Quick benchmark - Randomness via CPU

random.cpp

#include <stdio.h>
#include <stdlib.h>
#include <time.h>

// Function to convert a byte into its hexadecimal string representation
void byteToHex(unsigned char byte, char hexStr[3]) {
    const char hexDigits[] = "0123456789abcdef";
    hexStr[0] = hexDigits[byte >> 4];  // Extract the high nibble (4 bits) and find its hex character
    hexStr[1] = hexDigits[byte & 0x0F];  // Extract the low nibble and find its hex character
    hexStr[2] = '\0';  // Null-terminate the string
}

int main() {
    const size_t numIterations = 1000;  // Number of times to repeat the process
    const size_t numBytes = 1000000;  // Number of random bytes to generate per iteration
    for (size_t j = 0; j < numIterations; ++j) {
        unsigned char* randomBytes = (unsigned char*)malloc(numBytes);  // Explicit cast needed here
        char* hexString = (char*)malloc(numBytes * 2 + 1);  // Each byte -> 2 hex characters, +1 for null terminator, explicit cast needed here
        if (!randomBytes || !hexString) {
            printf("Memory allocation failed\n");
            return 1;
        }

        // Generate random bytes
        for (size_t i = 0; i < numBytes; ++i) {
            randomBytes[i] = (unsigned char)(rand() % 256);
        }

        // Convert bytes to hex string
        for (size_t i = 0; i < numBytes; ++i) {
            byteToHex(randomBytes[i], &hexString[i * 2]);
        }

        // Normally, you would do something with hexString here

        free(randomBytes);
        free(hexString);
    }

    return 0;
}