src/ppapi/host/ppapi_host.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/host/ppapi_host.h"
   6
   7 #include "base/logging.h"
   8 #include "ppapi/c/pp_errors.h"
   9 #include "ppapi/host/host_factory.h"
  10 #include "ppapi/host/host_message_context.h"
  11 #include "ppapi/host/instance_message_filter.h"
  12 #include "ppapi/host/resource_host.h"
  13 #include "ppapi/proxy/ppapi_messages.h"
  14 #include "ppapi/proxy/resource_message_params.h"
  15 #include "ppapi/shared_impl/host_resource.h"
  16
  17 namespace ppapi {
  18 namespace host {
  19
  20 namespace {
  21
  22 // Put a cap on the maximum number of resources so we don't explode if the
  23 // renderer starts spamming us.
  24 const size_t kMaxResourcesPerPlugin = 1 << 14;
  25
  26 }  // namespace
  27
  28 PpapiHost::PpapiHost(IPC::Sender* sender,
  29                      const PpapiPermissions& perms)
  30     : sender_(sender),
  31       permissions_(perms),
  32       next_pending_resource_host_id_(1) {
  33 }
  34
  35 PpapiHost::~PpapiHost() {
  36   // Delete these explicitly before destruction since then the host is still
  37   // technically alive in case one of the filters accesses us from the
  38   // destructor.
  39   instance_message_filters_.clear();
  40
  41   // The resources may also want to use us in their destructors.
  42   resources_.clear();
  43   pending_resource_hosts_.clear();
  44 }
  45
  46 bool PpapiHost::Send(IPC::Message* msg) {
  47   return sender_->Send(msg);
  48 }
  49
  50 bool PpapiHost::OnMessageReceived(const IPC::Message& msg) {
  51   bool handled = true;
  52   IPC_BEGIN_MESSAGE_MAP(PpapiHost, msg)
  53     IPC_MESSAGE_HANDLER(PpapiHostMsg_ResourceCall,
  54                         OnHostMsgResourceCall)
  55     IPC_MESSAGE_HANDLER(PpapiHostMsg_InProcessResourceCall,
  56                         OnHostMsgInProcessResourceCall)
  57     IPC_MESSAGE_HANDLER_DELAY_REPLY(PpapiHostMsg_ResourceSyncCall,
  58                                     OnHostMsgResourceSyncCall)
  59     IPC_MESSAGE_HANDLER(PpapiHostMsg_ResourceCreated,
  60                         OnHostMsgResourceCreated)
  61     IPC_MESSAGE_HANDLER(PpapiHostMsg_AttachToPendingHost,
  62                         OnHostMsgAttachToPendingHost)
  63     IPC_MESSAGE_HANDLER(PpapiHostMsg_ResourceDestroyed,
  64                         OnHostMsgResourceDestroyed)
  65     IPC_MESSAGE_UNHANDLED(handled = false)
  66   IPC_END_MESSAGE_MAP()
  67
  68   if (!handled) {
  69     for (size_t i = 0; i < instance_message_filters_.size(); i++) {
  70       if (instance_message_filters_[i]->OnInstanceMessageReceived(msg)) {
  71         handled = true;
  72         break;
  73       }
  74     }
  75   }
  76
  77   return handled;
  78 }
  79
  80 void PpapiHost::SendReply(const ReplyMessageContext& context,
  81                           const IPC::Message& msg) {
  82   TRACE_EVENT2("ppapi proxy", "PpapiHost::SendReply",
  83                "Class", IPC_MESSAGE_ID_CLASS(msg.type()),
  84                "Line", IPC_MESSAGE_ID_LINE(msg.type()));
  85   if (context.sync_reply_msg) {
  86     PpapiHostMsg_ResourceSyncCall::WriteReplyParams(context.sync_reply_msg,
  87                                                     context.params, msg);
  88     Send(context.sync_reply_msg);
  89   } else {
  90     if (context.routing_id != MSG_ROUTING_NONE) {
  91       Send(new PpapiHostMsg_InProcessResourceReply(context.routing_id,
  92                                                    context.params,
  93                                                    msg));
  94     } else {
  95       Send(new PpapiPluginMsg_ResourceReply(context.params, msg));
  96     }
  97   }
  98 }
  99
 100 void PpapiHost::SendUnsolicitedReply(PP_Resource resource,
 101                                      const IPC::Message& msg) {
 102   TRACE_EVENT2("ppapi proxy", "PpapiHost::SendUnsolicitedReply",
 103                "Class", IPC_MESSAGE_ID_CLASS(msg.type()),
 104                "Line", IPC_MESSAGE_ID_LINE(msg.type()));
 105   DCHECK(resource);  // If this fails, host is probably pending.
 106   proxy::ResourceMessageReplyParams params(resource, 0);
 107   Send(new PpapiPluginMsg_ResourceReply(params, msg));
 108 }
 109
 110 scoped_ptr<ResourceHost> PpapiHost::CreateResourceHost(
 111     const proxy::ResourceMessageCallParams& params,
 112     PP_Instance instance,
 113     const IPC::Message& nested_msg) {
 114   scoped_ptr<ResourceHost> resource_host;
 115   DCHECK(!host_factory_filters_.empty());  // Caller forgot to add a factory.
 116   for (size_t i = 0; i < host_factory_filters_.size(); i++) {
 117     resource_host = host_factory_filters_[i]->CreateResourceHost(
 118         this, params, instance, nested_msg).Pass();
 119     if (resource_host.get())
 120       break;
 121   }
 122   return resource_host.Pass();
 123 }
 124
 125 int PpapiHost::AddPendingResourceHost(scoped_ptr<ResourceHost> resource_host) {
 126   // The resource ID should not be assigned.
 127   if (!resource_host.get() || resource_host->pp_resource() != 0) {
 128     NOTREACHED();
 129     return 0;
 130   }
 131
 132   if (pending_resource_hosts_.size() + resources_.size()
 133       >= kMaxResourcesPerPlugin) {
 134     return 0;
 135   }
 136
 137   int pending_id = next_pending_resource_host_id_++;
 138   pending_resource_hosts_[pending_id] =
 139       linked_ptr<ResourceHost>(resource_host.release());
 140   return pending_id;
 141 }
 142
 143 void PpapiHost::AddHostFactoryFilter(scoped_ptr<HostFactory> filter) {
 144   host_factory_filters_.push_back(filter.release());
 145 }
 146
 147 void PpapiHost::AddInstanceMessageFilter(
 148     scoped_ptr<InstanceMessageFilter> filter) {
 149   instance_message_filters_.push_back(filter.release());
 150 }
 151
 152 void PpapiHost::OnHostMsgResourceCall(
 153     const proxy::ResourceMessageCallParams& params,
 154     const IPC::Message& nested_msg) {
 155   TRACE_EVENT2("ppapi proxy", "PpapiHost::OnHostMsgResourceCall",
 156                "Class", IPC_MESSAGE_ID_CLASS(nested_msg.type()),
 157                "Line", IPC_MESSAGE_ID_LINE(nested_msg.type()));
 158   HostMessageContext context(params);
 159   HandleResourceCall(params, nested_msg, &context);
 160 }
 161
 162 void PpapiHost::OnHostMsgInProcessResourceCall(
 163     int routing_id,
 164     const proxy::ResourceMessageCallParams& params,
 165     const IPC::Message& nested_msg) {
 166   TRACE_EVENT2("ppapi proxy", "PpapiHost::OnHostMsgInProcessResourceCall",
 167                "Class", IPC_MESSAGE_ID_CLASS(nested_msg.type()),
 168                "Line", IPC_MESSAGE_ID_LINE(nested_msg.type()));
 169   HostMessageContext context(routing_id, params);
 170   HandleResourceCall(params, nested_msg, &context);
 171 }
 172
 173 void PpapiHost::OnHostMsgResourceSyncCall(
 174     const proxy::ResourceMessageCallParams& params,
 175     const IPC::Message& nested_msg,
 176     IPC::Message* reply_msg) {
 177   TRACE_EVENT2("ppapi proxy", "PpapiHost::OnHostMsgResourceSyncCall",
 178                "Class", IPC_MESSAGE_ID_CLASS(nested_msg.type()),
 179                "Line", IPC_MESSAGE_ID_LINE(nested_msg.type()));
 180   // Sync messages should always have callback set because they always expect
 181   // a reply from the host.
 182   DCHECK(params.has_callback());
 183   // Stash the |reply_msg| in the context so that it can be used to reply
 184   // to the sync message.
 185   HostMessageContext context(params, reply_msg);
 186   HandleResourceCall(params, nested_msg, &context);
 187 }
 188
 189 void PpapiHost::HandleResourceCall(
 190     const proxy::ResourceMessageCallParams& params,
 191     const IPC::Message& nested_msg,
 192     HostMessageContext* context) {
 193   ResourceHost* resource_host = GetResourceHost(params.pp_resource());
 194   if (resource_host) {
 195     // CAUTION: Handling the message may cause the destruction of this object.
 196     resource_host->HandleMessage(nested_msg, context);
 197   } else {
 198     if (context->params.has_callback()) {
 199       ReplyMessageContext reply_context = context->MakeReplyMessageContext();
 200       reply_context.params.set_result(PP_ERROR_BADRESOURCE);
 201       SendReply(reply_context, context->reply_msg);
 202     }
 203   }
 204 }
 205
 206 void PpapiHost::OnHostMsgResourceCreated(
 207     const proxy::ResourceMessageCallParams& params,
 208     PP_Instance instance,
 209     const IPC::Message& nested_msg) {
 210   TRACE_EVENT2("ppapi proxy", "PpapiHost::OnHostMsgResourceCreated",
 211                "Class", IPC_MESSAGE_ID_CLASS(nested_msg.type()),
 212                "Line", IPC_MESSAGE_ID_LINE(nested_msg.type()));
 213
 214   if (pending_resource_hosts_.size() + resources_.size()
 215       >= kMaxResourcesPerPlugin) {
 216     return;
 217   }
 218
 219   // Run through all filters until one grabs this message.
 220   scoped_ptr<ResourceHost> resource_host = CreateResourceHost(params, instance,
 221                                                               nested_msg);
 222
 223   if (!resource_host.get()) {
 224     NOTREACHED();
 225     return;
 226   }
 227
 228   // Resource should have been assigned a nonzero PP_Resource.
 229   DCHECK(resource_host->pp_resource());
 230
 231   resources_[params.pp_resource()] =
 232       linked_ptr<ResourceHost>(resource_host.release());
 233 }
 234
 235 void PpapiHost::OnHostMsgAttachToPendingHost(PP_Resource pp_resource,
 236                                              int pending_host_id) {
 237   PendingHostResourceMap::iterator found =
 238       pending_resource_hosts_.find(pending_host_id);
 239   if (found == pending_resource_hosts_.end()) {
 240     // Plugin sent a bad ID.
 241     NOTREACHED();
 242     return;
 243   }
 244   found->second->SetPPResourceForPendingHost(pp_resource);
 245   resources_[pp_resource] = found->second;
 246   pending_resource_hosts_.erase(found);
 247 }
 248
 249 void PpapiHost::OnHostMsgResourceDestroyed(PP_Resource resource) {
 250   ResourceMap::iterator found = resources_.find(resource);
 251   if (found == resources_.end()) {
 252     NOTREACHED();
 253     return;
 254   }
 255   // Invoking the HostResource destructor might result in looking up the
 256   // PP_Resource in resources_. std::map is not well specified as to whether the
 257   // element will be there or not. Therefore, we delay destruction of the
 258   // HostResource until after we've made sure the map no longer contains
 259   // |resource|.
 260   linked_ptr<ResourceHost> delete_at_end_of_scope(found->second);
 261   resources_.erase(found);
 262 }
 263
 264 ResourceHost* PpapiHost::GetResourceHost(PP_Resource resource) const {
 265   ResourceMap::const_iterator found = resources_.find(resource);
 266   return found == resources_.end() ? NULL : found->second.get();
 267 }
 268
 269 }  // namespace host
 270 }  // namespace ppapi