[tor-commits] [tor-browser/tor-browser-31.5.0esr-4.5-1] Bug 13548: Create preference to disable MathML.

[gk at torproject.org]

commit 5b48b325cf54fe341c9c6c417ecfbb83cc5625be
Author: Kathy Brade <brade at pearlcrescent.com>
Date:   Thu Mar 5 18:50:59 2015 -0500

    Bug 13548: Create preference to disable MathML.
    
    If the mathml.disabled preference is true, treat <math> and other MathML
    elements as generic XML elements.
---
 content/base/public/nsNameSpaceManager.h |   11 +++++---
 content/base/src/nsNameSpaceManager.cpp  |   43 ++++++++++++++++++++++++++++--
 2 files changed, 49 insertions(+), 5 deletions(-)

diff --git a/content/base/public/nsNameSpaceManager.h b/content/base/public/nsNameSpaceManager.h
index 7f222a6..24b85f3 100644
--- a/content/base/public/nsNameSpaceManager.h
+++ b/content/base/public/nsNameSpaceManager.h
@@ -8,6 +8,7 @@
 
 #include "nsDataHashtable.h"
 #include "nsTArray.h"
+#include "nsIObserver.h"
 
 #include "mozilla/StaticPtr.h"
 
@@ -84,10 +85,13 @@ private:
  *
  */
 
-class nsNameSpaceManager
+class nsNameSpaceManager : public nsIObserver
 {
 public:
-  virtual ~nsNameSpaceManager() {}
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIOBSERVER
+
+  virtual ~nsNameSpaceManager();
 
   virtual nsresult RegisterNameSpace(const nsAString& aURI,
                                      int32_t& aNameSpaceID);
@@ -98,6 +102,7 @@ public:
   virtual bool HasElementCreator(int32_t aNameSpaceID);
 
   static nsNameSpaceManager* GetInstance();
+  bool mIsMathMLDisabled;
 private:
   bool Init();
   nsresult AddNameSpace(const nsAString& aURI, const int32_t aNameSpaceID);
@@ -105,7 +110,7 @@ private:
   nsDataHashtable<nsNameSpaceKey,int32_t> mURIToIDTable;
   nsTArray< nsAutoPtr<nsString> > mURIArray;
 
-  static mozilla::StaticAutoPtr<nsNameSpaceManager> sInstance;
+  static mozilla::StaticRefPtr<nsNameSpaceManager> sInstance;
 };
  
 #endif // nsNameSpaceManager_h___
diff --git a/content/base/src/nsNameSpaceManager.cpp b/content/base/src/nsNameSpaceManager.cpp
index 409e08c..d2a9722 100644
--- a/content/base/src/nsNameSpaceManager.cpp
+++ b/content/base/src/nsNameSpaceManager.cpp
@@ -20,6 +20,7 @@
 #include "mozilla/ClearOnShutdown.h"
 #include "mozilla/dom/XBLChildrenElement.h"
 #include "mozilla/dom/Element.h"
+#include "mozilla/Preferences.h"
 
 using namespace mozilla;
 using namespace mozilla::dom;
@@ -35,7 +36,14 @@ using namespace mozilla::dom;
 #define kXULNameSpaceURI "http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
 #define kSVGNameSpaceURI "http://www.w3.org/2000/svg"
 
-StaticAutoPtr<nsNameSpaceManager> nsNameSpaceManager::sInstance;
+static const char kMathMLDisabledPrefName[] = "mathml.disabled";
+
+static const char* kObservedPrefs[] = {
+  kMathMLDisabledPrefName,
+  nullptr
+};
+
+StaticRefPtr<nsNameSpaceManager> nsNameSpaceManager::sInstance;
 
 /* static */ nsNameSpaceManager*
 nsNameSpaceManager::GetInstance() {
@@ -52,6 +60,10 @@ nsNameSpaceManager::GetInstance() {
   return sInstance;
 }
 
+nsNameSpaceManager::~nsNameSpaceManager() {
+  mozilla::Preferences::RemoveObservers(this, kObservedPrefs);
+}
+
 bool nsNameSpaceManager::Init()
 {
   nsresult rv;
@@ -73,6 +85,9 @@ bool nsNameSpaceManager::Init()
 
 #undef REGISTER_NAMESPACE
 
+  mozilla::Preferences::AddStrongObservers(this, kObservedPrefs);
+  mIsMathMLDisabled = mozilla::Preferences::GetBool(kMathMLDisabledPrefName);
+
   return true;
 }
 
@@ -151,7 +166,18 @@ NS_NewElement(Element** aResult,
   }
 #endif
   if (ns == kNameSpaceID_MathML) {
-    return NS_NewMathMLElement(aResult, ni.forget());
+    // If the mathml.disabled pref. is true, convert all MathML nodes into
+    // generic XML nodes by swapping the namespace.
+    nsNameSpaceManager* nsmgr = nsNameSpaceManager::GetInstance();
+    if (nsmgr && !nsmgr->mIsMathMLDisabled) {
+      return NS_NewMathMLElement(aResult, ni.forget());
+    }
+
+    nsNodeInfoManager *niMgr = ni->NodeInfoManager();
+    nsCOMPtr<nsINodeInfo> genericXMLNI = niMgr->GetNodeInfo(ni->NameAtom(),
+                                     ni->GetPrefixAtom(), kNameSpaceID_XML,
+                                     ni->NodeType(), ni->GetExtraName());
+    return NS_NewXMLElement(aResult, genericXMLNI.forget());
   }
   if (ns == kNameSpaceID_SVG) {
     return NS_NewSVGElement(aResult, ni.forget(), aFromParser);
@@ -197,3 +223,16 @@ nsresult nsNameSpaceManager::AddNameSpace(const nsAString& aURI,
 
   return NS_OK;
 }
+
+// nsISupports
+NS_IMPL_ISUPPORTS(nsNameSpaceManager,
+                  nsIObserver)
+
+// nsIObserver
+NS_IMETHODIMP
+nsNameSpaceManager::Observe(nsISupports* aObject, const char* aTopic,
+                            const char16_t* aMessage)
+{
+  mIsMathMLDisabled = mozilla::Preferences::GetBool(kMathMLDisabledPrefName);
+  return NS_OK;
+}