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 "content/renderer/pepper/v8_var_converter.h" 11 #include "ppapi/c/pp_var.h" 12 #include "ppapi/shared_impl/scoped_pp_var.h" 13 #include "v8/include/v8.h" 14 15 namespace content { 16 17 class PepperPluginInstanceImpl; 18 19 // Base class for scripting TryCatch helpers. 20 class CONTENT_EXPORT PepperTryCatch { 21 public: 22 // PepperTryCatch objects should only be used as stack variables. This object 23 // takes a reference on the given PepperPluginInstanceImpl. 24 PepperTryCatch(PepperPluginInstanceImpl* instance, 25 V8VarConverter::AllowObjectVars convert_objects); 26 virtual ~PepperTryCatch(); 27 28 virtual void SetException(const char* message) = 0; 29 virtual bool HasException() = 0; 30 // Gets the context to execute scripts in. 31 virtual v8::Handle<v8::Context> GetContext() = 0; 32 33 // Convenience functions for doing conversions to/from V8 values and sets an 34 // exception if there is an error in the conversion. 35 v8::Handle<v8::Value> ToV8(PP_Var var); 36 ppapi::ScopedPPVar FromV8(v8::Handle<v8::Value> v8_value); 37 38 protected: 39 // Make sure that |instance_| is alive for the lifetime of PepperTryCatch. 40 // PepperTryCatch is used mostly in Pepper scripting code, where it can be 41 // possible to enter JavaScript synchronously which can cause the plugin to 42 // be deleted. 43 // 44 // Note that PepperTryCatch objects should only ever be on the stack, so this 45 // shouldn't keep the instance around for too long. 46 scoped_refptr<PepperPluginInstanceImpl> instance_; 47 48 // Whether To/FromV8 should convert object vars. If set to 49 // kDisallowObjectVars, an exception should be set if they are encountered 50 // during conversion. 51 V8VarConverter::AllowObjectVars convert_objects_; 52 }; 53 54 // Catches var exceptions and emits a v8 exception. 55 class PepperTryCatchV8 : public PepperTryCatch { 56 public: 57 PepperTryCatchV8(PepperPluginInstanceImpl* instance, 58 V8VarConverter::AllowObjectVars convert_objects, 59 v8::Isolate* isolate); 60 virtual ~PepperTryCatchV8(); 61 62 bool ThrowException(); 63 void ThrowException(const char* message); 64 PP_Var* exception() { return &exception_; } 65 66 // PepperTryCatch 67 virtual void SetException(const char* message) OVERRIDE; 68 virtual bool HasException() OVERRIDE; 69 virtual v8::Handle<v8::Context> GetContext() OVERRIDE; 70 71 private: 72 PP_Var exception_; 73 74 DISALLOW_COPY_AND_ASSIGN(PepperTryCatchV8); 75 }; 76 77 // Catches v8 exceptions and emits a var exception. 78 class PepperTryCatchVar : public PepperTryCatch { 79 public: 80 // The PP_Var exception will be placed in |exception|. The user of this class 81 // is responsible for managing the lifetime of the exception. It is valid to 82 // pass NULL for |exception| in which case no exception will be set. 83 PepperTryCatchVar(PepperPluginInstanceImpl* instance, 84 PP_Var* exception); 85 virtual ~PepperTryCatchVar(); 86 87 // PepperTryCatch 88 virtual void SetException(const char* message) OVERRIDE; 89 virtual bool HasException() OVERRIDE; 90 virtual v8::Handle<v8::Context> GetContext() OVERRIDE; 91 92 private: 93 // Code which uses PepperTryCatchVar doesn't typically have a HandleScope, 94 // make one for them. Note that this class is always allocated on the stack. 95 v8::HandleScope handle_scope_; 96 97 v8::Handle<v8::Context> context_; 98 99 v8::TryCatch try_catch_; 100 101 PP_Var* exception_; 102 bool exception_is_set_; 103 104 DISALLOW_COPY_AND_ASSIGN(PepperTryCatchVar); 105 }; 106 107 } // namespace content 108 109 #endif // CONTENT_RENDERER_PEPPER_PEPPER_TRY_CATCH_H_ 110