michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-*/
michael@0: /* vim: set ts=2 sw=2 et tw=79: */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
michael@0:  * You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: /**
michael@0:  * A header for declaring various things that binding implementation headers
michael@0:  * might need.  The idea is to make binding implementation headers safe to
michael@0:  * include anywhere without running into include hell like we do with
michael@0:  * BindingUtils.h
michael@0:  */
michael@0: #ifndef mozilla_dom_BindingDeclarations_h__
michael@0: #define mozilla_dom_BindingDeclarations_h__
michael@0: 
michael@0: #include "nsStringGlue.h"
michael@0: #include "js/Value.h"
michael@0: #include "js/RootingAPI.h"
michael@0: #include "mozilla/Maybe.h"
michael@0: #include "nsCOMPtr.h"
michael@0: #include "nsTArray.h"
michael@0: #include "nsAutoPtr.h" // for nsRefPtr member variables
michael@0: #include "mozilla/dom/DOMString.h"
michael@0: #include "mozilla/dom/OwningNonNull.h"
michael@0: 
michael@0: class nsWrapperCache;
michael@0: 
michael@0: namespace mozilla {
michael@0: namespace dom {
michael@0: 
michael@0: // Struct that serves as a base class for all dictionaries.  Particularly useful
michael@0: // so we can use IsBaseOf to detect dictionary template arguments.
michael@0: struct DictionaryBase
michael@0: {
michael@0: protected:
michael@0:   bool ParseJSON(JSContext* aCx, const nsAString& aJSON,
michael@0:                  JS::MutableHandle<JS::Value> aVal);
michael@0: };
michael@0: 
michael@0: // Struct that serves as a base class for all typed arrays and array buffers and
michael@0: // array buffer views.  Particularly useful so we can use IsBaseOf to detect
michael@0: // typed array/buffer/view template arguments.
michael@0: struct AllTypedArraysBase {
michael@0: };
michael@0: 
michael@0: // Struct that serves as a base class for all owning unions.
michael@0: // Particularly useful so we can use IsBaseOf to detect owning union
michael@0: // template arguments.
michael@0: struct AllOwningUnionBase {
michael@0: };
michael@0: 
michael@0: 
michael@0: struct EnumEntry {
michael@0:   const char* value;
michael@0:   size_t length;
michael@0: };
michael@0: 
michael@0: class MOZ_STACK_CLASS GlobalObject
michael@0: {
michael@0: public:
michael@0:   GlobalObject(JSContext* aCx, JSObject* aObject);
michael@0: 
michael@0:   JSObject* Get() const
michael@0:   {
michael@0:     return mGlobalJSObject;
michael@0:   }
michael@0: 
michael@0:   nsISupports* GetAsSupports() const;
michael@0: 
michael@0:   // The context that this returns is not guaranteed to be in the compartment of
michael@0:   // the object returned from Get(), in fact it's generally in the caller's
michael@0:   // compartment.
michael@0:   JSContext* GetContext() const
michael@0:   {
michael@0:     return mCx;
michael@0:   }
michael@0: 
michael@0:   bool Failed() const
michael@0:   {
michael@0:     return !Get();
michael@0:   }
michael@0: 
michael@0: protected:
michael@0:   JS::Rooted<JSObject*> mGlobalJSObject;
michael@0:   JSContext* mCx;
michael@0:   mutable nsISupports* mGlobalObject;
michael@0:   mutable nsCOMPtr<nsISupports> mGlobalObjectRef;
michael@0: };
michael@0: 
michael@0: // Class for representing optional arguments.
michael@0: template<typename T, typename InternalType>
michael@0: class Optional_base
michael@0: {
michael@0: public:
michael@0:   Optional_base()
michael@0:   {}
michael@0: 
michael@0:   explicit Optional_base(const T& aValue)
michael@0:   {
michael@0:     mImpl.construct(aValue);
michael@0:   }
michael@0: 
michael@0:   template<typename T1, typename T2>
michael@0:   explicit Optional_base(const T1& aValue1, const T2& aValue2)
michael@0:   {
michael@0:     mImpl.construct(aValue1, aValue2);
michael@0:   }
michael@0: 
michael@0:   bool WasPassed() const
michael@0:   {
michael@0:     return !mImpl.empty();
michael@0:   }
michael@0: 
michael@0:   // Return InternalType here so we can work with it usefully.
michael@0:   InternalType& Construct()
michael@0:   {
michael@0:     mImpl.construct();
michael@0:     return mImpl.ref();
michael@0:   }
michael@0: 
michael@0:   template <class T1>
michael@0:   InternalType& Construct(const T1 &t1)
michael@0:   {
michael@0:     mImpl.construct(t1);
michael@0:     return mImpl.ref();
michael@0:   }
michael@0: 
michael@0:   template <class T1, class T2>
michael@0:   InternalType& Construct(const T1 &t1, const T2 &t2)
michael@0:   {
michael@0:     mImpl.construct(t1, t2);
michael@0:     return mImpl.ref();
michael@0:   }
michael@0: 
michael@0:   void Reset()
michael@0:   {
michael@0:     if (WasPassed()) {
michael@0:       mImpl.destroy();
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   const T& Value() const
michael@0:   {
michael@0:     return mImpl.ref();
michael@0:   }
michael@0: 
michael@0:   // Return InternalType here so we can work with it usefully.
michael@0:   InternalType& Value()
michael@0:   {
michael@0:     return mImpl.ref();
michael@0:   }
michael@0: 
michael@0:   // And an explicit way to get the InternalType even if we're const.
michael@0:   const InternalType& InternalValue() const
michael@0:   {
michael@0:     return mImpl.ref();
michael@0:   }
michael@0: 
michael@0:   // If we ever decide to add conversion operators for optional arrays
michael@0:   // like the ones Nullable has, we'll need to ensure that Maybe<> has
michael@0:   // the boolean before the actual data.
michael@0: 
michael@0: private:
michael@0:   // Forbid copy-construction and assignment
michael@0:   Optional_base(const Optional_base& other) MOZ_DELETE;
michael@0:   const Optional_base &operator=(const Optional_base &other) MOZ_DELETE;
michael@0: 
michael@0: protected:
michael@0:   Maybe<InternalType> mImpl;
michael@0: };
michael@0: 
michael@0: template<typename T>
michael@0: class Optional : public Optional_base<T, T>
michael@0: {
michael@0: public:
michael@0:   Optional() :
michael@0:     Optional_base<T, T>()
michael@0:   {}
michael@0: 
michael@0:   explicit Optional(const T& aValue) :
michael@0:     Optional_base<T, T>(aValue)
michael@0:   {}
michael@0: };
michael@0: 
michael@0: template<typename T>
michael@0: class Optional<JS::Handle<T> > :
michael@0:   public Optional_base<JS::Handle<T>, JS::Rooted<T> >
michael@0: {
michael@0: public:
michael@0:   Optional() :
michael@0:     Optional_base<JS::Handle<T>, JS::Rooted<T> >()
michael@0:   {}
michael@0: 
michael@0:   Optional(JSContext* cx) :
michael@0:     Optional_base<JS::Handle<T>, JS::Rooted<T> >()
michael@0:   {
michael@0:     this->Construct(cx);
michael@0:   }
michael@0: 
michael@0:   Optional(JSContext* cx, const T& aValue) :
michael@0:     Optional_base<JS::Handle<T>, JS::Rooted<T> >(cx, aValue)
michael@0:   {}
michael@0: 
michael@0:   // Override the const Value() to return the right thing so we're not
michael@0:   // returning references to temporaries.
michael@0:   JS::Handle<T> Value() const
michael@0:   {
michael@0:     return this->mImpl.ref();
michael@0:   }
michael@0: 
michael@0:   // And we have to override the non-const one too, since we're
michael@0:   // shadowing the one on the superclass.
michael@0:   JS::Rooted<T>& Value()
michael@0:   {
michael@0:     return this->mImpl.ref();
michael@0:   }
michael@0: };
michael@0: 
michael@0: // A specialization of Optional for JSObject* to make sure that when someone
michael@0: // calls Construct() on it we will pre-initialized the JSObject* to nullptr so
michael@0: // it can be traced safely.
michael@0: template<>
michael@0: class Optional<JSObject*> : public Optional_base<JSObject*, JSObject*>
michael@0: {
michael@0: public:
michael@0:   Optional() :
michael@0:     Optional_base<JSObject*, JSObject*>()
michael@0:   {}
michael@0: 
michael@0:   explicit Optional(JSObject* aValue) :
michael@0:     Optional_base<JSObject*, JSObject*>(aValue)
michael@0:   {}
michael@0: 
michael@0:   // Don't allow us to have an uninitialized JSObject*
michael@0:   JSObject*& Construct()
michael@0:   {
michael@0:     // The Android compiler sucks and thinks we're trying to construct
michael@0:     // a JSObject* from an int if we don't cast here.  :(
michael@0:     return Optional_base<JSObject*, JSObject*>::Construct(
michael@0:       static_cast<JSObject*>(nullptr));
michael@0:   }
michael@0: 
michael@0:   template <class T1>
michael@0:   JSObject*& Construct(const T1& t1)
michael@0:   {
michael@0:     return Optional_base<JSObject*, JSObject*>::Construct(t1);
michael@0:   }
michael@0: };
michael@0: 
michael@0: // A specialization of Optional for JS::Value to make sure no one ever uses it.
michael@0: template<>
michael@0: class Optional<JS::Value>
michael@0: {
michael@0: private:
michael@0:   Optional() MOZ_DELETE;
michael@0: 
michael@0:   explicit Optional(JS::Value aValue) MOZ_DELETE;
michael@0: };
michael@0: 
michael@0: // A specialization of Optional for NonNull that lets us get a T& from Value()
michael@0: template<typename U> class NonNull;
michael@0: template<typename T>
michael@0: class Optional<NonNull<T> > : public Optional_base<T, NonNull<T> >
michael@0: {
michael@0: public:
michael@0:   // We want our Value to actually return a non-const reference, even
michael@0:   // if we're const.  At least for things that are normally pointer
michael@0:   // types...
michael@0:   T& Value() const
michael@0:   {
michael@0:     return *this->mImpl.ref().get();
michael@0:   }
michael@0: 
michael@0:   // And we have to override the non-const one too, since we're
michael@0:   // shadowing the one on the superclass.
michael@0:   NonNull<T>& Value()
michael@0:   {
michael@0:     return this->mImpl.ref();
michael@0:   }
michael@0: };
michael@0: 
michael@0: // A specialization of Optional for OwningNonNull that lets us get a
michael@0: // T& from Value()
michael@0: template<typename T>
michael@0: class Optional<OwningNonNull<T> > : public Optional_base<T, OwningNonNull<T> >
michael@0: {
michael@0: public:
michael@0:   // We want our Value to actually return a non-const reference, even
michael@0:   // if we're const.  At least for things that are normally pointer
michael@0:   // types...
michael@0:   T& Value() const
michael@0:   {
michael@0:     return *this->mImpl.ref().get();
michael@0:   }
michael@0: 
michael@0:   // And we have to override the non-const one too, since we're
michael@0:   // shadowing the one on the superclass.
michael@0:   OwningNonNull<T>& Value()
michael@0:   {
michael@0:     return this->mImpl.ref();
michael@0:   }
michael@0: };
michael@0: 
michael@0: // Specialization for strings.
michael@0: // XXXbz we can't pull in FakeDependentString here, because it depends on
michael@0: // internal strings.  So we just have to forward-declare it and reimplement its
michael@0: // ToAStringPtr.
michael@0: 
michael@0: namespace binding_detail {
michael@0: struct FakeDependentString;
michael@0: } // namespace binding_detail
michael@0: 
michael@0: template<>
michael@0: class Optional<nsAString>
michael@0: {
michael@0: public:
michael@0:   Optional() : mPassed(false) {}
michael@0: 
michael@0:   bool WasPassed() const
michael@0:   {
michael@0:     return mPassed;
michael@0:   }
michael@0: 
michael@0:   void operator=(const nsAString* str)
michael@0:   {
michael@0:     MOZ_ASSERT(str);
michael@0:     mStr = str;
michael@0:     mPassed = true;
michael@0:   }
michael@0: 
michael@0:   // If this code ever goes away, remove the comment pointing to it in the
michael@0:   // FakeDependentString class in BindingUtils.h.
michael@0:   void operator=(const binding_detail::FakeDependentString* str)
michael@0:   {
michael@0:     MOZ_ASSERT(str);
michael@0:     mStr = reinterpret_cast<const nsDependentString*>(str);
michael@0:     mPassed = true;
michael@0:   }
michael@0: 
michael@0:   const nsAString& Value() const
michael@0:   {
michael@0:     MOZ_ASSERT(WasPassed());
michael@0:     return *mStr;
michael@0:   }
michael@0: 
michael@0: private:
michael@0:   // Forbid copy-construction and assignment
michael@0:   Optional(const Optional& other) MOZ_DELETE;
michael@0:   const Optional &operator=(const Optional &other) MOZ_DELETE;
michael@0: 
michael@0:   bool mPassed;
michael@0:   const nsAString* mStr;
michael@0: };
michael@0: 
michael@0: template<class T>
michael@0: class NonNull
michael@0: {
michael@0: public:
michael@0:   NonNull()
michael@0: #ifdef DEBUG
michael@0:     : inited(false)
michael@0: #endif
michael@0:   {}
michael@0: 
michael@0:   operator T&() {
michael@0:     MOZ_ASSERT(inited);
michael@0:     MOZ_ASSERT(ptr, "NonNull<T> was set to null");
michael@0:     return *ptr;
michael@0:   }
michael@0: 
michael@0:   operator const T&() const {
michael@0:     MOZ_ASSERT(inited);
michael@0:     MOZ_ASSERT(ptr, "NonNull<T> was set to null");
michael@0:     return *ptr;
michael@0:   }
michael@0: 
michael@0:   operator T*() {
michael@0:     MOZ_ASSERT(inited);
michael@0:     MOZ_ASSERT(ptr, "NonNull<T> was set to null");
michael@0:     return ptr;
michael@0:   }
michael@0: 
michael@0:   void operator=(T* t) {
michael@0:     ptr = t;
michael@0:     MOZ_ASSERT(ptr);
michael@0: #ifdef DEBUG
michael@0:     inited = true;
michael@0: #endif
michael@0:   }
michael@0: 
michael@0:   template<typename U>
michael@0:   void operator=(U* t) {
michael@0:     ptr = t->ToAStringPtr();
michael@0:     MOZ_ASSERT(ptr);
michael@0: #ifdef DEBUG
michael@0:     inited = true;
michael@0: #endif
michael@0:   }
michael@0: 
michael@0:   T** Slot() {
michael@0: #ifdef DEBUG
michael@0:     inited = true;
michael@0: #endif
michael@0:     return &ptr;
michael@0:   }
michael@0: 
michael@0:   T* Ptr() {
michael@0:     MOZ_ASSERT(inited);
michael@0:     MOZ_ASSERT(ptr, "NonNull<T> was set to null");
michael@0:     return ptr;
michael@0:   }
michael@0: 
michael@0:   // Make us work with smart-ptr helpers that expect a get()
michael@0:   T* get() const {
michael@0:     MOZ_ASSERT(inited);
michael@0:     MOZ_ASSERT(ptr);
michael@0:     return ptr;
michael@0:   }
michael@0: 
michael@0: protected:
michael@0:   T* ptr;
michael@0: #ifdef DEBUG
michael@0:   bool inited;
michael@0: #endif
michael@0: };
michael@0: 
michael@0: // Class for representing sequences in arguments.  We use a non-auto array
michael@0: // because that allows us to use sequences of sequences and the like.  This
michael@0: // needs to be fallible because web content controls the length of the array,
michael@0: // and can easily try to create very large lengths.
michael@0: template<typename T>
michael@0: class Sequence : public FallibleTArray<T>
michael@0: {
michael@0: public:
michael@0:   Sequence() : FallibleTArray<T>()
michael@0:   {}
michael@0: };
michael@0: 
michael@0: inline nsWrapperCache*
michael@0: GetWrapperCache(nsWrapperCache* cache)
michael@0: {
michael@0:   return cache;
michael@0: }
michael@0: 
michael@0: inline nsWrapperCache*
michael@0: GetWrapperCache(void* p)
michael@0: {
michael@0:   return nullptr;
michael@0: }
michael@0: 
michael@0: // Helper template for smart pointers to resolve ambiguity between
michael@0: // GetWrappeCache(void*) and GetWrapperCache(const ParentObject&).
michael@0: template <template <typename> class SmartPtr, typename T>
michael@0: inline nsWrapperCache*
michael@0: GetWrapperCache(const SmartPtr<T>& aObject)
michael@0: {
michael@0:   return GetWrapperCache(aObject.get());
michael@0: }
michael@0: 
michael@0: struct ParentObject {
michael@0:   template<class T>
michael@0:   ParentObject(T* aObject) :
michael@0:     mObject(aObject),
michael@0:     mWrapperCache(GetWrapperCache(aObject)),
michael@0:     mUseXBLScope(false)
michael@0:   {}
michael@0: 
michael@0:   template<class T, template<typename> class SmartPtr>
michael@0:   ParentObject(const SmartPtr<T>& aObject) :
michael@0:     mObject(aObject.get()),
michael@0:     mWrapperCache(GetWrapperCache(aObject.get())),
michael@0:     mUseXBLScope(false)
michael@0:   {}
michael@0: 
michael@0:   ParentObject(nsISupports* aObject, nsWrapperCache* aCache) :
michael@0:     mObject(aObject),
michael@0:     mWrapperCache(aCache),
michael@0:     mUseXBLScope(false)
michael@0:   {}
michael@0: 
michael@0:   nsISupports* const mObject;
michael@0:   nsWrapperCache* const mWrapperCache;
michael@0:   bool mUseXBLScope;
michael@0: };
michael@0: 
michael@0: } // namespace dom
michael@0: } // namespace mozilla
michael@0: 
michael@0: #endif // mozilla_dom_BindingDeclarations_h__