Bug 165893 - avoid refetching the parser service all the time. r=jst@netscape.com, sr=bzbarsky@mit.edu

content/base/public/nsContentUtils.h

@@ -51,6 +51,7 @@ class nsIDocument;
 class nsIDocShell;
 class nsIScriptSecurityManager;
 class nsIThreadJSContextStack;
+class nsIParserService;
 
 
 class nsContentUtils
@@ -204,6 +205,8 @@ public:
   // element.
   static PRBool InProlog(nsIDOMNode *aNode);
 
+  static nsIParserService* GetParserServiceWeakRef();
+  
 private:
   static nsresult doReparentContentWrapper(nsIContent *aChild,
                                            nsIDocument *aNewDocument,
@@ -219,6 +222,9 @@ private:
   static nsIScriptSecurityManager *sSecurityManager;
 
   static nsIThreadJSContextStack *sThreadJSContextStack;
+
+  static nsIParserService *sParserService;
+
 };
 
 

content/base/src/nsContentUtils.cpp

@@ -57,13 +57,18 @@
 #include "nsIJSContextStack.h"
 #include "nsIDocShell.h"
 #include "nsIDocShellTreeItem.h"
+#include "nsParserCIID.h"
+#include "nsIParserService.h"
+#include "nsIServiceManager.h"
 
 static const char *kJSStackContractID = "@mozilla.org/js/xpc/ContextStack;1";
+static NS_DEFINE_IID(kParserServiceCID, NS_PARSERSERVICE_CID);
 
 nsIDOMScriptObjectFactory *nsContentUtils::sDOMScriptObjectFactory = nsnull;
 nsIXPConnect *nsContentUtils::sXPConnect = nsnull;
 nsIScriptSecurityManager *nsContentUtils::sSecurityManager = nsnull;
 nsIThreadJSContextStack *nsContentUtils::sThreadJSContextStack = nsnull;
+nsIParserService *nsContentUtils::sParserService = nsnull;
 
 // static
 nsresult
@@ -88,6 +93,34 @@ nsContentUtils::Init()
   return rv;
 }
 
+/**
+ * Access a cached parser service. Don't addref. We need only one
+ * reference to it and this class has that one.
+ */
+/* static */
+nsIParserService*
+nsContentUtils::GetParserServiceWeakRef()
+{
+  // XXX: This isn't accessed from several threads, is it?
+  if (sParserService == nsnull) {
+    // Lock, recheck sCachedParserService and aquire if this should be
+    // safe for multiple threads.
+    nsCOMPtr<nsIServiceManager> mgr;
+    nsresult rv = NS_GetServiceManager(getter_AddRefs(mgr));
+    
+    if (NS_FAILED(rv))
+      return nsnull;
+
+    // This addrefs the service for us and it will be released in
+    // |Shutdown|.
+    mgr->GetService(kParserServiceCID,
+                    NS_GET_IID(nsIParserService),
+                    NS_REINTERPRET_CAST(void**, &sParserService));
+  }
+
+  return sParserService;
+}
+
 // static
 nsresult
 nsContentUtils::GetStaticScriptGlobal(JSContext* aContext, JSObject* aObj,
@@ -346,6 +379,7 @@ nsContentUtils::Shutdown()
   NS_IF_RELEASE(sXPConnect);
   NS_IF_RELEASE(sSecurityManager);
   NS_IF_RELEASE(sThreadJSContextStack);
+  NS_IF_RELEASE(sParserService);
 }
 
 // static

content/html/document/src/nsHTMLContentSink.cpp

@@ -125,7 +125,6 @@
 #include "nsIScriptGlobalObjectOwner.h"
 
 #include "nsIParserService.h"
-#include "nsParserCIID.h"
 #include "nsISelectElement.h"
 #include "nsITextAreaElement.h"
 
@@ -169,8 +168,6 @@ const PRBool kBlockByDefault = PR_TRUE;
 #endif
 
 
-static NS_DEFINE_IID(kParserServiceCID, NS_PARSERSERVICE_CID);
-
 //----------------------------------------------------------------------
 
 #ifdef NS_DEBUG
@@ -1070,11 +1067,9 @@ NS_CreateHTMLElement(nsIHTMLContent** aResult, nsINodeInfo *aNodeInfo,
 {
   nsresult rv = NS_OK;
 
-  // Cache this service! The XML content sink uses this method!
-
-  nsCOMPtr<nsIParserService> parserService =
-    do_GetService(kParserServiceCID, &rv);
-  NS_ENSURE_SUCCESS(rv, rv);
+  nsIParserService* parserService = nsContentUtils::GetParserServiceWeakRef();
+  if (!parserService)
+    return NS_ERROR_OUT_OF_MEMORY;
 
   nsCOMPtr<nsIAtom> name;
   rv = aNodeInfo->GetNameAtom(*getter_AddRefs(name));
@@ -2546,8 +2541,7 @@ HTMLContentSink::Init(nsIDocument* aDoc,
 
   mObservers = nsnull;
 
-  nsCOMPtr<nsIParserService> service(do_GetService(kParserServiceCID));
-
+  nsIParserService* service = nsContentUtils::GetParserServiceWeakRef();
   if (!service) {
     return NS_ERROR_OUT_OF_MEMORY;
   }