Source/WebKit/Shared/Plugins/PluginQuirks.h

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#pragma once

namespace WebKit {

class PluginQuirks {
public:
    enum PluginQuirk {
        // Mac specific quirks:
#if PLUGIN_ARCHITECTURE(MAC)
        // The plug-in wants the call to getprogname() to return "WebKitPluginHost".
        // Adobe Flash Will not handle key down events otherwise.
        PrognameShouldBeWebKitPluginHost,

        // Supports receiving a paint event, even when using CoreAnimation rendering.
        SupportsSnapshotting,

        // Make the plug-in opaque unless it has a "background" attribute set to a transparent color
        // according to http://msdn.microsoft.com/en-us/library/cc838148(VS.95).aspx
        // A non-existent "background" attribute is interpreted as the named color White which is opaque.
        // Microsoft Silverlight doesn't opt into transparency using NPN_SetValue and
        // NPPVpluginTransparentBool, so we'll always force it unless the plug-in has a "background"
        // attribute that specifies a opaque color.
        MakeOpaqueUnlessTransparentSilverlightBackgroundAttributeExists,

        // Whether calling NPP_GetValue with NPPVpluginCoreAnimationLayer returns a retained Core Animation
        // layer or not. According to the NPAPI specifications, plug-in shouldn't return a retained layer but
        // WebKit1 expects a retained plug-in layer. We use this for Flash to avoid leaking OpenGL layers.
        ReturnsRetainedCoreAnimationLayer,

        // Whether NPP_GetValue with NPPVpluginScriptableNPObject returns a non-retained NPObject or not.
        // Versions of Silverlight prior to 4 never retained the returned NPObject.
        ReturnsNonRetainedScriptableNPObject,

        // Whether the plug-in wants parameter names to be lowercase.
        // <rdar://problem/8440903>: AppleConnect has a bug where it does not
        // understand the parameter names specified in the <object> element that
        // embeds its plug-in. 
        WantsLowercaseParameterNames,

        // Whether to append Version/3.2.1 to the user-agent passed to the plugin
        // This is necessary to disable Silverlight's workaround for a Safari 2 leak
        // which is enabled if it doesn't find Version/3 in the user-agent.
        AppendVersion3UserAgent,

        // Whether all thrown NSExceptions should be leaked.
        // <rdar://problem/13003470> Adobe Flash has a bug where exceptions are released too early.
        LeakAllThrownNSExceptions,

        // X11 specific quirks:
#elif PLATFORM(X11)
        // Flash and npwrapper ask the browser about which GTK version does it use
        // and refuse to load and work if it is not GTK 2 so we need to fake it in
        // NPN_GetValue even when it is a lie.
        RequiresGTKToolKit,

        // Some version 10 releases of Flash run under nspluginwrapper will completely
        // freeze when sending right click events to them in windowed mode.
        IgnoreRightClickInWindowlessMode,

        // Some ports don't support windowed plugins.
        ForceFlashWindowlessMode,

        // Flash crashes when NPP_GetValue is called for NPPVpluginCancelSrcStream in windowed mode.
        DoNotCancelSrcStreamInWindowedMode,
#endif

        // This isn't really a quirk as much as the opposite of a quirk. By default, we don't send wheel events
        // to plug-ins unless we know that they handle them correctly. Adobe Reader on Mac handles wheel events correctly.
        WantsWheelEvents,

        NumPluginQuirks
    };
    
    PluginQuirks()
        : m_quirks(0)
    {
        COMPILE_ASSERT(sizeof(m_quirks) * 8 >= NumPluginQuirks, not_enough_room_for_quirks);
    }
    
    void add(PluginQuirk quirk)
    {
        ASSERT(quirk >= 0);
        RELEASE_ASSERT_WITH_SECURITY_IMPLICATION(quirk < NumPluginQuirks);
        
        m_quirks |= (1 << quirk);
    }
    
    bool contains(PluginQuirk quirk) const
    {
        return m_quirks & (1 << quirk);
    }

private:
    uint32_t m_quirks;
};

} // namespace WebKit