Unpack Little and Big Endian Unsigned Integers uint16_t, uint32_t, uint64_t

unpack.h

/********************************************************************************
*
*  Copyright (c) Simon Downey <[email protected]> <https://github.com/sleepdefic1t>
*
*  The MIT License (MIT)
*
*  Permission is hereby granted, free of charge, to any person obtaining a copy of
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#include <cstdint>

//////////////////////////////////////////////////////////////////////

#define FLAG_8_BYTE     0xFFFFFFFFFFFFFFFF
#define FLAG_4_BYTE     0xFFFFFFFF
#define FLAG_2_BYTE     0xFFFF
#define FLAG_1_BYTE     0xFF

//////////////////////////////////////////////////////////////////////

#define unpack2LE(src, offset)                                                  \
        ((((uint16_t)src[offset]                    & FLAG_1_BYTE)          |   \
          ((uint16_t)src[offset + 1U]               & FLAG_1_BYTE)  << 8U)      \
                                                    & FLAG_2_BYTE)

#define unpack4LE(src, offset)                                                  \
        ((((uint32_t)unpack2LE(src, offset)         & FLAG_2_BYTE)          |   \
          ((uint32_t)unpack2LE(src, offset + 2U)    & FLAG_2_BYTE)  << 16U)     \
                                                    & FLAG_4_BYTE)

#define unpack8LE(src, offset)                                                  \
        ((((uint64_t)unpack4LE(src, offset)         & FLAG_4_BYTE)          |   \
          ((uint64_t)unpack4LE(src, offset + 4U)    & FLAG_4_BYTE)  << 32U)     \
                                                    & FLAG_8_BYTE)

//////////////////////////////////////////////////////////////////////

#define unpack2BE(src, offset)                                                  \
        ((((uint16_t)src[offset]                    & FLAG_1_BYTE)  << 8U   |   \
          ((uint16_t)src[offset + 1U]               & FLAG_1_BYTE))             \
                                                    & FLAG_2_BYTE)

#define unpack4BE(src, offset)                                                  \
        ((((uint32_t)unpack2BE(src, offset)         & FLAG_2_BYTE)  << 16U) |   \
          ((uint32_t)unpack2BE(src, offset + 2U)    & FLAG_2_BYTE)              \
                                                    & FLAG_4_BYTE)

#define unpack8BE(src, offset)                                                  \
        ((((uint64_t)unpack4BE(src, offset)         & FLAG_4_BYTE)  << 32U) |   \
          ((uint64_t)unpack4BE(src, offset + 4U)    & FLAG_4_BYTE)              \
                                                    & FLAG_8_BYTE)

//////////////////////////////////////////////////////////////////////