gin/public/context_holder.h

   1 // Copyright 2013 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 GIN_PUBLIC_CONTEXT_HOLDER_H_
   6 #define GIN_PUBLIC_CONTEXT_HOLDER_H_
   7
   8 #include <list>
   9
  10 #include "base/basictypes.h"
  11 #include "base/memory/scoped_ptr.h"
  12 #include "gin/gin_export.h"
  13 #include "v8/include/v8.h"
  14
  15 namespace gin {
  16
  17 // Gin embedder that store embedder data in v8::Contexts must do so in a
  18 // single field with the index kPerContextDataStartIndex + GinEmbedder-enum.
  19 // The field at kDebugIdIndex is treated specially by V8 and is reserved for
  20 // a V8 debugger implementation (not used by gin).
  21 enum ContextEmbedderDataFields {
  22   kDebugIdIndex = 0,
  23   kPerContextDataStartIndex,
  24 };
  25
  26 class PerContextData;
  27
  28 // ContextHolder is a generic class for holding a v8::Context. Rather than
  29 // using ContextHolder directly, most code should use a subclass of
  30 // ContextHolder, such as Runner.
  31 class GIN_EXPORT ContextHolder {
  32  public:
  33   explicit ContextHolder(v8::Isolate* isolate);
  34   ~ContextHolder();
  35
  36   v8::Isolate* isolate() const { return isolate_; }
  37
  38   v8::Handle<v8::Context> context() const {
  39     return v8::Local<v8::Context>::New(isolate_, context_);
  40   }
  41
  42   void SetContext(v8::Handle<v8::Context> context);
  43
  44  private:
  45   v8::Isolate* isolate_;
  46   v8::UniquePersistent<v8::Context> context_;
  47   scoped_ptr<PerContextData> data_;
  48
  49   DISALLOW_COPY_AND_ASSIGN(ContextHolder);
  50 };
  51
  52 }  // namespace gin
  53
  54 #endif  // GIN_PUBLIC_CONTEXT_HOLDER_H_