//------------------------------------------------------------------------------
//
//------------------------------------------------------------------------------
int
mbus_serial_recv_frame(mbus_handle *handle, mbus_frame *frame)
{
char buff[PACKET_BUFF_SIZE];
int remaining, timeouts;
ssize_t len, nread;
if (handle == NULL || frame == NULL)
{
fprintf(stderr, "%s: Invalid parameter.\n", __PRETTY_FUNCTION__);
return MBUS_RECV_RESULT_ERROR;
}
// Make sure serial connection is open
if (isatty(handle->fd) == 0)
{
fprintf(stderr, "%s: Serial connection is not available.\n", __PRETTY_FUNCTION__);
return MBUS_RECV_RESULT_ERROR;
}
memset((void *)buff, 0, sizeof(buff));
//
// read data until a packet is received
//
remaining = 1; // start by reading 1 byte
len = 0;
timeouts = 0;
do {
if (len + remaining > PACKET_BUFF_SIZE)
{
// avoid out of bounds access
return MBUS_RECV_RESULT_ERROR;
}
//printf("%s: Attempt to read %d bytes [len = %d]\n", __PRETTY_FUNCTION__, remaining, len);
if ((nread = read(handle->fd, &buff[len], remaining)) == -1)
{
// fprintf(stderr, "%s: aborting recv frame (remaining = %d, len = %d, nread = %d)\n",
// __PRETTY_FUNCTION__, remaining, len, nread);
return MBUS_RECV_RESULT_ERROR;
}
// printf("%s: Got %d byte [remaining %d, len %d]\n", __PRETTY_FUNCTION__, nread, remaining, len);
if (nread == 0)
{
timeouts++;
if (timeouts >= 3)
{
// abort to avoid endless loop
fprintf(stderr, "%s: Timeout\n", __PRETTY_FUNCTION__);
break;
}
}
if (len > (SSIZE_MAX-nread))
{
// avoid overflow
return MBUS_RECV_RESULT_ERROR;
}
len += nread;
} while ((remaining = mbus_parse(frame, buff, len)) > 0);
if (len == 0)
{
// No data received
return MBUS_RECV_RESULT_TIMEOUT;
}
//
// call the receive event function, if the callback function is registered
//
if (_mbus_recv_event)
_mbus_recv_event(MBUS_HANDLE_TYPE_SERIAL, buff, len);
if (remaining != 0)
{
// Would be OK when e.g. scanning the bus, otherwise it is a failure.
// printf("%s: M-Bus layer failed to receive complete data.\n", __PRETTY_FUNCTION__);
return MBUS_RECV_RESULT_INVALID;
}
if (len == -1)
{
fprintf(stderr, "%s: M-Bus layer failed to parse data.\n", __PRETTY_FUNCTION__);
return MBUS_RECV_RESULT_ERROR;
}
return MBUS_RECV_RESULT_OK;
}
//------------------------------------------------------------------------------
//
//------------------------------------------------------------------------------
int
mbus_serial_recv_frame(SoftwareSerial *handle, mbus_frame *frame)
{
uint8_t buff[PACKET_BUFF_SIZE];
int len, remaining, nread, timeouts;
printf_P(PSTR("%s: Entered \n"), __PRETTY_FUNCTION__);
if (handle == NULL || frame == NULL)
{
printf_P(PSTR("%s: Invalid parameter.\n"), __PRETTY_FUNCTION__);
return -1;
}
memset(buff, 0, sizeof(buff));
//
// read data until a packet is received
//
remaining = 1; // start by reading 1 byte
len = 0;
timeouts = 0;
printf_P(PSTR("%s: Entered3 \n"), __PRETTY_FUNCTION__);
do {
printf_P(PSTR("%s: Attempt to read %d bytes [len = %d]\n"), __PRETTY_FUNCTION__, remaining, len);
while(handle->available()>0 && len<PACKET_BUFF_SIZE)
{
buff[len] = handle->read();
len++;
}
} while ((remaining = mbus_parse(frame, buff, len)) > 0);
if (len == 0)
{
// No data received
return -1;
}
//
// call the receive event function, if the callback function is registered
//
if (_mbus_recv_event)
_mbus_recv_event(MBUS_HANDLE_TYPE_SERIAL, buff, len);
if (remaining != 0)
{
// Would be OK when e.g. scanning the bus, otherwise it is a failure.
printf_P(PSTR("%s: M-Bus layer failed to receive complete data.\n"), __PRETTY_FUNCTION__);
return -2;
}
if (len == -1)
{
printf_P(PSTR("%s: M-Bus layer failed to parse data.\n"), __PRETTY_FUNCTION__);
return -1;
}
return 0;
}