Add PepperTryCatch and V8ObjectVar classes

content/renderer/pepper/pepper_try_catch.h

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_RENDERER_PEPPER_PEPPER_TRY_CATCH_H_
+#define CONTENT_RENDERER_PEPPER_PEPPER_TRY_CATCH_H_
+
+#include "base/basictypes.h"
+#include "ppapi/c/pp_var.h"
+#include "ppapi/shared_impl/scoped_pp_var.h"
+#include "v8/include/v8.h"
+
+namespace content {
+
+class PepperPluginInstanceImpl;
+
+// Base class for scripting TryCatch helpers.
+class PepperTryCatch {
+ public:
+  PepperTryCatch(PepperPluginInstanceImpl* instance,
+                 bool convert_objects);
+  virtual ~PepperTryCatch();
+
+  virtual void SetException(const char* message) = 0;
+  // Gets the plugin context. Virtual so it can be overriden for testing.
+  virtual v8::Handle<v8::Context> GetContext();
+
+  // Convenience functions for doing conversions to/from V8 values and sets an
+  // exception if there is an error in the conversion.
+  v8::Handle<v8::Value> ToV8(PP_Var var);
+  ppapi::ScopedPPVar FromV8(v8::Handle<v8::Value> v8_value);
+
+ protected:
+  PepperPluginInstanceImpl* instance_;
+
+  // Whether To/FromV8 should convert object vars. If set to false, an exception
+  // should be set if they are encountered during conversion.
+  bool convert_objects_;
+};
+
+// Catches var exceptions and emits a v8 exception.
+class PepperTryCatchV8 : public PepperTryCatch {
+ public:
+  PepperTryCatchV8(PepperPluginInstanceImpl* instance,
+                   bool convert_objects,
+                   v8::Isolate* isolate);
+  virtual ~PepperTryCatchV8();
+
+  bool HasException();
+  bool ThrowException();
+  void ThrowException(const char* message);
+  PP_Var* exception() { return &exception_; }
+
+  // PepperTryCatch
+  virtual void SetException(const char* message) OVERRIDE;
+
+ private:
+  PP_Var exception_;
+
+  DISALLOW_COPY_AND_ASSIGN(PepperTryCatchV8);
+};
+
+// Catches v8 exceptions and emits a var exception.
+class PepperTryCatchVar : public PepperTryCatch {
+ public:
+  // The PP_Var exception will be placed in |exception|. The user of this class
+  // is responsible for managing the lifetime of the exception. It is valid to
+  //  pass NULL for |exception| in which case no exception will be set.
+  PepperTryCatchVar(PepperPluginInstanceImpl* instance,
+                    bool convert_objects,
+                    PP_Var* exception);
+  virtual ~PepperTryCatchVar();
+
+  bool HasException();
+
+  // PepperTryCatch
+  virtual void SetException(const char* message) OVERRIDE;
+
+ private:
+  // Code which uses PepperTryCatchVar doesn't typically have a HandleScope,
+  // make one for them. Note that this class is always allocated on the stack.
+  v8::HandleScope handle_scope_;
+
+  v8::TryCatch try_catch_;
+
+  PP_Var* exception_;
+  bool exception_is_set_;
+
+  DISALLOW_COPY_AND_ASSIGN(PepperTryCatchVar);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_RENDERER_PEPPER_PEPPER_TRY_CATCH_H_