Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 1 | // Copyright 2013 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_V8_PLATFORM_H_ |
| 6 | #define V8_V8_PLATFORM_H_ |
| 7 | |
| 8 | namespace v8 { |
| 9 | |
| 10 | class Isolate; |
| 11 | |
| 12 | /** |
| 13 | * A Task represents a unit of work. |
| 14 | */ |
| 15 | class Task { |
| 16 | public: |
| 17 | virtual ~Task() {} |
| 18 | |
| 19 | virtual void Run() = 0; |
| 20 | }; |
| 21 | |
| 22 | /** |
| 23 | * V8 Platform abstraction layer. |
| 24 | * |
| 25 | * The embedder has to provide an implementation of this interface before |
| 26 | * initializing the rest of V8. |
| 27 | */ |
| 28 | class Platform { |
| 29 | public: |
| 30 | /** |
| 31 | * This enum is used to indicate whether a task is potentially long running, |
| 32 | * or causes a long wait. The embedder might want to use this hint to decide |
| 33 | * whether to execute the task on a dedicated thread. |
| 34 | */ |
| 35 | enum ExpectedRuntime { |
| 36 | kShortRunningTask, |
| 37 | kLongRunningTask |
| 38 | }; |
| 39 | |
| 40 | virtual ~Platform() {} |
| 41 | |
| 42 | /** |
| 43 | * Schedules a task to be invoked on a background thread. |expected_runtime| |
| 44 | * indicates that the task will run a long time. The Platform implementation |
| 45 | * takes ownership of |task|. There is no guarantee about order of execution |
| 46 | * of tasks wrt order of scheduling, nor is there a guarantee about the |
| 47 | * thread the task will be run on. |
| 48 | */ |
| 49 | virtual void CallOnBackgroundThread(Task* task, |
| 50 | ExpectedRuntime expected_runtime) = 0; |
| 51 | |
| 52 | /** |
| 53 | * Schedules a task to be invoked on a foreground thread wrt a specific |
| 54 | * |isolate|. Tasks posted for the same isolate should be execute in order of |
| 55 | * scheduling. The definition of "foreground" is opaque to V8. |
| 56 | */ |
| 57 | virtual void CallOnForegroundThread(Isolate* isolate, Task* task) = 0; |
| 58 | }; |
| 59 | |
| 60 | } // namespace v8 |
| 61 | |
| 62 | #endif // V8_V8_PLATFORM_H_ |