fixes bug 102743 "Crash pressing Back or Forward on O'Reilly website"

r=gagan, sr=rpotts

modules/libpr0n/src/imgLoader.cpp

@@ -445,6 +445,13 @@ ProxyListener::~ProxyListener()
 /* void onStartRequest (in nsIRequest request, in nsISupports ctxt); */
 NS_IMETHODIMP ProxyListener::OnStartRequest(nsIRequest *aRequest, nsISupports *ctxt)
 {
+  // if the request has been redirected, then we'll get another pair
+  // of OnStartRequest/OnStopRequest from the new request.
+  nsresult status = 0;
+  aRequest->GetStatus(&status);
+  if (status == NS_BINDING_REDIRECTED)
+    return NS_OK;
+
   if (!mDestListener)
     return NS_ERROR_FAILURE;
 
@@ -483,6 +490,11 @@ NS_IMETHODIMP ProxyListener::OnStartRequest(nsIRequest *aRequest, nsISupports *c
 /* void onStopRequest (in nsIRequest request, in nsISupports ctxt, in nsresult status); */
 NS_IMETHODIMP ProxyListener::OnStopRequest(nsIRequest *aRequest, nsISupports *ctxt, nsresult status)
 {
+  // if the request has been redirected, then we'll get another pair
+  // of OnStartRequest/OnStopRequest from the new request.
+  if (status == NS_BINDING_REDIRECTED)
+    return NS_OK;
+
   if (!mDestListener)
     return NS_ERROR_FAILURE;
 

netwerk/base/public/nsIRequestObserver.idl

@@ -80,7 +80,8 @@ interface nsIRequestObserver : nsISupports
 #define NS_BINDING_FAILED    NS_ERROR_GENERATE_FAILURE(NS_ERROR_MODULE_NETWORK, 1)
 #define NS_BINDING_ABORTED   NS_ERROR_GENERATE_FAILURE(NS_ERROR_MODULE_NETWORK, 2)
 
-// The binding has been moved to another request in the same load group:
+// The binding has been moved to another request in the same load group;
+// the request observer should expect another On{Start/Stop}Request pair:
 #define NS_BINDING_REDIRECTED NS_ERROR_GENERATE_FAILURE(NS_ERROR_MODULE_NETWORK, 3)
 
 // The binding has been moved to another request in a different load group:

netwerk/base/src/nsDownloader.cpp

@@ -128,6 +128,11 @@ NS_IMETHODIMP
 nsDownloader::OnStopRequest(nsIRequest *request, nsISupports *ctxt,
                               nsresult aStatus)
 {
+  // if the request has been redirected, then we'll get another pair
+  // of OnStartRequest/OnStopRequest from the new request.
+  if (aStatus == NS_BINDING_REDIRECTED)
+    return NS_OK;
+
   nsCOMPtr<nsIFile> file;
   if (NS_SUCCEEDED(aStatus))
   {

netwerk/base/src/nsStreamLoader.cpp

@@ -111,9 +111,9 @@ nsStreamLoader::GetNumBytesRead(PRUint32* aNumBytes)
 
 /* readonly attribute nsIRequest request; */
 NS_IMETHODIMP 
-nsStreamLoader::GetRequest(nsIRequest * *aRequest)
+nsStreamLoader::GetRequest(nsIRequest **aRequest)
 {
-    NS_IF_ADDREF(*aRequest=mRequest);
+    NS_IF_ADDREF(*aRequest = mRequest);
     return NS_OK;
 }
 
@@ -128,14 +128,19 @@ NS_IMETHODIMP
 nsStreamLoader::OnStopRequest(nsIRequest* request, nsISupports *ctxt,
                               nsresult aStatus)
 {
-  nsresult rv;
-  mRequest = request;
-  if (mObserver) {
-    rv = mObserver->OnStreamComplete(this, mContext, aStatus, 
-                                     mData.Length(),
-                                     mData.get());
+  // if the request has been redirected, then we'll get another pair
+  // of OnStartRequest/OnStopRequest from the new request.
+  if ((aStatus != NS_BINDING_REDIRECTED) && mObserver) {
+    // provide nsIStreamLoader::request during call to OnStreamComplete
+    mRequest = request;
+    mObserver->OnStreamComplete(this, mContext, aStatus, 
+                                mData.Length(), mData.get());
+    // done.. cleanup
+    mRequest = 0;
+    mObserver = 0;
+    mContext = 0;
   }
-  return rv;
+  return NS_OK;
 }
 
 #define BUF_SIZE 1024

netwerk/base/src/nsURIChecker.cpp

@@ -177,9 +177,13 @@ NS_IMETHODIMP nsURIChecker::SetLoadFlags(nsLoadFlags aLoadFlags)
 NS_IMETHODIMP
 nsURIChecker::OnStartRequest(nsIRequest *aRequest, nsISupports *aCtxt)
 {
-    // DNS errors and other obvious problems will return failure status
     nsresult status;
     nsresult rv = aRequest->GetStatus(&status);
+    // if the request has been redirected, then we'll get another pair
+    // of OnStartRequest/OnStopRequest from the new request.
+    if (status == NS_BINDING_REDIRECTED)
+        return NS_OK;
+    // DNS errors and other obvious problems will return failure status
     if (NS_FAILED(rv) || NS_FAILED(status)) {
         SetStatusAndCallBack(NS_BINDING_FAILED);
         return NS_OK;

netwerk/protocol/http/src/nsHttpChannel.cpp

@@ -116,8 +116,6 @@ nsHttpChannel::Init(nsIURI *uri,
     mOriginalURI = uri;
     mCapabilities = caps;
 
-    LOG(("uri=%s\n", mSpec.get()));
-
     //
     // Construct connection info object
     //
@@ -155,6 +153,8 @@ nsHttpChannel::Init(nsIURI *uri,
     rv = mURI->GetSpec(getter_Copies(mSpec));
     if (NS_FAILED(rv)) return rv;
 
+    LOG(("uri=%s\n", mSpec.get()));
+
     mConnectionInfo = new nsHttpConnectionInfo(host, port,
                                                proxyInfo, usingSSL);
     if (!mConnectionInfo)
@@ -1231,12 +1231,11 @@ nsHttpChannel::ProcessRedirection(PRUint32 redirectType)
 
     // close down this transaction (null if processing a cached redirect)
     if (mTransaction) {
+        mStatus = NS_BINDING_REDIRECTED;
         mTransaction->Cancel(NS_BINDING_REDIRECTED);
-
-        // disconnect from our listener
-        mListener = 0;
-        mListenerContext = 0;
+        mListener->OnStartRequest(this, mListenerContext);
     }
+
     return NS_OK;
 }
 
@@ -1692,7 +1691,7 @@ NS_IMETHODIMP
 nsHttpChannel::GetName(PRUnichar **aName)
 {
     NS_ENSURE_ARG_POINTER(aName);
-    *aName = ToNewUnicode(NS_ConvertASCIItoUCS2(mSpec));
+    *aName = ToNewUnicode(mSpec);
     return NS_OK;
 }