dom/ipc/ClonedErrorHolder.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim:set ts=2 sw=2 sts=2 et cindent: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_dom_ClonedErrorHolder_h
   8 #define mozilla_dom_ClonedErrorHolder_h
   9
  10 #include "nsISupportsImpl.h"
  11 #include "js/ColumnNumber.h"  // JS::ColumnNumberOneOrigin
  12 #include "js/ErrorReport.h"
  13 #include "js/TypeDecls.h"
  14 #include "mozilla/dom/BindingDeclarations.h"
  15 #include "mozilla/dom/StructuredCloneHolder.h"
  16 #include "mozilla/Attributes.h"
  17
  18 class nsIGlobalObject;
  19 class nsQueryActorChild;
  20
  21 namespace mozilla {
  22 class ErrorResult;
  23
  24 namespace dom {
  25
  26 class ClonedErrorHolder final {
  27   NS_INLINE_DECL_REFCOUNTING(ClonedErrorHolder)
  28
  29  public:
  30   static already_AddRefed<ClonedErrorHolder> Constructor(
  31       const GlobalObject& aGlobal, JS::Handle<JSObject*> aError,
  32       ErrorResult& aRv);
  33
  34   static already_AddRefed<ClonedErrorHolder> Create(
  35       JSContext* aCx, JS::Handle<JSObject*> aError, ErrorResult& aRv);
  36
  37   enum class Type : uint8_t {
  38     Uninitialized,
  39     JSError,
  40     Exception,
  41     DOMException,
  42     Max_,
  43   };
  44
  45   bool WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto,
  46                   JS::MutableHandle<JSObject*> aReflector);
  47
  48   bool WriteStructuredClone(JSContext* aCx, JSStructuredCloneWriter* aWriter,
  49                             StructuredCloneHolder* aHolder);
  50
  51   // Reads the structured clone data for the ClonedErrorHolder and returns the
  52   // wrapped object (either a JS Error or an Exception/DOMException object)
  53   // directly. Never returns an actual ClonedErrorHolder object.
  54   static JSObject* ReadStructuredClone(JSContext* aCx,
  55                                        JSStructuredCloneReader* aReader,
  56                                        StructuredCloneHolder* aHolder);
  57
  58  private:
  59   ClonedErrorHolder();
  60   ~ClonedErrorHolder() = default;
  61
  62   void Init(JSContext* aCx, JS::Handle<JSObject*> aError, ErrorResult& aRv);
  63
  64   bool Init(JSContext* aCx, JSStructuredCloneReader* aReader);
  65
  66   // Creates a new JS Error or Exception/DOMException object based on the
  67   // values stored in the holder. Returns false and sets an exception on aCx
  68   // if it fails.
  69   bool ToErrorValue(JSContext* aCx, JS::MutableHandle<JS::Value> aResult);
  70
  71   class Holder final : public StructuredCloneHolder {
  72    public:
  73     using StructuredCloneHolder::StructuredCloneHolder;
  74
  75     bool ReadStructuredCloneInternal(JSContext* aCx,
  76                                      JSStructuredCloneReader* aReader);
  77   };
  78
  79   // Only a subset of the following fields are used, depending on the mType of
  80   // the error stored:
  81   nsCString mName;        // Exception, DOMException
  82   nsCString mMessage;     // JSError, Exception, DOMException
  83   nsCString mFilename;    // JSError only
  84   nsCString mSourceLine;  // JSError only
  85
  86   uint32_t mLineNumber = 0;           // JSError only
  87   JS::ColumnNumberOneOrigin mColumn;  // JSError only
  88   uint32_t mTokenOffset = 0;          // JSError only
  89   uint32_t mErrorNumber = 0;          // JSError only
  90
  91   Type mType = Type::Uninitialized;
  92
  93   uint16_t mCode = 0;                 // DOMException only
  94   JSExnType mExnType = JSExnType(0);  // JSError only
  95   nsresult mResult = NS_OK;           // Exception, DOMException
  96
  97   // JSError, Exception, DOMException
  98   Holder mStack{Holder::CloningSupported, Holder::TransferringNotSupported,
  99                 Holder::StructuredCloneScope::DifferentProcess};
 100 };
 101
 102 }  // namespace dom
 103 }  // namespace mozilla
 104
 105 #endif  // !defined(mozilla_dom_ClonedErrorHolder_h)