dom/base/nsNameSpaceManager.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   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 nsNameSpaceManager_h___
   8 #define nsNameSpaceManager_h___
   9
  10 #include "nsTHashMap.h"
  11 #include "nsStringFwd.h"
  12 #include "nsTArray.h"
  13
  14 #include "mozilla/StaticPtr.h"
  15
  16 /**
  17  * The Name Space Manager tracks the association between a NameSpace
  18  * URI and the int32_t runtime id. Mappings between NameSpaces and
  19  * NameSpace prefixes are managed by nsINameSpaces.
  20  *
  21  * All NameSpace URIs are stored in a global table so that IDs are
  22  * consistent accross the app. NameSpace IDs are only consistent at runtime
  23  * ie: they are not guaranteed to be consistent accross app sessions.
  24  *
  25  * The nsNameSpaceManager needs to have a live reference for as long as
  26  * the NameSpace IDs are needed.
  27  *
  28  */
  29
  30 class nsNameSpaceManager final {
  31  public:
  32   NS_INLINE_DECL_REFCOUNTING(nsNameSpaceManager)
  33
  34   nsresult RegisterNameSpace(const nsAString& aURI, int32_t& aNameSpaceID);
  35   nsresult RegisterNameSpace(already_AddRefed<nsAtom> aURI,
  36                              int32_t& aNameSpaceID);
  37
  38   nsresult GetNameSpaceURI(int32_t aNameSpaceID, nsAString& aURI);
  39
  40   // Returns the atom for the namespace URI associated with the given ID. The
  41   // ID must be within range and not be kNameSpaceID_None (i.e. zero);
  42   //
  43   // NB: The requirement of mapping from the first entry to the empty atom is
  44   // necessary for Servo, though it can be removed if needed adding a branch in
  45   // GeckoElement::get_namespace().
  46   nsAtom* NameSpaceURIAtom(int32_t aNameSpaceID) {
  47     MOZ_ASSERT(aNameSpaceID > 0);
  48     MOZ_ASSERT((int64_t)aNameSpaceID < (int64_t)mURIArray.Length());
  49     return mURIArray.ElementAt(aNameSpaceID);
  50   }
  51
  52   int32_t GetNameSpaceID(const nsAString& aURI, bool aInChromeDoc);
  53   int32_t GetNameSpaceID(nsAtom* aURI, bool aInChromeDoc);
  54
  55   static const char* GetNameSpaceDisplayName(uint32_t aNameSpaceID);
  56
  57   bool HasElementCreator(int32_t aNameSpaceID);
  58
  59   static nsNameSpaceManager* GetInstance();
  60   bool mMathMLDisabled;
  61   bool mSVGDisabled;
  62
  63  private:
  64   static void PrefChanged(const char* aPref, void* aSelf);
  65   void PrefChanged(const char* aPref);
  66
  67   bool Init();
  68   nsresult AddNameSpace(already_AddRefed<nsAtom> aURI,
  69                         const int32_t aNameSpaceID);
  70   nsresult AddDisabledNameSpace(already_AddRefed<nsAtom> aURI,
  71                                 const int32_t aNameSpaceID);
  72   ~nsNameSpaceManager() = default;
  73
  74   nsTHashMap<RefPtr<nsAtom>, int32_t> mURIToIDTable;
  75   nsTHashMap<RefPtr<nsAtom>, int32_t> mDisabledURIToIDTable;
  76   nsTArray<RefPtr<nsAtom>> mURIArray;
  77
  78   static mozilla::StaticRefPtr<nsNameSpaceManager> sInstance;
  79 };
  80
  81 #endif  // nsNameSpaceManager_h___