#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <limits.h>


uint8_t *_convert_c_int_to_bytes(int64_t value, size_t size)
{
    uint8_t *bytes = malloc(sizeof(uint8_t) * size);

    for (size_t i = 0; i < size; i++)
        bytes[i] = (value >> i * 8) & 0xFF;

    return bytes;
}


uint8_t *_convert_c_uint_to_bytes(uint64_t value, size_t size)
{
    uint8_t *bytes = malloc(sizeof(uint8_t) * size);

    for (size_t i = 0; i < size; i++)
        bytes[i] = (value >> i * 8) & 0xFF;

    return bytes;
}


int64_t _convert_bytes_to_c_int(uint8_t *bytes, size_t size)
{
    int64_t value = 0;

    for (size_t i = 0; i < size; i++)
        value += bytes[i] << (i * 8);

    return value;
}


uint64_t _convert_bytes_to_c_uint(uint8_t *bytes, size_t size)
{
    uint64_t value = 0;

    for (size_t i = 0; i < size; i++)
        value += bytes[i] << (i * 8);

    return value;
}


void dbg_print_bytes(uint8_t *bytes, size_t size)
{
    printf("uint8_t * {");
    for (size_t i = 0; i < size; i++)
        printf("%02x ", bytes[i]);
    printf("}\n");
}


int main(void)
{
    printf("uint64_t %lu -> ", ULONG_MAX);
    dbg_print_bytes(_convert_c_uint_to_bytes(ULONG_MAX, 8), 8);
    printf("int64_t %li -> ", LONG_MIN);
    dbg_print_bytes(_convert_c_int_to_bytes(LONG_MIN, 8), 8);
    printf("int64_t %li -> ", LONG_MAX);
    dbg_print_bytes(_convert_c_int_to_bytes(LONG_MAX, 8), 8);

    printf("uint64_t %lu -> uint8_t * -> uint64_t %lu\n", ULONG_MAX, _convert_bytes_to_c_uint(_convert_c_uint_to_bytes(ULONG_MAX, 8), 8));
    printf("int64_t %li -> uint8_t * -> int64_t %li\n", LONG_MIN, _convert_bytes_to_c_int(_convert_c_int_to_bytes(LONG_MIN, 8), 8));
    printf("int64_t %li -> uint8_t * -> int64_t %li\n", LONG_MAX, _convert_bytes_to_c_int(_convert_c_int_to_bytes(LONG_MAX, 8), 8));
    return 0;
}