Bug 882339 - Cache the blocklist state on plugin tags to avoid querying the blocklist service constantly, r=johns

browser/base/content/test/head.js

@@ -115,8 +115,8 @@ function updateBlocklist(aCallback) {
   var blocklistNotifier = Cc["@mozilla.org/extensions/blocklist;1"]
                           .getService(Ci.nsITimerCallback);
   var observer = function() {
-    aCallback();
     Services.obs.removeObserver(observer, "blocklist-updated");
+    SimpleTest.executeSoon(aCallback);
   };
   Services.obs.addObserver(observer, "blocklist-updated", false);
   blocklistNotifier.notify(null);

content/base/test/chrome/test_bug391728.html

@@ -58,8 +58,8 @@ function updateBlocklist(aCallback) {
   var blocklistNotifier = Components.classes["@mozilla.org/extensions/blocklist;1"]
                           .getService(Components.interfaces.nsITimerCallback);
   var observer = function() {
-    aCallback();
     Services.obs.removeObserver(observer, "blocklist-updated");
+    SimpleTest.executeSoon(aCallback);
   };
   Services.obs.addObserver(observer, "blocklist-updated", false);
   blocklistNotifier.notify(null);

dom/plugins/base/nsPluginHost.cpp

@@ -292,6 +292,7 @@ nsPluginHost::nsPluginHost()
     mozilla::services::GetObserverService();
   if (obsService) {
     obsService->AddObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID, false);
+    obsService->AddObserver(this, "blocklist-updated", false);
 #ifdef MOZ_WIDGET_ANDROID
     obsService->AddObserver(this, "application-foreground", false);
     obsService->AddObserver(this, "application-background", false);
@@ -1068,17 +1069,12 @@ nsPluginHost::GetBlocklistStateForType(const char *aMimeType, uint32_t *aState)
   if (!plugin) {
     plugin = FindPluginForType(aMimeType, false);
   }
-  if (plugin) {
-    nsCOMPtr<nsIBlocklistService> blocklist = do_GetService("@mozilla.org/extensions/blocklist;1");
-    if (blocklist) {
-      // The EmptyString()s are so we use the currently running application
-      // and toolkit versions
-      return blocklist->GetPluginBlocklistState(plugin, EmptyString(),
-                                                EmptyString(), aState);
-    }
+  if (!plugin) {
+    return NS_ERROR_FAILURE;
   }
 
-  return NS_ERROR_FAILURE;
+  *aState = plugin->GetBlocklistState();
+  return NS_OK;
 }
 
 NS_IMETHODIMP
@@ -1931,25 +1927,17 @@ nsresult nsPluginHost::ScanPluginsDirectory(nsIFile *pluginsDir,
 
       pluginTag->mLibrary = library;
       pluginTag->mLastModifiedTime = fileModTime;
+      uint32_t state = pluginTag->GetBlocklistState();
 
-      nsCOMPtr<nsIBlocklistService> blocklist = do_GetService("@mozilla.org/extensions/blocklist;1");
-      if (blocklist) {
-        uint32_t state;
-        rv = blocklist->GetPluginBlocklistState(pluginTag, EmptyString(),
-                                                EmptyString(), &state);
-
-        if (NS_SUCCEEDED(rv)) {
-          // If the blocklist says it is risky and we have never seen this
-          // plugin before, then disable it.
-          // If the blocklist says this is an outdated plugin, warn about
-          // outdated plugins.
-          if (state == nsIBlocklistService::STATE_SOFTBLOCKED && !seenBefore) {
-             pluginTag->SetEnabledState(nsIPluginTag::STATE_DISABLED);
-          }
-          if (state == nsIBlocklistService::STATE_OUTDATED && !seenBefore) {
-             warnOutdated = true;
-          }
-        }
+      // If the blocklist says it is risky and we have never seen this
+      // plugin before, then disable it.
+      // If the blocklist says this is an outdated plugin, warn about
+      // outdated plugins.
+      if (state == nsIBlocklistService::STATE_SOFTBLOCKED && !seenBefore) {
+        pluginTag->SetEnabledState(nsIPluginTag::STATE_DISABLED);
+      }
+      if (state == nsIBlocklistService::STATE_OUTDATED && !seenBefore) {
+        warnOutdated = true;
       }
 
       // Plugin unloading is tag-based. If we created a new tag and loaded
@@ -3146,12 +3134,12 @@ NS_IMETHODIMP nsPluginHost::Observe(nsISupports *aSubject,
                                     const char *aTopic,
                                     const PRUnichar *someData)
 {
-  if (!nsCRT::strcmp(NS_XPCOM_SHUTDOWN_OBSERVER_ID, aTopic)) {
+  if (!strcmp(NS_XPCOM_SHUTDOWN_OBSERVER_ID, aTopic)) {
     OnShutdown();
     UnloadPlugins();
     sInst->Release();
   }
-  if (!nsCRT::strcmp(NS_PREFBRANCH_PREFCHANGE_TOPIC_ID, aTopic)) {
+  if (!strcmp(NS_PREFBRANCH_PREFCHANGE_TOPIC_ID, aTopic)) {
     mPluginsDisabled = Preferences::GetBool("plugin.disable", false);
     mPluginsClickToPlay = Preferences::GetBool("plugins.click_to_play", false);
     // Unload or load plugins as needed
@@ -3161,19 +3149,26 @@ NS_IMETHODIMP nsPluginHost::Observe(nsISupports *aSubject,
       LoadPlugins();
     }
   }
+  if (!strcmp("blocklist-updated", aTopic)) {
+    nsPluginTag* plugin = mPlugins;
+    while (plugin) {
+      plugin->InvalidateBlocklistState();
+      plugin = plugin->mNext;
+    }
+  }
 #ifdef MOZ_WIDGET_ANDROID
-  if (!nsCRT::strcmp("application-background", aTopic)) {
+  if (!strcmp("application-background", aTopic)) {
     for(uint32_t i = 0; i < mInstances.Length(); i++) {
       mInstances[i]->NotifyForeground(false);
     }
   }
-  if (!nsCRT::strcmp("application-foreground", aTopic)) {
+  if (!strcmp("application-foreground", aTopic)) {
     for(uint32_t i = 0; i < mInstances.Length(); i++) {
       if (mInstances[i]->IsOnScreen())
         mInstances[i]->NotifyForeground(true);
     }
   }
-  if (!nsCRT::strcmp("memory-pressure", aTopic)) {
+  if (!strcmp("memory-pressure", aTopic)) {
     for(uint32_t i = 0; i < mInstances.Length(); i++) {
       mInstances[i]->MemoryPressure();
     }

dom/plugins/base/nsPluginTags.cpp

@@ -80,7 +80,9 @@ nsPluginTag::nsPluginTag(nsPluginTag* aPluginTag)
     mFullPath(aPluginTag->mFullPath),
     mVersion(aPluginTag->mVersion),
     mLastModifiedTime(0),
-    mNiceFileName()
+    mNiceFileName(),
+    mCachedBlocklistState(nsIBlocklistService::STATE_NOT_BLOCKED),
+    mCachedBlocklistStateValid(false)
 {
 }
 
@@ -94,7 +96,9 @@ nsPluginTag::nsPluginTag(nsPluginInfo* aPluginInfo)
     mFullPath(aPluginInfo->fFullPath),
     mVersion(aPluginInfo->fVersion),
     mLastModifiedTime(0),
-    mNiceFileName()
+    mNiceFileName(),
+    mCachedBlocklistState(nsIBlocklistService::STATE_NOT_BLOCKED),
+    mCachedBlocklistStateValid(false)
 {
   InitMime(aPluginInfo->fMimeTypeArray,
            aPluginInfo->fMimeDescriptionArray,
@@ -123,7 +127,9 @@ nsPluginTag::nsPluginTag(const char* aName,
     mFullPath(aFullPath),
     mVersion(aVersion),
     mLastModifiedTime(aLastModifiedTime),
-    mNiceFileName()
+    mNiceFileName(),
+    mCachedBlocklistState(nsIBlocklistService::STATE_NOT_BLOCKED),
+    mCachedBlocklistStateValid(false)
 {
   InitMime(aMimeTypes, aMimeDescriptions, aExtensions,
            static_cast<uint32_t>(aVariants));
@@ -538,3 +544,35 @@ void nsPluginTag::ImportFlagsToPrefs(uint32_t flags)
     SetPluginState(ePluginState_Disabled);
   }
 }
+
+uint32_t
+nsPluginTag::GetBlocklistState()
+{
+  if (mCachedBlocklistStateValid) {
+    return mCachedBlocklistState;
+  }
+
+  nsCOMPtr<nsIBlocklistService> blocklist = do_GetService("@mozilla.org/extensions/blocklist;1");
+  if (!blocklist) {
+    return nsIBlocklistService::STATE_NOT_BLOCKED;
+  }
+
+  // The EmptyString()s are so we use the currently running application
+  // and toolkit versions
+  uint32_t state;
+  if (NS_FAILED(blocklist->GetPluginBlocklistState(this, EmptyString(),
+                                                   EmptyString(), &state))) {
+    return nsIBlocklistService::STATE_NOT_BLOCKED;
+  }
+
+  MOZ_ASSERT(state <= UINT16_MAX);
+  mCachedBlocklistState = (uint16_t) state;
+  mCachedBlocklistStateValid = true;
+  return state;
+}
+
+void
+nsPluginTag::InvalidateBlocklistState()
+{
+  mCachedBlocklistStateValid = false;
+}

dom/plugins/base/nsPluginTags.h

@@ -85,8 +85,14 @@ public:
   nsCString     mVersion;  // UTF-8
   int64_t       mLastModifiedTime;
   nsCOMPtr<nsITimer> mUnloadTimer;
+
+  uint32_t      GetBlocklistState();
+  void          InvalidateBlocklistState();
+
 private:
   nsCString     mNiceFileName; // UTF-8
+  uint16_t      mCachedBlocklistState;
+  bool          mCachedBlocklistStateValid;
 
   void InitMime(const char* const* aMimeTypes,
                 const char* const* aMimeDescriptions,

toolkit/mozapps/extensions/test/browser/browser_CTP_plugins.js

@@ -11,8 +11,8 @@ function updateBlocklist(aCallback) {
   var blocklistNotifier = Cc["@mozilla.org/extensions/blocklist;1"]
                           .getService(Ci.nsITimerCallback);
   var observer = function() {
-    aCallback();
     Services.obs.removeObserver(observer, "blocklist-updated");
+    SimpleTest.executeSoon(aCallback);
   };
   Services.obs.addObserver(observer, "blocklist-updated", false);
   blocklistNotifier.notify(null);