C 数值类型与字节数组相互转化

C 数据类型与字节数组相互转化

uint16_t -> bytes

uint8_t uint16_t2bytes(uint8_t* buffer, uint16_t data)
{
	if(buffer == NULL) return 0;
	uint16_t tmp2byte = data;
	*buffer = (tmp2byte & 0xff00) >> 8;
	*(++buffer) = tmp2byte & 0x00ff;
	return 2;
}

bytes -> uint16_t

uint8_t bytes2uint16_t(uint8_t* buffer, uint16_t* data)
{
	if(buffer == NULL) return 0;
	*data = (*buffer << 8) + *(buffer + 1);
	return 2;
}

double -> bytes

uint8_t double2bytes(uint8_t* buffer, double data)
{
	if(buffer == NULL) return 0;
	uint8_t i = 0;
	uint8_t* p = (uint8_t*)&data;
	for(i = 0; i < 8; ++i) {
		*(buffer + i) = *p++;
	}
	return 8;
}

bytes -> double

uint8_t bytes2double(uint8_t* buffer, double* data)
{
	if(buffer == NULL) return 0;
	*data = *((double *)buffer);
	return 8;
}