byteswap.h

// Copyright (c) 2014-2016 The Bitcoin Core developers
// Copyright (c) 2024 bluezr
// Copyright (c) 2024 edtubbs
// Copyright (c) 2024 The Dogecoin Foundation
//
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.

#ifndef __LIBDOGECOIN_BYTESWAP_H__
#define __LIBDOGECOIN_BYTESWAP_H__

#include <dogecoin/dogecoin.h>

LIBDOGECOIN_BEGIN_DECL

#if defined(HAVE_BYTESWAP_H)
#include <byteswap.h>
#endif

#if defined(HAVE_CONFIG_H)
#include "libdogecoin-config.h"
#endif

#include <stdint.h>

static unsigned char bit_swap_table[256] =
{
  0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0,
  0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0,
  0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8,
  0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8,
  0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4,
  0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4,
  0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec,
  0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc,
  0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2,
  0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2,
  0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea,
  0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa,
  0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6,
  0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6,
  0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee,
  0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe,
  0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1,
  0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1,
  0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9,
  0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9,
  0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5,
  0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5,
  0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed,
  0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd,
  0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3,
  0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3,
  0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb,
  0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb,
  0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7,
  0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7,
  0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef,
  0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff,
};

#if HAVE_DECL_BSWAP_8 == 0
DISABLE_WARNING_PUSH
DISABLE_WARNING(-Wunused-function)
LIBDOGECOIN_API static uint8_t bswap_8(uint8_t x)
{
    return bit_swap_table[x];
}
DISABLE_WARNING_POP
#endif

#if defined(__APPLE__)

#if !defined(bswap_16)

// Mac OS X / Darwin features; we include a check for bswap_16 because if it is already defined, protobuf has
// defined these macros for us already; if it isn't, we do it ourselves. In either case, we get the exact same
// result regardless which path was taken
#include <libkern/OSByteOrder.h>
#define bswap_16(x) OSSwapInt16(x)
#define bswap_32(x) OSSwapInt32(x)
#define bswap_64(x) OSSwapInt64(x)

#endif // !defined(bswap_16)

#else
// Non-Mac OS X / non-Darwin

#if HAVE_DECL_BSWAP_16 == 0
LIBDOGECOIN_API inline uint16_t bswap_16(uint16_t x)
{
    return (x >> 8) | ((x & 0x00ff) << 8);
}
#endif // HAVE_DECL_BSWAP16

#if HAVE_DECL_BSWAP_32 == 0
LIBDOGECOIN_API inline uint32_t bswap_32(uint32_t x)
{
    return (((x & 0xff000000U) >> 24) | ((x & 0x00ff0000U) >> 8) |
            ((x & 0x0000ff00U) << 8) | ((x & 0x000000ffU) << 24));
}
#endif // HAVE_DECL_BSWAP32

#if HAVE_DECL_BSWAP_64 == 0
LIBDOGECOIN_API inline uint64_t bswap_64(uint64_t x)
{
     return (((x & 0xff00000000000000ull) >> 56)
          | ((x & 0x00ff000000000000ull) >> 40)
          | ((x & 0x0000ff0000000000ull) >> 24)
          | ((x & 0x000000ff00000000ull) >> 8)
          | ((x & 0x00000000ff000000ull) << 8)
          | ((x & 0x0000000000ff0000ull) << 24)
          | ((x & 0x000000000000ff00ull) << 40)
          | ((x & 0x00000000000000ffull) << 56));
}
#endif // HAVE_DECL_BSWAP64

#endif // defined(__APPLE__)

LIBDOGECOIN_END_DECL

#endif // __LIBDOGECOIN_BYTESWAP_H__