content/renderer/pepper/v8_var_converter.h

   1 // Copyright (c) 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 CONTENT_RENDERER_PEPPER_V8_VAR_CONVERTER_H_
   6 #define CONTENT_RENDERER_PEPPER_V8_VAR_CONVERTER_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/callback.h"
  10 #include "base/compiler_specific.h"
  11 #include "base/message_loop/message_loop_proxy.h"
  12 #include "ppapi/c/pp_instance.h"
  13 #include "ppapi/c/pp_var.h"
  14 #include "ppapi/shared_impl/scoped_pp_var.h"
  15 #include "v8/include/v8.h"
  16 #include "content/common/content_export.h"
  17
  18 namespace content {
  19
  20 class ResourceConverter;
  21
  22 class CONTENT_EXPORT V8VarConverter {
  23  public:
  24   // Whether or not to allow converting object vars. If they are not allowed
  25   // and they are passed in, conversion will fail.
  26   enum AllowObjectVars {
  27     kDisallowObjectVars,
  28     kAllowObjectVars
  29   };
  30   V8VarConverter(PP_Instance instance, AllowObjectVars object_vars_allowed);
  31
  32   // Constructor for testing.
  33   V8VarConverter(PP_Instance instance,
  34                  scoped_ptr<ResourceConverter> resource_converter);
  35   ~V8VarConverter();
  36
  37   // Converts the given PP_Var to a v8::Value. True is returned upon success.
  38   bool ToV8Value(const PP_Var& var,
  39                  v8::Handle<v8::Context> context,
  40                  v8::Handle<v8::Value>* result);
  41
  42   struct VarResult {
  43    public:
  44     VarResult() : completed_synchronously(false), success(false) {}
  45
  46     // True if the conversion completed synchronously and the callback will not
  47     // be called.
  48     bool completed_synchronously;
  49
  50     // True if the conversion was successful. Only valid if
  51     // |completed_synchronously| is true.
  52     bool success;
  53
  54     // The result if the conversion was successful. Only valid if
  55     // |completed_synchronously| and |success| are true.
  56     ppapi::ScopedPPVar var;
  57   };
  58
  59   // Converts the given v8::Value to a PP_Var. Every PP_Var in the reference
  60   // graph in the result will have a refcount equal to the number of references
  61   // to it in the graph. The root of the result will have one additional
  62   // reference. The callback is run when conversion is complete with the
  63   // resulting var and a bool indicating success or failure. Conversion may be
  64   // asynchronous because converting some resources may result in communication
  65   // across IPC. |context| is guaranteed to only be used synchronously. If
  66   // the conversion can occur synchronously, |callback| will not be run,
  67   // otherwise it will be run.
  68   VarResult FromV8Value(
  69       v8::Handle<v8::Value> val,
  70       v8::Handle<v8::Context> context,
  71       const base::Callback<void(const ppapi::ScopedPPVar&, bool)>& callback);
  72   bool FromV8ValueSync(v8::Handle<v8::Value> val,
  73                        v8::Handle<v8::Context> context,
  74                        ppapi::ScopedPPVar* result_var);
  75  private:
  76   // Returns true on success, false on failure.
  77   bool FromV8ValueInternal(v8::Handle<v8::Value> val,
  78                            v8::Handle<v8::Context> context,
  79                            ppapi::ScopedPPVar* result_var);
  80
  81   PP_Instance instance_;
  82
  83   // Whether or not to support conversion to PP_VARTYPE_OBJECT.
  84   AllowObjectVars object_vars_allowed_;
  85
  86   // The converter to use for converting V8 vars to resources.
  87   scoped_ptr<ResourceConverter> resource_converter_;
  88
  89   DISALLOW_COPY_AND_ASSIGN(V8VarConverter);
  90 };
  91
  92 }  // namespace content
  93
  94 #endif  // CONTENT_RENDERER_PEPPER_V8_VAR_CONVERTER_H_