /** |
| 171 | * Return whether the map holds weak persistents. |
| 172 | */ |
| 173 | bool IsWeak() { return Traits::kCallbackType != kNotWeak; } |
| 174 | |
| 175 | /** |
| 176 | * Get value stored in map. |
| 177 | */ |
| 178 | Local<V> Get(const K& key) { |
| 179 | return Local<V>::New(isolate_, FromVal(Traits::Get(&impl_, key))); |
| 180 | } |
| 181 | |
| 182 | /** |
| 183 | * Check whether a value is contained in the map. |
| 184 | */ |
| 185 | bool Contains(const K& key) { |
| 186 | return Traits::Get(&impl_, key) != kPersistentContainerNotFound; |
| 187 | } |
| 188 | |
| 189 | /** |
| 190 | * Get value stored in map and set it in returnValue. |
| 191 | * Return true if a value was found. |
| 192 | */ |
| 193 | bool SetReturnValue(const K& key, |
| 194 | ReturnValue<Value> returnValue) { |
| 195 | return SetReturnValueFromVal(&returnValue, Traits::Get(&impl_, key)); |
| 196 | } |
| 197 | |
| 198 | /** |
| 199 | * Call Isolate::SetReference with the given parent and the map value. |
| 200 | */ |
| 201 | void SetReference(const K& key, |
| 202 | const Persistent<Object>& parent) { |
| 203 | GetIsolate()->SetReference( |
| 204 | reinterpret_cast<internal::Object**>(parent.val_), |
| 205 | reinterpret_cast<internal::Object**>(FromVal(Traits::Get(&impl_, key)))); |
| 206 | } |
| 207 | |
| 208 | /** |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 209 | * Call V8::RegisterExternallyReferencedObject with the map value for given |
| 210 | * key. |
| 211 | */ |
| 212 | void RegisterExternallyReferencedObject(K& key) { |
| 213 | DCHECK(Contains(key)); |
| 214 | V8::RegisterExternallyReferencedObject( |
| 215 | reinterpret_cast<internal::Object**>(FromVal(Traits::Get(&impl_, key))), |
| 216 | reinterpret_cast<internal::Isolate*>(GetIsolate())); |
| 217 | } |
| 218 | |
| 219 | /** |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 220 | * Return value for key and remove it from the map. |
| 221 | */ |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 222 | Global<V> Remove(const K& key) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 223 | return Release(Traits::Remove(&impl_, key)).Pass(); |
| 224 | } |
| 225 | |
| 226 | /** |
| 227 | * Traverses the map repeatedly, |
| 228 | * in case side effects of disposal cause insertions. |
| 229 | **/ |
| 230 | void Clear() { |
| 231 | typedef typename Traits::Iterator It; |
| 232 | HandleScope handle_scope(isolate_); |
| 233 | // TODO(dcarney): figure out if this swap and loop is necessary. |
| 234 | while (!Traits::Empty(&impl_)) { |
| 235 | typename Traits::Impl impl; |
| 236 | Traits::Swap(impl_, impl); |
| 237 | for (It i = Traits::Begin(&impl); i != Traits::End(&impl); ++i) { |
| 238 | Traits::Dispose(isolate_, Release(Traits::Value(i)).Pass(), |
| 239 | Traits::Key(i)); |
| 240 | } |
| 241 | } |
| 242 | } |
| 243 | |
| 244 | /** |
| 245 | * Helper class for GetReference/SetWithReference. Do not use outside |
| 246 | * that context. |
| 247 | */ |
| 248 | class PersistentValueReference { |
| 249 | public: |
| 250 | PersistentValueReference() : value_(kPersistentContainerNotFound) { } |
| 251 | PersistentValueReference(const PersistentValueReference& other) |
| 252 | : value_(other.value_) { } |
| 253 | |
| 254 | Local<V> NewLocal(Isolate* isolate) const { |
| 255 | return Local<V>::New(isolate, FromVal(value_)); |
| 256 | } |
| 257 | bool IsEmpty() const { |
| 258 | return value_ == kPersistentContainerNotFound; |
| 259 | } |
| 260 | template<typename T> |
| 261 | bool SetReturnValue(ReturnValue<T> returnValue) { |
| 262 | return SetReturnValueFromVal(&returnValue, value_); |
| 263 | } |
| 264 | void Reset() { |
| 265 | value_ = kPersistentContainerNotFound; |
| 266 | } |
| 267 | void operator=(const PersistentValueReference& other) { |
| 268 | value_ = other.value_; |
| 269 | } |
| 270 | |
| 271 | private: |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 272 | friend class PersistentValueMapBase; |
| 273 | friend class PersistentValueMap<K, V, Traits>; |
| 274 | friend class GlobalValueMap<K, V, Traits>; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 275 | |
| 276 | explicit PersistentValueReference(PersistentContainerValue value) |
| 277 | : value_(value) { } |
| 278 | |
| 279 | void operator=(PersistentContainerValue value) { |
| 280 | value_ = value; |
| 281 | } |
| 282 | |
| 283 | PersistentContainerValue value_; |
| 284 | }; |
| 285 | |
| 286 | /** |
| 287 | * Get a reference to a map value. This enables fast, repeated access |
| 288 | * to a value stored in the map while the map remains unchanged. |
| 289 | * |
| 290 | * Careful: This is potentially unsafe, so please use with care. |
| 291 | * The value will become invalid if the value for this key changes |
| 292 | * in the underlying map, as a result of Set or Remove for the same |
| 293 | * key; as a result of the weak callback for the same key; or as a |
| 294 | * result of calling Clear() or destruction of the map. |
| 295 | */ |
| 296 | PersistentValueReference GetReference(const K& key) { |
| 297 | return PersistentValueReference(Traits::Get(&impl_, key)); |
| 298 | } |
| 299 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 300 | protected: |
| 301 | explicit PersistentValueMapBase(Isolate* isolate) : isolate_(isolate) {} |
| 302 | |
| 303 | ~PersistentValueMapBase() { Clear(); } |
| 304 | |
| 305 | Isolate* isolate() { return isolate_; } |
| 306 | typename Traits::Impl* impl() { return &impl_; } |
| 307 | |
| 308 | static V* FromVal(PersistentContainerValue v) { |
| 309 | return reinterpret_cast<V*>(v); |
| 310 | } |
| 311 | |
| 312 | static PersistentContainerValue ClearAndLeak(Global<V>* persistent) { |
| 313 | V* v = persistent->val_; |
| 314 | persistent->val_ = 0; |
| 315 | return reinterpret_cast<PersistentContainerValue>(v); |
| 316 | } |
| 317 | |
| 318 | static PersistentContainerValue Leak(Global<V>* persistent) { |
| 319 | return reinterpret_cast<PersistentContainerValue>(persistent->val_); |
| 320 | } |
| 321 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 322 | /** |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 323 | * Return a container value as Global and make sure the weak |
| 324 | * callback is properly disposed of. All remove functionality should go |
| 325 | * through this. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 326 | */ |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 327 | static Global<V> Release(PersistentContainerValue v) { |
| 328 | Global<V> p; |
| 329 | p.val_ = FromVal(v); |
| 330 | if (Traits::kCallbackType != kNotWeak && p.IsWeak()) { |
| 331 | Traits::DisposeCallbackData( |
| 332 | p.template ClearWeak<typename Traits::WeakCallbackDataType>()); |
| 333 | } |
| 334 | return p.Pass(); |
| 335 | } |
| 336 | |
| 337 | void RemoveWeak(const K& key) { |
| 338 | Global<V> p; |
| 339 | p.val_ = FromVal(Traits::Remove(&impl_, key)); |
| 340 | p.Reset(); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 341 | } |
| 342 | |
| 343 | private: |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 344 | PersistentValueMapBase(PersistentValueMapBase&); |
| 345 | void operator=(PersistentValueMapBase&); |
| 346 | |
| 347 | static bool SetReturnValueFromVal(ReturnValue<Value>* returnValue, |
| 348 | PersistentContainerValue value) { |
| 349 | bool hasValue = value != kPersistentContainerNotFound; |
| 350 | if (hasValue) { |
| 351 | returnValue->SetInternal( |
| 352 | *reinterpret_cast<internal::Object**>(FromVal(value))); |
| 353 | } |
| 354 | return hasValue; |
| 355 | } |
| 356 | |
| 357 | Isolate* isolate_; |
| 358 | typename Traits::Impl impl_; |
| 359 | }; |
| 360 | |
| 361 | |
| 362 | template <typename K, typename V, typename Traits> |
| 363 | class PersistentValueMap : public PersistentValueMapBase<K, V, Traits> { |
| 364 | public: |
| 365 | explicit PersistentValueMap(Isolate* isolate) |
| 366 | : PersistentValueMapBase<K, V, Traits>(isolate) {} |
| 367 | |
| 368 | typedef |
| 369 | typename PersistentValueMapBase<K, V, Traits>::PersistentValueReference |
| 370 | PersistentValueReference; |
| 371 | |
| 372 | /** |
| 373 | * Put value into map. Depending on Traits::kIsWeak, the value will be held |
| 374 | * by the map strongly or weakly. |
| 375 | * Returns old value as Global. |
| 376 | */ |
| 377 | Global<V> Set(const K& key, Local<V> value) { |
| 378 | Global<V> persistent(this->isolate(), value); |
| 379 | return SetUnique(key, &persistent); |
| 380 | } |
| 381 | |
| 382 | /** |
| 383 | * Put value into map, like Set(const K&, Local<V>). |
| 384 | */ |
| 385 | Global<V> Set(const K& key, Global<V> value) { |
| 386 | return SetUnique(key, &value); |
| 387 | } |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 388 | |
| 389 | /** |
| 390 | * Put the value into the map, and set the 'weak' callback when demanded |
| 391 | * by the Traits class. |
| 392 | */ |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 393 | Global<V> SetUnique(const K& key, Global<V>* persistent) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 394 | if (Traits::kCallbackType != kNotWeak) { |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 395 | Local<V> value(Local<V>::New(this->isolate(), *persistent)); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 396 | persistent->template SetWeak<typename Traits::WeakCallbackDataType>( |
| 397 | Traits::WeakCallbackParameter(this, key, value), WeakCallback); |
| 398 | } |
| 399 | PersistentContainerValue old_value = |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 400 | Traits::Set(this->impl(), key, this->ClearAndLeak(persistent)); |
| 401 | return this->Release(old_value).Pass(); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 402 | } |
| 403 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 404 | /** |
| 405 | * Put a value into the map and update the reference. |
| 406 | * Restrictions of GetReference apply here as well. |
| 407 | */ |
| 408 | Global<V> Set(const K& key, Global<V> value, |
| 409 | PersistentValueReference* reference) { |
| 410 | *reference = this->Leak(&value); |
| 411 | return SetUnique(key, &value); |
| 412 | } |
| 413 | |
| 414 | private: |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 415 | static void WeakCallback( |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 416 | const WeakCallbackInfo<typename Traits::WeakCallbackDataType>& data) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 417 | if (Traits::kCallbackType != kNotWeak) { |
| 418 | PersistentValueMap<K, V, Traits>* persistentValueMap = |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 419 | Traits::MapFromWeakCallbackInfo(data); |
| 420 | K key = Traits::KeyFromWeakCallbackInfo(data); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 421 | Traits::Dispose(data.GetIsolate(), |
| 422 | persistentValueMap->Remove(key).Pass(), key); |
| 423 | Traits::DisposeCallbackData(data.GetParameter()); |
| 424 | } |
| 425 | } |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 426 | }; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 427 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 428 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 429 | template <typename K, typename V, typename Traits> |
| 430 | class GlobalValueMap : public PersistentValueMapBase<K, V, Traits> { |
| 431 | public: |
| 432 | explicit GlobalValueMap(Isolate* isolate) |
| 433 | : PersistentValueMapBase<K, V, Traits>(isolate) {} |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 434 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 435 | typedef |
| 436 | typename PersistentValueMapBase<K, V, Traits>::PersistentValueReference |
| 437 | PersistentValueReference; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 438 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 439 | /** |
| 440 | * Put value into map. Depending on Traits::kIsWeak, the value will be held |
| 441 | * by the map strongly or weakly. |
| 442 | * Returns old value as Global. |
| 443 | */ |
| 444 | Global<V> Set(const K& key, Local<V> value) { |
| 445 | Global<V> persistent(this->isolate(), value); |
| 446 | return SetUnique(key, &persistent); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 447 | } |
| 448 | |
| 449 | /** |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 450 | * Put value into map, like Set(const K&, Local<V>). |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 451 | */ |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 452 | Global<V> Set(const K& key, Global<V> value) { |
| 453 | return SetUnique(key, &value); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 454 | } |
| 455 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 456 | /** |
| 457 | * Put the value into the map, and set the 'weak' callback when demanded |
| 458 | * by the Traits class. |
| 459 | */ |
| 460 | Global<V> SetUnique(const K& key, Global<V>* persistent) { |
| 461 | if (Traits::kCallbackType != kNotWeak) { |
| 462 | WeakCallbackType callback_type = |
| 463 | Traits::kCallbackType == kWeakWithInternalFields |
| 464 | ? WeakCallbackType::kInternalFields |
| 465 | : WeakCallbackType::kParameter; |
| 466 | Local<V> value(Local<V>::New(this->isolate(), *persistent)); |
| 467 | persistent->template SetWeak<typename Traits::WeakCallbackDataType>( |
| 468 | Traits::WeakCallbackParameter(this, key, value), OnWeakCallback, |
| 469 | callback_type); |
| 470 | } |
| 471 | PersistentContainerValue old_value = |
| 472 | Traits::Set(this->impl(), key, this->ClearAndLeak(persistent)); |
| 473 | return this->Release(old_value).Pass(); |
| 474 | } |
| 475 | |
| 476 | /** |
| 477 | * Put a value into the map and update the reference. |
| 478 | * Restrictions of GetReference apply here as well. |
| 479 | */ |
| 480 | Global<V> Set(const K& key, Global<V> value, |
| 481 | PersistentValueReference* reference) { |
| 482 | *reference = this->Leak(&value); |
| 483 | return SetUnique(key, &value); |
| 484 | } |
| 485 | |
| 486 | private: |
| 487 | static void OnWeakCallback( |
| 488 | const WeakCallbackInfo<typename Traits::WeakCallbackDataType>& data) { |
| 489 | if (Traits::kCallbackType != kNotWeak) { |
| 490 | auto map = Traits::MapFromWeakCallbackInfo(data); |
| 491 | K key = Traits::KeyFromWeakCallbackInfo(data); |
| 492 | map->RemoveWeak(key); |
| 493 | Traits::OnWeakCallback(data); |
| 494 | data.SetSecondPassCallback(SecondWeakCallback); |
| 495 | } |
| 496 | } |
| 497 | |
| 498 | static void SecondWeakCallback( |
| 499 | const WeakCallbackInfo<typename Traits::WeakCallbackDataType>& data) { |
| 500 | Traits::DisposeWeak(data); |
| 501 | } |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 502 | }; |
| 503 | |
| 504 | |
| 505 | /** |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 506 | * A map that uses Global as value and std::map as the backing |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 507 | * implementation. Persistents are held non-weak. |
| 508 | * |
| 509 | * C++11 embedders don't need this class, as they can use |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 510 | * Global directly in std containers. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 511 | */ |
| 512 | template<typename K, typename V, |
| 513 | typename Traits = DefaultPersistentValueMapTraits<K, V> > |
| 514 | class StdPersistentValueMap : public PersistentValueMap<K, V, Traits> { |
| 515 | public: |
| 516 | explicit StdPersistentValueMap(Isolate* isolate) |
| 517 | : PersistentValueMap<K, V, Traits>(isolate) {} |
| 518 | }; |
| 519 | |
| 520 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 521 | /** |
| 522 | * A map that uses Global as value and std::map as the backing |
| 523 | * implementation. Globals are held non-weak. |
| 524 | * |
| 525 | * C++11 embedders don't need this class, as they can use |
| 526 | * Global directly in std containers. |
| 527 | */ |
| 528 | template <typename K, typename V, |
| 529 | typename Traits = DefaultGlobalMapTraits<K, V> > |
| 530 | class StdGlobalValueMap : public GlobalValueMap<K, V, Traits> { |
| 531 | public: |
| 532 | explicit StdGlobalValueMap(Isolate* isolate) |
| 533 | : GlobalValueMap<K, V, Traits>(isolate) {} |
| 534 | }; |
| 535 | |
| 536 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 537 | class DefaultPersistentValueVectorTraits { |
| 538 | public: |
| 539 | typedef std::vector<PersistentContainerValue> Impl; |
| 540 | |
| 541 | static void Append(Impl* impl, PersistentContainerValue value) { |
| 542 | impl->push_back(value); |
| 543 | } |
| 544 | static bool IsEmpty(const Impl* impl) { |
| 545 | return impl->empty(); |
| 546 | } |
| 547 | static size_t Size(const Impl* impl) { |
| 548 | return impl->size(); |
| 549 | } |
| 550 | static PersistentContainerValue Get(const Impl* impl, size_t i) { |
| 551 | return (i < impl->size()) ? impl->at(i) : kPersistentContainerNotFound; |
| 552 | } |
| 553 | static void ReserveCapacity(Impl* impl, size_t capacity) { |
| 554 | impl->reserve(capacity); |
| 555 | } |
| 556 | static void Clear(Impl* impl) { |
| 557 | impl->clear(); |
| 558 | } |
| 559 | }; |
| 560 | |
| 561 | |
| 562 | /** |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 563 | * A vector wrapper that safely stores Global values. |
| 564 | * C++11 embedders don't need this class, as they can use Global |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 565 | * directly in std containers. |
| 566 | * |
| 567 | * This class relies on a backing vector implementation, whose type and methods |
| 568 | * are described by the Traits class. The backing map will handle values of type |
| 569 | * PersistentContainerValue, with all conversion into and out of V8 |
| 570 | * handles being transparently handled by this class. |
| 571 | */ |
| 572 | template<typename V, typename Traits = DefaultPersistentValueVectorTraits> |
| 573 | class PersistentValueVector { |
| 574 | public: |
| 575 | explicit PersistentValueVector(Isolate* isolate) : isolate_(isolate) { } |
| 576 | |
| 577 | ~PersistentValueVector() { |
| 578 | Clear(); |
| 579 | } |
| 580 | |
| 581 | /** |
| 582 | * Append a value to the vector. |
| 583 | */ |
| 584 | void Append(Local<V> value) { |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 585 | Global<V> persistent(isolate_, value); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 586 | Traits::Append(&impl_, ClearAndLeak(&persistent)); |
| 587 | } |
| 588 | |
| 589 | /** |
| 590 | * Append a persistent's value to the vector. |
| 591 | */ |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 592 | void Append(Global<V> persistent) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 593 | Traits::Append(&impl_, ClearAndLeak(&persistent)); |
| 594 | } |
| 595 | |
| 596 | /** |
| 597 | * Are there any values in the vector? |
| 598 | */ |
| 599 | bool IsEmpty() const { |
| 600 | return Traits::IsEmpty(&impl_); |
| 601 | } |
| 602 | |
| 603 | /** |
| 604 | * How many elements are in the vector? |
| 605 | */ |
| 606 | size_t Size() const { |
| 607 | return Traits::Size(&impl_); |
| 608 | } |
| 609 | |
| 610 | /** |
| 611 | * Retrieve the i-th value in the vector. |
| 612 | */ |
| 613 | Local<V> Get(size_t index) const { |
| 614 | return Local<V>::New(isolate_, FromVal(Traits::Get(&impl_, index))); |
| 615 | } |
| 616 | |
| 617 | /** |
| 618 | * Remove all elements from the vector. |
| 619 | */ |
| 620 | void Clear() { |
| 621 | size_t length = Traits::Size(&impl_); |
| 622 | for (size_t i = 0; i < length; i++) { |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 623 | Global<V> p; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 624 | p.val_ = FromVal(Traits::Get(&impl_, i)); |
| 625 | } |
| 626 | Traits::Clear(&impl_); |
| 627 | } |
| 628 | |
| 629 | /** |
| 630 | * Reserve capacity in the vector. |
| 631 | * (Efficiency gains depend on the backing implementation.) |
| 632 | */ |
| 633 | void ReserveCapacity(size_t capacity) { |
| 634 | Traits::ReserveCapacity(&impl_, capacity); |
| 635 | } |
| 636 | |
| 637 | private: |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 638 | static PersistentContainerValue ClearAndLeak(Global<V>* persistent) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 639 | V* v = persistent->val_; |
| 640 | persistent->val_ = 0; |
| 641 | return reinterpret_cast<PersistentContainerValue>(v); |
| 642 | } |
| 643 | |
| 644 | static V* FromVal(PersistentContainerValue v) { |
| 645 | return reinterpret_cast<V*>(v); |
| 646 | } |
| 647 | |
| 648 | Isolate* isolate_; |
| 649 | typename Traits::Impl impl_; |
| 650 | }; |
| 651 | |
| 652 | } // namespace v8 |
| 653 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 654 | #endif // V8_UTIL_H |