In QUIC v39, read and write integers and floating numbers in big endian.

net/quic/core/quic_data_reader.h

 // Copyright (c) 2012 The Chromium 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 NET_QUIC_CORE_QUIC_DATA_READER_H_
 #define NET_QUIC_CORE_QUIC_DATA_READER_H_
 
 #include <cstddef>
 #include <cstdint>
 
@@ skipping 107 matching lines @@
 
   // Returns the number of bytes remaining to be read.
   size_t BytesRemaining() const;
 
   // Returns the next byte that to be read. Must not be called when there are no
   // bytes to be read.
   //
   // DOES NOT forward the internal iterator.
   uint8_t PeekByte() const;
 
+  void set_endianness(Endianness endianness) { endianness_ = endianness; }
+
  private:
   // Returns true if the underlying buffer has enough room to read the given
   // amount of bytes.
   bool CanRead(size_t bytes) const;
 
   // To be called when a read fails for any reason.
   void OnFailure();
 
   // The data buffer that we're reading from.
   const char* data_;
@@ skipping 11 matching lines @@
 
   // The endianness to read integers and floating numbers.
   Endianness endianness_;
 
   DISALLOW_COPY_AND_ASSIGN(QuicDataReader);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_CORE_QUIC_DATA_READER_H_