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_DELAY_REPLY(PpapiHostMsg_ResourceSyncCall,
  56                                     OnHostMsgResourceSyncCall)
  57     IPC_MESSAGE_HANDLER(PpapiHostMsg_ResourceCreated,
  58                         OnHostMsgResourceCreated)
  59     IPC_MESSAGE_HANDLER(PpapiHostMsg_AttachToPendingHost,
  60                         OnHostMsgAttachToPendingHost)
  61     IPC_MESSAGE_HANDLER(PpapiHostMsg_ResourceDestroyed,
  62                         OnHostMsgResourceDestroyed)
  63     IPC_MESSAGE_UNHANDLED(handled = false)
  64   IPC_END_MESSAGE_MAP()
  65
  66   if (!handled) {
  67     for (size_t i = 0; i < instance_message_filters_.size(); i++) {
  68       if (instance_message_filters_[i]->OnInstanceMessageReceived(msg)) {
  69         handled = true;
  70         break;
  71       }
  72     }
  73   }
  74
  75   return handled;
  76 }
  77
  78 void PpapiHost::SendReply(const ReplyMessageContext& context,
  79                           const IPC::Message& msg) {
  80   TRACE_EVENT2("ppapi proxy", "PpapiHost::SendReply",
  81                "Class", IPC_MESSAGE_ID_CLASS(msg.type()),
  82                "Line", IPC_MESSAGE_ID_LINE(msg.type()));
  83   if (context.sync_reply_msg) {
  84     PpapiHostMsg_ResourceSyncCall::WriteReplyParams(context.sync_reply_msg,
  85                                                     context.params, msg);
  86     Send(context.sync_reply_msg);
  87   } else {
  88     Send(new PpapiPluginMsg_ResourceReply(context.params, msg));
  89   }
  90 }
  91
  92 void PpapiHost::SendUnsolicitedReply(PP_Resource resource,
  93                                      const IPC::Message& msg) {
  94   TRACE_EVENT2("ppapi proxy", "PpapiHost::SendUnsolicitedReply",
  95                "Class", IPC_MESSAGE_ID_CLASS(msg.type()),
  96                "Line", IPC_MESSAGE_ID_LINE(msg.type()));
  97   DCHECK(resource);  // If this fails, host is probably pending.
  98   proxy::ResourceMessageReplyParams params(resource, 0);
  99   Send(new PpapiPluginMsg_ResourceReply(params, msg));
 100 }
 101
 102 int PpapiHost::AddPendingResourceHost(scoped_ptr<ResourceHost> resource_host) {
 103   // The resource ID should not be assigned.
 104   DCHECK(resource_host->pp_resource() == 0);
 105
 106   int pending_id = next_pending_resource_host_id_++;
 107   pending_resource_hosts_[pending_id] =
 108       linked_ptr<ResourceHost>(resource_host.release());
 109   return pending_id;
 110 }
 111
 112 void PpapiHost::AddHostFactoryFilter(scoped_ptr<HostFactory> filter) {
 113   host_factory_filters_.push_back(filter.release());
 114 }
 115
 116 void PpapiHost::AddInstanceMessageFilter(
 117     scoped_ptr<InstanceMessageFilter> filter) {
 118   instance_message_filters_.push_back(filter.release());
 119 }
 120
 121 void PpapiHost::OnHostMsgResourceCall(
 122     const proxy::ResourceMessageCallParams& params,
 123     const IPC::Message& nested_msg) {
 124   TRACE_EVENT2("ppapi proxy", "PpapiHost::OnHostMsgResourceCall",
 125                "Class", IPC_MESSAGE_ID_CLASS(nested_msg.type()),
 126                "Line", IPC_MESSAGE_ID_LINE(nested_msg.type()));
 127   HostMessageContext context(params);
 128   HandleResourceCall(params, nested_msg, &context);
 129 }
 130
 131 void PpapiHost::OnHostMsgResourceSyncCall(
 132     const proxy::ResourceMessageCallParams& params,
 133     const IPC::Message& nested_msg,
 134     IPC::Message* reply_msg) {
 135   TRACE_EVENT2("ppapi proxy", "PpapiHost::OnHostMsgResourceSyncCall",
 136                "Class", IPC_MESSAGE_ID_CLASS(nested_msg.type()),
 137                "Line", IPC_MESSAGE_ID_LINE(nested_msg.type()));
 138   // Sync messages should always have callback set because they always expect
 139   // a reply from the host.
 140   DCHECK(params.has_callback());
 141   // Stash the |reply_msg| in the context so that it can be used to reply
 142   // to the sync message.
 143   HostMessageContext context(params, reply_msg);
 144   HandleResourceCall(params, nested_msg, &context);
 145 }
 146
 147 void PpapiHost::HandleResourceCall(
 148     const proxy::ResourceMessageCallParams& params,
 149     const IPC::Message& nested_msg,
 150     HostMessageContext* context) {
 151   ResourceHost* resource_host = GetResourceHost(params.pp_resource());
 152   if (resource_host) {
 153     // CAUTION: Handling the message may cause the destruction of this object.
 154     resource_host->HandleMessage(nested_msg, context);
 155   } else {
 156     if (context->params.has_callback()) {
 157       ReplyMessageContext reply_context = context->MakeReplyMessageContext();
 158       reply_context.params.set_result(PP_ERROR_BADRESOURCE);
 159       SendReply(reply_context, context->reply_msg);
 160     }
 161   }
 162 }
 163
 164 void PpapiHost::OnHostMsgResourceCreated(
 165     const proxy::ResourceMessageCallParams& params,
 166     PP_Instance instance,
 167     const IPC::Message& nested_msg) {
 168   TRACE_EVENT2("ppapi proxy", "PpapiHost::OnHostMsgResourceCreated",
 169                "Class", IPC_MESSAGE_ID_CLASS(nested_msg.type()),
 170                "Line", IPC_MESSAGE_ID_LINE(nested_msg.type()));
 171   if (resources_.size() >= kMaxResourcesPerPlugin)
 172     return;
 173
 174   // Run through all filters until one grabs this message.
 175   scoped_ptr<ResourceHost> resource_host;
 176   DCHECK(!host_factory_filters_.empty());  // Caller forgot to add a factory.
 177   for (size_t i = 0; i < host_factory_filters_.size(); i++) {
 178     resource_host = host_factory_filters_[i]->CreateResourceHost(
 179         this, params, instance, nested_msg).Pass();
 180     if (resource_host.get())
 181       break;
 182   }
 183   if (!resource_host.get()) {
 184     NOTREACHED();
 185     return;
 186   }
 187
 188   // Resource should have been assigned a nonzero PP_Resource.
 189   DCHECK(resource_host->pp_resource());
 190
 191   resources_[params.pp_resource()] =
 192       linked_ptr<ResourceHost>(resource_host.release());
 193 }
 194
 195 void PpapiHost::OnHostMsgAttachToPendingHost(PP_Resource pp_resource,
 196                                              int pending_host_id) {
 197   PendingHostResourceMap::iterator found =
 198       pending_resource_hosts_.find(pending_host_id);
 199   if (found == pending_resource_hosts_.end()) {
 200     // Plugin sent a bad ID.
 201     NOTREACHED();
 202     return;
 203   }
 204   found->second->SetPPResourceForPendingHost(pp_resource);
 205   resources_[pp_resource] = found->second;
 206   pending_resource_hosts_.erase(found);
 207 }
 208
 209 void PpapiHost::OnHostMsgResourceDestroyed(PP_Resource resource) {
 210   ResourceMap::iterator found = resources_.find(resource);
 211   if (found == resources_.end()) {
 212     NOTREACHED();
 213     return;
 214   }
 215   // Invoking the HostResource destructor might result in looking up the
 216   // PP_Resource in resources_. std::map is not well specified as to whether the
 217   // element will be there or not. Therefore, we delay destruction of the
 218   // HostResource until after we've made sure the map no longer contains
 219   // |resource|.
 220   linked_ptr<ResourceHost> delete_at_end_of_scope(found->second);
 221   resources_.erase(found);
 222 }
 223
 224 ResourceHost* PpapiHost::GetResourceHost(PP_Resource resource) const {
 225   ResourceMap::const_iterator found = resources_.find(resource);
 226   return found == resources_.end() ? NULL : found->second.get();
 227 }
 228
 229 }  // namespace host
 230 }  // namespace ppapi