////////////////////////////////////////////////////////////////////////////////
// Copyright 2017 Google LLC.
//
// This software is licensed under the terms defined in the Widevine Master
// License Agreement. For a copy of this agreement, please contact
// widevine-licensing@google.com.
////////////////////////////////////////////////////////////////////////////////

#ifndef UTIL_ENDIAN_ENDIAN_H_
#define UTIL_ENDIAN_ENDIAN_H_

#include <netinet/in.h>
#include <cstdint>


namespace widevine {

// Utilities to convert numbers between the current hosts's native byte
// order and big-endian byte order (same as network byte order)
class BigEndian {
 public:
  static uint32_t Load32(const char* data) {
    return (data[0] << 24) | (data[1] << 16) | (data[2] << 8) | data[3];
  }

  static uint64_t Load64(const char* data) {
    return ((static_cast<uint64_t>(Load32(data)) << 32) | Load32(data + 4));
  }

  static void Store32(void* p, uint32_t data) {
    for (int i = 0; i < 4; ++i)
      (reinterpret_cast<uint8_t*>(p))[i] = (data >> ((3 - i) * 8)) & 0xFF;
  }
};      // BigEndian

inline uint64_t gntohll(uint64_t n) {
  uint64_t retval;
#if __BYTE_ORDER == __BIG_ENDIAN
  retval = n;
#else
  retval = ((uint64_t) ntohl(n & 0xFFFFFFFFLLU)) << 32;
  retval |= ntohl((n & 0xFFFFFFFF00000000LLU) >> 32);
#endif
  return(retval);
}

}  // namespace widevine

#endif  // UTIL_ENDIAN_ENDIAN_H_