| // Copyright 2014 Google Inc. All Rights Reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #ifndef COBALT_SCRIPT_JAVASCRIPT_ENGINE_H_ |
| #define COBALT_SCRIPT_JAVASCRIPT_ENGINE_H_ |
| |
| #include <string> |
| |
| #include "base/callback.h" |
| #include "base/memory/ref_counted.h" |
| #include "base/memory/scoped_ptr.h" |
| #include "cobalt/base/source_location.h" |
| |
| namespace cobalt { |
| namespace script { |
| |
| class GlobalEnvironment; |
| |
| // https://webplatform.github.io/docs/apis/timing/properties/memory/ |
| struct HeapStatistics { |
| size_t total_heap_size; |
| size_t used_heap_size; |
| }; |
| |
| class JavaScriptEngine { |
| public: |
| struct Options { |
| Options() : disable_jit(false), gc_threshold_bytes(1024*1024) {} |
| |
| // Default false. When set to true then the JavaScript engine should |
| // disable the just-in-time compiler. |
| bool disable_jit; |
| |
| // Determines the size of garbage collection threshold. After this many |
| // bytes have been allocated, the garbage collector will run. |
| // Default is 1MB (see default constructor). |
| size_t gc_threshold_bytes; |
| }; |
| |
| typedef base::Callback<void(const base::SourceLocation& location, |
| const std::string& error_message)> ErrorHandler; |
| |
| // Initialize a JavaScript engine. The JavaScript engine should only be |
| // accessed from the thread that called CreateEngine. |
| // This function is defined per-implementation. |
| static scoped_ptr<JavaScriptEngine> CreateEngine( |
| const Options& options = Options()); |
| |
| // Create a new JavaScript global object proxy. |
| virtual scoped_refptr<GlobalEnvironment> CreateGlobalEnvironment() = 0; |
| |
| // Kick off the engine's garbage collection synchronously. |
| virtual void CollectGarbage() = 0; |
| |
| // Indicate to the JavaScript heap that extra bytes have been allocated by |
| // some Javascript object. The engine will take advantage of this |
| // information to the best of its ability. |
| virtual void AdjustAmountOfExternalAllocatedMemory(int64_t bytes) = 0; |
| |
| // Installs an ErrorHandler for listening to JavaScript errors. |
| // Returns true if the error handler could be installed. False otherwise. |
| virtual bool RegisterErrorHandler(ErrorHandler handler) = 0; |
| |
| // Adjusts the memory threshold to force garbage collection. |
| virtual void SetGcThreshold(int64_t bytes) = 0; |
| |
| // Get the current |HeapStatistics| measurements for this engine. Note that |
| // engines will implement this to the best of their ability, but will likely |
| // be unable to provide perfectly accurate values. |
| virtual HeapStatistics GetHeapStatistics() = 0; |
| |
| protected: |
| virtual ~JavaScriptEngine() {} |
| friend class scoped_ptr<JavaScriptEngine>; |
| }; |
| |
| } // namespace script |
| } // namespace cobalt |
| |
| #endif // COBALT_SCRIPT_JAVASCRIPT_ENGINE_H_ |