fixes bug 210208 "add http-on-examine-merged-response notification" patch=rggammon@alumni.uwaterloo.ca r+sr=darin

netwerk/protocol/http/public/nsIHttpProtocolHandler.idl

@@ -133,4 +133,11 @@ interface nsIHttpProtocolHandler : nsIProxiedProtocolHandler
  * the notification is the nsIHttpChannel instance.
  */
 #define NS_HTTP_ON_EXAMINE_RESPONSE_TOPIC "http-on-examine-response"
+
+/**
+ * The observer of this topic is notified after the received HTTP response
+ * is merged with data from the browser cache.  This means that, among other
+ * things, the Content-Type header will be set correctly.
+ */
+#define NS_HTTP_ON_EXAMINE_MERGED_RESPONSE_TOPIC "http-on-examine-merged-response"
 %}

netwerk/protocol/http/src/nsHttpChannel.cpp

@@ -654,8 +654,7 @@ nsHttpChannel::ProcessResponse()
     SetCookie(mResponseHead->PeekHeader(nsHttp::Set_Cookie));
 
     // notify nsIHttpNotify implementations
-    rv = gHttpHandler->OnExamineResponse(this);
-    NS_ASSERTION(NS_SUCCEEDED(rv), "OnExamineResponse failed");
+    gHttpHandler->OnExamineResponse(this);
 
     // handle different server response categories
     switch (httpStatus) {
@@ -976,6 +975,10 @@ nsHttpChannel::ProcessPartialContent()
     rv = UpdateExpirationTime();
     if (NS_FAILED(rv)) return rv;
 
+    // notify observers interested in looking at a reponse that has been
+    // merged with any cached headers
+    gHttpHandler->OnExamineMergedResponse(this);
+
     // the cached content is valid, although incomplete.
     mCachedContentIsValid = PR_TRUE;
     return ReadFromCache();
@@ -1050,6 +1053,10 @@ nsHttpChannel::ProcessNotModified()
     rv = UpdateExpirationTime();
     if (NS_FAILED(rv)) return rv;
 
+    // notify observers interested in looking at a reponse that has been
+    // merged with any cached headers
+    gHttpHandler->OnExamineMergedResponse(this);
+
     mCachedContentIsValid = PR_TRUE;
     rv = ReadFromCache();
     if (NS_FAILED(rv)) return rv;
@@ -2748,8 +2755,7 @@ nsHttpChannel::AsyncOpen(nsIStreamListener *listener, nsISupports *context)
     AddCookiesToRequest();
 
     // Notify nsIHttpNotify implementations
-    rv = gHttpHandler->OnModifyRequest(this);
-    NS_ASSERTION(NS_SUCCEEDED(rv), "OnModifyRequest failed");
+    gHttpHandler->OnModifyRequest(this);
     
     mIsPending = PR_TRUE;
 
@@ -3660,8 +3666,7 @@ nsHttpChannel::DoAuthRetry(nsAHttpConnection *conn)
     AddCookiesToRequest();
 
     // notify nsIHttpNotify implementations
-    rv = gHttpHandler->OnModifyRequest(this);
-    NS_ASSERTION(NS_SUCCEEDED(rv), "OnModifyRequest failed");
+    gHttpHandler->OnModifyRequest(this);
 
     mIsPending = PR_TRUE;
 

netwerk/protocol/http/src/nsHttpHandler.cpp

@@ -471,22 +471,12 @@ nsHttpHandler::GetIOService(nsIIOService** result)
 }
 
 
-nsresult
-nsHttpHandler::OnModifyRequest(nsIHttpChannel *chan)
+void
+nsHttpHandler::NotifyObservers(nsIHttpChannel *chan, const char *event)
 {
-    LOG(("nsHttpHandler::OnModifyRequest [chan=%x]\n", chan));
+    LOG(("nsHttpHandler::NotifyObservers [chan=%x event=\"%s\"]\n", chan, event));
     if (mObserverService)
-        mObserverService->NotifyObservers(chan, NS_HTTP_ON_MODIFY_REQUEST_TOPIC, nsnull);
-    return NS_OK;
-}
-
-nsresult
-nsHttpHandler::OnExamineResponse(nsIHttpChannel *chan)
-{
-    LOG(("nsHttpHandler::OnExamineResponse [chan=%x]\n", chan));
-    if (mObserverService)
-        mObserverService->NotifyObservers(chan, NS_HTTP_ON_EXAMINE_RESPONSE_TOPIC, nsnull);
-    return NS_OK;
+        mObserverService->NotifyObservers(chan, event, nsnull);
 }
 
 //-----------------------------------------------------------------------------

netwerk/protocol/http/src/nsHttpHandler.h

@@ -156,10 +156,22 @@ public:
     nsICookieService * GetCookieService(); // not addrefed
 
     // Called by the channel before writing a request
-    nsresult OnModifyRequest(nsIHttpChannel *);
+    void OnModifyRequest(nsIHttpChannel *chan)
+    {
+        NotifyObservers(chan, NS_HTTP_ON_MODIFY_REQUEST_TOPIC);
+    }
 
     // Called by the channel once headers are available
-    nsresult OnExamineResponse(nsIHttpChannel *);
+    void OnExamineResponse(nsIHttpChannel *chan)
+    {
+        NotifyObservers(chan, NS_HTTP_ON_EXAMINE_RESPONSE_TOPIC);
+    }
+
+    // Called by the channel once headers have been merged with cached headers
+    void OnExamineMergedResponse(nsIHttpChannel *chan)
+    {
+        NotifyObservers(chan, NS_HTTP_ON_EXAMINE_MERGED_RESPONSE_TOPIC);
+    }
 
 private:
 
@@ -176,13 +188,12 @@ private:
     nsresult SetAcceptEncodings(const char *);
     nsresult SetAcceptCharsets(const char *);
 
-    // timer callback for cleansing the idle connection list
-    //static void DeadConnectionCleanupCB(nsITimer *, void *);
-
     nsresult InitConnectionMgr();
     void     StartPruneDeadConnectionsTimer();
     void     StopPruneDeadConnectionsTimer();
 
+    void     NotifyObservers(nsIHttpChannel *chan, const char *event);
+
 private:
 
     // cached services