Revert of [d8] Use ValueSerializer for postMessage (instead of ad-hoc serializer)

src/value-serializer.cc

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/value-serializer.h"
 
 #include <type_traits>
 
 #include "src/base/logging.h"
 #include "src/conversions.h"
@@ skipping 199 matching lines @@
   WriteRawBytes(chars.begin(), chars.length() * sizeof(uint8_t));
 }
 
 void ValueSerializer::WriteTwoByteString(Vector<const uc16> chars) {
   // Warning: this uses host endianness.
   WriteVarint<uint32_t>(chars.length() * sizeof(uc16));
   WriteRawBytes(chars.begin(), chars.length() * sizeof(uc16));
 }
 
 void ValueSerializer::WriteRawBytes(const void* source, size_t length) {
-  uint8_t* dest;
-  if (ReserveRawBytes(length).To(&dest)) {
-    memcpy(dest, source, length);
-  }
+  memcpy(ReserveRawBytes(length), source, length);
 }
 
-Maybe<uint8_t*> ValueSerializer::ReserveRawBytes(size_t bytes) {
+uint8_t* ValueSerializer::ReserveRawBytes(size_t bytes) {
   size_t old_size = buffer_size_;
   size_t new_size = old_size + bytes;
-  if (new_size > buffer_capacity_) {
-    bool ok;
-    if (!ExpandBuffer(new_size).To(&ok)) {
-      return Nothing<uint8_t*>();
-    }
-  }
+  if (new_size > buffer_capacity_) ExpandBuffer(new_size);
   buffer_size_ = new_size;
-  return Just(&buffer_[old_size]);
+  return &buffer_[old_size];
 }
 
-Maybe<bool> ValueSerializer::ExpandBuffer(size_t required_capacity) {
+void ValueSerializer::ExpandBuffer(size_t required_capacity) {
   DCHECK_GT(required_capacity, buffer_capacity_);
   size_t requested_capacity =
       std::max(required_capacity, buffer_capacity_ * 2) + 64;
   size_t provided_capacity = 0;
   void* new_buffer = nullptr;
   if (delegate_) {
     new_buffer = delegate_->ReallocateBufferMemory(buffer_, requested_capacity,
                                                    &provided_capacity);
   } else {
     new_buffer = realloc(buffer_, requested_capacity);
     provided_capacity = requested_capacity;
   }
-  if (new_buffer) {
-    DCHECK(provided_capacity >= requested_capacity);
-    buffer_ = reinterpret_cast<uint8_t*>(new_buffer);
-    buffer_capacity_ = provided_capacity;
-    return Just(true);
-  } else {
-    out_of_memory_ = true;
-    return Nothing<bool>();
-  }
+  DCHECK_GE(provided_capacity, requested_capacity);
+  buffer_ = reinterpret_cast<uint8_t*>(new_buffer);
+  buffer_capacity_ = provided_capacity;
 }
 
 void ValueSerializer::WriteUint32(uint32_t value) {
   WriteVarint<uint32_t>(value);
 }
 
 void ValueSerializer::WriteUint64(uint64_t value) {
   WriteVarint<uint64_t>(value);
 }
 
@@ skipping 10 matching lines @@
 }
 
 void ValueSerializer::TransferArrayBuffer(uint32_t transfer_id,
                                           Handle<JSArrayBuffer> array_buffer) {
   DCHECK(!array_buffer_transfer_map_.Find(array_buffer));
   DCHECK(!array_buffer->is_shared());
   array_buffer_transfer_map_.Set(array_buffer, transfer_id);
 }
 
 Maybe<bool> ValueSerializer::WriteObject(Handle<Object> object) {
-  out_of_memory_ = false;
   if (object->IsSmi()) {
     WriteSmi(Smi::cast(*object));
-    return ThrowIfOutOfMemory();
+    return Just(true);
   }
 
   DCHECK(object->IsHeapObject());
   switch (HeapObject::cast(*object)->map()->instance_type()) {
     case ODDBALL_TYPE:
       WriteOddball(Oddball::cast(*object));
-      return ThrowIfOutOfMemory();
+      return Just(true);
     case HEAP_NUMBER_TYPE:
     case MUTABLE_HEAP_NUMBER_TYPE:
       WriteHeapNumber(HeapNumber::cast(*object));
-      return ThrowIfOutOfMemory();
+      return Just(true);
     case JS_TYPED_ARRAY_TYPE:
     case JS_DATA_VIEW_TYPE: {
       // Despite being JSReceivers, these have their wrapped buffer serialized
       // first. That makes this logic a little quirky, because it needs to
       // happen before we assign object IDs.
       // TODO(jbroman): It may be possible to avoid materializing a typed
       // array's buffer here.
       Handle<JSArrayBufferView> view = Handle<JSArrayBufferView>::cast(object);
       if (!id_map_.Find(view)) {
         Handle<JSArrayBuffer> buffer(
             view->IsJSTypedArray()
                 ? Handle<JSTypedArray>::cast(view)->GetBuffer()
                 : handle(JSArrayBuffer::cast(view->buffer()), isolate_));
         if (!WriteJSReceiver(buffer).FromMaybe(false)) return Nothing<bool>();
       }
       return WriteJSReceiver(view);
     }
     default:
       if (object->IsString()) {
         WriteString(Handle<String>::cast(object));
-        return ThrowIfOutOfMemory();
+        return Just(true);
       } else if (object->IsJSReceiver()) {
         return WriteJSReceiver(Handle<JSReceiver>::cast(object));
       } else {
         ThrowDataCloneError(MessageTemplate::kDataCloneError, object);
         return Nothing<bool>();
       }
   }
 }
 
 void ValueSerializer::WriteOddball(Oddball* oddball) {
@@ skipping 40 matching lines @@
     // TODO(jbroman): In a future format version, consider adding a tag for
     // Latin-1 strings, so that this can be skipped.
     WriteTag(SerializationTag::kUtf8String);
     Vector<const uint8_t> chars = flat.ToOneByteVector();
     if (String::IsAscii(chars.begin(), chars.length())) {
       WriteOneByteString(chars);
     } else {
       v8::Local<v8::String> api_string = Utils::ToLocal(string);
       uint32_t utf8_length = api_string->Utf8Length();
       WriteVarint(utf8_length);
-      uint8_t* dest;
-      if (ReserveRawBytes(utf8_length).To(&dest)) {
-        api_string->WriteUtf8(reinterpret_cast<char*>(dest), utf8_length,
-                              nullptr, v8::String::NO_NULL_TERMINATION);
-      }
+      api_string->WriteUtf8(
+          reinterpret_cast<char*>(ReserveRawBytes(utf8_length)), utf8_length,
+          nullptr, v8::String::NO_NULL_TERMINATION);
     }
   } else if (flat.IsTwoByte()) {
     Vector<const uc16> chars = flat.ToUC16Vector();
     uint32_t byte_length = chars.length() * sizeof(uc16);
     // The existing reading code expects 16-byte strings to be aligned.
     if ((buffer_size_ + 1 + BytesNeededForVarint(byte_length)) & 1)
       WriteTag(SerializationTag::kPadding);
     WriteTag(SerializationTag::kTwoByteString);
     WriteTwoByteString(chars);
   } else {
     UNREACHABLE();
   }
 }
 
 Maybe<bool> ValueSerializer::WriteJSReceiver(Handle<JSReceiver> receiver) {
   // If the object has already been serialized, just write its ID.
   uint32_t* id_map_entry = id_map_.Get(receiver);
   if (uint32_t id = *id_map_entry) {
     WriteTag(SerializationTag::kObjectReference);
     WriteVarint(id - 1);
-    return ThrowIfOutOfMemory();
+    return Just(true);
   }
 
   // Otherwise, allocate an ID for it.
   uint32_t id = next_id_++;
   *id_map_entry = id + 1;
 
   // Eliminate callable and exotic objects, which should not be serialized.
   InstanceType instance_type = receiver->map()->instance_type();
   if (receiver->IsCallable() || (IsSpecialReceiverInstanceType(instance_type) &&
                                  instance_type != JS_SPECIAL_API_OBJECT_TYPE)) {
@@ skipping 19 matching lines @@
       } else if (JSObject::GetInternalFieldCount(map)) {
         return WriteHostObject(js_object);
       } else {
         return WriteJSObject(js_object);
       }
     }
     case JS_SPECIAL_API_OBJECT_TYPE:
       return WriteHostObject(Handle<JSObject>::cast(receiver));
     case JS_DATE_TYPE:
       WriteJSDate(JSDate::cast(*receiver));
-      return ThrowIfOutOfMemory();
+      return Just(true);
     case JS_VALUE_TYPE:
       return WriteJSValue(Handle<JSValue>::cast(receiver));
     case JS_REGEXP_TYPE:
       WriteJSRegExp(JSRegExp::cast(*receiver));
-      return ThrowIfOutOfMemory();
+      return Just(true);
     case JS_MAP_TYPE:
       return WriteJSMap(Handle<JSMap>::cast(receiver));
     case JS_SET_TYPE:
       return WriteJSSet(Handle<JSSet>::cast(receiver));
     case JS_ARRAY_BUFFER_TYPE:
       return WriteJSArrayBuffer(Handle<JSArrayBuffer>::cast(receiver));
     case JS_TYPED_ARRAY_TYPE:
     case JS_DATA_VIEW_TYPE:
       return WriteJSArrayBufferView(JSArrayBufferView::cast(*receiver));
     default:
@@ skipping 40 matching lines @@
 
     if (!WriteObject(key).FromMaybe(false) ||
         !WriteObject(value).FromMaybe(false)) {
       return Nothing<bool>();
     }
     properties_written++;
   }
 
   WriteTag(SerializationTag::kEndJSObject);
   WriteVarint<uint32_t>(properties_written);
-  return ThrowIfOutOfMemory();
+  return Just(true);
 }
 
 Maybe<bool> ValueSerializer::WriteJSObjectSlow(Handle<JSObject> object) {
   WriteTag(SerializationTag::kBeginJSObject);
   Handle<FixedArray> keys;
   uint32_t properties_written;
   if (!KeyAccumulator::GetKeys(object, KeyCollectionMode::kOwnOnly,
                                ENUMERABLE_STRINGS)
            .ToHandle(&keys) ||
       !WriteJSObjectPropertiesSlow(object, keys).To(&properties_written)) {
     return Nothing<bool>();
   }
   WriteTag(SerializationTag::kEndJSObject);
   WriteVarint<uint32_t>(properties_written);
-  return ThrowIfOutOfMemory();
+  return Just(true);
 }
 
 Maybe<bool> ValueSerializer::WriteJSArray(Handle<JSArray> array) {
   uint32_t length = 0;
   bool valid_length = array->length()->ToArrayLength(&length);
   DCHECK(valid_length);
   USE(valid_length);
 
   // To keep things simple, for now we decide between dense and sparse
   // serialization based on elements kind. A more principled heuristic could
@@ skipping 84 matching lines @@
     if (!KeyAccumulator::GetKeys(array, KeyCollectionMode::kOwnOnly,
                                  ENUMERABLE_STRINGS)
              .ToHandle(&keys) ||
         !WriteJSObjectPropertiesSlow(array, keys).To(&properties_written)) {
       return Nothing<bool>();
     }
     WriteTag(SerializationTag::kEndSparseJSArray);
     WriteVarint<uint32_t>(properties_written);
     WriteVarint<uint32_t>(length);
   }
-  return ThrowIfOutOfMemory();
+  return Just(true);
 }
 
 void ValueSerializer::WriteJSDate(JSDate* date) {
   WriteTag(SerializationTag::kDate);
   WriteDouble(date->value()->Number());
 }
 
 Maybe<bool> ValueSerializer::WriteJSValue(Handle<JSValue> value) {
   Object* inner_value = value->value();
   if (inner_value->IsTrue(isolate_)) {
     WriteTag(SerializationTag::kTrueObject);
   } else if (inner_value->IsFalse(isolate_)) {
     WriteTag(SerializationTag::kFalseObject);
   } else if (inner_value->IsNumber()) {
     WriteTag(SerializationTag::kNumberObject);
     WriteDouble(inner_value->Number());
   } else if (inner_value->IsString()) {
     // TODO(jbroman): Replace UTF-8 encoding with the same options available for
     // ordinary strings.
     WriteTag(SerializationTag::kStringObject);
     v8::Local<v8::String> api_string =
         Utils::ToLocal(handle(String::cast(inner_value), isolate_));
     uint32_t utf8_length = api_string->Utf8Length();
     WriteVarint(utf8_length);
-    uint8_t* dest;
-    if (ReserveRawBytes(utf8_length).To(&dest)) {
-      api_string->WriteUtf8(reinterpret_cast<char*>(dest), utf8_length, nullptr,
-                            v8::String::NO_NULL_TERMINATION);
-    }
+    api_string->WriteUtf8(reinterpret_cast<char*>(ReserveRawBytes(utf8_length)),
+                          utf8_length, nullptr,
+                          v8::String::NO_NULL_TERMINATION);
   } else {
     DCHECK(inner_value->IsSymbol());
     ThrowDataCloneError(MessageTemplate::kDataCloneError, value);
     return Nothing<bool>();
   }
-  return ThrowIfOutOfMemory();
+  return Just(true);
 }
 
 void ValueSerializer::WriteJSRegExp(JSRegExp* regexp) {
   WriteTag(SerializationTag::kRegExp);
   v8::Local<v8::String> api_string =
       Utils::ToLocal(handle(regexp->Pattern(), isolate_));
   uint32_t utf8_length = api_string->Utf8Length();
   WriteVarint(utf8_length);
-  uint8_t* dest;
-  if (ReserveRawBytes(utf8_length).To(&dest)) {
-    api_string->WriteUtf8(reinterpret_cast<char*>(dest), utf8_length, nullptr,
-                          v8::String::NO_NULL_TERMINATION);
-  }
+  api_string->WriteUtf8(reinterpret_cast<char*>(ReserveRawBytes(utf8_length)),
+                        utf8_length, nullptr, v8::String::NO_NULL_TERMINATION);
   WriteVarint(static_cast<uint32_t>(regexp->GetFlags()));
 }
 
 Maybe<bool> ValueSerializer::WriteJSMap(Handle<JSMap> map) {
   // First copy the key-value pairs, since getters could mutate them.
   Handle<OrderedHashMap> table(OrderedHashMap::cast(map->table()));
   int length = table->NumberOfElements() * 2;
   Handle<FixedArray> entries = isolate_->factory()->NewFixedArray(length);
   {
     DisallowHeapAllocation no_gc;
@@ skipping 11 matching lines @@
 
   // Then write it out.
   WriteTag(SerializationTag::kBeginJSMap);
   for (int i = 0; i < length; i++) {
     if (!WriteObject(handle(entries->get(i), isolate_)).FromMaybe(false)) {
       return Nothing<bool>();
     }
   }
   WriteTag(SerializationTag::kEndJSMap);
   WriteVarint<uint32_t>(length);
-  return ThrowIfOutOfMemory();
+  return Just(true);
 }
 
 Maybe<bool> ValueSerializer::WriteJSSet(Handle<JSSet> set) {
   // First copy the element pointers, since getters could mutate them.
   Handle<OrderedHashSet> table(OrderedHashSet::cast(set->table()));
   int length = table->NumberOfElements();
   Handle<FixedArray> entries = isolate_->factory()->NewFixedArray(length);
   {
     DisallowHeapAllocation no_gc;
     Oddball* the_hole = isolate_->heap()->the_hole_value();
     int capacity = table->UsedCapacity();
     int result_index = 0;
     for (int i = 0; i < capacity; i++) {
       Object* key = table->KeyAt(i);
       if (key == the_hole) continue;
       entries->set(result_index++, key);
     }
     DCHECK_EQ(result_index, length);
   }
 
   // Then write it out.
   WriteTag(SerializationTag::kBeginJSSet);
   for (int i = 0; i < length; i++) {
     if (!WriteObject(handle(entries->get(i), isolate_)).FromMaybe(false)) {
       return Nothing<bool>();
     }
   }
   WriteTag(SerializationTag::kEndJSSet);
   WriteVarint<uint32_t>(length);
-  return ThrowIfOutOfMemory();
+  return Just(true);
 }
 
 Maybe<bool> ValueSerializer::WriteJSArrayBuffer(
     Handle<JSArrayBuffer> array_buffer) {
   if (array_buffer->is_shared()) {
     if (!delegate_) {
       ThrowDataCloneError(MessageTemplate::kDataCloneError, array_buffer);
       return Nothing<bool>();
     }
 
     v8::Isolate* v8_isolate = reinterpret_cast<v8::Isolate*>(isolate_);
     Maybe<uint32_t> index = delegate_->GetSharedArrayBufferId(
         v8_isolate, Utils::ToLocalShared(array_buffer));
     RETURN_VALUE_IF_SCHEDULED_EXCEPTION(isolate_, Nothing<bool>());
 
     WriteTag(SerializationTag::kSharedArrayBuffer);
     WriteVarint(index.FromJust());
-    return ThrowIfOutOfMemory();
+    return Just(true);
   }
 
   uint32_t* transfer_entry = array_buffer_transfer_map_.Find(array_buffer);
   if (transfer_entry) {
     WriteTag(SerializationTag::kArrayBufferTransfer);
     WriteVarint(*transfer_entry);
-    return ThrowIfOutOfMemory();
+    return Just(true);
   }
   if (array_buffer->was_neutered()) {
     ThrowDataCloneError(MessageTemplate::kDataCloneErrorNeuteredArrayBuffer);
     return Nothing<bool>();
   }
   double byte_length = array_buffer->byte_length()->Number();
   if (byte_length > std::numeric_limits<uint32_t>::max()) {
     ThrowDataCloneError(MessageTemplate::kDataCloneError, array_buffer);
     return Nothing<bool>();
   }
   WriteTag(SerializationTag::kArrayBuffer);
   WriteVarint<uint32_t>(byte_length);
   WriteRawBytes(array_buffer->backing_store(), byte_length);
-  return ThrowIfOutOfMemory();
+  return Just(true);
 }
 
 Maybe<bool> ValueSerializer::WriteJSArrayBufferView(JSArrayBufferView* view) {
   WriteTag(SerializationTag::kArrayBufferView);
   ArrayBufferViewTag tag = ArrayBufferViewTag::kInt8Array;
   if (view->IsJSTypedArray()) {
     switch (JSTypedArray::cast(view)->type()) {
 #define TYPED_ARRAY_CASE(Type, type, TYPE, ctype, size) \
   case kExternal##Type##Array:                          \
     tag = ArrayBufferViewTag::k##Type##Array;           \
     break;
       TYPED_ARRAYS(TYPED_ARRAY_CASE)
 #undef TYPED_ARRAY_CASE
     }
   } else {
     DCHECK(view->IsJSDataView());
     tag = ArrayBufferViewTag::kDataView;
   }
   WriteVarint(static_cast<uint8_t>(tag));
   WriteVarint(NumberToUint32(view->byte_offset()));
   WriteVarint(NumberToUint32(view->byte_length()));
-  return ThrowIfOutOfMemory();
+  return Just(true);
 }
 
 Maybe<bool> ValueSerializer::WriteWasmModule(Handle<JSObject> object) {
   Handle<WasmCompiledModule> compiled_part(
       WasmCompiledModule::cast(object->GetInternalField(0)), isolate_);
   WasmEncodingTag encoding_tag = WasmEncodingTag::kRawBytes;
   WriteTag(SerializationTag::kWasmModule);
   WriteRawBytes(&encoding_tag, sizeof(encoding_tag));
 
   Handle<String> wire_bytes(compiled_part->module_bytes(), isolate_);
   int wire_bytes_length = wire_bytes->length();
   WriteVarint<uint32_t>(wire_bytes_length);
-  uint8_t* destination;
-  if (ReserveRawBytes(wire_bytes_length).To(&destination)) {
-    String::WriteToFlat(*wire_bytes, destination, 0, wire_bytes_length);
-  }
+  uint8_t* destination = ReserveRawBytes(wire_bytes_length);
+  String::WriteToFlat(*wire_bytes, destination, 0, wire_bytes_length);
 
   std::unique_ptr<ScriptData> script_data =
       WasmCompiledModuleSerializer::SerializeWasmModule(isolate_,
                                                         compiled_part);
   int script_data_length = script_data->length();
   WriteVarint<uint32_t>(script_data_length);
   WriteRawBytes(script_data->data(), script_data_length);
 
-  return ThrowIfOutOfMemory();
+  return Just(true);
 }
 
 Maybe<bool> ValueSerializer::WriteHostObject(Handle<JSObject> object) {
   if (!delegate_) {
     isolate_->Throw(*isolate_->factory()->NewError(
         isolate_->error_function(), MessageTemplate::kDataCloneError, object));
     return Nothing<bool>();
   }
   v8::Isolate* v8_isolate = reinterpret_cast<v8::Isolate*>(isolate_);
   Maybe<bool> result =
@@ skipping 30 matching lines @@
   }
   return Just(properties_written);
 }
 
 void ValueSerializer::ThrowDataCloneError(
     MessageTemplate::Template template_index) {
   return ThrowDataCloneError(template_index,
                              isolate_->factory()->empty_string());
 }
 
-Maybe<bool> ValueSerializer::ThrowIfOutOfMemory() {
-  if (out_of_memory_) {
-    ThrowDataCloneError(MessageTemplate::kDataCloneErrorOutOfMemory);
-    return Nothing<bool>();
-  }
-  return Just(true);
-}
-
 void ValueSerializer::ThrowDataCloneError(
     MessageTemplate::Template template_index, Handle<Object> arg0) {
   Handle<String> message =
       MessageTemplate::FormatMessage(isolate_, template_index, arg0);
   if (delegate_) {
     delegate_->ThrowDataCloneError(Utils::ToLocal(message));
   } else {
     isolate_->Throw(
         *isolate_->factory()->NewError(isolate_->error_function(), message));
   }
@@ skipping 1013 matching lines @@
   if (stack.size() != 1) {
     isolate_->Throw(*isolate_->factory()->NewError(
         MessageTemplate::kDataCloneDeserializationError));
     return MaybeHandle<Object>();
   }
   return scope.CloseAndEscape(stack[0]);
 }
 
 }  // namespace internal
 }  // namespace v8