clk_meinberg.c

网络时间协议NTP 源码 版本v4.2.0b 该源码用于linux平台下

		 */
		if (f[3] == 'A')
			clock_time->flags |= PARSEB_LEAPADD;
		
		if (f[3] == 'a')
			clock_time->flags |= PARSEB_LEAPDEL;
		
		
		if (format->flags & MBG_EXTENDED)
		{
			clock_time->flags |= PARSEB_S_ANTENNA;
			
			/*
			 * DCF77 does not encode the direction -
			 * so we take the current default -
			 * earth slowing down
			 */
			clock_time->flags &= ~PARSEB_LEAPDEL;
			
			if (f[4] == 'A')
				clock_time->flags |= PARSEB_LEAPADD;
			
			if (f[5] == 'R')
				clock_time->flags |= PARSEB_ALTERNATE;
		}
		return CVT_OK;
	}
}


/*
 * mbg_input
 *
 * grep data from input stream
 */
static u_long
mbg_input(
	  parse_t      *parseio,
	  unsigned int  ch,
	  timestamp_t  *tstamp
	  )
{
	unsigned int rtc;
	
	parseprintf(DD_PARSE, ("mbg_input(0x%lx, 0x%x, ...)\n", (long)parseio, ch));
	
	switch (ch)
	{
	case STX:
		parseprintf(DD_PARSE, ("mbg_input: STX seen\n"));
		
		parseio->parse_index = 1;
		parseio->parse_data[0] = ch;
		parseio->parse_dtime.parse_stime = *tstamp; /* collect timestamp */
		return PARSE_INP_SKIP;
	  
	case ETX:
		parseprintf(DD_PARSE, ("mbg_input: ETX seen\n"));
		if ((rtc = parse_addchar(parseio, ch)) == PARSE_INP_SKIP)
			return parse_end(parseio);
		else
			return rtc;

	default:
		return parse_addchar(parseio, ch);
	}
}


/*
 * cvt_mgps
 *
 * convert Meinberg GPS format
 */
static u_long
cvt_mgps(
	 unsigned char *buffer,
	 int            size,
	 struct format *format,
	 clocktime_t   *clock_time,
	 void          *local
	)
{
	if (!Strok(buffer, format->fixed_string))
	{
		return cvt_meinberg(buffer, size, format, clock_time, local);
	}
	else
	{
		if (Stoi(&buffer[format->field_offsets[O_DAY].offset], &clock_time->day,
			 format->field_offsets[O_DAY].length) ||
		    Stoi(&buffer[format->field_offsets[O_MONTH].offset], &clock_time->month,
			 format->field_offsets[O_MONTH].length) ||
		    Stoi(&buffer[format->field_offsets[O_YEAR].offset], &clock_time->year,
			 format->field_offsets[O_YEAR].length) ||
		    Stoi(&buffer[format->field_offsets[O_HOUR].offset], &clock_time->hour,
			 format->field_offsets[O_HOUR].length) ||
		    Stoi(&buffer[format->field_offsets[O_MIN].offset], &clock_time->minute,
			 format->field_offsets[O_MIN].length) ||
		    Stoi(&buffer[format->field_offsets[O_SEC].offset], &clock_time->second,
			 format->field_offsets[O_SEC].length))
		{
			return CVT_FAIL|CVT_BADFMT;
		}
		else
		{
			long h;
			unsigned char *f = &buffer[format->field_offsets[O_FLAGS].offset];
	  
			clock_time->flags = PARSEB_S_LEAP|PARSEB_S_POSITION;
	      
			clock_time->usecond = 0;

			/*
			 * calculate UTC offset
			 */
			if (Stoi(&buffer[format->field_offsets[O_UTCHOFFSET].offset], &h,
				 format->field_offsets[O_UTCHOFFSET].length))
			{
				return CVT_FAIL|CVT_BADFMT;
			}
			else
			{
				if (Stoi(&buffer[format->field_offsets[O_UTCMOFFSET].offset], &clock_time->utcoffset,
					 format->field_offsets[O_UTCMOFFSET].length))
				{
					return CVT_FAIL|CVT_BADFMT;
				}

				clock_time->utcoffset += TIMES60(h);
				clock_time->utcoffset  = TIMES60(clock_time->utcoffset);

				if (buffer[format->field_offsets[O_UTCSOFFSET].offset] != '-')
				{
					clock_time->utcoffset = -clock_time->utcoffset;
				}
			}
	  
			/*
			 * gather status flags
			 */
			if (buffer[format->field_offsets[O_ZONE].offset] == 'S')
			    clock_time->flags    |= PARSEB_DST;
	  
			if (clock_time->utcoffset == 0)
			    clock_time->flags |= PARSEB_UTC;
	  
			/*
			 * no sv's seen - no time & position
			 */
			if (f[0] == '#')
			    clock_time->flags |= PARSEB_POWERUP;
	  
			/*
			 * at least one sv seen - time (for last position)
			 */
			if (f[1] == '*')
			    clock_time->flags |= PARSEB_NOSYNC;
			else
			    if (!(clock_time->flags & PARSEB_POWERUP))
				clock_time->flags |= PARSEB_POSITION;
	  
			/*
			 * oncoming zone switch
			 */
			if (f[3] == '!')
			    clock_time->flags |= PARSEB_ANNOUNCE;
	  
			/*
			 * oncoming leap second
			 * 'a' code not confirmed - earth is not
			 * expected to speed up
			 */
			if (f[4] == 'A')
			    clock_time->flags |= PARSEB_LEAPADD;
	  
			if (f[4] == 'a')
			    clock_time->flags |= PARSEB_LEAPDEL;

			/*
			 * f[5] == ' '
			 */
	  
			/*
			 * this is the leap second
			 */
			if ((f[6] == 'L') || (clock_time->second == 60))
			    clock_time->flags |= PARSEB_LEAPSECOND;

			return CVT_OK;
		}
	}
}

/*
 * gps_input
 *
 * grep binary data from input stream
 */
static u_long
gps_input(
	  parse_t      *parseio,
	  unsigned int  ch,
	  timestamp_t  *tstamp
	  )
{
  CSUM calc_csum;                    /* used to compare the incoming csums */
  GPS_MSG_HDR header;
  struct msg_buf *msg_buf;
  
  msg_buf = (struct msg_buf *)parseio->parse_pdata;

  parseprintf(DD_PARSE, ("gps_input(0x%lx, 0x%x, ...)\n", (long)parseio, ch));

  if (!msg_buf)
    return PARSE_INP_SKIP;
  
  if ( msg_buf->phase == MBG_NONE )
    {                  /* not receiving yet */
      switch (ch)
	{
	case SOH:
	  parseprintf(DD_PARSE, ("gps_input: SOH seen\n"));
	  
	  msg_buf->len = sizeof( header ); /* prepare to receive msg header */
	  msg_buf->phase = MBG_HEADER; /* receiving header */
	  break;

	case STX:
	  parseprintf(DD_PARSE, ("gps_input: STX seen\n"));

	  msg_buf->len = 0;
	  msg_buf->phase = MBG_STRING; /* prepare to receive ASCII ETX delimited message */
	  parseio->parse_index = 1;
	  parseio->parse_data[0] = ch;
	  break;
	  
	default:
	  return PARSE_INP_SKIP;	/* keep searching */
	}

      parseio->parse_dtime.parse_msglen = 1; /* reset buffer pointer */
      parseio->parse_dtime.parse_msg[0] = ch; /* fill in first character */
      parseio->parse_dtime.parse_stime  = *tstamp; /* collect timestamp */
      return PARSE_INP_SKIP;
    }

  /* SOH/STX has already been received */

  /* save incoming character in both buffers if needbe */
  if ((msg_buf->phase == MBG_STRING) &&
      (parseio->parse_index < parseio->parse_dsize))
    parseio->parse_data[parseio->parse_index++] = ch;
  
  parseio->parse_dtime.parse_msg[parseio->parse_dtime.parse_msglen++] = ch;

  if (parseio->parse_dtime.parse_msglen > sizeof(parseio->parse_dtime.parse_msg))
    {
      msg_buf->phase = MBG_NONE; /* buffer overflow - discard */
      parseio->parse_data[parseio->parse_index] = '\0';
      memcpy(parseio->parse_ldata, parseio->parse_data, (unsigned)(parseio->parse_index+1));
      parseio->parse_ldsize = parseio->parse_index+1;
      return PARSE_INP_DATA;
    }
  
  switch (msg_buf->phase)
    {
    case MBG_HEADER:
    case MBG_DATA:
      msg_buf->len--;

      if ( msg_buf->len )               /* transfer not complete */
	return PARSE_INP_SKIP;

      parseprintf(DD_PARSE, ("gps_input: %s complete\n", (msg_buf->phase == MBG_DATA) ? "data" : "header"));

      break;

    case MBG_STRING:
      if ((ch == ETX) || (parseio->parse_index >= parseio->parse_dsize))
	{
	  msg_buf->phase = MBG_NONE;
	  parseprintf(DD_PARSE, ("gps_input: string complete\n"));
	  parseio->parse_data[parseio->parse_index] = '\0';
	  memcpy(parseio->parse_ldata, parseio->parse_data, (unsigned)(parseio->parse_index+1));
	  parseio->parse_ldsize = parseio->parse_index+1;
	  parseio->parse_index = 0;
	  return PARSE_INP_TIME;
	}
      else
	{
	  return PARSE_INP_SKIP;
	}
    }

  /* cnt == 0, so the header or the whole message is complete */

  if ( msg_buf->phase == MBG_HEADER )
    {         /* header complete now */
      unsigned char *datap = parseio->parse_dtime.parse_msg + 1;
      
      get_mbg_header(&datap, &header);
      
      parseprintf(DD_PARSE, ("gps_input: header: cmd 0x%x, len %d, dcsum 0x%x, hcsum 0x%x\n",
			     (int)header.gps_cmd, (int)header.gps_len, (int)header.gps_data_csum,
			     (int)header.gps_hdr_csum));
      

      calc_csum = mbg_csum( (unsigned char *) parseio->parse_dtime.parse_msg + 1, (unsigned short)6 );

      if ( calc_csum != header.gps_hdr_csum )
	{
	  parseprintf(DD_PARSE, ("gps_input: header checksum mismatch expected 0x%x, got 0x%x\n",
				 (int)calc_csum, (int)mbg_csum( (unsigned char *) parseio->parse_dtime.parse_msg, (unsigned short)6 )));
	  
	  msg_buf->phase = MBG_NONE;  /* back to hunting mode */
	  return PARSE_INP_DATA;      /* invalid header checksum received - pass up for detection */
	}

      if ((header.gps_len == 0)  ||       /* no data to wait for */
	  (header.gps_len >= (sizeof (parseio->parse_dtime.parse_msg) - sizeof(header) - 1)))	/* blows anything we have space for */
	{
	  msg_buf->phase = MBG_NONE;  /* back to hunting mode */
	  return (header.gps_len == 0) ? PARSE_INP_DATA : PARSE_INP_SKIP; /* message complete/throwaway */
	}
    
      parseprintf(DD_PARSE, ("gps_input: expecting %d bytes of data message\n", (int)header.gps_len));
      
      msg_buf->len   = header.gps_len;/* save number of bytes to wait for */
      msg_buf->phase = MBG_DATA;      /* flag header already complete */
      return PARSE_INP_SKIP;
    }

  parseprintf(DD_PARSE, ("gps_input: message data complete\n"));
  
  /* Header and data have been received. The header checksum has been */
  /* checked */

  msg_buf->phase = MBG_NONE;	      /* back to hunting mode */
  return PARSE_INP_DATA;              /* message complete, must be evaluated */
}

#else /* not (REFCLOCK && CLOCK_PARSE && CLOCK_MEINBERG) */
int clk_meinberg_bs;
#endif /* not (REFCLOCK && CLOCK_PARSE && CLOCK_MEINBERG) */

/*
 * History:
 *
 * clk_meinberg.c,v
 * Revision 4.12  2005/04/16 17:32:10  kardel
 * update copyright
 *
 * Revision 4.11  2004/11/14 15:29:41  kardel
 * support PPSAPI, upgrade Copyright to Berkeley style
 *
 * Revision 4.8  1999/11/28 09:13:50  kardel
 * RECON_4_0_98F
 *
 * Revision 4.7  1999/02/21 11:09:14  kardel
 * cleanup
 *
 * Revision 4.6  1998/06/14 21:09:36  kardel
 * Sun acc cleanup
 *
 * Revision 4.5  1998/06/13 15:18:54  kardel
 * fix mem*() to b*() function macro emulation
 *
 * Revision 4.4  1998/06/13 12:03:23  kardel
 * fix SYSV clock name clash
 *
 * Revision 4.3  1998/06/12 15:22:28  kardel
 * fix prototypes
 *
 * Revision 4.2  1998/05/24 16:14:42  kardel
 * support current Meinberg standard data formats
 *
 * Revision 4.1  1998/05/24 09:39:52  kardel
 * implementation of the new IO handling model
 *
 * Revision 4.0  1998/04/10 19:45:29  kardel
 * Start 4.0 release version numbering
 *
 * from V3 3.23 - log info deleted 1998/04/11 kardel
 *
 */