Byte array utils

Read

Get uint16_t, uint32_t values from the byte array as uint8_t, big-endian sequence.

    inline uint8_t G_BYTE(const uint8_t*& p) {
        return *(p)++; 
    }
    inline uint16_t G_WORD(const uint8_t*& p) {
        uint32_t r = *p++;
        r = (r << 8) + *p++;
        return r;
    }
    inline uint32_t G_DWORD(const uint8_t*& p) {
        uint32_t r = *p++;
        r = (r << 8) + *p++;
        r = (r << 8) + *p++;
        r = (r << 8) + *p++;
        return r;
    }

p is incremented by the number of bytes read.

Writing

Write uint8_t, big-endian uint16_t and uint32_t values to the byte array specified by pointer q.

    inline uint8_t& S_OCTET(uint8_t*& q, uint8_t c) {
        *q++ = c;
        return *q;
    }
    inline uint8_t& S_WORD(uint8_t*& q, uint16_t c) {
        *(q) = ((c) >> 8) & 0xff; (q)++;
        *(q) = ((c) & 0xff); (q)++;
        return *q;
    }
    inline uint8_t& S_DWORD(uint8_t*& q, uint32_t c) {
        *(q) = ((c) >> 24) & 0xff; (q)++;
        *(q) = ((c) >> 16) & 0xff; (q)++;
        *(q) = ((c) >>  8) & 0xff; (q)++;
        *(q) = ((c) & 0xff); (q)++;
        return *q;
    }

q is incremented by the number of bytes written.

Background

To simplify operations when generating and disassembling the data payload of wireless packets.

More simplified pack_bytes() and expand_bytes() are also available.