gears/base/npapi/module_wrapper.h

   1 // Copyright 2007, Google Inc.
   2 //
   3 // Redistribution and use in source and binary forms, with or without
   4 // modification, are permitted provided that the following conditions are met:
   5 //
   6 //  1. Redistributions of source code must retain the above copyright notice,
   7 //     this list of conditions and the following disclaimer.
   8 //  2. Redistributions in binary form must reproduce the above copyright notice,
   9 //     this list of conditions and the following disclaimer in the documentation
  10 //     and/or other materials provided with the distribution.
  11 //  3. Neither the name of Google Inc. nor the names of its contributors may be
  12 //     used to endorse or promote products derived from this software without
  13 //     specific prior written permission.
  14 //
  15 // THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
  16 // WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  17 // MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
  18 // EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  19 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  20 // PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  21 // OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
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  24 // ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25
  26 #ifndef GEARS_BASE_NPAPI_MODULE_WRAPPER_H__
  27 #define GEARS_BASE_NPAPI_MODULE_WRAPPER_H__
  28
  29 #include "gears/base/common/base_class.h"
  30 #include "gears/base/npapi/plugin.h"
  31 #include "gears/third_party/scoped_ptr/scoped_ptr.h"
  32
  33 // Base class that implements common functionality to module wrappers.
  34 template<class T>
  35 class ModuleWrapper
  36     : public PluginBase<T>,
  37       public ModuleWrapperBaseClass {
  38  public:
  39   static ModuleWrapperBaseClass *Create(GearsBaseClass *sibling) {
  40     JsContextPtr context = sibling->EnvPageJsContext();
  41     PluginClass *wrapper = static_cast<PluginClass *>(
  42         NPN_CreateObject(context, GetNPClass<PluginClass>()));
  43
  44     if (!wrapper) {
  45       SET_EXCEPTION(STRING16(L"Failed to create requested object."));
  46       return NULL;
  47     }
  48
  49     if (!wrapper->GetImplObject()->InitBaseFromSibling(sibling)) {
  50       SET_EXCEPTION(STRING16(L"Error initializing base class."));
  51       wrapper->Release();
  52       return NULL;
  53     }
  54
  55     return wrapper;
  56   }
  57
  58   ModuleWrapper(NPP instance) :
  59        PluginBase<T>(instance),
  60        impl_(new ImplClass) {
  61     impl_->SetJsWrapper(this);
  62   }
  63
  64   virtual ImplClass *GetImplObject() const { return impl_.get(); }
  65   virtual JsToken GetWrapperToken() const {
  66     NPVariant token;
  67     OBJECT_TO_NPVARIANT(const_cast<ModuleWrapper<T> *>(this), token);
  68     return token;
  69   }
  70   virtual void AddRef() { NPN_RetainObject(this); }
  71   virtual void Release() { NPN_ReleaseObject(this); }
  72
  73  protected:
  74   scoped_ptr<ImplClass> impl_;
  75
  76   DISALLOW_EVIL_CONSTRUCTORS(ModuleWrapper);
  77 };
  78
  79 #endif // GEARS_BASE_NPAPI_MODULE_WRAPPER_H__