src/ppapi/proxy/serialized_var.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/serialized_var.h"
   6
   7 #include "base/logging.h"
   8 #include "ipc/ipc_message_utils.h"
   9 #include "ppapi/c/pp_instance.h"
  10 #include "ppapi/proxy/dispatcher.h"
  11 #include "ppapi/proxy/interface_proxy.h"
  12 #include "ppapi/proxy/ppapi_param_traits.h"
  13 #include "ppapi/proxy/ppb_buffer_proxy.h"
  14 #include "ppapi/shared_impl/ppapi_globals.h"
  15 #include "ppapi/shared_impl/var.h"
  16 #include "ppapi/thunk/enter.h"
  17
  18 namespace ppapi {
  19 namespace proxy {
  20
  21 namespace {
  22 void DefaultHandleWriter(IPC::Message* m, const SerializedHandle& handle) {
  23   IPC::ParamTraits<SerializedHandle>::Write(m, handle);
  24 }
  25 }  // namespace
  26
  27 // SerializedVar::Inner --------------------------------------------------------
  28
  29 SerializedVar::Inner::Inner()
  30     : serialization_rules_(NULL),
  31       var_(PP_MakeUndefined()),
  32       instance_(0),
  33       cleanup_mode_(CLEANUP_NONE),
  34       is_valid_var_(true) {
  35 #ifndef NDEBUG
  36   has_been_serialized_ = false;
  37   has_been_deserialized_ = false;
  38 #endif
  39 }
  40
  41 SerializedVar::Inner::Inner(VarSerializationRules* serialization_rules)
  42     : serialization_rules_(serialization_rules),
  43       var_(PP_MakeUndefined()),
  44       instance_(0),
  45       cleanup_mode_(CLEANUP_NONE) {
  46 #ifndef NDEBUG
  47   has_been_serialized_ = false;
  48   has_been_deserialized_ = false;
  49 #endif
  50 }
  51
  52 SerializedVar::Inner::~Inner() {
  53   switch (cleanup_mode_) {
  54     case END_SEND_PASS_REF:
  55       serialization_rules_->EndSendPassRef(var_);
  56       break;
  57     case END_RECEIVE_CALLER_OWNED:
  58       serialization_rules_->EndReceiveCallerOwned(var_);
  59       break;
  60     default:
  61       break;
  62   }
  63 }
  64
  65 PP_Var SerializedVar::Inner::GetVar() {
  66   DCHECK(serialization_rules_.get());
  67
  68 #if defined(NACL_WIN64)
  69   NOTREACHED();
  70   return PP_MakeUndefined();
  71 #endif
  72
  73   if (raw_var_data_.get()) {
  74     var_ = raw_var_data_->CreatePPVar(instance_);
  75     raw_var_data_.reset(NULL);
  76   }
  77
  78   return var_;
  79 }
  80
  81 void SerializedVar::Inner::SetVar(PP_Var var) {
  82   // Sanity check, when updating the var we should have received a
  83   // serialization rules pointer already.
  84   DCHECK(serialization_rules_.get());
  85   var_ = var;
  86   raw_var_data_.reset(NULL);
  87 }
  88
  89 void SerializedVar::Inner::SetInstance(PP_Instance instance) {
  90   instance_ = instance;
  91 }
  92
  93 void SerializedVar::Inner::ForceSetVarValueForTest(PP_Var value) {
  94   var_ = value;
  95   raw_var_data_.reset(NULL);
  96 }
  97
  98 void SerializedVar::Inner::WriteToMessage(IPC::Message* m) const {
  99   // When writing to the IPC messages, a serialization rules handler should
 100   // always have been set.
 101   //
 102   // When sending a message, it should be difficult to trigger this if you're
 103   // using the SerializedVarSendInput class and giving a non-NULL dispatcher.
 104   // Make sure you're using the proper "Send" helper class.
 105   //
 106   // It should be more common to see this when handling an incoming message
 107   // that returns a var. This means the message handler didn't write to the
 108   // output parameter, or possibly you used the wrong helper class
 109   // (normally SerializedVarReturnValue).
 110   DCHECK(serialization_rules_.get());
 111
 112 #ifndef NDEBUG
 113   // We should only be serializing something once.
 114   DCHECK(!has_been_serialized_);
 115   has_been_serialized_ = true;
 116 #endif
 117   scoped_ptr<RawVarDataGraph> data = RawVarDataGraph::Create(var_, instance_);
 118   if (data) {
 119     m->WriteBool(true);  // Success.
 120     data->Write(m, base::Bind(&DefaultHandleWriter));
 121   } else {
 122     m->WriteBool(false);  // Failure.
 123   }
 124 }
 125
 126 void SerializedVar::Inner::WriteDataToMessage(
 127     IPC::Message* m,
 128     const HandleWriter& handle_writer) const {
 129   if (raw_var_data_) {
 130     m->WriteBool(true);  // Success.
 131     raw_var_data_->Write(m, handle_writer);
 132   } else {
 133     m->WriteBool(false);  // Failure.
 134   }
 135 }
 136
 137 bool SerializedVar::Inner::ReadFromMessage(const IPC::Message* m,
 138                                            PickleIterator* iter) {
 139 #ifndef NDEBUG
 140   // We should only deserialize something once or will end up with leaked
 141   // references.
 142   //
 143   // One place this has happened in the past is using
 144   // std::vector<SerializedVar>.resize(). If you're doing this manually instead
 145   // of using the helper classes for handling in/out vectors of vars, be
 146   // sure you use the same pattern as the SerializedVarVector classes.
 147   DCHECK(!has_been_deserialized_);
 148   has_been_deserialized_ = true;
 149 #endif
 150   // When reading, the dispatcher should be set when we get a Deserialize
 151   // call (which will supply a dispatcher).
 152   if (!m->ReadBool(iter, &is_valid_var_))
 153       return false;
 154   if (is_valid_var_) {
 155     raw_var_data_ = RawVarDataGraph::Read(m, iter);
 156     if (!raw_var_data_)
 157       return false;
 158   }
 159
 160   return true;
 161 }
 162
 163 void SerializedVar::Inner::SetCleanupModeToEndSendPassRef() {
 164   cleanup_mode_ = END_SEND_PASS_REF;
 165 }
 166
 167 void SerializedVar::Inner::SetCleanupModeToEndReceiveCallerOwned() {
 168   cleanup_mode_ = END_RECEIVE_CALLER_OWNED;
 169 }
 170
 171 // SerializedVar ---------------------------------------------------------------
 172
 173 SerializedVar::SerializedVar() : inner_(new Inner) {
 174 }
 175
 176 SerializedVar::SerializedVar(VarSerializationRules* serialization_rules)
 177     : inner_(new Inner(serialization_rules)) {
 178 }
 179
 180 SerializedVar::~SerializedVar() {
 181 }
 182
 183 // SerializedVarSendInput ------------------------------------------------------
 184
 185 SerializedVarSendInput::SerializedVarSendInput(Dispatcher* dispatcher,
 186                                                const PP_Var& var)
 187     : SerializedVar(dispatcher->serialization_rules()) {
 188   inner_->SetVar(dispatcher->serialization_rules()->SendCallerOwned(var));
 189 }
 190
 191 // static
 192 void SerializedVarSendInput::ConvertVector(Dispatcher* dispatcher,
 193                                            const PP_Var* input,
 194                                            size_t input_count,
 195                                            std::vector<SerializedVar>* output) {
 196   output->reserve(input_count);
 197   for (size_t i = 0; i < input_count; i++)
 198     output->push_back(SerializedVarSendInput(dispatcher, input[i]));
 199 }
 200
 201 // SerializedVarSendInputShmem -------------------------------------------------
 202
 203 SerializedVarSendInputShmem::SerializedVarSendInputShmem(
 204     Dispatcher* dispatcher,
 205     const PP_Var& var,
 206     const PP_Instance& instance)
 207     : SerializedVar(dispatcher->serialization_rules()) {
 208   inner_->SetVar(dispatcher->serialization_rules()->SendCallerOwned(var));
 209   inner_->SetInstance(instance);
 210 }
 211
 212 // ReceiveSerializedVarReturnValue ---------------------------------------------
 213
 214 ReceiveSerializedVarReturnValue::ReceiveSerializedVarReturnValue() {
 215 }
 216
 217 ReceiveSerializedVarReturnValue::ReceiveSerializedVarReturnValue(
 218     const SerializedVar& serialized)
 219     : SerializedVar(serialized) {
 220 }
 221
 222 PP_Var ReceiveSerializedVarReturnValue::Return(Dispatcher* dispatcher) {
 223   inner_->set_serialization_rules(dispatcher->serialization_rules());
 224   inner_->SetVar(inner_->serialization_rules()->ReceivePassRef(
 225       inner_->GetVar()));
 226   return inner_->GetVar();
 227 }
 228
 229 // ReceiveSerializedException --------------------------------------------------
 230
 231 ReceiveSerializedException::ReceiveSerializedException(Dispatcher* dispatcher,
 232                                                        PP_Var* exception)
 233     : SerializedVar(dispatcher->serialization_rules()),
 234       exception_(exception) {
 235 }
 236
 237 ReceiveSerializedException::~ReceiveSerializedException() {
 238   if (exception_) {
 239     // When an output exception is specified, it will take ownership of the
 240     // reference.
 241     inner_->SetVar(
 242         inner_->serialization_rules()->ReceivePassRef(inner_->GetVar()));
 243     *exception_ = inner_->GetVar();
 244   } else {
 245     // When no output exception is specified, the browser thinks we have a ref
 246     // to an object that we don't want (this will happen only in the plugin
 247     // since the browser will always specify an out exception for the plugin to
 248     // write into).
 249     //
 250     // Strings don't need this handling since we can just avoid creating a
 251     // Var from the std::string in the first place.
 252     if (inner_->GetVar().type == PP_VARTYPE_OBJECT)
 253       inner_->serialization_rules()->ReleaseObjectRef(inner_->GetVar());
 254   }
 255 }
 256
 257 bool ReceiveSerializedException::IsThrown() const {
 258   return exception_ && exception_->type != PP_VARTYPE_UNDEFINED;
 259 }
 260
 261 // ReceiveSerializedVarVectorOutParam ------------------------------------------
 262
 263 ReceiveSerializedVarVectorOutParam::ReceiveSerializedVarVectorOutParam(
 264     Dispatcher* dispatcher,
 265     uint32_t* output_count,
 266     PP_Var** output)
 267     : dispatcher_(dispatcher),
 268       output_count_(output_count),
 269       output_(output) {
 270 }
 271
 272 ReceiveSerializedVarVectorOutParam::~ReceiveSerializedVarVectorOutParam() {
 273   *output_count_ = static_cast<uint32_t>(vector_.size());
 274   if (!vector_.size()) {
 275     *output_ = NULL;
 276     return;
 277   }
 278
 279   *output_ = static_cast<PP_Var*>(malloc(vector_.size() * sizeof(PP_Var)));
 280   for (size_t i = 0; i < vector_.size(); i++) {
 281     // Here we just mimic what happens when returning a value.
 282     ReceiveSerializedVarReturnValue converted;
 283     SerializedVar* serialized = &converted;
 284     *serialized = vector_[i];
 285     (*output_)[i] = converted.Return(dispatcher_);
 286   }
 287 }
 288
 289 std::vector<SerializedVar>* ReceiveSerializedVarVectorOutParam::OutParam() {
 290   return &vector_;
 291 }
 292
 293 // SerializedVarReceiveInput ---------------------------------------------------
 294
 295 SerializedVarReceiveInput::SerializedVarReceiveInput(
 296     const SerializedVar& serialized)
 297     : serialized_(serialized) {
 298 }
 299
 300 SerializedVarReceiveInput::~SerializedVarReceiveInput() {
 301 }
 302
 303 PP_Var SerializedVarReceiveInput::Get(Dispatcher* dispatcher) {
 304   serialized_.inner_->set_serialization_rules(
 305       dispatcher->serialization_rules());
 306
 307   // Ensure that when the serialized var goes out of scope it cleans up the
 308   // stuff we're making in BeginReceiveCallerOwned.
 309   serialized_.inner_->SetCleanupModeToEndReceiveCallerOwned();
 310
 311   serialized_.inner_->SetVar(
 312       serialized_.inner_->serialization_rules()->BeginReceiveCallerOwned(
 313           serialized_.inner_->GetVar()));
 314   return serialized_.inner_->GetVar();
 315 }
 316
 317
 318 PP_Var SerializedVarReceiveInput::GetForInstance(Dispatcher* dispatcher,
 319                                                  PP_Instance instance) {
 320   serialized_.inner_->SetInstance(instance);
 321   return Get(dispatcher);
 322 }
 323
 324 // SerializedVarVectorReceiveInput ---------------------------------------------
 325
 326 SerializedVarVectorReceiveInput::SerializedVarVectorReceiveInput(
 327     const std::vector<SerializedVar>& serialized)
 328     : serialized_(serialized) {
 329 }
 330
 331 SerializedVarVectorReceiveInput::~SerializedVarVectorReceiveInput() {
 332   for (size_t i = 0; i < deserialized_.size(); i++) {
 333     serialized_[i].inner_->serialization_rules()->EndReceiveCallerOwned(
 334         deserialized_[i]);
 335   }
 336 }
 337
 338 PP_Var* SerializedVarVectorReceiveInput::Get(Dispatcher* dispatcher,
 339                                              uint32_t* array_size) {
 340   deserialized_.resize(serialized_.size());
 341   for (size_t i = 0; i < serialized_.size(); i++) {
 342     // The vectors must be able to clean themselves up after this call is
 343     // torn down.
 344     serialized_[i].inner_->set_serialization_rules(
 345         dispatcher->serialization_rules());
 346
 347     serialized_[i].inner_->SetVar(
 348         serialized_[i].inner_->serialization_rules()->BeginReceiveCallerOwned(
 349             serialized_[i].inner_->GetVar()));
 350     deserialized_[i] = serialized_[i].inner_->GetVar();
 351   }
 352
 353   *array_size = static_cast<uint32_t>(serialized_.size());
 354   return deserialized_.empty() ? NULL : &deserialized_[0];
 355 }
 356
 357 // SerializedVarReturnValue ----------------------------------------------------
 358
 359 SerializedVarReturnValue::SerializedVarReturnValue(SerializedVar* serialized)
 360     : serialized_(serialized) {
 361 }
 362
 363 void SerializedVarReturnValue::Return(Dispatcher* dispatcher,
 364                                       const PP_Var& var) {
 365   serialized_->inner_->set_serialization_rules(
 366       dispatcher->serialization_rules());
 367
 368   // Var must clean up after our BeginSendPassRef call.
 369   serialized_->inner_->SetCleanupModeToEndSendPassRef();
 370
 371   serialized_->inner_->SetVar(
 372       dispatcher->serialization_rules()->BeginSendPassRef(var));
 373 }
 374
 375 // static
 376 SerializedVar SerializedVarReturnValue::Convert(Dispatcher* dispatcher,
 377                                                 const PP_Var& var) {
 378   // Mimic what happens in the normal case.
 379   SerializedVar result;
 380   SerializedVarReturnValue retvalue(&result);
 381   retvalue.Return(dispatcher, var);
 382   return result;
 383 }
 384
 385 // SerializedVarOutParam -------------------------------------------------------
 386
 387 SerializedVarOutParam::SerializedVarOutParam(SerializedVar* serialized)
 388     : serialized_(serialized),
 389       writable_var_(PP_MakeUndefined()),
 390       dispatcher_(NULL) {
 391 }
 392
 393 SerializedVarOutParam::~SerializedVarOutParam() {
 394   if (serialized_->inner_->serialization_rules()) {
 395     // When unset, OutParam wasn't called. We'll just leave the var untouched
 396     // in that case.
 397     serialized_->inner_->SetVar(
 398         serialized_->inner_->serialization_rules()->BeginSendPassRef(
 399             writable_var_));
 400
 401     // Normally the current object will be created on the stack to wrap a
 402     // SerializedVar and won't have a scope around the actual IPC send. So we
 403     // need to tell the SerializedVar to do the begin/end send pass ref calls.
 404     serialized_->inner_->SetCleanupModeToEndSendPassRef();
 405   }
 406 }
 407
 408 PP_Var* SerializedVarOutParam::OutParam(Dispatcher* dispatcher) {
 409   dispatcher_ = dispatcher;
 410   serialized_->inner_->set_serialization_rules(
 411       dispatcher->serialization_rules());
 412   return &writable_var_;
 413 }
 414
 415 // SerializedVarVectorOutParam -------------------------------------------------
 416
 417 SerializedVarVectorOutParam::SerializedVarVectorOutParam(
 418     std::vector<SerializedVar>* serialized)
 419     : dispatcher_(NULL),
 420       serialized_(serialized),
 421       count_(0),
 422       array_(NULL) {
 423 }
 424
 425 SerializedVarVectorOutParam::~SerializedVarVectorOutParam() {
 426   DCHECK(dispatcher_);
 427
 428   // Convert the array written by the pepper code to the serialized structure.
 429   // Note we can't use resize here, we have to allocate a new SerializedVar
 430   // for each serialized item. See ParamTraits<vector<SerializedVar>>::Read.
 431   serialized_->reserve(count_);
 432   for (uint32_t i = 0; i < count_; i++) {
 433     // Just mimic what we do for regular OutParams.
 434     SerializedVar var;
 435     SerializedVarOutParam out(&var);
 436     *out.OutParam(dispatcher_) = array_[i];
 437     serialized_->push_back(var);
 438   }
 439
 440   // When returning arrays, the pepper code expects the caller to take
 441   // ownership of the array.
 442   free(array_);
 443 }
 444
 445 PP_Var** SerializedVarVectorOutParam::ArrayOutParam(Dispatcher* dispatcher) {
 446   DCHECK(!dispatcher_);  // Should only be called once.
 447   dispatcher_ = dispatcher;
 448   return &array_;
 449 }
 450
 451 SerializedVarTestConstructor::SerializedVarTestConstructor(
 452     const PP_Var& pod_var) {
 453   DCHECK(pod_var.type != PP_VARTYPE_STRING);
 454   inner_->ForceSetVarValueForTest(pod_var);
 455 }
 456
 457 SerializedVarTestConstructor::SerializedVarTestConstructor(
 458     const std::string& str) {
 459   inner_->ForceSetVarValueForTest(StringVar::StringToPPVar(str));
 460 }
 461
 462 SerializedVarTestReader::SerializedVarTestReader(const SerializedVar& var)
 463     : SerializedVar(var) {
 464 }
 465
 466 }  // namespace proxy
 467 }  // namespace ppapi