1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #ifndef PPAPI_SHARED_IMPL_HOST_RESOURCE_H_
6 #define PPAPI_SHARED_IMPL_HOST_RESOURCE_H_
8 #include "ppapi/c/pp_instance.h"
9 #include "ppapi/c/pp_resource.h"
10 #include "ppapi/shared_impl/ppapi_shared_export.h"
14 // For "old" style resources, PP_Resource values differ on the host and plugin
15 // side. Implementations of those should be careful to use HostResource to
16 // prevent confusion. "New" style resources use the same PP_Resource value on
17 // the host and plugin sides, and should not use HostResource.
19 // Old style resources match these file specs:
20 // Proxy: ppapi/proxy/ppb_*_proxy.*
21 // Host: webkit/plugins/ppapi/*
22 // New style resources match these file specs:
23 // Proxy: ppapi/proxy/*_resource.*
24 // Browser: (content|chrome)/browser/renderer_host/pepper/pepper_*_host.*
25 // Renderer: (content|chrome)/renderer/pepper/pepper_*_host.*
28 // Represents a PP_Resource sent over the wire. This just wraps a PP_Resource.
29 // The point is to prevent mistakes where the wrong resource value is sent.
30 // Resource values are remapped in the plugin so that it can talk to multiple
31 // hosts. If all values were PP_Resource, it would be easy to forget to do
32 // this transformation.
34 // To get the corresponding plugin PP_Resource for a HostResource, use
35 // PluginResourceTracker::PluginResourceForHostResource().
37 // All HostResources respresent IDs valid in the host.
38 class PPAPI_SHARED_EXPORT HostResource {
42 bool is_null() const {
43 return !host_resource_;
46 // Some resources are plugin-side only and don't have a corresponding
47 // resource in the host. Yet these resources still need an instance to be
48 // associated with. This function creates a HostResource with the given
49 // instances and a 0 host resource ID for these cases.
50 static HostResource MakeInstanceOnly(PP_Instance instance);
52 // Sets and retrieves the internal PP_Resource which is valid for the host
53 // (a.k.a. renderer, as opposed to the plugin) process.
55 // DO NOT CALL THESE FUNCTIONS IN THE PLUGIN SIDE OF THE PROXY. The values
56 // will be invalid. See the class comment above.
57 void SetHostResource(PP_Instance instance, PP_Resource resource);
58 PP_Resource host_resource() const {
59 return host_resource_;
62 PP_Instance instance() const { return instance_; }
64 // This object is used in maps so we need to provide this sorting operator.
65 bool operator<(const HostResource& other) const {
66 if (instance_ != other.instance_)
67 return instance_ < other.instance_;
68 return host_resource_ < other.host_resource_;
72 PP_Instance instance_;
73 PP_Resource host_resource_;
78 #endif // PPAPI_SHARED_IMPL_HOST_RESOURCE_H_