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/proxy/serialized_handle.h"
  16 #include "ppapi/shared_impl/host_resource.h"
  17
  18 namespace ppapi {
  19 namespace host {
  20
  21 using proxy::SerializedHandle;
  22
  23 namespace {
  24
  25 // Put a cap on the maximum number of resources so we don't explode if the
  26 // renderer starts spamming us.
  27 const size_t kMaxResourcesPerPlugin = 1 << 14;
  28
  29 }  // namespace
  30
  31 PpapiHost::PpapiHost(IPC::Sender* sender,
  32                      const PpapiPermissions& perms)
  33     : sender_(sender),
  34       permissions_(perms),
  35       next_pending_resource_host_id_(1) {
  36 }
  37
  38 PpapiHost::~PpapiHost() {
  39   // Delete these explicitly before destruction since then the host is still
  40   // technically alive in case one of the filters accesses us from the
  41   // destructor.
  42   instance_message_filters_.clear();
  43
  44   // The resources may also want to use us in their destructors.
  45   resources_.clear();
  46   pending_resource_hosts_.clear();
  47 }
  48
  49 bool PpapiHost::Send(IPC::Message* msg) {
  50   return sender_->Send(msg);
  51 }
  52
  53 bool PpapiHost::OnMessageReceived(const IPC::Message& msg) {
  54   bool handled = true;
  55   IPC_BEGIN_MESSAGE_MAP(PpapiHost, msg)
  56     IPC_MESSAGE_HANDLER(PpapiHostMsg_ResourceCall,
  57                         OnHostMsgResourceCall)
  58     IPC_MESSAGE_HANDLER(PpapiHostMsg_InProcessResourceCall,
  59                         OnHostMsgInProcessResourceCall)
  60     IPC_MESSAGE_HANDLER_DELAY_REPLY(PpapiHostMsg_ResourceSyncCall,
  61                                     OnHostMsgResourceSyncCall)
  62     IPC_MESSAGE_HANDLER(PpapiHostMsg_ResourceCreated,
  63                         OnHostMsgResourceCreated)
  64     IPC_MESSAGE_HANDLER(PpapiHostMsg_AttachToPendingHost,
  65                         OnHostMsgAttachToPendingHost)
  66     IPC_MESSAGE_HANDLER(PpapiHostMsg_ResourceDestroyed,
  67                         OnHostMsgResourceDestroyed)
  68     IPC_MESSAGE_UNHANDLED(handled = false)
  69   IPC_END_MESSAGE_MAP()
  70
  71   if (!handled) {
  72     for (size_t i = 0; i < instance_message_filters_.size(); i++) {
  73       if (instance_message_filters_[i]->OnInstanceMessageReceived(msg)) {
  74         handled = true;
  75         break;
  76       }
  77     }
  78   }
  79
  80   return handled;
  81 }
  82
  83 void PpapiHost::SendReply(const ReplyMessageContext& context,
  84                           const IPC::Message& msg) {
  85   TRACE_EVENT2("ppapi proxy", "PpapiHost::SendReply",
  86                "Class", IPC_MESSAGE_ID_CLASS(msg.type()),
  87                "Line", IPC_MESSAGE_ID_LINE(msg.type()));
  88   if (context.sync_reply_msg) {
  89     PpapiHostMsg_ResourceSyncCall::WriteReplyParams(context.sync_reply_msg,
  90                                                     context.params, msg);
  91     Send(context.sync_reply_msg);
  92   } else {
  93     if (context.routing_id != MSG_ROUTING_NONE) {
  94       Send(new PpapiHostMsg_InProcessResourceReply(context.routing_id,
  95                                                    context.params,
  96                                                    msg));
  97     } else {
  98       Send(new PpapiPluginMsg_ResourceReply(context.params, msg));
  99     }
 100   }
 101 }
 102
 103 void PpapiHost::SendUnsolicitedReply(PP_Resource resource,
 104                                      const IPC::Message& msg) {
 105   SendUnsolicitedReplyWithHandles(
 106       resource, msg, std::vector<SerializedHandle>());
 107 }
 108
 109 void PpapiHost::SendUnsolicitedReplyWithHandles(
 110     PP_Resource resource,
 111     const IPC::Message& msg,
 112     const std::vector<SerializedHandle>& handles) {
 113   TRACE_EVENT2("ppapi proxy", "PpapiHost::SendUnsolicitedReplyWithHandles",
 114                "Class", IPC_MESSAGE_ID_CLASS(msg.type()),
 115                "Line", IPC_MESSAGE_ID_LINE(msg.type()));
 116   DCHECK(resource);  // If this fails, host is probably pending.
 117   proxy::ResourceMessageReplyParams params(resource, 0);
 118   for (std::vector<SerializedHandle>::const_iterator it = handles.begin();
 119       it != handles.end(); ++it) {
 120     params.AppendHandle(*it);
 121   }
 122   Send(new PpapiPluginMsg_ResourceReply(params, msg));
 123 }
 124
 125 scoped_ptr<ResourceHost> PpapiHost::CreateResourceHost(
 126     PP_Resource resource,
 127     PP_Instance instance,
 128     const IPC::Message& nested_msg) {
 129   scoped_ptr<ResourceHost> resource_host;
 130   DCHECK(!host_factory_filters_.empty());  // Caller forgot to add a factory.
 131   for (size_t i = 0; i < host_factory_filters_.size(); i++) {
 132     resource_host =
 133         host_factory_filters_[i]
 134             ->CreateResourceHost(this, resource, instance, nested_msg)
 135             .Pass();
 136     if (resource_host.get())
 137       break;
 138   }
 139   return resource_host.Pass();
 140 }
 141
 142 int PpapiHost::AddPendingResourceHost(scoped_ptr<ResourceHost> resource_host) {
 143   // The resource ID should not be assigned.
 144   if (!resource_host.get() || resource_host->pp_resource() != 0) {
 145     NOTREACHED();
 146     return 0;
 147   }
 148
 149   if (pending_resource_hosts_.size() + resources_.size()
 150       >= kMaxResourcesPerPlugin) {
 151     return 0;
 152   }
 153
 154   int pending_id = next_pending_resource_host_id_++;
 155   pending_resource_hosts_[pending_id] =
 156       linked_ptr<ResourceHost>(resource_host.release());
 157   return pending_id;
 158 }
 159
 160 void PpapiHost::AddHostFactoryFilter(scoped_ptr<HostFactory> filter) {
 161   host_factory_filters_.push_back(filter.release());
 162 }
 163
 164 void PpapiHost::AddInstanceMessageFilter(
 165     scoped_ptr<InstanceMessageFilter> filter) {
 166   instance_message_filters_.push_back(filter.release());
 167 }
 168
 169 void PpapiHost::OnHostMsgResourceCall(
 170     const proxy::ResourceMessageCallParams& params,
 171     const IPC::Message& nested_msg) {
 172   TRACE_EVENT2("ppapi proxy", "PpapiHost::OnHostMsgResourceCall",
 173                "Class", IPC_MESSAGE_ID_CLASS(nested_msg.type()),
 174                "Line", IPC_MESSAGE_ID_LINE(nested_msg.type()));
 175   HostMessageContext context(params);
 176   HandleResourceCall(params, nested_msg, &context);
 177 }
 178
 179 void PpapiHost::OnHostMsgInProcessResourceCall(
 180     int routing_id,
 181     const proxy::ResourceMessageCallParams& params,
 182     const IPC::Message& nested_msg) {
 183   TRACE_EVENT2("ppapi proxy", "PpapiHost::OnHostMsgInProcessResourceCall",
 184                "Class", IPC_MESSAGE_ID_CLASS(nested_msg.type()),
 185                "Line", IPC_MESSAGE_ID_LINE(nested_msg.type()));
 186   HostMessageContext context(routing_id, params);
 187   HandleResourceCall(params, nested_msg, &context);
 188 }
 189
 190 void PpapiHost::OnHostMsgResourceSyncCall(
 191     const proxy::ResourceMessageCallParams& params,
 192     const IPC::Message& nested_msg,
 193     IPC::Message* reply_msg) {
 194   TRACE_EVENT2("ppapi proxy", "PpapiHost::OnHostMsgResourceSyncCall",
 195                "Class", IPC_MESSAGE_ID_CLASS(nested_msg.type()),
 196                "Line", IPC_MESSAGE_ID_LINE(nested_msg.type()));
 197   // Sync messages should always have callback set because they always expect
 198   // a reply from the host.
 199   DCHECK(params.has_callback());
 200   // Stash the |reply_msg| in the context so that it can be used to reply
 201   // to the sync message.
 202   HostMessageContext context(params, reply_msg);
 203   HandleResourceCall(params, nested_msg, &context);
 204 }
 205
 206 void PpapiHost::HandleResourceCall(
 207     const proxy::ResourceMessageCallParams& params,
 208     const IPC::Message& nested_msg,
 209     HostMessageContext* context) {
 210   ResourceHost* resource_host = GetResourceHost(params.pp_resource());
 211   if (resource_host) {
 212     // CAUTION: Handling the message may cause the destruction of this object.
 213     resource_host->HandleMessage(nested_msg, context);
 214   } else {
 215     if (context->params.has_callback()) {
 216       ReplyMessageContext reply_context = context->MakeReplyMessageContext();
 217       reply_context.params.set_result(PP_ERROR_BADRESOURCE);
 218       SendReply(reply_context, context->reply_msg);
 219     }
 220   }
 221 }
 222
 223 void PpapiHost::OnHostMsgResourceCreated(
 224     const proxy::ResourceMessageCallParams& params,
 225     PP_Instance instance,
 226     const IPC::Message& nested_msg) {
 227   TRACE_EVENT2("ppapi proxy", "PpapiHost::OnHostMsgResourceCreated",
 228                "Class", IPC_MESSAGE_ID_CLASS(nested_msg.type()),
 229                "Line", IPC_MESSAGE_ID_LINE(nested_msg.type()));
 230
 231   if (pending_resource_hosts_.size() + resources_.size()
 232       >= kMaxResourcesPerPlugin) {
 233     return;
 234   }
 235
 236   // Run through all filters until one grabs this message.
 237   scoped_ptr<ResourceHost> resource_host =
 238       CreateResourceHost(params.pp_resource(), instance, nested_msg);
 239
 240   if (!resource_host.get()) {
 241     NOTREACHED();
 242     return;
 243   }
 244
 245   // Resource should have been assigned a nonzero PP_Resource.
 246   DCHECK(resource_host->pp_resource());
 247
 248   resources_[params.pp_resource()] =
 249       linked_ptr<ResourceHost>(resource_host.release());
 250 }
 251
 252 void PpapiHost::OnHostMsgAttachToPendingHost(PP_Resource pp_resource,
 253                                              int pending_host_id) {
 254   PendingHostResourceMap::iterator found =
 255       pending_resource_hosts_.find(pending_host_id);
 256   if (found == pending_resource_hosts_.end()) {
 257     // Plugin sent a bad ID.
 258     NOTREACHED();
 259     return;
 260   }
 261   found->second->SetPPResourceForPendingHost(pp_resource);
 262   resources_[pp_resource] = found->second;
 263   pending_resource_hosts_.erase(found);
 264 }
 265
 266 void PpapiHost::OnHostMsgResourceDestroyed(PP_Resource resource) {
 267   ResourceMap::iterator found = resources_.find(resource);
 268   if (found == resources_.end()) {
 269     NOTREACHED();
 270     return;
 271   }
 272   // Invoking the HostResource destructor might result in looking up the
 273   // PP_Resource in resources_. std::map is not well specified as to whether the
 274   // element will be there or not. Therefore, we delay destruction of the
 275   // HostResource until after we've made sure the map no longer contains
 276   // |resource|.
 277   linked_ptr<ResourceHost> delete_at_end_of_scope(found->second);
 278   resources_.erase(found);
 279 }
 280
 281 ResourceHost* PpapiHost::GetResourceHost(PP_Resource resource) const {
 282   ResourceMap::const_iterator found = resources_.find(resource);
 283   return found == resources_.end() ? NULL : found->second.get();
 284 }
 285
 286 }  // namespace host
 287 }  // namespace ppapi