Bug 442809: respect application caches in imgLoader.cpp. r=joedrew, sr=vlad

modules/libpr0n/src/imgLoader.cpp

@@ -64,6 +64,9 @@
 
 #include "nsIComponentRegistrar.h"
 
+#include "nsIApplicationCache.h"
+#include "nsIApplicationCacheContainer.h"
+
 // we want to explore making the document own the load group
 // so we can associate the document URI with the load group.
 // until this point, we have an evil hack:
@@ -865,6 +868,24 @@ PRBool imgLoader::ValidateEntry(imgCacheEntry *aEntry,
     return PR_FALSE;
   }
 
+  // We can't use a cached request if it comes from a different
+  // application cache than this load is expecting.
+  nsCOMPtr<nsIApplicationCacheContainer> appCacheContainer;
+  nsCOMPtr<nsIApplicationCache> requestAppCache;
+  nsCOMPtr<nsIApplicationCache> groupAppCache;
+  if ((appCacheContainer = do_GetInterface(request->mRequest)))
+    appCacheContainer->GetApplicationCache(getter_AddRefs(requestAppCache));
+  if ((appCacheContainer = do_QueryInterface(aLoadGroup)))
+    appCacheContainer->GetApplicationCache(getter_AddRefs(groupAppCache));
+
+  if (requestAppCache != groupAppCache) {
+    PR_LOG(gImgLog, PR_LOG_DEBUG,
+           ("imgLoader::ValidateEntry - Unable to use cached imgRequest "
+            "[request=%p] because of mismatched application caches\n",
+            address_of(request)));
+    return PR_FALSE;
+  }
+
   if (validateRequest && aCanMakeNewChannel) {
     LOG_SCOPE(gImgLog, "imgLoader::ValidateRequest |cache hit| must validate");