Merge Chromium src@r53293

Change-Id: Ia79acf8670f385cee48c45b0a75371d8e950af34

1 files changed, 135 insertions, 0 deletions

diff --git a/webkit/glue/plugins/pepper_resource.h b/webkit/glue/plugins/pepper_resource.h
new file mode 100644
index 0000000..417a06b
--- /dev/null
+++ b/webkit/glue/plugins/pepper_resource.h
@@ -0,0 +1,135 @@
+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef WEBKIT_GLUE_PLUGINS_PEPPER_RESOURCE_H_
+#define WEBKIT_GLUE_PLUGINS_PEPPER_RESOURCE_H_
+
+#include "base/logging.h"
+#include "base/basictypes.h"
+#include "base/ref_counted.h"
+#include "third_party/ppapi/c/pp_resource.h"
+#include "webkit/glue/plugins/pepper_resource_tracker.h"
+
+namespace pepper {
+
+class Buffer;
+class DeviceContext2D;
+class DirectoryReader;
+class FileChooser;
+class FileIO;
+class FileRef;
+class Font;
+class ImageData;
+class PluginModule;
+class Scrollbar;
+class URLLoader;
+class URLRequestInfo;
+class URLResponseInfo;
+class Widget;
+
+class Resource : public base::RefCountedThreadSafe<Resource> {
+ public:
+  explicit Resource(PluginModule* module)  : resource_id_(0), module_(module) {}
+  virtual ~Resource() {}
+
+  // Returns NULL if the resource is invalid or is a different type.
+  template<typename T>
+  static scoped_refptr<T> GetAs(PP_Resource res) {
+    scoped_refptr<Resource> resource = ResourceTracker::Get()->GetResource(res);
+    return resource ? resource->Cast<T>() : NULL;
+  }
+
+  PluginModule* module() const { return module_; }
+
+  // Cast the resource into a specified type. This will return NULL if the
+  // resource does not match the specified type. Specializations of this
+  // template call into As* functions.
+  template <typename T> T* Cast() { return NULL; }
+
+  // Returns an resource id of this object. If the object doesn't have a
+  // resource id, new one is created with plugin refcount of 1. If it does,
+  // the refcount is incremented. Use this when you need to return a new
+  // reference to the plugin.
+  PP_Resource GetReference();
+
+  // When you need to ensure that a resource has a reference, but you do not
+  // want to increase the refcount (for example, if you need to call a plugin
+  // callback function with a reference), you can use this class. For example:
+  //
+  // plugin_callback(.., ScopedResourceId(resource).id, ...);
+  class ScopedResourceId {
+   public:
+    explicit ScopedResourceId(Resource* resource)
+        : id(resource->GetReference()) {}
+    ~ScopedResourceId() {
+      ResourceTracker::Get()->UnrefResource(id);
+    }
+    const PP_Resource id;
+  };
+
+ private:
+  // Type-specific getters for individual resource types. These will return
+  // NULL if the resource does not match the specified type. Used by the Cast()
+  // function.
+  virtual Buffer* AsBuffer() { return NULL; }
+  virtual DeviceContext2D* AsDeviceContext2D() { return NULL; }
+  virtual DirectoryReader* AsDirectoryReader() { return NULL; }
+  virtual FileChooser* AsFileChooser() { return NULL; }
+  virtual FileIO* AsFileIO() { return NULL; }
+  virtual FileRef* AsFileRef() { return NULL; }
+  virtual Font* AsFont() { return NULL; }
+  virtual ImageData* AsImageData() { return NULL; }
+  virtual Scrollbar* AsScrollbar() { return NULL; }
+  virtual URLLoader* AsURLLoader() { return NULL; }
+  virtual URLRequestInfo* AsURLRequestInfo() { return NULL; }
+  virtual URLResponseInfo* AsURLResponseInfo() { return NULL; }
+  virtual Widget* AsWidget() { return NULL; }
+
+ private:
+  // If referenced by a plugin, holds the id of this resource object. Do not
+  // access this member directly, because it is possible that the plugin holds
+  // no references to the object, and therefore the resource_id_ is zero. Use
+  // either GetReference() to obtain a new resource_id and increase the
+  // refcount, or TemporaryReference when you do not want to increase the
+  // refcount.
+  PP_Resource resource_id_;
+
+  // Non-owning pointer to our module.
+  PluginModule* module_;
+
+  // Called by the resource tracker when the last plugin reference has been
+  // dropped.
+  friend class ResourceTracker;
+  void StoppedTracking() {
+    DCHECK(resource_id_ != 0);
+    resource_id_ = 0;
+  }
+
+  DISALLOW_COPY_AND_ASSIGN(Resource);
+};
+
+// Cast() specializations.
+#define DEFINE_RESOURCE_CAST(Type)                   \
+  template <> inline Type* Resource::Cast<Type>() {  \
+      return As##Type();                             \
+  }
+
+DEFINE_RESOURCE_CAST(Buffer)
+DEFINE_RESOURCE_CAST(DeviceContext2D)
+DEFINE_RESOURCE_CAST(DirectoryReader)
+DEFINE_RESOURCE_CAST(FileChooser)
+DEFINE_RESOURCE_CAST(FileIO)
+DEFINE_RESOURCE_CAST(FileRef)
+DEFINE_RESOURCE_CAST(Font)
+DEFINE_RESOURCE_CAST(ImageData)
+DEFINE_RESOURCE_CAST(Scrollbar)
+DEFINE_RESOURCE_CAST(URLLoader)
+DEFINE_RESOURCE_CAST(URLRequestInfo)
+DEFINE_RESOURCE_CAST(URLResponseInfo)
+DEFINE_RESOURCE_CAST(Widget)
+
+#undef DEFINE_RESOURCE_CAST
+}  // namespace pepper
+
+#endif  // WEBKIT_GLUE_PLUGINS_PEPPER_RESOURCE_H_