ppapi/proxy/plugin_resource.cc

   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 #include "ppapi/proxy/plugin_resource.h"
   6
   7 #include <limits>
   8
   9 #include "ppapi/proxy/ppapi_messages.h"
  10
  11 namespace ppapi {
  12 namespace proxy {
  13
  14 PluginResource::PluginResource(Connection connection, PP_Instance instance)
  15     : Resource(OBJECT_IS_PROXY, instance),
  16       connection_(connection),
  17       next_sequence_number_(1),
  18       sent_create_to_browser_(false),
  19       sent_create_to_renderer_(false) {
  20 }
  21
  22 PluginResource::~PluginResource() {
  23   if (sent_create_to_browser_) {
  24     connection_.browser_sender->Send(
  25         new PpapiHostMsg_ResourceDestroyed(pp_resource()));
  26   }
  27   if (sent_create_to_renderer_) {
  28     connection_.renderer_sender->Send(
  29         new PpapiHostMsg_ResourceDestroyed(pp_resource()));
  30   }
  31 }
  32
  33 void PluginResource::OnReplyReceived(
  34     const proxy::ResourceMessageReplyParams& params,
  35     const IPC::Message& msg) {
  36   TRACE_EVENT2("ppapi proxy", "PluginResource::OnReplyReceived",
  37                "Class", IPC_MESSAGE_ID_CLASS(msg.type()),
  38                "Line", IPC_MESSAGE_ID_LINE(msg.type()));
  39   // Grab the callback for the reply sequence number and run it with |msg|.
  40   CallbackMap::iterator it = callbacks_.find(params.sequence());
  41   if (it == callbacks_.end()) {
  42     DCHECK(false) << "Callback does not exist for an expected sequence number.";
  43   } else {
  44     scoped_refptr<PluginResourceCallbackBase> callback = it->second;
  45     callbacks_.erase(it);
  46     callback->Run(params, msg);
  47   }
  48 }
  49
  50 void PluginResource::NotifyLastPluginRefWasDeleted() {
  51   Resource::NotifyLastPluginRefWasDeleted();
  52
  53   // The callbacks may hold referrences to this object. Normally, we will get
  54   // reply messages from the host side and remove them. However, it is possible
  55   // that some replies from the host never arrive, e.g., the corresponding
  56   // renderer crashes. In that case, we have to clean up the callbacks,
  57   // otherwise this object will live forever.
  58   callbacks_.clear();
  59 }
  60
  61 void PluginResource::NotifyInstanceWasDeleted() {
  62   Resource::NotifyInstanceWasDeleted();
  63
  64   // Please see comments in NotifyLastPluginRefWasDeleted() about why we must
  65   // clean up the callbacks.
  66   // It is possible that NotifyLastPluginRefWasDeleted() is never called for a
  67   // resource. For example, those singleton-style resources such as
  68   // GamepadResource never expose references to the plugin and thus won't
  69   // receive a NotifyLastPluginRefWasDeleted() call. For those resources, we
  70   // need to clean up callbacks when the instance goes away.
  71   callbacks_.clear();
  72 }
  73
  74 void PluginResource::SendCreate(Destination dest, const IPC::Message& msg) {
  75   TRACE_EVENT2("ppapi proxy", "PluginResource::SendCreate",
  76                "Class", IPC_MESSAGE_ID_CLASS(msg.type()),
  77                "Line", IPC_MESSAGE_ID_LINE(msg.type()));
  78   if (dest == RENDERER) {
  79     DCHECK(!sent_create_to_renderer_);
  80     sent_create_to_renderer_ = true;
  81   } else {
  82     DCHECK(!sent_create_to_browser_);
  83     sent_create_to_browser_ = true;
  84   }
  85   ResourceMessageCallParams params(pp_resource(), GetNextSequence());
  86   GetSender(dest)->Send(
  87       new PpapiHostMsg_ResourceCreated(params, pp_instance(), msg));
  88 }
  89
  90 void PluginResource::AttachToPendingHost(Destination dest,
  91                                          int pending_host_id) {
  92   // Connecting to a pending host is a replacement for "create".
  93   if (dest == RENDERER) {
  94     DCHECK(!sent_create_to_renderer_);
  95     sent_create_to_renderer_ = true;
  96   } else {
  97     DCHECK(!sent_create_to_browser_);
  98     sent_create_to_browser_ = true;
  99   }
 100   GetSender(dest)->Send(
 101       new PpapiHostMsg_AttachToPendingHost(pp_resource(), pending_host_id));
 102 }
 103
 104 void PluginResource::Post(Destination dest, const IPC::Message& msg) {
 105   TRACE_EVENT2("ppapi proxy", "PluginResource::Post",
 106                "Class", IPC_MESSAGE_ID_CLASS(msg.type()),
 107                "Line", IPC_MESSAGE_ID_LINE(msg.type()));
 108   ResourceMessageCallParams params(pp_resource(), GetNextSequence());
 109   SendResourceCall(dest, params, msg);
 110 }
 111
 112 bool PluginResource::SendResourceCall(
 113     Destination dest,
 114     const ResourceMessageCallParams& call_params,
 115     const IPC::Message& nested_msg) {
 116   return GetSender(dest)->Send(
 117       new PpapiHostMsg_ResourceCall(call_params, nested_msg));
 118 }
 119
 120 int32_t PluginResource::GenericSyncCall(
 121     Destination dest,
 122     const IPC::Message& msg,
 123     IPC::Message* reply,
 124     ResourceMessageReplyParams* reply_params) {
 125   TRACE_EVENT2("ppapi proxy", "PluginResource::GenericSyncCall",
 126                "Class", IPC_MESSAGE_ID_CLASS(msg.type()),
 127                "Line", IPC_MESSAGE_ID_LINE(msg.type()));
 128   ResourceMessageCallParams params(pp_resource(), GetNextSequence());
 129   params.set_has_callback();
 130   bool success = GetSender(dest)->Send(new PpapiHostMsg_ResourceSyncCall(
 131       params, msg, reply_params, reply));
 132   if (success)
 133     return reply_params->result();
 134   return PP_ERROR_FAILED;
 135 }
 136
 137 int32_t PluginResource::GetNextSequence() {
 138   // Return the value with wraparound, making sure we don't make a sequence
 139   // number with a 0 ID. Note that signed wraparound is undefined in C++ so we
 140   // manually check.
 141   int32_t ret = next_sequence_number_;
 142   if (next_sequence_number_ == std::numeric_limits<int32_t>::max())
 143     next_sequence_number_ = 1;  // Skip 0 which is invalid.
 144   else
 145     next_sequence_number_++;
 146   return ret;
 147 }
 148
 149 }  // namespace proxy
 150 }  // namespace ppapi