Function encode

fdbrpc/Base64UrlEncode.cpp:30–68

}

int encode(const uint8_t* __restrict plaintextIn, int lengthIn, uint8_t* __restrict codeOut) noexcept {
	const uint8_t* plainchar = plaintextIn;
	const uint8_t* const plaintextEnd = plaintextIn + lengthIn;
	uint8_t* codechar = codeOut;
	uint8_t result = 0;
	uint8_t fragment = 0;

	while (1) {
		if (plainchar == plaintextEnd) {
			return codechar - codeOut;
		}
		// byte 1 of 3
		fragment = *plainchar++;
		result = (fragment & 0x0fc) >> 2;
		*codechar++ = encodeValue(result);
		result = (fragment & 0x003) << 4;
		if (plainchar == plaintextEnd) {
			*codechar++ = encodeValue(result);
			return codechar - codeOut;
		}
		// byte 2 of 3
		fragment = *plainchar++;
		result |= (fragment & 0x0f0) >> 4;
		*codechar++ = encodeValue(result);
		result = (fragment & 0x00f) << 2;
		if (plainchar == plaintextEnd) {
			*codechar++ = encodeValue(result);
			return codechar - codeOut;
		}
		// byte 3 of 3
		fragment = *plainchar++;
		result |= (fragment & 0x0c0) >> 6;
		*codechar++ = encodeValue(result);
		result = (fragment & 0x03f) >> 0;
		*codechar++ = encodeValue(result);
	}
	/* control should not reach here */
	return codechar - codeOut;
}

int encodedLength(int dataLength) noexcept {
	auto r = dataLength % 3;