ppapi/host/host_message_context.h

   1 // Copyright (c) 2012 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.
   4
   5 #ifndef PPAPI_HOST_HOST_MESSAGE_CONTEXT_H_
   6 #define PPAPI_HOST_HOST_MESSAGE_CONTEXT_H_
   7
   8 #include "ipc/ipc_message.h"
   9 #include "ppapi/host/ppapi_host_export.h"
  10 #include "ppapi/proxy/resource_message_params.h"
  11
  12 namespace ppapi {
  13 namespace host {
  14
  15 // This context structure provides information about outgoing resource message
  16 // replies.
  17 struct PPAPI_HOST_EXPORT ReplyMessageContext {
  18   ReplyMessageContext();
  19   ReplyMessageContext(
  20       const ppapi::proxy::ResourceMessageReplyParams& cp,
  21       IPC::Message* sync_reply_msg,
  22       int routing_id);
  23   ~ReplyMessageContext();
  24
  25   // Returns a value indicating whether this context is valid or "null".
  26   bool is_valid() const { return params.pp_resource() != 0; }
  27
  28   // The "reply params" struct with the same resource and sequence number
  29   // as the original resource message call.
  30   ppapi::proxy::ResourceMessageReplyParams params;
  31
  32   // If this context is generated from a sync message, this will be set to the
  33   // incoming sync message. Otherwise, it will be NULL. The plugin controls
  34   // whether or not the resource call is synchronous or asynchronous so a
  35   // ResoureHost cannot make any assumptions about whether or not this is NULL.
  36   IPC::Message* sync_reply_msg;
  37
  38   // Routing ID to be used when sending a reply message. This is only useful
  39   // when the plugin is in-process. Otherwise, the value will be
  40   // MSG_ROUTING_NONE.
  41   int routing_id;
  42 };
  43
  44 // This context structure provides information about incoming resource message
  45 // call requests when passed to resources.
  46 struct PPAPI_HOST_EXPORT HostMessageContext {
  47   explicit HostMessageContext(
  48       const ppapi::proxy::ResourceMessageCallParams& cp);
  49   HostMessageContext(
  50       int routing_id,
  51       const ppapi::proxy::ResourceMessageCallParams& cp);
  52   HostMessageContext(
  53       const ppapi::proxy::ResourceMessageCallParams& cp,
  54       IPC::Message* sync_reply_msg);
  55   ~HostMessageContext();
  56
  57   // Returns a reply message context struct which includes the reply params.
  58   ReplyMessageContext MakeReplyMessageContext() const;
  59
  60   // The original call parameters passed to the resource message call. This
  61   // cannot be a reference because this object may be passed to another thread.
  62   ppapi::proxy::ResourceMessageCallParams params;
  63
  64   // The reply message. If the params has the callback flag set, this message
  65   // will be sent in reply. It is initialized to the empty message. If the
  66   // handler wants to send something else, it should just assign the message
  67   // it wants to this value.
  68   IPC::Message reply_msg;
  69
  70   // If this context is generated from a sync message, this will be set to the
  71   // incoming sync message. Otherwise, it will be NULL.
  72   IPC::Message* sync_reply_msg;
  73
  74   // Routing ID to be used when sending a reply message. This is only useful
  75   // when the plugin is in-process. Otherwise, the value will be
  76   // MSG_ROUTING_NONE.
  77   int routing_id;
  78 };
  79
  80 }  // namespace host
  81 }  // namespace ppapi
  82
  83 #endif  // PPAPI_HOST_HOST_MESSAGE_CONTEXT_H_