content/renderer/pepper/pepper_try_catch.h

   1 // Copyright 2014 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_PEPPER_TRY_CATCH_H_
   6 #define CONTENT_RENDERER_PEPPER_PEPPER_TRY_CATCH_H_
   7
   8 #include "base/basictypes.h"
   9 #include "content/common/content_export.h"
  10 #include "ppapi/c/pp_var.h"
  11 #include "ppapi/shared_impl/scoped_pp_var.h"
  12 #include "v8/include/v8.h"
  13
  14 namespace content {
  15
  16 class PepperPluginInstanceImpl;
  17
  18 // Base class for scripting TryCatch helpers.
  19 class CONTENT_EXPORT PepperTryCatch {
  20  public:
  21   PepperTryCatch(PepperPluginInstanceImpl* instance,
  22                  bool convert_objects);
  23   virtual ~PepperTryCatch();
  24
  25   virtual void SetException(const char* message) = 0;
  26   // Gets the plugin context. Virtual so it can be overriden for testing.
  27   virtual v8::Handle<v8::Context> GetContext();
  28
  29   // Convenience functions for doing conversions to/from V8 values and sets an
  30   // exception if there is an error in the conversion.
  31   v8::Handle<v8::Value> ToV8(PP_Var var);
  32   ppapi::ScopedPPVar FromV8(v8::Handle<v8::Value> v8_value);
  33
  34  protected:
  35   PepperPluginInstanceImpl* instance_;
  36
  37   // Whether To/FromV8 should convert object vars. If set to false, an exception
  38   // should be set if they are encountered during conversion.
  39   bool convert_objects_;
  40 };
  41
  42 // Catches var exceptions and emits a v8 exception.
  43 class PepperTryCatchV8 : public PepperTryCatch {
  44  public:
  45   PepperTryCatchV8(PepperPluginInstanceImpl* instance,
  46                    bool convert_objects,
  47                    v8::Isolate* isolate);
  48   virtual ~PepperTryCatchV8();
  49
  50   bool HasException();
  51   bool ThrowException();
  52   void ThrowException(const char* message);
  53   PP_Var* exception() { return &exception_; }
  54
  55   // PepperTryCatch
  56   virtual void SetException(const char* message) OVERRIDE;
  57
  58  private:
  59   PP_Var exception_;
  60
  61   DISALLOW_COPY_AND_ASSIGN(PepperTryCatchV8);
  62 };
  63
  64 // Catches v8 exceptions and emits a var exception.
  65 class PepperTryCatchVar : public PepperTryCatch {
  66  public:
  67   // The PP_Var exception will be placed in |exception|. The user of this class
  68   // is responsible for managing the lifetime of the exception. It is valid to
  69   //  pass NULL for |exception| in which case no exception will be set.
  70   PepperTryCatchVar(PepperPluginInstanceImpl* instance,
  71                     bool convert_objects,
  72                     PP_Var* exception);
  73   virtual ~PepperTryCatchVar();
  74
  75   bool HasException();
  76
  77   // PepperTryCatch
  78   virtual void SetException(const char* message) OVERRIDE;
  79
  80  private:
  81   // Code which uses PepperTryCatchVar doesn't typically have a HandleScope,
  82   // make one for them. Note that this class is always allocated on the stack.
  83   v8::HandleScope handle_scope_;
  84
  85   v8::TryCatch try_catch_;
  86
  87   PP_Var* exception_;
  88   bool exception_is_set_;
  89
  90   DISALLOW_COPY_AND_ASSIGN(PepperTryCatchVar);
  91 };
  92
  93 }  // namespace content
  94
  95 #endif  // CONTENT_RENDERER_PEPPER_PEPPER_TRY_CATCH_H_