ptth/bare_minimum_crypto/cpp/string_helpers.cpp

#include "string_helpers.h"

#include <iostream>

#include "cpp-base64/base64.h"

namespace BareMinimumCrypto {
	using namespace std;
	
	Bytes copy_to_bytes (const string & s) {
		return Bytes ((const uint8_t *)&s [0], (const uint8_t *)&s [s.size ()]);
	}
	
	string base64_encode (const Bytes & v) {
		return ::base64_encode (string_view ((const char *)v.data (), v.size ()));
	}
	
	optional <Bytes> base64_decode (const string & s) {
		try {
			const auto decoded = ::base64_decode (s);
			return copy_to_bytes (decoded);
		}
		catch (const exception &) {
			return nullopt;
		}
	}
	
	int test_base64 () {
		// I assume that char is 8 bits
		// char is C++ nonsense inherited from C nonsense
		if (sizeof (char) != sizeof (uint8_t)) {
			cerr << "char is not the same size as uint8_t" << endl;
			return 1;
		}
		
		Bytes v {1, 2, 3, 4, 5, 6};
		const auto s = base64_encode (v);
		
		if (s != "AQIDBAUG") {
			cerr << "Base64 encoding failed" << endl;
			return 1;
		}
		
		// Trivial decode
		const auto v2 = std::move (*base64_decode (s));
		
		if (v2 != v) {
			cerr << "Base64 trivial decode failed" << endl;
			return 1;
		}
		
		// Decode should fail
		const auto v3 = base64_decode ("AQIDBAUG.");
		
		if (v3 != nullopt) {
			cerr << "Base64 decode should have failed" << endl;
			return 1;
		}
		
		return 0;
	}
}