// Copyright (c) 2011 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 PPAPI_SHARED_IMPL_HOST_RESOURCE_H_
#define PPAPI_SHARED_IMPL_HOST_RESOURCE_H_
#include "ppapi/c/pp_instance.h"
#include "ppapi/c/pp_resource.h"
#include "ppapi/shared_impl/ppapi_shared_export.h"
namespace ppapi {
// For "old" style resources, PP_Resource values differ on the host and plugin
// side. Implementations of those should be careful to use HostResource to
// prevent confusion. "New" style resources use the same PP_Resource value on
// the host and plugin sides, and should not use HostResource.
//
// Old style resources match these file specs:
// Proxy: ppapi/proxy/ppb_*_proxy.*
// Host: webkit/plugins/ppapi/*
// New style resources match these file specs:
// Proxy: ppapi/proxy/*_resource.*
// Browser: (content|chrome)/browser/renderer_host/pepper/pepper_*_host.*
// Renderer: (content|chrome)/renderer/pepper/pepper_*_host.*
//
//
// Represents a PP_Resource sent over the wire. This just wraps a PP_Resource.
// The point is to prevent mistakes where the wrong resource value is sent.
// Resource values are remapped in the plugin so that it can talk to multiple
// hosts. If all values were PP_Resource, it would be easy to forget to do
// this transformation.
//
// To get the corresponding plugin PP_Resource for a HostResource, use
// PluginResourceTracker::PluginResourceForHostResource().
//
// All HostResources respresent IDs valid in the host.
class PPAPI_SHARED_EXPORT HostResource {
public:
HostResource();
bool is_null() const { return !host_resource_; }
// Some resources are plugin-side only and don't have a corresponding
// resource in the host. Yet these resources still need an instance to be
// associated with. This function creates a HostResource with the given
// instances and a 0 host resource ID for these cases.
static HostResource MakeInstanceOnly(PP_Instance instance);
// Sets and retrieves the internal PP_Resource which is valid for the host
// (a.k.a. renderer, as opposed to the plugin) process.
//
// DO NOT CALL THESE FUNCTIONS IN THE PLUGIN SIDE OF THE PROXY. The values
// will be invalid. See the class comment above.
void SetHostResource(PP_Instance instance, PP_Resource resource);
PP_Resource host_resource() const { return host_resource_; }
PP_Instance instance() const { return instance_; }
// This object is used in maps so we need to provide this sorting operator.
bool operator<(const HostResource& other) const {
if (instance_ != other.instance_)
return instance_ < other.instance_;
return host_resource_ < other.host_resource_;
}
private:
PP_Instance instance_;
PP_Resource host_resource_;
};
} // namespace ppapi
#endif // PPAPI_SHARED_IMPL_HOST_RESOURCE_H_