Blink-compatible serialization of numbers.

src/value-serializer.h

 // 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.
 
 #ifndef V8_VALUE_SERIALIZER_H_
 #define V8_VALUE_SERIALIZER_H_
 
 #include <cstdint>
 #include <vector>
 
 #include "include/v8.h"
 #include "src/base/compiler-specific.h"
 #include "src/base/macros.h"
 #include "src/vector.h"
 
 namespace v8 {
 namespace internal {
 
+class HeapNumber;
 class Isolate;
 class Object;
 class Oddball;
+class Smi;
 
 enum class SerializationTag : uint8_t;
 
 /**
  * Writes V8 objects in a binary format that allows the objects to be cloned
  * according to the HTML structured clone algorithm.
  *
  * Format is based on Blink's previous serialization logic.
  */
 class ValueSerializer {
@@ skipping 15 matching lines @@
    * Returns the stored data. This serializer should not be used once the buffer
    * is released. The contents are undefined if a previous write has failed.
    */
   std::vector<uint8_t> ReleaseBuffer() { return std::move(buffer_); }
 
  private:
   // Writing the wire format.
   void WriteTag(SerializationTag tag);
   template <typename T>
   void WriteVarint(T value);
+  template <typename T>
+  void WriteZigZag(T value);
+  void WriteDouble(double value);
 
   // Writing V8 objects of various kinds.
   void WriteOddball(Oddball* oddball);
+  void WriteSmi(Smi* smi);
+  void WriteHeapNumber(HeapNumber* number);
 
   std::vector<uint8_t> buffer_;
 
   DISALLOW_COPY_AND_ASSIGN(ValueSerializer);
 };
 
 /*
  * Deserializes values from data written with ValueSerializer, or a compatible
  * implementation.
  */
 class ValueDeserializer {
  public:
   ValueDeserializer(Isolate* isolate, Vector<const uint8_t> data);
   ~ValueDeserializer();
 
   /*
    * Runs version detection logic, which may fail if the format is invalid.
    */
   Maybe<bool> ReadHeader() WARN_UNUSED_RESULT;
 
   /*
    * Deserializes a V8 object from the buffer.
    */
   MaybeHandle<Object> ReadObject() WARN_UNUSED_RESULT;
 
  private:
   Maybe<SerializationTag> ReadTag() WARN_UNUSED_RESULT;
   template <typename T>
   Maybe<T> ReadVarint() WARN_UNUSED_RESULT;
+  template <typename T>
+  Maybe<T> ReadZigZag() WARN_UNUSED_RESULT;
+  Maybe<double> ReadDouble() WARN_UNUSED_RESULT;
 
   Isolate* const isolate_;
   const uint8_t* position_;
   const uint8_t* const end_;
   uint32_t version_ = 0;
 
   DISALLOW_COPY_AND_ASSIGN(ValueDeserializer);
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_VALUE_SERIALIZER_H_