[HBD] Remove PluginCache and reload plugin list when origin changes

third_party/WebKit/Source/platform/plugins/PluginData.cpp

 /*
     Copyright (C) 2000 Harri Porten (porten@kde.org)
     Copyright (C) 2000 Daniel Molkentin (molkentin@kde.org)
     Copyright (C) 2000 Stefan Schimanski (schimmi@kde.org)
     Copyright (C) 2003, 2004, 2005, 2006, 2007 Apple Inc. All Rights Reserved.
     Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
 
     This library is free software; you can redistribute it and/or
     modify it under the terms of the GNU Library General Public
     License as published by the Free Software Foundation; either
     version 2 of the License, or (at your option) any later version.
 
     This library is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     Library General Public License for more details.
 
     You should have received a copy of the GNU Library General Public License
     along with this library; see the file COPYING.LIB.  If not, write to
     the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
     Boston, MA 02110-1301, USA.
 */
 
 #include "platform/plugins/PluginData.h"
 
 #include "platform/plugins/PluginListBuilder.h"
+#include "platform/weborigin/SecurityOrigin.h"
 #include "public/platform/Platform.h"
+#include "public/platform/WebSecurityOrigin.h"
 
 namespace blink {
 
-class PluginCache {
-public:
-    PluginCache() : m_loaded(false), m_refresh(false) { }
-    ~PluginCache() { reset(false); }
-
-    void reset(bool refresh)
-    {
-        m_plugins.clear();
-        m_loaded = false;
-        m_refresh = refresh;
-    }
-
-    const Vector<PluginInfo>& plugins()
-    {
-        if (!m_loaded) {
-            PluginListBuilder builder(&m_plugins);
-            Platform::current()->getPluginList(m_refresh, &builder);
-            m_loaded = true;
-            m_refresh = false;
-        }
-        return m_plugins;
-    }
-
-private:
-    Vector<PluginInfo> m_plugins;
-    bool m_loaded;
-    bool m_refresh;
-};
-
-static PluginCache& pluginCache()
+PluginData::PluginData(SecurityOrigin* mainFrameOrigin)
+    : m_mainFrameOrigin(mainFrameOrigin)
 {
-    DEFINE_STATIC_LOCAL(PluginCache, cache, ());
-    return cache;
-}
-
-PluginData::PluginData(const Page* page)
-{
-    initPlugins(page);
+    PluginListBuilder builder(&m_plugins);
+    Platform::current()->getPluginList(m_refresh, WebSecurityOrigin(m_mainFrameOrigin), &builder);

[esprehn, 2016/08/26 04:46:03]

I don't understand how this code can work, you're using a static variable
m_refresh here, but looking at the main frame origin, but the static is shared
per process. This can't work

[trizzofo, 2016/08/26 20:28:00]

It's confusing, but PluginData::refresh() is actually used to refresh the plugin
list in the browser side. It ends up calling PluginServiceImpl::RefreshPlugin()
here:

https://cs.chromium.org/chromium/src/content/browser/frame_host/render_frame_...

Looking at the current code, as far as I can understand, the desired effect is
that, after PluginData::refresh() is called, the plugin list on the browser side
is updated and all new instances of PluginData in the process that called
PluginData::refresh() have the updated list of plugins.

Since PluginCache is per-process, I believe that a static boolean will have the
same effect. The only behavioral difference I noticed in my code is that the
browser process plugin list is updated only when a new PluginData is
instantiated, but the current code sends an IPC to the browser process and
update it right away.

[tommycli, 2016/08/26 20:34:16]

Yes - after refresh() is called, all existing PluginData instances must re-read
the list of plugins, so we indeed want a static variable.

refresh() could probably be renamed rereadPluginListFromDisk() and s_refresh
could be renamed s_needsRereadFromDisk. Would that be clearer, esprehn?

[trizzofo, 2016/08/26 22:19:41]

Actually, when PluginData::refresh() is called, all existing PluginData
instances remain untouched. The only effect is that new instances will have the
updated list provided by the browser process.

+    m_refresh = false;

[esprehn, 2016/08/26 04:46:03]

What about all of the other frames?

[trizzofo, 2016/08/26 20:28:00]

New instances of PluginData will have the updated list of plugins.

 
     for (unsigned i = 0; i < m_plugins.size(); ++i) {
         const PluginInfo& plugin = m_plugins[i];
         for (unsigned j = 0; j < plugin.mimes.size(); ++j) {
             m_mimes.append(plugin.mimes[j]);
             m_mimePluginIndices.append(i);
         }
     }
 }
 
@@ skipping 17 matching lines @@
     return 0;
 }
 
 String PluginData::pluginNameForMimeType(const String& mimeType) const
 {
     if (const PluginInfo* info = pluginInfoForMimeType(mimeType))
         return info->name;
     return String();
 }
 
-void PluginData::initPlugins(const Page*)
-{
-    const Vector<PluginInfo>& plugins = pluginCache().plugins();
-    for (size_t i = 0; i < plugins.size(); ++i)
-        m_plugins.append(plugins[i]);
-}
-
 void PluginData::refresh()
 {
-    pluginCache().reset(true);
-    pluginCache().plugins(); // Force the plugins to be reloaded now.
+    m_refresh = true;
 }
 
+bool PluginData::m_refresh = false;
+
 } // namespace blink